bluuebunny/crossref_metadata_2025_split huggingface dataset:
Phlorizin: a review
Authors: Ehrenkranz Joel R. L. , Lewis Norman G. , Ronald Kahn C. , Roth Jesse 
Published: December 2004

AbstractThe dihydrochalcone phlorizin is a natural product and dietary constituent found in a number of fruit trees. It has been used as a pharmaceutical and tool for physiology research for over 150 years. Phlorizin's principal pharmacological action is to produce renal glycosuria and block intestinal glucose absorption through inhibition of the sodium–glucose symporters located in the proximal renal tubule and mucosa of the small intestine.This review covers the role phlorizin has played in the history of diabetes mellitus and its use as an agent to understand fundamental concepts in renal physiology as well as summarizes the physiology of cellular glucose transport and the pathophysiology of renal glycosuria. It reviews the biology and pathobiology of glucose transporters and discusses the medical botany of phlorizin and the potential effects of plant flavonoids, such as phlorizin, on human metabolism. Lastly, it describes the clinical pharmacology and toxicology of phlorizin, including investigational uses of phlorizin and phlorizin analogs in the treatment of diabetes, obesity, and stress hyperglycemia. Copyright © 2004 John Wiley & Sons, Ltd.
Synthesis of ZnS Nanowires and Assemblies by Carbothermal Chemical Vapor Deposition and Their Photoluminescence
Authors: Zhang Hua , Zhang Shuyuan , Zuo Ming , Li Gongpu , Hou Jianguo 
Published: December 2004

AbstractA carbothermal method combined with CVD has been developed to synthesize ZnS nanowires and their self‐assemblies at low temperatures. In this process, active carbon serves as reductant to react with sulfur, which then goes on to form ZnS nanowires. X‐ray diffraction and X‐ray photoelectron spectroscopy studies indicate that the samples are single‐crystal wurtzite ZnS and are rich in sulfur. The nanowires have diameters ranging from 20 to 60 nm. High‐resolution electron microscopy shows the [100] growth direction for the mono‐dispersed nanowires and the different crystal orientation for the nanowires constituting the assembly. The photoluminescence (PL) peak is located at 490 nm. A vapor‐solid (VS) mechanism might explain the formation of ZnS nanowires. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Formation of Hexagonal Coordination Complexes (Eur. J. Inorg. Chem. 1/2005)
Authors: Schultheiss Nate , Ellsworth Joseph M. , Bosch Eric , Barnes Charles L. 
Published: December 2004

AbstractThe cover picture shows the hexagonal 2:4 coordination complex formed between 1,3‐bis(3′‐pyridylethynyl)benzene and copper(II) acetate. The ligand, synthesized by the Sonagashira coupling of 1,3‐ethynylbenzene with 3‐bromopyridine, was designed to form hexagonal coordination complexes with metals that favor linear coordination geometry. In this example the dimeric copper(II) acetate paddlewheel forms an almost linear connection between a pair of dipyridyl ligands. Details are discussed in the Short Communication by E. Bosch et al. on p. 45 ff.
Essential oil composition of Valeriana hardwickii var. arnottiana from the Himalayas
Authors: Sati S. , Mathela C. S. 
Published: December 2004

AbstractThe root oil of Valeriana hardwickii var. arnottiana (Valerianaceae) collected from the Milam region of the Himalayas was analysed by GC–MS. Twenty‐eight compounds were characterized, representing 92.1% of the total compounds detected. The essential oil showed a high content of oxygenated sesquiterpenes. The major constituents were valeracetate (17.3%), bornyl acetate (15.3%), methyl linoleate (11.7%), cuparene (10.4%) and α‐cedrene (6.2%). Valeracetate was conﬁrmed by 1H‐ and 13C‐NMR data; it may be used as a chemical marker for this variety. Copyright © 2004 John Wiley & Sons, Ltd.
The essential oil composition of Hypericum androsaemum L. leaves and ﬂowers from Iran
Authors: Morteza‐Semnani Katayoun , Saeedi Madjid 
Published: December 2004

AbstractThe composition of the essential oils obtained from the dried leaves and ﬂowers of Hypericum androsaemum L. (Hypericaceae) was analysed by GC and GC–MS. The major constituents of the essential oil of the leaves were caryophyllene oxide (35.8%), ishwarane (30.5%) and humulene epoxide II (5.6%). The major constituents of the essential oil of the ﬂowers were α‐guaiene (40.2%) and caryophyllene oxide (28.0%); 26 and 27 components were identiﬁed in the essential oils of the leaves and ﬂowers, respectively. Copyright © 2004 John Wiley & Sons, Ltd.
A semi‐implicit method conserving mass and potential vorticity for the shallow water equations on the sphere
Authors: Bonaventura Luca , Kornblueh Luis , Heinze Thomas , Ripodas Pilar 
Published: December 2004

AbstractA semi‐implicit discretization for the shallow water equations is discussed, which uses triangular Delaunay cells on the sphere as control volumes and conserves mass and potential vorticity. The geopotential gradient, the Coriolis force terms and the divergence of the velocity field are discretized implicitly, while an explicit time discretization is used for the non‐linear advection terms. The results obtained with a preliminary implementation on some idealized test cases are presented, showing that the main features of large scale atmospheric flows are well represented by the proposed method. Copyright © 2004 John Wiley & Sons, Ltd.
Numerical simulation of a micro–macro model of concentrated suspensions
Authors: Gati Y. 
Published: December 2004

AbstractWe deal here with the numerical simulation of a multiscale model of concentrated suspensions. We compare the deterministic solution procedure for the Fokker Planck equation with the Monte Carlo simulation of the stochastic differential equation. In particular, we examine questions of variance reduction. Copyright © 2004 John Wiley & Sons, Ltd.
Morphology and distribution of astrocytes in the molecular layer of the dentate gyrus in NZB/BLNJ, dreher, and C57BL/6J mice
Authors: Patrylo Peter R. , Nowakowski Richard S. 
Published: December 2004

AbstractNumerous ectopic granule cells are found in the molecular layer of the dentate gyrus in NZB/BINJ and dreher mutant mice. These ectopic neurons occur either singly or in small clusters. In contrast, few ectopic granule cells are seen in the dentate molecular layer of C57BL/6J mice and dreher control littermates. In this investigation we have examined the morphology, number, and distribution of molecular layer astrocytes in NZB/BINJ, dreher homozygotes, dreher littermate controls, and C57BL/6J mice to determine the effect of the presence of ectopic granule cells. In the molecular layer of C57BL/6J mice and dreher control littermates, astrocytes have a typical stellate appearance with processes emanating in all directions. The arborization of astrocytes in areas devoid of ectopic granule cells in NZB/BINJ mice and dreher homozygotes was similar to that in C57BL/6J mice and dreher control littermates. In contrast, the morphology of astrocytes in the immediate vicinity of ectopic granule cells or ectopic clusters was distinctly non‐stellate. Furthermore, the somata and processes of these astrocytes occasionally appeared to make intimate contact with the ectopic granule cells. A quantitative analysis of the number and distribution of astrocytes in NZB/BINJ vs C57BL/6J mice and dreher vs. control littermates indicated that these parameters were not altered by the presence of the ectopic neurons. We conclude that the trophic effects of ectopic neurons on glial cells can affect the growth and orientation of astrocytic processes without a concomitant effect on glial cell number. © 1994 Wiley‐Liss, Inc.
Vimentin immunoreactive glial cells in the fish optic nerve: Implications for regeneration
Authors: Cohen Ilana , Sivron Tomer , Lavie Vered , Blaugrund Eran , Schwartz Michal 
Published: December 2004

AbstractThe poor regenerative ability of neurons of the central nervous system in mammals, as compared with their counterpart in fish or amphibians, is thought to stem from differences in their immediate nonneuronal environment and its response to axonal injury. We describe one aspect of the environmental response to axonal injury in a spontaneously regonerating system‐the fish optic nerve. The aspect under investigation was the reaction of glial cells at the injury site. This was examined by the use of antibodies that specifically recognize vimentin in fish glial cells. In the present study, affinity‐purified vimentin antibodies were raised against a nonconserved N‐terminal 14‐amino acid peptide, which was predicted from the nucleotide sequence of vimentin. These antibodies were found to react specifically with glial cells in vitro. Moreover, the antivimentin antibodies stained both the optic nerve and the optic tract, but with different patterns. Specificity of the antibodies was verified by protein immunoblotting, tissue distribution, and labeling patterns. After injury, vimentin immunoreactivity initially disappeared from the site of the lesion due to cell death. Early signs of glial cell migration toward the injury site were evident a few days later. It is suggested that the reappearance of vimentin‐positive glial cells at the site of injury is associated with axonal elongation across it, and that they contribute to the regenerative ability of the fish optic nerve. © 1994 Wiley‐Liss, Inc.
Transplants of immature astrocytes promote axonal regeneration in the adult rat brain
Authors: Wunderlich G. , Stichel C. C. , Schroeder W. O. , Müller H. W. 
Published: December 2004

AbstractTo study beneficial effects of immature astrocytes on axonal regeneration in the injured adult mammalian brain, we have stereotactically implanted cultured astrocytes from embryonic (E 14–16) rat cerebral cortex into the lesion site following transection of the postcommissural fornix. The spatio‐temporal pattern of axonal degeneration and regrowth in the proximal fornix stump was investigated using wheat germ agglutinin‐horseradish peroxidase tracing techniques and quantitative analysis of myelinated axon profiles.Transection of the postcommissural fornix tract caused disintegration of the axons in the distal stump as well as rapid and pronounced retrograde axonal degeneration up to 800–1,200 μm proximal to the lesion site. While a small bundle of subicular fibers spontaneously extended to the lesion site within 4 weeks after injury, axonal regeneration was markedly stimulated in those animals that had received an astroglial implant. Following the former pathway, regenerating axons sprouted towards the implant but did not penetrate the graft. Instead, the axons elongated over the surface of the transplant, avoiding growth into the surrounding neuropil or into the distal fornix segment. In grafted animals we further observed a substantial increase in the number of myelinated axons of approximately 31.5% (at the level of 800 μm) and approximately 40% (at the 400 μm level) compared with the injured tract lacking a transplant. Our results indicate the capacity of juvenile astrocytes to stimulate axonal regeneration after injury of the post‐commissural fornix tract in the adult rat brain. We further demonstrate myelination of the regenerated axons. © 1994 Wiley‐Liss, Inc.
Restricted localization of L1 and N‐CAM at sites of contact between Schwann cells and neurites in culture
Authors: Martini Rudolf , Xin Yuanpei , Schachner Melitta 
Published: December 2004

AbstractSchwann cell‐axon contacts in developing and regenerating peripheral nerve in situ contain high levels of the recognition molecules L1 and N‐CAM, while the molecules are not detectable at the ab‐axonal cell surface of Schwann cells. To investigate whether Schwann cells, axons, or both contribute to the localization of the molecules at Schwann cell‐axon contacts, a heterologous cell culture system consisting of Schwann cells from mice and neurons from chicken was investigated by immunoelectron microscopy using species‐specific L1 and N‐CAM antibodies. We showed that Schwann cells expressed both molecules only at sites of contact between Schwann cells and neurites and other Schwann cells. Schwann cells not in contact with other cells expressed both molecules on their entire cell surface. In contrast, neurites expressed G4, an L1‐related molecule in chicken, on their entire cell surface independently of whether they were in contact with other cells or not. Thus, cultured Schwann cells localize L1 and N‐CAM selectively at cell contact sites and may thereby stabilize their attachment to the neighboring cellular partners. © 1994 Wiley‐Liss, Inc.
Extensive and long‐lasting changes of glial cells following transection of the poscommissural fornix in the adult rat
Authors: Stichel Christine C. , Muller Hans‐Werner 
Published: December 2004

AbstractInjury to the adult brain results in the formation of a glial scar that involves both activated astroglia and microglia/macrophages. Although reactive gliosis has been linked to failure of axonal regeneration in the adult mammalian CNS, the spatio‐temporal pattern of the postlesion responses in morphology and distribution of the major cellular constituents of the gliosis has attracted little attention. In an attempt to define these relationships, we have undertaken a systematic study of astrocytic and microglial/macrophagic responses after stereotactic transection of the postcommissural fornix in rat.To visualize astrocytes, microglia, and macrophages, antibodies against glial fibrillary acidic protein (GFAP), vimentin (VIM), complement receptor type 3 (OX42), and ED1 were used. The cellular responses occurring between 2 h and 1 year postlesion (PL) at various distances distal and proximal to the lesion site were studied.The timing and extension of the sequential glial reactions after postcommissural fornix transection are discussed in relation to the myelin degradation and spontaneous sprouting of injured axons that have previously been observed in this lesion model (Wunderlich et al: Glia 10:49–58, 1994). © 1994 Wiley‐Liss, Inc.
Microglial cells in the brain of Pleurodeles waltl (urodela, salamandridae) after wallerian degeneration in the primary visual system using Bandeiraea simplicifolia isolectin B4‐cytochemistry
Authors: Naujoks‐Manteuffel Christiane , Niemann Ulrike 
Published: December 2004

AbstractIn the brain of the salamander Pleurodeles waltl, microglial cells were investigated cytochemically with isolectin B4 (IB4) of Bandeiraea simplicifolia after optic nerve transection and during subsequent regeneration. Double‐labeling with an antibody directed against the glial fibrillary acidic protein of astrocytes revealed no immunoreactivity in microglial cells and confirmed the absence of non‐radial, free astroglial cells in the tectum. After two days, IB4‐labeled microglial cells began to populate the rostral parts of the primary visual system. The origin of these early vimentin‐immunoreactive microglial cells seemed to be mainly IB4‐labeled cells in a perivascular position and meningeal macrophages. After 12 days, microglial cells infiltrated the tectum in four layers: one in the ependyma, one in the outermost periventricular grey, and two in the degenerating visual neuropil where activated microglial cells displayed a ramified mor‐phology. After 3 weeks, microglial cells accumulated within the degenerating neuropil while reducing their processes. After 7 weeks, the number of microglial cells was still increased on the affected side. The subarachnoid space above the neuropil where regenerating retinal afferents arrived was filled with IB4‐labeled macrophages.Only very few microglial cells were seen in co‐existence with Müller cells in the lesioned and intact retinae, whereas microglial cells and macrophages were IB4‐labeled in the optic nerve head and at the ora serrata. © 1994 Wiley‐Liss, Inc.
Diazepam binding inhibitor fragment 33–50 (octadecaneuropeptide) immunoreactivity in the cerebellar cortex is restricted to glial cells
Authors: Vidnyánszky Zoltán , Görcs Tamás J. , Hámori József 
Published: December 2004

AbstractThe distribution of octadecaneuropeptide (ODN)‐like immunoreactivity (LI) and its relationship to γ‐aminobutyric acid (GABA)‐LI were investigated in the cerebellar cortex of adult rats with electron microscopy. At the electron microscopic level, ODN‐LI was found exclusively in glial cells. In addition to Bergmann glia and its processes, cerebellar astrocytes were also labelled, encapsulating unlabelled neuronal elements of the cerebellum. These ODN‐LI glial processes were observed in close apposition to synaptic junctions, but immunoreactivity could not be found in the synaptic cleft or in association with neuronal membranes. Since GABA‐LI is always associated with neuronal elements, the colocalization of GABA‐ and ODN‐LI could not be confirmed in the cerebellar cortex. Our results do not support the assumption that ODN is a neuron‐specific processing product of diazepam binding inhibitor. © 1994 Wiley‐Liss, Inc.
Expression and regulation of a glutamate receptor subunit by bFGF in oligodendrocyte progenitors
Authors: Gallo Vittorio , Wright Paul , McKinnon Randall D. 
Published: December 2004

AbstractOligodendrocyte progenitor cells (O‐2A) express both kainate‐preferring and AMPA‐preferring glutamate receptors (Gallo et al., Soc. Neurosci. Abstr., 18:653, 1992b; Gallo et al., 1994). The expression and regulation of the GluR‐4c, AMPA‐preferring subunit by growth factors was studied by Northern blot analysis of total RNA from purified rat cortical O‐2A progenitors. Differently from cortical neurons, O‐2A progenitors only expressed two high molecular weight GluR‐4c transcripts (6.2 and 4.2 kb), as observed also in cultured astrocytes. Basic fibroblast growth factor (bFGF) increased GluR‐4c transcript levels in O‐2A progenitors and its effects were not mimicked by platelet derived growth factor (PDGF) or fetal calf serum. Therefore, bFGF may regulate O‐2A progenitor responsiveness to glutamate during development through the expression of glutamate receptor subunits. © 1994 Wiley‐Liss, Inc.
Na+ channels of Müller (glial) cells isolated from retinae of various mammalian species including man
Authors: Chao T. Ivo , Skachkov Sergey N. , Eberhardt Wolfgang , Reichenbach Andreas 
Published: December 2004

AbstractWithin the last few years, the expression of voltage‐dependent, TTX‐sensitive Na+ channels has been demonstrated in several types of neuroglial cells such as astrocytes and Schwann cells. Recently, we reported the occurrence of such Na+ currents in retinal Müller (glial) cells from dog and cat. This paper deals with the description of the properties of Na+ currents in Müller cells isolated from retinae of several mammalian species, as well as from human retinae. These Na+ currents were eliminated by TTX (1μM), and by exposure to sodium‐free extracellular solution; typically, they were de‐monstrable only after blocking most of the K+ conductance by Ba2+ (1 mM). Voltage‐dependent activation and inactivation characteristics and time constants of the Na+ currents were similar to those of currents carried by neuronal Na+ channels. The esti‐mated number of sodium channels per cell was low (about 1,500 channels per 7,500μm2), and the K+ conductance exceeded the peak Na+ conductance by an average factor of 5. Thus, the cells were incapable of generating action‐potential‐like responses under cur‐rent clamp. Modelling estimations show that triggering of glial Na+ currents under physiological conditions, if any, can at best occur by ephaptic transmission at perinodal sites of optic axons. It is speculated that glial Na+ channels might be involved in neuro‐glial signalling events. © 1994 Wiley‐Liss, Inc.
Human angiotensinogen is highly expressed in astrocytes in human cortical grafts
Authors: Humpel Christian , Lippoldt Andrea , Ströumberg Ingrid , Bygdeman Marc , Wagner Jüurgen , Hilgenfeldt Ulrich , Ganten Detlev , Fuxe Kjell , Olson Lars 
Published: December 2004

AbstractHuman fetal parietal cortical tissue was transplanted to cortical cavities in immunosuppressed rats. Protoplasmic astrocytes in the human cortical grafts highly expressed human angiotensinogen mRNA as identified with 35S‐labeled and digoxigenin‐labeled riboprobes combined with immunohistochemistry for glial fibrillary acidic protein. Antibodies to human specific neurofilament protein 70 KD were used to characterize neurons in the graft and fiber outgrowth into the host brain. Immunohistochemistry revealed human angiotensinogen‐like immunoreactivity in many small protoplasmic astrocytes and very few large neurons. These results demonstrate that human angiotensinogen mRNA and protein is synthesized in immature human glia. We assume that angiotensinogen is transformed into angiotensin peptides, which may participate in the regulation of growth processes. The results suggest that human angiotensinogen may play a role during human ombryogenesis. © 1994 Wiley‐Liss, Inc.
Oligodendrocytes produce low molecular weight glycoproteins containing N‐acetyl‐D‐glucosamine in their Golgi apparatus
Authors: Supler Mitchell L. , Semple‐Rowland Susan L. , Streit Wolfgang J. 
Published: December 2004

AbstractLectin histochemistry using the Griffonia simplicifolia II lectin (GSL II) has revealed a novel group of glycoproteins containing terminal N‐acetyl‐D‐glucosamine (GlcNAc) residues in oligodendrocytes. The GlcNAc‐containing glycoproteins were not present in other types of glial cells, but were expressed by some neuronal cell populations. Within oligodendrocytes their localization was confined to the Golgi apparatus, as determined ultrastructurally. Biochemical analyses using tricine/SDS‐polyacrylamide gel electrophoresis and western blotting with GSL II showed the GlcNAc‐containing glycoproteins to be insoluble, with molecular masses ranging from 15 to 30 kDa. Our study provides a first account of insoluble, GlcNAc‐rich 15–30 kDa glycoproteins in oligodendroglia. The findings are discussed in the context of the functional significance of other known oligodendrocyte glycoproteins. © 1994 Wiley‐Liss, Inc.
Isolation and characterization of conditionally immortalized astrocyte cell lines derived from adult human spinal cord
Authors: Whittemore Scott R. , Neary Joseph T. , Kleitman Naomi , Sanon Henry R. , Benigno Adelaida , Donahue Roger P. , Norenberg Michael D. 
Published: December 2004

AbstractAs an approach to develop both oligodendrocytic and astrocytic cell lines from adult human spinal cord, a cellular preparation of highly enriched oligodendrocytes and their precursors was infected with a replication‐deficient retrovirus containing DNA sequences encoding the temperature‐sensitive mutant of SV40 large T antigen. Six immortal cell lines were obtained. At both permissive (33°C) and non‐permissive (38.5°C) temperatures, all cell lines were positive for vimentin, two demonstrated glial fibrillary acidic protein (GFAP) immunoreactivity, and none expressed oligodendrocyte or micro‐glial markers. The 2 GFAP‐positive cell lines [human spinal cord (HSC)2 and HSC6] were further characterized. Karyotype analysis revealed that both HSC2 and HSC6 cells showed gain of chromosomal material and structural chromosomal abnormalities. However, at non‐permissive temperature both cell lines were indistinguishable from primary human astrocytes by a number of criteria. These properties included glutamine synthetase activity, Na+‐dependent glutamate uptake, K+ flux, purine‐evoked Ca2+ mobilization and entry, and the ability to support neurite outgrowth from embryonic rat retinal explants. The HSC2 and HSC6 cell lines may prove to be valuable models for studying the physiological properties of adult human astrocytes. © 1994 Wiley‐Liss, Inc.