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Stephen J. McPherson Shirin Hussain Preetika Balanathan Shelley L. Hedwards Birunthi Niranjan Michael Grant Upeksha P. Chandrasiri Roxanne Toivanen Yuzhuo Wang Renea A. Taylor Gail P. Risbridger 《Proceedings of the National Academy of Sciences of the United States of America》2010,107(7):3123-3128
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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Dalton HR Stableforth W Thurairajah P Hazeldine S Remnarace R Usama W Farrington L Hamad N Sieberhagen C Ellis V Mitchell J Hussaini SH Banks M Ijaz S Bendall RP 《European journal of gastroenterology & hepatology》2008,20(8):784-790
AIMS: To report the natural history of autochthonous hepatitis E and hepatitis E virus (HEV) IgG seroprevalence in Southwest England. METHODS: Patients with unexplained hepatitis were tested for hepatitis E and cases followed until recovery or death. Five hundred blood donors, 336 individuals over the age of 60 years and 126 patients with chronic liver disease were tested for HEV IgG. RESULTS: Forty cases of autochthonous hepatitis E (genotype 3) were identified. Hepatitis E was anicteric in 25% of cases and usually caused a self-limiting hepatitis predominantly in elderly Caucasian males. Six of 40 had a significant complication and three patients died, two of who had previously undiagnosed cirrhosis. Hepatitis E shows a seasonal variation with peaks in the spring and summer and no cases in November and December. HEV IgG prevalence increases with age, is more common in men and is 16% in blood donors, 13% in patients with chronic liver disease and 25% in individuals over 60 years. CONCLUSION: Autochthonous hepatitis E is more common than previously recognized, and should be considered in the differential diagnosis in patients with hepatitis, whatever their age or travel history. It carries a significant morbidity and when seen in the context of chronic liver disease carries an adverse prognosis. 相似文献
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Ijaz A Khan 《The American journal of medicine》2002,112(1):58-66
The long QT syndrome is characterized by prolongation of the corrected QT (QTc) interval on the surface electrocardiogram. It is associated with precipitation of a polymorphic ventricular tachycardia, torsade de pointes, which may cause sudden death. The syndrome is a disorder of cardiac repolarization caused by the alterations in the transmembrane potassium and sodium currents. Six genetic loci for the congenital forms of the syndrome have been identified; sporadic cases occur because of spontaneous mutations. Acquired causes of the long QT syndrome include drugs, electrolyte imbalance, toxins, marked bradycardia, subarachnoid hemorrhage, stroke, myocardial ischemia, protein-sparing fasting, autonomic neuropathy, and human immunodeficiency virus disease. Clinical symptoms are the result of the precipitation of torsade de pointes and range from such minor symptoms as dizziness to syncope and sudden death. Short-term treatment is aimed at preventing the recurrences of torsade de pointes and includes intravenous magnesium and potassium administration, temporary cardiac pacing, and correction of electrolyte imbalance; rarely, intravenous isoproterenol is indicated. Long-term management includes use of beta-blockers, permanent pacemaker placement, and cardioverter-defibrillator implantation. Asymptomatic patients are treated if under the age of 40 years at the time of diagnosis. 相似文献
109.
Evaluations of HIV type 1 rev gene diversity and functional domains following perinatal transmission
Ramakrishnan R Hussain M Holzer A Mehta R Sundaravaradan V Ahmad N 《AIDS research and human retroviruses》2005,21(12):1035-1045
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
110.
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