bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cautionary observations on preparing and interpreting brain images using molecular biology‐based staining techniques
Authors: Ito Kei , Okada Ryuichi , Tanaka Nobuaki K. , Awasaki Takeshi 
Published: September 2003

AbstractThough molecular biology‐based visualization techniques such as antibody staining, in situ hybridization, and induction of reporter gene expression have become routine procedures for analyzing the structures of the brain, precautions to prevent misinterpretation have not always been taken when preparing and interpreting images. For example, sigmoidal development of the chemical processes in staining might exaggerate the specificity of a label. Or, adjustment of exposure for bright fluorescent signals might result in overlooking weak signals. Furthermore, documentation of a staining pattern is affected easily by recognized organized features in the image while other parts interpreted as “disorganized” may be ignored or discounted. Also, a higher intensity of a label per cell can often be confused with a higher percentage of labeled cells among a population. The quality, and hence interpretability, of the three‐dimensional reconstruction with confocal microscopy can be affected by the attenuation of fluorescence during the scan, the refraction between the immersion and mounting media, and the choice of the reconstruction algorithm. Additionally, visualization of neurons with the induced expression of reporter genes can suffer because of the low specificity and low ubiquity of the expression drivers. The morphology and even the number of labeled cells can differ considerably depending on the reporters and antibodies used for detection. These aspects might affect the reliability of the experiments that involves induced expression of effector genes to perturb cellular functions. Examples of these potential pitfalls are discussed here using staining ofDrosophilabrain. Microsc. Res. Tech. 62:170–186, 2003. © 2003 Wiley‐Liss, Inc.
Cytomegalovirus glycoprotein B genotypes and central nervous system disease in AIDS patients
Authors: Vilas Boas Lucy S. , Ueda F. de Souza Vanda A. , Penalva de Oliveira Augusto C. , Rodriguez Viso Ana T. , Nascimento Filho Anderson M. , Nascimento Maria C. , Pannuti Cláudio S. 
Published: September 2003

AbstractTo investigate any association between cytomegalovirus glycoprotein B (CMV gB) subtypes and central nervous system (CNS) disease in AIDS patients, proportions of different gB genotypes detected in AIDS patients with CNS disease were compared with the gB genotypes detected in AIDS patients with no neurological disorder. The patients were matched by CD4+ cell counts. CMV was detected by PCR in cerebrospinal fluid (CSF) samples obtained from AIDS patients with CNS disease and from urine and saliva samples obtained from AIDS patients without CNS disease. CMV strains obtained were digested by restriction enzymes HinffI and RsaI to classify the genotypes. The CMV gB genotype was determined in 26 CSF samples. Of these, 11/26 (42.3%) typed as gB group 1, seven (26.9%) as gB2, four (15.4%) as gB3, and four (15.4%) as gB4. The CMV gB genotype frequency distribution in the 42 AIDS patients without CNS disease showed that 18/42 (42.8%) were classified as gB group 1, 10 (23.8%) as gB2, seven (16.6%) as gB3, and seven (16.6%) as gB4. In the present study, no association was found between CMV gB genotypes and CMV‐related central nervous system disease. J. Med. Virol. 71:404–407, 2003. © 2003 Wiley‐Liss, Inc.
Serological survey of hantavirus in Jardinopolis county, Brazil
Authors: Campos Gelse Mazzoni , de Sousa Ricardo Luiz Moro , Badra Soraya Jabur , Pane Clodoaldo , Gomes Uilho Antônio , Figueiredo Luiz Tadeu Morais 
Published: September 2003

AbstractHantaviruses are the causative agents of severe human diseases such as Cardiopulmonary Syndrome (CPS), described for the first time in 1993. Approximately 200 cases of this emergent disease were reported in Brazil until August 2002, with a 40% fatality rate. In May 2001, a hantavirus serologic survey was carried out among 15–70‐year‐old inhabitants of Jardinopolis County, State of São Paulo, Brazil. Blood samples of 818 inhabitants from urban and rural areas were collected by digitopuncture and IgG antibodies, detected by an indirect enzyme‐linked immunosorbent assay (ELISA) to the N recombinant protein of Andes hantavirus, were found in 14.3% of the samples, showing that this infection is common in Jardinopolis County, especially among adults irrespective of sex, profession, history of contact with rodents, or history of severe pneumonia. The results of the survey do not corroborate the idea that hantavirus infections are associated to rural activity and rodent contact, as observed with 20 Cardiopulmonary Syndrome cases occurred in the same region. Hantaviruses may be causing unrecognized infections, either asymptomatic or clinically nonspecific in addition to the syndrome. It may also be the case that more than one hantavirus type could be circulating in this region, causing mostly benign infections. J. Med. Virol. 71:417–422, 2003. © 2003 Wiley‐Liss, Inc.
Epitopes corresponding to the envelope genetic subtype are present on the surface of free virions of HIV‐1 group M primary isolates and can be detected in neutralization assays with extended incubation phases
Authors: Davis David , Donners Helen , Willems Betty , Vermoesen Tine , Heyndrickx Leo , Colebunders Robert , van der Groen Guido 
Published: September 2003

AbstractThe hypothesis is that there are neutralizing epitopes on the surface of free virions of human immunodeficiency virus type 1 (HIV‐1) that correspond to the genetic subtype of the envelope glycoprotein. Assays with extended incubation and reduced absorption phases are required to demonstrate neutralization with antibodies to these epitopes. These assays quantify virus infectivity, rather than reductions in release of antigen into culture supernatants. Neutralizing antibodies reduce virus infectivity by at least 80%, as scored by the presence/absence of antigen released after 14 days in culture of mitogen‐transformed peripheral blood mononuclear cells (PBMCs). The epitopes are shared within different subtypes of group M, but not group O, isolates. Individual plasma, selected from three, independent panels of seropositive individuals, cross‐neutralize within each subtype as well as the combinations of A with C, B with D or G, and C with CRF01_AE. Isolates within subtype B show the greatest variation in their resistance to neutralization, ranging from highly sensitive to highly resistant. No highly sensitive subtype D isolates were identified. Isolates from subtypes A, C, and CRF01_AE were all resistant. The strategic implication for vaccine design is that antibodies to a limited number of epitopes can neutralize more than 90% of the HIV‐1 isolates that are circulating currently in the world. Also, since only antibodies that produce an all‐or‐nothing loss in virus infectivity can reasonably be expected to prevent the viremic phase after in vivo infection, assays with extended incubation, and culture phases should be used to monitor current efficacy trials. J. Med. Virol. 71:332–342, 2003. © 2003 Wiley‐Liss, Inc.
HIV‐1 viral load determination based on reverse transcriptase activity recovered from human plasma
Authors: Malmsten Anders , Shao Xing‐Wu , Aperia Kajsa , Corrigan Gary E. , Sandström Eric , Källander Clas F.R. , Leitner Thomas , Gronowitz J. Simon 
Published: September 2003

AbstractWe describe a procedure (ExaVir™ Load) to carry out human immunodeficiency virus‐1 (HIV‐1) viral load testing using reverse transcriptase (RT) recovered from HIV‐1 virions in plasma. Samples from individuals infected with HIV‐1 were treated with a sulphydryl‐reactive agent to inactivate endogenous polymerases. Virions were then immobilised on a gel and washed in individual mini columns to remove RT‐inhibiting antibodies, antiviral drugs, and other RT inhibitors. Immobilised virions were lysed finally, and the viral RT eluted. The amount of RT recovered was quantified by a sensitive RT activity assay using either colorimetry or fluorimetry to detect DNA produced by RT. The “RT load” values of 390 samples from 302 HIV‐1 patients living in Sweden were compared to results obtained with an HIV‐1 RNA viral load assay. The correlation between the two tests wasr = 0.90,P < 0.0001. Four of 202 samples from healthy blood donors gave low positive values in the RT test. All samples in a panel with 10 HIV‐1 subtypes were positive by the RT load. The RT load test provides a technically less demanding and cost‐effective alternative to methods based on nucleic acid amplification. Being insensitive to genetic drift occurring in HIV, the assay should be of particular use in resource‐limited settings, where different subtypes and recombinant HIV strains occur. J. Med. Virol. 71:347–359, 2003. © 2003 Wiley‐Liss, Inc.
Increased susceptibility to HIV‐1 of peripheral blood lymphocytes in acute infection with Epstein‐Barr virus
Authors: Moriuchi Masako , Moriuchi Hiroyuki 
Published: September 2003

AbstractEpstein‐Barr virus (EBV) is an important pathogen in human immunodeficiency virus (HIV)‐infected individuals that causes lymphoma and other lymphoproliferative disorders upon disease progression; however, interaction between the two viruses during acute infection is not well known. Expression of CCR5, a major coreceptor for HIV, was enhanced on CD4+ T cells from patients with acute EBV infection. Furthermore, susceptibility of those cells to R5‐HIV‐1, but not X4‐HIV‐1, was increased. EBV effects on CCR5 expression on or susceptibility to R5‐HIV‐1 of CD4+ T cells did not require coinfection of the same cell with the two viruses, because CD4+ T cells from patients with acute EBV infection were not infected with EBV. Considering that both HIV and EBV are transmitted by intimate contact, such possible interaction between the two viruses may have implications for viral transmission and the pathogenesis of HIV disease. J. Med. Virol. 71:343–346, 2003. © 2003 Wiley‐Liss, Inc.
Early events of SARS coronavirus infection in vero cells
Authors: Ng M.L. , Tan S.H. , See E.E. , Ooi E.E. , Ling A.E. 
Published: September 2003

AbstractAn isolate from a patient in the recent severe acute respiratory syndrome (SARS) outbreak in Singapore was used to infect Vero E6 cells. This study concentrated on the first 30 min of infection. It was discovered that the SARS coronavirus attached, entered, and uncoated the nucleocapsids, all within a 30‐min period. At 5 min after infection, several virus particles lined the Vero cell plasma membrane. Virus particles were at various stages of fusion at the cell surface, since entry was not a synchronised process. After entry (10 and 15 min), spherical core particles moved into the cytoplasm within large vacuoles. Quite surprising at such early stages of infection (20 min), a virus‐induced change in the infected cells was evident. The induction of myelin‐like membrane whorls was obvious within the same vacuoles as the core particles. The significance of this virus‐induced change is unknown at this stage. By 25–30 min postinfection (p.i.), the spherical core particles appeared to be disassociating and, in their place, doughnut‐shaped electron‐dense structures were observed. These could be the virus genomes together with the helical nucleocapsids. They were no longer in large vacuoles but packaged into smaller vacuoles in the cytoplasm, and occasionally in small groups. J. Med. Virol. 71:323–331, 2003. © 2003 Wiley‐Liss, Inc.
Multicentric Castleman's disease treated with antivirals and immunosuppressants
Authors: Senanayake Sanjaya , Kelly John , Lloyd Andrew , Waliuzzaman Zubair , Goldstein David , Rawlinson William 
Published: September 2003

AbstractA patient negative for human immunodeficiency virus (HIV) developed multicentric Castleman's disease (MCD) and Kaposi's sarcoma (KS) associated with active human herpesvirus 8 (HHV‐8) infection. He was treated with sequential antiviral therapy, chemotherapy, and corticosteroids. HHV‐8 levels were monitored throughout the course of the patient's illness, and were found to rise on relapse. No consistent change in HHV‐8 levels was found with antiviral therapy. We demonstrate that in this patient antiviral therapy was clinically ineffective, and did not alter HHV‐8 levels, but that corticosteroid and combination chemotherapy led to clinical improvement. Despite the implication of HHV‐8 as a cause of MCD, few studies have correlated HHV‐8 levels with clinical response. J. Med. Virol. 71:399–403, 2003. © 2003 Wiley‐Liss, Inc.
Oxidative injury to endothelial cells due to Epstein‐Barr virus‐induced autoantibodies against manganese superoxide dismutase
Authors: Dalpke Alexander H. , Thomssen Reiner , Ritter Klaus 
Published: September 2003

AbstractDuring the course of acute Epstein‐Barr virus (EBV) infection, there is a rise of oxygen radical production. As a consequence, the production of the oxygen radical scavenger manganese superoxide dismutase (MnSOD) is increased. Patients with acute EBV infections regularly develop autoantibodies against MnSOD that are able to inhibit the enzyme activity in vitro. To elucidate the origin of the autoantibodies, the epitopes on MnSOD were determined. The entire sequence of MnSOD was synthesized as overlapping pentadecapeptides, which were scanned for their reactivity with sera of patients with acute EBV infections. Sera as well as affinity‐purified anti‐MnSOD antibodies reacted with the peptides pno15 (amino acids 47–61) and pno30 (amino acids 122–136) lying in crucial parts of the MnSOD tetramer. The two main epitopes pno15 and pno30 showed sequence homologies with EBV‐encoded proteins. Reactivity of affinity‐purified antibodies with a peptide of the homologous BGLF4 points to a molecular mimicry causing the occurrence of anti‐MnSOD antibodies. Anti‐MnSOD antibodies were able to block the protective effects of MnSOD in a model for oxidative damage produced by xanthine/xanthine oxidase in EAhy926 endothelial cells. Thus, these autoantibodies may contribute in vivo to the clinical symptoms by accumulation of toxic oxygen radicals. J. Med. Virol. 71:408–416, 2003. © 2003 Wiley‐Liss, Inc.
Evolution of hepatitis B virus sequence from a liver transplant recipient with rapid breakthrough despite hepatitis B immune globulin prophylaxis and lamivudine therapy
Authors: Kim Kyun‐Hwan , Lee Kwang‐Hee , Chang Hye‐Young , Ahn Sang Hoon , Tong Shuping , Yoon Young Joon , Seong Baik L. , Kim Soon Il , Han Kwang‐Hyub 
Published: September 2003

AbstractRecurrent hepatitis B virus (HBV) infection after liver transplantation can be prevented by prophylactic hepatitis B immune globulin (HBIG) and lamivudine therapy. However, reinfection may still occur due to the emergence of immune escape mutants and mutants of the YMDD motif. The full spectrum of mutations within the HBV genome during recurrent HBV infection remains to be documented. In this study, serial HBV isolates were characterized from a patient with lamivudine resistance prior to liver transplantation who developed recurrent HBV infection within 2 months of transplantation despite a high dose of HBIG and lamivudine therapy. Sequence analysis of full‐length viral genome before transplantation revealed many point mutations as compared with a wild‐type genotype C sequence, including the T1753G/A1762T/G1764A triple mutation in the basal core promoter and the G1896A nonsense mutation in the precore region. After transplantation and therapy, several point mutations in the HBV genome emerged or became dominant. These mutations caused L426I/L526M/M550I triple mutation (equivalent to L428I/L528M/M552I in previous reports) in the polymerase, and D144E mutation in the “a” determinant of HBsAg. Transfection experiments revealed that the D144E mutation reduced HBsAg affinity to anti‐HBs, confirming its active role for immune escape. Our study suggests that mutations in the HBsAg (D144E) and the polymerase (L426I/L526M/M550I) of HBV genome may be responsible for viral breakthrough despite HBIG prophylaxis and lamivudine therapy. J. Med. Virol. 71:367–375, 2003. © 2003 Wiley‐Liss, Inc.
Genomic and phylogenetic analysis of hepatitis C virus isolates: A survey of 535 strains circulating in southern France
Authors: Tamalet Catherine , Colson Philippe , Tissot‐Dupont Hervé , Henry Mireille , Tourres Christian , Tivoli Natacha , Botta Danielle , Ravaux Isabelle , Poizot‐Martin Isabelle , Yahi Nouara 
Published: September 2003

AbstractThe present study examines the distribution of Hepatitis C virus (HCV) genotypes in Marseille, France in 2001–2002 and evaluates the efficiency of two in house direct sequence PCR protocols based on 5′NC analysis or NS5B analysis. By 5′NC sequencing, the distribution of 535 HCV strains derived from patients attending gastroenterology and AIDS referral centers, or dialysis units was as follows: 33% were infected by genotype 1a; 26% by 1b; 7% by 2; 22% by 3a; 10.7% by 4. In univariate analysis, HCV distribution was associated with age and source of infection, whereas in multivariate analysis only injecting drug use was an independent determinant for genotype distribution. Among the 535 specimens submitted to 5′NC direct sequencing, 18% could not be classified accurately into subtypes. A subset of 187 samples was amplified efficiently and sequenced by targeting the NS5B region of the viral genome. The two methods yielded concordant results in 70% of cases. Specimens unsubtypeable or misclassified most frequently by 5′NC analysis were type 1b and subtypes 2a/2c and 4a/4c. The data show that 5′NC direct sequence analysis is a sensitive method to identify genotypes in all cases, but that it can lead to subtyping misclassification (in particular, subtype 1b and 1a) or doubtful results (in particular subtypes 2a/2c and 4a/4c). Conversely, NS5B direct sequence assay, based on phylogenetic analysis, allowed better discrimination between subtypes. These two approaches are complementary and should be made available in clinical laboratories to ensure a reliable survey of HCV strains. J. Med. Virol. 71:391–398, 2003. © 2003 Wiley‐Liss, Inc.
Mapping ganciclovir resistance in the human herpesvirus‐6 U69 protein kinase
Authors: Safronetz D. , Petric M. , Tellier R. , Parvez B. , Tipples G.A. 
Published: September 2003

AbstractHuman herpesvirus‐6 (HHV‐6) is a growing concern in immunocompromised individuals, such as in the transplant setting. Alone, or in concert with human cytomegalovirus (HCMV), infections with HHV‐6 are often severe enough to require antiviral therapy, generally in the form of ganciclovir (GCV). GCV resistance in HCMV is well documented, both clinically and in the laboratory, and has been shown to result from mutations in the UL97 protein kinase and/or UL54 DNA polymerase. GCV resistance in HHV‐6 has been documented. However, to date, it has only been investigated to a limited extent. The baculovirus system has previously been shown to be useful in studying GCV resistance with respect to herpesvirus protein kinase mutations. Using the baculovirus system, we created recombinant baculoviruses expressing either a wild‐type HHV‐6 U69 protein kinase or a mutated form containing homologous mutations to those documented in the UL97 protein kinase of GCV resistant HCMV isolates. The recombinant baculoviruses were used to infect Sf‐9 cells and cultured in the presence of GCV to determine the effect of the HHV‐6 U69 protein kinase mutations on GCV susceptibility. Mutations in the HHV‐6 U69 protein kinase, homologous to those in the HCMV UL97 protein kinase documented to cause GCV resistance, result in GCV resistance in the recombinant baculoviruses. J. Med. Virol. 71:434–439, 2003. © 2003 Wiley‐Liss, Inc.
Genetic variation in the VP7 gene of human rotavirus isolated in Montevideo‐Uruguay from 1996–1999
Authors: Berois Mabel , Libersou Sonia , Russi José , Arbiza Juan , Cohen Jean 
Published: September 2003

AbstractThe gene encoding the protein VP7 that induces the major neutralizing response has been sequenced from 34 human rotaviruses isolated from children with acute diarrhea in Montevideo (Uruguay) over a 4‐year period (1996–1999). These sequences were analyzed and compared to representative corresponding sequences available on databases. In most years, serotype G1 was present as the single serotype, except in 1999 when serotypes G1 and G4 were present simultaneously. Two G1 VP7 lineages were identified. Serotype G2 was present in 1997. The G4 isolates are grouped with Argentine strains and emerged during 1998 in a recently defined sublineage. Neither serotype G3 nor the emerging serotype G9 were isolated during the study. Antigenic domains of isolates and of representative reference strains of each serotype were compared. Sequences of strains isolated during the same year, showed a high degree of homology among strains belonging to the same serotype. J. Med. Virol. 71:456–462, 2003. © 2003 Wiley‐Liss, Inc.
Characterization by restriction fragment length polymorphism and plasmid profiling of Vibrio tapetis strains
Authors: Le Chevalier Patrick , Le Boulay Christine , Paillard Christine 
Published: September 2003

AbstractA total of nine Vibrio tapetis strains acquired from France, the United Kingdom and Norway were studied for their plasmid content. All the isolates contained from two to four large plasmids, ranging from approximately 60 to 100 kpb. in size. These plasmids were subsequently subjected to restriction fragment length polymorphism analysis (RFLP). Using the EcoRI enzyme, three different restriction patterns were demonstrated, two of which were closely related. On the basis of RFLP patterns, the strain from Norway differed noticeably from the French and British strains.
Airborne fungal spores at the Belgrad forest near the city of Istanbul (Turkey) in the year 2001 and their relation to allergic diseases
Authors: Çolakoǧlu Günay 
Published: September 2003

AbstractThe aim of this study was to investigate the relationship between airborne fungal spores and allergic diseases; for this reason, the airborne fungal spores that were obtained from five different locations of Belgrad Forest were isolated, determined and studied quantitatively.Totally 120 samples were examined by using the Petri Plate Gravitational Method, and fungi obtained from these samples were isolated and 600 colonies were counted. By identification of these isolations, 13 genera (Mucor, Rhizopus, Absidia, Aspergillus, Penicillium, Trichoderma, Trichothecium, Stemphylium, Cladosporium, Alternaria, Ulocladium, AureobasidiumandFusarium), 25 species and 10 different sterile fungi were determined. The identifications of these fungi were made according to their microscopic, macromorphological features and references.
Mutation analysis of the feedback inhibition site of phenylalanine‐sensitive 3‐deoxy‐D‐arabino‐heptulosonate 7‐phosphate synthase of Escherichia coli
Authors: Hu Changyun , Jiang Peihong , Xu Jianfeng , Wu Yongqing , Huang Weida 
Published: September 2003

AbstractIn Escherichia coli, the phenylalanine‐sensitive 3‐deoxy‐D‐arabino‐heptulosonate‐7‐phosphate synthase (DAHPS) AroG catalyzes the first committed step in the biosynthesis of aromatic compounds. To investigate the feedback inhibition site of AroG, mutated enzymes prepared with sequence‐overlap extension PCR were expressed and purified. The enzymatic activity assay showed that the amino acid replacements at Phe144, Leu175, Leu179, Phe209, Trp215Ala and Val221 completely or partially relieved feedback inhibition of AroG addressed by the phenylalanine. Ile10Ala and Δ(1–15) desensitized feedback inhibition and caused a 70 ∼ 90% loss of the specific catalytic activities. These results strongly suggest an involvement of the interior region and the N‐terminus of the polypeptide chain of AroG in the formation of the feedback inhibition site of DAHPS.