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1.

Background  

Chronic fatiguing illnesses, including chronic fatigue syndrome (CFS), pose a diagnostic and therapeutic challenge. Previous clinical reports addressed the utilization of health care provided to patients with CFS by a variety of practitioners with other than allopathic training, but did not examine the spectrum of complementary and alternative medicine (CAM) therapies used. This study was designed to measure CAM therapy use by persons with fatiguing illnesses in the United States population.  相似文献   
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In addition to its role in the regulation of artery contraction, Rho kinase (ROCK) was reported to be involved in the cytosolic calcium response to vasoconstrictor agonists in rat aorta and superior mesenteric artery (SMA). However, it remains to be determined whether ROCK also contributes to calcium signaling in resistance arteries, which play a major role in blood pressure regulation. The investigation of the effect of ROCK inhibition on the calcium and contractile responses of rat resistance mesenteric artery (RMA), in comparison with aorta and SMA, indicated that the calcium response to noradrenaline was inhibited by the ROCK inhibitor Y-27632 in aorta and SMA but not in RMA. The effect of Y-27632 on the calcium signal was unaffected by cytochalasin-D. ROCK activation in noradrenaline-stimulated arteries was confirmed by the inhibition of myosin light chain phosphorylation by Y-27632. Moreover, noradrenaline-induced calcium signaling was similarly inhibited by nimodipine in aorta, SMA and RMA, but nimodipine sensitivity of the contraction increased from the aorta to the RMA, suggesting that the contraction was controlled by different sources of calcium. In pressurized RMA, Y-27632 and H-1152 depressed pressure-induced calcium responses and abolished myogenic contraction. These results stress the important differences in calcium signaling between conductance and resistance arteries.  相似文献   
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BACKGROUND: Simian foamy virus (SFV) is an endemic, nonhuman primate (NHP) retrovirus that is transmitted to individuals who work with or hunt NHPs. The cross-species transmission of simian retroviruses is believed to be the etiology of human immunodeficiency virus and human T-lymphotropic virus infections in humans. Although SFV is not pathogenic in the native host, the shared ancestry with other simian retroviruses has brought into question the potential for acquired pathogenicity after cross-species transmission. This study examines whether SFV also shares the traits of transmissibility through the blood supply. STUDY DESIGN AND METHODS: Within a controlled environment, blood from an SFV-infected monkey was transfused into an SFV-uninfected monkey. Evidence of infection, pathogenic effects, immune correlates, and viral shedding were followed for 6 months after transfusion. RESULTS: Molecular evidence of SFV infection manifested 8 weeks after transfusion followed by seroconversion 1 week later. Quantitative analysis demonstrated that the highest level of detectable virus was concomitant with seroconversion followed by establishment of a viral "set-point." Analysis of circulating lymphocytes revealed changes early in infection. Potential routes of transmission of SFV and roles of site-specific immune response are suggested by the late appearance of SFV shedding in the saliva of the transfused animal. CONCLUSION: The blood supply has historically provided a portal through which novel, occult viruses can become disseminated among humans. The demonstration of transmissibility of SFV through whole-blood transfusion, in an NHP model, contributes to the understanding of potential risks associated with blood donation by SFV-infected humans.  相似文献   
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The aim of this multi-center retrospective study was to evaluate the incidence of hyperprogressive disease (HPD) after second-line treatment with pembrolizumab in patients (n = 167) with metastatic non-small-cell lung cancer (NSCLC) whose tumors expressed programmed cell death ligand 1 (PD-L1) in ≥ 1% and to search for hematological and imaging biomarkers associated with its development. Prior to chemotherapy, neutrophil : lymphocyte ratio (NLR1) and platelet : lymphocyte ratio (PLR1), and prior to immunotherapy, NLR2 and PLR2 were retrospectively analyzed. The psoas major muscle area (PMMA) was calculated at the L3 position on computed tomography before chemotherapy (PMMA1) and before immunotherapy (PMMA2) (n = 112). Patients with ∆PMMA (1-PMMA2/PMMA1) × 100 ≥ 10% were considered to have sarcopenia (low muscle mass). After treatment with pembrolizumab on the first computerized tomography (CT) scan evaluation, patients were subdivided as follows as: hyperprogressors (HPs), progressors (Ps), non-progressors (NPs) and pseudoprogressors (PPs). HPs had significantly higher ∆PMMA levels, NLR2 and PLR2 than the other patients. Moreover, in multinomial logistic regression analysis, higher levels of ∆PMMA were associated with a decreased likelihood of being a P [odds ratio (OR) = 0·81; 95% confidence interval (CI) = 0·65–0·99; P = 0·047] or an NP (OR = 0·76; 95% CI = 0·62–0·94; P = 0·012) versus an HP. Higher NLRs tended to decrease the likelihood of being a P versus an HP (OR = 0·66; 95% CI = 0·42–1·06; P = 0·09) and significantly decreased the likelihood of being an NP versus an HP (OR = 0·44; 95% CI = 0·28–0·69; P < 0·0001). Our data suggest that a high pre-immunotherapy NLR2 and the presence of sarcopenia are potential risk factors for the development of HPD.  相似文献   
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We hypothesized that persons with chronic fatigue syndrome (CFS) would have a higher prevalence of metabolic syndrome compared with well controls, and that unwell persons with insufficient symptoms or fatigue for CFS (termed ISF) would have a prevalence of metabolic syndrome intermediate between those with CFS and the controls. We also sought to examine the relationship between metabolic syndrome and measures of functional impairment, fatigue, and other symptoms. Our analysis was based on a population-based case-control study conducted in metropolitan, urban, and rural areas of Georgia, United States, between September 2004 and July 2005. There were 111 persons with CFS, 259 with ISF, and 123 controls. Metabolic syndrome was determined based on having at least 3 of 5 standard risk components (abdominal obesity, high triglycerides, high blood pressure, elevated fasting glucose, and decreased high-density lipids) according to the National Cholesterol Education Program Adult Treatment Panel III definition. Persons with CFS were 2-fold as likely to have metabolic syndrome (odds ratio = 2.12, confidence interval = 1.06, 4.23) compared with the controls. There was a significant graded relationship between the number of metabolic syndrome factors and CFS; each additional factor was associated with a 37% increase in likelihood of having CFS. The association of ISF with metabolic syndrome was weaker (odds ratio = 1.72, confidence interval = 0.94-3.16). Among persons with CFS, the number of metabolic syndrome factors was significantly correlated with worse fatigue on a standardized summary measure of fatigue (r = 0.20, P = .04). In conclusion, CFS was associated with metabolic syndrome, which further exacerbated fatigue.  相似文献   
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