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Ultrastructure of the interstitial cells of Leydig, stimulated and unstimulated.

The interstitial cells of Leydig which lie in small groups or individually between the seminiferous tubules of the testes, or at the hilum in the ovary, are known to be active in production of androgenic substances, as well as being sensitive to the influence of various trophic hormones. Among the hormones known to be produced by these cells are testosterone, dihydrotestosterone, and estradiol. Responsiveness of the function of the Leydig cells has been demonstrated with luteinizing hormone (LH), growth hormone, follicle stimulating hormone (FSH), and probably estrogen as well as prolactin. Human chorionic gonadotrophin also may have a marked effect. Attempts to correlate the cytologic appearance of Leydig cells with various states of stimulation have revealed a number of ultrastructural appearances. Since a spectrum of cellular morphology is apparent, both in the normal and in altered physiologic states, it is hazardous to ascribe a particular ultrastructural variation to the influence of a given hormonal stimulus. Nevertheless, in normal males, three types of cells can frequently be seen: fusiform cells with ovoid nuclei, small aggregates of smooth endoplasmic reticulum (SER), and variable amounts of cytoplasmic filaments, probably representing resting cells, since they are most abundant in pre-pubertal males; light cells, the most frequent type, with well developed SER, scant rough endoplasmic reticulum (RER), and mitochondria which vary in size and shape, contain abundant lipid and frequent lipochrome deposits; and dark interstitial cells which are variable in number, derive their density from stacks of tubular SER, and may represent merely an altered response to fixation or an involutional form. In addition to immature cells and normal mature cells, two additional cell types are described in various primary testicular disorders: abnormally differentiated Leydig cells with features such as grouped mitochondria, whorls of endoplasmic reticulum, absent or fragmented Reinke's crystals and paracrystalline arrays and deficiency of lipid droplets as well as masses of microfilaments; and a multivacuolated cell type characterized by swelling of cytoplasmic organelles and absence of Reinke's crystals or paracrystalline arrays. It is also clear that the interstitial cells respond in systemic diseases, are injured by alcohol ingestion, and show involutional changes in aging. While these ultrastructural changes are now well documented, there is still a need to correlate them exactly with the various stimuli which may affect testicular function.

Aging↗
PubMed1989

Ultrastructural morphometry distinguishes Burkitt's-like lymphomas from neuroendocrine neoplasms: useful criteria applied to the evaluation of a poorly differentiated neuroendocrine neoplasm of the nasal cavity masquerading as Burkitt's-like lymphoma.

The present study describes the potential usefulness of ultrastructural morphometry in diagnosis. Ultrastructural morphometric criteria were applied to the evaluation of a poorly differentiated neuroendocrine neoplasm of the nasal cavity that was initially thought to be a Burkitt's-like lymphoma (BLL). Although the nasal lesion in question failed to stain with over 50 cell lineage-relevant antibodies, it did stain for vimentin (an intermediate filament protein) and Ki-67 (a nuclear antigen associated with cell proliferation). Routine electron microscopy revealed a primitive neoplasm with abundant cytoplasmic lipid droplets and sparse dense granules with no intercellular junctions. Treatment options, which included extensive facial surgery, prompted more study. Tissue processed for the uranaffin reaction revealed sparse uranaffin-positive granules indicating the presence of true neurosecretory granules. An ultrastructural morphometric analysis of the neoplastic nuclei of this patient placed the tumor outside the morphometric domains for BLLs (18 cases) and neuroblastomas (11 cases) and within the morphometric domain of neuroendocrine carcinomas (9 cases). A greater mean standard deviation (P less than 0.05) and mean coefficient of variation (P less than 0.02) of nuclear perimeter in the neuroendocrine (NE) group related to the BLL group indicated greater nuclear pleomorphism within the NE group as illustrated in bivariate graphic displays. The possible origin of the neoplasm within the nasal mucosa is discussed.

Burkitt Lymphoma↗
PubMed1985

Signet-ring cell lymphoma of T-cell origin. An immunocytochemical and ultrastructural study relating giant vacuole formation to cytoplasmic sequestration of surface membrane.

In contrast to previous accounts of signet-ring lymphoma as a B-cell neoplasm, we report a case of signet-ring, large-cell lymphoma of T-cell lineage. Immunologic and ultrastructural studies were performed on a subcutaneous mass noted initially, as well as on an enlarged lymph node that developed later, in a 69-year-old man. Immunologic assessment indicated strong expression of T-helper antigen (Leu 3a + b), universal T-antigens (Leu 1, 5), and Ia. There was an absence of T-suppressor/cytotoxic antigen (Leu 2a), universal T-antigens (Leu 4, 9), and immunoglobulin light and heavy chains. Collectively, these findings indicate a mature T-cell lymphoma of T-helper type in an activated (Ia+) state. In contrast to previous reports of T-cell and Ia occurring solely as surface antigens, we demonstrated pools of cytoplasmic Leu 1, 3, 5 and Ia that displaced the nucleus. The ultrastructure of the giant cytoplasmic vacuoles was identical to the microvesicle-containing vacuoles reported in signet-ring cell lymphomas of B-cell lineage. In our case of T-cell lineage, we found substantial evidence of endocytosis by the neoplastic cells and numerous giant multivesicular bodies. The pools of cytoplasmic T and Ia antigens may result from abnormal internalization of surface T-antigens or the sequestration of T-antigen-containing Golgi-derived vesicles. Our combined immunologic and ultrastructural findings suggest that aberrant membrane recycling may be the common denominator of signet-ring formation in both B- and T-cell signet-ring lymphomas.

Adenocarcinoma, Mucinous↗
PubMed1986

Humoral hypercalcemia of malignancy in nude mouse model of a canine adenocarcinoma derived from apocrine glands of the anal sac. Biochemical, histomorphometric, and ultrastructural studies.

A serially transplantable tumor line, designated CAC-8, has been developed in nude mice from a spontaneously occurring adenocarcinoma of the anal sac from a hypercalcemic dog. Nude mice with transplanted CAC-8 developed hypercalcemia (mean 16.3 +/- 0.6 mg/dl) and moderate hypophosphatemia without bone metastasis. Urinary excretion of calcium and hydroxyproline were increased 6- and 2.3-fold, respectively. Urinary excretion of cAMP was moderately increased but phosphorus excretion was not significantly altered. Serum 1,25-dihydroxycholecalciferol was increased significantly in tumor-bearing nude mice in proportion to the magnitude of tumor-induced hypercalcemia. Histomorphometric evaluation of lumbar vertebrae from nude mice with CAC-8 revealed decreased total and cortical bone volume, a 3.3-fold increase in bone resorption rate and a 2.5-fold increase in bone formation rate at the tissue level. The transplanted CAC-8 has maintained the histologic pattern of the original carcinoma up to the present sixth passage. Ultrastructural evaluation of transplanted tumor cells revealed 150-250-nm secretory-like granules. The granules did not stain by using an ultrastructural cytochemical (uranaffin) stain specific for neuroendocrine secretory granules. Ultrastructurally, the parathyroid glands of nude mice with CAC-8 appeared inactive with large intracytoplasmic whorl of agranular membranes. These data suggest the transplanted carcinoma secreted a humoral factor which resulted in hypercalcemia. The tumor line (CAC-8) propagated in nude mice represents an animal model of humoral hypercalcemia of malignancy that shares many features with the syndrome described in human patients. Unique features of this transplanted carcinoma associated with hypercalcemia include increased serum dihydroxycholecalciferol, increased rate of bone formation as well as bone resorption, an absence of bone metastases, and evidence of parathyroid gland suppression.

Adenocarcinoma↗
PubMed1986

[Ultrastructural studies of metastases of anaplastic tumors and non-Hodgkin's lymphoma as a contribution to differential diagnosis].

Difficulties in morphologic classification frequently arise in distinguishing between non-Hodgkin lymphoma and lymph node metastases from anaplastic tumors, mainly germ cell tumors and small cell carcinomas. The present study explores the role of ultrastructural features as a supplement to light microscopy in 14 cases of metastatic disease and 6 non-Hodgkin lymphomas. It appeared that the ultrastructure of the nucleoli, the arrangement of the nuclear bodies and the shape of nuclear invaginations are ultrastructural cell characteristics, which may contribute to the definitive diagnosis.

Adenocarcinoma↗
PubMed1986

[Ultrastructure and electron-histochemical properties of the glandular endometrial epithelium in women].

Ultrastructural and ultracytochemical characteristics of glandular epithelium of endometrium in 10 women with two-phase cycle were studied. Secretory transformation of glandular epithelium at ultrastructural level is manifested by deposits of glycogen in cytoplasm, giant mitochondria, hypertrophic Golgi complex and nuclear channel system. In organ endometrial cultures formation of the nuclear channel system at the stage of proliferation is induced by progesterone. Localization of ribonucleoproteins and activity of nucleoside phosphatases (ATPase and 5'-nucleotidase) in the nuclei and the channel system is described. Ultrastructural and ultracytochemical data permit to exclude nucleolar origin of the nucleolar channel system.

5'-Nucleotidase↗
PubMed1987

Ultrastructural changes associated with retroviral replication in central nervous system capillary endothelial cells.

Widespread ultrastructural alterations in the vascular basal lamina were found in the central nervous system of symptomatic mice infected with three different neuropathogenic murine leukemia viruses. These changes appeared to progress in frequency and severity in parallel with the progression of spongiform lesions and clinical symptoms. Accumulations of pleomorphic, apparently degenerating, virions were frequently seen within areas that showed marked aberrations from the normal basal lamina ultrastructure. We suggest that the observed retrovirus-associated ultrastructural changes in the endothelial basal lamina may alter normal physiologic functions and thus play a primary role in the pathogenesis of retrovirus-induced spongiform disease.

Animals↗
PubMed1986

[Nuclear ultrastructure and histocytologic features of thyroid papillary carcinoma].

Nuclear ultrastructure and histo-cytologic features of 5 cases of thyroid papillary carcinoma were studied. Three main ultrastructural features were: (1) the complex folds and invaginations of the nuclear envelope with formation of nuclear lobules and tiny bridges, (2) the intranuclear pseudoinclusions and (3) the abundant euchromatins. Under the light microscope, as mentioned above in (1), the findings were observed as the indentation of nuclear envelope and deep nuclear groove, (2) was shown as the intranuclear eosinophilic globular body and (3) as the ground-glass appearance of nucleus. The intranuclear eosinophilic globular bodies could be seen on the routine and frozen sections as well as smears. The intranuclear pseudoinclusions and eosinophilic globular bodies, were found in these 5 papillary carcinomas. At the same time, the ultrastructure and histologic features of the follicular cells were observed in 13 cases of colloid adenomas and 9 nodular goiters. None of the follicular cell nuclei showed the three features described above. The intranuclear pseudoinclusion or eosinophilic globular body was not found in any of the ultrathin and histologic sections. These results indicate that in the pathologic diagnosis of thyroid papillary carcinoma, the light microscope has more practical value than the electron microscope. Still does it, especially in the cytologic diagnosis of thyroid puncture before operation.

Carcinoma, Papillary↗
PubMed1988

Morphometry of human blood leukocyte ultrastructure: its potential value in haematology.

A review of the literature on ultrastructural morphometry of human blood leukocytes has been carried out. It is concluded that: (1) Blood leukocytes are particularly suitable for morphometric study. (2) Morphometric methods have proved valuable in defining differing cytological features of cells in various lymphoid malignancies, and in demonstrating ultrastructural differences (which could not otherwise have been detected) in monocytes and eosinophils corresponding to known functional changes. (3) Appropriate and valid numerical procedures are essential for determining morphometric equations and statistical probabilities; both morphometric measurement and statistical analysis are made easier by the use of computers. (4) Ultrastructural morphometry should ultimately find an important place in clinical haematology.

Hematologic Tests↗
PubMed1988

Histochemistry and ultrastructure of gastric submucosal vasculature in portal hypertensive rats.

We studied histochemical and ultrastructural characteristics of the gastric submucosal blood vessels in portal hypertensive (PHT) rats. PHT was induced by two-stage ligation of the portal vein. Control rats were sham operated (SO). On the fifth day after surgery portal vein blood pressure was measured and rats were killed under nembutal anesthaesia. Gastric specimens were obtained for histological, histochemical and ultrastructural assessment. PHT rats showed thickening and increased cellularity of submucosal vessels including increase in number and size of endothelial cells. All these mesenchymal cells were vimentin-positive. Thickening of vascular wall in submucosal vessels was also observed ultrastructurally together with prominent elaboration of luminal surface of endothelial cells. These changes were not observed in SO rats. All changes in PHT rats reflect vasculopathic involvement of gastric wall in portal hypertension.

Animals↗
PubMed1986

[Ultrastructural detection of messenger RNA coding for growth hormone in the rat anterior pituitary by in situ hybridization].

Ultrastructural detection of the messenger RNA coding for growth hormone in rat pituitary gland could be obtained by association of in situ hybridization and cryoultramicrotomy. Messenger RNAs were localized in the anterior pituitary gland. Silver grain densities observed in autoradiograms after in situ hybridization were dependent to incubation period and to fixation. It was necessary to determine a compromise between ultrastructural aspect and silver grain densities. Messenger RNAs were detected in somatotropic cells, identified by ultrastructural characteristics, in both the nucleus (euchromatin and nuclear membrane) and cytoplasm, in vicinity to endoplasmic reticulum.

Animals↗
PubMed1987

Ultrastructural study of peripheral lymphocytes and polymorphonuclear leukocytes in children with lysosomal enzymopathies and hyperlipoproteinemia.

On the basis of electronmicroscopic examinations of the peripheral lymphocytes and polymorphonuclear leukocytes (PMNL) in mucopolysaccharidosis of types I and II in Gaucher and Nieman-Pick diseases, in metachromatic leukodystrophy and in hyperlipoproteinemia, the ultrastructural characteristics are described. Pathological findings with vacuoles formations were observed in Gaucher disease and in metachromatic leukodystrophy against the preliminary literature. The ultrastructural pathological changes are reported from the first ultrastructural PMNL examinations in hyperlipoproteinemias. Electronmicroscopic analysis of the leukocytes is considered to give information equivalent in value to that from liver biopsy studies, but is advantageous in view of its non-invasive nature.

Child↗
PubMed1988

[Ultrastructural observations of follicular oocytes inseminated in vitro in squirrel monkeys (Saimiri sciureus)].

The ultrastructure of squirrel monkey (Saimiri sciureus) follicular oocytes inseminated in vitro was studied at the Endocrine Research Center of Michigan State University in the United States. Adult female squirrel monkeys were induced to ovulate with FSH-hCG, followed by laparoscopy 16 hours after hCG to collect ovarian follicular oocytes. A total of 45 oocytes were inseminated 21 hours after recovery by adding sperm collected by electroejaculation, followed by insemination culture for 24 hours. Inseminated oocytes were examined by light microscopy and transmission electron microscopy. Only three (6.7%) of inseminated oocytes were judged to be fertilized morphologically, but no sperm remnant was found in the cytoplasm of the oocytes. Fifteen (33.3%) had reached the second metaphase stage. As a whole, the maturation rate was 40%. Ultrastructurally, acrosome reacted sperm were observed in the cumulus cell layer, confirming the occurrence of sperm capacitation in the in vitro culture system. Cortical granules were seen throughout the cytoplasm of the germinal vesicle oocyte, especially in the vicinity of the Golgi complexes, suggesting the possibility that cortical granules originate from Golgi complexes. Metaphase chromosome, first polar body and cortical granules were observed at the second metaphase oocyte. Of three oocytes judged to be fertilized, one oocyte contained six pronucleus-like structures and another oocyte contained a pronucleus supposing fusion of two pronuclei (syngamy). But the ultrastructural morphology of a normal appearing fertilized oocyte could not be obtained. The possible cause of the low fertilization rate in the present study is supposed to be the poor follicular response and the prematurity of the cytoplasm due to repeated administrations of exogenous gonadotropins.

Acrosome↗
PubMed1988

[Effect of gamma-radiation of an extremely high dose on the cerebral cortex of the rat (ultrastructural aspects)].

For 24 h after total gamma-radiation of mature Wistar male rats (180-210 g) in the dose of 150 Gy, ultrastructural rearrangements of the cerebral sensomotor cortex are presented as small destructive changes in neurons, neuroglia and vascular endothelium. Total combination of the changes in ultrastructure of the blood capillaries and perivascular astrocytes makes it possible to suppose that permeability of the microvascular bed wall is increased. At this period, together with the destructive changes there are evidently certain compensatory-restorative processes, developing in the cerebral tissue. It is possible to suppose that already during the first hours after the radiation the ultrastructural changes of neurons are resulted not only from the direct effect of radiation, but from certain influences of the radiation damage of neuroglia and microvessels.

Adrenalectomy↗
PubMed1988

The effect of verapamil cardioplegia on myocardial ultrastructure.

The calcium channel blocker, verapamil, was evaluated as an adjunct to cold cardioplegia in 16 randomized patients with unstable angina pectoris who received saphenous vein bypass grafts. Myocardial biopsies taken before cardioplegia showed various degrees of ischemic change as assessed by ultrastructural parameters (mitochondrial swelling, matrix clearance, and sarcotubular dilatation). After reperfusion, the majority of the patients had progressive changes of ischemia, with marked mitochondrial and sarcotubular swelling, depletion of glycogen, chromatin clumping, and myofibrillar disruption; amorphous mitochondrial densities were occasionally seen. The ultrastructural changes after cardioplegia were dependent primarily on the extent of preexisting ischemic damage and did not correlate with the use of verapamil. Verapamil did not protect the ischemic myocardium during cold cardioplegia as assessed ultrastructurally.

Biopsy↗
PubMed1988

Normal ultrastructure and histochemical characteristics of canine lacrimal glands.

Lacrimal glands of 12 dogs free of ocular disease were examined to determine the normal structure of these glands. The glands consisted of tubuloacinar cells that ultrastructurally and histochemically were of a single type of secretory cell in the tubules and possibly 3 types of secretory cells in the acini. The tubular epithelium contained homogenous electron-dense granules that stained as neutral glycoconjugates (periodic acid-Schiff positive and Alcian blue and high iron diamine negative). The predominant acinar cells contained granules of lesser electron density than those of the tubules, and stained as sialomucin (Alcian blue [pH 2.5] and periodic acid-Schiff-positive, and high iron diamine-negative). A second type of acinar cell was in peripheral lobules that ultrastructurally and histochemically appeared like lipid granules (positive with oil red O and osmium tetroxide). Ultrastructurally, a third type of acinar granule was finely granular, electron-lucent, and frequently coalesced. It was not readily apparent whether the latter was an artifact, a stage in the maturation of the sialomucin granules, or a third type of acinar granule. Individual acinar cells usually had a predominance of 1 granule type, but greater than 1 granule type could be found in some cells. The basal surfaces of the acinar, tubular, and ductal cells were incompletely ensheathed by myoepithelial cells. Plasma cells, lymphocytes, mast cells, endothelial cells, fat cells, and Schwann cells composed the cellular elements of the interstitium. Lymphocytes, mast cells, and nerve endings also were found in the parenchyma.

Animals↗
PubMed1988

[Ultrastructural features of the nucleus and cytoplasm of rat trophoblast cells of the connective zone of the placenta and labyrinth].

Ultrastructural organization of the rat trophoblast cells in the connective zone of placenta and labyrinth was investigated on the 12-14th days of gestation. A clear distinction was revealed in the cytoplasm ultrastructure of two cell subpopulations within the connective zone of placenta, i.e. glycogen and trophospongium cells. The former display a well defined network of long thin channels of granular endoplasmic reticulum situated mainly around the glycogen clusters. On the contrary, the latter are rich in the smooth endoplasmic reticulum but lacking glycogen accumulation. Differences in the nucleolar ultrastructure in these two cell subpopulations are not very considerable. A characteristic feature of glycogen cells is the presence of numerous round or oval small-fibrillar nucleolus-like bodies with the diameter of granules 20 nm. The trophoblast cells of the labyrinth are heavily laden with polysomes, which sometimes attach to short channels of the granular endoplasmic reticulum. Not often there occur short profiles of the agranular endoplasmic reticulum. Nucleolus-like bodies are found in all the cell types examined. This means that the nucleolus-like bodies may arise not only on the lampbrush chromosomes in the oocytes or polytene chromosomes, but also in the somatic cells which are capable of dividing mitotically.

Animals↗
PubMed1987

Inhibition of tumor cell induced platelet aggregation by prostacyclin and carbacyclin: an ultrastructural study.

Prostacyclin and its synthetic analog carbacyclin were compared as to their abilities to inhibit tumor cell-platelet interactions. Aggregation of rat platelets was induced in vitro by homologous rat Walker 256 carcinosarcoma cells. The extent of cellular interactions was examined ultrastructurally. The ultrastructural data presented here indicate that the tumor cell-platelet interactions began with individual platelets which initiated platelet chain formation in focal association with tumor cell surfaces. By mid-phase aggregation large homotypic platelet aggregates had formed with tumor cells positioned on the external surfaces of the emboli. Tumor cell-platelet interactions became progressively more extensive as tumor cells became enmeshed with growing platelet aggregates. Prostacyclin and carbacyclin inhibited tumor cell platelet interactions in a dose-dependent manner. Carbacyclin inhibition of tumor cell induced platelet aggregation was longer in duration but carbacyclin was 10-fold less effective than was prostacyclin. We report here that prostacyclin and carbacyclin inhibit both aggregation and the ultrastructural changes associated with tumor cell-platelet interactions.

Animals↗