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91.
Adel Zaki M.D. Dr. P.H. Nachimuthu Natarajan M.S. Curtis J. Mettlin Ph.D. 《Cancer》1993,72(2):602-606
Background. The independent effect of race on response to treatment and prognosis in Hodgkin disease is unclear. Methods. The study included 9482 patients with histologically confirmed Hodgkin disease reported by 1084 different hospitals and institutions in the United States. The independent effect of race on response to treatment and recurrence was estimated using the logistic model. Cox proportional hazard model was applied to determine the independent effect of race and other covariables on risk of death. Results. Complete remission occurred in more white patients (67.3%) than black patients (58.2%). Recurrences were reported more often in black patients than in white patients (40.3% and 30.9% respectively). Controlling for confounding variables, race has a significant independent effect on remission and recurrence (P < 0.05). In the first 5 years after diagnosis of Hodgkin disease, the patient age at diagnosis, clinical stage, and histologic type were significant predictors for the risk of death. At 5–10 years after a diagnosis of Hodgkin disease, age, clinical stage, and race of the patient were found to be significant risk factors (whites versus blacks: RR = 0.56; P < 0.05). Conclusions. Race is a significant predictor for remission, recurrence and survival in Hodgkin disease. Black patients have a more unfavorable prognosis than do white patients. 相似文献
92.
A series of 2,4-aryl-4-((arylsulfonyl)methyl)-4H-benzo[d][1,3]oxazines in good to excellent yields have directly been obtained from N-(2-vinylphenyl)amides and thiols by employing a mixture of K2S2O8-activated charcoal in aqueous acetonitrile solution at 50 °C. A plausible mechanism for the reaction is reported. It reveals that the reaction follows a radical pathway and the persulfate has been the oxygen source for formation of the sulfone group in the products. It is worth mentioning that this protocol utilizes an easily accessible K2S2O8-activated charcoal mixture and thiols, respectively, as an oxidant and sulfonylating precursors for the first time.A simple method for the synthesis of 2,4-aryl-4-((arylsulfonyl)methyl)-4H-benzo[d][1,3]oxazines using an easily accessible K2S2O8-activated charcoal mixture and thiols, respectively, as an oxidant and sulfonylating precursors has been described. 相似文献
93.
Natarajan Sisubalan Chandrasekaran Karthikeyan Venugopal Senthil Kumar Kokkarachedu Varaprasad Abdulrahman Syed ahamed Haja Hameed Ramar Vanajothi Rotimi Sadiku 《RSC advances》2021,11(49):30623
Mishandling of antibiotics often leads to the development of multiple drug resistance (MDR) among microbes, resulting in the failure of infection treatments and putting human health at great risk. As a response, unique nanomaterials with superior bioactivity must be developed to combat bacterial infections. Herein, CeO2-based nanomaterials (NMs) were synthesized by employing cerium(iii) nitrate and selective alkaline ions. Moreover, the influence of alkaline ions on CeO2 was investigated, and their characteristics, viz.: biochemical, structural, and optical properties, were altered. The size of nano Ba-doped CeO2 (BCO) was ∼2.3 nm, relatively smaller than other NMs and the antibacterial potential of CeO2, Mg-doped CeO2 (MCO), Ca-doped CeO2 (CCO), Sr-doped CeO2 (SCO), and Ba-doped CeO2 (BCO) NMs against Streptococcus mutans (S. mutans) and Staphylococcus aureus (S. aureus) strains was assessed. BCO outperformed all NMs in terms of antibacterial efficacy. In addition, achieving the enhanced bioactivity of BCO due to reduced particle size facilitated the easy penetration into the bacterial membrane and the presence of a sizeable interfacial surface. In this study, the minimum quantity of BCO required to achieve the complete inhibition of bacteria was determined to be 1000 μg mL−1 and 1500 μg mL−1 for S. mutans and S. aureus, respectively. The cytotoxicity test with L929 fibroblast cells demonstrated that BCO was less toxic to healthy cells. Furthermore, BCO did not show any toxicity and cell morphological changes in the L929 fibroblast cells, which is similar to the control cell morphology. Overall, the results suggest that nano BCO can be used in biomedical applications, which can potentially help improve human health conditions.The highest antibacterial activity was achieved for Ba-doped CeO2 (BCO) NMs and is suitable for healthcare applications. 相似文献
94.
95.
Jon-David R. Schwalm Harindra C. Wijeysundera Jack V. Tu Helen Guo Kori J. Kingsbury Madhu K. Natarajan 《The Canadian journal of cardiology》2014
Background
The Variation in Revascularization Practice in Ontario (VRPO) project helped describe variations in revascularization across Ontario. Coronary anatomy was the most important predictor of revascularization strategy. We conducted a novel angiographic substudy of the VRPO cohort to: (1) validate “real-world” coronary angiographic reporting in the province of Ontario; and (2) understand the relationship between variability in revascularization and coronary anatomy complexity.Methods
Seventeen hundred eighty-seven angiograms from 17 cardiac centres were randomly sampled from the VRPO cohort. The core lab assessment involved blinded interpretation of each angiographic film. A comparison of agreement in coronary anatomy and treatment strategy between abstracted chart data from the VRPO study and blinded film review was undertaken. Synergy Between Percutaneous Coronary Intervention With Taxus and Cardiac Surgery (SYNTAX) scores were calculated for all patients with multivessel disease.Results
The weighted κ statistic for coronary anatomy was 0.75 (95% confidence interval, 0.72-0.77), suggesting substantial agreement between abstracted chart data and blinded film review. The weighted κ for revascularization strategy was 0.51 (95% confidence interval, 0.47-0.54) suggesting only moderate agreement. There were no significant differences in the mean/median SYNTAX scores across all 4 percutaneous coronary intervention: coronary artery bypass graft (CABG) groups.Conclusions
Abstracted chart data in the VRPO project provides a valid assessment of coronary anatomy and furthermore serves as validation of “real-world” coronary angiographic reporting in the province of Ontario. The uniform distribution of coronary complexity across centres in Ontario, with respect to the SYNTAX score, suggests the variation of percutaneous coronary intervention: CABG ratio is not related to a difference in coronary anatomy complexity across sites, but rather a difference in management strategies for the same anatomy. 相似文献96.
97.
In the present study, an attempt was made to study the feasibility of nanoparticulate adsorbents in the presence of an absorption enhancer, as a drug delivery tool for the administration of erythropoietin (EPO) to the small intestine. Liquid filled nano- and micro-particles (LFNPS/LFMPS) were prepared using solid adsorbents such as porous silicon dioxide (Sylysia 550), carbon nanotubes (CNTs), carbon nanohorns, fullerene, charcoal and bamboo charcoal. Surfactants such as a saturated polyglycolysed C8-C18 glyceride (Gelucire 44/14), PEG-8 capryl/caprylic acid glycerides (Labrasol) and polyoxyethylene hydrogenated castor oil derivative (HCO-60) were used as an absorption enhancer at 50mg/kg along with casein/lactoferrin as enzyme inhibitors. The absorption of EPO was studied by measuring serum EPO levels by an ELISA method after small intestinal administration of EPO-LFNPS preparation to rats at the EPO dose level of 100 IU/kg. Among the adsorbents studied, CNTs showed the highest serum EPO level of 62.7 +/- 11.6 mIU/ml. In addition, with the use of casein, EPO absorption was improved, C(max) 143.1 +/- 15.2 mIU/ml. Labrasol showed the highest absorption enhancing effect after intra-jejunum administration than Gelucire 44/14 and HCO-60, 25.6 +/- 3.2 and 22.2 +/- 3.6 mIU/ml, respectively. Jejunum was found to be the best absorption site for the absorption of EPO from LFNPS. The use of CNTs as LFNPS, improved the bioavailability of EPO to 11.5% following intra-small intestinal administration. 相似文献
98.
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
99.
Incisional hernia remains a very common postoperative complication. These are encountered with an incidence of up to 20 % following laparotomy. These hernias enlarge over time, making the repair difficult, and serious complications like bowel obstruction, strangulation and enterocutaneous fistula can occur. Hence, elective repair is indicated to avoid these complications. Implantation of a prosthetic mesh is nowadays considered as the standard treatment due to low hernia recurrence. The most common mesh repair techniques used are the onlay repair, sublay repair and laparoscopic intraperitoneal onlay mesh (IPOM). However, it is still not clear which technique among the three is superior. A study consisting of 30 patients who underwent incisional hernia repair by onlay, laparoscopic and preperitoneal mesh repair with abdominoplasty was conducted in the Coimbatore Medical College and Hospital. Of the three groups, the preperitoneal repair with abdominoplasty was found to have better patient compliance and satisfaction with regard to occurrence of complications and appearance of the abdominal wall without laxity in a single sitting. 相似文献
100.
C. Kreatsoulas M. K Natarajan R. Khatun J. L Velianou S. S Anand 《Journal of internal medicine》2010,268(1):66-74
Abstract. Kreatsoulas C, Natarajan MK, Khatun R, Velianou JL, Anand SS (McMaster University; CARING Network, McMaster University; Population Health Research Institute, McMaster University and Hamilton Health Sciences; Interventional Cardiology, Hamilton Health Sciences; Eli Lilly Canada–May Cohen Chair in Women's Health, McMaster University; Michael G. DeGroote‐Heart and Stroke Foundation of Ontario Chair in Population Health Research, McMaster University; Population Genomics Program, McMaster University; McMaster University, Hamilton, ON, Canada). Identifying women with severe angiographic coronary disease. J Intern Med 2010; 268 :66–74. Objectives. To determine sex/gender differences in the distribution of risk factors according to age and identify factors associated with the presence of severe coronary artery disease (CAD). Design. We analysed 23 771 consecutive patients referred for coronary angiography from 2000 to 2006. Subjects. Patients did not have previously diagnosed CAD and were referred for first diagnostic angiography. Outcome measures. Patients were classified according to angiographic disease severity. Severe CAD was defined as left main stenosis ≥50%, three‐vessel disease with ≥70% stenosis or two‐vessel disease including proximal left anterior descending stenosis of ≥70%. Univariate and multivariate logistic regression was used to assess the association between risk factors and angina symptoms with severe CAD. Results. Women were less likely to have severe CAD (22.3% vs. 36.5%) compared with men. Women were also significantly older (69.8 ± 10.6 vs. 66.3 ± 10.7 years), had higher rates of diabetes (35.0% vs. 26.6%), hypertension (74.8% vs. 63.3%) and Canadian Cardiovascular Society (CCS) class IV angina symptoms (56.7% vs. 47.8%). Men were more likely to be smokers (56.9% vs. 37.9%). Factors independently associated with severe CAD included age (OR = 1.05; 95% CI 1.05–1.05, P < 0.01), male sex (OR = 2.43; CI 2.26–2.62, P < 0.01), diabetes (OR = 2.00; CI 1.86–2.18, P < 0.01), hyperlipidaemia (OR = 1.50; CI 1.39–1.61, P < 0.01), smoking (OR = 1.10; CI 1.03–1.18, P = 0.06) and CCS class IV symptoms (OR = 1.43; CI 1.34–1.53, P < 0.01). CCS Class IV angina was a stronger predictor of severe CAD amongst women compared with men (women OR = 1.82; CI 1.61–2.04 vs. men OR = 1.28; CI 1.18–1.39, P < 0.01). Conclusions. Women referred for first diagnostic angiography have lower rates of severe CAD compared with men across all ages. Whilst conventional risk factors, age, sex, diabetes, smoking and hyperlipidaemia are primary determinants of CAD amongst women and men, CCS Class IV angina is more likely to be associated with severe CAD in women than men. 相似文献