bluuebunny/crossref_metadata_2025_split huggingface dataset:
Some more 5‐GDDs and optimal (v), 5, 1)‐packings
Authors: Ge Gennian , Ling Alan C. H. 
Published: January 2004

AbstractIn this paper, we continue to investigate the existence of 5‐GDDs with types g5 m1 and gu. As an application, the known results on the existence of optimal packings with block size 5 are also improved. © 2003 Wiley Periodicals, Inc.
3‐Designs of PSL(2, 2n) With block sizes 4 and 5
Authors: Keranen M. S. , Kreher D. L. 
Published: January 2004

AbstractWe determine the distribution of 3‐designs among the orbits of 4‐ and 5‐element subsets under the action of PSL(2,2n) on the projective line. Thus we give complete information on all Kramer–Mesner matrices for the action of PSL(2,2n) on 3‐sets versus 4‐ and 5‐sets. As a consequence, all 3‐designs with block sizes 4 and 5 and automorphism group PSL(2,2n) can immediately be obtained. © 2003 Wiley Periodicals, Inc.
Hamilton cycle rich two‐factorizations of complete graphs
Authors: Bryant Darryn 
Published: January 2004

AbstractFor all integers n ≥ 5, it is shown that the graph obtained from the n‐cycle by joining vertices at distance 2 has a 2‐factorization is which one 2‐factor is a Hamilton cycle, and the other is isomorphic to any given 2‐regular graph of order n. This result is used to prove several results on 2‐factorizations of the complete graph Kn of order n. For example, it is shown that for all odd n ≥ 11, Kn has a 2‐factorization in which three of the 2‐factors are isomorphic to any three given 2‐regular graphs of order n, and the remaining 2‐factors are Hamilton cycles. For any two given 2‐regular graphs of even order n, the corresponding result is proved for the graph Kn ‐ I obtained from the complete graph by removing the edges of a 1‐factor. © 2004 Wiley Periodicals, Inc.
Even cycles in graphs
Authors: Conlon Joseph G. 
Published: January 2004

AbstractLet G be a 3‐connected simple graph of minimum degree 4 on at least six vertices. The author proves the existence of an even cycle C in G such that G‐V(C) is connected and G‐E(C) is 2‐connected. The result is related to previous results of Jackson, and Thomassen and Toft. Thomassen and Toft proved that G contains an induced cycle C such that both G‐V(C) and G‐E(C) is 2‐connected. G does not in general contain an even cycle such that G‐V(C) is 2‐connected. © 2004 Wiley Periodicals, Inc. J Graph Theory 45: 163–223, 2004
Growth of Self‐Similar Graphs
Authors: Krön B. 
Published: January 2004

AbstractLocally finite self‐similar graphs with bounded geometry and without bounded geometry as well as non‐locally finite self‐similar graphs are characterized by the structure of their cell graphs. Geometric properties concerning the volume growth and distances in cell graphs are discussed. The length scaling factor ν and the volume scaling factor μ can be defined similarly to the corresponding parameters of continuous self‐similar sets. There are different notions of growth dimensions of graphs. For a rather general class of self‐similar graphs, it is proved that all these dimensions coincide and that they can be calculated in the same way as the Hausdorff dimension of continuous self‐similar fractals: ${\rm dim}\ X={{\rm log}\ \mu \over {\rm log}\ \nu }$. © 2004 Wiley Periodicals, Inc. J Graph Theory 45: 224–239, 2004
Hepatitis B virus genotypes and spontaneous hepatitis B e antigen seroconversion in Taiwanese hepatitis B carriers
Authors: Kao Jia‐Horng , Chen Pei‐Jer , Lai Ming‐Yang , Chen Ding‐Shinn 
Published: January 2004

AbstractHepatitis B virus (HBV) is classified into eight genotypes (A–H), and genotype C is associated with more aggressive liver disease compared to genotype B. However, the mechanisms responsible for the clinical differences remain unclear. To test whether genotype C patients had with lower rates of spontaneous hepatitis B ge antigen (HBeAg) seroconversion than genotype B patients, stored serum samples from 146 Taiwanese adult HBeAg‐positive hepatitis B carriers followed‐up for a mean of 52 months (range, 12–120 months) were tested for HBV genotype by a molecular method. Genotype C patients were significantly older than genotype B patients (mean age, 37 ± 12 vs. 29 ± 10 years, P < 0.001). During the follow‐up period, genotype C patients had a significantly lower rate of spontaneous HBeAg seroconversion than genotype B patients (27 vs. 47%, P < 0.025). Spontaneous HBeAg seroconversion occurred one decade later in genotype C patients compared with genotype B patients. Multivariate analyses identified age ≤35 years (odds ratio: 2.08; 95% confidence interval [CI], 1.07–4.0; P < 0.05), high baseline serum alanine aminotransferase level (odds ratio: 2.34; 95%CI, 1.39–4.09; P < 0.005), and HBV genotype B (odds ratio: 1.94; 95%CI, 1.03–3.63; P < 0.05) as independent factors associated with spontaneous HBeAg seroconversion. In conclusion, genotype C patients, compared to genotype B patients, have a delayed HBeAg seroconversion in the immune clearance phase of chronic HBV infection, which may contribute to a more progressive liver disease and more refractory to antiviral therapy. J. Med. Virol. 72:363–369, 2004. © 2004 Wiley‐Liss, Inc.
HIV epidemic in central african republic: High prevalence rates in both rural and urban areas
Authors: Matsika‐Claquin Marcelle Diane , Massanga Marcel , Ménard Didier , Mazi‐Nzapako Jean , Ténegbia Jean‐Pierre , Mandeng Marie‐Joëlle , Willybiro‐Sacko Jean , Fontanet Arnaud , Talarmin Antoine 
Published: January 2004

AbstractA sentinel serosurveillance study was conducted in Central African Republic to estimate the prevalence of HIV seropositivity in the general adult population in each province so that the public health authorities can target HIV prevention programmes to the priority areas. Blood samples were collected from women attending 48 antenatal clinics in urban and rural areas of the Central African Republic. These samples were tested for HIV antibodies in an anonymous and unlinked manner using strategy II recommended by WHO. The data were extrapolated to all women of reproductive age in Central African Republic by use of a parity‐based adjustment involving the application of correction factors to the observed prevalence rates. A total of 9,305 pregnant women were recruited from November 2001 to October 2002. HIV seroprevalence was high in all age groups (12% in the less than 20 year age group to 17% in the 25–29 year age group). The median prevalence of HIV in antenatal clinics was similar for rural areas, for Bangui and for other urban areas (16.5, 15.0, and 12.5% respectively). Adjustment for parity and fertility pattern increased the prevalence of HIV in all antenatal clinics except in Bangui. This first national study of HIV prevalence in Central African Republic revealed that the HIV epidemic is continuing to spread in both urban and rural areas. Thus, efforts to reduce transmission should be made in every part of the country. J. Med. Virol. 72:358–362, 2004. © 2004 Wiley‐Liss, Inc.
Characterization of mimotopes mimicking an immunodominant conformational epitope on the hepatitis C virus NS3 helicase
Authors: Jolivet‐Reynaud Colette , Adida Anne , Michel Sandrine , Deléage Gilbert , Paranhos‐Baccala Glaucia , Gonin Virginie , Battail‐Poirot Nicole , Lacoux Xavier , Rolland Dominique 
Published: January 2004

AbstractThe hepatitis C virus (HCV) nonstructural 3 (NS3) protein is composed of an amino terminal protease and a carboxyl terminal RNA helicase. NS3 contains major antigenic epitopes. The antibody response to NS3 appears early in the course of infection and is focused on the helicase region. However, this response cannot be defined by short synthetic peptides indicating the recognition of conformation‐dependent epitopes. In this study, we have screened a dodecapeptide library displayed on phage with anti‐NS3 mouse monoclonal antibodies (mAbs) that compete with each other and human anti‐HCV NS3 positive sera. Two peptides (mimotopes) were selected that appeared to mimic an immunodominant epitope since they were recognized specifically by the different anti‐NS3 mAbs of the study and by human sera from HCV infected patients. Homology search between the two mimotopes and the NS3 sequence showed that one of the two peptides shared amino acid similarities with NS3 at residues 1396–1398 on a very accessible loop as visualized on the three‐dimensional structure of the helicase domain whereas the other one had two amino acids similar to nearby residues 1376 and 1378. Reproduced as synthetic dodecapeptides, the two mimotopes were recognized specifically by 19 and 22, respectively, out of 49 sera from HCV infected patients. These mimotopes allowed also the detection of anti‐NS3 antibodies in sera of HCV patients at the seroconversion stage. These results suggest that the two NS3 mimotopes are potential tools for the diagnosis of HCV infection. J. Med. Virol. 72:385–395, 2004. © 2004 Wiley‐Liss, Inc.
Simultaneous detection and differentiation of human polyomaviruses JC and BK by a rapid and sensitive PCR‐ELAHA assay and a survey of the JCV subtypes within an Australian population
Authors: Whiley David M. , Arden Katherine E. , Mackay Ian M. , Syrmis Melanie W. , Sloots Theo P. 
Published: January 2004

AbstractHuman polyomaviruses JCV and BKV can cause several clinical manifestations in immunocompromised hosts, including progressive multifocal leukoencephalopathy (PML) and haemorrhagic cystitis. Molecular detection by polymerase chain reaction (PCR) is recognised as a sensitive and specific method for detecting human polyomaviruses in clinical samples. In this study, we developed a PCR assay using a single primer pair to amplify a segment of the VP1 gene of JCV and BKV. An enzyme linked amplicon hybridisation assay (ELAHA) using species‐specific biotinylated oligonucleotide probes was used to differentiate between JCV and BKV. This assay (VP1‐PCR‐ELAHA) was evaluated and compared to a PCR assay targeting the human polyomavirus T antigen gene (pol‐PCR). DNA sequencing was used to confirm the polyomavirus species identified by the VP1‐PCR‐ELAHA and to determine the subtype of each JCV isolate. A total of 297 urine specimens were tested and human polyomavirus was detected in 105 specimens (35.4%) by both PCR assays. The differentiation of JCV and BKV by the VP1‐PCR‐ELAHA showed good agreement with the results of DNA sequencing. Further, DNA sequencing of the JCV positive specimens showed the most prevalent JCV subtype in our cohort was 2a (27%) followed by 1b (20%), 1a (15%), 2c (14%), 4 (14%) and 2b (10%). The results of this study show that the VP1‐PCR‐ELAHA is a sensitive, specific and rapid method for detecting and differentiating human polyomaviruses JC and BK and is highly suitable for routine use in the clinical laboratory. J. Med. Virol. 72:467–472, 2004. © 2004 Wiley‐Liss, Inc.
Effects of potent antiretroviral therapy on the immune activation marker soluble CD27 in patients infected with HIV‐1 subtypes A–D
Authors: Atlas Ann , Thanh Ha Tran Thi , Lindström Anna , Nilsson Anna , Alaeus Annette , Chiodi Francesca , De Milito Angelo 
Published: January 2004

AbstractHIV‐1 genetic subtypes might have a different impact on disease progression and response to antiretroviral therapy (ART). Few data are available on the immune activation profile in patients with different HIV‐1 subtypes. We have tested by ELISA the plasma levels of an immune activation marker, soluble CD27 (sCD27), in a cohort of 64 patients infected with HIV‐1 subtypes A–D, at baseline and after 1 year of virologically successful ART. Plasma sCD27 was significantly higher in the whole HIV‐1‐infected population as compared to healthy subjects [522 U/ml (188–1,307) vs. 285 U/ml (174–397), P < 0.001]. Among the four different HIV‐1 subtypes, patients with subtype C virus had significantly higher plasma sCD27 [684 U/ml, (188–1228)] as compared to patients with subtype A [428 U/ml (247–1307), P < 0.05] and B [454 (211–925), P < 0.05]. After 1 year of ART, plasma sCD27 significantly decreased in all groups but patients with subtype C viruses had the largest reduction of sCD27 from baseline. The data indicate that a similar immune activation profile is present in patients infected with HIV‐1 subtypes A, B, and D and that in presence of successful ART these subtypes respond similarly in terms of immune activation. Intriguingly, subtype C infection seems to be associated with higher levels of plasma sCD27, suggesting that HIV‐1 genetic subtype C may have a different impact on disease outcome and response to therapy. J. Med. Virol. 72:345–351, 2004. © 2004 Wiley‐Liss, Inc.
Elevation of soluble VCAM‐1 plasma levels in children with acute dengue virus infection of varying severity
Authors: Koraka Penelopie , Murgue Bernadette , Deparis Xavier , van Gorp Eric C.M. , Setiati Tatty E. , Osterhaus Albert D.M.E. , Groen Jan 
Published: January 2004

AbstractApproximately 1,000 million infections with dengue viruses are estimated to occur annually. The majority of the cases develop mild disease, whereas only small proportion of the infected individuals develop severe hemorrhagic manifestations at the end of the acute phase of illness. In this study, the value of plasma levels of vascular cell adhesion molecule 1 (VCAM‐1) in the pathogenesis and prognosis of dengue illness was investigated in children with dengue infections of varying severity. The plasma levels of soluble VCAM‐1 (sVCAM‐1) were measured in serial plasma samples obtained from 168 children aged between 7 months and 14 years with confirmed dengue infection. Of those children, 71 were suffering from dengue fever, 30 were suffering from dengue hemorrhagic fever, and 67 were suffering from dengue shock syndrome. Plasma samples obtained from 21 patients with febrile illness other than dengue served as controls. A commercially available kit (R&D Systems, Oxon, UK) was used to measure the levels of sVCAM‐1 in plasma samples. sVCAM‐1 was elevated during acute dengue infection, and significantly elevated among dengue shock syndrome patients as compared to dengue fever or dengue hemorrhagic fever patients (P < 0.05). Statistical analysis revealed that sVCAM‐1 was associated with dengue disease severity and the time post infection (acute vs. convalescent phase) and not with age, sex, or previous exposure of the patients to dengue infection. A significant difference was found in the plasma levels of sVCAM‐1 between dengue shock syndrome and dengue fever patients, however, the prognostic value of this marker in the acute stage of dengue illness proved to be limited. These data also favor to study the further elucidation of the role of sVCAM‐1 in the pathogenesis of dengue infections. J. Med. Virol. 72:445–450, 2004. © 2004 Wiley‐Liss, Inc.
Increased detection of rotavirus using a real time reverse transcription‐polymerase chain reaction (RT‐PCR) assay in stool specimens from children with diarrhea
Authors: Pang Xiaoli L. , Lee Bonita , Boroumand Nasim , Leblanc Barbara , Preiksaitis Jutta K. , Yu Ip Charlotte C. 
Published: January 2004

AbstractSix‐hundred and twenty‐six stool specimens collected from children with diarrhea over a 12‐month period were tested for rotavirus using a real time reverse transcription‐polymerase chain reaction (RT‐PCR) assay, a conventional nested PCR assay and by electron microscopy (EM). A fragment of 87 bp in a highly‐conserved region of non‐structural protein 3 (NSP3) in rotavirus genome was amplified by a single‐step RT‐PCR protocol in a closed‐tube system. Rotavirus was detected in 123 samples (20%) with the real time RT‐PCR assay, 113 samples (18%) with the nested‐PCR assay, and 79 samples (13%) with EM. Using serial diluted nucleic acid extract, we compared the sensitivity of real time RT‐PCR with conventional RT‐PCR and conventional nested PCR assays. Real time RT‐PCR was two to four logs more sensitive than the conventional assays. The reaction time required for the RT‐PCR assay is about half the time required for the conventional nested‐PCR. The real time RT‐PCR assay is both simple and rapid with advantages including enhanced sensitivity and a lower risk for cross‐contamination making it a useful tool for the detection of rotavirus in various situations including sporadic gastroenteritis, outbreaks, and environmental investigations. G1 was the predominant type (89%), followed by G2 (10%), and G4 (1%). No rotavirus of G3, G8, and G9 types were found. The peak season for rotavirus infection was January to May in northern Alberta. J. Med. Virol. 72:496–501, 2004. © 2004 Wiley‐Liss, Inc.
Different resistance mutations can be detected simultaneously in the blood and the lung of HIV‐1 infected individuals on antiretroviral therapy
Authors: White Natalie C. , Israel‐Biet Dominique , Coker Richard J. , Mitchell David M. , Weber Jonathan N. , Clarke John R. 
Published: January 2004

AbstractIn this retrospective study, matched peripheral blood and lung samples from patients on antiretroviral therapy were studied in order to investigate whether differences in mutations associated with resistance to nucleoside analogues could be detected between the lung and blood. Discordant mutation patterns in the reverse transcriptase (RT) between plasma and cell free bronchoalveolar lavage fluid (BAL‐fluid) HIV‐1 genomic RNA was observed in five out of seven patients on nucleoside reverse transcriptase inhibitor (NRTI) monotherapy and six out of seven on combination therapy. In the cellular compartments, DNA recovered from peripheral blood mononuclear cells (PBMCs) and cells from BAL‐cells discordant HIV‐1 resistance genotypes were detected in 15 out of 44 matched samples. Differences in resistant genotypes between PBMCs and BAL‐cells were most pronounced in patients receiving combination antiretroviral therapy. The pattern and number of mutations in RT associated with resistance differed in the BAL‐cells compared to PBMCs in four out of 12 subjects not receiving antiretroviral therapy at the time of bronchoscopy, three from 14 patients on NRTI monotherapy, five out of nine on dual combination therapy and three out of nine on HAART. The differences in the detection of resistance mutations between blood and the lung suggest that the lung is a site of replication for HIV‐1. J. Med. Virol. 72:352–357, 2004. © 2004 Wiley‐Liss, Inc.
Human herpesvirus‐8 infection in pregnancy and labor: Lack of evidence of vertical transmission
Authors: Sarmati Loredana , Carlo Ticconi , Rossella Santangelo , Montano Marco , Adalgisa Pietropolli , Rezza Giovanni , Andreoni Massimo 
Published: January 2004

AbstractTo investigate whether vertical transmission of the human herpesvirus 8 (HHV‐8) may occur during pregnancy or at delivery, we enrolled 295 women recruited attending the Division of Obstetrics and Gynecology of a University Teaching of Rome Tor Vergata, S. Eugenio Hospital. The study population was divided in two groups: 245 pregnant women who underwent amniocentesis for genetic screening at 16–18 weeks gestation (group 1) and 50 women at the childbirth (group 2). Maternal blood was obtained from all women. Amniotic fluid (group 1) and cord blood (group 2) were obtained at midtrimester and at delivery, respectively. The presence of anti‐HHV‐8 antibodies in serum samples was investigated by an immunfluorescence assay. All amniotic fluids, maternal blood, and cord blood samples from HHV‐8 seropositive women were tested for the presence of HHV‐8 DNA sequences by the polymerase chain reaction. Thirty women, 27 of the group 1 and three of the group 2, were found to have anti‐HHV‐8 antibodies. Two neonates of the three seropositive mothers of the group 2 had anti‐HHV‐8 antibodies in cord blood. HHV‐8 DNA sequences were detected in the blood of one woman of the group 2. None of the amniotic fluid and cord blood samples had detectable HHV‐8 DNA sequences. This study suggests that vertical transmission of HHV‐8 is unlikely or, at least, very rare. J. Med. Virol. 72:462–466, 2004. © 2004 Wiley‐Liss, Inc.
Detection and genotyping of TT virus in healthy and subjects with HBV or HCV in different populations in the United Arab Emirates
Authors: Al‐Moslih Moslih I. , Abuodeh Raed O. , Hu Yu‐Wen 
Published: January 2004

AbstractTT virus (TTV) and TTV‐like viruses (TTVLs) have been reported to be associated with non‐A–E hepatitis. To determine the rate of infection and genotypic characteristics of TTV in the United Arab Emirates (UAE), a total of 449 serum samples representing different populations in the UAE and comprising healthy as well as patients positive for HBsAg and HCV were screened. National subjects (n = 200) and non‐nationals residing in the UAE (n = 249) were tested by PCR. The results obtained showed that the rate of TTV infection in healthy nationals, and those with HBsAg or antibody to HCV were 34.9, 97.9, and 95.7, respectively, compared to 89.1% (115/129), 89.2% (66/74), and 84.8% (39/46), respectively, in non‐nationals. Sequence analysis of the untranslated region (UTR) using 71 clones generated from the PCR products of eight serum samples from healthy individuals (four nationals and four non‐nationals) showed that 83.1% of the TTV clones were classified into groups 1–4, whereas 16.9% into possibly new genotype(s). The analysis also revealed that healthy national subjects carried multiple viruses. Phylogenetic analysis of representative sequences revealed clustering of clones into at least five major groups. Also, when compared to reference genotypes (from GenBank), two of our clones belonged to two previously identified genotypes. Non‐significant gender differences were seen in all ethnic groups studied (P > 0.05). In conclusion, the rate of TTV infection in the UAE nationals is significantly lower (P < 0.05) than that of the non‐nationals and several genotypes were isolated with common multi‐infections. J. Med. Virol. 72: 502–508, 2004. © 2004 Wiley‐Liss, Inc.
Measurement of antirotavirus IgM/IgA/IgG responses in the serum samples of Indian children following rotavirus diarrhoea and their mothers
Authors: Ray Pratibha G. , Kelkar Shobhana D. 
Published: January 2004

AbstractRotavirus specific, serum IgM/IgA/IgG levels among hospitalized children and their respective mothers were determined. Children were grouped as having rotavirus diarrhoea (RVD) and non‐rotavirus diarrhoea (NRVD) on the basis of fecal excretion measured by ELISA and RT‐PCR. Although IgM seropositivity was observed among children of both the groups, it was significantly higher in the acute as well as convalescent phase serum samples (P < 0.05 for both) of RVD group. Five out of ten acute sera from the NRVD group were positive for IgM and seven showed IgA/IgG seroconversion indicating rotavirus infection among these children in the past. It was noted that, three out of 24 mothers' sera from RVD group, showed presence of IgM in the serum collected during convalescence of their children. The observation suggests, subclinical rotavirus infection among mothers probably contacted from their children. This is supported by the seroconversion for IgA/IgG among these three mothers. Such a phenomenon was not noticed among the mothers from NRVD group. In general, IgA positivity did not vary significantly among the children from both the groups. IgA seropositivity was significantly higher (P < 0.001) from children of RVD group as compared to healthy group of children following rotavirus infection. From RVD group, all the child patients and 12 mothers out of 24 (50%) showed IgA/IgG seroconversion. None of the mothers from NRVD group showed seroconversion. Serum samples of healthy children and adults, showed IgM positivity at equal level (10%), but a significant difference (P < 0.01) was observed in IgA positivity. In conclusion, subclinical transmission of rotavirus infection from children to their mothers may occur. Seroconversion alone cannot be considered as a marker of rotavirus diarrhoea in children. Moreover, about 40–50% of subjects lacked rotavirus specific IgA at protective levels, making them susceptible to rotavirus infection. J. Med. Virol. 72:416–423, 2004. © 2004 Wiley‐Liss, Inc.