摘要:

AbstractThe intramembrane particles on plasma membranes of erythrocytes of Syrian hamsters afflicted with hereditary muscular dystrophy were compared to those from normal controls by freeze‐fracture analysis. The reduced number of particles in both fracture faces of dystrophic erythrocyte plasmalemmae, as compared to that of control red cells, was found to be highly significant (P=.001). Results of this study therefore, support the concept of a generalized membrane defect (abnormality) in muscular dystroph

ISSN:0003-276X    

DOI:10.1002/ar.1092150202

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1986

数据来源: WILEY

摘要:

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 gro

ISSN:0003-276X    

DOI:10.1002/ar.1092150203

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1986

数据来源: WILEY

摘要:

AbstractThe present paper reports on differences between the root‐ and crown‐analogue dentin portions of the continuously growing mouse incisor. Conventional light microscopy and radioautography were used to study dentin formation and the uptake of [3H]‐proline and [3H]‐serine. It was found that, although the dentin apposition rate along the crown‐analogue part (covered by enamel) equalled or slightly exceeded that along the root‐analogue part (covered by cementum), the processing of predentin into dentin was considerably faster in the root aspect.Comparison of the two dentin portions at the ultrastructural level revealed that differences occurred in the morphology of the secretory granules of the odontoblast layer. Two types of granules were observed: those that were and those that were not loaded with electron‐dense particles of 30 nm diameter. While the former type was most frequent along the crown‐analogue aspect of the incisor, the latter type was particularly found along its root‐analogue aspect. This difference may reflect differences between the two dentin portions in the composition of the nonc

ISSN:0003-276X    

DOI:10.1002/ar.1092150204

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1986

数据来源: WILEY

摘要:

AbstractOne of the components of the fibrous sheath was localized in the spermatids by the immunocytochemical method using the monoclonal antibody, K32, against the fibrous sheath of mouse mature epididymal sperm. The K32 immunoreaction was first detected in the cytoplasm of spermatids at stage 14 and appeared to increase in intensity at stage 15. At this stage, the framework structure of the fibrous sheath was formed completely in the tail, but the positive reaction in the fibrous sheath was observed only in the proximal portion of the principal piece. This change in the antigenicity of the fibrous sheath proceeded in a proximal to distal direction, which was opposite to the mode of formation of the framework structure in the fibrous sheath. Finally, the entire fibrous sheath strongly reacted to the K32 antibody at stage 16, while the reaction in the cytoplasm ceased to occur.These observations indicate that the fibrous sheath matures with immunologically detectable changes in its components following formation of the framework structure. In consideration of the retrograde progression of the cytoplasmic reaction, the fibrous sheath components may possibly be transported from the spermatid cytoplasm into the principal piece.

ISSN:0003-276X    

DOI:10.1002/ar.1092150205

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1986

数据来源: WILEY

摘要:

AbstractThe lungs of male LAF1mice 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 LD50for 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 disc

ISSN:0003-276X    

DOI:10.1002/ar.1092150206

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1986

数据来源: WILEY

摘要:

AbstractA single endotracheal instillation of porcine pancreatic elastase into hamster lungs induces morphological changes that can be detected as early as 15 min after the instillation of enzyme. Lung tissue from animals sacrificed at six time points between 15 min and 3 hr after enzyme instillation was examined for ultrastructural alterations. There were few of these alterations and they were highly focal, but they included damaged epithelial cells and partially digested elastic fibers that occurred both in the parenchyma and the pleura.A cytochemical technique employing N‐t‐Boc‐L‐alanine‐p‐nitrothiophenyl ester as a substrate for elastase‐like enzymes was also used in an effort to locate pancreatic elastase shortly after instillation into the lungs. Reaction product was observed on the alveolar surface and in pinocytotic vesicles of alveolar type I cells, in connective tissue areas, in fibroblasts, and in pinocytotic vesicles of capillary endothelial cells. The location of reaction product coupled with ultrastructural alterations in the tissue suggests that pancreatic elastase instilled into the trachea may reach the interstitium in two ways: First, transport may take place across intact alveolar type I cells via pinocytotic vesicles, and second, a small amount of enzyme may gain access to the connective tissue after the disruption of epithelium in a few highl

ISSN:0003-276X    

DOI:10.1002/ar.1092150207

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1986

数据来源: WILEY

摘要:

AbstractThe aim of this immunohistologic study was to determine how lymphocytes and accessory cells associated with antigen processing are distributed in the domes of Peyer's patches. Monoclonal antibodies against mouse B cells (anti‐B220), T cells (anti‐Thy‐1.2), T helper cells (anti‐L3T4), T cytotoxic/suppressor cells (anti‐Lyt‐2), macrophages (anti‐Mac‐1), and Ia+ cells (anti‐I‐Ad) were applied to cryostat sections of mouse Peyer's patches and visualized with peroxidase‐conjugated avidin‐biotin complexes (ABC). The subepithelial dome, the dome epithelium, and the follicle crypt epithelium were each surveyed for cells labeled with these antibodies. Each region had a characteristic and nonrandom distribution of labeled cells. In the subepithelial dome, B cells, T helper cells, macrophages, and Ia + accessory cells formed a cellular meshwork between follicle and the dome epithelium. T cytotoxic/suppressor cells were sparse beneath the epithelium. In the dome epithelium, solitary and paired lymphocytes occurred both above and below the level of epithelial cell nuclei. B cells predominated, and both T helper cells and T cytotoxic/suppressor cells were present. B cells sometimes aggregated in small clusters. Macrophages were rarely observed in the epithelium. The distribution of cells in the dome epithelium was distinctly different from non–Peyer's patch intestine where T cytotoxic/suppressor cells predominated and B cells were few in number. Although lymphocytes were usually absent in crypts outside Peyer's patches, in follicle crypts B cells and T cells were seen but not Ia + accessory cells or macrophages. Most of the T cells in the crypt epithelium were T cytotoxic/suppressor cells. These characteristic distributions in Peyer's patch domes and crypts are consistent with current hypotheses that antigen processing takes place in follicle domes and that specific lymphocytes may participate in fine regulation of stem cell different

ISSN:0003-276X    

DOI:10.1002/ar.1092150208

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1986

数据来源: WILEY

摘要:

AbstractWe divided 116 rats weighing 50 gm into four groups with tails either left in situ or transplanted as follows: (1) straight in situ: untreated controls; (2) bent in situ: five caudal vertebrae (CV) in the loop; (3) straight transplants: three CV skinned and transplanted autologously; and (4) bent transplants: five CV skinned, bent to form a loop, and transplanted autologously. Tails were radiographed weekly up to 6 weeks and at 12 weeks, and microradiographic and histological studies were undertaken on selected specimens. At 12 weeks the bones in the apex of the loop of tails left in situ appeared bent with a straight‐to‐convex shaft on the outer side and a thicker, more concave one on the inner side. In the transplanted bent segments the bone shaft died and initially the reverse occurred: the outer shaft thickened and the inner resorbed completely. A new concave inner diaphysis then formed so that the bones in both instances were essentially similar in final shape. In the bent transplants the surviving osteogenic tissues regenerated and, adapting to the altered forces, formed a new bone shaft. This involved a change in the direction, amount, and nature of endochondral, periosteal, and regenerative growth and subsequent remodeling of bone. The results support previous observations that, within limits, the strain in the osteogenic envelope is an important factor in adaptation of bones to changing stress and that, where the envelope is deficient, the surviving tissues have the capacity to regenerate and repair defects in the bone so that it best resists the changing stresses applied to

ISSN:0003-276X    

DOI:10.1002/ar.1092150209

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1986

数据来源: WILEY

摘要:

AbstractSevere cardiac malformations may involve the atrioventricular valve region, but the sequence of embryonic development of this important area has been little studied. In particular, the basis of atrioventricular muscular discontinuity, except at the conduction system, has remained unexplained. To examine this question, serial histologic sections of human embryos from the Carnegie Embryo‐logical Collection and from the Hopkins Pathology Collection were studied and six embryos were reconstructed. The atrioventricular sulcus can be identified in Carnegie stage 10 as an indentation or crease on the right side separating the heart tube from the umbilical vein. By stage 12 the sulcus has deepened and rotated anteriorly as the atria appear and the heart tube elongates rapidly within the confining pericardial space. Selective accumulation of cardiac jelly on the endocardial aspect of the constriction of the heart tube produced by the atrioventricular sulcus is pronounced by stage 14. By stage 16 the separation of the atrioventricular orifice into right and left components is well advanced, and by stage 18 the septation of the atria and ventricles is largely complete. The muscular connection between the atria and the ventricles becomes interrupted around most of the artioventricular sulcus, except for the His bundle, during the latter part of the embryonic period. The topography of the original sulcus assumes a catenoidal or saddle‐shaped configuration, i.e., convex in one plane and concave in the perpendicular plane. The tension and pressure relationships in such a structure would favor cardiac jelly accumulation and the eventual disintegration of lines of myocyte connections passing across the groove. The preservation of the His bundle connection is explained by the failure of the sulcus to completely encircle the he

ISSN:0003-276X    

DOI:10.1002/ar.1092150210

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1986

数据来源: WILEY

摘要:

AbstractThe structure of the satellite cell sheath of frog dorsal root ganglion cells was studied in thin sections and freeze‐fracture replicas. The sheath around the cell body is composed of thin satellite cell lamellae closely applied to the neuronal plasma membrane. At the axon hillock the sheath divides into outer and inner components separated by a broad space containing a distinctive extracellular matrix and occasional flattened satellite cell processes. The sheath around the initial segment is usually multilayered but less compact than that around the cell body, and in some places it exhibits node‐like interruptions. Apart from occasional particle groupings characteristic of tight junctions and gap junctions, the satellite cells display homogeneously distributed intramembranous particles in both fracture faces in all regions of the she

ISSN:0003-276X    

DOI:10.1002/ar.1092150211

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1986

数据来源: WILEY