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Palanisamy Venkatachalam Dharm Prakash Dwivedi Vishnukanth Govindraj 《The Indian journal of tuberculosis》2021,68(2):230-235
Background and objectiveChronic Obstructive Pulmonary Disease (COPD) causes substantial morbidity and mortality across the globe. Diagnosis of COPD requires post-bronchodilator FEV1/FVC <0.70 as per GOLD Guidelines. FVC maneuver requires a minimum of 6 seconds of forceful expiration with no flow for 1 second for an accepted effort, which lacks any fixed cut-off point. This leads to discomfort, especially in advanced COPD and old aged population. We conducted this study to find the utility of FEV1/FEV6 as a surrogate for FEV1/FVC, the correlation between the two ratios, and the fixed cut-off value of FEV1/FEV6 for COPD diagnosis.MethodsThis was a prospective, cross-sectional study approved by the institutional ethics committee conducted from January 2017 to November 2018. Consented patients above 18 years suspected of COPD underwent Spirometry as per ATS guidelines. FEV1, FEV6, FEV1/FEV6 and FEV1/FVC ratios were recorded from the best acceptable maneuver.ResultsOut of 560 screened patients, 122 diagnosed as COPD. The correlation coefficient between the post-bronchodilator FEV1/FVC ratio and FEV1/FEV6 ratio was 0.972 (p < 0.01). The relationship between the post-bronchodilator FEV1/FVC ratio and FEV1/FEV6 ratio (linear regression analysis) was found out as: FEV1/FVC = ?1.845 + 1.009(FEV1/FEV6). Using this formula, the post-bronchodilator FEV1/FEV6 value of 71.845 was obtained corresponding to the post-bronchodilator FEV1/FVC value of 70.00.ConclusionWe found a positive correlation coefficient (r = 0.972, p < 0.001) between the FEV1/FEV6 and FEV1/FVC ratios and the cut off value of 71.845 (p < 0.01) for the post-bronchodilator FEV1/FEV6 ratio for the diagnosis of COPD. Thus FEV1/FEV6 should be used as a surrogate for FEV1/FVC for the diagnosis of COPD. 相似文献
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Polymers, derived from bio-derived resources, have gained considerable momentum because of a lower dependence over conventional fossil-based resources without compromising the materials'' thermo-mechanical properties. Unique characteristics of organic and inorganic materials can be incorporated by a combination of both to obtain hybrid materials. We have recently developed a series of transparent biopolyimides (BPI) from a biologically derived exotic amino acid, 4-aminocinnamic acid (4ACA) to yield 4-amino truxillic ester (4ATA ester) derivatives. In the present research, the polyimide-precursor was subjected to sol–gel polycondensation reactions with silicon-alkoxide followed by annealing under vacuo to yield a biopolyimide-silica hybrid. The biopolyimide structures (4ATA acid/ester) and their silica hybrids thermo-mechanical, electrical and optical performance were evaluated. It was found that the biopolyimide with 4ATA(ester) yields thermo-mechanically robust films with very high electrical stability as well as optical transparency, plausibly due to the uniform dispersion of the silica particles in the biopolyimide matrix.Biopolyamide structure and their silica hybrids performances were studied. Biopolyamide with inability to interact with silanol during sol–gel condensation for silica formation showed superior thermo-mechanical, optical and electrical properties. 相似文献
24.
Evidence for activation of cellular immune responses in patients with acute hepatitis E. 总被引:1,自引:0,他引:1
Sita Naik Rakesh Aggarwal Subhash R Naik Sunita Dwivedi Sudha Talwar S K Tyagi S D Duhan P Coursaget 《Indian journal of gastroenterology》2002,21(4):149-152
INTRODUCTION: Although acute hepatitis E virus (HEV) infection is known to induce IgM and IgG humoral host immune responses, little is known about occurrence of cellular responses in this infection. We looked for evidence of lymphocyte sensitization to HEV peptides in patients with acute HEV infection. METHODS: peripheral blood lymphocytes were obtained from patients with acute hepatitis E and healthy controls. Proliferation of these lymphocytes in the presence of each of seven peptides with amino acid sequences corresponding to open reading frames 2 and 3 proteins of HEV (3 and 4 peptides, respectively) were studied; no peptide was added to control wells. Proliferative responses with stimulation indices exceeding 3.0 were taken as positive. RESULTS: More patients showed reactivity to two or more HEV peptides than did controls (11/21 vs 5/22, p<0.05). Reactivity to one peptide corresponding to open reading frame 2 of HEV was more frequent in patients than in controls (7/21 vs 1/22, p<0.05). CONCLUSION: Our results show that lymphocytes of patients with acute hepatitis E show sensitization to HEV peptides. This may have significance in understanding the pathogenetic mechanisms of liver injury in this infection. 相似文献
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Sandeep Kumar Alok Kumar Verma Mukul Das Premendra D. Dwivedi 《Immunology letters》2013,149(1-2):101-109
Food allergy is an immune provocation induced by certain food in susceptible individuals. Most of the food allergic manifestations are evident in the individual having impaired oral tolerance. In spite of worldwide prevalence, there is no permanent cure of food allergy. Food allergic reactions are complex immunological events that comprises of several immune molecules like IgE, IL-4, IL-13 and T-cells, therefore, researchers are trying to pick the correct molecule to find out pivotal therapeutic solutions. Being a key regulatory molecule in suppressing T-cells functional activities, cytotoxic T-cell lymphocyte antigen-4 (CTLA-4) or cluster of differentiation-152 (CD-152) has contributed a novel and revolutionary dimension toward therapeutic research of several diseases. This review focuses on different immunological and mechanistic perspectives of CTLA-4 in correlation with food allergy. 相似文献
27.
Stress plays a major role in inducing depression, which may arise from interplay between complex cascades of molecular and cellular events that influence gene expression leading to altered connectivity and neural plasticity. In recent years, microRNAs (miRNAs) have carved their own niche owing to their innate ability to induce disease phenotype by regulating expression of a large number of genes in a cohesive and coordinated manner. In this study, we examined whether miRNAs and associated gene networks have a role in chronic corticosterone (CORT; 50 mg kg−1 × 21 days)-mediated depression in rats. Rats given chronic CORT showed key behavioral features that resembled depression phenotype. Expression analysis revealed differential regulation of 26 miRNAs (19 upregulated, 7 downregulated) in prefrontal cortex of CORT-treated rats. Interaction between altered miRNAs and target genes showed dense interconnected molecular network, in which multiple genes were predicated to be targeted by the same miRNA. A majority of altered miRNAs showed binding sites for glucocorticoid receptor element, suggesting that there may be a common regulatory mechanism of miRNA regulation by CORT. Functional clustering of predicated target genes yielded disorders such as developmental, inflammatory and psychological that could be relevant to depression. Prediction analysis of the two most prominently affected miRNAs miR-124 and miR-218 resulted into target genes that have been shown to be associated with depression and stress-related disorders. Altogether, our study suggests miRNA-mediated novel mechanism by which chronic CORT may be involved in depression pathophysiology. 相似文献
28.
Regulation of the gene for renal 25-hydroxyvitamin D-24-hydroxylase (CYP24) is important for controlling the level of circulating 1,25-dihydroxyvitamin D3 (1,25(OH)2D3). We report here for the first time that the peptide hormone calcitonin significantly stimulates expression of a rat CYP24 promoter-luciferase construct in both transiently and stably transfected kidney HEK-293 cells. A GC box at -114/-101 and a CCAAT box at -62/-51 have been identified that underlie both basal expression of the CYP24 promoter and the calcitonin inductive response. Data from overexpression studies suggested that Sp1 and NF-Y are the proteins that function through the GC and CCAAT boxes respectively. ERK1/2 signaling pathways were not involved in the calcitonin-mediated response, since stimulation of the promoter was unaffected by the pharmacological ERK1/2 inhibitor PD98059 and by a dominant negative mutant of ERK1/2 (ERK1K71R). In contrast, calcitonin induction but not basal expression was dependent on protein kinase A and protein kinase C (PKC) activities with the inhibitors H89 and calphostin C lowering induction by 50-60%. The atypical PKC, PKCzeta contributes to calcitonin induction, but not to basal expression of the CYP24 promoter, since overexpression of a dominant negative clone PKCzetaK281 M lowered induction by 50%. Cotransfection of a dominant negative form of Ras resulted in calcitonin-mediated induction being reduced also by about 50%. A Ras-PKCzeta signaling pathway for calcitonin action is proposed, which acts through the GC box. The findings have been extrapolated to the in vivo situation where we suggest that induction of renal CYP24 by calcitonin could be important under hypercalcemic conditions thus contributing to the lowering of circulating 1,25(OH)2D3 levels. 相似文献
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