bluuebunny/crossref_metadata_2025_split huggingface dataset:
Differential gene expression in astrocytes from human normal and glaucomatous optic nerve head analyzed by cDNA microarray
Authors: Hernandez M. Rosario , Agapova Olga A. , Yang Ping , Salvador‐Silva Mercedes , Ricard Cynthia S. , Aoi Shun 
Published: August 2002

AbstractRecent advances in cDNA microarray technology have made it possible to analyze expression of several thousand genes at the same time. Using this technique, gene expression in human astrocytes cultured from glaucomatous and normal optic nerve heads (ONH) was compared. One hundred‐fifty genes were differentially expressed more than 5‐fold in glaucomatous cell cultures compared with normal. These genes are involved in a number of biological processes, including signal transduction, cell adhesion and proliferation, ECM synthesis, and degradation. Confirmation of differential gene expression was performed by quantitative RT‐PCR. Western blots and immunohistochemistry demonstrated gene products in cell cultures or in human ONH tissues. Proliferation, adhesion and migration assays tested physiological responses suggested by differential gene expression. Our study suggests that cultured glaucomatous ONH astrocytes retain in culture many phenotypic characteristics that may be relevant to their role in the pathogenesis of glaucoma and, in general to reactive astrocytes in the CNS. Potential applications of these data include the identification and characterization of signaling pathways involved in astrocyte function, studies of the role of steroid‐metabolizing enzymes in the glaucomatous ONH, and further exploration of the role of selected identified genes in experimental animal and in vitro models of glaucoma. GLIA 38:45–64, 2002. © 2002 Wiley‐Liss, Inc.
Characterization of a synaptiform transmission between a neuron and a glial cell in the leech central nervous system
Authors: Britz Frank C. , Lohr Christian , Schmidt Joachim , Deitmer Joachim W. 
Published: August 2002

AbstractThe cross‐talk between neurons and glial cells is receiving increased attention because of its potential role in information processing in nervous systems. Stimulation of a single identifiable neuron, the neurosecretory Leydig interneuron in segmental ganglia of the leech Hirudo medicinalis, which modulates specific behaviors in the leech, evokes membrane hyperpolarization directly in the giant glial cell (Schmidt and Deitmer. Eur J Neurosci 11:3125–3133, 1999). We have studied the neuron‐to‐glia signal transmission in the voltage‐clamped giant glial cell to determine whether this interaction exhibits properties of a chemical synapse. The glial response had a mean latency of 4.9 s and was dependent on the action potential frequency; the glial cell responded to as few as five Leydig neuron action potentials in 50% of the trials. The glial current was sustained for minutes during repetitive Leydig neuron activity without any sign of desensitization. The current was sensitive to tetraethylammonium, and its reversal potential of −78 mV shifted with the external K+ concentration. The glial response increased with the duration of the neuronal action potentials and was sensitive to the external Ca2+/Mg2+ concentration ratio. The results suggest that Leydig neuron activity leads to a Ca2+‐dependent release of transmitter from the neuronal dendrites, evoking an K+ outward current in the giant glial cell, implying a synapse‐like transmission between a neuron and a glial cell. GLIA 38:215–227, 2002. © 2002 Wiley‐Liss, Inc.
An immortalized jimpy oligodendrocyte cell line: Defects in cell cycle and cAMP pathway
Authors: Feutz Anne Catherine , Pham‐Dinh Danielle , Allinquant Bernadette , Miehe Monique , Ghandour M. Said 
Published: August 2002

AbstractNormal and jimpy oligodendrocytes in secondary cultures were transfected with plasmids containing the SV40 T‐antigen gene expressed under the control of the mouse metallothionein‐I promoter. Two immortalized stable cell lines, a normal (158N) and jimpy (158JP) cell line, expressed transcripts and proteins of oligodendrocyte markers, including proteolipid protein (PLP), myelin basic protein (MBP), and carbonic anhydrase II (CAII). Galactocerebroside and sulfatide were also detected with immunocytochemistry. Immunoelectron microscopy using gold particles showed that the truncated endogenous jimpy PLP was distributed throughout the cytoplasm and in association with the plasma membrane of cell bodies and processes. The length of the cell cycle in the jimpy oligodendrocytes in the absence of zinc was 31 h, about a 4‐h longer cell cycle than the normal line. In the presence of 100 μM zinc, the cell cycle became 3 h shorter for both cell lines, with the jimpy cell cycle duration remaining 4 h longer than the normal line. Interestingly, the jimpy cell line showed a significant deficiency in stimulation via the cAMP pathway. While the level of oligodendrocyte markers (PLP, MBP, and CAII) were significantly increased by dibutyryl cAMP (dbcAMP) treatment in the normal cell line, no changes were observed in the jimpy cell lines. This observation, together with previous results showing jimpy oligodendrocyte's failure to respond to basic fibroblast growth factor (bFGF), suggests a role for PLP in a signal transduction pathway. Jimpy and normal oligodendrocytes transfected with the SV40T antigen gene, driven by the wild‐type promoter of mouse metallothionein‐I, continue to express properties of oligodendrocytes and therefore provide a powerful model to explore the function of myelin proteins and to dissect the complexity of the jimpy phenotype. GLIA 34:241–252, 2001. © 2001 Wiley‐Liss, Inc.
SpL201: A conditionally immortalized Schwann cell precursor line that generates myelin
Authors: Lobsiger Christian S. , Smith Peter M. , Buchstaller Johanna , Schweitzer Beat , Franklin Robin J.M. , Suter Ueli , Taylor Verdon 
Published: August 2002

AbstractDramatic progress has been made over recent years toward the elucidation of the mechanisms regulating lineage determination and cell survival in the developing peripheral nervous system. However, our understanding of Schwann cell development is limited. This is partly due to the difficulties in culturing primary Schwann cell precursor cells, the earliest developmental stage of the Schwann cell lineage defined to date. Both the inability to maintain cultured Schwann cell precursor cells in an undifferentiated state and the technical difficulties involved in their isolation have hampered progress. We have conditionally immortalized rat Schwann cell precursor cells using a retrovirally encoded EGFR/neu fusion protein to circumvent these problems and to generate a source of homogeneous cells. The resulting SpL201 cell line expresses p75 and nestin, two proteins expressed by neural crest‐derived cells, as well as peripheral myelin protein 22, protein zero, and Oct‐6 as markers of the Schwann cell lineage. When cultured in EGF‐containing medium, the SpL201 cells proliferate and maintain an undifferentiated, Schwann cell precursor cell‐like state. The cell line is dependent on EGF for survival but can differentiate into early Schwann cell‐like cells in response to exogenous factors. Like primary rat Schwann cells, SpL201 cells upregulate Oct‐6 and myelin gene expression in response to forskolin treatment. Furthermore, the SpL201 cell line can form myelin in the presence of axons in vitro and is capable of extensively remyelinating a CNS white matter lesion in vivo. Thus, this cell line provides a valuable and unique tool to study the Schwann cell lineage, including differentiation from the Schwann cell precursor cell stage through to myelination. GLIA 36:31–47, 2001. © 2001 Wiley‐Liss, Inc.
Expression of 27 kDa heat shock protein (Hsp27) in immature rat brain after a cortical aspiration lesion
Authors: Sanz Olga , Acarin Laia , González Berta , Castellano Bernardo 
Published: August 2002

AbstractThe 27 kDa heat shock protein (Hsp27) is a well‐known member of the astroglial response to injury, playing a protective role against oxidative stress, apoptosis, and cytoskeletal destruction. Although several studies have been focused on the damaged adult brain, little is known about Hsp27 expression in the immature brain. In this work, we have examined the spatiotemporal pattern of Hsp27 expression in the normal postnatal rat brain following a cortical aspiration lesion at postnatal day 9. In the immature brain, Hsp27 is mainly observed in the internal capsule, although some scattered cells are also found in the ependyma, the corpus callosum, the septum, and hypothalamic glia limitans. In the internal capsule, Hsp27 expression is developmentally regulated, being significantly decreased from postnatal day 14. After a cortical aspiration lesion, de novo expression of Hsp27 is observed in cortical injured areas as well as in the secondary affected thalamus. In the cortex, expression of Hsp27 is first seen at day 1 postlesion (PL) surrounding the neurodegenerative area, becoming restricted to the glial scar at longer survival times. Although a pulse‐like expression of Hsp27 is observed in some microglial cells at day 1 PL, most Hsp27‐labeled cells are reactive astrocytes, which show GFAP overexpression and coexpress vimentin from day 3 PL. In the thalamus, astroglial Hsp27 expression is delayed, being first observed at day 5 PL. Thalamic Hsp27‐labeled astrocytes do not show vimentin expression. Our observations demonstrate astroglial expression of Hsp27 in areas of tissue damage following postnatal traumatic injury, suggesting an involvement of this cytoskeleton‐stabilizing protein in the remodeling processes following postnatal brain damage. GLIA 36:259–270, 2001. © 2001 Wiley‐Liss, Inc.
Olfactory receptor axons influence the development of glial potassium currents in the antennal lobe of the moth Manduca sexta
Authors: Lohr Christian , Oland Lynne A. , Tolbert Leslie P. 
Published: August 2002

AbstractIn the olfactory (antennal) lobe of the moth Manduca sexta, olfactory receptor axons strongly influence the distribution and morphology of glial cells. In the present study, we asked whether the development of the electrophysiological properties of the glial cells is influenced by the receptor axons. Whole‐cell currents were measured in antennal lobe glial cells in acute brain slices prepared from animals at different stages of metamorphic development (stages 3, 6, and 12). Outward currents were induced by depolarizing voltage steps from a holding potential of −70 mV. At all developmental stages investigated, the outward currents were partly blocked by bath application of the potassium channel blocker 4‐aminopyridine (4AP, 10 mM) or by including tetraethylammonium (TEA, 30 mM) in the pipette solution. The relative contribution of the 4AP‐sensitive current to the outward current increased from 18% at stages 3 and 6 to 42% at stage 12, while the TEA‐sensitive current increased from 18% at stage 3 to 81% at stage 6, and then declined again to 40% at stage 12. In contrast, in the absence of receptor axons, these changes in the contribution of the TEA‐ and 4AP‐sensitive currents to the total outward current did not occur; rather, the current profile remained in the most immature state (stage 3). The results suggest that olfactory receptor axons are essential for development of the mature pattern of glial potassium currents. GLIA 36:309–320, 2001. © 2001 Wiley‐Liss, Inc.
Depression in the community dwelling elderly: Do clinical and sociodemographic factors influence referral to psychiatry?
Authors: Eustace A. , Denihan A. , Bruce I. , Cunningham C. , Coakley D. , Lawlor B. A. 
Published: August 2002

AbstractBackgroundLittle is known about the reasons why depressed elderly patients are referred to the old age psychiatric services. Reasons for referral of depressed younger patients have been clarified however they may not be generalisable to an older population.ObjectivesThe purpose of this study is to examine which clinical and sociodemographic factors influence referral of patients with late life depression from primary care.MethodsTwenty‐eight people were identified with depression in a day hospital referred by their general practitioner. These were compared with fifty‐two people with depression in the community who had not been referred to the psychiatric services.ResultsHaving a more severe depression (p = 0.0016) and having co‐morbid anxiety (p = 0.0017) meant you were more likely to be referred to the day hospital. Gender did not appear to influence referral from general practitioners.ConclusionsIt appears that severity of depression and having higher levels of anxiety make it more likely that you will be referred by your general practitioner to the old age psychiatry services. Copyright © 2001 John Wiley & Sons, Ltd.
Estrogen replacement therapy is associated with less progression of subclinical structural brain disease in normal elderly women: a pilot study
Authors: Cook Ian A. , Morgan Melinda L. , Dunkin Jennifer J. , David Steven , Witte Elise , Lufkin Robert , Abrams Michelle , Rosenberg Susan , Leuchter Andrew F. 
Published: August 2002

AbstractBackgroundCortical atrophy, central atrophy, deep white‐matter hyperintensities, and periventricular hyperintensities are reported in normal aging.ObjectivesWe examined the effects of estrogen replacement therapy (ERT) on these forms of ‘subclinical structural brain disease’ (SSBD) in normal, postmenopausal women in a pilot, naturalistic, longitudinal study of 15 subjects.MethodsTwo assessments were performed at least two years apart, with volumetric magnetic resonance imaging (MRI) and neuropsychological testing.ResultsWomen receiving open‐label ERT showed significantly less progression of SSBD than those who did not.ConclusionsThe association between reduced SSBD progression and ERT suggests this intervention could help preserve normal brain structure in healthy elderly women. Copyright © 2002 John Wiley & Sons, Ltd.
Phosphorylation of 2‐(3‐methyl‐1,3‐diazabuten‐1‐yl)‐3‐ethoxycarbonylthiophenes with phosphorus(III) halides
Authors: Pinchuk Alexandr M. , Kovalyova Svetlana A. , Ivonin Sergey P. , Merkulov Anatoliy S. , Kudrya Tamara N. , Chaikovskaya Alexandra A. , Tolmachev Andrey A. 
Published: August 2002

Abstract2‐(3‐Methyl‐1,3‐diazabuten‐1‐yl)‐3‐ethoxycarbonylthiophenes are phosphorylated with phosphorus(III) halides in basic media at position 5 of the thiophene ring. Up to three heteroaromatic substituents can be introduced one by one at the same phosphorus atom. On this basis, mono‐, bis‐, and trishetaryl substituted P(III) and P(V) derivatives have been obtained. Phosphorylated 2‐(N,N‐dimethylformamidino)‐3‐ethoxycarbonylthiophenes provide a synthetic access to phosphorylated thienopyrimidines. © 2001 John Wiley & Sons, Inc. Heteroatom Chem 12:641–651, 2001
Thiofenchone s‐methylide and its spiro‐1,3,4‐thiadiazoline precursor
Authors: Huisgen Rolf , Mloston Grzegorz , Pröbstl Albert 
Published: August 2002

AbstractSpiro[fenchane‐2,2′‐(1,3,4)‐thiadiazoline] (6), prepared from thiofenchone and diazomethane, extrudes N2 (t1/2 22 min, 46°C, toluene) and furnishes the S‐methylide 7 which, in turn, closes the thiirane ring or else is intercepted by 1,3‐cycloadditions to dipolarophiles (tetracyanoethylene, maleic anhydride, N‐methyl‐1,2,4‐triazoline‐3,5‐dione, aromatic thioketones). When thiocarbonyl S‐methylide 7 is set free in methanol, fenchone S,O‐dimethylacetal is formed as an HX adduct. Catalysis by acetic acid converts 7 to 1‐(methylthio)‐α‐fenchene (25) by way of a Wagner‐Meerwein rearrangement. The addition of diazomethane to thiocampher leads, via thiadiazoline 12, to thiocamphor S‐methylide; the latter undergoes a 1,4‐H shift, thus affording 2‐methylthio‐2‐bornene (11). © 2001 John Wiley & Sons, Inc. Heteroatom Chem 12:136–145, 2001
The structures of diphenyl(diphenylsulfimido)(nitrido)sulfur(VI) and diphenyl(diphenyl‐sulfodiimido)(nitrido)sulfur(VI), Ph2(X)S=N–(Ph2)S≡N (X = lone pair, NH)
Authors: Fujii Takayoshi , Fujimori Teruyoshi , Miyoshi Shin , Murotani Satoru , Ohkubo Masanori , Yoshimura Toshiaki 
Published: August 2002

AbstractThe crystal structures of diphenyl(diphenylsulfimido)(nitrido)sulfur(VI) (Ph2S=N–(Ph2)S≡N) (1) and diphenyl(diphenylsulfodiimido)(nitrido)sulfur(VI) (Ph2(HN=)S=N–(Ph2)S≡N) (2) were determined by X‐ray crystallographic analysis. The former has a bent S–N–S unit with bridging S–N bond lengths of 1.651(1) and 1.622(1) Å and terminal S–N bond lengths of 1.467(1) Å; the latter compound possesses approximately a u‐shaped N–S–N–S–N unit with bridging S–N bond lengths of 1.653(2) and 1.576(2) Å, and terminal S–N bond lengths of 1.456(2) and 1.515(2) Å. Single‐point ab initio calculations were also carried out using the data from the crystal structures of 1 and 2. © 2001 John Wiley & Sons, Inc. Heteroatom Chem 12:263–268, 2001
Facile synthesis of a chiral auxiliary bearing the isocyanide group
Authors: Ilankumaran Palanichamy , Kisanga Philip , Verkade John G. 
Published: August 2002

AbstractThe synthesis of a chiral isocyanide possessing the easily cleaved menthoxy group is reported. © 2001 John Wiley & Sons, Inc. Heteroatom Chem 12:561–562, 2001
Reactions of 5‐methylene‐1,3‐thiazolidine‐2‐thione and 5‐methylene‐2‐oxazolidinone with isocyanates catalyzed by bases
Authors: Shi Min , Shen Yu‐Mei 
Published: August 2002

Abstract5‐Methylene‐1,3‐thiazolidine‐2‐thione and 5‐methylene‐2‐oxazolidinone can react with isocyanates to give the corresponding condensed urethanes in high yields in the presence of organic or inorganic bases under mild reaction conditions. © 2001 John Wiley & Sons, Inc. Heteroatom Chem 12:610–616, 2001
Bonding in the Si2H2 isomers: A topographical study
Authors: Chesnut D. B. 
Published: August 2002

AbstractChemical bonding in the isomers of the formally triply bonded Si2H2 system are studied from the point of view of electron localization function (ELF) bond basin populations and atoms‐inmolecules (AIM) delocalization indices. Calculation carried out at the B3LYP/6‐31 + G(d,p) and MP2 (FC)/6‐31 + G(d,p) level leads to ELF topographies and basin populations that are in good agreement with our intuitive chemical pictures of bonding in these molecules. One single, two double, and one triple siliconsilicon bonds are found in the four isomers. It is shown that, with one AIM exception, ratios of basin populations and delocalization indices are consistent and useful in characterizing the nature of the chemical bonding involved. © 2002 John Wiley & Sons, Inc. Heteroatom Chem 13:53–62, 2002; DOI 10.1002/hc.1106
Alternative approaches to obtain optimal bid values in contingent valuation studies and to model protest zeros. Estimating the determinants of individuals' willingness to pay for home care services in day case surgery
Authors: Dalmau‐Matarrodona Eulàlia 
Published: August 2002

AbstractThe use of day case surgery has increased rapidly as an alternative to inpatient surgery. Little is known, however, about the value of day case surgery to patients. The aim of this paper was to develop a contingent valuation survey to investigate how individuals value the costs of shifting from inpatient to day case surgery based on home care services. Using the willingness to pay (WTP) approach, two kinds of sequential experiments are compared: the maximum likelihood recursion (MLR) method and the C‐optimal sequential procedure. The goal of sequential experimentation is to find bid values that provide the maximum possible information about the parameters of the WTP distribution, especially when the sample size is small. The C‐optimal sequential procedure is shown to be an improvement, in terms of the statistical precision in small samples, over the MLR method. In addition, the paper presents a double hurdle (DH) approach for modelling the determinants of individuals' WTP. Using data from a contingent valuation survey conducted in 1996 on patients selected from the Day Case Surgery Unit in a hospital in the region of Catalonia, we argue that participation in the market offered and the level of consumption, that is, people's WTP, should be treated as individual choices. The results show that income and sex are related to WTP. Also, in this study, a clear presence of starting‐point bias, introduced by the bid offered, was found. It is concluded that the WTP technique is potentially useful in evaluating health care programmes, although it is important to note that the criteria used to find an optimal design (in our model to minimize the asymptotic variance of the estimator used) may be restrictive from an economic point of view. Copyright © 2001 John Wiley & Sons, Ltd.
The use of brush cytology and directed biopsies for the detection of nasopharyngeal carcinoma and precursor lesions
Authors: Chang Alexander R. , Liang Xiao‐Man , Chan Anthony T. C. , Chan May K. M. , Teo Peter M. L. , Johnson Philip J. 
Published: August 2002

AbstractBackgroundIt has been proposed that nasopharyngeal carcinoma (NPC) has an early noninvasive stage, designated nasopharyngeal intraepithelial neoplasia (NPIN). Hence, the detection and treatment of NPIN will prevent NPC from developing, and this would be similar to the strategies used for cervical cancer prevention. We wanted to ascertain the feasibility of using a brush sampler to collect cells for the cytologic diagnosis of NPIN and NPC. If successful, the technique could be used as a screening test in endemic areas.MethodsA disposable sampler (Uterobrush) was used to collect nasopharyngeal mucosal brushings from 546 patients for cytologic examination. After this, most patients had biopsies, and this allowed histologic‐cytologic correlation to be undertaken.ResultsIn 528 patients (96.7%) there were satisfactory cytologic and biopsy specimens for evaluation. There were 149 cases with positive histology and 103 had positive cytology (specificity was 100% and the sensitivity was 69.1%). One case of NPC with concurrent NPIN was seen among the biopsy specimens, but no case of NPIN was detected cytologically.ConclusionsThe cytologic pickup of NPC was substantially lower than that obtained on biopsy. More importantly, NPIN was uncommon. Therefore, a screening test that depends on the collection of cells for the microscopic diagnosis of NPIN and NPC is unlikely to have a major impact on the incidence of NPC. Furthermore, obtaining a good cytologic specimen from the nasopharynx is not simple, and this further limits this technique for mass screening purposes. The concept of a cytologic test for NPC, similar to the Pap test for the prevention of uterine cervix cancer, has still to be realized. © 2001 John Wiley & Sons, Inc. Head Neck 23: 637–645, 2001.