bluuebunny/crossref_metadata_2025 huggingface dataset:
Identification of
Haemophilus influenzae
Serotypes by Standard Slide Agglutination Serotyping and PCR-Based Capsule Typing
Authors: LaClaire Leslye L. , Tondella Maria Lucia C. , Beall David S. , Noble Corie A. , Raghunathan Pratima L. , Rosenstein Nancy E. , Popovic Tanja
Published: January 2003

To resolve discrepancies in slide agglutination serotyping (SAST) results from state health departments and the Centers for Disease Control and Prevention (CDC), we characterized 141 of 751 invasive
Haemophilus influenzae
isolates that were identified in the United States from January 1998 to December 1999 through an active, laboratory-based, surveillance program coordinated by the CDC. We found discrepancies between the results of SAST performed at state health departments and those of PCR capsule typing performed at the CDC for 56 (40%) of the isolates characterized: 54 isolates that were identified as a particular serotype by SAST were shown to be unencapsulated by PCR, and two isolates that were reported as serotypes b and f were found to be serotypes f and e, respectively, by PCR. The laboratory error most likely to affect the perceived efficacy of the conjugate
H. influenzae
type b (Hib) vaccine was the misidentification of isolates as serotype b: of 40 isolates identified as serotype b by SAST, 27 (68%) did not contain the correlating capsule type genes. The frequency of errors fell substantially when standardized reagents and routine quality control of SAST were used during a study involving three laboratories. An overall 94% agreement between SAST and PCR results showed that slide agglutination could be a valid and reliable method for serotyping
H. influenzae
if the test was performed correctly, in accordance with standardized and recommended procedures. An ongoing prospective analysis of all
H. influenzae
surveillance isolates associated with invasive disease in children less than 5 years old will provide more accurate national figures for the burden of invasive disease caused by Hib and other
H. influenzae
serotypes.
Evaluation of Broth Microdilution Testing Parameters and Agar Diffusion Etest Procedure for Testing Susceptibilities of
Aspergillus
spp. to Caspofungin Acetate (MK-0991)
Authors: Espinel-Ingroff Ana
Published: January 2003

The NCCLS M38-A document does not describe guidelines for testing caspofungin acetate (MK-0991) and other echinocandins against molds. This study evaluated the susceptibilities of 200 isolates of
Aspergillus fumigatus
,
A. flavus
,
A. nidulans
,
A. niger
, and
A. terreus
to caspofungin (MICs and minimum effective concentrations [MECs]) by using standard RPMI 1640 (RPMI) and antibiotic medium 3 (M3), two inoculum sizes (10
3
and 10
4
CFU/ml), and two MIC determination criteria (complete [MICs-0] and prominent growth inhibition [MICs-2]) at 24 and 48 h. Etest MICs were also determined. In general, caspofungin MIC-2 and MEC pairs were comparable with both media and inocula (geometric mean ranges of MECs and MICs, respectively, with larger inoculum: 0.12 to 0.64 μg/ml and 0.12 to 0.44 μg/ml with RPMI versus 0.04 to 0.51 μg/ml and 0.03 to 0.21 μg/ml with M3); however, MEC results were less influenced by testing conditions than MICs, especially with the larger inoculum. Overall, the agreement between caspofungin Etest MICs and broth dilution values was higher with MECs obtained with M3 (>90%) and the large inoculum than under the other testing conditions. Because RPMI is a more stable and chemically defined medium than M3, the determination at 24 h of the easier visual MECs with RPMI and the inoculum recommended in the M38-A document appears to be a suitable procedure at present for in vitro testing of caspofungin against
Aspergillus
spp. Future in vitro correlations with in vivo outcome of both microdilution and Etest procedures may detect more-relevant testing conditions.
Thymidine-Dependent Small-Colony Variants of
Staphylococcus aureus
Exhibit Gross Morphological and Ultrastructural Changes Consistent with Impaired Cell Separation
Authors: Kahl Barbara C. , Belling Gunnar , Reichelt Rudolf , Herrmann Mathias , Proctor Richard A. , Peters Georg
Published: January 2003

Thymidine-dependent small-colony variants (SCV) of
Staphylococcus aureus
exhibited unusual colony morphology with “fried-egg” or pinpoint white colonies on agar plates and pleomorphic cocci as determined by Gram staining. Electron microscopy revealed enlarged cocci with incomplete or multiple cross walls consistent with impaired cell separation. Fried-egg SCV phenotypes could be reversed by thymidine supplementation.
Identification of
Candida
spp. by Randomly Amplified Polymorphic DNA Analysis and Differentiation between
Candida albicans
and
Candida dubliniensis
by Direct PCR Methods
Authors: Bautista-Muñoz Consuelo , Boldo Xavier M. , Villa-Tanaca Lourdes , Hernández-Rodríguez César
Published: January 2003

Because
Candida
species have innately highly variable antifungal susceptibilities, the availability of a fast and reliable species identification test is very important so that suitable and effective therapeutic measures may be taken. Using three oligonucleotide primers, we established a randomly amplified polymorphic DNA (RAPD) analysis method that enabled direct identification of the most common opportunistic pathogenic
Candida
species. RAPD analysis revealed a characteristic molecular fingerprint for each
Candida
species. Differences between the profiles for
Candida albicans
and
C. dubliniensis
were evident. RAPD analysis is a relatively easy, reproducible, and reliable technique that can be useful in providing genetic fingerprints for the identification of strains. In addition, a collection of different
C. albicans
strains was identified by a specific PCR based on multiple secreted aspartic proteinase (
SAP
) genes and the dipeptidyl aminopeptidase (
DAP2
) gene. Our findings demonstrate that PCR based upon the
SAP
and
DAP2
sequences is a simple, rapid, clear, and direct technique for the identification and differentiation of
C. albicans
and
C. dubliniensis
.
Changes in Patterns of Antimicrobial Susceptibility and Integron Carriage among
Shigella sonnei
Isolates from Southwestern Korea during Epidemic Periods
Authors: Oh Jae Young , Yu Hak Sun , Kim Sung Ki , Seol Seong Yong , Cho Dong Taek , Lee Je Chul
Published: January 2003

Shigella sonnei
isolates from southwestern Korea during the epidemic periods of 1998 to 2000 were genetically related. The antimicrobial susceptibilities of the outbreak-related isolates changed annually. All isolates carried class 2 integrons, and the outbreak-related isolates from 1999 also carried class 1 integrons. The antimicrobial susceptibilities of
S. sonnei
isolates are readily changed by antibiotic selective pressures, and integrons are responsible for resistance to antimicrobial agents commonly used to treat shigellosis.
Phenotypes and Genotypes of Erythromycin-Resistant Pneumococci in Italy
Authors: Montanari Maria Pia , Mingoia Marina , Cochetti Ileana , Varaldo Pietro Emanuele
Published: January 2003

Of 120 erythromycin-resistant pneumococci isolated in Italian hospitals, 39 (32.5%) were M-type isolates, carrying the
mef
gene alone. The
mef
gene was also detected, together with
erm
(AM), in one constitutively resistant isolate and in five isolates of the partially inducible phenotype. Among the 45
mef
-positive isolates, 25 (55.6%) carried
mef
(A) and 20 (44.4%) carried
mef
(E) as observed from PCR-restriction fragment length polymorphism analysis of a 1,743-bp amplicon. The same result was obtained by a similar method applied to a more common 348-bp amplicon.
Antigen Detection Assay for Identification ofPenicillium marneffeiInfection
Authors: Chaiyaroj Sansanee C. , Chawengkirttikul Runglawan , Sirisinha Stitaya , Watkins Pramuan , Srinoulprasert Yuttana
Published: January 2003

Two recently produced monoclonal antibodies were used to develop an antigen capture enzyme-linked immunosorbent assay (ELISA) for rapid diagnosis ofPenicillium marneffei. The method was evaluated with 53 patients with culture-confirmed penicilliosis and 240 controls. The diagnostic sensitivity, specificity, and accuracy of the ELISA were 92.45, 97.5, and 96.59%, respectively.
Comparison of Washing and Swabbing Procedures for Collecting Genital Fluids To Assess Shedding of Human Immunodeficiency Virus Type 1 (HIV-1) RNA in Asymptomatic HIV-1-Infected Women
Authors: Andréoletti Laurent , Grésenguet Gérard , Chomont Nicolas , Matta Mathieu , Quiniou Yann , Si-Mohamed Ali , Bélec Laurent
Published: January 2003

Human immunodeficiency virus type 1 (HIV-1) RNA was detected by means of ultrasensitive reverse transcription-PCR assay of 19 cervicovaginal lavage, 21 cervical mucus, 18 vaginal wall, and 17 vaginal fornix paired samples from 25 asymptomatic HIV-1-infected women (76, 84, 72, and 68%, respectively;
P
> 0.5). Levels of HIV-1 RNA in cervicovaginal wash samples were highly correlated with those in paired endocervical mucus samples (
r
= 0.71;
P
= 0.0006), indicating that cervicovaginal washing and endocervical swabbing are equivalent collection procedures.
Characterization of the First Extended-Spectrum Beta-Lactamase-ProducingSalmonellaIsolate Identified in Canada
Authors: Mulvey Michael R. , Soule Geoff , Boyd David , Demczuk Walter , Ahmed Rafiq
Published: January 2003

A singleSalmonella entericaserovar Typhimurium isolate with an UT2 phage type producing an extended-spectrum beta-lactamase (ESBL) was identified in Canada in 2000. The isolate harbored two plasmids, one containing ablaTEM-1gene and the other containing ablaSHV-2agene. The ESBL gene was located on a 70-kb transferable plasmid which also carried tetracycline and trimethoprim resistance elements.
Epidemiology and Antimicrobial Susceptibilities of 111
Campylobacter fetus
subsp.
fetus
Strains Isolated in Québec, Canada, from 1983 to 2000
Authors: Tremblay Carole , Gaudreau Christiane , Lorange Manon
Published: January 2003

The epidemiology and antimicrobial susceptibilities of 111
Campylobacter fetus
subsp
. fetus
strains isolated from 103 patients from 1983 to 2000 in Québec, Canada, were determined. The median number of patients infected annually with this bacteria was seven, with an incidence of 0.1 per 100,000 population. The male-to-female ratio was 1.1 to 1.0. The patients originated from 13 of the 18 Québec socioeconomic regions. The age range of the patients was 6 months to 90 years old, 53% being ≥70 years old and 2% being <20 years old. The isolation site was blood for 69% of the patients, stools for 20%, and other body fluids for 11% of them. Three patients suffered a relapse, with the same strain being isolated from the same site at different times as confirmed by pulse-field gel electrophoresis. All isolates were susceptible to ampicillin, gentamicin, meropenem, and imipenem, with 90% minimal inhibitory concentrations of 4, 1, 0.12, and ≤0.06 μg/ml, respectively. Three percent and two percent of the strains were, respectively, resistant and intermediate to ciprofloxacin. Thirty-four percent of the strains were resistant to tetracycline. There was a nonsignificant increase in resistance to ciprofloxacin (
P
= 0.27) and to tetracycline (
P
= 0.65) in recent years. The percentages of intermediate and resistant MICs were, respectively, 12 and 1% for cefotaxime and 71 and 0% for erythromycin. All strains were β-lactamase negative.
Processing Sputum Specimens in a Refrigerated Centrifuge Does Not Increase the Rate of Isolation of
Mycobacterium tuberculosis
Authors: Selvakumar N. , Govindan Dakshayani , Chandu Naik Ashok , Frieden Thomas R. , Narayanan P. R.
Published: January 2003

A total of 1,047 sputum samples from pulmonary tuberculosis patients was collected in cetyl pyridinium chloride-sodium chloride solution. Each sample was divided into two parts and randomly allocated for the isolation of
Mycobacterium tuberculosis
, with one part to be processed by the standard method and the other by a modified method. In the standard method, the samples were processed by using nonrefrigerated centrifuges, while in the modified method, they were processed by using a refrigerated centrifuge. Fifty-seven samples that yielded contaminants were excluded, and the remaining 990 samples were taken up for analysis. The rates of isolation of
M. tuberculosis
with the standard and modified methods were 48.6 and 48.1%, respectively, and the difference was not statistically significant (McNemar's test;
P
> 0.5). However, 51% of the positive cultures were isolated within 2 weeks with the modified method compared to 37% with the standard method (chi-square test;
P
< 0.001). The results of the study reveal that processing of sputum samples in a refrigerated centrifuge does not improve the rate of isolation but will result in rapid isolation of
M. tuberculosis
.
Prevalence of
Candida
Species, Including
Candida dubliniensis
, in Singapore
Authors: Yang C. W. , Barkham T. M. S. , Chan F. Y. , Wang Y.
Published: January 2003

We present data on the prevalence of
Candida
species isolated from inpatients in three Singapore hospitals and from vaginal samples collected at community clinics. Strikingly, ∼20% of the isolates from blood and vaginal samples were fluconazole-resistant species. By analyzing species-specific gene sequence signatures, we identified
Candida dubliniensis
from both groups of patients.
Evaluation of MicroScan Autoscan for Identification of
Pseudomonas aeruginosa
Isolates from Cystic Fibrosis Patients
Authors: Saiman Lisa , Burns Jane L. , Larone Davise , Chen Yunhua , Garber Elizabeth , Whittier Susan
Published: January 2003

Accurate identification of gram-negative bacilli from cystic fibrosis (CF) patients is essential. Only 57% (108 of 189) of nonmucoid strains and 40% (24 of 60) of mucoid strains were definitively identified as
Pseudomonas aeruginosa
with MicroScan Autoscan. Most common misidentifications were
Pseudomonas fluorescens
-
Pseudomonas putida
(i.e., the strain was either
P. fluorescens
or
P. putida
, but the system did not make the distinction and yielded the result
P. fluorescens/putida
) and
Alcaligenes
spp. Extending the incubation to 48 h improved identification, but 15% of isolates remained misidentified. The MicroScan Autoscan system cannot be recommended for the identification of
P. aeruginosa
isolates from CF patients.
Analysis of
Mycobacterium avium
Complex Isolates from Blood Samples of AIDS Patients by Pulsed-Field Gel Electrophoresis
Authors: Kunimoto D. Y. , Peppler M. S. , Talbot J. , Phillips P. , Shafran S. D.
Published: January 2003

A molecular analysis of the first
Mycobacterium avium
complex (MAC) blood isolates from 177 patients from 10 Canadian cities revealed that each cluster of indistinguishable strains consisted of isolates from epidemiologically unrelated patients in the same city or region. This study supports the premise that acquisition of MAC from a common environmental source occasionally occurs.
Discrimination of Human Pathogenic Subspecies of
Francisella tularensis
by Using Restriction Fragment Length Polymorphism
Authors: Thomas Rebecca , Johansson Anders , Neeson Brendan , Isherwood Karen , Sjöstedt Anders , Ellis Jill , Titball Richard W.
Published: January 2003

We describe the use of two insertion sequence elements (ISFtu1 and ISFtu2) in
Francisella tularensis
to type strains by restriction fragment length polymorphism (RFLP). The RFLP profiles of 17 epidemiologically unrelated isolates were determined and compared. Our results showed that RFLP profiles can be used to assign
F. tularensis
strains into five main groups corresponding to strains of
F. tularensis
subsp.
tularensis
,
F. tularensis
strain ATCC 6223, strains of
F. tularensis
subsp.
holarctica
, strains of
F. tularensis
subsp.
holarctica
from Japan, and
F. tularensis
subsp.
mediaasiatica
. The results confirm the genetic identities of these subspecies and also support the suggestion that strains of
F. tularensis
subsp.
holarctica
from Japan should be considered members of a separate biovar. These findings should support future studies to determine the genetic differences between strains of
F. tularensis
at the whole-genome level.
Rapid Detection of Classical Swine Fever Virus by a Portable Real-Time Reverse Transcriptase PCR Assay
Authors: Risatti G. R. , Callahan J. D. , Nelson W. M. , Borca M. V.
Published: January 2003

A fluorogenic-probe hydrolysis (TaqMan)-reverse transcriptase PCR assay for classical swine fever virus (CSFV) was developed and evaluated in experimentally infected swine. The assay detected CSFV, representing different phylogenetic groupings, but did not amplify viral RNA from related pestiviruses. The assay met or exceeded the sensitivity (1 to 100 50% tissue culture infective doses per ml) of viral cultures of samples from experimentally infected animals. Viral RNA was detected in nasal and tonsil scraping samples 2 to 4 days prior to the onset of clinical disease. The assay can be performed in 2 h or less, thus providing a rapid method for the diagnosis of classical swine fever.
Meningitis Due to Mixed Infection with Penicillin-Resistant and Penicillin-Susceptible Strains of
Streptococcus pneumoniae
Authors: Chaves Fernando , Campelo Carolina , Sanz Francisca , Otero Joaquin R.
Published: January 2003

Streptococcus pneumoniae
is the major cause of bacterial meningitis. We report a case of meningitis due to a mixed infection with two distinct strains of
S. pneumoniae
: one penicillin-resistant strain of serotype 9V and one penicillin-susceptible strain of serotype 7. The two strains exhibited different pulsed-field gel electrophoresis profiles.
Duration of Infection and Proportion of Pigs Persistently Infected with Porcine Reproductive and Respiratory Syndrome Virus
Authors: Wills Robert W. , Doster Alan R. , Galeota Judith A. , Sur Jung-Hyang , Osorio Fernando A.
Published: January 2003

Understanding the dynamics of porcine reproductive and respiratory syndrome virus (PRRSV) persistence in individual pigs is essential to the development of successful control programs. The objectives of this study were to investigate the proportion of inoculated pigs that become persistently infected with PRRSV and the duration of their infection. Additionally, different diagnostic techniques that detect persistent infections were compared. Twenty-eight 35-day-old pigs were inoculated with PRRSV. Serum and tonsil biopsy samples were collected on days 0, 7, 14, and 28 and then approximately monthly thereafter until day 251 postinoculation (p.i.). Tonsil, lymph node, and lung samples were collected following euthanasia on day 251 p.i. Virus was isolated from serum and tonsil biopsy samples that had been collected through days 28 and 56 p.i., respectively. Viral RNA was detected by reverse transcription (RT)-PCR in serum and tonsil biopsy samples that had been collected through day 251 p.i., although no serum samples collected from days 84 to 196 p.i. were positive and the presence of infectious PRRSV was not detected by swine bioassay of tissue samples collected at necropsy. The results confirmed that RT-PCR is more sensitive than virus isolation in identifying PRRSV-infected pigs. Six pigs that were persistently infected through days 225 or 251 p.i. remained seropositive throughout the study, although one pig had an enzyme-linked immunosorbent assay sample-to-positive ratio that was only slightly above the cutoff value of 0.40. Twenty of 28 tonsil biopsy samples collected on day 84 p.i. were positive by RT-PCR compared to only 1 positive biopsy sample out of 28 collected on day 119 p.i. The study's results indicate that most pigs clear PRRSV within 3 to 4 months, but that some may remain persistently infected for several months.
Evaluation of a PCR Assay for Detection of
Streptococcus pneumoniae
in Respiratory and Nonrespiratory Samples from Adults with Community-Acquired Pneumonia
Authors: Murdoch David R. , Anderson Trevor P. , Beynon Kirsten A. , Chua Alvin , Fleming Angela M. , Laing Richard T. R. , Town G. Ian , Mills Graham D. , Chambers Stephen T. , Jennings Lance C.
Published: January 2003

Streptococcus pneumoniae
is the most common cause of community-acquired pneumonia, but it is undoubtedly underdiagnosed. We used a nested PCR assay (targeting the pneumolysin gene) to detect
S. pneumoniae
DNA in multiple sample types from 474 adults with community-acquired pneumonia and 183 control patients who did not have pneumonia. Plasma or buffy coat samples were PCR positive in only 6 of the 21 patients with positive blood cultures for
S. pneumoniae
and in 12 other patients (4 of whom had no other laboratory evidence of
S. pneumoniae
infection). Buffy coat samples from two control patients (neither having evidence of
S. pneumoniae
infection), but no control plasma samples, were PCR positive. Although pneumococcal antigen was detected in the urine from 120 of 420 (29%) patients, only 4 of 227 (2%) urine samples tested were PCR positive. Overall, 256 of 318 (81%) patients had PCR-positive sputum samples, including 58 of 59 samples from which
S. pneumoniae
was cultured. Throat swab samples from 229 of 417 (55%) patients were PCR positive and, in those who produced sputum, 96% also had positive PCR results from sputum. Throat swabs from 73 of 126 (58%) control patients were also PCR positive. We conclude that the pneumolysin PCR assay adds little to existing diagnostic tests for
S. pneumoniae
and is unable to distinguish colonization from infection when respiratory samples are tested.
Single-Nucleotide Polymorphisms (SNPs) in Human β-Defensin 1: High-Throughput SNP Assays and Association with
Candida
Carriage in Type I Diabetics and Nondiabetic Controls
Authors: Jurevic Richard J. , Bai Mai , Chadwick Robert B. , White Theodore C. , Dale Beverly A.
Published: January 2003

β-Defensins are cationic antimicrobial peptides expressed in epithelia. They exhibit antibacterial, antifungal, and antiviral properties. Defensins are a component of the innate immune response, and it has been proposed that they have a protective role in the oral cavity. Previous studies have shown that human β-defensin 1 (hBD-1) is constitutively expressed in oral epithelial cells but that expression varies between individuals. We tested the hypothesis that genetic variations in defensin peptide expression may be associated with opportunistic infections. This may be critical in the immunocompromised patient population, in which innate immune responses may have a relatively more important role. Oral
Candida
carriage status and the presence of six single-nucleotide polymorphisms (SNPs) in the
DEFB1
gene encoding hBD-1 were evaluated in type I diabetic patients (
n
= 43) and nondiabetic controls (
n
= 50). Genomic DNA was obtained from buccal swabs. Portions of the
DEFB1
gene were amplified, and each SNP was analyzed by a TaqMan assay, standardized with control DNA of known genotype.
Candida
carriage status was determined from unstimulated saliva on CHROMagar plating medium. A low level of
Candida
carriage was defined as ≤350 CFU/ml. A high level of
Candida
carriage was seen in 44% of the diabetic subjects but only in 28% of the nondiabetic controls (
P
< 0.05).
C. albicans
predominated; however, diabetic subjects, especially those with high levels of carriage, showed an increased proportion of
Candida glabrata
and
C. tropicalis.
There was a strong association between an SNP in the 5′ untranslated region (C→G at position −44) and
Candida
carriage in both groups. Among individuals in the diabetic population who had the SNP allele 2 (G), 58% had low CFU, while 6% had high CFU. The C→G SNP at position −44 is associated with low levels of
Candida
carriage. The resultant odd ratios are statistically significant for a protective effect (odd ratios, 25 for diabetic subjects and 8.5 for nondiabetic subjects). These results indicate that genetic variations in the
DEFB1
gene encoding hBD-1 may have a major role in mediating and/or contributing to susceptibility to oral infection.
Participation in screening for colorectal cancer based on a faecal occult blood test is improved by endorsement by the primary care practitioner
Authors: Cole S.R. , Young G. , Byrne D. , Guy J. , Morcom J.
Published: January 2003

OBJECTIVES: To investigate the influence of general practitioner (GP) endorsement on participation in screening for colorectal cancer based on a faecal occult blood test (FOBT). SETTING: South Australian residents (n=2400), in 1999, aged >50 years. METHODS: Random selection of three groups (GP1, GP2, GP3) from two general practices and of one group (ER) from the federal electoral roll; n=600 per group. Without previous communication or publicity, subjects were posted an offer of screening by immunochemical FOBT. The GP1 and ER groups were invited without indication that their GP was involved; GP2 received an invitation indicating support from the practice; and GP3 received an invitation on practice letterhead and signed by a practice partner. A reminder was posted at 6 weeks. Participation was defined as return of correctly completed FOBT sample cards within 12 weeks. RESULTS: Participation rates were: GP1 192/600 (32.0%), GP2 228/600 (38.0%), and GP3 244/600 (40.7%); &khgr;2=10.2, p=0.006. Both GP2 and GP3 differed significantly from GP1 (odds ratio (OR) 0.77, 95% confidence interval (95% CI) 0.60 to 0.98 and relative risk (RR)=0.69, 95% CI 0.54 to 0.87 respectively). ER (193/600 (32.2%)) and GP1 were not significantly different. Age but not sex was significantly associated with participation. Overall test positivity rate was 4.6%; five malignancies were found in the 918 who performed FOBT. CONCLUSIONS: Association of a GP of recent contact with a screening offer in the form of a personalised letter of invitation achieves better participation than does the same letter from a centralised screening unit that does not mention the GP. Thus, GP enhanced participation is achievable without their actual involvement. Additional strategies are needed to further improve participation.
Repeated mammographic screening reduces breast cancer mortality along the continuum of age
Authors: Broeders M.J.M. , Verbeek A.L.M. , Straatman H. , Peer P.G.M. , Pasker-de Jong P.C.M. , Beex L.V.A.M. , Hendriks J.H.C.L. , Holland R.
Published: January 2003

OBJECTIVE: The optimal age boundaries for breast cancer screening are still under debate. A case-referent design was used to describe the effect of mammographic screening on breast cancer mortality along the continuum of age, based on a 20 year follow up period. SETTING: The population based breast cancer screening programme in Nijmegen, The Netherlands, which has biennially invited women over 35 years since 1975. METHODS: Cases, defined as women who died from primary breast cancer between 1987 and 1997, were selected from the group of women who received at least one invitation to the screening programme. For 157 cases, 785 women from the same group were selected as referents. Information on the index screening (the screening examination preceding diagnosis of the case) was collected for both cases and referents. The risk of dying from breast cancer was calculated per 10 year moving age group for women who had attended the index screening versus those who had not. RESULTS: The youngest 10 year age group showing an effect in our study were women aged 45–54 at their index screening. Breast cancer mortality for women in this group who attended the index screening was 32% lower, although not significant, than for women who did not (odds ratio (OR) 0.68, 95% confidence interval (95% CI) 0.33 to 1.41). This reduction in risk was not explained solely by an effect in women over 50 because the OR in women aged 45–49 was 0.56 (95% CI 0.20 to 1.61). Reductions in mortality became smaller with increasing age. Nevertheless, for women over 60 at index screening, participation in screening over a maximum 4 year period before diagnosis of the case yielded protective effects at least up to an age around 80. CONCLUSIONS: Although our results are based on a relatively small number of cases, they suggest that even in a programme with a 2 year screening interval there may be a benefit of starting screening around age 45. Also older women who participate at least once every 4 years still have much to gain from screening.
Monitoring women's experiences during three rounds of breast cancer screening: results from a longitudinal study
Authors: Drossaert C.H.C. , Boer H. , Seydel E.R.
Published: January 2003

OBJECTIVES: (a) To monitor experiences of women during three successive rounds of breast screening; (b) to examine the impact of previous experiences (obtained either immediately after the latest mammogram or shortly before the subsequent one) on reattendance; and (c) to examine which factors are associated with the experience of pain and distress during screening. SETTING: The Dutch Breast Cancer Screening Programme METHODS: 2657 women completed a baseline measurement (response rate 67%) about 8 weeks after they had been invited for an initial mammogram (T1). Actual participation data of these women in the second and third rounds of screening were collected. Follow up questionnaires were sent to subgroups of the sample at different times: shortly before the second screening (T2; response rate 86%), shortly after the second screening (T3; response rate 85%), shortly before the third screening (T; response rate 80%), and shortly after the third screening (T5; response rate 78%). RESULTS: Most women were satisfied with the first screening round and remained positive about subsequent screens. Although pain and anxiety were not uncommon, only a few (10%–15%) experienced moderate or severe levels of distress or pain. Experiences were relatively stable: women who experienced pain in the first screen were more likely to experience pain in subsequent screens (r values from 0.39 to 0.50). Fear of breast cancer was associated with increased distress related to mammography and, to a lesser extent, with increased pain during the mammography. Evidence was found for a relief effect: women were more positive about their previous screen when asked shortly after this screen, than when asked just before the subsequent one. Previous experiences (obtained either proximally or distally) were only slightly predictive for future attendance. CONCLUSION: Experiences during mammography are fairly stable. Negative experiences were generally not a reason to drop out of the programme.
An investigation into the number of appointment changes and queries arising as a result of extending breast screening to older women in the United Kingdom
Authors: Brown J. , Garvican L. , Moss S.
Published: January 2003

OBJECTIVE: To compare the number of telephone queries and appointment changes requested by women aged 65–69 with women aged 50–64 . SETTING: Department of Health funded demonstration study of extending breast screening to women of 65–69. METHODS: A survey was conducted for 1 week, each month, over the period of a year. Data were collected on the date of the query, the age of the woman, whether and why the appointment was changed, and whether the location for screening was changed. RESULTS: The proportion of telephone queries or appointment changes was significantly more for women aged 50–64 years (p<0.001), 29.7% of women invited aged 50–64 compared with 26.5% of women invited aged 65–69. The main reason for changing the appointments was inconvenience for both age groups. CONCLUSIONS: Administrative costs associated with inviting an older woman for breast screening are no more than those for a woman aged 50–64. The number of telephone calls was high in both age groups, which has resource implications for extending the breast screening programme. The extent of appointment queries or changes needs to be considered in the funding of future population screening programmes with preallocated appointment systems.
Estimate of population coverage with the prostate specific antigen (PSA) test to screen for prostate cancer in a metropolitan area of northern Italy
Authors: Russo A. , Autelitano M. , Bellini A. , Bisanti L.
Published: January 2003

The use of the prostate specific antigen (PSA) test in the period 1999–2000 in a population of 311 822 men, aged 40 years or more, resident in Milan, Italy, was examined. Data were drawn from the outpatient database of the local health information system. A total of 139 350 PSA tests were used in 83 943 subjects. Overall, 26.9% of the male population aged 40 or older, with no history of prostate cancer, received a PSA test in the 2 year study period. For subjects older than 50 the rate rose to 34%. Results show a high coverage of the male population in northern Italy with screening using the PSA test for prostate cancer.
What is the risk of mortality for people who are screen positive in a diabetes screening programme but who do not have diabetes on biochemical testing? Diabetes screening programmes from a public health perspective
Authors: Spijkerman A. , Griffin S. , Dekker J. , Nijpels G. , Wareham N.J.
Published: January 2003

OBJECTIVES: To assess mortality risk in people classified by the Cambridge risk score (CRS), a previously validated simple screening tool for undiagnosed type 2 diabetes that uses only information routinely available in primary care. SETTING: Random sample of the general population between 50 and 75 years of age in Hoorn, The Netherlands METHODS: The results of the CRS were compared with the gold standard for diabetes, the oral glucose tolerance test (OGTT) results classified according to the World Health Organisation (WHO) 1999 diagnostic criteria. Cox’s proportional hazards regression was used to assess the risk of mortality of screen positive and screen negative people. RESULTS: 154 people out of the total population of 2297 had previously undiagnosed diabetes and 113 (73%) of these would have been detected with the CRS (true positive). However, the CRS identified a much larger group (n=1037) who were positive for the score, but who did not have diabetes on biochemical testing (false positive). Unadjusted risk of mortality was highest in the true positive group (3.40 95% confidence interval (95% CI, 2.15 to 5.38)), intermediate in false positive people (2.62 (2.00 to 3.43)), and lowest in false negative people (1.50 (0.55 to 4.09)) with the true negative group as reference. Adjustment for age and sex resulted in similar risk estimates for all three groups, but mortality risk was significantly increased only in false positive and true positive groups compared with the true negative group. CONCLUSIONS: People who have a positive risk score are at high risk of mortality whether or not subsequent testing shows them to have diabetes. Direct public health interventions in this high risk population may be appropriate.
Reconstructing ecosystem dynamics in the central Pacific Ocean, 19521998. I. Estimating population biomass and recruitment of tunas and billfishes
Authors: Cox Sean P , Martell Steven J.D. , Walters Carl J , Essington Timothy E , Kitchell James F , Boggs Christofer , Kaplan Isaac
Published: January 2003

Commercial yield of tunas in the central Pacific increased severalfold between 1952 and 1998. We developed age-structured production models that incorporate information from multiple fisheries to estimate population biomass and recruitment trends of tunas (Thunnus alalunga, Thunnus albacares, Thunnus obesus, and Katsuwonus pelamis) and billfish in the central north Pacific (0°N to 40°N and 130°E to 150°W). Our results suggest that all tuna stocks remain above 40% of 1950s levels, whereas blue marlin (Makaira nigricans) declined to 21% and swordfish (Xiphias gladius) to 56%. Estimated biomasses of juvenile bigeye (T. obsesus) and yellowfin (T. albacares) tuna increased to 112 and 129%, respectively, of 1950s levels. Juvenile albacore (T. alalunga) decreased during the 1970s and 1980s but recovered to historical highs (121%) in recent years. Skipjack (K. pelamis) remained relatively stable between 1952 and 1980, declined by 35% between 1981 and 1990, and then increased to 68% of 1950s levels. These changes generally represent decreases in top predators and increases in small tunas, which make up their prey. Application of stock assessment methods set in a food web context provides an important step toward developing a method that recognizes fishery exploitation as a component of ecosystem dynamics.
Identifying the weakest link: simulating adaptive management of the reintroduction of a threatened fish
Authors: Bearlin Andrew R , Schreiber E S.G , Nicol Simon J , Starfield A M , Todd Charles R
Published: January 2003

As part of an ongoing program of management for a critically endangered fish, we explored adaptive management as a method to overcome pervasive uncertainty regarding the reintroduction of trout cod (Maccullochella macquariensis Cuvier). We simulated the entire adaptive management cycle to explore the suitability of the approach for guiding threatened species management and to identify problems and barriers to "learning by doing". During the planning phase, a number of compromises were identified between specification of goals and objectives, the available management options, and current monitoring capacity. Undertaking a simulation of the implementation of alternate adaptive approaches to this reintroduction provided a number of insights into adaptive management in general. First, identifying the weak link in the process of inference emphasized the need to consider whether goals and objectives are achievable and meaningful and whether they complement monitoring and (or) any other limitations of the system. Second, in natural resource management, it is crucial to negotiate objectives in the light of what one can measure. Third, although there are lessons to be learned from each stage of the adaptive management cycle, there is value in simulating the entire adaptive management cycle, including management actions, monitoring, and the states of the system that lead to management intervention.
Differential energy allocation of alternative male tactics in masu salmon (Oncorhynchus masou)
Authors: Koseki Yusuke , Maekawa Koji
Published: January 2003

To compare energy allocation to gonad, relative to soma, between alternative male tactics (mature parr and migratory males) in masu salmon (Oncorhynchus masou), we quantified energy contents in somatic and testicular tissues for the two tactics from two lake-run populations (Shikaribetsu Lake and Shumarinai Reservoir) in Hokkaido, northern Japan. Mass-specific testicular energy (kJ·g1) was lower in migratory males than in mature parr in the Shikaribetsu population, but not in the Shumarinai population. The consistent pattern was observed in somatic energy, suggesting that mass-specific energy reflects population environment rather than inherent allocation pattern. Despite this confounding effect of specific energy, total testicular energy (kJ), relative to total somatic energy, was higher in mature parr in both populations. We suggest that strong sperm competition involved with sneak spawning is responsible for an increased testicular investment in mature parr.
Bayesian markrecapture estimation with an application to a salmonid smolt population
Authors: Mäntyniemi Samu , Romakkaniemi Atso
Published: January 2003

We developed a Bayesian probability model for markrecapture data. Three alternative versions of the model were applied to two sets of data on the abundance of migrating Atlantic salmon (Salmo salar) smolt populations, and the results were then compared with those of two widely used maximum likelihood models (Petersen method and a model using stratified data). Our model follows the basic principles of stochastic models presented for stratified data. In contrast to the earlier models, our model can deal with sparse data. Moreover, even weak dependencies between the studied parameters and the possible factors affecting them can be used to improve the plausibility of the estimates. The assumptions behind our approach are more realistic than those of earlier models, taking into account such factors as overdispersion, which is expected to be present in the markrecapture data of salmon smolts because of their schooling behavior. Our examples also show that assumptions about the model structure can have a substantial impact on the resulting inferences on the size of the smolt run, especially in terms of the precision of the estimate.
Larval sand lance (Ammodytes sp.) in the diet of small juvenile wolffish (Anarhichas spp.): predatory interactions in frontal water masses off western Greenland
Authors: Munk Peter
Published: January 2003

The predatory behaviour of two species of juvenile wolffish (Anarhichas lupus and Anarhichas minor) was studied during a field campaign across a frontal area off western Greenland. The study focused on ontogenetic changes in prey-type and -size preference of the wolffish and their predatory impact on a cohabiting population of larval sand lance (Ammodytes sp.). Sampling took place along a cross-shelf transect at latitude 66°20' N, and the analysis is based on stomach contents of assembled wolffish (25 cm in length) and abundance estimates of plankton and fish. An ontogenetic change in wolffish prey preference was evident as a dietary shift from copepods and smaller amphipods to larger amphipods and fish larvae. The inclusion of fish larvae in the wolffish diet led to a marked increase in prey biomass, and fish larvae constituted up to 77% of diet biomass in the largest juveniles caught. Wolffish selectively targeted the smaller-sized part of the larval sand lance population; hence, larval vulnerability increased with decreasing size. Comparison between estimated predation rates and abundances of predator and prey indicated larval predation mortalities of up to 5% per day, with mortality peaking in the vicinity of a hydrographic front. Hence, findings suggest substantial predation pressure on larvae, primarily related to larval size and distribution.
Interactive effects of temperature and salinity on otolith chemistry: challenges for determining environmental histories of fish
Authors: Elsdon Travis S , Gillanders Bronwyn M
Published: January 2003

The concentrations of elements and isotopes in fish otoliths may provide a method of reconstructing movements of fish by differentiating between water bodies of different temperatures and salinities. However, before otoliths can be used to reconstruct environmental histories of fish, it is necessary to assess the effects of seawater temperature and salinity on otolith microchemistry. Using controlled laboratory experiments, juvenile black bream, Acanthopagrus butcheri (family Sparidae), were reared for 50 days in aquaria of varying temperatures and salinities using three experimental designs: temperature × salinity, temperature only, and salinity only. Temperature and salinity interacted to significantly affect the elemental concentration ratios of Sr:Ca and Ba:Ca and the concentrations of isotopes δ13C and δ18O in otoliths. The single-factor experiments showed that temperature significantly affected the concentration ratios of Sr:Ca and Ba:Ca and the concentrations of δ13C and δ18O in otoliths, whereas salinity alone did not affect the concentration ratios of any elements but did affect both isotopes. The concentration ratios of Mg:Ca and Mn:Ca varied considerably among fish within the same treatment level and showed little or no effects due to temperature and (or) salinity. The significant interactive effects of temperature and salinity on otolith microchemistry highlight the need for a multifactorial approach to testing hypotheses regarding the environmental histories of fish.
Sulfate absorption in Aplysia californica gut: glucocorticoid inhibition
Authors: Gerencser George A , Zhang Jianliang , Levin Randy
Published: January 2003

Mucosal membranes of foregut epithelia of Aplysia californica contain a sodium/sulfate symporter. Dexamethasone inhibited the absorptive activity of the sodium/sulfate symporter, whereas amiloride had no effect on it. It appears that glucocorticoids or their molluscan equivalent play a role in the overall regulation of sulfate homeostasis by the A. californica gut.
Multimodal communication in crayfish: sex recognition during mate search by male Austropotamobius pallipes
Authors: Acquistapace Patrizia , Aquiloni Laura , Hazlett Brian A , Gherardi Francesca
Published: January 2003

The role of multiple signals in sex recognition in the crayfish Austropotamobius pallipes was investigated by analyzing the main channels (chemical or chemical plus visual) used by males during mate search. The behavioral responses of males were recorded when they were exposed to four different treatments: female odor only, male odor only, female odor plus visual cues, and male odor plus visual cues. Males did not respond to chemical cues alone emitted by a female, but required both chemical and visual stimuli. The high-flow conditions of the aquatic habitat occupied, the restricted mating period, and the low density of the population examined may explain the use of both cues in sex recognition by males.
Consequences of forest fragmentation on territory quality of male Ovenbirds breeding in western boreal forests
Authors: Mazerolle Daniel F , Hobson Keith A
Published: January 2003

We evaluated the effects of forest fragmentation caused by agriculture on arthropod prey biomass and vegetation structure found in territories of male Ovenbirds (Seiurus aurocapillus) breeding in the southern boreal mixed woods of Saskatchewan, Canada. The objective of this study was to determine if previously documented differences in pairing success of male Ovenbirds in contiguous forests and forest fragments in our study area were associated with differences in arthropod prey biomass and vegetation structure between contiguous and fragmented forests. A secondary objective was to examine the correspondence between vegetation and arthropods to evaluate whether vegetation cues could be useful for birds attempting to predict future arthropod biomass during territory selection. Our results indicate that both vegetation structure and arthropod prey composition in Ovenbird territories differed between fragmented and contiguous forests, whereas total arthropod biomass did not. Furthermore, the correspondence of vegetation with arthropod prey composition and total prey biomass was weak, a result that questions the use of vegetation structure by male Ovenbirds for predicting future prey availability during territory selection. Overall, the current extent of forest fragmentation in our study area is not likely reducing pairing success of territorial male Ovenbirds by lowering the biomass of arthropod prey. However, landscape differences in vegetation structure could influence pairing success of male Ovenbirds in forest fragments by reducing suitable microhabitats for nesting or by increasing habitat suitability for nest predators and Brown-headed Cowbird (Molothrus ater) parasites.