Analyses of intestinal biopsies of infected individuals and/or nonhuman primates (NHP) suggested the possible immune cell tropism of human noroviruses (HuNoV) and rhesus enteric caliciviruses (ReCV). Subsequently, the first HuNoV cell culture system using human B cell lines was reported. However, reproducibility issues raised questions about the validity and suitability of B cell cultures for HuNoV research.
View Article and Find Full Text PDFRecently, using a panel of recombinant CHO cell lines, we identified the coxsackie and adenovirus receptor (CAR) and histo-blood group antigens (HBGAs) or sialic acid as the minimum requirement for susceptibility to rhesus enteric calicivirus (ReCV) infections. While ReCVs cause lytic infection in LLC-MK2 cells, recombinant CHO (rCHO) cell lines did not exhibit any morphological changes upon infection. To monitor infectious virus production, rCHO cell cultures had to be freeze-thawed and titrated on LLC-MK2 monolayers.
View Article and Find Full Text PDFUsing bibliometric analysis of large-scale publication data is a simple approach to exploring gender-related trends, especially gender equality in academic publishing. The aim of this study is to investigate gender trends in the fields of bio-economy and rural development sciences in two under develop regions as Latin America and Africa. This study examines gender differences in these fields in order to: (1) recognize the contribution of female researchers in bioeconomy and rural development, (2) explore the relational structure of gender aspects in academic publications, (3) identify trends in female authorship in these scientific research fields over time, and finally (4) identify gender potentials for women to become more visible in these fields of study.
View Article and Find Full Text PDFComparative bioavailability studies often involve multiple groups of subjects for a variety of reasons, such as clinical capacity limitations. This raises questions about the validity of pooling data from these groups in the statistical analysis and whether a group-by-treatment interaction should be evaluated. We investigated the presence or absence of group-by-treatment interactions through both simulation techniques and a meta-study of well-controlled trials.
View Article and Find Full Text PDFRecently, we identified the coxsackie and adenovirus receptor (CAR) as the entry receptor for rhesus enteric calicivirus (ReCV) isolate FT285 and demonstrated that co-expression of the CAR and the type B histo-blood group antigen (HBGA) is required to convert the resistant CHO cell line susceptible to infection. To address whether the CAR is also the functional entry receptor for other ReCV isolates and the requirement for specific HBGAs or other glycans, here we used a panel of recombinant CHO cell lines expressing the CAR and the type A, B, or H HBGAs alone or in combination. Infection studies with three diverse ReCV strains, the prototype GI.
View Article and Find Full Text PDFAlthough detailed descriptions of proper handshakes partly comprise many etiquette books, how a normal handshake can be described, its proper duration, and the consequences of violating handshake expectations remain empirically unexplored. This study measured the effect of temporal violations of the expected length of a handshake (less than three seconds according to previous studies) administered unobtrusively in a naturalistic experiment. We compared volunteer participants' ( = 34; 25 females; 9 males; = 23.
View Article and Find Full Text PDFEnteric viruses in the family cause acute gastroenteritis in humans and animals, but the cellular processes needed for virus replication and disease remain unknown. A common strategy among enteric viruses, including rotaviruses and enteroviruses, is to encode a viral ion channel (i.e.
View Article and Find Full Text PDFHuman norovirus (HuNoV) is a leading cause of acute gastroenteritis in both developed and developing countries. Studies of HuNoV host cell interactions are limited by the lack of a simple, robust cell culture system. Due to their diverse HuNoV-like biological features, including histo-blood group antigen (HBGA) binding, rhesus enteric caliciviruses (ReCVs) are viable surrogate models for HuNoVs.
View Article and Find Full Text PDFAntimicrob Agents Chemother
November 2016
Two A/C incompatibility group (IncA/C family) plasmids from the 1960s have been sequenced and classified into the A/C type 1 group. R16a and IP40a contain novel antibiotic resistance islands and a complete GIsul2 genomic island not previously found in the family. In the 173.
View Article and Find Full Text PDFUsing a recently developed real-time reverse transcription PCR, I retested 500 fecal samples from rhesus macaques collected in 2008. Previous conventional reverse transcription PCR testing identified 1 isolate of GII norovirus; retesting found GI, GII, and possible GIV noroviruses in the samples, indicating the natural circulation of noroviruses in nonhuman primate colonies.
View Article and Find Full Text PDFNoroviruses are important causes of acute gastroenteritis and are classified into six genogroups with GI, GII and GIV containing human pathogens. This high genetic diversity represents a significant challenge for diagnostic assay development. Genogroup specific monoplex and multiplex real time RT-PCR assays are widely used for the detection of GI and GII noroviruses.
View Article and Find Full Text PDFThe genomic island SGI1 and its variants, the important vehicles of multi-resistance in Salmonella strains, are integrative elements mobilized exclusively by the conjugative IncA/C plasmids. Integration and excision of the island are carried out by the SGI1-encoded site-specific recombinase Int and the recombination directionality factor Xis. Chromosomal integration ensures the stable maintenance and vertical transmission of SGI1, while excision is the initial step of horizontal transfer, followed by conjugation and integration into the recipient.
View Article and Find Full Text PDFAppl Environ Microbiol
August 2015
Oyster contamination by noroviruses is an important health and economic problem. The present study aimed to compare the behaviors of Norwalk virus (the prototype genogroup I norovirus) and two culturable viruses: Tulane virus and mengovirus. After bioaccumulation, tissue distributions were quite similar for Norwalk virus and Tulane virus, with the majority of viral particles detected in digestive tissues, while mengovirus was detected in large amounts in the gills and mantle as well as in digestive tissues.
View Article and Find Full Text PDFAppl Environ Microbiol
August 2015
Human norovirus (HuNoV) is the leading cause of foodborne illnesses, with an increasing number of outbreaks associated with leafy greens. Because HuNoV cannot be routinely cultured, culturable feline calicivirus (FCV), murine norovirus (MNV), porcine sapovirus (SaV), and Tulane virus (TV) have been used as surrogates. These viruses are generated in different cell lines as infected cell lysates, which may differentially affect their stability.
View Article and Find Full Text PDFJ Gen Virol
July 2015
Human noroviruses are one of the major causes of acute gastroenteritis worldwide. Due to the lack of an efficient human norovirus cell culture system coupled with an animal model, human norovirus research mainly relies on human volunteer studies and surrogate models. Current models either utilize human norovirus-infected animals including the gnotobiotic pig or calf and the chimpanzee models, or employ other members of the family Caliciviridae including cell culture propagable surrogate caliciviruses such as the feline calicivirus, murine norovirus and most recently the Tulane virus.
View Article and Find Full Text PDFArch Virol
December 2014
Canonical human astroviruses (HAstVs) are important enteric pathogens that can be classified genetically and antigenically into eight types. Sequence analysis of small diagnostic regions at either the 5' or 3' end of ORF2 (capsid precursor) is a good proxy for prediction of HAstV types and for distinction of intratypic genetic lineages (subtypes), although lineage diversification/classification has not been investigated systematically. Upon sequence and phylogenetic analysis of the full-length ORF2 of 86 HAstV strains selected from the databases, a detailed classification of HAstVs into lineages was established.
View Article and Find Full Text PDFAppl Environ Microbiol
September 2014
Human norovirus is the leading cause of epidemic and sporadic acute gastroenteritis. Since no cell culture method for human norovirus exists, cultivable surrogate viruses (CSV), including feline calicivirus (FCV), murine norovirus (MNV), porcine enteric calicivirus (PEC), and Tulane virus (TuV), have been used to study responses to inactivation and disinfection methods. We compared the levels of reduction in infectivities of CSV and Aichi virus (AiV) after exposure to extreme pHs, 56°C heating, alcohols, chlorine on surfaces, and high hydrostatic pressure (HHP), using the same matrix and identical test parameters for all viruses, as well as the reduction of human norovirus RNA levels under these conditions.
View Article and Find Full Text PDFJ Clin Microbiol
August 2014
To investigate recovirus infections and their association with zoonosis, the prevalence of the virus-neutralizing antibody against three recovirus serotypes was tested in the general population and in zookeepers. Neutralizing antibodies were detected in a significantly higher number of zookeepers than in the general population but with significantly lower titers than in macaques.
View Article and Find Full Text PDFHuman norovirus (NoV) research greatly relies on cell culture-propagable surrogate caliciviruses, including murine NoVs and the prototype 'recovirus' (ReCV), Tulane virus. However, the extreme biological diversity of human NoVs cannot be modelled by a uniform group of viruses or single isolate. Based on a diverse group of recently described ReCVs, a more advanced model reflecting human NoV biological diversity is currently under development.
View Article and Find Full Text PDFPooled fecal specimens collected from striped field mice (Apodemus agrarius), yellow-necked mice (Apodemus flavicollis), and bank voles (Myodes glareolus) and individual stool samples collected from laboratory mice were tested for the presence of picornaviruses and astroviruses. Picornavirus RNA was detected only in one striped field mouse sample pool, while astrovirus RNA was detected in two yellow-necked mouse sample pools and in six of the 121 laboratory mouse samples. In a 234-amino acid (aa) fragment of the viral RNA dependent RNA polymerase (RdRp), the wild mouse picornavirus revealed the closest homology to the canyon mouse (Peromyscus crinitus) (93 % aa) and canine kobuviruses (92 % aa) and to Aichi virus (88 % aa).
View Article and Find Full Text PDFBackground: The rhesus enteric caliciviruses (ReCVs) were recently described.
Methods: Prevalence of ReCV antibodies was tested in six species of captive non-human primates.
Results: High ReCV seroprevalence was revealed in rhesus and cynomolgus macaques.
Fecal specimens collected from 121 laboratory mice, 30 striped field mice (Apodemus agrarius), 70 yellow-necked mice (Apodemus flavicollis), and 3 bank voles (Myodes glareolus) were tested in sample pools for the presence of murine noroviruses (MNV). Ten of 41 laboratory mice and 2 of 3 striped field mice pooled samples were positive for MNV. All laboratory mouse MNVs were closely related to previously described MNVs.
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