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101.
Prostate cancer (PCa) and benign prostatic hyperplasia (BPH) are androgen-dependent diseases commonly treated by inhibiting androgen action. However, androgen ablation or castration fail to target androgen-independent cells implicated in disease etiology and recurrence. Mechanistically different to castration, this study shows beneficial proapoptotic actions of estrogen receptor–β (ERβ) in BPH and PCa. ERβ agonist induces apoptosis in prostatic stromal, luminal and castrate-resistant basal epithelial cells of estrogen-deficient aromatase knock-out mice. This occurs via extrinsic (caspase-8) pathways, without reducing serum hormones, and perturbs the regenerative capacity of the epithelium. TNFα knock-out mice fail to respond to ERβ agonist, demonstrating the requirement for TNFα signaling. In human tissues, ERβ agonist induces apoptosis in stroma and epithelium of xenografted BPH specimens, including in the CD133+ enriched putative stem/progenitor cells isolated from BPH-1 cells in vitro. In PCa, ERβ causes apoptosis in Gleason Grade 7 xenografted tissues and androgen-independent cells lines (PC3 and DU145) via caspase-8. These data provide evidence of the beneficial effects of ERβ agonist on epithelium and stroma of BPH, as well as androgen-independent tumor cells implicated in recurrent disease. Our data are indicative of the therapeutic potential of ERβ agonist for treatment of PCa and/or BPH with or without androgen withdrawal.  相似文献   
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The human immunodeficiency virus type 1 (HIV-1) rev exons 1 and 2 sequences were analyzed from six mother-infant pairs following perinatal transmission. The rev open reading frame was maintained with a frequency of 93.96% in six mother-infant pairs' sequences. There was a low degree of viral heterogeneity and estimates of genetic diversity in mother-infant pairs' rev sequences. However, the distances of rev sequences between epidemiologically unlinked individuals were greater than in epidemiologically linked mother-infant pairs. Furthermore, phylogenetic parameters revealed that the epidemiologically linked mother-infant pairs were closer evolutionarily to each other as compared with epidemiologically unlinked mother-infant pairs. Both mothers and infants were under positive selection pressure as determined by the ratios of nonsynonymous to synonymous substitutions. The functional domains required for Rev activity, including nuclear export of RNA, RNA binding domain, and nuclear import signals, were conserved in all mother-infant pairs' sequences. The conservation of functional domains of rev and a low degree of heterogeneity following vertical transmission are consistent with an indispensable role of rev in the HIV-1 life cycle.  相似文献   
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OBJECTIVE: To study the frequency of neutropenic febrile patients who present in shock, to evaluate the influence of this presenting feature on response to antibiotic therapy, morbidity, and mortality and to identify discriminating demographic features and clinical characteristics of these individuals. METHODS: Prospectively collected data on all episodes of fever and neutropenia observed in cancer patients who were hospitalized for parenteral antibiotic therapy. RESULTS: Five hundred and seventy-six patients were evaluated; 22 (3.8%) presented in shock. This group of individuals was compared with the remainder. Patients presenting in shock were more likely to be older (P< 0.01) and have progressive unresponsive cancer (P< 0.01). They were also more likely to present with septic appearance (P< 0.01), dehydration (P< 0.01), diarrhoea (P< 0.01), altered mental status (P< 0.01) clinical bleeding (P= 0.02) and dyspnoea (P< 0.01). They more often had anaemia (P< 0.01), thrombocytopenia (P= 0.02) and abnormal liver function tests (P< 0.01). Eight of the 22 patients presenting in shock had documented bacteraemia. Non-bacteraemic microbiological infections were observed in three patients. Five patients had clinical evidence of infection and another five were severely dehydrated and volume depleted. One patient had cardiogenic shock. Three patients were managed with monotherapy, 19 received combination antibiotics as initial empirical therapy. Overall outcome of these patients was extremely poor, particularly those with infectious aetiology. Eighteen (82%) patients expired. CONCLUSION: Neutropenic febrile patients who present in shock have extremely poor outcomes irrespective of type of initial antibiotic therapy. Intense efforts are required to improve their outcome.  相似文献   
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OBJECTIVE: To describe our experience of post-transplant infections in allogeneic stem cell transplants at the Armed Forces Bone Marrow Transplant Centre, Rawalpindi, Pakistan. METHODS: From July 2001 to September 2006, patients with malignant and non-malignant hematological disorders having human leukocyte antigen (HLA)-matched sibling donors were selected for transplant. Pre-transplant infection surveillance was carried out, and strict prophylaxis against infection was observed. After admission to the hospital, patients were kept in protective isolation rooms, equipped with a HEPA filter positive-pressure laminar airflow ventilation system. Bone marrow and/or peripheral blood stem cells were used as the stem cell source. Cyclosporin and prednisolone were used as prophylaxis against graft-versus-host disease (GVHD). The engraftment was monitored with cytogenetic/molecular analysis and change of blood group. Survival was calculated from the date of transplant to death or last follow-up. RESULTS: One hundred and fifty-four patients received allogeneic stem cell transplants from HLA-matched siblings for various hematological disorders at the Armed Forces Bone Marrow Transplant Centre, Rawalpindi, Pakistan between July 2001 and September 2006. Indications for transplant included aplastic anemia (n=66), beta-thalassemia major (n=40), chronic myeloid leukemia (n=33), acute leukemia (n=8), and miscellaneous disorders (n=7). One hundred and twenty patients were male and 34 were female. The median age of the patient cohort was 14 years (range 1 1/4-54 years). One hundred and thirty-six patients and 135 donors were cytomegalovirus (CMV) IgG-positive. One hundred and forty patients (90.9%) developed febrile episodes in different phases of post-transplant recovery. Infective organisms were isolated in 150 microbiological culture specimens out of 651 specimens from different sites of infections (23.0% culture positivity). Post-transplant infections were confirmed in 120 patients (77.9%) on the basis of clinical assessment and microbiological, virological, and histopathological examination. Mortality related to infections was 13.0%. Fatal infections included CMV disease (100% mortality, 6/6), disseminated aspergillosis (66.7% mortality, 4/6), pseudomonas septicemia (42.9% mortality, 9/21), and tuberculosis (25% mortality, 1/4). CONCLUSIONS: More than 90% of our patients developed febrile episodes with relatively low culture yield. The majority of infections were treated effectively, however CMV, aspergillosis, and pseudomonas infections remained problematic with high mortality.  相似文献   
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Introduction:Drug induced oral erythema multiforme a rare clinical entity which involves only the lips and oral mucosa without skin involvement. These lesions are difficult in diagnosing with other oral ulcerative lesions with similar clinical manifestations.Patient concerns:This article presents 2 case reports of Oral erythema multiforme in which drugs were the precipitating factor. Its etiopathogenesis, differential diagnosis and treatment modalities of the disease is discussed.Diagnosis:Based on patient''s complaints, drug history and clinical appearance, provisional diagnosis of drug induced erythema multiforme was considered.Intervention:For case 1, patient was instructed to discontinue usage of drug and prescribed systemic steroid (Prednisolone 10 mg/d) for a week along with germicidal drugs to prevent secondary infection. Medication was tapered to 5 mg/d after first week.For case 2, patient was instructed to discontinue the drug and systemic steroid prednisolone 20 mg /d for 1 week with tapering dose of 10 mg/d for the second week was administered.Outcome:For case 1 and case 2 healing of the lesions were evident on third week of follow up.Conclusion:Medications should be taken under medical supervision. Over the counter drugs might lead to allergic reactions like drug induced oral erythema multiforme, which is a rare variant and needs to be differentiate from other oral ulcerative lesion for prompt management and follow-up.  相似文献   
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