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BACKGROUND: Children with refractory constipation experience intense and persistent symptoms that greatly diminish their quality of life. However, the underlying pathophysiological mechanism responsible for this condition remains uncertain. Our objective was to evaluate characteristics of colonic motor patterns and interstitial cells of Cajal (ICCs) to refractory constipation children, as well as intestinal microbiota compositions. METHODS: Colonic manometry (CM) was conducted on a cohort of 30 patients with refractory constipation to assess colonic motility, and 7 of them underwent full-thickness colon biopsy specimens. Another 5 colonic specimens from nonconstipation patients were collected to identify the ICCs by immunohistochemistry. Fecal samples from 14 children diagnosed with refractory constipation and subjecting 28 age-matched healthy children to analysis using high-throughput sequencing of 16S rRNA. RESULTS: According to CM results, dividing 30 children with refractory constipation into 2 groups: normal group (n = 10) and dysmotility group (n = 20). Dysmotility subjects showed lower colonic motility. Antegrade propagating pressure waves, retrograde propagating pressure waves, and periodic colonic motor activity were common in normal subjects and rare in dysmotility subjects (32.7 ± 8.9 vs 20.7 ± 13.0/17 h, P < 0.05, 11.5 ± 2.3 vs 9.6 ± 2.3/17 h, P < 0.05, and 5.2 ± 8.9 vs 3.5 ± 6.8 cpm, P < 0.005, respectively), whereas periodic rectal motor activity was more common in dysmotility subjects (3.4 ± 4.8 vs 3.0 ± 3.1 cpm, P < 0.05). Dysmotility subjects exhibited a significantly greater number of preprandial simultaneous pressure waves compared to the normal subjects (32.3 ± 25.0 vs 23.6 ± 13.2/1 h, P < 0.005). Dysmotility subjects displayed a notable decrease in postprandial count of antegrade propagating pressure waves and high amplitude propagating pressure waves when compared to normal subjects (3.9 ± 2.9 vs 6.9 ± 3.5/1 h and 2.3 ± 1.5 vs 5.4 ± 2.9/1 h, respectively, P < 0.05). The number, distribution, and morphology of ICCs were markedly altered in refractory constipation compared children to the controls (P < 0.05). Children diagnosed with refractory constipation displayed a distinct dissimilarity in composition of their intestinal microbiota comparing with control group (P < 0.005). In genus level, Bacteroidetes represented 34.34% and 43.78% in the refractory constipation and control groups, respectively. Faecalibacterium accounted for 3.35% and 12.56%, respectively (P < 0.005). Furthermore, the relative abundances of Faecalibacterium (P < 0.005), Lachnospira (P < 0.05), and Haemophilus (P < 0.05) significantly decreased, whereas those of Parabacteroides (P < 0.05), Alistipes (P < 0.005), Prevotella_2 (P < 0.005), [Ruminococcus]_torques_group (P < 0.005), Barnesiella (P < 0.05), Ruminococcaceae_UCG-002 (P < 0.005), and Christensensenellaceae_R-7_group (P < 0.05) were markedly increased in children with refractory constipation. CONCLUSIONS: Dysmotility subjects showed lower colonic motility and an impaired postprandial colonic response. The decreased number and abnormal morphology of colonic ICCs may contribute to the pathogenesis of refractory constipation. Children with refractory constipation exhibited significant variations in microbiota composition across various taxonomic levels compared to the healthy control group. Our findings contribute valuable insights into pathophysiological mechanism underlying refractory constipation and provide evidence to support the exploration of novel therapeutic strategies for affected children.
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Microbioma Gastrointestinal , Células Intersticiais de Cajal , Humanos , Criança , Células Intersticiais de Cajal/patologia , Qualidade de Vida , RNA Ribossômico 16S/genética , Constipação Intestinal/diagnóstico , Constipação Intestinal/patologia , Colo/patologia , BacteroidetesRESUMO
Inspired by the structure of eukaryotic cells, multicompartmental microcapsules have gained increasing attention. However, challenges remain in the fabrication of "all-aqueous" (i.e., oil-free) microcapsules composed of accurately adjustable hierarchical compartments. This study reports on multicompartmental microcapsules with an innovative architecture. While multicompartmental cores of the microcapsules were fabricated through gas shearing, a shell was applied on the cores through surface gelation of alginate. Different from traditional multicompartmental microcapsules, thus obtained microcapsules have well-segregated compartments while the universal nature of the surface-gelation method allows us to finely tune the shell thicknesses of the microcapsules. The microcapsules are highly stable and cytocompatible and allow repeated enzymatic cascade reactions, which might make them of interest for complex biocatalysis or for mimicking physiological processes.
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Alginatos , Água , Alginatos/química , Cápsulas/química , Emulsões/químicaRESUMO
Human caliciviruses (HuCVs) have been recognized as a major cause of sporadic viral diarrhea in children, among which norovirus genotype GII.4 is the most prevalent genotype. Stool and saliva samples were collected from 295 children with acute diarrhea and 150 asymptomatic children at a hospital in China. The HuCV detection rate was 10.85% (32/295) among the children with acute diarrhea, and all of these 32 children were either HBGA secretors (12/32) or partial secretors (20/32). HuCV was detected in two (1.33%) of the 150 samples obtained from the asymptomatic children. Of the norovirus-GII.3-positive children, 60% had blood type O, but only 17.29% of the symptomatic patients had blood type O, indicating that type O individuals could be at higher risk of GII.3 infection. However, due to the limited number of individuals in this study, further studies with a larger number of subjects should be conducted to verify this hypothesis.
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Antígenos de Grupos Sanguíneos/genética , Infecções por Caliciviridae/virologia , Norovirus , Antígenos de Grupos Sanguíneos/imunologia , Infecções por Caliciviridae/epidemiologia , Infecções por Caliciviridae/imunologia , Estudos de Casos e Controles , Pré-Escolar , China/epidemiologia , Diarreia/epidemiologia , Diarreia/virologia , Feminino , Gastroenterite/epidemiologia , Gastroenterite/virologia , Predisposição Genética para Doença , Humanos , Lactente , MasculinoRESUMO
Human health is under growing threat from the increasing incidence of bacterial infections. Through their antimicrobial mechanisms, bacteria use appropriate strategies to overcome the antimicrobial effects of antibiotics. The enhanced effects of synergistic strategies on drug-resistant bacteria and biofilms have led to increasing interest in these approaches in recent years. Herein, biomimetic hydroxyethyl cellulose @ Prussian blue microparticles (HEC@PB MPs) generated by the gas-shearing method show a synergistic antibacterial property induced by antibiotic-, photothermal- and photodynamic- effect. MPs, as tri-modality antibacterial agents, exhibit ideal antibacterial activity and biofilm removal effect, and their mode of action on bacteria was investigated. Additionally, a drug release concept encouraged by the ROS-driven breakdown of cellulose, as seen in brown-rot fungi, was introduced. It combines ROS-responsive HEC and photodynamic PB and is likely to fit a niche in many applications.
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Copper ions (Cu2+) pose significant risks to both human health and the environment as they tend to accumulate in soil and water. To address this issue, an innovative method using biomass-derived fluorescent carbon dots (D-CDs) synthesized via a hydrothermal process, with xylan serving as the carbon source was developed. D-CDs solution exhibited remarkable sensitivity and selectivity as a fluorescence sensor for Cu2+, boasting a low detection threshold of 0.64 µM. In order to facilitate real-time monitoring of Cu2+, solid-state fluorescent nanofiber membrane (NFD-CDs) through electrospinning was engineered. Additionally, D-CDs demonstrated successful Cu2+ detection in various real water samples, including those sourced from Xuanwu Lake, the Yangtze River, tap water, and bottled water, with accurate recovery rates observed. As a result, this research introduces a dual-mode analytical system for onsite detection of Cu2+ in real scenarios. By harnessing biomass-derived fluorescent CDs materials and solid-state fluorescence sensors, this approach offers a promising solution for addressing the challenges associated with Cu2+ contamination.
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BACKGROUND AND AIMS: Cholestatic liver disease is a leading referral to pediatric liver transplant centers. Inherited disorders are the second most frequent cause of cholestasis in the first month of life. METHODS: We retrospectively characterized the genotype and phenotype of 166 participants with intrahepatic cholestasis, and re-analyzed phenotype and whole-exome sequencing (WES) data from patients with previously undetermined genetic etiology for newly published genes and novel candidates. Functional validations of selected variants were conducted in cultured cells. RESULTS: Overall, we identified disease-causing variants in 31% (52/166) of our study participants. Of the 52 individuals, 18 (35%) had metabolic liver diseases, 9 (17%) had syndromic cholestasis, 9 (17%) had progressive familial intrahepatic cholestasis, 3 (6%) had bile acid synthesis defects, 3(6%) had infantile liver failure and 10 (19%) had a phenocopy of intrahepatic cholestasis. By reverse phenotyping, we identified a de novo variant c.1883G > A in FAM111B of a case with high glutamyl transpeptidase (GGT) cholestasis. By re-analyzing WES data, two patients were newly solved, who had compound heterozygous variants in recently published genes KIF12 and USP53, respectively. Our additional search for novel candidates in unsolved WES families revealed four potential novel candidate genes (NCOA6, CCDC88B, USP24 and ATP11C), among which the patients with variants in NCOA6 and ATP11C recapitulate the cholestasis phenotype in mice models. CONCLUSIONS: In a single-center pediatric cohort, we identified monogenic variants in 22 known human intrahepatic cholestasis or phenocopy genes, explaining up to 31% of the intrahepatic cholestasis patients. Our findings suggest that re-evaluating existing WES data from well-phenotyped patients on a regular basis can increase the diagnostic yield for cholestatic liver disease in children.
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Colestase Intra-Hepática , Colestase , Proteínas de Membrana Transportadoras , Criança , Humanos , Animais , Camundongos , Estudos Retrospectivos , Sequenciamento de Nucleotídeos em Larga Escala , Colestase Intra-Hepática/genética , Colestase Intra-Hepática/diagnóstico , Mutação , Cinesinas/genética , Ubiquitina Tiolesterase/genética , Proteases Específicas de Ubiquitina/genética , Proteínas de Ciclo Celular/genética , Adenosina Trifosfatases/genéticaRESUMO
Corrosion damage in reinforcing steel bars has been a major cause of cracking and spalling of reinforced concrete. To extend the service life of concrete structures, non-destructive testing methods are necessary to assess the corrosion status in order to conduct a timely repair. At the early stage of corrosion, rust grows from the reinforcing bar, subsequently generates cracks towards the surface of the concrete. Ultrasonic methods have been widely used to detect cracks in concrete. However, it is challenging to characterise them due to the heterogeneous material properties of the concrete. In this paper, ultrasonic imaging technique based on diffuse coda wave has been explored to inspect and characterise corrosion-induced cracks. In this method, scattering cross-section of the crack is reconstructed with the Locadiff imaging technique. Based on the assumption that both crack tips have the same scattering cross-section, the size of the crack can be estimated when the location of the reinforcing bar is known. Numerical simulations were carried out to image straight and curved cracks, showing excellent accuracy. Experiments were designed subsequently on concrete samples with accelerated corrosion. The induced cracks were characterised by the proposed ultrasonic method, and compared with X-ray CT results, showing very good agreement.
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Bacterial infections pose a serious threat to public health, causing worldwide morbidity and about 80 % of bacterial infections are related to biofilm. Removing biofilm without antibiotics remains an interdisciplinary challenge. To solve this problem, we presented a dual-power driven antibiofilm system Prussian blue composite microswimmers based on alginate-chitosan, which designed into an asymmetric structure to achieve self-driven in the fuel solution and magnetic field. Prussian blue embedded in the microswimmers given it the ability to convert light and heat, catalyze Fenton reaction, and produce bubbles and reactive oxygen species. Moreover, with the addition of Fe3O4, the microswimmers could move in group under external magnetic field. The composite microswimmers displayed excellent antibacterial activity against S. aureus biofilm with an efficiency as high as 86.94 %. It is worth mentioning that the microswimmers were fabricated with device-simple and low-cost gas-shearing method. This system integrating physical destruction, chemical damage such chemodynamic therapy and photothermal therapy, and finally kill the plankton bacteria embedded in biofilm. This approach may cause an autonomous, multifunctional antibiofilm platform to promote the present most areas with harmful biofilm difficult to locate the surface for removal.
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Quitosana , Quitosana/farmacologia , Quitosana/química , Alginatos , Staphylococcus aureus , Antibacterianos/farmacologia , Antibacterianos/química , BiofilmesRESUMO
Picric acid (PA) is highly water-soluble, the fact makes it stand out as the most hazardous environment pollutant. Therefore, accurate determination of PA is of great significance for human health and environmental protection. Herein, a novel indole-based fluorescent sensor (H1) with good water solubility and fluorescence stability was reported. H1 exhibited 'turn-off' fluorescence response for PA with fast reaction rate (<30 s), unique specificity and excellent selectivity and high sensitivity (limit of detection = 34 nM). Further, H1 was successfully applied to detect PA in real samples (tap water, Yangtze River, Xuanwu Lake, soil, food, fish and shrimp) with satisfactory recoveries at three spiking levels ranging from 98.0 to 112.0 %. In addition, H1 displayed high biocompatibility in mung beans and fresh blood. Moreover, aiming to attain portable analysis, H1 was composited with biomass cellulose paper (H1-FP) and integrated with smartphone for construction as a solid-state fluorescence platform to achieve fast and visual detection of PA in suit with significant stability, high sensitively and selectivity. The establishment of this sensing approach is expected to offer new insight into rapid, selective, and sensitive detection of major pollutants for food and environmental safety.
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Celulose , Poluentes Ambientais , Humanos , Biomassa , Espectrometria de Fluorescência , Água , Corantes FluorescentesRESUMO
The emergence, spread and difficult removal of bacteria biofilm, represent an ever-increasing persistent infections and medical complications challenge worldwide. Herein, a self-propelled system Prussian blue micromotor (PB MMs) were constructed by gas-shearing technology for efficient degradation of biofilms by combining chemodynamic therapy (CDT) and photothermal therapy (PTT). With the interpenetrating network crosslinked by alginate, chitosan (CS) and metal ions as the substrate, PB was generated and embedded in the micromotor at the same time of crosslinking. The micromotors are more stable and could capture bacteria with the addition of CS. The micromotors show excellent performance, containing photothermal conversion, reactive oxygen species (ROS) generation and bubble produced by catalyzing Fenton reaction for motion, which served as therapeutic agent could chemically kill bacteria and physically destroy biofilm. This research work opens a new path of an innovative strategy to efficiently remove biofilm.
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Quitosana , Alginatos , Biofilmes , FerrocianetosRESUMO
Rapid and broad diagnostic methods are needed for the identification of viral agents of gastroenteritis. In this study, we used Luminex xMAP technology to develop a multiplexed assay for the simultaneous identification of major enteric viral pathogens, including rotavirus A (RVA), noroviruses (NoVs) (including genogroups GI and GII), sapoviruses (SaV), human astrovirus (HAstV), enteric adenoviruses (EAds), and human bocavirus 2 (HBoV2). The analytical sensitivity allowed detection of 10(3) (EAds, HBoV2, and RVA) and 10(4) (NoV GI and GII, SaV, and HAstV) copies per reaction mixture. Compared to conventional PCR, the Luminex-based assay yielded greater than 75% sensitivity and 97% specificity for each virus, and the kappa correlation for detection of all viruses ranged from 0.75 to 1.00. In conclusion, this multiplexed Luminex-based assay provides a potentially rapid, high-throughput, and maneuverable diagnostic tool for major viral pathogens associated with gastroenteritis.
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Gastroenterite/diagnóstico , Técnicas de Diagnóstico Molecular/métodos , Reação em Cadeia da Polimerase Multiplex/métodos , Virologia/métodos , Viroses/diagnóstico , Vírus/isolamento & purificação , Criança , Pré-Escolar , Gastroenterite/virologia , Humanos , Sensibilidade e Especificidade , Fatores de Tempo , Viroses/virologia , Vírus/classificaçãoRESUMO
Using a high-throughput DNA sequencing method, one DNA sequence (contig01006), suspected to belong to a novel porcine bocavirus (PBoV), was found with a high rate of detection (19.6 %) in fecal samples from healthy piglets. Moreover, a novel PBoV (tentatively named PBoV3C) with a nearly complete genome sequence (5235 bp) was identified. PBoV3C exhibits typical genome characteristics of bocaviruses and shows the highest genomic sequence identity (78 % to 81 %) to PBoV3A/B (PBoV3/4-UK) and PBoV3D/E (PBoV3/4-HK), respectively. Phylogenetic and recombination analysis indicated high diversity, prevalence and complexity among the PBoVs. The phospholipase A2 (PLA2) site of VP1 and the secondary structure of VP2 of PBoV3C were also analyzed. Additionally, we propose a uniform method of PBoV nomenclature based on the VP1 gene.
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Bocavirus/genética , DNA Viral/química , DNA Viral/genética , Genoma Viral , Animais , Bocavirus/isolamento & purificação , Análise por Conglomerados , Dados de Sequência Molecular , Filogenia , Estrutura Secundária de Proteína , Análise de Sequência de DNA , Homologia de Sequência , Suínos , Terminologia como Assunto , Proteínas Virais/química , Proteínas Virais/genéticaRESUMO
Prussian blue (PB) with distinct hollow mesoporous structure and favorable properties has captured the attention of extensive biomaterial researchers. However, there is an unmet need for biocompatible PB microparticles with recyclability fabricated by a facile method. Herein, a size-controlled PB alginate microparticles (PBAMs) generated by a one-step and large batch production gas-shearing strategy. With the characteristic of porous and surface-modifiable, PBAMs used as vehicles may effectively load and release drug to improve the therapeutic efficacy. Meanwhile, Fe2+ in PBAMs exerts a catalyze for chemodynamic therapy (CDT) to produce reactive oxygen species (ROS), which synergizes with the photothermal therapy (PTT) induced by PB particles with effective photothermal conversion, achieving active tri-modality combination antitumor and antibacterial. The new concept for the low-cost and facile preparation of biocompatible PBAMs here illustrated opens a novel pathway toward the effective multifunctional platform.
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Alginatos , Nanopartículas , Antibacterianos/farmacologia , Ferrocianetos/química , Nanopartículas/química , Terapia FototérmicaRESUMO
Biocatalytic reaction networks in eukaryotic cells is realized by the immobilized and compartmental multi-enzymatic system. Inspired by the spatial localization of natural cells, multiple enzymes were confined within the multicompartmental microcapsules, which were created using a gas-shearing method coupled with surface-triggered in situ gelation strategy. Heterogeneous multicompartmental (two-, three-, four-, six-, or eight-faced) core particles, due to their capacity for positional assembly, were encapsuled in alginate hydrogel shells. The generated microcapsules integrate logic network to access complex digital design through a three-step convergent enzymatic cascade reaction as a model, and the capsules with high stability, recyclability and cytocompatibility are ideal enzymatic reactor systems to be used for biomimetic biocatalysis process.
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Alginatos , Hidrogéis , Biocatálise , Cápsulas , ÁguaRESUMO
Human bocavirus 2 (HBoV2) is a parvovirus that has been recently identified in stool samples from children. Any association between the virus and clinical disease is unclear. A rapid, reliable diagnostic method is necessary to address this issue. In this study, we developed a sensitive and specific HBoV2 quantitative real-time PCR assay that targets the HBoV2 NP-1 gene, based on the TaqMan method. The assay could reproducibly detect 10 copies of a recombinant DNA plasmid containing a partial region of the HBoV2 genome, with a dynamic range of 8 log units (10(1) to 10(8) copies). A clinical evaluation detected HBoV2 in 85 (24.6%) of 345 children with gastroenteritis, with viral loads ranging from 1.67 × 10(2) to 4.27 × 10(9) copies per ml of stool specimen.
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Técnicas de Laboratório Clínico/métodos , Bocavirus Humano/isolamento & purificação , Infecções por Parvoviridae/diagnóstico , Reação em Cadeia da Polimerase/métodos , Virologia/métodos , Pré-Escolar , Primers do DNA/genética , DNA Viral/química , DNA Viral/genética , Feminino , Bocavirus Humano/classificação , Bocavirus Humano/genética , Humanos , Lactente , Masculino , Dados de Sequência Molecular , Infecções por Parvoviridae/virologia , Sensibilidade e Especificidade , Análise de Sequência de DNARESUMO
BACKGROUND: Human bocavirus 2(HBoV2) and other human bocavirus species (HBoV, HBoV3, and HBoV4) have been discovered recently. But the precise phylogenetic relationships among these viruses are not clear yet. METHODS: We collected 632 diarrhea and 162 healthy children in Lanzhou, China. Using PCR, Human bocavirus (HBoV), HBoV2, HBoV3 and HBoV4 were screened. The partial genes of NS, NP1 and VP, and two nearly complete sequences of HBoV2 were obtained. RESULT: Phylogenetic analysis showed the different genes of HBoV2 strain were homogenous with different reference strains. HBoV3 may be a recombinant derived from HBoV and HBoV4. We also observed that the VP1 and VP2 region of HBoV3 is as similar to HBoV2 as to HBoV4. CONCLUSIONS: A single genetic lineage of HBoV2 is circulating in children with and without gastroenteritis in Lanzhou, China. Current evidence in this study was not enough to support recombination between HBoV2 strains, and HBoV3 may be a recombinant between HBoV and the common ancestor of HBoV2 and HBoV4.
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DNA Viral/genética , Evolução Molecular , Bocavirus Humano/genética , Bocavirus Humano/isolamento & purificação , Infecções por Parvoviridae/virologia , Filogenia , Recombinação Genética , Pré-Escolar , China , Análise por Conglomerados , Diarreia/virologia , Bocavirus Humano/classificação , Humanos , Lactente , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Proteínas Virais/genéticaRESUMO
Stool specimens were collected from 1,195 young children with acute diarrhea in Lanzhou, China, from 2001 to 2007. RT-PCR was used to detect human calicivirus (HucV). One hundred seventeen specimens were found positive for HucV. The infection rate was noticeably higher during 2006-2007 compared to the other years studied. Ninety-six specimens were sequenced to determine the genotypes of HucV. Eighty-six were norovirus and 10 were sapovirus, while GII/4 was the predominant strain of NV, followed by GII/3. The subtype of NV GII/4 changed from the Farmington Hills strain to the Bristol strain, and then to the Hunter strain and variant 2006b strain, over time. Variant 2006b has become the major epidemic strain in Lanzhou and should be closely monitored in the coming years.
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Infecções por Caliciviridae/epidemiologia , Infecções por Caliciviridae/virologia , Gastroenterite/epidemiologia , Gastroenterite/virologia , Norovirus/isolamento & purificação , Sapovirus/isolamento & purificação , Pré-Escolar , China/epidemiologia , Feminino , Genótipo , Humanos , Incidência , Lactente , Recém-Nascido , Masculino , Epidemiologia Molecular , Norovirus/genética , RNA Viral/genética , RNA Viral/isolamento & purificação , Sapovirus/genética , Análise de Sequência de DNARESUMO
BACKGROUND: Human bocavirus (HBoV) was recently discovered in children with respiratory tract disease and gastroenteritis. The causative role of HBoV in human gastroenteritis remains uncertain, and, to our knowledge, no previous case-control study has studied the relationship between HBoV and gastroenteritis. METHODS: We conducted a case-control study that examined stool samples from 397 children with diarrhea and from 115 asymptomatic control subjects. HBoV was detected using polymerase chain reaction. Real-time polymerase chain reaction was used to quantify the HBoV loads in case and control groups. Common enteric viruses were examined using enzyme-linked immunosorbent assays, polymerase chain reaction, and reverse-transcription polymerase chain reaction. RESULTS: At least 1 viral agent was discovered in 60.2% of cases. HBoV was detected in 14 samples, and 9 were coinfected with either rotavirus (7 of 14 samples) or human calicivirus (2 of 14). Many (8 [57.1%] of 14) of the HBoV infections occurred during September-December 2006. Most (12 [85.7%]) of the HBoV-infected children were 7-18 months of age. The percentage of children with HBoV infection did not differ significantly between case patients and control subjects (3.5% vs. 3.5%), and the statistical analysis did not support a correlation between HBoV infection and more-severe clinical symptoms. The viral load differences between the 2 groups were not statistically significant (P = .09, by log-normal Student's t test). In addition, the VP1/VP2 partial gene of HBoV from case patients and control subjects showed minimal sequence variation. CONCLUSIONS: A single genetic lineage of HBoV was revealed in persons in China. Despite its high prevalence in stool samples, our study does not support a causative role of HBoV in gastroenteritis.
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Bocavirus/isolamento & purificação , Diarreia/virologia , Gastroenterite/virologia , Infecções por Parvoviridae/diagnóstico , Bocavirus/genética , Estudos de Casos e Controles , Pré-Escolar , China/epidemiologia , DNA Viral/análise , Diarreia/diagnóstico , Ensaio de Imunoadsorção Enzimática , Fezes/virologia , Feminino , Gastroenterite/diagnóstico , Humanos , Lactente , Recém-Nascido , Masculino , Infecções por Parvoviridae/epidemiologia , Filogenia , Reação em Cadeia da Polimerase , Prevalência , Rotavirus/isolamento & purificação , Infecções por Rotavirus/diagnóstico , Infecções por Rotavirus/epidemiologia , Carga Viral , Proteínas Estruturais Virais/genéticaRESUMO
Noroviruses are an important cause of acute gastroenteritis. Increasing data showed that the GII-4 strains are predominant worldwide and new GII-4 variants emerge every 1-2 years causing major epidemics. Surveillance of gastroenteritis in hospitalized children under 5 years of age in China is described. Among 1,110 specimens, 114 (10.3%) were positive for noroviruses, which was higher than adenoviruses (7.6%), astroviruses (3.5%), and sapoviruses (0.9%) and only lower than group A rotaviruses (40.6%). Thirty-eight of the 114 positive norovirus cases were co-infected with other enteric viruses. Five norovirus genotypes (GI-2, GI-4, GII-3, GII-4, and GII-14) were detected, with GII-4/2006b the most predominant type (64.9%). The reported recombinant of GII-3 capsid and GII-4 polymerase described previously was also detected frequently and a recombinant of GII-14 capsid and GII-6 polymerase was found for the first time. This study suggests that continual surveillance focusing on strain variation and dynamic change is important for understanding the epidemiology and development of a strategy for disease control and prevention.
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Infecções por Caliciviridae/epidemiologia , Infecções por Caliciviridae/virologia , Gastroenterite/epidemiologia , Gastroenterite/virologia , Norovirus/genética , Norovirus/isolamento & purificação , Recombinação Genética , Pré-Escolar , China/epidemiologia , Genótipo , Humanos , Lactente , Recém-Nascido , Epidemiologia Molecular , Dados de Sequência Molecular , Filogenia , RNA Viral/genética , Análise de Sequência de DNA , Homologia de SequênciaRESUMO
BACKGROUND: Human bocavirus (HBoV) was first identified in children with acute respiratory-tract infections, but recent studies have revealed that HBoV is also frequently detected in fecal specimens from children with gastroenteritis. OBJECTIVES: To investigate the prevalence of HBoV in children hospitalized with gastroenteritis in different areas of China. STUDY DESIGN: Employing ELISA, RT-PCR or PCR, we evaluated 1216 fecal samples for common diarrheal agents from children aged less than 5-year-old hospitalized with acute gastroenteritis. MEGA software was used to construct phylogenetic trees of the VP1/VP2 partial sequences of the HBoV genome. RESULTS: There were 67 HBoV-positive specimens, 52 (77.6%) were co-infected with rotavirus, norovirus, astrovirus, or enteric adenovirus. Statistical analysis of the clinical data indicated that children infected with both rotavirus and bocavirus did not have more severe clinical symptoms than children infected with rotavirus. The phylogenetic analysis of the VP1/VP2 partial sequences of the HBoV genome revealed a single genetic lineage. CONCLUSIONS: Despite its high infection rate, there was no statistically significant a causual relationship between HBoV and gastroenteritis in children.