长爪沙鼠舌下腺IgA的免疫组织化学研究

利用免疫组织化学等方法,测定不同年龄段实验长爪沙鼠舌下腺IgA的定位分布情况。结果表明,长爪沙鼠的舌下腺由导管部和分泌部构成,分泌部主要由粘液腺构成,其间散在分布有浆液腺细胞;导管部包括闰管、分泌管和小叶间导管等。粘液腺泡内含酸性粘多糖,浆液腺泡内主要以中性粘多糖为多,IgA阳性细胞主要分布于闰管、分泌管和小叶间导管,少量分布于腺泡和腺管间结缔组织,IgA阳性产物无明显规律性年龄变化,主要分布于胞质,胞核。     

长爪沙鼠内脏器官质量测定

长爪沙鼠 (ＭｅｒｉｏｎｅｓＵｎｇｕｉｃｕｌａｔｕｓ)越来越广泛地应用于生命科学的研究领域 ,但由于长爪沙鼠做为实验动物的历史尚短 ,对长爪沙鼠生理、解剖方面的报道甚少 ,为此笔者对长爪沙鼠的主要内脏器官及体长进行了测定。1　材料与方法1.1　材料1.1.1　动物　选驯养早期 ,但尚未完全适应饲养环境的野生长爪沙鼠 60只 ,其中雌性 2 2只 ,雄性 3 8只 ,体质量均在 42～114ｇ ,成龄未交配过。1.1.2　器材　扭力天平、尺、手术刀1.1.3　药品乙醚1.2　方法先将长爪沙鼠用乙醚麻醉 ,称体质量、量体长和尾长 ,然后断头取血 (供血检查用 ) ,…     

长爪沙鼠组织乳酸脱氢酶同工酶测定

应用聚丙烯酰胺凝胶电泳法测定长爪沙鼠的心、肝、肾、脾、胃、肺等６种组织乳酸脱氢酶同工酶的分布特异性，为应用长爪沙鼠作为实验动物的研究工作提供了重要的生化数据。     

长爪沙鼠早期驯育及主要脏器测定

对野生长爪沙鼠做了系列的实验动物化研究。用乙醚浅麻醉法解决了同居时的殴斗伤亡。肯定了一雄一雌频密繁殖法的优点，测定了心、肝、肾、脾、等主要脏器重量值，并发现野生鼠略大于驯化鼠。     

长爪沙鼠种群数量预测的模糊聚类方法

采用１９８８－１９９５年全野外调查所获的长爪沙鼠，逐月种群密度（绝对数量）、繁殖指数和壮龄模糊聚类，预测种群数量。提前２个月预测结果，准确率达到６２．５１－９８．１９％，平均为８０．５６％，其中对３、６、７、１１月份数量预测准确度最高，均大于９２．３５％；提前６个月预测结果，准确率达到４７．２２－９３．７２％，平均为８１．６４％，其中对５、７、９月份预测效果最好，准确率均大于９２．７９％；提前１１     

驯养后野生长爪沙鼠对饥渴的忍耐力

长爪沙鼠 (ＭｅｒｉｅｎｓＵｎｇｕｉｃｕｌａｔｕｓ)属于哺乳纲 ,仓鼠科 ,沙鼠亚科 ,沙鼠属 ,又名黄耗子、沙鼠、沙土鼠、羚羊鼠等。产于我国的东北北部 ,内蒙、中近东、非洲及东欧等地。是一种正在开发 ,有着广阔应用前景 ,多功能性的实验动物。由于野生长爪沙鼠长期栖息在干燥地区 ,故对饥渴的忍耐力很强。现将笔者试验驯养后的长爪沙鼠对饥渴的耐受力试验观察报告如下。1　材料与方法1.1　动物选经过哈医大实验动物学部驯养多年的野生长爪沙鼠90只 ,雌雄各半 ,体质量均在 6 8～ 97ｇ。1.2　方法　　将 90只雌、雄各半长爪沙鼠随机分成 3…     

不同地域长爪沙鼠群体间遗传状况分析

应用27个生化基因位点,分别对首都医科大学实验动物科学部和浙江省实验动物中心饲育的2个长爪沙鼠群体进行了遗传分析。结果显示,首都医科大学实验动物科学部长爪沙鼠群体遗传适应性、遗传多样性水平、遗传变异程度都明显高于浙江省实验动物中心沙鼠群体（P〈0.05）,并且这2个沙鼠群体间未出现较为明显的遗传分化（FST〉0.05）。     

瑞香狼毒根对长爪沙鼠的急性毒力测试

本文采用含17%瑞香狼毒(Stellera chamaejasme)根粉末的毒饵,依据孙氏改良寇氏综合计算法,实验室内测定了其对长爪沙鼠(Meriones unguiculatus)的急性毒力。根据预试验结果,采用最低剂量为7.0 g·kg^-1,最适剂量梯度比值K=0.65的5个剂量梯度的瑞香狼毒根毒饵饲喂长爪沙鼠。结果显示:试验组试鼠体重明显下降(P=0.029<0.05),完全致死组肝脏重/体重比对照组明显减小(P=0.014<0.05),但肾脏略增大(P=0.102>0.05)。其对长爪沙鼠的LD50为(20.37±0.086)g·kg^-1,95%平均可信限为(20.37±7.84)g·kg^-1,属弱毒水平。     

Spontaneous Basal cell carcinoma of the submandibular gland in a rat

At necropsy, a white nodule (about 5 × 3 mm in size) was observed in the right submandibular gland of a 10-week-old female GALAS rat. Histopathologically, oval to spindle-shaped and pale basophilic tumor cells proliferated closely, and formed variably sized foci. The nodule partially spread into or invaded the surrounding normal tissue, and necrotic foci were recognized in the tumor. Immunohistochemically, the nuclei of the tumor cells showed a diffusely positive reaction for p63, and the cytoplasm showed a diffusely positive reaction for cytokeratin and negative reaction for αSMA, vimentin, desmin and S-100. Many tumor cells were positive for PCNA. Ultrastructurally, the tumor cells contained many tonofilaments in the cytoplasm and a few desmosomes at the intercellular portion. Based on these findings, the tumor was diagnosed as a basal cell carcinoma originating from the duct in the rat submandibular gland.     

Spontaneous necrotizing sialometaplasia of the submandibular salivary gland in a Beagle dog

A single mass was found on the left submandibular salivary gland at necropsy of a 15-month-old male commercially bred laboratory Beagle dog from a control dose group from a repeat toxicity study. Microscopically, the mass was composed of a well-demarcated area of coagulative necrosis surrounded and separated from the normal salivary gland tissue by a thick fibrovascular capsule. Necrosis was admixed with areas of hemorrhage, fibrin, edema, fibrinoid necrosis of the vascular tunica media, and thrombosis of small and large vessels. Within the necrotic tissue, there was marked ductal hyperplasia, and squamous metaplasia of duct and acinar epithelium. The mass was diagnosed as necrotizing sialometaplasia of the submandibular gland. Hyperplastic ductal elements and squamous metaplasia can be mistaken microscopically with squamous cell carcinoma. Therefore, pathologists should be aware of this lesion as to avoid errors in the diagnosis of this benign pathologic condition.     

Localization of the sheep FcRn in the mammary gland

Among the multiple functions, which have been identified for the neonatal Fc receptor (FcRn), we study its role in the IgG transport in the mammary gland during the colostrum formation. For this reason, we have obtained several mammary gland biopsies from a pregnant sheep around parturition. The presence of the FcRn heavy chain mRNA was detected exclusively in the acinar and ductal epithelial cell by in situ hybridization (ISH). We detected strong signal in samples harvested 24 and 10 days prepartum; however, in samples we collected postpartum was barely detectable. Immunohistochemistry confirmed our ISH data. The cytoplasm of the epithelial cells of the acini and ducts in the mammary gland biopsies stained homogeneously before parturition, although a remarkable difference was observed in the pattern after lambing. The signal indicated uneven distribution of the FcRn alpha chain in the epithelial cells 1 and 5 days postpartum, since the apical sides of the epithelial cells were highlighted. The presence of the FcRn in the acinar and ductal epithelial cells and the obvious change of its distribution before and after parturition suggest that FcRn plays an important role in the IgG transport during colostrum formation. FcRn expression was also found in the lamb duodenal crypt epithelial cells, which have been previously demonstrated to secrete IgG1 in newborn ruminants, suggesting secretory role of the FcRn in ruminant epithelial cells.     

Distribution of sympathetic and afferent neurones innervating the submandibular gland in the sheep

The distribution of sympathetic and sensory neurones innervating the submandibular gland (SMG) in sheep was studied using retrograde tracing technique. The retrograde tracer Fast Blue (FB) was unilaterally injected into the SMG in five juvenile male sheep under general anaesthesia. After a 4-week survival period, all the animals were reanaesthetized, perfused transcardially with 4% buffered paraformaldehyde and ganglia, which could be considered as a potential sources of sympathetic, and afferent innervation of the gland were bilaterally collected. The FB-labelled sympathetic neurones were found in the ipsilateral superior and middle cervical ganglion. Many labelled neurones were distributed in the ipsilateral jugular and nodose ganglia of the vagus nerve and smaller numbers of the nerve cells were also found in ipsilateral C1-C3 dorsal root ganglia (DRG). No labelled neurones were observed in the ipsilateral stellate ganglion, trigeminal ganglion, C4-C8 DRG and in all contralateral ganglia. The present study revealed that the majority of sympathetic neurones projecting to the sheep SMG are found in the superior cervical ganglion but some of them are also distributed in the middle cervical ganglion. Most of the afferent neurones are located in the jugular and nodose ganglia of vagus nerve but C1-C3 DRG also comprise some of these nerve cells.     

Localization of glycoconjugates in dog parotid gland by lectin histochemistry

Parotid glands from adult dogs were stained with a battery of seven horseradish peroxidase-conjugated lectins (PNA, UEA, LTA, DBA, SBA, WGA and ConA). In some cases (PNA and DBA) neuraminidase digestion was followed by lectin staining. Acinar cells contained conspicuous quantities of oligosaccharides with terminal sialic acid radicals. Galactosil-(13)N-acetylgalactosamine was the most abundant penultimate sugar linked toN-acetylneuraminic acid. Sialylated components having the terminal dimer sialic acid-N-acetylgalactosamine were found in the acinar cells. Secretory cells presented a heterogeneous distribution of glycoconjugates with terminal fucose and -N-acetylgalactosamine. Fucose,N-acetylglucosamine and -N-acetylgalactosamine were present on the apical cytoplasm and surface of the striated and interlobular duct cells. This glycosidic composition was unaffected by extensive selective breeding. The role of abundant amounts of sialic acid radicals in the oral mucosa was considered.Abbreviations HRP horseradish peroxidase - PBS phosphate-buffered saline see also Tables I and III     

Localization of foot-and-mouth disease viral antigens in mammary gland of infected cows

Virolactias as a result of foot-and-mouth disease infection in dairy cattle would indicate active virus replication in the bovine mammary gland. In the present study, virus was readily detected throughout the mammary gland by infectivity assay after cows were exposed to the virus either by aerosol or by a combination of intramammary-IV inoculation. Furthermore, immunofluorescent and hematoxylin and eosin staining of alternate frozen sections showed viral antigens in rounded alveolar cells with pyknotic nuclei.     

Secretory component and IgA expression by epithelial cells in sow mammary gland and mammary secretions

Secretory component (SC) and IgA expression of epithelial cells were studied in the mammary tissue and mammary secretions of sows. In mammary tissue, SC was not detected until day 105 of gestation. From the time of delivery (day 115) to the time of established lactation, the proportion of epithelial cells containing sc rose from 20 per cent to nearly 100 per cent. There was no IgA in alveolar epithelial cells until day 105 of gestation; on day 115, IgA positive epithelial cells were present in 10 per cent of the alveoli, which increased to 80 per cent during lactation. Epithelial cells represented more than 20 per cent of the total cells in colostrum, and predominated over leucocytes in milk. In colostrum, these epithelial cells (9 to 15 μm) showed weakly positive membrane, sc, contained cytoplasmic SC and had a limited capacity for in vitro proliferation. Ten per cent of epithelial cells contained intracytroplasmic IgA. In milk, the epithelial cells were larger (15 to 40 μm) with a higher expression of both membrane and intracytoplasmic sc; 66 per cent of these cells expressed intracytoplasmic IgA. These data showed that the capacity of mammary epithelium to process IgA to secretory IgA was complete at the end of mammary gland organisation, and established that the epithelial cells of milk contribute to the transfer of IgA to neonates.     

Histochemistry of sialoglycoconjugates in goat submandibular glands

The functional properties of sialic acids appear to be manifold. Therefore, they are considered as essential components of saliva. In this study, the localization of sialoglycoconjugates in the submandibular glands of Japanese miniature (Shiba) goat was examined by light and electron microscopic histochemical methods. The submandibular glands exhibited a large amount of sialic acids. Additionally, sialic acids with O-acetyl substitutions were detectable in the mucous acinar cells and serous demilunar cells. According to lectin histochemical methods, the mucous and serous cells mainly contained the Siaα2-6Gal/GalNAc sequence. These sialoglycoconjugates generated by the submandibular glands may specifically participate in the maintenance of the viscoelastic properties of saliva, protection of oral tissues and prevention of pathogenic microbial attacks. Therefore, our results suggest that they are essential components of saliva to maintain oral health.