Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 88.283
Filtrar
1.
Water Res ; 171: 115435, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31927096

RESUMO

Escherichia coli levels in recreational waters are often used to predict when fecal-associated pathogen levels are a human health risk. The reach of the Chattahoochee River that flows through the Chattahoochee River National Recreation Area (CRNRA), located in the Atlanta-metropolitan area, is a popular recreation area that frequently exceeds the U.S. Environmental Protection Agency beach action value (BAV) for E. coli. A BacteriALERT program has been implemented to provide real-time E. coli estimates in the reach and notify the public of potentially harmful levels of fecal-associated pathogens as indicated by surrogate models based on real-time turbidity measurements from continuous water quality monitoring stations. However, E. coli does not provide information about the sources of fecal contamination and its accuracy as a human health indicator is questionable when sources of contamination are non-human. The objectives of our study were to investigate, within the Park and surrounding watersheds, seasonal and precipitation-related patterns in microbial source tracking marker concentrations of possible sources (human, dog, and ruminant), assess correlations between source contamination levels and culturable E. coli levels, determine which sources best explained model-based E. coli estimates above the BAV and detection of esp2 (a marker for the esp gene associated with pathogenic strains of Enterococcus faecium and Enterococcus faecalis), and investigate associations between source contamination levels and land use features. Three BacteriALERT sites on the Chattahoochee River were sampled six times per season in the winter and summer from December 2015 through September 2017, and 11 additional stream sites (synoptic sites) from the CRNRA watershed were sampled once per season. Samples were screened with microbial source tracking (MST) quantitative PCR (qPCR) markers for humans (HF183 Taqman), dogs (DogBact), and ruminants (Rum2Bac), the esp2 qPCR marker, and culturable E. coli. At the BacteriALERT sites, HF183 Taqman concentrations were higher under wet conditions DogBact concentrations were greater in the winter and under wet conditions, and Rum2Bac concentrations were comparatively low throughout the study with no difference across seasons or precipitation conditions. Concentrations of HF183 Taqman, DogBact, and Rum2Bac were positively correlated with culturable E. coli concentrations; however, DogBact had the largest R2 value among the three markers, and the forward stepwise regression indicated it was the best predictor of culturable E. coli concentrations at the BacteriALERT sites. Recursive partitioning indicated that BAV exceedances of model-based E. coli estimates were best explained by DogBact concentrations ≥3 gene copies per mL (CN/mL). Detections of esp2 at BacteriALERT sites were best explained by DogBact concentrations ≥11 CN/mL, while detections of esp2 at synoptic sites were best explained by HF183 Taqman ≥29 CN/mL. At the synoptic sites, HF183 Taqman levels were associated with wastewater treatment plant density. However, this relationship was driven primarily by a single site, suggesting possible conveyance issues in that catchment. esp2 detections at synoptic sites were positively associated with development within a 2-km radius and negatively associated with development within the catchment, suggesting multiple sources of esp2 in the watershed. DogBact and Rum2Bac were not associated with the land use features included in our analyses. Implications for Park management include: 1) fecal contamination levels were highest during wet conditions and in the off season when fewer visitors are expected to be participating in water-based recreation, 2) dogs are likely contributors to fecal contamination in the CRNRA and may be sources of pathogenic bacteria indicating further investigation of the origins of this contamination may be warranted as would be research to understand the human health risks from exposure to dog fecal contamination, and 3) high levels of the human marker at one site in the CRNRA watershed suggests more extensive monitoring in that catchment may locate the origin of human fecal contamination detected during this study.


Assuntos
Escherichia coli , Rios , Animais , Cães , Monitoramento Ambiental , Fezes , Humanos , Recreação , Estações do Ano , Microbiologia da Água , Poluição da Água
2.
Zool Res ; 41(1): 20-31, 2020 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-31930784

RESUMO

There is a growing appreciation for the specific health benefits conferred by commensal microbiota on their hosts. Clinical microbiota analysis and animal studies in germ-free or antibiotic-treated mice have been crucial for improving our understanding of the role of the microbiome on the host mucosal surface; however, studies on the mechanisms involved in microbiome-host interactions remain limited to small animal models. Here, we demonstrated that rhesus monkeys under short-term broad-spectrum antibiotic treatment could be used as a model to study the gut mucosal host-microbiome niche and immune balance with steady health status. Results showed that the diversity and community structure of the gut commensal bacteria in rhesus monkeys were both disrupted after antibiotic treatment. Furthermore, the 16S rDNA amplicon sequencing results indicated that Escherichia-Shigella were predominant in stool samples 9 d of treatment, and the abundances of bacterial functional genes and predicted KEGG pathways were significantly changed. In addition to inducing aberrant morphology of small intestinal villi, the depletion of gut commensal bacteria led to increased proportions of CD3 + T, CD4 + T, and CD16 + NK cells in peripheral blood mononuclear cells (PBMCs), but decreased numbers of Treg and CD20 + B cells. The transcriptome of PBMCs from antibiotic-treated monkeys showed that the immune balance was affected by modulation of the expression of many functional genes, including IL-13, VCAM1, and LGR4.


Assuntos
Disbiose/imunologia , Microbioma Gastrointestinal , Intestinos/anatomia & histologia , Macaca mulatta/microbiologia , Animais , Antibacterianos/farmacologia , Bactérias/classificação , Bactérias/efeitos dos fármacos , Bactérias/genética , DNA Bacteriano/genética , Fezes/microbiologia , Intestinos/microbiologia , Masculino
4.
Bioresour Technol ; 301: 122757, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31978700

RESUMO

Various spectroscopic and electrochemical techniques combined was used to investigate the compositional changes of dissolved organic matter (DOM) and the difference in humification degree during full-scale cow dung vermicomposting. This study also investigated that whether the two techniques could be used as humification indices. The physicochemical characteristics of vermicompost were superior to those of the control, indicating that vermicomposting significantly accelerated the humification process, which was confirmed by spectroscopic and electrochemical analyses. Meanwhile, the changes of three components identified and electron transfer capacities in vermicomposting further revealed that vermicomposting resulted in significant compositional changes of DOM and higher humification degree. Partial least squares path modeling and redundancy analysis revealed that the two techniques could be used as humification indices for vermicomposting. These results of this study demonstrated that the combination of spectroscopy and electrochemistry was applicable to characterize the compositional changes of DOM and the humification degree of vermicomposting.


Assuntos
Esterco , Solo , Animais , Bovinos , Técnicas Eletroquímicas , Fezes , Feminino , Substâncias Húmicas , Espectrometria de Fluorescência
5.
J Zoo Wildl Med ; 50(4): 813-821, 2020 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-31926511

RESUMO

Accredited zoos and animal parks play an important role in animal health research and conservation, providing important insights on matters of public health including zoonotic infectious diseases and antimicrobial resistance (AMR). The emergence and spread of AMR is a complex phenomenon that jeopardizes human and animal health and also threatens the long-term survival of endangered species. The presence of ß-lactamases in clinical isolates is particularly significant as they can jeopardize the efficacy of critically important antimicrobials. Although the presence of ß-lactamases and extended-spectrum ß-lactamases (ESBLs) producing Enterobacteriaceae in zoo animals has been reported, data are not available for northern European countries. In addition, few data are available on phylogenetic grouping of Escherichia coli isolated from zoo animals that can provide additional information on the host-bacterium relationship and on the pathogenicity of isolates. This study aimed to characterize fecal E. coli isolated from 33 healthy zoo animals from 22 species in Ireland, using conventional and molecular microbiological methods. All E. coli isolates were ampicillin resistant, but combined resistance to amoxicillin and clavulanic acid was not detected. Three E. coli isolates sampled from one Amur tiger, one Bornean orangutan, and one Southern white rhino were multidrug resistant, and blaTEM was detected in E. coli recovered from the Amur tiger and the Bornean orangutan. Other ß-lactamases, including ESBLs and AmpCs and plasmid-mediated mcr-1 and mcr-2, were not detected. Overall, E. coli isolates investigated were susceptible to the majority of the antimicrobials tested, and only two animals shed E. coli carrying ß-lactamase-encoding genes. The majority of isolates belonged to phylogenetic group B1. The screening of the AMR phenotype and genotype of zoo animal E. coli provides useful data that is relevant to antimicrobial stewardship in the zoo veterinary services and relevant to the bank of knowledge needed for tackling AMR.


Assuntos
Animais de Zoológico , Escherichia coli/efeitos dos fármacos , Escherichia coli/isolamento & purificação , Fezes/microbiologia , Animais , Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Regulação Bacteriana da Expressão Gênica/fisiologia , Filogenia
6.
Water Res ; 171: 115440, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31955059

RESUMO

Managing waterborne and water-related diseases is one of the most critical factors in the aftermath of hurricane-induced natural disasters. The goal of the study was to identify water-quality impairments in order to set the priorities for post-hurricane relief and to guide future decisions on disaster preparation and relief administration. Field investigations were carried out on St. Thomas, U.S. Virgin Islands as soon as the disaster area became accessible after the back-to-back hurricane strikes by Irma and Maria in 2017. Water samples were collected from individual household rain cisterns, the coastal ocean, and street-surface runoffs for microbial concentration. The microbial community structure and the occurrence of potential human pathogens were investigated in samples using next generation sequencing. Loop mediated isothermal amplification was employed to detect fecal indicator bacteria, Enterococcus faecalis. The results showed both fecal indicator bacteria and Legionella genetic markers were prevalent but were low in concentration in the water samples. Among the 22 cistern samples, 86% were positive for Legionella and 82% for Escherichia-Shigella. Enterococcus faecalis was detected in over 68% of the rain cisterns and in 60% of the coastal waters (n = 20). Microbial community composition in coastal water samples was significantly different from cistern water and runoff water. Although identification at bacterial genus level is not direct evidence of human pathogens, our results suggest cistern water quality needs more organized attention for protection of human health, and that preparation and prevention measures should be taken before natural disasters strike.


Assuntos
Tempestades Ciclônicas , Qualidade da Água , Fezes , Humanos , Ilhas , Chuva , Ilhas Virgens Americanas , Microbiologia da Água
7.
Clin Sci (Lond) ; 134(2): 289-302, 2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-31961431

RESUMO

Preeclampsia (PE) is regarded as a pregnancy-associated hypertension disorder that is related to excessive inflammatory responses. Although the gut microbiota (GM) and short-chain fatty acids (SCFAs) have been related to hypertension, their effects on PE remain unknown. We determined the GM abundance and faecal SCFA levels by 16S ribosomal RNA (rRNA) sequencing and gas chromatography, respectively, using faecal samples from 27 patients with severe PE and 36 healthy, pregnant control subjects. We found that patients with PE had significantly decreased GM diversity and altered GM abundance. At the phylum level, patients with PE exhibited decreased abundance of Firmicutes albeit increased abundance of Proteobacteria; at the genus level, patients with PE had lower abundance of Blautia, Eubacterium_rectale, Eubacterium_hallii, Streptococcus, Bifidobacterium, Collinsella, Alistipes, and Subdoligranulum, albeit higher abundance of Enterobacter and Escherichia_Shigella. The faecal levels of butyric and valeric acids were significantly decreased in patients with PE and significantly correlated with the above-mentioned differential GM abundance. We predicted significantly increased abundance of the lipopolysaccharide (LPS)-synthesis pathway and significantly decreased abundance of the G protein-coupled receptor (GPCR) pathway in patients with PE, based on phylogenetic reconstruction of unobserved states (PICRUSt). Finally, we evaluated the effects of oral butyrate on LPS-induced hypertension in pregnant rats. We found that butyrate significantly reduced the blood pressure (BP) in these rats. In summary, we provide the first evidence linking GM dysbiosis and reduced faecal SCFA to PE and demonstrate that butyrate can directly regulate BP in vivo, suggesting its potential as a therapeutic agent for PE.


Assuntos
Ácidos Graxos Voláteis/análise , Microbioma Gastrointestinal/fisiologia , Hipertensão/fisiopatologia , Pré-Eclâmpsia/fisiopatologia , Adulto , Animais , Bactérias/classificação , Bactérias/genética , Pressão Sanguínea/efeitos dos fármacos , Pressão Sanguínea/fisiologia , Butiratos/administração & dosagem , Butiratos/análise , Butiratos/metabolismo , Ácidos Graxos Voláteis/metabolismo , Fezes/química , Fezes/microbiologia , Feminino , Microbioma Gastrointestinal/efeitos dos fármacos , Microbioma Gastrointestinal/genética , Humanos , Hipertensão/metabolismo , Hipertensão/microbiologia , Ácidos Pentanoicos/análise , Ácidos Pentanoicos/metabolismo , Dinâmica Populacional , Pré-Eclâmpsia/metabolismo , Pré-Eclâmpsia/microbiologia , Gravidez , RNA Ribossômico 16S/genética , Ratos Sprague-Dawley
8.
Bull Entomol Res ; 110(1): 106-114, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31190655

RESUMO

We investigated the effects of the antiparasitic drug ivermectin on the dung beetles Copris acutidens Motschulsky, Onthophagus bivertex Heyden, O. lenzii Harold and Phelotrupes auratus auratus Motschulsky in Japan. Ivermectin was detected in cattle dung from 1 to 3 or 7 days post-treatment, with a peak at 3 days post-treatment in two pour-on administrations (500 µg kg-1). In C. acutidens, adult survivals and numbers of brood balls were significantly reduced in dung collected at 3 and 7 days post-treatment, and adult emergence rates were significantly decreased in dung collected at 7 and 14 days post-treatment. Feeding activity of C. acutidens was inhibited in dung collected at 3 days post-treatment, but was not significantly different from that seen in control dung at 7 and 14 days post-treatment. In O. bivertex and O. lenzii, there were no effects of ivermectin on adult survival or feeding activities, but the numbers of brood balls of O. bivertex constructed in dung collected at 3 and 7 days post-treatment were significantly lower than observed with control dung. The adult emergence rates of O. bivertex and O. lenzii were significantly reduced in dung collected at 1 to 3 and 1 to 7 days post-treatment, respectively. In P. auratus, there were no effects of ivermectin on adult survival, oviposition, feeding activity, or larval survival (until the third instar) in dung at 3 days post-treatment. The environmental risks affecting the populations of dung beetles in Japan are discussed.


Assuntos
Antiparasitários/toxicidade , Besouros/efeitos dos fármacos , Ivermectina/toxicidade , Animais , Antiparasitários/análise , Fezes/química , Comportamento Alimentar/efeitos dos fármacos , Feminino , Ivermectina/análise , Masculino , Reprodução/efeitos dos fármacos , Testes de Toxicidade Subcrônica
9.
Water Res ; 170: 115334, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31794889

RESUMO

Echinococcus multilocularis is a parasite that causes a dangerous zoonosis, alveolar echinococcosis (AE). Its presence in water sources, however, has scarcely been studied heretofore. Accordingly, 222 samples of different origin including wastewater from wastewater treatment plants (WWTPs) (n = 137), slaughterhouse (n = 49) as well as water from rivers (n = 26) and a cattle farm (n = 10) were collected from Xining City and a rural area in Qinghai-Tibet Plateau (QTP), an endemic area. Material obtained after processing of 10 L volume samples was subsequently analysed using three molecular detection methods: nested PCR, real-time PCR and LAMP. E. multilocularis DNA was found in 13 (5.85%) water samples; including 8 (5.8%), 3 (6%), 2 (20%) and 0 positive samples found in WWTPs, a slaughterhouse, a cattle farm and rivers, respectively. All three (LAMP, PCR, RT-PCR) molecular tools displayed high agreement and effectiveness in their ability of detecting the parasite's DNA in environmental material. This is the first investigation describing E. multilocularis detection in wastewater samples, using three sensitive molecular diagnostic tools. Results indicate the role of wastewater in dissemination of E. multilocularis and the risk of contamination of water sources.


Assuntos
Água Potável , Echinococcus multilocularis , Animais , Bovinos , China , Fezes , Tibet , Águas Residuárias
10.
Water Res ; 170: 115294, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31765827

RESUMO

Recreational water epidemiology studies are rare in settings with minimal wastewater treatment where risk may be highest, and in tropical settings where warmer temperature influences the ecology of fecal indicator bacteria commonly used to monitor recreational waters. One exception is a 1999 study conducted in São Paulo Brazil. We compared the risk and exposure characteristics of these data with those conducted in the United Kingdom (UK) in the early 1990s that are the basis of the World Health Organization's (WHO) guidelines on recreational water risks. We then developed adjusted risk difference models (excess gastrointestinal illness per swimming event) for children (<10 years of age) and non-children (≥10 years of age) across five Brazil beaches. We used these models along with beach water quality data from 2004 to 2015 to assess spatial and temporal trends in water quality and human risk. Risk models indicate that children in Brazil have as much as two times the risk of gastrointestinal illness than non-children. In Brazil, 11.8% of the weekly water samples from 2004 to 2015 exceeded 158 enterococci CFU/100 ml, the highest level of fecal streptococci concentration measured in the UK study. Risks associated with these elevated levels equated to median NEEAR-Gastrointestinal Illness (NGI) risks of 53 and 96 excess cases per 1000 swimmers in non-children and children, respectively. Two of the five beaches appear to drive the overall elevated NGI risks seen during this study. Distinct enteric pathogen profiles that exist in tropical settings as well as in settings with minimal wastewater treatment highlight the importance of regionally specific guideline development.


Assuntos
Praias , Microbiologia da Água , Brasil , Criança , Clima , Monitoramento Ambiental , Fezes , Humanos , Reino Unido
11.
Life Sci ; 240: 117089, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31759038

RESUMO

AIMS: Gut microbiota has been closely linked to the mucosal immune and been regarded as a reliable target for intestinal inflammation. This study aimed to explore the therapeutic roles of probiotic mixtures of Bifidobacterium infantis, Lactobacillus acidophilus, Enterococcus faecalis with (quadruple probiotics, P-qua) or without (triple probiotics, P-tri) aerobic Bacillus cereus in colitis, focusing on the multiple barrier functions. MATERIALS AND METHODS: Chronic colitis was induced by dextran sulfate sodium (DSS) in C57BL/6 mice. The probiotic mixtures P-qua or P-tri was gavage administrated respectively, while fecal microbiota transplantation (FMT) as a positive control. The intestinal inflammation and functions of multiple barriers were assessed, including the mucus barrier, epithelial barrier and endothelial barrier known as gut-vascular barrier (GVB). Altered composition and diversity in gut microbiota were observed via sequencing analysis. KEY FINDINGS: Both P-qua and P-tri relieved the intestinal inflammation and improved the functions of multiple barriers with increased integrity of mucous layer, enhanced transepithelial electrical resistance, declined epithelial and endothelial permeability to macromolecules in DSS-colitis. Aerobe-contained P-qua revealed a more active role in barrier recovering relative to P-tri, while FMT as a positive control seemed to get better results than pure probiotics. Indeed, P-qua was effective in rebuilding the structure and diversity of gut flora in DSS-colitis, especially increased abundance of Bifidobacterium, Akkermansia, Lactobacillus and Bacteroides. SIGNIFICANCE: Aerobe-contained P-qua was a powerful adjuvant therapy for chronic colitis, via restoring the intestinal microflora and recovering the multi-barriers in the inflamed gut.


Assuntos
Bactérias Aeróbias , Colite/induzido quimicamente , Colite/tratamento farmacológico , Probióticos/uso terapêutico , Animais , Permeabilidade da Membrana Celular , Doença Crônica , Colite/patologia , Sulfato de Dextrana , Transplante de Microbiota Fecal , Fezes/microbiologia , Microbioma Gastrointestinal , Mucosa Intestinal/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Probióticos/administração & dosagem , Junções Íntimas
12.
Toxicol Lett ; 319: 225-236, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31760063

RESUMO

N-Butylbenzenesulfonamide (NBBS) is a plasticizer detected in the environment suggesting potential human exposure. These studies investigated the in vitro hepatic clearance and disposition of [14C]NBBS in rodents following a single gavage (2, 20 or 200 mg/kg) or intravenous (IV) administration (20 mg/kg). NBBS was cleared slower in hepatocytes from humans compared to rodents. [14C]NBBS was well-absorbed in male rats following gavage administration and excreted extensively in urine (70-76 %) and feces (11-15 %) 72 h following administration. Following a 20 mg/kg gavage dose in male rats, 25 % of the dose was excreted in bile by 24 h suggesting that observed fecal excretion was due to biliary excretion. The radioactivity was distributed to tissues with 14 % and 8 % of the administered dose remaining in tissues at 24 and 72 h, respectively. There was no apparent dose-dependent effect in disposition in male rats. Disposition patterns were similar in female rats (urine, 83 %; feces, 14 %) and male (urine, 69 %; feces, 11 %) and female (urine, 72 %; feces, 9 %) mice following gavage administration of 20 mg/kg. The disposition following IV administration was similar to that of gavage. Urinary radiochemical profiles were similar between doses, routes, species, and sexes. Among numerous metabolites identified, oxidative metabolites of NBBS predominated.


Assuntos
Hepatócitos/metabolismo , Plastificantes/farmacocinética , Sulfonamidas/farmacocinética , Administração Intravenosa , Animais , Bile/metabolismo , Células Cultivadas , Fezes/química , Feminino , Humanos , Intubação Gastrointestinal , Masculino , Camundongos , Camundongos Endogâmicos , Plastificantes/metabolismo , Plastificantes/toxicidade , Ratos , Ratos Sprague-Dawley , Sulfonamidas/administração & dosagem , Sulfonamidas/metabolismo , Distribuição Tecidual
13.
Toxicol Lett ; 319: 31-39, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31707105

RESUMO

The bioabsorption and biotoxicity of cadmium are closely related to its binding form. Currently, total concentration is used as the indicator for evaluating cadmium toxicity in food, but it might not accurately reflect cadmium's toxic effects. This study attempted to evaluate the toxicity of the different forms of cadmium including cadmium-malate, cadmium-glutathione, and cadmium-metallothionein that are commonly found in food. The in vitro physiologically based extraction test (PBET) combined with Visual MINTEQ modeling was used to predict the toxicity of different forms of cadmium, and acute toxicity testing was performed in mice for validating their results. The in vivo experimental results showed that different forms of cadmium had diverse biotoxicities of which PBET was a good predictor. In particular, the simulation of cadmium ions in PBET using the MINTEQ software revealed that the free cadmium ion content in the simulated intestinal fluid had a superior linear relationship than the total cadmium concentration with the toxicology indexes. Verification using the other two forms of cadmium confirmed the accuracy of the prediction of their biotoxicity. These findings hopefully provide an important reference for a more accurate and rapid safety assessment of cadmium in food.


Assuntos
Compostos de Cádmio/farmacocinética , Compostos de Cádmio/toxicidade , Análise de Alimentos , Animais , Disponibilidade Biológica , Cádmio/análise , Simulação por Computador , Fezes/química , Contaminação de Alimentos , Absorção Intestinal , Masculino , Camundongos , Camundongos Endogâmicos ICR , Valor Preditivo dos Testes , Software , Distribuição Tecidual
14.
Arch Virol ; 165(1): 137-143, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31745718

RESUMO

Canine circovirus (canine CV) is an etiological agent associated with diarrhea, hemorrhagic gastroenteritis and vasculitis. Although canine CV has been identified and characterized in southern China in recent years, its epidemiology in other regions of China and its precise molecular characteristics have not been examined. In this study, we examined 141 fecal specimens collected from domestic dogs with or without diarrhea in Heilongjiang province, Northeastern China, during 2014 to 2016. A total of 18 out of 141 samples were found to be positive for canine CV by real-time quantitative PCR. In the diarrhea samples, canine CV was detected in coinfections with canine parvovirus 2. More importantly, two different canine CV strains were detected in one sample. Five canine CV genomes were successfully amplified. Sequence analysis showed that there were two unique amino acid changes in the Rep protein (N39S in the K1 strain, and T71A in the XF16 strain). Phylogenetic analysis indicated that canine CV could be divided into four genotypes, and specific nucleotide mutations could be used for confirming the four genotypes. Moreover, recombination analysis revealed that a total of eight recombination events were found in five genomic sequences. Molecular evolution analysis showed that the canine CV has been under purifying selection. This study provides evidence that at least three genotypes of canine CV are co-circulating in China. Continuous epidemiological surveillance is therefore necessary to understand their importance for the evolution of canine CV.


Assuntos
Circovirus/classificação , Diarreia/veterinária , Doenças do Cão/virologia , Mutação , Parvovirus Canino/isolamento & purificação , Animais , China , Circovirus/genética , Diarreia/virologia , Cães , Evolução Molecular , Fezes/virologia , Parvovirus Canino/genética , Filogenia , Proteínas Virais/genética , Sequenciamento Completo do Genoma
15.
Water Environ Res ; 92(1): 35-41, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31433097

RESUMO

Pinpointing water pollution sources using host-specific gastrointestinal microbes, known as microbial source tracking (MST), have significant benefits for countries with water quality management issues related to pollution. A recently discovered bacteriophage, crAssphage, shows promise as a human-specific MST marker. However, loss of genetic materials during the recovery and the detection processes could alter the ability to measure virus quantities in a water sample. This study determined the crAssphage recovery efficiencies in water sources, including seawater, freshwater, and influent and effluent from a wastewater treatment plant, by spiking natural crAssphage concentrates prior to DNA extraction and quantitative PCR analysis. The results showed that river and seawater with no or low crAssphage background experienced no recovery loss. Evaluating recovery efficiencies in samples with high crAssphage backgrounds posed a challenge due to the inability to prepare high crAssphage titers. This study highlights the importance of intra-laboratory assessment of recovery efficiency in environmental samples for retrieving absolute crAssphage quantification with correction of bias among water samples and increase in data accuracy. PRACTITIONER POINTS: In laboratory assessment of recovery efficiency is crucial for bias correction and data accuracy for absolute crAssphage quantification in water samples. No loss in crAssphage recovery was observed in river and seawater that contained no or low crAssphage backgrounds. Inability to prepare high crAssphage spike concentrations remains the major limitation for evaluating recovery in samples with high crAssphage backgrounds. The results underline the importance of evaluating method recovery in real environmental samples that reflect actual matrix effect. Absolute crAssphage quantification, as human-specific pollution marker, could be used for prioritizing water quality restoration and area-based management plan.


Assuntos
Esgotos , Água , Monitoramento Ambiental , Fezes , Humanos , Concentração de Íons de Hidrogênio , Microbiologia da Água , Poluição da Água
16.
Water Res ; 170: 115349, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31830650

RESUMO

Levels of fecal indicator bacteria (FIB) provide a surrogate measure of the microbial quality of water used for a wide range of applications. Despite the common use of these measures, a significant limitation is a delay in results due to the time required for cultivation and enumeration of FIB. Testing requires at least 18-24 h, and therefore, FIB cannot be used to identify current or real-time microbial water quality. An approach of nowcasting or empirical modelling approaches that incorporate water quality, environmental, and weather variables to predict FIB levels in real-time has been developed with some success. However, FIB levels are dependent on a complex interaction of numerous variables, which can be challenging to model with ordinary linear regression or classification methods most commonly applied. In this study, novel use of Bayesian Belief Networks (BBNs) that allow for a probabilistic representation of complex variable interactions is investigated for real-time modelling of FIB levels surface waters. In particular, the integration of both water quality measures and current/historical weather for prediction of fecal coliforms and Escherichia coli levels is achieved using BBNs. For 4-bin classification of fecal coliform levels, BBNs increased prediction accuracy by 25%-54% compared to other previously used techniques including logistic regression, Naïve Bayes, and random forests. Binary prediction of E. coli levels exceeding a threshold of 20 CFU/100 mL was also significantly improved using BBNs with prediction accuracies >90% for all monitoring sites. Advantages of the BBN approach are also demonstrated identifying the ability to make predictions from incomplete monitoring data as well as probabilistic inference of variable importance in FIB levels. In particular, the results indicate that water quality surrogates such as conductivity are essential to real-time prediction of FIB. The results and models described in this work can be readily utilized to provide accurate and real-time assessments of FIB levels in surface waters utilizing commonly monitored parameters.


Assuntos
Escherichia coli , Qualidade da Água , Teorema de Bayes , Monitoramento Ambiental , Fezes , Microbiologia da Água , Tempo (Meteorologia)
17.
J Agric Food Chem ; 68(1): 409-417, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31833363

RESUMO

Naringin has been documented to possess various bioactivities. Due to thorny endogenous interferences, the metabolism pathways of naringin and exact amounts of derived phenolic catabolites have not been definitely assigned. In this work, stable isotope-labeling-based liquid chromatography-mass spectrometry methods were developed to eliminate the endogenous interferences. [2',3',5',6'-D4]-naringin was orally administrated to rats. Urine and feces samples were collected and then analyzed with ultrahigh-performance liquid chromatography-quadrupole-time-of-flight tandem mass spectrometry (UHPLC-Q-TOF-MS/MS). A total of 21 flavonoid metabolites and 11 phenolic catabolites were screened. The metabolism and catabolism pathways were proposed. Furthermore, deuterated naringin and its main metabolites were determined with rapid resolution liquid chromatography tandem triple quadrupole mass spectrometry (RRLC-QqQ-MS/MS). The overall recovery of ingested deuterated naringin was calculated as 56.9% without endogenous interferences. The obtained results provide essential information for further pharmacological studies of naringin.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/química , Fezes/química , Flavanonas/química , Flavanonas/metabolismo , Marcação por Isótopo/métodos , Espectrometria de Massas/métodos , Animais , Medicamentos de Ervas Chinesas/metabolismo , Feminino , Flavanonas/urina , Masculino , Ratos , Ratos Sprague-Dawley
18.
Scand J Immunol ; 91(1): e12805, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31267543

RESUMO

Wiskott-Aldrich syndrome (WAS) is an X-linked primary immunodeficiency disease caused by a mutation in the WAS gene that encodes the WAS protein (WASp); up to 5-10% of these patients develop inflammatory bowel disease (IBD). The mechanisms by which WASp deficiency causes IBD are unclear. Intestinal microbial dysbiosis and imbalances in host immune responses play important roles in the pathogenesis of polygenetic IBD; however, few studies have conducted detailed examination of the microbial alterations and their relationship with IBD in WAS. Here, we collected faecal samples from 19 children (all less than 2 years old) with WAS and samples from WASp-KO mice with IBD and subjected them to 16S ribosomal RNA sequencing. We found that microbial community richness and structure in WAS children were different from those in controls; WAS children revealed reduced microbial community richness and diversity. Relative abundance of Bacteroidetes and Verrucomicrobiain in WAS children was significantly lower, while that of Proteobacteria was markedly higher. WASp-KO mice revealed a significantly decreased abundance of Firmicutes. Faecal microbial dysbiosis caused by WASp deficiency is similar to that observed for polygenetic IBD, suggesting that WASp may play crucial function in microbial homoeostasis and that microbial dysbiosis may contribute to IBD in WAS. These microbial alterations may be useful targets for monitoring and therapeutically managing intestinal inflammation in WAS.


Assuntos
Disbiose , Fezes/microbiologia , Microbioma Gastrointestinal , Síndrome de Wiskott-Aldrich/etiologia , Animais , Biodiversidade , Biomarcadores , Estudos de Casos e Controles , Pré-Escolar , Modelos Animais de Doenças , Feminino , Humanos , Lactente , Doenças Inflamatórias Intestinais/etiologia , Masculino , Metagenoma , Metagenômica/métodos , Camundongos , Camundongos Knockout , Mutação , RNA Ribossômico 16S/genética , Síndrome de Wiskott-Aldrich/diagnóstico , Proteína da Síndrome de Wiskott-Aldrich/deficiência
19.
Gut ; 69(1): 62-73, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-30923071

RESUMO

OBJECTIVE: The intestinal lumen contains several proteases. Our aim was to determine the role of faecal proteases in mediating barrier dysfunction and symptoms in IBS. DESIGN: 39 patients with IBS and 25 healthy volunteers completed questionnaires, assessments of in vivo permeability, ex vivo colonic barrier function in Ussing chambers, tight junction (TJ) proteins, ultrastructural morphology and 16 s sequencing of faecal microbiota rRNA. A casein-based assay was used to measure proteolytic activity (PA) in faecal supernatants (FSNs). Colonic barrier function was determined in mice (ex-germ free) humanised with microbial communities associated with different human PA states. RESULTS: Patients with IBS had higher faecal PA than healthy volunteers. 8/20 postinfection IBS (PI-IBS) and 3/19 constipation- predominant IBS had high PA (>95th percentile). High-PA patients had more and looser bowel movements, greater symptom severity and higher in vivo and ex vivo colonic permeability. High-PA FSNs increased paracellular permeability, decreased occludin and increased phosphorylated myosin light chain (pMLC) expression. Serine but not cysteine protease inhibitor significantly blocked high-PA FSN effects on barrier. The effects on barrier were diminished by pharmacological or siRNA inhibition of protease activated receptor-2 (PAR-2). Patients with high-PA IBS had lower occludin expression, wider TJs on biopsies and reduced microbial diversity than patients with low PA. Mice humanised with high-PA IBS microbiota had greater in vivo permeability than those with low-PA microbiota. CONCLUSION: A subset of patients with IBS, especially in PI-IBS, has substantially high faecal PA, greater symptoms, impaired barrier and reduced microbial diversity. Commensal microbiota affects luminal PA that can influence host barrier function.


Assuntos
Síndrome do Intestino Irritável/fisiopatologia , Serina Proteases/fisiologia , Adulto , Animais , Biópsia , Células CACO-2 , Estudos de Casos e Controles , Colo/patologia , Disbiose/enzimologia , Fezes/enzimologia , Feminino , Microbioma Gastrointestinal , Humanos , Absorção Intestinal/fisiologia , Mucosa Intestinal/metabolismo , Síndrome do Intestino Irritável/enzimologia , Síndrome do Intestino Irritável/microbiologia , Síndrome do Intestino Irritável/patologia , Masculino , Camundongos , Pessoa de Meia-Idade , Permeabilidade , Estudos Prospectivos , Proteólise , Índice de Gravidade de Doença , Proteínas de Junções Íntimas/metabolismo
20.
Gut ; 69(1): 42-51, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31036757

RESUMO

BACKGROUND AND AIMS: Prenatal and early life bacterial colonisation is thought to play a major role in shaping the immune system. Furthermore, accumulating evidence links early life exposures to the risk of developing IBD later in life. We aimed to assess the effect of maternal IBD on the composition of the microbiome during pregnancy and on the offspring's microbiome. METHODS: We prospectively examined the diversity and taxonomy of the microbiome of pregnant women with and without IBD and their babies at multiple time points. We evaluated the role of maternal IBD diagnosis, the mode of delivery, antibiotic use and feeding behaviour on the microbiome composition during early life. To assess the effects of IBD-associated maternal and infant microbiota on the enteric immune system, we inoculated germ-free mice (GFM) with the respective stool and profiled adaptive and innate immune cell populations in the murine intestines. RESULTS: Pregnant women with IBD and their offspring presented with lower bacterial diversity and altered bacterial composition compared with control women and their babies. Maternal IBD was the main predictor of the microbiota diversity in the infant gut at 7, 14, 30, 60 and 90 days of life. Babies born to mothers with IBD demonstrated enrichment in Gammaproteobacteria and depletion in Bifidobacteria. Finally, GFM inoculated with third trimester IBD mother and 90-day infant stools showed significantly reduced microbial diversity and fewer class-switched memory B cells and regulatory T cells in the colon. CONCLUSION: Aberrant gut microbiota composition persists during pregnancy with IBD and alters the bacterial diversity and abundance in the infant stool. The dysbiotic microbiota triggered abnormal imprinting of the intestinal immune system in GFM.


Assuntos
Microbioma Gastrointestinal/imunologia , Doenças Inflamatórias Intestinais/microbiologia , Complicações na Gravidez/microbiologia , Efeitos Tardios da Exposição Pré-Natal/microbiologia , Imunidade Adaptativa , Adulto , Animais , Bactérias/classificação , Bactérias/isolamento & purificação , Disbiose/imunologia , Disbiose/microbiologia , Transplante de Microbiota Fecal/métodos , Fezes/microbiologia , Feminino , Seguimentos , Trato Gastrointestinal/imunologia , Trato Gastrointestinal/microbiologia , Vida Livre de Germes , Humanos , Recém-Nascido , Doenças Inflamatórias Intestinais/imunologia , Masculino , Troca Materno-Fetal , Gravidez , Complicações na Gravidez/imunologia , Efeitos Tardios da Exposição Pré-Natal/imunologia , Estudos Prospectivos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA