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91.
Genetic factors that predispose individuals to Behcet’s disease (BD) are considered to play an important role in the development of the disease. The serum level of tumor necrosis factor (TNF) is elevated in patients with BD, and a dramatic response to anti-TNF-α antibody treatment further supports the role of TNF in BD. We investigated the distribution of TNF-α promoter −1031T/C and −308G/A polymorphisms in 53 BD patients of Iranian Azeri Turks and 79 matched healthy controls, via the PCR–RFLP technique. The frequency of the TNF-α −1031C allele was significantly higher in Behcet’s patients than in healthy controls (p < 0.0001, OR = 3.08; 95% CI = 1.73–5.47), whereas the frequency of the TNF-α −308A allele was similar in the two compared groups. The frequency of CG haplotype was significantly higher (p < 0.0001, OR = 3.42; 95% CI = 1.89–6.18), and that of the TA haplotype was significantly lower in BD patients than in healthy controls. These results suggest that TNF-α is a susceptibility gene for BD in patients from Iranian Azeri Turk ethnic group.  相似文献   
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Background

Phase contrast velocimetry cardiovascular magnetic resonance (PC-CMR) is a powerful and versatile tool allowing assessment of in vivo motion of the myocardium. However, PC-CMR is sensitive to motion related artifacts causing errors that are geometrically systematic, rendering regional analysis of myocardial function challenging. The objective of this study was to establish an optimized PC-CMR method able to provide novel insight in the complex regional motion and strain of the rodent myocardium, and provide a proof-of-concept in normal and diseased rat hearts with higher temporal and spatial resolution than previously reported.

Methods

A PC-CMR protocol optimized for assessing the motion and deformation of the myocardium in rats with high spatiotemporal resolution was established, and ten animals with different degree of cardiac dysfunction underwent examination and served as proof-of-concept. Global and regional myocardial velocities and circumferential strain were calculated, and the results were compared to five control animals. Furthermore, the global strain measurements were validated against speckle-tracking echocardiography, and inter- and intrastudy variability of the protocol were evaluated.

Results

The presented method allows assessment of regional myocardial function in rats with high level of detail; temporal resolution was 3.2 ms, and analysis was done using 32 circumferential segments. In the dysfunctional hearts, global and regional function were distinctly altered, including reduced global peak values, increased regional heterogeneity and increased index of dyssynchrony. Strain derived from the PC-CMR data was in excellent agreement with echocardiography (r = 0.95, p < 0.001; limits-of-agreement −0.02 ± 3.92%strain), and intra- and interstudy variability were low for both velocity and strain (limits-of-agreement, radial motion: 0.01 ± 0.32 cm/s and −0.06 ± 0.75 cm/s; circumferential strain: -0.16 ± 0.89%strain and −0.71 ± 1.67%strain, for intra- and interstudy, respectively).

Conclusion

We demonstrate, for the first time, that PC-CMR enables high-resolution evaluation of in vivo circumferential strain in addition to myocardial motion of the rat heart. In combination with the superior geometric robustness of CMR, this ultimately provides a tool for longitudinal studies of regional function in rodents with high level of detail.  相似文献   
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Objectives: Rheumatoid arthritis (RA) is an autoimmune disease characterized by an increase in some autoantibodies and proteolytic enzymes, leading to joint destruction. Although recent investigations have considered vitamin K as an anti-inflammatory nutrient with an important role in bone metabolism, there is currently limited information on its efficacy in RA. We aimed to examine the effects of vitamin K1 (phylloquinone) on the biomarker of joint destruction and autoantibody in patients with RA.

Materials and Methods: This was a randomized clinical trial in which 64 women with RA who fulfilled the eligibility criteria were randomly allocated to an intervention or a control group. Vitamin K1 or placebo was administered to the participants for 8 weeks. Baseline characteristics and anthropometric measures were obtained. Clinical status using disease activity score in 28 joints (DAS-28), serum levels of matrix metalloproteinase-3 (MMP-3), and rheumatoid factor (RF) were assessed before and after the intervention.

Results: The serum level of MMP-3 compared with the baseline values did not change significantly in the groups. However, the serum concentration of RF decreased significantly in the vitamin K1 group (p = 0.041). Intergroup comparison showed no significant change in RF serum level after adjusting for relevant confounders (p > 0.05).

Conclusions: Vitamin K1 supplementation at 10 mg/day for 8 weeks did not alter joint destruction and immune status in the patients with RA compared with the controls.  相似文献   

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Objective: Considering the importance of inflammation in the pathogenesis of osteoarthritis (OA) and induction of pain, this study was aimed to investigate the effect of L-carnitine supplementation on serum inflammatory mediators and OA-associated pain in females with knee OA.

Methods: In this clinical trial, 72 females with mild to moderate knee osteoarthritis started the study, divided into 2 groups to receive 750 mg/day L-carnitine (n = 36) or placebo (n = 36) for 8 weeks. Serum levels of Interleukine-1β (IL-1β), high-sensitivity C-reactive protein (hs-CRP), matrix metalloproteinases (MMPs)-1 and -13, and visual analog scale (VAS) for pain were assessed before and after supplementation. Data were analyzed by t test, Wilcoxon signed rank test, Mann-Whitney U test, and analysis of covariance.

Results: Only 69 patients (33 in the L-carnitine group and 36 in the placebo group) completed the study. L-Carnitine supplementation decreased serum IL-1β and MMP-1 levels significantly (p = 0.001 and p = 0.021, respectively); however, serum hs-CRP and MMP-13 levels did not change significantly (p > 0.05). In the placebo group, serum IL-1β levels increased significantly (p = 0.011), whereas other studied biomarkers did not change significantly. The mean VAS score decreased significantly in the L-carnitine and placebo groups by 52.67% and 21.82%, respectively (p < 0.001). Significant differences were only observed between the 2 groups in serum IL-1β (p < 0.001) and MMP-1 (p = 0.006) levels and mean VAS score (p = 0.002) after adjusting for baseline values and covariates.

Conclusion: Despite observed beneficial effects of short-term supplementation of L-carnitine in decreasing serum inflammatory mediators and improving pain in knee OA patients, further studies are needed to achieve concise conclusions.  相似文献   

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Objectives

The aim of the study was to determine whether behaviourally informed short message service (SMS) primer and reminder messages could increase the return rate of HIV self‐sampling kits ordered online.

Methods

The study was a 2 × 2 factorial design randomized control trial. A total of 9585 individuals who ordered a self‐sampling kit from www.freetesting.hiv different SMS combinations: 1) standard reminders sent days 3 and 7 after dispatch (control); 2) primer sent 1 day after dispatch plus standard reminders; 3) behavioural insights (BI) reminders (no primer); or 4) primer plus BI reminders. The analysis was restricted to individuals who received all messages (n = 8999). We used logistic regression to investigate independent effects of the primer and BI reminders and their interaction. We explored the impact of sociodemographic characteristics on kit return as a secondary analysis.

Results

Those who received the primer and BI reminders had a return rate 4% higher than that of those who received the standard messages. We found strong evidence of a positive effect of the BI reminders (odds ratio 1.13; 95% confidence interval 1.04–1.23; P = 0.003) but no evidence for an effect of the primer, or for an interaction between the two interventions. Odds of kit return increased with age, with those aged ≥ 65 years being almost 2.5 times more likely to return the kit than those aged 25–34 years. Men who have sex with men were 1.5–4.5 times more likely to return the kit compared with other sexual behaviour and gender identity groups. Non‐African black clients were 25% less likely to return the kit compared with other ethnicities.

Conclusions

Adding BI to reminder messages was successful in improving return rates at no additional cost.  相似文献   
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