P2X_2和P2X_3受体在小鼠咽粘膜味蕾内的分布

应用免疫组织化学双标记技术研究ATP受体的P2X2和P2X3受体亚型在小鼠咽部粘膜味蕾和邻近组织内的分布,探究ATP在咽部味觉及一般感觉信号传导中的作用。在咽部各水平粘膜味蕾内均可观察到许多P2X2受体阳性味细胞和基细胞,未见P2X2受体阳性的神经纤维。许多降钙素基因相关肽(CGRP)阳性神经纤维围绕在味蕾周围,并发出分支与P2X2受体阳性味细胞和基细胞形成密切接触。P2X3受体多在咽部粘膜上皮味蕾内的神经终末表达,P2X3受体阳性纤维在粘膜基底部形成纤维束并与粘膜下P2X3受体阳性纤维相连,其分支在味蕾基底部形成神经丛,由神经丛发出神经终末到达顶部的味孔和味蕾各部,未见味蕾细胞表达P2X3受体。在无味蕾的粘膜上皮内,也观察到少量P2X3受体阳性神经终末。CGRP阳性纤维缠绕在味蕾周围,并发出分支与味蕾内的P2X3受体阳性纤维形成密切接触。上述结果表明ATP可能是咽粘膜内味觉信号感受与传导的神经递质。     

不同临床病理特征的食管鳞癌组织中上皮间质转化相关蛋白的表达

目的 探讨不同临床病理特征的食管鳞癌组织中上皮间质转化(EMT)相关蛋白的表达情况.方法 100例食管鳞癌患者,根据肿瘤芽数不同分为低肿瘤芽组(芽数<5个,n=40)及高肿瘤芽组(芽数≥5个,n=60),比较两组肿瘤组织中EMT相关蛋白上皮间质转化因子(Twist)、上皮性钙黏附因子(E-cadherin)以及β-连环蛋白(β-catenin)的表达情况,以及在不同临床病理特征中各相关蛋白的表达情况.结果 高肿瘤芽组Twist阳性表达率高于低肿瘤芽组,而E-cadherin及β-catenin阳性表达率低于低肿瘤芽组(均P<0.05).相较于无淋巴结转移者,有淋巴结转移者癌组织的Twist及β-catenin阳性表达率高,E-cadherin阳性表达率低(均P<0.05);随着疾病进展,Twist的阳性表达率降低(P<0.05);随着分化程度升高,E-cadherin的阳性表达率降低,β-catenin的阳性表达率升高(均P<0.05);随着肿瘤浸润深度增加,Twist、E-cadherin及β-catenin阳性表达率均升高(P<0.05).结论 Twist、E-cadherin以及β-catenin表达与食管鳞癌肿瘤芽形成、淋巴结转移以及浸润深度具有一定联系.     

舌神经切断吻合后菌状乳头味蕾再生的实验研究

目的：了解舌神经损伤后味蕾的变化，以及切断的舌神经用神经外膜吻合修复后舌菌状乳头和味蕾的再生能力。方法：模拟临床将SD大鼠一侧舌神经钳夹或切断损伤，即刻用神经外膜吻合的方法修复切断的舌神经．分别于术后20d和100d时用体视显微镜、组织显微镜、扫描电镜观察鼠舌菌状乳头和味蕾的形态和数目。结果：术后20d时，无论钳夹损伤或切断舌神经，切断的舌神经无论是否用神经吻合修复，舌神经损伤侧的菌状乳头和味蕾均萎缩、退化，数目明显减少；术后100d时，舌神经钳夹损伤和舌神经切断后即刻吻合修复的动物，退化、萎缩的菌状乳头和味蕾已完全再生，形态和数目恢复正常。而舌神经切断后未吻合的动物，萎缩、退化的菌状乳头和味蕾无明显再生恢复。结论：钳夹损伤舌神经，萎缩、退化的菌状乳头和味蕾可以自行再生恢复；切断舌神经，萎缩、退化的菌状乳头和味蕾不能自行再生恢复；用神经外膜吻合修复后，萎缩、退化的菌状乳头和味蕾可以再生恢复。舌菌状乳头和味蕾形态、数目的再生恢复，可以作为舌神经修复成功的客观指标。     

Assessment of oxidative stress responses and the cytotoxic and genotoxic potential of the herbicide tembotrione in HepG2 cells

Tembotrione is a triketone herbicide, usually used for post-emergence weed control in corn. Currently, there is little or no published data on its genotoxicity to human cells either in vitro or in vivo. This study evaluated the impact of acute (4 and 24 h) exposure to low concentrations of tembotrione [corresponding to the acceptable daily intake (0.17 μg/mL), residential exposure level (0.002 μg/mL) and acceptable operator exposure level (0.0012 μg/mL)] on human hepatocellular carcinoma cell line HepG2, using biomarkers of oxidative stress, CCK-8 colorimetric assay for cell viability, alkaline comet assay, and cytokinesis-block micronucleus “cytome” assay. Tembotrione applied at concentrations likely to be encountered in occupational and residential exposures induced cytogenetic outcomes in non-target cells despite non-significant changes in the values of oxidative stress biomarkers. We assume that the observed effects were mainly the consequence of impaired metabolic pathways in HepG2 cells due to the inhibition of the enzyme 4-hydroxyphenyl-pyruvate-dioxygenase by tembotrione, which possibly caused a depletion of folate levels leading to excess formation of nuclear buds in the affected cells. Regardless of the fact that tembotrione was previously reported negative for mutations and chromosome aberrations in vitro, our findings call for more precaution in its use.     

Innervation of single fungiform taste buds during development in rat

To determine whether the innervation of taste buds changes during postnatal development, the number of geniculate ganglion cells that innervated single fungiform taste buds were quantified in the tip- and midregions of the tongue of adult and developing rats. There was substantial variation in both the size of individual taste buds and number of geniculate ganglion cells that innervated them. Importantly, taste bud morphology and innervation were highly related. Namely, the number of labeled geniculate ganglion cells that innervated a taste bud was highly correlated with the size of the taste bud (r = 0.91, P < .0003): The larger the taste bud, the more geniculate ganglion cells that innervated it. The relationship between ganglion cell number and taste bud volume emerged during the first 40 days postnatal. Whereas there was no difference in the average number of ganglion cells that innervated individual taste buds in rats aged 10 days postnatal through adulthood, taste bud volumes increased progressively between 10 and 40 days postnatal, at which age taste bud volumes were similar to adults. The maturation of taste bud size was accompanied by the emergence of the relationship between taste bud volume and number of innervating neurons. Specifically, there was no correlation between taste bud size and number of innervating geniculate ganglion cells in 10-, 20-, or 30-day-old rats, whereas taste bud size and the number of innervating ganglion cells in 40-day-old rats were positively correlated (r = .80, P < .002). Therefore, the relationship between taste bud size and number of innervating ganglion cells develops over a prolonged postnatal period and is established when taste buds grow to their adult size. J. Comp. Neurol. 398:13–24, 1998. © 1998 Wiley-Liss, Inc.     

LABRADOR—A Computational Workflow for Virus Detection in High-Throughput Sequencing Data

High-throughput sequencing (HTS) allows detection of known and unknown viruses in samples of broad origin. This makes HTS a perfect technology to determine whether or not the biological products, such as vaccines are free from the adventitious agents, which could support or replace extensive testing using various in vitro and in vivo assays. Due to bioinformatics complexities, there is a need for standardized and reliable methods to manage HTS generated data in this field. Thus, we developed LABRADOR—an analysis pipeline for adventitious virus detection. The pipeline consists of several third-party programs and is divided into two major parts: (i) direct reads classification based on the comparison of characteristic profiles between reads and sequences deposited in the database supported with alignment of to the best matching reference sequence and (ii) de novo assembly of contigs and their classification on nucleotide and amino acid levels. To meet the requirements published in guidelines for biologicals’ safety we generated a custom nucleotide database with viral sequences. We tested our pipeline on publicly available HTS datasets and showed that LABRADOR can reliably detect viruses in mixtures of model viruses, vaccines and clinical samples.     

牛膝摘芽试验根形态变化的观察与比较

目的探索提高牛膝商品产量的种植管理新方法。方法摘芽后定期进行随机取样,并与对照组进行观察测量比较,追踪牛膝根外部形态的变化。结果摘芽后根的增长速度明显快于不摘芽组,摘芽组根比不摘芽组根长而粗大。结论牛膝种植过程中,采取摘芽措施可提高产品产量。     

不同分化阶段诱导性多能干细胞移植实验研究进展

诱导性多能干细胞（iPSCs）是由动物体细胞重编程得到的具有胚胎干细胞特性的全能干细胞。近年来,随着多能干细胞诱导技术的不断优化以及体外分化技术的飞速发展,多种分化状态的多能干细胞被用于移植实验。我们结合最新研究进展,阐述各种分化阶段诱导性多能干细胞用于动物移植治疗的优缺点,以及最新移植方法所存在的问题。     

甘草不定根培养的研究

[目的]考察甘草不同外植体与外源性激素诱导不定根能力,为甘草不定根培养做基础研究。[方法]切取乌拉尔甘草无菌实生苗的根、叶、带芽茎段接种到含有不同外源性激素的不定根诱导培养基中,考察不同外植体诱导生根的能力,并在此基础上进行不定根增殖尝试。[结果]不同外植体以及不同类型和浓度的外源性生长素对不定根诱导能力不同。根和叶诱导不定根效果好于带芽茎段;萘乙酸(NAA)较吲哚丁酸(IBA)更有利于不定根的诱导,6-苄氨基嘌呤(BA)则抑制不定根的诱导;不同类型的外植体诱导生根的生长素(NAA)适宜浓度存在差异,其中根段在0.2~1 mg/L,真叶在3~5 mg/L,带芽茎段在1~3 mg/L诱导效果较好。[结论]甘草不同外植体在含有外源性生长素的培养基中均可以诱导生根,但细胞分裂素强烈的抑制生根;根段和真叶作为外植体是甘草不定根诱导较为理想的材料。     

蒙古黄芪传粉特性研究△

目的:研究蒙古黄芪的传粉特性,为蒙古黄芪的新品种选育和良种繁育提供依据.方法:以蒙古黄芪为试材,采用自由授粉和套袋自花授粉2种授粉方式,研究黄芪的传粉特性;并通过剥蕾自交和花期喷施NaCl溶液,研究克服蒙古黄芪自交不亲和性的方法.结果:2种授粉方式的蒙古黄芪的亲和指数差异明显,自由授粉、套袋自花授粉的亲和指数分别为1.26和0,可见蒙古黄芪为异花授粉植物.剥蕾自交后,蒙古黄芪亲和指数为0.37,表明剥蕾自交是克服蒙古黄芪自交不亲和性的有效方法.而花期喷施NaCl溶液处理后,蒙古黄芪亲和指数仍为0.结论:黄芪是自交不亲和的异花授粉植物,剥蕾自交是克服蒙古黄芪自交不亲和性的有效方法.