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The study aimed to investigate the effects of n-butyrate and propionate on the proliferation and viability of human endothelial cells in culture. Proliferation was assessed by a 24-hour bromodeoxyuridine pulse labelling and immunoperoxidase method and viability was assessed by a colorimetric viability (MTT) assay. Endothelial cells were isolated from human umbilical vein by collagenase digestion. Experiments were performed on 96-well plates and cultures were exposed to different concentrations of n-butyrate and propionate for 2 days. n-butyrate and propionate caused significant reductions in the proliferation of endothelial cells at concentrations of 1.25 mM and 10 mM respectively (p less than 0.05); the reduction in proliferation was dose-dependent for both agents. n-butyrate was a more potent inhibitor of proliferation than propionate. However, there were no significant effects on the viability of the cells with both agents up to the highest concentrations tested (25 mM). The data indicate that n-butyrate and propionate inhibit endothelial cell proliferation which may contribute to the pathogenic effects of dental plaque in periodontal disease.  相似文献   
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7-dehydrocholesterol reductase (7-Dhcr) catalyses the final step in the pathway of cholesterol biosynthesis. Human patients with inborn errors of 7-Dhcr (Smith-Lemli-Opitz-Syndrome) have elevated serum levels of 7-dehydrocholesterol but low levels of cholesterol, which in phenotypical terms can result in growth retardation, craniofacial abnormalities including cleft palate, and reduced metal abilities. This study reports the isolation and molecular characterisation of 7-dehydrocholesterol reductase (Xdhcr7) from Xenopus laevis. During early embryonic development, the expression of Xdhcr7 is first of all spatially restricted to the Spemann's organizer and later to the notochord. In both tissues, Xdhcr7 is coexpressed with Sonic hedgehog (Shh), which itself is cholesterol-modified during autoproteolytic cleavage. Data from Xdhcr7 overexpression and knockdown experiments reveals that a tight control of cholesterol synthesis is particularly important for proper development of the central and peripheral nervous system.  相似文献   
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Patients who underwent isolated aortic valve replacement could come to attention for new onset aortic disease or progression of borderline alterations not corrected at the first operation, especially in the subset of bicuspid valve disease. We describe our technique in redo operations for aortic root disease, using only a vascular graft and sparing the previously implanted valve prosthesis. In case of normally functioning mechanical prosthesis, we always left the valve in situ and substituted the aortic root with a Dacron conduit, extending the replacement if necessary to the other diseased portions of the thoracic aorta.  相似文献   
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Propriospinal myoclonus (PSM) is a rare movement disorder characterized by involuntary spinal-generated muscular jerks that spread rostrally and caudally to other spinally innervated muscles. Most patients have no clear etiology, and conventional MRI of the spinal cord is generally normal. Here we report the use of magnetic resonance diffusion tensor imaging (DTI) and fiber tracking to detect tract-specific abnormalities in a patient with propriospinal myoclonus. As the patient had the fragile-X premutation and antithyroid antibodies, spinal cord DTI abnormalities may be related to these conditions. Tract-specific analysis may provide new insights into the pathophysiology of propriospinal myoclonus.  相似文献   
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We describe the first case of orofacial abnormal movements induced by adrafinil, a vigilance promoting agent of the same pharmacological class as modafinil. The dyskinesias did not spontaneously recover despite adrafinil withdrawal for a 4-month period. They were secondly dramatically improved by tetrabenazine, a presynaptic dopaminergic depleting drug which was introduced after the 4-month adrafinil-free period.  相似文献   
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OBJECTIVE: To investigate the increased incidence of papillary thyroid cancer as found in specimens of total thyroidectomies and potential correlation with etiological factors. STUDY DESIGN AND SETTING: A retrospective study on patients who underwent total thyroidectomy, from 1990 to 2004, in an academic tertiary referral medical center. Patients' records were placed in a database, which included medical condition, history, and demographics. Histopathological slides were reviewed with special focus on papillary cancer. RESULTS: Our series consisted of 2379 patients. Thyroid cancer was confirmed in 354 patients (14.88%). Papillary carcinoma represented the most frequent type (316 patients, 89.26%). Increased incidence of papillary carcinomas was noticed after 1995, reaching the maximum value in the year 2000. After 2000, there was a descending trend and then a plateau. CONCLUSION: The increased incidence of papillary thyroid cannot be attributed to dietary patterns or increased diagnostic and therapeutic activity. It is likely to be associated with increased radiation and may be associated with the Chernobyl fallout.  相似文献   
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