小鼠细粒棘球蚴不育囊的超微结构观察

用透射电镜观察了小鼠细粒棘球蚴不育囊的超微结构。其囊壁由角皮层和生发膜构成,角度层含有纤维基质和不规则形颗粒,生发膜又可分皮层区和细胞区。在皮层区基部见到线粒体,微毛间见到“吞饮泡”样质膜凹陷;在细胞区主要有皮层细胞、肌细胞、含糖原细胞等,在有的含糖原细胞中还见到“核仁管系统。”     

细粒棘球绦虫和多房棘球绦虫皮层的扫描电镜和透射电镜观察

扫描电镜显示细粒和多房棘球绦虫的体表外观有许多沟纹皱褶,孕节的皱褶如多层次的环纹,其后端有一深的凹陷。二种成虫体表布满微毛,头节吻突区的微毛呈细长状,其它体节的微毛呈园锥形。二种原头节皮层的微毛与成虫相似,但原头节后端的微毛呈结节状,表明发育未完善。透射电镜显示二种成虫皮层结构由顶端胞质区、表肌区和实质区等三部分组成。皮层顶端胞质区连成一片,没有核和细胞界限,故此说明皮层是一合胞体(syncytium)。微毛是皮层顶端胞质向外呈棘状突起的部分,它由皮层外缘的外质膜包住,故微毛属于细胞内的成份,具有细胞活性。微毛由顶端的锥帽和后端的基部组成,二者之间有基板相隔。顶端的锥帽含整齐的微管。基部富含微丝。肌肉分层不明显,肌细胞不具横纹,肌原纤维具有横纹。实质区主要由疏松的纤维组成网络状,内含许多的核周体,皮层细胞核见于核周体内。此外尚有焰细胞、成石灰小体和线粒体等结构。     

人体细粒棘球蚴的超微结构

透射电镜下角质层呈板层状结构;生发层见较多微毛、皮层和皮层细胞等;并观察到生发层近内侧缘的巨大囊泡、附于内侧缘的电子致密颗粒、位于皮层细胞区的类似神经髓鞘样结构和变性的生发层。扫描电镜观察原头节大多为内陷型,体表无微毛,遍布细小皮孔,顶端见盘状凹陷孔,后端亦微陷,常见蒂外突。少数为外翻型,外观分四部分:顶突有两排头钩,微毛呈细长圆柱状:中部体表见四个吸盘及刀状微毛;后部则见较多细条状或不规则形质膜突起,或遍布细小圆柱状突起;蒂部与内陷型相似。另可见介于两者之间、头节部分外翻的原头节。     

小鼠腹腔继发性细粒棘球蚴的透射电镜观察

本文用透射电镜观察了感染2个月、3个月和6个月的小鼠腹腔继发性细粒棘球蚴。重点描述了6个月的细粒棘球蚴囊壁的超微结构。在生发膜皮层区基部见到线粒体;微毛间见到“吞饮泡”样质膜凹陷,推测细粒棘球蚴生发膜的皮层区不仅是一个简单的物理屏障,而且很可能也是一个复杂的生理、生化屏障。     

猪囊尾蚴的超微结构观察

应用透射电镜观察了取自猪体和人体的猪囊尾蚴颈部和囊壁的形态结构特征。其基本结构为皮层、间质层和实质区。皮层表面密布微毛，内面是基质区，含光面内质网，大量囊泡和圆形空泡，并有数量不等的呈哑铃状的棒状器。线粒体多分布在基质区的近基膜处。皮层以基膜与间质分开。间质层为网状纤维样，并形成分支深入实质区，起支架作用。肌组织位于间质层中，外层为环肌束，内层为纵肌束，间质层向内为实质区，有实质细胞、皮层细胞、成肌细胞及成石灰颗粒细胞。排泄系统中除不同孔径的排泄管外，可见３～５成群的焰细胞与毛细管相通。神经系统中有神经索。     

青海高原不同源原头蚴感染小鼠后继发性棘球蚴的超微结构观察

用透射电镜观察了青海高原藏羊和牦牛源原头蚴接种小鼠后继发性细粒棘球蚴的超微结构。二源继发性棘球蚴囊壁结构相同，由角质层和生发膜构成。角质层由纤维物质和不规则形颗粒形成层状结构，但近生发膜处藏羊源的结构致密，牦牛源的则较为疏松。生发膜可分为皮层区和细胞区。皮层区外缘的微毛藏羊源多而短粗，牦牛源的则呈细长，与各自原发性棘球蚴相同，提示微毛的形态结构稳定，不随宿主不同而改变；牦牛源皮层区基部可见线粒体和大量糖原，提示该区有活跃的生理生化代谢功能。细胞区由皮层细胞和其它成分构成，皮层细胞内细胞器丰富，线粒体形态藏羊源的与原发性相同，牦牛源的则与原发性的存在差异，提示牦牛源棘球蚴线粒体的形态结构不稳定，易受不同宿主的影响。皮层细胞胞质的近囊腔处存在巨大的囊泡，囊壁多为单层。内缘附有线粒体或异染色质样物质，可能与后期子囊的形成有关。本文结果提示该地区可能存在不同的细粒棘球绦虫虫株。     

干芜散对囊尾蚴作用的组织病理学观察

应用中药干芜散治疗囊虫病131例中,对服药1年以上的患者摘除残存的皮下结节做病理观察,部分呈纤维化,虫体消失;部分囊壁增厚,囊液浓缩,虫体呈不同程度损害,虫体头颈部有黑色颗粒沉淀。电镜观察见体壁外层微毛减少或消失;肌纤维稀疏紊乱;实质细胞内出现空泡,核破损;线粒体减少;焰细胞内部结构消失等变化。显示干芜散对囊虫各层结构有显著的损伤作用。     

三例肺细粒棘球蚴的超微结构观察

对3例肺细粒棘球绦虫病病人肺内取出的棘球蚴进行了电镜观察,扫描电镜观察结果:棘球蚴胚层腔面和角皮层外侧面有大小不一、呈圆形、椭圆形的囊泡,其上复盖着粗细不等的细丝。在胚层腔面间隔一定的距离,见边缘整齐的裂隙状凹陷。透射电镜观察结果:棘球蚴胚层细胞腔面有许多长而粗、呈指状、排列整齐的微绒毛,微绒毛为四层膜性结构。微绒毛下的致密带内见许多小泡、微管和少量微丝。胞质内见许多线粒体、粗面内质网、游离核蛋白体、少量糖原、高尔基体和平滑肌。并见两种不同形态组织结构的原生质体。对上述观察结果的生物学意义进行了讨论。     

卫氏并殖吸虫后尾蚴的透射电镜观察

应用透射电镜首次观察了卫氏并殖吸虫后尾蚴的超微结构。虫体由体被、实质组织、肠腔及排泄囊所构成。体被由皮层、肌层、皮层细胞组成。皮层为一合体层,包括外质膜、皮层细胞质和基质膜。皮层表面见许多指状突起,突起有多级分枝。皮层基质内有皮棘,其根部位于基质膜,顶端突出于皮层表面但被外质膜覆盖,横切面上可见网格样结晶,基质内遍布球形、杆状两型分泌小体。皮层细胞位于肌层深部,细胞核位于其内,浆内可见两型特征性分泌小体,皮层细胞发生多条胞质小管穿过肌层及基底膜与皮层相连。结果提示皮层是后尾蚴吸收营养物质的主要部位。     

细粒棘球绦虫虫卵的光镜和电镜观察

应用光镜和电镜技术对细粒棘球绦虫虫卵进行了观察，结果表明细粒棘球绦虫虫卵发育经６个时期：受精卵细胞；胚细胞团；早期虫卵；前期虫卵；未成熟虫卵和成熟虫卵。虫卵壳膜由５层构成：卵壳层；卵黄膜；胚膜；钩蚴膜和颗粒层。六钩蚴分为纤维区和代谢区，前者含有网状和条索状纤维物质，不含细胞成分；后者具有生发细胞、体细胞等，并对各自的形态特点和生理意义进行了讨论。     

ULTRASTRUCTURAL OBSERVATIONS ON THE FORMATION AND METABOLISM OF CALCAREOUS CORPUSCLES IN CYSTICERCUS CELLULOSAE

目的：在超微结构水平研究猪囊尾蚴石灰小体的形成和代谢。方法：透射电镜。结果：石灰小体的形成可分成两个阶段：细胞内形成阶段和细胞外代谢阶段。石灰小体是在一种细胞内形成的，我们称为成石灰小体细胞。在形成的早期，石灰小体以分泌颗粒的形式出现在细胞内。随着石灰小体的发育，小体呈珠粒和板层样。此时，成石灰小体细胞胀大且细胞器消失。最后，小体聚集成致密黑色背景的颗粒，而成石灰小体细胞的核和细胞器全部消失。在一个成熟的成石灰小体细胞内有１－３或１０－２０个石灰小体。然后，小体释放到实质组织，随着代谢的消耗逐渐呈同心圆样的板层结构和空泡结构。结论：石灰小体是在一种细胞内形成，在实质组织的代谢过程中被消耗。     

猪囊尾蚴石灰小体形成和代谢的超微结构观察

目的：在超微结构水平研究猪囊尾蚴石灰小体的形成和代谢。方法：透射电镜。结果：石灰小体的形成可分成两个阶段：细胞内形成阶段和细胞外代谢阶段。石灰小体是在一种细胞内形成的,我们称为成石灰小体细胞。在形成的早期,石灰小体以分泌颗粒的形式出现在细胞内。随着石灰小体的发育,小体呈珠粒和板层样。此时,成石灰小体细胞胀大且细胞器消失。最后,小体聚集成致密黑色背景的颗粒,而成石灰小体细胞的核和细胞器全部消失。在一个成熟的成石灰小体细胞内有１－３或１０－２０个石灰小体。然后,小体释放到实质组织,随着代谢的消耗逐渐呈同心圆样的板层结构和空泡结构。结论：石灰小体是在一种细胞内形成,在实质组织的代谢过程中被消耗。     

曼氏迭宫绦虫裂头蚴超微结构的观察

取黑斑蛙肌肉内的曼氏迭宫绦虫裂头蚴,分别切取新鲜头颈部片段5～7个,经漂洗、固定、脱水、浸透、包埋、切片及染色处理后,透射电镜观察裂头蚴的超微结构。可见裂头蚴的体壁由皮层和实质区组成。微毛位于皮层的外表面,呈尖棘状。基质区内有许多形态各异的颗粒状分泌小体、囊泡、内质网和线粒体,其中线粒体多位于近基膜处。实质区有表层肌、皮层细胞、实质细胞、成石灰小体细胞和排泄系统等分布,并可见皮层细胞形成的胞质连接小管通过基膜伸向基质区。     

Preparation and characterization of submitochondrial fractions from adrenal cells

A method for preparing submitochondrial fractions from adrenocortical cells was developed by adapting a procedure that has been successful with yeast mitochondria. The method is based upon osmotic swelling, sonication and centrifugation in sucrose. The preparation yields highly purified fractions of outer membrane, intermembrane space, inner membrane and a less purified fraction of matrix. Recoveries are good so that 10(7) cells yield approximately 170 micrograms of inner membrane protein and 12 micrograms of outer membrane protein. Electron microscopy shows that the outer membrane fraction consists of vesicles (0.2-0.6 micron diameter) while inner membrane appears as densely packed sheets of membranous material. Two-dimensional polyacrylamide gels (isoelectric focusing followed by electrophoresis) of all the fractions give highly reproducible patterns of protein spots with Coomassie staining. Steroidogenic proteins were found only in inner membrane fractions which were shown to contain cytochrome P-450 C27 side-chain cleavage and P-450 11 beta-hydroxylase together with adrenodoxin and adrenodoxin reductase. Inner membrane catalyzes side-chain cleavage of cholesterol (conversions to pregnenolone) and 11 beta-hydroxylation (DOC----corticosterone) when substrate and NADPH are added. The preparation yields highly purified submitochondrial fractions from Y-1 mouse adrenal tumor cells and from porcine and bovine adrenocortical mitochondria. The method has the virtue of yielding highly purified intermembrane fluid which is not true of other methods for fractionation of adrenal mitochondria. The procedure also yields cleaner preparations of the two membranes than two other published methods currently used to prepare submitochondrial fractions from adrenocortical cells.     

Ultrastructural localization of major hydatid fluid antigens in brood capsules and protoscoleces of Echinococcus granulosus of human origin

Monospecific rabbit antisera obtained through experimental immunization with previously purified proteins were used in the ultrastructural localization of two hydatid fluid antigens, in brood capsules and protoscoleces of Echinococcus granulosus of human origin. The antigen-antibody reaction was revealed by a colloidal gold based method. Reaction was evident in the connective region of the germinal membrane and in the parenchyma of the protoscoleces. Both antigen 5 and antigen B were located in the interstitial material between the parenchymal cells and precisely associated with disorganized areas. The brood capsule wall and the brood capsule contents, the tegument of the protoscoleces, the parenchymal cells, the muscle cells, the calcareous corpuscles and the hooks did not contain antigen 5 or antigen B. Label was not observed in the lumen of the collecting ducts or in the flame cells, although antigen 5 was evident in the periluminal cytoplasm. The origin of the antigens and their release are discussed.     

Three Types of Gap Junctions Interconnecting Intestinal Epithelial Cells Visualized by Freeze-Etching

Gap junctions are specialized membrane regions that seem to mediate intercellular communication. They appear to contain closely packed arrays of equally sized particles all of which, upon freeze-cleaving, remain attached to one membrane leaflet and not to the other. One gap junction cleavage face, therefore, always exhibits a closely packed array of particles, while the other features a corresponding array of pits. By using these morphological criteria, we have been able to distinguish three different types of gap junctions interlinking adjacent epithelial cells of the small intestine. All three types may be found in close proximity to each other, and in all cases, the particles remain attached to the cleavage face of the cytoplasmic membrane leaflet (A-face). The most frequently encountered type-I gap junctions, which have already been observed in many other tissues, possess 8- to 9-nm (80- to 90-A) particles with a center-to-center spacing of 9-10 nm (90-100 A) when packed in a hexagonal lattice. Type-II gap junctions are always found in close association with type-I junctions. They can be distinguished from the type-I junctions by the greater size [10-11 nm (100-110 A) in diameter] and the greater spacing (190-200 A) of their hexagonally arrayed particles. In contrast, the particles of the type-III gap junctions are arranged in very small rectilinear arrays with a spacing of only 6-8 nm (60-80 A). Gap junctions may be involved in the control of intercellular flow of different types of regulatory molecules.     

Ultrastructural alterations in the mitochondrial membranes of ischemic myocardium as revealed by freeze-fracture technique

Mitochondrial membranes of ischemic myocardium were studied with freeze-fracture electron microscopy. Four fracture faces, two each from inner and outer membranes, were exposed. The protoplasmic leaflet or P face contained more intramembranous (IM) particles per μm² than the exoplasmic or E face of the same membrane. Mitochondria became swollen after coronary artery occlusion. The density of IM particles was more reduced on the outer membrane than on the inner membrane of mitochondria examined from myocardium ischemic for 45 min. Aggregation of IM particles was prominent in the tissue reperfused after 45 min of ischemia. Upon progression of ischemia the density of IM particles on both outer and inner membranes was reduced approximately by 50% in mitochondria from myocardium rendered ischemic for 2 and 24 h. More areas of the lipid bilayer which lacked IM particles were exposed in mitochondria examined from myocardium ischemic for 24 h and showed several successive undelineated fracture planes. These findings suggest that myocardial ischemia induces alterations in the lipid fluidity and the distribution pattern of IM particles of the mitochondrial membranes.     

Membrane structure in ultrarapidly frozen, unpretreated, freeze-fractured myocardium

Ultrarapid freezing has been applied to monitor the structure of the freeze-fractured myocardial sarcolemma. Our two goals were to demonstrate that large areas of membrane can be preserved free of visible ice crystal damage and, thus, be amenable to quantitative analysis and to compare the structure of directly frozen myocardial membranes with conventionally prepared tissue. The E face was most affected by lack of chemical pretreatment. First, our laboratory reported an increase in E face particle density from 379 +/- 30/micron 2 in conventional fixed tissue to 489 +/- 18/micron 2 in unpretreated tissue. Discrete arrays of 12-15 nm particles on the E face were a striking feature of the unfixed sarcolemma. However, P face intramembrane particle (IMP) density remained unchanged from previous estimates in fixed tissue. Specialized regions of the sarcolemma were enhanced in ultrarapidly frozen tissue. Particle domains of the adherens junctions were very prominent in forming a cap alongside the gap junctions. Both the P and E faces of the gap junctions were highly ordered into hexagonal arrays. Caveolae in the membrane were infrequent in both P and E faces.     

Gap junctions in thyroid epithelium of the rat.

Gap junctions were observed on the lateral plasma membrane of the typical thyroid epithelial cell in freeze-fracture preparations of rat thyroid gland. The gap junctions were 0.1 to 0.4 mum in diameter and were composed of closely packed, approximately 80 nm particles. They were located from 1 to 6 mum from the apical surface of the cell.     

Dynamic features of luteal secretory granules: ultrastructural changes during the course of pregnancy in the cow

The ultrastructure of large and small cells from corpora lutea of pregnant cows (days 45-280) were evaluated by electron microscopy. The distinguishing features of small cells (10-15 micron in diameter) included stacks of rough endoplasmic reticulum, whorls of smooth endoplasmic reticulum, elongated mitochondria containing crystalline-like inclusions, and cytoplasmic lipid droplets. The large cells (20-50 micron in diameter) contained numerous mitochondria packed tightly together (no elongated structures), an abundance of smooth endoplasmic reticulum (no whorls), and a large number of membrane-bound secretory granules (150-300 nm in diameter). These granules appeared to be packaged in the Golgi, accumulated at a paranuclear region, and migrated as a group to the cell membrane where they were exocytosed. These granules were first observed on day 45 and increased in number to reach a peak around day 200. Lipid droplets became a common cytoplasmic inclusion in the large cells during the third trimester of pregnancy. In addition, during this stage, an electron-dense substance began to accumulate in the mitochondria to such an extent as to occlude the cristae. These mitochondria looked like large (500-1800 nm) membrane-bound granules; however, they did not undergo exocytosis. Their appearance in large cells during the last 3 months of pregnancy may reflect a change in steroid metabolism. Thus, there are two morphologically distinct cell types throughout pregnancy in the cow. The large cell containing the secretory granules underwent what appeared to be a progressive state of apparent deterioration with advancing pregnancy. The morphology of the small cell did not undergo such a dynamic change. No morphological evidence was observed that would support a transition state between the two cell types.