bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of Transforming Growth Factor-Beta on Insulin-Like Growth Factor 1- and Dexamethasone-lnduced Proliferation and Differentiation in Primary Cultures of Pig Preadipocytes
Authors: Richardson R.L. , Hausman G.J. , Gaskins H.R.
Published: July 2008

The purpose of this study was to examine the effects of a known inhibitor, transforming growth factor-β1 (TGF-β1) versus the known stimulators insulin-like growth factor-1 (IGF-1) and dexamethasone (DEX) on pig preadipocyte differentiation in serum and serum-free primary cultures. In cultures with serum, preadipocyte and nonpreadipocyte replication was increased (p < 0.02) by IGF-1 and by TGF-β1 (p < 0.05; p < 0.001). IGF-1 (10 nM) enhanced preadipocyte differentiation (p < 0.05) in serum-supplemented (1% pig serum) cultures, whereas TGF-β1 (15 pM) reduced preadipocyte differentiation (p < 0.01) in the presence and absence of IGF-1. Furthermore, GPDH (SN-glycerol-3-phos-phate dehydrogenase) specific activity (marker that indicates differentiation) was decreased (p < 0.05) by adding TGF-β1to serum-free cultures, but TGF-β1 had little effect in serum-supplemented cultures. DEX significantly enhanced GPDH activity and fat cell cluster number, whereas pretreatment with TGF-β1· eliminated the DEX enhancement. We have shown for the first time that TGF-β1 can decrease (p < 0.01) the cellular secretion of IGF-1 by pig adipose tissue cells and counter the effects of exogenous IGF-1. These studies indicate that TGF-β1 may not inhibit adipocyte development in the initial growth phase, but may inhibit differentiation and/or hypertrophy (lipid filling) at a later stage of development.
Zur Gefässversorgung des Plexus brachialis
Authors: Klaus B. , Hose U. , Lierse W.
Published: July 2008

The blood supply of brachial plexus is described by means of lightened injected specimens of older human fetus. The following arteries have direct branches to brachial plexus: the aortic arch/brachiocephalica trunk, subclavia a., thyrocervical trunk, ascending cervical a., transverse cervical a., suprascapular a., and the acromial network. Secondary branches leave them that partly anastomose and also return from distal to proximal. The blood supply is luxurious.
Anatomy and Function of the Bursa subacromialis
Authors: Birnbaum K. , Lierse W.
Published: July 2008

The ligamentum coracohumerale, as the anterior limit of the bursa subacrot sialis, runs into the shoulder joint capsule, connecting – broadly based – above the sulcus intertubercularis. It does not, however, originate – as described previously – from the base of the processus coracoideus (viewed frontally), but rather medially from the base, i.e. on the side of the fossa supraspinatus. The sliding mechanism starting at 50° affects the parietal sheet of the bursa subacromialis, whereby the laterally situated section slides under the medially situ; îed section. With an abduction of up to 50°, the lateral section congests in froti of the corner of the acromion, sliding from there under the acromion, so that the – hitherto – medial section is located above the section now sliding away beneath it. This sliding mechanism continues on up to 100°. At this point the parietal sheet of the bursa subacromialis lies as follows: The section that had been situated laterally at the beginning of the sliding mechanism now lies caudally to the section that had lain medially at the outset. The bursa subacromialis does not slide fully into the fossa supraspinatus, as in all of the cases observed, it is firmly connected, together with the fascia subdeltoidea, to the corner of the acrom > n. The visceral sheet does not change in the course of the sliding mechanism as described, as it is connected to the fascia of the supraspinatus muscle – with the exception of a medial stretch of 16 mm. A further finding deals with the course of the muscles of the caput breve of the biceps brachii. Individual muscle fibre components do not connect to the processus coracoideus, but rather run before the tip of the processus coracoideus into the ligamentum coracoacromiale, radiating not only into the ligamentum coracoacromiale, but also – certain components – into the shoulder joint capsule. Through this, the ‘aponeurosis tendinis brachii’ forms a tendon roof in front of the processus coracoideus that extends to the structures running along the head of the humerus. The muscle fibre components of the caput breve of the m. biceps brachii radiating into he shoulder joint capsule, together with the muscles of the rotator cuff and the ligamentum coracohumerale, keep the shoulder joint capsule tense, thus prevent ng constriction symptoms.
Specialized Cell Contacts in the Developing Nerves of Mouse Embryos
Authors: Bogusch G.
Published: July 2008

In mouse embryos, special focal contacts between axons and Schwann cells, axons and fibroblasts as well as Schwann cells and fibroblasts are visible during the outgrowth of nerves. These rather seldom contacts exhibit a uniform structure. Axons and Schwann cells form small finger-like protrusions projecting into coated pits of Schwann cells and fibroblasts. The narrow intercellular space in the contact zone is crossed by fine filaments.
‘Synaptic Ribbon’ Modifications in the Pineal Gland of the Albino Rat Following 24 Hours of Immobilization
Authors: Soriano Martinez , de Tejada Hernandez Gil , Herrador Sanchez , Tomer Ruiz
Published: July 2008

We have studied the ultrastructure of the pinealocyte after 24 h of immobilization. Thirty male albino rats (230 ± 10 g) were used; the animals were divided into two groups of 15 each. One group was immobilized for 24 h (10.00 h a.m. to 10.00 h a.m.), whereas the other group was used as control. All animals were sacrificed between 10.00 and 14.00 h of the following day. Ultrastructural observations showed an euchromatinic nucleus with numerous giant ‘lipid droplets’ as well as abundant long ‘synaptic ribbons’ that were significantly more abundant than in the controls (p < 0.0005). These findings all suggest an increase in pineal activity following 24-hour immobilization.
Distribution of Extracellular Matrix Components during Early Embryonic Development in the Macaque
Authors: Peterson P.E. , Pow C.S.T. , Wilson D.B. , Hendrickx A.G.
Published: July 2008

The distribution of fibronectin (FN), laminin (LM), hyaluronic acid (HA) and chondroitin sulfate (CS) were examined by peroxidase immunocytochemistry in long-tailed monkey embryos during the period of neural tube and notochord formation (stages 8-11). Reactivity for each component in the neuroepithelial basement membrane (BM) increased with advancing development. Discontinuous staining was observed in areas of epithelial-to-mesenchymal transformation, i.e. in dorsolateral sites of neural crest emigration and in the axial region of the primitive streak. The BM forming around the developing notochord also showed increased reactivity for FN, LM, HA and CS between stages 8 and 11. No staining occurred within the notochord. Stage-related increases in reactivity in the mesenchymal matrix was particularly notable for FN and HA which were ubiquitous throughout the mesoderm by stage 11. The results of this study are consistent with the proposed role of these components in maintaining epithelial integrity and providing a permissive substrate for cell migration during development. The observed temporal and regional staining patterns suggest that these glycoproteins and glycosaminoglycans are important morphogenetic factors in the macaque.
Nerve Terminals Associated with the Central Lacteal Lymphatics in the Duodenal and lleal Villi of the Monkey
Authors: Ichikawa S. , Kyoda K. , Iwanaga T. , Fujita T. , Uchino S.
Published: July 2008

An intimate association of nerve fibers with the central lacteal endothelium was demonstrated in the duodenum and ileum of the monkey by immunohistochemistry and transmission electron microscopy. In the basal portion of the central lacteal, nerve fibers containing large cored vesicles and small clear vesicles were located closely beneath the lacteal endothelium. Identification of nerves was performed by immunohistochemistry using antisera against substance P (SP), calcitonin gene-related peptide (CGRP), vasoactive intestinal polypeptide, gastrin-releasing peptide and neuropeptide Y. These nerves contained immuno-reactivities for SP and CGRP only. Some of the nerves, either singly or in a dense bundle, indented the endothelial cells to form a conspicuous cushion protruding into the lumen. The attenuated endothelium covering the cushion occasionally was failing, and the nerves were exposed to the lumen. Tight of occasionally subendothelial nerve terminals bundles formed a synapse-like association between themselves: a swollen axonal profile was invaginated by a fingerlike projection of another axon, the latter being filled with synaptic vesicles. These results suggest that the central lacteal lymphatics might be afferently monitored, presumably with regard to the luminal pressure, and, at the same time, efferently modulated by these nerves.
Morphological Evidence for a Cecocolonic Junction in Man and Functional Implications
Authors: Faussone-Pellegrini M.-S. , Pantalone D. , Cortesini C.
Published: July 2008

The region above, below and in front of the ileocecal valve opening has been studied in man using both light and electron microscopy. A cecocolonic junction, comprising the colonic basal portion of the ileocecal valve, could be demonstrated in man, due to the specific anatomy of the inner portion of the circular muscle. This muscle was arranged in anastomosing cords, richly innervated and enveloped by elastic fibers. Its smooth muscle cells were characterized by extremely wide sarcoplasmic cisternae and cell-to-cell junctions, numerous caveolae and large amounts of glycogen. Interstitial cells were rarely found. This junction might be considered responsible for (1) ileal flow accommodation, (2) colonic active movements and (3) ileocecal valve closing and opening.
Innervation of the Human Adrenal Cortex: Simultaneous Visualisation Using Acetylcholinesterase Histochemistry and Dopamine β-Hydroxylase Immunohistochemistry
Authors: Gilchrist A.B. , Leake A. , Charlton B.G.
Published: July 2008

The inter-relationship between putative cholinergic and noradrenergic innervation of the human adrenal cortex was investigated using a technique which combined acetylcholinesterase histochemistry, choline acetyltransferase radio-chemistry and dopamine β-hydroxylase immunohistochemistry. Cholinergic and noradrenergic nerve fibres had a near-identical distribution, with varicose noradrenergic fibres located immediately alongside non-varicose cholinergic nerve bundles in all cortical zones. Choline acetyltransferase activity was consistently detected in the adrenal cortex, confirming the presence of cholinergic neurons. It is postulated that noradrenergic innervation has a role in the modulation of cortical endocrine secretion, while cholinergic nerves are mainly concerned with the control of medullary secretion.
Accessory Oculomotor Nuclei of Man
Authors: Bianchi R. , Gioia M.
Published: July 2008

A morphoquantitative study was carried out to clarify the cytoarchitecture of the human nuclear complex of the posterior commissure (NPC), a collection of cell groups which is thought to be involved in the pupillary light reflex and eye movements. On the basis of the topographical features, 5 different parts (rostral, principal, magnocellular, subcommissural and infracommissural) were identified in NPC. In these 5 parts, the neuronal population consisted of small and medium-sized neurons with a structural pattern similar to that of the central reticular formation. The only exception was the magnocellular part in which the neurons, mainly medium-sized and large, did not show the reticular-like features. In the Golgi material, two types of NPC neurons were identified: multipolar and fusiform cells. In the multipolar cells, 2-3 dendrites emerged from the soma and gave off a wide dendritic arborization. Many of the dendrites and axons of the multipolar cells were seen spreading outside NPC. The fusiform cells had 2 dendrites emerging from the opposite poles of their elongated perikaryon. Dendrites and axons of the fusiform cells always lay inside NPC. These observations suggest that the multipolar cells are mainly projective neurons and that the fusiform cells are neurons which mainly perform a local integrative function. Since the present study concludes our investigation of the human accessory oculomotor nuclei, a comparison of their structure was carried out. All the nuclei showed a common reticular-like structure, although each nucleus had its own structural particularities. These results are in agreement with and give an anatomical support to the functional findings.
Ramification of the Intercostal Nerves in the Rhesus Monkey (Macaca mulatta) with Special Reference to the Innervation of the Intercostal Muscles
Authors: Sakamoto H. , Akita K. , Sato T.
Published: July 2008

Detailed dissection was performed on the ventral primary rami from the first thoracic to the second lumbar nerves in order to obtain more comprehensive data of the ramification of the intercostal nerves in the rhesus monkey. The nerves to the intercostalis intimus and internus and the obliquus externus abdominis tended to arise as a common trunk from the main intercostal nerve. A comparison of the intercostal nerve ramification with that in man is included.
Stride Characteristics of Overground versus Treadmill Locomotion in the Saddle Horse
Authors: Barrey E. , Galloux P. , Valette J.P. , Auvinet B. , Wolter R.
Published: July 2008

The purpose of this study was to compare the velocity-dependent changes in stride length and stride frequency of horses performing the same incremental exercise test first on a track with a rider and then on a treadmill with a 0 and 3.5% slope successively. Seven French saddle horses undertook the exercise test which consisted of 5 stages of increasing speed for 3 min each with 1 min rest between each stage (1.6, 4.2, 8.3, 9.2 and 10 m/s). The horses were recorded by use of a video camera, and the tapes were analysed with regard to gait parameters. At 1.6, 8.3, 9.2 and 10 m/s, stride frequencies were significantly (p < 0.01) greater on the track than on the treadmill. At the walk, stride length was significantly (p < 0.01) shorter on the track than on the treadmill. There were strong linear relationships between stride length and speed in all experimental conditions (R2 > 0.96). The comparison of the regression coefficients revealed significant differences (p < 0.01) between track and treadmill locomotion; stride length was longer on both the horizontal and inclined treadmill than on the track. The incline of the treadmill did not significantly (p > 0.01) influence stride parameters.
Multi-Body Modelling and Simulation of Animal Locomotion
Authors: Van den Bogert A.J , Schamhardt H.C.
Published: July 2008

Multi-body models of musculoskeletal systems can be used to determine internal forces from measured external forces and movements (‘inverse dynamics’) and to perform simulations of movements using muscle forces or activations as input (‘direct dynamics’). Examples of ‘direct’ simulations of movements in the horse are presented. With a model of the equine hindlimb, the function of the ‘passive stay apparatus’ could be explained. A model of the forelimb was used to determine force distributions in the digital flexor tendons, and to experiment with various methods to change the force distribution. Simulations of this type are valuable tools in basic research on functional anatomy and aetiology of injuries. An application with much future potential is the optimization of sports performances using simulation methods.
Recommended Terminology for Researchers in Locomotion and Biomechanics of Quadrupedal Animals
Authors: Leach D.
Published: July 2008

This paper summarizes recommendations for terminology to be used in the description of quadrupedal locomotion and selected aspects of biomechanics. Directional terms and planes of the body (anatomical position, spatial reference systems), joint angulation, conformation, general locomotion terminology, phases of the stride and limb cycle (e.g. step, cadence) and terminology for the description of jumping are described.
Application of TrackEye® in Equine Locomotion Research
Authors: Drevemo S. , Roepstorff L. , Kallings P. , Johnston C.J·
Published: July 2008

TrackEye® is an analysis system, which is applicable for equine biokinematic studies. It covers the whole process from digitizing of images, automatic target tracking and analysis. Key components in the system are an image work station for processing of video images and a high-resolution film-to-video scanner for 16-mm film. A recording module controls the input device and handles the capture of image sequences into a videodisc system, and a tracking module is able to follow reference markers automatically. The system offers a flexible analysis including calculations of markers displacements, distances and joint angles, velocities and accelerations. TrackEye was used to study effects of phenylbutazone on the fetlock and carpal joint angle movements in a horse with a mild lameness caused by osteo-arthritis in the fetlock joint of a forelimb. Significant differences, most evident before treatment, were observed in the minimum fetlock and carpal joint angles when contralateral limbs were compared (p < 0.001). The minimum fetlock angle and the minimum carpal joint angle were significantly greater in the lame limb before treatment compared to those 6, 37 and 49 h after the last treatment (p < 0.001).
Quantification of the Locomotion of Dutch Warmblood Foals
Authors: Back W. , van den Bogert A.J. , van Weeren P.R. , Bruin G. , Barneveld A.
Published: July 2008

To get an in-depth insight into the ontogeny of the equine locomotor apparatus, the locomotion of 28 Dutch Warmblood foals was recorded at the walk, trot and canter on a treadmill using a CODA-3 apparatus. A great similarity in joint angle-time diagrams was found, although considerable differences in kinematic gait parameters of individual foals could be detected. These results contribute to an objective comparison of the locomotor performance of foals.
Surface Strain on the Dorsal Metacarpus of Thoroughbreds at Different Speeds and Gaits
Authors: Davies H.M.S. , McCarthy R.N. , Jeffcott L.B.
Published: July 2008

Stacked rectangular rosette strain gages were used to measure surface bone strain on the dorsomedial cortex of the third metacarpal bones in 6 adult Thoroughbred horses during treadmill exercise. The peak principal compressive and tensile strains, angle of the peak strains and strain rate during loading were calculated and compared with speed and gait. At speeds from 4 to 14 m/s loading on the metacarpus resulted in compression of the dorsomedial cortex. Tension only occurred consistently in 1 forelimb of 1 horse at the walk (2 m/s). The angle of peak compression was within 10° of the longitudinal axis of the bone, and the magnitude of compression was proportional to the speed of exercise. Mean maximum compressive strains in the 6 horses at 2 m/s were –668 µstrain, –1,204 µstrain at 4 m/s; –1,617 µstrain at 6 m/s; –2,127 µstrain at 8 m/s, and –2,533 µstrain at 10 m/s. Recordings from 3 horses gave a mean –3,206 µstrain at 12 m/s, and strains at 14 m/s approached –4,000 µstrain. Peak strains were similar in both forelimbs at the canter while strain rate tended to be higher in the leading forelimb.
Quantification of Hind Limb Lameness in the Horse
Authors: Buchner F. , Kastner J. , Girtler D. , Knezevic P.F.
Published: July 2008

The three-dimensional optoelectronic locomotion analysis system SELSPOT II was used for kinematic studies of hind limb locomotion patterns. Two groups, 11 sound horses and 15 horses suffering from hind limb lameness, were examined at the trot. Both graphical and quantitative analyses were compared in sound and lame horses. The parameter hip acceleration quotient (HAQ), using the different peaks of vertical acceleration of one hip during one stride, proved to be a suitable value for quantitative analysis of hind limb lameness. In sound horses the HAQ ranged from 1.03 to 1.54, lame horses showed values between 1.32 and 2.96. Checking and documentation of diagnostic anesthesias or therapies are possible applications.
Relationships between Locomotor Forces, Hoof Position and Joint Motion during the Support Phase of the Stride of Galloping Horses
Authors: Ratzlaff M.H. , Wilson P.D. , Hyde M.L. , Balch O.K. , Grant B.D.
Published: July 2008

Three methods were used simultaneously to determine the relationships between the vertical forces exerted on the hooves and the positions of the limbs and hooves at the times of peak vertical forces from 2 horses galloping on a track straightaway. Vertical forces were recorded from an instrumented shoe, fetlock joint motion was measured with an electrogoniometer and the angles of the carpus, fetlock and hoof were determined from slow-motion films. At hoof contact, the mean angles of the carpus and fetlock were 181-182° and 199-206°, respectively. Peak vertical forces on the heel occurred at or near maximum extension of the carpal and fetlock joints. Peak forces on the toe occurred during flexion of the fetlock joint and at mean hoof angles of 28-31° from the horizontal. The mean angles of the hoof from the horizontal at the time of heel contact were 6-7°. Hoof lift occurred at mean carpal angles of 173-174° and mean fetlock angles of 199-200°.
Functional Morphology of Force Transmission in Skeletal Muscle
Authors: Trotter J.A.
Published: July 2008

The work done by the contractile proteins of muscle in accelerating, decelerating, or maintaining the positions of skeletal elements requires the efficient transmission of tension across the surface membranes of the fibers. The most widely studied sites of tension transmission are the ends of muscle fibers where they contact either connective or epithelial tissues. In most animals, regardless of phylum, muscle fiber ends are characteristically folded, producing a junctional interface that significantly reduces the absolute value of stress applied to the cell membrane, insures that the principle stress vector at the cell membrane is shear rather than tension, and minimizes stress concentrations. The morphological and molecular similarities of muscle-tendon junctions (MTJs) in different animals suggest that the problem of creating a strong adhesive joint between a muscle fiber and a tissue of dissimilar physical properties is essentially the same for all muscles, and that the solution arose early in evolution. In addition to those muscle fiber ends that occur where fibers contact dissimilar tissues, there are intramuscular fiber terminations that consist either of folded cell-cell junctions similar to the fasciae adherentes of cardiac muscle, or of gradually tapering fiber ends. Both sorts of intramuscular ends occur in those vertebrate muscles in which the individual muscle fibers are too short to reach from the tendon of origin to the tendon of insertion. In series-fibered muscles in which the fiber ends are tapered, tension is transmitted from contractile proteins to endomysial collagen fibrils across the fiber membranes. The endomysium of such muscles is an essential series-elastic element. The existing evidence suggests that tension transmission is a general property of muscle cell surfaces, and that specific junctional morphologies are the results of dynamic interactions between muscle cells and the tissues to which they adhere.
Characterization of the Extracellular Matrix during Somitogenesis in the Long-Tailed Monkey (Macaca fascicularis)
Authors: Peterson P.E. , Pow C.S.T. , Wilson D.B. , Hendrickx A.G.
Published: July 2008

The composition of the extracellular matrix (ECM) associated with somitogenesis (stages 10–14) in the long-tailed monkey (Macaca fascicularis) was examined using peroxidase immunocytochemistry. A distinct temporal and spatial staining pattern was demonstrated for each component examined. Fibronectin (FN), laminin (LM) and hyaluronic acid (HA) were associated with the somite at each developmental stage, while no chondroitin sulfate (CS) staining was evident until stages 13/14. The basement membrane and matrix fibers linking the somites to the surrounding epithelia stained for FN, LM and HA. Localization of LM and HA between somite cells was observed at each stage, whereas FN and CS reactivity within the somitic tissue was only observed between sclerotome cells at stages 13/14. Whereas FN- and HA-positive fibers surrounded the unsegmented mesoderm, HA, and to a lesser extent LM, were located within the pre-somitic tissue. Comparisons are made with earlier studies conducted in rodent and avian embryos which indicate that these ECM components may play a regulatory role in primate somitogenesis.
Fine Structure of the Tapetum lucidum of the Paca Cuniculus paca
Authors: Braekevelt C.R.
Published: July 2008

The tapetum lucidum of the paca or spotted cavy (Cuniculus paca) has been studied by light and electron microscopy. The reflective layer in this species is a tapetum cellulosum situated in the choroid of the superior fundus. Posteriorly, the tapetum is composed of several layers of ovoid to flattened cells while peripherally the tapetum gradually thins down and disappears. Within the tapetal cells most cell organelles are located near the nucleus. The dominant feature of these cells is, however, a large accumulation of electron-dense rodlets which show a variety of sizes, shapes and orientations. These rodlets are the reflective material of the tapetum, and energy dispersive studies indicate that they are rich in sulphur. The diameter and spacing of these irregular rodlets is too varied to be consistent with the principles of constructive interference, and the tapetum in the paca is probably capable of only diffuse reflectance. The retinal epithelium over the tapetum is nonpigmented while in nontapetal locations it is normally pigmented.
Somatotopic Organization of the Axons Innervating the Superior Rectus Muscle in the Oculomotor Nerve of the Rat
Authors: Atasever A. , Durgun B. , Çelik H.H. , Yilmaz E.
Published: July 2008

It has long been known that the pupillomotor fibers have a localized course in the dorsomedial periphery through the subarachnoid portion of the oculomotor nerve. However we do not have detailed knowledge about the organization of the fibers innervating individual extraocular muscles. This subject is of clinical importance for locating the site of lesions in patients with partial oculomotor nerve palsies. In this study the peripheral course of the axons innervating the superior rectus muscle were studied in the subarachnoid portion of the oculomotor nerve of the rat by making multiple injections of horseradish peroxidase solution into the muscle and reacting the nerve with tetramethylbenzidine as a chromogen. Coronal sections of the nerve showed that the axons innervating the superior rectus muscle were localized in the dorsal part of the nerve. Within the precavernous portion these axons showed a wider distribution invading dorsomedial and dorsolateral parts of the nerve.
Morphologic Regions of the Multitendoned Extrinsic Finger Muscles in the Monkey Forearm
Authors: Serlin D.M. , Schieber M.H.
Published: July 2008

The macaque multitendoned extrinsic finger muscles – extensor digitorum communis, extensor digitorum quarti et quinti proprius, extensor digitorum secundi et tertii proprius, flexor digitorum superficialis and flexor digitorum profundus (FDP) – were studied to define their muscle fiber architecture, tendon structures, endplate bands and patterns of external and internal nerve branching. Muscle fiber architecture was then used to define regions in each muscle that might represent functional subdivisions. Only in the FDP were these regions innervated by primary nerve branches characteristic of neuromuscular compartments.
Distribution of Neural and Neural-Crest-Related Antigens in Human Dental Pulp by Immunohistochemistry
Authors: Lombardi T. , Fiore-Donno G.
Published: July 2008

Human teeth (formalin-fixed, demineralized and paraffin-embedded as well as frozen sections of human dental pulp) were examined by immunohistochemistry to detect the presence and distribution of a series of neural and neural-crest-associated antigens: S-100 protein, neuron-specific enolase (NSE), glial fibrillary acid protein (GFAP), myelin basic protein (MBP) and neurofilaments (NF). Although several experimental pieces of evidence support a neural crest derivation for dental papilla and odontoblasts with the histological method used in the present study, these structures were immunonegative for most of the markers employed in the present investigation. Indeed, mesenchymal cells as fibroblasts and endothelial cells were devoid of immunostaining. Schwann cells were strongly immunostained by S-100, NSE and GFAP. Nerve fibres running in the pulp showed a positive labelling for NF, S-100 and MBP antisera. It is concluded that the lack of labelling of pulp cells (excepting nerves) by the neural and neural-crest-associated antibodies could be due to a loss of capacity to express these antigens during differentiation. However, the possibility that these antigenic determinants are expressed but outside the limits of sensitivity of immunohistochemistry cannot be ruled out. Further studies, including molecular biology techniques, are required to clarify these alternatives.
Ultrastructure of Fetal Pars-tuberalis-Specific Secretory Cells under the Influence of Propylthiouracil and Thyroxine
Authors: Holbeck A. , Böckers T.M. , Wittkowski W. , Sourgens H.
Published: July 2008

The rat pituitary pars tuberalis (pt) is a functional and morphological unique component of the adenohypophysis. It mainly consists of specific secretory cells whose morphological and functional characterization is far from being complete. In this study the ultrastructure of fetal secretory pt cells developing under hypo- and hyperthyroid conditions was examined. Besides controls, young mature pregnant Wistar rats were treated with propylthiouracil (PTU) or thyroxine (T4). Areas of pt cells and of their nuclei were measured. Different cell organelles per cell were counted, and area densities of these organelles were determined. While the number of dictyosomes per cell area did not change, the area densities of long ribbons increased significantly in the experimental groups. Lysosomes and secretory granules, however, were found to be significantly diminished in pt cells of T4- and PTU-treated animals. The latter finding corresponds to earlier investigations when changes of the thyroid-stimulating-hormone-like immunoreactivity of fetal pt-specific cells were observed under the same experimental conditions. Results indicate that fetal pt-specific cells respond to changes of thyroid status in a manner different from pars distalis thyrotrophs. An interaction of pt-specific cells in thyroid regulation mechanisms is assumed.
A Histochemical Study of the Distribution of Acetylcholinesterase-Positive Nerves in the Goat Pancreas
Authors: Hiramatsu K. , Watanabe T. , Ohshima K.
Published: July 2008

The distribution of acetylcholinesterase (AChE)-positive nerve fibers in the goat pancreas was investigated with histochemical methods at the light- and electron-microscopical level. Intrapancreatic ganglia showing AChE activity were found in the interlobular connective tissue or between acini. AChE-positive nerve fibers were distributed in whole glands and formed perivascular and periinsular plexus. Terminals were identified in both the exocrine and the endocrine tissue. These observations make clear that the cholinergic system is involved in the regulation of both the exocrine and endocrine pancreas in the goat.
Midfacial Retrusion in Adult Brachyrrhine Mice
Authors: Lozanoff S.
Published: July 2008

The purpose of this study was to determine quantitatively whether the Br mouse displays craniofacial size and shape patterns indicative of midfacial retrusion. Fifteen craniometric variables derived from a total of 40 male and female Br mice were compared with an equivalent number of C3H/HeJ adult mice displaying normal murine craniofacial morphology. Univariate statistical analysis showed that Br crania were significantly smaller for all measurements as compared with the C3H/HeJ specimens. Multivariate analysis revealed that the pattern of measurement covariation differed significantly between the two samples. Results indicated that the midface was significantly shorter in length relative to the calvaria in mutant mice as compared with C3H/HeJ mice. Therefore, the sagittal midfacial growth trajectory is deficient in Br mice.
Study of Sympathetic Innervation of Cranial Bones by Axonal Transport of Horseradish Peroxidase in the Rat: Preliminary Findings
Authors: Herskovits M.S. , Hallas B.H. , Singh I.J.
Published: July 2008

This study performed by intraneuronal tracing directly demonstrates the presence of sympathetic postganglionic fibers in the cranial vault of the rat. Superior cervical sympathetic ganglia were injected with horseradish peroxidase (HRP), and after a 48-hour period, to permit anterograde axonal transport, the animals were sacrificed after in situ perfusion. An area of the calvaria that included portions of the frontal and parietal bones was fixed, decalcified and sectioned. HRP-containing axons were localized in the developing frontal and parietal bones of the calvaria. Adrenergic innervation was not demonstrated in sutural tissue (superior sagittal, coronal or metopic) by this technique. To our knowledge, this study is the first to trace sympathetic nerve fibers in the rat calvaria by intra-axonal transport of HRP.
Fibulo-Tibial Weight Index – A New Criterion for Sex Identification Based on the Lower Leg Bones
Authors: Sacragi A. , Ikeda T. , Terada H.
Published: July 2008

This study was designed in an attempt to determine whether the fibula can provide reliable information for sexing human bones, if measurements include tibial indices. Our results allow us to introduce a new criterion for sexing long bones: the fibulo-tibial weight index. Bone weight was determined, together with conventional measurements, such as maximum bone length and mid-shaft circumference. The materials consisted of dried tibiae and fibulae of 71 recently deceased Japanese males and 31 females. The mean value of the fibulo-tibial weight index was very significantly greater in females than in males. In discriminant analysis, the rate of correct sex discrimination was improved by the inclusion of the fibulo-tibial weight index.
Increase in RNA and Glycogen but Not in DNA in Developing Human Macrophages Proven by Integrating Microdensitometry
Authors: Sokol R.J. , Hudson G. , Wales J.M. , Goldstein D.J. , James N.T.
Published: July 2008

In order to quantitate DNA, RNA and glycogen contents of developing macrophages, blood monocytes were obtained from 19 healthy human subjects and examined after 0, 2, 4 and 6 days of suspension culture. Cytochemical staining was carried out by standard methods using Feulgen, cuprolinic blue and PAS. All specimens from all subjects were stained at the same time. Examination was carried out in an integrating microdensitometer, the staining intensities of individual cells being measured at appropriate wavelengths. Over the 6 days of culture, highly significant increases took place in RNA and glycogen, but no significant change was found in DNA content. These findings are taken to indicate that increased protein synthesis and the building up of fuel reserves are features of macrophage development but that S phase DNA replication does not occur.
Histotopographic and Ultrastructural Study on the Lymphatic Network of the Pancreas in the Guinea Pig
Authors: Bertelli E. , Regoli M. , Comparini L.
Published: July 2008

The localization of absorbing lymph vessels was studied in the normal guinea pig pancreas by light microscopy (serial semithin sections) and transmission electron microscopy (ultrathin sections). Absorbing lymph vessels were observed both in the interlobular and intralobular areas where they can be localized close to the adenomeres. Lymph vessels were also seen in the interlobular areas located next to the islets of Langerhans and to groups of endocrine cells (n = 8-10) not showing a vascular organization comparable with islets of Langerhans. All lymph vessels in the pancreas are absorbing lymph vessels, characterized by a very thin endothelial wall, anchoring filaments and the absence of a definitive basal membrane. Adjacent endothelial cells form end-to-end, overlapping and interdigitating intercellular junctions. Valves were present both in the interlobular and intralobular lymph vessels.
Apocrine Secretion in the Infraorbital Gland of the Japanese Serow, Capricornis crispus: A Scanning Electron-Microscopic Study
Authors: Atoji Y. , Yamamoto Y. , Suzuki Y.
Published: July 2008

The infraorbital gland of the Japanese serow was examined under the scanning electron microscope to clarify the nature of apocrine secretion. The size and number of apocrine blebs on secretory cells varied markedly from cell to cell; as the size of blebs increased, their numbers decreased. After pinching off of blebs, crown-shaped structures were retained on the remaining apical surface of secretory cells. Detached free blebs in the lumen were spherical in shape with smooth surfaces. Secretory cells having blebs of similar size formed small clusters in tubules, and these clusters consisted of cells without blebs, cells with small blebs, cells with medium-sized blebs and cells with large blebs. The present evidence obtained by scanning electron microscopy is very much in harmony with results obtained at the light-microscopic level in terms of the sizes and numbers of blebs during apocrine secretion. Moreover, our evidence suggests the capacity for production of variously sized blebs in secretory cells and the presence of segmentary differences, in terms of apocrine activity, in tubules.
Effects of Clomiphene Citrate on Vaginal Epithelium of Ovariectomised Rats
Authors: Terry V. , Murphy C.R. , Shorey C.D.
Published: July 2008

Scanning electron microscopy and light microscopy have been used to study changes to the vaginal epithelium induced by exogenous hormones and clomiphene citrate (CC) administered to ovariectomised rats. Oestrogen (E2) administration resulted in epithelial cell proliferation and keratinisation. The administration of the E2/anti-E2 CC also resulted in the stimulation of cell proliferation, but not to the extent produced by E2. Lack of keratinisation, a decreased number of epithelial layers and decreased epithelial height were viewed as non-oestrogenic, or retarded oestrogenic, effects of CC. Modifications to the surface of vaginal luminal cells were also apparent following CC treatment. Cell apices were raised and separated by prominent borders; the surface covering consisted of short bulb-tipped microvilli that clumped together to form rosettes. Individual, elongated microvilli were also evident. The results of this study indicate that CC has retarded oestrogenic actions, as well as a unique ability to alter cell and surface morphology to produce characteristics dissimilar to those seen after treatment with E2 and progesterone.
Effect of Maternal Phenobarbital Consumption on Muscle Development in Mice
Authors: Ihemelandu E.C.
Published: July 2008

The effect of prenatal exposure to phenobarbital on muscle development was determined in 4 muscles (biceps brachii, triceps brachii, soleus and cranial tibial) of 34 mice (16 males, 18 females) at 12 weeks of age. The control group received unadulterated food ad libitum throughout the period of study. The phenobarbital-exposed group received 3 g of phenobarbital per kilogram of food from gestation day 7 to 18 as the only source of food. Outside this period they received unadulterated food and water ad libitum. Each mouse was killed at 12 weeks of age. The muscle mass of control mice was significantly larger than that of the phenobarbital-exposed group in both sexes. The smaller muscle mass of the phenobarbital-exposed group as observed from the analysis of the soleus muscle was due to a smaller number of muscle fibres being present than in the control group, since the muscle fibre sizes were similar in both groups. This indicated that prenatal administration of phenobarbital inhibits normal hyperplasia of muscle fibres.
The Right Atrioventricular Valvular Apparatus in the Chick Heart
Authors: Cayré R. , Valencia-Mayoral P. , Coffe-Ramírez V. , Sánchez-Gómez C. , Angelini P. , de la Cruz M.V.
Published: July 2008

The purpose of this study was to describe the detailed anatomy and histology of the right atrioventricular valve apparatus in the chicken. Newborn and adult chicken hearts were studied by anatomic description, light and scanning electron microscopy, and histologic (Masson’s trichrome stain) and histochemical (Sirius Red stain) techniques. Our findings indicate the presence of an incomplete fibrous annulus, a great mural leaflet, and multiple microleaflets in the right atrioventricular apparatus of the chicken heart. The great mural leaflet, essentially muscular in structure, extended from the anterior and posterior juxtaseptal commissures and was subdivided into an anterior and a posterolateral region by the attachment of the anterolateral papillary muscle. The posterolateral region presented an intermediate cleft, subdividing this region into an anterior and a posterior portion. Multiple microleaflets, which adhered to the upper right side of the ventricular septum adjacent to the right atrioventricular orifice, inserted directly into the ventricular septum via short chordae tendineae, without papillary muscles. The microleaflets were composed of smooth subendocardial connective tissue, with varying amounts of type I, II and III collagen. In addition, we observed a central fibrous body, leading to fibrous continuity between the mitral and aortic valves and the mitral and right atrioventricular valves. An atrioventricular septum was also present. Our findings serve to further document the anatomical similarities and differences between the chick and human hearts: (1) the septal leaflet of the human tricuspid valve, similar to the septal microleaflets in the chick, attaches directly into the interventricular septum by means of chordae tendineae without papillary muscles; the difference lies, however, in that the chick heart has multiple microleaflets and bulges, whereas the human heart has only one leaflet; (2) the great mural leaflet of the chick, though it is muscular, is divided by the anterolateral papillary muscle into two regions, one anterior and one posterolateral, which are similar to the anterior and posterior triscuspid valve leaflets in the human; (3) the right atrioventricular annulus in the chick is incompletely analogous to that occasionally seen in the human heart, and (5) the central fibrous body and the atrioventricular septum are present in both species.
Studies of the Motoneurons Following the Injection of Horseradish Peroxidase into the Peripheral Branches of the Facial Nerve in Rats
Authors: Tsai T.C. , Wu C.H. , Wen C.Y. , Shieh J.Y.
Published: July 2008

With the method of retrograde transport of horseradish peroxidase, the present study demonstrated a topographical representation of the peripheral branches of the facial nerve within the rat facial nucleus. The labelled neurons relating to the different peripheral branches were characterized morphometrically with the aid of an image analyser system. While the results were in general agreement with the work of other investigators, a striking difference was observed in this study with respect to the spatial distribution of the labelled neurons of the cervical branch. In the latter, the cells of origin were derived from the dorsal parts of the lateral and intermediate division of the facial nucleus. The present study further demonstrated that the motoneurons giving rise to the respective peripheral branches of the facial nerve varied considerably in cell size. Thus, the neurons of the posterior auricular and the mental branches were significantly larger than those of the nasolabial and zygomatico-orbital branches. Another significant finding in this study was that the neurons supplying the mental branch were predominantly spindle-shaped. It is concluded that the heterogeneity in size and shape of the motoneurons in the facial nucleus is related to the topographical representation of the peripheral branches of the facial nerve.
An Accessory Flexor digitorum longus Muscle
Authors: Yüksel M. , Önderoğlu S. , Yener N. , Yüksel E.
Published: July 2008

An accessory flexor digitorum longus muscle (M. flexor digitorum longus accessorius) in a 60-year-old male cadaver was encountered during routine dissections in our laboratory. The muscle originated from the deep transverse fascia of the leg, covering flexor digitorum longus, flexor hallucis longus, and tibialis posterior muscles, and additionally from some fibres of these muscles. After the tendon of the muscle passed behind the medial malleolus, it inserted into the tendon of the flexor digitorum longus muscle where the latter separated into four digital tendons.
Cranial and Spinal Nerve Organization in Amphioxus and Lampreys: Evidence for an Ancestral Craniate Pattern
Authors: Fritzsch B. , Northcutt Glenn
Published: July 2008

The spinal nerves in amphioxus are compared with the spinal and cranial nerves in lampreys. The dorsal spinal roots in amphioxus are similar to the mixed sensory and motor dorsal roots of many cranial nerves in lampreys but not to the purely sensory dorsal spinal roots in lampreys and gnathostomes. Likewise, cranial nerves V, VII, IX and X in lampreys, and all spinal nerves in amphioxus, lack a separate ventral motor root which is a constant feature of all spinal motor roots in lampreys and other vertebrates. Based on these similarities and differences, it is proposed that cranial and spinal nerves in craniates are independently derived serial homologs of elements of an amphioxus-like ancestral pattern. Further evolution involved the addition of neural crest-derived ganglia to most cranial and all spinal nerves, and the addition of placodally derived ganglia to many cranial nerves. The possible homology of ocular motor nerves is discussed but cannot be resolved owing to the absence of these nerves in hagfishes, which are the only relevant outgroup.
Brainstem Organization and Branchiomeric Nerves
Authors: Wake D.B.
Published: July 2008

The branchiomeric portion of the vertebrate head represents a region of specialized function and, at the same time, a transition between head and body. Recent experimental work has called into question the ‘visceral’ nature of the branchiomeres, interpreting them instead within the framework of the segmentation of the body, as is seen clearly in rhombomeres. The vagus nerve is critical to our understanding of this region. It is usually viewed as a serial homologue of dorsal roots of spinal nerves, and the hypoglossal, with its several roots, has been seen as arising from associated ventral roots. The accessory is often considered to have been derived directly from the vagus, having become individuated in tetrapods in general and especially in amniotes. Work on amphibians is examined with respect to these issues, and within structuralist, functionalist and phylogenetic frameworks. The accessory in mammals and birds is a composite; the spinal motor nucleus, which can be traced at least to elasmobranchs, is distinctly different in origin from the more recently added bulbar portion, which is derived from the vagus. The spinal portion appears to have evolved independently of the system associated with branchially derived musculature. The hypoglossal is derived from ventral-column material, but it is not clearly associated with the vagus phylogenetically.