bluuebunny/crossref_metadata_2025_split huggingface dataset:
In vivo magnetic resonance imaging of the human cervical spinal cord at 3 Tesla
Authors: Korzan Jeffrey R. , Gorassini Monica , Emery Derek , Taher Zaki A. , Beaulieu Christian 
Published: October 2002

AbstractPurposeTo demonstrate the feasibility of obtaining high‐quality magnetic resonance (MR) images of the human cervical spinal cord in vivo at a magnetic field strength of 3 T and to optimize the signal contrast between gray matter, white matter, and cerebrospinal fluid (CSF) on 2D gradient recalled echo (GRE) images of the cervical spinal cord.Materials and MethodsUsing a custom‐built, anatomically molded radio frequency (RF) surface coil, the repetition time and flip angle of a 2D GRE sequence were systematically varied in five volunteers to assess tissue contrast in the cervical spinal cord.ResultsThe 2D GRE parameters for an optimal balance between gray‐white matter and CSF‐white matter contrast at 3 T were determined to be a time‐to‐repetition (TR) of 2000 msec and a flip angle of 45°, with the constant short time‐to‐echo (TE) of 12 msec used in this study. Excellent tissue contrast and visualization of the internal anatomy of the spinal cord was demonstrated reproducibly in eight subjects using these optimal parameters.ConclusionThis study demonstrates that imaging the cervical spinal cord and delineating internal spinal cord structures such as gray and white matter is feasible at 3 T. J. Magn. Reson. Imaging 2002;16:21–27. © 2002 Wiley‐Liss, Inc.
Proton MRS in Kennedy disease: Absolute metabolite and macromolecular concentrations
Authors: Mader Irina , Karitzky Jochen , Klose Uwe , Seeger Uwe , Sperfeld Anne , Naegele Thomas , Schick Fritz , Ludolph Albert , Grodd Wolfgang 
Published: October 2002

AbstractPurposeTo investigate whether glutamine and glutamate (Glx) were elevated in Kennedy Disease (KD), and whether pathological proteins were spectroscopically visible as altered macromolecular (MM) resonances.Materials and MethodsTen patients with KD and twelve healthy volunteers were investigated using a stimulated echo acquisition mode (STEAM) spectroscopy sequence with metabolite‐nulling.ResultsThe concentrations of Glx remained unchanged in KD. An increased myo‐inositol (Ins), and elevated MM at 0.9 ppm were found within the motor area. The N‐acetyl‐aspartate (NAA)/creatine (Cr) ratio was negatively correlated to the number of cytosine adenosine guanine (CAG) repeats in the motor area.ConclusionThe elevated MM at 0.9 ppm may be attributed to a pathologically altered protein in KD. Additionally, the changes of Ins point to a clinically unexpected involvement of the motor cortex. The correlation of NAA/Cr with the number of CAG repeats indicates a link between metabolites and genetic failure. J. Magn. Reson. Imaging 2002;16:160–167. © 2002 Wiley‐Liss, Inc.
FAIR and dynamic susceptibility contrast‐enhanced perfusion imaging in healthy subjects and stroke patients
Authors: Hunsche Stefan , Sauner Dieter , Schreiber Wolfgang G. , Oelkers Peter , Stoeter Peter 
Published: October 2002

AbstractPurposeTo compare dynamic susceptibility contrast‐enhanced magnetic resonance imaging (DSC‐MRI) and the flow‐sensitive alternating inversion recovery (FAIR) technique for measuring brain perfusion.Materials and MethodsWe investigated 12 patients with acute stroke, and 10 healthy volunteers with FAIR and DSC maps of regional cerebral blood volume (rCBV), mean transit time (MTT), and regional cerebral blood flow (rCBF).ResultsIn volunteers good gray/white‐matter contrast was observed in FAIR, rCBF, and rCBV maps. Regions with high signal intensities in FAIR matched well with high values of rCBV and rCBF. In ischemic stroke patients a high correlation (r = 0.78) of the ipsi‐ to contralateral signal intensity ratios in FAIR and rCBF was observed in areas with perfusion abnormalities. In contrast, FAIR and rCBV (r = 0.50), and FAIR and MTT (r = −0.22) correlated only modestly. Furthermore, FAIR and rCBF demonstrated similar sizes of perfusion abnormality.ConclusionThis study demonstrates for the first time that FAIR and rCBF depict similar relations of perfusion in ischemic stroke patients and healthy subjects. J. Magn. Reson. Imaging 2002;16:137–146. © 2002 Wiley‐Liss, Inc.
Application of 1‐alkylamines to a liquid chromatographic/turbo ionspray tandem mass spectrometric method for quantifying metabolites of a new bone anabolic agent, TAK‐778, in human serum
Authors: Teshima Koichiro , Kondo Takahiro , Maeda Chie , Oda Tsuneo , Hagimoto Toshiaki , Tsukuda Ryoichi , Yoshimura Yoshinobu 
Published: October 2002

AbstractWe investigated the application of alkylamines, as additives to the mobile phase, to a quantification method for the metabolites, M‐III and M‐IV, of TAK‐778, which is a new bone anabolic agent, in human serum using liquid chromatography/tandem mass spectrometry (LC/MS/MS). Prior to setting up the analytical method, we found that 1‐alkylamines co‐existing with M‐III and M‐IV in the turbo ionsprayed solution formed 1‐alkylammonium adduct molecules of these metabolites during the ionization process, and the abundance of the adduct ions was considerably higher than that of protonated molecules ([M + H]+s) of these metabolites. Based on these findings, we investigated a variety of 1‐alkylamines and their spiked concentrations in the mobile phase for LC/MS/MS analysis to obtain higher sensitivities for the quantification of these metabolites. After these examinations, we found that 1‐hexylamine at a final concentration of 0.05 mmol l−1 was the most suitable additive for the mobile phase, and set the selected reaction monitoring (SRM) ions for the 1‐hexylammonium adduct molecule and [M + H]+, allowing about a fivefold gain in the SRM chromatographic peak compared with that without 1‐hexylamine. The adduct ion was considered to be formed by interaction between the amino group of 1‐hexylamine and the phosphoryl group of M‐III and M‐IV. The internal standard (I.S.) used was deuterated M‐III for each metabolite. The analytes and I.S. were extracted with diethyl ether from serum samples at neutral pH and injected into the LC/MS/MS system with a turbo ionspray interface. The limit of quantification for both analytes was 0.5 ng ml−1 when 0.1 ml of serum was used, and the calibration curves were linear in the range 0.5–100 ng ml−1. The method was precise; the intra‐ and inter‐day precisions of the method were not more than 5.6%. The accuracy of the method was good, with deviations between added and calculated concentrations of M‐III and M‐IV being typically within 16.6%. This method provided reliable pharmacokinetic data for M‐III and M‐IV after the intramuscular administration of TAK‐778 sustained‐release formulation in humans. Copyright © 2002 John Wiley & Sons, Ltd.
Hepatitis B vaccination: Risk‐benefit profile and the role of systematic reviews in the assessment of causality of adverse events following immunisation
Authors: Jefferson Tom , Traversa Giuseppe 
Published: October 2002

AbstractSince the early 1990s, several cases of demyelinating diseases were reported in France in association with the vaccination against hepatitis B. A large scientific, regulatory, and public debate took place to reassure the growing concern of the population. The objective of this paper is to examine the decision process undertaken both in France and in Italy; to outline the main findings of the studies conducted before and after the French decision to suspend the vaccination campaign among adolescents; and to describe the contribution of systematic review and causality criteria in the evaluation of the risk‐benefit profile of vaccines. Even on the basis of the early findings, which appeared to be compatible with a low increase in the risk associated with the vaccination, it was apparent that the risk‐benefit profile was unchanged for newborns, and was essentially unchanged for adolescents and for high‐risk adults. The availability of subsequent negative association studies provided further reassurance. It is essential to rely on well‐conducted systematic reviews to produce valid and reliable estimates of the risk‐benefit profile. J. Med. Virol. 67:451–453, 2002. © 2002 Wiley‐Liss, Inc.
Hepatitis B virus transmission in Brazilian hemodialysis units: Serological and molecular follow‐up
Authors: Teles Sheila A. , Martins Regina M.B. , Gomes Selma A. , Gaspar Ana M.C. , Araujo Natália M. , Souza Karla P. , Carneiro Megmar A.S. , Yoshida Clara F.T. 
Published: October 2002

AbstractA serological and molecular study of hepatitis B virus (HBV) infection was carried out in dialysis units in Central Brazil. Between 1995 and 1999, serum samples from all HBsAg‐positive hemodialysis patients (n = 43) were tested for HBeAg/anti‐HBe and subtyping by monoclonal ELISA. HBV DNA was detected by PCR and positive samples were genotyped by restriction fragment polymorphism pattern (RFLP) methodology. TheHBsAg prevalence declined in this population during the survey period (12–5.8%). HBeAg and anti‐HBe were detected in 23 (53.5%) and 18 (41.9%) sera, respectively. Thirty‐six samples could be HBsAg subtyped: 21 were subtype ayw3, 14 belonged to adw2 and one was identified as adw4. HBV DNA was present in 30 serum samples. Of these, 20 (66.7%) were genotype D, 9 (30%) genotype A, and 1 (3.3%) genotype F. In addition, the RFLP pattern could be determined in samples from 18/20 genotype D patients: D3 (10 strains), D7 (7 strains) and D4 (1 strain); from 8/9 genotype A patients: A1 (6 strains) and A3 (2 strains); and from the patient infected with genotype F: F1. Patterns D3 and D7 were associated closely with HBV infection in the two largest hemodialysis units studied. These findings confirm the value of the RFLP method as an effective molecular epidemiological tool for elucidating HBV transmission in hemodialysis units. J. Med. Virol. 68:41–49, 2002. © 2002 Wiley‐Liss, Inc.
Herpes simplex virus type 1 variants arising after selection with an antiviral carrageenan: Lack of correlation between drug susceptibility and syn phenotype
Authors: Carlucci M.J. , Scolaro L.A. , Damonte E.B. 
Published: October 2002

AbstractNatural carrageenans of diverse structural types isolated from the red seaweed Gigartina skottsbergii were recently identified as potent and selective inhibitors of herpes simplex virus types 1 and 2 (HSV‐1 and ‐2). The μ/ν‐carrageenan 1C3 was tested in vitro for its ability to select resistant variants. After serial passages of HSV‐1 strain F in Vero cells in the presence of increasing concentrations of 1C3, viruses emerged that were approximately 2‐ to 10‐fold more resistant to 1C3 inhibition than parental virus; these viruses formed large plaques with an altered syncytial phenotype (1C3‐syn). Plaque‐purified syncytial variants isolated from passages 13 and 14 have shown variable levels of resistance to 1C3, as well as to the other antiviral carrageenans isolated from G. skottsbergii and to other sulfated polysaccharides with known antiviral activity, such as heparin and dextran sulfate 8000, but all the clones were susceptible to acyclovir. The syn phenotype was not related to polysaccharide resistance. All the 1C3‐syn variants formed large syncytia in Vero and CV‐1 cells but did not induce fusion in other cell types. The growth efficiency in Vero cells, as well as the virulence for mice by intracerebral or intraperitoneal inoculation of 1C3‐syn variants, showed no significant alterations in comparison with the parental virus. The syncytial properties were not affected by cyclosporine or melittin, suggesting that an alteration on glycoprotein gB could be responsible for the syn phenotype induced by 1C3. J. Med. Virol. 68:92–98, 2002. © 2002 Wiley‐Liss, Inc.
Kaposi's sarcoma herpesvirus and HIV‐1 seroprevalences in prostitutes in Djibouti
Authors: Marcelin Anne‐Geneviève , Grandadam Marc , Flandre Philippe , Nicand Elisabeth , Milliancourt Catherine , Koeck Jean‐Louis , Philippon Michel , Teyssou Remy , Agut Henri , Dupin Nicolas , Calvez Vincent 
Published: October 2002

AbstractKaposi's sarcoma herpesvirus (KSHV) is linked causally to Kaposi's sarcoma. Epidemiological studies have shown that KSHV transmission can occur during sex among homosexual men, but heterosexual transmission seems to be very rare in KSHV low prevalence countries. A seroepidemiological study was conducted to determine whether KSHV is transmitted sexually between heterosexuals in an endemic country. Sera from 282 subjects of African origin living in Djibouti were tested for antibodies to KSHV and HIV‐1. Among the 282 individuals, 43 were female prostitutes working in the streets (group 1), 123 were female prostitutes working in luxury bars (group 2), 41 were non‐prostitute females (group 3), and 75 were non‐prostitute males (group 4). KSHV seroprevalence was 26, 20, 17, and 36% in groups 1, 2, 3, and 4, respectively. The seroprevalence of KSHV is not different between street or bar prostitutes and non‐prostitute females (OR = 1.67; P = 0.34 and OR = 1.18; P = 0.73). These results suggest that in this endemic country commercial sex work does not seem to be a risk factor for KSHV infection and provides evidence against heterosexual transmission of KSHV in the female population studied. J. Med. Virol. 68: 164–167, 2002. © 2002 Wiley‐Liss, Inc.
Inhibition of clinical isolates of human cytomegalovirus and varicella zoster virus by PNU‐183792, a 4‐oxo‐dihydroquinoline
Authors: Knechtel Mary L. , Huang Audris , Vaillancourt Valerie A. , Brideau Roger J. 
Published: October 2002

AbstractThe susceptibility of human cytomegalovirus (CMV) and varicella zoster virus (VZV) clinical isolates to PNU‐183792, a 4‐oxo‐dihydroquinoline, was examined. The antiviral potency of PNU‐183792, a non‐nucleoside inhibitor, was compared to the licensed nucleoside inhibitors ganciclovir and acyclovir using plaque reduction and virus yield reduction assays. PNU‐183792 was as potent against CMV as ganciclovir and was superior in potency to acyclovir against VZV. PNU‐183792 represents a new class of non‐nucleoside inhibitors of human herpesviruses. J. Med. Virol. 68: 234–236, 2002. © 2002 Wiley‐Liss, Inc.
Cellular glycosaminoglycans and low density lipoprotein receptor are involved in hepatitis C virus adsorption
Authors: Germi Raphaële , Crance Jean‐Marc , Garin Daniel , Guimet Josette , Lortat‐Jacob Hugues , Ruigrok Rob W.H. , Zarski Jean‐Pierre , Drouet Emmanuel 
Published: October 2002

AbstractThe initial binding of Hepatitis C virus (HCV) to the cell membrane is a critical determinant of pathogenesis. Two putative HCV receptors have been identified, CD81 and low‐density lipoprotein receptor (LDLr). CD81 interacts in vitro with the HCV E2 envelope glycoprotein, and LDLr interacts with HCV present in human plasma. In order to characterize these potential receptors for HCV, virus from plasma, able to replicate in cell culture, was inoculated on Vero cells or human hepatocarcinoma cells. HCV adsorption was assessed by quantitating cell‐associated viral RNA by a real‐time RT‐PCR method. Anti‐LDLr antibody, low and very low density lipoproteins inhibited significantly HCV adsorption, confirming the role of LDLr as HCV receptor. Only one out of the two anti‐CD81 antibodies used in this study led to a partial inhibition of HCV binding. This study also highlights a role for glycosaminoglycans (GAGs) in HCV adsorption: treatment of virus with heparin led to 70% inhibition of attachment, as did desulfation of cellular GAGs. Treatment of Vero cells with heparin‐lyase significantly inhibited virus attachment but by only 30%. These results demonstrate the complexity of the HCV binding step in which LDLr interacts strongly with HCV, whereas the interaction of HCV with GAGs and particularly with CD81 seem to be more moderate. J. Med. Virol. 68:206–215, 2002. © 2002 Wiley‐Liss, Inc.
Effects of gag mutations on human immunodeficiency virus type 1 particle assembly, processing, and cyclophilin a incorporation
Authors: Chiu Hsu‐Chen , Wang Fu‐Der , Yao Szu‐Yung , Wang Chin‐Tien 
Published: October 2002

AbstractA series of human immunodeficiency virus (HIV) mutants was constructed either by deletion or by linker insertion at various regions in the gag coding sequences. The ability of each mutant to assemble virus particles and to process them proteolytically, as well as incorporate cyclophilin A, was analyzed by Western immunoblot. This investigation indicated that most of the gag mutants were assembled and released at a level comparable to that of wild‐type virus. In an assay involving a single cycle of infection, mutants containing significant levels of cyclophilin A showed less in trans interference effects on wild‐type infectivity than did cyclophilin A‐deficient mutants. Mutations in the N‐terminal two‐thirds of capsid protein severely disrupted cyclophilin A incorporation, but they affected virus processing only slightly to moderately. Virions released from cyclosporine‐treated cells were processed, as well as virions made by the mock‐treated cells. Also, protease inhibitor treatment had no detectable effect on the cyclophilin A incorporation. These results indicate that cyclophilin A incorporation is not required for virus particle processing and that virus processing does not affect cyclophilin A incorporation. J. Med. Virol. 68: 156–163, 2002. © 2002 Wiley‐Liss, Inc.
Genotypic and phenotypic analysis of the env gene from South African HIV‐1 subtype B and C isolates
Authors: Treurnicht Florette K. , Smith Tracey‐Lee , Engelbrecht Susan , Claassen Matilda , Robson Brenda A. , Zeier Michelle , Rensburg Estrelita Janse van 
Published: October 2002

AbstractThe objective of the study was to assess the genotypic and phenotypic properties of 18 viral strains from human immunodeficiency virus‐1 (HIV‐1) positive patients and to identify subtype C isolates for vaccine design strategies. All the isolates were non–syncytium‐inducing (NSI) in both the primary and MT‐2 cell cultures. The amino acid charge of the V3 loop correlated with the NSI phenotype of the strains. The V3 competitive peptide enzyme immunoassay and DNA sequencing of the partial gp120 region gave concordant results on the 15 subtype C strains, whereas the three B genotypes gave a positive to B, a nonreactive to B, and a dual reaction to the B–D peptides, respectively. Sixteen of the isolates used only CCR5 as coreceptor whereas two isolates made use of additional coreceptors including CXCR4. In summary, all our subtype C isolates are NSI phenotypically and almost all of them use CCR5 exclusively as their coreceptor. J. Med. Virol. 68: 141–146, 2002. © 2002 Wiley‐Liss, Inc.
Wave speeds for a TLM model of moving media
Authors: O'Connor William J. 
Published: October 2002

AbstractIn a companion paper, a transmission line matrix (TLM) scheme was presented for the solution of the 1‐D equation of waves in moving media, ytt+αyxt+βyxx=0, describing the superposition of two waves with direction‐dependent speeds. The TLM model achieved controlled, direction‐dependent wave‐speed bias by means of supplementary link lines with notional ‘diodes’. Expressions for wave speed, presented without proof, were verified. Here a proof is presented using a new, time‐domain approach. The apparent (direction‐dependent) inductance and capacitance as seen by a single wave are first established in a generalized way from the TLM algorithm, from which two wave speeds and impedances are then derived. Copyright © 2002 John Wiley & Sons, Ltd.
Comparative analysis of Schwann cell lines as model systems for myelin gene transcription studies
Authors: Hai Mehreen , Muja Naser , DeVries George H. , Quarles Richard H. , Patel Pragna I. 
Published: October 2002

AbstractPrimary and immortalized cultured Schwann cells are commonly utilized in analyses of myelin gene promoters, but few lines are well‐characterized in terms of their endogenous expression of myelin genes. This is particularly significant in that cultured Schwann cells typically do not express myelin genes at levels comparable to those observed in vivo. In this study, the steady‐state levels of mRNA and protein for five Schwann cell markers (PMP22, P0, MBP, MAG, and LNGF‐R) were assessed in primary Schwann cells and six representative Schwann cell lines (RT4‐D6P2T, JS‐1, RSC96, R3, S16, and S16Y). RT4‐D6P2T and S16 cells were the most similar to myelinating Schwann cells based on their comparatively high expression of PMP22 and P0 mRNA. Both RT4‐D6P2T and S16 also expressed P0 protein. In addition, the previously reported P1‐A positive regulatory region from the myelination‐specific PMP22 promoter demonstrated significant activity in both these cell lines. However, nuclear proteins that interacted with P1‐A were different in extracts prepared from RT4‐D6P2T and S16 cells. Primary Schwann cells expressed myelin proteins at levels that were equal or less than those observed with the RT4‐D6P2T and S16 lines, indicating that primary Schwann cells are not necessarily better than immortalized Schwann cells as model systems for the study of myelin gene regulation. The data presented here demonstrate that cultured Schwann cells used to study myelin gene promoters have to be carefully selected on the basis of the endogenous level of expression of the myelin gene under study. © 2002 Wiley‐Liss, Inc.
So, how do people really use their handheld devices? An interactive study of wireless technology use
Authors: Schlosser Francine K. 
Published: October 2002

AbstractUsing a symbolic interactionist methodology, the diverse meanings assigned by employees to wireless handheld technology are investigated. Interviews were conducted with 11 individuals representing three organizations in the public and private sector enhancing our understanding of technology use within an organizational context. Wireless technology practices are examined as they relate to aspects of self‐identity, that is, the imaged self, the relational self, the integrated self and the isolated self. Individuals were able to fit the technology into their work and personal roles, and at the same time, adjusted these roles to fit new expectations arising from the technology. Innovative ways of using the technology were shaped by individual needs as users adapted their message contexts, social etiquette, self‐impressions, and ways of doing business. A need to self‐regulate emerged with high expectations of availability and the blurring of multiple work and personal roles. Copyright © 2002 John Wiley & Sons, Ltd.
The effects of quality improvement practices on team effectiveness: a mediational model
Authors: Lemieux‐Charles Louise , Murray Michael , Ross Baker G. , Barnsley Jan , Tasa Kevin , Ibrahim Salahadin A. 
Published: October 2002

AbstractResearchers have been challenged to specify the processes that quality improvement (QI) practices could be expected to generate and to explain how they might contribute to organizational effectiveness. This research article meets that challenge through a study of 97 teams in the health care field. The authors developed a ‘Quality Improvement Practices Index’ and showed that QI practices could be differentiated from traditional team‐level variables, and that such practices affect both directly and indirectly (through team‐level variables) team effectiveness. Two models were tested using structural equation modelling. It was found that the perceptions of the impact of QI practices on team effectiveness varied depending on who was assessing the team's performance—members of the team or managers who were external to the team but responsible for the team's performance. The authors discuss the implications of these results both for researchers and practitioners. Copyright © 2002 John Wiley & Sons, Ltd.