bluuebunny/crossref_metadata_2025_split huggingface dataset:
Absence of CTX-M Enzymes but High Prevalence of Clones, Including Clone ST131, among Fecal
Escherichia coli
Isolates from Healthy Subjects Living in the Area of Paris, France
Authors: Leflon-Guibout Véronique , Blanco Jorge , Amaqdouf Karim , Mora Azucena , Guize Louis , Nicolas-Chanoine Marie-Hélène 
Published: October 2008

ABSTRACT

Quinolone-resistant and CTX-M-15-producing
Escherichia coli
isolates belonging to clone ST131 have been reported in the community. This study was designed to identify these
E. coli
isolates in the stools of 332 independent healthy subjects living in the area of Paris, France. Stools were plated on media without antibiotics, in order to obtain the dominant (Dm) fecal
E. coli
strain, and with nalidixic acid (NAL) and cefotaxime. Quinolone susceptibility, phylogenetic groups, and molecular profiles, including multilocus sequence types (ST), were determined for all NAL-resistant (NAL-R) isolates. Groups were also determined for the Dm strains from participants with NAL-R isolates and from a subgroup without NAL-R isolates. All B2 isolates were typed; pulsed-field gel electrophoresis was performed for the ST131 isolates, and the results were compared with those for intercontinental clone ST131. Two participants (0.6%) had extended-spectrum β-lactamase-producing (SHV-2, TEM-52) fecal
E. coli
isolates, and 51 (15%) had NAL-R isolates; 51% of NAL-R isolates belonged to phylogenetic group A, 31% to group D, 16% to group B2, and 2% to group B1. The Dm strain was NAL-R in 3.3% of the 332 subjects. Forty-nine percent of the NAL-R isolates belonged to clones: ST10 and ST606 for group A isolates, ST117 and ST393 for group D isolates. Of all B2 isolates studied from 100 subjects (8 NAL-R strains; 19 NAL-susceptible dominant strains), 52% belonged to three clones: ST131 (
n
= 7), ST95 (
n
= 4), and ST141 (
n
= 3). This is the first study to show the presence of fecal
E. coli
isolates of clone ST131 in 7% of independent healthy subjects not colonized by CTX-M-15-producing isolates.
Transmission Classification Model To Determine Place and Time of Infection of Tuberculosis Cases in an Urban Area
Authors: de Vries G. , Baars H. W. M. , Šebek M. M. G. G. , van Hest N. A. H. , Richardus J. H. 
Published: October 2008

ABSTRACT
We conducted a population-based study in the Rotterdam region of The Netherlands to determine the place and time of infection of tuberculosis (TB) cases using conventional epidemiological and genotyping information. In particular, we focused on the extent of misclassification if genotyping was not combined with epidemiological information. Cases were divided into those with a unique mycobacterial DNA fingerprint, a clustering fingerprint, and an unknown fingerprint. We developed transmission classification trees for each category to determine whether patients were infected in a foreign country or recently (≤2 years) or remotely (>2 years) infected in The Netherlands. Of all TB cases during the 12-year study period, 38% were infected in a foreign country, 36% resulted from recent transmission in The Netherlands, and 18% resulted from remote infection in The Netherlands, while in the remaining cases (9%) either the time or place of infection could not be determined. The conventional epidemiological data suggested that at least 29% of clustered cases were not part of recent chains of transmission. Cases with unknown fingerprints, almost all culture negative, relatively frequently had confirmed epidemiological links with a recent pulmonary TB case in The Netherlands and were more often identified by contact tracing. Our findings highlight the idea that genotyping should be combined with conventional epidemiological investigation to establish the place and time of infection of TB cases as accurately as possible. A standardized way of classifying TB into recently, remotely, and foreign-acquired disease provides indicators for surveillance and TB control program performance that can be used to decide on interventions and allocation of resources.
Identification of Minimal Predictors of Avian Pathogenic
Escherichia coli
Virulence for Use as a Rapid Diagnostic Tool
Authors: Johnson Timothy J. , Wannemuehler Yvonne , Doetkott Curt , Johnson Sara J. , Rosenberger Sandra C. , Nolan Lisa K. 
Published: October 2008

ABSTRACT

To identify traits that predict avian pathogenic
Escherichia coli
(APEC) virulence, 124 avian
E. coli
isolates of known pathogenicity and serogroup were subjected to virulence genotyping and phylogenetic typing. The results were analyzed by multiple-correspondence analysis. From this analysis, five genes carried by plasmids were identified as being the most significantly associated with highly pathogenic APEC strains:
iutA
,
hlyF
,
iss
,
iroN
, and
ompT
. A multiplex PCR panel targeting these five genes was used to screen a collection of 994 avian
E. coli
isolates. APEC isolates were clearly distinguished from the avian fecal
E. coli
isolates by their possession of these genes, suggesting that this pentaplex panel has diagnostic applications and underscoring the close association between avian
E. coli
virulence and the possession of ColV plasmids. Also, the sharp demarcation between APEC isolates and avian fecal
E. coli
isolates in their plasmid-associated virulence gene content suggests that APEC isolates are well equipped for a pathogenic lifestyle, which is contrary to the widely held belief that most APEC isolates are opportunistic pathogens. Regardless, APEC isolates remain an important problem for poultry producers and a potential concern for public health professionals, as growing evidence suggests a possible role for APEC in human disease. Thus, the pentaplex panel described here may be useful in detecting APEC-like strains occurring in poultry production, along the food chain, and in human disease. This panel may be helpful toward clarifying potential roles of APEC in human disease, ascertaining the source of APEC in animal outbreaks, and identifying effective targets of avian colibacillosis control.
Aichi Virus, Norovirus, Astrovirus, Enterovirus, and Rotavirus Involved in Clinical Cases from a French Oyster-Related Gastroenteritis Outbreak
Authors: Le Guyader Françoise S. , Le Saux Jean-Claude , Ambert-Balay Katia , Krol Joanna , Serais Ophelie , Parnaudeau Sylvain , Giraudon Hélène , Delmas Gilles , Pommepuy Monique , Pothier Pierre , Atmar Robert L. 
Published: October 2008

ABSTRACT
Following a flooding event close to a shellfish production lagoon, 205 cases of gastroenteritis were linked to oyster consumption. Twelve stool samples from different individuals were collected. Analysis showed that eight samples were positive for multiple enteric viruses, and one stool sample had seven different enteric viruses. Analysis of shellfish implicated in the outbreak allowed detection of the same diversity of enteric viruses, with some viral genomic sequences being identical to those obtained from stool sample analysis. Shellfish were contaminated by as many as five different enteric viruses. For the first time in Europe, Aichi virus was identified in oyster samples. Shellfish samples collected over 3 weeks following the outbreak showed a progressive decline in the level of virus contamination as measured by the virus diversity detected and by quantitative reverse transcription-PCR.
Association of Tuberculous Endometritis with Infertility and Other Gynecological Complaints of Women in India
Authors: Kumar P. , Shah N. P. , Singhal A. , Chauhan D. S. , Katoch V. M. , Mittal S. , Kumar S. , Singh M. K. , Gupta S. Datta , Prasad H. K. 
Published: October 2008

ABSTRACT

Endometrial biopsy samples derived from 393 patients with assorted gynecological complaints were investigated for mycobacterial infection. By employment of four different techniques, mycobacterial pathogens were detected irrespective of the nature/type of clinical complaint.
Mycobacterium tuberculosis
was the predominant pathogen detected among the samples investigated.
Hepatitis and Human Bocavirus Primary Infection in a Child with T-Cell Deficiency
Authors: Kainulainen Leena , Waris Matti , Söderlund-Venermo Maria , Allander Tobias , Hedman Klaus , Ruuskanen Olli 
Published: October 2008

ABSTRACT
Human bocavirus (HBoV) is one of the recently identified respiratory viruses. The clinical features of HBoV infection have not yet been fully elucidated. We report an invasive HBoV infection and hepatitis in a boy with cartilage-hair hypoplasia and severe T-cell immunodeficiency.
Comparison of Classical Serotyping and PremiTest Assay for Routine Identification of Common
Salmonella enterica
Serovars
Authors: Wattiau Pierre , Van Hessche Mieke , Schlicker Christine , Vander Veken Heidi , Imberechts Hein 
Published: October 2008

ABSTRACT

The commercial PremiTest
Salmonella
kit uses a multiplexed DNA typing test aimed at identifying common serovars of
Salmonella enterica
. It was used in assays over a 9-month period in the Belgian reference laboratory that performs the routine identification of
Salmonella
strains of animal origin. A blind analysis of 754 strains was conducted in parallel by classical serotyping and the PremiTest assay. Full results were available for 685 strains (90.8%) by serotyping, while the remaining 69 strains were found to be nontypeable due to either a lack of surface antigen expression or autoagglutination properties. When the PremiTest assay (version 4.2) was performed with crude bacterial extracts, it identified 658 strains (87.3%), including most strains found to be nontypeable by serotyping. In contrast, it gave no, wrong, dual, or noninterpretable results for 96 strains, for which 23 were caused by assay failures. When purified DNA instead of crude extracts were tested, the number of strains successfully identified to the serovar level increased to 714 (94.7%), while all assay failures were cleared. Our conclusion is that, in its actual development stage, the application of the investigated kit to purified DNA samples offers a valuable alternative to classical serotyping for laboratories performing the routine identification of
Salmonella
strains belonging to commonly encountered serovars and isolated from a given geographical area, assuming that the system has been validated beforehand with a significant number of strains originating from that particular area.
DNA-Level Diversity and Relatedness of
Helicobacter pylori
Strains in Shantytown Families in Peru and Transmission in a Developing-Country Setting
Authors: Herrera Phabiola M. , Mendez Melissa , Velapatiõ Billie , Santivaẽz Livia , Balqui Jacqueline , Finger S. Alison , Sherman Jonathan , Zimic Mirko , Cabrera Lilia , Watanabe Jose , Rodríguez Carlos , Gilman Robert H. , Berg Douglas E. 
Published: October 2008

ABSTRACT

The efficiency of transmission of a pathogen within families compared with that between unrelated persons can affect both the strategies needed to control or eradicate infection and how the pathogen evolves. In industrialized countries, most cases of transmission of the gastric pathogen
Helicobacter pylori
seems to be from mother to child. An alternative model, potentially applicable among the very poor in developing countries, where infection is more common and the sanitary infrastructure is often deficient, invokes frequent transmission among unrelated persons, often via environmental sources. In the present study, we compared the genotypes of
H. pylori
from members of shantytown households in Peru to better understand the transmission of
H. pylori
in developing-country settings.
H. pylori
cultures and/or DNAs were obtained with informed consent by the string test (a minimally invasive alternative to endoscopy) from at least one child and one parent from each of 62 families. The random amplified polymorphic DNA fingerprints of 57 of 81 (70%) child-mother strain pairs did not match, nor did the diagnostic gene sequences (>1% DNA sequence difference), independent of the child's age (range, 1 to 39 years). Most strains from siblings or other paired family members were also unrelated. These results suggest that
H. pylori
infections are often community acquired in the society studied. Transmission between unrelated persons should facilitate the formation of novel recombinant genotypes by interstrain DNA transfer and selection for genotypes that are well suited for individual hosts. It also implies that the effective prevention of
H. pylori
infection and associated gastroduodenal disease will require anti-
H. pylori
measures to be applied communitywide.
Neuroadapted Yellow Fever Virus Strain 17D: a Charged Locus in Domain III of the E Protein Governs Heparin Binding Activity and Neuroinvasiveness in the SCID Mouse Model
Authors: Nickells Janice , Cannella Maria , Droll Deborah A. , Liang Yan , Wold William S. M. , Chambers Thomas J. 
Published: October 2008

ABSTRACT
A molecular clone of yellow fever virus (YFV) strain 17D was used to identify critical determinants of mouse neuroinvasiveness previously localized to domain III of the neuroadapted SPYF-MN virus envelope protein. Three candidate virulence substitutions (305F→V, 326K→E, and 380R→T) were individually evaluated for their roles in this phenotype in a SCID mouse model. The virus containing a glutamic acid residue at position 326 of the envelope protein (326E) caused rapidly lethal encephalitis, with a mortality rate and average survival time resembling those of the parental SPYF-MN virus. Determinants at positions 380 (380T) and 305 (305V) did not independently affect neuroinvasiveness. Testing a panel of viruses with various amino acid substitutions at position 326 revealed that attenuation of neuroinvasiveness required a positively charged residue (lysine or arginine) at this position. Molecular-modeling studies suggest that residues 326 and 380 contribute to charge clusters on the lateral surface of domain III that constitute putative heparin binding sites, as confirmed by studies of heparin inhibition of plaque formation. The neuroinvasiveness of YFVs in the SCID model correlated inversely with sensitivity to heparin. These findings establish that residue 326 in domain III of the E protein is a critical determinant of YFV neuroinvasiveness in the SCID mouse model. Together with modeling of domain III from virulent YFV strains, the data suggest that heparin binding activity involving lysine at position 326 may be a modulator of YFV virulence phenotypes.
Lack of Heparan Sulfate Expression in B-Cell Lines: Implications for Kaposi's Sarcoma-Associated Herpesvirus and Murine Gammaherpesvirus 68 Infections
Authors: Jarousse Nadine , Chandran Bala , Coscoy Laurent 
Published: October 2008

ABSTRACT
Kaposi's sarcoma-associated herpesvirus (KSHV) and its murine homolog, murine gammaherpesvirus 68 (MHV68), are lymphotropic viruses that establish latent infection in their host. Surprisingly, while B cells are the main viral reservoir in vivo, B-cell lines are poorly permissive to infection by either MHV68 or KSHV. Here, we report that most B-cell lines express very little to no cell surface heparan sulfate (HS), a glycosaminoglycan that is essential for infection by these viruses. We found that Ext1, a key enzyme in the biosynthesis of HS, was expressed at a low level in these cells. Transfection of B-cell lines with Ext1 restored high HS expression at the cell surface. Overexpression of Ext1 in murine A20 and M12 B-cell lines increased MHV68 surface binding and enhanced the efficiency of infection. Finally, although it was not sufficient to allow efficient infection, the expression of HS on BJAB cells promoted KSHV binding at the cell surface. Thus, our results indicate that MHV68 and KSHV cycles are blocked in B-cell lines at the binding step due to a lack of surface HS.
Role of Homodimerization of Human Cytomegalovirus DNA Polymerase Accessory Protein UL44 in Origin-Dependent DNA Replication in Cells
Authors: Sinigalia Elisa , Alvisi Gualtiero , Mercorelli Beatrice , Coen Donald M. , Pari Gregory S. , Jans David A. , Ripalti Alessandro , Palù Giorgio , Loregian Arianna 
Published: October 2008

ABSTRACT

The presumed processivity subunit of human cytomegalovirus (HCMV) DNA polymerase, UL44, forms homodimers. The dimerization of UL44 is important for binding to DNA in vitro; however, whether it is also important for DNA replication in a cellular context is unknown. Here we show that UL44 point mutants that are impaired for dimerization, but not for nuclear localization or interaction with the C terminus of the polymerase catalytic subunit, are not capable of supporting HCMV
ori
Lyt-dependent DNA replication in cells. These data suggest that the disruption of UL44 homodimers could represent a novel anti-HCMV strategy.
Passive Immunization Reduces Murine Cytomegalovirus-Induced Brain Pathology in Newborn Mice
Authors: Cekinović Đurđica , Golemac Mijo , Pugel Ester Pernjak , Tomac Jelena , Čičin-Šain Luka , Slavuljica Irena , Bradford Russell , Misch Sonja , Winkler Thomas H. , Mach Michael , Britt William J. , Jonjić Stipan 
Published: October 2008

ABSTRACTHuman cytomegalovirus (HCMV) is the most frequent cause of congenital viral infections in humans and frequently leads to long-term central nervous system (CNS) abnormalities that include learning disabilities, microcephaly, and hearing loss. The pathogenesis of the CNS infection has not been fully elucidated and may arise as a result of direct damage of CMV-infected neurons or indirectly secondary to inflammatory response to infection. We used a recently established model of mouse CMV (MCMV) infection in newborn mice to analyze the contribution of humoral immunity to virus clearance from the brain. In brains of MCMV-infected newborn mice treated with immune serum, the titer of infectious virus was reduced below detection limit, whereas in the brains of mice receiving control (nonimmune) serum significant amounts of virus were recovered. Moreover, histopathological and immunohistological analyses revealed significantly less CNS inflammation in mice treated with immune serum. Treatment with MCMV-specific monoclonal antibodies also resulted in the reduction of virus titer in the brain. Recipients of control serum or irrelevant antibodies had more viral foci, marked mononuclear cell infiltrates, and prominent glial nodules in their brains than mice treated with immune serum or MCMV-specific antibodies. In conclusion, our data indicate that virus-specific antibodies have a protective role in the development of CNS pathology in MCMV-infected newborn mice, suggesting that antiviral antibodies may be an important component of protective immunological responses during CMV infection of the developing CNS.
Topology and Membrane Anchoring of the Coronavirus Replication Complex: Not All Hydrophobic Domains of nsp3 and nsp6 Are Membrane Spanning
Authors: Oostra Monique , Hagemeijer Marne C. , van Gent Michiel , Bekker Cornelis P. J. , te Lintelo Eddie G. , Rottier Peter J. M. , de Haan Cornelis A. M. 
Published: October 2008

ABSTRACT
Coronaviruses express two very large replicase polyproteins, the 16 autoproteolytic cleavage products of which collectively form the membrane-anchored replication complexes. How these structures are assembled is still largely unknown, but it is likely that the membrane-spanning members of these nonstructural proteins (nsps) are responsible for the induction of the double-membrane vesicles and for anchoring the replication complexes to these membranes. For 3 of the 16 coronavirus nsps—nsp3, nsp4, and nsp6—multiple transmembrane domains are predicted. Previously we showed that, consistent with predictions, nsp4 occurs in membranes with both of its termini exposed in the cytoplasm (M. Oostra et al., J. Virol. 81:12323-12336, 2007). Strikingly, however, for both nsp3 and nsp6, predictions based on a multiple alignment of 27 coronavirus genome sequences indicate an uneven number of transmembrane domains. As a consequence, the proteinase domains present in nsp3 and nsp5 would be separated from their target sequences by the lipid bilayer. To look into this incongruity, we studied the membrane disposition of nsp3 and nsp6 of the severe acute respiratory syndrome coronavirus and murine hepatitis virus by analyzing tagged forms of the proteins expressed in cultured cells. Contrary to the predictions, in both viruses, both proteins had their amino terminus, as well as their carboxy terminus, exposed in the cytoplasm. We established that two of the three hydrophobic domains in nsp3 and six of the seven in nsp6 are membrane spanning. Subsequently, we verified that in nsp4, all four hydrophobic domains span the lipid bilayer. The occurrence of conserved non-membrane-spanning hydrophobic domains in nsp3 and nsp6 suggests an important function for these domains in coronavirus replication.
Memory CD4+T-Cell-Mediated Protection from Lethal Coronavirus Encephalomyelitis
Authors: Savarin Carine , Bergmann Cornelia C. , Hinton David R. , Ransohoff Richard M. , Stohlman Stephen A. 
Published: October 2008

ABSTRACTThe antiviral role of CD4+T cells in virus-induced pathologies of the central nervous system (CNS) has not been explored extensively. Control of neurotropic mouse hepatitis virus (JHMV) requires the collaboration of CD4+and CD8+T cells, with CD8+T cells providing direct perforin and gamma interferon (IFN-γ)-mediated antiviral activity. To distinguish bystander from direct antiviral contributions of CD4+T cells in virus clearance and pathology, memory CD4+T cells purified from wild type (wt), perforin-deficient (PKO), and IFN-γ-deficient (GKO) immune donors were transferred to immunodeficient SCID mice prior to CNS challenge. All three donor CD4+T-cell populations controlled CNS virus replication at 8 days postinfection, indicating IFN-γ- and perforin-independent antiviral function. Recipients of GKO CD4+T cells succumbed more rapidly to fatal disease than untreated control infected mice. In contrast, wt and PKO donor CD4+T cells cleared infectious virus to undetectable levels and protected from fatal disease. Recipients of all CD4+T-cell populations exhibited demyelination. However, it was more severe in wt CD4+T-cell recipients. These data support a role of CD4+T cells in virus clearance and demyelination. Despite substantial IFN-γ-independent antiviral activity, IFN-γ was crucial in providing protection from death. IFN-γ reduced neutrophil accumulation and directed macrophages to white matter but did not ameliorate myelin loss.
The Zinc RING Finger of Bovine Herpesvirus 1-Encoded bICP0 Protein Is Crucial for Viral Replication and Virulence
Authors: Saira Kazima , Chowdhury Shafiqul , Gaudreault Natasha , da Silva Leticia , Henderson Gail , Doster Alan , Jones Clinton 
Published: October 2008

ABSTRACT

Bovine herpesvirus 1 (BHV-1) infected cell protein 0 (bICP0) stimulates productive infection, in part by activating viral gene expression. The C
3
HC
4
zinc RING finger of bICP0 is crucial for activating viral transcription and productive infection. In this study, we used a bacterial artificial chromosome containing a wild-type (wt) virulent BHV-1 strain to generate a single amino acid mutation in the C
3
HC
4
zinc RING finger of bICP0. This virus (the 51g mutant) contains a cysteine-to-glycine mutation (51st amino acid) in the C
3
HC
4
zinc RING finger of bICP0. A plasmid expressing the 51g mutant protein did not transactivate viral promoter activity as efficiently as wt bICP0. The 51g mutant virus expressed higher levels of the bICP0 protein than did the 51g rescued virus (51gR) but yielded reduced virus titers following infection of permissive bovine cells. The 51g mutant virus, but not the 51gR virus, grew poorly in bovine cells pretreated with imiquimod to stimulate interferon production. During acute infection of calves, levels of infectious virus were 2 to 3 logs lower in ocular or nasal swabs with 51g than with 51gR. Calves latently infected with the 51g mutant did not reactivate from latency because virus shedding did not occur in ocular or nasal cavities. As expected, calves latently infected with 51gR reactivated from latency following dexamethasone treatment. These studies demonstrate that mutation of a single well-conserved cysteine residue in the C
3
HC
4
zinc RING finger of bICP0 has dramatic effects on the growth properties of BHV-1.