bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation of the VITEK 2 System for Rapid Direct Identification and Susceptibility Testing of Gram-Negative Bacilli from Positive Blood Cultures
Authors: Ling Thomas K. W. , Liu Z. K. , Cheng Augustine F. B.
Published: October 2003

This study explores the possibility of combining the BacT/Alert Microbial Detection System with the VITEK 2 system to achieve rapid bacterial identification and susceptibility testing. Direct inoculation of bacterial suspension to the VITEK 2 ID-GNB card and AST-NO09 card was made by differential centrifugation of blood cultures of organisms with gram-negative enteric bacillus-like morphology. A total of 118 strains were investigated; of these, 97 (82.2%) strains were correctly identified to the species level and 21 (17.8%) strains were not identified; by comparing the results with those of the reference method of API identification systems using a pure culture, it was found that no strain had been misidentified. Among the 21 strains with no identification, 13 (61.9%) strains were nonfermenters. The direct-identification reporting time of VITEK 2 was 3.3 h. Direct testing of susceptibility to 11 antibiotics, i.e., amikacin, cefepime, ceftazidime, ciprofloxacin, gentamicin, imipenem, meropenem, netilmicin, piperacillin, piperacillin-tazobactam, and tobramycin, was also performed by using the broth microdilution (MB) method according to the NCCLS guidelines as a reference. After comparing the MICs of the VITEK 2 system with those obtained by the MB method within ±twofold dilution, it was determined that the 1,067 organism-antibiotic combinations had an overall correct rate of 97.6% (1,041 combinations). The rates of susceptibility to the 11 antibiotics ranged from 88.7 to 100%, respectively. Only two (0.2%) and four (0.4%) combinations of the susceptibility tests gave very major errors (i.e., reported as sensitive by the VITEK 2 system but shown to be resistant by the MB method) and major errors (i.e., reported as resistant by the VITEK 2 system but shown to be sensitive by the MB method), respectively. The reporting time for the direct testing of susceptibility against the 11 antibiotics for 97 blood culture isolates by the VITEK 2 system ranged from 3.3 to 17.5 h. Compared with conventional methods that require 1 or 2 days, this method can make same-day reporting possible and thus permit better patient management.
Algorithm To Determine Cost Savings of Targeting Antimicrobial Therapy Based on Results of Rapid Diagnostic Testing
Authors: Oosterheert J. J. , Bonten M. J. M. , Buskens E. , Schneider M. M. E. , Hoepelman I. M.
Published: October 2003

A rapid diagnosis of pneumococcal pneumonia may allow the earlier use of narrow-spectrum antimicrobial therapy. It is unknown, however, whether rapid diagnostic testing of patients hospitalized with community-acquired pneumonia (CAP) admitted to hospital lowers costs. Therefore, an algorithm to calculate the costs associated with the diagnosis and treatment of CAP was formulated. Subsequently, the algorithm was applied to clinical data for 122 consecutively admitted patients with CAP whose sputum samples were Gram stained and whose urine was tested for
Streptococcus pneumoniae
antigen. The costs of initial antimicrobial therapy, personnel, and materials were measured. Compared to the most expensive empirical regimen, rapid diagnostic testing would result in cost savings per patient (PP) of €3.51 for Gram staining and €8.11 for urinary pneumococcal antigen testing (€1 is equal to US$1.13, from 2000 to 2002). Compared to the cheapest regimen, Gram staining would increase the cost by €2.25 PP, and urinary antigen testing would increase the cost by €24.26 PP. In our setting, the use of rapid diagnostic testing would not lower costs. Cost savings depend, however, on the differences in the prices of the different antibiotics chosen and the proportion of evaluable and positive samples.
Detection of Simulated Candidemia by the BACTEC 9240 System with Plus Aerobic/F and Anaerobic/F Blood Culture Bottles
Authors: Horvath Lynn L. , Hospenthal Duane R. , Murray Clinton K. , Dooley David P.
Published: October 2003

We studied the ability of the BACTEC 9240 automated blood culture system to detect simulated candidemia, including both
Candida albicans
and non-
albicans Candida
species. Simulated blood cultures were produced using 50
Candida
isolates and BACTEC Plus Aerobic/F and Anaerobic/F blood culture bottles. Ten milliliters of blood and a suspension of each isolate containing 1,000 CFU were introduced into each bottle and then incubated at 35°C in the BACTEC 9240 system. The system detected growth in 56 of 100 bottles. Four isolates did not have growth detected in either bottle after 21 days of incubation, resulting in four missed episodes of candidemia. If the blood culture bottles had been incubated for 5 days, an additional episode of candidemia would have remained undetected. If the bottles had been incubated for only 3 days, another episode would have been missed, resulting in up to six missed episodes of candidemia (four
Candida glabrata
isolates, one
C. albicans
isolate, and one
Candida rugosa
isolate). Terminal subculture of bottles without detected growth recovered yeast in 93% (41 of 44) of the bottles, representing 41 false negatives. In bottles where growth was detected, the time to detection was ∼24 h. However, the mean time to growth detection for
C. glabrata
isolates in anaerobic medium was 22.14 ± 2.47 h, but it was 120.89 ± 35.33 h in aerobic medium (
P
< 0.001). The BACTEC 9240 system detected growth of most
Candida
isolates; however, the delayed time to detection of
C. glabrata
is clinically significant. Given the high rate of false negatives, terminal subcultures may be helpful in certain situations.
Extended Epidemic of Nosocomial Urinary Tract Infections Caused by
Serratia marcescens
Authors: Su Lin-Hui , Ou Jonathan T. , Leu Hsieh-Shong , Chiang Ping-Cherng , Chiu Yueh-Pi , Chia Ju-Hsin , Kuo An-Jing , Chiu Cheng-Hsun , Chu Chishih , Wu Tsu-Lan , Sun Chien-Feng , Riley Thomas V. , Chang Barbara J.
Published: October 2003

In recent years a significant increase in the incidence of
Serratia marcescens
infections was noted at the Chang Gung Memorial Hospital, Taoyuan, Taiwan. A review of laboratory (1991 to 2002) and infection control (1995 to 2002) records showed the possibility of an extended epidemic of nosocomial urinary tract infections (UTIs) caused by
S. marcescens
. Therefore, in 1998 and 1999, 87 isolates were collected from patients with such infections and examined and another 51 isolates were collected in 2001 and 2002. The patients were mostly elderly or the infections were associated with the use of several invasive devices.
S. marcescens
was usually the only pathogen found in urine cultures in our study. Neither prior infections nor disseminated infections with the organism were observed in these patients. Resistance to most antibiotics except imipenem was noted. Two genotyping methods, pulsed-field gel electrophoresis and infrequent-restriction-site PCR, were used to examine the isolates. A total of 12 genotypes were identified, and 2 predominant genotypes were found in 72 (82.8%) of the 87 isolates derived from all over the hospital. However, 63.9% of the isolates of the two genotypes were from neurology wards. A subsequent intervention by infection control personnel reduced the infection rate greatly. The number and proportion of the two predominant genotypes were significantly reduced among the 51 isolates collected in 2001 and 2002. Thus, a chronic and long-lasting epidemic of nosocomial UTIs caused by
S. marcescens
was identified and a successful intervention was carried out. Both a cautious review of laboratory and infection control data and an efficient genotyping system are necessary to identify such a cryptic epidemic and further contribute to the quality of patient care.
Utility of Multilocus Sequence Typing as an Epidemiological Tool for Investigation of Outbreaks of Gastroenteritis Caused by
Campylobacter jejuni
Authors: Sails Andrew D. , Swaminathan Bala , Fields Patricia I.
Published: October 2003

Multilocus sequence typing (MLST) has been proven useful for the study of the global population structure of
Campylobacter jejuni
; however, its usefulness for the investigation of outbreaks of disease caused by
C. jejuni
has not been proven. In this study, MLST plus sequencing of the
flaA
short variable region (SVR) were applied to 47 isolates from 12 outbreaks of
C. jejuni
infection whose relatedness has been determined previously, and the results were compared to those of serotyping and pulsed-field gel electrophoresis (PFGE). Isolates implicated in an outbreak were indistinguishable by all four subtyping methods, with sporadic isolates being distinguished from outbreak isolates. Two sporadic isolates from one outbreak were resistant to
Sma
I digestion and therefore nontypeable by PFGE but were differentiated from the outbreak strain by the other methods. PFGE and
flaA
SVR typing were the most discriminatory methods, with discriminatory indices (DI) of 0.930 and 0.923, respectively. However, an epidemic strain from one outbreak was distinguished from the other outbreak isolates by
flaA
SVR typing; its
flaA
allele was different at five nucleotides, suggesting that this change was possibly mediated by recombination. MLST was less discriminatory than PFGE and
flaA
SVR typing (DI = 0.859), and many of the epidemic strains possessed common sequence types (STs) including ST-8, -21, -22, and -42. However, further discrimination within STs was achieved by
flaA
SVR typing or PFGE. The results from this study demonstrate that a combined approach of MLST plus
flaA
SVR typing provides a level of discrimination equivalent to PFGE for outbreak investigations.
Practical Disk Diffusion Method for Detection of Inducible Clindamycin Resistance in
Staphylococcus aureus
and Coagulase-Negative Staphylococci
Authors: Fiebelkorn K. R. , Crawford S. A. , McElmeel M. L. , Jorgensen J. H.
Published: October 2003

Resistance to macrolides in staphylococci may be due to active efflux (encoded by
msrA
) or ribosomal target modification (macrolide-lincosamide-streptogramin B [MLS
B
] resistance; usually encoded by
ermA
or
ermC
). MLS
B
resistance is either constitutive or inducible following exposure to a macrolide. Induction tests utilize closely approximated erythromycin and clindamycin disks; the flattening of the clindamycin zone adjacent to the erythromycin disk indicates inducible MLS
B
resistance. The present study reassessed the reliability of placing erythromycin and clindamycin disks in adjacent positions (26 to 28 mm apart) in a standard disk dispenser, compared to distances of 15 or 20 mm. A group of 130 clinical isolates of
Staphylococcus aureus
and 100 isolates of erythromycin-resistant coagulase-negative staphylococci (CNS) were examined by disk approximation; all CNS isolates and a subset of
S. aureus
isolates were examined by PCR for
ermA
,
ermC
, and
msrA
. Of 114 erythromycin-resistant
S. aureus
isolates, 39 demonstrated constitutive resistance to clindamycin, while 33 showed inducible resistance by disk approximation at all three distances. Only one isolate failed to clearly demonstrate induction at 26 mm. Of 82 erythromycin-resistant CNS isolates that contained
ermA
or
ermC
, 57 demonstrated constitutive clindamycin resistance, and 25 demonstrated inducible resistance, at 20 and 26 mm. None of the 42
S. aureus
isolates or 18 CNS isolates containing only
msrA
and none of the erythromycin-susceptible isolates yielded positive disk approximation tests. Simple placement of erythromycin and clindamycin disks at a distance achieved with a standard disk dispenser allowed detection of 97% of
S. aureus
strains and 100% of CNS strains with inducible MLS
B
resistance in this study.
Direct Susceptibility Testing of Positive Blood Cultures by Using Sensititre Broth Microdilution Plates
Authors: Chapin Kimberle C. , Musgnug Michael C.
Published: October 2003

Traditional susceptibility testing of blood cultures requires overnight incubation in order to obtain isolated colonies. Susceptibility results can be reported up to 24 h sooner by using a bacterial pellet from the blood culture broth. This study evaluated the accuracy of direct susceptibility testing from positive ESP blood culture broths by using Sensititre broth microdilution plates compared to testing with isolated colonies. Practical inclusion criteria were applied to gram-positive organisms to avoid reporting susceptibilities for probable contaminants. All gram-negative organisms were tested directly. An aliquot of the blood culture was centrifuged, and the resulting pellet was used to make a 0.5 McFarland suspension. Microdilution plates were inoculated and interpreted according to the manufacturer's instructions. Colony counts were performed to ensure proper colony density was achieved. A total of 199 patient and seeded blood cultures were evaluated for both essential (within ±1 twofold dilution) and categorical (sensitive, intermediate, or resistant) agreement. Testing of 93 gram-positive isolates (1,214 antimicrobial agent-organism combinations) yielded 98% essential agreement and categorical error rates of 0.3% minor, no major (false resistance), and 1.7% very major (false susceptibility) errors. For 106 gram-negative isolates (1,828 antimicrobial agent-organism combinations), the essential agreement was 99%. Categorical error rates were 0.5, 0, and 2.0% for minor, major, and very major errors, respectively. Performance was comparable for both gram-positive and gram-negative isolates, as well as for both aerobic and anaerobic media. Using this direct testing methodology, reliable susceptibility results can be reported to physicians 24 h sooner, allowing earlier appropriate modification of antimicrobial therapy.
Microwave Sterilization of Femoral Head Allograft
Authors: Dunsmuir Robert A. , Gallacher Grace
Published: October 2003

The potential shortage of allograft bone has led to the need to investigate other sources of bone for allografts. Some allograft bone donated from primary total hip arthroplasty recipients must be discarded or treated to become useable as a result of bacterial contamination. Femoral head allografts were contaminated withStaphylococcus aureusandBacillus subtilis. A domestic microwave oven was used. The contaminated bone was exposed to microwave irradiation for different time periods. The samples were then cultured to attempt to grow the two bacterial species. The contaminated bone samples failed to grow any organisms after 2 min of exposure to microwave irradiation. This study shows that sterilization of femoral head allografts contaminated withS. aureusandB. subtiliscan be achieved with microwave irradiation in a domestic microwave oven. This method of sterilization of bone allografts is cheap, easily used, and an effective way to process contaminated bone.
Use of Denaturing High-Performance Liquid Chromatography To Identify
Bacillus anthracis
by Analysis of the 16S-23S rRNA Interspacer Region and
gyrA
Gene
Authors: Hurtle William , Bode Elizabeth , Kaplan Rebecca Susan , Garrison Jeff , Kearney Brian , Shoemaker David , Henchal Erik , Norwood David
Published: October 2003

Denaturing high-performance liquid chromatography (DHPLC) was evaluated as a method for identifying
Bacillus anthracis
by analyzing two chromosomal targets, the 16S-23S intergenic spacer region (ISR) and the
gyrA
gene. The 16S-23S ISR was analyzed by this method with 42 strains of
B. anthracis
, 36 strains of
Bacillus cereus
, and 12 strains of
Bacillus thuringiensis
; the
gyrA
gene was analyzed by this method with 33 strains of
B. anthracis
, 27 strains of
B. cereus
, and 9 strains of
B. thuringiensis
. Two blind panels of 45 samples each were analyzed to evaluate the potential diagnostic capability of this method. Our results show that DHPLC is an efficient method for the identification of
B. anthracis
.
Exophiala oligospermaCausing Olecranon Bursitis
Authors: Bossler A. D. , Richter S. S. , Chavez A. J. , Vogelgesang S. A. , Sutton D. A. , Grooters A. M. , Rinaldi M. G. , de Hoog G. S. , Pfaller M. A
Published: October 2003

A 62-year-old male with a history of Wegener's granulomatosis and immunosuppressive therapy presented with chronic olecranon bursitis. A black velvety mould with brown septate hyphae and tapered annellides was isolated from a left elbow bursa aspirate and was identified as anExophialaspecies. Internal transcribed sequence rRNA sequencing showed the isolate to be identical toExophiala oligosperma. The patient was successfully treated with aspiration and intrabursal amphotericin B.
Rapid and Specific Detection of
Mycobacterium tuberculosis
by Using the Smart Cycler Instrument and a Specific Fluorogenic Probe
Authors: Cleary Timothy J. , Roudel Gladys , Casillas Ofelia , Miller Nancimae
Published: October 2003

A procedure using the Smart Cycler instrument and a fluorescence quencher (FQ) probe for the specific identification of
Mycobacterium tuberculosis
complex (MTB) was used to detect organisms in 366 acid-fast bacillus smear-positive respiratory specimens. It was compared to culture and the AMPLICOR
M
.
tuberculosis
PCR test. MTB was isolated from 198 of these samples. The FQ PCR assay was sensitive (197 of 198, 99.5%) and specific (165 of 168, 98.2%); no significant difference was observed between the two PCR protocols. After DNA extraction, a final result was available within 1.5 h with the real-time PCR protocol.
Differentiation of
Candida dubliniensis
from
Candida albicans
on Pal's Agar
Authors: Al Mosaid Asmaa , Sullivan Derek J. , Coleman David C.
Published: October 2003

Production of a hyphal fringe around colonies grown on Pal's agar (sunflower seed agar) at 30°C for 48 to 72 h provides a simple means of discriminating between isolates of
C. dubliniensis
and
C. albicans
with 100% accuracy. Of 128
C. dubliniensis
isolates tested on this medium, all produced a hyphal fringe. In contrast, none of the 124
C. albicans
isolates tested produced a hyphal fringe. Pal's medium has the added advantage of being prepared from inexpensive, readily available seeds.
Assessment of Immunoglobulin M Enzyme Immunoassays for Diagnosis of Measles
Authors: Tipples Graham A. , Hamkar Rasool , Mohktari-Azad Talat , Gray Michael , Parkyn Geoff , Head Carol , Ratnam Samuel
Published: October 2003

We evaluated the performance of three commercial measles immunoglobulin M enzyme immunoassays from Meddens, Denka Seiken, and Behring. The sensitivities were determined to be 96.7% for the Meddens and Denka Seiken assays and 87.9% for the Behring assay. The specificities of the assays were determined to be 94.6% for Meddens, 98.2% for Denka Seiken, and 98.7% for Behring.
Use of Hepatitis B Virus DNA Quantitation To Predict Hepatitis B e Antigen Reversion in Cases of Chronic Hepatitis B
Authors: Chan Henry Lik-Yuen , Wong May Ling , Hui Alex Yui , Hung Lawrence Cheung-Tsui , Chan Francis Ka-Leung , Sung Joseph Jao-Yiu
Published: October 2003

Seventy-three chronic hepatitis B patients who had either hepatitis B e antigen (HBeAg) seroconversion (group I) or HBeAg-negative disease (group II) were studied. HBV DNA levels at HBeAg seroconversion (group I) and at initial visits (group II) were significantly lower among patients who were persistently negative for HBeAg than among those who underwent HBeAg reversion.
Genetic Diversity among Clinical Isolates of
Candida glabrata
Analyzed by Randomly Amplified Polymorphic DNA and Multilocus Enzyme Electrophoresis Analyses
Authors: Boldo Xavier M. , Villa-Tanaca Lourdes , Zúñiga Gerardo , Hernández-Rodríguez César
Published: October 2003

The genetic diversity of 47 clinical and reference strains of
Candida glabrata
from several geographical origins and diverse clinical disorders, with different antifungal susceptibilities, as well as their genetic relationships were studied through multilocus enzyme electrophoresis (MLEE) and randomly amplified polymorphic DNA (RAPD) techniques. The genetic diversity estimated for 11 MLEE loci measured as average heterozygosity (
h
) was 0.055. A high level of genetic relatedness among isolates was established by cluster analysis. Forty-nine RAPD markers were analyzed, and the average genetic diversity among isolates, estimated by Shannon's index (

H
o

), was 0.372. The Φ
ST
values estimated through an analysis of molecular variance to assess genetic differentiation among isolates revealed no genetic differentiation among them. Our results revealed very low genetic diversity among isolates, a lack of differentiation, and no association with their geographic origin and the clinical characteristics.
Comparison of PCR Assay to Culture for Surveillance Detection of Vancomycin-Resistant Enterococci
Authors: Paule Suzanne M. , Trick William E. , Tenover Fred C. , Lankford Mary , Cunningham Susan , Stosor Valentina , Cordell Ralph L. , Peterson Lance R.
Published: October 2003

Direct multiplex PCR assay using
vanA
and
vanB
primers, which provides rapid results, was more sensitive than culture on selective media for samples collected by rectal swab (20 of 46 versus 8 of 46;
P
< 0.001) or perianal swab (17 of 58 versus 12 of 58;
P
= 0.059) for the detection of gastrointestinal colonization by vancomycin-resistant enterococci.
Cellular Fatty Acid Profile Distinguishes
Burkholderia pseudomallei
from Avirulent
Burkholderia thailandensis
Authors: Inglis Timothy J. J. , Aravena-Roman Max , Ching Simon , Croft Kevin , Wuthiekanun V. , Mee Brian J.
Published: October 2003

Burkholderia pseudomallei
, the cause of melioidosis, can be distinguished from the closely related but nonpathogenic
Burkholderia thailandensis
by gas chromatography (GC) analysis of fatty acid derivatives. A 2-hydroxymyristic acid derivative (14:0 2OH) was present in 95% of
B. pseudomallei
isolates and no
B. thailandensis
isolates. GC mass spectrophotometry confirmed that 2-hydroxymyristic acid was present in
B. pseudomallei
. GC-fatty acid methyl ester analysis may be useful in distinguishing these two closely related species.
Comparison of In Vitro Activities of 17 Antifungal Drugs against a Panel of 20 Dermatophytes by Using a Microdilution Assay
Authors: Favre Bertrand , Hofbauer Bettina , Hildering Kwang-Soo , Ryder Neil S.
Published: October 2003

The in vitro activities of 17 antifungal drugs against a panel of 20 dermatophytes comprising 6 different species were determined using a microdilution assay according to the NCCLS M38-P method with some modifications. Terbinafine was the most potent systemic drug while tolnaftate and amorolfine were the most active topical agents.
Amplified-Fragment Length Polymorphism as a Complement to IS
6110
-Based Restriction Fragment Length Polymorphism Analysis for Molecular Typing of
Mycobacterium tuberculosis
Authors: Ruiz Monserrat , Rodríguez Juan Carlos , Rodríguez-Valera Francisco , Royo Gloria
Published: October 2003

The amplified-fragment length polymorphism (AFLP) technique was applied to clusters of
Mycobacterium tuberculosis
clinical isolates obtained by using IS
6110
-based restriction fragment length polymorphism (RFLP). Ten of the RFLP clusters showed identical AFLP patterns also, but the other 13 could be resolved into subclusters by AFLP. Our results suggest that some RFLP clusters may not be due to recent transmission and that AFLP may be a useful complementary technique.
Diagnosis of Congenital Toxoplasmosis
Authors: Filisetti Denis , Gorcii Mohamed , Pernot-Marino Elodie , Villard Odile , Candolfi Ermanno
Published: October 2003

Three PCR targets (18S ribosomal DNA, B1, and AF146527) and mouse inoculation were compared for 83 samples in the context of congenital toxoplasmosis. These four techniques are not statistically different in terms of sensitivity and specificity. However, further analysis highlighted problems sometimes encountered with PCR diagnosis of congenital toxoplasmosis.
Use of Cefoperazone MacConkey Agar for Selective Isolation of
Laribacter hongkongensis
Authors: Lau Susanna K. P. , Woo Patrick C. Y. , Hui Wai-ting , Li Maria W. S. , Teng Jade L. L. , Que Tak-Lun , Luk Wei-Kwang , Lai Raymond W. M. , Yung Raymond W. H. , Yuen Kwok-yung
Published: October 2003

A new selective medium, cefoperazone MacConkey agar (CMA), was developed for primary isolation of
Laribacter hongkongensis
from stool. Its performance in quantitative recovery and in a clinical evaluation of 4,741 human diarrheal stool specimens was superior to that of charcoal cefoperazone deoxycholate agar. In addition, with CMA,
Arcobacter butzleri
was unexpectedly isolated from the stools of six patients.
Volume Effect on Sensitivity of Nucleic Acid Amplification Tests for Detection of
Chlamydia trachomatis
in Urine Specimens from Females
Authors: Moncada Jeanne , Chow Joan M. , Schachter Julius
Published: October 2003

Nucleic acid amplification tests (NAATs) for the detection of
Chlamydia trachomatis
are routinely used on first-catch urine (FCU) specimens. We analyzed data from a head-to-head comparison of NAATs on female FCU specimens and found that the volume of urine collected could affect test performance.
Differentiation ofMycoplasmaSpecies by 16S Ribosomal DNA PCR and Denaturing Gradient Gel Electrophoresis Fingerprinting
Authors: McAuliffe Laura , Ellis Richard J. , Ayling Roger D. , Nicholas Robin A. J.
Published: October 2003

Denaturing gradient gel electrophoresis (DGGE) of a 16S ribosomal DNA PCR product was used to differentiate 32 mycoplasma species of veterinary significance. Twenty-seven (85%) species could be differentiated by DGGE. This method could enable the rapid identification of many mycoplasma species for which there is no specific PCR available and which are currently identified by using culture and serological tests.
Biochemical Properties of a Newly Described
Escherichia
Species,
Escherichia albertii
Authors: Abbott Sharon L. , O'Connor Jennifer , Robin Tom , Zimmer Barbara L. , Janda J. Michael
Published: October 2003

Five strains of a newly described
Escherichia
species,
Escherichia albertii
, were extensively characterized by conventional biochemical methods and by commercial identification panels.
E. albertii
is an indole-negative species that ferments
d
-mannitol but not
d
-xylose. Because these strains are not included in the databases of commercial systems at present, they were most often identified as
Hafnia
,
Salmonella
,
Escherichia coli
, or, on one system (MicroScan dried overnight panels),
Yersinia ruckeri
.
High Disease Burden of Diarrhea Due to Enterotoxigenic
Escherichia coli
among Rural Egyptian Infants and Young Children
Authors: Rao Malla R. , Abu-Elyazeed Remon , Savarino Stephen J. , Naficy Abdollah B. , Wierzba Thomas F. , Abdel-Messih Ibrahim , Shaheen Hind , Frenck Robert W. , Svennerholm Ann-Mari , Clemens John D.
Published: October 2003

The incidence of enterotoxigenic
Escherichia coli
diarrhea among Egyptian children was 1.5 episodes per child per year and accounted for 66% of all first episodes of diarrhea after birth. The incidence increased from 1.7 episodes per child per year in the first 6 months of life to 2.3 in the second 6 months and declined thereafter.
Photographic and Luminometric Detection of Luciferase Reporter Phages for Drug Susceptibility Testing of Clinical
Mycobacterium tuberculosis
Isolates
Authors: Hazbón Manzour Hernando , Guarín Nora , Ferro Beatriz Eugenia , Rodríguez Ana Lucía , Labrada Luz Angela , Tovar Rafael , Riska Paul F. , Jacobs William R.
Published: October 2003

Luciferase reporter phages (LRPs) have proven to be efficient tools for drug susceptibility testing of
Mycobacterium tuberculosis
. Luminometric detection of LRP activity offers higher sensitivity and quantitative results, while a Polaroid film detection method offers a “low-tech” inexpensive alternative that is called the Bronx box. In this work we evaluated, improved, and compared the performance of the luminometer and the Bronx box formats for drug susceptibility testing with LRPs by using 51 clinical isolates of
M. tuberculosis
, with the agar proportion method (PM) serving as reference. The sensitivity in detecting resistance to isoniazid and rifampin, antibiotics that define multidrug resistance (MDR), was 100% for both methods. The turnaround time for results was reduced from 3 weeks for PM to 54 or 94 h for luminometry or the Bronx box, respectively. These results support the utility of LRPs as a screening test for the surveillance of MDR tuberculosis.
Temporal and Geographical Distribution and Overlap of Penner Heat-Stable Serotypes and Pulsed-Field Gel Electrophoresis Genotypes of
Campylobacter jejuni
Isolates Collected from Humans and Chickens in Finland during a Seasonal Peak
Authors: Kärenlampi R. , Rautelin H. , Hakkinen M. , Hänninen M.-L.
Published: October 2003

The association of Penner heat-stable serotypes and pulsed-field gel electrophoresis genotypes of 208 human and 30 chicken
Campylobacter jejuni
isolates was studied. Overall, 46% of the human strains had overlapping sero- and genotype combinations with chicken strains. The percentage was reduced to 31% for strains that were considered temporally related. This suggests common environmental sources.
Epidemiological Study of Resistance to Nalidixic Acid and Other Antibiotics in Clinical
Yersinia enterocolitica
O:3 Isolates
Authors: Capilla S. , Goñi P. , Rubio M. C. , Castillo J. , Millán L. , Cerdá P. , Sahagún J. , Pitart C. , Beltrán A. , Gómez-Lus R.
Published: October 2003

Forty-six
Yersinia enterocolitica
O:3 clinical isolates resistant to nalidixic acid were studied. The use of molecular typing techniques, other indicators of resistance patterns, the plasmid profile, and the presence of genes that encode aminoglycoside-modifying enzyme production suggested to us a clonal dissemination of the studied strains.
Staphylococcal Exanthematous Disease in a Newborn Due to a Virulent Methicillin-Resistant
Staphylococcus aureus
Strain Containing the TSST-1 Gene in Europe: an Alert for Neonatologists
Authors: van der Mee-Marquet Nathalie , Lina Gérard , Quentin Roland , Yaouanc-Lapalle Hélène , Fièvre Christine , Takahashi Naoto , Etienne Jerome
Published: October 2003

We report a case of staphylococcal exanthematous disease in a newborn due to a toxic shock syndrome toxin 1- and SEC-producing methicillin-resistant
Staphylococcus aureus
strain and alert neonatologists to the probable emergence in France of the neonatal toxic shock syndrome-like exanthematous disease in newborns previously described in Japan. We advise neonatologists to pay careful attention to clinical parameters and to prescribe appropriate tests: platelet count, serum C-reactive protein concentration, and Vβ2-positive T-cell counts.
Molecular Characterization of a Strain of Group A Streptococcus Isolated from a Patient with a Psoas Abscess
Authors: Lau Susanna K. P. , Woo Patrick C. Y. , Yim Tak-ching , To Amanda P. C. , Yuen Kwok-yung
Published: October 2003

We report the first case of a primary group A streptococcus (GAS) psoas abscess in a 31-year-old woman. The psoas abscess was preceded by an episode of acute pharyngitis. The M-protein gene (
emm
) and streptolysin S structural gene (
sagA
) were present in the isolate, with no significant amino acid differences from previously described sequences of M1 GAS isolates. Multilocus sequence typing (MLST) showed that the isolate belonged to MLST sequence type (MLST-ST) 28, the predominant MLST-ST associated with invasive disease caused by M1 isolates.
Serial Granulocyte Transfusions as a Treatment for Sepsis Due to Multidrug-Resistant
Pseudomonas aeruginosa
in a Neutropenic Patient
Authors: Lin Ying-Wei , Adachi Souichi , Watanabe Ken-Ichiro , Umeda Katsutsugu , Nakahata Tatsutoshi
Published: October 2003

The emergence of multidrug-resistant
Pseudomonas aeruginosa
(MRPA) has become a major clinical problem. We successfully treated MRPA sepsis in a neutropenic patient undergoing peripheral blood stem cell transplantation with serial granulocyte transfusions. Granulocyte transfusion should be considered as a treatment for severe infection in patients with neutropenia.
Occurrence of Renal and Pulmonary Syndrome in a Region of Northeast Germany Where Tula Hantavirus Circulates
Authors: Klempa Boris , Meisel Helga , Räth Silvana , Bartel Jan , Ulrich Rainer , Krüger Detlev H.
Published: October 2003

Hantavirus species Tula (TULV) is carried by European common voles (
Microtus
spp.). Its pathogenic potential for humans is unknown. In a rural region of northeast Germany, a 43-year-old man became ill with fever, renal syndrome, and pneumonia. Typing of late acute- and convalescent-phase sera by focus reduction neutralization assay revealed the presence of neutralizing antibodies against TULV. Moreover, we detected TULV genetic material in
Microtus arvalis
animals that were trapped at places only a few kilometers from the home village of the patient. Phylogenetic analysis of completely sequenced genomic S segments from three virus strains grouped them within a third genetic lineage of the TULV species. This is the first case of hemorrhagic fever with renal syndrome and pulmonary involvement which can be associated with TULV infection.
Successful Outcome of DisseminatedFusariumInfection with Skin Localization Treated with Voriconazole and Amphotericin B-Lipid Complex in a Patient with Acute Leukemia
Authors: Durand-Joly Isabelle , Alfandari Serge , Benchikh Zinnédine , Rodrigue Marion , Espinel-Ingroff Ana , Catteau Benoit , Cordevant Christophe , Camus Daniel , Dei-Cas Eduardo , Bauters Francis , Delhaes Laurence , De Botton Stéphane
Published: October 2003

A disseminatedFusarium oxysporuminfection with skin localization was diagnosed in a woman with a relapse of B-acute leukemia during induction chemotherapy. The infection was refractory to amphotericin B-lipid complex alone but responded successfully when voriconazole was added.
Paronychia Due toPrevotella biviaThat Resulted in Amputation: Fast and Correct Bacteriological Diagnosis Is Crucial
Authors: Riesbeck Kristian
Published: October 2003

Prevotella biviais mainly associated with endometritis. The case of a patient with paronychia in a thumb due toP. biviaresulting in osteitis and amputation is reported. The species was not acknowledged in the first bacterial culture 2 weeks before surgery.
Semiclassical behavior of the degenerate four-wave mixing without slowly varying amplitude approximation
Authors: Farzad M H , Tavassoly M T
Published: October 2003

In this study, a semiclassical version of the degenerate four-wave mixing (DFWM) solution without slowly varying amplitude (SVA) approximation is investigated. The quadrature fluctuations of the output modes exhibit an oscillatory behavior with respect to that of the corresponding SVA modes. Furthermore, the variation of the two quadrature fluctuations of the combined mode, plotted against the normalized coupling constant κL, oscillates. Beyond a certain value of κL, the two quadratures oscillate in opposite directions, which implies that the squeezing effect of DFWM without the SVA approximation oscillates around that of the SVA. In addition, the squeezing effect in DFWM without SVA approximation depends on the refractive index of the medium and increases sharply upon the increase of the latter. This study also shows that the super-Poissonian behavior of the conjugate mode is preserved but is oscillatory.

PACS No.: 42.65.Hw
The vacuum polarization in two-dimensional noncommutative QED
Authors: Brandt F T , McKeon D.G.C.
Published: October 2003

The one-loop vacuum polarization tensor in noncommutative spinor QED in two dimensions is computed. A first-order formalism is used to simplify the interaction vertices for the vector field. Although the form of the gauge field-spinor interaction is chosen so as to vanish at tree level, as the noncommuting parameter goes to zero, the vacuum polarization is nontrivial in this limit.

PACS No.: 12.20.m
Dimensional reduction of the spinning string in a background gravitational field
Authors: McKeon D.G.C.
Published: October 2003

The superfield and equivalent component field formulations of the N = 1 spinning string in the presence of a background gravitational field are given. It is shown how dimensional reduction of this spinning string gives rise to an N = 2 spinning particle with global 0(2) symmetry. A distinction between different versions of the action for the N = 2 spinning particle is noted.

PACS No.: 12.60.Jv
New method for reducing the general formula for lattice specific heat to the Einstein and Nernst-Lindemann approximations
Authors: Irons F E
Published: October 2003

To reduce the general formula for lattice specific heat to Einstein's formula of 1907, one traditionally models the spectrum of lattice modes-of-vibration as a set of independent oscillators all of one frequency, ν1. Not only is this a poor representation of a real solid, but no formula is provided for the frequency ν1, which has to be determined empirically. We offer a new and more compelling method for reducing the general formula to Einstein's formula. The reduction involves a simple mathematical approximation, proceeds without any reference to independent oscillators all of one frequency, and leads to a formula for the characteristic frequency, ν1, equal to the mean modal frequency. The mathematical approximation is valid at all but low temperatures, thereby providing insight into the failure of Einstein's formula at low temperatures. A simple extension of the new method leads to the NernstLindemann formula for specific heat, proposed in 1911 on the basis of trial and error and currently without a sound theoretical basis. Empirical values (from the literature) of the frequencies that characterize the Einstein, the NernstLindemann, and also the Debye formulae are all in support of the present theory.

PACS Nos.: 65.40.Ba, 01.55.+b
Recursive calculation of nonprimitive coupling and recoupling brakets
Authors: Butler P H , Joyce W P , McAven L F , Searle B G
Published: October 2003

The concept of coupling coefficients of angular momentum for the rotation group chain [Formula: see text] can be extended to representations of any group-chain factorisation by defining the generalised notion of a braket. We give a unified approach to recoupling coefficients (rccs), vector-coupling coefficients (vccs), and 3j phases for all group-chain transformations. Category theory is the appropriate tool for studying the representations of groups and algebras. The explicit use of category theory leads to a new recursion scheme for the calculation of brakets. We derive specialisations for calculating nonprimitive rccs and nonprimitive vccs from primitive rccs, primitive vccs, and 3j phases. This new recursion scheme forms the algorithmic core of Racah v4. Racah v4 is a software package developed at the University of Canterbury to calculate group representation coefficients (brakets).

PACS Nos.: 02.20.Mp, 03.65.Fd, 31.15.p, 31.15.Hz, 02.10.Ws
Factorization of second-order matrix differential operators and a matrix Darboux transformation
Authors: Bracken Paul
Published: October 2003

It is shown that a class of matrix Schrödinger operators can be factored into a product of two first-order matrix operators. The equations that relate the elements in these first-order operators to the elements of the potential matrix of the Schrödinger operator are obtained. They are found to be coupled first-order differential equations in the variables of the first-order matrix operators. Finally, an example of a factorization of a matrix operator is obtained, and a general solution associated to a value of the spectral parameter is given. PACS Nos.: 02.30.Mq, 12.39.Pn
Numerical loading of a Maxwellian probability distribution function
Authors: Lewandowski J L.V
Published: October 2003

A renormalization procedure for the numerical loading of a Maxwellian probability distribution function (PDF) is formulated. The procedure, which involves the solution of three coupled nonlinear equations, yields a numerically loaded PDF with improved properties for higher velocity moments. This method is particularly useful for low-noise particle-in-cell simulations with electron dynamics. PACS Nos.: 52.35.Py, 52.30.Jb, 52.55.Fa
Analytical and numerical modeling of pullout capacity and interaction between hexagonal wire mesh and silty sand backfill under an in-soil pullout test
Authors: Teerawattanasuk Chairat , Bergado Dennes T , Kongkitkul Warat
Published: October 2003

During the pullout test, the pullout clamping system was modified and installed inside the pullout box with confinement from the fill material, hereinafter called the in-soil pullout test, which significantly reduced the necking phenomenon and the displacements mobilized during the pullout test. Subsequently, an analytical model was developed to predict the in-soil pullout resistance. In addition, a numerical modeling analysis, under the three-dimensional stress field conditions using the FLAC3D (fast Lagrangian analysis continua) program, was carried out to simulate the behavior of in-soil pullout tests. The laboratory in-soil pullout test results were then compared with the corresponding data obtained from the analytical and numerical modeling methods. The in-soil pullout resistance was greater than the corresponding result from previous pullout tests wherein the clamping system was conventionally installed outside the pullout box. The predicted pullout resistance results from FLAC3D agreed reasonably with the results from laboratory tests and with the results from the analytical modeling. The interaction coefficients, R, applied in the finite difference modeling of in-soil pullout tests were 0.90 and 0.65 for zinc-coated and polyvinyl chloride (PVC) coated hexagonal wire meshes, respectively. The predicted and measured pullout resistance of zinc-coated hexagonal wire mesh is approximately 20% greater than that of PVC-coated hexagonal wire mesh at the same applied normal pressure, because of the higher stiffness, EA, and higher shear stiffness, ks, of the zinc-coated mesh.Key words: hexagonal wire mesh, in-soil pullout test, pullout resistance, analytical modeling, numerical modeling.
Unstable behaviour of sand and its implication for slope instability
Authors: Chu J , Leroueil S , Leong W K
Published: October 2003

Results of some constant shear-drained (CSD) tests conducted on both loose and dense sand are presented. Using the critical state line and a modified state parameter, a new framework for analysing the instability of granular soil slopes is proposed. The test data were examined and interpreted using the new framework. Instability lines for sand with different void ratios were established within this framework. The conditions for the occurrence of instability in both contractive and dilative granular soil slopes under various shear stress levels were examined using the proposed framework.Key words: deformation, laboratory tests, liquefaction, sands, shear strength, slope stability.
Diffusion and consumption of oxygen in unsaturated cover materials
Authors: Mbonimpa M , Aubertin M , Aachib M , Bussière B
Published: October 2003

Covers installed over waste disposal sites are used to control water and gas exchanges with the surrounding environment. One example involves covers built to limit oxygen flux to sulphidic mining and milling wastes, which can be the source of acidic leachate. In this paper, the authors present an approach to evaluate oxygen flux and its controlling parameters, the effective diffusion coefficient De and reaction (consumption) rate coefficient Kr. A laboratory experimental procedure to determine these two parameters simultaneously is described, and the proposed interpretation method is presented with a few sample results. New analytical solutions are developed to calculate oxygen flux through covers with capillary barrier effects (CCBE). The proposed solutions are compared with results ensuing from a numerical treatment of Fick's laws. Specific applications of these analytical solutions are presented and discussed.Key words: unsaturated soils, covers, capillary barrier, Fick's laws, oxygen diffusion, acid mine drainage, analytical solutions, numerical solutions.
Design and construction of a deep excavation in soft soils adjacent to the Shanghai Metro tunnels
Authors: Hu Z F , Yue Z Q , Zhou J , Tham L G
Published: October 2003

This paper presents the design and construction of a deep excavation for building foundations in saturated soil. This deep excavation was of particular interest because it was located above and beside the Shanghai Metro tunnels. The twin Shanghai Metro tunnels had to be in full operation during the deep excavation. Potential large deformation of the twin tunnels was one of the main concerns during the design and construction for the deep excavation. The paper discusses in detail the criteria and measures for controlling the soil and tunnel deformation. The measures included cast-in-place concrete diaphragm walls with bracing structural members, pumping consolidation, cementsoil mix pile systems, and rational excavation procedures. A simplified theoretical method was proposed to estimate the increment in undrained shear strength in a soft clay layer due to pumping consolidation. Furthermore, conventional finite element methods were used to predict the soil vertical and horizontal displacements induced by the excavation. Using the design and construction methods discussed in the paper, the settlement and horizontal displacement of the tunnels were successfully controlled within 5.0 mm and 9.0 mm, respectively. The curvature of longitudinal deformation curve of the tunnels was less than 1/15 000. The horizontal displacement of the braced diaphragm walls was less than 0.12% of the total excavation depth. Key words: Metro tunnels, saturated soft soil, deep excavation, design, construction, ground improvement, case studies.
Bearing capacity of a sand layer on clay by finite element limit analysis
Authors: Shiau J S , Lyamin A V , Sloan S W
Published: October 2003

Rigorous plasticity solutions for the ultimate bearing capacity of a strip footing resting on a sand layer over clay soil are obtained by applying advanced upper and lower bound techniques. The study compares these solutions with other published results and investigates the effect of various strength and geometry parameters. Assuming the soil layers obey an associated flow rule, the results presented typically bound the collapse load to within ±10% or better.Key words: limit analysis, bearing capacity, layered soils, finite elements.
An oedometer test study on the preconsolidation stress of glaciomarine clays
Authors: Grozic J L.H , Lunne T , Pande S
Published: October 2003

Stress history is usually determined by interpreting the results of oedometer tests to obtain the preconsolidation stress using traditional methods such as those proposed by Casagrande and Janbu. Both these methods are based on the assumption that the soil experiences a change in stiffness, from a stiff response to a soft response, close to the preconsolidation stress. Disturbed soils, however, especially overconsolidated clays of low plasticity, exhibit a soft response at low stresses, thereby making the interpretation of oedometer tests using traditional methods extremely difficult. Using data mainly from the Haltenbanken area, offshore Norway, a study was undertaken to investigate the various methods and testing procedures available to determining stress history. Oedometer verification tests were also performed on reconstituted specimens to compare interpreted values with the actual applied preconsolidation stress. This paper describes the results of the study by illustrating the variation in the interpretation methods and testing procedures used to determine preconsolidation stress.Key words: preconsolidation stress, yield stress, overconsolidated, low plastic clays, oedometer test, stress history.