bluuebunny/crossref_metadata_2025 huggingface dataset:
Adrenergic Innervation of Fetal Pig Adipose Tissue
Authors: Hausman G.J. , Richardson R.L.
Published: July 2008

Histochemistry and electron microscopy were used to study the adrenergic innervation of subcutaneous adipose tissue in fetal pigs. Adrenergic innervation was present around arteries, arterioles, and adipocyte-associated capillaries. Nerve fibers were infrequently observed around veins, venules, and adipocytes. Ultrastructural features of nerves included mitochondria, clear synaptic vesicles, and a small number of vesicles with a core of electron-dense material. Innervation of adipose tissue was similar in 70-, 90-, and 110-day-old fetuses. Examination of fetuses decapitated at 45 days of gestation and removed at 110 days showed that adrenergic innervation was absent in adipose tissue of decapitated fetuses. Adrenergic innervation was also absent in adipose tissue from fetuses hypophysectomized at 72–73 days of gestation and examined at 110 days. These data indicate that fetal porcine adipose tissue may be under neural control by day 70 of gestation. Furthermore, an intact pituitary is necessary for the development of adrenergic innervation in fetal adipose tissue.
Über die Kanalsysteme im Os temporale und deren Rechts-links-Unterschiede
Authors: Lang Johannes , Hack Christian
Published: July 2008

The first part of the facial canal is the pars labyrinthica. Its mean lateral length is in our material 2.63 mm on the right and 3.03 mm on the left side. The mean width of the pore on the fundus area was 1.3 mm on the right side and 1.07 mm on the left. The geniculate fossa had a mean length of.2.54 mm on the right and of 3.14 mm on the left side. The widths of different areas of the pars labyrinthica and fossa geniculata were also measured. The angle between the first and second parts of the Fallopian canal was estimated with different methods. The mean width of the tympanic part of the facial canal was found to be 1.79 mm on the right side and 1.67 mm on the left, the mean width of the mastoideal part was 1.8 mm on the right side and 1.7 mm on the left. Distances of the mastoideal part of the Fallopian canal to mastoideal cells, ear drum, sigmoid sinus and external surface of the temporal bone were also measured. Measurements of the sigmoid sinus, the bulb of internal jugular vein and the cavum musculi stapedii are included, too. The ranges found in our material are also given.
Über den Nervus laryngeus superior und die Arteria laryngea superior
Authors: Lang Johannes , Nachbaur Stefan , Fischer Klaus , Vogel Elisabeth
Published: July 2008

Length, diameter and anastomoses of the nervus vagus and its ganglion inferius were measured in 44 halved heads. On the average, 8.65 fiber bundles of the vagus nerve leave the retro-olivary area. In the area of the jugular foramen is the near superior ganglion of the 10th cranial nerve. In this area were found 1.48 (mean value) anastomoses with the 9th cranial nerve. 11.34 mm below the margo terminalis sigmoidea branches off the ramus internus of the accessory nerve which has a length of 9.75 mm. Further anastomoses with the 10th cranial nerve were found. The inferior ganglion of the 10th nerve had a length of 25.47 mm and a diameter of 3.46 mm. Five mm below the ganglion the 10th nerve had a width of 2.9 and a thickness of 1.5 mm.The mean length of the superior sympathetic ganglion was 26.6 mm, its width 7.2 and its thickness 3.4 mm. In nearly all specimens anastomoses of the superior sympathetic ganglion with the ansa cervicalis profunda and the inferior ganglion of the 10th cranial nerve were found.The superior laryngeal nerve branches off about 36 mm below the margo terminalis sigmoidea. The width of this nerve was 1.9 mm, its thickness 0.8 mm on the right and 1.0 mm on the left side.The division in the internal and external rami was found about 21 mm below its origin. Between the n. vagus and thyreohyoid membrane the ramus internus had a length of 64 mm, the length of external ramus between the vagal nerve and the inferior pharyngeal constrictor’muscle was 89 mm. Its mean length below the thyreopharyngeal part was 10.7 mm, 8.6 branchlets to the cricothyroid muscle were counted. The superior laryngeal artery had its origin in 80% of cases in the superior thyroideal artery, in 6.8% this vessel was a branch of the external carotid artery. Its average outer diameter was 1.23 mm on the right side and 1.39 mm on the left. The length of this vessel between its origin and the thyreohyoid membrane was 34 mm. In 7% on the right side and in 13% on the left, the superior laryngeal artery reached the larynx through a foramen thyreoideum. Ranges of diameters and lengths of vessels and nerves in the larynx are given.
Changes in the Predentin Thickness and Mineralization Front Configuration in Developing Human Premolars
Authors: Couve Eduardo
Published: July 2008

The thickness of the predentin layer was studied at three different levels of developing human premolars. The results demonstrate that at the growing end next to the apex, where dentinogenesis is most active, predentin exhibits its greatest thickness (mean value 40.4 µm). However, at the coronal region, where primary dentin has been completely formed, predentin width is reduced to a mean value of 14.8 µm. Changes in the calcospheritic configuration of the mineralization front were established for each of the predentin levels studied. A comparative analysis of these calcospheritic changes and the morphology of fluorescent tetracycline lines detected in ground sections of premolars was established. Fluorescent lines observed at the coronal circumpulpal dentin showed large calcospheritic forms beneath the mantle dentin. However, lines found near the dentin-pulp border showed small calcospherites. It is concluded that the thickness of the predentin layer and the mineralization front configuration vary as a function of dentinogenic activity during development of human premolars.
Study of the Anatomic Metric Values of the Foramen Magnum and Its Relation to Sex
Authors: Catalina-Herrera C.J.
Published: July 2008

The sagittal and transverse diameters of the foramen magnum were examined in 100 human skulls (74 male, 26 female).The results were statistically analyzed and compared with those obtained by other authors. Our findings show that the sagittal and transverse diameters are clearly different, as well as the total area of the foramen magnum, these parameters being larger in male skulls than in female.
Surface Ultrastructure of Uterine Epithelial Cells in Women with Premature Ovarian Failure Following Steroid Hormone Replacement
Authors: Murphy C.R. , Rogers P.A , Leeton J. , Hosie M. , Beaton L. , Macpherson A.
Published: July 2008

Scanning electron microscopy has been used to study the apical surface of uterine epithelial cells in women with premature ovarian failure following steroid hormone replacement therapy. A variety of ultrastructural characteristics are identified which could indicate a uterus that is receptive for blastocyst implantation.
A Silver Impregnation Method for Embedded Central Nervous Tissue of the Rat
Authors: Ogawa Y. , Rama B. , Spoerri P.E.
Published: July 2008

A simple and yet reliable silver impregnation method, using potassium ferrocyanide, for demonstrating nervous tissue of the rat central nervous system embedded in paraffin or paraplast is described. The method reported here is compared and discussed with earlier techniques using potassium dicyanoargentate potassium ferrocyanide and potassium ferricyanide.
Duplication of Slit Diaphragms in the Cystic Glomeruli of Rabbits Treated with Methylprednisolone Acetate
Authors: Ros M.A. , Garcís-Porrero J.A. , Ojeda J.L.
Published: July 2008

Duplication of the slit diaphragms between the pedicels of the visceral and parietal podocytes of glomerular cysts induced by a single intramuscular injection of methylprednisolone acetate is reported here. These changes are not accompanied by modifications of the cell coat of the podocytes.
Annulate Lamellae as a Precursor or a Product of Paired Cisternae in Human Adenomatous Parathyroid Cells
Authors: de Menezes Yara , Sesso Antonio
Published: July 2008

Clusters of chief cells from a fragment of human parathyroid adenoma possess relatively few rough endoplasmic reticulum (RER) cisternae with scattered annulate lamella (AL) pores in cytoplasmic sectors close to the nucleus. Some of these cisternae exhibit winding profiles with smooth segments lying very close to the outer nuclear membrane. Other groups of cells exhibit well-developed stacks of RER either in continuity with or separated from AL. Two other tumor fragments show chief cells with few RER cisternae scattered in the cytoplasm and possess stacks with various amounts of AL and/or paired cisternae (PC), occasionally at perinuclear sites. Compartmental continuity between AL and PC is a frequent finding. Pore density in AL varies considerably between the stacks from different cells.
Effects of an Organosilicon Compound on the Tubular Apparatus of Rat Kidney
Authors: Haider Syed G. , Rolauffs Dorothea , Goslar Hans Günter , Stuhl Oskar , Birkofer Leonhard
Published: July 2008

Male adult Wistar rats were treated for 8 weeks with an organosilicone [2,2-dimethyl-4-(chloromethyl)-1,3-dioxa-2-silacyclopentane] employing two different dosages (25 and 50 mg/kg body weight i.p. daily) and the changes in the tubular apparatus of the kidney were investigated employing histological and enzyme-histochemical methods. The effects, more pronounced at the higher dosage, were the following: The brush borders of the proximal tubules were stuck together and disintegrated; only few epithelial cells remained intact showing a decreased activity of nonspecific esterases and the increase of β-hydroxybutyric acid dehydrogenase. The nuclei of most of the epithelial cells in the distal tubules were dislocated towards the enlarged lumen and the cytoplasma showed a decrease of nonspecific esterases and an increase of β-hydroxybutyric acid dehydrogenase. The collagen fibers in the walls of the collecting tubules were dislocated and disintegrated with a discontinuous border of Mg2+-ATPase; the nuclei of the epithelial cells were pyknotic, the cytoplasma showed an increase of β-hydroxybutyric acid dehydrogenase. The induced changes were partially reversible after a recovery period of 8 weeks.
Quantitative und morphologische Untersuchungen der Retinaentwicklung bei Trisomie-19-Mäusen
Authors: Lorke Dietrich E. , Engelmann Elisabeth
Published: July 2008

To investigate the development of the retinal layers, the eyes of mice with trisomy 19 have been examined by light microscopy between the 2nd and 15th postnatal day. The diameter of the eye, thickness of the entire retina and both relative thickness and nuclear density of each of the retinal layers have been measured and compared to those of chromosomally balanced control animals. Malformations of the eye, alterations of cell morphology or disturbed lamination can not be observed. Retinal differentiation of trisomy 19 mice is delayed by approximately two days. The development of all cellular constituents i. e. of both neuroectodermal and mesenchymal origin is retarded accordingly. The eyes of trisomy 19 mice are of reduced size. The relative thickness of each retinal layer follows a normal growth pattern; there is no indication for a selective impairment of the development of one particular layer. With the exception of the ganglion cell layer, nuclear densities of each retinal layer do not differ from those of control mice. The comparison of nuclear densities in the ganglion cell layer suggests that in trisomy 19 mice fewer postmitotic cells differentiate into mature retinal cells.
Ultrastructural and Immunocytochemical Changes of Prolactin Cells of Grafted Pituitary after the Injection of Dopamine in the Albino Rat
Authors: Ishibashi Toshiko , Shiino Masataka
Published: July 2008

Anterior pituitary glands were homografted into the anterior chamber of the eye in female rats. The pituitary grafts survived and were well vascularized three weeks after the transplantation.The prolactin cells were morphologically active as shown by their well-developed Golgi complexes and granular endoplasmic reticulum and the exocytosis of secretory granules. The injection of dopamine into the common carotid artery of the graft-bearing rat rapidly suppressed the granule extrusion and then gradually induced a remarkable morphological atrophy in the prolactin cells.
Femoral Expansion in the Adult Male Rat
Authors: Wink Carole S. , Armstrong Este
Published: July 2008

The length, total and cortical widths at midshaft, and robusticity of femora were measured in growing and mature male Holtzman rats. Analysis of covariance revealed significant differences in the regression coefficients (slopes) between young rats (1–4 months) and adult rats (5–16 months), indicating that, for a given increment in femoral length, young rats have a smaller increment in total femoral width than do adult rats. In addition, the results indicated that femoral expansion occurs in adult male Holtzman rats (5–16 months of age) without cortical thinning or loss of bone mass.
Immunocytochemical Studies on Thyroid Parafollicular Cells in Postnatal Development of the Rat
Authors: Zabel Maciej , Surdyk Joanna , Biela-Jacek Izabela
Published: July 2008

Studies were performed onWistar strain rats aged 1–720 days. Immunocytochemical reactions were used to detect calcitonin, somatostatin, calcitonin gene-related peptide (CGRP), cholecystokinin, serotonin, neuron-specific enolase (NSE), secretory protein-I, chromogranin and Ca-binding protein. In the parafollicular cells of the rat, the presence of calcitonin, somatostatin, CGRP, NSE and secretory protein-I could be demonstrated. The number of parafollicular cells increased with the age of animals, and the increase was particularly pronounced in the early postnatal period and after the first year of age. The number of somatostatin-immunoreactive cells decreased after birth and increased again after the first year of age. The number of calcitonin-immunoreactive cells increased in the early postnatal period independently of the increase in parafollicular cell number, forming frequently tumor-like outgrowths in 2-year-old animals. A small proportion of these outgrowths contained no calcitonin even if they did contain somatostatin, CGRP and NSE immunoreactivity. Evident changes in immunoreactivity in the first days after birth may reflect the sudden change in environment and may be associated with growth and differentiation. In any period of life, CGRP- and NSE-immunoreactive cells have constituted the most numerous groups and, therefore, the respective antigens seem to represent the most suitable markers of parafollicular cells in the rat.
The Blood Supply of the Stomach
Authors: Vandamme J.P.J. , Bonte J.
Published: July 2008

156 abdominal preparations were explored by arteriography, corrosion and dissection. The stomach is vascularized by four well-anastomosed main arteries: the arteria gastrica dextra and sinistra and the arteria gastroepiploica dextra and sinistra. Other important vessels include: the arteria gastroduodenalis, the arteriae gastricae breves for the upper half of the greater curvature, a posterior gastric artery (36%) an accessory left gastric artery (12%) and an arteria supraduodenahs.The main vessels give rise to some very specific collaterals, e.g. the omental arteries that may form an omental arcade (44%), supra- and infra-pyloric branches, retroduodenal branches, rami cardiaci, esophagei and tuberales and an accessory left hepatic artery.The gastroduodenal artery always arises at a fixed point.
Die Guyonsche Loge
Authors: Schmidt Hans-Martin
Published: July 2008

In 40 hands of adults the ‘loge de Guyon’ a narrow bounded area within the proximal hypothenar region, has been dissected to realize an exact determination of the important characteristics of size. Beside measurements of the wall structures in the region of the pisiform bone, the hook of hamate and the entrances of the loge, variations of muscles and the position of the ulnar artery and nerve with their terminal branches have also been examined.The deep palmar branch of the ulnar artery crosses the rami of the ulnar nerve on the palmar side in 65% of cases. The branch of the artery crosses on the dorsal side in 30% and in 5% the ramus profundus of the ulnar artery runs between both terminal branches of the ulnar nerve. The clinical significance of the loge is emphasized, whereas the irregular nomenclature in the national and international literature is discussed in detail.
Myofibroblasts in Human Palatal Mucosa
Authors: Boya J. , Carbonell A.L. , Martinez A.
Published: July 2008

Myofíbroblasts in human osseous palatal mucosa are described. They appear as fusiform or ramified cells, rich in homogeneous 60- to 70-Ångström-thick micro filaments, rough endoplasmic reticulum cisternae, and abundant pinocytotic vesicles in relation with the plasma membrane. On the surface of these cells there are small areas covered by basal lamina. Contacts between myofibroblast processes and other tissue elements are described. Small clusters of oxytalan fibers appear in the vicinity of these cells.
Adjustment of the Myelin Sheath to Axonal Atrophy in the Rat Spinal Root by the Formation of Infolded Myelin Loops
Authors: Krinke G. , Froehlich E. , Herrmann M. , Schnider K. , Da Suva F. , Suter J. , Traber K.
Published: July 2008

Atrophy of the L4 dorsal and ventral spinal roots was experimentally induced by unilateral sciatic neurectomy in groups of young (2 and 4 months) and older (12 months) albino rats. During the 4 months following neurectomy, the occurrence of infolded myelin loops (IMLs) was quantitatively examined in transverse sections prepared using perfusion fixation with glutaraldehyde and embedding in epoxy resin. The number of IMLs was higher on the operated side and increased with the time of survival and the age of the animals.The formation of IMLs is a characteristic early response of a large-caliber myelin sheath to axonal atrophy, probably reflecting the presence of redundant myelin.
Anatomical and Computed Tomographic Studies of the Pancreatic Tail
Authors: Rosen A. , Shikiar S. , Nathan H. , Oland J. , Sayfan J. , Orda R.
Published: July 2008

The location of the pancreatic tail in the lienorenal ligament and its relationship to the splenic hilus were studied in 32 computed tomography (CT) scannings and in 37 autopsy specimens. We found several anatomical variations in both study groups: the pancreatic tail did not penetrate the lienorenal ligament in 24% of the autopsy specimens and in 37.5% of the CT group. The tail was adjacent to the splenic hilus in 29.7% of the autopsies and in 25% of the CT group. We classified the anatomical variations into 4 categories, three of which could be well demonstrated on CTwith satisfactory correlation to the anatomical findings of the autopsy specimens.
Pericyte Response during Choriocapillaris Atrophy in the Rabbit
Authors: Korte Gary E. , Pua Florence
Published: July 2008

The rabbit and rat choriocapillaris atrophies in response to experimental destruction of the retinal pigment epithelium by intravenous injection of sodium iodate. This provides a convenient model of capillary atrophy. We have observed that pericytes are spared during this process; the atrophy is due to loss of endothelium only. Extensive examination of thin sections obtained 1 day to 11 weeks after administration of iodate showed that pericytes retained their normal relationship to the remnant capillary basement membrane left behind as the endothelial tube atrophied. This was most conspicuously manifested in their retention of processes longitudinally disposed along the sleeves of remnant basement membrane. The processes retained bundles of actin filaments that had dense regions along them and inserted into subplasmalemmal densities at basement membrane attachment sites, i.e. they had the characteristics of stress fibers.The pericytes did not phagocytose the debris of endothelial necrosis, in spite of their known phagocytic abilities. Necrotic endothelial cells were eliminated by sloughing into the capillary lumen. The observations support the idea that the function of pericytes in the choriocapillaris, the major source of nutrition for the retinal photoreceptors, resides in their contractility, and that pericytes do not remove necrotic endothelium during capillary atrophy.
Morphological Changes in Locus ceruleus of Albino Rats in Relation to Aging
Authors: Zhi-tan Cui , Tie-ming Zhang , Zhang-hai Su , Yen William W C.
Published: July 2008

Comparative studies were carried out under light, fluorescence- and electron-microscopic observations between young, adult and aged groups of albino rats with the following results: the neuronal packing density of locus ceruleus decreases with advanced age. In addition to the senescent loss of nerve cells, the surviving ones showed some shrinkage of perikarya and reduction or loss of Nissl substance. Some of them presented pyknosis, chromatolysis and loss of RNAin cytoplasm. Glial cells proliferated around the degenerating cells. Senescent cells showed an increase of heterochromatin and decrease of euchromatin. Changes in cytoplasmic organelles included the decrease of ribosomes, alterations in mitochondria and increase of lipofuscins. These senescent changes were thought to affect the absorption of nutrition, message exchange, protein synthesis, supply of energy and transport of materials by the nerve cells.
Peroxisomes in the Rat Brain and the Effects of Di-(2-Ethylhexyl) Phthalate during Postnatal Development
Authors: Dabholkar Arun S.
Published: July 2008

Peroxisomes were identified in the neurons of cerebral cortex of 12-day-old suckling rats from normal and plasticizer di-(2-ethylhexyl) phthalate (DEHP)-fed mothers. The study suggests that DEHP passed to the pups through the mother’s milk during nursing can induce peroxisomal proliferation in neurons during postnatal development.
Multilamellar Glial Envelopes of Synapses in the Pontine Nuclei of the Cat
Authors: Narlieva N.
Published: July 2008

Multilamellar glial envelopes of synapses were observed in an ultrastructural study of the pontine nuclei of cats. They consist of several concentric coils, representing lamellar expansions of the astrocytic processes. Glial envelopes completely wrap various synapses (axodendritic, axospinous, glomerulus-like complexes, and contacts between vesicle containing profiles). The possibility that multilamellar glial envelopes might play a role in isolating and protecting diverse neurotransmitters in the pontine nuclei from loss and mingling is discussed.
Immunohistochemical Study on the Endocrine Pancreas of Cattle with Special Reference to Coexistence of Serotonin and Glucagon or Bovine Pancreatic Polypeptide
Authors: Nakajima Seigo , Kitamura Nobuo , Yamada Junzo , Yamashita Tadayuki , Watanabe Tohru
Published: July 2008

Bovine pancreatic endocrine cells were investigated by light microscopic immunohistochemistry. Serotonin-immunoreactive cells as well as insulin-, glucagon-, somatostatin-, bovine pancreatic polypeptide (BPP)-immunoreactive cells were detected in the pancreatic islets. Generally, insulin-immunoreactive cells were distributed throughout the islet and the others took peripheral location. Since the distribution and shape of serotonin-immunoreactive cells were very similar to glucagon- and BPP-immunoreactive cells, serial sections were restained by using the elution method. All glucagon- and BPP-immunoreactive cells also showed serotonin immunore activity but glucagon and BPP immunoreactivities were never observed to be colocalized in the same cell. A small number of serotonin-immunoreactive cells were observed that showed serotonin immunoreactivity only.
Microvasculature of the Feline Stomach
Authors: Marais James
Published: July 2008

The feline gastric microvasculature was studied by corrosion of the injected vascular bed, which allowed evaluation of the vascular pattern of the different tunics. The serosal pattern consisted of numerous interconnected capillary vessels, forming a delicate network. Submucosal arteries supplied the muscular tunic through numerous anastomosing vessels that followed the direction of the smooth muscle fibers. The entire mucosal tunic was supplied by arterioles derived from the submucosal plexus; these gave rise to capillaries that surrounded the gastric glands and terminated in a diffuse, anastomosing subepithelial capillary network. Venules coursed through the mucosa in a perpendicular manner, forming submucosal veins.
The Two- and Three-Dimensional Structure of the Microcirculation of the Chick Chorioallantoic Membrane
Authors: Fuchs A. , Lindenbaum E.S.
Published: July 2008

The chick chorioallantoic membrane (CAM) is a common model for studying biological processes, but descriptions of the CAM circulatory system and especially experimental preparations of the CAM in shell-less eggs are both scant and controversial. We studied the CAM structure and the three-dimensional spatial configuration of the CAM vessels using five methods: in vivo stereoscopic observations, whole-mount preparations, histological sections, corrosion cast microinjection techniques and the reconstruction of a three-dimensional wax model. Our findings show that the CAM consists of a superficial two-dimensional layer composed of a network of a very dense capillary mesh, floating over and enclosing a deeper three-dimensional space in which medium and larger free-floating vessels are seen to supply and drain the superficial layer. It is interesting to note that no tips or sprouts of blood vessels were observed during the development of the CAM vessels. In a shell-less egg preparation, the capillaries were found in the mesoderm layer of the CAM and not in or superficial to the ectoderm as is the case in the CAM of the intact egg which adheres to the shell membrane.
Myocutaneous Vascular Territory of the Thoracoacromial Artery
Authors: Friedrict W. , Lierse W. , Herberhold C.
Published: July 2008

In order to clarify the vascularization of the pectoralis major muscle by the pectoral branch of the thoracoacromial artery, morphometric investigations and selective injection studies of the vessel were performed. A comparison with the anatomical orientation points clinically used for locating the vessel and its course confirms that the origin of the artery is at a constant spot at half the sternoacromial distance; the main vessel axis, however, deviates considerably from the clinically used acromioxiphoid axis in lateral direction.The lumen of the thoracoacromial artery has a range of more than 150% of the smallest vessel. Atherosclerotic alterations are not the reason for this variety but only an additional handicap for the vessel capacity. Two types of muscle-perforating arteries were found, and the cutaneous area of blood supply was defined.
Effects of Endocrine Glands and Hormone Replacement on the Mast Cell Count of the Harderian Gland of Mice
Authors: Shirama Kazuhiko , Kohda Masanori , Hokano Masami
Published: July 2008

There are marked sex differences in the Harderian gland of the C3H/He mouse strain, the females having a larger number of mast cells than the males as one of the major differences. Mast cell counts of the Harderian gland were made on male mice subjected to combinations of adrenalectomy, gonadectomy and administration of sex steroid hormones. Castration alone caused a significant increase in the count resulting in about three times the number found in intact males. Castration plus adrenalectomy increased the count over 6-fold, to levels close to those found in female mice. Administration of testosterone or estrone to the mice which had been castrated and adrenalectomized prevented the increase, while progesterone treatment had no effect on the count. Although the number of mast cells in the male Harderian gland was necessarily small compared to either the female gland or that of castrated and adrenalectomized males, no obvious dimorphism could be found microscopically.
Ultrastructure of the Secondary Tympanic Membrane in the Human Fetus
Authors: Shidu Yan , Zhimin Qiu , Ningshen Zhou
Published: July 2008

The normal secondary tympanic membrane in human fetuses was examined by transmission electron microscopy. The membranes in 5- to 9-month-old fetuses consist of the following three layers: (1) an outer squamous epithelial layer facing the middle ear, which is not formed until 4 months old; (2) a middle fibrous layer containing collagen, elastin, fibroblasts and fibrocytes, and (3) an inner layer of flat cells facing the scala tympani. Following the maturation of the fetus the epithelium is getting thinner and fibroblasts are reduced in number, but fibrocytes are increased and collagen and elastin grow gradually in density. The ultrastructure of the secondary tympanic membrane at 8 month is mature in type and shows the same characteristics as in the adult.This membrane has an important and complicated physiological function. The epithelium of the outer layer, with tight junctions and multiple desmosomes, provides a barrier to keep harmful substances out. The stability of the membrane provides protection against rupture, while the elasticity plays a role in the physiology of hearing as well.
La microvascularisation du sternum chez I’enfant
Authors: Simeoni U. , Sick H. , Koritké J.G.
Published: July 2008

46 sternums originating from 1-day- to 17-year-old children were injected with India ink and transparified.The intraosteal and medullary vasculature is described at different stages, as well as cartilage canals, vessels of the isolated ossification center, vessels of the ossification center connected with peripheral vascular structures or neighboring cartilage canals, and finally the transition to the adult pattern. With age, the centrifugal vascular distribution develops to a centripetal pattern.
Cytodifferentiation of Mouse Visceral Endoderm: Study with a Teratocarcinoma Antiserum
Authors: Monzo M. , Serra I. , Torres B. , Ruano-Gil D.
Published: July 2008

In this work we separated homogeneous embryoid bodies (EB); this population is composed of only endodermal vesicles of a visceral type. These EB were used to immunize rabbits. After absorption, the antisera were analyzed immunohistochemically in sections of 7.5- and 9-day-old mouse embryos, which showed a selective reaction to visceral endoderm. The cytodifferentiation of the visceral endoderm was studied.
Mechanism of Adaptation in the Mandibular Condyle of the Mouse
Authors: Kantomaa T. , Hall B.K.
Published: July 2008

The cranial base and whole mandible of 7-day-old mice were cultured for 1 or 2 weeks in a novel organ culture system that provided an articulating movement for the temporomandibular joints. The mandibles were articulating either in a closed or in an open position to simulate the in vivo mouth-breathing pattern. The reactions of the condylar processes were followed macroscopically and microscopically after osteoid or von Kossa staining. After 1 week of culture, small differences were found in the shape of the condylar processes between the two groups. After 2 weeks, significantly increased growth was observed superiorly in those condyles which had been working in a closed position and posteriorly in the condyles which had been working in an open position. Histologic analysis revealed that after 1 week calcification had proceeded faster in the posterior aspect of the condyles in the mandibles which had been working in a closed position as compared to the mandibles which had been working in an open position, and the difference was even more marked after 2 weeks. In the latter condyles calcification had proceeded markedly in the anterosuperior aspect. Osteoid staining showed that perichondrial mesenchymal cells had differentiated into osteoblasts in the posterior aspect of the condyles in those mandibles which had been working in a closed position. This led to a ceasing of expansive growth in the posterior aspect and thus to a more upwardly directed condylar growth. In mandibles which had been working in the open position to simulate the mouth-breathing pattern in vivo, chondrogenesis and thus expansive growth continued in the posterior aspect, leading to a more posteriorly directed condylar growth. We tried to simulate in a novel organ culture system the in vivo functional pattern where the mandible is lowered anteriorly as, for instance, in association with mouth-breathing.This led to a more posteriorly directed condylar growth as compared to control mandibles which had been functioning in a more closed position.The histologic findings after osteoid staining support the assumption that the differentiation of the mesenchymal cells in the anterior and posterior aspect of the condyle either into osteogenic or chondrogenic cells, depending on the position of the condyle in the fossa, has a role in the adaptive mechanism. The differentiation seems to be regulated by maturation of the cartilage which further is regulated by articulating function.
Occurrence of a Dense Plexus of Sensory Nerve Fibers Immunoreactive to Calcitonin-Gene-Related Peptide in the Cauda epididymidis of Rats
Authors: Yamamoto Miyuki , Kondo Hisatake
Published: July 2008

The occurrence, distribution and ontogeny of nerves displaying calcitonin-gene-related peptide (CGRP)-like immunoreactivity were studied in the male reproductive tract of rats. A marked regional difference in number of CGRP-immunoreactive nerve fibers was observed in the epididymis. The immunoreactive nerve fibers were particularly numerous in the cauda epididymidis, where the nerves were found in the capsular and interstitial connective tissue and further in the smooth muscle layer and the subepithelial connective tissue surrounding the duct. In the remaining portions of the reproductive tract proximal and distal to the epididymis, CGRP-immunoreactive nerve fibers were scarcely found in the connective tissues surrounding the duct, although a small number of the CGRP-immunoreactive nerve fibers was constantly found adjacent to small blood vessels throughout the male reproductive tract. CGRP-immunoreactive nerve fibers in the epididymis were first detected at embryonic day 18 when thin bundles or single fibers were evenly distributed in the interstitial connective tissue of the entire epididymal duct. A marked regional difference in number of CGRP-immunoreactive nerve fibers seen in the adult epididymis was established by postnatal day 14. In the epididymis of young rats treated neonatally with capsaicin, CGRP-immunoreactive nerve fibers were almost completely absent. This finding together with the distribution pattern of CGRP-immunoreactive nerve fibers different from that of the autonomic nerves so far reported strongly suggests that the immunoreactive nerves were sensory in nature.
Ethanol Alters Microvasculature Enzymes in the Rat Forebrain
Authors: Trulson Michael E. , Cannon Samuel , Ulissey Michael J.
Published: July 2008

Forebrain arterioles were analyzed histochemically to determine the effects of an acute administration of ethanol on key enzymes of aerobic and anaerobic metabolism as well as on the hexose monophosphate shunt in rats. The enzymes were glucose 6-phosphate dehydrogenase, cytochrome oxidase, lactate dehydrogenase, beta-hydroxy-butyrate dehydrogenase, and isocitrate dehydrogenase. All enzymes were quantified under two conditions: 1 h and 2 days after ethanol administration. Significant changes were noted in four of the five enzymes measured after 1 h and in all five enzymes when measured 2 days after ethanol administration. Our data suggest that ethanol may cause impaired metabolism in the forebrain microvasculature, which, in turn, may account for some of the characteristic behavioral effects of acute ethanol administration.
Effects of Immobilization of a Limb on the Maturation of a Peripheral Nerve in Kittens
Authors: Malathi Srivatsan , Batmanabane Mounissamy
Published: July 2008

Right or left hindlimbs of kittens were immobilized in a plaster cast, in the resting position. Three groups of animals belonged to the same age group, one to older, and another to younger. Kittens in the same age group were subjected to progressively increasing periods of immobilization, the older group to a shorter and the younger to the longest period. By virtue of this arrangement, it was found that the demonstrated changes in the peripheral nerve, which included a decrease in the myelinated nerve fibre population and a reduction in the mean nerve fibre diameter, have been proportionate among the animals in the same age group, more pronounced in younger, and less so in older ones, indicating that in younger animals longer periods of immobilization lead to a greater degree of harmful effects, although it was also evident that younger animals attempt to adapt to such adverse conditions.
Effects of Bacterial Colonization on Mucosal Structure of the Large Bowel of Neonatal Rats
Authors: Hill Robert R.H. , Cowley Heather M.
Published: July 2008

Micro-anatomical changes in colonic and caecal epithelia of infant rats between birth and weaning appear to be the outcome of the effects of bacterial colonization, superimposed on the natural postnatal ontogeny of the mucous membranes. Conventional rat pups between 15 and 22 days of age showed development of subepithelial spaces in both caecum and colon, rupture of the overlying epithelium and loss of whole enterocyte plaques. Antibiotic-treated animals retained the large-bowel mucosal morphology of the 10-day-old rat, without any of the lesions described in conventional infants. Mucosal lesions were typical of ischaemic damage, possibly triggered by lumen anoxia during colonization.
Qualitative Investigation of the Postnatal Development of Axon and Nerve Fiber Calibers in the Ventral Roots of Rats
Authors: Tonner P. , Lierse W.
Published: July 2008

The postnatal development of the ventral spinal roots of rats was studied with optical microscopic and morphometric methods. Adult rats show a craniocaudal decrease of axon and nerve fiber diameters which cannot be detected in younger animals. The bimodal differentiation of the nerve fiber populations occurs between the 15th and 20th day. Myelinated nerve fibers show a g ratio of 0.6 for all examined age groups.
Dichloromethylene Biphosphonate Retards Femoral Expansion in Normal and Castrated Adult Male Rats
Authors: Wink Carole S. , Hill Elizabeth M.
Published: July 2008

This study reports the effects of dichloromethylene biphosphonate (Cl2MBP), an inhibitor of bone remodeling, on femoral expansion in four groups of adult male rats; (1) sham-operated controls; (2) sham operated + injections of Cl2MBP; (3) castrated (osteoporotic), and (4) castrated + injections of Cl2MBP. After controlling for body weight, analyses of covariance revealed significant differences in total femoral width between animals that had received Cl2MBP and those that had not. The results indicated that Cl2MBP treatment retarded femoral expansion in both castrated and normal adult male rats.
Use of Dark-Field and Fluorescence Microscopy to Examine Extracellular Hyaline Accumulation in the Mouse
Authors: Wordinger Robert J.
Published: July 2008

Small foci of diethylstilbestrol-induced extracellular hyaline material were visualized within the mouse uterus utilizing dark-field and fluorescence microscopy following conventional hematoxylin and eosin staining. Hyaline was observed throughout the connective tissue stroma as well as between smooth muscle cells of the myometrium. The use of these techniques permits the rapid examination of small aggregates of hyaline material which are not visible with conventional hematoxylin and eosin staining and eliminates the need for time-consuming and complicated histochemical techniques. The procedures are simple and may also facilitate the quantitative (morphometric) analysis of this material.
Immunohistochemical Demonstration of Serotonin-Containing Nerve Fibers in the Mammalian Hippocampal Formation
Authors: Ihara Norihiko , Ueda Shuichi , Kawata Mitsuhiro , Sano Yutaka
Published: July 2008

The distributional pattern of serotonin-immunoreactive nerve fibers in the hippocampal formation of six different mammalian species (rat, chipmunk, hamster, cat, dog and monkey) was studied in detail by means of a modified peroxidase-antiperoxidase immunohistochemical method, using a specific serotonin antiserum. Furthermore, the density of varicosities distributed in each layer of the hippocampus was semiquantitatively analyzed. In all species investigated, the routes of serotonin fibers entering the hippocampal formation were found to be almost the same. These fibers were extensively distributed throughout the hippocampal formation, and had a characteristic arrangement corresponding to the laminar structure of this region. A dense innervation by varicose serotonin fibers was found in the stratum lacunosum-moleculare, but a few serotonin fibers were also distributed in the stratum lucidum of the CA2 and CA3 fields. The stratum pyramidale and the granule cell layer of the dentate gyrus contained a small number of serotonin fibers. The concentration and the direction of serotonin fibers were different in each area of each animal. Two peculiar observations should be stressed: (1) in the rat, the strata oriens and radiatum of CA2 and CA3 as well as the stratum lacunosum-moleculare displayed abundant serotonin fibers; (2) in the dog, abundant serotonin fibers were diffusely distributed in the CA1 field except for the stratum pyramidale and the most dense concentratioi > of serotonin fibers was seen in the stratum oriens of CA3.The present study provides a morphological basis for further study of the functional significance of serotonin in the limbic system.
Neural Differentiation of Melanocytes in Vitiliginous Skin
Authors: Bhanulyengar B. , Misra R.S.
Published: July 2008

Biopsies from 74 cases of vitiligo were examined to study the reactions of marginal melanocytes. In 35 cases, the melanocytes at the edge of the patch appeared highly dendritic and large with marked arborisation of the dendrites between the surrounding epidermal cells. These cells showed low pigmentation but a high enzyme activity which extended along the dendrites. The enzymes include tyrosinase/dopa oxidase, dopamine oxidase and noradrenaline activity, indicating that these cells have a biphasic melanogenic/adrenergic differentiation.This similarity between the dendritic melanocytes and the amelanotic melanoma cell line HT-18 is of interest.
Effects of Hypergravity Environment of the Ultrastructure of the Golden Hamster Parathyroid Gland
Authors: Shoumura Shizuko , Emura Shoichi , Ishizaki Noriko , Iwasaki Yuji , Yamahira Tomo , Ito Masaki , Isono Hideo
Published: July 2008

The fine structure of the parathyroid glands of golden hamsters exposed to 2, 5 or 10 g environment for 5 h was studied. In the centrifuged hamsters, many secretory granules are located in a peripheral position just beneath the plasma membrane of chief cells, and the Golgi complexes and cisternae of the granular endoplasmic reticulum are significantly increased compared with those of control animals. There are no significant differences between the control and centrifuged animals with regard to secretory granules, large secretory granules, lysosomes, vacuolar bodies and lipid droplets. These findings suggest that the secretory activity of the parathyroid gland may be stimulated in response to hypergravity environment.
Variability of Fiber Size, Capillary Density and Capillary Length Related to Horse Muscle Fixation Procedures
Authors: Mermod Laurence , Hoppeler Hans , Kayar Susan R. , Straub Reto , Weibel Ewald R.
Published: July 2008

Muscle samples were taken from the superficial part of the semitendinosus muscle of four standardbred horses to compare the effects of three different fixation procedures on fiber size and capillarity. Infiltration fixation in an extended position of the muscle was compared to immersion fixation and infiltration fixation in a flexed position of the limb. The capillary length density was used to estimate muscle capillarity. Infiltration fixation was found to be a viable alternative to perfusion fixation of muscles for morphometry of fiber size and capillary length density allowing muscle tissue fixation at a defined sarcomere length without fiber kinking.
New Synapses Associated with the Granule-Containing Cells of Rat Sympathetic Ganglia
Authors: Mekhail Nagy A. , Nawar Nabil N.Y. , Khairallah Philip A.
Published: July 2008

The synapses of the rat superior cervical sympathetic ganglion were studied with both conventional and ultrastructural histochemical methods. Besides the cholinergic synapses polarized from preganglionic fibers to sympathetic ganglion neurons, two morphologically and functionally different types of synapses were observed in relation to the small granule-containing (catecholamine-containing) cells of the rat superior cervical ganglion.The first type is an efferent adrenergic synapse polarized from granule-containing cells to the dendrites of the sympathetic ganglion neurons.This type of synapse might mediate the inhibitory effects (slow inhibitory postsynaptic potentials) induced by catecholamines on the sympathetic neurons. The second type is a reciprocal type of synapse between the granule-containing cells and the cholinergic preganglionic fibers. Through such synapses, these cells could exert a modulating effect on the excitatory preganglionic fibers. Therefore, we propose that these cells, through their multiple synaptic connections, exhibit a local modulatory feedback system in the rat sympathetic ganglia and may serve as interneurons between the preganglionic and postganglionic sympathetic neurons.
Occurrence of Methionine-Enkephalin-Like Immunoreactive Cells in the Feline Vagus Nerve
Authors: Maeda Sadaaki , Ichikawa Hiroyuki , Wakisaka Satoshi , Akai Michio , Inoki Reizo
Published: July 2008

The occurrence of peptidergic cellular elements in the feline vagus nerve was examined by an immunohistochemical method. Some methionine-enkephalin-like immunoreactive cells were present around a few capillaries within the vagus nerve, whereas substance-P- and vasoactive-intestinal-polypeptide-like immunoreactive cells were not observed. The methionine-enkephalin-like immunoreactive cells had an oval shape and their diameter was 7–10 µm. These cells appeared to be in contact with the pericyte of the capillaries. Though the physiological function of these enkephalin-positive cells is unclear, our findings suggest that they can act as endocrine cells and release methionine-enkephalin into the capillaries.
Topography and Identification of the Parathyroid Glands in the Calf
Authors: De Schaepdrijver L. , Simoens P. , Lauwers H. , De Geest J.P
Published: July 2008

There is considerable controversy in the literature concerning the topography of the parathyroid glands in the calf. In the present study, the position of the parathyroids III (external parathyroids) and of the parathyroids IV (internal parathyroids) was examined in 25 young calves, 10 veal calves and 5 adult oxen. Detailed data for the recognition and the collection of these glands are provided. The parathyroids III are well suited for removal in a fresh state, since they can readily be located. They are situated medial to the carotid bifurcation and ventrolateral to the vagus nerve where the latter gives off the cranial laryngeal nerve. In all young calves and in most veal calves they lie embedded in the subbasilar portion of the thymus, from which they can usually be differentiated easily by their color. However, they should not be confused with lymph nodes and hemal nodes, which are located in the neighborhood. Light-microscopical substantiation is therefore advisable. The parathyroids IV are not suited for collection since they cannot be distinguished macroscopically from the adjacent thyroid gland.