bluuebunny/crossref_metadata_2025_split huggingface dataset:
The ultrastructure of Ruffini and Herbst corpuscles in the articular capsule of domestic pigeon
Authors: Halata Zdenek , Munger Bryce L. 
Published: February 2005

AbstractThe present study identifies two types of sensory nerve endings in the articular capsule of the shoulder joint of domestic pigeons: Ruffini corpuscles (spray‐like endings), and Herbst corpuscles. Ruffini corpuscles occur in the fibrous membrane of the articular capsule and consist of two to four branched cylindrical segments within a network of fascicles of collagen fibers. At the terminal ends of the cylinders the perineural sheaths of the capsule are deficient and surround the fascicles of collagen fibers. The axon terminals in each cylindrical segment of a Ruffini corpuscle repeatedly ramify, giving rise to delicate neurite profiles. These neurites and associated Schwann cells envelope small fascicles of collagen fibrils. Schwann cells cover only a part of the neurite profiles. The myelinated afferent axon enters the midregion of the cylinder and has a diameter of ∼3 μm. Herbst corpuscles are situated in the subsynovial connective tissue and in the transition zone between the fibrous membrane and the muscular fascia. They appear as elongated ovals in longitudinal section and round in cross section. Small corpuscles measure ∼5 μm × 200 μm in length and large ones ∼100 μm × 600 μm. Each has a myelinated afferent axon (diameter 2.5–7.5 μm) that terminates in one to three inner cores. The inner core contains the nonmyelinated receptor portion of the nerve fiber surrounded by numerous cytoplasmic lamellae, a subcapsular connective tissue space, and a perineural capsule of eight to 12 layers. Avian joint receptors are similar to those present in the skin of various birds and Ruffini corpuscles resemble in fine structure equivalent receptors in joint corpuscles of the domestic cat.
The distribution and mobility of anionic sites on the surface of human placental syncytial trophoblast
Authors: King Barry F. 
Published: February 2005

AbstractThe purpose of this study was to examine the distribution and mobility of anionic sites on the surface of fetal trophoblast in contact with maternal blood using polycationic ferritin (PCF) as a probe. Pieces of human placental villi were washed to remove maternal blood, and fresh, unfixed tissue was expose to PCF for varying times, concentrations, and temperatures to determine the effects on labeling patterns. The major findings were: (1) anionic sites were localized almost exclusively on the microvillous portion of the trophoblast surface; intermicrovillous regions of the surface, including the coated pits, were generally not labeled with PCF; (2) PCF binding was present as small clusters on the microvilli. This pattern was observed in tissue incubated 5–10 sec at 4°C and 23°C. The size of the cluster was increased with increased incubation time, suggesting some aggregation or patching can occur; (3) following the fomation of patches, the anionic sites showed no evidence of being cleared from the membrane by endocytosis during incubation subsequent to labeling; (4) the binding of PCF to the surface was reduced by pretreatment of the tissue with neuraminidase. Tissue fixed in glutaraldehyde prior to PCF exposure showed both clustered and more dispersed labeling. The results indicate that anionic sites on human trophoblast surface have a non‐random distribution and have restricted mobility on the surface. This may be indicative of a segregation of different membrane proteins and functions within different structural regions of the placental cell surface.
Morphology, histochemistry, and distribution of serotonin‐containing cells in tracheal epithelium of adult rabbit
Authors: Dey Richard D. , Echt Robert , Dinerstein Robert J. 
Published: February 2005

AbstractWe have investigated morphologic and histochemical characteristics of serotonin‐containing epithelial cells in tracheas from adult rabbits, using the Falck‐Hillarp freeze‐dried formaldehyde vapor technique. An intracellular formaldehyde‐induced fluorescent substance was identified as serotonin by microspectrofluorometric techniques. Fluorescence microscopy and subsequent histochemical staining of the same sections demonstrated that serotonin‐containing cells were argentaffin‐, argyrophil‐, and ferric ferricyanide‐positive. The serotonin‐containing epithelial cells were more numerous in ventral than in dorsal aspects of trachea. The number of detectable fluorescent cells was reduced after reserpine administration but was not affected by injecting the amine precursor L‐dihydroxyphenylalanine (L‐DOPA). The emission peak of the fluorophore was not significantly shifted after L‐DOPA injections. The cells may regulate tracheobronchial‐pulmonary function by releasing serotonin or other as yet unidentified biologically active substances.
Effects of varying chamber construction and embryo pre‐incubation age on survival and growth of chick embryos in shell‐less culture
Authors: Dunn Bruce E. , Fitzharris Timothy P. , Barnett Bobby D. 
Published: February 2005

AbstractShell‐less cultrure involves culturing chick embryos with associated yolk and albumen outside of the eggshell and shell membranes. The technique allows direct access to and continuous observation of cultured embryos almost to the time of hatching. The plastic wrap/culture tripod technique described in this paper allows normal embryonic growth and differentiation from 48 hours (in ovo pre‐incubation age) through at least 10 days of total incubation. As the duration of in ovo pre‐incubation is decreased below 36 hours, there is a concomitant increase in the percentage of grossly abnormal embryos associated with decreased survival and retarded growth and differentiation. Survival of embryos pre‐incubated for 72 hours through 13 and 18 days of total incubation is greater than 80% and 40%, respectively. The wrap/tripod technique allows substantially better survival and more normal development of cultured embryos than does the petri dish technique of Auerbach et al. (1974). Embryonic growth in 7.8‐cm‐diameter chambers is significantly greater than in either larger (10.6 cm) or smaller (5.2 cm) diameter chambers. Some gas exchange through the culture chamber walls appears necessary for optional embryonic survival and growth. Suspending egg contents in either Safeway® or Handi‐Wrap® plastic wrap (both of intermediate permeability) in 7.8‐cm tripods resulted in superior growth and/or survival compared to suspension in Silastic® sheeting (high permeability), Saran Wrap® (low permeability), glass dishes (nonpermeable), or glass dishes lined with an inner layer of Safeway® wrap(nonpermeable).
Tridimensional study of the deep cortex of the rat lymph node. II: Relation of deep cortex units to afferent lymphatic vessels
Authors: Bélisle C. , Sainte‐Marie G. 
Published: February 2005

AbstractRecently, we reported that the deep cortex of the rat lymph node is formed of semi‐rounded structures, the “deep cortex units,” contiguous to the peripheral cortex and bulging into the medulla. It was suggested that a unit represents an accumulation of lymphocytes centered on the opening of an afferent lymphatic vessel. To verify the proposal, we carried out a tridimensional analysis of serially sectioned rat nodes, fixed by perfusion and trimmed in such a way as to preserve their lymphatics. The tridimensional analysis revealed that a constant topographical relationship exists between the units and the openings of the afferent lymphatics. The results demonstrated that the topographical organization of the deep cortex of a rat node correlates with the distribution pattern of the opening(s) of its afferent lymphatic(s). The overall observations suggested the following explanation for the shape and topography of the units: factor(s) present in the lymph would spread in a radial manner from the opening(s) of an afferent lymphatic through the underlying cortex. The factor(s) would induce morphological modifications in the stimulated semi‐rounded area which, in turn, would provoke a local accumulation of circulating lymphocytes.
Development of seminal vesicles and coagulating glands in neonatal mice. I. The morphogenetic effects of various hormonal conditions
Authors: Lung Ben , Cunha Gerald R. 
Published: February 2005

AbstractSeminal vesicles (SV) and coagulating glands (CG) from neonatal mice 1‐ to 7‐days old were observed in whole mount preparations. Untreated, normal SV developed elaborate epithelial branches beginning on day 3 with secondary branches appearing on day 6. Castration (C), estradiol treatment (E), and castration combined with estradiol treatment (C + E) inhibited the morphogenesis of the epithelial branches. Untreated CG formed solid epithelial stalks that developed lateral epithelial buds on day 3 which attained a complex morphological pattern by day 7. Treatment groups (C, E, and C + E) displayed a pattern of retarded growth with few epithelial buds appearing even at day 7. The effects of castration on both SV and CG were reversed by the addition of testosterone. Short term in vitro culture of 1‐day‐old SV and CG glands in control medium or medium supplemented with estradiol did not exhibit visible growth. Culture of SV and CG glands with testosterone or a piece of testis showed pronounced development.
Four hormones in the pancreas of the lizard, Anolis carolinensis
Authors: Rhoten William B. , Hall Carl E. 
Published: February 2005

AbstractThe electron microscopic localization of insulin, glucagon, somatostatin, and pancreatic polypeptide (PP) in the pancreas of the iguanid lizard, Anolis carolinensis was studied by the unlabeled antibody peroxidase‐antiperoxidase immunocytochemical technique. Insulin, glucagon, and somatostatin were localized absolutely to those cells previously identified on the basis of the characteristics of their secretory granules as being β cells, α cell, and D cells, respectively. The secretory granule cores of the PP‐containing cells appeared to be ellipsoidal with a semi‐major axis of 450 nm and a semi‐minor axis of 365 nm. This previously unidentified cell type is named the F cell, in keeping with the localization of PP to the original F cell of the canine pancreas. Without immunocytochemical staining, the qualitative ultrastructural characteristics of the F cell secretory granules were inadequate to permit certain identification of the F cell, especially with regard to the D cell.
Comparative morphometry of the upper bronchial tree in six mammalian species
Authors: Schlesinger Richard B. , McFadden Lynn A. 
Published: February 2005

AbstractThe length, diameter, and angle of branching of all airways through the sixth level of branching below the trachea were measured on corrosion casts prepared from the lungs of two animals whose bronchial geometry has not previously been studied, namely the donkey and the rabbit. These measurements and morphometric data for the rat, hamster, dog, and human obtained from other sources were analyzed and compared. The cast prepared from human lungs exhibited an airway geometry that was clearly distinct from that shown by the nonhuman species. The human upper bronchial tree was the most symmetrical with respect to airway diameter and angle of branching. In all species studied, airway length was the most irregular parameter. The reasons for differences in branching geometry are not clearly understood. However, when attempting to determine whether a particular species may be used as a model for man in inhalation toxicology, and in the subsequent interpretation of animal data, an appreciation of differences in airway morphometry is essential.
Changes in rat palatal epithelium during neonatal growth
Authors: Hill M. W. 
Published: February 2005

AbstractThe epithelium of rat palatal mucosa was examined from 2 to 30 days after birth and changes in epithelial thickness, cellularity, average cell volume, mitotic activity and the turnover time of the nucleated cell layer were determined from histological sections. The mean epithelial thickness, which was 35.3 ± 1.5 μm at 2 days, remained constant for the first 9 days and then progressively increased, reaching 91.7 ± 1.7 μm by 30 days. This change in thickness was partly bought about by a doubling of the number of nucleated cells per mm2 of the surface, from 90.4 ± 2.81 × 103 to 187.63 × 5.654 × 103, and partly due to a change in the ratio of cells in the progenitor and maturing cell compartments, as assessed by the change in volume of an “average” epithelial cell. Mitotic activity also remained constant for the first 9 days and then increased, reaching levels five times greater than initial levels by 30 days. It is suggested that these changes are brought about by frictional stimulation associated with the initial intake of solid food as well as systemic influences related to general growth mechanisms.
Sequential events in the formation of collagen secretion granules with special reference to the development of segment‐long‐spacing‐like aggregates
Authors: Cho Moon‐Il , Garant Philias R. 
Published: February 2005

AbstractThe formation and maturation of collagen secretion granules in periodontal ligament (PDL) fibroblasts of young male Balb‐C mice were studied by electron microscopy and cytochemistry. The Golgi apparatus was composed of several dictyosomes, each consisting of a stack of five smooth‐walled cisternae. Each cisterna was connected at both ends to a dilated saccule. The cisternae, with their associated pairs of saccules, underwent progressive maturational changes from the immature to mature face of each dictyosome. The most immature saccules (type 1) were large, spherical, and filled with loosely arranged short filamentous structures. These saccules were continuous with the first and second Golgi cisternae (counting from the immature side). Golgi saccules type 2 were ellipsoidal, associated with the third and fourth cisternae, and contained parallel, elongate filaments. The most mature saccules, type 3, were more rectangular and connected by a short fifth cisterna. They contained aggregated filamentous material in the form of eight segment‐long‐spacing (SLS)‐like crystallites, one in the center and seven at the periphery, to form a basic secretory unit. As type 3 saccules matured, the interconnecting cisterna progressively shortened until the two saccules were nearly juxtaposed. At this time the shortened fifth cisterna split to give rise to two independent presecretory granules. By progressive condensation, presecretory granules matured into secretion granules that contained a densely packed SLS‐ like aggregate, within which individual crystallites were no longer discernable. Maturation of cisternae and saccules involved removal of membrane, apparently by the formation and detachment of coated vesicles. The staining reaction with silver methenamine and phosphotungstic acid increased over the procollagen as the saccules matured, indicating addition of carbohydrate moieties and possible crosslinkages. It is concluded that the formation and maturation of collagen secretion granules in PDL fibroblasts involves the packaging and further modification of eight SLS‐like crystallites, which are secreted as a basic unit.
Morphological organization and contractile properties of the wrist flexor muscles in the cat
Authors: Gonyea W. J. , Marushia S. A. , Dixon J. A. 
Published: February 2005

AbstractA comparison of the anatomy, fiber type profiles, and contractile properties of the wrist flexor muscles was undertaken in the cat. Isometric contractile characteristics were measured for each muscle. Three muscle fiber types, FG, FOG, and SO, were differentiated by staining cross sections of each muscle for ATPase, NADH diaphorase, SDH, and α‐GPD activities. The wrist flexor muscles ranged from less than 1% to 49% SO fiber content; with two of the five heads of the flexor digitorium profundus (FDP) having 1% or less SO fibers (FDP1—1.07%, FDP5—0.81%) and the humeral head of the flexor carpi ulnaris muscle (FCUh) having the greatest content of SO fibers. The mean contraction time (CT) plus one‐half relaxation time for an isometric twitch was correlated with the percentage of SO fibers and ranged from 40.5 to 111.8 ms. Except for the FCU (37 ms), the CT was less than 25 ms for the wrist flexor muscles. The uniarticular wrist flexor muscles, the flexor carpi radialis (FCR), and the FCU had the highest percentage of SO fibers and were more fatigue‐resistant that the multiarticular muscles. Considerable differences exist in muscle structure, fiber type proportions, and contractile properties between the FCR and FCU, which may be related to functional differences between the two sides of the wrist that may exist during the placement of the foot during locomotion.
Histochemical patterns of dehydrogenase activity in the development of free muscle grafts in the rat
Authors: Magon Davindra K. , Basson Marc D. , Carlson Bruce M. 
Published: February 2005

AbstractPatterns of activity of six dehydrogenase enzymes were studied histochemically in 42 free muscle grafts in the rat. Within hours, the surviving peripheral muscle fibers can be distinguished from the central ischemic muscle fibers. The surviving muscle fibers retain their characteristic pattern of staining throughout the post‐transplantation period. The central ischemic muscle fibers stain abnormally and by five or six days they lose their enzymatic activity. The zone of regeneration, between the surviving and the ischemic muscle fibers, initially shows little dehydrogenase activity, but as the regenerating muscle fibers mature, they develop first a homogeneous staining pattern and, later, differences in staining intensity among different types of muscle fibers.
Change in intramembranous particle distribution in epididymal spermatozoa of the boar
Authors: Suzuki Fumie 
Published: February 2005

AbstractMembranes of boar spermatozoa from different regions of the epididymis and after ejaculation were studied by the freeze‐fracture replica technique. The ordered pattern of the intramembranous particles of spermatozoan plasma membranes was different in the five arbitrary zones of the epididymis and in the semen. A distinctive ordered pattern was absent in zone 1, which is the proximal segment of the epididymis. In zone 2, paired parallel rows of the particles were present in the plasma membrane over the acrosomal region. This parallel arrangement was not present in zone 3 spermatozoa. Anterior to the posterior ring, cords formed by packed particles were apparent in zone 2 spermatozoa and reached their maximum prominence in zone 3, and persisted in zones 4 and 5 and in the semen. The plasma membrane over the marginal ridge of the acrosome had a hexagonal array of particles only in zones 4 and 5 spermatozoa. A similar pattern appeared on the post‐acrosomal region of spermatozoa in zone 5 and in the semen. The plasma membrane of the middle piece had a rectilinear arrangement of the particles in zone 2 spermatozoa in which the migration of the cytoplasmic droplet was complete. Rudiments of the rectilinear arrangement persisted in spermatozoa in zones 4 and 5 and in the semen. These changes are discussed in relation to sperm maturation in the epididymis. The acrosomal membrane had a hexagonal arrangement of particles in the equatorial segment. The marginal ridge of the outer acrosonal membrane had parallel rows of intramembranous particles. The organization of the acrosomal membrane particles did not change during the epididymal passage of boar spermatozoa.
Membrane dynamics in the parotid acinar cell during regranulation: A stereological study following isoprenaline‐induced secretion
Authors: Williams M. A. , Cope G. H. 
Published: February 2005

AbstractRecently weaned male rabbits were injected either with 150 μg/kg isoprenaline in saline containing 0.01 M ascorbic acid or simply with the drug vehicle. Groups of drug‐injected animals were killed at various time after injection. Parotid gland tissue samples from all animals were fixed, embedded and thin sectioned, and micrographs were prepared at standard magnification. Estimations of membrane areas of each membrane type in parotid acinar cells were made. It was found that in animals killed 2 hours after induced secretion apical area was larger than in controls. In animals killed at sucessively later times the apical area was progressively less. No elevation of any internal smooth membrane areas was ascertained at any sampling time, though the areas of rough endoplasmic reticulum in 2–12 hour samples were larger. It is suggested that excess apical membrane, though probably removed by interiorization, is afterwards disassembled inside the cell to create fresh macromolecular building units (protein molecules), perhaps after passing through the Golgi apparatus. This cryptic pool of building units can provide about 900 μm2 of secretion granule membrane per cell, the supply apparently being exhausted in the first eight hours after degranulation, whilst granule numbers are being increased. Thereafter, apparently, limited granule fusion occurs, so that ultimately the cellular complement of secretion granule membrane comes to enclose a greater volume of secretory product, though the average granule number per cell is smaller.
Cellular composition of the rostral pars distalis of the anterior pituitary gland of the alewife, Alosa pseudoharengus, during the spawning run
Authors: Betchaku Teiichi , Douglas W. W. 
Published: February 2005

AbstractThe rostral pars distalis of the anterior pituitary gland of the marine alewife, Alosa pseudoharengus, during its annual spawning run to fresh water was examined histologically. The rostral pars distalis is composed of many interconnecting follicles of various sizes. Contrary to earlier reports, the follicular epithelium contains not only prolactin (PRL) cells but corticotropic (ACTH) cells and thyrotropic (TSH) cells (in addition to two nonendocrine cell types). Basally all three endocrine cell types make direct contact with the basement membrane which separates the follicles from the neurohypophysial processes. Apically, however, only the prolactin cells, the largest of the three, protrude into the follicular lumen by means of the small ciliated apical protruberance. All other cellular elements are sealed from the follicular lumen by a layer of covering cells which have properties of transitional epithelial cells. In the follicular epithelium, the slender TSH cells are intercalated between the large conspicuous prolactin cells. The ACTH cells, the smallest of the three endocrine cells, lie in deep invaginations in the basal regions of the individual PRL cells in such a way that on cursory examination they can be mistaken for the nuclei of the latter. Only a small portion of the cellular surface of the ACTH cell escapes the enveloping prolactin cell to make contact with the basement membrane of the follicle. In teleosts, prolactin, ACTH, and TSH have all been implicated in the regulation of hydromineral metabolism and reproductive development. The intimate spatial relation between the three endocrine cells in the alewife rostral pars distalis thus raises the possibility of some functional interactions at the adenohypophysial level, perhaps as an adaptation of this anadromous teleost whose reproductive development and behavior is associated with large changes in ambient salinity. The functional significance of the follicular lumen is discussed together with possible sensory functions of the PRL cells.