bluuebunny/crossref_metadata_2025_split huggingface dataset:
Acinetobacter soli as a Cause of Bloodstream Infection in a Neonatal Intensive Care Unit
Authors: Pellegrino Flávia Lúcia Piffano Costa , Vieira Verônica V. , Baio Paulo Victor Pereira , dos Santos Rosana Maria R. , dos Santos Ana Lucia Alves , Santos Nadir Gomes de Barros , Meohas Martha Maria Gaudie Ley , Santos Rodrigo Teixeira , de Souza Talita Coelho , da Silva Dias Rubens Clayton , Santoro-Lopes Guilherme , Riley Lee W. , Moreira Beatriz Meurer 
Published: April 2011

ABSTRACT

Acinetobacter soli
is a new bacterial species described from forest soil. Five cases of bloodstream infection caused by
A. soli
clonal isolates are reported here for the first time. The patients were neonates admitted to an intensive care unit. This is a new neonatal pathogen with the potential to cause outbreaks.
Cutaneous Diphtheria in the Urban Poor Population of Vancouver, British Columbia, Canada: a 10-Year Review
Authors: Lowe C. F. , Bernard K. A. , Romney M. G. 
Published: April 2011

ABSTRACT

Between 1998 and 2007, records from 33 patients with cutaneous diphtheria from Vancouver's inner city were reviewed. Cases were associated with injection drug use and poverty. Coinfections with
Staphylococcus aureus
,
Streptococcus pyogenes
, and
Arcanobacterium haemolyticum
occurred.
Corynebacterium diphtheriae
is endemic in Vancouver's urban core, with strains of multilocus sequence type (MLST) 76 predominating.
Comparison of Automated Processing of Flocked Swabs with Manual Processing of Fiber Swabs for Detection of Nasal Carriage of
Staphylococcus aureus
Authors: Jones Gillian , Matthews Roger , Cunningham Richard , Jenks Peter 
Published: April 2011

ABSTRACT

The sensitivity of automated culture of
Staphylococcus
aureus
from flocked swabs versus that of manual culture of fiber swabs was prospectively compared using nasal swabs from 867 patients. Automated culture from flocked swabs significantly increased the detection rate, by 13.1% for direct culture and 10.2% for enrichment culture.
Comparison of the Flotac-400 Dual Technique and the Formalin-Ether Concentration Technique for Diagnosis of Human Intestinal Protozoon Infection
Authors: Becker Sören L. , Lohourignon Laurent K. , Speich Benjamin , Rinaldi Laura , Knopp Stefanie , N'Goran Eliézer K. , Cringoli Giuseppe , Utzinger Jürg 
Published: April 2011

ABSTRACT

There is a need for accurate diagnosis of intestinal parasite infections in humans, but currently available copromicroscopic techniques have shortcomings, such as low sensitivity. We compared the diagnostic accuracy of a further modified version of the recently developed Flotac technique with that of the widely used formalin-ether concentration technique (FECT) for the detection of intestinal protozoa in human stool samples. Formaldehyde-preserved stool samples from 108 individuals in Côte d'Ivoire were subjected to the Flotac-400 dual technique, using two different flotation solutions (FS), and to the FECT. Stool samples were examined according to computer-generated random lists by an experienced laboratory technician blinded for the results of each method. Both methods detected the same eight intestinal protozoon species. While the Flotac-400 dual technique (results from both FS combined) found higher prevalences of
Entamoeba coli
(77.8% versus 71.3%,
P
< 0.001),
Blastocystis hominis
(20.4% versus 13.0%,
P
= 0.458), and
Giardia intestinalis
(8.3% versus 6.5%,
P
< 0.001), the FECT detected higher prevalences of
Entamoeba histolytica/Entamoeba dispar
(27.8% versus 20.4%,
P
= 0.019) and four species of nonpathogenic intestinal protozoa. The diagnostic agreement between the two methods differed considerably depending on the intestinal protozoon investigated (Cohen's kappa measures; range, 0.01 to 0.46). Our study confirmed that the Flotac-400 dual technique can be utilized for the diagnosis of intestinal protozoon infections in humans. Since Flotac is a sensitive technique for the detection of soil-transmitted helminths and
Schistosoma mansoni
, it might become a viable copromicroscopic technique for the concurrent diagnosis of helminths and intestinal protozoon infections.
Clinical and Molecular Observations of Two Fatal Cases of Rotavirus-Associated Enteritis in Children in Italy
Authors: Medici Maria Cristina , Abelli Laura Anna , Martinelli Monica , Corradi Domenico , Dodi Icilio , Tummolo Fabio , Albonetti Valeria , Martella Vito , Dettori Giuseppe , Chezzi Carlo 
Published: April 2011

ABSTRACT
Two fatal cases of infantile rotavirus enteritis occurred in northern Italy in 2005. Both children were severely dehydrated, and death was related to severe cerebral edema. Histological examination demonstrated extensive damage of the intestinal epithelium, villous atrophy or blunting, and macrophage infiltration. The two rotavirus strains were of the G1P[8] type and the long electropherotype. The 2005 G1P[8] rotaviruses differed in the NSP4, VP3, VP4, and VP7 genes from G1P[8] rotaviruses circulating in 2004, suggesting the onset of a new G1P[8] strain in the local population.
Shedding of Epstein-Barr Virus and Cytomegalovirus from the Genital Tract of Women in a Periurban Community in Andhra Pradesh, India
Authors: Silver Michelle I. , Paul Proma , Sowjanya Pavani , Ramakrishna Gayatri , Vedantham Haripriya , Kalpana Basany , Shah Keerti V. , Gravitt Patti E. 
Published: April 2011

ABSTRACT
We found a large number of false-positive readings by visual inspection with acetic acid (VIA) in a study of cervical cancer screening strategies (VIA, human papillomavirus HPV DNA testing, and Pap cytology) in a periurban community in Andhra Pradesh, India. We evaluated whether these false-positive readings might be occurring as a result of infections with Epstein-Barr virus (EBV) or cytomegalovirus (CMV), prevalent latent herpesviruses known to be shed from the female genital tract. While we found that there was no association between VIA results and the presence of EBV or CMV in the cervix, we did find a high prevalence of both viruses: 20% for EBV and 26% for CMV. In multivariate analyses, CMV prevalence was associated with younger age, lack of running water in the home, and visually apparent cervical inflammation. EBV prevalence was associated with older age and a diagnosis of cervical intraepithelial neoplasia grade 1 or greater. The biological and clinical implications of these viruses at the cervix remain to be determined. The strong association between the presence of EBV and cervical disease warrants future exploration to determine whether EBV plays a causal role in disease development or if it is merely a bystander in the process.
Solobacterium moorei Bacteremia: Identification, Antimicrobial Susceptibility, and Clinical Characteristics
Authors: Pedersen Rune Micha , Holt Hanne Marie , Justesen Ulrik Stenz 
Published: April 2011

ABSTRACT

We present five cases of
Solobacterium moorei
bacteremia. The isolates were identified with 16S rRNA gene sequencing and were susceptible to common antibiotics used for anaerobic infections. Bacteremia with
S. moorei
seems to be associated with debilitating conditions, but the prognosis of the infection appears to be good.
Sensitivity, Specificity, and Clinical Value of Human Papillomavirus (HPV) E6/E7 mRNA Assay as a Triage Test for Cervical Cytology and HPV DNA Test
Authors: Benevolo Maria , Vocaturo Amina , Caraceni Donatella , French Deborah , Rosini Sandra , Zappacosta Roberta , Terrenato Irene , Ciccocioppo Lucia , Frega Antonio , Rossi Paolo Giorgi 
Published: April 2011

ABSTRACT
There is evidence that testing for human papillomavirus (HPV) E6/E7 mRNA is more specific than testing for HPV DNA. A retrospective study was carried out to evaluate the performance of the PreTect HPV-Proofer E6/E7 mRNA assay (Norchip) as a triage test for cytology and HPV DNA testing. This study analyzed 1,201 women, 688 of whom had a colposcopy follow-up and 195 of whom had histology-confirmed high-grade intraepithelial neoplasia or worse (CIN2+). The proportion of positive results and the sensitivity and specificity for CIN2+ were determined for HPV mRNA in comparison to HPV DNA and cytology. All data were adjusted for follow-up completeness. Stratified by cytological grades, the HPV mRNA sensitivity was 83% (95% confidence interval [CI] = 63 to 94%) in ASC-US (atypical squamous cells of undetermined significance), 62% (95% CI = 47 to 75%) in L-SIL (low-grade squamous intraepithelial lesion), and 67% (95% CI = 57 to 76%) in H-SIL (high-grade squamous intraepithelial lesion). The corresponding figures were 99, 91, and 96%, respectively, for HPV DNA. The specificities were 82, 76, and 45%, respectively, for HPV mRNA and 29, 13, and 4%, respectively, for HPV DNA. Used as a triage test for ASC-US and L-SIL, mRNA reduced colposcopies by 79% (95% CI = 74 to 83%) and 69% (95% CI = 65 to 74%), respectively, while HPV DNA reduced colposcopies by 38% (95% CI = 32 to 44%) and by 15% (95% CI = 12 to 19%), respectively. As a HPV DNA positivity triage test, mRNA reduced colposcopies by 63% (95% CI = 60 to 66%), having 68% sensitivity (95% CI = 61 to 75%), whereas cytology at the ASC-US+ threshold reduced colposcopies by 23% (95% CI = 20 to 26%), showing 92% sensitivity (95% CI = 87 to 95%). In conclusion, PreTect HPV-Proofer mRNA can serve as a better triage test than HPV DNA to reduce colposcopy referral in both ASC-US and L-SIL. It is also more efficient than cytology for the triage of HPV DNA-positive women. Nevertheless, its low sensitivity demands a strict follow-up of HPV DNA positive-mRNA negative cases.
The Human T-Cell Leukemia Virus Type 1 Oncoprotein Tax Controls Forkhead Box O4 Activity through Degradation by the Proteasome
Authors: Oteiza Alexandra , Mechti Nadir 
Published: April 2011

ABSTRACT
Activation of the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) signaling pathway by the viral Tax oncoprotein plays a pivotal role in clonal expansion of human T-cell leukemia virus type 1 (HTLV-1)-infected cells. As the Forkhead box O (FoxO) tumor suppressors act as downstream effectors of PI3K/Akt, they represent good candidate targets whose dysregulation by Tax might be involved in HTLV-1-mediated activation and transformation of infected cells. In this report, we provide evidence showing that Tax induces a dose-dependent degradation of FoxO4 by the ubiquitin-proteasome pathway. Consistent with that, we demonstrate that Tax expression increases the interaction between FoxO4 and Mdm2 E3 ligase, leading to a strong FoxO4 polyubiquitination. These processes require the phosphorylation of FoxO4 by Akt, since a mutant of FoxO4 with mutations on its three Akt phosphorylation sites appears to be resistant to Tax-mediated degradation and ubiquitination. In addition, we show that Tax expression is associated with degradation and phosphorylation of endogenous FoxO4 in Jurkat T cells. Finally, we demonstrate that Tax represses FoxO4 transcriptional activity. Our study demonstrates that Tax can control FoxO4 protein stability and transcriptional activity and provides new insight into the subversion of cell signaling pathways during HTLV-1 infection.
Clathrin-Mediated Endocytosis in Living Host Cells Visualized through Quantum Dot Labeling of Infectious Hematopoietic Necrosis Virus
Authors: Liu Haibin , Liu Yi , Liu Shulin , Pang Dai-Wen , Xiao Gengfu 
Published: April 2011

ABSTRACT

Infectious hematopoietic necrosis virus (IHNV) is an important fish pathogen that infects both wild and cultured salmonids. As a species of the genus
Novirhabdovirus
, IHNV is a valuable model system for exploring the host entry mechanisms of rhabdoviruses. In this study, quantum dots (QDs) were used as fluorescent labels for sensitive, long-term tracking of IHNV entry. Using live-cell fluorescence microscopy, we found that IHNV is internalized through clathrin-coated pits after the virus binds to host cell membranes. Pretreatment of host cells with chlorpromazine, a drug that blocks clathrin-mediated endocytosis, and clathrin light chain (LCa) depletion using RNA interference both resulted in a marked reduction in viral entry. We also visualized transport of the virus via the cytoskeleton (i.e., actin filaments and microtubules) in real time. Actin polymerization is involved in the transport of endocytic vesicles into the cytosol, whereas microtubules are required for the trafficking of clathrin-coated vesicles to early endosomes, late endosomes, and lysosomes. Disrupting the host cell cytoskeleton with cytochalasin D or nocodazole significantly impaired IHNV infectivity. Furthermore, infection was significantly affected by pretreating the host cells with bafilomycin A1, a compound that inhibits the acidification of endosomes and lysosomes. Strong colocalizations of IHNV with endosomes indicated that the virus is internalized into these membrane-bound compartments. This is the first report in which QD labeling is used to visualize the dynamic interactions between viruses and endocytic structures; the results presented demonstrate that IHNV enters host cells via clathrin-mediated endocytic, cytoskeleton-dependent, and low-pH-dependent pathways.
Delayed Cytosolic Exposure of Japanese Encephalitis Virus Double-Stranded RNA Impedes Interferon Activation and Enhances Viral Dissemination in Porcine Cells
Authors: Espada-Murao Lyre Anni , Morita Kouichi 
Published: April 2011

ABSTRACTInterferon is a principal component of the host antiviral defense system. In this study, abortive focus formation by Japanese encephalitis virus (JEV) in primate cells was accompanied by early interferon induction, while productive focus formation in porcine cells was associated with a late interferon response. Neutralization antibodies against interferon relieved the restricted infection in primate cells, and increasingly larger foci were generated as treatment with exogenous interferon was delayed, thereby establishing a solid correlation between interferon response and viral dissemination. However, delayed interferon induction in JEV-infected porcine cells occurred in the absence of active inhibition by the virus. We further demonstrated that JEV mediates interferon activation through double-stranded RNA and cytosolic pattern recognition receptors. Immunofluorescence and subcellular fractionation studies revealed that double-stranded RNA is concealed in intracellular membranes at an early phase of infection but eventually appears in the cytosol at later periods, which could then allow detection by cytosolic pattern recognition receptors. Interestingly, cytosolic exposure of double-stranded RNA was delayed in porcine cells compared to primate cells, independent of total double-stranded RNA levels and in correlation with the timing of the interferon response. Furthermore, when double-stranded RNA was artificially introduced into the cytosol of porcine cells, more rapid and robust interferon activation was triggered than in viral infection. Thus, cytosolic exposure of JEV double-stranded RNA is imperative for interferon induction, but in cell lines (e.g., porcine cells) with delayed emergence of cytosolic double-stranded RNA, the interferon response is late and viral dissemination is consequently enhanced.
Crystal Structures of GII.10 and GII.12 Norovirus Protruding Domains in Complex with Histo-Blood Group Antigens Reveal Details for a Potential Site of Vulnerability
Authors: Hansman Grant S. , Biertümpfel Christian , Georgiev Ivelin , McLellan Jason S. , Chen Lei , Zhou Tongqing , Katayama Kazuhiko , Kwong Peter D. 
Published: April 2011

ABSTRACT
Noroviruses are the dominant cause of outbreaks of gastroenteritis worldwide, and interactions with human histo-blood group antigens (HBGAs) are thought to play a critical role in their entry mechanism. Structures of noroviruses from genogroups GI and GII in complex with HBGAs, however, reveal different modes of interaction. To gain insight into norovirus recognition of HBGAs, we determined crystal structures of norovirus protruding domains from two rarely detected GII genotypes, GII.10 and GII.12, alone and in complex with a panel of HBGAs, and analyzed structure-function implications related to conservation of the HBGA binding pocket. The GII.10- and GII.12-apo structures as well as the previously solved GII.4-apo structure resembled each other more closely than the GI.1-derived structure, and all three GII structures showed similar modes of HBGA recognition. The primary GII norovirus-HBGA interaction involved six hydrogen bonds between a terminal αfucose1-2 of the HBGAs and a dimeric capsid interface, which was composed of elements from two protruding subdomains. Norovirus interactions with other saccharide units of the HBGAs were variable and involved fewer hydrogen bonds. Sequence analysis revealed a site of GII norovirus sequence conservation to reside under the critical αfucose1-2 and to be one of the few patches of conserved residues on the outer virion-capsid surface. The site was smaller than that involved in full HBGA recognition, a consequence of variable recognition of peripheral saccharides. Despite this evasion tactic, the HBGA site of viral vulnerability may provide a viable target for small molecule- and antibody-mediated neutralization of GII norovirus.
Coxsackievirus B3-Induced Cellular Protrusions: Structural Characteristics and Functional Competence
Authors: Paloheimo Outi , Ihalainen Teemu O. , Tauriainen Sisko , Välilehto Outi , Kirjavainen Sanna , Niskanen Einari A. , Laakkonen Johanna P. , Hyöty Heikki , Vihinen-Ranta Maija 
Published: April 2011

ABSTRACT
Virus-induced alterations in cell morphology play important roles in the viral life cycle. To examine the intracellular events of coxsackievirus B3 (CVB3) infection, green monkey kidney (GMK) cells were either inoculated with the virus or transfected with the viral RNA. Various microscopic and flow cytometric approaches demonstrated the emergence of CVB3 capsid proteins at 8 h posttransfection, followed by morphological transformation of the cells. The morphological changes included formation of membranous protrusions containing viral capsids, together with microtubules and actin. Translocation of viral capsids into these protrusions was sensitive to cytochalasin D, suggesting the importance of actin in the process. Three-dimensional (3D) live-cell imaging demonstrated frequent contacts between cellular protrusions and adjacent cells. Markedly, in spite of an increase in the cellular viral protein content starting 8 h postinfection, no significant decrease in cell viability or increase in the amount of early apoptotic markers was observed by flow cytometry by 28 h postinfection. Comicroinjection of viral RNA and fluorescent dextran in the presence of neutralizing virus antibody suggested that these protrusions mediated the spread of infection from one cell to another prior to virus-induced cell lysis. Altogether, the CVB3-induced cellular protrusions could function as a hitherto-unknown nonlytic mechanism of cell-to-cell transmission exploited by enteroviruses.
Ambivalent Role of the Innate Immune Response in Rabies Virus Pathogenesis
Authors: Chopy Damien , Pothlichet Julien , Lafage Mireille , Mégret Françoise , Fiette Laurence , Si-Tahar Mustapha , Lafon Monique 
Published: April 2011

ABSTRACT

The neurotropic rabies virus (RABV) has developed several evasive strategies, including immunoevasion, to successfully infect the nervous system (NS) and trigger a fatal encephalomyelitis. Here we show that expression of LGP2, a protein known as either a positive or negative regulator of the RIG-I-mediated innate immune response, is restricted in the NS. We used a new transgenic mouse model (LGP2 TG) overexpressing LGP2 to impair the innate immune response to RABV and thus revealed the role of the RIG-I-mediated innate immune response in RABV pathogenesis. After infection, LGP2 TG mice exhibited reduced expression of inflammatory/chemoattractive molecules, beta interferon (IFN-β), and IFN-stimulated genes in their NS compared to wild-type (WT) mice, demonstrating the inhibitory function of LGP2 in the innate immune response to RABV. Surprisingly, LGP2 TG mice showed more viral clearance in the brain and lower morbidity than WT mice, indicating that the host innate immune response, paradoxically, favors RABV neuroinvasiveness and morbidity. LGP2 TG mice exhibited similar neutralizing antibodies and microglia activation to those of WT mice but showed a reduction of infiltrating CD4
+
T cells and less disappearance of infiltrating CD8
+
T cells. This occurred concomitantly with reduced neural expression of the IFN-inducible protein B7-H1, an immunoevasive protein involved in the elimination of infiltrated CD8
+
T cells. Our study shows that the host innate immune response favors the infiltration of T cells and, at the same time, promotes CD8
+
T cell elimination. Thus, to a certain extent, RABV exploits the innate immune response to develop its immunoevasive strategy.
Detection of Chronic Wasting Disease Prions in Salivary, Urinary, and Intestinal Tissues of Deer: Potential Mechanisms of Prion Shedding and Transmission
Authors: Haley Nicholas J. , Mathiason Candace K. , Carver Scott , Zabel Mark , Telling Glenn C. , Hoover Edward A. 
Published: April 2011

ABSTRACT

Efficient horizontal transmission is a signature trait of chronic wasting disease (CWD) in cervids. Infectious prions shed into excreta appear to play a key role in this facile transmission, as has been demonstrated by bioassays of cervid and transgenic species and serial protein misfolding cyclic amplification (sPMCA). However, the source(s) of infectious prions in these body fluids has yet to be identified. In the present study, we analyzed tissues proximate to saliva, urine, and fecal production by sPMCA in an attempt to elucidate this unique aspect of CWD pathogenesis. Oropharyngeal, urogenital, and gastrointestinal tissues along with blood and obex from CWD-exposed cervids (comprising 27 animals and >350 individual samples) were analyzed and scored based on the apparent relative CWD burden. PrP
CWD
-generating activity was detected in a range of tissues and was highest in the salivary gland, urinary bladder, and distal intestinal tract. In the same assays, blood from the same animals and unseeded normal brain homogenate controls (
n
= 116 of 117) remained negative. The PrP-converting activity in peripheral tissues varied from 10
−11
- to 10
0
-fold of that found in brain of the same animal. Deer with highest levels of PrP
CWD
amplification in the brain had higher and more widely disseminated prion amplification in excretory tissues. Interestingly, PrP
CWD
was not demonstrable in these excretory tissues by conventional Western blotting, suggesting a low prion burden or the presence of protease-sensitive infectious prions destroyed by harsh proteolytic treatments. These findings offer unique insights into the transmission of CWD in particular and prion infection and trafficking overall.