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91.
PURPOSE: To investigate the contribution of HCV infection to insulin resistance in chronic haemodialysis patients. MATERIALS AND METHODS: The study was performed with 55 patients who were on regular haemodialysis therapy three times per week. Of the 55 patients, 34 (20 females and 14 males with an average age of 40.9 years) were anti-HCV (+) and were defined as the HCV (+) group. The remaining 21 patients (8 females and 11 males with an average age of 50 years) were negative for HCV and other viral markers and were defined as the HCV (-) group. BMI of all patients were below 27. Insulin resistance (IR) was calculated according to the HOMA formula and patients were called HOMA-IR (+) if their HOMA scores were higher than 2.5. All of the HOMA-IR (+) patients in both groups were called the HOMA-IR (+) subgroup. None of the patients had a history of drug use or any diseases that were related to insulin resistance except uremia. In both groups and the healthy control group, insulin and glucose levels were studied at three different venous serum samples taken at 5- minute intervals after 12 hours of fasting. Other individual variables were studied at venous serum samples taken after 12 hours of fasting. RESULTS: HOMA scores were (3)2.5 in 22 of 34 HCV (+) patients (64.7%) and 7 of 21HCV (-) patients (33.33%) (p=0.024). Insulin levels of HCV (+) group (13.32 +/- 9.44mIU/mL) were significantly higher than HCV (-) (9.07 +/- 7.39mIU/mL) and the control groups (6.40 +/- 4.94mIU/ mL) (p=0.039 and p=0.021 respectively). HCV (+) patients were younger (40.94 +/- 17.06 and 52.62 +/- 20.64 years, respectively) and had longer dialysis duration (7.18 +/- 3.61 and 2.91 +/- 2.69 years, respectively). Significant positive correlations of HOMA score with insulin (r=0.934, p=0.000) and fasting glucose levels (r=0.379, p=0.043) were found in the HOMA- IR (+) subgroup. Also, a significant positive correlation was found between ALT and insulin levels in the HOMA IR (+) subgroup. C-peptide levels of both HCV (+) and (-) groups were significantly higher than the control group (p < 0.001). There were not any significant correlations between HOMA score and some of the other individual variables including levels of triglyceride, ferritin, ALT, iPTH and Mg in any of the groups. CONCLUSION: In chronic haemodialysis patients; HCV infection is related to a high prevalence of insulin resistance, higher insulin and glucose levels.  相似文献   
92.
OBJECTIVE: To investigate the association between different the left ventricle (LV) geometric patterns and lymphocyte DNA damage in patients with hypertension (HT). METHODS: We studied 84 patients (50.0+/-6.1, years) with HT and 24 healthy control subjects (48.6+/-3.3, years). Four different geometric patterns were identified in patients according to LV mass index and relative wall thickness. Peripheral lymphocyte DNA damages and plasma levels of total antioxidant status (TAS) were determined in all subjects. RESULTS: DNA damage was increased in hypertensive patients compared with control group (p=0.001). The major increase in DNA damage was observed in concentric hypertrophic geometric pattern compared with all other geometric patterns (p<0.001, for all). In multiple linear regression analysis, lymphocyte DNA damage was independently correlated with only TAS (beta=-0.444, p<0.001), but not LV geometry (p>0.05). CONCLUSION: The major increase in lymphocyte DNA damage was observed in concentric hypertrophic geometric pattern. This result may be related to increased oxidative stress.  相似文献   
93.

Purpose

QT dispersion (QTd) was shown to be an independent predictor of mortality in hemodialysis (HD) patients. It may be hypothesized that coronary artery calcification is related to QTd in HD patients because widespread calcification may also involve the cardiac conducting system in these patients. In this study, we aimed to investigate the relationships of corrected QTd (QTcd) with coronary artery calcification score (CACS), carotid plaque score (CPS) and possible influence of these parameters on survival of HD patients.

Methods

Seventy-two HD patients (33 male, 39 female) were enrolled into the study. Mean age of the patients was 44 ± 12 years. Mean follow-up duration was 77 ± 24 months. CACS was determined by computed tomography. QTcd values were calculated as the difference of maximum and minimum QT intervals. Left ventricular mass index (LVMI) and CPS were measured by echocardiography.

Results

QTcd was significantly correlated with CACS (r = 0.233, p = 0.049), CPS (r = 0.354, p = 0.003) and LVMI (p = 0.011, r = 0.299). CPS was found to be significantly higher in the group with high QTcd (>60 ms) [2 (1–4) versus 0 (0–1), p = 0.02]. CACS was significantly correlated with age (r = 0.44, p < 0.001), LVMI (r = 0.52, p < 0.001) and CPS (r = 0.32, p = 0.003). In Kaplan–Meier analysis, survival of patients with high QTcd was significantly lower than the patients with low QTcd. In Cox regression analysis for predicting mortality, age, serum albumin and QTcd were found to be the independent predictors of mortality.

Conclusions

QTcd independently predicted mortality, and it was significantly associated with coronary artery calcification, left ventricular hypertrophy and atherosclerosis in HD patients.  相似文献   
94.
The study was undertaken to search whether pedicle selection for ischemic preconditioning (IP) and duration of global ischemia applied after IP influenced efficacy of IP on flap viability in epigastric adipocutaneous island flap with bilateral pedicles in rat model. In total, 159 rats were divided into one control and three (primary, secondary, or bilateral pedicle) IP treatment groups. IP was performed on different pedicles by three cycles of 10 minutes of pedicle clamping and 10 minutes of release. After IP procedure secondary pedicle was ligated in all groups, and flaps were exposed to 0, 1, 2, 4, or 6 hours of global ischemia by clamping primary pedicle. In control groups, after the perfusion of bipedicled flaps for 1 hour, left pedicle was ligated and flaps were exposed to global ischemia as in IP groups. On day 5 post‐surgery, tissue samples and topographic measurements were taken. No significant differences in semi‐quantitative scorings of polymorphonuclear leukocytes infiltration, chronic inflammation, interstitial edema, neovascularization, VEGF, and CD105 expression levels among groups were found (P > 0.05). Percentages of necrosis were consistently smaller in IP groups compared to controls for the same duration of global ischemia, with exception of the no‐ischemia. Area of necrosis was significantly smaller in primary IP group versus secondary IP group in the absence of global ischemia (P < 0.01). In the presence of global ischemia, both primary and secondary pedicle IP groups had significantly smaller percentage of necrosis than controls (P < 0.05) and there was no significant difference between primary and secondary IP groups (P > 0.05). Thus, IP performed on different pedicles may ameliorate flap survival in a comparable fashion, depending on the duration of global ischemia. Secondary pedicle IP was as effective as primary pedicle IP and may be feasible in free flap transfers. © 2013 Wiley Periodicals, Inc. Microsurgery 34:129–135, 2014.  相似文献   
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97.
Twelve animals (26+/-5 kg) were subjected to the study. In this experimental study, the authors used prostacyclin to inhibit the toxic metabolite release during protamine administration. Animals were divided into two equal groups. Six animals received prostacyclin (the prostacyclin group), and the other six animals did not receive any additional treatment (the control group). All cardiac output and biochemical measurements were evaluated at baseline; before cardiopulmonary bypass; and at 5, 30, and 60 minutes after protamine administration. The measured cardiac index showed that the hearts treated with prostacyclin had satisfactory preservation of left ventricular function. Metabolic and biochemical data showed that the tumor necrosis factor level was raised significantly in the control group (20.75+/-2.2 in the control group and 13.75+/-2.5 pg/mL in the prostacyclin group). Also, E and P selectin levels were elevated in the control group, but this change was less marked in the prostacyclin group. In addition, the intracellular adhesion molecule-1 (ICAM-1) level was significantly higher in the control group than in the prostacyclin group (9.26+/-2.13 in the control group and 5.13+/-1.66 ng/mL in the prostacyclin group). The authors observed that prostacyclin inhibited the toxic mediator release during heparin reversal with protamine. This inhibition is one way of protecting the myocardium reserves from protamine cardiotoxicity.  相似文献   
98.
Sustainable development (SD) as popularized by the Brundtland Commission and politically enshrined in the Sustainable Development Goals has been the explicit focus of sustainability science. While there is broad agreement that the trend of human well-being (W) over time should serve as a sustainability criterion, the literature so far has mostly addressed this in terms of its determinants rather than focusing on W itself. There is broad agreement that an indicator for W should have multiple constituents, clearly going beyond gross domestic product. Here, we propose a tailor-made indicator to serve precisely this purpose following a set of specified desiderata, including its applicability to flexibly defined subnational populations by gender, place of residence, ethnicity, and other relevant characteristics. The indicator, years of good life (YoGL), reflects the evident fact that in order to be able to enjoy any quality of life, one has to be alive and thus is primarily based on life expectancy. However, since mere survival is not considered good enough, life years are counted conditional on meeting minimum standards in two dimensions: the objective dimension of capable longevity (consisting of being out of absolute poverty and enjoying minimal levels of physical and cognitive health) and the subjective dimension of overall life satisfaction. We illustrate the calculation of this indicator for countries and subpopulations at different stages of development and with different degrees of data availability.

Sustainability science refers to the most comprehensive scholarly effort to understand the interactions between natural and social systems in order to assess whether certain developmental pathways can be considered sustainable. This should also include the possible negative effects of environmental changes, such as climate change and biodiversity loss, on future human well-being. In this paper, we propose a tailor-made indicator to assess long-term human well-being as the ultimate end of sustainable development. This indicator, called “years of good life” (YoGL), is designed in such a way that it can be both empirically measured—which is the focus of this paper—and modeled in its long-term future trends—which will be the focus of future work.When assessing changes over time in the well-being of certain human populations (or subpopulations, as defined, e.g., by gender, ethnicity, urban/rural place of residence, or other social groupings), one can focus on the determinants or the constituents of well-being. In sustainability science, thus far, empirical and theoretical research has placed more emphasis on studying the determinants, including environmental services (1), whereas specifying its constituents has received less systematic attention, often leaving us with nothing but the unspecific notion of “utility.” The focus on determinants has led to the concept of “inclusive wealth” (IW) which can be used to assess whether a society is on a sustainable development trajectory in terms of the productive base necessary to maintain a high standard of living in the future (2). However, empirically measuring the values and relative effects of the different capitals determining human well-being remains extremely challenging and “no current attempt to date can be said to be fully inclusive” (3).The idea behind YoGL, on the other hand, is to study sustainability by focusing explicitly on the constituents of well-being and its change over time. In doing so, YoGL avoids several of the pitfalls by which the IW approach is plagued (3, 4). For example, rather than making contestable quantitative assessments of the relative contributions of the different determinants of well-being, the demographic approach underlying YoGL provides numerical values of human well-being directly, expressed as the average number of years of good life a person can expect to live as part of a given subpopulation under the conditions of a specified point in time. Based on the assumed universal nature of its unit of measurement—YoGL lived today in one specific population has the same meaning as YoGL lived in the future or in another population—the indicator has a time-independent meaning. This also avoids the pitfalls of specifying a rate at which to discount future well-being, which have become apparent at least since the debates around the Stern report (5). YoGL allows us to directly compare human well-being across different subpopulations and generations. Moreover, while all estimates of the different determinants of future human well-being are highly sensitive to population growth, as a measure referring to per-person well-being the derivation of YoGL is not directly affected by assumptions about the future trajectory of population size. Finally, as stressed by Dasgupta (6), the nature of determinants can change over time and across places depending on different commodities and technological regimes, whereas the constituents of well-being—as used in YoGL—are arguably shared across space and time.In the following, we will first present the proposed design of the indicator. We will then provide a step-by-step user’s guide for empirically deriving YoGL based on the most appropriate available data source, before offering examples of how it can be calculated based on auxiliary information on populations for which the necessary data are not yet fully available. We will close with a discussion and brief outlook as to what is still needed to use this indicator for the assessment of sustainability.  相似文献   
99.
Recently, increased oxidative stress and impaired antioxidant defense have been suggested as a contributory factor for initiation and progression of complications in diabetes. Although glutathione (GSH) and the enzymes included by glutathione redox cycle have an important role for protection of cells against free radical-mediated damage, they may be susceptible to oxidation themselves. We examined the susceptibility of the GSH pathway to oxidation and inactivation in subjects with well-controlled and poorly controlled insulin-dependent diabetes mellitus (IDDM) versus controls and the effect of glycemic control on this susceptibility. Red blood cells (RBCs) were isolated, RBC level of GSH, activity of glutathione peroxidase (G-Px), and glutathione reductase (G-Red) were measured at the baseline and after a 2-hour incubation with hydrogen peroxide. Significant decreases were observed in the GSH level and in the activity of GSH peroxidase and GSH reductase in all the groups after the incubation with hydrogen peroxide. Maximum decrease was observed in the poorly controlled diabetic group for all parameters. This result indicates that the GSH pathway is susceptible to oxidation; and this susceptibility increases in poorly controlled diabetics. Therefore, insufficient antioxidant defense by the GSH pathway may be one of the factors responsible for development of complications in patients with IDDM.  相似文献   
100.
We report a mentally retarded case with jejunal perforation by ingested chicken bone. Foreign body ingestion constructs a health threat for mentally retarded people. Under guidance of the literature, travel of the bones in the gastrointestinal tract, diagnosis and treatment strategies are evaluated.  相似文献   
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