Nucleolus-like bodies (Nuages) and annulate lamellae in spermatogonia of fish-tilapia, Oreochromis niloticus

1990 ◽  
Vol 48 (3) ◽  
pp. 92-93
Author(s):  
T. Guha ◽  
P.F. Prentis
Keyword(s):  
Electron Microscopy ◽  
Oreochromis Niloticus ◽  
Osmium Tetroxide ◽  
Type A ◽  
Uranyl Acetate ◽  
Annulate Lamellae ◽  
Thin Sections ◽  
Cacodylate Buffer ◽  
Guppy Fish ◽  
Type A Spermatogonia

Type A spermatogonia in tilapia (Oreochromis ni1oticus) have been studied by electron microscopy. These are stem cells from which spermatogenesis beings in this species. In this paper we report presence of two cytoplasmic organelles, annulate lamellae and nucleolus-like bodies (nuages), in type A spermatogonia in O. niloticus.Testes were fixed in 2% gluteraldehyde for 4 hrs. at 4°C and then in 1% osmium tetroxide for 1 hr. at 4°C, both in 0.1M cacodylate buffer (pH 7.4). Fixed tissues were processed in the conventional way for electron microscopy. Thin sections of tissues were stained by uranyl acetate and lead citrate. These were examined in a Carl Zeiss electron microscope operated at 40kV.Nucleolus-like bodies (nuages) have been reported in rat spermatocytes, early postimplantation rat embryos, fish and amphibian oocytes and guppy (fish) spermatogonia. Annulate lamellae have been found in fish spermatogonia and oocytes. Type A spermatogonia (Figs. 1,2,3,4) in O. niloticus show presence of nucleolus-like bodies (nuages) and annulate lamellae in the cytoplasm.

Membranous alterations in the cytoplasm and nucleus in a primitive neuroectodermal tumor of the brain

1978 ◽  
Vol 36 (2) ◽  
pp. 628-629
Author(s):  
C. N. Sun ◽  
C. Araoz ◽  
H. J. White
Keyword(s):  
Nuclear Envelope ◽  
Tumor Cells ◽  
Osmium Tetroxide ◽  
Primitive Neuroectodermal Tumor ◽  
Uranyl Acetate ◽  
Neuroectodermal Tumor ◽  
Annulate Lamellae ◽  
Lead Citrate ◽  
Thin Sections ◽  
The Brain

The ultrastructure of a cerebral primitive neuroectodermal tumor has been reported previously. In the present case, we will present some unusual previously unreported membranous structures and alterations in the cytoplasm and nucleus of the tumor cells.Specimens were cut into small pieces about 1 mm3 and immediately fixed in 4% glutaraldehyde in phosphate buffer for two hours, then post-fixed in 1% buffered osmium tetroxide for one hour. After dehydration, tissues were embedded in Epon 812. Thin sections were stained with uranyl acetate and lead citrate.In the cytoplasm of the tumor cells, we found paired cisternae (Fig. 1) and annulate lamellae (Fig. 2) noting that the annulate lamellae were sometimes associated with the outer nuclear envelope (Fig. 3). These membranous structures have been reported in other tumor cells. In our case, mitochondrial to nuclear envelope fusions were often noted (Fig. 4). Although this phenomenon was reported in an oncocytoma, their frequency in the present study is quite striking.

Electron Microscopy as an aid to diagnosis in pediatric hematology/oncology

1989 ◽  
Vol 47 ◽  
pp. 1062-1063
Author(s):  
K. L. Saving ◽  
R. C. Caughey
Keyword(s):  
Electron Microscopy ◽  
Phosphate Buffer ◽  
Osmium Tetroxide ◽  
Uranyl Acetate ◽  
En Bloc ◽  
Thin Sections ◽  
Megakaryoblastic Leukemia ◽  
Pediatric Hematology ◽  
Transmission Electron ◽  
Microscopy Techniques

This presentation is designed to demonstrate how scanning and transmission electron microscopy techniques can be utilized to confirm or support a variety of unusual pediatric hematologic/oncologic disorders. Patients with the following diagnoses will be presented: (1) hereditary pyropoikilocytosis, (2) familial erythrophagocytic lymphohistiocytosis, (3) acute megakaryoblastic leukemia, and (4) pseudo-von Willebrand’s disease.All transmission and scanning electron microscopy samples were fixed in 2.5% glutaraldehyde, rinsed in Millonig’s phosphate buffer, and post-fixed with 1% osmium tetroxide. The transmission samples were then en bloc stained with 0.5% uranyl acetate, rinsed with Walpole ’ s non-phosphate buffer, dehydrated with graded series of ethanols and embedded with Epon 812 epoxy resin. Ultramicrotomy thin sections were stained with uranyl acetate and lead citrate and scanned using a JEOL-JEM 100C, The scanning samples were dehydrated with graded series of ethanols, critical point dried with CO2, gold-coated, and scanned using a JEOL-JSM 35. The peroxidase samples were fixed in 3% glutaraldehyde, incubated in diaminobenzidine (DAB), dehydrated with ethanol, embedded with Epon 812, and scanned without post-staining using a JEOL-JEM 100C.

Ultrastructural Characteristics of Vaginal Epithelium of Persistent Estrous Rats

1985 ◽  
Vol 43 ◽  
pp. 658-659
Author(s):  
Khosho Francis K. ◽  
Kaufmann Robert C. ◽  
Amankwah Kofi S.
Keyword(s):  
Osmium Tetroxide ◽  
Uranyl Acetate ◽  
Ruthenium Red ◽  
Female Rats ◽  
Constant Light ◽  
Ultrastructural Changes ◽  
Vaginal Smears ◽  
Thin Sections ◽  
Cacodylate Buffer ◽  
Ultrastructural Characteristics

Adult female rats exposed to constant light will develop anovulatory acyclicity characterized by persistent vaginal cornification (PE) and formation of multiple large cystic follicles on the ovaries. The purpose of the present communication is to describe the ultrastructural changes in vaginal epithelia in PE rats as compared to that in normal estrous rats.Persistent vaginal estrous with PCO was induced in a group of Sprague-Dawely rats by exposure to constant light for 50-150 days. Rats in normal estrous, as determined by vaginal smears, were used as controls. Nembutal- anethesized rats were perfused through the aorta with 2.5% gluteraldehyde in 1M sodium cacodylate buffer (pH 7.3). The mucosa of the vaginal folds just inferior to the cervix were dissected by microsurgery, postfixed, stained with 0.5% ruthenium red in 1% osmium tetroxide, dehydrated, and embedded in polybed. Thick sections (1μ) were stained with toludine blue for light microscopy studies. Thin sections were stained with uranyl acetate and lead citrate.

Banded Structure in a Hepatocellular Carcinoma

1977 ◽  
Vol 35 ◽  
pp. 510-511
Author(s):  
E. C. Chew ◽  
W. C. Chan
Keyword(s):  
Electron Microscopy ◽  
Hepatocellular Carcinoma ◽  
Osmium Tetroxide ◽  
Periodic Acid ◽  
Uranyl Acetate ◽  
Lead Citrate ◽  
Periodic Acid Schiff ◽  
Cacodylate Buffer ◽  
Tissue Area ◽  
Neural Tumor

Extracellular banded structures were first reported by Luse (1) in a neural tumor and subsequently by others in many types of tissues. This subject was summerized in detail by Sun and White in 1975 (2). This communication reports observations of banded structures discovered by electron microscopy in the study of a human hepatocellular carcinoma. The tissue was fixed in 3% glutaraldehyde in 0.1 M cacodylate buffer and post-fixed in buffered osmium tetroxide. Sections were stained with uranyl acetate and lead citrate. Thick sections, about 1 - 2 μ, were stained with periodic acid-Schiff's reagent involving heating of the slides.Banded structures are observed in the connective tissue area intermingled with collagen fibrils and are usually fusiform in shape (Fig. 1). The fusiform bodies average 0.5 μ in diameter and are outlined with periodicity of 800 to 1000 A°. Each period consists of a light and a dark band. Fine filaments of about 24 A° in thickness are present in the light bands (Fig. 2). They are also found to be periodic acid-Schiff positive (Fig. 3).

Unusual Inclusions in Neutrophils of two Human Renal Allografts

1976 ◽  
Vol 34 ◽  
pp. 242-243
Author(s):  
R. Valenzuela ◽  
S.D. Deodhar ◽  
D.G. Osborne ◽  
W.E. Braun ◽  
L.H.W. Banowsky
Keyword(s):  
Electron Microscopy ◽  
Osmium Tetroxide ◽  
Renal Allograft ◽  
Light And Electron Microscopy ◽  
Microscopy Study ◽  
Uranyl Acetate ◽  
Electron Microscopy Study ◽  
Thin Sections ◽  
Blood Disorder ◽  
Cadaver Donor

During a retrospective light and electron microscopy study of 158 human renal allograft biopsies, we observed, in two cases, unusual inclusions in the neutrophils trapped in glomeruli and paratubular capillaries. For electron microscopy, the specimens were fixed in glutaraldehyde, post-fixed in osmium tetroxide and embedded in Epon. Thin sections were stained with uranyl acetate and lead citrate. Eighty-six of the electron microscopically examined biopsies did not contain any neutrophils for evaluation, and only 10 biopsies showed four or more neutrophils.The two patients, A age 35 and B age 42, had received a cadaver donor renal allograft because of chronic renal failure secondary to hereditary nephritis and nephrosclerosis respectively. Neither patient was affected by any known primary blood disorder.

The Nature of Rapidly Extracted Phycocyanin from the Blue-Green Alga Plectonema Boryanum

1971 ◽  
Vol 29 ◽  
pp. 366-367
Author(s):  
M. Kessel ◽  
R. MacColl
Keyword(s):  
Self Assembly ◽  
Analytical Ultracentrifugation ◽  
Uranyl Acetate ◽  
The Self ◽  
Major Protein ◽  
Subunit Structure ◽  
Blue Green Alga ◽  
Thin Sections ◽  
Blue Green Algae ◽  
Cacodylate Buffer

The major protein of the blue-green algae is the biliprotein, C-phycocyanin (Amax = 620 nm), which is presumed to exist in the cell in the form of distinct aggregates called phycobilisomes. The self-assembly of C-phycocyanin from monomer to hexamer has been extensively studied, but the proposed next step in the assembly of a phycobilisome, the formation of 19s subunits, is completely unknown. We have used electron microscopy and analytical ultracentrifugation in combination with a method for rapid and gentle extraction of phycocyanin to study its subunit structure and assembly.To establish the existence of phycobilisomes, cells of P. boryanum in the log phase of growth, growing at a light intensity of 200 foot candles, were fixed in 2% glutaraldehyde in 0.1M cacodylate buffer, pH 7.0, for 3 hours at 4°C. The cells were post-fixed in 1% OsO4 in the same buffer overnight. Material was stained for 1 hour in uranyl acetate (1%), dehydrated and embedded in araldite and examined in thin sections.

Membrane-bound vesicles associated with the microvilli in the midgut of the freshwater microcrustacean, Daphnia magna

1983 ◽  
Vol 41 ◽  
pp. 480-481
Author(s):  
Patricia L. Jansma
Keyword(s):  
Daphnia Magna ◽  
Intestinal Epithelial Cells ◽  
Uranyl Acetate ◽  
Intestinal Epithelial ◽  
Chlamydomonas Reinhardii ◽  
Thin Sections ◽  
Saturated Water ◽  
Cacodylate Buffer ◽  
Membrane Bound ◽  
Ethanol Series

The presence of the membrane bound vesicles or blebs on the intestinal epithelial cells has been demonstrated in a variety of vertebrates such as chicks, piglets, hamsters, and humans. The only invertebrates shown to have these microvillar blebs are two species of f1ies. While investigating the digestive processes of the freshwater microcrustacean, Daphnia magna, the presence of these microvillar blebs was noticed.Daphnia magna fed in a suspension of axenically grown green alga, Chlamydomonas reinhardii for one hour were narcotized with CO2 saturated water. The intestinal tracts were excised in 2% glutaraldehyde in 0.2 M cacodyl ate buffer and then placed in fresh 2% glutaraldehyde for one hour. After rinsing in 0.1 M cacodylate buffer, the sample was postfixed in 2% OsO4, dehydrated with a graded ethanol series, infiltrated and embedded with Epon-Araldite. Thin sections were stained with uranyl acetate and Reynolds lead citrate before viewing with the Philips EM 200.

Ultrastructure of myoepithelial cell in parotid gland

1988 ◽  
Vol 46 ◽  
pp. 342-343
Author(s):  
C. N. Sun
Keyword(s):  
Parotid Gland ◽  
Osmium Tetroxide ◽  
Individual Cell ◽  
Branching Processes ◽  
Muscle Cells ◽  
Myoepithelial Cells ◽  
Uranyl Acetate ◽  
Thin Sections ◽  
Gland Carcinoma ◽  
Parotid Gland Carcinoma

Myoepithelial cells have been observed in the prostate, harderian, apocrine, exocrine sweat and mammary glands. Such cells and their numerous branching processes form basket-like structures around the glandular acini. Their shapes are quite different from structures seen either in spindleshaped smooth muscle cells or skeletal muscle cells. These myoepithelial cells lie on the epithelial side of the basement membrane in the glands. This presentation describes the ultrastructure of such myoepithelial cells which have been found also in the parotid gland carcinoma from a 45-year old patient.Specimens were cut into small pieces about 1 mm3 and immediately fixed in 4 percent glutaraldehyde in phosphate buffer for two hours, then post-fixed in 1 percent buffered osmium tetroxide for 1 hour. After dehydration, tissues were embedded in Epon 812. Thin sections were stained with uranyl acetate and lead citrate. Ultrastructurally, the pattern of each individual cell showed wide variations.

Ultrastructure of Testicular Spermatozoon of the Fish Oreochromis Niloticus

1988 ◽  
Vol 46 ◽  
pp. 278-279
Author(s):  
T. Guha ◽  
A. Q. Siddiqui ◽  
P. F. Prentis
Keyword(s):  
Electron Microscope ◽  
Oreochromis Niloticus ◽  
Osmium Tetroxide ◽  
Sperm Cells ◽  
Adult Fish ◽  
Testicular Sperm ◽  
Thin Sections ◽  
Important Fish ◽  
Testicular Spermatozoon ◽  
Diamond Knife

Tilapia, Oreochromis niloticus, is an economically important fish in Saudi Arabia. Elucidation of reproductive biology of this species is necessary for successful breeding program. In this paper we describe fine structure of testicular sperm cells in O, niloticus.Testes from young adult fish were fixed in gluteraldehyde (2%) and osmium tetroxide (1%), both in cacodyl ate buffer. Specimens were processed in the conventional way for electron microscopy and thin sections of tissues (obtained by cutting the blocks with a diamond knife) were stained by ura- nyl acetate and lead citrate. These were examined in a Carl Zeiss electron microscope operated at 40 kV to 60 kV. Sperm cells were obtained from testes by squeezing them in cacodyl ate buffer. They were fixed in gluteraldehyde (2%) in the same buffer, air dried, gold coated and then examined in a Philips scanning electron microscope (SEM) operated at 25kV.The spermatozoon of O. niloticus is consisting of head, midpiece and tail (Fig. 1).

Observations of thick and thin sections in a field-emission SEM

1994 ◽  
Vol 52 ◽  
pp. 1018-1019
Author(s):  
W. P. Wergin ◽  
S. Roy ◽  
E. F. Erbe ◽  
C. A. Murphy ◽  
C. D. Pooley
Keyword(s):  
Electron Microscope ◽  
Field Emission ◽  
Room Temperature ◽  
Osmium Tetroxide ◽  
Uranyl Acetate ◽  
Chemical Fixation ◽  
Thin Sections ◽  
Transmission Electron ◽  
Conventional Transmission Electron Microscope ◽  
Scanning Electron

Larvae of the nematode, Steinernema carpocapsae Weiser strain All, were cryofixed and freezesubstituted for 3 days in acetone containing 2% osmium tetroxide according to established procedures. Following chemical fixation, the nematodes were brought to room temperature, embedded in Spurr's medium and sectioned for observation with a Hitachi S-4100 field emission scanning electron microscope that was equipped with an Oxford CT 1500 Cryotrans System. Thin sections, about 80 nm thick, similar to those generally used in conventional transmission electron microscope (TEM) studies were mounted on copper grids and stained with uranyl acetate for 30 min and lead citrate for 5 min. Sections about 2 μm thick were also mounted and stained in a similar fashion. The grids were mounted on an Oxford grid holder, inserted into the microscope and onto a cryostage that was operated at ambient temperature. Thick and thin sections of the larvae were evaluated and photographed in the SEM at different accelerating voltages. Figs. 4 and 5 have undergone contrast conversion so that the images would resemble transmitted electron micrographs obtained with a TEM.

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