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1.
J Formos Med Assoc ; 120(1 Pt 1): 212-216, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32448707

RESUMO

BACKGROUND/PURPOSE: The FUT2 gene is a histo-blood group antigen (HBGA) that determines the susceptibility to Norovirus (NoV) infection. This study investigated the clinical significance of the FUT2 gene profile and HBGA expression in NoV infection. METHODS: Fecal specimens were collected from children in Chang-Gung Children's Hospital with acute gastroenteritis (AGE). The medical records were reviewed for clinical data. The viral etiology of gastroenteritis was validated using molecular methods. Genomic DNA was isolated from saliva or whole blood with the Puregene B Kit, according to the manufacturers' instructions. Single-nucleotide polymorphisms (SNPs) were determined by real-time PCR assays. RESULTS: FUT2 gene DNA was examined in 98 children with AGE. NoV was detected by RT-PCR in 44 patients (44.8%), while 54 (55.2%) had non-NoV AGE. Of the 44 NoV patients, 38 (86.3%) were secretors (no G428A mutation) and six (13.7%) were non-secretors (G428A mutation). Of the 54 non-NoV AGE patients, 28 (51.9%) were secretors and 20 (48.1%) were non-secretors. NoV-infected patients who were secretors had more frequent vomiting (P < 0.001), longer duration of diarrhea (P < 0.001), and greater overall disease severity score (P < 0.001) compared with non-secretors. Non-NoV infection secretor AGE patients had a longer duration of diarrhea (P < 0.001) than non-secretors. CONCLUSION: FUT2 secretor status affects NoV AGE in children. Secretor patients have prolonged diarrhea, more frequent vomiting, more severe disease, and greater infection transmissibility than non-secretors.


Assuntos
Gastroenterite , Doença Aguda , Criança , Fucosiltransferases , Gastroenterite/genética , Genótipo , Humanos , Norovirus/genética , Taiwan
2.
Sci Rep ; 10(1): 3686, 2020 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-32111893

RESUMO

Campylobacter is the major bacterial agent of human gastroenteritis worldwide and represents a crucial global public health burden. Species differentiation of C. jejuni and C. coli and phylogenetic analysis is challenged by inter-species horizontal gene transfer. Routine real-time PCR on more than 4000 C. jejuni and C. coli field strains identified isolates with ambiguous PCR results for species differentiation, in particular, from the isolation source eggs. K-mer analysis of whole genome sequencing data indicated the presence of C. coli hybrid strains with huge amounts of C. jejuni introgression. Recombination events were distributed over the whole chromosome. MLST typing was impaired, since C. jejuni sequences were also found in six of the seven housekeeping genes. cgMLST suggested that the strains were phylogenetically unrelated. Intriguingly, the strains shared a stress response set of C. jejuni variant genes, with proposed roles in oxidative, osmotic and general stress defence, chromosome maintenance and repair, membrane transport, cell wall and capsular biosynthesis and chemotaxis. The results have practical impact on routine typing and on the understanding of the functional adaption to harsh environments, enabling successful spreading and persistence of Campylobacter.


Assuntos
Infecções por Campylobacter/genética , Campylobacter coli/genética , Campylobacter jejuni/crescimento & desenvolvimento , Gastroenterite/genética , Variação Genética , Genoma Bacteriano , Recombinação Genética , Animais , Infecções por Campylobacter/diagnóstico , Infecções por Campylobacter/microbiologia , Campylobacter coli/patogenicidade , Campylobacter jejuni/patogenicidade , Gastroenterite/diagnóstico , Gastroenterite/microbiologia , Humanos , Sequenciamento Completo do Genoma
3.
Sensors (Basel) ; 20(3)2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-32028629

RESUMO

Since the norovirus is the main cause of acute gastroenteritis all over the world, its fast detection is crucial in medical diagnostics. In this work, a rapid, sensitive, and selective optical fiber biosensor for the detection of norovirus virus-like particles (VLPs) is reported. The sensor is based on highly sensitive long-period fiber gratings (LPFGs) coated with antibodies against the main coat protein of the norovirus. Several modification methods were verified to obtain reliable immobilization of protein receptors on the LPFG surface. We were able to detect 1 ng/mL norovirus VLPs in a 40-min assay in a label-free manner. Thanks to the application of an optical fiber as the sensor, there is a possibility to increase the user's safety by separating the measurement point from the signal processing setup. Moreover, our sensor is small and light, and the proposed assay is straightforward. The designed LPFG-based biosensor could be applied in both fast norovirus detection and in vaccine testing.


Assuntos
Anticorpos/isolamento & purificação , Técnicas Biossensoriais , Gastroenterite/genética , Norovirus/isolamento & purificação , Gastroenterite/diagnóstico , Gastroenterite/imunologia , Gastroenterite/virologia , Humanos , Norovirus/patogenicidade , Proteínas Virais/imunologia , Proteínas Virais/isolamento & purificação
4.
Biomed Res Int ; 2020: 4707538, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32104692

RESUMO

Norovirus is the leading cause of food-borne disease outbreaks. We conducted this study to examine the incidence and molecular characteristics of norovirus genogroup I infections from acute gastroenteritis outbreaks in Taiwan. Between January 2015 and June 2019, 2121 acute gastroenteritis clusters were reported to Taiwan CDC, of which 351 (16.5%) clusters were positive for NoV GI, and GI.3 was the most prevalent (36.8%) during the study period. The GI.3 infections were significantly higher than non-GI.3 infections in the age groups of 0-5 and 6-18 years. The phylogenetic analysis of the MCC tree revealed that VP1 genes were divided into 3 groups: the GI.P3-GI.3 strains in Taiwan were genetically close to Japan and the GI.Pd-GI.3 strains were segregated into 2 other groups which were genetically closely related to China. In addition, 7 GI.Pd-GI.3 recombinants were identified circulating in Taiwan between 2018 and 2019, and the prevalence of GI.Pd-GI.3 should be monitored to assess whether this could become the new predominant strains in neighboring Asian countries or other parts of the world. Both GI.P3-GI.3 and GI.Pd-GI.3 strains cocirculate, the recombination among these two lineages occurs frequently, contributing to the genetic diversity and multiple occurrences of different norovirus lineages, and their rapid evolution makes future control more difficult. Continued surveillance and timely interventions are critical to understand the complexity of norovirus gene variation and to monitor the new emerging norovirus strains.


Assuntos
Infecções por Caliciviridae , Gastroenterite , Norovirus/genética , Filogenia , Doença Aguda , Adolescente , Adulto , Idoso , Infecções por Caliciviridae/epidemiologia , Infecções por Caliciviridae/genética , Criança , Pré-Escolar , Feminino , Gastroenterite/epidemiologia , Gastroenterite/genética , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Epidemiologia Molecular , Taiwan
5.
Virus Genes ; 56(2): 174-181, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31912284

RESUMO

Genogroup II, genotype 4 noroviruses (GII.4 NoVs) are a leading cause of epidemic and sporadic acute non-bacterial gastroenteritis worldwide. In this study, we isolated a GII.4 NoV strain (designated 2015HN08) from a kid presenting with acute gastroenteritis and determined its near-complete genome sequence. We then performed sequence analysis by comparing this strain with the prototypical GII.4 strain. Virus-like particles (VLPs) derived from the major capsid protein (VP1) were expressed by using a recombinant-baculovirus expression system, and monoclonal antibodies (mAbs) were produced to compare changes in antigenic or histo-blood group antigens (HBGAs) binding sites with the previously characterized GII.4 NoV strain (JZ403). The genome of 2015HN08 was 7559 nucleotides (nt) long, excluding the poly(A) tail. Genotyping analysis indicated that this strain was a Sydney 2012 variant. In comparison with the prototype Sydney 2012 strain, there were 74, 35, and 16 differences in nucleotide sequences in ORF1, OFR2, and OFR3, causing 7, 10, and 6 amino acid (aa) changes, respectively. Expression of VP1 led to successful assembly of VLPs, as demonstrated by electron microscopy. Screening of hybridoma cell supernatants with an in vitro VLP-HBGAs binding blockade assay led to the identification of a cell clone 3G10 that exhibited HBGA-blocking effects. This mAb also exhibited blocking effects against JZ403 strain, suggesting maintenance of the antigenic site and/or HBGAs binding sites between the two strains. In summary, we determined the near-complete genome sequence of a GII.4 Sydney 2012 variant and produced an mAb with blocking effects that might be useful in evaluating the evolution of current Sydney 2012 NoV strains.


Assuntos
Infecções por Caliciviridae/genética , Proteínas do Capsídeo/genética , Gastroenterite/genética , Norovirus/genética , Sítios de Ligação , Infecções por Caliciviridae/epidemiologia , Infecções por Caliciviridae/virologia , Gastroenterite/epidemiologia , Gastroenterite/virologia , Genoma Viral/genética , Genômica , Genótipo , Humanos , Norovirus/patogenicidade , Pandemias , Ligação Proteica
6.
In Vitro Cell Dev Biol Anim ; 55(10): 830-837, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31520371

RESUMO

Intestinal porcine epithelial cells were used for an in vitro analysis of mRNA expression levels of inflammatory cytokines (IL-8, IL-18) and transcriptional factors (MyD88 and NF-κß). Cells were exposed to inorganic and organic zinc sources (in two different concentrations-50 µmol/L and 100 µmol/L) alone or combined with Lactobacillus reuteri B6/1, which was also applied individually. The total exposure time was 4 h. Quantitative reverse transcriptase PCR was used to determine expression levels of the aforementioned parameters. In general, upregulation was observed; however, a decrease of some mRNA's abundance was also determined. Differences in expression were analysed statistically using ANOVA and Tukey analyses. High relative expression was shown for IL-8, IL-18 and MyD88 in groups treated with 100 µmol/L of inorganic sources of zinc (ZnSO4) (p < 0.05), while groups treated with the organic form did not exhibit significant changes in expression. Also, 50 µmol/L of either zinc source did not significantly modify the transcriptional profile of the cytokines and transcription factors, showing that even inorganic sources, at lower concentrations, do not elicit a significant inflammatory reaction. In summary, supplementation of organic zinc source (Gly-Zn chelate) ensures that IL-8, IL-18, MyD88 and NF-κß expression levels are not positively regulated. In contrast, inorganic sources of zinc (ZnSO4) could induce an inflammatory reaction. However, this response could be dampened if L. reuteri B6/1 is administered, showing the helpful aspect of using probiotics to modulate an inflammatory response. Conclusively, the use Gly-Zn chelate appears as an optimal alternative for Zn administration that does not compromise normal intestinal homeostasis.


Assuntos
Citocinas/genética , Células Epiteliais/metabolismo , Probióticos/farmacologia , Zinco/farmacologia , Animais , Células Cultivadas , Células Epiteliais/citologia , Células Epiteliais/efeitos dos fármacos , Gastroenterite/genética , Gastroenterite/patologia , Regulação da Expressão Gênica/efeitos dos fármacos , Intestinos/citologia , Lactobacillus reuteri , Fator 88 de Diferenciação Mieloide/genética , NF-kappa B/genética , Suínos
7.
Epidemiol Infect ; 147: e218, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-31364546

RESUMO

Childhood morbidity and mortality of diarrhoeal diseases are high, particularly in low-income countries and noroviruses and sapoviruses are among the most frequent causes worldwide. Their epidemiology and diversity remain not well studied in many African countries. To assess the positivity rate and the diversity of sapoviruses and noroviruses in Northwest Ethiopia, during November 2015 and April 2016, a total of 450 faecal samples were collected from outpatient children aged <5 years who presented with diarrhoea. Samples were screened for noroviruses and sapoviruses by real-time RT-PCR. Partial VP1 genes were sequenced, genotyped and phylogenetically analysed. Norovirus and sapovirus stool positivity rate was 13.3% and 10.0%, respectively. Noroviruses included GII.4 (35%), GII.6 (20%), GII.17 (13.3%), GII.10 (10%), GII.2 (6.7%), GII.16 (5%), GII.7 (3.3%), GII.9, GII.13, GII.20 and GI.3 (1.7% each) strains. For sapoviruses, GI.1, GII.1 (20.0% each), GII.6 (13.3%), GI.2 (8.9%), GII.2 (11.1%), GV.1 (8.9%), GIV.1 (6.7%), GI.3 and GII.4 (2.2% each) genotypes were detected. This study demonstrates a high genetic diversity of noroviruses and sapoviruses in Northwest Ethiopia. The positivity rate in stool samples from young children with diarrhoea was high for both caliciviruses. Continued monitoring is recommended to identify trends in genetic diversity and seasonal variations.


Assuntos
Proteínas de Bactérias/genética , Infecções por Caliciviridae/epidemiologia , Gastroenterite/epidemiologia , Norovirus/genética , Sapovirus/genética , Infecções por Caliciviridae/genética , Criança , Pré-Escolar , Estudos de Coortes , Países em Desenvolvimento , Etiópia/epidemiologia , Fezes/virologia , Feminino , Gastroenterite/genética , Gastroenterite/microbiologia , Variação Genética , Genótipo , Humanos , Incidência , Lactente , Masculino , Norovirus/isolamento & purificação , Pacientes Ambulatoriais/estatística & dados numéricos , Filogenia , Saúde Pública , Estudos Retrospectivos , Medição de Risco , Sapovirus/isolamento & purificação , Estações do Ano , Análise de Sobrevida
8.
PLoS Genet ; 15(6): e1008233, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31233504

RESUMO

Pathogenic Salmonella strains that cause gastroenteritis are able to colonize and replicate within the intestines of multiple host species. In general, these strains have retained an ability to form the rdar morphotype, a resistant biofilm physiology hypothesized to be important for Salmonella transmission. In contrast, Salmonella strains that are host-adapted or even host-restricted like Salmonella enterica serovar Typhi, tend to cause systemic infections and have lost the ability to form the rdar morphotype. Here, we investigated the rdar morphotype and CsgD-regulated biofilm formation in two non-typhoidal Salmonella (NTS) strains that caused invasive disease in Malawian children, S. Typhimurium D23580 and S. Enteritidis D7795, and compared them to a panel of NTS strains associated with gastroenteritis, as well as S. Typhi strains. Sequence comparisons combined with luciferase reporter technology identified key SNPs in the promoter region of csgD that either shut off biofilm formation completely (D7795) or reduced transcription of this key biofilm regulator (D23580). Phylogenetic analysis showed that these SNPs are conserved throughout the African clades of invasive isolates, dating as far back as 80 years ago. S. Typhi isolates were negative for the rdar morphotype due to truncation of eight amino acids from the C-terminus of CsgD. We present new evidence in support of parallel evolution between lineages of nontyphoidal Salmonella associated with invasive disease in Africa and the archetypal host-restricted invasive serovar; S. Typhi. We hypothesize that the African invasive isolates are becoming human-adapted and 'niche specialized' with less reliance on environmental survival, as compared to gastroenteritis-causing isolates.


Assuntos
Evolução Biológica , Gastroenterite/genética , Infecções por Salmonella/genética , Salmonella typhimurium/genética , África/epidemiologia , Biofilmes/crescimento & desenvolvimento , Criança , Gastroenterite/epidemiologia , Gastroenterite/microbiologia , Humanos , Filogenia , Polimorfismo de Nucleotídeo Único/genética , Infecções por Salmonella/microbiologia , Infecções por Salmonella/transmissão , Salmonella typhimurium/patogenicidade , Transativadores/genética
9.
Viruses ; 11(4)2019 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-30974776

RESUMO

Group A rotaviruses are a major cause of acute gastroenteritis in children. The diversity and unequal geographical prevalence of rotavirus genotypes have been linked to histo-blood group antigens (HBGAs) in different human populations. In order to evaluate the role of HBGAs in rotavirus infections in our population, secretor status (FUT2+), ABO blood group, and Lewis antigens were determined in children attended for rotavirus gastroenteritis in Valencia, Spain. During three consecutive years (2013-2015), stool and saliva samples were collected from 133 children with rotavirus infection. Infecting viral genotypes and HBGAs were determined in patients and compared to a control group and data from blood donors. Rotavirus G9P[8] was the most prevalent strain (49.6%), followed by G1P[8] (20.3%) and G12P[8] (14.3%). Rotavirus infected predominantly secretor (99%) and Lewis b positive (91.7%) children. Children with blood group A and AB were significantly more prone to rotavirus gastroenteritis than those with blood group O. Our results confirm that a HBGA genetic background is linked to rotavirus P[8] susceptibility. Rotavirus P[8] symptomatic infection is manifestly more frequent in secretor-positive (FUT2+) than in non-secretor individuals, although no differences between rotavirus G genotypes were found.


Assuntos
Antígenos de Grupos Sanguíneos/análise , Predisposição Genética para Doença , Infecções por Rotavirus/genética , Criança , Pré-Escolar , Fezes/virologia , Feminino , Gastroenterite/genética , Gastroenterite/patologia , Genótipo , Humanos , Lactente , Recém-Nascido , Masculino , Rotavirus/classificação , Rotavirus/genética , Rotavirus/isolamento & purificação , Infecções por Rotavirus/patologia , Saliva/virologia , Espanha
10.
Sci Rep ; 9(1): 3286, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30824842

RESUMO

Viral gastroenteritis causes high morbidity worldwide. In this study, stool samples from 179 children aged 0-6 years attending Danish day care centers were investigated for gastrointestinal viruses. Each child was observed for one year with submission of samples and questionnaires every two months. Adenovirus, norovirus, rotavirus, and sapovirus were detected in samples using real-time PCR. A total of 229 (33%) of the 688 samples collected tested positive for at least one virus. At the first sampling point, adenovirus was shed by 6%, norovirus genotype I by 3% and genotype II by 12%, rotavirus A by 9%, and sapovirus by 21% of the 142 children included in the risk factor analyses. Increasing age was identified as a protective factor against testing positive for gastrointestinal virus, whereas nausea during the previous two months was positively associated with testing positive. Odds of shedding adenovirus were 9.6 times higher among children treated with antibiotics within the previous two months than among children who were not. Gastrointestinal viruses were shed year-round and high viral loads were observed in samples from both symptomatic and asymptomatic children, suggesting children in day care as a reservoir and a possible source of spreading of viruses into the community.


Assuntos
Infecções por Adenovirus Humanos , Adenovírus Humanos/genética , Creches , Gastroenterite , Infecções por Vírus de RNA , Vírus de RNA/genética , Infecções por Adenovirus Humanos/epidemiologia , Infecções por Adenovirus Humanos/genética , Infecções por Adenovirus Humanos/virologia , Criança , Pré-Escolar , Estudos Transversais , Dinamarca/epidemiologia , Feminino , Seguimentos , Gastroenterite/epidemiologia , Gastroenterite/genética , Gastroenterite/virologia , Humanos , Lactente , Masculino , Infecções por Vírus de RNA/epidemiologia , Infecções por Vírus de RNA/genética , Infecções por Vírus de RNA/virologia
11.
Virus Genes ; 55(3): 280-289, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30725444

RESUMO

Noroviruses are leading cause of acute gastroenteritis worldwide. In our previous study, we established an in vitro histo-blood group antigens (HBGAs) binding blockade assay against GII.3 Norovirus virus like particles (VLPs) with trypsin digestion. In this study, we characterized the blocking antibody binding site and epitope type (linear or conformational) by using hyperimmune sera produced against different antigens. VP1 from Jingzhou402 (GII.3, JZ402) strain was expressed by using pGEX-6p-1 expression vector and the insoluble proteins were purified for immunization in rabbit. Previously characterized chimeric VP1-assembled VLPs (GII.4-VP1/GII.3-P2) were used to immunize guinea pig. Peptides reactive with hyperimmune serum against VLPs derived from the VP1 of JZ402 strain were conjugated with BSA and used to immunize rabbits. Hyperimmune sera against above antigens and JZ402 and JZ403 strain-derived VLPs were used to compare their HBGAs blocking effects. Rabbit anti-GST-VP1 and BSA-peptide conjugated hyperimmune sera demonstrated no blocking effects against the binding of GII.3 and GII.4 NoV VLPs to salivary HBGAs. Guinea pig anti-GII.4-VP1/GII.3-P2 hyperimmune serum blocked the binding of trypsin cleaved GII.3 VLPs to salivary HBGAs with no or very weak blocking effects against the binding of GII.4 VLPs to salivary HBGAs. Our data indicated that HBGAs blocking antibodies primarily bound the P2 domain of GII.3 NoV VP1 and their binding epitopes were most probably conformation-dependent.


Assuntos
Antígenos de Grupos Sanguíneos/genética , Epitopos/genética , Gastroenterite/genética , Norovirus/genética , Animais , Anticorpos/genética , Anticorpos/imunologia , Sítios de Ligação/imunologia , Antígenos de Grupos Sanguíneos/imunologia , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/imunologia , Epitopos/imunologia , Gastroenterite/imunologia , Gastroenterite/virologia , Genótipo , Cobaias , Humanos , Norovirus/imunologia , Ligação Proteica , Coelhos , Transdução de Sinais/genética
12.
Mol Nutr Food Res ; 63(8): e1800720, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30656830

RESUMO

SCOPE: Intestinal dysfunction consists of a defective barrier function, which allows the influx of luminal endotoxins, thus causing intestinal inflammation. Proanthocyanidins are natural bioactive compounds that could modulate intestinal dysfunction. This study analyzes the protective effects of proanthocyanidins in a rat model of intestinal dysfunction. METHODS AND RESULTS: To investigate the preventive effects of both high dietary (75 mg kg-1 body weight) and pharmacological (375 mg kg-1 body weight) oral doses of proanthocyanidins (GSPE), rat intestinal dysfunction is induced with LPS (i.p.). In vivo intestinal permeability (ovalbumin [OVA] assay) and systemic inflammation and endotoxemia (TNF-α and LPS plasma levels) are assessed. Intestinal inflammation and oxidative stress are determined using myeloperoxidase (MPO), cyclooxygenase-2 (COX-2) activities, and reactive oxygen species (ROS) levels, respectively. Ileal gene expression of permeability/inflammatory genes is analyzed. LPS administration induces intestinal permeability, inflammation, and oxidative stress. GSPE normalizes in vivo OVA levels. In the small intestine, the GSPE treatment decreases MPO and COX-2 activities; modulates the ileum inflammatory and permeability proteins gene expression; and in the large intestine, prevents increase of ROS levels. CONCLUSIONS: Proanthocyanidins, at nutritional and pharmacological doses, prevents endotoxin-induced-intestinal inflammation, permeability, and oxidative stress in rats differentially in each intestinal section. Proanthocyanidins are nutritional-therapeutic novel candidates for preventing intestinal dysfunction.


Assuntos
Gastroenterite/prevenção & controle , Extrato de Sementes de Uva/farmacologia , Intestinos/efeitos dos fármacos , Proantocianidinas/farmacologia , Administração Oral , Animais , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Modelos Animais de Doenças , Gastroenterite/induzido quimicamente , Gastroenterite/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Extrato de Sementes de Uva/administração & dosagem , Lipopolissacarídeos/toxicidade , Masculino , Ovalbumina/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Permeabilidade , Proantocianidinas/administração & dosagem , Substâncias Protetoras/farmacologia , Ratos Wistar
13.
Microb Genom ; 4(10)2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30248001

RESUMO

Novel adenovirus genotypes are associated with outbreaks of disease, such as acute gastroenteritis, renal disease, upper respiratory tract infection and keratoconjunctivitis. Here, we identify novel and variant adenovirus genotypes in children coinfected with enterotoxigenic Escherichia coli, in Bangladesh. Metagenomic sequencing of stool was performed and whole adenovirus genomes were extracted. A novel species D virus, designated genotype 90 (P33H27F67) was identified, and the partial genome of a putative recombinant species B virus was recovered. Furthermore, the enteric types HAdV-A61 and HAdV-A40 were found in stool specimens. Knowledge of the diversity of adenovirus genomes circulating worldwide, especially in low-income countries where the burden of disease is high, will be required to ensure that future vaccination strategies cover the diversity of adenovirus strains associated with disease.


Assuntos
Infecções por Adenovirus Humanos/genética , Adenovírus Humanos/genética , Gastroenterite/virologia , Genoma Viral , Genótipo , Ceratoconjuntivite/virologia , Infecções por Adenovirus Humanos/epidemiologia , Infecções por Adenovirus Humanos/prevenção & controle , Adenovírus Humanos/isolamento & purificação , Bangladesh/epidemiologia , Criança , Pré-Escolar , Fezes/virologia , Feminino , Gastroenterite/epidemiologia , Gastroenterite/genética , Gastroenterite/prevenção & controle , Humanos , Ceratoconjuntivite/epidemiologia , Ceratoconjuntivite/genética , Ceratoconjuntivite/prevenção & controle , Masculino
14.
Arch Virol ; 163(12): 3265-3273, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30143876

RESUMO

GII.3 and GII.6 noroviruses (NoVs) are similar in several aspects, including the presence of a short sequence insertion in the P2 domain of the major capsid protein (VP1) and trypsin susceptibility of VP1-containing virus-like particles (VLPs). In this study, we generated two constructs with the S or P domains of VP1 from GII.3 and GII.6 NoV strains exchanged (GII.3S/GII.6P and GII.6S/GII.3P), and the resultant chimeric capsid proteins were expressed from recombinant baculoviruses. The assembly of VLPs was confirmed by electron microscopy, and the susceptibility of assembled VLPs to trypsin digestion was analyzed by SDS-PAGE. Salivary histo-blood group antigen (HBGA) binding and binding blockade assays were performed to determine the binding characteristics of chimeric VP1-containing VLPs with and without trypsin digestion. Our results indicated that both expressed GII.3S/GII.6P and GII.6S/GII.3P chimeric proteins successfully assembled into VLPs. Trypsin digestion of VLPs assembled from both chimeric proteins led to the generation of two fragments with molecular sizes similar to those of wild-type VP1-containing VLPs. An in vitro salivary HBGA binding assay demonstrated that VLPs assembled from both chimeric proteins exhibited enhanced binding after trypsin cleavage. An HBGA binding blockade assay indicated that the binding of GII.3S/GII.6P and GII.6S/GII.3P VLPs against salivary HBGAs could only be blocked by GII.3 and GII.6 NoV VLP-specific hyperimmune sera, respectively. For GII.6 and GII.3S/GII.6P VLPs, a difference in binding enhancement after trypsin cleavage was observed. Our results demonstrate that the S domains of GII.3 and GII.6 NoV VP1 are interchangeable and that the S domain affects the binding of the P domain to HBGAs.


Assuntos
Antígenos de Grupos Sanguíneos/metabolismo , Infecções por Caliciviridae/metabolismo , Infecções por Caliciviridae/virologia , Proteínas do Capsídeo/metabolismo , Norovirus/metabolismo , Infecções por Caliciviridae/genética , Capsídeo/química , Capsídeo/metabolismo , Proteínas do Capsídeo/química , Proteínas do Capsídeo/genética , Gastroenterite/genética , Gastroenterite/metabolismo , Gastroenterite/virologia , Genótipo , Humanos , Norovirus/química , Norovirus/genética , Norovirus/ultraestrutura , Ligação Proteica , Domínios Proteicos , Tripsina/química
15.
Sci Rep ; 8(1): 12961, 2018 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-30154494

RESUMO

Human strains of rotavirus A (RVAs) recognize fucosylated glycans belonging to histo-blood group antigens (HBGAs) through their spike protein VP8*. Lack of these ligands due to genetic polymorphisms is associated with resistance to gastroenteritis caused by P[8] genotype RVAs. With the aim to delineate the contribution of HBGAs in the process, we analyzed the glycan specificity of VP8* proteins from various P genotypes. Binding to saliva of VP8* from P[8] and P[4] genotypes required expression of both FUT2 and FUT3 enzymes, whilst binding of VP8* from the P[14] genotype required FUT2 and A enzymes. We further defined a glycan motif, GlcNAcß3Galß4GlcNAc, recognized by P[6] clinical strains. Conversion into Lewis antigens by the FUT3 enzyme impaired recognition, explaining their lower binding to saliva of Lewis positive phenotype. In addition, the presence of neutralizing antibodies was associated with the presence of the FUT2 wild type allele in sera from young healthy adults. Nonetheless, in vitro infection of transformed cell lines was independent of HBGAs expression, indicating that HBGAs are not human RV receptors. The match between results from saliva-based binding assays and the epidemiological data indicates that the polymorphism of human HBGAs controls susceptibility to RVAs, although the exact mechanism remains unclear.


Assuntos
Antígenos de Grupos Sanguíneos , Gastroenterite , Proteínas de Ligação a RNA , Infecções por Rotavirus , Rotavirus , Proteínas não Estruturais Virais , Adolescente , Adulto , Animais , Antígenos de Grupos Sanguíneos/genética , Antígenos de Grupos Sanguíneos/metabolismo , Células CACO-2 , Chlorocebus aethiops , Feminino , Fucosiltransferases/genética , Fucosiltransferases/metabolismo , Gastroenterite/genética , Gastroenterite/metabolismo , Gastroenterite/virologia , Humanos , Masculino , Ligação Proteica , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Rotavirus/genética , Rotavirus/metabolismo , Infecções por Rotavirus/genética , Infecções por Rotavirus/metabolismo , Células Vero , Proteínas não Estruturais Virais/genética , Proteínas não Estruturais Virais/metabolismo
16.
J Infect Dis ; 218(5): 716-725, 2018 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-29912471

RESUMO

Background: Human noroviruses (HuNoVs) are a prominent cause of gastroenteritis, yet fundamental questions remain regarding epidemiology, diversity, and immunity in sub-Saharan African children. We investigated HuNoV seroprevalence and genetic and sociodemographic risk factors in Ugandan children. Methods: We randomly screened 797 participants of a longitudinal birth cohort (Entebbe, EMaBS) and 378 from a cross-sectional survey (rural Lake Victoria, LaVIISWA), for antibodies against HuNoV genotypes by ELISA. We used linear regression modeling to test for associations between HuNoV antibody levels and sociodemographic factors, and with the human susceptibility rs601338 FUT2 secretor SNP and histo-blood group antigens (A/B/O). Results: Of EMaBS participants, 76.6% were seropositive by age 1, rising to 94.5% by age 2 years. Seroprevalence in 1 year olds of the rural LaVIISWA survey was even higher (95%). In the birth cohort, 99% of seropositive 2 year olds had responses to multiple HuNoV genotypes. We identified associations between secretor status and genogroup GII antibody levels (GII.4 P = 3.1 × 10-52), as well as ABO and GI (GI.2 P = 2.1 × 10-12). Conclusions: HuNoVs are highly prevalent in Ugandan children, indicating a substantial burden of diarrhea-associated morbidity with recurrent infections. Public health interventions, including vaccination, and increased surveillance are urgently needed.


Assuntos
Anticorpos Antivirais/sangue , Infecções por Caliciviridae/epidemiologia , Infecções por Caliciviridae/virologia , Variação Genética , Genótipo , Norovirus/classificação , Norovirus/imunologia , Antígenos de Grupos Sanguíneos/análise , Infecções por Caliciviridae/genética , Infecções por Caliciviridae/imunologia , Pré-Escolar , Estudos Transversais , Demografia , Suscetibilidade a Doenças , Ensaio de Imunoadsorção Enzimática , Feminino , Fucosiltransferases/genética , Gastroenterite/epidemiologia , Gastroenterite/genética , Gastroenterite/imunologia , Gastroenterite/virologia , Humanos , Lactente , Recém-Nascido , Estudos Longitudinais , Masculino , Norovirus/genética , Polimorfismo de Nucleotídeo Único , Gravidez , Fatores de Risco , Estudos Soroepidemiológicos , Fatores Socioeconômicos , Uganda/epidemiologia
17.
Medicine (Baltimore) ; 97(23): e11006, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29879060

RESUMO

Conventional methods for identifying gastroenteritis pathogens are time consuming, more likely to result in a false-negative, rely on personnel with diagnostic expertise, and are dependent on the specimen status. Alternatively, molecular diagnostic methods permit the rapid, simultaneous detection of multiple pathogens with high sensitivity and specificity. The present study compared conventional methods with the Luminex xTAG Gastrointestinal Pathogen Panel (xTAG GPP) for the diagnosis of infectious gastroenteritis in northern Taiwan. From July 2015 to April 2016, 217 clinical fecal samples were collected from patients with suspected infectious gastroenteritis. All specimens were tested using conventional diagnostic techniques following physicians' orders as well as with the xTAG GPP. The multiplex polymerase chain reaction (PCR) approach detected significantly more positive samples with bacterial, viral, and/or parasitic infections as compared to conventional analysis (55.8% vs 40.1%, respectively; P < .001). Moreover, multiplex PCR could detect Escherichia coli O157, enterotoxigenic E coli, Shiga-like toxin-producing E coli, Cryptosporidium, and Giardia, which were undetectable by conventional methods. Furthermore, 48 pathogens in 23 patients (10.6%) with coinfections were identified only using the multiplex PCR approach. Of which, 82.6% were from pediatric patients. Because the detection rates using multiplex PCR are higher than conventional methods, and some pediatric pathogens could only be detected by multiplex PCR, this approach may be useful in rapidly diagnosing diarrheal disease in children and facilitating treatment initiation. Further studies are necessary to determine if multiplex PCR improves patient outcomes and reduces costs.


Assuntos
Coinfecção/genética , Diarreia/genética , Gastroenterite/genética , Gastroenteropatias/genética , Reação em Cadeia da Polimerase Multiplex/métodos , Coinfecção/microbiologia , Coinfecção/parasitologia , Coinfecção/virologia , Cryptosporidium/genética , Diarreia/microbiologia , Diarreia/parasitologia , Diarreia/virologia , Escherichia coli/genética , Fezes/microbiologia , Feminino , Gastroenterite/microbiologia , Gastroenterite/parasitologia , Gastroenterite/virologia , Gastroenteropatias/microbiologia , Gastroenteropatias/parasitologia , Gastroenteropatias/virologia , Giardia/genética , Humanos , Masculino , Técnicas de Diagnóstico Molecular/métodos , Sensibilidade e Especificidade , Taiwan/epidemiologia
18.
J Pept Sci ; 24(3)2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29542263

RESUMO

The human gut barrier is the tissue exposed to the highest load of microorganisms, harbouring 100 trillion bacteria. In addition, the gut's renewal rate outruns that of any other human tissue. Antimicrobial peptides (AMPs) are highly optimized defense molecules in the intestinal barrier optimized to maintain gastrointestinal homeostasis. Alterations in AMPs activity can lead to or result from human gastrointestinal diseases. In this review, unique, conserved, or otherwise regular alterations in the expression patterns of human AMPs across gastrointestinal inflammatory and infectious diseases were analyzed for pattern elucidation. Human gastrointestinal diseases are associated with alterations in gut AMPs' expression patterns in a peptide-specific, disease-specific, and pathogen-specific way, modulating human gastrointestinal functioning. Across diseases, there is a (i) marked reduction in otherwise constitutively expressed AMPs, leading to increased disease susceptibility, and a (ii) significant increase in the expression of inducible AMPs, leading to tissue damage and disease severity. Infections and inflammatory conditions are associated with altered gene expression in the gut, whose patterns may favour cellular metaplasia, mucosal dysfunction, and disease states. Altered expression of AMPs can thus thrive disease severity and evolution since its early stages. Nevertheless, the modulation of AMP expression patterns unveils promising therapeutic targets.


Assuntos
Peptídeos Catiônicos Antimicrobianos/genética , Gastroenteropatias/metabolismo , Trato Gastrointestinal/metabolismo , Peptídeos Catiônicos Antimicrobianos/metabolismo , Doenças Transmissíveis/genética , Doenças Transmissíveis/metabolismo , Gastroenterite/genética , Gastroenterite/metabolismo , Gastroenteropatias/genética , Neoplasias Gastrointestinais/genética , Neoplasias Gastrointestinais/metabolismo , Regulação da Expressão Gênica , Predisposição Genética para Doença , Humanos
19.
Gigascience ; 7(3): 1-13, 2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29385462

RESUMO

Background: Giardia is a protozoan parasite of public health relevance that causes gastroenteritis in a wide range of hosts. Two genetically distinct lineages (assemblages A and B) are responsible for the human disease. Although it is clear that differences in virulence occur, the pathogenesis and virulence of Giardia remain poorly understood. Results: The genome of Giardia is believed to contain open reading frames that could encode as many as 6000 proteins. By successfully applying quantitative proteomic analyses to the whole parasite and to the supernatants derived from parasite culture of assemblages A and B, we confirm expression of ∼1600 proteins from each assemblage, the vast majority of which are common to both lineages. To look for signature enrichment of secreted proteins, we considered the ratio of proteins in the supernatant compared with the pellet, which defined a small group of enriched proteins, putatively secreted at a steady state by cultured growing trophozoites of both assemblages. This secretome is enriched with proteins annotated to have N-terminal signal peptide. The most abundant secreted proteins include known virulence factors such as cathepsin B cysteine proteases and members of a Giardia superfamily of cysteine-rich proteins that comprise variant surface proteins, high-cysteine membrane proteins, and a new class of virulence factors, the Giardia tenascins. We demonstrate that physiological function of human enteric epithelial cells is disrupted by such soluble factors even in the absence of the trophozoites. Conclusions: We are able to propose a straightforward model of Giardia pathogenesis incorporating key roles for the major Giardia-derived soluble mediators.


Assuntos
Gastroenterite/genética , Giardia/genética , Giardíase/genética , Tenascina/metabolismo , Animais , Linhagem da Célula/genética , Proteínas da Matriz Extracelular/genética , Gastroenterite/parasitologia , Genoma/genética , Genótipo , Giardia/patogenicidade , Giardíase/parasitologia , Humanos , Proteínas do Tecido Nervoso/genética , Filogenia , Proteômica , Tenascina/genética
20.
PLoS Pathog ; 14(2): e1006858, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29390040

RESUMO

Gastrointestinal infections caused by enteric yersiniae can become persistent and complicated by relapsing enteritis and severe autoimmune disorders. To establish a persistent infection, the bacteria have to cope with hostile surroundings when they transmigrate through the intestinal epithelium and colonize underlying gut-associated lymphatic tissues. How the bacteria gain a foothold in the face of host immune responses is poorly understood. Here, we show that the CNFY toxin, which enhances translocation of the antiphagocytic Yop effectors, induces inflammatory responses. This results in extensive tissue destruction, alteration of the intestinal microbiota and bacterial clearance. Suppression of CNFY function, however, increases interferon-γ-mediated responses, comprising non-inflammatory antimicrobial activities and tolerogenesis. This process is accompanied by a preterm reprogramming of the pathogen's transcriptional response towards persistence, which gives the bacteria a fitness edge against host responses and facilitates establishment of a commensal-type life style.


Assuntos
Toxinas Bacterianas/genética , Deleção de Genes , Inflamação/genética , Fatores de Virulência/genética , Infecções por Yersinia pseudotuberculosis/genética , Yersinia pseudotuberculosis/genética , Animais , Ceco/microbiologia , Progressão da Doença , Feminino , Gastroenterite/genética , Gastroenterite/microbiologia , Gastroenteropatias/genética , Gastroenteropatias/microbiologia , Microbioma Gastrointestinal/fisiologia , Inflamação/microbiologia , Camundongos , Camundongos Endogâmicos BALB C , Organismos Geneticamente Modificados , Yersinia pseudotuberculosis/patogenicidade , Infecções por Yersinia pseudotuberculosis/patologia
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