ELEKTRONENMIKROSKOPISCHE UNTERSUCHUNGEN AN DEN OVARIEN NEUGEBORENER MÄUSE NACH BEHANDLUNG MIT HUMANEM HYPOPHYSÄREM GONADOTROPIN (HHG)

1968 ◽  
Vol 57 (2) ◽  
pp. 279-288 ◽  
Author(s):  
R. Beltermann ◽  
H.-E. Stegner
Keyword(s):  
Electron Microscopy ◽  
Neutral Lipids ◽  
Single Injection ◽  
Light And Electron Microscopy ◽  
Interstitial Cells ◽  
Follicular Atresia ◽  
Mouse Ovary ◽  
Human Pituitary ◽  
Newborn Mice ◽  
Pituitary Glands

ABSTRACT Ovaries of newborn NMRI-mice were examined by light and electron microscopy. They were compared with ovaries of newborn mice stimulated by a single injection of 10 μg of a highly purified preparation of gonadotrophin isolated from human pituitary glands (HHG). In treated animals the development of follicles was accelerated. While in unstimulated ovaries interstitial cells could not be demonstrated before the 9th day of life, typical interstitial cells could be identified 24 h after the injection of HHG. The ultrastructure of interstitial cells of the mouse ovary can be compared with that of interstitial cells of testes and of steroid producing cells of the adrenal cortex. These cells are characterized by big round mitochondria with lamelliform and villiform cristae and a well developed endoplasmic system. They are rich in neutral lipids. Evidently there is no correlation between the development of interstitial cells of newborn mice and follicular atresia.

scholarly journals Trypanosoma congolense in the Microvasculature of the Pituitary Gland of Experimentally Infected Boran Cattle (Bos indicus)

1993 ◽  
Vol 30 (5) ◽  
pp. 401-409 ◽  
Author(s):  
G. Abebe ◽  
M. K. Shaw ◽  
R. M. Eley
Keyword(s):  
Electron Microscopy ◽  
Extracellular Matrix ◽  
Structural Changes ◽  
Bos Indicus ◽  
Light And Electron Microscopy ◽  
Trypanosoma Congolense ◽  
Glossina Morsitans ◽  
Glossina Morsitans Centralis ◽  
Pituitary Glands ◽  
Female Control

The pituitary glands of seven Boran cattle ( Bos indicus), five infected with a clone of Trypanosoma congolense IL 1180 (ILNat 3.1) transmitted by Glossina morsitans centralis and two uninfected controls, were examined by light and electron microscopy 43 (experiment 2) or 56 (experiment 1) days after fly challenge. The three cattle used in the first experiment included a 15-month-old female (No. 1), a 24–month-old female (No. 2), and a 21–month-old male (No. 3) as a control. In the second experiment, four cattle were used: two females (Nos. 4, 5) and one male (No. 6), all between 15 and 24 months of age, and one female control (No. 7) of similar age. In all the infected animals, dilation of both the sinusoids and microvasculature was apparent, as was an increase in the thickness of the extracellular matrix between the pituitary lobules. Trypanosomes were found in the microvasculature of the adenohypophysis and neurohypophysis in all the infected animals. Focal degenerative changes were seen in the adenohypophyseal section of glands from the infected animals euthanatized 56 days post-infection. These degenerative structural changes were confined to the somatotrophs cells. The possible role that trypanosomes in the microvasculature may play in inducing pituitary damage and dysfunction is discussed.

Parallel Intralysosomal Amyloid Fibrils, a Possible Result of Phagocytosis

1977 ◽  
Vol 14 (4) ◽  
pp. 407-419 ◽  
Author(s):  
E. Gruys ◽  
M. Castaño
Keyword(s):  
Electron Microscopy ◽  
Enzyme Activity ◽  
Acid Phosphatase ◽  
Enzyme Histochemistry ◽  
Amyloid Fibrils ◽  
Light And Electron Microscopy ◽  
Interstitial Cells ◽  
Mesenchymal Cells ◽  
Parallel Arrangement

Vacuoles of mesenchymal cells in the papillae of bovine kidneys with amyloidosis were studied by histochemical electron microscopy for acid phosphatase as a marker for lysosomes. The vacuoles contained parallel amyloid fibrils. The vacuoles of reticular interstitial cells were found to be lysosomes. Vacuoles of macrophage-like cells of the same papillae were positive, partially positive, or negative for the enzyme activity. A suspension of papillary material was injected subcutaneously in rats in a 21-day light and electron microscopy and enzyme histochemistry study. Amyloid was demonstrated in vacuoles of macrophages throughout this period and initially also in neutrophils. In most vacuoles amyloid fibrils were randomly arranged but in others parallel arrangement was demonstrated. Amyloid was only at the inoculation sites. Intralysosomal bovine amyloid may occur in parallel fibrillar arrangement without a definite indication for amyloid production.

The Mouse Testis as a Model for the Study of Age Related Fine Structural Changes

1975 ◽  
Vol 33 ◽  
pp. 586-587
Author(s):  
J.E. Johnson ◽  
J. Miquel
Keyword(s):  
Electron Microscopy ◽  
Sertoli Cells ◽  
Structural Changes ◽  
Light And Electron Microscopy ◽  
Interstitial Cells ◽  
Comparative Investigation ◽  
The Other ◽  
Vascular Perfusion ◽  
Dense Bodies ◽  
Age Related

In studying the morphology of aging cells, it is generally concluded that different changes occur in fixed postmitotic cells as compared to those cells which divide actively throughout life. The testis appears to be an excellent model for a comparative investigation of such changes, since it contains some cells which are essentially non-dividing in adulthood (Sertoli cells and interstitial cells) as well as other cells which divide continuously in mature animals (spermatogonia and spermatocytes).We have examined, by light and electron microscopy, the testes of numerous C57BL/6J mice at ages ranging from 3 to 30 months. All tissues were fixed by vascular perfusion with paraformaldehyde and glutaraldehyde mixtures in phosphate buffer.Sertoli cells (Fig. 1) and interstitial cells (Fig. 2) in aging animals contain a large number of dense bodies (presumably lipofuscin). On the other hand, dense bodies are not seen in spermatogonia, spermatocytes or spermatids (Fig. 1).

Microanalysis of Fish Ovarian Follicular Atresia: A Possible Synergic Action of Somatic and Immune Cells

2020 ◽  
Vol 26 (3) ◽  
pp. 599-608 ◽  
Author(s):  
Doaa M. Mokhtar ◽  
Marwa M. Hussein
Keyword(s):  
Electron Microscopy ◽  
Immune Cells ◽  
Smooth Muscle Actin ◽  
Light And Electron Microscopy ◽  
Morphological Characteristics ◽  
Follicular Atresia ◽  
Phagocytic Cells ◽  
Nonbreeding Season ◽  
Transmission Electron ◽  
Rodlet Cells

AbstractThe present study describes in detail the morphological characteristics of the process of ovarian follicular atresia in Redbelly tilapia (Coptodon zillii) during the nonbreeding season using light and electron microscopy and immunohistochemistry. The follicular regression process was initiated with shrinkage and disintegration of the nuclear membrane of oocytes resulting in dispersing of chromatin within the ooplasm, followed by marked hyperplasia and hypertrophy of follicular and granulosa cells, which exhibited a strong phagocytic activity to engulf the liquefied yolk particles. Rodlet cells and granulocytes were recorded on the follicular wall and invaded the regressed follicles. Rodlet cells expressed a strong immunoreactivity to matrix metalloperoxidase (MMP-9) and α-smooth muscle actin, while neutrophils expressed a strong reactivity to Myeloperoxidase-3 (MPO). In the advanced stage of follicular atresia, the yolk was almost phagocytized and resorbed and the regressed follicle lost its integrity and appeared to be formed of a cellular mass of phagocytic cells. Transmission electron microscopy revealed the presence of neutrophils, eosinophils, and dendritic cells within the atretic follicle in between these phagocytic cells. Moreover, numerous lysosomes, granules, and phagosomes were observed within the cytoplasm of both phagocytic cells and granulocytes. Telocytes were also demonstrated within the highly thickened richly vascularized theca layer during the late stages of follicular atresia. Immunohistochemical staining for caspase-3 established the participation of apoptosis in the advanced stages of follicular regression. Immune cells, rodlet cells, and telocytes in combination with follicular cells play an essential role in follicular atresia. In conclusion, the present study provides a new evidence on the role of both somatic and immune cells in the phenomenon of ovarian follicular atresia in Redbelly tilapia (Coptodon zillii) during the nonbreeding season.

Pituitary Follicular Cells: Their Origin, Possible Function and Fate

1974 ◽  
Vol 32 ◽  
pp. 34-35
Author(s):  
E. Horvath ◽  
K. Kovacs ◽  
G. Penz ◽  
C. Ezrin
Keyword(s):  
Fine Structure ◽  
Secretory Granules ◽  
Follicular Cells ◽  
Human Pituitary ◽  
Rat Pituitary ◽  
Pituitary Glands ◽  
Junctional Complexes

Follicular structures, in the rat pituitary, composed of cells joined by junctional complexes and possessing few organelles and few, if any, secretory granules, were first described by Farquhar in 1957. Cells of the same description have since been observed in several species including man. The importance of these cells, however, remains obscure. While studying human pituitary glands, we have observed wide variations in the fine structure of follicular cells which may lead to a better understanding of their morphogenesis and significance.

Two Distinct Types of Microfilaments in the Cytoplasm of Human Adenohypophysial Cells

1973 ◽  
Vol 31 ◽  
pp. 668-669
Author(s):  
E. Horvath ◽  
K. Kovacs ◽  
I. E. Stratmann ◽  
C. Ezrin
Keyword(s):  
Pituitary Tumors ◽  
Average Diameter ◽  
Anterior Lobe ◽  
Uranyl Acetate ◽  
Type I ◽  
Breast Cancer Patients ◽  
Human Pituitary ◽  
Severe Diabetes ◽  
Pituitary Glands ◽  
Membrane Bound

Surgically removed human pituitary glands as well as pituitary tumors fixed in glutaraldehyde, postfixed in osmium tetroxide, embedded in epon resin, stained with uranyl acetate and lead citrate have been investigated by electron microscopy in order to correlate ultrastructure with functional activity. In the course of this study two distinct types of microfilaments have been identified in the cytoplasm of adenohypophysiocytes.Type I microfilaments (Fig. 1) were found in the cytoplasm of anterior lobe cells of five female subjects with disseminated mammary cancer and two patients with severe diabetes mellitus. The breast cancer patients were treated pre-operatively for various periods of time with different doses of oxysteroids. The microfilaments had an average diameter of JO A, formed parallel bundles, were scattered irregularly in the cytoplasm and were frequently located in the perikaryon. They were not membrane-bound and failed to show any periodicity.

The Morphology of Vacuolated Cells in the Liver Following Administration of Vitamin A.

1973 ◽  
Vol 31 ◽  
pp. 408-409
Author(s):  
Odell T. Minick ◽  
Hidejiro Yokoo ◽  
Fawzia Batti
Keyword(s):  
Electron Microscopy ◽  
Body Weight ◽  
Vitamin A ◽  
Light And Electron Microscopy ◽  
Liver Cells ◽  
Prominent Feature ◽  
Vascular Space ◽  
Vacuolated Cell ◽  
Vacuolated Cells ◽  
Vacuolated Cytoplasm

Vacuolated cells in the liver of young rats were studied by light and electron microscopy following the administration of vitamin A (200 units per gram of body weight). Their characteristics were compared with similar cells found in untreated animals.In rats given vitamin A, cells with vacuolated cytoplasm were a prominent feature. These cells were found mostly in a perisinusoidal location, although some appeared to be in between liver cells (Fig. 1). Electron microscopy confirmed their location in Disse's space adjacent to the sinusoid and in recesses between liver cells. Some appeared to be bordering the lumen of the sinusoid, but careful observation usually revealed a tenuous endothelial process separating the vacuolated cell from the vascular space. In appropriate sections, fenestrations in the thin endothelial processes were noted (Fig. 2, arrow).

Altered thymic epithelial cells may be decisive for Moloney virus-induced lymphoma development

1983 ◽  
Vol 41 ◽  
pp. 784-785
Author(s):  
U.I. Heine ◽  
G.R.F. Krueger ◽  
E. Munoz ◽  
A. Karpinski
Keyword(s):  
Epithelial Cells ◽  
Leukemia Virus ◽  
Light And Electron Microscopy ◽  
Tumor Development ◽  
Current Evidence ◽  
Thymic Epithelial Cells ◽  
Thymic Tissue ◽  
Newborn Mice ◽  
Moloney Leukemia Virus ◽  
Differentiation Block

Infection of newborn mice with Moloney leukemia virus (M-MuLV) causes a T-cell differentiation block in the thymic cortex accompanied by proliferation and accumulation of prethymic lymphoblasts in the thymus and subsequent spreading of these cells to generate systemic lymphoma. Current evidence shows that thymic reticular epithelial cells (REC) provide a microenvironment necessary for the maturation of prethymic lymphoblasts to mature T-lymphocytes by secretion of various thymic factors. A change in that environment due to infection of REC by virus could be decisive for the failure of lymphoblasts to mature and thus contribute to lymphoma development.We have studied the morphology and distribution of the major thymic cell populations at different stages of tumorigenesis in Balb/c mice infected when newborn with 0.2ml M-MuLV suspension, 6.8 log FFU/ml. Thymic tissue taken at 1-2 weekly intervals up to tumor development was processed for light and electron microscopy, using glutaraldehyde-OsO4fixation and Epon-Araldite embedding.

A Resorcinol-Formaldehyde Resin as an Embedding Material for Electron Microscopy of Membranes

1969 ◽  
Vol 27 ◽  
pp. 328-329 ◽  
Author(s):  
J. G. Robertson ◽  
D. F. Parsons
Keyword(s):  
Electron Microscopy ◽  
Osmium Tetroxide ◽  
Neutral Lipids ◽  
Lipid Extraction ◽  
Water Soluble ◽  
Formaldehyde Resin ◽  
Electron Microscope Autoradiography ◽  
Resorcinol Formaldehyde ◽  
Major Disadvantage ◽  
Cell Organization

The extraction of lipids from tissues during fixation and embedding for electron microscopy is widely recognized as a source of possible artifact, especially at the membrane level of cell organization. Lipid extraction is also a major disadvantage in electron microscope autoradiography of radioactive lipids, as in studies of the uptake of radioactive fatty acids by intestinal slices. Retention of lipids by fixation with osmium tetroxide is generally limited to glycolipids, phospholipids and highly unsaturated neutral lipids. Saturated neutral lipids and sterols tend to be easily extracted by organic dehydrating reagents prior to embedding. Retention of the more saturated lipids in embedded tissue might be achieved by developing new cross-linking reagents, by the use of highly water soluble embedding materials or by working at very low temperatures.

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