bluuebunny/crossref_metadata_2025_split huggingface dataset:
Distribution of
Streptococcus pneumoniae
Serotypes Responsible for Penicillin Resistance and the Potential Role of New Conjugate Vaccines in New Caledonia
Authors: Michel N. , Watson M. , Baumann F. , Perolat P. , Garin B. 
Published: December 2005

ABSTRACT

Invasive pneumococcal disease is a significant cause of morbidity and mortality worldwide. The aim of this study was to establish the serotypes responsible for pneumococcal disease and the serotypes responsible for penicillin resistance in Noumea, New Caledonia. Isolates of
Streptococcus pneumoniae
from all body sites referred to the Microbiology Department of the Pasteur Institute in New Caledonia between May 1999 and May 2001 had serotyping and susceptibility testing performed. Basic demographic data on patients were also collected. A total of 298 isolates were included in the study. The most common serotypes were types 1 (20%), 23F (10%), 12F (8%), 19F (8%), and 6B (5%). The serotype distribution differed significantly with age, site of collection, and ethnicity. Overall, 280 of 298 (94%) of the isolates had serogroups that are included in the 23-valent vaccine. However, only 14 of 20 (70%) of the isolates associated with invasive disease from children younger than 5 years of age and 26 of 113 (23%) of invasive isolates from patients more than 5 years of age were included in the new 7-valent conjugate vaccine. Overall, reduced susceptibility to penicillin was found in 43 of 298 (14.4%) of the isolates, with 13% falling into the intermediate resistance category and only 5 (2%) being high-level resistant. A higher prevalence of penicillin resistance occurred in younger age groups and in European patients and involved specifically certain serotypes. The 7-valent conjugate pneumococcal vaccine has potential benefit for the New Caledonian population under 5 years of age and should be considered for future vaccines schedules.
Use of Ramification Amplification Assay for Detection of
Escherichia coli
O157:H7 and Other
E. coli
Shiga Toxin-Producing Strains
Authors: Li Fan , Zhao Chunyan , Zhang Wandi , Cui Shenghui , Meng Jianghong , Wu Josephine , Zhang David Y. 
Published: December 2005

ABSTRACT

Escherichia coli
O157:H7 and other Shiga toxin-producing
E. coli
(STEC) strains are important human pathogens that are mainly transmitted through the food chain. These pathogens have a low infectious dose and may cause life-threatening illnesses. However, detection of this microorganism in contaminated food or a patient's stool specimens presents a diagnostic challenge because of the low copy number in the sample. Often, a more sensitive nucleic acid amplification method, such as PCR, is required for rapid detection of this microorganism. Ramification amplification (RAM) is a recently introduced isothermal DNA amplification technique that utilizes a circular probe for target detection and achieves exponential amplification through the mechanism of primer extension, strand displacement, and ramification. In this study, we synthesized a circular probe specific for the Shiga toxin 2 gene (
stx
2
). Our results showed that as few as 10 copies of
stx
2
could be detected, indicating that the RAM assay was as sensitive as conventional PCR. We further tested 33 isolates of
E coli
O157:H7, STEC,
Shigella dysenteriae
, and nonpathogenic
E. coli
by RAM assay. Results showed that all 27 STEC isolates containing the
stx
2
gene were identified by RAM assay, while
S. dysenteriae
and nonpathogenic
E. coli
isolates were undetected. The RAM results were 100% in concordance with those of PCR. Because of its simplicity and isothermal amplification, the RAM assay could be a useful method for detecting STEC in food and human specimens.
Association of Virulence Genotype with Phylogenetic Background in Comparison to Different Seropathotypes of Shiga Toxin-Producing
Escherichia coli
Isolates
Authors: Girardeau Jean Pierre , Dalmasso Alessandra , Bertin Yolande , Ducrot Christian , Bord Séverine , Livrelli Valérie , Vernozy-Rozand Christine , Martin Christine 
Published: December 2005

ABSTRACT

The distribution of virulent factors (VFs) in 287 Shiga toxin-producing
Escherichia coli
(STEC) strains that were classified according to Karmali et al. into five seropathotypes (M. A. Karmali, M. Mascarenhas, S. Shen, K. Ziebell, S. Johnson, R. Reid-Smith, J. Isaac-Renton, C. Clark, K. Rahn, and J. B. Kaper, J. Clin. Microbiol. 41:4930-4940, 2003) was
investigated. The associations of VFs with phylogenetic background were
assessed among the strains in comparison with the different
seropathotypes. The phylogenetic analysis showed that STEC strains
segregated mainly in phylogenetic group B1 (70%) and revealed the
substantial prevalence (19%) of STEC belonging to phylogenetic group A
(designated STEC-A). The presence of virulent clonal groups in
seropathotypes that are associated with disease and their absence from
seropathotypes that are not associated with disease support the concept
of seropathotype classification. Although certain VFs (
eae
,
stx
2-EDL933
,
stx
2-vha
, and
stx
2-vhb
) were concentrated in seropathotypes
associated with disease, others (
astA
, HPI,
stx
1c
, and
stx
2-NV206
)
were concentrated in seropathotypes that are not associated with
disease. Taken together with the observation that the STEC-A group was
exclusively composed of strains lacking
eae
recovered from
seropathotypes that are not associated with disease, the“
atypical” virulence pattern suggests that STEC-A
strains comprise a distinct category of STEC strains. A practical
benefit of our phylogenetic analysis of STEC strains is that
phylogenetic group A status appears to be highly predictive of“
nonvirulent”
seropathotypes.
Noroviruses as a Cause of Traveler's Diarrhea among Students from the United States Visiting Mexico
Authors: Ko GwangPyo , Garcia Coralith , Jiang Zhi-Dong , Okhuysen Pablo C. , Belkind-Gerson Jaime , Glass Roger I. , DuPont Herbert L. 
Published: December 2005

ABSTRACT

Stool specimens from 124 international travelers with acute diarrhea were tested for the presence of enteropathogens. Noroviruses (NoVs) were the second most commonly identified enteric pathogen in diarrheal stool samples (21/124, 17%), exceeded only by enterotoxigenic
Escherichia coli
(50/106, 47%). This study indicates that NoV is an underappreciated cause of traveler's diarrhea.
Multiplex PCR Assay That Identifies the Major Lipooligosaccharide Serotype Expressed by
Moraxella catarrhalis
Clinical Isolates
Authors: Edwards Katie J. , Schwingel Johanna M. , Datta Anup K. , Campagnari Anthony A. 
Published: December 2005

ABSTRACT

A heterologous cluster of glycosyltransferase genes was identified in the three
Moraxella catarrhalis
LOS serotype strains. Multiple PCR primers designed to this region amplified products that differentiate between the serotypes more rapidly and efficiently than previously described serological analyses. This assay will be valuable for clinical and research-based studies.
Evaluation of Ribotyping as a Tool for Molecular Typing of
Yersinia pseudotuberculosis
Strains of Worldwide Origin
Authors: Voskressenskaya Ekaterina , Leclercq Alexandre , Tseneva Galina , Carniel Elisabeth 
Published: December 2005

ABSTRACT

Yersinia pseudotuberculosis
is a gram-negative bacterium that infects a wide range of animals, including humans, and is transmitted by the fecal-oral route. This species is found globally and is responsible for human outbreaks, mainly in cold countries. The aim of this study was to evaluate the potential of ribotyping for the molecular typing of worldwide isolates. For this purpose, 80 strains of
Y. pseudotuberculosis
belonging to the six classical serotypes and nine subserotypes and isolated from various countries and different hosts were analyzed. Combination of the EcoRI and EcoRV ribopatterns allowed the delineation of 27 ribotypes. In most instances, ribotypes were associated with specific subserotypes and allowed their subdivision. No association between the ribotype and the geographical origin of the strains was observed, arguing for a global spread of this organism. Similarly, no marked association between the ribotype and the type of host was noted, confirming the circulation of this pathogen in the environment, different animal species, and human hosts.
Y. pseudotuberculosis
exhibited ribopatterns very close to those of
Y. pestis
, although not completely identical. Altogether, the present study demonstrates that ribotyping may be a useful tool for molecular typing of global isolates of
Y. pseudotuberculosis
but that it has some limitations due to the small number of hybridizing bands that generate the diversity of the profiles.
Genetic Relationship between Human and Animal Isolates ofCandida albicans
Authors: Edelmann Anke , Krüger Monika , Schmid Jan 
Published: December 2005

ABSTRACTAnalyzingCandida albicansisolates from different human and animal individuals by Ca3 fingerprinting, we obtained no evidence for host-specific genotypes and for the existence of species-specific lineages, even though a certain degree of separation between human and animal isolates was found. Therefore, animals could potentially serve as reservoirs for humanCandidainfection.
Use of Microelectronic Array Technology for Rapid Identification of Clinically Relevant Mycobacteria
Authors: Sanguinetti Maurizio , Novarese Linda , Posteraro Brunella , Ranno Stefania , De Carolis Elena , Pecorini Giovanni , Lucignano Barbara , Ardito Fausta , Fadda Giovanni 
Published: December 2005

ABSTRACT
We developed a new method based on the Nanochip microelectronic array technology for identification of various clinically relevant mycobacterial species. PCR-amplified rRNA genes obtained from 270 positive Mycobacteria Growth Indicator Tube cultures were successfully tested by hybridizing them with species-selective probes, and the results agreed with those of conventional identification methods. The system is rapid and accurate and opens new perspectives in clinical diagnostics.
PCR Protocol for Specific Identification of
Candida nivariensis
, a Recently Described Pathogenic Yeast
Authors: Alcoba-Flórez Julia , del Pilar Arévalo María , González-Paredes F. Javier , Cano Josep , Guarro Josep , Pérez-Roth Eduardo , Méndez-Álvarez Sebastián 
Published: December 2005

ABSTRACT

Candida nivariensis
is a recently described pathogenic yeast closely related to
Candida glabrata
. We developed a specific set of oligonucleotide primers based on the internal transcribed spacer regions of the rRNA gene for the rapid identification of
C. nivariensis.
PCR with these primers amplified a 206-bp amplicon from
C. nivariensis.
Comparison of the Avidity Index Method and the Serologic Testing Algorithm for Recent Human Immunodeficiency Virus (HIV) Seroconversion, Two Methods Using a Single Serum Sample for Identification of Recent HIV Infections
Authors: Martró Elisa , Suligoi Barbara , González Victoria , Bossi Vincenzo , Esteve Anna , Mei Joanne , Ausina Vicenç 
Published: December 2005

ABSTRACT
A study was designed to compare an avidity index method to the serologic testing algorithm for recent human immunodeficiency virus (HIV) seroconversion (STARHS) for the detection of recent HIV infection. One hundred sixty HIV-positive sera were tested. Both techniques performed similarly in identifying recent infections, although STARHS tended to misclassify more individuals that had long-standing infection as being recently infected.
Phenotypic and functional profiling of human proinflammatory type-1 and anti-inflammatory type-2 macrophages in response to microbial antigens and IFN-γ- and CD40L-mediated costimulation
Authors: Verreck Frank A W , de Boer Tjitske , Langenberg Dennis M L , van der Zanden Linda , Ottenhoff Tom H M 
Published: December 2005

Abstract
Macrophages (Mφ) comprise a heterogeneous population of cells with various immune and homeostatic functions. Recently, we have described type-1 and type-2 human monocyte-derived Mφ subsets. Although both support outgrowth of intracellular mycobacteria, Mφ-1 secretes interleukin (IL)-23/IL-12 and supports T helper cell type 1 (Th1) responses, whereas Mφ-2 fails to produce IL-23/IL-12, predominantly secretes IL-10, and inhibits Th1 function. Here, we further describe the phenotypic and functional profiles of Mφ-1 and Mφ-2 in response to microbial antigens and interferon-γ (IFN-γ) and CD40L as costimulatory T cell back-talk signals. Activated IL-23+/IL-12+ Mφ-1 secreted IL-1β, IL-18, IL-6, and tumor necrosis factor-α (TNF-α), as well as IL-8, monocyte chemoattractant protein-1 (MCP-1), IFN-inducible protein 10 (IP-10), Mφ inflammatory protein-1β (MIP-1β), regulated on activation, normal T expressed and secreted (RANTES), Mφ-derived chemokine (MDC), and (low levels of) pulmonary and activation-regulated chemokine and thymus and activation-regulated chemokine (TARC), corroborating their proinflammatory function. Regardless of the stimulus, Mφ-2 maintained their IL-10+ signature cytokine profile and produced no or relatively low levels of IL-12p40, IL-1β, IL-6, TNF-α, MDC, or TARC. It is remarkable that Mφ-2 secreted high levels of IL-8, MCP-1, IP-10, MIP-1β, and RANTES, suggesting an active role for these cells in regulating cellular immunity and homeostasis. Mφ-1 and Mφ-2 expressed similar levels of Toll-like receptor and dendritic cell-specific intercellular adhesion molecule-3-grabbing nonintegrin as microbial pattern recognition receptors. Mφ-2, unlike Mφ-1 but like other nonclassical Mφ described previously, expressed CD163 and down-modulated human leukocyte antigen and costimulatory molecules specifically upon activation. These findings demonstrate how Mφ-1/Mφ-2 polarization can differentially skew the host response toward pro- or anti-inflammatory immune responses, respectively. This is likely to be relevant for host-pathogen interactions in chronic bacterial infections and provides a model for dissecting pro- and anti-inflammatory cascades.
Migratory monocytes and granulocytes are major lymphatic carriers of Salmonella from tissue to draining lymph node
Authors: Bonneau Michel , Epardaud Mathieu , Payot Fabrice , Niborski Violeta , Thoulouze Maria-Isabel , Bernex Florence , Charley Bernard , Riffault Sabine , Guilloteau Laurence A , Schwartz-Cornil Isabelle 
Published: December 2005

Abstract
Dendritic cells (DC) are recognized as sentinels, which capture antigens in tissue and migrate to the lymph node, where they initiate immune responses. However, when a vaccine strain of green fluorescent protein-expressing Salmonella abortusovis (SAO) was inoculated into sheep oral mucosa, it induced accumulation of myeloid non-DC in the subcapsular sinus and paracortex of the draining lymph node, and SAO was mainly found associated with these cells (granulocytes and macrophages) but rarely with DC. To analyze how bacteria reached lymph nodes, we used cervical pseudo-afferent lymph duct catheterization. We showed that Salmonella administered in the oral mucosa were traveling free in lymph or associated with cells, largely with lymph monocytes and granulocytes but less with DC. SAO also induced a strong influx of these phagocytic cells in afferent lymph. Migrating DC presented a semi-mature phenotype, and SAO administration did not alter their expression of major histocompatibility complex type 2 and coactivation molecules. Compared with blood counterparts, lymph monocytes expressed lower levels of CD40, and granulocytes expressed higher levels of CD80. The data suggest that immunity to bacteria may result from the complex interplay between a mixture of phagocytic cell types, which transport antigens and are massively recruited via lymph to decisional lymph nodes.
Identification of tyrosine residues crucial for CD200R-mediated inhibition of mast cell activation
Authors: Zhang Shuli , Phillips Joseph H 
Published: December 2005

Abstract
CD200 and its receptor CD200R are type-1 membrane glycoproteins, which contain two immunoglobulin-like domains. Engagement of CD200R by CD200 inhibits activation of myeloid cells. Unlike the majority of immune inhibitory receptors, CD200R does not contain an immunoreceptor tyrosine-based inhibitory motif but contains three tyrosine residues (Y286, Y289, and Y297) in the cytoplasmic domain. Y297 is located in an NPxY motif. Previously, we have shown that engagement of CD200R in mouse mast cells induces its tyrosine phosphorylation and recruitment of inhibitory adaptor proteins Dok1 and Dok2, leading to the inhibition of Ras/mitogen-activated protein kinase activation. In the present study, we examined the roles of these three tyrosines in CD200R-mediated inhibition by site-directed mutagenesis in mouse mast cells. Our data show that Y286 and Y297 are the major phosphorylation sites and are critical for CD200R-mediated inhibition of mast cell activation, and Y289 is dispensable. Our data also suggest that the Src family kinase may mediate the phosphorylation of CD200R and Dok.
Cyclin T1 but not cyclin T2a is induced by a post-transcriptional mechanism in PAMP-activated monocyte-derived macrophages
Authors: Liou Li-Ying , Haaland Richard E , Herrmann Christine H , Rice Andrew P 
Published: December 2005

Abstract
Positive transcription elongation factor b (P-TEFb) is an RNA polymerase II elongation factor which exists as multiple complexes in human cells. These complexes contain cyclin-dependent kinase 9 as the catalytic subunit and different cyclin subunits—cyclin T1, T2a, T2b, or K. Cyclin T1 is targeted by the human immunodeficiency virus (HIV) Tat protein to activate transcription of the HIV provirus. Expression of this P-TEFb subunit is highly regulated in monocyte-derived macrophages (MDMs). Cyclin T1 is induced early during differentiation and is shut off later by proteasome-mediated proteolysis. Cyclin T1 can be reinduced by pathogen-associated molecular patterns (PAMPs) or HIV infection. In this study, we analyzed regulation of P-TEFb in MDMs by examining 7SK small nuclear RNA and the HEXIM1 protein; these factors associate with P-TEFb and are thought to regulate its function. 7SK and HEXIM1 were induced early during differentiation, and this correlates with increased overall transcription. 7SK expression remained high, but HEXIM1 was shut off later during differentiation by proteasome-mediated proteolysis. Significantly, the cyclin T2a subunit of P-TEFb was not shut off during differentiation, and it was not induced by activation. Induction of cyclin T1 by PAMPs was found to be a slow process and did not involve an increase in cyclin T1 mRNA levels. Treatment of MDMs with PAMPs or a proteasome inhibitor induced cyclin T1 to a level equivalent to treatment with both agents together, suggesting that PAMPs and proteasome inhibitors act at a similar rate-limiting step. It is therefore likely that cyclin T1 induction by PAMPs is the result of a reduction in proteasome-mediated proteolysis.
HIV gp41-induced apoptosis is mediated by caspase-3-dependent mitochondrial depolarization, which is inhibited by HIV protease inhibitor nelfinavir
Authors: Garg Himanshu , Blumenthal Robert 
Published: December 2005

Abstract
Apoptotic loss of CD4+ T cells has been proposed as a mechanism of T cell depletion in human immunodeficiency virus (HIV) infections resulting in immunodeficiency. The Env glycoprotein has been implicated in apoptosis of uninfected bystander cells via gp120 binding to CD4/CXC chemokine receptor 4 as well as the fusion/hemifusion process mediated by gp41. Using an in vitro model of coculture of Env-expressing cells as effectors and CD4+ T cells as targets, we find that apoptosis mediated by Env glycoprotein in bystander cells in fact correlates with gp41-induced hemifusion. Further, the apoptotic pathway initiated by this interaction involves caspase-3-dependent mitochondrial depolarization and reactive oxygen species production. HIV gp41-induced mitochondrial depolarization is inhibited by protease inhibitor nelfinavir but not by other HIV protease inhibitors or inhibitors of calpain and cathepsin. This “kiss of death” (hemifusion) signaling pathway is independent of p38 mitogen-activated protein kinase and p53, making it distinct from the apoptosis seen in syncytia. We also show that virion-induced apoptosis is gp41-dependent. Our findings provide new insights into the mechanism via which HIV gp41 mediates apoptosis in bystander cells.
Identification of a phenotypically and functionally distinct population of long-lived neutrophils in a model of reverse endothelial migration
Authors: Buckley Christopher D , Ross Ewan A , McGettrick Helen M , Osborne Chloe E , Haworth Oliver , Schmutz Caroline , Stone Philip C W , Salmon Mike , Matharu Nick M , Vohra Rajiv K , Nash Gerard B , Rainger G Ed 
Published: December 2005

Abstract
Recent studies have demonstrated that neutrophils are not a homogenous population of cells. Here, we have identified a subset of human neutrophils with a distinct profile of cell-surface receptors [CD54high, CXC chemokine receptor 1low (CXCR1low)], which represent cells that have migrated through an endothelial monolayer and then re-emerged by reverse transmigration (RT). RT neutrophils, when in contact with endothelium, were rescued from apoptosis, demonstrate functional priming, and were rheologically distinct from neutrophils that had not undergone transendothelial migration. In vivo, 1–2% of peripheral blood neutrophils in patients with systemic inflammation exhibit a RT phenotype. A smaller population existed in healthy donors (≈0.25%). RT neutrophils were distinct from naïve circulatory neutrophils (CD54low, CXCR1high) and naïve cells after activation with formyl-Met-Leu-Phe (CD54low, CXCR1low). It is important that the RT phenotype (CD54high, CXCR1low) is also distinct from tissue-resident neutrophils (CD54low, CXCR1low). Our results demonstrate that neutrophils can migrate in a retrograde direction across endothelial cells and suggest that a population of tissue-experienced neutrophils with a distinct phenotype and function are present in the peripheral circulation in humans in vivo.
Multipopulation Analysis of Polymorphisms in Five Mononucleotide Repeats Used to Determine the Microsatellite Instability Status of Human Tumors
Authors: Buhard Olivier , Cattaneo Francesca , Wong Yick Fu , Yim So Fan , Friedman Eitan , Flejou Jean-François , Duval Alex , Hamelin Richard 
Published: December 2005

Purpose Human gastrointestinal tumors with inactivated DNA mismatch repair system (microsatellite instability [MSI] tumors) have distinct molecular and clinicopathologic profiles, and are associated with favorable prognosis. There is evidence suggesting that colorectal cancer patients with MSI tumors respond differently to adjuvant chemotherapy as compared with patients with non-MSI tumors. Finally, determination of the MSI status has clinical application for assisting in the diagnosis of suspected hereditary cases. It is thus becoming increasingly recognized that testing for MSI should be conducted systematically in all human cancers potentially of this type. We recently described a pentaplex polymerase chain reaction of five mononucleotide repeats to establish the MSI status of human tumors, and showed that this assay was 100% sensitive and specific. Moreover, these markers are quasimonomorphic in germline DNA of the white population (ie, individuals of Eurasian origin), and could be used for tumor MSI determination without the requirement for matching normal DNA in this group. Patients and Methods In this study, we analyzed a comparable panel of five mononucleotide markers in germline DNA from 1,206 individuals encompassing 55 different populations worldwide. Results With the exception of two Biaka Pygmies and one San individual for whom three markers showed variant alleles (three cases [0.2%]), the remaining 1,203 individuals showed no alleles of variant size (1,055 cases [87.5%]), or only one (122 cases [10.1%]) or two (26 cases [2.2%]) markers with variant alleles. All 60 MSI tumors investigated display instability in at least four of the five markers. Conclusion We demonstrated that tumor MSI status can be determined using the pentaplex reaction for all human populations without the need for matching normal DNA.