1,588 results on '"Hamdan A."'
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2. Influence of aluminum addition on the mechanical properties of brass/Al composites fabricated by stir casting
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Hamdan H. Ya, Mohammad Azeem, Faisal Masood, Akhlaq Ahmad, Mohammad Yusuf, and Mohammad Azad Alam
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010302 applied physics ,Materials science ,Composite number ,chemistry.chemical_element ,02 engineering and technology ,021001 nanoscience & nanotechnology ,01 natural sciences ,law.invention ,Brass ,Thermal conductivity ,Optical microscope ,chemistry ,law ,Aluminium ,Casting (metalworking) ,visual_art ,0103 physical sciences ,Advanced composite materials ,Ultimate tensile strength ,visual_art.visual_art_medium ,Composite material ,0210 nano-technology - Abstract
Brass has an interesting set of characteristics, such as good wear capabilities and high electrical and thermal conductivity. Aluminium has been utilized as reinforcement and matrix in the development of advanced composites. In the present investigation, the new unique material the brass/Al composite has been developed by liquid casting route. The effect of Al filler in varying wt.% on the mechanical properties of new brass/Al composites were investigated. The tensile strength and hardness were evaluated for produced composites. The microstructural features were observed by optical microscopy. The optical microscopy revealed the uniform distribution of Al particles in the brass matrix. The tensile strength and hardness increased by increasing the Al contents. It was interestingly observed that the addition of 4 wt% Al exhibits the uniform distribution of irregular block shape strengthening phase and has the best mechanical properties. The fine surface was obtained by addition of Al. This research work provides an advanced strategy for improving the overall characteristics of existing brass.
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- 2022
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3. De novo DHDDS variants cause a neurodevelopmental and neurodegenerative disorder with myoclonus
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Daniëlle G. M. Bosch, Nicole Corsten-Janssen, Colin A Ellis, Dirk Lefeber, Alfredo Brusco, Irene Bagnasco, Andrea Accogli, Ellen Macnamara, Carlo Di Bonaventura, Giovanna Zorzi, Scott Demarest, Erik A. Eklund, Noëlle Mercier, Carlo Marcelis, Rong Zhang, Ban H Edani, Camilo Toro, Ziv Gan-Or, Simone Pizzi, Kariona A. Grabińska, Nienke E. Verbeek, Karen W. Gripp, Simone Martinelli, Caterina Caputi, Luca Pannone, Marco Tartaglia, Felix Distelmaier, Louise Amlie-Wolf, Luisa Averdunk, Anne-Sophie Alaix, Renzo Guerrini, Laura Masuelli, Marwan Shinawi, Sunita Venkateswaran, Joseph Peeden, Hana Hansikova, Lucie Zdrazilova, William C. Sessa, Serena Galosi, Renske Oegema, Patricia G Wheeler, Kristin W. Barañano, Vincenzo Leuzzi, Frances Elmslie, Fadi F. Hamdan, Roberto Bei, Jean-Marc Good, Isis Atallah, Myriam Srour, and Erik-Jan Kamsteeg
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Myoclonus ,Ataxia ,Retinitis ,Progressive myoclonus epilepsy ,congenital disorders of glycosylation ,dolichol ,movement disorder ,myoclonus epilepsy ,neurodegenerative disorder ,DHDDS ,Biology ,Settore MED/04 ,Sensory disorders Donders Center for Medical Neuroscience [Radboudumc 12] ,chemistry.chemical_compound ,Neurodevelopmental disorder ,Dolichol ,Dolichols ,Retinitis pigmentosa ,medicine ,Alkyl and Aryl Transferases ,Child ,Dolichols/metabolism ,Humans ,Neurodegenerative Diseases/genetics ,Retinitis Pigmentosa/genetics ,PROTEIN GLYCOSYLATION ,MUTATION ,NOGO-B RECEPTOR ,CIS-PRENYLTRANSFERASE ,Genetics ,Neurodevelopmental disorders Donders Center for Medical Neuroscience [Radboudumc 7] ,Neurodegenerative Diseases ,LOCALIZATION ,medicine.disease ,Disorders of movement Donders Center for Medical Neuroscience [Radboudumc 3] ,OLIGOSACCHARIDES ,INSIGHTS ,chemistry ,Neuronal ceroid lipofuscinosis ,Original Article ,Neurology (clinical) ,medicine.symptom ,LIQUID-CHROMATOGRAPHY ,Retinitis Pigmentosa ,GENETIC-DEFECTS - Abstract
Subcellular membrane systems are highly enriched in dolichol, whose role in organelle homeostasis and endosomal-lysosomal pathway remains largely unclear besides being involved in protein glycosylation. DHDDS encodes for the catalytic subunit (DHDDS) of the enzyme cis-prenyltransferase (cis-PTase), involved in dolichol biosynthesis and dolichol-dependent protein glycosylation in the endoplasmic reticulum. An autosomal recessive form of retinitis pigmentosa (retinitis pigmentosa 59) has been associated with a recurrent DHDDS variant. Moreover, two recurring de novo substitutions were detected in a few cases presenting with neurodevelopmental disorder, epilepsy and movement disorder. We evaluated a large cohort of patients (n = 25) with de novo pathogenic variants in DHDDS and provided the first systematic description of the clinical features and long-term outcome of this new neurodevelopmental and neurodegenerative disorder. The functional impact of the identified variants was explored by yeast complementation system and enzymatic assay. Patients presented during infancy or childhood with a variable association of neurodevelopmental disorder, generalized epilepsy, action myoclonus/cortical tremor and ataxia. Later in the disease course, they experienced a slow neurological decline with the emergence of hyperkinetic and/or hypokinetic movement disorder, cognitive deterioration and psychiatric disturbances. Storage of lipidic material and altered lysosomes were detected in myelinated fibres and fibroblasts, suggesting a dysfunction of the lysosomal enzymatic scavenger machinery. Serum glycoprotein hypoglycosylation was not detected and, in contrast to retinitis pigmentosa and other congenital disorders of glycosylation involving dolichol metabolism, the urinary dolichol D18/D19 ratio was normal. Mapping the disease-causing variants into the protein structure revealed that most of them clustered around the active site of the DHDDS subunit. Functional studies using yeast complementation assay and in vitro activity measurements confirmed that these changes affected the catalytic activity of the cis-PTase and showed growth defect in yeast complementation system as compared with the wild-type enzyme and retinitis pigmentosa-associated protein. In conclusion, we characterized a distinctive neurodegenerative disorder due to de novo DHDDS variants, which clinically belongs to the spectrum of genetic progressive encephalopathies with myoclonus. Clinical and biochemical data from this cohort depicted a condition at the intersection of congenital disorders of glycosylation and inherited storage diseases with several features akin to of progressive myoclonus epilepsy such as neuronal ceroid lipofuscinosis and other lysosomal disorders.
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- 2022
4. The effects of combining erbium, chromium: Yttrium-scandium-gallium-garnet laser irradiation with fluoride application in controlling the progression of enamel erosion
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Rahaf bin Hamdan, Malak AlDaweesh, Ahoud Alshamrani, Alhanouf Alhabdan, and Randa AlRajhi
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Materials science ,Enamel microhardness ,chemistry.chemical_element ,Indentation hardness ,law.invention ,030207 dermatology & venereal diseases ,03 medical and health sciences ,Chromium ,chemistry.chemical_compound ,Acidulated Phosphate Fluoride ,0302 clinical medicine ,Chromium: yttrium-scandium-gallium-garnet laser ,stomatognathic system ,law ,Irradiation ,Fluoride ,General Dentistry ,Enamel paint ,RK1-715 ,030206 dentistry ,Laser ,stomatognathic diseases ,chemistry ,Enamel ,Dentistry ,visual_art ,visual_art.visual_art_medium ,Medicine ,Original Article ,Dental erosion ,Citric acid ,Erbium ,Nuclear chemistry - Abstract
Highlights • Fluoride alone increased the microhardness of the enamel surface. • Fluoride alone halted the progression of enamel erosion. • Laser irradiation before fluoride-induced similar effects as fluoride alone. • Laser irradiation alone did not prevent the progression of enamel erosion., Objective Increasing enamel resistance to acid may be useful for preventing cavitation and could reduce changes in the enamel’s microhardness. Topical fluoride application and laser irradiation promote acid resistance of dental substrates. The aim of the study was to assess the efficacy of erbium, chromium: yttrium-scandium-gallium-garnet laser irradiation in combination with fluoride application to control enamel erosion. Design Sixty human premolar specimens were prepared (N = 60) and were randomly assigned to 5 groups, twelve specimens in each group (n = 12/group) according to surface treatment. The groups were as follows: group 1 (C): control with no treatment; group 2 (F): application of 1.23% acidulated phosphate fluoride gel alone; group 3 (L): laser irradiation alone; group 4 (F+L): acidulated phosphate fluoride gel followed by laser irradiation; group 5 (L+F): laser irradiation followed by acidulated phosphate fluoride gel. All the specimens were eroded 10 min in citric acid. Baseline measurements were performed using a Vickers microhardness tester before surface treatment. Subsequently, all specimens were subjected to a 60 min erosion-remineralization cycle for five days followed by measurements of the final surface microhardness. Statistical comparisons were performed by a one-way analysis of variance and Tukey’s post hoc analysis. Results The control, laser, and fluoride + laser groups showed a statistically significant decrease in microhardness values between baseline and post-erosion measurements (P
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- 2021
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5. Effect of sulfur content in the crude oil to the corrosion behavior of internal surface of API 5L X65 petroleum pipeline steel
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Mohd Asyadi Azam, Nur Ezyanie Safie, and Hazwan Hasif Hamdan
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chemistry.chemical_compound ,Materials science ,Petroleum engineering ,chemistry ,Pipeline (computing) ,Sulfur content ,Petroleum ,Crude oil ,Corrosion behavior ,Industrial and Manufacturing Engineering - Published
- 2021
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6. The impact of early target attainment of vancomycin in critically ill patients with confirmed Gram-positive infection: A retrospective cohort study
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Shmeylan Al Harbi, Ramesh Vishwakarma, Ohoud Aljuhani, Nawaf Alghamdi, Abdulrahman Alshaya, Khalid Al Sulaiman, Nadiyah Alshehri, Sara Althewaibi, Khalid Alhelal, Amjad Alsaeed, Aisha Alharbi, and Hamdan Alzahrani
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Adult ,medicine.medical_specialty ,Critical Illness ,Population ,Infectious and parasitic diseases ,RC109-216 ,law.invention ,chemistry.chemical_compound ,Medical microbiology ,law ,Vancomycin ,Internal medicine ,medicine ,Humans ,Intensive care unit ,Mortality ,education ,Retrospective Studies ,education.field_of_study ,Creatinine ,Trough level ,business.industry ,Research ,Acute kidney injury ,Retrospective cohort study ,Acute Kidney Injury ,medicine.disease ,Anti-Bacterial Agents ,Critical care ,Infectious Diseases ,chemistry ,business ,Infection ,medicine.drug - Abstract
Background Vancomycin is a commonly used antibiotic in critically ill patients for various indications. Critical illness imposes pharmacokinetic-pharmacodynamics challenges, which makes optimizing vancomycin in this population cumbersome. Data are scarce on the clinical impact of time to therapeutic trough levels of vancomycin in critically ill patients. This study aims to evaluate the timing to achieve therapeutic trough level of vancomycin on 30-day mortality in critically ill patients. Method A retrospective cohort study was conducted for all adult critically ill patients with confirmed Gram-positive infection who received IV vancomycin between January 1, 2017, and December 31, 2020. We compared early ( Results A total of 326 patients were included; 110 patients attained the therapeutic trough levels within 48 h of vancomycin initiation. Late achievement of the therapeutic trough levels was associated with higher 30-day mortality (HR: 2.54; 95% CI [1.24–5.22]; p = 0.01). Additionally, patients who achieved therapeutic trough levels of vancomycin late were more likely to develop AKI (OR = 2.59; 95% CI [1.01–6.65]; p = 0.04). Other outcomes were not statistically significant between the two groups. Conclusion Early achievement of vancomycin therapeutic levels in patients with confirmed Gram-positive infection was associated with possible survival benefits.
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- 2021
7. Adsorption of Lead Ions from Aqueous Solutions onto Rice Husks, Continuous System
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Nagam Obaid Kariem, Laith Hamdan Hawal, and Ali Omran Al-Sulttani
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lead ,Aqueous solution ,Chemistry ,ph ,Inorganic chemistry ,rice husks ,Husk ,Environmental technology. Sanitary engineering ,Ion ,Environmental sciences ,Adsorption ,Lead (geology) ,adsorption ,removal capacity ,GE1-350 ,Ecology, Evolution, Behavior and Systematics ,TD1-1066 ,General Environmental Science - Abstract
The continuous system of lead adsorption on rice husks was investigated in this paper. Fixed bed study was performed in many tests to investigate the influence of pH, the adsorbent height, the initial concentration of lead, the flow rate and processing time on the lead adsorption process. The results demonstrated that the lead removal capacity decreased when the pH value of the solution and the flow rate increased. The lead removal capacity increased due to the decreased initial concentration of lead. The results showed that the removal capacity increases with the increase in processing time and the adsorbent height in column. The largest removal was (81%) at pH of 4,the adsorbent height (50 cm), the initial concentration of lead (10 mg/l), the processing time (90 min.) and the flow rate (10 ml/min.). As a result, rice husks can be used to remove the lead instead of expensive commercial adsorbents, due to its availability, inexpensive and perfect adsorption property.
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- 2021
8. Influenza clinical testing and oseltamivir treatment in hospitalized children with acute respiratory illness, 2015–2016
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Monica N Singer, Leila C. Sahni, Angela P Campbell, Christopher J. Harrison, Flor M. Munoz, Julie A. Boom, Parvin H. Azimi, Janet A. Englund, Rangaraj Selvarangan, Monica M. McNeal, Herdi Rahman, Peter G. Szilagyi, Lubna Hamdan, Mary A. Staat, Natasha B. Halasa, Andrew J. Spieker, Laura S Stewart, Geoffrey A. Weinberg, Simon N. Vandekar, John V. Williams, Zaid Haddadin, Manish M. Patel, Eileen J. Klein, and Varvara Probst
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Lung Diseases ,Pulmonary and Respiratory Medicine ,Oseltamivir ,medicine.medical_specialty ,Neuromuscular disease ,Epidemiology ,Influenza season ,Health outcomes ,Antiviral Agents ,Risk profile ,chemistry.chemical_compound ,Internal medicine ,Influenza, Human ,medicine ,Humans ,Antiviral treatment ,Child ,Respiratory illness ,business.industry ,Public Health, Environmental and Occupational Health ,medicine.disease ,Hospitalization ,Infectious Diseases ,chemistry ,Lung disease ,business ,Child, Hospitalized - Abstract
Antiviral treatment is recommended for all hospitalized children with suspected or confirmed influenza, regardless of their risk profile. Few data exist on adherence to these recommendations, so we sought to determine factors associated with influenza testing and antiviral treatment in children.Hospitalized children18 years of age with acute respiratory illness (ARI) were enrolled through active surveillance at pediatric medical centers in seven cities between 11/1/2015 and 6/30/2016; clinical information was obtained from parent interview and chart review. We used generalized linear mixed-effects models to identify factors associated with influenza testing and antiviral treatment.Of the 2299 hospitalized children with ARI enrolled during one influenza season, 51% (n = 1183) were tested clinically for influenza. Clinicians provided antiviral treatment for 61 of 117 (52%) patients with a positive influenza test versus 66 of 1066 (6%) with a negative or unknown test result. In multivariable analyses, factors associated with testing included neuromuscular disease (aOR = 5.35, 95% CI [3.58-8.01]), immunocompromised status (aOR = 2.88, 95% CI [1.66-5.01]), age (aOR = 0.93, 95% CI [0.91-0.96]), private only versus public only insurance (aOR = 0.78, 95% CI [0.63-0.98]), and chronic lung disease (aOR = 0.64, 95% CI [0.51-0.81]). Factors associated with antiviral treatment included neuromuscular disease (aOR = 1.86, 95% CI [1.04, 3.31]), immunocompromised state (aOR = 2.63, 95% CI [1.38, 4.99]), duration of illness (aOR = 0.92, 95% CI [0.84, 0.99]), and chronic lung disease (aOR = 0.60, 95% CI [0.38, 0.95]).Approximately half of children hospitalized with influenza during the 2015-2016 influenza season were treated with antivirals. Because antiviral treatment for influenza is associated with better health outcomes, further studies of subsequent seasons would help evaluate current use of antivirals among children and better understand barriers for treatment.
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- 2021
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9. Cryo-EM structure of human Pol κ bound to DNA and mono-ubiquitylated PCNA
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Vlad-Stefan Raducanu, Alfredo De Biasio, Souvika Bakshi, Ramon Crehuet, Masateru Takahashi, Matthew Percival, Samir M. Hamdan, Timothy J. Ragan, Frederick W. Muskett, Mohamed Abdelmaboud Sobhy, Muhammad Tehseen, Claudia Lancey, Kerry Blair, and Ministerio de Economía y Competitividad (España)
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Ubiquitin binding ,DNA polymerase ,DNA damage ,viruses ,Science ,General Physics and Astronomy ,DNA-Directed DNA Polymerase ,Protomer ,Article ,General Biochemistry, Genetics and Molecular Biology ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Ubiquitin ,Cryoelectron microscopy ,Proliferating Cell Nuclear Antigen ,Humans ,Polymerase ,030304 developmental biology ,0303 health sciences ,Multidisciplinary ,biology ,Ubiquitination ,General Chemistry ,DNA ,Proliferating cell nuclear antigen ,chemistry ,biology.protein ,Biophysics ,030217 neurology & neurosurgery ,DNA Damage ,Protein Binding - Abstract
Y-family DNA polymerase κ (Pol κ) can replicate damaged DNA templates to rescue stalled replication forks. Access of Pol κ to DNA damage sites is facilitated by its interaction with the processivity clamp PCNA and is regulated by PCNA mono-ubiquitylation. Here, we present cryo-EM reconstructions of human Pol κ bound to DNA, an incoming nucleotide, and wild type or mono-ubiquitylated PCNA (Ub-PCNA). In both reconstructions, the internal PIP-box adjacent to the Pol κ Polymerase-Associated Domain (PAD) docks the catalytic core to one PCNA protomer in an angled orientation, bending the DNA exiting the Pol κ active site through PCNA, while Pol κ C-terminal domain containing two Ubiquitin Binding Zinc Fingers (UBZs) is invisible, in agreement with disorder predictions. The ubiquitin moieties are partly flexible and extend radially away from PCNA, with the ubiquitin at the Pol κ-bound protomer appearing more rigid. Activity assays suggest that, when the internal PIP-box interaction is lost, Pol κ is retained on DNA by a secondary interaction between the UBZs and the ubiquitins flexibly conjugated to PCNA. Our data provide a structural basis for the recruitment of a Y-family TLS polymerase to sites of DNA damage., This research was supported by King Abdullah University of Science and Technology through core funding (to S.M.H.) and the Competitive Research Award Grant CRG8 URF/1/4036‐01‐01 (to S.M.H. and A.D.B.), and by the Wellcome Trust (to A.D.B.). R.C. acknowledges funding from the MINECO (CTQ2016-78636-P) and to AGAUR, (2017 SGR 324). The MD project has been carried out using CSUC resources. We acknowledge The Midlands Regional Cryo-EM Facility at the Leicester Institute of Structural and Chemical Biology (LISCB), major funding from MRC (MC_PC_17136). We thank Christos Savva (LISCB, University of Leicester) for his help in cryo-EM data collection and advice on data processing.
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- 2021
10. Integrated ultrasound-mechanical stirrer technique for extraction of total alkaloid content from Annona muricata
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Norfadilah Hamdan, Nurul Alia Azmi, Pei Ying Ong, Syieluing Wong, Ting Hun Lee, Chia Hau Lee, and Amal A.M. Elgharbawy
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Chromatography ,biology ,Central composite design ,Chemistry ,DPPH ,Alkaloid ,Extraction (chemistry) ,Bioengineering ,biology.organism_classification ,Applied Microbiology and Biotechnology ,Biochemistry ,Solvent ,chemistry.chemical_compound ,Yield (chemistry) ,Response surface methodology ,Annona muricata - Abstract
Ultrasound-mechanical stirrer assisted extraction (UMSAE) of extraction yield, total alkaloid content (TAC) and antioxidant (DPPH) activity from Annona muricata leaves were optimized using response surface methodology. Five factors were screened using Plackett-Burman Design to investigate the variables that significantly influence the extraction yield, TAC and DPPH activity, namely solvent concentration, extraction time, ultrasound power, plant material to solvent ratio, and extraction temperature. According to statistical significance analysis, solvent concentration, ultrasound power, plant material to solvent ratio, and extraction temperature were selected for further optimization of the UMSAE extraction process using a Central Composite Design. ANOVA results exhibited that the obtained models were significant at 95 % confidence level. Satisfactory extraction yields (26.38 %) and TAC (39.73 mg AE/g) were obtained with relatively short extraction time under the optimum conditions compared with conventional Soxhlet extraction. The extract prepared under UMSAE displayed excellent DPPH activity (93.15 %). The optimized UMSAE promoted considerable yield increases 1.59-fold the yield extract, 2.32-fold TAC, and 1.19-fold antioxidant activity if compared to the Soxhlet extraction. This study provides the ideal integrated UMSAE settings for the maximum recovery of total alkaloid content with high antioxidant activity from A. muricata for possible utilization of their leaves in food applications.
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- 2021
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11. The Effect of Tafamidis on Circulating Endothelial Progenitor Cells in Patients with Transthyretin Cardiac Amyloidosis
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Ran Kornowski, Irit Kandinov, Ashraf Hamdan, Osnat Itzhaki Ben Zadok, Tali Steinmetz, Dorit Leshem-Lev, Ilit Ovadia, Tuvia Ben-Gal, Alon Eisen, and Nili Schamroth Pravda
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Pharmacology ,Tafamidis ,medicine.medical_specialty ,biology ,medicine.diagnostic_test ,business.industry ,Angiogenesis ,CD34 ,General Medicine ,Gastroenterology ,Flow cytometry ,Transthyretin ,chemistry.chemical_compound ,Cardiac amyloidosis ,chemistry ,Internal medicine ,Concomitant ,biology.protein ,medicine ,Pharmacology (medical) ,Progenitor cell ,Cardiology and Cardiovascular Medicine ,business - Abstract
Endothelial microvascular dysfunction is a known mechanism of vascular pathology in cardiac amyloidosis (CA). Scientific evidence regarding the possible protective role of the amyloid transthyretin (ATTR) stabilizer, tafamidis, is lacking. Circulating endothelial progenitor cells (cEPCs) have an important role in the process of vascular repair. We aimed to examine the effect of tafamidis on cEPCs. Study population included patients with ATTR-CA. cEPCs were assessed using flow cytometry by the expression of CD34(+)/CD133(+) and vascular endothelial growth factor receptor (VEGFR)-2(+) and by the formation of colony-forming units (CFUs) and production of VEGF. Tests were repeated at pre-specified time-points up to 12 months following the initiation of tafamidis. Included were 18 ATTR-CA patients at a median age of 77 (IQR 71, 85) years and male predominance (n = 15, 83%). Following the initiation of tafamidis and during 12 months of drug treatment, there was a gradual increase in the levels of CD34(+)/VEGFR-2(+) (0.43 to 2.42% (IQR 1.53, 2.91)%, p = 0.002) and CD133(+)/VEGFR-2(+) (0.49 to 1.64% (IQR 0.97, 2.90)%, p = 0.004). Functionally, increase in EPCs-CFUs was microscopically evident following treatment with tafamidis (from 0.5 CFUs (IQR 0.0, 1.0) to 3.0 (IQR 1.3, 3.8) p
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- 2021
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12. APPLYING NANOPARTICLES FOR TREATING GIARDIA INFECTION: A SYSTEMATIC REVIEW
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Ghaidaa Raheem Lateef Al-Awsi, Aishah E. Albalawi, Hadeel Al Sadoun, Hamdan I. Almohammed, Ali Moghaddam, Navid Bakhtiari, and Morteza Amraei
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biology ,Chemistry ,Pharmaceutical Science ,Nanoparticle ,Giardia ,biology.organism_classification ,Pharmacology, Toxicology and Pharmaceutics (miscellaneous) ,Microbiology - Abstract
At present, chemotherapy with some drugs such as nitroimidazoes derivatives is the preferred treatment for giardiasis. However, these agents are associated with adverse side effects ranging from nausea to possible genotoxicity. The present investigation was designed to systematically review the in vitro, in vivo, and clinical studies about the efficacy of nanoparticles against giardiasis. The study was carried out based on the 06-PRISMA guideline and registered in the CAMARADES-NC3Rs Preclinical Systematic Review and Meta-analysis Facility (SyRF) database. The search was performed in five English databases, including Scopus, PubMed, Web of Science, EMBASE, and Google Scholar, without time limitation for publications around the world about anti-Giardia effects of all organic and inorganic nanoparticles without date limitation in order to identify all the published articles. The searched words and terms were “Giardiasis”, “Giardia lamblia”, “Giardia intestinalis”, “Giardia duodenalis”, “nanoparticles”, “nanomedicine”, “in vitro”, in vivo”, and “clinical trial”. Out of 312 papers, 10 papers, including 4 in vitro (40.0%), 5 in vivo (50.0%), and 1 in vitro/in vivo (10.0%) up to 2021 met the inclusion criteria for discussion in this systematic review. The most common type of nanoparticles was metal nanoparticles (5 studies, 50.0%) such as silver, gold, etc., followed by organic nanoparticles such as chitosan nanoparticles (4 studies, 40.0%). The results of this review study showed the high efficacy of a wide range of organic and non-organic NPs against giardiasis, indicating that nanoparticles could be considered as an alternative and complementary resource for treating giardiasis, since they have no significant toxicity. However, more studies are required to elucidate this conclusion, especially in clinical systems.
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- 2021
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13. Synthesis of Silicon and Silicon Carbide Nanoparticles by Pulsed Electrical Discharges in Dielectric Liquids
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Min Suk Cha, Ahmad Hamdan, and Douaa El Abiad
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Materials science ,Silicon ,business.industry ,General Chemical Engineering ,Liquid dielectric ,Nanoparticle ,chemistry.chemical_element ,General Chemistry ,Dielectric ,Condensed Matter Physics ,Surfaces, Coatings and Films ,chemistry.chemical_compound ,chemistry ,Electrical resistance and conductance ,Electrode ,Silicon carbide ,Optoelectronics ,business ,Tetramethylsilane - Abstract
Silicon carbide (SiC) has been widely used in many applications, which require high mechanical endurance or high electrical resistance. It also serves as a basic material for light emitting diodes. Here, we present an in-liquid plasma method to produce SiC nanoparticles. A sustained spark-discharge in a dielectric liquid, which is energized by a nanosecond pulsed power supply, is established for the synthesis. To provide Si and C, we employed graphite and silicon as electrodes and cyclohexane (CHX) and tetramethylsilane (TMS) as dielectric liquids. For a reasonable comparison, we tested various combinations of electrode and liquid, namely Si-to-C in CHX, Si-to-Si in CHX, and C-to-C in TMS. We found that discharges in CHX produce Si particles encapsulated in C-shell and Si nanoparticles in C-matrix. Meanwhile, discharges in TMS consistently produce SiC nanoparticles with an average size of ~ 10 nm, regardless of the electrode material.
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- 2021
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14. Thermostable lipases and their dynamics of improved enzymatic properties
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Suriana Sabri, Mohd Shukuri Mohamad Ali, Siti Hajar Hamdan, Yahaya M. Normi, Thean Chor Leow, and Jonathan Maiangwa
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chemistry.chemical_classification ,biology ,Chemistry ,Thermophile ,General Medicine ,Protein engineering ,Applied Microbiology and Biotechnology ,Enzyme structure ,Enzyme ,Biodiesel production ,biology.protein ,Native state ,Biochemical engineering ,Lipase ,Biotechnology ,Thermostability - Abstract
Thermal stability is one of the most desirable characteristics in the search for novel lipases. The search for thermophilic microorganisms for synthesising functional enzyme biocatalysts with the ability to withstand high temperature, and capacity to maintain their native state in extreme conditions opens up new opportunities for their biotechnological applications. Thermophilic organisms are one of the most favoured organisms, whose distinctive characteristics are extremely related to their cellular constituent particularly biologically active proteins. Modifications on the enzyme structure are critical in optimizing the stability of enzyme to thermophilic conditions. Thermostable lipases are one of the most favourable enzymes used in food industries, pharmaceutical field, and actively been studied as potential biocatalyst in biodiesel production and other biotechnology application. Particularly, there is a trade-off between the use of enzymes in high concentration of organic solvents and product generation. Enhancement of the enzyme stability needs to be achieved for them to maintain their enzymatic activity regardless the environment. Various approaches on protein modification applied since decades ago conveyed a better understanding on how to improve the enzymatic properties in thermophilic bacteria. In fact, preliminary approach using advanced computational analysis is practically conducted before any modification is being performed experimentally. Apart from that, isolation of novel extremozymes from various microorganisms are offering great frontier in explaining the crucial native interaction within the molecules which could help in protein engineering. In this review, the thermostability prospect of lipases and the utility of protein engineering insights into achieving functional industrial usefulness at their high temperature habitat are highlighted. Similarly, the underlying thermodynamic and structural basis that defines the forces that stabilize these thermostable lipase is discussed. KEY POINTS: • The dynamics of lipases contributes to their non-covalent interactions and structural stability. • Thermostability can be enhanced by well-established genetic tools for improved kinetic efficiency. • Molecular dynamics greatly provides structure-function insights on thermodynamics of lipase.
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- 2021
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15. Forecasting Air Pollution with Sulfur Dioxide Emitted from Burning Desulfurized Diesel Using Artificial Neural Network
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Eman Abdelhafez, Mohammad O. Hamdan, and Reyad Shawabkeh
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Environmental Engineering ,Waste management ,Artificial neural network ,Ecology ,air pollution ,Air pollution ,Environmental Science (miscellaneous) ,medicine.disease_cause ,desulfurized diesel ,chemistry.chemical_compound ,Diesel fuel ,chemistry ,medicine ,Environmental science ,sulfur dioxide ,activated carbon ,Sulfur dioxide ,QH540-549.5 ,Activated carbon ,medicine.drug - Abstract
Concentrations of emitted pollutants in the atmosphere are influenced by the emission sources and metrological data. In Jordan, Diesel fuel is considered to be a main source of SO2, which has negative impact on air quality. In this work, the emitted SO2 during the burning of desulfurized diesel fuel using activated carbon is conducted using three types of Artificial Neural Network (Elman, NARX and Feedforward models). To accomplish this, previously experimental work on desulfurization of diesel fuel using two types of activated carbon was adopted. Metrological data involving the average daily temperature (T), relative humidity (RH), wind speed (WS), pressure (P), concentration of Particulate Matter (PM10) and average daily solar radiation (SR) over the period from 2/1/2020 to 30/12/2020. It was found that NARX model is the most accurate model in the furcating process of SO2, flowed by Elman and feedforward was found to be the least capable model in predicting the SO2 emitted concentration.
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- 2021
16. Salvadora persica protects libido by reducing corticosterone and elevating the testosterone levels in chronic cigarette smoke exposure rats
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Salman Mohammed Afroz, Sultan Sajid, Yahya Mohzari, Abdulhakeem S. Alamri, Walaa F. Alsanie, Vasudevan Mani, Abdulmajead Khalid Alanazi, Ahmed A. Alrashed, Farhana Yasmin, Rakan Fahad Alamer, Majid Alhomrani, Syed Imam Rabbani, Hamdan Najib Alajami, Syed Mohammed Basheeruddin Asdaq, Omar Khan, and Awad Othman Aljohani
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medicine.medical_specialty ,QH301-705.5 ,Libido ,Decoction ,chemistry.chemical_compound ,Salvadora persica ,Corticosterone ,Internal medicine ,medicine ,Biology (General) ,Testosterone ,biology ,business.industry ,Cigarette smoke ,biology.organism_classification ,Endocrinology ,chemistry ,Phytochemical ,Original Article ,Analysis of variance ,Hormone levels ,General Agricultural and Biological Sciences ,business ,Hormone ,Phytoconstituents - Abstract
Background & Objectives: Cigarette smoke is associated with several diseased states including defects in reproductive behavior. Salvadora persica (S. persica) known as the toothbrush plant is reported to possess several pharmacological properties including antidepressants and anxiolytics. The present research was done to determine the libido-protective effect of S. persica in chronic cigarette smoke-exposed rats. Materials and Methods: The decoction of freshly dried roots of S. persica (50, 100, and 200 mg/kg, oral) was administered to the chronic-cigarette smoke-exposed adult rats. The parameters related to libido were recorded using a close-camera circuit (CCTV). Serum corticosterone and testosterone levels were estimated. Further, the phytochemical constituents were identified in the decoction. The data obtained were analyzed using one-way analysis of variance and significance was considered at p
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- 2021
17. Toxic Gas Response for Nanostructured Cobalt Oxide Thin Films
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Iftikhar M. Ali, Isam M. Ibrahim, and Suhad A. Hamdan
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Materials science ,chemistry ,Doping ,Oxidizing agent ,chemistry.chemical_element ,Yttrium ,Crystallite ,Thin film ,Cobalt oxide ,Layer (electronics) ,Hydrothermal circulation ,Nuclear chemistry - Abstract
The gas sensing properties of undoped Co3O4 and doped with Y2O3 nanostructures were investigated. The films were synthesized using the hydrothermal method on a seeded layer. The XRD, SEM analysis and gas sensing properties were investigated for the prepared thin films. XRD analysis showed that all films were polycrystalline, of a cubic structure with crystallite size of (12.6) nm for cobalt oxide and (12.3) nm for the Co3O4:6% Y2O3. The SEM analysis of thin films indicated that all films undoped Co3O4 and doped possessed a nanosphere-like structure. The sensitivity, response time and recovery time to H2S reducing and NO2 oxidizing gases were tested at different operating temperatures. The resistance changed with exposure to the test gas. The results revealed that the Co3O4:6%Y2O3 possessed the highest sensitivity around 90% (at room temperature) and 62.5% (at 150 oC) when exposed to the reducing gas H2S and oxidizing gas NO2, respectively with 0.8sec for both recovery and response times.
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- 2021
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18. Pyrolysis of azetidinones. Part 2. kinetics and mechanism of thermolysis of β-lactams and β-thiolactams
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Al-Hamdan, Nouf S., Al-Etaibi, Alya M., Al-Bashir, Rasha F., Ibrahim, Yahia A., Al-Awadi, Nouria A., and El-Dusouqui, Osman M.E.
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Beta lactamases -- Chemical properties ,Pyrolysis -- Observations ,Chemical reaction, Rate of -- Observations ,Chemistry - Abstract
Abstract: The kinetics of the gas-phase thermolysis reaction of seven β-lactams and their thione analogues were investigated over the temperature range 533-603 K for the β-lactams and 463-542 K for [...]
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- 2016
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19. Chromium Elimination from Contaminated Soil by Electro kinetic Remediation, Using Garlic Peels Powder
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Ali Omran Al-Sulttani, Nagam Obaid Kariem, and Laith Hamdan Hawal
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Chemistry ,Environmental remediation ,chemistry.chemical_element ,Soil contamination ,Environmental technology. Sanitary engineering ,soil ,Environmental sciences ,Chromium ,Environmental chemistry ,garlic peels powder ,GE1-350 ,chromium ,removal percentage ,electro-kinetic ,Ecology, Evolution, Behavior and Systematics ,TD1-1066 ,General Environmental Science - Abstract
In this paper, an electro-kinetic technique was applied to remove chromium from contaminated soil. This technique is appropriate for the soils with low permeability. Various experiments were carried out under different operating conditions, including various purging solutions. Garlic peels powder (GPP) was used in this study as a cheap adsorbent substance to avert the flow of reverse osmosis, which may affect the removal percentage. The results proved that the removal percentage increased as the pH of the purging solutions decreased. The first three experiments were performed with purging solution at pH of 4, 6, and 8 respectively. The highest removal percentage was 66.3% at pH of 4 compared to the other two experiments at pH of 6 and 8, where the removal percentages were 53.3% and 49.7%, respectively. This paper showed that the percentage of chromium removal decreased along with the voltage. The removal percentage at 1.5 V/cm was 66.3%, while at 1 V/cm was 61%. Garlic peels powder (GPP) is considered as an effective adsorbent material to avert the reverse osmosis flow. Therefore, the use of this material in this study will give a new impression on the application of these products as an absorbent medium.
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- 2021
20. ANALYSIS OF MOISTURE CONTENT, CALORIFIC VALUE AND BURNING RATE OF CORNCOB AND KAPOK RANDU (Ceiba pentranda) SKIN BRIQUETTE
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Sheilla Rully Anggita, Hamdan Hadi Kusuma, and Anshori Huroeroh
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Briquette ,biology ,RANDU ,Ceiba ,Chemistry ,Carbonization ,Corncob ,biology.organism_classification ,Animal science ,General Earth and Planetary Sciences ,Heat of combustion ,Composition (visual arts) ,Water content ,General Environmental Science - Abstract
Bio charcoal Briquette is a product made from biomass with a carbonization process and compressed with a certain shape. This study aims to examine the calorific value and burning rate of corncob and kapok randu (Ceiba Pentranda) randu (Ceiba pentranda) skin briquettes with variations in the composition of ingredients. The briquette were produced in 5 stages: First, the main material for cobs and kapok randu (Ceiba Pentranda) randu skin is dried in the sun for 3 days so that the weight of the ingredients is reduced by 20%. Second, the carbonization of the main material with a temperature of 400˚C for 60 minutes with a furnace and then materials that has been crushed is sieved with a sieve 50 mesh. Third, compressed briquettes with corncob composition and kapok randu (Ceiba Pentranda) skin in the following ratios of A (100%: 0%), B (75%: 25%), C (50%: 50%), D (25%: 75 %), E (0%: 100%) with 10% w/w tapioca starch as binder. Fourth, the dry the briquette under the sun for 3 days (20 hours) and roasted with a temperature of 100˚C for 60 minutes. Fifth, after dried, the samples were then characterized their moisture content, calorific value, and burning rate. The results show that the highest moisture content value in sample E is 3.3303% and the lowest moisture content in sample B (2.4587%). The highest calorific values are sample E which is 6195.05 Cal / grams. While the lowest calorific value was found in sample D (25% corn cobs and 75% kapok randu (Ceiba Pentranda) skin), which was 3803.96 Cal / grams. The lowest burning rate was found in sample E (100% kapok randu (Ceiba Pentranda) skin) with a value was 0.0448 grams / minute. While the highest burning rate was found in sample D (25% corn cobs and 75% kapok randu (Ceiba Pentranda) skin) with the value was 0.0622 grams/minute.
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- 2021
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21. Prediction of compounds with antiosteoporosis activity in Chrysophyllum cainito L. leaves through in silico approach
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Achmad Hamdan Yuwafi, Fidia Rizkiah Inayatillah, Meilina Ratna Dianti, Luqman Alfani Najib, Burhan Ma'arif, Hening Laswati, Mangestuti Agil, Nisfatul Lailatus Saidah, Hilwa Fitri, and Ria Ramadhani Dwi Atmaja
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Pharmacology ,chemistry.chemical_classification ,Agonist ,0303 health sciences ,biology ,Physiology ,Chemistry ,medicine.drug_class ,In silico ,General Medicine ,biology.organism_classification ,Amino acid ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Biochemistry ,Docking (molecular) ,Chrysophyllum ,030220 oncology & carcinogenesis ,Drug Discovery ,medicine ,Phytoestrogens ,Pharmacophore ,030304 developmental biology ,Discovery Studio - Abstract
Objectives Estrogen deficiency causes various health problems in postmenopausal women, including osteoporosis. Phytoestrogen emerged as a potential alternative of estrogen with minimum side effects. The aims of this study were to analyze the metabolite profiling results of various extract of Chyrsophyllum cainito L. leaves, which contain phytoestrogen, through in silico study against 3OLS protein, an X-ray protein of ERβ, so it can predict the types of the phytoestrogen contents which have antiosteoporosis property. Methods In silico analysis was carried out for the compounds from the metabolite profiling data of C. cainito leaves from our previous study. The structure compounds from metabolite profiling results of various extract of C. cainito leaves were prepared with Avogadro 1.0.1 software, molecular docking was done using PyRx 0.8 software, and Biovia Discovery Studio Visualizer 2016 software was used to visualize the structure of compounds against 3OLS protein. The physicochemical characteristics of the compounds were analyzed using the SwissADME web tool. Results From in silico studies, it was known that there were total 11 compounds in C. cainito leaves that predicted as phytoestrogens which have ERβ agonist properties against 3OLS protein. The ERβ agonist was a compound that has parameters similar to 17β-estradiol in its interaction with 3OLS protein, which has a pharmacophore distance of 10.862 Å, and binding to amino acids His 475 and Glu 305 or Arg 346 at receptor-ligand docking simulation. Conclusions C. cainito leaves contain 11 compounds that are predicted to be phytoestrogens with ERβ agonist properties, which is responsible for antiosteoporosis activity.
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- 2021
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22. The effect of Camellia sinensis (green tea) with its active compound EGCG on neuronal cell necroptosis in Rattus norvegicus middle cerebral artery occlusion (MCAO) model
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Abdulloh Machin, Ramidha Syaharani, Muhammad Hamdan, Imam Susilo, Djoko Agus Purwanto, and Dyah Fauziah
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0301 basic medicine ,Pharmacology ,Physiology ,Necroptosis ,Cell ,General Medicine ,Green tea extract ,Epigallocatechin gallate ,Green tea ,03 medical and health sciences ,chemistry.chemical_compound ,030104 developmental biology ,0302 clinical medicine ,medicine.anatomical_structure ,chemistry ,Active compound ,In vivo ,Drug Discovery ,medicine ,Camellia sinensis ,030217 neurology & neurosurgery - Abstract
Objectives To determine the inhibition effect of epigallocatechin gallate (EGCG) and green tea extract on neuronal necroptosis based on necroptosis morphology. Methods In vivo study was performed on male Rattus norvegicus middle cerebral artery occlusion (MCAO) model divided into five groups, MCAO-control groups, EGCG 10 mg/kg BW/day, EGCG 20 mg/kg BW/day, EGCG 30 mg/kg BW/day, and green tea extract 30 mg/kg BW/day for 7 days treatment. MCAO model was made by modification method using Bulldog clamp. After 7 days of treatment, all R. norvegicus were sacrificed. After that, examination using Hematoxylin–Eosin stain was conducted to look at necroptosis morphology in each group. Results We found that there are significant differences between control group and the other three groups (EGCG 20 mg/kg BW/day, EGCG 30 mg/kg BW/day, and green tea extract (p Conclusions Camellia sinensis (green tea) with its active compound EGCG decreases neuronal necroptosis morphology in MCAO models.
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- 2021
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23. Pharmacokinetic and pharmacodynamic interaction of Rosuvastatin calcium with guggulipid extract in rats
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Yahya Mohzari, Assil Najib Alajmi, Ahmed A. Alrashed, Abdullah Ali Al Mushtawi, Mohammed Asad, Hamdan Najib Alajami, Syed Mohammed Basheeruddin Asdaq, Raha Orfali, Awad Othman Aljohani, Mohd. Imran, and Hanan Nageeb Alajmi
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0106 biological sciences ,0301 basic medicine ,Interaction ,QH301-705.5 ,Cmax ,Pharmacokinetic ,Absorption (skin) ,Pharmacology ,01 natural sciences ,Rosuvastatin ,03 medical and health sciences ,chemistry.chemical_compound ,Pharmacokinetics ,medicine ,Biology (General) ,Pharmacodynamic ,Lipid ,Bioavailability ,Rosuvastatin Calcium ,030104 developmental biology ,chemistry ,Guggulipid ,Pharmacodynamics ,Original Article ,Guggulsterone ,General Agricultural and Biological Sciences ,010606 plant biology & botany ,medicine.drug - Abstract
Background & objectives Rosuvastatin calcium (RC) is a potent and competitive synthetic inhibitor of HMG-CoA reductase used for the treatment of dyslipidemia. Guggulipid obtained from Commiphora mukul is used in the treatment of a wide variety of diseases such as atherosclerosis, hypercholesterolemia, rheumatism, and obesity. The present study evaluates the pharmacokinetic and pharmacodynamic interactions between RC and the standardized guggulipid extract in rats. Materials and methods The guggulipid extract was standardized for the presence of guggulsterones. The pharmacokinetic interaction was determined after a single dose administration of RC alone or in combination with the guggulipid extract or after multiple-dose administration of RC alone or RC along with the guggulipid extract for 14 days. To determine the pharmacodynamic interaction, RC and guggulipid extract were administered to hyperlipidemic rats for 14 days. The level of significance was determined using unpaired student’s t-test, one way ANOVA, the post-ANOVA Tukey test. Results Standardization of guggulipid extract showed it contains 7.5%w/w of guggulsterones. Guggulipid extract increased the bioavailability of RC in both single-dose and multiple-dose studies. Guggulipid extract reduced the rate of absorption (Ka) of RC but showed an increase in maximum serum concentration (Cmax). An in-vitro study using isolated rat intestine revealed that guggulipid extract decreased the rate of absorption of RC in the intestinal lumen. The hypolipidemic activity of RC was augmented by the guggulipid extract in hyperlipidemic rats. Interpretation & conclusion Therefore it is concluded that guggulipid extract increases the bioavailability of RC by delaying its Ka and augments its hypolipidemic action. However, it is recommended that a combination of RC with guggulipid extract should be used only after an adverse effect(s) of this combination are determined.
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- 2021
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24. Echinops taeckholmiana Amin: Optimization of a Tissue Culture Protocol, Biological Evaluation, and Chemical Profiling Using GC and LC-MS
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Dalia I. Hamdan, Marwa A. A. Fayed, and Rasha Adel
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Echinops ,Chromatography ,biology ,Callus formation ,General Chemical Engineering ,Phthalate ,General Chemistry ,Mass spectrometry ,biology.organism_classification ,Tandem mass spectrometry ,Article ,Terpene ,chemistry.chemical_compound ,Tissue culture ,Chemistry ,chemistry ,Liquid chromatography–mass spectrometry ,QD1-999 - Abstract
There have been no reports published on the rare Echinops taeckholmiana growing wildly in Egypt. So, this study aimed to preserve it through method optimization of in vitro seed germination, besides callus formation from induced seedlings. Chemical profiling using gas chromatography-mass spectrometry (GC-MS) analysis of the n-hexane fraction afforded 29 identified components, mainly fatty acids esters, sesquiterpenes, triterpenes, one thiophene, and bis(2-ethylhexyl) phthalate. Ultra-performance liquid chromatography-electron spray ionization/tandem mass spectrometry (UPLC-ESI/MS-MS) analysis of total alcoholic root and induced calli extracts resulted in 68 metabolites. Taraxeryl acetate, β-sitosterol, stigmasterol-3β-d-glucoside, and 1,1,1-kestopentaose were identified from the defatted root extract, which inhibited α-amylase (IC50 54.6 μg/mL) and α-glucosidase (60.4 μg/mL) enzymes compared with acarbose (IC50 values of 30.57 and 34.71 μg/mL, respectively). Moreover, it showed moderate activity against HepG2 (IC50 31.1 ± 1.4 μg/mL) and no activity against M-NFS-60 cell lines compared to cisplatin (IC50 3.25 ± 1.4 and 8.37 ± 0.25, respectively).
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- 2021
25. Electro-Kinetic Remediation of Nickel from Contaminated Soil Using Bio remedies Banana Peels and Surfactant-Enhanced
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Laith Hamdan Hawal, Serror Atta Allah, and Lubna Al-Zubaidi
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Environmental remediation ,chemistry.chemical_element ,Environmental technology. Sanitary engineering ,Soil contamination ,removal efficiency ,soil ,Environmental sciences ,nickel ,Nickel ,bp ,chemistry ,Pulmonary surfactant ,Environmental chemistry ,aot ,GE1-350 ,electro-kinetic ,TD1-1066 ,Ecology, Evolution, Behavior and Systematics ,General Environmental Science - Abstract
Pollution of the soil by different types of heavy metals is one of the most important problems of the environment. The present study used an electro-kinetic remediation, which is one of the important advanced techniques for the removal nickel from contaminated sandy soil. The study includes many experiments with different pH electrode purging solutions (distilled water at pH of 3, 5 and 7). Anionic surfactant (sodium dioctyl sulfosuccinate, AOT) was used for washing soil as surfactant-enhanced remediation. Bio remedies banana peels (BP) were utilized as eco-friendly, low cost and adsorbent materials to avoid reverse osmosis that effects on the removal process. The results indicated that the greatest removal efficiency (65.2%) was achieved at the pH of purging solution (3) in comparison with pH of (5 and 7). This means that when the pH of the purging solution decreases, the removal efficiency increases. Using AOT as a soil-washing solution increased nickel dissolution and desorption from surface of the soil. Then, the AOT micelles containing nickel easily migrated to the cathode chamber by flow of the electro osmotic; thus, the removal efficiency increased (74.8%). In conclusion, the use of AOT is effective in enhancing nickel removal through the electro kinetic remediation. Bio remedies using banana peels is considered as a successful adsorbent material to avoid the reverse osmosis flow, this will give a new thought for the application these products as adsorption medium.
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- 2021
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26. Vigilant: An Engineered VirD2-Cas9 Complex for Lateral Flow Assay-Based Detection of SARS-CoV2
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Ahmed Mahas, Muhammad Tehseen, Magdy M. Mahfouz, Tin Marsic, Samir M. Hamdan, and Zahir Ali
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Letter ,Bioengineering ,02 engineering and technology ,Sensitivity and Specificity ,dCas9 ,molecular diagnostics ,chemistry.chemical_compound ,Biotin ,medicine ,Humans ,General Materials Science ,Polymerase ,VirD2 ,medicine.diagnostic_test ,biology ,SARS-CoV-2 ,Chemistry ,Oligonucleotide ,Cas9 ,nucleic acid detection ,Mechanical Engineering ,COVID-19 ,Nucleic acid test ,lateral flow assay ,Reverse Transcription ,General Chemistry ,biosensors ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,Molecular diagnostics ,Molecular biology ,relaxases ,Biotinylation ,Nucleic acid ,biology.protein ,RNA, Viral ,CRISPR-Cas Systems ,RT-RPA ,CRISPR-Cas9 ,0210 nano-technology - Abstract
Rapid, sensitive, and specific point-of-care testing for pathogens is crucial for disease control. Lateral flow assays (LFAs) have been employed for nucleic acid detection, but they have limited sensitivity and specificity. Here, we used a fusion of catalytically inactive SpCas9 endonuclease and VirD2 relaxase for sensitive, specific nucleic acid detection by LFA. In this assay, the target nucleic acid is amplified with biotinylated oligos. VirD2-dCas9 specifically binds the target sequence via dCas9 and covalently binds to a FAM-tagged oligonucleotide via VirD2. The biotin label and FAM tag are detected by a commercially available LFA. We coupled this system, named Vigilant (VirD2-dCas9 guided and LFA-coupled nucleic acid test), to reverse transcription-recombinase polymerase amplification to detect SARS-CoV2 in clinical samples. Vigilant exhibited a limit of detection of 2.5 copies/μL, comparable to CRISPR-based systems, and showed no cross-reactivity with SARS-CoV1 or MERS. Vigilant offers an easy-to-use, rapid, cost-effective, and robust detection platform for SARS-CoV2.
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- 2021
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27. BiVO4/Cs2PtI6 Vacancy-Ordered Halide Perovskite Heterojunction for Panchromatic Light Harvesting and Enhanced Charge Separation in Photoelectrochemical Water Oxidation
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Niket S. Kaisare, Aravind Kumar Chandiran, Muhammed Hamdan, Manishankar Velpula, and Jayanthan P. Jayaraman
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Materials science ,integumentary system ,Photoelectrochemistry ,Oxide ,Halide ,Heterojunction ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Photochemistry ,01 natural sciences ,0104 chemical sciences ,chemistry.chemical_compound ,chemistry ,Vacancy defect ,Bismuth vanadate ,Water splitting ,General Materials Science ,0210 nano-technology ,Perovskite (structure) - Abstract
Photoelectrochemical water oxidation is a challenging reaction in solar water splitting due to the parasitic recombination process, sluggish catalytic activity, and electrode stability. Oxide semic...
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- 2021
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28. Biological treatment of hazardous heavy metals by Streptomyces rochei ANH for sustainable water management in agriculture
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Nevine B. Ghanem, Heba Alla Farid Abdelmageed, and Amira M. Hamdan
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Chromium ,0301 basic medicine ,Agricultural Irrigation ,Environmental remediation ,Science ,Biomass ,Wastewater ,010501 environmental sciences ,Microbiology ,01 natural sciences ,Lepidium sativum ,Article ,Water Purification ,03 medical and health sciences ,Bioremediation ,Effluent ,0105 earth and related environmental sciences ,Multidisciplinary ,Chemistry ,Biosorption ,Streptomyces ,Spore ,Environmental sciences ,Biodegradation, Environmental ,030104 developmental biology ,Germination ,Environmental chemistry ,Medicine ,Water quality ,Water Pollutants, Chemical - Abstract
Microbial bioremediation of heavy metals-polluted industrial effluents has been adopted as one of the most effective eco-friendly tool to cope up with the harmful effects of metals. This study was designed to investigate the biosorption potential of marine actinomycetes isolated from the Alexandrian Mediterranean Seacoast, Egypt, with their potential use in metal remediation of industrial effluents. Among the nine marine actinomycetes isolates, Streptomyces rochei ANH showed the highest versatile metal resistance capability with MIC values of 125 mg/l for Cr6+ and 60 mg/l for both Cd2+ and Pb2+. Additionally, scanning electron micrographs showed complete disintegration of Cr6+-treated biomass compared with the control ones where spores remained intact and connected in long chains. The study also aimed to improve the percentage of Cr6+ biosorption by S. rochei ANH biomass using the statistical designs of Plackett–Burman and Box-Behnken where up to 85% of Cr6+ removal was recorded under the following conditions: pH (5), incubation temperature (30 °C), contact time (3 h), agitation speed (90 rpm), initial Cr6+ concentration (50 mg/l) and living biomass concentration (10 mg/ml). The results also showed that the percentage of Cr6+ biosorption by S. rochei ANH decreased gradually beyond these values. Moreover, the results revealed that the use of the biomass of S. rochei ANH is an effective biotechnological agent for the biological treatment of heavy metal-contaminated tannery effluent where the percentages of metal removal were in the following order: Ni2+ (100%) ≥ Cu2+ ≥ Mn2+ ≥ Fe2+ > Pb2+ (95%) ≥ Cd2+ > Cr6+ (86%). Furthermore, the treated effluent exhibited a stimulating effect on the germination process of Lepidium sativum seeds. Therefore, the present study implies that S. rochei ANH can be considered a powerful candidate to mitigate hazardous heavy metals pollution from industrial effluents and improve the water quality for agricultural purposes.
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- 2021
29. EFFICACY OF PENTAVALENT ANTIMONIAL INJECTION IN IMPROVING THE OXIDATIVE, NITROSATIVE STATUS AND IMMUNE CELLULAR ENZYME ACTIVITY IN TREATING SAUDI PATIENTS WITH CUTANEOUS LEISHMANIASIS
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Mossad A. Saif, Abdullah D. Alanazi, Aishah E. Albalawi, and Hamdan I Al-Mohammed
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chemistry.chemical_classification ,biology ,business.industry ,Glutathione peroxidase ,Glutathione ,Pharmacology ,Malondialdehyde ,medicine.disease ,Pentavalent antimonial ,Lipid peroxidation ,chemistry.chemical_compound ,chemistry ,Cutaneous leishmaniasis ,Myeloperoxidase ,biology.protein ,Medicine ,business ,Reactive nitrogen species - Abstract
Macrophages, within which Leishmania sp. replicate, generate large amounts of reactiveoxygen species and reactive nitrogen species to kill these parasites. The present study aimed toassess the oxidative and nitrosative stresses and activities of key immune response enzymes inthe serum of patients with cutaneous leishmaniasis (CL) before and after treatment withsodium stibogluconate as well as in the control individuals. Serum activities of superoxidedismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), and levels of reducedglutathione, malondialdehyde (MDA), and nitric oxide (NO) as well as those of L-arginase,myeloperoxidase (MPO), and adenosine deaminase (ADA) were studied. The activities of Larginase,MPO, ADA, and MDA and levels of NO were significantly elevated (P < 0.001),whereas those of SOD, CAT, and GSH-Px and levels of GSH were significantly reduced (P
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- 2021
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30. Comparison and optimization of conventional and ultrasound‐assisted solvent extraction for synthetization of lemongrass ( Cymbopogon )‐infused cooking oil
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B.H. Lim, Sing Ngie David Chua, Adirah Hamdan, and Soh Fong Lim
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food.ingredient ,Citral ,conventional solvent extraction ,01 natural sciences ,lemongrass‐infused cooking oil ,03 medical and health sciences ,chemistry.chemical_compound ,food ,TX341-641 ,Response surface methodology ,Food science ,ultrasound‐assisted solvent extraction ,Solvent extraction ,030304 developmental biology ,0303 health sciences ,Nutrition. Foods and food supply ,010405 organic chemistry ,Sunflower oil ,Extraction (chemistry) ,food and beverages ,lemongrass ,0104 chemical sciences ,infused oil ,Solvent ,chemistry ,Cymbopogon ,optimization ,Corn oil ,Food Science - Abstract
The lemongrass plant, which is widely cultivated in Asia, Australia, and Africa, has been reported to have many significant health benefits such as antimicrobial, insecticide, anticancer, fight fever, and disinfection. Therefore, it is an added benefit to have lemongrass compounds in cooking oil. This study was aimed to compare the conventional (CSE), and ultrasound‐assisted solvent extraction (UASE) for citral compounds from lemongrass (Cymbopogon) leaves and to optimize the best extraction method using the response surface methodology (RSM) and ANOVA. RSM design of experiments using three types of cooking oils; palm oil, sunflower oil, and corn oil. The effect of three independent variables, which are temperature (48.2–81.8°C), extraction time (4.8–55.2 min), and solvent to leaves ratio (5.3–18.7), was investigated. The characterization of lemongrass‐infused cooking oil was evaluated by Fourier transform infrared spectroscopy (FT‐IR), Gas Chromatography‐Mass Spectrometry (GC‐MS) and Scanning Electron Microscopy (SEM) analysis for confirmation of the citral compound extraction. This extraction process is optimized using Response Surface Methodology (RSM) for producing the lemongrass‐infused cooking oil. After optimization, the UASE process gives 1.009 × 106 maximum citral area for palm oil and 1.767 × 106 maximum citral area for sunflower oil. CSE process only can give 2.025 × 105 and 2.179 × 105 citral area in the GC‐MS spectrum for palm oil and sunflower oil respectively. For both the UASE and the CSE, the optimum operating conditions are 81.8°C of extraction temperature and 55.2 min of extraction time except for lemongrass‐infused palm oil in the CSE process with 45 min extraction time. The optimum solvent to leaves ratio varies from 5.3:1 to 12.9:1. This study found that corn oil cannot be used as a solvent to extract lemongrass‐infused cooking oil due to the insignificant changes and no citral peak. The lemongrass (Cymbopogon)‐infused palm oil and sunflower oil extracted using the UASE have a higher maximum citral area than the CSE process.
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- 2021
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31. Oxidative stress, immunological and cellular hypoxia biomarkers in hepatitis C treatment-naïve and cirrhotic patients
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Tarek H. El-Metwally, Omar I. M. Almadhi, Abdulrahman Abdulwahab Alduraywish, Maysa A. Mobasher, Hanan M. Nafeh, and Abdulrahman Hamdan Almaeen
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hepatitis C virus ,medicine.medical_specialty ,Cirrhosis ,Angiogenesis ,liver cirrhosis ,Hepatitis C virus ,medicine.disease_cause ,Chronic liver disease ,Gastroenterology ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Clinical Research ,Internal medicine ,medicine ,oxidative stress ,030212 general & internal medicine ,hypoxia ,business.industry ,chronic liver disease ,General Medicine ,Hepatitis C ,Hypoxia (medical) ,medicine.disease ,Malondialdehyde ,liver enzymes ,chemistry ,immunological changes ,medicine.symptom ,business ,Oxidative stress - Abstract
IntroductionHepatitis C virus (HCV) is the main cause of chronic liver disease, with calamitous complications. Its highest rate is recorded in Egypt. This study investigated whether oxidative stress, immunological chaos and cellular hypoxia are implicated in the pathophysiology of the disease.Material and methodsThis cross-sectional study aimed to evaluate the changes in blood oxidative stress, cellular hypoxia/angiogenesis and cellular immunological biomarkers in hospital-diagnosed treatment-naïve HCV-infected Upper Egyptian chronic liver disease patients vs. healthy controls (n = 40). The consecutively included patients comprised 120 with normal serum enzymes (HCV-NE) and 130 with high serum enzymes (HCV-HE), along with 120 cirrhotic patients.ResultsOxidative stress biomarkers – malondialdehyde (MDA), total peroxides and oxidative stress index (OSI) – were significantly lower in controls vs. each of the patient groups. Cirrhotic patients presented the highest levels. However, total antioxidants (TAO) showed non-significant differences among the four groups. The cellular hypoxia/angiogenesis biomarkers – lactate, vascular endothelial cell growth factor (VEGF) and its soluble receptor 1 (sVEGFR1) – vs. controls were massively increased in patient groups. VEGF was lowest while sVEGFR1 was highest among cirrhotic patients. Immunological biomarkers, – granulocyte/monocyte-colony stimulating factor (GM-CSF) and total immunoglobulin G (IgG) – were massively increased in patient groups vs. controls. GM-CSF was lowest in HCV-HE and IgG was highest in cirrhotic patients. sVEGFR1 correlated with the progression towards cirrhosis.ConclusionsOxidative stress is implicated in the progress of HCV infection with marked induction of cellular hypoxia and dysfunctional angiogenesis, and a futile immunological reaction. sVEGFR1 level correlated with progression towards HCV-induced liver fibrosis.
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- 2021
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32. Veratraldehyde as a food additive produced by the marine isolate Streptomyces diastaticus LC360811
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Hasnaa B. Ghoneim, Amira M. Hamdan, Moustafa Y. El-Naggar, Mohamed A. Aly-Eldeen, and Khouloud M. Barakat
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biology ,Veratraldehyde ,Streptomyces diastaticus ,Aquatic Science ,biology.organism_classification ,medicine.disease_cause ,Antimicrobial ,Aeromonas hydrophila ,chemistry.chemical_compound ,chemistry ,Staphylococcus aureus ,medicine ,Fermentation ,Streptococcus iniae ,Food science ,Bacteria - Abstract
Twelve actinomycete isolates were derived from 6 sediment samples collected from the Red Sea coast, Egypt. The marine isolate, RS10, the most potent candidate, proved its capability to produce antimicrobial compound(s) that strongly inhibit both Gram-positive and Gram-negative bacteria. RS10 was identified by 16S rRNA gene sequencing as Streptomyces diastaticus LC360811. Culture supernatant of S. diastaticus LC360811 was extracted using n-butanol and tested against bacterial indicator strains using the disc diffusion method. The crude extract was partially purified using column chromatography and assessed for antimicrobial activity. Fraction no. 35 showed the highest antimicrobial activity against Acinatobacter sp. (34 mm), Pseudomonas aeruginosa ATCC 9027 (30 mm), Candida albicans (26 mm), Staphylococcus aureus ATCC 47077 (25 mm), Aeromonas hydrophila (23 mm),Streptococcus iniae (22 mm)and Borditella sp. (18 mm). This active fraction was then identified as veratraldehyde using spectroscopic techniques: GC-MS-MS and HPLC (diode array detector) and compared with the authentic reference. Veratraldehyde as a natural preservative proved to be a good candidate to preserve the flavor of juice, yogurt, and fermented milk and was able to control the growth of bacterial pathogens compared to the non-treated products till day fourteen.
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- 2021
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33. Scaffolds Materials from Gellan Gum Incorporated Ball Clay as Dressing Materials
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Nur Masyitah Hamdan and Khairul Anuar Mat Amin
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Materials science ,Mechanical Engineering ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,01 natural sciences ,Gellan gum ,0104 chemical sciences ,chemistry.chemical_compound ,chemistry ,Mechanics of Materials ,Wound dressing ,General Materials Science ,Composite material ,0210 nano-technology ,Ball clay - Abstract
The demand for wound management treatment especially advanced and active wound care products is huge. In this study, the scaffolds were prepared from gellan gum (GG) incorporated ball clay (BC) at different concentrations to investigate their swelling properties, water vapor transmission rates (WVTR), mechanical characteristic and thermal behavior. There are three different concentrations of BC were added into the GG scaffolds which were 5% w/w (GG/BC5), 10% w/w (GG/BC10) and 15% w/w (GG/BC15). Swelling ratio of GG scaffolds were increased upon addition of ball clay, while WVTR values of all scaffolds were decreased in the range of 1081–1164 g m−2 d−1. The mechanical performance results show that the GG/BC10 has the highest compressive stress at break (26 ± 5 MPa) and compressive strain at break (110 ± 21%). For thermal behavior, it shows that the thermal stability of GG scaffolds had improved after the addition of ball clay attributed to the interaction between GG and ball clay. The results show that the GG/BC scaffolds could be a potential candidate to be used as an active wound care product.
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- 2021
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34. Improving the Tensile Properties of Curcuma Mangga Val Extract (CMVE)/PVA Nanofiber Mats by Using a Type of Non-Commercial CMVE
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Ardhia Revarti, Harini Sosiati, Angga Ardinista, M. Dirga Rianto, Kunto Wandono, and Sinin Hamdan
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Non commercial ,Chemistry ,Mechanical Engineering ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Electrospinning ,0104 chemical sciences ,Mechanics of Materials ,Nanofiber ,Ultimate tensile strength ,General Materials Science ,Curcuma mangga ,Composite material ,0210 nano-technology - Abstract
The commercially available Curcuma mangga Val extract (CMVE) and poly (vinyl alcohol) (PVA) blends were studied by electrospinning. The result showed inadequate tensile properties of commercial CMVE/PVA nanofiber mats with very high modulus (220.0 MPa) and low strain (50%). The commercial CMVE was then replaced by a type of non-commercial CMVE to compare them with those of the commercial bandage. A non-commercial CMVE was prepared by simply extracting of the fresh Curcuma mangga Val (CMV) produced in a liquid extract. This non-commercial CMVE was then blended with 10% (w/w) PVA at various concentrations of CMVE (0, 2, 5, 10 and 15%) (w/w). The morphology and tensile properties of the mats were investigated. The findings indicated that the tensile strength and modulus increased with CMVE concentrations, decreased of the mean fiber diameter. In this study, a nanofiber mat with a concentration of 2% CMVE was selected and compared to others. This mat had lower average fiber diameter (187.50 nm), tensile strength (8.93 ± 0.36 MPa) and modulus (31.37 ± 4.91MPa), and higher tensile strain (90%) than the commercial CMVE/PVA. Compared to the tensile properties of the Hansaplast bandage, the current tensile strength was higher, the tensile modulus was equivalent and lower tensile strain.
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- 2021
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35. Antinociceptive effect, acute toxicity and chemical analysis of cold mechanically extracted N. Sativa seed oil
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A M Abdulghani Mahfoudh, Muhammad Bala Yauri, Anwar Md Jamir, Ahmed Saeed Mohammed Ali, Hamdan Mohammad Razak, and Al-Naggar Redhwan Ahmed
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Nociception ,Chemistry ,General Engineering ,General Earth and Planetary Sciences ,Pharmacology ,Acute toxicity ,General Environmental Science - Abstract
Nigella sativa L. (Ranunculaceae), seed oil is traditionally used for pain, stiffness in the joints and eczema. The N. sativa seed oil (NSSO) contains an abundance of monoterpenes and essential fatty acids of various pharmacological actions. The objective of this study is to investigate the antinociceptive effect of single oral dose of NSSO on acetic acid-induced writhing and hot plate induced algesia in mice. Further, the study also, aims to characterize the chemical constituents of NSSO by using GC/MS. Swiss albino mice were divided into two sets of three groups consisting of six animals per group for the assessment of analgesic effect by hot plate and by acetic acid induced writhing methods. Group I, received distilled water (10 ml/kg, p.o.); group II, received diclofenac sodium (2.5 mg/100g, p.o.); and group III, received NSSO (0.5 ml/100g, p.o.). After NSSO administration the animals were placed on the hot plate and their response was noted down at different time interval. Further, another set of animals of other three groups were subjected to acetic acid induced writhing test after 30 minutes of drug administration. The results of the study showed that NSSO significantly (p
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- 2022
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36. Effect of Stacking Sequences, Fabric Orientations, and Chemical Treatment on the Mechanical Properties of Hybrid Woven Jute–Ramie Composites
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M. H. M. Hamdan, Januar Parlaungan Siregar, Ahmed Nurye Oumer, M. Zalinawati, C. Tezara, Jamiluddin Jaafar, and K. H. Chuah
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chemistry.chemical_classification ,0209 industrial biotechnology ,Materials science ,Renewable Energy, Sustainability and the Environment ,Chemical treatment ,Mechanical Engineering ,Stacking ,Vinyl ester ,02 engineering and technology ,Polymer ,021001 nanoscience & nanotechnology ,Industrial and Manufacturing Engineering ,Ramie ,020901 industrial engineering & automation ,chemistry ,Flexural strength ,Management of Technology and Innovation ,Ultimate tensile strength ,Low density ,General Materials Science ,Composite material ,0210 nano-technology - Abstract
Natural fibres have been widely used in advanced applications, especially in the automotive industry. These fibres are inexpensive, non-abrasive, environmentally friendly, biodegradable, and possess low density with good mechanical properties. The main issue in using natural fibres is their incompatibility with a polymer matrix that lowers the mechanical properties. Therefore, this research analyses the effect of stacking sequences, fibre orientations, and alkali treatment on the mechanical properties of hybrid jute (J) and ramie (R) reinforced vinyl ester (VE) composites. Initially, woven fibres were fabricated based on the 3 and 4—layer stacking sequence with 0° orientation. The characterisation was done to analyse its properties. It was found that the RJJR stacking sequence possessed a tensile strength higher value of 28.90 MPa. The results for the RJJR sequence were fabricated with various fibre orientations such as 0°, 30°, 45°, and 90° to understand the effect of fibre orientation towards the tensile and flexural properties. The tensile and flexural strength with 0° fibre orientation is significantly higher than the other orientations with values of 28.90 MPa and 66.81 MPa, respectively. Besides, alkali treatment with 5 wt.% and 10 wt.% was used to enhance the mechanical properties, where 0° RJJR with 5 wt.% indicated maximum flexural strength with 34.50% increment compared to untreated RJJR. In conclusion, the combination of fibre orientation and lower alkali treatment concentration (5 wt.%) is highly beneficial in improving fibre hybrid composites' mechanical properties.
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- 2021
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37. Bioinspired Early Divergent Oxidative Cyclizations toward Pleiocarpamine, Talbotine, and Strictamine
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Cyrille Kouklovsky, Guillaume Vincent, Maxime Jarret, Erwan Poupon, Laurent Evanno, Hussein Abou-Hamdan, Institut de Chimie Moléculaire et des Matériaux d'Orsay (ICMMO), Institut de Chimie du CNRS (INC)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Biomolécules : Conception, Isolement, Synthèse (BioCIS), Institut de Chimie du CNRS (INC)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-CY Cergy Paris Université (CY), ANR-15-CE29-0001,Mount-Indole,Escalader des Montagnes en Chimie des Alcaloïdes Indoliques particulièrement Complexes: Méthodologies pour la Synthèse Totale(2015), and ANR-17-CE07-0050,ArDCo,Bisfonctionnalisations désaromatisantes d'arènes(2017)
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Stereochemistry ,Monoterpene ,Oxidative phosphorylation ,010402 general chemistry ,01 natural sciences ,Biochemistry ,Indole Alkaloids ,chemistry.chemical_compound ,Alkaloids ,[CHIM]Chemical Sciences ,Physical and Theoretical Chemistry ,Vinca Alkaloids ,Indole test ,chemistry.chemical_classification ,Molecular Structure ,010405 organic chemistry ,Chemistry ,Organic Chemistry ,3. Good health ,0104 chemical sciences ,Cyclization ,Strictosidine ,Monoterpenes ,Pleiocarpamine ,Oxidation-Reduction ,Tricyclic - Abstract
International audience; Towards the mavacurane and akuammilane monoterpene indole alkaloids, we developed divergent oxidative couplings between the indole nucleus (at N1 or C7) and the C16-malonate of a common tricyclic model related to strictosidine according to a biosynthetic hypothesis postulated by Hesse and Schmid. These oxidative cyclizations lead selectively to the formation of the N1-C16 bond of pleiocarpamine or to the C7-C16 bond of strictamine. We were then able to obtain the scaffold of talbotine.
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- 2021
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38. The role of temperate treed swamps as a carbon sink in southwestern Nova Scotia
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Karen A. Harper, Rachel A. Kendall, Kevin Hamdan, and David L. Burton
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Nova scotia ,Global and Planetary Change ,geography ,geography.geographical_feature_category ,010504 meteorology & atmospheric sciences ,Ecology ,Climate change ,Carbon sink ,chemistry.chemical_element ,Forestry ,Wetland ,04 agricultural and veterinary sciences ,01 natural sciences ,Swamp ,chemistry ,040103 agronomy & agriculture ,Temperate climate ,0401 agriculture, forestry, and fisheries ,Environmental science ,Ecosystem ,Carbon ,0105 earth and related environmental sciences - Abstract
Forested wetlands may represent important ecosystems for mitigating climate change effects through carbon (C) sequestration because of their slow decomposition and C storage by trees. Despite this potential importance, few studies have acknowledged the role of temperate treed swamps in the C cycle. In southwestern Nova Scotia, Canada, we examined the role of treed swamps in the soil C cycle by determining C inputs through litterfall, assessing decomposition rates and soil C pools, and quantifying C outputs through soil greenhouse gas (GHG) emissions. The treed swamps were found to represent large supplies of C inputs through litterfall to the forest floor. The swamp soils had substantially greater C stores than the swamp–upland edge or upland soils. We found growing season C inputs via litterfall to exceed C outputs via GHG emissions in the swamps by a factor of about 2.5. Our findings indicate that temperate treed swamps can remain a C sink even if soil GHG emissions were to double, supporting conservation efforts to preserve temperate treed swamps as a measure to mitigate climate change.
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- 2021
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39. Zeolitic imidazolate framework-L incorporated graphene oxide hybrid for cadmium removal
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Ahmad Fauzi Ismail, Nur Aqilah Mohd Razali, Siti Zu Nurain Ahmad, Rafidah Hamdan, Wan Norharyati Wan Salleh, Nor Hafiza Ismail, and Nurafiqah Rosman
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010302 applied physics ,Cadmium ,Langmuir ,Aqueous solution ,Oxide ,chemistry.chemical_element ,Langmuir adsorption model ,02 engineering and technology ,021001 nanoscience & nanotechnology ,01 natural sciences ,chemistry.chemical_compound ,symbols.namesake ,Adsorption ,chemistry ,0103 physical sciences ,Imidazolate ,symbols ,0210 nano-technology ,Zeolitic imidazolate framework ,Nuclear chemistry - Abstract
The removal of cadmium from wastewater is crucial to avoid its harmful effects on the ecosystem. Thus, in this study, novel composites were prepared by in situ synthesis of zeolitic imidazolate framework-L (ZIF-L) incorporated with graphene oxide (GO) of different loading ratios to produce ZIF-L/GO 20 and ZIF-L/GO 50. The adsorbents were characterized using X-ray Diffractometer (XRD), Fourier-transform Infrared Spectroscopy (FT-IR), and Scanning Electron Microscopy (SEM). The effects of Cd(II) adsorption with respect to the initial pH solution, adsorbent dosage, initial Cd(II) concentration, and contact time were investigated. Both ZIF-L/GO 20 and ZIF-L/GO 50 showed superior performance in removing Cd(II) as compared with ZIF-L (62.32% within 160 min), which were 64.35% and 70.41% within 60 min and 180 min, respectively. The optimum dosage obtained was 0.2 g/L for the removal of 100 mg/L Cd(II) synthetic wastewater. The protruding grains of flower-like ZIF-L/GO 20 allowed for faster adsorption time, whereas the smaller size of irregular shapes ZIF-L/GO 50 increased the surface area for higher adsorption capacity. Also, the adsorption of Cd(II) had fitted well with pseudo-second-order kinetic model and Langmuir isotherm. The Langmuir maximum adsorption capacities for ZIF-L, ZIF-L/GO 20, and ZIF-L/GO 50 were 163.93, 172.42, and 188.68 mg/g, respectively. The novel adsorbents ZIF-L/GO 20 and ZIF-L/GO 50 showed promising performance in the removal of Cd(II) ion from the aqueous solution.
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- 2021
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40. Mechanical properties of hybrid sugar palm/ramie fibre reinforced epoxy composites
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Jamiluddin Jaafar, Januar Parlaungan Siregar, Tezara Cionita, Mohd Ruzaimi Mat Rejab, M. Zalinawati, M. H. M. Hamdan, and I. Mawarnie
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010302 applied physics ,chemistry.chemical_classification ,Materials science ,Composite number ,02 engineering and technology ,Polymer ,Epoxy ,021001 nanoscience & nanotechnology ,01 natural sciences ,Ramie ,chemistry ,Flexural strength ,visual_art ,0103 physical sciences ,Ultimate tensile strength ,visual_art.visual_art_medium ,Composite material ,0210 nano-technology ,Sugar - Abstract
There has been a dramatic increase in natural fibre composites over the past century when natural fibre has performed well as polymer reinforcement. The present study was conducted on the mechanical properties of reinforced epoxy hybrid composites on sugar palm fibre (SPF) (long fibre)/ramie fibre (woven). The hybridizing effect of sugar palm (S) and ramie (R) fibres at different weight ratios was studied at S:R = 15:10 and R:S = 15:10, and thus maintaining the total fibre load by 25% in weight. The composite hybrid specimen consisted of five layers of fibre was prepared alternately. The mechanical properties of composites were analysed by tensile and flexural tests, respectively. The result showed that the tensile and flexural strength of five-layer ramie composite was greater than the five-layer SPF composite. On the RSRSR hybrid composite with higher tensile (52.66 MPa) and flexural (80.70 MPa) strength properties among the five-layer SPF and SRSRS hybrid composites, positive hybridisation effects were observed. Since studies on hybrid composite reinforced long fibre SPF were combined with ramie woven reinforced epoxy to improve mechanical performance, the aim to achieve a green composite has become successful.
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- 2021
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41. Characterization and property investigation of microcrystalline cellulose (MCC) and carboxymethyl cellulose (CMC) filler on the carrageenan-based biocomposite film
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Khairatun Najwa Mohd Amin, Nor Amira Othman, Mohd Aiman Hamdan, Fatmawati Adam, and Nur Amalina Ramli
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010302 applied physics ,Materials science ,food.ingredient ,02 engineering and technology ,021001 nanoscience & nanotechnology ,01 natural sciences ,Gelatin ,Carboxymethyl cellulose ,Carrageenan ,Microcrystalline cellulose ,chemistry.chemical_compound ,Crystallinity ,food ,chemistry ,Chemical engineering ,0103 physical sciences ,Ultimate tensile strength ,medicine ,Cellulose ,Biocomposite ,0210 nano-technology ,medicine.drug - Abstract
Hard capsule has received high demands not only in the pharmaceutical industry but also in food, cosmetics, and personal care applications. Current hard capsule made from gelatin has contributed to the rise of allergy and halal issues. Thus, many researches were looking for alternatives to produce hard capsule from natural and renewable sources such as carrageenan. In this study, carrageenan was incorporated with carboxymethyl cellulose (CMC) and microcrystalline cellulose (MCC) to toughen the carrageenan based biocomposite film and hard capsule. The cellulose filler used was expected to increase the tensile strength and viscosity properties of the carrageenan matrix due to the development of strong hydrogen bonding between the carrageenan and filler. The crystallinity and functional group properties of CMC and MCC were identified via X-ray diffraction (XRD) and Fourier transforms infrared (FTIR) analysis. Then, the hard capsule was prepared by incorporating carrageenan with isovanillin, PEG, alginic acid at different cellulose filler concentrations. The formulation solution was cast for biocomposite film development and dipped for hard capsule development. The tensile strength of the film was analyzed to study the effect of the cellulose filler on the film produced. Crystallinity result shows that CMC is an amorphous while MCC is a crystal, thus CMC has excellent solubility in water compared to MCC. Moreover, film and hard capsule mechanical properties demonstrated that Carra-CMC has the highest tensile strength in comparison to Carra-MCC. Incorporation of CMC in carrageenan biocomposite film shows a significant increment of viscosity up to 50% and the tensile strength up to 37%. The presence of main three functional groups in CMC structure increased the molecular interaction in the carrageenan biocomposite thus improve the film properties. It is predicted that a higher concentration of CMC is required to produce a more stable Carra-CMC biocomposite film and hard capsule.
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- 2021
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42. EFFECT OF ADDING MAGNESIUM SULFATE TO BUPIVACAINE ON ULTRASOUND GUIDED INTERSCALENE NERVE BLOCK
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Anwar Mohamed Mostafa Al-Hassanin, Ragab Asaad Hamdan Mahmoud, and Amr Soliman Hamrosh
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Bupivacaine ,Magnesium ,Local anesthetic ,medicine.drug_class ,business.industry ,medicine.medical_treatment ,chemistry.chemical_element ,Patient satisfaction ,chemistry ,Anesthesia ,Statistical significance ,medicine ,Nerve block ,business ,Brachial plexus ,Saline ,medicine.drug - Abstract
Background: An effective pain therapy to block or modify the physiologic responses to stress has become an essential component of anesthesia for adequate postoperative pain relief. Objective: This work is aimed to evaluate effect of adding magnesium sulfate to long acting local anesthetic as bupivacaine on ultra sound guided inter scalene nerve block undergoing elective upper limb surgery. Patients and Methods: 60 Adult patients were included study and randomized into two equal groups; Magnesium Group received bupivacaine plus magnesium sulfate, and Saline Group received bupivacaine plus normal saline 2 ml. [The demographic data (age, sex, height, weight and ASA scoring) showed no statistical significance between 2 groups]. The time taken to stimulate the brachial plexus and the onset of block were recorded. The regain of sensation and motor power were checked at regular intervals. Patient and surgeon satisfaction were questioned. The study was conducted in Al-Azhar University Hospitals (Al-Hussein and Bab-Shaarya), from December 2019 till June 2020. Results: The duration of sensory and motor block, magnesium group was statistically significant compared to saline group [Mean and (standard deviation 789(135), 788(120) minvs710 (150), 720 (135) min, P= 0.038 vs. 0.042 respectively]. Patient satisfaction was statistically significant in favor to the magnesium group. On the other hand, there was no significant difference in surgeon satisfaction between both groups. Conclusion: The addition of magnesium sulfate to a bupivacaine for interscalene nerve block prolongs the duration of analgesia and reduces postoperative pain.
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- 2021
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43. Preparation, characterization and antimicrobial assessment of selected ciprofloxacin salts
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Rula M. Darwish, Dina El-Sabawi, Lina A. Dahabiyeh, and Imad I. Hamdan
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staphylococcus aureus ,salts ,Pharmaceutical Science ,partition coefficient ,medicine.disease_cause ,030226 pharmacology & pharmacy ,01 natural sciences ,Microbiology ,03 medical and health sciences ,0302 clinical medicine ,ciprofloxacin ,Staphylococcus epidermidis ,medicine ,staphylococcus epidermidis ,Pharmaceutical industry ,Pharmacology ,biology ,Staphylococcus aureus ,Chemistry ,General Medicine ,biology.organism_classification ,Antimicrobial ,0104 chemical sciences ,Ciprofloxacin ,010404 medicinal & biomolecular chemistry ,HD9665-9675 ,medicine.drug - Abstract
The formation of salts is considered a simple strategy to modify the physicochemical properties of active pharmaceutical ingredients. In this study, seven novel binary and ternary organic salts of ciprofloxacin (CP) were prepared with benzoic acid (BA), acetylsalicylic acid (ASA), p-coumaric acid (PCMA) and p-aminosalicylic acid (PASA). They were characterized by spectroscopic techniques and differential scanning calorimetry. Solubility and partition coefficients values were also measured. Evaluation of the antimicrobial activity of the organic salts against Staphylococcus aureus and Staphylococcus epidermidis revealed that most of the new salts had higher antimicrobial activity than CPHCl against both strains. The most active compounds against S. epidermidis and S. aureus were CP-PASA and CPPCMA, resp., which were up to fourteen times more potent than parent CP-HCl. Our findings indicated a strong correlation between the lipophilicity of the formed salts and their antimicrobial activity and showed that an optimum value of lipophilicity (log P = 0.75) seemed to be necessary to maximize the antimicrobial activity. These findings highlighted the improved physical, thermal and antimicrobial properties of the new salts of CP that can aid in providing higher bioavailability than CP-HCl.
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- 2020
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44. The Osteogenetic Potential of Chitosan Coated Implant: An In Vitro Study
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Banna M Alnufaiy, Khalid Al-Hamdan, and Rhodanne Lambarte
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medicine.medical_treatment ,02 engineering and technology ,Cell morphology ,Biochemistry ,Osseointegration ,Chitosan ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,medicine ,Dental implant ,Molecular Biology ,biology ,Chemistry ,Osteoblast ,030206 dentistry ,Cell Biology ,021001 nanoscience & nanotechnology ,medicine.anatomical_structure ,biology.protein ,Osteocalcin ,Implant ,Osteonectin ,0210 nano-technology ,Biotechnology ,Biomedical engineering - Abstract
Objective: Chitosan is a promising polymer that has been used for coating dental implants. However, research concerning coatings with implant surfaces other than commercially pure titanium is limited. Therefore, this study aims to clarify the chitosan material's effect with two degrees of deacetylation (DDA) as coatings for laser surface microtopographic implants. Methods: Sixty-three Laser-Lok (LL) implant discs were divided into three groups (21 in each group), and two groups were coated with either 80 or 95 DDA chitosan. The groups were categorized as LL 95, LL 80, or LL control. Then, hMSC-TERT 20 cells were used to evaluate the cell morphology, viability, and osteogenic capacity of the chitosan material 7 and 14 days after culture. Two-way ANOVA followed by one-way analysis of variance (ANOVA) and Tukey's post hoc test were used. Results: All samples were biocompatible and allowed cell attachment. However, cell spreading and attachment were noticeably increased in the LL 95 group. There was a significant increase in the expression of osteogenic markers in chitosan-coated samples compared to the control group. The 95 DDA-coated group exhibited higher ALP, Runx2, osteocalcin, and osteonectin expression compared to the 80 DDA and control groups on days 7 and 14. Conclusion: A high DDA of chitosan promotes biomineralization and osteoblast formation. Therefore, this combination of laser surface and chitosan can enhance future dental implant healing processes and osseointegration.
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- 2020
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45. Cytotoxic Activity of Cu/TiO2 Nanoparticles on Uterine-Cervical Cancer Cells
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Aida Hamdan-Partida, Miguel Angel Zavala Sánchez, Julia Pérez Ramos, Jaime Bustos-Martínez, Samuel González-García, Emma Elisa Ortiz Islas, and Ruben Del Muro Delgado
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Thermogravimetric analysis ,Materials science ,biology ,Scanning electron microscope ,Kinetics ,Biomedical Engineering ,chemistry.chemical_element ,Nanoparticle ,Bioengineering ,02 engineering and technology ,General Chemistry ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,biology.organism_classification ,Copper ,HeLa ,Differential scanning calorimetry ,chemistry ,General Materials Science ,Fourier transform infrared spectroscopy ,0210 nano-technology ,Nuclear chemistry - Abstract
Nanoparticles based on metal oxides serve as carrier matrices for molecules of biological interest. In this work, we used different copper complexes that were coupled to TiO2 nanoparticles. Nanoparticles were prepared with the sol–gel method. The Cu/TiO2 nanoparticles were characterized through ultraviolet-visible and Fourier transform infrared spectroscopy, differential scanning calorimetry, thermogravimetric analysis, nitrogen physisorption analysis, and scanning electron microscopy. Their biological activity was determined through DNA degradation and their cytotoxic effect on HeLa cells. The Cu/TiO2 nanoparticles presented a pore size between 2 and 6 nm, the size of nanoparticles agglomerates was between 100 and 500 nm. The nanoparticles of Cu/TiO2 degraded DNA starting at 15 min. The half maximal inhibitory concentration in HeLa cells depends on the used cooper complexes, the kinetics of cell death is of first order. Results revealed that these nanoparticles could be applied in uterine-cervical cancer treatment.
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- 2020
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46. The Effect of Lemon (Citrus limon) as a Coagulant on Fresh Cheese Chemical Composition And Storage
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Hamdan, T.H. Wahyuni, Muhammad Dila Wibowo, N. Ginting, and S.Sepriadi
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chemistry.chemical_compound ,Citrus limon ,Starter ,chemistry ,Chemical test ,Rennet ,Dry matter ,Food science ,Chemical composition ,Water content ,Completely randomized design ,Mathematics - Abstract
Demand for fresh cheese increases along with welfare. As Indonesia has a muslim population around 200 millions therefore there is a demand for halal cheese starter. The purpose of this research was to prove that the use of lemom juice as a replacement rennet is able to coagulate milk while produce fresh cheese which is also a halal because it comes from plants.This study aims to determine the lemon juice (citrus limon) in the process of milk coagulation. This research method used a 4 x 4 Factorial Completely Randomized Design with 2 replications of factor A, levels of lemon juice, namely A0 = 0.01% rennet, A1 = 5% lemon juice, A2 = 10% lemon juice, A3 = 15% lemon juice, and factor B storage time B0 = 0 days, B1 = 5 days, B2 = 10 days and B3 = 15 days. The variables measured were chemical compositions including moisture content, dry matter content, fat content, protein content. Based on the research results, it was found that from the addition of four levels of lemon juice used and four variations of storage time, giving 10% lemon juice (A2) and storage time of 15 days (B3) was the optimal treatment to increase moisture content, dry matter content, fat content, protein content in cheese and can be used as an alternative of halal cheese starter.
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- 2020
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47. Synergistic nano-tribological interaction between zinc dialkyldithiophosphate (ZDDP) and methyl oleate for biodiesel-fueled engines
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William Woei Fong Chong, Mei Bao Lee, Suhaila Mohd. Sanip, S. H. Hamdan, Cheng Tung Chong, and Chiew Tin Lee
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Biodiesel ,Materials science ,020209 energy ,Mechanical Engineering ,chemistry.chemical_element ,02 engineering and technology ,Activation energy ,Zinc ,Tribology ,Surfaces, Coatings and Films ,Dilution ,chemistry.chemical_compound ,020303 mechanical engineering & transports ,0203 mechanical engineering ,chemistry ,Chemical engineering ,Nano ,0202 electrical engineering, electronic engineering, information engineering ,Lubricant ,Fatty acid methyl ester - Abstract
In biodiesel-fueled compression-ignition (CI) engines, dilution by unburned biodiesel has been found to have adverse effects on the boundary lubrication properties of additives in fully formulated engine lubricants. Such dilution of engine lubricants could be even more pronounced for CI engines running on higher blend concentrations of biodiesel. Given the nanoscopic nature of the interaction, this study seeks to determine the nano-tribological properties of an engine lubricant additive (e.g., zinc dialkyldithiophosphate (ZDDP)) when diluted with a fatty acid methyl ester (e.g., methyl oleate). Using lateral force microscopy (LFM) together with a fluid imaging technique, the lowest nanoscopic friction forces and coefficient of friction values (0.068–0.085) were measured for ZDDP when diluted with 70 vol% of methyl oleate. These values are also observed to be lower than those measured for neat ZDDP and neat methyl oleate, respectively, under similar conditions. Subsequently, interpreting the data with the Eyring thermal activation energy approach, it could then be elucidated that the lower frictional losses observed for the contact lubricated with this volumetric mixture are a result of the lower potential energy barrier and activation energy required to initiate sliding. These energy values are approximated to be 2.6% and 28.9% (respectively) lower than that of the contact lubricated with neat ZDDP. It was also found that the mixture, at this volumetric concentration, possesses the highest possible pressure activation energy (load-carrying capacity) along with the lowest possible shear activation energy (shearing), potentially indicating optimum tribological conditions for boundary lubrication. Thus, the findings of this study suggest that an optimum concentration threshold exists in which a synergistic nano-tribological interaction between additives and fatty acid methyl esters can be attained, potentially reducing boundary frictional losses of lubricated conjunctions. Such findings could prove to be essential in effectively formulating synergistic additive concentrations for engine lubricants used in biodiesel-fueled CI engines.
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- 2020
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48. <scp>TSGIT</scp> : An N‐ and C‐terminal tandem tag system for purification of native and intein‐mediated ligation‐ready proteins
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Vlad-Stefan Raducanu, Masateru Takahashi, Yujing Ouyang, Samir M. Hamdan, Daniela-Violeta Raducanu, and Muhammad Tehseen
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Methods and Applications ,truncated protein ,Recombinant Fusion Proteins ,Intein ,Computational biology ,Protein degradation ,Cleavage (embryo) ,Biochemistry ,Inteins ,Bacteriophage ,03 medical and health sciences ,chemistry.chemical_compound ,protein ligation ,Biotin ,biotin ,protein cleavage ,Protein purification ,Cloning, Molecular ,protein expression ,Molecular Biology ,030304 developmental biology ,chemistry.chemical_classification ,0303 health sciences ,Expression vector ,biology ,fusion tag ,030302 biochemistry & molecular biology ,biology.organism_classification ,purification tag ,Amino acid ,chemistry ,SUMO ,protein degradation ,IPL - Abstract
A large variety of fusion tags have been developed to improve protein expression, solubilization, and purification. Nevertheless, these tags have been combined in a rather limited number of composite tags and usually these composite tags have been dictated by traditional commercially‐available expression vectors. Moreover, most commercially‐available expression vectors include either N‐ or C‐terminal fusion tags but not both. Here, we introduce TSGIT, a fusion‐tag system composed of both N‐ and a C‐terminal composite fusion tags. The system includes two affinity tags, two solubilization tags and two cleavable tags distributed at both termini of the protein of interest. Therefore, the N‐ and the C‐terminal composite fusion tags in TSGIT are fully orthogonal in terms of both affinity selection and cleavage. For using TSGIT, we streamlined the cloning, expression, and purification procedures. Each component tag is selected to maximize its benefits toward the final construct. By expressing and partially purifying the protein of interest between the components of the TSGIT fusion, the full‐length protein is selected over truncated forms, which has been a long‐standing problem in protein purification. Moreover, due to the nature of the cleavable tags in TSGIT, the protein of interest is obtained in its native form without any additional undesired N‐ or C‐terminal amino acids. Finally, the resulting purified protein is ready for efficient ligation with other proteins or peptides for downstream applications. We demonstrate the use of this system by purifying a large amount of native fluorescent mRuby3 protein and bacteriophage T7 gp2.5 ssDNA‐binding protein.
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- 2020
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49. Water vapour sorption behaviour and physico-mechanical properties of methyl methacrylate (MMA)- and MMA–styrene-modified batai (Paraserianthes falcataria) wood
- Author
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Hamdan Husain, Alia Syahirah Yusoh, Mohd Khairun Anwar Uyup, Siti Hanim Sahari, Seng Hua Lee, and Zaihan Jalaludin
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0106 biological sciences ,Moisture ,Chemistry ,Moisture sorption isotherm ,Sorption ,02 engineering and technology ,021001 nanoscience & nanotechnology ,01 natural sciences ,Equilibrium moisture content ,Styrene ,Biomaterials ,chemistry.chemical_compound ,010608 biotechnology ,Relative humidity ,Fourier transform infrared spectroscopy ,Methyl methacrylate ,0210 nano-technology ,Nuclear chemistry - Abstract
The purpose of this study was to determine the applicability of methyl methacrylate (MMA) and MMA–styrene in treating batai (Paraserianthes falcataria) wood. The effectiveness of the treatment was evaluated based on Fourier transform infrared spectroscopy (FTIR) analysis, physico-mechanical properties of the treated wood, and moisture sorption isotherm using dynamic vapour sorption (DVS) apparatus. Physico-mechanical properties of the modified batai wood were improved. The MMA-treated batai wood showed better improvement in terms of physical and mechanical properties compared to the MMA–styrene-treated batai wood. The equilibrium moisture content (EMC) for untreated batai wood was higher than that of treated samples. At 95% RH, the EMC for untreated batai wood was 20.7%, whereas the EMC for MMA- and MMA–styrene-treated samples was 7.9 and 8.8%, respectively. The findings indicate that the modified batai wood absorbed less moisture compared to the untreated batai wood. Moreover, the untreated batai wood had larger hysteresis loop than the treated batai wood. The highest hysteresis value was observed at 80% RH for untreated batai wood (3.8%), followed by MMA–styrene-treated batai wood (1.7%) and MMA-treated batai wood (1.2%). Both MMA and MMA–styrene proved to be effective treatments for batai wood because they reduced its hygroscopicity.
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- 2020
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50. IC50 Evaluation of Platinum Nanocatalysts for Cancer Treatment in Fibroblast, HeLa, and DU-145 Cell Lines
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Aida Hamdan-Partida, Marco A. González-López, Pamela G. González-Larraza, Francisco J. Padilla-Godínez, Esteban Gómez, and Tessy M. Lopez-Goerne
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biology ,business.industry ,General Chemical Engineering ,Cancer ,chemistry.chemical_element ,General Chemistry ,medicine.disease ,biology.organism_classification ,Article ,Nanomaterial-based catalyst ,HeLa ,Chemistry ,medicine.anatomical_structure ,chemistry ,Cell culture ,Cancer research ,Medicine ,Nanomedicine ,business ,Platinum ,Fibroblast ,QD1-999 ,IC50 - Abstract
Cancer is a major public health problem being one of the main causes of morbidity and mortality today. Recent advances in catalytic nanomedicine have offered new cancer therapies based on the administration of nanoparticles (NPs) of platinum (Pt) dispersed in catalytic mesoporous nanomaterials (titania, TiO2) with highly selective cytotoxic properties and no adverse effects. A half maximal inhibitory concentration (IC50) study was carried out in cancerous cell lines (HeLa, DU-145, and fibroblasts) to evaluate the cytotoxic effect of different nanomaterials [Pt/TiO2, TiO2, and Pt(acac)2] synthesized by the sol–gel method at concentrations 0–1000 μg/mL. The assays showed that IC50 values for Pt in functionalized TiO2 (NPt) in HeLa (53.74 ± 2.95 μg/mL) and DU-145 (75.07 ± 5.48 μg/mL) were lower than those of pure TiO2 (74.29 ± 8.95 and 82.02 ± 6.03 μg/mL, respectively). Pt(acac)2 exhibited no cytotoxicity. Normal cells (fibroblasts) treated with NPt exhibited no significant growth inhibition, suggesting the high selectivity of the compound for cancerous cells only. TiO2 and NPt were identified as antineoplastic compounds in vitro. Pt(acac)2 is not recommendable because of the low cytotoxicity observed.
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- 2020
- Full Text
- View/download PDF
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