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1.
Gregory C Gray Troy McCarthy Mark G Lebeck David P Schnurr Kevin L Russell Adriana E Kajon Marie L Landry Diane S Leland Gregory A Storch Christine C Ginocchio Christine C Robinson Gail J Demmler Michael A Saubolle Sue C Kehl Rangaraj Selvarangan Melissa B Miller James D Chappell Danielle M Zerr Deanna L Kiska Diane C Halstead Ana W Capuano Sharon F Setterquist Margaret L Chorazy Jeffrey D Dawson Dean D Erdman 《Clinical infectious diseases》2007,45(9):1120-1131
BACKGROUND: Recently, epidemiological and clinical data have revealed important changes with regard to clinical adenovirus infection, including alterations in antigenic presentation, geographical distribution, and virulence of the virus. METHODS: In an effort to better understand the epidemiology of clinical adenovirus infection in the United States, we adopted a new molecular adenovirus typing technique to study clinical adenovirus isolates collected from 22 medical facilities over a 25-month period during 2004-2006. A hexon gene sequence typing method was used to characterize 2237 clinical adenovirus-positive specimens, comparing their sequences with those of the 51 currently recognized prototype human adenovirus strains. In a blinded comparison, this method performed well and was much faster than the classic serologic typing method. RESULTS: Among civilians, the most prevalent adenovirus types were types 3 (prevalence, 34.6%), 2 (24.3%), 1 (17.7%), and 5 (5.3%). Among military trainees, the most prevalent types were types 4 (prevalence, 92.8%), 3 (2.6%), and 21 (2.4%). CONCLUSIONS: For both populations, we observed a statistically significant increasing trend of adenovirus type 21 detection over time. Among adenovirus isolates recovered from specimens from civilians, 50% were associated with hospitalization, 19.6% with a chronic disease condition, 11% with a bone marrow or solid organ transplantation, 7.4% with intensive care unit stay, and 4.2% with a cancer diagnosis. Multivariable risk factor modeling for adenovirus disease severity found that age <7 years (odds ratio [OR], 3.2; 95% confidence interval [CI], 1.4-7.4), chronic disease (OR, 3.6; 95% CI, 2.6-5.1), recent transplantation (OR, 2.7; 95% CI, 1.3-5.2), and adenovirus type 5 (OR, 2.7; 95% CI, 1.5-4.7) or type 21 infection (OR, 7.6; 95% CI, 2.6-22.3) increased the risk of severe disease. 相似文献
2.
Kannangai R Ramalingam S Vijayakumar TS Vincent AA Abraham OC Subramanian S Rupali P Mathai D Jesudason MV Sridharan G 《Indian journal of medical microbiology》2003,21(4):274-276
Currently, antiretroviral therapy has become more affordable even in developing countries and it is being used in India. Fifteen HIV-1 infected individuals, who were on highly active antiretroviral therapy (HAART), were followed up for an average period of one year. The plasma viral load and CD4+ T cell estimation done at mean intervals of 5 months and 11 months after initiation of therapy showed a good response to therapy in 14 (93%) individuals. 相似文献
3.
Classification of Breast Masses Using Selected Shape,Edge-sharpness,and Texture Features with Linear and Kernel-based Classifiers 总被引:2,自引:0,他引:2
Breast masses due to benign disease and malignant tumors related to breast cancer differ in terms of shape, edge-sharpness, and texture characteristics. In this study, we evaluate a set of 22 features including 5 shape factors, 3 edge-sharpness measures, and 14 texture features computed from 111 regions in mammograms, with 46 regions related to malignant tumors and 65 to benign masses. Feature selection is performed by a genetic algorithm based on several criteria, such as alignment of the kernel with the target function, class separability, and normalized distance. Fisher's linear discriminant analysis, the support vector machine (SVM), and our strict two-surface proximal (S2SP) classifier, as well as their corresponding kernel-based nonlinear versions, are used in the classification task with the selected features. The nonlinear classification performance of kernel Fisher's discriminant analysis, SVM, and S2SP, with the Gaussian kernel, reached 0.95 in terms of the area under the receiver operating characteristics curve. The results indicate that improvement in classification accuracy may be gained by using selected combinations of shape, edge-sharpness, and texture features. 相似文献
4.
Immunoglobulin G, A, and M Responses in Serum and Circulating Immune Complexes Elicited by the 16-Kilodalton Antigen of Mycobacterium tuberculosis 下载免费PDF全文
Alamelu Raja K. R. Uma Devi B. Ramalingam Patrick J. Brennan 《Clinical and Vaccine Immunology : CVI》2002,9(2):308-312
The 16-kDa cytosolic antigen of M. tuberculosis was purified to homogeneity by molecular sieving chromatography, and the diagnostic potential of the antigen was evaluated in various categories of patients by enzyme-linked immunosorbent assay (ELISA). The immunoglobulin G (IgG), IgA, and IgM antibody levels to 16-kDa antigen were estimated in the two polar groups, namely, smear- and culture-positive pulmonary tuberculosis (S+C+) patients and healthy subjects (HS). Sensitivities of 62, 52 and 11% with specificities of 100, 97, and 95% were obtained for the three isotypes, respectively. The total number of positives by a combination of the three isotypes was analyzed in the polar groups, and the sensitivity improved to 83% with a specificity of 93%. Even when a combination of IgG and IgA alone was considered, the sensitivity was 82% with a specificity of 97%. Polyethylene glycol precipitation of the circulating immune complex (CIC) in sera was carried out. The CIC-bound antibodies to 16-kDa antigen were assessed by ELISA in the S+C+, S−C+, and S−C− categories of patients. Measuring the IgG-IgA-IgM combination positivities of the CIC-bound antibodies gave sensitivities of 97.5, 100, and 45.3%, respectively. The specificity of the assay with these combinations was maintained at 95.4%. 相似文献
5.
Reports about the effects of ascorbate (vitamin C) on cultured cells are confusing and conflicting. Some authors show inhibition of cell death by ascorbate, whereas others demonstrate that ascorbate is cytotoxic. In this report, using three different cell types and two different culture media (Dulbecco's modified Eagle's medium and RPMI 1640), we show that the toxicity of ascorbate is due to ascorbate-mediated production of H2O2, to an extent that varies with the medium used to culture the cells. For example, 1 mM ascorbate generates 161 +/- 39 microM H2O2 in Dulbecco's modified Eagle's medium and induces apoptosis in 50% of HL60 cells, whereas in RPMI 1640 only 83 +/- 17 microM H2O2 is produced and no apoptosis is detected. Apoptosis is prevented by catalase, and direct addition of H2O2 at the above concentration to the cells has similar effects to ascorbate. These results show that ascorbate itself is not toxic to the cell lines used and that effects of ascorbate in vivo cannot be predicted from studies on cultured cells. The ability of ascorbate to interact with different cell culture media to produce H2O2 at different rates could account for many or all of the conflicting results obtained using ascorbate in cultured cell assays. 相似文献
6.
Gopalraj RK Zhu H Kelly JF Mendiondo M Pulliam JF Bennett DA Estus S 《Neurobiology of aging》2005,26(1):1-7
The low density lipoprotein receptor (LDLR) is an attractive candidate gene for genetic association with Alzheimer's disease (AD) because: (i) the LDLR is an apolipoprotein E (apoE) receptor, alleles of which have been associated with AD, (ii) LDLR resides at chromosome 19p13.3 within a region linked to AD, and (iii) LDLR modulates the homeostasis of cholesterol, which itself appears associated with AD. Therefore, we evaluated whether LDLR haplotypes alter the odds of AD by performing an association study examining three LDLR single nucleotide polymorphisms (SNPs) in 118 AD patients and 133 non-AD subjects. LDLR genotypes were obtained by TaqMan allelic discrimination assays. Although individual LDLR SNPs were not associated with AD, analyses of unambiguous haplotypes suggested the hypothesis that the 211 LDLR haplotype was associated with reduced odds of AD. We then evaluated this hypothesis in a second study cohort, i.e., the Religious Orders Study. These results supported the hypothesis that the 211 LDLR haplotype is associated with reduced odds of AD. Moreover, these data suggested further associations between LDLR variants and AD. Thus, LDLR variants appear significantly associated with AD and merit additional study. 相似文献
7.
8.
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9.
Ramalingam?Saravanan Leelavinothan?PariEmail author 《BMC complementary and alternative medicine》2005,5(1):14
Background
This study was undertaken to investigation the effect of Diasulin, a poly herbal drug composed of ethanolic extract of ten medicinal plants on blood glucose, plasma insulin, tissue lipid profile, and lipidperoxidation in alloxan induced diabetes. 相似文献10.