bluuebunny/crossref_metadata_2025 huggingface dataset:
Quantitative studies on the mouse facial nerve trunk distal to the geniculate ganglion
Authors: Shimozawa Atsumi
Published: February 2009

A fiber count analysis was performed with the electron microscope on the facial nerve trunk distal to the geniculate ganglion in seven mice. On an average, 4,836 (93%) of the total nerve fibers (5,201) were myelinated and 328 (6.3%) unmyelinated. The large part of the nerve consisted mostly of large myelinated fibers (large-fiber group). The small part of the nerve consisted of small myelinated and unmyelinated fibers (small-fiber group). The fiber constitution of the small-fiber group in the nerve was more like that in the intermediate nerve than that of the small-fiber group in the motor root of the facial nerve. Thus, it is postulated that the nerve fibers of the small-fiber group in the facial nerve trunk distal to the geniculate ganglion may be derived from the intermediate nerve, and that the nerve fibers of the small-fiber group in the motor root of facial nerve may course to the greater petrosal nerve.
Re-evaluation of the colic irrigation from the superior mesenteric artery
Authors: Vandamme J.P.J. , Der Schuren Van
Published: February 2009

156 abdominal preparations were explored by arteriography, corrosion and dissection. The ileocolic artery is the most constant collateral of the superior mesenteric artery. It provides a ramus colicus which is often confused with a true arteria colica dextra. The a. colica dextra, arising on the superior mesenteric artery, is found in only 13% of the abdominal preparations. The PNA ‘a. colica media’ covers a system of individually varying vessels: a. colica media, common stem of r. anguli coli and r. coli transversi; a. anguli coli, a. coli transversi; a. colica sinistra accessoria and a. coli transversi accessoria. Both mesenteric arteries may be linked by an intermesenteric arch (12%).
Experimentally induced osteoarthrosis in the temporomandibular joint of the mouse
Authors: Silbermann Michael
Published: February 2009

(1) 6-week-old ICR mice were injected daily with pharmacologic doses of triamcinolone diacetate (1.5 mg/kg body weight) for 8 consecutive weeks. (2) The temporomandibular joint served as a model for histological and histochemical examinations concerning the effect of glucocorticoid hormone upon bone and cartilage. (3) Histochemical reactions indicated a large number of lipid droplets within the peripheral vasculature. (4) Histological examinations revealed pathologic features, indicative of primary osteoarthrosis.
Adaptive differences in the body proportions of large felids
Authors: Gonyea William J.
Published: February 2009

Body proportions of eight species of large felids were studied and the relationship between their morphology, habitat structure and habitat utilization was analyzed. Both Panthera onca and Neofelis nebulosa are exclusive forest dwellers (found exclusively in high densly structured habitats). These felids have the relatively shortest anterior limbs and lumbar spine. In addition, P. onca has the relatively shortest posterior limbs of the large felids, while the posterior limbs of N. nebulosa are relatively long when compared with those of P. onca which seems to be an adaptation for jumping. All large felids use the anterior limbs to make primary contact with their prey. In addition, the prey taken by the forest felids can exceed their own body weight. On the other hand, the cheetah is found in low structured habitats (savanna), and it has the relatively longest limbs and lumbar spine of the large felids. But the cheetah’s prey usually weigh less than its own body weight. The cheetah also employs a ‘rapid pursuit phase’ in hunting and is capable of overtaking its prey. The lion, however, was found to have the body proportions of a forest felid, yet it also resides in low structured habitats. It is postulated that the utilization of large prey by the lion limits the possibilities for morphological adaptations for speed. To increase hunting efficiency, reproductive success, and territorial defense on the plains, lions form prides.
The skin of the palms and soles of the marmosets (Callithrix jacchus and Callithrix penicillata)
Authors: Miraglia Tulio , da Costa Nery Jorge W , Guedes Maria Lúcia Costa
Published: February 2009

The structure and histochemistry of the palmar and plantar skin were studied in four adult male marmosets (two Callithrix jacchus and two Callithrix penicillata). In this skin there exist well-developed epidermal ridges, to which are attached one or two ducts of sweat glands. A thick stratum corneum can be seen in the epidermis, while a distinct stratum lucidum cannot be isolated from the other layers. The stratum granulosum is constituted by one or three layers of cells containing keratohyalin granules. Melanin granulations are mainly concentrated in the basal cells of the epidermal ridges. Dendritic melanocytes and amelanotic melanocytes containing alkaline phosphatase are found among the epidermal cells. Glycogen, UDPG-GT and phosphorylases are mainly present in the middle and lower Malpighian cells of the epidermal ridges. Alkaline phosphatase, ATPase, alanyl amino-peptidase and leucine aminopeptidase were absent in the epidermal cells. SDH, cytochrome oxidase, MAO and a certain number of NAD-dependent dehydrogenases (LDH, ADH, MDH, α-GPDH, β-OHBDH and GDH) showed a stronger reactivity in the basal cells and Malpighian layer. The NADP-dependent enzymes (G-6-PDH, 6-PGDH, β-aconistase and ICDH) were more reactive in the upper Malpighian layer and stratum granulosum. The stratum corneum showed some acid phosphatase and nonspecific esterase reactivity. The collagenous fibers intertwined with a small number of very thin elastic ones and a larger amount of reticular fibers run almost parallel to the epidermal ridges in the papillary body. In the reticular dermis some fibers are disposed transversely to the epidermal ridges. Meissner corpuscles reactive to butyrylcholinesterase, acetylcholinesterase, nonspecific esterase and G-6-PA are disposed at regular intervals and frequently at each side of the epidermal ridges. Pacinian corpuscles were found only in the hypodermis. The eccrine sweat glands contain glycogen, UDPG-GT and phosphorylase in their secretory, ductal and myoepithelial cells. The secretory part shows a uniform reactivity for every dehydrogenase because it contains
Odontometric study of African monkey teeth
Authors: Lavelle C.L.B.
Published: February 2009

Univariate analysis of the mesiodistal and buccolingual crown diameters of Cercocebus albigena, Cercopithecus aethiops and Cercopithecus ascanius revealed a complex pattern of contrasts depending upon which tooth dimension was compared. By contrast, multivariate analysis discriminated between the dentitions of Cercocebus albigena on the one hand and Cercopithecus aethiops and Cercopithecus ascanius on the other hand, but whether these differences reflected genetic or environmental factors requires further data.
Cholinergic innervation of vessels of the base of the brain
Authors: Borodulya A.V. , Pletchkova E.K.
Published: February 2009

Distribution and activity of acetylcholinesterase in the intramural nerve apparatus of vessels of the base of the brain have been studied with the histochemical method of Koelle-Gomori. On the whole, 268 arteries have been examined. The activity of the ferment is detected in the effector nerve fibers in the wall of all cerebral vessels constituting the system of the circle of Willis. The periarterial nerve apparatus of cerebral arteries of the anterior and posterior regions of the circle of Willis consists of two cholinergic plexuses – superficial and deep plexus forming a multilayered neural cover. The terminal parts of cholinergic nerve fibres at the border with the muscular coat show a granular structure. Moreover, nerve cells rich in active ferment are found in the cholinergic plexuses. Difference in the character of cholinergic innervation of vessels of the internal carotid and the vertebrobasilar region has been shown. The obtained data indicate that the vessels of the circle of Willis possess a reliable cholinergic system of nerve regulation which along with other systems, such as that of adrenergic nerve fibers, maintains the homeostasis of the cerebral blood flow.
Ultrastructure of articular cartilage of achondroplastic mice
Authors: Silberberg Ruth , Hasler Mary , Lesker Peggy
Published: February 2009

Articular chondrocytes of achondroplastic mice (cn/cn) resemble ultrastructurally those of their non-achondroplastic siblings (Cn/Cn or Cn/cn), except for premature deposition of glycogen and a tendency to undergo regression. The latter may be slight or extreme. The ultimate cause of the vulnerability of the chondrocytes and the cause of the heterogeneity of the reaction could not be determined with the method employed. Nevertheless, increased vulnerability accounts for cell death under conditions which are usually not injurious, and which may be either physiologic or altered by endogenous or exogenous factors.
Fine structure of precapillary arterioles of skeletal muscle in the rat
Authors: Stingl J.
Published: February 2009

The submicroscopic structure of the precapillary arterioles with a diameter of 25–6 µm was followed in m. spinotrapezius of the rat. The walls of the precapillary arterioles of the diameter of 25–20 µm consist of the endothelium, one layer of smooth muscle cells, 3–4 bundles of nerve fibres and a one-layer coat of fibrocytes. Arterioles of the diameter of 20–10 µm have an incomplete fibrocytar coat. Arterioles of the diameter of 10–6 µm also have an incomplete, disseminated muscular layer. The side-branching of true capillaries was not detected. Hence the described arteriolar portion cannot be considered as a metarteriole, but as a regulation device of a segmentary type, regulating the blood flow through the corresponding part of the capillary network as a whole.
Ultrastructural study on the meiotic prophase nucleus of rat oocytes
Authors: Vázquez-Nin Gerardo H. , Echeverría Olga M.
Published: February 2009

Rat oocytes in the meiotic prophase are studied by means of classical techniques of electron microscopy, preferential staining methods for DNA and RNA and specific enzymatic hydrolysis. The axial cores in leptotene and the lateral arms in the pachytene synaptonemal complex are composed by fibrils that keep a positive contrast after the application of the ethylenediaminetetraacetic acid staining method. They disappear with RNAse treatment, which reveals the presence of chromatin fibrils in the zone occupied by the cores. Preferential staining for DNA corroborates this evidence. Medial arm and lateral-medial fibrils are formed by ribonucleoproteic filaments that form bridges between pairing homologues in the zygotene. In the advanced pachytene stage, the RNA becomes scarce in these structures. No DNA can be detected either in the lateral-medial fibrils or in the medial arm. During diplotene the synaptonemal complex loses its individuality and the synaptic space becomes wider and irregular. At the same time, loss of chromatin and a large increase of RNA-containing particles occur. These processes lead to the typical interphasic arrangement of nuclear components seen in the dictyate stage.
Die Feinstruktur des Epithels des Ductus pancreaticus major des Schafes
Authors: Weyrauch K.D. , Schnorr B.
Published: February 2009

Light- and electron-microscopic and some histochemical investigations on the epithelium of the ductus pancreaticus major were carried out in sheep. At least six different cell types are recognizable: (1) nondifferentiated duct cells; (2) cells containing apical secretory granules; (3) goblet cells; the mucosubstances of type 2 and 3 are PAS- and Alcian-blue-positive, also reacting with methenamine silver; (4) ciliated cells, containing a single cilium with the microtubular pattern 9 + 2; (5) tuft cells with extremely long and wide microvilli and a pear-shaped cell body; (6) migrating cells, mainly lymphocytes and some assumed eosinophils, showing reaction to Mg++-activated ATPase.
Electromyographic study of the m. biceps brachii in movements at the glenohumeral joint
Authors: Furlani José
Published: February 2009

Our electromyographic studies on the participation of the m. biceps brachii in the movements of the glenohumeral joint, performed in 30 young adult male volunteers, permit the following conclusions: (1) In the movement of arm flexion, performed against resistance and with extended elbow, both the long and the short heads of the m. biceps brachii were active in all 30 volunteers examined. (2) The same movement of the arm, arm flexion with extended elbow, now without resistance, that is to say performed freely, showed both the long and short heads of the m. biceps brachii active in the majority of cases. (3) In the movements of arm extension, performed freely and against resistance, with extended elbow, and also in the movement of lateral arm rotation with flexed elbow, with and without resistance, the m. biceps brachii was absolutely inactive in all 30 volunteers examined. (4) In the movement of arm abduction, with extended elbow, the element of resistance to the performance showed itself to be important, since without it the m. biceps brachii was absolutely inactive; in the movement performed against resistance both heads of the muscle showed activity in 3 out of the 30 volunteers tested. (5) In the movements of arm abduction with and without resistance, with flexed elbow, the m. biceps brachii was active on occasion. (6) In the movements of arm adduction against resistance, with the elbow either flexed or extended, it was only the short head of the m. biceps brachii which was active, and this in half of the cases examined. (7) In the movements of medical rotation of the arm, with extended elbow, performed freely or against resistance, the long and the short heads of the m. biceps brachii each showed a different behaviour: the long head was always inactive, whereas the short one was seldom active.
Arteriovenous anastomoses in the skin of tropical cattle
Authors: Amakiri S.F.
Published: February 2009

As part of a general study of the vascular arrangement in the skin of cattle in tropical environments, the arteriovenous anastomoses (AVA) and other specialized vascular structures in the various skin sites of cattle were observed histologically. AVA were abundant in the skin from the scrotum, eye margin and the lower limb sites but were generally less numerous on the hairy body skin sites of cattle. Most of the AVA, especially those in the scrotal skin, were complex and tortuous S-shaped vessels, mainly located in the mid- and lower reticular layer and the mid- and lower papillary layer. The possible significance of their presence in various body sites, especially on the scrotal skin, is discussed.
The symphyseal cartilage and growth of the symphysis menti in the hamster
Authors: Trevisan Roberto A. , Scapino Robert P.
Published: February 2009

During growth of the mandible in the golden hamster a cartilage is formed at the symphysis menti. The way in which this cartilage contributes to growth and general mechanics of the symphysis is described.
Development of the Squamosomandibular articulation in the Mongolian gerbil (Meriones unguiculatus)
Authors: Gartner Leslie P. , Hiatt James L. , Provenza Vincent
Published: February 2009

The early development of the squamosomandibular articulation in the Mongolian gerbil was investigated from its inception through the 8th postnatal day. Pregnant gerbils were sacrified beginning on day 18 through day 23 of gestation by chloroform inhalation and the fetuses were extirpated and decapitated. Neonatal gerbils, 1–8 days of age, were also sacrificed. The severed heads were frozen in a cryostat and sectioned at 14 μm in frontal and transverse planes and stained in 1 % aqueous Safranin 0. The anlage of the mandibular joint along with membranous bony deposits lateral to Meckel’s cartilage in the vicinity of the presumptive body and ramus first appeared on the 18th gestational day. Condylar chondrogenesis occurred on the 20th prenatal day, and by day 22 of gestation chondrocytic hypertrophy was noted preparatory to osteogenesis. The presumptive articular disc was observed on the 21st gestational day while an upper and lower synovial cavity was discernible on the 22nd prenatal day. The squamosa and zygoma were first noted on the 20th postcoital day. There appeared to be a developmental lag from onset through completion of the gerbil squamosomandibular joint formation in comparison with that reported for the mouse and rat.
Lymph drainage of sinu-atrial node in man and dog
Authors: Eliška O. , Elišková M.
Published: February 2009

The lymphatic vessels of the sinu-atrial (SA) node were investigated after injection of Indian ink plus gelatine in 62 canine and 31 human hearts, the latter of subjects aged between 21 and 80. Lymph was found to be chiefly drained from the SA node of the dog by a vessel which collected lymph near the left margin of the SA node and ran between the superior vena cava and the right circumference of the aorta into the left cardiac lymph collector and through it into the left cardiac node. Approximately in two thirds of cases this main lymph drainage was supplemented by smaller lymphatic branches running into the right tracheo-bronchial nodes. In man, the main route of lymph drainage from the SA node is represented by one or two vessels which run to the right and upwards along the superior vena cava into the inferior tracheo-bronchial nodes (of the bifurcation), lying near the right bronchus. Little branches draining lymph into the cardiac collector are found rarely. It has become evident from histological sections that the lymphatic vessels run between the cells of the conduction system and the collagenous fibres of connective tissue and are not numerous.
A comparative numerical study of the trigeminal mesencephalic nucleus
Authors: Sivanandasingham P. , Warwick R.
Published: February 2009

A comparative statistical study of the trigeminal mesencephalic nucleus in 30 cats, 10 rats, 2 monkeys and 2 slow lorises has been presented. In contrast to previous results which show great discrepancies in neuronal counts in all species, and even in individuals of the same species, uniformity of estimates has been achieved by use of accurate counting methods, and clear definition of the parameters of this nucleus.
Fluorescence histochemical study of Auerbach’s plexus of the ileum of 6-hydroxydopamine-treated guinea pig
Authors: Qayyum M.A.
Published: February 2009

In the present investigation the action of 6-hydroxydopamine (6-OHDA) on Auerbach’s plexus of the ileum of the guinea pig has been studied with Falck and Hillarp’s histochemical technique. A single dose of 15–25 mg/kg of 6-OF£DA causes degeneration of some of the adrenergic nerve fibres after 6 h of treatment. 200–250 mg/kg of 6-OHDA is responsible for the total disappearance of nerve fibres in the ganglia and internodal strands within 24 h. 6 h after 100 mg/kg of 6-OHDA treatment, the intervaricose fibres have mostly disappeared and a few nerve fibres are swollen. The pre-terminal fibres are not much affected. After 24 and 48 h of 100 mg/kg treatment with 6-OHDA, most of the varicose and non-varicose fibres have diappeared and very few fibres are left, these having become intensely fluorescent and much swollen, probably due to the accumulation of storage granules transported to this site by axoplasmic flow. After 6–8 days of treatment with 6-OHDA, all the fluorescent fibres and cell bodies have disappeared.A few faintly fluorescent green and yellow cell bodies could also be observed; however, their chemical nature could not be determined.
An anomalous muscle (accessory subscapularis-teres-latissimus muscle) in the axilla penetrating the brachial plexus in man
Authors: Kameda Yoko
Published: February 2009

An anomalous muscle passing through the brachial plexus was found in 10 cases out of 380 sides of 190 human cadavers in the dissection course. The muscle was designated as ‘accessory subscapularis-teres-latissimus muscle’. This muscle arose near the lateral margin of the scapula, either from the surface of the subscapularis muscle or from the border of the quadrangular terminal tendon of the latissimus dorsi or from both of those sources when the muscle was divided into two heads. It ran obliquely upward to fuse with the insertion of the subscapularis. The largest anomaly was 2.5 cm in width and 7 cm in length. This muscle could be classified into three types on the basis of tis nerve supply and its relation to the brachial plexus. The type I muscle crossed over the axillary and lower subscapular nerves, behind the radial nerve and was innervated by the lower subscapular nerves. The type II muscle penetrated the brachial plexus separating the radial nerve into two roots: the upper from the posterior division of the upper trunk and the lower from the posterior divisions of the middle and lower trunks. The type II muscle was supplied by a branch of the radial nerve, which originated always at the same level as the origin of the thoracodorsal nerve. The type III muscle passed through the further more ventrocaudal level of the plexus: in one case it divided the radial nerve into an upper root from the posterior divisions of the upper and middle trunks and a lower root from the lower trunk, and, in another case, into an upper main root from all the three trunks and a lower slender root from the lower trunk. The type III muscle was supplied by branches from the radial and in addition from the thoracodorsal nerve in one case. In four out of ten cases, the subscapular or thoracodorsal artery also passed posterior to the anomalous muscle. A discussion was made on the nature of the anomalous muscle.
Die Synapsen an den Mitralzelldendriten im Bulbus olfactorius des wachsenden Kaninchens
Authors: Schwartze P. , Hoheisel G.
Published: February 2009

The postnatal development of synapses at the dendrites of rabbits mitral cells. Olfactory bulbs from 4 specimen of the 1st, 4th, 6th, 9th and 60th postnatal day were used. Relative mature unidirectional and reciprocal synapses are present at the mitral cell dendrites already at the first day. During postnatal development the amount of electron-dense postsynaptic material increase. The vesicles were always spheric; their number increase significantly with age only at granule cell side of the reciprocal synapses. Length and width of the synaptic cleft do not change with age.
Electron-Microscopic Identification of Amoeboid Microglia in the Spinal Cord of newborn rats
Authors: Ling E.A.
Published: February 2009

Electron-microscopic studies in the spinal cord of neonatal rats show, though rarely, the existence of amoeboid microglial cells. The cells are distributed singly and are found only in the spinal grey matter. They are characterized by having a round, prominent nucleus with peripheral chromatin clumps. The cytoplasm is endowed with a well-developed Golgi complex, and isolated profiles of rough endoplasmic reticulum. One striking feature of the cytoplasm is the presence of abundant lysosome-like granules. The cytoplasm, which is of moderate density, may be vacuolated. The surface of the cells often sends out pseudopodium-like processes. These, together with the presence of occasional phagosomes, indicate that the amoeboid cells are phagocytic. Thus, it is possible to generalize from the present and earlier findings that amoeboid microglial cells are normal cellular constituents in the maturing central nervous system and their temporary existence in the neonatal stage indicates the necessity of these cells for subsequent maturation of the nervous tissue.
Morphological, histochemical, autoradiographic and topographical evidences of the origin of the Langerhans’ cell from the melanocyte in the skin of the guinea pig
Authors: Shukla R.C. , Das M.
Published: February 2009

The microscopic anatomy of the nucleus, Golgi substance, mitochondria, etc. of type 1, 2, 3 and 4 albino melanocytes, type 0↕ and On albino intermediate cells of Billingham and Medawar and type I, II, III and IV albino Langerhans’ cells of the albino guinea pig, is presented in detail. The study has demonstrated that the albino melanocytes degenerate through sequential stages of intermediate cells of Billingham and Medawar, type I, II and III Langerhans’ cells to ultimately from type IV Langerhans’ cells. It has been shown that all the dendritic cells of the epidermis belonged to one class of cells. Autoradiographic techniques have shown that type 3 and type 4 melanocytes, respectively, bearing 6 and 5 round-tipped dendritic processes, divide by mitosis to form two daughter cells. One of these two daughter cells forms the intermediate cell of Billingham and Medawar. This cell, while transforming sequentially into type I, II, III and IV Langerhans’ cells, moves up through the Malpighian and granular layers of cells, to the stratum corneum. This type IV Langerhans’ cell is ultimately extruded out of the stratum corneum by exfoliation. The other daughter melanocyte remains at its place in the sub-basal zone to function as a mature melanocyte. The time for the passage of the daughter melanocyte to travel from the sub-basal zone to the stratum corneum layer was found to be 15 days.
Das Ependym der Seitenventrikel von Acanthodactylus pardalis (Reptilia, Lacertidae)
Authors: Hetzel Wolfdieter
Published: February 2009

Within the lateral ventricles of the brain of Acanthodactylus pardalis, different zones of ependymal cells are recognizable through their fluctuating changes from one into the other. The frontal pole of the hemisphere shows a rather homogeneous ependyma whose cells are laying together. Cell fibers are not visible. Farther caudally, the ventricular wall is subject to some alterations; there are more long-shaped cell nuclei. The ventricular sulci are areas of different ependymal structures. The sulcus terminalis represents a zone of dense-laying cells, whose nuclei possess in several regions more round or more elongated forms. An apical cytoplasmatic border and cilia are often clearly built out. The sulcus lateralis and the sulcus septo-archipallialis have a dense cell layer. The region below the medial cortex, near the sulcus septo-archipallialis, shows tanycytes with long basal fibers. The ependyma of the dorsal striatum shows dorsally as well as laterally, at the ventricle, areas with loosely arranged cells. The orientation of the cell nuclei to the ventricular surface is variable, especially at the ventricular wall of the septum and the opposite side of the striatum, where cell nuclei are to be found whose axis lays no more vertical but parallel to the ventricular surface.
Gross and microscopic anatomy of the biliary tract of the ferret
Authors: Poddar S.
Published: February 2009

The gross and microscopic anatomy of the biliary tract of the ferret was studied. The liver consisted of six separate lobes. The coronary ligament was not present. Histologically, it was very similar to that of man. The gall-bladder was present and was a pear-shaped sac. Its muscle coat was very thick and well developed. Hepatic ducts were multiple. Minor hepatic ducts formed three major ducts, the left, central and the right. A single common hepatic duct was not present. The cystic duct generally arose from the central duct. The bile duct was formed by the union of three major hepatic ducts. The pancreas consisted of two limbs, the left and the right. Each limb was drained by a duct which joined and formed a short main pancreatic duct. An accessory pancreatic duct extending from the duct of the left limb of the pancreas was usually present. The main pancreatic duct joined the bile duct nearly at right angles prior to the entry into the duodenum. Both ducts entered through the same osteum and coursed together. They ended in a common ampulla which opened into the major duodenal papilla situated at about 2.75 cm from the pylorus. The sphincter of Oddi was present and was very similar in disposition to that of man. The sphincter choledochus (of Boyden) was well developed. An accessory pancreatic duct was usually present. It opened into the duodenum at a minor papilla which was not prominent. The minor papilla was situated proximal and medial to the major papilla. Mast cells were not seen in the connective tissue sheaths of the liver, gall-bladder and pancreas.
Is the biomechanical principle of ‘antagonistic compensation’ valid also on the genetic level?
Authors: Riesenfeld Alphonse
Published: February 2009

According to ‘antagonistic compensation’, appendicular bones rendered hypofunctional by surgical means, become shorter and more robust. In normal Buffalo rats, appendicular bones are short and very robust and in Fisher rats they are long and gracile. Total body constitution is robust in Buffalo rats and gracile in Fisher rats. In GRL rats, appendicular bones are short but body constitution is gracile and the robusticity of the appendicular bones is intermediate between Fisher and Buffalo rats. Thus, total body constitution and relative length of the appendicular bones determine their robusticity, shorter bones being more robust than longer bones. In other words, the relationship between bone length and robusticity is the same in experimentally produced antagonistic compensation and genetically determined normal condition of rats.
Ultrastructure of the parathyroid glands in the chicks
Authors: Chan An Soo
Published: February 2009

The ultrastructure of the parathyroid glands in 4-week-old white leghorn chicks has been examined. The gland consists of chief cells arranged in diffuse cords or solid masses. The chief cells vary in electron density. The rough-surfaced endoplasmic reticulum is invariably moderately to well developed and consists of cisternae arranged in well-ordered patterns or distributed randomly. The Golgi complex consists of cisternae arranged in concentric layers, smooth-surfaced and coated vesicles. Cisternae of the Golgi complex arranged in circular and tortuous profiles are also observed. The chief cells contain occasional membrane-limited secretory granules 150–350 nm in diameter and with contents which vary in electron density. Secretory granules are distributed randomly in the cytoplasm and along with the plasma membrane. Images of fusion of coated vesicles with the plasma membrane are sometimes observed. The cytoplasm also contains round- to rod-shaped mitochondria, lysosome-like structures and occasional lipid bodies. Dark cells with electron-dense cytoplasm and containing organelles in close proximity are also observed. Morphological evidence of synthetic and secretory activities in the chief cells suggests active parathyroid function in the rapidly growing chicks.
Ultrastructural maturation of the neurohypophysis of the rat
Authors: Cannata Miguel Angel , Tramezzani Juan H.
Published: February 2009

The ultrastructure of the neural lobe of rats from birth up to the 340th day of life was studied. The distinguishing feature during the first week of post-natal life were axons consisting almost entirely of neurotubules, with only very few neurosecretory granules. Nerve endings contained scattered synaptic vesicles. Pituicytes had processes that were either thick or thin and long. The latter floated freely about an ample intercellular space. The intercellular space grew smaller during the following weeks. The neurosecretory granules increased in number, sometimes filling up the whole section of the axon. Dilated axons, from which the Herring bodies originate, began to appear, and the pituicytes also lost their thin processes. Between the 30th and 150th day of life, the neural lobe acquired the usual features of an adult gland. By the end of the first year, the connective tissue had developed greatly. The amount of axons containing lysosomes had increased. Furthermore, it can be said that the neurosecretory axon of the new-born rat is tubular and has no dilations. The neurosecretory granules are scarce. After the 21st day, the axonal dilations filled up with neurosecretory granules begin to grow, making the axon look like a string of beads.
The influence of the degree of maturation of donor tissue on the reconstruction of elastic cartilage by isolated chondrocytes
Authors: Moskalewski Stanislaw , Rybicka Elżbieta
Published: February 2009

Chondrocytes isolated from auricular cartilage of 1-, 14-, 28- and 56-day-old rabbits were injected intramuscularly as auto- or allogeneic transplants, and the development of the reconstructed cartilage was compared to that of intact tissue. Chondrocytes in cartilage of 1- and 14-day-old rabbits (younger group) were relatively uniform in size. During further development in situ (28 and 56 days) central cells increased considerably and many of them became binucleat-ed. Cartilage reconstructed by chondrocytes from the younger group of animals displayed regular arrangement of cells, i.e. smaller cells at the periphery and larger in the centre. Transplantation of chondrocytes from 28 or 56-day-old rabbits (older group) led to the reconstruction of cartilage with irregular distribution of cells, i.e. some large cells were located at its periphery, while in the centre smaller and larger cells were intermingled in a haphazard manner. Elastic fibres were scanty and thin in cartilage of 1-day-old animals, but their number and size increased with time and they displayed a characteristic pattern. Formation and maturation of these fibres proceeded in cartilage reconstructed by chondrocytes from the younger group of animals similarly as in the intact tissue. Chondrocytes from the older group of rabbits reconstruct -ed cartilage in which the number of elastic fibres was reduced and their arrangement appeared irregular.
The role of bone remodelling in the healing of extraction socket in rats
Authors: Sela S. , Jaffe A.
Published: February 2009

Bone remodelling of post-extraction socket was studied in the past by various methods. In the present work, the process was studied with the scanning electron microscope (SEM). The SEM is essential for a three-dimensional description, particularly when hard tissues are involved. Initiation of healing on the first week was characterized by formation of delicate spongy bone. The trabeculae were distributed in a centrifugal pattern around the interradicular bone. Socket healing on the second week consisted of thickened, regularly distributed trabeculae. This was accompanied by resorption and flattening of the peri-socket sharp ridges. The third and fourth weeks were characterized by small bone marrow spaces and a gradual transformation of the trabecular bone to one of cortical-compact nature. The typical characteristics of resorbing, resting and forming surfaces were detected in all phases of socket healing. Two major patterns of ossification could be shown: Firstly, calcification of collagen bundles in osteoblastic lacunae. Concentrations of such lacunae were related to periosteal activity and were also found in areas most probably occupied previously by blood vessels. Another pattern of mineralization was in the form of globular calcospherites and is reminiscent of calcification of ground substance.
Histological observations on the ependyma of the ventriculus mesencephali in the guinea pig
Authors: Mitro A. , Kiss A.
Published: February 2009

The ventriculus mesencephali is localized in front of the cerebellum and forms a recessus of the dorsal wall of the aquaeductus mesencephali. The ependyma was found one-layered; in some places clusters of cubic or cylindrical ependymal cells occur. Some cells show basal processes. Supra-ependymally there are homogeneous globules and intraventricular nerve fibres. The occurrence of different types of ependymal cells indicates a morphological variability of ependyma even within this small part of the ventricle system of the brain.
Fine structure of the retinal epithelium of the spectacled caiman (Caiman sclerops)
Authors: Braekevelt C.R.
Published: February 2009

The fine structure of the retinal epithelium, Bruch’s membrane and choriocapillaries has been studied by electron microscopy in the spectacled caiman (Caiman sclerops). The retinal epithelium throughout most of the retina is morphologically very typical of that described for other vertebrates. This typical appearance involves a single layer of pigmented cuboidal cells with extensive basal (scleral) infoldings and numerous apical (vitreal) processes enclosing photoreceptor outer segments. A semicircular area of the retinal epithelium in the superior fundus is, however, further specialized as a tapetum lucidum. The reflecting material consists of a large array of guanine, diffusely scattered within the epithelial cells. Centrally in the tapetal area, no melanosomes are found, indicating a non-occlusible tapetum. At the edge of the tapetum, however, both guanine crystals and melanosomes are found within the epithelial cells. In most other respects, the morphology of the epithelial layer in the tapetal region is not strikingly different from that in the non-tapetal area. Bruch’s membrane everywhere displays the typical pentalaminate structure described for most vertebrates. The choriocapillaris is also typical in that numerous fenestrations are present in the endothelium bordering Bruch’s membrane.
Intra-acinar nerve terminals in four rodent parotid glands
Authors: Bloom Gunnar D. , Carlsöö Bengt , Gustafsson Hans
Published: February 2009

The distribution of autonomic nerves was studied at the ultrastructural level in guinea pig, hamster, mouse and rat parotid glands employing the potassium permanganate fixation/staining technique. In the periacinar connective tissue numerous unmyelinated nerves were observed in all the glands examined. Two types of axonal enlargements were encountered, one contained small, dense-cored vesicles (500–600 Å in diameter) as well as a few large (∼ 1,000 Å in diameter), the other exhibited numerous agranular vesicles (500–600 Å in diameter). In all glands, axons devoid of Schwann cell investment were visualized at the base of the acinar cells, inside the basement membrane and in intimate contact with gland cells. In addition, axonal enlargements of both types were encountered in the intervening space between neighbouring acinar cells. Whereas nerve terminals within the gland epithelium were extremely common in the rat, mouse and hamster, their frequency was much lower in the guinea pig. In addition, only parenchymal varicosities of the adrenergic (dense-cored vesicles) type were encountered in the latter species. No intraepithelial nerves were observed in the striated ducts. However, axonal enlargements were present in the subepithelial connective tissue and were most numerous in the hamster parotid gland. The above findings confirm the dual innervation of the serous acinar cells of the guinea pig, hamster, mouse and rat parotid glands by both parasympathetic and sympathetic nerves. Furthermore, there exists a close membrane-to-membrane contact between autonomic nerves and salivary gland cells.
The effect of methylazoxymethanol on growth of the spheno-occipital synchondrosis in rats
Authors: Melsen B. , Moss M.L.
Published: February 2009

Methylazoxymethanol (MAM) causes a reduced development of cerebellum and medulla oblongata in rats. To study the effect of external factors on growth of the spheno-occipital synchondrosis, four litters of rats each of five animals were treated with MAM within 12 h after birth and sacrificed after 30 days. A similar number od control rats were sacrificed at the time when their skull length was equal to that of the experimental rats. Microradiographical and histological investigations showed that the cranial base lordosis was more pronounced in the MAM rats than in the controls, and that the width of the spheno-occipital synchondrosis was reduced mainly due to reduction in the central zone.
Early development of human lung
Authors: Yokoh Y.
Published: February 2009

Two old conceptions on the development of the human lung, one of ‘stem and branch’, and the other of ‘eparterial’, do not seem to be reasonable to the present author. The lingual segment of the upper lobe of the left lung must be a portion corresponding to the middle lobe of the right lung.
Scanning electron microscopy of ejaculated baboon (Papio anubis) spermatozoon
Authors: Chrétien F.C. , Dubouch P. , François N.
Published: February 2009

Scanning electron microscopy has been used in order to provide the morphological study including comparative measurements of the main parts of the Baboon spermatozoon. If the dimensions of the head and the mid-piece are fairly close to the human spermatozoon, the Baboon spermatozoon is practically twice as long as the human one. In the Baboon spermatozoon, the head appears smooth with only a light transversal furrow at the level of its posterior third, which probably marks the limit of the posterior border of the equatorial segment. The mid-piece, a conical trunk, is larger in its anterior part than at the level of its posterior extremity. The end-piece appears very short as compared with the total length of the sperm cell. The technical modalities of the preparation and the possibility of artifacts are briefly discussed.
Effects on hamster vaginal development of a single dose of testosterone or estradiol given neonatally
Authors: Hisano N.
Published: February 2009

Postnatal injections of a single dose of testosterone propionate or estradiol benzoate to newborn female hamsters produce a precocious vaginal opening at 5 days of age. Vaginal postnatal development, histologically, has shown that in testosterone-propionate-injected animals sinusal vagina is absent. The Müllerian vagina presented a stimulated epithelium at early ages. After 40 days, the Müllerian epithelium was stratified keratinized, with zones of stratified cuboidal epithelium. In estradiol-benzoate-treated animals, the Müllerian epithelium rapidly changes to stratified keratinized epithelium (10 days), with zones of stratified cuboidal after 20 days of life. The sinusal epithelium was stratified squamous at 10 days, and after 40 days changes to stratified keratinized epithelium were seen. Probably, early changes are due to a direct effect of steroid action. Later effects are due to ovarian secretion. Histologically, no significant changes were observed in the preputial and urethral glands. The clitoris showed malformations.
Lichtmikroskopische und elektronenoptische Untersuchungen morphologischer Veränderungen von Muskelfasern bei freier autologer Muskeltransplantation
Authors: Lischka A. , Holle J. , Freilinger G.
Published: February 2009

The extensor digitorum longus muscle of the rat was denervated and transplanted onto the vastus lateralis muscle of the same limb 1 or 2 weeks after denervation. The morphological changes appearing after transplantation were examined by light and electron microscopy. Only three to four superficial layers of muscle fibres remained unchanged after transplantation. The other parts of the transplanted muscle degenerated nearly entirely during the first 10 days. The myofibrils were removed by macrophages, thus within the tubes of basal lamina no contractile material could be observed. In a second period, regeneration of myofilaments took place. 6 weeks after transplantation, newly formed muscle could be observed, capable of normal function. The diameter of the fibres, however, was smaller and the connective tissue between the fibres markedly increased as compared to the normal muscle of the other side. The importance of the findings for muscle transplantation, especially the relationship between satellite cells and myoblasts, is discussed.
Collagen fiber orientations in human secondary osteons
Authors: Frasca Peter , Harper Richard A. , Katz Lawrence
Published: February 2009

Scanning electron microscopy studies of decalcified human secondary osteons were conducted to determine correlations in fiber orientations in these osteons with their appearance under crossed polaroids. Using a new sample preparation technique, osteons were prepared to expose many of their lamellar interfaces. By studying many such samples, it was concluded that osteons which appear ‘dark’ under crossed polaroids contain fibers with orientations having little or no transverse component, whereas ‘bright’ osteons possess fiber orientations with transverse and longitudinal components. ‘Intermediate’ osteons have been found to contain fiber orientations richer in longitudinal component than in transverse.
A modified grid apparatus for stereological analysis of light and electron micrographs
Authors: Moore R.N. , Penney D.P. , Averill K. , Kurtz D.
Published: February 2009

A simplified and inexpensive grid apparatus for use with the differential point counting technique of stereological analysis of cellular and organellar volumes is described.
Changes in the dentition of the guinea pig following total section of the inferior alveolar nerve and vessels
Authors: Isotupa K. , Rönning O.
Published: February 2009

The inferior alveolar nerve was cut or the vessels entering the mandibular canal were damaged in 39 guinea pigs at 10 days of age. Possible changes in the incisors were recorded during a 100-day observation period whereafter the animals were killed and the skulls freed of soft tissues; at this time, 35 skulls were found suitable for further examination. The changes in the mandibular incisors on the operated side became observable 30–40 days post-operatively as discolourization, a ‘trauma line’ around the tooth, narrowing of the tooth or total loss of it’s visible part. In the guinea pigs with the nerve cut (group A), such signs of maldevelopment were seen in 5 out of 19 animals, whereas the corresponding figure for the animals with the damaged vessels (group B) was 14/16. All incisors in group A and 13 out of 14 in group B recovered from the state of maldevelopment; one animal in group B showed complete loss of the incisor. The molar region was examined only from the cleaned skulls. In group A, the first molar was deformed in two animals; in group B, seven animals displayed either maldevelopment of the first molar or the first and second molar or complete loss of the first molar. No malformation of the third molar was observed. With two exceptions, the deformation or loss of molars occurred in combination with incisor maldevelopment. The malformations were considered to result from a disturbed blood supply. In group A, the dental changes may perhaps be ascribed to a short-term interference with the blood supply during the operation. The variable results in group B seem to imply that the mandibular teeth receive at least part of their blood supply from vessels besides those entering the mandibular canal. The innervation appears to have a subordinate role in the restoring of the morphology of continuously erupting teeth.
Mucopolysaccharides in the dog spinal cord and dorsal root ganglia
Authors: Garcia-Segura L.M. , Martinez-Rodriguez R. , Toledano A.
Published: February 2009

A histochemical study of mucopolysaccharides in the dog spinal cord and dorsal root ganglia is reported in this paper. The histochemical techniques used were the following: PAS, colloidal iron, toluidine blue (pH 5.4 and 3.5), thionine (pH 5.4 and 3.5) and alcian blue 8GX (pH 1 and 2.5). Some histological stains were used also. Two types of neurons could be observed in spinal cord sections stained with colloidal iron techniques. In some neuron a border line of mucosubstances could be seen. In the dorsal root ganglia, different patterns of Nissl bodies distribution in neurons were described. This different distribution of Nissl bodies is associated with different metachromatic colorations of neurons. By using the colloidal iron method, two types of neurons were also revealed in the dorsal root ganglia: some neurons are of a yellow, small-sized and star-shaped type and others are of a light green, larger and round-shaped type. Mucosubstances in the endoneurium and perineurium of nerve fibers, in the Ranvier nodules and in the Schmidt-Lantermann incisures were observed. The possibility that the functional rhythm in some cases might be responsible for the difference in coloration between the dorsal root ganglia neurons is suggested.