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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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Cavernous haemangioma (cavernoma) is a benign vascular lesion, exceptionally located in cauda equina. We report a case, diagnosed and operated in the Department of Neurosurgery from Pitesti County Emergency Hospital, of a 60-year-old woman with history of lumbar region distress, who presented with low back pain, paravertebral muscle contracture, and bilateral lumbar radiculopathy, with sudden onset after lifting effort. The preoperative diagnosis was done using computed tomography (CT) and magnetic resonance imaging (MRI), and the patient underwent surgery—two level laminectomy, dural incision, and tumor dissection from the cauda equina nerve roots under operatory microscope. Histopathological examination confirmed the positive diagnosis of cavernoma of cauda equina. The patient''s outcome was favorable, without postoperative neurological deficits.  相似文献   
105.
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   
108.

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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We present a case report on visual brain plasticity after total blindness acquired in adulthood. SH lost her sight when she was 27. Despite having been totally blind for 43 years, she reported to strongly rely on her vivid visual imagery. Three-Tesla magnetic resonance imaging (MRI) of SH and age-matched controls was performed. The MRI sequence included anatomical MRI, resting-state functional MRI, and task-related functional MRI where SH was instructed to imagine colours, faces, and motion. Compared to controls, voxel-based analysis revealed white matter loss along SH’s visual pathway as well as grey matter atrophy in the calcarine sulci. Yet we demonstrated activation in visual areas, including V1, using functional MRI. Of the four identified visual resting-state networks, none showed alterations in spatial extent; hence, SH’s preserved visual imagery seems to be mediated by intrinsic brain networks of normal extent. Time courses of two of these networks showed increased correlation with that of the inferior posterior default mode network, which may reflect adaptive changes supporting SH’s strong internal visual representations. Overall, our findings demonstrate that conscious visual experience is possible even after years of absence of extrinsic input.  相似文献   
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