Novel design of miniplate for fixation of fractures at transition zone of parasymphysis-body region of mandible – A clinical randomised study

Fractures through the mandible at the level of the parasymphysis extending obliquely and traversing through the transitional zone to body region are relatively common. Therefore, a surgeon should have an appropriate understanding of the biomechanics of different plating techniques to fix these fractures. There is always a dilemma for the surgeon as to whether to fix these mandibular segments with one or two miniplates, and the presence of mental neurovascular bundle makes it more challenging. A study was planned in the Department of Oral and Maxillofacial Surgery to evaluate a novel twin-fork design of a miniplate used for fracture fixation at the transition zone of parasymphysis and body region of mandible after an in-vitro study of same design, and provided encouraging results. A total of 30 patients (10 patients in three groups each) were included in the study. All patients were evaluated preoperatively and postoperatively for operating time, ease of placement of miniplate, occlusion, reduction of fracture, neurosensory disturbances and infection. The novel design of twin-fork−shaped miniplate proved to be superior to the conventional miniplate in terms of neurosensory (Fisher exact test 17.40; p = 0.003) and functional outcome. There was statistically significant difference (χ² = 13.895, p = 0.031) in postoperative reduction of fracture at week 4, indicating superiority of the twin-fork miniplate among the other conventional designs. The study concludes that the use of newly designed twin-fork−shaped miniplate should be encouraged in the fractures of transitional zone of parasymphysis-body region involving mental neurovascular bundle.     

The Course of Eating Disorders Involving Bingeing and Purging Among Adolescent Girls: Prevalence,Stability, and Transitions

Purpose

To quantify eating disorder (ED) stability and diagnostic transition among a community-based sample of adolescents and young adult females in the United States.

睡眠过渡过程监测的新方法

在系统水平上研究人脑的睡眠过渡过程,以寻求监测睡眠过渡过程的新方法.方法:让15名睡眠良好者进行睡眠中的行为反应实验,获取行为反应量.结果:发现行为反应量与脑电图所反映的脑状态一致,且能反应睡眠过渡过程中脑状态的微小变化.结论:以行为反应量监测睡眠过渡过程,结果可靠,操作简便,对被试者干扰小.     

High-Risk Drinking across the Transition from High School to College

Alcohol use and related problems were studied from the senior year in high school to the first autumn in college for 366 heavy drinking students. Four risk factors-subject sex, family history of drinking problems, prior conduct problems, and type of college residence-were evaluated as predictors of: (1) differential changes in drinking rates, (2) differential changes in alcohol-related problems, and (3) alcohol dependence symptoms during the first college term. Results suggest that both dispositional and environmental factors are associated with changes in drinking rates and the existence of dependence symptoms. Increases in the frequency of drinking were specifically and strongly associated with residence in a fraternity (men) or sorority (women). Three risk factors were associated with increased quantity of drinking: male gender, residence in a fraternity or sorority, and a history of conduct problems. Prior conduct problems were also consistently associated with dependence symptoms during the first term in college. A family history of alcohol problems was not consistently related to changes in use rates or problems, although some analyses suggest interactive effects. Early interventions on college campuses should target individuals using additive risk profiles.     

Contrasting mutation rates in mitochondrial and nuclear genes of yeasts versus mammals

Summary Base substitutions have been compared in two mitochondrial and two nuclear genes from three yeasts and three mammals. In yeasts, the two mitochondrial genes, cytochrome oxidase subunit 2 (COX2) and apocytochrome b (CYB), have fewer changes on a percentage basis than the nuclear-encoded cytochrome c (CYC) gene. By contrast, in mammals, the same mitochondrial genes have more mutations than CYC on a percentage basis. Sequence comparisons of the nuclear small-subunit ribosomal RNA (nSSU) gene shows that there are more substitutions per unit length in the three yeasts than in the three mammals. This result suggests that although the yeasts are more distantly related than the mammals, their mitochondrial genes have accumulated fewer changes.     

Distribution of neurons of origin of zinc-containing projections in the amygdala of the rat

The present study describes the distribution of neurons of origin of zinc-containing pathways in the amygdaloid complex of the rat, using the selenium method for simultaneous retrograde labeling of all zinc-containing neurons. With this method, vesicular ionic zinc is precipitated intravitally with selenium compounds and transported retrogradely to the parent neurons, where it can be visualized by silver amplification. Neurons labeled retrogradely with silver-amplified precipitate were observed in all amygdaloid nuclei except for the lateral olfactory tract nucleus, the accessory olfactory tract nucleus and the central nucleus. Very few labeled cell bodies were seen in the anterior amygdaloid area and the medial nucleus. The amygdalo-hippocampal area and the amygdalo-piriform transition area both showed a substantial number of labeled somata throughout their rostrocaudal extent. In the anterior cortical nucleus, very few labeled cell bodies were found in the rostral pole, whereas they were abundant in the caudal quarter of the nucleus. In the posterolateral cortical nucleus, the number of labeled cell bodies increased gradually; there were none in the rostral pole, but most of the neurons in the caudal part were labeled. The posteromedial cortical nucleus contained a great number of labeled somata, but with some variation in the rostrocaudal extent of the nucleus. Considerable numbers of labeled neurons were observed throughout the lateral nucleus. In the basolateral nucleus, a small number of labeled cell bodies was present in the rostral half, but a gradual increase was observed in the caudal direction. Finally, in the basomedial nucleus, very few labeled cell bodies were present in the rostral two-thirds, whilst a considerable number was encountered in the caudal one-third. Possible functional implications of neuronal zinc are considered. The distribution of neurons of origin of zinc-containing projections has been compared with previously described intrinsic connections of the rat amygdala, and tracts that may possibly be zinc-containing are outlined and discussed. It is concluded that in all probability a substantial proportion of the intrinsic connectivity of the rat amygdaloid complex is zinc-containing.The authors thank Ms. M. Sørensen, Mrs. A. Lyhr, Mr. A. Meier and Mrs. K. Wiedemann for excellent technical help.     

The epithelial-mesenchymal transition induces aggressivity of mucinous cystic neoplasm of the pancreas with neuroendocrine component: An immunohistochemistry study

Background

Pancreatic mucinous cystic neoplasms (MCN) are rare tumors that are usually diagnosed in females.

上调lncRNA SNHG12与miR-199a-5p/FZD6轴对肝细胞癌细胞增殖、侵袭和上皮-间质转化的影响

背景与目的：肝细胞癌（HCC）是临床上常见的恶性肿瘤之一,侵袭、转移和术后复发是导致HCC患者死亡的主要原因。目前认为长链非编码RNA（lncRNA）的失调可能与各类癌症的发生和转移有关。有研究显示lncRNA SNHG12在HCC组织表达明显上调,但其具体功能尚不清楚。故本研究探讨lncRNA SNHG12在HCC细胞中的作用及机制。 方法：用qRT-PCR检测SNHG12以及预测到的靶miRNA及靶基因（miR-199a-5p与FZD6）在HCC细胞HepG2细胞与人肝内胆管上皮细胞HIBEC中的基因表达量,观察下调SNHG12对HepG2细胞增殖、侵袭和上皮-间质转化（EMT）相关蛋白表达的影响;采用miRanda和双荧光素酶报告基因实验分析SNHG12和miR-199a-5p之间的关系,分析下调miR-199a-5p对HepG2细胞增殖、侵袭和EMT的影响,以及SNHG12对miR-199a-5p作用的影响;TargetScan和双荧光素酶报告基因实验分析miR-199a-5p和FZD6的关系;检测过表达及下调FZD6对HepG2细胞增殖、侵袭和EMT的影响,以及SNHG12和miR-199a-5p对FZD6表达的影响。 结果：与HIBEC细胞比较,HepG2细胞中SNHG12表达量明显升高、miR-199a-5p表达量明显降低、FZD6表达量明显升高（均P<0.01）。下调SNHG12表达,HepG2细胞增殖、侵袭和EMT被明显抑制,过表达SNHG12作用则相反（均P<0.05）。SNHG12与miR-199a-5p特异性结合,下调miR-199a-5p促进HepG2细胞增殖、侵袭与EMT,过表达miR-199a-5p则起到抑制作用（均P<0.05）。过表达miR-199a-5p对HepG2细胞的作用,能部分被同时过表达SNHG12所逆转（均P<0.05）。miR-199a-5p靶向FZD6,下调FZD6后HepG2细胞增殖、侵袭与EMT明显抑制,过表达FZD6则相反（均P<0.05)。下调SNHG12抑制FZD6的基因和蛋白表达,而下调miR-199a-5p则促进FZD6的表达（均P<0.01）;与单独下调miR-199a-5p比较,同时下调SNHG12和miR-199a-5p,FZD6的表达被抑制（P<0.01）。 结论：HCC细胞中lncRNA SNHG12的上调可能通过影响miR-199a-5p/FZD6轴促进HCC细胞的增殖、侵袭和EMT过程。     

三阴性乳腺癌细胞脂肪非典型钙黏蛋白4表达下调的生物学作用及机制

背景与目的 三阴性乳腺癌（TNBC）容易发生侵袭转移,恶性程度极高。笔者团队前期研究发现脂肪非典型钙黏蛋白4（FAT4）在TNBC组织中呈低表达且与预后相关,进而本研究进一步探讨FAT4对TNBC细胞生物学行为的影响,及其相关机制。方法 用qRT-PCR及Western blot检测正常人乳腺上皮细胞系（MCF-10A）及不同TNBC细胞系（BT-549、MDA-MB-231、MDA-MB-468、MDA-MB-436）中FAT4的表达水平。选择其中合适的TNBC细胞系,分别转染FAT4-shRNA（FAT4敲低组）、阴性对照序列（阴性对照组）,以未处理的TNBC细胞为空白对照组,分别采用CCK-8实验、流式细胞术、Transwell小室实验检测细胞增殖能力、凋亡率、侵袭与转移能力的变化,并用Western blot检细胞中Hippo信号通路下游靶点YAP及上皮间质转化（EMT）相关蛋白的变化。结果 与正常人乳腺上皮细胞比较,各TNBC细胞系中FAT4的mRNA与蛋白表达量均不同程度的降低（均P<0.05）。功能实验选用BT-549细胞和MDA-MB-436细胞。无论在BT-549细胞或MDA-MB-436细胞中,与空白对照组比较,FAT4敲低组在转染后24、48、72 h的增殖能力均明显升高、凋亡率明显降低、侵袭与转移能力明显增强（均P<0.05）;YAP蛋白表达量无明显变化（P>0.05）,但磷酸化YAP（p-YAP）表达量明显降低,上皮标志物E-cadherin水平明显降低,而间质标志物N-cadherin水平明显升高（均P<0.05）;阴性对照组与空白对照组间以上指标差异均无统计学意义（均P>0.05）。结论 FAT4表达水平在TNBC细胞中普遍降低,FAT4表达的降低能增强TNBC细胞增殖和侵袭迁移能力、减少TNBC细胞凋亡,其机制可能与FAT4降低后Hippo信号通路下游的YAP蛋白磷酸化减少,从而促进EMT进程有关。