bluuebunny/crossref_metadata_2025 huggingface dataset:
Ultrastructural and Cytochemical Studies of the Fate of Unsecreted Collagen Precursors after Administration of Colchicine to Mice
Authors: Cho Moon-Il , Garant Philias R.
Published: July 2008

The administration of colchicine disrupts the normal organization of the Golgi complex and blocks the secretion of collagen precursors in periodontal ligament fibroblasts of the mouse. The fate of the unsecreted collagen precursors contained in Golgi-derived saccules and newly formed dense bodies was followed by electron microscopy. A progressive condensation of saccule content along with phase separation of electron-dense and electron-lucent material was observed. Fusion of saccules with dense secretory bodies gave rise to larger inclusions (zebra bodies; ZB) filled with a combination of electron-dense and electron-lucent material. In some ZB, these materials appeared to polymerize into fibrillar units. The fibrillar units stained with silver methenamine like normal collagenous fibrils. These results suggest that unsecreted collagen precursors accumulate in vesicular compartments within which partial polymerization can occur. This finding may explain some reports of intracellular collagenous fibrils in fibroblasts of pathologically altered connective tissues.
The Shifting of the Aortic Origin of the Brachial Arteries in the Metamorphosing Eel Anguilla anguilla (L.), with Remarks on the Shifting Mechanisms in Arterial Junctions in General
Authors: Willemse J.J. , Markus-Silvis L.
Published: July 2008

In silver eels the arteries supplying the pectoral girdles and fins, arise from a common trunk which branches off from the dorsal aspect of the dorsal aorta, while the origin of this trunk is found at the ventral aspect of the aorta in the leptocephalus larva. The rearrangement of the origin of this trunk is mainly accomplished during metamorphosis, and is related to the rearrangement of the junction of the epibranchial arteries and the aorta. The processes of remodelling the wall of the vessels involved in these rearrangements are discussed against the background of data on similar remodelling, accompanying the rearrangement of arterial junctions during the development of higher vertebrates.
Three-Dimensional and Surface Structures of Rat Filiform Papillae
Authors: Iida M. , Yoshioka I. , Muto H.
Published: July 2008

The three-dimensional and surface structures of the simple conical papillae of the rat tongue have been demonstrated with scanning electron microscopy. The papillary projection was organized into the anterior, posterior and central core cell populations, whereas the basal region of the papilla which consisted of circularly arranged cells showed no differentiation into three autonomic cell populations. It is considered that the anterior and posterior cell populations around the central core tend to be mutually attached at the bilateral sides, and that the posterior and core cell contacts are rather close than the anterior one. The anterior papillary cells showed relatively smooth surface with little micropits and without micro ridges. The reticular microridges on the basal cell surface of the posterior papillary cells appear to later develop the micropits and linear microridges on the tip cell surface. These suggest that the anterior cell surface is more highly keratinized than the posterior one. The microridges or micropits on the outer cell surface and the microprojections on the inner cell surface organizing filiform papilla are considered to be the structures for the purpose of cell adhesion.
New Views on the Identification of the Various Cell Types in the Pancreatic Islets of the Rat
Authors: Bani Sacchi Tatiana , Bani Daniele
Published: July 2008

Islets of Langerhans taken from different parts of the pancreas have been studied ultrastructurally in adult rats. Five different islet cell types were identified in each islet with the aid of morphometrical analysis of their specific secretory granules. Previous immunohistochemical findings concerning the amount and location of insulin-, glucagon-, somatostatin- and pancreatic-polypeptide-containing cells and their ultrastructurally recognizable counterparts were compared, and it was possible to identify four main islet cell types with the electron microscope. Moreover, cells quite similar to the enterochromaffine cells described elsewhere in the exocrine pancreas and in the gastrointestinal tract were found to normally occur in the pancreatic islets of the rat.
Influences of Joint Immobilization and Running Exercise on Articular Cartilage Surfaces of Young Rabbits
Authors: Jurvelin Jukka , Helminen Heikki J. , Lauritsalo Seppo , Kiviranta Ilkka , Säämänen Anna-Marja , Paukkonen Kari , Tammi Markku
Published: July 2008

The influences of joint immobilization and running exercise on the articular cartilage surfaces of the patella and lateral tibial condyle of young rabbits were investigated by the semiquantitative stereomicroscopic and scanning electron microscopic methods during a period of 8 weeks. The smoothness of the articular surfaces was disturbed already 1 week after the onset of immobilization. Leafy, slightly rough and rough surface qualities associated with superficial splits were observed. The changes were of the same nature after a longer period of immobilization. Running exercise on the treadmill (150–300 m twice a day, 12–24 min per turn, 5 times a week) led to an increase of the striated surface quality at 1 to-2-week intervals as compared with the controls. It was apparent that during immobilization remarkable changes of the articular cartilage took place within the first week, while running exercise up to 8 weeks elicited only transient or minor alterations of the articular surface.
The Oculomotor Nucleus, Not the Abducent, Innervates the Muscles Which Advance the Nictitating Membrane in Birds
Authors: Bravo Hermes , Inzunza Oscar
Published: July 2008

The topographic distribution of the neurones that innervate the muscles that advance the nictitating membrane in birds was studied using intra-axonal retrograde transport of horseradish peroxidase. The motor neurones are distributed in the oculomotor complex of the ipsilateral and contralateral sides. In the ipsilateral side, the neurones innervating the pyramidalis muscles were located in the dorsolateral, dorsomedial and ventromedial subnuclei, while those neurones innervating the quadratus muscle were found in the dorsomedial and dorsolateral subnuclei. In the contralateral side the neurones innervating both the pyramidalis and quadratus were distributed in the ventromedial and ventrolateral subnuclei. The sensory neurones were found in the trigeminal ganglion and trigeminal mesencephalic nucleus.
Scanning Electron Microscopic Studies of the Vasa vasorum of Thoracic Aortas
Authors: Song S.H. , Kratky R.G. , Roach Margot R.
Published: July 2008

Using hot alkaline solution, the elastic laminae were extracted from aortas and observed with scanning electron microscopy. Vascular structures were found in the elastin layers of the tunica media in descending thoracic aortas of sheep, dogs, and pigs, and these tube-like structures were filled with elastomer which was injected through the heart of the animal in vivo. Sub-intimal microvessels were also found to be filled with the elastomer and it is concluded that vasa vasorum can exist close to the internal elastic lamina in these animals.
The Origin of the Ectodermal Ring in Staged Human Embryos of the First 5 Weeks
Authors: O'Rahilly R. , Müller F.
Published: July 2008

Seven embryos of stages 10–16 (3–5 weeks) were studied for their external form by means of graphic reconstructions. This is the first systematic report on the general surface anatomy of the early human embryo. The brain has been described and illustrated in a previous publication, and the present article is concerned particularly with an important although neglected feature: the ectodermal ring, described by Schmitt [Morph. Arb., Jena 8: 236–303, 1898] and named by Blechschmidt [Funktionsentwicklung. I. Mechanische Genwirkungen. Muster-schmidt, Göttingen 1948]. Late in stage 10, three longitudinal bands can be seen on the surface: somitic, intermediate, and lateral plate. The intermediate band, which partly overlies nephrogenic tissue, is the site of the future ectodermal ring, which begins as an inverted U at stage 11 and is completed caudally in stage 12. The ectodermal ring, which may well be an important example of epithelial-mesenchymal interaction, comprises six parts: (a) rostral part, containing the situs neuroporicus, and olfactory and lens discs; (b) pharyngeal part, the covering of the pharyngeal arches; (c) occipital and cervicothoracic parts, related at first to the four occipital somites and later to the cervicothoracic junction; (d) membral part, represented by a preliminary ectodermal thickening, followed within 2 days by the apical ectodermal ridge; (e) intermembral part, related at first to the underlying coelom, and mesonephric duct and ridge; (f) caudal part, containing the cloacal membrane and a temporary ‘caudaf ectodermal ridge’. It is stressed that the incorrectly named ‘Milchstreifen’ is merely the intermembral part, in which the mammary crest (‘Milchlinie’ or ‘Milchleiste’) appears 1 week later.
The Attachments of the Lateral and Medial Ends of the Extensor Retinaculum of the Human Wrist
Authors: Salman S.S. , Ullah M.
Published: July 2008

The attachments of the lateral and medial ends of the extensor retinaculum of the human wrist were observed in 52 human upper limbs (from 26 cadavers) by dissection. In all the specimens used in this study, the lateral end of the retinaculum was found to be attached to the distal part of the anterior border of the radius and its medial end was attached to the styloid process of the ulna, the pisiform and the triquetrum.
The Adrenergic Innervation of the Guinea Pig Ovary During Prenatal and Postnatal Periods
Authors: Burden Hubert W. , Lawrence, Jr. Irvin E. , Louis T.M.
Published: July 2008

The pattern of adrenergic nerves was visualized and norepinephrine (NE) quantified in guinea pig ovaries from fetal day 50 to term and on days 1, 5, 10, 20 and 28 postnatally. Before birth, there were a few perivascular adrenergic nerves and correspondingly low ovarian NE levels. After birth and through day 20, nerves gradually grew into adjacent stroma. By day 28, there was a proliferation of beaded adrenergic nerves around blood vessels and into adjacent stroma, which was reflected by significantly increased ovarian levels of NE. These findings are discussed in relation to antral follicle development, atresia, and interstitial gland formation in the ovaries of prepubertal guinea pigs.
Craniofacial Growth in Patients with Craniosynostosis
Authors: Lavelle Christopher L.B.
Published: July 2008

With the growing appreciation that traditional cephalographic analyses provide data of dubious scientific validity, this study was undertaken to investigate craniofacial growth using the technique of biorthogonal analysis. This specific technique for the analysis of shape change showed relatively minor contrasts between control and craniosynostotic patients between 6 and 10 years of age. By contrast, marked variation was noted within component regions of the craniofacial skeletons in both patient samples: a feature not evident from traditional cephalographic analyses.
Structural Study on the Effect of 24,25-Dihydroxyvitamin D3 on Epiphyseal Growth Plate in Suckling Mice
Authors: Mirsky Nitsa , Silbermann Michael
Published: July 2008

The in vivo effects of 24,25(OH)2D3 on cellular structure and organization, matrix metachromasia and mineralization were studied in epiphyseal growth plate of normal neonatal mice. A relatively low dose of the metabolite, 40 ng/kg body weight, significantly increased the overall size of humeral growth plate and the zone of cellular proliferation. By and large, the tissue’s response to the metabolite did not change with the increase in dose administered except for a decrease in the number of chondroblasts. 24,25(OH)2D3 led to significant increases in the metachromatic reaction of the cartilaginous matrix, but appeared to depress the mineralization process. Qualitative structural changes were noted in chondroblasts and hypertrophic chondrocytes. 24,25(OH)2D3 affected the osteo-blastic and osteocytic populations of cells in the metaphysis and diaphysis of the humerus. High doses of 24,25(OH)2D3 brought about distinct atrophic changes in the above cells. These findings indicate that excessive doses of 24,25 (OH)2D3 in an intact animal may lead to retardative effects upon bone growth.
Influence of Fixative on the Fine Structure of Mouse Odontoblasts: A Study on Undemineralized Tissue
Authors: Andujar Mauricio B. , Magloire Henri , Couble Marie-Lise , Calle Aleth , Joffre Annick
Published: July 2008

The present report describes techniques of fixation and embedding suitable for studying the fine structure of odontoblasts without demineralization. The quality of the procedures employed was verified by comparing the ultrastructural preservation of the odontoblasts prepared by simple fixation and by the double-fixation method. Simple fixation by immersion in osmium tetroxide in vacuum preserves the longitudinal arrangement of the rough endoplasmic reticulum and Golgi apparatus, showing various vesicles which often contain filamentous threads of weak electron density aligned in parallel at repeating intervals typical of odontoblastic cells. The results obtained with this method are compared to previous descriptions of the ultrastructure of odontoblasts.
Effects of Progesterone on Nuclear Ribonucleoprotein Constituents of Endometrial Cells of the Rat
Authors: Echeverría Olga M. , Díaz Osuna Jorge , Hernández Irma , Sánchez Concepción , Parra Rosario , Hernández Rafael , Vázquez-Nin Gerardo H.
Published: July 2008

The effects of changes of progesterone concentration on 3H-uridine incorporation and on the volume or number of nuclear ribonucleoprotein particles of the rat endometrial epithelial cells are studied in vivo and in vitro. All progesterone treatments are carried out after estradiol priming and their results are compared with estradiol-treated controls sampled from the same uterus or the same pool of isolated cells. Progesterone induces the same changes, in the parameters studied, administered in vivo or in vitro. Nuclear volume undergoes small but significant increases between 1/2 and 8 h of treatment. The total number of extranucleolar ribonucleoprotein structures as well as the incorporation of 3H-uridine on non-nucleolar areas are also increased by progesterone treatments. However, the numerical density of perichromatin granules does not change during these experiments. The nucleolar volume and the incorporation of 3H-uridine in this structure are increased after an early diminution. These results indicate that progesterone induces small increases in the rate of transcription in the nucleolus and in non-nucleolar genes. The constancy of the density of perichromatin granules suggests that progesterone, in contrast to estradiol, does not affect the ratio transcription/transportation of RNA to the cytplasm.
Effects of Aminoglutethimide on Ovarian Histology in the Rat
Authors: Salih El Tayeb Y. , Pillay G.
Published: July 2008

Aminoglutethimide, a corticosteroid inhibitor, administered at a daily dose of 150 mg per kg body weight, showed a dramatic interference with ovarian histology in the rat. The drug caused thinning of the germinal epithelium and disruption of the layers of the follicular cells. It also resulted in the appearance of cytoplasmic vacuoles and distortion of follicle cell nuclei. In the corpus luteum, it caused shrinkage of the lutein cells, resulting in large spaces between the cords of cells. It also arrested immature follicles at various stages of their development. Our results indicate that aminoglutethimide, by modifying ovarian structure in the rat, interferes with the ovulation process.
Comparative Development of Thoracic Intervertebral Discs and Intra-Articular Ligaments in the Human, Monkey, Mouse, and Cat
Authors: Lohse C.L. , Hyde D.M. , Benson D.R.
Published: July 2008

Developmental features of thoracic intervertrebral discs and their association in the adult with other vertebral structures were investigated in four species. The human anulus fibrosus, nucleus pulposus, and intra-articular ligaments were compared to those of the fetal rhesus monkey, mouse, and kitten. Photomicrographs of transverse sections of intervertebral discs document the presence of intra-articular ligaments in fetuses of these four species. Both transverse and sagittal sections of kittens were used to identify the intercapital ligament as it differentiated from the dorsal part of the intra-articular ligament. Relatively frequent dorsal herniation of the thoracic nucleus pulposus in humans may be due to the vestigial nature of the human intra-articular ligament. Quadrupeds have well-developed intra-articular ligaments, which explains anatomically the paucity of dorsal protrusions of the nucleus pulposus into the vertebral canal in the thoracic region of the cat and mouse when compared to the human. The intra-articular ligament was closely associated with the developing prenatal mammalian intervertebral disc in the four species studied, and this relationship and its surgical importance are described.
Vasculogenesis in the Chick Embryo Optic Tectum
Authors: Roncali Luisa , Ribatti Domenico , Ambrosi Glauco
Published: July 2008

The initial formation and further development of the intraneural blood vessel network in the tectum opticum of the chick from the 4th to the 14th incubation day have been analyzed and some quantitative data morphometrically recorded. Vessels have been filled by intracardial injection of India ink in vivo. As inferred from our previous investigations on the vasculogenesis of several districts of the central and peripheral nervous system in the chick embryo, also in the developing optic tectum growth and distribution pattern of the vessels seem to unfold step by step under the local influence of earlier occurring morpho-histogenetic processes of the corresponding neural substratum.
Percentage of Projection Neurons and Various Types of Interneurons in the Human Claustrum
Authors: Spahn B. , Braak H.
Published: July 2008

Each neuronal type of the human claustrum is differently pigmented. This has been demonstrated by combining a transparent Golgi technique with the specific staining of lipofuscin deposits. One type of projection cells and four varieties of interneurons have been distinguished. In this study the percentage of these different neuronal types has been evaluated using preparations stained for both Nissl material and pigment deposits.
An Investigation of Potential Vascular Connections between the Kidney and the Adrenal Gland
Authors: Horacek M.J. , Earle A.M. , Gilmore J.P.
Published: July 2008

This study was conducted on two species of monkeys, Macaca fascicularis and Macaca mulatta, to determine if there were vascular connections between the kidney and other abdominal structures such as the adrenal glands. Microfil vascular perfusions, followed by microscopic observations and dissections, were utilized to investigate the existence of these potential connections. Highly anastomotic renal capsular vessels were always observed on the outer surface of the renal capsule. However, these capsular vessels did not make connections with the subcapsular capillary plexus in the majority of monkeys studied. Vascular connections between the adrenal gland and kidney were not observed. It was concluded that, although the region between the adrenal gland and kidney was rich in vasculature, it did not appear to play an anatomical role in anastomosing the extrarenal and intrarenal circulations.
Metabolism of Coronary Vasculature in Euthyroid, Hyperthyroid and Recovering Hyperthyroid Rats: A Histochemical Study
Authors: Cannon Samuel , Gelderd John B. , Kapes Evelyn D. , Wagner J.W.
Published: July 2008

Coronary arteries and arterioles from normal rats, from rats made hyperthyroid by administration of desiccated thyroid for 10 weeks, and from hyperthyroid rats which were then fed normal control diets for 10 weeks, were examined histochemically to determine the activity of key metabolic pathways. The primary aims of this study were to determine if the alterations in particular enzyme and substrate activities that occur in thyrotoxic rat myocardium, arteries and arterioles were reversible and would return to normal levels following cessation of the hyperthyroid state. Our results suggest that hyperthyroid rats, even after 10 weeks on the normal diet, still show some compromise in arteriolar aerobic metabolism in favor of anaerobic pathways, while coronary arteries still demonstrate little glucose-6-phosphate dehydrogenase activity. Myocardial metabolic activity approximates that of normal control animals by the end of the 10th week on the normal diet.
A Modified Silver Method for Demonstrating Developing Nervous Tissue in Culture
Authors: Spoerri P.E. , Ludwig H.C. , Ogawa Y.
Published: July 2008

Dissociated explants of 8-day-old embryonic chick cerebrum were cultured for up to 18 days. By the beginning of the 2nd week and thereafter, primary cultures of neurons exhibited characteristic differentiated morphology with an interconnecting neurofibrillary network that became increasingly ramified. Neurons in bipolar, tripolar or multipolar form could be demonstrated positively using a short modified silver impregnation method with potassium ferrocyanide.
Blood Vessel Size of Circulus arteriosus cerebri (Circle of Willis): A Statistical Research on 100 Human Subjects
Authors: Orlandini Giovanni E. , Ruggiero C. , Zecchi Orlandini S. , Gulisano M.
Published: July 2008

The brain weight of 100 fresh cadavers of Italian subjects (60 males and 40 females), aged between 17 and 84 years, was obtained and the corrected circumference of the following blood vessels was measured: basilar artery, internal carotid arteries, anterior and posterior cerebral arteries, and anterior and posterior communicating arteries. The cerebral ‘potential flow’ was expressed in each case by adding the circumference of the basilar artery to that of the internal carotid arteries. Moreover, the sides and the perimeter of the circle of Willis as well as the length of the basilar artery were calculated. The statistical analysis of the obtained data yielded the following main results: (1) the brain weight decreases with aging, is lower in females than in males and is statistically correlated neither with the circumferences of the considered arteries and the ‘potential flow’ nor with the perimeter of the arterial polygon (circle of Willis); (2) the arteries of the left side appear to be larger than those of the right one; (3) no significant difference exists in the circumference and length of the arteries between males and females; (4) the increase of the perimeter of the arterial polygon is achieved by means of a harmonious increase of all its sides; (5) the anterior and posterior communicating arteries have an anarchic pattern, because of the relatively frequent anomalies and the lack of a correlation between their circumference and that of the vessel of origin or of outlet.
Ultrastructure of the Neural Basal Lamina in Loop-Tail Mice
Authors: Wilson Doris B.
Published: July 2008

Ultrastructural features of the neural basal lamina were studied by means of the tannic acid and ruthenium red techniques in normal and abnormal dysraphic loop-tail mice at 9–11 days of gestation. With ruthenium red, the configuration of the neural basal lamina is similar in both normal and abnormal embryos at 9–11 days. However, differences were detected in the abnormal 9-day embryos processed with tannic acid, as compared with normal littermates. These include irregularities in the lamina rara externa, as well as differences in the staining pattern of the neuroepithelial cell plasma membrane. By 11 days of gestation, the lamina rara externa of the normal embryos shows features similar to those observed in the 9-day abnormal embryos.
The Epithelium of Uterine Biopsies from Cyclic Dairy Cattle: Ultrastructure and Endocytotic Activity
Authors: Hyttel Poul
Published: July 2008

An ultrastructural description of the epithelium of bovine uterine biopsies obtained during the oestrous cycle, implying lysosome characterization for acid phosphatase by incubation, was undertaken. By means of cationized ferritin (CF) experiments, it was determined whether apical vesicles in the non-ciliated surface epithelial cells were involved in endocytosis. The uterine surface epithelium as well as the glandular epithelium comprised ciliated cells and non-ciliated cells. The non-ciliated cell type performed a cyclic activity implying a higher occurrence of apical vesicles and greater size of the Golgi complexes at 7 and 14 days post-oestrum than at oestrus. This variation was pronounced in the glandular epithelium and less distinct in the surface epithelium. The apical vesicles in the non-ciliated surface epithelial cells were involved in endocytosis. The relative endocytotic activity, i.e., the proportion of CF-labelled structures, was low 7 days post-oestrum and high at oestrus. At the latter cycle stage CF particles were observed in apical vesicles, vacuoles, cisternal structures and bodies of similar morphology such as lysosomes showing reaction products after incubation for acid phosphatase. With increasing incubation time a shift in CF labelling from apical vesicles to lysosomes was noticed.
Anatomische Unterscheidung und klinische Bedeutung zweier verschiedener Anteile des Musculus vastus medialis
Authors: Scharf W. , Weinstabl R. , Orthner E.
Published: July 2008

In 32 corpses, either fresh or fixed, the deviations of the two heads (musculus vastus medialis longus and musculus vastus medialis obliquus) of the vastus medialis muscle from the long axis of the femur were measured. The deviations were between 15 and 18 degrees medially for the m. vastus medialis longus and between 46 and 52 degrees medially for the m. vastus medialis obliquus. Anatomical dissections of the vastus medialis muscle in 115 fixed thigh specimens could always demonstrate a clear separation between a long head of the muscle that inserts at the base (m. vastus medialis longus) and a short head (m. vastus medialis obliquus) that inserts at the medial margin of the patella. The plane of separation could be identified by a femoral nerve’s branch in every case. In 17 instances the nerve’s localization was superficial, in 57 in an areolar fascial plane, and in the depth between the muscles in 41 instances. The ramification of the femoral nerve’s branch that runs along the separation plane showed four types of variation. With these investigations it was possible to distinguish between two individual heads of the vastus medialis muscle not only with regard to its function, but also to its anatomy.
Differential Distribution of Immunohistochemically Detected Keratin Proteins in Mammalian Oral Epithelia
Authors: Hosaka Matsuji , Murase Noriyasu , Fukui Shin , Mori Masahiko
Published: July 2008

Keratin proteins were immunohistochemically demonstrated in different parts of the oral epithelium. Keratin staining in the squamous-cell epithelium was restricted to the spinous and granular cell layers, with a comparatively low reaction in the basal layer cells and none in the superficial cornified layer. In comparing the keratin staining levels, those in the buccal and sublingual epithelia were rather higher than those in the hard palatal epithelia. Staining intensities for keratin proteins were not the same in either different locations of the oral epithelium or in the same location in different animals.
Development of Otoconia in the Embryonic Chick (Gallus domesticus)
Authors: Fermin Cesar D. , Igarashi Makoto
Published: July 2008

In the chick (Gallus domesticus) embryo, otoconium formation started first over the macula sacculi around the 4th day of incubation, and a day later-over the macula utriculi. It was determined that each otoconium formed as a result of the segmentation of the immature otolithic membrane, and that the calcium responsible for otoconium calcification was incorporated into the organic matrix of each otoconium in the form of small electron-dense granules (20–150 nm in diameter). The presence of calcium in these granules was confirmed by histochemical staining with osmic-potassium pyroantimonate, by EDTA chelation, and by X-ray microanalysis under the electron microscope.
Structural Changes in Rat Hepatocytes following Ingestion of Sugar Solutions
Authors: Gottschall Elaine G. , McMillan Donald B.
Published: July 2008

The present investigation describes the structural changes in rat hepatocytes following the ingestion of 3% solutions of the dietary sugars sucrose, fructose, fructose/glucose, or glucose. The most striking changes occurred in rats that drank large amounts of sucrose where large areas of rarefied hyaloplasm isolated islands of cellular organelles. Similar but less dramatic effects were seen in hepatocytes of animals that drank moderate amounts of sucrose, fructose, or a combination of glucose and fructose. In contrast, the hepatocytes of animals that drank the 3% glucose solution did not display the rarefied hyaloplasm or disorientation of cellular organelles and resembled the hepatocytes of control animals. It is proposed that ingestion of large amounts of fructose results in a build-up of fructose-1-phosphate in the liver, thereby disturbing the osmotic equilibrium of hepatocytes and causing the structural changes noted.
Mitotic Activity and Its 24-Hour Rhythm in the Ovarian Follicles during the Estrous Cycle of a Wild Rat, Bandicota bengalensis
Authors: Sahu Abhiram
Published: July 2008

Mitotic activity in ovarian follicles was studied in relation to the size of the follicles during a 24-hour period (10.00, 16.00, 22.00 and 04.00 h) throughout the estrous cycle of the wild bandicoot rat (Bandicota bengalensis) to ascertain the cell proliferation rate and its 24-hour rhythm in the follicular tissue. In the bandicoot ovary, mitotic activity in the granulosa and thecal cells was highest in the follicles ranging from 201 to 400 µm in diameter. During the estrous cycle, mitotic activity of the granulosa cells was highest at estrus in follicles < 601 µm, and at diestrus in follicles > 600 µm; while the mitotic trough was at proestrus in all the follicles. Thecal mitosis was significantly lower than mitosis of the granulosa cells. In most of the follicles, mitotic activity in the thecal cells was highest at diestrus and lowest at metestrus. In both the granulosa and thecal cells, the timing of mitotic peaks and troughs varied according to the size of the follicles and the stages of the estrous cycle. In the granulosa cells mitotic peaks were maximal in the daytime (10.00 h, 16.00 h) and in some cases at night (04.00 h); and mitotic troughs were primarily during the night (22.00 h, 04.00 h) and in some cases in the day (10.00 h). In the thecal cells, however, mitotic activity in most of the follicles was distinctly higher in the daytime (16.00 h) than at night (22.00 h, i.e., evening). Thus, a prominent 24-hour mitotic rhythm was noticed in the ovarian follicles of the bandicoot rat.
Ultrastructural Aspects of the Primary in vitro Antibody Response of Mononuclear Cells in Human Blood
Authors: De Biasi Silvia , Villa Maria Luisa
Published: July 2008

Investigations on the morphology of cells that participate in immune responses in vitro have been limited because the recovery and identification of immunocompetent cells growing dispersely in conventional liquid cultures are technically difficult and allow only the observation of individual antibody-forming cells. Here we used a system in which focal proliferation of antisheep erythrocyte antibody-secreting cells has been induced in semisolid cultures of peripheral blood mononuclear cells. By this method, intact colonies can be observed by light microscopy at the center of each hemolytic area and then processed for electron microscopy without disrupting the connections existing among the cells. Two types of colonies develop: type I colonies which grow deeply into the agar and contain cells that undergo a complete process of differentiation from blast to mature plasma cell, and type II colonies which grow more superficially and do not seem to be directly involved in antibody production.
Incidence, Anatomy and Territories Supplied by the Posterior Gastric Artery
Authors: Trubel W. , Turkof E. , Rokitansky A. , Firbas W.
Published: July 2008

The posterior gastric artery, a branch of the splenic artery to the posterior gastric wall, was described for the first time by Walther in 1729. It was often” recognized by many authors since, but consequently ignored by anatomical and surgical textbooks until its rediscovery and description by Suzuki et al. [Ann. Surg. 187:134–136, 1978]. The incidence of the posterior gastric artery differs between 4 and nearly 100%. All authors describe posterior gastric regions being supplied by the posterior gastric artery, but sometimes also a branch running towards the superior pole of the spleen is cited. In our study of 104 corpses we found the posterior gastric artery with an incidence of 37.5%. In one third of these cases, a branch of the posterior gastric artery to the superior pole of the spleen was also detectable. Besides these results, the course of the posterior gastric artery to the corresponding organs and the importance of this vessel for the abdominal surgeon are discussed.
NADH-Dehydrogenase Reaction in Combination with Immunoperoxidase (PAP) Staining for Light Microscopic Observation on the Interneuronal Relations of the Enteric Nervous System of the Pig
Authors: Scheuermann Dietrich W. , Stach Werner
Published: July 2008

A novel procedure for a simultaneous demonstration of particular enteric nerve cell types and peptidergic nerve fibres has been developed by combining the histochemical reaction for NADH-dependent dehydrogenase and the unlabelled antibody peroxidase-antiperoxidase (PAP) method described by Sternberger. Whole-mount spreads were successively incubated in a NADH: nitroblue tetrazolium solution, fixed with a picric acid/ formaldehyde mixture, dehydrated, cleared and rehydrated before processing for immunocytochemical localization of the neuropeptide by the PAP method. The nerve cells appear heavily stained by deposits of dark blue formazan, whereas the peptide-containing nerves appear bright brown. In the myenteric and submucous plexuses of the porcine small intestine the devised method allows an appropriate identification of Dogiel’s type I, type II and type III neurons surrounded by varicose enkephalin-like immunoreactive fibre baskets with button-like twigs to the very surface of the ganglionic cells, suggestive of synaptic connections.
Multivacuolated Cells in Human Cartilage Canals
Authors: Rodriguez José I. , Delgado Emilio , Paniagua Ricardo
Published: July 2008

Light and electron microscopic examination of cartilage canals in 39 infants (from fetuses to 2 years of age) revealed the presence of multivacuolated cells in the connective tissue of the canals. These cells showed an irregular and electron-dense nucleus and cytoplasm; the latter.was almost filled by large, irregular, membrane-bound vacuoles without or with hardly apparent content. Histochemistry revealed a weakly positive stain with periodic-acid-Schiff, oil-red-o and muramidase techniques in these cells which seem to be degenerated macrophages.
Immunocytochemical Observations of Corticotropin-Releasing-Factor-Containing Neurons in the Rat Hypothalamus with Special Reference to Neuronal Communication
Authors: Shioda S. , Nakai Y. , Kitazawa S. , Sunayama H.
Published: July 2008

Synapses between neurons with corticotropin-releasing-factor-(CRF)-like immunoreactivities and other immunonegative neurons in the hypothalamus of colchicine-treated rats, especially in the paraventricular nucleus (PVN) and the supraoptic nucleus (SON) were observed by immunocytochemistry using CRF antiserum. The immunoreactive nerve cell bodies and fibers were numerous in both the PVN and the SON. The CRF-containing neurons had synaptic contacts with immunonegative axon terminals containing a large number of clear synaptic vesicles alone or combined with a few dense-cored vesicles. We also found CRF-like immunoreactive axon terminals making synaptic contacts with other immunonegative neuronal cell bodies and fibers. And since some postsynaptic immunonegative neurons contained many large neurosecretory granules, they are considered to be magnocellular neurosecretory cells. These findings suggest that CRF functions as a neurotransmitter and/or modulator in addition to its function as a hormone.
Morphological and Functional Changes in Several Endocrine Glands Induced by Hypothyroidism in the Rat
Authors: Gómez Dumm César L. A. , Cortizo Ana M. , Gagliardino Juan J.
Published: July 2008

The effect of hypothyroidism upon the morphology and the function of several endocrine glands was studied in radiothyroidectomized male rats. It was found that T3, T4, insulin, prolactin and corticosterone levels were significantly lower in hypothyroid rats. TSH levels were significantly higher in these animals while no changes were depicted in testosterone levels. The administration of T4 drew back to normal range the above-mentioned altered serum hormone levels. The studies performed with light microscopy revealed alterations only in the TSH secretory cells of the adenohypophysis. Conversely, when using the electron microscope to study the different endocrine glands, clear alterations were depicted in the TSH and prolactin secretory cells of the adenohypophysis, as well as in the pancreatic B cells and the cells of the zona fasciculata of the adrenal cortex. No abnormal changes were demonstrable at the level of the seminiferous tubules of the testis. All the above morphological changes were corrected by the administration of T4 to hypothyroid rats. These results suggest that the hypothyroid state is a complex hormonal dysfunction rather than a single hormonal defect. The secretory alterations are accompanied by fine cellular alterations in the corresponding glands.
The Effects of Dichloromethylene Biphosphonate on Osteoporotic Femora of Adult Castrate Male Rats
Authors: Wink C.S. , Onge M.St. , Parker B.
Published: July 2008

In a previous study we reported that castration of adult male rats resulted in femoral osteoporosis 4 months later. The present study tested the effects of dichloromethylene biphosphonate (Cl2MBP, formerly Cl2MDP), a bone resorption inhibitor, on the development of osteoporosis in femora of adult castrated male rats. One-year-old male Holtzman rats were assigned to three groups: sham-operated controls; castrated-no treatment; castrated+ Cl2MBP injections 3 times/week. The animals were sacrificed 4 months later. Femora from untreated castrated rats were osteoporotic, confirming our earlier study. Femora from Cl2MBP-treated castrates did not differ from those of controls and were significantly denser and more robust than those of untreated castrated rats. The results indicated that Cl2MBP treatment started immediately after castration prevented the development of femoral osteoporosis in adult castrated male rats.
Light Microscopic Observations of an Intraepithelial Granular Cell Type in the Bovine Parotid Gland
Authors: Gurusinghe Chandan J. , Birtles Mervyn J.
Published: July 2008

Bovine parotid gland intralobular ducts were frequently found to contain an intraepithelial granular cell type, adjacent to the basement membrane. Granular cells were non-migratory and polymorphic in appearance, with strong cytoplasmic basophilia and acidophil metachromatic granules. Such cells were not found in the bovine mandibular and sublingual glands. It is proposed that the granular cell may be similar or identical to the globule leucocyte cell type and functionally associated with the parotid gland. A possible role for parotid gland granular cells in ruminant mucosal immunity is also discussed.
Comparative Study of Histological and Kinetic Variations of the Digestive Mucosa and Pancreatic Parenchyma after Hypophysectomy in the Rat
Authors: Bastie M.J. , Balas D. , Laval J. , Bertrand J. , Ribet A.
Published: July 2008

Variations of the pancreatic parenchyma, the gastric mucosa and the intestinal mucosa were studied in adult male Wistar rats on day 8 and 15 after hypophysectomy. All results were compared with those obtained in pair-fed control rats. Hypophysectomy affected small intestine as well as gastric mucosa. Hypotrophy was observed on day 8 as most of the morphological parameters reached the maximal decrease. By contrast, hypoplasy occurred on day 15, when the labeling index (LI) decreased significantly. In the intestine, however, a decrease of the LI was observed only for the upper proliferative cells of the crypts. In the gastric mucosa, the LI was reduced only in the proliferative zone containing progenitor cells (isthmic region). Consequently, the cell differenciation is not similarly affected on all levels of the digestive tract.
Comparison of the Calcium Content of Different Tissues Present in the Human Mandible
Authors: Goret-Nicaise M. , Dhem A.
Published: July 2008

Qualitative and semi-quantitative comparisons of calcium content in the developing human mandible were performed by means of microradiographic and histophotometric analysis. Differences in calcium content between enamel, calcified cartilage, chondroid tissue and dentin are significant at the 1% level. Chondroid tissue and woven bone are almost similarly mineralized tissues
Some Characteristics of Intimal Folds in the Rabbit Aorta
Authors: Svendsen Einar
Published: July 2008

A stereomicroscopic study of fresh rabbit aorta has shown that the intimal folds form a special pattern which reappears when the aorta is relaxed after stretching. The pattern of intimal folds seems to be adapted to and may be the result of continuously repeated movements of the vessel wall. This supports the view hat intimal folds are present in vivo.
Perfusion-Induced Oedema Does Not Disrupt Perivascular Glial Sheaths in the Rat Area postrema: Evidence for an Inconspicuous Type of Cell Junction?
Authors: Sandoz Pierre A.
Published: July 2008

After perfusion fixation using phosphate-buffered glutaraldehyde, the rat area postrema always contained some portions with lacunar extracellular spaces in the neuropil. This was interpreted as a sign of local oedema due to perfusion-induced extravasation, made possible by the absence of an endothelial blood-brain barrier in the area postrema. All perivascular spaces were delimited from the nervous tissue by a continuous layer of astroglial processes. The cell appositions in these perivascular glial sheaths were not only seen in the regions of the area postrema displaying conventional morphology, but also persisted systematically in those regions containing lacunar extracellular space after fixation. At these sites, the glial sheaths had presumably endured a net outflow of extravasated oedema fluid in vivo. In the neighbouring neuropil at these locations, certain cell appositions with conventional intercellular clefts also persisted. These phenomena might both be interpreted as non-random, functionally important cell contacts with the inconspicuous ‘intercellular clefts’ containing unstained material. In the case of perivascular glia this might imply a partial restriction of diffusion between blood and brain tissue, allowing certain control or defence functions.
Location of the Angiogenic Activity in the Pregnant Human Uterus
Authors: Fuchs A. , Lindenbaum E. , Marcoudas N.G.
Published: July 2008

Angiogenic activity was known to be intensely dynamic during pregnancy with a geometric orientation towards the site of implantation. Therefore this study was designed to test whether the uterine lining of pregnancy, the decidua, induces angiogenic activity on the chorioallantoic membrane (CAM). Twenty-three decidual specimens obtained during legally induced abortions were implanted into the 9-day-old chick CAM. All decidual specimens showed strong angiogenic activity as measured by 9-fold increase in radial blood vessels, with a geometrical formation of ‘spokewheel’ pattern extending over a range of 1.2 cm within 48 h.
Erythrophagocytosis in Alveolar Capillaries of Goat Lung: Ultrastructural Properties of Blood Monocytes
Authors: Atwal Onkar S. , Saldanha Kevin A.
Published: July 2008

Glutaraldehyde-perfused lungs of 5 adult male and female goats were prepared for electron microscopy to study the properties of blood monocytes in the alveolar capillaries, with particular reference to intravascular erythrophagocytosis. Ultrastructural evidence is presented that the majority of intravascular monocytes were active in forming large uropods and filipods and were vigorously phagocytic for erythrocytes. Erythrocytes were engulfed intact and subsequently fragmented. The fragments were hemolysed and eventually converted into ghost erythrocytes and siderosomes. An electron-dense protein coat was consistently seen on the outer surface of the cell membrane of monocytes. Coated pits, endocytosis and some indication of internalization of the surface coat were evident. It is suggested that blood monocytes in the lung undergo a process of maturation to differentiate into active phagocytes as immediate precursors of alveolar macrophages.
Estradiol Modulation of Pineal Gland Activity in the Wild Bandicoot Rat, Bandicota bengalensis
Authors: Sahu Abhiram , Chakraborty Subrata
Published: July 2008

In the present study, the effect of estradiol dipropionate on the cytology and mitotic activity of the pineal gland was evaluated in adult ovariectomized and juvenile bandicoot rats, Bandicota bengalensis. Estradiol treatment for 5 days inhibited the ovariectomy-induced hypertrophy of the pineal gland, and increased the nuclear diameters of pinealocytes in juvenile males while having no effect on the pineal cytology of juvenile females. Estradiol injection induced mitosis in the pinealocytes of adult ovariectomized and juvenile bandicoot rats. Thus, estradiol exhibited a dual action (stimulatory and inhibitory) on the pineal gland of this wild rat.
Alizarin Red S-Stained Bone and Cartilage in Calcium Deficiency Provoked by Experimental Liver Injury in Rats
Authors: Virtanen Pauli , Lassila Veijo
Published: July 2008

Experimental liver injury with different stages was provoked in rats with daily injected doses of thioacetamide (ThAA). The dose recommended for both male and female rats was 50 mg/kg body weight. The liver damages caused were acute, subacute, cirrhotic and necrotic, with a traumatization period of 2, 7, 14 and 21 days. The loss of body weight under traumatization, indicating osteopenia, was in the case of female rats during the first experimental week markedly accelerated, and in the two subsequent weeks apparently inhibited when compared to male rats. The loss of body weight of male rats revealed a progressive fall. Vital staining was made giving intraperitoneally 200 mg/kg body weight of alizarin red S (ARS). The staining intensity was improved in the acute stage for both calvaria and tibia and in the necrotic stage for tibia only. It was impaired in the subacute stage for calvaria and tibia and in the necrotic stage for calvaria only. Prolonged traumatization with ThAA causes pathological defects in the liver and kidneys. Furthermore, the epiphyseal cartilage of necrotic-stage rats was bright red without any ARS staining.
Further Studies on the Effect of Low-Dose Laser Irradiation on Cultured Retinal Pigment Cells of the Chick
Authors: Tsang D. , Yew D.T. , Hui Betta S.W.
Published: July 2008

The effect of low-intensity laser irradiation on pigment cells cultured by chorioallantoic method was studied. Laser irradiation influenced the cell shapes and sizes of the pigment cells. Metabolically, this treatment increased thymidine uptake and incorporation but reduced those of leucine. The phagocytic activity as measured by latex particles uptake was not affected. It was concluded that the biological effect of laser irradiation on cell cultures depends on the dose applied, the individual tissue and other factors.