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91.
CONTEXT: Most previous studies of clinical presentation and risk factors in early human immunodeficiency virus (HIV) infection have relied on retrospective analyses and referred seroconverters, and thus were subject to possible bias. OBJECTIVES: To apply a method based on measurement of prevalent HIV-1 p24 antigenemia for identification of risk factors for newly acquired HIV infection and to describe the signs and symptoms of acute HIV infection. DESIGN AND SETTING: Nested case-control study in Pune, India. PARTICIPANTS: HIV antibody-negative persons attending 2 sexually transmitted disease (STD) clinics between May 1993 and June 1996. OUTCOME MEASURES: Prevalent p24 antigenemia, risk factors for HIV infection, and clinical symptoms of acute primary HIV infection. RESULTS: Of 3874 HIV antibody-negative persons tested, 58 (1.5%) were p24 antigen positive at initial presentation to the clinics. Unprotected sexual contact with a commercial sex worker (CSW) was reported by 39 (77%) of the 51 p24 antigenemic men, compared with 131 (51 %) of 255 control men (adjusted odds ratio [AOR], 3.4; 95% confidence interval [CI], 1.2-9.6; P=.02). The presence of an active genital ulcer at the time of screening was found in 46 (79%) of the 58 p24 antigenemic men and women, compared with 137 (47%) of the 290 control subjects (AOR, 4.2; 95% CI, 2.0-9.0; P<.001). Signs and symptoms independently associated with p24 antigenemia in HIV antibody-seronegative persons included fever, which was reported by 28 (48%) of the 58 p24 antigenemic subjects, but only 52 (18%) of the 290 control subjects (AOR, 4.7; 95% CI, 2.4-9.0; P<.001). Joint pain was reported by 10% of subjects recently HIV infected, compared with 2% of the control subjects (AOR, 6.5; 95% CI, 1.7-24.8; P=.006). Night sweats were reported by 9% of the p24 antigenemic, but only 1% of the control subjects (AOR, 9.1; 95% CI, 1.7-47.6; P=.009). Overall, fever, joint pain, and/or night sweats were reported in 27 (47%) of the 58 subjects with recent HIV infection. CONCLUSIONS: This systematic case-control study of p24 antigen screening in HIV-seronegative patients attending STD clinics in India identified unprotected sex with a CSW and a genital ulcer as independent risk factors associated with newly acquired HIV infection. In addition, p24 antigen positivity identified recent fever, night sweats, and arthralgias as symptoms that may be predictive of recent HIV infection. In a study of patients attending STD clinics in India, screening for p24 antigen in HIV antibody-negative persons was found to be a reliable and effective research method for determining recent risk behavior and identifying clinical signs of acute primary HIV infection.  相似文献   
92.
The hypothesis that quiescent CD4+ T lymphocytes carrying proviral DNA provide a reservoir for human immunodeficiency virus-type 1 (HIV-1) in patients on highly active antiretroviral therapy (HAART) was examined. In a study of 22 patients successfully treated with HAART for up to 30 months, replication-competent virus was routinely recovered from resting CD4+ T lymphocytes. The frequency of resting CD4+ T cells harboring latent HIV-1 was low, 0.2 to 16.4 per 10(6) cells, and, in cross-sectional analysis, did not decrease with increasing time on therapy. The recovered viruses generally did not show mutations associated with resistance to the relevant antiretroviral drugs. This reservoir of nonevolving latent virus in resting CD4+ T cells should be considered in deciding whether to terminate treatment in patients who respond to HAART.  相似文献   
93.
Compounds N-(6,7-difluoroquinolonyl)-ampicillin (AU-1) and N-(6-fluoroquinolonyl)-ampicillin (FQ-1), synthesized by coupling of the carboxyl group of 6,7-difluoroquinolone (FP-3) and 6-fluoroquinolone (FP4), respectively, with the alpha-amino-group of ampicillin side chain, exhibit antipseudomonal activity similar to and lower acute toxicity than that of norfloxacin, whereas neither ampicillin nor the fluoroquinolone moieties, compound FP-3 or FP4, alone have such activity. Also, AU-1 and FQ-1 are active against tested clinical isolates of Pseudomonas aeruginosa that are highly resistant to norfloxacin, gentamicin, or both. The therapeutic efficacies of FQ-1 and norfloxacin were assessed and compared in neutropenic mice infected with a 90% lethal dose of P aeruginosa. Mice intraperitoneally administered FQ-1 (10 mg/kg) 4, 8, 24, and 48 hours after infection had survival rates as high as 80%, comparable to those of mice treated with norfloxacin at the same dosage and dosing schedule. The study of protoplast formation revealed that FQ-1 did not inhibit cell-wall biosynthesis but did induce cell filamentation of Bacillus subtilis at a level close to its minimal inhibition concentration. Both AU-1 and FQ-1 were able to intercalate into the double-stranded DNA. However, that FQ-1 lost such activity after it was treated with penicillinase suggests that the lactam-ring structure in ampicillin moiety of FQ-1 was hydrolyzed by penicillinase and that the hydrolyzed structure of FQ-1 does not own DNA-intercalation activity.  相似文献   
94.
Sarcoplasmic reticulum (SR) membranes purified from young adult (4-6 months) and aged (26-28 months) Fischer 344 male rat skeletal muscle were compared with respect to the functional and structural properties of the Ca-ATPase and its associated lipids. While we find no age-related alterations in (1) expression levels of Ca-ATPase protein, and (2) calcium transport and ATPase activities, the Ca-ATPase isolated from aged muscle exhibits more rapid inactivation during mild (37 degrees C) heat treatment relative to that from young muscle. Saturation-transfer EPR measurements of maleimide spin-labeled Ca-ATPase and parallel measurements of fatty acyl chain dynamics demonstrate that, accompanying heat inactivation, the Ca-ATPase from aged skeletal muscle more readily undergoes self-association to form inactive oligomeric species without initial age-related differences in association state of the protein. Neither age nor heat inactivation results in differences in acyl chain dynamics of the bilayer including those lipids at the lipid-protein interface. Initial rates of tryptic digestion associated with the Ca-ATPase in SR isolated from aged muscle are 16(+/- 2)% higher relative to that from young muscle. indicating more solvent exposure of a portion of the cytoplasmic domain. During heat inactivation these structural differences are amplified as a result of immediate and rapid further unfolding of the Ca-ATPase isolated from aged muscle relative to the delayed unfolding of the Ca-ATPase isolated from young muscle. Thus age-related alterations in the solvent exposure of cytoplasmic peptides of the Ca-ATPase are likely to be critical to the loss of conformational and functional stability.  相似文献   
95.
96.
Hearing loss from combined exposures among petroleum refinery workers   总被引:2,自引:0,他引:2  
Seventy-three consecutive cases of childhood acute lymphoblastic leukemia (ALL) diagnosed and managed in Queen Mary Hospital over a 10-year period from 1985 to 1994 were retrospectively analysed for their presenting features and treatment outcome. The 48 boys and 25 girls ranged in age from 0.4 to 14.2 years (median: 4.3 years). Bone and joint pain was a relatively common presenting feature besides fever, hepatosplenomegaly and lymphadenopathy. Immunophenotyping of blast cells showed: 51 B-cell precursor ALL, one B-ALL, 10 T-ALL and three myeloid-antigen positive ALL. Eight cases were unclassified since immunophenotyping had not been performed. Out of the 73 patients, treatment outcome was analysed in 20 cases treated with UKALL-VIII regimen and 28 cases treated with either the UKALL-XI regimen or the Hong Kong Children Cancer Study Group (HKCCSG) protocol which was modelled upon UKALL-XI. Although complete remission rates were similar between the two groups, patients treated with the former regimen that was less intensified suffered more relapses than the latter (56 per cent versus 21 per cent, P = 0.04). There were, however, no significant differences both in event-free survival (38.2 +/- 11.2 per cent versus 71.3 +/- 9.3 per cent, P = 0.12) and overall survival (70.0 +/- 10.2 per cent versus 79.6 +/- 8.3 per cent, P = 0.41) between the two groups at 3 years by long-rank test. With the use of risk-directed therapy and improved supportive care, two-thirds of our patients are able to enjoy long-term event-free survival.  相似文献   
97.
98.
Identification of intrauterine drug-exposed newborns with toxicological screening may have benefits including close follow-up of the infant by both medical and social services. Applying specific written guidelines to select newborns for drug testing decreases bias and protects the physicians and hospitals involved. All drugs reported as positive should be confirmed by an appropriate second test. Urine and meconium testing are the best current options for identifying drug-exposed neonates. Urine testing sensitivity is low because of problems encountered in urine collections and the high thresholds used in current urine assays. The disadvantage to meconium testing is the increased labor and time required to work with this material. Testing of newborn hair is unlikely to be widely used until technically less demanding assays become available. Testing of amniotic fluid or gastric lavage is still in the developmental stages. Adopting lower urine assay thresholds for newborn samples would increase sensitivity and would be an appropriate modification of current methodologies.  相似文献   
99.
Respiratory aspiration is a serious potential complication of glyphosate-surfactant herbicide intoxication. From October 1, 1992 to June 30, 1996, we performed laryngeal evaluations in 53 cases to investigate the possible pathophysiological mechanism of glyphosate intoxication. There were 36 cases with significant laryngeal injury. The blood WBC count were significantly higher and the hospital stays were significantly longer in patients with laryngeal injury, when compared with patients with no laryngeal injury (Student t-test, P < 0.005). Laryngeal injury was strongly correlated with aspiration pneumonitis (mean 2 = 4.449, P < 0.05). We concluded that laryngeal injury may be the major cause of aspiration that leads to some degree of morbidity and mortality, following concentrated glyphosate-surfactant herbicide intoxication. Laryngeal survey may be indicated in cases of glyphosate-surfactant intoxication, to evaluate the severity of mucosal injury, and to apply adequate supportive management as early as possible to prevent from aspiration complications and even mortality.  相似文献   
100.
Production of growth factors may provide a mechanism for disease evolution in some leukemias. Interleukin-1 is a plelotropic cytokine with the ability to synergize with other growth factors as well as to stimulate their production and release. Autocrine and/or paracrine secretion of interleukin-1 has been implicated in the pathogenesis of both chronic and acute myelogenous leukemia. Recently, a series of both specific and nonspecific IL-1 inhibitory molecules have been identified. These include IL-1 receptor antagonist, soluble IL-1 receptors, IL-1-converting enzyme inhibitor, IL-4, IL-10 and IL-1-antisense. Early experiments demonstrating the ability of some of these molecules to inhibit acute and chronic myelogenous leukemia growth suggest that clinical trials of these compounds may provide a novel management approach in these malignancies. Here we review the potential biologic and therapeutic role of IL-1 and its inhibitors in the myeloid leukemias.  相似文献   
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