bluuebunny/crossref_metadata_2025_split huggingface dataset:
Autoradiographic location of sensory nerve endings in dentin of monkey teeth
Authors: Byers Margaret R. , Dong Willie K. 
Published: February 2005

AbstractWe have used the autoradiographic method to locate trigeminal nerve endings in monkey teeth. The nerve endings were labeled in two adult female Macaca fascicularis by 20 hours of axonal transport of radioactive protein (3H‐L‐proline). We found a few labeled axons in contralateral mandibular central incisors and one mandibular canine. In ipsilateral teeth, numerous myelinated and unmyelinated axons were labeled; they formed a few terminal branches in the roots but primarily branched in the crown to form the peripheral plexus of Raschkow and to terminate as free endings in the odontoblast layer, predentin, and as far as 120 μm into dentinal tubules. Electron microscopic autoradiography showed that the radioactive axonally transported protein was confined to sensory axons and endings; odontoblasts and dentin matrix were not significantly labeled. Labeled free nerve endings were closely apposed to odontoblasts in dentin but did not form distinctive junctions with them.Nerve endings were most numerous in the regular tubular dentin of the crown adjacent to the tip of the pulp horn, occurring in at least half of the dentinal tubules there. Reparative dentin was poorly innervated, even near the tip of the crown, and it had a different tubular structure and adjacent pulpal structure from the innervated dentin. Radicular dentin was not innervated in most areas but did contain a few labeled axons where the predentin was wide and the odontoblasts were columnar, as at the buccal and lingual poles of some roots.Our results show that dentinal sensory nerve endings in primate teeth can be profuse, sparse, or absent depending on the location and structure of dentin and its adjacent pulp. When dentin was innervated, the tubules were straight and contained odontoblast processes, the predentin was wide, the odontoblast cell bodies were relatively columnar, and there was an adjacent cell‐free zone and pulpal nerve plexus.
Silver methods applied to semithin sections to identify peptide‐producing endocrine cells
Authors: López J. , De Rada O. Díaz , Sesma P. , Vázquez J. J. 
Published: February 2005

AbstractSilver methods were successfully applied to semithin sections of Epon‐embedded material, in bronchial epithelium of the chicken lung, as well as in stomach and gut of the frog. Silver methods with some modifications characterize very well the cytoplasmic argyrophilic and argentaffin granules. They give good results in plastic‐embedded material.
A new look at the mineralized and unmineralized components of intraosseous fibers of the interdental bone of the mouse
Authors: Johnson Roger B. 
Published: February 2005

AbstractThe degree of mineralization of deeply embedded intraosseous fibers has been the subject of speculation. However, there were few available descriptive morphological studies addressing this question. The present study demonstrated that morphological differences were evident between intraoseous fibers of different levels of the interdental septum. It also revealed that the degree of mineralization of intraosseous fibers was often different at the wall of the tooth socket in comparsion to that at deeper levels of interdental bone. Except in the superior crestal third, intraosseous fibers became less mineralized as they passed from the wall of the tooth socket to the midline of the interdental septum. They were surrounded by sheaths throughout their distribution. It was concluded that there might be significant differences in the morphology of intraossoeus fibers of the mouse in comparision to the morphology of intrasseous fibers of the dog, which have previously been described in detail.
A granular cell at the acinar‐intercalated duct junction of the rat submandibular gland
Authors: Qwarnström E. E. , Hand A. R. 
Published: February 2005

AbstractA granular cell was present at the acinar‐intercalated duct junction in submandibular gland of adult rats of several different strains. It occurred more frequently in females thanin males. It was a small pyramidalshaped cell, usually forming the most proximal part of the intralobular duct system. The cell contained a relatively large, basally located nucleus. Numerous heterogeneous granules, usually exhibiting both electron‐dense and electron‐lucent regions, were present in the apical cytoplasm. Exocytosis of the granules at the apical cell surface was occasionally seen. Dilated cisternae of endoplasmic reticulum were frequently observed between the apical granules and in the basal and lateral cytoplasm. The function of the granular cell is unknown. Their structure and location suggest that they may (1) constitute a mature secretory cell population, or (2) represent progenitor cells for acinar and/or intercalated duct cells.
Ultrastructural and biochemical changes in rat soleus muscle following tenotomy
Authors: Margolis Ronald N. , Baker James H. 
Published: February 2005

AbstractThis study was designed to correlate changes in the ratelimiting enzymes of glycogen synthesis (glycogen synthase) and glycogen breakdown (glycogen phosphorylase) with the ultrastructural changes which occur in the soleus muscle following tenotomy. Soleus muscles were removed at 1, 2, 3, 7, 14, 21, and 63 days after tenotomy and were prepared for electron microscopy or frozen for enzyme analysis. In the first 7 days posttenotomy, soleus muscle fibers underwent a series of degenerative changes, while both synthase and phosphorylase activities decreased. Over the next 8 weeks the histological appearance of the soleus muscle eventually returned to normal while synthase and phosphorylase activities increased. We suggest that recovery from tenotomy involves an increase in the energy demands of the muscle, resulting in the increased activity of the key rate‐limiting enzymes of muscle glycogen metabolism from the drastically reduced levels observed in the period before recovery begins.
Effect of ethanol on nucleolar structure: A cytological indication of change in RNA/protein synthesis
Authors: Dunmire Carole R. , Lavelle Faith W. 
Published: February 2005

AbstractThe effects of chronic ethanol ingestion on an organelle known to be involved in protein synthesis were studied cytologically in nerve cells of the adult hamster. Twenty‐six animals were administered standard laboratory chow and either tap water (controls) or a 15% ethanol solution (experimentals) for a period of 7 weeks. Brains were perfusion‐fixed, sectioned transversely, and stained with buffered thionin for microscopic analysis. Reported here are changes in an RNA‐rich intranucleolar body (INB) seen in facial motor neurons and cerebellar Purkinje cells of the golden hamster. After chronic ethanol ingestion, the size and frequency of the INB increased significantly in both cell populations. Theoretical considerations are discussed concerning the correlation between this apparent storing of nucleolar RNA/RNP and the biochemical evidence of other investigators for ethanol‐induced alterations in RNA/protein synthesis and utilization in neurons.
The liver hemopoietic environment: I. Developing hepatocytes and their role in fetal hemopoiesis
Authors: Medlock Eugene S. , Haar Jack L. 
Published: February 2005

AbstractMouse fetal liver was studied ultrastructurally to identify and charaterize the developing hepatic parenchyma or prehepatocyte which may be responsible for producing the liver hemopoietic enviroment. It was observed that as the liver develops, there is close association of endodermal and mesenchymal cells in the region of the septum transversum. Numerous intercellular adhesions were observed between endodermal cells and mesenchymal cells. Twenty‐fours after endodermal and mesenchymal cells first intermingle, the liver extravascular space consisted of consisted of spherical hemopoietic cells dispersed among a heterogenous population of dark and light cells. The reticulum of prehepatocytes formed a three‐demensional cellular network which structurally supported the hemopoietic cells residing in the liver. By 12 days of gestation, prehepatocytes were a homogenous population of dark, stellate cells joined together by numerous intercellular adhesions. Broad areas of intercellular association were noted between processes and prehepatocytes and hemopoietic cells; however, no inercellular junctions between these two disparate cell populations were observed at this or any stage in development. Characteristics reflecting a cell population capable of synthesis and secretion of proteinaceous substances, namely, dilated Golgi apparati, increased numbers of polyribsomes and profiles of rough endoplasmic reticulum (RER), two types of vacuoles and/or vesicles, and intercellular microvillus‐lined spaces, were observed in the prehepatocytes between 12 and 17 days gestation. By day 17 of gestation, glycogen accumulation, biliary channel development, appearance of a subendothelial microvillus surface, nuclear shape and chromatin pattern, and arrangement of cytoplasmic organelles reflected the maturation of prehepatocytes into hepatocytes, the adult liver parenchyma.
A quantitative study of muscle spindles and tendon organs in some intrinsic muscles of the hand in the bonnet monkey (Macaca radiata)
Authors: Devanandan M. S. , Ghosh S. , John K. T. 
Published: February 2005

AbstractThe number and density of muscle spindles and tendon organs have been determined in the following intrinsic muscles of the hand of bonnet monkeys: I lumbrical, II lumbrical, abductor digiti minimi, adductor pollicis, and I dorsal interosseous. All these muscles were found to be very rich in muscle spindles (17.6 to 42.31 per gram wet weight) but relatively poor in tendon organs (0.606 to 10.06 per gram wet weight). The lumbricals have very few tendon organs. The possible functional significance of these findings has been discussed.
Effect of castration and testosterone replacement on high glucose 6‐phosphatase activity in principal cells of the mouse epididymis
Authors: Kanai Kazuo , Kanamura Shinsuke , Watanabe Jun , Asada‐Kubota Mari , Yoshikawa Motoko 
Published: February 2005

AbstractGlucose 6‐phosphatase activity is higher in the principal cell than in other cell types in the terminal segment and caudal half of the middle segment of the mouse epididymis. Effect of castration and testosterone replacement on the high enzyme activity in the principal cell was studied in the terminal segment and the caudal half of the middle segment (cytochemical study), and in the whole epididymis (biochemical study). Ten, 20, or 30 days after castration, the abundant amount of reaction product seen in principal cells from intact control animals decreased to the level in basal cells, halo cells, and smooth muscle cells. However, in animals treated with testosterone following castration, the reaction product in principal cells remained abundant. Changes in the biochemical activity after castration or testosterone administration following castration paralledled the cytochemical results. Thus, the high activity in the principal cell is under the control of testosterone.
Intermediate filaments of the cytoskeleton in glandular cells of the rat fundic mucosa: Immunofluorescence and electron microscopy study
Authors: Dabiké Mónica , Koenig Cecilia S. 
Published: February 2005

AbstractThe organization of intermediate filaments (IF) in cells of the rat fundic mucosa was studied by electron microscopy and immunofluorescence microscopy using specific antiprekeratin antibodies on frozen sections and isolated cells.Our results suggest that mucous cells lining the gastric surface and the gastric pits, which appeared strongly decorated, are the most rich in IF. These cells displayed coarse bundles of IF oriented in all directions as well as desmosome‐attached tonofibrils. Mucous neck cells contained fewer bundles of IF located preferentially toward the apical region. Zymogen cells showed a strong staining along the contour of the luminal border, together with a faint decoration of a fine meshwork extending throughout the cytoplasm. A poorly defined fibrillar cortex present underneath the secretory plasma membrane and sparse bundles of IF among the elements of the rough endoplasmic reticulum were seen in thin sections. In contrast, parietal cells appeareed brightly stained and the prekeratinlike material formed a cortical polygonal meshwork especially visible in isolated cells. A developed system of IF formed by conspicuous bundles located underneath the secretory canaliculi, among the mitochondria and in the vicinity of the basal plasma membrane, was observed in the electron microscope.
Two anatomical pathways for the renewal of surface glycoproteins in chloride cells of fish gills
Authors: Pisam M. , Chrétien M. , Rambourg A. , Clermont Y. 
Published: February 2005

AbstractThe cytoplasm of chloride cells found in the epithelium lining the gills of guppies (Lebistes reticulatus) contains, in addition to the Golgi apparatus and cisternae of endoplasmic reticulum, two distinct membranous components, the vesiculotubular and the tubular systems. While the latter is connected to the laterobasal plasma membrane, the former, made up of small vesicles and short membranous tubules, is seen mainly between the Golgi apparatus and the apical cavity which invaginates the apex of the cell. The role of these two systems in the transport of glycoproteins from the Golgi apparatus to the cell surface was investigated in fishes maintained in fresh and salt water, injected with 3H‐fucose, and sacrificed at various intervals thereafter (10 and 30 min; 2.5, 8, 15.5, 24, and 48 hours). The distribution of the label was analyzed by quantitative radioautography in sections examined with the light and electron microscopes. The light microscopic data suggested that the label incorporated in the supranuclear region, where the Golgi apparatus is located, migrated toward the apical and the laterobasal regions of the chloride cells. The relative concentration of the tracer over the various components of the cytoplasm of these cells was calculated from data collected on electron microscope radioautographs at various intervals after 3H‐fucose injection. The curves obtained supported the view that glycoproteins synthesized in the Golgi apparatus were transported to the apical surface via the vesiculotubular system, and to the laterobasal membrane via the tubular system.
The permeability of human amniotic epithelium: Studies using lanthanum as a tracer
Authors: King Barry F. 
Published: February 2005

AbstractTo study the permeability of human amniotic epithelium to small molecular weight substances, pieces of nonplacental amnion, with attached chorion laeve and decidua, were exposed to solutions containing lanthanum salts and processed for electron microscopy. Lanthanum penetrated the intercellular spaces and often reached the basal lamina region. In addition, some lanthanum was bound to the glycocalyx of the microvilli on the apical surfaces of the cells. Little lanthanum was found deep to the basal lamina. The results suggest the intercellular pathway is of major importance in the movement of small molecules across amniotic epithelium.
Scanning electron microscopic structure of the finger print as related to the dermal surface
Authors: Misumi Yuko , Akiyoshi Toshio 
Published: February 2005

AbstractThis paper aims to clarify the relationship of the dermis to epidermal ridge configuration. After fixation, human fingertip epidermis was peeled off from the dermis by alkaline treatment, and the dermal surface was observed with the scanning electron microscope (SEM). The SEM pattern of furrows, grooves, and papillae showed an exact negative fingerprint image. Papillae had various sizes and complicated shapes and were arranged continuously but irregularly on each side of the furrow. Size and shape variabilities were not dependent on the site of the fingerprint region. The papilla number tended to increase with age due to derivation of secondary papillae from the primary papilla as well as new formation of small papillae. The dermal surface exhibited some site‐specific fibrous appearance at the furrow and papilla, whereas the surface was smooth at the groove. The characteristics of the dermal surface structure as related to the epidermis can be explained by a stronger dermis‐epidermis adhesion at the furrow than at the papilla or at the groove.
Ontogeny of immunoreactive somatostatin in thyroid C cells from dogs and guinea pigs
Authors: Kameda Yoko , Oyama Hideki , Horino Masaharu 
Published: February 2005

AbstractThe development of immunoreactive somatostatin in thyroid C cells of dogs and guinea pigs from early fetuses to adults was investigated by the use of immunoperoxidase histochemistry and radioimmunoassay. The time of appearance and developmental patterns of immunoreactive somatostatin in the C cells were completely different in both species. In guinea pig thyroids, the somatostatin immunoreactivity appeared later than the calcitonin immunoreactivity and the number of somatostatin‐positive cells was very small during fetal periods. The somatostatin immunoreactivity rapidly increased during neonatal periods. A large population of the somatostatin cells and a high concentration of somatostatin immunoreactivity were observed in mature animals. On the other hand, in dog fetuses somatostatin immunoreactivity appeared very early, at the same time as the calcitonin immunoreactivity. The largest population of somatostatin cells was found at the stage when the primordial follicles were vigorously formed throughout whole thyroid parenchyma. At this stage almost all of calcitonin‐positive cells were also somatostatin‐positive. The somatostatin cells progressively decreased as the development proceeded, in contrast to the calcitonin cells which increased with gestational age. In postnatal dogs only a few C cells revealed the immunoreaction for somatostatin, and the concentration of somatostatin was very low. These findings suggest that the function of somatostatin in dog thyroid C cells may be different from that in guinea pig C cells.
Myosatellite cells, growth, and regeneration in murine dystrophic muscle: A quantitative study
Authors: Ontell Marcia , Feng K. C. , Klueber Kathleen , Dunn Robert F. , Taylor Floyd 
Published: February 2005

AbstractPatterns of growth and regeneration in 2‐, 4‐, 8‐, and 17‐week‐old murine dystrophic (129 ReJ dy/dy) extensor digitorum longus muscles have been determined. Necrosis and myofiber loss, hypertrophy, and regeneration result in a reduced population of myofibers whose diameter distribution is more extensive than that found in the extensor digitorum longus muscles of age‐matched normal mice. At the onset of dystrophic symptoms (2 weeks postnatal), the ratio of myosatellite cell nuclei to the total sublaminal nuclear population (myonuclei + myosatellite cells) is similar to that found in 2‐week‐old control muscles. The frequency of finding myosatellite cells decreases with age in both control and dystrophic muscles. Myosatellite cells account for 11%, 6%, 5%, and 3% of the total sublaminal nuclear population in control muscle and 12%, 8%, 6%, and 5% of the total sublaminal nuclear population in dystrophic muscle at 2, 4, 8, and 17 weeks, respectively. No preferential association of myosatellite cells with myofibers of a particular diameter is found in control muscle or in the two youngest dystrophic groups. At 8 and 17 weeks, myosatellite cells are less frequently encountered on small‐diameter, regenerating myofibers of dystrophic muscle, and they are preferentially associated with large diameter, hypertrophied myofibers. The labeling index of myosatellite cells decreases with age in both normal and dystrophic muscle. At all ages the myosatellite cell labeling index is higher in dystrophic muscle (23%, 7%, 5%, and 2% at 2, 4, 8, and 17 weeks, respectively) than in normal muscle (5%, < 1% at 2 and 4 weeks, respectively), with no labeled myosatellite cells being found in 8‐ and 17‐week‐old normal muscles. It is suggested that the magnitude of the regenerative response of dystrophic murine muscle decreases with age and that this factor may be responsible for the inability of the regenerative response of dystrophic muscle to keep pace with the rapid muscle deterioration.
Ultrastructure of the secretory epithelium, nerve fibers, and capillaries in the mouse sweat gland
Authors: Quick Donal C. , Kennedy William R. , Yoon Kwon S. 
Published: February 2005

AbstractThe ultrastructure of the mouse sweat gland was examined, in support of neurological studies of sweat glands and their relationships to the autonomic nervous system. It was found that the mouse sweat gland is similar to that of the rat and has only one type of secretory cell. Many nerve fibers are entwined with the secretory tubule and contain accumulations of round, clear vesicles, some microtubules, but apparently no neurofilaments. Cholinesterase is found in the clefts between nerve fibers and their ensheathing Schwann cells. The nerve fibers tend to run parallel with capillaries, but have no close association with either the capillaries or the secretory epithelium. Capillaries provide an abundant blood supply to the sweat gland and are fenestrated. The relationships between cellular elements of the sweat gland provide no direct evidence of the mechanisms involved in neurogenic sweating, although it seems likely that effector substances are diffusely distributed.
A comparison of the density of microtubules in the central and peripheral axonal branches of the pseudounipolar neurons of lizard spinal ganglia
Authors: Pannese E. , Ledda M. , Arcidiacono G. , Rigamonti L. , Procacci P. 
Published: February 2005

AbstractThe number and density of microtubules were determined in cross sections of the two branches (central and peripheral) of the bifurcating axon of the pseudounipolar neurons of the lizard thoracic spinal ganglia. In both the central and peripheral branches the average number of microtubules rose, while the microtubular density decreased with an increase in the cross‐sectional area of the axonal branch: More precisely, a linear relationship was observed between the logarithm of the microtubular density and the cross‐sectional area of the axonal branch. Both the average number of microtubules per cross section of the axonal branch and the microtubular density were found to be significantly lower in the central than in the peripheral branch. Since the amount of material carried by fast transport was found by other authors to be greater in the peripheral than in the central branch, a positive correlation seems to exist between microtubular density and the quantity of material carried by fast transport along the two branches of the axon in pseudounipolar neurons. Such a correlation suggests that microtubules may be somehow involved in the fast transport of material along the axon.The average densities of microtubules were found to be the same comparing two sets of unmyelinated and myelinated central (or peripheral) branches of corresponding size. Therefore, different microtubular densities usually observed in unmyelinated and myelinated axons appear to be correlated with the different size ranges of the two types of axon rather than with the absence or presence of the myelin sheath.