bluuebunny/crossref_metadata_2025 huggingface dataset:
Prenatal Development of the Human Submandibular Gland
Authors: El-Mohandes Essam A. , Botros Kamal G. , Bondok Adel A.
Published: July 2008

The prenatal development of the human submandibular gland has been investigated in 26 fetuses from the 10th week of gestation to full term. At 10–12 weeks, the glandular elements (primitive ducts and acini) were immature and surrounded by a loose mesenchyme. The acinar cell population increased gradually till the age of 32 weeks, and the rate of increase was diminished thereafter. At 16 weeks, intercalated and striated ducts were distinguished and their number increased till the age of 32 weeks when their number seemed to be stabilized. The development of the granular convoluted tubule cells from the proximal segments of striated ducts occupied the later stages of development. They appeared around the age of 20 weeks and proceeded till full term. At birth, the gland appeared devoid of mucous acini and fat cells and the secretory end-pieces were of the serous type. During the second trimester, periodic acid-Schiff- and alcian blue-positive secretory materials appeared in the epithelial cells of both ducts and acini, and in their lumina. This secretory activity was transitory and disappeared around the age of 28 weeks.The possible function of these secretory products is discussed.
Circadian and Photoperiodic Correlation between the Number of Pineal Gland Synaptic Ribbons and Serum Melatonin Levels in the Rat
Authors: García Cimas , Soriano Martinez , Torner Ruiz
Published: July 2008

A study is made of the number of pineal gland synaptic ribbons in 35 maleWistar rats over a 24-hour period during the months of September and February, in correlation to the serum melatonin levels during the same periods and photophases.The results of the study confirm those reported by others authors and suggest that the synaptic ribbons may be the stimuli-transmitting organs facilitating pineal secretory function.
Morphological Significance of the Pectineal Ligament of the Eye
Authors: Costa-Vila J. , Barastegui C. , Ruano-Gil D.
Published: July 2008

We have studied the arrangement of the pectineal ligament or its equivalent, the uveal trabecula, in herbivores, carnivores, primates and humans. From our investigations, the pectineal ligament, the uveal trabecula and the so-called processes of the iris form a morphological unit that is made up of the tendinous fibres of the longitudinal portion of the ciliary muscle, that are inserted into the periphery of Descemet’s membrane and send out ahead prolongations that extend to the anterior face of the iris. The so-called processes of the iris cannot be considered as independent structures since they represent the innermost fibres of the trabecular or uveal meshwork; in some species these have a thicker appearance, an arrangement that can occasionally be found in the human eye.
Effects of Exogenous Heparin on the Vasculogenesis of the Chorioallantoic Membrane
Authors: Ribatti Domenico , Roncali Luisa , Nico Beatrice , Bertossi Mirella
Published: July 2008

On the basis of the well-known stimulating role played by heparin on blood vessel neoformation in the chorioallantoic membrane (CAM) demonstrated by means of slow-release polymers soaked in this substance and placed on CAMs, a new technique of introducing heparin directly into the allantoic sac is proposed. According to observations carried out in ovo and after fixation, morphological modifications are demonstrated in the developing vasculature of the heparin-treated CAMs which, compared with the control CAMs, show dilated and sinuous arterial and venous branches, denser and irregular capillary networks, and a high number of vascular primordia.The results, confirming that heparin is involved in angiogenesis, indicate the suitability of the technique and suggest that the effects of this substance could be enhanced by growth factors released by CAM tissues rapidly growing up from the 5th to the 7th incubation day.
Ultrastructural Study on the Origin of Rat Microglia Cells
Authors: Boya J. , Carbonell A.L. , Calvo J. , Borregón A.
Published: July 2008

An ultrastructural study of the origin of microglial cells has been performed in albino rat brains taken from 17-day-old embryos up to 35-day-old rats. Invasion of the nervous parenchyma by macrophagic cells which appear in mesodermal sources is described. Although the two main microglial sources are the meningeal membranes and the vascular adventitia, pericytes may also participate in the formation of microglial cells.
Development of the Subfornical Organ and Area postrema of the Male Albino Mouse.Karyometric Effect of Neonatal and Prepuberal Castration
Authors: Castañeyra-Perdomo Agustin , Pérez-Delgado Maria del Mar , González-Hernández Tomas , Ferres-Torres Romuald
Published: July 2008

We have studied the karyometric development of the nuclei of the ependymal cells and neurons of the subfornical organ and the area postrema in the male albino mouse from the 5th to the 190th postnatal day. We have found similar patterns of development in both although the area postrema showed more significant postnatal oscillations than those of the subfornical organ, suggesting a more intimate chronological relationship to gonadal development. We have furthermore analyzed the development in two experimental groups: in the one animals were castrated at birth, in the other, castration was made on the 20th postnatal day. We have found that neonatal castration produced a significant decrease of nuclear sizes; this was more evident in the subfornical organ than in the area postrema in earlier stages of development while the response was similar in both at peripuberal ages. The response to prepuberal castration was similar in both organs.
Marginal and Folliculo-Stellate Cells of the Pituitary Gland of the Rat
Authors: Sbarbati A. , Zancanaro C. , Cinti S. , Osculati E.
Published: July 2008

We examined non-granulated pituitary cells (folliculo-stellate cells and anterior and posterior marginal cells of the pituitary cleft) in lactating and virgin female rats by means of electron microscopy and morphometry. Ultrastructure and morphometric parameters of the cells lining the pituitary cleft were similar in the two groups of animals. On the contrary, folliculo-stellate cells showed a marked nucleocytoplasmic activation in lactating rats in the electron microscope, which was confirmed by morphometric measurements. These results are not consistent with the hypothesis that the three cell types share the same reactivity during pituitary hyperfunction and that they have a common function, as suggested by purely morphological studies in various endocrine conditions. We believe that quantitation of cell response during such stimuli could be useful to further elucidate this matter.
Partial Degeneration of Autonomic Nerves of the Heart of Methotrexate-Treated Guinea Pigs
Authors: Qayyum M.A. , Fatani J.A. , El-Badawi M.G.
Published: July 2008

In the present investigation partial degeneration of adrenergic and cholinergic nerves of the heart of guinea pigs following methotrexate treatment has been reported. No appreciable change was observed in the autonomic nerve fibres after 3 days of treatment. However, after prolonged treatment some nerve fibres showed signs of degeneration and a few adrenergic and cholinergic nerve fibres had disappeared.
Quantitative Aspects of Growth Hormone Cell Maturation in the Normal and Little Mutant Mouse
Authors: Wilson Doris B. , Wyatt Darlene P. , Gadler Richard M. , Baker Carol A.
Published: July 2008

Growth hormone (GH) cells were analyzed by means of ultrastructural morphometry in the pars distalis of pituitary glands from male adult and immature normal (C57BL) and homozygous little (lit/lit) mutant mice. Thin sections were exposed to anti-GH serum and processed immunocytochemically with the colloidal-gold technique. In the pars distalis of adult lit/lit mice, the mean volume density of GH cells/total tissue was 24% of the normal value, granules/GH cells was 58% of normal, and granules/total tissue was only 12% of normal. Deficits in all of these parameters likewise occurred in immature glands, though to a lesser extent than in the adults.The results indicate that the GH deficiency in this mutant reflects quantitative deficits in both the secretory granule content of GH cells, as well as the GH cell content of the gland, with the latter being the more severely affected.
Effects of Nicotine on the Fertility, Cytology and Life Span of Male Rats
Authors: Riesenfeld Alphonse , Oliva Heidi
Published: July 2008

Contrary to an earlier opinion that nicotine has no effect on the fertility of male animals or humans, the present experimental study using male inbred Fisher rats demonstrates that the reproductive capacity of the animals is greatly reduced when injected with nicotine, and that the effect is much greater in male than in female Fisher rats similarly injected with nicotine. This is in accord with some earlier histological and morphological studies which have shown that female rodents have a greater tolerance to nicotine than their male counterparts. It is also confirmed by the cytologic observations of the present study.These observations show that, similar to female rats, inflammatory processes, as evidenced by an increased number of lymphocytes and/or polymorphonuclear leukocytes, are responsible for the decrease in fertility. However, the cytological profile is profoundly different in the two sexes: virulent inflammatory conditions begin much earlier in male rats, they are more frequent and, whereas the condition is reversible in the female animal when nicotine treatment is discontinued, it is not in some male rats, and inflammatory conditions persist for the entire life as does infertility. However, the life span of nicotine-treated male rats is greater than in female nicotine-treated rats, although it is shorter in both sexes than in their respective controls; in some male nicotine-treated rats, the life span is greater not only than in their male controls but even than in their female counterparts. Possible explanations for this apparently paradoxical life-prolonging effect of nicotine treatment are reviewed, but the evidence is either conflicting or insufficiently established and requires further study.
Neuroanatomical Study of Galen’s Anastomosis (Nervus laryngeus) in the Dog
Authors: Henry C. , Cazals Y. , Gioux M. , Didier A. , Aran J.M. , Traissa L.
Published: July 2008

To further knowledge of the laryngeal nerves, the nerve fibers of Galen’s anastomosis were studied using two neuroanatomical methods, namely nerve degeneration and horseradish peroxidase labeling. It is demonstrated that the superior laryngeal nerve forms part of the tracheal and esophageal nervous system. The value of the results in relation to physiological laryngeal studies and to human laryngeal diseases is discussed.
Occurrence of Substance P-Like Immunoreactive Nerve Fibers in Krause Corpuscles of the Dog’s Tongue
Authors: Ichikawa Hiroyuki , Nishikawa Shinji , Wakisaka Satoshi , Matsuo Saburou , Takano Yoshiro , Akai Michio
Published: July 2008

Substance P-like immunoreactive (SPLI) nerve fibers were demonstrated in the Krause corpuscles of the dog’s tongue using the indirect immunofluorescence method and cholinesterase histochemistry. SPLI nerve fibers were often in contact with Krause end bulbs and occasionally entered them. From this result it was suggested that substance P might be involved in sensory mechanism of the Krause apparatus.
Effects of Daily Administration of Tetrahydrocannabinol on Rat Preovulatory Follicles
Authors: Zoller Lawrence C. , Carr Kenneth
Published: July 2008

Using morphometric techniques, we analyzed the effects of Δ9-tetrahydrocannabinol (THC) on the ultrastructure of rat preovulatory follicles. Rats were injected intraperitonally once daily with vehicle alone, or with vehicle plus THC on diestrus (D), metestrus (M) and diestrus (D), or on estrus (E), M and D. All animals were killed on proestrus. Nuclear, mitochondrial, lipid droplet and lysosomal volume density in the membrana granulosa were analyzed. There was no change in nuclear volume, but there were significantTHC-induced decreases in mitochondrial and lipid droplet volumes in the peripheral region of the granulosa. There were increases in dense-body volume in all regions of the granulosa from rats given THC either on D alone, or M and D. Dense-body volume returned to control levels in rats injected on E, M and D. It appears that THC can affect follicular ultrastructure and the effects change with the number of injections.
Scanning Electron Microscope Study of the Communications between the Anterior Chamber and the Sinus venosus Sclerae in Primates
Authors: Costa-Vila J , Ruano-Gil D.R.
Published: July 2008

We have studied the morphology of the anatomical structures that permit communication between the anterior chamber and the sinus venosus sclerae. Examination of the posterior or inner wall of this canal, represented by the sclerocorneal trabecula, in 15 species of primates and 5 adult humans, has enabled us to observe the existence of some small orifices or stomata that are the outermost part of the so-called Sondermann’s canals, which in our opinion are made by the successive confluence of the interstices worked in the interior of the sclerocorneal trabecula by means of contraction of the longitudinal portion of the ciliary muscle.
Presence of a Blastocyst and Mast Cell Depletion of the Mouse Uterus
Authors: Hore Amitabh , Mehrotra P.N.
Published: July 2008

The mast cell population has been studied during early decidualization of the mouse uterus. The number increases in early pregnancy until the attachment phase when a sharp depletion is noticed.This fall has been correlated with stimuli of maternal origin, but at the same time the presence of a blastocyst at the presumptive implantation sites seems to exert a significant effect on the depletion of mast cells. A relationship between the number of mast cells in the uterus and the physiological state of the organ has definitely been established [Harvey, 1964; Likar and Likar, 1964; Gibbons and Chang, 1972; Brandon and Evans, 1983]. The number of mast cells in the pregnant uterus is known to decrease around the time of implantation in the rat [Shelesnyak, 1960; De Feo, 1967; Brandon and Bibby, 1979]. Several workers believe that the mast cell population and histamine content decrease as a result of a rise in circulating estrogen [Westin, 1955; Gibbons and Chang, 1972; Spaziani, 1975]. In the present communication the possibility of a relationship between the decrease in mast cell population and the presence of a blastocyst, whose estrogenic role has been reported [Dickmann and Dey, 1973; Dickmann et al., 1975; Sengupta et al. 1977] in the uterine horn has been discussed.
Three-Dimensional SEM Study of Arteriovenous Anastomoses in the Dog’s Tongue Using Corrosive Resin Casts
Authors: Kishi Yoshiaki , So Seigyo , Harada Youhei , Takahashi Kazuto
Published: July 2008

Arteriovenous anastomoses (AVAs) participate in the regulation of blood flow. Although it has been speculated that AVAs in the dog’s tongue play a role in the regulation of the body temperature, no published work is available on the structural characteristics of AVAs in the dog’s tongue. The purpose of the present investigation was therefore to determine the frequency of AVAs and their structural characteristics by the fabrication of vascular corrosive resin casts and examination under a scanning electron microscope.This method permitted not only the visualization of the three-dimensional characteristics of AVAs, but also a clear differentiation between arterioles and venules. The total number of AVAs in the mucosal lamina propria of the dorsum of the left tongue half was 2,292. Several essential types such as S-shaped, hook-shaped, straight, bibranching and Y-shaped AVAs were observed, of which the S-shaped and similar types constituted the overwhelming majority; Y-shaped types have never been reported heretofore. This study also revealed that the locations where AVAs were most often distributed were, in descending order of frequency, the tip, the corpus and the root area of the tongue. This high frequency and strategic location of AVAs in the tongue strongly indicate that AVAs of the dog’s tongue participate in the thermal regulation.
Morphometric and Three-Dimensional Study of Platelets during Activation in the Rat
Authors: Riboni Laura , Ubaldo Ernestina , Núñez-Durán Harol
Published: July 2008

In vivo activation of platelets, produced by damaging an artery in the rat with ultrasound, was studied with the electron microscope. We performed both a three-dimensional reconstruction by thin serial sections and a morphometric study of the activation process. This is characterized by exocytosis of the content of granules, widening of tubules of the open canalicular system, and emission of pseudopodia. The three-dimensional reconstruction suggested that some extended pseudopodia adhere to the arterial intima, and confirmed former observations that a locomotor apparatus differentiates in platelets adhering to the arterial intima. We speculate that the contraction of some pseudopodia may pull the platelet body toward the arterial wall.The morphometric study revealed that during activation the volume of the open canalicular system volume increases and that of the dense granules decreases; all other compartments did not change.
Le corpus adiposum buccae (boule de Bichat)
Authors: Kahn J.L. , Sick H. , Laude M. , Koritké J.G.
Published: July 2008

Bichat’s fat-pad was examined using dissections of newborns and adults, and histological sections of embryos and fetuses. A main part or body with six extensions (masseteric, superficial temporal, deep temporal, pterygomandibular, sphenopalatine and inferior orbital) can be recognized.
Quantitative Study of Intimal Longitudinal Smooth Muscle in Human Small Mesenteric Arteries
Authors: Can N.D. , Faragher E.B. , Hasleton P.S.
Published: July 2008

The present paper examines the results of quantitative assessment of intimal longitudinal smooth muscle (ILSM) in small arteries from normal mesentery in man. 212 vessels from 24 patients who underwent colectomy for colorectal carcinoma were studied. The mean amount of ILSM in these vessels was found to be 1.42% (range 0.00–8.90%) of external vessel diameter. A statistically significant (p = 0.018) positive correlation was demonstrated between the mean amount of ILSM in vessels from any individual patient and the level of diastolic blood pressure. It is concluded that increased intravascular tension is one factor which influences the development of ILSM in human small mesenteric arteries.
Size Distribution of Neurosecretory Granules in the Supraoptic Nucleus and the Neurohypophysis of Water-Loaded, Normal and Water-Deprived Rats
Authors: Andersen Lars , Keiding Niels
Published: July 2008

The profiles of the neurosecretory granules were measured in the supraoptic nucleus and in axons, swellings and endings in the neurohypophysis. This was performed after the secretion of vasopressin had been fully suppressed by water load for 1.5, 2.5 and 24 h, after the secretion had been stimulated by water deprival for 72 h and in normal rats with water ad libitum. A finite-difference algorithm was used for unfolding the size distribution of neurosecretory granules from the observed profiles, and showed a clear grouping of the neurosecretory granules into 3 size groups: small, medium-sized and large granules. Estimates of the relative volumes of the granules from these 3 groups were combined with previous results. In the supraoptic nucleus, water deprival increased the total volumes of the small and medium-sized granules, and water load decreased the volumes of the medium-sized and especially the large granules. However, in the neurohypophysis, water deprival decreased and water load increased the volume densities of the small and medium-sized, but did not influence that of the large granules. The results indicate that the medium-sized granules are vasopressinergic and the large oxytocinergic. Moreover, the results are consistent with the hypothesis that the small contain another peptide.
Cholesterol-Rich Microdomains in Rat and Porcine Thyroid Membranes Involved in TSH-Induced Endocytotic Processes
Authors: Barrière H. , Chailley B. , Chambard M. , Selzner J.P. , Mauchamp J. , Gabrion J.
Published: July 2008

Filipin, a polyene antibiotic, was used to detect cholesterol in thyroid membranes in vivo and in culture duringTSH stimulation. We found that apical and basolateral plasma membranes were heterogeneously modified by filipin which induced abundant lesions in apical membranes, whereas Golgi apparatus, endoplasmic reticulum, nuclear membranes were unmodified. Small apical vesicles and colloid droplets were generally highly enriched in these complexes, suggesting a high cholesterol concentration in their membranes. Pseudopod membranes, known to be highly specialized domains in the apical plasma membrane, appeared enriched in cholesterol. Consequently, we suggest that an increased cholesterol content may be involved in the stabilization of thyroid membranes during endocytotic processes.
Scanning-Electron-Microscopic Study of the Dorsal Lingual Surface of the Squirrel Monkey
Authors: Iwasaki Shin-ichi , Miyata Ken , Kobayashi Kan
Published: July 2008

The structure of the lingual papillae and the ultrastructure of the surface of the lingual dorsal epithelial cells of squirrel monkeys were observed by scanning electron microscopy. Filiform papillae were distributed over the entire dorsal surface of the tongue, except for the radix zone. Fungiform papillae were scattered among these filiform papillae. In the middle of the posterior end of the lingual body, a single vallate papilla was located. Higher magnification of the lingual dorsal epithelium revealed that prominent microridges and elevated intercellular borders occurred widely in the basofrontal area of the filiform papillae, interpapillar area and lingual radix zone. On the surface of the upper part of the filiform papillae, fine pits and hollows were observed. Indistinct microridges were distributed over the surface of the fungiform papillae.
Electron Immunocytochemical Co-Localization of Prochymosin and Pepsinogen in Chief Cells, Mucous Neck Cells and Transitional Mucous Neck/Chief Cells of the Calf Fundic Glands
Authors: Yamada J. , Andrén A. , Kitamura N. , Yamashita T.
Published: July 2008

The electron immunocytochemical co-localization of prochymosin and pepsinogen in chief cells mucous neck cells and transitional mucous neck/chief cells of calf fundic glands was studied using specific antisera for prochymosin and pepsinogen with a protein A-gold method. Prochymosin and pepsinogen immunoreactivities were detected in the same secretory granules of the chief, mucous neck and transitional cells, simultaneously using small and large colloidal gold particles. In chief cells, both immunoreactivities were distributed uniformly over the same zymogen granules showing a round, large, homogeneous and electron-dense appearance. In mucous neck cells, both immunoreactivities were found exclusively on the same electron-dense core located eccentrically in the mucous granule showing light or moderate electron density. In transitional mucous neck/chief cells, electron-dense cores became larger in size and some granules were occupied by the electron-dense core without a halo between the core and the limiting membrane. Both immunoreactivities were found uniformly over the electron-dense core. The granules having no halo in the transitional cells could not be distinguished from the typical zymogen granules in the chief cells.
Scanning Electron Microscopy of Human Ocular Vascular Casts: The Submacular Choriocapillaris
Authors: Fryczkowski Andrzej W. , Sherman Mark D.
Published: July 2008

Vascular casts were prepared from ten human orbits removed at autopsy from patients with no previous history of vascular disease. The ages ranged from 7 months to 68 years. The time interval between death and injection of the orbit was always less than 12 h.The vascular casts were examined under scanning electron microscopy with particular attention to the submacular region. We present photomicrographs of common findings seen in each of our specimens, and discuss our results with respect to current models of the submacular angioarchitecture.
Scanning Electron Microscopic Study of the Capillary Loops in the Dermal Papillae
Authors: Umeda N. , Ikeda A.
Published: July 2008

The microvasculature of the skin of the hand of Japanese monkeys was examined by means of scanning electron microscopy of corrosion casts. The vasculature of all areas of the skin of the hand was examined and divided into three structures excluding the nail bed: (1) In the ball of the finger, the typical structure of the capillary loops was studied. Capillary loops were formed out of not just one capillary vessel but two or three vessels. Each capillary vessel arose and divided into several branches at the papilla, and they became descending limbs. After the loop passed a hairpin turn, the descending limbs were 1.5 times larger than the ascending limbs in the intrapapillary portion, and they became extrapapillary venules. The descending limbs connected with the postcapillary venules in the postpapillary portion and with the horizontal network. The postcapillary venules fused with each other (1–5 loops) to form the primary and secondary venous arcades. (2) In the thenar eminence, the capillary loops were a little lower, and their grooves were wider than in the ball of the finger. The characteristic structure in this area was the interpapillar capillary network. (3) In the lateral side of the finger, the number of capillary loops formed by the arterial capillary network of the subepidermal layer was smaller.The capillary loops here had the lowest height and a simple structure.
Proposed Role of Microfílaments in the Cell Reorientation That Accompanies Somite Formation in Xenopus
Authors: Burgess Ann M.C.
Published: July 2008

Somite formation involves a reorientation of the cells of the paraxial mesoderm but the underlying mechanism of this movement has never been demonstrated. The present investigation shows bundles of myofibril-like material in the ventrocranial corners of some of the paraxial mesoderm cells of Xenopus prior to reorientation and consequent somite formation.
Metabolic and Phagocytic Activities of the Mouse Retina after 6-Hydroxydopamine Treatment
Authors: Yew David T. , Li Winnie W.Y , Zhang D.R. , Luo Z.B.
Published: July 2008

The activities in mouse retinae were evaluated after 6-hydroxydopamine injection. A significant increase in labeled leucine uptake was evident in the photoreceptor layer. Latex uptake in the pigment epithelium showed no changes. Denervation of catecholaminergic terminals inside the retinae thus affected the metabolism of photoreceptors.
Ultrastructural Analysis of Lymph Node Innervation in the Rat
Authors: Novotny G.E.K.
Published: July 2008

The morphological analysis of nerves in axillary lymph nodes of the rat revealed the presence of two types of axon possessing either a more or a less electron-lucent matrix. The more electron-lucent axons enter the node finely myelinated, do not contain synaptic vesicles and quickly divide to form branches approaching the basement membranes of blood vessels, as well as cellular elements.They may be interpreted as sensory axons. The less electron-lucent axons are unmyelinated, and contain three distinct populations of synaptic vesicles.These may all be present in one axonal varicosity, so that the existence of cotransmitters is highly probable.
Effects of Starvation on the Parathyroid Glands in Golden Hamsters of Different Ages, with Special Reference to the Frequency of Lipid Droplets
Authors: Emura Shoichi , Shoumura Shizuko , Ishizaki Noriko , Yamahira Tomo , Ito Masaki , Isono Hideo
Published: July 2008

The frequency of lipid droplets in the parathyroid glands of young, adult and senile golden hamsters after starvation was investigated. In the parathyroid glands of the young and senile golden hamsters, the number of lipid droplets increased to reach a peak by 2 days, then decreased slowly by 5 days after starvation, and decreased rapidly after refeeding. In the glands of adult animals it increased to reach a peak by 5 days after starvation and decreased rapidly after refeeding.These findings suggest that in the fasting condition there is a relationship between the number of lipid droplets and aging.
Immunocytochemical Localization of Parathyroid Hormone in Hamster Parathyroid Gland
Authors: Shoumura Shizuko , Emura Shoichi , Ishizaki Noriko , Yamahira Tomo , Chen Huayue , Isono Hideo
Published: July 2008

The immunocytochemical localization of parathyroid hormone was examined in the hamster parathyroid gland by using the protein A-gold technique. Protein A-gold particles were concentratedover secretory granules, large secretory granules thought to be storage granules and Golgi vacuoles. No protein A-gold particles were detected over large vacuolar bodies and cisternae of the granular endoplasmic reticulum.
Quantitative and Morphometric Parameters Determining the Development of the Supraoptic Nucleus in the Albino Rat
Authors: Remacha Bentura , Camarero Lazcano
Published: July 2008

The principal part of the supraoptic nucleus (SON) of the rat presents specific developmental factors. The parameters selected for their evaluation were volume of the SON, neuronal number and neuronal density. White Wistar rats of the age of 18, 19, 20, 22 and 23 intrauterine days, 15 days and 1, 3, 6,12,18 and 30 months were chosen for this study. The rat brains were fixed, cut into 10-µm-thick sections and stained with hematoxylin-eosin.The different measurements were carried out with a semiautomatic IB AS I image analyzer. In all stages of the rat life an increase in volume and a decrease in neuronal density per surface unit could be observed, but there was a difference in the dynamics of these changes depending on the stage in which the parameters were determined. There were two periods in the life of the rat in which neuronal death was very significant. The first was between the embryonic and juvenile stage and the second between the adult and senile stage. The increase in the volume influences predominantly the value of neuronal density.
Light and Electron Microscopy of Fetal Rabbit Skin with Special Reference to the Role of Mesenchymal Cells in Epidermal Differentiation
Authors: Maruyama Takeshi , Yoshizuka Mitsuaki , Fujimoto Sunao
Published: July 2008

Fetal rabbit skin between 10 and 26 days of gestation was observed by light and electron microscopy. The present study indicates that rapid epidermal differentiation, including the epidermal downgrowths as primordia of the hair follicles, is induced by aggregation of mesenchymal cells associated with growing capillaries beneath the epidermis. In addition, the transformation of these mesenchymal cells to vasoformative cells for rapid capillary growth is further evidenced by this study. Glycogen-storing cells in the periderm are most numerous between 15 and 18 days of gestation, but disappear almost completely by 20 days when a capillary network develops beneath the epidermis.This may imply an active involvement of the periderm in glucose uptake from the amniotic fluid during early developmental stages of the skin.
Gibt es beim menschlichen Embryo ein Kloakenfenster?
Authors: Rohrbach M. , Rickenbacher J.
Published: July 2008

Three- and four-day-old chicken embryos show normally a defect in the epithelium of the cloacal wall. This defect is not seen in human embryos at a similar developmental stage. Its signification is unknown.
Combined Perfusion and Percolation of Embalmed Animal Bodies for Removing Formaldehyde
Authors: Siemiatkowski M. , Plöen L. , Björkman N.
Published: July 2008

Excess formaldehyde was extracted from embalmed animal cadavers by vascular perfusion or combined perfusion and percolation with 20% ethanol. The perfusion was undertaken through a carotid artery and the percolation through the serous body cavities for 1–2 h. Nineteen goats were perfused once and one goat and three cows were perfused and percolated twice a day for 3 days. The extracted cadavers were stored in 20% ethanol or in a freezer at –20°C.The mean value of the atmospheric concentration of formaldehyde after extraction was 0.27 ± 0.05 mg/m3 for goats and 0.39 ± 0.12 mg/m3 for cows.
Scanning-Electron-Microscopical Study of the Seminal Vesicle, Coagulating Gland, Ampullary Gland and Ventral Prostate in the Golden Hamster
Authors: Chow P.H.
Published: July 2008

A study of the internal surfaces of the seminal vesicle, coagulating gland, ampullary gland and ventral prostate of the golden hamster was carried out by scanning electron microscopy. The internal surface of each of these glands was found to display characteristic features in topography and in arrangements of the microvilli. The features are useful in the identification of these glandular tissues in situ.
Macromolecular Composition of the Sarcolemma and Endomysium in the Rat
Authors: Lehto Matti , Kvist Martti , Vieno Toini , Józsa László
Published: July 2008

The macromolecular composition of sarcolemma and endomysium was studied by classical staining methods for glycosaminoglycans and using immunological techniques for proteins. Both proteoglycans and glycosaminoglycans (heparan sulphate, dermatan sulphate, chondroitin sulphate) could be detected in the sarcolemma. Type IV and type Vcollagen and laminin were found exclusively in the sarcolemma and endomysium. Type I and type III collagen as well as fibronectin were detected both in the endomysium and perimysium.
Permeability of Regenerating and Atrophic Choriocapillaris in the Rabbit
Authors: Korte Gary E. , Cushin Susan , Delman Nina
Published: July 2008

When rabbits receive intravenous injections of sodium iodate, large expanses of the retinal pigment epithelium are destroyed. The adjacent capillary bed, the choriocapillaris, atrophies in response to the loss of the pigment epithelium and then regenerates. This provides a model of the permeability of regenerating and atrophic choriocapillaris, which we studied using intravenously injected horseradish peroxidase and catalase. Regenerating capillaries were permeable to peroxidase but not catalase. The permeability to peroxidase was probably due to endothelial fenestrations, since catalase (which is larger than peroxidase and does not penetrate endothelial fenestrae) was retarded at interendothelial junctional complexes, indicating that they were intact. Atrophic choriocapillaries were impermeable to catalase but displayed a heterogeneous permeability to peroxidase.This was correlated with the presence or absence of fenestrae; capillary profiles lacking fenestrae retained peroxidase in their lumina, whereas if fenestrae were present the tracer penetrated into the pericapillary space. The observations indicate that: (1) the permeability of the regenerating choriocapillaris is qualitatively similar to the mature choriocapillaris, and (2) the atrophic choriocapillaris undergoes changes in permeability that are primarily correlated with the loss of endothelial fenestrae. The observations provide a functional correlate – change in permeability – for structural changes in choriocapillaris endothelium (thickening, loss of fenestrae) in response to destruction of the retinal pigment epithelium, which has been postulated to exert a trophic effect on these capillaries.
Immunocytochemical Studies of Astrocytes following Injury to the Cerebral Cortex of the Rat
Authors: Singh Dyal N.P. , Mathew Chacko
Published: July 2008

The morphological change of cerebral cortex astrocytes from protoplasmic to glial fibrillary acidic protein (GFAP)-containing cells is induced by injury. Protoplasmic astrocytes that contain no detectable amount of GFAP become filled with GFAP and their processes extend to form the glial scar around the wound. It is hypothesized that this transformation is induced by cAMP and neurotransmitters released from damaged neuronal cells. A similar mechanism may be present in other brain regions following injury or disease.
Quantitative Morphometric Analyses of the Exercised Extensor Digitorum Longus Muscle of the Mouse
Authors: El-Rimawi A.S. , James N.T.
Published: July 2008

The metric properties of several important components of muscle, the capillaries, the myonuclei and also the cross-sectional areas of type I and type II fibres in the extensor digitorum longus muscle of the mouse have been studied using techniques appropriate for anisotropic tissues. Myonuclear volume density (Nv) was found to be increased by 70% whilst capillary length density (Lv) was increased by 50%. The results were analysed using multivariate statistical analysis (MANOVA) which is necessary for the multiple comparisons which inevitably occur in any morphometric investigation. The mitochondrial distribution within type I fibres was analysed using two-way ANOVA to study the effect of exercise on the mitochondrial contents of the inner, intermediate and outer zones of the muscle fibre. Significant differences in the mitochondrial content in the various zones were found. Exercise was found to increase mitochondrial contents in all three zones.
Anatomical Anomaly of Human Digastric Muscles
Authors: Michna Horst
Published: July 2008

In the submandibular region an anatomical anomaly of muscle arrangement was found. Between the left and right digastric muscles, asymmetric accessory digastric muscles were detected, which all arose from the mandible and were attached to the hyoid bone. Furthermore, the right anterior digastric muscle had an accessory belly. These anomalies of digastric muscles may be anatomical manifestations of a functional support of the mylohyoid muscle.
Collagen and Non-Collagenous Proteins in Different Mineralization Stages of Human Femur
Authors: Mbuyi-Muamba J.M. , Dequeker J. , Gevers G.
Published: July 2008

Mineralized tissues exhibit varying degrees of mineralization in different areas within the same bone. Using the technique of density gradient fractionation, bone powder from the diaphysis of human femur has been separated in different fractions corresponding to the degree of mineralization. Isolated bone fractions were analysed for their content in collagen and non-collagenous proteins. The results showed marked differences between compact and spongy bones, this latter containing higher proportions of little mineralized bone particles than the former (p < 0.01).The ethylenediaminetetra-acetic acid (EDTA) extractability and the bone matrix size decreased relative to the decrease in specific gravity of bone particles. Among the matrix components of different fractions, sialoprotein consistently increased with the increase in specific gravity while proteoglycan decreased in reverse manner to the increase in collagen. However, in the most mineralized fraction (specific gravity: 2.33 g/cm3), the proteoglycan amount increased while collagen decreased. In conclusion this study of bone maturation in human femur confirms the suitability of the technique of density gradient fractionation in the studies of bone matrix-mineral interactions. Apart from the fraction with the highest specific gravity, the analytical results obtained in fractions are similar to those observed in age-related bone changes, suggesting that the increase in mineralization degree of bone particles may be related to their age.
Ultrastructural Features of Skeletal Muscle in Mice after Physical Exercise: Its Relation to the Pathogenesis of Leucocyte Invasion
Authors: Michna Horst
Published: July 2008

This study was designed to elucidate which factor(s) trigger off the enhanced macrophage activity after strenuous physical exercise. For an understanding of the cause of this phenomenon we extended the study of the ultra-structural features of skeletal muscle after physical exercise to its possible relation to the pathogenesis of leucocyte invasion. Ultrastructural investigations revealed muscle damage, after a strenuous physical exercise.The pathogenesis of the detected autolytic alterations could be related to a local accumulation of lactate, to the ischemic compression syndrome, to an insufficient oxygen supply or to anatomical peculiarities. The greatest functional claim was that fibrillolytic degeneration was capable of being triggered off in the skeletal muscular structure, thereby initiating the release of filament fragments, whose peptides were capable of being depicted as chemotactic signals for leucocytes.The appearance of leucocytes in the muscular tissue suggests that the basic humoral immunity reactions control the cellular cooperation in the muscular tissue.
Substance-P-Like Immunoreactive Subepithelial Nerve Plexuses in the Labial Mucosa of the Mouse
Authors: Ichikawa Hiroyuki , Nishikawa Shinji , Wakisaka Satoshi , Matsuo Saburou , Takano Yoshiro , Akai Michio
Published: July 2008

Substance P (SP)-like immunoreactivity was examined in the lower labial mucosa of the mouse by using the whole-mount technique. The density and design of subepithelial nerve plexuses containing SP differed depending on portions of the lower labial mucosa.
The Cavum Septi Pellucidi: A Fifth Ventricle?
Authors: Alonso J.R. , Coveñas R. , Lara J. , Piñuela C. , Aijón J.
Published: July 2008

The morphological characteristics of the cavum septi pellucidi (CSP) in the rat are described. This structure is formed by a set of cavities generally located in the midline area of the septal region. Into the lumen of the cavities free cells rooted out from the CSP walls were observed. Several layers could be delimitated from the surface of the CSP to the most inner region consisting of connective cells and fibers, and astrocytes. However, no ependymal cells were visualized. According to the morphological data, the CSP wall could have a function of resistance against mechanical tensions that are produced in this brain region.The term ‘fifth ventricle’ for the CSP seems to be inappropriate.
Morphology and Distribution of Tanycytes in the Third Ventricle of the Adult Rat
Authors: Mathew T.C. , Singh D.N.P.
Published: July 2008

Light microscopy and semithin methacrylate sections were used to study the tanycytic projections and morphology in the floor of the third ventricle of the rat. The tanycytic cell soma was located in the ependyma. The luminal surface showed minute protrusions into the ventricular space and their basal processes projected across the width of the parenchyma of the infundibular region. During their course, tanycytic processes made contact with capillaries in the parenchyma and pial surface, suggesting that they might be involved in uptake and/or delivery mechanisms between the cerebrospinal fluid, hypothalamic cells and blood vessels.
Ultrastructure of Secretory Cells of Male Accessory Sex Glands of Golden Hamster (Mesocricetus auratus) and Effect of Melatonin
Authors: Chow P.H. , Pang S.F.
Published: July 2008

A systematic study of the fine structure of normal (control) and melatonin-treated accessory sex glands (ASG) of the adult male golden hamster has been carried out. Based on the appearance and the predominance of the different organelles, three categories can be identified.They are: (1) the seminal vesicle and ventral prostate, both with prominent Golgi complexes, conspicuous secretory granules and parallel arrays of granular endoplasmic reticulum with narrow cisternae; (2) the coagulating gland and dorsal prostate with cytoplasm dominated by very distended cisternae of granular endoplasmic reticulum and apical blebbing; (3) the ampullary gland featuring abundance of mitochondria and lipid droplets which discharge their contents by the apocrine mode of secretion. Eight weeks of melatonin injection (50 µg/animal), administered at the last phase of the light period, induces structural modification reflecting loss of functional activities or even cell deaths of the ASG secretory cells, thus confirming the suppressive effects of melatonin on reproductive structures of rodents.
Microvasculature of Normal and Involuted Mouse Thymus
Authors: Kato Seiji , Schoefl Guttal.I
Published: July 2008

The spatial arrangement of blood vessels in the thymus of normal and hydrocortisone-injected mice was studied by light and electron microscopy. The thymus is supplied by one thymic artery which branches into arterioles as it enters the parenchyma.These, in turn, feed capillary networks in the cortex and in the medulla. Cortical networks at the periphery of the lobule form loops which return blood to postcapillary venules at the corticomedullary junction and in the medulla. There is no subcapsular venous drainage. The overall distribution of blood vessels in the involuted thymus is essentially the same as in the normal thymus but the pattern becomes irregular and the vessels are tortuous. The endothelium of the postcapillary venules is flat and surrounded by a wide perivascular space containing many lymphocytes. This space is delimited by basal laminae, on the one side by that of the abluminal surface of the venular endothelium, on the other side by that of a thin, sheet-like epithelial layer formed by cytoplasmic processes of reticular cells. The perivascular space is in continuity with the surrounding interstitial space via gaps in its epithelial sheet. It does not form continuous longitudinal channels along the venules, but is interrupted by epithelial trabeculae.There is no obvious difference in structure between the postcapillary venules and their perivascular spaces of normal and those of involuted thymuses. Lymphocytes are intercalated in the venular endothelium, particularly in involuted glands. They are present in the perivascular space and in gaps of the outer epithelial sheet.These findings suggest that the postcapillary venules and the perivascular spaces may function as pathways for the migration of thymic lymphocytes into or out of the blood circulation.
Gross and Microscopic Anatomy of the Kidney of the West Indian Manatee, Trichechus manatus (Mammalia: Sirenia)
Authors: Hill Ashley , Reynolds, III John E.
Published: July 2008

Examination of the gross and microscopic anatomy of the kidney of the West Indian manatee, Trichechus mαnatus, revealed that: (1) the medulla is about 6 times thicker than the cortex; (2) juxtameduUary glomeruli have a mean diameter 1.3 times greater than that of cortical glomeruli; (3) juxtameduUary glomeruli have 1.7 times as much volume as cortical glomeruli; (4) there are about twice as many cortical glomeruli as juxtameduUary glomeruli per square millimeter of cortical tissue, and (5) the vasa recta are closely juxtaposed to the thin loops of Henle in the outer medulla. Many of these results suggest an enhanced urine-concentrating ability in this species.
Identification of Filaggrin in Hassall’s Corpuscle by Histochemical and Immunohistochemical Methods
Authors: Favre Anna
Published: July 2008

The Hassall’s corpuscles of man and other mammals have been deeply stained by a histochemical method that demonstrates bound histidine. We have employed a polyclonal anti-filaggrin antibody on thymus sections to verify whether this positivity was due to filaggrin and profilaggrin, its polymeric precursor, like in the skin. The immunohistochemical reaction has confirmed the presence of filaggrin in human Hassall’s corpuscles as well as in other species. Different patterns have been obtained for corpuscles at different developmental stages.
Histochemícal Alterations in the Adult Rat Brain after X-Ray Irradiation: Effects of O-(β-Hydroxyethyl)-Rutosides
Authors: Lehmann F.-M. , Lierse W. , Thiel H.-J.
Published: July 2008

X-ray-induced tissue damage in the brain of adult rats was investigated in the presence or absence of O-(β-hydroxyethyl)-rutosides (OHR; active agents of Venoruton®, Zyma-Blaes, München, FRG). Histochemical methods were used for the detection of glycogen (periodic acid-Schiff), acid mucopolysaccharides (Hale) and acid phosphatases (Gomori) by light microscopy. The tissue alterations were reduced after drug application in the dose range between 5 and 7.5 Gy (300 kV, 12 mA). Exposure of the animals to higher irradiation doses (10,20 Gy) led to an inversion of the drug effect, now exerting pronounced tissue injury. For a possible explanation we discuss the inhibitory influence of rutosides (e.g. OHR) on the glycolytic pathway. Hence, a vital energy source of brain tissue could be impaired by the drug after reaching a threshold of 10 Gy.