bluuebunny/crossref_metadata_2025 huggingface dataset:
Pneumothorax nach Mediastinalemphysem
Authors: Reimann Reinhold , Jakse Robert
Published: July 2008

By rupture of the mediastinal pleura a mediastinal emphysema may lead to a pneumothorax. An experiment imitating this process is able to point out two spots where the pleura is most likely to tear: (1) An area as large as a thumb tip above the root of the left lung; there mediastinal pleura covers a space the width of which changes most in respirating. (2) The border of a fatty fold based on the pericardium and covered by mediastinal pleura; it is there that maxima of tension occur by emphysematic inflation. In general, air from the mediastinum far more often enters the left pleural cavity than the right one.
Distribution of 3H-Thymidine in the Postnatal Hypophysis of the C57BL Mouse
Authors: Wilson Doris B.
Published: July 2008

The distribution of cells labelled with 3H-thymidine was determined autoradiographically in the adenohypophysis and neurohypophysis of the C57BL mouse during postnatal phases ranging from the newborn to 24 days of age, as well as in the adult. In the newborn, labelled cells are scarce in the neurohypophysis but common in the adenohypophysis. The neurohypophysis shows a surge in labelling at 5–9 days, with a sharp decline thereafter. In the adenohypophysis, labelled nuclei are scarce in the pars tuberalis after 19 days, whereas the pars intermedia and pars distalis continue to show labelled cells. In the pars distalis, at all phases, label occurs in the marginal cells along the hypophysial cleft as well as in deeper-lying cells representing follicular cells. In the adult, foUicular cells are more commonly labelled relative to other cells of the hypophysis.
Structure and Occurrence of Perisinusoidal Stellate Cells in the Liver of Lactating Dairy Cows
Authors: Lindberg L.-A. , Gröhn Y.
Published: July 2008

The structure and occurrence of liver stellate cells were studied in healthy, mildly and severely ketotic lactating dairy cows. In addition, the stellate cells in five clinically healthy lactating cows, each sampled at five different occasions after parturition, were studied. Liver samples were obtained by percutaneous needle biopsy, immediately fixed in 3% glutaraldehyde and processed for light and electron microscopy. The volume fractions of stellate cells and hepatocytic fat were estimated. Bovine stellate cells contained one, often large lipid droplet, not surrounded by a membrane. The cells had a well-developed Golgi apparatus and rough endoplasmic reticulum. Morphological indications for collagen synthesis by the cells were found. The results also suggest that a direct exchange of material between hepatocytes and stellate cells is possible. The volume fraction of stellate cells was decreased and the fraction of hepatocytic fat increased in severely ketotic cows as compared to the other groups. A negative correlation between the volume fractions of hepatocytic fat and stellate cells was significant. Hepatocytic fat decreased significantly after parturition, but an increase in the volume fraction of stellate cells was not significant.
Sonoanatomy of the Shoulder
Authors: Balogh Brigitta , Frühwald Franz , Neuhold Andreas , Wicke Lothar , Firbas Wilhelm
Published: July 2008

With the aid of ultrasound we tried to visualize the muscles of the shoulder region, the collum scapulae, the axillary artery and vein and the brachial plexus. We were successful with exception of the vessels and the nerves. Knowledge of the anatomical landmarks is essential in ultrasound image reading.
Ultrastructural Features of Sensory Receptors in Gingiva of New-Born Rats
Authors: Bonnaure-Mallet Martine , Le Toux Guy
Published: July 2008

The ultrastructure of the sensory receptors in the gingiva is described on the basis of material taken from ten new-born rats. The defined fine structure of the receptors at day zero suggest that they can be susceptible to tension and pression changes. They also can play a role in the ante-occlusal growth of the mandibule.
Ultrastructural and Morphometric Studies of Nonsecretory Neurons of the Rat Supraoptic Nucleus
Authors: Itoh Yasunobu , Iijima Koichi , Kowada Mayayoshi
Published: July 2008

Ultrastructural and morphometric studies were made on nonsecretory and complementarily neurosecretory neurons of the rat supraoptic nucleus. 6% of perimeter of nonsecretory neuronal perikarya was covered by presynaptic endings. The value was well in agreement with that of interneurons elsewhere. The covering ratio of neurosecretory neurons was 12%. The perikarya of nonsecretory and neurosecretory neurons bear an average of 14 and 49 axon terminals, respectively. Nonsecretory neurons should be interneurons, receiving much less information than neurosecretory neurons.
Stereological Analysis of Ultrastructural Changes of Surrounding Tissues to Neuroectoderm during Chick Embryo Neurulation
Authors: de Paz P.d. , Fernandez J.G. , Chamorro C.A. , Fernandez M. , Villar J.M.
Published: July 2008

The cytometric evolution of different subcellular components in the epiblast and the mesoderm of chick embryo during neurulation has been studied with stereological methods. The coefficient of cellular form (CFc) has specific values for each type, the epiblast having a mean CFc of 0.474, while the mesoderm, which has ellipsoidal cells, has a mean CFc of 0.643. The nucleus does not show any change of its coefficient of form although its surface density increases significantly. The proportion of mitochondria, present in the cells of each embryonic layer, remains constant during the 4 stages, being higher in the mesoderm cells (epiblast 3.6%; mesoderm 4.3%). The epiblast cells show a stable vitelline reserve, though the relative proportions of lipid bodies and yolk droplets vary: the volume density of yolk droplets increases from stage 5 (3.1%) to stage 8 (7.7%), while the lipid bodies diminish from 7 to 3.6% during this period. The mesoderm cells undergo a remarkable loss of vitelline volume during the same period. The rough endoplasmic reticulum of each cellular type has a remarkable length density increase, the significance of which is discussed in relation to production of extracellular matrix.
Methods for the Study of the Human Foetal Arterial System
Authors: de A.A. Silva S.
Published: July 2008

Micro art eriography followed by enlargement of the photographs, resin cast preparation and serial sections were techniques applied to study the arterial system of the human foetal abdomen from 12 to 20 weeks ovulation age. In order to illustrate the advantages of these techniques, the blood supply of the second portion of the duodenum of the developing foetus was demonstrated for the first time. Particular attention was directed to the recognition of anatomical variations. Vascular patterns were found to be complete in the age group studied.
Thickness of Renal Glomerular Capillary Basement Membrane in the Offspring of Diabetic Rats Fed a Regular or High-Sucrose Diet
Authors: Altshuler G. , Ornoy A.
Published: July 2008

Numerous animal model studies of diabetes mellitus have been reported. Diabetes-induced vascular damage is a common cause of systemic organ damage in humans and animals. Many investigations have been made of human and animal offspring of diabetic mothers. The present report documents the sequential glomerular basement membrane (GBM) thickness in fetuses and infants of diabetic rats. The postnatal increase in GBM thickness was similar in the offspring of control and diabetic rats, and was not related to the sucrose concentration in the diet.
Change in Facial Shape in Micro-, Macro- and Normocephalics
Authors: Lavelle Christopher L.B.
Published: July 2008

In view of the dubious scientific validity of traditional cephalometric analyses, the more accurate technique of biorthogonal analysis was used in this study. Developed from D’Arcy Thompson’s transformation grids, this technique showed similar craniofacial shape changes in micro-, macro- and normocephalics between the ages of 12 and 16 years, implying the contrasts in facial form between these 3 samples predominantly reflect size rather than shape differences.
Ultrastructure of the Submandibular Gland in 2 Species of Macaques
Authors: Nagato Toshikazu , Tandler Bernard
Published: July 2008

The ultrastructure of the submandibular glands was studied in 2 species of macaques (Macaca mulatta and Macaca irus). The glands, which were identical in both species, were predominantly serous, but contained scattered mucous acini. The serous cells contained 1 of 2 morphologically distinct secretory granules of complex substructure, whereas mucous droplets were relatively simple in structure. Other parts of the macaque glands were similar to their counterparts in other primates. The close resemblance of the serous granules to each other in the 2 species studied and to 3 other macaque species previously described by others suggests that these monkeys are taxonomically closely related.
Do B Cells and Peri-Insular Acinar Cells of Canine Pancreas Have Nerves in Common?
Authors: Radke R. , Stach W.
Published: July 2008

Synapses providing simultaneous contact with insulin-producing B cells and acinar cells have been found at the margins of islets of Langerhans in the dog. Blood vessels have also been observed in the vicinity of such synapses. The frequently described correlation between insulin and protein secretion might be a result of the simultaneous influence of these nerve endings on both enzyme- and hormone-producing cells.
Postnatal Development of Lectin-Binding Pattern in the Rat Testis and Epididymis
Authors: Arya Manjula , Vanha-Perttula Tapani
Published: July 2008

Seven rhodamine-conjugated lectins were utilized to study the distribution of glycoproteins in the developing rat testis and epididymis. In the testis a clear developmental pattern was found in Ley dig cells and the cell boundaries between Sertoli and spermatogenic cells, as well as during acrosome formation. Some of the first degenerating meiotic cells and the apical extensions of the Sertoli cells at the time of spermiation also displayed a characteristic lectin binding. The epididymal differentiation was characterized by an increasing lectin binding of the subapical Golgi zone and apical surface, and intratubular secretion prior to the arrival of sperm. After the accumulation of tubular secretion and sperm some epithelial cells were transformed into narrow (initial segment) and light cells (distal caput, cauda) with a strong affinity for some lectins. These cells appeared to be responsible for the absorption and digestion of tubular material derived from the testis and of surplus secretion and/or sperm structures.
Morphology and Morphometry of the Rabbit Uterus during Pseudopregnancy
Authors: Arnold R. , Shorey C.D.
Published: July 2008

Morphometry was carried out on the luminal epithelium of the rabbit uterus from oestrus to day 21 of pseudopregnancy. This indicated that syncytia increased in size until day 18, after which a rapid reduction occurred with approximate oestrous dimensions being restored on day 21. Involution of syncytia took place in two overlapping stages with reduction in nuclear numbers occurring from day 12 onwards, followed by loss of cytoplasm mainly after day 18. Ciliated cells predominated at oestrus and day 21 but were sparse at other times. When ciliated cells were plentiful, they were concentated on the tops of the mucosal folds.
Developmental Changes in the Inner Surface Structure of the Bovine Large Intestine
Authors: Asari Masao , Kashiwazaki Naomi , Kawaguchi Naohiko , Fukaya Kosaku , Kano Yutaka
Published: July 2008

The developmental pattern of the bovine fetal large intestine was studied with particular reference to the appearance and decline of the intestinal villi during the fetal period. In the bovine large intestine, the first rudimentary villus and goblet cells were seen in the rectum in a fetus estimated to be 3 months old. By 5–6 months, the goblet cells, absorptive cells in the intestinal crypts, and vacuolated cells in the villi were present along all segments of the large intestine. By 8–9 months, the villi have disappeared from the colon and rectum, epithelial cells no longer contain vacuoles, and absorptive and goblet cell populations are emerging from the crypts. These histological results suggest that development in the bovine large intestine follows a rectocecal gradient and the most distinct turning point during the fetal period is the first disappearance of fetal villi in the rectum of fetuses estimated to be 7 months old. After this stage, the mucous membrane of the colon and rectum matured rapidly before birth. In contrast, the cecum may seem to require further development in perinatal life.
Nature of Macrophages in Rat Brain
Authors: Boya J. , Calvo J. , Carbonell A.L. , Garcia-Mauriño E.
Published: July 2008

The nature of phagocytes appearing in lesions of the central nervous system is strongly debated with a tendency to assess an exclusively hematogenous origin. We studied the origin of phagocytes appearing in a stab wound in the rat brain. Histochemical stains for acid phosphatase and peroxidase, and silver impregnation techniques were used for our study. The results obtained showed the existence of two macrophage types: endogenous microghocytes and exogenous monocytes.
Early Dentinogenesis in Mice: von Korff Fibres and Their Possible Significance
Authors: Wigglesworth Donald J. , Longmore George A. , Kuc Iris M. , Murdoch Colleen
Published: July 2008

By light and electron microscopy we have confirmed the collagenous nature of von Korff fibres in early dentinogenesis in mice. Each fibre array begins as an argyrophil ‘stem’ lying between the outermost cells of the dental papilla, with finer divisions passing into the papilla. With the appearance of odontoblasts, a cone-like ‘spray’ of non-argyrophil fibres in continuity with the stem spreads peripherally between these cells to the dental epithelial basement membrane. After the sprays become immured in dentine matrix, the stems are removed. Later, new stems appear. Sprays are restricted to enamel-bearing parts of teeth. The possible nature and functions of von Korff fibres are discussed.
Sex Dimorphism in the Thyroid Gland
Authors: Malendowicz Ludwik K. , Bednarek Janusz
Published: July 2008

This study was designed to explain whether the sex-dependent differences in the structure of the thyroid gland of adult male and female rats depend on quantitative or qualitative changes in the thyroid follicular cells. Absolute thyroid gland weight was similar in male and female rats, but its relative weight was markedly higher in females however. Volume fractions of epithelium and stroma were higher and that of colloid lower in male than in female rats and the epithelium/colloid ratio was higher in the males. Also absolute the volumes (in mm3) of epithelium and stroma were higher in the males; the thyroid gland of females contained more colloid. The average volume of a thyroid follicular cell, estimated by stereology, was higher in males than in females, although the thyroid gland contained similar numbers of follicular cells in both sexes. Also, thyroid glands from both male and female rats contained a similar DNA quantity. Results of the present study show that the sex dimorphism in the rat thyroid depends upon a difference in the mean volume of thyroid follicular cells, with males having larger cells than females. However, in both sexes the thyroid gland contains a similar quantity of these cells.
Choriocapillaris Atrophy after Experimental Destruction of the Retinal Pigment Epithelium in the Rat
Authors: Korte Gary E. , Gerszberg Teddy , Pua Florence , Henkind Paul
Published: July 2008

Rats that receive intravenous injections of sodium iodate develop a retinopathy characterized by the partial loss of the retinal pigment epithelium (RPE). In thin sections examined by transmission electron microscopy the choriocapillaris atrophied adjacent to areas of RPE destruction. The endothelial cells thickened and lost their fenestrae and the lumen of the capillary was reduced. At sites where the RPE remained normal in appearance the choriocapillaris did not atrophy. Scanning electron microscopy of vascular casts of the choriocapillaris showed the coexistence of atrophic and normal choriocapillaris throughout the retina, presumably adjacent to sites where the RPE was destroyed or spared, respectively. Our observations support the concept that the RPE exerts some control over the structure and function of the choriocapillaris.
Change of Some Quantitative Indices of the Proximal and the Distal Growth Cartilage of the Human Tibia during the Period of the Prenatal Osteogenesis
Authors: Baltadjiev G.
Published: July 2008

The zones of the tibial growth cartilage of human fetuses (6th lunar month), premature newborns (7th–8th lunar month) and mature newborns were micrometrically studied. The zone thickness, the chondrocyte number in a certain area and in the cell columns as well, and the volume density of the chondrocytes were determined. The obtained quantitative data show that the three indices undergo certain changes during the three age periods of the prenatal osteogenesis studied. They differ in the proximal and in the distal cartilages as well. The fetal tibia is found to be growing more intensively at its distal end. The quantitative processes within the growth cartilages of the tibia are more active during the earlier stages of the intrauterine period while the qualitative processes are found to be more active at the end of the intrauterine period.
Quantitative Method for the Classification of Human Mandibular Condyles
Authors: Anagnostopoulou Sophia , Venieratos Dionyssis
Published: July 2008

This study is concerned with the classification of mandibular condyles on the basis of the shape of their frontal section. In a previous work, Yale et al. [Oral Surg. 16: 572–577,1963] had divided mandibular condyles into 4 groups: flat, convex, angled, and round. The distinction between them had been found upon simple inspection. In this paper a quantitative method is proposed, in which mandibular condyles may be classified into the same 4 groups according to inequalities concerning measurable parameters of their frontal section. The process is greatly facilitated by the use of a programmable computer. The proposed method has been applied to a sample of 254 human mandibles (hence 508 condyles); the percentage of each group has been the following; flat 11%; convex 38%; angled 41%, and round 10%. It is plausible to surmise that the quantitative character of the proposed method may be of signifficant use in oral radiology as well as in anthropological research.
Some Observations on the Posterior and Lateral Bridge of the Atlas
Authors: Taitz Cecil , Nathan Hilel
Published: July 2008

Six hundred and seventy-two atlas vertebrae of 6 population groups were examined for the presence of a posterior and/or lateral bridge. Of these, 174 (25.9%) presented with partial posterior bridge formation and 53 (7.9%) with a complete bridge. Twenty-six (3.8%) showed some form of lateral bridging. Although controversy exists as to the origin of atlas bridging, the findings of the present study show that aging could be a factor predisposing to complete bridge formation. The clinical significance of bridge formation is discussed with reference to their possible effect on normal vertebral artery function, particularly in rotation.
Microcolonies of Hemopoietic Cells in the Rat Choroid Plexus during the Neonatal Period
Authors: Lafarga M. , Berciano M.T.
Published: July 2008

Microcolonies of hemopoietic cells have occasionally been found in the choroidal stroma of the rat myelencephahc choroid plexus during neonatal life. These hemopoietic foci are mixed colonies mainly composed of erythroblasts and maturing megakaryocytes; graunulocyte precursors were not identified. The morphological data indicate that both erythro- and magakaryopoiesis occur in these microcolonies. With respect to their origin, we suggest that circulating pluripotential stem cells may colonize the choroidal stroma and produce erythro- and megakaryocyte cell lines.
Arrangement of the Sclerocorneal Trabecular System in Human Fetuses
Authors: Ruano-Gil D. , Costa-Vila J. , Barastegui C.
Published: July 2008

By studying the eyes of 20 human fetuses 33–326 mm in length (8 to 36 weeks gestation) with the light and scanning electron microscope we show that the sclerocorneal and the uveal trabecula cannot be considered as independent structures, since embryologically and morphologically they are the sclero-corneo-iridal insertions of the longitudinal fibres of the ciliary muscle.
Incorporation of Leucine by Mouse Synovial Cells in vivo
Authors: Bjorenson Jean E. , Berg Norton B. , Olsen John A. , Austin Peter
Published: July 2008

Following 3H-leucine administration, mouse synovium was examined autoradiographically at various postinjection times to determine whether the pattern of 3H-leucine utilization in vivo is comparable to that previously reported in vitro. Synovial cells incorporated 3H-leucine in significantly greater amounts than other cells examined. The pattern suggested intracellular incorporation, followed by secretion.
Innervation of Lymph Nodes: A Combined Silver Impregnation and Electron-Microscopic Study
Authors: Novotny G.E.K. , Kliche K.O.
Published: July 2008

Using silver impregnation and electron-microscopic techniques, nerves have been demonstrated in rat axillary, cervical and inguinal lymph nodes, and their distribution was investigated. With the electron microscope, vesicle-containing varicosities or terminals are demonstrated in close proximity to reticulum cells, lymphocytes, plasmablasts and mature plasma cells. Nerves supplying the blood vessels possibly differ from those supplying stromal or lymphocytic elements.
Retinal Epithelial Fine Structure in the Grey Seal (Halichoerus grypus)
Authors: Braekevelt C.R.
Published: July 2008

The morphology of the retinal epithelium and the closely associated choriocapillaris and Bruch’s membrane (complexus basalis) has been investigated in the eye of the grey seal (Halichoerus grypus) by electron microscopy. The retinal epithelium is composed of a single layer of cuboidal cells joined laterally by apically-located junctional complexes. Basally (sclerally) these cells display numerous infoldings while apically (vitreally) abundant processes enclose rod outer segments. Internally the large vesicular nucleus is centrally located. Smooth endoplasmic reticulum, mitochondria and lysosome-like bodies are abundant. Rough endoplasmic reticulum and polysomes while present are not plentiful. Phagosomes of outer-segment discs are only occasionally noted in the light-adapted state. As the entire fundus is overlain with a choroidally located tapetum cellulosum, only at the extreme periphery is an occasional melanosome present in these epithelial cells. The choriocapillaris endothelium is highly fenestrated and the profiles of these capillaries are deeply indented into the epithelial layer. Bruch’s membrane (complexus basalis) is reduced to a trilaminate structure rather than the typical pentalaminate membrane seen in most mammalian species and when associated with capillary profiles is further reduced to a single thick basal lamina.
Dynamic Model of the Equine Hindlimb during the Swing Phase
Authors: van Gurp M. , Schamhardt H.C. , Hartman W. , Crowe A.
Published: July 2008

A dynamic model is developed to describe the swing phase of the hindlimb of a normally walking horse. The limb was represented by four rigid segments constrained to move in a sagittal plane only. The mathematical equations of motion of this four-element pendulum were formulated using Lagrange’s theorem. The morphometric parameters from the hindlimb segments of 3 horses were determined using high-speed film analysis. Five muscle groups were incorporated in the model. Muscle activity was derived from earlier EMG measurements. Optimization of muscle moments resulted in a simulated swing movement that approximated that in the living animal.
Ultrastructural Analysis of Chick Embryo Blastoderms Explanted in vitro in Absence of Endoderm
Authors: Arias M. , Garcia C. , Villar J.M.
Published: July 2008

A study of the structural characteristics of stage 5 chick embryo blastoderms, cultured in vitro, was carried out after previous elimination of endoderm to analyse the differentiation capacity of mesoderm. Our results show that only the precardiac mesoderm is determined at this early stage and that it is able to differentiate cardiac tissue in the absence of the endoderm. The ultrastructural characteristics of this tissue are described. However, the degree of differentiation of cardiomyoblasts does not reach the expected level of organization and myofibrillar complexity.
Comparative Anatomical Study of the Carotid Circulation in Gundis, with Implications for their Evolutionary History
Authors: Bugge Jørgen
Published: July 2008

The carotid circulation pattern in gundis (Ctenodactylidae) is examined and compared with that of typical members of the classical rodent suborders. On this basis their probable phylogenetic relationships and systematic position are discussed. Together with other recent investigations, the unique pattern of cephalic arterial supply emphasizes the isolated position of the ctenodactylids.
Quantitative Topochemistry of Rat Liver Enzymes during Postnatal Development in Relation to Activity-Rest Cycle
Authors: Bhattacharya Radium D. , Araki Tsutomu , Yamada Masa-oki
Published: July 2008

A quantitative histochemical method (Trident) has been adapted to measure the activities of 4 enzymes, succinate dehydrogenase (SD), isocitrate dehydrogenase (ICD), glucose-6-phosphate dehydrogenase (G6PD) and 6-phosphogluconate dehydrogenase (6-PGD), within the liver acini of the rat during the postnatal developmental period. Quantitative changes of these enzymes in livers of rats of 25 g and 50 g body weight were studied, with particular emphasis on the activity-rest cycle. The results indicate a time-dependent heterogeneous distribution of enzymes along the acinar zones and the pattern of localization is age-dependent. When the mean enzyme activity from each group in relation to the time of the day are compared, a mirror image of each other could be seen. In general, a high enzyme activity has been observed during the resting phase in 25-g rats and low in 50-g rats. During the developmental period, the mean ICD activity is diminished, whereas G6PD and 6-PGD are augmented, and SD activity remains unchanged.
A New Bony Canal on the Clival Surface of the Occipital Bone
Authors: Wo-hua Zhang , Wen-chun Yen
Published: July 2008

Three cases of a bony canal have been found in 100 adult cranial bases on the lower half of the clival surface. The possible content, nature and significance of this canal are discussed and the term ‘inferior median clival canal’ assigned to this variety.
Ultrastructure of Muscle Satellite Cells in Hypersomatotropic Rats
Authors: Campion Dennis R. , McCusker Robert H. , Richardson Richard L.
Published: July 2008

Female Wistar-Furth rats were injected at one week of age with cells from either the GH1 or GH3 rat pituitary cell lines. Controls were injected with vehicle. Rats were killed at 11 weeks of age and satellite cells in the soleus and extensor digitorum longus (EDL) muscles were examined using transmission electron microscopy. Satellite cells in both the soleus and EDL muscles of rats with tumors which secreted growth hormone generally appeared to be metabolically more active than those cells seen in the muscles of control rats. The source of pituitary cell line did not appear to influence satellite cell ultrastructure. In rare instances, myofibers of tumor-bearing rats appeared to extend cytoplasmic projections around satellite cells as if to engulf the latter. There was no evidence of a pathological condition. Since only one time frame was observed, the effects of prolonged exposure to elevated blood growth hormone levels on satellite cells are not known.
Cerebral Ventricles of the Friesian Cow (Bos taurus L.)
Authors: Lignereux Y. , Fargeas J. , Marty M.-H. , Bénard P.
Published: July 2008

Six heifers, aged 8–10 months, and 4 cows, aged 4–12 years, were used for studying the conformation of the cerebral ventricles on mouldings, and the topography on scanographs and frozen cuts. The morphologic changes with age concern the height of the 3rd ventricle, the extension of the pellucid septum and the stereotaxic topography. The stress is put on the variability of the volume of the lateral ventricles and the permanence of a vast and patent recessus olfactorius, with easy external landmarks.
Cytodifferentiation of the Interstitial Cells of Cajal of Mouse Colonic Circular Muscle Layer
Authors: Faussone- Pellegrini Maria-Simonetta
Published: July 2008

Cytodifferentiation of the interstitial cells of Cajal related to the plexus entericus extremus and located on the inner face of the circular muscle layer of the mouse colon was studied in fetuses at term, unfed neonates, suckling and weaning young animals. In fetuses at term, the interstitial cells of Cajal are not found and their precursor cells are not identifiable among the cells present in the submucosal area facing the circular muscle layer, i.e., undifferentiated cells (mainly close to nerve fibers) and fibroblast-like cells (contacting each other and the developing smooth-muscle cells). Cells putatively considered as precursors of interstitial cells of Cajal, fibroblast-like cells rich in mitochondria, are present in unfed neonates (in small numbers) and in suckling animals (in large numbers). Differentiating interstitial cells of Cajal are undoubtedly recognizable during the second week of postnatal life (suckling period). Some of them have mixed fibroblastic- and interstitial-cell features and some have many interstitial-cell features. Both these cell types are already in contact with each other and differentiating and differentiated smooth-muscle cells. The undifferentiated cells, still present in unfed neonates, envelop the nerve fibers and differentiate as Schwann cells during the suckling period. During this period, as the nerve endings of the plexus entericus extremus develop, they immediately contact the differentiating interstitial cells of Cajal. During the weaning period, these cells are quite well differentiated although they do not have the same morphology as in adult animals before 30 days of age. Concomitantly, the nerve endings of the plexus entericus extremus contain an increasing number of synaptic vesicles.
Die Arteria radialis superficialis
Authors: Sachs Michael
Published: July 2008

During the clinical investigation of 570 soldiers of the German army, we were not able to feel the pulse in 5 cases at the typical place of the radial pulse in the distal part of the forearm. In these 5 cases we were able to find a subcutaneous artery which coursed superficial to the anatomical snuffbox and crossed superficial to the tendon of the extensor pollicis longus muscle. This superficial radial artery enters the deep aspect of the palm between the first and the second metacarpale bones. In three cases we found a bilateral occurrence of this artery, the other variations were observed unilaterally, two on the right side and one on the left side of the forearm. In the family of two patients other members were found who had the same variation of the radial artery. In one of the cases an arteriography of the vessels was made to find the exact anatomical course of the observed variation. We compared our results with the literature on this variation of the radial artery and found agreement on the following course for this vessel. The radial artery divides in the distal fourth of the forearm (5–7 cm proximal to the wrist joint) into two branches. The dorsal branch courses subcutaneously over the tendon of the brachioradialis muscle and runs over the tendon of the extensor pollicis longus muscle to enter the deep aspect of the palm in the first metacarpal space. This dorsal branch courses parallel to the superficial branch of the radial nerve. The palmar branch can be regarded as the ‘normal’ radial artery, which continues along the medial border of the brachioradialis muscle and courses deep under the tendons of the dorsal muscles of the thumb. The rare appearance (frequency ∼1%) of a superficial radial artery in man has probably some phylogenetic importance. This is proven by studies on the comparative anatomy of mammals. This variation of the radial artery seems to be homologous to the superficial radial artery which is described in many lower mammals. In human embryos a superficial radial artery is found as well which courses parallel to the superficial branch of the radial nerve and ends on the dorsal side of the hand. Taking all the anatomical and embryological facts into consideration we propose to name this variation of the radial artery the ‘arteria radialis superficialis’.
Correlation between the Structural and Functional Differentiation of Chick Embryo Cardiomyocytes in Cellular Aggregates
Authors: Arias M. , Villar J.M.
Published: July 2008

In order to establish the possible relation of the structural characteristics acquired by cardiomyocytes and their functional differentiation (spontaneous contractions), a study of the myofibrillogenesis on chick embryo at Hamburger-Hamilton stage 5 was carried out using techniques of dissociation and cellular reaggregation.
Somatostatin Cells in the Gastric Mucosa of Small Ruminants
Authors: Weyrauch K.D. , Blähser S. , Perschbacher J.
Published: July 2008

The distribution of somatostatin cells was investigated immunohistochemically in the epithelium of the abomasal mucous membrane of sheep and goats. Tissue samples were taken from different areas at the lesser and greater curvature of the glandular stomach. More somatostatin cells per 0.5 mm2 were found in sheep than in goats, predominantly in the pyloric gland region. In the pyloric area of both species the mucosa in the greater curvature contained more immunoreactive cells than the one in the lesser curvature. A few somatostatin cells with basal cytoplasmic processes of the ‘open type’ were observed over the entire abomasal mucosa.
Localized Morphological Differentiation in the Bipolar Cells of the Chick Retina
Authors: Quesada A. , Ambrosíani J. , Dorado M.E. , Génis-Gálvez J.M.
Published: July 2008

On a morphological and ultrastructural level, we studied a thickening which appears on the ascending prolongation of bipolar cells in the chick retina. We first observed this thickening on day 10 of incubation and it remains unchanged throughout the postnatal life of the chick. Its presence seems to be related to the synaptic activity at a dendritic level in certain bipolar cells.
Relationship between Motoneuron Number and Myofibre Number in the Pig
Authors: Stickland N.C.
Published: July 2008

A segment (at level Tl) of spinal cord and a midbelly slice of the m. semitendinosus were removed from the largest- and smallest-birthweight littermate of each of 12 Large White pig litters sacrificed at various ages. When the ratio of myofibre numbers for large to small littermate within each litter was related to the ratio of motoneuron numbers then a significant correlation (r = 0.638, p < 0.05) was observed. It is suggested that in utero growth retardation causes a reduction in myofibre numbers (within a litter), which in turn reduces motoneuron survival rate.
Identification of Adipose Tissue Primordia in Perirenal Tissues of Pig Fetuses: Utility of Phosphatase Histochemistry
Authors: Hausman G.J.
Published: July 2008

Perirenal adipose tissue samples were obtained from fetuses removed from pregnant (crossbred) sows at 3 stages of gestation (70, 90 and 110 days). Phosphatase histochemistry, succinate dehydrogenase (SDH) histochemistry and factor VIII antigen immunocytochemistry were conducted on fresh-frozen cryostat sections. Age-associated changes in nucleosidediphosphatase (NDPase) reactions in the arteriolar system were correlated with the morphological development of the medial layer of arterioles and arteries. For instance, a strong NDPase reaction in small arterioles was associated temporally with the assumption of a normal smooth-muscle cell morphology and arrangement in the medial layer. Age-associated changes in blood vessel reactions for factor VIII antigen and alkaline phosphatase activity were not correlated with morphological development. In the youngest fetuses, alkaline phosphatase activity was evident in large and small arterioles, but in the oldest fetuses, alkaline phosphatase activity was restricted to the smallest arterioles and vessels associated with them. Arteriolar differentiation was demonstrable with either adenosine triphosphatase (ATPase) or inosine diphosphatase (IDPase) reactions. Primordial stromal cells around differentiated arterioles were reactive for ATPase but not for IDPase activities. In older fetuses, there were large areas that contained ATPase-reactive stromal cells, no adipocytes, differentiated (ATPase and IDPase) arterioles and few capillaries. Positive reactions for SDH were evident in the ATPase-reactive stromal areas that contained no adipocytes. Differentiated adipocytes were SDH- and ATPase-reactive. These data illustrate the utility of differential phosphatase histochemistry to identify adipose tissue primordia.
Ependyma of the Rat Fourth Ventricle and Central Canal: Response to Injury
Authors: Bruni J.E. , Anderson W.A.
Published: July 2008

The response of ependyma in the fourth ventricle and central canal to injury was investigated in young Sprague-Dawley rats. Animals received either a small unilateral incision in the lateral funiculus of the thoracolumbar (TL) cord or a puncture wound in the dorsolateral medulla. Control and lesioned rats were killed from 2 to 21 days after operation and the tissue encompassing the lesions was processed for light microscopy and transmission electron microscopy. Randomly selected lesioned and control rats received colchicine (0.2 mg/l00 g s.c.) 6 h prior to death at postoperative days 1–4. In controls, the central canal of the TL cord was lined by a single layer of uniformly arranged columnar ependymal cells with large basally located nuclei and apically displaced organelles. Prominent membrane fusions and condensations of filaments were consistent features of the apical region of these cells. Their basal poles abutted directly on the subjacent neuropil and occasionally gave rise to radially directed processes. In rats with TL lesions, the lumen of the central canal was collapsed and lined by an irregularly contoured, multilayered appearing ependyma. Ependymal cells were often radially elongated and possessed filament-filled basal processes. Mitotic rates among ependymal cells of lesioned rats reached a maximum of 3.34% on day 2 compared to 0.21 and 0.28% in intact and sham-operated controls, respectively. Mitotic activity declined progressively thereafter and approached control values by day 4. A similar but less pronounced pattern of proliferative activity was seen distal to the cord lesion, however, little activity was observed within the lining of the fourth ventricle of animals with comparable lesions in the medulla. Ependyma in the rat spinal cord, unlike the fourth ventricle, retains a significant regenerative capacity that can be evoked by localized experimental injury.
Correlative Light and Scanning Electron-Microscopic Study of Feline Gastric Mucosa: The Cardiac Region (Pars cardiaca)
Authors: Al-Tikriti M. , Al-Bagdadi F.K. , Henry R.W. , Hoskins J. , Titkemeyer C.
Published: July 2008

The cardiac region (pars cardiaca) of the cat’s stomach was examined with light and scanning electron microscopy. The glands are simple, coiled tubular, and contain mucus-secreting cells. Their surfaces are covered with microvilli which are concentrated on the boundaries of the mucus-secreting cells. A few cells interposed between the glandular cells are probably G cells. They are identified by apical projections of long microvilli into the lumen of the gland. The surface epithelial cells lining the cardiac region are covered by minute microvilli. The muscularis mucosae is not distinctly divided into two layers. However, a group of smooth muscle cells which are directed in a circular manner around the gastroesophageal junction is considered to be the distal esophageal sphincter.
Subcorneal Macrophages in the Development of the Anterior Chamber in the Chick
Authors: Ambrosiani J. , Quesada A. , Armengol J.A. , Génis-Gálvez J.M.
Published: July 2008

We describe the changes in the population of the macrophage cells during various phases of development of the anterior eye chamber and discuss the role these cells play in this developmental process in the chick.
Intrinsic Innervation of the Uterus in Guinea Pig and Rat
Authors: Mustafa Fatima , Fatani J.A. , El-Eishi Hamdi , El-Badawi Mohamed G.
Published: July 2008

The pattern of distribution of cholinergic and adrenergic nerves in the uterus of albino rats and guinea pigs was examined histochemically. In the albino rat, the uterus was found well-innervated by both adrenergic and cholinergic nerves with a clear regional variation. Dense innervation was demonstrated at the tubal and cervical ends of the uterus and in the cervix. Cholinergic nerves supplying the glands were more numerous than the adrenergic nerves which were relatively few. In the guinea-pigs, the uterus was richly innervated by adrenergic nerves with a clear regional variation. No cholinesterase-positive nerves or nerve cells were demonstrated.
Reproduction in the Male Llama (Lama glama), a South American Camelid
Authors: Delhon Gustavo A. , von Lawzewitsch Irene
Published: July 2008

The cycle of the seminiferous epithelium of the llama was divided into eight stages, using as criteria the shape and distribution of the germ cell nuclei, the location of the spermatids, the presence of meiotic figures and the release of spermatozoa from the tubular wall. Cell populations making up each stage are described. The relative frequencies of stages 1 through 8 were: 9.86, 12.46, 17.65, 14.12, 5.81, 8.09, 13.04 and 18.89%, respectively. In the seminiferous epithelium, spermatogonia of the A and B type are present and twelve spermiogenic steps can be recognized. Interstitial (Leydig) cells are packaged together forming large masses and elongated cords and share the intertubular space with one or two central great lymphatic vessels and few capillaries. Season male Leydig cells contain lipid droplets in their cytoplasm and show a marked immunoreactive testosterone reaction.
Topographic Organization of the Karyometric Response to Neonatal Castration of the Male Mouse in the Paraventricular and Ventromedial Hypothalamic Nuclei
Authors: Pérez-Delgado Mariade del Mar , Serrano-Aguilar Pedro Guillerm , Castañeyra-Perdomo Agustin , Ferres-Torres Romualdo , González-Hernández Tomas
Published: July 2008

We have analysed the karyometric development of four topographic subdivisions of the paraventricular nucleus (rostral, medial, lateral and caudal) and three topographic subdivisions of the ventromedial nucleus (ventral, central and dorsal) of the hypothalamus in neonatally castrated male mice. Castration at birth produces a decrease of the nuclear sizes from the 10th to the 35 th postnatal day, but after this age, no differences were detected in comparison with the sizes of the control male mice. Neonatal gonadal hormone deprivation also produces changes in the nuclear shape of the nuclei, that tend to be more spherical in both centres, as we could establish after the study of the form factor parameter (perimeter/area ratio). We have found differences in the response of both hypothalamic nuclei to neonatal castration and differences in the response of the topographic subdivisions of both of them.
The Variability of the Circulus arteriosus (Willisii): Order or Anarchy?
Authors: Hillen B.
Published: July 2008

The variation of the circulus arteriosus is studied using multivariate methods. The data which form the basis of this study are 19 measurements of half the circumference of the arteries that form the circle of Willis and its afferent and efferent branches; 100 circles of Willis were measured for this purpose. Since the number of variables per individual is large, multivariate statistical techniques are the most appropriate method to gain insight in the relations of vessel sizes that exist within the circle of Willis. So a principal component analysis was performed on the data. The results clearly show a number of relations between vessel sizes. In general, inverse relationships were found of vessels that have (at least partially) an identical irrigation area: both internal carotid arteries and the ipsilateral posterior communicating artery show an intimate relationship and are together inversely related to the basilar artery and the precommunicating part of the posterior cerebral artery. Inverse relationships are also found for both vertebral arteries and both precommunicating parts of the anterior cerebral arteries. The homonymous efferent arteries appear to be closely related and show an independent variation. Together the first six principal components explain 69% of the variance. These results support a haemodynamical hypothesis on the explanation of the variability of the circle of Willis. Moreover, the differential growth in the head-neck region during the first two decades of life is postulated to be the origin of a part of the variation.
Morphologische Untersuchungen am Peri- und Epineurium aus dem Kompressionsbereich des Nervus medianus bei Karpaltunnelsyndrom
Authors: Kühnel W. , Schramm U. , Lösch G.M. , Schrader M.
Published: July 2008

The structure of the peri- and epineurium of the median nerve in the carpal tunnel syndrome was studied by light and transmission electron microscopy. Electron microscopy confirms the flattened lamellar arrangement of the perineurial cells, but in contrast to the normal architecture the perineurial component of the median nerve in carpal tunnel syndrome consists of 20–25 layers of ramified squamous-type cells, each layer being separated from the adjacent one by a wide space containing thick bundles of collagen fibrils. The perineurial cells are bounded on both sides by a basement membrane which is of substantial thickness. A prominent feature is the occurrence of multiple pinocytotic vesicles and caveolae opening on both the internal and external aspects of the flattened cells. They also contain bundles of closely aggregated filaments. In the spaces between the perineurial cells we find, in some places, extremely disorientated and individually abnormal fibrils and fine filaments arranged in form of a spider web. Matrix vesicles can also be seen. The epineurium of the median nerve in the carpal tunnel syndrome is also considerably thickened, and the attachment is solid, so that the median nerve is relatively immobile constricted like an hourglass.The thick collagen fibers are orientated predominantly parallel to the axis of the nerve, but circular fibers can also be seen. Apart from fibroblasts, the outer layer of the epineurium contains mast cells and vasa nervorum as well as myelinated nervi ner-vorum. Variable quantities of fat are also present, particularly in the surrounding loose connective tissue*.
Decreased Arterial Vasculature of the Epididymal Head in XXSxr Pseudomale (‘Sex-Reversed’) Mice
Authors: Le Barr Deborah K. , Blecher Stan R.
Published: July 2008

The microvasculature of epididymides of mature normal XYmice was found to be similar to that reported for other species. The abundant arterial supply to the initial segment is consistent with reports of extensive blood supply associated with high levels of metabolic activity in this segment. We have previously reported the absence of the initial segment in XXSxr pseudomale (‘XX sex-reversed’) mice. We now present evidence of a decreased arterial supply to the proximal region of the epididymal head in XXSxr pseudomales, including the absence of the dense peri-tubular microvascular network which surrounds the initial segment in the normal epididymis.