bluuebunny/crossref_metadata_2025_split huggingface dataset:
Brain sizes, surfaces, and neuronal sizes of the cortex cerebri: A stereological investigation of man and his variability and a comparison with some mammals (primates, whales, marsupials, insectivores, and one elephant)
Authors: Haug Herbert 
Published: February 2005

AbstractThis study deals with the stereological estimation of macroscopic sizes of brain and cortex, i. e., volume, surface, and folding, and of microscopic neuronal sizes, i. e., density, mean size, size distribution and number of neurons. The results show that the degree of variability in man amounts to about 15%. A decrease in volume of the different gray structures can be observed in man after the age of 65 years. The surface, folding index, and length of convolution do not alter with aging. The comparison with mammals of various sizes allows the conclusion that there is a high correlation to brain size for nearly all macroscopic values. Man and elephant, however, have a cortical surface which is, in comparison with whales, relatively small. In contrast, whales have very small cortices compared with man.At the cytoarchitectonic level, the neuronal density has a correlation to brain size. Contrary to other mammals, the primates and man have a high fraction of small granular neurons, especially in layer 4. The assumption that the number of cortical neurons beneath a given surface area of cortex is the same in all mammals cannot be verified, especially in those with large brains. The allometric connection between brain size and parameters is not valid for all measurements (e. g., thickness of cortex, mean size of neurons, perikaryal size distribution, and glial density). Yet some other measurements are well correlated.
Properties and purification of a colony‐stimulating factor of granulocytes and macrophages produced by mouse spleen cells
Authors: Chou Robin H. , Chen Thelma A. , Chou Koulin L. , Amenta Peter S. 
Published: February 2005

AbstractMouse splenocytes are induced by pokeweed mitogen to secrete a factor that stimulates mouse hemopoetic (spelling per Nomina Histologica in the Nomina Anatomica, 5th edition, 1983, Williams and Wilkins, Baltimore) progenitor cells to undergo proliferation and differentiation into granulocytes and macrophages in a semi‐solid culture system. The granulocyte and macrophage colony‐stimulating factor (GM‐CSF) was purified with a four‐step procedure that includes ultrafiltration, chromatography on DEAE‐agarose, Sephacryl S‐200, and chromatofocusing gel. The isoelectric point (pI) of 4.2 of the GM‐CSF was determined by analytical isoelectrofocusing gel electrophoresis. The sensitivity of the biological activity of GM‐CSF to digestion by trypsin and neuraminidase suggests that GM‐CSF is a glycoprotein with its sugar moieties at the active site. The GM‐CSF is also sensitive to heat denaturation at 60°C or higher suggesting that a three‐dimensional conformation is required for its biological activity. The molecular w eight of GM‐CSF is approximately 57,000 Daltons as determined by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate.
Early development of the facial nerve in the chick embryo with special reference to the development of the chorda tympani
Authors: Kuratani Shigeru , Tanaka Shigenori , Ishikawa Yuji , Zukeran Chosei 
Published: February 2005

AbstractThe development of the facial nerve from Hamburger and Hamilton stage 17 to stage 28 is described in chick embryos by means of a new immunochemical nerve staining method that uses an antineurofilament protein (NFP) antibody. A postspiracular branch and an unknown transient posterior branch beneath the ostocyst were observed at stage 17. At stage 19, the primordia of the r. palatinus were observed. A prespiracular branch appeared at stage 21, and with the postspiracular nerve, it made a loop encircling the spiracle (spiracular loop). The first primordium of the ramus (r) hyoideus and transient rami (rr) dorsales appeared around stage 23. At stage 25, the chorda tympani was first observed to arise from the ventral end of the spiracular loop. At stage 26, a communicating branch, connexus cum nervo glossopharyngeo, was found along with the vena (v) capitis lateralis.The rr. dorsales seemed to represent the r. supratemporalis in lower animals. The communicating branches around the v. capitis lateralis seemed to correspond to the cutaneous nerve communications between the branchial nerves frequently encountered in Amphibia.It was found that the chorda tympani becomes a prespiracular nerve for the most part in the chick by the reduction of the postspiracular component of the spiracular loop. Thus, the nerve differs markedly from that in other animals, which is postspiracular. This difference explains the different passage of this nerve in the chick as compared with other amniotes.
The interdependence of the follicular, parafollicular, and mast cells in the mammalian thyroid gland: A review and a synthesis
Authors: Kališnik M. , Vraspir‐Porenta O. , Kham‐Lindtner T. , Logonder‐Mlinšek M. , Pajer Z. , Štiblar‐Martinčič D. , Zorc‐Pleskovič R. , Trobina M. 
Published: February 2005

AbstractThe aim of this paper is to summarize some of our quantitative descriptive and experimental studies, to discuss them in view of the literature data, and to present a synthesis of the topic.The results of stereological analysis of some tissue components of the rat thyroid gland have been compared with the results of topological studies on the parafollicular cells of various mammalian species. Localization of the parafollicular cells in the central regions of the thyroid gland lobes, where the follicular cell activity seems to be greater than in the periphery of the lobes, has led to the hypothesis that the parafollicular cells regulate (stimulate and/or suppress) the activity of the follicular cells.Long‐term application and antithyroid drugs to mice and rats has shown that excessive concentrations of thyrotropin provoke hyperplashia of both the follicular cells and the intrathyroid mast cells and, transiently, of the parafollicular cells. This and some of the literature data are congruent with the hypothesis that the parafollicular and mast cells also stimulate the follicular cells by their paracrine secretions.Long‐term application of antithyroid drugs to mice and rats has shown that excessive concentrations of cular cells but also probably stimulation of the follicular cells, as judged by the stereological measurements.The biological meaning of the spatial integration of follicular and parafollicular cells seems to be a functional coordination of both epithelial cell lines, supported by intrathyroid mast cells.
Characterization of the morphological, growth, and steroidogenic effect of TPA on mouse Y‐1 adrenal cortical tumor cells in culture
Authors: Murray Sandra A. , Polizotto Sandra 
Published: February 2005

AbstractThe tumor‐promoting agent 12–0‐telradecanoyl‐phorbol‐13‐acetate (TPA) caused a time‐ and dose‐ dependent morphological change in Y‐1 adrenocortical tumor cells. The morphological alteration was apparent 2 hr following addition of 1 μg/ml TPA cell cultures and became more striking with longer treatment times. Smaller doses of TPA took a longer time to produce an effect. Cultures grown in the presence of TPA exhibited more rounding and piling up cells than similar cultures maintained in medium lacking TPA. These TPA‐stimulated morphological changes were reversible, and after 24 hr in TPA‐free media, cultured cells began to flatten. After 96 hr in TPA‐media they resembled the control cultures. The reversibility of the morphological change was also dose dependent: cells treated with 1 μg/ml TPA took a longer time to resume the typical control morphology than cultures treated with 0.01 μg/ml TPA. In addition, TPA treatment resulted in a decrease in cell growth rate, an increase in steroid production, and an increase in localization of free catalytic units of cAMP‐dependent protein kinase in the cytoplasm. The steroidogenic effect of ACTH on the cell population was inhibited cultures maintained in TPA. The results of this study indicate that TPA induces morphological changes the Y‐1 adrenocortical tumor cell population while increasing steroidogenesis and the activation of cAMP‐dependent protein kinase and decreasing cell growth rate.
Changes with senescence in the fine structure of the granular convoluted tubule of the submandibular gland of the mouse
Authors: Gresik Edward W. 
Published: February 2005

AbstractCells of the granular convoluted tubules (GCTs) of the submandibular glands of senescent male mice show structural changes indicative of functional decline. In order to define the nature of these age‐related changes more clearly, the fine structure of GCT cells of 12‐ and 28‐month‐old males was compared. In old mice, there was cell‐to‐cell variation in the extent of these changes, with some cells of senescent males appearing no different from those of young adults. In affected cells the most striking alterations were seen in secretion granules and lysosomal elements. Secretion granules varied greatly in size, with some GCT cells having only very fine apical granules. Secondary lysosomes and large lipofuscin granules were frequent in the basal cytoplasm. Very large dense bodies (3‐5 μm) occurred in many cells. These possibly represent intracellular pools of released secretory materials, as they were occasionally seen in continuity with the luminal contents. Structures whose appearance was intermediate between the very large dense bodies and lipofuscin granules were common, suggesting crinophagic activity. There was an apparent decrease in numbers of polysomes and in the extent of the Golgi apparatus. These fine structural changes are consistent with impairments with advanced age in synthesis and posttranslational processing of secretory products by affected GCT cells. In addition to cell‐to‐cell variation in any one male, there was also interanimal variation in the degree and extent of these senescent changes.
Anatomy of the cruciate ligaments and their function in extension and flexion of the human knee joint
Authors: Fuss Franz K. 
Published: February 2005

AbstractThe areas of the femoral origin of the cruciate ligaments have approximately the shape of sectors of ellipses, the one for the anterior ligament on the lateral condyle posteroproximally and the one for the posterior ligament on the medial condyle distally. By means of a new technique of dissection, combined with the use of X‐rays, the change in distance between the origin and insertion and so the change of tension of single bundles of the ligaments could be analyzed. Only a rather thin bundle in each cruciate ligament is in constant tension: “guiding bundles.” The maximal diminution of distance between the origin and insertion for some bundles is 65%. In the anterior cruciate ligament the majority of fibers are taut in extreme extension: “limiting bundles.” The same is true in the posterior cruciate ligament in extreme flexion. There are also some fibers, especially in the posterior cruciate ligament, that are taut only in an intermediate position. The geometric analysis of the function of different groups of fibers was performed by a modification of Menschik's concept of a four‐bar link.
Immunohistochemical and ultrastructural study of human melanoma colonies grown in soft agar
Authors: Persky Bruce , Meyskens Frank L. , Hendrix Mary J. C. 
Published: February 2005

AbstractAn immunohistochemical and ultrastructural study of human melanoma colonies grown in soft agar for up to 50 days was performed. Three morphological variants of developing tumor colonies are reported: (1) large light colonies, (2) small dark colonies, and (3) smooth‐edged colonies. The large light colony variant is the most frequently observed in the soft agar assay (≈︁70%), followed by the dark colony variant (≈︁27%), and the smooth‐edged colony variant (≈︁3%). Major morphological characteristics are associated with each variant, as shown with light microscopy (LM) and transmission electron microscopy (TEM). Both LM and TEM analyses demonstrated that the large light colony variant was hypomelanotic and contained a microfibrillar extracellular matrix (ECM). The small dark colony variant was found to be hypermelanotic and contained a less demonstrable ECM. The smooth‐edged variant has an encapsulated periphery, no demonstrable ECM, and tightly packed cells with desmosome‐like junctions. In order to characterize further the ECM in the most commonly observed variant, the large light colony, specific antibodies to fibronectin (FN) and collagen types IV and V (COLs IV and V) were applied and observed with immunofluorescence microscopy and immu‐noperoxidase. In paraffin sections of melanoma colonies, FN was observed associated with both the cell surface and the ECM. However, no specific staining was seen for COLs IV and V. In addition, ruthenium red was used to preserve and selectively bind to glycosaminoglycans (GAGs) and proteoglycans (PGs). TEM studies reveal GAG‐like granules stained with ruthenium red in the fibrillar ECM and a dotted, punctate staining of the cell surface. Understanding the biological and architectural composition of developing melanoma tumor colonies in soft agar could contribute to the development of more efficient chemo‐therapeutic strategies.
Quantitative morphology of the central fovea in the primate retina
Authors: Krebs Wolf , Krebs Ingeborg P. 
Published: February 2005

AbstractElectron micrograph composites of tangential sections of the fovea centralis of three cynomolgus monkeys (Macaco, irus) and one baboon (Papio anubis) were used to determine the spatial density of the principal retinal cells. In the center of the foveola, the density of cones ranged from 113,000 to 230,000/mm2, and pigment epithelial cells from 4,900 to 7,000/mm2. At a distance of 500μm from the foveolar center the density of the cone cell pedicles ranged from 29,000 to 36,300/mm2, and the density of horizontal cells ranged from 19,000 to 25,100/mm2. Densities of bipolar, Muller, and amacrine cells were determined in only two monkeys and in the baboon.The fact that the cone cell pedicles have a larger diameter than the foveolar cones explains the geometry of the fovea. The morphology of the junction between foveolar cone outer segments and the pigment epithelium reflects the complex metabolism of this functional unit. The comparison with the peripheral primate retina suggests that the densities of horizontal and bipolar cells, but not of amacrine and Muller cells, are correlated with the density of cone cell pedicles.
Epithelial cytodifferentiation and extracellular matrix formation in enamel‐free areas of the occlusal cusp during development of mouse molars: Light and electron microscopic studies
Authors: Sakakura Yasunori , Fujiwara Naoki , Nawa Tokio 
Published: February 2005

AbstractMandibular first molars in mice ranging in age from 18 days prenatal to 5 days postnatal were used for light and electron microscopic examinations of the enamel‐free area (EFA) during development of the occlusal cusp (mesiobuccal cusp). Notable morphological changes in the inner enamel epithelium and the cells of the stratum intermedium were observed. At prenatal age of 18 days, the inner enamel epithelium of the EFA (EFA epithelium) was composed of a layer of columnar cells and covered by the cells of the stratum intermedium. Two days after birth, the EFA epithelium was made up largely of preameloblasts, with mitochondria located in the proximal side of the cells toward the stratum intermedium. The cells of the stratum intermedium were irregularly shaped, with wide intercellular spaces between them. At a postnatal age of 3 days, most of the EFA epithelial cells resembled maturation‐stage ameloblasts, being short and columnar in shape and having nuclei located in their proximal side. Distal cell membranes were folded, and mitochondria were scattered throughout the cytoplasm. In 4‐day‐old mice, the EFA epithelium was found to be formed of short columnar or cuboidal cells with distinct intercellular spaces. The cells of the stratum intermedium could no longer be detected, and cells of the EFA epithelium could not be distinguished from those of the stellate reticulum. Odontoblasts of the EFA were arranged and polarized parallel to the basal lamina, and odontoblastic processes extended toward the cusp tip. The orientation of thin and thick collagen fibers within predentin and dentin was also parallel to the basal lamina. Even after dentin mineraliza tion, disrupted basal lamina and long, aperiodic, fine fibrils were found between the epithelium and the dentin. Following the disappearance of the basal lamina and fine fibrils, stippled material and crystals appeared on the dentin surface. The mineralized matrix, which x‐ray microanalytical energy peaks identified as containing calcium and phosphorus, was continuous with enamel in the distal slope of the cusp at the cusp tip. Thus, the inner enamel epithelium of the EFA differentiated into secretory cells capable of enamel‐like matrix formation. In conclusion, development of EFA in mouse molars seems to be a system suitable for use in studying both the involvement of extracellular matrix, including basal lamina constituents, in ameioblast differentiation, and the role of the cells of the stratum intermedium, together with the ameloblasts, in comprising a single functional unit responsible for enamel formation.
Light and electron microscopy studies of the ulnar, saphenous, and caudal cutaneous sural nerves of the dog
Authors: Illanes O. , Henry Julie , Skerritt G. 
Published: February 2005

AbstractTransverse sections of the ulnar, saphenous, and sural nerves taken at specific levels in normal, young‐adult beagle dogs were examined qualitatively and quantitatively at both the light and electron microscopic levels. The aim of this investigation was to provide baseline information for future studies of peripheral nervedisease in this species. A systematic sampling technique was used for the determination of nerve components (i.e., unmyelinated axons and Schwann cell and fibroblast nuclei). In all nerves sampled, the average size distribution for unmyelinated axons was unimodal, and most of the axons were 0.4–1.1 μm in diameter. Within this range, there were slight individual and nerve‐to‐nerve variations in the location of the largest diameter peak. The mean densities of Schwann cell nuclei (numbers/mm2) ranged from 841/mm2 in the palmar branch of the ulnar nerve, to 1,223/mm2 in the caudal cutaneous sural nerve, being nearly four times the average density or fibroblast nuclei.In every animal and in almost every nerve, a few abnormalities were found; and these should be kept in mind when assessing peripheral nerves in the dog.
Variations in atrioventricular valve innervation in four species of mammals
Authors: Williams Terence H. , Folan Jean C. , Jew Jean Y. , Wang Yan‐Feng 
Published: February 2005

AbstractIn this series of studies, the innervation patterns of whole‐mount preparation of bicuspid and tricuspid valves were studied by light microscopy in the mouse, rat, guinea pig, and opossum. The acetylcholinesterase‐positive networks of nerve fibers showed many similarities in the basic patterns of valve innervation in all of the species studied, but several interspecies variations were observed. The basal zone of the valve adjacent to the fibromuscular atrioventricular ring displayed the most dense plexus of nerves, with acetylcholinesterase‐positive fibers being seen across the width of the valve. In the intermediate zone of the valve, less dense plexuses of nerve fibers were found; and these were more numerous in the cuspal areas and less numerous in the intervening commissural areas. In the distal portions of the valve, nerve networks arborized extensively, with some of their nerve fibers extending toward the chordae tendineae and the free edges of the valve cusps. Only in the guinea pig and opossum did these fibers reach the free margin of the valve cusp, where they either ended directly as free nerve endings or lay parallel to the free edge of the cusp, often running between adjacent chordae tendineae. Although the patterns of innervation were similar in both bicuspid and tricuspid valves, the innervation density of the bicuspid valve was greater than that of the tricuspid valve for each species examined.A distinguishing feature of guinea pig and opossum tricuspid valves was that their chordae tendineae were relatively more prominent and more densely innervated than the bicuspid chordae tendineae. Free nerve endings with no light microscopic evidence of specialization were present throughout the bicuspid and tricuspid valves of all species studied. Some nerve endings in the opossum showed evidence of specialization, with brush‐like arborizations leading to presumed free terminals seen chiefly in the distal zone of the valve cusps. Although some general tendencies were apparent, we have demonstrated that interspecies heterogeneity exists in the terminal networks of the atrioventricular valves of mouse, rat, guinea pig, and opposum.In spite of the questions raised regarding the significance of valve innervation in light of the success of valve prostheses, there is relatively high morbidity and mortality associated with heart valve replacement, partly due to deterioration in ventricular function. We and other investigators have reported that valvar nerves extend to the chordae and papillary muscles, varying with valve and species.This anatomical information about normal valves helps to lay the foundation for future studies of the role of valve innervation in the regulation of cardiac function and dysfunction. Such knowledge should be applicable for the control and management of myocardial infarction, valve disease, valve replacement, valvuloplasty, cardiac transplantation, administration of drugs, etc.