bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis and expression of laminin during human foetal lung development
Authors: Lallemand Aude V. , Ruocco Sandrine M. , Gaillard Dominique A. 
Published: February 2005

AbstractBackgrounds: The lung develops by epithelial tubes budding and branching into a flexible mesenchyme. This growth is associated with the remodelling of the epithelial basement membrane, of which laminin is a major component. Methods: Both the synthesis and expression of laminin were studied in the human lung between 10 and 31 weeks of gestation, using in sity hybridization and immunohistochemistry. Results: The synthesis of the β chain was active in the epithelial and surrounding mesenchymal cells. The mRNAs coding for the γ chain were less abundant and mainly found in the epithelium. The synthesis of these two chains continued throughout gestation, and no significant difference in the density of hybridization grains could be detected between the tips of the expanding buds and the proximal portions. Immunohistochemical localization of laminin showed important modifications of the basement membrane during gestation. In the first part of the pseudoglandular stage the epithelial basement membrane stained continuously for laminin. Later, the basement membrane was labelled in a graded fashion: at the apex of the growing buds the staining became weak with focal disruptions. Both epithelial and mesenchymal synthesis of laminin remained active, while the polypeptide was undetectable using immunohistochemistry. Conclusions: These findings suggest that the remodelling of the basement membrane during human lung morphogenesis is probably not related to a decreasing synthesis of laminin, but to either a proteolytic degradation or the assembly of an inadequate complex undetectable with the polyclonal antibody antilaminin. © 1995 Wiley‐Liss, Inc.
Trans‐Golgi network (TGN) of different cell types: Three‐dimensional structural characteristics and variability
Authors: Clermont Y. , Rambourg A. , Hermo L. 
Published: February 2005

AbstractBackground: The trans‐Golgi network (TGN) is generally considered as a distinct and permanent structural compartment of the Golgi apparatus of various cell types. To verify this postulate we examined and compared the three‐dimensional characteristics of the TGNs of 14 different mammalian cell types as presented in our various publications since 1979 when we initially described the trans‐tubular network of Sertoli cells.Methods: In all these studies we used low and high voltage electron microscopes on thin or thick sections of tissues fixed with glutaraldehyde and postfixed with reduced osmium. The section were stained with uranyl acetate and lead citrate. Stereopairs, prepared from photographs of tilted specimens, permitted a direct observation of the three‐dimensional structure of the various elements of the Golgi apparatus.Results: The TGNs are multilayered and extensive in cells which do not form large typical secretory granules (Sertoli cells, nonciliated cells of ductuli efferentes, spinal ganglion cells) but have an extensive lysosomal system. The TGN is absent in cells forming very large secretory granules (secretory cells of seminal vesicles and lactating mammary glands). The TGNs are small in cells producing small to medium‐size secretory granules and/or appear as residual fragments on the trans aspect of the Golgi stacks (e.g., mucous cells of Brunner's gland, pancreatic acinar cells, etc.). In cells with multiple and extensive TGNs, a continuity of these tubular networks with the two or three transmost saccules of the stack is observed but there are seemingly no connections between the TGNs. Whenever the TGNs are present, they do not form a continuous structure along the Golgi ribbon. However, they do present, in all cases, configurations suggestive of desquamation and renewal.Conclusions: The structure of the TGN varies considerably from one cell type to another, being extensive in cells not showing typical secretory granules but having an extensive lysosomal system, while in secretory cells showing small or large secretory granules the TGN is either small or even entirely absent. © 1995 Wiley‐Liss, Inc.
Distribution of epithelioid cells in the wall of the chicken aorta and their functional role as chemoreceptors
Authors: Miyoshi Masakazu , Hashimoto Yoshiharu , Kon Yasuhiro , Sugimura Makoto 
Published: February 2005

AbstractBackground: The ultrastructural characteristics of epithelioid cells in the wall of the chicken aorta have been studied by several investigators. Their characteristics were homologous to those of carotid body type I cells and are considered to be one of the peripheral chemoreceptors. However, there are few descriptions about their location, distribution, and how they react to chemical signals, nor have there been many reports about the localization of bioactive substances in the epithelioid cells. Therefore we designed this investigation to address these problems.Methods: Wholemount immunohistochemistry using antiserotonin antiserum, scanning (SEM), and transmission (TEM) electron microscopy were used to observe the epithelioid cells and the lumen of the chicken aorta. The localizations of bioactive substances in the epithelioid cells were immunohistochemically investigated using 11 antisera.Results: Epithelioid cells were dispersed in the wall of the aorta, forming a band ∼1 mm in width, located 10 mm proximal to the confluence of the right and left ligamenta arteriosa. Serotonin, chromogranin, and neuron specific enolase immunoreactivities were detected in the epithelioid cells. SEM observations clearly demonstrated intraendothelial fenestrations, 1–3 μm in diameter, on the endothelial surface of the region of the band of epithelioid cells. TEM observations revealed that these fenestrations corresponded to endothelial gaps, directly beneath which epithelioid cells were sometimes located.Conclusions: The epithelioid cells are in direct access to the aortic lumen through endothelial fenestrations. Thus they may be able to perceive chemical signals from arterial blood directly. © 1995 Wiley‐Liss, Inc.
Anatomy of the sinus node, av node, and his bundle of the heart of the sperm whale (Physeter macrocephalus), with a note on the absence of an os cordis
Authors: James Thomas N. , Kawamura Keishiro , Meijler Frits L. , Yamamoto Shoji , Terasaki Fumio , Hayashi Tetsuya 
Published: February 2005

AbstractBackground: Atrioventricular (AV) conduction time in large whales is only slightly greater than in smaller mammals even though their hearts are enormously larger. Little is known of the detailed histology or cytology of the conduction system of large whales. Such knowledge could be useful in defining the nature of cardiac rhythm and conduction of the whale as well as smaller mammals including humans.Methods: We studied hearts from seven sperm whales. After fixation in formaldehyde and later dissection, specimens were prepared for histological examination.Results: Cell size, histological organization, and innervation of the sperm whale's sinus node, AV node, and His bundle are similar to most mammalian hearts, except the sinus node is substantially larger. There is no central fibrous body between the atrial and ventricular septa, and the whale has no os cordis. Only the upper quarter of the interventricular septum is fully formed; below that there is only a thin layer of fatty connective tissue between the two ventricles.Conclusions: Given our morphological findings, we believe that the whale's comparatively short AV conduction time may be best explained by the sinus node and AV node functioning as coupled relaxation oscillators. Absence of an os cordis or central fibrous body or strong attachment between the two ventricles may pose both electrophysiological and hemodynamic hazards when the whale is no longer in its normally buoyant aquatic environment. © 1995 Wiley‐Liss, Inc.
Histamine release from Weibel‐Palade bodies of toad aortas induced by endothelin‐1 and sarafotoxin‐S6b
Authors: Doi Yoshiaki , Ozaka Takatoshi , Katsuki Masatsugu , Fukushige Hiroshi , Toyama Eiichiro , Kanazawa Yosuke , Arashidani Keiichi , Fujimoto Sunao 
Published: February 2005

AbstractBackground: Endothelin‐I (ET‐1) and sarafotoxin‐S6b (STX) induce a remarkable degranulation of Weibel‐Palade (WP) bodies prior to the vasocontraction of toad aortas. As WP bodies play the role of a reservoir site of the histamine in the endothelial cells, there is the possibility that ET‐1 and STX evoke the release of histamine from WP bodies of this vessel.Methods: Histamine concentrations were assayed by high‐performance liquid chromatography (HPLC) from the perfusate after being perfused with a solution containing ET‐1 and STX. Each vessel was fixed and embedded for conventional electron microscopy and immunoelectron microscopy using antihistamine sera.Results: The appreciable concentrations of histamine were assayed by HPLC from the perfusate after the toad aortas were perfused with a solution containing ET‐1 and STX. The immunoelectron microscopy revealed that histamine immunoreactive gold particles in the WP bodies remarkably decreased in number in the treated samples when compared to the control ones. Our immunoelectron micrographs indicated that the release of histamine from the endothelial cells occurred in association with the degranulation and the exocytosis of the WP bodies after treatment with ET‐1 and STX.Conclusions: The present study clearly shows that ET‐1 and STX induce the histamine release from WP bodies of the toad aortas by means of HPLC and immunoelectron microscopy. Histamine discharged from the WP bodies may be involved in the vasocontraction evoked by ET‐1 and STX. © 1995 Wiley‐Liss, Inc.
Corrosion casting study on the vasculature of nasal mucosa in the human fetus
Authors: Składzień J. , Litwin J. A. , Nowogrodzka‐Zagórska M. , Miodoński A. J. 
Published: February 2005

AbstractBackground: The vasculature of the nasal mucosa in the human fetus so far has not been investigated morphologically by modern techniques.Methods: Nasal blood vessels were studies in 18–21‐week‐old human fetuses by corrosion casting and scanning electron microscopy.Results: The general vascular architecture was similar to that described for adult humans, with (1) a dense network of subepithelial capillaries, (2) a mucosal layer of larger vessles, predominantly veins, and (3) large arteries located near the perichondrium. Specific vessel types characteristic of the nasal mucosa and important for its functions in adults, such as cavernous veins or cushion veins, were, however, absent in the fetuses, although probable precursor forms of cushion veins could be observed. The arteriovenous anastomoses had the form of short bridges, and no tortuous or glomerular anastomoses present in the mature nasal mucosa were found.Conclusions: The underdevelopment of some vascular areas is postulated to reflect the functional immaturily of the respiratory system in the fetus. © 1995 Wiley‐Liss, Inc.
Morphology of the dorsal phalangeal connective tissue body
Authors: Bade Holger , Schubert Markus , Koebke Jürgen 
Published: February 2005

AbstractBackground: The connective tissue body of the dorsal finger is partitioned by multiple horizontal lamellae derived from expansions of intercellular spaces. These connective fibres are involved in providing gliding spaces for the extensor apparatus, and they formed spreading rooms of infection processes.Methods: In order to describe the topographical histological and histochemical behavior of cellular and intercellular elements of the border lamellae of the dorsal aponeurosis of the fingers, a modified method of Epoxid resin embedding technique without pre‐infiltration is used.Results: The bordering elements of the connective tissue lamellae described in this investigation are especially well defined in the region of the dorsal aponeurosis. The morphological examinations show that both the expansions of the intercellular space as well as defined fibrocytic cellular elements function in a manner equivalent to a synovial membrane of tendon sheaths.Conclusions: Saving or reconstructing these structures appears to be of importance in preventing for adhesive disorders of finger motion following surgical intervention in this region. © 1995 Wiley‐Liss, Inc.
Morphometric characterisation of the fine structure of human type II pneumocytes
Authors: Fehrenbach Heinz , Schmiedl Andreas , Wahlers Thorsten , Hirt Stefan W. , Brasch Frank , Riemann Dörte , Richter Joachim 
Published: February 2005

AbstractBackground: Pulmonary type II pneumocytes have been examined by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and morphometry in numerous mammals. Until now, the fine structure of the human type II pneumocyte has not been studied by means of morphometry.Methods: Eleven human donor lungs, which could not be made available for a suitable recipient, were preserved with Euro Collins solution (ECS) according to clinical organ preservation techniques. The lungs were fixed via the airways. Systematic random samples were analyzed by SEM, TEM, and classical stereological methods.Results: Type II pneumocytes showed normal fine structural characteristics. Morphometry revealed that although inter‐individual variation due to some oedematous swelling was present, the cells were in a normal size range as indicated by an estimated mean volume of 763 ± 64 μm3. The volume densities were: nucleus 21.9 ± 2.2%, mitochondria 5.8 ± 0.9%, lamellar bodies 9.8 ± 3.6%, and remaining cytoplasmic components 62.4 ± 2.9% of the cell volume. Since the inter‐individual variations in the volume densities referred to the cell may, to variable degrees, reflect the variation in the reference space, the volume densities referred to the constant test point system and the respective volume‐to‐surface ratios were used for interindividual comparisons. These parameters indicate that lamellar bodies were independent of cellular swelling, while mitochondria nucleus remaining cytoplasmic components increased in size with increasing cell size.Conclusions: Two to 7.5 hours of cold ischemia following ECS preservation do not deteriorate the fine structure of type II pneumocytes of human donor lungs. For reliable assessment of fine structural variation, morphometric parameters are required that are independent of variations in cell size. © 1995 Wiley‐Liss, Inc.
Organization and cytology of lymphoid tissue in the cynomolgus monkey conjunctiva
Authors: Ruskell G. L. 
Published: February 2005

AbstractBackground: Knowledge of the structure of conjunctival lymph follicles is limited in comparison with those of other mucosa. Consequently a thorough morphological study of the follicles was undertaken to see if they are similar to others or whether they have any unique features and to provide an adequate background for future experimental studies.Methods: Normal lymphoid tissue of the conjunctiva of one side of nine young adult cynomologus monkeys was examined using a whole mount method and light and electron microscopy.Results: Only the peripheral tarsal and orbital regions of the upper and lower palpebral conjunctiva contained lymph follicles. Lymphocytes, reticulocytes, macrophages including tingible body macrophages, putative follicular dendritic cells, and plasmacytes were indentified in the follicles and M‐cells were present in the follicle associated epithelium. High endothelial venules (HEV) displaying evidence consistent with lymphocyte extravasation were present in both primary and secondary follicles. A majority were secondary follicles with a germinal center composed largely of lymphoblasts. Mitoses were found in secondary follicles, mostly confined to the germinal centers, and they were numerous in many. Increased cell density and virtual elimination of intercellular space adjacent to some high endothelial venules suggested a possible association of these vessels with germinal center development. Chains of follicles were linked by lymph vessels, an approaching lymphatic dividing to embrace a follicle and recombining beyond it and passing to the next in line; many conjunctival follicles there‐fore have both afferent and efferent lymphatics. The vessels were in direct contact with the follicle perimeters; lymph capillaries were not present within the substance of most follicles. Numerous valves indicated drainage radially from the tarsal conjunctiva then laterally or medially from the orbital conjunctiva through the follicle chains towards the nearest canthus.Conclusions: Conjunctival lymph follicles are fundamentally similar in structure to those found elsewhere in the body. However, the beads on a chain‐like arrangement of lymph vessels and follicles may be unique. The possible association of HEV with follicle foramtion could be a general characteristic of mucosal follicles. ©1995 Wiley‐Liss, Inc.
Cytoskeletal architecture of rat calvarial osteoclasts: Microfilaments, intermediate filaments, and nuclear matrix as demonstrated by detergent perfusion
Authors: Watanabe Hiroki , Yanagisawa Takaaki , Sasaki Junzo 
Published: February 2005

AbstractBackground: There have been few detailed transmission electron microscopic studies of the cytoskeleton of osteoclasts to date because of the high electron density of their cytoplasmic matrix, and there is a controversy concerning the presence of stress fibers in these cells.Methods: The cytoskeleton and nuclear matrix of osteoclasts in the rat cranium were studied by transmission electron microscopy after perfusing the organs with a mixture of Triton X‐100 and a low concentration of glutaraldehyde to reduce the electron density of the intracellular matrix and by immunoelectron microscopy using anti‐actin and anti‐vimentin antibodies.Results: In osteoclasts, abundant microfilaments, 5 – 6 nm in diameter, extended across the cell organelles. These filaments were also observed just under the cell membrane facing the bone, but thick bundles of microfilaments were not noted. In the cytoplasm, there were fibers 10–12 nm in diameter, which were considered to be intermediate filaments distributed in the same pattern as microfilaments. Filamentous structures consisting both of the microfilaments and intermediate filaments connected the nuclei. Intermediate filaments linked nuclei at nuclear pores (near the euchromatin), and microfilaments connected nuclei at areas of the nuclear membrane containing nucleolus‐associated heterochromatin. In the nuclear matrix after detergent treatment, thin filaments and intermediate ‐type filaments were found connecting the heterochromatins.Conclusions: Euchromatin is considered to be an active site of DNA and RNA synthesis. Our structural evidence has lead to the proposal that intermediate filaments in the cytoplasm may act as tracks for transmission of information between nuclei and guides for the transit of molecules through the pores. © 1995 Wiley‐Liss, Inc.
Morphomechanics of the humero‐ulnar joint: I. Joint space width and contact areas as a function of load and flexion angle
Authors: Eckstein Felix , Löhe Florian , Hillebrand Susanne , Bergmann Mathias , Schulte Erik , Milz Stefan , Putz Reinhard 
Published: February 2005

AbstractBackground: Previous studies have shown that the trochlear notch is deeper than necessary for an exact fit with the humerus. However, humero‐ulnar joint space width and contact areas have so far not been quantified for variations in the load and angle of flexion.Methods: Six fresh cadaveric specimens were investigated at 30°, 60°, 90°, and 120° of flexion and at loads of 25 and 500 N, simulating resisted elbow extension. The joint space width and contact were determined, using polyether casting material.Results: At 25 N all joints made contact in the ventral and dorsal aspects of the articular surfaces, whereas in the depth of the trochlear notch the joint space was on average between 0.3 and 2.8 mm wide, with some variation between individuals. At 500 N the joint space width was considerably reduced and the contact areas expanded towards the depth of the notch. The size of the dorsal contact areas was significantly smaller at 30° and that of the ventral ones at 120°, their ventro‐dorsal ratio decreasing considerably from 30° to 120° (P< 0.01).Conclusion: These results indicate that the size of the contact areas depends to a slight extent on the joint position, but that at all loads and flexion angles a bicentric contact and an important central joint space width emerge because of the concave incongruity of the joint, These data may be used for numerical calculations, analysing the effects of incongruity on the joint stress and on the functional adaptation of the subarticular tissues. © 1995 Wiley‐Liss, Inc.
Culture of bovine oviduct epithelial cells (BOEC)
Authors: Walter I. 
Published: February 2005

AbstractBackground: Bovine oviduct epithelial cells are widely used in co‐culture experiments to improve early embryonic development and in vitro fertilization in embryo transfer programmes for domestic animals.Methods: The present study compares different methods for harvesting and culture of bovine oviduct epithelial cells in order to optimize handling. Bovine oviduct epithelial cells were mechanically or enzymatically isolated and cultured on glass, on permeable membranes, or in suspension. Growth of the cells and their state of differentiation was examined by means of classical staining methods, immunohistochemistry and electron microscopy.Results: Initial cell suspensions contained sheets of ciliated and nonciliated (secretory) cells; 24 h after seeding, free floating epithelial cells formed vesicles with cilia on their external surface. First adhesion of cells was seen 72 h after seeding. Later on, cells grew continuously and confluent monolayers were formed after 7 days. Results were identical after mechanical or enzymatical cell harvesting and were identical on both substrata tested, i.e., on glass and on permeable membranes. Light and electron microscopy proved the monolayers to resemble a polarized, simple, cuboidal to columnar epithelial membrane with intact junctional complexes and numerous apical microvilli. Their epithelial nature was established by immunostaining for cytokeratins. Cilia were missing and secretory granules were scarce. A layer of acidic glycoprotein material was demonstrated on the apical surface. Monolayers of bovine oviduct epithelial cells stored lipid droplets and large quantities of glycogen. About 50% of the seeded cells did not adhere but survived in the culture medium as free floating cells. These suspended cells maintained morphological criteria of differentiation (cilia and secretory granules) until day 12 of culture. Proliferation rates of cultivated cells were determined by counting mitoses and by immunostaining with MIB1 antibody. Results showed coincidence of rapid proliferation and morphological dedifferentiation of monolayers. Suspended cells, by contrast, did not proliferate but retained cellular differentiation under identical culture conditions.Conclusions: The results strongly suggest that monolayers of bovine oviduct epithelial cells will not fully substitute for original oviduct epithelium when used in co‐culture experiments after in vitro fertilization. © 1995 Wiley‐Liss, Inc.