bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comparative Antifungal Activities and Plasma Pharmacokinetics of Micafungin (FK463) against Disseminated Candidiasis and Invasive Pulmonary Aspergillosis in Persistently Neutropenic Rabbits
Authors: Petraitis Vidmantas , Petraitiene Ruta , Groll Andreas H. , Roussillon Kristin , Hemmings Melissa , Lyman Caron A. , Sein Tin , Bacher John , Bekersky Ihor , Walsh Thomas J. 
Published: July 2002

ABSTRACT

Micafungin (FK463) is an echinocandin that demonstrates potent in vitro antifungal activities against
Candida
and
Aspergillus
species. However, little is known about its comparative antifungal activities in persistently neutropenic hosts. We therefore investigated the plasma micafungin pharmacokinetics and antifungal activities of micafungin against experimental disseminated candidiasis and invasive pulmonary aspergillosis in persistently neutropenic rabbits. The groups with disseminated candidiasis studied consisted of untreated controls (UCs); rabbits treated with desoxycholate amphotericin B (DAMB) at 1 mg/kg of body weight/day; or rabbits treated with micafungin at 0.25, 0.5, 1, and 2 mg/kg/day intravenously. Compared with the UCs, rabbits treated with micafungin or DAMB showed significant dosage-dependent clearance of
Candida albicans
from the liver, spleen, kidney, brain, eye, lung, and vena cava. These in vivo findings correlated with the results of in vitro time-kill assays that demonstrated that micafungin has concentration-dependent fungicidal activity. The groups with invasive pulmonary aspergillosis studied consisted of UCs; rabbits treated with DAMB; rabbits treated with liposomal amphotericin B (LAMB) at 5 mg/kg/day; and rabbits treated with micafungin at 0.5, 1, and 2 mg/kg/day. In comparison to the significant micafungin dosage-dependent reduction of the residual burden (in log CFU per gram) of
C. albicans
in tissue, micafungin-treated rabbits with invasive pulmonary aspergillosis had no reduction in the concentration of
Aspergillus fumigatus
in tissue. DAMB and LAMB significantly reduced the burdens of
C. albicans
and
A. fumigatus
in tissues (
P
< 0.01). Persistent galactomannan antigenemia in micafungin-treated rabbits correlated with the presence of an elevated burden of
A. fumigatus
in pulmonary tissue. By comparison, DAMB- and LAMB-treated animals had significantly reduced circulating galactomannan antigen levels. Despite a lack of clearance of
A. fumigatus
from the lungs, there was a significant improvement in the rate of survival (
P
< 0.001) and a reduction in the level of pulmonary infarction (
P
< 0.05) in micafungin-treated rabbits. In summary, micafungin demonstrated concentration-dependent and dosage-dependent clearance of
C. albicans
from persistently neutropenic rabbits with disseminated candidiasis but not of
A. fumigatus
from persistently neutropenic rabbits with invasive pulmonary aspergillosis.
Lack of Pharmacokinetic Interaction between the Oral Anti-Influenza Prodrug Oseltamivir and Aspirin
Authors: Oo Charles , Barrett Joanne , Dorr Albert , Liu Baolian , Ward Penelope 
Published: July 2002

ABSTRACT
Twelve volunteers completed a two-sequence, three-way crossover study of a single 900-mg aspirin dose and multiple doses of 75 mg of oseltamivir in the absence and presence of 900 mg of aspirin. The plasma and urine results demonstrated no pharmacokinetic interaction between oseltamivir and aspirin.
Attachment of
Escherichia coli
O157:H7 to the Surfaces and Internal Structures of Apples as Detected by Confocal Scanning Laser Microscopy
Authors: Burnett Scott L. , Chen Jinru , Beuchat Larry R. 
Published: July 2002

ABSTRACT

Confocal scanning laser microscopy (CSLM) was used to demonstrate the attachment of
Escherichia coli
O157:H7 transformed with a plasmid encoding for green fluorescent protein (GFP) to the surface and within the internal structures of nonwaxed Red Delicious cv. apples. Apples at 2 or 25°C were inoculated with an
E. coli
O157:H7 cell suspension at 2 or 25°C. The effect of a negative temperature differential (cold inoculum, warm apple), a positive differential (warm inoculum, cold apple), and no differential (warm inoculum, warm apple), in combination with a pressure differential (atmospheric versus 10,130 Pa), on the attachment and infiltration of cells was determined. CSLM stereo images of external surfaces of apples subjected to all combinations of test parameters showed preferential cellular attachment to discontinuities in the waxy cuticle on the surface and to damaged tissue surrounding puncture wounds, where the pathogen was observed at depths up to 70 μm below the skin surface. Attachment to lenticels was sporadic but was occasionally observed at depths of up to 40 μm. Infiltration through the floral tube and attachment to seeds, cartilaginous pericarp, and internal trichomes were observed in all apples examined, regardless of temperature differential during inoculation. The pressure differential had no effect on infiltration or attachment of
E. coli
O157:H7. Image analysis to count cells at various depths within tissues was used to quantitatively compare the extent of infiltration into various apple structures as well as the effects of the temperature differential. Puncture wounds harbored greater numbers of the pathogen at greater depths than did other sites examined. Attachment or infiltration of cells was greater on the intact skin and in lenticels, russet areas, and the floral tube of apples inoculated under a negative temperature differential compared to those inoculated under no temperature differential. The results suggest that
E. coli
O157:H7 attached to internal core structures or within tissues of apples may evade decontamination treatments. Interventions designed to deliver disinfectants to these locations or to remove viable cells of
E. coli
O157:H7 and other pathogens from apples by other means need to be developed and validated.
Effects of Agronomic Treatments on Structure and Function of Ammonia-Oxidizing Communities
Authors: Phillips Carol J. , Harris Dave , Dollhopf Sherry L. , Gross Katherine L. , Prosser James I. , Paul Eldor A. 
Published: July 2002

ABSTRACT

The aim of this study was to determine the effects of different agricultural treatments and plant communities on the diversity of ammonia oxidizer populations in soil. Denaturing gradient gel electrophoresis (DGGE), coupled with specific oligonucleotide probing, was used to analyze 16S rRNA genes of ammonia oxidizers belonging to the β subgroup of the division
Proteobacteria
by use of DNA extracted from cultivated, successional, and native deciduous forest soils. Community profiles of the different soil types were compared with nitrification rates and most-probable-number (MPN) counts. Despite significant variation in measured nitrification rates among communities, there were no differences in the DGGE banding profiles of DNAs extracted from these soils. DGGE profiles of DNA extracted from samples of MPN incubations, cultivated at a range of ammonia concentrations, showed the presence of bands not amplified from directly extracted DNA.
Nitrosomonas
-like bands were seen in the MPN DNA but were not detected in the DNA extracted directly from soils. These bands were detected in some samples taken from MPN incubations carried out with medium containing 1,000 μg of NH
4
+
-N ml
−1
, to the exclusion of bands detected in the native DNA. Cell concentrations of ammonia oxidizers determined by MPN counts were between 10- and 100-fold lower than those determined by competitive PCR (cPCR). Although no differences were seen in ammonia oxidizer MPN counts from the different soil treatments, cPCR revealed higher numbers in fertilized soils. The use of a combination of traditional and molecular methods to investigate the activities and compositions of ammonia oxidizers in soil demonstrates differences in fine-scale compositions among treatments that may be associated with changes in population size and function.
Molecular Characterization of Irish
Salmonella enterica
Serotype Typhimurium: Detection of Class I Integrons and Assessment of Genetic Relationships by DNA Amplification Fingerprinting
Authors: Daly M. , Buckley J. , Power E. , O'Hare C. , Cormican M. , Cryan B. , Wall P. G. , Fanning S. 
Published: July 2002

ABSTRACT

Salmonella enterica
is among the principal etiological agents of food-borne illness in humans. Increasing antimicrobial resistance in
S. enterica
is a cause for worldwide concern. There is concern at present in relation to the increasing incidence of human infection with antimicrobial agent-resistant strains of
S. enterica
serotype Typhimurium, in particular of phage type DT104. Integrons appear to play an important role in the dissemination of antimicrobial resistance genes in many
Enterobacteriaceae
including
S. enterica
. In this study the antimicrobial susceptibilities and phage types of 74 randomly collected strains of
S. enterica
serotype Typhimurium from the Cork region of southern Ireland, obtained from human, animal (clinical), and food sources, were determined. Each strain was examined for integrons and typed by DNA amplification fingerprinting (DAF). Phage type DT104 predominated (
n
= 48). Phage types DT104b (
n
= 3), -193 (
n
= 9), -195 (
n
= 6), -208 (
n
= 3), -204a (
n
= 2), PT U302 (
n
= 1), and two nontypeable strains accounted for the remainder. All
S. enterica
serotype Typhimurium DT104 strains were resistant to ampicillin, chloramphenicol, streptomycin, Sulfonamide Duplex, and tetracycline, and one strain was additionally resistant to trimethoprim. All DT104 strains but one were of a uniform DAF type (designated DAF-I) and showed a uniform pattern of integrons (designated IP-I). The DT104b and PT U302 strains also exhibited the same resistance phenotype, and both had the DAF-I and IP-I patterns. The DAF-I pattern was also observed in a single DT193 strain in which no integrons were detectable. Greater diversity of antibiograms and DAF and IP patterns among non-DT104 phage types was observed. These data indicate a remarkable degree of homogeneity at a molecular level among contemporary isolates of
S. enterica
serotype Typhimurium DT104 from animal, human, and food sources in this region.
Characterization of Fungal Biofilms within a Municipal Water Distribution System
Authors: Doggett M. Steven 
Published: July 2002

ABSTRACT

Biofilms of a municipal water distribution system were characterized to assess the occurrence of fungi within surface matrixes. Densities of filamentous fungi ranged from 4.0 to 25.2 CFU cm
−2
, whereas yeast densities ranged from 0 to 8.9 CFU cm
−2
. Observations by scanning electron microscopy further suggested that spores, not hyphae or vegetative cells, comprised the primary source of viable propagules.
Role of

tfdC
I
D
I
E
I
F
I

and

tfdD
II
C
II
E
II
F
II

Gene Modules in Catabolism of 3-Chlorobenzoate by
Ralstonia eutropha
JMP134(pJP4)
Authors: Pérez-Pantoja D. , Guzmán L. , Manzano M. , Pieper D. H. , González B. 
Published: July 2002

ABSTRACT

The enzymes chlorocatechol-1,2-dioxygenase, chloromuconate cycloisomerase, dienelactone hydrolase, and maleylacetate reductase allow
Ralstonia eutropha
JMP134(pJP4) to degrade chlorocatechols formed during growth in 2,4-dichlorophenoxyacetate or 3-chlorobenzoate (3-CB). There are two gene modules located in plasmid pJP4,

tfdC
I
D
I
E
I
F
I

(module I) and

tfdD
II
C
II
E
II
F
II

(module II), putatively encoding these enzymes. To assess the role of both
tfd
modules in the degradation of chloroaromatics, each module was cloned into the medium-copy-number plasmid vector pBBR1MCS-2 under the control of the
tfd
R regulatory gene. These constructs were introduced into
R. eutropha
JMP222 (a JMP134 derivative lacking pJP4) and
Pseudomonas putida
KT2442, two strains able to transform 3-CB into chlorocatechols. Specific activities in cell extracts of chlorocatechol-1,2-dioxygenase (
tfdC
), chloromuconate cycloisomerase (
tfdD
), and dienelactone hydrolase (
tfdE
) were 2 to 50 times higher for microorganisms containing module I compared to those containing module II. In contrast, a significantly (50-fold) higher activity of maleylacetate reductase (
tfdF
) was observed in cell extracts of microorganisms containing module II compared to module I. The
R. eutropha
JMP222 derivative containing

tfdR-tfdC
I
D
I
E
I
F
I

grew four times faster in liquid cultures with 3-CB as a sole carbon and energy source than in cultures containing

tfdR-tfdD
II
C
II
E
II
F
II

. In the case of
P. putida
KT2442, only the derivative containing module I was able to grow in liquid cultures of 3-CB. These results indicate that efficient degradation of 3-CB by
R. eutropha
JMP134(pJP4) requires the two
tfd
modules such that TfdCDE is likely supplied primarily by module I, while TfdF is likely supplied by module II.
Development and Evaluation of a Model Predicting the Survival of
Escherichia coli
O157:H7 NCTC 12900 in Homemade Eggplant Salad at Various Temperatures, pHs, and Oregano Essential Oil Concentrations
Authors: Skandamis Panagiotis N. , Nychas George-John E. 
Published: July 2002

ABSTRACT

Homemade eggplant salad, a traditional Greek appetizer, was inoculated with
Escherichia coli
O157:H7 NCTC 12900 supplemented with different concentrations of oregano essential oil (0.0, 0.7, 1.4, and 2.1% [vol/wt]) and stored at different temperatures (0, 5, 10, and 15°C). The product's pH was adjusted to 4.0, 4.5, or 5.0 with lemon juice. For each combination of the environmental factors, the bacterial counts were modeled, using the Baranyi model, as a function of time to estimate the kinetic parameters of the pathogen. A reduction of more than 1 log unit in
E. coli
O157:H7 counts was observed in all cases, and the death rate depended on the pH, the storage temperature, and the essential oil concentration. Separate quadratic models were developed with natural logarithms of the shoulder period and death rate as estimated by the growth model, as a function of temperature, pH, and oregano essential oil concentrations. These were further used to predict the population of
E. coli
O157:H7 NCTC 12900 from other inoculated eggplant salads at random conditions of temperature, pH, and oregano oil concentration. The predicted values were compared with viable-count measurements for validation.
Fecal Shedding ofCampylobacterandArcobacterspp. in Dairy Cattle
Authors: Wesley I. V. , Wells S. J. , Harmon K. M. , Green A. , Schroeder-Tucker L. , Glover M. , Siddique I. 
Published: July 2002

ABSTRACTCampylobacter jejuni,Campylobacter coli, andArcobacterspp. were detected in feces of healthy dairy cows by highly specific multiplex-PCR assays. ForC. jejuni, at this one-time sampling, cows from 80.6% of farm operations (n= 31) and 37.7% of individual dairy cattle fecal samples (n= 2,085) were positive. Farm management factors were correlated with prevalence in herds in which >25% of cows were positive forC. jejuni. Statistical significance was set at aPof 0.20. Using these criteria, application of manure with broadcast spreaders (P= 0.17), feeding of whole cottonseed or hulls (P= 0.17) or alfalfa (P= 0.15), and accessibility of feed to birds (P= 0.17) were identified as possible risk factors forC. jejuniinfection.C. coliwas detected in at least one animal in 19.4% of operations and 1.8% of individual cows (n= 2,085). At the herd level, use of broadcaster spreaders was not a risk factor forC. coliinfection. ForArcobacter, cows from 71% of dairy operations (n= 31) and 14.3% of individual dairy cattle fecal samples (n= 1,682) were positive. At the herd level, forArcobacterspp., feeding of alfalfa (P= 0.11) and use of individual waterers (P= 0.19) were protective. This is the first description ofArcobacterspp. in clinically healthy dairy cattle and the first attempt to correlate their presence withC. jejuni.
Isolation and Expression of Lactate Dehydrogenase Genes fromRhizopus oryzae
Authors: Skory Christopher D. 
Published: July 2002

ABSTRACTRhizopus oryzaeis used for industrial production of lactic acid, yet little is known about the genetics of this fungus. In this study I cloned two genes,ldhAandldhB, which code for NAD+-dependentl-lactate dehydrogenases (LDH) (EC1.1.1.27), from a lactic acid-producing strain ofR. oryzae. These genes are similar to each other and exhibit more than 90% nucleotide sequence identity and they contain no introns. This is the first description ofldhgenes in a fungus, and sequence comparisons revealed that these genes are distinct from previously isolated prokaryotic and eukaryoticldhgenes. Protein sequencing of the LDH isolated fromR. oryzaeduring lactic acid production confirmed thatldhAcodes for a 36-kDa protein that converts pyruvate to lactate. Production of LdhA was greatest when glucose was the carbon source, followed by xylose and trehalose; all of these sugars could be fermented to lactic acid. Transcripts fromldhBwere not detected whenR. oryzaewas grown on any of these sugars but were present whenR. oryzaewas grown on glycerol, ethanol, and lactate. I hypothesize thatldhBencodes a second NAD+-dependent LDH that is capable of convertingl-lactate to pyruvate and is produced by cultures grown on these nonfermentable substrates. BothldhAandldhBrestored fermentative growth toEscherichia coli(ldhA pfl) mutants so that they grew anaerobically and produced lactic acid.
Characterization of Metabolites during Biodegradation of Hexahydro-1,3,5-Trinitro-1,3,5-Triazine (RDX) with Municipal Anaerobic Sludge
Authors: Hawari Jalal , Halasz Annamaria , Sheremata Tamara , Beaudet Sylvie , Groom Carl , Paquet Louise , Rhofir Chakib , Ampleman Guy , Thiboutot Sonia 
Published: July 2002

ABSTRACT

The biodegradation of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) in liquid cultures with municipal anaerobic sludge showed that at least two degradation routes were involved in the disappearance of the cyclic nitramine. In one route, RDX was reduced to give the familiar nitroso derivatives hexahydro-1-nitroso-3,5-dinitro-1,3,5-triazine (MNX) and hexahydro-1,3-dinitroso-5-nitro-1,3,5-triazine (DNX). In the second route, two novel metabolites, methylenedinitramine [(O
2
NNH)
2
CH
2
] and bis(hydroxymethyl)nitramine [(HOCH
2
)
2
NNO
2
], formed and were presumed to be ring cleavage products produced by enzymatic hydrolysis of the inner C—N bonds of RDX. None of the above metabolites accumulated in the system, and they disappeared to produce nitrous oxide (N
2
O) as a nitrogen-containing end product and formaldehyde (HCHO), methanol (MeOH), and formic acid (HCOOH) that in turn disappeared to produce CH
4
and CO
2
as carbon-containing end products.
Fermentation of Fructooligosaccharides by Lactic Acid Bacteria and Bifidobacteria
Authors: Kaplan Handan , Hutkins Robert W. 
Published: July 2002

ABSTRACT

Lactic acid bacteria and bifidobacteria were screened of their ability to ferment fructooligosaccharides (FOS) on MRS agar. Of 28 strains of lactic acid bacteria and bifidobacteria examined, 12 of 16
Lactobacillus
strains and 7 of 8
Bifidobacterium
strains fermented FOS. Only strains that gave a positive reaction by the agar method reached high cell densities in broth containing FOS.
Isolation and Characterization of Diverse Halobenzoate-Degrading Denitrifying Bacteria from Soils and Sediments
Authors: Song Bongkeun , Palleroni Norberto J. , Häggblom Max M. 
Published: July 2002

ABSTRACTDenitrifying bacteria capable of degrading halobenzoates were isolated from various geographical and ecological sites. The strains were isolated after initial enrichment on one of the monofluoro-, monochloro-, or monobromo-benzoate isomers with nitrate as an electron acceptor, yielding a total of 33 strains isolated from the different halobenzoate-utilizing enrichment cultures. Each isolate could grow on the selected halobenzoate with nitrate as the terminal electron acceptor. The isolates obtained on 2-fluorobenzoate could use 2-fluorobenzoate under both aerobic and denitrifying conditions, but did not degrade other halobenzoates. In contrast, the 4-fluorobenzoate isolates degraded 4-fluorobenzoate under denitrifying conditions only, but utilized 2-fluorobenzoate under both aerobic and denitrifying conditions. The strains isolated on either 3-chlorobenzoate or 3-bromobenzoate could use 3-chlorobenzoate, 3-bromobenzoate, and 2- and 4-fluorobenzoates under denitrifying conditions. The isolates were identified and classified on the basis of 16S rRNA gene sequence analysis and their cellular fatty acid profiles. They were placed in nine genera belonging to either the α-, β-, or γ-branch of theProteobacteria, namely,Acidovorax,Azoarcus,Bradyrhizobium,Ochrobactrum,Paracoccus,Pseudomonas,Mesorhizobium,Ensifer, andThauera. These results indicate that the ability to utilize different halobenzoates under denitrifying conditions is ubiquitously distributed in theProteobacteriaand that these bacteria are widely distributed in soils and sediments.
Development and Characterization of Diamondback Moth Resistance to Transgenic Broccoli Expressing High Levels of Cry1C
Authors: Zhao Jian-Zhou , Collins Hilda L. , Tang Juliet D. , Cao Jun , Earle Elizabeth D. , Roush Richard T. , Herrero Salvador , Escriche Baltasar , Ferré Juan , Shelton Anthony M. 
Published: July 2002

ABSTRACT

A field-collected colony of the diamondback moth,
Plutella xylostella
, had 31-fold resistance to Cry1C protoxin of
Bacillus thuringiensis
. After 24 generations of selection with Cry1C protoxin and transgenic broccoli expressing a Cry1C protein, the resistance that developed was high enough that neonates of the resistant strain could complete their entire life cycle on transgenic broccoli expressing high levels of Cry1C. After 26 generations of selection, the resistance ratios of this strain to Cry1C protoxin were 12,400- and 63,100-fold, respectively, for the neonates and second instars by a leaf dip assay. The resistance remained stable until generation 38 (G38) under continuous selection but decreased to 235-fold at G38 when selection ceased at G28. The Cry1C resistance in this strain was seen to be inherited as an autosomal and incompletely recessive factor or factors when evaluated using a leaf dip assay and recessive when evaluated using Cry1C transgenic broccoli. Saturable binding of
125
I-Cry1C was found with brush border membrane vesicles (BBMV) from both susceptible and Cry1C-resistant strains. Significant differences in Cry1C binding to BBMV from the two strains were detected. BBMV from the resistant strain had about sevenfold-lower affinity for Cry1C and threefold-higher binding site concentration than BBMV from the susceptible strain. The overall Cry1C binding affinity was just 2.5-fold higher for BBMV from the susceptible strain than it was for BBMV from the resistant strain. These results suggest that reduced binding is not the major mechanism of resistance to Cry1C.
Biotransformation of the Antimelanoma Agent Betulinic Acid by
Bacillus megaterium
ATCC 13368
Authors: Chatterjee Parnali , Kouzi Samir A. , Pezzuto John M. , Hamann Mark T. 
Published: July 2002

ABSTRACT

Microbial transformation of the antimelanoma agent betulinic acid was studied. The main objective of this study was to utilize microorganisms as in vitro models to predict and prepare potential mammalian metabolites of this compound. Preparative-scale biotransformation with resting-cell suspensions of
Bacillus megaterium
ATCC 13368 resulted in the production of four metabolites, which were identified as 3-oxo-lup-20(29)-en-28-oic acid, 3-oxo-11α-hydroxy-lup-20(29)-en-28-oic acid, 1β-hydroxy-3-oxo-lup-20(29)-en-28-oic acid, and 3β,7β,15α-trihydroxy-lup-20(29)-en-28-oic acid based on nuclear magnetic resonance and high-resolution mass spectral analyses. In addition, the antimelanoma activities of these metabolites were evaluated with two human melanoma cell lines, Mel-1 (lymph node) and Mel-2 (pleural fluid).