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1.
ABSTRACT

HIV-positive men who have sex with men (HIV+MSM) in India need culturally-relevant interventions to promote safer sex. We tested a multi-level intervention among HIV+MSM that targeted individual, interpersonal, and community factors, based on the Social-Personal and Social Ecological Models. We conducted a 2?×?2 factorial RCT with 119 HIV+MSM randomised to receive either an individual-level intervention (ILI) using motivational interviewing to promote safer sex, a community-level intervention (CLI) to strengthen community norms toward safer sex and reduce stigma among MSM communities, a multi-level intervention combining the individual- and community-level interventions (ILI?+?CLI), or standard-of-care control. Participants completed pre- and post-intervention assessments of a composite sexual risk score and a process evaluation to assess fidelity and satisfaction. Out of the 119 HIV+MSM, 106 (89.0%) completed pre- and post-intervention assessments. Generalised Estimating Equation models showed that both CLI (Incidence Rate Ratio [IRR]?=?.67, 95% CI .47 to .96) and ILI?+?CLI (IRR?=?.66, 95% CI .48 to .91) groups had a statistically significant decrease in sexual risk compared to the standard-of-care. The interventions had high levels of fidelity and satisfaction. This pilot RCT demonstrated feasibility and potential effectiveness of a multi-level intervention that addresses individual, interpersonal and community-level contributors of sexual risk among HIV+MSM.  相似文献   
2.
It is difficult to distinguish between carcinoid tumors of the pancreatic head and periampullary region and carcinomas preoperatively. Between 1996 and 2002, 125 consecutive pancreaticoduodenectomies done by us for periampullary tumors (14 carcinoids, 111 carcinomas) were analyzed. Patients with carcinoid tumors had significantly younger mean age (48 vs. 54 years), longer history (32 vs. 8 weeks), lower serum total bilirubin levels (1.4 vs. 6.3 mg/dL) and on CT scan, had larger, well-localized tumors (5 cm vs. 2 cm). Their postoperative course was better with no mortality or major morbidity, whereas after resection for carcinoma 7 (6.3%) patients died and 30 (27%) had major postoperative complications. Thus, a tumor of this region in a young patient with indolent history, low bilirubin level and with CT scan depicting a large expansile lesion suggests a carcinoid. Such tumors may be safely resected with low postoperative morbidity and mortality and good long-term prognosis.  相似文献   
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The yeast two-hybrid system and far-Western protein blot analysis were used to demonstrate dimerization of human double-stranded RNA (dsRNA)-dependent protein kinase (PKR) in vivo and in vitro. A catalytically inactive mutant of PKR with a single amino acid substitution (K296R) was found to dimerize in vivo, and a mutant with a deletion of the catalytic domain of PKR retained the ability to dimerize. In contrast, deletion of the two dsRNA-binding motifs in the N-terminal regulatory domain of PKR abolished dimerization. In vitro dimerization of the dsRNA-binding domain required the presence of dsRNA. These results suggest that the binding of dsRNA by PKR is necessary for dimerization. The mammalian dsRNA-binding protein TRBP, originally identified on the basis of its ability to bind the transactivation region (TAR) of human immunodeficiency virus RNA, also dimerized with itself and with PKR in the yeast assay. Taken together, these results suggest that complexes consisting of different combinations of dsRNA-binding proteins may exist in vivo. Such complexes could mediate differential effects on gene expression and control of cell growth.  相似文献   
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Pulmonary function in healthy young adult Indians in Madras.   总被引:2,自引:0,他引:2       下载免费PDF全文
Forced vital capacity, forced expiratory volume in one second, functional residual capacity, residual volume, total lung capacity, and single breath diffusing capacity measurements (effective alveolar volume, carbon monoxide transfer factor, and transfer coefficient) were measured in 247 young healthy adults (130 male, 117 female) aged 15-40 years living in Madras. Subjects were of Dravidian stock, living at sea level with rice as their staple diet. Regression equations were derived for men and women for predicting normal pulmonary function for young adults in South India. The values were similar to those reported for subjects from Western India and lower than those reported for North Indians and caucasians.  相似文献   
8.
With the development of conformal radiotherapy, particularly intensity modulated radiation therapy (IMRT), there is a clear need for multidimensional dosimeters. A commercial polymerizing gel, BANG-2 gel (MGS Research, Inc., Guilford, CT), has recently been developed that shows potential as a multi-dimensional dosimeter. This study investigates and characterizes the noise and magnetic resonance (MR) artifacts from imaging BANG-2 gels. Seven cylindrical vials (4 cm diam, 20 cm length) were irradiated end on in a water bath and read using MRI (B0=1.5 T, TE=20 ms/100 ms, TR=3000 ms). The gel calibration compared the measured depth-dose distributions in water against the change in solvent-proton R2 relaxivity of the gel. A larger vial (13 cm diam, 14 cm length) was also irradiated to test the calibration accuracy in a vial of sufficient volume for dose distribution measurements. The calibration curve proved accurate to within 1.3% in determining the depth dose measured by the larger vial. An investigation of the voxel-to-voxel (IXIX 3 mm3) noise and sensitivity response curve showed that the voxel-to-voxel variation dominated the dose measurement uncertainty. The voxel-to-voxel standard deviation ranged from 0.2 Gy for the unirradiated gel to 0.7 Gy at 20 Gy. Slice-to-slice R2 magnitude deviations were also observed corresponding to 0.2 Gy. These variations limited the overall accuracy of the gel dose measurements and warrant an investigation of more accurate MR readout sequences.  相似文献   
9.
The behavior of Shigella flexneri ipaH mutants was studied in human monocyte-derived macrophages (HMDM), in 1-day-old human monocytes, and in J774 mouse macrophage cell line. In HMDM, strain pWR700, an ipaH(7.8) deletion mutant of S. flexneri 2a strain 2457T, behaved like the wild-type strain 2457T. This strain caused rapid host cell death by oncosis, and few bacterial CFU were recovered after incubation in the presence of gentamicin as previously described for 2457T-infected HMDM. However, analysis of bacterial compartmentalization within endocytic vacuoles with gentamicin and chloroquine indicated that more pWR700 than 2457T was present within the endocytic vacuoles of HMDM, suggesting that ipaH(7.8) deletion mutant transited more slowly from the vacuoles to the cytoplasm. In contrast to findings with HMDM, CFU recovered from pWR700-infected mouse J774 cells were 2 to 3 logs higher than CFU from 2457T-infected J774 cells. These values exceeded CFU recovered after infection of J774 cells with plasmid-cured avirulent strain M4243A1. Incubation with gentamicin and chloroquine clearly showed that pWR700 within J774 cells was mostly present within the endocytic vacuoles. This distribution pattern was similar to that seen with M4243A1 and contrasted with the pattern seen with 2457T. Complementation of pWR700 with a recombinant clone expressing ipaH(7. 8) restored the intracellular distribution of bacteria to that seen with the wild-type strain. Strains with deletions in ipaH(4.5) or ipaH(9.8), however, behaved like 2457T in both HMDM and J774 cells. The distribution profile of pWR700 in 1-day-old monocytes was similar to that seen in J774 cells. Like infected J774 cells, 1-day-old human monocytes demonstrated apoptosis upon infection with virulent Shigella. These results suggest that a role of the ipaH(7. 8) gene product is to facilitate the escape of the virulent bacteria from the phagocytic vacuole of monocytes and macrophages.  相似文献   
10.
Shigellosis is a major cause of infant morbidity and mortality in developing countries. To find immunological correlates of specific protection against shigellosis, we examined chronological samples of sera, stool extracts, duodenal aspirates, and saliva samples from 39 adults and 22 children with shigellosis from Peru for the presence of specific antibody to invasion plasmid antigens (Ipa) common to all virulent Shigella strains, by using both a whole-organism enzyme-linked immunosorbent assay (ELISA) and a Western blot (immunoblot) assay. Antibody responses to lipopolysaccharide (LPS) from Shigella serotypes both homologous and heterologous to the infecting strain were also determined by ELISA. ELISAs showed that the highest serum immunoglobulin G (IgG) antibody titers to Shigella whole organisms both with and without surface Ipa were found in adults and malnourished children, the two groups with the shortest and longest durations of disease, respectively. Mucosal IgA antibody titers to Shigella strains decreased over time to a much greater extent than serum IgG titers, and IgA to Ipa in mucosal secretions was found in adults and well-nourished children but not in malnourished children. The presence of mucosal antibody to Ipa may limit the spread and severity of the infection, as indicated by the prolonged illness observed in malnourished children who have no significant mucosal antibody to Shigella Ipa. Serum antibody titers to the Ipa antigens were high relative to anti-Shigella LPS antibody titers, especially in pediatric patients. In contrast to the anti-Ipa responses observed, no differences in antibody responses to LPS in children compared by nutritional status were found. High levels of serum and mucosal cross-reacting antibody to heterologous serotype LPS were found between Shigella flexneri serotypes 1a and 2a. Different patterns of immune response to Ipa proteins and LPS that may aid in the definition of Shigella antigens important in host protection were observed in adults, well-nourished children, and malnourished children.  相似文献   
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