bluuebunny/crossref_metadata_2025_split huggingface dataset:
Functional magnetic resonance imaging of the human lumbar spinal cord
Authors: Moffitt Michael A. , Dale Brian M. , Duerk Jeffrey L. , Grill Warren M. 
Published: April 2005

AbstractPurposeTo determine whether consistent regions of activity could be observed in the lumbar spinal cord of single subjects with spin‐echo functional MRI (fMRI) if several repeated experiments were performed within a single imaging session.Materials and MethodsRepeated fMRI experiments of the human lumbar spinal cord were performed at 1.5 T with a single‐shot spin‐echo technique (half‐Fourier single‐shot turbo spin‐echo (HASTE)) as used by previous investigators, and a modified method (fluid‐attenuated inversion recovery (FLAIR)‐HASTE) that nulled the otherwise highly variable signal from the cerebrospinal fluid (CSF).ResultsFLAIR‐HASTE reduced the variability of the signal in the CSF region to background levels, and presumably reduced associated artifacts in the spinal cord. Consistent areas of activation in the spinal cord in response to a thermal stimulus just below the knee were not observed across the fMRI experiments with either method.ConclusionFLAIR‐HASTE was useful for removing artifact in the spinal cord signal induced by variability in the CSF signal. However, with the techniques used in this study, we were not able to confirm the presence of a consistent fMRI response in the lumbar spinal cord because of the signal enhancement by extravascular protons (SEEP) effect during thermal stimulation of the hindlimb. J. Magn. Reson. Imaging 2005;21:527–535. © 2005 Wiley‐Liss, Inc.
An improved method for spinal functional MRI with large volume coverage of the spinal cord
Authors: Stroman Patrick W. , Kornelsen Jennifer , Lawrence Jane 
Published: April 2005

AbstractPurposeTo develop a spinal functional MRI (fMRI) method with three‐dimensional coverage of a large extent of the spinal cord with minimal partial volume effectsMaterials and MethodsfMRI data of the cervical spinal cord were obtained at 1.5 T with a single‐shot fast spin‐echo imaging method, from thin contiguous sagittal slices spanning the cord. Thermal stimulation was applied to the palm of the hand in a block pattern with 15°C for stimulation and 32°C during baseline periods. Prior to analysis, the image data at each time point were reformatted into three‐dimensional volumes and resliced perfectly transverse to the spinal cord. Smoothing was applied only in the superior‐inferior (S/I) direction across uniform tissue types. Active voxels were then identified by means of a correlation to a model paradigm.ResultsThe resulting activity maps demonstrate activity primarily in ipsilateral sensory areas and in some motor areas, consistent with the spinal cord neuroanatomy. These data also demonstrate detail of the subsegmental organization of the spinal cord, as well as anatomical detail of the spinous processes and positions of nerve roots.ConclusionThe spinal fMRI method described enables large volume coverage of the spinal cord in three dimensions, with reliable and reproducible results. J. Magn. Reson. Imaging 2005;21:520–526. © 2005 Wiley‐Liss, Inc.
Subtraction of in‐phase and opposed‐phase images in dynamic MR mammography
Authors: Reichenbach Jürgen R. , Hopfe Jens , Rauscher Alexander , Wurdinger Susanne , Kaiser Werner A. 
Published: April 2005

AbstractPurposeTo develop and to evaluate an advanced image acquisition and analysis method for collecting T1‐weighted dynamic 3D MR mammography data sets by using a combined in‐phase (IP) and opposed‐phase (OP) imaging procedure.Materials and Methods3D MR mammography data sets were acquired by applying an interleaved gradient‐echo OP and IP imaging sequence during administration of contrast agent. A phantom data set, two volunteer breast data sets, and six patient breast data sets were recorded. Subtraction of dynamic in‐phase magnitude images was performed for clinical assessment. In addition, the magnitude subtraction (SIPOP) as well as the complex subtraction (cSIPOP) of the IP and OP magnitude and phase images were considered.ResultsThe detection of small lesions, lesion boundaries, and tumor offshoots in fatty tissue was improved by the subtraction of IP and OP images without the risk of signal cancellation due to partial volume effects.ConclusionDynamic MR mammography acquisition of IP and OP images in combination with appropriate data processing yields important supplementary information that can support routinely applied diagnostics of breast lesions that are fully embedded in fatty tissue by only marginally increasing acquisition time. J. Magn. Reson. Imaging 2005;21:565–575. © 2005 Wiley‐Liss, Inc.
Optimization of a blood pool contrast agent injection protocol for MR angiography
Authors: Robert Philippe , Violas Xavier , Santus Robin , Le Bihan Denis , Corot Claire 
Published: April 2005

AbstractPurposeTo design an ideal first‐pass profile for MR angiography (MRA) by optimizing a multiphasic injection protocol based on two experimental animal models.Materials and MethodsAn equivalent contrast‐enhanced (CE) MRA injection protocol was developed with controlled injection modalities (injection rate, volume, and dose) in rabbits and pigs. P792, a blood pool contrast agent, was injected in 17 male New Zealand rabbits and five farm pigs with variable injection schemes (mono‐ and multiphasic). From the gadolinium (Gd) blood concentration data, a simulation of an MR acquisition was performed to evaluate the impact of such an injection protocol on MR arterial signal and to select the best injection protocol.ResultsAn empirical relationship between the arterial peak concentration and the injection parameters was found in the rabbits and pigs, allowing precise prediction of the first‐pass profile. Of the four injection scheme strategies tested (standard bolus and bi‐, tri‐, and multiphasic injection protocols), the multiphasic “ramp” injection protocol provided the most optimal contrast agent pharmacokinetics with a durable plateau of concentration.ConclusionRamp injection protocol provides an optimized first‐pass profile for CE‐MRA. J. Magn. Reson. Imaging 2005;21:611–619. © 2005 Wiley‐Liss, Inc.
Human T‐cell lymphotropic virus antibody prevalence in HIV‐1‐infected individuals attending a sexual health clinic in South‐East London
Authors: Cooke Fiona J. , Geretti Anna Maria , Zuckerman Mark 
Published: April 2005

AbstractHuman immunodeficiency virus (HIV) and human T‐cell lymphotropic virus (HTLV) are both retroviruses with similar routes of transmission. A number of reports suggest variable clinical outcomes in HIV and HTLV co‐infected individuals. There is no published information regarding the prevalence of HIV and HTLV co‐infection in the UK. We therefore carried out an unlinked anonymised retrospective study to investigate the prevalence of HTLV co‐infection in HIV infected patients attending a sexual health clinic in South‐East London. We identified sera from 777 HIV‐1 positive adults (504 male, 273 female) who had attended our sexual health clinic between January 2000 and March 2001. Serum samples stored at −20°C were initially tested by HTLV‐1 and HTLV‐2 antibody enzyme‐linked immunoassay (EIA). An immunoblot assay was carried out on reactive samples to discriminate between viral subtypes. Samples with indeterminate results were also analyzed by Western blot. The prevalence of HTLV antibody was 0.8% (five patients with HTLV‐1 and one with HTLV‐2). Four of the HTLV‐1 co‐infected patients were females born abroad, of Black African or Caribbean origin. The other HTLV‐1‐infected patient was a male in the Black Other ethnic group born in the UK, demonstrating that transmission may occur outside recognized areas of high endemicity. The HTLV‐2 co‐infected individual was a White male born in Italy, and was likely to have been infected through intravenous drug use. The results suggest HTLV antibody screening should be considered in the local HIV infected population of south London. J. Med. Virol. 76:143–145, 2005. © 2005 Wiley‐Liss, Inc.
Distribution of genotype/subtype and mutational spectra of the surface gene of hepatitis B virus circulating in Hanoi, Vietnam
Authors: Thanh Thuy Le Thi , Ryo Haruko , Van Phung Le , Furitsu Katsumi , Nomura Taisei 
Published: April 2005

AbstractIn order to ascertain the molecular epidemiological features and mutational spectra of hepatitis B virus (HBV) in Hanoi, Vietnam, direct sequencing of the 219‐nucleotide fragment of the surface (S) gene of HBV from the sera of 40 patients mostly with chronic hepatitis were carried out. The samples were classified into genotypes by phylogenetic and genotype‐specific analysis, and subtypes by the deduced amino acid sequences. The results showed that genotype B with ayw1 was predominant genotype/subtype (63%), followed by genotype C with adr (18%). The quasi‐species nature of the HBV in the sera was observed in 24 of 40 samples examined. One sample (HN109) showed mixture of genotypes B and C. Among 26 amino acid substitutions, 16 were the variants and the remainders were mutations. In the “a” determinant region, three mutations with methionine to leucine (L) changes at the 133 amino acid residue were in the first loop and no mutations were in the second loop. A new mutation, threonine to methionine at 126 amino acid residue, was observed in one sample. In conclusion, the analysis of the S gene region of HBV showed that in Hanoi, genotype B with ayw1 was prevalent and the quasi‐species nature of HBV was also common. J. Med. Virol. 76:161–169, 2005. © 2005 Wiley‐Liss, Inc.
Molecular epidemiology of hepatitis B virus in Spain: Identification of viral genotypes and prediction of antigenic subtypes by limited sequencing
Authors: Echevarría José M. , Avellón Ana , Magnius Lars O. 
Published: April 2005

AbstractThe hepatitis B virus (HBV) genotypes were studied by a line probe assay (LiPA) and by direct sequencing of a 339 nucleotide fragment from the S region of the viral genome in samples from 269 carriers living in Spain, either native to Spain (231) or immigrants from Africa, Asia, and Eastern Europe (38). The sequences were also used to predict the HBV surface antigen (HBsAg) subtype on the basis of the amino acids specified at selected positions of the HBsAg molecule. Agreement between the two genotyping methods was found in most cases (98.1%) and a HBV genotype could be assigned to all samples. The viral groups D/ayw2 (30.1%), D/ayw3 (28.6%), and A/adw2 (21.2%) were prevalent, with an additional participation of the groups D/ayw4 (4.8%), F/adw4q− (1.9%), A/ayw1 (1.9%), and D/adw3 (0.7%), all of them present among the autochthonous carriers. Strains from genotypes B and C were found exclusively among Chinese immigrants. Genotype E strains were found in immigrants from Central Africa and in one patient native of Spain. Point mutations leading to amino acid changes of residues involved in the expression of the HBsAg subtype determinants were found in 12 samples (4.5%). Some mutations would predict the putative novel genotype‐subtype associations A/adw4q+, A/ayr, D/ayr, and E/ayw1, while others would suggest the loss of subtype‐specific determinants. The finding of HBV strains characteristic for Africa among the autochthonous carriers confirms the emergence of African HBV strains in Spain. J. Med. Virol. 76:176–184, 2005. © 2005 Wiley‐Liss, Inc.
Hepatitis C virus infection in cameroon: A cohort‐effect
Authors: Nerrienet Eric , Pouillot Régis , Lachenal Guillaume , Njouom Richard , Mfoupouendoun Jermie , Bilong Catherine , Mauclere Philippe , Pasquier Christophe , Ayouba Ahidjo 
Published: April 2005

AbstractA hepatitis C virus (HCV) serological study conducted in 2003 on 1,434 individuals in Yaounde and other HCV seroepidemiological studies on 2,066 sera sampled between 1993 and 1997 in four geographically distinct rural areas (Ntem, Mekas, Yokadouma, and Nditam) in Cameroon, are described. Two patterns of HCV seroprevalence were observed. The first pattern, represented by Nditam and Yokadouma populations, showed low HCV seroprevalence rates (2.9% and 3.3%, respectively) increasing moderately with age (9.0% and 16.7% after age 50). The second pattern showed high seroprevalence rates (6.9% for Yaounde, 14.4% and 16.7% for Ntem and Mekas, respectively). These rates increased dramatically with age (32.8%–49.5% after age 50). The age‐specific anti‐HCV prevalence curve of the 1993 Mekas survey paralleled those of the 1997 Ntem and 2003 Yaounde surveys. Using the year of birth as the x‐axis, the three curves closely matched each other. This clearly indicates a cohort effect for which the seroprevalence trends are clearly related with the year of birth, rather than the age. The highest prevalence was observed among people born around 1940. J. Med. Virol. 76:208–214, 2005. © 2005 Wiley‐Liss, Inc.
Detection of human herpesvirus 7 DNA in peripheral blood reflects mainly CD4+ cell count in patients infected with HIV
Authors: Boutolleau David , Bonduelle Olivia , Sabard Amélie , Devers Laure , Agut Henri , Gautheret‐Dejean Agnès 
Published: April 2005

AbstractThe opportunistic behavior and the potential interactions of human herpesvirus 7 (HHV‐7) with human immunodeficiency virus (HIV)‐1 in HIV‐1‐infected patients were investigated in comparison with HHV‐6, another human roseolovirus. Roseolovirus DNAs were detected and quantified in peripheral blood mononuclear cells (PBMCs) from 198 HIV‐seronegative healthy blood donors, 38 HIV‐1‐infected patients classified as long‐term non‐progressors, and 99 HIV‐1‐infected patients classified as progressors. The rate of HHV‐7 DNA detection was higher in healthy donors (78%) than in long‐term non‐progressors (47%; P = 0.0003) or in progressors (52%; P < 0.0001). HHV‐7 cell load was higher in healthy donors (median: 212 EqCop/106 PBMCs) and in long‐term non‐progressors (median: 105 EqCop/106 PBMCs) than in progressors (median: 48 EqCop/106 PBMCs; P < 0.0001 and P = 0.015, respectively). Among progressors, HHV‐7 detection was correlated positively with the CD4+ T‐lymphocyte count (P = 0.028). Neither HHV‐7 detection rate nor cell load was correlated with the HIV‐1 plasma load. As a whole, HHV‐6 detection rate and cell load were lower than the HHV‐7 counterparts, albeit exhibiting similar differences between healthy donors, long‐term non‐progressors, and progressors. In conclusion, HHV‐7 infection does not appear to be stimulated by HIV‐1 infection, nor interact with it. Rather, HHV‐7 detection rate and cell load reflect CD4+ T‐lymphocyte count, with higher values in healthy donors and long‐term non‐progressors than in progressors. J. Med. Virol. 76:223–228, 2005. © 2005 Wiley‐Liss, Inc.
HFRS causing hantaviruses do not induce apoptosis in confluent Vero E6 and A‐549 cells
Authors: Hardestam Jonas , Klingström Jonas , Mattsson Karin , Lundkvist Åke 
Published: April 2005

AbstractHantaviruses are known to cause little or no cytopathic effect in vitro, but have been suggested to cause apoptosis. To determine whether different hantaviruses would induce apoptosis to varying degrees, confluent Vero E6 cells were infected with the hemorrhagic fever with renal syndrome (HFRS) causing viruses Hantaan, Dobrava, Saaremaa, and Puumala. However, no difference was found in the percentage of adherent cells, or of cells with condensed nuclei, between non‐infected and virus‐infected cells at 3, 6, 9, or 12 days after infection. Furthermore, no differences in the percentage of cells with inter‐nucleosomal cleavage of DNA between uninfected and Hantaan infected cells could be detected using the TUNEL assay. Possibly, slightly more apoptotic cells, but never more than 5%, were detected after Hantaan infection of non‐confluent cells as compared to the negative control. Earlier reported results that Tula hantavirus induces significant apoptosis on Vero E6 cells were also verified, suggesting that non‐pathogenic hantaviruses might differ from HFRS‐causing strains regarding induction of apoptosis. In conclusion, the results indicated that the HFRS‐causing hantaviruses might induce a very low level of apoptosis in dividing cells, but not at all in confluent cells. J. Med. Virol. 76:234–240, 2005. © 2005 Wiley‐Liss, Inc.
Comparison of affinity chromatography and adsorption to vaccinia virus recombinant infected cells for depletion of antibodies directed against respiratory syncytial virus glycoproteins present in a human immunoglobulin preparation
Authors: Sastre Patricia , Melero José A. , García‐Barreno Blanca , Palomo Concepción 
Published: April 2005

AbstractAntibodies directed against human respiratory syncytial virus (HRSV) glycoproteins were depleted from a commercial immunoglobulin preparation (RespiGam) by two different methods. The first method consisted of repeated adsorption of RespiGam to Sepharose beads with covalently bound soluble forms of the two major viral glycoproteins (F or G). The second method consisted of adsorption of immunoglobulins to live cells expressing F or G glycoproteins on their surfaces after infection with vaccinia virus recombinants. While the first method removed efficiently antibodies that reacted with F and/or G glycoproteins by ELISA, it was inefficient in the elimination of anti‐HRSV neutralizing antibodies. In contrast, the second method removed efficiently anti‐HRSV antibodies that both reacted by ELISA and neutralized virus infectivity. These results confirm that human neutralizing antibodies are directed exclusively against HRSV F and G glycoproteins, and, they raise the possibility that F and G glycoproteins inserted into cell membranes differ antigenically from their soluble forms linked covalently to Sepharose beads. J. Med. Virol. 76:248–255, 2005. © 2005 Wiley‐Liss, Inc.
Preliminary study on the efficacy and safety of lamivudine and interferon α therapy in decreasing serum HBV DNA level in HBV positive transgenic mice during pregnancy
Authors: Li Duan , Xu De‐Zhong , Choi Bernard C.K. , Men Ke , Zhang Jing‐Xia , Lei Xiao‐Ying , Yan Yong‐Ping 
Published: April 2005

AbstractPrevious studies reported that the HBV DNA level in maternal serum is an important risk factor for intrauterine infection. Two antiviral drugs, lamivudine (3TC) and interferon α (IFNα), are used extensively clinically to reduce maternal HBV DNA level, However, because of a lack of evidence on the efficacy and safety of these drugs during pregnancy, they are categorized as grade C which prevents their use during pregnancy. This study provides new data on the efficacy and safety of lamivudine and IFNα in HBV positive transgenic pregnant mice. In this study, transgenic mice with high titers of hepatitis B virus (HBV) were employed to study the antiviral effects of 3TC and IFNα during different gestation periods. The study also examined changes in several serological HBV markers, the effects of perinatal exposure to antiviral drugs on the mother and offspring, drug efficacy in reducing the level of HBV DNA in maternal blood, and the safety to both the mother and offspring. The main conclusion of the study is that a significant decrease in HBV DNA level can be obtained after treatment with lamivudine but not with IFNα. No adverse effects were observed in the maternal mice and the offsprings. This finding may provide a rationale for the potential use of lamivudine for the treatment of pregnant women as a safe and effective measure to reduce the level of maternal viremia. J. Med. Virol. 76:203–207, 2005. © 2005 Wiley‐Liss, Inc.
Isotope‐edited UV Raman spectroscopy of protein–DNA interactions: binding modes of cyclic AMP receptor protein to a natural DNA recognition site
Authors: Toyama Akira , Matsubuchi Akiko , Fujimoto Naoko , Takeuchi Hideo 
Published: April 2005

AbstractIsotope‐edited UV Raman spectroscopy was applied to the study of the binding mode of cyclic AMP (cAMP) receptor protein (CRP) to a 22‐mer oligonucleotide (LacDNA) representing the primary CRP binding site of the E. coli lac promoter. LacDNA contains four guanine residues in the consensus pentamer regions (G5 and G7 on the sense strand and G5′ and G7′ on the anti‐sense strand) and they were individually labeled with deuterium at C(8) on the guanine ring. In the UV (251 nm) Raman difference spectrum between unlabeled and C(8)‐D‐labeled LacDNA, a sharp positive/negative peak pair appeared at ∼1490/1465 cm−1, which was assigned to a guanine ring vibration (ν6/ν6′) sensitive to the hydrogen bonding state at C(6)O. CRP is a dimeric protein and forms two complexes with the cofactor cAMP, i.e. half‐filled CRP–(cAMP)1 and fully liganded CRP–(cAMP)2. The ν6/ν6′ wavenumbers measured in the presence of CRP showed that CRP–(cAMP)1 binds to G5 and G5′ in a symmetric manner, whereas CRP–(cAMP)2 exhibits an additional binding to G7. Since the base sequence of LacDNA and the structure of CRP–(cAMP)1 are both asymmetric, the symmetric LacDNA–CRP–(cAMP)1 interaction suggests that CRP–(cAMP)1, which is considered to be dominant under physiological conditions, has a conformational flexibility to conform to structural asymmetry of natural DNA sequences. In contrast, the symmetric complex CRP–(cAMP)2 binds to LacDNA asymmetrically, suggesting a decreased flexibility of CRP in the fully liganded form. Isotope‐edited UV Raman spectroscopy provides unique information on the DNA recognition by CRP. Copyright © 2005 John Wiley & Sons, Ltd.
Hydrogen bonding dynamics and two‐dimensional vibrational spectroscopy: N‐methylacetamide in liquid methanol
Authors: Kwac Kijeong , Cho Minhaeng 
Published: April 2005

AbstractThe distribution of the fluctuating amide I mode frequency of N‐methylacetamide (NMA)–methanol solution at room temperature was recently found to be non‐Gaussian and can be decomposed into two Gaussians that are associated with two different solvation structures. In the present paper we discuss the temperature dependences of hydrogen bonding dynamics and their influences on one‐ and two‐dimensional vibrational spectra by carrying out molecular dynamics simulations of the same solution at five temperatures from 230 to 310 K. The radial distributions reveal the detailed solvent configuration around the NMA. The two‐species model where conformational transitions between the two distinct solvation structures are treated as a reversible reaction and the Onsager regression hypothesis was used to estimate the hydrogen bond association and dissociation rates and to study thermodynamic properties. By using the time evolution of the amide I mode frequency fluctuation, both IR absorption and two‐dimensional IR photon echo spectra were numerically simulated and compared with approximate two‐species model results. An approximation method that can be used to extract kinetic information of the hydrogen bonding dynamics from the spectra is briefly discussed. Copyright © 2005 John Wiley & Sons, Ltd.
Resonance Raman characterization of a high‐spin six‐coordinate iron(III) intermediate in metmyoglobin–azido complex formation trapped by microsecond freeze‐hyperquenching (MHQ)
Authors: Lu Shen , Wiertz Frank G. M. , de Vries Simon , Moënne‐Loccoz Pierre 
Published: April 2005

AbstractThe reaction of metmyoglobin with azide was used to characterize a novel freeze‐quench instrument with a mixing and freezing time resolution in the microsecond time range. Samples quenched within 95 and 245 µs after mixing of metmyoglobin with 1 M azide were characterized by low‐temperature UV–visible and resonance Raman spectroscopy with excitation into the Soret band. Comparison of these data with control samples where azide is absent or metmyoglobin is preincubated with azide demonstrates the formation of an intermediate complex in the first 95 µs after mixing that has fully decayed after 245 µs. Porphyrin skeletal modes displayed by this transient species identify it as a six‐coordinate high‐spin species. Minor low‐spin components are also observed and suggest that the hexacoordinated intermediate exists as a spin equilibrium. This preliminary study demonstrates the feasibility of this approach to detect new intermediates and to characterize early reaction intermediates in other metalloproteins. Copyright © 2005 John Wiley & Sons, Ltd.