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1.
《Dental materials》2022,38(8):1283-1300
ObjectivesTo compare new bone formation in mandibular critical-sized bone defects (CSBDs) in healthy, diabetic, osteoporotic, and diabetic-osteoporotic rats filled with bioceramics (BCs) with or without bone marrow mesenchymal stem cells (BMSCs).MethodsA total of 64 adult female Sprague-Dawley rats were randomized into four groups (n = 16 per group): Group 1 healthy, Group 2 diabetic, Group 3 osteoporotic, and Group 4 diabetic-osteoporotic rats. Streptozotocin was used to induce type 1 diabetes in Group 2 and 4, while bilateral ovariectomy was used to induce osteoporosis in Group 3 and 4. The central portion of the rat mandibular symphysis was used as a physiological CSBD. In each group, eight defects were filled with BC (hydroxypatatite 60% and β-tricalcium phosphate 40%) alone and eight with BMSCs cultured on BC. The animals were sacrificed at 4 and 8 weeks, and the mandibles were processed for micro-computed tomography to analyze radiological union and bone mineral density (BMD); histological analysis of the bone union; and immunohistochemical analysis, which included immunoreactivity of vascular endothelial growth factor (VEGF) and bone morphogenetic protein 2 (BMP-2).ResultsIn all groups (healthy, diabetics, osteoporotics, and diabetics-osteoporotics), the CSBDs filled with BC + BMSCs showed greater radiological bone union, BMD, histological bone union, and more VEGF and BMP-2 positivity, in comparison with CSBDs treated with BC alone (at 4 and 8 weeks).ConclusionsApplication of BMSCs cultured on BCs improves bone regeneration in CSBDs compared with application of BCs alone in healthy, diabetic, osteoporotic, and diabetic-osteoporotic rats.  相似文献   
2.
【摘要】 目的 对比分析单双侧经皮椎体成形术治疗骨质疏松性椎体压缩性骨折的临床效果。方法 选取2018 年 5 月至 2020 年 6 月河南省洛阳正骨医院收治的 104 例骨质疏松性椎体压缩性骨折患者作为研究对象, 并按照治疗方法将其分为单侧组与双侧组, 每组 52 例。单侧组患者采用单侧经皮椎体成形术治疗, 双侧组患者采用双侧经皮椎体成形术治疗, 对比两组患者手术时间、视觉模拟评分法 (VAS) 评分、椎体前缘高度、Cobb 角以及并发症发生情况。 结果 单侧组患者手术时间明显短于双侧组 (t = 29.664, P < 0.001); 术后 1 个月, 单侧组患者VAS评分、椎体前缘高度及 Cobb 角与双侧组无明显差异 ( t = 0.312、0.487、0.657, P = 0.756、0.627?0.513); 单侧组患者并发症发生率与双侧组无明显差异 (χ2= 0.343, P = 0.558)。结论 单双侧经皮椎体成形术治疗骨质疏松性椎体压缩性骨折均可取得满意的治疗效果, 但单侧经皮椎体成形术手术时间较短, 操作更简便。  相似文献   
3.
骨质疏松症是一种全身性骨代谢病,由多种因素引起,其特点是骨量、骨密度和骨组织的显微结构恶化,骨脆性增强和易发生骨折。骨质疏松症已严重威胁人类健康,最终将导致患者日常活动减少,生活质量降低,死亡率增加。针对不同的研究对象,选择一个正确、理想的动物骨质疏松的模型和实验方法以尽可能再现人类骨质疏松的状态,是开展动物实验的关键。我们综述了当前原发性和继发性骨质疏松等动物模型的构建,以及利用这些模型进行给药实验的研究方法,并对研发治疗骨质疏松的新型药物的选择提供了一些参考建议,以期对后续关于药物的作用机制、研发新药、药物的改良等研究提供思路。  相似文献   
4.
Lateral lymph nodes in low, locally advanced, rectal cancer have proven implications for local recurrence rates, which increase drastically in the presence of persistently enlarged lateral lymph nodes. These clinical implications warrant a thorough understanding of lateral nodal disease with awareness and knowledge from all three specialties involved – radiology, radiation oncology, and surgery – to ensure proper treatment. Relevant literature for each specialty, including all current guidelines and perspectives, were examined. Variations in definitions and treatment paradigms were evaluated. There is still no consensus for the standardized treatment of lateral nodal disease. Each discipline works according to their own available evidence, but relevant data are scarce. Current international guidelines and standard recommendations for the diagnostics and treatment of lateral lymph nodes are lacking. This results in differing perspectives and interpretations between the disciplines which can lead to challenging communication in an area where multidisciplinary collaboration is essential. This review addresses this by presenting the current evidence, perspectives and practices of each specialty and makes suggestions for each phase of the diagnostic and treatment process for patients with lateral nodal disease. By doing this, steps are taken toward achieving international consensus, and multidisciplinary collaboration.  相似文献   
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6.
目的 运用网络药理学和分子对接的方法研究益肾健骨方治疗绝经后乳腺癌骨质疏松症的作用机制。方法 通过中药系统药理数据库和分析平台(TCMSP)和中医综合数据库(TCMID)获取益肾健骨方的活性成分和靶点,以口服生物利用度(OB)≥30%和类药性(DL)≥0.18为阈值进行潜在活性成分筛选。通过药物靶标数据库(TTD)、药物数据库(DrugBank)、疾病相关的基因与突变位点数据库(DisGenet)数据库收集疾病靶点,筛选出与益肾健骨方的交集靶点。运用Cytoscape3.7.2构建疾病-化合物-靶点网络,蛋白相互作用网络(PPI)。采用Metascape进行基因本体(GO)功能富集分析和京都基因与基因百科全书(KEGG)通路富集分析,通过分子对接将关键靶点和潜在靶点与活性成分的相互作用进行验证。结果 益肾健骨方中共筛选到药代动力学较好的活性成分β-谷甾醇、谷甾醇、豆甾醇、槲皮苷、山柰酚等113种,得到GO富集条目(P<0.05)1048条,KEGG通路富集得到84条信号通路(P<0.05)。分子对接结果显示槲皮苷与核心靶点和潜在靶点结合稳定,涉及肿瘤通路、人乳头瘤病毒感染通路、PI3K-Akt信号通路等。大鼠体内实验验证益肾健骨方可以增加骨小梁密度及骨组织胶原溶剂比,改善大鼠骨质疏松状态。结论 益肾健骨方可能通过多靶点、多通路治疗乳腺癌绝经后骨质疏松症。  相似文献   
7.
《Saudi Dental Journal》2022,34(5):385-389
PurposeThis work aimed to study the rate and quality of maturation of the mineral component of retained teeth 3.8, 4.8 and lower jaw fragment of a human in connective tissue dysplasia in different periods of postpartum ontogenesis.MethodsThe study involved 102 men (76 with connective tissue dysplasia and 26 without connective tissue dysplasia) divided into groups by age: 31–40, 41–50, 51–60 years. One tooth 3.8, 4.8 and a fragment of the alveolar part of the lower jaw in the projection of teeth 3.8, 4.8 0.5*0.5 cm in size were extracted from each examinee for medical indications.ResultsLow optical density values are observed at the age of 41–50 years, at the age of 51–60 years, indicating decreased mineral density and the presence of total areas of hypomineralization from the age 31–40 years in connective tissue dysplasia. At the age of 41–50, 51–60 years, at the boundary of connective tissue structures and periosteum, a pronounced sclerosis and deformation of delineation elements were observed; at the age of 31–40 years, the indicated changes were less pronounced. At the age of 31–40 years, the level of bone plate dissection has a local character, after 40 years, it has a generalized character.ConclusionProgressive osteoporosis of the mandible and incomplete amelogenesis are an obstacle to the correct and harmonious teething of the lower wisdom teeth after the age of 30.  相似文献   
8.
Anthropomorphic measures among type 1 diabetic patients are changing as the obesity epidemic continues. Excess fat mass may impact bone density and ultimately fracture risk. We studied the interaction between bone and adipose tissue in type 1 diabetes subjects submitted to two different clinical managements: (I) conventional insulin therapy or (II) autologous nonmyeloablative hematopoietic stem-cell transplantation (AHST). The study comprised 3 groups matched by age, gender, height and weight: control (C = 24), type 1 diabetes (T1D = 23) and type 1 diabetes treated with AHST (T1D-AHST = 9). Bone mineral density (BMD) and trabecular bone score (TBS) were assessed by dual X-ray absorptiometry (DXA). 1H Magnetic resonance spectroscopy was used to assess bone marrow adipose tissue (BMAT) in the L3 vertebra, and abdominal magnetic resonance imaging was used to assess intrahepatic lipids (IHL), visceral (VAT) and subcutaneous adipose tissue (SAT). Individuals conventionally treated for T1D were more likely to be overweight (C = 23.8 ± 3.7; T1D = 25.3 ± 3.4; T1D-AHST = 22.5 ± 2.2 Kg/m2; p > 0.05), but there was no excessive lipid accumulation in VAT or liver. Areal BMD of the three groups were similar at all sites; lumbar spine TBS (L3) was lower in type 1 diabetes (p < 0.05). Neither SAT nor VAT had any association with bone parameters. Bone marrow adipose tissue (BMAT) lipid profiles were similar among groups. BMAT saturated lipids were associated with cholesterol, whereas unsaturated lipids had an association with IGF1. Overweight and normal weight subjects with type 1 diabetes have normal areal bone density, but lower trabecular bone scores. Adipose distribution is normal and BMAT volume is similar to controls, irrespective of clinical treatment.  相似文献   
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10.
目的:评价不同骨水泥输送装置经皮椎体成形术(percutaneous vertebroplasty,PVP)对椎体形态及骨水泥填充弥散的影响。方法:对2016年1月至2017年12月收治的52例单节段骨质疏松性椎体压缩骨折(osteoporotic vertebral compression fractures,OVCFs)进行回顾性分析。根据手术中骨水泥注入方法的不同将52例患者分为液压组(28例)和推杆组(24例)。比较两组患者手术前后VAS评分,观察手术前后病椎椎体前缘高度、椎体压缩比、后凸角,分析术后侧位椎体前1/3、中线、后1/3骨水泥填充比和正位X线片中骨水泥弥散情况,评价不同骨水泥输送装置PVP术后对椎体形态及骨水泥弥散可能产生的影响。结果:所有患者术后VAS评分较术前明显改善,液压组优于推杆组(P0.05)。椎体前缘高度、椎体压缩比及后凸角较术前均有明显恢复(P0.05),组间比较差异无统计学意义(P0.05)。侧位X线片骨水泥填充比,两组在椎体前1/3及中线处差异无统计学意义(P0.05),但在椎体后1/3处差异明显(P0.05);正位X线片上液压组骨水泥弥散更加显著(P0.05)。结论:液压式PVP术具有更佳的临床疗效,能保证骨水泥在骨折椎体内充分填充,能更好地恢复椎体形态,是一种有效的新技术,值得在临床推广应用。  相似文献   
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