bluuebunny/crossref_metadata_2025_split huggingface dataset:
Characterization of a testis specific protein localized to endoplasmic reticulum of spermatogenic cells
Authors: Ohsako Seiichiroh , Bunick David , Hess Rex A , Nishida Takao , Kurohmaru Masamichi , Hayashi Yoshihiro 
Published: February 2005

AbstractBackground: In order to understand the mechanism of spermiogenesis, it is important to characterize germ cell specific genes and proteins expressed during spermatogenesis. We previously reported that a mouse monoclonal antibody, 1C9, raised against golden hamster testis homogenate, recognized a 103 kDa protein in hamster spermatogenic cells (Ohsako et al.; J. Vet. Med. Sci., 53:969–974, 1991). In the present study, we have determined the precise stage and intracellular localization of this protein.Materials and Methods: Hamster, mouse, and rat tissues were used for immunocytochemistry, SDS‐PAGE, and immunoblotting. Immunoelectron microscopy was performed using Lowicryl K4M embedded hamster testis and colloidal gold conjugated second antibody. Furthermore, immuno‐affinity purification was carried out using a 1C9‐Sepharose column.Results: In immunoblot analysis, 1C9 also recognized a 103 kDa protein and a 101 kDa protein in the rat and the mouse testes, respectively. Ten different hamster tissues other than testis did not show reactivity against 1C9. In immunostained paraffin sections of hamster testis, the initial staining appeared in middle pachytene spermatocytes and persisted until maturation phase spermatids (step 15). However, it was no longer detectable in the subsequent steps of spermatids. In addition, strong staining was observed in the post‐nuclear region of elongated spermatids. Immunoelectron microscopic analysis showed that the protein was localized to the endoplasmic reticulum (ER) and nuclear envelope of spermatogenic cells, but not in the other organelles, such as Golgi apparatus and acrosome of the spermatids. This protein appears to be associated with ER membrane. Furthermore, this protein is found exclusively in the testicular microsomal fraction, not in the cytosol. By affinity purification, approximately 320 μg of the 103 kDa protein was obtained from 10 hamster testes. The purified 103 kDa protein was unaffected by N‐glycanase, indicating it does not have asparagine‐linked glycoconjugates.Conclusions: These results indicate that the protein recognized by 1C9 appears to be a unique protein that is localized in the ER and nuclear envelope of spermatogenic cells. © 1994 Wiley‐Liss, Inc.
Development of the high endothelial venule in rat lymph node autografts
Authors: Sasaki Katsunori , Pabst Reinhard , Rothkötter Hermann‐Josef 
Published: February 2005

AbstractVascular reconstruction during rat lymph node regeneration was investigated in autotransplanted mesenteric lymph node fragments, which had been implanted in the renal parenchyma. In addition to light microscopy, vascular casting and transmission electron microscopy were used. From day 3 onwards capillaries grew into the autografts together with lymphatic vessels. The capillaries showed obvious signs of proliferation by day 5. The surviving interstitial cell at the outer border of the transplant produced extracellular substance. High endothelial venules (HEV) differentiated from capillaries from about day 7. A first sign of their development was a vessel with a narrow, branching luminal space and with endothelial cells containing rich cytoplasm and small Golgi complexes. As the Golgi complexes grew and the cisternae and vesicles increased, the lumen dilated, the cell coat on the luminal surface became prominent, and, finally, lymphocytes emigrated through these venules from around day 10. The typical lymph node structure was complete by day 28. These results suggest that the interaction among the remaining interstitial cells, invading capilaries, and lymphatic penetration results in differentiation and maturation of HEV in lymph node regeneration. The development of Golgi complexes is strongly associated with lymphocyte emigration from the blood. © 1994 Wiley‐Liss, Inc.
Fine structure of taste buds located on the lamb epiglottis
Authors: Sweazey Robert D. , Edwards Chris A. , Kapp Beth M. 
Published: February 2005

AbstractBackground: Taste buds located on the aryepiglottal folds and laryngeal surface of the epiglottis are the principal receptors responsible for the initiation of the laryngeal chemoreflex. In contrast to the wealth of information available concerning the ultrastructure of oral taste buds, little comparable data exists for taste buds located at the entrance to the larynx. Therefore, the present study was designed to investigate the fine structure of taste buds located on the lamb epiglottis.Materials: Stained thick and semi‐serial thin sections from taste buds located on the lamb epiglottis were examined with light and electron microscopy.Results: Based on morphological criteria, three types of cells could be identified in the taste bud: Type I, Type II, and basal cells. Both Type I and Type II cells extended into the apical taste pore, but there were differences between these two cell types with regard to nuclear profiles, electron density, and the relative density of ribosomes, apical mitochondria, and rough and smooth endoplasmic reticulum. Basal cells did not extend a process into the taste pore. Nerve processes were observed throughout the taste bud. Synapses were observed between both Type I and Type II cells and nerve fibers. These synapses exhibited membrane thickenings and accumulations of clear and dense‐cored vesicles of varying proportions in the taste cell cytoplasm adjacent to membrane specializations.Conclusions: The taste buds located on the lamb epiglottis share several structural similarities to taste buds located in the oral cavity and other regions of the pharynx and larynx of many mammalian species. The presence of synapses on both Type I and Type II cells of the lamb epiglottal taste bud suggests that both cell types are involved in laryngeal chemorecption. © 1994 Wiley‐Liss, Inc.
Homogeneity in the distribution of matrix components in the hamster zona pellucida as revealed by backscattered electron imaging fracture‐label
Authors: Kan Frederick W. K. , Zalzal Sylvia , Roux Emmanuelle , Nanci Antonio 
Published: February 2005

AbstractBackground: Backscattered electron imaging fracture‐label (BEI‐FL), an adaptation of the fracture‐label method for scanning electron microscopy, offers the advantage of providing information about the distribution of antigenic and receptor sites with respect to the three‐dimensional organization of tissues and cells over relatively large surfaces. Recently, using post‐embedding cytochemistry on thin‐sections of Lowicryl‐embedded oocytes, a homogenous distribution of glycoproteins in the zona pellucida (ZP) was demonstrated (Kan et al., 1989. Biol. Reprod., 40:585–598, Anat. Rec., 226:37–47; Roux and Kan, 1991. Anat. Rec., 230:347–360). However, it can be argued that the chemical nature of resins and the physical conditions of tissue processing required for post‐embedding cytochemistry may introduce changes in the tissue components and result in altered distribution of components. On the other hand, freeze‐fracture exposes constituents in a minimally denaturing manner and, since no embedding media are used, binding sites are sterically available to the probe. We have, therefore, applied BEI‐FL to examine the distribution of matrix glycoproteins in the ZP of hamster oocytes.Methods: Ovaries and cumulus masses obtained from superovulated female golden hamsters were fixed by immersion in 2.5% glutaraldehyde and processed for fracture‐label. Tissues were labeled, respectively, with Wheat germ agglutinin (WGA) followed by ovomucoid‐colloidal gold, Ricinus communis agglutinin I (RCA I)‐colloidal gold or a monoclonal antibody against Hamster Oviductin‐1 followed by protein A‐gold, and then examined in the scanning electron microscope.Results: Backscattered electron imaging revealed a homogenous distribution of WGA and RCA I binding sites throughout the cross‐fractured matrix of the ZP of cvrian and postovulatory oocytes. Hamster Oviductin‐1, an oviductal glycoprotein which is transferred to the ZP of oocytes during oviductal transit, was also found to be uniformly distributed throughout the ZP of postovulatory oocytes.Conclusions: Our results indicate that BEI‐FL can be advantageously used to examine extracellular matrices and are consistent with the concept that glycoproteins are uniformly distributed throughout the ZP of the hamster oocyte. © 1994 Wiley‐Liss, Inc.
Distribution of prothymosin alpha in rat and human adrenal cortex
Authors: Garcia‐Caballero T. , Dominguez F. , Roson E. , Gallego R. , Zalvide J. , Forteza J. , Beiras A. 
Published: February 2005

AbstractBackground: Prothymosin alpha (ProT) is a polypeptide widely distributed in the organism and expressed by cell types with a high proliferative capacity. The aim of the current work was to investigate if ProT was localized in the progenitor compartment of the adrenal cortex which, following the cell migration theory, corresponds to the zona glomerulosa.Methods: We studied by immunohistochemical and in situ hybridization methods the distribution of ProT in rat and human adrenal cortex. Immunohistochemical techniques for the study of the proliferating cell nuclear antigen (PCNA) and incorporation of 5‐bromo‐2′‐deoxyuridin during DNA synthesis were also done. Immunoelectron microscopic procedures were performed to determine the exact subcellular localization of ProT.Results: ProT was found in the zona glomerulosa cells, but not in the cells of the remaining cortical layers (zonae fasciculata and reticularis). Glomerulosa cells showed immunostaining for ProT only in the nuclei, excluding the nucleoli. Variability in immunostaining intensity was found between different glomerulosa cells. In situ hybridization of ProT mRNA confirmed that ProT synthesis in adrenal cortex occurs only in the zona glomerulosa. The results obtained for proliferating cell nuclear antigen and incorporation of 5‐bromo‐2′‐deoxyuridin confirmed that adrenocortical proliferation occurs in the zona glomerculosa. Ultrastructural immunocytochemistry showed labelling for ProT over the euchromatin, but not on the heterochromatin aggregations nor the nucleoli.Conclusions: The results presented here: (1) support the migration theory for the adrenocortical cell renewal, (2) demonstrate that ProT is present in the nuclei of proliferating cells (being associated with euchromatin), and (3) suggest that the study of ProT expression would be useful in distinguishing cycling from resting cells. © 1994 Wiley‐Liss, Inc.
Development of the inlet portion of the right ventricle in the embryonic rat heart: The basis for tricuspid valve development
Authors: Wenink Arnold C. G. , Wisse Bert J. , Groenendijk Pieter M. 
Published: February 2005

AbstractBackground: Before septation the entire atrioventricular canal is connected with the ventricular inlet segment (primitive left ventricle), wheres the mature heart exhibits an exclusive connection of the right atrium to the right ventricule. The process which is responsible for this change is controversial.Methods: Graphic reconstructions of serially sectioned embryonic rat hearts as well as scanning electron micrographs of similar specimens were made.Results: The first indication of a right atrioventricular connection was seen as a groove in the atrioventricular junctional myocardium to the right of the inferior endocardial cushion. This groove expanded to form the right ventricular inlet portion. The right, inferior, and superior walls of this newly formed cavity were formed from junctional myocardium, which demarcated it from the trabeculated right ventricular portion in all developmental stages. The left wall equally developed from this junctional myocardium and formed the ventricular inlet septum. The junctional myocardium between right ventricular inlet and trabeculated portions was seen to develop into the tricuspid valve and its tension apparatus.Conclusions: The preseptation embryonic heart has no inlet portion to the right ventricle. This new cavity is created by remodelling of atrioventricular junctional myocardium. This myocardium also provides the material contribution to the tricuspid valve and its tension apparatus. Malformations of the right ventricular inlet portion and of the tricuspid valve are indissolubly linked. © 1994 Wiley‐Liss, Inc.
Restricted endothelial cell expression of gravin in vivo
Authors: Grove Bryon D. , Bowditch Ron , Gordon Tom , Zoppo Gregory Del , Ginsberg Mark H. 
Published: February 2005

AbstractBackground: Gravin, a novel, high molecular weight, intra‐cellular protein, is expressed in endothelial cells and several other adherent cell types in vitro. To gain insights into its function, we examined the distribution of gravin in tissues.Methods: Affinity‐purified polyclonal and monoclonal antibodies were raised against a bacterial fusion protein corresponding to the carboxyl terminus of gravin and against affinity‐isolated gravin. The specificity of the antibodies was characterized by immunoblotting bacterial, cell, and tissue extracts. The characterized antibodies were used to localize gravin in baboon tissue sections by immunocytochemistry and immunofluorescence microscopy.Results: The antibodies specifically immunoblotted the fusion protein and recognized either a band at 250 kDa or a doublet at 300 kDa on immunoblots of MG63 cells, HEL cells stimulated with phorbol ester, and several baboon tissues. In tissue sections, cell types that express gravin included fibroblasts, components of the peripheral and central nervous system, the adrenal medulla, the somatic layer of Bowman's capsule, cells associated with the glomerulus, and smooth muscle of certain organs. In contrast, most epithelia and all endothelia, with the exception of endothelia of the hepatic sinusoids and intestinal lacteals, lacked gravin. Levels of gravin mRNA expression in stimulated HEL cells increased dramatically when cells were stimulated in the presence of cycloheximide, suggesting that gravin expression may be partly regulated by protein‐dependent mRNA catabolism.Conclusions: These data indicate that gravin expression is regulated in endothelial cells, possibly through protein‐dependent mRNA catabolism. The strong expression of gravin in fibroblasts, neurons, and cells derived from neural crest in vivo and in adherent cells in vitro further suggests that this protein may play role in the modulation of cell motility and adhesion. © 1994 Wiley‐Liss, Inc.
Changes occurring with increasing age in the rat lung: Morphometrical study
Authors: De Dios Escolar Juan , Gallego BegoñA , Tejero Carlos , Escolar María Asunción 
Published: February 2005

AbstractBackground: It was hypothesized that the evolution towards the senile lung is progressive, being initiated in the adult stage; and for this reason changes similar to those described in the senile lung can be detected in the lungs of middle‐aged rats. To test the hypothesis, the following design was used. The lungs of two groups of rats, adult (mean age of 16 weeks) and middle‐aged (mean age of 56 weeks) were morphometrically compared.Methods: Thirty‐one Wistar rats were used for the study; their lungs were processed histologically. The microscopic fields were analysed in a computer, and 20 variables were quantified. These were grouped into (a) variables which describe the shape and size of the distal airspace, (b) variables which describe the distal lung tissue, and (c) variables which describe elastic fibers. The results were statistically compared: correlation tests were carried out, and the specificity, sensitivity, and misclassification indices were calculated.Results: All the results of the variables which define the size of the air‐spaces were found to be significantly higher (P<0.0001) in the middle‐aged animals; the results obtained when the lung tissue was quantified directly from the histological section suggested a loss of tissue in the middle‐aged animals. However, when these data were converted into absolute values, no loss was indicated in the total lung tissue. The values of the variables which describe the elastic fiber were found to have increased significantly (P<0.0001) in the middle‐aged animals. The misclassification index was found to be lower than 10% in six variables and between 10% and 20% in four.Conclusion: The low misclassification indices found lead us to consider that our morphometric method is ideal for distringuishing the lungs of the two groups of animals used. The results of the quantification of the variables show that the middle‐aged animals exhibit simple enlargement of the distal airspaces, without tissue loss, which coincides with the current definition of the senile lung. © 1994 Wiley‐Liss, Inc.
Electron microscopic and histochemical studies of the mononuclear odontoclast of the human
Authors: Domon Takanori , Sugaya Kazuyuki , Yawaka Yasutaka , Osanai Masakazu , Hanaizumi Yoshinori , Takahashi Shigeru , Wakita Minoru 
Published: February 2005

AbstractBackground: Osteoclasts and odontoclasts are multinucleated giant cells which resorb hard tissue by the ruffled borders. Recently, the authors reported the presence of a mononuclear osteoclast with a ruffled border in vitro. However, its presence in vivo has not been shown. To demonstrate the presence of a mononuclear odontoclast in humans, the present study used human deciduous teeth.Methods: After fixation and declacification, tartrate‐resistant acid phosphatase (TRACPase) activity was detected with the azo dye method, and then TRACPase‐positive cells were observed on resorbing areas of teeth. TRACPase‐positive cells could be distinguished from other cells by light microscopy, and the cells for investigation were serially sectioned by alternating semithin and ultrathin sections to observe their ultrastructure and three‐dimensional organization.Results: TRACPase activity was detected in both multinucleated odontoclasts and a mononuclear cell from serial sections. By electron microscopy, most of the multinucleated odontoclasts had ruffled borders and clear zones. A mononuclear TRACPase‐positive cell with a ruffled border and clear zone was reconstructed three‐dimensionally by NIKON COSMOZONE 2SA. The reconstruction showed that this cell had one irregularly shaped nucleus and a wide ring‐shaped clear zone and a small ruffled border. Under the ruffled border, this cell formed a small lacuna on the dentin surface. The results suggested that this cell was a mononuclear odontoclast.Conclusions: The present study concludes that cells with ruffled borders and clear zones observed by transmission electron microscopy can be identified as odontoclasts or osteoclasts irrespective of the number of nuclei. © 1994 Wiley‐Liss, Inc.
Androgenic control of porphyrin in the harderian glands of the male syrian hamster is modulated by the photoperiod, which suggests that the sexual differences in porphyrin concentrations in this gland are important functionally
Authors: Buzzell Gerald R. , Menéndez‐Peláez Armando , Hoffman Roger A. , Rodríguez Carmen , Antolin Isaac 
Published: February 2005

AbstractBackground: The porphyrin concentrations of the Harderian glands of Syrian hamsters show marked sexual differences, with male levels being much lower than those of females. Porphyrinogenesis is inhibited by androgens, so orchidectomy leads to elevated male porphyrin concentrations; however, a number of other procedures (some of which also lower androgen levels) prevent this. We studied the effects of short‐day photoperiods and melatonin on Harderian porphyrin concentrations.Methods: Intact, castrated, or pinealectomized hamsters of both sexes were exposed to long‐day or short‐day photoperiods. Intact or castrated hamsters were given melatonin injections in the morning or the afternoon, or were given beeswax pellets containing melatonin. After a variable period, Harderian glands were dissected and porphyrins were measured.Results: Prolonged short‐day exposure (13 weeks) led to increased Harderian porphyrin concentrations and this rise was prevented by pinealectomy. The rise in Harderian porphyrins following short‐day exposure was small, compared with that following castration. Short‐day photoperiods also prevented the rise in porphyrin levels associated with castration and this effect was prevented by removal of the pineal. Melatonin injections, whether given in the morning or in the afternoon, had no effect on Harderian porphyrin concentration of castrated male hamsters. Continuous release melatonin pellets reduced the postcastrational rise in porphyrin levels in one experiment, while having no effect in another. In female hamster, neither short photoperiods nor melatonin pellets influenced Harderian porphyrin concentrations.Conclusions: These results suggested that a factor from the pineal gland helps maintain the low levels of porphyrin which are characteristic of male Harderian glands, despite the decrease in androgen levels which typically results from exposure to short days. Morning and afternoon injections of melatonin and continuous release melatonin pellets failed to resolve the question of whether this pineal factor is melatonin. Our results demonstrated that low male and high female porphyrin levels are maintained in Syrian hamsters, despite seasonal variations in the hormonal milieu, suggesting that these sexual differences are important for the (still unestablished) function of the Harderian glands in this species. © 1994 Wiley‐Liss, Inc.
Morphometry of the kidney in rat pups from uninephrectomized mothers
Authors: Okada Toshiya , Yamagishi Tatsuro , Morikawa Yoshio 
Published: February 2005

AbstractBackground: The present study was designed to explore whether maternal renal dysfunction affects fetal kidney development and if the effects are lasting during the postnatal development.Methods: Kidneys of 1‐day‐old and 6‐week‐old pups from mothers which were uninephrectomized on day 5 of gestation were studied.Results: One day after birth, both the number of immature glomeruli and average volume of mature glomeruli of the neonates from uninephrectomized mothers were significantly larger than those from sham‐operated mothers. Six weeks after birth, no significant differences in parameters of the kidney were observed between the pups from uninephrectomized and those from sham‐operated mothers. Furthermore, blood urea nitrogen (BUN) concentration in adult female rats was determined at various days after uninephrectomy. BUN concentration in uninephrectomized rats was significantly higher than that in sham‐operated ones.Conclusions: These results suggest that the fetal kidney development is accelerated by the elevated BUN level following maternal uninephrectomy and that the renotropic activity does not last during the postnatal developmental period. © 1994 Wiley‐Liss, Inc.