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91.
Bulletin of Environmental Contamination and Toxicology - Although water pollution by metals in the Danube River is considered high, little is known about its impact on sturgeons. In this regard,...  相似文献   
92.

Objectives

The aims of this study in SLE population were (1) to describe ultrasonography (US) joint abnormalities, (2) to estimate the reliability of clinical swollen joint count (C-SJC) and SLEDAI (C-SLEDAI) versus US-SJC and US-SLEDAI scores, (3) to highlight specific patterns of lupus patients with Power Doppler (PD) abnormalities.

Method

For this cross-sectional multicenter study, 151 consecutive adult SLE patients were recruited. Evaluation included a clinical standardized joint assessment, B-mode and PD US of 40 joints and 26 tendons blinded for clinical examination. Reliability and agreement between clinical and B-mode US were calculated using the intraclass correlation coefficients (ICC [95% Confidence Interval]).

Results

We found a very high frequency of subclinical US abnormalities in asymptomatic patients: 85% of patients without joint symptoms had at least 1 US abnormality. Among them 46 patients (87%) had a history of joint involvement. The most frequent abnormalities were joint effusmaions (108 patients), synovial hypertrophy (SH, 109 patients) and synovitis (61 patients). Joint or tendon PD signal (grade > 1) was found in 44% of patients (67/151). Synovitis were mainly located especially on MCPs and wrists. Even if reliability between clinical and grey-scale US SJC assessments was poor, reliability between clinical and US SLEDAI was good. Comparison between SLE patients with and without PD signal did not show any specific SLE pattern.

Conclusion

US may be useful to assess joint involvement in SLE patients but did not significantly change SLEDAI score.  相似文献   
93.
IFN-γ is a critical mediator of host defense against Mycobacterium tuberculosis (Mtb) infection. Antigen-specific CD4+ T cells have long been regarded as the main producer of IFN-γ in tuberculosis (TB), and CD4+ T cell immunity is the main target of current TB vaccine candidates. However, given the recent failures of such a TB vaccine candidate in clinical trials, strategies to harness CD4-independent mechanisms of protection should be included in future vaccine design. Here, we have reported that noncognate IFN-γ production by Mtb antigen–independent memory CD8+ T cells and NK cells is protective during Mtb infection and evaluated the mechanistic regulation of IFN-γ production by these cells in vivo. Transfer of arenavirus- or protein-specific CD8+ T cells or NK cells reduced the mortality and morbidity rates of mice highly susceptible to TB in an IFN-γ–dependent manner. Secretion of IFN-γ by these cell populations required IL-18, sensing of mycobacterial viability, Mtb protein 6-kDa early secretory antigenic target–mediated (ESAT-6–mediated) cytosolic contact, and activation of NLR family pyrin domain–containing protein 3 (NLRP3) inflammasomes in CD11c+ cell subsets. Neutralization of IL-18 abrogated protection in susceptible recipient mice that had received noncognate cells. Moreover, improved Mycobacterium bovis bacillus Calmette-Guérin (BCG) vaccine–induced protection was lost in the absence of ESAT-6–dependent cytosolic contact. Our findings provide a comprehensive mechanistic framework for antigen-independent IFN-γ secretion in response to Mtb with critical implications for future intervention strategies against TB.  相似文献   
94.
Objective: We aimed to investigate the effects of thyroid hormone withdrawal on N-terminal prohormone forms of atrial natriuretic peptide (NT-proANP) and brain natriuretic peptide (NT-proBNP) during radioiodine therapy in female patients with differentiated thyroid cancer (DTC).

Methods: Serum concentrations of thyroid-stimulating hormone (TSH), free triiodothyronine (FT3), NT-proANP and NT-proBNP were measured in 51 female patients with DTC (48.7?±?4.2 years) at three time-points: day of radioiodine therapy (t1 – under acute hypothyroidism), 5 days after radioiodine (t2 – under acute hypothyroidism) and 3 months after radioiodine (t3 – under TSH suppression). Thirty healthy euthyroid women served as controls (42.8?±?5.6 years).

Results: At t1/t2/t3, median NT-proANP was 5.2/1.7/487?pmol/L vs. 297.7?pmol/L in control group (p?p?p?r?=?0.38, p?=?0.005), NT-proANP/NT-proBNP ratios (r?=?0.47, p?=?0.001), heart rate (r?=?0.39, p?=?0.005), and negatively with mean arterial blood pressure (r?=??0.58, p?Conclusions: Our results indicate that NT-proANP reflects more accurately direct thyroid hormone effects than NT-proBNP. Thyroid hormone-dependent hemodynamic effects seem to be overlapped on the direct stimulatory effect of thyroid hormones on NT-proANP secretion by cardiac myocytes.  相似文献   
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Contemplation of non-genetic risk factors that are influencing the onset and development of diabetic nephropathy (diabetic kidney disease--DKD) is very important. This article is integrative, assessing the existent data about several possible risk factors for DKD. Because the age of onset and postpubertal duration of diabetes seems to be strongly correlated with DKD, it is feasible for puberty to be another independent risk factor. Data analysis regarding puberty and possible explanatory mechanisms to link it with DKD, as the connection with DKD of other situations, with special hormonal status (like pregnancy), is also part of this article. Summing up the data about hormonal status, we can conclude that ANF levels are a risk factor for diabetic nephropathy because they are implicated in diminution of urinary Na elimination and hypertension and subsequent urinary albumin excretion (UAE) in case of inadequate glycaemic control. The evidences regarding GH are indicating that it is a risk factor for DKD and that he is probably implicated in glomerular hypertrophy onset at puberty. The urinary elimination levels of GH are very strong correlated with UAE being putative early marker for DKD. Also the GH deficiency seems to be a protective mechanism for DKD apparition. GH is strongly correlated with IGF-1 that has very high urinary levels in microalbuminuric patients. These levels are very well related to UAE, kidney volume--important markers for glomerular hypertrophy. The evidences accumulated until now regarding the role of masculine gender, testosterone and estrogens in DKD are inarticulate.  相似文献   
100.
Liposomes entrapment in different forms of polymers represents in the last few years a method to modify the drug release kinetics in order to attend the specificity of this phenomenon. This will result generally in complex systems in which liposomes are dispersed in polymer matrices like gels, hydrogels and microparticles. As a consequence the drug release will be influenced by both polymer matrix and small carrier entrapped in. The researchers are trying to control the release of drug from such solid complex system by modulating not only the vesicle properties but also those of polymer support. This kind of system is necessary also for the cases when time stable liposomes are desired, being already well known that the major drawback of this type of carrier is the stability in time and in different physiologic conditions.  相似文献   
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