bluuebunny/crossref_metadata_2025_split huggingface dataset:
The use of ultracryotomy to localize sites of activity of endogenous and exogenous enzymes in plant cells
Authors: Vian B. , Roland J. C. 
Published: June 2020

During the recent years ultracryotomy revealed as a technique suitable for the study of plant cells. The main advantages are that the tissues support the minimum of chemical modifications and that the sections retain enzymatic activities. On an other hand, since the sections are devoided of plastic embedding, problems of penetration are eliminated. The sections are hydrophilic and directly accessible to reactives Therefore it seems possible to perform a wide range of enzymatic attacks at this level.Both aspects were investigated for different cases previously studied with conventional methods and for which some technical problems remained unsolved. For example, the attack of wall components is difficult to perform, even when the specimens are embedded in more or less hydrophilic resins.Attempts were made on adult leaves of spinach and mung bean hypocotyls prepared for ultracryotomy according to Tokuyasu. The specimens were prefixed (lh, 4°C) in 1 - 3% glutaraldehyde, infused (10-20 min, 4°C) in 1. 5 M sucrose, frozen in liquid nitrogen or supercooled nitrogen and sectioned at - 80°C on a Sorvall MT2 microtome fitted with a cryokit FTS.
Electron microscopic study on the phagocytic lining cells in the cavernous body of the lamprey gill
Authors: Yamaguchi Kazuhito , Awaya Kazuhiko 
Published: June 2020

The lining cells in the cavernous body, which is a branch of the afferent branchial artery, of lamprey gills were studied with transmission (TEM) and scanning electron microscope (SEM).Adult and larval lampreys, Lampertra planeri, were used in this study. Lamprey gills removed after perfusion were fixed in 2 % glutaraldehyde/formaldehyde (pH 7. 4) for 1 hour and postfixed in 1 % osmic acid. For TEM, the gills were dehydrated in ethanol and embedded in epon 812. Ultrathin sections were doubly stained with uranyl acetate and lead citrate. For SEM, most of the gills were dehydrated in ethanol and isoamylacetate and cracked in liquid nitrogen. Some of the gills dehydrated were embedded in stylene monomer. Stylene embedded blocks were cracked with a hummer and dissolved in propylene oxide. All the specimens were dried in a critical point dryer and coated 100 Å thickness with gold-paladium.The cavernous body is composed of trabeculae, between which are blood spaces, the lacunae.
Morphology of vascular smooth muscle cells and pericytes as revealed by transmission and scanning EM
Authors: Uehara Y. , Komuro T. , Desaki J. 
Published: June 2020

Although subcellular organization of vascular smooth muscle cells and pericytes have been described by a number of authors, the precise overall structure of these cells has not been revealed at the fine structural level.In order to extend our knowledge in understanding of vascular function, the present paper deals the three dimensional organization of these cells as studied with a transmission EM using serial sections and with a scanning EM using materials from which connective tissue elements are removed.For the reconstruction study, arterioles ranging in diameter from l0um to 25um are selected from the hamster skeletal muscle and the rat pancreas.Fig. 1. demonstrates an example of the reconstructed model of the arteriole smooth muscle cell. Here the muscle cell takes a spiral form which coils nearly twice around the endothelial column. The shape and disposition of the muscle cells gradually become to be irregular towards the capillary bed.
Hemoglobin crystals of the red blood cells in the human renal cortex: electron microscopic observations of the renal lithiasis
Authors: Ueda Kosuke , Washida Hiroto , Watari Nakazo 
Published: June 2020

IntroductionHemoglobin crystals in the red blood cells were electronmicroscopically reported by Fawcett in the cat myocardium. In the human, Lessin revealed crystal-containing cells in the periphral blood of hemoglobin C disease patients. We found the hemoglobin crystals and its agglutination in the erythrocytes in the renal cortex of the human renal lithiasis, and these patients had no hematological abnormalities or other diseases out of the renal lithiasis. Hemoglobin crystals in the human erythrocytes were confirmed to be the first case in the kidney.Material and MethodsTen cases of the human renal biopsies were performed on the operations of the seven pyelolithotomies and three ureterolithotomies. The each specimens were primarily fixed in cacodylate buffered 3. 0% glutaraldehyde and post fixed in osmic acid, dehydrated in graded concentrations of ethanol, and then embedded in Epon 812. Ultrathin sections, cut on LKB microtome, were doubly stained with uranyl acetate and lead citrate.
Ultrastructure and derivation of the alveolar brush cell
Authors: Hijiya Kazuyuki 
Published: June 2020

In the alveolar lining layer of the rat lung, besides the well documented two types of alveolar epithelical cell (Types I and II), the third epithelial cell (alveolar brush cell or Type III cell) has been found by Meyrick. Fine structure of alveolar brush cell and its relationship with Type I and II cells were investigated using a transmission, and especially a scanning electron microscope (TEM, SEM).Materials and Methods.Ninety—five male rats of the Wistar strain were injected intraperitoneally with lOmg/kg/day body weight of Bleomycin sulfate for 31 successive days. Another sixty male rats of the same strain ranged from 1 week to 20 weeks in age were also used. The animals were sacrificed under deep Ketalar anesthesia chronologically after treatment. The preparation of the lung specimens for TEM and SEM was carried out in the same way as described previously. TEM observations were made with an Akashi S500 electron microscope, and SEM observations were made with a Hitachi HFS-2S field emission source scanning electron microscope.
Human fetal lung organotypic cultures preserved by lipid-carbohydrate retaining methods
Authors: Stratton C. J. , Douglas W. H. J. , McAteer J. A. 
Published: June 2020

Surfactant studies in general, and particularly those on the type II cell are hindered by the intrinsic cellular heterogeneity and structural complexity of the lung. Indeed, electron microscopic investigations of the lung encounter problems with both non-uniform sampling, and the technical difficulty of preserving intra- and extracellular surfactant through the dehydration steps. Fetal lung organotypic cultures provide a highly enriched type II cell population in which the in vivo cellular relationship of an intact epithelial-mesenchymal interface is maintained. The new lipid-carbohydrate retaining electron microscopic procedures have been shown to preserve most of the structural components of biomembranes and carbohydrate gels, and thus retain the natural appearance of both intra- and extracellular surfactant.Human fetal lung (18 and 18. 5 weeks gestational age) was: enzymatically dissociated (0. 1% trypsin, 0. 1% collagenase, 1. 0% chicken serum in Moscona's saline); filtered; centrifuged (160 x G for 6 minutes); incubated at 37°C for one hour; resuspended in culture medium (Ham's F12K + 10% FBS); and cultured on a Gelfoam collagen sponge.
Ultrastructural changes in the rat hepatocytes during azo dye carcinogenesis modified by furaciline
Authors: Pinchouk V. G. , Monastyrskaya B. D. , Andrianov V. M. , Nikitchenko V. V. , Bilitch K. M. 
Published: June 2020

Nitrofuran derivatives have been known to have a strong inhibitory effect on azo dye hepatic carcinogenesis when they are fed to rats simultaneously with an azo dye (Miyaki et al., 1969; Miyaji, 1971; Akao et al., 1971). It is assumed that the nitrofurans retarded the induction of hepatomas because they stimulate RNA-polymerase activity of liver nuclei inhibited by azo dye feeding (Akao et al., 1972; 1974)Male rats were fed a rice diet containing 0, 06% 4-dimethylamino- azobenzene (DAB) and 0, 2% furaciline /semicarbason-5-nitrofurfurole/ (F6) for 6 months. Their liver tissue was then examined by light and electron microscopy at different intervals for 14 months. Strong inhibitory effect of F6 on DAB-carcinogenesis was found.The changes produced in hepatocytes by F6 included the hypertrophy of nucleolus, disorganization and slight reduction of granular endoplasmic reticulum (GER), moderate hyperplasia of agranular endoplasmic reticulum (AER), swelling of some mitochondria and diminition of glycogen content /Figs. 1-2/.
SEM study on gastrulation; internal structure at the stage of ventral blastoporal groove in bufo arenarum
Authors: Herkovits Jorge 
Published: June 2020

SEM studies on amphibian gastrulation have shown the overall shape and arrangement of several cell types (e. g. bottle cells, mesodermal cells, ectodermal cells, etc. ) as well as the cellular activities in the blastocoel cavity during archenteron floor descent. The main purpose of the present communication is to show the internal structure of Bufo arenarum gastrula as viewed in sagittal dissection at the stage when the ventral blastoporal groove starts forming.Material and Methods: Bufo arenarum gastrula were fixed in 2, 5% glutaraldehyde in phosphate buffer for 2, 5 hrs. After removing the vitelline membrane the embryos were fractured and then dissected near the mid-sagittal plane. The specimens were dehydrated through an acetone series, dried according to the critical point technique, coated with evaporated gold-platinum and observed in a Jeol JSM-U3 scanning electron microscope operated at 5-15 kW.Observations: The internal structure of a Bufo arenarum gastrula at the ventral blastoporal groove stage is illustrated in Fig. 1. Blastocoel cavity (B), internal endodermal yolky cells (Y), prospective ectoderm (PE), archenteron (A), dorsal blastoporal lip (L), ventral blastoporal groove (V).
Formation and behavior of the nurse cell giant granules in the sea urchin ovary
Authors: Takashima Y. , Tominaga A. , Kume T. 
Published: June 2020

The nurse cells in the sea urchin ovary indicate a peak of their development at the beginning of the breeding season. They contain giant granules (A-, B- and C-types) and glycogen particles in their cytoplasm as nutrient materials, which are taken into the growing oocytes during oogenesis (Fig. 1) The nurse cells indicate remarkable seasonal changes. As oogenesis proceeds the giant granules are broken down and materials in them are taken into the oocytes. Mature eggs contain cortical granules and yolk particles as the storage for nutrient materials. Nutrient intake of the oocyte from the nurse cells have been reported by us. The present report deals with the formation of the nurse cell giant granules and their behavior observed by the TEM, SEM and ultracytochemistry.The ovaries of two Japanese sea urchin species, Hamicentrotus pulcherrimus and Anthocidalis crassispina, during and after the breeding season were fixed in glutaraldehyde and/or in osmium tetroxide and prepared for TEM (section and freeze-fracture replica) and SEM observations. Ultracytochemistry, mainly for mucopolysaccharide and the catalase activity demonstrated by 3, 3' -diaminobenzidine (DAB) method, was also performed.
Fine structure of compound eyes of cicindela tranquebarica herbst (coleoptera: cicindelidae)
Authors: Kuster Janice E. 
Published: June 2020

The fine structure of photopic eucone eyes of Cicindela tranquebarica adults was examined using cryofracture SEM, TEM, and freeze-etch techniques. A “subcorneal layer” can be distinguished between the corneal lens and crystalline cone. In surface view (Fig. 1) this layer consists of concave polygons (po). It has parabolic lamellae (lm) of endocuticle consisting of microfibrils (mf) having a chitin core with protein deposits along their lengths (Fig. 2). Two primary pigment cells (lp) are devoid of pigment granules, but are rich in rough endoplasmic reticulum (rer) and surround a crystalline thread (ct) (Fig. 3). Extensions of the crystalline thread form inter-retinular fibers (f) containing microtubules between retinula cells 1/2, 3/4, 5/6, and 7/1 (Figs. 4, 5).Distal to each retinula cell nucleus are two basal bodies (bb), one perpendicular to the other (Fig. 4). The proximal body extends two fibrillar feet which fuse to form a horizontally banded ciliary rootlet which extends the retinula length peripheral to the rhabdom.
Proteoglycan alterations in rheumatoid arthritis—a light and electron microscopy study
Authors: Mitchell Nelson S. 
Published: June 2020

We have previously studied the ultramorphology oh cells in rheumatoid arthritis using conventional staining techniques. We have recently reported a technique for the precipitation and fixation of proteoglycan using Toluidine Blue 0 or Safranin 0 which permits simultaneous localization of proteoglycan using either light or electron microscopy in sections cut from the same block. This paper reports a study of rheumatoid arthritic cartilage using this technique.Samples oh cartilage were removed from the femoral condyles of thirteen patients with classical rheumatoid arthritis who were having operations on the knee. Control samples were removed from the knees of eleven normal patients who were having surgery for recent trauma. In both Instances, the tissues were prepared with Toluidine Blue or Safranin 0 Introduced into the fixation process as will be described.When fixed and stained by conventional methods, articular cartilage has been traditionally reported to consist ofi chondrocytes lying in a matrix of collagen and proteoglycan though separated from this matrix by a pericellular clear space, “halo” or “lacuna” of varying dimensions. This pericellular space was thought to contain only small amounts of collagen.
Electron microscopy of the microangiopathy and immunohistochemistry of the inflammatory infiltrate in eosinophilia-myalgia syndrome
Authors: Smith Stephen A. 
Published: June 2020

The ingestion of L-tryptophan (LT) was linked with the eosinophilia-myalgia syndrome (EMS) in the fall of 1989. The pathology is a microangiopathy consisting of endothelial cell dysfunction and invasion of blood vessels by lymphocytes. Perimysial, fascial, and dermal perivascular lymphocytes and eosinophils are present. A contaminant in the manufacturing process of LT has been identified as the di-L-tryptophan aminal of acetaldehyde. This report describes the electron microscopic appearance of the microangiopathy and the phenotyping of the inflammatory infiltrate by immunohistochemistry.Muscle, fascia, and skin biopsies from 21 affected individuals were rapidly frozen for light microscopy, histochemistry, and immunohistochemistry. For electron microscopy tissues were preserved in 4% formaldehyde-1% glutaraldehyde with post-fixation in osmium tetroxide. Thin sections were stained with uranyl acetate and lead citrate and examined in a JEOL 100CX electron microscope. Eight anlisera were used for the immunohistochemistry to identify lymphocyte subsets and macrophages. The markers were CD-2 (pan T), CD-3 (pan T), CD-4 (T helper), CD-5 (T helper), CD-8 (T suppressor), CD-19 (B cell), CD- 22 (B cell), and CD-68 (macrophage). Three high power fields were examined from the dermis, fascia, and muscle from eight biopsies counting the immunoperoxidase labelled cells for each marker.
Novel methods for demonstrating osseointegration of hydroxylapatite-coated titanium hip prostheses
Authors: Frayssinet P. , Hanker J. , Hardy D. , Giammara B. 
Published: June 2020

Prostheses implanted in hard tissues cannot be processed for electron microscopic examination or microanalysis in the same way as those in other tissues. For these reasons, we have developed methods allowing light and electron microscopic studies as well as microanalysis of the interface between bone and a metal biomaterial coated by plasma-sprayed hydroxylapatite(HA) ceramic.An HA-coated titanium hip prosthesis (Corail, Landos, France), which had been implanted for two years, was removed after death (unrelated to the orthopaedic problem). After fixation it was dehydrated in solutions of increasing ethanol concentration prior to embedment in polymethylmethacrylate(PMMA). Transverse femur sections were obtained with a diamond saw and the sections then carefully ground to a thickness of 200 microns. Plastic-embedded sections were stained for calcium with a silver methenamine modification of the von Kossa method for calcium staining and coated by carbon. They have been examined by back-scatter SEM on an ISI-SS60 operated at 25 KV. EDAX has been done on cellular inclusions and extracellular bone matrix.
Microstructural comparison of synthetic bioceramics with natural bioceramics
Authors: Wen Shulin , Feng Jingwei , Krajewski A. , Ravaglioli A. 
Published: June 2020

Hydroxyapatite bioceramics has attracted many material scientists as it is the main constituent of the bone and the teeth in human body. The synthesis of the bioceramics has been performed for years. Nowadays, the synthetic work is not only focused on the hydroapatite but also on the fluorapatite and chlorapatite bioceramics since later materials have also biological compatibility with human tissues; and they may also be very promising for clinic purpose. However, in comparison of the synthetic bioceramics with natural one on microstructure, a great differences were observed according to our previous results. We have investigated these differences further in this work since they are very important to appraise the synthetic bioceramics for their clinic application.The synthetic hydroxyapatite and chlorapatite were prepared according to A. Krajewski and A. Ravaglioli and their recent work. The briquettes from different hydroxyapatite or chlorapatite powders were fired in a laboratory furnace at the temperature of 900-1300°C. The samples of human enamel selected for the comparison with synthetic bioceramics were from Chinese adult teeth.
Quantitative geometric scanning electron microscopy
Authors: Bastacky Jacob , Hayes Thomas , Yager Deborah , Lee Charles 
Published: June 2020

Quantitative SEM assessment of the geometry of biological specimens requires attention to 1) statistically valid sampling, 2) dimensional changes during fixation, dehydration, drying, and cutting, 3) artifacts produced by coating, 4) microscope raster and display system field distortion 5) magnification calibration 6) stage tilt calibration and hysteresis, and 7) counting protocols for selecting parts of the final images as data.This analysis is necessary, for example, in measuring the thickness of the liquid layer lining the alveoli in lung from cross-fractured frozen hydrated pulmonary alveoli.Adequate numbers of animals, with samples from each significant organ region must be studied. Sampling may be in a stratified random manner or by guided microdissection to preserve additional structural information.
Effect of monocrotaline pyrrole on cultured cell cytoskeletons: An ultrastructural study
Authors: Wood J.I. , Klomparens K.L. , Hoorn C.M. , Roth R.A. , Reindel J. 
Published: June 2020

The cytoskeleton (CS) is responsible for locomotion, intracellular motility and maintenance of cell structure. The system is composed of three major components: microfilaments, responsible for motility and cell structure, microtubules for organization and movement within the cell, and intermediate filaments, which may provide stability of intracellular contents.Monocrotaline (MCT) is a pyrrolizidine alkaloid plant toxin. When administered to rats, MCT is metabolized to monocrotaline pyrrole (MCTP) which induces lung injury and pulmonary hypertension. When administered to cultured pulmonary artery endothelial cells, MCTP causes progressive detachment, release of LDH, inhibition of cell proliferation, and distorted and enlarged nuclei. MCTP is a bifunctional alkylating agent that can crosslink DNA. We speculate that MCTP may also affect the cytoskeleton, resulting in inhibition of cell division.
Application of post-embedding immunogold technique in the diagnostic evaluation of fine-needle aspirates of neuroendocrine tumors
Authors: Diocee M. , Ravinsky E. , Quinonez G. 
Published: June 2020

The diagnostic feature of a neuroendocrine tumor by transmission electron microscopy (TEM) is the presence of neurosecretory granules (NSG). However, other electron dense inclusions like lipid droplets and primary lysosomes may mimic NSC. In this study, post-embedding immunogold (PEI) technique using chromogranin A antibody has been used to confirm the ultrastructural impression of neuroendocrine tumor. This technique is contrasted with immunohistochemical results.Material for this study was obtained from 5 transabdominal fine needle aspirates of multiple hepatic masses of unknown nature, processed for light and electron microscopic examinations and immunohistochemistry. Thin gold sections were cut (Reichart) with a Diatome diamond knife and mounted on 200 mesh nickel grids. A nickel grid with section side down was placed on drops of 11% aqueous sodium metaperiodate for 30 minutes, and was then washed with distilled water. Grids were incubated in 1% albumin for 15 minutes and transferred directly to chromogranin A and incubated for 60 minutes at room temperature.
Sertoli-germ interactions in iron-administered rats: An ultrastructural study
Authors: Bains H.K. , Kanwar K.C. , Bawa S.R. 
Published: June 2020

The antitesticular effect of many heavy metal salts including iron has been reported to cause gonadal atrophy in rats I However, altered ultrastructural events of Sertoli-germ cell interactions following exogenous administration of iron has not been clarified. Present study was undertaken to identify the testicular organelles most affected in ferrous gluconate injected rats.Sexually mature male albino rats weighing 175-180 grams were put on ferrous gluconate for 2 months by intraperitoneal injections at a dose rate of 20 mg/kg body weight/day. Slices of testes were fixed at room temperature in 3% glutaraldehyde in 0.1M phosphate buffer pH 7.4 for 2 hours, postfixed in 1% osmium tetraoxide in 0.1M phosphate buffer. After thorough rinsing of the fixed material with phosphate buffer pH 7.4 samples were dehydrated through graded acetone prior to embedding in Epon-Araldite. Subsequently ultrathin sections were stained with Uranyl acetate and Lead citrate (Reynold's) and examined under Jeol 1200EX electron microscope.
Nano-area analysis by an energy-dispersive x-ray spectrometer mounted on a field-emission transmission electron microscope
Authors: Hashimoto T. , Sato Y. , Ueki Y. , Kamino T. , Isakozawa S. , Ikematsu Y. , Uemori R. , Morikawa H. 
Published: June 2020

Hitachi HF-2000 is an analytical electron microscope equipped with a cold field emission electron source which is operable at 200kV. The cold field emission source has an excellent coherency of the beam and an inherent source brightness of about 1,000 times greater than that of the conventional heated sources such as a tungsten hairpin type filament or a LaBs emitter. The HF-2000 is, therefore, advantageous in the following points:1)In the TEM imaging, the illumination beam angle is about 1/10 of conventional microscopes. The information limit can be extended to a higher spacial frequency.2)In a focused fine probe of about 1 nm in diameter, which is typically used for elemental microanalysis, a high probe current of about 100 times greater than that available with conventional TEMs, is available.In addition, it is also possible with the HF-2000 to check the analysis area in high resolution TEM image with sufficient image brightness and contrast during the x-ray work. This capability assures high positional accuracy for point analysis.