bluuebunny/crossref_metadata_2025 huggingface dataset:
Roentgen Stereophotogrammetric Analysis of Growth at Cranial Vault Sutures in the Rabbit
Authors: Alberius Per , Selvik Goran
Published: July 2008

Biometric characterization of rabbit cranial vault bone separation was attempted to further elucidate sutural growth mechanisms. The internasal and frontonasal sutures, connected to the facial skeleton, were also investigated. 17 male New Zealand white rabbits were studied from age 4 to 21 weeks using roentgen stereophotogrammetry with tantalum implants. A uniform cranial growth pattern with successively decreasing rates was observed, as were different growth rates at the neurocranial bones relative to those of the facial skeleton. Anteroposterior length increase was due mainly to bone separation at the frontonasal suture. Growth at the sagittal suture was minimal. Minor rate fluctuations and compensatory rebounds after periods of reduced growth were continously observable. Small left-right differences within each individual were registered. Oscillations in growth rate across adjacent sutural areas and occasional negative growth values imply that bone separation at sutures demonstrates an alternating pattern of translations and rotations. The experimental data demonstrated the plasticity and variability of normal cranial vault growth.
Skull Morphogenesis and Growth: Hemodynamic Influence
Authors: Oudhof H.A.J. , van Doorenmaalen W.J.
Published: July 2008

In young dogs movements of cranial bones at the sutura sagittalis and sutura coronalis have been shown. They correlate with arterial blood flow. The connective fiber arrangement in the sutura, which has been found earlier, can be explained as being related to these movements.
Uterine Tube Microvascular Architecture after Oophorectomy in the Rabbit
Authors: Verco Christopher J. , Gannon Brendan J. , Jones Warren R.
Published: July 2008

4 adult female virgin rabbits underwent bilateral oophorectomy. 4 weeks later methylmethacrylate corrosion vascular casts of their uterine tubes were prepared. Scanning electron microscopy of the acrylic casts revealed a decrease in the size and number of the large ampullary plical and fimbrial veins which are normally characteristic of these regions. This observation suggests that the reported tubal dysfunction which follows oophorectomy may have a vascular component.
Histological Characteristics of the Lower Oesophageal Sphincter in the Cat
Authors: Clerc N.
Published: July 2008

The structure of the lower oesophageal sphincter (LOS) of the cat was investigated in comparison with that of the oesophagus. The following two main results were collected: (1) The muscularis mucosae of the lower oesophageal sphincter is much thicker than at oesophageal level (221 µm as compared with 17.8 µm on average). This thickening is particularly marked at the most prominent foldings of the mucosa. (2) Numerous annulo-spiral thin elastic fibres were found, in the circular layer of the LOS. These structures will coil spirally around muscular bundles and then wrap themselves around adjacent bundles so that they present an oblique orientation with regard to muscular fibres. Therefore it is concluded that in this species, the LOS is morphologically differentiated from the oesophagus.
Early Development of the Otocyst in an Exencephalic Mutant of the Mouse
Authors: Wilson Doris B.
Published: July 2008

Development of the otic anlage was studied by means of scanning electron microscopy in exencephalic loop-tail (Lp/Lp)embryos and in their normal (+/+; Lp/+)littermates at 8.5–9.5 days of gestation. In the abnormal embryos, the cells of the otic pit lack the rounded prominent surfaces and dense arrangement of microvilli which characterize the normal otic pit, and the overall configuration of the otic anlage is also distorted. The relatively early manifestation of abnormalities in the otic anlage of this mutant suggests that the defective neural tube may exert an influence as early as the otic placode stage, or that a common factor may simultaneously affect both otic and neural tube development in this mutant.
Volume Changes during Mitosis in Pancreatic Acinar Cells of the Rat
Authors: Abrahamsohn P.A , Sesso A.
Published: July 2008

The volume of interphasic and mitotic pancreatic acinar cells of 20-day-old rats was estimated by analysis of drawings from Araldite-embedded serial thick sections. Assuming the average interphase cell volume to be 100%, the volume of prophase cells was 145%, reaching a volume of 180% during anaphase. Postmitotic acinar cell volume was 74%.
Electron Microscopic and Histochemical Characterization of Intra-Arterial Cushions of the Rat and Porcine Uterine Vascular Bed
Authors: Heidger, Jr. Paul M. , Van Orden Diann E. , Farley Donna B.
Published: July 2008

Scanning and transmission electron microscopic studies, together with histochemical investigations, were conducted on rat and porcine intra-arterial cushions from the uterine vascular bed. In the rat, the fine structure of these cushions closely resembled that previously described in the rat kidney. The cushions were composed of modified smooth muscle, circularly disposed in an incomplete, raised band surrounding the entrance to arterial branches. These muscle cells projected as attenuated processes throughout the loosely organized, PAS-positive stroma, and established close contact with thin endothelial extensions projecting from the base of the surface endothelial cells. Scanning electron microscopic observations of furrows on the endothelial surface gave rise to the suggestion that such contacts might mediate muscular control of endothelial surface topology. In similar cushions from the pig uterine artery, the smooth muscle of the cushions was much more compactly organized, and was disposed radially, rather than circumferentially, within the cushion structure. The enzyme histochemical profile of porcine cushions did not differ appreciably from that of normal vascular smooth muscle and endothelium, suggesting the maintenance of a metabolic similarity with adjacent tissues. These studies clarify the fine-structural basis for recently reported contraction and relaxation of uterine artery cushions during ischemia and perfusion of the rat uterine vascular bed, and thus, for their functional role in the regulation of uterine vascular flow.
Number and Distribution of Ganglion Cells in the Vallate Papilla of Adult Human
Authors: Ferrell Fay , Tsuetaki Tracy
Published: July 2008

We examined the number and distribution of ganglion cells within a vallate papilla from a healthy human adult. The vast majority of cell bodies were located near the base of the papilla, clustered in the central portion of its core immediately above underlying muscles and von Ebner’s glands. Neurons appeared to be of one morphological type with ovoid cell bodies and spherical nuclei. The possible functional significance of their presence in invaginated or trench-containing gustatory papillae is discussed.
Stellate Cells in the Intima of Human Aorta
Authors: Krushinsky A.V. , Orekhov A.N. , Smirnov V.N.
Published: July 2008

Cells isolated from the fixed human aorta by alkaline dissociation have been studied. Cellular content of normal and atherosclerotic intima is described. Special attention is given to stellate cells that were found in large quantities in all analyzed samples. It is found that in the fatty streak stellate cells are localized nearest to the endothelium but they have no definite localization in the fibrous plaque. In unaffected intima, stellate cells are diffusely localized, and often prevail over other cell types.
Light and Electron Microscopy of Cells in Pig Colostrum, Milk and Involution Secretion
Authors: Lee C.S. , McCauley I. , Hartman P.E.
Published: July 2008

Cells in pig colostrum, milk and involution secretion were identified using light and electron microscopy. Cell types identified were neutrophils, macrophages, epithelial cells, eosinophils and lymphocytes. The neutrophils predominated in colostrum and involution secretion, whereas in milk it was the epithelial cell. Macrophages and lymphocytes were present throughout lactation and so too were eosinophils which were always present in lower concentrations. Both neutrophils and macrophages were seen with phagocytic vacuoles containing either lipid, casein or cellular debris. The possible roles played by the phagocytic and lymphoid cells in the protection of the mammary gland of the sow and the gut of the neonate from pathogenic microorganisms is discussed.
Effects of Neonatal Ovariectomy on the Ultrastructure of Gonadotrophs in Female Rats
Authors: Shiino Masataka , Yamauchi Koh-en
Published: July 2008

In order to investigate if castration cells or hypertrophic gonadotrophs are induced by ovariectomy at birth, neonatal female rats were ovariectomized within 12 h after birth and the pituitary cells were examined when the rats were 15 days of age by means of immunocytochemistry and electron microscopy. Hypertrophic gonadotrophs were present in the anterior pituitary glands of these young rats. However, when estradiol was injected on alternate days, beginning on the 5th day after birth, this castration response in the pituitary was markedly suppressed. This morphological evidence confirms physiological results previously reported that a feedback interaction between the ovary and the hypothalamo-adenohypophysial system is functional in the early days of life.
Postnatal Development of Sarcolemmal Invaginations in Right Atrial Myocardium of the Rat
Authors: Ferguson D.G. , Leeson T.S.
Published: July 2008

Postnatal development of the sarcolemmal invaginations of right atrial cells of the rat has been studied using standard fixation combined with tannic acid mordanting. T tubules were seen to form at Z lines as simple tubular invaginations starting at the 14th postnatal day. T tubules were present in most cells by the 18th postnatal day but, as in the adult, were restricted to peripheral regions. Also, between the 16th and 18th postnatal day a proliferation of caveolae was seen, both as single vesicles and as complexes with up to a dozen caveolae sharing the same neck. The caveolar complexes persisted in the adult and did not seem to contribute significantly to the formation of the T tubules. Dyadic couplings were seen to become more abundant as T tubules and caveolae proliferated. These findings are discussed in relation to transsarcolemmal Ca2+ movements and excitation-contraction coupling during postnatal development.
Study of Mandibular Shape in the Mouse
Authors: Lavelle Christopher L.B.
Published: July 2008

Mandibular shape was compared by the technique of medial axis transformation between four inbred strains of mice fed upon ‘hard’ and ‘soft’ diets. Multivariate analysis of component medial axis lengths showed the interstrain contrasts to be slightly greater between animals maintained on ‘hard’ as opposed to ‘soft’ diets. The mandibular shape contrasts primarily reflected differences of the ramus compared with the corpus, although the reasons for such changes have yet to be fully investigated.
Appendix Epididymidis and Aberrant Ductules of the Bull: Light-Microscopic and Ultrastructural Study
Authors: Goyal Hari Om
Published: July 2008

The appendix epididymidis and aberrant ductules possessed similar morphological characteristics. The epithelium was 31 ± 3 µm in height and consisted primarily of ciliated and nonciliated cells, although a few lymphocytes were also present. The ultrastructure of major cell types showed most cell organelles in their cytoplasm. However, these organelles were poorly developed, suggesting that neither cell type performed either a secretory or an absorptive function. Although the vestigial organs and ductuli efferentes were similar in epithelial height and epithelial cell types, there were important morphological differences that were reliably used to differentiate between the two. First, the luminal diameter was significantly smaller in the vestigial organs (60 ± 12 vs. 146 ± 44 µm in the ductuli efferentes). Second, the nonciliated cells of the vestigial organs, unlike those of the ductuli efferentes, lacked both dense granules and vacuoles in the cytoplasm. Finally, the tubular cross-sections of the vestigial organs were closely packed and were located at the tip of the caput epididymidis in the case of the appendix epididymidis, and between the lobules of the ductuli efferentes in the case of the aberrant ductules.
Alterations in Protein and Mineral Contents of Rat Skull Bones, Evoked by Different Protein Levels of the Diet
Authors: Pucciarelli Héctor M. , Oyhenart Evelia E. , Muñe María C.
Published: July 2008

Holtzman rats of both sexes were fed one of the following semisynthetic diets: 25% protein (control), 10% protein (slight malnutrition), 5% protein (medium malnutrition), and 2% protein (severe malnutrition). The skulls were cleaned and disarticulated with papain; they were defatted, dried, and the total weight (Tw) of each bone was determined. A gravimetric method of estimating bone protein-mineral ratio was performed. Following a decalcification with EDTA, the protein matrix was weighed (PMw). A protein-mineral index (PMI) was defined as: PMI = 100 (Tw-PMw)/Tw. The nutritional deficiencies imposed affected the protein and/or mineral contents of the bones according to three different patterns. The first pattern was followed by the bones of the vault and the facial region. The second one included the basicranial bones. The third one comprised the incisors. These patterns were associated with the histogenetic characteristics of the bones and teeth. A relationship between these findings and previously ascertained functional craniofacial variations in malnourished rats was found. From the differential behavior of the base, the vault, the masticatory apparatus and the incisors, it was inferred that each of these functional cranial components reacted to the experimentally unbalanced nutrition, according to a specific kind of adaptive mechanism.
Effects of Experimental Hyperadrenocorticism on the Growth of the Femur and Tibia in Normal and Bipedal Rats
Authors: Simon M.R.
Published: July 2008

Daily subcutaneous injections of glucocorticoid preparations have been shown to produce clinical signs of hyperadrenocorticism which resulted in interference with the growth of rats, shown by measurements both of body weight and of the length of long bones. The purpose of this study was to see if increased, intermittent, compressive forces, produced by experimental bipedalism, would mitigate the negative effects of cortisone injections on long bone growth and if there would be a difference in reaction between male and female rats. Male and female Sprague-Dawley rats were used for control, cortisone-injected, and cortisone-injected plus bipedal groups. Experimental bipedalism was produced at 10 days of age; cortisone injections began at 30 days of age; all animals were sacrificed at 65 days of age. Tibial and femoral lengths were measured. The results do not support the hypothesis that bipedalism can be instrumental in mitigating the effects of hyperadrenocorticism on hindlimb long bone growth.
Changes Induced by Apamin from Bee Venom on Differentiated Mouse Neuroblastoma Cells in Culture
Authors: Spoerri P.E.
Published: July 2008

The minor active component of bee venom was applied to mouse neuroblastoma cultures. The cytological changes observed are reported. After 8–10 h of incubation with 5 µg/ml of apamin in the culture medium, considerable retractions of the processes are apparent. Electron microscopically, the alterations seen are predominantly found in the subcellular organelles. The peculiar configuration of the endoplasmic reticulum (ER) is striking. Concentric whorls of cisternae seem to engulf the remaining ground substance. Following a 24-hour incubation with 5 µg/ml of apamin, the cell membrane disintegrates. A deeply infolded nucleus, vacuoles and remnants of cell organelles are present. The previously intact synapses are totally degenerated. Similar experiments using lower concentrations of apamin do not depict any apparent changes either light or electron microscopically.
Stereological-Ultrastructural Study of Pancreatic B Cells in Metabolic Alkalosis
Authors: Semino María C. , Rebolledo Oscar R. , Gómez Dumm César L.A. , Gagliardino Juan J.
Published: July 2008

The secretion of insulin in response to glucose and the changes in the B cell at the ultrastructural level were studied in rat pancreas perfused at pH 7.4 and 7.8 with different concentrations of glucose. Raising the extracellular pH from 7.4 to 7.8 significantly inhibits glucose-induced insulin secretion. Coincidently, morphometric studies showed significant evidences of low secretory activity in B cells from pancreas submitted to high glucose stimulation under alkalosis, namely lower number of emiocytotic figures and microtubules as well as a decrease in the volume density of the granular endoplasmic reticulum and the Golgi complex. On the other hand, a significant increment in the number of images of granulolysis was also demonstrated. These secretory and ultrastructural results confirm the inhibitory effect of pH 7.8 upon B cell secretory activity induced by glucose. Moreover, they lend further support to the role of intracellular hormone degradation as a regulator of B cell insulin content.
The Association of a Retroesophageal Right Subclavian Artery, a Right-Sided Terminating Thoracic Duct, and a Left Vertebral Artery of Aortic Origin: Anatomical and Clinical Considerations
Authors: Nathan Hilel , Seidel Michael R.
Published: July 2008

The findings in a cadaver demonstrated: (a) an aberrant retroesophageal right subclavian artery (RRSA); (b) a thoracic duct (Th.d.) terminating at the junction of the right internal jugular and subclavian veins (‘venous angle’), and (c) a left vertebral artery (LVA) of aortic origin. The origin of the RRSA from the aortic arch was distal and medial to the left subclavian artery and it reached the upper extremity by crossing posterior to the esophagus. The Th.d. ran a normal retroesophageal course in the mediastinum, until it was intercepted by the anomalous subclavian artery. At this level the Th.d. was deflected towards the right and, accompanied by the anomalous artery, reached the right venous angle. The LVA arose from the aortic arch between the left common carotid and the left subclavian arteries, and ascended to the transverse foramen of C6. The practical importance of associations in general is discussed, and the special diagnostic and surgical significance of the RRSA and Th.d. is stressed.
Taste Bud Papillae on the Retromolar Mucosa of the Rat, Mouse and Golden Hamster
Authors: Iida M. , Yoshioka I. , Muto H.
Published: July 2008

The retromolar mucosa of the rat, mouse and golden hamster was observed by light and scanning electron microscopy. Numerous taste bud papillae, each of which formed a low round eminence containing one to several taste buds, were present in the posterior region of the retromolar mucosa, and were especially concentrated in the vicinity of the orifices of the molar glands. This topographical coincidence suggests that the retromolar mucosa of these animals has a functional role as a taste organ. Microridges, arranged in various patterns and small pits, were observed on the surface of the keratinized epithelium of the rat and mouse retromolar mucosa. It appears that the development of numerous microridges is adapted for varied stimuli in the oral cavity.
Asymmetries in Body Part Size, Mobility, and Usage
Authors: Koff Elissa , Borod Joan C. , White Betsy , Nicholas Marjorie
Published: July 2008

Asymmetries in structure (size) and function (usage or mobility) for the upper and lower face, hands, and feet were investigated in 42 left- and right-handed male and female college students. Size measurements were taken from photographs, mobility was rated from videotapes, and usage was assessed by questionnaire. Size asymmetries were typical, and independent of handedness, but were not consistent across body parts; usage asymmetries varied as a function of handedness. No systematic relationships were found between structure and function.
Zur Morphologie der Ampulla ductus deferentis von Kaninchen
Authors: Kunkelmann Hiltrud , Kühnel Wolfgang
Published: July 2008

The structure of the ampulla ductus deferentis of adult rabbits was studied by light-, transmission- and scanning-electron microscopy. The ampulla consists of a network of diverticles surrounding the central lumen. The diverticles are connected with each other and with the central lumen by oval or round openings. After ejaculation diverticles are usually empty. However, some diverticles were filled with spermatozoa only at sexual rest. The epithelial cells contain an abundant Golgi apparatus, which is organized as a system of closely packed flattened cisternae sometimes being in close connection to lipid droplets and lysosomes. The plasma membrane forms long microvilli-like processes and sometimes vesiculated spherical bodies, swollen cellular apices and protuberances apparently being pinched off.
Crystal Growth in Calcifying Fronts during Dentinogenesis
Authors: Hayashi Y.
Published: July 2008

Additional dentinogenesis in calcifying fronts of permanent tooth germs in kittens was examined using a transmission electron microscope. The irregular island-like structures were observed in calcifying fronts. These islands, increased in size, formed the coalescence. Pairs of fine crystals ran parallel in the marginal zone of these islands. At the inner part of the islands, long and wide crystals were abundant. Furthermore, a three-dimensional visualization of crystals revealed that dentin crystals were of needle-like shape. These findings suggest that pairs of fine, needle-like crystals first appear and additional calcification progresses due to fusions between fine crystals, and maturation in crystallization occurs along the long axis following these fusions.
Parafollicular Cells of the Rat Thyroid Gland after Treatment with Vitamin D
Authors: Zabel M.
Published: July 2008

Ultrastructural studies on rat thyroid demonstrated two types of secretory granules in parafollicular cells. In control animals were significantly more frequent strong osmophilic granules of approximately 130 nm in diameter than weak osmophilic granules of approximately 200 nm in diameter. Number and ratio of granules of the two types varied greatly in parafollicular cells. Administration of vitamin D3 induced a depletion of strong osmophilic granule number while the larger, weak osmophilic secretory granules continued to be stored. Immunocytochemical tests detected calcitonin in the small, strong osmophilic granules and showed that calcitonin content decreased after vitamin D3 administration. The obtained results suggest that the smaller, strong osmophilic granules contain calcitonin only, while the larger, weak osmophilic ones may contain somatostatin only.
Tracer, Cytochemical, and Freeze-fracture Study on the Mechanisms whereby Secretory Ameloblasts Absorb Exogeneous Proteins
Authors: Sasaki T.
Published: July 2008

To investigate the mechanisms whereby secretory ameloblasts absorb and digest exogenous proteins, rat incisors were examined by means of the tracer, cytochemical, and freeze-fracture methods. In the tracer experiment, intravenously injected horseradish peroxidase (HRP) rapidly penetrated into the intercellular spaces of the ameloblast layer through the proximal junctional complexes and further diffused beyond the distal junctional complexes. Freeze-fracture replicas indicated various spaces among the strands of the distal tight junctional complex, which nonetheless completely sealed the cell. The HRP was taken into the cytoplasm from Tomes’ process by large coated vesicles and tubulovesicular structures. In replica images, many small pits on the P face and corresponding bumps on the E face of the cell membranes were observed in Tomes’ process. These pits and bumps are thought to correspond to coated pits representing initial images of micropinocytosis in thin sections. Following absorption, the HRP migrated into endocytic vacuoles or large phagosomes in the supranuclear cytoplasm. Both structures were positive for acid phosphatase reaction and are, therefore, taken to represent phagolysosomes. These results suggest that the secretory ameloblast is able to absorb and digest enamel protein actively from the developing matrix.
Pericapillary Spongy Sheaths in the Human Spleen
Authors: Brozman Miroslav
Published: July 2008

Antisera to extracts of human hyaline cartilage allow distinct visualization of extracellular structures of adventitial sheaths around arterial capillaries in the red pulp and marginal zone in the human spleen. These pericapillary sheaths have a prominently spongy character indicating their essential filter function. In childhood they are most marked. In premature and stillborn infants they sometimes occupy whole stretches of pulp cords, whereas in old age they are frequently diminished to small formations lacking a distinctly spongy structure.
Histamine Disposition in Endothelial Specific Granules of the Toad Aorta
Authors: Fujimoto Sunao , Yamamoto Koji , Ueda Hiroshi , Hamasaki Kunshige , Nomiyama Tomohiko
Published: July 2008

High-performance liquid chromatography revealed that toad aorta delivered appreciable concentrations of histamine into the perfusate when perfused by Ringer’s solution containing the histamine liberator. Electron micrographs of this vessel after the perfusion showed an expulsion of the endothelial specific granules into the vascular lumen. These results support to our previous hypothesis that the granules are a reservoir site of histamine and might take an important role in the regulation of vascular tone.
Ultrastructural Study on Oogenesis in Shrews (Neomys fodiens, Sorex araneus)
Authors: Kress Annetrudi
Published: July 2008

The ultrastructure of early follicular oocytes is described. Among the differentiating organelles marked development of endoplasmic reticulum, often in close contact with mitochondria, is especially conspicuous. In addition, the dilatation of mitochondria, the accumulation of dense granular material and the formation of multivesicular bodies are discussed.
Arcus paracolicus
Authors: Vandamme J.P.J. , Bonte J.
Published: July 2008

The paracolic arcade is the most important vessel for the blood supply of the colon. It can be compared with the felly of a wheel, whose spokes are the colic arteries. It is the immediate source of the colic supply and the most important way for collateral circulation between the colic arteries and even between the superior and inferior mesenteric arteries.
Effects of Epinephrine Treatment on the Rat Parathyroid Gland, with Special Reference to the Frequency of Storage Granules
Authors: Setoguti Takao , Inoue Yasuhisa , Shin Masashi , Matsumura Hidekatsu
Published: July 2008

Effects of epinephrine treatment on the rat parathyroid gland were studied morphologically. The mean number of storage granules per cell section (NSG) was rapidly decreased as early as 5 min after an injection of epinephrine and seemed to reach a minimum between 5 and 30 min. During this period, serum calcium levels (SCL) gradually rose and reached a maximum at 30 min. The ultrastructure of chief cells in these epinephrine-injected rats showed no marked difference as compared with that in control rats. In slightly hypocalcemic rats, induced previously by 2% EDTA-treatment, NSG was more rapidly decreased. It was suggested that storage granules may be released promptly by epinephrine treatments in spite of high SCL and that they are more promptly released under hypocalcemia.
Fatty Involution of Bone Marrow in Rabbits
Authors: Bigelow Carolyn L. , Tavassoli Mehdi
Published: July 2008

The developmental pattern of red and yellow bone marrow was studied in rabbits of different ages from newborn to 6 months of age. At birth no adipose cells were seen in any of the marrow cavities. Most bones were still developing and marrow cavities were relatively limited. Nonetheless a distinct difference in the cellularity of marrow in the trunk versus limb bones was noted, the latter being significantly less cellular. Adipose cells began to develop at 2 weeks of age and proceeded so that the adult pattern of red and yellow marrow was fully established by 4 months. The development of adipose cells occurred in both trunk and limb bones; the magnitude of the process, however, was considerably greater in the limb bones. Adipocyte precursors may be present in the marrow at birth with a differential distribution in the areas of prospective red and yellow marrow. Thus, fatty involution of marrow appears to be a programmed developmental event.
Identification of Eight Types of Synapses in the Pallidum externum and internum in Squirrel Monkey (Saimiri sciureus)
Authors: Hassler Rolf , Chung Young-Wha
Published: July 2008

The electron microscopic study of the neuronal structures of the pallidum externum (Pa.e) and internum (Pa.i) in squirrel monkey (Saimiri sciureus) has revealed in both segments a frequent large type of nerve cell and a rare small one, probably an interneuron. With respect to the small cells, only one axosomatic synapse inserts on the slender rim of cytoplasm; the clear nucleus is always invaginated and contains a small nucleolus. Eight types of synapses can be differentiated in Pa.e and Pa.i. The axodendritic type I P with pleomorphic vesicles and an inconspicuous symmetric contact to a central dendrite, make up 65% of all synapses in Pa.e and 79% in Pa.i. These synapses are commonly arranged in a rosette pattern around the dendrite. Two subtypes of the type I P are found in both segments – the one with invaginated boutons (subtype I Piv) and the other (subtype I Pol) oligovesicular. The type III SR synapses are characterized by small round or slightly oval vesicles and a strongly asymmetric contact (12% in Pa.e and 8.1% in Pa.i). The predominantly axosomatic type II EF synapses are characterized by elongated vesicles as well as by encapsulation in thin astrocytic processes (5% in Pa.e, 8.5% in Pa.i). The boutons of type IV Sph characterized by large uniformly spherical vesicles undergo symmetric synaptic contacts (in Pa.e 6% and in Pa.i 0.5%). The type V Osl stiletto-shaped bouton with ovoid vesicles undergoes a symmetric contact with a dendrite (in Pa.e 5% and in Pa.i 1.1%). Two types of dendrodendritic and dendrosomatic synapses are found: the type VI DE containing sparsely distributed elongated vesicles suspended on neurofilaments, undergoing a symmetric contact, and the type VII DC with clustering mostly round vesicles near the presynaptic component of the asymmetric contact. The rare axodendritic type VIII My arising from a myelinated axon, exhibits small elongated vesicles and symmetric contact. The synaptic types I, III, IV, and VI are similar to the same types in the substantia nigra, whereas types II, V and VII resemble the equivalent types in the motor thalamic VA and ventro-oralis anterior nuclei.
The Irreversible Ischaemic Lesion of Human Myocardium
Authors: Ludatscher R.M. , Hashmonai M. , Peleg H.
Published: July 2008

The autolytic ultrastructural changes of the human myocardium were studied in 25 specimens taken 30 min to 18 h post mortem. Damage to the mitochondrial membranes and the appearance of mitochondrial armorphous densities characterized the irreversible lesions of the autolytic myocardium. The development of these changes was observed in consecutive samples. At 30 min, few small densities were noticed inconsistently, and they progressively increased in size and number over the next 90 min. The development of these changes was unrelated to the cause of death. Comparison of the ischaemic heart lesions of animals with those of humans shows a similarity of the mitochondrial amorphous densities. The best analogy was found to exist between the autolytic changes of the human myocardium and the irreversible ischaemic heart lesions of dogs.
Scanning Electron Microscopy of Exposed Surfaces of the Porcine Placenta
Authors: Dantzer Vibeke
Published: July 2008

The three-dimensional development of the separated parts of the porcine placenta from 9 Danish Landrace sows at gestational stages from 20 to 100 days was studied. After cautious separation of the allantochorion and the endometrium in a 1 mM buffered ethylenediaminetetraacetic acid solution, the separated parts were processed for scanning electron microscopy by routine methods. The macroscopic enlargement resulted from primary and secondary circular folds or plicae, which were permanent on the maternal side, whereas they were mainly non-permanent on the fetal side. The areolar placenta and interareolar placenta with formation of permanent microscopic folding on both sides were described. The observations of the separated parts yielded new information on the development of surface enlargement during gestation and revealed a hitherto unknown regular architecture of the endometrium by the formation of parallel primary ridges or rugae with secondary ridges or rugae at their sides subdividing the maternal troughs or fossae. This configuration on the maternal side explains the transformation of the regular chorionic ridges from the 63-day stage into bulbous protrusions at the 100-day stage. Based on these observations the precise terminology used above was proposed.
Implantation in the Rabbit: Ultrastructural Features of Nuclei Involved in Symplasm Formation
Authors: Segalen J. , Lescoat D. , Chambon Y.
Published: July 2008

Mitoses, direct division or cell fusion are observed during symplasm formation in the rabbit uterus epithelium. These phenomenon are examined through transmission electron-microscopic studies. Two types of direct division are described: (1) nuclear scission after folding of the membrane and (2) nuclear scission by invagination of the membrane. The existence of amitoses has long been contested in mammals; the present study tends to show that direct division is not an accidental karyorrhexis but is organized at the cellular level.
Influence of Experimental Liver Injury on Rat Blood and Alveolar Bone under Stress
Authors: Lassila Veijo , Virtanen Pauli
Published: July 2008

Experimental liver injury was induced to test rats with a daily injection of thioacetamide (ThAA). The doses used for intraperitoneal administrations were 50 mg/kg body weight. The loss of body weight in the 3-week test period was 15%. In the liver there was seen progressive changes which displayed cell necrosis and regeneration. The influence of ThAA on rat blood and serum was checked using standard biochemical assays consisting of the percentage of blood obtainable and the serum/blood ratio and analysis of serum alanine transferase, serum alkaline phosphatase, serum creatinine, and hydroxyproline in the acute, subacute, chronic, and necrotic stage of liver injury. With ThAA injections, the stimulated rate of glycosaminoglycan synthesis had its association to the serum calcium content. It decreased continuously as function of traumatization time. In the 3-week test period, histological findings show in the alveolar bone, around the teeth, when under occlusal stress and ThAA traumatization, the distinct decrease in osteoblastic activity and less osteoids indicating thus the decreased formation of new bone. Conspicuous osteoclastic resorption was also seen in the same area.
Le développement post-natal et les rapports du sinus maxillaire
Authors: Jovanović S. , Jeličić N. , Kargovska-Klisarova A.
Published: July 2008

In children, the maxillary sinus is pyramidal in shape. The apex of the pyramid looks forward, and the base looks backwards. The maxillary sinus has three walls – the superior, the medial and the inferior. The superior wall establishes a relationship with the infraorbital groove and the infraorbital canal during the 4th year. During the first months of life, the maxillary sinus has no relationships with the inferior nasal meatus. At about 6th year, the maxillary sinus is at the height of the floor of the nasal cavity and thus a close relationship is established with the inferior nasal meatus.
Relationship between the Physiological Cross-Section of the Human Jaw Muscles and Their Cross-Sectional Area in Computer Tomograms
Authors: Weijs W.A. , Hillen B.
Published: July 2008

Physiological cross-section (PCS) and cross-sectional area in computer tomograms made at right angles to the mean fibre direction were compared in the masseter, temporalis and pterygoid muscles of six human cadavers. PCS was determined as (1) total cross-section of teased fibre bundles (2) total fibre weight divided by mean fibre length. The two measures correlated strongly, but the first was always 25% lower than the second, irrespective of the muscle concerned. The cross-sections in the tomograms (SCS) were smaller than the PCS, except in the lateral pterygoid. In all muscles, a statistically significant correlation was found between SCS and PCS. The SCS can be used to predict PCS, with an error of 0.3–1.0 cm2. In our material, cross-sections were about 20% higher than reported in the literature. It is suggested, that this discrepancy is caused by the loss of natural teeth.
Quantitativ-histologische Untersuchungen des fetalen menschlichen Pankreas von stoffwechselgesunden Frauen und insulinabhängigen Diabetikerinnen
Authors: Hahn von Dorsche Herwig , Reiher Horst , Hahn Hans-Jürgen
Published: July 2008

Human fetal pancreases from nondiabetic (n = 26) and insulin-dependent diabetic women (n = 14) between the 13th and 26th week of pregnancy were investigated morphologically. There was in enhanced islet cell volume in fetuses from diabetic patients compared to those from nondiabetics, mainly caused by nesidioblastosis. This phenomenon could be caused by the metabolic state of the insulin-dependent diabetic patients. There were also single beta cells or groups of beta cells, which could be found between the exocrine pancreatic tissue, already at an early stage in pregnancy. It is assumed, that the nesidioblastosis in fetuses from diabetic women is caused by a continuous stimulation of the fetal endocrine pancreas during pregnancy. These results are in a good correlation to the in vitro results of the insulin secretion of human fetal pancreatic slices after incubation.
Topographical Distribution of Acetylcholinesterase in the Subfornical Organ of the Rat
Authors: Achaval Matilde , Schneider Felipe Luis
Published: July 2008

Acetylcholinesterase (AChE) activity in the rat subfornical organ (SFO) was determined by the Koelle and Friedenwald method. Coronal sections showed a homogeneous reaction in the rostral region, which adopted a ring-like form in the anteromedial zone and a horseshoe pattern in the posteromedial zone. In the latter, AChE-specific positive neurons had been observed clearly in our sections. In sagittal sections the enzymatic reaction was intense in the anterior subependymal zone and dorsal region, and it continued caudally to the hippocampal area. The enzymatic activity was absent in the central region of the anteromedial zone and the subependymal region of the posteromedial zone. In sagittal sections the reaction was strongly positive in the periphery of the organ and negative in the posteromedial zone, near the choroid plexuses. Thus, we have shown that each region of the SFO presents a particular distribution of the AChE activity, related in some cases to neurons and in others to nerve fibers.
Cell Proliferation in the Dog (Beagle) Ovary during Proestrus and Early Estrus
Authors: Spanel-Borowski Katharina , Thor-Wiedemann Sabine , Pilgrim Christoph
Published: July 2008

Cell proliferation in the ovaries of 5 Beagle dogs was studied by autoradiography after pulse labelling with (3H)-thymidine during different periods of proestrus and early estrus. Indices of labelling and of necrosis were determined for different follicle types grouped according to their stages of atresia. Cell proliferation became most obvious during early proestrus in antral and in Graafian follicles, and during the periovulatory period in preantral follicles. By contrast, low labelling indices appeared in all follicle types during the middle of proestrus. All follicle types demonstrated a continuous decrease in labelling from early to late atresia with the exception of the granulosal layer of antral follicles during the periovulatory period. While many necrotic granulosal cells were found in antral follicles during the first 6 days of proestrus, there were few during the periovulatory period. Even Graafian follicles displayed necrotic granulosal cells now and then. It may be concluded that (1) intact ovarian follicles can show subtle changes indicating the beginning of atresia, and (2) during the proliferative phase of a long estrous cycle cell replication in the ovary is characterized by two bursts at the beginning and at the end of this period.
Restoration of the Softness and Flexibility of Cadavers Preserved in Formalin
Authors: Tschernezky W.
Published: July 2008

Submerging parts of cadavers in a 5 % aqueous solution of glacial acetic acid eliminates the undesirable properties of formalin and formalin-containing fixatives such as the irritating and unpleasant smell of formalin and phenol. It also considerably softens the tissues, renders the articulations flexible and makes dissection much easier. No significant bone softening occurs if the process is stopped at a suitable time. Parts of the bodies softened in this way can be kept for years in 70% alcohol without any signs of a loss of flexibility or decomposition.
Microvascular Architecture of the Pregnant Rabbit Oviduct
Authors: Verco Christopher J. , Gannon Brendan J. , Jones Warren R.
Published: July 2008

Methyl-methacrylate vascular corrosion casts of the oviducts were prepared in 7 rabbits which were 2–3 weeks pregnant. Scanning electron microscopy of the acrylic casts revealed little change in tubal microvascular connections when compared with control oviducts. Venous distension in the isthmic subserosal venous plexus, ampullary subserosal vasculature and in the fimbrial core was substantially greater than that observed in controls. These changes are interpreted as indicating a sensitivity of tubal microvasculature to the increased levels of circulating placental hormones in pregnancy. The implications of this interpretation in the role of tubal microvasculature at the time of ovulation are discussed.
Immunocytochemical Study of the Gastroenteropancreatic Endocrine Cells of the Sheep
Authors: Calingasan Noel Y. , Kitamura Nobuo , Yamada Junzo , Oomori Yukio , Yamashita Tadayuki
Published: July 2008

The gastroenteropancreatic (GEP) endocrine cells of the sheep were studied immunocytochemically and their distribution and frequency were determined. Eleven types of endocrine cells were revealed. In the abomasum, somatostatin-, gastrin-, glucagon- and glicentin-immunoreactive cells were detected with the highest frequency in the pyloric region. In the small intestine, somatostatin-, gastrin-, CCK-, motilin-, neurotensin-, secretin-, substance P-, glucagon-, glicentin- and BPP-immunoreactive cells were found and were most numerous in the duodenum except for neurotensin-, glucagon- and glicentin-immunoreactive cells which were more concentrated in the ileum. In the large intestine, somatostatin-, substance P-, glucagon-, glicentin- and BPP-immunoreactive cells were localized with the last three cell types being more concentrated in the rectum. In the pancreas, somatostatin-, glucagon-, glicentin-, BPP- and insulin-immunoreactive cells predominated within the islets and were also scattered in the exocrine portion and rarely detected in duct epithelial cells. The differences between the distribution and frequency of the GEP endocrine cells of the sheep and those of monogastric species are discussed.
In vivo Bone Strain on the Dog Tibia during Locomotion
Authors: Bouvier Marianne , Hylander William L.
Published: July 2008

Rosette and single-element strain gauges were implanted on the tibia in 2 dogs and recordings were made during locomotion on a treadmill. At foot contact and during the swing phase of locomotion, bone strains were low and directions of the principal strains were variable. There was a large shift in the directions of the principal strains at the beginning of the stance phase and bone strains were considerably higher. Peak strain occurred midway through the stance phase. At that time, the maximum pπnicipal strain (tension) was directed upwards and anteriorly between 30 and 60° with respect to the long axis of the tibia. These bone strain patterns in the dog are similar to those found in sheep while both differ markedly from those found in humans.
Pancreas annulare in Human Embryos
Authors: Kirillova I.A. , Kulazhenko V.P. , Kulazhenko L.G. , Lazjuk G.I. , Novikova I.V.
Published: July 2008

2 cases of pancreas annulare with duodenal stenosis were found among 3,307 induced abortuses of 5–12 weeks where the pancreatoduodenal area was available for examination. This corresponds to a 0.06% incidence, greatly exceeds the occurrence of the anomaly in neonates and suggests partial prenatal elimination of embryos with pancreas annulare and duodenal stenosis. Microscopic examination of serialed embryonic sections gives evidence of (1) the origin of the ring from the ventral anlage; (2) the underdevelopment of the ring material, which later may cause fibrosis of the annulus, usually observed in neonates; (3) the origin of duodenal stenosis in case of pancreas annulare till 8 weeks of fetal life; (4) the development of such stenosis not only due to atrophy of duodenal segment, resulted from compression by the pancreatic ring, but also due to anomalous differentiation of intestinal segment, the cause of which may be the disturbance of morphogenetic correlations.
Contribution of the Superior Atrioventricular Cushion to the Left Ventricular Infundibulum
Authors: García-Peláez Isabel , Díaz-Góngora Gabriel , Arteaga Martinez Manuel
Published: July 2008

The role of the superior atrioventricular cushion in the normal development of the left ventricular infundibulum was experimentally studied in the chick embryo. 178 embryos at stages 19–24 of Hamburger and Hamilton were selectively labeled using gelatin-india ink; afterward embryos were reincubated until the mature heart stage, in which the final location of the labels was determined. In addition, anatomical microscopic studies were carried out on the chick embryo heart at different stages of the development. 91 embryos were obtained at the mature heart stage, 46 of which were normal. In 82,6% of these 46 embryos labels were found in the left ventricular infundibulum and were distributed in the following regions: (1) base of the free portion of the anteroseptal mitral leaflet (mitroaortic continuity); (2) the same region plus the left surface of the anterior basal portion of the ventricular septum, and (3) the left surface of the anterior basal portion of the ventricular septum. Anatomical microscopic studies showed that the superior atrioventricular cushion appears at stage 18, fusing with the inferior cushion at stage 28. Our results permit us to conclude that the superior atrioventricular cushion plays an important role in the normal development of the left ventricular infundibulum, and it contributes in the posterolateral and anteromedial wall formation.