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91.
Eric G. Leach Latha Narayanan Pamela A. Havre Edward J. Gunther Toni M. Yeasky Peter M. Glazer 《Environmental and molecular mutagenesis》1996,28(4):459-464
Transgenic mice carrying multiple copies of a recoverable λ phage shuttle vector carrying the supF mutation reporter gene (λsupF) were constructed for the purpose of studying mutagenesis in a whole animal. Spontaneous mutations in rescued supF target genes from mouse liver and skin were analyzed. The mutation frequency was similar in both tissues (in the range of 2 × 10−5), but the spectrum of point mutations was distinct, with transitions common in the skin and transversions more prominent in the liver (P = 0.01). These results may help to elucidate pathways of endogenous mutagenesis in vivo, and they illustrate potentially important tissue-specific differences in genetic instability. © 1996 Wiley-Liss, Inc. 相似文献
92.
Sameera Nayak Taraprasad Das Deepika Parameswarappa Savitri Sharma Saumya Jakati Subhadra Jalali Raja Narayanan Soumyava Basu Mudit Tyagi Vivek Pravin Dave Rajeev Reddy Pappuru Avinash Pathengay Hrishikesh Kaza Padmaja Kumari Rani Shashwat Behera Niroj Kumar Sahoo Aditya Kapoor Hitesh Agrawal Komal Agarwal Brijesh Takkar Vishal Ramesh Raval 《Indian journal of ophthalmology》2021,69(12):3664
Purpose:Intraocular infection in patients with COVID-19 could be different in the presence of treatment with systemic corticosteroid and immunosuppressive agents. We describe the epidemiology and microbiological profile of intraocular infection in COVID-19 patients after their release from the hospital.Methods:We analyzed the clinical and microbiological data of laboratory-confirmed COVID-19 patients from April 2020 to January 2021 presenting with features of endogenous endophthalmitis within 12 weeks of their discharge from the hospital in two neighboring states in South India. The data included demography, systemic comorbidities, COVID-19 treatment details, time interval to visual symptoms, the microbiology of systemic and ocular findings, ophthalmic management, and outcomes.Results:The mean age of 24 patients (33 eyes) was 53.6 ± 13.5 (range: 5–72) years; 17 (70.83%) patients were male. Twenty-two (91.6%) patients had systemic comorbidities, and the median period of hospitalization for COVID-19 treatment was 14.5 ± 0.7 (range: 7–63) days. Infection was bilateral in nine patients. COVID-19 treatment included broad-spectrum systemic antibiotics (all), antiviral drugs (22, 91.66% of patients), systemic corticosteroid (21, 87.5% of patients), supplemental oxygen (18, 75% of patients), low molecular weight heparin (17, 70.8% of patients), admission in intensive care units (16, 66.6% of patients), and interleukin-6 inhibitor (tocilizumab) (14, 58.3% of patients). Five (20.8%) patients died of COVID-19-related complications during treatment for endophthalmitis; one eye progressed to pan ophthalmitis and orbital cellulitis; eight eyes regained vision >20/400. Fourteen of 19 (73.7%) vitreous biopsies were microbiologically positive (culture, PCR, and microscopy), and the majority (11 patients, 78.5%) were fungi.Conclusion:Intraocular infection in COVID-19 patients is predominantly caused by fungi. We suggest a routine eye examination be included as a standard of care of COVID-19. 相似文献
93.
PN Rao Abraham Koshy Jacob Philip Narayanan Premaletha Joy Varghese Krishnasamy Narayanasamy Samir Mohindra Nitin Vikas Pai Manoj Kumar Agarwal Ashokna Konar Hasmukh B Vora 《World journal of hepatology》2014,6(7):520-526
AIM: To study the safety and efficacy of pegylated interferon alfa-2b, indigenously developed in India, plus ribavirin in treatment of hepatitis C virus(HCV). METHODS: One-hundred HCV patients were enrolled in an open-label, multicenter trial. Patients were treated with pegylated interferon alfa-2b 1.5 μg/kg per week subcutaneously plus oral ribavirin 800 mg/d for patients with genotypes 2 and 3 for 24 wk. The same dose of peginterferon plus weight-based ribavirin(800 mg/d for ≤ 65 kg; 1000 mg/d for 65-85 kg; 1200 mg/d for 85-105 kg; 1400 mg/d for 105 kg body weight) was administered for 48 wk for patients with genotypes 1 and 4. Serological and biochemical responses of patients were assessed.RESULTS: Eighty-two patients(35 in genotypes 1 and 4 and 47 in 2 and 3), completed the study. In genotype 1, 25.9% of patients achieved rapid virologic response(RVR): while the figures were 74.1% for early virologic response(EVR) and 44.4% for sustained virologic response(SVR). For genotypes 2 and 3, all patients bar one belonged to genotype 3, and of those, 71.4%, 87.5%, and 64.3% achieved RVR, EVR, and SVR, respectively. In genotype 4, 58.8%, 88.2%, and 52.9% of patients achieved RVR, EVR, and SVR, respectively. The majority of patients attained normal levels of alanine aminotransferase by 4-12 wk of therapy. Most patients showed a good tolerance for the treatment, although mild-to-moderate adverse events were exhibited; only two patients discontinued the study medication due to serious adverse events(SAEs). Eleven SAEs were observed in nine patients; however, only four SAEs were related to study medication.CONCLUSION: Peginterferon alfa-2b, which was developed in India, in combination with ribavirin, is a safe and effective drug in the treatment of HCV. 相似文献
94.
N Narayanan 《Mechanisms of ageing and development》1987,38(2):127-143
Age-associated decline in the Ca2+ pump function of cardiac sarcoplasmic reticulum (SR), and increase in the Ca2+ pump activity of sarcolemma (SL) were suggested by my previous study which compared the ATP-energized in vitro Ca2+ transport activities of these membranes from young (3-4-month-old) and aged (24-25-month-old) rat myocardium (Biochim. Biophys. Acta, 678 (1981) 442-459). In the present study, ATP-dependent Ca2+ transport and Ca2+ sensitive ATPase activities of SR and SL derived from the myocardium of rats aged 3 (young), 6 (young adult), 12 (adult), 18 (aging) and 24 (aged) months were determined so as to further characterize age-related changes in the Ca2+ transport function of these membranes. The rates of ATP-dependent Ca2+ accumulation by SR from 3- and 6-month-old rats were virtually similar whereas the rates of Ca2+ accumulation by this membrane from 12-, 18- and 24-month-old rats were significantly lower when compared to 3- or 6-month-old rats; the magnitude of this age-related decline amounted to approx. 18, 45 and 50%, respectively, for SR from 12-, 18- and 24-month-old animals. In contrast to the above findings with SR, SL from 18- and 24-month-old rats displayed substantially higher rates (approx. 45 and 80% increase, respectively, at 18 and 24 months of age) of ATP-dependent Ca2+ accumulation than SL preparations from 3-, 6- and 12-month-old rats; no significant age-related difference was evident between the latter three age groups. The divergent age-related changes in the Ca2+ accumulating activities of SR and SL were seen at varying Ca2+ concentrations (0.54-25.2 microM). With either membrane, kinetic analysis showed that the velocity of Ca2+ transport, but not the apparent affinity of the transport system for Ca2+ underwent age-related changes. The Ca2+-stimulated ATPase activities of SR and SL were not altered significantly with increasing age from 3 to 24 months. Comparison of the 'combined Ca2+ transport activity' of SR and SL from rats of various ages showed a significant overall age-related decline in the rates of Ca2+ transport via the ATP-driven membrane Ca2+ pumps; this decrement in membrane function was moderate at 12 months of age (approx. 16%) and became pronounced with advancing age thereafter (approx. 35 and 38%, respectively, at 18 and 24 months of age). Similar progressive age-related decline was observed in the ATP-dependent Ca2+ sequestering activity of cardiac homogenates.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
95.
Daniel Ian McSkimming Shima Dastgheib Eric Talevich Anish Narayanan Samiksha Katiyar Susan S. Taylor Krys Kochut Natarajan Kannan 《Human mutation》2015,36(2):175-186
Protein kinases represent a large and diverse family of evolutionarily related proteins that are abnormally regulated in human cancers. Although genome sequencing studies have revealed thousands of variants in protein kinases, translating “big” genomic data into biological knowledge remains a challenge. Here, we describe an ontological framework for integrating and conceptualizing diverse forms of information related to kinase activation and regulatory mechanisms in a machine readable, human understandable form. We demonstrate the utility of this framework in analyzing the cancer kinome, and in generating testable hypotheses for experimental studies. Through the iterative process of aggregate ontology querying, hypothesis generation and experimental validation, we identify a novel mutational hotspot in the αC‐β4 loop of the kinase domain and demonstrate the functional impact of the identified variants in epidermal growth factor receptor (EGFR) constitutive activity and inhibitor sensitivity. We provide a unified resource for the kinase and cancer community, ProKinO, housed at http://vulcan.cs.uga.edu/prokino . 相似文献
96.
Joseph L. McDevitt Ali Alian Baljendra Kapoor Stacy Bennett Amanjit Gill Abraham Levitin Mark Sands K.V. Narayanan Menon Federico N. Aucejo Bassam Estfan Anil K. Pillai Sanjeeva P. Kalva Gordon McLennan 《Journal of vascular and interventional radiology : JVIR》2017,28(10):1371-1377
Purpose
To compare overall survival and toxicities after yttrium-90 (90Y) radioembolization and chemoembolization with drug-eluting embolics (DEE) in patients with infiltrative hepatocellular carcinoma (HCC).Materials and Methods
Retrospective review of 50 patients with infiltrative HCC without main portal vein invasion who were treated with 90Y radioembolization (n = 26) or DEE chemoembolization (n = 24) between March 2007 and August 2012 was completed. Infiltrative tumors were defined by cross-sectional imaging as masses that lacked well-demarcated boundaries, and treatment allocations were made by a multidisciplinary tumor board. Median age was 63 years; median tumor diameter was 9.0 cm; and there were no significant differences between groups in performance status, severity of liver disease, or HCC stage. Toxicities were graded by Common Terminology Criteria for Adverse Events v4.03. Overall survival from treatment was assessed by Kaplan-Meier analysis, with analysis of potential predictors of survival with log-rank test.Results
There was no difference in the average number of procedures performed in each treatment group (DEE, 1.5 ± 1.1; 90Y, 1.6 ± 0.5; P = .97), and technical success was achieved in all cases. Abdominal pain (73% vs 33%; P = .004) and fever (38% vs 8%; P = .01) were more frequent after DEE chemoembolization. There was no significant difference in median overall survival between treatment groups after treatment (DEE, 9.9 months; 90Y, 8.1 months; P = .11).Conclusions
90Y radioembolization and DEE chemoembolization provided similar overall survival in the treatment of infiltrative HCC without main portal vein invasion. Abdominal pain and fever were more frequent after DEE chemoembolization. 相似文献97.
Prakash K Varma D Rajan M Kamlesh NP Zacharias P Ganesh Narayanan R Philip M 《The Indian journal of surgery》2010,72(4):318-322
Laparoscopic approach for treatment of colorectal malignancy is gaining acceptance gradually; however the benefits of laparoscopic
surgery in colonic and rectal tumours is still open to debate. This study aims at a retrospective analysis of operative and
short term outcome of patients with rectosigmoid tumours. A retrospective analysis of operative, postoperative and short-term
outcome of 62 patients who underwent laparoscopic colorectal resection for cancer of rectosigmoid region were compared with
a same number of parameters-matched patients who underwent open colorectal resection. Blood transfusion requirement was significantly
more in the open group compared to the laparoscopy group (38.7% versus 6.4%, p = 0.001). ICU stay was less in the laparoscopy
group (p = <0.05) and they were started on oral liquid diet earlier (p = 0.013). The number of the lymph nodes retrieved,
positive distal margin and radial involvement were similar in both groups. The hospital stay was significantly shorter in
laparoscopy group (8.4 versus 13.8 days, p < 0.05). Radical operation for rectosigmoid tumors is technically feasible with
laparoscopic surgery. Laparoscopic approach is associated with less blood loss, transfusion and significantly less ICU stay.
Laparoscopic group recovers early and needs less hospital stay 相似文献
98.
Gastric carcinoma following surgery for benign peptic ulcer disease is being increasingly reported. The authors have reviewed their experience at Saint Francis Hospital and Medical Center and Mount Sinai Hospital from 1970 to 1980 and found 319 cases of gastric carcinoma, 16 of whom had undergone previous surgical procedures for peptic ulcer disease, with an incidence of 5 per cent of gastric stump carcinoma. The average time interval for the development of gastric stump carcinoma was 17.4 years, ranging from 5 to 49 years. The average survival after the diagnosis was 4.6 months, making the prognosis uniformly poor, probably due to delayed diagnosis. Treatment modalities consisted of major and minor surgical procedures, medical therapy, and no treatment in some instances. It is recommended that all patients who undergo operations for peptic ulcers have careful long-term follow-up. Vague gastrointestinal symptoms occurring in these patients, especially 10 years or more after surgery, require endoscopy and biopsies of the gastric stump to exclude gastric stump carcinoma. 相似文献
99.
Effect of gamma-interferon on collagen synthesis by normal and fibrotic human lung fibroblasts. 总被引:4,自引:0,他引:4
Increased lung collagen and increased collagen synthesis by lung fibroblasts is well recognized in pulmonary fibrosis. gamma-Interferon has been shown to inhibit collagen synthesis by fibroblasts. To understand its effect on lung fibroblasts we compared how this lymphokine affects the growth and collagen synthesis of normal and fibrotic human lung fibroblasts. The results showed that gamma-IFN inhibited DNA synthesis in all fibroblast strains examined. Both collagen production and type 1 mRNA levels were reduced in three normal and two fibrotic cell strains exposed to gamma-IFN, while they were not affected in one strain from fibrotic lung. Even though an occasional cell was unaffected by the gamma-IFN, collagen mRNA level was reduced in most cells and it remained reduced for 48 h after removing the gamma-IFN. These results show that gamma-IFN inhibits the growth of fibroblast cultures derived from normal and fibrotic human lungs and suppresses collagen synthesis in most of these cells. 相似文献
100.
Sujata Narayanan Neeraj Agarwal Kristina Callis-Duffin Julia Batten 《The American journal of the medical sciences》2010,339(6):580-581
Sunitinib is an oral tyrosine kinase inhibitor, which is indicated for the treatment of renal cell carcinoma and gastrointestinal stromal tumors. The authors report the case of a patient who underwent treatment for renal cell carcinoma and noted additional benefit by improvement in his psoriatic skin lesions. This may be attributed to the antiangiogenic activity of sunitinib by inhibition of vascular endothelial growth factor receptors. 相似文献