bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ultrastructural study of langerhans cells in a murine UV-induced tumor
Authors: Bucana C.D. , Song M.J. , Dunner K. , Sanchez R. , Kripke M.L. 
Published: June 2020

Langerhans cells (LC) are dendritic cells of the macrophage-monocyte lineage that are found in the skin, other epithelial-1ined tissues and lymphoid tissues. LC are al so present in a wide variety of pathologic tissues. LC are characterized by the presence of a unique rod- or racquet-shaped pentalaminar organelle called the Langerhans cell granule. Ultrastructural and immunohistochemical analysis of several murine UV-induced tumors revealed the presence of infiltrating cells that are morphologically similar to LC in some tumors.Murine UV-induced tumors were processed for routine histology by paraffin embedding and conventional TEM. Samples were screened for morphology of tumor cells. Tumors in which LC were identified ultrastructurally were also identified by an immunoperoxidase technique for the presence of S-100 protein.Infiltrating cells that are positive for S-100 protein are found in some UV-induced tumors. These cells are not uniformly distributed in these tumors and their numbers varied significantly from region to region. They are found among tumor cells and their dendrites are observed between tumor cells. Ultrastructural analysis of these cells showed that they exhibit a more electron lucent cytoplasm than the surrounding
cells in the tissue and they contain neither desmosomes nor tonofilaments.
Ultrastructural morphology of cells transformed with temperature-sensitive mutant of Mo-MuSV
Authors: Al-Bagdadi F. , Singh B. , Arlinghaus R.B. 
Published: June 2020

It is known that one of the abnormal behavior of cancer cells is changes in morphology. There is very little information in the literature on the morphological aspects of cell lines at the electron microscopic level transformed by viral mos gene (Culp, 1971; Hynes et al., 1978; Brown et al., 1981; Arlinghaus, 1985; Terasaki et al., 1986). NRK-6m2 is a cell line infected with a temperature sensitive mutant (tsll0) of Moloney murine sarcoma virus (Arlinghaus, 1985). The attempt in this study is to examine the ultrastructure of NRK-6m2 cells and relate the morphological changes to gag-mos induced cellular transformation.NRK-6m2 cell cultures were maintained in McCoy's 5a medium supplemented with 15% fetal calf serum. Subconfuluent cells were washed twice in cold phosphate buffered saline and fixed in situ in 1% glutaraldehyde, scraped and centrifuged at 1500 g for 5 min at 4°C, post fixed in osmium tetroxided and processed for electron microscopic study. Silver sections were stained with uranyl acetate and lead citrate and examined on a Joel 1200 EX electron microscope.
Localization of heavy metals in the hepatopancreas of the terrestrial isopod, Oniscus asellus
Authors: Vernon G. , Greco R. , Witkus R. 
Published: June 2020

Heavy metals have been identified in tissues of a variety of terrestrial isopods exposed to metal polluted sites in Europe. Heavy metals have little effect on some isopods indicating that perhaps the hepatopancreas functions as a detoxifying organ for the isopod by storing the metal. In some lead and copper contaminated rivers tolerant races of the isopod Asellus meridianus were found.Specimens of Oniscus asellus were collected from a cadmium contaminated site adjacent to a marsh in Cold Spring, N. Y. and from an uncontaminated site in New Rochelle, N. Y. Isopods and leaf letter were transported to the lab where some isopods were prepared for scanning electron microscopy (SEM), and others were prepared for atomic absorption spectroscopy. For SEM the hepatopancreatic lobes were fixed in 3,5% glutaraldehyde in 0.1M sodium cacodylate buffer with 0.05% calcium chloride. Specimens were dehydrated in acetone and embedded in Araldite-DDSA. Five micron thick cross sections were deplasticized and gold coated - Sections were viewed and analyzed using an Hitachi S-510 SEM at 25kV with an Ortec 5000 EDX system.
Morphometric analysis of peroxisomes in hepatocytes of alcohol-fed rats
Authors: Dominguez D.C. , Ellzey J.T. 
Published: June 2020

Peroxisomes which participate in 1ipid metabolism have been shown to be altered in several metabolic disorders and toxic conditions. In alcoholic liver disease, the single lesion most frequently found is lipid accumu1ation in hepatocytes. However, the mechanisms for this 1ipid accumu1ation are not clear. The occurrence of modifications of liver peroxisomes due to excess alcohol consumption has not been subjected to a controlled study. We utilized a combination of cytochemica1 and morphometrictechniques to study the size and number of liver peroxisomes in rats fed an alcohol-supplemented diet compared to those of matched-paired control animals.Male Sprague-Daw1ey rats (400-500 g) received a liquid diet. The experimental group (N = 5/group) was fed a diet containing 30% ethanol-derived calories (EDC) and the control group was fed an isocaloric diet to 30% EDC. A pair feeding procedure was employed to control for caloric intake. Small pieces of liver randomly selected, were fixed in 2.3% -glutaraldehyde in 0.1 M sodium cacodylate buffer, pH 7.2, incubated in a DAB medium and postfixed with. 2% aqueous osmium tetroxide. EM photographs were taken from sections of 3 tissue blocks from each sample (7,200X) with a Zeiss EM10-A (60 kV). With the use of a point counting method and a digital planimeter the volume density (Vv) and numerical density (Nv) were determined.
A high-resolution membrane probe
Authors: Hainfeld James F. , Lipka James J. , Elsie Quaite F. 
Published: June 2020

Labeling the lipids of membranes for E.M. is frequently done by using radioactive phospholipids. Membrane dynamics can then be followed by autoradiography. Unfortunately, it takes approximately 6 months to expose the emulsion due to the low specific activity of the labels. Also, the resolution is limited to about 0.2 μm by this technique.An alternative is to develop a phospholipid-like molecule that is electron dense and could be visualized directly. Several such molecules have been synthesized and one is shown in Fig. 1. They have a phosphotungstate “head” group that has a 4 (-) charge and is hydrophilic and an aliphatic “tail” of varying length that is hydrophobic. The tungstate cluster contains 11 tungsten atoms in the “Keggin” structure with a 1.0 nm diameter and has previously been studied in the electron microscope. It was shown to be almost completely resistant to beam induced mass loss.
The extracellular matrix of echinoderm and amphibian eggs: Visualization in quick-frozen, deep-etched, and rotary-shadowed specimens
Authors: Bonnell Barry , Larabell Carolyn , Chandler Douglas 
Published: June 2020

Eggs of many species including those of echinoderms, amphibians and mammals exhibit an extensive extracellular matrix (ECM) that is important both in the reception of sperm and in providing a block to polyspermy after fertilization.In sea urchin eggs there are two distinctive coats, the vitelline layer which contains glycoprotein sperm receptors and the jelly layer that contains fucose sulfate glycoconjugates which trigger the acrosomal reaction and small peptides which act as chemoattractants for sperm. The vitelline layer (VL), as visualized by quick-freezing, deep-etching, and rotary-shadowing (QFDE-RS), is a fishnet-like structure, anchored to the plasma membrane by short posts. Orbiting above the VL are horizontal filaments which are thought to anchor the thicker jelly layer to the egg. Upon fertilization, the VL elevates and is transformed by cortical granule secretions into the fertilization envelope (FE). The rounded casts of microvilli in the VL are transformed into angular peaks and the envelope becomes coated inside and out with sheets of paracrystalline protein having a quasi-two dimensional crystalline structure.
The mechanism of male infertility
Authors: Liankai Dang 
Published: June 2020

There are two types of male infertilities in experimental animals including humanbeing. The first is a man-made infertility for the purpose of contraception; the second is caused by disease which could damage the spermatogenesis. According to the source of pathology, it can be divided into internal infertility and external infertility. Some of invironmental factors such as γ-ray, x-ray, nutron, micro wave and soon and also some of chemical factors could induce the disorder of spermatogenesis, sperms lost the ability for the fertilization or even disappear, Internal sourse means genetic disease or reproductive disease, in that cases the micro invironment for spermatogenesis is disordered; so there are a lot of abnormal sperms in the semen which could not perform the function for the fertilization.The purpose of this paper is to collect all experimental results what we haved one in the past, to compare them and to try finding out changes in commonand difference among them.
High-Resolution SEM and Freeze Fracture Studies of Human Retina
Authors: Szczesny Piotr J. , Claugher Don 
Published: June 2020

The fine structure of human retinae were investigated with use of TEM and High Resolution SEM combined with freeze fracture and osmium maceration technique paying partic ularattention to the morphology of photo receptor cells. Gluteraldehyde fixed retin al samples from 8 individuals of different age groups, were examined. Fixation time varied from 0 to 3 hours post mortem.Results showed good corelation between the TEM and HRSEM Fig 1-2. HRSEM enabled a detailed study of a several plasma membrane domains of rods and cones. It was possible to examine the inner limiting membrane formed by podocytes of Muller cells Fig 3, and also the cell junctions formed by rods, cones and Muller cells at the level of the outerlimiting membrane, Fig 4. HRSEM demonstrated particularly well the area of the photorecept or connecting cilium and the proximal portion of the outer segment in photoreceptors.
Effects of Antihypertensive Drug Treatments on Cerebral Arteriolar Structure and Function
Authors: Ghoneim Shams , Hajdu Michael , Siems Jay , Baumbach Gary 
Published: June 2020

Cerebral arterioles undergo hypertrophy and become more distensible during chronic hypertension(1). These changes are accompanied by a disproportionate increase in volume density of the more distensible components of the arteriolar wall(2). We have recently demonstrated that antihypertensive therapy with hydralazine or an angiotensin converting enzyme (ACE) inhibitor (cilazapril) prevented hypertrophy of cerebral arterioles(3). In addition, cilazapril, but not hydralazine prevented the increase in cerebral arteriolar distensibility that accompanies hypertension(4). The goal of this study was to determine whether treatment of hypertension with either hydralazine or cilazapril caused alterations in the composition of the walls of cerebral arterioles.We studied pial arterioles in 6 month old, stroke-prone, spontaneously hypertensive rats(SHRSP). 24 SHRSP were randomly divided into 3 groups of 8 animals. The first group received Cilazapril(10mg/Kg/day) in its drinking water. The second group received Hydralazine (100 mg/Kg/day) in its drinking water. The third group was left untreated as a control.
Confocal Scanning Slit Microscopy using a Linear Detector Array
Authors: Plant Randall L. , Burns David H. 
Published: June 2020

Confocal microscopy has been shown to produce improved lateral and axial image resolution compared with conventional microscopy. Image degradation due to scattering is reduced since only those portions of the specimen in the focal plane of the objective will contribute to image formation at the light detector. Previous work has shown that slit apertures can be used instead of pinholes to achieve the advantages of confocal microscopy with increased illumination and deceased scan line artifact. Slit scanning microscopes are also simpler in design than pinhole scanners but their aperture forms an asymmetric point spread function. We have developed a confocal scanning microscope utilizing a slit aperture and a linear charge coupled device (CCD) as a photodetector. We characterize its resolution for imaging a thick luminescent specimen as a function of scanning axis, wavelength, and tissue depth.A schematic of the new confocal microscope is shown in figure 1. The illumination source is a 150 watt incandescent bulb.
The Quantitative Ultrastructure of the Heart Muscle of Japanese Quail by Hypergravitation, Hypodynamy and Combination
Authors: Bózner Anton , Gažo Mikuláš , Dostál Jozef 
Published: June 2020

It is anticipated that Japanese quail /Coturnix coturnix japonica/ will provide animal proteins in long term space flights. Consequently this species of birds is of research interest of international space program INTERCOSMOS. In the year 1987 we reported on an experiment /2/ in which the effect of chronic acceleration of 2 G hypergravitation, the hypodynamy and the simultaneous effect of chronic acceleration and the location in the centre of the turntable of the centrifuge on the protein fractions in skeletal muscles was studied. The ultrastructure of the heart muscle was now in this experiments examined as well.Japanese quail cockerels, aged 48 days were exposed to 2 G hypergravitation /group IV/ in a 6,4 m diameter centrifuge, to hypodynamy /group III/ and their combination /group V/, respectively for 6 days / Fig.1/. The hypodynamy in group III was achieved by suspending the birds in jackets without contact the floor. The group II was located in the centre ofthe turntable of the centrifuge. The control group I. was kept under normal conditions. The quantitative ultrastructure of myocard was evaluated by the methods of Weibel/3/ - this enables to determine the number, relative size and volume of mitochondria volume of single mitochondria, defficiency of mitochondrial cristae and volume of myofibrils.
Microtubule Dynamics and Organelle Transport in Reticulomyxa
Authors: Chen Yih-Tai , Euteneuer Ursula , Johnson Ken B. , Koonce Michael P. , Schliwa Manfred 
Published: June 2020

The application of video techniques to light microscopy and the development of motility assays in reactivated or reconstituted model systems rapidly advanced our understanding of the mechanism of organelle transport and microtubule dynamics in living cells. Two microtubule-based motors have been identified that are good candidates for motors that drive organelle transport: kinesin, a plus end-directed motor, and cytoplasmic dynein, which is minus end-directed. However, the evidence that they do in fact function as organelle motors is still indirect.We are studying microtubule-dependent transport and dynamics in the giant amoeba,Reticulomyxa. This cell extends filamentous strands backed by an extensive array of microtubules along which organelles move bidirectionally at up to 20 μm/sec (Fig. 1). Following removal of the plasma membrane with a mild detergent, organelle transport can be reactivated by the addition of ATP (1). The physiological, pharmacological and biochemical characteristics show the motor to be a cytoplasmic form of dynein (2).
Ultrastructural comparison of amyloid-like glyomerulopathy
Authors: Caughey R.C. , Kelly C.E. 
Published: June 2020

Without transmission electron microscopy cases of amyloidosis-like glomerulopathy may be erroneously considered to be amyloidosis, diabetic or membranous nephropathy. Mesangial widening and increased matrix, and capillary basement membrane thickening are features common to amyloid-like glomerulopathy, amyloidosis, and diabetic renal problems. Amyloid-like immunofluorescence may be positive for IgG, and C3 within the mesangium and capillary walls suggesting possible membranous nephropathy. Some cases appear to represent light chain nephropathy, which is known to result in crystalline-like ultrastructural deposits. Identification of amyloid-like glomerulopathy is made by Congo Red negativity and characteristics of ultrastructural fibrils.The renal biopsies from all patients were fixed in 2.5% glutaraldehyde, rinsed in Millonig’s phosphate buffer, and post fixed in 1% osmium tetroxide. They were then en bloc stained with 1% uranyl acetate, rinsed with Walpole’s non-phosphate buffer, dehydrated with a graded series of ethanols and embedded with Epon 812 epoxy resin. Ultramicrotomy thin sections were post-stained with uranyl acetate and lead citrate and scanned using a JEOL JEM 100C.
Dermatopathia Pigmentosa Reticularis
Authors: Bielenberg U. , Burns W. , Clark Lambert W. , Schwartz R.A. , Marquet E. 
Published: June 2020

Dermatopathia pigmentosa reticularis (DPR) is a reticulate pigmentary disorder of as yet unclear inheritance that was first described in 1958. Since then only an additional eight cases have been reported, all in the European literature. To our knowledge, this is the first case from the United States of America and the first with an ultrastructural study.The patient is a 44-year-old man of mixed Black, Hispanic and American Indian descent with generalized, variably pigmented skin over the entire body present since birth.A punch biopsy of pigmented forearm skin was taken for light microscopy which demonstrated hyperkeratosis, an intact granular layer, and epidermal atrophy with focal liquefaction degeneration of the basal cell layer. The dermis showed pigment incontinence. Direct immunofluorescence was negative for immunoglobulins and complement at the basement membrane zone. A second skin biopsy of an elbow plaque showed the above changes except for the alteration of the basal layer.
Study of Wheals on Gastric Mucosa in Patients with Chronic Uticaria by Scanning and Transmission Electron Microscopy
Authors: Wang Jianhua , Hu Shaopeng , Chu Fei , Sun Shegzheng , Zhang Jinzhang 
Published: June 2020

Urticarial wheal is due to the leak of proteins and fluids to extravascula by increased capillary permeability. Edematous erythema and wheals located in the surface of gastric mucosa were observed by gastroscopy. The present contribution is the first in the international extent of the observation of wheals on gastric mucosa of 38 patients with chronic urticaria with the transmission electron microscope (TEM) and scanning electron microscope (SEM).Gastroscopies were performed on 38 patients with chronic urticaria during episodes ofcutaneous wheals. Biopsy specimens were taken from gastrical wheals from 38 patients. The EM specimens were routinely prepared. Linder the SEM, the surface of the epithelial cells of wheals on the gastric mucosa appeared slightly edematous and rough. Intercellular space of the epithelium became more narrow and shallow. The structure of microvillae on gastric mucosa epithelial cells could be seen, but appeared short and decreasing in amount. Under the TEM, it was found that the stomach mucous membrane was edematous.
Osmolarity and Artificial Cell Damage in Ischemic Myocardium
Authors: Montione Richard , Ashraf Muhammad 
Published: June 2020

Osmolarity of a fixative vehicle has long been known to have an effect on the tissue preservation. An increase in tissue osmolarity occurs in ischemia-damaged tissue and affects the morphology. In this study, we examined cellular changes in ischemic rat myocardium induced by varying fixative toxicity.Rats were sacrificed by decapitation and the hearts immediately removed and retrogradily perfused through the aorta with anoxic Kurbs-Henseleit medium. Hearts were then placed in a bag with a small amount of medium at 37°C for 90 minutes. Hearts were perfusion-fixed using 2% glutaraldehyde in 0.1 M cacodylate buffer pH -7.3 at three osmolarities. The isotonic buffer was adjusted to 311 mOsm/kg using D-manitol. Hypertonic buffers were adjusted to 375 and 400 mOsm/kg. One-half hour after perfusion fixation, the hearts were sliced and cut into small blocks and allowed to fix overnight at 4°C. Blocks were post fixed in osmium, en bloc stained in uranyl acetate, dehydrated in ethanol and embedded in Spurr medium.
Electron microscopic study of effects of Polyactin A on the colonies cells of spleen
Authors: Xiang Yuan Zeng , Ying Zhang 
Published: June 2020

Electron microscopic studies on the colonies cells of spleen were presented.Polyactin A is a new immunological enhancement agent which was developped in China for the first time. It is a polysaccharide extracted from cultured a-hemolytic streptococcus No. 33 in the mouth. Clinical observation suggests that the drug has marked inhibiting effects on some tumors and can increase the number of leucocytes, enhance immunity of the organism. Polyactin A has also a good effect on aplastic anemia and it is a new drug in treatment of aplastic anemia. However, its mechanism isn't understand.In order to investigation this problem, electron microscopic observation on the colonies cells of spleen (CFU-s) were studied and effects of Polyactin A on hemopoietic stem cell of marrow were also discussed. The results showed that Polyactin A can make marked effects on ultrastructures of colonies cells of spleen (CFU-s). Stem cells dilated and nucieus showed inregularity in shape. Chromatin in the nucleus which has enlarged nucleolus was compact and euchromatin increased. There were abundant organelles such as rough endoretigrum, ribsomes and mitochondria in the cytoplasma.
Cell biological studies of primary and metastatic tumors of the rat prostate
Authors: Heidger Paul M. , Kutschke William J. , Bataineh Ziad 
Published: June 2020

The widespread occurrence and high mortality rate in older men associated with disseminated adenocarcinoma of the prostate provide a strong impetus for basic studies of the normal and neoplastic prostate gland. The present studies have been undertaken with the objective of gaining a fuller appreciation of histo- and cytologic interrelationships between metaplastic prostatic tumors and their host organs.The Dunning rat adenocarcinoma has provided a model for some years for the study of primary prostatic tumors, and recently a tumor subline has been identified which preferentially metastasizes to lung (Dr. David M. Lubaroff, U. IA). Cells of the metastatic subline colonize lung following intravenous injection, and produce widespread lesions within the lung parenchyma, and deep to the visceral pleura, in a matter of weeks. Correlative light microscopic (LM), transmission (TEM) and scanning (SEM) electron microscopic studies have been conducted of both the primary Dunning tumor, and the metastatic lesions within lung, using routine preparative techniques. Morphological examination has been conducted in concert with immunocytochemical localization of components of the extracellular matrix, within both lung and tumor, and with studies of the growth and attachment characteristics of tumor cells cultured in wells coated with such extracellular matrix components as fibronectin, laminin, and collagen types I and IV.
Ultrastructural characterization of cytomegalovirus infected and interferon producing human foreskin cells
Authors: Rodriquez J. , Moninger T.O. , Walker D. , Moore K. C. 
Published: June 2020

Published work indicates that human cytomegalovirus (CMV) is sensitive to the action of beta interferon (HuIFNb) and can induce the production of INF in cultures of human foreskin (HF) cells. These findings are consistent with a role for endogenous IFN in the establishment and maintenance of persistent CMV infections. Moreover HF cells can be primed with IFN and these primed cells can be induced to produce large concentrations of IFN after exposure to CMV. These findings support the hypothesis formulated to explain the larger-than-expected concentrations of IFN detected in cultures exposed to low MOIs (<0.01), namely, that the phenomenon observed involved endogenous priming, that is production of IFN by the small percentage of the cells infected by the inoculum virus. This results in priming of the remaining cells by IFN, and finally induction of the primed cells by progeny CMV released from the cells infected originally.To lend support to this hypothesis we will follow the attachment, penetration, and release stages of the CMV replication by transmission and scanning electron microscopy.