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91.
92.
BackgroundFrailty, a clinical state of vulnerability, is associated with subsequent adverse geriatric syndromes in the general population. We examined the long-term impact of frailty on geriatric outcomes among older patients with coronary heart disease.MethodsWe used the National Health and Aging Trends Study, a prospective cohort study linked to a Medicare sample. Coronary heart disease was identified by self-report or International Classification of Diseases (ICD) codes 1-year prior to the baseline visit. Frailty was measured using the Fried physical frailty phenotype. Geriatric outcomes were assessed annually during a 6-year follow-up.ResultsOf the 4656 participants, 1213 (26%) had a history of coronary heart disease 1-year prior to their baseline visit. Compared to those without frailty, subjects with frailty were older (ages ≥75: 80.9% vs 68.9%, P < 0.001), more likely to be female, and belong to an ethnic minority. The prevalence of hypertension, stroke, falls, disability, anxiety/depression, and multimorbidity were much higher in the frail, than nonfrail, participants. In a discrete time survival model, the incidence of geriatric syndromes during 6-year follow-up including 1) dementia, 2) loss of independence, 3) activities of daily living disability, 4) instrumental activities of daily living disability, and 5) mobility disability were significantly higher in the frail than in the nonfrail older patients with coronary heart disease.ConclusionIn patients with coronary heart disease, frailty is a risk factor for the accelerated development of geriatric outcomes. Efforts to identify frailty in the context of coronary heart disease are needed, as well as interventions to limit or reverse frailty status for older patients with coronary heart disease.  相似文献   
93.
Over the 20 years since the criteria for empirically supported treatments (ESTs) were published, standards for synthesizing evidence have evolved and more systematic approaches to reviewing the findings from intervention trials have emerged. Currently, the APA is planning the development of treatment guidelines, a process that will likely take many years. As an intermediate step, we recommend a revised set of criteria for ESTs that will utilize existing systematic reviews of all of the available literature, and recommendations that address the methodological quality, outcomes, populations, and treatment settings included in the literature.  相似文献   
94.
Erythropoietin (Epo), the hormone that is the principal regulator of red blood cell production, interacts with high-affinity receptors on the surface of erythroid progenitor cells and maintains their survival. Epo has been shown to promote cell viability by repressing apoptosis; however, the molecular mechanism involved is unclear. In the present studies we have examined whether Epo acts as a survival factor through the regulation of the bcl-2 family of apoptosis-regulatory genes. We addressed this issue in HCD-57, a murine erythroid progenitor cell line that requires Epo for proliferation and survival. When HCD-57 cells were cultured in the absence of Epo, Bcl-2 and Bcl-XL but not Bax were downregulated, and the cells underwent apoptotic cell death. HCD-57 cells infected with a retroviral vector encoding human Bcl-XL or Bcl-2 rapidly stopped proliferating but remained viable in the absence of Epo. Furthermore, endogenous levels of bcl-2 and bcl-XL were downregulated after Epo withdrawal in HCD-57 cells that remained viable through ectopic expression of human Bcl-XL, further indicating that Epo specifically maintains the expression of bcl-2 and bcl-XL. We also show that HCD-57 rescued from apoptosis by ectopic expression of Bcl-XL can undergo erythroid differentiation in the absence of Epo, demonstrating that a survival signal but not Epo itself is necessary for erythroid differentiation of HCD-57 progenitor cells. Thus, we propose a model whereby Epo functions as a survival factor by repressing apoptosis through Bcl-XL and Bcl-2 during proliferation and differentiation of erythroid progenitors.  相似文献   
95.
Human cytomegalovirus (CMV) infection is often associated with myelosuppression and acute inflammatory reaction in immunocompromised patients. We have previously documented that CMV exposure of bone marrow (BM) stromal cells reduces the capacity of these cells to support hematopoiesis because of a decreased production of colony- stimulating factors. This study examines the potential role of CMV on constitutive and lipopolysaccharide (LPS)-stimulated production of cytokines involved in inflammatory reaction, interleukin-6 (IL-6) and leukemia inhibitory factor (LIF) by BM stromal cells. The release of IL- 6 was already detectable 2 hours post CMV-infection (2.5-fold increase in production) and the cumulative production of IL-6 after 5 days of infection was 23 +/- 1.2 ng/mL (ninefold increase in production). CMV was also able to induce a time-dependent production of LIF that was maximal 8 hours after CMV infection (2.5-fold increase in production). Concomitantly, there was no detectable release of granulocyte colony- stimulating factor (G-CSF) and granulocyte-macrophage CSF (GM-CSF) by CMV-infected stromal cells. The similar IL-6 and LIF production in the presence of polymyxin B ruled out the possibility that this increase could be caused by contamination of the viral stock by endotoxin. In addition, ultraviolet-inactivated virus behaved similarly to live virus and caused the release of IL-6 and LIF. However, heat-inactivated CMV was unable to induce IL-6 and LIF secretion by BM stromal cells. The production of IL-6 and LIF was also evaluated after stimulation by LPS. After 5 days of CMV exposure, the LPS-stimulated production of IL-6 and LIF was significantly lower than uninfected controls. This LPS-induced release of cytokine production was found to be dependent of viral replication. The experiments have shown that CMV is a potent inducer of IL-6 and LIF with differential effect on constitutive and LPS- stimulated cytokine production by stromal cells; we suggest that CMV induction of IL-6 and LIF during the first hours of infection could play a role in CMV-induced inflammatory reaction. Moreover, our results show that human CMV can disturb the balanced cytokine network involved in the regulation of hematopoiesis.  相似文献   
96.
After aortic valve replacement, depressed left ventricular function, as assessed from the preoperative left ventricular ejection fraction, has been reported to improve significantly in patients with aortic stenosis, but to improve little or to a lesser degree In patients with aortic regurgitation. Accordingly, the effect of preoperative left ventricular ejection fraction and other variables on postoperative survival was examined in 229 patients after aortic valve replacement. The preoperative left ventricular ejection fraction, cardiac index and left ventricular end-diastolic pressure were found not to affect the 3 year postoperative survival rate in patients with aortic stenosis and mixed aortic valve disease. However, patients with aortic regurgitation and a left ventricular ejection fraction of less than 0.50 had a significantly poorer 3 year survival rate (64 ± 10 percent) than patients with aortic regurgitation and an ejection fraction of 0.50 or more (91 ± 8 percent) (p <0.02). The 3 year postoperative survival rate in patients with a reduced cardiac index (less than 2.5 liters/min per m2) and aortic regurgitation was also significantly lower (63 ± 10 percent) than the rate in patients with aortic regurgitation and a normal cardiac index (p <0.02). There was less significance in the difference between the 3 year postoperative survival rate of patients with aortic regurgitation whose left ventricular end-diastolic pressure was 15 mm Hg or less and those whose pressure was greater than 15 mm Hg (p <0.05). Thus, it may be advisable to monitor left ventricular ejection fraction noninvasively in patients with aortic regurgitation and to advise aortic valve replacement before the ejection fraction becomes severely depressed.  相似文献   
97.
Mazur  EM; Cohen  JL; Bogart  L 《Blood》1988,71(6):1544-1550
Peripheral blood mononuclear cells from five patients with essential thrombocythemia (ET) were cultured in vitro to evaluate restricted megakaryocytic (CFU-Meg), myeloid (CFU-GM), and erythroid (BFU-E) progenitor cell development. Varying concentrations of aplastic canine serum served as the source of megakaryocyte colony-stimulating activity, and cultured megakaryocyte ploidy distributions were determined by Feulgen staining and microfluorometry. Megakaryocyte colony growth was strikingly abnormal in all five patients evaluated. Four of the 5 had a marked expansion in the concentration of circulating CFU-Meg and 3 of 4 manifested abnormalities in cultured megakaryocyte colony size (2 unusually large and 1 small). Unstimulated megakaryocyte colony growth was substantially increased in three patients. However, the fraction of megakaryocyte progenitors in cell cycle was near or below normal in all instances. Endomitotic megakaryocyte development was disordered in each of the four ET patients in whom it was evaluable. In normal subjects, mean megakaryocyte ploidy values vary biphasically with aplastic canine serum concentration and peak at 13.2 N following 12 to 15 days of culture. In contrast, day 12 mean ploidy values in cultures from the ET patients remained low at all aplastic canine serum concentrations and reached a maximum averaging only 8.4 N. Three patients were evaluated serially at extended culture durations of up to 21 days. The cultured megakaryocyte ploidy was unchanged during this interval for two of the patients. For the third patient, ploidy increased steadily, reaching abnormally high ploidy values by day 21. Progenitor cell expansion was limited to the megakaryocyte line in three patients. However, two patients had substantial increases in CFU-GM, one of whom also had a marked increase in BFU-E. There was no significant unstimulated colony growth by either CFU-GM or BFU-E. These data indicate that ET is usually characterized by an expansion in the concentration of circulating CFU-Meg in vivo which manifest both disordered replication and endoreduplication in vitro.  相似文献   
98.
Background: Screening, brief intervention, and referral to treatment (SBIRT) is recommended as part of routine health care for adolescents as well as adults. In an effort to promote universal SBIRT, the Substance Abuse and Mental Health Services Administration awarded funding to residency programs to develop and implement SBIRT education and training. Our project focused on creating scientifically based, developmentally appropriate strategies and teaching materials for the adolescent age range. This paper describes curriculum development and implementation and presents evaluation data. Methods: Pediatric and child psychiatry residents were trained. The training consisted of 4 activities: (1) case-based teaching modules, (2) role-play of motivational interviewing and brief interventions, (3) mock interviews with trained adolescents, and (4) supervised “hands-on” screening and brief interventions. Main outcome measures included trainee satisfaction, and SBIRT knowledge, perceived self-efficacy, and self- and observer report of use of the SBIRT algorithm. Results: Among 150 total participants completing the SBIRT training modules, nearly all (92.3%) were satisfied/very satisfied with the training modules. Knowledge accuracy immediately post training was high, but declined significantly by the end of the first residency year, with little change across subsequent years of residency. Confidence ratings also declined over time. Use of the SBIRT algorithm during the Adolescent Medicine rotation was high according to trainee self- and faculty observer report. Conclusions: We found evidence of training satisfaction, increased confidence in talking to adolescents about substance use, and widespread use of recommended practices immediately following training. Use of a highly structured algorithm to guide practice, and simple, highly structured brief interventions was a successful training approach, as residents self-reported accurate use of the SBIRT algorithm immediately after training. Knowledge and self-confidence declined over time. It is possible that “booster” sessions and ongoing opportunities to review materials could help residents retain knowledge and skills.  相似文献   
99.
BACKGROUND: Worsening renal function in patients hospitalized for heart failure portends a poor prognosis. However, criteria used to define worsening renal function are arbitrary, and the implications of different definitions remain unclear. We therefore compared the prognostic importance of various definitions of worsening renal function in 1,002 patients hospitalized for congestive heart failure (CHF). METHODS AND RESULTS: The patient population was 49% female, aged 67 +/- 15 years. Twenty-three percent had a prior history of renal failure, 73% had known depressed ejection fraction, and 63% had known CHF. On admission to the hospital, 47% were receiving ACE inhibitors, 22% beta-blockers, 70% diuretics and 6% NAID's. 72% developed increased serum creatinine during the hospitalization, with 20% developing an increase of > or = 0.5 mg/dL. Worsening renal function predicted both in-hospital mortality and length of stay > 10 days. Even an increased creatinine of 0.1 mg/dL was associated with worse outcome. Sensitivity for death decreased from 92% to 65% as the threshold for increased creatinine was raised from 0.1 to 0.5 mg/dL, with specificity increasing from 28% to 81%. At a threshold of a 0.3 mg/dL increase, sensitivity was 81% and specificity was 62% for death and 64% and 65% for length of stay >10 days. Adding a requirement of final creatinine of > or = 1.5 mg/dL improved specificity. CONCLUSIONS: This analysis demonstrates that any detectable decrease in renal function is associated with increased mortality and prolonged hospital stay. This suggests that therapeutic interventions which improve renal function might be beneficial.  相似文献   
100.
In 16 African Americans (blacks, 14 men, 2 women) with average admission mean arterial pressure (MAP, mm Hg) 99.9+/-3.5 (mean+/-SEM), we investigated whether NaCl-induced renal vasoconstriction attends salt sensitivity and, if so, whether supplemental KHCO3 ameliorates both conditions. Throughout a 3-week period under controlled metabolic conditions, all subjects ate diets containing 15 mmol NaCl and 30 mmol potassium (K+) (per 70 kg body wt [BW] per day). Throughout weeks 2 and 3, NaCl was loaded to 250 mmol/d; throughout week 3, dietary K+ was supplemented to 170 mmol/d (KHCO3). On the last day of each study week, we measured renal blood flow (RBF) and glomerular filtration rate (GFR) using renal clearances of PAH and inulin. Ten subjects were salt sensitive (SS) (DeltaMAP >+5%) and 6 salt resistant (SR). In NaCl-loaded SS but not SR subjects, RBF (mL/min/1.73 m2) decreased from 920+/-75 to 828+/-46 (P<0.05); filtration fraction (FF, %) increased from 19. 4+/- to 21.4 (P<0.001); and renal vascular resistance (RVR) (10(3)xmm Hg/[mL/min]) increased from 101+/-8 to 131+/-10 (P<0.001). In all subjects combined, DeltaMAP varied inversely with DeltaRBF (r =-0.57, P=0.02) and directly with DeltaRVR (r = 0.65, P=0.006) and DeltaFF (r = 0.59, P=0.03), but not with MAP before NaCl loading. When supplemental KHCO3 abolished the pressor effect of NaCl in SS subjects, RBF was unaffected but GFR and FF decreased. The results show that in marginally K+-deficient blacks (1) NaCl-induced renal vasoconstrictive dysfunction attends salt sensitivity; (2) the dysfunction varies in extent directly with the NaCl-induced increase in blood pressure (BP); and (3) is complexly affected by supplemented KHCO3, GFR and FF decreasing but RBF not changing. In blacks, NaCl-induced renal vasoconstriction may be a pathogenetic event in salt sensitivity.  相似文献   
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