bluuebunny/crossref_metadata_2025 huggingface dataset:
Clomiphene Citrate Alters Surface Ultrastructure of Uterine Luminal Epithelial Cells
Authors: Hosie M.J. , Murphy C.R.
Published: July 2008

Scanning electron microscopy was used to evaluate the uterine luminal epithelium from ovariectomized rats treated with a single minimal physiological dose of clompiphene citrate, oestradiol-17β or progesterone. It was found that clomiphene treatment produced some ultrastructural surface features which were similar to those seen with both oestrogen and progesterone treatment, but in addition it produced features unique to clomiphene treatment.
Organic Structures of the Hypercalcified Peritubular Matrix in Horse Dentine
Authors: Kodaka T. , Hirayama A. , Abe M. , Miake K.
Published: July 2008

EDTA-insoluble organic structures of the hypercalcified peritubular matrix (PM) in horse dentine were observed by scanning electron microscopy. The PM was enveloped in double cylindrical structures composed of fibrillar sheaths in the inner and outer peripheries. Between the outer fibrillar sheath and intrinsic fibrils of the intertubular matrix, a calcified cementing membrane existed. Within the PM, warped cone-shaped structures of fibrillar sheaths, overlapping at intervals of 4-6 µm and semiconcentrically surrounding the dentinal tubule, extended from the inner fibrillar towards the outer fibrillar sheath. The cone-shaped fibrillar sheaths following the inner and outer fibrillar sheaths were identified as the incremental lines of the PM. Most of these fibrils may be collagen although it could not be confirmed, whereas non-collagenous organic materials in the lateral branches of the dentinal tubule are radially arranged in the PM. These EDTA-insoluble structures were three-dimensionally illustrated using an image-analysing system.
Clomiphene Citrate Alters Vaginal Surface Morphology in Cycling Rats
Authors: Terry V. , Murphy Ch.R. , Shorey C.D.
Published: July 2008

Cycling virgin female rats were treated with clomiphene citrate (CC) during dioestrus of the reproductive cycle. Animals were sacrificed 2 days after the initial injection and their vaginal tissue was examined by scanning electron microscopy. Animals treated with one dose of CC had an epithelium consistent with a prolonged dioestrus. Treatment with CC for 2 days induced changes in the epithelium that had no resemblance to any normal hormonally controlled event in the vagina. It was found that CC had effects consistent with progesterone alone as well as effects unique to this superovulatory drug.
Abdominal Part Artery of Axillary Artery: Proposed Term for the Artery Supplying the Abdominal Part of the Musculus pectoralis major
Authors: Sato Y. , Takafuji T.
Published: July 2008

In 1976, the authors reported that the abdominal part artery (Pab) supplying the abdominal part of the pectoralis major muscle usually originates from the axillary artery (Ax). The findings in the present study show that the type of origin of this artery most frequently encountered is type 2-a (44.0%) in which the Pab, as an independent branch (type a), branches out of the second part of the Ax (type 2). The second and third most frequently encountered types are type 2-b (17.0%), where the Pab has a common trunk with the thoracoacromial artery, and type 2-c (10.0%), where it has a common trunk with the lateral thoracic artery. By classification according to the supplying areas, 67% was type I-B, supplying the lower part of the pectoralis minor muscle and the abdominal part of the muscle. In 5% the branch as type I-A courses down to the sternocostal part. In most cases (types A and B in 91%), this artery originates from the Ax proximal to the ansa mediana of the brachial plexus; however, in 4% providing the superficial brachial artery, the Pab branches out from the superficial brachial artery. Based on those findings, the authors would propose that the artery be named the arteria partis abdominalis or Pab.
Biogenesis of the Ciliary Roots: Participation of the Dictyosomes of Golgi’s Complex
Authors: Santander Gonzalez , Cuadrado Martinez , Martínez González-Santander , Lobo Toledo , Alonso Martínez
Published: July 2008

In this study, the hypothesis of a possible biogenesis of the ciliary roots is suggested, after observing the cilia neurons under the electron microscope, which were found as an exception in the periaqueductal nucleus of the mesencephalon in the domestic cat, conserving the potential to differentiate the cilia, basal bodies and ciliary roots. The dictyosomes of Golgi’s complex and Golgi’s vesicles participated in this biogenesis. Vesicles of approximately 71.6 nm in diameter had become separated from the periphery of the flattened discoid cisterns of the dictyosome and were aligned normally, in tangential contact with each other, forming rows of vesicles or ‘ringed chains’, whose points of contact formed the beginning of the ‘periodic striation’ of a thin ciliary root. Later, the lateral walls of the vesicles and the molecules of the intracisternal proteins gave rise to the interperiodic microfilaments, when the carrier proteins were transformed into structural proteins of the ciliary roots. The parallel apposition of several ringed chains or thin ciliary roots, with their rings joined at the same level (or transversal striations), gave rise to thicker striated roots. This hypothesis of an ultrastructural biogenesis of the striated ciliary roots involves the following six stages: stage I = separation of Golgi’s vesicles from the periphery of the flattened disk of dictyosomes near the basal body, with a diameter of over 71.6 nm; stage II = reinforcement of the membrane of the vesicles at the two opposite polar ends of its larger diameter; stage III = alignment of vesicles to form ringed chains, due to the tangential contact between their reinforced points; initiation of the 71.6-nm striation period, roots ringed linearly; stage IV = formation of joining microfilaments between periods (69.2 nm) with the lateral walls of the vesicles and the molecules of the proteins in their content; stage V = lengthening of the thin ciliary roots due to the coupling of new Golgi’s vesicles at their ends so that their length increases as a result of the addition of terminal vesicles; stage VI = increase in thickness of the thin ciliary roots, due to the parallel apposition of several ringed chains or thin ringed ciliary roots, at the point where their transversal striation points coincide.
Ultrastructural Development of Chorioallantoic Placenta in the Indian Miniopterus Bat, Miniopterus schreibersii fuliginosus (Hodgson)
Authors: Bhiwgade D.A. , Singh A.B. , Manekar A.P. , Menon S.N.
Published: July 2008

The chorioallantoic placental interhemal membrane of Miniopterus schreibersii fuliginosus has been described electron-microscopically. Morphologically thereare three main types of placentae which develop in chronological sequence. They are (1) primary placenta, (2) secondary placenta and (3) tertiary placenta. In neural groove and limb-bud embryos the primary placenta consists of the following elements which separate the maternal and fetal circulations: (1) a continuous ectoplasmic layer, (2) intrasyncytial lamina, (3) syncytiotrophoblast, (4) cytotrophoblast, (5) basal lamina, (6) mesenchyme and (7) fetal endothelium. The primary placenta degenerates until term when it consists of a thin syncytiotrophoblastic layer resting on basal lamina. Mesenchyme does not show the presence of fetal capillaries. The secondary placenta is formed in early limb-bud embryos. The electron microscope has revealed that the placenta is of the endotheliomonochorial type and (1) consists of a well-developed maternal endothelium, (2) the trophoblast surrounding the maternal blood tubule is cellu lar, not syncytial as previously thought and the apical plasma membrane of these trophoblastic cells is in direct contact with the discontinuous interstitial membrane, (3) basal lamina, (4) mesenchyme and (5) fetal endothelium. Tertiary placenta at full term stage is of the hemodichorial type having the following elements: (1) thin ectoplasmic layer, (2) a thick intrasyncytial lamina, (3) syncytiotrophoblast, (4) cytotrophoblast, (5) basal lamina, (6) mesenchyme and (7) fetal endothelium. The definitive chorioallantoic placental barrier in this bat thus differs from the organization earlier proposed by Chari and Gopalakrishna [Proc. Indian Acad. Sci. 93: 463-483, 1984] on the basis of light-microscopic observations: (1) the absence of maternal endothelium in the primary placenta from the neural groove and early limb-bud embryos, (2) the existence of only cellular trophoblast in the secondary placenta throughout the gestation and (3) the presence of well-developed hemodichorial tertiary placenta is the unique feature of the interhemal membrane in higher Chiroptera.
Fibroblast Growth Factor: Effects on Osteogenesis and Chondrogenesis in the Chick Embryo
Authors: Frenkel S.R. , Herskovits M.S. , Singh I.J.
Published: July 2008

In vivo effects of fibroblast growth factor (FGF) on osteogenesis were evaluated in the chick embryo. Autoradiographic studies of Η-proline labeling over bone matrix indicated that 24 h after treatment on day 11, FGF stimulated osteogenic cell proliferation, while inhibiting the production of bone matrix collagen. However, 4 days after multiple doses of FGF, the large pool of newly formed osteogenic and chondrogenic cells expressed their function with the increased formation of matrix. The data provide in vivo evidence of the effects of exogenous FGF on osteogenesis and also point to a possible role for FGF both in embryonic osteogenesis and in fracture repair.
Quantification and Distribution of Troponin-T in Cultures of Chick Embryo Myocardiocytes
Authors: Vélez G. , Aránega A.E. , Muros M.A. , González F.J. , Prados-Salazar J.C. , Alvarez L. , Aránega A.
Published: July 2008

We analyzed the distribution and labeling patterns of troponin-T, a protein involved in the regulation of striated muscle contraction, in myocardiocytes obtained from chick embryos in Hamburger and Hamilton’s stage 25 and 39, and cultured for 8 days. Troponin-T expression was examined with indirect immunofluorescence, densitometry, fluorescence-activated cell sorting, electrophoresis and immunoblotting. The patterns of expression of troponin-T were compared with those of actin to determine possible correlations in different stages of chick embryo development and culture. Our findings show that in both stages of embryonic development, the cellular accumulation of troponin-T changed after 8 days of culture. Our results revealed a quantitative modification with time: after 4 days of culture there was a significant increase in this protein, followed by a slight additional increase after 8 days of culture. Flow cytometry findings confirmed these trends over time, showing a significant increase in positive cells after 4 days, followed by a smaller rise after 8 days of culture. In comparison with actin, this pattern was similar only in cells from Hamburger and Hamilton’s stage 25 embryos.
Developmental Changes in the Distribution of Cecal Lectin-Binding Sites of Balb-c Mice
Authors: Doehm S. , Breipohl W. , Lierse W. , Romaniuk K. , Young W.
Published: July 2008

The existence of lectin-binding sites was investigated in the cecum of Balb-c mice at seven developmental stages ranging from 18 days post conception (p.c.) to 8 weeks after birth. Nine horseradish-peroxidase-conjugated lectins (concanavalin A, Triticum vulgaris, Dolichus biflorus, Helix pomatia, Arachis hypogaea, Glycine maximus, Lotus tetragonolobus, Ulex europaeus, Limulus polyphemus) were applied to 5- to 7-µm thin paraffin sections of Bouin-fixed tissue. After DAB staining the sections were evaluated by light microscopy. It was shown that each lectin exhibits a unique developmental pattern. The adult binding patterns were established at the age of 3-4 weeks with only minor changes occurring thereafter. Considerable differences in binding patterns occurred not only between lectins of different groups but also between lectins with the same nominal monosaccharide specificity.
Metamorphic Changes in the Vagal Innervation to the Alimentary Tract in the Green Frog, Rana clamitans(Ranidae)
Authors: Brown C.A. , Wassersug R.J. , Naitoh T.
Published: July 2008

The alimentary tract of typical anurans shortens extensively at metamorphosis when the microphagous tadpole transforms into a macrophagous frog. We used methylene blue vital stain and Sihler stain, in conjunction with microdissection to map the distribution of the gastric branch of the vagus nerve in green frogs (Rana clamitans) before and after metamorphosis. After metamorphosis, termnal divisions of the gastric branch can be observed on the tunica musculosa extending as far as the pylorus. In the tadpole, the gastric branch ends abruptly on the esophagus. The premetamorphic pattern of innervation is consistent with the absence of digestive activity in the foregut before metamorphosis. Preliminary experiments, involving stimulation of the gastric branch of the vagus in the tadpoles, confirm the anatomical observation of the absence of vagal innervation before metamorphosis.
Effects of Hypergravity Environment on the Parathyroid Gland of the Norepinephrine-Treated Golden Hamster: A Stereological Study
Authors: Shoumura S. , Emura S. , Utsumi M. , Chen H. , Hayakawa D. , Yamahira T. , Terasawa K. , Tamada A. , Arakawa M. , Isono H.
Published: July 2008

Effects of 5-gravity environment on the ultrastructure of the parathyroid glands of norepinephrine-treated golden hamsters were studied. In the centrifuged animals treated with norepinephrine, the volume density occupied by the Golgi complexes associated with numerous prosecretory granules was significantly increased compared with that of the control, centrifuged and norepinephrine-treated animals, as well as the volume density occupied by the cisternae of the granular endoplasmic reticulum compared with that of the control and centrifuged animals. In addition, in the centrifuged animals treated with norepinephrine, numerous secretory granules were situated close to the plasma membrane. It is suggested that the synthesis and release of secretory granules may be markedly stimulated in the parathyroid glands of the norepinephrine-treated golden hamsters subjected to a hypergravity environment.
Changes in the Lumbosacral Angle, Sacral Inclination and the Curvature of the Lumbar Spine during Aging
Authors: Amonoo-Kuofi U.S.
Published: July 2008

Measurements of the curvature of the lumbar spine are useful in the investigations of low back pain. It is unclear whether the degree of lumbar lordosis, sacral inclination and lumbosacral angulation are the same for all normal adults. Radiographic studies were carried out on the lumbar spines of subjects aged 9-61 years. Mean and 95% tolerance ranges of the values of lumbar lordosis, lumbosacral angle and sacral inclination for adult age groups up to the sixth decade are given. The results showed that all three parameters varied steadily with age. The pattern of changes differed in males and females. Females had greater angles than males. Sacral inclination appeared to be a more important determinant of the degree of lumbar lordosis. All three parameters showed a tendency to decrease after the sixth decade. The significance of the findings is discussed.
Transport of Siderotic Kupffer Cells to the Lung and Bronchial Excretion of Iron in Experimental Iron-Overload
Authors: Hertz T. , Düllmann J. , Nielsen P.
Published: July 2008

In 3,5,5-trimethylhexanoylferrocene-induced iron overload of rats, three different types of iron-loaded macrophages and derivatives thereof were found in t e lungs. On the basis of their localization and of their pattern of iron load it w is possible to distinguish: (1) Resident macrophages, showing an alveolar localization and a moderate iron content represented by lysosomal ferritin and haemosiderin. (2) Liver-derived macrophages and giant cells, as well as fragments of them. They showed an exclusive localization in capillaries and alveolar septa, and high concentrations of free ferritin molecules in addition to polymorphous ferritin- and haemosiderin-containing siderosomes. (3) Monocyte-derived intravascular pulmonary macrophages. Initially, they contained iron only as lysos -mal aggregates of ferritin and haemosiderin, as a result of phagocytosis of liver-derived macrophageal cell fragments. Later in iron overload, they also showc 1 free ferritin molecules in the cytosol and fused intrapulmonarily to giant cells. The resident as well as the liver-derived siderotic pulmonary macrophages provide a way for iron excretion through the airways.
Estradiol Influences the LH Response to Met-Enkephalin
Authors: Rubio M. , Carretero J. , Sánchez F. , Riesco J.M. , Vázquez Jr. R. , Vázquez R.
Published: July 2008

In order to test the possible role of estradiol in the response of the LH-adenohy-pophyseal cells to the administration of met-enkephalin in the albino male rat, an immunocytochemical (peroxidase-antiperoxidase) morphometric (cellular and nuclear areas and numerical density) and radioimmunoassay (LH serum levels at the moment of sacrifice) study was carried out. The intraventricular administration of met-enkephalin (150 µg in 25 µl of distilled water) does not produce any changes in the parameters considered. However, when the animals were pretreated with estradiol (chronically, 15 days), met-enkephalin produced a significant decrease in all the parameters considered.
Anatomical Study of the Blood Supply in the Human Shoulder Region
Authors: de la Garza O. , Lierse W. , Steiner D.
Published: July 2008

The blood supply of the shoulder muscles, ligaments and joint capsule was investigated by injection of silicone rubber into the arteria subclavia of postmo -tern cases. We show that the a. suprascapularis forms important anatomoses with other arteries in the region and is of greater importance for the blood supp y of the rotator cuff as hitherto believed. We also describe the a. subcoracoidea as a so far unknown branch of the a. axillaris.
Evidence of Drainage of Tungsten Particles Introduced in the Pleural Space through the Visceral Pleura into the Lung Parenchyma
Authors: Pereira De Sousa , Grande N.R. , Carvalho E. , Ribeiro A.
Published: July 2008

Studies of pleural clearance of calcium tungstate particles were made in the dog. By using scanning electron microscopy and elemental microanalysis, we show that mesothelial cells of the visceral leaflet of the pleura are also involved in the clearance of particles present in the pleural space. The histological study of lu g parenchyma shows many macrophages loaded with tungsten particles, and we conclude that this way may be an important pathway for the transmission of pathologic processes from the pleural space to the lung.
The Subcellular Localization of the Carbohydrate Epitope 3-Fucosyl-N-Acetyllactosamine Is Different in Normal and Reactive Astrocytes
Authors: Gocht A.
Published: July 2008

The carbohydrate epitope 3-fucosyl-N-acetyllactosamine (CD 15) is involved in cell-to-cell recognition processes in various tissues. In the present study the sub-cellular localization of CD15 was immunocytochemically studied in normal and pathological central nervous system fiber tracts of humans and rats. In normal human white matter of the brain, CD 15 immunoreactivity was found on the cell surface of astrocytes and within the cytoplasm of oligodendrocytes. In freshly demyelinated lesions of two human diseases (central pontine myelinolysis a d multiple sclerosis) strong cytoplasmic CD 15 staining was observed in reactive astrocytes. In normal rats CD15 immunostaining was restricted to the surface of astrocytes. In crush-induced lesions of rat optic nerves, however, astrocytes showed a cytoplasmic localization of CD15, 4 and 6 days after injury. In conclusion, abnormal localization of CD 15 in reactive astrocytes may be related to altered functional states of these cells during disease processes.
The Sensory Innervation of the Periodontium of the Third Premolar in Monodelphis domestica
Authors: Schulze C. , Spaethe A. , Halata Z.
Published: July 2008

Location and structure of sensory nerve endings in the periodontium of the third premolar in Monodelphis domestica have been investigated by means of light and electron microscopy. The periodontal cleft of the tooth is apically enlarged. The number of nerve endings increases towards apex. Three types of sensory nerve endings have been observed: free nerve endings, Ruffini nerve endings and lamellated corpuscles. Free nerve endings could only be identified by electron microscopy. Ruffini nerve endings are only incompletely surrounded by lamellae of the terminal Schwann cell. Protrusions of nerve terminals of the Ruffini corpuscles are anchored between bundles of collagen fibers. Small lamellated corpuscles occur exclusively in the apical portion of the periodontium. Ruffini and lamellated corpuscles are considered as part of a masticatory reflex feedback control system. Ruffini corpuscles detect tension, rapidly adapting lamellated corpuscles detect pressure and vibration in the periodontium. Free nerve endings may function as thermoreceptor or nociceptor.
Noradrenergic Fibers in the Pacinian Corpuscles of the Cat Urinary Bladder
Authors: Kumamoto K. , Ebara S. , Matsuura T.
Published: July 2008

Pacinian corpuscles in the cat urinary bladder were studied using the hematoxylin and eosin staining, formaldehyde-induced fluorescence histochemistry, immunohistochemistry for tyrosine hydroxylase (TH) and immunoelectron microscopy. The existence of catecholaminergic nerve fibers penetrating into the corpuscles was clarified. (1) About 10 Pacinian corpuscles which were mainly located in the subserosa were found in the lower one-third portion of each urinary bladder. (2) One or two corpuscles containing blue-green fluorescent fibers were detected in each bladder. These fibers were equivalent to TH-immunopositive varicose fibers using the avidin-biotin-peroxidase complex method. (3) Thin nerve fibers containing dense-cored vesicles were found in the corpuscle by immunoelectron microscopy. These fibers spirally encompassed a swollen sensory terminal at a distance in the inner core. According to the above findings, we discuss a modulatory function of the catecholaminergic fibers in this mechanoreceptor.
Postnatal Development of Skull Base, Neuro- and Viscerocranium in Man and Monkey: Morphometric Evaluation of CT Scans and Radiograms
Authors: Flügel C. , Schram K. , Rohen J.W.
Published: July 2008

Postnatal development of the neuro- and viscerocranium with special reference to the maxillodental structures was studied morphometrically by analyzing computer tomograms and radiograms of human and monkey heads of different age groups. The following parameters were used: the prognathic angle, the clivus angle, the palate-incisivus angle, the interincisival angle and the viscerocranial quotient. In the newborn primates including man, all parameters measured were relatively similar; postnatally, however, characteristic differences in the growth pattern between man and monkey were developing. In monkey, a marked prognathic growth of the viscerocranium was found associated with characteristic positional changes of the frontal teeth, whereas the growth of the neurocranium was retarded. Here, unlike the human, a flattening of the skull base was observed. In contrast, the human skull showed no major proportional changes during its postnatal development compared with the original spherical skull form of the newborn.
A Method to Estimate the Initial Length of Equine Tendons
Authors: Riemersma D.J. , Van den Bogert A.J.
Published: July 2008

A procedure is described by which the length of a tendon at the onset of loading is determined objectively. The procedure includes the fitting of third-order polynomial functions on the load-elongation data. The onset of loading is detected by an increasing fit of the polynomial by selective data reduction of the initial part of the load-elongation curve. The procedure results in an objective and reproducible definition of the zero strain level of a tendon.
In vivo Tendon Forces in the Forelimb of Ponies at the Walk, Validated by Ground Reaction Force Measurements
Authors: Jansen M.O. , Van Den Bogert A.J. , Riemersma D.J. , Schamhardt H.C.
Published: July 2008

The load distribution over tendinous structures in the equine forelimb was studied by computing forces from in vivo signals of implanted liquid-metal strain gauges in 5 ponies. For validation, these tendon forces were converted to joint moments, which were summed and compared to the calculated joint moments caused by the ground reaction force. Mean peak forces per kilogram body weight (n = 5) amounted to 5.2 N/kg for the superfical digital flexor tendon, 3.8 N/kg for the deep digital flexor tendon, 7.3 N/kg for the distal accessory (check) ligament and 8.4 N/kg for the third interosseous muscle (suspensory ligament). The maximal moment exerted by the tendons about the fetlock joint differed 11 ± 7% (average ± SD, n = 5) from the maximal ground reaction force moment, which difference amounted to 17 ± 15% for the coffin joint moments. These differences appeared to result to a substantial extent from errors in the moment arms. Therefore, the computed tendon forces were considered to be sufficiently reliable.
The Appearance of Direct Contacts between Auerbach’s Plexus and Smooth Muscle Cells in the Small Intestine of the Chicken during in ovo Development
Authors: Boros A. , Fekete É.
Published: July 2008

Direct contacts between the neural cell bodies of Auerbach’s ganglia and the longitudinal smooth muscle cells in the chicken small intestine were demonstrated by electron microscopy during the second half of embryonic development. The possible functional explanation of these contacts is discussed.
Cementum-Like Tissue Deposition on the Resorbed Pulp Chamber Wall of Human Deciduous Teeth Prior to Shedding
Authors: Sahara N. , Okafuji N. , Toyoki A. , Ashizawa Y. , Deguchi T. , Suzuki K.
Published: July 2008

In the later stage of exfoliation in human deciduous teeth, odontoclastic resorption takes place at the pulpal surface of the coronal dentin. However, this resorption does not continue until the teeth are shed, and the resorbed pulp chamber wall is usually repaired by cementum-like tissue deposition. In this study, we examined the formation and characteristics of the cementum-like hard tissue on the resorbed dentin surface in the pulp chamber of deciduous teeth prior to shedding. The site and degree of deposition of newly formed cementum-like tissue on the resorbed pulp chamber wall varied from tooth to tooth. Furthermore, they also showed compositional and structural variations. Generally, however, the matrix of the cementum-like tissue was composed of intrinsic collagen fibers, acellular or cellular. There was a tendency for acellular cementum-like tissue to be deposited on small and shallow resoφtion bays, whereas the cellular type was found on larger and deeper ones. In both cases, the surface of the deposited cementum-like tissue on the resorbed dentin surface usually became flat. However, unlike the cementum repair of resorbed areas on the root surface, no acellular extrinsic fiber cementum-like tissue was found on the resoφtion pulp chamber wall. Although the role of the repair of the resorbed pulp chamber wall with cementum-like tissue deposition just before shedding is unknown, it might play some role in the retention of deciduous teeth until shedding.
The Extracellular Matrix Components Laminin, Fibronectin, and Collagen IV Are Present among the Epithelial Cells Forming Rathke’s Pouch
Authors: Horacek M.J. , Thompson J.C. , Dada M.O. , Terracio L.
Published: July 2008

Cell-matrix interactions probably play a cooperative role with cell-hormone interactions to ensure normal differentiation of the adenohypophysis. The extracellular matrix (ECM) surrounding adult adenohypophysial cells contains laminin but its embryonic development has not been described. This study was carried out to test the hypothesis that adenohypophysial cells are associated with components in the ECM prior to cellular differentiation in the adenohypophysis. Fetuses were removed from Golden Syrian hamsters every 12 h from embryonic days 8.5-14. Coronal and sagittal 5-µm-thick sections of paraplast-embedded embryos were stained for fibronectin, laminin, or collagen IV using avidin-biotin immunoperoxidase staining. The adenohypophysial anlage was observed initially as a group of epithelial cells (Rathke’s pouch) in the roof of the stomatodeum in contact with a basement membrane. The basement membrane stained positively for laminin, collagen IV and fibronectin. Lighter staining for laminin, fibronectin and collagen IV was observed between the developing adenohypophysial cells in Rathke’s pouch. Proliferative activity was apparent in the antero-inferior region of Rathke’s pouch and resulted in the formation of the bulk of the adenohypophysis. Mesenchyme infiltrates the region between the base of Rathke’s pouch and the oral epithelium, thus separating the two. The basement membrane surrounding the pouch appears to become discontinuous in the regions of high proliferative activity. These results show that ECM components appear early during the development of adenohypophysial cells prior to their cellular differentiation into hormone-containing cells. This association between ECM components and developing adenohypophysial cells provides the anatomical basis for cell-ECM interactions to influence adenohypophysial development and differentiation.
Scavenger Macrophages and Central Macrophages of Erythroblastic Islands in Liver Hemopoiesis of the Fetal and Early Postnatal Mouse: A Semithin Light- and Electron-Microscopic Study
Authors: Sasaki K. , Iwatsuki H. , Suda M. , Itano C.
Published: July 2008

The livers of 12-day mouse embryos contain many hemopoietic cells in the hepatic cords and macrophages which are laden with large heterophagosomes in the sinusoids. Macrophages, as scavengers, engulfed circulating primitive erythroblasts from the yolk sac, as well as nuclei expelled from erythroblasts. At the 14th day of gestation, scavenger macrophages in mitosis were seen, extending long and thin cytoplasmic projections from their cell surface. At the 13-14 day of gestation, macrophages migrated from sinusoids into hepatic cords, and erythroblasts gathered around them, thus forming cell clusters designated as erythroblastic islets. Central macrophages formed a cell-socket-like structure on their cell surface for surrounding erythroblasts, reflecting the close association between macrophages and erythroblasts. In the erythroblastic islands, contained in late fetal and neonatal livers, erythroblasts have dissociated from the central macrophages having a starfish-shaped cell profile. The macrophage-erythroblastic association in the islands became less marked rapidly after birth.
The Harderian Gland of the Djungarian Hamster (Phodopus sungorus): Light- and Electron-Microscopical Investigations
Authors: Schreckenberger M. , Reuss S.
Published: July 2008

The Harderian gland of the Djungarian hamster Phodopus sungorus was investigated by light and electron microscopy in adult animals of both sexes, held under either long or short photoperiods. These glands have a tubuloalveolar structure. Epithelial cells were seen as small cylindric cells with a large, round nucleus located basally, many small vacuoles distributed throughout the cytoplasm (type I cells) or as rather broad cells with larger vacuoles (type II cells). The ratio of both cell types differed from 1:1 to 2:1 (type I:type II), regardless of the animal’s sex. In the electron microscope, abundant smooth endoplasmic reticulum of the vesicular type and rod-like or oval-shaped mitochondria of the crista type were very numerous; while Golgi complexes were rarely seen. ‘Membranous bodies’ were about nine times higher in amount in type II cells and were further augmented fourfold, in number, in glands of female animals. The few bundles of polytubular structures that were observed, were predominantly in type I cells. Myoepithelial cells were linked to the basal part of acinar cells by interdigitations. Many microvilli were observed at the apical portion of cellular membranes. Acinar cells predominantly showed signs of merocrine secretion, although apocrine secretion was seen in some cases. Under epifluorescence, red porphyrin fluorescence was seen predominantly in type I cells where it is mainly found apically. The comparison of animals held under either long or short photoperiods did not reveal any differences in Harderian gland structure.
Effect of Dietary Consistency on Matrix Synthesis and Composition in the Rat Condylar Cartilage
Authors: Hinton R.J.
Published: July 2008

Little is known of how the matrix of the condylar cartilage of the mandible changes in response to an alteration in local biomechanical circumstances, although this has been a habitual focus of studies of articular cartilage in the orthopedic literature. This study was formulated to investigate (1) whether matrix changes would occur in the condylar cartilage of rats fed a diet of soft consistency, a circumstance which would presumably reduce articular forces at the mandibular joint; (2) whether these changes, once established, could be reversed by restoring a diet of hard rat pellets, and (3) if these changes were localized to a particular region(s) of the cartilage. In the first experiment, male Sprague-Dawley rats were provisioned with either a soft, mushy diet or hard rat pellets beginning at weaning and subsequently sacrificed at 44 days of age. In the second experiment, all animals were initially given the soft diet, but in half a normal hard diet was reinstituted for 7 days prior to sacrifice at 44 days of age. In the third experiment, cartilages from rats fed soft and hard diets were subdivided into a superior fraction (that portion directly opposite the cranial articulation) and a posterior fraction. The results of experiment 1 showed the water content of the condylar cartilage to be significantly reduced in the soft-diet group, as well as one measure of [35S] uptake into sulfated glycosaminoglycans ([35S]sulfate dpm/µg uronic acid). Both wet and dry tissue weights of the condylar cartilage were greatly reduced in rats fed a soft diet. In soft-diet rats switched to a hard diet 1 week prior to sacrifice (experiment 2), water content, [35S] uptake and tissue weights were significantly increased compared with animals who remained on the soft diet. The data of experiment 3 indicated [35S]sulfate uptake to be significantly reduced in the superior but not the posterior portion of the cartilage in rats fed a soft diet; no changes in the other parameters were found. These results indicate that not only is condylar cartilage matrix metabolism and composition readily altered by a change in dietary consistency but also that the changes so produced can be reversed in as little as 1 week. In addition, this study confirms that the primary decrease in [35S] incorporation in soft-diet rats was found in that region of the cartilage most likely to be loaded during function. Although comparisons are difficult, these data differ somewhat from results of analogous studies in limb articular cartilage.
Ultrastructure and Barrier Properties of the Endolymphatic Duct in the Guinea Pig
Authors: Furuta H. , Mori N. , Hoshikawa H. , Sakagami M. , Sakai S.
Published: July 2008

The ultrastructure and barrier properties of the endolymphatic duct (ED) were examined by light and electron microscopy. ED epithelial cells were classified into two types: type I and type II duct cells. The type I duct cells were cuboidal or low columnar and were characterized by a convex apical surface and a few basal processes. The type II duct cells were squamous and were characterized by a flat apical and basal membrane, many small vesicles and a number of small pits along the basal membranes. After electrophoretic horseradish peroxidase (HRP) injection into the ED lumen, no HRP uptake into ED epithelial cells of either type was observed. There was no reaction product either in the lateral intercellular spaces beyond the tight junctions between ED epithelial cells or in ED subepithelial tissues. The ED epithelial cells were considered to play no active role in apical macromolecular absorption and to be impermeable to intra-luminal macro molecules.
Strain of the Musculus interosseus medius and Its Rami extensorii in the Horse, Deduced from in vivo Kinematics
Authors: Jansen M.O. , van Buiten A. , van den Bogert A.J. , Schamhardt H.C.
Published: July 2008

The in vivo strains of the musculus interosseus medius (suspensory ligament) and its rami extensorii (extensor branches) in the forelimb of the horse were determined from angular changes of the metacarpophalangeal and the distal interphalangeal joints. For this purpose, regression models were fitted to strains and joint angle combinations measured in in vitro limb loading experiments. The in vivo strains were computed from the kinematics of 8 horses at the walk, the trot and the canter. It was found that the extensor branches were strained about 1.0% at hoof impact, which indicates that they passively extend the interphalangeal joints just prior to impact and prevent flexion of the pastern joint just thereafter. The maximal strain of the suspensory ligament amounted to 3.4% at the walk, 5.6% at the trot and 6.3% at a slow canter.
Immunoelectron Microscopic Distribution of Actin in the Spermatids and Epididymal Spermatozoa of the Mouse
Authors: Prigent Y. , Dadoune J.P.
Published: July 2008

The distribution of actin in spermatids and epididymal spermatozoa of the mouse was examined by electron microscopy with immunogold procedures using two monoclonal antiactin antibodies. Actin was identified by immunoblotting of proteins extracted from either whole spermatozoa or tail fractions. In round spermatids, actin immunolabeling was detected in the subacrosomal space. Labeling increased during the elongation phase, and then decreased and completely disappeared before spermiation. No labeling was found in epididymal spermatozoa and residual bodies. Our results suggest actin redistribution or the absence of G-actin from the head to the flagellum in mature murine spermatids, as previously shown in other studies in various mammals.
Morphometric Analysis of Parathyroids in Hypophysectomized Rats in Normocalcaemic and Short-Term Induced Hypocalcaemic Conditions
Authors: Wild P. , Bächler C. , Bertoni G. , Schraner E.M.
Published: July 2008

The ultrastructure of parathyroid glands of hypophysectomized rats in normo- and hypocalcaemic conditions was qualitatively and quantitatively analysed. Parathyroid glands of both intact and hypophysectomized rats comprised cells of similar shape and staining intensity and of an equal number of cells in mitosis. Cell volume was not affected but the surface area of plasma membrane, RER and Golgi complex was increased in parathyroid cells after hypophysectomy. Parathyroid cells of both intact and hypophysectomized rats responded to hypocalcaemia by a drastic increase in surface area of the plasma membrane and a decrease in surface area of the Golgi complex. Since RER, Golgi complex and plasma membrane are concerned with secretion of parathyroid hormone, the data suggest that (1) the pituitary has either no effect on parathyroid cells, or a possibly stimulating effect can be compensated after hypophysectomy, or the pituitary even has a suppressive effect on parathyroid cells, and (2) the responsiveness of parathyroid cells to changes in serum calcium is unimpaired after hypophysectomy.
Morphological Alterations in the Elastic Fibers of the Rabbit Craniomandibular Joint following Experimentally Induced Anterior Disk Displacement
Authors: Ali A.M. , Sharawy Mohamed> , O’Dell N.L. , Al-Behery G.
Published: July 2008

Elastic fibers are important components of the connective tissue that attaches the articular disk of the craniomandibular joint (CMJ) to the skull and mandible. Biopsies of the articular disk proper and bilaminar zone (BZ) tissues from patients with anterior disk displacement (ADD) have shown previously that there is a marked loss of elastic fibers. In the present study, the effects of inducing ADD on the elastic fibers in the rabbit CMJ disk proper, BZ and condylar cartilage were investigated. The right CMJ was exposed surgically and the discal attachments were severed except for the BZ attachments. Then, the disk was displaced anteriorly and sutured to the zygomatic arch. The CMJs were removed after 1 2 or 6 weeks and processed for histochemical demonstration of elastic fibers. The results showed osteoarthritic changes following ADD, and a significant decrease in the number of the elastic fibers in the disk proper and BZ. The remaining elastic fibers were abnormal in their appearance and orientation. In addition, ADD led to the appearance of fine elastic fibers among the chondrocytes in the hyaline cartilage of the condyle that were not present in the cartilage of the control condyle. We conclude that induced ADD can lead to a significant loss of elastic fibers in the articular disk, and result in the appearance of elastic fibers within the cartilage of the mandibular condyle.
In vivo Effect of Gangliosides on Non-Obese Diabetic Mice
Authors: Papaccio G. , Chieffi Baccari G. , Mezzogiorno V.
Published: July 2008

Non-obese diabetic mice were administered 150 mg/kg body weight of Cronassial daily from the 5th to the 11th week of life. Animals were killed either at the end of the treatment with Cronassial (week 11) or at week 21. The results obtained demonstrated that the appearance of the insulitis in control and treated animals at 11 and 21 weeks did not show a significant difference. The only effect of ganglioside treatment was to slow the rate of rise in glycaemia and the progression of the islet cyto-architectural derangement. In our opinion, this is not sufficient to prove the effectiveness of this drug in reducing the final diabetes incidence.
Catecholaminergic Innervation of Oxytocin Neurons in the Paraventricular Nucleus of the Rat Hypothalamus as Revealed by Double-Labeling Immunoelectron Microscopy
Authors: Horie S. , Shioda S. , Nakai Y.
Published: July 2008

The catecholaminergic innervation of neurons that contain oxytocin in the paraventricular nucleus (PVN) of the rat hypothalamus was examined by a combination of methods in the same tissue sections at the electron-microscopic level as follows: (1) Rats were treated with 5-hydroxydopamine (5-OHDA) with peroxidase-antiperoxidase (PAP) staining of sections for oxytocin prior to embedding. (2) Preembedding immunoperoxidase staining with avidin-biotin complexes was used to demonstrate tyrosine hydroxylase (TH) activity, with postembedding staining with immunocolloidal gold for visualization of oxytocin. (3) Prior to embedding, a double-staining technique was used that was based on consecutive staining with silver-gold-intensified PAP complex and 3,3’-diaminobenzidine. We used an antiserum against oxytocin and an antiserum against dopamine-β-hydroxylase (DBH) for localization of antigens. We found that TH- and DBH-like immunoreactive terminals were distributed throughout the rat hypothalamus and were abundant in all parts of the PVN. Ultrastructural observations revealed 5-OHDA-labeled, TH- or DBH-like immunoreactive axon terminals that contained granular vesicles (70-80 nm in diameter) and small clear synaptic vesicles (30-50 nm in diameter). The terminals appeared at times to be making synapses with cell bodies and with the processes of oxytocin-containing neurosecretory neurons in the PVN. These findings provide morphological evidence for a direct synaptic influence of catecholaminergic elements on the secretory activity of oxytocin-containing neurosecretory neurons in the rat hypothalamic PVN.
Hippocampal p75 Nerve Growth Factor Receptor Immunoreactivity in Development, Normal Aging and Senescence
Authors: Kerwin J.M. , Morris C.M. , Johnson M. , Perry R.H. , Perry E.K.
Published: July 2008

Using the monoclonal antibody ME 20.4, p75 nerve growth factor (NGF) receptor immunoreactivity has been studied in the hippocampus and adjacent cortex in a series of 57 cases ranging in age from 24 weeks gestation to 95 years of age. The activity of the neurotransmitter-synthesizing enzyme choline acetyltransferase (ChAT), the activity of which is regulated by NGF, has also been determined in parallel experiments. p75 NGF receptor immunoreactivity was detected in the fetal neocortex as nerve terminal staining, potentially derived from basal forebrain neurons which were positive for NGF receptor, and was also localized in nerve cells of the cerebral cortex. Cortical reactivity for NGF receptor increased with age up to the 4th decade thereafter remaining constant. NGF receptor reactivity localized to neocortical neuronal cell bodies was not present in the postnatal or adult brain. Hippocampal reactivity for the NGF receptor was not present before birth appearing first in the postnatal period and thereafter showing an identical development pattern to the neocortex. ChAT activity in the entorhinal cortex and hippocampus partially paralleled NGF receptor development being present in the neocortex in the fetus but not in the fetal hippocampal formation and increasing postnatally to reach maximum levels in the 4th decade. Whilst entorhinal cortex ChAT values remain relatively constant with ageing, hippocampal ChAT declined with age after the 4th decade. The results may have implications for the aetiology of age-related cholinergic deficits in the hippocampus.
Local Vascular Contribution of the Superficial Palmar Arch
Authors: Gajisin S. , Zbrodowski A.
Published: July 2008

The aim of the present study was to establish a precise topography of the arterial supply of the different layers in the palm of the human hand. Two hundred upper extremities from fresh human cadavers aged 20–80 years were injected either by coloured latex or by India ink and gelatine. Some of our specimens were treated by the Spalteholz technique of transclarification, while some others were treated by acid corrosion. All of the specimens were dissected under the dissecting microscope. The superficial palmar arch (SPA) is the main vascular structure of the palm of the hand. Regardless of its size and of its variation, in addition to the common palmar digital arteries, the SPA supplies the superficial flexor tendons, flexor retinaculum, median and ulnar nerves, tendon of the flexor pollicis longus muscle, lumbrical muscles, palmar aponeurosis and the skin of the palm of the hand. These data may be of interest to those involved in hand surgery.
Microvascularization of the Common Tree Shrew (Tupaia glis) Superior Cervical Ganglion Studied by Vascular Corrosion Cast with Scanning Electron Microscopy
Authors: Chunhabundit P. , Thongpila S. , Mingsakul T. , Somana R.
Published: July 2008

Microvascularization of the superior cervical ganglion (SCG) of the common tree shrew (Tupaia glis) was investigated by the vascular-corrosion-cast technique in conjunction with scanning electron microscopy. It was found that the SCG of the tree shrew is a highly vascularized organ. It receives arterial blood from branches of the external and common carotid arteries which enter the rostral and caudal portions of the ganglion. These arteries give rise to a subcapsular capillary plexus before branching off to form a group of densely packed intra-ganglionic capillaries. Moreover, the intraganglionic capillaries tend to follow a tortuous course that is essentially parallel to the longitudinal axis of the ganglion, and they form anastomoses with each other. In additon, the intraganglionic capillaries are also connected to a subcapsular capillary plexus. The capillaries of the SCG converge into venules and collecting veins which subsequently drain rostrally and caudally into the systemic veins. However, neither a pattern of blood vessels resembling glomeruli nor a portal-like intraganglionic microcirculation was observed.