bluuebunny/crossref_metadata_2025 huggingface dataset:
The Surface Features of the Epithelial Lining of the Ducts of the Epididymis of the Ostrich (Struthio camelus)
Authors: Aire T. A. , Soley J. T.
Published: March 2003

The luminal appearance of the various ducts of the epididymis of the ostrich was studied by scanning electron microscopy in tissues fixed by immersion in glutaraldehyde. The ductal types were similar to those previously described for some other species of birds. Numerous short microvilli, as well as a single cilium, projected from the apical surface of the rete testis cell. The ciliated cells of the efferent ductules projected tufts of cilia into the ductal lumen, while the non‐ciliated cells bore short microvilli. The connecting and epididymal ducts were lined by a columnar cell type whose apical surface bore uniformly distributed microvilli and a single, centrally situated cilium. The spermatozoa found in all ducts of the epididymis bore a distal cytoplasmic droplet. This observation has implications for the maturational process in the ostrich spermatozoon in the epididymis. The surface features of the ducts, except for a few noteworthy differences, were generally similar to those previously described for the male domestic fowl, turkey and duck.
A Scanning Electron Microscopic Study of the Peritoneal Mesothelium Covering the Genital Tract and its Ligaments in the Cow
Authors: Yániz J. L. , Santolaria P. , Rutllant J. , López‐Béjar M. , López‐Gatius F.
Published: March 2003

This study was undertaken to describe the surface features of the peritoneal mesothelium covering the genital tract and adjacent ligaments of the cow during the oestrous cycle. The relationship between mesothelial surface and spermatozoa was also evaluated after intra‐uterine and intraperitoneal insemination. Surface features of mesothelial cells from 25 cyclic cows were examined by scanning electron microscopy and by image analysis. Presence of spermatozoa was evaluated by scanning electron microscopy in seven additional cows. In the external side of the infundibulum, the oviductal mucosa exceeds the free margin, forming a continuous band measuring 2.5–10 mm in width. This oviductal epithelium shows cyclical variations with a predominance of ciliated cells during the follicular phase. In respect of the mesothelium, no clear morphological differences were observed associated with the side of ovarian bursa (internal versus external), or with the phase of the oestrous cycle. Mesothelial cells covering the uterus and mesometrium have a higher microvilli density and length and a smaller cell surface area than in the oviduct and adjacent structures. The presence of solitary cilia in the mesosalpinx and mesotubarium superius (infundibulo‐cornual ligament) of some specimens was also observed . When samples were processed without post‐fixation in osmium tetroxide, a layer of amorphous material covered all surfaces. After intra‐uterine insemination of five cows, no spermatozoa were found on their peritoneal mesothelium. Numerous spermatozoa were found after intraperitoneal insemination being attached throughout mesothelial surfaces. These results indicate that there are morphological differences between regions, but no cyclic changes, in the surface features of mesothelial cells covering the genital tract and adjacent ligaments of the cow, and that spermatozoa can bind to mesothelial surfaces after intraperitoneal insemination.
Characterization of the Swimming Muscle of the Anchovy Engraulis anchoita (Hubbs & Martini 1935)
Authors: Devincenti C. V. , Díaz A. O. , Goldemberg A. L.
Published: March 2003

The lateral muscle characteristics of individual female anchovies (Engraulis anchoita) were studied by histochemical and ultrastructural techniques. Red, pink and white fibres were discerned on the basis of the activity of the metabolic enzymes succinic dehydrogenase, phosphorylase and myofibrilar ATPase, and the usage of Sudan and periodic‐acid Schiff staining techniques. Red fibres were located at the surface, white fibres deep inside and pink fibres in between. The red fibres appeared flattened or ribbon‐shaped in transverse section and they were located in rows separated by myosepta of connective tissue. The red and pink fibres were multi‐innervated whereas the white fibres were terminally innervated. The relative proportion of the red muscle increased toward the caudal region, the white muscle diminished toward that region, whereas the proportion of pink muscle did not vary according to region, being scarce throughout. The distribution of capillaries was also investigated, and as a result, the vascular supply proved to be scarce in both white and pink muscle.
A Quantitative Study of the Aorta of the New Zealand Rabbit (Oryctolagus cuniculus L.)
Authors: Dabanoğlu I.
Published: March 2003

Ten segments of the aorta of the rabbit were studied quantitatively. The thoracic and abdominal aorta of the rabbit were measured from proximal to distal and parallel to the reduced diameter, demonstrating a decreasing thickness of the tunica intima and tunica media that becomes physiologically apparent during adulthood in these commonly used laboratory animals. The ratio of intimal to medial thickness, multiplied by 100, was calculated and found to be between 2.56 and 3.74 for the thoracic aorta and 4.03 and 5.62 for the abdominal aorta of the rabbit. These findings are important for the better understanding of the development of atherosclerosis.
Immunohistochemical Localization of Neuropeptides in Bovine Pancreas
Authors: Myojin T. , Kitamura N. , Hondo E. , Baltazar E. T. , Pearson G. T. , Yamada J.
Published: March 2003

The occurrence and density of distribution of nerves and endocrine cells that are immunoreactive for neuropeptides in the bovine pancreas were studied by immunohistochemistry. The six neuropeptides localized were galanin (GAL), substance P (SP), methionine‐enkephalin (MENK), neuropeptide Y (NPY), calcitonin gene‐related peptide (CGRP) and vasoactive intestinal polypeptide (VIP). The exocrine pancreas was shown to have an appreciable number of GAL‐ and SP‐immunoreactive nerve fibres but few fibres showing immunoreactivity for VIP and CGRP. Numerous MENK‐, GAL‐, SP‐, and NPY‐immunoreactive nerve fibres were seen in the endocrine portion of the pancreas. Nerve cell bodies in the intrapancreatic ganglia showed immunoreactivity for all of the neuropeptides except CGRP. Endocrine cells showing immunoreactivity for GAL and SP were observed in the large islets and islets of Langerhans, respectively. The present results indicate a characteristic distribution of neuropeptides in the bovine pancreas, which may regulate both exocrine and endocrine secretions of pancreas.
Aspects of the Functional Morphology of the Ductus Epididymidis in Domestic Anseriform and Galliform Birds
Authors: Aire T. A.
Published: March 2003

The structure of the ductus epididymidis, and its capacity to take up luminal particulate material (India ink) were studied, using scanning and transmission electron microscopy, in the domestic fowl, turkey and Japanese quail (Order Galliformes) and drake (Order Anseriformes). The epithelium appeared contractile and stable structurally, especially in the drake in which, among other cytoskeletal features, abundant perinuclear intermediate filaments radiated peripherally in the principal, non‐ciliated (Type III) cell. The Golgi complex was well developed, except in the turkey in which it was extremely inconspicuous. Sparsely granulated profiles were the main component of the elaborate endoplasmic reticulum, which was best developed in the drake and least in the turkey. The cell in the turkey was uniquely laden with large aggregates of lipid droplets. Generally, characteristics of a cell active in the synthesis and merocrine secretion of proteinaceous material were evident. There was no evidence of apocrine‐like secretion in well‐fixed tissues. The cell lacked the capacity to take up luminal India ink particles, and displayed very poorly developed endocytic structural features, which are also probably only selectively and minimally absorptive. Ultrastructural features varied between and within the orders studied, necessitating further studies.
Darstellung der Nerven am Flügel von Psittaciden (Amazone, Graupapagei) mit digitaler Phototechnik †
Authors: Hummel G. , Wenisch S. , Hörter‐Schmidt U.
Published: March 2003

Representation of the nerves of the wings in the blue‐fronted Amazon and the African grey parrot using a digital photographic technique

In four blue‐fronted Amazon and five African grey parrots, the nerves innervating the muscles of the wings were carefully dissected and described. The preparation steps were recorded with a digital camera. This technique has now advanced so far that the image quality is almost the same as that of a normal camera. The pictures are stored in a computer. They can be enhanced and published via the Internet.
Growth‐Promoting Effects of Different Fractions of Extra‐Embryonic Coelomic Fluid on Embryonic Development
Authors: Karabulut A. K. , Layfield R. , Pratten M. K.
Published: March 2003

In the early stages of embryonic development, many growth‐promoting molecules must be provided by the maternal system. These factors may be supplied locally to the embryo, by the decidua, the placenta, or the yolk sac. In this study the growth‐promoting potential of extra‐embryonic coelomic fluid (EECF) and its fractions was investigated. The embryonic requirement of growth‐promoting molecules may be studied by reducing the growth‐supporting capacity of serum. Thus, ultrafiltration of rat serum was carried out for 8 h using Millipore filters with a molecular weight exclusion of 30 kDa. Rat embryos at 9.5 days of age were cultured for 8 days for anembryonic yolk sacs, and then EECF was collected and divided into three different molecular weight fractions by ultrafiltration. Rat embryos were cultured for 48 h in whole rat serum and the serum retenate (which has low growth‐supporting capacity) in the presence and absence of EECF, its fractions, or in EECF only. Embryos grown in retenate showed severe growth retardation, and the addition of EECF significantly improved embryonic growth. The fraction which contained the molecules with molecular weight between 10 and 30 kDa had significantly more effect on embryonic development than the other fractions. This fraction of EECF was analysed by gel electrophoresis. Three of the four protein bands observed in this fraction were identified by amino‐terminal sequencing as α‐fetoprotein precursor (22 kDa), apolipoprotein A1 precursor (24 kDa) and fetal haemoglobin Y2 chain (14 kDa), none of which are likely to be responsible for the growth‐promoting activity. To further investigate growth‐promoting proteins, EECF was Western‐blotted to nitrocellulose membranes and probed with antisera against rat prolactin, epidermal growth factor, insulin‐like growth factors I and II and human placental lactogen. No immunoreactive bands were detected in the EECF, suggesting that either these proteins are not present or are present at levels too low to be detected. Although the growth‐promoting effect of the EECF was demonstrated in this study, the molecules responsible remain uncharacterized.
Has Active Immunization Against Gonadotrophin‐Releasing Hormone any Effect on Testis Innervation in the Pig? – An Immunohistochemical Study
Authors: Sienkiewicz W. , Molenaar G. J. , Kaleczyc J. , Falkowski J. , Lakomy M.
Published: March 2003

The innervation of porcine testes was studied in intact animals and in boars undergoing active immunization against gonadotrophin‐releasing hormone (GnRH) by means of immunohistochemistry using antibodies to tyrosine hydroxylase (TH), dopamine β‐hydroxylase (DβH), vasoactive intestinal polypeptide (VIP), neuropeptide Y (NPY), synaptosome‐associated protein of 25 kDa (SNAP‐25) and protein gene product 9.5 (PGP 9.5). Moreover, the distribution of luteinizing hormone (LH) receptors in clusters of Leydig cells was also investigated. To identify these cells easily, either the NADPH‐diaphorase histochemical technique or the Mayer counter‐staining procedure was applied. Differences in the distribution pattern and relative density of particular subsets of intratesticular nerve fibres were observed in immunized boars as compared to those found in the intact animals. In the testes of non‐treated animals, only single TH‐immunoreactive (TH‐IR) nerve fibres were observed. However, many DβH‐IR nerve terminals surrounded blood vessels in the tunica albuginea and parenchyma. Very scarce VIP‐IR nerves occurred only in the tunica albuginea, mainly in close vicinity to blood vessels. Immunoreactivity to NPY occurred in single nerve fibres. Immunoreactivity to SNAP‐25 and PGP 9.5 was found in single nerve fibres distributed mainly in the tunica albuginea. The interstitial cells were heavily stained for LH‐receptors and NADPH‐diaphorase. In the testes of immunized animals, only single TH‐IR nerve fibres, scattered mainly in the tunica albuginea, were observed. Some TH‐IR nerve terminals were also encountered in the parenchyma of the organ, where they were always associated with blood vessels. DβH‐IR nerve fibres formed a dense network distributed throughout the testis in association with the capsule, vasculature and interstitium. Some fibres were observed to run between seminiferous tubules. VIP‐IR nerve fibres were located in the neighbourhood of blood vessels in the tunica albuginea and parenchyma. Only single VIP‐IR nerves were found between seminiferous tubules. Numerous NPY‐IR nerve fibres occurred in the tunica albuginea and parenchyma of the organ. SNAP‐25‐IR and PGP 9.5‐IR nerve terminals formed a dense network distributed throughout the testis and many fibres were observed between seminiferous tubules. Interstitial cells were very weakly stained for LH receptors or NADPH‐diaphorase.
The Ultrastructure of the Subcommissural Organ Ependyma of the Goat
Authors: Kumar P. , Kumar S.
Published: March 2003

The cells of pseudostratified columnar ciliated ependyma of the subcommissural organ in the goat were classified into two types on the basis of the distribution of chromatin material and nuclear clefts. Amongst the cell organelles the endoplasmic reticulum was highly developed and formed three types of Nebenkerne systems. The type‐I Nebenkerne had spiral concentric lamellae and was associated with round lipid droplets. The type‐II Nebenkerne, with widely spaced coils, was expanded towards its central and peripheral parts. The type‐III Nebenkerne, composed of a meshwork of lamellae, was modified into a vacuolated form. The concentration of mitochondria was greatly increased towards the basal processes of the ependymal cells. The inclusion bodies included small electron‐dense bodies, osmiophilic asteroid droplets, large round to spherical bodies and large round osmiophilic bodies with inner structures.
Immunohistochemical Localization of Inhibin and Steroidogenic Enzymes in the Ovary of Common Tree Shrew (Tupaia glis) and Northern Smooth‐tailed Tree Shrew (Dendrogale murina)
Authors: Kimura J. , Tsukise A. , Watanabe G. , Taya K. , Rerkamnuaychoke W. , Endo H. , Kurohmaru M. , Yamada J. , Nishida T.
Published: March 2003

To study the ovarian function of the Order Scandentia, the localization of inhibin and steroidogenic enzymes (3β‐hydroxysteroid dehydrogenase/isomerase and aromatase) in the ovaries of common tree shrew (Tupaia glis) and northern smooth‐tailed tree shrew (Dendrogale murina) was immunohistochemically analysed. As in the results reported for other mammals, inhibin α‐chain was localized in the follicular epithelium of secondary or Graafian follicles in the two species. The localization of aromatase in the ovary of these two species, however, was different. In the common tree shrew, the aromatase was localized in the thecal cells, whilst in other mammals it is localized in the granulosa cells. These results indicate that in the ovary of the common tree shrew, the oestradiol may be synthesized in the thecal cells.
Immunohistochemical Demonstration of Cytochrome Oxidase in Different Parts of the Central Nervous System: a Comparative Experimental Study
Authors: Taskinalp O. , Aktas R. G. , Cigali B. , Kutlu A. K.
Published: March 2003

Cytochrome oxidase, the terminal enzyme of the electron transport chain, is a marker of the functional activity of the cell. In this study; localization of cytochrome oxidase in cerebrum, cerebellum, hippocampus, substantia nigra and choroid plexus of adult rats was investigated using immunohistochemical methods. Neural bodies were immunoreactive while neuroglial cells and axonal areas did not show significant immunostaining. The cerebral cortical substantia grisea region was stained almost homogeneously with cytochrome oxidase. In the cerebellar cortex, immunolabelling was more intense in the granular layer than the molecular layer. There was significant immunostaining in Purkinje cells. White matter, both in cerebrum and cerebellum, did not show immunoreactivity for cytochrome oxidase. Neurones in the hippocampus showed variable immunostaining; some of them were negative while others revealed high immunoreactivity. The neurones in substantia nigra were heavily labelled. Immunostaining for cytochrome oxidase in plexus choroideus epithelial cells was also remarkable. The morphological findings demonstrate the regions which most require and produce energy and reflect the differences in cellular activity in these parts of the central nervous system.
Weismanns potentiell unsterbliche Einzeller sind sterbliche Selbstklonlinge
Authors: Preuss F.
Published: March 2003

Weismann's immortal cells are mortal self‐cloning cells

The theory of Weismann (A. F. L. Weismann, 1834–1914) is reviewed in the light of recent genetic experiments and considerations.
Immunohistochemical Detection of Components of the Insulin‐Like Growth Factor System during Skeletal Muscle Growth in the Pig
Authors: Götz W. , Dittjen O. , Wicke M. , Biereder S. , Krüger U. , Von Lengerken G.
Published: March 2003

The insulin‐like growth factor (IGF) system plays an important role in postnatal somatic and skeletal muscle growth in pigs. There is little information on the occurrence and distribution of components of the IGF system in postnatal porcine skeletal muscle. IGF‐I, IGF receptor 1 (IGF1R) and the IGF‐binding proteins IGFBP‐1 and ‐3 in longissimus dorsi and triceps brachii were localized in muscle biopsies from 12 commercially crossbred pigs aged from 28 to 199 days as well as from the sire generation, by immunohistochemistry. Plasma IGF‐I concentrations were also determined using radioimmunoassays. Unlike other species, IGF‐I was localized in porcine skeletal muscle fibres. Staining intensity correlated with the highest plasma IGF‐I levels and phases of intensive muscle growth from the 11th to 22nd week. The pattern of IGF1R immunostaining, which was strong, correlated with that of IGF‐I. IGF1R was also localized in endomysial tissues. IGFBP‐1 was not detected within muscle fibres, but was found in the endomysium and vessel walls, while IGFBP‐3 was localized with IGF‐1 and its receptor. Higher magnification revealed that IGF1R, IGFBP‐3 and probably IGF‐I appeared in the tubular system. Inhibitory as well as stimulating controls of IGFBP‐1 and ‐3 on IGF functions are discussed, which may maintain a balance between autocrine growth promoting activities of IGF‐I and IGF1R.
On the Development of the Papillary Body in the Feline Claw
Authors: Bragulla H. , Ernsberger S. , Budras K.‐D.
Published: March 2003

The pre‐ and post‐natal development of the feline claw was studied in 22 feline fetuses with a crown–rump length (CRL) ranging from 40 to 160 mm, in six kittens up to an age of 22 days, and in four adult cats. In fetuses up to a CRL of 75 mm, the characteristic shape of the feline claw was developed. Segment‐specific dermal modifications in the various segments, especially the dorsal ridge, started to develop in fetuses with a CRL between 75 and 105 mm. Modifications of the papillary body in the different claw segments took place in the last third of prenatal development and were continued postnatally. At first, the basal lamina became wavy, followed by the formation of small dermal microridges, which would be enlarged to dermal ridges and lamellae. In the claw of adult cats, the papillary body was very small. The dermal tissue of the proximal part of the coronet formed low microridges with short papillae originating on and between these low ridges. In the wall segment, dermal microridges were formed which were arranged in a parallel fashion, and in the distal part of the wall, short dermal micropapillae arose on the crest of each microridge. In the sole segment, thin dermal lamellae were developed. The sequence of papillary body development and the varying conformations of the papillary body in the different segments of the feline claw are compared to those in the nail, the canine claw and hooves.
Comparative Macroanatomic Investigations of the Venous Drainage of the Heart in Akkaraman Sheep and Angora Goats
Authors: Besoluk K. , Tipirdamaz S.
Published: March 2003

This study was carried out to evaluate the origin, course and terminations of the cardiac veins in Akkaraman sheep and Angora goats. These vessels are the great cardiac, left marginal, middle cardiac, right cardiac and smallest cardiac veins. For this purpose, latex was injected into the jugular vein of eight adult healthy Akkaraman sheep and Angora goats. These veins were dissected. It has been shown that the middle cardiac vein and great cardiac veins coursed with the branches of the coronary arteries and that they were anastomosed with each other. The venous blood from the great cardiac vein and middle cardiac veins emptied into the right atria via the coronary sinus. The venous blood from the interventricular septum was conveyed to the middle cardiac vein and great cardiac veins.
Neurotrophin Receptor‐like Proteins in the Bovine (Bos taurus) Lymphoid Organs, with Special Reference to Thymus and Spleen
Authors: Levanti M. B. , Germanà A. , Catania S. , Germanà G. P. , Gauna‐Añasco L. , Vega J. A. , Ciriaco E.
Published: March 2003

Increasing evidence suggests that neurotrophins could regulate immune functions acting directly or indirectly on immunocompetent cells. The indirect pathway involves stromal cells of the primary and secondary lymphoid organs. In the present study the occurrence of Trk proteins (TrkA, TrkB and TrkC), regarded as the high‐affinity signal‐transducing receptors for neurotrophins, was investigated in cow lymphoid organs using immunohistochemistry. The thymus and spleen of both fetal and adult animals, and the palatine tonsils, lymph nodes and Peyer’s patches of adult animals, were analysed. Unidentified cells displaying TrkA‐like immunoreactivity were found in the fetal thymus, whereas those expressing this protein in the adult gland were identified as epithelial cells. In the spleen, immunoreactive TrkA was observed in cells of the white pulp. TrkB immunoreactivity in both fetal and adult thymus and spleen was localized in monocyte/macrophage cells. As a rule, TrkC was absent from the thymus and the spleen independent of the animal’s age. Different types of stromal cells, but never the lymphocytes themselves, displayed TrkA, TrkB, or TrkC immunoreactivity in the other lymphoid organs analysed. As in other vertebrate species, Trk proteins in the lymphoid organs of the cow were localized in the stromal, non‐lymphoid cells, thus suggesting that neurotrophins might regulate the immune function acting indirectly on lymphocytes.
Ultrastructure of the Spermatozoa from a Florida Manatee (Trichechus manatus latirostris)
Authors: Miller D. L. , Dougherty M. M. , Decker S. J. , Bossart G. D.
Published: March 2003

Semen was opportunistically collected from a free‐ranging, 10‐year‐old, 275 cm (total length) Florida manatee (Trichechus manatus latirostris) during rehabilitation treatments. Ultrastructure of the spermatozoa was examined by scanning and transmission electron microscopy and differed slightly from that described for other mammals. Comparisons to the manatee’s closest phylogenetic relatives, the elephant and hyrax, were made. The manatee spermatozoa had a similar acrosome but a distinct annulus and lacked the dense bodies observed in the neck of the elephant spermatozoa. Additionally, manatee spermatozoa lacked the lateral vacuoles observed in the nuclear chromatin from of the hyrax spermatozoa. These data add to our understanding of manatees and allow for comparative studies with other species that may be useful in phylogenetic and reproductive studies.
Ultrastructural Features in the Epididymis of the Dog (Canis familiaris, L.)
Authors: Chimming Bruno Cesar , Alberta Vicentini Carlos
Published: March 2003

The ultrastructure of the epididymal duct of the dog is described in this paper. The epididymis was divided into three morphofunctional segments: initial, middle and terminal. The cellular population of the lining epithelium is formed from principal, apical, basal and clear cells. The peritubular stroma and the tubular interstitium surrounding the epithelium are also described. The outcome is compared to the description made in other species of mammals.
Lipolysis and Ultrastructural Changes of Intracellular Lipid Vesicles after Cooling of Bovine and Porcine GV‐oocytes
Authors: Isachenko V. , Isachenko E. , Michelmann H. W. , Alabart J. L. , Vazquez I. , Bezugly N. , Nawroth F.
Published: March 2003

The aim of our investigation was to compare the ultrastructure of lipid droplets, and the effect of cooling on intracellular lipid vesicles of bovine and porcine GV oocytes. The lipid droplets in bovine GV oocytes have a homogeneous structure. The utilization of lipids takes place directly from these vesicles without formation of interim lipid compounds. In contrast, there are two kinds of lipid droplets in porcine GV oocytes: ‘dark’, homogeneous vesicles next to ‘grey’ vesicles with electron‐lucent streaks. Vesicles of each specific group are connected to each other. After a 12‐h culture, the formation of the cisternal smooth endoplasmic reticulum layer was always associated with ‘grey’ lipid vesicles. This is evidence that during oogenesis lipolysis takes place only in ‘grey’ vesicles. It is supposed that cytoplasmic lipolysis has two stages: ‘dark’ vesicles change into a ‘grey’ form followed by a utilization of these ‘grey’ lipids. Furthermore, both types of lipid droplets in porcine oocytes changed morphologically during cooling: they changed into a spherical form with lucent streaks. Lipid droplets in bovine GV oocytes revealed no visible morphological changes after cooling.
Ultrastructural Changes in Calvarial Osteoblast Cytoskeleton after Prostaglandin E2 Administration in Rats
Authors: Yamakura K. , Watanabe H. , Abe S. , Yanagisawa T.
Published: March 2003

Recent studies on the cytoskeleton of osteoblasts have been made mainly using cultured cells. However, the morphology of cultured cells may be altered during subculture. Therefore, cytoskeletal changes of calvarial osteoblasts were investigated in situ by electron microscopy using the detergent perfusion method to preserve cell morphology as well as selectively observing the cytoskeleton in the presence of a high concentration of prostaglandin E2 (PGE2) in the calvarial periphery in rats. Rats were perfused with a mixture of Triton X‐100 and glutaraldehyde, then the cytoskeleton was observed by transmission electron microscopy. In osteoblasts of the control group, thick bundles of microfilaments ran parallel to the long axis of the cells immediately below the cell membrane adjacent to the osteoid layer. In contrast, in the osteoblasts of the PGE2‐administered group, the external morphology was changed to an asteroid or cubic shape, and thick bundles of microfilaments immediately below the cell membrane adjacent to the osteoid were not observed, although microfilament fibres, with a diameter of 5–6 nm, were observed in the cytoplasm.
The Structure of the Masseter Muscle in the Giraffe (Giraffa camelopardalis)
Authors: Sasaki M. , Endo H. , Kogiku H. , Kitamura N. , Yamada J. , Yamamoto M. , Arishima K. , Hayashi Y.
Published: March 2003

In the giraffe (Giraffa camelopardalis), the masseter muscle was divided into several layers. The superficial and more medial (second) tendinous sheets of the masseter muscle fused with each other at the dorso‐caudal part and a fleshy portion was located between these tendinous sheets. In the rostral part, the most superficial tendinous sheet turned around as a compact tendon and attached to the facial crest (Crista facialis). The turned tendinous sheet, however, never fused with the second tendinous sheet and this layer of the masseter muscle, that originated from the facial crest with the turned sheet, was inserted into the mandible with its fleshy portion. In the cattle, goat, sheep and Sika deer, the rostral layer of the masseter muscle arises from the facial crest with its fleshy portion and is inserted into the tubercle on the mandible through the strong tendinous sheet. In this study, the takin also showed the same structure of the masseter muscle. In the giraffe, however, the rostral layer inserted into the mandible through the strong tendinous sheet could not be distinguished, thus, there was no conspicuous tubercle on the mandible. Moreover in the masseteric region of the skull, the giraffe was similar to the Sika deer in several ways. However, it is suggested that the giraffe exerts smaller forces on the cheek teeth than does the Sika deer because of its longer Margo interalveolaris.
Structural and Ultrastructural Characteristics of Interrenal Gland and Chromaffin Cell of Matrinxã, Brycon cephalus Gunther 1869 (Teleostei‐Characidae)
Authors: Rocha R. M. , Leme‐Dos Santos H. S. , Vicentini C. A. , Da Cruz C.
Published: March 2003

This work presents the structure and ultrastructure of the interrenal gland and chromaffin cells, as well as the morphology of the head kidney of Brycon cephalus. The head kidney is composed of fused bilateral lobes located anterior to the swim bladder and ventrolateral to the spinal column. The parenchyma revealed lympho‐haematopoietic tissue, melano‐macrophage centres, interrenal gland and chromaffin cells. The interrenal gland consisted of cords or strands of cells grouped around the posterior cardinal vein and their branches. Chromaffin cells are found in small groups, closely associated with the interrenal gland and/or under the endothelium of the posterior cardinal vein. So far, the ultrastructural analysis has revealed only one interrenal cell type which contained abundant smooth endoplasmic reticulum and numerous mitochondria with tubulo‐vesicular cristae, characteristic of steroid‐producing cells. Two types of chromaffin cells were observed. The first type was characterized by the presence of vesicles with round, strongly electron‐dense granules, which were eccentrically located. Such cells were interpreted as noradrenaline cells. Meanwhile, cells which contained smaller vesicles and electron‐lucent granules, with a small halo separating the granule from the vesicular limiting membrane, were identified as adrenaline cells.
Adrenergic and Cholinergic Innervation of the Mammary Gland in the Pig
Authors: FRANKE‐RADOWIECKA A. , WASOWICZ K.
Published: March 2003

Adrenergic and acetylcholinesterase‐positive (AChE‐positive) innervation of the mammary gland in the sexually immature and mature pigs was studied using histochemical methods. Upon examining the adrenergic and cholinergic innervation, the adrenergic innervation was found to be much more developed. The majority of both sub‐populations of the nerve fibres studied was localized in the subcutaneous tissue of the mammary gland. Adrenergic and AChE‐positive nerve fibres also supplied structures of the nipple (subcutaneous tissue, blood vessels, smooth muscles fibres) and glandular tissue (blood vessels, lactiferous ducts). The glandular tissue contained the smallest number of adrenergic and AChE‐positive nerve fibres. No distinct differences were observed in the adrenergic and AChE‐positive innervation of the porcine mammary gland between the juvenile and non‐pregnant adult animals.
Zur Entstehung und Funktion der Kunde, Infundibulum dentis, an den Schneidezähnen der Pferde
Authors: VOLLMERHAUS B. , ROOS H. , KNOSPE C.
Published: March 2003

On the origin and function of the enamel cup (Infundibulum dentis) on the incisors of horses

The enamel cups of equids originated phylogenetically through several phases in Oligocene and Miocene horses, which readjusted from hard to soft leaf food and from double nutrition (leaves and grass) to a pure grass intake. This has been proved experimentally. The resulting construction of the incisor is continually changed on its occlusal surface by erosion according to the pattern of the enamel crests. Referring to the whole incisor tooth, this results in an equid life cycle in which the good grip of the occlusal surface and the efficiency of ingestion favours the young, sexually mature horses, which are at the best age for food intake.
A Morphometric Study of the Structural Characteristics of the Aorta in Pigs Using an Image Analysis Method
Authors: SOKOLIS D. P. , BOUDOULAS H. , KAVANTZAS N. G. , KOSTOMITSOPOULOS N. , AGAPITOS E. V. , KARAYANNACOS P. E.
Published: March 2003

The objective of this study was to evaluate multiple structural characteristics, in addition to vasa vasorum density, in different aortic regions. The aorta of healthy Landrace pigs was divided into four thoracic and three abdominal segments. Transverse sections were reserved for morphometric analysis. Image analysis showed the aortic diameter, the thickness of the media, the number of elastic lamellae and the thickness of elastic membranes being reduced with increased distance from the heart (P < 0.05). The average thickness of lamellar units remained constant in the thoracic, but increased in the abdominal aorta (P < 0.05). The number of lamellar units, contained in the avascular zone of the media, and the density of vasa vasorum decreased peripherally (P < 0.05), still the average thickness of the avascular zone was invariant. In conclusion, the anatomical properties of the vessel wall alter through the aorta, being optimal for the varying stresses to which the aorta is subjected along its length. The distinct aortic parts may exhibit inherent morphological features, responsible for the various pathological processes that affect the aorta.
Labelling of Rat Endothelial Cells with Antibodies to vWF, RECA‐1, PECAM‐1, ICAM‐1, OX‐43 and ZO‐1
Authors: ÜLGER H. , KARABULUT A. K. , PRATTEN M. K.
Published: March 2003

Labelling with endothelium specific monoclonal antibodies, von Willebrand Factor (vWF), rat endothelial cell antigen‐1 (RECA‐1), platelet‐endothelial cell adhesion molecule‐1 (PECAM‐1), intercellular adhesion molecule‐1 (ICAM‐1), OX‐43 and zonula occludentes‐1 (ZO‐1), was investigated in cryostat sections of vessels from rats of different ages using a confocal microscope. The results showed that labelling of the vWF was positive in endothelial cells from adult, fetal and different ages of embryonic rat. Labelling with RECA‐1 was weakly positive in adult rat aorta and lung endothelial cells but not in embryonic yolk sac endothelial cells. Labelling using PECAM‐1, ICAM‐1 and OX‐43 was negative in both adult and embryonic endothelial cells. ZO‐1 showed positive but very weak reactivity in embryonic yolk sac endothelial cells. The expression of vWF on vessels from adult and 19.5‐day fetal tissues was strongly positive. However, the expression of vWF in embryonic endothelial cells was dependent on the gestational age. While the 11.5‐day yolk sac vessels stained weakly, staining gradually increased in 13.5‐, 15.5‐ and 17.5‐day‐old yolk sac vessels. The results suggest that vWF is a reliable endothelial cell marker in rat vascular endothelial cells, including both fetal and embryonic stages.
Distribution of β‐Endorphin and Substance P in the Shoulder Joint of the Dog Before and After a Low Impact Exercise Programme
Authors: KARAHAN S. , KINCAID S. A. , BAIRD A. N. , KAMMERMANN J. R.
Published: March 2003

β‐endorphin and substance P were immunolocalized in the articular cartilage, synovial membrane and fibrous joint capsule of dogs. Twelve adult greyhounds were randomly assigned to one of three groups: control, limited exercise, or regimented exercise. On day 0, biopsies of articular cartilage and joint capsule were obtained from the left shoulder joints of dogs receiving limited and regimented exercise. On day 72, biopsies of joint capsule from right and left shoulders and articular cartilage from the right shoulder joint were analysed for the presence of glycosaminoglycans (GAG) and for immunolocalization of substance P and β‐endorphin. Regimented exercise increased the presence of GAGs and immunolocalization of substance P and β‐endorphin in articular cartilage and synovial membrane compared to day 0 biopsies and untreated controls. Localization of β‐endorphin became prominent in and around the chondrocytes. Substance P was increased in chondrocytes and extracellular matrix. Concomitant changes in localization of β‐endorphin and substance P may have a role in the modulation of the microphysiological environment, metabolism, or function of joint tissues in response to low‐impact exercise.
The Influence of Stomach Volume on the Liver Topography in Cats
Authors: EKEN E. , GEZICI M.
Published: March 2003

The aim of this study has been to describe the effect of varying degrees of fullness of the stomach on liver topography in cats by means of the sectional anatomy of the abdominal cavity. Twenty‐four adult healthy cats of both sexes and of different ages were used. The cats were divided into two groups. The first group had empty stomachs and the second group had filled stomachs. Eight cats were dissected. The remaining cats were frozen at – 20 °C, eight of these were then sectioned paramedially and the other eight were sectioned transversely. In the dissection and sections, it was observed that the liver shifted considerably to the right and craniodorsally in cats with full stomachs. In this article, the topographical anatomy of the liver according to varying stomach volumes is described in a manner that is useful to veterinary surgeons and clinicians. The sectional findings obtained from the paramedial and transverse sections provide information for computed tomography and magnetic resonance imaging.
The Muscles of Mastication in the Caspian Seal (Phoca caspica)
Authors: Endo H. , Sakata S. , Arai T. , Miyazaki N.
Published: March 2003

The muscles of mastication and their related skull characters in the Caspian seal (Phoca caspica) were anatomically examined and compared with those of the Baikal (Phoca sibirica) and ringed (Phoca hispida) seals. A well‐developed masseter muscle was observed in the Caspian seal, whereas the temporal muscle consisted of thin bundles. The skull of the Caspian seal possessed the same thin frontal bone and the dorso‐ventrally developed zygomatic arch found in the Baikal seal that are required to install the enlarged eyeball into the orbit. The temporal bone was not robust, and the digastric muscle was well‐developed in the ventral space of the auditory bulla. The present results suggest that the skull form of the Caspian seal has changed morphologically from its ringed seal‐like ancestors, and suggest that the evolutionary strategy of the muscles of mastication in the Caspian seal is principally consistent with that of the Baikal seal.
Anatomical Study of the Diaphragm of the Opossum (Didelphis albiventris)
Authors: Cassel F. D. , Soares J. C. , Torrejais M. M. , Matheus* S. M. M.
Published: March 2003

The anatomical characteristics of the South American opossum diaphragm were described. Five male and seven female adult opossums, weighing between 700 and 1110 g, were used. Animals were killed by ether inhalation saturation. The abdominal and thoracic walls were dissected and opened, the viscerae were removed and the diaphragm anatomy was described and photographed in situ. After diaphragm removal, some dimensional data were taken and tabled. Primary branches of the phrenic nerves were dissected under a surgical microscope. The secondary branches were studied and described by transillumination after clarification in acetic acid. The opossum diaphragm is domed and has a mean area of 54.33 ± 3.8 cm2. Well‐identified costal, sternal and lumbar parts form the peripheral muscular region. The central tendinous region presents with a V‐like form. Three folioles comprise the phrenic centre and present different dimensions. The caudal vena cava passes through its foramen between the ventral and right dorsal folioles. Both right and left phrenic nerves present one ventral branch and one dorsolateral trunk in 50.0% and 66.67% of the cases, respectively.
Morphological Investigation of Carotid Body and Its Arteries in Rabbits
Authors: Unur E.
Published: March 2003

The purpose of this study was to determine the morphology of the rabbit carotid body and its artery at the light microscopy level. The carotid body was situated between the internal and external carotid arteries after the bifurcation point of the common carotid artery. The carotid body was usually found to be a single, ovoid tissue mass but, in some cases it consisted of two or three parts. More carotid bodies were supplied by a single carotid body artery (glomic artery) which arose from the common carotid artery or the internal or external carotid arteries near the bifurcation point of the common carotid artery.In only one case were there two arteries which arose from opposite sides of the external carotid artery at its origin. There was a distinguishable sinus (glomic sinus) at the origin of the glomic artery. This artery had a thin wall with elastic laminae in the sinus area which become thinner distal to the sinus.
Pluripotent Stem Cells – Model of Embryonic Development, Tool for Gene Targeting, and Basis of Cell Therapy
Authors: Prelle KATJA , ZINK NICOLA , Wolf Eckhard
Published: March 2003

Embryonic stem (ES) cells are pluripotent cell lines with the capacity of self‐renewal and a broad differentiation plasticity. They are derived from pre‐implantation embryos and can be propagated as a homogeneous, uncommitted cell population for an almost unlimited period of time without losing their pluripotency and their stable karyotype. Murine ES cells are able to reintegrate fully into embryogenesis when returned into an early embryo, even after extensive genetic manipulation. In the resulting chimeric offspring produced by blastocyst injection or morula aggregation, ES cell descendants are represented among all cell types, including functional gametes. Therefore, mouse ES cells represent an important tool for genetic engineering, in particular via homologous recombination, to introduce gene knock‐outs and other precise genomic modifications into the mouse germ line. Because of these properties ES cell technology is of high interest for other model organisms and for livestock species like cattle and pigs. However, in spite of tremendous research activities, no proven ES cells colonizing the germ line have yet been established for vertebrate species other than the mouse (Evans and Kaufman, 1981; Martin, 1981) and chicken (Pain et al., 1996).

The in vitro differentiation capacity of ES cells provides unique opportunities for experimental analysis of gene regulation and function during cell commitment and differentiation in early embryogenesis. Recently, pluripotent stem cells were established from human embryos (Thomson et al., 1998) and early fetuses (Shamblott et al., 1998), opening new scenarios both for research in human developmental biology and for medical applications, i.e. cell replacement strategies. At about the same time, research activities focused on characteristics and differentiation potential of somatic stem cells, unravelling an unexpected plasticity of these cell types. Somatic stem cells are found in differentiated tissues and can renew themselves in addition to generating the specialized cell types of the tissue from which they originate. Additional to discoveries of somatic stem cells in tissues that were previously not thought to contain these kinds of cells, they also appear to be capable of developing into cell types of other tissues, but have a reduced differentiation potential as compared to embryo‐derived stem cells. Therefore, somatic stem cells are referred to as multipotent rather than pluripotent. This review summarizes characteristics of pluripotent stem cells in the mouse and in selected livestock species, explains their use for genetic engineering and basic research on embryonic development, and evaluates their potential for cell therapy as compared to somatic stem cells.
Morphological Studies on Meckel's Diverticulum in Geese (Anser Anser Domesticus)
Authors: Besoluk K. , Eken E. , Boydak M. , Tipirdamaz S.
Published: March 2003

This study was carried out to reveal the morphological features of Meckel's diverticulum (MD) in geese. For this purpose, a total of 36 adult healthy geese of both sexes, 50–52 weeks of age, were used. The mean weight of MD in male was found to be significantly larger than that of female. It was located a little distal to the midpoint of the small intestine in both sexes. It had a lot of lymphoid tissues, the simple columnar epithelium and a small number of crypts, and was a lack of villi, and its muscularis mucosae was very thin. Results from this study are thought to throw light on future studies on MD and proper diagnosis of pathological disorders related to it, and to contribute considerably to the present anatomical knowledge on MD in geese.
Post‐natal Development in the Linear and Tric Morphometrics of the Camelidae Skull
Authors: Al‐Sagair O. , ElMougy S. A.
Published: March 2003

The craniometric measurements in addition to the skull, cranial and facial indices undertaken in the immature and mature maleCamelus dromedariusof the Malha phenotype (black) were: the skull length (35.99 cm), maximum width of neurocranium (11.33 cm), cranial length (15.45 cm), maximum zygomatic width (14.81 cm), viscerocranial length (20.55 cm), skull index (41.13), cranial index (73.70), facial index (72.31), cranial volume (231.73 ml) and skull weight (795.70 g) were measured in the immature camels. In the mature camels, the skulls gave the following measurements: the skull length (50.53 cm), maximum width of neurocranium (15.96 cm), cranial length (21.93 cm), maximum zygomatic width (22.75 cm), viscerocranial length (28.60 cm), skull index (45.06), cranial index (72.99), facial index (79.83), cranial volume (310.80 ml) and skull weight (2598.31 g). The results of a total of 30 skulls of immature and mature Malha camel revealed that all the measurements increased with age whereas the cranial index was the only parameter for which a decreased value was recorded. The anterior basicranial angle averaged about 203°in the immature animal to increase to an insignificant value of 204°in the mature camel skull. Similarly, the posterior basicranial angle did not exhibit a significant difference between the immature and mature values, which ranged between 110 and112°,respectively.