University of Texas Medical Branch

About: University of Texas Medical Branch is a education organization based out in Galveston, Texas, United States. It is known for research contribution in the topics: Population & Virus. The organization has 22033 authors who have published 38268 publications receiving 1517502 citations. The organization is also known as: The University of Texas Medical Branch at Galveston & UTMB.

Physical and Functional Interactions of Human DNA Polymerase η with PCNA

Abstract: Human DNA polymerase η (hPolη) functions in the error-free replication of UV-damaged DNA, and mutations in hPolη cause cancer-prone syndrome, the variant form of xeroderma pigmentosum. However, in spite of its key role in promoting replication through a variety of distorting DNA lesions, the manner by which hPolη is targeted to the replication machinery stalled at a lesion site remains unknown. Here, we provide evidence for the physical interaction of hPolη with proliferating cell nuclear antigen (PCNA) and show that mutations in the PCNA binding motif of hPolη inactivate this interaction. PCNA, together with replication factor C and replication protein A, stimulates the DNA synthetic activity of hPolη, and steady-state kinetic studies indicate that this stimulation accrues from an increase in the efficiency of nucleotide insertion resulting from a reduction in the apparent Km for the incoming nucleotide.

Comparison of Four-Drug Regimens and Pairs of Sequential Three-Drug Regimens as Initial Therapy for HIV-1 Infection

Abstract: BACKGROUND It is unclear whether therapy for human immunodeficiency virus type 1 (HIV-1) should be initiated with a four-drug or two sequential three-drug regimens. METHODS In this multicenter trial we compared initial therapy involving four-drug regimens containing efavirenz and nelfinavir in combination with either didanosine and stavudine or zidovudine and lamivudine with therapy involving two consecutive three-drug regimens the first of which contained either efavirenz or nelfinavir. RESULTS A total of 980 subjects were followed for a median of 2.3 years. There was no significant difference in the occurrence of regimen failures between the group that received the four-drug regimen containing didanosine, stavudine, nelfinavir, and efavirenz and the groups that received the three-drug regimens beginning with didanosine, stavudine, and nelfinavir (hazard ratio for regimen failure, 1.24) or didanosine, stavudine, and efavirenz (hazard ratio, 1.01). There was no significant difference between the group that received the four-drug regimen containing zidovudine, lamivudine, nelfinavir, and efavirenz and the groups that received the three-drug regimens beginning with zidovudine, lamivudine, and nelfinavir (hazard ratio, 1.06) or zidovudine, lamivudine, and efavirenz (hazard ratio, 1.45). A four-drug regimen was associated with a longer time to the first regimen failure than the three-drug regimens containing didanosine, stavudine, and nelfinavir (hazard ratio for a first regimen failure, 0.55); didanosine, stavudine, and efavirenz (hazard ratio, 0.63); or zidovudine, lamivudine, and nelfinavir (hazard ratio, 0.49), but not the three-drug regimen containing zidovudine, lamivudine, and efavirenz (hazard ratio, 1.21). CONCLUSIONS There was no significant difference in the duration of successful HIV-1 treatment between a single four-drug regimen and two consecutive three-drug regimens. Among these treatment strategies, initiating therapy with the three-drug regimen of zidovudine, lamivudine, and efavirenz is the optimal choice.

Multicenter evaluation of proposed standardized procedure for antifungal susceptibility testing of filamentous fungi.

Abstract: A multicenter study was conducted to expand the generation and analysis of data that supports the proposal of a reference method for the antifungal susceptibility testing of filamentous fungi. Broth microdilution MICs of amphotericin B and itraconazole were determined in 11 centers against 30 coded duplicate pairs of Aspergillus spp., Fusarium spp., Pseudallescheria boydii, and Rhizopus arrhizus. The effect of inoculum density (approximately 10(3) and 10(4) CFU/ml), incubation time (24, 48, and 72 h), and procedure of MIC determination (conventional and colorimetric [Alamar Blue] evaluation of growth inhibition) on intra- and interlaboratory agreement was analyzed. Based on intra- (97 to 100%) and interlaboratory (94 to 95%) agreement for both drugs, the overall optimal testing conditions identified were determination of colorimetric MICs after 48 to 72 h of incubation with an inoculum density of approximately 10(4) CFU/ml. These testing conditions are proposed as guidelines for a reference broth microdilution method.

The NIMH methods for the epidemiology of child and adolescent mental disorders (MECA) study: Background and methodology

Abstract: Objective A collaborative study was conducted to develop methods for surveys of mental disorder and service utilization in unscreened population-based samples of children and adolescents. Method Probability household samples of youths 9 through 17 years of age were selected at four sites and interviews were conducted with a total of 1,285 pairs of youths and their adult caretakers in their homes. Lay interviewers administered a computer-assisted version of the NIMH Diagnostic Interview Schedule for Children Version 2.3 and structured interviews to assess demographic variables, functional impairment, risk factors, service utilization, and barriers to service utilization. Results More than 7,500 households were enumerated at four sites, with enumeration response rates above 99%. Across sites, 84% of eligible youth–caretaker pairs were interviewed for about 2 hours each. Ninety-five percent of both youths and caretakers found the interview to be acceptable enough to recommend to a friend. Conclusions These findings indicate that large-scale epidemiological surveys of mental disorders and mental health service use involving lengthy interviews in the homes of unscreened population-based samples of youths and their adult caretakers are acceptable to the community and can achieve good response rates. The other reports in this Special Section address the reliability and validity of the various survey instruments and other key findings.