bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mucous droplets with multiple membranes in the accessory submandibular glands of long‐winged bats
Authors: Tandler Bernard , Phillips Carleton J. , Pinkstaff Carlin A. 
Published: February 2005

AbstractBackground: Certain species of bats possess two sets of submandibular glands, namely, principal and accessory. The ultrastructure and histochemistry of the accessory submandibular gland was examined in three species of long‐winged bats.Methods: Specimens of Miniopterus schreibersi and M. Magnator were live‐trapped in Thailand, and of M. inflatus were live‐trapped in Kenya. For electron microscopy, accessory submandibular lands were initially fixed in triple aldehyde‐DMSO, postfixed in osmium tetroxide, and embedded in Epon‐Maraglas. A portion of the glands collected in Thailand (M. schreibersi and magnator) was fixed in buffered formalin and embedded in paraffin. Sections of the latter material were subjected to a battery of histochemical tests for glycoconjugates.Results: Although in all three species the accessory submandibular glands have normal histological structure, the glands in two, M. schreibersi and M. magnator, were distinguished by possessing mucous droplets of unusual morphology. These droplets, whose identity as mucous was confirmed by histochemical tests for glygoconjugates, are delimited by maniflod membranes: up to 10 in M. Schreibersi and fewer, but still multiple, in M. magnator. In both species, the entire array of surface membranes may fold inward in the fashion of mitochondiral cristae, forming packets of membranes, many of which have the spurious appearance of floating free in the droplet matirix. These multipartite limiting membranes appear to originate simply by Golgi saccules and moderately large, flattened Golgi vesicles repeatedly wrapping themselves around the surface of nascent mucous droplets. During exocytosis, the outermost membrane of each mucous droplet contacts the luminal membrane, this barrie ruptures, then the remainder of the droplet—multiple membranes and matrix—either flow into the lumen or are cast out in toto. In either case, a great deal of membrane phospholipid is added to the salivea. This salivary lipid may permit these bats to consume insects that normally are able to repel predators with chemical defenses that make them unpalatable. The thrid species that we studied, M. inflatus, has mucous droplets of normal appearance, i.e., they have only one limiting membrane.Conclusions: The varying structure of mucous secretory products among the species of Miniopterus provides important clues as to the evolution of this genus as well as to the evolution of secretory cells in general. © 1994 Wiley‐Liss, Inc.
Light and TEM study of nonregenerated and experimentally regenerated scales of Lepisosteus oculatus (holostei) with particular attention to ganoine formation
Authors: Sire Jean‐Yves 
Published: February 2005

AbstractBackground: The structure of nonregenerated and experimentally regenerated scales of the holostean fish Lepisosteus oculatus and the events taking place before and during ganoine depostition on the scale surface were studied. The aim of this study was to answer the question of the origin of the ganoine in lepisosteids, the scales of which are devoid of dentine, and to compare them to ganoine formation in polypterid scales and to enamel formation in teeth.Methods: Two adult specimens were used and the scale structure was studied using light and transmission electron microscopy. Regeneration was used as an alternative to the lack of developmental stages and to induce ganoine deposition on the scale surface.Results: Nonregenerated scales are composed of a thick, avascular bony plate capped by ganoine that is covered either by the epidermis or by dermal elements. The ganoine surface is separated from the covering soft tissues by an unmineralized layer, the ganoine membrane. During the first 2 months of regeneration, the bony plate forms. It differs from the bony plate of nonregenerated scales only by its large, woven‐fibered central region and by the presence of numerous vascular canals. Shortly before ganoine deposition, the osteoblasts cease their activity and an epithelial sheet comes to contact them and spreads on the bony surface. This epithelial sheet is connected to the epidermis by a short epithelial bridge only and is composed of two layers: the inner ganoine epithelium (IGE), in contact with the bone surface and composed of juxtaposed columnar cells that synthesize the ganoine matrix, preganoine; the outer ganoine epithelium (OGE), composed of elongated cells, the surface of which is separted from the overlying dermal space by a basal lamina. Isolated patches of preganoine are deposited by the IGE cells in the upper part of the osteoid matrix of the scale. The interpenetrated preganoine and osteoid matrices constitute an anchorage zone, between ganoine and bone. Preganoine patches fuse and a continuous layer of preganoine is progressively synthesized by the IGE cells. Preganoine progressively mineralizes to become ganoine.Conclusions: The processes of ganoine formation are similar to those known for the ganoine in the polypterid scales and to those described for enamel deposition in teeth. Ganoine is enamel. © 1994 Wiley‐Liss, Inc.
Distribution of macrophages in the mouse uterus from one day to three months after parturition, as defined by the immunohistochemical localization of the macrophage‐restricted antigens F4/80 and macrosialin
Authors: Brandon Janet M. 
Published: February 2005

AbstractBackground: The morphology of placental detachment sites and the distribution of macrophages were studied in the mouse uterus from day 1 to 3 months post partum.Methods: Uterine morphology was studied using H&E and Mallory's Trichrome staining. Macrophages were identified using the macrophage‐restricted antigens F4/80 and FA/11 and the leukocyte β2‐integrin CR3 (Mac‐1) which is also expressed by neutrophils.Results: The post‐partum wound was infiltrated by large numbers of CR3+ F4/80+ FA/11+ macrophages, and CR3+ neutrophils. The wound resolved rapidly and no inflammatory infiltrate or necrotic tissue was seen by day 5 post partum. The area of the detachment wound and the site of the metrial gland of pregnancy resolved into a structure, here called a postpartum nodule, which persisted for at least three months. The post‐partum nodule consisted of an outer layer of collagen around a group of nodule‐specific cells which could be divided into haemosiderin‐ and lipid‐bearing phenotypes. The lipid‐bearing nodule cells were not found after day 20 post partum. Nodule cells were FA/11+ at all times and also expressed leukocyte common antigen. Expression of CR3 and F4/80 was found on nodule cells up to day 9–10 post partum. CR3 expression was found only occasionally after day 10.F4/80 expression was downregulated from day 9–10 to day 20 but was found consistently after day 20. Implantations of second and subsequent pregnancies are known not to occur in the immediate vicinity of post‐partum nodules and nodules from successive pregnancies were seen to be separate within the uterus.Conclusions: Since the endometrial area in the immediate vicinity of nodules is inimical to implantation and nodules consist of a group of macrophages, it can be implied that nodule macrophages are exerting some influence on the endometrium in their vicinity. © 1994 Wiley‐Liss, Inc.
Structural, morphometric, and immunohistological study of the accessory olfactory bulb in the dog
Authors: Salazar Ignacio , Cifuentes José M. , Quinteiro Pablo Sánchez , Caballero Tomás Garcia 
Published: February 2005

AbstractBackground: The study of the morphological, morphometric, and immunohistological characteristics of the accessory olfactory bulb (AOB) in the dog is the main goal of this work.Methods: Horizontal sections of the AOB where stained by four different methods (haematoxilin/eosin, Tolivia, Nissl, and Bielchowsky). The avidinbiotin‐peroxidase complex (ABC) was used, whereas the monoclonal antibodies to neuron‐specific enolase, neurofilaments, glial fibrillary acidic protein, and synaptophysin were selected for the immunohistological study. A computer‐assisted image analysis was employed in order to define the morphometric characteristics of de AOB.Results: The general morphology of the AOB indicates that it comprises a thick glomerular layer and a thinner internal layer containing mitral/tufted, granular, and glial cells. The mitral/tufted cells have large palestaining nuclei with intensely staining nucleoli. There does not appear to be a clearly defined granular layer. No reactivity with antibodies to neuronspecific enolase or to neurofilaments was observed in any part of the AOB, but there was some reactivity with an antibody to glial fibrillary acidic protein and widespread reactivity with an antibody to synaptophysin.Conclusions: The stratification of the AOB is simpler and less well defined than that of the main olfactory bulb (MOB), unlike in rodents in which the structure of the AOB corresponds closely to that of the MOB. According to the scale of Frahm and Bhatnagar (1980. J. Anat., 130: 349–365) the AOB of the adult dog has an intermediate position. © 1994 Wiley‐Liss, Inc.
Functional allometry of the semicircular ducts in subterranean mole‐rats Cryptomys (Bathyergidae, rodentia)
Authors: Lindenlaub Thies , Burda Hynek 
Published: February 2005

AbstractBackground: Since the spatial mobility of subterranean mole‐rats is restricted and their skull strongly modified, morpho‐functional regression of their vestibular organ may be expected. On the other hand, vestibular sense may be indispensable for orientation in a world deprived of most external sensory cues. Since vestibular sensitivity is determined by the size of the labyrinth, morphometrical analysis may be employed to assess the sensitivity and to test whether the organ is degenerate or progressively specialized.Methods: We analyzed the shape and size of the membranous labyrinth of vestibular organs in toto in three species of African subterranean blind mole‐rats of the genus Cryptomys (Bathyergidae) differing in body size yet not in habitats, ways of life, or employed orientation and locomotory strategies. The mechanical sensivity of the cupula was estimated according to Oman et al. (1987. Acta Otolaryngol. (Stockh.), 103:1–13) for each of the three semicircular ducts.Results: The size and shape of the vestibular organ changed predictably depending on species‐specific (yet not individual) body mass. In some aspects, particularly the cross‐sectional area, the ducts were larger than expected for a mammal of a comparable body size. In all species examined, the anterior semicircular ducts exhibited the highest sensitivity.Conclusions: The vestibular organs of blind subterranean mole‐rats are not regressed morpho‐functionally. © 1994 Wiley‐Liss, Inc.
Ultrastructural and immunocytochemical study on normal human palmar aponeuroses
Authors: Contri Miranda Baccarani , Guerra Deanna , Vignali Nicoletta , Taparelli Francesca , Marcuzzi Augusto , Caroli Alessandro , Ronchetti Ivonne Pasquali 
Published: February 2005

AbstractBackground: Human palmar aponeurosis can be affected by a fibrotic process whose aetiopathology is unknown. As the organization of that normal tissue has not been completely investigaged, the aim of the present study was to define the ultrastructure of the aponeurosis in order to better understand its biology and behaviour in pathology.Methods: Bioptic samples from normal subjects of different ages were analyses by optical and electron microscopy and by immunocytochemistry.Results: The aponeurotic branches consisted of thick, almost parallel collagen bundles containing columns of prominent cells, characterized by long cytoplasmic projections. Cells did not change in number and distribution with age and appeared longer and slighter in the old than in the young subjects. They exhibited plasma membrane almost completely decorated by pinocytic vesicles, intracytoplasmic bundles of thin filaments with zonal thickenings close to the cell membrane, and well‐developed subcellular structures. Cells expressed smooth muscle cell α‐actin, as revealed by immunostaining. The external surface of the plasma membrane was underlined by a discontinuous basement membrane–like structure and by a thick coat of interwoven filaments, highly positive to hyaluronan‐recognizing antibodies. Immunocytochemical analyses revealed that collagen fibrils were positive for collagen types I, III, and VI and that elastin fiber composition was rather complex.Conclusions: Independently of the age, normal palmar aponeurotic cells show peculiar morphological features and peculiar cell‐matrix interactions, very likely mediated by hyaluronan. These findings indicate that normal aponeurotic cells cannot be regarded as typical tenocytes and suggest the need for a better definition of their phenotype in order to understand their behaviour in pathological processes. © 1994 Wiley‐Liss, Inc.
Immunolocalization of a mesenchymal antigen specific to the gastrointestinal tract
Authors: Calvert Raymond , Millane Ghania , Beaulieu Jean‐François 
Published: February 2005

AbstractBackground: The aim of the present study was to localize, at the fine structural level, a protein found by indirect immunofluorescence to be associated with the mesenchymal tissue (1) closely applied to the intervillus epithelium before the formation of intestinal crypts in the mouse fetus and (2) around intestinal crypts during and after their formation.Methods: We use a pre‐embedding immunolabeling technique for extracellular matrix molecules, and a monoclonal antibody (Mab) directed against antigen MIM‐1/130.Results: Immunofluorescence disclosed the presence of antigen 1/130 in the connective tissue closely applied to the epithelium of the gallbladder, pyloric glands, and intestinal and colonic crypts in adult mice. The antigen was absent in all salivary glands, kidney, liver, lung, spleen, and pancreas. At the fine structural level, gold particles in positive organs were associated with the interstitial matrix around collagen fibrils underneath the epithelia; gold particles were completely absent in the basement membranes. In the small intestine, labeling was seen only around crypts from cell position 1 up to the crypt‐villus junction; it was totally absent under the villus epithelium. In order to confirm this particular localization in vivo, Mab 1/130 was administered orogastrically to 9‐day‐old mice: after 3 hours the antibody was found lining the immediate periphery of duodenal crypts as seen by indirect immunofluorescence. In control animals, an anti‐mouse laminin Mab of the same subclass as Mab 1/130 was orogastrically fed using the same protocol: basal laminae were labeled under the epithelium of duodenal villi and crypts and also in the lamina propria, with a decreasing gradient from the top of the villi to the bottom of the crypts.Conclusion: These observation indicate that the extracellular matrix associated with the epithelium of pyloric glands, of intestinal and colonic crypts, and of gallbladder contains a new antigen whose function remains to be determined. The neonatal mouse hence constitutes a good model to study the role of extracellular matrix components in determining organ differentiation in vivo. © 1994 Wiley‐Liss, Inc.
Observations on the pineal gland of the big brown bat, Eptesicus fuscus: Possible correlation of melanin intensification with constant darkness
Authors: Bhatnagar Kunwar P. , Hilton Frederick K. 
Published: February 2005

AbstractBackground: Our initial observation of the macroscopically pigmented pineal gland of the big brown bat, Eptesicus fuscus, led to this study. Information has been lacking on pigmentation in the pineal and its significance in mammals in general and bats in particular. This report begins to address this situation.Methods: Bats were examined both in the wild and after exposure to various experimental conditions. The pineals were examined macroscopically as well as with light and electron microscopy. The pigment was identified as melanin by its color, the ultrastructure of its granules, and their reaction with hydrogen peroxide.Results: Gross observations showed the pineals to be variably pigmented, which were subjectively scored from unpigmented to heavily pigmented. Pineals from bats exposed to a continuous 24 h light regimen or those from a summer population contained very little, if any, externally visible melanin. Such pineals are considered unpigmented in this study. In contrast, pineals from 74% of 156 animals taken together, either subjected to constant darkness or hibernation (simulated or natural), exhibited very heavily pigmented pineals. The pigment in these cases even extended to the juxtapineal meningeal covering. The pineal was pigmented even in a newborn Eptesicus.Conclusions: The pineal pigmentation in the big brown bat appears to intensify with constant darkness and may vary seasonally. The observation of macroscopically pigmented pineals in some other bats (Myotis lucifugus, Pipistrellus subfiavus, and Lasiurus borealis) suggests that this phenomenon may be of taxonomic value for the family Vespertilionidae (Order Chiroptera). © 1994 Wiley‐Liss, Inc.
Composition of Gomori‐positive inclusions in astrocytes of the hypothalamic arcuate nucleus
Authors: Brawer James R. , Stein Robert , Small Lorne , Cissé Soriba , Schipper Hyman M. 
Published: February 2005

AbstractBackground: Astrocytes within the hypothalamic arcuate nucleus contain Gomori‐positive inclusions that exhibit a nonenzymatic peroxidase activity. The source and composition of these Gomori‐positive inclusions are currently unknown. Recent evidence, derived from cultured astrocytes, suggests that Gomori‐positive inclusions may consist of autophagocytized accumulations of altered mitochondria and that the peroxidase activity is generated by iron or other metals which accumulate in these mitochondria.Methods: The present study applies electron microscopy, energy dispersive X‐ray microanalysis, and immunocytochemistry in conjunction with confocal microscopy to determine the structure and composition of Gomori‐positive inclusions in vivo.Results: The results indicate that Gomori‐positive inclusions are heterogeneous structures often associated with microtubules and that they contain conspicuous mitochondrial components. Gomori‐positive inclusions exhibit X‐ray emission peaks for copper and, less often, chromium, either of which could account for the peroxidase activity.Conclusions: These results support the hypothesis that Gomori‐positive inclusions are autophagosomes in which mitochondria are prominent. © 1994 Wiley‐Liss, Inc.
Scanning electron microscopic studies of reticular framework in the rat mesenteric lymph node
Authors: Ushiki Tatsuo , Ohtani Osamu , Abe Kazuhiro 
Published: February 2005

AbstractBackground: The reticular framework in the lymph node has in the past been studied mainly by light microscopy of silver‐impregnated specimens. The aim of the present study is to understand three‐dimensionally the ultrastructure and organization of the reticular framework better than before.Methods: The mesenteric lymph nodes of the rat were prepared either an alkali‐water maceration method or a conventional method and were observed in a scanning electron microscope (SEM).Results: The SEM study of alkali‐water macerated tissues visualized directly the reticular fiber network in the lymph node. The reticular fibers consisted of thin bundles of collagem fibrils. They were continuous with the collagen fibriliar sheaths of blood vessels and lymphatic sinuses as well as with the fibrous capusule, thus acting as a skeleton of the lymph node. The arrangement of the reticulum was variable, depending on individual compartments. The SEM study of conventionally treated tissues, on the other hand, clarified the shape of reticular cells and their relationship with the reticular fibers. The sinus reticular cells connected with the sinus lining cells but separated from the parenchymal reticular cells, indicating that the former two originate from lymphatic endothelial cells. The parenchymal reticular cells varied in shape depending on their locations but essentially shared features with fibroblasts.Conclusions: The arrangements of the reticular fibers in the parenchyma were closely related to the associated reticular cells, showing the possibility that the reticular cells maintain the shape of the reticular framework suitable for each compartment of the lymph node. © 1995 Wiley‐Liss, Inc.
Regeneration in denervated toad (bufo viridis) gastrocnemius muscle and the promotion of the process by low energy laser irradiation
Authors: Bibikova Anna , Oron Uri 
Published: February 2005

AbstractBackground: It is known that while denervated skeletal muscles have the ability to regenerate, maturation of regenerated myofibres does not take place under these conditions. Denervation also causes elevation of “invasive” and satellite cells, but the role of these cells in the regeneration process after injury to the denervated muscle is still unknown. Low energy lasers have recently been found to modulate and accelerate physiological processes in cells. The aim of the present study was to compare regeneration in denervated and innervated amphibian muscles and to investigate whether this process in denervated muscles can be stimulated by low energy laser irradiation prior to injury in these muscles.Methods: Denervated gastrocnemius muscles of toads were irradiated with He‐Ne laser (6.0 mW, 31.2 J/cm2) 7 days postdenervation (control muscle received red light irradiation at the same wavelength). Nine days after denervation cold injury was performed on the site of irradiation of both groups of muscles. At 14 days postinjury all muscles were removed and processed for histology and histomorphometric analysis of mononucleated cells, myotubes, and young myofibres in the regenerated zone.Results: The volume fraction (percent of total injured zone) of the various histological structures in the injured zones 14 days after cold injury in the denervated (9 days prior to injury) muscles did not differ from innervated injured muscles at the same time interval postinjury. The mononucleated cells and myotubes in the laser irradiated muscles comprised 49 ± 4% and 6 plusmn; 1% of the injured area, respectively, which was significantly lower than their volume fraction (67 plusmn; 2% and 11 plusmn; 2%, respectively) in the control muscles. The young myofibres populated 34 plusmn; 4% of the total injured area in the denervated and laser irradiated muscles which was significantly higher than their volume fraction (12 ± 2%) in control denervated muscles.Conclusions: It is concluded that initial stages of regeneration can also take place in skeletal denervated and injured muscles of amphibians. The kinetics of the regeneration process are identical in denervated and innervated muscles. The process of regeneration in denervated muscles can be markedly enhanced if the muscle is irradiated by low energy laser prior to injury, probably by activation (stimulation of proliferation and/or differentiation) cells in the muscles that are “recruited” and participate in the process of regeneration. © 1995 Wiley‐Liss, Inc.
Morphometry of rat germ cells during spermatogenesis
Authors: De Franca Luiz Renato , Ye Shi‐Jun , Ying Li , Sandberg Megan , Russell Lonnie D. 
Published: February 2005

AbstractBackground: There has never been a study of the components of germ cells as they progress through spermatogenesis.Method:The structural changes taking place in rat germ cells, from spermatogonia to late supermatids, were studied utilizing morphometric techniues conducted largely at the ultrastructural level.Results:Volume and surface area parameters for virtually all cellular and subcellular features were obtained for nine periods during the spermatogenic cycle. Virtually of germ cell components show dynamic properties associated with specific phases of their development.Conclusions: The data provided can be used in an objective wey to characterize structural changes to funcational properties of germ cells. © 1995 Wiley‐Liss, Inc.