bluuebunny/crossref_metadata_2025 huggingface dataset:
Iron Overload of the Liver by Trimethylhexanoylferrocene in Rats
Authors: Düllmann J. , Wulfhekel U. , Nielsen P. , Heinrich H.C.
Published: July 2008

Iron-deficient female Wistar rats were fed a diet, which contained 0.5% trimethylhexanoylferrocene, over a 56-week period. This dietary iron loading resulted in a progressive siderosis and enlargement of the liver with a maximum iron content of 947.0 ± 148.0 mg (vs. 0.07 ± 0.04 mg in iron deficiency) and a maximum organ weight of 39.4 ± 6.6 g (vs. 6.9 ± 1.4 g in iron-deficient control rats). Up to 43 weeks, whole liver iron rose by increase in iron concentration (max. 28.0 ± 6.1 mg/g wet weight, w.w.) as well as by enlargement of the organ. Afterwards whole liver iron increased solely by ongoing hepatomegaly. At the commencement of iron loading, stainable iron was almost exclusively stored by hepatocytes equally throughout all areas of the liver lobule. Later, the distribution of iron-loaded hepatocytes became strikingly periportal, and, in addition, Kupffer cells as well as sinus-lining endothelia began to store iron. Animals with a liver iron concentration of more than 10.4 ± 0.75 mg/g w.w. showed no further increase in ferritin and haemosiderin within hepatocytes. Iron-burdened Kupffer cells/macrophages, however, accumulated permanently, hereby forming intrasinusoidal and portal siderotic nodules and areas. First signs of liver damage such as necrosis of single hepatocytes and mild fibrosis began at a liver iron concentration of 14.7 ± 1.4 mg/g w.w. With advancement of iron loading, focal necrosis of hepatocytes and iron-burdened macrophages took place, and significant perisinusoidal as well as portal fibrosis developed. Cirrhosis, however, the final stage of impairment in iron overload of the liver in humans, could not be induced in this animal model up to now.
Stereo Architecture of the Interface of the Epithelial Cell Layer and Connective Tissue Core of the Foliate Papilla in the Rabbit Tongue
Authors: Kobayashi K.
Published: July 2008

The three-dimensional relationship between the epithelial cell layer and the underlying connective tissue core (CTC) of the foliate papilla of the rabbit tongue was studied by scanning electron microscopy after removal of the epithelial cell layer. The foliate papillae were fixed in Karnovsky’s fixative, and the epithelial cell layers were exposed to long-term hydrochloric acid treatment (3.5 N HCl for 2-3 weeks at room temperature). The foliate papillae consisted of ridges and grooves located on the posterolateral margin of the tongue. They appeared as linear projections or ridges of lingual mucosa roughly perpendicular to the longitudinal axis of the tongue. These projections or ridges were parallel to one another and separated by grooves. After removal of the epithelium, two kinds of CTC folds appeared: one was the septal fold of CTC which runs in the central portion under each linear projection or ridge, and the other consisted of two sheets of groove side folds of CTC which run along both sides of the former and face the groove side epithelium. It was revealed that there are two sheets of septal epithelial processes, and each of them fits in between each septal fold and groove side fold of CTC. Numerous taste buds were located in the groove side epithelia, and their pores faced the surface of the groove. On the hollow surfaces that appeared on the surface of the groove side fold of CTC after removal of the epithelial cells with taste buds, nerve-terminal-like structures were encountered. Some openings of the ducts of small lingual glands were arranged linearly on the underside of the basal portion of each groove side epithelium.
Immunogold Identification of Prolactin Cells of Goats in Anoestrus, Pregnancy and Milk Production: Ultrastructural Variations
Authors: Sánchez J. , Bernabé A. , Navarro J.A. , Gómez M.A. , Gómez J.
Published: July 2008

Prolactin (PRL) cells of the goat adenohypophysis have been identified by the IgG-gold procedure with anti-sheep PRL serum. The secretion of these cells show differences in size and labelling in the three reproductive stages under study. Cells containing PRL can be grouped into low secretory activity cells (PRL-I) and high secretory activity cells (PRL-II) regarding their ultrastructure and functional significance. PRL-I were the most frequent cells in animals at the anoestrus stage, presenting numerous secretory granules and scarce development of the rough endoplasmic reticulum (RER) and Golgi complex (GC). At anoestrus and pregnancy stages there are frequent granule fusions, and the hormonal content partially disappears, perhaps by digestion. PRL-II cells were the most numerous at the lactating stage, presenting a moderate number of secretory granules and well-developed GC and RER. Some PRL-II cells of lactating animals exhibited scarce granules and numerous exocytosis suggesting a high secretory activity. In both anoestrus and pregnancy stages most granules range in diameter from 450 to 750 nm, in contrast to the lactating stage in which most granules range in diameter from 150 to 450 nm.
Timing and Sequence of the Events in the Development of Extraocular Muscles in Staged Human Embryos: Ultrastructural and Histochemical Study
Authors: Oguni M. , Setogawa T. , Matsui H. , Hashimoto R. , Tanaka O.
Published: July 2008

The ultrastructure and the appearance of glycogen were studied in the extraocular muscles of 14 externally normal human embryos (Carnegie stages 13–21). At stage 16, myofibrils with an immature Z line and glycogen granules appeared in the cytoplasm of the myoblast. The myoblasts came into cluster at stage 18, and fusion between the myotubes was observed at stage 20. At this stage, an M line appeared in the myofibrils. At stage 21, an A band with a Z line and an H band with an M line were observed, the sarcoplasmic reticulum appeared in the cytoplasm of the muscle fibers and glycogen increased in volume in the cytoplasm. In the previous study, we showed that the muscle-specific isoenzymes, such as creatine kinase, β-enolase and glycogen phosphorylase, appeared from stage 18 to 20 in the extraocular muscles. The previous findings and the present results suggest that the fusion of the muscle cells occurs in the period when some molecular markers of muscle differentiation are expressed in vivo.
Funktionelle Zytologie apokriner Analbeuteldrüsen der Hauskatze, Felis silvestris f. catus
Authors: Flachsbarth M.F. , Meyer W. , Sehwarz R.
Published: July 2008

Apocrine glands of the anal sacs in cats (Felis silvestris f. catus) were examined by transmission and scanning electron microscopy. The secretory cells exhibit a typical equipment with organelles that varied according to the season as well as the animal’s sex and state of reproduction. This can be mainly explained by seasonal differences in secretory activity. The cytological dynamics observed are, particularly, related to the smooth endoplasmic reticulum, which, for the first time, can be demonstrated in its crystalloid form in apocrine glands.
Analysis of the Tendinous Structure in Human Masticatory Muscles
Authors: Sato I. , Shimada K. , Ezure H. , Sato T.
Published: July 2008

In the masticatory muscles, the development of bundles of the tendon was examined: they were composed of many collagen fibers and a few elastic fibers. In the masseter muscle, the property of the tendon differs in the distribution and size of collagen fibers and elastic fibers in comparison with those of other masticatory muscles. This difference is concerned with the kinetic force for the stress or the stretch of each tendon and muscle during jaw movement.
Prothymosin Alpha Expression in Lymph Nodes and Tonsils: An Optical and Ultrastructural Study
Authors: Gallego R. , Rosón E. , García-Caballero T. , Fraga M. , Fortezab° J. , Domínguez F. , Beiras A.
Published: July 2008

Prothymosin α (ProTα) distribution in human and rat lymph nodes and human tonsils was studied by means of immunohistochemical methods, using specific antibodies raised against thymosin αL· We observed ProTα immunoreactivity in lymphoid cells of the germinal centers both in humans and rats. In human tonsils, positive cells were also seen in the basal layer of the surface epithelium. These results support the hypothesis that ProTα expression is restricted to actively proliferating cells. Immunoelectron microscopy revealed that ProTα was located in the nucleus, mainly in the border between euchromatin and heterochromatin.
Effects of Short-Term Treatment with Calcium on the Parathyroid Glands in Golden Hamsters of Different Ages, with Special Reference to Large Vacuolar Bodies
Authors: Emura S. , Shoumura S. , Utsumi M. , Hayakawa D. , Yamahira T. , Terasawa K. , Tamada A. , Arakawa M. , Isono H.
Published: July 2008

The effects of different ages on large vacuolar bodies in the parathyroid glands of golden hamsters after short-term treatment with calcium were investigated. In the parathyroid glands of the young and adult animals 15 min and the senile animals 15 and 60 min after administration of calcium, the percent area occupied by large vacuolar bodies was significantly increased as compared to that of the young, adult and senile control animals, respectively. These findings suggest that the percent area occupied by large vacuolar bodies is increased in response to acute hypercalcemia. It is thought that in the parathyroid glands suppressed by hypercalcemia there is a relationship between the percent area occupied by large vacuolar bodies and aging.
Unilateral Immobilization Affects Contralateral Rat Gastrocnemius Muscle Architecture
Authors: Heslinga J.W. , Rozendal R.H. , Huijing P.A.
Published: July 2008

In order to study the effects of unilateral short length immobilization on the contralateral gastrocnemius muscle (GM), length measurements were conducted on photographs taken in the active condition (tetanic plateau). Comparison of geometry of experimental and control muscles was made at optimum muscle length. The results show that a process occurred in the muscle which can be ascribed predominantly in terms of atrophy. This atrophy did not reach a maximum after 4 weeks but gradually increased in time. The altered conditions imposed on the muscle changed its architecture. It was shown that variables of the contralateral GM muscle are not representative of those of normally used muscles and should therefore not be used as control muscles for the determination of immobilization effects.
Neural Differentiation as an Expression of UV Sensitivity of Melanocytes
Authors: Iyengar B.
Published: July 2008

The present work is to study neural differentiation in melanocytes in relation to the cell cycle and UV exposure. Whole skin organ cultures of vitiliginous skin were exposed to a pulse of UV with and without prior Adriamycin treatment. It was observed that the highly dendritic marginal melanocytes are destroyed on UV exposure during the depigmentation phase but not during repigmentation. The melanocytes are resistant to UV destruction during the G2 phase as seen on Adriamycin treatment. They show a prominent increase in dendricity as well as biphasic activity to produce increased melanin and noradrenaline. Thus, the melanocytes form a UV-sensitive neural network in the skin. These responses are reminiscent of the repigmentation and depigmentation of coat color in animals exposed to extreme variations in the day/night cycles as seen at the poles.
Histo- and Immunocytochemical Characterization of the Neurons of the Mucosal Plexus in the Rat Colon
Authors: Mestres P. , Diener M. , Rummet W.
Published: July 2008

The mucosal plexus of the rat colon descendens is constituted of a network of nerves that, in contrast to most other segments of the digestive tract, contains also ganglia. The ganglia, consisting of neurons and glial cells, are located in the basal part of the lamina propria at distances between 100 and 1,200 µm. They are not vascularized. The neurons in these ganglia were characterized by means of: (1) the histochemical demonstration of acetylcholinesterase (AChE) activity, (2) the immunocytochemical identification of neurofilament proteins (NFP; 200 kD) and (3) their ultrastructure. The glial cells, which were AChE negative, could be distinguished from the neurons by differences in size and chromatin pattern. All neurons of the mucosal plexus reveal AChE activity in the perikaryon, but only parts of the axons are AChE positive. NFP-like immunoreactivity was detected in the perikarya but only in a minor part of the axons. These findings confirm previous light-microscopical observations and add new evidence for the existence of neurons (ganglia) in the mucosal plexus of the rat colon.
Electron Microscopy of the Mucosal Plexus of the Rat Colon
Authors: Mestres P. , Diener M. , Rummer W.
Published: July 2008

The ultrastructure of neurons, glial cells and axons of the mucosal plexus of the rat colon descendens was studied. Serial semithin sections and a re-embedding technique were used in order to localize the ganglia. The ganglia are free of blood vessels and connective tissue. The ratio of neurons to glial cells is approximately 1. Ganglia and nerve strands are enclosed by a basement membrane, without a well-defined perineural connective tissue. The neurons show a structure similar to other enteric plexus. Synaptic contacts were observed frequently in the neuropil, where nerve endings and varicosities show a diverse outfit in vesicles. The glial cells, which contain immunocytochemically detectable glial fibrillary protein, possess the same ultrastructural attributes in the intra- and extraganglionic localizations. In the nerves, axonic profiles and varicosities appear in close relation with glial cells or their processes. The distance between the nerves and their target cells, i.e. the enterocytes, is 0.5 µm or more with interposed basement membranes and fibroblasts.
Cytoplasmic Filaments in the Endothelial Cells of the Sheathed Capillary: An Ultrastructural and Immunocytochemical Study in the Pig Spleen
Authors: Takehana K. , Abe M. , Yamaguchi M. , Uchida T. , Inagaki M. , Yamamoto K. , Masty J. , Winnard A. , Ueda H. , Miyata H.
Published: July 2008

Cytoplasmic filaments of the endothelial cells of sheathed capillaries in the pig spleen were identified and their ultrastructure was studied. Two types of cytoplasmic filaments were found: intermediate filaments (diameter: 10 nm) which filled most of the interior of the cells, and thin filaments (diameter: 5 nm) which were located just beneath the cell membrane and filled the lateral cytoplasmic processes. In immunocytochemical preparations, the intermediate filaments were positive for vimentin and desmin, and were negative for keratin. Staining of the thin filaments with heavy meromyosin resulted in arrowhead formations. These observations suggest that the intermediate filaments maintain the cytoarchitecture, possibly protecting the cell from structural alterations induced by blood pressure changes. Concurrently, thin filaments may facilitate the passage of red blood cells and blood platelets through the interendothelial fenestrae of the sheathed endothelial cell to the reticular meshwork in the capillary sheath.
Further Examination of the Basicranial Anatomy of the Megachiroptera: A Reply to A.J. King
Authors: Wible J.R.
Published: July 2008

Four basicranial characters supporting a single origin of megachiropterans and microchiropterans have been identified by Wible and Novacek. King was not able to find two of these characters in specimens of the megachiropteran Pteropus and concluded that these characters be rejected in analyses of chiropteran phylogeny. To address King’s claims, the two characters in question (regarding the tegmen tympani and ramus inferior of the stapedial artery) are documented here for Pteropus. The discrepancies between this report and King’s appear to result from different criteria for identifying the tegmen tympani. Employed here are the criteria generally accepted by students of the mammalian chondrocra-nium.
The Pretectal Complex of the Rabbit: Distribution of Acetylcholinesterase and Reduced Nicotinamide Adenine Dinucleotide Diaphorase Activities
Authors: Caballero-Bleda M. , Fernandez B. , Puelles L.
Published: July 2008

The chemoarchitecture of the pretectal complex of the rabbit was examined in sections stained by acetylcholinesterase (AChE) and reduced nicotinamide adenine dinucleotide (NADH) diaphorase in the coronal, horizontal and sagittal plane. Twelve different subdivisions can be identified in the rabbit prectectum on the basis of the distribution of both histochemical markers. According to the standard terminology, the pretectal complex of the rabbit consists of: the nucleus of the optic tract; the anterior, posterior, olivary and medial pretectal nuclei; the nucleus of the posterior commissure; the periventricular subcommissural gray; the suprageniculate and internal suprageniculate nuclei, and the dorsal, lateral and medial terminal nuclei of the accessory optic system. The combined use of several sectioning planes and the histochemical mapping of AChE and NADH diaphorase have been of value in resolving the structural limits within transitional regions of the pretectum.
Non responsiveness of the Thyroid Gland to Goitrogen in the Early Neonatal Period in the Rat: Light- and Electron-Microscopic Observations
Authors: Shirai M. , Arishima K. , Yamamoto M. , Eguchi Y.
Published: July 2008

The thyroid response of fetal and neonatal rats to propylthiouracil (PTU) as a goitrogen was studied with observation of the thyroid glands by light and electron microscopy. On day 19 of gestation and on days 1,3,5 and 8 after birth, fetal and neonatal rats were given a subcutaneous injection of PTU and were autopsied 2 days later. PTU induced conspicuous goiters in fetal rats but did not in neonatal rats aged up to day 5 after birth. Beyond that age, PTU again induced goiters. Histologically, the follicular cell height in goitrous thyroid glands was significantly increased. Ultrastructurally, follicular cells in goitrous thyroid glands often had colloid droplets and lysosomes. It seems that nonresponsiveness of the thyroid glands in early neonatal rats to goitrogen is due to a temporary decline of the pituitary activity of thyrotropin secretion. About 5 days or more after birth, the pituitary-thyroid system begins to operate again in response to goitrogen.
Long-Term Effects of Alloxan Induced Diabetes on the Nucleus ventralis posterolateralis in the Thalamus of the Rat
Authors: Tay S.S.W. , Wong W.C.
Published: July 2008

The present paper describes the long-term ultrastructural changes in the nucleus ventralis posterolateralis of the thalamus of male Wistar rats after alloxan-induced diabetes. Degenerating dendrites were characterized by an electron-dense cytoplasm with scattered endoplasmic reticulum and ribosomes. Degenerating axon terminals were characterized by an electron-dense cytoplasm and clustering of small spherical agranular vesicles. Degenerating axon terminals formed axosomatic synapses with seemingly normal cell bodies and axodendritic synapses with normal as well as degenerating dendrites. Degenerating axons (both myelinated and unmyelinated) were readily encountered in the neuropil. Activated microglial and astrocytic cells in the neuropil were in the process of phagocytosis or had residua in their cytoplasm.
Elbow Extensor Muscles of the Horse: Postural and Dynamic Implications
Authors: Ryan J.M. , Cobb M.A. , Hermanson J.W.
Published: July 2008

Based on histochemical and immunohistochemical evidence, horse elbow extensor muscles are composed of two morphologically distinct muscle groups. The long and lateral heads of the triceps brachii are large, predominantly type II (presumed fast) muscles. The long and lateral heads of the triceps together account for 96% of the weight of the elbow extensors (long head of triceps is 81%). The long and lateral heads contain three histochemical fiber types: types I, IIa and IIb. Type I muscle fibers account for approximately 18 and 27% of the fibers in the long and lateral heads of the triceps, respectively. In the lateral head, type Πa and lib fibers account equally for the remaining 70% while in the long head of the triceps type lib fibers predominate (50%) over type Ha fibers (32%). In contrast, the much smaller medial head of the triceps (2% of triceps mass) and the anconeus (2% of mass) contain almost exclusively type I muscle fibers. It is hypothesized that the medial head and anconeus, with their slow fibers, contribute to the postural maintenance of the forelimb by preventing flexion at the elbow joint during passive stance. The larger long and lateral heads, with their generally fast fiber populations, are most likely important during dynamic activity.
The Suprascapular Nerve as Re-Interpreted by Its Communication with the Phrenic Nerve
Authors: Kodama K. , Kawai K. , Okamoto K. , Yamada M.
Published: July 2008

A particular nerve bundle which may be called phrenicosuprascapular communication is, although only rarely, met with in various forms in man. By teasing, fibres of this communication are revealed to belong to the most anterior components of the brachial plexus, being closely associated with anterior nerves such as the phrenic, accessory phrenic, subclavius and even pectoralis. It is, therefore, obvious that the nervus suprascapularis conveys anterior fibres. It may be interpreted that the anteriormost nerve fibres may be separated from the main cord(s) and form an irregular network or plexus for themselves. It should be stressed that the n. suprascapularis consists of all the anterior components of the brachial plexus and that this is an anterior nerve.
Intrinsic Organization of the Paramedian Pontine Reticular Formation of the Cat
Authors: Gioia M. , Bianchi R.
Published: July 2008

A morphoquantitative analysis was carried out to clarify the cytoarchitectural organization of the paramedian pontine reticular formation (PPRF) which is considered to be an important site in the control of eye movements. The study was carried out on the cat, using the Golgi staining method. The topographic position and detailed structure of the neurons were demonstrated using morphoquantitative methods. On the basis of their neuronal arborization, fusiform neurons and two types of multipolar cells were identified. Fusiform neurons show dendrites which are given off from the two poles of the small- to medium-sized cell body. The arborization generally runs caudorostrally, ending inside the PPRF. These neurons are ubiquitous. Type 1 multipolar neurons, the most frequent elements of the neuronal population (60%), have a small- to large-sized cell body from which 2 or 3 primary spiny dendrites and the axon emerge. Their dendritic field is oval and generally oriented in the vertical plane. These neurons are scattered everywhere in the PPRF. Type 2 multipolar cells are large neurons endowed with numerous primary spiny dendrites constituting a wide round dendritic field and with a thick axon. They are located almost exclusively at the boundaries of the PPRF and preferentially in the caudal region. The characteristics of the neurons suggest that the fusiform cells may play an interneuronal role, while the multipolar neurons could have both a projective function and an important receptive role for the afferent fibers to the PPRF. The lack of homogeneity found among the multipolar neurons is in agreement with the variety of projective elements shown by functional investigations. This study which describes the detailed pattern of the neuronal population provides the structural support for the many morphofunctional and physiological studies of the PPRF.
Morphological Study of Fetal Nasopharyngeal Epithelium in Man
Authors: Gulisano M. , Montella A. , Orlandini Zecchi , Pacing P.
Published: July 2008

In 30 human fetuses between 8 and 13 weeks of intrauterine life the lateral wall of the nasopharynx was examined by light microscopy and transmission am scanning electron microscopy. In the subjects between 8 and 9 weeks in utero the mucosa displays still an immature appearance, being mono- or bistratifiet and lacking the characteristic structures of the respiratory epithelium. Nevertheless, signs of differentiation are to be noticed, with the presence of two distinc cellular types that, in the later periods, will give rise to ciliated cells and microvillus-provided cells. An almost complete differentiation will be reached at 12–13 weeks in utero, even if goblet cells are still lacking in the examined zone during the considered period. Nonrespiratory types of epithelium, such as transitional or squamous, were never found in the studied subjects.
Monoclonal Antibodies against Rat Kidney Antigens
Authors: Okot-Opiro P. , Baier W. , Celio M.R.
Published: July 2008

The proximal tubule of the nephron is subdivided into three structurally and functionally distinct segments, which can be differentiated with the help of special methods. With the aim of producing selective markers for these three portions of the proximal tubule, we raised monoclonal antibodies against the brush border membranes of the rat kidney. Immunohistochemistry was carried out with eleven different monoclonal antibodies to sections of rat kidney and other tissues at the light- and electron-microscopical level. These monoclonal antibodies mainly detect antigens located on the brush border of the proximal tubule, and they allow a distinction between its three segments. However, some antibodies also recognize other portions of the nephron, or even the glomerulus or stromal elements. Sites recognized by the antibodies are not limited to the kidney, but staining is observed on the intestinal brush border, the intralobular ducts of the pancreas, the bile canaliculi of the liver and on the macrophage clusters of the spleen. These antibodies are interesting reagents which can be applied to study biochemical differences between brush border membranes. In addition, they recognize antigenically related sites in other organs with reabsorptive or secretory tasks.
Fine Structure of the Dorsal Lingual Epithelium of the Japanese Monkey Macaca fuscata fuscata
Authors: Iwasaki S. , Yoshizawa H. , Suzuki K.
Published: July 2008

Filiform papillae, which were densely distributed all over the dorsal surface of the lingual body, were crown-shaped, with a central, circular area that sloped in the anterior direction and several branches that surrounded it in a semicircle from the back of the central area. Dome-shaped, fungiform papillae were scattered among these filiform papillae. At the posterior end of the lingual body, there were four circumvallate papillae. Prominent microridges and elevated intercellular borders were widely distributed in the central area of the filiform papillae and the inteφapillar region. On the surface of the branches of the filiform papillae, microridges were rarely seen. On the surface of the fungiform papillae, indistinct microridges were observed. Histologically, the dorsal lingual epithelium revealed three different regions: the epithelium on the anterior side of the filiform papillae, the epithelium on the posterior side of the filiform papillae and the inteφapillar epithelium. Whereas the basal and suprabasal cells are similar throughout, differences characterize the intermediate and surface layers. Keratohyalin granules appear predominantly in the intermediate layer in the epithelium on the anterior side of filiform papillae. In the epithelium on the posterior side of the filiform papillae, no keratohyalin granules occur and, instead, tonofibrils are prominent. The cells become significantly flattened. In the inter-papillar epithelium, no keratohyalin granules are visible, and the tonofilaments occupy almost the entire cytoplasm of most cells in the intermediate and surface layers. The cells are larger in volume in these layers.
How Little Luteal Tissue of Rats Is Needed to Maintain Pregnancy till Term -An Experimental Verification
Authors: Chatterjee A. , Chatteree R.
Published: July 2008

Surgical reduction of luteal tissue to about 20% of its total mass on day 5 pc was found to maintain gestation till term. A high degree of fetal loss was, however, evident. An identical surgical manipulation at the end of maximal luteal maturity, that is, on day 16 pc, resulted in normal maintenance of gestation. Fetal growth and their survival rate were found to be comparable to controls. An exclusive surgical extirpation of corpora lutea, on the other hand, either on day 16,17,18 or 19 was found to cause 100% fetal loss by day 23. However, progesterone replacement therapy concurrently with surgical luteal ablation till day 20, or surgical extirpation of the entire luteal mass when shifted on day 20, led the pregnancy to term. Present experimental findings, therefore, suggest that only about 20% of the functionally matured luteal mass until day 20 is essentially enough to maintain an ideal pregnancy status till term.
Morphology of Corpuscular Receptors in Hairy and IMonhairy Human Skin as Visualized by an Antiserum to Protein Gene Product 9.5 Compared to Anti-Neuron-Specific Enolase and Anti-S-100 Protein
Authors: Ramieri G. , Stella M. , Calcagni M. , Teich-Alasi S. , Cellino G. , Panzica G.C.
Published: July 2008

The present study elucidates the morphology of encapsulated receptors in human skin by means of immunohistochemistry for the recently characterized neurospecific marker protein gene product 9.5, in comparison with neuronal specific enolase and S-100 protein. Only two types of corpuscles are identified, Meissner’s corpuscles and simple coiled corpuscles. Moreover, this investigation reveals that though regional specialization may exist with regard to the encapsulated receptor density, the comparison of hairy and nonhairy skin does not reveal important differences.
Nerve Growth Factor Receptor-like Immunoreactivity in the Human Spinal Cord
Authors: Kerwin J.M. , Morris C.M. , Perry R.H. , Perry E.K.
Published: July 2008

Nerve growth factor (NGF) receptor-like immunoreactivity has been demonstrated in the normal human adult spinal cord using the monoclonal antibody ME20.4. Intense immunoreactivity was associated with fibres and terminals in the substantia gelatinosa. In lamina IX the neuropil demonstrated punctate staining, the motor neurons themselves being negative. At thoracic levels occasional neurons of the intermediolateral column cell group were NGF receptor positive. Fine axonal and punctate terminal reactivity was observed in the gracile fasciculus, corresponding to axons in transverse section. Similar, though slightly less dense immunoreactivity was observed in the cuneate fasciculus. The demonstration of NGF receptor immunoreactivity may provide a useful marker of sensory innervation in the human spinal cord.
Lymphoid Tissue Changes during Early Syngeneic Pregnancy in theRT1u Rat
Authors: Habbal O. , McLean J.
Published: July 2008

An active immunological response by the female to mating and pregnancy is important, if not essential, to successful reproduction. Alloantigens which have been demonstrated on spermatozoa include histocompatibility antigens. In the enigmatic success of the fetal allograft, the conceptus survives owing to failure of the mother either to initiate or complete the process of rejection. In this study, AO(RT1u/AgB2) female rats were caged with male rats of the same strain. Observations were obtained from the first 5 days of their postcoital period, identifying lymphoid tissue changes which are due to the presence of the ejaculate and early products of conception in the female reproductive tract. A significant increase in intrathymic proliferation by day 3 is thought to be a hormonal effect induced by the cervical stimulation at mating. The postcoital exodus of lymphocytes from the thymus is possibly in response to coitus and induced by the seminal plasma to safeguard the implanting conceptus.
Prenatal Growth Pattern of the Human Maxilla
Authors: Lee S.K. , Kim Y.S. , Lim C.Y. , Chi J.G.
Published: July 2008

Regarding maxillofacial morphogenesis there has been a long debate on the growth of the maxillary structure. Using 120 normal fetal maxillae of gestational ages from 16 to 41 weeks, palatal radiograms and frontal histologic sections were made. We have observed two pairs of accentuated growth areas in the fetal maxillae and named them primary growth centers to formulate the maxillary trapezoid (MT) by radiologic image. The MT is formed by four primary growth centers that are best demonstrated by palatal radiograms of the fetal maxilla as well as by frontal histologic sections. The dimensional increase in the MT during the fetal period is documented and statistically analyzed. From this series of results, we have suggested that the growth centers which demarcate the MT are the basic structures of the developing human maxilla. It was also found that the four primary growth centers are the most active sites for maxilla formation until 20 weeks of gestation and thereafter the growth of the maxilla is enhanced by the participation of the intramembranous bone formation along the periphery. This was in contrast to the central primary growth centers that have already finished maturation in the early fetal period and remain only as a peripherally radiating arrangement of thick trabecular bones.
Histological Study of the Temporomandibular Joint Capsule: Theory of the Articular Complex
Authors: Fenoll Bermejo , Sequeros Gonzalez , Gonzalez Gonzalez
Published: July 2008

The findings of the histological study of the human temporomandibular joint confirm that the cranium and the lower jaw are joined by two temporomandibular articular complexes (one on the left and another on the right side), each made up, in turn, of two joints – a condylomeniscal condyloarthrosis and a reciprocally fitting meniscotemporal joint. Both these joints are surrounded by short capsular bands which stretch from the condyle to the meniscus and from the latter to the temporal bone and form the true joint capsules. Longer bands which extend from the condyle to the temporal bone may be regarded as reinforcements passing over two articulations.
Aluminium Hydroxide Uptake in the Stomach and in the Intestine of the Rat: A Histochemical Study
Authors: Moré J. , Fioramonti J. , Buéno L.
Published: July 2008

Using the histochemical stains aluminon, solochrome azurine and solochrome cyanine, intracellular binding of aluminium was examined in the mucosa of the stomach, duodenum, jejunum and ileum of adult rats. A first group of rats (n = 42) was sacrificed 1, 3, 6, 12, 24, 48 and 96 h after a single (300 mg × kg–1) oral administration of aluminium hydroxide. A second group of animals (n = 30) received daily the same dose of Al(OH)3 and was euthanatized after 3, 4, 5, 6 and 7 days of treatment. Aluminium deposits occurred only in the antral glands of the stomach and in rats treated for at least 3 days. The reactive deposits are located in the cytoplasm of the upper glandular cells and in the lumen of the antral glands. These results suggest that aluminium is absorbed through the antral mucosa and may be re-excreted through the glandular mucus flow into the digestive lumen where it will be absorbed again. We hypothesize that the metal could act as a delayed-effect drug.
Presence of Melanin in the Cat Pineal Gland
Authors: Calvo J.L. , Boya J. , Garcia-Mauriño J.E. , Rancaño D.
Published: July 2008

Light- and electron-microscopic features of pigmented cells in the cat pineal gland are described. These cells were observed throughout postnatal life from the second postnatal day to the oldest cats studied (up to 13 years old). No apparent relationship was observed among the amount of pigment and the animal age or sex. Pigmented cells showed a preferential localization at the ventral surface of the pineal gland near its distal end. The pineal pigment was histochemically identified as melanin. Pineal pigment granules showed ultrastructural features similar to melanocyte melanin granules.
Structural Characterization of the Mandibular Condyle in Human Fetuses: Light and Electron Microscopy Studies
Authors: Ben-Ami Y. , Lewinson D. , Silbermann M.
Published: July 2008

Mandibular condyles from 18- to 20-week-old human fetuses were examined in the light and electron microscope with particular attention to intratissue organization and extracellular matrix. In the human fetus the condyle has been divided into five layers: (1) the most superficial, articular layer, (2) chondroprogenitor cell layer, (3) condroblast cell layer, (4) nonmineralized hypertrophic cell layer, and (5) mineralized hypertrophic cell layer. The articular layer is rich in collagen fibers (mostly of the type I collagen), but the cells seldom divide. By contrast, in the chondroprogenitor cell layer and upper part of the chondroblastic cell layer mitosis gives rise to new cells. The matrix in the latter layer is composed of thick banded ‘lucent’ fibrils in a loose feltwork of granules representing cartilage proteoglycans. The daughter cells in the progenitor cell layer undergo differentiation which is apparently completed along the lower border of the mineralized hypertrophic cell layer – the ossification front. The matrix in the hypertrophic cell layer reveals distinct matrix vesicles that undergo mineralization and subsequently coalesce to form larger sheets of mineralized extracellular matrix. Mineralized cartilage serves as a backbone for new bone formation as marrow-derived osteoblasts and osteoclasts attach to remnants of mineralized cartilage, which enables the turning on of the remodeling cycles involved in new bone formation. It can be concluded that the process of endochondral ossification as has been reported in lower animals is recapitulated in the human fetus, thus the dynamics associated with condylar morphogenesis is maintained through phytogeny.
Sensitivity of the Fetal Rat Pituitary-Adrenal System to Corticotropin-Releasing Factor in Organ Culture
Authors: Yamamoto M. , Arishima K. , Takizawa T. , Shirai M. , Eguchi Y.
Published: July 2008

Six groups of adrenal glands from 17-day fetal rats were explanted to organ culture for 2 days. In one group, adrenal gland was cultured alone, and in the remaining five groups adrenal gland was cultured with pituitaries from fetuses ranging in age from 14 to 18 days. In each of the groups, half of the cultures had corticotropin-releasing factor (CRF) added to the medium. A histometric parameter utilized the size of adrenocortical cells as an indicator of sensitivity of the pituitary-adrenal system. When 17-day adrenal gland was cultured alone, addition of CRF did not cause any enlargement of cortical cells. When the adrenal gland was cultured with two 14-day pituitaries, cortical cells were enlarged. Addition of CRF to this culture induced no further change. With two 15-day pituitaries in the presence of CRF, cortical cells were slightly larger than those in the absence of CRF. With 16- to 18-day pituitaries, a marked hypertrophy of cortical cells was induced, and the addition of CRF caused further acceleration in their enlargement. These results suggest that, in organ culture, 14-day pituitary can release some adrenocorticotropic hormone (ACTH) with or without additional CRF. Older pituitaries (16- to 18-day) can apparently release an amount of ACTH in the presence of CRF that is greater than their own spontaneous ACTH secretion.
Distribution of Calcitonin Gene-Related Peptide and Substance P-lmmunoreactive Nerve Fibers and Their Correlation in the Periodontal Ligament of the Mouse Incisor
Authors: Kato J. , Tanne K. , Ichikawa H. , Matsuo S. , Wakisaka S. , Akai M. , Kurisu K. , Sakuda M.
Published: July 2008

The distribution of calcitonin gene-related peptide (CGRP)- and substance P (SP)-immunoreactive (IR) nerve fibers and their correlation in the periodontal ligament of mouse incisors were examined by indirect immunofluorescence. Both CGRP-IR and SP-IR thin nerve fibers were abundant in the apical and middle third of the periodontal ligament. In the lingual portion of the incisal periodontal ligament, these nerve fibers were localized in the alveolar half of the periodontal ligament and were observed as free nerve endings. No CGRP-IR and SP-IR specialized nerve endings, such as Ruffini-like corpuscles, were observed. In the labial periodontal ligament, CGRP-IR and SP-IR nerve fibers ran along the incisal axis. The distribution of CGRP-IR nerve fibers was very similar to that of SP-IR nerve fibers.
Degranulation of Rough Endoplasmic Reticulum in M Phase and Adenosine-Triphosphate-Treated Interphase Cells Is Reversible
Authors: Sit K.H. , Bay B.H. , Wong K.P.
Published: July 2008

In the preferential harvesting of rounded mitotic (M phase) cells of human Chang liver monolayer cultures by mechanical agitation in Ca2+-free phosphate-buffered saline, degranulation of endoplasmic reticulum (ER) was observed. Mitotic cells are known to have a series of Ca2+ transients and, without being subjected to Ca2+-free washings, did not have degranulated ER. Quiescent cells incubated with 0.7 mM adenosine 5’-triphosphate (ATP) in Ca2+-free HEPES-buffered saline produced very similar ER degranulations. Confocal argon laser imaging of fluo-3-loaded cells showed a Ca2+ transient peaking at 2 min after ATP treatment. In the absence of extracellular Ca2+ transients of Ca2+ elevation in the cytosol would exit the cell in a down-gradient, draining the ER Ca2+ stores. Substituting ATP with 1 µM brominated A23187 calcium ionophore in the incubation that contained 1-100 mM CaCl2, respectively, did not produce ER degranulation, thereby excluding raised cytosolic Ca2+ per se as the cause of ER degranulation. In fact, incubation with 0.7 mM ATP in the presence of 1-5 mM CaCl2 failed to produce ER degranulation. ER degranulated cells, from treatment with ATP without extracellular Ca2+ as well as from Ca2+-free washings at M phase, could be rescued by subsequent incubation in growth medium that contains Ca2+ whereupon the rounded cells re-flatten (a round-to-flat change) and have well-defined rough ER. It therefore seems possible for Ca + depletion, or at least a reduction, to be causally related to ER degranulation. If that were the case, ER granularity would appear to be a facultative rather than a constitutive state.
Distributions of Antibovine-Pepsinogen-Positive Cells in Glandulai Regions of Forestomach in the Bactrian Camel, Camelus bactrianus
Authors: Amasaki H. , Guirung G. , Nakamura M. , Ogimoto K.
Published: July 2008

The present paper describes mucous cells in the forestomach glandular regior which immunoreacted to antibovine pepsinogen serum in adult and young bac trian camels, Camelus bactrianus (female, 25 years old; female, 6 months old from Hilar Inner Mongolia, People’s Republic of China, in August 1988). Thest immunoreactive cells in forestomach glandular regions also reacted to Alciai blue (pH 1.0) and/or periodic acid-Schiff. Cross-reactivity of antibovine pep sinogen serum against extracts from the forestomach glandular region waí analyzed by Western blotting, supporting that this serum could detect pepsir and/or pepsinogen in the bactrian camel. It was suggested that mucous cells ii forestomach glandular regions produce pepsinogen molecules.
Increase of DNA Synthesis in Uterine Adenomyosis in Mice with Ectopic Pituitary Isograft
Authors: Sakamoto S. , Mori T. , Singtripop T. , Kawashima S. , Suzuki S. , Kudo H. , Sawaki K. , Nagasawa H.
Published: July 2008

Ectopic pituitary isografts (EPI) have been found to induce a high incidence of uterine adenomyosis in SHN mice. All the SHN mice given EPI in the right uterus at 40 days of age developed uterine adenomyosis, and more than 80% of mice showed the genesis of subserosal nodules, an advanced state of adenomyosis, 65 days after EPI. Activities of both thymidylate synthetase and thymidi re kinase, i.e. DNA-synthesizing enzymes in de novo and salvage pathways of pyrimidine metabolism, respectively, were significantly increased in EPI-induced uterine adenomyosis to approximately 2-fold those in normal control uteri. Bromodeoxyuridine-immunoreactive cells were regarded as the cells in S phase, a id the number in the endometrial epithelium and stroma in EPI-induced uterine adenomyosis was more than 1.5-fold that in normal control uteri. EPI may affect the genesis of uterine adenomyosis generally, but not locally, because there were no differences between the right uterus with EPI and the left without EPI in the incidence of adenomyosis, histology or DNA-synthesizing enzyme activities.
Are Ranvier’s Nodes of the Central Nervous System also Artifacts by Preparation?
Authors: Monteiro R.A.F. , Rocha E.
Published: July 2008

Recent research on peripheral nerves of six species of vertebrates concluded that Ranvier’s nodes may be artifacts by preparation. As a consequence, the question as to whether or not Ranvier’s nodes of the central nervous system may also be artifacts was logically raised. The ultrastructural data concerning our field of research (the cerebellar cortex) support the notion that Ranvier’s nodes are real features in the central nervous system; otherwise, the occurrence of vesicular outpockets establishing, along myelinated axons, well conspicuous en passant nodal synapses cannot be explained.
Ultrastructure and Collagen Composition of the Myo-Fascial Junction in Rat Calf Muscles
Authors: Järvinen M. , Jozsa L. , Kvist M. , Lehto M. , Vieno T. , Isola J. , Kannus P.
Published: July 2008

The collagen composition and ultrastructural organization of the myo-fascial junction was studied using immunohistochemical techniques and electron microscopy. At the myo-fascial junction, a small amount of type-III collagen was found; however, the major collagen component was the type-I collagen. On the longitudinal sites of muscle cells, there were deep recesses and, within these, finger-like structures containing sarcomers. In these recesses and in the fingerlike structures of the myo-fascial junction, the sarcolemma was thickened (three times) in a similar way to the basal lamina at the myotendinous junction. Thin collagen fibers were closely associated with the thickened sarcolemma of the finger-like structures.
In vitro Effects of Elastase on Rabbit Craniomandibular Joint Articular Disks
Authors: O’Dell N.L. , Sharawy M. , Starcher B.C. , Pennington C.B. , Cudiaa R.P.
Published: July 2008

This in vitro study correlates morphologic and radioimmunoassay (RIA) findings on the effects of elastase on the elastic fibers that are found in the rabbit craniomandibular joint (CMJ) articular disk. Articular disks were removed from rabbit CMJs at necropsy, and cut sagittally into two pieces which were incubated in 0.3 ml of phosphate-buffered saline containing either 0, 12.5, 25 or 50 units of porcine pancreatic elastase for either 1, 3 or 24 h. The quantitative RIA findings correlated well with the qualitative light-microscopic observations in that both methods showed a reduction in the amounts of elastin in the CMJ disks following enzyme treatment. However, the morphologic appearance of most of the elastase-treated disks suggested that the destruction of the elastic fibers was more extensive than was suggested by the results of the RIA which indicated that some elastin remained in the tissues of the disks even when the highest enzyme level and longest incubation period were combined. The results of this study also support the interpretation that the resorcin-fuchsin-stained fibers in the rabbit CMJ disk are elastic fibers.
Quantification of Thymic Innervation in Juvenile and Aged Rats
Authors: Zirbes T. , Novotny G.E.K.
Published: July 2008

Thymic innervation has been quantified using silver impregnation and light microscopy on 5 juvenile and 5 aged rats. There is an increase in innervation density of the thymus with age, exceeding the reduction of thymic volume due to involution. The density of innervation correlates inversely with thymic volume. From previous studies, we conclude that thymic innervation is confined to the extraparenchymal compartment. Ultrastructural morphometry shows this compartment to maintain its volume during involution of the remaining thymic tissue. Related only to the extraparenchymal compartment, the innervation increases by a factor two with age.