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61.
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This paper reviews the recent literature on HIV in the Caribbean and discusses the challenges faced. HIV incidence in the Caribbean has declined by 49 % in the past decade, coverage of persons living with HIV among those eligible for antiretroviral treatment as per national guidelines was 70 % in 2012, and some countries are meeting the target of virtual elimination of mother-to-child transmission. HIV prevalence in the Caribbean is 1 % with features of both a generalized and concentrated HIV epidemic. HIV prevalence among female sex workers has declined but remains unacceptably high among men who have sex with men. Social and cultural factors, gender norms, and strong stigma associated with HIV and homosexuality contribute to the continued spread of HIV. Caribbean countries and their partners have invested significant resources, creative effort and impressive research in strengthening the HIV response nationally and regionally. However, in order to control the HIV epidemic, leaders at all levels, and the people, must address fundamental structural barriers in society that deny marginalized persons their rights, undermine public health goals, and impede universal access to HIV prevention, treatment, and care.  相似文献   
63.
OBJECTIVE: To investigate the impact of official recommendations regarding the management of latent tuberculosis (TB) infection on the rate of active TB in patients receiving treatment with tumor necrosis factor (TNF) antagonists. METHODS: Data on active TB rates and on screening and treatment of latent TB infection were extracted from the BIOBADASER (Spanish Society of Rheumatology Database on Biologic Products), a registry of patients with rheumatic conditions treated with TNF antagonists. The rates of active TB among the BIOBADASER patients were compared with those in the background Spanish population, and BIOBADASER patients with rheumatoid arthritis (RA) were compared with a cohort of RA patients from the EMECAR (Morbidity and Clinical Expression of Rheumatoid Arthritis) study who were not treated with TNF antagonists and were followed up for 5 years. RESULTS: Active TB developed in 34 patients, of whom 32 started taking TNF antagonists prior to the official recommendations on latent TB infection (pre-OR) and 2 began treatment after the recommendations were issued (post-OR). All cases of TB occurred during treatment with infliximab, and 28 of these patients had RA. Pre-OR, the active TB rate in BIOBADASER patients was 20.9-fold higher than in the background Spanish population, while RA patients in the BIOBADASER had rates 22.6- and 6.2-fold higher than the background and EMECAR populations, respectively. Post-OR, 324 patients with a tuberculin skin test result > or =5 mm and/or chest radiograph findings suggestive of past TB were treated for 9 months with isoniazid (INH). Post-OR, active TB rates among the BIOBADASER patients decreased by 78% (incidence risk ratio [IRR] 0.22, 95% confidence interval [95% CI] 0.03-0.88; P = 0.008), while among RA patients in the BIOBADASER, the rate dropped by 83% and reached the EMECAR rate (IRR 1.0, 95% CI 0.02-8.2). There were no INH treatment-related hospitalizations or deaths. CONCLUSION: Strategies to treat latent TB infection that are tailored to the at-risk population can effectively and safely lessen the likelihood of active TB in patients treated with TNF antagonists.  相似文献   
64.
Interleukin-1 alpha (IL-1 alpha) is a macrophage-derived, multifunctional cytokine that broadly potentiates myelopoiesis and induces the synthesis of hematopoietic colony-stimulating factors (CSF) in vitro and in vivo. To evaluate the possibility for use of IL-1 alpha in ameliorating in vivo bone marrow suppression induced by drugs or radiation, we examined the in vivo effects of the cytokine on erythropoietic and other hematopoietic progenitor cells. Normal mice were treated with a single intraperitoneal (IP) injection of recombinant human IL-1 alpha at varying doses and were assayed at various times post-treatment. By six hours postinjection, a significant suppression of mature erythroid progenitors (CFU-E) was observed in animals treated with IL-1 alpha (0.5 micrograms/mouse), with maximum suppression of CFU-E and peripheral blood reticulocyte counts occurring at 24 hours. Decreases in peripheral blood hematocrit did not occur after a single IL-1 alpha injection but were observed after multiple injections of the cytokine. The suppressive effects of IL-1 alpha on late-stage erythropoiesis were abrogated by simultaneous administration of erythropoietin (EPO). At 48 hours post-treatment, a marked stimulation was observed in the numbers of spleen and marrow immature erythroid (BFU-E), macrophage (CFU-M), granulocyte (CFU-G), granulocyte- macrophage (CFU-GM), and megakaryocyte (CFU-meg) progenitor cells. These results demonstrate the potential use of IL-1 alpha as a generalized stimulator of hematopoiesis and show that the cytokine- induced suppression of late-stage erythropoiesis can be prevented by EPO.  相似文献   
65.
Background : How tissue patterns form in development and regeneration is a fundamental issue remaining to be fully understood. The integument often forms repetitive units in space (periodic patterning) and time (cyclic renewal), such as feathers and hairs. Integument patterns are visible and experimentally manipulatable, helping us reveal pattern formative processes. Variability is seen in regional phenotypic specificities and temporal cycling at different physiological stages. Results: Here we show some cellular/molecular bases revealed by analyzing integument patterns. (1) Localized cellular activity (proliferation, rearrangement, apoptosis, differentiation) transforms prototypic organ primordia into specific shapes. Combinatorial positioning of different localized activity zones generates diverse and complex organ forms. (2) Competitive equilibrium between activators and inhibitors regulates stem cells through cyclic quiescence and activation. Conclusions: Dynamic interactions between stem cells and their adjacent niche regulate regenerative behavior, modulated by multi‐layers of macro‐environmental factors (dermis, body hormone status, and external environment). Genomics studies may reveal how positional information of localized cellular activity is stored. In vivo skin imaging and lineage tracing unveils new insights into stem cell plasticity. Principles of self‐assembly obtained from the integumentary organ model can be applied to help restore damaged patterns during regenerative wound healing and for tissue engineering to rebuild tissues. Developmental Dynamics 244:905–920, 2015. © 2015 Wiley Periodicals, Inc.  相似文献   
66.
Immunoreactive tissue kallikrein was co-localized with prolactin in all the eleven prolactin-secreting adenomas of the human anterior pituitary gland examined in this study. The intracellular distribution of immunoreactivity in the prolactin-secreting cells suggests that tissue kallikrein is located within the Golgi complex of these cells. Both the intracellular hormone-processing action and the kininogenase activity of tissue kallikrein may be of functional importance in human prolactinomas.  相似文献   
67.
OBJECTIVES: To analyze the clinical features of uveitis in psoriatic arthritis (PsA) and to investigate the factors predicting its appearance. PATIENTS AND METHODS: Retrospective cohort study (1991-2000) of 71 patients diagnosed with PsA according to the criteria of Moll and Wright. All patients were studied according to a standard protocol. The group was divided into 3 articular categories: axial, oligoarticular, and polyarticular. Human leukocyte antigen (HLA)-Cw typing was performed by the polymerase chain reaction-sequence specific oligonucleotide probes (PCR-SSOP) method in 65 patients and in 177 healthy donors. HLA-DR typing was done by serologic methods in the 71 patients and in 82 healthy donors from the same racial and geographic origin. The HLA-B27 allele also was tested among the study population. All subjects with possible inflammatory ocular disease received a complete ophthalmologic examination at the Ophthalmology Department of our hospital. Only patients with uveitis were analyzed. Univariate and multivariate analyses were applied. RESULTS: Thirteen patients had uveitis (18% of this series), 4 (31%) had an insidious onset, and the remaining had acute-onset uveitis. Five cases (39%) had bilateral-simultaneous uveitis. Ten (77%) presented with anterior uveitis only, 2 with anterior and posterior pole involvement, and only 1 case with isolated posterior pole involvement. Four patients needed oral corticosteroids; 2 of them also used immunosuppresive drugs. None of our patients developed sequelae or complications. In univariate analysis, uveitis was associated with inflammatory back pain (P =.02), sacroiliac pain (P =.001), syndesmophytes (P =.001), bilateral sacroileitis (P =.0001), HLA-DR13 (P =.002), and HLA-B27 (P =.026). In multivariate analysis, the predictive factors for uveitis were bilateral sacroileitis (OR 17, 95% CI: 3.7-76, P =.0002), HLA-DR13 (OR 24, 95% CI: 3.78-150, P =.0056), and syndesmophytes (OR 9.7, 95% CI: 0.97-97, P =.05). CONCLUSIONS: Insidious onset, bilaterality, posterior pole involvement, and chronicity are common in PsA patients with uveitis. In this study, extensive axial involvement (bilateral sacroileitis and syndesmophytes), and the HLA-DR13 antigen were the best predictors for the appearance of uveitis.  相似文献   
68.
Summary Between 1988 and 1995, 1832 HIV positive patients were evaluated in our institution. We studied the epidemiologic, immunologic and bacteriologic data, laboratory tests, and X-Ray films in those with musculoskeletal infection. We reviewed twenty-one cases of musculoskeletal infection in twenty patients aged 23–35 years (mean 28,6 years, M:F=15:5). In all of them risk factor for HIV was intravenous drug abuse. The number of CD4 positive lymphocytes ranged from 0,003 to 0,5 109/l. Staphylococcus aureus was the organism responsible of the infection in twelve cases, all active intravenous drug abusers at the time the diagnosis was done. The remaining causative agents were: Mycobacterium tuberculosis (3 cases), Candida albicans (2 cases), Salmonella subgroup 1 (1 case), Neisseria gonorrhoeae (1 case), Pseudomona aeruginosa (1 case) and Streptococcus agalactiae (1 case). Fifteen infections were diagnosed between 1988 and 1991 and 6 between 1992 and 1995. Musculoskeletal infectious lesions in HIV positive patients in our country are related in the majority of cases to intravenous drug abuse. In the last four years due to a National medical health care plan conducted to educate this group of people the number of musculoskeletal infections is decreasing.  相似文献   
69.
A subsample (1.6%; n = 13,260) of a healthy Jamaican population of food-handlers, studied by Murphy et al. (1991), who were serologically positive (n = 99) or negative (n = 113) for HTLV-I was investigated for intestinal parasitic infection using coprological methods. Helminth infection included Ascaris lumbricoides (2.8%), Trichuris trichiura (7.1%) and hookworms (6.1%). Entamoeba coli was found in 21.8% of samples, while E. hartmanni, Giardia lamblia, Endolimax nana, Iodamoeba bütschlii and Chilomastix mesnili each occurred in less than 10% of responders. T. trichiura displayed a higher prevalence (10.6 vs 3%) (chi 2 = 4.623; P = 0.03) in the HTLV-I negative group. G. lamblia was detected more frequently among HTLV-I carriers compared to controls (9.1 and 3.5%, respectively), but the association was not statistically significant (chi 2 = 2.825; P = 0.09). Infection with intestinal parasites is likely to occur independent of HTLV-I status: however, possible HTLV-I-induced immunosuppression may lead to higher intensity infections of certain organisms thus facilitating easier detection using parasitological methods. The immunomodulatory potential of HTLV-I infection in the aetiology of non-malignant diseases requires further investigation.  相似文献   
70.
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