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1.

Background

Brain synthesis of steroids including sex-steroids is attracting much attention. The endogenous synthesis of corticosteroids in the hippocampus, however, has been doubted because of the inability to detect deoxycorticosterone (DOC) synthase, cytochrome P450(c21).

Methodology/Principal Findings

The expression of P450(c21) was demonstrated using mRNA analysis and immmunogold electron microscopic analysis in the adult male rat hippocampus. DOC production from progesterone (PROG) was demonstrated by metabolism analysis of 3H-steroids. All the enzymes required for corticosteroid synthesis including P450(c21), P450(2D4), P450(11β1) and 3β-hydroxysteroid dehydrogenase (3β-HSD) were localized in the hippocampal principal neurons as shown via in situ hybridization and immunoelectron microscopic analysis. Accurate corticosteroid concentrations in rat hippocampus were determined by liquid chromatography-tandem mass spectrometry. In adrenalectomized rats, net hippocampus-synthesized corticosterone (CORT) and DOC were determined to 6.9 and 5.8 nM, respectively. Enhanced spinogenesis was observed in the hippocampus following application of low nanomolar (10 nM) doses of CORT for 1 h.

Conclusions/Significance

These results imply the complete pathway of corticosteroid synthesis of ‘pregnenolone →PROG→DOC→CORT’ in the hippocampal neurons. Both P450(c21) and P450(2D4) can catalyze conversion of PROG to DOC. The low nanomolar level of CORT synthesized in hippocampal neurons may play a role in modulation of synaptic plasticity, in contrast to the stress effects by micromolar CORT from adrenal glands.  相似文献   

2.

Background

International humanitarian aid workers providing care in emergencies are subjected to numerous chronic and traumatic stressors.

Objectives

To examine consequences of such experiences on aid workers'' mental health and how the impact is influenced by moderating variables.

Methodology

We conducted a longitudinal study in a sample of international non-governmental organizations. Study outcomes included anxiety, depression, burnout, and life and job satisfaction. We performed bivariate regression analyses at three time points. We fitted generalized estimating equation multivariable regression models for the longitudinal analyses.

Results

Study participants from 19 NGOs were assessed at three time points: 212 participated at pre-deployment; 169 (80%) post-deployment; and 154 (73%) within 3–6 months after deployment. Prior to deployment, 12 (3.8%) participants reported anxiety symptoms, compared to 20 (11.8%) at post-deployment (p = 0·0027); 22 (10.4%) reported depression symptoms, compared to 33 (19.5%) at post-deployment (p = 0·0117) and 31 (20.1%) at follow-up (p = .00083). History of mental illness (adjusted odds ratio [AOR] 4.2; 95% confidence interval [CI] 1·45–12·50) contributed to an increased risk for anxiety. The experience of extraordinary stress was a contributor to increased risk for burnout depersonalization (AOR 1.5; 95% CI 1.17–1.83). Higher levels of chronic stress exposure during deployment were contributors to an increased risk for depression (AOR 1·1; 95% CI 1·02–1.20) comparing post- versus pre-deployment, and increased risk for burnout emotional exhaustion (AOR 1.1; 95% CI 1.04–1.19). Social support was associated with lower levels of depression (AOR 0·9; 95% CI 0·84–0·95), psychological distress (AOR = 0.9; [CI] 0.85–0.97), burnout lack of personal accomplishment (AOR 0·95; 95% CI 0·91–0·98), and greater life satisfaction (p = 0.0213).

Conclusions

When recruiting and preparing aid workers for deployment, organizations should consider history of mental illness and take steps to decrease chronic stressors, and strengthen social support networks.  相似文献   

3.
Hwang BF  Jaakkola JJ 《PloS one》2012,7(3):e33949

Background

Few epidemiological studies that have assessed the relation between water disinfection by-products (DBPs) and the risk of stillbirth provide inconsistent results. The objective was to assess the relation between exposure to water disinfection by-products and the risk of stillbirth.

Methods

We conducted a population-based case-control study of 3,289 cases of stillbirth and a random sample of 32,890 control subjects from 396,049 Taiwanese newborns in 2001–2003 using information from the Birth Registry and Waterworks Registry in Taiwan. We compared the risk of stillbirth in four disinfection by-product exposure categories based on the levels of total trihalomethanes (TTHMs) representing high (TTHMs 20+ µg/L), medium (TTHMs 10–19 µg/L), low exposure (TTHMs 5–9 µg/L), and 0–4 µg/L as the reference category. In addition, we conducted a meta-analysis of the results from the present and 5 previous studies focusing on stillbirth.

Findings

In logistic regression analysis adjusting for gender, maternal age, plurality, conception of season and population density of the municipality where the mother lived during pregnancy, the odds ratio (OR) for stillbirth was 1.10 (95% CI 1.00–1.21) for medium exposure and 1.06 (95% 0.96–1.17) for high exposure compared to reference category. In the meta-analysis, the summary odds ratio for stillbirth (1.11, 95% CI: 1.03, 1.19) was consistently elevated.

Conclusions

The present study is consistent with the hypothesis that the risk of stillbirth is related to prenatal exposure to disinfection by-products. This finding on stillbirth is consistent with previous epidemiologic studies, which strengthens the weight of evidence.  相似文献   

4.

Background

Child pedestrian road traffic injuries (RTIs) are an important cause of death and disability in poorer nations, however RTI prevention strategies in those countries largely draw upon studies conducted in wealthier countries. This research investigated personal and environmental risk factors for child pedestrian RTIs relevant to an urban, developing world setting.

Methods

This is a case control study of personal and environmental risk factors for child pedestrian RTIs in San Juan de Miraflores, Lima, Perú. The analysis of personal risk factors included 100 cases of serious pedestrian RTIs and 200 age and gender matched controls. Demographic, socioeconomic, and injury data were collected. The environmental risk factor study evaluated vehicle and pedestrian movement and infrastructure at the sites in which 40 of the above case RTIs occurred and 80 control sites.

Findings

After adjustment, factors associated with increased risk of child pedestrian RTIs included high vehicle volume (OR 7·88, 95%CI 1·97–31·52), absent lane demarcations (OR 6·59, 95% CI 1·65–26·26), high vehicle speed (OR 5·35, 95%CI 1·55–18·54), high street vendor density (OR 1·25, 95%CI 1·01–1·55), and more children living in the home (OR 1·25, 95%CI 1·00–1·56). Protective factors included more hours/day spent in school (OR 0·52, 95%CI 0·33–0·82) and years of family residence in the same home (OR 0·97, 95%CI 0·95–0·99).

Conclusion

Reducing traffic volumes and speeds, limiting the number of street vendors on a given stretch of road, and improving lane demarcation should be evaluated as components of child pedestrian RTI interventions in poorer countries.  相似文献   

5.

Background and Aims

Seed banks are critical in arid ecosystems and ensure the persistence of species. Despite the importance of seed banks, knowledge about their formation and the extent to which a seed bank can recover after severe perturbation remains scarce. If undisturbed, soil seed banks reflect a long vegetation history; therefore, we would expect that new soil seed banks and those of undisturbed soils require long periods to become similar with respect to both density and composition. In contrast, if soil seed banks are only a short- to mid-term reservoir in which long-term accumulation constitutes only a tiny fraction, they will recover rapidly from the vegetation. To shed light on this question, we evaluated seed bank formation in a semi-arid gypsum community.

Methods

Soils from 300 plots were replaced with sterilized soil in an undisturbed semi-arid Mediterranean community. Seasonal changes in seed bank density and composition were monitored for 3 years by comparing paired sterilized and control soil samples at each plot.

Key Results

Differences in seed bank density between sterilized and control soil disappeared after 18 months. The composition of sterilized seed banks was correlated with that of the control plots from the first sampling date, and both were highly correlated with vegetation. Nearly 24 % of the seed bank density could be attributed to secondary dispersal. Most seeds died before emergence (66·41–71·33 %), whereas the rest either emerged (14·08–15·48 %) or persisted in the soil (14·59–18·11 %).

Conclusions

Seed banks can recover very rapidly even under the limiting and stressful conditions of semi-arid environments. This recovery is based mainly on the seed rain at small scales together with secondary dispersal from intact seed banks in the vicinity. These results emphasize the relevance of processes occurring on short spatial scales in determining community structure.  相似文献   

6.

Background

Thyroid-stimulating hormone (TSH) promotes expression of thyroid hormones which are essential for metabolism, growth, and development. Second-line drugs to treat tuberculosis (TB) can cause hypothyroidism by suppressing thyroid hormone synthesis. Therefore, TSH levels are routinely measured in TB patients receiving second-line drugs, and thyroxin treatment is initiated where indicated. However, standard TSH tests are technically demanding for many low-resource settings where TB is prevalent; a simple and inexpensive test is urgently needed.

Methods

As a proof of concept study TSH was measured in routinely collected sera at the University Medical Center Utrecht, Netherlands, using the TSH-CHECK-1 (VEDALAB, Alençon, France), a lateral-flow rapid immunochromatographic assay with a TSH cut-off value of 10 µIU/mL, the standard threshold for initiating treatment. These results were compared with TSH levels measured by a reference standard (UniCel DXi 800 imunoassay system, Beckman Coulter, USA). Sensitivity, specificity, and likelihood ratios were then calculated.

Results

A total of 215 serum samples were evaluated: 107 with TSH values <10 µIU/mL and 108 with values ≥10 µIU/mL. TSH-CHECK-1 test sensitivity was found to be 100.0% (95% CI: 96.6–100.0) and specificity was 76.6% (95% CI: 67.5–84.3). Predictive values (PV) were modelled for different levels of prevalence. For a prevalence of 10% and 50%, the positive PV was 32.2% (95% CI: 25.0–39.7%) and 81.1% (95% CI: 75.0–85.5%), respectively; the negative PV was 100% (95% CI: 98.9–100%) and 100% (95% CI: 91.3–100%) respectively.

Discussion/Conclusions

The TSH-CHECK-1 rapid test was practical and simple to perform but difficult to interpret on weak positive results. All sera with TSH≥10 µIU/mL were correctly identified, but the test lacked sufficient specificity. Given its excellent negative PV in this evaluation, the test shows promise for ruling out hypothyroidism. However, so far it appears that samples testing positive with TSH-CHECK-1 would require confirmation using another method.  相似文献   

7.

Background

Millions of households throughout Bangladesh have been exposed to high levels of arsenic (As) causing various deadly diseases by drinking groundwater from shallow tubewells for the past 30 years. Well testing has been the most effective form of mitigation because it has induced massive switching from tubewells that are high (>50 µg/L) in As to neighboring wells that are low in As. A recent study has shown, however, that shallow low-As wells are more likely to be contaminated with the fecal indicator E. coli than shallow high-As wells, suggesting that well switching might lead to an increase in diarrheal disease.

Methods

Approximately 60,000 episodes of childhood diarrhea were collected monthly by community health workers between 2000 and 2006 in 142 villages of Matlab, Bangladesh. In this cross-sectional study, associations between childhood diarrhea and As levels in tubewell water were evaluated using logistic regression models.

Results

Adjusting for wealth, population density, and flood control by multivariate logistic regression, the model indicates an 11% (95% confidence intervals (CIs) of 4–19%) increase in the likelihood of diarrhea in children drinking from shallow wells with 10–50 µg/L As compared to shallow wells with >50 µg/L As. The same model indicates a 26% (95%CI: 9–42%) increase in diarrhea for children drinking from shallow wells with ≤10 µg/L As compared to shallow wells with >50 µg/L As.

Conclusion

Children drinking water from shallow low As wells had a higher prevalence of diarrhea than children drinking water from high As wells. This suggests that the health benefits of reducing As exposure may to some extent be countered by an increase in childhood diarrhea.  相似文献   

8.
Zhao Y  Zhang J  Zhang J  Wu J 《PloS one》2011,6(1):e16470

Objective

This study was designed to examine the relationship between shortened activated partial thromboplastin time (APTT) and increased fibrinogen values with diabetes mellitus.

Methods

APTT, prothrombin time (PT), fibrinogen, fasting plasma glucose (FPG) and glycosylated hemoglobin A1c (HbA1c) levels were measured in 1,300 patients. Patients were divided into three groups according to their HbA1c and FPG levels.

Results

When participants were grouped according to their HbA1c levels, we found significantly shorter APTT values (26.9±5.6 s) and increased fibrinogen levels (3.1, 1.9–6.3 g/L) in the diabetes group when compared with the other two groups. When participants were grouped according to their FPG levels, we found significantly shorter APTT values (26.9±6.2 s) and increased fibrinogen levels (3.1, 1.8–6.2 g/L) in the diabetes group when compared with the euglycemic group.

Conclusions

Shorter APTT and increased fibrinogen levels might be useful hemostatic markers in patients with diabetes and in patients at high risk for diabetes.  相似文献   

9.
S Zou  F Wu  C Guo  J Song  C Huang  Z Zhu  H Yu  Y Guo  X Lu  Y Ruan 《PloS one》2012,7(7):e40718

Background

Both insufficient and excess iodine may produce thyroid disease. After salt iodization in China, the median urine iodine concentration (UIC) of children aged 8–10 years appeared adequate. However, it is unknown whether dietary changes due to rapid economic development in Shanghai have affected whole population iodine nutrition.

Objective

To assess dietary iodine intake, UIC and the prevalence of thyroid disease in the general population of Shanghai.

Design

A cross-sectional survey was conducted with general participants aged 5–69 years (n = 7,904) plus pregnant and lactating women (n = 380 each) selected by stratified multistage sampling. The iodine concentrations in their salt, drinking water and urine were measured. Daily iodine intake was estimated using the total diet study approach. Serum thyroid hormone concentrations and thyroid-related antibodies were measured and thyroid ultrasonography was performed.

Results

The median iodine concentration in salt was 29.5 mg/kg, and 12.8 µg/L in drinking water. Iodized salt, used by 95.3% of participants, contributed 63.5% of total dietary iodine. Estimated daily iodine intake was 225.96 µg. The median UIC of general participants was 146.7 µg/L; UIC <100 µg/L (iodine insufficiency) was seen in 28.6%; UIC >300 µg/L (iodine excess) in 10.1%. Pregnant women had a median UIC of 135.9 µg/L, with UIC <150 µg/L in 55.4%. Thyroid nodules and subclinical hypothyroidism were found in 27.44% and 9.17%, respectively.

Conclusions

According to published criteria, the current dietary iodine intake in Shanghai was generally sufficient and safe, but insufficient in pregnant women. Thyroid nodules and subclinical hypothyroidism were the commonest thyroid diseases identified.  相似文献   

10.

Objective

Narcolepsy is a severe sleep disorder that is characterized by excessive daytime sleepiness, cataplexies and a tendency towards obesity. Recent discoveries indicate that the major pathophysiology is a loss of hypocretin (orexin) producing neurons due to immunologically mediated degeneration. Visfatin is a recently described proinflammatory adipokine. It is identical to the immune modulating pre-B-cell colony enhancing factor (PBEF). Our study examines the hypothesis that visfatin levels are altered in narcoleptic patients.

Methods

For the analysis, a total of n = 54 patients (n = 18 males and n = 36 females) with the diagnosis of narcolepsy according to DSM-IV and the International Classification of Sleep Disorders were examined (BMI mean 30.3±5.5, age mean 52.5±16.1 years). As a control group 39 unrelated (n = 12 males and n = 27 females) healthy volunteers with no sleep disorder according to DSM-IV were included (BMI mean 28.5±4.6, age mean 51.1±13.6 years). Peripheral visfatin levels were measured using a commercial enzyme immunoassay kit with a measurement range from 0.1–1000 ng/ml. Narcolepsy symptoms, severity and frequency of symptoms as well as the total duration of various aspects of the symptomatology were assessed by unstructured and structured clinical interviews in including the Stanford Center for Narcolepsy Sleep Inventory.

Results

Circulating visfatin was found to be significantly increased in HLA DR2 positive narcoleptic patients compared to controls.

Conclusion

Taken together, our results add to the evidence of disturbed immunological regulation in patients with narcolepsy.  相似文献   

11.

Background

Interleukin-6 (IL-6) may have a protective role in acute liver disease but a detrimental effect in chronic liver disease. It is unknown whether IL-6 is associated with risk of liver-related mortality in humans.

Aims

To determine if IL-6 is associated with an increased risk of all-cause, cardiovascular disease (CVD), cancer, and liver-related mortality.

Methods

A prospective cohort study included 1843 participants who attended a research visit in 1984–87. Multiple covariates were ascertained including serum IL-6. Multivariable-adjusted Cox proportional hazards regression analyses were used to examine the association between serum IL-6 as a continuous (log transformed) variable with all-cause, CVD, cancer, and liver-related mortality. Patients with prevalent CVD, cancer and liver disease were excluded for cause-specific mortality.

Results

The mean (± standard deviation) age and body-mass-index (BMI) of participants was 68 (±10.6) years and 25 (±3.7) Kg/m2, respectively. During the 25,802 person-years of follow-up, the cumulative all-cause, CVD, cancer, and liver-related mortality were 53.1% (N = 978), 25.5%, 11.3%, and 1.3%, respectively. The median (±IQR) length of follow-up was 15.3±10.6 years. In multivariable analyses, adjusted for age, sex, alcohol, BMI, diabetes, hypertension, total cholesterol, HDL, and smoking, one-SD increment in log-transformed serum IL-6 was associated with increased risk of all-cause, CVD, cancer, and liver-related mortality, with hazard ratios of 1.48 (95% CI, 1.33–1.64), 1.38 (95% CI, 1.16–1.65), 1.35 (95% CI, 1.02–1.79), and 1.88 (95% CI, 0.97–3.67), respectively. CRP adjustment attenuated the effects but the association between IL-6 and all-cause and CVD mortality remained statistically significant, independent of CRP levels.

Conclusions

In community-dwelling older adults, serum IL-6 is associated with all-cause, CVD, cancer, and liver-related mortality.  相似文献   

12.

Aims

This study investigated the possible association between hs-CRP as well as hs-CRP changes and rhythm outcome after AF catheter ablation.

Methods

We studied 68 consecutive patients with AF undergoing catheter ablation. hs-CRP levels were measured using commercially available assays before and 6 months after catheter ablation. Serial 7-day Holter ECGs were used to detect AF recurrences.

Results

Early AF recurrence (ERAF, within one week) was observed in 38%, while late AF recurrence (LRAF, between 3 and 6 months) occurred in 18% of the patients. None of the baseline clinical or echocardiographic variables was predictive of ERAF or LRAF. Baseline hs-CRP measured 2.07±1.1 µg/ml and was not associated with ERAF and LRAF. At 6 months, hs-CRP levels were comparable with baseline values (2.14±1.19 µg/ml, p = 0.409) and were also not related with LRAF. However, patients with LRAF showed an hs-CRP increase from 2.03±0.61 to 2.62±1.52 µg/ml (p = 0.028). Patients with an hs-CRP change in the upper tertile (>0.2 µg/ml) had LRAF in 32% as opposed to 11% (p = 0.042) in patients in the lower (<−0.3 µg/ml) or intermediate (−0.3–0.2 µg/ml) tertile.

Conclusions

Changes in hs-CRP but not baseline hs-CRP are associated with rhythm outcome after AF catheter ablation. This finding points to a link between an inflammatory response and AF recurrence in this setting.  相似文献   

13.

Objective

Stress and increased glucocorticoid levels are associated with many neuropsychiatric disorders including schizophrenia and depression. Recently, the role of vascular endothelial factor receptor-2 (VEGFR2/Flk1) signaling has been implicated in stress-mediated neuroplasticity. However, the mechanism of regulation of VEGF/Flk1 signaling under long-term continuous glucocorticoid exposure has not been elucidated.

Material and Methods

We examined the possible effects of long-term continuous glucocorticoid exposure on VEGF/Flk1 signaling in cultured cortical neurons in vitro, mouse frontal cortex in vivo, and in post mortem human prefrontal cortex of both control and schizophrenia subjects.

Results

We found that long-term continuous exposure to corticosterone (CORT, a natural glucocorticoid) reduced Flk1 protein levels both in vitro and in vivo. CORT treatment resulted in alterations in signaling molecules downstream to Flk1 such as PTEN, Akt and mTOR. We demonstrated that CORT-induced changes in Flk1 levels are mediated through glucocorticoid receptor (GR) and calcium. A significant reduction in Flk1-GR interaction was observed following CORT exposure. Interestingly, VEGF levels were increased in cortex, but decreased in serum following CORT treatment. Moreover, significant reductions in Flk1 and GR protein levels were found in postmortem prefrontal cortex samples from schizophrenia subjects.

Conclusions

The alterations in VEGF/Flk1 signaling following long-term continuous CORT exposure represents a molecular mechanism of the neurobiological effects of chronic stress.  相似文献   

14.
YH Chen  YW Wu  WS Yang  SS Wang  CM Lee  NK Chou  RB Hsu  YH Lin  MS Lin  YL Ho  MF Chen 《PloS one》2012,7(8):e44242

Purpose

Heart failure (HF) had been reported with increased risk of hip fractures. However, the relationship between circulating biomarkers and bone mineral density (BMD) in chronic HF remained unclear.

Methods

This is a cross-sectional study which recruited stable chronic HF from registry of the Heart Failure Center of National Taiwan University Hospital. Patients underwent dual-energy x-ray absorptiometry (DEXA) measurements at hip and lumbar spines and biochemical assessments including B-type natriuretic peptide (BNP-32), myostatin, follistatin and osteoprotegerin (OPG).

Results

A total of 115 stable chronic HF individuals with left ventricular ejection fraction (EF) <45% (74% of male, mean age at 59) were recruited with 24 patients in NYHA class I, 73 patients in NYHA class II and 18 patients in NYHA class III. Results of BMD showed that Z scores of hip in NYHA III group (−0.12±1.15) was significantly lower than who were NYHA II (0.58±1.04). Serum OPG was significantly higher in subjects of NYHA III (9.3±4.6 pmol/l) than NYHA II (7.4±2.8 pmol/l) or NYHA I (6.8±3.6 pmol/l) groups. There’s a significant negative association between log transformed serum OPG and trochanteric BMD (R = −0.299, P = 0.001), which remained significant after multivariate analysis.

Conclusions

Our study demonstrated an inverse association between serum OPG and trochanteric BMD in patients with HF. OPG may be a predictor of BMD and an alternative to DEXA for identifying at risk HF patients for osteoporosis.  相似文献   

15.
Zhang Q  Zhang L  Weiner J  Tang J  Chen X 《Annals of botany》2011,107(3):407-413

Background and Aims

Plant biomass–density relationships during self-thinning are determined mainly by allometry. Both allometry and biomass–density relationship have been shown to vary with abiotic conditions, but the effects of biotic interactions have not been investigated. Arbuscular mycorrhizal fungi (AMF) can promote plant growth and affect plant form. Here experiments were carried out to test whether AMF affect plant allometry and the self-thinning trajectory.

Methods

Two experiments were conducted on Medicago sativa L., a leguminous species known to be highly dependent on mycorrhiza. Two mycorrhizal levels were obtained by applying benomyl (low AMF) or not (high AMF). Experiment 1 investigated the effects of AMF on plant growth in the absence of competition. Experiment 2 was a factorial design with two mycorrhizal levels and two plant densities (6000 and 17 500 seeds m−2). Shoot biomass, root biomass and canopy radius were measured 30, 60, 90 and 120 d after sowing. The allometric relationships among these aspects of size were estimated by standardized major axis regression on log-transformed data.

Key Results

Shoot biomass in the absence of competition was lower under low AMF treatment. In self-thinning populations, the slope of the log (mean shoot biomass) vs. log density relationship was significantly steeper for the high AMF treatment (slope = –1·480) than for the low AMF treatment (–1·133). The canopy radius–biomass allometric exponents were not significantly affected by AMF level, but the root–shoot allometric exponent was higher in the low AMF treatment. With a high level of AMF, the biomass–density exponent can be predicted from the above-ground allometric model of self-thinning, while this was not the case when AMF were reduced by fungicide.

Conclusions

AMF affected the importance of below-ground relative to above-ground interactions and changed root vs. shoot allocation. This changed allometric allocation of biomass and altered the self-thinning trajectory.  相似文献   

16.
Yang M  Dong J  Liu H  Li L  Yang G 《PloS one》2011,6(10):e26359

Background

To investigate the effects of short-term continuous subcutaneous insulin infusion (CSII) on plasma fibroblast growth factor-21 (FGF-21) levels in patients with newly diagnosed type 2 diabetes mellitus (nT2DM).

Method

Sixty-eight patients with nT2DM (nT2DM group), and 52 gender-, age- and body mass index (BMI) -matched normal glucose tolerance (NGT group) controls participated in the study. 30 nT2DM patients with FBG≥14.0 mmol/L were treated with CSII for 2 weeks, and were underwent a euglycemic–hyperinsulinemic clamp pre- and post-treatment. Plasma FGF-21 concentrations were measured with a commercial ELISA kit. The relationship between plasma FGF-21 levels and metabolic parameters was also analyzed.

Results

Fasting plasma FGF-21 levels were higher in the nT2DM group than in NGT groups (1.60±0.08 vs. 1.13±0.26 µg/L, P<0.01). In nT2DM patients, fasting plasma FGF-21 concentrations were significantly decreased after CSII treatment for 2 weeks (1.60±0.08 vs.1.30±0.05 µg/L, P<0.05), accompanied by a significant increase in the whole body glucose uptake (M value) and blood glucose control. The changes in plasma FGF-21 levels (ΔFGF-21) were positively associated with the amelioration of insulin resistance shown by the changes in M value.

Conclusion

Plasma FGF-21 level is associated with whole body insulin sensitivity and significantly reduced following short-term CSII treatment.  相似文献   

17.

Background and Aims

Measuring the Al3+ uptake rate across the plasma membrane of intact root cells is crucial for understanding the mechanisms and time-course of Al toxicity in plants. However, a reliable method with the sufficient spatial and temporal resolution to estimate Al3+ uptake in intact root cells does not exist.

Methods

In the current study, fluorescent lifetime imaging (FLIM) analysis was used to quantify Al3+ uptake in the root-cell cytoplasm in vivo. This was performed via the estimation of the fluorescence lifetime of Al–lumogallion {5-chloro-3[(2,4-dihydroxyphenyl)azo]-2-hydroxybenzenesulfonic acid} complexes and measurements of intracellular pH while exposing arabidopsis seedlings to acidic and Al3+ stresses.

Key Results

The lifetime of Al–lumogallion complexes fluorescence is pH-dependent. The primary sites for Al3+ entry are the meristem and distal elongation zones, while Al3+ uptake via the cortex and epidermis of the mature root zone is limited. The maximum rates of Al uptake into the cytoplasm (2–3 µmol m−3 min−1 for the meristematic root zone and 3–7 µmol m−3 min−1 for the mature zone) were observed after a 30-min exposure to 100 µm AlCl3 (pH 4·2). Intracellular Al concentration increased to 0·4 µm Al within the first 3 h of exposure to 100 µm AlCl3.

Conclusions

FLIM analysis of the fluorescence of Al–lumogallion complexes can be used to reliably quantify Al uptake in the cytoplasm of intact root cells at the initial stages of Al3+ stress.Key words: Acid stress, Al3+, aluminium toxicity, Arabidopsis thaliana, low pH, fluorescent lifetime imaging (FLIM), lumogallion  相似文献   

18.
Z Huang  F Fu  Z Zhong  L Zhang  R Xu  X Zhao 《PloS one》2012,7(7):e40577

Objective

To report our experience with Chinese minimally invasive percutaneous nephrolithotomy (Chinese MPCNL) to manage patients with intrarenal stones in solitary kidney, and evaluate the safety, efficiency and feasibility of this technique.

Methods

Forty-one patients with intrarenal stones in solitary kidney underwent Chinese MPCNL in our department from March 2009 to February 2011. Demographic characteristics, operative parameters, number of tracts, stone-free rates (SFRs), stone analyses, hemoglobin levels, nephrostomy tube removal time, hospitalization time, and complications were evaluated. Serum creatinine (Scr) and glomerular filtration rate (GFR) were measured preoperatively, postoperatively at 1 month, and each follow-up visit. The 5-stage classification of chronic kidney disease (CKD) was used according to the National Kidney Foundation guidelines.

Results

The initial stone-free status was achieved in 35 (85.4%) patients after Chinese MPCNL. The mean follow-up time was 16.9±4.7 months (range: 12–24), and the final SFR improved to 97.6% after auxiliary procedures. Among all patients, complex stones were detected in 26 (63.4%) patients, and 9 (22.0%) required multiple tracts. The mean operative time and mean hospitalization time were 71.3±23.5 min (range: 40–139) and 6.1±0.5 days (range: 5–11), respectively. During preoperative period and postoperative period (1 month), Scr were 132.1±41.3 umol/L (range: 78.2–231.4) and 108.9±30.7 umol/L (range: 71.6–136.9), respectively (P<0.05), while GFR were 74.9±24.2 ml/min (range: 35–110) and 83.9±27.4 ml/min (range: 65–110), respectively (P<0.05). According to CKD classification, the renal function was stable, improved, and worse in 29 (70.7%), 11 (26.8%), and 1 (2.5%) patients, compared with the preoperative levels. No patient progressed to end-stage renal disease requiring dialysis.

Conclusions

Our experience with Chinese MPCNL demonstrates that it is safe, feasible and efficient for managing the intrarenal calculi in solitary kidney with a low complication rate. At long-term follow-up, renal function stabilized or even improved in the majority of patients with solitary kidney.  相似文献   

19.

Background

In sub-Saharan Africa, men living with HIV often start ART at more advanced stages of disease and have higher early mortality than women. We investigated gender difference in long-term immune reconstitution.

Methods/Principal Findings

Antiretroviral-naïve adults who received ART for at least 9 months in four HIV programs in sub-Saharan Africa were included. Multivariate mixed linear models were used to examine gender differences in immune reconstitution on first line ART.A total of 21,708 patients (68% women) contributed to 61,912 person-years of follow-up. At ART start,. Median CD4 at ART were 149 [IQR 85–206] for women and 125 cells/µL [IQR 63–187] for men. After the first year on ART, immune recovery was higher in women than in men, and gender-based differences increased by 20 CD4 cells/µL per year on average (95% CI 16–23; P<0.001). Up to 6 years after ART start, patients with low initial CD4 levels experienced similar gains compared to patients with high initial levels, including those with CD4>250cells/µL (difference between patients with <50 cells/µL and those with >250 was 284 cells/µL; 95% CI 272–296; LR test for interaction with time p = 0.63). Among patients with initial CD4 count of 150–200 cells/µL, women reached 500 CD4 cells after 2.4 years on ART (95% CI 2.4–2.5) and men after 4.5 years (95% CI 4.1–4.8) of ART use.

Conclusion

Women achieved better long-term immune response to ART, reaching CD4 level associated with lower risks of AIDS related morbidity and mortality quicker than men.  相似文献   

20.

Background

Outdoor secondhand smoke (SHS) concentrations are usually lower than indoor concentrations, yet some studies have shown that outdoor SHS levels could be comparable to indoor levels under specific conditions. The main objectives of this study were to assess levels of SHS exposure in terraces and other outdoor areas of hospitality venues and to evaluate their potential displacement to adjacent indoor areas.

Methods

Nicotine and respirable particles (PM2.5) were measured in outdoor and indoor areas of hospitality venues of 8 European countries. Hospitality venues of the study included night bars, restaurants and bars. The fieldwork was carried out between March 2009 and March 2011.

Results

We gathered 170 nicotine and 142 PM2.5 measurements during the study. The median indoor SHS concentration was significantly higher in venues where smoking was allowed (nicotine 3.69 µg/m3, PM2.5: 120.51 µg/m3) than in those where smoking was banned (nicotine: 0.48 µg/m3, PM2.5: 36.90 µg/m3). The median outdoor nicotine concentration was higher in places where indoor smoking was banned (1.56 µg/m3) than in venues where smoking was allowed (0.31 µg/m3). Among the different types of outdoor areas, the highest median outdoor SHS levels (nicotine: 4.23 µg/m3, PM2.5: 43.64 µg/m3) were found in the semi-closed outdoor areas of venues where indoor smoking was banned.

Conclusions

Banning indoor smoking seems to displace SHS exposure to adjacent outdoor areas. Furthermore, indoor settings where smoking is banned but which have a semi-closed outdoor area have higher levels of SHS than those with open outdoor areas, possibly indicating that SHS also drifts from outdoors to indoors. Current legislation restricting indoor SHS levels seems to be insufficient to protect hospitality workers – and patrons – from SHS exposure. Tobacco-free legislation should take these results into account and consider restrictions in the terraces of some hospitality venues to ensure effective protection.  相似文献   

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