bluuebunny/crossref_metadata_2025_split huggingface dataset:
Carbohydrate cytochemistry of rhesus monkey tracheal submucosal glands
Authors: St. George Judith A. , Nishio Susan J. , Cranz Diane L. , Plopper Charles G. 
Published: February 2005

AbstractThis study was designed to characterize the ultrastructure and carbohydrate content of secretory cells in submucosal glands of rhesus monkey and to compare this information with that available for humans. The tracheas from five adult monkeys were fixed by airway infusion, processed, and embedded for both light and transmission electron microscopy. Histochemical stains including alcian blue–periodic acid–Schiff, dialyzed iron, and high‐iron diamine‐alcian blue were applied to serial glycol methacrylate sections. The cytochemical stains used included periodic acid‐thiocarbohydrazide–silver proteinate, high‐iron diamine, and low‐iron diamine. The glandular secretory cells were divided into four categories based on ultrastructure and location within the gland. Cells in the first category resembled the mucous cell of the surface epithelium and were located in ducts most proximal to the tracheal lumen. The second category consisted of cells that were located in distal ducts and contained large electron‐lucent granules. The granules in both of these cell groups contained material that was periodate‐reactive and sulfated. Cells of the third category contained granules that were either electron‐lucent or electron‐dense. These cells, which were difficult to characterize as either serous or mucous, were located in secretory tubules and acini and contained periodate‐reactive glyco‐conjugates that were either sulfated or nonsulfated. The last category consisted mainly of cells that contained electron‐dense granules that were lightly periodate‐reactive or a few that were unreactive with any of the cytochemical methods used here. We concluded from this study that 1) the submucosal glands of rhesus monkey contain secretory cells with a variety of morphologies; 2) the secretory cells, which in some cases are not easily identified as mucous or serous, contain material that is periodate‐reactive and sulfated, contain material that is periodate‐reactive only, or contain no carbohydrate as detected by the cytochemical methods used; and 3) the submucosal glands of rhesus monkey trachea resemble those described in human airways.
The Golgi complex of the early spermatid in guinea pig
Authors: Burgos M. H. , Gutiérrez L. S. 
Published: February 2005

AbstractAfter aldehyde‐tannic fixation, Zinc‐iodine‐osmium fixation, Phospho Tungstic acid‐chromium stain and two cytochemical reactions, the ultrastructure of the Golgi complex of early spermatids in the guinea pig reveals two different regions. One, close to the cell surface, involves endoplasmic reticulum (ER), intermediate vesicles, and Golgi outer cisternae and has membranes of uniform thickness and symmetrical trilaminar pattern, a strong ZIO precipitate, and an almost negligible cytochemical reaction to polysaccharides and cholesterol. The other region, close to the nucleus, exhibits thicker, sometimes asymmetric membranes, a polygonal network coating the thick cisterna, condensing vacuoles and areas of the acrosomal membrane, an intense reaction to polysaccharides and cholesterol, and packages of different densities in the condensing vacuoles and acrosome. This work also shows the coincidence of the cytochemical marker of cholesterol with the polygonal coating of clathrin in the condensing face of the Golgi.
Scanning electron microscope study of the developing microvasculature in the postnatal rat lung
Authors: Caduff J. H. , Fischer L. C. , Burri P. H. 
Published: February 2005

AbstractDuring postnatal growth the parenchymal septa of rat lung undergo an impressive restructuring. While immature septa are thick and contain two capillary layers, mature septa are slender and contain a single microvascular network. Using the Mercox® casting technique and scanning electron microscopy, we investigated the mode and the timing of the transformation of the pulmonary capillary bed. During the third postnatal week the parenchymal septa rapidly mature to match adult morphology. Even in adult lungs, however, remnants of the immature status are present: A capillary bilayer is regularly found at the base and the tip of the septa. Our observations support the concept that reduction of intervening tissue, partial fusion of the two capillary networks, and preferential growth lead to the mature vascular arrangement. The fact that true mature interalveolar septa show a denser capillary network than alveolar walls abutting onto pleura, bronchi, or larger vessels is consonant with the fusion theory. Towards the nonparenchyma, the capillary network surrounding every airspace had no counterpart to fuse with.From quantitative data it can be calculated that owing to lung growth, mesh size should increase more than four times between birth and adult age. The adult lung network, however, is denser than the one in young animals. This means that new meshes must be added during growth. We propose that small holes observed in sheet‐like regions of the microvascuiature enlarge to form new capillary meshes. With this mechanism of in‐itself or intussusceptional growth, sprouting of individual capillary segments to increase network size is no longer needed.
Cell types in the pineal gland of the horse: An ultrastructural and immunocytochemical study
Authors: Cozzi Bruno 
Published: February 2005

AbstractA combined ultrastructural and immunocytochemical study was performed on the pineal gland of the horse in order to identify the cell types present and describe their characteristics. Comparisons have been made with other mammals. Two main cell types are present: pinealocytes and glial cells. Pinealocytes display different degrees of electron density in the nucleus and the cytoplasm, yet no ultrastructural feature supports the idea of separate populations. Putative secretory materials are stored in vesicles related to the Golgi apparatus. A variety of electron‐dense bodies are present in the cytoplasm. Interstitial cells responding to anti‐GFAP (glial fibrillary acid protein) and anti‐vimentin antibodies, but not to anti‐neuronal 200‐kD protein antibodies, are located close to the perivascular spaces and connective septa. Morphological and immunocytochemical features support classifying them as astrocytes, probably protoplasmic. The presence of a cavity lined with pericytes, putatively a remnant of the embryonic lumen of the organ, is a consistent finding and may relate to the third ventricle.
Embryological development of human palmar, plantar, and digital flexion creases
Authors: Kimura Sumiko , Kitagawa Tadashi 
Published: February 2005

AbstractThe aim of this study is to document the prenatal stages of development of the flexion creases on the surfaces of the human palm, sole, and digits. We used 160 human fetuses, 6–20 weeks of gestational age, to observe the morphological features of the hand and foot, as well as the period and location of the appearance of the flexion creases. We found that most creases develop concurrently with the appearance of the fetal volar pads and the rest develop independently of them. Furthermore, with some exceptions, the creases seem to develop independently of the flexion movements of hand and foot.
Variation in human fungiform taste bud densities among regions and subjects
Authors: Miller Inglis J. 
Published: February 2005

AbstractTaste sensitivity is known to vary among regions of the tongue and between subjects. The distribution of taste buds on the human tongue is examined in this report to determine if interregional and intersubject variation of taste bud density might account for some of the variation in human taste sensitivity. The subjects were ten males, aged 22–80 years, who died from acute trauma or an acute cardiovascular episode. Specimens were obtained as anatomical gifts or from autopsy. A sample of tissue about 1 cm2 was taken from the tongue tip and midlateral region; frozen sections were prepared for light microscopy; and serial sections were examined by light microscopy to count the taste buds. The average taste bud (tb) density on the tongue tip was 116 tb/cm2 with a range from 3.6 to 514 among subjects. The number of gustatory papillae on the tip averaged 24.5 papillae/cm2 with a range from 2.4 to 80. Taste bud density in the midregion averaged 25.2 tb/ cm2 (range: 0–85.9), and the mean number of gustatory papillae was 8.25/cm2 (range: 0–28). The mean number of taste buds per papilla was 3.8 ± 2.2 (s.d.) on the tip and 2.6 ± 1.5 (s.d.) on the midregion. Subjects with the highest taste bud densities on the tip also had the highest densities in the midregion and the highest number of taste buds per papilla. Taste bud density was 4.6 times higher on the tip than the midregion, which probably accounts for some of the regional difference in taste sensitivity. The difference of more than 2 log units in taste bud density probably accounts for some differences in taste sensitivity among human subjects.
Distribution of intravenously injected cationized ferritin within developing glomerular basement membranes of newborn rat kidneys
Authors: Abrahamson Dale R. , Perry Elizabeth W. 
Published: February 2005

AbstractTo label heparan sulfate proteoglycans and other strong anions within glomerular basement membranes (GBM) during assembly, cationized ferritin (CF), with a narrow isoelectric range of 7.7 to 8.2, was intravenously injected into newborn rats. Kidneys were then fixed and processed for electron microscopy at intervals ranging from 1 to 72 h after CF injection. One hour after injection, CF bound extensively to the lamina rara interna and externa of developing GBM and mesangial matrix and to tubular basement membranes (TBM). In double basement membranes of early stage glomeruli, large amounts of CF were also seen in central areas between the endothelial and epithelial basement membranes. In maturing‐stage glomeruli, CF bound throughout interior regions of GBM outpockets projecting into the epithelial side of capillary walls as well as to the laminae rarae. Because in adult rats CF binds only to the laminae rarae, the abundant anionic sites seen here in newborns between double basement membranes and within GBM outpocket interiors may be subsequently neutralized or removed during the GBM assembly process. In addition to basement membranes, CF was also located intracellularly within endocytic vesicles and lysosomes of glomerular endothelial, mesangial, and epithelial cells 1 h postinjection. CF was also present in similar structures within the tubular epithelium. In contrast to these findings, CF was gradually lost from developing GBM 5, 15, and 24 h after injection and was essentially cleared from all GBM, mesangial matrices, and TBM after 48 h. Large CF aggregates were progressively accumulated within mesangial lysosomes, however. The transient binding of CF to GBM anionic sites seen here was most likely due to its endocytic removal by developing glomerular endothelial, mesangial, and epithelial cells. Anions in the circulation probably also competed effectively with the GBM and TBM for bound CF.
Rotation of the junction of the outflow tract and great arteries in the embryonic human heart
Authors: Lomonico M. Paul , Moore G. William , Hutchins Grover M. 
Published: February 2005

AbstractThe factors which give rise to the normal relationship between the great arteries and their respective ventricles are unknown. The developmental anatomy of this region was studied by using frontal, sagittal, or transverse serial histologic sections of 17 normal human embryos of Carnegie stages 15–19 from the Carnegie Embryological Collection. Distances and angles between major anatomic landmarks were determined by using computer reconstructions of the serially sectioned embryos, three‐dimensional analytic geometry, and Euclidean distance formulas. The findings show that between stages 15 and 19 there is a marked rotation of the axis of the semilunar valves: frontal 121° counterclockwise, sagittal 196° counterclockwise, and transverse 240° clockwise. Simultaneously the great arteries lengthen at a faster rate than the rest of the heart; and there is also an increase in the caliber and wall thickness of the great arteries. These results suggest that the changing rate of growth between the great arteries and the heart is necessary to align the great arteries, the semilunar valves, and the muscular outflow tract septum appropriately with respect to the interventricular septum. Reductions in the rate of growth of the great arteries relative to the heart could, by causing changes in the rotation of great arteries and outflow tract septum, have a role in the pathogenesis of cardiovascular malformations such as tetralogy of Fallot and transposition of the great arteries.
Further ultrastructural observations on the sperm head of the plains mouse, Pseudomys australis (Rodentia: Muridae)
Authors: Flaherty Sean P. 
Published: February 2005

AbstractUltrastructural and histochemical techniques have been utilized to study selected aspects of the fine structure of the three‐hooked sperm head of the plains mouse, Pseudomys australis. The peripheral layer of the two ventral hooks was found to consist of a continuation of the postacrosomal dense lamina. Parallel ridges connected the dense lamina and plasma membrane in the postacrosomal region and ventral hooks. Both these regions stained intensely with silver nitrate. The distribution of action filaments in the hooks was investigated using NBD‐phallacidin. Fluorescence was more intense in the apical regions of the ventral hooks, and two bands of fluorescence extended caudally from their base. It was also shown that the equatorial segment of the acrosome extended onto the dorsal hook. The structural features of the three hooks are discussed in relation to their possible functional significance.
Dorsal cerebral collaterals of stroke‐prone spontaneously hypertensive rats (SHRSP) and Wistar Kyoto rats (WKY)
Authors: Coyle Peter 
Published: February 2005

AbstractEarlier studies established that stroke‐prone spontaneously hypertensive rats (SHRSP) invariably infarct after middle cerebral artery (MCA) occlusion. Normotensive rats are usually protected from infarction after the occlusion. Objectives of this study were to characterize the anastomosing collaterals that may determine the different outcomes to MCA occlusion in SHRSP and Wistar Kyoto rats (WKY). Young (5–10 week) and old (40–69 week) rats of each sex were anesthetized, then administered papaverine to produce maximal vasodilatation of the cerebrovascular bed. Under control conditions latex was injected into the arterial tree to measure the internal diameter of branches of the anterior cerebral artery (ACA), the MCA, and the ACA‐MCA anastomosing collaterals. Large diameter ACA and MCA rami in old, but not young, SHRSP were significantly smaller in diameter than the respective ACA and MCA branches in old WKY. The number of ACA‐MCA anastomoses was the same for SHRSP and WKY. Mean internal diameter of the ACA‐MCA anastomoses was significantly (p < 0.0001) smaller in SHRSP than WKY in both age groups. There were significant negative correlations between age and (1) the internal diameter of the ACA‐MCA anastomoses in WKY but not SHRSP, and (2) the largest diameter ACA and MCA rami in SHRSP but not WKY. The findings suggest that vascular resistance of fully relaxed collaterals is greater in SHRSP than WKY, thereby compromising the dorsal collateral circulation before large diameter vessel changes occur that accompany the established form of hypertension.
Number of mitral cells and the bulb volume in the aging human olfactory bulb: A quantitative morphological study
Authors: Bhatnagar Kunwar P. , Kennedy Ray C. , Baron Georg , Greenberg Richard A. 
Published: February 2005

AbstractThe present study documents the morphological changes in the aging human olfactory bulb. Eight bulb pairs from white females between the ages of 25 and 102 years were used. The number of mitral cells in layers IV and III was determined for each bulb and corrected for spilt cell error. Counts were made on 10‐μm thick Nissl‐stained sections at 250‐μm intervals. The mean number of mitral cells per olfactory bulb at age 25 was estimated from linear regression to be 50,935; at age 60, 32,718; and at age 95, 14,501. The average loss over the time interval studied was 520 mitral cells per year.The volume of each bulb layer, except layer IV, was determined. The difference in the volume of each layer within individuals with age and the total volume with age was not significant (P < 0.11). The estimated mean bulb volume was found to be 50.02, 43.35, and 36.68 mm3 at ages 25, 60, and 95 years, respectively. The estimated reduction in bulb volume per year increase of age was 0.19 mm3. The ratio of mitral cells to bulb volume for layer III decreased by 19.4 units for every year increase in age. No significant difference was found between the left and the right bulbs in regard to the number of mitral cells and the bulb volume.Histologically, the glomerular layer thickness as well as the mitral cell size and concentration per unit area decreased with age. The intrabulbar anterior olfactory nucleus was discontinuous, highly variable in size, and presumably variable even in neuronal numbers.
Anomalous interconnection between flexor and extensor carpi radialis brevis tendons
Authors: Nakahashi Takahiro , Izumi Ryutaro 
Published: February 2005

AbstractA rare case of a short radiocarpal flexor (M. flexor carpi radialis brevis vel profundus of Wood) was found on the right forearm of a 47‐year‐old Japanese male corpse. The muscle arose from the anterior surface of the radius, ran distally in the deep layer of the flexor region to enter deeply into the carpal tunnel, and then interconnected with the subtendon of the extensor carpi radialis brevis at the gap between the bases of the second and third metacarpal bones. This muscle was supplied by a branch of the anterior interosseous nerve.
Occurrence of cells containing paracrystalloid material in the intestinal lamina propria of the hibernating bat Myotis lucifugus
Authors: Payette R. F. , Gershon T. R. , Gershon M. D. , Nunez E. A. 
Published: February 2005

AbstractA light and electron microscope study of the small intestine of the little brown bat, Myotis lucifugus, was carried out at several stages in the animal's annual life cycle. An unusual morphological observation was the presence of cells in the lamina propria of the small intestine which were packed with a conspicuous basophilic granular material that appeared crystalline. Moreover, such cells were present only during the hibernation period and were therefore called “hibernation crystalloid” (HC) cells. By light microscopy, the crystal‐like material was not sudanophilic, did not stain for nucleic acids, and did not contain acid phosphatase; it did show reactivity when stained by the periodic acid–Schiff procedure. By electron microscopy, the crystal‐like material was found to be present in smooth, membrane‐enclosed vacuoles along with an amorphous, dense granular substance. The crystal‐line material occasionally formed rigid‐appearing rods that reached lengths of 10 μm. The crystal‐containing cells were contacted by axonal varicosities. It is suggested that these innervated HC cells represent a unique cell type with a gastrointestinal function, yet to be determined, that may be related to hibernation.
Maintenance of adult rat ventral prostate in organ culture
Authors: Martikainen Paula 
Published: February 2005

AbstractAndrogens postpone the involution of prostatic tissue cultured in a chemically defined medium. However, after 1 week quantitative changes are accentuated and qualitative signs of involution appear. Other factors in addition to androgens are obviously needed for the adequate maintenance of the tissue. This study was aimed at the improvement of the culture conditions by adding insulin, corticosterone, epidermal growth factor, prolactin, and transferrin alone or in different combinations with testosterone and each other. A morphometric model developed for prostate culture was used, and maintenance and proliferation of the tissue were further followed by weighing the cultured explants and by measuring the incorporation of (3H) thymidine into DNA.The androgen dependency was seen in all the studied morphometric parameters at least for 2 weeks–i.e., in volume density and height of epithelium (VVEP and h), reflecting the epithelial maintenance, in volume density and width of interacinar tissue (VVIT and λAP), reflecting stromal tissue, and in volume density and diameter of lumen (VVLU and DLU), reflecting the secretory function. Testosterone (10−7 M) also prevented partially the quantitative involution of the tissue within 2 weeks.Insulin, acting independently of androgen, was a potent mitogen, which, according to morphometric results, exerted its effect mainly on prostatic epithelium. Stratification of epithelium was frequently seen. Corticosterone had no effect on epithelian proliferation, but it probably stimulated secretion and inhibited the growth of stroma.By combining these three hormones it was possible to maintain not only the structure but also the amounts of tissue components practically unaltered at least for 2 weeks.Epidermal growth factor (EGF) and prolactin had only marginal effects, and transferrin had none. It remains to be settled whether these three factors are needed for the prostate in long‐term cultures.
A scanning electron microscope survey of the origin of the primordial pronephric duct cells in the avian embryo
Authors: Jarzem Jacquelyn , Meier Stephen P. 
Published: February 2005

AbstractIn the avian embryo, the pronephric duct derives from the anterior part of a ridge that develops just lateral to the somites and segmental plate. The ridge extends from the sixth somite to Hensen's node and begins to form as the sixth somite is condensing. By the nine‐somite stage, the cranial end of the ridge (for a length roughly equivalent to four or five somite diameters) is seen as a duct primordium of smooth, elongated cells that resemble the migrating cells of the caudal tip of the duct as it extends to the cloaca. These cells show a decreased attachment to the fibers of the interstitial matrix and an increased adhesion to other duct cells. By 10 somites, there is a well‐formed pronephric duct rudiment at a time when the pronephric tubules have not yet begun to develop. Therefore, the avian pronephric duct has a separate origin from the pronephric tubules and may play an inductive role in the formation of pronephric tubules.