Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0017160 (gastroenteritis)
 11,398 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Noroviruses (NoVs) belong to the genus Norovirus and are members of the family Caliciviridae. NoVs are the dominant cause of outbreaks of gastroenteritis, but progress in understanding the molecular characteristics of NoV and its replication strategies have been hampered by the lack of a cell culture system or a practical animal model, except for murine NoVs. To elucidate the transcription and replication of the NoV genome, a complete genome of a human NoV genogroup II strain was cloned downstream of a T7 RNA polymerase promoter and expressed in human embryonic kidney (HEK) 293T/17 cells using a T7 vaccinia virus expression system. Bands for a 7.6-kb negative-strand RNA, a 7.6-kb positive-strand genomic RNA, and a 2.6-kb positive-strand subgenomic-like RNA were found in the infected cells. However, recombinant capsid protein (rVP1) and rVP2 were not detected by Western blotting. When a construct containing VP1 and VP2 genes was co-transfected with a full-length construct, the expression of virus-like particles (VLPs) with a buoyant density of 1.271 g/cm3 was observed. We also observed round particles, 20 to 80 nm in diameter, with a buoyant density of 1.318 g/cm3. Our results indicated that NoV RNA was incorporated into the heavier particles. However, further studies are needed to investigate the antigenicity of these particles and to determine if they represent undeveloped VLPs.
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PMID:Investigation of norovirus replication in a human cell line. 1650 84

The Belgian rotavirus strain B4106, isolated from a child with gastroenteritis, was previously found to have VP7 (G3), VP4 (P[14]), and NSP4 (A genotype) genes closely related to those of lapine rotaviruses, suggesting a possible lapine origin or natural reassortment of strain B4106. To investigate the origin of this unusual strain, the gene sequences encoding VP1, VP2, VP3, VP6, NSP1, NSP2, NSP3, and NSP5/6 were also determined. To allow comparison to a lapine strain, the 11 double-stranded RNA segments of a European G3P[14] rabbit rotavirus strain 30/96 were also determined. The complete genome similarity between strains B4106 and 30/96 was 93.4% at the nucleotide level and 96.9% at the amino acid level. All 11 genome segments of strain B4106 were closely related to those of lapine rotaviruses and clustered with the lapine strains in phylogenetic analyses. In addition, sequence analyses of the NSP5 gene of strain B4106 revealed that the altered electrophoretic mobility of NSP5, resulting in a super-short pattern, was due to a gene rearrangement (head-to-tail partial duplication, combined with two short insertions and a deletion). Altogether, these findings confirm that a rotavirus strain with an entirely lapine genome complement was able to infect and cause severe disease in a human child.
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PMID:Full genomic analysis of human rotavirus strain B4106 and lapine rotavirus strain 30/96 provides evidence for interspecies transmission. 1657 97

Rotavirus (RV) is the main etiological agent of severe gastroenteritis in infants, and vaccination seems the most effective way to control the disease. Recombinant rotavirus-like particles composed of the viral protein 6 (VP6) and VP2 (2/6-VLPs) have been reported to induce protective immunity in mice when administered by the intranasal (i.n.) route. In this study, we show that administration of 2/6-VLPs by the intrarectal (i.r.) route together with either cholera toxin (CT) or a CpG-containing oligodeoxynucleotide as the adjuvant protects adult mice against RV infection. Moreover, when CT is used, RV shedding in animals immunized by the i.r. route is even reduced in comparison with that in animals immunized by the i.n. route. Humoral and cellular immune responses induced by these immunization protocols were analyzed. We found that although i.r. immunization with 2/6-VLPs induces lower RV-specific immunoglobulin G (IgG) and IgA levels in serum, intestinal anti-RV IgA production is higher in mice immunized by the i.r. route. Cellular immune response has been evaluated by measuring cytokine production by spleen and Peyer's patch cells (PPs) after ex vivo restimulation with RV. Mice immunized by the i.n. and i.r. routes display higher gamma interferon production in spleen and PPs, respectively. In conclusion, we demonstrate that i.r. immunization with 2/6-VLPs protects against RV infection in mice and is more efficient than i.n. immunization in inducing an anti-RV immune response in intestinal mucosa.
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PMID:Intrarectal immunization with rotavirus 2/6 virus-like particles induces an antirotavirus immune response localized in the intestinal mucosa and protects against rotavirus infection in mice. 1657 99

Long RNA electropherotype rotavirus strains with subgroup I specificity predominated the infantile gastroenteritis outbreak in Manipur, India, in 1987-88. One such strain (RMC321) was found to possess porcine characteristics in 7 out of 8 genes sequenced. Partial characterization of its remaining VP1, VP2 and VP3 genes along with a porcine rotavirus strain (HP140) uncovered their close genetic relation to porcine strains. VP7 was the only gene segment of this strain with significant genetic identity to human strains. This indicates that a rotavirus reassortant strain with most of its genetic material derived from a porcine strain may cause symptomatic infection in a human host.
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PMID:Characterization of VP1, VP2 and VP3 gene segments of a human rotavirus closely related to porcine strains. 1673 76

Development of a safe, cheap and efficient vaccine against rotavirus is important to reduce the morbidity and mortality associated with gastroenteritis in infants worldwide. High quantities of two inner core rotavirus-derived proteins (VP2 and a nonglycosylated mutant VP6 (VP6(NG)) from the RF81 bovine strain) were produced in the milk of transgenic rabbits. We show here that rectal administration of partially purified milk-derived VP2 and VP6(NG) proteins with the detoxified LT(R192G) adjuvant almost completely prevented fecal shedding induced by a highly infectious challenge in mice with the murine ECw strain. The vaccine generated rotavirus-specific fecal secretory IgA, systemic IgG and IgA and a rotavirus-specific Th1 response. We thus demonstrate in clinically feasible settings that mass production of viral protein in transgenic milk is a promising way to generate subunit vaccine against rotavirus.
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PMID:Recombinant rotavirus inner core proteins produced in the milk of transgenic rabbits confer a high level of protection after intrarectal delivery. 1762 66

Group C rotavirus (GpC RV) is a causative agent of acute gastroenteritis in children and adults. We expressed the three major capsid proteins VP2, VP6 and VP7 of human GpC RV in baculovirus and demonstrated the self-assembly of VP2/6/7 or VP6/7 virus-like particles (VLPs) in insect cells. We examined a number of parameters, including the kinetics of protein synthesis in different cell lines and media, to optimize the most favorable conditions for the synthesis of recombinant viral proteins and the production of VLPs in Sf9 cells. Hyperimmune serum to VP2/6/7 and VP6/7 VLPs recognized individual recombinant proteins of human GpC RV by Western blot analysis. This serum also showed specific reactivities with the corresponding GpC VLPs but not GpA RV by using immune electron microscopy (IEM) and enzyme immunoassay (EIA). The ability to produce an unlimited amount of GpC RV antigen and the availability of high quality antibody will allow us to develop sensitive and specific diagnostic assays to better determine the epidemiology and disease burden of GpC RV in humans.
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PMID:Expression and characterization of human group C rotavirus virus-like particles in insect cells. 1928 29

Rotaviruses (RVs) are nonenveloped, 11-segmented, double-stranded RNA viruses that are major pathogens associated with acute gastroenteritis. Group A, B, and C RVs have been isolated from humans; however, intergroup gene reassortment does not occur for reasons that remain unclear. This restriction might reflect the failure of the viral RNA-dependent RNA polymerase (RdRp; VP1) to recognize and replicate the RNA of a different group. To address this possibility, we contrasted the sequences, structures, and functions of RdRps belonging to RV groups A, B, and C (A-VP1, B-VP1, and C-VP1, respectively). We found that conserved amino acid residues are located within the hollow center of VP1 near the active site, whereas variable, group-specific residues are mostly surface exposed. By creating a three-dimensional homology model of C-VP1 with the A-VP1 crystallographic data, we provide evidence that these RV RdRps are nearly identical in their tertiary folds and that they have the same RNA template recognition mechanism that differs from that of B-VP1. Consistent with the structural data, recombinant A-VP1 and C-VP1 are capable of replicating one another's RNA templates in vitro. Nonetheless, the activity of both RdRps is strictly dependent upon the presence of cognate RV core shell protein A-VP2 or C-VP2, respectively. Together, the results of this study provide unprecedented insight into the structure and function of RV RdRps and support the notion that VP1 interactions may influence the emergence of reassortant viral strains.
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PMID:Shared and group-specific features of the rotavirus RNA polymerase reveal potential determinants of gene reassortment restriction. 1935 62

Human group A rotavirus (GAR) G12 strains are regarded as potentially important pathogens for acute gastroenteritis. On the other hand, to date, the only report of detection of G12 in animals was that of a porcine G12P[7] strain RU172. Strain RU172 formed a separate G12 lineage, distinct from human G12 strains, and by analyses of deduced amino acid sequences, had a VP4, VP6, NSP4-5 of porcine origin. In the present study, we determined the full-length nucleotide sequences of VP1, VP3, and NSP1-3 genes and nearly full-length nucleotide sequence of VP2 gene of RU172. By nucleotide sequence identities and phylogenetic analyses, the VP7-VP4-VP6-VP1-VP2-VP3-NSP1-NSP2-NSP3-NSP4-NSP5 genes of RU172 were assigned to G12-P[7]-I5-R1-C1-M1-A1-N1-T1-E1-H1 genotypes, respectively. Within their respective genotypes, (i) VP1 gene of RU172 exhibited higher genetic relatedness to Wa-like human G12 GARs than porcine strains, (ii) VP2-3 and NSP2 genes clustered separately from the Wa-like human (including G12) and porcine clusters, while (iii) the VP6, NSP1 and NSP3-5 genes clustered with porcine and porcine-like human strains. These observations suggested that (i) the porcine G12 strain might have originated from porcine-human reassortment events, or alternatively, (ii) the Wa-like human and porcine G12 strains might have originated from a common ancestor, and eventually evolved (by genetic drift and shift) with time. Our findings provided important insights into the possible patterns of evolution of the porcine G12 strain.
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PMID:Full genomic analysis and possible origin of a porcine G12 rotavirus strain RU172. 2015 71

Human bocavirus (hBoV) was first discovered in respiratory samples from children in 2005, and has been classified in the Parvoviridae family. hBoV has also been detected in children with acute gastroenteritis. This study was performed to analyze the frequency and phylogeny of hBoV in the respiratory and stool samples of children with acute respiratory tract illnesses and gastroenteritis during the time period beginning 2006 and ending 2008, at the Virology Research Centre, Masih Daneshvari Hospital, NRITLD, Tehran, Iran. Respiratory and stool samples were screened for hBoV by nested polymerase chain reaction with primers from the NS-1 gene. Nine out of 133 respiratory samples (6.8%) and 6 out of 47 stool samples (12.8%) were positive for hBoV. Ten positive samples (7 respiratory and 3 stool samples) were subjected to phylogenetic analysis by sequencing a fragment of the VP1/VP2 gene junction. The results showed a high similarity among isolates (>or=99%). It was found that hBoV isolates can be divided into 3 genetic groups.
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PMID:Phylogenetic analysis of human bocavirus isolated from children with acute respiratory illnesses and gastroenteritis in Iran. 2016 63

Unlike the original canine parvovirus type 2 (CPV-2), CPV-2 variants have gained the ability to replicate in vivo in cats but there is limited information on the disease patterns induced by these variants in the feline host. During 2008, two distinct cases of parvoviral infection were diagnosed in our laboratories. A CPV-2a variant was identified in a 3-month-old Persian kitten displaying clinical sign of feline panleukopenia (FPL) (acute gastroenteritis and marked leukopenia) and oral ulcerations, that died eight days after the onset of the disease. Two pups living in the same pet shop as the cat were found to shed a CPV-2a strain genetically identical to the feline virus and were likely the source of infection. Also, non-fatal infection by a CPV-2c strain occurred in a 2.5-month-old European shorthair kitten displaying non-haemorrhagic diarrhoea and normal white blood cell counts. By sequence analysis of the major capsid protein (VP2) gene, the feline CPV-2c strain showed 100% identity to a recent canine type-2c isolate. Both kittens had been administered multivalent vaccines against common feline pathogens including FPL virus. Whether and to which extent the FPL vaccines can protect cats adequately from the antigenic variants of CPV-2 should be assessed.
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PMID:Characterisation of canine parvovirus strains isolated from cats with feline panleukopenia. 2033 85


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