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1.
BMJ Case Rep ; 14(1)2021 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-33462001

RESUMO

A 75-year-old man was admitted with a 3-month history of worsening diarrhoea and weight loss. He was on long-term immunosuppression following cardiac transplantation. Investigations revealed herpes simplex oesophagitis and stool samples were positive for norovirus. Treatment with acyclovir and nitazoxanide resulted in a complete resolution of symptoms. Norovirus is a common cause of infectious gastroenteritis, but immunosuppressed patients may present with chronic diarrhoea rather than an acute illness. This case highlights the importance of a low clinical threshold for testing for norovirus infection in immunocompromised patients.


Assuntos
Infecções por Caliciviridae/imunologia , Diarreia/virologia , Gastroenterite/imunologia , Hospedeiro Imunocomprometido , Norovirus/isolamento & purificação , Complicações Pós-Operatórias/imunologia , Perda de Peso , Idoso , Infecções por Caliciviridae/complicações , Infecções por Caliciviridae/diagnóstico , Doença Crônica , Diarreia/imunologia , Gastroenterite/complicações , Gastroenterite/diagnóstico , Transplante de Coração , Humanos , Masculino , Complicações Pós-Operatórias/diagnóstico , Perda de Peso/imunologia
2.
Chest ; 157(2): e41-e45, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32033660

RESUMO

CASE PRESENTATION: A 72-year-old man presented to our ED less than 24 hours following the acute onset of nausea, vomiting, and diarrhea. Within 12 hours of symptom onset, he noted bilateral lower extremity pain and swelling. His pain was associated with a new violaceous irregular rash on the anterior aspect of both feet and legs. There was no history of inciting trauma or recent wounds. In addition, there was no history of consumption of raw or undercooked food (including seafood) or recent change in food source. There was accompanying fever and chills for the same duration and painful swelling of his left thumb. His comorbidities included stage IIIb classical Hodgkin lymphoma diagnosed 4 months prior. His last dose of doxorubicin, bleomycin, vinblastine, and dacarbazine chemotherapy was 4 days before presentation. He had previously failed anti-CD30 monoclonal therapy resulting from attributed pancolitis.


Assuntos
Celulite (Flegmão)/diagnóstico , Gastroenterite/diagnóstico , Doença de Hodgkin/imunologia , Hospedeiro Imunocomprometido , Miosite/diagnóstico , Sepse/diagnóstico , Vibrioses/diagnóstico , Idoso , Antibacterianos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Celulite (Flegmão)/imunologia , Celulite (Flegmão)/terapia , Desbridamento , Gastroenterite/imunologia , Gastroenterite/terapia , Doença de Hodgkin/complicações , Doença de Hodgkin/tratamento farmacológico , Humanos , Dermatoses da Perna , Masculino , Miosite/imunologia , Miosite/terapia , Músculo Quadríceps/diagnóstico por imagem , Sepse/imunologia , Sepse/terapia , Infecções dos Tecidos Moles/diagnóstico , Infecções dos Tecidos Moles/imunologia , Infecções dos Tecidos Moles/terapia , Tomografia Computadorizada por Raios X , Vibrioses/imunologia , Vibrioses/terapia , Vibrio vulnificus
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
5.
Transbound Emerg Dis ; 67 Suppl 2: 49-59, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31232527

RESUMO

Neorickettsia helminthoeca (NH), the agent of salmon poisoning disease or canine neorickettiosis (CN), is a bacterial endosymbiont of the nematode Nanophyetus salmincola, and infections are spreading among specific fish-eating mammalians. This article describes the pathologic and immunohistochemical findings associated with spontaneous NH-induced infections in dogs from Southern Brazil. The principal pathologic findings were hypertrophy of Peyer patches and lymphadenopathy with lymphocytic proliferation, chronic interstitial pneumonia, and chronic enteritis associated with positive intralesional immunoreactivity to antigens of NH within macrophages and histiocytes. Positive immunoreactivity against canine parvovirus-2 (CPV-2) or/and canine distemper virus was not detected in the evaluated intestinal segments or in the samples from the cerebellum and lungs, respectively, from the dogs evaluated. These findings demonstrated that NH was involved in the enteric, pulmonary, and lymphoid lesions herein described, and provide additional information to confirm the occurrence of this bacterial endosymbiont within this geographical location. It is proposed that chronic pneumonia should be considered as a pathologic manifestation of NH-induced infections. Additionally, our results show that the occurrences of CN seem to be underdiagnosed in Southern Brazil due to the confusion with the incidence of CPV-2.


Assuntos
Infecções por Anaplasmataceae/veterinária , Doenças do Cão/microbiologia , Gastroenterite/veterinária , Pneumopatias/veterinária , Doenças Linfáticas/veterinária , Neorickettsia/isolamento & purificação , Animais , Anticorpos Antibacterianos/sangue , Anticorpos Antivirais/sangue , Antígenos de Bactérias/imunologia , Brasil/epidemiologia , Reações Cruzadas , Vírus da Cinomose Canina/imunologia , Doenças do Cão/epidemiologia , Doenças do Cão/imunologia , Cães , Feminino , Gastroenterite/epidemiologia , Gastroenterite/imunologia , Gastroenterite/microbiologia , Imuno-Histoquímica , Pneumopatias/epidemiologia , Pneumopatias/imunologia , Pneumopatias/microbiologia , Doenças Linfáticas/epidemiologia , Doenças Linfáticas/imunologia , Doenças Linfáticas/microbiologia , Masculino , Neorickettsia/imunologia , Parvovirus Canino/imunologia , Simbiose
6.
Vaccine ; 37(51): 7509-7518, 2019 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-31585726

RESUMO

Enteric viruses cause diverse infections with substantial morbidity and mortality in children, rotavirus (RV) and norovirus (NoV) being the leading agents of severe pediatric gastroenteritis. Coxsackie B viruses (CVB) are common enteroviruses (EV), associated with increased incidence of severe neonatal CVB disease with potentially fatal consequences. To prevent majority of childhood gastroenteritis, we have developed a non-live NoV-RV combination vaccine consisting of NoV virus-like particles (VLPs) and RV oligomeric rVP6 protein that induced protective immune responses to NoV and RV in mice. Moreover, rVP6 acted as an adjuvant for NoV VLPs. Here, we investigated a possibility to include a third enteric virus-derived antigen in the candidate NoV-RV vaccine, by adding recombinant nanoparticles derived from EV CVB1. To examine immunogenicity of EV-NoV-RV vaccine, BALB/c mice were immunized intramuscularly twice with 10 µg CVB1 VLPs, GII.4 VLPs and rVP6 nanotubes, either separately or combined. To evaluate the adjuvant effect of rVP6 on EV responses, mice received 0.3 µg CVB1 VLPs with or without 10 µg rVP6. Comparable serum IgG antibodies were detected whether the antigens were administered separately or in combination. Each formulation generated IgG1 and IgG2a antibodies, indicating a mixed Th2/Th1-type response. CVB1 VLPs skewed the isotype distribution slightly towards IgG1 subtype, while EV-NoV-RV combination vaccine induced unbiased Th1/Th2 responses to CVB1. Each antigen also induced T cell mediated immunity measured by IFN-γ secretion to specific stimulants ex vivo. Antisera raised by single antigens and combined formulation also exhibited strong neutralizing ability against CVB1 and NoV GII.4. Further, rVP6 showed an adjuvant effect on CVB1 responses, sparing the VLP dose and homogenizing the responses. Finally, the results support inclusion of additional antigens in the candidate NoV-RV combination vaccine to combat severe childhood infections and confirm adjuvant effect of rVP6 nanostructures.


Assuntos
Infecções por Caliciviridae/prevenção & controle , Infecções por Enterovirus/prevenção & controle , Gastroenterite/prevenção & controle , Infecções por Rotavirus/prevenção & controle , Vacinação/métodos , Vacinas de Partículas Semelhantes a Vírus/administração & dosagem , Vacinas Virais/administração & dosagem , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Antígenos Virais/química , Antígenos Virais/imunologia , Infecções por Caliciviridae/imunologia , Infecções por Caliciviridae/virologia , Proteínas do Capsídeo/química , Proteínas do Capsídeo/imunologia , Criança , Enterovirus Humano B/química , Enterovirus Humano B/efeitos dos fármacos , Enterovirus Humano B/imunologia , Infecções por Enterovirus/imunologia , Infecções por Enterovirus/virologia , Feminino , Gastroenterite/imunologia , Gastroenterite/virologia , Humanos , Esquemas de Imunização , Imunogenicidade da Vacina , Imunoglobulina G/sangue , Imunoglobulina G/classificação , Camundongos , Camundongos Endogâmicos BALB C , Norovirus/química , Norovirus/efeitos dos fármacos , Norovirus/imunologia , Rotavirus/química , Rotavirus/efeitos dos fármacos , Rotavirus/imunologia , Infecções por Rotavirus/imunologia , Infecções por Rotavirus/virologia , Vacinas Sintéticas , Vacinas de Partículas Semelhantes a Vírus/biossíntese , Vacinas Virais/biossíntese , Vírion/química , Vírion/imunologia
7.
Pediatrics ; 144(4)2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31530719

RESUMO

BACKGROUND: Rotavirus vaccine has been funded for infants under the Australian National Immunisation Program since 2007, with Rotarix vaccine used in New South Wales, Australia, from that time. In 2017, New South Wales experienced a large outbreak of rotavirus gastroenteritis. We examined epidemiology, genotypic profiles, and vaccine effectiveness (VE) among cases. METHODS: Laboratory-confirmed cases of rotavirus notified in New South Wales between January 1, 2010 and December 31, 2017 were analyzed. VE was estimated in children via a case-control analysis. Specimens from a sample of hospitalized case patients were genotyped and analyzed. RESULTS: In 2017, 2319 rotavirus cases were reported, representing a 3.1-fold increase on the 2016 notification rate. The highest rate was among children aged <2 years. For notified cases in 2017, 2-dose VE estimates were 88.4%, 83.7%, and 78.7% in those aged 6 to 11 months, 1 to 3 years, and 4 to 9 years, respectively. VE was significantly reduced from 89.5% within 1 year of vaccination to 77.0% at 5 to 10 years postvaccination. Equinelike G3P[8] (48%) and G8P[8] (23%) were identified as the most common genotypes in case patients aged ≥6 months. CONCLUSIONS: Rotarix is highly effective at preventing laboratory-confirmed rotavirus in Australia, especially in infants aged 6 to 11 months. Reduced VE in older age groups and over time suggests waning protection, possibly related to the absence of subclinical immune boosting from continuously circulating virus. G8 genotypes have not been common in Australia, and their emergence, along with equinelike G3P[8], may be related to vaccine-induced selective pressure; however, further strain-specific VE studies are needed.


Assuntos
Surtos de Doenças , Gastroenterite/epidemiologia , Infecções por Rotavirus/epidemiologia , Vacinas contra Rotavirus/uso terapêutico , Rotavirus/genética , Adolescente , Adulto , Distribuição por Idade , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Criança , Pré-Escolar , Notificação de Doenças/estatística & dados numéricos , Feminino , Gastroenterite/imunologia , Gastroenterite/prevenção & controle , Genótipo , Humanos , Programas de Imunização , Imunogenicidade da Vacina , Lactente , Masculino , Pessoa de Meia-Idade , New South Wales/epidemiologia , Rotavirus/imunologia , Infecções por Rotavirus/imunologia , Infecções por Rotavirus/prevenção & controle , Resultado do Tratamento , Vacinas Atenuadas/uso terapêutico , Adulto Jovem
8.
Mucosal Immunol ; 12(6): 1259-1267, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31501514

RESUMO

Noroviruses are major causes of gastroenteritis, with epidemic outbreaks occurring frequently. They are an important global health concern, especially for pediatric and immunocompromised populations, and are challenging pathogens to target immunologically due to their rapid rates of genetic and antigenic evolution and failure to stimulate durable protective immunity. In this Review, we summarize our current understanding of norovirus pathogenesis, noting the prominent role of murine norovirus as a small animal model for norovirus research. We highlight intriguing data supporting the possible involvement of norovirus in sequelae including irritable bowel syndrome and inflammatory bowel diseases, and describe the innate and adaptive immune mechanisms involved in control of both human and murine norovirus infection. Furthermore, we discuss the potential implications of recent discoveries regarding norovirus interactions with the gut microbiota, and briefly detail current understanding of noroviral evolution and its influence on viral pathogenesis. Our mechanistic understanding of norovirus pathogenesis continues to improve with increasing availability of powerful model systems, which will ultimately facilitate development of effective preventive and therapeutic approaches for this pathogen.


Assuntos
Infecções por Caliciviridae/virologia , Gastroenterite/virologia , Imunidade nas Mucosas , Mucosa Intestinal/virologia , Norovirus/patogenicidade , Imunidade Adaptativa , Animais , Infecções por Caliciviridae/imunologia , Modelos Animais de Doenças , Gastroenterite/imunologia , Microbioma Gastrointestinal , Interações Hospedeiro-Patógeno , Humanos , Imunidade Inata , Mucosa Intestinal/imunologia , Mucosa Intestinal/microbiologia , Norovirus/imunologia
9.
Vaccine ; 37(39): 5886-5890, 2019 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-31451325

RESUMO

INTRODUCTION: Because of the large animal reservoirs and reassortment capacity of rotaviruses (RVs) that pose the possibilities of waning the effectiveness of RV-vaccines, it remains essential to monitor vaccine effectiveness (VE) regularly. Although reverse transcription polymerase chain reaction (RT-PCR) remains sensitive for RV detection, physicians, especially in Japan, frequently use immunochromatography (IC)-based kits for RV diagnosis. Recently, IC is being used to calculate VE also. Herein, we investigated the validity of VEs determined by IC compared to that by RT-PCR during an outbreak in Shizuoka Prefecture, Japan. METHODS: RVs in the stool or rectal swabs from children with acute gastroenteritis (AGE) were tested first by IC in the clinic and then by RT-PCR in the laboratory. A test-negative study design was used to examine VE. RESULTS: Although the specificity of IC assay revealed 100%, its sensitivity remained weaker (67%) than that of RT-PCR that increased up to 88% depending on disease severity. VE assessed by IC remained stronger than that by RT-PCR: 79% (95% CI: 39-93%) by IC, and 58% (95% CI: -20% to 90%) by RT-PCR. However, VEs by IC and RT-PCR appeared almost similar in higher disease severity: 81.5% (95% CI: 40-94%) by IC and 72% (95% CI: 7-92%) by RT-PCR at severity ≥7, while 97.5% (95% CI: 77-99.7%) by IC and 92% (95% CI: 58-98%) by RT-PCR at severity ≥11. We showed that RV-vaccinated children had 80% [OR = 0.192 (95% CI: 0.052-0.709) less chance to be detected by IC. CONCLUSION: Although the sensitivity and specificity of IC differ by brand type, generally, IC is not as sensitive as RT-PCR. Despite the VEs remain higher by IC, it looks comparable with that of RT-PCR in severe cases implying that VEs evaluated by IC against severe illness remain useful for VE-monitoring.


Assuntos
Infecções por Rotavirus/imunologia , Infecções por Rotavirus/prevenção & controle , Vacinas contra Rotavirus/imunologia , Rotavirus/imunologia , Pré-Escolar , Cromatografia de Afinidade/métodos , Fezes/virologia , Feminino , Gastroenterite/imunologia , Humanos , Lactente , Recém-Nascido , Japão , Masculino , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Sensibilidade e Especificidade , Vacinação/métodos
10.
PLoS One ; 14(7): e0220387, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31361761

RESUMO

Group A rotaviruses (RVA) are one of the major causes of acute gastroenteritis (AGE) in young children worldwide. Owing to lack of proper surveillance programs and health facilities, developing countries of Asia and Africa carry a disproportionately heavy share of the RVA disease burden. The aim of this hospital-based study was to investigate the circulation of RVA genotypes in Rawalpindi and Islamabad, Pakistan in 2015 and 2016, prior to the implementation of RVA vaccine. 639 faecal samples collected from children under 10 years of age hospitalized with AGE were tested for RVA antigen by ELISA. Among 171 ELISA positive samples, 143 were successfully screened for RT-PCR and sequencing. The prevalence of RVA was found to be 26.8% with the highest frequency (34.9%) found among children of age group 6-11 months. The most predominant circulating genotypes were G3P[8] (22.4%) followed by G12P[6] (20.3%), G2P[4] (12.6%), G1P[8] (11.9%), G9P[6] (11.9%), G3P[4] (9.1%), G1P[6] (4.2%), G9P[8] (4.2%), and G3P[6] (0.7%). A single mixed genotype G1G3P[8] was also detected. The findings of this study provide baseline data, that will help to assess if future vaccination campaigns using currently available RVA vaccine will reduce RVA disease burden and instigate evolutionary changes in the overall RVA biology. The high prevalence of RVA infections in Pakistan require to improve and strengthen the surveillance and monitoring system for RVA. This will provide useful information for health authorities in planning public health care strategies to mitigate the disease burden caused by RVA.


Assuntos
Gastroenterite/virologia , Infecções por Rotavirus/epidemiologia , Rotavirus/classificação , Análise de Sequência de DNA/métodos , Antígenos Virais/metabolismo , Criança , Pré-Escolar , Fezes/virologia , Feminino , Gastroenterite/imunologia , Genótipo , Humanos , Lactente , Recém-Nascido , Masculino , Paquistão/epidemiologia , Filogenia , Prevalência , Rotavirus/genética , Rotavirus/imunologia , Infecções por Rotavirus/imunologia , Infecções por Rotavirus/virologia
11.
PLoS One ; 14(7): e0215883, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31291255

RESUMO

Innate CD8αα+ cells, also referred to as iCD8α cells, are TCR-negative intraepithelial lymphocytes (IEL) possessing cytokine and chemokine profiles and functions related to innate immune cells. iCD8α cells constitute an important source of osteopontin in the intestinal epithelium. Osteopontin is a pleiotropic cytokine with diverse roles in bone and tissue remodeling, but also has relevant functions in the homeostasis of immune cells. In this report, we present evidence for the role of iCD8α cells in the homeostasis of TCR-negative NKp46+NK1.1+ IEL (ILC1-like). We also show that the effect of iCD8α cells on ILC1-like IEL is enhanced in vitro by osteopontin. We show that in the absence of iCD8α cells, the number of NKp46+NK1.1+ IEL is significantly reduced. These ILC1-like cells are involved in intestinal pathogenesis in the anti-CD40 mouse model of intestinal inflammation. Reduced iCD8α cell numbers results in a milder form of intestinal inflammation in this disease model, whereas treatment with osteopontin increases disease severity. Collectively, our results suggest that iCD8α cells promote survival of NKp46+NK1.1+ IEL, which significantly impacts the development of intestinal inflammation.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Mucosa Intestinal/imunologia , Linfócitos Intraepiteliais/imunologia , Animais , Antígenos CD8/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Linfócitos T CD8-Positivos/patologia , Sobrevivência Celular/imunologia , Gastroenterite/etiologia , Gastroenterite/imunologia , Gastroenterite/patologia , Homeostase/imunologia , Imunidade Inata , Mucosa Intestinal/patologia , Linfócitos Intraepiteliais/metabolismo , Linfócitos Intraepiteliais/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Osteopontina/metabolismo , Receptores de Antígenos de Linfócitos T/metabolismo
12.
Curr Opin Infect Dis ; 32(5): 445-452, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31335438

RESUMO

PURPOSE OF REVIEW: Gastroenteritis results in substantial morbidity and mortality worldwide, especially in young children in low-and-middle-income settings. Rotavirus and norovirus are the leading causes of viral gastroenteritis. Although introduction of rotavirus vaccines into childhood immunization programmes has reduced disease burden, vaccine effectiveness remains low in developing countries. Norovirus is replacing rotavirus as the most common cause of diarrhea hospitalization in settings where rotavirus vaccines are highly effective. Genetically determined host factors, such as expression of histo blood group antigens (HBGAs) are hypothesized to play key roles in susceptibility to infections and gastroenteritis caused by these virus, as well as influence vaccine take. RECENT FINDINGS: Epidemiology studies provide strong support for virus genotype-dependent effects of host HBGA expression, specifically secretor status on susceptibility to rotavirus and norovirus. Secretor-positive persons are significantly more susceptible to gastroenteritis caused by rotavirus P[8] genotype, and to infection with the GII.4 genotype of human norovirus. There is increasing data on the role of secretor status on rotavirus vaccine take but results are currently conflicting. For analyses involving young infants, maternal HBGA status is an important factor to be considered in future studies. SUMMARY: Genetically determined HBGA expression influences susceptibility to enteric viruses of public health importance.


Assuntos
Antígenos de Grupos Sanguíneos/biossíntese , Infecções por Caliciviridae/epidemiologia , Suscetibilidade a Doenças , Gastroenterite/epidemiologia , Infecções por Rotavirus/epidemiologia , Infecções por Caliciviridae/imunologia , Gastroenterite/imunologia , Gastroenterite/virologia , Expressão Gênica , Humanos , Infecções por Rotavirus/imunologia
14.
BMC Pediatr ; 19(1): 193, 2019 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-31189470

RESUMO

BACKGROUND: Rotavirus antigenemia and RNAemia (the presence of rotavirus RNA in serum) have been commonly identified among paediatric patients with acute gastroenteritis. In this study we examined the association between rotavirus antigenemia and clinical features, and sought to determine the genotypes of rotaviruses detected in paired stool and serum samples. METHODS: Paired stool and serum samples were obtained from children hospitalised for acute gastroenteritis in Belém, Brazil, between June 2012 and June 2015. The 20-point Vesikari scoring system was used to assess the disease severity upon a retrospective medical record review. Stool and serum samples were primarily screened for the presence of rotavirus antigen using a commercial ELISA assay. The rotavirus isolates from stool and serum samples were genotyped by using the classical reverse-transcriptase polymerase chain reaction (RT-PCR) and/or through nucleotide sequencing of VP4 and VP7 genes. Viral load was estimated using real-time RT-PCR. RESULTS: In total rotavirus antigen was detected in 109 (24.2%) stool samples from 451 children, whereas antigenemia occurred in 38.5% (42/109) of these patients. We demonstrated that patients positive for rotavirus RNA in paired stool and serum samples were more likely to have a higher frequency of vomiting episodes in a 24-h period (p = 0.0035). Our findings also suggested that children not vaccinated against rotavirus are more likely to develop antigenemia, as compared to those given at least one vaccine dose (p = 0.0151). G12P [8] and G2P [4] genotypes were predominant throughout the study period, accounting for 52.3% (57/109) and 27.5% (30/109) of the typed isolates, respectively. Ten stool-serum pairs could be typed for VP4 and VP7 genes. Seven of these pairs showed concordant results with G2P [4] genotype being detected in stool and serum samples, whereas discrepancies between genotypes (G2P [4]/G2P[NT] and G12P [8]/G2P[NT]) were seen in three pairs. CONCLUSIONS: Rotavirus antigenemia and RNAemia occur in a significant number of children hospitalised for acute gastroenteritis in Belém, Brazil, and may contribute to a greater disease severity, particularly translated into a greater number of vomiting episodes. This study documented a high concordance of genotypes detected in a subgroup of paired stool and serum samples.


Assuntos
Antígenos Virais/análise , Gastroenterite/imunologia , RNA Viral/análise , Infecções por Rotavirus/imunologia , Rotavirus/imunologia , Doença Aguda , Antígenos Virais/sangue , Brasil , Criança , Pré-Escolar , Ensaio de Imunoadsorção Enzimática , Fezes/química , Fezes/virologia , Feminino , Gastroenterite/complicações , Gastroenterite/virologia , Genótipo , Hospitalização , Humanos , Masculino , Estudos Prospectivos , RNA Viral/sangue , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Rotavirus/genética , Índice de Gravidade de Doença , Vômito/etiologia
15.
Curr Opin Virol ; 37: 10-15, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31163291

RESUMO

Although astroviruses are most commonly associated with acute gastrointestinal illness in humans, their ability to infect a broad range of hosts and cause a spectrum of disease makes them widespread and complex pathogens. The precise mechanisms that dictate the course of astrovirus disease have not been studied extensively but are likely driven by multifactorial host-microbe interactions. Recent insights from studies of animal astrovirus infections have revealed both beneficial and detrimental effects for the host. However, further in-depth studies are needed to fully explore the consequences of astrovirus-induced changes in the gut microenvironment as well as the role of the microbiota in astrovirus infection.


Assuntos
Infecções por Astroviridae , Gastroenterite , Mamastrovirus/patogenicidade , Interações Microbianas , Animais , Astroviridae/patogenicidade , Infecções por Astroviridae/imunologia , Infecções por Astroviridae/microbiologia , Aves/microbiologia , Aves/virologia , Quirópteros/microbiologia , Quirópteros/virologia , Gastroenterite/imunologia , Gastroenterite/microbiologia , Gastroenterite/virologia , Microbioma Gastrointestinal/imunologia , Interações entre Hospedeiro e Microrganismos , Humanos , Camundongos , Vírus de RNA
16.
Arch Virol ; 164(8): 2107-2117, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31144039

RESUMO

Species A rotavirus still remains a major cause of acute gastroenteritis in infants and young children. Globally, six genotypes (G1P[8], G2P[4], G3P[8], G4P[8], G9P[8] and G12P[8]) account for >90% of circulating strains; however, genotype G12 in combination with P[6] or P[9] has been detected at increasing rates. We sought to broaden our knowledge about the rotavirus strains circulating during the early post-vaccine-introduction period. Stool samples were obtained from children hospitalised for acute gastroenteritis in Belém, Northern Brazil, from May 2008 to May 2011 and examined by reverse transcription polymerase chain reaction and nucleotide sequencing. A total of 122 out of the original 1076 rotavirus strains were judged to be non-typeable in the first analysis and were therefore re-examined. G2P[4] was the most prevalent genotype (58.0%), followed by G1P[8] (16.9%), and G12P[6] (7.5%). G12P[6] strains were identified at similar rates during the first (2.5%) and second (3.9%) years, and the rate jumped to 15.6% in the third year. Analysis of VP7 sequences of the G12P[6] strains showed that they belonged to lineage III. In addition, co-circulating G12P[6] strains displaying long and short RNA patterns were found to belong to the Wa-like and DS-1-like constellation, respectively. Additional unusual circulating strains G12P[9] and G3P[9] were also identified. This hospital-based study showed a high prevalence of G12P[6] strains in the third year of surveillance. Our results highlight the need for continuous longitudinal monitoring of circulating rotavirus strains after introduction of rotavirus vaccines in Brazil and elsewhere.


Assuntos
Gastroenterite/virologia , Rotavirus/genética , Antígenos Virais/imunologia , Brasil , Criança , Criança Hospitalizada , Gastroenterite/imunologia , Genótipo , Humanos , Epidemiologia Molecular/métodos , Filogenia , Prevalência , RNA Viral/genética , Rotavirus/imunologia , Infecções por Rotavirus/imunologia , Infecções por Rotavirus/virologia , Vacinas contra Rotavirus/imunologia , Análise de Sequência de DNA/métodos
17.
Int J Mol Sci ; 20(10)2019 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-31126070

RESUMO

A correlation between gastrointestinal (GI) inflammation and gut hormones has reported that inflammatory stimuli including bacterial endotoxins, lipopolysaccharides (LPS), TNFα, IL-1ß, and IL-6 induces high levels of incretin hormone leading to glucose dysregulation. Although incretin hormones are immediately secreted in response to environmental stimuli, such as nutrients, cytokines, and LPS, but studies of glucose-induced incretin secretion in an inflamed state are limited. We hypothesized that GI inflammatory conditions induce over-stimulated incretin secretion via an increase of glucose-sensing receptors. To confirm our hypothesis, we observed the alteration of glucose-induced incretin secretion and glucose-sensing receptors in a GI inflammatory mouse model, and we treated a conditioned media (Mϕ 30%) containing inflammatory cytokines in intestinal epithelium cells and enteroendocrine L-like NCI-H716 cells. In GI-inflamed mice, we observed that over-stimulated incretin secretion and insulin release in response to glucose and sodium glucose cotransporter (Sglt1) was increased. Incubation with Mϕ 30% increases Sglt1 and induces glucose-induced GLP-1 secretion with increasing intracellular calcium influx. Phloridzin, an sglt1 inhibitor, inhibits glucose-induced GLP-1 secretion, ERK activation, and calcium influx. These findings suggest that the abnormalities of incretin secretion leading to metabolic disturbances in GI inflammatory disease by an increase of Sglt1.


Assuntos
Gastroenterite/imunologia , Glucose/imunologia , Insulina/imunologia , Transportador 1 de Glucose-Sódio/imunologia , Animais , Linhagem Celular , Células Cultivadas , Feminino , Polipeptídeo Inibidor Gástrico/imunologia , Gastroenterite/patologia , Peptídeo 1 Semelhante ao Glucagon/imunologia , Incretinas/imunologia , Inflamação/imunologia , Inflamação/patologia , Mucosa Intestinal/imunologia , Mucosa Intestinal/patologia , Camundongos Endogâmicos C57BL
18.
Viruses ; 11(5)2019 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-31083353

RESUMO

Human norovirus (HuNoV) is the leading cause of acute nonbacterial gastroenteritis. Vaccine design has been confounded by the antigenic diversity of these viruses and a limited understanding of protective immunity. We reviewed 77 articles published since 1988 describing the isolation, function, and mapping of 307 unique monoclonal antibodies directed against B cell epitopes of human and murine noroviruses representing diverse Genogroups (G). Of these antibodies, 91, 153, 21, and 42 were reported as GI-specific, GII-specific, MNV GV-specific, and G cross-reactive, respectively. Our goal was to reconstruct the antigenic topology of noroviruses in relationship to mapped epitopes with potential for therapeutic use or inclusion in universal vaccines. Furthermore, we reviewed seven published studies of norovirus T cell epitopes that identified 18 unique peptide sequences with CD4- or CD8-stimulating activity. Both the protruding (P) and shell (S) domains of the major capsid protein VP1 contained B and T cell epitopes, with the majority of neutralizing and HBGA-blocking B cell epitopes mapping in or proximal to the surface-exposed P2 region of the P domain. The majority of broadly reactive B and T cell epitopes mapped to the S and P1 arm of the P domain. Taken together, this atlas of mapped B and T cell epitopes offers insight into the promises and challenges of designing universal vaccines and immunotherapy for the noroviruses.


Assuntos
Epitopos de Linfócito T/imunologia , Gastroenterite/prevenção & controle , Norovirus/imunologia , Vacinas Virais/imunologia , Animais , Anticorpos Antivirais/imunologia , Proteínas do Capsídeo/química , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/imunologia , Mapeamento de Epitopos , Epitopos de Linfócito T/química , Epitopos de Linfócito T/genética , Gastroenterite/imunologia , Gastroenterite/virologia , Humanos , Norovirus/química , Norovirus/genética , Vacinas Virais/química , Vacinas Virais/genética
19.
World J Gastroenterol ; 25(15): 1899-1906, 2019 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-31057303

RESUMO

BACKGROUND: Cytomegalovirus (CMV) remains a critical complication after solid-organ transplantation. The CMV antigenemia (AG) test is useful for monitoring CMV infection. Although the AG-positivity rate in CMV gastroenteritis is known to be low at onset, almost all cases become positive during the disease course. We treated a patient with transverse colon perforation due to AG-negative CMV gastroenteritis, following a living donor liver transplantation (LDLT). CASE SUMMARY: The patient was a 52-year-old woman with decompensated liver cirrhosis as a result of autoimmune hepatitis who underwent a blood-type compatible LDLT with her second son as the donor. On day 20 after surgery, upper and lower gastrointestinal endoscopy (GE) revealed multiple gastric ulcers and transverse colon ulcers. The biopsy tissue immunostaining confirmed a diagnosis of CMV gastroenteritis. On day 28 after surgery, an abdominal computed tomography revealed transverse colon perforation, and simple lavage and drainage were performed along with an urgent ileostomy. Although the repeated remission and aggravation of CMV gastroenteritis and acute cellular rejection made the control of immunosuppression difficult, the upper GE eventually revealed an improvement in the gastric ulcers, and the biopsy samples were negative for CMV. The CMV-AG test remained negative, therefore, we had to evaluate the status of the CMV infection on the basis of the clinical symptoms and GE. CONCLUSION: This case report suggests a monitoring method that could be useful for AG-negative CMV gastroenteritis after a solid-organ transplantation.


Assuntos
Doenças do Colo/diagnóstico , Infecções por Citomegalovirus/complicações , Gastroenterite/complicações , Perfuração Intestinal/diagnóstico , Transplante de Fígado/efeitos adversos , Antígenos Virais/sangue , Antígenos Virais/imunologia , Colo/diagnóstico por imagem , Colo/virologia , Doenças do Colo/etiologia , Citomegalovirus/imunologia , Citomegalovirus/isolamento & purificação , Infecções por Citomegalovirus/sangue , Infecções por Citomegalovirus/imunologia , Infecções por Citomegalovirus/virologia , Doença Hepática Terminal/imunologia , Doença Hepática Terminal/patologia , Doença Hepática Terminal/cirurgia , Endoscopia Gastrointestinal , Feminino , Gastroenterite/sangue , Gastroenterite/imunologia , Gastroenterite/virologia , Hepatite Autoimune/imunologia , Hepatite Autoimune/patologia , Hepatite Autoimune/cirurgia , Humanos , Perfuração Intestinal/etiologia , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X
20.
Nat Microbiol ; 4(7): 1120-1128, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30936486

RESUMO

Commensal microbes profoundly impact host immunity to enteric viral infections1. We have shown that the bacterial microbiota and host antiviral cytokine interferon-λ (IFN-λ) determine the persistence of murine norovirus in the gut2,3. However, the effects of the virome in modulating enteric infections remain unexplored. Here, we report that murine astrovirus can complement primary immunodeficiency to protect against murine norovirus and rotavirus infections. Protection against infection was horizontally transferable between immunocompromised mouse strains by co-housing and fecal transplantation. Furthermore, protection against enteric pathogens corresponded with the presence of a specific strain of murine astrovirus in the gut, and this complementation of immunodeficiency required IFN-λ signalling in gut epithelial cells. Our study demonstrates that elements of the virome can protect against enteric pathogens in an immunodeficient host.


Assuntos
Infecções por Caliciviridae/prevenção & controle , Gastroenterite/prevenção & controle , Trato Gastrointestinal/virologia , Hospedeiro Imunocomprometido , Interferons/metabolismo , Norovirus/imunologia , Animais , Astroviridae/classificação , Astroviridae/genética , Astroviridae/isolamento & purificação , Astroviridae/fisiologia , Infecções por Caliciviridae/imunologia , Infecções por Caliciviridae/virologia , Transplante de Microbiota Fecal , Fezes/virologia , Feminino , Gastroenterite/imunologia , Gastroenterite/virologia , Trato Gastrointestinal/metabolismo , Mucosa Intestinal/metabolismo , Masculino , Camundongos , Transdução de Sinais , Eliminação de Partículas Virais
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