bluuebunny/crossref_metadata_2025_split huggingface dataset:
Observation of basal cells in the olfactory epithelium after axotomy
Authors: Suzuki Yuko , Takeda Masako 
Published: June 2020

In the olfactory epithelium of mice, cytokeratin was present in the basal cells but not in the olfactory cells. Our previous study using antikeratin antibodies showed that the basal cells were columnar or pyramidal in shape in the early postnatal period, but became flat in adult mice. In this study, structural changes of the basal cells after axotomy were investigated by immunohistochemistry, transmission electron microscopy (TEM), and scanning electron microscopy (SEM).The unilateral olfactory nerves of adult mice were sectioned at the level of the lamina cribrosa. The mice were sacrificed 4, 8-10, and 14 days postoperatively. The olfactory mucosae were removed, frozen with freon 22, and cut on a cryostat at 10 μm. The sections were stained by the PAP method using a PAP kit. The antikeratin antibody (PKK 2) against pig kidney epithelial cell line, which reacts with 40, 46, 48, and 54 kd subunits (Immunotech), was used. To label the dividing cells, bromodeoxyuridine (BrdU) was administered to mice each postoperative day 1 hour before sacrificing. The presence of BrdU was detected imrnunohistochemically using anti-BrdU antibody (Becton-Dickinson).
Comparative study of ultrastructure of HIV and SIV
Authors: Nakano Takashi , Imura Shunro , Nakai Masuyo 
Published: June 2020

The ultrastructural feature of AIDS viruses (HIV and SIV) was observed by ultrathin-sectioning and negative staining method, and the surface structures of these viruses were compared.HIV-1 group including, HTLV-III and LAV-1 were used. And in HIV-2 group, LAV-2, which was isolated from a Senegalese AIDS patient, and GH-1, which was isolated from a Ghanan AIDS patient, were used. SIV group was used AGM-1, which was isolated from an African green monkey. The virions were used which was produced from Molt-4 cells after the infection of each viruses of these strains. The infected cells and viral particles, which were collected by centrifugation were fixed with 2% glutaraldehyde (GA), washed with PBS, and postfixed with 1% osmium tetroxide. The specimens were dehydrated in graded ethanol, and embedded in Epon 812. The thin sections were stained with uranyl acetate and lead citrate. On the other hand, for negative staining, 25% GA was added to the supernatant culture fluid and finally concentrated on 2% GA. Then virions were collected by ultracentrifugation.
The effects of Cyclosporin-A (CYA) on the Ultrastructure of Gingival Mast Cells (GMC) in Behcet's disease (BD)
Authors: Arda Oktay , Noyan Ulkü , Yilmaz Selgçk , Taşyürekli Mustafa , Seçkin İsmail , Yılmazer Selma , Satıroğlu Güngör 
Published: June 2020

Turkish dermatologist, H. Beheet described the disease as recurrent triad of iritis, oral aphthous lesions and genital ulceration. Auto immune disease is the recent focus on the unknown etiology which is still being discussed. Among the other immunosupressive drugs, CyA included in it's treatment newly. One of the important side effects of this drug is gingival hyperplasia which has a direct relation with the presence of teeth and periodontal tissue. We are interested in the ultrastructure of immunocompetent target cells that were affected by CyA in BD.Three groups arranged in each having 5 patients with BD. Control group was the first and didn’t have CyA treatment. Patients who had CyA, but didn’t show gingival hyperplasia assembled the second group. The ones displaying gingival hyperplasia following CyA therapy formed the third group. GMC of control group and their granules are shown in FIG. 1,2,3. GMC of the second group presented initiation of supplementary cellular activity and possible maturing functional changes with the signs of increased number of mitochondria and accumulation of numerous dense cored granules next to few normal ones, FIG. 4,5,6.
Various microtubular patterns in dorsal root ganglia (DRG) in pyridoxine neurotoxicity
Authors: Montpetit V.J.A. , Dancea S. , Tryphonas L. 
Published: June 2020

The term “microtubule” (MT) has been ascribed to a complex group of subcellular structures deploying at least two common characteristics: a hollow cylindrical shape and a diameter of less than 30 nm. Some authors, however, regard MT as composed of tubulin with well known roles in the organization of the cytoskeleton and different cellular functions such as secretion, mitosis, and motion. In alteration of the neuronal cytoskeletal organization in neurotoxicity, their tubulin composition has usually been unquestioned. Recently observed unusual MT aggregation patterns in pyridoxine neurotoxicity definitely raised questions as to the composition of some of the groups of microtubules which fulfill the general definition. At least three different patterns of MT aggregations were seen in neuronal cytons of DRG of dogs treated with high doses of pyridoxine.The large MT aggregates made up of numerous superimposed sheets of MT in parallel arrays and having different orientation in close proximity to ribosomes and membranes of rough endoplasmic reticulum (RER) have already been reported.
Evaluation of hippocampus in rhesus monkeys after chronic (1-year) inhalation exposure to marijuana: II. Morphometric methods
Authors: Wilson S.W. , Andrews A.M. , Scallet A.C. , Ali S.F. , Bailey J.R. , Paule H.G. , Slikker W. 
Published: June 2020

An innovative method was used to collect data for morphometric analysis of synaptic measurements. Negatives of the CA3 region of the hippocampus were obtained as described by Andrews et al., 1990, and evaluated by computersupported image analysis. Negatives of 4000X and 40,000X magnification were used to measure synaptic density and width, respectively. The image analysis system (IAS) used an IBM-AT compatible computer with a frame grabber (Imaging Research Inc.). This particular system can measure either straight line distance (rubber line) or curved two point distances (draw line).For synaptic density, the IAS was calibrated in angstroms at a magnification of 4000X. A log file was created for each negative in which the measurement for each synapse was stored. The negative was placed on a transparency with grids 9 mm square to ensure that the entire negative was scanned. The image was displayed on a multicsync monitor using a high resolution camera (Applied Intelligent Systems Inc.). When a synapse came into view, the image was digitized on the monitor (Fig. 1 A and B) and stored in digital form.
Ultrastructure of “putative” neurotransmitter sites in Schistosoms mansoni Miracida
Authors: Ruth Jones Betty , Chi-Tung Pan Steve 
Published: June 2020

Schistosomiasis has been described as “one of the most devastating diseases of mankind, second only to malaria in its deleterious effects on the social and economic development of populations in many warm areas of the world.” The disease is world wide and is probably spreading faster and becoming more intense than the overall research efforts designed to provide the basis for countering it. Moreover, there are indications that the development of water resources and the demands for increasing cultivation and food in developing countries may prevent adequate control of the disease, and thus, the number of infections are increasing.Our knowledge of the basic biology of the parasite causing the disease is far from adequate. Such knowledge is essential if we are to develop a rational approach to the effective control of human schistosomiasis. The miracidium is the first infective stage in the complex life cycle of schistosomes.
Scanning Electron Microscopy of neuronal cell bodies isolated from the adult mammalian central nervous system
Authors: Liu Wenshu , Franklin Bailey J. , Limwongse Visaka , DeSantis Mark 
Published: June 2020

Action potentials generated in a motor neuron reflect the summation of synaptic inputs it receives from other neurons. Those synapses occur at points of contiguity between the presynaptic boutons and the surface of the motor neuron. Evidence that the density of axosomalic boutons on motor neurons varies directly with the size of the motor neuronal soma is indirect. Counts of the number of boutons per unit area at the surface of the motor neuron’s cell body using scanning electron microscopy (SEM) would allow an independent, direct assessment of that inference. We describe here procedures for consistently isolating the somas of CNS neurons, specifically those associated with the adult rat’s trigeminal nerve, so that axosomatic boutons can be seen by SEM (Figures 1 and 2).Adult male and female rats were anesthetized and then perfused with saline followed by 4% paraformaldehyde. The brain stem was removed and sectioned at 200 um thickness on a vibratome. Sections containing the trigeminal motor and mesencephalic nuclei were pinned to Sylgard-lined dishes containing phosphate buffer (0.1 M, pH 7.2).
Elastic behavior and arrangement of titin filaments in the I-band
Authors: Trombitás Károly , Pollack Gerald H. , Wright John , Wang Kuan 
Published: June 2020

Immunoelectron microscopic studies have revealed that the I-band domain of the titin filament behaves elastically. We report experiments that suggest that titin forms independent, highly elastic filaments in the I-band, except in the N1-line region near the Z-line.Freshly prepared bundles of rabbit psoas muscle fibers were quickly frozen and broken into small pieces under liquid nitrogen to fracture sarcomeres at the I-band region. The still-frozen specimens were thawed during fixation with paraformaldehyde (3.7%) in PBS to allow elastic filaments to retract. The muscle pieces were then labelled with monoclonal anti-titin (RT 13 and Sigma), followed by treatment with second antibody (goat anti-mouse).This method gave an excellent decoration pattern. The position of the titin epitope is symmetrical relative to the Z-line (Figure 1). However, in regions where the sarcomeres were broken at the A-I junction, the epitopes are no longer symmetrical about the Z-line (Figure 2); the broken thin filaments remained in their original position, but the titin filaments in the broken half retracted, independently of the thin filaments, forming a dense band just near the Zline (arrow).
Ultrastructural study of the filamentous pelvic fins of the anabanthid fish Trichogaster trichopterus
Authors: Fanta E. , Eiras-Stofella D. R. , Mehler B. , Ortolani C. F. 
Published: June 2020

As have many other Anabanthid fish, Trichogaster trichopterus has filiform modified pelvic fins. In this species they are used for equilibrium or for communication between individuals, in a deliberate sequence of movements, as could be observed. Like true barbels, they seem to detect through taste, mainly acidity.Through SEM and TEM it was possible to describe the structures that are responsible for these varied uses of the “barbels.” Fixation was in glutaraldehyde 2.5% in 0.2M phosphate buffer, and post fixation in 1% osmium tetroxyde, in the same buffer. For SEM the dehydration was in a graded ethanol series, and the critical point was reached with liquid CO2; the coating was with gold. A Philips TEM and Philips SEM were used.The epithelium is stratified; the cells are well fixed through cell junctions, and with frequent interdigitations (Fig. 3). The outer layer has light polygonal cells, with external concentric ridges (Fig. 1). A second type of darker cells can also be observed. Many taste buds are observed, mainly from the median to the top region (Fig. 1).
Ultrastructural observations on hemocytopoiesis in embryos of the horseshoe crab, Tachypleus tridentatus
Authors: Liang Ping , Cheng Ting-Kai , Wu Yi-qin , Wu Wei-hong 
Published: June 2020

The main type of horseshoe crab hemocytes is amebocyte (granulocyte), whose lysate is a very sensitive indicator of endotoxin, and has been used widely in the medical and pharmaceutical fields. The origin, site of production and course of development of amebocyte haven’t been solved yet. It is still in dispute if there is another cell type in the circulating hemolymph. We have studied the fine structure of amebocytes from adult Tachypleus tridentatus, and found a small number of immature and maturing amebocytes, a few being in mitosis, and considered these findings to be full proof that some amebocytes could proliferate and mature during circulation. This paper represents a continuation of our previous work, and reports the observations on hemocytopoiesis in embryos of Tachypleus tridentatus.The embryos were obtained by artificial insemination and incubation. The specimens for light microscopic studies consisted of 17 embryos 13-21 days old, 3 embryos and 3 trilobite larvae shortly before and after hatching, while those for electron microscopy included 6 embryos of 13-19 days, 1 late embryo and 1 trilobite larva. All specimens were processed in a routine manner.
The variations of virus shape and size in different preparations
Authors: Mingxiao Ding , Renjie Jiao , Fengxia Liang , Zhonghe Zhai 
Published: June 2020

Envelope is a very important structure for viral attachment and entry into the host cell, but it is also a morphologically variable portion of enveloped viruses. Studying the fine structure of enveloped viruses, we noticed that different sample preparations of viruses resulted in the change of viral size and shape to some extent, which we believe was caused by the variation of the viral envelope. Four typical enveloped viruses: IBRV (Infectious Bovine Rhinotracheitis Virus), GPV (Goat Pox Virus), SbV (Sindbis Virus) and VSV (Vesicular Stomatitis Virus) were investigated in our experiments.Host cells infected with IBRV, GPV, SbV and VSV respectively were fixed with 1-5% glutaraldehyde in Hank's buffer when the cytopathic effects appeared in 50-70% of the cells, then the specimens were treated respectively with different conventional methods of EM sample preparation: 1) ultrathin sectioning, 2) negative staining,3) freeze etching, 4) surface replica, 5) whole mount or SEM observations. All the samples were examined under JEM-200CX TEM or JSM-35CF SEM.
Ultrastructural study on surface components of Streptococcus suis
Authors: Jacques Mario , Gottschalk Marcelo , Foiry Bernadette , Higgins Robert 
Published: June 2020

Streptococcus suis is an important pathogen in pigs. To the best of our knowledge, surface components of S. suis have not been studied. As part of our work dealing with the characterization of S. suis virulence factors, we examined the surface components of nine reference strains. Bacterial capsules are composed of highly hydrated polymers, usually polysaccharides. Because of their chemical properties, they can collapse during dehydration prior to electron microscopy. Jacques and Graham have recently introduced a modified aldehyde fixation process in which addition of a primary amine was found to improve the preservation of bacterial capsule.Reference strains representing serotypes 1 through 8, and ½ of S. suis were grown on blood agar plates for 18 h at 37°C. Bacteria were harvested and washed once with phosphate buffered saline (PBS, 0.01M, pH 7.2).
Distribution of dihydrofolate reductase-thymidylate synthetase polypeptide in methotrexateresistant and wild type Leishmania major: Evidence for cytoplasmic distribution despite a hydrophilic leader sequence
Authors: Swafford J. R. , Beverley S. M. , Kan C. C. , Caulfield J. P. 
Published: June 2020

The housekeeping enzymes, dihydrofolate reductase (DHFR) and thymidylate synthetase (TS) are encoded by separate genes and located in the cytoplasm of higher eukaryotes. However, in the trypanosomatid protozoan Leishmania these enzymes are both located on a single polypeptide. The DNA sequence for this polypeptide predicts a 23 hydrophilic amino acid extension from the amino terminus that resembles the import sequence of mitochondrial proteins in other species. It is not known whether the hydrophilic leader actually occurs in the mature protein in Leishmania since the amino terminus is blocked.Here, we have examined the distribution of the DHFR-TS peptide in two strains of Leishmania major in order to see if there was a preferential distribution of the protein in the mitochondrion.
Ultrastructural studies on the pheromone gland of Exorista sorbillans (Weidman): A serious pest of silkworms
Authors: Akbar M. , Jamil Kaiser 
Published: June 2020

Calling behaviour in several insect species has been related to the volatile chemicals produced and released from specialised glands in the abdominal region of the adult insects. These chemicals comprising generally of about 13-24 carbon straightchain compounds with active cis and trans positions, known as pheromones, are produced from specialised cells located on pheromone gland. in view of the importance of these cellular structures ultrastructural studies were carried out. These glands were found to be located on the ovipositor of the female fly.The heptane washings of the ovipositors of the female flies induced behavioural response in male flies when bioassayed. Having confirmed the presence of the chemical eliciting behavioural response, it was found important to locate the gland producing these chemicals.
Freeze-substitution of rye grass and ragweed pollen grains
Authors: Martinez Liza B. , Wick Susan M. 
Published: June 2020

Rapid freezing and freeze-substitution have been employed as alternatives to chemical fixation because of the improved structural preservation obtained in various cell types. This has been attributed to biomolecular immobilization derived from the extremely rapid arrest of cell function. These methods allow the elimination of conventionally used fixatives, which may have denaturing or “masking” effects on proteins. Thus, this makes them ideal techniques for immunocytochemistry, in which preservation of both ultrastructure and antigenicity are important. These procedures are also compatible with cold embedding acrylic resins which are known to increase sensitivity in immunolabelling.This study reveals how rapid freezing and freeze-substitution may prove to be useful in the study of the mobile allergenic proteins of rye grass and ragweed. Most studies have relied on the use of osmium tetroxide to achieve the necessary ultrastructural detail in pollen whereas those that omitted it have had to contend with poor overall preservation.
Anatomy and ultrastructure of haustoria in selected West Australian parasitic angiosperms
Authors: Kuo John , Pate John S. 
Published: June 2020

Our understanding of nutrient transfer between host and flowering parasitic plants is usually based mainly on physiological concepts, with little information on haustorial structure related to function. The aim of this paper is to study the haustorial interface and possible pathways of water and solute transfer between a number of host and parasites.Haustorial tissues were fixed in glutaraldehyde and embedded in glycol methacrylate (LM), or fixed in glutaraldehyde then OsO4 and embedded in Spurr’s resin (TEM).Our study shows that lumen to lumen continuity occurs between tracheary elements of a host and four S.W. Australian species of aerial mistletoes (Fig. 1), and some root hemiparasites (Exocarpos spp. and Anthobolus foveolatus) (Fig. 2). On the other hand, haustorial interfaces of the root hemiparasites Olax phyllanthi and Santalum (2 species) are comprised mainly of parenchyma, as opposed to terminating tracheads or vessels, implying that direct solution transfer between partners via vessels or tracheary elements may be limited (Fig. 3).
Osmium tetroxide vapor fixation for preserving fungal structures for SEM
Authors: Tiedt L.R. 
Published: June 2020

Scanning electron microscopy has provided valuable information in studies of fungal morphology and ontogeny, but undisturbed preservation of sporulating structures is often difficult.In this study of sporodochia development in Fusarium spp. in the section Liseola, the usual method of aqueous fixation, dehydration and the subsequent critical-point drying method, could not be used. Macroconidia forms sporodochia by means of water soluble slime and when aqueous solutions come in contact with the sporodochia, the conidia become scattered. To preserve these morphological structures, the samples had to be vapour fixed with osmium tetroxide. Sample blocks were excised from the sporulating cultures and carefully transferred to the inner surface of a Petri dish cover. The cover with several adherent agar blocks were inverted over a Petri dish bottom containing several drops of 2% osmium tetroxide. The Petri dish was left at room temperature for 24h. The Petri dish cover with the fixed samples was transferred to a clean Petri dish bottom and left to air dry.
Electron Microscopic study of dipteran Halteres by using preserved specimens
Authors: Grewal J. S. , Kapoor V.C. , Kochar J. 
Published: June 2020

Halteres, highly specialized metathoracic wings are the balancing organs in Diptera. This is probably an adaptation for aerial swarming. Our understanding regarding the detailed structure of this organ is very little. An effort has been made to study the ultrastructure of halteres and the functional aspects of various parts have been discussed.Flies are relaxed in relaxing medium (Watkins and Doncaster Hawkhurst, England) or by keeping overnight in 50% ethanol. Halteres alongwith a little of thorax lateral wall are peeled off with the help of fine and sharp scalpel. These are boiled in distilled water for about 20 minutes to get rid off all the distortion of structure due to preservation. A fungal growth observed on the material is cleared off by putting a drop or two of phenol in boiling water. Material is then subjected to sonication in distilled water to remove any foreign particle adhering to halteres. Then the material is dehydrated by passing through ethanol series.
Analysis of cathodoluminescence emitted from lipid droplets in corpora lutea of estrus cyclic and pregnant rat by analytical color fluorescence EM
Authors: Ning Gang , Nakano Tohru , Fujimoto Toyoshi , Koike Hirotami , Ogawa Kazuo 
Published: June 2020

We developed an analytical color fluorescence electron microscope (ACFEM), which enabled us to detect strong cathodoluminescence (CL) emitted from lipid droplets (LD) in various cells. In previous studies, we demonstrated that steroids and retinoids are most likely to be the chemical components emitting CL. In the present research, we examined CL in corpora lutea (CpL) of rats at various stages of the estrus cycle and gestation by ACFEM.Adult female Wistar rats either following a normal estrus cycle or pregnant were either decapitated or anesthetized by sodium pentobarbital and the ovary was excised and cut into small pieces. The tissue was attached to aluminium sample tips, rapidly frozen by liquid propane cooled in liquid nitrogen without chemical fixation and cut with a cryo-ultra microtome to make a flat surface for observation. The specimens were kept at -100°C on a cryo-stage and observed by an ACFEM constructed on a basis of a high resolution scanning electron microscope (AKASHI DS-130).