Knockdown of polypyrimidine tract binding protein facilitates motor function recovery after spinal cord injury

After spinal cord injury(SCI),a fibroblast-and microglia-mediated fibrotic scar is formed in the lesion core,and a glial scar is formed around the fibrotic scar as a res ult of the activation and proliferation of astrocytes.Simultaneously,a large number of neuro ns are lost in the injured area.Regulating the dense glial scar and re plenishing neurons in the injured area are essential for SCI repair.Polypyrimidine tra ct binding protein(PTB),known as an RNA-binding protein,plays a key role in neu...     

Inhibition of microRNA-29b suppresses oxidative stress and reduces apoptosis in ischemic stroke

MicroRNAs(miRNAs) regulate protein expression by antagonizing the translation of mRNAs and are effective regulators of normal nervous system development, function, and disease. Micro RNA-29 b(mi R-29 b) plays a broad and critical role in brain homeostasis. In this study, we tested the function of mi R-29 b in animal and cell models by inhibiting mi R-29 b expression. Mouse models of middle cerebral artery occlusion were established using the modified Zea-Longa suture method. Prior to modeling, 50 nmol/kg mi R-29 b antagomir was injected via the tail vein. Mi R-29 b expression was found to be abnormally increased in ischemic brain tissue. The inhibition of mi R-29 b expression decreased the neurological function score and reduced the cerebral infarction volume and cell apoptosis. In addition, the inhibition of mi R-29 b significantly decreased the malondialdehyde level, increased superoxide dismutase activity, and Bcl-2 expression, and inhibited Bax and Caspase3 expression. PC12 cells were treated with glutamate for 12 hours to establish in vitro cell models of ischemic stroke and then treated with the mi R-29 antagomir for 48 hours. The results revealed that mi R-29 b inhibition in PC12 cells increased Bcl-2 expression and inhibited cell apoptosis and oxidative damage. These findings suggest that the inhibition of mi R-29 b inhibits oxidative stress and cell apoptosis in ischemic stroke, producing therapeutic effects in ischemic stroke. This study was approved by the Laboratory Animal Care and Use Committee of the First Affiliated Hospital of Zhengzhou University(approval No. 201709276 S) on September 27, 2017.     

Solubility of hydroxyapatite by solid titration at pH 3-4

OBJECTIVES: The solubility isotherm (S) of hydroxyapatite (HAp) is of fundamental importance to saliva chemistry, dental caries and related contexts. It has previously been shown that the locus of the S[HAp] is substantially lower than is commonly reported, and of different slope, probably due to HAps incongruent dissolution. The aim of the present study was to determine the S[HAp] over a wider pH range and to identify the precipitate formed at equilibrium in HAp solid titration. METHODS: The solid titration technique of Leung and Darvell (Leung VW-H, Darvell BW. Calcium-phosphate system in saliva-like media. J Chem Soc Faraday Trans 1991;87(11):1759-64.) was used to investigate the solubility behaviour of HAp at 37.0+/-0.1 degrees C in 100 mM aqueous KCl. The pH range studied overlapped that of earlier work from pH 3.6 to 5.2, for a reproducibility check and validation, and extended to pH approximately 2.9. XRD and EDX were used to identify the precipitates. SEM and TEM were used to observe the morphology. RESULTS: The previous S[HAp] reported by Chen et al. (Chen Z-F, Darvell BW, Leung VW-H. Hydroxyapatite solubility in simple inorganic solutions. Arch Oral Biol 2004;49(5):359-67.) was reconfirmed. An abrupt change of slope of S[HAp] was detected at pH approximately 3.9. No other phase than HAp was found at pH 3.2, 3.6 and 4.1. In particular, brushite (dicalcium phosphate dihydrate) was not detected, even below pH 3.9, where instead calcium-deficient HAp was formed. CONCLUSION: The solid titration method was reconfirmed as reproducible and to yield HAp from pH 2.9 to 5.2. The expected brushite did not appear, but rather a stable calcium-deficient HAp was consistently formed. The chemistry of calcium phosphates needs to be reevaluated.     

Characteristics of a cancerous cell line, HIOEC-B(a)P-96, induced by benzo(a)pyrene from human immortalized oral epithelial cell line

Oral squamous cell carcinoma (OSCC) is the most common malignant tumor in the oral and maxillofacial region. The mechanism of carcinogenesis of OSCC is still unclear. In vitro study on OSCC cell lines, especially derived from immortalized oral epithelial cells, is a very useful strategy to understand the mechanism of carcinogenesis. Based on our previous human immortalized oral epithelial cell (HIOEC) line, obtained from normal oral epithelial cells by transfection of HPV16 E6/E7 gene, a new cancerous cell line, HIOEC-B(a)P-96 (HB96), was established from the HIOEC by induction with benzo(a)pyrene. The characteristics of the HB96 cells such as cell morphology, ultrastructure, proliferation ability, invasion ability, and tumorigenesis were studied. The HB96 cells lost contact inhibition with uncontrolled cell division and obvious cell overlap, they were polygonal in shape and ununiform in size with increased ratio between nucleus and plasma. Increased proliferative ability and invasion ability were confirmed by the cell proliferation analysis and cell invasion assay, respectively. The tumorigenicity of well to moderately differentiated squamous cell carcinoma was confirmed in the nude mice experiments pathologically. Increased expression of HPV16 E6/E7 proteins and obvious correlation with decreased expression of p53 and Rb proteins was also confirmed by Western blotting. Thus, this HB96 cell line induced by benzo(a)pyrene from the HIOEC line is a useful tool to study the mechanism of carcinogenesis of OSCC in vitro for future genomic and proteomic analyses. It is also the first in vitro cancerous cell line of OSCC in China derived from immortalized oral epithelial cells.     

Endpoint quantitative PCR assays for Bacteroides forsythus,Porphyromonas gingivalis,and Actinobacillus actinomycetemcomitans

BACKGROUND: Conventional polymerase chain reaction (PCR) assays for periodontal pathogens are so sensitive that they detect infections of no clinical significance. Quantitative PCR (qPCR) may provide a solution to this problem. However, most qPCR systems require expensive real-time thermal cyclers. OBJECTIVE: Our goal was to develop qPCR assays which would allow endpoint quantification. MATERIALS AND METHODS: 16S rRNA primers for Bacteroides forsythus, Porphyromonas gingivalis, and Actinobacillus actinomycetemcomitans were adapted to the Amplifluor qPCR system, which incorporates fluorescein into the PCR product so that endpoint fluorescence is proportional to the original amount of template. DNA dilutions representing known numbers of cells were used as standard curves. Pooled subgingival plaques from the four deepest pockets of 21 severe adult periodontitis patients were assayed. Buccal molar supragingival plaque from 35 dental students provided healthy controls. Endpoint fluorescence was measured with a microplate reader. RESULTS: Optimized standard curves were linear in log-log or semilog fits over a range of 100-10(6) cells. Countable B. forsythus was present in all patients, with counts (as logs) from 2.4 to 7.3 (mean = 5.0), and 11 controls with counts from 2.1 to 4.5 (mean = 3.0). P. gingivalis was present in 11 patients and no controls, with counts from 2.2 to 4.7 (mean = 3.2). A. actinomycetemcomitans was present in two patients, with counts of 1.5 and 3.5. CONCLUSIONS: Amplifluor qPCR assays discriminated between plaque samples differing by one log or more, allowing major infections to be distinguished from minor ones. This approach allows high-throughput qPCR of plaque samples, using equipment available to many laboratories.     

口腔扁平苔藓病损区白细胞介素12p40和干扰素-γ的表达及意义

目的 探讨白细胞介素12p40(IL-12p40)及干扰素-γ(IFN-γ)在口腔扁平苔藓(OLP)病损形成及发展中的意义.方法 正常口腔黏膜组织11例,OLP组织43例,采用免疫组织化学Envision二步法检测IL-12p40和IFN-γ的表达情况,分析其与OLP患者临床病理特征的关系.结果 1)OLP组IL-12...     

慢性牙周炎患者血清生化指标分析

目的通过分析牙周炎患者和牙周健康者的血糖、血脂、血清钙水平,探讨血清生化指标的异常是否对牙周炎的发生发展起促进作用。方法研究对象225人均无全身系统性疾病,病例组为慢性牙周炎患者145人,以临床附着丧失（CAL）<3 mm或CAL≥3 mm分为轻度组和中、重度组,对照组为牙周健康者80人,空腹抽取静脉血,检测血糖、血脂和血清钙水平,用SPSS 12.0统计软件包对血清学指标进行统计分析。结果病例组和对照组血脂和血清钙水平无显著差异（P>0.05）,病例组血糖、低密度脂蛋白高于临界值者和高密度脂蛋白、血清钙低于临界值者比例明显高于对照组（P<0.05）,轻度组血糖、甘油三酯、低密度脂蛋白水平明显低于中、重度组（P<0.05。结论血糖、血脂升高,血清钙降低可能增加宿主对牙周炎的易感性和促进牙周炎的发展。     

A pilot study applying digital radiography for estimating ratio of supported single-root surface area

BACKGROUND: The prognosis of a tooth with periodontitis is affected by the amount of supporting bone. A key factor in retaining a tooth is the ratio of supported root surface. Currently, root surfaces cannot be accurately measured using conventional dental radiographs, which only measure the length of bone support on proximal surfaces. METHODS: Eight extracted, single-rooted teeth were 3-dimensionally digitized using a contact technique for true surface area measurements. Root length, projection area, and pixel values were then measured on digital radiographs. The accuracy of the ratio estimation of supported surface area from linear, area, and pixel values was calculated and compared. RESULTS: The mean error from linear estimation was 7.9%; the mean error from area estimation was 1.0%; and the mean error from pixel value estimation was 1.3%. One-way analysis of variance (ANOVA) showed significant differences in all estimations while Scheffé's analysis further revealed significant differences only in the linear estimation. CONCLUSIONS: A three-dimensional digitizing device could be used as a non-destructive method of measuring root surface area. The ratio of supported single-root surface area could be estimated with high accuracy from the projected area data acquired on the digital dental radiographs. The thickness data as reflected from the pixel values in the digital images did not improve the estimation accuracy. Estimations using only length data yielded significantly less accuracy. Digital dental x-ray images provide the potential for estimating the ratio of supported root surface efficiently.     

量子点荧光探针在人舌鳞状细胞癌组织中的应用研究

目的 通过免疫荧光技术,利用量子点荧光探针在人的舌鳞状细胞癌组织中检测特定蛋白,探讨量子点荧光探针在人舌鳞状细胞癌组织中的应用.方法 相同粒径的量子点通过问接免疫荧光技术分别对人舌鳞状细胞癌组织中的P53及Bcl-2蛋白进行特异荧光标记,荧光显微镜观察蛋白定位表达;不同粒径的量子点通过间接免疫荧光技术,在同一张舌鳞状细...     

白细胞介素-1单核苷酸多态性与甘肃回族、东乡族人群慢性牙周炎的相关性研究

目的 通过检测并分析白细胞介素(IL)-1B+3954位点的单核苷酸多态性(SNP),探索其与甘肃回族与东乡族人群慢性牙周炎的关系.方法 收集215例回族、东乡族慢性牙周炎患者及219例正常对照组健康者的静脉血,提取外周静脉血白细胞DNA,采用聚合酶链式反应-限制性片段长度多态性技术(PCR-RFLP)方法检测IL-1...