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81.

Background

Few data are available to assess whether a low-moderate reduction in estimated glomerular filtration rates (eGFR) has a role per se on cardiovascular (CV) mortality or other biomarkers such as NT-proBNP allow to explain such association.

Methods and Findings

In a prospective study including 1,645 type 2 diabetic subjects of the population-based Casale Monferrato Study, who had no clinical evidence of heart failure and eGFR >45 ml/min/1.73 m2, we examined 6 years CV mortality. Multivariate Cox proportional hazards modeling were used to estimate the effect of NT-proBNP on the association between eGFR and mortality, independently of baseline CV risk factors, albumin excretion rate (AER) and C-reactive protein (CRP). During follow-up, 327 people died (149 of CV diseases) out of 8334.5 person-years. Compared to eGFR≥90 ml/min/1.73 m2, values of 60–89 and 45–59 ml/min/1.73 m2 conferred a fully adjusted hazard ratios (HRs) of CV mortality of 1.74 (1.08–2.82) and 1.95 (1.03–3.68), respectively. After further adjustment for NT-proBNP, however, HRs were no longer significant (HRs 1.42, 0.83–2.42 and 1.22, 0.59–2.51). In this model, HR for logNT-proBNP was 1.84 (1.52–2.22). Adding NT-proBNP to the model improved the C-statistic of CV mortality from 0.79 (0.76–0.83) to 0.84 (0.81–0.87), yielded an IDI of 0.03 (p = 0.02), and a NRI of 0.44 (p = 0.016).

Conclusions

In diabetic people a modest reduction in renal function increased 6-year CV mortality independently of albuminuria. This association, however, was mainly explained by the effect of NT-proBNP, that remained the strongest prognostic marker for a worse CV outcome, even after adjustment for other CV risk factors and pre-existing CVD.  相似文献   
82.

Introduction

CD4+CD25low/-GITR+ T lymphocytes expressing forkhead box protein P3 (FoxP3) and showing regulatory activity have been recently described in healthy donors. The objective of the study was to evaluate the proportion of CD4+CD25low/-GITR+ T lymphocytes within CD4+ T cells and compare their phenotypic and functional profile with that of CD4+CD25highGITR T lymphocytes in systemic lupus erythematosus (SLE) patients.

Methods

The percentage of CD4+CD25low/-GITR+ cells circulating in the peripheral blood (PB) of 32 patients with SLE and 25 healthy controls was evaluated with flow cytometry. CD4+CD25low/-GITR+ cells were isolated with magnetic separation, and their phenotype was compared with that of CD4+CD25highGITR cells. Regulatory activity of both cell subsets was tested in autologous and heterologous co-cultures after purification through a negative sorting strategy.

Results

Results indicated that CD4+CD25low/-GITR+ cells are expanded in the PB of 50% of SLE patients. Expansion was observed only in patients with inactive disease. Phenotypic analysis demonstrated that CD4+CD25low/-GITR+ cells display regulatory T-cell (Treg) markers, including FoxP3, cytotoxic T-lymphocyte-associated protein 4 (CTLA-4), transforming growth factor-beta (TGF-β), and interleukin (IL)-10. In contrast, CD4+CD25highGITR cells appear to be activated and express low levels of Treg markers. Functional experiments demonstrated that CD4+CD25low/-GITR+ cells exert a higher inhibitory activity against both autologous and heterologous cells as compared with CD4+CD25highGITR cells. Suppression is independent of cell contact and is mediated by IL-10 and TGF-β.

Conclusions

Phenotypic and functional data demonstrate that in SLE patients, CD4+CD25low/-GITR+ cells are fully active Treg cells, possibly representing peripheral Treg (pTreg) that are expanded in patients with inactive disease. These data may suggest a key role of this T-cell subset in the modulation of the abnormal immune response in SLE. Strategies aimed at expanding this Treg subset for therapeutic purpose deserve to be investigated.  相似文献   
83.
Bloom’s syndrome (BS) is a rare genetic disorder characterised by genomic instability and cancer susceptibility. BLM, the gene mutated in BS, encodes a member of the RecQ family of DNA helicases. Here, we identify hMLH1, which is involved in mismatch repair (MMR) and recombination, as a protein that directly interacts with BLM both in vivo and in vitro, and that the two proteins co-localise to discrete nuclear foci. The interaction between BLM and hMLH1 appears to have been evolutionarily conserved, as Sgs1p, the Saccharomyces cerevisiae homologue of BLM, interacts with yeast Mlh1p. However, cell extracts derived from BS patients show no obvious defects in MMR compared to wild-type- and BLM-complemented BS cell extracts. We conclude that the hMLH1–BLM interaction is not essential for post-replicative MMR, but, more likely, is required for some aspect of genetic recombination.  相似文献   
84.
Graziella Mura 《Hydrobiologia》2003,501(1-3):133-137
The morphology of the female ovisac of the fairy shrimp Artemiopsis stefanssoni Johansen, 1921, is analysed by SEM. SEM observations reveal the existence of a genital opening located ventrally, but anterior to the area where the genital pore is normally situated. Ornamented frontal knobs resembling those on the second antennae of males of Artemia were also found in Artemiopsismales, and account for its particular mating behaviour.  相似文献   
85.
The effects of ammonium and glutamine supply on amino acid levels and the activity of glucose-6P dehydrogenase (G6PDH EC 1.1.1.49), the main regulated enzyme of the oxidative pentose phosphate pathway, were investigated in barley roots ( Hordeum vulgare cv. Alfeo). Feeding ammonium to barley plants increased the contents of glutamine, asparagine and G6PDH in roots. These effects were abolished by using inhibitors of glutamine synthetase. Glutamine-fed barley roots showed a similar increase in G6PDH activities to ammonium-fed plants. Two G6PDH enzymes (G6PDH 1 and 2) were partially purified and characterized from ammonium-fed and glutamine-fed roots. The isozymes had different pH optima and apparent Km values for glucose-6P. G6PDH 2 showed similar kinetic parameters to the G6PDH present in root extracts of barley grown without any nitrogen source, while G6PDH 1 exhibited different kinetic parameters, suggesting the appearance of a second G6PDH isoform in response to ammonium. Western blot analysis demonstrated the existence of two G6PDH subunits of different molecular mass in barley roots grown in the presence of ammonium or glutamine, while only one isoform could be detected in roots grown without any nitrogen source. The results suggest a primary role of ammonium and/or glutamine in the appearance of a novel G6PDH isoform; this enzyme (G6PDH 1) shows kinetic parameters similar to those measured previously for chloroplastic and plastidic isoforms and seems to be induced by changes in glutamine content or a related compound(s) in the roots.  相似文献   
86.
87.

Background

Chronic cerebrospinal venous insufficiency (CCSVI) has been associated to multiple sclerosis (MS).

Objective

To evaluate the possible association between CCSVI and MS, using a population-based control design.

Methods

A random cohort of 148 incident MS patients were enrolled in the study. We have also studied 20 patients with clinically isolated syndrome (CIS), 40 patients with other neurological diseases (OND), and 172 healthy controls. Transcranial (TCC) and Echo Color Doppler (ECD) were carried out in 380 subjects. A subject was considered CCSVI positive if ≥2 venous hemodynamic criteria were fulfilled.

Results

CCSVI was present in 28 (18.9%) of the MS patients, in 2 (10%) of CIS patients, in 11 (6.4%) of the controls, and in 2 (5%) of the OND patients. A significant association between MS and CCSVI was found with an odds ratio of 3.41 (95% confidence interval 1.63–7.13; p = 0.001). CCSVI was significantly more frequent among MS subjects with a disease duration longer than 144 months (26.1% versus 12.6% of patients with duration shorter than 144 months; p = 0.03) and among patients with secondary progressive (SP) and primary progressive (PP) forms (30.2% and 29.4, respectively) than in patients with relapsing remitting (RR) MS (14.3%). A stronger association was found considering SP and PP forms (age adjusted OR = 4.7; 95% CI 1.83–12.0, p = 0.001); the association was weaker with the RR patients (age adjusted OR = 2.58; 95%CI 1.12–5.92; p = 0.02) or not significant in CIS group (age adjusted OR = 2.04; 95%CI 0.40–10.3; p = 0.4).

Conclusions

A higher frequency of CCSVI has been found in MS patients; it was more evident in patients with advanced MS, suggesting that CCSVI could be related to MS disability.  相似文献   
88.
The rhizobacterial strain X33d was previously shown to suppress the growth of the weed great brome (Bromus diandrus Roth.). The aim of this work was to identify X33d, characterize its physiological activities, assess its specificity on different non-target crops, and its impact on the growth and the root architecture of great brome and durum wheat (Triticum durum Desf.) grown alone and together. Based on 16S rDNA sequencing, X33d was identified as Pseudomonas trivialis. The specificity assay, performed on a mixture of soil/sand/peat, highlighted the suppressive activity of P. trivialis X33d against great brome and the promoting effect on most of the considered crops, especially durum wheat. Although the growth of durum wheat on quartz sand was unaffected, P. trivialis X33d suppressed the growth and affected the root architecture of great brome, especially when co-seeded with durum wheat. Great brome plants inoculated with X33d and co-seeded with durum wheat showed low root biomass, short root systems and low surface area, volume and number of tips. Moreover, P. trivialis X33d synthesized indole-acetic acid (IAA) that could be involved both in great brome growth suppression and durum wheat growth promotion. Our results indicate that P. trivialis X33d could be exploited as a potential biocontrol agent against great brome without affecting the durum wheat growth. These results are discussed in relation to the competitive capability of great brome towards durum wheat.  相似文献   
89.
90.
AIMS: Conflicting results exist regarding bone mineral density (BMD), metabolism and reproductive function of adult patients with congenital adrenal hyperplasia (CAH). We evaluated the long-term outcome and the impact of chronic glucocorticoid replacement in these patients. METHODS: Physical characteristics, serum hormone concentrations, BMD and metabolism were studied in 45 consecutive CAH adult patients. RESULTS: Among the 36 women, only 14 (39%) had regular menses. Among the 27 women with classical CAH, the mean number of surgical reconstructions of virilized genitalia was 2.1 +/- 0.2. Twenty of them (74%) were sexually active. Three men presented with testicular adrenal rest tumors. Twenty-five patients (55%) had decreased BMD at the femoral neck and/or at the lumbar spine. BMI was correlated with the BMD T-score at the femoral neck (p < 0.001) and at the lumbar spine (p < 0.01). Hydrocortisone dose was negatively correlated with the BMD T-score at the femoral neck (p = 0.04). Subjects with osteopenia had a significantly lower BMI and received higher hydrocortisone dose than those with normal BMD. Overweight was found in 21 patients (47%). There was a significantly positive correlation between HOMA and BMI (p < 0.001), and between HOMA and 17-OHP levels (p = 0.016). CONCLUSIONS: Adult patients with CAH treated with long-term glucocorticoids are at risk for decreased BMD, increased BMI, and disturbed reproductive function.  相似文献   
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