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Measurement of antibodies to varicella-zoster virus in a tropical population by enzyme-linked immunosorbent assay. 下载免费PDF全文
A R Venkitaraman J M Seigneurin M Baccard G M Lenoir T J John 《Journal of clinical microbiology》1984,20(3):582-583
We used the recently developed enzyme-linked immunosorbent assay for antibody to varicella-zoster virus to study the prevalence and titers of virus-specific antibody in a south Indian population of 171 individuals 0 to 25 years old. The antibody prevalence rate was less than 15% in individuals under 5 years of age and gradually rose to a maximum of 72% in young adults 15 to 25 years of age. The median age of primary infection was 12.25 years. The geometric mean antibody titers were between 1:80 and 1:160 in the age groups with antibody. These results are different from the pattern of seroepidemiology of varicella-zoster virus infection in temperate countries and indicate that varicella is predominantly a disease of young adults in the population studied. 相似文献
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Acetaminophen (APAP) hepatotoxicity is the most frequent cause of acute liver failure in the US. The mechanisms of APAP-induced liver injury have been under extensive investigations for decades, and many key events of this necrotic cell death are known today. Initially, two opposing hypotheses for cell death were proposed: reactive metabolite and protein adduct formation versus reactive oxygen and lipid peroxidation (LPO). In the end, both mechanisms were reconciled, and it is now generally accepted that the toxicity starts with formation of reactive metabolites that, after glutathione depletion, bind to cellular proteins, especially on mitochondria. This results in a mitochondrial oxidant stress, which requires amplification through a mitogen-activated protein kinase cascade, leading ultimately to enough reactive oxygen and peroxynitrite formation to trigger the mitochondrial membrane permeability transition and cell death. However, the earlier rejected LPO hypothesis seems to make a comeback recently under a different name: ferroptosis. Therefore, the objective of this review was to critically evaluate the available information about intracellular signaling mechanisms of APAP-induced cell death and those of ferroptosis. Under pathophysiologically relevant conditions, there is no evidence for quantitatively enough LPO to cause cell death, and thus APAP hepatotoxicity is not caused by ferroptosis. However, the role of mitochondria-localized minor LPO remains to be further investigated.Key words: Acetaminophen hepatotoxicity, Oncotic necrosis, Apoptosis, Ferroptosis, Lipid peroxidation, Fenton reaction, Glutathione peroxidase 4 相似文献
15.
Obesity and the risk of heart failure 总被引:1,自引:0,他引:1
Kenchaiah S Evans JC Levy D Wilson PW Benjamin EJ Larson MG Kannel WB Vasan RS 《The New England journal of medicine》2002,347(5):305-313
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Esaki Muthu Shankar Ramachandran Vignesh Kailapuri G Murugavel Pachamuthu Balakrishnan Ramalingam Sekar Charmaine AC Lloyd Suniti Solomon Nagalingeswaran Kumarasamy 《AIDS research and therapy》2007,4(1):1-7
Background
CD4+ T lymphocyte (CD4) cell count testing is the standard method for determining eligibility for antiretroviral therapy (ART), but is not widely available in sub-Saharan Africa. Total lymphocyte counts (TLCs) have not proven sufficiently accurate in identifying subjects with low CD4 counts. We developed clinical algorithms using TLCs, hemoglobin (Hb), and body mass index (BMI) to identify patients who require ART. 相似文献17.
Nigel A. Cunliffe Bimal K. Das Madhumati Ramachandran Maharaj K. Bhan Roger I. Glass Jon R. Gentsch 《Virus genes》1997,15(1):39-44
We have sequenced the genes encoding the inner capsid protein VP6 and the nonstructural proteins NSP1 and NSP4 of the Indian
neonatal serotype P8[11]G9 human/bovine reassortant candidate vaccine rotavirus strain 116E. These three genes share a high
degree of sequence and deduced amino acid homology with human prototype strain Wa. Our results confirm and extend those of
previous RNA-RNA hybridization studies which suggested that these genes are of human origin, and will facilitate examination
of the host immune response to 116E induced by natural infection and vaccination.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
18.
Umair Shabbir Momna Rubab Eric Banan-Mwine Daliri Ramachandran Chelliah Ahsan Javed Deog-Hwan Oh 《Nutrients》2021,13(1)
Polyphenols (PPs) are the naturally occurring bioactive components in fruits and vegetables, and they are the most abundant antioxidant in the human diet. Studies are suggesting that ingestion of PPs might be helpful to ameliorate metabolic syndromes that may contribute in the prevention of several chronic disorders like diabetes, obesity, hypertension, and colon cancer. PPs have structural diversity which impacts their bioavailability as they accumulate in the large intestine and are extensively metabolized through gut microbiota (GM). Intestinal microbiota transforms PPs into their metabolites to make them bioactive. Interestingly, not only GM act on PPs to metabolize them but PPs also modulate the composition of GM. Thus, change in GM from pathogenic to beneficial ones may be helpful to ameliorate gut health and associated diseases. However, to overcome the low bioavailability of PPs, various approaches have been developed to improve their solubility and transportation through the gut. In this review, we present evidence supporting the structural changes that occur after metabolic reactions in PPs (curcumin, quercetin, and catechins) and their effect on GM composition that leads to improving overall gut health and helping to ameliorate metabolic disorders. 相似文献
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L. Zucco P. Santer N. Levy M. Hammer S. D. Grabitz S. Nabel S. K. Ramachandran 《Anaesthesia》2021,76(1):36-44
Sevoflurane and desflurane are the most commonly used volatile anaesthetics for maintenance of anaesthesia. In this study, we aimed to evaluate the relationship between choice of volatile anaesthetic and early postoperative respiratory complications, and to address a critical knowledge gap in safety outcomes between these two commonly used agents. We performed a retrospective analysis of adult (non-cardiac surgery) patients who received sevoflurane or desflurane for the maintenance of general anaesthesia at our institution between 2005 and 2018. We evaluated the association between desflurane exposure (when compared with sevoflurane) and the primary outcome of postoperative respiratory complications, defined by early post-extubation desaturation (SpO2 < 90%) or re-intubation within 7 days postoperatively. Multivariable regression analyses were performed and adjusted for confounding factors, including patient, anaesthetic and surgical factors. Propensity matched, interaction and sub-group analyses were performed to assess outcomes in high-risk groups: morbidly obese (BMI > 35 kg.m−2); elderly (age > 65 years); and high risk of respiratory complications as well as the primary outcome at 24 h. Desflurane was used for 23,830 patients and sevoflurane for 84,608 patients. Patients exposed to desflurane did not demonstrate a reduced risk of postoperative respiratory complications when compared with sevoflurane (adjusted odds ratio 0.99, 95%CI 0.94–1.04, p = 0.598). These findings were consistent across all sub-groups of high-risk patients and in the propensity score matched cohort. In summary, desflurane use was not associated with reduced postoperative respiratory complications when compared with sevoflurane. In the context of environmental and cost concerns with volatile anaesthetic agents, our study provides important data to support organisational decisions regarding the use of desflurane. 相似文献