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Bone mineral density (BMD) is a highly heritable predictor of osteoporotic fracture. GWAS have identified hundreds of loci influencing BMD, but few have been functionally analyzed. In this study, we show that SNPs within a BMD locus on chromosome 14q32.32 alter splicing and expression of PAR-1a/microtubule affinity regulating kinase 3 (MARK3), a conserved serine/threonine kinase known to regulate bioenergetics, cell division, and polarity. Mice lacking Mark3 either globally or selectively in osteoblasts have increased bone mass at maturity. RNA profiling from Mark3-deficient osteoblasts suggested changes in the expression of components of the Notch signaling pathway. Mark3-deficient osteoblasts exhibited greater matrix mineralization compared with controls that was accompanied by reduced Jag1/Hes1 expression and diminished downstream JNK signaling. Overexpression of Jag1 in Mark3-deficient osteoblasts both in vitro and in vivo normalized mineralization capacity and bone mass, respectively. Together, these findings reveal a mechanism whereby genetically regulated alterations in Mark3 expression perturb cell signaling in osteoblasts to influence bone mass.  相似文献   
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Purpose

The development of Laparoscopic Linear Endostaplers (LLES) is crucial in minimally invasive approaches in bariatric surgery, but there have been very few published studies comparing 6-row LLES in Laparoscopic Sleeve Gastrectomy (LSG). The objective of this study was to compare two 6-row LLES in LSG.

Methods

A total of 60 patients were prospectively randomized to undergo LSG with either Medtronic Endo GIA? Tri-Staple technology (MTS) or AEON ? Endostapler(Lexington Medical) LLES. The measured parameters included patient demographics, comorbidity indices, LLES and specimen characteristics, postoperative symptoms, hospital stay, and total adverse events (AEs). Intraoperative bleeding was evaluated using five laparoscopic and corresponding endoscopic images of staple line before clip application, compared with a 1–5 Visual Analogue Scale (VAS), assessed by an independent bariatric surgeon who was blinded to the LLES used. Images of all cases were reviewed on the same day to increase test–retest reliability.

Results

Both groups were similar in patient demographics. Compared to MTS, AEON LLES group had significantly lower bleeding VAS scores in 4/5 laparoscopic images (pre-pyloric: 1.7?±?0.7 vs. 2.36?±?0.76, p?=?0.0007, mid-sleeve: 1.46?±?0.62 vs. 1.86?±?0.68, p?=?0.019, proximal sleeve: 1.6?±?0.77 vs. 2.0?±?0.83, p?=?0.038, gastro-esophageal junction: 1.43?±?0.67 vs. 1.86?±?0.77, p?=?0.014) and 3/5 endoscopic images (pre-pyloric: 1.56?±?0.56 vs. 2.36?±?0.76, p?=?0.006, incisura: 1.66?±?0.54 vs. 2.0?±?0.52, p?=?0.021, mid-sleeve: 1.63?±?0.49 vs. 2.0?±?0.45, p?=?0.005). There was no statistical difference in other parameters.

Conclusion

Both devices were equally safe and effective in terms of LLES and specimen characteristics, patient symptoms, hospital stay, and AEs. Bleeding VAS scores were significantly lower, favoring the AEON LLES.

Graphical abstract
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BACKGROUND: Obsessive-compulsive disorder (OCD) is a chronic, impairing and often comorbid disorder. METHODS: 1000 subjects who called the Anxiety Disorders Association of America (ADAA) were surveyed and divided in three groups: (a) callers with OCD (OCD) and two overlapping control groups: (b) callers with no axis I disorder (NAC) and (c) with no-OCD (NOC) using a 97-item questionnaire. RESULTS: The rate of OCD was 14.5% (N = 145). Relative to the NOC group, OCD subjects were more likely to be female, White, younger and not married. Relative to the NAC group, subjects with OCD were more likely to be White, not married and younger. OCD was accompanied by significant comorbidity and was associated with an increased number of visits to health professionals than NAC subjects. There was no significant difference regarding unemployment rates among the three groups. However, OCD callers were more likely than both control groups to have missed work or have decreased productivity due to their mental condition. OCD subjects took an average of 1 psychotropic medication in the past year and were statistically more likely than the control groups to experience sleepiness and nervousness as side effects. CONCLUSIONS: OCD was fairly prevalent among ADAA callers and presented high levels of comorbidity, impairment, health care utilization and sensitivity to psychotropic side effects.  相似文献   
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