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91.
N6-methyladenosine (m6A), as a eukaryotic mRNA modification catalyzed by methyltransferase METTL3, is involved in various processes of development or diseases via regulating RNA metabolism. However, the effect of METTL3-mediated m6A modification in tooth development has remained elusive. Here we show that METTL3 is prevalently expressed in odontoblasts, dental pulp cells, dental follicle cells, and epithelial cells in Hertwig's epithelial root sheath during tooth root formation. Depletion of METTL3 in human dental pulp cells (hDPCs) impairs proliferation, migration, and odontogenic differentiation. Furthermore, conditional knockout of Mettl3 in Osterix-expressing cells leads to short molar roots and thinner root dentin featured by decreased secretion of pre-dentin matrix and formation of the odontoblast process. Mechanistically, loss of METTL3 cripples the translational efficiency of the key root-forming regulator nuclear factor I-C (NFIC). The odontogenic capacity of METTL3-silenced hDPCs is partially rescued via overexpressing NFIC. Our findings suggest that m6A methyltransferase METTL3 is crucial for tooth root development, uncovering a novel epigenetic mechanism in tooth root formation. © 2020 American Society for Bone and Mineral Research (ASBMR).  相似文献   
92.
BackgroundPyriform sinus fistula (PSF) is a rare congenital anomaly, and the preferred definitive treatment is yet to be verified. In this study, we investigated the treatment outcomes of PSF specifically comparing endoscopic-assisted surgery and endoscopic radiofrequency ablation (RA).MethodsThe medical records of patients treated for PSF at the Shanghai Children's Hospital between October 2016 and September 2019 were retrospectively evaluated.ResultsThere were 93 girls and 98 boys. The median age at onset and operation was 3 years and 5 years, respectively. Endoscopic-assisted surgery was performed in 143 patients. During the same period, RA was performed in 48 patients, and 10 of them concurrently underwent incision and drainage of neck abscesses. Longer hospital stay was found in the endoscopic-assisted surgery group than in the RA group (10.50 ± 3.93 vs. 5.02 ± 3.30 days, P < 0.001). Postoperative complications were not significantly different between the two groups, except for neck infection (0 vs. 8.3%, P = 0.004). After a median follow-up period of 21 months, no significant difference was found between the two groups in terms of recurrence (1.4% vs. 0, P = 0.560).ConclusionPatients treated with RA had a significantly shorter hospital stay than those treated with endoscopic-assisted surgery. Outcomes of endoscopic-assisted surgery and RA were not significantly different for the management of PSF and treatment method should be tailored to the patient.Level of evidenceIV.  相似文献   
93.
目的:观察通脉解痉汤联合康复训练治疗脑卒中后下肢痉挛的临床疗效及对痉挛指数、运动功能的影响。方法:采用随机数字表法将76例脑卒中后下肢痉挛患者随机分为对照组与观察组各38例。对照组行常规脑卒中对症治疗和康复训练治疗,观察组在对照组基础上加用通脉解痉汤治疗。比较2组临床疗效和治疗前后中医证候积分、痉挛指数、运动功能。结果:治疗前,2组中医证候积分比较,差异无统计学意义(P>0.05);治疗后,2组半身不遂、手足挛急、偏身麻木、舌强言謇、面色晦暗、手足肿胀等中医证候积分均降低(P<0.05),且观察组低于对照组(P<0.05)。观察组治疗总有效率92.11%,高于对照组78.95%(P<0.05)。治疗前,2组肌张力、腱反射、阵挛等痉挛指数量表(CSI)评分比较,差异无统计学意义(P>0.05);治疗后,2组肌张力、腱反射、阵挛CSI评分均降低(P<0.05),且观察组低于对照组(P<0.05)。治疗前,2组Fugl-Meyer运动功能量表(FMA)评分比较,差异无统计学意义(P>0.05);治疗后,2组FMA评分均升高(P<0.05)...  相似文献   
94.
目的 研究U形钛棒内固定系统结合峡部植骨治疗腰椎峡部裂的临床疗效.方法 纳入2015年2月~2018年12月本科收治的50例不伴有椎间盘突出及腰椎滑脱的单纯性腰椎峡部裂患者;累及节段L34例,L414例,L532例.采用节段内U形钛棒固定系统结合峡部植骨治疗30例(U形钛棒组),节段间椎弓根螺钉系统结合峡部植骨治疗20例(椎弓根钉组).对比两组术前及末次随访时的VAS评分、ODI指数以及腰椎活动度以及并发症发生情况.通过腰椎CT评价峡部骨折愈合情况.结果 所有患者随访12~24个月,平均(18.2±7.3)个月.末次随访时两组疼痛VAS评分、ODI指数较术前均显著降低(P<0.05),但两组间差异无统计学意义(P>0.05),但U形钛棒组腰椎活动度显著大于椎弓根钉组,差异有统计学意义(P<0.05).末次随访两组患者峡部裂骨性愈合时间无显著性差异(P>0.05).所有手术切口均Ⅰ期愈合,植骨骨性融合,无感染、慢性疼痛、内固定松动等并发症发生.结论 对于不伴有椎间盘突出及腰椎滑脱的单纯性腰椎峡部裂患者,节段内U形钛棒固定与节段间椎弓根钉固定结合峡部植骨治疗均能取得良好疗效,但前者更有利于保留腰椎的活动度.  相似文献   
95.
PurposeTo investigate the clinical characteristics, chemosensitivity, and outcome of metastatic upper tract urothelial carcinoma (UTUC).Patients and MethodsRecords of patients with metastatic UTUC since January 2005 were retrieved from a database that included clinical and survival data. Statistical analyses including survival and multivariate analyses of factors were respectively performed by the Kaplan-Meier method and Cox proportional hazard model.ResultsA total of 250 consecutive UTUC cases were evaluated. There were 56 patients (22.4%) with initially diagnosed stage IV disease. The most common metastatic sites were lung (39.6%), distant lymph nodes (39.2%), bone (19.6%), liver (18.0%), and adrenal gland (7.2%), respectively, and the local recurrence rate was 10.4%. Two hundred thirteen patients received first-line chemotherapy. The overall response rate was only 28.7% and the median progression-free survival time was only 5.0 months. The overall survival time of the cohort was 18.0 months. Multivariate analyses showed that initially diagnosed stage IV disease, number of metastatic organs ≥3, no response to chemotherapy and cycles of chemotherapy ≤2 were adverse prognosticators for overall survival.ConclusionUTUC presented to be more prone to metastasize than locally recur and thought to have low chemosensitivity. Stage IV disease at initial diagnosis, number of metastatic organs, response and cycles of chemotherapy were independent prognosticators for metastatic UTUC.  相似文献   
96.
目的探讨高分辨率MR(HRMR)血管壁成像(VWI)所测壁强化指数(WEI)评估颅内动脉瘤不稳定性的价值。方法回顾性分析174例未破裂颅内动脉瘤患者。以3D-DSA观察动脉瘤大小、位置、形态。基于HRMR血管壁成像主观评估是否有动脉瘤壁强化(AWE),并采用软件计算WEI。采用ELAPSS及PHASES评分评估动脉瘤生长风险及破裂风险。以Spearman相关分析观察WEI与动脉瘤生长及破裂风险的相关性。结果 174例患者共248个无症状未破裂颅内囊状动脉瘤,HRMR VWI示AWE 78个、无AWE 170个。AWE与无AWE动脉瘤大小、位置、形态、ELAPSS评分、生长风险、PHASES评分、5年破裂风险差异均有统计学意义(P均0.05)。AWE动脉瘤WEI高于无AWE动脉瘤(P0.001)。Spearman相关分析显示,WEI与动脉瘤3年、5年生长风险(r_s=0.40、0.40,P均0.01)及5年破裂风险(r_s=0.24,P0.01)均呈正相关。结论 HRMR VWI所测WEI越高,提示动脉瘤不稳定性越高。  相似文献   
97.
ObjectiveTo analyze the clinical characteristics and controllable risk factors of osteoporosis in elderly men with type‐2 diabetes mellitus (T2DM).MethodsA total of 250 elderly OP patients with T2DM were included in the present study. Patients with one or more common chronic diseases (including hypertension, coronary heart disease, heart failure, chronic bronchitis, chronic nephrosis, and cirrhosis), and a course of more than 3 years were defined as complicated with chronic diseases. Blood glucose, cholesterol, triglyceride, low‐density lipoprotein, high‐density lipoprotein, calcium, phosphorus, glycosylated hemoglobin, urea nitrogen, creatinine, fasting insulin, liver function, and 25‐hydroxy vitamin D3 levels were measured. Bone mineral density was also measured.ResultsA total of 16 patients (6.4%) had severe osteoporosis. Furthermore, 66 patients (26.4%) had blood glucose control that reached the standard, while 176 patients (70.4%) used more than two anti‐diabetic drugs. The serum testosterone level was lower than the median in 87 patients (34.8%) and in 56 smokers (22.4%). Furthermore, 138 patients (55.2%) were overweight and obese, six patients (2.4%) were underweight, 197 patients (78.8%) had chronic diseases, 88 patients (35.2%) were sticking to exercise, and 117 patients (46.8%) had less exercise. In addition, 92 patients (36.8%) were treated with osteotrophy‐protective agents, and 24 patients (9.6%) received anti‐osteoporosis therapy. Smoking, poor glycemic control, low testosterone levels, less exercise, and complications with chronic diseases were the most relevant controllable risk factors.ConclusionFor elderly male osteoporosis patients with type‐2 diabetes, smoking cessation, blood sugar control up to the standard, regular exercise, active prevention and treatment of complications, and appropriate testosterone supplementation are necessary for preventing and curing osteoporosis.  相似文献   
98.
99.
100.
目的:探讨一种不影响残存神经自行恢复的产瘫臂丛神经修复新方法。方法:将上干损伤部位行松解,不切除神经瘤,将其近端的颈5或颈7神经根和神经瘤远端的臂丛上干的神经束膜切开窗口,取颈丛皮支或前臂外侧皮神经前成多段(一般每段长约2.0-2.5cm),两端分别与颈5神经根和上干的神经束膜行端侧缝合,结果:8例患儿经术后1-11年(平均3年)的随访,4例的三角肌和肱二头肌骨力达4级和4^-级,4例达3例。3例后期进行了肩关节松解和旋前圆肌肌腱切断,结论:该方法既提供了可使损伤近端颈5神经根的新生纤维生长至上干的神经通道,又未阻断神经瘤内残存神经纤维的自行恢复,是治疗产瘫特别是Tassin2型的新术式。  相似文献   
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