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51.
Context: Endometrial cancer is associated with metabolic disturbances related to its underlying risk factors, including obesity and diabetes. Identifying metabolite biomarkers associated with endometrial cancer may have value for early detection, risk assessment, and understanding etiology. Objective: The objective of the study was to evaluate the reliable measurement of metabolites in epidemiological studies with nonstandardized blood collection; confirm previously reported correlations of metabolites with body size; and assess differences in metabolite levels between cases and controls. Design: This was the Polish Endometrial Cancer Study (2001-2003). Setting: This study was a population-based case-control study. Patients: Patients included 250 cases and 250 controls. Intervention: The intervention included the measurement of serum metabolite levels of 15 amino acids, 45 acylcarnitines, and nine fatty acids. Main Outcome Measure: The main outcome measure was endometrial cancer. Results: Body mass index was correlated with levels of valine (r = 0.26, P = 3.4 × 10(-5)), octenoylcarnitine (r = 0.24, P = 1.5 × 10(-4)), palmitic acid (r = 0.26, P = 4.4 × 10(-5)), oleic acid (r = 0.28, P = 9.9 × 10(-6)), and stearic acid (r = 0.26, P = 2.9 × 10(-5)) among controls. Only stearic acid was inversely associated with endometrial cancer case status (quartile 4 vs. quartile 1: odds ratio 0.37, 95% confidence interval 0.20-0.69, P for trend = 1.2 × 10(-4)). Levels of the C5-acylcarnitines, octenoylcarnitine, decatrienoylcarnitine, and linoleic acid were significantly lower in cases than controls (odds ratios ranged from 0.21 to 0.38). Conclusions: These data demonstrate that previously reported variations in metabolomic profiles with body mass index can be replicated in population-based studies with nonfasting blood collection protocols. We also provide preliminary evidence that large differences in metabolite levels exist between cases and controls, independent of body habitus. Our findings warrant assessment of metabolic profiles, including the candidate markers identified herein, in prospectively collected blood samples to define biomarkers and etiological factors related to endometrial cancer.  相似文献   
52.

Introduction

Connexin 43 (Cx43) mediates the effect of thyroid hormone on Sertoli cell maturation in vitro. We investigated the influence of triiodothyronine (T3) administration on Cx43 expression in relation to the progress in seminiferous tubule maturation.

Material and methods

Male rats were daily injected with 100 µg T3/kg body weight from birth until postnatal day (pnd) 5 (transient treatment – tT3) or until pnd 15 (continuous treatment – cT3) or solvent – control (C). On pnd 16 serum hormone levels, body and testes weight, seminiferous tubule morphometry, Cx43 immunostaining and germ cell degeneration were investigated. Cx43 expression was also assessed in six 50-day-old adult untreated rats.

Result

tT3 increased 2.6-fold serum level of T3, testes weight, and seminiferous tubule diameter, and induced maturation-like dislocation of Cx43 expression from the apical to the peripheral region of Sertoli cell cytoplasm. In addition, incidence of Cx43-positive tubules declined from 86% in C to 46% after tT3, being similar to the adult value (30% of tubules Cx43-positive). In turn, cT3 increased serum T3 level 12-fold, and decreased body weight. Seminiferous tubules became shortened and distended, Sertoli cell cytoplasm vacuolated, Cx43 expression had minimal intensity and germ cell degeneration increased.

Conclusions

Cx43 might intermediate a short and transient stimulatory effect of T3 on seminiferous tubule maturation that disappeared together with exposure to the toxic effect of a continuously high level of the hormone.  相似文献   
53.
V-containing mesoporous silica with 3D structure was prepared by a hydrothermal procedure using NH4VO3 as the vanadium precursor and with varied reaction mixture pH values (pH = 3 and pH = 5). The combined use of DR UV-vis and H2-TPR techniques confirmed the successful incorporation of vanadium into the structure of the mesoporous silica material. The number of acid sites, evidenced by ammonia TPD, strongly correlates with the vanadium content. Propene oxidation with N2O revealed the noticeable activity of the synthesised vanadium-containing mesoporous materials in epoxidation reactions. The activity of the synthesized vanadosilicates is compared with the performance of vanadium-supported catalysts (on mesoporous silica of 3D structures) prepared by wet-impregnation method. On the basis of TOF analysis indicating the activity of particular vanadium ions, it was evidenced that although the presence of isolated V species is crucial in propene epoxidation, the availability of the active species is of paramount importance for proper vanadium utilization.

Novel promising vanadium catalysts based on mesoporous silica of 3D structure, namely KIT-6, SBA-12, and MCF, for the direct propene epoxidation with N2O.  相似文献   
54.
Hepcidin is the key regulator of iron metabolism. Iron supplementation is often introduced in dialyzed patients to replete or to maintain iron stores, particularly in patients treated with erythropoietic-stimulating agents. The present study was aimed to assess possible relation between hepcidin and erythropoietin therapy, with particular attention being paid to erythropoietin-hyporesponsiveness in hemodialyzed patients. Prohepcidin and hepcidin were studied using commercially available kits from DRG Instruments GmbH, Germany (ELISA method) and Bachem, UK (RIA method). TNFα and IL-6 were studied using kits from and R&D (Abington, UK), and hsCRP was studied using kits from American Diagnostica, USA. Hyporesponsive patients to erythropoietin therapy had significantly lower serum albumin, cholesterol, LDL, hemoglobin, hematocrit, and residual renal function, and significantly higher serum ferritin, hsCRP, IL-6, TNFα, and erythropoietin dose. The difference in serum prohepcidin and hepcidin did not reach statistical significance; however, there was a tendency toward higher values of both prohepcidin and hepcidin in hyporesponsive patients. In conclusion, though hyporesponsiveness to erythropoietin therapy occur in dialyzed patients, it is mainly associated with subclinical inflammation than with hepcidin excess. Further studies are needed to develop a reliable and reproducible assay to elucidate the potential contribution of hepcidin to hyporesponsiveness during erythropoietin therapy.  相似文献   
55.
Aim. The aim of this prospective randomized study was to evaluate the impact of long-term aerobic exercise training on respiratory function, left ventricular systolic function and remodeling in patients with coronary heart disease and ischemic heart failure after successful angioplasty. Design. Patients (n=185) have undergone Doppler echocardiography and ergospirometry. Ninety-five patients practiced 6 month-term aerobic exercise training, less by 10% to their anaerobic threshold. Ninety patients were studied as controls. They were given only drug treatment without training. Measurements were repeated after 6 and 12 months. Results. Training group patients after 6 months showed significant (p<0.05) improvement in exercise capacity, oxygen consumption and ventilating equivalents. The Doppler echocardiographic findings revealed significant (p<0.05) improvement in ejection fraction, left ventricular and atria morphometric data. Improved ergospirometric and echocardiographic data were established after 12 months, too. Conclusions. Long-term aerobic exercise training is an effective and workable measure improving respiratory efficiency, left ventricular systolic function, attenuating negative remodeling and stopping further progression in patients with coronary heart disease and chronic heart failure after successful angioplasty.  相似文献   
56.

Introduction

Current guidelines still recommend the bolus and infusion administration of glycoprotein IIbIIIa inhibitors in patients with high-risk acute coronary syndrome undergoing percutaneous coronary intervention. We sought to evaluate the extent of platelet inhibition by a blocking and bridging strategy with intracoronary abciximab bolus-only administration and oral loading of adenosine diphosphate receptor antagonists.

Patients and methods

Fifty-six consecutive high-risk acute coronary syndrome patients with bolus-only abciximab administration (0.25 mg/kg i.c.) and loading with 600 mg clopidogrel (55%) or 60 mg prasugrel (45%) were included in this study. Platelet aggregation induced by thrombin receptor-activating peptide and adenosine diphosphate was measured by multiple electrode aggregometry up to 7 days.

Results

Thrombin receptor-activating peptide induced platelet aggregation was significantly suppressed for a minimum of 48 h (45 ± 17 U) and returned to a normal range (> 84 U) after 6 days (90 ± 26 U; p < 0.001). Co-medication with prasugrel significantly reduced adenosine diphosphate-induced (p = 0.002) and thrombin receptor-activating peptide-induced (p = 0.02) platelet aggregation compared with clopidogrel throughout the observation period. No stent thrombosis or repeat myocardial infarction occurred at 30-day follow-up.

Conclusions

Immediate blocking of platelet aggregation in high-risk acute coronary syndrome patients by intracoronary abciximab bolus-only administration and bridging to prolonged inhibition via oral blockade of ADP receptors effectively inhibited overall platelet reactivity for at least 48 h, questioning the value of continuous abciximab infusion. Co-medication with prasugrel vs. clopidogrel synergistically augmented platelet inhibition.  相似文献   
57.
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59.
The relationship between pain and increasing age was investigated using data from two different care settings collected on a province-wide basis in Ontario. Home care clients (HC) and complex continuing care patients (CCC) are assessed using the Resident Assessment Instrument-Home Care and Resident Assessment Instrument 2.0 instruments, respectively, as part of normal clinical practice. For this study, the sample was restricted to those aged 65 years and older and totaled 193,158 individuals. Centenarians (those 100 years of age or older) made up 0.41% (n=788) of the sample. Pain was assessed according to a previously validated pain scale embedded in both assessments that uses items on frequency and intensity. Based on 5-year age groups beginning at 65, the mean reported pain score was lower with each increment in age for men and women. Multiple logistic regression models were constructed and the odds ratios for pain in both HC and CCC groups decreased consistently in higher age groups after adjusting for disease diagnoses, cognition, functional status and health indicators. A model that included categories of analgesic medications coded based on the WHO pain ladder showed the relationship persisted after controlling for analgesia. In clinical settings, the oldest old appear to have lower levels of pain compared with the young old after adjusting for a variety of potential confounding variables.  相似文献   
60.
We report details of the first seven equine cases of confirmed West Nile neuroinvasive disease in Austria. The cases presented during summer and autumn of 2016 (n = 2), 2017 (n = 3) and 2018 (n = 2). All horses showed gait abnormalities and 6 of 7 horses exhibited fasciculations and/or tremors, and we provide video recordings of these. Three horses also showed cranial nerve involvement. Following rapid improvement, three horses were discharged. Four horses were euthanized due to the severity of clinical signs and subjected to neuropathological examination. West Nile virus (WNV) lineage 2 nucleic acid was detected in 5 of 7 horses, and WNV‐specific neutralizing antibodies in all 7 horses. In addition, serologic evidence of WNV infection was found in two out of fourteen in‐contact horses. Horses may be considered a sentinel species for human WNV infections, integrating human and veterinary medicine and thus contributing to the one health concept.  相似文献   
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