bluuebunny/crossref_metadata_2025 huggingface dataset:
Erythrophagocytosis by cells of the trophoblastic epithelium in the sheep placenta in different stages of gestation
Authors: Myagkaya G. , Vreeling-Sindelarova H.
Published: February 2009

Erythrophagocytosis by the trophoblastic epithelial cells of the sheep placenta was studied in different stages of gestation. Light-microscopic observations showed that the erythrophagocytosis became more and more conspicuous with increasing stages of gestation. Electron-microscopically, this process appeared to take place in the same way as described for red cell destruction elsewhere. Light-microscopically, a high acid phosphatase activity could be demonstrated in the cells which took part in the process of erythrophagocytosis. Degenerating epithelial cells were found, the number of which appeared to increase with the stage of gestation. Under the electron microscope, the cytoplasm of these degenerating cells appeared to contain a diversity of crystals, myelin-like figures and irregular coarse concretions.
A morphological study of the carotid body and the fibre content of carotid nerve in the buffalo
Authors: Prakash Prem , Rao G.S.
Published: February 2009

In the buffalo the carotid body is located in the periarterial connective tissue of the occipital artery immediately cranial to the bifurcation of the common carotid artery. The carotid body is lobulated and does not appear to contain chromaffin tissue. Nerve terminals have been seen in close relation to the glomus cells. A quantitative study of the fibre content of the carotid nerve and the carotid body has also been made. The myelinated fibres in the carotid nerve range from 278 to 473, with a mean of 386 ± 39 fibres. The histogram of myelinated fibres is distinctly unimodal. Of the myelinated fibre population, 55.4% of fibres have diameters of 2 µm, 34.1% of 4 µm, 9.5% of 6 µm and 1% have diameters of 8 µm. The mean greatest sagittal sectional area of the carotid body is 0.58 ± 0.09 mm2. The mean density (per mm2) of glomus cells is 9,216 ± 378. It appears that the organ is highly vascular (473 ± 56 blood vessels/mm2 area). The mean size of the glomus cells is 7.85 ± 0.46 µm × 10.02 ± 0.64 µm (short diameter × long diameter), whereas the mean size of their nuclei is 4.96 ± 0.19 µm × 5.52 ± 0.27 µm.
Chemo-architectonic studies in a submammalian brain
Authors: Tewari H.B. , Sethi J.S
Published: February 2009

The present report deals with the histo-enzymological mapping of adenosine triphosphatase and simple esterase in the diencephalon and mesencephalon of Uromastix hardwickii. The enzymatic make-up, in both cases, does not differ markedly in the various nuclei; few variations, of course, occur in some midbrain areas like pretectal nuclei. The latter are intensely positive for ATPase, while these nuclei are moderate to simple esterase. Nevertheless, one of the most interesting results pertaining to simple esterase activity is of a high order in the fiber tracts in comparison to ATPase. The other interesting feature relates to the fact that generally intensely positive nuclei, in ATPase preparations, are those which have extensive efferent fibres. The metabolic significance of high degree of ATPase activity vis-à-vis extensive efferent connections has been exhaustively discussed, besides the possible significance of the general data obtained.
Influence of cell density of nuclear size in monolayer cells from embryonic mouse brains
Authors: Zimmermann B. , Adhami H.
Published: February 2009

Studies were carried out on the nuclear size of embryonic mouse brain monolayer cells at various cell densities. The variation in cell density resulted from different initial cell numbers. The nuclear area was measured area-analytically with the Quantimet, the determination of cell population was measured linear-analytically using the Digiscan. Nuclear size remains constant in a cell culture of 104 up to 8.3 × 104 cells ml, which corresponds to a cell density of about 25–160 cells/unit. A significant diminution in mean nuclear size of the cell nucleus occurs in the case of increased cell densities of 215 and 277 cells/unit, corresponding to a cell culture of 2.5 × 105 and 7.3 × 105 cells ml. This diminution may be connected with the accumulation of Gl cell nuclei in cultures with contact-dependent growth inhibition.
Correlation between the structure of the wall of the bone lacuna and the localization of the osteocyte within this lacuna
Authors: Pawlicki Roman
Published: February 2009

A correlation between the structure of the wall of the bone lacuna and the localization of the osteocyte within this lacuna was the object of investigation under light and electron microscopes. On the basis of the structural divergences detected, the author distinguished zones A and B in the osteocyte situated in the lacuna. Zone B is characterized by a parallel, compact system of collagen fibrils which form a characteristic ridge in the lacunar wall, a continuous demarcating line bordering this wall, the osteocyte cytoplasm in this part lying far from the lacuna wall and surrounding the nucleus with a narrow band, and the pericellular space which is wide here and containing a large number of mucopoly-saccharides. This picture may correspond to the area of temporary non-reactivity of the osteocyte. Zone A is characterized by a loosened and disordered system of collagen fibrils forming the lacunar wall. These fibrils being exposed in this place by nature, the demarcating line bordering the lacunar wall is broken in some places, the osteocyte cytoplasm is considerably concentrated around the nucleus and contains a large number of organelles. It also lies closer to the lacunar wall, which results in a decreased width of the pericellular space and a diminished mucopolysaccharide content in this part of the lacuna. Structural variations in the lacuna wall and its space (zones A and B) observed in the images obtained with a normal bone in the light and electron microscopes show their immediate dependence on the position of the osteocyte in the lacuna, which may be associated with the osteocyte activity. On the other hand, the occurrence of significant changes in a definite zone (zone A) of the lacuna only points to the oriented character of this activity.
Cilia-forming potentials of endocrine organs originating from the foregut
Authors: Kapa Eszter , Rados I. , Csaba G.
Published: February 2009

Cilia were found in intracellular localizations or on the surface of certain cells of frog thymus and chicken parathyroid gland and ultimobranchial body. The experimental observations suggest that ciliogenesis is probably a general property of branchiogenic epithelium, which either persists, or can be activated by certain influences after the functional differentiation of endocrine organs arising from the foregut.
Variations in kidney ultrastructure with a variety of paraformaldehyde fixation techniques
Authors: Schmidt Melvin E. , Abdelbaki Yahya Z. , Tu Anthony T.
Published: February 2009

Variations in fine structure of glomeruli and proximal tubules were studied to determine the results of several fixation techniques with paraformaldehyde. Immersion fixation techniques generally resulted in poor fixation, while the quality of fixation by perfusion was directly related to the concentration of the paraformaldehyde. The best technique was fixation by perfusion and immersion in 3% paraformaldehyde for 2 h followed by a post-fixation in 1 % OsO4 for 1 h. Intracellular edema was noted in all epithelial, mesangial and proximal tubular cells that were from poorly fixed kidneys. Swollen mitochondria and the dilated endoplasmic reticulum were common in many of those cells. Mesangial and proximal tubular cells were the first to swell. Poor fixation produced the early stages of autolysis. The criteria for good paraformaldehyde fixation are discussed.
Seasonal study of the adrenal gland of some Indian avian species
Authors: Vyas D.K. , Jacob Dennis
Published: February 2009

Adrenal glands of eight Indian species of birds, namely Columba livia, Passer domesticus, Corvus splendens, Acridotheres tristis, Acridotheres ginginianus, Milvus migrans, Francolinus pondicerianus and Bubulcus ibis were examined during the sexually active and inactive phases of their annual reproductive cycles. Excepting A ginginianus and M. migrans, among members of either sex of the remaining six species the weight of the adrenal gland increases during the period of sexual activity. Histologically, the interrenal tissue of these birds could be divided into a peripheral subcapsular zone and a central zone. The cytochemical content of these two zones varies between sexual activity and inactivity. In sexually active birds of both sexes, interrenal cells of the central zone exhibit an increased concentration of alkaline phosphatase, glycogen, acid mucopolysaccharides and gross lipids, while in the subcapsular interrenal cells there is a prominent increase of ascorbic acid content. Cytochemical contents of chromaffin cells remain unchanged except acid phosphatase, which increases during the sexually active phase.
Der ”Surface-Coat” embryonaler Hohlräume (Rathke-Tasche und Neuralrohr) der Maus
Authors: Seinsch W.
Published: February 2009

Mouse embryos, gestation days 10 and 11, were fixed by the method of Luft (ruthenium red). At the ultrastructural level, luminal epithelial cell membranes of Rathke’s pouch and the neural tube were coated with a continuous, electron-dense layer of 100–700 Å thickness. The biological property of this surface coat is discussed.
Studies on the structure and function of Gomori-positive glial cells in the rat hypothalamus
Authors: Goldgefter L.
Published: February 2009

Electron-microscopic, histochemical and endocrinologic study of aldehyde-fuchsin-positive (Gomori-positive; GP) grains of rat brain periventricular glia (GP glia) was carried out. GP structures appear as a population of osmiophilic particles, which is heterogeneous in both shape and size. Laminar structures interspersed with fine granular material were seen in the GP granules. No activity of the lysosomal and mitochondrial enzymes could be observed. The reaction for peroxidase was also negative. The GP material was stained with PAS and Ziehl-Nielsen. There are apparently no lipoid inclusions in the GP grains. The primary red-orange fluorescence distinguishes the GP glia from other structures in the rat brain. So GP grains are a specific cytoplasmic formation having some similarity to lipofuscin. There was a considerable decrease in GP grains after administration of estradiol in ovariectomized rats and also in pregnant rats. Dopamine administration and starvation caused some reduction in GP grains. In the rat hypothalamus, distribution of the main mass of GP glia corresponds with the so-called hypophysiotropic area. The possible participation of GP glia in the neuroendo-crinological process is discussed.
Cytological identification of sex in pig embryos at indifferent gonadal stages
Authors: Pelliniemi Lauri J. , Salonius Anna-Liisa
Published: February 2009

A reliable method of sex identification in pig embryos at sexually indifferent and early differentiated gonadal stages (age 21–26 days) was developed in association with ultrastructural studies on gonadal development and differentiation. The routine carbolfuchsin staining for the sex chromatin and the quinacrine mustard dihydrochloride staining for the fluorescent Y chromosome were not successful when applied to interphase cells. Therefore, it was necessary to develop a method for complete chromosome preparations. Head, heart and liver proved to have a sufficiently high spontaneous mitotic rate without any mitogenic stimulation. The tissues were suspended in the culture medium. Optimal conditions for colchicine treatment and hypotonization were tested and the details of the procedure are reported. This direct method yielded adequate metaphase plates for chromosome analyses in pig embryos. Because no culturing is used, the method is rapid and artefactual changes in the chromosomes during stimulated cell divisions in vitro are avoided.
Sexual dimorphism in the basilar part of the occipital bone of the dog (Canis familiaris)
Authors: The T.L. , Trouth C.O.
Published: February 2009

Sexual dimorphism in the surface markings of the basilar part of the occipital bone of 34 male and 46 female dog’s skulls were studied with the following results: 1 of the 34 male skulls showed a female type surface marking, 4 of the 46 female skulls showed surface markings of the opposite sex, while 2 of the male and 3 of the female skulls could not be classified as belonging to either type, so that 10 out of the 80 skulls could not be identified correctly, indicating that 87.5% of the skulls could be identified positively. Considering that there are hardly any sexual differences in the other surface markings or in the dentition of the dog’s skull, these findings may be of some help in sexing the skull of the dog.
Non-specific esterases in the gustatory epithelia of man and dog
Authors: Rakhawy M.T.
Published: February 2009

(1) Simple esterase activity has been demonstrated in the gustatory epithelium of man and dog by the simultaneous coupling azo dye technique using α-naphthol and naphthol As acetate. Unfixed cryostat and fixed paraffin sections were used. (2) A peculiar pattern of simple esterase activity was encountered in which – contrary to what was to be expected – the taste bud-carrying papillae showed a very poor reaction while there was a gradual increase in the enzyme intensity as the epithelium was traced away from these papillae. (3) It seems that among the reported differences between simple esterases and cholinesterases is this differential activity in relation to the gemmal system. (4) A peculiar difference in the enzyme activity was reported between the unfixed cryostat and the fixed paraffin sections in the human material.
An ultrastructural study of the relationship between pericytes and cerebral macrophages
Authors: Boya J.
Published: February 2009

We studied, with the electron microscope, the normal cerebral cortex of white rats and zones adjacent to puncture wounds. The data obtained in this study, demonstrated the passage of pericytes to the nervous tissue, after the rupture of the basal membrane, and their transformation into macrophages. We suggest the possibility of the transformation of the pericytes into microglial cells.
Arterial supply to the hypogastric and presacral nerves
Authors: Shehata Ramzy
Published: February 2009

The hypogastric nerves take an arterial supply from the internal iliac artery either directly or from one of its main branches close to its origin from the parent trunk. Sometimes the supply is from the lower end of the common iliac artery. In half the cases examined the presacral nerve takes an arterial supply from the aorta at its bifurcation.
Studies on the oogonial cycle in Puntius ticto (Ham.)
Authors: Kapoor Prakash
Published: February 2009

Histologically, the ovary of Puntius ticto (Ham.) is covered with three layers, namely peritoneum, tunica albuginea and germinal epithelium. The last two give rise to the ovigerous nests in the ovocoel. The new crop of oocytes is either derived from the germ cells present in the ovigerous nests, or from the epithelium of the outer wall of the ovary, or from the epithelium of the ovigerous folds.
Observations on the effects of α-chlorhydrin on the tested and pituitary gonadotrophs of gerbil (Meriones hurrianae) and rat
Authors: Dixit V.P. , Lohiya N.K.
Published: February 2009

(1) Lower doses of α-chlorhydrin caused high selectivity of lesions in the seminiferous tubule of rat and gerbil. (2) The seminiferous epithelium became systematically depleted of spermatogonia, spermatocytes, spermatids and finally spermatozoa in this sequence. (3) The suppression of RNA concentration in the testes and seminal vesicle is conspicuous. (4) The growth of androgen-dependent organs, i.e. seminal vesicles, ventral prostate, epididymes and perineal complex, is suppressed. (5) These effects are reversible. Repopulation of testis tubules occurs followed by a 40-day recovery period in rat and gerbil. (6) α-Chlorhydrin administration brings about hypertrophy of pituitary gonadotrophs which is also reflected in the increased basophilic cell percentage (control: 15.5% α-chlorhydrin: 21.5%; p < 0.01).
Ultrastructural study of the adenohypophysis of the Chinese hamster
Authors: Deslex P. , Rossi G.L. , Probst D.
Published: February 2009

The adenohypophysis of normal Chinese hamsters of both sexes was examined ultrastructurally. Organs were fixed by intravascular perfusion with S-collidine-buffered glutaraldehyde solution. Seven types of cells were differentiated and, according to morphological characteristics, classified as (1) mammotropes, with very large (400–800 nm) and polymorphous secretory granules; (2) somatotropes, either in the storage phase with numerous large, dense granules (average 300 nm), or in the hormone synthesis phase, with abundant endoplasmic reticulum and large Golgi apparatus; (3) corticotropes, with irregular cell shape, and granules (average 160 nm) arranged in lines parallel to the cell membrane; (4) FSH gonadotropes, with abundant and dilated endoplasmic reticulum, and granules (190–320 nm) uniformly distributed in the cytoplasm; (5) LH gonadotropes, with granules (120–220 nm) of varied density; (6) thyrotropes, with irregular cell shape and very small granules (120–160 nm), and (7) agranulated cells. The ultrastructure of the adenohypophysis of the Chinese hamster corresponds closely with observations reported in rats, mice and Syrian hamsters.
Effect of triamcinolone on the ultrastructure of mouse hepatocytes
Authors: Ludatscher Ruth , Silbermann Michael
Published: February 2009

Premature female mice were injected daily with 1.5 mg/kg body weight of triamcinolone diacetate for 10 and 21 consecutive days. Electron-microscopic study of hepatocytes indicated the formation of ‘giant’ mitochondria concomitant with a marked increase in the number and size of lipid droplets. Hypertrophied mitochondria and enlarged lipid droplets were found to be in a close topographical association. The mechanism of mitochondrial enlargement is discussed as well as the latters’ role in the hepatocytes’ lipid metabolism.
Study in the changes of the proportions and numbers of the various glial cell types in the spinal cord of neonatal and young adult rats
Authors: Ling E.A.
Published: February 2009

Glioblasts, astrocytes, microglia and the three classes of oligodendrocytes were enumerated in the grey and white matter of the spinal cord of rats of various ages. Both regions showed fairly similar results. Glioblasts, which made up the major glial population in the newborn rats, declined steadily with age and their number became negligible by 22 days post natum. They were absent in the young adult rats (aged 70 days). Contrary to this, the major glial types increased rapidly with age, the increase being most drastic in the oligodendrocy tic population. The growth continued through about 22 days after birth and became more or less stabilized thereafter. Of the three classes of oligodendrocytes, the light cells appeared to develop first, followed by the medium dense cells and subsequently the dark ones. While there was a gradual disappearance of the light and medium dense cells with age, there was an accumulation of the dark cells, so that they were predominant in the spinal cord of the young adult rats.
Anatomical study of the cervical sympathetic trunk and ganglia in the albino rat (Mus norvegicus albinus)
Authors: Hedger John H. , Webber Richar H.
Published: February 2009

Nine adult albino rats of both sexes were studied. 16 sympathetic trunks and ganglia were dissected in detail in eight rats. The right and left superior cervical ganglion and the sympathetic trunk below the ganglion were removed from an additional rat. The cell bodies of these ganglia and the axons of the trunks were counted with the aid of light and electron microscopy. Considering the number and location of ganglia and patterns of branching, the rat’s cervical sympathetic nervous system compares closely with man’s. There appears to be a relationship between body size and myelination of preganglionic neurons in the cervical sympathetic trunks, with smaller animals having the least number of myelinated fibers.
Preparation of fresh-frozen dried ultrathin sections by drying without vacuum
Authors: Takaya Kenichi
Published: February 2009

Fresh-frozen dried ultrathin sections were prepared without fixation, embedding or staining. Small blocks of tissues were ch’lled by making contact with copper blocks precooled with liquid nitrogen according to a procedure modified from that of Christen-sen. Sections were cut at -95 °C with a Reichert Um 2 ultramicrotome fitted with cryoaccessories, using dry glass knives. The sections were dried for 15 min or more on formvar-coated grids by a flow of dry nitrogen gas at -95 °C in a newly devised glass chamber placed in the cryokit compartment. The sections showed only a few holes attributable to ice crystal formation. Holes were found in the intercellular spaces as well as within cells. The sections were observed without staining and gave enough contrast to permit recognition of organelles such as nucleus, perinuclear cisternae, nucleolus, interchromatin granules, perichromatinic granules and secretory granules in the pancreatic exocrine cells. In the basal part of the proximal convoluted tubules of mouse kidney, abundant mitochondria were seen. Mitochondrial cristae and lines corresponding to the basal infoldings of the renal convoluted tubules were less dense than their surroundings. This method can yield ultrathin sections lending themselves to investigations of the distribution of elements with electron-probe X-ray microanalyzer and of diffusible substances by dry-mount autoradiography at the electron-microscopic level.
Lichtoptische und rasterelektronenmikroskopische Untersuchungen zur Wandstruktur der Cisterna chyli des Menschen
Authors: Lenz W. , Huth F.
Published: February 2009

Comparing light and scanning electron microscopy of a chronically lympho-static and two normal cisternae chyli made visible a normally folded and smoothened (under load) cisternal wall. Different orifices of the supplying lymph-collecting vessels with varying valve structures were seen. The functional meaning of the orifice types and of the valves for the uptake of lymph and chylus into the cisterna as well as for the blockage of lymphatic reflux out of the filled cisterna were discussed.
Die orbitotemporale Region im Schädel von Chelydra serpentina Linnaeus (Chelonia) und Lacerta sicula Rafinesque (Lacertilia)
Authors: Rieppel Olivier
Published: February 2009

An analysis of the ontogenesis of the chondrocran¡um gives the following homologies in the skull of Lacerta and Chelydra: Chelydra Lacerta Pila metoptica subiculum infundibuli cartilago hypochiasmatica Pila antotica pila antotica pila accessoriaDorsal border of planum supraseptale part of the taenia marginalis closing the fenestra epioptica dorsally Caudal process of the pila antotica dorsal to the incisura prootica part of the taenia marginalis running from the pila antotica to the ear capsule It is shown that the extracranial position of the cavum epiptericum in Lacerta corresponds to the stage of maximal development of the chondrocranium in Chelydra. But further development brings about a dermal sidewall in the orbitotemporal region, built up by descending parietal flanges which incorporate the epipterygoid. This not only allows the pila antotica to degenerate but also incorporates the cavum in the cranial cavity.
Morphological and histological study of the gastro-intestinal tract of the ferret
Authors: Poddar S. , Murgatroyd L.
Published: February 2009

The morphology and histology of the post-pharyngeal part of the gastrointestinal tract of the ferret were studied. The oesophagus was a distensible muscular tube. Its mucosa was lined by keratinizing stratified squamous epithelium. The muscle coat was striated throughout except near the cardia. A cardiac sphincter was present. The stomach was morphologically and histologically very similar to that of man. The duodenum appeared C-shaped and had a mesoduodenum. The bile and pancreatic ducts formed a common duct in the wall of the duodenum. The sphincter of Oddi was present. Brunner’s glands were present in the pyloric part of the stomach, and up to the common opening of the bile and pancreatic ducts in the duodenum. The intestine could be differentiated macroscopically and microscopically into small and large intestines. The small intestine distal to the duodenum formed coiled tubes suspended by a mesentery. It was not possible morphologically to differentiate jejunum and ileum. Histologically, however, the distal portion was identifiable as ileum by increasing numbers of goblet cells, and Peyer’s patches in the submucosa. Villi were present in the mucosa throughout but there was no spiral or circular fold. The large intestine was a straight dilated tube lying in the left flank and extending from the splenic flexure to the anus in the median plane. It was suspended by a short mesocolon except for the rectal portion in the pelvis. The ileo-colic junction was differentiated morphologically and histologically. There was no caecum, appendix, taeniae coli or appendices epiploicae. The large intestine was not differentiated topographically into ascending, transverse and descending colon.
Effects of hypophysectomy and short- and long-term propylthiouracil treatment on the rat thyroid
Authors: Gaal J.M. , Kovacs K. , Sellers E.A.
Published: February 2009

The follicular architecture of the thyroid gland of the rat following experimentally induced states of hypo- and hyperactivity was investigated by scanning electron microscopy and the findings correlated with both light and transmission electron-microscopic observations. By scanning electron microscopy, the microvilli on the apical surfaces of the follicular cells showed the most striking changes; following hypophysectomy, the cells were flattened and the microvilli had decreased in both size and number, whereas following propylthiouracil (PTU) administration the epithelial cells were enlarged, and marked hyperplasia and hypertrophy of the microvilli was present. Of particular interest is that the changes observed following PTU appeared to be identical in short- and long-term PTU-treated rats. Similarly, the heterogeneity of the follicular cells observed within the follicles was maintained under the various experimental conditions. Although the functional significance of these observations is not quite clear, it appears justifiable to assume that a reduction of luminal surface area of the follicular epithelial cell may hinder, whereas an increase may facilitate transport process across the apical cell membrane.
Faserkristallisation, chondroide und ossale Mineralisation bei der desmalen Osteogenese und in der Zwischenwirbelscheibe
Authors: Knese K.-H.
Published: February 2009

We reported on similar findings concerning the intercellular substances in the early desmal osteogenesis in cattle fetuses and rats and in the intervertebral disc of cats. In both regions fibrils change their structure. In early desmal osteogenesis the bone fibrils are synthetized by osteoblasts, derived from mesenchymal cells. Later the fibrillar structure is lost and substituted by a homogenous substance. Chondroid starlike mineral deposits which are composed of needles appear in the vicinity of the cells. The chondral needles are longer and smaller than those in the bone. Finally the chondral needles are removed by mineraloclasts. During the next step fibrils reappear. They are accompanied by needles in their longitudinal axis. In adult cat the fibrils of intervertebral disc cross directly in bone. The fibrils of fibrocartilage are partly swollen and escorted by starlike mineral deposits. Between the bone fibrils partly amorphous mineral deposits are found generally needle-like along the fibrils. The nucleation of minerals takes place at random. The crystal growth is correlated to the structure and composition of organic intercellular substances and their morphological shape differs correspondingly, being chondroid in the fashion of stars, amorphous and osseous when in contact and parallel to the fibrils.
Effects of intense exercise on intracellular glycogen and fat in pigeon pectoralis
Authors: Parker G.H. , George J.C.
Published: February 2009

The pigeon pectoralis muscle was electrically stimulated in vivo at a high intensity of 25 V and the intracellular glycogen and fat reserves of the muscle examined histochemically to determine the pattern of substrate utilization in the component broad white and narrow red fibre types during the intense flight-simulated exercise. 4 h of continuous stimulation resulted in the depletion of intracellular glycogen from both fibre types and a simultaneous reduction in the intracellular fat stores of the red fibres. While glycogen provides the only source of energy for the white fibres, glycogen as well as fat serves as fuel for the red fibres. It is postulated that, though fat is the major fuel for the red fibres, their glycogen reserves are utilized to ensure a steady supply of oxalo-acetate essential in the oxidation of fatty acids via the Krebs cycle, and that fatty acid catabolism helps to maintain gluconeogenesis.
Development and peripheral innervation of the palatal muscles
Authors: Doménech-Ratto G.D.
Published: February 2009

Following the observation of 51 embryos and human fetuses of between 9 and 190 mm vertex/coccyx length, cut transversally, frontally, or sagittally, depending on the case, and coloured with HE, Azan, or by the Bielschowsky method, we studied the development, and peripheral innervation of the palatal muscles. We reached a series of conclusions which we put forward in this paper. The m. tensor veli palatini is the one which develops earliest. It derives from the same blastematic mass as the muscles of mastication, and it is innervated by a branch of the n. mandibularis. The m. levator veli palatini and m. pharyngopalatinus coincide chronologically with the appearance of the m. cephalopharyngeus. They derive from the pharyngeal musculature, and are innervated by fibres proceeding from the n. glossopharyngeus, in the case of the first one, and, in the case of the second, by direct branches from the n. glossopharyngeus and the n. vagus, which penetrate the muscle directly, without prior contact with any nerve plexus. The m. uvulae is first formed, at the time the palatine processes close. In the first place, two outlines may be seen; but after 50 mm approximately it is formed by one muscle only, on the medial line; it is innervated by branches which proceed from the posterior n. palatinus. The m. glossopalatinus is the last to appear. It is closely linked to the musculature of the tongue and, therefore, we think that it derives from the hypobranchial musculature, and that it is innervated in the body of the tongue itself, by means of the n. hypoglossus.
Comparative morphological and histochemical aspects of selected arteries in the chicken and rat
Authors: Fischer Vernon W. , Kloetzer William S. , Baker Kevin E.
Published: February 2009

Morphologic and histochemical characteristics of selected portions of normal arteries from two species known to differ in susceptibility to vascular disease were examined. Arteries were classified as predominantly elastic, muscular or complex. Species differences in the structural organization of the abdominal aortic segment were observed. Arterial mucopolysaccharides were stained more intensely in the tunica intima and media of chicken vessels than within those of the rat, and tended to be most concentrated in proximity of the internal elastic membrane. Histochemical procedures for the demonstration of enzymatic activity revealed inter-and intraspecies variations in vascular metabolism. Pronounced differences in reaction intensity for hydroxybutyrate dehydrogenase and malic enzyme, affecting chicken and rat coronary arteries, were noted. In contrast, these vessels displayed only minimal activity for acid phosphatase. Marked endothelial deposition of alkaline phosphatase reaction products in the arteries of the chicken was demonstrated, while this enzyme’s activity in the vessels of the rat was restricted to the tunica adventitia. The implications of these structural and histochemical factors with regard to vascular susceptibility to disease were discussed.
Angioarchitektonik der Medulla oblongata des Meerschweinchens
Authors: Brenner Jürgen
Published: February 2009

The angioarchitectonic regions in the medulla oblongata and the midbrain of 14 grown-up guinea pigs are discribed. According to direction and number of the supplying arteries, three sections are distinguished. The medial part is supplied worst. It contains the medial row of the nuclei of the cranial nerves. The more lateral parts have always double or treble supplies. They are distinguished by a high capillary density. Those parts are associated with the medullar nuclei of the cranial nerves.
The effect of alcohol on the pigment epithelium of the chick
Authors: Yew David T , Wong Ling
Published: February 2009

The effect of alcohol on the pigment epithelium of the chicken was studied. In the treated animals, the apical microvilli were found to cohere into sheets and there was also proliferation of endoplasmic reticulum, myeloid bodies and dense bodies.
Infant primate larynx: developmental histology
Authors: Sutton D. , Taylor E.M. , Lindeman R.C.
Published: February 2009

Laryngeal epithelium of monkeys (M. mulatta, M. nemestrina) ranging in age from late fetal to adult was found to undergo the following developmental changes: (1) progressive elaboration of commissural epithelium prenatally, reaching the adult form of pseudo-stratified columnar ciliated epithelium early in the postnatal period; (2) vocal process epithelium changing from cuboid to stratified squamous tissue during the late prenatal period, and (3) progressive increments in overall epithelial thickness during development, reaching a maximum in the early postnatal period. Chondrocyte density of the cricoid and thyroid cartilage decreased during the late prenatal period, reaching the adult form at the neonatal stage. The evidence suggests that mechanical or metaplastic stresses do not determine the observed tissue changes.
Veränderungen des Kleinhirns der Ratte durch Aktinomycin während der Postnatalzeit
Authors: Raedler Elisabeth
Published: February 2009

A single dose of actinomycin was applied to young Wistar albino rats in the critical phase of their cerebellar development. The morphological alterations of the cerebellar cortex were studied by means of light and electron microscopy on several postnatal days. The cell types of the cerebellar cortex reacted in different ways toward the noxious substance according to their stage of development. The acute alterations consisted of an edematous reaction of the neuronal and glial perikarya (light degeneration) and a shrinkage of the neurons (dark degeneration). A massive intercellular edema and a rarefaction of glia cells as well as the Purkinje cell fibres proved to be the long-term damage. This pattern of the alteration was discussed regarding the chemodifferentiation of the cells of the cerebellar cortex, the onset of cerebellar function on day 14, and the establishment of a neuroglial functional unit.
Electron-microscopic studies of the innervation of the pulmonary veins of the mouse
Authors: Hung Kuen-Shan , Loosli Clayton G.
Published: February 2009

The innervation of the pulmonary veins was studied with electron microscopy. The adrenergic and cholinergic nerves were differentiated with potassium permanganate fixation. All three layers of the venous wall, namely, the tunica intima, media and adventitia, contained unmyelinated axons. Adrenergic and cholinergic axons were located near the cardiac muscle in the tunica media and near the smooth muscle in the tunica intima. The morphological relationships may explain the pharmacological and electrophysiological responses of the large pulmonary veins observed by others.
Verteilung und Aktivitäten hydrolytischer Enzyme in den apokrinen Hautdrüsen des Hausschweines
Authors: Meyer W. , Neurand K.
Published: February 2009

The distribution and activities of several hydrolytic enzymes have been determined for the apocrine ‘sweat glands’ of the domestic pig. The results are discussed in relation to similar investigations into the human apocrine sweat glands.
Anzahl und Lokalisation der Peyerschen Platten im Dünndarm des Kaninchens (Oryctolagus cuniculus)
Authors: Sackmann W.
Published: February 2009

In the rabbit intestine Peyer’s patches can easily be distinguished. They are found in the jejunum and ileum, but not in the duodenum. The highest number observed is seven. In most animals the first, i.e. proximally situated patch has a rather well-defined place in the beginning of the jejunum; similarly, the last, i.e. distally situated one mostly has its place in the end of the ileum. The demarcation of the three classical sections of the small intestine is discussed from a comparative viewpoint with special criticism as to what is called ileum in man.
Ultrastruktur der Beziehungen zwischen interstitiellen Zellen und Myokardzellen im Herzen von Säugetieren
Authors: Heine H. , Schaeg G.
Published: February 2009

By combination of light, electron-microscopical and histochemical findings in the myocardium of dog and mice, the hypothesis of an intimate contact between a widely branched interstitial cell type, rich in proteoglycans, and myocardial cells could be strengthened. The branches seem to penetrate the transversal tubular system of the myocardial cells. Functionally, this interstitial (mast cell-like) cell type might influence via proteoglycans – delivered into the transversal tubuli – the excitation phenomena of the myocardial cell membrane. One of the earliest pathomorphological changes in the myocardium, as revealed by the light-microscope, is the disengagement of these interstitial cells and the myocardial cells. From this point of view the genesis of myocardial cell necrosis has been discussed.
Kinetics of luminal secretions in the female reproductive tract
Authors: Hafez E.S.E.
Published: February 2009

The epithelium of the female reproductive tract undergoes cyclic morphologic alterations in cell shape, apical microvilli, ciliation, and secretion. These changes are hormone-dependent. The endometrial fluid is made of (a) components from the transudation of the blood serum and (b) protein, carbohydrate and other metabolites synthesized within the endometrial cells and discharged through the apical cell membrane. Endometrial cells have several mechanisms of transport processes across the plasma membrane. These processes regulate cellular volume, nutrition, excretion and communication along the surface of the cell as well as the intra-cellular and extracellular communication. The endometrial secretions play a major role in the capacitation of spermatozoa, and the nutrition of the blastocyst.
Staining of rabbit eosinophil and pseudoeosinophil leukocytes
Authors: Shanklin William M. , Sheppard Benjamin , Burke, jr. George W.
Published: February 2009

Air-dried rabbit blood was stained by HE, PAS and a modification of the Undritz II method. Eosin stained granules red in the eosinophil leukocytes. PAS was negative and the modified Undritz method failed to give consistent results. Cells with eosinophilic granules appeared in the corneal stroma 1 h after removing the corneal epithelium. They were stained red consistently by both eosin and the modified Undritz method. Electron micrographs failed to demonstrate crystalloids in their granules. Because of the staining characteristics and the lack of crystalloids in their granules these cells were classified as pseudoeosinophil leukocytes. The electron micrographs showed some glycogen 12 h after denuding the cornea, however, glycogen was not well stained by PAS until 18 h after denuding.
Root formation in ectopically transplanted teeth of the frog, Ranapipiens
Authors: Howes, jr. Robert I.
Published: February 2009

In order to determine the intrinsic (genetic) and extrinsic (functional) parts of the naturally ankylosed tooth, a qualitative study of the development and fate of tooth buds transplanted individually or within the premaxilla was carried out. These teeth were transplanted as autografts during crown formation. They were placed in either the anterior chamber of the eye or in a dorsal subcutaneous site. Most of the 163 transplants survived and were examined at intervals from 0 to 180 days by gross, histologic and microradiographic methods. Tooth buds transplanted with or without the premaxilla were capable of growth to normal size and shape. Lack of underlying bone with which to ankylose and lack of normal oral environment and function did not prevent formation of a normal-sized root area. The root area was composed of dentin and covered by a solid, undisrupted Hertwig’s epithelial root sheath which appeared to mold the root. Calcified tissue formed on the outside surface of dentin only when the root sheath was accidentally torn during transplantation.
Unterschiede in der Färbbarkeit der Purkinje-Zellen
Authors: Meitner E.R.
Published: February 2009

Regarding the different stainability when using the Luxol fast blue method, two kinds of Purkinje cells of the rat are described: Luxol-positive and Luxol-negative cells. Since, by this method, phospholipids are demonstrated, the author suggests the prospective varying functional condition of these cells. Different tinction of Purkinje cells has been confirmed also by other methods (gallocyanin-chromalaun, thionine, toluidine blue, lithium-haematoxylin, chromalaun-haematoxylin-phloxine and acid phosphatase) in both animal and human material. After 96 h of immobilization the different stainability of Purkinje cells becomes more marked, which phenomenon can be as well explained with regard to the functional point of view. Similar differences, though less marked, were found also in neurosecretory cells of the nucleus supra-opticus of the rat and in the nuclear region of the ganglion semilunare Gasseri cells in man. Finally, the author refers to the relations between the Luxol blue staining method and Baker’s method employing acid haematoxylin for demonstration of phospholipids in certain kinds of nervous system cells, taking into consideration Kroon’s findings.
Fine-structure study of the parathyroid in the gerbil, Meriones unguiculatus
Authors: Kapur Shakti P.
Published: February 2009

A fine-structure study of the parathyroid proper and adjacent tissues has been performed in the gerbils. The chief cells were observed in three phases of the secretory cycle. The resting chief cells contained prominent lipid droplets, mitochondria and an atrophied Golgi apparatus in a finely granular cytoplasm. The intermediate-phase chief cells were also rich in lipid but showed an organelle assembly which is much less developed than in the actively secreting cells. The active chief cells possessed a noncisternal rough endoplasmic reticulum, located often in close proximity of the mitochondria. A prominent Golgi apparatus, numerous pro-secretory granules and lysosomes are characteristic of the active cells. The significance of these morphological variations is discussed. Large mitochondria-rich cells, akin to oxyphil cells were observed in the tissue adjacent to the parathyroid proper.
Ultrastructure of the human pharyngeal hypophysis
Authors: González Carlos B. , Valdés Gustavo F. , Ciocca Daniel R.
Published: February 2009

Four types of secretory cells have been distinguished in the human pharyngeal hypophysis. Type I cells contain granules of about 70–90 nm in diameter; type II cells are the most numerous and are loaded with granules ranging in size between 100 and 200 nm. In type III cells the size of the granules ranges between 150 and 250 nm in diameter. Type IV cells contain the largest secretory granules (250–400 nm). In addition, there is a type of cell lacking secretory granules and which has been regarded as interstitial cell (type V). The different cell types are arranged in clusters which, in turn, are surrounded by numerous blood capillaries. A few nerve fibres have been observed within the gland. These fibres make synaptoid contacts with type II cells. The ultrastructural analysis of the human pharyngeal hypophysis strongly suggests that this formation is an endocrine gland with distinct characteristics and with a functional role probably different from that of the sellar hypophysis.
Morphological and functional aspects of the arrangement of connective tissue and muscle fibres in the tail of the Mexican axolotl, Siredon mexicanum (Shaw) (Amphibia, Urodela)
Authors: Willemse J.J.
Published: February 2009

In the lateral musculature of the axolotl tail a multipennate arrangement of muscle fibres is found in the 3rd postanal myomere and all following myomeres. This arrangement appears in larval stages as soon as the myomeres concerned are fully differentiated. Within a myomere a uniform degree of contraction of the muscle fibres may be achieved either by helical arrangement as seen in Teleosts, by diminishing fibre length in medial direction or by a combination of both phenomena. The relation between muscle fibre length and angle of insertion in the myomeres showing pennate arrangement is approximated by the Benninghoff and Roll-häuser equation but the values recorded deviated systematically from the values calculated. In the rather slender tail of the axolotl the transition from the helical or parallel fibre system into the pennate arrangement will be in favour of the development of relatively strong bending moments in the region concerned while a reasonable uniformity of the rate of contraction is maintained.
The effects of denervation on the localization of ▵5-3β-hydroxysteroid dehydrogenase activity in the rat ovary during pregnancy
Authors: Burden Hubert W. , Irvin I. , Lawrence, jr E.
Published: February 2009

The effect of denervation on △5-3β-hydroxysteroid dehydrogenase (3β-HSD) activity with pregnenolone as substrate was studied during pregnancy. The enzyme activity, that is interpreted as the capacity to secrete progesterone, was studied in both control and experimental pregnant rats. The ovaries of experimental rats were denervated 96 h prior to sacrifice. Denervation during early pregnancy did not affect 3β-HSD activity in the interstitial gland (IG) and corpus luteum (CL). However, denervation resulted in decreased activity in both the IG and CL on days 10, 14 and 18. This reduced activity is interpreted as a decreased capacity of denervated ovaries to synthesize progesterone at this time in pregnancy.
Postnatal development of vagina, clitoris and urethral glands of the golden hamster
Authors: Hisano N.
Published: February 2009

We have made a histological study of the postnatal development of the clitoris, preputial glands, urethral glands and vagina of the golden hamster. The ‘phallic groove’ of the clitoris is closed at 10 days of life, then the urethra has a cuboidal stratified, a stratified squamous and a stratified keratinized epithelium. The preputial glands are composed of branched saccular glands. These glands develop, with few changes during their maturation period. Formation of the urethral glands begins at 5 days and the alveoli are fully developed at puberty. The hamster vagina has two origins; the upper part is Müllerian, the caudal part is sinusal. The wall of the Müllerian vagina has a cylindrical epithelium at birth, which becomes ‘double epithelium’ at puberty and thereafter changes cyclically in connection with the estrous cycle. The sinusal vagina is solid at birth, its lumen being formed in the first 10 days of life and its wall having a cuboidal stratified epithelium. At 15 days it becomes a stratified keratinized epithelium, which will later line the vaginal pouch. At the 5th day, an ectodermic invagination (stratified keratinized epithelium) is observed in the zone of the future introitus. At the time of vaginal opening this zone forms the distal segment.