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Angiogenesis, i.e. the development and growth of blood vessels, is a major topic of research as it plays an important role in normal development and in various pathologies. Recent evidence revealed the existence of different mechanisms of blood vessel growth, including sprouting and intussusceptive angiogenesis, vascular mimicry, and blood vessel cooption. The latter two have only been observed in tumor growth, but sprouting and intussusceptive angiogenesis also occur in healthy, physiologically growing tissues. Despite this variety of angiogenic mechanisms, most of the current research is focused on the mechanism of sprouting angiogenesis because this mechanism was first described and because most existing experimental models are related to sprouting angiogenesis. Consequently, the mechanism of intussusceptive angiogenesis is often overlooked in angiogenesis research. Here, the mechanism of intussusceptive angiogenesis is reviewed and the current techniques and models for investigating intussusceptive angiogenesis are summarized. In addition, other mechanisms of vascular growth are briefly reviewed.  相似文献   
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The functional imaging technique of 18F‐fluoride positron emission tomography (18F‐PET) allows the noninvasive quantitative assessment of regional bone formation at any skeletal site, including the spine and hip. The aim of this study was to determine if 18F‐PET can be used as an early biomarker of treatment efficacy at the hip. Twenty‐seven treatment‐naive postmenopausal women with osteopenia were randomized to receive teriparatide and calcium and vitamin D (TPT group, n = 13) or calcium and vitamin D only (control group, n = 14). Subjects in the TPT group were treated with 20 µg/day teriparatide for 12 weeks. 18F‐PET scans of the proximal femur, pelvis, and lumbar spine were performed at baseline and 12 weeks. The plasma clearance of 18F‐fluoride to bone, Ki, a validated measurement of bone formation, was measured at four regions of the hip, lumbar spine, and pelvis. A significant increase in Ki was observed at all regions of interest (ROIs), including the total hip (+27%, p = 0.002), femoral neck (+25%, p = 0.040), hip trabecular ROI (+21%, p = 0.017), and hip cortical ROI (+51%, p = 0.001) in the TPT group. Significant increases in Ki in response to TPT were also observed at the lumbar spine (+18%, p = 0.001) and pelvis (+42%, p = 0.001). No significant changes in Ki were observed for the control group. Changes in BMD and bone turnover markers were consistent with previous trials of teriparatide. In conclusion, this is the first study to our knowledge to demonstrate that 18F‐PET can be used as an imaging biomarker for determining treatment efficacy at the hip as early as 12 weeks after initiation of therapy.  相似文献   
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Minor physical anomalies (MPAs) are slight structural aberrations indicative of abnormal neurodevelopment. Most studies of MPAs in bipolar disorder have yielded limited results. We attempted to assess the potential value of MPAs as a classifying test in the status bipolar I patients vs. normal controls. Sixty one bipolar I patients and 103 controls were evaluated for MPAs using a slightly modified version of the Waldrop scale. The specificity, sensitivity and predictive value of different total MPA (MPA-T) scores were determined. The cut-off MPA-T scores that optimally discriminated patients from controls (exhibiting the most balanced sets of sensitivity, specificity, positive and negative predictive values) were MPA-T≥4 and MPA-T≥5. These values set a “border zone” in which bipolar I patients began to prevail significantly over controls. The latter presented most frequently with MPA-T ≤3 and rarely with MPA-T ≥6. Bipolar I patients prevailed among outliers (subjects with significantly higher MPA-T scores). Our data establish MPA-T score as a reliable index in distinguishing between bipolar I patients and normal controls and are consistent with the hypothesis of abnormal neurodevelopment in bipolar disorder.  相似文献   
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The prevalence of psychiatric conditions among elite athletes is still under debate. More and more evidence has accumulated that high-performance athletes are not protected from mental disorders as previously thought. The authors discuss the issue of the sport specificity of selected mental diseases in elite athletes. Specific aspects of eating disorders, exercise addiction, chronic traumatic encephalopathy and mood disorders in the context of overtraining syndrome are examined. In particular, the interrelationship between life and work characteristics unique to elite athletes and the development of mental disorders are reviewed. Differences of clinical presentation and some therapeutic consequences are discussed. The authors suggest that the physical and mental strains endured by elite athletes might influence the onset and severity of their psychiatric disorder. Beside the existing research strategies dealing with the amount of exercise, its intensity and lack of recreation experienced by athletes, further research on psycho-social factors is needed to better understand the sport-specific aetiology of mental disorders in high-performance athletes.

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