摘要:

AbstractBackground: Packets of helical filaments have been observed in the outer compartment of occasional mitochondria in many cell types in a variety of animals. The compositon and funcation of these intramitochondrial helical filaments (IMHF) are unknown.Methods: IMHF wre induced in a hepatic mitochondria by administration of ethanol in the drinking water of rats. Hepatic mitochondria were isolated and ruptured by osmotic shock, relasing their IMHF. To purify these structures, the IMHF‐containing supernatant was further fractionated by ammonium sulfate precipitation, a 50–60% solution of this reagent being the most effective in this regard. Isolated IMHF were examined by electron microcopy and were analyzed by SDS‐PAGE.ResultIsolated IMHF closely resembled their in situ counterparts: they had a right‐handed helical structure with a 16 nm pitch. SDS‐PAGE analysis revealed that they contained three polypeptides with weigh tmolecular of 135, 98, and 53 kD, respectively.Conculusions: These observations will stand as a aseline for comparisons with IMHF that occur naturally or that are induced in other cell types by other kinds of experimental manipulation. © 1995 Wiley

ISSN:0003-276X    

DOI:10.1002/ar.1092410202

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

年代:1995

数据来源: WILEY

摘要:

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

ISSN:0003-276X    

DOI:10.1002/ar.1092410203

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

年代:1995

数据来源: WILEY

摘要:

AbstractBackground: Milky spots in the greater omentum of some animals are well organized perivascular infiltrated of leucocytes, and are considered to have characteristics of secondary lymphoid tissue. To determine whether milky spots in the human greater omentum can also be regarded as secondary lymphoid tissue, we studied milky spots in an unstimulated state.Methods: Patients were selected on the basis of absence of disease in the peritoneal cavity that might influence the state of the milky spots. Using monoclonel antibodies aganist macrophages, B‐lymphocytes and T‐lymphocytes, and immunoperoxidase labeling, the number of these cells and their location in milky spots were studied by light microscopy. However, the stromal components of the greater omentum, especially those within the milky spots, were studied by electron microscopy.Results: Milky spots in the human greater omentum are relatively uniform vascularized accumulations of mononuclear cells comprising macrophages (67.9% ± 9.4, mean ± standard deviation), B‐cells (10.1% ± 3.4), T‐cells (10.2% ± 3.7), and mast cells. However, no special B‐cells and T‐cell areas could be distinguished. On the ultrastructural level it was demonstrated that macrophages are present in different stages of maturation and can enter or leave the milky spots. Furthermore, no cells characteristic of secondary lymphoid organs, such as interdigitating cells or follicular dendritic cells, were seen.Conclusions: These data indicate that unstimulated milky spots in the human greater omentum are to a great extent just a preformed specific accumulation of primarily macrophages within the stroma of the greater omentum, and therefore, cannot be regarded as true secondary lymphoid tissue. Milky spots could serve as a gateway for, as well as a provider of pertioneal macrophages when the intra‐abdominal status so requires.Finally, the data from this study are compard with the data of other studies of human milky spots and those in animals. © 19

ISSN:0003-276X    

DOI:10.1002/ar.1092410204

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

年代:1995

数据来源: WILEY

摘要:

AbstractBackground: Tracer studies are a important tool to obtain information about the processes involved in the immunological response. Colloidal gold is widely used as a tracer, but its small size of label can cause some difficulty during low‐resolution analysis. To overcome this difficulty, se developed a new method to follow the route of tracer movement within lymph nodes.Methods: We applied conventional X‐ray analysis, X‐ray flurescence analysis (XFA) subtractional microscop using synchrotron radiation (SR) beam, light mycroscopy, and ultrastructural analysis to study the distribution and quantity of colloidal gold coupled with albumin with rat parasternal lymph node 2, 4, 6, 8, and 10 h after intrapleural injection of the tracer.Results: At all the time points XFA‐SR revealed that racer formed a circle with a maximum concentration in the node periphery. XFA‐SR measured colloidal gold concentration in the nodes reached its maximum (0.5−0.75 weight%) in 6–8 h. Substractional microscopy revealed superficially located groups of cells filled with colloidal gold tracer. Light microscopy and ultrastructural analysis confirmed that the tracer was concentrated in the reticular cells, situated in the sinuses of the node. Sinusoidal reticular cells concentrated tracer at much higher rates than sinusoidal macrophages. Four hours after injection, gold appeared in the lysosmes of the follicular reticular cells. At the same time point, evidence of antigen presentation was obtained. Antigen presentation proved to be an extremel sentation was obtained. Antigen presentation proved to be an extremely rare event since only one ultrastructural incident was found in 150 analysed grids.Conclusion: SR is a valuable tool for the analysis of gold tracer passage with in the living organism. © 1995 W

ISSN:0003-276X    

DOI:10.1002/ar.1092410205

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

年代:1995

数据来源: WILEY

摘要:

AbstractBackground: There has never been a study of the components of germ cells as they progress through spermatogenesis.Method:The structural changes taking place in rat germ cells, from spermatogonia to late supermatids, were studied utilizing morphometric techniues conducted largely at the ultrastructural level.Results:Volume and surface area parameters for virtually all cellular and subcellular features were obtained for nine periods during the spermatogenic cycle. Virtually of germ cell components show dynamic properties associated with specific phases of their development.Conclusions: The data provided can be used in an objective wey to characterize structural changes to funcational properties of germ cells. © 1995 Wiley‐Liss, I

ISSN:0003-276X    

DOI:10.1002/ar.1092410206

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

年代:1995

数据来源: WILEY

摘要:

AbstractBackground: Little information is available on the structural relationship of cumulus‐oocyte complexes and the oviductal Wall during the transport of cumulus‐oocyte complexes.Methods: To this end, morphological changes of the oviductal wall during the passage of unfertilized cumulus‐oocyte complexes were examined chronologically in ICR mice 25–27 days of age ijnected with PMSG and hCG. Mice were sacrificed at 12, 14, 16, 18, and 24 hr after the injection of hCG to remove oviducts, and the height of mucosal folds, muscle ayers, and epithelial cells waas measured in the serial sectios stained with hematoxylineosin or colloidal iron.Results: The height of the mucoal fold and muscle layer where cumulusoocyte complexes were located was less tan that of the adjacent portions. At 12–18 hr of hCG injection (∼2–8 hr after ovulation), the ova with surrounding cumulus cells lie free in a wide lumen, and the muscular tissue consists of only 2 or 3 layers of cells, arranged mostly longitudinally. However, a neighboring portion without cumulus‐oocyte complexes, where the folds meet in the middle, appreciably restricts the free space in the lumen. After 24 hr of hCG administration, structural changes in the oviductal wall, where cumulus‐oocyte complexes were located, were no longer aparent. The number of cumulus cells surrounding the oocyte decreased during the passage through the oviduct. AT 12–18 hr after hCG injetion, ∼140 cells were identified in the largest cros section of a cumulus‐oocyte complex, but after 24 hr of hCG administration (∼14 hr after ovuluation), an oocyte was surrounded with only (∼14 hr after ovulation), an oocyte was srrounded with only ∼25 cells.Conclusions: These results indicate that oocyte‐cumulus cell complexes influence the structure of the oviductal wall during the passage in the

ISSN:0003-276X    

DOI:10.1002/ar.1092410207

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

年代:1995

数据来源: WILEY

摘要:

AbstractBackground: Freemartinism occurs in some speices of ruminants and affects most female bovine fetuses in hterrosexual, multiple pregnancies owing of susion of the chorionic blood circulations soon after implantation. Maldevelopment of the ovaries and Müllerian ducts have been described and recognized as resulting from exposure of their respective primoridia to an excess of anti‐Müllerian hormone. The Present study aimed to analyse the prenatal growth the development of the gubernaculum in freemartins to find out its pssible affliction through foetal testis hormones derived from their male co‐twin.Methods: Histolgical sections of young and frawings and photographs of further developed freemartins and conrol male and female bovine foeuses were analysed. The specimens had been collected ealier for analsis of the time course of male and female gonadal and gential development and its impairment associated with freemartinism.Results: The gubernaculum of 35–40 day‐old male and female fetuses was in the intial stage of development and of similar appearance in all specimens. Gubenacula of 60–70‐day‐old male fetuss differed from those of females of similar age in various respects: the male gubernaculum size was larger and extension of the processus vaginalis was deeper. Freemartins showd and intermediate development with some individuals resembling male and othes resembling female agemates. During furher development, gubernacula in males developed into muscular cremaster sacs, whereas those in females generally did not develop beyond the size and structural complexity of 70‐day‐old foetuses. Beyond day 70 of fetal life, gubernaculum development in freemartins definitly showed male characteristics with respect to size and growth of a processus vaginalis with a cremaster muscular wall. The male‐like pattern of the outgrowth of the processus vainalis changed during the second half of prenatal life. Rather than its further deepening as in mals, this structure became inveted to become emerging as a papilla‐like structure from the inguinal abdomen bottom. An explanation is proposed for this unprecedented inversion, taking into account: (1) the faster and higher reaching rightsided ascent of the kidneys and gonads, (2) the femalelike outgrowth of the cranial gonadal suspensory ligaments, and (3) the absence of scrotum development. The ovaries and mesonephric remnants in developing freemartins, during their ascent together with the kidneys while remaining attached to the bottom of the developing processus vaginalis sacs via the gubernaculum ligament, are proposed to act together to pull up the bottom of the processus vaginalis sacs. From this action, “inverted hernia sacs” result as the irreversible consequence.Conclusion: The data support the concept that foetal testes act, via as an yet unidentified third hormone, to establish malelike development of gubernacula into muscular cremaster sacs. Further work is required to reveal the identity of this hormone. Furthermore, the apparent similarity of the freemartins' inverted processus vaginalis sacs and the fetal rodents' gubernacular cones suggests that the ruminants' and rodents' processus vaginalis are essentially similar structures. Thus there is no longer an urgent need to distinguish between two different types of gubernaculum development and testis descent in rodents and ruminants, respectively, and involving or not fetal gubernacular cones. The present observations may thus contribute to the development of a unified hypothesis for sexually dimorphic development of the gubernaculum throughout the mammalian cl

ISSN:0003-276X    

DOI:10.1002/ar.1092410208

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

年代:1995

数据来源: WILEY

摘要:

AbstractBackground: There is little information about the distrib ution of cytoskeletal components in the testes of teleost fish. The aim of this (tublin, actin, vimentin, desmin, and cytokeratins) in the sertoli cells ofGambusia affinis holbrookiand in their efferent duct epithelial cells which are possibly orginated from the Sertoli cellsMethods: Light and electron microscopic immunocytochemical studies and Western blotting analysis were performed in G.affinistestis.Results: Actin immuncor eaction was observed in the Sertoli cells at all spermatogenic stages, although the intensity of the reaction varied from one state to another. Sertoli cells that support supermatogonia or supermatocytes showd a weak immunoreaction which was uniformly distributed throughout the cytoplasm and somewhat more concentrated at the level of the inter‐Sertoli specialized junctions, Immunoreaction to actin increased during the first states of supermiogenesis and was manly localized beneath the plasma membrane. This immunoreacction was more intense in the basal than in the aical ctoplasm of Sertoli cells. In a more advanced stage of supermiogenesis, actin immunoreaction become stroger in the apical cytoplasm where Sertoli cells displayed cytoplasmic projections around each supermatid. After sperm release, the apical Sertoli cell cytoplasm still showed an intense actin immunoreaction. Intense immuncreation to actin was also observed in the epithelial cells lining the efferent ducts. Immunoreaction to tubulin was diffuse throughout the Sertoli cell cytoplasm. No immunocreation to vimentin or desmn was observed in the Sertoli cells during the spermatogenic process. Immunoreation to both vimentin and desmin was observed in the efferent ducts cells. Desmin immunoreaction was also observed in the seminiferous tubule boundary cells, mainl in the sections showing germ cell cysts at the last stages of spermiogenesis and in the peritubular cells that surrounded the efferent duct epitheium. Immunoreaction to cytokeratins was found in the endothelium of testicular blood vessels but not in the Sertoli cells or in the efferent duct epithelium.Conclusions: Immunoreaction pattern to cytoskeletal proteins in the Sertoli cells of G.afinis: differs from that reported in mammalian Sertoli cells. These differences include the distribution of action filaments and the absence of dectectable vimentin immunoreaction in G.affinis: Sertoli cells. © 1995 Wiley‐Liss,

ISSN:0003-276X    

DOI:10.1002/ar.1092410209

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

年代:1995

数据来源: WILEY

摘要:

AbstractBackground: The ovary of adult rats expresses two types of cytoplasmic fatty acid binding proteins (FABP), i.e., Heart FABP (H‐FABP) and intestinal 15 kDa proteins (I‐15p). We studied immunohistochemically the cellular localizations of these FABPs in the ovaries of rts at various postnatal ages and in the ovaries of immature (3‐week‐old)rats treated with pregnant mare serum gonadotropin (PMSG) and human chorionic gonadotropin (HCG).Methods: The cryosections of ovaries were incubated with polyclonal antibodies aganist H‐FABP and I‐15P, and the immunoreactions were visualized at both light and electron microscpic levels.Results: The immunorectivity for H‐FABP occurred temporarilly in tthe follicular epithelian (granulosa) cells from 3 days to 2 weeks post partum, and then was localized exclusively to the theca/interstitial gland cells from 2 weeks to adulthood. In contrast, the immunoreactivity for I‐15P appeared temporarily in a small subsct of theca/intersitial gland cells from 2 to 3 weeks, disappeared at 4 weeks, and was localized exclusively to the corpus luteum cells after the onset of ovulation in the animal around 5 weeks. In the immature rat ovaries induced to ovulate by treatment with gonadotropins, I‐15P‐immunocreative cells were first recognized in the luteinized granulosa layer of large preovulatory follicles, and increased in number progressively in the developing corpora lutea after the ovulation.Conclusions: Two type of FABPs are expressed in ditinct steroid‐producing cell types of rat ovary, and their expressions seem to be regulated in results suggest that FABPs play specifie roles in the ovarian hormone synthesis.

ISSN:0003-276X    

DOI:10.1002/ar.1092410210

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

年代:1995

数据来源: WILEY

摘要:

AbstractBackground: Few attempts have bee made to clarify the relational development of the hypothalamo‐adenohypophysial and neurohypophysial systems in species higher than amphibians.Methods: The appearance and Topographical distribution of endocrine and neuroendocrine cells and fibers in these systems were immunohistochemically examined in the larvae ofXenopus laevis: from immediately before hatching (stage 32, Nieuwkoop and Faber's classification) to the end of metamorphosis (stage 66).Results:(1) Each endocrine cell differentiated until the middle premetamorphic period. MSH cells intially appeared in the posterior half of the pituitary anlage at stage 35/36, followed by the fidderentiation of GH cells at stage 39 in the middle part, PRL cells at stage 46 in the anterior half of the pituitary anlage, and LH cells at stage 50 in the posterior two thirds of the pares distalis. With the progression of development, the cells which differentiated at early stages shifted from their intial positions; MSH cells, to the pars intermedia; and GH cells, to the posterior half of the pars distails. 2) oxytocin and vasopression fibers were observed at stage 47/48 in the median eminence, and converged to the pars nervosa at later stages. 3) Neruoenmorphic to prometamorphic peripd: SOM fibes, at stage 45: CRH, 47/48; GRH, 48; dopamine, 58; and LHRH, 60. The cells containing these hormones were observed in the (presumptive) preoptic and/or infundibular nucleei.Conclusion: These results suggest the floowing three chronological steps in the development of hypothalamo‐hypophysial systems and their target organs: independent development of target organs at early developmental stages; appearance of hypophysial hormones to control the development of target organs at middle developmental stages; appearances of hypothalamoic hormones to control the function of maturation of the hypophysis at late developmental stages. © 1995 Wiley‐Lis

ISSN:0003-276X    

DOI:10.1002/ar.1092410211

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

年代:1995

数据来源: WILEY