氯化镨在小鼠肝脏细胞中形成含镨致密体

本实验给小鼠4次注射氯化镨(总剂量为200mg/kg)后,光镜发现肝细胞呈嗜酸变性或空泡变性,肝细胞与枯否细胞中酸性磷性酶阳性的溶酶体增多。电镜观察到肝细胞出现程度不同的核变形、内质网扩张、糖原缺乏、溶酶体含较多高电子密度微粒。肝细胞与枯否细胞中均出现由高电子密度微粒聚集形成的致密体,应用X射线微区分析术可测到镨特征性能谱峰。     

钐在小鼠肝脏细胞中的动态观察

本实验给小鼠一次静脉注射氯化钐(70mg/kg体重)后15min至48h中的不同间期,应用电镜与X射线微区分析术对钐在肝脏枯否细胞与肝细胞中的运转进行了动态追踪。于15min 至2 h,两种细胞均以胞吞方式摄入含钐微粒,在胞质中形成吞噬体。在吞噬体中,微粒群处于由稀疏至密集的浓缩过程。小吞噬体亦互相融合。这种胞吞作用于枯否细胞极为活跃。于4—24 h,很多枯否细胞胞质充满吞噬体,细胞已经或趋于变性、崩解。肝细胞内的吞噬体则汇集于胆小管周围。于胆小管腔中可见到高电子密度微粒群,表明体内钐可经胆汁途径排出。于48 h,两种肝脏细胞巾仍见钐吞噬体沉积。     

溶酶体膜H^＋—ATP酶的细胞化学观察

本实验在以p-NPP为底物、氯化铈为捕捉剂、Tricine-KOH为缓冲液的中性最适环境中温育大鼠肝组织,进行肝细胞、血窦内皮细胞和枯否氏细胞内溶酶体膜上H~+-ATP酶定位的细胞化学研究。温育反应形成的磷酸铈反应产物电子密度高、颗粒细、分布均匀、非特异性反应产物少、重复性好。对照实验证实,溶酶体膜上的H~+-ATP酶是对哇巴因耐受的,对NEM敏感的囊泡膜H~+-ATP酶。     

补体对枯否细胞吞噬分泌功能的影响

枯否细胞是肝内定居的具有分泌功能的巨噬细胞群,本文综述了十来年中补体对枯否细胞吞噬分泌功能影响的研究成果,提出补体的过度活化可能导致枯否细胞功能失常,进而使内源性感染的可能性增加、介导肝损伤。     

人类肝脏中甲型肝炎抗原的检查

<正> 应用过氧化物酶标记抗体的技术,通过光学显微镜和电子显微镜检查,首次在一位甲型肝炎急性期患者的肝穿刺活检组织中发现了甲型肝炎病毒抗原(HAAG)。在光学显微镜检查下,着色的HAAG呈现出细小的颗粒状反应物,它们全都分布于肝细胞胞浆和窦状内皮细胞的细胞质囊内。超薄切片的电镜术揭示了肝细胞和枯否氏细胞的胞浆囊     

低分子量透明质酸片段通过toll样受体4信号途径激活枯否细胞

高分子量透明质酸（high-molecular-weight hyaluronic acid,HMW-HA）是重要的肝脏基质,分子量高达2×10^6Da以上,可被活性氧分子（reactive oxygen species,ROS）等降解成低分子量透明质酸片段（hyaluronic acid fragments,HA fragments）,后者能被toll样受体4（toll-like receptor4,TLR4）识别并激活免疫细胞诱发炎症反应。基于枯否细胞表达TLR4,推测HA fragments通过激活枯否细胞TLR4信号系统而启动肝脏缺血再灌注损伤。从TLR4基因突变型（C3H／HeJ,TLR4^Mut/Mut）及野生型（C3H／HeN,TLR4^＋/＋）小鼠分离肝脏枯否细胞常规培养,用酶降解及色谱柱分离方法制备HA fragments,观察HMW-HA及HA fragments激活枯否细胞的差异,检测培养上清肿瘤坏死因子-α或白介素-1β水平变化;枯否细胞p38MAPK信号通路的活化;用特异性p38MAPK阻断剂—SB-203580,阻断p38MAPK活化后,观察培养上清中肿瘤坏死因子-α或白介素-1β水平变化。结果显示HA fragments可以促进TLR4^＋/＋枯否细胞分泌促炎因子,不能诱导TLR4^Mut/Mut枯否细胞分泌促炎因子。而HMW-HA既不能促进TLR4^＋/＋枯否细胞也不能促进TLR4^Mut/Mut枯否细胞分泌促炎因子。采用多黏菌素中和脂多糖后,HA fragments促进TLR4^＋/＋枯否细胞分泌促炎因子的能力不变,这一过程伴随p38MAPK信号通路的活化。当运用p38MAPK信号通路的特异性阻断剂SB-203580,抑制p38MAPK活性时,HA fragments促进TLR4^＋/＋枯否细胞分泌促炎因子的能力显著下降。因此与基质组成成分HMW-HA不同,HA fragments可以通过TLR4激活枯否细胞,促进其分泌促炎因子诱发炎症反应,这一过程依赖于p38MAPK的激活。     

白细胞介素-16在脓毒症肝和肺组织中表达的免疫组织化学研究

观察白细胞介素－16（interleukin-16,IL-16)在脓毒症时肝和肺组织中的细胞定位及分布,并探讨其在脓毒症发病中的作用和意义。应用新型敏感的免疫组织化学方法（超敏感－SP法）检测本校近年收集的18例感染、败血症和脓毒症尸检肝和肺组织白细胞介素－16的原位表达,在肝组织中IL－16主要定位于肝窦枯否细胞、单核细胞以及部分中性粒细胞、阳性率达72.3%。肝细胞形态改变主要包括肝窦扩张充血,枯否细胞增生肿胀,肝细胞变性及不同程度的灶性坏死,在肺组织中IL－16定位于肺部质及感染灶内的巨噬细胞,中性粒细胞以及少量淋巴细胞,其阳性率达66.7％。肺组织形态改变主要包括肺泡壁毛细血管扩张充血,间质及肺泡壁内大量炎性细胞浸润,部分肺泡扩张,肺泡壁断裂;可灶性坏死,坏死区肺结构消失,纤维组织增生。同时,观察到IL－16随组织病理变化的加重表达增强的趋势。本研究结果提示IL－16可能在脓毒症所致脏器损害中发挥重要作用。     

东方蝾螈肝脏形态学与组织学观察

对东方蝾螈Synops orientalis的肝脏进行了组织学观察.结果 如下:东方蝾螈肝脏分为5叶,每叶由许多肝小叶组成.中央静脉位于小叶中央,肝细胞排列成肝细胞索(肝板),以中央静脉为中心向周围呈放射状排列.肝细胞索或肝细胞团之间的间隙为形状不规则、大小不等的肝血窦,窦壁由一层内皮细胞构成,间有枯否氏细胞,其核为细长状,有数目不等突起.肝细胞间有狄氏间隙,肝细胞呈多边形,胞核为圆形或卵圆形.肝实质内有大量色素沉着.并将东方蝾螈肝脏和其他动物肝脏进行了比较.     

大鼠肝癌发生过程中转化生长因子-β1的表达及意义

为了进一步探讨转化生长因子-β1在肝癌发生中的作用和意义。本采用免疫组织化学ABC法,对二乙基亚硝胺（DEN）诱发大鼠肝癌发生过程中转化生长因子-β1（Transforming growth factor-β1,TGF-β1）表达情况进行了观察。结果显示;在正常大鼠肝脏,TGF-β1的表达只局限于血窦内皮细胞或枯否细胞,汇管区血管内皮细胞及胆管上皮细胞,肝细胞呈TGF-β1阴性表达,诱癌早期（4-8周）,大鼠肝小叶内除血窦内皮细胞或枯否细胞呈TGF-β1阳性表达外,可见少量散在分布的肝细胞呈TGF-β1阳性表达,阳性肝细胞胞质内可见棕褐色阳性反应颗粒,随着肝癌发展,TGF-β1阳性肝细胞逐渐增多,至诱癌晚期（18周）,癌结节内的大多数肝癌细胞呈TGF-β1阳性表达。本研究显示TGF-β1与肝癌的发生和发展密切相关。至诱癌晚期（18周）,癌结节内的大多数肝癌细胞呈TGF-β1阳性表达,本研究显示TGF-β1与肝癌的发生和发展密切相关。     

中国大鲵肝脏的超微结构

应用透射电镜对中国大鲵的肝脏进行了超微结构研究.观察表明,大鲵肝不具肝小叶,与其他脊椎动物有所不同.肝细胞含有单个卵圆形的核;细胞质内含有粗面内质网、高尔基囊泡、线粒体、糖原颗粒和脂滴等细胞器和内含物.胆小管由两个相邻肝细胞质膜凹陷围成,而肝血窦则由内皮细胞的胞质构成.胆小管腔和窦周隙内浸润许多由肝细胞发出的微绒毛结构.还发现了枯否氏细胞和贮脂细胞.还讨论了中国大鲵肝脏的一般形态结构特点.     

钐在小鼠肝脏细胞中的动态观察

It is generally considered that the rare earth compounds are plasma membrane-impermeable, thus affecting the cells only on their surface. Recently, we found that after repeated injections to mice of large dose of samarium trichloride, a soluble compound of rare earth, samarium aggregates appeared in Kupffer cells and hepatocytes of liver. In this study, we aimed at observing the route by which samarium enters the liver cells and the process of the formation of samarium aggregates. Samarium trichloride was given to Swiss mice at one dose of 70 mg/kg intravenously. Thereafter, at different intervals from 15 min to 48 h after the injection, the samarium in liver was traced dynamically by electron microscopy and X ray microanalysis. From 15 min to 2 h both Kupffer cells and hepatocytes endocytosed samarium-containing particles and formed phagosomes, in which the ingested particles were progressively concentrated. Besides, the small phagosomes fused with each other. Phagocytosis was especially active in Kupffer cells. During the 4 h to 24 h many Kupffer cells were degenerated and broken. In hepatocytes the phagosomes gathered mostly around the bile canaliculi. Groups of highly electron-dense particles were found in the lumen of bile canaliculi, implying the excretion of samarium by bile. At the 48 h, the samarium-containing phagosomies were found still in both kinds of cells in the liver.     

Gilbert 综合征肝活检的超微结构特征*

目的:确定Gilbert综合征患者肝组织的超微结构特征,为Gilbert综合征的诊断和鉴别诊断提供新的方法。方法:按电镜常规进行标本制备,应用透射电镜对20例Gilbert综合征患者肝穿刺活检组织进行超微结构观察。结果:肝细胞可出现巨大线粒体,常含有副晶格样包涵体、较明显的基质致密颗粒。肝细胞常见脂褐素颗粒增多,多分布于毛细胆管周围肝细胞内。可出现较有特征性的色素颗粒,大小不等,卵圆形或不规则形,含有电子致密块状颗粒,与电子密度略低的聚集物以及脂滴互相混杂。这些溶酶体颗粒的基质由细小的、弱嗜锇性的颗粒组成。少数颗粒类似Dubin-Johnson综合征的颗粒。但颗粒较小,缺少致密核芯结构。结论:特征性的含粗大电子致密物的溶酶体对Gilbert综合征的诊断有重要参考价值。     

Effects of rare earth ions (Tb,Ce, Eu,Dy) on the thermoluminescence characteristics of sol–gel derived and γ‐irradiated SiO2 nanoparticles

Highly pure SiO₂ and SiO₂:RE nanoparticles were synthesized by the sol–gel method. The morphological, structural and optical properties of the nanoparticles were characterized by X‐ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). XRD results indicate that all the samples studied were free from impurities. SEM/TEM results indicate that the samples were well dispersed. Surface characterization of the nanocrystals by Fourier transform infrared spectroscopy has been carried out and the structure of surface‐bound SiO₂ based on spectral analysis is proposed. Thermoluminescence (TL) characteristics were investigated to study the influence of rare earth dopants (Tb, Ce, Eu, Dy) on SiO₂ matrix subjected to 0.5 kG (1 h) γ‐irradiation. Among these rare earth elements, Eu³⁺ was found to be the most efficient dopant for SiO₂ showing maximum thermoluminescence intensity. SiO₂:Eu_0.5 seems to be a promising candidate for use as a TL dosimeter. Copyright © 2013 John Wiley & Sons, Ltd.     

Research of the entry of rare earth elements Eu3+ and La3+ into plant cell

Whether rare earth elements can enter into plant cells remains controversial. This article discusses the ultracellular structural localization of lanthanum (La³⁺) and europium (Eu³⁺) in the intact plant cells fed by rare earth elements Eu³⁺ and La³⁺. Eu-TTA fluorescence analysis of the plasmalemma, cytoplast, and mitochondria showed that Eu³⁺ fluorescence intensities in such structures significantly increased. Eu³⁺ can directly enter or be carried by the artificial ion carrier A23187 into plant cells through the calcium ion (Ca²⁺) channel and then partially resume the synthesis of amaranthin in the Amaranthus caudatus growing in the dark. Locations of rare earth elements La³⁺ and Eu³⁺ in all kinds of components of cytoplasmatic organelles were determined with transmission electron microscope, scanning electron microscope, and energy-dispersive X-ray microanalysis. The results of energy-dispersive X-ray microanalysis indicated that Eu³⁺ and La³⁺ can be absorbed into plant cells and bind to the membranes of protoplasm, chloroplast, mitochondrion, cytoplast, and karyon. These results provide experimental evidence that rare earth elements can be absorbed into plant cells, which would be the basis for interpreting physiological and biochemical effects of rare earth elements on plant cells.     

STRUCTURE AND DEVELOPMENT OF VIRUSES OBSERVED IN THE ELECTRON MICROSCOPE : IV. VIRUSES OF THE RI-APC GROUP

Representative viruses of the RI-APC group were observed with the electron microscope in thin sections of infected HeLa cells. The viral particles varied in density, were approximately 60 mµ in diameter and had a center to center spacing when close packed of about 65 mµ. Many of the less dense particles exhibited an internal body averaging 24 mµ in diameter. It was suggested that within the nucleus the virus differentiated from dense granular and reticular material and formed crystals. Disintegration of the crystals and disruption of the nuclear membrane with release of virus into the cytoplasm appeared to occur at any stage. No evidence to suggest development of the virus in the cytoplasm was obtained. It was possible to deduce the structure of the viral crystal from the electron micrographs. The viral particles are packed in a cubic body—centered lattice. Correlative histochemical observations in the light microscope which are now in progress revealed that the crystals and non-crystalline aggregates of virus were strongly Feulgen-positive.     

Plasmodium falciparum: fine structural changes in the cytoskeletons of infected erythrocytes

Following parasitization by Plasmodium falciparum, numerous changes take place in the host erythrocyte membrane. In this study, we used the technique of whole cell mount electron microscopy to determine if the ultrastructure of the erythrocyte cytoskeleton changed following parasitization with knobby and knobless strains of P. falciparum. Using this technique, a network of spectrin filaments (3-10 X 45-120 nm) branching from electron dense junctions (15-25 nm in diameter), the presumed site of bands 4.1 and actin, were visualized. The overall architecture of normal and parasitized erythrocyte cytoskeletons was the same: however, additional patches (35 to 60 nm in size) and aggregates (30 X 150 nm) of electron dense material were present in parasitized skeletons. The ultrastructure of knobby and knobless cytoskeletons was similar, except knobless skeletons usually did not possess the larger aggregates of material. Antigens associated with the erythrocyte cytoskeleton of cells infected with knobby and knobless strains, but not uninfected cells, were demonstrated by indirect immunofluorescence. Results suggest that antigens, associated with the erythrocyte cytoskeleton, may contribute to perturbations in the host erythrocyte membrane.     

稀土元素对小麦幼苗氮素吸收及其同化的影响

稀土元素浸种能够促进小麦(Triticum aestivum L.)幼苗对NO_3~-的吸收,提高硝酸还原酶活力。这些效应与稀土浓度有关,低浓度有促进作用,高浓度则有抑制作用。稀土元素处理还能促进小麦幼苗体内NO_3~-的同化还原,使硝态氮含量降低,氨基氮含量增加,促进了氮素代谢过程。     

THE USE OF SILVER NITRATE AS A VITAL STAIN, AND ITS DISTRIBUTION IN SEVERAL MAMMALIAN TISSUES AS STUDIED WITH THE ELECTRON MICROSCOPE

After chronic administration of a dilute solution of silver nitrate in drinking water to rats, mice, and guinea pigs, granular deposits of metallic silver were detected in electron micrographs of the kidney, liver, thyroid, and pancreas. The silver deposits were in the form of extremely dense, angular particles with sharp outlines. They varied from aggregates a few microns in diameter down to granules at the limit of resolution of the electron microscope. The principal sites of deposition were (1) basement membranes, especially those of the renal glomeruli, proximal convoluted tubules, and various glands, and those associated with vascular endothelium, and (2) the cytoplasm of fixed and free macrophages. Both in Kupffer cells lining hepatic sinusoids and in the wandering macrophages of other tissues, the silver was segregated in discrete vacuoles. In addition, granular deposits were observed in occasional vesicular structures in the proximal convoluted tubules of the kidney, the hepatic cells, and the pancreatic acinar cell. These structures, in favorable preparations, contained an outer double layered membrane and internal folds similar to those of mitochondria, from which they appear to have been derived. The significance of these findings in heavy metal poisoning and in cellular physiology is briefly discussed.     

Morphology of the liver of the brook lamprey, Lampetra lamottenii before and during infection with the nematode, Truttaedacnitis stelmioides, hepatocytes, sinusoids, and perisinusoidal cells.

Routine light microscopy and transmission and scanning electron microscopy were used to describe and compare the livers of larval lampreys, Lampetra lamottenii before and during infection of the bile ducts by the nematode, Truttaedacnitis stelmioides. The hepatocytes of uninfected animals differ from other lamprey species in that they contain abundant glycogen, smooth endoplasmic reticulum (SER), and lipoprotein indicating that the liver may be involved in glucose metabolism. Infestation of the biliary tree by T. stelmioides coincides with alterations to the hepatocytes. These changes include dilation of the bile canaliculi, smooth endoplasmic reticulum (SER), rough endoplasmic reticulum (RER), and Golgi apparatus, swollen mitochondria in cells showing a high degree of hypertrophy, and an abundance of dense bodies. Following infection, the sinusoidal lumina became dilated and contain a moderate electron-dense precipitate, an abundance of melanomacrophages, lipocytes, and mononuclear cells. There is also a widening of the fenestrae of the sinusoidal endothelium following infection. Many of the changes in hepatocytes and sinusoids following parasite infections closely resemble those observed in hepatocytes in various pathologies and following experimental bile duct ligation and, therefore, are likely a consequence of increased biliary pressure due to bile duct obstruction.