bluuebunny/crossref_metadata_2025_split huggingface dataset:
Vascular branching pattern and zonation of gene expression in the mammalian liver. A comparative study in rat, mouse, cynomolgus monkey, and pig
Authors: Wagenaar Gerry T. M. , Mocrman Antoon F. M. , Chamuleau Robert A. F. M. , Deutz Nicolaas E. P. , De Gier Corrie , De Boer Piet A. J. , Verbeek Fons J. , Lamers Wouter H. 
Published: February 2005

AbstractBackground: A significant part of the liver volume consists of regions in which hepatocytes are in close contact with large branches of the afferent (portal vein) or efferent (hepatic vein) vessels. As most studies have addressed zonation of gene expression around the parenchymal branches of the portal and hepatic vein only, the patterns of gene expression in hepatocytes surrounding larger vessels are largely unknown.Methods: For that reason, we studied the patterns of expression of the mRNAs and proteins of the pericentral marker enzymes glutamine synthase, ornithine aminotransferase, and glutamate dehydrogenase and the periportal marker enzymes phosphoenolpyruvate carboxykinase and carbamoylphosphate synthase in the rat liver, in relation to the branching pattern of the afferent and efferent hepatic veins with immuno and hybridocytochemical techniques. These patterns of expression were compared with those seen in mouse, monkey, and pig liver.Results: The distribution patterns of the genes studied appear to reflect the “intensity” of the pericentral and periportal environment, glutamine synthase and phosphoenolpyruvate carboxykinase requiring the most pronounced environment, respectively. The patterns of gene expression around the large branches of the portal and hepatic vein were found to be related to the parenchymal branches in the neighbourhood of these large blood vessels. Only the cells of the limiting plate retain their periportal and pericentral phenotype for those marker enzymes that do not require a pronounced periportal or pericentral environment to be expressed. GS‐negative areas in the pericentral limiting plate appear to correlate with a local absence of draining central veins, and become more frequent and extensive around the larger branches of the hepatic vein.Conclusions: The similarity of the observed patterns of gene expression of the genes studied in mouse, rat, monkey, pig, and man suggests that they reflect a general feature of gene expression in the mammalian liver. A comparison of mouse, rat, pig, and human liver suggests that the presence of glutamine synthase‐negative areas reflects the branching order of the efferent hepatic blood vessel. © 1994 Wiley‐Liss, Inc.
Embryonic‐maternal cell interactions at implantation in the fat‐tailed dunnart, a dasyurid marsupial
Authors: Roberts Claire T. , Breed William G. 
Published: February 2005

AbstractBackground: In marsupials implantation occurs about two‐thirds the way through the short gestation before which time the embryo is surrounded by the permeable shell membrane which prevents physical contact between the trophoblast and uterine epithelium. Although the trophoblast has been shown to be invasive to varying degrees in several species of marsupials, the ultrastructure of the embryonic‐uterine cell interactions at the time of implantation has not been described in this group.Methods: Thick plastic sections and transmission electron microscopy were employed to investigate the cellular interactions at implantation in the fat‐tailed dunnart (Sminthopsis crassicaudata), a dasyurid Australian marsupial.Results: Our results show that epithelial penetration begins when the embryo is at the late presomite/early somite stage. In the trilaminar region of the yolk sac (TYS), trophoblast cells adjacent to the embryo form desmosomes with uterine epithelial cells and also appear to fuse with them to form hybrid cells, the cytoplasm of which resembles that of trophoblast. Later in the TYS, as the placenta develops, trophoblast microvilli and larger cell processes invaginate, and interdigitate with, the highly folded maternal epithelium but do not invade it. At this time in the bilaminar, or avascular, yolk sac (BYS), multinucleate trophoblast giant cells (TGCs) from an annular region adjacent to the sinus terminalis intrude between, and possibly fuse with, the maternal epithelium. The invading TGCs spread laterally above the residual basal lamina before migrating into the stroma.Conclusions: In this species of marsupial at least, the cell interactions at the time of implantation are similar to those seen in some eutherian species despite the fact that the fetal chorion is of yolk sac rather than allantoic origin. © 1994 Wiley‐Liss, Inc.
Identification of acid cysteine proteinase inhibitor (cystatin A) in the human thymus
Authors: Söderström Karl‐Ove , Rinne Ritta , Hopsu‐Havu Väinö K. , Järvinen Mikko , Rinne Ari 
Published: February 2005

AbstractBackground: Acid cysteine proteinase inhibitor (ACPI, also called cystatin A) is a protein that is present in the epithelial cells of the skin and in the dendritic reticulum cells of lymphoid tissues. In this study the presence and cellular localization of ACPI in the thymus was investigated.Methods: The cellular and topographical location of ACPI was immunohistochemically demonstrated in the normal thymus of man.Results: ACPI was found in the cells of the‐Hassall's corpuscles and in many medullary cells. Most of these cells were epithelial cells, as shown by the results of immunohistochemical cytokeratin and epithelial membrane antigen stainings. Also, some individual cytokeratin negative but S‐100 positive medullary reticular dendritic cells were stained with ACPI.Conclusions: The finding that ACPI is constantly present in the thymus at restricted and specific cellular locations leads to the suggestion that protease inhibitors may play a role in specific thymic functions. © 1994 Wiley‐Liss, Inc.
Ultrastructural evidence for innervation of the endothelium and interstitial cell in the atrioventricular valves of the Japanese monkey
Authors: Tsumori Toshiko , Domoto Tokio 
Published: February 2005

AbstractBacground: A rich supply of nerves to the atrioventricular valve has been demonstrated. The role of the valvular nerves is still controversial because the target sites of the nerves have not been confirmed.Methods: The innervation of the atrioventricular valves of the Japanese monkey (Macaca fuscata) was examined by acetylcholinesterase staining and electron microscopy. Immunoreactivity for neuropeptide Y (NPY) was also investigated by a post‐embedding immunogold method.Results: The valvular nerve elements were clearly concentrated between the endothelium and interstital cells on the atrial side of cusps. Naked axon terminals were observed to make direct contact (20‐nm gaps) with interstitial cells and also to be in close proximity (∼200‐nm cleft) to the endothelium. NPY immunoreactivity was clearly detected on the large granular vesicles in some terminals that were in close proximity to interstitial cells and/or the endothelium.Conclusion: The present study suggests that the extensive innervation of the atrioventricular valve, which includes NPY‐containing nerves, might affect valvular function via interstitial cells and/or the endothelium. © 1994 Wiley‐Liss, Inc.
Sertoli cells in testes containing or lacking germ cells: A comparative study of paracrine effects using the W (c‐kit) gene mutant mouse model
Authors: Renato De França Luiz , Bartke Andrzej , Borg Kurt E. , Oecim Marcelo , Fadden Clare T. , Yagi Ahmed , Russell Lonnie D. 
Published: February 2005

AbstractBackground: Paracrine effects of germ cells on Sertoli cell structure were examined in a mouse model with the W locus (dominant white spotting) mutation in which animals with the W/Wv genotype (referred to as mutants) lack virtually all germ cells.Results: Morphometric determination of Sertoli cell parameters in mutant and control (+/+) animals showed that although the testes of mutant animals were about eight times smaller than controls, the numbers of Sertoli cells in the two groups did not differ. Sertoli cell volume, Sertoli cell cytoplasmic and nuclear volumes, and Sertoli cell surface area in mutant animals were significantly smaller than in control animals. Organelle volumes and surface areas, expressed per cell, did not differ significantly in the two groups with one exception: the volume and surface area of smooth endoplasmic reticulum was significantly reduced in mutant animals. Plasma testosterone levels and tissue testosterone levels/testis were normal, indicating that the effects observed in the mutant animal were not a consequence of androgen insufficiency. Plasma FSH was elevated, probably as a consequence of germ cell depletion, and was thought not to affect Sertoli cell parameters observed.Conclusions: The data suggest that paracrine interactions with germ cells do affect Sertoli cells by modifying the amount of smooth endoplasmic reticulum. These data focus attention on the function of this abundant Sertoli cell organelle in promoting spermatogenesis. © 1994 Wiley‐Liss, Inc.
Perinotochordal connective sheet of gilthead sea bream larvae (Sparus aurata, L.) affected by axial malformations: An histochemical and immunocytochemical study
Authors: Sanatamaría J. A. , Andrades J. A. , Herráez P. , Fernández‐Llebrez P. , Becerra J. 
Published: February 2005

AbstractBackground: Spinal malformations in adult teleosts occur under natural conditions and, more frequently, in culture exploitations. Skeletal deformities are linked with dysfunctions in collagen metabolism. We studied axial deviations appearing in early larval stages of cultured sea bream (Sparus aurata, L.).Methods: To evaluate connective tissue components of normal and lordotic fish we used histochemistry (alcian blue, picrosirius‐polarization, clorhydric orcein, fuchsin resorcin), immunohistochemistry (anti‐collagen I, II, III, and IV), and specific enzymatic digestions. The results were evaluated by semiquantitative methods.Results: Lordosis appeared before a vertebral column was developed, thus affecting the only skeletal structure present in the animal body, the notochord. At this stage the animal depends on the vitelline sac and an inflated swim‐bladder is missing. The region of the curvature showed strong alterations in the arrangement of the muscle bundles and irregularities in notochord and perinotochordal collagen sheet. Histochemical and immunocytochemical analysis of the periotochordal sheet revealed the presence of type II collagen, non‐sulfated glycosaminoglycans, and elastic fibers in normal and lordotic specimens. Low collagen‐proteoglycan interactions occurred in lordotic animals.Conclusions: Lordosis in Sparus aurata originated during embryonic development and was characterized by disorganized connective tissue and muscle bundles. No major differences in connective tissue constituents were seen with respect to normal specimens. © 1994 Wiley‐Liss, Inc.
Ovarian surface epithelium during ovulatory and anovulatory ovine estrous cycles
Authors: Murdoch William J. 
Published: February 2005

AbstractBackground: Ovarian surface epithelial cells have been implicated in the mechanisms of ovulation and development of common ovarian cancers. An early indication of predisposition to neoplasia is the formation of ovarian epithelial inclusion cysts. It was unclear whether morphological alterations along the ovarian surface are related directly to ovulation per se or associated endocrine parameters of reproductive cyclicity.Methods: Light microscopic disturbances in ovarian surface epithelium were monitored during synchronous ovulatory and anovulatory estrous cycles of sheep. Ovulation blockade accompanied by normal luteal phases was induced by administration of indomethacin, a prostaglandin synthase inhibitor.Results: Degenerative cells were sloughed from the apical dome of periovulatory follicles. The resultant stigma of luteinizing follicles was void of surface epithelium. Repair of the ovulatory wound by epithelium did not occur until complete involution of the corpus luteum during the subsequent estrous cycle. In a few cases inclusions containing entrapped ovarian surface epithelium were noted within adjacent stroma. Epithelia covering luteinized unruptured follicles remained intact and was not incorporated into the ovary during luteal resorption.Conclusion: Localized damage to and subsequent remodelling of the ovarian surface occurs in a cyclic fashion conjoined with the physical process of follicular rupture. © 1994 Wiley‐Liss, Inc.
New inclusion body in a rat renal cell
Authors: Chapman George B. , Sheikh Shehzad M. 
Published: February 2005

AbstractBackground and Methods: In an effort to review ultrastructural features of cells in the kidney of a male rat, transmission electron microscopy was used to study ultrathin sections.Results: One light cell in a collecting tubule contained a 2.3‐μm long linear array of electron‐dense asymmetric structures in a granular zone of greater electron density than the general cytoplasm. This inclusion body could be interpreted to consist of a parallel array of 100–150‐nm × 24‐nm electron‐dense rodlets, or a parallel array of 100–150‐nm×67‐nm tubules. The inclusion showed no association with any cell organelle. The origin, chemical nature, frequency of occurrence, and functional significance of this inclusion are unknown.Conclusions: Although this inclusion body somewhat resembles previously described inclusions or granules, the differences in dimensions, frequency, and relation to other cell structures suggest it is a new observation. © 1995 Wiley‐Liss, Inc.
Relation between the trans‐Golgi network and the Golgi stack on development of the Golgi apparatus of the ameloblast in developing rat molar tooth germs
Authors: Matsuo Saburou , Kurisu Kojiro , Kiyomiya Ken‐Ichi , Kurebe Masaru 
Published: February 2005

AbstractBackground: The problem of how the functional compartments of the Golgi apparatus organizes during cell differentiation to become a well‐formed Golgi apparatus is as yet an unresolved issue. This study was designed to define the involvement of the trans‐Golgi network (TGN) and the Golgi stack in organizing the Golgi apparatus.Methods: The distribution of the TGN marker enzyme was examined in the ameloblast of developing rat molar tooth germs using cytochemistry with Co‐enzyme A phosphatase (CoA Pase) and cytidine monophosphatase (CMPase).Results: Typically formed Golgi apparatus was observed in the secretory ameloblast but not in the presecretory ameloblast. Organization of the Golgi apparatus through the presecretory ameloblast was noted. In the presecretory ameloblast, Golgi stacks of different sizes and clusters of small vesicles were located in the cytoplasm lateral to the nucleus. The saccules with enzymes marked for TGN were also observed in the cytoplasm lateral to the nucleus. These saccules were adjacent to the cluster of small vesicles and/or the Golgi stack. Upon cell differentiation, Golgi stacks were seen in line along the long axis of the cell, and the file of the stacks in the cytoplasm lateral to the nucleus was formed. The positive saccule was seen in a parallel line equal to the length of the Golgi stacks.Conclusions: In organizing the Golgi apparatus, the development process of the TGN and the Golgi stack appear to be different, and new Golgi stacks seem to be formed through the accumulation of small vesicles near the pre‐existing TGN. © 1995 Wiley‐Liss, Inc.
Apoptosis of cultured mouse luteal cells induced by tumor necrosis factor‐α and interferon‐γ
Authors: Jo Toushun , Tomiyama Tatsuhiro , Ohashi Kazutomo , Saji Fumitaka , Tanizawa Osamu , Ozaki Masami , Yamamoto Reiko , Yamamoto Takashi , Nishizawa Yasuko , Terada Nobuyuki 
Published: February 2005

AbstractBackground: Macrophages and T lymphocytes have been identified in the regressing corpus luteum, and they are thought to participate in structural luteolysis (destruction and removal of luteal cells). Since these cells produce cytokines such as tumor necrosis factor‐α (TNF‐α) and interferon‐γ (IFN‐γ), we investigated the effects of these two cytokines on death of luteal cells in vitro.Methods: Mouse luteal cells were cultured in serum‐free medium with TNF‐α at 0,500,1,000,3,000, or 5,000 U/ml in the presence or absence of IFN‐γ at 1,000 U/ml for 3 or 6 days. Then, for estimation of the actions of these cytokines on induction of luteal cell death, we determined the number of viable cells, the percentage of fragmented DNA in total DNA extracted from cultured cells, and the percentage of cells with fragmented DNA in their nuclei by the trypan blue exclusion test, the sensitive micromethod for DNA assay, and the in situ DNA 3′ end labeling method, respectively. DNA fragmentation was also analysed by agarose gel electrophoresis, and cultured cells were examined by electron microscopy.Results:On day 3 of culture, IFN‐γ alone at 1,000 U/ml or TNF‐α alone at 500–5,000 U/ml did not decrease the number of viable cells, but a combination of IFN‐γ (1,000 U/ml) and TNF‐α (5,000 U/ml) did. On day 6, IFN‐γ alone at 1,000 U/ml or TNF‐α alone at 500, 1,000 and 3,000 U/ml did not decrease the number of viable cells, whereas TNF‐α alone at 5,000 U/ml did, and combinations of IFN‐γ and TNF‐α at 1,000, 3,000, and 5,000 U/ml decreased the number of viable cells in proportion to the concentration of TNF‐α. On days 3–6 of culture, combinations of IFN‐γ and TNF‐α that decreased the number of viable cells also increased the percentages of fragmented DNA in total DNA of cultured luteal cells and the percentages of luteal cells with fragmented DNA in their nuclei. Agarose gel electrophoresis of fragmented DNA showed a ladder‐like pattern, and electron microscopic examination showed luteal cells with the characteristics of apoptosis.Conclusions: The presence of IFN‐γ modulates the ability of TNF‐α to induce a reduction in the number of viable cells, although TNF‐α alone at high concentrations can induce a reduction in the number of viable cells. © 1995 Wiley‐Liss, Inc.
Postnatal growth of lung parenchyma in the piglet: Morphometry correlated with mechanics
Authors: Mansell Anthony L. , Collins Margaret H. , Johnson Eddie , Gil Joan 
Published: February 2005

AbstractBackground: A previous study of piglet lung growth (Mansell et. al. 1989. J. Appl. Physiol., 67:1422–1427) showed transient stiffness to changes in shape and volume immediately after birth. Later, elastic recoil was found to increase as the lung grew in weight and volume. The present study uses morphometry to test possible structural correlates of these two mechanical changes.Methods: Piglet lungs were fixed near full inflation via the airways during the immediate newborn period (6–12 hours, n=3), at 3–5 days (n=6), 25–30 days (n=5), and 80–85 days (n=3). Morphometry comprised arithmetic and harmonic mean thicknesses of alveolar septae and average mean surface curvature. Measurements of curvature and airspace volume were combined to differentiate alveolar expansion from septal proliferation as mechanisms for volumetric growth.Results: The unique mechanical behavior of the newborn lungs was associated with relatively thick alveolar septae. Marked thinning of the septae and resolution of the stiffness to shape and volume change had occurred by 3–5 days. An increase in elastic recoil during the first postnatal month was found to be associated with simple airspace expansion. The second and third months were characterized by septal proliferation and increase in arithmetic mean septal thickness but elastic recoil did not increase further. Harmonic mean septal thickness and airspace volume per gram of lung tissue did not change over the course of the study.Conclusions: 1) A relative stiffness to shape and volume change in freshly newborn piglet lung is associated with relatively thick alveolar septal walls; 2) postnatal development of piglet lung parenchyma involves septal lengthening and thinning followed by septal proliferation; 3) the initial phase of septal lengthening, rather than the later phase of septal proliferation, is associated with increase in parenchymal recoil. © 1995 Wiley‐Liss, Inc.
Localization of splenic cells with antigen‐transporting capability in the chicken
Authors: Del Cacho Emilio , Gallego Margarita , Arnal Carmen , Bascuas Jose Antonio 
Published: February 2005

AbstractBackground: The objective of the present study is to investigate the migration pattern of the splenic dendritic cell of the chicken named the ellipsoid‐associated cell (EAC) from the site of initial location at the periphery of the ellipsoid to the splenic T‐ and B‐dependent areas.Methods: Bovine serum albumin bound to biotin and conjugated to gold particles was used as a histochemically identifiable antigen detected as a peroxidase reaction. The antigen was intravenously injected, and subsequently its pattern of distribution in a time sequence and within the tissue was examined at the light and electron microsocopy levels. In addition, an hour prior to sacrifice, the chickens received a single injection of the thymidine analogue 5‐bromo‐2′‐deoxyuridine, in order to quantify the number of DNA synthesizing cells and to establish a relationship between the migrating EAC and the rate of mitosis in the white pulp.Results: The observations showed that between 12 hours and 3 days after the second antigen administration the labeled EAC, which was first located around the ellipsoid, progressively reached further areas with time towards the periarteriolar lymphoid sheaths, where newly formed germinal centers appeared. Furthermore, the rate of cell proliferation within the white pulp was associated with the arrival of the antigen‐transporting EAC.Conclusions: The results suggest that migrating EAC have a role as both antigen‐transporting cell and antigen‐presenting cell in the T‐ and B‐dependent areas, as a result of which migrating EAC is transiently found in periellipsoidal white pulp, then periarteriolar lymphoid sheaths, and finally germinal centers, where it may function as an interdigitating cell or as a follicular dendritic cell, depending on its location. Thus, we conclude that the EACs are precursors of both interdigitating and follicular dendritic cells. © 1995 Wiley‐Liss, Inc.
Dome epithelium and follicle‐associated basal lamina pores in the avian bursa of fabricius
Authors: Davenport W. D. , Allen E. R. 
Published: February 2005

AbstractBackground: The immunological role played by the avian bursa of Fabricius has been well established. Although numerous studies have also reported on the development and general morphology of this organ, some structure‐function relationships still hae not been fully explained.Methods. Bursae from chickens at three developmental stages were removed and examined by scanning electron micropscopy. Routine preparation was used as well as sonication (Microdissection). Micrographs were used for qualitative morphological study and for quantitative morphometric analyses.Results: Routine SEM observations were similar to those previously reported in the literature. Sonicated specimens allowed topographical study of various levels of surface erosion. Two types of surface cells were observed: typical absorptive epithelium and follicle‐associated epithelial (FAE) cells. Erosion of the dome surface epithelium revealed basal lamina pores n the region over the subepithelial lymphoid follicles. These pores were present at hatching. Morphometric analysis of dome and pore areas.Conclusions: Basal lamina pores may provide a communication route between the lympghoid follicles and the external environment via the FAE cells. Also, the close association between the FAE cells of the epithelial domes, the epithelial pores, the capillary complex of the previously described bursal‐blood barrier, and the subepithelial lymphoid follicles could represent a morphological “pure complex” that matures early in posthatching development and may be related to the immunological function of the bursa. © 1995 Wiley‐Liss, Inc.