bluuebunny/crossref_metadata_2025_split huggingface dataset:
Nationwide Survey Shows that Methicillin-Resistant
Staphylococcus aureus
Strains Heterogeneously and Intermediately Resistant to Vancomycin Are Not Disseminated throughout Japanese Hospitals
Authors: Ike Yasuyoshi , Arakawa Yoshichika , Ma Xinghua , Tatewaki Kenichi , Nagasawa Mitsuaki , Tomita Haruyoshi , Tanimoto Koichi , Fujimoto Shuhei 
Published: July 2002

ABSTRACT

A total of 6,625 methicillin-resistant
Staphylococcus aureus
(MRSA) clinical isolates obtained from 278 hospitals throughout Japan were obtained between November and December 1997 and were examined for their sensitivities to vancomycin using Mueller Hinton (MH), brain heart infusion (BHI), agar plates, or the broth microdilution method. A concentrated inoculum of an MRSA strain or the use of highly enriched medium, such as BHI medium, allows an individual cell to grow on agar plates containing a vancomycin concentration greater than the MIC for the parent strain. However, cells of the colonies which grew on BHI agar plates containing the higher vancomycin concentrations did not acquire a level of vancomycin resistance greater than that of the parent strain and were not subpopulations of heterogeneously vancomycin-resistant MRSA. There was no significance in the fact that these colonies grew on the higher concentration of vancomycin: none showed stable resistance to vancomycin at a concentration above the MIC for the parent strain, and no cell from these colonies showed a relationship between the MIC and the ability of these colonies to grow on higher concentrations of vancomycin. The vancomycin MIC was not above 2 μg/ml for any of the cells originating from these colonies. No Mu3-type heterogeneously resistant MRSA strains, which constitutively produce subpopulations from MRSA clinical isolates with intermediate vancomycin resistance at a high frequency, were detected. There was a unipolar distribution of the MICs ranging from 0.25 to 2 μg of vancomycin/ml among the 6,625 MRSA clinical isolates, indicating that there was no Mu50-type intermediately vancomycin-resistant MRSA (MIC, 8 μg/ml by National Committee for Clinical Laboratory Standards criteria) among the clinical isolates, and there was no evidence of dissemination of Mu3-type MRSA heteroresistant to vancomycin.
Identification, Classification, and Phylogeny of the Pathogenic SpeciesExophiala jeanselmeiand Related Species by Mitochondrial CytochromebGene Analysis
Authors: Wang Li , Yokoyama Koji , Miyaji Makoto , Nishimura Kazuko 
Published: July 2002

ABSTRACTWe analyzed a 402-bp sequence of the mitochondrial cytochromebgene of 34 strains ofExophiala jeanselmeiand 16 strains representing 12 related species. The strains ofE.jeanselmeiwere classified into 20 DNA types and 17 amino acid types. The differences between these strains were found in 1 to 60 nucleotides and 1 to 17 amino acids. On the basis of the identities and similarities of nucleotide and amino acid sequences, some strains were reidentified: i.e., two strains ofE.jeanselmeivar.hetermorphaand one strain ofE.castellaniiasE.dermatitidis(including the type strain), three strains ofE.jeanselmeiasE.jeanselmeivar.lecanii-corni(including the type strain), three strains ofE.jeanselmeiasE.bergeri(including the type strain), seven strains ofE.jeanselmeiasE.pisciphila(including the type strain), seven strains ofE.jeanselmeiasE.jeanselmeivar.jeanselmei(including the type strain), one strain ofE.jeanselmeiasFonsecaea pedrosoi(including the type strain), and one strain ofE.jeanselmeiasE.spinifera(including the type strain). SomeE.jeanselmeistrains showed distinct nucleotide and amino acid sequences. The amino-acid-based UPGMA (unweighted pair group method with the arithmetic mean) tree exhibited nearly the same topology as those of the DNA-based trees obtained by neighbor joining, maximum parsimony, and maximum likelihood methods.
Maxillary Sinusitis Caused by
Actinomucor elegans
Authors: Davel Graciela , Featherston Patricia , Fernández Anibal , Abrantes Ruben , Canteros Cristina , Rodero Laura , Sztern Carlos , Perrotta Diego 
Published: July 2002

ABSTRACT

We report the first case of maxillary sinusitis caused by
Actinomucor elegans
in an 11-year-old patient. Histopathological and mycological examinations of surgical maxillary sinuses samples showed coenocytic hyphae characteristic of mucoraceous fungi. The fungi recovered had stolons and rhizoids, nonapophyseal and globose sporangia, and whorled branched sporangiophores and was identified as
A. elegans
. After surgical cleaning and chemotherapy with amphotericin B administered intravenously and by irrigation, the patient became asymptomatic and the mycological study results were negative.
Vancomycin-Resistant
Enterococcus faecium
Strain Carrying the
vanB2
Gene Variant in a Polish Hospital
Authors: Kawalec Magdalena , Gniadkowski Marek , Zielińska Urszula , Kłos Waldemar , Hryniewicz Waleria 
Published: July 2002

ABSTRACT

About 2.5 years after the first isolation of the VanA phenotype of vancomycin-resistant
Enterococcus faecium
(VREM) in Poland, the first VREM strains with the VanB phenotype have emerged independently in two different Warsaw hospitals. In one of these the VREM strain was selected during the long-term antimicrobial treatment of a patient with a wide variety of infection risk factors who died after 3 months of hospitalization. The strain was found to contain the transferable
vanB2
gene cluster variant of the polymorphic type that was identified earlier in vancomycin-resistant enterococci from several different countries. In the course of infection the strain underwent genetic diversification due to DNA recombination.
Clinical Significance and Taxonomy ofActinobacillus hominis
Authors: Friis-Møller Alice , Christensen Jens Jørgen , Fussing Vivian , Hesselbjerg Annemarie , Christiansen Jytte , Bruun Brita 
Published: July 2002

ABSTRACTClinical findings in 36 immunosuppressed patients with lower respiratory tract infection or bacteremia withActinobacillus hominisare described. Animal contact was only recorded for three patients; nine patients died despite appropriate antimicrobial treatment. Although infections with this microorganism seem to be rare, the fact that 37 of 46 strains characterized in this study have been found in Copenhagen indicates that under-reporting may occur.A. hominisis phenotypically relatively homogeneous but can be difficult to differentiate from otherActinobacillusspecies unless extensive biochemical testing is performed. Mannose-positive strains ofA. hominisare especially difficult to differentiate fromA. equuli. Attempts to identifyA. hominisby automatic identification systems may lead to misidentifications. Ribotyping and DNA-DNA hybridization data show thatA. hominisis a homogeneous species clearly separated from other species within the genusActinobacillus.
Performance of the Applied Biosystems ViroSeq Human Immunodeficiency Virus Type 1 (HIV-1) Genotyping System for Sequence-Based Analysis of HIV-1 in Pediatric Plasma Samples
Authors: Cunningham Shawn , Ank Bonnie , Lewis Dan , Lu Wei , Wantman Michael , Dileanis JoAnn , Jackson J. Brooks , Palumbo Paul , Krogstad Paul , Eshleman Susan H. 
Published: July 2002

ABSTRACT
The ViroSeq HIV-1 Genotyping System is a commercially available, integrated sequence-based system for analysis of human immunodeficiency virus type 1 (HIV-1) drug resistance. We evaluated the performance of this system by analyzing HIV-1 in pediatric plasma samples. Plasma samples from children 4 months to 17 years of age were obtained from a clinical trial protocol (PACTG 377). Children in PACTG 377 were randomized to four treatment arms, including different combinations of antiretroviral drugs. HIV-1 genotyping was performed using samples collected prior to antiretroviral therapy (baseline) and at the time of virologic failure. Performance of the genotyping system was compared in three university laboratories. A total of 196 samples were analyzed, including 135 baseline and 61 failure samples. Plasma volumes ranged from 0.05 to 0.5 ml, and viral loads ranged from 1,084 to 3,484,991 copies/ml. PCR products suitable for sequencing were obtained for 192 of the 196 samples. Complete sequences for protease and reverse transcriptase were obtained for all of these 192 samples. For 180 samples, data were obtained from both DNA strands for the entire region analyzed. There was no evidence of sample cross-contamination based on phylogenetic analysis of HIV-1 sequences. Performance of the genotyping system was similar in three laboratories. This genotyping system performs well for analysis of HIV-1 in pediatric plasma samples, including those with low volume and low viral load. The availability of this system should facilitate studies of HIV-1 drug resistance.
Prevalence of CongenitalToxoplasma gondiiInfection among Newborns from the Poznań Region of Poland: Validation of a New Combined Enzyme Immunoassay forToxoplasma gondii-Specific Immunoglobulin A and Immunoglobulin M Antibodies
Authors: Paul Małgorzata , Petersen Eskild , Szczapa Jerzy 
Published: July 2002

ABSTRACTWe determined the value of a new serological assay detectingToxoplasma-specific immunoglobulin M (IgM) and IgA antibodies at birth for use in mass neonatal screening. The incidence of congenital infection in newborns was compared with data from an epidemiological investigation on the seroprevalence ofToxoplasmain the studied population. Peripheral blood was collected on Guthrie cards during the first 3 days of life and tested for anti-ToxoplasmaIgA and IgM using a noncommercial immunocapture enzyme-linked immunosorbent assay (ELISA). When the screening assay was positive, serum samples from the child and the mother were collected for use in Western blotting comparative immunological profile analysis and traditional serological tests for determination of specific IgG, IgM, and IgA antibodies. From December 1998 to April 2000, 17,653 filter paper samples from live-born neonates were successively screened. CongenitalT. gondiiinfection was finally confirmed in 19 newborns. In traditional assays, 13 of 19 infants were IgM and IgA positive using filter paper eluates at birth, 1 child was positive only for IgM, 1 patient was positive for IgM and borderline for IgA, 1 had an equivocal level of IgA, and 3 cases were confirmed only by the Western blot assay. The prevalence ofToxoplasma-specific IgA and/or IgM in filter paper samples at birth was 1 per 929 live-born neonates (1.08/1,000) or about 1 per 523 children (1.9/1,000) born to nonimmune women with a potential risk of primaryT. gondiiinfection during pregnancy, compared to the actual seropositivity rate of 43.7%. The diagnostic sensitivity of the combined IgA-IgM ELISA using neonatal filter paper specimens was not more than 95%, the positive predictive value of the test was 82.6%, and the diagnostic specificity was calculated to be 99.9%. The combined IgA-IgM ELISA is a valuable method for the diagnosis of congenital toxoplasmosis at birth and fulfills criteria for neonatal screening programs. The method showed a good diagnostic sensitivity in neonates untreated prenatally who were born in an area of high seroprevalence ofT. gondiiinfection.
Fulminant Japanese Spotted Fever Associated with Hypercytokinemia
Authors: Iwasaki Hiromichi , Mahara Fumihiko , Takada Nobuhiro , Fujita Hiromi , Ueda Takanori 
Published: July 2002

ABSTRACT

We report a patient with Japanese spotted fever caused by
Rickettsia japonica
who developed shock associated with hypercytokinemia. Elevated levels of cytokines (macrophage colony-stimulating factor, interleukin 1 beta, interleukin 10, and gamma interferon) decreased rapidly after a combination treatment using an antibiotic (minocycline hydrochloride [MINO]) and methylprednisolone; however, tumor necrosis factor alpha levels were increased. The patient's fever relapsed and was resolved only after the addition of ciprofloxacin hydrochloride. The administration of new quinolones alone may be another useful form of treatment to eradicate
R. japonica
even if the symptoms of hypercytokinemia appear to improve with the administration of MINO and methylprednisolone.
Molecular Identification of a
Dietzia maris
Hip Prosthesis Infection Isolate
Authors: Pidoux O. , Argenson J.-N. , Jacomo V. , Drancourt M. 
Published: July 2002

ABSTRACT

Dietzia maris
, an environmental actinomycete, has been implicated only once in human disease. We herein report the first
D. maris
isolate from a bone biopsy specimen in a patient hospitalized for a total hip prosthesis replacement. Cell wall fatty acid analysis and 16S ribosomal DNA gene sequencing were utilized to achieve its definite identification. This case report illustrates the usefulness of such methods for the accurate identification of actinomycetes.
Identification of Aminoglycoside-Modifying Enzymes by Susceptibility Testing: Epidemiology of Methicillin-Resistant
Staphylococcus aureus
in Japan
Authors: Ida Takashi , Okamoto Ryoichi , Shimauchi Chieko , Okubo Toyoji , Kuga Akio , Inoue Matsuhisa 
Published: July 2002

ABSTRACT

A multiple-primer PCR was used to identify genes encoding aminoglycoside-modifying enzymes in 381 clinical isolates of methicillin-resistant
Staphylococcus aureus
(MRSA). The technique used three sets of primers delineating specific DNA fragments of the
aph(3′)-III, ant(4′)-I
, and
aac(6′)-aph(2")
genes, which influence the MICs of gentamicin, tobramycin, and lividomycin. Isolates with none of the three genes detected were susceptible to all three agents. Isolates with the
aph(3′)-III
gene showed resistance to lividomycin (MIC > 1,024 μg/ml), and those with the
ant(4′)-I
gene were resistant to tobramycin (MIC ≥ 8 μg/ml). Isolates with only the
aac(6′)-aph(2")
gene were resistant to gentamicin (MIC ≥ 8 μg/ml) and tobramycin in decreasing order; those with both the
ant(4′)-I
and
aac(6′)-aph(2")
genes also were resistant to gentamicin and tobramycin, but in increasing order. Susceptibility testing, then, could detect specific genes. In 381 Japanese MRSA isolates, the
ant(4′)-I, aac(6′)-aph(2")
, and
aph(3′)-III
genes were prevalent in 84.5, 61.7, and 8.9%, respectively. Isolates with only the
ant(4′)-I
gene had coagulase type II or III, but isolates with both the
ant(4′)-I
and
aac(6′)-aph(2")
genes included all coagulase types. Most isolates with coagulase type IV or VII carried the
aac(6′)-aph(2")
gene. Of the MRSA isolates with
ant(4′)-I
and/or
aac(6′)-aph(2")
genes, 97% were resistant to aminoglycosides in clinical use, but a new aminoglycoside, arbekacin, had excellent activity against these isolates.
Community-Acquired
Acinetobacter baumannii
Bacteremia in Adult Patients in Taiwan
Authors: Wang Jann-Tay , McDonald Lawrence Clifford , Chang Shan-Chwen , Ho Monto 
Published: July 2002

ABSTRACT

We determined the clinical and microbiologic characteristics of community-acquired
Acinetobacter baumannii
bacteremia in 19 adult patients. We found that malignancy was the most frequent underlying disease. The overall mortality rate was 58%. All 14 available isolates were identified as genomic species 2 (
A. baumannii
) by 16S ribosomal DNA sequencing and were found to be genetically distinct by pulsed-field gel electrophoresis.
Multilocus Sequence Typing for Characterization of Clinical and Environmental
Salmonella
Strains
Authors: Kotetishvili Mamuka , Stine O. Colin , Kreger Arnold , Morris, J. Glenn , Sulakvelidze Alexander 
Published: July 2002

ABSTRACT

Multilocus sequence typing (MLST) based on the 16S RNA,
pduF
,
glnA
, and
manB
genes was developed for
Salmonella
, and its discriminatory ability was compared to those of pulsed-field gel electrophoresis (PFGE) and serotyping. PFGE differentiated several strains undifferentiable by serotyping, and 78 distinct PFGE types were identified among 231
Salmonella
isolates grouped into 22 serotypes and 12 strains of undetermined serotype. The strains of several PFGE types were further differentiated by MLST, which suggests that the discriminatory ability of MLST for the typing of
Salmonella
is better than that of serotyping and/or PFGE typing.
manB
-based sequence typing identified two distinct genetic clusters containing 32 of 54 (59%) clinical isolates whose
manB
gene sequences were analyzed. The G+C contents and Splitstree analysis of the
manB
,
glnA
, and
pduF
genes of
Salmonella
indicated that the genes differ in their evolutionary origins and that recombination played a significant role in their evolution.
Evaluation of an Immunofluorescent-Antibody Test Using Monoclonal Antibodies Directed against
Enterocytozoon bieneusi
and
Encephalitozoon intestinalis
for Diagnosis of Intestinal Microsporidiosis in Bamako (Mali)
Authors: Alfa Cisse O. , Ouattara A. , Thellier M. , Accoceberry I. , Biligui S. , Minta D. , Doumbo O. , Desportes-Livage I. , Thera M. A. , Danis M. , Datry A. 
Published: July 2002

ABSTRACT

A 2-month study was carried out in Mali to evaluate an immunofluorescent-antibody test (IFAT) using monoclonal probes specific for
Enterocytozoon bieneusi
or
Encephalitozoon intestinalis
. Sixty-one human immunodeficiency virus (HIV)-seropositive adult patients and 71 immunocompetent children were enrolled. Microsporidia were detected in stools from 8 of 61 patients (13.1%) seropositive for HIV. A single species,
E. bieneusi
, was identified. All the children were negative for microsporidia. The sensitivity and specificity of IFAT were 100% compared with those of PCR, which was used as the “gold standard.” Moreover, species identification by IFAT was more rapid and less expensive than that by PCR. These results show the suitability of IFAT for detection of microsporidia in developing countries.
Parameters of Human Immunodeficiency Virus Infection of Human Cervical Tissue and Inhibition by Vaginal Virucides
Authors: Greenhead Peter , Hayes Peter , Watts Patricia S. , Laing Ken G. , Griffin George E. , Shattock Robin J. 
Published: July 2002

ABSTRACT
Heterosexual transmission of human immunodeficiency virus (HIV) is the most frequent mode of infection worldwide. However, the immediate events between exposure to infectious virus and establishment of infection are still poorly understood. This study investigates parameters of HIV infection of human female genital tissue in vitro using an explant culture model. In particular, we investigated the role of the epithelium and virucidal agents in protection against HIV infection. We have demonstrated that the major target cells of infection reside below the genital epithelium, and thus HIV must cross this barrier to establish infection. Immune activation enhanced HIV infection of such subepithelial cells. Furthermore, our data suggest that genital epithelial cells were not susceptible to HIV infection, appear to play no part in the transfer of infectious virus across the epithelium, and thus may provide a barrier to infection. In addition, experiments using a panel of virucidal agents demonstrated differential efficiency to block HIV infection of subepithelial cells from partial to complete inhibition. This is the first demonstration that virucidal agents designed for topical vaginal use block HIV infection of genital tissue. Such agents have major implications for world health, as they will provide women with a mechanism of personal and covert protection from HIV infection.
Soluble Receptor-Induced Retroviral Infection of Receptor-Deficient Cells
Authors: Damico Rachel , Bates Paul 
Published: July 2002

ABSTRACT
Current models of retroviral entry hypothesize that interactions between the host cell receptor(s) and viral envelope protein induce structural changes in the envelope protein that convert it to an active conformation, allowing it to mediate fusion with the membrane. Recent evidence supporting this hypothesis is the demonstration that Tva, the receptor for subgroup A avian sarcoma and leukosis virus (ASLV-A), induces conformational changes in the viral envelope protein. These changes include conversion of the envelope protein to an active, membrane-binding state likely representing a fusogenic conformation. To determine whether binding of the soluble Tva (sTva) receptor was sufficient to activate fully the fusogenic potential of the ASLV-A envelope protein, we have evaluated the ability of ASLV-A to infect receptor-deficient cell lines in the presence of sTva. Soluble receptor efficiently mediated infection of cells devoid of endogenous Tva in a dose-dependent manner, and this infection was dependent absolutely on the addition of sTva. The infectivity of the virus was enhanced dramatically in the presence of the polycationic polymer Polybrene or when centrifugal forces were applied during inoculation, resulting in viral titers comparable to those achieved on cells expressing endogenous receptor. sTva functioned to mediate infection at low concentrations, approaching the estimated binding constant of the receptor and viral envelope protein. These results demonstrate that receptor binding can activate the ASLV-A envelope protein and convert it to a fusogenic conformation competent to mediate the fusion of the viral and cellular membranes.
Phosphorylation of Human Immunodeficiency Virus Type 1 Vpr Regulates Cell Cycle Arrest
Authors: Zhou Yi , Ratner Lee 
Published: July 2002

ABSTRACT

Human immunodeficiency virus type 1 (HIV-1) Vpr regulates nuclear transport of the viral preintegration complex, G
2
cell cycle arrest, and transcriptional transactivation. We asked whether phosphorylation could affect Vpr activity. Vpr was found to be phosphorylated on serine residues in transiently transfected and infected cells. Residues 79, 94, and 96 were all found to be phosphorylated, as assessed by alanine mutations. Mutation of Ser-79 to Ala abrogated effects of Vpr on cell cycle progression, whereas mutation of Ser-94 and Ser-96 had no effect. Simultaneous mutation of all three Vpr serine residues attenuated HIV-1 replication in macrophages, whereas single and double Ser mutations had no effect.
Origin of Hepatitis Delta Virus mRNA
Authors: Gudima Severin , Wu Shwu-Yuan , Chiang Cheng-Ming , Moraleda Gloria , Taylor John 
Published: July 2002

ABSTRACT
Hepatitis delta virus (HDV) is unique relative to all known animal viruses, especially in terms of its ability to redirect host RNA polymerase(s) to transcribe its 1,679-nucleotide (nt) circular RNA genome. During replication there accumulates not only more molecules of the genome but also its exact complement, the antigenome. In addition, there are relatively smaller amounts of an 800-nt RNA of antigenomic polarity that is polyadenylated and considered to act as mRNA for translation of the single and essential HDV protein, the delta antigen. Characterization of this mRNA could provide insights into the in vivo mechanism of HDV RNA-directed RNA transcription and processing. Previously, we showed that the 5′ end of this RNA was located in the majority of species, at nt 1630. The present studies show that (i) at least some of this RNA, as extracted from the liver of an HDV-infected woodchuck, behaved as if it contained a 5′-cap structure; (ii) in the infected liver there were additional polyadenylated antigenomic HDV RNA species with 5′ ends located at least 202 nt and even 335 nt beyond the nt 1630 site, (iii) the 5′ end at nt 1630 was not detected in transfected cells, following DNA-directed HDV RNA transcription, in the absence of genome replication, and (iv) nevertheless, using in vitro transcription with purified human RNA polymerase II holoenzyme and genomic RNA template, we did not detect initiation of template-dependent RNA synthesis; we observed only low levels of 3′-end addition to the template. These new findings support the interpretation that the 5′ end detected at nt 1630 during HDV replication represents a specific site for the initiation of an RNA-directed RNA synthesis, which is then modified by capping.