bluuebunny/crossref_metadata_2025_split huggingface dataset:
High Frequency of Repeated Infections Due to Emerging Genotypes of Human Respiratory Syncytial Viruses among Children during Eight Successive Epidemic Seasons in Japan
Authors: Yamaguchi Masahiro , Sano Yasuko , Dapat Isolde C. , Saito Reiko , Suzuki Yasushi , Kumaki Akihiko , Shobugawa Yugo , Dapat Clyde , Uchiyama Makoto , Suzuki Hiroshi 
Published: December 2010

ABSTRACT

In eight successive seasons (2001 to 2009), a total of 726 human respiratory syncytial virus (HRSV) infections from a total of 1,560 children with acute lower respiratory tract illness were identified. Molecular analysis of the attachment (G) protein gene confirmed that 52 (7.8%) children were infected more than once with any of the 3 genotypes of HRSV-A (genotypes GA5, NA1, and NA2) and/or 6 genotypes of HRSV-B (genotypes BA4, BA5, and BA7 to BA10). Repeated infections in 46 cases (82.1%) occurred in the next season, and only one case occurred in the same season (10-day interval). First infections were 33 (63.5%) HRSV-A cases and 19 (36.5%) HRSV-B cases, whereas second infections occurred in 35 (67.3%) HRSV-A cases and 17 (32.7%) HRSV-B cases. Third infections were attributed to 4 (100.0%) HRSV-A cases. Homologous subgroup reinfections were detected in 28 cases, 23 HRSV-A cases and 5 HRSV-B cases (
P
= 0.005), whereas homologous genotype reinfections were detected only for 5 HRSV-A cases (2GA5 and 3NA2) but not any HRSV-B case. Heterologous subgroup reinfections were detected in 28 cases, 12 cases from HRSV-A-to-HRSV-B reinfections and 16 cases from HRSV-B-to-HRSV-A reinfections. Genotypes NA1 and NA2 had higher numbers of heterologous genotype infections than did other genotypes. Our observations suggest that repeated infections occur more frequently in HRSV-A strains than in HRSV-B strains, and heterologous genotype reinfections occur more frequently than homologous genotype reinfections, especially in the case of the emerging genotypes NA1 and NA2 of HRSV-A strains that circulated in the community during our study period.
Characteristics of Cryptosporidium Transmission in Preweaned Dairy Cattle in Henan, China
Authors: Wang Rongjun , Wang Helei , Sun Yanru , Zhang Longxian , Jian Fuchun , Qi Meng , Ning Changshen , Xiao Lihua 
Published: December 2010

ABSTRACT

To estimate the prevalence and public health significance of cryptosporidiosis in preweaned calves in China, 801 fecal samples from eight farms in seven areas in Henan Province were examined for
Cryptosporidium
oocysts. The overall infection rate of
Cryptosporidium
was 21.5%, with the farm in Xinxiang having the highest prevalence (40%). No significant difference in infection rates was observed between seasons.
Cryptosporidium
spp. were characterized by PCR-restriction fragment length polymorphism (RFLP) analysis of the small subunit (SSU) rRNA gene and DNA sequencing of the 60-kDa glycoprotein (gp60) gene. The SSU rRNA-based PCR identified four
Cryptosporidium
species, including
Cryptosporidium parvum
(54/172),
C. bovis
(65/172),
C. ryanae
(19/172), and
C. andersoni
(12/172), and the occurrence of infections with mixed species (22/172). The earliest detection of
C. bovis
was in calves of 1 week of age, showing that the prepatent period was shorter than the previously stated 10 to 12 days. Infections with
C. parvum
peaked in summer, whereas
C. bovis
dominated in autumn and winter. There was no apparent difference in the age of cattle infected with either
C. parvum
or
C. bovis
. Sequencing analysis of the gp60 gene showed all 67
C. parvum
samples belonged to subtype IIdA19G1. These findings suggested that the transmission of
Cryptosporidium
spp. in preweaned calves in Henan, China, appeared to be different from other areas both at genotype and subtype levels. Further molecular epidemiologic studies (including samples from both calves and humans) are needed to elucidate the transmission dynamics and public significance of
C. parvum
in cattle in China.
Efficient Differentiation of Mycobacterium abscessus Complex Isolates to the Species Level by a Novel PCR-Based Variable-Number Tandem-Repeat Assay
Authors: Choi Go-Eun , Chang Chulhun L. , Whang Jake , Kim Hwa-Jung , Kwon O. Jung , Koh Won-Jung , Shin Sung Jae 
Published: December 2010

ABSTRACT

A novel duplex PCR method based on variable-number tandem-repeat targets to discriminate among
Mycobacterium abscessus
complex isolates was developed and evaluated in 85 clinical isolates. The assay accuracy was confirmed by a multiple-target sequence analysis. The duplex PCR assay is a one-step, reliable, and accurate assay for discriminating
M. abscessus
species.
Role of the Clinical Mycobacteriology Laboratory in Diagnosis and Management of Tuberculosis in Low-Prevalence Settings
Authors: Parrish Nicole M. , Carroll Karen C. 
Published: December 2010

ABSTRACT

Tuberculosis (TB) remains a global epidemic, despite a significant decline in reported cases in the United States between 2008 and 2009. While the exact nature of this decline is unclear, one thing remains certain: TB, including multidrug-resistant (MDR) and extensively drug-resistant (XDR) TB, is no longer restricted to developing regions of the globe. It is of vital importance that both public and private mycobacteriology laboratories maintain the ability to detect and identify
Mycobacterium tuberculosis
from patient specimens, as well as correctly determine the presence of antibiotic resistance. To do this effectively requires careful attention to preanalytical, analytical, and postanalytical aspects of testing. Respiratory specimens require digestion and concentration followed by fluorescence microscopy. The Centers for Disease Control and Prevention (CDC) recommends the performance of a direct nucleic acid amplification method, regardless of smear results, on specimens from patients in whom the suspicion of tuberculosis is high. Liquid-based technologies are more rapid and sensitive for the detection of
M. tuberculosis
in culture and nucleic acid probes, but biochemicals are preferred for identification once growth is detected. Susceptibility testing is most often done using either the agar proportion method or a commercial broth system. New genotypic and phenotypic methods of susceptibility testing include first- and second-line agents and are promising, though not yet widely available. Finally, gamma interferon release assays are preferred to the tuberculin skin test for screening certain at-risk populations, and new CDC guidelines are available that assist clinicians in their use.
Diagnostic Performance of Filter Paper Lesion Impression PCR for Secondarily Infected Ulcers and Nonulcerative Lesions Caused by Cutaneous Leishmaniasis
Authors: Boggild Andrea K. , Ramos Ana Pilar , Valencia Braulio Mark , Veland Nicolas , Calderon Flor , Arevalo Jorge , Low Donald E. , Llanos-Cuentas Alejandro 
Published: December 2010

ABSTRACT

We compared traditional cutaneous leishmaniasis diagnostic methods to filter paper lesion impression (FPLI) PCR for secondarily infected ulcers and nonulcerative lesions. The sensitivity and specificity of FPLI PCR for secondarily infected lesions (
n
= 8) were 100%. In primarily nonulcerative lesions (
n
= 15), the sensitivity of FPLI PCR was inferior to that of pooled-invasive-specimen PCR (72.7% versus 100%) (
P
= 0.10). FPLI PCR is sensitive, specific, and unlike invasive procedures, can be used in secondarily infected ulcers. Invasive specimen collection is superior in nonulcerative lesions.
Diversity of Interferon Antagonist Activities Mediated by NSP1 Proteins of Different Rotavirus Strains
Authors: Arnold Michelle M. , Patton John T. 
Published: December 2010

ABSTRACTStudies involving limited numbers of rotavirus (RV) strains have shown that the viral gene 5 product, NSP1, can antagonize beta interferon (IFN-β) expression by inducing the degradation of IFN-regulatory factors (IRFs) (IRF3, IRF5, and IRF7) or a component of the E3 ubiquitin ligase complex responsible for activating NF-κB (β-transducin repeat-containing protein [β-TrCP]). To gain a broader perspective of NSP1 activities, we examined various RV strains for the ability to inhibit IFN-β expression in human cells. We found that all strains encoding wild-type NSP1 impeded IFN-β expression but not always through IRF3 degradation. To identify other degradation targets involved in suppressing IFN-β expression, we used transient expression vectors to test the abilities of a diverse collection of NSP1 proteins to target IRF3, IRF5, IRF7, and β-TrCP for degradation. The results indicated that human RVs rely predominantly on the NSP1-induced degradation of IRF5 and IRF7 to suppress IFN signaling, whereas NSP1 proteins of animal RVs tended to target IRF3, IRF5, and IRF7, allowing the animal viruses a broader attack on the IFN-β signaling pathway. The results also suggested that the NSP1-induced degradation of β-TrCP is an uncommon mechanism of subverting IFN-β signaling but is one that can be shared with NSP1 proteins that induce IRF degradation. Our analysis reveals that the activities of NSP1 proteins are diverse, with no obvious correlations between degradations of pairs of target proteins. Thus, RVs have evolved functionally distinct approaches for subverting the host antiviral response, a property consistent with the immense sequence variation noted for NSP1 proteins.
Tupaia CD81, SR-BI, Claudin-1, and Occludin Support Hepatitis C Virus Infection
Authors: Tong Yimin , Zhu Yongzhe , Xia Xueshan , Liu Yuan , Feng Yue , Hua Xian , Chen Zhihui , Ding Hui , Gao Li , Wang Yongzhi , Feitelson Mark A. , Zhao Ping , Qi Zhong-Tian 
Published: December 2010

ABSTRACTHepatitis C virus (HCV)-related research has been hampered by the lack of appropriate small-animal models. It has been reported that tree shrews, or tupaias (Tupaia belangeri), can be infected with serum-derived HCV. However, these reports do not firmly establish the tupaia as a reliable model of HCV infection. Human CD81, scavenger receptor class B type I (SR-BI), claudin 1 (CLDN1), and occludin (OCLN) are considered essential receptors or coreceptors for HCV cell entry. In the present study, the roles of these tupaia orthologs in HCV infection were assessed. Both CD81 and SR-BI of tupaia were found to be able to bind with HCV envelope protein 2 (E2). In comparison with human CD81, tupaia CD81 exhibited stronger binding activity with E2 and increased HCV pseudoparticle (HCVpp) cell entry 2-fold. The 293T cells transfected with tupaia CLDN1 became susceptible to HCVpp infection. Moreover, simultaneous transfection of the four tupaia factors into mouse NIH 3T3 cells made the cells susceptible to HCVpp infection. HCVpp of diverse genotypes were able to infect primary tupaia hepatocytes (PTHs), and this infection could be blocked by either anti-CD81 or anti-SR-BI. PTHs could be infected by cell culture-produced HCV (HCVcc) and did produce infectious progeny virus in culture supernatant. These findings indicate that PTHs possess all of the essential factors required for HCV entry and support the complete HCV infection cycle. This highlights both the mechanisms of susceptibility of tupaia to HCV infection and the possibility of using tupaia as a promising small-animal model in HCV study.
Transcriptional Profiling of CD4 T Cells Identifies Distinct Subgroups of HIV-1 Elite Controllers
Authors: Vigneault Francois , Woods Matthew , Buzon Maria J. , Li Chun , Pereyra Florencia , Crosby Seth D. , Rychert Jennifer , Church George , Martinez-Picado Javier , Rosenberg Eric S. , Telenti Amalio , Yu Xu G. , Lichterfeld Mathias 
Published: December 2010

ABSTRACT

Human immunodeficiency virus type 1 (HIV-1) elite controllers maintain undetectable levels of viral replication in the absence of antiretroviral therapy (ART), but their underlying immunological and virological characteristics may vary. Here, we used a whole-genome transcriptional profiling approach to characterize gene expression signatures of CD4 T cells from an unselected cohort of elite controllers. The transcriptional profiles for the majority of elite controllers were similar to those of ART-treated patients but different from those of HIV-1-negative persons. Yet, a smaller proportion of elite controllers showed an alternative gene expression pattern that was indistinguishable from that of HIV-1-negative persons but different from that of highly active antiretroviral therapy (HAART)-treated individuals. Elite controllers with the latter gene expression signature had significantly higher CD4 T cell counts and lower levels of HIV-1-specific CD8
+
T cell responses but did not significantly differ from other elite controllers in terms of HLA class I alleles, HIV-1 viral loads determined by ultrasensitive single-copy PCR assays, or chemokine receptor polymorphisms. Thus, these data identify a specific subgroup of elite controllers whose immunological and gene expression characteristics approximate those of HIV-1-negative persons.
Complementing Defective Viruses That Express Separate Paramyxovirus Glycoproteins Provide a New Vaccine Vector Approach
Authors: Chattopadhyay Anasuya , Rose John K. 
Published: December 2010

ABSTRACTReplication-defective vaccine vectors based on vesicular stomatitis virus (VSV) lacking its envelope glycoprotein gene (G) are highly effective in animal models. However, such ΔG vectors are difficult to grow because they require complementation with the VSV G protein. In addition, the complementing G protein induces neutralizing antibodies in animals and thus limits multiple vector applications. In the process of generating an experimental Nipah virus (a paramyxovirus) vaccine, we generated two defective VSVΔG vectors, each expressing one of the two Nipah virus (NiV) glycoproteins (G and F) that are both required for virus entry to host cells. These replication-defective VSV vectors were effective at generating NiV neutralizing antibody in mice. Most interestingly, we found that these two defective viruses could be grown together and passaged in tissue culture cells in the absence of VSV G complementation. This mixture of complementing defective viruses was also highly effective at generating NiV neutralizing antibody in animals. This novel approach to growing and producing a vaccine from two defective viruses could be generally applicable to vaccine production for other paramyxoviruses or for other viruses where the expression of at least two different proteins is required for viral entry. Such an approach minimizes biosafety concerns that could apply to single, replication-competent VSV recombinants expressing all proteins required for infection.
Varicella-Zoster Virus Transcriptome in Latently Infected Human Ganglia
Authors: Nagel Maria A. , Choe Alexander , Traktinskiy Igor , Cordery-Cotter Robert , Gilden Don , Cohrs Randall J. 
Published: December 2010

ABSTRACT

We recently developed a novel multiplex reverse transcription (RT)-PCR assay that allows rapid and sensitive detection of transcripts corresponding to all 68 unique varicella-zoster virus (VZV) open reading frames (ORFs) in only five amplification reactions (M. A. Nagel, D. Gilden, T. Shade, B. Gao, and R. J. Cohrs, J. Virol. Methods
157:
62-68, 2009). Herein, we applied multiplex RT-PCR analysis to mRNA extracted from 26 trigeminal ganglia latently infected with VZV and one control trigeminal ganglion negative for VZV DNA that were removed from 14 men and women, 16 to 84 years of age, within 24 h after death. Analysis identified VZV transcripts mapping to VZV ORFs 29, 62, and 63, previously detected and sequence verified; VZV ORFs 4 and 40, previously detected by
in situ
hybridization; and VZV ORFs 11, 41, 43, 57, and 68, not previously detected. VZV ORF 63 transcripts were the most prevalent. Comparison of the 10 VZV ORFs transcribed during latency to their herpes simplex virus type 1 homologues reveals that the latently transcribed VZV genes encode immediate-early, early, and late transcripts.
Structural Flexibility Allows the Functional Diversity of Potyvirus Genome-Linked Protein VPg
Authors: Rantalainen Kimmo I. , Eskelin Katri , Tompa Peter , Mäkinen Kristiina 
Published: December 2010

ABSTRACTSeveral viral genome-linked proteins (VPgs) of plant viruses are intrinsically disordered and undergo folding transitions in the presence of partners. This property has been postulated to be one of the factors that enable the functional diversity of the protein. We created a homology model ofPotato virus AVPg and positioned the known functions and structural properties of potyviral VPgs on the novel structural model. The model suggests an elongated structure with a hydrophobic core composed of antiparallel β-sheets surrounded by helices and a positively charged contact surface where most of the known activities are localized. The model most probably represents the fold induced immediately after binding of VPg to a negatively charged lipid surface or to SDS. When the charge of the positive surface was lowered by lysine mutations, the efficiencies ofin vitroNTP binding, uridylylation reaction, and unspecific RNA binding were reduced andin vivothe infectivity was debilitated. The most likely uridylylation site, Tyr63, locates to the positively charged surface. Surprisingly, a Tyr63Ala mutation did not prevent replication completely but blocked spreading of the virus. Based on the localization of Tyr119 in the model, it was hypothesized to serve as an alternative uridylylation site. Evidence to support the role of Tyr119 in replication was obtained which gives a positive example of the prediction power of the model. Taken together, our experimental data support the features presented in the model and the idea that the functional diversity is attributable to structural flexibility.
Orf Virus
ORFV121
Encodes a Novel Inhibitor of NF-κB That Contributes to Virus Virulence
Authors: Diel D. G. , Luo S. , Delhon G. , Peng Y. , Flores E. F. , Rock D. L. 
Published: December 2010

ABSTRACT

Orf virus (ORFV), the type member of the genus
Parapoxvirus
of the
Poxviridae
, has evolved novel strategies (proteins and/or mechanisms of action) to modulate host cell responses regulated by the nuclear factor-κB (NF-κB) signaling pathway. Here, we present data indicating that ORFV
ORFV121
, a gene unique to parapoxviruses, encodes a novel viral NF-κB inhibitor that binds to and inhibits the phosphorylation and nuclear translocation of NF-κB-p65. The infection of cells with an
ORFV121
deletion mutant virus (OV-IA82Δ121) resulted in increased NF-κB-mediated gene transcription, and the expression of ORFV121 in cell cultures significantly suppressed NF-κB-regulated reporter gene expression. ORFV ORFV121 physically interacts with NF-κB-p65 in the cell cytoplasm, thus providing a mechanism for the inhibition of NF-κB-p65 phosphorylation and nuclear translocation. Notably, the deletion of
ORFV121
from the viral genome markedly decreased ORFV virulence and disease pathogenesis in sheep, indicating that ORFV121 is a virulence determinant for ORFV in the natural host.
EBNA3C Attenuates the Function of p53 through Interaction with Inhibitor of Growth Family Proteins 4 and 5
Authors: Saha Abhik , Bamidele Adebowale , Murakami Masanao , Robertson Erle S. 
Published: December 2010

ABSTRACT

Epstein-Barr virus (EBV)-encoded EBNA3C is one of the latent proteins essential for the efficient transformation of human primary B lymphocytes into continuously proliferating lymphoblastoid cell lines (LCLs)
in vitro
through manipulation of a number of major cellular pathways. Although it does not have direct DNA-binding activity, EBNA3C plays a central role in the transcriptional modulation of a wide range of both viral and cellular genes during latent infection. Recently, we showed that EBNA3C can directly bind to the tumor suppressor protein p53 and repress its functions, in part by blocking its transcriptional activity as well as facilitating its degradation through stabilization of its negative regulator, Mdm2. In this study, we further showed that EBNA3C can negatively regulate p53-mediated functions by interacting with its regulatory proteins, the inhibitor of growth family proteins ING4 and ING5, shown to be frequently deregulated in different cancers. Functional mapping revealed that both ING4 and ING5 bound to N-terminal domain residues 129 to 200 of EBNA3C, which was previously demonstrated to associate with p53 and is also essential for LCL growth. In addition, we showed that a conserved domain of either ING4 or ING5 bound to both p53 and EBNA3C in a competitive manner, suggesting a potential role for EBNA3C whereby the ING4 or -5/p53 pathway is modulated in EBV-infected cells. Subsequently, we demonstrated that EBNA3C significantly suppresses both the ING4- and ING5-mediated regulation of p53 transcriptional activity in a dose-dependent manner. A colony formation assay as well as an apoptosis assay showed that EBNA3C nullified the negative regulatory effects on cell proliferation induced by coupled expression of p53 in the presence of either ING4 or ING5 in Saos-2 (p53
−/−
) cells. This report demonstrates a possible role for the candidate tumor suppressor ING genes in the biology of EBV-associated cancers.
VEGFR2 and Src Kinase Inhibitors Suppress Andes Virus-Induced Endothelial Cell Permeability
Authors: Gorbunova Elena E. , Gavrilovskaya Irina N. , Pepini Timothy , Mackow Erich R. 
Published: December 2010

ABSTRACTHantaviruses predominantly infect human endothelial cells and, in the absence of cell lysis, cause two diseases resulting from increased vascular permeability. Andes virus (ANDV) causes a highly lethal acute pulmonary edema termed hantavirus pulmonary syndrome (HPS). ANDV infection enhances the permeability of endothelial cells in response to vascular endothelial growth factor (VEGF) by increasing signaling responses directed by the VEGFR2-Src-VE-cadherin pathway, which directs adherens junction (AJ) disassembly. Here we demonstrate that inhibiting pathway-specific VEGFR2 and Src family kinases (SFKs) blocks ANDV-induced endothelial cell permeability. Small interfering RNA (siRNA) knockdown of Src within ANDV-infected endothelial cells resulted in an ∼70% decrease in endothelial cell permeability compared to that for siRNA controls. This finding suggested that existing FDA-approved small-molecule kinase inhibitors might similarly block ANDV-induced permeability. The VEGFR2 kinase inhibitor pazopanib as well as SFK inhibitors dasatinib, PP1, bosutinib, and Src inhibitor 1 dramatically inhibited ANDV-induced endothelial cell permeability. Consistent with their kinase-inhibitory concentrations, dasatinib, PP1, and pazopanib inhibited ANDV-induced permeability at 1, 10, and 100 nanomolar 50% inhibitory concentrations (IC50s), respectively. We further demonstrated that dasatinib and pazopanib blocked VE-cadherin dissociation from the AJs of ANDV-infected endothelial cells by >90%. These findings indicate that VEGFR2 and Src kinases are potential targets for therapeutically reducing ANDV-induced endothelial cell permeability and, as a result, capillary permeability during HPS. Since the functions of VEGFR2 and SFK inhibitors are already well defined and FDA approved for clinical use, these findings rationalize their therapeutic evaluation for efficacy in reducing HPS disease. Endothelial cell barrier functions are disrupted by a number of viruses that cause hemorrhagic, edematous, or neurologic disease, and as a result, our findings suggest that VEGFR2 and SFK inhibitors should be considered for regulating endothelial cell barrier functions altered by additional viral pathogens.