bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of Rehabilitation on the Jaws and Teeth of Protein-Deficient and Calorie-Deficient Pigs
Authors: Luke D.A. , Tonge C.H. , Reid D.J.
Published: July 2008

The growth of the jaws and teeth was examined in pigs which had been fed protein-deficient and calorie-deficient diets for the first year of life and thereafter allowed unlimited food. After 2 years of rehabilitation, jaw size had almost reached that of well-fed controls, although in the mandible the labial alveolar process remained abnormally proclined and in both jaws the crowns of third permanent molars were smaller than in control animals. Calorie-deficient pigs did not recover as well as did protein-deficient animals. Pigs fed a calorie-deficient diet for the first 2 years of life before rehabilitation also made a good recovery and were only slightly smaller in most dimensions than those undernourished for 1 year and then rehabilitated. Despite the excellent recovery in jaw dimensions, some malposition of teeth persisted after rehabilitation, especially in animals which had been undernourished for 2 years.
Dense Bodies in Bronchiolar Ciliated Cells of Rats
Authors: Baert J.H. , Vandenberghe M.P.
Published: July 2008

The bronchiolar ciliated cells of rats usually contain two large electron-dense bodies which are individually surrounded by a unit membrane. They lie in a well-defined supranuclear position and may indent the nucleus. The dense material is digested by pepsin, suggesting it is composed of protein. The origin and function of these bodies are still unknown.
Comparison of Effect of Oestrogen on Muscle Development of Male and Female Mice
Authors: Ihemelandu E.C.
Published: July 2008

The effect of oestrogen on muscle development was determined in 8 muscles (biceps brachii, triceps brachii, common digital extensor, soleus, superficial digital flexor, cranial tibialis, gastrocnemius and long digital extensor muscles of sexually immature male and female mice. Each mouse was killed at a mature age of 16 weeks. The muscle development as determined by increase in muscle weight was significantly smaller in muscles of oestrogen-treated male and oestrogen-treated female mice as compared to the muscles of normal male and normal female mice. The muscles of normal male mice were very significantly larger than those of normal female mice. There was, on the other hand, no significant difference between the muscle mass of oestrogen-treated male and oestrogen-treated female mice. This indicated that the smaller muscle mass of normal female mice when compared to normal male mice was connected with inhibitory effect of oestrogen on the muscle development of female mice.
Morphology of the Second Kind of Follicle in the Guinea Pig Thyroid Gland
Authors: Juhl Marianne
Published: July 2008

The second type of follicle (S follicle) was studied in the thyroid gland of young and mature guinea pigs. A marked activity to non-specific esterase was used as a marker system for the S follicle. Usually a single S follicle was situated in the upper central two-thirds of each lobe occupying 0.5–2.7 mm of the length of the lobe. The S follicle could in both animal groups be divided into three parts, an upper, a middle, and a lower part. The upper tubular part consisted of cuboidal and cylindrical, strong-reacting cells completely separated from the thyroid follicles by connective tissue. The middle part was further subdivided into an irregular follicle without contact to the thyroid follicles, and a distended follicle with several contact areas to the thyroid follicles. An increasing amount of flattened, weak-reacting cells interpreted as thyroid follicle cells were encountered in the S follicle wall adjacent to the contact areas. In young animals the lower part had a tubular appearance like that seen in the upper part, while the lower part of the S follicle in mature animals were more follicle like.
Structure of the Prostate and the Pelvic Urethra in Barrows and the Changes Induced by Diethylstilbestrol
Authors: Lauwers H. , Simoens P. , Nicaise M. , de Vos N.R.
Published: July 2008

The anatomical and light microscopical structures of the pelvic urethra with the surrounding prostate were investigated in male pigs, which were castrated early in life and examined at slaughter weight. The general structure was regular in the caudal part, but was irregular in the cranial part. In the prostate each lobule contained a cell-rich stroma, which surrounded several glandular tubules and a few prostate ductules. The tubules were lined by low columnar cells and some reserve cells, the ductules by a low two-layered epithelium and the urethra by a transitional epithelium. Small differences in the gland structure and urethral epithelium were observed between the cranial and caudal part. Subcutaneous injection of diethylstilbestrol provoked metaplasia of the epithelium of the urethra and the ducts, while the peroral administration of diethylstilbestrol in combination with methyltestosterone resulted in an increased number of glandular tubules.
Matrixvesikel in einigen «elastischen» Organen
Authors: Nikolov S. , Gabrovska M.
Published: July 2008

Matrix vesicles (MV) have been found during normal development in the rabbit and rat aorta and pulmonary trunk as well as in the elastic cartilage of the rat external ear. In spite of the morphological variability of MV, two basic types can be ruled out: MV with dense osmiophilic content, and light or electron-translucent MV. MV of the first type are considered to be extracellular lysosomes. MV in the vessel wall are predominantly localized in the subendothelium, and the borderzones between media and endothelium or media and adventitia; in elastic cartilage they are localized near the perichondrium. Especially often they can be seen at the place of contact between elastic and other fibers of the intercellular space. They can even penetrate the elastic membranes and plates. The parts of the organs mentioned encounter higher functional demands and are more active during development and growth. The MV appear almost exclusively a short time before birth, and predominantly during the first 20–60 days of postnatal life. Their origin may be due to exocytosis and the detachment of parts (Mikroapokrinie) of endothelial cells, smooth muscle cells, fibrocytes and chondrocytes. The MV are considered to be a substrate for subsidiary extracellular mechanisms of adaptation during the normal ontogenesis of the elastic tissue of these organs.
Development and Maturation of the Bladder Epithelium of the Guinea Pig
Authors: Martin B.F. , Wong Y.C.
Published: July 2008

In the fetal guinea pig, transitional epithelium develops at a little beyond midterm of gestation from a single layer of columnar cells. Some of the cells elongate and overlap their neighbors, but remain attached to the basement membrane by fine cytoplasmic stalks. The fetal epithelial cells do not markedly vary in size. Within the basal layer, which is the site of mitotic activity, many cells are large and binucleate, which suggests that basal cell fusions occur. It is believed that these cells eventually become surface cells. The luminal membrane develops its asymmetric structure (asymmetric unit membrane; AUM) following the appearance of AUM-bound vesicles in the apical cytoplasm, indicating that they are the source of the luminal AUM. The vesicles originate in the Golgi cisternae and are initially cup-shaped. The immature surface cells are characterized by microvilli of varying density on the luminal surface. The characteristic mature surface ridges appear to develop from rows of microvilli which fuse and link with other rows to form a reticular pattern. The process commences shortly after mid-gestation. By –15 to -10 days, the majority of cells have a well-developed surface pattern. Microvilli, however, remain prevalent in some small surface cells. These are believed to be the younger surface cells derived from pyriform intermediate cells, with the surface not fully differentiated. During the first 3 postnatal weeks, the basal cell population reaches the adult level and mitotic activity declines. The epithelium also acquires its adult morphology, whilst its functional maturity is indicated by the adult distribution and content of both glycogen, which is reduced, and alkaline phosphatase, which is increased. Rejection of cells occurs both antenatally and postnatally, and is probably a consequence of excess cell production.
Histological, Histochemical and Ultrastructural Variations along the Length of the Human vas deferens before and after Puberty
Authors: Paniagua Ricardo , Regadera Javier , Nistal Manuel , Abaurrea María Asunción
Published: July 2008

Vasa deferentia of 20 human adult males and 8 children were divided into four portions (proximal, middle, distal and terminal) for histological, histochemical and ultra-structural studies. The epithelium of the adult vas deferens was formed of columnar and basal cells. Three types of columnar cells were observed: (1) principal cells with PAS-positive cytoplasmic granules (lysosomes); (2) dark or pencil cells with a dark cytoplasm and nucleoplasm and cytoplasmic lipid vacuoles, and (3) mitochondrion-rich cells with numerous mitochondria similar to those of principal cells. All these cell types showed stereocilia and irregular convoluted nuclei, some of them containing granular, PAS-positive intranuclear inclusions. Principal cells were the most frequent cell type in the proximal portion but their number gradually decreased along the length of the vas deferens, while the proportion of both pencil cells and mitochondrion-rich cells increased. The muscular coat comprised three muscular layers: (1) inner longitudinal, (2) middle oblique (circular in the distal and terminal portions), and (3) outer longitudinal. The functional significance of regional variations is discussed. The infant vas deferens showed a columnar cell type only. However, cells either with numerous lysosomes or with numerous mitochondria were occasionally found. No regional variations were observed in the infant vas.
Morphological Studies of Fiber Types of Striated Muscle Fibers of the Cremaster in the Guinea Pig
Authors: Ninomiya Jesús G. , Echeverría Olga M. , Vázquez-Nin Gerardo H.
Published: July 2008

The fine structure of the striated muscle fibers of the cremaster of the guinea pig was studied using the cholinesterase technique and light and electron microscopy. Under light microscopy, isolated single muscle fibers showed two types of nerve endings: the first one presented elliptic or oval areas having digit-like structures inside, some of the borders of which were heavily stained. These fibers had only one end-plate. The second type presented elongated clear areas with most of the density located on the borders. Several nerve endings were apparent in these fibers. By electron microscopy, the former had large and numerous sarcolemmal foldings and these characteristics were also observed in unstained fibers. In the latter, the foldings were scanty or absent. At the ultrastructural level, the fibers having only one end-plate presented a regular array of fibrils with an abundant sarcoplasmic reticulum (‘Fibrillenstruktur’ type) in contrast to the multi-innervated fiber with an irregular distribution pattern of fibrils and a scarce sarcoplasmic reticulum (‘Felderstruktur’ type). The striated muscle fiber layer of the cremaster probably contains both fast and slow fibers. The possible functional role for the slow striated muscle fibers is discussed.
Development of Arachnoid Villi and Granulations in Man
Authors: Gómez D.G. , DiBenedetto A.T. , Pavese A.M. , Firpo A. , Hershan D.B. , Potts D.G.
Published: July 2008

The superior sagittal sinus and confluens sinuum of 27 fetuses and newborns ranging from postmenstrual intervals of 26–54 weeks were studied by scanning electron microscopy and histology. 26-week specimens showed oval depressions in the final portions of tributary veins to the sinus. Histologically there were arachnoid tissue clusters within the dural wall. The walls of the depressions were more irregular by the 30th week. Arachnoid villi were apparent by the 35th week and granulations were observed after the 39th week. The granulations increased in complexity as development proceeded.
Quantitative Evaluation of the Interrelationship of Certain Endocrine Glands of Hemiechinus auritus collaris (Gray) during the Reproductive Cycle
Authors: Asawa S.C. , Mathur R.S.
Published: July 2008

The paper deals with the alterations in the size and functions of the endocrine glands in relation to the reproductive and the seasonal sexual activity of the male hedgehog. Results show that the seasonal variations in body weight, testis, adrenal and the thyroid follow the general pattern of most of the hibernating mammals. Histometric measurements of the seminiferous tubule, Leydig’s cells, thyroid follicles and the thyroid follicular epithelial cells also present an interrelationship in the seasonal cyclical activity with each other. This indicates that in Hemiechinus hormones fluctuate during the summer and winter months of the year or one can say that they are regulated seasonally thereby affecting the seasonal pattern of breeding. It has also been proposed that the cyclic activity of the endocrine glands is partly correlated with the hibernation of the animal and partly with the increased metabolic activity of the body incidental to the events of the annual cycle.
Globule Leucocytes in the Tracheal Epithelium of Rats
Authors: Vandenberghe M.P. , Baert J.
Published: July 2008

Globule leucocytes are described in the tracheal epithelium of young and adult rats. They do not appear in newborn rats up to 4 weeks. Globule leucocytes migrate through the epithelium to be found free in the tracheal lumen. They seem to be retarded a certain time in the apical part of the epithelium. The inclusions of the globule leucocytes are divided into four types. The different steps in the formation and transformation process of these inclusions are suggested. The electron-dense content of the inclusions is digested by pepsin, indicating that they contain protein. This result is not conflicting with the opinion that the globule leucocytes should contain immunoglobulins.
Surgical and Ethnic Anatomy of the Relationships between the Small Saphenous Vein and the Common Peroneal and Tibial Nerves in Adult Males
Authors: Rodrigues de Souza Romeu , Fujimura I. , Merluzzi Filho Tirço José , Ferraz de Carvalho Claudio A.
Published: July 2008

A comparative analysis of the measurements of the distances between the small saphenous vein and the common peroneal and tibial nerves at the back of the knee was performed in melanodermal and leukodermal male adults. The positions in which the vein lies more closely to the nerves are stressed and should be considered as critical in possible surgical damage to the nerves during saphenectomy.
Radioisotopic and Morphometric Evaluation of the Effects of β-Aminopropionitrile on Chick Bone Matrix Formation and Its Mineralization
Authors: Sandhu H.S. , Jande S.S.
Published: July 2008

Bones from 2-week-old chicks, fed a diet containing 0.05% β-aminopro-pionitrile (β-APN), were studied for 3H-tetracycline and β-proline incorporation at 7, 14 and 21 days of the experiment. Liquid scintillation counts showed a comparable amount of 3H-proline incorporation in the controls and experimentals. However, the incorporation of 3H-tetracycline was significantly lower in experimentals at all intervals. Fluorescent microscopy after cold tetracycline injections at similar intervals showed a comparable amount of linear bone apposition in controls and β-APN-fed chicks. The bone ash content in β-APN-fed chicks was lower at all intervals whereas the serum calcium level was similar to the controls. Microradiography showed that cortical and marrow areas, in cross sections, were not significantly different in the controls and β-APN-fed chicks. On the basis of these data it is suggested that β-APN at the dose used does not inhibit the bone matrix synthesis but inhibits its mineralization.
Cytoarchitecture of the Oculomotor Nuclear Complex and of the Trochlear Nucleus in the Marmoset (Callithrix jacchus)
Authors: Reis Francisco Prado , Machado Luiz Marcus Soares
Published: July 2008

The cytoarchitecture of the coulomotor nuclear complex (ONC) and of the trochlear nucleus (TN) was studied in the encephalon of 10 adult marmosets (Callithrix jacchus). All the encephala were fixed with Bouin, embedded in paraffin and submitted to 20-µm serial sections in the transversal, frontal and horizontal directions. The following staining methods were employed: Nissl, Kluver-Barrera, and Pal-Weigert, modified by Erhart [1951]. Morphologically we delimited four cell columns in the ONC of the marmoset, namely lateral, dorsal, anterior, and dorsal central. The lateral and dorsal central columns comparatively correspond, in man, to the somatic portion. The others to the visceral portion. The trochlear nucleus of the marmoset is compact, round in shape and can be divided in to central cellular, dorsoventral and ventrolateral groups. The neurons of both the nuclei, of the multipolar type, predominantly have a round shape but it is also possible to observe oval or triangular neurons. They have a central nucleus, the cramatine substance is not dense and is irregularly disposed. Some differences in the size of neurons can be observed among the columns of the ONC.
A Golgi-Cox Study of Tanycytes in the Hypothalamic Region of the Third Ventricle in the Wild Rat, Rattus rattus rattus(L.)
Authors: Joy K.P. , Sathyanesan A.G.
Published: July 2008

In the third ventricle of wild rat, Golgi-Cox-positive tanycytes of varied shape and size are arranged with their perikarya in the ependymal layer and basal processes extending into the core of the subependyma. The basal processes may be smooth and slender, or barbed and branching, and often take circuitous and overlapping courses. In some, the apical part of the perikaryon projects into the ventricle. In the arcuate region, groups of closely arranged tanycytes whose long basal processes end on the arcuate neurons and the portal vessels in the tubero-infundibular sulci are noticed. The tanycytic processes of the median eminence terminate on the portal vessels in the palisade layer. Some tanycytic processes of the mammillary recess even extend up to the ventral surface of the brain and have disc-like terminations.
The Types of Proliferating Glioblasts in the Immature Mouse Neocortex and Dentate Gyrus as Revealed by Electron Microscopic Autoradiography
Authors: Reznikov K.Y. , Bascó E. , Csillag A. , Hajós F.
Published: July 2008

Proliferating glial elements of 3 to 12-day-old mouse parietal cortex and dentate gyrus were investigated by the electron microscopic autoradiography of 3H-thymidine. The presence in these regions of three types of proliferating glial precursors was verified and related to astrocyte development. Comparing the two areas studied it was concluded that postnatal glial proliferation is independent from neurogenesis and that astroglia is capable of proliferation even in advanced stages of differentiation.
Staining of Collagen and Elastin in Tissue Slices with the Methyl-Benzothiazol-2-On-Hydrazone Reagent
Authors: Horvath A. , Cabrera R. , Vial E.
Published: July 2008

Collagen and elastic fibres were stained in cryostatic slices of various tissues with the MBTH reaction, specific for aldehyde groups. Depending on the source, collagen and elastin gave different colours, easy to distinguish. It appears that this simple technique could be useful not only to visualize cross-linking in vivo of these fibres but also to explore their pathological alterations.
Progressing Alterations in Transient Ischemia of Skeletal Muscles: An Ultrastructural Study
Authors: Ludatscher R.M. , Hashmonai M. , Monies-Chass I. , Schramek A.
Published: July 2008

Ultrastructural muscle changes resulting from temporary anoxia and their evolution were studied in dogs. Ischaemia of the hind limb was produced by subcutaneous ligation of all muscles of the thigh and clamping of the femoral artery. Revascularization was obtained by declamping and removal of the muscle ligature. The period of ischaemia ranged from 4½ to 7 h, the latter being the upper limit allowing functional recovery after revascularization. 6–7 h of ischaemia revealed focal degenerative changes of varied intensity. These consisted of enlarged mitochondria with ruptured criptae, small pads of glycogen granules and accumulation of lipid vacuoles. The tubules of sarcoplasmic reticulum contained dense, fine-granular material. Focal myofibrillar distruction and disrupture of the Z line were encountered in half of the cases. The myofibrillar damage was more severe 9 days after revascularization of the muscles. The functional recovery of the ischaemic limbs in the present study may be due to the focal nature of these changes.
Fine Structure of the Second Kind of Thyroid Follicles in Mature Guinea Pigs
Authors: Juhl Marianne
Published: July 2008

The second kind of follicle (S-follicle) is in mature guinea pigs a morphologically heterogeneous structure located in the central part of the upper two-thirds of the thyroid lobe. An S-follicle may appropriately be divided in an upper, a middle, and a lower part. This paper deals with the ultrastructure of the upper tubular part and the middle part. The latter is further subdivided in an irregular follicle and a distended follicle. In the tubular part a single cell type, termed the S-follicle cell, is dominating. This cell is most often arranged in a single layer and is characterized by an indented nucleus and by presence of pinocytose vesicles and hemidesmosomes along the basal cytoplasm membrane. In addition, C cells are frequently found. In the irregular follicle five different cell types are noticed: S-follicle cells, dark fibrillar cells, granulated cells, ciliated cells, and C cells. The S-follicle cells display an ultrastructure similar to those in the tubular part but are frequently arranged in two or more layers. Both the tubular part and the irregular follicle are surrounded by connective tissue. In the distended follicle, however, contact areas to thyroid follicles are found. Adjacent to these contact areas, cells with an ultrastructure similar to that of thyroid follicle cells proper are encountered in the wall of the S-follicle. This observation suggests that the distended part of an S-follicle in mature guinea pigs might be regarded as a kind of mixed follicle. The origin of thyroid follicle cells proper in the wall of the S-follicle is briefly discussed.
Transplacental Effects of 1,25-Dihydroxycholecaiciferol and of 24,25-Dihydroxycholecalciferol on the Limb Skeleton of Fetuses and Offspring of Rats
Authors: Zusman I , Hirsh B.E. , Edelstein S. , Ornoy A.
Published: July 2008

The transplacental effects of 1,25(OH)2D3 and of 24,25(OH)2D3 on bone formation in rat fetuses and pups have been investigated. Pregnant rats treated with 1,25(OH)2D3 or with 1,25(OH2D3 and 24,25(OH)2D3 showed hypercalcemia, while those treated with 24,25(OH)2D3 did not. Fetal weight was markedly reduced by treatment with 1,25(OH)2D3 and not with 24,25(OH)2D3 or with a combination of both metabolites. Microscopical examination of fetal long bones showed after treatment with 1,25(OH)2D3 a marked reduction in diaphysial length. Diaphyseal trabeculae were thin and disorganized. The epiphysis had a thinner layer of hypertrophic and calcified cartilage. The numbers of osteoclasts in the diaphysis and metaphysis were the same as in controls. Treatment with 24,25(OH)2D3 did not affect fetal bone length; many bone trabeculae were found in the diaphyseal cavity leaving small bone marrow spaces; the number of osteoclasts in the metaphysis and in the diaphysis was increased. All changes in the skeleton disappeared during the first week after birth. It can be suggested that high doses of 1,25(OH)2D3 inhibit bone formation and maturation of cartilage. The addition of 24,25(OH)2D3 to 1,25(OH)2D3 seemed to reduce the toxic effects of the latter on the fetal skeleton. These results point to a definite difference between the action of high doses of 1,25(OH)2D3 and 24,25(OH)2D3 on fetal bone.
Compensation Mechanisms for Experimental Reduction of the Functional Capacity in the Guinea Pig Placenta
Authors: van der Heijden F.L.
Published: July 2008

After experimental reduction of its functional capacity, the placenta of the guinea pig has been studied microscopically for changes in the maternal and fetal vascularization pattern which could be interpreted as a compensation for this reduction. The functional capacity has been reduced in four ways. In the experimental groups the volume density of fetal capillaries in the labyrinthine part of the placenta was increased significantly compared with untreated controls. The surface density of these vessels, however, remained the same as in the control placentas. The volume density and surface density of the maternal lacunae did not change significantly. The conclusion is that after experimental reduction of its functional capacity the only structural modification in the guinea pig placenta involving the maternal and fetal vascularization, which can be interpreted as a compensation mechanism, is a widening of the fetal capillaries in the labyrinth.
Compensation Mechanisms for Experimental Reduction of the Functional Capacity in the Guinea Pig Placenta
Authors: van der Heijden F.L.
Published: July 2008

The functional capacity of the placenta of the guinea pig has been reduced in four different ways. It has been investigated whether changes in the trophoblast of the labyrinthine part of the placenta occurred which could be interpreted as a compensation mechanism for the reduction of the capacity. No significant decrease of the thickness of the maternofetal barrier could be measured nor did enlargement by microvilli of the apical and basal surface of the syncytium change significantly. Activities of the enzymes glucose-6-phosphate dehydrogenase, lactate dehydrogenase, glucose-6-phosphatase and adenosine triphosphatase showed a great variation, but no differences in activities could be demonstrated. Further, the number of cytotrophoblastic cells was widely spread and no significant difference could be observed, although sometimes large and apparently newly formed parts of lobulus were observed.
An Analysis of Satellite Cell Content in the Semimembranosus Muscle of Japanese Quail (Coturnix coturnix japonica) Selected for Rapid Growth
Authors: Campion Dennis R. , Marks Henry L. , Richardson Leslie R.
Published: July 2008

Transverse sections of the semimembranosus muscle of a control (C) line of Japanese quail and of a line (P) selected for high body weight at 4 weeks of age were observed for nuclear content. The two lines were sampled at 4 days posthatching and at 4 weeks of age. The relative number of satellite cells decreased from 4 days to 4 weeks of age. The total number of satellite cells, however, appeared to increase as muscle length increased; this relation was not influenced by line effects. It was concluded that the greater number of nuclei in the longer fibers of P-line quail was principally the consequence of a greater mitotic rate in the satellite cells of this line compared to the C-line quail.
Re-Evaluation of the Colic Irrigation from the Inferior Mesenteric Artery
Authors: Vandamme J.P.J. , Bonte J. , van der Schueren † G.
Published: July 2008

156 abdominal preparations were explored by arteriography, corrosion and dissection. The arteria mesenterica inferior (AMI) ends by bifurcating into the two arteriae rectales superiores. The key to the interpretation of the AMI is the recognition of an arteria colosigmoidea that gives off one or more rami sigmoidei. In the presence of an arteria or ramus colic, sin. access, usually from the superior mesenteric artery, the left colic artery is absent, atrophic or displaced. The sigmoid branches (usually three) arise from the colosigmoid, the left colic or the distal portion of the AMI. Usually, the last sigmoid artery gives branch to the rectosigmoid colon. The rectosigmoid artery arises from the AMI between arteria sigmoidea ima and the terminal bifurcation of the former. It may be replaced by the descending branch of the a. sigmoidea ima. They irrigate an extensive part of the anterior wall of the bowel.
Histology and Fine Structure of the Hamster Retinal Pigment Epithelium
Authors: Buyukmihci Ned , Goehring-Harmon Faye
Published: July 2008

The retinal pigment epithelium of normal adult golden Syrian hamsters was examined by light and electron microscopy, using conventional and enzyme histochemical techniques. Hamster retinal pigment epithelium was composed of a single layer of cuboidal cells that had marked infolding of the basal cell wall and numerous microvillous processes extending from the apical surface. Melanin content varied within each specimen and there appeared to be incomplete or aberrant development of many melanin granules. Many incompletely melanized granules showed acid phosphatase activity. There were the usual cell organelles, including mitochondria, smooth and rough-surfaced endoplasmic reticulum, ribosomes, and Golgi complexes. Large phagosomes increased in number in the morning hours. Autophagic vacuoles and small lipid droplets were commonly seen. Occasional basal bodies, cilia, and root filaments were found. In two specimens, a curious intranuclear para-crystalline structure was observed.
Sutural Growth
Authors: Oudhof H.A.J.
Published: July 2008

As the skull develops, the tissue of the coronal and sagittal sutures (serrated sutures) assumes a specific structure which in part is practically identical to that of a gomphosis joint and may therefore be regarded as a ‘multigomphosis’. The nature of this structure justifies the assumption that it has to resist mechanical forces exerted on the suture. The results of transplantation experiments with portions of sutures suggest that the sutural structures are determined hereditarily, but that environmental factors are required for these qualities to manifest themselves.
Scanning and Transmission Electron Microscopy of the Normal Rabbit Aortic Endothelium after Controlled Perfusion Fixation
Authors: Garbarsch Charly , Tranum-Jensen Jørgen , van Deurs B.
Published: July 2008

Light microscopy, scanning electron microscopy, and transmission electron microscopy were employed on the anterior wall of the rabbit thoracic aorta with the particular purpose to study endothelial marginal flaps and the structure of stomata under physiological conditions at 100 mm Hg. Intra-aortic pressure monitoring was performed during the whole period of perfusion (2 h), restricting pressure variations to a maximum of ± 5 mm Hg in order to preserve endothelial architecture. We found the endothelial surface uniformly smooth. Marginal flaps of the endothelial cells were mutually overlapping, often forming multiple layers. Underlying flaps might protrude to the lumen between neighbouring flaps as flat mushrooms. Flaps of adjacent cells might diverge for short distances to decover an underlying endothelial cell. Downstream flaps of the cells might be overlapped at their base by flaps of adjacent cells, the extremity of the flap thus appearing as a disc separated from the cell. The small discs and troughs thus formed are considered equivalent to the so-called stomata.
A Study of Two Enteroendocrine Cells in the Duodenum of the Gerbil-Meriones unguiculatus
Authors: Kapur Shakti P.
Published: July 2008

Gastrin-secreting G cells and enterochromaffin cells have been examined in the duodenum of the gerbil-Meriones unguiculatus. G cells examined by immunoperoxidase and immunofluorescence methods were seen primarily located in the mucosa lining the villi and rarely in the glands of Lieberkühn. They were flask-shaped cells that extended from the basal lamina to the mucosal surface. Immunoreactive gastrin was localized all over in the cytoplasm but was especially concentrated in the juxtanuclear and subnuclear regions. Enterochromaffin cells were identified by a serotonin-specific formaldehyde-induced fluorescence method. These cells were also primarily located in the duodenal villi, were flask-shaped and revealed an intense yellow fluorescence that was especially concentrated in the subnuclear cytoplasm. At the ultrastructural level the enterochromaffin cells showed numerous pleomorphic electron-dense secretory granules especially located in the subnuclear cytoplasm. Microfilament bundles were often observed, especially in the perinuclear region.
Morphokinetik der TSH-stimulierten Meerschweinchenschilddrüse in vitro
Authors: Luttermann M. , Böcker W.
Published: July 2008

Guinea pig thyroid tissue was incubated in a tissue culture system in the presence of various TSH concentrations and for various time periods. The morphokinetic response was examined with the electron microscope. The qualitatively finer aspects of the TSH-caused sequence of events are described and compared with in vivo results. After in vitro stimulation the general changes of cell membranes and of the cytocavitary network are very similar to those in vivo. On the other hand, there are differences with regard to intensity and duration of the structural response to TSH and additionally degenerative changes of organelles are found which might be explained by incubational factors. The role of the mitochondria as a source of energy is demonstrated by typical qualitative and quantitative alterations. An interesting finding is the degradation of mitochondria within colloid droplets, a mechanism which is suggested to represent a modified autophagy. Intracellular follicles are occasionally found during in vitro experiments. The formal genesis of this structure and its possible role is discussed. The present study indicates that this incubation model provides a useful tool for further analyses of thyroid disorders.
Stimulating Effect of the Low Dose Laser – A New Hypothesis
Authors: Yew David T. , Ling Wong S.L. , Chan Yau-wa
Published: July 2008

Increase in the amount of secretary material (interreceptor matrix) surrounding the visual cells was observed after laser treatment. At the same time, an increase in labelled uridine uptake by the pigment epithelium was detected. The increase uptake was highest 4 h after laser treatment.
Adrenergic Innervation of the Left Side of the Guinea Pig Heart
Authors: Sullivan James M.
Published: July 2008

Histological, histochemical fluorescence, and electron microscopic techniques have been utilized to demonstrate the specific distribution of the noradrenergic sympathetic postganglionic fibers to the guinea pig left atrium and ventricle. The majority of these nerves entered the base of the heart. Paravascular bundles of unmyelinated sympathetic postganglionic fibers traversed the left atrioventricular sulcus. From these paravascular plexuses axons accompanied the arteries via periarterial plexuses to the deeper layers of the heart wall. The vascular tree was extremely complex. In the left atrium a relatively abundant noradrenergic innervation was seen within the interstitial connective tissue surrounding the cardiac muscle. In the left ventricle, most of the noradrenergic innervation was located in the tunica adventitia of all the major coronary arterial branches before they entered the cardiac muscle. These larger branches of the coronary arteries were predominantly innervated by the sympathetic postganglionic fibers. Apparently it is from these perivascular nerve plexuses that the left ventricular muscle receives the majority of its noradrenergic innervation.
Fine Structure of the Vomeronasal Neuroepithelium of Bats: A Comparative Study
Authors: Bhatnagar Kunwar P. , Matulionis Daniel H. , Breipohl W.
Published: July 2008

The vomeronasal neuroepithelium of the vampire bat, Desmodus rotundus, and the frugivorous bats, Carollia perspicillata and Artibeus jamaicensis, was examined at the light-microscopic and ultrastructural levels. The neuroepithelium of these species is basically similar in morphology to that of other mammals. However, hitherto unknown differences were noted in regard to the configuration of the apical poles of cells, in the occurrence of solitary cilia, dislocated sensory cells, brush cells, cell contacts and the occurrence and fine structure of basal cells. The morphology of the vomeronasal neuroepithelium of all three species is discussed from a comparative point of view in regard to chemoreception.
A Light and Electron Microscopic Study of the Human Ovarian Ligament
Authors: Curry, Jr. Thomas E. , Hodson Charles A. , Capps Marilyn L. , Mozley P.D. , Jones D.E.D. , Burden Hubert W.
Published: July 2008

The structure of the human ovarian ligament was studied with light and electron microscopy, with emphasis on neural components. The ligament is primarily composed of smooth muscle arranged in an outer oblique and an inner longitudinal layer. The smooth muscle cells are connected by two types of intercellular junctional complexes, close contacts and intermediate junctions. The intercellular junctions may serve to coordinate smooth muscle activity and synchronize contractions of the ligament. Nerves are abundant and accompany the vascular supply. Specialized encapsulated neural structures previously reported were not observed. Acetylcholinesterase-positive nerves are more numerous than adrenergic nerves. Both types of nerves are associated with vascular smooth muscle. We conclude that these nerves either traverse the ligament or terminate in the ligament and are vasomotor.
Fine Structure of the Extraganglionic Nerve Plexuses of the Guinea-Pig Stomach
Authors: Hoyes A.D. , Barber P.
Published: July 2008

The fine structure of the perivascular and the other extraganglionic nerve plexuses in the muscularis externa and the mucosa of the guinea-pig stomach was studied in specimens fixed by perfusion and in specimens fixed by immersion after in vitro incubation in 5-hydroxydopamine. In each of the plexuses, over 50% of the nerves contained ten axons or less; terminal profiles were also much more numerous in sections of nerves of this size than in sections of the larger nerves. Five types of axon terminal were identified in the nerves. Terminals containing mainly large dense-cored vesicles were few, but were more numerous in the perivascular than in the other plexuses. Terminals containing small clear vesicles and large dense-cored vesicles approximately 140 nm in diameter were also few and were confined to the plexuses in the muscularis externa. The remaining types of terminal could be clearly differentiated only in specimens incubated in 5-hydroxydopamine. Terminals containing small clear vesicles were present in large numbers in the plexuses in the muscularis externa and the mucosa. Terminals containing small dense-cored vesicles constituted all but a small proportion of those seen in the perivascular plexuses. They were also seen in small numbers in each of the other plexuses. The remaing type of terminal contained small vesicles which were larger than in the other types and which contained halos of electron-dense material. Such terminals were present only in the plexuses in the muscularis externa and were concentrated in nerves located close to the myenteric plexus.
Patterns of Superficial Veins of the Cubital Fossa in Nigerian Subjects
Authors: Singh Jay Datta
Published: July 2008

Patterns of superficial veins of the cubital fossa were studied in 300 persons in Nigeria. Five types were observed in this study. The commonest pattern found in Nigerians was the median cubital vein arising from the cephalic vein a little below the level of the elbow (62% in males and 49% in females). To some extent this incidence is comparable with the findings in Americans (70%) and Britishers (53%). However, there is a clear contrast when compared with Japanese (84%) and Indians (16%). The next commonest pattern in Nigerians was the median vein of the forearm dividing into two and joining the basilic and cephalic veins (24–30%). This pattern was also comparable with Americans and Britishers but is in clear contrast to the findings in Indians and Japanese. The incidence of the other patterns was very low in this as well as in all other reports.
An Ultrastructural and Cytochemical Study of Enteroendocrine Cells of the Pyloric Antrum in the Gerbil, Meriones unguiculatus
Authors: Kapur Shakti P.
Published: July 2008

Enteroendocrine cells of the gastric antrum have been examined in the gerbil, Meriones unguiculatus. Gastrin-secreting G cells were identified by immunocytochemical methods and by transmission electron microscopy. They were present in the lower and middle third of the pyloric antral glands. G cells were polyhedral in shape and often extended to the gland lumen where they presented a microvillous and pinocytotic surface. These cells were characterized by numerous electron-dense and immunoreactive secretory granules. Enterochromaffin cells were identified by a serotonin-specific formaldehyde-induced fluorescence method, and by electron microscopy which revealed pleomorphic secretory granules of varying electron densities. These cells also had luminal projections and had a shape and distribution essentially similar to those of the G cells. A third endocrine cell type was identified as Dl cell in the pyloric glands. This cell type was recognized by the presence of numerous secretory granules having an electron-dense core and a clear peripheral space, as also by the presence of microfilament bundles, especially in the peri-nuclear region. The functional correlates of these morphological observations are discussed with reference to their secretory product and the manner of its release, especially by the G cells.
Kompensations- und Stabilisationsbewegungen der Fibula
Authors: Reimann Reinhold , Anderhuber Friedrich , Ebner Inge
Published: July 2008

There are two reasons why the fibula shows longitudinal motions. During dorsiflexion the push of the wedge-shaped trochlea tali causes an upward fibular motion; on the other hand, during weight bearing the contraction of the leg muscles effects a downward fibular motion. The specific level of the fibula results from these two correlating forces. While the upward fibular migration is a passive compensative movement, the downward fibular migration is an active stabilizing movement.
Investigations of Alkaline Phosphatase Ca+2-ATPase and Na+, K+-ATPase during Beta-APN-Induced Initial Bone Mineralization Inhibition
Authors: Sandhu H.S. , Jande S.S.
Published: July 2008

Tibias of 6-day-old white Leghorn chick embryos treated with β-aminopro-pionitrile (β-APN; 0.1 mg/egg/day) for 4 days and injected with 3H-proline or β-tetracycline on the 11th day were analyzed for incorporation of 3H-proline and 3H-tetracycline. The incorporation of 3H-proline was comparable in the controls and β-APN-treated embryos. However, the incorporation of 3H-tetracycline was significantly lower in β-APN-treated embryos. The bone ash contents were also lower in the latter group. Alkaline phosphatase and Ca+2-ATPase were found to be significantly lower in β-APN-treated embryonic bones. There was, however, no difference in the activity of Na+, K+-ATPase. The histochemical examination showed the alkaline phosphatase to be present on osteoblasts and matrix vesicle plasma membranes at the periosteal surface. The chick embryonic liver tissue showed no significant differences in the activities of any of the above enzymes. The results suggest that β-APN-induced inhibition of the bone mineralization may be due to the bone-specific inhibition of alkaline phosphatase and Ca+2-ATPase.
2-Mercaptopropionylglycine Protection against Growth-Inhibiting Effects in in utero Irradiated Mice
Authors: Dev P.K. , Pareek B.P. , Gupta S.M. , Goyal P.K. , Mehta G.
Published: July 2008

Pregnant Swiss albino mice at different fetal growth periods were exposed to 150 R gamma rays in the presence or absence of 2-mercaptopropionylglycine (MPG), a SH radioprotector. The weights of litters born to these mothers were recorded at different post-partum intervals. There was an initial weight loss at 1 week after birth followed by a second weight loss after 4 weeks in the unprotected control males, whereas females showed continuous gains in weight from initial loss at 1 week. In the MPG-treated groups, the pattern of weight changes remained the same, but the loss was significantly less than in the controls and the second weight loss in the case of males was not obvious.
Elektronenmikroskopische Untersuchungen über die postnatale Entwicklung der Leydig-Zellen des Menschen
Authors: Seguchi Harumichi , Hadžiselimović Faruk
Published: July 2008

The development of Leydig cells from the 1st to the 14th year was electron microscopically investigated in specimens of testicles. Leydig cells and their precursor were found in the interstitium. The precursors of the Leydig cells were usually spindle-shaped and contained few organelles and filamentous structures. Leydig cells were usually found in groups. The nucleus was round and eccentric. The most striking feature of Leydig cells was the abundance of smooth endoplasmic reticulum. It was tubular and vacuolar in appearance. Mitochondria possessed cristae of the tubular type and contained occasionally intramitochondrial granules. Glycogen granules and lipid droplets were noted in the cytoplasm. No Reinke crystalloids were found throughout this period. Leydig cells arose from mesenchymal cells via their precursors. Phases of regression of Leydig cells were observed twice, in the 2nd and 3rd years, and from the 9th to the 11 th year. In these periods the above-mentioned Leydig cells were seldom observed and only degenerating cells were noted. After the 13th year the Leydig cells increased in size and in number.
Light Microscopic Morphometry of the Lung of 19 Avian Species
Authors: Maina J.N. , Abdalla M.A. , King A.S.
Published: July 2008

The lungs of 107 birds of 19 different species from seven orders were fixed in situ. The mean volumes of both fixed lungs together ranged from 0.15 to 95.31 cm3. Histological sections of one lung from each bird were analyzed by point counting with a Zeiss integrating eyepiece to determine the volume densities and thence the absolute volumes of the main functional components of the lung. The mean volume density of the exchange tissue was highest in the 11 passeriform species (53.5%) and lowest in the 2 charadriiform species (34.6%); that for all of the 8 non-passeriform species was 42.6%. The possible significance of these variations in relation to the differing oxygen requirements of these groups of birds is discussed. The parabronchi showed minor variations in the degree of development of the interparabronchial septa, atria, interatrial septa, and atrial muscles. The diameter of the parabronchi (including the mantle of exchange tissue) ranged from about 0.34 mm in the passeriform species to about 0.63 mm in Anser anser; the lumen of the parabronchus accounted for about half of this diameter. Body weight and lung volume were strongly correlated (0.995); the allometric function relating lung volume to body weight was 29.5 w⁰·988.
Association Projections from the Secondary Somatosensory Cortex in the Cat
Authors: Yamaguchi Kyohei , Massopust Leo C. , Young Paul A. , Horenstein Simon
Published: July 2008

The autoradiographic study of the association fiber connections of the secondary somatosensory area in the cat confirmed all the connections that were described by Yamaguchi in 1980, using the Fink-Heimer method. The direct projection to the ‘perirhinal cortex’, located in the lateral wall of the posterior rhinal sulcus, was ascertained. The projections to the insular cortex, the medial part of area 5, the suprasylvian fringe and area 3a, were confirmed. The columnar configurations in the termination of the association fiber in cats were, for the first time, provided by the use of the axoplasmic flow study.