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Bhatt D, Stan RC, Pinhata R, Machado M, Maity S, Cunningham‐Rundles C, Vogel C, de Camargo MM. Chemical chaperones reverse early suppression of regulatory circuits during unfolded protein response in B cells from common variable immunodeficiency patients. Clin Exp Immunol 2020; 200:73-86. [PMID: 31859362 PMCID: PMC7066380 DOI: 10.1111/cei.13410] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/15/2019] [Indexed: 12/19/2022] Open
Abstract
B cells orchestrate pro-survival and pro-apoptotic inputs during unfolded protein response (UPR) to translate, fold, sort, secrete and recycle immunoglobulins. In common variable immunodeficiency (CVID) patients, activated B cells are predisposed to an overload of abnormally processed, misfolded immunoglobulins. Using highly accurate transcript measurements, we show that expression of UPR genes and immunoglobulin chains differs qualitatively and quantitatively during the first 4 h of chemically induced UPR in B cells from CVID patients and a healthy subject. We tested thapsigargin or tunicamycin as stressors and 4-phenylbutyrate, dimethyl sulfoxide and tauroursodeoxycholic acid as chemical chaperones. We found an early and robust decrease of the UPR upon endoplasmic reticulum (ER) stress in CVID patient cells compared to the healthy control consistent with the disease phenotype. The chemical chaperones increased the UPR in the CVID patient cells in response to the stressors, suggesting that misfolded immunoglobulins were stabilized. We suggest that the AMP-dependent transcription factor alpha branch of the UPR is disturbed in CVID patients, underlying the observed expression behavior.
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Verma S, Qiuhe J, Bhatt D, Mazer C, Al-Omran M, Inzucchi S, Wanner C, Ofstad A, Zwiener I, George J, Zinman B, Fitchett D. URIC ACID LEVELS PREDICT CARDIORENAL OUTCOMES AND CARDIOVASCULAR DEATH IN PATIENTS WITH TYPE 2 DIABETES: A SUB-ANALYSIS OF EMPA-REG OUTCOME. Can J Cardiol 2019. [DOI: 10.1016/j.cjca.2019.07.554] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
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Berg D, Wiviott S, Scirica B, Gurmu Y, Mosenzon O, Murphy S, Bhatt D, Leiter L, McGuire D, Wilding J, Johansson P, Langkilde A, Raz I, Braunwald E, Sabatine M. 410Heart failure risk stratification and efficacy of dapagliflozin in patients with type 2 diabetes mellitus. Eur Heart J 2019. [DOI: 10.1093/eurheartj/ehz747.0105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Abstract
Background
Patients with type 2 diabetes mellitus (T2DM) are at increased risk of developing heart failure (HF). Treatment with sodium-glucose cotransporter-2 (SGLT2) inhibitors reduces the risk of hospitalization for HF (HHF) in patients with T2DM.
Purpose
To develop and validate a practical, multivariable clinical risk score for HHF in patients with T2DM and assess whether this score can identify high-risk patients with T2DM who have the greatest reduction in risk for HHF with an SGLT2 inhibitor.
Methods
We developed a clinical risk score for centrally-adjudicated HHF using independent clinical risk indicators of HHF in 8212 patients with T2DM in the placebo arm of SAVOR-TIMI 53. Candidate variables were assessed using multivariable Cox regression and independent clinical risk indicators achieving statistical significance of p<0.001 were included in the risk score and given weights proportional to the regression coefficients. We externally validated the score in 8578 patients with T2DM in the placebo arm of DECLARE-TIMI 58. Discrimination was assessed using Harrell's c-index. The relative and absolute risk reductions in HHF with the SGLT2 inhibitor dapagliflozin were assessed by baseline HHF risk.
Results
The 5 independent clinical risk indicators were prior heart failure, atrial fibrillation, coronary artery disease, estimated glomerular filtration rate (eGFR), and urine albumin/creatinine ratio (UACR) (Figure, left). A simple integer-based scheme using these predictors identified a strong >16-fold gradient of HHF risk (p-trend <0.001) in both the derivation and validation cohorts, with c-indices of 0.81 and 0.78, respectively. Whereas relative risk reductions were similar across the risk score (25–34%), absolute risk reductions were greater in those at higher baseline risk (interaction p-value for absolute risk reduction <0.01), with high-risk (2 points) and very high-risk patients (≥3 points) having 1.5% and 2.7% absolute risk reductions in HHF at 4 years with dapagliflozin, translating into NNTs of only 65 and 36, respectively (Figure, right).
Conclusion(s)
Risk stratification using a novel clinical risk score for HHF in patients with T2DM identifies patients at higher risk for HHF who derive greater benefit from treatment with the SGLT2 inhibitor dapagliflozin.
Acknowledgement/Funding
SAVOR-TIMI 53 and DECLARE-TIMI 58 were sponsored by AstraZeneca.
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Bhardwaj N, Bhardwaj SK, Bhatt D, Lim DK, Kim KH, Deep A. Optical detection of waterborne pathogens using nanomaterials. Trends Analyt Chem 2019. [DOI: 10.1016/j.trac.2019.02.019] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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30
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Al-Omran M, Salata K, Hussain M, de Mestral C, Greco E, Tu J, Mamdani M, Forbes T, Bhatt D, Verma S. PO297 Time-series Analysis of Elective and Ruptured Abdominal Aortic Aneurysm Repair Trends From 2003 to 2016. Glob Heart 2018. [DOI: 10.1016/j.gheart.2018.09.239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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31
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Bhatt D, Gupta E, Kaushik S, Srivastava VK, Saxena J, Jyoti A. Bio-fabrication of silver nanoparticles by Pseudomonas aeruginosa: optimisation and antibacterial activity against selected waterborne human pathogens. IET Nanobiotechnol 2018; 12:981-986. [PMID: 30247141 PMCID: PMC8676076 DOI: 10.1049/iet-nbt.2018.0051] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2018] [Revised: 04/19/2018] [Accepted: 05/04/2018] [Indexed: 11/20/2022] Open
Abstract
Multiple drug resistance and treatment of contaminated water has become a serious issue in past years. Silver nanoparticles (AgNPs), being bactericidal, non-toxic, cheap and environment friendly behaviour, have drawn attention to overcome these problems. This study has been designed to synthesise AgNPs from Pseudomonas aeruginosa. AgNPs formation was confirmed by colour change and UV-vis spectroscopy. Furthermore, Fourier transform infrared spectroscopy peaks demonstrated the presence of capped proteins as reducing and stabilising agent. Transmission electron microscopy micrograph revealed spherical shape AgNPs with the size ranging between 10 and 20 nm. Antibacterial activity of AgNPs was evaluated against the most prevalent waterborne pathogens enterohaemorrhagic Escherichia coli and Salmonellae typhimurium. Moreover, the antibacterial activity of AgNPs was tested for the treatment of contaminated water which showed attenuation in bacterial load within 8 h as demonstrated by growth kinetics data. Furthermore, AgNPs did not exhibit haemolytic effects on human red blood cells (RBCs) even at 100 mg L-1 concentration of AgNPs. The results herein suggest that AgNPs synthesised by P. aeruginosa under optimised conditions exhibit microbicidal property against waterborne pathogens and having no toxic effect on human RBCs. These AgNPs could be employed for treatment of contaminated water after process optimisation.
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Verma S, Leiter L, Mazer C, Bain S, Buse J, Marso S, Nauck M, Zinman B, Bosch-Traberg H, Frimer-Larsen H, Michelsen M, Bhatt D. LIRAGLUTIDE REDUCES CARDIOVASCULAR EVENTS AND MORTALITY IN TYPE 2 DIABETES INDEPENDENT OF LDL CHOLESTEROL AND STATIN USE: RESULTS OF THE LEADER TRIAL. Can J Cardiol 2018. [DOI: 10.1016/j.cjca.2018.07.220] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022] Open
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33
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Verma S, Mazer C, Bhatt D, Raj S, Yan A, Verma A, Ferrannini E, Simons G, Lee J, Zinman B, George J, Fitchett D. EMPAGLIFLOZIN REDUCES MORTALITY IN PATIENTS WITH TYPE 2 DIABETES AND A HISTORY OF LEFT VENTRICULAR HYPERTROPHY: A SUB-ANALYSIS OF THE EMPA-REG OUTCOME TRIAL. Can J Cardiol 2018. [DOI: 10.1016/j.cjca.2018.07.353] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022] Open
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34
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White H, Steg P, Szarek M, Bhatt D, Bittner V, Diaz R, Edelberg J, Goodman S, Hantoin C, Harrington R, Jukema J, Lecorps G, Moryusef A, Pordy R, Roe M, Zeiher A, Schwartz G. Cardiovascular Outcomes With Alirocumab After Acute Coronary Syndrome: Results of the Odyssey Outcomes Trial. Heart Lung Circ 2018. [DOI: 10.1016/j.hlc.2018.06.585] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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35
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Yanagawa B, Mazine A, Tam D, Juni P, Bhatt D, Spindel S, Puskas J, Verma S, Friedrich J. HOMOGRAFT VERSUS CONVENTIONAL PROSTHESIS FOR SURGICAL MANAGEMENT OF AORTIC VALVE INFECTIVE ENDOCARDITIS A SYSTEMATIC REVIEW AND META-ANALYSIS. Can J Cardiol 2017. [DOI: 10.1016/j.cjca.2017.07.080] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
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36
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Prabakar C, Tang N, Nematian S, Hosseini NS, Bhatt D, Homel P, Bral P. The Utility of the Transverse Abdominus Plane (TAP) Block in Minimally Invasive Gynecologic Surgery: A Randomized Double Blinded Clinical Trial. J Minim Invasive Gynecol 2016; 22:S76. [PMID: 27679333 DOI: 10.1016/j.jmig.2015.08.203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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37
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Irani M, Seifer D, Grazi R, Bhatt D, Julka N, Kalgi B, Irani S, Tal O, Tal R. Vitamin D supplementation decreases TGF beta-1 bioavailability correlating with clinical improvement in Vitamin D deficient women with PCOS: a randomized placebo-controlled trial. Fertil Steril 2015. [DOI: 10.1016/j.fertnstert.2015.07.324] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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38
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Uldall M, Bhatt D, Kruuse C, Juhler M, Jansen-Olesen I, Jensen R. EHMTI-0077. Obesity-related intracranial hypertension in the rat – a possible idiopathic intracranial hypertension (IIH) model? J Headache Pain 2014. [PMCID: PMC4181892 DOI: 10.1186/1129-2377-15-s1-f29] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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39
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Prabakar C, Irani M, Julka N, Bhatt D, Homel P, Saraf S, Bral P. What Your Patient Does Not Know: A Survey of Patient Knowledge about Surgical Approaches in Gynecology. J Minim Invasive Gynecol 2014. [DOI: 10.1016/j.jmig.2014.08.431] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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40
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Bhatt D, Chauhan N, Sharma A, Dhawan D, Bhatt RV, Phatak S, Padh H. Investigating the Role of Plasma Glucose Concentration as a Phenotypic Marker for CYP2C9 Genetic Variants, in the Diabetic Population of Gujarat. Indian J Pharm Sci 2014; 76:72-7. [PMID: 24799741 PMCID: PMC4007258] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2013] [Revised: 12/19/2013] [Accepted: 12/26/2013] [Indexed: 12/02/2022] Open
Abstract
The present study was aimed to investigate the role of plasma glucose concentration as a phenotypic marker and to study the frequency distribution of CYP2C9 genetic variants in Gujarat state diabetic population. One hundred and nine unrelated diabetes mellitus patients treated with sulfonylureas were genotyped for CYP2C9*2 and CYP2C9*3 alleles. Their pre- and posttreatment postprandial blood glucose levels were recorded and mean glucose drop per milligram of drug values were calculated and further used as an index for phenotypic correlation. The frequencies of CYP2C9*1, CYP2C9*2 and CYP2C9*3 alleles in the Gujarat state diabetic population were 0.84, 0.07 and 0.09, respectively. The distribution of CYP2C9*1/*1, CYP2C9*1/*2, CYP2C9*1/*3, CYP2C9*2/*2, CYP2C9*2/*3 and CYP2C9*3/*3 genotypes were 0.73, 0.08, 0.13, 0.0, 0.06 and 0.0, respectively. Patients with CYP2C9*1/*2 genotype did not show any significant difference in the mean glucose drop per milligram of drug values when compared with wild-type patients in glipizide-treatment group. Patients with CYP2C9*1/*3 genotype showed greater mean glucose drop per milligram of drug values than patients with CYP2C9*1/*1 wild-type genotype for both glipizide and glimepiride while patients with CYP2C9*2/*3 genotype showed greater drop than patients with CYP2C9*1/*1 genotype only in the glipizide-treatment group. The presence of CYP2C9*3 allele significantly affected plasma glucose drop per milligram of drug values in patients taking glipizide and glimepiride, while effects of CYP2C9*2 allele were insignificant. Further studies are needed to confirm the effects of CYP2C9*2 allele on plasma glucose drop per milligram of drug values. However, plasma glucose concentration is a complex physiological marker that cannot be used to establish perfect genotype-phenotype correlation. Hence studies exploring robust phenotypic markers must be initiated.
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Chiquete E, Ruiz-Sandoval J, Rodriguez-Balaguer R, Magana-Zamora L, Saniger-Alba M, Gonzalez-Duarte A, Garcia-Ramos G, Ramos A, Steg PG, Bhatt D, Cantu-Brito C. Four-Year Changing Patterns in Prescription of Anti-Atherothrombotic Drugs in the Latin American Cohort of the Worldwide Reduction of Atherothrombosis for Continued Health (REACH) Registry (P01.039). Neurology 2012. [DOI: 10.1212/wnl.78.1_meetingabstracts.p01.039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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42
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Cashman DJ, Mamonov AB, Bhatt D, Zuckerman DM. Thermal motions of the E. coli glucose-galactose binding protein studied using well-sampled, semi-atomistic simulations. Curr Top Med Chem 2011; 11:211-20. [PMID: 20939787 DOI: 10.2174/156802611794863607] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2009] [Accepted: 04/14/2010] [Indexed: 11/22/2022]
Abstract
The E. coli glucose-galactose chemosensory receptor is a 309 residue, 32 kDa protein consisting of two distinct structural domains. We used two computational methods to examine the protein's thermal fluctuations, including both the large-scale interdomain movements that contribute to the receptor's mechanism of action, as well as smaller-scale motions. We primarily employ extremely fast, "semi-atomistic" Library-Based Monte Carlo (LBMC) simulations, which include all backbone atoms but "implicit" side chains. Our results were compared with previous experiments and all-atom molecular dynamics (MD) simulation. Both LBMC and MD simulations were performed using both the apo and glucose-bound form of the protein, with LBMC exhibiting significantly larger fluctuations. The LBMC simulations are in general agreement with the disulfide trapping experiments of Careaga & Falke (J. Mol. Biol., 1992, Vol. 226, 1219-35), which indicate that distant residues in the crystal structure (i.e. beta carbons separated by 10 to 20 angstroms) form spontaneous transient contacts in solution. Our simulations illustrate several possible "mechanisms" (configurational pathways) for these fluctuations. We also observe several discrepancies between our calculations and experimental rate constants. Nevertheless, we believe that our semi-atomistic approach could be used to study fluctuations in other proteins, perhaps for ensemble docking or other analyses of protein flexibility in virtual screening studies.
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Ademi Z, Liew D, Hollingsworth B, Steg P, Bhatt D, Reid C. Cost Effectiveness of Aspirin Among Participants with Atherothrombotic Disease in Australian General Practice, Using “Real World” Data from the Australian REACH Registry. Heart Lung Circ 2010. [DOI: 10.1016/j.hlc.2010.06.721] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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44
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Lee JY, Bhatt D, Bhatt D, Chung WY, Cooper RL. Furthering pharmacological and physiological assessment of the glutamatergic receptors at the Drosophila neuromuscular junction. Comp Biochem Physiol C Toxicol Pharmacol 2009; 150:546-57. [PMID: 19695344 DOI: 10.1016/j.cbpc.2009.08.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2009] [Revised: 08/03/2009] [Accepted: 08/06/2009] [Indexed: 11/23/2022]
Abstract
Drosophila melanogaster larval neuromuscular junctions (NMJs) serve as a model for synaptic physiology. The molecular sequences of the postsynaptic glutamate receptors have been described; however, the pharmacological profile has not been fully elucidated. The postsynaptic molecular sequence suggests a novel glutamate receptor subtype. Kainate does not depolarize the muscle, but dampens evoked EPSP amplitudes. Quantal responses show a decreased amplitude and area under the voltage curve indicative of reduced postsynaptic receptor sensitivity to glutamate transmission. ATPA, a kainate receptor agonist, did not mimic kainate's action. The metabotropic glutamate receptor agonist t-ACPD had no effect. Domoic acid, a kainate/AMPA receptor agonist, blocks the postsynaptic receptors without depolarizing the muscle. However, SYM 2081, a kainate receptor agonist, did depolarize the muscle and reduce the EPSP amplitude at 1 mM but not at 0.1 mM. This supports the notion that these are generally a quisqualate subtype receptors with some oddities in the pharmacological profile. The results suggest a direct postsynaptic action of kainate due to partial antagonist action on the quisqualate receptors. There does not appear to be presynaptic auto-regulation via a kainate receptor subtype or a metabotropic auto-receptor. This study aids in furthering the pharmokinetic profiling and specificity of the receptor subtypes.
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Cooper RJ, Bhatt D, Everdell NL, Hebden JC. A tissue-like optically turbid and electrically conducting phantom for simultaneous EEG and near-infrared imaging. Phys Med Biol 2009; 54:N403-8. [DOI: 10.1088/0031-9155/54/18/n01] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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46
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Parhofer K, Röther J, Binz C, Schwertfeger M, Limbourg T, Bhatt D, Steg G, Krempf M, Zeymer U. Abstract: 1067 COMPARISON OF 2-YEAR EVENT RATES BETWEEN WESTERN AND EASTERN EUROPEAN DIABETICS WITH ESTABLISHED ATHEROTHROMBOSIS (RESULTS FROM THE REACH-REGISTRY). ATHEROSCLEROSIS SUPP 2009. [DOI: 10.1016/s1567-5688(09)70408-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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47
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Peacock W, Bhatt D, Diercks D, Amsterdam E, Chandra A, Ohman E, Brown D, Januzzi J. 93. Ann Emerg Med 2006. [DOI: 10.1016/j.annemergmed.2006.07.544] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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48
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Kumar A, Bhatt D. Vocal signals in a tropical Avian species, the redvented bulbul Pycnonotus cafer: their characteristics and importance. J Biosci 2000; 25:387-96. [PMID: 11120591 DOI: 10.1007/bf02703792] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Acoustic signals play an important role in the lives of birds. Almost all avian species produce vocal signals in a variety of contexts either in the form of calls or songs or both. In the present study different types of vocal signals of the tropical avian species Pycnonotus cafer were characterized on the basis of their physical characteristics and context of production. This species used six types of vocal signals: contact signals, roosting signals, alarm signals, twittering signals, distress signals and begging signals. Two types of alarm signals are produced based on predation pressure. These signals are dissimilar in all physical characteristics except for dominant frequency. Although alarm signal type I and roosting signals are phonetically similar, they have completely different sonogram characteristics.
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Abstract
Two chimeric enzymes were constructed by exchanging domains between porcine pepsinogen and rhizopuspepsinogen in order to examine the contributions of the subsites present on different domains toward enzymatic specificity. Both chimeras exhibited the characteristic features of aspartic proteinases, such as auto-activation at low pH and abrogation of enzymatic activity by pepstatin. The activity of the chimera containing the N-terminal domain of rhizopuspepsinogen and the C-terminal domain of porcine pepsinogen (rhzNppC) could be observed by HPLC after prolonged incubation with the substrates. In contrast, the reciprocal chimera, ppNrhzC, containing the N-terminal domain of porcine pepsinogen and the C-terminal domain of rhizopuspepsinogen exhibited catalytic activity, measurable by a spectrophotometric assay. Kinetic data and inhibitor analyses strongly suggest that interdependency may exist between adjacent subsites contributed by different domains. Therefore, in order to develop an optimal substrate or inhibitor, the effect of adjacent residues of the ligand has to be examined along with the preferences for each subsite.
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Kervinen J, Lubkowski J, Zdanov A, Bhatt D, Dunn BM, Hui KY, Powell DJ, Kay J, Wlodawer A, Gustchina A. Toward a universal inhibitor of retroviral proteases: comparative analysis of the interactions of LP-130 complexed with proteases from HIV-1, FIV, and EIAV. Protein Sci 1998; 7:2314-23. [PMID: 9827997 PMCID: PMC2143868 DOI: 10.1002/pro.5560071108] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
One of the major problems encountered in antiviral therapy against AIDS is the emergence of viral variants that exhibit drug resistance. The sequences of proteases (PRs) from related retroviruses sometimes include, at structurally equivalent positions, amino acids identical to those found in drug-resistant forms of HIV-1 PR. The statine-based inhibitor LP-130 was found to be a universal, nanomolar-range inhibitor against all tested retroviral PRs. We solved the crystal structures of LP-130 in complex with retroviral PRs from HIV-1, feline immunodeficiency virus, and equine infectious anemia virus and compared the structures to determine the differences in the interactions between the inhibitor and the active-site residues of the enzymes. This comparison shows an extraordinary similarity in the binding modes of the inhibitor molecules. The only exceptions are the different conformations of naphthylalanine side chains at the P3/P3' positions, which might be responsible for the variation in the Ki values. These findings indicate that successful inhibition of different retroviral PRs by LP-130 is achieved because this compound can be accommodated without serious conformational differences, despite the variations in the type of residues forming the active-site region. Although strong, specific interactions between the ligand and the enzyme might improve the potency of the inhibitor, the absence of such interactions seems to favor the universality of the compound. Hence, the ability of potential anti-AIDS drugs to inhibit multiple retroviral PRs might indicate their likelihood of not eliciting drug resistance. These studies may also contribute to the development of a small-animal model for preclinical testing of antiviral compounds.
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