不同动物肥大细胞光镜的结构观察

研究不同种间肥大细胞的异同,为减轻排异反应提供了一定的理论依据。实验用甲醛固定,甲苯胺蓝染色。实验结果显示不同种的肥大细胞形态学结构不尽相同。禽类的肥大细胞与哺乳动物的相似,呈圆形、卵圆形,胞浆内含丰富的异染颗粒是其最显著的形态学特征。牛羊等的肥大细胞在低倍镜下形态多样,呈长梭形、椭圆形、不规则形,有的细胞表面可见细胞突起。     

褐家鼠消化道嗜银细胞的分布及形态学观察

应用Grimelius银染法观察了褐家鼠Arattus norvegicus消化道嗜银细胞的分布密度及形态.结果 显示,在褐家鼠的消化道除食管未见嗜银细胞外,其它部位均有嗜银细胞的分布,其分布密度为胃贲门部最高,回肠部最低.嗜银细胞多分布于消化道粘膜上皮细胞之间或腺泡上皮之间,有时可见于上皮基部和固有膜内.嗜银细胞形态多样,主要以锥体形为主,其次还有圆形、梭形和椭圆形.根据其嗜银细胞形态,认为褐家鼠消化道内嗜银细胞具有内、外分泌、旁分泌3种功能.     

黑龙江草蜥消化道5-羟色胺免疫活性内分泌细胞的分布与形态学观察

应用5-HT抗血清,以ABC(avidin-biotin-peroxidase complex)免疫组织化学方法,对黑龙江草蜥(Takydromus amurensis)消化道内5-HT免疫反应阳性内分泌细胞的分布及形态进行了观察。结果显示：5-HT阳性细胞从食管到直肠的消化道各段均有分布。细胞分布密度呈波浪式,食管、胃幽门部和回肠是其细胞分布密度的高峰。5-HT阳性细胞的形态呈圆形、椭圆形、锥体形、梭形等,其中以圆形和椭圆形为主;广泛分布于上皮基部、上皮细胞之间、腺泡上皮及腺泡之间,有时可见于固有膜内。因此作者认为5-HT阳性细胞具有内、外、旁分泌三种作用途径并且它的密度分布可能与其食性、生活环境等有关。     

蛇岛蝮蛇消化道嗜银细胞的分布及形态学观察

应用Grimelius银染法对蛇岛蝮蛇Gloydius shedaoensis 消化道嗜银细胞的分布密度及形态进行研究.结果 表明,蛇岛蝮蛇的消化道中嗜银细胞分布广泛,见于其全长,主要分布于上皮细胞基部、上皮细胞之间、腺泡上皮细胞之间,也有少量位于固有膜内;胃贲门是嗜银细胞分布密度的高峰,胃体次之,食管分布密度最低;嗜银细胞形态多样,主要有锥体形、梭形、圆形和椭圆形,具有内、外分泌两种功能.     

红腹锦鸡胃肠道内分泌细胞的免疫组织化学定位

应用ABC免疫组织化学方法,对红腹锦鸡(Chrysolophus pictus)胃肠道5-羟色胺(5-hydroxtryptamine,5-HT)、胃泌素(gastfin,GAS)、生长抑素(somatostatin,ss)3种内分泌细胞的分布密度和形态进行了观察.结果显示,5-HT细胞在空肠和直肠分布密度最高,回肠和盲肠次之,十二指肠较少,腺胃和肌胃最少;GAS细胞在十二指肠和直肠分布密度最高,其次是空肠和盲肠,腺胃部最低,肌胃则呈免疫阴性;SS细胞数量较少,在直肠、盲肠处分布密度相对高,其次是十二指肠和空肠,腺胃部最低,肌胃则呈免疫阴性.3种内分泌细胞的形态多样,有圆形、椭圆形、锥体形、杆状和不规则形,其中以圆形、椭圆形为主.细胞分布于固有膜、黏膜上皮细胞基部、黏膜上皮细胞之间、腺泡上皮细胞基部或腺泡上皮细胞之间.红腹锦鸡胃肠道内分泌细胞的形态与其内、外分泌功能是相适应的.     

长鬣蜥胃肠道5-羟色胺细胞的免疫组织化学定位

研究长鬣蜥消化道内含有的5一羟色胺（5-HT）内分泌细胞的位置和形态,采用ABC（avidin—biotin—peroxidase complex）免疫组织化学法,应用5-HT特异性抗血清,对其消化道内的5-HT细胞进行免疫化学定位。结果：5-HT细胞从胃部到直肠的胃肠道各段均有分布,细胞密度分布以胃部最高,十二指肠次之,回肠最低。5-HT细胞的形态呈圆形、椭圆形和锥体形等,其中胃体部和直肠部以圆形和椭圆形为主,小肠部以锥体形为主;5-HT细胞广泛分布于上皮基部、上皮细胞之间、腺泡上皮及腺泡之间,有时可见于固有膜内。结论：5-HT细胞的密度分布与其食性、食物组成和生活环境有关,5-HT细胞的形态与其内、外分泌是相适应的。     

意大利工蜂咽下腺结构观察

通过研究意大利蜜蜂Apis mellifera工蜂咽下腺的结构及形态,为蜜蜂形态学和蜜蜂生理学以及王浆分泌生理提供新知识采用光学显微镜、扫描电镜、HE染色石蜡切片和透射电镜,从形态学和细胞学水平对意大利工蜂咽下腺的结构和功能做了详尽探究和分析.意大利工蜂咽下腺由多个卵圆形腺泡组成,每个腺泡的直径约为120×180 μm,腺泡之间有微气管相连,腺泡外侧有神经细胞,神经细胞的胞体直径约为12μm.每个腺泡是由多细胞构成,最外层有0.1 ～0.2 μm的结缔组织膜,内部有壁细胞、酶原细胞和王浆分泌细胞,其中王浆分泌细胞分布较多,细胞直径约为16 ～ 18 μm,细胞核直径约为6μm. 由咽下腺的形态结构和细胞类型推断,意大利工蜂咽下腺主要分泌王浆,也具有分泌消化酶的功能,同时了解到分泌消化酶和王浆的途径.     

虎斑颈槽蛇消化道5-羟色胺免疫活性内分泌细胞的分布与形态学观察

用免疫组织化学ABC(avidin-biotin-peroxidase complex)法,对虎斑颈槽蛇Rhabdophis tigrinus 5-HT免疫反应阳性内分泌细胞的分布及形态学进行了观察.结果 表明,5-HT阳性细胞从食管到直肠的消化道各段均有分布.细胞密度分布呈"N"型,胃体最高,胃幽门部和胃贲门部次之,空肠最少.5-HT阳性细胞的形态多样,其中贲门和胃以圆形或椭圆形为主,肠道(除直肠)则以锥形为主;广泛分布于上皮基部、上皮细胞之间、腺泡上皮及腺泡之间,有时可见于固有膜内.     

中华绒螯蟹肠道内间质样细胞的显微和超微结构观察

目的探究中华绒螯蟹(Eriocher sinens is)肠道中是否存在间质样细胞。方法通过对中华绒螯蟹中肠和后肠进行全层铺片和肠cajal间质细胞(interstitial cells of cajal,ICC)特殊染色法碘化锌-锇酸(zinc iodide-osmium,ZIO)染色,并结合后肠透射电镜观察中华绒螯蟹后肠ICC样细胞分布及形态。结果光镜检查结果显示:中华绒螯蟹间质样细胞常分布在中肠和后肠的黏膜下层。这些细胞形态相似,多为圆形或卵圆形,胞体直径约为10μm左右,呈灰黑色,常成群呈块状或片状分布,在后肠中的分布更为密集。电镜检测结果显示:这些细胞分布于黏膜下层、肌层与肌层之间和肌肉束边缘。后肠中间质样细胞多为梭形及纺锤形,也有不规则型,常有两个或两个以上突起,与邻近的细胞连接方式多为缝隙连接。此外,本研究还在后肠肠道固有膜层、肌层间和黏膜下层发现了大量颗粒细胞的分布。结论本研究通过传统的特异性ZIO染色和超微形态的观察初步发现中华绒螯蟹肠道内有ICC样细胞的分布。     

枕纹锦蛇消化道5-羟色胺免疫活性内分泌细胞的分布与形态学观察

采用ABC免疫组织化学法,应用5—羟色胺(5-HT)特异性抗血清,对枕纹锦蛇(Elaphe dione)消化道内含有的5—HT内分泌细胞进行了免疫组织化学的定位研究和形态学观察。结果显示,5-HT细胞在消化道各部位的分布密度呈倒“V”形,以十二指肠最高,胃贲门部最低。其形态多样,上段(食管、胃)多为圆形和椭圆形,主要分布于上皮基部和腺泡上皮之间;中段(十二指肠、空肠、回肠)以细长锥体形、梭形、圆形为主,主要分布于上皮基部和上皮细胞之间;下段(直肠)为圆形,分布于上皮基部。锥体形细胞常有一个长突起伸入到固有膜或肠腔,行使内或外分泌功能;梭形细胞有两个细长突起,一个指向固有膜,另一个指向肠腔,表明这种细胞可能具有内、外分泌的双重功能。     

Biophysics and Structure of the Patch and the Gigaseal

Interpreting channel behavior in patches requires an understanding of patch structure and dynamics, especially in studies of mechanosensitive channels. High resolution optical studies show that patch formation occurs via blebbing that disrupts normal membrane structure and redistributes in situ components including ion channels. There is a 1-2 μm region of the seal below the patch where proteins are excluded and this may consist of extracted lipids that form the gigaseal. Patch domes often have complex geometries with inhomogeneous stresses due to the membrane-glass adhesion energy (E_a), cytoskeletal forces, and possible lipid subdomains. The resting tension in the patch dome ranges from 1-4 mN/m, a significant fraction of the lytic tension of a bilayer (∼10 mN/m). Thus, all patch experiments are conducted under substantial, and uneven, resting tension that may alter the kinetics of many channels. E_a seems dominated by van der Waals attraction overlaid with a normally repulsive Coulombic force. High ionic strength pipette saline increased E_a and, surprisingly, increased cytoskeletal rigidity in cell-attached patches. Low pH pipette saline also increased E_a and reduced the seal selectivity for cations, presumably by neutralizing the membrane surface charge. The seal is a negatively charged, cation selective, space with a resistance of ∼7 gigohm/μm in 100 mM KCl, and the high resistivity of the space may result from the presence of high viscosity glycoproteins. Patches creep up the pipette over time with voltage independent and voltage dependent components. Voltage-independent creep is expected from the capillary attraction of E_a and the flow of fresh lipids from the cell. Voltage-dependent creep seems to arise from electroosmosis in the seal. Neutralization of negative charges on the seal membrane with low pH decreased the creep rate and reversed the direction of creep at positive pipette potentials.     

Epigenetics and aging: the targets and the marks

'Aging epigenetics' is an emerging field that promises exciting revelations in the near future. Here we focus on the functional and biological significance of the epigenetic alterations that accumulate during aging and are important in tumorigenesis. Paradigmatic examples are provided by the global loss of DNA methylation in aging and cancer and by the promoter hypermethylation of genes with a dual role in tumor suppression and progeria, such as the Werner syndrome (WRN) and lamin A/C genes. Another twist is provided by sirtuins, a family of NAD-dependent deacetylases that act on Lys16 of histone H4, which are emerging as a link between cellular transformation and lifespan.     

Serology and systematics of the Ebenales and the Theales

The systematic position ofthe Ebenaceae, Sapotaceae, Styracaceae, Ochnaceae, Stachyuraceae, Dipterocarpaceae, Clusiaceae and Hypericaceae has been investigated using serological comparisons of sets of antigenic determinants. The results show that the Sytracaceae and Sapotaceae are undoubtedly more closely associated with the Actinidiaeceae and Theaceae, respectively, than with each other. We found no corresponding determinants betnween antigen systems from the Ebenaceae and systems from any other family whose relations to this family have been proposed. As discovered previously, investigations of antigen systems from the Ochnaceae, Dipterocarpaceae, Stachyuraceae, Clusiaceae and Hypericaceae are against the idea of a natural order “Theales” in which these families, or at least some of them, are combined with the Theaceae and Actinidiaceae. This paper completes our previous investigations which largely support a superorder Ericanae sensu Ehrendorfer and Takhtajan. We propose to include the Actinidiaceae and Theaceae in this superorder, assigning them a central position laong with the Sapotaceae and Sytracaeae on one side and the Primulales and Ericales on the other. Another most interesting finding is that there are corresponding determinants between antigen systems from the members of the Ericanae and representatives of the Polemoniaceae and Loasaceae.     

On the structure and dynamics of the complex of the nucleosome and the linker histone

Several different models of the linker histone (LH)–nucleosome complex have been proposed, but none of them has unambiguously revealed the position and binding sites of the LH on the nucleosome. Using Brownian dynamics-based docking together with normal mode analysis of the nucleosome to account for the flexibility of two flanking 10 bp long linker DNAs (L-DNA), we identified binding modes of the H5-LH globular domain (GH5) to the nucleosome. For a wide range of nucleosomal conformations with the L-DNA ends less than 65 Å apart, one dominant binding mode was identified for GH5 and found to be consistent with fluorescence recovery after photobleaching (FRAP) experiments. GH5 binds asymmetrically with respect to the nucleosomal dyad axis, fitting between the nucleosomal DNA and one of the L-DNAs. For greater distances between L-DNA ends, docking of GH5 to the L-DNA that is more restrained and less open becomes favored. These results suggest a selection mechanism by which GH5 preferentially binds one of the L-DNAs and thereby affects DNA dynamics and accessibility and contributes to formation of a particular chromatin fiber structure. The two binding modes identified would, respectively, favor a tight zigzag chromatin structure or a loose solenoid chromatin fiber.     

Baculoviruses and apoptosis: the good, the bad, and the ugly

Since 1991, when a baculovirus was first shown to inhibit apoptosis of its host insect cells, considerable contributions to our knowledge of apoptosis have arisen from the study of these viruses and the anti-apoptotic genes they encode. Baculovirus anti-apoptotic genes include p35, which encodes the most broadly acting caspase inhibitor protein known, and iap (inhibitor of apoptosis) genes, which were the first members of an evolutionarily conserved gene family involved in regulation of apoptosis and cytokinesis in organisms ranging from yeast to humans. Baculoviruses also provide an ideal system to study the effects of an apoptotic response on viral pathogenesis in an animal host. In this review, I discuss a number of interesting recent developments in the areas of apoptotic regulation by baculoviruses and the effects of apoptosis on baculovirus replication and pathogenesis.     

Connections between the globus pallidus and putamen and the hypothalamus and subthalamus

In 16 adult cats with electrolytically destructed external and internal parts of the globus pallidus and in 8 cats with destructed putamen direct strio-pallido-hypothalamic and strio-pallido-subthalamic pathways have been studied. Degeneration of the axonal preterminals and terminals have been examined in preparations treated after Nauta--Gygax, Nauta--Laidlow, Finck--Heimer with simultaneous additional staining of the nuclei with cresyl violet after Kawamura--Niimi. Direct pallido- and putamen-hypothalamic pathways to nuclei of the grey tubercle, posterior and lateral nuclei of the hypothalamus were stated. Direct pathways from the putamen to the subthalamic nucleus have been revealed, however, these pathways are represented in less degree than those of pallido-subthalamic connections. Direct pathways from the external portion of the globus pallidus and putamen to the subthalamic nucleus are more pronounced and represented by greater numbers of projections than those of strio-pallido-hypothalamic origin.     

The Choroid Plexuses and the Barriers Between the Blood and the Cerebrospinal Fluid

1. The fluid homeostasis of the brain depends both on the endothelial blood–brain barrier and on the epithelial blood–cerebrospinal fluid (CSF) barrier located at the choroid plexuses and the outer arachnoid membrane.2. The brain has two fluid environments: the brain interstitial fluid, which surrounds the neurons and glia, and the CSF, which fills the ventricles and external surfaces of the central nervous system.3. CSF acts as a fluid cushion for the brain and as a drainage route for the waste products of cerebral metabolism.4. Recent findings suggest that CSF may also act as a third circulation conveying substances secreted into the CSF rapidly to many brain regions.