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排序方式: 共有359条查询结果,搜索用时 250 毫秒
1.
Niya Narayanan Dukhabandhu Naik Jayaprakash Sahoo Sadishkumar Kamalanathan 《World Journal of Virology》2022,11(6):399-410
Coronavirus disease 2019 (COVID-19) is associated with a high risk of mortality and complications in patients with diabetes mellitus. Achieving good glycemic control is very important in diabetic patients to reduce complications and mortality due to COVID-19. Recent studies have shown the mortality benefit and anti-inflammatory effects of Dipeptidyl-peptidase-4 inhibitors (DPP-4i) in diabetic patients with COVID-19. DPP-4i may have a beneficial role in halting the severity of infection primarily by three routes, namely viral entry inhibition, anti-inflammatory and anti-fibrotic effects and glycemic control. This has raised the pro-mising hypothesis that DPP-4i might be an optimal strategy for treating COVID-19 in patients with diabetes. This review aims to summarise the possible therapeutic non-glycemic effects of DPP-4i in diabetic patients diagnosed with COVID-19 in the light of available evidence. 相似文献
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Sreenarasimhaiah J Jaramillo A Crippin J Lisker-Melman M Chapman WC Mohanakumar T 《Human immunology》2003,64(2):224-230
Chronic hepatitis C virus (HCV) infection develops in 85% of exposed individuals and 20% develop cirrhosis. However, the pathogenesis of this process is not well-understood. The objective of this study was to determine whether HCV-reactive T cells play a role in the process of development of cirrhosis during chronic HCV infection. We analyzed 21 human leukocyte antigen (HLA)-A2 patients with chronic HCV infection (9 with histology of inflammation and 12 with histology of fibrosis/cirrhosis). The frequency of CD8(+) T cells reactive to 12 HCV-derived epitopes was determined by an interferon-gamma enzyme-linked immunospot (ELISPOT) assay. The frequency of CD4(+) Th1 and Th2 cells reactive to the HCV core antigen was determined by interferon-gamma and interleukin-5 ELISPOT assays, respectively. Patients with histology of inflammation showed a significantly higher CD8(+) T-cell response to five HCV-derived epitopes (YLLPRRGPRL [core], CINGVCWTV [NS3], LLCPAGHAV [NS3], ILAGYGAGV [NS4B], and GLQDCTMLV [NS5B]) as compared with patients with histology of fibrosis/cirrhosis. Also, patients with histology of inflammation showed a significantly higher CD4(+) Th1 response to the HCV core antigen as compared to patients with histology of fibrosis/cirrhosis. These results indicate that a lack of an optimal T-cell response to HCV is associated with the development of cirrhosis during chronic HCV infection. 相似文献
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Cell proliferation is an important biological aspect of a tumor cell population which can affect clinical outcome. In addition to other well established clinical and histopathological prognostic criteria? cell kinetic data have significant predictive value. This study evaluates the proliferative activity of benign, premalignant and malignant cervical tissue by analyzing the expression of the proliferating cell nuclear antigen (PCNA). PCNA is a 36 kD nuclear protein associated with the cell cycle and is directly involved in DNA synthesis during cell proliferation. A total of 122 subjects were included in the study. This included 30 benign tissue samples, 30 low grade lesions (CIN 1), 30 high grade lesions (CIN 2/3) and 32 invasive squamous carcinomas. There was significant difference in PCNA index between benign and high grade lesions as well as benign and invasive cancer. The percentage of PCNA positive cells were significantly higher in invasive carcinoma when compared with non malignant lesions. Moreover, there was also good correlation between increasing histological abnormality and PCNA expression. These results suggest that cell proliferation index as detected by PCNA expression may be useful in the evaluation of alterations in cell kinetics of various grades of cervical lesions. Such data could also possibly help explain the biological behaviour of these lesions and be useful in planning of radiotherapy for invasive cervical cancer. 相似文献
6.
Jayaprakash Aravindakshan Valérie Paquet Mary Gregory Julie Dufresne Michel Fournier David J Marcogliese Daniel G Cyr 《Toxicological sciences》2004,78(1):156-165
There is limited information on the physiological consequences associated with exposure to xenoestrogens under field conditions. The objectives of this study were to determine the presence of estrogenic chemicals in the St. Lawrence River and their effects on male reproduction in the spottail shiner (Notropis hudsonius). Hepatic vitellogenin (VTG) mRNA levels in immature shiners indicate extensive estrogenic contamination spanning almost 50 km both upstream and downstream from the island of Montreal. Stages of spermatogenesis were assessed in fish captured at sites having varying levels of estrogenic contamination. In control fish, 95% had testis of either stage IV (50%) or stage V (45%) of spermatogenesis. At Ile Dorval, where VTG mRNA levels are moderate, fish had testes of stage III (38%) and IV (45%) and only 15% of fish were at spermatogenic stage V. In contrast, at Ilet Vert and Ile Beauregard, located in the sewage effluent plume from the City of Montreal and where hepatic VTG mRNA levels are high in fish, none of the fish were at stage V and 8% of fish at Ilet Vert were at stage II of development. Sperm concentration and various motility parameters were significantly lower in shiners from Ilet Vert as compared with those from Iles de la Paix (reference). Histological analyses of testes revealed that more than one-third of the fish captured at sites with the highest estrogenic contamination displayed intersex, a condition in which ovarian follicles were developing within the testis. These data indicate that there is significant estrogenic contamination in the St. Lawrence River that is associated with impaired reproductive function in male fish. 相似文献
7.
Philipp Saiko Geraldine Graser Benedikt Giessrigl Andreas Lackner Michael Grusch Georg Krupitza Arijit Basu Barij Nayan Sinha Venkatesan Jayaprakash Walter Jaeger Monika Fritzer-Szekeres Thomas Szekeres 《Biochemical pharmacology》2011,(1):50
Ribonucleotide reductase (RR; EC 1.17.4.1) is responsible for the de novo conversion of ribonucleoside diphosphates into deoxyribonucleoside diphosphates, which are essential for DNA replication. RR is upregulated in tumor cells and therefore considered to be an excellent target for cancer chemotherapy.ABNM-13 (N-hydroxy-2-(anthracene-2-yl-methylene)-hydrazinecarboximidamide), a novel N-hydroxy-N′-aminoguanidine has been designed to inhibit RR activity using 3D molecular space modeling techniques. In this study, we evaluated its effect on human HL-60 promyelocytic leukemia cells. ABNM-13 proved to be a potent inhibitor of RR which was displayed by significant alterations of deoxyribonucleoside triphosphate (dNTP) pool balance and a highly significant decrease of incorporation of radiolabeled cytidine into DNA of HL-60 cells. Diminished RR activity caused replication stress which was consistent with activation of Chk1 and Chk2, resulting in downregulation/degradation of Cdc25A. In contrast, Cdc25B was upregulated, leading to dephosphorylation and activation of Cdk1. The combined disregulation of Cdc25A and Cdc25B was the most likely cause for ABNM-13 induced S-phase arrest. Finally, we combined ABNM-13 with the first-line antileukemic agent arabinofuranosylcytosine (Ara-C) and found that ABNM-13 synergistically potentiated the antineoplastic effects of Ara-C.Due to these promising results, ABNM-13 deserves further preclinical and in vivo testing. 相似文献
8.
Jayaprakash Madhu Agilan Santhanam Muthukumarasamy Natarajan Dhayalan Velauthapillai 《RSC advances》2022,12(36):23221
In this work, zeolite NaA (RA) and NaX (RX) have been successfully synthesized using rice husk ash and it is a low cost synthesis process and it does not produce environmental hazards. Sodium silicate (SS) is extracted from rice husk ash which is an alternative silica source for zeolite synthesis. The zeolites are prepared by using a SS silica source extracted from the rice husk ash, and it has been used as an adsorbent for the CO2 adsorption process which may help in controlling the global warming problems. The zeolites are synthesized by a hydrothermal method without using any organic templating agent. FESEM and TEM micrographs revealed that the synthesized zeolites RA and RX have “Ice cube” and octahedral morphology respectively. From the N2 sorption studies, the BET surface area of the synthesized zeolites have been found and are 106.25 m2 g−1 and 512.79 m2 g−1 respectively. The maximum CO2 adsorption capacities of zeolite RA and RX are 2.22 and 2.45 mmol g−1, respectively at a temperature of 297.15 K. The recorded data are fitted by using non-linear adsorption isotherm models of Langmuir, Freundlich and Toth isotherm models. The fitted isotherm models are observed to be a type I adsorption isotherm according to the IUPAC classification criterion.In this work, zeolite NaA (RA) and NaX (RX) have been successfully synthesized using rice husk ash as source and it is a low cost synthesis process and it does not produce any environmental hazards. 相似文献
9.
Paramaguru Rathinavelusamy Dinakar Sasmal Venkatesan Jayaprakash 《Pharmaceutical biology》2014,52(2):199-207
Context: Pterospermum acerifolium (L.) Willd (Sterculiaceae) has been traditionally used in the treatment of diabetes mellitus but no scientific data has been published supporting the claimed ethnomedical use.Objective: The present study was designed to estimate the in silico, in vitro α-amylase inhibition potential and anti-diabetic activity of Pterospermum acerifolium bark.Materials and methods: In silico studies were performed between human pancreatic α-amylase (HPA) and β-sitosterol by using autodock 4.2 software. In vitro α-amylase inhibition study was carried out with 50% ethanol extract of the bark (PABEE) and its various fractions. The active ethyl acetate fraction (PABEF) was sub-fractionated into three fractions (PABE1, PABE2 and PABE3). Two doses (15 and 30?mg/kg) based on acute toxicity studies, of the above fractions were subjected to antidiabetic screening in vivo by STZ-nicotinamide induced type II diabetic rats.Results: In silico studies showed the potent inhibition of β-sitosterol on human pancreatic amylase (HPA) with an estimated inhibition constant (Ki) of 269.35?nmol and two hydrogen bond interactions. PABEF showed marked α-amylase inhibition (69.94%) compared to other fractions. Diabetic rats treated with PABE3 (30?mg/kg) reduced the levels of fasting blood glucose, HbA1c, ALT, AST, ALP, triglycerides, total cholesterol, TBARS significantly (p?0.01) and increased the levels of HDL-C, catalase, GSH, SOD significantly (p?0.01) as compared to that of diabetic control animals. Histological studies on PABE3 treated group showed remarkable positive changes in β-cells.Conclusion: The present study confirmed the antihyperglycemic activity along with its status on hepatic biomarkers, antihyperlipidemic and antioxidant properties of Pterospermum acerifolium bark. 相似文献
10.
Sreeja L Syamala VS Syamala V Hariharan S Raveendran PB Vijayalekshmi RV Madhavan J Ankathil R 《Journal of cancer research and clinical oncology》2008,134(6):645-652
Purpose Inter individual variation in lung cancer susceptibility may be modulated in part through genetic polymorphisms in the DNA
repair genes, especially the genes involved in the Base Excision Repair (BER) and nucleotide excision repair (NER) pathway.
Two of the genetic polymorphisms, XRCC1Arg399Gln and XPD Lys751Gln have been extensively studied in the association with lung
cancer risk, although published studies have been inconclusive.
Methods In order to verify the role of the common variant alleles in the XPD gene, we have genotyped 211 lung cancer patients and
211 healthy controls using PCR-RFLP assays in a hospital based, case-control study in an Indian population. Logistic regression
models were fit to examine the relationship between the log odds of lung cancer and each covariate. Overall Survival in relation
to various genotypes and clinicopathological factors were analyzed using Kaplan Meier estimates and hazard ratios were calculated
using Cox Regression analysis.
Results The carriers of XRCC1 399 AA genotypes were at higher risk of lung cancer (OR = 2.1, 95% CI:1.224–3.669, P = 0.007) than carriers
of GG genotype. Subjects carrying 751 AC genotype were at an increased risk of carcinoma of the lung (OR = 1.8; 95% CI:1.233–2.807,
P = 0.003) than subjects with AA genotypes. Compared to the XRCC1 399 GG/ XPD 751 AA reference genotype, the combined variants,
XRCC1 399 GG/ XPD 751 AC+CC (OR = 1.9, 95% CI: 1.037–3.481), P = 0.03), XRCC1 399 GA+AA/ XPD 751 AA (OR = 1.7, 95% CI: 1.020–2.833,
P = 0.04), XRCC1 399 GA+AA/XPD 751 AC+CC (OR = 2.7, 95% CI: 1.582–4.864, P = 0.01), had significantly higher odds ratios.
Increasing numbers of either XPD or XRCC1 variant alleles were associated with shorter overall survival, the risk being significant
for the XRCC1 gene polymorphism (P = 0.01 by log-rank test). The hazard of dying was significant for the XRCC1 399 AA genotype
(HR = 3.04, 95%CI: 1.393–6.670, P = 0.005). Higher tumour stage also came out as significant predictors of patient death.
Conclusions These findings suggest that genetic polymorphisms in the DNA repair genes may modulate overall lung cancer susceptibility
and that pathological stage and XRCC1 Arg399Gln independently predicted overall survival among Indian lung cancer patients. 相似文献