bluuebunny/crossref_metadata_2025_split huggingface dataset:
Immunocytochemical localization of epidermal growth factor during the postnatal development of the submandibular gland of the mouse
Authors: Gresik Edward W. , Barka Tibor 
Published: February 2005

AbstractThe time of appearance and the pattern of localization of epidermal growth factor (EGF) in submandibular glands of mice was studied during postnatal development immunocytochemically. EGF was first detectable in the granular convoluted tubule (GCT) cells in the glands of males at 20 days of age and of females at 30 days of age. Development of GCT cells containing EGF was rapid in males, approaching adult conditions by 45 days of age. In females EGF‐containing GCTs developed more slowly and irregularly, and did not reach adult status by 45 days of age. It is concluded that EGF is restricted during postnatal development to the GCT cells, and that these cells and the distribution of EGF are represented dimorphically from their first appearance in the submandibular glands of both sexes.
A scanning electron microscopic study of the Sertoli cell and spermiation in the syrian hamster
Authors: Gravis Curtis J. 
Published: February 2005

AbstractThe scanning electron microscope was used to examine the Sertoli cells in normal and germ‐cell‐depleted testes. The Sertoli cells appear to attain characteristic configurations in the various stages of the cycle of the seminiferous epithelium. In tubules containing maturation‐phase spermatids, Stages I‐IV, the Sertoli cells exhibit column‐like bases which give rise to lamellae measuring 25–30 μm in width which ensheath the spermatids and residual cytoplasmic bodies. In the Stages VIII‐IX long flat sheets of Sertoli cytoplasm rest atop the step‐8 and ‐9 spermatids. These sheets are oriented parallel to the basement membrane of the tubule with their long axis parallel to the long axis of the tubule. In Stages V‐VI the head and proximal portion of the tail of the maturation‐phase spermatids are ensheathed in sleeve‐like Sertoli cell processes. Cuff‐like terminations demarcate the terminus of these sleeves that surround maturing spermatids up to spermiation. In tubules undergoing spermiation, the sleeves retract so that only the tip of the spermatid head remains in the sleeve. Appendicular processes extend from the dorsum of the Sertoli cell sleeves in the tubules undergoing spermiation. After spermiation the appendix elongates while the sleeve evaginates until the everted sleeve is a finger‐like process that extends into the tubular lumen. In tubules in which the seminiferous epithelium has been depleted with epinephrine injections the Sertoli cells attain two configurations. The first is characterized by having long attenuated lamellar processes that orient perpendicular to the basement membrane, with numerous ramifying processes arising from the lamellae. In the second configuration the Sertoli cells' lamellae orient parallel to the basement membrane of the tubule and lack the elaborate ramifications seen in the first configuration.
The annular hematoma of the shrew yolk‐sac placenta
Authors: King Barry F. , Enders Allen C. , Wimsatt William A. 
Published: February 2005

AbstractThe annular hematoma of the shrew, Blarina brevicauda, is a specialized portion of the yolk‐sac wall. In this study, we have examined the fine structure of the different cellular components of the annular hematoma. Small pieces of the gestation sacs from seven pregnant shrews were fixed in glutaraldehyde and osmium tetroxide and processed for transmission electron microscopy. In the area of the trophoblastic curtain, the maternal capillary endothelial cells were hypertrophied and syncytial trophoblast surrounded the capillaries. Cellular trophoblast covered part of the luminal surface of the curtain region, whereas masses of apparently degenerating syncytium were present on other areas of the surface. Maternal erythrocytes, released into the uterine lumen from the curtain region, were phagocytized and degraded by the columnar cells of the trophoblastic annulus. No evidence of iron or pigment accumulation was evident in the parietal endodermal cells underlying the annular trophoblast. Parietal endodermal cells were characterized by cuboidal shape, widely dilated intercellular spaces, and cytoplasm containing granular endoplasmic reticulum. Endodermal cells of the visceral yolk‐sac accumulated large numbers of electron‐dense granules as well as glycogen in their cytoplasm. Hemopoietic areas and vitelline capillaries were found subjacent to the visceral endoderm. The various portions of the yolk‐sac wall of Blarina appear to perform complementary functions which are probably important in maternal‐fetal iron transfer.
The ovoimplantation of Microcebus murinus miller (primates, lemuroidea, strepsirhini)
Authors: Strauss F. 
Published: February 2005

AbstractThe process of nidation of Microcebus murinus may be subdivided into several stages (preadhesion, apposition, attachment and invasion), as is indicated for protracted phases of preimplantation. Not until the apposition stage does the inner cell mass orient itself orthomesometrially, while concurrently a nidation plaque develops in the abembryonal trophoblast that overlies and resorbs the coalescent glands. During the subsequent adhesion stage, the paraembryonal, bilaminar omphalochorion becomes attached to the uterine epithelium, with focal resorption of the latter. In addition, chorionic vesicles begin to develop. In the meantime, the embryonic disc has lost its trophoblastic cover as a preliminary to the formation of the pleuramnion.The formation of a nidation plaque, together with the subsequent central implantation of Microcebus, suggests a close relationship to Loris tardigradus, characterizing the mode of implantation of Strepsirhini. The nidation plaque and its invasive capacity, giving rise to a syndesmochorial placental nucleus, provide a placentological link to Galago demidovii.
Immunocytochemical localization of thyroglobulin in the endostyle of the anadromous sea lamprey, Petromyzon marinus L.
Authors: Wright Glenda M. , Filosa M. F. , Youson J. H. 
Published: February 2005

AbstractThyroglobulin (TG) was localized in the endostyle of the anadromous sea lamprey, Petromyzon marinus L. by means of the unlabeled antibody peroxidase‐antiperoxidase immunocytochemical method. TG was found localized on the apical surface and within the cytoplasm of type 2c and 3 cells and in some type 5 cells. By identifying the cells of the endostyle immunocytochemically it may be possible to study more readily the events of endostylar transformation during metamorphosis.
The ultrastructure of the neonatal pig colon
Authors: Wooding F. B. P. , Smith M. W. , Craig H. 
Published: February 2005

AbstractThe neonatal pig colon has several unique structural and developmental features. At birth it has a variable population of epithelial cells which in their arrangement on villus‐like protrusions and in their capability for protein uptake into large preformed supranuclear vacuoles closely resemble neonatal ileal cells. Such villus‐like protrusions and vacuolated cells are not present in the 2‐day‐old piglet. On the first day after birth absorptive epithelial cells which lack supranuclear vacuoles transiently accumulate a large number of lipid droplets, each separated from the cytoplasm only by a proteolipid interface. None of the much smaller lipid droplets bounded by a unit membrane of the smooth endoplasmic reticulum and characteristic of normal small intestinal fat uptake were ever seen in these cells. Very few of the large lipid drops remain on the second day after birth.This initial capacity of the colon for protein and lipid uptake never reappears.The pattern of colonic amino acid transport also changes markedly in the first four days of independent life and this may be correlated with the observation that the absorptive cells at birth have microvilli which are twice the length of those on similar cells at and after two days old. These morphological results are discussed in terms of implied functional changes in the neonatal period.
Electron microscopic observations of vaginal development in untreated and neonatally estrogenized balb/c Crgl mice
Authors: Cunha Gerald R. , Lee Andrew K. , Lung Ben 
Published: February 2005

AbstractLight and electron microscopic examinations of developing Mullerian vaginae were performed on untreated and neonatally estrogenized mice 1 to 12 days old. Vaginae of 1‐day‐old mice have an undifferentiated, pseudostratified columnar epithelium which slowly differentiates in untreated mice into an apparently mucus‐secreting epithelium. By day 12 the rough endoplasmic reticulum (RER), Golgi, and secretion granules are poorly developed features of the apical epithelial cells. In contrast, the stromal cells develop prominent RER and Golgi zones which in part are involved in the synthesis and secretion of collagen, which accumulates in the intercellular spaces.The effect of estradiol on developing vaginal epithelium is observed after 24 hours of exposure as an increase in RER and the Golgi. Estradiol (E) accelerates the differentiation of mucus‐secreting apical epithelial cells, whose apices become filled with secretory granules, and also promotes the formation of a cornifying epithelium from the underlying basal cells. This latter process is associated with an increase in cellular proliferation, an increase in the occurrence of desmosomes and associated tonofilaments, and the development of extensive interdigitation of plasma membranes.In untreated and E‐treated mice, the vaginal epithelium is separated from the stroma by a continuous, intact basal lamina. Transport of basal laminar material appears to occur via the processes of endo‐ and/or exocytosis in adjacent epithelial and stromal cells.
Histology and ultrastructure of the pig parotid gland
Authors: Boshell Jerry L. , Wilborn Walter H. 
Published: February 2005

AbstractParotid glands of adult pigs were studied by light and electron microscopy. The parenchyma consists of acini, intercalated ducts, striated ducts, and excretory ducts.Acini had little affinity for periodic acid‐Schiff and were alcian blue‐negative at pH 2.6 or 0.5. These results indicate a paucity of neutral mucins and an absence of sialo‐ and sulfomucins. Histologically, acinar cells had vacuoles which corresponded ultrastructurally to large electron‐lucent secretory granules. The latter contained electron‐dense bodies and lipid droplets. Acinar cells differed histochemically and ultrastructurally from typical serous cells and were classified as special serous.Intercalated duct cells near acini contained electron‐dense secretory granules and numerous microfilaments. Cells in distal segments lacked secretory granules.Striated ducts were lined by two types of columnar epithelial cells, light cells and dark cells. Light cells were characterized by numerous infoldings of the basal plasma membrane, mitochondria between the infoldings, and electron‐lucent vesicles in the apical cytoplasm. The mitochondria contained tubular cristae. Dark cells were characterized by an abundance of microfilaments and numerous infranuclear processes which extended to the basement membrane.Excretory ducts, in addition to light and dark cells, also contained basal cells and goblet cells. Mitochondria in the light cells had flattened rather than tubular cristae.The pig parotid is a unique salivary gland and the most atypical mammalian parotid gland studied thus far. Mitochondria with tubular cristae and vacuolated special serous cells with lipid in the secretory granules are hallmarks of the pig parotid.
Development of type I cells of the rabbit subclavian glomera (aortic bodies): A light, fluorescence and electron microscopic study
Authors: Hansen John T. 
Published: February 2005

AbstractThe embryogenesis of the subclavian glomera (aortic bodies) is controversial. Past investigators have attributed the development of the Type I cells to mesodermal and/or neural elements. Based on the results of the present light microscopic, fluorescence histochemical and electron microscopic study of rabbit aortic bodies from 16 days of gestation (term: 31 days) to four days postpartum, it appears that the Type I glomus cells are derived from cells of neural crest origin. The subclavian glomus anlage is associated with cells of vagal origin throughout its development. Evidence of Type I cell development from pre‐existing mesodermal condensations is not observed. Type I cells exhibit formaldehyde‐induced‐fluorescence by the twentieth day of gestation. Dense‐cored cytoplasmic vesicles are apparent by the sixteenth day of gestation. The number of cytoplasmic vesicles increases steadily, but the greatest increase of vesicles is observed between the twenty‐eighth day of gestation and birth. Primitive Type I glomus cells exhibit abundant polysomes and rough endoplasmic reticulum indicative of synthetic activity. Nerve terminals are apparent adjacent to Type I cells by the twentieth day of gestation, but synaptogenesis does not occur until sometime between the twenty‐fourth and twentyeighth days of gestation. Abundant vascularity, characteristic of chemosensory glomera, is not achieved until the twenty‐eighth day of gestation.
Epidermal migration during the healing of suction blisters in rat skin: A scanning and transmission electron microscopic study
Authors: Pang Stephen C. , Daniels William H. , Buck Robert C. 
Published: February 2005

AbstractFluid‐filled blisters, created on the skin of the inner surface of the pinna of heparinized rats by the application of suction, showed an intact basal lamina through which protruded hairs and remnants of hair follicles. The origin of epithelial cells and their spreading over the basal lamina were studied at intervals over 36 hours using scanning and transmission electron microscopy. The majority of epidermal cells arose from the outer root sheath of hair follicles and began to spread radially before 12 hours. By 36 hours the cells were confluent over most of the blister base. Inflammatory cells were few in number and rested mainly on the bare basal lamina rather than on the resurfacing cells. Some elongated epidermal cells showing tapering foot processes appeared to be migrating in from the epidermis at the edge of the blisters. The cells spreading from hair follicles were flat and polygonal. On these sheets of cells a few small folds and many filopodia were present at intercellular junctions and at the free margin of the leading cells. Large numbers of short microvilli covered the surface of some of the epidermal cells, especially at 24 and 36 hours; other epidermal cells were relatively smooth.
Development of the dorsal cochlear nucleus of the cat: An electron microscopic study
Authors: Kane Eileen S. , Habib Christine P. 
Published: February 2005

AbstractThis developmental study of the dorsal cochlear nucleus (DCN) was based upon electron microscopic and Golgi preparations from many postnatal kittens (newborn‐4 months) and adult cats. Seven developmental stages were defined according to time of first alterations in size of layers, size, shape and packing of fusiform neurons; cytology of cytoplasmic organelles; cytology of fusiform cell layer (FCL) neuropil; and time when each of eight types of synaptic endings (defined in adults) appeared. During stage 1 (newborn‐2.5 days), fusiform and small cells were tightly packed. Fusiform cells, covered with multiform projections, were filled with large Golgi complexes and Nissl bodies. Free ribosomes were packed within invaginations of the nuclear envelope. The FCL expanded during stage 2 (3–6 days), both by growth of fusiform cells and by elaboration of FCL neuropil. Type 1 and type 5 endings appeared. During stage 3 (7–14 days), adult synaptic types 2, 2a, 3 and 4, plus a newly defined type 3a ending were found. Somatic projections decreased in number and length. This decrease continued into stage 4 (15–25 days), when synaptic type 1a appeared. Fusiform cells were separated by further growth of FCL neuropil during stage 5 (26–44 days). Adult synaptic type 5a was first noted during stage 6 (45–95 days), when glomeruli and synaptic nests were also identified. In the final stage 7 (120 days and older), glomeruli and nests matured, while maximally sized fusiform cells had smooth somatic membranes and nuclear envelopes. All adult synaptic types were mature after 120 postnatal days. This long interval for staged DCN development facilitates correlated developmental, electrophysiological studies. The latter might clarify functions of known inputs to DCN by matching maturation times of those inputs with appearance of specific physiological properties.
Postnatal development of the canine kidney: Quantitative and qualitative morphology
Authors: Eisenbrandt David L. , Phemister Robert D. 
Published: February 2005

AbstractThe normal postnatal development of the canine kidney was investigated utilizing qualitative and quantitative histologic methods. Kidneys were examined at 2, 4, 8, 14, 22, 70, and 200 days of age. A subcapsular nephrogenic zone was present in the kidneys until approximately eight days of age. This zone contained tissues which interacted to produce new nephrons and interstitial tissues. Several developmental stages of forming nephrons were identified in this zone. Beneath the nephrogenic zone, renal corpuscles of increasing maturity were located at successively deeper cortical levels. The total number of nephrons was estimated to be 445,000 per kidney. This number did not vary significantly during growth. The corpuscular volume per nephron increased 249% from 14 to 200 days of age. During the same period there was a 303% increase in the tubular volume per nephron. Although the developing kidney differed anatomically from the adult kidney, the individual nephrons maintained volumetric corpuscular‐tubular balance during growth.
Cytochemical localization of cations in the testis of the syrian hamster, utilizing potassium‐pyroantimonate
Authors: Gravis Curtis J. 
Published: February 2005

AbstractPyroantimonate has long been used as a cytochemical technique for the localization of cations. Although the technique was originally alleged to be specific for Na+, other cations, including Mg++, Ba++, Ca++, Zn++ and polycationic amines, form pyroantimonate precipitates. In seminiferous tubules treated with antimonate‐osmium fixation, the nuclei of the Sertoli cells and germ cells contained precipitates. In regions of condensed chromatin the precipitates were dense while, in dispersed chromatin, precipitates were sparse or absent. It is postulated that the dense precipitates observed in the condensed chromatin may represent an accumulation of calcium that may facilitate chromatin condensation. The Sertoli cell nucleolar apparatus contained light precipitates in the pars amorpha, moderate precipitates in the nucleolonema, and heavy precipitates in the perinucleolar heterochromatin bodies. The nuclei of the maturation‐phase spermatids lacked any precipitates. The perinuclear ring of the acrosome‐phase spermatids contained pyroantimonate deposits. In the maturation‐phase spermatids, staining occurred in the postacrosomal dense lamina, in the subacrosomal space between the perforatorium and the inner acrosomal membrane, and in the central mass of the residual bodies. Since the postacrosomal dense lamina is the portion of the spermatozoon that initially fuses with the ovum, it is postulated that its cationic properties in some way facilitate this fusion.
Cobalt iontophoresis of sensory nerves in the rat lung
Authors: El‐Bermani Al‐Walid I. , Chang Tien‐Lan 
Published: February 2005

AbstractBy iontophoretically introducing, first, cobalt and, subsequently, sulfide ions into the vagus nerve, it is possible to trace sensory nerves to their endings in the rat lung. Nerve fibers and terminals are found predominantly in the adventitia of the airways and blood vessels. Some nerves are found in the submucosa of the bronchi and bronchioles. Some are found in the cardiac muscle on the periphery of pulmonary veins, and a few nerves are seen to end among smooth muscles of the blood vessels and the airways. At least three types of nerve endings can be identified at the light microscopic level: (1) free nerve endings; (2) brush‐like endings; (3) knob‐like terminals.
A comparative radioautographic study of chondrocytic proliferation in nasal septal cartilage of the 5‐day‐old rat, rabbit, guinea pig and beagle
Authors: Searls James C. 
Published: February 2005

AbstractGrowth sites within the cartilaginous nasal septa of four different species of animals (5‐day‐old rats, rabbits, guinea pigs and beagles) were identified by monitoring cellular proliferation radioautographically. A statistical analysis (MANOVA) was employed. It showed that, of the six combinations compared (rat‐beagle, rat‐guinea pig, rat‐rabbit, beagle‐guinea pig, beagle‐rabbit, and guinea pig‐rabbit), in only one (beagle‐guinea pig) was there any similarity in growth pattern. The other five combinations all were significantly different. Since no particular areas emerged, with any consistency, as common growth sites within any of the four kinds of septa, it was concluded that the nasal septum might well play a passive role in midfacial growth, rather than an active role as previously thought.
Ultrastructural study of granules in the corpora lutea of several mammalian species
Authors: Gemmell R. , Stacy B. D. 
Published: February 2005

AbstractThe ultrastructure of the corpora lutea of the goat, cow, rabbit, pig and guinea pig have been examined at a stage when progesterone was being secreted by the luteal cells. Densely staining granules, 0.2 μm in diameter, are present within the luteal cells of all the species examined. Granules were detected in the extra‐cellular spaces of the corpora lutea of the goat, cow and pig, but not of the rabbit or guinea pig. The luteal cells of the various species have the same basic structure but differ in the amounts of lipid and forms of smooth endoplasmic reticulum present.A common mechanism of hormone secretion, in granule form, is postulated for all luteal cells.
Formation and fate of ethionine‐induced cytoplasmic crystalloids in rat parotid acinar cells
Authors: Oliver Constance , Auth Regina E. , Hand Arthur R. 
Published: February 2005

AbstractThe formation and fate of cytoplasmic crystalloids in rat parotid acinar cells were investigated during ethionine intoxication and recovery. By day 3 of ethionine treatment, acinar cells had numerous autophagic vacuoles containing recognizable secretory granules and fragments of rough endoplasmic reticulum. By day 5, immature crystalloids were present in many of the autophagic vacuoles, and as the crystalloids matured, a 7‐nm periodicity became apparent. Crystalloids were never observed in the Golgi saccules or in any other organelle associated with secretory granule formation. When ethionine treatment was stopped, the acinar cells rapidly returned to their normal morphology. The majority of the crystalloids and autophagic vacuoles were lost from the cells during the first two to three days of recovery. At this time annulate lamellae were present intracellularly, and macrophages, many contaning crystalloids, were associated with the basal surface of the acinar cells. These results indicate that the cytoplasmic crystalloids are formed in autophagic vacuoles, and do not represent an abnormal secretory product. Additionally, during recovery crystalloids may be removed from the acinar cells by interaction with macrophages. The sequence of autophagic vacuole formation, development of crystalloids, macrophage infiltration and phagocytosis of acinar cell debris appears to be a non‐specific response of the rat parotid gland to cellular injury occurring in a variety of experimental and pathological conditions.