bluuebunny/crossref_metadata_2025_split huggingface dataset:
Studies on the nerve endings in the visceral pleura
Authors: Dwinnell Frank L. 
Published: February 2005

AbstractThe visceral pleura of 12 dogs, eight lambs, nine monkeys and four rabbits was studied by methylene blue immersion. Nerve terminations were found in the pleura of all specimens. The following types of nerve endings and patterns of innervation were observed. (1) Free fiber endings arose from small myelinated fibers and terminated in the caudo‐ventral lips of the lobes. The parent fibers of these and all other endings arose, in the lamb, rabbit and dog, from nerve bundles radiating from the hilus onto the inter‐lobar and diaphragmatic pleural surfaces. In the monkey, parent fibers arose from a complex hilar plexus of nerve bundles before spreading out within the pleural surfaces. (2) Complex unencapsulated endings were seen in all specimens distributed evenly over the inter‐lobar and diaphragmatic pleural surfaces. These arose from myelinated fibers which terminated in two or more complex endings. In the monkey, parent fibers may form an anastomotic network before terminating. (3) In the dog, an “end‐net” formation was found which appears to be a type of complex unencapsulated ending. This “end‐net” is formed by the anastomosis of the terminal branches of several small myelinated fibers.
Fine structure of the surface of mouse hepatic cells
Authors: Heath Trevor , Wissig Steven L. 
Published: February 2005

AbstractMouse hepatic cells appear in thin sections as polygons with six or more sides. The plasma membrane covering these sides may contact either bile canaliculi, the narrow intercellular space, the space of Disse or extensions of the space of Disse between adjacent cells. The plasma membrane covering microvilli in bile canaliculi and the space of Disse is thicker than that in contact with the narrow intercellular space. Bile canaliculi, which contact about 6% of the perimeter of each cell, are each separated by tight junctions from the narrow intercellular space. This space contacts more than one‐half the perimeter of each cell and is about 220 Å in width. It is continuous around the occasional studlike junctions which occur, but is interrupted at frequent intervals by circumscribed tight junctions, and occasionally by desmosomes. The narrow intercellular space is in free communication through the space of Disse with the plasma space. An interstitial fluid space, separate from the plasma space, does not occur in the liver lobule. Protein molecules from plasma enter hepatic cells in both coated and pinocytotic vesicles. These vesicles are derived from invaginations of the plasma membrane that borders the narrow intercellular space and the spaces between microvilli in the space of Disse. Pinocytotic vesicles may also incorporate fat droplets into hepatic cells.
Effects of triton WR‐1339 on the rat yolk sac placenta
Authors: Schultz Phyllis W. , Reger James F. , Schultz Richard L. 
Published: February 2005

AbstractThe cytochemistry and ultrastructure of the lysosomal area of the rat's yolk sac placenta was studied at various stages of development. The lysosomal area, located at the apical end of the yolk sac epithelial cell between the microvillous border and the nucleus, consisted of dense bodies that persisted from day 10 of pregnancy through gestation and multivesicular bodies that are present only through day 12. Acid phosphatase activity was restricted to the dense material and to the membranes of this area. Two types of pinocytotic vesicles were present in all stages of development. One was a tubular structure containing dense material and the other, a saccular, clear structure containing a “fuzz‐lining” and membrane remnants. Possible relationships between the pinocytotic vesicles and the dense and multi‐vesicular bodies were considered.The injection of Triton WR‐1339 on day 11 of pregnancy resulted in a vacuolation of the dense and multivesicular bodies. This vacuolation began 15 minutes after injection and maximum effect was reached within 12‐‐24 hours. A reorganization of the lysosome area occurred on days 15‐‐16 in those animals in which pregnancy continued to term. This reorganization consisted of an increase in the dense material within the vacuoles and a reduction in vacuole size. The vacuoles remained distended in those animals in which death and resorption of the fetus occurred. The first cellular changes associated with death occurred between 48‐‐60 hours post‐injection. The microvilli became shorter, thicker and reduced in number; the pinocytotic vesicles disappeared from the cell surface; the endoplasmic reticulum became dilated and vesiculated; and vesicles were formed from the cristae of the mitochondria.With the injection regimen used in this study, 25% of the litters were resorbed while the remainder of the pregnant rats delivered viable fetuses at term.
Studies on guinea pig oocytes. II. Histochemical observations on some phosphatases and lipid in developing and in atretic oocytes and follicles
Authors: Adams Eleanor C. , Hertig Arthur T. , Foster Susanne 
Published: February 2005

AbstractNormal guinea pig oocytes develop in an environment of AMPase within the granulosa cells of the wall, the cumulus and the latter's projections that traverse the zona pellucida to terminate at the surface of the oocyte. Oocytes in developing non‐vesicular and small vesicular follicles have an ATPase activity at their surface, which appears to indicate specialized absorptive mechanisms confined to these early stages of development. Acid phosphatase, present in granules scattered throughout the cytoplasm of all developing oocytes, may be evidence of a mechanism in this species, whereby the oocyte hydrolyzes unidentified nutritional reserves.Histologically normal appearing oocytes in atretic vesicular follicles may show deviations from the normal histochemical pattern, i.e., clumping and subsequent loss of acid phosphatase activity or a band of AMPase activity at the periphery of the oocyte representing apparent enlargement of the terminals of projections of the cumulus. These deviations may reflect disturbances of granulosa cell‐oocyte transfer as a consequence of beginning atetric processes in the follicle wall. By the eighth day of the estrous cycle the granulosa layer of many medium sized follicles has been invaded by a few long strands of nucleoside polyphosphatase positive thecal connective tissue often carrying a small blood vessel. This early stage of atresia is apparently followed by shedding of the granulosa layer and hypertrophy of the thecal layer which begins the transformation of atretic follicles into interstitial masses.
The interrelation of the digestive and skeletal systems as determinants of tooth position
Authors: Brodie Allan G. 
Published: February 2005

AbstractIn spite of the many differences between teeth and bone in their phylogenetic and embryologic origins, modes of growth, disease and repair processes, the two continue to be equated together in most matters relating to their functioning positions.On the basis of a variety of studies by others and recent quantitative longitudinal investigations by himself the author seeks to demonstrate that the positions of the teeth are under the control of different body systems, viz., the skeletal and the digestive. The first controls the root apices, the second the crowns.
Microradiographic visualization of structure in bones of the masked shrew, Sorex cinereus
Authors: Felts William J. L. , Spurrell Francis A. 
Published: February 2005

AbstractSorex cinereus, the masked shrew, is nearly the smallest of mammals. The femur, metatarsal, phalanges and mandible of wild‐trapped animals were examined by a variation in the technique of contact microradiography. Purpose of the investigation is the exploration of some aspects of the question of size as a factor in structural complexity in bone, as well as the possibilities of the shrew in studies of skeletal aging. Comparison is made with bones of the laboratory mouse and rat.Limb bones of the masked shrew are avascular. Vascularity of the mandible appears related primarily to maintenance of dental tissues. The femur is comparatively simple, its sparce spongiosa consisting of relatively large trabeculae. Diaphyseal compacta appears to be of maximum thickness for the avascular state. Tubular foot bones are without spongiosa and bone on their articular surfaces is nearly as thick as that in the diaphysis. Metatarsals and phalanges of mice have the same gross structure but are vascular. These bones in the rat have trabeculae in functional patterns.The simplicity of structure of these minute bones, and the drastic structural modification of bones of apparently starved or stressed animals, indicates potential utility of the shrew in experimental investigations.
Continuous attachment of the periodontal membrane
Authors: Kraw Allan G. , Enlow Donald H. 
Published: February 2005

AbstractA polychrome stain for differentiating precollagenous and collagenous fibers, and tetracycline for labeling bone changes were used in young rats to trace adjustments involved in movements of teeth within bone. Distinct differences were seen in fibrous attachments on depository and resorptive bone surfaces. These are associated with shifts of the periodontal membrane as the root and surrounding bone undergo drift. Some resorptive areas receive total destruction of fibrous attachment. Other areas involve a process of fibrous conversion as ordinary fibers of the bone matrix become uncovered during bone removal and function as periodontal fibers anchored into the receding bone surface. An intermediate zone of the periodontal membrane functions to progressively shorten distal ends of these same fibers and to relink them with newly formed precollagenous fibrils. These become continuous with mature fibers attached to the cementum. On depository surfaces, outer fibers of the membrane become embedded into new alveolar bone, and former precollagenous fibrils of the inward‐shifting intermediate zone translocate to become the new outer zone. Continuous relinkage is simultaneously maintained between the inner and outer zones. Haversian remodeling occurs beneath resorptive surfaces and re‐anchorage is thereby established in specific areas where total destruction of fibrous connection had previously occurred.
An electron microscopic and radioautographic study of the rat parotid gland after actinomycin D administration
Authors: Han Seong S. 
Published: February 2005

AbstractRat parotid glands have been examined by electron microscopy and radioautography (H3‐leucine incorporation) at various intervals following an injection of actinomycin D in the amount of 0.125 μg per gram of body weight. Light microscopic observations confirmed results from previous experiments similar to this. Radioautographs showed a definite drop in number of silver grains in acinar cells of the parotid from experimental animals. This was most pronounced in 7‐day rats which received H3‐leucine four hours prior to sacrifice. Electron microscopic observations revealed a generalized reduction in number and degree of the organization of organelles concerned with protein synthesis. Furthermore, frequent appearances of lipid droplets, cytolysomes and crystalloid structures were noted. Changes of the nucleolus included the reduction of its size and the formation of spherical encapsulated bodies. A brief discussion is made of these results in relation to the biochemical nature of actinomycin effects on protein producing cells.
Central projections of portions of the vestibular ganglia innervating specific parts of the labyrinth in the rhesus monkey
Authors: Stein Bennett M. , Carpenter Malcolm B. 
Published: February 2005

AbstractIn 40 monkeys attempts were made to determine the central projections of cell groups in the superior and inferior vestibular ganglia (SVG, IVG) which innervate distinctive parts of the labyrinth, by: (1) severing peripheral branches of the ganglia, (2) resecting portions of the ganglia, and (3) producing discrete partial lesions in the ganglia. Serial sections of the temporal bones were stained with Sudan black B, and Nauta‐stained sections of the brain stem were cut transversely and horizontally.Section of peripheral branches of the vestibular ganglia produced no central degeneration and unreliable cell changes in the ganglia. Partial lesions of the SVG, innervating the cristae of the anterior and lateral canals, produced maximal degeneration in the superior and medial (rostral part) vestibular nuclei. Partial lesions of the SVG, innervating the macula of the utricle, produced maximal degeneration in the medial (caudal part) and inferior (mediodorsal part) vestibular nuclei. Some descending fibers related to the utricle entered the accessory cuneate nucleus.Discrete lesions in portions of the IVG indicate relationships between: (1) the crista of the posterior canal and the superior vestibular nucleus (caudomedial part), and (2) the saccule and dorsolateral parts of the inferior vestibular nucleus. Cells of the vestibular ganglia innervating distinctive parts of the labyrinth have unique, as well as common, central projections within the vestibular nuclear complex.
An electron microscopic study of the modification by monosodium glutamate of the retinas of normal and “rodless” mice
Authors: Cohen Adolph I. 
Published: February 2005

AbstractSodium‐L‐glutamate was administered to post‐natal Swiss albino and agouti C3H/HeJ “rodless” mice. In both cases there was at two months a marked reduction in myelinated axons of the optic nerve from about 25,000 to less than 225 axons but Swiss mice had more ganglion cell somas than axons. Glutamate‐treated eyes seemed smaller and the lenses were 65% of the weight of control lenses. The inner nuclear layer of Swiss‐glutamate retinas was reduced from 5–7 nuclei deep to 1–2. In treated Swiss mice the receptor concentration appears unchanged and electron microscopy revealed that both spheroidal and pedicular receptor terminals were contacted by presumed neurites of second order neurons. There was a small, relative increase in terminals of bipolar neurons in the markedly reduced inner plexiform layer. Relative to these findings a description is given of normal synaptic arrangements. In glutamate‐treated “rodless” mice at two months the retina contained two rows of nuclei. Imbricated processes of glial cells of Müller faced the pigment epithelium and the retina contained scattered ganglion cells, bipolar cells, and other neurons less readily characterized. At two months most glutamate‐treated mice, rod containing or “rodless,” had a direct pupillary response and a detectable but obviously weaker consensual response. Preliminary examinations of animals one year after glutamate treatment showed receptor deterioration in albino animals and further retinal deterioration in both groups. The two surviving C3H‐glutamate animals possessed milky cataractous lenses, however full but sluggish direct iris constrictions could be elicited.
Physical, histological and roentgenographic characteristics of the grey lethal mouse
Authors: Doykos John D. , Cohen M. Michael , Shklar Gerald 
Published: February 2005

AbstractA project was undertaken to investigate the development of dental and osseous abnormalities in the grey lethal mouse. In this study particular attention was focused on the nature of these anomalies and the exact time of onset.Twenty‐five grey lethal mice, with siblings serving as controls, were sacrificed at two day intervals from the eighth to the twentieth day. Color photographs and lateral full body radiographs were taken at each developmental stage studied. Microscopic sections of the jaws and femurs of each animal were prepared and stained with hema‐toxylin and eosin.Abnormalities in the incisor region of the grey lethal mouse were demonstrated radiographically at the eighth day. Interference with Hertwig's sheath of the developing first molar tooth was observed histologically at the eighth day. Establishment of molar root bifurcation was not observed in the grey lethal mice. Bone resorption was retarded in both jaws and femurs. Differences between experimental and control animals became more apparent with increasing age.It was thought that apical root development and osseous apposition in the area of bifurcation of developing molars, as well as resorption of bone occlusal to the crowns of the teeth are constituents in axial movement of developing teeth. Evidence tending to support this concept is presented, since all three functions were shown to be altered in the noneruption dentition of the grey lethal mouse.
Efferent fibers of the subthalamic nucleus in the monkey. A comparison of the efferent projections of the subthalamic nucleus, substantia nigra and globus pallidus
Authors: Carpenter Malcolm B. , Strominger Norman L. 
Published: February 2005

AbstractA study was made to determine the efferent projections of the subthalamic nucleus in the monkey. Because of the impossibility of producing lesions in this nucleus, not involving adjacent structures, lesions were produced by different stereotaxic approaches. Comparisons were made with degeneration resulting from localized lesions in substantia nigra and globus pallidus. Degeneration resulting from these lesions was studied in transverse and sagittal sections stained by the Nauta‐Gygax method.Efferent fibers from the subthalamic nucleus pass through the internal capsule into the medial pallidal segment; a few fibers are distributed to the lateral pallidum. Some subthalamic efferent fibers pass to the contralateral globus pallidus via the dorsal supraoptic decussation, but none projection to the thalamus.Nigral efferent fibers project to parts of the ventral anterior (VAmc) and ventral lateral (VLm) thalamic nuclei. The medial pallidal segment gives fibers to: (1) ventral anterior (VA), ventral lateral (VLo) and centromedian (CM) thalamic nuclei, and (2) the pedunculopontine nucleus. The lateral pallidal segment projects exclusively to the subthalamic nucleus. Thalamic projections of the substania nigra and globus pallidus are distinctive. Subthalamic projections to the globus pallidus are more profuse than those of the substantia nigra.The following hypothesis is presented: Subthalamic dyskinesia, due to lesions in the subthalamic nucleus, is a consequence of removal of inhibitory influences acting upon the medial segment of the globus pallidus.
The adrenergic nerve supply to the female reproductive tract of the cat
Authors: Rosengren E. , Sjöuberg N.‐O. 
Published: February 2005

AbstractPilot studies on the fluorescence histochemistry of the adrenergic innervation to the female reproductive tract in different mammals revealed a conspicuously well developed innervation in the cat. Moreover, the female genital tract of the cat is studied extensively with regard to the pharmacology of adrenergic mechanisms. An exact knowledge of the adrenergic innervation apparently would make the cat a particularly suitable model for functional studies on the involvement of neuronal adrenergic mechanisms in the reproductive tract.Fluorimetrically, noradrenaline was the only catecholamine occurring in measurable amounts in nonpregnant cats. The amine seemed to have an exclusively neuronal distribution, although a comparatively small fraction may be also located in “chromaffin” cells present in relation to ganglion formations.A considerable number of adrenergic nerve terminals were found in all organs of the reproductive tract. Consistent numbers of these terminals were directed to various structures forming the ovarian parenchyma and to the smooth muscle coats of the oviduct, uterus, and vagina. The rest of the innervation seemed to be of vasomotor nature. The histochemical results agree well with the high level of noradrenalin, 1.22–4.93 μg/gm, found in the different organs.Denervation experiments revealed that the postganglionic sympathetic innervation reaches the oviduct, uterus, and vagina partly by way of the hypogastric nerves, and partly by way of short adrenergic neurons originating from adrenergic ganglia that could be directly visualized in the region of the uterovaginal junction. The ovarian adrenergic innervation seemed to arise more proximally, probably directly from the sympathetic chain.
The fine structure of neurons and satellite cells in the trigeminal ganglion of cat and monkey
Authors: Pineda Anselmo , Maxwell David S. , Kruger Lawrence 
Published: February 2005

AbstractNeurons and satellite cells in the trigeminal ganglion of cats and monkeys fixed by aldehyde perfusion were examined in the electron microscope. The fixative employed and its tonicity appear to be critical factors in accounting for some of the differences noted in earlier descriptions. With satisfactory preservation, only one variety of neuron is seen on the basis of cytoplasmic and nuclear features, although there is a substantial size range. Interdigitating processes of neurons into the satellite cell capsule probably accounts for the axon terminals and intracapsular nerve nets reported in early metallic impregnation studies. Axonal glomeruli are encased in satellite cells and become myelinated by Schwann cells as the axon leaves the region of the neuron soma.Satellite cells reveal layers of attenuated processes forming unusual membrane complexes around the axons. The external surfaces of the satellite cells are completely invested with a prominent basal lamina, which is continuous with that surrounding the Schwann cell at the first “internode.”
Catagen in the hairless house mouse
Authors: Orwin D. F. G. , Chase H. B. , Silver A. F. 
Published: February 2005

AbstractA morphological and histochemical study was made of some aspects of the catagen phase of the first hair cycle in hairless (hr) mice.The histochemical tests used included those for sulphydryl and disulfide groups, collagen, and periodic acid‐Schiff‐reactive materials. Measurements were made of skin thickness, follicle length and for follicles in catagen VI and VII, epithelial column length, length of hair shaft in the skin, the width of glassy membrane and connective tissue sheath, and the width of collagen in the glassy membrane. The results showed that:

The mutant epithelial column shortens at a slower than normal rate so that at catagen VII, the total follicle length is greater than normal. The position of the mutant hair shaft in the skin is normal at this stage.
The keratinization sequence of the mutant club appears normal. The failure to form an anchoring brush is associated with a morphological variation in the cell shapes and fibrils of the club.
The inner root sheath of the mutant follicle, although apparently keratinizing in the normal sequence, extends further up the follicle than normal and also further down, enclosing the club.
The glassy membrane and connective tissue sheath of the mutant are abnormally narrow due mainly to a marked reduction in collagen, and to a narrower band of PAS‐positive material.