bluuebunny/crossref_metadata_2025 huggingface dataset:
Influence of Food Restriction during Gestation on Craniofacial Growth of the Weanling Rat
Authors: Pucciarelli Hector M. , Oyhenart Evelia E.
Published: July 2008

Holtzman rats were subjected to food restriction during gestation or lactation, or both periods (overall stress). At weaning, male pup skulls were measured and female brains and cranial masticatory muscles were weighed and a neuromuscular index was calculated. It was found that gestational protein-calorie malnutrition (PCM) without suckling restoration accounted for about 30% of the growth delay observed under overall stress. That effect disappeared after a normal suckling restoration. Under the same conditions of maternal food restriction in both periods, growth delay in the offspring was greater during lactation than gestation. As in lactation, craniofacial changes during gestational restriction were due to an adjustive response of bone growth to PCM. This response seemed to accrue from an altered relationship between the growth of the brain – less sensitive and highly restorable – and the growth of the masticatory muscles – more sensitive and less restorable. Some degree of delay in orthocephalization would be the skeletal outcome of such adjustive neuromuscular response.
Effect of Clomiphene Citrate on the Ovary of a Wild Rat, Bandicota bengalensis
Authors: Sahu Abhiram
Published: July 2008

The effects of clomiphene citrate (0.3 or 3.0 mg/kg body weight/day) for 10 consecutive days on the ovary of a wild rat, Bandicota bengalensis, were studied. The low dose of clomiphene decreased the number of nonatretic follicles larger than 400 µm in diameter, increased atresia in follicles smaller than 200 µm, inhibited granulosal mitosis in follicles less than 200 µm and between 401 and 600 µm in diameter and inhibited thecal mitosis in follicles smaller than 400 µm and larger than 600 µm. The high dose of clomiphene increased the number of follicles between 201 and 400 µm, decreased the number of follicles larger than 600 µm, increased atresia in follicles of 51–400 µm and increased granulosal mitosis in follicles of 201–400 µm diameter. In both the doses, clomiphene inhibited the ovulation rate (p < 0.005), with 25 and 35% of the rats being anovulatory in low and high doses, respectively. In addition, clomiphene caused irregularity in the estrous cycles associated with increased cycle length. These results suggest that the clomiphene-induced partial inhibition of ovulation is possibly through its action on follicular growth and atresia mainly in nonantral ( < 200 µm) and mature follicles (401–600 µm).
Acute Administration of Chloral Hydrate Depletes Cardiac Enzymes in the Rat
Authors: Trulson Michael E. , Ulissey Michael J.
Published: July 2008

The arterioles of the left cardiac ventricle were analyzed histochemically to determine the effects of an acute administration of chloral hydrate on key enzymes of aerobic and anaerobic metabolism, as well as the hexose-monophosphate shunt in rats. Significant changes were noted in three of the 5 enzymes examined. Our data suggest that nontoxic levels of chloral hydrate can cause impaired coronary metabolism.
Ultrastructure of Cementum Formation on Partially Formed Teeth in Dogs
Authors: Hayashi Y.
Published: July 2008

Cementum crystals and matrix vesicles on the root surface of partially formed teeth in dogs were examined with a transmission electron microscope. Fine filamentous crystals were observed in the cementum calcifying fronts. The running pattern was mainly parallel to the root surface in the apical region and perpendicular to the root surface in lateral and coronal regions. Matrix vesicles were observed at the apical half of the periodontium, but not observed at the coronal region. These findings suggest that the parallel-arranged cementum would become the light-microscopic lamellar type and the perpendicular one the light-microscopic dense-line structrure when fully developed. Moreover, cementum formation occurs due to two kinds of mechanisms: participation of matrix vesicles and secondary calcification (= additional cementogenesis).
Adrenomedullary Chromaffîn Cells of the Rat
Authors: Singh D.N.P. , Mathew T.C.
Published: July 2008

Adrenomedullary chromaffin cells of the rat were studied at the ultrastructural level. Chromaffin cells contained a large population of electron-dense-core vesicles of two types, one very electron-dense (norepinephrine) and the other moderately electron-dense (epinephrine). The vesicles showed an even distribution pattern in the cytoplasmic matrix. No physical contacts were observed between cytoplasmic and vesicle membranes to indicate exocytosis, a mechanism frequently observed in the hamster. For chromaffin cells to be used as a transplantable source of dopamine, both the cells and vesicles must survive the trauma of denervation and vascular elimination or alternatively acquire the two factors from the transplantation site.
Halothane Anesthesia Alters Cerebral Enzymes: A Histochemical Study in the Rat
Authors: Trulson Michael E. , Ulissey Michael J.
Published: July 2008

Cerebral forebrain arterioles and neuropil were analyzed histochemically to determine the effects of halothane anesthesia on key enzymes of aerobic and anaerobic metabolism, as well as the hexose monophosphate shunt in rats. Significant changes were noted in all five enzymes examined in arterioles, while no changes were observed in the two enzymes involved in aerobic metabolism in the neuropil. Our data suggest that surgical anesthetic levels of halothane can impair forebrain metabolism and lead to altered electrophysiological responses.
Chloral Hydrate Anesthesia Alters Cerebral Enzymes in the Rat
Authors: Trulson Michael E. , Ulissey Michael J.
Published: July 2008

Cerebral forebrain arterioles and neuropil were analyzed histochemically to determine the effects of chloral hydrate anesthesia on key enzymes of aerobic and anaerobic metabolism, as well as the hexose monophosphate shunt in rats. Significant decreases were observed in cytochrome oxidase, and β-hydroxybutyrate dehydrogenase in arterioles, while glucose-6-phosphate dehydrogenase and isocitric dehydrogenase showed a significant increase and lactate dehydrogenase showed no significant change. In the neuropil, cytochrome oxidase, isocitrate dehydrogenase and glucose-6-phosphate dehydrogenase showed significant increases following chloral hydrate administration, while β-hydroxybutyrate dehydrogenase and lactate dehydrogenase showed no significant changes. These data suggest that surgical anesthetic levels of chloral hydrate can impair forebrain metabolism which may lead to altered electrophysiological responses.
Halothane Depletes Cardiac Microvasculature Enzymes in the Rat
Authors: Trulson Michael E. , Ulissey Michael J.
Published: July 2008

Left ventricular arterioles from Sprague-Dawley rats were analyzed histochemically to determine the effects of halothane administration on key enzymes of aerobic and anaerobic metabolism, as well as on key enzymes of the hexose monophosphate shunt. Significant decreases occurred in cytochrome oxidase (–42%) and β-hydroxybuty-rate dehydrogenase (–57%). No significant changes were observed in isocitrate dehydrogenase, glucose-6-phosphate dehydrogenase, or lactate dehydrogenase. These data suggest that anesthetic levels of halothane can cause impaired metabolism in the coronary microvasculature.
Microtubule-Like Structures in Developing Oocytes of the Mongolian Gerbil (Meriones unguiculatus)
Authors: Rune G.M.
Published: July 2008

Oocytes of sexually mature Mongolian gerbils, Meriones unguiculatus, of all stages of the estrous cycle were investigated electron-microscopically during foUiculogenesis. Oocytes of advanced stages of development contained numerous microtubule-like structures, which ran through the cytoplasm without any preference in direction. Initially they occurred in oocytes of secondary follicles. In the cross-section view they were either round showing an inner diameter of approximately 16 nm, or they were slightly triangle-shaped. Incomplete tubules were also present. The highest organization was found in oocytes of preovulatory follicles, whereas they vanished during atretic processes. A possible role of the tubules during the maturative growth of the oocyte is discussed.
Castration Cells in Rat Adenohypophysis After Long-Term Alcohol Consumption
Authors: Somer L. , Wrobel K.-H. , Schimmel M.
Published: July 2008

Histological and ultrastructural changes of hypophyseal gonadotropic cells of rats which received a 15% solution of ethyl alcohol for 6 months were studied. Light microscopy revealed hyperplasia and hypertrophy of these cells; some contained a vacuole of varying size. Ultrastructural analysis showed that this vacuole originated from, and anastomosed with, dilated cisternae of the granulated endoplasmic reticulum. Vacuolated cells in the pituitary of alcoholized rats were identical with cells observed after surgical or chemical castration. The development of these alcohol-induced castration cells is achieved in four stages.The first stage was characterized by beginning hydropic degeneration and other still reversible alterations. Cells in the second and third stages seemed already irreversibly on their way to decay.The fourth stage was represented by typical signet-ring cells. Our results offer a morphological basis to the adoption of a biphasic effect of alcohol on gonadotropic secretion.
Atresia of the Right Atrial Ostium of the Coronary Sinus
Authors: von Lüdinghausen M. , Lechleuthner A.
Published: July 2008

A case of asymptomatic congenital occlusion of the ostium of the coronary sinus is described. The myocardial venous drainage was maintained via a persistent left superior vena cava as well via ectatic, widened atrial veins of the dorsal wall of the left atrium. The study shows that complete ostial occlusion of the coronary sinus does not reduce cardiac venous drainage. The view of the literature allows a comparison with the comprehensive classification of coronary sinus anomalies.
Vascularization of the Myocutaneous Latissimus dorsi Flap
Authors: Friedrich Wolfgang , Herberhold Claus , Lierse Werner
Published: July 2008

This study reports on investigations of the thoracodorsal artery by injection studies.This artery has a long proximal extramuscular course before it enters the muscle. A consistent neurovascular hilum was found at a considerably constant location on the inferior muscle surface, 2–3 cm medial to its lateral edge and about 5 cm distal to the inferior scapular border. A constant branching pattern of the thoracodorsal artery into a lateral and a medial vessel stem was found. A high number of muscle-perforating arteries form a dense network in the cutaneous and subcutaneous layer. The thoracodorsal artery supplies the whole cutaneous area adjacent to the latissimus dorsi muscle plus a streak of about 2 cm at the medial and distal muscle borders. The presented anatomical landmarks are useful for locating the neurovascular hilum, and the intramuscular course of the thoracodorsal artery for exploration of the vessel by Doppler sonography or dissection. The length of the pedicle and the relatively big vessel gauge are good anatomical markers for the free transfer of a latissimus dorsi flap.
Rat Embryogenesis following Exposure to Alcohol and Nicotine
Authors: Woo Nobby D. , Persaud T.V.N.
Published: July 2008

Pregnant Sprague-Dawley rats were treated from day 9 through 12 of gestation with either ethanol (12.5% v/v in physiological saline, 0.015 ml/g, i.p.) and nicotine (16.7 mg/kg, s.c), alone or in combination. Corresponding groups of animals received physiological saline in a similar manner and these served as controls. Embryos were recovered on gestational day 12 and were quantitatively assessed on the basis of 16 recognizable developmental endpoints (morphological scores). The head and the crown-rump lengths of the embryos were also measured. Embryos exposed to nicotine and to ethanol-nicotine were significantly affected in their development whereas those exposed to ethanol alone were spared.
A Quantitative Approach to Spatial Variation of Human Cerebral Sulci
Authors: Keyserlingk Graf v. , Niemann K. , Wasel J.
Published: July 2008

The surfaces and the sulci of the lateral hemispheres of 30 postmortem brain specimens were three-dimensionally measured. The coordinates of all the structures registered constitute a digital brain model. The models were scaled linearly until they fitted a defined cuboid. Then all the models within the reference volume, each represented by a set of points, were considered together. The reference volume was divided into small cubic volume elements (voxels). Two parameters of the voxels were studied: the point density of each structure per voxel and the contribution index which designates how many of the hemispheres contribute points to a certain voxel.The latter parameter may serve as an index for the presence probability of a sulcus, which means the probability with which a sulcus will be contained in a defined volume element. The presence probability of a sulcus corresponds well with its first appearance in embryological development. Spatial variation in the early developing principal sulci is far less than in those which develop in later stages. As regards some defined regions of the brain, statements about the probable location of cortical areas in relation to the commissural system can be made.
Effect of Altered Masticatory Function on [3H]-Thymidine and [35S]-Sulfate Incorporation in the Condylar Cartilage of the Rat
Authors: Hinton Robert J.
Published: July 2008

The response of the condylar cartilage to alterations in compressive joint reaction forces in vivo has been little studied. In an attempt to reduce or eliminate the occlusal forces resulting from mastication or incision, male weanling rats were fed a soft diet requiring little chewing and/or had their incisors clipped every other day. Incorporation (dpm/µg DNA) of [3H]-thymidine and [35S]-sulfate was significantly decreased relative to controls in the incisorclipped group, but not in the soft-diet group. Animals having both treatments also exhibited significantly lower incorporation values than controls, suggesting the importance of incision for loading at the mandibular joint. These data corroborate in vitro studies which suggest that compressive forces can affect mitotic activity and synthesis of proteoglycans in the condylar cartilage. However, additional factors, both hormonal and biomechanical in nature, may be important in the in vivo environment.
Fine Structure of Melanocytes and Macrophages in the Harderian Gland of the Mouse
Authors: Shirama Kazuhiko , Harada Tetsui , Kohda Masanori , Hokano Masami
Published: July 2008

The presence of dendritic cells containing melanin granules has been demonstrated employing silver impregnation and electron microscopy in the interstitial tissue of the Harderian gland of the mouse.Two types of melanocytes either with or without the various developmental stages of melanin granules were found in the gland. Cells with developing granules were more dendritic and contained a largenumber of cytoplasmic organelles.The other cells were ellipsoidal or slender in shape and contained few cytoplasmic organelles and a large number of fully melanized granules but no developing granules. In general the granules of the Harderian gland melanocytes resembled granules from other organs (particularly the skin of the eyelids).The general size range of the granules was 0.2–0.9 µm. Each granule was enclosed by a membrane.The Harderian gland macrophages contained fully pigmented melanin granules of various sizes. The granules were enclosed by a membrane either singly or in groups. Some of the melanin granules within the phagosomes showed signs of degradation, revealing the underlying matrix.
In vitro Growth of the Nasal Septal Cartilage of the Rat in a Serum-Free Culture Medium
Authors: Kvinnsland Steinar
Published: July 2008

To evaluate the capacity for growth of cartilage in vitro, the cartilaginous nasal septum was cultured in a serum-free medium in short- and long-term incubation periods. The proliferative activity was assessed by relating counts per minute (cpm) obtained in the liquid scintillater after [3H]-thymidine incorporation with the DNA content of the tissue under investigation. Cell proliferation was interpreted as being synonymous with the DNA synthesizing activity or the cpm/µg DNA ratio. Short-term incubation (24 h) tended to show the same proliferative activity which we have previously found in vivo and as autotransplants, showing that the presence of serum seems to be of little importance under these conditions. Long-term incubation in a serum-free medium tended to show a gradual loss of proliferative activity, emphasizing the need for either serum or other growth-promoting factors as necessary for continued normal proliferation of cartilage in vitro.
Microvasculature of the Bear Heart Demonstrated by Scanning Electron Microscopy
Authors: Anderson Wesley D. , Anderson Bettina G. , Seguin Randolph J.
Published: July 2008

Morphological features of the coronary microvasculature were examined in ten Black bears (Ursus americanus). Tissue samples were collected for scanning electron microscopy from five animals, and vascular casts of the coronary vessels were prepared from five. Each portion of the microvasculature examined had specific morphological characteristics which may contribute to the control of blood flow. All indications from the present study suggest that the structure of the coronary microvasculature in the Black bear is similar to that of mammalian species previously examined.
Qualitative and Quantitative Observations on the Structure of the Schwann Cells in Myelinated Fibres
Authors: Pannese E. , Ledda M. , Arcidiacono G. , Frattola D. , Rigamontí L. , Procacci P.
Published: July 2008

Various morphological features of the Schwann cells of myelinated fibres in the lizard thoracic spinal roots were studied, and, when possible, quantified using morphometric methods. About 0.8% of the Schwann cells are binucleate and some display clusters of microvilli along the irtternodes.The percentages of the cytoplasmic area of the Schwann cell occupied by the following cytoplasmic components were determined: mitochondria, Golgi apparatus, granular endoplasmic reticulum, smooth endoplasmic reticulum, multivesicular bodies, dense bodies, autophagic vacuoles, peroxisome-like bodies, lipofuscin granules and lipid droplets. Linear relationships were found between the sectional areas of the mitochondria and granular endoplasmic reticulum of the Schwann cell and both the length of the profile of the Schwann cell plasma membrane and the size of the related axon. The results obtained are compatible both with the hypothesis that the mitochondria and granular endoplasmic reticulum of the Schwann cell are involved in the production and storage of proteins for the plasma membrane of this cell, and with the hypothesis that these organelles are involved in the production and storage of protein metabolites which are subsequently transferred to the related axons.
Exceptions to Cajal’s Neuron Theory: Communicating Synapses
Authors: Santander Gonzalez , Cuadrado Martinez , Sáez Rubio
Published: July 2008

Ultrastructural images of some neurons and their synaptic connections, belonging to the nucleus of the periaqueductal grey substance in the domestic cat mesencephalon, are shown. The finding that some axosomatic synapses showed an open communication between the pre- and postsynaptic portion attracted our attention. In this way a continuity is made between the presynaptic bouton of one neuron (axon) and the postsynaptic portion of the other (neuronal soma). Synapses having these interneuronal communications could be denominated communicating synapses. Accepting Cajal’s neuron theory and his law of neuronal independence, it is very difficult to interpret these images. We wonder if this type of communicating synapses could be the exception that proves the rule of the neuron independence.
Renal Microvasculature of the Black Bear (Ursus americanus)
Authors: Anderson Bettina G. , Anderson Wesley D. , Seguin Randolph J.
Published: July 2008

This study of the Black bear (Ursus amerícanus) was undertaken to provide basic information related to structural modifications in the renal microvasculature that might provide insight into the drastic alteration in renal urinary output that occurs during winter sleep. Vascular casts, as well as light microscopy and scanning electron microscopy, were used to study the vascular components of the juxtaglomerular complex and related vessels. Histologically, arterial cushions were readily identified at the origin of the afferent arterioles. In the area of the juxtaglomerular complex, the wall of the afferent arteriole appeared to be highly modified. The smooth muscle cells at this site demonstrated a change in morphology and orientation, and the diameter of the arteriole was altered. The pattern of the vascular casts at the origin of the afferent arteriole varied from that portion at the glomerulus, suggesting a modification of the vascular wall near the renal corpuscle. Although the morphology of the renal microvasculature of the Black bear is similar to that of other mammals in some aspects, it is dissimilar to that of other carnivores and of the human kidney in that there are structural modifications of the afferent arteriole that may contribute to a reduction of blood flow to the nephron during winter sleep.
Regeneration of D-Galactosamine-Traumatized Rat Liver with Natural Protoberberine Alkaloids from Enantia chlorantha
Authors: Virtanen Pauli , Lassila Veijo , Njimi Thomas , Mengata Denis Ekotto
Published: July 2008

Experimental liver injury was provoked in test rats with intraperitoneal injections of D-galactosamine. Traumatized rats received further intraperitoneal injections of Hepasor, a protoberberine alkaloid mixture from Enantia chlorantha (Annonaceae). Biochemical assays from blood plasma, serum alanine transferase, serum alkaline phosphatase, serum creatinine, serum hydroxyproline and serum calcium were done and liver and kidney samples for histological processing were taken. The biochemical results obtained indicate a marked influence by Hepasor on the serum alanine transferase activities and serum hydroxyproline values in female rats, but more accidental ones in male rats. A reduction in serum alkaline phosphatase activity and the serum creatinine values was also found, being also dependent on sex. The histological findings in the liver sections of female rats show that 1 week Hepasor therapy greatly furthers the healing process in a D-galactosamine-pretraumatized liver, eliminating megalocytosis, contraction of chromatines and other disorders in the cell architecture. The inhibitory effect of Hepasor on proceeded traumatization caused by D-galactosamine was nearly complete.
Eine sichere Methode zur infraklavikulären Punktion der Vena subclavia
Authors: Anderhuber Friedrich , Lechner Peter , Tesch Norbert P.
Published: July 2008

Investigations of 25 human cadavers, using various anatomical techniques, led to the development of a safe and simple method of subclavian venipuncture. This method was tested with special regard to possible complications. The authors describe the guidelines for the choice of the point where the skin has to be penetrated as well as of the point towards which the needle has to be directed. While the latter is situated a little beyond the spinous process of the seventh cervical vertebra, the other is determined as follows: the distance between the acromion and the sternoclavicular joint is divided into three parts, and the junction between the medial and central third of this distance is marked on the skin. Starting from this point a vertical is dropped towards the line between the acromion and the sternal angle. The point of intersection between this line and the vertical is where the cannula penetrates the skin. After a distance of between 2.5 and 4.5 cm the top of the needle reaches the subclavian vein. Even if the vessel is pierced through and through, no complication such as pneumothorax, laceration of arteries, lesions of the adjacent nerves, etc., can occur. Using this method the authors performed catheterization of the subclavian vein in 200 patients, and there were no complications at all.
Tracing of Lateral Pterygoid Muscle-Related Neurons in the Trigeminal Brainstem Nuclei in the Rat
Authors: Rokx J.T.M. , Van Willigen J.D.
Published: July 2008

Retrograde transport of fluorescent tracers (diamidino yellow and true blue) was used to study the arrangement of brainstem neurons innervating the lateral pterygoid muscle in the rat. The lateral pterygoid motoneurons were located in the dorsolateral (jaw-closing) part of the trigeminal motor nucleus with clear somatotopy in the caudal part of the nucleus. No muscle-related neurons were present in the mesencephalic trigeminal nucleus. Histological examination of serial sections of lateral pterygoid muscles confirms the notion that, at least in the rat, this muscle is devoid of muscle spindles.
Afferent Projections to the Mesencephalic Trigeminal Nucleus in the Rat
Authors: Rokx J.T.M. , Luiten P.G.M. , Van Willigen J.D.
Published: July 2008

The anatomical pathways from the parvocellular reticular formation and medulla oblongata to the mesencephalic trigeminal nucleus (Mes V) were investigated in the rat by means of the anterograde tracer Phaseolus vulgaris leukoagglutinin. P. vulgaris was injected into the rostral ventromedial medulla, rostral and caudal ventrolateral medulla, the parvocellular reticular formation and surrounding regions. Rostral medullary regions and the parvocellular reticular formation projected to Mes V although the bilaterality, extent and density of the projections originating in these reticular structures showed clear variations. In experiments in which dorsolateral reticular areas were involved, we found the projections to the bilateral trigeminal nuclei to be most prominent. More caudal areas, including the spinal trigeminal nucleus caudalis, showed no projections to MesV.The present experiments show, for the first time, the existence of ipsilateral and crossed projections from the reticular formation to the MesV.These pathways are possibly involved in direct modulation of trigeminal reflexes.
The Facial Motor Nucleus of the Dog
Authors: Costa-Llobet C. , Prats-Galino A. , Arroyo-Guijarro J. , Ruano-Gil D.
Published: July 2008

In this study, an area of 953.2 µm2, a diameter of 36.7 µm and a circularity factor of 0.74 have been established for the neurons of the facial motor nucleus of the dog. Significant differences (p < 0.01) were observed by comparing the means of some of the parameters determined in the six cytoarchitectonic subdivisions of the facial motor nucleus described in a previous study. Moreover, the neurons tend to increase in size in the caudocranial direction.
Effects of Prostaglandin E2 on Alveolar Bone Resorption during Orthodontic Tooth Movement
Authors: Chao Chung-Fu , Shih Chung , Wang Teen-Meei , Lo Tai-Hua
Published: July 2008

Twenty Sprague-Dawley rats weighing 280–300 g were divided into two groups often animals each.They were treated by daily submucosal injections of 50 µg prostaglandin E2 (PGE2) per kilogram body weight into the region below the apex of the left first maxillary molar (experimental) or vehicle into the region below the apex of the right first molar (control), for a period of 5 days.The animals of the first group were sacrificed immediately following the treatment period, while those of the second group were sacrificed 5 days after the treatment period.Twenty-two hours prior to sacrifice, a piece of latex orthodontic elastic was secured to the adjacent area between the first and second maxillary molars of both sides of each rat by using two mosquito hemostats.The periodontál ligament (PDL) mesial to the mesiobuccal root of the first maxillary molar was assayed for changes in PDL cell factors. The results showed that immediately following the 5-day treatment period the left PDL had a significant decrease in the total number of fibroblasts and a significant increase in the total number of both osteoclasts and nuclei per osteoclast, while no significant changes in the osteoblasts when compared with those of the right control PDL. The left PDL of animals which were sacrificed 5 days after the treatment period revealed a significant decrease in the number of total fibroblasts and only a slight decrease in both numbers of total osteoclasts and total nuclei per osteoclast, but again no significant changes in osteoblasts when compared with those of the right control PDL. The reduction in the number of total fibroblasts in the left PDL was attributable to the submucosal injection of PGE2 which probably inhibited mitoses of fibroblasts. In addition, submucosal injection of PGE2 might also have induced transformation of monocytes into osteoclasts and an increase in the osteoclast-resorptive activity, although its effect is short-acting. All the above findings demonstrated that treatment with 50 µg PGE2/kg/day for 5 consecutive days inhibited the proliferation of PDL fibroblasts and activated alveolar bone resorption during orthodontic tooth movement.
Effect of Gonadal Activity on the Cranial Dimorphism of the Rat
Authors: Dahinten Silvia L. , Pucciarelli Héctor M. , Moreno Felix R.
Published: July 2008

Weanling rats of both sexes were submitted to either castration, or castration together with periodic injections of testicular extract to males or of ovarian extract to females. Control and experimental animals were sampled at 63 days of age. Cranial differentiation between sexes was estimated by Mahalanobis D2 distances. The controls showed a significant sexual cranial difference. Orchidectomy decreased cranial differences and this effect was compensated by injections of testicular extract. On the other hand, oophorectomy increased cranial differences, which were diminished by injections of ovarian extract. Sexual cranial dimorphism in the normal rat seems to be the result of a counteracting effect between testicular and ovarian hormonal secretions.
Microcirculation of the Coronary Band of the Equine Hoof
Authors: Marais J. , Masty J.
Published: July 2008

Scanning-electron-microscopic examination of corrosion casts was used to investigate the microcirculation of the coronary border of the equine hoof. Numerous peg-shaped capillary plexuses derived from arterioles extended distally from the dorsal branches of the digital arteries parallel to the hoof wall. The plexuses varied in length and consisted of a fine network of interconnected capillaries that converged to join a centrally situated venule. These centrally situated venules within the papillary plexuses gave rise to a vast venous plexus deep to the coronary band.
Degeneration of Adrenergic Nerves in the Gail-Bladder of Cholecystitis Patients
Authors: Qayyum M.A. , Fatani J.A. , Khuaiter Saleh al , Maleika S.S.
Published: July 2008

The adrenergic innervation of the gall-bladder of healthy persons and patients suffering from cholecystitis has been studied following fluorescence histochemical methods.The normal gall-bladder is moderately innervated by adrenergic nerve fibres. Fine nerve fibres have been observed in the lamina propria, fibromuscularis and serosa. Catecholamine-containing fluorescent cells have been observed at different sites and their possible role as chemoreceptors and their endocrine nature have been reaffirmed. Adrenergic nerve fibres show signs of degeneration in cholecystitis as is evidenced by swelling of the nerve fibres and enhanced intensity of fluorescence in fluorescent cells.
Effects of Ovarian Steroids on Vaginal Smears in the Rat
Authors: Monies G.S. , Luque E.H.
Published: July 2008

A correspondence between the appearance of vaginal smears and the layers of the epithelium from which the cells had desquamated was established in untreated rats during the estrous cycle, in control ovariectomized rats and in spayed rats injected with either estrogen or progesterone. The technique for preparing and staining the smears (modified Shorr’s staining procedure) is outlined. A simplified.system of classification which allows the accurate identification of the various stages of the reproductive state in the rat is described. Standing estrus, as well as the influence of estrogen on spayed rats, is characterized by marked cornification of the cells and the disappearance of leukocytes. At the end of estrus, the cornified layer is sloughed off and invasion by leukocytes occurs. During diestrus, as well as in untreated ovariectomized rats, the vaginal contents consistently lack cornified cells whereas leukocytes are very plentiful. Proestrus follows diestrus: the vaginal smear is devoid of leukocytes and characterized by nucleated epithelial cells. Pregnancy, as well as the influence of progesterone on ovariectomized rats, is also characterized by epithelial growth and desquamation but at different rates, resulting in the presence of intermediate cells, and polymorphs and mucus forming a noticeable background to the smear. Since vaginal smears display cell pictures characteristic for each hormone after administration of estrogen or progesterone, exfoliate cytology is a good indicator of the stage of the reproductive state in the rat.
Morphological Studies of the Neuromuscular Mechanism Shifting from Sucking to Biting of Mice
Authors: Kubota Kinziro , Narita Noriyuki , Ohkubo Kenichi , Shibanai Shunji , Nagae Kazuki , Kubota Miyuki , Odagiri Noriko , Kawamoto Tetsu
Published: July 2008

In order to give a neuroanatomical evidence to the mechanism of shifting from sucking to biting, we investigated in prenatal, newborn and postnatal mice whether there is a time difference in the neurogenesis of the neurons relative to sucking and biting or in the histogenesis of their peripheral effector organs by the HRP labeling technique and electron microscopy.The results obtained are as follows. (1) At birth the facial motoneurons exceed the trigeminal motoneurons in cell area and development. (2) After birth, the trigeminal motoneurons grow rapidly and outstrip the growth of the facial motoneurons at the age of 6 days. (3) Thereafter, the cell area of both neuron types continues to increase gradually. (4)The initial sign of the alpha motor end plates is found in the orbicularis oris muscle innervated by the facial nerve in 17-day-old fetuses, while that of the trigeminal nerve is delayed in the masseter muscle of 18-day-old fetuses. (5)The initial sign of the muscle spindle appears with the sensory terminals in the masseter muscle of 17-day-old fetuses and the fundamental structure of the muscle spindle is formed in 4-day-old youngs. (6) Myelination of the facial nerve begins in 3-day-old youngs, while that of the trigeminal nerve becomes apparent in 4- or 5-day-old youngs. From these bases, it is obvious that the facial nerve elements related to sucking are firstly developed at birth and that the differentiation of the trigeminal nerve elements related to biting is rapidly accelerated after birth.
Choriocapillaris Regeneration in the Rabbit: A Study with Vascular Casts
Authors: Korte Gary E. , Pua Florence
Published: July 2008

Vascular casts were made of the choriocapillaris (CC) of rabbits that received sodium iodate intravenously 6–28 days prior to examination, in order to augment studies of CC regeneration in sectioned material. Regeneration of CC was evident 6 days after administration of iodate where zones of spared CC bordered zones of atrophic CC. Venular as well as capillary sprouts created foci of regenerating CC at this border. These foci subsequently enlarged by continued capillary branching and extension, and joined with adjacent foci to create an extended capillary plexus similar to mature CC. The observations corroborate those obtained in sectioned material as regards the geography of the CC response and the origins of new CC during the sodium iodate retinopathy, and provide new information on the way in which CC regenerates.
Appearance and Ultrastructure of Intranuclear Crystalloids in Tendon Fibroblasts Induced by an Anabolic Steroid Hormone in the Mouse
Authors: Michna Horst
Published: July 2008

The appearance of intranuclear crystalloid formations in tendon fibroblasts is described during enhanced protein synthesis. The enhanced protein synthesis was induced by an anabolic steroid hormone. One type of these crystalloids consists of closely packed bundles of filaments, 8–10 mm in diameter arranged in parallel.The other type of intranuclear crystalloids possesses an architecture similar to honeycomb pattern. Both of these paracrystalloid nuclear inclusions seem to be an indicator for an extremely enhanced protein synthesis in these cells after the administration of anabolic steroid hormones.Their numerous descriptions in the literature on hypertrophic or precancerously modified tissues and their increased occurrence under pathological influences both point to this explanation. In this way we now possess for the first time a model for experimentation on intranuclear crystalloids of tendon fibroblasts.
Relations of the Soft Structures of the Posterior Mediastinum in the Scoliotic Spine
Authors: Nathan H.
Published: July 2008

In 20 dissections of scoliotic cadavers, the changes of the structures in the posterior mediastinum in relation to the spine were found to be as follows. The aorta persistently followed and adhered to the abnormal curves of the spine. The azygos vein and the thoracic duct followed the aorta closely in its changes. The sympathetic trunk and the greater splanchnic nerves likewise followed the changes in the curvature of the scoliotic spine, but they were often disturbed in their course by vertebral osteophytes and by hyperostoses due to arthritis of the costovertebral joints. The esophagus preserved its normal straight course, unaffected by the scoliotic curves.
Histochemical Characteristics of the Basement Membranes of the Parietal Podocytes in the Rabbit Kidney
Authors: Ros Ma Angeles , Ojeda José L. , García-Porrero Juan A.
Published: July 2008

The patterns of silver affinity and following treatment with guanidine were studied in the basement membrane produced by parietal podocytes induced by corticoids in newborn rabbits. The goal of this study was to analyze the role of the different cell types of the renal corpuscle in the determination of the histochemical characteristics of the glomerular basement membrane (GBM). Jones’ method shows that while the GBM exhibited silver affinity only after periodic-acid oxidation, the basement membrane of parietal podocytes exhibits the same histochemical characteristics as the normal parietal basement membrane, appearing deep black both after periodic-acid or permanganate oxidation and after elastase or lysozyme digestions. Since the treatment with guanidine shows that the basement membrane of the parietal podocytes lacks the endothelial component typical of the GBM, it may be suggested that the special resistance to silver impregnation exhibited by the basement membrane after permanganate oxidation or after different enzymatic digestions is due to its endothelial component.
Cerebral Venous Sinuses: Anatomical Variants or Thrombosis?
Authors: Zouaoui A. , Hidden G.
Published: July 2008

Anatomical variations of the posterosuperior dural venous sinuses and, in particular, the absence or hypoplasia of one of them has been described in several studies. However, no recent detailed analysis on the subject exists. Cerebral venous thrombosis is quite often evoked, although rarely confirmed, when the physician is faced with patients having various neurological problems. In fact, for a number of cases the image interpreted as thrombosis is nothing but the total or partial absence of a dural sinus. It was considered of interest to undertake an anatomical study in order to define these variations. The results of anatomoradiological investigations of 70 fresh cadavers were compared to those obtained by angiographic examination of 100 patients not suffering from any kind of venous pathology (patients explored angiographically for glioma, meningioma or aneurysm). Our conclusions and a review of the embryology literature enabled us to demonstrate that a number of radiological findings, quite often considered pathognomonic of venous thrombosis (i.e. ‘delta sign’), are in fact the result of anatomical variations.
Talar Articular Facets (Facies articulares talares) in Human Calcanei
Authors: Campos Forriol , Pellico Gomez
Published: July 2008

The variations of the talar articular facets in 176 calcanei were studied and classified. Three types were considered: type A = calcanei with two articular facets for the talar head, with four subtypes; type B = calcanei with one articular facet for the talar head, and two subtypes, and type C = unique articular facies in the superior surface of the calcaneus for the talus. We found 53% (94 cases) type B calcanei and 46% (82 cases) type A calcanei. No calcanei of type C were seen.
Influence of Testosterone on the Development of the Ischiocavernosus Muscle of the Rat
Authors: Vercelli A. , Cracco C.
Published: July 2008

The mean area of the neuromuscular endplates and the acetylcholinesterase (AChE) activity at the myotendinous junction of the ischiocavernosus muscle were studied in normal, castrated and testosterone-treated castrated Wistar rats by the Koelle method. The mean endplate area was found to be smaller in castrated rats, compared to normal ones (p < 0.001), while testosterone treatment restored its normal size (0.8 > p > 0.7). The terminal AChE activity in castrated rats was as strong and spread as in juvenile ones, while it was almost absent in normal and in testosterone-treated castrated rats. The same parameters were examined in the tibialis anterior muscle of the same rats, chosen as a specimen of ‘nonhormone-dependent’ muscle, without finding any difference among the single groups.
Die Radix lateralis des Nervus ulnaris
Authors: Fuss Franz Konstantin
Published: July 2008

In 158 brachial plexuses the origin of the fibers of the ulnar nerve – whether only from the medial or also from the lateral fascicle – was investigated. A lateral root was found in 56%. This lateral root may either be accompanied by fibers of the median nerve (type 1) or may run separately (type 2). Where this root crosses the medial root of the median nerve, either a small minority of fibers of the latter nerve may run behind the ulnar fibers (type a) or all median fibers are in front of them (type b). Considering the relation 56:44% between ulnar nerves with and without a lateral root both possibilities have to be considered as normal variations, none as a variety. In analogy to the term ‘median loop’ the term ‘ulnaris loop’ is suggested for specimens with a lateral root.
Distribution of Different Fiber Types in Whole Cross-Sections of Human Platysma
Authors: Dittert Dag Daniel , Bardosi Attila
Published: July 2008

Analysis of cryostat cross-sections of the entire platysma muscle from human autopsies revealed enzyme histochemical and morphometric differences between normal human limb and facial muscles. The mean diameter of platysma fibers was about 50% of that of normal limb muscle fibers. Fiber type diameter increased from the medial to the lateral parts of the platysma. A variability coefficient of 356 indicated great variation in fiber caliber, with many fibers of 10 µm and less. Type I fibers showed an increase in density from the medial to the lateral parts of the muscle. The arrangement of histochemical fiber types was irregular with a tendency to form fiber type groupings.
Morphometric Analysis of Gap Junctions in Rat Myocardium after Hyperkalemia
Authors: Scheuermann Dietrich W. , De Maziére Ann M.G.L. , Aertgeerts Philip A.P.M.
Published: July 2008

The effect of membrane depolarization was investigated on gap junctions from isolated rat hearts perfused with a modified Krebs-Henseleit solution containing 16 mM K+. After freeze-fracturing, the configuration of the junctional particles in the ventricular myocardium was analysed by measurements of connexon densities and centre-to-centre distances between neighbouring particles. Both in control and hyperkalemic tissue, the gap junctions occur on the intercalated discs as round or oval aggregates of connexons which are closely and regularly packed in small, criss-cross-oriented arrays separated by particle-free aisles. Within the arrays, the mean (± SD) centre-to-centre distances between particles from control and hyperkalemic tissue, i.e. 9.17 ± 1.52 and 9.15 ± 1.51 mm, respectively, are not significantly different. Similarly, comparison of particle densities after control and high-K+ perfusion, i.e. 8,490 ± 600 and 8,420 ± 620 particles/µm2, respectively, reveals no difference in the proportion of the particle arrays to the empty aisles. The apparently unaltered gap junctional morphology after depolarization of the sarcolemma by high-K+ perfusion provides support for the electrophysiological finding that the conductance of cardiac gap junctions is insensitive to membrane potential.
The Preputial Gland of the Japanese Serow Capricornis crispus: infrastructure and Lectin Histochemistry
Authors: Atoji Yasuro , Suzuki Yoshitaka , Sugimura Makoto
Published: July 2008

Preputial glands of the Japanese serow were found to consist of the modified sebaceous gland and apo-crine gland in both sexes. In the modified sebaceous gland, cells transformed gradually toward the lumen from plentiful cytoplasm to a sponge-like network. Lipid droplets were observed in mitochondria of differentiating cells. By lectin histochemistry, differentiating cells were stained with Arachis hypogaea (PNA), Triticum vulgaris (WGA) and Canavalia ensiformis (Con A) lectins, while secretory cells of the apocrine gland revealed various stainings with PNA, Glycine max, Dolichos biflorus, WGA and Con A lectins. These findings suggest that glycoconjugates may have an active function in the preputial gland.
Population of the Diaphragm by Mast Cells in Growing Rats
Authors: Abood Enam A. , Jones Marilyn M.
Published: July 2008

The mast cell content of the diaphragm of the rat was examined using electron microscopy, and using light microscopy in material stained with Alcian blue. The concentration and diameters of the mast cells were estimated in animals at regular time intervals from 16 days gestation to 14 weeks of age and compared to the mast cell content of muscles of the calf and anterior abdominal wall. The results were discussed in relation to the origin of mast cells. It was proposed that if mast cells develop in haemopoietic sites that they may populate adjacent tissues by migrating within the connective-tissue spaces.
Histochemical Localization of Calcium in the Enamel Organ of Rat Incisors in Early-Stage Amelogenesis
Authors: Takano Yoshiro , Matsuo Saburou , Wakisaka Satoshi , Ichikawa Hiroyuki , Nishikawa Shinji , Akai Michio
Published: July 2008

The localization of calcium in the enamel organ of rapidly frozen, freeze-substituted rat incisors in early-stage amelogenesis was examined by a histochemical calcium-staining method. In secretory ameloblasts, glyoxal bis(2-hydroxyanil) (GBHA) staining revealed intense red reations in mitochondria and tubulovesicular structures located throughout the cytoplasm, while no reaction was seen in the nucleus and cytosol, nor along the plasma membranes of the respective cells. No significant GBHA reaction was observed in the intercellular compartment and other cells of the enamel organ. Some granular reactions were localized in the cells of the adjacent connective tissue. Control tests confirmed the specificity of GBHA reactions for calcium. Thus, the present observations provide histochemical evidence indicating an exclusive localization of calcium in mitochondria and tubulovesicular structures of the secretory ameloblast, and support their contributions to the translocation of calcium from the proximal to the distal pole of the cytoplasm.