升降散激活Wnt信号通路促进慢性脑缺血VD模型大鼠海马组织损伤修复

目的:升降散对血管性痴呆(VD)大鼠学习记忆能力的影响及神经保护分子机制。方法:SD大鼠70只,随机分为正常组、假手术组,模型组,阳性药物组(盐酸多奈哌齐,1 mg·kg-1),升降散低、中、高剂量组(0.67,1.33,2.66 g·kg-1),每组10只,除正常组和假手术组外,其余各组采用改良的2VO法制作慢性脑缺血VD模型,手术1周后开始给药,连续灌胃给药8周。采用2VO两血管阻断法观察升降散对VD各组大鼠学习和记忆的影响、定位航行和空间探索行为功能,分析其学习记忆和空间辨认的能力;采用苏木素-伊红(HE)染色考察海马区病理形态;利用蛋白质免疫印迹(Western blot)和免疫组织荧光化学染色法检测血管内皮生长因子(VEGF),巢蛋白(Nestin),Wnt信号通路关键蛋白,磷酸化低密度脂蛋白受体相关蛋白(p-LRP),磷酸化糖原合成酶激酶(p-GSK3β)和β-连环蛋白(β-catenin)的表达水平,初步探讨升降散对VD大鼠海马组织保护作用机制。结果:与模型组比较,升降散不同剂量组能不同程度延长VD大鼠的避暗实验的潜伏期、缩短VD大鼠水迷宫定位航行和空间探索实验的潜伏期,升降散呈剂量依赖性促进海马区的病理性损伤修复及VEGF和Nestin表达,升降散呈剂量依赖性上调海马组织Wnt信号通路关键蛋白p-LRP,p-GSK3β和β-catenin蛋白水平,均具有一定的统计学意义(P0.05,P0.01)。结论:升降散改善VD大鼠学习记忆和空间辨认的行为学能力可能与激活海马组织Wnt信号通路活性有关。     

蓝布正提取物对血管性痴呆大鼠学习记忆能力及海马NT-3,BDNF蛋白表达的影响

目的:观察蓝布正提取物(GHE)对血管性痴呆(VD)大鼠学习记忆能力的影响并探讨其作用的机制。方法:采用双侧颈总动脉结扎法制作VD大鼠模型,将大鼠随机分成假手术组,模型组,GHE高、中、低剂量组(7,3.5,1.75 g·kg~(-1))和阳性药组(天保宁银杏叶片,0.007 g·kg~(-1)),各组灌胃相应药物,每日1次,连续35 d,在第30~35天进行Morris水迷宫实验检测大鼠的学习记忆能力,Morris水迷宫实验结束后处死大鼠,收集大脑样本,免疫组化法检测海马CA1区B细胞淋巴瘤-2(Bcl-2)相关X蛋白(Bax),Bcl-2,神经营养因子-3(NT-3),脑源性神经营养因子(BDNF)蛋白表达。结果:与模型组比较,GHE高、中剂量组可明显缩短大鼠的逃避潜伏期,增加穿越平台数(P0.05);GHE高、中、低剂量组可显著降低海马CA1区Bax表达,升高Bcl-2,NT-3,BDNF表达(P0.05,P0.01)。结论:GHE能改善VD大鼠的学习记忆能力,其机制可能与促进海马CA1区NT-3,BDNF的表达,抑制神经细胞凋亡有关。     

Clinical application of a new compact CT system to assess 3-D images for the preoperative treatment planning of implants in the posterior mandible A case report

When treatment planning before placing dental implants in the posterior region of the mandible, the locations of the inferior alveolar nerve and mental foramen need to be ascertained, as they determine the bone height available and the implant length selected. The purpose of this study was to introduce the clinical application of a newly developed compact computed tomography system (Ortho-CT) to assess three-dimensional (3-D) images for the preoperative treatment planning of implants in the posterior region of the mandible. To evaluate the 3-D images, we scanned using the Ortho-CT system the mandible with a radiopaque template placed in the posterior region. The Ortho-CT images provided excellent information for evaluating the morphology of the mandible, and for showing the location of the inferior alveolar nerve, mental foramen and the relationship of the template to the bone. We consider that Ortho-CT is a useful aid to preoperative treatment planning of implant therapy in the mandible.     

Ultracytochemical localization of basal lamina anionic sites in the rat epithelial attachment apparatus

The basal lamina anionic sites of the epithelial attachment apparatus (EAA) were investigated at the electron microscopic level in adult rat periodontium. After 1M NaCl junctional epithelium detachment, an irregular and fluffy basal lamina-like structure appeared to cover the cementum surface. This structure reacted positively with polyethyleneimine (PEI), a strongly cationized ultrastruc-tural tracer, appearing to be composed of highly electron-dense microaggregates. Depending on section plane, double-tracked structures of undefined length were found within PEI precipitates and closely related to cementum collagen fibrils. After nitrous acid de-N-sulphation, 8 nm wide sets of two parallel lines were clearly identified. "Double tracks", i.e., sets of paired lines with peripherical PEI electron-dense material, were found to self-assemble to form dimers, clusters or more complex organizational patterns. From sensitivity towards nitrous acid oxidation and positive control observations, it was concluded that basal lamina anionic sites in the EAA. represented by PEI microaggregates, contain heparan sulfate proteoglycans (HSPGs). Furthermore, high resolution ultrastructural images demonstrated that HSPGs adopt a morphological appearance of "double tracks" in the tissue. On the other hand, the present findings suggest that HSPGs clusters, never found in the mucosal basement membrane used as positive control, may be related to a functional specificity of the tissue at the dento-gingival junction.     

The management of parotid tumors

The majority of salivary gland tumors are of epithelial origin. Parotid gland is the most common location of the tumors. Surgery is the main modality for the management of parotid tumors. Radiotherapy, chemotherapy etc are the auxiliary modalities.     

Correlation of mandibular bone quality with neurosensory disturbance after sagittal split ramus osteotomy

Our aim was to find out whether the quality of bone around the inferior alveolar nerve is correlated with neurosensory disturbance to the nerve after sagittal split ramus osteotomy (SSRO) in patients with mandibular prognathism. Computed tomograms (CT) were taken of 35 patients with mandibular prognathism and 35 without. To assess the density of bone around the inferior alveolar nerve, the width of the buccal cortical bone in the mandibular second molar regions was measured on CT. The Hounsfield units (HU) in the same regions were also measured. The number of HU in the mandible around the second molar regions was significantly higher (p < 0.01) in those with neurosensory disturbance (p < 0.01). The quality of bone measured by HU is associated with an increased risk of neurosensory disturbance, but the width of buccal bone is not.     

Expression of immunoregulatory molecules PD-L1 and PD-1 in oral cancer and precancerous lesions: A cohort study of Japanese patients

Objective

An association of the programmed cell death-1 (PD-1) and its ligand PD-L1 with various types of malignant tumors has been established. This study aimed to investigate the role of the PD-L1/PD-1 pathway in oral squamous cell carcinoma (OSCC) and oral epithelial precursor lesions (OEPL).

Iatrogenic injury to oral branches of the trigeminal nerve: records of 449 cases

The aims of this study were threefold: (1) to describe iatrogenic lesions to oral branches of the trigeminal nerve, signs and symptoms, and functional status, (2) to report on a simple neurosensory examination method, and (3) to discuss means of prevention of iatrogenic injury. The etiology and functional status of 449 injuries to oral branches collected over 18 years were retrospectively reviewed. A simple scheme of a clinical neurosensory examination was applied to enable a quantified rating of the perception. Injury to the lingual nerve (n = 261) is not only the most prevalent type of lesion, it also seems to be the most devastating type of lesion. Third molar surgery (n = 319) counts for the majority of injuries to the lingual, inferior alveolar, and buccal nerves. Lesions related to the injection of local analgesics was the second most frequent etiology (n = 78), and the lingual nerve was affected more frequently and severely than other oral branches of the trigeminal nerve. The female gender was overrepresented in incidence of injured nerves but no difference was found in the severity of affection between females and males. All grades of loss of neurosensory functions were found, and a range of neurogenic malfunctions was reported. Methodological obstacles in clinical neurosensory examination of trigeminal nerve injury and the magnitude of neurosensory impairment are discussed. Many nerve injuries are avoidable by critical reevaluation of indications, increased awareness of potential hazards, and modified surgical procedures.     

Mechanical properties of computer-aided design/computer-aided manufacturing resin composites assuming perfect silane coupling using in silico homogenization of cryo-electron microscopy images

Purpose

The aim of this study was to determine the mechanical properties of computer-aided design/computer-aided manufacturing (CAD/CAM) resin composites for dental restoration assuming perfect silane coupling by in silico homogenization analysis using a three-dimensional model constructed from cryo-electron microscopy (cryo-EM) images.