bluuebunny/crossref_metadata_2025_split huggingface dataset:
Observation of hydrated muscle by the use of side-entry environmental cell
Authors: Suda Hitoshi , Ishikawa Akira , Fukami Akira 
Published: June 2020

In our laboratory, the wet cell microscopy has been developed to observe hydrated materials by using film sealed environmental cell (hydration chamber; abbreviated as EC). We have also reported results of dynamic observations of hydrated biological or non-biological materials such as the biological reaction process of muscle fiber, the chemical reaction process of photographic silver halide crystals and so on. In this study, to prevent completely the evaporation of solvent in the process of setting of sample and the observation, the spacer composing the EC was improved to have the injection function of two solutions (as seen in figure 1) in addition to the water vapour saturated gas circulation system used previously. Such a new injection method may be very useful for the drying sensitive specimen as well as for the action of two solutions.As far as one observes the specimen with electron microscope, the radiation damage of specimen may be inevitable. To reduce such a damage, some devices are especially necessary in the EC. Before observing “living” biological specimen, however, one must know the critical dosage at which the biological function is lost. In order to estimate the critical value, we performed one experiment by utilizing the function of muscle contraction. Since we can easily judge whether or not “the muscle is living” by observing the contraction phenomen a which cause very dramatic structure change, the muscle fiber is thought to be a very suitable sample for our aim.
Desmosome-like structure between lymphocytes of developing thymus of foetal lamb
Authors: Alsalami Mohammed T. 
Published: June 2020

The foetal thymuses of sheep from 40 days to full term gestation were studied. The earliest thymuses that were studied were obtained from foetuses of 40 days gestation. At this stage of development the thymic tissue was formed of cords of condensed epithelial cells. Lymphopoiesis occurred in these thymuses between the thymus of 40 day old foetus and those of 42 days was striking and indicated that the onset of lymphopoiesis in the foetal sheep occurred abruptly. From 42 days onwards there was a rapid increase in the size of the thymus and in the extent of the lymphopoiesis (Fig. 1). By 45 days gestation the distribution of the lymph cells in the thymus had begun to define the cortex and medulla, and the organ was plainly lymphoid.Apart from lymphoid and epithelial cells, macrophages, erythroblasts and granulocytic myelocytes were sometimes found in the thymus (Fig. 2). Many of die lymphocytes within the cortex were closely attached to one another, the point of attachment resembling tight junctional complexes that normally found between epithelial cells (Fig. 3 and 4).
“Anti-rigor” cross bridges may reflect altered state of actin
Authors: Trombitás Károly , Pollack Gerald H. 
Published: June 2020

We reported earlier that in insect flight muscle, myosin heads could form either rigor bridges or “anti-rigor” bridges, with reversed angle. When rigor develops at constant fiber length, the bridge angle is typically 45°—the rigor bridge. When rigor develops isotonically, so that the specimen can shorten, regularly arranged anti-rigor bridges are also observed.To investigate anti-rigor bridges further, bumblebee-ilight muscle fibers were prepared as described previously. Fresh fiber samples were stretched to 5-15% beyond their natural length, and then chemically skinned by a two-hour soak in a relaxing solution containing 0.5% Triton X-100. The stretched muscles were then alternately transferred and kept for 20 minutes in relaxing and rigor solutions until some of the fibers broke as a result of the developing rigor tension. Samples were then fixed in rigor, and the broken fibers were separated from the intact fibers.Micrographs of the intact fibers revealed the conventional rigor-bridge angles (Figure. 1). “Chevrons” formed by bridge pairs pointed away from the Z-line in a regular manner.
An Electron Microscopic study of the liver in certain marine teleosts
Authors: Ooi V.E.C. , Ooi Linda S.M. , Ma Shuyi 
Published: June 2020

The hepatic parenchyma of five marine teleosts (belonging to five families in the Teleostei) was investiga ted during the summer months by means of light and transmission electron microscopy. The architectural organization of the livers of these teleosts displays remarkable differences with regard to the interrelationship with the pancreatic tissue. In Lates calcarifer and Lutjanus bohar, prominent pancreatic tissue is found in the liver, following the course of portal vein and hepatic artery and surrounding the branches of these vessels. The pancreatic tissue appears less abundant in Mylio macrocephalus than in the preceding species. In Siganus javus and Gymnothorax schismatorhynchus, there are no dispersed intrahepatic pancreas. The liver lobules are defined by the presence of connective tissue strands in Lates and Siganus, but in the other three species there was no precise lobulation of the hepatic tissue.The microstructure of the livers in these teleosts is basically the same in all cases, although there are considerable variations inultrastructure of their parenchymal cells. The plates of hepatocytes which are usually two or more cells thick is in terrupted by sinusoids lined with fenestrated endothelial cells and Kupffer cells (Figs. 1, 2).
Crustacean olfaction: The daphnid aesthetascs lead to a changed structural concept
Authors: Elofsson Rolf , Walleén Rita 
Published: June 2020

Aesthetascs situated on the first antennae of crustaceans are easily recognized and distinguished from other sensilla by their hose-like appearance and thin cuticle. Their internal structure is known from decapod, mysid and isopod, i.e. malacostracan crustaceans. The aesthetasc is characterized in these animals by a large number of sensory neurons below each single aesthetasc. The neurons give rise to - from their dendrites - two cilia. The cilia protrude into the external hose-like portion of the aesthetasc splitting up into many branches. It is generally agreed that the aesthetascs are the structural base for crustacean olfaction and experiments to verify this have been performed mostly on malacostracan species.The water-flea, Daphnia, is a non-malacostracan species. It has greatly reduced first antennae and externally only nine pairs of aesthetascs remain (Figs 1, 2). The outer morphology agrees with that of malacostracan species. The internal morphology does not. Each of these aesthetascs has only four sensory cells situated deep inside the animal. The sensory cells have only one cilium (Fig. 3) extending unbranched into the external portion of the aesthetasc (Fig. 4).
Ultrastructural and morphometric examination of renomedullary interstitial cells and their lipid granules treated with a prostaglandin synthetase inhibitor
Authors: Seçkin İsmail , Hekimoğlu Nezih , Taşyürekli Mustafa , Yılmazer Selma , Arda Oktay , Şatıroğlu Güngör 
Published: June 2020

Experiments points out that renomedullary interstitial cells (RIC) are responsible for antihypertensive function of kidney medulla, but functional roles of lipid granules (LG) of the cell in prostaglandin and renomedullary hormone synthesis are still being discussed. We searched, the relationship in between LG and PGE2 synthesis capacity of RIC in rats induced with a prostaglandin synthetase inhibitor (indomethacin). Three months old 6 Wis-tar rats used in control and experiment groups. Daily doses of 5 mg/kg indomethacin introduced orally to rats in experiment group for 12 days. PGE2 levels were determined in blood samples obtained from left renal vein (Tab.1). Electron microscopic specimens prepared from inner medulla of right kidneys. We caunted LG in 100 RIC of each rat (Tab.1). Frequency of LG groups in control and experiment groups are shown in (Tab.2).Observations in experiment group; increased cytoplasmic matrix density, mitochondrial swelling, both enlargement of GER and perinuclear cisterna, decreased number of vesicles and nuclei rich in heterochromatin (Fig:2,3,4), points out a declined synthesis and secretion activity of RIC.
Substructural tubular network in the matrix of induced peroxisomes of rat hepatocyte
Authors: Makita Takashi , Hirose Haruko 
Published: June 2020

In the course of cytochemical study of the localization of Ca+2-ATPase and Mg+2-ATPase on the peroxisomal limiting membrane, and also X-ray microanalysis of accumulated metalic elements in the matrix of peroxisomes, we were awear of the fact that the matrix of peroxisome contained a number of tubular or circular membranous structure. Those structure in matrix were not always clear in matured peroxisomes and likely to be overlooked but rather evident in newly formed peroxisomes which had lighter matrix. This report is to confirm the tubular substructure in the matrix of peroxisomes those which were proliferated in hepatocytes after administration of clofibrate to rats.Male Wister rats(250-280g) were fed with diet containing 0.5% clofibrate for 3 weeks. Each animal was perfused with 2.5% glutaraldehyde buffered with 0.1M sodium-cacodylate-HCl at pH7.4. Ultrathin sections were observed with H-700(Hitachi) and EM-002A(ISI Akashi).
Ultrastructure of periplasmic bodies in gram-negative bacteria
Authors: Nianming Xie , Shaoqing Ding , Luping Wang , Zenglin Yuan , Guolai Zhan , Shuhui Lang 
Published: June 2020

Perhaps the data about periplasmic enzymes are obtained through biochemical methods but lack of morphological description. We have proved the existence of periplasmic bodies by electron microscope and described their ultrastructures. We hope this report may draw the attention of biochemists and mrophologists to collaborate on researches in periplasmic enzymes or periplasmic bodies with each other.One or more independent bodies may be seen in the periplasmic space between outer and inner membranes of Gram-negative bacteria, which we called periplasmic bodies. The periplasmic bodies have been found in seven species of bacteria at least, including the Pseudomonas aeroginosa. Shigella flexneri, Echerichia coli. Yersinia pestis, Campylobacter jejuni, Proteus mirabilis, Clostridium tetani. Vibrio cholerae and Brucella canis.
Effect of UV-B radiation on the C4 plant Zea mays L.
Authors: Santos Isabel , Almeida J. M. , Salema R. 
Published: June 2020

The known reduction of stratospheric ozone by some pollutants increased the amount of ultra-violetligth reaching the earth's surface raising concerns about its effects on life, since UV-B (280-320 nm) is absorbed by proteins and affects important plant processes such as photosynthesis, transpiration, leaf expansion, dark respiration and biomass. It was thought of interest to subject a C4 plant to this type of injury to see if both types of cells and chloroplasts in their leaves reacted similarly to the treatment.Zea mays var. LG12 were germinated in vermiculite and plants developed under a 14 hlight photoperiod till they had three expanded leaves. From this stage one set was used as control and other received UV-B provided by a Philips TL 40/12 lamp in addition to white light giving an irradiance of 900 μE m-2s -1 .
Ultrastructural details of leaf papilla development in the moss Andreaeobryum macrosporum
Authors: Crandall-Stotler Barbara J. , Bozzola John J. 
Published: June 2020

Projecting papillae ornament the abaxial leaf surfaces of many mosses, including those of the primitive, ectohydric taxon Andreaeobryum macrosporum Steere & B. Murr.. Such papillae presumably create a network of capillary spaces on the leaf surface proper, through which water can be effectively transported, while providing a water-repellent surface for CO2 uptake at the papillar tips. Although thesuperficial characteristics of such papillae have been recorded frequently with SEM,nothing is knownof their development or ultrastructural organization.Plants collected on limestone outcrops in the Brooks Range, Alaska in June, 1989, were transferred, intact, to culture dishes of vermiculite, moistened with Hatcher's nutrient solution, and maintainedinan environmental chamber with a 1160 lux, 16 h day: 8 h night light regime at 5 C constant temperature. Shoot apices, 1-2 mm long, were excised from both freshly collected and cultured specimens intoa 1% Triton X solution, 1 h prior to fixation in 2% glutaraldehyde plus 2 % paraformaldehyde in 0.1 MNa-cacodylate buffer, pH 7.2, for 4 h at room temperature.
The ultrastructure of the double membrane-bound bodies and endoplasmic reticulum in serial sections of wheat spot mosaic-affected wheat plants
Authors: Chen M. H. , Hiruki C. 
Published: June 2020

Wheat spot mosaic disease was first discovered in southern Alberta, Canada, in 1956. A hitherto unidentified disease-causing agent, transmitted by the eriophyid mite, caused chlorosis, stunting and finally severe necrosis resulting in the death of the affected plants. Double membrane-bound bodies (DMBB), 0.1-0.2 μm in diameter were found to be associated with the disease.Young tissues of leaf and root from 4-wk-old infected wheat plants were fixed, dehydrated, and embedded in Spurr’s resin. Serial sections were collected on slot copper grids and stained. The thin sections were then examined with a Hitachi H-7000 TEM at 75 kV. The membrane structure of the DMBBs was studied by numbering them individually and tracing along the sections to see any physical connection with endoplasmic reticulum (ER) membranes. For high resolution scanning EM, a modification of Tanaka’s method was used. The specimens were examined with a Hitachi Model S-570 SEM in its high resolution mode at 20 kV.
Ruthenium tetroxide vapor staining of dry specimens for Scanning Electron Microscopy
Authors: Takahashi Gen 
Published: June 2020

For non-coating scanning electron microscope study of dry specimens, exposure of specimens to osmium tetroxide vaper was attempted. Ruthenium tetroxide(RuO4) is a volatile far more reactive oxidant than osmium tetroxide. In the present study treatment with RuO4 vaper has been found to be successful in fixing and conductively staining dry or semidry biological or non-biological specimens without any special device.The method of RuO4 vaper stainingDry or semidry specimens of appropriate size are placed in a glass container with a small bottle containing RuO4 solution or crystal powder. The glass container is tightly stoppered and the specimens are exposed to the vaper of RuO4 for half or several hours. These procedures are carried out in a draft at room temperature. The specimen surface is progressively darkened,indicating the binding of reduced ruthenium(RuO2) to the specimen by the oxidation-reduction reaction in vaper phase. The reduced ruthenium render the specimen conductive and stable under the intense electron beam during SEM observation without metal coating.
Tracing the use of freshwater naiad shells as prehistoric implements through scanning electron microscopy and x-ray microanalysis
Authors: Kristina Hirst K. , Thompson Robert G. , Walters Katherine S. 
Published: June 2020

Many freshwater naiad shells recovered from prehistoric Iowa archaeological sites have edges exhibiting patterns of use-wear. The ethnographic and ethnohistoric records contain accounts of the use of these shells in the removal of kernels from corn cobs. Recently, archaeologists have begun tracing use of stone implements through analysis of microscopic wear patterns and deposition of material such as opal phytoliths. Opal phytoliths are small silica bodies which plants deposit within and between some cells. Corn is among the plants which produce opal phytoliths in abundance. Experimentally created naiad shell implements were used to remove kernels from corn cobs. The deposits left on the edges of these implements were compared to those of prehistoric naiad shells thought to be utilized. Scanning electron microscopy (SEM) and x-ray microanalysis were utilized.The prehistoric and experimentally created edges were prepared for examination by cleaning and coating with carbon. Examination of the tools was performed with a Hitachi S-570 electron microscope equipped with a Kevex 8000 x-ray microanalyzer.
Microwave fixation of large tissue
Authors: Sakai Toshio , Uchizono Koji 
Published: June 2020

Chemical fixation of large biological tissues in electron microscopy has a disadvantage that fixative doesn’t penetrate well into the deeper part of the tissue. My experience suggests that the poor penetration by chemical fixation can be improved by microwave fixation. Temperature raise caused by microwave irradiation is regulated by the cold bath on the floor of the oven. This paper shows that microwave fixation is readily practicable together with conventional fixation. Well-fixed section with an area as large as 1×5mm is observable and the details of morphological structures are preserved quite well in it.A commercial microwave oven (National Microwave Oven Model NEM-335,2.45GHz 500/180W) was used for the microwave fixation. Irradiation period was controlled by Omuron H5cN-AN. Young mouse kidney and brain were used. The tissue in a glass vial placed in the cold bath was immersed in the mixture of 2% paraformaldehyde and 0.5% glutaraldehyde in phosphate buffer (pH7.4),followed by microwave irradiation for 10 sec. twice.
Electron spectroscopic imaging of isolated myocardial cells prepared by slam-freeze molecular distillation processing
Authors: Rufner Robyn , Stearns Rebecca C. , Hastings Cindy L. , Borzak Steven , Godleski John J. 
Published: June 2020

Isolated adult rat ventricular myocytes serve as a well-defined model to study subcellular events associated with cardiac ischemia. Optimal ultrastructural preservation of in vivo and cultured myocardial cells has been approached by cryo-preservation techniques involving rapid freezing and subsequent freeze substitution or freeze-dried cryosections. Alterations in biochemical structure and composition inherent with chemical fixation procedures can be alleviated by molecular distillation drying of cryo-fixed specimens. In this morphological study, the effects of metal-mirror cryofixation and molecular distillation processing of myocardial cells was evaluated using electron spectroscopic imaging.Myocardial cells were isolated from the ventricles of adult female Sprague-Dawley rats by enzymatic digestion. Briefly, perfused ventricles were minced and incubated with calcium-free Krebs-Henseleit buffer containing 0.05% collagenase and 0.03% hyaluroxidase with 0.002% deoxyribonuclease II and 0.002% trypsin and 1 mM Ca for 10-20 min at 37° with continuous oxygenation and shaking. The tissue was transferred to KH-enzyme buffer plus 2% bovine serum albumin, filtered through Nitex mesh, sedimented by centrifugation (150xg) and then resuspended in 1 mM Ca KH buffer with 2% bovine serum albumin. The yield of viable cells was greater than 70%.
A film recording and image processing system for confocal microscopy
Authors: Ackerman Larry D. , Jansen W. T. 
Published: June 2020

Scanning confocal microscopy has developed into a very useful technique for many scientific investigations. However, commercial development has been so rapid that some recent advances in computer graphics and imaging have not been incorporated into the commercial systems. One particular concern was high quality hard copy with alpha-numeric and graphic overlays. A subsystem was developed to provide this output for the BioRad MRC-500/600 confocal imaging system.A digital film recorder, an Agfa Matrix Procolor was chosen as the principal element of hardware. This compact unit can record an image at a resolution of 4096 horizontal by 3072 vertical pixels at a cost equivalent to popular analog video film recorders. The interface is a standard IEEE 488 GPIB board. It is compatible with various film emulsions such as Kodak Ecktachrome 100 as well as many of the major graphics arts and image processing programs. The second element of hardware in this system is an ATVista 4M image processing board.
Immunoelectron microscopic study of secretory granules containing atrial natriuretic peptide in human ventricular cardiomyocytes
Authors: Lee Ching-Ping , Lee Ying-Shiung 
Published: June 2020

With the morphological description of the secretory granules characteristically occurring in the atrial muscle cells a broad, deep and rapid series of studies has provided unequivocal evidence for a potent natriuretic and vasorelaxant substance, namely atrial natriuretic peptide (ANP), arising in the atrial granules. It now appears that these granules are not specific for the atrium but are only most frequent in adult atrial cells, since they may occur to lesser extent in the extra atrial tissues of some species. Thus, the purpose of the present report was to characterize the ANP-containing granules arising in the ventricular muscle cells in patients with dilated cardiomyopathy and chronic heart failure by means of immunoelectron microscopy.Electron microscopic immunocytochemical study of left ventricular myocardium obtained from endomyocardial biopsy was carried out in a total of 50 consecutive patients with various etiologies of heart disease. Biopsied specimens were fixed with 2% glutaraldehyde buffered with 0.1 M cacodylate (pH 7.4) at 4°C for 60 min. and postfixed with 1% osmium tetroxide in the same buffer solution.
Immunocytochemical localization of calcitonin gene-related peptide in the rat spinal lamina X
Authors: Nasu Fumio , Inomata Kenichirou 
Published: June 2020

The region surrounding the central canal, lamina X, of the spinal cord is thought to receive in formation concerning the noxious stimulation of the periphery (Nahin RL et al. 1983). The present study is to perform the localization of calcitonin gene-related peptide in region surrounding the central canal of rat spinal cord.Normal adult Wistar rats were anesthetized with sodium pentobarbital and perfused through the left ventricle with a mixture of 0.25% glutaraldehyde, 8% paraformaldehyde and 1% picric acid in 0.1M phosphate buffer, pH 7.4 for several minutes, 0-4°C. After perfusion the spinal cord were removed and immersed in same fixative for 60 min at 0-4°C. The fixed tissues were rinsed in cold 0.1 M phosphate buffer (pH 7.4) containing 8% sucrose and 1% sodium borohydride for 30 min. For light microscopic study, the paraffin sections and Microslicer-sections were immunostained by the peroxidase-antiperoxidase method (Sternberger LA 1979). For electron microscopical study, the ultrath in frozen sections method (Tokuyasu KT 1986)were used
Immunoelectron microscopic localization of 22 KDA protein antigen in the surface layer of Mycobacterium bovis BCG strains
Authors: Lounatmaa K. , Brander E. 
Published: June 2020

Recently a paracrystalline surface layer (the S-layer) was observed as the outermost layer of the cell wall of Mycobacterium bovis strains. This crystalline protein layer was found in the Glaxo BCG strains, one Russian strain and three Finnish strains isolated from the patients with BCG complications.In the thin sectioned and freeze-etched cells the periodic structure was seen in the outermost layer of the cel wall. The sectioned cells (Fig. 1) were bound together by the layer, which was electron dense (S-layer). In the metal shadowed cells, however, the periodicity was clearly seen (Fig. 2). The linear (oblique) arrangement of the subunits in the S-layer was observed and the distance between the rows of the subunits was measured to be about 5.5 nm.Cryosections, monoclonal antibody M. bovis 4C3/17 antibody (AGEN Bicmedical Limited, Queensland, Australia) and both 5 nm and 10 nm Auroprobe protein A (Janssen, Belgium) were used to study, whether the 22kDa protein (MPB70) could form the S-layer of M. bovis strains studied.