bluuebunny/crossref_metadata_2025_split huggingface dataset:
Three‐dimensional reconstructions of autonomic projections to the gastrointestinal tract
Authors: Powley Terry L. , Holst Mary‐Clare , Boyd David B. , Kelly Joshua B. 
Published: February 2005

AbstractThree‐dimensional reconstruction protocols in confocal microscopy are typically considered in terms of rendering separate stacks of optical sections. Single stacks, however, include volumes that are often too small to permit descriptions of entire neurons, complete axonal arbors, or complex neural networks. Furthermore, traditional tissue preparation protocols generally yield specimens too limited to permit reconstructions of complex neural systems. For 3‐D analyses of extensive networks such as the autonomic nervous system projections within the viscera, it is critical to incorporate appropriate tissue techniques, including suitable tracer protocols, into the reconstruction strategy. This report summarizes complementary technologies, including whole mount procedures, tracer techniques for identifying single fibers in situ, and methods of examining stacks of optical images, which make it practical to describe the complete terminal field of an individual axon in the gastrointestinal tract. Such methods establish that vagal motor axons travel long distances within their target organs, collateralize frequently, and ramify extensively. Vagal afferents have extensive, complex, and, in some cases, polytopic arbors within target tissues. © 1994 Wiley‐Liss, Inc.
Phorbol ester‐stimulated stellation in primary cultures of astrocytes from different brain regions
Authors: Davis‐Cox Margaret I. , Turner James N. , Szarowski Donald , Shain William 
Published: February 2005

AbstractStellation is the process by which astrocytes change from epithelial‐like to process‐bearing cells. Stellation occurs following activation of either cyclic AMP‐dependent protein kinase or protein kinase C. This process occurs through tubulin‐dependent rearrangement of the cytoskeleton. We have evaluated the ability of phorbol, 12‐myristate, 13‐acetate (PMA) to induce astrocyte stellation. Astrocytes from five brain regions (cerebellum, cerebral cortex, hippocampus, diencephalon, and brain‐stem) were examined to determine if all astrocytes would exhibit similar responses to this activator of protein kinase C. Stellation was evaluated following cell fixation by either phase optics using conventional light microscop, or scanning laser confocal light microscopy of cultures prepared using immunocytochemistry for tubulin and glial fibrillary acidic protein. Both the number of cells responding to PMA and the sensitivity to PMA varied for astrocytes from each brain region. PMA‐induced stellation was most robust in cerebellar and brainstem astrocytes, with greater than 70% responding. Less than 40% of hippocampal and diencephalic astrocytes responded to PMA at the maximum does (10−5 M). PMA also induced different numbers of processes or branching patterns of processes on astrocytes from different brain regions. The protein kinase C induced stellation response in astrocytes supports the hypothesis that astrocytes contribute to neural plasticity. © 1994 Wiley‐Liss, Inc.
Construction and analysis of a database representing a neural map
Authors: Troyer Todd W. , Levin Jacob E. , Jacobs Gwen A. 
Published: February 2005

AbstractWe describe the development and analysis of a quantitative database representing the global structural and functional organization of an entire sensory map. The database was derived from measurements of anatomical characteristics of a statistical sample of typical mechanosensory afferents in the cricket cercal sensory system. Anatomical characteristics of the neurons were measured quantitatively in three dimensions using a computer reconstruction system. The reconstructions of all neurons were aligned and scaled to a common standard set of dimensions, according to a highly reproducible set of intrinsic fiducial marks. The database therefore preserves accurate information about spatial relationships between the neurons within the ensemble.Algorithms were implemented to allow the integration of electrophysiological data about the stimulus/response characteristics of the reconstructed neurons into the database. The algorithms essentially map a physiological function onto a “field” representing the continuous distribution of synaptic terminals throughout the neural structure. Subsequent analysis allowed quantitative predictions of several important functional characteristics of the sensory map that emerge from its global organization. First, quantitative and testable predictions were made about ensemble response patterns within the map. The predicted patterns are presented as graphical images, similar to images that might be observed with activity‐dependent dyes in the real neural system. Second, the synaptic innervation patterns from the sensory afferent map onto the dendrites of a postsynaptic target interneuron were predicted by calculating the overlap between the interneuron's dendrites with the afferent map. By doing so, several aspects of the stimulus/response properties of the interneuron were accurately predicted. © 1994 Wiley‐Liss, Inc.
Morphological characteristics of boar efferent ductules and epididymal duct
Authors: Stoffel Michael H. , Friess Armin E. 
Published: February 2005

AbstractThe aim of the present study was to provide a comprehensive morphological analysis of the porcine epididymis in view of the specific functions being performed in different regions of this organ. Blood supply and microvasculature of efferent ductules and epididymal duct were investigated by means of corrosion casts which were analysed macroscopically and by scanning electron microscopy. This revealed blood supply to the testis and epididymis to be closely related. The capillary pattern was typical for the efferent ductules, the caput, corpus, and distal cauda epididymidis, respectively. Corrosion casts were also used to visualize the course of the efferent ductules themselves. Tissue samples from different regions of the efferent ductules and epididymal duct were examined by light microscopy and both scanning and transmission electron microscopy, with special attention being payed to transitional areas. Morphological criteria allowed the distinction of three segments within the efferent ductules and of the initial segment, proximal caput, distal caput, corpus, proximal cauda, and distal cauda regions of the epididymal duct. Components of the endocytic apparatus of efferent ductule principal cells were identified by ferritin uptake. Ultrastructural evidence of absorption in the epididymal duct was particularly prominent in proximal and distal caput. Extensive cisternae of rough endoplasmic reticulum and a well‐developed Golgi apparatus were indicative of active protein synthesis and secretion especially in the distal caput and corpus regions. However, assignment of various organelles in principal cells of the epididymal duct to either absorptive or secretory pathways still remains tentative. © 1994 Wiley‐Liss, Inc.
Order‐disorder in T, T′, and T* phase: Superconductors and related materials
Authors: González‐Calbet J. M. , Sayagués M. J. , Varela A. , Alonso J. M. , Caneiro A. , Vallet‐Regí M. 
Published: February 2005

AbstractAfter reviewing microstructural studies on superconducting materials showing T, T′, and T* structural types, results are presented on the microstructure of some n‐type superconductors and related materials prepared with accurate control of the oxygen stoichiometry. Electron microscopy is used to describe the ordering of interstitial oxygen defects in T‐type La2NiO4+δ leading to the formation of the n = 2 term of a homologous series with the general formula La8nNi4nO16n+1. Structural transitions and superstructure formation in the Pr2−x−yCexSryCuO4‐δ system are reported, where T, T′;, and T* phases are isolated as a function of both Ce and Sr content. © 1995 Wiley‐Liss, Inc.
Transmission EELS of oxide superconductors with a cold field emission TEM
Authors: Wang Y. Y. , Zhang H. , Dravid V. P. 
Published: February 2005

AbstractElectron energy loss spectrometry (EELS) with a cold field emission gun (cFEG) transmission electron microscope (TEM) is implemented to analyze the evolution of the electronic structure and dielectric function of oxide superconductors. The O‐K core loss spectra of p‐type doped oxide superconductors are analyzed in terms of holes formation on oxygen sites, while low loss spectra are analyzed for free carrier plasmas, other spectral excitations, and their crystallographic confinement.It is illustrated that the transmission EELS with a cFEG TEM very much complement soft X‐ray absorption spectroscopy and optical spectroscopy, with the added advantages of high spatial resolution (∼1–100 nm), and is compatible with other analytical, diffraction, and imaging techniques, which are readily available in a cFEG TEM. © 1995 Wiley‐Liss, Inc.
Mesenchymal‐epithelial interactions and transforming growth factor‐β1 expression during normal and abnormal prostatic growth
Authors: Timme Terry L. , Truong Luan D. , Slawin Kevin M. , Kadmon Dov , Park Sang Hee , Thompson Timothy C. 
Published: February 2005

AbstractMesenchymal‐epithelial interactions are associated with growth and morphogenesis of the prostate. We have detected three isoforms of transforming growth factor β (TGF‐β) in the developing mouse prostate that may mediate some of these interactions. Separation of the fetal urogenital sinus (UGS) tissue into mesenchymal and epithelial components indicated that mRNA expression of TGF‐β;1, 2, and 3 was more abundant in the mesenchyme compared to the epithelium. Immunohistochemical analysis revealed accumulation of TGF‐β1 in the mesenchyme surrounding ductules in the UGS and neonatal prostate. Further analysis of TGF‐β1 localization in surgically removed adult human prostate tissues revealed more intense staining associated with regions of abnormal growth compared to normally appearing tissue. The percent of the total stained area with extracellular accumulation of TGF‐β1 was 59% in prostate cancer, 26% in benign prostatic hyperplasia (BPH), and 8.6% in normal tissue. In additional immunohistochemical studies we observed that intracellular TGF‐β1 was predominantly associated with the epithelial cells in prostate cancer (epithelial cells = 33.5% of the total stained area, stromal cells = 13.3%, and unstained = 53.2%), whereas in BPH intracellular TGF‐β1 was predominantly associated with stromal cells (stromal cells = 32.2% of the total stained area, epithelial cells = 12.3%, and unstained = 55.5%). Although additional experimental and clinical studies are needed to better understand the relationships between TGF‐β1 and abnormal prostatic growth, our observations thus far suggest a role for TGF‐β1 in the development of benign and malignant growth abnormalities in the prostate. One approach to establishing the pathobiological significance of TGF‐β1 accumulation in the prostate is by introducing and overexpressing the TGF‐β1 cDNA in prostate tissue using the mouse prostate reconstitution model system. We discuss applicability of transgenic animal and organ reconstitution models for experimental studies concerning TGF‐β—induced prostate growth abnormalities. © 1995 Wiley‐Liss, Inc.
Patterns of myosin isoforms in mammalian skeletal muscle fibres
Authors: Hämäläinen Nina , Pette Dirk 
Published: February 2005

AbstractThe present article attempts to combine existing information on the distribution of fast and slow myosin isoforms in histochemically distinct muscle fibres. Four myosin heavy chain (MHC) isoforms, MHCI, MHCIIa, MHCIIb, and MHCIId(x), have been identified in small mammals and have been assigned to the histochemically defined fibre types I, IIA, IIB, and IID(x), respectively. These fibres express only one MHC isoform and are called pure fibre types. Hybrid fibres expressing two MHC isoforms are regarded as transitory between respective pure fibre types. The existence of pure and hybrid fibres even in normal muscles under steady state conditions creates a spectrum of fibre types. The multiplicity of fibre types is even greater when myosin light chains are taken into account. A large number of isomyosins results from the combinatorial patterns of various myosin light and heavy chains isoforms, further increasing the diversity of muscle fibres. As shown by comparative studies, the distribution of different fibre types varies in a muscle‐specific, as well as a species‐specific manner. © 1995 Wiley‐Liss, Inc.
Computer graphics of SEM images facilitate recognition of chromosome position in isolated human metaphase plates
Authors: Hodge L. D. , Barrett J. M. , Welter D. A. 
Published: February 2005

AbstractThere is general agreement that at the time of mitosis chromosomes occupy precise positions and that these positions likely affect subsequent nuclear function in interphase. However, before such ideas can be investigated in human cells, it is necessary to determine first the precise position of each chromosome with regard to its neighbors. It has occurred to us that stereo images, produced by scanning electron microscopy, of isolated metaphase plates could form the basis whereby these positions could be ascertained. In this paper we describe a computer graphic technique that permits us to keep track of individual chromosomes in a metaphase plate and to compare chromosome positions in different metaphas plates. Moreover, the computer graphics provide permanent, easily manipulated, rapid recall of stored chromosome profiles. These advantages are demonstrated by a comparison of the relative position of group A—specific and groups D—and G—specific chromosomes to the full complement of chromosomes in metaphase plates isolated from a nearly triploid human‐derived cell (HeLa S3) to a hypo‐diploid human fetal lung cell. © 1995 Wiley‐Liss, Inc.
Ultrastructural characterization of neurons recorded intracellularly in vivo and injected with lucifer yellow: Advantages of immunogold‐silver vs. immunoperoxidase labeling
Authors: Branchereau Pascal , Van Bockstaele Elisabeth J. , Chan June , Pickel Virginia M. 
Published: February 2005

AbstractImmunoperoxidase labeling of lucifer yellow provides a sensitive method for morphological characterization of neurons recorded intracellularly in vitro or in vivo. However, the reaction product is often so dense that it obscures ultrastructural details necessary for the analysis of synaptic contacts onto individually filled neurons. In the present study, we describe a silver intensification procedure using 1 nm gold labeling of lucifer yellow as an optimal means for immunocytochemically identifying single physiologically characterized neurons at the ultrastructural level. Single neurons in the frontal cortex of anesthetized rats were impaled in vivo and filled with lucifer yellow. The brians were then perfused with an acrolein fixative. Single vibratome sections through the recording site were reacted with a rabbit antibody directed against lucifer yellow followed by goat anti‐rabbit 1 nm gold‐labeled IgG and silver intensified. For comparison, additional sections were processed for immunoperoxidase detection of lucifer yellow. Labeled sections were processed for light microscopy or embedded in plastic for electron microscopy. The immunogold‐silver label as well as peroxidase reaction product of lucifer yellow was readily detected in cell bodies, proximal and distal dendrites, and spines. However, in contrast to immunoperoxidase, the immunogold‐silver reaction did not obscure subcellular orgnelles. Most importantly, the synaptic junctions formed by afferents to the filled neuron were more easily identifiable following the immunogold‐silver procedure. This clear visualization of postsynaptic densities is essential for examining synaptic circuitry between afferents and physiologically characterized neurons. © 1995 Wiley‐Liss, Inc.
Dystrophin expression in the developing conduction system of the human heart
Authors: Ginjaar Ieke B. , Virágh Szabolcs , Markman Marry W. M. , Van Ommen Gert‐Jan B. , Moorman Antoon F. M. 
Published: February 2005

AbstractDuchenne muscular dystrophy (DMD) is frequently associated with myocardial involvement. Dystrophin, the DMD protein, is found at the plasmamembrane of striated muscle fibers. Although dystrophin is missing in most or all muscle fibers of DMD patients, cardiac muscle is not as severely affected as skeletal muscle. Therefore it is of great importance to study the expression of dystrophin in normal cardiac muscle. We performed immunohistochemical studies and examined cardiac muscle of fetuses of 8 to 13 weeks of development on dystrophin expression. At these stages dystrophin is observed in the myocytes of the developing ventricular conduction system and in the atrial cardiomyocytes. Dystrophin was absent from the heart of a 12‐week‐old DMD fetus. © 1995 Wiley‐Liss, Inc.
Mapping of the orientation of myocardial cells by means of polarized light and confocal scanning laser microscopy
Authors: Jouk Pierre‐Simon , Usson Yves , Michalowicz Gabrielle , Parazza Franck 
Published: February 2005

AbstractThe study of the topological organisation of myocardial cells is a basic requirement for the understanding of the mechanical design of the normal and pathological heart. We developed a technique based on multiparametric image analysis of transmitted polarized light to generate maps of the azimuth and the elevation angles of the myocardial cells. The properties of birefringence of the myocardium embedded in methylmetacrylate were measured in papillary muscles with monitored 3D orientation. This birefringence is positive uniaxial with a 0° extinction angle when the axis of the fiber is parallel to the axis of the polarizer or the analyzer. Thick sections were studied between crossed polars, and four images of each section were digitized for an angle of the polarizer with the section varying from 0–67.5° in steps of 22.5°. The amounts of transmitted light for each setup of the polarizer were combined in order to extract the values of the azimuth angle (modulo 90°) and the elevation angle of the myocardial cells, according to the Johannsen equation. The respective maps of these angles were calculated and then assessed with confocal scanning laser microscopy. This method provides an efficient and accurate tool for the study of the histological architecture of the fetal and neonatal heart. © 1995 Wiley‐Liss, Inc.
Section directed cryosectioning of specimens for scanning electron microscopy: A new method to study cardiac development
Authors: Seo Jeong‐Wook , Kim Eul‐Kyeong , Brown Nigel A. , Wessels Andy 
Published: February 2005

AbstractA new method to study the developing heart was developed. Using this “section directed” cryosectioning method, appropriate fixed embryos can be trimmed optimally to obtain sectional planes that, if necessary, can be matched with histologically treated sections. As a result, the morphological information obtained with the scanning electron microscope can be compared in detail with the information on the molecular phenotypes of the subpopulations of cells as deducted from staining patterns of the sections. This method allows combination of the specific advantages of sophisticated histological techniques, such as immunohistochemistry and in situ hybridisation, with those of the scanning electron microscope. © 1995 Wiley‐Liss, Inc.
Design and implementation of a database and program for 3D reconstruction from serial sections: A data‐driven approach
Authors: Verbeek Fons J. , Huijsmans D. P. , Baeten R. J. A. M. , Schoutsen N. J. C. , Lamers W. H. 
Published: February 2005

AbstractThis paper describes a structured approach for a standard setup of a computer program for 3D reconstruction from serial sections. Three‐dimensional reconstruction as a technique increases in importance as, along with modern immunohistochemical techniques, it is a tool in the understanding of three‐dimensional development patterns. In order to apply 3D reconstruction technique in a standard laboratory setup, an attempt was made to streamline the input and the manipulation of the data such that results are obtained easily. One will find a combination of two approaches in this paper: the first is a strict ordering of the complex data, and the second is an ordering of the processes that one wishes to apply on the data (together, these two approaches constitute an information analysis); because it was observed that developmental biologists tend to work from simple lines to describe their observations, the contour model was chosen as the vehicle to build a reconstruction model from. Consequently, the data is ordered in a database that has to be manipulated to get the data out in the desired format. The most important output format is a display of the reconstructed contour stack on a graphical computer screen. Together with the other data manipulation processes, such as the input, the inspection, the revision (correction), and the reconstruction, all processes are described using the reconstruction of an 11 embryonic days (ED) rat embryo as an example. Finally, the merits of the program are illustrated with an example from the development of the human embryonic heart. © 1995 Wiley‐Liss, Inc.
Three‐dimensional analysis and visualization of myofibrillogenesis in adult cardiomyocytes by confocal microscopy
Authors: Messerli J. M. , Perriard J.‐C. 
Published: February 2005

AbstractConfocal light microscopy has found its place among the standard analytical tools in cell and molecular biology. When combined with techniques such as immunofluorescence or fluorescent in situ hybridization, the spatial distribution of individual biological components can be traced within cells and tissues and, under certain circumstances, even with living samples. In this article, advanced 3D visualization techniques have been applied to analyze the distribution of myofibrillar proteins in cultured adult rat cardiomyocytes. By combining confocal immunofluorescence microscopy with specially designed three‐dimensional visualization, we have obtained images which are similar to those obtained with the scanning electron microscope. The subcellular distribution of proteins expressed after transfection of cDNA is monitored in the cultured heart cells. The expressed proteins are distinguished from their endogenous counterparts by the use of an epitope tagging technique. The described methods are suitable to specifically monitor the behavior of several closely related isoprotein mutants in cell or tissue preparations. © 1995 Wiley‐Liss, Inc.