bluuebunny/crossref_metadata_2025_split huggingface dataset:
Immunogold labelling of leukemic hairy cells with the B‐ly7 monoclonal antibody: An SEM and TEM study
Authors: de Harven Etienne , Christensen Hilary , Poppema Sibrand , Scott J. Gerald 
Published: February 2005

AbstractTwo cases of hairy cell leukemia have been studied by immuno‐TEM and immuno‐SEM after immunogold labelling of the cell surface antigen recognized by the B‐ly7 monoclonal antibody.Most hairy cells appeared significantly labeled, although the density of the expression of the antigen, as demonstrated by immunogold labelling, seems variable from cell to cell. Moreover, some cells with the morphology of hairy cells and which could not be identified as monocytes were not labeled. Labelling for the antigen identified by the B‐ly7 mAb does not seem to correlate with the presence of ribosome lamellae complexes which were present only in one of the two cases studied. Rare lymphocytes of unidentified lineage were labeled. Monocytes were significantly absent from the samples of peripheral blood of the two patients studied. In one normal control sample, monocytes were observed unlabelled.The results are discussed in reference to the pathogenesis of hairy cell leukemia, its surprisingly low mitotic rate, and its distinct response to chemotherapy. © 1994 Wiley‐Liss, Inc.
Structure and function of cartilage collagens
Authors: Bruckner Peter , van der Rest Michel 
Published: February 2005

AbstractCollagens are the major proteinaceous constituents of cartilage. Three collagen types participate in the formation of striated fibrils of cartilage, collagens II, IX, and XI. Collagen II and XI belong to the subgroup of fibrillar collagens and are structurally closely related, differing mainly in their N‐propeptides. Collagen IX has a very different structure but is nevertheless an essential constituent of the striated fibrils. Two other collagen types are also found in cartilage but form distinct structures. Collagen VI, found mainly in the periphery of the chondrocytes, forms beaded filaments. These filaments are probably formed by interaction of collagen VI with hyaluronan. Collagen X is expressed by hypertrophic chondrocytes. It has been shown to form in vitro hexagonal lattices and in vivo to be associated either with striated fibrils or with mats which may correspond to the lattices. The functional role of the collagen diversity in cartilage is discussed. © 1994 Wiley‐Liss, Inc.
Image analysis of the extracellular matrix
Authors: Arsenault A. Larry , Kohler Derek M. 
Published: February 2005

AbstractThe epiphyseal growth plate and articular cartilage matrices were preserved by slam freezing and freeze substitution to optimally retain the native organization for both cellular and matrix components. These specimens were stained and examined using conventional electron microscopic methods. The highly integrated, proteoglycan‐rich matrices were examined by computer image analysis using such parameters as distribution, connectivity, orientation, and a variety of morphometric analyses. Also, different aspects of electron tomography and 3D rendering of matrix vesicles and their associated mineral deposits from epiphyseal growth plates and turkey leg tendons are presented. © 1994 Wiley‐Liss, Inc.
Extraction of second phases from magnesium and aluminum alloys for analytical electron microscopy
Authors: Carpenter G. J. C. , Ng‐Yelim J. , Phaneuf M. W. 
Published: February 2005

AbstractTechniques are described for the extraction onto carbon replicas of precipitates and inclusions from Mg and Al‐based alloys for analytical transmission electron microscopy. EDX analysis of Mn precipitates from a MG‐Mn alloy illustrates the problems that can arise from spurious X‐rays, caused by the use of a 3mm disc specimen. Published 1994 Wiley‐Liss, Inc.
In situ expression of collagen and proteoglycan genes in notochord and during skeletal development and growth
Authors: Sandell Linda J. 
Published: February 2005

AbstractCartilage is an important tissue in skeletogenesis, in the growth of long bones, and as a flexible component of the mature skeleton. The extracellular matrix proteins type II collagen and aggrecan comprise 90% of the matrix and are characteristic of cartilage. Type II collagen provides structural integrity to the tissue, while aggrecan confers resiliency. The quantity of type II procollagen is controlled at the level of transcription of mRNA from the COL2A1 gene. In addition, type II procollagen can be expressed in two isoforms by differential splicing of the primary gene transcript, a post‐transcript, a post‐transcriptional control mechanism. The two mRNAs either include exon 2 (type IIA) or exclude exon 2 (type IIB) which encodes the major portion of the amino (NH2)‐propeptide [Ryan and Sandell (1990), J. Biol. Chem., 265:10334–10339]. The aggrecan gene also encodes alternative splice forms that may be developmentally expressed. The regulation of aggrecan splicing or transcription has not been studied in detail. To determine the spatial and temporal patterns of expression of extracellular matrix in the development of cartilage, we have examined the expression of type II collagen and aggrecan during chondrogenesis in the vertebral column and during elongation of a newborn growth plate. Our results indicate that there is a developmental sequence of type II collagen splice form expression during chondrogenesis with type IIA expressed in prechondrocytes and type IIB expressed in chondrocytes. During elongation of the growth plate, mature chondrocytes express type IIB procollagen and then differentiate into hypertrophic chondrocytes and initiate expression of type X collagen. In all cases, aggrecan was coordinately expressed with type IIB procollagen. As cartilage‐like proteins have been observed in more primitive structures such as notochord, the expression of type II collagen mRNAs was also examined in the notochordal remnants of the vertebral column. In the notochord, the predominant collagen expressed was the type IIA collagen prechondrocyte isoform. Notochordal cells also expressed mRNAs more characteristic of fibroblasts such as versican and decorin: low expression of type I collagen, type IIB collagen, and aggrecan were observed. © 1994 Wiley‐Liss, IncThis Article is a US Government work and, as such, is in the public domain in the United States of America.
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EBIC study of electron generation function in a‐Si:H
Authors: Najar S. , Equer B. 
Published: February 2005

AbstractThe electron beam induced current technique was used to study electron energy loss in amorphous hydrogenated silicon a‐Si:H. This study leads to the determination of the electron generation function which is needed when using the variable energy electron beam induced current technique (EBIC) analysis of a‐Si:H device. A series of identical n‐i‐p a‐Si:H diodes with a thin aluminium top electodes were fabricated and varying thicknesses of a‐Si:H layer were deposited on it. In EBIC measurements, the n‐i‐p diode was reverse biased at maximum potential. The electron range of a‐Si:H was determined directly by measuring the energy at which the electron beam is completely stopped in the top layer and no carrier generation is possible in the n‐i‐p diode. The generation function is then deduced from EBIC contrast measurements between the aluminium electrode and the top a‐Si:H layer. © 1994 Wiley‐Liss, Inc.
Immunohistochemistry of small intensely fluorescent (SIF) cells and of sif cell‐associated nerve fibers in the rat superior cervical ganglion
Authors: Heym Christine , Klimaschewski Lars , Borghini Nadine , Fischer‐Colbrie Reiner 
Published: February 2005

AbstractDouble‐labelling immunofluorescence was applied on single sections of the rat superior cervical ganglion to evaluate neurochemistry and connectivity of intraganglionic SIF cells. The synaptic vesicle membrane protein synaptophysin and secretoneurin, a newly discovered neuropeptide derived from secretogranin II, proved reliable molecular markers of this cell type, whereas serotonin and tyrosine hydroxylase immunoreactivities were observed in slightly incongruent SIF cell subpopulations. Immunolabelling for vasoactive intestinal polypeptide and neuropeptide Y occurred in few SIF cells. None of the above immunoreactivities were visibly altered by preganglionic or postganglionic denervation, while some SIF cells were immunolabelled for galanin or for the neuronal microtubule‐associated protein MAP2 after postganglionic denervation. SIF cells were nonreactive for the pan‐neuronal marker protein gene product (PGP) 9.5 or neurofilament 160 kD. Intense staining of NADPH‐diaphorase in some SIF cells, suggesting catalytic activity of nitric oxide synthase, could not be substantiated by immunoreactivity for this enzyme. SIF cells were approached by nonidentical fiber populations immunoreactive for PGP 9.5, neurofilament, or neuropeptide Y, whereas immunoreactivities for galanin and vasoactive intestinal polypeptide were colocalized in fiber meshes around SIF cells. The findings indicate (1) neurochemical SIF cell heterogeneity, (2) SIF cell plasticity in response to ganglionic perturbation, and (3) a differentiated innervation of SIF cells in the rat superior cervical ganglion. © 1994 Wiley‐Liss, Inc.
Three‐dimensional imaging and image analysis of hippocampal neurons: Confocal and digitally enhanced wide field microscopy
Authors: Turner James N. , Szarowski Donald H. , Turner Todd J. , Ancin Hakan , Lin Wen‐Chieh , Roysam Badrinath , Holmes Timothy J. 
Published: February 2005

AbstractThe microscopy of biological specimens has traditionally been a two‐dimensional imaging method for analyzing what are in reality three‐dimensional (3‐D) objects. This has been a major limitation of the application of one of science's most widely used tools. Nowhere has this limitation been more acute than in neurobiology, which is dominated by the necessity of understanding both large‐and small‐scale 3‐D anatomy. Fortunately, recent advances in optical instrumentation and computational methods have provided the means for retrieving the third dimension, making full 3‐D microscopic imaging possible. Optical designs have concentrated on the confocal imaging mode while computational methods have made 3‐D imaging possible with wide field microscopes using deconvolution methods. This work presents a brief review of these methods, especially as applied to neurobiology, and data using both approaches. Specimens several hundred micrometers thick can be sampled allowing essentially intact neurons to be imaged. These neurons Image analysis in 3‐D is as important as visualization in 3‐D. Automated methods of cell counting and analysis by nuclear detection as well as tracing of individual neurons are presented. © 1994 Wiley‐Liss, Inc.
Quantitative three‐dimensional confocal microscopy of synaptic structures in living brain tissue
Authors: Hosokawa Toshiyuki , Bliss Timothy V. P. , Fine Alan 
Published: February 2005

AbstractIn order to study changes in synaptic structure that accompany learning and memory, we have developed optical methods to visualize dendritic spines and presynaptic terminals in living, electrically monitored brain slices maintained in vitro. Focal microapplication of the fluorescent lipophilic dye DiI provides Golgi‐like staining of small numbers of cells and processes that can be resolved clearly using confocal microscoopy; viability of stained cells is established by exclusion of the fluorescent DNA‐binding dye ethidium bromide. Serial optical sections are enhanced by deconvolution and other image processing methods. The resulting high‐resolution images are combined in an automated procedure to generate three‐dimensional reconstructions, in which submicron synaptic structures can be viewed and measured. These unbiased methods allow volume changes in individual, living synaptic structures to be assessed quantitatively over periods of hours or days in development or in response to stimulation, drug application, or other perturbations. © 1994 Wiley‐Liss, Inc.
Hyaluronate distribution in the regenerating retinal pigment epithelium of the rabbit: A study using confocal laser scanning microscopy
Authors: Korte Gary E. , Moskowitz Leslie , Mrowiec Ewa , Hamou Daniel 
Published: February 2005

AbstractThe distribution of hyaluronate (HA) in regenerating retinal pigment epithelium (RPE) of the rabbit was examined using immunohistochemistry and confocal laser scanning microscopy. The goal was to determine if there is a correlation between differentiation and HA expression, like that seen in developing tissues, where HA accumulates and then disappears as the tissue matures. In normal RPE cells HA is associated mainly with the apical surface. In regenerating RPE (produced by i.v. injection of sodium iodate to damage the epithelium, regeneration arising from spared cells), HA exhibits a patchy distribution among the more immature cells and is especially prominent where they overlap or pile up on each other. Where cells are more mature and form a compact monolayer of cells, HA is expressed mainly on the apical surface, as in normal RPE. The accumulation of HA among the more immature cells in the regenerating epithelial sheet supports the hypothesis that HA influences differentiation by suppressing cell‐cell associations until the proper time for their formation. © 1994 Wiley‐Liss, Inc.
Three‐dimensional organization of neuronal and glial processes: High voltage electron microscopy
Authors: Hama Kiyoshi , Arii Tatsuo , Kosaka Toshio 
Published: February 2005

AbstractNeurons and glia cells in the mammalian central nervous system have many complicated processes. They are too fine for light microscopic study and too complicated and widely spread for thin section electron microscopy. High‐voltage electron microscopic (HVEM) stereo observation of thick Golgi preparation provides detailed 3‐D images of their processes. Three‐dimensional fine structures of astocytic processes in the neuropile and on the surface of neuronal somata, and those of the ruffed cell axon initial segment and thorny excrescences of CA3 pyramidal cell dendrites, are elucidated with the aid of HVEM stereoscopy of thick Golgi preparations. In addition, some results obtained by 3‐D morphometrical analysis of dendritic spines using HVEM stereo images are shown.The examples presented here clearly show the usefulness of high‐voltage electron microscope stereo observation of thick specimens for detailed morphological and morphometric study of the central nervous system. © 1994 Wiley‐Liss, Inc.
Application of serial sectioning and three‐dimensional reconstruction to the study of taste bud ultrastructure and organization
Authors: Royer Suzanne M. , Kinnamon John C. 
Published: February 2005

AbstractThe lingual taste buds of mammals are complex organs containing dozens of cells of varying morphology and numerous nerve fibers that are intermingled among the cellular processes. Some of the taste bud cells form synaptic contacts with these nerve fibers. Important questions remain to be answered regarding the structure and function of the cells of various types within taste buds and the means by which responses to gustatory stimuli are transmitted to the nerve fibers that communicate with the brain. Using both conventional and high voltage electron microscopy, we have examined serially sectioned taste buds from the tongues of mice and rabbits in order to address these issues and to obtain more complete information than that available from sampling of sections. The technique of computer‐assisted 3‐D reconstruction was used to generate models of whole taste buds and individual cellular and neural elements within taste buds from the serial sections.Analysis of serially sectioned taste buds from mice and rabbits has revealed that in both of these species relatively few (30% or less) of the cells within the taste buds form synaptic contacts with nerve fibers. In the foliate taste buds of rabbits, all of the cells that are presynaptic to nerve fibers are of a single morphological type (type III). The cells that are presynaptic to nerve fibers within the taste buds of mice are morphologically diverse. A pattern of synaptic connectivity exists within murine taste buds such that a given nerve fiber receives synaptic input only from taste cells that are ultrastructurally similar. In the taste buds of both mice and rabbits, we have observed both divergence and convergence of synaptic input from the putative taste receptor cells onto nerve fibers, suggesting that at the level of the taste bud there is some integration of the information generated by individual receptor cells. In addition to typical chemical synapses, other cytoplasmic specializations (such as subsurface cisternae and atypical mitochondria) may be involved in interactions between taste bud cells and nerve fibers. © 1994 Wiley‐Liss, Inc.
Sulfated glycoprotein‐2 synthesized by nonciliated cells of the efferent ducts is targeted to the lysosomal compartment
Authors: Igdoura S. A. , Hermo L. , Morales C. R. 
Published: February 2005

AbstractThe epithelial nonciliated cells of the efferent ducts are specialized in internalizing many luminal substances. The nonciliated cells actively endocytose sulfated glycoprotein‐2 (SGP‐2), a major secretory protein of Sertoli cells and a homologue of human apolipoprotein J. This study was undertaken to investigate the internalization of Sertoli‐derived SGP‐2 and synthesis of an endogenous efferent duct form of SGP‐2 by nonciliated cells targeted to their secondary lysosomes on animals whose efferent ducts were ligated and/or received injections of tunicamycin. The regulation of synthesis of the endogenous form of SGP‐2 within nonciliated cells by hormones in general and testosterone in particular was also examined using hypophysectomized and castrated animals with or without subsequent testosterone replacement. Quantitative electron microscope immunocytochemistry was performed on groups of animals fixed with 4% paraformaldehyde and 0.5% glutaraldehyde in phosphate buffer for each experimental condition and their controls. In each case, the labeling density (number of gold particles/μm2) within the endosomal (endosomes) and lysosomal (dense multivesicular bodies and secondary lysosomes) compartments was calculated. The results revealed that ligation of the efferent ducts resulted in a significant decrease in the labeling density of the endosomal and lysosomal compartments. However, a baseline of about 18% of controls was still observed in the lysosomal compartment 24 h after ligation. In this compartment similar values were noted 24 h after tunicamycin treatment in conjaction with or without ligation. These results suggest that an endogenous form of SGP‐2 is synthesized by nonciliated cells and presumably targeted via small vesicles from the Golgi apparatus to the lysosomal compartment, but that the major portion of SGP‐2 within this compartment is derived via endocytosis of testicular SGP‐2. Hypophysectomy and castration also showed significant decreases in the labeling densities of these two compartments, but again a baseline level of labeling was noted in the lysosomal compartment. Subsequent testosterone administration to 7‐day hypophysectomized or castrated animals had no effect on the labeling density of the lysosomal compartment, as values comparable to the effect of hypophysectomy or castration alone were noted. Taken together these results suggest that the nonciliated cells of the efferent ducts synthesize an endogenous form of SGP‐2 that is targeted to the lysosomal compartment and which is not regulated by pituitary factors or testosterone. © 1994 Wiley‐Liss, Inc.
Crystal structure, chemical composition, and extended defects of the high‐Tc (Bi,Pb)2Sr2Can−1CunO4+2n+δ compounds
Authors: Eibl O. 
Published: February 2005

AbstractThis paper summarizes results obtained by high‐resolution transmission electron microscopy on the crystal structure and microstructure of the (Bi,Pb)2Sr2Can−1CunO4+2n+δ high‐Tc superconducting oxides. The experimental basis for the work presented here are high‐resolution structure images obtained at ultra‐thin (3 nm) areas of carefully prepared transmission electron microscope (TEM) samples. The analysis was carried out on a 400 kV TEM equipped with a pole piece yielding 0.17 nm point‐to‐point resolution. From the images obtained the projected crystal potential of the cations can be extracted directly, as confirmed by detailed image simulation. Structural analysis of the oxygen sublattice remains an unsolved problem by high‐resolution TEM (HRTEM), mainly because of the small scattering factors, and thus the contribution of the oxygen sublattice to the image contrast is small. The (Bi,Pb)2Sr2Can−1CunO4+2n+δ phases are modulated structures that can be understood as an average structure plus a superimposed displacement field. The crystal structure consists of BiO double layers and perovskite‐type cuboids (containing Sr, Ca, Cu, and O), which are sandwiched between the BiO double layers. The displacement field can be directly analyzed by HRTEM, and the largest displacement amplitudes of 70 pm were determined for the Bi atoms in the n = 1 compound. The chemical composition of the n = 2 and n = 3 compounds was determined by EDX in the TEM for the cation sublattice. A significant (Ca + Sr) deficiency (approximately 10%) with respect to Cu was found. The (Sr + Ca)/Cu mole fraction ratio was 1.31 for the Bi‐2212 phase and 1.14 for the Bi(Pb)‐2223 phase. The oxygen content cannot be determined by EDX in the TEM with the accuracy necessary for a correlation with electrical and superconducting properties. The defect structure present in these materials, that is, intergrown lamellae with different crystal structures and equal or different chemical compositions, stacking faults, and grain boundaries, is summarized. The importance of grain boundaries for understanding and improving superconducting properties is emphasized. © 1995 Wiley‐Liss, Inc.
Effects of hormones on the prostate in adult and aging men and animals
Authors: Sinowatz F. , Amselgruber W. , Plendl J. , Kölle S. , Neumüller Ch. , Boos G. 
Published: February 2005

AbstractLiterature on the effect of steroid hormones (androgens, estrogens, and other steroids), of peptide hormones (e.g., prolactin), and growth factors (e.g., EGF, FGF, TGF‐β), on the effect of castration and of experimental hormone application on the prostate is reviewed. Androgens have inductive, repressive, and interactive effects. They counterbalance an agonistic effect on proliferation and an antagonistic effect on cell death; they may influence DNA synthesis and induce the synthesis of substances with mitogenic effects on the prostate. Estrogens exert direct and indirect effects on the prostate. They suppress the secretion of gonatropins, thus repressing testicular androgen secretion. They stimulate the fibromuscular stroma and induce squamous metaplasia of the epithelium. Estrogens may also be involved in the onset of benign prostatic hyperplasia. Prolactin is preferentially bound in the diseased human prostate. An abundance of information has been gained on EGF, FGF, TGF‐β, and other growth factors. They may be involved in the development of prostatic hyperplasia. Castration leads to a striking reduction in prostatic size in a short period of time due to autophagic and heterophagic processes. In castrated individuals, the prostate is enriched in androgen‐independent cells. Experimental hormone application involves the substitution of androgens as well as anti‐androgens, long‐term application of different hormones, and application of combinations of drugs. The results of several studies are described. Further directions in the field of prostate research should concentrate on the role of growth factors in prostate development and pathology and on the effect of certain lectins on prostate diseases. We think that the investigation of interactions between steroid hormones and growth factors in normal and pathological neovascularization of the prostate is important. © 1995 Wiley‐Liss, Inc.