bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ultrastructural characterization of basophils and mast cells derived from CD34+ human bone marrow progenitor cells
Authors: Goff J.P. , Kirshenbaum A. S. , Albert J. P. , Metcalfe D. D. 
Published: June 2020

In the mouse, mast cell progenitor cells (Thyl +) have been shown to originate in the bone marrow. In humans, it has been suggested that mast cell progenitors also exist in the bone marrow, are derived from a common stem cell, and mature under cytokine influence in the tissue. Progenitor cells or CD34+ cells comprise approximately 1% of bone marrow mononuclear cells.Previously we have shown that a heterogenous population of human bone marrow cells cultured over agarose surfaces in the presence of rhIL-3 gives rise to basophils and small numbers of mast cells. Cells were identified as basophils based on characteristic morphology, metachromatic staining with Wright-Giemsa and acid toluidine blue, surface IgE as determined by fluorescence and the presence of histamine by o-Phthaldialdehyde condensation. These cells did not stain for the mast cell specific neutral protease, tryptase. Cells identified as mast cells had IgE receptors, contained histamine and were chloroacetate esterase and human mast cell tryptase positive.
Ultrastructural morphology of neurosecretory neurons in the barnacle Balanus amphitrite
Authors: Tagliafierro Grazia , Crosa Cristiana , Canepa Marco , Zanin Tiziano 
Published: June 2020

Barnacles are very specialized Crustacea, with strongly reduced head and abdomen. Their nervous system is rather simple: the brain or supra-oesophageal ganglion (SG) is a small bilobed structure and the toracic ganglia are fused into a single ventral mass, the suboesophageal ganglion (VG). Neurosecretion was shown in barnacle nervous system by histochemical methods and numerous putative hormonal substances were extracted and tested. Recently six different types of dense-core granules were visualized in the median ocellar nerve of Balanus hameri and serotonin and FMRF-amide like substances were immunocytochemically detected in the nervous system of Balanus amphitrite. The aim of the present work is to localize and characterize at ultrastructural level, neurosecretory neuron cell bodies in the VG of Balanus amphitrite.Specimens of Balanus amphitrite were collected in the port of Genova. The central nervous system were Karnovsky fixed, osmium postfixed, ethanol dehydrated and Durcupan ACM embedded. Ultrathin sections were stained with uranyl acetate and lead citrate. Ultrastructural observations were made on a Philips M 202 and Zeiss 109 T electron microscopy.
Immunolocalization of individual filament-forming proteins in the cytoskeleton of Tetrahymena
Authors: Yi Hong , Williams Norman E. , Dress Virginia M. , Moore Kenneth C. 
Published: June 2020

Four polypeptides (tetrins I-IV) have been isolated from the ciliated protozoan Tetrahvmena pyriformis. These polypeptides assemble in vitro into 3-4 nm filaments identical with those present in abundance in a cytoskeletal framework associated with the feeding organelle system (oral apparatus) of this cell type. The polypeptides ranging in molecular weights from 79-89 kDa are not similar to each other in either biochemical or immunological properties. In vivo, the filaments are organized into higher order structures described as cages, cables, and networks. The specific hypothesis arises that the alternate packing arrangements may correlate with different distributions of the individual tetrin polypeptides. We report the production of monoclonal antibodies for each tetrin polypeptide, and the determination of the location of each within the cell using confocal microscopy and immunogold-silver enhancement procedures in conjunction with transmission electron microscopy (TEM).Cell samples for confocal microscopy were labelled according to conventional immunofluorescent procedures and examined with a Bio-Rad MRC-600 laser scanning confocal microscope.
Scanning Electron Microscopy of antennal sensilla of the Japanese tusser, Antheraea vamamai
Authors: Jian Hong , Cui Hu , Congyin Ye , Qikang Gao 
Published: June 2020

Antennal surface structure of the Japanese tusser, Antheraea yamamai was observed by scanning electron microscope. The antennae of male and female were bipectinate with scape, pedicel and 33--37 flagellar segments. There were two pairs of equal long branch on eacli flagellar segment of male (Fig.1), but a pair of longer and a pair of shorter on female's (Fig.2).Seven types of sensillum, namely sensillum trichodeum, sensillum cheaticum, sensillum coeloconicum, sensillum campaniformlum, sensillum styloconicum, Bohm's bristle and sensillum squamiformium wer found on the antenna both of male and female. The sensillum trichodeum could be subdivided into long and short according to the shape and surface substructure. The long sensillum trichodeum had a diameter of 4.8μm at its base. It was reratively stright and slightly curved at the tip (Fig.3). The short sensillum trichodeum was 2.5--3.6 μm in diameter at the base. It was shorter, strongly bend down near its base and run parallel with the surface of the antenna (Fig.4). The surface of long and short sensilla trichodea were covered with annular ridges (Fig.5).
Ultrastructure of microfilarial sheath and its comparison with egg shell
Authors: Howe Lye , Chun Josephine , Zaman Viqar 
Published: June 2020

In this study the ultrastructure of the uterus of Brugia malayi and its contents were studied especially to reveal the relationship between the sheath of the microfilaria and the egg shell, as it is claimed that the egg shell ultimately forms the microfilairal sheath (Rogers et al, 1976).The cross section of the worm revealed a distinct cuticle, musculature, a single patent fut and paired uteri. The uterine contents were filled with eggs at various stages of development. Inside each egg were embryonic cells which corresponded to the so-called “nuclei” of microfilaria which are seen in the light microscope. The egg shell was discernable as a membrane with minute electron-dense projections on its surface. At higher magnification the egg shell was seen to consist of two structures - a homogenous basement membrane and electron dense projections which rested on it. These projections were found all around the egg shell and consisted of a broad base and a pointed anterior end.
Impact of social environment on the fat body development of worker ants
Authors: Rosell Rosemarie , Wheeler Diana E. 
Published: June 2020

In ants, colonies are composed of one or a few queens and many female, but usually sterile, workers. The reproductive capability of workers is inhibited by the queen. In the ant genus,Camponotus, workers can develop the capacity to lay eggs in the absence of the queen. Large workers, termed soldiers, show the greatest tendency to deposit yolk and lay eggs. The insect fat body is the site of synthesis of proteins used in reproduction, most notably vitellogenin. In this study, we compare the development of fat body in soldiers that have been maintained in the presence of the queen (Q+) with those that have been removed from her inhibitory influence (Q-).Just before the adult molt, pupae were removed fromC. festinatusparent colonies maintained in the laboratory. After emergence, individuals were divided into two groups. Q- individuals were maintained in petri dishes in groups of 25-30 in the absence of the queen. Q+ workers were marked and immediately returned to the parent colony.
The distribution and density of ciliary tufts on the siphons of Anodonta cygnea (Mollusca: Bivalvia)
Authors: Wu Wen-lung 
Published: June 2020

The mantle of bivalves has come entirely to enclose the laterally compressed body and the mantle margin has assumed a variety of functions, one of the pricipal ones being sensory. Ciliary tufts, which are probably sensory, have been reported from the mantle and siphons of several bivalves1∽4. Certain regions of the mantle margin are likely to be more or less, sensitive to certain stimuli than others. The inhalant siphon is likely to be particularly sensitive to both chemical and mechanical stimuli, whereas the exhalant siphon will be less sensitive to both. The distribution and density of putative sensory receptors on the in-and ex-halant siphon is compared in this paper.The excised siphons were fixed in glutaraldehyde and osmium tetroxide, the whole procedure of SEM study is recorded in Wu's thesis.Type II cilia cover the tips of tentacles, 6.13um. Type IV and type V cilia are found on the surface of tentacles. Type IV cilia are occasionally present at the tips of tentacles, 8 um long. They are the commonest type on the surface of tentacles. Type VI cilia occor in the internal surface of the inhalant siphon, but are not found on the surface of tentacles, 6.7-10um long.
Scanning Electron Microscopic study of bats hair as an aid of species identification
Authors: El Gohary M. , Banerjee R.K. , Nader I.A. 
Published: June 2020

Cuticular scales patterns of hair shafts have been studied in order to show variations associated with mammalian species bearing hair. Results of microscopical studies of mid-dorsal hair shafts of certain Philippine bats showed that the type of pigmentation and the cuticular scales did not vary within the genera but did within the families. It is clearly demonstrated that the mammals showed variant patterns of cuticle structure of hair shafts by SEM and could be used for identifying different mammals.Mid-dorsal hair shafts of 15 species of Saudi Arabian bats (O.Chiroptera) were ultrasonically cleaned, dehydrated, coated with gold/palladium and photographed by JSM-35. The hair cuticle of 15 species of different genera and families of bats were investigated (Rhinopoma microphyllum, Rousettus aegyptiacus, Taphozous perforatus, Tagphozous
A TEM study on the uptake of AMI 25 by sinusoidal liver cells
Authors: Wisse E. , Doucet D. , Van Bossuyt H. 
Published: June 2020

Earlier studies have indicated that the liver plays a major role in the clearance of Ami 25 colloidal particles, consisting of dextran-stabilized superparamagnetic ferric oxyhydroxide citrate, used for increasing the contrast during NMR imaging of the liver. The uptake of these particles by different cell types in the rat liver was studied, at time intervals ranging from 3 minutes to 1 month.Two different dose levels were used, i.e. a single, low dose of 1,1 mg Fe/kg, comparable to the dose given to patients, and a single, tenfold dose of 11,3 mg Fe/kg. Controls received saline injections. I.v. injections were given to young adult male Wistar rats. After perfusion fixation of the liver with isotonic, buffered, 1.5% glutaraldehyde, at 10 - 12 cm H2O pressure during 7 min at 20 °C and a flow rate of 7ml/min, tissue blocks were postfixed in 1% osmium, dehydrated in ethanol, and embedded in Epon. Ultrathin sections were observed in the transmission electron microscope. In addition, Fe determinations were performed on total liver and on isolated sinusoidal cells.
Gold labeling of teichoic acid on adjacent surfaces of staphylococcus aureus
Authors: Hukee Margaret 
Published: June 2020

Gold labeling of two antigens (double labeling) is often done on two section surfaces separated by section thickness. Whether labeling is done on both sides of the same section or on two parallel surfaces separated by section thickness (PSSST), comparable results are dependent on an equal number of epitopes being exposed at each surface. We propose a method to study protein labeling within the same field of proteins, by examining two directly adjacent surfaces that were split during sectioning. The number of labeling sites on adjacent surfaces (AS) were compared to sites on PSSST surfaces in individual bacteria.Since each bacteria needed to be recognizable in all three section surfaces, one-hole grids were used for labeling. One-hole grids require a supporting membrane and excessive handling during labeling often ruptures the membrane. To minimize handling, a labeling chamber was designed that is inexpensive, disposable, minimizes contamination, and uses a minimal amount of solution.
Transmission Electron Microscopy of microorganism fine structure in dry state
Authors: Gerasimov V. , Volkov V. 
Published: June 2020

Routine methods for preparing biological specimens for electron microscopy are based on the usage of water solutions of fixatives. The Investigation of microorganisms in anabiosis shows that this results in rehydration of specimens and disturbance of the initial structure. In the paper it is proposed to use the waterless fixatives or the fixatives containing little water in order to analyze the structure of lyophilized microorganisms.Bacteria and yeasts in dry anabiosis were fixed in dehydrated OsO4 vapor. or in 1-2 % OsO4 solution on the basis of 97-95 % water acetone at room temperature for 24-72 h. After fixation, dehydrated microorganisms were placed on the formvar film by suspending cells in 1-4 % formvar solution on the basis of dichlorethan followed by suspension lyophilization on a glass up to film formation.
TEM processing procedure for a bacillus organism grown on solid media
Authors: Payne Jane , Coudron Philip 
Published: June 2020

This transmission electron microscopy (TEM) procedure was designed to examine a gram positive spore-forming bacillus in colony on various solid agar media with minimal artifact. Cellular morphology and organization of colonies embedded in Poly/Bed 812 resin (P/B) were studied. It is a modification of procedures used for undecalcified rat bone and Stomatococcus mucilaginosus.Cultures were fixed and processed at room temperature (RT) under a fume hood. Solutions were added with a Pasteur pipet and removed by gentle vacuum aspiration. Other equipment used is shown in Figure 3. Cultures were fixed for 17-18 h in 10-20 ml of RT 2% phosphate buffered glutaraldehyde (422 mosm/KgH2O) within 5 m after removal from the incubator. After 3 (30 m) changes in 0.15 M phosphate buffer (PB = 209-213 mosm/KgH2O, pH 7.39-7.41), colony cut-outs (CCO) were made with a scalpel.
Ultrastructure of E. coli: An in vitro study of cells cultured in the presence of four gastrointestinal (GI) hormones
Authors: Henz Leo J. , Johnson Frank E. 
Published: June 2020

Hormones are found in exocrine secretions entering the gut. They alter the morphology of many eukaryotic cells; whether they affect the morphology of enteric flora is unknown. In this study, we examined the ultrastructure of E. coli, a common bacterium in the mammalian gut, for morphological changes resulting from exposure to GI hormones.E. coli (#11775 from American Type Culture Collection) were grown in protease-free trypticase soy broth (TSB) at 37°C for 18 hr to a concentration of 2 x 107 cells/ml. Pure synthetic hormones were used: sulfated C-terminal cholecystokinin octapeptide (CCK), pentagastrin (PG), cyclic somatostatin tetradecapeptide (SS), or the porcine form of secretin (SEC). These were individually added to. bacterial cultures in TSB to make 1 x 107 organisms/ml and 0.0, 0.5, 2.5, or 5.0 μg of hormone/ml, then incubated for 30 min at 37°C. The cultures were rapidly chilled and added to equal volumes of cold 6% glutaraldehyde in 0.2 M cacodylate buffer. After 30 min, the bacteria were concentrated by centrifugation (15 min at 4000 RPM) and the pellets suspended in cold 3% glutaraldehyde for an additional 15 min, followed by centrifugation. The pellets were resuspended in cold cacodylate buffer and stored at 2°C for 1-7 d. The cells were again centrifuged and the pellets were blotted with a strip of filter paper to remove excess fluid, then mixed with a drop of warm 2% agar. The agar suspensions were pipetted into cold saline. The resulting solidified extrusions were cut by hand into 2 mm segments for further processing in 1% OsO4 (with or without en bloc staining in 2% uranyl acetate (UA) in ethanol). Following dehydration in ethanol, rinsing in propylene oxide, and encapsulation in Epon-Araldite, thin sections were examined and photographed with a JEOL-100C microscope.
Ultrastructure study of morphogenesis of nuclear polyhydrosis virus of Ectropis grisescens
Authors: Liren Zhang , Dihua Chen , Jianhong Zhang 
Published: June 2020

Ectropis grisescens Warren was a major pest of tea in central and southern area of China. A newly isolated baculovirus from the insect, the nuclear polyhedral virus of Ectronis grisescens Warren (EgW-NPV), was able to kill larvas of the insect and belong to single-embedded virus in morphology. We had reported in detail the morphogenesis and assembly of Prodenis Liture NPV, a multi-embedded baculovirus, in vivo.Recently in our laboratory electron microscopy had been used for observing and analysing the ultrastructure of fine fibres and ribosomes during morphogenesis of EgW-NPV in EgW larvas cells infected by this virus.
The structure of CF1 ATP-synthase isolated from spinach chloroplasts
Authors: Boekema Egbert J. 
Published: June 2020

F1 is the soluble part of the ATP-synthase complex, which catalyzes the synthesis of ATP. F1 is built up from five different subunits. Three copies of two large subunits α and β, with a molecular mass of about 55000, form the backbone of the protein. Spinach ATP-synthase has also three smaller subunits: gamma (35700), δ (20000) and ɛ (13000). They are located within the α3β3 structure, which can be seen as a hexagon in projection. By immuno-electronmicroscopy it was demonstrated that in the hexagonal (top view) projection the large α and β subunits are alternating.No detailed three-dimensional structure of a F1 ATP-synthase is available. Therefore, some important features of the structure are not precisely known. One example is the shape of the large subunits.
An x-ray mapping study of the effects of aluminum on the distribution of calcium, potassium and phorphorus in the roots of Hordeum vulgare var. Kearney
Authors: Nichol B. , Oliveira L. 
Published: June 2020

Alumninum toxicity in plants has been shown to reduce root length and the net uptake of nitrate, ammonium, and potassium. In contrast it was demonstrated that phosphate net uptake increased with Al treatment. Additions of calcium to the growth medium were shown to counteract these effects, particularly changes in root length. However the reason(s) for the anti-toxic effect(s) of calcium ions is not understood. One possibility is that Al displaces Ca from the plasmamembrane and/or the cell wall which in turn disrupts Ca-dependent transport processes within and on the cell surface. In this study we report on the effects of Al on Ca, K and P distribution in the roots of the barley variety Kearney using x-ray mapping of freeze-dryed material and discuss the results in terms of the general mechanism of Al toxicity.Root material was obtained from 5day old plants grown in hydroponic solution with or without 50 μM Al. Excised root tips were mounted on specimen holders and plunged into liquid nitrogen after which the roots were faced off with a cyromicrotome.
Electron Microscope studies (TEM and SEM) of in vitro multiplication of Lavandula stoechas L.: I. regeneration from seedling shoot apex explants
Authors: Mesquita J. F. , Guimarães M. L. , Santos Dias J.D. 
Published: June 2020

Available data concerning “in vitro” multiplication of Lavandula sps. are scarce and do not involve cytological studies. In this work, shoot initiation from shoot apex explants of Lavandula stoechas is analysed, for the first time, in light and electron microscopes (TEM, SEM). Following habitual sterilization, seeds of Lavandula stoechas were germinated on MS basal medium with 2% sucrose (W/v). From 9-days old seedlings, explants (shoot tips including a small distal segment of hypocotyl - fig. 1) were aseptically excised and cultivated in that basal medium added with organic components as in B5 medium of Gamborg et al., 10% (V/v) of coconut milk, 0.8% of agar and benzyl-amino-purine (BAP) at different concentrations (0-4 mg/1). The pH was adjusted to 5.6 and cultures were maintained at 25±1°C with fluorescent light (2000 lux) for 16 h/day.High frequency of multiple shoot formation was achieved on media supplemented with BAP, the concentration of 1mg/l showing to be the optimal one (Table 1).
Dictyosome tubules, a conspicuous membraneous system of the plant cell
Authors: Mollenhauer H.H. , Morré D.J. 
Published: June 2020

Tubules of about 30 run diameter are a conspicuous feature of most, if not all, Golgi apparatus cisternae (Fig. 1). The tubules may be configured as fenestrae, networks, or single outward projections around the edges of the cisternae. Coated, vesicle-like membrane buds are a common feature of tubules. Short lengths of tubules connect secretory vesicles to cisternae.The function of the tubules is not known although they interconnect cisternae of closely spaced dictyosome stacks and have been postulated to be intermediates between endoplasmic reticulum and Golgi apparatus. Additionally, they may play a part, as yet undefined, in the movement of products between cisternae.This report demonstrates that the peripheral tubules of the Golgi apparatus are a conspicuous membrane system of the cell, equal to, and often exceeding, that of the flattened parts of the Golgi apparatus cisternae.Tubules were considered as cylinders of constant diameter with total lengths equal to the sum of all tubule segments.
Surface ultrastructure of the gill arch of the Chaetodiptus faber (Broussonet, 1782) (Pisces)
Authors: Eiras-Stofella D. R. , Fanta E. 
Published: June 2020

The fish chaetodipterus faber caught at the Paranaguá bay (southern Brazil) had the gills gently removed from the right body side, rinsed with 0.9% NaCl solution, and fixed in 3% glutaraldehyde in 0.15M phosphate buffer (1:1); 1% osmium tetroxide in the same buffer was used for post fixation. After that the gill arches were rinsed and then dehydrated in a graded ethanol series, critical-point dried in liquid CO2, and coated with gold. They were viewed and photographed in a Philips scanning electron microscope.At the pharingeal region of the branchial arch, the gill raker has many hooks with sharp pointed spines (Fig. 2). Between them and at its base, many taste buds protrude. The epithelium has typical polygonal pavement cells with concentrically arranged surface ridges (Fig. 5). The respiratory lamellae are triangular in shape (Fig. 4), rising from the branchial filaments, irregular in thickness (Fig. 1). At the base some globous structures were found (g). Chloride cell apical crypts are at the surface of the epithelium.
A new method for searching intracellular stereo structures in plant tissues
Authors: Yao Yaqin , Jiang Xuanli , Hu Dongwei 
Published: June 2020

The procedure for specimen preparation consist of the following.
1.fixing the plant tissues routinely;2.washing the blocks thoroughly in PBS buffer;3.immersing the blocks in a PEG (polyethylene glycol 4000) series (50, 70, 90, 100%) and embedding in pure PEG at 50°C, and cooling slowly to room temperature;4.cutting into thin sections 5-10 nm thick by LKB-V microtome;5.washing the sections a few times in water, dehydrating in a graded ethanol series, and drying in a critical-point dryer using liquid CO2;6.sputter-coating with gold palladium; and7.investigating in a Hitachi S-450 scanning electron microscope.By this method, the distinct, uninjured intracellular stereo structures can be conveniently found without Joss of cell organelles. Moreover, there are advantages to studying their stereo relationships between various components of cells. Using wheat leaves, one can find chloroplasts, mitochondria, nuclei, nucleoli, and parts of the cytoskeleton system in the mesophyll cells and their sizes and distributions directly.