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91.
Despite continued development of effective HIV treatment, expanded access to care and advances in prevention modalities, HIV‐related stigma persists. We examine how, in the context of a universal HIV‐testing and treatment trial in South Africa and Zambia, increased availability of HIV services influenced conceptualisations of HIV. Using qualitative data, we explore people’s stigma‐related experiences of living in ‘intervention’ and ‘control’ study communities. We conducted exploratory data analysis from a qualitative cohort of 150 households in 13 study communities, collected between 2016 and 2018. We found that increased availability of HIV‐testing services influenced conceptualisations of HIV as normative (non‐exceptional) and the visibility of people living with HIV (PLHIV) in household and community spaces impacted opportunities for stigma. There was a shift in community narratives towards individual responsibility to take up (assumingly) widely available service – for PLHIV to take care of their own health and to prevent onward transmission. Based on empirical data, we show that, despite a growing acceptance of HIV‐related testing services, anticipated stigma persists through the mechanism of shifting responsibilisation. To mitigate the responsibilisation of PLHIV, heath implementers need to adapt anti‐stigma messaging and especially focus on anticipated stigma.  相似文献   
92.
Primary and recurrent cytomegalovirus (CMV) infections frequently cause CMV colitis in immunocompromised as well as inflammatory bowel disease (IBD) patients. Additionally, colitis occasionally occurs upon primary CMV infection in patients who are apparently immunocompetent. In both cases, the underlying pathophysiologic mechanisms are largely elusive - in part due to the lack of adequate access to specimens. We employed the mouse cytomegalovirus (MCMV) model to assess the association between CMV and colitis. During acute primary MCMV infection of immunocompetent mice, the gut microbial composition was affected as manifested by an altered ratio of the Firmicutes to Bacteroidetes phyla. Interestingly, these microbial changes coincided with high-titer MCMV replication in the colon, crypt hyperplasia, increased colonic pro-inflammatory cytokine levels, and a transient increase in the expression of the antimicrobial protein Regenerating islet-derived protein 3 gamma (Reg3γ). Further analyses revealed that murine and human intestinal epithelial cell lines, as well as primary intestinal crypt cells and organoids represent direct targets of CMV infection causing increased cell death. Accordingly, in vivo MCMV infection disrupted the intestinal epithelial barrier and increased apoptosis of intestinal epithelial cells. In summary, our data show that CMV transiently induces colitis in immunocompetent hosts by altering the intestinal homeostasis.  相似文献   
93.
Introduction Women with a pathogenic BRCA1/2 mutation have a markedly increased lifetime risk of developing breast and/or ovarian cancer. The current preventive treatment alternatives that are offered are an intensified breast cancer screening programme and risk-reducing operations. Before deciding on one option, medical and personal factors such as life situation and individual preferences must be weighed carefully. Decision aids are used internationally to support BRCA1/2 mutation carriers during their decision-making process. In this study these are analysed structurally for the first time and their applicability to the German context is examined. Material and Methods A systematic literature search in five electronic databases and a manual search were performed. The identified decision aids were evaluated with regard to formal criteria, medical content and quality. The qualitative assessment used the criteria of the International Patient Decision Aid Standards Collaboration (IPDASi v4.0), which examined various dimensions (e.g., information, probabilities, values). Results Twenty decision aids, which were published between 2003 and 2019 in Australia (n = 4), the United Kingdom (n = 3), Canada (n = 2), the Netherlands (n = 2) and the USA (n = 9), were included. Nine focus on BRCA1/2 mutation carriers and eleven include other risk groups. Eighteen include risk-reducing operations as decision options, 14 list screening methods for breast and/or ovarian cancer, and 13 describe the possibility of pharmacological prevention by means of selective oestrogen receptor modulators or aromatase inhibitors. Nine of the 20 decision aids meet fundamental quality criteria (IPDASi v4.0 qualification criteria). Conclusion International decision aids can serve formally as a basis for a German decision aid for BRCA1/2 mutation carriers. Some of them differ markedly in content from the recommendations of German guidelines. Only a few achieve a high quality. Key words: BRCA1, BRCA2, decision aid, familial breast cancer, familial ovarian cancer  相似文献   
94.
Personalia     

Information

Personalia  相似文献   
95.
96.
OBJECTIVES.: Incidence and risk factors of post-transplant monoclonal gammopathywere studied in renal transplant patients who received theirgrafts between 1982 and 1992 (n=390 grafts). Immunoelectrophoresiswas performed at annual intervals after transplantation. RESULTS.: Forty-six cases of clonal gammopathy were detected: 35 monoclonal,11 bi- or triclonal, with a predominance of IgG and K light-chainsubtypes (IgG, 39; IgA, 3; IgM, 4; K, 35; , 19). Gammopathywas transient in 17 patients (37%). The 5-year cumulative incidenceof gammopathy was 10.7%, much higher than expected for a groupof similar age from the general population. Thirty of the 46gammopathies appeared within the first 2 years of transplantation.Gammopathy never progressed to multiple myeloma during follow-up(median 1 year; (range 0–10)); one patient subsequentlydeveloped Kaposi sarcoma. The 2-year incidence of gammopathywas much higher in patients transplanted in 1989–1991(23/142) than in 1982–1988 (7/248) (P<0.0001). Thiscoincided with the use of quadruple induction immunosuppression(cyclosporin A+azathioprine+prednisone plus either ATG-Fresenius(ATG-F) or OKT3) since 1989. The risk for acquiring gammopathywithin 2 years of transplantation was 14.7% (95% CI 9.2, 20.3%)in patients receiving quadruple induction therapy, but only3.0% (CI 1.2, 6.1%) without such therapy (P<0.0001). Therisk for patients receiving quadruple immunosuppression withOKT3 was 24.5%, significantly greater than with ATG-F (11.8%,P<0.05). Discriminant analysis revealed that the type ofimmunosuppression, but not age or year of transplantation, wereindependent risk factors for gammopathy. CONCLUSIONS.: Monoclonal gammopathy frequently occurs after renal transplantation.Risks are higher for patients receiving quadruple inductionimmunosuppression, particularly if it includes OKT3. Follow-upof these patients is warranted for the early detection of malignanttransformation.  相似文献   
97.
The aim of the present study was to investigate whether amperozide, an antipsychotic drug which possesses anti-aggressive and anxiolytic-like properties, stimulates the secretion of oxytocin and if so, by which receptor mechanism. For this purpose, female or male Sprague Dawley rats were given amperozide (0.5, 2.5 and 5.0 mg/kg IP), ritanserin (5.0 mg/kg), raclopride (2.0 mg/kg) and prazosin (1.0 mg/kg) and were subsequently decapitated for collection of blood (30 and 120 min) after injection. Oxytocin levels were measured with radioimmunoassay. Amperozide 2.5 and 5 mg/kg increased plasma levels of oxytocin significantly (P<0.05 and <0.001). The effect appeared maximal about 30 min after injection of the drug and oxytocin levels were almost back to basal within 120 min. Similar effects were obtained in female and male rats as well as in animals that were freely fed or food deprived for 24 h. CSF levels of oxytocin were also increased. Ritanserin, a 5-HT2-receptor antagonist but not the D2 receptor antagonist raclopride or the 1-adrenoceptor antagonist prazosin stimulated oxytocin release. In addition, clozapine, a neuroleptic with potent HT2-antagonistic properties, was a potent releaser of oxytocin, whereas haloperidol was without effect. A possible role for oxytocin in the behavioural effects of amperozide and clozapine remains to be explored.  相似文献   
98.
Summary The effect of clonidine on the number of 2-adrenoceptors in human platelet membranes, determined by3H-yohimbine binding, was investigatedin vitro andin vivo. Incubation of platelet membranes with clonidine (1–100 µM) for 16 h at 25 °C led to a concentration-dependent decrease in the number of3H-yohimbine binding sites of 10–25%; the affinity of3H-yohimbine to the sites was not changed (KD approximately 3–4 nM). In such desensitized membranes, inhibition of3H-yohimbine binding by clonidine resulted in steep, monophasic displacement curves, which in comparison to the curves from control membranes (IC50 for clonidine 90 nM), were shifted to the right (IC50: 321 nM) and were not affected by 10–4M guanosine-5-triphosphate (GTP).Treatment of 3 hypertensive patients with clonidine (3×150 µg/d for 7 days) reduced blood pressure and heart rate. Simultaneously, both3H-yohimbine binding sites on platelet membranes and plasma catecholamine levels decreased within three days and remained at a reduced level during treatment. After abrupt cessation of clonidine treatment, blood pressure, heart rate and plasma catecholamines rapidly increased, reaching values after two days similar to or higher than those before treatment.3H-yohimbine binding sites, however, initially decreased further before returning to control values. In platelet membranes derived from hypertensive patients treated with clonidine for at least three weeks, GTP (10–4M) had no influence on inhibition of3H-yohimbine binding by (—)-adrenaline and clonidine. It is concluded that clonidine desensitizes 2-adrenoceptors in human platelet membranesin vitro andin vivo. An important step in the desensitization process is the uncoupling of receptor occupancy by agonists and adenylate cyclase activity, as indicated by loss of the regulatory activity of GTP on desensitized membranes. The clonidine withdrawal syndrome may be caused by enhanced release of endogenous catecholamines not adequately regulated by presynaptic 2-adrenoceptors, which have become subsensitive after chronic clonidine treatment.  相似文献   
99.
J Ramlau  E Bock  J Fohlman 《Toxicon》1979,17(1):43-54
Taipoxin from the Australian taipan Oxyuranus s. scutellatus, was detoxified by reaction with p-bromophenacyl bromide and used for preparing antibodies in rabbits. Of its three subunits only the basic α-chain and the acidic γ-chain evoked antibody production, which may suggest that the neutral β-subunit is hidden in the complex. The antibodies did not cross-react with notexin from Notechis s. scutatus nor did taipoxin cross-react with antivenom against Bungarus multicinctus, in accordance with previous findings. Immunochemical studies show a strong interaction between α and γ, whereas α-β- and β-γ-interactions are weak. In animal experiments no protection was observed when antibodies (in excess) were injected i.v. 5 min after taipoxin. This confirms the irreversibility of the attack, perhaps enzymatic (phospholipase), on vital structures in the nerve terminal membranes and emphasizes the urgency of speedy antisera injections in cases of snake-bite in Australia. The modification with p-bromophenacyl bromide ought to be generally useful in the production of high-titre antibodies against snake venoms in a short time and with no ill effects in the antisera-producing animals.  相似文献   
100.
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