bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comparative In Vitro Activities of GAR-936 against Aerobic and Anaerobic Animal and Human Bite Wound Pathogens
Authors: Goldstein Ellie J. C. , Citron Diane M. , Merriam C. Vreni , Warren Yumi , Tyrrell Kerin 
Published: July 2002

ABSTRACT

GAR-936 is a new semisynthetic glycylcycline with a broad antibacterial spectrum, including tetracycline-resistant strains. The in vitro activities of GAR-936, minocycline, doxycycline, tetracycline, moxifloxacin, penicillin G, and erythromycin were determined by agar dilution methods against 268 aerobic and 148 anaerobic strains of bacteria (including
Pasteurella
,
Eikenella
,
Moraxella
,
Bergeyella
,
Neisseria
, EF-4,
Bacteroides
,
Prevotella
,
Porphyromonas
,
Fusobacterium
,
Staphylococcus
,
Streptococcus
,
Enterococcus
,
Corynebacterium
,
Propionibacterium
,
Peptostreptococcus
, and
Actinomyces
) isolated from infected human and animal bite wounds in humans, including strains resistant to commonly used antimicrobials. GAR-936 was very active, with an MIC at which 90% of the strains are inhibited (MIC
90
) of ≤0.25 μg/ml, against all aerobic gram-positive and -negative strains, including tetracycline-resistant strains of
Enterococcus
,
Streptococcus
, and coagulase-negative staphylococci, except for
Eikenella corrodens
(MIC
90
, ≤4 μg/ml). GAR-936 was also very active against all anaerobic species, including tetracycline-, doxycycline-, and minocycline-resistant strains of
Prevotella
spp.,
Porphyromonas
spp.,
Bacteroides tectum
, and
Peptostreptococcus
spp., with an MIC
90
of ≤0.25 μg/ml. Erythromycin- and moxifloxacin-resistant fusobacteria were susceptible to GAR-936, with an MIC
90
of 0.06 μg/ml.
In Vitro Activities of Sitafloxacin (DU-6859a) and Six Other Fluoroquinolones against 8,796 Clinical Bacterial Isolates
Authors: Milatovic Dana , Schmitz Franz-Josef , Brisse Sylvain , Verhoef Jan , Fluit Ad C. 
Published: July 2002

ABSTRACT

The in vitro activities of sitafloxacin, ciprofloxacin, trovafloxacin, levofloxacin, clinafloxacin, gatifloxacin, and moxifloxacin against 5,046 gram-negative bacteria, 3,344 gram-positive cocci, and 406 anaerobes were determined. Sitafloxacin was the most active agent against gram-positive cocci and anaerobes. Against
Enterobacteriaceae
and nonfermenters, its activity was either equivalent to or better than that of clinafloxacin.
Correlation between Pretreatment Levels of Interferon Response Genes and Clinical Responses to an Immune Response Modifier (Imiquimod) in Genital Warts
Authors: Arany I. , Tyring S. K. , Brysk M. M. , Stanley M. A. , Tomai M. A. , Miller R. L. , Smith M. H. , McDermott D. J. , Slade H. B. 
Published: July 2002

ABSTRACTImiquimod (IQ) has been successfully used in treatment of genital warts. In clinical settings, patients responded well but wart reduction rates varied. Our aim was to find a correlation between clinical responses and pretreatment (constitutive) levels of genes that might be involved in the molecular action of IQ. Since IQ is a cytokine inducer, we analyzed levels of expression of genes of the JAK/STAT signaling pathway and their inhibitors as well as interferon response factors (IRFs) in pretreatment biopsy specimens from complete responders (99 to 100% wart reduction rate) versus incomplete responders (75 to 92% wart reduction rate) by reverse transcription-PCR. We found that mRNA levels of signal transducer and activator of transcription 1 (STAT1) and IRF1 were higher in complete responders than in incomplete responders. Incomplete responders expressed larger amounts of STAT3, IRF2, and protein inhibitor of activated STAT1 (PIAS1) mRNAs compared to complete responders before IQ treatment. We hypothesize that high-level expression of STAT1 and IRF1 is advantageous for a better IQ response. The observed differences in constitutive mRNA levels of these genes may be the consequence of alterations in cellular differentiation and/or variable expression of endogenous interferons. Previous in vitro studies showed that keratinocyte differentiation coordinates the balance between positive and negative signals along the JAK/STAT pathway by regulating the IRF1:IRF2 and STAT1:PIAS1 ratios and thus affecting induction of IQ-inducible genes. Specifically, differentiation supports constitutive expression of STAT1 and IRF1 mRNAs but not expression of IRF2 and PIAS1. Our data are in good agreement with studies that showed the importance of STAT1 in cytokine induction and activation of interferon-responsive genes by IQ.
Mechanism of Metronidazole Resistance in
Helicobacter pylori
: Comparison of the
rdxA
Gene Sequences in 30 Strains
Authors: Solcà Nadia Maggi , Bernasconi Marco Valerio , Piffaretti Jean-Claude 
Published: July 2002

ABSTRACT

The
rdxA
gene of 30 independently isolated
Helicobacter pylori
strains was sequenced. A comparison of the
rdxA
sequences revealed a higher percentage of amino acid substitutions in the corresponding protein than in other housekeeping genes. Out of 122 point mutations, 41 were missense and 4 were nonsense. A resistant strain with a nucleotide insertion in the
rdxA
sequence was also found. With the exception of the point mutations and the insertion generating a stop signal, no particular nucleotide mutation or amino acid substitution could be associated to metronidazole resistance. Moreover, phylogenetic analysis of the 30 nucleotide sequences did not demonstrate specific clusters associated with the resistance phenotype.
Regional Differences in Metronidazole Resistance and Increasing Clarithromycin Resistance among
Helicobacter pylori
Isolates from Japan
Authors: Kato Mototsugu , Yamaoka Yoshio , Kim Jae J. , Reddy Rita , Asaka Masahiro , Kashima Kei , Osato Michael S. , El-Zaatari Fouad A. K. , Graham David Y. , Kwon Dong H. 
Published: July 2002

ABSTRACT

The patterns of antibiotic resistance in
Helicobacter pylori
were assessed in two different regions in Japan. Overall, prevalences of resistance to metronidazole and clarithromycin were 12.4 and 12.9%, respectively. While there was no difference in clarithromycin resistance, the prevalence of metronidazole resistance was significantly higher in Kyoto (23.8%) than in Sapporo (8.1%). From 1996 to 1999, the prevalence of metronidazole resistance did not change but the prevalence of clarithromycin resistance doubled (from 9.1 to 18.7%).
Pharmacological Basis for Concentration-Controlled Therapy with Zidovudine, Lamivudine, and Indinavir
Authors: Kakuda Thomas N. , Page Linda M. , Anderson Peter L. , Henry Keith , Schacker Timothy W. , Rhame Frank S. , Acosta Edward P. , Brundage Richard C. , Fletcher Courtney V. 
Published: July 2002

ABSTRACTConventional antiretroviral therapy involves administration of standard fixed doses to adults and adolescents. This approach ignores interindividual variability in pharmacokinetics and results in substantial differences in systemic concentrations among patients. Thus, variability in systemic concentrations contributes to variability in response to therapy. This study was designed to evaluate the feasibility and safety of a regimen of zidovudine, lamivudine, and indinavir designed to achieve select target concentrations versus standard dose therapy. Twenty-four antiretroviral-naı̈ve subjects completed the 24-week study; 13 received standard therapy, and 11 received concentration-controlled therapy. There were no differences in baseline characteristics. Oral clearance for all three drugs was not different between weeks 2 and 28; average ratios of week 2 oral clearance to week 28 oral clearance were 0.95, 1.09, and 1.06 for zidovudine, lamivudine, and indinavir, respectively, with 95% confidence intervals including 1. The selected target concentrations were average steady-state concentrations of 0.19 mg/liter for zidovudine and 0.44 mg/liter for lamivudine and a trough concentration of 0.15 mg/liter for indinavir; mean concentrations achieved at week 28 in the concentration-controlled arm were 0.20, 0.54, and 0.19 mg/liter, respectively. Concentration-controlled therapy significantly reduced interpatient variability in zidovudine concentrations and significantly increased indinavir concentrations. There was no difference in adverse drug effects or adherence. This investigation has provided a pharmacologic basis for concentration-controlled therapy by demonstrating that it is feasible and has a safety profile no different from that of standard therapy. Additional studies to evaluate the virologic effect of the concentration-controlled approach to antiretroviral therapy are warranted.
Disruption of an
Enterococcus faecium
Species-Specific Gene, a Homologue of Acquired Macrolide Resistance Genes of Staphylococci, Is Associated with an Increase in Macrolide Susceptibility
Authors: Singh Kavindra V. , Malathum Kumthorn , Murray Barbara E. 
Published: July 2002

ABSTRACT

The complete sequence (1,479 nucleotides) of
msrC
, part of which was recently reported by others using a different strain, was determined. This gene was found in 233 of 233 isolates of
Enterococcus faecium
but in none of 265 other enterococci. Disruption of
msrC
was associated with a two- to eightfold decrease in MICs of erythromycin azithromycin, tylosin, and quinupristin, suggesting that it may explain in part the apparent greater intrinsic resistance to macrolides of isolates of
E. faecium
relative to many streptococci. This endogenous, species-specific gene of
E. faecium
is 53% identical to
msr
(A), suggesting that it may be a remote progenitor of the acquired macrolide resistance gene found in some isolates of staphylococci.
Family of Class 1 Integrons Related to In4 from Tn
1696
Authors: Partridge Sally R. , Recchia Gavin D. , Stokes H. W. , Hall Ruth M. 
Published: July 2002

ABSTRACT

The class 1 integron In28, found in the multidrug resistance transposon Tn
1403
, was found to be located in the
res
site of the backbone transposon and is flanked by a 5-bp direct duplication, indicating that it reached this position by transposition. In28 has a backbone structure related to that of In4, but has lost internal sequences, including the
sul1
gene, due to an IS
6100
-mediated deletion. In28 also lacks the partial copy of IS
6100
found in In4 and contains different gene cassettes,
blaP1, cmlA1,
and
aadA1
. In1, the class 1 integron found in the multidrug resistance plasmid R46, is also located in a putative
res
site and belongs to the In4 group. In1 has a shorter internal deletion than In28 and has also lost one end. Additional integrons with structures related to In4 were also found in databases, and most of them had also lost either one end or internal regions or both. Tn
610
belongs to this group.
Hypersusceptibility of thePseudomonas aeruginosa nfxBMutant to β-Lactams Due to Reduced Expression of the AmpC β-Lactamase
Authors: Masuda Nobuhisa , Sakagawa Eiko , Ohya Satoshi , Gotoh Naomasa , Nishino Takeshi 
Published: July 2002

ABSTRACTThePseudomonas aeruginosa nfxBmutant lackingmexAB-oprMshowed hypersusceptibility to 9 out of 24 β-lactams tested. This hypersusceptibility was found for thenfxBmutant lackingmexAB-oprM-mexXY(N108) but not for thenfxBmutant lacking bothmexAB-oprM-mexXYandampC. The level of the AmpC β-lactamase induction was reduced in N108. Thus, the reduced AmpC induction must be the cause of the hypersusceptibility.
Metallo-β-Lactamases in Clinical
Pseudomonas
Isolates in Taiwan and Identification of VIM-3, a Novel Variant of the VIM-2 Enzyme
Authors: Yan Jing-Jou , Hsueh Po-Ren , Ko Wen-Chien , Luh Kwen-Tay , Tsai Shu-Huei , Wu Hsiu-Mei , Wu Jiunn-Jong 
Published: July 2002

ABSTRACT

A total of 209 clinical isolates of
Pseudomonas
(193
Pseudomonas aeruginosa
, 10
P. putida
, 4
P. stutzeri
, and 2
P. fluorescens
isolates) with reduced susceptibilities to imipenem and/or ceftazidime were subjected to PCR assays with primers specific for
bla
IMP-1
,
bla
IMP-2
,
bla
VIM-1
, and
bla
VIM-2
and sequence analysis to identify the metallo-β-lactamases (MBLs) prevalent among these organisms in Taiwan; and 21 isolates gave positive results. Five isolates including two
P. putida
and three
P. stutzeri
isolates were found to carry
bla
IMP-1
, and six isolates including five
P. putida
and one
P. stutzeri
isolates harbored
bla
VIM-2
. The remaining 10 isolates were
P. aeruginosa
, and all were found to carry a novel variant of
bla
VIM-2
, designated
bla
VIM-3
. There are only two nucleotide differences between
bla
VIM-2
and
bla
VIM-3
, leading to two amino acid alterations. Our findings indicate that VIM-2 and its variant have become the most prevalent metalloenzymes in
Pseudomonas
in Taiwan. Southern hybridization with the
bla
VIM-2
-,
bla
VIM-3
-, and
bla
IMP-1
-specific probes revealed that only two VIM-2-producing
P. putida
isolates appeared to carry the MBL gene on plasmids. Pulsed-field gel electrophoresis showed that six VIM-3-producing
P. aeruginosa
isolates and two IMP-1-producing
P. stutzeri
isolates were genetically related, suggesting that the spread of these MBL genes in Taiwan could be due to clonal dissemination as well as genetic exchange between different clones.
Susceptibilities to Telithromycin and Six Other Agents and Prevalence of Macrolide Resistance Due to L4 Ribosomal Protein Mutation among 992 Pneumococci from 10 Central and Eastern European Countries
Authors: Nagai Kensuke , Appelbaum Peter C. , Davies Todd A. , Kelly Linda M. , Hoellman Dianne B. , Andrasevic Arjana Tambic , Drukalska Liga , Hryniewicz Waleria , Jacobs Michael R. , Kolman Jana , Miciuleviciene Jolanta , Pana Marina , Setchanova Lena , Thege Marianne Konkoly , Hupkova Helena , Trupl Jan , Urbaskova Pavla 
Published: July 2002

ABSTRACT

The macrolide and levofloxacin susceptibilities of 992 isolates of
Streptococcus pneumoniae
from clinical specimens collected in 1999 and 2000 were determined in 10 centers in Central and Eastern European countries. The prevalences of penicillin G-intermediate (MICs, 0.125 to 1 μg/ml) and penicillin-resistant (MICs, ≤2 μg/ml)
Streptococcus pneumoniae
isolates were 14.3 and 16.6%, respectively. The MICs at which 50% of isolates are inhibited (MIC
50
s) and the MIC
90
s of telithromycin were 0.016 and 0.06 μg/ml, respectively; those of erythromycin were 0.06 and >64 μg/ml, respectively; those of azithromycin were 0.125 and >64 μg/ml, respectively; those of clarithromycin were 0.03 and >64 μg/ml, respectively; and those of clindamycin were 0.06 and >64 μg/ml, respectively. Erythromycin resistance was found in 180
S. pneumoniae
isolates (18.1%); the highest prevalence of erythromycin-resistant
S. pneumoniae
was observed in Hungary (35.5%). Among erythromycin-resistant
S. pneumoniae
isolates, strains harboring
erm
(B) genes (125 strains [69.4%]) were found to be predominant over strains with
mef
(E) genes (25 strains [13.4%]), L4 protein mutations (28 strains [15.6%]), and
erm
(A) genes (2 strains [1.1%]). Similar pulsed-field gel electrophoresis patterns suggested that some strains containing L4 mutations from the Slovak Republic, Bulgaria, and Latvia were clonally related. Of nine strains highly resistant to levofloxacin (MICs, >8 μg/ml) six were isolated from Zagreb, Croatia. Telithromycin at ≤0.5 μg/ml was active against 99.8% of
S. pneumoniae
isolates tested and may be useful for the treatment of respiratory tract infections caused by macrolide-resistant
S. pneumoniae
isolates.
Characterization and Movement of the Class 1 Integron Known as Tn
2521
and Tn
1405
Authors: Partridge Sally R. , Brown Heidi J. , Hall Ruth M. 
Published: July 2002

ABSTRACT

Two putative transposons, Tn
2521
and Tn
1405
, carrying determinants for the PSE-4 β-lactamase and for resistance to streptomycin, spectinomycin, and sulfonamides were previously isolated from the chromosome of
Pseudomonas aeruginosa
Dalgleish. Detailed mapping and determination of the complete sequence of Tn
2521
revealed that it is a class 1 integron, here renamed In33, with a backbone structure identical to that of In4 from Tn
1696
. In33 contains two gene cassettes,
blaP1
and
aadA1
, replacing the
aacC1
-orfE-
aadA2
-
cmlA1
cassette array in In4. Although In33 does not include any transposition genes, movement of In33 (Tn
2521
) targeted to a single location in the IncP-1 plasmid R18-18 has been reported previously (M. I. Sinclair and B. W. Holloway, J. Bacteriol. 151:569-579, 1982). A 5-bp duplication of the target, which lies within the
res
site recognized by the ParA resolvase of R18-18, was present, indicating that the mechanism of movement was transposition. Together, these data indicate that class 1 integrons that are defective in self-transposition can move under appropriate circumstances. The Tn
1405
isolate studied was found to represent only the cassette array of In33, which had replaced the cassette array in the recipient plasmid R388, probably by homologous recombination.
Cloning, Expression, and Characterization of the
katG
Gene, Encoding Catalase-Peroxidase, from the Polycyclic Aromatic Hydrocarbon-Degrading Bacterium
Mycobacterium
sp. Strain PYR-1
Authors: Wang Rong-Fu , Wennerstrom David , Cao Wei-Wen , Khan Ashraf A. , Cerniglia Carl E. 
Published: July 2002

ABSTRACT

A 81-kDa protein from
Mycobacterium
sp. strain PYR-1 was expressed in response to exposure of the strain to the polycyclic aromatic hydrocarbon pyrene and recovered by two-dimensional gel electrophoresis. The N-terminal sequence of the protein indicated that it was similar to catalase-peroxidase. An oligonucleotide probe designed from this sequence was used to screen a genomic library of
Mycobacterium
sp. strain PYR-1, and a positive clone, containing a part of the gene encoding the 81-kDa protein, was isolated. A gene-walking technique was used to sequence the entire gene, which was identified as
katG
for catalase-peroxidase. The deduced KatG protein sequence showed significant homology to KatGII of
Mycobacterium fortuitum
and clustered with catalase-peroxidase proteins from other
Mycobacterium
species in a phylogenetic tree. The
katG
gene was expressed in
Escherichia coli
to produce a protein with catalase-peroxidase activity. Since the induction of this catalase-peroxidase occurred in pyrene-induced cultures and the exposure of these cultures to hydrogen peroxide reduced pyrene metabolism, our data suggest that this enzyme plays a role in polycyclic aromatic hydrocarbon metabolism by strain PYR-1.
Sulfate Reduction and Possible Aerobic Metabolism of the Sulfate-Reducing Bacterium
Desulfovibrio oxyclinae
in a Chemostat Coculture with
Marinobacter
sp. Strain MB under Exposure to Increasing Oxygen Concentrations
Authors: Sigalevich Pavel , Baev Mark V. , Teske Andreas , Cohen Yehuda 
Published: July 2002

ABSTRACT

A chemostat coculture of the sulfate-reducing bacterium
Desulfovibrio oxyclinae
together with a facultative aerobe heterotroph tentatively identified as
Marinobacter
sp. strain MB was grown under anaerobic conditions and then exposed to a stepwise-increasing oxygen influx (0 to 20% O
2
in the incoming gas phase). The coculture consumed oxygen efficiently, and no residual oxygen was detected with an oxygen supply of up to 5%. Sulfate reduction persisted at all levels of oxygen input, even at the maximal level, when residual oxygen in the growth vessel was 87 μM. The portion of
D. oxyclinae
cells in the coculture decreased gradually from 92% under anaerobic conditions to 27% under aeration. Both absolute cell numbers and viable cell counts of the organism were the same as or even higher than those observed in the absence of oxygen input. The patterns of consumption of electron donors and acceptors suggest that aerobic incomplete oxidation of lactate to acetate is performed by
D. oxyclinae
under high oxygen input. Both organisms were isolated from the same oxic zone of a cyanobacterial mat where they have to adapt to daily shifts from oxic to anoxic conditions. This type of syntrophic association may occur in natural habitats, enabling sulfate-reducing bacteria to cope with periodic exposure to oxygen.
Enzyme Diffusion from
Trichoderma atroviride
(=
T. harzianum
P1) to
Rhizoctonia solani
Is a Prerequisite for Triggering of
Trichoderma ech42
Gene Expression before Mycoparasitic Contact
Authors: Kullnig Cornelia , Mach Robert L. , Lorito Matteo , Kubicek Christian P. 
Published: July 2002

ABSTRACT

A plate confrontation experiment is commonly used to study the mechanism by which
Trichoderma
spp. antagonize and parasitize other fungi. Previous work with chitinase gene expression (
ech42
) during the precontact period of this process in which cellophane and dialysis membranes separated
Trichoderma harzianum
and its host
Rhizoctonia solani
resulted in essentially opposite results. Here, we show that cellophane membranes are permeable to proteins up to at least 90 kDa in size but that dialysis membranes are not.
ech42
was expressed during the precontact stage of the confrontation between
Trichoderma atroviride
and its host only if the cellophane was placed between the two fungi. These results are consistent with enzyme diffusion from
T. atroviride
to
R. solani
generating the trigger of
ech42
gene expression.
Use of Integrated Cell Culture-PCR To Evaluate the Effectiveness of Poliovirus Inactivation by Chlorine
Authors: Blackmer Felisa , Reynolds Kelly A. , Gerba Charles P. , Pepper Ian L. 
Published: July 2002

ABSTRACT
Current standards, based on cell culture assay, indicate that poliovirus is inactivated by 0.5 mg of free chlorine per liter after 2 min; however, integrated cell culture-PCR detected viruses for up to 8 min of exposure to the same chlorine concentration, requiring 10 min for complete inactivation. Thus, the contact time for chlorine disinfection of poliovirus is up to five times greater than previously thought.
Molecular Analysis of Surfactant-Driven Microbial Population Shifts in Hydrocarbon-Contaminated Soil
Authors: Colores Gregory M. , Macur Richard E. , Ward David M. , Inskeep William P. 
Published: July 2002

ABSTRACT

We analyzed the impact of surfactant addition on hydrocarbon mineralization kinetics and the associated population shifts of hydrocarbon-degrading microorganisms in soil. A mixture of radiolabeled hexadecane and phenanthrene was added to batch soil vessels. Witconol SN70 (a nonionic, alcohol ethoxylate) was added in concentrations that bracketed the critical micelle concentration (CMC) in soil (CMC′) (determined to be 13 mg g
−1
). Addition of the surfactant at a concentration below the CMC′ (2 mg g
−1
) did not affect the mineralization rates of either hydrocarbon. However, when surfactant was added at a concentration approaching the CMC′ (10 mg g
−1
), hexadecane mineralization was delayed and phenanthrene mineralization was completely inhibited. Addition of surfactant at concentrations above the CMC′ (40 mg g
−1
) completely inhibited mineralization of both phenanthrene and hexadecane. Denaturing gradient gel electrophoresis of 16S rRNA gene segments showed that hydrocarbon amendment stimulated
Rhodococcus
and
Nocardia
populations that were displaced by
Pseudomonas
and
Alcaligenes
populations at elevated surfactant levels. Parallel cultivation studies revealed that the
Rhodococcus
population can utilize hexadecane and that the
Pseudomonas
and
Alcaligenes
populations can utilize both Witconol SN70 and hexadecane for growth. The results suggest that surfactant applications necessary to achieve the CMC alter the microbial populations responsible for hydrocarbon mineralization.