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1.
A bstract Endotoxin activates white blood cells and complement and produces a spectrum of clinical syndromes ranging from fever to septic shock. Although production of endogenous endotoxemia during cardiopulmonary bypass (CPB) has recently been reported, the role of hypothermia on endotoxemia is not clear. In this study, we evaluated the effects of moderate (24–28°C) and mild (32–34°C) hypothermia on blood endotoxin levels. The study population consisted of 20 patients who underwent coronary artery bypass grafting (CABG) with CPB. Moderate systemic hypothermia was applied during aortic cross-clamping in ten patients (group 1) and mild hypothermia in the remaining ten patients (group 2). The mean rectal temperatures were 26.8 ± 1.2°C in group 1 and 33.8 ± 0.8°C in group 2. The blood samples for endotoxin level measurements were obtained before CPB, during aortic cross-clamping, immediately after the release of the cross-clamp, 20 minutes after the release of the cross-clamp, after CPB, and 2 hours postoperatively. There were no endotoxins in any of the samples before CPB, but it was detected after CPB in both groups. The endotoxin levels were significantly higher in group 1 than in group 2. The present study suggests that when hypothermia is the technique of choice, the deleterious effects of endotoxemia on patients with comorbidity must be considered.  相似文献   
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This study examines the potential effects of exposure to South Louisiana sweet crude oil (LSC), Corexit® EC9500A, and dispersed oil on enclosed phytoplankton communities under different nutrient regimes. Three distinct microcosm experiments were conducted for 10 days to assess changes to the structure of natural communities from the Gulf of Mexico as quantified by temporal changes in the biomasses of different phytoplankton groups. Concentration of NO3, Si and PO4 were 0.83, 0.99 and 0.09 μM for the unenriched treatments and 14.07, 13.01 and 0.94 μM for the enriched treatments, respectively. Overall, the contaminants LSC and Corexit® EC9500A led to a decrease in the number of sensitive species and an increase in more resistant species. Phytoplankton communities showed more sensitivity to LSC under nutrient-limited conditions. The addition of nutrients to initially nutrient-limited treatments lessened the inhibitory effect of LSC in the short term. Centric diatoms benefited most from this enrichment, but pennate diatoms demonstrated considerably greater tolerance to crude oil at low crude oil concentrations in nutrient-enriched treatments. Dinoflagellates showed relatively higher tolerance in nutrient-limited treatments and high crude oil concentrations. Corexit® EC9500A inputs significantly increased the toxicity of crude oil. Corexit® EC9500A alone had a highly inhibitory effect at 63 ppm on phytoplankton communities. This study highlights the fact that different nutrient regimes play a major role in determining the shifts of the phytoplankton community in response to exposure to different concentrations of crude oil and dispersant. Determination of the functional equivalence of shifted phytoplankton groups could complement our research and allow for more pertinent extrapolation to real world conditions.  相似文献   
4.
OBJECTIVES: The purpose of our study was to evaluate the significance of polymorphisms in HLA class II genes in coronary artery ectasia (CAE) patients. METHODS AND RESULTS: Twenty-six patients with CAE without associated cardiac defects were enrolled in the study. CAE was defined as luminal dilation of 1.5- to 2.0-fold of normal limits. Ninety-five healthy subjects who were donors for different organ transplantations, were chosen as control group. Physical examination, electrocardiography and chest X-ray were completely normal in these cases. Both the patients and the control group were screened and compared for their HLA class II genotypes. HLA-DR B1*13, DR16, DQ2 and DQ5 genotypes were significantly more frequent in the patient group.When the known risk factors of coronary heart disease were compared in the patients carrying these genotypes with the non-carrying group, no significant differences were encountered. CONCLUSIONS: HLA-DR B1*13, DR16, DQ2 and DQ5 may be associated with the pathogenesis and increase the risk of CAE.  相似文献   
5.
BACKGROUND: Secondary pulmonary hypertension (PH) and cor pulmonale are the major clinical cardiovascular complications affecting prognosis in patients with chronic obstructive pulmonary disease (COPD). It is also known that endothelin-1 (ET-1) is a potent vasoconstrictor peptide produced by the pulmonary vascular endothelium, and ET-1 may be implicated in the pathogenesis of PH. OBJECTIVES: The purpose of this study was to investigate the presence of ET-1 in patients with COPD and to assess the correlation of ET-1 levels in the plasma and bronchoalveolar lavage (BAL) fluid (BALF) in COPD patients with or without PH. METHODS: Twenty-two patients with COPD and 15 healthy controls were enrolled in the study. Peripheral venous blood samples were collected in all patients and controls. BAL was obtained in COPD patients, and ET-1 levels were measured by radioimmunoassay in all plasma and BALF samples. RESULTS: Plasma ET-1 levels were 2.46 +/- 0.55 and 1.70 +/- 0.42 pmol/dl in patients with COPD and controls, respectively (p < 0.0001). Sixteen of the 22 patients with COPD (73%) had PH established by echocardiography. The ET-1 level in these patients amounted to 2.59 +/- 0.50 pmol/dl, and it was 2.10 +/- 0.54 pmol/dl in 6 patients with COPD without PH. In COPD patients with and without PH, BALF ET-1 levels were 0.19 +/- 0.08 and 0.24 +/- 0.01 pmol/dl, respectively (p > 0.05). CONCLUSIONS: These results suggest that ET-1 is detectable in both the peripheral blood and BALF of COPD patients, but the levels do not statistically differ between patients with and without PH.  相似文献   
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Carbohydrate antigen-125 (CA-125) is emerging as a prognostic biomarker of risk in heart failure. In a prospective study, we compared the prognostic values of CA-125 and amino-terminal pro-brain natriuretic peptide (NT-proBNP) in patients with stable heart failure.We enrolled 102 consecutive chronic, stable, systolic-heart-failure patients (68 men and 34 women; median age, 71 yr) from November 2008 through February 2010. We measured baseline NT-proBNP and CA-125 levels and compared their prognostic values. The primary endpoint was all-cause death and other major adverse events, defined as hospitalization for decompensated heart failure or acute coronary syndrome.During a mean follow-up period of 14 ± 2 months, 12 patients died and 35 others sustained major adverse events. We found that CA-125 level significantly correlated with New York Heart Association functional class, pulmonary artery pressure, microalbuminuria, creatine kinase-MB fraction, and hemoglobin, albumin, and NT-proBNP levels. Upon receiver operating characteristic curve analysis, CA-125 and NT-proBNP had similar accuracy in predicting major adverse events and death: for major adverse events, area under the curve (AUC) was 0.699 for CA-125 (P=0.002) and 0.696 for NT-proBNP (P=0.002); for death, AUC was 0.784 for CA-125 (P=0.003) and 0.824 for NT-proBNP (P=0.001). Multivariate Cox regression analysis showed that CA-125 levels greater than 32 U/mL and NT-proBNP levels greater than 5,300 pg/mL had independent prognostic value for major adverse events and death.We conclude that baseline CA-125 and NT-proBNP levels are comparably reliable as heart-failure markers, and that CA-125 can be used for prognosis prediction in heart failure.  相似文献   
8.
Mean platelet volume (MPV) has been recognized as an independent risk factor of hypertension. Hypertensive end-organ damage worsens the prognosis in hypertensive patients. We aimed to investigate the relationship between MPV levels and subclinical end-organ damage in hypertensive patients. One hundred and sixteen hypertensive patients (81 women, 35 men, with a mean age of 53 ± 11) were included in the study. There was no correlation between MPV and left-ventricular mass index (LVMI) (r = 0.145; P = 0.14) or albuminuria (r = 0.009; P = 0.93). Among the individuals that had grade I and grade II retinopathy, MPV levels (8.3 ± 2 fL, 8.2 ± 1.3 fL; P = 0.28) were similar either. We concluded that there was no correlation between MPV and markers of end-organ damage in hypertensive patients.  相似文献   
9.

Purpose

Hyponatremia is a common electrolyte disorder in hospitalized patients. Clinical features, outcome and cost of hyponatremia-associated admission and hospitalization in elderly and very elderly patients are not well known.

Methods

Elderly (>64 years) patients admitted to the emergency department (ED) and hospitalized between January 1, 2010, and December 31, 2010, were evaluated. Hyponatremia was defined as serum sodium level below 135 mmol/L. Hyponatremic patients were divided into two groups: group 1 (n = 150, 65–74 years old) and group 2 (n = 103, >74 years old).

Results

A total of 4,960 patients above 65 years of age admitted to ED and hospitalized were included. Prevalence of ED in group 1 and group 2 was 4.1 % (150/3,651) and 7.8 % (103/1,309), respectively (p < 0.001). Vomiting and diarrhea were the most important complaints. A total of 111 (43.8 %) patients were being treated with renin–angiotensin system (RAS) blockers. Mortality, morbidity and hospital cost increased in parallel to decrease in serum Na+ level and increase in age. Group 2 subjects had not only higher intensive care need (p < 0.01) and mortality rates (p < 0.01), but also higher hospital cost burden (p < 0.05) compared to group 1. Alzheimer’s disease was one of the most common co-morbidity in patients, particularly in group 2 (5.3 % vs. 21.3 %, p < 0.001).

Conclusion

Hyponatremia-associated hospitalization is an important and potentially lethal condition in elderly and very elderly patients. Clinicians should be careful when prescribing RAS blockers and diuretics in elderly patients.  相似文献   
10.

Introduction

We compared the effects of 6 different rotary systems on transportation, canal curvature, centering ratio, surface area, and volumetric changes of curved mesial root canals of mandibular molar via cone-beam computed tomographic (CBCT) imaging.

Methods

Mesiobuccal root canals of 120 mandibular first molars with an angle of curvature ranging from 20°–40° were divided into 6 groups of 20 canals. Based on CBCT images taken before instrumentation, the groups were balanced with respect to the angle and radius of canal curvature. Root canals were shaped with the following systems with an apical size of 25: OneShape (OS) (MicroMega, Besancon, France), ProTaper Universal (PU) F2 (Dentsply Maillefer, Ballaigues, Switzerland), ProTaper Next X2 (Dentsply Maillefer), Reciproc (R) R25 (VDW, Munich, Germany), Twisted File Adaptive (TFA) SM2 (SybronEndo, Orange, CA), and WaveOne primary (Dentsply Tulsa Dental Specialties, Tulsa, OK). After root canal preparation, changes were assessed with CBCT imaging. The significance level was set at P = .05.

Results

The R system removed a significantly higher amount of dentin than the OS, PU, and TFA systems (P < .05). There was no significant difference among the 6 groups in transportation, canal curvature, changes of surface area, and centering ratio after instrumentation.

Conclusions

The 6 different file systems straightened root canal curvature similarly and produced similar canal transportation in the preparation of mesial canals of mandibular molars. R instrumentation exhibited superior performance compared with the OS, TFA, and PU systems with respect to volumetric change.  相似文献   
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