bluuebunny/crossref_metadata_2025_split huggingface dataset:
The cellular organization of fibroblastic cells and macrophages at regions of uncalcified cartilage resorption in the embryonic chick femur as revealed by alkaline acid phosphatase histochemistry
Authors: Sorrell J. Michael , Weiss Leon 
Published: February 2005

AbstractResorption of uncalcified cartilage in the embryonic chick femur appears to be mediated by two types of mononuclear cells. One cell type lies flattened and adherent along the surface of the cartilage matrix into which it extends cellular processes. Cytological characteristics of a large, euchromatic nucleus containing a nucleolus, and cytoplasm containing moderate to extensive amounts of rough endoplasmic reticulum indicate that these are protein synthetic cells. Macrophages, characterized by a pleomorphic shape and cytoplasm containing numerous mitochondria and vesicles, comprise the second cell type. These may be seen lying in contact with cartilage matrix, but are more likely located in the nonhematopoietic marrow adjacent to resorbing cartilage, where they establish close cellular associations with protein synthetic cells.Alkaline and acid phosphatase histochemical studies differentiate these two cellular types. Marrow alkaline phosphatase activity is restricted to the cartilagemarrow interface from which it diffuses a short distance into cartilage matrix, but does not diffuse into nearby marrow. Intracellular alkaline phosphatase is present only in protein synthetic cells that line the surface of cartilage, and thus appears to be produced by these cells. Acid phosphatase positive macrophages are scattered throughout the marrow, but are found in greatest concentrations in the region of cartilage resorption. They are rarely in direct contact with cartilage, and there is no evidence that acid phosphatase is released from these cells. The relative localizations and the presence of cellular interactions of these two cell types suggests that protein synthetic cells may be of fibroblastic origin, and may play a primary role in cartilage degradation, while macrophages, in keeping with biochemical evidence, play an adjunct or possibly a regulative role.
Direct correlation of histochemical profile to the ultrastructure of single myofibers and their neuromuscular junctions from a mixed muscle
Authors: Galvas Patrick E. , Neaves William B. , Gonyea William J. 
Published: February 2005

AbstractIt has been demonstrated that there are significant differences in the ultrastructural morphology of the three mammalian myofiber types and their neuromuscular junctions (NMJ). The description of these ultrastructural differences was based primarily on samples taken from muscles that were composed of predominantly one fiber type. The objectives of this study were 1) to determine if previously described ultrastructural characteristics could distinguish between the three fiber types and the NMJ in a mixed muscle containing similar percentages of each fiber type and 2) to determine if there were significant differences in the morphology of like fiber types when compared between two histochemical regions in a muscle with a compartmentalized fiber‐type distribution. The muscle used in this study was the flexor carpi radialis (FCR) of the cat. The objectives were achieved by a direct correlation of ultrastructure to histochemical profile on the same isolated myofibers. This study revealed a wide range of morpohological variation among fiber types in the FCR. Although many fibers from the FCR could be classified by using accepted ultrastructural criteria, most could not. Compartmental differences were present in several of the ultrastructural parameters measured. The slow‐twitch oxidative (SO) and fast‐twitch oxidative‐glycolytic (FOG) fibers in the oxidative compartment had a significantly larger myofiber core volume when compared to the fast‐twitch glycolytic (FG) fibers from both compartments. Also, the FG fibers in the glycolytic region had a significantly larger membrane volume (terminal cisternae, T tubules, and sarcoplasmic reticulum) when compared to the FOG fibers in the oxidative compartment and the SO fibers in both regions.This study has demonstrated that considerable variation exists in the most commonly accepted ultrastructural features used for distinguishing the three myofiber types when sampled from a mixed muscle that is not dominated by one fiber type. These results suggest the possibility of a greater functional range in the same type of histochemically identified motor units from mixed muscle than in those from muscles containing predominantly one fiber type.
Coronary artery distribution in bonnet monkeys (Macaca radiata)
Authors: Buss Daryl D. , Hyde Dallas M. , Poulos Paul W. 
Published: February 2005

AbstractFull use of nonhuman primates as a model for coronary vascular disease has been hampered by several factors, including the limited availability of detailed coronary anatomic data. This study was undertaken to identify the gross coronary arterial anatomy of the Bonnet monkey (Macaca radiata). The hearts of sixteen adult male Bonnet monkeys were subjected to postmortem coronary angiography and gross morphological examination. The main left coronary artery divided into the left anterior descending coronary artery (LAD) and the left circumflex coronary artery (LCA). The posterior descending coronary artery (PDCA) arose from the LCA in 31% of the cases and from the right coronary artery (RCA) in 56% of the hearts. Hearts from two animals (13%) had paired arteries, arising from the LCA and RCA, located in the posterior interventricular groove. The arterial supply to the sinoatrial node originated from the LCA in 69% of the animals and from the RCA in the remainder. The atrioventricular node was supplied by a branch of the RCA in 69% of the animals and from the LCA in the remainder. The coronary anatomy of the bonnet monkey resembles that of man more closely than does the dog in terms of origin of the PDCA, supply of the sinoatrial and atrioventricular nodes, and perfusion of the interventricular septum. The Bonnet monkey may therefore be a useful model for certain specific pathophysiological studies on the coronary circulation.
Cellular distribution within the rat adenohypophysis: A morphometric study
Authors: Poole Max C. , Kornegay W. Daniel 
Published: February 2005

AbstractA morphometric analysis of the cell types within the adenohypophysis of the female rat was conducted with an emphasis on regional variations. Type I and type II gonadotropes and corticotropes had the largest volumes, mammotropes and somatotropes were of medium size, and thyrotropes and chromophobes were the smallest cells. There was no regional variation in the volumes of the respective cell types.Somatotropes and mammotropes were most numerous, followed by the gonadotropes, chromophobes, corticotropes, and thyrotropes. There was no significant regional localization of the somatotropes, mammotropes, corticotropes, and thyrotropes. Gonadotropes were best defined as two populations with type I cells being localized in the central regions and type II cells being distributed throughout the gland. Chromophobes were the only cells with a significant distribution in the anterior regions and were most numerous in the anterior peripheral regions. These fine‐structural morphometric findings are discussed in relation to other studies of the adenohypophysis that utilize immunocytochemistry.
Immunohistochemical study of C cell follicles in dog thyroid glands
Authors: Kameda Yoko 
Published: February 2005

AbstractIn dog thyroid glands there are C cell follicles which are lined solely by C cells and which accumulate a colloidlike substance in the luminal cavities. In order to clarify the properties of the colloidlike substance secreted by C cells, the C cell follicles were stained with PAS reaction and immunoperoxidase method using anticalcitonin, anti‐C‐thyroglobulin, and anti‐19S‐thyroglobulin antisera, respectively. The colloidlike substance was PAS positive and revealed the strong immunoreaction for C‐thyroglobulin but a faint reaction for calcitonin. It was nonreactive with anti‐19‐thyroglobulin antiserum. These results confirm that C cells synthesize the glycoprotein immunoreactive to anti‐C‐thyroglobulin antiserum in addition to calcitonin and can store it in the follicular lumens.
Anionic sites on the surface of frog ependymal astrocytes and mouse ependymal cells
Authors: Korte Gary E. , Rosenbluth Jack 
Published: February 2005

AbstractThe binding of colloidal iron hydroxide (CI) and ruthenium red (RR) to the plasma membrane of frog ependymal astrocytes was examined by electron microscopy. Positively charged CI and RR bind to the external surface of the plasma membrane of all parts of the ependymal astrocyte. Prior treatment with neuraminidase markedly reduces the number of bound CI particles, suggesting that the sialic acid of carbohydrates associated with the cell surface is responsible for much of the CI binding. Comparable observations were made on mouse ependymal cells. These findings indicate that an anionic, carbohydrate‐rich cell coat occurs on the plasma membrane of amphibian ependymal astrocytes and mammalian ependymal cells. This cell coat may be related to transport, barrier, or receptive functions of ependymal cells.
Histochemical localization of prostaglandin synthetase in human exocrine glands
Authors: Sirigu Paola , Cossu Margherita , Perra Maria Teresa 
Published: February 2005

AbstractProstaglandin synthetase activity is histochemically detected in the epithelial cells of the human prostate, seminal vesicle, and deferential ampulla. The addition of the specific inhibitor indomethacin to the incubating medium strongly reduces the staining reaction. The presence of exogenous substrate in the medium is not required for the reaction, since identical results are observed following incubation with and without arachidonic acid. The presence of the enzyme appears to be related to the secretion of prostaglandins into the seminal fluid, but there is a possibility that some prostaglandins influence the metabolism of the secreting cells themselves. The localization of prostaglandin synthetase in the ductal epithelia of human salivary glands is related to a possible regulatory role of the prostaglandins upon the reabsorptive activity of the ductal cells.
Histomorphometry and autoradiography of cultured fetal rat long bones
Authors: Nefussi Jean‐Raphael , Vignery Agnes , Puzas J. Edward , Baron Roland 
Published: February 2005

AbstractThe behavior of fetal rat long bones cultured in vitro according to Raisz's technique (1969) was studied by histomorphometry and autoradiography for a period of four days. The changes were recorded daily both on the trabecular and cortical bone by measuring the bone volume, the number of osteoclasts, and the number of nuclei per osteoclast. Radioactive calcium release was measured and compared to the changes in bone volume and in the number of osteoclasts. An autoradiographic study, using 3H‐proline and 3H‐thymidine in flash labeling in the medium and 3H‐thymidine in follow‐up labeling after one injection in vivo was performed to evaluate the bone formation, the cellular proliferation rate and cell differentiation. After four days in culture, an increase in total calcified bone volume was observed which correlatd with changes in the trabecular bone. No significant changes were recorded in the cortical bone. The results showed a good maintenance of the resorption and formation phenomena through an active process of cellular multiplication and differentiation. Undifferentiated cells were labeled in flash label and osteoblast, osteocyte and some osteoclast nuclei were labeled in follow‐up studies.
Intralitter variation of neonatal rat lung morphology following prenatal maternal hypervitaminosis A
Authors: Newman L. M. , Johnson E. M. , Cadogan A. S. A. 
Published: February 2005

AbstractPrenatal exposure to excess vitamin A (160,000 USP units/day) from days 15 through 19 of gestation results in altered lung morphology, characterized by thickened septal walls and/or large areas of atelectasis and an associated high neonatal mortality. Marked variability in both morphological and physiological expression from this prenatal insult is commonly seen between litters and littermates, making analyses difficult. The present study documents morphological intralitter variation observed in vitamin A‐exposed 2‐day‐old rats as compared to controls. Representative midhilar coronal histological sections of each lung were examined by two methods and the results compared. The first method, although less sensitive, demonstrated that five out of eight experimental rat lungs had a significantly greater percentage of tissue to airway space as compared with undisturbed controls (>43%). The second method, using several morphological criteria and a grid system to score parenchyma into classifications based on the degree of morphological variation and projected functional capability, clearly found significantly increased percentages of poor or nonfunctional lung tissue (P < 0.01) in seven out of eight pups exposed to excess vitamin A. This method of ranking the severity of adverse effects on tissue morphology allowed identification of drug‐affected newborn and provided a means to quantify the alterations. Such a means for identifying affected individuals from littermates is essential to research methodologies for detecting substances which, when administered during fetal life, produce decrements of postnatal function but no gross structural abnormalities.
Somatostatin immunoreactive C cells in thyroid glands from various mammalia species
Authors: Kameda Yoko , Oyama Hideki , Endoh Masahiko , Horino Masaharu 
Published: February 2005

AbstractThe relative distribution of somatostatin‐ and calcitonin‐containing cells in thyroid glands from various mammalian species was investigated by immunoperoxidase staining, and the concentration of immunoreactive somatostatin by radioimmunoassay. In the thyroid glands of guinea pigs and rabbits, most of the calcitonin cells were also immunoreactive to the somatostatin antiserum, and high concentration of immunoreactive somatostatin was obtained. On the other hand, in the thyroids of other animal species—rats, dogs, pigs, cows, goats, cats, monkeys, mice, and hamsters—only a few C cells revealed the immunoreaction for somatostatin, and the concentration of somatostatin was low. In all animal species studied, the somatostatin was present in the same cells that contain calcitonin, though in guinea pigs and rats there were some C cells containing a large number of reaction products for somatostatin but very few for calcitonin. Thus, it was concluded that there was a considerable variation in somatostatin immunoreactivity of thyroid C cells from species to species.
A description of the times of appearance and regression of marginal lingual papillae in human fetuses and newborns
Authors: Yamasaki Fusao , Takahashi Kyozo 
Published: February 2005

AbstractPapillae, located along the anterolateral margin of the human tongue, were observed in fetal and newborn stages. The papillae appeared in the prenatal period and attained maximum development in the newborn. They had almost disappeared by the time of weaning. Although morphologically, the papillae may be considered to be a form of the filiform papillae, they differed from the filiform papillae in that they were temporary, localized at the anterolateral margin of the tongue, and larger in size. These papillae are homologous with those in certain land mammals and toothed whales, and may assist in sucking. Our findings on the times of appearance and regression of marginal papillae support this notion.
Carbonic anhydrase histochemistry in rabbit and mouse kidneys
Authors: Dobyan Dennis C. , Magill Linda S. , Friedman Peter A. , Hebert Steven C. , Bulger Ruth Ellen 
Published: February 2005

AbstractThe presence of carbonic anhydrase activity in rabbit and mouse kidneys was examined using a histochemical procedure with plastic embedded sections stained by the modified version of the cobalt‐phosphate method (Hansson, 1967, 1968; Ridderstrale, 1976). Proximal convoluted tubules (S1 and S2 segments) in both species were strongly positive for carbonic anhydrase activity on the membranes of the luminal, lateral, and basal surfaces. The apical cytoplasm beneath the brush border and the nuclei also stained positively for carbonic anhydrase. The S3 segment (pars recta) of the proximal tubule in the rabbit was positive on the luminal membrane, with somewhat less intensity seen on the lateral and basal surfaces. This segment in the mouse was completely negative. The first part of the thin limbs of long‐looped nephrons exhibited strong staining in the mouse. Faint luminal staining was present on descending thin limbs of short‐looped nephrons in the mouse. In the rabbit, both the medullary and cortical ascending thick segments of the limb of Henle were completely negative. In contrast, the medullary and cortical ascending thick limbs in the mouse kidney showed staining on all plasma membranes. The intercalated cells in the cortical and medullary portion of the collecting tubules stained positively for carbonic anhydrase in both species. The principal cells of the collecting duct in the cortex were negative in the rabbit and faintly positive in the mouse. The principal cells in the upper medullary collecting tubules in both species stained intensely along the luminal, lateral, and basal cell membranes. The papillary collecting ducts were largely negative in both the rabbit and the mouse. Some interstitial cells in the rabbit in the region of the papillary tip were strongly positive. We conclude that there is a marked difference in carbonic anhydrase activity within and between the renal tubular segments of the rabbit and the mouse. In addition, these distinct differences that exist between the two species correlated with known physiological roles in ion transport.
Ultrastructure of the human intervertebral disc: II. Cells of the nucleus pulposus
Authors: Trout Jerome J. , Buckwalter Joseph A. , Moore Kenneth C. 
Published: February 2005

AbstractThe cells of the intervertebral disc exist in a unique environment; not only are discs subject to large mechanical loads, they are the largest avascular structures in the body. To describe the ultrastructure and age changes in cells from human nucleus pulposus, we studied these cells in individuals ranging in age from the 26th week of fetal life to 91 years. Viable chondrocyte‐like cells existed in specimens from all ages. The presence of Golgi cisternae and well‐developed endoplasmic reticulum in these cells suggests that they are capable of producing and maintaining the extracellular matrix. Necrotic cells were also present in all samples, and many cells which appeared viable when examined by light microscopy proved to be necrotic when examined by electron microscopy. The percentage of necrotic cells increased with age from 2% or less in fetal specimens to over 50% in adults. In addition, with age, a distinct pericellular matrix or “nest,” consisting of collagen fibrils, fine filaments, dense particles, and banded structures, formed around most cells with no apparent preference for viable or necrotic cells. Nest formation and increasing density of the cell nests may reflect accumulation of cell products.
Ultrastructural features of the cell surfaces of uterine and trophoblastic epithelia during embryo attachment in the cow
Authors: Guillomot Michel , Guay Patrick 
Published: February 2005

AbstractUltrastructural features of the bovine uterine and trophoblastic epithelial cell surfaces were studied by scanning electron microscopy (SEM) at the time of attachment. Apical cytoplasmic protrusions were observed on the uterine cell surface from cyclic animals on days 12–16 during the luteal phase and disappeared thereafter. However, in pregnant animals, these cytoplasmic protrusions were observed until day 21 (attachment stage). These structures suggest that the uterine cells possess secretory and/or endocytotic properties.Before the attachment stage the trophoblastic cell surface was uniformly covered by slender microvilli. At the beginning of conceptus attachment the microvilli disappeared and the trophoblastic cell surface became smooth. On areas of the conceptus facing uterine gland openings, papillae developed and filled the glandular lumen. These were interpreted to be a system by which the conceptus is immobilized on the uterine epithelium and/or a histotrophic mechanism for absorbing glandular secretory products.
Early pectoral fin development and morphogenesis of the apical ectodermal ridge in the killifish, Aphyosemion scheeli
Authors: Wood Andrew 
Published: February 2005

AbstractUsing scanning electron microscopy it has been found that in the killifish the distal epithelium of the pectoral fin bud forms a morphologically distinct apical ectodermal ridge along its entire distal margin. This ridge is a relatively more prominent feature than its counterpart in various tetrapod systems. At a later stage the ridge becomes folded internally and leongates distally marking the transformation of the ridge into a fin fold. By continued distal growth the fin fold develops into a semicircular swimming‐paddle. Collagenous rays or actinotrichia differentiate in a highly ordered arrangement close to the epithelial basement membrane within the space enclosed by this elongating fin fold and apparently support the early swimming‐paddle. During the ridge‐to‐fold transition the fin bud displays a dorsal deflection of approximately 45° and a caudalward rotation about the axis of the fin itself. This change in orientation results in close apposition of the developing fin structure to the flank.
Morphometric studies of the alveolar epithelium in dog lungs in vivo after increased rates of outward filtration
Authors: Defouw David O. , Chinard Francis P. 
Published: February 2005

AbstractIncreased pulmonary artery pressures and decreased albumin concentrations were established in dogs, in vivo, by circulatory overload and by plasmapheresis. Each change, occurring singly, would be expected to produce an increase in outward filtration rate. The ultrastructure of the alveolar epithelium after the production of this presumed increase in filtration was evaluated by established morphometric techniques. The extent of extravascular fluid accumulation was assessed by multiple indicator‐dilution studies and by light microscopic analysis. Previous studies from this laboratory (DeFouw and Berendsen, 1979; DeFouw, 1980) define increased alveolar surface densities, increased type I cell vesiculation, and depleted type II cell lamellar body contents after increased filtration had induced septal edema and alveolar flooding in isolated perfused dog lungs. In the present study septal edema and alveolar flooding were not detected. Nor were changes observed in either alveolar epithelial cells or in alveolar configurations. However, there was significant accumulation of extravascular fluid in cuffs around extraalveolar vessels. These results are consistent with the interpretation that the initial stage of cardiodynamic edema formation, namely, peri‐vascular cuffing, is not associated with structural aberrations of the alveoli or their lining epithelial cells, in vivo. Since such changes were detected previously in isolated lungs after development of the final stages of edema, namely, septal fluid accumulation and alveolar flooding, additional studies of septal edema and alveolar flooding in intact animals are necessary to establish functional correlates to ultrastructural aberrations in severely edematous lungs.