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OBJECTIVE: Prosthetic treatment for speech disorders attributable to surgically acquired soft palate defects are introduced. CASE: A patient who underwent soft palate resection for cancer is presented. The resected portion of the soft palate was confined to the posterior segments. A prosthesis with a speech bulb was adapted to the patient. CONCLUSION: Excellent restoration of speech and improvement of velopharyngeal function was achieved following placement of the special prosthesis. 相似文献
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Feza Karakayali Nihan Haberal Hale Tufan Nesrin Hasirci Ozgur Basaran Sinasi Sevmis Aydin Akdur Aysel Kiziltay Mehmet Haberal 《Journal of investigative surgery》2007,20(3):167-173
Tranilast is an antiallergic drug that interferes with proliferation and migration of vascular smooth muscle cell induced by platelet-derived growth factor (PDGF) and transforming growth factor-beta1 (TGF-beta1). We investigated the local effect of tranilast on neointimal hyperplasia using tranilast-coated prosthetic grafts. The inner sides of the thin-walled polytetrafluoroethylene (PTFE) grafts were coated with chitosan and tranilast containing chitosan solution. Wistar albino rats (32) were used in the study. Patches (1 x 2 mm) for vascular grafts were prepared. Three groups were tested: group 1 (n = 12; tranilast coated), group 2 (n = 10; adhesive-only film-layer-coated), and group 3 (n = 10; normal ePTFE patch grafts sutured to the carotid arteries of the rats). Recipient sites of the carotid arteries were excised 4 weeks after surgery. All sections were examined histologically for graft patency, thrombus formation, and neointimal thickness. Expression of PDGF, fibroblast growth factor, and TGF-beta1 on cross-sections of the neointima were evaluated by immunohistochemistry. No significant differences were found regarding mean neointimal thicknesses. PDGF and TGF-beta-1 expressions were significantly lower in group 1. Although a decrease in local effect of tranilast was observed for growth factor expressions at a drug concentration of 0.05 mg/cm(2), a significant reduction in neointimal hyperplasia was not achieved. The coating concentration of 0.05 mg/cm(2) may have been too low to produce an antiproliferative effect. Given our promising results, further studies are recommended and planned using different drug concentrations and time intervals. 相似文献
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Pathological and molecular progression of astrocytomas in a GFAP:12 V-Ha-Ras mouse astrocytoma model 总被引:4,自引:0,他引:4 下载免费PDF全文
Shannon P Sabha N Lau N Kamnasaran D Gutmann DH Guha A 《The American journal of pathology》2005,167(3):859-867
We previously characterized a genetically engineered mouse astrocytoma model with embryonic astrocyte-specific, activated 12V-Ha-RAS (GFAP-RAS) transgenesis. The GFAP-RAS line Ras-B8 appears normal at birth, but 50% of mice die by 4 months from low- and high-grade astrocytomas. We examined the development and progression of astrocytomas in the Ras-B8 genetically engineered mouse. At embryonic day 16.5 (E16.5), there were no pathological differences compared to control littermates, aside from transgene expression. Diffuse astroglial hyperplasia was the first distinguishing feature in the 1-week-old Ras-B8 mice; however, these astrocytes were not transformed in vitro or in vivo. From 3 to 8 weeks the incidence of low-grade astrocytomas progressively increased with 85% of 12-week-old mice harboring low- or high-grade astrocytomas, the latter characterized by increased proliferation, nuclear atypia, and angiogenesis. Tp53 mutations were detected in both astrocytoma grades, with high-grade astrocytomas expressing elevated levels of epidermal growth factor receptor and vascular endothelial growth factor, plus decreased levels of PTEN and p16, similar to human astrocytomas. We postulate that expression of 12V-Ha-RAS in astroglial precursors induces astroglial hyperplasia, but transformation and subsequent progression requires additional molecular alterations resulting from aberrant activated p21-RAS. Of interest, many of these acquired alterations occur in human astrocytomas, further validating GFAP-RAS as a useful model for studying astrocytoma development and progression. 相似文献
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What evidence is there for the existence of individual genes with antagonistic pleiotropic effects? 总被引:6,自引:0,他引:6
Leroi AM Bartke A De Benedictis G Franceschi C Gartner A Gonos ES Gonos E Fedei ME Feder ME Kivisild T Lee S Kartaf-Ozer N Kartal-Ozer N Schumacher M Sikora E Slagboom E Tatar M Yashin AI Vijg J Zwaan B 《Mechanisms of ageing and development》2005,126(3):421-429
Classical evolutionary theory predicts the existence of genes with antagonistic effects on longevity and various components of early-life fitness. Quantitative genetic studies have provided convincing evidence that such genes exist. However, antagonistic pleiotropic effects have rarely been attributed to individual loci. We examine several classes of longevity-assurance genes: those involved in regulation of the gonad; the insulin-like growth factor pathway; free-radical scavenging; heat shock proteins and apoptosis. We find initial evidence that antagonistic pleiotropic effects are pervasive in each of these classes of genes and in various model systems--although most studies lack explicit studies of fitness components. This is particularly true of human studies. Very little is known about the early-life fitness effects of longevity loci. Given the possible medical importance of such effects we urge their future study. 相似文献
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Right ventricular free‐wall longitudinal speckle tracking strain in patients with pulmonary arterial hypertension under specific treatment 下载免费PDF全文
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The effect of inhaled corticosteroids on bronchoalveolar lavage cells and IL-8 levels in stable COPD patients 总被引:2,自引:0,他引:2
Chronic obstructive pulmonary disease (COPD) is characterised by a chronic inflammatory process in the large and small airways, as well as in the lung parenchyma. Although the role of oral corticosteroids in the management of acute exacerbations of COPD is well documented, its role in stable COPD is not clear. We examined the anti-inflammatory effect of inhaled budesonide on the percentage of neutrophils and on interleukin-8 (IL-8) levels in bronchoalveolar lavage (BAL) and their correlation with spirometry and symptom scores. Twenty-six patients with stable COPD were randomised, in a double-blinded, placebo-controlled trial with either 800 microg of inhaled budesonide or placebo for a 6-month period. The budesonide-treated subjects had significant reductions in IL-8 levels in the BAL after therapy (mean+/-sem, 1.53+/-0.72 at baseline vs. 0.70+/-0.48 ng/ml at 6 months, P=0.004) and a reduction in the mean percentages of neutrophils (17.16+/-2.67% vs. 13.25+/-2.28% P=0.002). The improvement in sputum production was of borderline (P=0.058) significance but there was no improvement in lung function. In stable patients with COPD, treatment with inhaled budesonide for a period of 6 months has a positive effect on markers of lung inflammation, as assessed by reduction in percentage neutrophils and IL-8 concentration in BAL. 相似文献
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Nesrin Saitogullari Ugurcan Sayili Esma Altunoglu Hafize Uzun 《Annales d'endocrinologie》2021,82(1):1-7
BackgroundThis study aimed to investigate the relationship between lipopolysaccharide (LPS) and zonulin levels and also to show the effect of acute hyperglycemic stress induced by oral glucose tolerance testing (OGTT) on zonulin levels in pre-diabetic patients.MethodsFour groups were constituted according to the criteria of the American Diabetes Association (ADA), based on OGTT results: control group (n:40); prediabetic group (n:56), divided into two subgroups: impaired fasting glucose group (IFG) (n:36), and impaired glucose tolerance (IGT) + IFG group (n:20) and type-2 diabetes mellitus (T2DM) group (n:45).ResultsZonulin and LPS did not significantly differ between the prediabetes and control groups, but were significantly higher in the T2DM group compared to both the prediabetic and the control group (P < 0.001). After OGTT, zonulin and LPS were significantly higher in the prediabetes group compared to the control group (P < 0.01 and P < 0.05, respectively), and significantly lower in the IFG and IFG + IGT groups compared to the T2DM group (P < 0.001, P < 0.001 and P < 0.001, P < 0.001, respectively). A positive correlation was detected between fasting zonulin and 2-hour zonulin (r = 0.727, P < 0.001) and between fasting LPS (r = 0.555, P < 0.001) and 2-hour LPS (r = 0.567, P < 0.001) in the prediabetic group. Increased zonulin and LPS levels and the positive correlation between these levels during the prediabetic period although non significant suggests onset of intestinal permeability.ConclusionsDuring acute hyperglycemia in prediabetic patients, up-regulation of zonulin and LPS may affect intestinal function. The intestines may play a key role in up-regulation of glucose and the pathogenesis of diabetes. 相似文献