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81.
Mutations of the mediator subcomplex 12 gene (MED12) recently have been described in a large group of uterine leiomyomas (UL) but only in a single malignant uterine smooth muscle tumor. To further address the occurrence of fibroid‐type MED12 mutations in smooth muscle tumors, we have analyzed samples from 34 leiomyosarcomas (LMS), 21 UL, two extrauterine leiomyomas (EL), and 10 canine genital leiomyomas for the presence of MED12 mutations of the UL‐type. Interestingly, besides UL MED12 mutations were found in one uterine LMS, one EL, and two canine vaginal leiomyomas. The results confirm the occurrence of fibroid‐type MED12 mutations in malignant uterine smooth muscle tumors thus suggesting a rare but existing leiomyoma‐LMS sequence. In addition, for the first time MED12 mutations are reported in smooth muscle tumors in a non‐primate mammalian species. © 2012 Wiley Periodicals, Inc.  相似文献   
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Objectives: To evaluate subjective discomfort and somnographic measures of patients with obstructive sleep apnea and snoring problems who had been treated for 2 years with a mandibular protruding device (MPD). Methods: The study population comprised 65 patients with a pretreatment diagnosis of obstructive sleep apnea (OSA) (n = 44) or habitual snoring without apnea (n = 21). After a baseline medical and somnographic examination, a functional examination of the stomatognathic system, and a questionnaire focused on sleep-related qualities, each patient received an MPD. Two follow-ups were made 6 months and 2 years after MPD treatment had been initiated, and all initial examinations were repeated. Results: At the 2-year follow-up, significant subjective improvements were registered in 90% of the patients regarding a reduction of snoring and apneas, in 76% regarding a reduction in daytime tiredness, and in 84% regarding an improvement in the quality of the night sleep (change of 50% from baseline data). At the 2-year follow-up of the OSA group, the oxygen desaturation index (ODI) had dropped significantly from a mean value of 14.7 (SD, 12.7) to 3.1 (SD, 4.2) (P < 0.001), and the mean SaO2 nadir rose from 78.2% (SD, 8.1) to 89.0% (SD, 4.7) (P < 0.001). Only one of the snorers increased his ODI value; the others retained their initial healthy values. The OSA patients significantly reduced the amount of time they snored during their sleep. Conclusion: MPD treatment is associated with a significant reduction in subjective complaints such as disturbing snoring, apneas, daytime tiredness, and poor quality of night sleep, and with a significant reduction in ODI values in the OSA group. In addition, favorable 6-month results were unchanged after 2 years.  相似文献   
84.
BACKGROUND: The clinical effects of percutaneous transluminal renal artery angioplasty (PTRA) in patients with renal vascular stenosis and hypertension is controversial. METHODS: We consecutively recruited all 23 patients referred for evaluation of renovascular hypertension that eventually underwent unilateral PTRA, to be investigated with captopril MAG3 renography (CR), both before and after the endovascular procedure. Data were evaluated on an intention-to-treat basis. RESULTS: We found that the relative MAG3 clearance of the stenotic kidney increased (from 29.9+/-14% to 35.1+/-14%, p=0.01) and that the creatinine levels fell following the intervention (from 110+/-19 to 99+/-17 micromol/l, p=0.0003). Blood pressure levels were also lowered (from 173+/-32/93+/-17 to 158+/-31/86+/-15 mmHg, p<0.006) while the mean number of anti-hypertensive drugs was unchanged following PTRA (2.9+/-1.4 before and 2.8+/-1.3 drugs after the intervention, respectively, p=0.6). CONCLUSION: This prospective trial showed statistically significant improvements of individual kidney function as measured by CR and blood pressure in subjects with suspected renovascular hypertension treated with PTRA. Although the endovascular procedure was found to be safe, the magnitude of the absolute improvements was rather modest.  相似文献   
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Although understanding the relation between psychotic behavior and immune abnormalities has been the focus of research for many years, it remains to be elucidated whether the changes in cytokine levels are part of etiology or a result of the stress associated with the disorder. In accordance with previous studies on changes in cytokine levels due to metabolic changes and psychosis, we hypothesized that fatty liver may potentiate apomorphine-induced stereotypy in a rodent model and that a synthetic glucagon-like peptide-1 analog exenatide would ameliorate this effect. In this study, 18 male Sprague Dawley albino mature rats were used. We induced hepatosteatosis in these rats by feeding them with 30% fructose dissolved in drinking water for 8 weeks. The animals were divided into three groups, namely, the normal group, the intracerebroventricular (ICV) exenatide group, and the ICV NaCl group. Apomorphine-induced stereotypic behavior test was performed in all groups and the liver was removed for histopathological examination after all the rats were euthanized. In the nonalcoholic fatty liver (NAFL) group, stereotypy scores were significantly increased compared with the control group rats (p < 0.00001). A significant decrease in stereotypy scores were observed in the ICV exenatide group with NAFL when compared with the ICV saline group with NAFL (p < 0.005). In addition, brain malondialdehyde and tumor necrosis factor-α levels decreased in the ICV exenatide group. The results of this study showed that fatty liver enhances the effect of apomorphine on stereotypy, which was reversed by exenatide possibly by antioxidant and anti-inflammatory effects.  相似文献   
87.
Many studies have demonstrated attenuated verbal working memory (WM) under articulatory suppression. However, performance is not completely abolished, suggesting a less efficient, non-articulatory mechanism for the maintenance of verbal information. The neural causes for the reduced efficiency of such a putative complementary maintenance system have not yet been addressed. The present study was conducted to fill this gap. Subjects performed a Sternberg task (a) under articulatory maintenance at low, high, and supracapacity set sizes and (b) under non-articulatory maintenance at low and high set sizes. With functional magnetic resonance imaging, set-size related increases in activity were compared between subvocal articulatory rehearsal and non-articulatory maintenance. First, the results replicate previous findings showing different networks underlying these two maintenance strategies. Second, activation of all key nodes of the articulatory maintenance network increased with the amount of memorized information, showing no plateau at high set sizes. In contrast, for non-articulatory maintenance, there was evidence for a plateau at high set sizes in all relevant areas of the network. Third, for articulatory maintenance, the non-articulatory maintenance network was additionally recruited at supracapacity set sizes, presumably to assist processing in this highly demanding condition. This is the first demonstration of differential neural bottlenecks for articulatory and non-articulatory maintenance. This study adds to our understanding of the performance differences between these two strategies supporting verbal WM.  相似文献   
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IntroductionWe have previously shown that different forms of stress have distinctive effects on atherogenesis in mice. We showed that social stress increase atherosclerosis in ApoE?/? mice, while more physical forms of stress do not. Here we evaluated the effect of social disruption (SDR) stress on atherogenesis and evaluated cytokine release after SDR-stress and five more physical stressors.MethodsMale ApoE?/? mice were exposed to SDR-stress during 12 weeks, and atherosclerotic plaque area was assessed in aorta, aortic root and innominate artery. Further, male C57BL/6 mice were exposed to SDR-stress or five physical stressors, and cytokine and corticosterone levels were analyzed in plasma/serum samples immediately after stress.ResultsWe found a correlation between the level of SDR-stress and atherosclerotic plaque area in aorta and a numerical increased plaque area in aortic root. SDR stress did not affect histological features of plaque composition. However, SDR-stress increased levels of corticosterone, IL-6 and CXCL1. Plasma corticosterone increased for all five physical stressors, but IL-6 and CXCL1 only increased in the group exposed to restraint combined with rat odor.ConclusionsThese findings suggest that SDR-stress is indeed atherogenic, in contrast to our previous results using the physical stressors. A possible explanation to this difference is that SDR-stress, but not physical stressors, leads to release of the pro-inflammatory cytokines IL-6 and CXCL1.  相似文献   
90.
Using ultralow light intensities that are well suited for investigating biological samples, we demonstrate whole-cell superresolution imaging by nonlinear structured-illumination microscopy. Structured-illumination microscopy can increase the spatial resolution of a wide-field light microscope by a factor of two, with greater resolution extension possible if the emission rate of the sample responds nonlinearly to the illumination intensity. Saturating the fluorophore excited state is one such nonlinear response, and a realization of this idea, saturated structured-illumination microscopy, has achieved approximately 50-nm resolution on dye-filled polystyrene beads. Unfortunately, because saturation requires extremely high light intensities that are likely to accelerate photobleaching and damage even fixed tissue, this implementation is of limited use for studying biological samples. Here, reversible photoswitching of a fluorescent protein provides the required nonlinearity at light intensities six orders of magnitude lower than those needed for saturation. We experimentally demonstrate approximately 40-nm resolution on purified microtubules labeled with the fluorescent photoswitchable protein Dronpa, and we visualize cellular structures by imaging the mammalian nuclear pore and actin cytoskeleton. As a result, nonlinear structured-illumination microscopy is now a biologically compatible superresolution imaging method.  相似文献   
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