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51.
Kinins exert cardioprotective effects via 2 G-protein-coupled receptors, B1 and B2. Using B1 kinin receptor gene knockout mice (B1-/-), we tested the hypotheses that the B1 receptor plays an important role in preservation of cardiac function, whereas lack of B1 may accelerate cardiac remodeling and dysfunction after myocardial infarction, and that B2 receptors may compensate for lack of B1, whereas blockade of B2 receptors in B1-/- mice may cause further deterioration of cardiac function and remodeling. Female B1-/- mice and wild-type controls (C57BL/6J, B1+/+) underwent sham surgery or myocardial infarction and were treated with either vehicle or B2-antagonist (icatibant, 500 microg/kg per day, subcutaneous) for 8 weeks. We found that in sham myocardial infarction, B1-/- mice had a larger left ventricular diastolic chamber dimension both initially and at 4 to 8 weeks compared with B1+/+. Left ventricular mass and myocyte size were also larger in B1-/- with sham operation than in B1+/+, although cardiac function did not differ between strains. After myocardial infarction, cardiac remodeling and function were similar in both strains, although B1-/- mice tended to have lower blood pressure. Blockade of B2 receptors tended to worsen cardiac remodeling and dysfunction in B1-/- but not in B1+/+. These results may suggest that B2 receptors play an important role in compensating for lack of B1 receptors in mice with myocardial infarction. Dual blockade of both B1 and B2 eliminates this compensation, leading to further deterioration of cardiac dysfunction and remodeling after myocardial infarction.  相似文献   
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Azole antifungal drug resistance in Aspergillus fumigatus is an emerging problem in several parts of the world. Here we investigated the distribution of such strains in soils from Germany. At a general positivity rate of 12%, most prevalently, we found strains with the TR34/L98H and TR46/Y121F/T289A alleles, dispersed along a corridor across northern Germany. Comparison of the distributions of resistance alleles and genotypes between environment and clinical samples suggests the presence of local clinical clusters.  相似文献   
53.
Currently, pressure ulcer preventive strategies focus mainly on pressure redistribution. Little attention is paid to reduce the harmful effects of shear‐force, because little is known about pathophysiological aspects of shear‐force. Even today, no method to measure the effects of shear‐force on the skin is available. Therefore, the aim of this study was to investigate the response to shear‐forces in terms of analyzing a noninvasive biomarker and reactive hyperemic parameter measured at the skin of healthy participants. A physical model was developed to produce a combination of pressure and shear or pressure alone on the skin. Ten healthy male participants were included and pressure (3.9 kPa) and a combined loading of pressure and shear (2.4 kPa + 14.5 N) was applied at the volar aspect of the forearms for 15 and 30 minutes. A Sebutape sample was used to collect IL‐1α and total protein (TP) noninvasively. The reactive hyperemic parameter was derived from a laser Doppler flowmeter. The increase in IL‐1α/TP‐ratio after a combined loading of pressure and shear for 30 minutes of 6.2 ± 2.5 was significantly higher compared with all other test conditions (p < 0.05). The increase in cutaneous blood cell flux was already significantly higher when a combined loading of pressure and shear was applied for 15 minutes compared with pressure alone. These results shows that the IL‐1α/TP‐ratio and cutaneous blood cell flux can be used as robust measures of the effect of shear‐force on skin in humans. Therefore, this model can be used to evaluate materials aimed at the reduction of shear.  相似文献   
54.
The expression of interferon inducible genes are reported to be heightened in systemic lupus erythematosus (SLE); nevertheless, not much is known regarding the genetic variants underlying these genes and their role in the pathogenesis of disease. Herein, we aim to explore the potential association and contribution of polymorphisms in MX1 gene (i) promoter with part of exon 1 (ii) intron 6, and (iii) their resulting haplotypes, with susceptibility to SLE. A total of 306 subjects, 152 SLE and 154 healthy controls (HC), were screened by direct sequencing method. Statistical analysis was carried out using appropriate software. The screening region of interest in MX1 revealed the existence of promoter (?123C/A, ?88G/T, ?20 A/C) and intron 6 (+9862G/A, +10190G/A, +9901C/G, +9920C/A, +9959C/T, +10047A/G) variants in SLE and HC. A significant association was observed between MX1 ?88G/T SNP and susceptibility to SLE (χ 2?=?4.18, p?=?0.04, OR?=?1.89, 95 % CI 1.03–3.5). Haplotype analysis also revealed increased risk of SLE among individuals carrying CTA haplotype (?123 C, ?88 T, ?20 A) (χ 2?=?5.74, p?=?0.017, OR?=?4.28, 95 % CI 1.30–14.06). None of the other tested variants showed any significant association with SLE. The present study is the first to reveal the influence of genetic variation in MX1 gene in susceptibility to SLE.  相似文献   
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Objective

This paper uses baseline data from a randomized clinical trial to evaluate cross-sectional indicators of root caries in caries-active adults.

Materials and methods

Adults (21–80?years) having at least 12 erupted teeth and between one and ten caries lesions were enrolled. Participants (n?=?437) received caries exams by trained, calibrated examiners and responded to baseline demographic and medical–dental questionnaires. We examined associations between baseline characteristics and (1) the presence of any root caries using Mantel–Haenszel hypothesis tests and odds ratio (OR) estimators and (2) the number of root surfaces with caries among study participants with exposed root surfaces (n?=?349) using Mantel–Haenszel mean score tests and Mann–Whitney estimators.

Results/conclusions

Adjusting for study site and age, male gender [OR, 1.72; 95% confidence interval (CI), 1.08, 2.78], white race (OR, 2.39; 95% CI, 1.43, 3.98), recent dental visit (OR, 1.98; 95% CI, 1.07, 3.66), poor self-described oral health (OR, 2.65; 95% CI, 1.10, 6.39), and recent professional fluoride treatment (OR, 1.85; 95% CI, 1.06, 3.25) were significantly associated with increased odds to have any root caries, and study participants with exposed root surfaces characterized by male gender [Mann–Whitney probability estimate (MW)?=?0.57; 95% CI, 0.51, 0.63), white race (MW, 0.61; 0.55, 0.68), recent dental visit (MW, 0.58; 0.50, 0.67), poor self-described oral health (MW, 0.61; 0.53, 0.69), and flossing at least once per day (MW, 0.57; 95% CI, 0.51, 0.62) were significantly more likely to have a greater number of root surfaces with caries than a randomly selected study participant from their respective complementary subgroups (female gender, non-white, etc.).

Clinical relevance

Our findings may help identify individuals at higher root caries risk.  相似文献   
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