bluuebunny/crossref_metadata_2025_split huggingface dataset:
Phenytoin‐induced connective tissue growth in the rat
Authors: Dill R. E. , Jones R. G. , Davis W. L. 
Published: February 2005

AbstractRats were treated daily for 9 days with 100, 50, or 25 mg/kg phenytoin i.p. This treatment resulted in a significant increase in the thickness of the connective tissue capsules of the liver, spleen, and pancreas, and of the subepithelial connective tissue of the mesentery but not the epicardium or visceral pleura of the lung where exposure to the drug was via the vascular route. Many areas of connective tissue growth exhibited obvious proliferation of fibroblasts and in some areas contained seemingly large numbers of macrophages and an increase in vascularity. It was demonstrated by electron microscopy that the macrophages occasionally were seen in intimate contact with the fibroblasts.Our observations clearly showed that intraperitoneal exposure of visceral connective tissues of the rat to phenytoin rapidly resulted in a dose‐related proliferation of that tissue. The presence of numerous macrophages leads to the suggestion that macrophage‐derived growth factor could be responsible for the increased growth.
Cell‐cell matrix interactions in induced lung injury: III. Long term effects of X‐irradiation on basal laminar proteoglycans
Authors: Rosenkrans Wayne A. , Penney David P. 
Published: February 2005

AbstractThe lungs of male LAF1 mice were locally irradiated with doses of 5, 9, and 13 Gy. The animals were killed at times corresponding to the appearance of histologically identifiable fibrosis or, for 13 Gy, at the LD50 for these doses and strain of mouse: 63, 36, and 28 weeks postirradiation (PI) respectively. Lungs were excised, incubated in buffer alone, or partially digested with enzymes for determination of relative glycosidase resistance, fixed with ruthenium red/Triton X‐100 for demonstration of basal laminar anionic sites, and processed for electron microscopy. Sham‐irradiated and untreated control groups (0 Gy, 0 times) were also processed. Tissue was examined ultrastructurally and alterations in both alveolar and capillary basal laminar anionic sites were quantitated. In each of the doses examined the number of anionic sites surpassed normal levels; however, the glycosidase resistance of the regenerated laminae at these late time points was not significantly altered from controls. This contrasts with the marked increase in the glycosidase resistance of laminae regenerating from radiation damage (4–12 weeks PI) reported earlier. The increased numbers of anionic sites were compared to expected values derived from models based on compensatory synthesis and continued accumulation and indicate close correlation with certain aspects of the compensatory synthesis model but not with others. The effects on basal laminar permeability, basal laminar thickening, and fibrotic induction are discussed.
Immunohistochemical localization of calbindin‐D28k during the development of the rabbit nephron
Authors: McIntosh James E. , Bourdeau James E. , Taylor Alan N. 
Published: February 2005

AbstractSpecific antibodies raised against a 28‐kilodalton chick intestinal calcium‐binding protein (calbindin‐D28k) were used to localize the protein immuno‐cytochemically in the developing rabbit kidney. Kidneys taken from rabbits between the 13th embryonic and 17th postnatal day were examined. Calbindin‐D28k was observed in the mesonephric duct and the ureteral bud on the 13th embryonic day. During subsequent involution of the mesonephros, the ampullae of the metanephric ureteral buds contained calbindin‐D28k. The protein was gradually lost from the ureters and the deep interstitial collecting ducts. Calbindin‐D28k was never present in the renal vesicles derived from the nephrogenic blastema, but it was present in the connecting tubule segments during formation of the arcades. The last finding supports the belief that the connecting tubule is derived from the ureteral bud.
Alterations in muscle spindle morphology in advanced stages of murine muscular dystrophy
Authors: Ovalle William K. , Dow Pierre R. 
Published: February 2005

AbstractMuscle spindles in the soleus of 1‐year‐old dystrophic mice of the C57BL/6J dy2J/dy2J strain were studied by microscopic and morphometric methods, and comparisons were made with those in age‐matched normal tissue. Transverse epon sections were cut through various regions of an individual receptor, and subsequent 90° reorientation enabled longitudinal examination of the same spindle. In dystrophy, alterations were detected in the outer capsule and consisted of a significant increase in its overall thickness in equatorial regions. Perineurial proliferation accompanied histiocyte and collagen infiltration. Within the equator, intrafusal fibers and sensory terminals appeared unaffected by dystrophy. Alterations in the intrafusal fibers were restricted to polar zones where the mean diameters of chain and bag fibers were significantly reduced. Polar chain fibers exhibited a greater degree of atrophy in dystrophy with a 40% diminution in size. Ultrastructural changes in intrafusal fiber polar regions were less pronounced compared to the surrounding dystrophic muscle. Mitochondrial alterations in affected intrafusal fibers included intramatrix inclusions and glycogen deposition. Vacuolization of the sarcoplasmic reticulum and subsarcolemmal tubular aggregates were also observed in polar regions of dystrophic chain fibers. Regional variation in spindle involvement in advanced murine dystrophy provides evidence that the equatorial contents of this receptor are sequestered from the deleterious effects of the disease. Capsular thickening in the equator may be an adaptive response, preventing the intrafusal fibers from undergoing the moderate change and atrophy observed at their polar ends.
Morphology and glycoprotein synthesis of uterine glandular epithelium in human basal plate at term: An ultrastructural and autoradiographic study
Authors: Nelson Michael D. , Ortman‐Nabi Judith , Curran Edward M. 
Published: February 2005

AbstractThis study describes the morphologic features of uterine glandular epithelium in human basal plate at term and identifies this epithelium as an active site of glycoprotein synthesis. Wedge biopsies were obtained from the basal plate at the time of repeat cesarean section from 11 normal pregnant patients at term. Biopsy specimens were either processed immediately for microscopic examination or incubated in vitro with 25μCi/cc of 3H‐galactose or 3H‐leucine. Tissues incubated with tritiated compounds (2‐hour pulse ± 3‐hour chase in nonradioactive medium) were either processed for light microscopic autoradiographic analysis or extracted for determination of trichloroacetic‐acid‐precipitable tritiated macromolecules in tissues and medium. Profiles of cuboidal‐columnar glandular epithelium were identified in the decidual component of the basal plate region adjacent to spiral arterioles and perpendicular to the inner layers of myometrial muscle. Autoradiographic and biochemical studies identified the glandular epithelium, as well as large decidual cells, to be major sites of incorporation of both 3H‐galactose and 3H‐leucine and to be prime sources for secretion of tritiated macromolecules that appeared in the medium during in vitro incubation of basal plate tissue. Ultrastructurally, the glandular epithelium was noted to rest on a basal lamina, to have lateral cell membranes with numerous desmosomes, and to exhibit an apical surface with microvilli projecting into a luminal space. Cytologic features of the cells included abundant profiles of rough endoplasmic reticulum, multiple mitochondria with lamellar cristae, a well‐developed perinuclear but nonpolarized Golgi apparatus, and nuclei containing predominantly euchromatin. Lipid droplets and glycogen deposits were present in some cells. This study indicates that uterine glands persist throughout human gestation in the basal plate and that these glands continue to be active in glycoprotein synthesis and secretion.
The distribution of 3H‐proline in alveolar bone of the mouse as seen by radioautography
Authors: Johnson Roger B. 
Published: February 2005

AbstractPrevious studies of the turnover of alveolar bone collagenous proteins have devoted little attention to the variable patterns in this process caused by bone remodeling. The present study seeks to document changes resulting from physiologic tooth movements in the incorporation and removal of the 3H‐proline label within the interdental septum of alveolar bone. One week following 3H‐proline injection, three zones could be distinguished: (1) the appositional band, (2) new bone, and (3) old bone. Radioautography demonstrated that formation of new bone on the distal wall of the septum entrapped fibers of the periodontal ligament to create Sharpey's fibers. At the alveolar crest, new bone entrapped transseptal fibers to form transalveolar Sharpey's fibers. Grain counts were made within each area and over the total septum and were compared statistically. The data strongly suggested regional variations in protein remodeling. Counts from old and new bone were significantly different from the total septum or the appositional band (P < .001). Regression lines were drawn to represent incorporation and removal of the isotope; slopes were calculated and compared statistically. The rate of incorporation and removal was significantly greater in the appositional band and in the total septum in comparison to old bone (P < .001). The rates of incorporation and removal in the appositional band, old bone, and total septum were significantly different (P < .001). Half‐life of the labeled protein of old bone was 16.78 weeks; in the appositional band, 7.66 weeks; and in the total septum, 7.64 weeks. These data suggest that regional variations in collagen remodeling must be considered in a study of interdental bone and that the total septal grain counts are not indicative of the remodeling in the component zones.
Rabbit endocervical epithelium: Morphometric analysis of secretory cell populations
Authors: Chilton Beverly S. , Sowinski J. M. , Barnes H. , McAllister C. J. 
Published: February 2005

AbstractIn this report we quantitated ultrastructural changes in two cytologically distinct secretory cell populations from the rabbit endocervix. Type I and type II cells from estrous animals differ only in the presence of one or more empty cytoplasmic vacuoles in type II cells. Comparing type II cells from 5‐day pseudopregnant (PSP) rabbits with type II cells from estrous controls, there is no increase (P>.05) in the average vacuole volume. When type I and type II cells from PSP animals are compared to cells from estrous controls, there is a decrease (P<.01) in the average cell volume, a decrease (P<.01) in the average nuclear volume, and a decrease (P<.01) in the average granule volume. This reduction in the granule content of secretory endocervical cells was correlated with a dramatic decrease in protein glycosylation into the microsomal fraction. Serum estradiol concentrations for estrous (13.7 ± 1.0 pg/ml) and PSP (18.1 ± 1.5 pg/ml) animals were comparable. However, the 36‐fold increase in serum progesterone concentrations for PSP (12.04 ± 1.7 ng/ml) animals compared to estrous (0.33 ± 0.1 ng/ml) animals may be responsible for the decrease in protein glycosylation.
Neuronal development in the trigeminal mesencephalic nucleus of the duck under normal and hypothyroid states: I. A light microscopic morphometric analysis
Authors: Narayanan Y. , Narayanan C. H. 
Published: February 2005

AbstractLight microscopic morphometric procedures were used in order to examine the effects of propylthiouracil (PTU) on the development of the mesencephalic nucleus of the trigeminal nerve in the duck. A single vascular injection of a 0.2% solution of PTU was administered at a dosage of 2 μl/gm embryo weight on embryonic day nine (E9). Control embryos received a similar dose of Ringer's solution. The following parameters of cytodifferentiation of cells of the mesencephalic nucleus of V were studied: somal area profiles, nuclear area, and nuclear cytoplasmic ratios. In addition, the frequency of beak clapping was recorded from E16. Significant differences were observed in somal area profiles in the experimental group at E16 and E18 and in nuclear area profiles from E16 through hatching. Beak activity in the experimental embryos was drastically reduced. It is concluded that PTU induces a retardation in the differentiation of cells of the mesencephalic nucleus of V which may lead to behavior deficits as evidenced by reduction of beak activity. These observations provide a basis for the study of interactions between thyroid hormone and specific neuronal systems in the emergence of an adaptive function.
Maturation antigen of the mouse sperm flagellum: II. Origin from holocrine cells of the distal caput epididymis
Authors: Feuchter F. A. , Green M. F. , Tabet A. J. 
Published: February 2005

AbstractDuring epididymal transit, the mouse sperm flagellum acquires a surface glycoprotein (SMA4) from epididymal fluid that functions as a sperm antiagglutinin. To determine the origin of this molecule, testes and epididymides of male mice were sectioned for light microscopy and stained with wheat germ agglutinin (WGA)‐peroxidase, a probe that has been used previously to examine the biology of SMA4. WGA reactivity was localized to the cytoplasm in a small population of cells in the distal caput epididymis. Testis cells and principle cells of the caput were nonreactive with WGA, while stereocilia were stained on principle cells in the corpus and cauda. The WGA‐positive cells in the distal caput were identified as holocrine cells on the basis of morphology, distribution, and PAS+ reaction. At high magnification, intense WGA reactivity was due to the presence of numerous apical granules in the cytoplasm. The location of the cells in distal caput coincided exactly with the region of tubule in which sperm first acquired SMA4 on their flagellae. These data suggest that holocrine cells near the junction of caput and corpus epididymis are the source of the sperm antiagglutinin SMA4.
Immunoultrastructural studies of human NK cells: II. Effector‐target cell binding and phagocytosis
Authors: Kang Yuan‐Hsu , Carl Mitchell , Watson Lorrita P. , Yaffe Lyn 
Published: February 2005

AbstractThe binding of NK cells to a target cell appears to be a necessary step for NK cell‐mediated cytolysis. In this report, we demonstrated effector‐target binding by immunoelectron microscopy by using monoclonal antibodies against NK cells (Leu‐7, Leu‐11a) and T‐cell subsets (Leu‐2a/T8, Leu‐3a/T4). The surfaces of NK and K562 cells were characterized by antitransferrin receptor antibody and various lectins. In addition, the controversial phagocytic activity of NK cells was studied by incubation of peripheral blood mononuclear cells with opsonized Staphylococcus aureus and labeling with anti‐Leu‐7 or anti‐Leu‐11a antibody. Results showed that only Leu‐11a+ cells displayed a broad cell‐to‐cell contact with the target by a shallow intercellular interdigitation of cytoplasmic projections, while Leu‐7+, Leu‐2a+, or Leu‐3a+ cells showed only a partial contact with target without interdigitation. The Leu‐11a+ cells were frequently observed in small clusters and in close association with monocytes. Cluster formation and association with monocytes were not observed in other NK and T‐cell immunophenotypes. In Leu‐11a+ cells conjugated with target cells, membrane‐bound granules, small vesicles, parallel tubular arrays, Golgi apparatus, endoplasmic reticulum, and small vacuoles were evident and concentrated toward the target. The surface of NK cells was intensely stained for glycoprotein by chromic acid‐phosphotungstic acid, whereas target cells were not stained. Transferrin receptors were stained only on the surface of target cells. Only the lectins RCA and UEA labeled the surfaces of both NK and target cells. Phagocytic vacuoles containing cell debris or fragments and ingested bacteria were found in the cytoplasm of Leu‐11a+ cells but not in Leu‐7+ cells. NK cells were also found within the cytoplasm of K562 target cells. All these findings suggest that Leu‐11a+ cells are the true functional NK cells involved in NK cell‐mediated cytolysis, phagocytosis, and emperipolesis. Therefore, the NK cell is probably “a phagocyte in lymphocyte's clothing.” The presence of peroxidase in the small vesicles of NK cells and endocytotic vesicles of target cells at the effector‐target contact area indicates that cytolytic enzymes or factors derived from NK cells may be transported into the target by endocytosis.
Differential technique to stain nerve cells and fibers in methacrylate sections
Authors: Toliva J. , Tolivia D. 
Published: February 2005

AbstractA simple method for the simultaneous staining of nerve cells and fibers, applicable to sections of pieces embedded in methacrylate, is described. Sections of 12 μm in thickness were attached to slides and stained for 10–18 hours in the following solution: 0.03% thionin, 0.5% formaldehyde, 0.5% acetic acid in distilled water. They were then rinsed in acetic water (0.5% acetic acid) for 30 seconds, washed in distilled water, dehydrated through 96% and absolute ethanol, cleared in eucalyptol, and mounted in Eukitt.
Endothelial vesicular system in rapid‐frozen muscle capillaries revealed by serial sectioning and deep etching
Authors: Noguchi Yasuo , Shibata Yosaburo , Yamamoto Torao 
Published: February 2005

AbstractEndothelial plasmalemmal vesicles were examined in serial sections and in deep‐etch replicas of rapid‐frozen rat muscle capillary endothelium. Numerous fused vesicles were observed in both preparations. The morphology of the vesicles in rapid‐frozen capillaries differed from that in the chemically fixed ones; rapid‐frozen vesicles were spherical rather than ovoid, and the necks of caveolae and the connecting portion of fused vesicles were wider than those of chemically fixed ones. In the serial sections, true free vesicles were rarely identified (1.6%). In the deep‐etch replicas, some of the cytoplasmic surface of vesicles had a mulberrylike appearance and intracytoplasmic fine fibrils appeared to connect the vesicles either to other vesicles or to the plasmalemma proper. Two transendothelial channels were found among 250 capillary profiles. Almost all endothelial “vesicles” proved to be invaginations of the surface membrane, and chemical fixatives did not seem to induce any substantial membrane fusion. These observations suggest that transendothelial transport of large macromolecules across continuous capillary endothelium is carried out mainly by diffusion through transendothelial channels.
Acetylcholinesterase in prenatal rat heart: A marker for the early development of the cardiac conductive tissue?
Authors: Lamers Wouter H. , Korstschot Anita Te , Los Johannes A. , Moorman Antoon F. M. 
Published: February 2005

AbstractIn rat embryos, acetylcholinesterase (AChE, EC 3.1.1.7) activity is present in a continuous sleeve of mycocytes that extends from the myocardium that is adjacent to the atrioventricular endocardial cushions via the ventricular trabeculae to the outflow tract. No activity is found in the atrial roof, in the ventricular walls and in the interventricular septum except for its subendocardial surface. AChE‐positive cells are first identified in 11‐day rat embryos, while the prototypical distribution is best demonstrable in 13‐day embryos. Part of the AChE‐positive cell system is identifiable as a precursor of the adult conduction system by topographical criteria in 16‐day fetuses and by morphological criteria in 20‐day fetuses. At birth (2 days later), AChE activity has disappeared from the cardiac myocytes except for a ring of tissue at the atrial side of the atrioventricular junction. These findings suggest that the embryonic heart can be divided into an upstream mycardium that has no AChE activity and a downstream myocardium that is characterized by the presence of AChE. Furthermore they suggest that an acetylcholine‐dependent mechanism may be responsible for the retardation of the depolarization wave in the downstream parts of the heart. Finally they show that the adult conduction system is formed by a transdifferentiation of part of a far more extensive embryonic precursor system.
Distribution of basement membrane antigens in cryopreserved early embryonic hearts
Authors: Kitten Gregory T. , Markwald Roger R. , Bolender David L. 
Published: February 2005

AbstractThe early embryonic heart is composed of two cylindrical epithelial layers, an inner endothelium and an outer myocardium. The cardiac jelly (CJ), an acellular accumulation of extracellular matrix (ECM), fills the space between the two epithelia. During development of the heart, a portion of the endothelial cells of the atrioventricular (AV) region differentiate into mesenchyme cells in a temporally and spacially specific manner. Although contiguous with those in the AV region, endothelial cells lining the ventricle never form mesenchyme in situ. At present, the mechanisms controlling the biphasic differentiation of the endothelium and the subsequent migration of cardiac mesenchymal cells are poorly understood.Although the CJ lies between two epithelial and is spatially equivalent to a basement membrane (BM), it has not traditionally been considered to be organized into a BM‐like structure. The potential significance of this observation to developmental biology lies in the possibility that BM or their individual componetns (i.e.), fibronectin (FN), laminin (LM), type IV collagen, and heparin sulfate proteoglycan (HSPG) may function as the regulatory site of epithelial differentiation and morphogenesis.A cryofixation technique was developed in order to determine the in situ immunohistochemical distribution of the BM components in the CJ. Results indicated that the CJ exists as the fusion between a larger myocardially derived BM having a lamina densa and an extended reticular lamina and an attenuated, endothelial‐associated BM composed only of a lamina densa. Except for FN, the individual BM components were not all present during early stages, but instead appeared in a sequential manner, suggesting that all components of an adult‐type BM are not required to initiate the assembly of a structural and functional BM during development. In the AV canal and outflow tract (OT), FN appeared as a progressively expanding gradient of material with the greates density nearer the myocardium.
Morphometric analysis of neuronal soma size within the motor nucleus of a transplanted murine skeletal muscle
Authors: Klueber Kathleen M. 
Published: February 2005

AbstractSince the number of motor neurons supplying a muscle graft is reduced, the peripheral field for the surviving motor neurons would be enlarged. This possible change in motor unit size may result in morphologic changes in the size of motor neurons within the motor neuron pool of the graft. The extensor digitorum longus (EDL) muscle from 19 transplanted and 17 age‐matched normal 129 ReJ female mice were injected with horseradish peroxidase in order to examine the cell size distributions of the motor neuron pools supplying these muscles. Computer‐assisted morphometric analysis of cell sizes within the motor neuron pool to the transplants indicated a singnificant shift in cell size, with the largest areas ranging between 630 and 1250 μm2. A number of the alpha neurons supplying the grafts were twice the average cell size for the control population (X = 592 μm2). The increase in the number of large motor neurons indicates an hypertrophy of neurons reinnervating the grafts. The long‐term graft is reinnervated by a decreased population of motor neurons (X = 7), which vary in size from small to very large, reflecting both changes in the possible source of the nerve reinnervating the graft as well as alteration in the size of the motor unit, respectively.