44 results on '"In-vitro assay"'
Search Results
2. Phytochemical composition, antioxidant and antibacterial properties of methanol stem and leaf extracts of Croton bonplandianus Baill
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Kumar, Indrajeet, Kumar, Umesh, Singh, Prince Kumar, Yadav, Jay Shankar, Dwivedi, Akanksha, Singh, Priyanka, Tripathi, Ashutosh, and Sharma, Rajesh Kumar
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- 2024
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3. Identification of new pharmacophore against SARS-CoV-2 spike protein by multi-fold computational and biochemical techniques
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Atta Ullah, Saeed Ullah, Sobia Ahsan Halim, Muhammad Waqas, Basharat Ali, Farid S. Ataya, Nasser M. El-Sabbagh, Gaber El-Saber Batiha, Satya Kumar Avula, Rene Csuk, Ajmal Khan, and Ahmed Al-Harrasi
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SARS CoV-2 ,Spike protein ,Molecular docking ,In-vitro assay ,Boswellic acid ,Medicine ,Science - Abstract
Abstract COVID-19 appeared as a highly contagious disease after its outbreak in December 2019 by the virus, named SARS-CoV-2. The threat, which originated in Wuhan, China, swiftly became an international emergency. Among different genomic products, spike protein of virus plays a crucial role in the initiation of the infection by binding to the human lung cells, therefore, SARS-CoV-2’s spike protein is a promising therapeutic target. Using a combination of a structure-based virtual screening and biochemical assay, this study seeks possible therapeutic candidates that specifically target the viral spike protein. A database of ~ 850 naturally derived compounds was screened against SARS-CoV-2 spike protein to find natural inhibitors. Using virtual screening and inhibitory experiments, we identified acetyl 11-keto-boswellic acid (AKBA) as a promising molecule for spike protein, which encouraged us to scan the rest of AKBA derivatives in our in-house database via 2D-similarity searching. Later 19 compounds with > 85% similarity with AKBA were selected and docked with receptor binding domain (RBD) of spike protein. Those hits declared significant interactions at the RBD interface, best possess and excellent drug-likeness and pharmacokinetics properties with high gastrointestinal absorption (GIA) without toxicity and allergenicity. Our in-silico observations were eventually validated by in vitro bioassay, interestingly, 10 compounds (A3, A4, C3, C6A, C6B, C6C, C6E, C6H, C6I, and C6J) displayed significant inhibitory ability with good percent inhibition (range: > 72–90). The compounds C3 (90.00%), C6E (91.00%), C6C (87.20%), and C6D (86.23%) demonstrated excellent anti-SARS CoV-2 spike protein activities. The docking interaction of high percent inhibition of inhibitor compounds C3 and C6E was confirmed by MD Simulation. In the molecular dynamics simulation, we observed the stable dynamics of spike protein inhibitor complexes and the influence of inhibitor binding on the protein’s conformational arrangements. The binding free energy ΔGTOTAL of C3 (−38.0 ± 0.08 kcal/mol) and C6E (−41.98 ± 0.08 kcal/mol) respectively indicate a strong binding affinity to Spike protein active pocket. These findings demonstrate that these molecules particularly inhibit the function of spike protein and, therefore have the potential to be evaluated as drug candidates against SARS-CoV-2.
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- 2024
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4. Cytotoxic Profiling of the Marine Gastropod (Conus textile) Venom Extracts on Human Cancer Cell Lines Unveiling its Therapeutic Side as Anti-Cancer Therapeutic Agents.
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Abdella, Mohamed H., Azab, Ahmad M., El-Naggar, Hussien A., and Abed Elrheem, Ali A.
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VENOM , *CELL lines , *CONUS , *CANCER cells , *ANTINEOPLASTIC agents , *MARINE natural products - Abstract
Conus marine snails can be identified by their venom compositions, which are complex and comprise a wide variety of pharmacologically potent peptides known as conotoxins. Due to their possible therapeutic usages, these peptides have attracted a lot of attention, especially in the field of oncology. This work aimed to study the cytotoxic effects of venom gland and venom tube extracts from Conus textile on three human cancer cell lines (namely HepG2, hepatocellular carcinoma, Caco2, colorectal cancer, Mcf7, and breast cancer). The present study assessed the venoms' half-maximal inhibitory concentrations (IC50), which represented their effectiveness in lowering cell viability, using an in-vitro experiment. With IC50 values ranging between 94 and 381.97µg/ml, the results showed that both venom extracts had strong cytotoxic effects on all examined cell lines. When compared to the gland extract, the venom tube extract consistently showed greater potency, which may indicate a higher concentration of active cytotoxic chemicals. When treated with venom tube extract, the Mcf7 cell line showed the lowest IC50 value, suggesting a promising potential for breast cancer therapies. These findings supported the hypothesis that Conus textile venom contains bioactive components with selective toxicity towards cancer cell lines. The insignificant standard deviations reported support the regularity and dependability of the cytotoxic effects. The present work provided the foundation for future purifying and mechanistic investigations of conotoxins and advanced the investigation of marine natural products as a source of potential anti-cancer drugs. [ABSTRACT FROM AUTHOR]
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- 2024
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5. Inhibition of Uridine 5′-diphospho-glucuronosyltransferases A10 and B7 by vitamins: insights from in silico and in vitro studies.
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Pande, Sonal, Patel, Chirag A., Dhameliya, Tejas M., Beladiya, Jayesh, Parikh, Palak, Kachhadiya, Radhika, and Dholakia, Sandip
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URIDINE , *VITAMINS , *IN vitro studies , *VITAMIN B1 , *DRUG metabolism , *INDIVIDUALIZED medicine , *METABOLIC detoxification , *VITAMIN A - Abstract
Uridine 5′-diphospho-glucuronosyltransferases (UGTs) have been considered as a family of enzymes responsible for the glucuronidation process, a crucial phase II detoxification reaction. Among the various UGT isoforms, UGTs A10 and B7 have garnered significant attention due to their broad substrate specificity and involvement in the metabolism of numerous compounds. Recent studies have suggested that certain vitamins may exert inhibitory effects on UGT activity, thereby influencing the metabolism of drugs, environmental toxins, and endogenous substances, ultimately impacting their biological activities. In the present study, the inhibition potential of vitamins (A, B1, B2, B3, B5, B6, B7, B9, D3, E, and C) on UGT1A10 and UGT2B7 was determined using in silico and in vitro approaches. A 3-dimensional model of UGT1A10 and UGT2B7 enzymes was built using Swiss Model, ITASSER, and ROSETTA and verified using Ramachandran plot and SAVES tools. Molecular docking studies revealed that vitamins interact with UGT1A10 and UGT2B7 enzymes by binding within the active site pocket and interacting with residues. Among all vitamins, the highest binding affinity predicted by molecular docking was − 8.61 kcal/mol with vitamin B1. The in vitro studies results demonstrated the inhibition of the glucuronidation activity of UGTs by vitamins A, B1, B2, B6, B9, C, D, and E, with IC50 values of 3.28 ± 1.07 µg/mL, 24.21 ± 1.11 µg/mL, 3.69 ± 1.02 µg/mL, 23.60 ± 1.08 µg/mL, 6.77 ± 1.08 µg/mL, 83.95 ± 1.09 µg/ml, 3.27 ± 1.13 µg/mL and 3.89 ± 1.12 µg/mL, respectively. These studies provided the valuable insights into the mechanisms underlying drug-vitamins interactions and have the potential to guide personalized medicine approaches, optimizing therapeutic outcomes, and ensuring patient safety. Indeed, further research in the area of UGT (UDP-glucuronosyltransferase) inhibition by vitamins is essential to fully understand the clinical relevance and implications of these interactions. UGTs play a crucial role in the metabolism and elimination of various drugs, toxins, and endogenous compounds in the body. Therefore, any factors that can modulate UGT activity, including vitamins, can have implications for drug metabolism, drug-drug interactions, and overall health. [ABSTRACT FROM AUTHOR]
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- 2024
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6. Immobilization of cytochrome P450 enzymes onto magnetic beads: An approach to drug metabolism and biocatalysis
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Izadora Liranço Furlani, Regina Vincenzi Oliveira, and Quezia Bezerra Cass
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CYP450 immobilization ,Drug metabolism ,Biocatalysts ,Phenotyping ,In-vitro assay ,Analytical chemistry ,QD71-142 - Abstract
Cytochrome P450 (CYP, P450) presents a wide range of applicability in drug metabolism studies and in biocatalysis as a great alternative to synthesizing compounds. Nonetheless, their lack of stability is one of their major drawbacks. Aiming the possibility of enhancing the catalytic activity and promoting higher stability, liver microsomal fractions have been immobilized on magnetic beads (Mb). The immobilized procedure was modulated by using rat liver microsomal fractions (RLM-Mb). The optimal condition achieved was further employed for the immobilization of the human microsomal fractions on magnetic beads (HLM-Mb). In vitro metabolism assays were conducted using albendazole (ABZ) as a model drug, and the formation of albendazole sulfoxide (ABZSO) was monitored. Biotransformation reactions applying the produced HLM-Mb were examined for the best temperature to increase the production of metabolites and their reuse cycles. A kinetic study was carried out for HLM-Mbs monitoring the production of ABZO by the oxidation reaction of ABZ by CYP3A4. The Km value was 25.6 µmol L−1 and Vmax was 121.0 µmol L−1. Inhibition assays were conducted in the presence of ketoconazole and the production of ABZSO decreased by 46.8 ± 2.5%. Enzymatic activities for CYP2C9 and CYP2D6 on HLM-Mbs were evaluated by monitoring the hydroxylation reactions of diclofenac and bufuralol as substrates. The immobilization of CYP P450 on magnetic beads increased not only the production of ABZSO metabolites but also the stability of CYP. The use of HLM-Mbs jointly with immobilized glucose-6-phosphate dehydrogenase (G6PDH-Mbs) as a unique dual generator system to produce NADPH has established the one-pot conditions for biocatalysis in a greener approach with reuse of the biocatalyst (G6PDH-HLM-Mbs). To this end, the herein reported HLM-Mbs and G6PDH-HLM-Mbs are excellent analytical tools to be explored either in biocatalysis reactions or in in vitro metabolism studies.
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- 2023
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7. Standardized in-vitro evaluation of CAR-T cells using acellular artificial target particles.
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Harari-Steinfeld, Rona, Ayyadevara, V. S. S. Abhinav, Cuevas, Lizette, Marincola, Francesco, and Kyung-Ho Roh
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CELL surface antigens ,TUMOR antigens ,MANUFACTURING cells ,IMMUNE response ,GOVERNMENT agencies - Abstract
The horizon of immunotherapy using CAR-T cells is continuously extending to treat solid tumors beyond the success in the treatment of liquid tumors. Precise in-vitro evaluations of CAR-T cells for their phenotypes, quantity and quality of activation in various tumor microenvironments including different antigen densities, and the resulting effector functions are critical for the successful development of CAR-T therapies and safe translation to clinics. Unfortunately, the development of methods and tools to accommodate these needs have been lagging behind. Here, we developed a novel biomaterial platform, acellular artificial target particles (aaTPs) against CAR-T cells, using magnetic microbeads that are already widely employed in the manufacturing of T cell products. By devising a simple and standardized procedure, we precisely controlled the antigen surface densities presented on the aaTPs for a wide range. By co-incubation of aaTPs with CAR-T cells followed by flow cytometry and cytokine assays, we quantitatively determined the antigen-specific and dose-dependent activation of anti-HER2 CAR-T cells. We also demonstrated that the aaTP can serve as a clean target cell in in-vitro assays to prove the proposed mechanism of action of a next-generation CAR-T product. Overall, the simple, inexpensive, modular and precisely controllable synthetic nature of aaTPs enables the development of clean and standardized in-vitro assays for CAR-T cells, which provides critical advantages over the conventional assays using target cell lines. The design of aaTPs can be extended to include other tumor antigens and relevant surface molecules of physiological target cells. Thus, the aaTP platform has great potential as a standardized tool for the development and evaluation of both conventional and new CAR-T products in the context of approval from regulatory agencies and clinical translation. [ABSTRACT FROM AUTHOR]
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- 2022
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8. Standardized in-vitro evaluation of CAR-T cells using acellular artificial target particles
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Rona Harari-Steinfeld, V. S. S. Abhinav Ayyadevara, Lizette Cuevas, Francesco Marincola, and Kyung-Ho Roh
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CAR-T ,in-vitro assay ,potency assay ,acellular ,biomaterials ,artificial ,Immunologic diseases. Allergy ,RC581-607 - Abstract
The horizon of immunotherapy using CAR-T cells is continuously extending to treat solid tumors beyond the success in the treatment of liquid tumors. Precise in-vitro evaluations of CAR-T cells for their phenotypes, quantity and quality of activation in various tumor microenvironments including different antigen densities, and the resulting effector functions are critical for the successful development of CAR-T therapies and safe translation to clinics. Unfortunately, the development of methods and tools to accommodate these needs have been lagging behind. Here, we developed a novel biomaterial platform, acellular artificial target particles (aaTPs) against CAR-T cells, using magnetic microbeads that are already widely employed in the manufacturing of T cell products. By devising a simple and standardized procedure, we precisely controlled the antigen surface densities presented on the aaTPs for a wide range. By co-incubation of aaTPs with CAR-T cells followed by flow cytometry and cytokine assays, we quantitatively determined the antigen-specific and dose-dependent activation of anti-HER2 CAR-T cells. We also demonstrated that the aaTP can serve as a clean target cell in in-vitro assays to prove the proposed mechanism of action of a next-generation CAR-T product. Overall, the simple, inexpensive, modular and precisely controllable synthetic nature of aaTPs enables the development of clean and standardized in-vitro assays for CAR-T cells, which provides critical advantages over the conventional assays using target cell lines. The design of aaTPs can be extended to include other tumor antigens and relevant surface molecules of physiological target cells. Thus, the aaTP platform has great potential as a standardized tool for the development and evaluation of both conventional and new CAR-T products in the context of approval from regulatory agencies and clinical translation.
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- 2022
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9. Bioaccessibility of iron in developed pectin iron complex using Citrus limon Burm F. peels subjected to in-vitro gastro-pancreatic digestion.
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Singhal, Somya, Swami Hulle, Nishant Rachayya, and Koidis, Anastasios
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LEMON , *FERRIC chloride , *IRON deficiency , *FOOD industry , *WORLD health , *PECTINS - Abstract
Pectin from the citrus peel waste has novel applications in food and biomedical industries. The present work focused on addressing iron deficiency, which is a global health concern, by developing a functional ingredient using pectin extracted from Assam lemon (Citrus limon Burm. F) and supplementing iron via the pectin‑iron complex (PIC). Extracted pectin was incubated with iron chloride hexahydrate (0.90–1.80 mM) for 180 h to optimize the complexation conditions, with the optimal concentration being 1.36 mM. The iron bioavailability and its absorption in the PIC was assessed using in-vitro simulation digestion and Caco-2 cell monolayers. The bioaccessible form of iron in the developed PIC during the intestinal phase was 5.34 ± 0.16%, which was negligible in pectin. The absorption of bioaccessible iron in the PIC was found to be 2.93 ± 0.03%. The results demonstrated that PIC could reduce iron deficiency and increase fibre intake, leading to several health benefits. [Display omitted] • Pectin-iron complex was in-vitro digested and introduced to Caco-2 monolayers. • PIC and pectin exhibited DE > 50% extending their application in the food system. • PIC exhibited stability under a simulated in vitro digestion system. [ABSTRACT FROM AUTHOR]
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- 2024
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10. Pharmacological Characterization of Daboia russelii Venom and its Neutralization by Polyvalent Chicken Antibodies.
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GRACE, S. PRIYA and KUMAR, A. GANESH
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Snake bite is considered as a socio-economic problem in tropical countries. Daboia russelii (Russell's viper) is responsible for 30-40% of all snakebites and the most number of life-threatening bites. Antivenom is the only treatment available. Hyperimmune sera raised from horses were shown to produce adverse effects. In this study, chicken Ig Y was generated against the venom of D. russelii and its neutralization studies were carried out by invitro methods. Antivenom antibodies were generated in chicken and purified by DEAE cellulose column and the antibody titre was estimated in serum and egg yolk by ELISA which showed the increase in titres. Ig Y was subjected to protein estimation, and SDS-PAGE was carried out to study the banding pattern. High molecular weight band 180 KD was observed. Pharmacological characterization like coagulant activity, direct haemolytic assay, indirect haemolytic assay and proteolytic activity was carried out. Minimum coagulant dose was found to be 120 µg. Neutralization studies were carried out using column purified Ig Y antibodies. Current study suggests that Ig Y antivenoms are effective in neutralising the pharmacological activities induced by venom. [ABSTRACT FROM AUTHOR]
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- 2022
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11. Review of Current COVID-19 Diagnostics and Opportunities for Further Development
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Yan Mardian, Herman Kosasih, Muhammad Karyana, Aaron Neal, and Chuen-Yen Lau
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COVID-19 ,diagnostics ,clinical ,in-vitro assay ,molecular test ,serologic test ,Medicine (General) ,R5-920 - Abstract
Diagnostic testing plays a critical role in addressing the coronavirus disease 2019 (COVID-19) pandemic, caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). Rapid and accurate diagnostic tests are imperative for identifying and managing infected individuals, contact tracing, epidemiologic characterization, and public health decision making. Laboratory testing may be performed based on symptomatic presentation or for screening of asymptomatic people. Confirmation of SARS-CoV-2 infection is typically by nucleic acid amplification tests (NAAT), which requires specialized equipment and training and may be particularly challenging in resource-limited settings. NAAT may give false-negative results due to timing of sample collection relative to infection, improper sampling of respiratory specimens, inadequate preservation of samples, and technical limitations; false-positives may occur due to technical errors, particularly contamination during the manual real-time polymerase chain reaction (RT-PCR) process. Thus, clinical presentation, contact history and contemporary phyloepidemiology must be considered when interpreting results. Several sample-to-answer platforms, including high-throughput systems and Point of Care (PoC) assays, have been developed to increase testing capacity and decrease technical errors. Alternatives to RT-PCR assay, such as other RNA detection methods and antigen tests may be appropriate for certain situations, such as resource-limited settings. While sequencing is important to monitor on-going evolution of the SARS-CoV-2 genome, antibody assays are useful for epidemiologic purposes. The ever-expanding assortment of tests, with varying clinical utility, performance requirements, and limitations, merits comparative evaluation. We herein provide a comprehensive review of currently available COVID-19 diagnostics, exploring their pros and cons as well as appropriate indications. Strategies to further optimize safety, speed, and ease of SARS-CoV-2 testing without compromising accuracy are suggested. Access to scalable diagnostic tools and continued technologic advances, including machine learning and smartphone integration, will facilitate control of the current pandemic as well as preparedness for the next one.
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- 2021
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12. Impaired in vitro growth response of plasma-treated cardiomyocytes predicts poor outcome in patients with transthyretin amyloidosis.
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Hein, Selina, Furkel, Jennifer, Knoll, Maximilian, aus dem Siepen, Fabian, Schönland, Stefan, Hegenbart, Ute, Katus, Hugo A., Kristen, Arnt V., and Konstandin, Mathias H.
- Abstract
Objectives: Direct toxic effects of transthyretin amyloid in patient plasma upon cardiomyocytes are discussed. However, no data regarding the relevance of this putative effect for clinical outcome are available. In this monocentric prospective study, we analyzed cellular hypertrophy after phenylephrine stimulation in vitro in the presence of patient plasma and correlated the cellular growth response with phenotype and prognosis. Methods and results: Progress in automated microscopy and image analysis allows high-throughput analysis of cell morphology. Using the InCell microscopy system, changes in cardiomyocyte's size after treatment with patient plasma from 89 patients suffering from transthyretin amyloidosis and 16 controls were quantified. For this purpose, we propose a novel metric that we named Hypertrophic Index, defined as difference in cell size after phenylephrine stimulation normalized to the unstimulated cell size. Its prognostic value was assessed for multiple endpoints (HTX: death/heart transplantation; DMP: cardiac decompensation; MACE: combined) using Cox proportional hazard models. Cells treated with plasma from healthy controls and hereditary transthyretin amyloidosis with polyneuropathy showed an increase in Hypertrophic Index after phenylephrine stimulation, whereas stimulation after treatment with hereditary cardiac amyloidosis or wild-type transthyretin patient plasma showed a significantly attenuated response. Hypertrophic Index was associated in univariate analyses with HTX (hazard ratio (HR) high vs low: 0.12 [0.02–0.58], p = 0.004), DMP: (HR 0.26 [0.11–0.62], p = 0.003) and MACE (HR 0.24 [0.11–0.55], p < 0.001). Its prognostic value was independent of established risk factors, cardiac TroponinT or N-terminal prohormone brain natriuretic peptide (NTproBNP). Conclusions: Attenuated cardiomyocyte growth response after stimulation with patient plasma in vitro is an independent risk factor for adverse cardiac events in ATTR patients [ABSTRACT FROM AUTHOR]
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- 2021
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13. Interferon-Gamma, a valuable surrogate marker of Plasmodium falciparum pre-erythrocytic stages protective immunity
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Perlaza, Blanca-Liliana, Sauzet, Jean-Pierre, Brahimi, Karima, BenMohamed, Lbachir, and Druilhe, Pierre
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malaria vaccine development ,x-irradiated sporozoites ,t-lymphocyte responses ,in-vitro assay ,circumsporozoite protein ,inhibitory-activity ,liver stages ,exoerythrocytic stages ,effector mechanisms ,synthetic peptides - Abstract
Immunity against the pre-erythrocytic stages of malaria is the most promising, as it is strong and fully sterilizing. Yet, the underlying immune effectors against the human Plasmodium falciparum pre-erythrocytic stages remain surprisingly poorly known and have been little explored, which in turn prevents any rational vaccine progress. Evidence that has been gathered in vitro and in vivo, in higher primates and in humans, is reviewed here, emphasizing the significant role of IFN-gamma, either as a critical immune mediator or at least as a valuable surrogate marker of protection. One may hope that these results will trigger investigations in volunteers immunized either by optimally irradiated or over-irradiated sporozoites, to quickly delineate better surrogates of protection, which are essential for the development of a successful malaria vaccine.
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- 2011
14. Design, synthesis, and evaluation of novel cinnamic acid-tryptamine hybrid for inhibition of acetylcholinesterase and butyrylcholinesterase.
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Ghafary, Shahrzad, Ghobadian, Roshanak, Mahdavi, Mohammad, Nadri, Hamid, Moradi, Alireza, Akbarzadeh, Tahmineh, Najafi, Zahra, Sharifzadeh, Mohammad, Edraki, Najmeh, Moghadam, Farshad Homayouni, and Amini, Mohsen
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ACETYLCHOLINESTERASE , *CHOLINESTERASE inhibitors , *CARBOCYCLIC acids - Abstract
Background: Acetylcholine deficiencies in hippocampus and cortex, aggregation of β-amyloid, and β-secretase over activity have been introduced as main reasons in pathogenesis of Alzheimer's disease. Methods: Colorimetric Ellman's method was used for determination of IC50 value in AChE and BChE inhibitory activity. The kinetic studies, neuroprotective and β-secretase inhibitory activities, evaluation of inhibitory potency on β-amyloid (Aβ) aggregations induced by AChE, and docking study were performed for prediction of the mechanism of action. Result and discussion: A new series of cinnamic acids-tryptamine hybrid was designed, synthesized, and evaluated as dual cholinesterase inhibitors. These compounds demonstrated in-vitro inhibitory activities against acetyl cholinesterase (AChE) and butyryl cholinesterase (BChE). Among of these synthesized compounds, (E)-N-(2-(1H-indol-3-yl)ethyl)-3-(3,4-dimethoxyphenyl)acrylamide (5q) demonstrated the most potent AChE inhibitory activity (IC50 = 11.51 μM) and (E)-N-(2-(1H-indol-3-yl)ethyl)-3-(2-chlorophenyl)acrylamide (5b) were the best anti-BChE (IC50 = 1.95 μM) compounds. In addition, the molecular modeling and kinetic studies depicted 5q and 5b were mixed type inhibitor and bound with both the peripheral anionic site (PAS) and catalytic sites (CAS) of AChE and BChE. Moreover, compound 5q showed mild neuroprotective in PC12 cell line and weak β-secretase inhibitory activities. This compound also inhibited aggregation of β-amyloid (Aβ) in self-induced peptide aggregation test at concentration of 10 μM. Conclusion: It is worth noting that both the kinetic study and the molecular modeling of 5q and 5b depicted that these compounds simultaneously interacted with both the catalytic active site and the peripheral anionic site of AChE and BChE. These findings match with those resulted data from the enzyme inhibition assay. [ABSTRACT FROM AUTHOR]
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- 2020
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15. Eco-friendly bio-larvicidal and antimicrobial activity of isolated bioactive compound from Kurthia gibsonii (Bacillales).
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Arul D, Vinoth G, Muthusamy R, Natarajan T, Kamaraj C, Deepak P, Dhanasundaramd S, Perumal P, and Ramkumar G
- Abstract
The targeted organisms include mosquito vectors, bacterial pathogens and non-targeted organisms. Preliminary mosquito larvicidal activity was conducted using cell-free supernatants (CFSs) from 11 gut bacteria. Among them, the bacterium SS11 exhibited promising results and was identified as Kurthia gibsonii based on its 16S rRNA sequence (1350 bp). The diethyl ether extract (DEE) of K. gibsonii demonstrated significant larvicidal effects, with LC50 values of 5.59 µL/mL and 8.59 µL/mL for 3rd instar larvae of Aedes aegypti and 2nd instar larvae of Anopheles stephensi , respectively. Analysis of the DEE using FT-IR, and GC-MS revealed the presence of 16 functional groups, and 7 bioactive compounds, respectively. A molecular docking study identified GC-MS compounds against odorant receptors from A. aegypti and odorant-binding proteins from A. stephensi was performed to assess the interaction and binding affinity. Overall, these findings suggest that the bioactive compounds 2, 4, 6-tribromoaniline from the DEE of K. gibsonii hold potential as an environmentally compatible alternative for biocontrol purposes, and compounds 9-tricosene and didecyl phthalate can be used for mosquito traps.
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- 2024
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16. Nitric oxide triggered defense network in wheat: Augmenting tolerance and grain-quality related traits under heat-induced oxidative damage.
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Kumar, R.R., Tasleem, M., Jain, M., Ahuja, S., Goswami, S., Bakshi, S., Jambhulkar, S., Singh, S.D., Singh, G.P., Pathak, H., Viswanathan, C., and Praveen, S.
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WHEAT quality , *PHYSIOLOGICAL effects of nitric oxide , *EFFECT of heat on plants , *PHYSIOLOGICAL effects of heat , *OXIDATIVE stress - Abstract
Highlights • The effect of heat stress can be alleviated by nitric oxide (150 μM) treatment in wheat. • Nitric oxide triggers the expression of SAGs and enhances the scavenging potential of wheat under heat stress. • Nitric oxide improves the quality of wheat grain by enhancing the accumulation of gliadin protein and starch. • Nitric oxide maintains the quality of starch in wheat grain by reducing the amylolytic activity under heat stress. • Nitric oxide enhances the accumulation of soluble protein, free amino acids and osmolyte in developing grains under HS. Abstract Heat stress (HS) drastically reduces the yield and quality of wheat grains. High temperature during critical stages (pollination and grain-filling) causes improper fertilization and formation of defragmented granules and shriveled seeds. Hormones and signaling molecules modulates the tolerance potential of the plants under stress. Nitric oxide (NO) is an important signaling molecule involved in triggering diverse physiological and biochemical processes under adverse conditions. Here, we studied the effect of sodium nitroprusside (SNP) (150 μM set based on pilot experiment) on heat stress-tolerance and grain quality related traits of two contrasting wheat cultivars Raj3765 as thermotolerant and HD2932 as thermosusceptible under differential HS (T 1 - 30 °C, 1 h; T 2 - 38 °C, 1 h), as compared to control (22 ± 2 °C) at different stages of growth. The expression of many important stress-associated genes (previously identified through Transcriptome sequencing) was observed upregulated in response to NO and HS; small HSP17 showed maximum fold increase in Raj3765. Similarly, the networks of antioxidant enzymes (SOD, CAT, and GPX) were observed triggered in response to NO, HS and NO + HS treatment in Raj3765 than HD2932. The accumulation of proline and free amino acid in cytoplasm were also reported higher under NO and HS treatment respectively in Raj3765, as compared to HD2932. Grain quality related traits like carbohydrate (starch) and proteins (gliadin) were observed higher in response to NO under HS in Raj3765. Heat stress was observed to increase the activities of α/β amylases in developing grains involved in degrading the starch quality. NO was observed to decrease the amylolytic activity in both the cultivars; very low amylolytic activity was observed in thermotolerant, as compared to thermosusceptible cultivars. Exogenous application of NO (150 μM) at different stages can be used as inexpensive technology for mitigating the problem of terminal HS in wheat – a farmer friendly approach for maintaining the quality of grains under present threat of global climate change. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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17. Flow-through dynamic microextraction system for automatic in vitro assessment of chyme bioaccessibility in food commodities.
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Souza, Lais A., Rosende, María, Korn, Maria Graças A., and Miró, Manuel
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EXTRACTION (Chemistry) , *CHYME , *GASTROINTESTINAL system , *MICRONUTRIENTS , *OPTICAL spectrometers - Abstract
An automatic flow-through dynamic extraction method is proposed for the first time for in vitro exploration, with high temporal resolution, of the transit of the chyme from the gastric to the duodenal compartment using the Versantvoort's fed-state physiologically relevant extraction test. The flow manifold was coupled on-line to an inductively coupled plasma optical emission spectrometer (ICP OES) for real-time elucidation of the bioaccessible elemental fraction of micronutrients (viz., Cu, Fe and Mn) in food commodities across the gastrointestinal tract. The simulated intestinal and bile biofluid (added to the gastric phase) was successively pumped at 1.0 mL min −1 through a large-bore column (maintained at 37.0 ± 2.0 °C) initially loaded with a weighed amount of linseed (250 mg) using a PVDF filter membrane (5.0 μm pore size) for retaining of the solid sample and in-line filtration of the extracts. The lack of bias (trueness) of the on-line gastrointestinal extraction method coupled to ICP OES was confirmed using mass balance validation following microwave assisted digestion of the residual (non-bioaccessible) elemental fraction. Mass balance validation yielded absolute recoveries spanning from 79 to 121% for the overall analytes and samples. On-line dynamic extraction was critically appraised against batch counterparts for both gastric and gastrointestinal compartments. Due to the lack of consensus in the literature regarding the agitation method for batch oral bioaccessibility testing, several extraction approaches (viz., magnetic stirring, end-over-end rotation and orbital shaking) were evaluated. Improved gastric extractability of Fe along with bioaccessible data comparable to the dynamic counterpart based on the continuous displacement of the extraction equilibrium was obtained with batchwise magnetic stirring, which is deemed most appropriate for ascertaining worst-case/maximum bioaccessibility scenarios. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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18. Novel tetrahydrocarbazole benzyl pyridine hybrids as potent and selective butryl cholinesterase inhibitors with neuroprotective and β-secretase inhibition activities.
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Ghobadian, Roshanak, Mahdavi, Mohammad, Nadri, Hamid, Moradi, Alireza, Edraki, Najmeh, Akbarzadeh, Tahmineh, Sharifzadeh, Mohammad, Bukhari, Syed Nasir Abbas, and Amini, Mohsen
- Subjects
- *
CHOLINESTERASE inhibitors , *ENZYME inhibitors , *CHOLINESTERASE reactivators , *NEUROPROTECTIVE agents , *BUTYRYLCHOLINESTERASE , *ALZHEIMER'S disease - Abstract
Butyrylcholinesterase (BuChE) inhibitors have become interesting target for treatment of Alzheimer's disease (AD). A series of dual binding site BuChE inhibitors were designed and synthesized based on 2,3,4,9-tetrahydro-1H-carbazole attached benzyl pyridine moieties. In-vitro assay revealed that all of the designed compounds were selective and potent BuChE inhibitors. The most potent BuChE inhibitor was compound 6i (IC 50 = 0.088 ± 0.0009 μM) with the mixed-type inhibition. Docking study revealed that 6i is a dual binding site BuChE inhibitor. Also, Pharmacokinetic properties for 6i were accurate to Lipinski's rule. In addition, compound 6i demonstrated neuroprotective and β-secretase (BACE1) inhibition activities. This compound could also inhibit AChE-induced and self-induced Aβ peptide aggregation at concentration of 100 μM and 10 μM respectively. Generally, the results are presented as new potent selective BuChE inhibitors with a therapeutic potential for the treatment of AD. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
19. In vitro ovicidal and larvicidal activity of Butea frondosa (Palas) seeds extract on Haemonchus contortus
- Author
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Swarnkar, C.P., Singh, D., Khan, F.A., Kumar, M., Bhagwan, P.S.K., and Dubey, S.C.
- Published
- 2008
20. On-line coupling of physiologically relevant bioaccessibility testing to inductively coupled plasma spectrometry: Proof of concept for fast assessment of gastrointestinal bioaccessibility of micronutrients from soybeans.
- Author
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Herrera, Mónica Alejandra, Rosende, María, Arruda, Marco Aurélio Zezzi, and Miró, Manuel
- Subjects
- *
INDUCTIVELY coupled plasma mass spectrometry , *GASTROINTESTINAL agents , *MICRONUTRIENTS , *SOYBEAN , *BIOAVAILABILITY - Abstract
In-vitro physiologically relevant gastrointestinal extraction based on the validated Unified BARGE Method (UBM) is in this work hyphenated to inductively coupled plasma optical emission spectrometry in a batch-flow configuration for real-time monitoring of oral bioaccessibility assays with high temporal resolution. A fully automated flow analyzer is designed to foster in-line filtration of gastrointestinal extracts at predefined times (≤15 min) followed by on-line multi-elemental analysis of bioaccessible micro-nutrients, viz ., Cu, Fe and Mn, in well-defined volumes of extracts (300 μL) of transgenic and non-transgenic soybean seeds taken as model samples. The hyphenated flow setup allows for recording of temporal extraction profiles to gain full knowledge of the kinetics of the gastrointestinal digestion processes, including element leaching and concomitant precipitation and complexation reactions hindering bioavailability. Simplification of the overall standard procedure is also feasible by identification of steady-state extraction conditions. Our findings indicate that reliable measurement of oral bioaccessible pools of Cu, Fe and Mn in soybean might be obtained in less than 180 min rather than 240 min as endorsed by UBM. Using a matrix-matched external calibration, limits of detection according to the 3s criteria were 0.5 μg/g for Mn, 0.6 μg/g for Cu and 2.3 μg/g for Fe. Trueness of the automatic bioaccessibility method was confirmed by mass balance validation with recoveries ranging from 87 to 116% regardless of the target element and sample. Cu was the micronutrient with the highest oral bioaccessibility ranging from 73% to 83% (7.5–7.9 μg/g) for non-transgenic and transgenic soybeans, respectively, followed by Mn and Fe within the ranges of 29–31% (10.8–11.4 μg/g) and 11–15% (8–14 μg/g), respectively, regardless of transgenesis. The proposed kinetic method is proven suitable for fast and expedient estimation of the nutritional value of soybeans and elucidation of the potential effect of transgenesis onto bioaccessible fractions of elements. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
21. Sensitive detection of antigen-specific T-cells using bead-bound antigen for in vitro re-stimulation
- Author
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Guro Gafvelin, Sabrina Ruhrmann, Mattias Bronge, Claudia Carvalho-Queiroz, Erik Holmgren, Andreas Kaiser, Ola Nilsson, Tomas Olsson, and Hans Grönlund
- Subjects
T cell ,Clinical Biochemistry ,010501 environmental sciences ,Microparticles ,01 natural sciences ,Peripheral blood mononuclear cell ,03 medical and health sciences ,Antigen ,T-cell ,medicine ,lcsh:Science ,Antigen-presenting cell ,In-vitro assay ,030304 developmental biology ,0105 earth and related environmental sciences ,ComputingMethodologies_COMPUTERGRAPHICS ,Immunology and Microbiology ,0303 health sciences ,Antigen processing ,Chemistry ,Antigen Specific Activation of T-cells Using Bead-bound Antigens ,Molecular biology ,In vitro ,Medical Laboratory Technology ,medicine.anatomical_structure ,lcsh:Q ,FluoroSpot ,CD8 - Abstract
Graphical abstract, Reliable and sensitive detection of antigen specific cells is essential in several fields of research, whether it concerns monitoring responses to infectious agents or exploring the auto-antigen repertoire in autoimmune diseases. Identification of these cells is however difficult, especially when the cells often are rare and methods not sensitive, specific or practical enough. We propose a novel method of processing antigens before stimulation of cells which consists of covalently binding protein antigen to superparamagnetic micro-beads and using denaturing washes to remove contaminants. Peripheral blood mononuclear cells (PBMCs) from healthy donors were stimulated using both cytomegalovirus and tetanus-diphtheria antigen-beads as well as non-antigenic protein-beads as negative control in an IFNγ FluoroSpot assay in order to detect Th1 and CD8+ responses. The responses toward the antigen beads were both antigen specific and sensitive, with a detection threshold of 1 IFNγ producing T-cell per 18,000 PBMCs. • Covalently binding antigen to paramagnetic beads allows for harsh denaturing washes without loss of antigen. • Microbeads are phagocytosed by antigen presenting cells, resulting in efficient uptake, processing and presentation of the antigens. • The method allows the usage of relatively impure starting antigen material and whole PBMC samples without high background levels in follow up cellular assays.
- Published
- 2019
22. Inhibition on Urease and Thermal Induced Protein Denaturation of commonly used Antiulcer Herbal Products. Study based on in-vitro assays.
- Author
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Khan, Haroon, Khan, Murad Ali, Rauf, Abdul, Haleemi, Ashhad, Fuloria, Shivkanya, and Fuloria, Neeraj Kumar
- Subjects
- *
UREASE , *DENATURATION of proteins , *HERBAL medicine , *ULCER treatment , *ASPIRIN - Abstract
Background: In-vitro urease inhibitory and thermal induced protein denaturation inhibitory activities was performed for two commonly used herbal products Endemali and Akseer ULCER in the treatment of ulcers. Objectives: To evaluate the antiulcer potential of two commonly used herbal products, Endemali, Akseer ULCER. Material and Method: In urease inhibitory assay, enzyme solution, extract, diferent regaents added and absorbance was measured at 630 nm (50 min, pH 8.2) and thiourea used as standard. In protein denaturation assay, the egg albumin was mixed with different concentration of test compounds, buffer absorbance was measured. Aspirin was used as standard. Results: The Endemali had a profound effect on the urease activity in a concentration dependent manner with EC50 value of 0.468 mg/ml. The Akseer ULCER antagonized the urease activity markedly with EC50 value of 0.374 mg/ml. These tested herbal products caused marked inhibition of thermal induced protein denaturation in a concentration dependent manner. The potency in the form of EC50 for Endemali, Akseer ULCER was measured as 323, 337 μg/ml respectively. Conclusion: In short, the tested herbal drug showed strong inhibition on urease activity and inhibition on thermal induced protein denaturation thus our study validated their uses in the treatment of ulcers. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
23. Design, synthesis and biological assessment of new 1-benzyl-4-((4-oxoquinazolin-3(4H)-yl)methyl) pyridin-1-ium derivatives (BOPs) as potential dual inhibitors of acetylcholinesterase and butyrylcholinesterase
- Author
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Mohammad Shafiei, Loghman Firoozpour, Samaneh Zarei, Kouros Divsalar, Ali Asadipour, Tahmineh Akbarzadeh, Alireza Foroumadi, and Maryam Firouzi
- Subjects
0301 basic medicine ,Science (General) ,Aché ,Stereochemistry ,03 medical and health sciences ,chemistry.chemical_compound ,Q1-390 ,0302 clinical medicine ,Bromide ,medicine ,Neurotransmitter ,IC50 ,In-vitro assay ,Butyrylcholinesterase ,H1-99 ,Multidisciplinary ,Chloinestrases ,Oxoquinazolin ,Alzheimer's disease ,Acetylcholinesterase ,language.human_language ,Social sciences (General) ,030104 developmental biology ,chemistry ,Docking (molecular) ,language ,030217 neurology & neurosurgery ,Acetylcholine ,medicine.drug ,Research Article ,Pyridinuim salts - Abstract
Alzheimer's disease (AD), is among the most growing neurodegenerative diseases, which is mainly caused by the acetylcholine neurotransmitter loss in the hippocampus and cortex. Emerging of the dual Acetylcholinesterase (AChE)/Butyrylcholinesterase (BuChE) inhibitors has increased for treating Alzheimer disease. In this study, we would like to report the design and synthesis of a new sequence of 1-benzyl-4-((4-oxoquinazolin-3(4H)-yl)methyl) pyridin-1-ium derivatives (BOPs) assessed as BuChE and AChE inhibitors. Ellman's approach was used for the evaluation of AChE and BuChE inhibitory activities. Moreover, docking research was conducted to predict the action mechanism. Among all synthesized compounds, 1-(3-bromobenzyl)-3-((4-oxoquinazolin-3(4H)-yl)methyl) pyridin-1-ium bromide (BOP-1) was found to be the most active compound with dual activity for inhibition of AChE (IC50 = 5.90 ± 0.07μM), and BuChE (IC50 = 6.76 ± 0.04μM) and 1-(4-chlorobenzyl)-3-((6,7-dimethoxy-4-oxoquinazolin-3(4H)-yl)methyl) pyridin-1-ium chloride (BOP-8) showed the highest AChE inhibitory activity (IC50s = 1.11 ± 0.09 μM). The synthesized compounds BOP-1 and BOP-8 could be proposed as valuable lead compounds for further drug discovery development against AD., Alzheimer's disease; Chloinestrases; Oxoquinazolin; pyridinuim salts; In-vitro assay.
- Published
- 2021
24. Mycobacterial growth inhibition in murine splenocytes as a surrogate for protection against Mycobacterium tuberculosis (M. tb).
- Author
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Marsay, Leanne, Matsumiya, Magali, Tanner, Rachel, Poyntz, Hazel, Griffiths, Kristin L., Stylianou, Elena, Marsh, Philip D., Williams, Ann, Sharpe, Sally, Fletcher, Helen, and McShane, Helen
- Abstract
Summary: Development of an improved vaccine against tuberculosis (TB) is hindered by the lack of a surrogate of protection. Efficacy of new TB vaccines in humans can only be evaluated by expensive and time consuming efficacy trials within TB endemic areas. It is critical that vaccines with the greatest potential to protect are selected for these trials. Mycobacterial growth inhibition assays (MGIAs) have been developed with the hope that these in-vitro functional assays will correlate with protection, which could aid in the selection of the best vaccine candidates. The present study describes the use of the BACTEC system to perform MGIAs in mice. We demonstrate reproducible mycobacterial growth inhibition in splenocytes from BCG immunised mice compared with unimmunised mice (P < 0.023), which corresponded with in-vivo efficacy against Mycobacterium tuberculosis (M. tb) challenge. Microarray data showed extensive differential gene expression in splenocyte responses to ex-vivo BCG stimulation between unimmunised and BCG-immunised mice. T
H 1 responses, including IFN-γ, nitric oxide synthase (NOS2) and Interleukin -17 (IL-17) expression were enhanced in BCG immunised mice, indicating a possible mechanism for mycobacterial growth inhibition. Further investigation into whether the BACTEC MGIA can be used as a surrogate of protection in humans and preclinical animal models is now warranted. [Copyright &y& Elsevier]- Published
- 2013
- Full Text
- View/download PDF
25. Bioanalytical strategies for in-vitro and in-vivo evaluation of the toxicity induced by metallic nanoparticles
- Author
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Luque-Garcia, Jose L., Sanchez-Díaz, Raquel, Lopez-Heras, Isabel, Camara, Carmen, and Martin, Pilar
- Subjects
- *
METAL nanoparticles , *IN vitro studies , *METAL toxicology , *HEALTH , *BIOMARKERS , *ANALYTICAL chemistry - Abstract
Abstract: The increasing use of metallic nanoparticles (MNPs) in a wide variety of applications has led to an urgent need to evaluate the impact of these new materials on human health and the environment. To date, the potential toxicity of MNPs and their interaction mechanisms with cells and living organisms have not been fully addressed. In this article, we discuss the different bioanalytical strategies that have been used for this purpose. We consider different methods aiming to evaluate cellular uptake and localization in cells and tissues, and in-vitro methods for the study of the toxicity induced by MNPs, considering different toxicity markers and high-throughput approaches for the identification of specific targets involved in the cell-MNP interaction. We also discuss special strategies related to the use of animal models to assess in-vivo toxicity of MNPs. [Copyright &y& Elsevier]
- Published
- 2013
- Full Text
- View/download PDF
26. In-vivo and in-vitro testing to assess the bioaccessibility and the bioavailability of arsenic, selenium and mercury species in food samples
- Author
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Moreda-Piñeiro, Jorge, Moreda-Piñeiro, Antonio, Romarís-Hortas, Vanessa, Moscoso-Pérez, Carmen, López-Mahía, Purificación, Muniategui-Lorenzo, Soledad, Bermejo-Barrera, Pilar, and Prada-Rodríguez, Darío
- Subjects
- *
FOOD chemistry , *BIOAVAILABILITY , *ARSENIC , *SELENIUM , *MERCURY (Element) , *CHEMICAL speciation - Abstract
Abstract: In-vivo and in-vitro gastrointestinal (GI) extractions, also known as oral bioaccessibility and bioavailability, are important approaches to assess chemical risk to humans. We give an overview of in-vivo and in-vitro bioaccessibility and bioavailability assays for testing arsenic, selenium and mercury (As, Se and Hg) species from food samples. We critically evaluate the parameters affecting in-vivo and in-vitro processes. In addition, we consider the effect of cooking food on bioaccessibility and bioavailability, and stability and transformation, of species during in-vivo or in-vitro processes. The bioaccessibility and bioavailability of As, Se and Hg species are affected by the sample matrix, cooking food and the experimental conditions applied (gastric and intestinal pH, incubation temperature and residence time). Regarding species degradation and transformation during in-vitro procedures, good stability has been observed for most As species, except for certain arsenosugars. Important transformations during in-vitro processes have been reported for Se species [e.g., conversion of γ-glu-Se-MeSeCys to Se-MeSeCys, and organic Se species (MeSeCys, SeCys2 and SeMet) degradation to inorganic Se]. Finally, we summarize speciation and detection conditions for As, Se and Hg speciation, and quality control to assure reliable measurements. [Copyright &y& Elsevier]
- Published
- 2011
- Full Text
- View/download PDF
27. Autophagy as an ultrastructural marker of heavy metal toxicity in human cord blood hematopoietic stem cells
- Author
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Di Gioacchino, Mario, Petrarca, Claudia, Perrone, Angela, Farina, Massimo, Sabbioni, Enrico, Hartung, Thomas, Martino, Simone, Esposito, Diana L., Lotti, Lavinia Vittoria, and Mariani-Costantini, Renato
- Subjects
- *
BIOMARKERS , *HEMATOPOIETIC stem cells , *TOXICITY testing , *CORD blood , *STEM cell research , *APOPTOSIS - Abstract
Abstract: Stem cells are a key target of environmental toxicants, but little is known about their toxicological responses. We aimed at developing an in-vitro model based on adult human stem cells to identify biomarkers of heavy metal exposure. To this end we investigated the responses of human CD34+ hematopoietic progenitor cells to hexavalent chromium (Cr[VI]) and cadmium (Cd). Parallel cultures of CD34+ cells isolated from umbilical cord blood were exposed for 48 h to 0.1 μM and 10 μM Cr(VI) or Cd. Cultures treated with 10 μM Cr(VI) or Cd showed marked cell loss. Ultrastructural analysis of surviving cells revealed prominent autophagosomes/autophagolysosomes, which is diagnostic of autophagy, associated with mitochondrial damage and replication, dilatation of the rough endoplasmic reticulum and Golgi complex, cytoplasmic lipid droplets and chromatin condensation. Treated cells did not show the morphologic hallmarks of apoptosis. Treatment with 0.1 μM Cr(VI) or Cd did not result in cell loss, but at the ultrastructural level cells showed dilated endoplasmic reticulum and evidence of mitochondrial damage. We conclude that autophagy is implicated in the response of human hematopoietic stem cells to toxic concentrations of Cr(VI) and Cd. Autophagy, which mediates cell survival and death under stress, deserves further evaluation to be established as biomarker of metal exposure. [Copyright &y& Elsevier]
- Published
- 2008
- Full Text
- View/download PDF
28. In-vitro evaluation of the adhesion to polypropylene sutures of non-pigmented, rapidly growing mycobacteria.
- Author
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Zamora, N., Esteban, J., Kinnari, T. J., Celdrán, A., Granizo, J. J., and Zafra, C.
- Subjects
- *
POLYPROPYLENE , *SUTURES , *ADHESION , *MYCOBACTERIA , *MYCOBACTERIAL diseases , *STAPHYLOCOCCAL diseases , *ACTINOMYCETALES , *MEDICAL microbiology , *MEDICAL research - Abstract
The ability of non-pigmented, rapidly growing mycobacteria (NPRGM) to attach to polypropylene sutures was evaluated using an in-vitro assay. Thirty clinical isolates and five culture collection strains of NPRGM, together with Staphylococcus epidermidis ATCC 35983, were tested. Mycobacterium fortuitum and Mycobacterium chelonae showed the highest attachment ability, which differed significantly from the results obtained with Mycobacterium peregrinum. According to these results, NPRGM are able to attach to polypropylene sutures, and the species implicated most frequently in human infection showed increased levels of attachment in comparison with the other mycobacteria studied. [ABSTRACT FROM AUTHOR]
- Published
- 2007
- Full Text
- View/download PDF
29. Nitrogen-doped carbon hollow trunk-like structure as a portable electrochemical sensor for noradrenaline detection in neuronal cells.
- Author
-
Emran, Mohammed Y., Shenashen, Mohamed A., Elmarakbi, Ahmed, Selim, Mahmoud M., and El-Safty, Sherif A.
- Subjects
- *
ELECTROCHEMICAL sensors , *NORADRENALINE , *MESOPOROUS materials , *CARBON , *DETECTION limit - Abstract
To date, the production and development of portable analytical devices for environmental and healthcare applications are rapidly growing. Herein, a portable electrochemical sensor for monitoring of noradrenaline (NA) secreted from living cells using mesoporous carbon-based materials was fabricated. The modification of the interdigitated electrode array (IDA) by nitrogen-doped mesoporous carbon spheres (N-doped MCS) and nitrogen-doped carbon hollow trunk-like structure (N-doped CHT) was used to fabricate the NA sensor. The N-doped CHT surface shows multiple holes distributed with micrometer-sized open holes (1–2 μm) and nanometer-sized thin walls (∼98 nm). The N-doped CHT surface heterogeneity of wrinkled and twisted hollow trunk structures improve the diffusion pathway and the NA molecules loading. The N-doped CHT/IDA showed a highly selective assay for monitoring of NA with high sensitivity (1770 μA/μM × cm2), a low detection limit (0.005 μM), and a wide linear range (0.01–0.3 μM). The N-doped CHT/IDA monitored the NA secreted from PC12 cells under various concentrations of simulation agents (KCl). The designed N-doped CHT/IDA provides a portable NA-sensor assay with facile signaling, good stability, high biocompatibility, in-vitro assay compatibility, and good reproducibility. Therefore, the designed sensor can be used as a portable sensor for NA detection in live cells and can be matched with portable smartphones after further developments. Design of portable sensor for screening of noradrenaline (NA) secreted from living cells (PC12 cells) is fabricated based on nitrogen-doped carbon hollow trunk structure (N-doped CHT). The N-doped CHT/IDA shows highly sensitive and selective portable sensor assay for monitoring of NA in living cells. [Display omitted] • Mesoporous carbon is used for portable analytical device for healthcare applications. • N-doped carbon (N-CHT) is used to modified interdigitated electrode array (IDA). • The N-CHT/IDA showed a highly selective assay for NA molecules monitoring. • Sensitive chipset NA-sensor based on N-CHT/IDA was designed with fast response time. • In-vitro assay monitoring of sereted NA in living cells have been established. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
30. Green synthesis approach for new Schiff's-base complexes; theoretical and spectral based characterization with in-vitro and in-silico screening.
- Author
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Alharbi, Arwa, Alsoliemy, Amerah, Alzahrani, Seraj O., Alkhamis, Kholood, Almehmadi, Samar J., Khalifa, Mohamed E., Zaky, Rania, and El-Metwaly, Nashwa M.
- Subjects
- *
MEDICAL screening , *LIVER cells , *INHIBITION (Chemistry) , *BINDING constant , *LIVER cancer , *CANDIDA albicans - Abstract
• Synthesized Schiff base complexes were studied by available tools. • A conductometry study was carried out in order to extract important parameters. • In vitro tests were performed on bacteria, fungus, free radicals, and cancer cell lines. • To strengthen the study, extensive theoretical implementations were carried out. Ball milling was used to obtain new Schiff-base complexes from Co(II), Fe(III), Ni(II), and Zn(II) ions in their solid form, which is considered a green method of preparation. Several spectroscopic (IR, UV–Vis, 1H NMR, Mass, SEM, EDX, XRD) and analytical approaches were used to suggest the geometries of isolated compounds. Coats–Redfern and Horowitz–Metzger methods were used to compute the kinetic and thermodynamic parameters of Zn(II) complex (i.e.). Furthermore, conductometry was used to estimate both formation/association constants of Co(II) complex (i.e.) in solution at 290.15 K. The feature of the complex in solution may offer a good view about it in its solid state. Standard methods were applied to test the antibacterial activity of ligand and complexes to TOS aureus, E. coli and Candida albicans fungus. To assess their inhibitory effect, ABTS-antioxidant screening and cytotoxicity against liver cancer cells (HepG2) were also performed. Most complexes showed mild to considerable activity towards the selected microorganisms and liver cancer cell line, respectively. The structural forms were optimized using molecular modeling, which then confirmed the binding mechanism provided by spectral analyses. To investigate the degree of inhibition for new drugs versus three selected proteins (1dee, 5uw2 and 7jx9), two in-silico techniques were used: Pharmit link and Molecular Operating Environmental module (MOE, vs 2018). The docking patterns as well as the interaction data were acquired and analyzed. The high consistency of in-vitro and in-silico outcomes lends credence to computational treatments that must be done on developed medications before they can be used in practice. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
31. In-vitro viability of bone scaffolds fabricated using the adaptive foam reticulation technique.
- Author
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Winnett J, Jumbu N, Cox S, Gibbons G, Grover LM, Warnett J, Williams MA, Dancer CEJ, and Mallick KK
- Subjects
- Bone and Bones, Durapatite chemistry, Porosity, Bone Regeneration, Tissue Scaffolds chemistry
- Abstract
The adaptive foam reticulation technique combines the foam reticulation and freeze casting methodologies of fabricating bone reparative scaffolds to offer a potential alternative to autografts. For the first time this paper studies the effect of processing on the mechanical properties and in-vitro cell growth of controllably generating a hierarchical structure of macro- (94 ± 6 to 514 ± 36 μm) and microporosity (2-30 μm) by the inclusion of camphene as a porogen during processing. Scaffolds were produced with porogen additions of 0-25 wt%. Porosity values of the structures of 85-96% were determined using the Archimedes technique and verified using X-ray Computed Tomography. The strength of the hydroxyapatite scaffolds, 5.70 ± 1.0 to 159 ± 61 kPa, correlated to theoretically determined values, 3.71 ± 0.8 to 134 ± 12 kPa, calculated by the novel incorporation of a shape factor into a standard equation. Fibroblast (3T3) and pre-osteoblast (MC3T3) cell growth was found to be significantly (P < 0.005) improved using 25 wt% porogen. This was supported by increased levels of alkaline phosphatase and was thought to result from greater dissolution as quantified by increased calcium levels in incubating media. The combination of these properties renders adaptive foam reticulation-fabricated scaffolds suitable for non-structural bone regenerative applications in non-load bearing bone defects., (Copyright © 2022 The Authors. Published by Elsevier B.V. All rights reserved.)
- Published
- 2022
- Full Text
- View/download PDF
32. Facile solvothermal synthesis of ultrathin spinel ZnMn2O4 nanospheres: An efficient electrocatalyst for in vivo and in vitro real time monitoring of H2O2.
- Author
-
Annalakshmi, Muthaiah, Kumaravel, Sakthivel, Balamurugan, T.S.T., Chen, Shen-Ming, and He, Ju-Liang
- Subjects
- *
ZINC oxide , *TOOTHPASTE , *SPINEL , *HYDROGEN peroxide , *DETECTION limit - Abstract
[Display omitted] • The ultrathin ZnMn 2 O 4 (ZMO) nanospheres were prepared by facile solvothermal method. • The ZMO exhibited wide linearity (20 nM-10 mM) with low detection limit (8.3 nM). • The developed biosensor showed rapid response (> 3s), high selectivity and stability. • The proposed sensor was applied for in-vivo and in-vitro real-time analysis of H 2 O 2.. Hydrogen peroxide (H 2 O 2) is a renowned industrial oxidant that plays a significant role in cell biology, and pathogenesis. On this note, we propose a simple Zinc Manganese Oxide (ZnMn 2 O 4 ; ZMO) based H 2 O 2 sensor for rapid in-situ tracking and determination of H 2 O 2 from live cells, and bio-samples. The ZMO catalyst have been synthesized via simple scalable protocol; surface morphology, elemental composition, electronic states, crystallinity, and other physiochemical properties are studied and discussed in-detail using various spectroscopic tools. The ZMO modified electrode displays an excellent electrochemical activity toward H 2 O 2 sensing with a wide dynamic range (20 nM-10 mM), low detection limit (8.3 nM), excellent selectivity, reproducibility, operational stability, and rapid response time (<3 s). Further, the ZMO modified electrode have been found successful at in-vivo real-time tracking of H 2 O 2 released from live HeLa cells, and in-vitro analysis of H 2 O 2 spiked in water, tooth paste, and human serum samples. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
33. Alcohol ethoxycarboxylates—Mild, high-foaming surfactants for personal-care products.
- Author
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Schmidt, W., Durante, D., Gingell, R., and Harbell, J.
- Abstract
Alcohol ethoxycarboxylates (AEC) may be derived from alcohol ethoxylates (AEO) either by reaction of the nonionic surfactant with monochloroacetic acid (MCAA) or by oxidation. If MCAA is used, a -CH
2 COOH unit is added to the AEO. When an AEO is oxidized, the terminal -CH2 OH group is selectively converted to -COOH. By use of proprietary carefully controlled oxidation technology, a variety of AEC surfactants have been synthesized. These surfactants exhibit good foaming and excellent line soap dispersion, and they allow formulation of high-quality personal-care products. Starter formulations have been investigated with AEC, both in shampoos and liquid hand cleaners. These formulations had the viscosity and foaming found in a survey of commercially available products. A shampoo and a liquid soap formulation with AEC were subjected to in-vitro assays to assess the potential for irritation to the skin or eyes. The assay results predict these formulations to cause minimal irritation, similar to commercial products. [ABSTRACT FROM AUTHOR]- Published
- 1997
- Full Text
- View/download PDF
34. In-vitro ovicidal activity of Azadirachta indica leaf extracts against Haemonchus contortus eggs.
- Author
-
SINGH, D., SWARNKAR, C. P., KHAN, F. A., and BHAGWAN, P. S. K.
- Abstract
The article presents a study which examined the in-vitro ovicidal activity of Azadirachta indica leaf extracts against Haemonchus contortus eggs. A survey conducted in Rajasthan, India, showed that control of gastrointestinal nematodosis in sheep is mainly accomplished by the use of anthelmintics and that has not only resulted in emergence of anthelmintic resistance in parasites but has posed the problem of chemical residue in animal tissues and environment. According to the study, only aqueous extract of A. indica leaves demonstrated significant reduction in egg embryonation and egg hatching at a concentration of 1.25 milligrams/milliliter which suggests the presence of potent embryonation and hatching.
- Published
- 2008
35. Angiogenesis
- Subjects
VASCULAR-PERMEABILITY FACTOR ,INTRAMUSCULAR GENE-TRANSFER ,MATRIX METALLOPROTEINASE INHIBITOR ,CELL LUNG-CANCER ,COLLAGEN-INDUCED ARTHRITIS ,ENDOTHELIAL GROWTH-FACTOR ,NECROSIS-FACTOR-ALPHA ,RECEPTOR TYROSINE KINASES ,SIGNAL-TRANSDUCTION PATHWAYS ,IN-VITRO ASSAY - Abstract
Angiogenesis, or the formation of new blood vessels out of pre-existing capillaries, is a sequence of events that is fundamental to many physiologic and pathologic processes such as cancer, ischemic diseases, and chronic inflammation. With the identification of several proangiogenic molecules such as the vascular endothelial cell growth factor, the fibroblast growth factors (like in FGFs), and the angiopoietins, and the recent description of specific inhibitors of angiogenesis such as platelet factor-4, angiostatin, endostatin, and vasostatin, it is recognized that therapeutic interference with vasculature formation offers a tool for clinical applications in various pathologies. Whereas inhibition of angiogenesis can prevent diseases with excessive vessel growth such as cancer, diabetes retinopathy, and arthritis, stimulation of angiogenesis would be beneficial in the treatment of diseases such as coronary artery disease and critical limb ischemia in diabetes. In this review we highlight the current knowledge on angiogenesis regulation and report on the recent findings in angiogenesis research and clinical studies. We also discuss the potentials, limitations, and challenges within this field of research, in light of the development of new therapeutic strategies for diseases in which angiogenesis plays an important role.
- Published
- 2000
36. Sensitive detection of antigen-specific T-cells using bead-bound antigen for in vitro re-stimulation.
- Author
-
Bronge M, Kaiser A, Carvalho-Queiroz C, Nilsson OB, Ruhrmann S, Holmgren E, Olsson T, Gafvelin G, and Grönlund H
- Abstract
Reliable and sensitive detection of antigen specific cells is essential in several fields of research, whether it concerns monitoring responses to infectious agents or exploring the auto-antigen repertoire in autoimmune diseases. Identification of these cells is however difficult, especially when the cells often are rare and methods not sensitive, specific or practical enough. We propose a novel method of processing antigens before stimulation of cells which consists of covalently binding protein antigen to superparamagnetic micro-beads and using denaturing washes to remove contaminants. Peripheral blood mononuclear cells (PBMCs) from healthy donors were stimulated using both cytomegalovirus and tetanus-diphtheria antigen-beads as well as non-antigenic protein-beads as negative control in an IFNγ FluoroSpot assay in order to detect Th1 and CD8
+ responses. The responses toward the antigen beads were both antigen specific and sensitive, with a detection threshold of 1 IFNγ producing T-cell per 18,000 PBMCs. •Covalently binding antigen to paramagnetic beads allows for harsh denaturing washes without loss of antigen.•Microbeads are phagocytosed by antigen presenting cells, resulting in efficient uptake, processing and presentation of the antigens.•The method allows the usage of relatively impure starting antigen material and whole PBMC samples without high background levels in follow up cellular assays., Competing Interests: We wish to draw the attention of the editor to the following facts which may be considered as potential conflicts of interest. There are pending patents regarding parts of the methods presented in this manuscript, more precisely the usage of antigen-beads for detection of antigen-specific T-cells. Mattias Bronge and Hans Grönlund are the inventors of said patents which are held by the private company TCER AB. Hans Grönlund is a co-founder of TCER AB and Claudia Carvalho-Queiroz, Ola Nilsson and Andreas Kaiser hold positions at TCER AB. The study has been partly funded by grants from CBD solutions, Neuroförbundet, Swedish Research Council (2017-00777), Swedish Brain Foundation, Margareta af Ugglas Foundation and Stratneuro. None of the funding sources have had a role in the study design, collection, analysis or interpretation of the data.- Published
- 2019
- Full Text
- View/download PDF
37. Mycobacterial growth inhibition in murine splenocytes as a surrogate for protection against Mycobacterium tuberculosis (M. tb)
- Author
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Magali Matsumiya, Helen A. Fletcher, Hazel C. Poyntz, Sally Sharpe, Kristin L. Griffiths, Elena Stylianou, Helen McShane, Rachel Tanner, Leanne Marsay, Ann Williams, and Philip Marsh
- Subjects
Microbiology (medical) ,Tuberculosis ,Immunology ,Colony Count, Microbial ,Microbiology ,Mycobacterium tuberculosis ,chemistry.chemical_compound ,Mice ,Gene expression ,Splenocyte ,medicine ,Animals ,BCG ,In-vitro assay ,Cells, Cultured ,biology ,Microarray analysis techniques ,Interleukin ,biology.organism_classification ,medicine.disease ,Virology ,Mycobacterium bovis ,Nitric oxide synthase ,Mice, Inbred C57BL ,Disease Models, Animal ,Infectious Diseases ,chemistry ,Gene Expression Regulation ,biology.protein ,BCG Vaccine ,Cytokines ,Female ,Growth inhibition ,Inflammation Mediators ,Vaccine ,Spleen - Abstract
Development of an improved vaccine against tuberculosis (TB) is hindered by the lack of a surrogate of protection. Efficacy of new TB vaccines in humans can only be evaluated by expensive and time consuming efficacy trials within TB endemic areas. It is critical that vaccines with the greatest potential to protect are selected for these trials. Mycobacterial growth inhibition assays (MGIAs) have been developed with the hope that these in-vitro functional assays will correlate with protection, which could aid in the selection of the best vaccine candidates. The present study describes the use of the BACTEC system to perform MGIAs in mice. We demonstrate reproducible mycobacterial growth inhibition in splenocytes from BCG immunised mice compared with unimmunised mice (P < 0.023), which corresponded with in-vivo efficacy against Mycobacterium tuberculosis (M. tb) challenge. Microarray data showed extensive differential gene expression in splenocyte responses to ex-vivo BCG stimulation between unimmunised and BCG-immunised mice. TH1 responses, including IFN-γ, nitric oxide synthase (NOS2) and Interleukin -17 (IL-17) expression were enhanced in BCG immunised mice, indicating a possible mechanism for mycobacterial growth inhibition. Further investigation into whether the BACTEC MGIA can be used as a surrogate of protection in humans and preclinical animal models is now warranted. © 2013 Published by Elsevier Ltd.
- Published
- 2013
38. Validation of an enzyme-linked immunosorbent assay for the quantification of human IgG directed against the repeat region of the circumsporozoite protein of the parasite Plasmodium falciparum
- Author
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Marianne Dewerchin, Joe Cohen, Vincent Dewar, Geert Leroux-Roels, Erik Jongert, Eva Van Braeckel, Christine Swysen, Marie-Ange Demoitié, Frédéric Clement, Isabelle Desombere, and Pierre Cambron
- Subjects
Protozoan Proteins ,Antibodies, Protozoan ,Circumsporozoite protein ,Immunoglobulin G ,Epitope ,Limit of Detection ,Validation ,Medicine and Health Sciences ,Malaria, Falciparum ,biology ,Malaria vaccine ,Immunogenicity ,RANDOMIZED CONTROLLED-TRIAL ,IN-VITRO ASSAY ,Recombinant Proteins ,Infectious Diseases ,ESCHERICHIA-COLI ,PHASE 2A TRIAL ,Epitopes, B-Lymphocyte ,Adult ,AFRICAN CHILDREN ,Plasmodium falciparum ,lcsh:Arctic medicine. Tropical medicine ,medicine.drug_class ,lcsh:RC955-962 ,R32LR ,Antigens, Protozoan ,Monoclonal antibody ,lcsh:Infectious and parasitic diseases ,Antigen ,Enzyme-linked immunosorbent assay ,Malaria Vaccines ,SYNTHETIC PEPTIDES ,parasitic diseases ,medicine ,Animals ,Humans ,CANDIDATE MALARIA VACCINE ,lcsh:RC109-216 ,PROTECTIVE ANTIBODIES ,NAIVE ADULTS ,fungi ,Methodology ,biology.organism_classification ,Virology ,Molecular biology ,Malaria ,EXPANDED-PROGRAM ,biology.protein ,Parasitology - Abstract
Background Several pre-erythrocytic malaria vaccines based on the circumsporozoite protein (CSP) antigen of Plasmodium falciparum are in clinical development. Vaccine immunogenicity is commonly evaluated by the determination of anti-CSP antibody levels using IgG-based assays, but no standard assay is available to allow comparison of the different vaccines. Methods The validation of an anti-CSP repeat region enzyme-linked immunosorbent assay (ELISA) is described. This assay is based on the binding of serum antibodies to R32LR, a recombinant protein composed of the repeat region of P. falciparum CSP. In addition to the original recombinant R32LR, an easy to purify recombinant His-tagged R32LR protein has been constructed to be used as solid phase antigen in the assay. Also, hybridoma cell lines have been generated producing human anti-R32LR monoclonal antibodies to be used as a potential inexhaustible source of anti-CSP repeats standard, instead of a reference serum. Results The anti-CSP repeats ELISA was shown to be robust, specific and linear within the analytical range, and adequately fulfilled all validation criteria as defined in the ICH guidelines. Furthermore, the coefficient of variation for repeatability and intermediate precision did not exceed 23%. Non-interference was demonstrated for R32LR-binding sera, and the assay was shown to be stable over time. Conclusions This ELISA, specific for antibodies directed against the CSP repeat region, can be used as a standard assay for the determination of humoral immunogenicity in the development of any CSP-based P. falciparum malaria vaccine.
- Published
- 2012
39. Effect of heating and glycation on the allergenicity of 2S albumins (Ara h 2/6) from peanut
- Author
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Zsolt Szépfalusi, Laurian Zuidmeer-Jongejan, Per Stahl Skov, Karine Adel-Patient, Neil M. Rigby, Huub F. J. Savelkoul, Harry J. Wichers, Alan R. Mackie, Janneke Ruinemans-Koerts, Hervé Bernard, J.-M. Wal, Fany Blanc, Laetitia Przybylski-Nicaise, Phil Johnson, Barbara Ballmer-Weber, Clare Mills, Ad Jansen, Yvonne M. Vissers, University of Zurich, Adel-Patient, K, Wageningen University and Research Centre (WUR), Unité de Recherche Immuno-Allergie Alimentaire, Institut National de la Recherche Agronomique (INRA), RefLab ApS, Partenaires INRAE, Institute of Food Research, University Hospital Zurich, Vrije universiteit = Free university of Amsterdam [Amsterdam] (VU), Medizinische Universität Wien = Medical University of Vienna, Rijnstate Hospital, Radboud university [Nijmegen], EU [51400], Biological and Biotechnological Sciences Research Council in the UK, VU University Amsterdam, AII - Amsterdam institute for Infection and Immunity, and Experimental Immunology
- Subjects
Protein Folding ,Arachis ,[SDV]Life Sciences [q-bio] ,Peanut allergy ,B-CELL ,Glycobiology ,lcsh:Medicine ,digestion ,medicine.disease_cause ,Immunoglobulin E ,maillard reaction ,Biochemistry ,Protein Structure, Secondary ,chemistry.chemical_compound ,food allergens ,0302 clinical medicine ,Allergen ,IGE-BINDING EPITOPES ,Glycation ,FBR Fresh Supply Chains ,Denaturation (biochemistry) ,LIPTRANSFER PROTEIN ,lcsh:Science ,Multidisciplinary ,biology ,Food Chemistry ,Chemistry ,Allergy and Hypersensitivity ,food and beverages ,10177 Dermatology Clinic ,04 agricultural and veterinary sciences ,IN-VITRO ASSAY ,040401 food science ,major allergen ,T-CELL RESPONSES ,MAILLARD REACTION ,FOOD ALLERGENS ,CYTOKINE PRODUCTION ,MAJOR ALLERGEN ,DIGESTION ,Medicine ,cytokine production ,ige-binding epitopes ,Plant lipid transfer proteins ,Histamine ,Research Article ,Protein Binding ,Protein Structure ,Immunology ,in-vitro assay ,Biophysics ,Celbiologie en Immunologie ,610 Medicine & health ,1100 General Agricultural and Biological Sciences ,Basophil degranulation ,b-cell ,Protein Chemistry ,03 medical and health sciences ,0404 agricultural biotechnology ,1300 General Biochemistry, Genetics and Molecular Biology ,Albumins ,Levensmiddelenchemie ,medicine ,Biology ,Glycoproteins ,VLAG ,1000 Multidisciplinary ,lcsh:R ,Proteins ,lipid transfer protein ,Allergens ,Antigens, Plant ,t-cell responses ,medicine.disease ,Glucose ,030228 respiratory system ,Cell Biology and Immunology ,biology.protein ,Leukocytes, Mononuclear ,WIAS ,lcsh:Q ,Clinical Immunology - Abstract
International audience; Background: Peanut allergy is one of the most common and severe food allergies, and processing is known to influence the allergenicity of peanut proteins. We aimed to establish the effect of heating and glycation on the IgE-binding properties and biological activity of 2S albumins (Ara h 2/6) from peanut. Methodology/Principal Findings: Native Ara h 2/6 was purified from raw peanuts and heated in solution (15 min, 110 degrees C) in the presence or absence of glucose. Ara h 2 and 6 were also purified from roasted peanut. Using PBMC and sera from peanut-allergic patients, the cellular proliferative potency and IgE reactivity (reverse EAST inhibition) and functionality (basophil degranulation capacity) of allergens were assessed. Heating Ara h 2/6 at 110 degrees C resulted in extensive denaturation, hydrolysis and aggregation of the protein, whilst Ara h 2 and 6 isolated from roasted peanut retained its native conformation. Allergen stimulation of PBMC induced proliferation and Th2 cytokine secretion which was unaffected by thermal processing. Conversely, IgE reactivity and functionality of Ara h 2/6 was decreased by heating. Whilst heating-glycation further reduced the IgE binding capacity of the proteins, it moderated their loss of histamine releasing capacity. Ara h 2 and 6 purified from roasted peanut demonstrated the same IgE reactivity as unheated, native Ara h 2/6. Conclusions/Significance: Although no effect of processing on T-cell reactivity was observed, heat induced denaturation reduced the IgE reactivity and subsequent functionality of Ara h 2/6. Conversely, Ara h 2 and 6 purified from roasted peanut retained the structure and IgE reactivity/functionality of the native protein which may explain the allergenic potency of this protein. Through detailed molecular study and allergenicity assessment approaches, this work then gives new insights into the effect of thermal processing on structure/allergenicity of peanut proteins.
- Published
- 2011
- Full Text
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40. In-vitro evaluation of the adhesion to polypropylene sutures of non-pigmented, rapidly growing mycobacteria
- Author
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Angel Celdrán, Juan-José Granizo, N. Zamora, Jaime Esteban, C. Zafra, and Teemu J. Kinnari
- Subjects
Microbiology (medical) ,Micrococcaceae ,in-vitro assay ,Attachment ,Mycobacterium chelonae ,Biology ,Mycobacterium peregrinum ,Polypropylenes ,Bacterial Adhesion ,Microbiology ,Mycobacterium ,polypropylene sutures ,non-pigmented mycobacteria ,Staphylococcus epidermidis ,Mycobacterium Infections ,Sutures ,Nontuberculous Mycobacteria ,Mycobacterium spp ,General Medicine ,Adhesion ,biology.organism_classification ,Infectious Diseases ,Evaluation Studies as Topic ,Mycobacterium fortuitum ,Bacteria - Abstract
The ability of non-pigmented, rapidly growing mycobacteria (NPRGM) to attach to polypropylene sutures was evaluated using an in-vitro assay. Thirty clinical isolates and five culture collection strains of NPRGM, together with Staphylococcus epidermidis ATCC 35983, were tested. Mycobacterium fortuitum and Mycobacterium chelonae showed the highest attachment ability, which differed significantly from the results obtained with Mycobacterium peregrinum. According to these results, NPRGM are able to attach to polypropylene sutures, and the species implicated most frequently in human infection showed increased levels of attachment in comparison with the other mycobacteria studied.
- Published
- 2007
41. Autophagy as an ultrastructural marker of heavy metal toxicity in human cord blood hematopoietic stem cells
- Author
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Thomas Hartung, Lavinia Vittoria Lotti, Mario Di Gioacchino, Massimo Farina, Claudia Petrarca, Simone Martino, Renato Mariani-Costantini, Enrico Sabbioni, A Perrone, and Diana L. Esposito
- Subjects
Pathology ,medicine.medical_specialty ,Environmental Engineering ,cadmium ,in-vitro assay ,autophagy ,cd34+ cells ,cd34+cells ,chromium ,stem cells ,toxicity ,umbilical cord blood ,CD34 ,Antigens, CD34 ,Biology ,Blood cell ,Microscopy, Electron, Transmission ,Metals, Heavy ,medicine ,Autophagy ,Environmental Chemistry ,Humans ,Waste Management and Disposal ,Endoplasmic reticulum ,Fetal Blood ,Flow Cytometry ,Hematopoietic Stem Cells ,Pollution ,Cell biology ,Haematopoiesis ,medicine.anatomical_structure ,Apoptosis ,Cord blood ,Stem cell - Abstract
Stem cells are a key target of environmental toxicants, but little is known about their toxicological responses. We aimed at developing an in-vitro model based on adult human stem cells to identify biomarkers of heavy metal exposure. To this end we investigated the responses of human CD34+ hematopoietic progenitor cells to hexavalent chromium (Cr[VI]) and cadmium (Cd). Parallel cultures of CD34+ cells isolated from umbilical cord blood were exposed for 48 h to 0.1 microM and 10 microM Cr(VI) or Cd. Cultures treated with 10 microM Cr(VI) or Cd showed marked cell loss. Ultrastructural analysis of surviving cells revealed prominent autophagosomes/autophagolysosomes, which is diagnostic of autophagy, associated with mitochondrial damage and replication, dilatation of the rough endoplasmic reticulum and Golgi complex, cytoplasmic lipid droplets and chromatin condensation. Treated cells did not show the morphologic hallmarks of apoptosis. Treatment with 0.1 microM Cr(VI) or Cd did not result in cell loss, but at the ultrastructural level cells showed dilated endoplasmic reticulum and evidence of mitochondrial damage. We conclude that autophagy is implicated in the response of human hematopoietic stem cells to toxic concentrations of Cr(VI) and Cd. Autophagy, which mediates cell survival and death under stress, deserves further evaluation to be established as biomarker of metal exposure.
- Published
- 2007
42. Effect of Heating and Glycation on the Allergenicity of 2S Albumins (Ara h 2/6) from Peanut
- Author
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Vissers, Y.M., Blanc, F., Stahl Skov, P., Johnson, P.E., Rigby, N.M., Przybylski-Nicaise, L., Bernhard, H., Wal, J.M., Ballmer-Weber, B., Zuidmeer-Jongejan, L., Szepfalusi, Z., Ruinemans-Koerts, J., Jansen, A.P.H., Savelkoul, H.F.J., Wichers, H.J., Mackie, A.R., Mills, E.N.C., Adel-Patient, K., Vissers, Y.M., Blanc, F., Stahl Skov, P., Johnson, P.E., Rigby, N.M., Przybylski-Nicaise, L., Bernhard, H., Wal, J.M., Ballmer-Weber, B., Zuidmeer-Jongejan, L., Szepfalusi, Z., Ruinemans-Koerts, J., Jansen, A.P.H., Savelkoul, H.F.J., Wichers, H.J., Mackie, A.R., Mills, E.N.C., and Adel-Patient, K.
- Abstract
Background Peanut allergy is one of the most common and severe food allergies, and processing is known to influence the allergenicity of peanut proteins. We aimed to establish the effect of heating and glycation on the IgE-binding properties and biological activity of 2S albumins (Ara h 2/6) from peanut. Methodology/Principal Findings Native Ara h 2/6 was purified from raw peanuts and heated in solution (15 min, 110°C) in the presence or absence of glucose. Ara h 2 and 6 were also purified from roasted peanut. Using PBMC and sera from peanut-allergic patients, the cellular proliferative potency and IgE reactivity (reverse EAST inhibition) and functionality (basophil degranulation capacity) of allergens were assessed. Heating Ara h 2/6 at 110°C resulted in extensive denaturation, hydrolysis and aggregation of the protein, whilst Ara h 2 and 6 isolated from roasted peanut retained its native conformation. Allergen stimulation of PBMC induced proliferation and Th2 cytokine secretion which was unaffected by thermal processing. Conversely, IgE reactivity and functionality of Ara h 2/6 was decreased by heating. Whilst heating-glycation further reduced the IgE binding capacity of the proteins, it moderated their loss of histamine releasing capacity. Ara h 2 and 6 purified from roasted peanut demonstrated the same IgE reactivity as unheated, native Ara h 2/6. Conclusions/Significance Although no effect of processing on T-cell reactivity was observed, heat induced denaturation reduced the IgE reactivity and subsequent functionality of Ara h 2/6. Conversely, Ara h 2 and 6 purified from roasted peanut retained the structure and IgE reactivity/functionality of the native protein which may explain the allergenic potency of this protein. Through detailed molecular study and allergenicity assessment approaches, this work then gives new insights into the effect of thermal processing on structure/allergenicity of peanut proteins.
- Published
- 2011
43. In Vitro Reconstitution of the Endoplasmic Reticulum.
- Author
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Ferencz CM, Guigas G, Veres A, Neumann B, Stemmann O, and Weiss M
- Subjects
- Animals, Cell Extracts, Cytosol metabolism, Female, HeLa Cells, Humans, Hydrogel, Polyethylene Glycol Dimethacrylate pharmacology, Image Processing, Computer-Assisted, Microsomes metabolism, Xenopus laevis, Cytological Techniques methods, Endoplasmic Reticulum metabolism
- Abstract
Reconstitution of cellular organelles in vitro offers the possibility to perform quantitative and qualitative experiments in a controlled environment that cannot be done with the same accuracy in living cells. Following a previous report, the subsequent list of protocols describes how to reconstitute and quantify a tubular ER network in vitro based on purified microsomes from culture cells and cytosol from Xenopus laevis egg extracts. Biological material preparation and reconstitution assays require mostly basic laboratory instrumentation and chemicals, and can be executed without any specific training, making them appealing to a wide range of laboratories. Moreover, to promote conditions that are markedly more reflective of in vivo environments, this method describes for the first time in the literature, the purification of microsomes from HeLa cells in some detail. Basic Protocol 1 in this article describes the reconstitution process on different substrates including the associated fluorescence imaging process. Purification of ER microsomes and cytosol, both of which are needed for this approach, are described in detail in Support Protocols 1 and 2, respectively. Coating of surfaces with polyacrylamide gels is described in Support Protocol 3. Basic Protocol 2 outlines how to segment and skeletonize fluorescence images of ER networks, and how to quantify segment lengths between the network's branching points. The described quantitative evaluation provides a meaningful approach to analyze the topology and geometry of organelle structures. © 2017 by John Wiley & Sons, Inc., (Copyright © 2017 John Wiley & Sons, Inc.)
- Published
- 2017
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44. In-vitro Assays of Meloidogyne incognita and Heterodera glycines for Detection of Nematode-antagonistic Fungal Compounds.
- Author
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Nitao JK, Meyer SL, and Chitwood DJ
- Abstract
In-vitro methods were developed to test fungi for production of metabolites affecting nematode egg hatch and mobility of second-stage juveniles. Separate assays were developed for two nematodes: root-knot nematode (Meloidogyne incognita) and soybean cyst nematode (Heterodera glycines). For egg hatch to be successfully assayed, eggs must first be surface-disinfested to avoid the confounding effects of incidental microbial growth facilitated by the fungal culture medium. Sodium hypochlorite was more effective than chlorhexidine diacetate or formaldehyde solutions at surface-disinfesting soybean cyst nematode eggs from greenhouse cultures. Subsequent rinsing with sodium thiosulfate to remove residual chlorine from disinfested eggs did not improve either soybean cyst nematode hatch or juvenile mobility. Soybean cyst nematode hatch in all culture media was lower than in water. Sodium hypochlorite was also used to surface-disinfest root-knot nematode eggs. In contrast to soybean cyst nematode hatch, root-knot nematode hatch was higher in potato dextrose broth medium than in water. Broth of the fungus Fusarium equiseti inhibited root-knot nematode egg hatch and was investigated in more detail. Broth extract and its chemical fractions not only inhibited egg hatch but also immobilized second-stage juveniles that did hatch, confirming that the fungus secretes nematode-antagonistic metabolites.
- Published
- 1999
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