Elimination of large pyroninophilic cells by the action of phytohemagglutinin

Disappearance of medium-sized and large pyroninophilic lymphocytes, adsorbed on the surface of target cells, was shown to take place after the addition of phytohemagglutinin (PHA). After incubation for 45 min in the presence of PHA no cisterns of the granular endoplasmic reticulum could be found in the lymphocytes and the mitochondria were fewer in number. Cells labeled with thymidine-H³ had practically completely disappeared. A population of small lymphocytes with smooth outlines and pale cytoplasm, poor in organelles, and with ribosomes scattered freely in them appeared. After incubation for 24–48 h they were transformed into blast cells, larger cells with a pale nucleus and pale cytoplasm, in which no cisterns of the granular endoplasmic reticulum could be found.     

Fasciola hepatica: disruption of the vitelline cells in vitro by the sulphoxide metabolite of triclabendazole

 The effects of the active sulphoxide metabolite of the fasciolicide triclabendazole (Fasinex, Ciba-Geigy) on the vitelline cells of Fasciola hepatica were determined in vitro by transmission electron microscopy using both intact flukes and tissue-slice material. At a triclabendazole concentration of 15 μg/ml the vitelline cells of intact flukes showed ultrastructural changes only after prolonged incubation periods (12–24 h). The changes observed were a swelling of the granular endoplasmic reticulum (GER) cisternae with decreased ribosomal covering in the intermediate-type cells and condensation of chromatin and disappearance of the nucleolus in the nucleus of the stem cell. Similar changes were evident more quickly (by 6 h) in whole flukes treated at the higher concentration of 50 μg/ml. The shell globule clusters were loosely packed in the intermediate type-2 cells, and the number of intermediate type-1 cells declined with more prolonged incubation. Disruption of the nurse-cell cytoplasm was also observed from 12 h onwards. After only 6 h incubation of tissue-slice material at 50 μg/ml, intermediate type-1 cells were absent, shell globule clusters in mature cells were loosely packed and the nurse-cell cytoplasm was badly disrupted. By 12 h the vitelline cells were vacuolated and grossly abnormal. The results are discussed in relation to postulated actions of triclabendazole against the microtubule component of the cytoskeleton and against protein synthesis in the fluke. Received: 15 August 1995 / Accepted: 24 October 1995     

Ultrastructural study of liver cell damage induced by ricin.

Experiments were carried out on female albino (Wistar) rats to establish ricin's liver damaging effect. In accordance with the data in the literature it seems that: 1. 2 microg/kg i.p. ricin (investigated 24 h later of its administration) has a detectable hepatotoxic effect; i.e. electron density changes of cells and swelling of mitochondria. These findings correspond to the common and first ultrastructural signs of liver cell damage. This result was further strengthened by the fact that serum ALT and AST values were significantly elevated compared to the control value. 2. The next steps of ricin's damaging effect have been detected at 10 microg/kg i.p. dose,--namely: Effect on smooth endoplasmic reticulum: in its place there is a loose, foam-structured unidentified material,--while in the granulated endoplasmic reticulum the number of ribosomes decreased, similarly to the glycogen granules. 3. 200 microg/kg i.p. ricin caused a severe liver-cell damage. The mitochondria showed early degenerative signs,--and both endoplasmic reticulums were further damaged. The most significant feature is the complete lack of ribosomes in the tubular structure of the granulated endoplasmic reticulum. This latter finding enlights the known inhibitory effect of ricin on protein synthesis. The serum enzyme-levels remained in the pathological range. No early sign of enzyme (Cytochrome P450,) induction could be observed.     

Comparative study of ultrastructure of immune and normal lymphocytes treated with phytohemagglutinin

Immune lymphocytes adsorbed on the surface of target cells during the first 3 h of combined incubation are characterized by the presence of an electron-optically dense matrix and by abundance of mitochondria and lipids; the small lymphocytes contain freely scattered ribosomes, which in medium lymphocytes are organized into polysomes and form separate cisterns of the granular endoplatmic reticulum in large lymphocytes, evidence of active protein synthesis by these cells. Cells of the plasma type also were found. Cells treated with phytohemagglutinin for 1 h consisted of a uniform population of small lymphocytes of identical size, with pale cytoplasm containing free ribosomes and single mitochondria. The proportion of medium lymphocytes and blast cells increased with an increase in the period of incubation. These were cells with pale cytoplasm and with freely scattered polysomes, in which a developed granular endoplasmic reticulum was never found. The presence of two types of cells whose ultrastructure reflects their functional characteristics is discussed.     

The pathobiology of salivary gland

Summary Fragments of rat submandibular gland (organoids) which maintained the topological organization of the parent tissue were cultured in a three-dimensional collagen gel matrix for up to 30 days. At 48 h, vigorous peripheral outgrowth had occurred around each organoid. This was accompanied by central necrosis and the bridging of adjacent organoids. By day 5, large cyst-like spaces occupied the centre of many organoids. Bromodeoxyuridine labelling indicated that a considerable proportion of the lining cells were proliferating. Organoid growth peaked at between 5 and 10 days. Thereafter, the number of viable colonies and proliferating cells declined. Addition of isoproterenol after 24 h culture resulted in marked morphological alterations, with earlier and more prolific outgrowth and a greater tendency for organoids to flatten and grow out over the surface of the gel with squamous differentiation. Ultrastructurally, nuclear and cytoplasmic features of isoproterenol-treated and untreated cultures were similar. The secretory granules and extensive rough endoplasmic reticulum of terminal tubule cells, evident in organoids immediately after isolation, were infrequent after 24 h and absent by 48 h. Similar alterations occurred in the few acinar cells, so by 5 days the cultures were composed entirely of a uniform population of primitive, dedifferentiated cells. Further uses of this culture systems will include the study of diseases and disorders of the salivary glands as well as normal growth and differentiation pathways.     

Bromobenzene-induced zonal necrosis in the hepatic acinus

The time course and acinar distribution of bromobenzene-induced hepatic necrosis was studied in the rat. Cellular damage, lipid infiltration, and changes in glycogen deposits were investigated by light microscopy 6, 16, 24, and 48 hr after bromobenzene (BZ) administration. Concomitantly, ultrastructural changes were followed by electron microscopy in each zone of the acinus. To insure accurate orientation in acinar zones, a double embedding technique for electron microscopy was used. Acinar zones were localized by light microscopy and subsequently re-embedded for electron microscopy. Zone 3 was the site of conformational changes in smooth endoplasmic reticulum 6 hr after BZ administration. This condensed, tubular network represented the earliest morphological sign of injury observed by electron microscopy. At 48 hr, cytoplasmic vacuolar degeneration and necrosis were observed in the hepatocytes of acinar zone 3. While no necrosis was observed in the cells of zone 1, other morphological changes occurred. These included progressive lipid accumulation, as well as fluctuations in the amount of rough endoplasmic reticulum and free ribosomes. These latter observations suggested a possible link between protein manufacture and survival of the zone 1 cells. These results established that, following bromobenzene administration, necrosis was restricted to zone 3 hepatocytes.     

Cardiac morphologic alterations in acute minoxidil cardiotoxicity in miniature swine

Minoxidil, a vasodilating antihypertensive drug, was given orally at 10 mg/kg daily for 2 days to twelve 25- to 35-kg miniature pigs. Twelve control pigs were also studied. Minoxidil-treated pigs had tachycardia and hypotension and were killed 24 hr after the second dose. Gross examination showed diffuse hemorrhage in left atrial epicardium in all pigs, and also in ventricular epicardium (2 of 12 pigs) and endocardium (3 of 12 pigs). Pale areas of necrosis were observed on incision of the left ventricular papillary muscles in 3 pigs. Light and electron microscopic studies showed acute vascular damage with hemorrhage in the left atrial epicardium. Affected arterioles had endothelial cell swelling and transmural and perivascular accumulations of leukocytes, edema fluid, fibrin clumps, and erythrocytes. The swollen endothelial cells had large, irregularly shaped nuclei with abundant euchromatin; mitotic figures were frequent. The cytoplasm contained numerous polysomes and cisterns of rough endoplasmic reticulum. Fibroblasts adjacent to damaged vessels had edematous cytoplasm and increased amounts of rough endoplasmic reticulum. In the affected left ventricular papillary muscles, necrotic myocytes showed contraction bands, mitochondrial matrical densities, lipid accumulation, initial lysis of I bands, and pyknotic nuclei. The lesions were judged to result from two mechanisms: (1) hemorrhagic lesions from drug-induced vascular injury centered on epicardial and subepicardial arterioles and (2) papillary muscle necrosis from ischemic injury from hypoperfusion during minoxidil-induced tachycardia and hypotension.     

Pulmonary endothelial and bronchiolar epithelial lesions induced by 4-ipomeanol in mice.

The morphogenesis of pulmonary edema and bronchiolar injury induced by the toxic furan, 4-ipomeanol, was studied by combined light and transmission electron microscopy. Weanling male CD-1 mice received 47 mg 4-ipomeanol/kg body weight by intraperitoneal injection and were studied at intervals from 2 to 360 hours after treatment. Interstitial edema associated with damaged endothelial cells was observed as early as 2 hours after treatment. The most severe endothelial damage was observed from 12 to 24 hours after treatment and occurred in association with alveolar edema. Capillary endothelial cell damage was characterized by marked dilation of endoplasmic reticulum and perinuclear envelopes, marked swelling of mitochondria, separation of cytoplasmic processes from other endothelial cells and their basal laminae, and occasional disruptions in the plasmalemma. Endothelial cell lesions in small caliber veins were similar but less pronounced as compared with the alterations observed in capillary endothelium. Minimal changes were present in alveolar epithelial cells. Damage to nonciliated bronchiolar epithelial cells was first observed at 4 hours after injection. The most severe changes in nonciliated cells occurred from 36 to 48 hours after treatment and included swelling of endoplasmic reticulum, necrosis, and sloughing. There was also necrosis and sloughing of ciliated bronchiolar epithelial cells. Endothelial and bronchiolar epithelial repair and resolution of the alveolar edema were complete by 240 hours after treatment. It is concluded that the endothelium lining capillaries and small veins, in addition to the nonciliated bronchiolar epithelial cell, are early targets in the development of 4-ipomeanol toxicity in the mouse and that the endothelial cell injury plays a major role in the development of pulmonary edema in this species. The results further suggest the possibility that pulmonary endothelial cells have the capability of metabolizing xenobiotic compounds such as 4-ipomeanol to form ultimate toxins.     

The fine structure of the epithelium of prostate glands in adult female mastomys erythroleucus Temm.

The prostate glands in adult female Mastomys were studied with the light and the electron microscope. In the light microscopy, each prostatic acinus is lined by a single layer of tall cuboidal secretory epithelial cells which are surrounded by a capsule composed of a few layers of elongated and flattened cells. The acinar secretory epithelial cells show no presence of the supranuclear light areas in their cytoplasm and tend to be more readily stained with toluidine blue in the perinuclear and the upper basal cytoplasm than in the rest cytoplasm. In the electron microscopy, sharply localized pittings are occasionally found on the luminal surface and further the secretory granules which are closely situated to the apical cell surface are recognized. In the supranuclear cytoplasm, several well-developed Golgi apparatuses appear individually and early developing secretory granules are also observed. In the perinuclear and the upper basal cytoplasm the rough endoplasmic reticulum is well developed while in the lower basal cytoplasm the smooth endoplasmic reticulum is conspicuously developed and predominates.     

Effect of cerium on the rat liver: an ultrastructural and biochemical study.

In rats, liver steatosis and necrosis were induced by cerous chloride (CeCl3) and the evolution of these changes was examined. By electron microscopy, 17 hours after CeCl3 treatment, dilation, disorganization and degranulation of the rough endoplasmic reticulum (RER) were noted with an increase in the number and electron density of lysosome-like bodies. In addition, nuclear chromatin showed showed a marked focal electron density, and the nuclear membrane appeared to be interrupted. At 24 hours, the RER was markedly dilated and degranulated, with free ribosomes aggregated in the cytoplasm. The Golgi cisternae appeared to be empty. There was an increase in the number and size of lipid droplets, with depletion of glycogen. At 48 hours, a massive proliferation of smooth endoplasmic reticulum (SER) vesicles occurred. Large lipid droplets were scattered throughout the cytoplasm, while the mitochondria displayed mild changes. By the 8th day, the number of lipid droplets returned to normal; no abnormalities were detected in the other cell organelles. Biochemically, the total hepatic ATP levels fell significantly by the 12th hour, dropping to a minimum by the 48th hour. The liver was gradually depleted of glycogen within the first 48 hours, while hepatic triglycerides increased rapidly, reaching a peak at 96 hours. Exogenous administration of adenine, ATP (adenosine triphosphate), or tryptophan completely prevented CeCl3-induced mortality; hepatic fat accumulation and necrosis were markedly decreased. Glucose, dl-methionine, and choline had no protective effect. It appears that a defect in hepatocellular lipoprotein synthesis and/or release may be responsible for lipid accumulation.     

人胎儿子宫发育的体视学研究

目的探讨人胎儿子宫发育过程细胞核质变化规律。材料与方法利用体视学原理,对 33 例胎龄 14～35 周人胎儿子宫内层及肌层厚度、细胞核平均体积、核浆比、粗面内质网表面积密度等体视学参数进行测算。结果在胎龄 14～25 周期间,胎儿子宫内层随胎龄增长,其组织厚度、细胞核浆比以及粗面内质网表面积密度均无显著变化,细胞核平均体积显著增大。胎龄 26～29 周,内层组织厚度增长迅速,细胞核浆比显著降低,粗面内质网表面积密度迅速增加,细胞核平均体积显著减小,肌层随胎龄增长细胞核浆比逐渐降低,粗面内质网表面积密度显著增加,细胞核平均体积无明显变化。结论胎龄 26～29 周是胎儿子宫发育的重要时期。     

高糖通过环加氧酶2依赖性途径诱导GRP78表达改变

目的： 观察高糖慢性处理对血管内皮细胞内质网应激标志蛋白葡萄糖调节蛋白78（GRP78）表达的影响及其作用机制。方法：培养的HUVECs细胞用含正常糖（5.5 mmol/L）或高糖（30 mmol/L）的培养基处理不同时间后,用MTT法测定细胞存活率,流式细胞仪测定细胞凋亡,Western blotting法测定蛋白表达情况。结果：与相应对照组相比,HUVECs细胞经高糖孵育24-48 h 后,GRP78蛋白表达量先增加后减少;而环加氧酶-2（COX-2）蛋白表达量逐渐增加。COX-2选择性抑制剂尼美舒利与高糖共孵育后,可明显抑制高糖引起的GRP78蛋白表达改变;同时尼美舒利可抑制高糖孵育48 h 后诱导的细胞凋亡。结论：高糖慢性处理可诱导HUVECs细胞GRP78表达先增加后减少,此过程依赖于COX-2蛋白的上调。     

Extraskeletal myxoid chondrosarcoma: a clinicopathological study of six cases]

The clinicopathologic, ultrastructural, and immunohistochemical features of six cases of extraskeletal myxoid chondrosarcoma are described. Light microscopic examination disclosed a lobulated neoplasm consisting of cells that tended to be round or polygonal with plenty of eosinophilic cytoplasm. The tumor cells were arranged in strands and small nests surrounded by abundant myxoid extracellular matrix. Ultrastructurally, these tumor cells displayed the signs of chondroblastic differentiation. The cytoplasm contained numerous rough endoplasmic reticulum, mitochondria and scattered glycogen granules. The intercellular matrix showed amorphous material and electronic dense and fine granules. The tumor cells in all these six cases showed diffuse immunostaining for S-100 protein but were negative for keratin. The data obtained tend to support the chondroblastic origin of this tumor.     

Electron microscopical morphometry of GH producing pituitary adenomas in comparison with normal GH cells

Summary GH producing adenomas of patients with acromegaly (undifferentiated acidophil adenomas and well differentiated GH cell adenomas) were studied at the ultrastructural level and analysed morphometrically by the point counting method. They were compared with identically prepared GH cells of normal pituitaries from patients undergoing surgery for metastasizing cancer of the prostate. In the well differentiated GH cell adenomas significantly more points were counted on nucleoli, unorganized cytoplasm, rough endoplasmic reticulum, immature secretory granules, Golgi areas and on the plasma membranes, than in normal GH cells. Comparison of normal GH cells with tumour cells in undifferentiated acidophil adenomas demonstrated significantly larger volumes of nuclei, rough endoplasmic reticulum, Golgi fields, immature secretory granules and of the cell membranes, and also of nucleoli and of the mitochondria. Secretory granules and lysosomes were observed more frequently than in normal GH cells. In a comparison of both adenoma types, the well differentiated acidophil adenomas contained significantly larger volumes of the unorganized cytoplasm, secretory granules and of cell membranes, whereas more points were counted on the rough endoplasmic reticulum and on the mitochondria in undifferentiated acidophil adenomas. The differences between the normal GH cells and the GH cell in undifferentiated adenomas (mainly larger nucleoli, larger volumes of the rough endoplasmic reticulum and the lower volumes of secretory granules) indicate a higher secretory activity in the adenomas. The significant differences between the well differentiated and the undifferentiated adenomas (mainly the increased volumes of mitochondria and of the unorganized cytoplasm in the undifferentiated tumours) indicate a lower grade of differentiation and may be interpreted as signs of increased proliferation.This publication contains results from the thesis submitted by Karin Rübenach-Gerz (Hamburg 1986)Dedicated to Prof. Dr. Klaus-Joachim Hempel on the occasion of his 60th birthday     

Ultrastructural studies on postnatal differentiation of neurons in the substantia gelatinosa of rat cervical spinal cord

Neuroblasts of the substantia gelatinosa at birth were small with large oval nuclei and scanty cytoplasm. The cytoplasm possessed ribosomes and mitochondria. Granular endoplasmic reticulum and Golgi complexes were generally absent or rudimentary. Electron dense bodies were seldom observed. By the end of the first week, the nuclei of several cells demonstrated early nuclear invaginations; cytoplasm exhibited growth cones, a well developed granular endoplasmic reticulum and Golgi complexes. At several points the channels of endoplasmic reticulum became continuous with the perinuclear space. By the end of the second week, differentiation of the neuroblasts was more advanced. More nuclei showed invagination of their contour. The cytoplasm revealed well developed granular endoplasmic reticulum and multiple Golgi complexes. Numerous vesicles and dense bodies were found adjacent to the Golgi complexes. Arrays of agranular endoplasmic reticulum also appeared late in the second week. By the third week, features of neuronal differentiation, such as nuclear invaginations, granular endoplasmic reticulum, agranular membrane configurations, multiple Golgi complexes and dense bodies in the cytoplasm became well established.     

Physiology: Morphological characteristics of human endometrial epithelial cells cultured on rat-tail collagen matrix

Epithelial cells were isolated from normal human endometriumand cultured on reconstituted matrices of rat-tail collagengels. Cells attached within 24 h after plating. Initially, epithelialcells were not structurally polarized, had projections fromboth apical and basal domains and were generally flat to cuboidalin shape. When the gels were made free floating 36–48h after initiation of the cultures, the epithelial cells becamecolumnar in shape as the gels underwent contraction. Althougha maintained growth profile was observed during the 10 daysof culture, there was a linear decrease in gel matrix diameteralong with increasing loss of transparency. Electron microscopyrevealed the presence of apical microvilli, junctional complexes,lipid droplets and endoplasmic reticulum in cultured epithelialcells. The basolateral dilatations and lateral membrane plicationswere seen in these cells by 6–8 days in culture. Withgel contraction, rearrangement of matrix material was observed.Occasionally there were basal lamina-like structures adjacentto the flattened basal surface and the formation of gland-likestructures within the matrix. The three-dimensional primaryculture of human epithelial cells on collagenous biomatrix appearsto be a potential experimental tool for the study of cell-celland cell-matrix interactions, and of the study of the effectsof endocrine and paracrine factors on these cells in vitro.     

Ultrastructural studies on postnatal differentiation of neurons in the substantia gelatinosa of rat cervical spinal cord.

Neuroblasts of the substantia gelatinosa at birth were small with large oval nuclei and scanty cytoplasm. The cytoplasm possessed ribosomes and mitochondria. Granular endoplasmic reticulum and Golgi complexes were generally absent or rudimentary. Electron dense bodies were seldom observed. By the end of the first week, the nuclei of several cells demonstrated early nuclear invaginations; cytoplasm exhibited growth cones, a well developed granular endoplasmic reticulum and Golgi complexes. At several points the channels of endoplasmic reticulum became continuous with the perinuclear space. By the end of the second week, differentiation of the neuroblasts was more advanced. More nuclei showed invagination of their contour. The cytoplasm revealed well dev-loped granular endoplasmic reticulum and multiple Golgi complexes. Numerous vesicles and dense bodies were found adjacent to the Golgi complexes. Arrays of agranular endoplasmic reticulum also appeared late in the second week. By the third week, features of neuronal differentiation, such as nuclear invagination, granular endoplasmic reticulum agranular membrane configurations, multiple Golgi complexes and dense bodies in the cytoplasm became well established.     

Electron microscopy of umbilical cord endothelial cells in preeclampsia

We have studied by means of transmission electron microscopy the umbilical cord endothelial cells in 11 preeclamptic women. Endothelial cells exhibited oval, round, elongated, flattened, triangular or polygonal shapes. The nuclei displayed shallow and deep invaginations of nuclear envelope. The endoplasmic reticulum appeared highly dilated and vacuolated. The swollen mitochondria showed cristae fragmentation. Areas of focal necrosis were appreciated throughout the cytoplasm. A marked enlargement of subendothelial space and the presence of an electron dense granular material were also found. The findings reveal activation and injury of endothelial cells and disruption of endothelial cell layer.     

Studies on the fine structure of ovarian steroid-secreting cells in the rabbit. I. The normal interstitial cells

In terms of their light microscopic appearance and fine structure the ovarian interstitial cells of the rabbit are typical steroid-secreting cells. They are characterized by an abundance of agranular endoplasmic reticulum, spherical mitochondria with closely packed lamellar cristae, lipid droplets which appear to arise independently of the endoplasmic reticulum, conspicuous Golgi areas, a cytoplasm containing ribosomes and variable numbers of glycogen granules. A feature of the differentiation of the cells from the theca interna of atretic follicles or the stroma is the enlargement of the multiple Golgi areas and the progressive accumulation of agranular endoplasmic reticulum, possibly by “budding” from the Golgi cisternae. “Light” and “dark” cells are observed, the latter being characterized by a more closely packed agranular endoplasmic reticulum which tends to be tubular in type, that of the “light” cell being vesicular. Electron dense material (lipid?) is found in the vesicles and tubules of the agranular endoplasmic reticulum and in the Golgi cisternae; it may indicate a role of these structures in the biosynthesis of steroidal hormone. No fine structural changes specifically associated with pregnancy were observed. Degenerative changes are common and are described. The role of the interstitial cells, especially in relation to the production of 20 alpha-hydroxyprogesterone, is discussed.     

Effects of ACTH on membranous whorls in the adrenal gland of the Mongolian gerbil

The ultrastructure of whorls of rough endoplasmic reticulum in the adrenal gland of the Mongolian gerbil (Meriones unguiculatus) was examined during and after treatment with ACTH. Whorls were loosely wound after treatment for one day and consisted of only a few paired membranes. Focal areas of increased tubular smooth endoplasmic reticulum were seen throughout the cytoplasm of the cells. Whorls disappeared altogether after three days of ACTH treatment. The structures reappeared one day after stopping the ACTH injections and seemed to enlarge progressively by addition of membranes to the periphery of the structures. Numerous vesicles and sometimes parallel cisternae of rough endoplasmic reticulum were observed in the cytoplasm of adrenocortical cells containing newly forming whorls. The whorls apparently serve as a readily available reserve of rough endoplasmic reticulum, which can transform into smooth reticulum upon stimulation with ACTH.