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1.
Artículo en Inglés | MEDLINE | ID: mdl-36748601

RESUMEN

A novel anaerobic, mesophilic, non-spore-forming bacterium (strain m25T) was isolated from methanogenic enrichment cultures obtained from a lab-scale methanogenic landfill bioreactor containing anaerobic digester sludge. Cells were Gram-stain-negative, catalase-positive, oxidase-negative, rod-shaped, and motile by means of a flagellum. The genomic DNA G+C content was 40.11 mol%. The optimal NaCl concentration, temperature and pH for growth were 2.5 g l-1, 35 °C and at pH 7.0, respectively. Strain m25T was able to grow in the absence of yeast extract on glycerol, pyruvate, arginine and cysteine. In the presence of 0.2 % yeast extract, strain m25T grew on carbohydrates and was able to use glucose, cellobiose, fructose, raffinose and galactose. The novel strain could utilize glycerol, urea, pyruvate, peptone and tryptone. The major fatty acids were iso-C15  :  0, C14  :  0, C16  :  0 DMA (dimethyl acetal) and iso-C15 : 0 DMA. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the new isolate was closely related to Lutispora thermophila EBR46T (95.02 % 16S rRNA gene sequence similarity). Genome relatedness was determined using both average nucleotide identity and amino acid identity analyses, the results of which both strongly supported that strain m25T belongs to the genus Lutispora. Based on its unique phylogenetic features, strain m25T is considered to represent a novel species within the genus Lutispora. Moreover, based on its unique physiologic features, mainly the lack of spore formation, a proposal to amend the genus Lutispora is also provided to include the non-spore-forming and mesophilic species. Lutispora saccharofermentans sp. nov. is proposed. The type strain of the species is m25T (=DSM 112749T=ATCC TSD-268T).


Asunto(s)
ADN Bacteriano , Lactobacillales , Aguas del Alcantarillado/microbiología , Ácidos Grasos/química , Anaerobiosis , Filogenia , ARN Ribosómico 16S/genética , Glicerol , ADN Bacteriano/genética , Composición de Base , Técnicas de Tipificación Bacteriana , Análisis de Secuencia de ADN , Reactores Biológicos/microbiología , Bacterias Anaerobias/genética , Lactobacillales/genética , Clostridiaceae/genética , Piruvatos
2.
Proc Biol Sci ; 287(1941): 20202886, 2020 12 23.
Artículo en Inglés | MEDLINE | ID: mdl-33352082

RESUMEN

A fundamental aim of microbiome research is to understand the factors that influence the assembly and stability of host-associated microbiomes, and their impact on host phenotype, ecology and evolution. However, ecological and evolutionary theories applied to predict microbiome community dynamics are largely based on macroorganisms and lack microbiome-centric hypotheses that account for unique features of the microbiome. This special feature sets out to drive advancements in the application of eco-evolutionary theory to microbiome community dynamics through the development of microbiome-specific theoretical and conceptual frameworks across plant, human and non-human animal systems. The feature comprises 11 research and review articles that address: (i) the effects of the microbiome on host phenotype, ecology and evolution; (ii) the application and development of ecological and evolutionary theories to investigate microbiome assembly, diversity and stability across broad taxonomic scales; and (iii) general principles that underlie microbiome diversity and dynamics. This cross-disciplinary synthesis of theoretical, conceptual, methodological and analytical approaches to characterizing host-microbiome ecology and evolution across systems addresses key research gaps in the field of microbiome research and highlights future research priorities.


Asunto(s)
Evolución Biológica , Ecología , Microbiota , Animales , Humanos , Plantas
3.
Proc Biol Sci ; 287(1933): 20200956, 2020 08 26.
Artículo en Inglés | MEDLINE | ID: mdl-32811286

RESUMEN

Forest declines caused by climate disturbance, insect pests and microbial pathogens threaten the global landscape, and tree diseases are increasingly attributed to the emergent properties of complex ecological interactions between the host, microbiota and insects. To address this hypothesis, we combined reductionist approaches (single and polyspecies bacterial cultures) with emergentist approaches (bacterial inoculations in an oak infection model with the addition of insect larvae) to unravel the gene expression landscape and symptom severity of host-microbiota-insect interactions in the acute oak decline (AOD) pathosystem. AOD is a complex decline disease characterized by predisposing abiotic factors, inner bark lesions driven by a bacterial pathobiome, and larval galleries of the bark-boring beetle Agrilus biguttatus. We identified expression of key pathogenicity genes in Brenneria goodwinii, the dominant member of the AOD pathobiome, tissue-specific gene expression profiles, cooperation with other bacterial pathobiome members in sugar catabolism, and demonstrated amplification of pathogenic gene expression in the presence of Agrilus larvae. This study highlights the emergent properties of complex host-pathobiota-insect interactions that underlie the pathology of diseases that threaten global forest biomes.


Asunto(s)
Gammaproteobacteria , Interacciones Microbiota-Huesped , Enfermedades de las Plantas/microbiología , Árboles/microbiología , Animales , Escarabajos , Microbiota , Quercus/microbiología
4.
Blood ; 132(1): 59-66, 2018 07 05.
Artículo en Inglés | MEDLINE | ID: mdl-29784643

RESUMEN

Spatial intratumor heterogeneity is frequently seen in multiple myeloma (MM) and poses a significant challenge for risk classifiers, which rely on tumor samples from the iliac crest. Because biopsy-based assessment of multiple skeletal sites is difficult, alternative strategies for risk stratification are required. Recently, the size of focal lesions (FLs) was shown to be a surrogate marker for spatial heterogeneity, suggesting that data from medical imaging could be used to improve risk stratification approaches. Here, we investigated the prognostic value of FL size in 404 transplant-eligible, newly diagnosed MM patients. Using diffusion-weighted magnetic resonance imaging with background suppression, we identified the presence of multiple large FLs as a strong prognostic factor. Patients with at least 3 large FLs with a product of the perpendicular diameters >5 cm2 were associated with poor progression-free survival (PFS) and overall survival (OS; median, 2.3 and 3.6 years, respectively). This pattern, seen in 13.8% of patients, was independent of the Revised International Staging System (RISS), gene expression profiling (GEP)-based risk score, gain(1q), or extramedullary disease (hazard ratio, 2.7 and 2.2 for PFS and OS in multivariate analysis, respectively). The number of FLs lost its negative impact on outcome after adjusting for FL size. In conclusion, the presence of at least 3 large FL is a feature of high risk, which can be used to refine the diagnosis of this type of disease behavior and as an entry criterion for risk-stratified trials.


Asunto(s)
Imagen de Difusión por Resonancia Magnética , Mieloma Múltiple/diagnóstico por imagen , Mieloma Múltiple/mortalidad , Adulto , Supervivencia sin Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Medición de Riesgo , Factores de Riesgo , Tasa de Supervivencia
5.
Blood ; 130(1): 30-34, 2017 07 06.
Artículo en Inglés | MEDLINE | ID: mdl-28432222

RESUMEN

18F-Fluorodeoxyglucose (FDG)-positron emission tomography (PET) and diffusion-weighted magnetic resonance imaging with background signal suppression (DWIBS) are 2 powerful functional imaging modalities in the evaluation of malignant plasma cell (PC) disease multiple myeloma (MM). Preliminary observations have suggested that MM patients with extensive disease according to DWIBS may be reported as being disease-free on FDG-PET ("PET false-negative"). The aim of this study was to describe the proportion of PET false-negativity in a representative set of 227 newly diagnosed MM patients with simultaneous assessment of FDG-PET and DWIBS, and to identify tumor-intrinsic features associated with this pattern. We found the incidence of PET false-negativity to be 11%. Neither tumor load-associated parameters, such as degree of bone marrow PC infiltration, nor the PC proliferation rate were associated with this subset. However, the gene coding for hexokinase-2, which catalyzes the first step of glycolysis, was significantly lower expressed in PET false-negative cases (5.3-fold change, P < .001) which provides a mechanistic explanation for this feature. In conclusion, we demonstrate a relevant number of patients with FDG-PET false-negative MM and a strong association between hexokinase-2 expression and this negativity: a finding which may also be relevant for clinical imaging of other hematological cancers.


Asunto(s)
Fluorodesoxiglucosa F18/administración & dosificación , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Hexoquinasa/biosíntesis , Mieloma Múltiple , Proteínas de Neoplasias/biosíntesis , Tomografía de Emisión de Positrones , Reacciones Falso Positivas , Femenino , Humanos , Masculino , Mieloma Múltiple/diagnóstico por imagen , Mieloma Múltiple/enzimología
6.
Haematologica ; 103(6): 1047-1053, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29567784

RESUMEN

Fluorine-18 fluorodeoxyglucose positron emission tomography with computed tomography attenuation correction (PET-CT) in myeloma can detect and enumerate focal lesions by the quantitative characterization of metabolic activity. The aim of this study was to determine the prognostic significance of the suppression of PET-CT activity at a number of time points post therapy initiation: day 7, post induction, post transplant, and at maintenance therapy. As part of the TT4-6 trial series, 596 patients underwent baseline PET-CT and were evaluated serially during their disease course using peak standardized uptake values above background red marrow signal. We demonstrate that the presence of more than 3 focal lesions at presentation identifies a group of patients with an adverse progression-free survival and overall survival. At day 7 of therapy, patients with complete focal lesion signal suppression revert to the same prognosis as those with no lesions at diagnosis. At later time points, the continued suppression of signal remains prognostically important. We conclude that for newly diagnosed patients with focal lesions, treatment until these lesions are suppressed is an important therapeutic goal as the prognosis of these patients is the same as those without lesions at diagnosis. (clinicaltrials.gov identifiers: 00734877, 02128230, 00869232, 00871013).


Asunto(s)
Mieloma Múltiple/diagnóstico , Tomografía Computarizada por Tomografía de Emisión de Positrones , Anciano , Anciano de 80 o más Años , Terapia Combinada , Femenino , Fluorodesoxiglucosa F18 , Humanos , Masculino , Persona de Mediana Edad , Mieloma Múltiple/mortalidad , Mieloma Múltiple/terapia , Neoplasia Residual/diagnóstico , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Pronóstico , Análisis de Supervivencia , Resultado del Tratamiento
7.
J Ark Med Soc ; 111(2): 38-9, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25174156

RESUMEN

The pool of qualified nuclear medicine (NM) physicians is declining as fewer choose to enter the specialty. In June 2012, we began developing an integrated categorical residency training position satisfying the requirements of both the American Board of Radiology (ABR) and the American Board of Nuclear Medicine (ABNM). Termed "NuRad," this was listed and filled in the 2013 NRMP match. We found it to be more attractive to qualified applicants than our traditional, three year NM residency. This approach may play a significant role in the future in ensuring the training of physicians expert in NM and molecular imaging.


Asunto(s)
Certificación/organización & administración , Internado y Residencia/métodos , Medicina Nuclear/educación , Radiología/educación , Arkansas , Humanos , Medicina Nuclear/normas , Radiología/normas
8.
Environ Sci Technol ; 47(10): 5267-75, 2013 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-23590844

RESUMEN

Options for the storage and disposal of animal carcasses are extremely limited in the EU after the introduction of the EU Animal By-products Regulations (ABPR; EC/1774/2002), leading to animosity within the livestock sector and the call for alternative methods to be validated. Novel storage technologies such as bioreduction may be approved under the ABPR provided that they can be shown to prevent pathogen proliferation. We studied the survival of Enterococcus faecalis, Salmonella spp., E. coli O157 and porcine parvovirus in bioreduction vessels containing sheep carcasses for approximately 4 months. The vessels were operated under two different scenarios: (A) where the water within was aerated and heated to 40 °C, and (B) with no aeration or heating, to simulate vessel failure. Microbial analysis verified that pathogens were contained within the bioreduction vessel and indeed reduced in numbers with time under both scenarios. This study shows that bioreduction can provide an effective and safe on-farm storage system for livestock carcasses prior to ultimate disposal. The findings support a review of the current regulatory framework so that bioreduction is considered for approval for industry use within the EU.


Asunto(s)
Biodegradación Ambiental , Enterococcus faecalis/metabolismo , Escherichia coli O157/metabolismo , Salmonella/metabolismo , Animales , Secuencia de Bases , Cartilla de ADN , Enterococcus faecalis/genética , Escherichia coli O157/genética , ARN Ribosómico 16S/genética , Salmonella/genética , Ovinos
9.
Psychol Serv ; 20(2): 283-290, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36395059

RESUMEN

In 2020, the COVID-19 pandemic, the murder of George Floyd as well as other Black Americans, waves of violence against Asian American communities, and the 2020 presidential election created a national climate in the United States that almost defies description with regard to historical significance, collective emotional pain, and the urgency of the resulting calls for justice-focused action. This article explores the experience of three White psychologists/psychologists-in-training within this national context, and specifically, the impact on psychology training and supervision in the wake of the Executive Order on Combatting Race and Sex Stereotyping released in September 2020. Consistent with the extant literature in our field, we understand supervision to be an essential space for in-depth attention to trainee development around cultural humility and critical consciousness wherein we as supervisors also grow and deepen our own practice (Falender et al., 2013; Hook et al., 2016). As we navigated 2020, we found several key supervision processes particularly salient, including antiracism in supervision as mindful practice, facilitating learning while doing our own learning, supervisor consultation, and recognizing the impact of privilege on these processes. (PsycInfo Database Record (c) 2023 APA, all rights reserved).


Asunto(s)
COVID-19 , Veteranos , Humanos , Estados Unidos , Pandemias , Atención a la Salud
10.
Environ Microbiol ; 14(4): 1077-87, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22225785

RESUMEN

Cellulose is reputedly the most abundant organic polymer in the biosphere, yet despite the fundamental role of cellulolytic microorganisms in global carbon cycling and as potential sources of novel enzymes for biotechnology, their identity and ecology is not well established. Cellulose is a major component of landfill waste and its degradation is therefore a key feature of the anaerobic microbial decomposition process. Here, we targeted a number of taxa containing known cellulolytic anaerobes (members of the bacterial genus Fibrobacter, lineages of Clostridium clusters I, III, IV and XIV, and anaerobic fungi of the Neocallimastigales) in landfill leachate and colonized cellulose 'baits' via PCR and quantitative PCR (qPCR). Fibrobacter spp. and Clostridium clusters III, IV and XIV were detected in almost all leachate samples and cluster III and XIV clostridia were the most abundant (1-6% and 1-17% of total bacterial 16S rRNA gene copies respectively). Two landfill leachate microcosms were constructed to specifically assess those microbial communities that colonize and degrade cellulose substrates in situ. Scanning electron microscopy (SEM) of colonized cotton revealed extensive cellulose degradation in one microcosm, and Fibrobacter spp. and Clostridium cluster III represented 29% and 17%, respectively, of total bacterial 16S rRNA gene copies in the biofilm. Visible cellulose degradation was not observed in the second microcosm, and this correlated with negligible relative abundances of Clostridium cluster III and Fibrobacter spp. (≤ 0.1%), providing the first evidence that the novel fibrobacters recently detected in landfill sites and other non-gut environments colonize and degrade cellulose substrates in situ.


Asunto(s)
Celulosa/metabolismo , Fibrobacter/fisiología , Eliminación de Residuos , Bacterias Anaerobias/genética , Bacterias Anaerobias/metabolismo , Biodegradación Ambiental , Celulosa/análisis , Clostridium/genética , Clostridium/metabolismo , Cartilla de ADN/genética , Cartilla de ADN/metabolismo , Ecología , Fibrobacter/genética , Fibrobacter/metabolismo , Hongos/metabolismo , Reacción en Cadena de la Polimerasa , ARN Ribosómico 16S , Residuos/estadística & datos numéricos
11.
Appl Environ Microbiol ; 78(9): 3495-9, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22389367

RESUMEN

The relative abundance of micromonosporas in the bacterial communities inhabiting cellulose baits, water columns, and sediments of two freshwater lakes was determined by quantitative PCR (qPCR) of reverse-transcribed 16S rRNA. Micromonospora spp. were shown to be significant members of the active bacterial population colonizing cellulosic substrates in the lake sediment, and their increased prevalence with greater depth was confirmed by enumeration of CFU.


Asunto(s)
Celulosa/metabolismo , Agua Dulce/microbiología , Sedimentos Geológicos/microbiología , Micromonospora/aislamiento & purificación , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Carga Bacteriana/métodos , ADN Bacteriano/química , ADN Bacteriano/genética , ADN Ribosómico/química , ADN Ribosómico/genética , Micromonospora/genética , Datos de Secuencia Molecular , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN
12.
Microb Ecol ; 63(2): 267-81, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22213055

RESUMEN

The phylum Fibrobacteres currently comprises one formal genus, Fibrobacter, and two cultured species, Fibrobacter succinogenes and Fibrobacter intestinalis, that are recognised as major bacterial degraders of lignocellulosic material in the herbivore gut. Historically, members of the genus Fibrobacter were thought to only occupy mammalian intestinal tracts. However, recent 16S rRNA gene-targeted molecular approaches have demonstrated that novel centres of variation within the genus Fibrobacter are present in landfill sites and freshwater lakes, and their relative abundance suggests a potential role for fibrobacters in cellulose degradation beyond the herbivore gut. Furthermore, a novel subphylum within the Fibrobacteres has been detected in the gut of wood-feeding termites, and proteomic analyses have confirmed their involvement in cellulose hydrolysis. The genome sequence of F. succinogenes rumen strain S85 has recently suggested that within this group of organisms a "third" way of attacking the most abundant form of organic carbon in the biosphere, cellulose, has evolved. This observation not only has evolutionary significance, but the superior efficiency of anaerobic cellulose hydrolysis by Fibrobacter spp., in comparison to other cellulolytic rumen bacteria that typically utilise membrane-bound enzyme complexes (cellulosomes), may be explained by this novel cellulase system. There are few bacterial phyla with potential functional importance for which there is such a paucity of phenotypic and functional data. In this review, we highlight current knowledge of the Fibrobacteres phylum, its taxonomy, phylogeny, ecology and potential as a source of novel glycosyl hydrolases of biotechnological importance.


Asunto(s)
ADN Bacteriano/genética , Microbiología Ambiental , Fibrobacter/fisiología , Fibrobacteres/clasificación , Tracto Gastrointestinal/microbiología , Animales , Fibrobacter/clasificación , Fibrobacter/genética , Fibrobacter/aislamiento & purificación , Fibrobacteres/genética , Fibrobacteres/aislamiento & purificación , Tracto Gastrointestinal/metabolismo , Isópteros/metabolismo , Isópteros/microbiología , Lagos , Mamíferos/metabolismo , Mamíferos/microbiología , Filogenia , Eliminación de Residuos
13.
ISME Commun ; 2: 34, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36373138

RESUMEN

The distribution and diversity of RNA viruses in soil ecosystems are largely unknown, despite their significant impact on public health, ecosystem functions, and food security. Here, we characterise soil RNA viral communities along an altitudinal productivity gradient of peat, managed grassland and coastal soils. We identified 3462 viral contigs in RNA viromes from purified virus-like-particles in five soil-types and assessed their spatial distribution, phylogenetic diversity and potential host ranges. Soil types exhibited minimal similarity in viral community composition, but with >10-fold more viral contigs shared between managed grassland soils when compared with peat or coastal soils. Phylogenetic analyses predicted soil RNA viral communities are formed from viruses of bacteria, plants, fungi, vertebrates and invertebrates, with only 12% of viral contigs belonging to the bacteria-infecting Leviviricetes class. 11% of viral contigs were found to be most closely related to members of the Ourmiavirus genus, suggesting that members of this clade of plant viruses may be far more widely distributed and diverse than previously thought. These results contrast with soil DNA viromes which are typically dominated by bacteriophages. RNA viral communities, therefore, have the potential to exert influence on inter-kingdom interactions across terrestrial biomes.

14.
Sci Total Environ ; 808: 151916, 2022 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-34826466

RESUMEN

Wastewater-based epidemiology (WBE) has become a complimentary surveillance tool during the SARS-CoV-2 pandemic. Viral concentration methods from wastewater are still being optimised and compared, whilst viral recovery under different wastewater characteristics and storage temperatures remains poorly understood. Using urban wastewater samples, we tested three viral concentration methods; polyethylene glycol precipitation (PEG), ammonium sulphate precipitation (AS), and CP select™ InnovaPrep® (IP) ultrafiltration. We found no major difference in SARS-CoV-2 and faecal indicator virus (crAssphage) recovery from wastewater samples (n = 46) using these methods, PEG slightly (albeit non-significantly), outperformed AS and IP for SARS-CoV-2 detection, as a higher genome copies per litre (gc/l) was recorded for a larger proportion of samples. Next generation sequencing of 8 paired samples revealed non-significant differences in the quality of data between AS and IP, though IP data quality was slightly better and less variable. A controlled experiment assessed the impact of wastewater suspended solids (turbidity; 0-400 NTU), surfactant load (0-200 mg/l), and storage temperature (5-20 °C) on viral recovery using the AS and IP methods. SARS-CoV-2 recoveries were >20% with AS and <10% with IP in turbid samples, whilst viral recoveries for samples with additional surfactant were between 0-18% for AS and 0-5% for IP. Turbidity and sample storage temperature combined had no significant effect on SARS-CoV-2 recovery (p > 0.05), whilst surfactant and storage temperature combined were significant negative correlates (p < 0.001 and p < 0.05, respectively). In conclusion, our results show that choice of methodology had small effect on viral recovery of SARS-CoV-2 and crAssphage in wastewater samples within this study. In contrast, sample turbidity, storage temperature, and surfactant load did affect viral recovery, highlighting the need for careful consideration of the viral concentration methodology used when working with wastewater samples.


Asunto(s)
COVID-19 , Aguas Residuales , Humanos , SARS-CoV-2 , Tensoactivos , Temperatura
16.
Water Res ; 203: 117568, 2021 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-34450465

RESUMEN

The discharge of wastewater-derived viruses in aquatic environments impacts catchment-scale virome composition. To explore this, we used viromic analysis of RNA and DNA virus-like particles to holistically track virus communities entering and leaving wastewater treatment plants and the connecting river catchment system and estuary. We reconstructed >40 000 partial viral genomes into 10 149 species-level groups, dominated by dsDNA and (+)ssRNA bacteriophages (Caudoviricetes and Leviviricetes) and a small number of genomes that could pose a risk to human health. We found substantial viral diversity and geographically distinct virus communities associated with different wastewater treatment plants. River and estuarine water bodies harboured more diverse viral communities in downstream locations, influenced by tidal movement and proximity to wastewater treatment plants. Shellfish and beach sand were enriched in viral communities when compared with the surrounding water, acting as entrapment matrices for virus particles. Extensive phylogenetic analyses of environmental-derived and reference sequences showed the presence of human-associated sapovirus GII in all sample types, multiple rotavirus A strains in wastewater and a diverse set of picorna-like viruses associated with shellfish. We conclude that wastewater-derived viral genetic material is commonly deposited in the environment and can be traced throughout the freshwater-marine continuum of the river catchment, where it is influenced by local geography, weather events and tidal effects. Our data illustrate the utility of viromic analyses for wastewater- and environment-based ecology and epidemiology, and we present a conceptual model for the circulation of all types of viruses in a freshwater catchment.


Asunto(s)
Virus , Aguas Residuales , Humanos , Filogenia , Ríos , Viroma , Virus/genética
17.
Front Microbiol ; 12: 608888, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33679634

RESUMEN

The fecal indicator organism (FIO) Escherichia coli is frequently used as a general indicator of sewage contamination and for evaluating the success of shellfish cleaning (depuration) processes. To evaluate the robustness of this approach, the accumulation, retention, and depuration of non-pathogenic E. coli, pathogenic E. coli O157:H7 and norovirus GII (NoV GII) RNA were evaluated using a combination of culture-based (E. coli) and molecular methods (E. coli, NoV GII) after exposure of mussels (Mytilus edulis) to water contaminated with human feces. We simulated water contamination after a point-source release from a combined sewer overflow (CSO) where untreated wastewater is released directly into the coastal zone. All three microbiological indicators accumulated rapidly in the mussels, reaching close to maximum concentration within 3 h of exposure, demonstrating that short CSO discharges pose an immediate threat to shellfish harvesting areas. Depuration (72 h) in clean water proved partially successful at removing both pathogenic and non-pathogenic E. coli from shellfish tissue, but failed to eradicate NoV GII RNA. We conclude that current EU standards for evaluating microbiological risk in shellfish are inadequate for protecting consumers against exposure to human norovirus GII found in polluted marine waters.

18.
Methods Protoc ; 4(1)2021 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-33672247

RESUMEN

Wastewater-based epidemiology has become an important tool for the surveillance of SARS-CoV-2 outbreaks. However, the detection of viruses in sewage is challenging and to date there is no standard method available which has been validated for the sensitive detection of SARS-CoV-2. In this paper, we describe a simple concentration method based on polyethylene glycol (PEG) precipitation, followed by RNA extraction and a one-step quantitative reverse transcription PCR (qRT-PCR) for viral detection in wastewater. PEG-based concentration of viruses is a simple procedure which is not limited by the availability of expensive equipment and has reduced risk of disruption to consumable supply chains. The concentration and RNA extraction steps enable 900-1500× concentration of wastewater samples and sufficiently eliminates the majority of organic matter, which could inhibit the subsequent qRT-PCR assay. Due to the high variation in the physico-chemical properties of wastewater samples, we recommend the use of process control viruses to determine the efficiency of each step. This procedure enables the concentration and the extraction the DNA/RNA of different viruses and hence can be used for the surveillance of different viral targets for the comprehensive assessment of viral diseases in a community.

19.
Water Res ; 200: 117214, 2021 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-34058486

RESUMEN

SARS-CoV-2 and the resulting COVID-19 pandemic represents one of the greatest recent threats to human health, wellbeing and economic growth. Wastewater-based epidemiology (WBE) of human viruses can be a useful tool for population-scale monitoring of SARS-CoV-2 prevalence and epidemiology to help prevent further spread of the disease, particularly within urban centres. Here, we present a longitudinal analysis (March-July 2020) of SARS-CoV-2 RNA prevalence in sewage across six major urban centres in the UK (total population equivalent 3 million) by q(RT-)PCR and viral genome sequencing. Our results demonstrate that levels of SARS-CoV-2 RNA generally correlated with the abundance of clinical cases recorded within the community in large urban centres, with a marked decline in SARS-CoV-2 RNA abundance following the implementation of lockdown measures. The strength of this association was weaker in areas with lower confirmed COVID-19 case numbers. Further, sequence analysis of SARS-CoV-2 from wastewater suggested that multiple genetically distinct clusters were co-circulating in the local populations covered by our sample sites, and that the genetic variants observed in wastewater reflected similar SNPs observed in contemporaneous samples from cases tested in clinical diagnostic laboratories. We demonstrate how WBE can be used for both community-level detection and tracking of SARS-CoV-2 and other virus' prevalence, and can inform public health policy decisions. Although, greater understanding of the factors that affect SARS-CoV-2 RNA concentration in wastewater are needed for the full integration of WBE data into outbreak surveillance. In conclusion, our results lend support to the use of routine WBE for monitoring of SARS-CoV-2 and other human pathogenic viruses circulating in the population and assessment of the effectiveness of disease control measures.


Asunto(s)
COVID-19 , SARS-CoV-2 , Control de Enfermedades Transmisibles , Humanos , Pandemias , ARN Viral , Reino Unido , Aguas Residuales
20.
Front Microbiol ; 12: 735022, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34594317

RESUMEN

Soil organic matter is composed of a variety of carbon (C) forms. However, not all forms are equally accessible to soil microorganisms. Deprivation of C inputs will cause changes in the physical and microbial community structures of soils; yet the trajectories of such changes are not clear. We assessed microbial communities using phospholipid fatty acid profiling, metabarcoding, CO2 emissions, and functional gene microarrays in a decade-long C deprivation field experiment. We also assessed changes in a range of soil physicochemical properties, including using X-ray Computed Tomography imaging to assess differences in soil structure. Two sets of soils were deprived of C inputs by removing plant inputs for 10 years and 1 year, respectively. We found a reduction in diversity measures, after 10 years of C deprivation, which was unexpected based on previous research. Fungi appeared to be most impacted, likely due to competition for scarce resources after exhausting the available plant material. This suggestion was supported by evidence of bioindicator taxa in non-vegetated soils that may directly compete with or consume fungi. There was also a reduction in copies of most functional genes after 10 years of C deprivation, though gene copies increased for phytase and some genes involved in decomposing recalcitrant C and methanogenesis. Additionally, soils under C deprivation displayed expected reductions in pH, organic C, nitrogen, and biomass as well as reduced mean pore size, especially in larger pores. However, pore connectivity increased after 10 years of C deprivation contrary to expectations. Our results highlight concurrent collapse of soil structure and biodiversity following long-term C deprivation. Overall, this study shows the negative trajectory of continuous C deprivation and loss of organic matter on a wide range of soil quality indicators and microorganisms.

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