bluuebunny/crossref_metadata_2025_split huggingface dataset:
Penetration of the basal lamina of the uterine luminal epithelium during implantation in the rat
Authors: Schlafke S. , Welsh A. O. , Enders A. C. 
Published: February 2005

AbstractDuring early stages of implantation in the rat, as in other species that form a hemochorial placenta, there is a progressive increase in intimacy between blastocyst and endometrium. After initial invasion of the uterine luminal epithelium by trophoblast cells and displacement of epithelial cells, the trophoblast comes to lie adjacent to the residual basal lamina of the displaced epithelium but does not penetrate it. After a pause at the basal lamina, this temporary barrier is breached. To study the interrelation of trophoblast, uterine epithelium, and decidual cells with the epithelial basal lamina during the time of penetration of the basal lamina, implantation sites collected on day 7 of pregnancy were oriented so that the implantation chamber could be sectioned either longitudinally or transversely. Neither trophoblast nor uterine epithelial cells have processes that extend through the basal lamina. However, flange‐like processes from the decidual cells penetrate the basal lamina and underlie both trophoblast and, more rarely, epithelium. Smaller folds of the surface of decidual cells partially surround bundles of collagen fibrils oriented parallel to the long axis of the implantation chamber. Initially the area of penetration of basal lamina by decidual cell processes is quite restricted; as implantation proceeds the basal lamina becomes displaced and is sometimes not discernibl, extracellular materials accumulate, and the relationships become more difficult to follow. It is concluded that the initial breaching of the basal lamina is an activity of the decidual cells, and that contact of basal lamina with trophoblast is not necessary to permit this penetration.
A study of the position of the mandibular foramen in the adult human mandible
Authors: Nicholson Michael L. 
Published: February 2005

AbstractEighty dry, adult human mandibles of East Indian ethnic origin and bilateral eruption of third molar teeth were examined to measure the location of the mandibular foramen. The position of the foramen was found to be variable. However, the foramen was predominantly located at the anteroposterior midpoint of the ramus halfway between the mandibular notch and the lower surface of the mandible and two thirds of the way down a line joining the coronoid process to the angle of the mandible. In the majority of the mandibles studied the foramen was located below the occlusal surfaces of the molar teeth. It is concluded that the marked variability in the position of the mandibular foramen may be responsible for an occasional failure to block the inferior alveolar nerve.
Cell differentiation in the retina of the mouse
Authors: Young Richard W. 
Published: February 2005

AbstractCell differentiation in the retina of the mouse during the postnatal period was studied by autoradiography. Animals were injected with 3H‐thymidine at ages extending from the day of birth through postnatal day 11. Six weeks later the distribution of labeled nuclei in the cells of the mature neural retina was analyzed to determine when these cells completed their final mitosis prior to differentiating. Central and peripheral zones were analyzed separately. Cell division ceases by 5–6 days in the center of the retina and by 11 days in the periphery. Among cells produced postnatally, 73% differentiate as rods, 20% as bipolar cells, 6% as Müller cells, and 1% as amacrine and ganglion cells. At all stages of embryogenesis, the differentiation of at least three and as many as six distinct types of specialized cells is initiated simultaneously within the ventricular cell population.
Variational anatomy of the deep femoral artery
Authors: Siddharth Padmanabhan , Smith Noel L. , Mason Robert A. , Giron Fabio 
Published: February 2005

AbstractThe deep femoral artery is frequently incorporated in vascular reconstructive procedures in the proximal leg. To study the branching variations of this artery, we dissected 100 legs and then classified the anatomical patterns. The deep femoral artery originates a median distance of 4.4 cm from the inguinal ligament.The origin of the lateral circumflex artery varied greatly. When it branched from the deep femoral, the origin of the lateral circumflex was 1.5 cm (median) from the origin of the deep femoral. The medial circumflex artery originated from the deep femoral in 63% of the specimens. It arose separately from the common femoral and more proximally in 26% of the specimens, branching an average of 2.15 cm (median) above the deep femoral origin. Familiarity with these variations is essential to the vascular surgeon and, therefore, we have included diagrams based on our study as a ready reference.
Long‐term consequences of cis‐platinum‐induced renal injury: A structural and functional study
Authors: Dobyan Dennis C. 
Published: February 2005

AbstractPrevious studies have shown that a single dose of the antitumor drug, cis‐platinum, causes renal cyst formation in rats 1–6 months after drug injection. This observation led to a further evaluation of the long‐term effects of cisplatinum on the kidney of the rat. Fisher 344 rats (N = 13) were given either a single intraperitoneal injection of cis‐platinum (6 mg/kg body weight) or saline (control) and 15 months later renal function and pathology were assessed. The glomerular filtration rate and urinary osmolality in the cis‐platinum‐treated rats at 15 months were significantly reduced compared to controls, 520 ± 59 μl/min/gm kidney weight versus 799 ± 100 (P < .05) and 871 ± 194 mOsm/kg H2O versus 1471 ± 162 (P < .05), respectively. Renal injury was less marked and of a more chronic type than to that originally described 6 months after cis‐platinum. Morphometric evaluation of renal injury revealed cis‐platinum‐treated rats had greater numbers of abnormal proximal tubules (atrophic or hyperplastic) when compared to control rats. Glomerular sclerosis and interstitial fibrosis were also more prevalent in the animals injected with cis‐platinum. In the inner stripe of the outer medulla, numerous markedly dilated tubules filled with hyaline casts and lined by simple squamous cells were present. To assess why cis‐platinum exerts a chronic effect on the kidney, total platinum levels were measured in different regions of the kidney as a function of time after drug injection. Platinum levels were significantly elevated in the cortex, outer and inner stripe regions, and in the inner medulla for as long as 1 month after cis‐platinum treatment. By 2 months, however, the values were no greater than controls. In summary, cis‐platinum exerts a significant long‐term chronic effect on the structure and function of the rat kidney.
Spaced serial section analysis of the avian muscle spindle
Authors: Hikida Robert S. 
Published: February 2005

AbstractMuscle spindle ultrastructure of the extensor digitorum communis of pigeons was studied using spaced serial sections. The intrafusal fibers extended well beyond the ensheathing capsule, after which they became disoriented and often fused with each other before terminating on the connective tissue of extrafusal fibers. Several extracapsular fibers contained macrofibrils which were about 0.1 μm in diameter and contained several dozen smaller (10 nm) subunits. Intrafusal fibers commonly formed close attachments with one another for short or extended (240 μm) lengths. A basal lamina was absent between regions of pairing, and a myosatellite cell lay at the border of the coupled region. Several fibers could be coupled together in a single cross section; fibers coupled together, separated, and either recoupled or became associated with other fibers along the length of a spindle.Profiles of sensory terminals and sensory satellite cells alternated to form a smooth‐contoured surface over most of the fiber cross section in the equatorial region. The sensory terminals contained many mitochondria, lysosomes, and clear and dense core microvesicles. Both the terminals and sensory satellite cells formed desmosomelike junctions with the intrafusal fiber. A crescentic collagen sheath covered that portion of the fiber cross section containing the sensory terminal‐satellite cell complex. Inner capsule cells surrounded the entire assembly in the equatorial region.The basal lamina thicknesses differed over the naked intrafusal fiber compared to that portion covered by the sensory terminal or sensory satellite cell. The thickness was more than doubled over the latter regions, indicating that the basal lamina over these areas was a product of the fused intrafusal fiber and sensory terminal and/or sensory satellite cell basal laminae. These are discussed in terms of intrafusal fiber degeneration and regeneration.
Electron microscopic immunocytochemical localization of glucagon and pancreatic polypeptide in rat pancreas: Characterization of a population of islet cells containing both peptides
Authors: Cheng Kaung Hue‐Lee 
Published: February 2005

AbstractThe distribution of glucagon and pancreatic polypeptide was studied immunocytochemically in rat pancreas at both light and electron microscopic levels. My earlier observation that these two peptides are distributed in three cell types—cells containing glucagon, cells containing pancreatic polypeptide, and cells containing both—was confirmed at the electron microscopic level. In the glucagon‐pancreatic polypeptide cells, the immunoreactivities of the two peptides were present in the same secretion granules. In addition, these glucagon and pancreatic polypeptide‐containing granules were morphologically distinct from glucagon granules but similar to pancreatic polypeptide granules and somatostatin granules.
Nuclear uptake of 1,25‐dihydroxyvitamin D3 in developing rodent teeth: An autoradiographic study
Authors: Kim Y. S. , Clark S. A. , Stumpf W. E. , DeLuca H. F. 
Published: February 2005

AbstractTarget cells for 1,25(OH)2 vitamin D3 metabolites are identified in developing rodent teeth by the use of thaw‐mount autoradiography. Following the injection of [26, 27‐3H]‐1,25(OH)2 vitamin D3 into 18‐day‐ and 20‐day‐old fetal rats and neonatal mice, nuclear concentration of radioactivity is found in different cell types. In incisors of both animal groups, strong nuclear labeling is present predominantly in pulp cells, while relatively weakly labeled cells are found in the layers of odontoblasts, ameloblasts, and stratum intermedium. In molars, nuclear labeling is absent in fetal rats, but is present in 2‐day‐old neonates in pulp cells and cells in the layers of stratum intermedium of the first molars, but not in the second molars. The absence of labeled pulp cells in the progenitor regions of incisors and in molars of 20‐day‐old fetal rats, and differential ontogenic appearance of labeled pulp cells in molars, indicates that there is a critical period of receptor emergence. The finding that labeled pulp cells exist in the regions of incisors and molars where secretory odontoblasts are present suggests that nuclear uptake of 1,25(OH)2 vitamin D3 is related to cell maturation and differentiation, and topographically related to the formation of dentin. The results further suggest that, in contrast to bone, the predominant effect of 1,25(OH)2 vitamin D3 is not on tooth cells which are directly involved in the formation of calcified tissue, i.e., ameloblasts and odontoblasts, but rather on supporting tissues such as pulp cells and stratum intermedium.
Mucosubstance histochemistry in control and acid‐stressed epidermis of brown bullhead catfish, lctalurus nebulosus (LeSueur)
Authors: Zuchelkowski Edwin M. , Pinkstaff Carlin A. , Hinton David E. 
Published: February 2005

AbstractGlycoprotein components of epidermal mucous cells in control (pH 6.8) and acid‐stressed (pH 5.8, 4.8, 4.0) brown bullhead catfish were studied by histochemical and autoradiographic methods. Following exposure to acid, increased numbers of epidermal mucous cells were noted in all tissue sites studied, particularry dorsal and ventral skin. Mucous cells of control fish and acid‐stressed (pH 5.8) fish contained a mixture of neutral and acidic mucosubsf ances, the latter including both sialomucins and sulfomucins, with sialomucins predominating. An apparent shift toward increased sulfomucin production was observed in skin from fish exposed to pH 4.8 and 4.0. In addition, autoradiographic studies using 35S showed increased labeling of mucous cells in acid‐exposed (pH 4.0) epidermis, offering further support for a shift toward sulfomucin production in acid‐stressed fish. Absence of appreciable sulfomucin production in younger fish (<1 year old) suggested that this shift may be partly age‐dependent. The functional significance of increased sulfomucin production in acid‐stressed epidermal mucous cells is uncertain but may be related to maintenance of ionic equilibrium.
Effects of sexual rest or sexual activity on the structure and function of the ventral prostate of the rat
Authors: Aumüller G. , Braun B. E. , Seitz J. , Müller T. , Heyns W. , Krieg M. 
Published: February 2005

AbstractPrevious studies have shown that sexual activity increases the weight of the accessory sex glands significantly, while the organ weights correlate inversely with the assayable androgen receptor concentrations in the prostate of sexually active versus sexually resting rats. In an effort to determine the structural basis of this phenomenon, the ventral prostates of adult rats kept with female rats for 4–6 months (HE‐rats) were compared to those kept in groups of 5 males in one cage (HO‐rats) for the same period. As an estimate of the secretory function of the gland the concentration of prostatic binding protein (PBP) was determined in prostatic cytosols using a highly specific ELISA. Catecholamines were measured by means of HPLC and subsequent electrochemical detection. Morphological studies included immunocytochemistry of PBP, visualization of adrenergic nerves, stereological analysis of stromal and glandular compartments of the prostate, and electron microscopy of the epithelium.The main findings were as follows: (1) The prostates of HE‐rats were 35% heavier than those of the HO‐rats. (2) The content in secretion was in the same range in both HE‐rats and HO‐rats (1.5 and 1.44 mg PBP per 1 mg DNA). (3) Immunocytochemistry and electron microscopy demonstrated a very homogeneous secretion within the glandular lumen of HO‐rats with a diminished amount of secretory material within the glandular cells.In HE‐rats the glandular lumina were clearly larger in diameter and intraluminal secretion was less homogeneously stained. The height of the epithelium was increased and the individual secretory cells contained several secretory granules. Within the prostatic stroma the profiles of adrenergic nerves were more numerous in HE‐rats, and a greater total amount of noradrenaline was present. At the fine structural level signs of enhanced membrane turnover, such as lysosomal structures, were prominent in prostatic epithelium of HE‐rats, while in HO‐rats mostly dense bodies were observed. The results indicate that sexual activity results in the functional adaption (activity hypertrophy) of the prostate as a result of nerve‐associated control of glandular activity.
Interstitial compartment pathology and spermatogenic disruption in testes from impotent diabetic men
Authors: Cameron Don F. , Murray Frederick T. , Drylie David D. 
Published: February 2005

AbstractStudies utilizing animal models of diabetes suggest that diabetic complications of impotence involve structural lesions in the testis as part of an overall defect in the pituitary‐testicular axis. In the present study testicular biopsies from ten oligospermic and/or impotent men with diabetes were evaluated by light and electron microscopy.One biopsy was judged normal. The remaining tissue showed variable testicular pathology ranging from minimally to grossly affected. Seminiferous tubules had decreased tubule diameters, hyalinized tubule walls, and occluded lumina owing either to epithelial encroachment or cellular debris and exfoliated round germ cells. Sertoli cells were vacuolated and showed a high degree of apical cell membrane redundancy and degeneration. Although Sertoli‐Sertoli cell junctional complexes appeared normal, Sertoli junctional specializations associated with spermatids were structurally abnormal or absent. All tubules were variably depleted of adluminal compartment germ cell types. The interstitial compartment was filled with a collagen‐rich extracellular matrix concentrated around small blood vessels and seminiferous tubule walls. Capillaries and lymphatic endothelia appeared structurally abnormal and compromised by the interstitial “matrix expansion.” Some Leydig cells contained a variable number of small to large lipid droplets, vacuoles, and secondary lysosomes.Results indicate the presence of tissue pathology in testes of impotent diabetic men. Discrete ultrastructural lesions in apical Sertoli cell cytoplasm are associated with spermatogenic disruption and morphological changes in the interstitial compartment suggest microvascular complications.
Histopathologic changes of uterus following gossypol treatment during early pregnancy in rats
Authors: Rikihisa Yasuko , Lin Young C. , Walton Amelia 
Published: February 2005

AbstractIntramuscular injections of gossypol acetic acid (25 mg in 10% EtOH/kg/day beginning on day 2 of diestrus) disrupted early pregnancy in rats as determined by light and electron microscopy. As in pregnant controls, in the uteri of treated rats increased glandular secretion, stromal hyperemia, and decidual tissue formation were noted at days 3–5 of pregnancy. At day 6, extreme hyperemia and stromal hemorrhage had occurred around well‐developed decidual tissue with foci of denuded mucosal surface. There was extravasation of blood into the uterine lumen, which was absent in controls. At days 5 and 6 of pregnancy, electron microscopy revealed shorter and fewer microvilli on the uterine glandular cells in the treated versus the control uterus. Luminal epithelial cells had not undergone the normal changes of pregnancy. These results imply that gossypol administered under our conditions neither prevented nor delayed implantation and formation of decidual tissue in the rat uterine endometrium but continuing development of the endometrium was disrupted at day 6 of pregnancy. This disruption of pregnancy may have resulted from a luteolytic action by gossypol that would not permit full structural differentiation in the rat uterus after implantation.
Nonrandom positioning of Golgi apparatus in pancreatic B cells
Authors: Lucocq John , Montesano Roberto 
Published: February 2005

AbstractThe Golgi apparatus has a polarized distribution in a variety of cell types, and in certain epithelia its intracellular position correlates with the direction of vectorial transport and release of secretory products. We have studied quantitatively the orientation of the Golgi apparatus in pancreatic islet B cells by examining its location with respect to the juxtacapillary face of the cell. This was done (a) at the light microscope level on semithin sections of osmium‐impregnated islets, and (b) at the ultrastructural level on thin sections of intact pancreas. The data obtained with both methods show that in pancreatic B cells the Golgi apparatus is preferentially located in the position opposite to the juxtacapillary face of the cell. These results suggest a structural polarization of B cells, which may be important for the coordinate function of islets of Langerhans.
Activation of osteoclasts and the repopulation of bone surfaces following hibernation in the bat, Myotis lucifugus
Authors: Doty Stephen B. , Nunez Eladio A. 
Published: February 2005

AbstractIn previous studies of the adult bat, Myotis lucifugus, bone loss that occurred during the hibernating period was attributed to osteocytic osteolysis, rather than osteoclastic activity. We have used histochemistry and light and electron microscopy to determine the functional state of the skeleton during the hibernating period. We find that during hibernation the marrow cavity of the long bones is filled with lipid deposits interspersed with vascular sinusoids containing mononuclear cells and red blood cells. The lipid deposits are found within fat cells and at extracellular sites. Hematopoietic cells are absent, osteoclasts are absent, and the bone surfaces are covered with quiescent bone‐lining cells. Osteocytes retain their structural integrity and maintain canalicular systems with the bone lining cells and with other osteocytes.During the arousal period, osteoclasts reappear on the bone surface, followed in time by increased numbers of osteoblast‐like cells. Perivascular cells undergo structural hypertrophy. Many mononuclear cells are now found in extravascular sites. The lipid content in the marrow is gradually reduced and replaced by hematopoietic cells. Each of these events occurs in a repeatable sequence that is related to the state of hibernation of Myotis lucifugus.
Use of the fluorochrome propidium lodide for the identification of Xenopus germ plasm during immunofluorescence studies
Authors: Smith R. C. , Neff A. W. 
Published: February 2005

AbstractAddition of 0.5 μg/ml of the red fluorescent dye propidium iodide to the penultimate wash of Xenopus early embryo serial sections during immunofluorescence studies causes germ plasm to fluoresce brightly. Germ plasm can be accurately and speedily identified in the serial sections. The use of this dye is a marked improvement over previous methods of germ plasm identification in unstained sections. Studies involving screening for germ‐plasm‐specific antibodies are greatly facilitated by staining germ plasm red with propidium iodide and searching for green colabelling by fluoresceinated antibodies.
Tetralogy of fallot produced in chick embryos by mechanical interference with cardiogenesis
Authors: Aranega A. , Egea Jose , Alvarez L. , Arteaga M. 
Published: February 2005

AbstractThe tetralogy of Fallot was produced experimentally in the chick embryo by altering the development of the conus and delaying the disappearance of the conoventricular groove. The experimental procedure used consisted of placing a ligature or cerclage around the proximal portion of the conus for 24 hr in embryos in Hamburger‐Hamilton stages 17–21, thus altering cardiac hemodynamics particularly in the clonal region. At the same time the conus was prevented from aquiring its normal position owing to the persistence of the conoventricular groove. As a result, the most frequently observed abnormality (50%) was a complex of anomalies similar to tetralogy of Fallot in man. Varying degrees of pulmonary stenosis were observed in 85% of the experimental cases either as the only defect or in association with other cardiac malformations.