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991.
ABSTRACT: BACKGROUND: Vertebral fractures, the most common type of osteoporotic fractures, are associated with increased risk of subsequent fracture, morbidity, and mortality. The aim of this study was to examine the contribution of important risk factors to the variability in vertebral fracture risk. METHODS: Vertebral fracture was ascertained by VFA method (DXA, GE Lunar Prodigy) in 2887 men and women, aged between 38 and 87 years, in the population-based Tromso Study 2007/2008. Bone mineral density (BMD; g/cm2) at the hip was measured by DXA. Lifestyle information was collected by questionnaires. Multivariable logistic regression model, with anthropometric and lifestyle factors included, was used to assess the association between each or combined risk factors and vertebral fracture risk. Population attributable risk was estimated for combined risk factors in the final multivariable model. RESULTS: In both sexes, age (odds ratio [OR] per 5 year increase: 1.32; 95% CI 1.19-1.45 in women and 1.21; 95% CI 1.10-1.33 in men) and BMD (OR per SD decrease: 1.60; 95% CI 1.34-1.90 in women and1.40; 95% CI 1.18-1.67 in men) were independent risk factors for vertebral fracture. At BMD levels higher than 0.85 g/cm2, men had a greater risk of fracture than women (OR 1.52; 95% CI 1.14-2.04), after adjusting for age. In women and men, respectively, approximately 46% and 33% of vertebral fracture risk was attributable to advancing age (more than 70 years) and low BMD (less than 0.85 g/cm2), with the latter having a greater effect than the former. CONCLUSIONS: These data confirm that age and BMD are major risk factors for vertebral fracture risk. However, in both sexes the two factors accounted for less than half of fracture risk. The identification of individuals with vertebral fracture is still a challenge.  相似文献   
992.

Purpose

Recent reports discuss the altered bone homeostasis in cigarette smokers, being a risk factor for osteoporosis and negatively influencing fracture healing. Cigarette smoke is known to induce oxidative stress in the body via an increased production of reactive oxygen species (ROS). These increases in ROS are thought to damage the bone-forming osteoblasts. Naturally occurring polyphenols contained in green tea extract (GTE), e.g., catechins, are known to have anti-oxidative properties. Therefore, the aim of this study was to investigate whether GTE and especially catechins protect primary human osteoblasts from cigarette smoke-induced damage and to identify the underlying mechanisms.

Methods

Primary human osteoblasts were isolated from patients?? femur heads. Cigarette smoke medium (CSM) was obtained using a gas-washing bottle and standardized by its optical density (OD320) at ???=?320?nm. ROS formation was measured using 2??7??dichlorofluorescein diacetate, and osteoblasts?? viability was detected by resazurin conversion.

Results

Co-, pre-, and post-incubation with GTE and catechins significantly reduced ROS formation and thus improved the viability of CSM-treated osteoblasts. Besides GTE??s direct radical scavenging properties, pre-incubation with both GTE and catechins protected osteoblasts from CSM-induced damage. Inhibition of the anti-oxidative enzyme HO-1 significantly reduced the protective effect of GTE and catechins emphasizing the key role of this enzyme in GTE anti-oxidative effect.

Conclusions

Our data suggest possible beneficial effects on bone homeostasis, fracture healing, and bone mineral density following a GTE-rich diet or supplementation.  相似文献   
993.
Journal of Assisted Reproduction and Genetics - Excess embryos transferred (ET) (> plurality at birth) and fetal heartbeats (FHB) at 6 weeks’ gestation are associated with reductions...  相似文献   
994.
Food cravings have been understudied in bariatric surgery patients and the Food Craving Questionnaire-Trait has not been validated in this population. Reliability and validity of the FCQ-T were examined and a regression analysis was run to determine whether or not preoperative scores on individual subscales of the instrument could predict weight loss at 6 months. The FCQ-T demonstrated excellent internal consistency in bariatric surgery-seeking patients, and individual subscales measuring emotion and mood were correlated with other measures of depression and anxiety. Endorsement of binge eating or emotional eating behaviors during a clinical interview was correlated with similar subscales on the FCQ-T. Higher scores on the subscale ‘cues that may trigger food cravings’ were associated with greater weight loss at 6 months post-surgery and higher scores on the subscale ‘guilt from cravings and/or giving into them’ was associated with less weight loss. Management of external cues may predict successful outcomes while emotional impact of cravings may indicate the need for further intervention to help manage specific food craving traits.  相似文献   
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The functional consequence of long-term retinal detachment in the porcine model is examined by multifocal electroretinography (mfERG). Retinal detachment (RD) in humans leaves permanent visual impairment, despite anatomical successful reattachment surgery. To improve treatment, adjuvant pharmaceutical therapy is needed, and can only be tested in a suitable animal model. The porcine model is promising and the mfERG is well validated in this model. RD was induced in 18 pigs by vitrectomy and healon injection of various concentrations. Preoperatively and 6 weeks postoperatively eight animals were examined by mfERG. The major component P1 was analyzed statistically. Indirect ophthalmoscopy and bilateral color fundus photography (FP) were performed. Selected animals underwent high-resolution optical coherence tomography (OCT). Examination by ophthalmoscopy and FP showed that the RDs remained detached for the 6 weeks of follow-up. The P1 amplitude of the mfERG did not differ significantly between the detached areas, the surrounding attached areas, and the healthy eye (p = 0.25). Similarly, P1 implicit time did not differ between the areas (p = 0.85). The lack of functional consequences of long-term RD makes the porcine model unsuitable for examining adjuvant pharmaceutical RD treatment. Future studies should focus on foveated primates.  相似文献   
999.
In recent years the safety of the yellow fever live vaccine 17D came under scrutiny. The focus was on serious adverse events after vaccinations that resemble a wild type infection with yellow fever and whose reasons are still not known. Also the exact mechanism of attenuation of the vaccine remains unknown to this day. In this context, the standards of safety and surveillance in vaccine production and administration have been discussed. Therein embodied was the demand for improved documentation of the derivation of the seed virus used for yellow fever vaccine production. So far, there was just a historical genealogy available that is based on source area and passage level. However, there is a need for a documentation based on molecular information to get better insights into the mechanisms of pathology. In this work we sequenced the whole genome of different passages of the YFV-17D strain used by Crucell Switzerland AG for vaccine production. Using all other publically available 17D full genome sequences we compared the sequence variance of all vaccine strains and oppose a phylogenetic tree based on full genome sequences to the historical genealogy.  相似文献   
1000.
In a previous vaccine study, we reported significant and apparently sterilizing immunity to high-dose, mucosal, simian immunodeficiency virus (SIV) quasi-species challenge. The vaccine consisted of vectors based on vesicular stomatitis virus (VSV) expressing simian immunodeficiency virus (SIV) gag and env genes, a boost with propagating replicon particles expressing the same SIV genes, and a second boost with VSV-based vectors. Concurrent with that published study we had a parallel group of macaques given the same doses of vaccine vectors, but in addition, we included a third VSV vector expressing rhesus macaque GM-CSF in the priming immunization only. We report here that addition of the vector expressing GM-CSF did not enhance CD8 T cell or antibody responses to SIV antigens, and almost completely abolished the vaccine protection against high-dose mucosal challenge with SIV. Expression of GM-CSF may have limited vector replication excessively in the macaque model. Our results suggest caution in the use of GM-CSF as a vaccine adjuvant, especially when expressed by a viral vector. Combining vaccine group animals from this study and the previous study we found that there was a marginal but significant positive correlation between the neutralizing antibody to a neutralization resistant SIV Env and protection from infection.  相似文献   
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