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91.
The self-renewal versus differentiation choice of Drosophila and mammalian neural stem cells (NSCs) requires Notch (N) signaling. How N regulates NSC behavior is not well understood. Here we show that canonical N signaling cooperates with a noncanonical N signaling pathway to mediate N-directed NSC regulation. In the noncanonical pathway, N interacts with PTEN-induced kinase 1 (PINK1) to influence mitochondrial function, activating mechanistic target of rapamycin complex 2 (mTORC2)/AKT signaling. Importantly, attenuating noncanonical N signaling preferentially impaired the maintenance of Drosophila and human cancer stem cell-like tumor-forming cells. Our results emphasize the importance of mitochondria to N and NSC biology, with important implications for diseases associated with aberrant N signaling.  相似文献   
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The merits of surgical treatment of fractures of the mandibular condyle versus non-surgical management remains highly controversial, despite a large volume of literature dedicated to this topic. One reason the controversy remains, is because most of the outcomes in the literature are not directly comparable. The disparate range of condylar fracture classifications used is one of the reasons that studies are not comparable. We sought to review classification systems for condylar fractures used in the recent scientific literature.Review of the literature from 2016 to 2019, looking for papers relating to fractures of the mandibular condyle. Papers identified were assessed for type of study, focus of study, classification system used.88 studies were identified, including prospective and retrospective cohort studies, randomised and non-randomised prospective studies, randomised controlled trials and case series. More studies focussed on epidemiological factors than surgical access, fixation or outcomes. 31 used no classification system, whilst 17 used unique classification systems and 40 used previously referenced classification systems.Classification systems are used to help separate clinical problems into distinguishable groups, where there is a difference in management or outcome depending on the distinguishing features.There is currently a wide diversity of classification systems used for condyle fractures, and as a result, comparisons of surgical access, fixation and outcomes are difficult to make. Having a single classification system across the published literature would allow easier comparison and the classification proposed by the AO group is recommended for future use.  相似文献   
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Clinical Oral Investigations - 3D cephalometric analysis performed on cone-beam or multi-slice computed tomography (CBCT, MSCT) has superior diagnostic value compared to 2D cephalometry based on...  相似文献   
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BackgroundThe coronavirus diseases of 2019 (COVID-19) pandemic was classified as one of the worst pandemics in the 21st century. Its rapid transmission, unpredicted mortality rate, and the uncertainty surrounding its transmission method have evoked additional fear and anxiety. Nonetheless, to the best of our knowledge, no prior study has explored PTSD prevalence three months after the start of the quarantine procedures in Saudi Arabia nor has examined PTSD prevalence by three different methods.ObjectiveThis observational cross-sectional study aimed to identify the prevalence, severity, and influencing factors of PTSD in different regions of Saudi Arabia three months after the onset of the quarantine procedures related to the COVID-19 pandemic.MethodsThrough the month of June 2020, 1374 people (49.05% men and 50.95% women) completed a 35-item, 10-minute online. The prevalence of PTSD was measured using PCL-S (specific for COVID-19) that assesses the 17 symptoms of PTSD. Resilience was measured using 2-items Arabic version of the Connor-Davidson Resilience Scale 2 (CD-RISC 2).ResultsWe calculated the prevalence by three methods, namely, PTSD cut-off score, criteria, and combined, and the prevalence was 22.63%, 24.8%, and 19.6%, respectively. Female participants showed higher prevalence than male. As well, participants who were either tested positive or suspected of having been infected with COVID-19 showed higher PTSD prevalence. Higher resilience was associated with lower PTSD prevalence.ConclusionsThis was the first study to report PTSD prevalence by three differential methods three months after the onset of the quarantine procedures related to the COVID-19 pandemic in Saudi Arabia. We observed a significant impact of the COVID-19 pandemic in the Saudi population; therefore, great attention should be performed in implementing new procedures that deal with the highlighted risk factors, especially in vulnerable groups, to overcome the psychological impact of the COVID-19 pandemic.  相似文献   
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In this study, we aimed to compare the effects of dexpanthenol and N-acetylcysteine on wound healing. The wound healing process is a multifaceted sequence of activities associated with tissue restoration process. A number of investigations and clinical studies have been performed to determine new approaches for the improvement of wound healing. A total of 30 rats were divided into 3 equal groups. A linear 2-cm incision was made in the rats'' skin. No treatment was administered in the first (control) group. Dexpanthenol cream was administered to the rats in the second group and 3% N-acetylcysteine cream was administered to the rats in the third group. The wound areas of all of the rats were measured on certain days. On the 21st day, all wounds were excised and histologically evaluated. The epithelialization and granulation rates between the groups were revealed to be similar in microscopic evaluations. Although the fibrosis was remarkable in the control group as compared with the other groups, it was similar in N-acetylcysteine and dexpanthenol groups. Angiogenesis rate was remarkable in the N-acetylcysteine group compared with the others. In multiple-comparison analysis, Dexpanthenol and N-acetylcysteine groups had similar results in terms of wound healing rates (P < 0.05), which were both higher than in the control group (P > 0.05). The efficacy of N-acetylcysteine in wound healing is comparable to dexpanthenol, and both substances can be used to improve wound healing.Key words: N-acetylcysteine, Dexpanthenol, Wound healingWound healing is a multifaceted sequence of activities associated with the tissue restoration process.1 This activity takes place in 4 main steps: inflammation, proliferation, matrix deposition, and remodeling.2,3 Moreover, there are many factors that might have harmful effects on the wound healing process. In this regard, there have been numerous analyses and clinical studies aiming to find new methods for the improvement of wound healing processes.4Dexpanthenol is the biologically-active alcohol of pantothenic acid, which leads to an elevation in the amount of coenzyme A in the cell. Dexpanthenol is extensively used in topical form, since it can easily penetrate the skin even at large local concentrations. When used in formulations, dexpanthenol is most effective for the stimulation of epithelialization, granulation, and the mitigation of itching.5N-acetylcysteine (NAC) is a prodrug that supplies bioavailable cysteine for glutathione replenishment and prevents oxidative damage as well as inflammation. It also leads to glutathione (GSH) formation in the body. Besides fostering angiogenesis, it is used to scavenge free radicals. NAC has a number of functions in the stages of repair process, including cell proliferation, migration, and scratch wound healing. Moreover, NAC has also been reported to promote wound healing in diabetic rats.6In this study, we aimed to compare the effects of dexpanthenol, a molecule that is widely used to improve wound healing, and NAC, a molecule that reduces oxidative stress and inflammation, on wound healing.  相似文献   
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Hydatid cyst disease, which is endemically observed and an important health problem in our country, involves the spleen at a frequency ranking third following the liver and the lungs. In this study, we aimed to evaluate the efficacy and results of management in splenic hydatid cysts. The demographic data, localization, diagnosis, treatment methods, and the length of postoperative hospital stay of patients with splenic hydatid cysts in a 12-year period were evaluated retrospectively. Seventeen cases were evaluated. Among these, 13 were females and four were males. Seven had solitary splenic involvement, eight had involvement of both the spleen and the liver, and two had multiple organ involvement. Ten had undergone splenectomy, one had undergone distal splenectomy, and the remaining cases had undergone different surgical procedures. The patients had received albendazole treatment in the pre- and postoperative period. One patient had died secondary to hypernatremia on the first postoperative day. The clinical picture in splenic hydatid cysts, which is seen rarely, is usually asymptomatic. The diagnosis is established by ultrasonography and abdominal CT. Although splenectomy is the standard mode of treatment, spleen-preserving methods may be used.  相似文献   
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