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31.
Radhakrishnan Chandraprabha Vineetha Viswanathan Archana Prakash Binu Pettamanna Arathi 《Nutrition and cancer》2018,70(4):684-696
Arsenic trioxide (As2O3) is a promising new regimen for the treatment of acute promyelocytic leukemia (APL). The induction of oxidative stress mediated by reactive oxygen species (ROS) and excessive intracellular calcium influx are the main reasons behind As2O3 toxicity. Since liver is the major organ for xenobiotic metabolism, it is always under stress. Antioxidant vitamins such as L-Ascorbic acid (L-AA) and α-Tocopherol (α-TOC) have been proposed to have beneficial effects against a variety of pathological conditions and are known by their free radical scavenging properties. The present study evaluates the curative efficacy of L-AA and α-TOC against As2O3 toxicity using immortalized human Chang liver cells. Our results suggest that L-AA (100 µM) and α-TOC (50 µM) recovered As2O3 (10 µM) cytotoxicity. Furthermore, As2O3 treatment showed an increase in lipid peroxidation and depletion in antioxidant status, mitochondrial trans membrane potential and values of total antioxidant capacity. Cotreatment of antioxidant vitamins with As2O3 resulted in a significant reversal of oxidative stress markers. Our findings substantiate the effect of antioxidant vitamins in protecting the hepatocytes from oxidative stress which may be attributed through Nrf2 (Nuclear factor erythroid 2-related factor 2) mediated upregulation of Bcl2 (B-cell lymphoma 2) expression. 相似文献
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J. Dinakaran Mohammad Hanief Archana Meena K. S. Rao 《Proceedings of the National Academy of Sciences, India. Section B.》2014,84(3):487-504
According to Kyoto protocol carbon sequestration in terrestrial ecosystem is a low cost option to mitigate the increasing atmospheric CO2 concentrations. It has been understood that the world’s forests and their soils have a high potential to sequester the atmospheric carbon. For the last two decades there has been increasing interest among scientists in terrestrial soil carbon storage processes. This review made an attempt to summarize the major chronological advancement of soil organic carbon (SOC) sequestration research and also to underpin the problems yet to be focused on this research at global level. SOC sequestration research began in the early seventies, where most of the studies were estimating the size/stock of the global SOC. In the early eighties, most of the researchers have started to focus on the factors involved in the storage of organic carbon in different ecosystems. Subsequently, the researchers started to work on different types of SOC pools, their size, turnover and chemical characterization in different types of ecosystems. Recently the researcher’s main focus has been the temperature sensitivity of organic carbon in different types of soil and their mechanism of stabilization. There has been interest among researchers on the contribution of microbial derived (microbial necromass) carbon in recalcitrant pool of SOC and their sequestration process in different types of ecosystems. Arguably, the contribution in SOC sequestration research on the fate of sequestered carbon in different types of soil and their stabilization mechanisms is insufficient. India is the country spread over regions from temperate to dry desert zones with different types of fragile ecosystems and its vulnerable nature to the global climate change. Therefore, the future research must focus on SOC sensitivity to temperature and SOC stabilization mechanisms in different ecosystems for better understanding of the soil carbon cycle. 相似文献
35.
Hui Yu Zhengming Chen Karla V. Ballman Mark A. Watson Ramaswamy Govindan Irena Lanc David G. Beer Raphael Bueno Lucian R. Chirieac Michael Herman Chui Guoan Chen Wilbur A. Franklin David R. Gandara Carlo Genova Kristine A. Brovsky Mary-Beth M. Joshi Daniel T. Merrick William G. Richards Fred R. Hirsch 《Journal of thoracic oncology》2019,14(1):25-36
Objectives
Anti–programmed cell death 1 (PD-1)/programmed death ligand 1 (PD-L1) immunotherapy has demonstrated success in the treatment of advanced NSCLC. Recently, PD-1/PD-L1 blockade also has demonstrated interesting results in small trials of neoadjuvant treatment in stage IB to IIIA NSCLC. In addition, several clinical trials using anti–PD-1/PD-L1 immunotherapy as an adjuvant or neoadjuvant treatment in patients with resectable stage NSCLC are ongoing. However, few analyses of anti–PD-1/PD-L1 immunotherapy–related biomarkers in early-stage squamous cell lung carcinoma (SqCLC) have been reported. In this study, we evaluated PD-L1 protein expression, tumor mutation burden, and expression of an immune gene signature in early-stage SqCLC, providing data for identifying the potential role for patients with anti–PD-1/PD-L1 treatment in early-stage SqCLC.Methods
A total of 255 specimens from patients with early-stage SqCLC were identified within participating centers of the Strategic Partnering to Evaluate Cancer Signatures program. PD-L1 protein expression by immunohistochemistry was evaluated by using the Dako PD-L1 22C3 pharmDx kit on the Dako Link 48 auto-stainer (Dako, Carpinteria, CA). Tumor mutation burden (TMB) was calculated on the basis of data from targeted genome sequencing. The T-effector and interferon gamma (IFN-γ) gene signature was determined from Affymetrix gene chip data (Affymetrix, Santa Clara, CA) from frozen specimens.Results
The prevalence of PD-L1 expression was 9.8% at a tumor proportion score cutoff of at least 50%. PD-L1 mRNA and programmed cell death 1 ligand 2 mRNA positively correlated with PD-L1 protein expression on tumor cells (TCs) and tumor-infiltrating immune cells. PD-L1 protein expression on tumor-infiltrating immune cells was correlated with the T-effector and IFN-γ gene signature (p < 0.001), but not with TMB. For TCs, all of these biomarkers were independent of each other and neither PD-L1 protein expression, TMB, or T-effector and IFN-γ gene signatures were independently prognostic for patient outcomes.Conclusions
Evaluation of PD-L1 expression, TMB, and T-effector and IFN-γ gene signatures in the cohort with early-stage SqCLC found them to be independent of each other, and none was associated with overall survival. Our results also support the hypothesis that PD-L1 expression is regulated by an intrinsic mechanism on TCs and an adaptive mechanism on immune cells. 相似文献36.
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Archana S. Nimbalkar Vivek V. Shukla Ajay G. Phatak Somashekhar M. Nimbalkar 《Indian pediatrics》2013,50(4):408-410
Health status of neonates in urban slums has not been studied in smaller towns. A questionnaire was administered to 154 families of 10 urban slums of Anand (population — 197351) and 160 families from 6 villages of Anand district. The socioeconomic and education status of the slum dwellers versus rural participants were significantly lower (P<0.001). Antenatal care (79.9 vs 94.4%, P<0.001), hospital delivery (82.5 vs 93.8%, P=0.002), neonatal follow-up (27.9 vs 78.8%, P<0.001), health seeking (56.5 vs 91.3%, P<0.001), essential newborn care and exclusive breastfeeding (6.5 vs 85.6%, P<0.001) were also lower in urban slums, as compared to villages, Care seeking was low in urban slums, Hindus and illiterate mothers. Health care and socioeconomic status of neonates in slums of smaller cities is poorer than in surrounding villages. 相似文献
38.
Jason A. Zell Archana J. McEligot Argyrios Ziogas Randall F. Holcombe ∗ Hoda Anton-Culver ∗ 《Nutrition and cancer》2013,65(1):36-45
Potentially favorable effects of wine consumption on colorectal cancer (CRC) incidence have been reported, but effects on clinical outcomes are unknown. This case-only analysis was designed to investigate outcomes among familial (n = 141) and sporadic (n = 358) CRC patients enrolled in the University of California Irvine CRC gene-environment study during 1994–1996 based on their reported frequency of wine consumption in the year prior to diagnosis. Cases were categorized as either regular or infrequent wine consumers. Univariate survival rate analyses were estimated using the Kaplan and Meier method and log-rank test. Multivariate survival analyses were performed using Cox proportionalhazards ratios (HRs). Earlier stage at presentation (P = 0.034) was noted for familial (but not sporadic) CRC cases reporting regular wine consumption. An overall survival (OS) benefit was observed for familial (but not sporadic) CRC cases that were regular (10-yr OS = 75%) versus infrequent wine consumers (10-yr OS = 47%; P = 0.002). This survival improvement for familial CRC cases remained after adjustment for age, stage, treatment, and other clinically relevant factors (HR = 0.50, 95% confidence interval = 0.25–0.99). Our findings implicate favorable effects of wine consumption on stage at presentation and survival in CRC, selectively among familial CRC cases. 相似文献
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