bluuebunny/crossref_metadata_2025 huggingface dataset:
Serum Interferon (IFN)-Neutralizing Antibodies and Bioactivities of IFNs in Patients with Severe Type II Essential Mixed Cryoglobulinemia
Authors: Scagnolari Carolina , Casato Milvia , Bellomi Francesca , De Pisa Francesca , Turriziani Ombretta , Coviello Rossella , Pirro Maria Rosaria , Dianzani Ferdinando , Antonelli Guido
Published: January 2003

The efficacy of alpha interferon (IFN-α) in the treatment of severe type II essential mixed cryoglobulinemia (EMC) has been reported previously. In some patients, the development of neutralizing antibodies to recombinant IFN-α (rIFN-α) can affect the clinical response achieved with rIFN-α; a second treatment with natural IFN-α preparations may reinduce the clinical response. In the present study the ability of leukocyte IFN (LeIFN) to restore the response was investigated from a pharmacodynamic viewpoint. Specifically, the pharmacodynamic profiles of different IFN-α preparations were studied by measuring the serum neopterin levels and the levels of expression of protein MxA mRNA in in vivo peripheral blood mononuclear cells in two patients with EMC whose resistance to rIFN-α2a treatment increased concomitantly with the development of neutralizing antibodies. These markers were measured before injection and at 24 and 48 h after a single injection of rIFN-α2a, consensus IFN [(C)IFN], or LeIFN. No increase or only a slight increase in MxA mRNA levels was detectable after administration of rIFN-α2a or (C)IFN, whereas a significant increase (≥10-fold) in MxA mRNA expression was recorded following administration of LeIFN. The neutralizing antibodies to rIFN-α2a cross-react with (C)IFN. Sera from these patients neutralized most but not all of the subtypes present in the natural IFN-α (LeIFN) mixture, and no significant increase in neopterin levels was observed after these patients were switched to LeIFN treatment. In summary, the data demonstrate that the problem of neutralizing antibodies still exists and that LeIFN may induce an increase in the level of MxA mRNA expression but not an increase in neopterin levels in patients who are resistant to treatment with rIFN-α2a or (C)IFN.
Analysis of Linear B-Cell Epitopes of the Nucleoprotein of Ebola Virus That Distinguish Ebola Virus Subtypes
Authors: Niikura Masahiro , Ikegami Tetsuro , Saijo Masayuki , Kurata Takeshi , Kurane Ichiro , Morikawa Shigeru
Published: January 2003

Ebola virus consists of four genetically distinguishable subtypes. We developed monoclonal antibodies (MAbs) to the nucleoprotein (NP) of Ebola virus Zaire subtype and analyzed their cross-reactivities to the Reston and Sudan subtypes. We further determined the epitopes recognized by these MAbs. Three MAbs reacted with the three major subtypes and recognized a fragment containing 110 amino acids (aa) at the C-terminal extremity. They did not show specific reactivities to any 10-aa short peptides in Pepscan analyses, suggesting that these MAbs recognize conformational epitope(s) located within this region. Six MAbs recognized a fragment corresponding to aa 361 to 461 of the NP. Five of these six MAbs showed specific reactivities in Pepscan analyses, and the epitopes were identified in two regions, aa 424 to 430 and aa 451 to 455. Three MAbs that recognized the former epitope region cross-reacted with all three subtypes, and one that recognized the same epitope region was Zaire specific. One MAb, which recognized the latter epitope region, was reactive with Zaire and Sudan subtypes but not with the Reston subtype. These results suggest that Ebola virus NP has at least two linear epitope regions and that the recognition of the epitope by MAbs can vary even within the same epitope region. These MAbs showing different subtype specificities might be useful reagents for developing an immunological system to identify Ebola virus subtypes.
Measurement of Human Cytomegalovirus Loads by Quantitative Real-Time PCR for Monitoring Clinical Intervention in Transplant Recipients
Authors: Li Haijing , Dummer J. Stephen , Estes Wray R. , Meng Shufang , Wright Peter F. , Tang Yi-Wei
Published: January 2003

Quantitative monitoring of human cytomegalovirus (HCMV) infection is helpful in determining appropriate antiviral management of transplant recipients. Quantitative PCR technologies have demonstrated accuracy in measuring systemic HCMV loads. A total of 298 consecutive whole-blood specimens submitted to the Clinical Virology Laboratory at Vanderbilt University Medical Center from 15 February to 31 October 1999 were included in the study. In addition to a qualitative colorimetric microtiter plate PCR assay (MTP-PCR) and a semiquantitative pp65 antigenemia assay, each specimen was measured for HCMV loads by a quantitative PCR assay performed on an ABI PRISM 7700 Sequence Detection System (TaqMan). Compared to results of the MTP-PCR, the sensitivity, specificity, positive predictive value, and negative predictive value were 70.5, 97.5, 87.8, and 92.8% for the antigenemia assay and were 96.7, 92.0, 75.6, and 99.1% for the TaqMan assay, respectively. There was a high correlation between antigenemia values and HCMV loads as determined by the TaqMan (
r
= 0.989;
P
< 0.001). Antigenemia values of 0, 1 to 10, 11 to 100, 101 to 1,000, and over 1,000 positive cells per 2 × 10
5
leukocytes corresponded to median HCMV loads measured by TaqMan of 125, 1,593, 5,713, 16,825, and 5,425,000 copies/ml, respectively. Corresponding to antigenemia values of 1 to 2, 10, and 50 positive cells per 2 × 10
5
leukocytes, HCMV viral loads of 1,000, 4,000, and 10,000 copies/ml are proposed as cutoff points for initiating antiviral therapy in patient groups with high, intermediate, and low risk of CMV diseases.
Commercial Assay for Detection of
Giardia lamblia
and
Cryptosporidium parvum
Antigens in Human Fecal Specimens by Rapid Solid-Phase Qualitative Immunochromatography
Authors: Garcia Lynne S. , Shimizu Robyn Y. , Novak Susan , Carroll Marilyn , Chan Frank
Published: January 2003

The ImmunoCard STAT!
Cryptosporidium
/
Giardia
rapid assay (Meridian Bioscience, Inc.) is a solid-phase qualitative immunochromatographic assay that detects and distinguishes between
Giardia lamblia
and
Cryptosporidium parvum
in aqueous extracts of human fecal specimens (fresh, frozen, unfixed, or fixed in 5 or 10% formalin or sodium acetate-acetic acid-formalin). By using specific antibodies, antigens specific for these organisms are isolated and immobilized on a substrate. After the addition of appropriate reagents, a positive test is detected visually by the presence of a gray-black color bar (regardless of the intensity) next to the organism name printed on the test device. A control is included in the device. Steps include tube preparation (buffer, patient specimen, conjugates A and B), testing (addition of sample onto the test device), and visual reading (total time, 12 min). Test performance was evaluated with known positive and negative stool specimens (170 specimens positive for
Giardia
and 231 specimens negative for
Giardia
) (85 specimens positive for
Cryptosporidium
and 316 specimens negative for
Cryptosporidium
); they were tested with trichrome, iron-hematoxylin, or modified acid-fast stains or the Meridian Bioscience, Inc.,
Giardia
/
Cryptosporidium
Merifluor combination reagent; specimens with discrepant results were retested by using the Merifluor combination reagent. On the basis of the results of the reference methods, the sensitivities, specificities, and positive and negative predictive values were as follows: for
G. lamblia
, 93.5, 100, 100, and 95.5%, respectively; for
C. parvum
, 98.8, 100, 100, and 99.7%, respectively. False-negative results for
G. lamblia
were obtained with specimens with low parasite numbers (
n
= 7) or specimens containing trophozoites only (
n
= 3); one specimen with a false-negative result contained numerous cysts. The one specimen false negative for
C. parvum
was confirmed to be positive by immunofluorescence. No cross-reactivity was seen with 10 different protozoa (152 challenges), nine different helminths (35 challenges), or human cells (4 challenges) found in fecal specimens. This rapid test system may be very beneficial in the absence of trained microscopists; however, for patients who remain symptomatic after a negative result, the ova and parasite examination and special stains for other coccidia and the microsporidia should always remain options.
Detection of
Mycoplasma genitalium
by PCR Amplification of the 16S rRNA Gene
Authors: Jensen Jørgen Skov , Borre Martin B. , Dohn Birthe
Published: January 2003

In order to develop a species-specific PCR for the detection of
Mycoplasma genitalium
, the sequence of 1,490 bases of the 16S rRNA gene was determined for
M. genitalium
G37 (type strain) and four Danish isolates of
M. genitalium
. The sequences of the four Danish strains, mutually different with respect to their MgPa gene, were 100% homologous, although they carried a single common base substitution compared to the type strain. Among members of the
Mycoplasma pneumoniae
phylogenetic cluster,
M. genitalium
showed the most-prominent homology to the 16S rRNA sequence of
M. pneumoniae
(98% homology). From regions showing the least homology to the
M. pneumoniae
16S rRNA gene sequence, primers were chosen to amplify DNA from
M. genitalium
only. Two sets of primers were selected for their ability to detect <10 to 50
M. genitalium
genome copies without cross-reactions with
M. pneumoniae
. The performance of these primers was compared to the performance of two pairs of primers amplifying parts of the MgPa adhesin gene; 1,030 randomly selected specimens submitted for
Chlamydia trachomatis
culture were screened with one of the 16S rRNA gene primer sets. A total of 41 specimens were found to be positive for this gene; 40 of these could be confirmed by one of the MgPa primer sets, whereas the other MgPa primer set detected only 21 positive specimens out of 40. These results indicate that estimates of the prevalence of
M. genitalium
in various populations using MgPa PCR primers could be incorrectly low if the PCR primers are located in variable regions of the MgPa gene.
Subtyping of
Salmonella enterica
Serotype Enteritidis Strains by Manual and Automated
Pst
I-
Sph
I Ribotyping
Authors: Clark Clifford G. , Kruk Tamara M. A. C. , Bryden Louis , Hirvi Yolanda , Ahmed Rafiq , Rodgers Frank G.
Published: January 2003

Salmonella enterica
subsp.
enterica
serotype Enteritidis is not readily subtyped beyond the level of phage type (PT). A recently developed method for ribotyping of this organism, which uses a mixture of
Pst
I and
Sph
I (PS) for restriction of DNA (PS ribotyping), has proved useful for further subtyping of a number of PTs of this organism, including PT 4. However, it has not been extensively tested with PT 8. In the present study the PS ribotyping method was used to investigate outbreaks of both
S. enterica
serotype Enteritidis PT 4 and PT 8 and provided subtyping data that were consistent with information obtained from epidemiologic investigations. The method proved to be more discriminatory than phage typing and pulsed-field gel electrophoresis (PFGE) combined and was useful for investigating a pseudo-outbreak involving isolates that had identical PTs and PFGE types but that could not be linked epidemiologically. Several PS ribotypes were found within the cluster of isolates indistinguishable by other subtyping methods, confirming the epidemiologic findings. Although the PS ribotyping method proved to have a superior discriminatory ability in resolving clusters, it did not have high enough throughput for use in outbreak investigations. This method has therefore been adapted for use in automated ribotyping with a RiboPrinter, and the results were compared with those obtained by manual ribotyping. Both methods produce equivalent results and are useful for obtaining epidemiologically relevant subtyping data for
S. enterica
serotype Enteritidis, including PT 8 strains not extensively tested previously.
Identification of Urovirulence Traits inEscherichia coliby Comparison of Urinary and RectalE. coliIsolates from Dogs with Urinary Tract Infection
Authors: Johnson James R. , Kaster Nicholas , Kuskowski Michael A. , Ling Gerald V.
Published: January 2003

Spontaneously occurring urinary tract infection (UTI) in dogs was exploited as an experiment of nature to gain insights into UTI pathogenesis in humans. Concurrent urinary and rectalEscherichia coliisolates from 37 dogs with UTI were compared with respect to phylogenetic background, O antigens, and extended virulence genotype. In 54% of the UTI episodes, the dog's urinary and rectal isolates represented the same strain. Urinary isolates differed dramatically from rectal-only isolates in that they derived predominantly fromE. coliphylogenetic group B2, expressed typical (human) UTI-associated O antigens, and possessed many virulence-associated genes, most notablypapelements (P fimbriae),papG(adhesin) allele III,sfa/focandsfaS(S fimbriae),hly(hemolysin),fyuA(yersiniabactin),iroN(siderophore), andompT(outer membrane protease T). The 20 urinary isolates that corresponded with the host's predominant rectal strain were no less virulent according to the markers analyzed than were the 17 urinary isolates that differed from the host's predominant rectal strain. These findings suggest that UTI pathogenesis is similar in dogs and humans, provide added support for the special-pathogenicity over the prevalence hypothesis of UTI pathogenesis, and identify numerous specific virulence-associated factors as significant correlates of urovirulence.
Characterization ofMycobacterium tuberculosisComplex DNAs from Egyptian Mummies by Spoligotyping
Authors: Zink Albert R. , Sola Christophe , Reischl Udo , Grabner Waltraud , Rastogi Nalin , Wolf Hans , Nerlich Andreas G.
Published: January 2003

Bone and soft tissue samples from 85 ancient Egyptian mummies were analyzed for the presence of ancientMycobacterium tuberculosiscomplex DNA (aDNA) and further characterized by spoligotyping. The specimens were obtained from individuals from different tomb complexes in Thebes West, Upper Egypt, which were used for upper social class burials between the Middle Kingdom (since ca. 2050 BC) and the Late Period (until ca. 500 BC). A total of 25 samples provided a specific positive signal for the amplification of a 123-bp fragment of the repetitive element IS6110, indicating the presence ofM. tuberculosisDNA. Further PCR-based tests for the identification of subspecies failed due to lack of specific amplification products in the historic tissue samples. Of these 25 positive specimens, 12 could be successfully characterized by spoligotyping. The spoligotyping signatures were compared to those in an international database. They all show either anM. tuberculosisor anM. africanumpattern, but none revealed anM. bovis-specific pattern. The results from a Middle Kingdom tomb (used exclusively between ca. 2050 and 1650 BC) suggest that these samples bear anM. africanum-type specific spoligotyping signature. The samples from later periods provided patterns typical forM. tuberculosis. This study clearly demonstrates that spoligotyping can be applied to historic tissue samples. In addition, our results do not support the theory thatM. tuberculosisoriginated from theM. bovistype but, rather, suggest that humanM. tuberculosismay have originated from a precursor complex probably related toM. africanum.
Detection of
Borrelia lonestari
, Putative Agent of Southern Tick-Associated Rash Illness, in White-Tailed Deer (
Odocoileus virginianus
) from the Southeastern United States
Authors: Moore IV Victor A. , Varela Andrea S. , Yabsley Michael J. , Davidson William R. , Little Susan E.
Published: January 2003

To determine if white-tailed deer may serve as a reservoir host for
Borrelia lonestari
, we used a nested PCR for the
Borrelia
flagellin gene to evaluate blood samples collected from deer from eight southeastern states. Seven of 80 deer (8.7%) from 5 of 17 sites (29.4%) had sequence-confirmed evidence of a
B. lonestari
flagellin gene by PCR, indicating that deer are infected with
B. lonestari
or another closely related
Borrelia
species. Our findings expand the known geographic range of
B. lonestari
and provide the first evidence of this organism in a vertebrate other than humans.
Identification of
Mycobacterium avium
Genotypes with Distinctive Traits by Combination of IS
1245
-Based Restriction Fragment Length Polymorphism and Restriction Analysis of
hsp65
Authors: Oliveira R. S. , Sircili M. P. , Oliveira E. M. D. , Balian S. C. , Ferreira-Neto J. S. , Leão S. C.
Published: January 2003

One-hundred eight
Mycobacterium avium
isolates from pigs, humans, birds, and bovines were typed by the IS
1245
-based restriction fragment length polymorphism (RFLP) method and PCR-restriction enzyme analysis (PRA) of
hsp65
. Nine clusters of isolates showing more than 80% similarity in their RFLP profiles were detected. The largest cluster (cluster B) included 32 of 79 pig isolates (40.5%), 3 of 25 human isolates (12%), and 1 of 2 bovine isolates, comprising 33% of all isolates. The second largest cluster (cluster A) included 18 pig isolates (22.8%) and 6 human isolates (24%). Six smaller clusters included six pig isolates (clusters C and D), four and two human isolates (clusters E and F, respectively), two pig isolates (cluster I), and two pig isolates plus one bovine isolate and the avian purified protein derivative strain (cluster H). Cluster G represented the “bird-type” profile and included the bird isolate in this series, one pig isolate, plus reference strain R13. PRA revealed four allelic variants. Seventy-seven isolates were identified as
M. avium
PRA variant I, 24 were identified as
M. avium
PRA variant II, 6 were identified as
M. avium
PRA variant III, and 1 was identified as
M. avium
PRA variant IV. Except for three isolates from cluster B, each of the RFLP clusters was associated with a single PRA pattern. Isolates with unique (nonclustered) RFLP profiles were distributed between PRA variants I and II, and there was one unique isolate of PRA variant IV. These observations are consistent with divergent evolution within
M. avium
, resulting in the emergence of distinct lineages with particular competence to infect animals and humans.
Accuracy of a Commercial Enzyme-Linked Immunosorbent Assay for CagA in Patients from Brazil with and without Gastric Carcinoma
Authors: Rocha Andreia Maria Camargos , Rocha Gifone Aguiar , Santos Adriana , de Oliveira Celso Affonso , Queiroz Dulciene Maria Magalhães
Published: January 2003

We validated a commercial enzyme-linked immunosorbent assay for the detection of anti-CagA antibodies in Brazilian patients with
Helicobacter pylori
infection. The test presented high sensitivity (97.4%) and specificity (88.9%) when employed in patients without gastric carcinoma. However, in gastric carcinoma patients, the test was neither sensitive nor specific enough to detect
cagA-
positive
H. pylori
infection.
Prevalence of
agr
Specificity Groups among
Staphylococcus aureus
Strains Colonizing Children and Their Guardians
Authors: Shopsin B. , Mathema B. , Alcabes P. , Said-Salim B. , Lina G. , Matsuka A. , Martinez J. , Kreiswirth B. N.
Published: January 2003

PCR-based assays were used to evaluate
agr
locus nucleotide polymorphism for the identification of
agr
autoinducer receptor specificity groups within a population of
Staphylococcus aureus
isolates colonizing children and their guardians. All isolates could be assigned to one of three major
agr
groups that had similar prevalences, regardless of whether isolates were implicated in transmission of
S. aureus
within families. Among healthy carriers,
agr
groups I to III appear to be equally fit, which may reflect selection for the coexistence of
S. aureus
strains in a population.
Evaluation of a Method for Identification of
Candida dubliniensis
Bloodstream Isolates
Authors: Sancak Banu , Rex John H. , Paetznick Victor , Chen Enuo , Rodriguez Jose
Published: January 2003

To evaluate methods for differentiating
Candida albicans
and
Candida dubliniensis
, 772 putative
C. albicans
bloodstream isolates were tested for growth at 37 and 42°C. Isolates showing no growth at 42°C, abundant chlamydospore production, and the sugar assimilation pattern of the type strain were confirmed by DNA-based procedures to be
C. dubliniensis
.
Detection and Treatment of Bloodstream Infection: Laboratory Reporting and Antimicrobial Management
Authors: Munson Erik L. , Diekema Daniel J. , Beekmann Susan E. , Chapin Kimberle C. , Doern Gary V.
Published: January 2003

We analyzed antimicrobial use in 509 episodes of clinically significant bloodstream infection to assess the impact that microbiology laboratory reporting had on antimicrobial management. Most therapy interventions occurred at the time of phlebotomy and after notification of Gram stain results by telephone. Release of antimicrobial susceptibility data had the least impact on antimicrobial management.
Staphylococcus lugdunensis
Carrying the
mecA
Gene Causes Catheter-Associated Bloodstream Infection in Premature Neonate
Authors: Tee Wen Sim Nancy , Soh Shui Yen , Lin Raymond , Loo Liat Hui
Published: January 2003

A premature neonate had a catheter-associated bloodstream infection due to
Staphylococcus lugdunensis
. The MIC of oxacillin for the strain was >256 μg/ml, and the
mecA
gene of
S. lugdunensis
was detected by PCR. The infection was resolved after removal of the line and treatment with vancomycin for 2 weeks.
Deciphering an Outbreak of Drug-Resistant
Mycobacterium tuberculosis
Authors: Dahle Ulf R. , Sandven Per , Heldal Einar , Mannsaaker Turid , Caugant Dominique A.
Published: January 2003

There have been ample warnings that multidrug-resistant (MDR) tuberculosis (TB) will continue to emerge if countries do not strengthen their control of TB. In low-incidence European countries, however, these warnings have been substantiated mainly by outbreaks in association with human immunodeficiency virus (HIV)-positive patients. The aim of this study was to investigate an outbreak of infection with MDR and drug-resistant
Mycobacterium tuberculosis
that was diagnosed among 20 HIV-negative patients living in Norway. Of these, 19 were immigrants from East Africa and one was an ethnic Norwegian. We wanted to find out if transmission had taken place in Norway or abroad and to identify the genetic basis of drug resistance. The strains were analyzed by IS
6110
restriction fragment length polymorphism, antibiotic susceptibility tests, spoligotyping, reverse hybridization to regions of the
rpoB
gene, and sequencing of the
katG
gene. Epidemiological links between the patients were mapped, and the strains were compared to those isolated in 36 other countries and regions. All strains were resistant to isoniazid and carried Ala234Gly, Ser315Thr, and Arg463Leu substitutions in the
katG
gene. Eleven strains were MDR and carried a Ser531Leu substitution in the
rpoB
gene. MDR was acquired in the index patient after arrival in Norway. Links were found among 14 patients. The strain was imported from Somalia but acquired MDR and was transmitted in Norway. This demonstrated that MDR strains are not necessarily imported from high-incidence countries and can be highly communicable. The outbreak underscores a deficiency in the TB control measures employed in many countries and challenges the adequacy of the policy of screening immigrants for TB only on arrival.
All-cause mortality among breast cancer patients in a screening trial: support for breast cancer mortality as an end point
Authors: Tabar L. , Duffy S.W. , Yen M-F. , Warwick J. , Vitak B. , Chen H-H. , Smith R.A.
Published: January 2003

BACKGROUND: It has recently been suggested that all-cause mortality is a more appropriate end point than disease specific mortality in cancer screening trials, and that disease specific mortality is biased in favour of screening. This suggestion is based partly on supposed inconsistencies between all-cause mortality results and disease specific results in cancer screening trials, and alleged increases in deaths from causes other than breast cancer among breast cancer cases diagnosed among women invited to screening. METHODS: We used data from the Swedish Two-County Trial of mammographic screening for breast cancer, in which 77 080 women were randomised to an invitation to screening and 55 985 to no invitation. We estimated relative risks (RRs) (invited v control) of death from breast cancer, death from other causes within the breast cancer cases, and death from all causes within the breast cancer cases. RRs were adjusted for age and took account of the longer follow up of breast cancer cases in the invited group due to lead time. RESULTS: There was a significant 31% reduction in breast cancer mortality in the invited group (RR 0.69, 95% confidence interval (CI) 0.58–0.80; p<0.001). There was no significant increase in deaths from other causes among breast cancer cases in the invited group (RR 1.12, 95% CI 0.96–1.31; p=0.14). A significant 19% reduction in deaths from all causes was observed among breast cancer cases in the group invited to screening (RR 0.81, 95% CI 0.72–0.90; p<0.001). A more conservative estimation gave a significant 13% reduction (RR 0.87, 95% CI 0.78–0.97; p=0.01). These findings are consistent with the magnitude of the reduction in breast cancer mortality. CONCLUSIONS: Invitation to screening was associated with a reduction in deaths from all causes among breast cancer cases, consistent with high participation rates in screening. There is no significant evidence of bias in cause of death classification in the Two-County Trial, and as breast cancer mortality is the targeted clinical outcome in breast cancer screening, it is the appropriate end point in a breast cancer screening trial. All-cause mortality is a poor and inefficient surrogate for breast cancer mortality.
Reconstructing ecosystem dynamics in the central Pacific Ocean, 19521998. II. A preliminary assessment of the trophic impacts of fishing and effects on tuna dynamics
Authors: Cox Sean P , Essington Timothy E , Kitchell James F , Martell Steven J.D. , Walters Carl J , Boggs Christofer , Kaplan Isaac
Published: January 2003

Pelagic fisheries in the Pacific Ocean target both large (Thunnus spp.) and small tunas (juveniles of Thunnus spp; Katsuwonus pelamis) but also take billfishes (Xiphias gladius, Makaira spp., Tetrapturus spp., Istiophorus platypterus) and sharks (Prionace glauca, Alopias superciliosus, Isurus oxyrinchus, Carcharhinus longimanus, Galeocerdo cuvieri) as bycatch. We developed a multispecies model using the Ecopath with Ecosim software that incorporated time-series estimates of biomass, fishing mortality, and bycatch rates (19521998) to evaluate the relative contributions of fishing and trophic impacts on tuna dynamics in the central Pacific (0°N to 40°N and 130°E to 150°W). The Ecosim model reproduced the observed trends in abundance indices and biomass estimates for most large tunas and billfishes. A decline in predation mortality owing to depletion of large predators was greatest for small yellowfin tuna and could possibly account for apparent increases in biomass. For other tunas, however, predicted changes in predation mortality rates were small (small bigeye) or were overwhelmed by much larger increases in fishing mortality (skipjack and small albacore). Limited evidence of trophic impacts associated with declining apex predator abundance likely results from the difficulties of applying detailed trophic models to open ocean systems in which ecological and fishery data uncertainties are large.
Key principles for understanding fish bycatch discard mortality
Authors: Davis Michael W
Published: January 2003

The mortality of discarded fish bycatch is an important issue in fisheries management and, because it is generally unmeasured, represents a large source of uncertainty in estimates of fishing mortality worldwide. Development of accurate measures of discard mortality requires fundamental knowledge, based on principles of bycatch stressor action, of why discarded fish die. To date, discard mortality studies in the field have focused on capture stressors. Recent laboratory discard experiments have demonstrated the significant role of environmental factors, size- and species-related sensitivity to stressors, and interactions of stressors, which increase mortality. In addition, delayed mortality was an important consideration in experimental design. The discard mortality problem is best addressed through a combination of laboratory investigation of classes of bycatch stressors to develop knowledge of key principles of bycatch stressor action and field experiments under realistic fishing conditions to verify our understanding and make predictions of discard mortality. This article makes the case for a broader ecological perspective on discard mortality that includes a suite of environmental and biological factors that may interact with capture stressors to increase stress and mortality.
Energetic costs of migration through the Fraser River Canyon, British Columbia, in adult pink (Oncorhynchus gorbuscha) and sockeye (Oncorhynchus nerka) salmon as assessed by EMG telemetry
Authors: Standen Emily M , Hinch Scott G , Healey Michael C , Farrell Anthony P
Published: January 2003

Adult Pacific salmon (Oncorhynchus spp.) depend on energy reserves to complete their upriver spawning migration. Little is known about how flow patterns and bank characteristics affect energetics or how species differ in reach-specific energy use. In 1999, electromyogram (EMG) radiotelemetry was used to describe activity levels and estimate energy use of 12 adult pink salmon (Oncorhynchus gorbuscha) during their upstream migration in a 7-km section of the Fraser River Canyon. Data collected previously on sockeye salmon (Oncorhynchus nerka) in the same study area provided a species comparison. We could not identify any strong differences in energetics between species. Although sex had some influence, reach characteristics were the primary factors affecting migration activity and energetics. Fish increased their activity levels when they migrated through reaches constricted by islands or gravel bars compared with nonconstricted reaches. The former contained higher velocity currents and more complex hydraulic conditions than the latter. Two behavioural responses, with similar energetic consequences, occurred in constricted reaches. Either fish swam slowly and took more time, presumably searching for lower velocity areas for migration thus increasing passage time, or they swam quickly through higher velocity flow fields.
The millipeds of central Canada (Arthropoda: Diplopoda), with reviews of the Canadian fauna and diplopod faunistic studies
Authors: Shelley Rowland M
Published: January 2003

The milliped fauna of central Canada, extending from the Rocky Mountains of Alberta to James Bay and eastern Lake Superior, Ontario, comprises nine species, four Palearctic introductions, Cylindroiulus latestriatus (Curtis), Archiboreoiulus pallidus (Brade-Birks), Nopoiulus kochii (Gervais), and Polydesmus inconstans Latzel, and five native species, Aniulus garius (Chamberlin), Oriulus venustus (Wood), Underwoodia iuloides (Harger), Underwoodia tida Chamberlin, and Brunsonia albertana (Chamberlin). Three additional species, Polyxenus lagurus (L.), Aniulus (Hakiulus)diversifrons diversifrons (Wood), and Oxidus gracilis (C.L. Koch), are potential inhabitants. Aniulus garius is newly recorded from Alberta, Saskatchewan, and Manitoba, and Archiboreoiulus pallidus is newly reported from British Columbia and Illinois, U.S.A.; Zygotyla phana Chamberlin is formally placed in synonymy under Brunsonia atrolineata (Bollman). The total Canadian fauna consists of 6 orders, 20 families, 43 genera, and 62 species/subspecies, nearly one-third of which (20 species in total) are importations from the Palearctic and Asiatic realms. The total indigenous fauna therefore comprises 6 orders, 15 families, 30 genera, and 42 species, and 10 additional species potentially occur in British Columbia, Ontario, Quebec, and New Brunswick. Uroblaniulus idahoanus (Chamberlin) is provisionally recognized as the representative of the tribe Uroblaniulini (Julida: Parajulidae) in British Columbia, and specific localities are reported, which also constitute new records for the province and country. Canada is the first large country in the world whose diplopod fauna is essentially completely known; other countries, islands, and island groups in this category are summarized.
The influence of adaptation of rumen microflora on in vitro digestion of different forages by sheep and red deer
Authors: Gordon Iain J , Pérez-Barbería F Javier , Cuartas Paloma
Published: January 2003

The rumen microflora ecosystem adapts to the diet consumed by the animal. We tested the extent to which this adaptation facilitates or retards the digestion of plant-based forages. Following adaptation of sheep (Ovis aries) and red deer (Cervus elaphus) to diets containing different mixtures of alfalfa, grass, and heather (a dwarf shrub), an in vitro digestion technique was used to compare the ability of the rumen microflora to digest the mixtures of substrates to which they were adapted with their ability to digest different mixtures of the same substrates. In vitro digestion of different substrates was slightly greater in rumen liquor derived from sheep than in that derived from red deer for each of the different substrates, but the effect was not significant. Digestibility in sheep was independent of how the feed was presented (diet of equal proportions of alfalfa, grass, and heather in each meal (D-EQ): mean in vitro digestibility = 37.3%; alfalfa, grass, and heather presented sequentially on different days (D-SEQ): mean in vitro digestibility = 37.7%, SE of differences = 1.30%, p > 0.05). However, in red deer there was a significant effect of method of diet presentation (D-EQ: mean in vitro digestibility = 36.9%; D-SEQ: mean in vitro digestibility = 34.2%, SE of differences = 1.30%, p < 0.05), digestibility being substantially lower for D-SEQ than for D-EQ. Overall, the results demonstrated that whilst there were no species-specific differences in overall digestion efficiency, dietary adaptation had an effect on substrate digestion efficiency, with rumen microbes adapted to high-quality diets digesting these more efficiently than low-quality diets.
IMPROVED LIMITS ON PHOTON VELOCITY OSCILLATIONS
Authors: DE ANGELIS ALESSANDRO , PAIN REYNALD
Published: January 2003

The mixing of the photon with a hypothetical sterile paraphotonic state would have consequences on the cosmological propagation of photons. The absence of distortions in the optical spectrum of distant Type Ia supernovae allows to extend by two orders of magnitude the previous limit on the Lorentz-violating parameter δ associated to the photon–paraphoton transition, extracted from the absence of distortions in the spectrum of the cosmic microwave background. The new limit is consistent with the interpretation of the dimming of distant Type Ia supernovae as a consequence of a nonzero cosmological constant. Observations of gamma-rays from active galactic nuclei allow to further extend the limit on δ.
NEW VISTAS IN BRANEWORLD COSMOLOGY
Authors: SAHNI VARUN , SHTANOV YURI
Published: January 2003

Traditionally, higher-dimensional cosmological models have sought to provide a description of the fundamental forces in terms of a unifying geometrical construction. In this essay we discuss how, in their present incarnation, higher-dimensional "braneworld" models might provide answers to a number of cosmological puzzles including the issue of dark energy and the nature of the big bang singularity.
MISSING MASS AND THE ACCELERATION OF THE UNIVERSE: IS QUINTESSENCE THE ONLY EXPLANATION?
Authors: BAYIN SELÇUK Ş.
Published: January 2003

Detailed observations of the temperature fluctuations in the microwave background radiation indicate that we live in an open universe. From the size of these fluctuations, it is concluded that the geometry of the universe is quite close to Euclidean. In terms Friedmann models, this implies a mass density within 10% of the critical density required for a flat universe. Observed mass can only account for 30% of this mass density. Recently, an outstanding observation revealed that cosmos is accelerating. This motivated some astronomers to explain the missing 70% as some exotic dark energy called quintessence. In this essay, we present an alternative explanation to these cosmological issues in terms of the Friedmann Thermodynamics. This model has the capability of making definite predictions about the geometry of the universe, the missing mass problem, and the acceleration of the universe in-line with the recent findings. For future observations, we also predict where this model will start differing from the quintessence models.
CONFORMAL COUPLING'S OUTRAGEOUS LEGACY
Authors: RAUL ABRAMO L. , BRENIG LEON , GUNZIG EDGARD
Published: January 2003

In Einstein's gravity, non-minimal coupling of a scalar field to the scalar curvature leads to a paradoxical situation. On the one hand, it opens the way to qualitatively new cosmological dynamics. On the other hand, there are sectors of non-minimally coupled scalar-gravity theories for which the Einstein–Hilbert action reverses its sign, which seems to indicate that the whole system is unstable. We show how conformal coupling bypasses this problem. Due to a subtle interplay between gravity and the scalar field, classical and quantum stability are guaranteed globally. This liberates conformal coupling from a serious obstacle. Inflationary solutions in the new sector are also presented, which are validated by current observations.
CAN A BLACK HOLE BE USED AS A PORTAL TO OTHER UNIVERSES?
Authors: BURKO LIOR M.
Published: January 2003

We study numerically the evolution of space-time inside a black hole under perturbations of non-compact support. Using a very simplified toy model of a spherical charged black hole which is perturbed nonlinearly by a self-gravitating, spherical scalar field, we find that a portion of the Cauchy horizon survives as a non-central, null singularity.
BRANE-WORLD COSMOLOGY
Authors: COLEY A. A.
Published: January 2003

It is argued that typically the initial singularity is isotropic in brane world cosmological models. Consequently brane cosmology naturally gives rise to a set of initial data that provide the conditions for inflation to subsequently take place, leading to a self-consistent and viable cosmological scenario.
INFLATIONARY SCENARIO IN BRANS–DICKE THEORY FOR BIANCHI VI0 SPACE–TIME MODEL
Authors: CHAKRABORTY SUBENOY , GHOSH ARABINDA
Published: January 2003

We have investigated perfect fluid model in Brans–Dicke theory for Bianchi VI 0 space–time and have obtained exact analytical solutions considering barotropic equation of state. These solutions have been analyzed for different values of the parameters involved and some of them have shown a period of exponential expansion.
EFFECT OF CORIOLIS FORCE ON ACCRETION FLOWS AROUND ROTATING COMPACT OBJECT
Authors: PRASANNA A. R. , MUKHOPADHYAY BANIBRATA
Published: January 2003

Using the generalised set of fluid equations that include the "Coriolis force" along with the centrifugal and pressure gradient forces, we have reanalysed the class of self-similar solutions, with the pseudo-Newtonian potential. We find that the class of solutions is well behaved for almost the entire parameter space except for a few selected combinations of γ and α for the co-rotating flow. The analysis of the Bernoulli number shows that whereas it remains positive for co-rotating flow for f > 1/3, for the counter-rotating flow it does admit both positive and negative values, indicating the possibility of energy transfer in either direction.
ON PERIOD AND BURST HISTORIES OF AXPs AND SGRs AND THE POSSIBLE EVOLUTION OF THESE OBJECTS ON THE $P -\dot P$ DIAGRAM
Authors: GUSEINOV OKTAY H. , YAZGAN EFE , ANKAY AŞKIN , TAGIEVA SEVINÇ
Published: January 2003

In this paper, timing data for anomalous X-ray pulsars and soft gamma repeaters are compiled. Timing properties of these objects are investigated. The effect of bursts of soft gamma repeaters on their period history is investigated. The [Formula: see text] diagram for pulsars, X-ray binaries, anomalous X-ray pulsars, soft gamma repeaters and dim radio quiet neutron stars is constructed. The possible evolutionary tracks for anomalous X-ray pulsars, soft gamma repeaters and dim radio quiet neutron stars are examined.
DENSITY CONTRAST-PECULIAR VELOCITY RELATION IN THE NEWTONIAN GAUGE
Authors: RAHVAR SOHRAB
Published: January 2003

We investigate relation between density contrast and peculiar velocity in the Newtonian gauge, in general relativistic framework of theory of large scale structure formation in the universe. According to the gauge-invariant property of the energy-momentum tensor in this gauge, the velocity perturbation behaves like the Newtonian peculiar velocity. In this framework, the relation between peculiar velocity and density contrast with respect to the Newtonian–Peebles formula has an extra correction term which is ignorable for the small scale structures. The relativistic correction of peculiar velocity for structures of the extent of hundred mega parsec is about few percents which is smaller than the accuracy of the recent peculiar velocity measurements. We also study CMB anisotropies due to the Doppler effect in the Newtonian gauge compared with those obtained using Newtonian gravity.
EROS/MACHO GRAVITATIONAL MICROLENSING EVENTS TOWARD LMC IN EVANS HALO MODEL
Authors: RAHVAR SOHRAB
Published: January 2003

After a decade of gravitational microlensing experiments, 13 to 17 events MACHO group (depending on quality) and two events by EROS have been detected. All of those have been observed in the direction of Large Magellanic Cloud. We use Evans spherically symmetric halo model to study the rate of microlensing events. The expected number of events in this models obtained using EROS and MACHO observational efficiencies. We compare our numbers with the observed events to obtain the fraction of halo that is made by compact objects. It is shown that results derived from the two experiments are in good agreement with each other and MACHOs comprise only a fraction (depending on the model) of Milky Way halo. The results are also compatible with the White Dwarfs population studies in the Hubble Deep Field.
THE RELATIVISTIC IRON Kα LINE FROM AN ACCRETION DISC ONTO A STATIC NON-BARYONIC COMPACT OBJECT
Authors: LU YOUJUN , TORRES DIEGO F.
Published: January 2003

This paper continues the study of the properties of an accretion disc rotating around a non-baryonic (assumed super-massive) compact object. This kind of objects, generically known as boson stars, were earlier proposed as a possible alternative scenario to the existence of super-masive black holes in the center of every galaxy. A dilute boson star has also been proposed as a large part of the non-baryonic dark matter, flattening galactic rotational velocities curves. In this contribution, we compute the profile of the emission lines of Iron; its shape has been for long known as a useful diagnosis of the space-time geometry. We compare with the case of a Schwarzschild black hole, concluding that the differences are observationally distinguishable.
QUANTUM MULTIPOLE NOISE AND GENERALIZED QUANTUM STOCHASTIC EQUATIONS
Authors: PECHEN A. N. , VOLOVICH I. V.
Published: January 2003

A notion of quantum multipole (in particular, dipole) noise is considered. Quantum dipole noise is an analogue of quantum white noise but it acts in a Fock space with indefinite metric. Quantum white noise describes the leading term in the stochastic limit approximation to quantum dynamics while quantum multipole noise describes the corrections to the leading term. We obtain and study the generalized quantum stochastic equations describing corrections to the stochastic limit which include quantum dipole noise.
Current Use of Unopposed Estrogen and Estrogen Plus Progestin and the Risk of Acute Myocardial Infarction Among Women With Diabetes
Authors: Ferrara Assiamira , Quesenberry Charles P. , Karter Andrew J. , Njoroge Catherine W. , Jacobson Alice S. , Selby Joseph V.
Published: January 2003

Background—

Little is known about hormone replacement therapy (HRT) and risk for myocardial infarction (MI) in diabetic women. We examined associations of current HRT, estrogen dosage, and time since HRT initiation with risk of acute MI in diabetic women.

Methods and Results—

Cox proportional hazards models, with current HRT modeled as a time-dependent covariate, were used to assess the 3-year risk of MI. Among 24 420 women without a recent MI (mean age 64.9 years), 1110 incident MIs were identified. After adjustment for cardiovascular risk factors, current HRT was associated with reduced MI risk (relative hazard [RH] 0.84, 95% CI 0.72 to 0.98). The RH for MI associated with current estrogen plus progestin use was 0.77 (95% CI 0.61 to 0.97), and the RH for MI associated with current unopposed estrogen use was 0.88 (95% CI 0.73 to 1.05). Women were at reduced MI risk if they were taking a low or medium dose of estrogen (equivalent to <0.625 or 0.625 mg of conjugated estrogen, respectively) but not a high dose (>0.625 mg of conjugated estrogen or its equivalent). Among those whose current use of HRT was <1 year, the RH for MI was 1.03 (95% CI 0.74 to 1.44), whereas among users for ≥1 year, the RH was 0.81 (95% CI 0.66 to 1.00). Among 580 women with a recent MI (mean age 69.2 years), 89 recurrent MIs were identified. An increased risk of recurrent MI was observed among current HRT users (RH 1.78, 95% CI 1.06 to 2.98), which was higher among those with current use for <1 year (RH 3.84, 95% CI 1.60 to 9.20).

Conclusions—

In women without a recent MI, use of estrogen plus progestin was associated with decreased risk of MI. However, HRT was associated with increased risk of MI in women with history of a recent MI. Data from clinical trials in diabetic women are needed.
Fluvastatin Enhances the Inhibitory Effects of a Selective Angiotensin II Type 1 Receptor Blocker, Valsartan, on Vascular Neointimal Formation
Authors: Horiuchi Masatsugu , Cui Tai-Xing , Li Zhen , Li Jian-Mei , Nakagami Hironori , Iwai Masaru
Published: January 2003

Background—

The present studies were undertaken to investigate the potential effect of a hydroxymethylglutaryl coenzyme A reductase inhibitor (statin) to enhance the inhibitory effect of an angiotensin (Ang) II type 1 (AT
1
) receptor blocker (ARB) on vascular neointimal formation and to explore the cellular mechanism of cross-talk of the AT
1
receptor and statin in vascular smooth muscle cells (VSMCs).

Methods and Results—

Neointimal formation and the proliferation of VSMCs induced by cuff placement around the femoral artery were significantly inhibited by treatment with an ARB, valsartan, at a dose of 0.1 mg · kg
−1
· d
−1
and with fluvastatin at a dose of 1 mg · kg
−1
· d
−1
, which did not influence mean arterial blood pressure or plasma cholesterol level, whereas valsartan or fluvastatin alone at these doses did not affect neointimal formation or the proliferation of VSMCs. Pretreatment with fluvastatin (≈5 μmol/L) for 24 hours significantly inhibited Ang II (1 μmol/L)–mediated DNA synthesis and
c-fos
promoter activity in cultured VSMCs. Moreover, pretreatment of VSMCs with fluvastatin significantly inhibited Ang II–mediated extracellular signal-regulated kinase (ERK) activation and tyrosine- and serine-phosphorylation of signal transducer and activator of transcription (STAT)1 and STAT3. AT
1
receptor–mediated recruitment of Rac-1 to Janus kinase (Jak) family/STATs was also inhibited by fluvastatin. Consistent with these in vitro results, phosphorylation of ERK, STAT1, and STAT3 was attenuated by the coadministration of valsartan and fluvastatin even at low doses in vivo.

Conclusion—

These results suggest that the cholesterol-independent inhibition of AT
1
receptor–mediated VSMC proliferation by statins may contribute to the beneficial effects of statins combined with an ARB on vascular diseases.