bluuebunny/crossref_metadata_2025_split huggingface dataset:
Basal cells in human bronchial epithelium
Authors: Baldwin Frank 
Published: February 2005

AbstractThe morphology and distribution of basal cells were investigated in adult human bronchial epithelium.In both smokers and non‐smokers typical basal cells were more numerous than atypical basal cells, which were distinguished by their spindle‐shaped nucleus, polar cytoplasm, and processes that extended along the basal lamina. The nucleus of the atypical basal cell was consistently closer to the muco‐ciliary surface than was the nucleus of the typical basal cell.In cross‐sections of bronchi the numbers of typical basal cells/mm epithelium were greatest in large airways; in smaller bronchi (i.e., generations 7–16) the frequency declined. The numbers of atypical basal cells/mm epithelium were similar throughout the bronchial tree.Throughout the bronchial tree both types of basal cells contributed to the maintenance of epithelial cohesion by providing desmosomal attachment for columnar cells. The importance of typical basal cells in this role was indicated by their greater numbers, which collectively presented a large surface for epithelial cell attachment by desmosomes. The surface presented by the cell body and processes of each atypical basal cell for attachment of columnar cells by desmosomes was extensive.If the basal cell is the most important progenitor of bronchial epithelium and the cell at risk in the development of lung cancer, the presence of more basal cells in upper airways, where many lung cancers originate, may be significant. The basal cell populations in larger bronchi are perhaps the greatest concentration of cells with proliferative capability and potential for neoplastic transformation in the human bronchial tree. © 1994 Wiley‐Liss, Inc.
Meckel's cartilage in the human embryo and fetus
Authors: Orliaguet T. , Darcha C. , Déchelotte P. , Vanneuville G. 
Published: February 2005

AbstractThis work studied the development of the ventral part of Meckel's cartilage in a series of human embryos (classified in stages) and fetuses. These stages appeared particularly important: stage 16, appearance of Meckel's cartilage; stage 20, beginning of membranous ossification of mandible; and stage 23, end of the embryonic period (8th week). The primitive bony nodule which develops from the embryonic mesenchyme appears as a double bony layer forming a groove containing the neurovascular bundle, into which the dental lamina is also invaginated. It was concluded that during the fetal period, the cartilage participates in the formation of the body of the mandible in an area close to the mental foramen via endochondral ossification. The cartilage disappears in parallel with the development of ossification by the sixth month. © 1994 Wiley‐Liss, Inc.
Ultrastructural, histochemical, and morphometric analysis of skeletal muscle in a murine model of type I diabetes
Authors: Klueber Kathleen M. , Feczko John D. 
Published: February 2005

AbstractBackground. Since peripheral nerves are damaged in diabetes mellitus, morphological changes occur within the diabetic muscle in response to the diabetic neuropathy. The aim of this study was to examine the extensor digitorum longus (EDL) from a 42‐day streptozotocin‐induced diabetic Swiss Webster mouse (STZ) and compare the muscle morphology and histochemistry to age‐matched, nondiabetic controls.Methods. The EDL was evaluated using electron microscopy in order to investigate the morphological integrity of the myofibers and neuromuscular junctions. Histochemical analysis was completed using the myofibrillar CA + +‐ATPase reaction of Doriguzzi et al. (1983. Histochemistry, 79 :289–294) for use in computer‐assisted morphometric analysis of fiber size using Bioquant System 4 software.Results. Ultrastructural analysis of the diabetic EDL (N = 5, 225 myofibers/animal) showed a significant number of abnormal myofibers, exhibiting various degrees of degeneration, signs of denervation, and necrosis. The STZ myofibers exhibited excessive lipid accumulations and abnormal mitochondrial arrangements. Histochemical analysis of the STZ EDL revealed a significant shift in fiber type profile (53.6% type 2A and 46.4% type 2B‐ STZ myofibers; 47.5% type 2A, 52.5% type 2B nondiabetic controls). Morphometric analysis of myofiber size by fiber type (200 myofibers/muscle/fiber type) indicated a significant decrease in myofiber size for both type 2A and type 2B fibers in the STZ diabetic mouse.Conclusion. The degeneration and necrosis of myofibers concomitant with the sever atrophy of both the type 2A and 2B myofibers in the STZ muscle could account for the functional alterations seen in diabetic muscle. © 1994 Wiley‐Liss, Inc.
Comparative localization of carboxylesterase in F344 rat, Beagle dog, and human nasal tissue
Authors: Lewis J. L. , Nikula K. J. , Novak R. , Dahl A. R. 
Published: February 2005

AbstractBackground. Carboxylesterases (CE) exhibit high activity in the nasal mucosae and produce acid metabolites toxic to the olfactory epithelium following exposures to inhaled esters. The regional distribution and activity of CE have been studied in rodents, but no comparative studies have examined regional localization or activity in dog or human nasal tisses.Methods. We determined the immunohistochemical distributions of CE in the nasal respiratory and olfactory mucosae of Beagle dogs, and the nasal respiratory mucosa of the human nose and compared these distributions to those in the F344 rat.Results. In the dog respiratory mucosa, the greatest CE immunoreactivity was in the subepithelial glands and surface epithelial cells. In the olfactory mucosa, immunoreactivity was observed in the apical portion of the sustentacular cells, and in duct cells and acinar cells of Bowman's glands. This distribution is similar to that found in rat, except the subepithelial glands of the rat respiratory mucosa showed little to no immunoreactive CE. The human respiratory mucosa showed immunostaining in surface epithelial cells as well as glandular cells. Immunostaining in the human tissue samples was dramatically reduced in the presence of hyperplastic lesions and virtually eliminated in samples with squamous metaplasia.Conclusions. The data indicate that the distribution of CE is very similar in healthy nasal mucosae across the three species studied. However, the loss of CE immunoreactivity correlated with nasal epithelial lesions in the human samples suggests enzymatic activity may be compromised by insults to nasal tissues. Further studies of CE activity in animals following nasal insult could improve the ability to predict human responses to inhaled esters. © 1994 Wiley‐Liss, Inc.
The pulmonary neuroepithelial endocrine system in the quail, Coturnix coturnix. Light‐ and electron‐microscopical immunocytochemistry and morphology
Authors: Adriaensen Dirk , Scheuermann Dietrich W. , Gomi Toshiaki , Kimura Akihiko , Timmermans Jean‐Pierre , De Groodt‐Lasseel Marie H. A. 
Published: February 2005

AbstractDespite extensive knowledge of the neuroepithelial endocrine (NEE) system in the lungs of species of various vertebrate classes, data on avians are limited. The present investigation deals with the light‐and electron‐microscopical immunocytochemistry and morphology of pulmonary NEE cells in the quail, Coturnix coturnix. Light‐microscopically, serotonin immunoreactivity was detected in numerous solitary and clustered NEE cells located in the cilio‐mucous epithelium of primary and secondary bronchi in adult as well as in newly hatched quails. Only in newly hatched quails could a small number of bombesin‐ and somatostatin‐like immunoreactive NEE cells be demonstrated. Electron‐microscopical morphology revealed that NEE cells contained dense‐cored vesicles of a wide range of diameters and electron densities. Nearly all of the NEE cells were seen to rest on the basement membrane of the cilio‐mucous epithelium, lacking direct contact with the luminal surface. Nerve varicostities or nerve endings, of both afferent and efferent morphological appearance, were found directly apposed to the basal portion of NEE cells, invaginating between NEE cells or between NEE cells and adjacent epithelial cells. Often, synaptic specializations could be recognized between NEE cells and nerve terminals. Electron‐microscopical immunocytochemistry confirmed that the intraepithelial serotonin‐containing cells correspond to the cells with NEE characteristics. Moreover, two types of NEE cells could be distinguished in newly hatched quail lungs. Both types showed serotonin immunoreactivity selectively distributed over the dense‐cored vesicles, but somatostatin‐ and bombesin‐like immunoreactivities were only noted in one of the NEE cell types and were never seen colocalized. Thus, the avian NEE system too, harbors at least three different bioactive substances and has a morphology comparable to that of mammals, reptiles and amphibians. © 1994 Wiley‐Liss, Inc.
Gross and microscopic anatomy of the canine intrinsic cardiac nervous system
Authors: Yuan Bing‐Xiang , Ardell Jeffrey L. , Hopkins David A. , Losier Andrea M. , Armour J. Andrew 
Published: February 2005

AbstractBackground: A three‐dimensional description of the distribution and organization of the canine intrinsic cardiac nervous system was developed in order to characterize its full extent physiologically.Methods: The anatomy of the canine intrinsic cardiac nervous system was investigated in 67 mongrel dogs by means of visulization following methylene blue staining as well as by light and electron microscopic analyses.Results: Collections of ganglia associated with nerves, i.e., ganglionated plexuses, were identified in specific locations in epicardial fat and cardiac tissue. Distinct epicardial ganglionated plexuses were consistently observed in four atrial and three ventricular regions, with occasional neurons being located throughout atrial and ventricular tissues. One ganglionated plexus extended from the ventral to dorsal surfaces of the right atrium. Another ganglionated plexus, with three components, was identified in fat on the left atrial ventral surface. A ganglionated plexus was located on the mid‐dorsal surface of the two atria, extending ventrally in the interatrial septum. A fourth atrial ganglionated plexus was located at the origin of the inferior vena cava extending to the dorsal caudal surface of the two atria. On the cranial surface of the ventricles a ganglionated plexus that surrounded the aortic root was identified. This plexus extended to the right and left main coronary arteries and origins of the ventral descending and circumflex coronary arteries. Two other ventricular ganglionated plexuses were identified adjacent to the origins of the right and left marginal coronary arteries. Intrinsic cardiac ganglia ranged in size from ones comprising one or a few neurons along the course of a nerve to ones as large as 1 × 3 mm estimated to contain a few hundred neurons. Intrinsic cardiac neuronal somata varied in size and shape, up to 36% containing multiple nucleoli. Electron microscopic examination demonstrated typical autonomic neurons and satellite cells in intrinsic cardiac ganglia. Many of their axon profiles contained large numbers of clear, round, and dense‐core vesicles. Asymmetrical axodendritic synapses were common.Conclusions: The canine intrinsic cardiac nervous system contains a variety of neurons interconnected via plexuses of nerves, the distribution of which is wider than previously assumed. © 1994 Wiley‐Liss, Inc.
Immunoelectron microscopic study of the GH cell in the anterior pituitary gland of normal human fetus
Authors: Tachibana Toshiaki , Ito Takayasu , Kwon (Gotetsu Gon) Oh‐Chol 
Published: February 2005

AbstractBackground: Ultrastructural studies of growth hormoneproducing cells (GH cells) in the anterior pituitary gland have been reported using several experimental animals. However, no attempt has yet been made to identify the ultrastructural heterogeneity of the GH cells within the human anterior pituitary gland. To this end, we employed immunogold electron microscopy to investigate the ultrastructural characteristics of GH cells in relation to gestational age in normal human fetuses.Materials: Based on ultrastructural characteristics, three distinct types of GH cells were identified by immunogold electron microscopy in the anterior pituitary glands of 34 normal human fetal pituitary glands. The age of the tissue samples ranged from 8 to 34 weeks.Results: The Type‐I GH cell is a small, round cell with a narrow cytoplasm containing a few small secretory granules (268 nm in mean diameter). The GH cells designated Type‐II are polygonal and contain medium‐sized secretory granules (347 nm), profiles of rough endoplasmic reticulum (RER) arranged in parallel lamellae, and a Golgi complex which is frequently encountered but only in this cell type. The Type‐III GH cell is polygonal, large, and contains numerous large spherical‐shaped secretory granules (404 nm). The Type‐I was the predominant cell type until about 20 weeks of gestation; its incidence decreased thereafter. In contrast, the Type‐II and Type‐III cells increased in number starting at 20 weeks of gestational age.Conclusion: From these results, we suggest that Type‐I is the most immature type of GH cell, Type‐III the most mature, and the Type‐II is intermediate in development. The marked difference in the incidence of each GH cell type between the first and second half of gestation appears to be a reflection of the development of the hypothalamic regulation of the anterior pituitary gland, which is reported to be established at around 20 weeks of gestation. © 1994 Wiley‐Liss, Inc.
Comparison of osteopenic changes in cancellous bone induced by ovariectomy and/or immobilization in adult rats
Authors: Bagi C. M. , Miller S. C. 
Published: February 2005

AbstractBackground: Ovariectomy (OVX) and immobilization (IMM) in rats are useful models of osteopenia, replicating some aspects of osteoporosis in humans. The purpose of this study was to compare changes in cancellous bone after OVX and/or IMM.Methods: Differences in cancellous bone were determined at 6 and 12 weeks after OVX or IMM. Comparisons were also made when rats were ovariectomized or immobilized for 6 weeks and then immobilized (OVX/IMM) and ovariectomized (IMM/OVX), respectively, for 6 more weeks. The femurs were used to determine bone mineral content (BMC) using single photon absorptiometry (SPA) and for scanning electron microscopy (SEM). Tibias were collected for microradiography, image analysis, and histomorphometry of metaphyseal cancellous bone.Results: Six and 12 weeks after OVX, there was less cancellous bone mass, compared with controls, as indicated by SPA, SEM, microradiography, image analyses, and histomorphometry. Bone was lost primarily from the central metaphyseal regions in the OVX animals, whereas the loss occurred throughout the metaphyses in the IMM animals. There were more rodlike bone spicules and fewer platelike trabecule in the OVX and IMM groups compared with controls. Differences in the structural aspects of the cancellous bone, including differences in the types of bone struts and marrow star volumes, indicated less trabecular connectivity and greater trabecular separation in the OVX and IMM animals, compared with controls. Endochondral growth indices in the IMM groups tended to be less, whereas the OVX groups tended to be greater than controls. Cancellous bone formation rates were generally greater in the OVX groups but less in the IMM groups compared with controls. Osteoclastic resorption surfaces were substantially elevated in the IMM and OVX groups, particularly the IMM groups. Changes reflecting OVX and IMM, independently, were apparent in the OVX/IMM and IMM/OVX groups and indices of osteopenia were different from controls, including less bone mass, trabecular connectivity, and greater trabecular separation, bone turnover rates, and osteoclastic surface.Conclusions: These results demonstrate differences in the osteopenic changes that occur in cancellous bone following OVX or IMM. The changes were generally more dramatic in the IMM than in the OVX animals. When OVX and IMM were applied in combination, the osteopenic changes are particularly severe, emphasizing the importance of mechanical usage even with a deficiency of gonadal hormones. © 1994 Wiley‐Liss, Inc.
Stereological and serial section analysis of chondrocytic enlargement in the proximal tibial growth plate of the rat
Authors: Breur G. J. , Turgai J. , Vanenkevort B. A. , Farnum C. E. , Wilsman N. J. 
Published: February 2005

AbstractBackground: It has been suggested that within the growth plate, the final volume and shape of hypertrophic chondrocytes are important variables in determining the rate of longitudinal bone growth. To better understand the organization and regulation of chondrocytic hypertrophy as related to longitudinal bone growth, the beginning and end, and the location and magnitude of chondrocytic volume and shape changes during the hypertrophic process were defined in the proximal tibial growth plate of 35‐day‐old rats.Methods: In this study we used two different approaches, a stereological analysis of chondrocytes in unbiasedly defined, narrow growth plate strata, and a serial section reconstruction and measurement of individual cells. In both experiments chondrocytes were preserved using optimal chemical fixation. Proliferating chondrocytes were identified using bromodeoxyruidine labelling, and the rat of longitudinal bone growth was determined using oxytetracycline labelling.Results: In both studies, immediately following cell division in the proliferative zone, chondrocytic volume gradually increased toward the midpoint of the growth plate. During this phase of about 30 hours, approximately 20% of the final cell volume was obtained. During the following 20 hours the remaining 80% was acquired. The estimated rate of cell volume increased changed from approximately 50 μm3/hr during the first 30 hours to about 800 μm3/hr during the last 20 hours. The increase in cell volume resulted in an increase in both the vertical and the horizontal chondrocytic diameters. Cell parameters did not change during the final five hours of the maturation process.Conclusions: In this study we demonstrated that chondrocytic enlargement starts immediately following cell division in the proliferative zone, and that chondrocytic enlargement consists of two morphologically distinguishable phases. The transition point between the first and the second phase of chondrocytic enlargement corresponded with the junction between the proliferative zone and the maturation zone. © 1994 Wiley‐Liss, Inc.
Isolation of granulosal‐like cells from the bovine secretory corpus luteum and their characterization in long‐term culture
Authors: Spanel‐Borowski Katharina , Ricken Albert M. , Kress Annetrudi , Huber Peter R. 
Published: February 2005

AbstractBackground: The isolation of cells termed type 5 from the bovine corpus luteum was recently reported. Since these cells were reminiscent of immature granulosa cells, their morphological and functional relationship requires further investigation in view of the novel concept of corpus luteum growth. It suggests that putative stem cells of unknown origin supply the pool of small luteal cells.Methods: Bovine corpora lutea were mechanically dispersed, cell suspensions separated over a Percoll® density gradient, and type 5 cells purified by colony transfer. Granulosa cells were harvested from small‐sized antral follicles. Observations were carried out at the light and electron microscopical level. 3β‐Hydroxy‐steroid‐dehydrogenase was localized histochemically in addition to intracellular lipid droplets stained with nile red. Immunolocalization was used to study Factor VIII antigen presence, the architecture of the cytoskeleton, as well as the occurrence of neuronal cell adhesion molecules, and of neuronal cadherin‐like molecules. The uptake of acetylated low density lipoprotein was examined. As for progesterone concentration, cells were seeded at low density on day zero. Cell numbers and progesterone levels of supernatants were determined on day 10 in culture.Results and Conclusions: Type 5 cells behaved morphologically like immature granulosa cells, yet the total cell number and the progesterone concentration differed for type 5 cells compared to granulosa cells. The addition of LH had no influence on the progesterone concentration as seen for either type 5 cells or for granulosa cells. It is concluded that type 5 cells, which were originally mistaken for microvascular endothelial cells, display similarities with immature granulosa cells. Type 5 cells may play a role in renewal of luteal cells. © 1994 Wiley‐Liss, Inc.
Morphological and histochemical study of human submucosal laryngeal glands
Authors: Pastor Luis M. , Ferran Antonio , Calvo Alfonso , Sprekelsen Carlos , Horn Ramon , Marin Juan A. 
Published: February 2005

AbstractBackground: The respiratory submucosal glands are a major source of secretions in the airway. Human submucosal laryngeal glands have been scarcely studied, with no works existing about their ultrastructure and histochemistry.Methods: Samples of epiglottis, ventricle, false vocal folds and true vocal folds were fixed in 10% buffered formalin for histochemical study with conventional and carbohydrate lectin histochemistry. Other samples were fixed in 2.5% glutaraldehyde and conventionally processed for transmission electron microscopy.Results: The human submucosal laryngeal glands are composed of serous tubules; mucous tubules; collector duct; and final portion of this duct. The serous cells showed sialosulphomucins and affinity for WGA and Con‐A lectins. With a previous treatment with neuraminidase, they also labelled with PNA. The mucous cells contained sialosulphomucins and showed affinity for WGA and DBA lectins in the samples proceeding from blood group A, and for WGA, UEA‐I and LTA with those from blood group O. Ultrastructurally, the serous cells presented a wide variety of granules, cells in which seromucous granules predominated. The mucous cells presented larger‐sized granules which were very electron‐lucent. The collector duct was composed of mitochondria‐rich cells and basal cells. A cell which we have termed “intermediate” was identified in the transition zone between the mucous tubules and the collector duct, and in the final portion of the collector duct. It had morphological characteristics as if it were a transition between a goblet cell and collector duct cell. Some nerve endings with cholinergic and peptidergic vesicles were found among the myoepithelial cells.Conclusions: These glands presented some histological differences from the bronchial glands, the mucous secretion was related to the blood group antigens, and the serous cells showed a wide variability in their secretory granules, many of them being of a seromucous type. © 1994 Wiley‐Liss, Inc.