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Dexamethasone increased alkaline phosphatase levels up to 7-fold in the osteoblast-like rat osteosarcoma cell line ROS 17/2.8. This effect was associated with reduced cell growth and took place over several days in culture. The increase in enzyme activity was dose dependent, (half-maximum near 1 nM, with a hormone specificity suggesting glucocorticoid receptor mediation). Dexamethasone also increased enzyme activity in ROS 2/3 cells, but not in two nonosteoblastic osteosarcoma cell lines, indicating that among these cell lines, the effect is specific for osteoblast-like cells. Moreover, enzyme activity in both control and dexamethasone-treated cells correlated directly with levels of radioimmunoassayable bone-type isoenzyme. Increases in alkaline phosphatase activity in response to dexamethasone were detectable after about 5 h and were inhibited by both actinomycin D and cycloheximide. Thus glucocorticoids appear to increase de novo enzyme synthesis in ROS 17/2.8 cells. Finally, the cAMP-elevating agents PTH, isoproterenol, and 8-bromo-cAMP, which were previously shown to reduce alkaline phosphatase activity in osteoblast-like cells, antagonized the effects of dexamethasone. Moreover, in the presence of dexamethasone, lower concentrations of these agents were required for inhibitory effects on alkaline phosphatase.  相似文献   
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ContextPsychological distress is associated with adverse health outcomes in serious illness and magnified among patients of low socioeconomic status. Aspects of one's culture, such as religion and spirituality, can influence these patients' coping response to distress. Advanced chronic kidney disease (CKD) is a serious illness that disproportionately affects patients of low socioeconomic status, but a theory-based understanding of this group's lived experience of CKD is lacking.ObjectivesWe explored the cognitions, emotions, and coping behaviors of patients with CKD with emphasis on those of low socioeconomic status. We further inquired into any influences of religion or spirituality.MethodsWe interviewed 50 English-speaking or Spanish-speaking adults with advanced CKD from three medical centers in Nashville, Tennessee. Analyses occurred with isolation of themes; development of a coding system; and creation of a conceptual framework using an inductive-deductive approach.ResultsMedian age was 65 years; median annual income was $17,500 per year; and 48% of participants had not progressed beyond high school. Key beliefs (awareness of mortality and lack of control) influenced patients' emotions (existential distress in the form of death anxiety, prognostic uncertainty, and hopelessness) and coping behaviors (acceptance, avoidance, emotion regulation via spirituality, and seeking social support via a religious community).ConclusionIndividuals with advanced CKD and low socioeconomic status lack control over disease progression, experience death anxiety and existential distress, and emphasize spirituality to cope. Our study identifies novel components for a psychotherapeutic intervention for patients with advanced CKD at high risk for adverse health outcomes.  相似文献   
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Clinical Oral Investigations - To analyse the bond quality in dentine post-ageing after salivary contamination and decontamination at different stages of dental adhesive application. A total of...  相似文献   
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We present here a case report of a 27 year old female, with myelodysplatic syndrome suspected to have recurrent hyperhemolytic transfusion reactions (HHTR). Patient was transfusion dependent for ten years and was transfused with leukodepleted and irradiated Packed Red Blood Cells (PRBC). She presented with signs and symptoms of acute intravascular hemolysis, deranged coagulation profile with post transfusion Hb lower than baseline. Post transfusion workup was uneventful. She was managed conservatively with fluid support and methylprednisolone initially. After few uneventful transfusions, patient developed second episode of HHTR with compatible unit.Immunophenotype favored an inflammatory response possibly induced by monocytic lineage. As transfusion dependent, the patient required methylprednisolone as premedication and all subsequent transfusions were uneventful.  相似文献   
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The notion that mitochondria contribute to obesity-induced insulin resistance is highly debated. Therefore, we determined whether obese (BMI 33 kg/m2), insulin-resistant women with polycystic ovary syndrome had aberrant skeletal muscle mitochondrial physiology compared with lean, insulin-sensitive women (BMI 23 kg/m2). Maximal whole-body and mitochondrial oxygen consumption were not different between obese and lean women. However, obese women exhibited lower mitochondrial coupling and phosphorylation efficiency and elevated mitochondrial H2O2 (mtH2O2) emissions compared with lean women. We further evaluated the impact of 12 weeks of aerobic exercise on obesity-related impairments in insulin sensitivity and mitochondrial energetics in the fasted state and after a high-fat mixed meal. Exercise training reversed obesity-related mitochondrial derangements as evidenced by enhanced mitochondrial bioenergetics efficiency and decreased mtH2O2 production. A concomitant increase in catalase antioxidant activity and decreased DNA oxidative damage indicate improved cellular redox status and a potential mechanism contributing to improved insulin sensitivity. mtH2O2 emissions were refractory to a high-fat meal at baseline, but after exercise, mtH2O2 emissions increased after the meal, which resembles previous findings in lean individuals. We demonstrate that obese women exhibit impaired mitochondrial bioenergetics in the form of decreased efficiency and impaired mtH2O2 emissions, while exercise effectively restores mitochondrial physiology toward that of lean, insulin-sensitive individuals.  相似文献   
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OBJECTIVE: To discuss the occurrence of genital chlamydia in developed countries and review the literature assessing the potential risk factors for this sexually transmitted disease. DATA SOURCES: A MEDLINE search was performed for all English citations from 1985 to 2000 that contain the keywords "Chlamydia trachomatis", "chlamydial infections", "risk factors" and "sex behaviour". All relevant references cited in articles that were obtained from the search were also included. DATA EXTRACTION: ALL ARTICLES OBTAINED FROM THE ABOVE SOURCES WERE EXAMINED, AND WERE INCLUDED IN THE REVIEW IF THEY MET THE FOLLOWING CRITERIA: primary study examining sociodemographic or behavioural risk factors associated with genital chlamydial infection using multivariate analysis; study subjects 12 years of age and older; and study setting in a developed country. DATA SYNTHESIS AND CONCLUSIONS: Genital chlamydial infection has become the most commonly reported bacterial infection in North America over the past decade. Thirty-eight cross-sectional studies and six cohort studies were included in the present review. Most studies demonstrated that young men and women are at higher risk of being infected with chlamydia than older subjects. Chlamydia seems to be found in a diverse group of people, and unlike gonorrhea, is not concentrated in low income, minority core groups with high rates of partner change. However, a number of studies have shown that communities with well-established control programs are beginning to demonstrate this pattern. There is no clear evidence that chlamydia is associated with type of partners, contraceptive use, or age at first intercourse. Future research should follow this sexually transmitted disease as it evolves through the epidemiological stages to ensure that preventive and treatment services are reaching those people who are most likely to be infected.  相似文献   
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