bluuebunny/crossref_metadata_2025 huggingface dataset:
Ultrastructural & image analysis of mitochondrial changes in myocardium of copper-deficient rats administered a toxic dose of cocaine
Authors: Bielenberg U. , Burns W. , Smith J.C.
Published: June 2020

We examined the effects of a single dose of cocaine (Coc) on the myocardium of rats fed copper sufficient (CuS) compared to copper deficient (CuD) diets. Weanling males were fed either CuS (n=13) or CuD (n=12) for 7 weeks. Ten in each group, (paired for Cu status), were injected (ip) with Coc-HCL (80-90mg/kg bw), 5 served as controls

Rats which survived for 15 minutes were killed and heart tissue was obtained for light and transmission electron microscopy as well as Cu analysis. Tissue for ultrastruetural study was fixed in Carson’s fixative and post fixed in osmium tetroxide.

Myocardial foci showed necrosis, fibrosis, and inflammation in all rats given cocaine but were more severe in the CuD group. CuS controls (no Coc) showed no similar lesions. Ultrastructurally the
myocardium confirmed the light microscopy findings and showed apparent increase in the number of mitochondria which were of variable sizes and shapes. Giant mitochondria, clumping and foci of
molding were observed. Crystalline configurations of cristae were also seen.
Ultrastructural effects of exogenous hydrogen peroxide on the myocardium
Authors: Oguro T. , Aida K. , Onodera T. , Ashraf M.
Published: June 2020

It has been suggested that hydrogen peroxide (H2O2) is indirectly associated with postischemic-reperfusion injury of the heart. Previously, we reported that the heart was not damaged when perfused with exogenously generated superoxide anions. However, H2O2, a dismutation product of superoxide anion severely affected the heart structure and function. In this study, we evaluated the ultrastructural changes of the cel1 membranes in isolated rat hearts and cultured myocytes follow-ing treatment with exogenous H2O2.

In the isolated hearts, 300 μM of H2O2, a concentration which was based on our earlier study was perfused for 5 minutes. For the last 2 minutes, 100 mg (2200 U/mg) of horseradish peroxidase was perfused to see the permeability of the cell membranes. In the isolated cultured myocytes, 300 μM of H2O2 was added to the medium for 30 minutes. Both the hearts and the isolated myocytes were fixed with 2.5% buffered glutaraldehyde, postfixed with 1% osmium tetroxide and were processed for electron microscopy.
Pt/Ir/C, a new, powerful coating material for High-Resolution SEM
Authors: Wepf Roger , Gross Heinz
Published: June 2020

In-lens field emission SEM allows to image specimen surfaces with subnanometer resolution by collecting type I secondary electrons, with an incident electron probe size of abut 0.5 nm in diameter. To achieve such high topographic resolution on biological specimens adequate structural preservation and high resolving thin continuous coating films are necessary.

Careful freeze-drying (“maintaining hydration shells”) followed by heavy metal shadowing at -250°C under ultra high vacuum conditions (UHV) allows to extract surface features ≤2 nm with TEM. TEM-shadowing films (Pt/C, Ta/W) are stabilized with a C-backing layer. Such a C-coat would blurr fine details when investigated with the SEM.

At the right composition (C-content 25-40%, metal content 75-60%) only about 1.5 nm thick Pt/Ir/C-films remain three-dimensionally stable when transferred to atmospheric conditions after freeze-drying samples with macromolecular dimensions. Pt/Ir/C is made by evaporating a Pt/Ir cylinder (diameter 1.5 mm, 70% Ir) inserted into a graphite rod (diameter 2 mm).
Preparation of cytoskeletons for high-resolution SEM by freeze-drying and cryosputtering
Authors: Lindroth Margaretha , Fredriksson Bengt-Ame , Bell Paul B.
Published: June 2020

We have installed a magnetron sputter-coater (Ion Tech, model 310) within a freeze-dryer, thereby making it possible to metal coat biological samples directly after drying without breaking the vacuum or increasing the temperature of the specimen. We call this cryosputtering. Theoretically cryosputtering should give better preservation of supramolecular structure because the metal coat replicates the structure of the sample while molecular structure is still preserved by low temperature and before it is changed by the rehydration that results when a dried sample is taken out into a humid atmosphere. The freeze-dryer (Tis-U-Dry Histological Freeze Dryer, model TFD-130, FTS Systems Inc., Stone Ridge, NJ, USA) is connected to a turbo molecular pump (Balzer model TSH 332), backed by a rotary vane pump (Balzer model DUO 016B). This system provides a high, clean vacuum that minimizes contamination of the sample and the sputtered metal film from backstreaming oil or other substances that are present in the low vacuum of an ordinary sputter coater.
Microtubules in crow (Corvus splendens) spermiogenesis-TEM and SEM study
Authors: Bawa S.R. , Kaur R. , Pabst M.
Published: June 2020

Amongst the birds, the passerine species posses corkscrew shaped spermatozoa. Number of published reports suggest that the microtubules are implicated in the shaping of the sperm nucleus. And that their absence or faulty orientation with respect to the spermatid nucleus results in anamolous development of the sperm head. On the other hand, Fawcett and his colleagues propose that the intrinsic forces of chromatin condensation are the sole determinant for the acquisition of a corkscrew shaped nucleus in Finch-a passerine bird. However, it is unclear whether the microtubules affect acrosome shape or if the form of the acrosome is due to the alterations manifested bythe differentiative contents of theacrosome. Scanning (SEM) and Transmission electron microscopy (TEM) of ultrathin sections and freezefracture replicas of sperm forming cells of crow, Corvus splendens, provides clearer picture of the involvement of the microtubules (MT) in the transformation and shaping of the nucleus, acrosome as well as the middle-piece.
Sperm associations in rat epididymis
Authors: Fomés Miguel W. , Burgos Mario H.
Published: June 2020

During epididymal transit a head to head association of spermatozoa has been described in guinea pig, Loris and marsupials. In guinea pig they are permanent and androgen dependent. Other type of sperm association described in nonseasonal. mammals, adopt the stiape of dense masses of degenerating spermatozoa.

In the present study a new transitory head to head association in rat spemiatozoa is described which appears at the end of the epididymal transit and dense masses of associated spennatozoa in degeneration similar to those described in the literature. The sperm samples were obtained by puncture of the 3 main epididymal regions. The emerging fluid drops were immediately suspended in a balanced salt solution, placed in a slide-cover slide chanber at 36°C, and observed and recorded with a video equipment. Other drops of epididymal fluid were fixed in Mollenhauer (1976) and processed for light microscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM).
Distribution of lectin binding sties and anionic sites in the rat zona pellucida
Authors: Skutelsky E. , Maymon R. , Bar-Shira (Maymon) B. , Shalgi R.
Published: June 2020

The zona pellucida (ZP) in mammals is an extracellular coat which surroudns the oocyte during growth, fertilization and early development, consisting of a limited number of glycoproteins. Carbohydrates residues and charge properties of the ZP are believed to have a role in sperm-egg interaction. The purpose of the present study was to furtehr characterize the specific nature and distribution of the carbohydrate residues of the ZP and cumulus cells and anionic residues at the ultrastructural level.

We used lectins as probes for specific sugar residues and polycationic colloidal gold (PCG) as a marker for aninonic sites. Immature female rats were induced to superovate. Ovulated, cumulus-oocyte complexes were isolated and fixed with 2.5% Glutaraldehyde, dehydrated and embedded in Araldite or LR-Gold. For light microscopic (LM) histochemistry, 0.5 μm sections were cut, deresined by Na-methoxide and labeled with biotin-derivatized lectins as probes and avidin biotin-peroxidase complex as visualant.
Characterization of germ cell nuclei in freeze-fracture replicas using seminiferous tubules isolated by transillumination
Authors: Morales Alfonsina , Cavicchia Juan C.
Published: June 2020

The present investigation was under taken, combining the identification of specific germ cell types present in a particular stage of the seminiferous wave with freeze-fracture techniques to follow the changing pattern of their nuclear pore distribution during spermatogenesis. Male albino adult rats were used. Segments of seminiferous tubules were separated (stages VII-VIII; IX-XI; XII-XIV) by a technique described by Parvinen and Vanha-Perttula where the stages of the cycle were recognized and isolated by transillumination under a dissecting microscope. The tubular segments were immediately fixed in glutaraldehyde, immersed in glycerol, freeze-fractured in a Balzers BAF 301 apparatus at-110°C and examined under a Siemens Elmiskop I EM. The only spermatogonia located in the studied stages (type A) are ovalcells in contact with the basal lamina. Pore distribution is non-random with a relatively in conspicuous aggregation. Preleptotene spermatocytes (stages VII-VIII) are easily identified by being numerous, their location over the basal lamina and the irrelatively small size. They exhibit a striking clustering of pores, in groups of 15-30 separated by pore-free areas (fig.1). Leptotenes (fig.2, 3) (stages IX-XI) and zygotenes (fig.4) (XII-XIII) change the pattern to a more even distributional though clearly maintaining some degree of clustering.
Correlation between blood-testis barrier development and onset of the first spermatogenic wave in normal and busulfan-treated rats
Authors: Cavicchia Juan C. , Sacerdote Fabio L.
Published: June 2020

Pregnant rats (day 13) received 10mg/kg of Busulfan i.p. in order to deplete of germ cell the testes of the new born rats. The seminiferous tubules of their off spring from postnatal age 1 day up to day 35 were examined with TEM after fixation plus intercellular tracers, and with freeze-fracture techniques. During this period, the inter-Sertoli tight junctions of controls increase both in numbers and in length. Between days 10 and 13 the seminiferous cords have numerous preleptotene and leptotene spermatocytes (Fig.1) surrounded by tracer. The inter-Sertoli junctions are tortuous and predominantly perpendicular to the basal lamina. Between ages 13 and 20 days the seminiferous epithelium reaches zygotene-pachytene stages (fig.2) identified by the presence of synaptonemal complexes. The tracer is stopped at the inter-Sertoli junctions at this stage, whereas it still permeates tubules displaying preleptotene and leptotene spermatocytes.

Freeze-fracture shows that the orientation of inter-Sertoli junctions has changed to parallel, both to each other and to the basal lamina (fig.3). In the Busulfan treated rats, the tubules continue having, up to postnatal day 30, only Sertoli cells and scanty spermatogonia.
TEM and SEM evidence for the assembly of chorion (eggshell) in the med-flyCeratitis capitata
Authors: Mouzaki Despina G. , Margaritis Lukas H.
Published: June 2020

Among all insect species the eggshell ofDrosophila melanogasteris the most thoroughly studied, consisting of the vitel line membrane, the waxlayer, the inner most chorionic layer the endochorion and the exochorion.Ceratitis capitatais a fruit in festing insect and causes serious destruction to the Greek crop. Our basic biological study aims to help us understand through the structure, the function of the eggshell of the laid egg inside the fruit.

For that reason we processed for conventional transmission and scanning E.M., follicles from different developmental stages by dissecting insects into cold Ringer’s solution.

Our results revealed that chorionis assembled by a position above the vitel line membrane. The waxlayer is secreted first and then begins the formation of the first series of cavities (fig. 1). These cavities are most probably created by a flocculent material which is found inside them and isused as a scaffolding to the cavities (fig. 2). A second series of cavities is formed over the first.
Immunoelectron microscopy on lysis of the oocyte vitelline coat induced by a protein from spermatozoa in a marine mollusk, Tegula pfeifferi
Authors: Usui Noriko , Haino-Fukushima Kazu
Published: June 2020

A protein responsible for lysis of the oocyte vitelline coat (VC), that is, a VC lysin, has been isolated from spermatozoa of the mollusk, Tegula pfeifferi. Biochemical studies using purified VC lysin and isolated VCs have revealed that the action of this VC lysin is stoichiometric rather than enzymatic. The present immunoelectron microscopic study was undertaken to obtain morphological evidence for this uncommon lytic mechanism using antibodies against the lysin and the soluble product (SP) released from the VC upon lysin treatment.

Oocytes isolated from dissected ovaries were treated with the lysin (1 mg/ml) at 25°C for 10 min until their VCs were elevated high from the oocyte surface. The lysin-treated oocytes were prefixed with either 1% glutaraldehyde (GA) for cytochemical study or 2.5% GA plus tannic acid (TA) for morphological study. To localize the lysin and the SP in the VCs, prefixed oocytes were treated with ovalbumin followed by one of the antisera or preimmune serum (control).
A New Technique to Reveal DNA “En Bloc” and in Lowicryl Ultrathin Sections: The NaOH-Formaldehyde-MA-Method
Authors: Risueño M.C. , Testillano P.S. , Tandler C.J. , Sánchez-Pina M.A. , Olmedilla A. , Ollacarizqueta M.A.
Published: June 2020

This paper deals with the developing of a new simple and repetitive technique to preferentially stain DNA-containing structures at the E.M. level that can be used “en bloc” and on sections. DNA staining techniques are scarce, being the osmium ammine one the only cytochemical method known until now that specifically stains DNA but not the proteins that are complexed with it, having been used to study chromatin ultrastructure. The osmium ammine synthesis is a complex process and, although an improvement has been lately reported, the stain is not comercially available.

Glutaraldehyde-fixedAllium cepa L. root meristematic cells,Capsicum annuum L. & Scilla peruviana L. pollen grains were treated with 0.5N NaOH in 4% formaldehyde overnight, rinsed in water and 1% acetic acid, methanol dehydrated, and inmersed in methanol-acetic anhydride (5:1) at 25ºC overnight. Then, the samples were Epon embedded. To perform the technique on sections, some samples were glutaraldehyde or formaldehyde fixed, methanol dehydrated, Lowicryl embedded at -20ºC and ultrathin sections were treated in the same way as in the “en bloc” procedure.
Microwaves: Application in Electron Microscopy
Authors: S-Y Leong Anthony , Gove David W
Published: June 2020

Microwaves (MW) are electromagnetic waves which are commonly generated at a frequency of 2.45 GHz. When dipolar molecules such as water, the polar side chains of proteins and other molecules with an uneven distribution of electrical charge are exposed to such non-ionizing radiation, they oscillate through 180° at a rate of 2,450 million cycles/s. This rapid kinetic movement results in accelerated chemical reactions and produces instantaneous heat. MWs have recently been applied to a wide range of procedures for light microscopy. MWs generated by domestic ovens have been used as a primary method of tissue fixation, it has been applied to the various stages of tissue processing as well as to a wide variety of staining procedures. This use of MWs has not only resulted in drastic reductions in the time required for tissue fixation, processing and staining, but have also produced better cytologic images in cryostat sections, and more importantly, have resulted in better preservation of cellular antigens.
Correlative Confocal and Electron Microscopy in Neurobiology
Authors: Deitch J.S. , Szarowski D.H. , Smith K.L. , Swann J.W. , Turner J.N.
Published: June 2020

We have previously demonstrated the advantages of using confocal scanning laser microscopy (CSLM) in the reflection mode to image neurons labeled with the horseradish peroxidase (HRP) -- diaminobenzidine (DAB) method. Neurons which were impaled with microelectrodes could be characterized electrophysiologically, filled with horseradish peroxidase (or biocytin), reacted with DAB and then imaged in thick section. We have extended this technique to include electron microscopic observations. The optical sections generated with the CSLM helped in localizing specific labeled parts of the tissue that otherwise would require many hours of hunting in order to find.

Neurons in 500-μm thick slices of rat hippocampus were filled with HRP via a recording micropipette and fixed for 4 h in 4% paraformaldehyde and 2.5% glutaraldehyde in Ringer’s solution. Vibratome sections were reacted with DAB (1.0 mg/ml) in 0.04% nickel ammonium sulfate, and placed in 1% OsO4 and then in uranyl acetate, each for 1 hour.
Laser Scanning Confocal Microscopy and Three-Dimesnsional Reconstruction of the Mitotic Spindles of Unequally Dividing Embryonic Cells
Authors: Holy J. , Schatten G.
Published: June 2020

One of the classic limitations of light microscopy has been the fact that three dimensional biological events could only be visualized in two dimensions. Recently, this shortcoming has been overcome by combining the technologies of laser scanning confocal microscopy (LSCM) and computer processing of microscopical data by volume rendering methods. We have employed these techniques to examine morphogenetic events characterizing early development of sea urchin embryos. Specifically, the fourth cleavage division was examined because it is at this point that the first morphological signs of cell differentiation appear, manifested in the production of macromeres and micromeres by unequally dividing vegetal blastomeres.

The mitotic spindle within vegetal blastomeres undergoing unequal cleavage are highly polarized and develop specialized, flattened asters toward the micromere pole. In order to reconstruct the three-dimensional features of these spindles, both isolated spindles and intact, extracted embryos were fluorescently labeled with antibodies directed against either centrosomes or tubulin.
A combined ultrastructural and gene molecular research for the relationship between human uterine cervical carcinoma and human papillomavirus
Authors: Lee Kun , Si Jingyi , Han Ricai , Zhang Wei , Tan Bingbing , Song Guoxing , Liu Shide , Chen Lianfong , Zhao Weiming , Jia Liping , Mai Yongyan , Zeng Yi , Zhou Yinan
Published: June 2020

There are more supports for the view that human papillomavirus (HPV) infection might be an etiological factor in the development of cervical cancer when the association of persistent condylomata is considered. Biopsies from 318 cases with squamous cell carcinoma of uterine cervix, 48 with cervical and vulvar condylomata, 14 with cervical intraepithelial neoplasia (CIN), 34 with chronic cervicitis and 24 normal cervical epithelium were collected from 5 geographic regions of China with different cervical cancer mortalities. All specimens were prepared for Dot blot, Southern blot and in situ DNA-DNA hybridizations by using HPV-11, 16, 18 DNA labelled with 32P and 3H as probes to detect viral homologous sequences in samples. Among them, 32 cases with cervical cancer, 27 with condyloma and 10 normal cervical epitheliums were randomly chosen for comparative EM observation. The results showed that: 1), 192 out of 318 (60.4%) cases of cervical cancer were positive for HPV-16 DNA probe (Table I)
Histological and Ultrastructural Alterations in Regenerating Skeletal Muscle of Older Adults Following Exercise-Induced Damage
Authors: Manfredi Thomas , Yong Lee Ho , Fielding Roger A. , Laliberte Verdon Sylvie , Evans William
Published: June 2020

Morphological studies have reported fewer muscle fibers in older men suggesting fewer motor units and therefore more force absorbed per muscle fiber. Physiologic studies concur with this information, reporting decreases in lean body mass and muscular strength, and lower levels of fitness (i.e. aerobic capacity) in older subjects. Muscle specimens taken from older adults have shown a greater occurance of non specific ultrastructural alterations, including Z disk thickening, myofibrillar focal damage, and lipufuscin granules. These findings suggest that skeletal muscle of older adults may be more susceptible to environmental stress and may not regenerate as effectively following trauma. Our laboratory has investigated the ultrastructure of thigh muscle in young adults following an exercise scheme designed to stress muscle during lengthening (i.e. eccentric exercise) and result in muscle damage. The vulnerability of the ultrastructure of older adults to exercise induced muscle damage has not been investigated. The purpose of this study is to compare the frequency of occurance of non specific myofibrillar disturbances in young and older adults, and describe the fine structure of skeletal muscle of older adults prior to, immediately following, and at a time when muscle regeneration is expected to occur.
Ultrastructural Cytochemical Study of Human Gastric Cancer: Observation of AKP ase,ACP ase,G6P ase,TPP ase and CO ase
Authors: Yuming Dong , Guanglin Yang , Wei Dong Du , Ai Liam Xu
Published: June 2020

The activities and distributions of AKPase ,ACPase,G6Pase,TPPase and COase in human normal gastric mucosa and gastric cancer tissues were studied histochemically at light microscopic level. These enzymes are the marker enzymes of cell membrane lysosome endoplasmic reticulum, Golgi apparatus and mitochondrion objectively. On the basis of the research we set up a special ultrastructural cytochemical technique and first researched into gastric cancer domesticly. Ultrastructural cytochemistry is also called electron microscopic cytochemistry. This new technique possesses both the sensitivity of cytochemical reaction andi the high resolution of electron microscope. It is characterized by direct observation,exact localization and the combination morphology with function.

The distributions of AKPase,ACPase,G6Pase,TPPase and COase in 14 cases of gastric cancer and 1 case of gastric Denign lesion were studied ultrastructurally. The results showed: 1. normal gastric epithelium had no AKPase reaction. The reaction of ACPase,G6Pase,TPPase and Coase were found in the corresponding organella, which were consistent with their function.
Ultrastructural Classification of Pituary Adenomas
Authors: Arumugam S. , Bharati Arumugam Sarasa
Published: June 2020

Adenoaas of the pituitary are no longer classified based on their tinctorial affinity to dyes. With the advent of the newer methods of sophisticated technology, it is now possible to classify. These depending upon the type of hormone secreted based either on histochemical techniques or on ultrastructural characteristics. The latter provides an insight into the cytoplasmic organelle morphology which offers a delightful feast to the eye as well.

This paper presents the ultrastructural characters of the pituitary adenoma as seen in Madras. 171 adenomas (124 males and 47 females) were seen during 1972-1989, classified at the light microscope level as 159 chromophobe, 2 basophilic, 4 eosinophilic and 6 mixed adenomas.

Ultrastructural examination showed that the sparsely granular prolactin cell adenoma is the commonest adenoma to be encountered closely followed by the growth hormone cell adenoma, null cell adenoma, the mixed cell adenoma and others.
Cytological changes induced by platinum-thymine in sarcoma-180 cells: Electron microscopy study
Authors: Ofosu Gustav
Published: June 2020

Platinum-thymine has been found to be a potent antitumor agent, which is quite soluble in water, and lack nephrotoxicity as the dose-limiting factor. The drug has been shown to interact with DNA and inhibits DNA, RNA and protein synthesis in mammalian cells in vitro. This investigation was undertaken to elucidate the cytotoxic effects of piatinum-thymine on sarcoma-180 cells in vitro ultrastructurally, Sarcoma-180 tumor bearing mice were treated with intraperitoneal injection of platinum-thymine 40mg/kg. A concentration of 60μg/ml dose of platinum-thymine was used in in vitro experiments. Treatments were at varying time intervals of 3, 7 and 21 days for in vivo experiments, and 30, 60 and 120 min., 6, 12, and 24th in vitro. Controls were not treated with platinum-thymine.

Electron microscopic analyses of the treated cells in vivo and in vitro showed drastic cytotoxic effect.
Ultrastructural evaluation of chlorine inhalation injury following treatment with nebulized sodium bicarbonate
Authors: Langlinais P.C. , Okerberg C.V. , Chisholm C. , Kim S.H. , Mason A.D. , Pruitt B.A.
Published: June 2020

Inhalation of chlorine gas is a common form of poisoning associated with industrial, household and transportation accidents. The use of inhaled 5% sodium bicarbonate solution for symptomatic treatment of chlorine gas injury has been suggested. Others have suggested possible intrapulmonary exothermic reaction from this procedure. The purpose of this study was to assess morphological alterations of the respiratory tract produced by inhalation of chlorine gas and to evaluate the therapeutic efficacy of inhaled nebulized 5% sodium bicarbonate after chlorine-induced injury.

Twelve adult male random source sheep were conditioned two weeks prior to experimental use. The sheep were exposed to chlorine gas at the rate of 10 breaths/minute for 4 minutes. Immediately following chlorine exposure the sheep were placed on a respirator. Five minutes of nebulization with either 5% sodium bicarbonate or saline was done 30 minutes post-chlorine exposure. Necropsies were performed at 24 hours and tissue samples from two areas of the trachea and 8 areas of the lung were routinely processed for light and transmission electron microscopy.
Histopathological observations of recurrent experimental autoimmune encephalomyelitis (rEAE) in female Lewis rats
Authors: Aschenbrenner J. E. , Jackson F. L. , Orr E. L. , Chang I. F. , Oakford L. X.
Published: June 2020

Experimental autoimmune enchephalomyelltis (EAE) is a disease which can be induced in Lewis rats by exposure of the animal to a source of myelin in the presence of adjuvant. Similar symptoms and histopathology are observed In people with multiple sclerosis (MS) leading to the widespread use ofEAEas an animal model forMS (1). Induction ofEAEin the male Lewis rat results In a monophasic disease characterized by a single severe occurrence of symptoms followed by spontaneous recovery. Female Lewis rats when exposed to identical stimuli will develop a recurrent form of the disease (rEAE) characterized by a temporally consistent, spontaneous secondary occurrence of clinical symptoms(2), which more closely mimics humanMS.

The goal of this preliminary study was to characterize the disease process in female Lewis rats (rEAE) using both light and transmission electron microscopy (TEM). Samples of lumbrosacral spinal cord were chosen for Initial examination. This tissue was sampled at four stages of the disease process, namely: in the primary occurrence phase (Peak 1, Day 12), the first recovery phase (Day 18), the secondary occurrence (Peak 2, Day 24) and the second recovery phase (Day 31) (seeFigure 1). Lumbrosacral spinal cord tissue from non-sensitized female Lewis rats, were used as control tissue.
Ultrastructural study of the Pseudopregnant Rat Uterus treated with Antiprogestins
Authors: Singh G. , Maitra S.C. , Singh M.M.
Published: June 2020

Steroidal antiprogestins RU-38486 and ZK-98734 have been reported to prevent progesterone induced uterine endometrial proliferation in estrogen primed rabbits, block decidual response and implantation in rats and induce abortion in rats, rabbits, monkeys and humans.

The present study is aimed to generate information about the effect of these antigestagens on uterine morphology and ultrastructure in the pseudopregnant rats.

Unilateral intraluminal peanut oil instillation on day 5 post-coitum in pseudopregnant rats induced marked decidualization as characterized by 560% increase in uterine weight. Histologically, it showed narrow lumen, low cuboidal epithelium with large rounded nuclei, loose stroma, large decidual cells (Fig. 1) and glands with closed lumen (Fig. 5). The epithelial surface appeared polygonal with short, stubby and sparse microvilli (Fig. 2), ultrastructurally, luminal as well as glandular epithelium had abundant mitochondria, polyribosomes, secretory granules, active golgi, and numerous pinocytotic vesicles representing functionally active status (Figs. 7 & 11). Decidual cells had numerous mitochrondia, inflated RER and irregular surface infoldings (Fig. 9).
vitreal cells and specialized phagocytes in the chick embryo retina: A TEM and SEM study
Authors: Cuadros M.A. , Martinez-Guerrero M.J. , Rios A.
Published: June 2020

In the chick embryo retina (days 3-4 of incubation), coinciding with an increase in cell death, specialized phagocytes characterized by intense acid phosphatase activity have been described. In these preparations, all free cells in the vitreal humor (vitreal cells) were strongly labeled. Conventional TEM and SEM techniques were used to characterize them and attempt to determine their relationship with retinal phagocytes.

Two types of vitreal cells were distinguished. The first are located at some distance from the basement membrane of the neuroepithelium, and are rounded, with numerous vacuoles and thin cytoplasmic prolongations. Images of exo- and or endocytosis were frequent; the cells showed a well-developed Golgi apparatus (Fig. 1) In SEM images, the cells was covered with short cellular processes (Fig. 3). Cells lying parallel to or alongside the basement membrane are elongated. The plasma membrane is frequently in intimate contact with the basement membrane. These cells have generally a large cytoplasmic expansion (Fig. 5).
Elemental composition of mast cell granules of the rat and tree frog: X-ray Microanalysis on fresh frozen dried ultrathin sections
Authors: Takaya Kenichi
Published: June 2020

Electron probe x-ray microanalysis using fresh air-dried spreads revealed electrolyte elements in the granules of platelets, mast cells, pancreatic acinar cells and melanocytes. Mast cell granules of the rat and tree frog are quantitatively compared by an energy dispersive spectrometry (EDS) using fresh frozen dried ultrathin sections.

Adult Wistar rats (ca. 250 g) and tree frogs (Hyla arborea japonica) of both sexes were used. Fresh frozen dried smears of rat peritoneal mast cells were prepared on the collodion-membrane covered titanium grid. Fresh frozen dried ultrathin sections of the tongue of the rat and tree frog were made by the metal contact method employing the rapid freezing apparatus (RF-2) cooled with liquid nitrogen. Ultrathin cryosections (60 nmj were cut at 163 K, transferred to the frozen specimen treating apparatus (FD-2) for freeze-drying in high vacuum at 173 K for 74-96 h. The specimens were observed first by 200kV transmission electron microscopy (TEM) and then under the scanning analytical electron microscope (X-650) for scanning transmission electron microscopy (STEM) images at an acceleration voltage of 40 kV and a specimen current of 0.2 nA.
Endocytosis and intracellular transport of colloidal gold-labeled ConA in mouse peritoneal macrophage
Authors: Piao Yingjie , Zhou Yimo , HU Wen
Published: June 2020

The purpose of this study is to investigate the endocytosis and intracellular transport of colloidal gold-labeled ConA (CG-ConA) in mouse peritoneal macrophages using pre-embedding staining method.

Labeling with CG-ConA, acid phosphotase (AcPase) cytochemistry and electron microscope (EM). Mouse peritoneal macrophages were elicited by intraperitoneal injection of glycogen, after which 1ml CG-ConA (CG 1mg/ml) was injected per mouse. At different intervals after injection of CG-ConA (5,10,20 and 30 min), the peritoneal macrophages were isolated and treated for their AcPase activity according to the produce of Gomori. The CG-ConA and AcPase activity in these macrophages were examined under TEM.

Surface distribution of CG-ConA 5-1Omin after intraperitoneal injection of CG-ConA many clusters and clumps of CG-ConA particles were formed on the macrophages (Fig. 1). The cluster formation is temperature-dependent and receptor-mediated, because the same phenomenon could be observed in the elicited macrophages after incubation with CG-ConA at 37°C in vitro, but not in those at 0-4°C and those incubated with pure CG particles. At 0-4°C CG-ConA particles were randomly and diffusely distributed over the cell surface. Aggregates of CG-ConA particles were often found between cellular processes.
Immunocytochemical localization of thymus-leukemia (TL) antigen on cryosections of thymocytes
Authors: Hartfield Cheryl , Loveland Bruce , McDowall Alasdair , Fischer Lindahl Kirsten
Published: June 2020

TL antigens are class I molecules of the major histocompatibility complex (MHC). They are present on the surface of cortical thymocytes of certain mouse strains. A recent study finds that a mitochondrially-encoded peptide (MTF) is presented on the cell surface by the MHC class I HMT molecule, which is encoded by a gene closely linked to that encoding TL. These results make it relevant to re-examine earlier reports that TL antigens can be found on mitochondria. In 1978, Jeng et al. demonstrated by classical resin embedding that, in addition to the plasma membrane, isolated mitochondria from TL+cells could also be labeled with anti-TL alloantiserum and a hemocyanin conjugate. This finding was unexpected, as there was no precedent for the presence of any class I molecules on the surface of mitochondria. However, contamination of subcellular fractions with other cellular constituents is unavoidable, and a control for plasma membrane contamination was not reported by Jeng et al.
Ultrastructural investigations of MDL 19,660-induced effects on the canine platelet and megakaryocyte
Authors: Loudy D.E. , Sprinkle-Cavallo J. , Yarrington J.T. , Thompson F.Y. , Gibson J.P.
Published: June 2020

Previous short term toxicological studies of one to two weeks duration have demonstrated that MDL 19,660 (5-(4-chlorophenyl)-2,4-dihydro-2,4-dimethyl-3Hl, 2,4-triazole-3-thione), an antidepressant drug, causes a dose-related thrombocytopenia in dogs. Platelet counts started to decline after two days of dosing with 30 mg/kg/day and continued to decrease to their lowest levels by 5-7 days. The loss in platelets was primarily of the small discoid subpopulation. In vitro studies have also indicated that MDL 19,660: does not spontaneously aggregate canine platelets and has moderate antiaggregating properties by inhibiting ADP-induced aggregation. The objectives of the present investigation of MDL 19,660 were to evaluate ultrastructurally long term effects on platelet internal architecture and changes in subpopulations of platelets and megakaryocytes.

Nine male and nine female beagle dogs were divided equally into three groups and were administered orally 0, 15, or 30 mg/kg/day of MDL 19,660 for three months. Compared to a control platelet range of 353,000- 452,000/μl, a doserelated thrombocytopenia reached a maximum severity of an average of 135,000/μl for the 15 mg/kg/day dogs after two weeks and 81,000/μl for the 30 mg/kg/day dogs after one week.
Morphological evidence of enteric nervous system degeneration in diabetic rats: The protective effects of insulin treatment and pancreas transplantation
Authors: Frantzides Constantine T. , Garancis John C. , Edmiston Charles E. , Nowak Thomas V. , Roza Allen M.
Published: June 2020

Diabetic visceral neuropathy is the most common acquired autonomic neuropathy. Most of the previous studies on the effect of diabetes on the GI tract have focused mainly on extrinsic parasympathetic and sympathetic innervation. The few studies which explored the effects of diabetes on the myenteric and submucosal plexi have reported normal neural morphology even in viscera that were clearly affected by diabetic autonomic neuropathy. The present study was designed to characterize changes in the enteric nervous system in different models of diabetes in rats, and to determine whether treatment with insulin or pancreas transplantation would have any affect on the degenerative process. Specimens from the proximal, middle, and distal small bowel as well as the colon were obtained from Sprague-Dawley streptozocin-induced diabetic rats, from BB/WOR genetically induced diabetic rats, insulin treated streptozocin-induced diabetic Lewis rats, and streptozocin-induced diabetic Lewis rats transplanted with a heterotopic pancreatic isograft. All specimens were obtained one month after induction of diabetes and paired biopsies were also obtained from age matched controls (Fig. 1). Tissues were processed fore lectron microscopic and immunohisto chemical studies (for the detection of substance P and VIP).
High-voltage electron microscopy and 3-D reconstruction of solitary chemosensory cells and Di-I labeling of primary afferent nerves
Authors: Kotrschal Kurt , Kinnamon John C. , Royer Suzanne M.
Published: June 2020

Solitary chemosensory cells (SCCs) resembling taste bud cells in shape and ultrastructure have been found in fish and amphibians. A quantitative survey in teleosts has revealed that SCCs may be even more abundant than taste bud cells. Due to their scattered distribution, however, this abundant and potentially important vertebrate chemosensory system has eluded closer examination. This situation has changed with the introduction of a suitable research model: the anterior dorsal fin (ADF) of rocklings (Gadidae, Teleostei). This specialized chemosensory organ contains several million SCCs that converge onto fine caliber recurrent facial nerve fibers. The ADF model has allowed us to investigate SCC innervation, fine structure and function.

Using high voltage electron microscopy of serial sections and computer-assisted three-dimensional reconstructions, we have obtained significant quantitative data on the spatial structure of SCC assemblages in the ADF epidermis and of synaptic contacts between SCCs and innervating facial nerves. Approximately 15% of all cells present in the ADF epidermis are SCCs, making up 30% of the epidermal volume. Unlike taste buds, the ADF contains only a single sensory cell type and lacks basal cells or specialized “supporting cells.”
Application of stereological analysis of cell volume to isolated myocytes in culture with and without adrenergic innervation
Authors: Rosenthal Jane K. , Atkins Dianne L. , Marvin William J. , Krumm Penny A.
Published: June 2020

To comprehend structural changes in cardiac myocytes accompanying adrenergic innervation, it is essential that a three dimensional analysis be performed. To date, biological studies which utilize stereological methods have been limited to cells in tissue and in organs. Our laboratory has utilized current stereological techniques for measuring absolute volumes of individual myocytes in primary culture. Cell volumes are calculated for two distinct groups of cells at 96 hours in culture: isolated myocytes and myocytes innervated with adrenergic neurons (Figure 1).

Cardiac myocytes are cultured from the ventricular apices of newborn rats. Cells are plated directly onto tissue culture dishes with or without preplated explants from the paravertebral thoracolumbar sympathetic chain. On day four cultures are photographed and marked for one-to-one cell location. Following conventional fixation and embeddment in eponate-12, the cells are relocated and mounted for microtomy. The cells are completely sectioned at 120nm in their parallel orientation to the surface of the dish (Figure 2). Serial sections are collected on formvar coated slotted grids and are recorded in sequence.
The cytoplasmic surface of acetylcholine receptor enriched Xenopus myocytes
Authors: Samuelsson Steven J.
Published: June 2020

During neuromuscular synaptogenesis nicotinic acetylcholine receptors (nAChR) diffusely arranged in the postsynaptic membrane preferentially sequester into aggregates. With time these aggregates come to collocalize with the post-junctional folds where they function as neurotransmitter receptors. I am interested in the molecular mechanism which maintains this integral membrane protein in place.I present a high resolution account of the muscle membrane/cytoskeleton at the, nAChR plaques.

Cocultures of myocytes and neural tube neurons from stage 22 Xenopus laevis embryos develop a reasonable number of ventral surface junctions. nAChRs also aggregate in muscle cultures without neurons. Receptor plaques are identified by labeling with fluorescent alpha-bungarotoxin (BTX)(Fig. 1a, 2a). In order to gain access to the cytoplasmic surface the cultures are incubated in a ZnCl2 solution, which stabilizes the R-rich ventral membrane areas, then sheared with a stream of ice-cold buffer. After immediate fixation the cellular fragments are ready for ultrastructural processingor immunocytochemistry.

The quick-freeze, deep-etch, rotary-shadow technique is best suited for high-resolution en-face observation of these preparations. Improvements in the original technique were necessary to produce a satisfactory and informative replica.
Ultrastructural study on the development of rat amygdaloid body
Authors: Manolova A. , Manolov S.
Published: June 2020

Relatively few data on the development of the amygdaloid complex are available only at the light microscopic level (1-3). The existence of just general morphological criteria requires the performance of other investigations in particular ultrastructural in order to obtain new and more detailed information about the changes in the amygdaloid complex during development.

The prenatal and postnatal development of rat amygdaloid complex beginning from the 12th embrionic day (ED) till the 33rd postnatal day (PD) has been studied. During the early stages of neurogenesis (12ED), the nerve cells were observed to be closely packed, small-sized, with oval shape. A thin ring of cytoplasm surrounded their large nuclei, their nucleoli being very active with various size and form (Fig.1). Some cells possessed more abundant cytoplasm. The perikarya were extremely rich in free ribosomes. Single sacs of the rough endoplasmic reticulum and mitochondria were observed among them. The mitochondria were with light matrix and possessed few cristae. Neural processes were viewed to sprout from some nerve cells (Fig.2). Later the nuclei were still comparatively large and with various shape.
Identification of intermediate filaments in mature mammalian skeletal muscle by TEM
Authors: Yagyu Masako , Robson Richard M. , Stromer Marvin H.
Published: June 2020

It is generally assumed that desmin in mature striated muscle cells is in the form of intermediate filaments (IFs) and that its primary locus is at or near the myofibrillar Z-lines. Although IFs have been identified by transmission electron microscopy (TEM) in embryonic and adult smooth and cardiac muscle cells and in differentiating or diseased skeletal muscle cells, IFs have rarely been unambiguously visualized in adult skeletal muscle (especially mammalian) cells by TEM. This is due in part to the small amount of IF protein in normal mature skeletal muscle, and in part to the heavily-packed, myofibril-dominated, intracellular cytoskeleton of these cells. In order to help ascertain the possible mechanism(s) of attachment of IFs to myofibrils, our objectives in this study were to identify, by TEM, IFs in adult mammalian skeletal muscle and to study the structural relationship of IFs and the muscle Z-lines.

Samples of porcine semitendinosus muscle were removed from mature animals immediately after death, isometrically restrained and fixed in Karnovsky's fixative for 3 hours at 25°C, and processed by conventional methods followed by embedment in Epon-Araldite resin.
Actin and α-tubulin immuno-EM labelings reveal differences in intra versus interphotoreceptor matrix
Authors: Järvilehto Matti , Harjula Riitta
Published: June 2020

The photoreceptor cells in the compound eyes of higher diptera are clustered in groups (ommatidia) of eight receptor cells. The cells from six adjacent ommatidia are organized into optical units, neuro-ommatia sharing the same visual field. In those ommatidia the optical axes of the photopigment containing structures (rhabdomeres) are parallel. The rhabdomeres of the photoreceptor cells are separated from each other by an interstitial i.e innerommatidial space (IOS). In the photoreceptor cell body, besides of the normal cell organelles, a cellular matrix is a structurally apparent component. Similar kind of reticular formation is also found in the IOS containing some unidentified filamentary substance, of which composition and functional significance for optical properties of vision is the aim of this report.

The prefixed (2% PA + 0.2% GA in 0.1-n phosphate buffer, pH 7.4, for 1h), frozen section blocks of the compound eye of the blowfly (Calliphora erythrocephala) were prepared by immuno-cryo-techniques. The ultrathin cryosections were incubated with antibodies of monoclonal α-tubulin and polyclonal smooth muscle actin. Control labelings of excess of antigen, non-immune serum and non-present antibody were perforated.
The association of epizootic hemorrhagic disease virus with the cytoskeleton
Authors: Nunamaker R.A. , Wigington J.G. , Nunamaker C.E.
Published: June 2020

The cells of eukaryotes are characterized by a filamentous network referred to as the cytoskeleton. It is believed that most animal viruses use the cytoplasmic or nuclear skeletal matrix during at least part of their replication cycle.

Transmission electron microscopic studies of thin sections of cells infected with epizootic hemorrhagic disease virus(EHDV), a double-stranded RNA virus belonging to the Reoviridae family, have demonstrated the presence of virus-like particles, virus-specific fibrils and tubules, and viral inclusion bodies. Studies of bluetongue virus (a closely related orbivirus) by Eaton et al. and Hyatt et al. confirmed that these virus-specific structures bind to the cytoskeleton of infected cells, and facilitated study of their viral protein content using monoclonal antibodies in immunogold labeling procedures, This study describes cytoskeletal involvement in the replication of EHDV.

The grid-cell-culture technique, preparation of cytoskeletons, and immunolabeling procedure were those described by Hyatt et al. Grids were dehydrated in a graded alcohol series, critical point dried in amyl acetate and CO2, coated with carbon and examined with a Philips LS 410 transmission electron microscope operating at 60 kv.
Ultrastructural characteristics on capillary of giant panda
Authors: Xiang-Yuan Zeng , Hang Chong , Wei Lian , Ke-juing Zhang
Published: June 2020

Electron microscopic observation on ultrastructural characteristics of the capillary ofgiant panda was presented. The samples were taken from mesentery and another samples were taken from mucosa of intestine. They were fixed in 2.5% phosphatebuffered glutaraldehyde and 1% osmic acid, and dehydrated by graded series of acetone. Then they were embedded with Epon 812. For orientation under phasecontrast microscope, 0.5--1.0 u thick sections were prepared from the epoxyembedded material. After that, ultrathin sections (30-50) were taken with ultramicrotome LKB-V type and stained by uranyl acetate and lead citrate and examined under DXB2-12 Electron Microscope.

Electron microscopic observation showed the capillary diameter in the mesentery microcirculation is larger and capillary wall is thin. The nucleus in endothelium was large and wasn't regular in the shape. Chromatin was loose in the nucleus. There was little plasma inthe endothelium and it looked loose. Organelles in the cytoplasm were little and vacuoles were more in endothelium. The distribution of plasma in the endothelium was different with endothelium of human body.