bluuebunny/crossref_metadata_2025_split huggingface dataset:
Retrograde cell degeneration in adult cat after hemidecortication
Authors: Peacock John H. , Combs C. Murphy 
Published: January 2005

AbstractEighteen adult cats were hemidecorticated by surgical aspiration and allowed to survive 14 to 54 days. Severe cell loss occurred in the following thalamic nuclei: anterior ventralis; anterior medialis, except for cell retention in the dorsomedial third; ventralis anterior; ventralis lateralis; ventralis posterolateralis; ventralis posteromedialis; lateralis dorsalis; lateralis posterior; posterior; pulvinar; geniculatum laterale, pars dorsalis; and geniculatum mediale, pars principalis. Partial cell loss was found in the anterior dorsalis, ventralis medialis, submedius, reuniens, and geniculatum mediale, pars magnocellularis. Paracentralis retained a lower than normal number of Neurons in its medial half, with scattered cells appearing throughout its lateral half and in the adjacent centralis lateralis. The pale‐staining reticular nucleus had nearly a normal complement of cells in its ventral half, whereas the dorsal half retained only scattered cells. No consistent pattern of degeneration was found in medialis dorsalis. The following structures were normal: paratenialis, interanteromedialis, rhomboidens, centralis medialis, parafascicularis, centrum medianum, and geniculatum laterale, pars ventralis. Likewise, no degeneration was displayed by subthalamic and midbrain nuclei. Throughout this study, no differences were discernible which could be ascribed to the variation in postoperative survival times.
Initial collaterals of motor axons within the spinal cord of the cat
Authors: Prestige M. C. 
Published: January 2005

AbstractThe histological evidence for the existence of motor initial collaterals is contradictory and insufficient. The literature is reviewed. Axons of 27 motoneurons of near term cat fetuses have been impregnated by the Golgi rapid method, and the stained structures described. A wide variety of collaterals occur randomly, mean 0.72 ± 0.12 collaterals per 100 μ. The evidence that impulses in initial collaterals of motor axons cause recurrent inhibition is discussed.
The structure of the central nervous system of the slug Arion ater L., with notes on the cytoplasmic inclusions of the neurons
Authors: Smith B. J. 
Published: January 2005

AbstractThe nervous system of Arion ater consists of a complex central circumesophageal nerve ring, the two buccal ganglia, the digitated ganglia in the optic tentacles ganglion masses. The supra‐esophageal ganglion mass is made up of the two cerebral ganglia, each divisible into pro‐, meso‐ and meta‐cerebrum, connected by the inter‐cerebral commissure. The pleuro‐parieto‐visceral ganglion mass consists of the three ganglion groups suggested by its name. The pedal ganglion mass consists of the ventral of the three masses and consists of the two large pedal ganglia. The distribution of the cell groups, the sizes of the cells in the different groups and the location of the interganglionic connections are described for the three ganglion masses and also for the buccal and digitated optic ganglia. A brief description of the production of paraldehyde‐fuchsin positive neurosecretion in the nerve cells and also a summary of histochemical tests carried out on the cytoplasmic inclusions of the neurons are given.
Rubro‐cerebellar connections in the cat: An experimental study with silver impregnation methods
Authors: Courville J. , Brodal A. 
Published: January 2005

AbstractThe rubro‐cerebellar projection has been studied in the cat with the methods of Nauta and Glees following stereotactically placed lesions in the red nucleus. A description of the intracerebellar nuclei is given in which an attempt has been made to define precisely the limits of each nucleus. The rubro‐cerebellar fibers terminate in the contralateral nucleus interpositus anterior (NIA). It cannot be decided whether the nucleus interpositus posterior (NIP) receives some fibers, but no fibers pass to the medical and lateral nuclei. A somatotopical pattern appears to be present in the projection. Rubrocerebellar fibers are thin and probably terminate in the neuropil. This fiber system is the only direct link known between the red nucleus and the cerebellum. The total number of fibers is small. Probably the fibers are collaterals from the rubrospinal tract fibers and subserve a feedback function between the red nucleus and the cerebellum.
Temporal relationship between myelinogenesis and the appearance of a basic protein in the spinal cord of the white rat
Authors: Kornguth S. E. , Anderson J. W. , Scott G. 
Published: January 2005

AbstractIn a previous study a low molecular weight basic protein, isolated from guinea pig brain, was shown to be localized in the myelin of adult nervous tissue. An antigenically similar protein was present in the central nervous system of a variety of mammals, the chicken and the frog. In the present study, the ability of the nervous system of the albino rat to react specifically with the fluorescent anti‐basic protein antibody was investigated during fetal and postnatal development. Although earlier stages were examined, the spinal cord of the rat was first observed to react with the antiserum in the twenty‐first day of gestation. Ultrastructural studies indicated that well formed myelin, and mature and immature synapses were present in the cervical cord at this time. A positive immune reaction was detected two days before a noticeable Weigert reaction was obtained; the sequence and spatial pattern of labeling with both techniques was similar, however. It was observed that the nucleolus and cytoplasmic web of dorsal root ganglion cells first reacted with the antiserum at a time immediately preceding the onset of rapid myelination of axonal fibers in the ganglion. The immune reaction in the cell body of the large ganglion cells diminished rapidly with the cessation of rapid myelination. The relationship of the findings to the present concept of myelinogenesis is discussed.
Relationship of cortico‐spinal tract growth to age and body weight in the rat
Authors: Bernstein Jerald J. 
Published: January 2005

AbstractThe capacity of neurons of the central nervous system to grow throughout an animal's life has been a subject of continuing interest. Studies were undertaken in rat to ascertain if nerve fibers of the dorsal funicular cortico‐spinal tract increase in diameter and/or number during the animal's growth.Animals were divided into four experimental groups: (a) 4‐weeks, 156 gm; (b) 10‐weeks, 181 gm; (c) 10‐weeks, 281 gm; (d) 9–months, 563 gm. Spinal cords were fixed by perfusion with 2.5% glutaraldehyde and the eighth thoracic segment immersed in 1% osmic acid. Counts and size measurements were made from photomicrographs of 2 μ sections.The average number of myelinated nerve fibers in the tract was 13,723. There were no statistical differences in number of fibers between the various age and weight groups. Growth in this tract was related to increased fiber diameter with age concomitant with increased area of tract and of spinal cord. As the diameter of individual nerve fibers increased, myelin sheath and axis cylinder diameters increased proportionately.The cortico‐spinal tract of the rat grows by increase in nerve fiber diameter from 4‐weeks to at least 9‐months of age. It is suggested that by means of this mechanism of central nervous system growth, the nerve fiber can transmit information at a more rapid rate over greater distances as growth proceeds, thus allowing for sensory and motor coordination of the animal during changes in body size.
The nucleus ambiguus of the rabbit
Authors: Lawn A. M. 
Published: January 2005

AbstractEach nucleus ambiguus of the rabbit contains about 1,500 cells and is approximately 4 to 5 mm long. The author confirms the previously described division of the nucleus into a rostral compact formation, 1.6 mm long, and a caudal diffuse formation occupying the remainder of the nucleus. He further subdivides the compact formation into a lateral part, the principal column, and a medial part, the medial column. These divisions and the cytological differences between the cells in different divisions are illustrated. The cells in the medial column are more similar in appearance to those of the diffuse formation, with which they probably form a continuous column, than to those of the principal column, which are smaller, and have less distinct Nissl granules.
Distal retraction balls in the neurohypophysis after transection of the pituitary stalk
Authors: Daniel Peter Maxwell , Prichard Marjorie Mabel Lucy 
Published: January 2005

AbstractDuring the first few weeks after transaction of the pituitary stalk retraction balls (Cajal) were found on the fibers of the hypothalamo‐neurohypophyseal nerve tract not only above but also in large numbers below the level at which the nerve tract had been cut. The latter, termed distal retraction balls, are clearly seen in routinely stained sections but are even more conspicuous after impregnation with silver. Distal retraction balls were found in the isolated neurohypophysis of man, monkey, goat and sheep. It is suggested that the development of so many retraction balls distal to the site at which the nerve tract had been severed was due largely to conditions resulting from the peculiar anatomical arrangements of the pituitary gland. Stalk section causes infarction and consequent swelling of pars distalis; this swelling, occurring in the confined space of the pituitary fossa, compresses the neurohypophysis, thereby squeezing out axoplasm from the cut ends of the isolated nerve fibers to form the distal retraction balls. Distal retraction balls were not identified with certainty in the rat, possibly because in this species the pituitary gland is not enclosed in a bony fossa, and the neurohypophysis is therefore not compressed when pars distalis swells.
Organization of the spino‐cervico‐thalamic system
Authors: Ha Hongchien , Liu Chan‐Nao 
Published: January 2005

AbstractIn addition to the classical spino‐thalamic and medial lemniscal systems in mammals, there is a spino‐cervico‐thalamic system relayed by the nucleus cervicalis lateralis. This nucleus is a well defined nucleus situated in the lateral funiculus, ventrolateral to the dorsal horn. It is a slender cell column, extending from the lower portion of the medulla through the upper two cervical segments of the spinal cord of the cat as well as some other mammals including primates.Experimental studies have shown that the nucleus cervicalis lateralis serves as a second relay nucleus, projecting to the ventral posterior lateral nucleus of contralateral thalamus. It receives impulses from dorsal root fibers via three different first relay nuclei, namely, Clarke's column, ventral spinocerebellar tract neurons, and the large‐sized neurons in dorsal horn of lower lumbar through sacral segments.The morphology of neurons of the nucleus cervicalis lateralis is unique. The dendrites are well confined in the nucleus and most of them run in the longitudinal direction. Golgi studies revealed the collaterals from dorsal portion of the lateral funiculus to the nucleus. Three types of terminals, namely, bouton of passage, terminal clusters and basket‐like terminals, were found in this nucleus.
The neurohistology of quiescent mammary tissue in Lepus albus
Authors: Ballantyne Bryan , Bunch G. A. 
Published: January 2005

AbstractThe neurohistology of quiescent mammary tissue from adult female albino rabbits was investigated by cholinesterase histochemistry.Dense plexuses of nerve fibers enter the nipple in the dermis surrounding the lactiferous ducts, and unite at the summit of the nipple to form an apical plexus. From the plexuses at the base of the nipple nerves pass between deep epidermal invaginations, to form a basal nipple sub‐epidermal plexus, A sub‐epidermal plexus of fibers of small diameter arises from the apical dermal plexus. At the base of the nipple extensive nerve plexuses occur around smooth muscle. The only endings are intraepidermal nerve terminals from the apical sub‐epidermal plexus. In mammary skin outside the nipple area the dermal and sub‐epidermal plexuses are more attenuated. Longitudinally or circularly arranged nerves occur around hair follicles. Peri‐arterial plexuses are present throughout the mammary tissue. The myo‐epithelial cells and alveoli are not innervated.The neurohistological pattern suggests a spatio‐temporal sensory innervation concerned in neurohormonal reflexes of milk secretion and ejection, and neural reflexes of nipple erection. Autonomic motor innervation regulates blood flow and promotes nipple erection. The absence of myo‐epithelial cell and alveolar innervation indicates a solely endocrine effector regulation of milk ejection and secretion.
Neuroglial relationships in the thoracic ganglion of the fiddler crab, Uca
Authors: Malzone W. F. , Collins G. H. , Cowden R. R. 
Published: January 2005

AbstractA cytological and ultras Uitasructural investigation was undertaken on the thoracic ganglion of the fiddler crab Uca sp., in an attempt to find morphological evidence for functional relationships between neurons and extraneuronal cells.Neurons of several sizes and four types of extraneuronal cells were present in this tissue. These included capsular cells intimately associated with neurons and “endothelial cells” closely associated with a complex branching vascular system. The vascular system ramifies with vessels which decrease in diameter, terminating in extravasculax spaces in intimate contact with the capsular cells. The findings suggest that extraneuronal cells mediate between the vascular system and the metabolically active neurons via modifications which include: (1) A complex branching vascular system, (2) perivascular processes containing numerous clumped mitochondria and complex arrangements of 200 Å spaces between cytoplasmic islands; (3) a parallel array of canalicular elements within capsular cell processes; (4) multicomponent bodies found in several locations including the cytoplasm of extraneuronal cells and the neuronal cytoplasm. These findings support the hypothesis that extraneuronal cells transport macromolecular materials and are thus involved in meeting the metabolic requirements of neurons.
Electrophysiological characteristics of tectal and thalamo‐cortical divisions of the visual system in lower vertebrates
Authors: Karamian A. I. , Vesselkin N. P. , Belekhova M. G. , Zagorulko T. M. 
Published: January 2005

AbstractElectrophysiological characteristics of the visual system have been investigated on an ascending phylogenetic scale in submammalian vertebrates. In cyclostomes and plagiostomes the only system of vision is retino‐tectal. In lampreys spread of excitation from visual centers to descending paths of the spinal cord occurs readily, as a manifestation of diffuse, primitive brain. As a result of progressive cephalization, a new retino‐thalamo‐cortical system arises in amphibia and reptilia. The retino‐tectal system, however, retains its leading role. Optic tectum visual potentials are of short latency, displaying stability of pattern and aptitude to reproduce stimulation rhythm, making them comparable to primary responses of the mammalian cortex. The phylogenetically more recent retino‐thalamocortical system has not attained structural or functional maturity. Due to its diffuse organization, visual potentials generated in the surface cortical layer are of long latency, displaying aptitude to fatigue and recruiting on rhythmical stimulation, sensitivity to nembutal; being unlike the primary responses of the mammalian cortex, they should rather be regarded as responses of a non‐specific type. Electrical stimulation of dorsal thalamic structures in the frog, turtle and varanus also fails to evoke cortical responses of a primary type. In the course of phylogenetic development, the retino‐thalamo‐cortical system evidently goes through a stage (amphibia, reptiles), when representation of the function of vision is of a mainly non‐specific nature.
The number of nerve cells in the cerebral cortex of man
Authors: Pakkenberg Henning 
Published: January 2005

AbstractIn a normal brain fixed by perfusion, the number of nerve cells in the cortex was determined by counting the nucleoli in sections of measured thickness. The Abercrombie correction formula was used, and a mean value obtained of 17,560 cells per mm3. The linear shrinkage was determined in three other brains, both after fixation in alcohol‐formalin and after paraffin embedding and sectioning. A 20% shrinkage in volume was found after fixation, and a 74% shrinkage in volume after the histological procedures. Reckoning with a cortex volume of 570 ml in the unfixed brain, the total number of nerve cells in the cortex examined is found to be 2.6 × 109 cells.
Cell frequencies in the human inferior olivary nuclear complex
Authors: Moatamed Farhad 
Published: January 2005

AbstractCerebellar afferents from the inferior olivary nuclei arise from about one million nerve cells. This figure was determined by counts and estimates carried out on four complete series of human brain‐stem sections of a new‐born, a three‐month‐old infant, a 42‐year‐old male and a 56‐year‐old male. Cell frequencies in all four cases were nearly identical. About 7% of this total belongs to the two accessory nuclei, believed to project to the archeocerebellar cortex.Cell sizes differ between the main and the two accessory olivary nuclei, the former having a mean cell size of about 400 μ2, the latter about half this size. Comparing infant and adult cell size, there is a threefold increase in volume from infancy to adulthood. Packing density of nerve cells in the infants is about twice that of the adults. The ratio of nerve cells to glia cells is 1:4 in the adults and 1:6.7 in the infants.
Magnocellular neurosecretory centers in the rat hypothalamus
Authors: Price Peterson R. 
Published: January 2005

AbstractHypothalami from normal rats were examined after preparation with Gomori's chromalum‐hematoxylin stain for neurosecretory material. In addition to the supraoptic and paraventricular nucleii, five additional nuclear masses of neurosecretory cells were found. These all formed more or less compact cellular groups, clearly demarcated from surrounding neural tissue and with constant location from animal to animal. One nucleus, immediately posterior to the anterior commissure, along the ventricular wall, is termed anterior commissural. Two others, being dorso‐lateral to the columns of the fornix, are termed anterior and posterior fornical. Midway between the paraventricular nucleus and the optic tract, a characteristically shaped nucleus of very compact cells, the nucleus circularis, is encountered. Finally, another group of cells is seen dorsal to the optic tract in the middle of the medial forebrain bundle, the nucleus of the medial forebrain bundle.
The neuronal components of the optic nerve of the crayfish as studied by single unit analysis
Authors: Wiersma C. A. G. , Yamaguchi T. 
Published: January 2005

AbstractUnit responses were obtained from the optic nerve of the crayfish, Procambarus clarki (Girard) with steel needles. Eighty‐three repeatedly recognized elements are described. They range from bundles of primary sensory fiber to complexly reacting multimodal interneurons. Visually reacting fibers fall into two main classes, one class reacts tonically to overall illumination, the other responds to moving objects. Sustaining fibers react to increased light with increased output, dimming fibers are active in the dark and inhibited by light. Fourteen sustaining and four dimming fibers are described. The main movement fiber type, of which eleven have been found, responds to shadows. They “habituate” quickly and react best to movement of small black objects. All these fibers, and some others, are present as centrifugal elements from the other eye. All these fibers, and some others, are present as centrifugal elements from the other eye. Four fibers, two sustaining and two movement ones, change their fields with positions of the animal. These “space‐constant” fibers “look” at the sky from all positions for which possible and are otherwise “blind.” Mechanoreceptive interneurons form a bundle between the first and second classes of optical fibers. Seventeen members are described. Five multimodal fibers, with combined visual and mechanoreceptor input are described. Maps of the approximate locations of the units in the cross‐section of the optic nerve are presented. The number of times specific fibers were found exceeded 50 for 28.
The distribution of the internal carotid circulation in the brain of the macaque monkey (Macaca mulatta)
Authors: Coceani F. , Gloor P. 
Published: January 2005

AbstractThe distribution of the internal carotid circulation of the macaque brain was studied by using a method of intracarotid dye injections which produced no appreciable disturbance of the dynamics of the cerebral circulation. The areas in cortical and diencephalic structures supplied by the carotid circulation are described and displayed semidiagrammatically in a set of figures. The carotid artery supplies most of the lateral and mesial surfaces of the cerebral hemisphere, whereas the hemispherical portion supplied by the posterior cerebral artery is confined to the occipital and inferior temporal region. Left and right internal carotid territories overlap widely across the midline in cortical areas due to the existence of a single pericallosal arterial trunk formed by the junction of both anterior cerebral arteries. In the diencephalon the segregation of the territories of the left and right internal carotid arteries is sharp, except in its anterior‐most portion. The pattern of internal carotid supply to the thalamus is somewhat variable, the most lateral structures are most consistently supplied by this vessel, whereas the more medial structures, even those lying far rostral within the thalamus, are supplied by the posterior cerebral artery. The territories of the two vessels overlap considerably within the thalamus. In a certain number of animals, the posterior cerebral artery is part of the internal carotid, rather than of the vertebral‐basilar system.
The cytoarchitecture of the brain stem of the domestic pig
Authors: Breazile James E. 
Published: January 2005

AbstractThe cytoarchitecture and topography of some brain stem nuclei of the pig have been studied intransversely and sagitally cut, Nissl and Weigert stained, semiserial section. The cytology of those brain stem nuclei which receive an afferent supply from the ventrolateral funculus of the spinal cord is described. This study was found to be a necessary prologue to the study of distribution and terminations of spinal cord afferents to the brain stem in this species.The recognition of a nuclear pattern within the brain stem of the pig which is quite similar to that described in other species is noted.