572 results on '"Ravi, S."'
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2. Chemistry, Biosynthesis and Pharmacology of Streptonigrin: An Old Molecule with Future Prospects for New Drug Design, Development and Therapy
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Nabihah Nasir N, Sekar M, Ravi S, Wong LS, Sisinthy SP, Gan SH, Subramaniyan V, Chidambaram K, Mat Rani NNI, Begum MY, Ramar M, Safi SZ, Selvaraj S, Chinna Maruthu SK, Fuloria S, Fuloria NK, Lum PT, and Djearamane S
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streptonigrin ,chemistry ,biosynthesis ,pharmacology ,anticancer ,antibacterial ,Therapeutics. Pharmacology ,RM1-950 - Abstract
Naurah Nabihah Nasir,1 Mahendran Sekar,2,3 Subban Ravi,4 Ling Shing Wong,5 Sreenivas Patro Sisinthy,6 Siew Hua Gan,2 Vetriselvan Subramaniyan,7 Kumarappan Chidambaram,8 Nur Najihah Izzati Mat Rani,6 M Yasmin Begum,9 Mohankumar Ramar,10 Sher Zaman Safi,11 Siddharthan Selvaraj,12 Senthil Kumar Chinna Maruthu,13 Shivkanya Fuloria,14 Neeraj Kumar Fuloria,14 Pei Teng Lum,1 Sinouvassane Djearamane15 1Department of Pharmaceutical Chemistry, Faculty of Pharmacy and Health Sciences, Royal College of Medicine Perak, Universiti Kuala Lumpur, Ipoh, Perak, 30450, Malaysia; 2School of Pharmacy, Monash University Malaysia, Bandar Sunway, Selangor, 47500, Malaysia; 3Center for Transdisciplinary Research, Department of Pharmacology, Saveetha Institute of Medical and Technical Sciences, Saveetha Dental College and Hospital, Saveetha University, Chennai, Tamil Nadu, 600077, India; 4Department of Chemistry, Karpagam Academy of Higher Education, Coimbatore, Tamil Nadu, 641021, India; 5Faculty of Health and Life Sciences, INTI International University, Nilai, 71800, Malaysia; 6Faculty of Pharmacy and Health Sciences, Royal College of Medicine Perak, Universiti Kuala Lumpur, Ipoh, Perak, 30450, Malaysia; 7Jeffrey Cheah School of Medicine and Health Sciences, Monash University Malaysia, Bandar Sunway, Subang Jaya, Selangor, Malaysia; 8Department of Pharmacology, College of Pharmacy, King Khalid University, Abha, 62529, Saudi Arabia; 9Department of Pharmaceutics, College of Pharmacy, King Khalid University, Abha, 61421, Saudi Arabia; 10Department of Surgical Research, Rhode Island Hospital, Alpert Medical School, Brown University, Providence, RI, 02903, USA; 11Faculty of Medicine, Bioscience and Nursing, MAHSA University, Jenjarom, Selangor, 42610, Malaysia; 12Faculty of Dentistry, AIMST University, Bedong, Kedah, 08100, Malaysia; 13Department of Pharmacology, Karpagam College of Pharmacy, Coimbatore, Tamilnadu, 641032, India; 14Faculty of Pharmacy, AIMST University, Bedong, Kedah, 08100, Malaysia; 15Department of Biomedical Science, Faculty of Science, Universiti Tunku Abdul Rahman, Kampar, Perak, 31900, MalaysiaCorrespondence: Ling Shing Wong, Faculty of Health and Life Sciences, INTI International University, Nilai, 71800, Malaysia, Tel +6014 – 3034057, Email lingshing.wong@newinti.edu.my Sinouvassane Djearamane, Department of Biomedical Science, Faculty of Science, Universiti Tunku Abdul Rahman, Kampar, 31900, Perak, Malaysia, Tel +6016 – 4037685, Email biochsinouvas07@gmail.comAbstract: Streptonigrin is an aminoquinone alkaloid isolated from Streptomyces flocculus and is gaining attention as a drug molecule owing to its potential antitumor and antibiotic effects. It was previously used as an anticancer drug but has been discontinued because of its toxic effects. However, according to the most recent studies, the toxicity of streptonigrin and its structurally modified derivatives has been reduced while maintaining their potential pharmacological action at lower concentrations. To date, many investigations have been conducted on this molecule and its derivatives to determine the most effective molecule with low toxicity to enable new drug discovery. Therefore, the main objective of this study is to provide a comprehensive review and to discuss the prospects for streptonigrin and its derived compounds, which may boost the molecule as a highly interesting target molecule for new drug design, development and therapy. To complete this review, relevant literature was collected from several scientific databases, including Google Scholar, PubMed, Scopus and ScienceDirect. Following a complete screening, the obtained information is summarized in the present review to provide a good reference and accelerate the development and utilization of streptonigrin and its derivatives as pharmaceuticals.Graphical Abstract: Keywords: streptonigrin, chemistry, biosynthesis, pharmacology, anticancer, antibacterial
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- 2023
3. New 1,2-Dihydropyridine-Based Fluorophores and Their Applications as Fluorescent Probes
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Vellekkatt Jamsheena, Rakesh K. Mishra, Kollery S. Veena, Suresh Sini, Purushothaman Jayamurthy, and Ravi S. Lankalapalli
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Chemistry ,QD1-999 - Published
- 2018
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4. Expedient Synthesis of Indolo[2,3‑b]quinolines, Chromeno[2,3‑b]indoles, and 3‑Alkenyl-oxindoles from 3,3′-Diindolylmethanes and Evaluation of Their Antibiotic Activity against Methicillin-Resistant Staphylococcus aureus
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Chandrasekhar Challa, Jaice Ravindran, Mohini Mohan Konai, Sunil Varughese, Jubi Jacob, B. S. Dileep Kumar, Jayanta Haldar, and Ravi S. Lankalapalli
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Chemistry ,QD1-999 - Published
- 2017
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5. Electrospun core-shell nanofibers with encapsulated enamel matrix derivative for guided periodontal tissue regeneration
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Linda R Wang Lam, Stephen Romas, Jack G. Caton, Xinping Zhang, Ravi S. Misra, Zhuang Zhou, and Kevin Schilling
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Materials science ,Periodontal ligament stem cells ,Periodontal Ligament ,0206 medical engineering ,Nanofibers ,ALIZARIN RED ,02 engineering and technology ,Article ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Osteogenesis ,Enamel matrix derivative ,Bovine serum albumin ,Bone regeneration ,General Dentistry ,Cell Proliferation ,biology ,Cell Differentiation ,030206 dentistry ,020601 biomedical engineering ,Membrane ,chemistry ,Nanofiber ,Polycaprolactone ,Guided Tissue Regeneration, Periodontal ,Ceramics and Composites ,biology.protein ,Biomedical engineering - Abstract
The osteogenic effect of a composite electrospun core-shell nanofiber membrane encapsulated with Emdogain® (EMD) was evaluated. The membrane was developed through coaxial electrospinning using polycaprolactone as the shell and polyethylene glycol as the core. The effects of the membrane on the osteogenic differentiation of periodontal ligament stem cells (PDLSCs) were examined using Alizarin Red S staining and qRT-PCR. Characterization of the nanofiber membrane demonstrated core-shell morphology with a mean diameter of ~1 µm. Examination of the release of fluorescein isothiocyanate-conjugated bovine serum albumin (FITC-BSA) from core-shell nanofibers over a 22-day period showed improved release profile of encapsulated proteins as compared to solid nanofibers. When cultured on EMD-containing core-shell nanofibers, PDLSCs showed significantly improved osteogenic differentiation with increased Alizarin Red S staining and enhanced osteogenic gene expression, namely OCN, RUNX2, ALP, and OPN. Core-shell nanofiber membranes may improve outcomes in periodontal regenerative therapy through simultaneous mechanical barrier and controlled drug delivery function.
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- 2021
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6. Cu(I)-azidopyrrolo[3,2‑d]pyrimidine Catalyzed Glaser–Hay Reaction under Mild Conditions
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Velickakathu O. Yadhukrishnan, Arun Kumar Thangarasu, K. A. Krishnakumar, Ravi S. Lankalapalli, and Sanjay Suresh Varma
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Cultural Studies ,History ,chemistry.chemical_compound ,QD241-441 ,Literature and Literary Theory ,Pyrimidine ,Chemistry ,Hay ,Organic chemistry ,Medicinal chemistry ,Inorganic chemistry ,Catalysis ,QD146-197 - Published
- 2021
7. Tandem Photoisomerization and Transannular Cyclizations of Zerumbone Epoxide: A Model for Diversity-Oriented Synthesis Using Abundant Natural Products
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Kokkuvayil Vasu Radhakrishnan, Mohanan Biji, and Ravi S. Lankalapalli
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chemistry.chemical_compound ,Photoisomerization ,Tandem ,Chemistry ,Stereochemistry ,Organic Chemistry ,Epoxide ,Physical and Theoretical Chemistry ,Biochemistry ,Enone ,Cis–trans isomerism ,Catalysis - Abstract
Photoirradiation of (6E,9E)-zerumbone-2,3-epoxide afforded a diverse range of transannular cyclized products in the presence of a catalytic amount of Sc(OTf)3. At the behest of the geometrical isomers produced by photoirradiation, the diversity encompasses an unprecedented eudesmane core and oxo-bridged hydroxy-olefin skeletons. Structure elucidation and the stereochemical outcome of the products are described via extensive NMR analysis. The present study serves as a model for tandem photoisomerization and transannular cyclization of natural products with enone/dienone functionality.
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- 2021
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8. HJC0416 Attenuates Fibrogenesis in Activated Hepatic Stellate Cells via STAT3 and NF-κB Pathways
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Omar Nunez Lopez, Ravi S. Radhakrishnan, Yanping Gu, Xiaofu Wang, Divya Ramdas, Claire B. Cummins, Christian Sommerhalder, and Jia Zhou
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Liver Cirrhosis ,STAT3 Transcription Factor ,Drug Evaluation, Preclinical ,Thiophenes ,Article ,Cell Line ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Hepatic Stellate Cells ,Animals ,Humans ,Propidium iodide ,Cell Cycle ,NF-kappa B ,NF-κB ,Cell cycle ,Rats ,Cell biology ,IκBα ,chemistry ,030220 oncology & carcinogenesis ,Benzamides ,STAT protein ,Hepatic stellate cell ,Phosphorylation ,030211 gastroenterology & hepatology ,Surgery ,Signal transduction - Abstract
Background Hepatic fibrosis is wound-healing response that is the result of hepatic stellate cell (HSC) activation and subsequent excess extracellular matrix deposition. HSCs can be activated by a variety of inflammatory stimuli as well as through the signal transducer and activator of transcription 3 (STAT3) pathway. HJC0416 is a novel, orally bioavailable small-molecule inhibitor of STAT3 that was developed by our team using a fragment-based drug design approach. Previously, our team has shown that HJC0416 has antifibrogenic effects in activated HSCs. Recently, increasing evidence suggests that nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) plays an important role in the activation of HSCs. In the present study, we examined the role of NF-κB inhibition of HSC activation by HJC0416. Methods LX-2 (human) and HSC-T6 (rat) cell lines were used. Expression levels of extracellular proteins, NF-κB and STAT3 expression and DNA binding, and inflammatory cytokine levels were determined using western blot, ELISA, and immunofluorescence assay. Results HJC0416 decreased cell viability in a dose-dependent manner in both cell lines and arrested the cell cycle at the S phase. Increased apoptosis was seen in LX-2 cells through Yo-Pro-1 and propidium iodide immunofluorescent stating. HJC0416 significantly decreased expression of fibronectin and collagen I as well as markedly decreased α-SMA and laminin. HJC0416 inhibited the STAT3 pathway by decreasing phosphorylation of STAT3, as well as signal transduction pathway activation. Notably, HJC0416 also inhibited the classic and alternative pathways of NF-κB activation. HJC0416 inhibited LPS-induced p65 nuclear translocation and DNA binding, as well as prevented phosphorylation and degradation of inhibitory protein IκBα. HJC0416 also prevented phosphorylation of serine residue 536 on p65. Conclusions HJC0416, an inhibitor of STAT3, was found to have antifibrogenic properties in activated hepatic stellate cell lines. In addition, HJC0416 was found to inhibit the NF-κB pathway. Owing to this double effect, HJC0416 demonstrates promise for in vivo experimentation as an antifibrosis treatment.
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- 2021
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9. Effect of Mitochondrial Antioxidant (Mito-TEMPO) on Burn-Induced Cardiac Dysfunction
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Geetha L. Radhakrishnan, Kayla M. Colvill, Jake J. Wen, Taylor P. Williams, Claire B. Cummins, and Ravi S. Radhakrishnan
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Male ,Cardiac function curve ,Cardiac fibrosis ,Cardiomyopathy ,H&E stain ,Pharmacology ,Antioxidants ,03 medical and health sciences ,Organophosphorus Compounds ,0302 clinical medicine ,Piperidines ,Fibrosis ,medicine ,Animals ,Humans ,Heart Failure ,chemistry.chemical_classification ,Reactive oxygen species ,business.industry ,Myocardium ,Heart ,medicine.disease ,Mitochondria ,Rats ,Disease Models, Animal ,chemistry ,Echocardiography ,030220 oncology & carcinogenesis ,Heart failure ,030211 gastroenterology & hepatology ,Surgery ,Burns ,Reactive Oxygen Species ,business ,Injections, Intraperitoneal ,Mitochondrial DNA replication - Abstract
Background Imbalance of oxidants/antioxidants results in heart failure, contributing to mortality after burn injury. Cardiac mitochondria are a prime source of reactive oxygen species (ROS), and a mitochondrial-specific antioxidant may improve burn-induced cardiomyopathy. We hypothesize that the mitochondrial-specific antioxidant, Triphenylphosphonium chloride (Mito-TEMPO), could protect cardiac function after burn. Study design Male rats had a 60% total body surface area (TBSA) scald burn injury and were treated with/without Mito-TEMPO (7 mg/kg-1, intraperitoneal) and harvested at 24 hours post-burn. Echocardiography (ECHO) was used for measurement of heart function. Masson Trichrome and hematoxylin and eosin (H & E) staining were used for cardiac fibrosis and immune response. Qualitative polymerase chain reaction (qPCR) was used for mitochondrial DNA replication and gene expression. Results Burn-induced cardiac dysfunction, fibrosis, and mitochondrial damage were assessed by measurement of mitochondrial function, DNA replication, and DNA-encoded electron transport chain-related gene expression. Mito-TEMPO partially improved the abnormal parameters. Burn-induced cardiac dysfunction was associated with crosstalk between the NFE2L2-ARE pathway, PDE5A-PKG pathway, PARP1-POLG-mtDNA replication pathway, and mitochondrial SIRT signaling. Conclusions Mito-TEMPO reversed burn-induced cardiac dysfunction by rescuing cardiac mitochondrial dysfunction. Mitochondria-targeted antioxidants may be an effective therapy for burn-induced cardiac dysfunction.
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- 2021
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10. Metabolic changes in pomegranate fruit skin following cold storage promote chilling injury of the peel
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Ravi S. Baghel, Alexandra Keren-Keiserman, and Idit Ginzberg
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0106 biological sciences ,Molecular biology ,Physiology ,Cuticle ,Science ,Cold storage ,Biology ,01 natural sciences ,Antioxidants ,Pomegranate ,Article ,040501 horticulture ,chemistry.chemical_compound ,Phenols ,Gene Expression Regulation, Plant ,Browning ,Chilling injury ,Punicalagin ,Plant Proteins ,Multidisciplinary ,Superoxide Dismutase ,food and beverages ,04 agricultural and veterinary sciences ,Catalase ,Horticulture ,Antioxidant capacity ,Glutathione Reductase ,chemistry ,Food Storage ,Fruit ,Medicine ,0405 other agricultural sciences ,Plant sciences ,010606 plant biology & botany - Abstract
Pomegranate cv. ‘Wonderful’ fruit are susceptible to chilling injuries of the peel (CIp) when stored at 7 °C in modified-atmosphere bags for more than 3 months. The damage, manifested as superficial browning, is restricted to the fruit skin, i.e., the outer colored layer of the peel. To characterize possible causes of CIp development, fruit were collected at early harvest—when the premature fruit are poorly colored and susceptible to CIp development, and at late harvest—when mature fruit have fully red skin and less susceptibility to CIp. Skin samples were collected on day of harvest and at different time points during storage. Anatomical study of skin with CIp disorder showed a broken cuticle layer with underlying degenerated cells. A high total phenol content, which is associated with high antioxidant capacity, was not sufficient to prevent the development of CIp in the premature fruit. The concentration of punicalagin was the same for premature and mature skin at harvest and during storage, and therefore not associated with CIp development in the premature fruit skin. Furthermore, the expression of antioxidant-related genes CAT2, SOD and GR2 was similar for both premature and mature fruit skin. Poor pigmentation of the premature fruit skin and chilling-induced downregulation of key anthocyanin-biosynthesis genes were associated with CIp development. High total phenol concentration combined with high expression of the gene encoding PPO was also associated with CIp; however, high expression ratio of PAL to PPO was found in mature skin, and may be associated with reduced CIp disorder. The results presented suggest future possibilities for controlling the CIp phenomenon.
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- 2021
11. Multivariate Analysis of Water Quality of Ganga River
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Nonita Sharma, Ravi S Sharma, Kuldeep Kumar, and Piyush Bagla
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Biochemical oxygen demand ,Hydrology ,geography ,education.field_of_study ,geography.geographical_feature_category ,Multivariate analysis ,General Computer Science ,020209 energy ,020208 electrical & electronic engineering ,Population ,Drainage basin ,Effective management ,02 engineering and technology ,Fecal coliform ,chemistry.chemical_compound ,fluids and secretions ,Nitrate ,chemistry ,0202 electrical engineering, electronic engineering, information engineering ,Environmental science ,Water quality ,Electrical and Electronic Engineering ,education - Abstract
With an increase in population and accelerated pace of industrialization, water quality is going to degrade day-by-day. The main source of water in India is from rivers. The Ganga River Basin is the world’s most populated and is home to half of India's population, including two-thirds of the nation’s poor. This paper highlights the utility of multivariate statistical techniques for evaluating, interpreting complex data sets and recognizing spatial differences in water quality for effective management of river water quality. A study was conducted to check the water quality in three different states of India, namely Bihar, Uttar Pradesh and West Bengal, by examining their various Physico-chemical parameters. These parameters were analyzed, and values obtained were compared with standard values. We have examined the causality relationship and correlation existence between Temp, pH, Dissolved Oxygen, Conductivity, Biochemical Oxygen Demand, Nitrate, Total Coliform and Fecal Coliform. Total Coliform and Fecal Coliform are strongly correlated with a value of 0.975, whereas Dissolved Oxygen and temperature have a negative correlation with a − 0.650 value. The analysis also reveals that Biochemical Oxygen Demand, Fecal Coliform and Total Coliform parameters impact the most in the degradation of water quality of the Ganga river water.
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- 2021
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12. Morpholinium bisulfate [morH][HSO4]: An efficient and reusable catalyst for the synthesis of bis(indolyl)methanes
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Ravi S. Balaskar, Bapurao B. Shingate, Murlidhar S. Shingare, and Dhananjay V. Mane
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Morpholinium bisulfate [morH][HSO4] ,Bis(indolyl)methanes ,Reusability ,Grinding ,Chemistry ,QD1-999 - Abstract
Morpholinium bisulfate [morH][HSO4] ionic liquid was found to be an effective catalyst for the condensation reaction of indoles with carbonyl compound at room temperature. Present methodology has several merits such as mild reaction condition, inexpensive catalyst, stable at room temperature and it was also found that this catalyst could be recovered quantitatively and reused without much loss of catalytic activity.
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- 2016
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13. Glycosylation as a tool for rational vaccine design
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Vivek Hariharan and Ravi S. Kane
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0106 biological sciences ,0301 basic medicine ,Glycan ,Glycosylation ,Bioengineering ,Computational biology ,Biology ,Antibodies, Viral ,01 natural sciences ,Applied Microbiology and Biotechnology ,Epitope ,Mice ,03 medical and health sciences ,chemistry.chemical_compound ,Immune system ,Antigen ,010608 biotechnology ,Animals ,Humans ,Viral Vaccines ,Antibodies, Neutralizing ,Immune surveillance ,carbohydrates (lipids) ,030104 developmental biology ,Carbohydrate Sequence ,chemistry ,Research Design ,biology.protein ,Antibody ,Surface protein ,Biotechnology - Abstract
The discovery of broadly neutralizing antibodies that can neutralize multiple strains or subtypes of a pathogen has renewed interest in the development of broadly protective vaccines. To that end, there has been an interest in designing immunofocusing strategies to direct the immune response to specific, conserved regions on antigenic proteins. Modulation of glycosylation is one such immunofocusing strategy; extensive glycosylation is often exploited by pathogens for immune evasion. Masking epitopes on protein immunogens with "self" glycans can also shield the underlying protein surface from humoral immune surveillance. We review recent advances in applying glycosylation as an immunofocusing tool. We also highlight recent interesting work in the HIV-1 field involving the identification and elicitation of broadly neutralizing antibodies that incorporate glycans into their binding epitopes.
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- 2020
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14. Modulating Heparanase Activity: Tuning Sulfation Pattern and Glycosidic Linkage of Oligosaccharides
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Zhenfeng Song, Israel Vlodavsky, Sanyong Zhu, Kezhong Zhang, Ravi S. Loka, Hien M. Nguyen, and Jiayi Li
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Anomer ,Oligosaccharides ,CHO Cells ,Cleavage (embryo) ,01 natural sciences ,Article ,Mice ,03 medical and health sciences ,chemistry.chemical_compound ,Cricetulus ,Sulfation ,Cricetinae ,Drug Discovery ,Animals ,Humans ,Heparanase ,Glycosides ,Glucuronidase ,030304 developmental biology ,chemistry.chemical_classification ,0303 health sciences ,Dose-Response Relationship, Drug ,biology ,Heparin ,Substrate (chemistry) ,Glycosidic bond ,Heparan sulfate ,biology.organism_classification ,0104 chemical sciences ,Enzyme Activation ,Molecular Docking Simulation ,010404 medicinal & biomolecular chemistry ,chemistry ,Biochemistry ,Molecular Medicine ,Heparitin Sulfate - Abstract
Heparanase cleaves polymeric heparan sulfate (HS) molecules into smaller oligosaccharides, allowing for release of angiogenic growth factors promoting tumor development and autoreactive immune cells to reach the insulin-producing β cells. Interaction of heparanase with HS chains is regulated by specific substrate sulfation sequences. We have synthesized eleven trisaccharides that are highly tunable in structure and sulfation pattern, allowing us to determine how heparanase recognizes HS substrate and selects a favorable cleavage site. Our study shows that (1) N-SO(3)(−) at +1 subsite and 6-O-SO(3)(−) at −2 subsite of trisaccharides are critical for heparanase recognition; (2) addition of 2-O-SO(3)(−) at the −1 subsite and of 3-O-SO(3)(−) to GlcN unit is not advantageous; and (3) the anomeric configuration (α or β) at the reducing end is crucial in controlling heparanase activity. Our study also illustrates that the α-trisaccharide having N- and 6-O-SO(3)(−) at −2 and +1 subsites inhibited heparanase and was resistant toward hydrolysis.
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- 2020
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15. Synthesis of 2, 5‐Diamino‐ p— benzoquinones via Aerobic Oxidative C(sp 2 )‐C(sp 2 ) Bond Cleavage and Mechanistic Studies
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Cherumuttathu H. Suresh, Subhadra Suma, Ravi S. Lankalapalli, Jaice Ravindran, and Anandavally Asha
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Stereochemistry ,Chemistry ,P-Benzoquinones ,General Chemistry ,Oxidative phosphorylation ,Bond cleavage - Published
- 2020
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16. Distinct regulation of bioenergetics and translation by group I mGluR and NMDAR
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Ravi S. Muddashetty, Sudhriti Ghosh Dastidar, Aditi Bhattacharya, Sumantra Chattarji, Sumita Chakraborty, and Shreya Das Sharma
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Bioenergetics ,Stimulation ,EEF2 ,Biochemistry ,Receptors, N-Methyl-D-Aspartate ,03 medical and health sciences ,0302 clinical medicine ,AMP-activated protein kinase ,Peptide Elongation Factor 2 ,mental disorders ,Genetics ,Phosphorylation ,Molecular Biology ,030304 developmental biology ,0303 health sciences ,biology ,Chemistry ,musculoskeletal, neural, and ocular physiology ,Glutamate receptor ,AMPK ,Translation (biology) ,Articles ,Cell biology ,nervous system ,Metabotropic glutamate receptor ,Synapses ,biology.protein ,NMDA receptor ,Corrigendum ,Energy Metabolism ,030217 neurology & neurosurgery - Abstract
Neuronal activity is responsible for large energy consumption within the brain. However, the cellular mechanisms draining ATP upon the arrival of a stimulus are yet to be explored systematically at the post-synapse. Here we provide evidence that a significant fraction of ATP is consumed upon glutamate stimulation to energize the mGluR-induced protein synthesis. We find that both mGluR and NMDAR alter protein synthesis and ATP consumption with distinct kinetics at the synaptic-dendritic compartments. While mGluR activation leads to a rapid and sustained reduction in the neuronal ATP level, NMDAR activation has no immediate impact on the same. ATP consumption correlates inversely to the kinetics of protein synthesis for both the receptors. We observe a persistent elevation in protein synthesis within 5 minutes of mGluR activation and robust inhibition of the same within 2 minutes of NMDAR activation, assessed by the phosphorylation status of eEF2 and metabolic labeling. However, a delayed protein synthesis-dependent ATP expenditure ensues after 15 minutes of NMDAR activation. We identify a central role for AMPK in this correlation between protein synthesis and ATP consumption. AMPK is dephosphorylated and inhibited upon mGluR activation while it was rapidly phosphorylated upon NMDAR activation. Perturbing AMPK activity disrupts the receptor-specific modulations of eEF2 phosphorylation and protein synthesis. Therefore, our observations suggest that the glutamate receptors required modulating the AMPK-eEF2 signaling axis to alter neuronal protein synthesis and bioenergetics.Short SummaryStimulation of glutamate receptors induces robust protein synthesis within cortical neurons and consumes a significantly large fraction of cellular ATP. Glutamate receptors viz. mGlulR and NMDAR modulate AMPK-eEF2 signaling uniquely leading to the dynamic regulation of protein synthesis and bioenergetics.Key HighlightsProtein synthesis following glutamate receptor activation is responsible for the bulk of the activity-induced ATP consumption in cortical neurons.mGluR and NMDAR regulate protein synthesis with distinct kinetics and dictate the subsequent impacts over neuronal ATP level.Dynamic modulation of AMPK and eEF2 phosphorylation is key to create unique temporal features of receptor-specific protein synthesis and bioenergetics.
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- 2022
17. An insight into the impact of triazophos and deltamethrin pesticides as individual and in combination on oxidative stress and histopathological alterations inEudrilus eugeniae
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Ravi S. Pandey, R.K. Tiwari, and Shikha Singh
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021110 strategic, defence & security studies ,Ecology ,biology ,0211 other engineering and technologies ,02 engineering and technology ,010501 environmental sciences ,Pesticide ,biology.organism_classification ,medicine.disease_cause ,01 natural sciences ,Toxicology ,chemistry.chemical_compound ,Eudrilus eugeniae ,Deltamethrin ,chemistry ,medicine ,General Earth and Planetary Sciences ,Ecology, Evolution, Behavior and Systematics ,Oxidative stress ,0105 earth and related environmental sciences ,General Environmental Science - Abstract
The application of a mixture of pesticides to the agricultural field may adversely affect the health of non-target organisms besides the target ones. In the present study, the antagonistic effect o...
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- 2019
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18. Preclinical evaluation of binimetinib (MEK162) delivered via polymeric nanocarriers in combination with radiation and temozolomide in glioma
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Peter Sminia, Robin M. de Kruijff, Helga E. de Vries, Gabriel Becerril Aragon, Ravi S. Narayan, Susanne M A van der Pol, Guzman Torrelo Villa, Ana Gasol Garcia, Fatima Bikhezar, Ben J. Slotman, Astrid J.G.M. van der Meer, Antonia G. Denkova, Molecular cell biology and Immunology, Radiation Oncology, Amsterdam Neuroscience - Neurovascular Disorders, CCA - Cancer biology and immunology, and ACS - Microcirculation
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0301 basic medicine ,MAPK/ERK pathway ,Cancer Research ,Polymers ,Drug Evaluation, Preclinical ,Blood–brain barrier ,Binimetinib ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Polymeric nanocarriers ,Glioma ,Spheroids, Cellular ,medicine ,Temozolomide ,Tumor Cells, Cultured ,Humans ,Antineoplastic Agents, Alkylating ,Cell Proliferation ,Drug Carriers ,Radiation ,Brain Neoplasms ,Spheroid ,Chemoradiotherapy ,medicine.disease ,030104 developmental biology ,medicine.anatomical_structure ,Neurology ,Oncology ,chemistry ,Blood-Brain Barrier ,030220 oncology & carcinogenesis ,Polymersome ,embryonic structures ,Cancer research ,Laboratory Investigation ,Nanoparticles ,Benzimidazoles ,Drug Therapy, Combination ,Neurology (clinical) ,Nanocarriers ,Glioblastoma ,medicine.drug ,Signal Transduction - Abstract
Background and purpose Glioblastoma multiforme (GBM) is the most aggressive subtype of malignant gliomas, with an average survival rate of 15 months after diagnosis. More than 90% of all GBMs have activating mutations in the MAPK/ERK pathway. Recently, we showed the allosteric MEK1/2 inhibitor binimetinib (MEK162) to inhibit cell proliferation and to enhance the effect of radiation in preclinical human GBM models. Because the free drug cannot pass the blood–brain barrier (BBB), we investigated the use of nanocarriers for transport of the drug through the BBB and its efficacy when combined with radiotherapy and temozolomide (TMZ) in glioma spheroids. Methods In vitro studies were performed using multicellular U87 human GBM spheroids. Polymeric nanocarriers (polymersomes) were loaded with MEK162. The interaction between nanocarrier delivered MEK162, irradiation and TMZ was studied on the kinetics of spheroid growth and on protein expression in the MAPK/ERK pathway. BBB passaging was evaluated in a transwell system with human cerebral microvascular endothelial (hCMEC/D3) cells. Results MEK162 loaded polymersomes inhibited spheroid growth. A synergistic effect was found in combination with fractionated irradiation and an additive effect with TMZ on spheroid volume reduction. Fluorescent labeled polymersomes were taken up by human cerebral microvascular endothelial cells and passed the BBB in vitro. Conclusion MEK162 loaded polymersomes are taken up by multicellular spheroids. The nanocarrier delivered drug reduced spheroid growth and inhibited its molecular target. MEK162 delivered via polymersomes showed interaction with irradiation and TMZ. The polymersomes crossed the in vitro BBB model and therewith offer exciting challenges ahead for delivery of therapeutics agents to brain tumours.
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- 2019
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19. Synthesis and Characterization of Mannich Bases of Imidazo[2,1-b][1,3,4]Thiadiazoles
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Ravi S. Naik
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Thiadiazoles ,Chemistry ,Combinatorial chemistry - Published
- 2021
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20. Function of FMRP domains in regulating distinct roles of neuronal protein synthesis
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Sreenath Ravindran, Ravi S Muddashetty, Bindushree K Radhakrishna, Sarayu Ramakrishna, Michelle Ninochka D'Souza, Dasaradhi Palakodeti, Lahari Yeramala, and Vishwaja Jhaveri
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congenital, hereditary, and neonatal diseases and abnormalities ,Microtubule ,Chemistry ,Polysome ,Translational regulation ,Phosphorylation ,RNA-binding protein ,Translation (biology) ,Ribosome ,Function (biology) ,nervous system diseases ,Cell biology - Abstract
The Fragile X Mental Retardation Protein (FMRP) is an RNA Binding Protein that regulates translation of mRNAs, essential for synaptic development and plasticity. FMRP interacts with a specific set of mRNAs and aids in their microtubule dependent transport and regulates their translation through its association with ribosomes. However, the biochemical role of individual domains of FMRP in forming neuronal granules and associating with microtubules and ribosomes is currently undefined. Here, we report that the C-terminus domain of FMRP is sufficient to bind to ribosomes as well as polysomes akin to the full-length protein. Furthermore, the C-terminus domain alone is essential and responsible for FMRP-mediated translation repression in neurons. However, FMRP-mediated puncta formation and microtubule association is favored by the synergistic combination of FMRP domains and not by individual domains. Interestingly, we show that the phosphorylation of hFMRP at Serine-500 is important in modulating the dynamics of translation by controlling ribosome/polysome association. This is a fundamental mechanism governing the size and number of FMRP puncta, which appear to contain actively translating ribosomes. Finally through the use of pathogenic mutations, we emphasize the hierarchy of the domains of FMRP in their contribution to translation regulation.
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- 2021
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21. Transition Metal/Lewis Acid Catalyzed Reactions of Zerumbone for Diverse Molecular Motifs
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Mohanan Biji, Kokkuvayil Vasu Radhakrishnan, Ravi S. Lankalapalli, and B. Prabha
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Addition reaction ,Natural product ,Humulene ,biology ,Chemistry ,Stereochemistry ,General Chemical Engineering ,Synthon ,Epoxide ,General Chemistry ,Sesquiterpene ,biology.organism_classification ,Biochemistry ,Catalysis ,chemistry.chemical_compound ,Zingiber zerumbet ,Zingiberaceae ,Materials Chemistry ,Lewis acids and bases ,Sesquiterpenes ,Lewis Acids - Abstract
Zerumbone is a naturally occurring humulene type sesquiterpene, isolated from the rhizomes of Zingiber zerumbet (L.) Smith with excellent therapeutic potential and is recognized as a valuable synthon for the construction of diverse array of natural product motifs. In this review, we intended to highlight our achievements in utilizing abundant natural product zerumbone and its derivatives for the development of pharmacologically relevant molecular scaffolds. We provided an account of the transition-metal catalyzed 1,4-conjugate addition reactions of zerumbone and its derivatives along with palladium-catalyzed cross-couplings, transition metal-based Lewis acid promoted interrupted Nazarov cyclisation reaction with substituted indoles and transannular cyclizations, photo-induced transformations of zerumbone and its epoxide.
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- 2021
22. Fertilizer industry effluent induced hematological, histopathological and biochemical alterations in a stinging catfish, Heteropneustes fossilis (Bloch, 1794)
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Ravi S. Pandey and Upma Singh
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Mean corpuscular hemoglobin ,Histopathology ,Environmental pollution ,Management, Monitoring, Policy and Law ,Environmental Science (miscellaneous) ,Heteropneustes fossilis ,Lipid peroxidation ,Superoxide dismutase ,chemistry.chemical_compound ,medicine ,GE1-350 ,Food science ,Mean corpuscular volume ,Ecology, Evolution, Behavior and Systematics ,Mean corpuscular hemoglobin concentration ,medicine.diagnostic_test ,biology ,Fertilizer industry effluent ,Anti-Oxidative enzyme ,biology.organism_classification ,Agricultural and Biological Sciences (miscellaneous) ,Environmental sciences ,chemistry ,Catalase ,Oxidative stress ,biology.protein ,Haematology - Abstract
Industrial effluents reaching to the aquatic ecosystem is one of the major causes of environmental pollution. Heteropneustes fossilis, one of the most common edible fish if exposed to industrial effluents containing harmful substances may be a serious threat to human health. Therefore, the present study aimed to study the impact of fertilizer industry effluent on H. fossilis. Fish were exposed to treated and untreated fertilizer industry effluent (LC50 = 2.35% v/v) for 96 h along with a proper control. The physico-chemical parameters such as turbidity, biological oxygen demand (BOD) and chemical oxygen demand (COD) of both treated and untreated fertilizer industry effluent were also analyzed as these parameters were not in range as per guidelines. Hematological parameters such as Red Blood cells (RBC), Haemoglobin (% Hb), Mean corpuscular volume (MCV), Mean Corpuscular Hemoglobin (MCH) and Mean Corpuscular Hemoglobin Concentration (MCHC) showed significant decrease while there was sharp increase in differential leucocyte count (DLC) especially the neutrophil count. Distinct alteration in the architecture of gills, liver and kidney was observed besides significant increase in the level of lipid peroxidation (LPO), alanine aminotransferase (ALT), aspartate aminotransferase (AST), acid phosphatases (ACP) and alkaline phosphatase (ALP) while the level of superoxide dismutase (SOD), catalase (CAT), glutathione s-transferase (GST) and reduced glutathione (GSH) activity decreased in metabolically active tissues like brain, liver, kidney, gills and muscles. The results indicate that industrial effluent has potent oxidative stress inducers on one hand and histoarchitectural and physiological altering contaminants on the other. This condition may adversely affect the health of aquatic organisms, the fish and ultimately the human beings.
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- 2021
23. Application of a microalga, Scenedesmus obliquus PF3, for the biological removal of nitric oxide (NO) and carbon dioxide
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Yanling Yu, Da Li, Shanshan Ma, Ravi S. Yadav, Yujie Feng, and Dianlin Li
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Flue gas ,Denitrification ,010504 meteorology & atmospheric sciences ,Health, Toxicology and Mutagenesis ,chemistry.chemical_element ,Biomass ,010501 environmental sciences ,Nitric Oxide ,Toxicology ,01 natural sciences ,Carbon Cycle ,chemistry.chemical_compound ,Air Pollution ,Microalgae ,NOx ,0105 earth and related environmental sciences ,Air Pollutants ,Carbon fixation ,General Medicine ,Carbon Dioxide ,Adaptation, Physiological ,Pollution ,Nitrogen ,Biodegradation, Environmental ,chemistry ,Environmental chemistry ,Carbon dioxide ,Nitrogen oxide ,Scenedesmus - Abstract
Nitrogen oxide (NOx) emissions from flue gas lead to a series of environmental problems. Biological removal of Nitrogen oxide (NOx) from flue gas by microalgae is a potential approach for reducing the problems caused by these emissions. However, few microalgal strains are reported to remove NOx from flue gas. Here, a microalga strain PF3 (identified as Scenedesmus obliquus), which can remove NOx and fix CO2 from flue gas is isolated. The tolerance of Scenedesmus obliquus PF3 to CO2, NO, SO2 and its adaptabilities to environmental factors (pH and temperature), and its performance in the removal of NO and CO2 are investigated. Scenedesmus obliquus PF3 showed biomass accumulation when sparged with 15% CO2 or 500 ppm NO or 50 ppm SO2, and bisulfite less than 2 mM showed no toxicity to Scenedesmus obliquus PF3. Additionally, PF3 grew well in a wide range of pH and temperatures from 4.5 to 10.5 and 15 °C–30 °C, respectively. When sparged with simulated flue gas (100 ppm NO, 10% CO2, (N2 as balance gas)), the microalgae culture system removed NO and CO2 at a rate of 2.86 ± 0.23 mg L−1 d−1 and 1.48 ± 0.12 g L−1 d−1, respectively, where up to 96.9 ± 0.03% (2.77 ± 0.08 mg L−1 d−1) and 87.7 ± 6.22% (1.29 ± 0.01 mg L−1 d−1) of the removed NO and CO2, respectively, were assimilated in algal biomass. These results suggest that Scenedesmus obliquus PF3 is a promising candidate for NOx removal and carbon fixation of flue gas.
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- 2019
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24. Plasmonic Gold Nanoprism–Cobalt Molecular Complex Dyad Mimics Photosystem-II for Visible–NIR Illuminated Neutral Water Oxidation
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Shikha Khandelwal, Saumyakanti Khatua, Gayatri K. Joshi, Piue Ghosh, Arnab Dutta, Ashish Kar, Ravi S. Hegde, and Ab Qayoom Mir
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Materials science ,Photosystem II ,Renewable Energy, Sustainability and the Environment ,Energy Engineering and Power Technology ,chemistry.chemical_element ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Photochemistry ,01 natural sciences ,0104 chemical sciences ,Fuel Technology ,chemistry ,Chemistry (miscellaneous) ,Covalent bond ,Materials Chemistry ,0210 nano-technology ,Cobalt ,Photocatalytic water splitting ,Plasmon - Abstract
Constructing an artificial assembly for efficient photocatalytic water splitting is key in the pursuit for a solar-driven renewable energy economy. Here, we have fabricated a covalently linked gold...
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- 2019
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25. Endothelial PAI-1 (Plasminogen Activator Inhibitor-1) Blocks the Intrinsic Pathway of Coagulation, Inducing the Clearance and Degradation of FXIa (Activated Factor XI)
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David Gailani, Cristina Puy, Andras Gruber, Matthew W. Hagen, Anh T. P. Ngo, Owen J. T. McCarty, Monica T. Hinds, Jiaqing Pang, Florea Lupu, and Ravi S. Keshari
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0301 basic medicine ,Endothelium ,030204 cardiovascular system & hematology ,Pharmacology ,Factor XIa ,Article ,Fibrin ,03 medical and health sciences ,chemistry.chemical_compound ,Papio ursinus ,0302 clinical medicine ,Thrombin ,Plasminogen Activator Inhibitor 1 ,medicine ,Animals ,Humans ,Platelet activation ,Blood Coagulation ,biology ,Chemistry ,Endothelial Cells ,Kallikrein ,Blot ,030104 developmental biology ,medicine.anatomical_structure ,Plasminogen activator inhibitor-1 ,biology.protein ,Cardiology and Cardiovascular Medicine ,Plasminogen activator ,medicine.drug - Abstract
Objective— Activation of coagulation FXI (factor XI) by FXIIa (activated factor XII) is a prothrombotic process. The endothelium is known to play an antithrombotic role by limiting thrombin generation and platelet activation. It is unknown whether the antithrombotic role of the endothelium includes sequestration of FXIa (activated factor XI) activity. This study aims to determine the role of endothelial cells (ECs) in the regulation of the intrinsic pathway of coagulation. Approach and Results— Using a chromogenic assay, we observed that human umbilical veins ECs selectively blocked FXIa yet supported kallikrein and FXIIa activity. Western blotting and mass spectrometry analyses revealed that FXIa formed a complex with endothelial PAI-1 (plasminogen activator inhibitor-1). Blocking endothelial PAI-1 increased the cleavage of a chromogenic substrate by FXIa and the capacity of FXIa to promote fibrin formation in plasma. Western blot and immunofluorescence analyses showed that FXIa–PAI-1 complexes were either released into the media or trafficked to the early and late endosomes and lysosomes of ECs. When baboons were challenged with Staphylococcus aureus to induce a prothrombotic phenotype, an increase in circulating FXIa–PAI-1 complex levels was detected by ELISA within 2 to 8 hours postchallenge. Conclusions— PAI-1 forms a complex with FXIa on ECs, blocking its activity and inducing the clearance and degradation of FXIa. Circulating FXIa–PAI-1 complexes were detected in a baboon model of S. aureus sepsis. Although ECs support kallikrein and FXIIa activity, inhibition of FXIa by ECs may promote the clearance of intravascular FXIa. Visual Overview— An online visual overview is available for this article.
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- 2019
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26. Evaluation and in vivo efficacy study of pyrano[3,2‐c]quinoline analogues as TNF‐α inhibitors
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Anamik Shah, Narsinh Dodia, Ravi S. Chaniara, Kuldip D Upadhyay, and Rupesh C. Khunt
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Xylazine ,Inflammation ,Pharmacology ,01 natural sciences ,Biochemistry ,Rats, Sprague-Dawley ,Mice ,chemistry.chemical_compound ,NF-KappaB Inhibitor alpha ,In vivo ,Nitriles ,Drug Discovery ,medicine ,Animals ,Humans ,Phosphorylation ,Mice, Inbred BALB C ,U937 cell ,Tumor Necrosis Factor-alpha ,010405 organic chemistry ,Chemistry ,Organic Chemistry ,Quinoline ,Phosphodiesterase ,U937 Cells ,Cyclic Nucleotide Phosphodiesterases, Type 4 ,Rats ,0104 chemical sciences ,010404 medicinal & biomolecular chemistry ,IκBα ,Proteolysis ,Quinolines ,Salbutamol ,Molecular Medicine ,Ketamine ,Tumor Necrosis Factor Inhibitors ,Tumor necrosis factor alpha ,Phosphodiesterase 4 Inhibitors ,medicine.symptom ,medicine.drug - Abstract
A series of pyrano[3,2 c]quinoline was evaluated for its in vivo efficacy as TNF-α inhibitor using LPS, phosphodiesterase (PDE)-4, and CIA assays in different mice/rat models. The synthesis was performed using one-pot multicomponent condensation between 2,4-dihydroxy-1-methylquinoline, malononitrile, and diverse un(substituted) aromatic aldehydes. In vivo efficacy of the title compounds was evaluated using LPS assay in BALB/c mice, PDE4 inhibition in ketamine-xylazine-induced anesthetize SD rats, and CIA assay was performed in DBA/1J mice as per the standard literature protocols. The outcome of the study revealed that compound 4v was found to be most promising candidate of the series. It was efficacious with 48.8 ± 13.0% inhibition of TNF-α release at 100 mg/kg p.o., in the LPS assay in Balb/c mice model. It was effective in PDE4 assay in ketamine-xylazine-induced anesthetize SD rats with duration of 38.3 ± 4.5 min for reversal of anesthetic effect and also showed significant inhibition of PDE4 in salbutamol treated U937 cell assay. It was also abolished TNF-α induced phosphorylation and degradation of IκBα. Ultimately, its effect on CIA-related bone and cartilage damage was found statistically similar to Enbrel.
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- 2019
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27. Enzymatic basis for C‐lignin monomer biosynthesis in the seed coat of Cleome hassleriana
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Xiaoqiang Wang, Richard A. Dixon, Rajeev K. Azad, Xiaolan Rao, Aaron Harkelroad, Fang Chen, Xirong Xiao, Chunliu Zhuo, and Ravi S. Pandey
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Models, Molecular ,0106 biological sciences ,0301 basic medicine ,Cleome hassleriana ,Protein Conformation ,Cinnamyl-alcohol dehydrogenase ,macromolecular substances ,Plant Science ,Biology ,Lignin ,complex mixtures ,01 natural sciences ,Substrate Specificity ,03 medical and health sciences ,chemistry.chemical_compound ,Biosynthesis ,Gene Expression Regulation, Plant ,Genetics ,Caffeic acid ,Methionine synthase ,Phylogeny ,Plant Proteins ,Gene Expression Profiling ,fungi ,technology, industry, and agriculture ,Gene Expression Regulation, Developmental ,food and beverages ,Methyltransferases ,Cell Biology ,biology.organism_classification ,Cleome ,O-methyltransferase ,Biosynthetic Pathways ,Alcohol Oxidoreductases ,Kinetics ,030104 developmental biology ,chemistry ,Biochemistry ,Seeds ,biology.protein ,010606 plant biology & botany - Abstract
C-lignin is a linear polymer of caffeyl alcohol, found in the seed coats of several exotic plant species, with promising properties for generation of carbon fibers and high value chemicals. In the ornamental plant Cleome hassleriana, guaiacyl (G) lignin is deposited in the seed coat for the first 6-12 days after pollination, after which G-lignin deposition ceases and C-lignin accumulates, providing an excellent model system to study C-lignin biosynthesis. We performed RNA sequencing of seed coats harvested at 2-day intervals throughout development. Bioinformatic analysis identified a complete set of lignin biosynthesis genes for Cleome. Transcript analysis coupled with kinetic analysis of recombinant enzymes in Escherichia coli revealed that the switch to C-lignin formation was accompanied by down-regulation of transcripts encoding functional caffeoyl CoA- and caffeic acid 3-O-methyltransferases (CCoAOMT and COMT) and a form of cinnamyl alcohol dehydrogenase (ChCAD4) with preference for coniferaldehyde as substrate, and up-regulation of a form of CAD (ChCAD5) with preference for caffealdehyde. Based on these analyses, blockage of lignin monomer methylation by down-regulation of both O-methyltransferases (OMTs) and methionine synthase (for provision of C1 units) appears to be the major factor in diversion of flux to C-lignin in the Cleome seed coat, although the change in CAD specificity also contributes based on the reduction of C-lignin levels in transgenic Cleome with down-regulation of ChCAD5. Structure modeling and mutational analysis identified amino acid residues important for the preference of ChCAD5 for caffealdehyde.
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- 2019
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28. Acute toxicity evaluation of triazophos, deltamethrin and their combination on earthworm,Eudrilus eugeniaeand its impact on AChE activity
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Shikha Singh, R.K. Tiwari, and Ravi S. Pandey
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Aché ,0211 other engineering and technologies ,02 engineering and technology ,010501 environmental sciences ,01 natural sciences ,Toxicology ,chemistry.chemical_compound ,Eudrilus eugeniae ,parasitic diseases ,Ecology, Evolution, Behavior and Systematics ,0105 earth and related environmental sciences ,General Environmental Science ,021110 strategic, defence & security studies ,Pyrethroid ,Ecology ,biology ,Earthworm ,Organophosphate ,Pesticide ,biology.organism_classification ,Acute toxicity ,language.human_language ,Deltamethrin ,chemistry ,language ,General Earth and Planetary Sciences - Abstract
The acute toxicity of three formula grade pesticides namely, triazophos (an organophosphate, OP), deltamethrin (a pyrethroid) and combined pesticide (triazophos + deltamethrin) was determined in ea...
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- 2019
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29. STUDY ON THE CHEMICAL CONSTITUENTS OF THE ESSENTIAL OIL FROM NYCTANTHES ARBOR-TRISTIS AND ITS MOLECULAR DOCKING STUDIES
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Venkatareddy G, Ravi S, Dharani J, and Karthick
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Pharmacology ,Traditional medicine ,Nyctanthes arbor-tristis ,Chemistry ,law ,Chemical constituents ,fungi ,Pharmaceutical Science ,Pharmacology (medical) ,Essential oil ,law.invention - Abstract
Objectives: The objectives of this study were to determine the chemical composition of the essential oil obtained from the flowers of Nyctanthes arbor-tristis (NAT) and to carryout molecular docking studies against three bacterial proteins to study the mechanism of the antibacterial activity. Methods: The essential oil was obtained from the flowers of NAT by hydrodistillation and the chemical composition was determined by gas chromatography–mass spectrometry analysis. Docking study was carried out for 14 compounds identified from NAT against three bacterial proteins 1UAG, 3TYE, and 3UDI. Results: Fourteen compounds were identified in the essential oil. 1-octanol (74.81%) is the predominant compound followed by phytol (6.80%), bis (2-ethylhexyl) phthalate (5.88%), and eucarvone (4.23%). Many compounds are similar to that of the essential oil from jasmine. Among the 14 compounds identified, 7,9-di-tert-butyl-1-oxaspiro (4,5) deca-6,9-diene-2,8-dione interacted well with 1UAG and 3TYE and showed binding scores of −8.9 and −7.2 K Cal/mol, respectively, involving hydrophilic and hydrophobic interactions. With the protein 3UDI, the compound eucarvone exhibited a binding score of −7.1 K Cal/mol. Conclusion: The similarities between the essential oil constituents of flowers the two plants NAT and jasmine. Therefore, it could be concluded that NAT flowers of Coimbatore are a good source of fragrance for cosmetic industry and as an antibacterial agent.
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- 2019
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30. Roles of magnetic particles in magnetic seeding coagulation-flocculation process for surface water treatment
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Junfeng Liu, Yujie Feng, Jiayue Zeng, Muchen Sun, Zhaohan Zhang, Miao Lv, and Ravi S. Yadav
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congenital, hereditary, and neonatal diseases and abnormalities ,Flocculation ,Chemistry ,Sedimentation (water treatment) ,Filtration and Separation ,02 engineering and technology ,021001 nanoscience & nanotechnology ,Analytical Chemistry ,Adsorption ,020401 chemical engineering ,Chemical engineering ,Scientific method ,Magnetic nanoparticles ,Coagulation (water treatment) ,Seeding ,0204 chemical engineering ,Turbidity ,skin and connective tissue diseases ,0210 nano-technology - Abstract
Magnetic seeding coagulation-flocculation (MCF) process was evaluated by jar tests compared to a reference coagulation-flocculation (CF) process. Steps were made toward elucidating the underlying roles of magnetic particles (MPs) in MCF process. The results indicated that MPs addition could significantly accelerate flocs sedimentation and enhance pollutants removal. With an optimal strategy of adding the composite PACl/MPs (MPACl, 15/30 mg/L) first followed by 0.4 mg/L PAM, turbidity, UV254 and TP were removed up to 96.7%, 80.8% and 95.7% in 5 min under applied magnetic field (0.5 T). In addition, the multifunction of MPs reduced the negative impacts of pH changes, resulting in a wider working pH range. Humic acid-like components adsorbed on MPs and MPs-Al species improved the UV254 removal in MCF process than that in CF process. For low turbidity water, MPs increased suspended particles concentration and served as nuclei to enhance the formation of settleable flocs, consistent with an increase in turbidity removal from 89.75% to 96.80%. The multiple roles of MPs (suspended particles, adsorbents and coagulants) in MCF process were thoroughly discussed. This study provides theoretical guidance for its application in real surface water treatment.
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- 2019
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31. Thenar Muscle Oxygen Saturation Levels: A Surrogate for Central Venous Oxygen Saturation?
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Dipankar Gupta, Himesh V. Vyas, Ravi S. Samraj, Maria Mejia, Maria Kerrigan, James C. Fudge, and Laura Wilson
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Male ,Adolescent ,Critical Care ,Critical Illness ,medicine.medical_treatment ,chemistry.chemical_element ,030204 cardiovascular system & hematology ,Intensive Care Units, Pediatric ,Oxygen ,Veins ,Young Adult ,03 medical and health sciences ,0302 clinical medicine ,Superior vena cava ,medicine ,Humans ,Prospective Studies ,Child ,Muscle, Skeletal ,Cardiac catheterization ,Pediatric intensive care unit ,Central line ,Spectroscopy, Near-Infrared ,business.industry ,Infant ,030208 emergency & critical care medicine ,Peripheral ,Thumb ,chemistry ,Child, Preschool ,Anesthesia ,Shock (circulatory) ,Pediatrics, Perinatology and Child Health ,Female ,medicine.symptom ,business ,Blood Gas Monitoring, Transcutaneous ,Biomarkers ,Thenar eminence - Abstract
Purpose. Shock is associated with increased tissue oxygen extraction. Near-infrared spectroscopy–derived thenar muscle tissue oxygenation (StO2) levels can provide an estimate of the oxygen supply-demand balance at the tissue level. We hypothesized that thenar StO2 levels would correlate with central venous oxygen saturation (ScvO2) levels, the gold standard for global tissue oxygen extraction in the body. Methods. We prospectively enrolled 60 pediatric subjects admitted to pediatric intensive care unit or who underwent cardiac catheterization from September 2015 to March 2018. Thenar StO2 levels were measured using the InSpectra StO2 probe. Concurrent measurements of ScvO2 and peripheral tissue oxygenation (StO2) were achieved through simultaneous testing. For ScvO2, a central line placed in the superior vena cava was utilized for serum specimen collection, while the InSpectra probe recorded StO2 measurements from the thenar eminence of the patient’s right hand. Results. Sixty observations of thenar StO2 and ScvO2 levels were derived from 60 subjects. Mean thenar StO2 levels were 74.72 ± 11.18% and displayed significant correlation with paired ScvO2 measurements ( m = 72.17 ± 9.77%; ρ = 0.317, P = .018). Correlation was much more significant in subjects who were not on mechanical ventilatory support as opposed to those who were on it ( ρSORA = 0.496, PSORA = .003, vs ρVENT = 0.161, PVENT = .433). A thenar StO2 of 73% had a sensitivity of 80% and a specificity of 77.8% in predicting an ScvO2 of less than 65%. Conclusion. This is the first study to report correlation of thenar StO2 and ScvO2 levels in children. Our study results show a significant correlation between these levels. Thenar StO2 measurements may have a role in the bedside management of critically ill children in whom ScvO2 monitoring is not available.
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- 2019
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32. Designing Multivalent Ligands to Control Biological Interactions: From Vaccines and Cellular Effectors to Targeted Drug Delivery
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Mark Stathos, Ravi S. Kane, Ana Castro, Ammar Arsiwala, and Steven J. Frey
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Vaccines ,Cell signaling ,010405 organic chemistry ,Ligand ,Chemistry ,Effector ,Organic Chemistry ,General Chemistry ,Computational biology ,Ligands ,010402 general chemistry ,01 natural sciences ,Biochemistry ,0104 chemical sciences ,Drug Delivery Systems ,Targeted drug delivery ,Cell Line, Tumor ,Drug Design ,Animals ,Humans ,Immunologic Factors ,Signal Transduction - Abstract
Multivalent interactions in which multiple ligands on one object bind to multiple receptors on another are commonly found in natural biological systems. In addition, these interactions can lead to increased strength and selectivity when compared to the corresponding monovalent interaction. These attributes have also guided the design of synthetic multivalent ligands to control biological interactions. This review will highlight the recent literature describing the use of multivalent ligand display in the design of vaccines, immunomodulators, cell signaling effectors, and vehicles for targeted drug delivery.
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- 2019
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33. Assessment of acute toxicity and biochemical responses to chlorpyrifos, cypermethrin and their combination exposed earthworm, Eudrilus eugeniae
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R.K. Tiwari, Shikha Singh, and Ravi S. Pandey
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Pyrethroid ,biology ,Health, Toxicology and Mutagenesis ,Earthworm ,010501 environmental sciences ,Pesticide ,Toxicology ,biology.organism_classification ,01 natural sciences ,Acute toxicity ,Cypermethrin ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Eudrilus eugeniae ,chemistry ,lcsh:RA1190-1270 ,Chlorpyrifos ,Toxicity ,030217 neurology & neurosurgery ,0105 earth and related environmental sciences ,lcsh:Toxicology. Poisons - Abstract
Recurrent application of chemical pesticides in the agricultural fields have adverse impact on flora and fauna of soil ecosystem. Earthworms immensely contribute in increasing the fertility of soil. They may act as a bioindicator for the ecotoxicological analysis of pesticide induced soil pollution. Earthworms, Eudrilus eugeniae were exposed to different concentrations of pesticides chlorpyrifos (OP), cypermethrin (a pyrethroid) and their combination for 48 h by paper contact toxicity method. The LC50 for commercial grade of chlorpyrifos, cypermethrin and combined pesticides were determined as 0.165, 0.066 and 0.020 μg/cm2, respectively. To assess the sub-lethal effect of these pesticides, E. eugeniae were exposed to 5% and 10% of LC50 of the pesticides for 48 h. Variation in morpho-behavioural changes such as coiling, clitellar swelling, mucus release, bleeding and body fragmentation in earthworms were observed after exposure of both pesticides and their combination. Various biochemical estimations such as specific activity of acetylcholinesterase (AChE), superoxide dismutase (SOD), catalase (CAT), glutathione -S-transferase (GST); levels of lipid peroxidation (LPO) and reduced glutathione (GSH) were carried out in different body segments. Significant changes in these stress markers were observed at low and high sub-acute concentration of pesticides exposed earthworm, Eudrilus eugeniae. Such changes indicate potential health risk to E. eugeniae if exposed to the high concentrations of these pesticides accumulated in soil. Keywords: AChE activity, Stress markers, Chlorpyrifos, Cypermethrin, Chlorpyrifos + Cypermethrin, Eudrilus eugeniae
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- 2019
34. Natural Compound Oridonin Inhibits Endotoxin-Induced Inflammatory Response of Activated Hepatic Stellate Cells
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Jia Zhou, Hong-Yan Tie, Christian Sommerhalder, Frederick J. Bohanon, Claire B. Cummins, Victoria G. Rontoyanni, Ravi S. Radhakrishnan, Omar Nunez Lopez, and Xiaofu Wang
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Lipopolysaccharides ,0301 basic medicine ,Article Subject ,Anti-Inflammatory Agents ,IκB kinase ,Pharmacology ,General Biochemistry, Genetics and Molecular Biology ,Cell Line ,Proinflammatory cytokine ,03 medical and health sciences ,0302 clinical medicine ,Hepatic Stellate Cells ,Humans ,General Immunology and Microbiology ,Cell adhesion molecule ,Chemistry ,General Medicine ,3. Good health ,IκBα ,030104 developmental biology ,Cell culture ,030220 oncology & carcinogenesis ,Hepatic stellate cell ,Cytokines ,Phosphorylation ,Signal transduction ,Diterpenes, Kaurane ,Cell Adhesion Molecules ,Research Article ,Signal Transduction - Abstract
Hepatic stellate cells (HSCs) play an important role in hepatic fibrogenesis and inflammatory modulation. Endotoxin is dramatically increased in portal venous blood after serious injury and can contribute to liver damage. However, the mechanism underlying endotoxin’s effects on HSCs remains largely unknown. Oridonin is a bioactive diterpenoid isolated from Rabdosia rubescens that exhibits anti-inflammatory properties in different tissues. In the present study, we determined the effects of oridonin on endotoxin-induced inflammatory response and signaling pathways in vitro. The production of proinflammatory cytokines in activated human HSCs line LX-2 was measured by ELISA and Western blots. Immunofluorescence and nuclear fractionation assay were used to determine NF-κB activity. Oridonin treatment significantly inhibited LPS-induced proinflammatory cytokines IL-1β, IL-6, and MCP-1 production as well as cell adhesion molecules ICAM-1 and VCAM-1. Additionally, oridonin blocked LPS-induced NF-κB p65 nuclear translocation and DNA binding activity. Oridonin prevented LPS-stimulated NF-κB regulator IKKα/β and IκBα phosphorylation and IκBα degradation. Combined treatment of oridonin and an Hsp70 substrate binding inhibitor synergistically suppressed LPS-stimulated proinflammatory cytokines and NF-κB pathway activation. Therefore, oridonin inhibits LPS-stimulated proinflammatory mediators through IKK/IκBα/NF-κB pathway. Oridonin could be a promising agent for a hepatic anti-inflammatory.
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- 2018
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35. Specific Inhibition of Heparanase by a Glycopolymer with Well-Defined Sulfation Pattern Prevents Breast Cancer Metastasis in Mice
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Ravi S. Loka, Uri Barash, Hien M. Nguyen, Israel Vlodavsky, and Eric T. Sletten
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Materials science ,Glycopolymer ,Cell ,010402 general chemistry ,01 natural sciences ,Article ,Metastasis ,Mice ,03 medical and health sciences ,chemistry.chemical_compound ,Sulfation ,In vivo ,Cell Line, Tumor ,Human Umbilical Vein Endothelial Cells ,medicine ,Animals ,Humans ,General Materials Science ,Heparanase ,Enzyme Inhibitors ,Neoplasm Metastasis ,IC50 ,Glucuronidase ,030304 developmental biology ,0303 health sciences ,Neovascularization, Pathologic ,Heparin ,Mammary Neoplasms, Experimental ,Heparan sulfate ,medicine.disease ,Neoplasm Proteins ,0104 chemical sciences ,P-Selectin ,medicine.anatomical_structure ,chemistry ,Cancer research ,Female - Abstract
Heparanase, the heparan sulfate polysaccharide degrading endoglycosidase enzyme, has been correlated with tumor angiogenesis and metastasis and therefore has become a potential target for anticancer drug development. In this systematic study, the sulfation pattern of the pendant disaccharide moiety on synthetic glycopolymers was synthetically manipulated to achieve optimal heparanase inhibition. Upon evaluation, a glycopolymer with 12 repeating units was determined to be the most potent inhibitor of heparanase (IC50 = 0.10 ± 0.36 nM). This glycopolymer was further examined for cross-bioactivity using a solution-based competitive biolayer interferometry assay with other HS-binding proteins (growth factors, P-selectin, and platelet factor 4), which are responsible for mediating angiogenic activity, cell metastasis, and antibody-induced thrombocytopenia. The synthetic glycopolymer has low affinity for these HS-binding proteins in comparison to natural heparin. In addition, the glycopolymer possessed no proliferative properties toward human umbilical endothelial cells (HUVECs) and a potent antimetastatic effect against 4T1 mammary carcinoma cells. Thus, our study not only establishes a specific inhibitor of heparanase with high affinity but also illustrates the high effectiveness of this multivalent heparanase inhibitor in inhibiting experimental metastasis in vivo.
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- 2018
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36. Refocusing the Immune Response to Selected Epitopes on a Zika Virus Protein Antigen by Nanopatterning
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Juan Manuel Carreño, James Duehr, Florian Krammer, Ana Castro, and Ravi S. Kane
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Biomedical Engineering ,Pharmaceutical Science ,02 engineering and technology ,010402 general chemistry ,Antibodies, Viral ,01 natural sciences ,Epitope ,Article ,Zika virus ,Biomaterials ,Epitopes ,Immune system ,Antigen ,Viral Envelope Proteins ,Humans ,chemistry.chemical_classification ,biology ,Chemistry ,Zika Virus Infection ,Immunity ,Zika Virus ,021001 nanoscience & nanotechnology ,biology.organism_classification ,Virology ,Antibodies, Neutralizing ,In vitro ,0104 chemical sciences ,Amino acid ,Immunization ,biology.protein ,Antibody ,0210 nano-technology - Abstract
Infections with Zika virus (ZIKV) have been linked to the development of severe central nervous system disorders, but the need for a ZIKV vaccine remains unmet. Although the design of vaccines that elicit antibodies targeting domain III (DIII) of the ZIKV envelope (E) protein as an antigen is an attractive strategy, poorly neutralizing or cross-reactive antibodies that target the E protein may lead to antibody-dependent enhancement of disease. We therefore decided to use our previously reported nanopatterning technique, which combines the site-specific incorporation of non-canonical amino acids with site-specific functionalization of the protein with polyethylene glycol (PEG), to shield selected epitopes on DIII. We designed and characterized two different nanopatterned DIII variants and demonstrated that epitope shielding with PEG completely inhibits the binding of epitope-specific antibodies in vitro. Furthermore, immunization with multivalent nanopatterned DIII antigens resulted in the refocusing of the antibody response towards the exposed epitopes on the protein surface and away from potentially enhancing epitopes. This ability to redirect the antibody response towards targeted regions of the DIII protein should be useful for the design of effective and safe ZIKV vaccines.
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- 2021
37. Astrocytic reactivity triggered by defective autophagy and metabolic failure causes neurotoxicity in frontotemporal dementia type 3
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Henriette Haukedal, Jørgen E. Nielsen, Sarayu Ramakrishna, Abinaya Chandrasekaran, Yu Zhang, Troels Tolstrup Nielsen, Giulia I. Corsi, Nadezhda Tsankova Doncheva, Maria Pihl, Andras Dinnyes, Sissel Ida Schmidt, Poul Hyttel, Julianna Kobolák, Blanca I. Aldana, Susanna Cirera, Morten Meyer, Dasaradhi Palakodeti, Sheetal Ambardar, Kristine K. Freude, Ravi S. Muddashetty, Miriam Kolko, Benjamin Schmid, Jan Gorodkin, Katarina Stoklund Dittlau, and Claudia Salcedo
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autophagy ,Induced Pluripotent Stem Cells ,hiPSC-derived astrocytes ,Biology ,Mitochondrion ,Biochemistry ,Article ,Mice ,reactive astrocytes ,Genetics ,medicine ,Animals ,Homeostasis ,Humans ,Genetic Predisposition to Disease ,RNA-Seq ,NF-kB ,Cells, Cultured ,chemistry.chemical_classification ,Reactive oxygen species ,Endosomal Sorting Complexes Required for Transport ,Gene Expression Profiling ,Neurodegeneration ,Autophagy ,Neurotoxicity ,CHMP2B ,Cell Differentiation ,Cell Biology ,Charged multivesicular body protein 2B ,medicine.disease ,cytokines ,Cell biology ,Mitochondria ,medicine.anatomical_structure ,chemistry ,mitochondrial fusion ,Astrocytes ,Frontotemporal Dementia ,FTD3 ,Mutation ,Glycolysis ,complement 3 ,Developmental Biology ,Astrocyte ,Signal Transduction - Abstract
Summary Frontotemporal dementia type 3 (FTD3), caused by a point mutation in the charged multivesicular body protein 2B (CHMP2B), affects mitochondrial ultrastructure and the endolysosomal pathway in neurons. To dissect the astrocyte-specific impact of mutant CHMP2B expression, we generated astrocytes from human induced pluripotent stem cells (hiPSCs) and confirmed our findings in CHMP2B mutant mice. Our data provide mechanistic insights into how defective autophagy causes perturbed mitochondrial dynamics with impaired glycolysis, increased reactive oxygen species, and elongated mitochondrial morphology, indicating increased mitochondrial fusion in FTD3 astrocytes. This shift in astrocyte homeostasis triggers a reactive astrocyte phenotype and increased release of toxic cytokines, which accumulate in nuclear factor kappa b (NF-κB) pathway activation with increased production of CHF, LCN2, and C3 causing neurodegeneration., Graphical abstract, Highlights • FTD3 iPSC-derived astrocytes display impaired autophagy • Impaired autophagy affects mitochondria turnover, glucose hypometabolism and TCA cycle • FTD3 astrocytes contribute to reactive gliosis by increased C3, LCN2, IL6, and IL8 • Reactive astrocyte phenotypes are present in both in vitro and in vivo models, Chandrasekaran et al. show the mechanistic insights into how defective autophagy causes perturbed mitochondrial dynamics with impaired glycolysis, increased reactive oxygen species, and elongated mitochondrial morphology in frontotemporal dementia type 3 astrocytes contributing to neurodegeneration.
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- 2021
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38. Astrocytic Reactivity Triggered by defective Mitophagy Activates NF-kB Signaling and Causes Neurotoxicity in Frontotemporal Dementia Type 3
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Troels Tolstrup Nielsen, Julianna Kobolák, Abinaya Chandrasekaran, Dasaradhi Palakodeti, Jan Gorodkin, Henriette Haukedal, Claudia Salcedo, Ravi S. Muddashetty, Nadezhda Tsankova Doncheva, Poul Hyttel, Sarayu Ramakrishna, Yu Zhang, Sissel Ida Schmidt, Miriam Kolko, Katarina Stoklund Dittlau, Kristine K. Freude, Giulia I. Corsi, Blanca I. Aldana, Jørgen E. Nielsen, Scheetal Ambardar, Benjamin Schmid, Andras Dinnyes, Susanna Cirera, and Morten Meyer
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Chemistry ,Mitophagy ,Neurotoxicity ,medicine ,Reactivity (chemistry) ,medicine.disease ,Neuroscience ,Frontotemporal dementia - Abstract
Background: Frontotemporal dementia type 3 (FTD3) caused by a point mutation in the charged multivesicular body protein 2B (CHMP2B), affects mitochondrial ultrastructure and function as well as endosomal-lysosomal fusion in neurons. However, there is a critical knowledge gap in understanding how mutations in CHMP2B affect astrocytes. Hence, we investigated the disease mechanisms in astrocytes derived from hiPSC with mutations in CHMP2B and their impact on neurons.Methods: To dissect the astrocyte-specific impact of mutant CHMP2B expression, we generated astrocytes from human induced pluripotent stem cells (hiPSCs) from FTD3 patients and their CRISPR/Cas 9 gene edited isogenic controls and produced heterozygous and homozygous CHMP2B-mutant hiPSC via CRISPR/Cas 9 knock-in gene editing. Additionally, we confirmed our findings in CHMP2B mutant mice. The hiPSC were subjected to astrocyte differentiation and the mutation dependent effects were investigated using immunocytochemistry, western blot, cytokine assays, transmission electron microscopy, RNA-sequencing and gas chromatography-mass spectrometry. Finally, neurons were exposed to conditioned media of mutant astrocytes and viability, growth and motility were measured.Results: To dissect the astrocyte-specific impact of mutant CHMP2B expression, we generated astrocytes from human induced pluripotent stem cells (hiPSCs) and confirmed our findings in CHMP2B mutant mice. Our findings include perturbed mitochondrial dynamics with impaired glycolysis, increased reactive oxygen species and elongated mitochondrial morphology, indicating increased mitochondrial fusion in FTD3 astrocytes. Furthermore, we identified a shift in astrocyte homeostasis triggering a reactive astrocyte phenotype and increased release of toxic cytokines. This cumulates in NF-kB pathway activation with increased production of CHF, LCN2 and C3, which cause neurodegeneration. The neurotoxic effect was investigated by exposing hiPSC-derived neurons to astrocyte-conditioned media, which severely reduced neurite outgrowth capacities. Rescue experiments targeting ROS could restore ROS levels back to normal levels, indicating that the impaired removal of abnormal mitochondria triggers the pathological cascade in CHMP2B mutant astrocytes culminating in the formation of neurotoxic reactive astrocytes.Conclusion :Our data provide mechanistic insights into how defective mitophagy causes impaired mitochondrial fission, leading to the adoption of reactive astrocyte properties with increased cytokine release, NFkB activation and elevated expression of neurotoxic proteins in FTD3.
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- 2021
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39. Evaluation of effects the ocular metrics (eye movements and ocular aberrations) have on image quality of in vivo retinal optical coherence tomography angiography (OCTA)
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Ravi S. Jonnal, Denise Valente, Robert J. Zawadzki, John S. Werner, and Kari V. Vienola
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genetic structures ,medicine.diagnostic_test ,Image quality ,Computer science ,Phase (waves) ,Eye movement ,Retinal ,eye diseases ,chemistry.chemical_compound ,Oct angiography ,Optical coherence tomography ,chemistry ,Phase correlation ,medicine ,Eye tracking ,sense organs ,Biomedical engineering - Abstract
Accurate and reproducible OCT angiography (OCTA) measurements are highly dependent on the overall phase stability of the sample. Raster-scanning OCT systems are vulnerable to eye motion, which makes phase correlation impossible if the retinal displacement is too large. Numerical methods exist to correct components of phase shifts due to the axial movement, but that due to lateral movement bigger, then imaging spot are not generally correctable. Real-time eye tracking provides a method to reduce the phase shifts caused by lateral eye movement. Here we report the advancements on monitoring ocular metrics during OCTA acquisition and its effects on image quality.
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- 2021
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40. Cardiovascular Manifestations in Inflammatory Bowel Disease: A Systematic Review of the Pathogenesis and Management of Pericarditis
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Domonick K Gordon, Ravi S Patel, Ayat Hashim, Farrukh Ahmad, Adiona Llukmani, Dutt S Patel, Sai Rohit Reddy, and Dana R Haddad
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medicine.medical_specialty ,Cardiology ,Disease ,030204 cardiovascular system & hematology ,Inflammatory bowel disease ,pericarditis ,03 medical and health sciences ,Pericarditis ,chemistry.chemical_compound ,0302 clinical medicine ,Pharmacotherapy ,Sulfasalazine ,inflammatory bowel disease ,Internal medicine ,Internal Medicine ,Medicine ,ulcerative colitis ,Crohn's disease ,business.industry ,General Engineering ,Gastroenterology ,Balsalazide ,extraintestinal manifestations ,medicine.disease ,Ulcerative colitis ,digestive system diseases ,crohn’s disease ,chemistry ,business ,030217 neurology & neurosurgery ,medicine.drug - Abstract
Inflammatory bowel disease (IBD) is a chronic condition of the bowel that can be further categorized into ulcerative colitis and Crohn's disease. Rarely, this condition can be associated with pericarditis, which can be an extraintestinal manifestation of the disease or drug-induced. This review aims to determine the pathogenesis and management of pericarditis in IBD. In this review, the goal is to elucidate the pathogenesis of pericarditis in IBD and determine if pericarditis is an extraintestinal manifestation of IBD or a complication of current drug therapy used to manage IBD. Additionally, this review intends to explain the first-line management of pericarditis in IBD and explore the role of biologicals in attenuating pericarditis. An electronic search was conducted to identify relevant reports of pericarditis in IBD, and a quality assessment was conducted to identify high-quality articles according to the inclusion criteria. Full-text articles from inception to November 2020 were included, while non-English articles, gray literature, and animal studies were excluded. The majority of studies suggest that pericarditis arises as a complication of drug therapy by 5-aminosalicylic acid derivatives such as sulfasalazine, mesalamine, and balsalazide, and it occurs due to IgE-mediated allergic reactions, direct cardiac toxicity, cell-mediated hypersensitivity reactions, and humoral antibody response to therapy. Drug cessation or the initiation of a corticosteroid regimen seems to be the most effective means of managing pericarditis in IBD due to drug therapy or an extraintestinal manifestation.
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- 2021
41. The Importance of Sphingosine Kinase in Breast Cancer: A Potential for Breast Cancer Management
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Domonick K Gordon, Ravi S Patel, Sai Rohit Reddy, Dutt S Patel, Adiona Llukmani, Majdi Abu Sneineh, Farrukh Ahmad, and Ayat Hashim
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medicine.medical_treatment ,Sphingosine kinase ,030204 cardiovascular system & hematology ,Metastasis ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Breast cancer ,Pathology ,breast neoplasms ,medicine ,Sphingosine-1-phosphate ,Tumor microenvironment ,Sphingosine ,business.industry ,General Engineering ,medicine.disease ,Radiation therapy ,Oncology ,chemistry ,Docetaxel ,sphingosine kinase ,sphingosine-1-phosphate ,Cancer research ,lipids (amino acids, peptides, and proteins) ,business ,030217 neurology & neurosurgery ,medicine.drug - Abstract
Breast cancer management includes a combination of surgery, radiation therapy, and chemotherapy. While this management has proven effective, it is not perfect. To expand the umbrella of management to resistant breast cancer tumors, researchers have explored the idea of sphingosine kinase (SphK) and sphingosine-1-phosphate (S1P) as a potential target for treatment. In this article, we review the mechanism of the sphingosine kinase/sphingosine-1-phosphate (SphK/S1P) axis along with its effect on the tumor microenvironment (TME) and compounds that have been studied inhibiting the SphK/S1P axis. We searched for relevant articles in the last five years in Medline and PubMed Central. Inclusion criteria, exclusion criteria, and quality checklists were applied to identify the most relevant articles. We compiled the information that has been summarized in the respective tables and figures provided in this review. The metabolism of sphingolipids was summarized, followed by the SphK/S1P upregulation in breast cancer cells. The variety of effects by upregulation of SphK led to an increase in inflammation, growth, and metastasis in breast cancer tumors. The increase in S1P also impacted the TME, including the cells and surrounding tissue, allowing the breast tumors to thrive. The final point made was a summary of the compounds and drugs that inhibited the SphK/S1P axis. They have proven their effectiveness and show even greater efficacy in combination with docetaxel and doxorubicin in preclinical studies. In conclusion, what is known about the SphK/S1P axis within breast cancer cells is immense but incomplete as we summarize what is known so far. Having a complete picture will allow a faster transition to application in the clinical field but clinical trials have not commenced as of yet.
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- 2021
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42. Liquiritin from Glycirrhyza Glabra L (Fabaceae) - a Natural Derived Drug, as a Potential Inhibitor for SARS-CoV-2
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Padamnabhi S. Nagar, Ravi S. Patel, Kapil Yadav, Amisha Patel, Akash Vanzara, and Nimisha Patel
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Drug ,biology ,Traditional medicine ,media_common.quotation_subject ,Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) ,Potential candidate ,Hydroxychloroquine ,Fabaceae ,AutoDock ,biology.organism_classification ,chemistry.chemical_compound ,chemistry ,medicine ,Glycyrrhiza ,Liquiritin ,medicine.drug ,media_common - Abstract
Novel Corona virus-2 (Covid-19) is spreading and causing major damage around the globe and constantly increasing daily. There is a prerequisite of expeditious development of safe and efficient drugs for such a contagious disease. In this regard, utilization of a computational approach with an aim to provide potential enzyme inhibitors derived from natural resources will give a providential therapy. The present study investigated one of the promising plants namely Glycyrrhiza glabra L. It has various medicinal properties viz. anti-inflammatory, anti-cancer, anti-demulcent, expectorant, etc. In-Silico Analysis of liquiritin against SARS-CoV-2 Mpro was carried out using Autodock 4.2.6 and results were compared with presently prescribed drugs i.e. dexamethasone, remdesivir, hydroxychloroquine, and azithromycin. The binding energy of liquiritin was found to be -6.62 kcal/mol. It shows presence of hydrogen bond, hydrophobic interaction and electrostatic interaction with six active residues THR26, GLY143, CYS145, HIS 164, GLU166, and GLN189. Comparative studies investigated that dexamethasone, remdesivir, hydroxychloroquine, and azithromycin have four (THR26, GLY143, CYS145, GLU166), three (CYS145, GLU166, GLN189), four (GLY143, CYS145, HIS 164, GLN189) and two (GLU166, GLN189) identical active residues, respectively. The present study recommended liquiritin as a potential candidate against SARS-CoV-2 as it is naturally derived and has tremendous traditional usage against various diseases. However, in-vitro and in-vivo studies are required to prove its efficacy.
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- 2021
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43. Understanding the Bioaccumulation and Biosorption of Arsenic [As(III)] in Plants and Biotechnological Approaches for Its Bioremediation
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Ashok Kumar Jha, Ujjwal Kumar, and Ravi S. Singh
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Bioremediation ,Aqueous medium ,Chemistry ,Environmental remediation ,Bioaccumulation ,Environmental chemistry ,Biosorption ,chemistry.chemical_element ,Chelation ,Sorption isotherm ,Arsenic - Abstract
The efforts are being made globally regarding the development of low-cost, eco-friendly, and novel methods of remediation of arsenic from aqueous medium and soil. Biotechnological approaches of bioaccumulation and biosorption have emerged as an important tool in the ongoing research including the latest application of novel CRISPR/Cas9 technology that can enhance the rate of bioaccumulation. Expression modulation of genes and proteins including transcription factor, transporter, and mi-RNAs during As(III) accumulation plays an important role in bioaccumulation besides other factors such as statistical factor, percentage removal, and adsorption isotherm. Biosorption mechanisms that include coordination, chelation, ion exchange, reduction, complexation, and movement through different parts of plants are also important. In this chapter, keeping in view the importance of bioaccumulation and biosorption by plants, we have discussed the mechanism of bioaccumulation and biosorption of As(III) in plants, different kinetic models including pseudo-first order and pseudo-second order model and thermodynamic parameters like entropy change, enthalpy change, and Gibbs free energy change determine the spontaneity and criteria of reaction and biotechnological approaches for As(III) bioremediation.
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- 2021
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44. Integrated Silicon Photonics Transceiver Module for 100Gbit/s 20km Transmission
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Ravi S. Tummidi, Marco Mazzini, Neiman Jarrett S, Kumar Lakshmikumar, Mary Nadeau, Mark Webster, Cristiana Muzio, Sanjay Sunder, Weizhuo Li, Traverso Matthew J, Alberto Cervasio, Craig S. Appel, and Alex Kurylak
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Silicon photonics ,Optical fiber ,Silicon ,business.industry ,Computer science ,ComputerSystemsOrganization_COMPUTER-COMMUNICATIONNETWORKS ,Electrical engineering ,chemistry.chemical_element ,Transceiver chip ,100 Gigabit Ethernet ,law.invention ,chemistry ,Transmission (telecommunications) ,Hardware_GENERAL ,law ,Optical receivers ,Hardware_INTEGRATEDCIRCUITS ,ComputerSystemsOrganization_SPECIAL-PURPOSEANDAPPLICATION-BASEDSYSTEMS ,Transceiver ,business - Abstract
The architecture, packaging, and performance of a Silicon Photonics single transceiver chip PAM4 optical QSFP28 transceiver module for 100 Gigabit Ethernet compliant to 100GBASE- LR1 for 10km and extendable to over 20km SMF transmission is described.
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- 2021
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45. APOE4 affects basal and NMDAR mediated protein synthesis in neurons by perturbing calcium homeostasis
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Vishwaja Jhaveri, Sumita Chakraborty, Bjørn Holst, Ravi S Muddashetty, Gunnar K. Gouras, Bharti Nawalpuri, Kristine K. Freude, Sarayu Ramakrishna, Benjamin Schmid, and Sabine C. Konings
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Male ,Apolipoprotein E ,Adolescent ,Apolipoprotein E4 ,Induced Pluripotent Stem Cells ,chemistry.chemical_element ,Mice, Transgenic ,Calcium ,EEF2 ,Receptors, N-Methyl-D-Aspartate ,Rats, Sprague-Dawley ,Mice ,mental disorders ,Animals ,Homeostasis ,Humans ,Calcium Signaling ,Research Articles ,Cells, Cultured ,Cerebral Cortex ,Mice, Knockout ,Neurons ,Calcium metabolism ,Voltage-dependent calcium channel ,General Neuroscience ,Translation (biology) ,Rats ,Cell biology ,Mice, Inbred C57BL ,chemistry ,Protein Biosynthesis ,NMDA receptor ,lipids (amino acids, peptides, and proteins) ,Synaptic signaling ,human activities - Abstract
Apolipoprotein E (APOE), one of the primary lipoproteins in the brain has three isoforms in humans, APOE2, APOE3, and APOE4. APOE4 is the most well-established risk factor increasing the predisposition for Alzheimer's disease (AD). The presence of the APOE4 allele alone is shown to cause synaptic defects in neurons and recent studies have identified multiple pathways directly influenced by APOE4. However, the mechanisms underlying APOE4-induced synaptic dysfunction remain elusive. Here, we report that the acute exposure of primary cortical neurons or synaptoneurosomes to APOE4 leads to a significant decrease in global protein synthesis. Primary cortical neurons were derived from male and female embryos of Sprague Dawley (SD) rats or C57BL/6J mice. Synaptoneurosomes were prepared from P30 male SD rats. APOE4 treatment also abrogates the NMDA-mediated translation response indicating an alteration of synaptic signaling. Importantly, we demonstrate that both APOE3 and APOE4 generate a distinct translation response which is closely linked to their respective calcium signature. Acute exposure of neurons to APOE3 causes a short burst of calcium through NMDA receptors (NMDARs) leading to an initial decrease in protein synthesis which quickly recovers. Contrarily, APOE4 leads to a sustained increase in calcium levels by activating both NMDARs and L-type voltage-gated calcium channels (L-VGCCs), thereby causing sustained translation inhibition through eukaryotic translation elongation factor 2 (eEF2) phosphorylation, which in turn disrupts the NMDAR response. Thus, we show that APOE4 affects basal and activity-mediated protein synthesis responses in neurons by affecting calcium homeostasis.SIGNIFICANCE STATEMENTDefective protein synthesis has been shown as an early defect in familial Alzheimer's disease (AD). However, this has not been studied in the context of sporadic AD, which constitutes the majority of cases. In our study, we show that Apolipoprotein E4 (APOE4), the predominant risk factor for AD, inhibits global protein synthesis in neurons. APOE4 also affects NMDA activity-mediated protein synthesis response, thus inhibiting synaptic translation. We also show that the defective protein synthesis mediated by APOE4 is closely linked to the perturbation of calcium homeostasis caused by APOE4 in neurons. Thus, we propose the dysregulation of protein synthesis as one of the possible molecular mechanisms to explain APOE4-mediated synaptic and cognitive defects. Hence, the study not only suggests an explanation for the APOE4-mediated predisposition to AD, it also bridges the gap in understanding APOE4-mediated pathology.
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- 2021
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46. APOE4 affects basal and NMDAR mediated protein synthesis in neurons by perturbing calcium homeostasis
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Vishwaja Jhaveri, Bjørn Holst, Kristine K. Freude, Ravi S. Muddashetty, Gunnar K. Gouras, Sabine C. Konings, Benjamin Schmid, Sarayu Ramakrishna, and Sumita Chakraborty
- Subjects
Calcium metabolism ,Apolipoprotein E ,chemistry ,mental disorders ,chemistry.chemical_element ,Phosphorylation ,NMDA receptor ,lipids (amino acids, peptides, and proteins) ,Translation (biology) ,Synaptic signaling ,Calcium ,EEF2 ,Cell biology - Abstract
Apolipoprotein E (APOE), one of the primary lipoproteins in the brain has three isoforms in humans – APOE2, APOE3, and APOE4. APOE4 is the most well-established risk factor increasing the pre-disposition for Alzheimer’s disease. The presence of the APOE4 allele alone is shown to cause synaptic defects in neurons and recent studies have identified multiple pathways directly influenced by APOE4. However, the mechanisms underlying APOE4 induced synaptic dysfunction remain elusive. Here, we report that the acute exposure of primary cortical neurons to APOE4 leads to a significant decrease in global protein synthesis. APOE4 treatment also abrogates the NMDA mediated translation response indicating an impairment of synaptic signaling. Importantly, we demonstrate that both APOE3 and APOE4 generate a distinct translation response which is closely linked to their respective calcium signature. Acute exposure to APOE3 causes a short burst of calcium through NMDARs in neurons leading to an initial decrease in protein synthesis which quickly recovers. Contrarily, APOE4 leads to a sustained increase in calcium levels by activating both NMDARs and L-VGCCs, thereby causing sustained translation inhibition through eEF2 phosphorylation, which in turn disrupts NMDAR response. Thus, we show that APOE4 affects basal and activity mediated protein synthesis response in neurons by affecting calcium homeostasis. We propose this as a possible mechanism to explain the synaptic dysfunction caused by APOE4.Highlights / SummaryAPOE3 treatment causes a short burst of calcium through NMDARs, leading to an acute increase in eEF2 phosphorylation which eventually recovers to basal levels.Global translation follows a similar temporal profile of initial inhibition followed by recovery in APOE3 treated neurons, thus unaffecting the NMDA mediated translation response.APOE4 treatment activates both NMDARs and L-VGCCs leading to a marked elevation in calcium levels, thus causing sustained increase in eEF2 phosphorylation as well as global translation inhibition.Hence, the NMDA mediated response is perturbed, potentially causing a stress-related phenotype in APOE4 treated neurons.Thus, different calcium signatures and sources lead to distinct temporal profiles of translation.
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- 2020
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47. Visible light OCT improves imaging through a highly scattering retinal pigment epithelial wall
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Aaron M. Kho, Glenn Yiu, Ravi S. Jonnal, Tingwei Zhang, Robert J. Zawadzki, and Vivek J. Srinivasan
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genetic structures ,Light ,Forward scatter ,02 engineering and technology ,Retinal Pigment Epithelium ,Optical Physics ,Signal-To-Noise Ratio ,Eye ,01 natural sciences ,Scattering ,chemistry.chemical_compound ,Mice ,Scattering, Radiation ,Absorption (electromagnetic radiation) ,Tomography ,Quantum Physics ,Melanosomes ,Radiation ,medicine.diagnostic_test ,021001 nanoscience & nanotechnology ,Atomic and Molecular Physics, and Optics ,medicine.anatomical_structure ,0210 nano-technology ,Monte Carlo Method ,Tomography, Optical Coherence ,Visible spectrum ,Materials science ,Bioengineering ,Article ,010309 optics ,Optics ,Optical coherence tomography ,0103 physical sciences ,medicine ,Animals ,Humans ,Electrical and Electronic Engineering ,Eye Disease and Disorders of Vision ,Melanosome ,Retinal pigment epithelium ,business.industry ,Neurosciences ,Retinal ,eye diseases ,chemistry ,Optical Coherence ,sense organs ,Bruch Membrane ,business - Abstract
Here we provide a counter-example to the conventional wisdom in biomedical optics that longer wavelengths aid deeper imaging in tissue. Specifically, we investigate visible light optical coherence tomography of Bruch’s membrane (BM) in the non-pathologic eyes of humans and two mouse strains. Surprisingly, we find that shorter visible wavelengths improve the visualization of BM in pigmented eyes, where it is located behind a highly scattering layer of melanosomes in the retinal pigment epithelium (RPE). Monte Carlo simulations of radiative transport suggest that, while absorption and scattering are higher at shorter wavelengths, detected multiply scattered light from the RPE is preferentially attenuated relative to detected backscattered light from the BM.
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- 2020
48. A Systematic Review of Air Quality Sensors, Guidelines, and Measurement Studies for Indoor Air Quality Management
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He Zhang and Ravi S. Srinivasan
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Ozone ,010504 meteorology & atmospheric sciences ,media_common.quotation_subject ,Geography, Planning and Development ,TJ807-830 ,010501 environmental sciences ,Management, Monitoring, Policy and Law ,TD194-195 ,01 natural sciences ,Occupational safety and health ,Renewable energy sources ,Transport engineering ,chemistry.chemical_compound ,Sick building syndrome ,Indoor air quality ,ASHRAE 90.1 ,Quality (business) ,GE1-350 ,guidelines ,Air quality index ,0105 earth and related environmental sciences ,media_common ,Pollutant ,Environmental effects of industries and plants ,Renewable Energy, Sustainability and the Environment ,low-cost sensor ,Environmental sciences ,chemistry ,pollutants ,standards ,Environmental science ,sick building syndrome ,indoor air quality - Abstract
The existence of indoor air pollutants—such as ozone, carbon monoxide, carbon dioxide, sulfur dioxide, nitrogen dioxide, particulate matter, and total volatile organic compounds—is evidently a critical issue for human health. Over the past decade, various international agencies have continually refined and updated the quantitative air quality guidelines and standards in order to meet the requirements for indoor air quality management. This paper first provides a systematic review of the existing air quality guidelines and standards implemented by different agencies, which include the Ambient Air Quality Standards (NAAQS); the World Health Organization (WHO); the Occupational Safety and Health Administration (OSHA); the American Conference of Governmental Industrial Hygienists (ACGIH); the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE); the National Institute for Occupational Safety and Health (NIOSH); and the California ambient air quality standards (CAAQS). It then adds to this by providing a state-of-art review of the existing low-cost air quality sensor (LCAQS) technologies, and analyzes the corresponding specifications, such as the typical detection range, measurement tolerance or repeatability, data resolution, response time, supply current, and market price. Finally, it briefly reviews a sequence (array) of field measurement studies, which focuses on the technical measurement characteristics and their data analysis approaches.
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- 2020
49. Kilohertz retinal FF-SS-OCT and flood imaging with hardware-based adaptive optics
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Denise Valente, Ravi S. Jonnal, Kari V. Vienola, and Robert J. Zawadzki
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genetic structures ,Computer science ,Image quality ,Bioengineering ,Optical Physics ,Eye ,01 natural sciences ,Fundus camera ,Article ,010309 optics ,chemistry.chemical_compound ,03 medical and health sciences ,Optical coherence tomography ,Interference (communication) ,Foveal ,Clinical Research ,0103 physical sciences ,medicine ,Adaptive optics ,Eye Disease and Disorders of Vision ,030304 developmental biology ,Retina ,0303 health sciences ,CMOS sensor ,medicine.diagnostic_test ,business.industry ,Stray light ,Resolution (electron density) ,Neurosciences ,Retinal ,Materials Engineering ,Atomic and Molecular Physics, and Optics ,eye diseases ,medicine.anatomical_structure ,chemistry ,Biomedical Imaging ,sense organs ,business ,Computer hardware ,Biotechnology ,Coherence (physics) - Abstract
A retinal imaging system was designed for full-field (FF) swept-source (SS) optical coherence tomography (OCT) with cellular resolution. The system incorporates a real-time adaptive optics (AO) subsystem and a very high-speed CMOS sensor, and is capable of acquiring volumetric images of the retina at rates up to 1 kHz. While digital aberration correction (DAC) is an attractive potential alternative to AO, it has not yet been shown to provide resolution allowing visualization of cones in the fovea, where early detection of functional deficits is most critical. Here we demonstrate that FF-SS-OCT with hardware AO permits resolution of foveal cones, imaged at eccentricities of 1° and 2°, with volume rates adequate to measure light-evoked changes in photoreceptors. With the reference arm blocked, the system can operate as a kilohertz AO flood illumination fundus camera with adjustable temporal coherence and is expected to allow measurement of light-evoked changes caused by common path interference in photoreceptor outer segments (OS). In this paper, we describe the system’s optical design, characterize its performance, and demonstrate its ability to produce images of the human photoreceptor mosaic.
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- 2020
50. Optoretinogram: optical measurement of human cone and rod photoreceptor responses to light
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John S. Werner, Denise Valente, Robert J. Zawadzki, Mehdi Azimipour, Ravi S. Jonnal, and Kari V. Vienola
- Subjects
genetic structures ,Light ,Bioengineering ,02 engineering and technology ,Optical Physics ,Neurodegenerative ,Eye ,01 natural sciences ,Article ,010309 optics ,Ophthalmoscopy ,chemistry.chemical_compound ,Optics ,Optical coherence tomography ,Retinal Rod Photoreceptor Cells ,Clinical Research ,0103 physical sciences ,Retinitis pigmentosa ,medicine ,Humans ,Electrical and Electronic Engineering ,Adaptive optics ,Eye Disease and Disorders of Vision ,Physics ,Quantum Physics ,medicine.diagnostic_test ,business.industry ,Neurosciences ,Retinal ,Macular degeneration ,021001 nanoscience & nanotechnology ,medicine.disease ,eye diseases ,Atomic and Molecular Physics, and Optics ,Functional imaging ,chemistry ,Cone (topology) ,Retinal Cone Photoreceptor Cells ,Biomedical Imaging ,sense organs ,0210 nano-technology ,business - Abstract
Noninvasive, objective measurement of rod function is as significant as that of cone function, and for retinal diseases such as retinitis pigmentosa and age-related macular degeneration, rod function may be a more sensitive biomarker of disease progression and efficacy of treatment than cone function. Functional imaging of single human rod photoreceptors, however, has proven difficult because their small size and rapid functional response pose challenges for the resolution and speed of the imaging system. Here, we describe light-evoked, functional responses of human rods and cones, measured noninvasively using a synchronized adaptive optics optical coherence tomography (OCT) and scanning light ophthalmoscopy (SLO) system. The higher lateral resolution of the SLO images made it possible to confirm the identity of rods in the corresponding OCT volumes.
- Published
- 2020
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