bluuebunny/crossref_metadata_2025 huggingface dataset:
Do C Cells of the Thyroid Gland of the Baboon Contain Estrogen Receptors?
Authors: Weaker Frank J. , Herbert Damon C. , Sheridan Peter J.
Published: July 2008

The uptake and retention of radiolabelled estradiol was studied in the thyroid gland of the female baboon. Four baboons were injected intravenously with 1 µm/kg body weight of 3H-estradiol. One animal, which served as a control, received an additional injection of 100 µg/kg body weight of unlabelled hormone. One hour after the injections, the animals were killed and the thyroid glands removed and processed for either autoradiography or autoradiography in combination with immunocytochemical staining for C cells. Localization of estradiol was observed in the nuclei of interstitial cells, but not in those of the follicular cells. Nuclei of immunostained calcitonin-containing cells in both the walls of the follicles and the interfollicular compartment were not radiolabelled. This study suggests that estrogen does not regulate calcitonin secretion by the C cells of the thyroid via a classical receptor system.
Immunohistochemical Study on the Presence of Immunoglobulins in Globule Leucocytes in the Tracheal Epithelium of Rats
Authors: Baert Johan , Frederix Maria
Published: July 2008

In the present study, the presence of immunoglobulins was immunohistochemically investigated in globule leucocytes in the tracheal respiratory epithelium of conventional rats, athymic nude rats and a germ-free rat. It was not possible to demonstrate any immunoglobulins in tracheal globule leucocytes. This and other dissimilarities with intestinal globule leucocytes are briefly discussed. On the other hand, peroxidase-antiperoxidase staining revealed the presence of surface immunoglobulins on the membrane of subepithelial mast cells. The previously postulated mast cell origin of the tracheal globule leucocytes is doubted, and the possibility that globule leucocytes should belong to the group of natural killer cells is discussed.
Growth of Calvarial Width
Authors: Alberius Per
Published: July 2008

This investigation was conducted to analyze growth in width of the rabbit calvarium. 15 male New Zealand white rabbits were subjected to regular stereometric examinations from 31 to 141 days of age after implantation of tantalum bone markers. The sagittal suture complex, i.e. the interfrontal and interparietal sutures, and the bilateral temporal sutures demonstrated similar growth rates in magnitude which moderately decelerated throughout the observation period. Transverse growth exhibited local growth fluctuations and short-term negative growth values in a well-balanced manner.
Mental Foramen and Mental Nerve: Changes with Age
Authors: Gershenson A. , Nathan H. , Luchansky E.
Published: July 2008

In a study of 525 dry mandibles and dissections in 50 cadavers, the mental foramen (MF) was found: single in 94.67% of the cases and multiple in 5.33%. Its shape was round in 34.48% with an average diameter of 1.68 mm and oval in 65.52% with an average long diameter of 2.37 mm. In 43.66% the MF was located in front of the apex of the root of the second premolar. In children before tooth eruption, the MF is somewhat closer to the alveolar margin; during the eruption period, the MF descends to half way between the margins, and in adults with the teeth preserved, the MF is somewhat closer to the inferior border. With loss of teeth and bone resorption the MF moves upwards closer to the alveolar border. In extreme cases of resorption the MF and the adjacent part of the mandibular canal are open at the alveolar margin. In the dissections the findings were similar. The mental nerve emerged from the MF closer to or at the alveolar border, according to the degree of resorption. In extreme degrees of resorption, the mental nerve and the final part of the inferior alveolar nerve were found directly under the gums. In these cases, the vestibular grooves became very shallow, and the mucosa passed directly from the cheeks over the alveolar ridge. Practical implications of the changes of the MF and mental nerve are discussed.
A Clinical and Anatomical Study of the Location of the Mental Foramen in Adult Chinese Mandibles
Authors: Wang Teen-Meei , Shif Chung , Liu Jiang-Chuan , Kuo Kuen-Jia
Published: July 2008

One hundred mandibles of adult Chinese cadavers of both sexes without missing teeth, alveolar bone resorption and malposition of teeth were studied. The anatomical location of each mandibular mental foramen was measured by using a combination of three previous methods. Our results showed that the location of the mental foramen below the apex of the lower second premolar (relation IV: 58.98%) was the most common. On average, the distance between the most anterior portion of the anterior border of the mental foramen and the mandibular symphysis was 28.06 mm, between the most anterior portion of the anterior border of the mental foramen and the posterior border of the ramus 74.14 mm, between the inferior border of the mental foramen and the lower border of the mandibular body 14.70 mm, between the superior border of the mental foramen and the bottom of the lower second premolar socket 2.50 mm. The distance across the mental foramen between the alveolar crest and the lower border of the mandibular body was 30.29 mm. Our results were compared with those of other investigators. The significance of identifying the anatomical location of the mental foramen in dental practice is discussed.
Evidence for a New Type of Juxtamedullary Nephron in the Rabbit Kidney
Authors: Ojeda J.L. , Ros M.A. , Garcia-Porrero J.A.
Published: July 2008

The microanatomy of a unique type of juxtamedullary nephrons has been studied in the rabbit kidney by means of corrosion casts, scanning electron microscopy and the air cast method. The nephrons described in this paper are located in the outer stripe of the outer medulla and are the only nephrons that are not arranged radially within the kidney. They differ from other juxtamedullary nephrons in the morphology and course followed by the proximal tubule and by the close relationship that they establish with the arcuate vessels. The glomerulus of these nephrons is supplied by a short afferent arteriola that arises directly from the arcuate artery. Because of the special characteristics of these nephrons we have named them ‘arcuate nephrons’. The morphology, spatial relationships and vascularization of the arcuate nephrons suggest that these nephrons differ functionally from the other juxtamedullary nephrons. Possible developmental factors responsible for the special microanatomy of the arcuate nephrons are analyzed.
Anatomy – Analysis and Synthesis
Authors: Warwick Roger
Published: July 2008

Scientific knowledge is a continuum, and anatomy is a part of this subject to the same methods, principles, and the need of synthesis, both within anatomy and with other syntheses. Western science is the spearhead of human progress in understanding the universe around us and the world of Earth, from which we cannot escape. Science may also, in its power of synthesis, bringing together not only those who practise it but also uniting the nations. Excellent as are the applications of science in technology, knowledge has its own value in producing a synthesis of human awareness, – and also it may prevent us from ruining the Earth, which is our only possible home.
Relations between Nucleolar Morphometric Parameters and Pre-rRNA Synthesis in Animal and Plant Cells
Authors: Nin Gerardo H. Vá;zquez , Echeverría Olga M. , Zavala Guadalupe , Jiménez-García Luis F.J. , Gonzalez Marco A. , Parra Rosario
Published: July 2008

In order to study if there are differences between cells of the same tissue with one and two nucleoli, nuclear and nucleolar volume, density of tritiated uridine incorporation, amount of DNA per nucleus and intensity of cytoplasmic basophilia were measured in mononucleolated and binucleolated rat epithelial endometrial cells, in onion root meristematic cells and in chick embryo matrix cells of the central nervous system, neuroblasts and neurons. No significant differences in nuclear volume, density of tritiated uridine incorporation and amount of DNA per nucleus were found between cells of the same type with diverse numbers of nucleoli. Binucleolated endometrial cells, matrix cells, and root meristematic cells have biphasic distributions of nucleolar volumes. One peak of this distribution roughly coincides with the nucleolar volume of mononucleolated cells, the other peak corresponds almost to double the volume. As the density of uridine incorporation is the same irrespective of the nucleolar number and volume, the cells with larger nucleolar volumes have higher pre-rRNA synthesis. These cells also have higher amounts of ribosomes in the cytoplasm, as revealed by the photometric study of basophilia. It is concluded that in this population of cells the ribosomal production is regulated to a higher steady equilibrium than in the general population. This difference is not due to polyploidism or to the increased DNA content of G2 phase cells. Binucleolated neuroblasts and neurons have nucleolar volumes similar to those of mononucleolated ones.
Quantitative Studies of Rat Carotid Body Type I Cell Nerve Endings
Authors: Pallot D.J. , Blakeman N.
Published: July 2008

The results of a stereological and morphometric analysis of rat carotid body type I cell nerve endings are described. 66.9% of endings possessed symmetrical junctions. Of the remaining endings, 3.6% were presynaptic and 26% were postsynaptic to type I cells; 3.6% of endings had a reciprocal configuration. Apart from membrane specialisations, no other ultrastructural criteria were found to distinguish the different types of endings. Ventilation with 100% and 10% oxygen showed that the hypoxic mixture reduced synaptic vesicle concentration in the nerve endings; this effect was independent of the innervation to the carotid body.
Surface Area of the Atlanto-Occipital Articulations
Authors: Mysorekar V.R. , Nandedkar A.N.
Published: July 2008

The surface areas of the occipital condyles of 101 skulls and of the superior articular facets of 103 atlases have been measured to ascertain bilateral asymmetry and dominance. The atlases show a tendency to have larger facets and the occipital bones tend to have larger condyles on the right side.
Development of Semitendinosus Muscle in Pig Fetuses with Spinal Cord Lesions
Authors: Hausman G.J. , Campion D.R. , Thomas G.B.
Published: July 2008

The effect of upper motor neuron regulation on the development of the semitendinosus muscle was studied in the fetus. A region of the fetal spinal cord at the level of the upper cervical vertebrae was destroyed by cauterization at 45 days of gestation. Fetuses with intact spinal cords served as controls. One cauterized fetus and one control fetus were obtained from each of six crossbred sows at 110 days of gestation. From each fetus one semitendinosus muscle was removed for histochemistry and the contralateral muscle was removed, weighed and utilized for biochemical analyses. Body weights and muscle weights were not significantly different (p > 0.05) between the two groups. Transverse sections (cryostat) of muscle were stained for lipid and the following enzymes: acid ATPase, NADH-TR, and esterase. Lipid and enzyme cytochemistry showed that sections from cauterized and control fetuses had identical fiber type patterns. Motor endplates, as studied with esterase reactions, were not affected by spinal cord cauterization. Mean values for percentage of muscle dry weight, DNA, RNA, protein, glycogen content and minimum fiber diameters were similar for cauterized and control fetuses (p > 0.05). These data illustrate that in the porcine fetus the central nervous system proximal to the α-motoneuron exerts little control over muscle cell development.
Immunoreactive Prolactin in Mouse Urethral Glands
Authors: Tsubura Airo , Morii Sotokichi , Mori Takao , Nagasawa Hiroshi
Published: July 2008

Immunoreactive prolactin was demonstrated in the acinar cells of urethral glands in some inbred strains of mice by immunoperoxidase technique. The significance of the presence of prolactin or its related substances in the urethral glands in relation to their role in the urinary tract is discussed.
Variations of Supraorbital Bony Structures in Sienese Skulls
Authors: Guidotti A. , Bastianini A. , De Stefano G.F. , Hauser G.
Published: July 2008

Various non-metrical traits were examined in the supraorbital region in a series of skulls of recorded sex (147 males, 130 females), age (18–80 years) and provenance (Siena and surroundings), using a standard method of categorization and notation introduced by two of the authors in 1983. The results are discussed from a topographic-anatomical point of view in relation to trait variation and with respect to the usefulness of the method applied for population studies.
Ultrastructural Studies of the Transitional Zone in the Nasopharyngeal Epithelium, with Special Reference to the Keratinizing Process in the Mouse
Authors: Nakano T.
Published: July 2008

In the nasopharynx of the SMA mouse, the ‘intermediate epithelium’ occupies the transitional zone between the ciliated columnar and the stratified squamous epithelia. The intermediate epithelium showed gradations ranging from ciliated stratified low-columnar through stratified cuboidal to stratified squamous type. It is suggested that the intermediate epithelium shows the various stages of the epithelium transforming from the ciliated columnar to the stratified squamous epithelium, and that the basal cells ofthe ciliated columnar epithelium serve as the germinal layer for the transformation. The intermediate epithelium containing a few keratohyalin granules and many membrane-coating granules represented earlier stages of keratinization. The width of the microprojections in the stratified squamous epithelium was about doubled compared to that in the intermediate epithelium. It is suggested that the difference in width is caused by cell membrane distortion associated with keratinization and is regarded as an important marker of the start of keratinization.
Muscle Fibre Typing in the Human Pharyngeal Constrictors and Oesophagus: The Effect of Ageing
Authors: Leese G. , Hopwood D.
Published: July 2008

Myosin-ATPase fibre typing revealed type 1 predominance (81%) in the human oesophagus and type 2 predominance in the pharyngeal constrictor (33% type 1) indicative of widely different functions. Fibre diameters were around 30 µm, significantly smaller than skeletal muscle. No significant change in mean fibre diameter or percentage of fibre type was seen with ageing, but atrophy and compensatory hypertrophy led to an increased variability in fibre diameters with age. No sex differences were observed, probably reflecting a similar usage of these muscles and contrasting with skeletal muscle.
Fine Structure of the Tapetum cellulosum of the Grey Seal (Halichoerus grypus)
Authors: Braekevelt C.R.
Published: July 2008

The morphology of the tapetum lucidum of the grey seal (Halichoerus grypus) has been studied by light and electron microscopy. The reflective layer in this species is a tapetum cellulosum situated in the choroid and covering the entire effective fundus. Posteriorly the tapetum is composed of 30–35 layers of flattened polygonal cells. This number gradually declines to 15–20 layers in the extreme periphery. Near the retinal epithelial layer the tapetal cells are larger and more regular (brick-like) in arrangement whereas further from the retina the tapetal cells become more irregular in outline and more widely separated by collagen fibrils and connective tissue cells. In this outer region the tapetal cells are gradually replaced by melanocytes of the choroid. Within the tapetal cells a few mitochondria and profiles of smooth endoplasmic reticulum are scattered peripherally while the majority of the cell organelles are clustered near the centrally located vesicular nucleus. The dominant feature of the tapetal cells is, however, an accumulation of numerous electron-dense rodlets of presumed zinc cysteine. These rodlets are the reflective material of the tapetum and are arranged with their long axes perpendicular to the incoming light. The orientation of these rodlets is usually uniform within each tapetal cell but varies between adjacent cells. The diameter (0.10 µm) and spacing (0.15 µm) of these rodlets is consistent with the principles of constructive interference. Blood vessels penetrate the tapetum at right angles to supply the choriocapillaris which is indented into the amelanotic retinal epithelium to give a flat reflective surface to the tapetum.
Innervation of the Canine Pancreas after Vagotomy
Authors: Radke R. , Stack W.
Published: July 2008

This contribution deals with the ultrastructure of the pancreatic nervous system of the dog 14 days and 5 months after bilateral truncal vagotomy. No major ultramorphological changes in the axons or their organelles (vesicles, mitochondria, microtubuli) were observed, and there appeared to be no reduction in the numbers of sympathic and cholinergic axis cylinders (material fixed in glutaraldehyde and potassium permanganate) or neurocellular contacts.
Study of Histomorphometric Changes of the Mandibular Condyles in Neonatal and Juvenile Rats after Administration of Cyclophosphamide
Authors: Wang Teen-Meei , Shih Chung
Published: July 2008

Forty 1-week-old Sprague-Dawley rats were divided into 4 groups of 10 animals each. Five rats of each group served as the controls, and another 5 were given weekly intraperitoneal injections of 20 mg cyclophosphamide (CTX, Endoxan, Cytoxan) per kg of body weight. The animals of each group were sacrificed either at 1 3, 5, or 7 weeks after initial intraperitoneal injection of CTX or water. The mandibular condyles of all rats were assayed histomorphometrically for changes on cartilage and bone cells, and other elements. The results showed a decreasing tendency in the thickness of the cartilage layer, the number of prechondroblasts, the number of chondrocytes, the percentage of cartilage matrix, the percentage of hard tissue, the bone surface perimeter, the number of osteoblasts, the number of osteoclasts, and the average number of nuclei per osteoclast in the condyles at 1 or 3 weeks after initial CTX treatment. After 7 weeks of treatment with CTX there was a significant decrease in the thickness of the cartilage layer, the number of prechondroblasts, and the numbers of both osteoblasts and osteoclasts per square millimeter of bone surface in the condyles, when compared with those of the control groups. In addition, after 5 or 7 weeks of CTX treatment there was a significant decrease in the percentage of hard tissue, the number of osteoblasts and the number of osteoclasts. Furthermore, changes in the morphology and size of the bone cells were also observed in all the rats. The reduction of the thickness of the cartilage layer was due mainly to a marked decrease in the* number of proliferative chondrocytes and the percentage of the cartilage matrix. All these findings demonstrated that a treatment of 20 mg CTX per week for 5 or 7 weeks had a cumulative effect which inhibited bone formation and affected both normal mandibular growth and facial profile in the juvenile rats. The cytotoxic effect of CTX also exerted an influence on the mitotic division of bone cells and the trabecular volumetric density of the madibular condyle.
Isoproterenol-Induced Myocardial Ischemic Injury in the Rabbit: Functional and Ultrastructural Alterations
Authors: Bhimji S. , Godin D.V. , McNeill J.H.
Published: July 2008

The functional and ultrastructural changes observed during myocardial ischemic injury (Mil) in the rabbit are described. Mil was induced by repeated subcutaneous injections of increasing doses of isoproterenol (ISO; 0.5 mg/kg on day 1, to 15.5 mg/kg on day 15). Measurement of cardiovascular changes revealed a significant decrease in the mean arterial pressure and an increase in heart rate of the ISO-treated animals. ISO treatment also initiated a variety of atrial and ventricular arrhythmias, including ventricular fibrillation, as well as significant ST segment elevations and the appearance of Q waves. Electron-microscopic analysis of hearts from ISO-treated animals showed accumulation of lipid and depletion of glycogen. The myofibrils had poorly defined Z bands and appeared as a homogenous mass. The most marked effects of ISO treatment were on the mitochondria, which appeared swollen and fragmented. The mitochondrial cristae were also disrupted and fragmented. A few amorphous electron-dense bodies were observed in and around the mitochondria. The changes observed in this study are qualitatively similar to those observed in the rabbit following coronary artery ligation.
Effects of Methamphetamine on Arterioles of Rat Caudate Nucleus and Midbrain
Authors: Cannon Samuel , Kapes Evelyn D. , Trulson Michael E.
Published: July 2008

No differences in arteriolar metabolic profiles from rat caudate nucleus, ventral tegmental area or substantia nigra were observed between saline-control and methamphetamine HCl-treated (20 mg/kg, i.p. twice daily for 10 consecutive days) animals. Arterioles from the above regions of forebrain and midbrain are metabolically active vessels with a capacity for aerobic and anaerobic metabolism. These results suggest that a high dose of methamphetamine does not alter cerebral arteriolar metabolism in the areas examined.
Influence of Conventionalization on Small-Intestinal Mucosa of Germ-Free Wistar Rats: Quantitative Light Microscopic Observations
Authors: Ishikawa K. , Satoh Y. , Tanaka H. , Ono K.
Published: July 2008

Germ-free rats were inoculated with microbial flora from feces of conventionally reared rats and the mucosal structure was quantitatively observed at different time intervals after the inoculation and at different regions of the small intestine. In the ileum, desquamation figures were frequently seen on the villus tip, and several parameters of the mucosal elements, i.e., villus and crypt lengths, mitotic figures, goblet cells and thickness of lamina propria were significantly increased after the inoculation. On the other hand, in the duodenum and jejunum, such parameters except for the lamina propria showed no remarkable change during the course of the experiment, though the villus/crypt ratio increased temporarily at half a day after the inoculation. These regional differences of the mucosal response to the inoculation may be due to the different populations of microbial flora which settled in each region of the small intestine.
Developmental Stages in Permanent Porcine Enamel
Authors: Robinson C. , Kirkham J. , Weatherell J.A. , Richards A. , Josephsen K. , Fejerskov O.
Published: July 2008

Developing permanent teeth of different ages were obtained from Danish Landrace pigs. Visibly distinct zones on their enamel surfaces were shown to correspond to changes in chemical composition previously reported for other species. The time of appearance, rate of progress and duration of each stage was determined for each tooth type.
Données histochimiques et ultrastructurales sur l'innervation adrénergique et cholinergique de l'épididyme chez la souris
Authors: Nouhouayi Yolande , Négulesco Irina
Published: July 2008

The adrenergic and cholinergic innervation of the epididymal duct in the mouse has been investigated using histochemical methods and electron microscopy. This study demonstrates that the epididymal innervation of the mouse does not really differ from that of other mammals. Cholinergic nerves are mainly vascular, even in the cauda where cholinesterase activity is increased within the tubular musculature. Catecholamine fibres ensure the motricity of the wall of the canalicular system, particulary the terminal segment where the smooth muscle fibres are specifically differentiated.
The Lamina cribrosa in the Eyes of Rats, Hamsters, Gerbils and Guinea Pigs
Authors: Johansson Jan-Olof
Published: July 2008

The scleral lamina cribrosa in the eyes of adult rats, hamsters, gerbils and guinea pigs was examined by ordinary histology and by scanning electron microscopy after soft tissue digestion. The complexity of the lamina, when mounted for scanning electron microscopy, was graded on a scale of 0 to 4.5 by three independent observers under × 60 magnification in a stereo microscope. The observers were unaware of the species and were offered the 44 specimens twice in random order. The average variance attributable to an observer was 22 ± 3% (SE) of the total variance of the gradings. The rat eyes had the least developed lamina cribrosa, with only 1–2 layers of sparse connective tissue. The mean complexity grading of 12 rat eyes was 1.6 ± 0.15. The lamina cribrosa of the eyes of gerbils and guinea pigs was much more developed with at least 3 layers of abundant connective tissue, the mean grades of complexity being 3.4 ± 0.09 and 3.5 ± 0.15, respectively, in 12 eyes of each species. The lamina cribrosa in the hamster eyes was somewhat more developed than that of the rat, but much less than that of the gerbil and guinea pig. The mean grade of complexity was 2.4 ± 0.14 in 8 eyes. In 6 pairs of rat eyes there was no correlation in grade of laminar complexity between the two eyes of the same animal. The present study makes the rat eye a candidate for experiments where a possible influence of the lamina cribrosa as such is undesired.
Freeze-Fracture Replica Studies of Effects of ACTH Treatment and Hypophysectomy on the Cell Surface of the Rat Adrenal Inner Cortex
Authors: Setoguti Takao , Inoue Yasuhisa , Shin Masashi
Published: July 2008

The morphological change of the cell surface in the inner zone of the adrenal cortex was studied in intact, hypophysectomized, and ACTH-treated hypophysectomized rats, using freeze-fracture replicas. In both intact and hypophysectomized ACTH-treated animals, the P fracture face of the plasma membranes of the cortical cells facing capillaries shows groups of characteristic finger-shaped microvilli, which arise horizontally from the edges of a small cavity on the cell surface to form various configurations ranging from incompletely organized, flower budlike to complicated, arboraceous ones. In the non-treated hypophysectomized animals, however, the microvilli in such groups decrease in number and shorten in length but increase in width, looking like a blade of a prickly-pear cactus or an irregular-shaped plate. On the other hand, presumptive exocytotic and endocytotic specializations of intra-membranous particles were observed on the lateral plasma membrane, but they appeared only rarely and in both normal and experimental animals.
Morphology of the Neural Lobe of the Hypophysis in Rats Treated with Furosemide
Authors: Vazquez R. , Carretero J. , Dominguez F. , Riesco J.M.
Published: July 2008

The changes found in the neurosecretory axons of the neural lobe of the hypophysis were studied in rats treated with furosemide for three days: over the whole period of treatment, the animals, according to each group, were deprived or not of water. In the animals with free access to water the axons contained neurosecretory granules with scarce content and low electron density; only some of them had vacuoles and autophagic bodies. In the animals deprived of water axon morphology was variable and axons showing vacuoles and autophagic bodies were abundant, as well as those presenting lamellar and dense bodies and also those in which filaments prevailed. The most outstanding modifications in this last group of animals were related to the dehydration and were not found in those animals which were given access to water again and which were in consequence rehydrated.
Ultrastructural Observations on the Intraodontoblastic Collagen Fibrils of the Mouse Tooth Germs
Authors: Ishizeki Kiyoto , Sakakura Yasunori , Nawa Tokio
Published: July 2008

We examined electron-microscopically and histochemically the ultrastructural features of the intraodontoblastic collagen fibrils of the mouse. These collagen fibrils were most common in secreting odontoblasts (pre-odontoblasts) of the maturating stages. In such cells they were most numerous at the peripheral zone of the Golgi apparatus, and were sometimes seen in odontoblastic processes. Intraodontoblastic collagen fibrils also had morphological variations including a banded structure enclosed by limiting membranes of vacuoles, fusion with primary lysosomes, and an electron-dense material covering with a structure that was not banded. Study of acid phosphatase activity showed that these structural changes were caused by the degradation of intraodontoblastic collagen fibrils by lysosomes. The results of studies of the permeation of lanthanum nitrate and the alkaline phosphatase reaction showed that these collagen fibrils were separate from the extracellular matrix and that there was no phagocytosis of the odontoblasts.
Morphology of the Neural Lobe of the Hypophysis in Rats Treated with Furosemide
Authors: Vazquez R. , Carretero J. , Blanco E. , Carvajal J.C.
Published: July 2008

Following three days of furosemide administration, the characteristics of the pituicytes in the neural lobe of the rat hypophysis were studied. The pituicytes of the animals which were treated with furosemide and had access to water during the treatment showed scarce cytoplasm organelles, conferring them with a clear appearance (light pituicytes), and a frequent finding was neurosecretory axons enclosed in their own cytoplasm. In the animals deprived of water during treatment, the pituicytes were dense (dark pituicytes) elongated, with a well-developed Golgi apparatus, numerous profiles of smooth endoplasmic reticulum and frequent annular gap junctions. It is concluded that the dehydration induced by the diuretic agent is the cause of the prevalence of the dark pituicytes.
Biochemical Anatomy of Human Bone: Comparative Study of Compact and Spongy Bone in Femur, Rib and Iliac Crest
Authors: Mbuyi-Muamba Jean-Marie , Dequeker Jan
Published: July 2008

Using EDTA extraction procedure, compact and spongy bone from human femur, rib and iliac crest were compared in terms of their content in collagen, sialoprotein, proteoglycan and carbohydrate. The bone matrix sizes displayed significant variations, the femur having the smallest size and iliac crest the largest one. No significant difference in the matrix size has been found between the spongy and compact bone. The EDTA extractability of the spongy bone was higher than that of the compact bone, with femur showing the lowest extractability. The collagen content of the 3 bones studied was similar although the femur had slightly lower values. The sialic and uronic acids and hexose contents were higher in the femur than in the rib and iliac crest. The collagen/hexose, collagen/sialic acid and collagen/uronic acid ratios in the bone matrix were highest in the iliac crest and lowest in the femur, suggesting that alterations in the amounts of bone matrix can affect the mechanical properties of different parts of the bony skeleton and vice versa.
Freeze-Etching Study of Synaptosomes from Rat Cerebral Cortex
Authors: Surchev L.
Published: July 2008

Synaptosomes from rat cerebral cortex were studied using the freeze-etching technique. The intramembranous structure of the pre- and postsynaptic membranes was examined. Particles with an electron-dense spot on their apex are reported from all fracture faces. Most probably these are related to transmembrane channels whose significance in the synaptic transmission is discussed.
Ultrastructural Studies on White Adipocyte Differentiation in the Mouse Mammary Gland following Estrogen and Relaxin
Authors: Bani-Sacchi Tatiana , Bianchi Stefano , Bani Gastone , Bigazzi Mario
Published: July 2008

White adipocyte differentiation was studied ultrastructurally in the mouse mammary gland following stimulation with 17β-estradiol and relaxin. These hormones have been previously demonstrated by us to induce hyperplasia and hypertrophy in the adipose cells of the mouse mammary gland. Following hormone treatment new fat cells are formed around the growing ducts. In these sites there is a close relationship between blood vessel growth and adipocyte development, and stromal areas featuring embryonic fat organs can frequently be found. In the sites of adipocyte differentiation the most numerous cell types are undifferentiated mesenchymal cells and preadipocytes, while fibroblasts and macrophages are much less common. No endothelial cells or pericytes were found detaching from the blood capillary walls. There were no fibroblasts or macrophages containing intracellular lipid deposits. Actively degranulating mast cells were frequent. The above findings strongly suggest the direct origin of adipocytes from perivascular mesenchymal cells, without the intermediate stages of well-differentiated fibroblasts, macrophages, endothelial cells or pericytes. The earliest morphologically recognizable stage in adipocyte differentiation is a ‘pale preadipocyte’, characterized by its irregular shape due to cytoplasmic processes, clear cytoplasmic matrix, well-developed organelles (especially ribosomes and Golgi apparatus), few and small lipid droplets, numerous pinocytotic vesicles and a very thin basal lamina. The next stage in adipocyte differentiation is a ‘dark pfreadipocyte’ showing a denser cytoplasmic matrix, reduced organelles and more abundant lipid accumulations. The pinocytotic vesicles are very numerous and the enveloping basal lamina is still thin. The subsequent maturation stages are the well-known globular multivacuolated adipocyte and finally the mature univacuolated, signet-ring, white adipocyte.
Endotemporal Branching of the Facial Nerve
Authors: Djerić Dragoslava , Savić Dragoslav
Published: July 2008

Out of 400 specimens of temporal bone the authors found two cases of branching of the facial nerve in the mastoid course, i.e., 0.5%. Knowledge of this anomaly has a certain practical value in surgical intervention of the middle ear.
Aminergic Innervation Pattern of the Rodent Pineal Gland: No Apparent Influence of Time of Day
Authors: Schroder Hannsjörg
Published: July 2008

Pineal melatonin synthetic activity shows distinct diurnal characteristics. The circadian regulation of melatonin synthesis is provided by nor adrenaline-releasing sympathetic nerves. The pineal nor adrenaline content shows a circadian rhythmicity tidally related to the changes in melatonin synthesis rate. To evaluate possible circadian changes of pineal noradrenergic fibre arrangement, the nerve distribution in rat and guinea pig pineal glands was visualized by means of glyoxylic acid-induced histofluorescence. Histochemical findings at 08.00 h and 24.00 h did not exhibit any differences: in both species a dense, mainly perivascularly located network of fluorescent fibres was encountered. As indicated by the simultaneous intraneural presence of green-bluish and yellow fluorophores these fibres most likely contain nor adrenaline and serotonin. Obviously circadian melatonin synthesis changes are not paralleled by changes in the distribution pattern of pineal sympathetic nerve fibres. Like other sympathetic innervation-related morphological parameters, histofluorescence does not accurately reflect circadian biochemical changes in the pineal gland.
The Ground Reaction Force Pattern from the Hindlimb of the Horse Simulated by a Spring Model
Authors: van Gurp M. , Schamhardt H.C. , Crowe A.
Published: July 2008

A model consisting of a spring loaded by a time-dependent mass is presented simulating the vertical and longitudinal horizontal ground reaction force patterns obtained from the hindlimb of a walking horse.
Non-Pyramidal Neurons of Layers I–III in the Dog’s Cerebral Cortex (Parietal Lobe)
Authors: Ferrer Isidro , Sancho Sara
Published: July 2008

In an attempt to classify neurons in the upper layers of the cerebral cortex according to modern nomenclature based on Golgi impregnations, non-pyramidal neurons in layers II and III of the dog’s cerebral cortex have been categorized into thirteen types: (1) large double-bouquet cells with long ascending and descending axons (type I double-bouquet cells); (2) bipolar neurons; (3) multipolar neurons with long tufted descending axons (type II double-bouquet cells); (4) neurons with long ascending axons; (5) neurons with superficial axon plexuses; (6) elongated large multipolar neurons with extended generalized axonal arborizations; (7) neurons with long descending axons; (8) small bi-tufted neurons with short ascending, descending or local axons; (9) small multipolar neurons with short ascending, descending or local axons; (10) multipolar neurons with local or extended axonal arborizations usually forming arcades (some of them also with a long descending axon); (11) basket cells; (12) neurogliaform neurons, and (13) chandelier cells. Neurons in the molecular layer were horizontal cells and multipolar neurons with short axons. These data have been compared with those described in other species to provide a provisional classification of non-pyramidal neurons located in the upper layers of the cerebral cortex.
Immunohistochemical Studies on GABAergic Neurons in the Rat Locus coeruleus, with Special Reference to Their Relationship to Astrocytes
Authors: Iijima Koichi , Kobayashi Ryoji , Kojima Naosuke
Published: July 2008

Purified antisera against GABA were prepared. A few small GABAergic neurons in the rat locus coeruleus were immunohistochemically demonstrated by both the unlabeled peroxidase-antiperoxidase method and the avidin-biotin peroxidase complex method using affinity-purified GABA antibodies. The glial fibrillary acidic protein immunoreactivity in this nucleus was localized by the latter method in the astrocytal framework encircling medium-sized and small neurons as well as in straight processes. Astrocytes may play a role as energy donors to these neurons.
Ultrastructural Observations on the Gallbladder of Richardson’s Ground Squirrel (Spermophilus richardsonii)
Authors: Pemsingh R.S. , MacPherson B.R. , Scott G.W.
Published: July 2008

The gallbladder of Richardson’s ground squirrel shares many structural similarities with numerous other species, including the mouse, rabbit and man. Dark cells exhibit a condensed cytoplasm but contain all the typical organelles of light cells, although their total complement appears reduced. Edematous cells extruded from the epithelial lining were replaced through mitosis or had their space occupied by adjacent cells. Specializations of the basal plasma membrane and underlying basal lamina form peg-and-socket interdigitations, and desmosomes were observed on the lateral cell boundaries down to the level of the basal lamina. The latter remain intact during active water resorption while the former disappear. Adrenergic nerve fibers were observed intramuscularly and beneath the basal lamina. Random interepithelial migration of leucocytes was also observed. Some of these observations help to elucidate controversial issues whereas others have been previously unreported and may be species-dependent.
Quantitative Ultrastructural Study of Somatotropic Cells in Malnourished Weanling Rats
Authors: Dumm Cesar.L.A. Gómez , Pucciarelli Héctor M. , Dressino Vicente
Published: July 2008

A quantitative ultrastructural study of somatotropic cells was carried out in 21-day-old malnourished rats after maternal food restriction during the nursing period. Changes represented mainly by a reduced cytoplasmic mass and diminished secretory material were found. A decrease in growth hormone secretion of malnourished weanling rats is suggested.
Morphometry of Eosinophils in Human Blood
Authors: Sokol R.J. , James N.T. , Wales J. , Hudson G.
Published: July 2008

Ultrastructural characteristics of human blood eosinophils have been analysed by morphometric methods in 18 healthy adults. Data were obtained relating to whole cell, nucleus, mitochondria and specific granules. No significant differences were found between the eosinophils of the 9 male and 9 female subjects. The results provide normal values against which changes in eosinophils in disease states may be assessed.
Morphology of the Meniscotemporal Part of the Temporomandibular Joint and Its Biomechanical Implications
Authors: Bermejo-Fenoll A. , Puchades-Orts A. , del Campo Sanchez , Panchon-Ruiz A. , Herrera-Lara M.
Published: July 2008

The temporomandibular joint is a diarthrosis. It has classically been referred to as being a condylar, and functionally as a double condylar joint. We have used the moirÉ topographical technique to study the morphology of the pars suprameniscalis or meniscotemporalis of the joint. The findings show that this pars suprameniscalis could be classified as a saddle joint. The biomechanical implications are also discussed.
Immunoperoxidase Localization of Actin in Tomes’ Processes of Ameloblasts of Rat Incisor
Authors: Sandhu Harinder S.
Published: July 2008

Actin has been localized inTomes’ processes of the ameloblasts by the immunoperoxidase method using antiserum against purified rat actin. The zone of initial mineralization in dentin also gave a positive reaction. The possibility exists that actin may have a role in local accumulation of calcium during mineralization of various calcified tissues.
Effects of Mechanical Loads on Surface Morphology of the Condylar Cartilage of the Mandible in Rats
Authors: Bouvier Marianne , Zimny Marilyn L.
Published: July 2008

Mechanical loads on the condylar cartilage were varied by feeding either a hard diet, a soft diet, or a sequential combination of a soft diet followed by a hard diet to young male and female rats for a total period of 4 weeks, and to mature male rats for 12 weeks. Gross condylar dimensions were greatest in the hard-diet groups, intermediate in the combination soft/hard-diet groups, and smallest in the soft-diet groups. Scanning electron microscopy of the condyle revealed a smooth, nonporous articular surface in the soft-diet groups. Hard-diet condyles had a rougher, more porous articular surface while soft/hard-diet condyles were intermediate between nonporous and slightly roughened condyles. None of the condyles showed ridges or elevations on the articular surface. Sex, age and time of the diets did not significantly affect these results.
Forces Acting on the Patella during Maximal Voluntary Contraction of the Quadriceps femoris Muscle at Different Knee Flexion/Extension Angles
Authors: van Eijden T.M.G.J. , Weijs W.A. , Kouwenhoven E.K. , Verburg J.
Published: July 2008

From knee extension moments measured with a dynamometer, the quadriceps muscle force, the patellar ligament force and the reaction force in the patellofemoral joint at various knee angles (0–90°) were estimated. The information needed to calculate the combined effect of both patellofemoral and tibiofemoral joint on the mechanical advantage of the muscle was obtained from lateral-view radiographs of autopsy knees.The results show that the smallest quadriceps force (2,000 N) is exerted at maximal extension, and the largest force (8,000 N) at about 75° of flexion. The patellar ligament force reaches a maximum (5,000 N) at 60°. The reaction force in the patellofemoral joint is the smallest (1,000 N) at extension and is of the same values as the muscle force in a range from 75 to 90°. Especially at large flexion angles, the value of the estimated forces is considerably larger (by 100%) than reported in the literature. This difference is attributed to the influence of the patellofemoral joint on the mechanical advantage of the muscle, which has not been taken into account in other studies.
Comparative Study of Interstitial Cells of Cajal
Authors: Faussone-Pellegrini Maria-Simonetta
Published: July 2008

The cells present in the alimentary canal, contacting both nerve endings and smooth muscle cells and named interstitial cells of Cajal, show different ultrastructural features. A comparative study has been performed in order to see if these differences can be related to the animal species studied or to the interstitial cell localizations inside the muscle wall of the various levels of the alimentary canal or to their contacts with other cells. Only mammals were considered, and rat, mouse, hedgehog and man have been studied. All the localizations where interstitial cells of Cajal have usually been found were considered: esophagus (body and lower sphincter), stomach (gastric extent of the lower esophageal sphincter, fundus and corpus) small intestine and colon. From this comparison a correlation was found between the morphology and the location of interstitial cells. On the contrary, the morphological differences existing between animal species do not seem to be that consistent. Moreover, the number of contacts between interstitial cells and between these and smooth muscle cells and nerve endings varies according to the interstitial cell location and morphology. It is concluded that the chain nerve endings → interstitial cells of Cajal → smooth muscle cells is not morphologically identical at each gastrointestinal level, and this finding is considered very important in interpreting the role played by the interstitial cells of Cajal in gastrointestinal motility.
Microvascular Architecture of the Mucosa of the Gastric Corpus in Man
Authors: Raschke M. , Lierse W. , Van Ackeren H.
Published: July 2008

Vascular casts of human gastric mucosa of the corpus area were studied by scanning electron microscopy and compared with vertical and horizontal series of semithin sections of perfusion-fixed corpus mucosa.The submucosal arteries give off short and long arterioles. The short arterioles branch into a basal capillary network reaching from the basis to the isthmus of the gastric glands.The long arterioles pass through the lamina propria without ramifications and supply a second, apical capillary layer reaching from the base to the top of the gastric pits. Anastomoses connect both capillary layers. Dense, convoluted capillaries at the mucosal surface encircle the gastric pits. Both capillary layers drain into venules at the level of the gastric pits. Below, on their way to the submucosal plexus, the venules do not receive any further capillary tributaries. In the examined tissue no arteriovenous anastomoses could be identified. A microvascular architecture with two capillary layers is presented, which guarantees a luxurious oxygenation throughout all layers of the gastric corpus mucosa in man. These findings are in contrast to previous descriptions of human corpus mucosa, where only one capillary layer, reaching from the base to the top of the corpus mucosa, has been identified.
Axiale Mesenchymstrukturen in der Anlage der Halswirbelsäule des Menschen
Authors: Strasmann Thomas
Published: July 2008

The anlage of the cervical vertebral column of a human embryo has been investigated (9 mm CRL, Carnegie stage 16). The nuclear density in the axial mesenchyme increases rhythmically from cranial to caudal. This phenomenon superimposes a metameric pattern on the blastema. Furthermore, cell formations are shaped by the orientation of the mesenchymal cells. The name ‘formationes quasi distensae’ is proposed for this system. The anlage of the atlas shows a distinct mesenchymal anlage of a vertebral body. The conclusion is drawn that the dens axis is predominantly formed out of the anlage of the atlas body. The opinion that man does not show an anlage of the atlas body can no longer be sustained.