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991.
992.
In sub-Saharan Africa, respiratory tract infections (RTI) are the leading cause of serious morbidity and mortality in HIV-infected persons. This study sought to investigate demographic, socioeconomic, and environmental risk factors for pneumonia in a cohort of HIV-infected women. The authors performed a nested case-control study in a cohort of HIV-1-infected adults followed in Nairobi, Kenya. Thirty-nine women who developed pneumonia during the follow-up period were selected as cases, and 66 women who did not develop pneumonia were randomly chosen to serve as control subjects. A questionnaire was administered in subjects' homes that assessed demographics, home environment, and socioeconomic status. Women were followed in the cohort for a median of 36.8 months (range, 27.3-39.3). Adjusting for length of follow-up period, factors associated with lower socioeconomic status (lower monthly spending [OR = 3.2; 95% CI, 1.2-8.4 per 10,000 Kenyan shilling decrease], having no savings [OR = 4.1; 95% CI, 1.4-11.9], less sturdy home construction material such as mud or cement walls [OR = 2.6; 95% CI, 1.1-5.9] or dirt floors [OR = 2.8; 95% CI, 1.0-7.6], and lack of a window in the home [OR = 5.5; 95% CI, 0.9-32.2]) and being widowed (OR = 4.3; 95% CI, 1.2-15.1) or single (OR = 3.3; 95% CI, 1.0-11.2) were associated with an increased risk of pneumonia. In multivariate analysis, widowed (AOR = 5.9; 95% CI, 1.3-26.3), single (AOR = 7.7; 95% CI, 1.6-36.4), and divorced (AOR = 4.5; 95% CI, 1.0-20.1) women, those without savings (AOR = 3.7; 95% CI, 1.2-11.7), and those living in more crowded and contagious conditions (AOR = 1.5; 95% CI, 1.1-2.1) remained at increased risk of pneumonia. If confirmed by prospective investigation, these findings could help identify persons and subpopulations of HIV-infected women with the greatest risk of pneumonia.  相似文献   
993.
We examined the acute stress response associated with having to deliver either bad or good medical news using a simulated physician–patient scenario. Twenty-five healthy medical students were randomly assigned to a bad medical news (BN), a good medical news (GN), or a control group that read magazines during the session. Self-report measures were obtained before and after the task. Blood pressure and heart rate were measured throughout the task period. Four blood samples were obtained across the task period. The BN and GN tasks produced significant increases in self-reported distress and cardiovascular responses compared with the control group. There was also a significant increase in natural killer cell function 10 min into the task in the BN group compared with the control group. The BN task was also somewhat more stressful than the GN task, as shown by the self-report and cardiovascular data. These findings suggest that a simulated physician–patient scenario produces an acute stress response in the physician, with the delivery of bad medical news more stressful than the delivery of good medical news.  相似文献   
994.
Naive non-obese diabetic (NOD/LtJ) mice spontaneously produce natural IgG autoantibodies against self-antigens associated with the experimental autoimmune diseases to which they are susceptible: insulin-dependant diabetes mellitus, systemic lupus erythematosus and experimental autoimmune encephalomyelitis. We discovered recently that NOD/LtJ mice also spontaneously produce IgG antibodies to the acetylcholine receptor (AchR), an antigen that can induce experimental autoimmune myasthenia gravis (EAMG) in susceptible rodents. However, there are no reports indicating that NOD/LtJ mice are susceptible to EAMG. To test whether the presence of spontaneous IgG autoantibodies can predict susceptibility to an autoimmune disease, we challenged NOD/LtJ mice using a standard protocol to induce EAMG. We now report that NOD/LtJ mice developed EAMG, although to a somewhat lesser degree than did C57BL/6 mice, a strain regarded as highly susceptible to the disease. Both strains produced comparable levels of immune antibodies to AchR of the complement-fixing isotypes IgG2a and IgG2b; however, NOD/LtJ mice produced significantly more IgG1. An antigen-specific T cell proliferative response to AchR of the same magnitude was detected in both strains, together with the secretion of similar amounts of IFN-gamma. Thus, NOD/LtJ mice are susceptible to EAMG and disease induction is accompanied by immune responses comparable to those seen in the susceptible strain C57BL/6. These results support the association between specific, natural IgG autoantibodies and susceptibility to the induction of a particular autoimmune disease.  相似文献   
995.
996.
Human herpesvirus 6 and 7 (HHV‐6, HHV‐7) have been associated with several neurologic syndromes and have been detected in nervous tissue from healthy persons; however, only two cases of HHV‐6A have been reported to be associated with intraocular inflammatory disease. Vitreous fluid was tested from 101 patients, including 69 samples from patients with ocular inflammation including CMV retinitis, idiopathic retinitis, iritis, and vitritis, for HHV‐6A, HHV‐6B, and HHV‐7 DNA by PCR. HHV‐6A DNA (4,950 copies per ml) was detected in vitreous fluid from one patient with CMV retinitis, HHV‐6B DNA (10,140 copies per ml) was detected in vitreous fluid from one patient with idiopathic ocular inflammation in the absence of CMV DNA, and HHV‐7 was not detected in any of the vitreous samples. HHV‐6A, HHV‐6B, and HHV‐7 DNA are detectable in less than 2% of vitreous samples in patients with ocular inflammation. J. Med. Virol. 82:996–999, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   
997.
The use of the medicinal leech (Hirudo medicinalis) in promoting venous drainage in tissues whose vitality is threatened by venous congestion and obstruction, especially in plastic and reconstructive surgery, has been complicated by infections caused by Aeromonas spp. These are leech endosymbionts for which patients undergoing hirudotherapy frequently receive systemic chemoprophylaxis. In order to evaluate the possibility of rendering leeches safe for use on patients, H. medicinalis were fed artificially with a 2 g/L arginine solution (used as a phagostimulant) supplemented with ciprofloxacin (100 mg/L). Aeromonads were detected in 57 out of 80 control leeches (71.3%), but in none of the 56 leeches treated with ciprofloxacin (p <0.001). Treated leeches survived for up to 4 months. Tested weekly, 61% of these leeches took human blood for at least 4 weeks after treatment and all remained negative for aeromonads. All water samples in which leeches were kept before treatment were contaminated with Aeromonas spp.; none were detected in any of the NaCl/arginine solutions with which treated animals were fed. Molecular characterization of two phenotypically distinct isolates using gyrB sequencing showed that one clustered tightly with A. veronii and the other was closely related to A. media. Other environmental bacteria and fungi were isolated from 26.5% of treated leeches that had taken a blood meal 1–4 weeks after treatment. Ciprofloxacin reduced the number of leech-associated aeromonads to undetectable levels for extended periods. Most treated leeches were ready to take a blood meal after treatment, suggesting the possibility of using ciprofloxacin-treated leeches instead of chemoprophylaxis in patients undergoing hirudotherapy.  相似文献   
998.
V3 loop is a major neutralizing determinant of the HIV-1 gp120. Using 3D structures of cholera toxin B subunit (CTB), complete V3 in the gp120 context, and V3 bound to a monoclonal antibody (mAb), we designed two V3-scaffold immunogen constructs (V3-CTB). The full-length V3-CTB presenting the complete V3 in a structural context mimicking gp120 was recognized by the large majority of our panel of 24 mAbs. The short V3-CTB presenting a V3 fragment in the conformation observed in the complex with the 447-52D Fab, exhibited high-affinity binding to this mAb. The immunogens were evaluated in rabbits using DNA-prime/protein-boost protocol. Boosting with the full-length V3-CTB induced high anti-V3 titers in sera that potently neutralize multiple HIV virus strains. The short V3-CTB was ineffective. The results suggest that very narrow antigenic profile of an immunogen is associated with poor Ab response. An immunogen with broader antigenic activity elicits robust Ab response.  相似文献   
999.

Objective

Studies suggest that not all patients desire shared decision making, and little is known about decision making around contraception. This study compared decision-making preferences for contraception to preferences for general health among reproductive-aged women.

Methods

257 women receiving abortion care in an urban hospital completed a survey which included questions adapted from the Problem-Solving Decision-Making Scale about their preferences for medical decision making.

Results

Women were significantly more likely to desire autonomous decision making about contraception than about their general health care (50% vs. 19%, p < .001). No patient characteristics were associated with contraceptive decision-making preferences. Women with Medicaid insurance were more likely to desire autonomous decision making about contraception than about general health care (51% vs. 17%, p < .001).

Conclusion

Women desire more autonomy in their contraceptive decisions than in their decisions about general health care.

Practice implications

Health care providers should be attentive to the existence of variation in preferences in decision making across health domains. Contraceptive providers should proactively assess decisional preferences to ensure the most appropriate counseling is provided to each individual.  相似文献   
1000.
The Madin-Darby canine kidney (MDCK) cell line has become the prototypic cell type for studying the mechanisms involved in viral glycoproteins transport and viral assembly in polarized cells. This cell line has been used in our laboratories for studying human immunodeficiency virus (HIV-1), despite the fact that MDCK cells cannot be infected by HIV. In transfected MDCK cells, HIV-1 glycoproteins are specifically transported to the basolateral cell surface where viral budding also mostly occurs. However, this model is of limited use when viral propagation, infection of most cells, or larger production of virions, is needed. The initial objective of this work was thus to establish an MDCK-derived cell line that could be productively infected by HIV-1, in order to pursue our studies on the polarization of viral budding. Expression of both receptor and co-receptor for T-tropic strains of the virus showed that canine cells are rendered permissive once virus binding and entry is allowed. In addition, a reduced infectivity of the viral particles released from the basolateral surface was observed. This observation most likely reflects the interference mediated by CD4 molecules that accumulate at the basolateral domain. Accordingly, this effect was largely prevented when using viruses that down-regulate cell surface CD4 by expression of both viral accessory proteins Vpu and Nef. This is a further evidence that the function of different viral proteins depends of the site of viral budding, which is itself determined by the presence of targeting signal(s) harbored by viral envelope glycoproteins.  相似文献   
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