bluuebunny/crossref_metadata_2025_split huggingface dataset:
Identification of Haemophilus influenzae Clones Associated with Invasive Disease a Decade after Introduction of H. influenzae Serotype b Vaccination in Italy
Authors: Giufrè Maria , Cardines Rita , Accogli Marisa , Pardini Manuela , Cerquetti Marina 
Published: June 2013

ABSTRACT

The introduction of
Haemophilus influenzae
serotype b (Hib) conjugate vaccines has changed the epidemiology of invasive
H. influenzae
disease, with a shift in the predominant serotype from Hib to nonencapsulated
H. influenzae
(ncHi). The objective of this study was to identify the genotypes/clones associated with invasive
H. influenzae
disease in Italy. Eighty-seven
H. influenzae
strains isolated in the years 2009 to 2011 within the National Surveillance of Invasive Bacterial Disease program were analyzed. Strains were characterized by serotyping, antimicrobial susceptibility testing, and multilocus sequence typing (MLST). Genetic polymorphisms in the
bla
TEM
gene promoter region as well as the occurrence of both adhesin genes (
hmwA
and
hia
) and the IgA1 protease-encoding gene (
igaB
) were also investigated. Of 87 strains, 67 were ncHi and 20 were encapsulated. Eleven strains were β-lactamase positive, harboring the
bla
TEM
gene. Most
bla
TEM
genes (10/11) were associated with a Pdel promoter region exhibiting a 135-bp deletion; the remaining strain possessed the Pa/Pb overlapping promoter. MLST analysis showed that encapsulated isolates were clonal, with each serotype sharing a few related sequence types (STs). Forty-six different STs were identified among the 67 ncHi strains. Despite this heterogeneity, a group of closely related STs (ST103, ST139, and ST145) encompassed almost 25% of all ncHi strains and 45.5% of the β-lactamase producers carrying the Pdel promoter. These major ST clones were found to be associated with the
hmwA
gene but not with the
igaB
gene. To conclude, although the heterogeneity of the ncHi population was confirmed, diffusion of major successful ST clones was documented.
Development and Comparative Evaluation of a Plate Enzyme-Linked Immunosorbent Assay Based on Recombinant Outer Membrane Antigens Omp28 and Omp31 for Diagnosis of Human Brucellosis
Authors: Tiwari Sapana , Kumar Ashu , Thavaselvam Duraipandian , Mangalgi Smita , Rathod Vedika , Prakash Archana , Barua Anita , Arora Sonia , Sathyaseelan Kannusamy 
Published: June 2013

ABSTRACT

Brucellosis is an important zoonotic infectious disease of humans and livestock with worldwide distribution and is caused by bacteria of the genus
Brucella
. The diagnosis of brucellosis always requires laboratory confirmation by either isolation of pathogens or detection of specific antibodies. The conventional serological tests available for the diagnosis of brucellosis are less specific and show cross-reactivity with other closely related organisms. These tests also necessitate the handling of
Brucella
species for antigen preparation. Therefore, there is a need to develop reliable, rapid, and user-friendly systems for disease diagnosis and alternatives to vaccine approaches. Keeping in mind the importance of brucellosis as an emerging infection and the prevalence in India, we carried out the present study to compare the recombinant antigens with the native antigens (cell envelope and sonicated antigen) of
Brucella
for diagnosis of human brucellosis by an indirect plate enzyme-linked immunosorbent assay (ELISA). Recombinant outer membrane protein 28 (rOmp28) and rOmp31 antigens were cloned, expressed, and purified in the bacterial expression system, and the purified proteins were used as antigens. Indirect plate ELISAs were then performed and standardized for comparison of the reactivities of recombinant and native antigens against the 433 clinical samples submitted for brucellosis testing, 15 culture-positive samples, and 20 healthy donor samples. The samples were separated into four groups based on their positivity to rose bengal plate agglutination tests (RBPTs), standard tube agglutination tests (STATs), and 2-mercaptoethanol (2ME) tests. The sensitivities and specificities of all the antigens were calculated, and the rOmp28 antigen was found to be more suitable for the clinical diagnosis of brucellosis than the rOmp31 antigen and native antigens. The rOmp28-based ELISA showed a very high degree of agreement with the conventional agglutination tests and promising results for further use in clinical screening and serodiagnosis of human brucellosis.
Inhibitory Humoral Responses to the Plasmodium falciparum Vaccine Candidate EBA-175 Are Independent of the Erythrocyte Invasion Pathway
Authors: Badiane Aida S. , Bei Amy K. , Ahouidi Ambroise D. , Patel Saurabh D. , Salinas Nichole , Ndiaye Daouda , Sarr Ousmane , Ndir Omar , Tolia Niraj H. , Mboup Souleymane , Duraisingh Manoj T. 
Published: June 2013

ABSTRACT

Plasmodium falciparum
utilizes multiple ligand-receptor interactions for invasion. The invasion ligand EBA-175 is being developed as a major blood-stage vaccine candidate. EBA-175 mediates parasite invasion of host erythrocytes in a sialic acid-dependent manner through its binding to the erythrocyte receptor glycophorin A. In this study, we addressed the ability of naturally acquired human antibodies against the EBA-175 RII erythrocyte-binding domain to inhibit parasite invasion of
ex vivo
isolates, in relationship to the sialic acid dependence of these parasites. We have determined the presence of antibodies to the EBA-175 RII domain by enzyme-linked immunosorbent assay (ELISA) in individuals from areas of Senegal where malaria is endemic with high and low transmission. Using affinity-purified human antibodies to the EBA-175 RII domain from pooled patient plasma, we have measured the invasion pathway as well as the invasion inhibition of clinical isolates from Senegalese patients in
ex vivo
assays. Our results suggest that naturally acquired anti-EBA-175 RII antibodies significantly inhibit invasion of Senegalese parasites and that these responses can be significantly enhanced through limiting other ligand-receptor interactions. However, the extent of this functional inhibition by EBA-175 antibodies is not associated with the sialic acid dependence of the parasite strain, suggesting that erythrocyte invasion pathway usage by parasite strains is not driven by antibodies targeting the EBA-175/glycophorin A interaction. This work has implications for vaccine design based on the RII domain of EBA-175 in the context of alternative invasion pathways.
The Receptor Binding Domain of Botulinum Neurotoxin Serotype A (BoNT/A) Inhibits BoNT/A and BoNT/E Intoxications
In Vivo
Authors: Ben David Alon , Diamant Eran , Barnea Ada , Rosen Osnat , Torgeman Amram , Zichel Ran 
Published: June 2013

ABSTRACT

The receptor binding domain of botulinum neurotoxin (BoNT), also designated the C terminus of the heavy chain (H
C
), is a promising vaccine candidate against botulism. In this study, a highly efficient expression system for the protein was developed in
Escherichia coli
, which provided yields that were 1 order of magnitude higher than those reported to date (350 mg H
C
per liter). The product was highly immunogenic, protecting mice from a challenge with 10
5
50% lethal dose (LD
50
) after a single vaccination and generating a neutralizing titer of 49.98 IU/ml after three immunizations. In addition, a single boost with H
C
increased neutralizing titers by up to 1 order of magnitude in rabbits hyperimmunized against toxoid. Moreover, we demonstrate here for the first time
in vivo
inhibition of BoNT/A intoxication by H
C
/A, presumably due to a blockade of the neurotoxin protein receptor SV2. Administration of H
C
/A delayed the time to death from 10.4 to 27.3 h in mice exposed to a lethal dose of BoNT/A (
P
= 0.0005). Since BoNT/A and BoNT/E partially share SV2 isoforms as their protein receptors, the ability of H
C
/A to cross-inhibit BoNT/E intoxication was evaluated. The administration of H
C
/A together with BoNT/E led to 50% survival and significantly delayed the time to death for the nonsurviving mice (
P
= 0.003). Furthermore, a combination of H
C
/A and a subprotective dose of antitoxin E fully protected mice against 850 mouse LD
50
of BoNT/E, suggesting complementary mechanisms of protection consisting of toxin neutralization by antibodies and receptor blocking by H
C
/A.
Improved Detection of Bacterial Pathogens in Patients Presenting with Gastroenteritis by Use of the EntericBio Real-Time Gastro Panel I Assay
Authors: Koziel Monika , Kiely Rachel , Blake Liam , O'Callaghan Isabelle , Corcoran Gerard D. , Lucey Brigid , Sleator Roy D. 
Published: June 2013

ABSTRACT

In this study, we evaluated the use of EntericBio real-time Gastro Panel I (Serosep, Limerick, Ireland) for routine use in a clinical microbiology laboratory for simultaneous detection of
Campylobacter jejuni
,
coli
, and
lari
, Shiga toxin-producing
Escherichia coli
(STEC),
Salmonella
spp., and
Shigella
spp. in feces. This system differs from its predecessor (the EntericBio Panel II system, Serosep) in that it allows real-time detection of pathogens directly from feces, without pre-enrichment. It also specifically detects
Campylobacter jejuni
,
coli
, and
lari
rather than all
Campylobacter
species, as is the case with the previous system. A total of 528 samples from patients presenting with acute gastroenteritis were screened prospectively with this assay, and results were compared with those of the current method, which combines screening the samples with a molecular assay (the EntericBio Panel II assay) and retrospective culture of the specimens in which the target was detected. Discrepancy analysis was conducted using culture and molecular methods. The real-time assay produced 84 positive results, specifically,
Campylobacter
spp. (
n
= 44); Stx1 and/or Stx2 (
n
= 35);
Shigella
spp. (
n
= 3); and
Salmonella
spp. (
n
= 6). Of these, 4 samples represented coinfections with
Campylobacter
spp. and STEC. The real-time assay showed an increased detection rate for pathogens, apart from
Salmonella
spp. Four
Campylobacter
-positive and 6 Stx-positive results remained unconfirmed by any other method used. The isolation rates for PCR-positive samples were as follows:
Campylobacter
spp., 80%; STEC, 45.7%;
Salmonella
spp., 100%; and
Shigella
spp., 66.7%. The sensitivity, specificity, positive predictive value, negative predictive value, and efficiency were 100%, 97.8%, 88.1%, 100%, and 98.1%, respectively.
How Positive-Strand RNA Viruses Benefit from Autophagosome Maturation
Authors: Richards Alexsia L. , Jackson William T. 
Published: June 2013

ABSTRACT
The autophagic degradation pathway is a powerful tool in the host cell arsenal against cytosolic pathogens. Contents trapped inside cytosolic vesicles, termed autophagosomes, are delivered to the lysosome for degradation. In spite of the degradative nature of the pathway, some pathogens are able to subvert autophagy for their benefit. In many cases, these pathogens have developed strategies to induce the autophagic signaling pathway while inhibiting the associated degradation activity. One surprising finding from recent literature is that some viruses do not impede degradation but instead promote the generation of degradative autolysosomes, which are the endpoint compartments of autophagy. Dengue virus, poliovirus, and hepatitis C virus, all positive-strand RNA viruses, utilize the maturation of autophagosomes into acidic and ultimately degradative compartments to promote their replication. While the benefits that each virus reaps from autophagosome maturation are unique, the parallels between the viruses indicate a complex relationship between cytosolic viruses and host cell degradation vesicles.
Template RNA Length Determines the Size of Replication Complex Spherules for Semliki Forest Virus
Authors: Kallio Katri , Hellström Kirsi , Balistreri Giuseppe , Spuul Pirjo , Jokitalo Eija , Ahola Tero 
Published: June 2013

ABSTRACT

The replication complexes of positive-strand RNA viruses are always associated with cellular membranes. The morphology of the replication-associated membranes is altered in different ways in different viral systems, but many viruses induce small membrane invaginations known as spherules as their replication sites. We show here that for Semliki Forest virus (SFV), an alphavirus, the size of the spherules is tightly connected with the length of the replicating RNA template. Cells with different model templates, expressed in
trans
and copied by the viral replicase, were analyzed with correlative light and electron microscopy. It was demonstrated that the viral-genome-sized template of 11.5 kb induced spherules that were ∼58 nm in diameter, whereas a template of 6 kb yielded ∼39-nm spherules. Different sizes of viral templates were replicated efficiently in
trans
, as assessed by radioactive labeling and Northern blotting. The replication of two different templates, in
cis
and
trans
, yielded two size classes of spherules in the same cell. These results indicate that RNA plays a crucial determining role in spherule assembly for SFV, in direct contrast with results from other positive-strand RNA viruses, in which either the presence of viral RNA or the RNA size do not contribute to spherule formation.
Characterization of the 2012 Highly Pathogenic Avian Influenza H7N3 Virus Isolated from Poultry in an Outbreak in Mexico: Pathobiology and Vaccine Protection
Authors: Kapczynski Darrell R. , Pantin-Jackwood Mary , Guzman Sofia G. , Ricardez Yadira , Spackman Erica , Bertran Kateri , Suarez David L. , Swayne David E. 
Published: June 2013

ABSTRACT
In June of 2012, an H7N3 highly pathogenic avian influenza (HPAI) virus was identified as the cause of a severe disease outbreak in commercial laying chicken farms in Mexico. The purpose of this study was to characterize the Mexican 2012 H7N3 HPAI virus (A/chicken/Jalisco/CPA1/2012) and determine the protection against the virus conferred by different H7 inactivated vaccines in chickens. Both adult and young chickens intranasally inoculated with the virus became infected and died at between 2 and 4 days postinoculation (p.i.). High virus titers and viral replication in many tissues were demonstrated at 2 days p.i. in infected birds. The virus from Jalisco, Mexico, had high sequence similarity of greater than 97% to the sequences of wild bird viruses from North America in all eight gene segments. The hemagglutinin gene of the virus contained a 24-nucleotide insert at the hemagglutinin cleavage site which had 100% sequence identity to chicken 28S rRNA, suggesting that the insert was the result of nonhomologous recombination with the host genome. For vaccine protection studies, both U.S. H7 low-pathogenic avian influenza (LPAI) viruses and a 2006 Mexican H7 LPAI virus were tested as antigens in experimental oil emulsion vaccines and injected into chickens 3 weeks prior to challenge. All H7 vaccines tested provided ≥90% protection against clinical disease after challenge and decreased the number of birds shedding virus and the titers of virus shed. This study demonstrates the pathological consequences of the infection of chickens with the 2012 Mexican lineage H7N3 HPAI virus and provides support for effective programs of vaccination against this virus in poultry.
Murine Cytomegalovirus Protein pM79 Is a Key Regulator for Viral Late Transcription
Authors: Chapa Travis J. , Johnson L. Steven , Affolter Christopher , Valentine Mark C. , Fehr Anthony R. , Yokoyama Wayne M. , Yu Dong 
Published: June 2013

ABSTRACT

Herpesvirus genes are temporally expressed during permissive infections, but how their expression is regulated at late times is poorly understood. Previous studies indicate that the human cytomegalovirus (CMV) gene, UL79, is required for late gene expression. However, the mechanism remains to be fully elucidated, and UL79 homologues in other CMVs have not been studied. Here, we characterized the role of the conserved murine CMV (MCMV) gene M79. We showed that M79 encoded a protein (pM79) which was expressed with early-late kinetics and localized to nuclear viral replication compartments. M79 transcription was significantly decreased in the absence of viral DNA synthesis but markedly stimulated by pM79. To investigate its role, we created the recombinant virus SM
in
79, in which pM79 expression was disrupted. While marker-rescued virus grew efficiently in fibroblasts, SM
in
79 failed to produce infectious progeny but was rescued by pM79 expression
in trans
. During SM
in
79 infection, representative viral immediate-early and early gene products as well as viral DNA accumulated sufficiently. Formation of viral replication compartments also appeared normal. Pulsed-field gel electrophoresis analysis indicated that the overall structure of replicating viral DNA was indistinguishable between wild-type and SM
in
79 infection. Viral tiled array and quantitative PCR analysis revealed that many late transcripts sensitive to a viral DNA synthesis inhibitor (phosphonoacetic acid) were markedly reduced by pM79 mutation. This study indicates that cytomegaloviruses use a conserved mechanism to promote transcription at late stages of infection and that pM79 is a critical regulator for at least a subset of viral DNA synthesis-dependent transcripts.
Infection with Feline Immunodeficiency Virus Directly Activates CD4
+
CD25
+
T Regulatory Cells
Authors: Miller Michelle M. , Fogle Jonathan E. , Tompkins Mary B. 
Published: June 2013

ABSTRACT

Lentivirus infection activates CD4
+
CD25
+
T regulatory (Treg) cells. Activation of Treg cells may be due to direct virus infection or chronic antigenic stimulation. Herein we demonstrate that
in vitro
feline immunodeficiency virus (FIV) infection, but not UV-inactivated virus, activates Treg cells as measured by immunosuppressive function and upregulation of GARP, FoxP3, and membrane-bound transforming growth factor β (TGF-β). These data demonstrate for the first time that AIDS lentiviruses infect and activate Treg cells, potentially contributing to immune dysfunction.
High Levels of CD2 Expression Identify HIV-1 Latently Infected Resting Memory CD4+T Cells in Virally Suppressed Subjects
Authors: Iglesias-Ussel Maria , Vandergeeten Claire , Marchionni Luigi , Chomont Nicolas , Romerio Fabio 
Published: June 2013

ABSTRACTResting memory CD4+T cells are the largest reservoir of persistent infection in HIV-1-positive subjects. They harbor dormant, stably integrated virus despite suppressive antiretroviral therapy, posing an obstacle to a cure. Surface markers that identify latently infected cells remain unknown. Microarray analyses comparing resting latently infected and uninfected CD4+T cells generatedin vitroshowed profound differences in the expression of gene programs related to transcriptional and posttranscriptional regulation, cell proliferation, survival, cycle progression, and basic metabolism, suggesting that multiple biochemical and metabolic blocks contribute to preventing viral production in latently infected cells. We identified 33 transcripts encoding cell surface markers that are differentially expressed between latently infected and uninfected cells. Quantitative reverse transcriptase PCR (RT-QPCR) and flow cytometry analyses confirmed that the surface marker CD2 was expressed at higher levels on latently infected cells. To validate this resultin vivo, we sorted resting memory CD4+T cells expressing high and low surface levels of CD2 from six HIV-1-infected subjects successfully treated with antiretroviral drugs for at least 3 years. Resting memory CD4+CD2highT cells from all subjects harbored higher HIV-1 DNA copy numbers than all other CD4+T cell subsets. Moreover, afterex vivoviral reactivation, robust viral RNA production was detected only from resting memory CD4+CD2highT cells but not from other cell subsets. Altogether, these results show that a high CD2 expression level is a hallmark of latently infected resting memory CD4+T cellsin vivo.
Hospital workers’ perceptions of waste: a qualitative study involving photo-elicitation
Authors: Goff Sarah L , Kleppel Reva , Lindenauer Peter K , Rothberg Michael B 
Published: June 2013

ObjectivesTo elicit sources of waste as viewed by hospital workers.DesignQualitative study using photo-elicitation, an ethnographic technique for prompting in-depth discussion.SettingU.S. academic tertiary care hospital.ParticipantsPhysicians, nurses, pharmacists, administrative support personnel, administrators and respiratory therapists.MethodsA purposive sample of personnel at an academic tertiary care hospital was invited to take up to 10 photos of waste. Participants discussed their selections using photos as prompts during in-depth interviews. Transcripts were analysed in an iterative process using grounded theory; open and axial coding was performed, followed by selective and thematic coding to develop major themes and subthemes.ResultsTwenty-one participants (nine women, average number of years in field=19.3) took 159 photos. Major themes included types of waste and recommendations to reduce waste. Types of waste comprised four major categories: Time, Materials, Energy and Talent. Participants emphasised time wastage (50% of photos) over other types of waste such as excess utilisation (2.5%). Energy and Talent were novel categories of waste. Recommendations to reduce waste included interventions at the micro-level (eg, individual/ward), meso-level (eg, institution) and macro-level (eg, payor/public policy).ConclusionsThe waste hospital workers identified differed from previously described waste both in the types of waste described and the emphasis placed on wasted time. The findings of this study represent a possible need for education of hospital workers about known types of waste, an opportunity to assess the impact of novel types of waste described and an opportunity to intervene to reduce the waste identified.
Household-based socioeconomic position and diabetes-related mortality among married and cohabiting persons: findings from a census-based cohort study (Flanders, 2001–2010)
Authors: Vandenheede Hadewijch , Vanroelen Christophe , Gadeyne Sylvie , De Grande Hannelore , Deboosere Patrick 
Published: June 2013

BackgroundDiabetes prevalence is high worldwide, affecting entire populations. Yet some population groups are more susceptible than others. In contemporary western societies, socioeconomically disadvantaged groups are disproportionally affected. The pattern is less clear for diabetes mortality. Researchers argue increasingly in favour of looking beyond individual socioeconomic position (SEP). In light of the above, this paper looks at the relationship between individual-based and household-based SEP measures and diabetes mortality.MethodsData consisted of the Belgian 2001 census for the Flanders region linked to register data on cause-specific mortality during the period 2001–2010. The study population included all 35-year-old to 74-year-old official inhabitants of Flanders married or cohabiting at the 2001 census. Age-standardised death rates (direct standardisation) and mortality rate ratios (MRRs; Poisson regression) were computed for the different SEP groups.ResultsInverse gradients were observed by own education, partner's education and housing status (combination of housing tenure and quality). For example, among 55-year-olds to 74-year-olds, MRRs according to partner's education were 3.0 (95% CI 2.4 to 3.8) for women with a lower-educated partner and 1.6 (95% CI 1.2 to 2.0) for women with a higher secondary-educated partner, relative to women with a higher-educated partner. As for housing status, diabetes-related mortality was particularly high among tenants and low-quality owners. The association between each of the SEP measures and diabetes-related mortality remained after adjusting for the other measures.ConclusionsThere were large differences in diabetes-related mortality according to both individual-based and household-based SEP measures, indicating the importance of the individual and household levels for understanding socioeconomic inequalities in diabetes mortality.