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1.
Food Chem ; 400: 134107, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36087481

RESUMO

This study evaluated the inoculation of Meyerozyma guilliermondii and Bacillus licheniformis, separately or in co-culture, in wet-processed conilon coffee. Wet fermentation was conducted for 48 h. Mesophilic bacteria, lactic acid bacteria, yeasts, and filamentous fungi were counted during fermentation. The inoculation of B. licheniformis and M. guilliermondii stimulated the multiplication of lactic acid bacteria. Acetic, citric, lactic, oxalic, malic, succinic, tartaric acids, glucose, and fructose were identified in all treatments at different concentrations. Methyl salicylate, 2-heptanol, 2-nonanol, and heptanone were found during fermentation. Methylpyrazine, 2,6-dimethylpyrazine, 2,5-dimethylpyrazine, and 3-ethyl-2,5-dimethylpyrazine identified after roasting assigned notes of "almond" and "chocolate" to the beverages. All treatments were classified as "premium," with the B. licheniformis treatment receiving the highest score. Bacillus licheniformis obtained better performance in fermentation, increasing coffee score and producing volatile compounds that provided positive sensory notes to the beverage.


Assuntos
Coffea , Lactobacillales , Bactérias/genética , Café/microbiologia , Frutose , Glucose , Heptanol , Leveduras
2.
Food Chem ; 399: 133989, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36041337

RESUMO

To characterize the involvement of microorganisms in amino acid degradation and fish quality deterioration, three major grass carp spoilage bacteria were artificially inoculated in amino acid solutions (in-vitro) and grass carp flesh (in-situ). Results showed that Pseudomonas putida largely degraded free amino acids and produced 3.78 mM/100 g ammonia in grass carp flesh, relying on its high amino acid deamination1 activity. Aeromonas rivipollensis produced 3-Methyl-butanol and 2-Methyl-butanol through leucine and isoleucine degradation. Shewanella putrefaciens had potent ornithine-decarboxylation activity (423.91 × 10-9 µg/CFU) and released 22.98 mg/kg putrescine in situ. S. putrefaciens could produce more putrescine when cooperating with P. putida through the arginine deiminase pathway. To conclude, the biochemical activities identified through in-vitro tests correlated well with quality changes in inoculated grass carp flesh. The outcomes of this study provided fundamental information on the spoilage mechanisms of freshwater fish and important guidance for the development of quality control strategies.


Assuntos
Carpas , Contaminação de Alimentos , Alimentos Marinhos , Shewanella putrefaciens , Aminoácidos , Animais , Butanóis , Proteínas de Peixes , Putrescina , Alimentos Marinhos/microbiologia
3.
Food Chem ; 400: 134016, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36084588

RESUMO

This work aims to investigate antifungal, mycotoxin inhibitory efficacy of the hop essential oil (HEO) nanoemulsion and their mode of action (MOA) against Fusarium graminearum isolate, a fungal pathogen causing Fusarium Head Blight (FHB) in cereal crops. The HEO, primarily consisting of terpenes and terpenoids, was encapsulated in nanoemulsion droplets. Physically stable HEO-in-water nanoemulsion was fabricated using 0.5 wt% of tween 80 and 5 wt% oil phase comprising 30 % of Ostwald ripening inhibitor and 70 % of HEO. In terms of antifungal effect, HEO nanoemulsion could not only effectively inhibit mycelial growth and spore germination of F. graminearum isolates, but also remarkably suppress the production of deoxynivalenol (DON) and its derivatives in rice culture by applying 750 µg of HEO/g rice. Our studies on the MOA showed that HEO nanoemulsion could alter the contents of total lipid and chitin in outer cell membrane as well as damaging cytoplasmic membrane.


Assuntos
Fusarium , Micotoxinas , Óleos Voláteis , Antifúngicos/metabolismo , Antifúngicos/farmacologia , Quitina/metabolismo , Fusarium/metabolismo , Micotoxinas/metabolismo , Óleos Voláteis/metabolismo , Óleos Voláteis/farmacologia , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Polissorbatos/farmacologia , Terpenos/metabolismo , Água/metabolismo
4.
Food Chem ; 398: 133884, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-35964575

RESUMO

Development of selective and sensitive methods for the detection of 2, 6-dipicolinic acid (DPA), a biomarker produced by bacterial spores, is of great significance for maintaining public health and food safety. Herein, a ratiometric fluorescence strategy using graphene carbon nitride (g-C3N4) coupled with Eu3+ is designed for the assay of DPA. As the concentration of DPA increases, the emission intensity of g-C3N4 kept constant which acted as a stable internal reference, while the fluorescence of Eu3+ was enhanced obviously due to the antenna effect. The linear calibration ranged from 0.1 to 15 µM with a detection limit of 13 nM was obtained. More Importantly, a paper-based sensor with a smartphone was successfully combined to perform colorimetric and visual detection of DPA in situ. This method has good performance for the detection of DPA, which is expected to broaden the application prospects of preliminary biomarker monitoring.


Assuntos
Antraz , Antraz/diagnóstico , Antraz/microbiologia , Biomarcadores , Európio , Corantes Fluorescentes , Humanos , Nitrilas , Ácidos Picolínicos , Smartphone
5.
Food Chem ; 398: 133795, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-35987006

RESUMO

This study presents a novel method for predicting the shelf life of pork in real-time based on front-face fluorescence excitation-emission matrices (EEMs). The total viable count (TVC) of bacteria was used as the indicator of microbial spoilage in the pork samples. Modified Gompertz and square root equations were used to establish models for the trends in microbial growth and for predicting the shelf life, the R2 values of the fitting equation at different temperatures were all greater than 0.95. The fluorescence intensity ratio of oxidation product to tryptophan (FOX/Trp) was highly correlated with the quality deterioration of pork and was therefore used to establish a quantitative model of TVC values by linear regression with Rc2 and Rp2 values of 0.914 and 0.906, respectively. The mean absolute errors between the remaining shelf life predicted by fluorescence EEMs and the measured values at three storage temperatures were less than 1 day.


Assuntos
Carne de Porco , Carne Vermelha , Animais , Bactérias/genética , Microbiologia de Alimentos , Conservação de Alimentos/métodos , Modelos Lineares , Carne Vermelha/microbiologia , Suínos , Temperatura
6.
Microbiology (Reading) ; 168(2)2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35133955

RESUMO

Virulent non-tuberculous Mycobacteria (NTMs) successfully reside and multiply within the phagosomes of phagocytic cells such as monocytes and macrophages. Macrophages play a very important role in the innate clearance of intracellular pathogens including NTMs. Attenuated Mycobacterium avium subsp. hominissuis 100 enters macrophages but is incapable of escaping these cells via canonical mycobacteria escape mechanisms. Alternatively, virulent Mycobacterium avium subsp. hominissuis 104 and Mycobacterium abscessus subsp. abscessus are able to modify macrophages to suit their growth, survival and ultimately escape from macrophages, while non-virulent Mycobacterium smegmatis is readily killed by macrophages. In this study we focused on early infection of macrophages with NTMs to determine the phenotypic response of macrophages, M1 or M2 differentiation, and phosphorylation alterations that can affect cellular response to invading bacteria. Our findings indicate that infection of the macrophage with MAH 100 and M. smegmatis favours the development of M1 macrophage, a pro-inflammatory phenotype associated with the killing of intracellular pathogens, while infection of the macrophage with MAH 104 and M. abscessus favoured the development of M2 macrophage, an anti-inflammatory phenotype associated with the healing process. Interference with the host post-translational mechanisms, such as protein phosphorylation, is a key strategy used by many intracellular bacterial pathogens to modulate macrophage phenotype and subvert macrophage function. By comparing protein phosphorylation patterns of infected macrophages, we observed that uptake of both MAH 100 and M. smegmatis resulted in MARCKS-related protein phosphorylation, which has been associated with macrophage activation. In contrast, in macrophages infected with MAH 104 and M. abscessus, methionine adenosyltransferase IIß, an enzyme that catalyses the biosynthesis of S-adenosylmethionine, a methyl donor for DNA methylation. Inhibition of DNA methylation with 5-aza-2 deoxycytidine, significantly impaired the survival of MAH 104 in macrophages. Our findings suggest that the virulent MAH 104 and M. abscessus enhance its survival in the macrophage possibly through interference with the epigenome responses.


Assuntos
Macrófagos , Mycobacterium avium , Ativação de Macrófagos , Macrófagos/microbiologia , Mycobacterium smegmatis/genética
7.
Environ Entomol ; 51(1): 94-107, 2022 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-34864906

RESUMO

Insects harbor bacterial endosymbionts that provide their hosts with nutritional benefit or with protection against natural enemies, plant defenses, insecticides, or abiotic stresses. We used directed sequencing of 16S rDNA to identify and compare endosymbionts of Bactericera maculipennis (Crawford) and the western, central, and northwestern haplotypes of B. cockerelli (Sulc) (Hemiptera: Psylloidea: Triozidae). Both species are native to North America, are known to harbor the plant pathogen 'Candidatus Liberibacter solanacearum' and develop on shared host plants within the Convolvulaceae. The Old-World species Heterotrioza chenopodii (Reuter) (Psylloidea: Triozidae), now found in North America, was included as an outgroup. 16S sequencing confirmed that both Bactericera species harbor 'Candidatus Liberibacter solanacearum' and revealed that both species harbor unique strains of Wolbachia and Sodalis. However, the presence of Wolbachia and Sodalis varied among haplotypes of B. cockerelli. The central and western haplotypes harbored the same strains of Wolbachia, which was confirmed by Sanger sequencing of the wsp and ftsZ genes. Wolbachia was also detected in very low abundance from the northwestern haplotype by high-throughput sequencing of 16S but was not detected from this haplotype by PCR screening. The northwestern and central haplotypes also harbored Sodalis, which was not detected in the western haplotype. Heterotrioza chenopodii harbored an entirely different community of potential endosymbionts compared with the Bactericera spp. that included Rickettsia and an unidentified bacterium in the Enterobacteriaceae. Results of this study provide a foundation for further research on the interactions between psyllids and their bacterial endosymbionts.


Assuntos
Hemípteros , Rhizobiaceae , Solanum tuberosum , Animais , Bactérias/genética , Haplótipos , Hemípteros/microbiologia , Doenças das Plantas/microbiologia , Solanum tuberosum/microbiologia
8.
BMC Vet Res ; 18(1): 352, 2022 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-36127697

RESUMO

BACKGROUND: Tuberculosis (TB) due to Mycobacterium caprae is endemic in goat herds and free-ranging wild boars in Spain, causing infections in other livestock or wild animals to a lesser extent. TB infection in foxes is infrequently reported and they are usually considered spillover hosts of TB. CASE PRESENTATION: A blind, depressed and severely emaciated red fox (Vulpes vulpes) was admitted to a rehabilitation center. After clinical examination it was humanely sacrificed. At necropsy, generalized TB lesions were observed that were subsequently confirmed by histopathology along with a co-infection with canine distemper virus. M. caprae was isolated from mycobacterial culture and spoligotype SB0415 was identified. Whole genome sequencing (WGS) of the isolated M. caprae was carried out and single nucleotide polymorphisms (SNP) were compared with other sequences of M. caprae isolated from livestock and wildlife of the same area throughout the last decade. CONCLUSIONS: This is the first reported case of TB due to M. caprae in a fox in the Iberian Peninsula. WGS and SNP analysis, together with spatial-temporal investigations, associated this case with recent M. caprae outbreaks in cattle and goat herds of the area. The results indicated transmission of M. caprae between livestock and the fox, suggesting that this species may occasionally play a role in the epidemiology of animal TB.


Assuntos
Doenças dos Bovinos , Doenças das Cabras , Mycobacterium bovis , Doenças dos Suínos , Tuberculose , Animais , Animais Selvagens , Bovinos , Raposas , Cabras/microbiologia , Granuloma/veterinária , Gado , Mycobacterium bovis/genética , Sus scrofa/microbiologia , Suínos , Tuberculose/epidemiologia , Tuberculose/microbiologia , Tuberculose/veterinária
9.
PLoS One ; 17(9): e0274645, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36129912

RESUMO

Anthrax is a zoonosis caused by the environmentally maintained, spore-forming bacterium Bacillus anthracis, affecting humans, livestock, and wildlife nearly worldwide. Bacterial spores are ingested, inhaled, and may be mechanically transmitted by biting insects or injection as occurs during heroin-associated human cases. Herbivorous hoofstock are very susceptible to anthrax. When these hosts die of anthrax, a localized infectious zone (LIZ) forms in the area surrounding the carcass as it is scavenged and decomposes, where viable populations of vegetative B. anthracis and spores contaminate the environment. In many settings, necrophagous flies contaminate the outer carcass, surrounding soils, and vegetation with viable pathogen while scavenging. Field observations in Texas have confirmed this process and identified primary browse species (e.g., persimmon) are contaminated. However, there are limited data available on B. anthracis survival on environmental substrates immediately following host death at a LIZ. Toward this, we simulated fly contamination by inoculating live-attenuated, fully virulent laboratory-adapted, and fully virulent wild B. anthracis strains on untreated leaves and rocks for 2, 5, and 7 days. At each time point after inoculation, the number of vegetative cells and spores were determined. Sporulation rates were extracted from these different time points to enable comparison of sporulation speeds between B. anthracis strains with different natural histories. We found all B. anthracis strains used in this study could multiply for 2 or more days post inoculation and persist on leaves and rocks for at least seven days with variation by strain. We found differences in sporulation rates between laboratory-adapted strains and wild isolates, with the live-attenuated strain sporulating fastest, followed by the wild isolates, then laboratory-adapted virulent strains. Extrapolating our wild strain lab results to potential contamination, a single blow fly may contaminate leaves with up to 8.62 x 105 spores per day and a single carcass may host thousands of flies. Replication outside of the carcass and rapid sporulation confirms the LIZ extends beyond the carcass for several days after formation and supports the necrophagous fly transmission pathway for amplifying cases during an outbreak. We note caution must be taken when extrapolating replication and sporulation rates from live-attenuated and laboratory-adapted strains of B. anthracis.


Assuntos
Antraz , Bacillus anthracis , Dípteros , Animais , Animais Selvagens , Antraz/epidemiologia , Antraz/microbiologia , Antraz/veterinária , Dípteros/microbiologia , Surtos de Doenças , Heroína , Humanos , Solo , Esporos Bacterianos
10.
PLoS One ; 17(9): e0275087, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36129948

RESUMO

In preterm and term infants who require intermediate or intensive care Methicillin-resistant Staphylococcus aureus (MRSA) infection can lead to significant morbidity. In this study MRSA colonization and infection were assessed in a mixed tertiary neonatal intensive and intermediate care unit in Germany over an 8-year period (2013-2020). We investigated patient-related factors, associated with nosocomial MRSA acquisition, and we discuss our infection control concept for MRSA. Of 3488 patients treated during the study period, 24 were MRSA positive patients, corresponding to 26 patient hospital stays. The incidence was 0.7 MRSA patients per 100 patients. The incidence density was 0.4 MRSA patient hospital stays per 1000 patient days. Twelve patients (50%) acquired MRSA in the hospital. One patient developed a hospital acquired MRSA bloodstream infection 9 days after birth (i.e., 0.03% of all patients on the ward during the study period). A total of 122 patients had to be screened to detect one MRSA positive patient. In a logistic regression model, the use of 3rd generation intravenous cephalosporin (cefotaxim) was associated with nosocomial MRSA acquisition compared with matched control patients who did not acquire MRSA. In sum, the burden of MRSA colonization and infection in the ward was low during the study period. A comprehensive infection control concept that included microbiologic colonization screening, prospective infection surveillance together with isolation and emphasis on basic hygiene measures is essential to handle MRSA in this specialized setting.


Assuntos
Infecção Hospitalar , Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Cefotaxima , Cefalosporinas , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/microbiologia , Infecção Hospitalar/prevenção & controle , Humanos , Lactente , Recém-Nascido , Controle de Infecções , Estudos Prospectivos , Estudos Retrospectivos , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/prevenção & controle
11.
Sci Data ; 9(1): 578, 2022 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-36130969

RESUMO

Wastewater treatment plant (WWTP) discharges alter water quality and microbial communities by introducing human-associated bacteria in the environment and by altering microbial communities. To fully understand this impact, it is crucial to study whether WWTP discharges affect water and sediments microbial communities in comparable ways and whether such effects depend on specific environmental variables. Here, we present a dataset investigating the impact of a WWTP on water quality and bacterial communities by comparing samples collected directly from the WWTP outflow to surface waters and sediments at two sites above and two sites below it over a period of five months. When possible, we measured five physicochemical variables (e.g., temperature, turbidity, conductivity, dissolved oxygen, and salinity), four bioindicators (e.g., Escherichia coli, total coliforms, Enterococcus sp., and endotoxins), and two molecular indicators (e.g., intI1's relative abundance, and 16S rRNA gene profiling). Preliminary results suggest that bioindicators correlate with environmental variables and that bacterial communities present in the water tables, sediments, and treated water differ greatly in composition and structure.


Assuntos
Águas Residuárias , Qualidade da Água , Bactérias , Endotoxinas , Biomarcadores Ambientais , Sedimentos Geológicos/microbiologia , Humanos , Oxigênio , RNA Ribossômico 16S/genética
12.
BMC Microbiol ; 22(1): 222, 2022 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-36131235

RESUMO

BACKGROUND: Pseudomonas spp. promotes plant growth and colonizes a wide range of environments. During the annotation of a Coffea arabica ESTs database, we detected a considerable number of contaminant Pseudomonas sequences, specially associated with leaves. The genome of a Pseudomonas isolated from coffee leaves was sequenced to investigate in silico information that could offer insights about bacterial adaptation to coffee phyllosphere. In parallel, several experiments were performed to confirm certain physiological characteristics that could be associated with phyllospheric behavior. Finally, in vivo and in vitro experiments were carried out to verify whether this isolate could serve as a biocontrol agent against coffee rust and how the isolate could act against the infection.  RESULTS: The isolate showed several genes that are associated with resistance to environmental stresses, such as genes encoding heat/cold shock proteins, antioxidant enzymes, carbon starvation proteins, proteins that control osmotic balance and biofilm formation. There was an increase of exopolysaccharides synthesis in response to osmotic stress, which may protect cells from dessication on phyllosphere. Metabolic pathways for degradation and incorporation into citrate cycle of phenolic compounds present in coffee were found, and experimentally confirmed. In addition, MN1F was found to be highly tolerant to caffeine. The experiments of biocontrol against coffee leaf rust showed that the isolate can control the progress of the disease, most likely through competition for resources. CONCLUSION: Genomic analysis and experimental data suggest that there are adaptations of this Pseudomonas to live in association with coffee leaves and to act as a biocontrol agent.


Assuntos
Basidiomycota , Coffea , Antioxidantes , Basidiomycota/genética , Cafeína , Carbono , Citratos , Coffea/microbiologia , Proteínas e Peptídeos de Choque Frio , Genômica , Pseudomonas/genética
13.
BMC Plant Biol ; 22(1): 452, 2022 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-36131258

RESUMO

BACKGROUND: European canker, caused by the fungal pathogen Neonectria ditissima, is an economically damaging disease in apple producing regions of the world - especially in areas with moderate temperatures and high rainfall. The pathogen has a wide host range of hardwood perennial species, causing trunk cankers, dieback and branch lesions in its hosts. Although apple scion germplasm carrying partial resistance to the disease has been described, little is still known of the genetic basis for this quantitative resistance. RESULTS: Resistance to Neonectria ditissima was studied in a multiparental population of apple scions using several phenotyping methods. The studied population consists of individuals from multiple families connected through a common pedigree. The degree of disease of each individual in the population was assessed in three experiments: artificial inoculations of detached dormant shoots, potted trees in a glasshouse and in a replicated field experiment. The genetic basis of the differences in disease was studied using a pedigree-based analysis (PBA). Three quantitative trait loci (QTL), on linkage groups (LG) 6, 8 and 10 were identified in more than one of the phenotyping strategies. An additional four QTL, on LG 2, 5, 15 and 16 were only identified in the field experiment. The QTL on LG2 and 16 were further validated in a biparental population. QTL effect sizes were small to moderate with 4.3 to 19% of variance explained by a single QTL. A subsequent analysis of QTL haplotypes revealed a dynamic response to this disease, in which the estimated effect of a haplotype varied over the field time-points. CONCLUSIONS: This study describes the first identified QTL associated with resistance to N. ditissima in apple scion germplasm. The results from this study show that QTL present in germplasm commonly used in apple breeding have a low to medium effect on resistance to N. ditissima. Hence, multiple QTL will need to be considered to improve resistance through breeding.


Assuntos
Hypocreales , Malus , Resistência à Doença/genética , Hypocreales/fisiologia , Malus/genética , Malus/microbiologia , Melhoramento Vegetal , Doenças das Plantas/genética , Doenças das Plantas/microbiologia
14.
Front Immunol ; 13: 994224, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36131927

RESUMO

Coccidiosis is an economically significant protozoan disease and an intracellular parasite that significantly impacts poultry production. The gastrointestinal tract microbiota plays a central role in host health and metabolism, and these microbes enhance chickens' immune systems and nutrient absorption. In this study, we analyzed the abundance and diversity of microbiota of the jejunum and cecum of a dual-purpose indigenous Horro chicken following Eimeria maxima infection. We compared microbial abundance, composition, and diversity at the 4- and 7- days post-infection using 16S rRNA gene sequencing. We obtained, on average, 147,742 and 132,986 high-quality sequences per sample for jejunum and cecum content, respectively. Firmicutes, Proteobacteria, Campilobacterota and Bacteroidota were the major microbial phylum detected in the jejunum content. Firmicutes were the dominant phylum for 4- and 7-days jejunum control groups accounting for (>60% of the sequences). In the infected group Campilobacterota was the dominant phylum in the jejunum (> 24% of sequences) at 4-and 7-days post-infection groups, while Proteobacteria was predominant at 4- and 7-days post-infection of the cecum (> 40% of the sequences). The microbial genus Lactobacillus and Helicobacter were found in the jejunum, while Alistipes, Barnesiella and Faecalibacterium were detected in the cecum. In the jejunum, Helicobacter was dominant at 4 -and-7 days post-infection (≥24%), and Lactobacillus was dominant at 4 -and 7- days in the control group (> 50%). In 4- and 7-days post-infection, Alistipes genus was the more prevalent (> 38%) in the cecum. Thus, clear differences were observed in the bacterial microbiota distribution and abundance between the jejunum and cecum, as well as between infected and control groups for both tissues. The results indicate that chicken intestinal microbial imbalance (dysbiosis) is associated with Eimeria parasite infection and will likely affect the host-microbial non-pathogenic and pathogenic molecular interactions.


Assuntos
Eimeria , Microbioma Gastrointestinal , Doenças das Aves Domésticas , Animais , Ceco/microbiologia , Galinhas/genética , Microbioma Gastrointestinal/genética , Jejuno , Doenças das Aves Domésticas/microbiologia , RNA Ribossômico 16S/genética
15.
Front Cell Infect Microbiol ; 12: 984140, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36132989

RESUMO

The Burkholderia cepacia complex (BCC) is a group of opportunistic pathogens, including Burkholderia cepacia, Burkholderia multivorans, Burkholderia vietnamiensis and Burkholderia ambifaria, which can cause severe respiratory tract infections and lead to high mortality rates among humans. The early diagnosis and effective treatment of BCC infection are therefore crucial. In this study, a novel and rapid recombinase-aided amplification (RAA) assay targeting the 16S rRNA gene was developed for BCC detection. The protocol for this RAA assay could be completed in 10 min at 39°C, with a sensitivity of 10 copies per reaction and no cross-reactivity with other pathogens. To characterize the effectiveness of the RAA assay, we further collected 269 clinical samples from patients with bacterial pneumonia. The sensitivity and specificity of the RAA assay were 100% and 98.5%, respectively. Seven BCC-infected patients were detected using the RAA assay, and three BCC strains were isolated from the 269 clinical samples. Our data showed that the prevalence of BCC infection was 2.60%, which is higher than the 1.40% reported in previous studies, suggesting that high sensitivity is vital to BCC detection. We also screened a patient with B. vietnamiensis infection using the RAA assay in clinic, allowing for appropriate treatment to be initiated rapidly. Together, these data indicate that the RAA assay targeting the 16S rRNA gene can be applied for the early and rapid detection of BCC pathogens in patients with an uncharacterized infection who are immunocompromised or have underlying diseases, thereby providing guidance for effective treatment.


Assuntos
Infecções por Burkholderia , Complexo Burkholderia cepacia , Fibrose Cística , Infecções por Burkholderia/diagnóstico , Complexo Burkholderia cepacia/genética , Fibrose Cística/microbiologia , Genes de RNAr , Humanos , RNA Ribossômico 16S/genética , Recombinases
16.
Environ Sci Pollut Res Int ; 29(44): 67466-67482, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36056283

RESUMO

The Vibrionaceae family groups genetically and metabolically diverse bacteria thriving in all marine environments. Despite often representing a minor fraction of bacterial assemblages, members of this family can exploit a wide variety of nutritional sources, which makes them important players in biogeochemical dynamics. Furthermore, several Vibrionaceae species are well-known pathogens, posing a threat to human and animal health. Here, we applied the phylogenetic placement coupled with a consensus-based approach using 16S rRNA gene amplicon sequencing, aiming to reach a reliable and fine-level Vibrionaceae characterization and identify the dynamics of blooming, ecologically important, and potentially pathogenic species in different sites of the northern Adriatic Sea. Water samples were collected monthly at a Long-Term Ecological Research network site from 2018 to 2021, and in spring and summer of 2019 and 2020 at two sites affected by depurated sewage discharge. The 41 identified Vibrionaceae species represented generally below 1% of the sampled communities; blooms (up to ~ 11%) mainly formed by Vibrio chagasii and Vibrio owensii occurred in summer, linked to increasing temperature and particulate matter concentration. Pathogenic species such as Vibrio anguilllarum, Vibrio tapetis, and Photobacterium damselae were found in low abundance. Depuration plant samples were characterized by a lower abundance and diversity of Vibrionaceae species compared to seawater, highlighting that Vibrionaceae dynamics at sea are unlikely to be related to wastewater inputs. Our work represents a further step to improve the molecular approach based on short reads, toward a shared, updated, and curated phylogeny of the Vibrionaceae family.


Assuntos
Vibrionaceae , Animais , Ecossistema , Monitoramento Ambiental , Genes de RNAr , Humanos , Material Particulado , Filogenia , RNA Ribossômico 16S/genética , Água do Mar/microbiologia , Esgotos , Vibrionaceae/genética , Águas Residuárias , Água
17.
Eur J Clin Microbiol Infect Dis ; 41(10): 1245-1261, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36057762

RESUMO

The aim of our study was to characterize the epidemiological situation concerning nosocomial vancomycin-resistant Enterococcus faecalis of VanA-phenotype (VREfs-VanA) in Poland by investigating their clonal relationships and the vanA-associated mobilome. One-hundred twenty-five clinical isolates of VREfs-VanA collected between 2004 and 2016 were studied by phenotypic assays, multilocus sequence typing (MLST), pulsed-field gel electrophoresis (PFGE), PCR detection of plasmid-specific genes, and Tn1546 structure and localization mapping. Selected isolates were subjected to PFGE-S1, Southern hybridization, genomic sequencing and conjugation experiments. The majority of isolates (97.6%) belonged to clonal complexes CC2 and CC87 of E. faecalis. All isolates were resistant to vancomycin and teicoplanin, and resistance to ciprofloxacin and aminoglycosides (high level) was very prevalent in this group. VanA phenotype was associated with 16 types of Tn1546, carrying insertion sequences IS1216, ISEfa4, IS1251 and IS1542, located on repUS1pVEF1, rep1pIP501, rep2pRE25, rep9pAD1/pTEF2/pCF10 and rep6pS86 replicons. The most common Tn1546 B- and BB-type transposons, harbouring one or two copies of IS1216, were inserted between rep18ap200B and repUS1pVEF1 genes and located on ~ 20 kb and 150-200 kb plasmids. VREfs-VanA in Poland represent a polyclonal group, indicating a number of acquisitions of the vanA determinant. The repUS1pVEF1-vanA plasmids, unique for Poland, were the main factor beyond the acquisition of vancomycin resistance by E. faecalis, circulating in Polish hospitals.


Assuntos
Enterococcus faecium , Infecções por Bactérias Gram-Positivas , Aminoglicosídeos , Proteínas de Bactérias/genética , Carbono-Oxigênio Ligases/genética , Ciprofloxacina , Elementos de DNA Transponíveis , Enterococcus faecalis/genética , Enterococcus faecium/genética , Infecções por Bactérias Gram-Positivas/epidemiologia , Infecções por Bactérias Gram-Positivas/microbiologia , Hospitais , Humanos , Tipagem de Sequências Multilocus , Polônia/epidemiologia , Teicoplanina , Vancomicina
18.
J Agric Food Chem ; 70(37): 11759-11768, 2022 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-36069406

RESUMO

The advanced glycation endproduct carboxymethyllysine and its precursor fructoselysine are present in heated, processed food products and are considered potentially hazardous for human health. Upon dietary exposure, they can be degraded by human colonic gut microbiota, reducing internal exposure. Pronounced interindividual and intraindividual differences in these metabolic degradations were found in anaerobic incubations with human fecal slurries in vitro. The average capacity to degrade fructoselysine was 27.7-fold higher than that for carboxymethyllysine, and degradation capacities for these two compounds were not correlated (R2 = 0.08). Analysis of the bacterial composition revealed that interindividual differences outweighed intraindividual differences, and multiple genera were correlated with the individuals' carboxymethyllysine and fructoselysine degradation capacities (e.g., Akkermansia, Alistipes).


Assuntos
Microbioma Gastrointestinal , Fezes/microbiologia , Produtos Finais de Glicação Avançada/metabolismo , Humanos , Lisina/análogos & derivados , Lisina/metabolismo , RNA Ribossômico 16S
19.
Euro Surveill ; 27(36)2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36082683

RESUMO

BackgroundBloodstream infections (BSI) cause substantial morbidity and mortality.AimWe explored the role of causative pathogens and patient characteristics on the outcome of community-acquired (CA) and healthcare-associated (HA) BSI, with particular interest in early death.MethodsWe used national register data to identify all BSI in Finland during 2004-18. We determined the origin of BSI, patients´ underlying comorbidities and deaths within 2 or 30 days from specimen collection. A time-dependent Cox model was applied to evaluate the impact of patient characteristics and causative pathogens on the hazard for death at different time points.ResultsA total of 173,715 BSI were identified; 22,474 (12.9%) were fatal within 30 days and, of these, 6,392 (28.4%) occurred within 2 days (7.9 deaths/100,000 population). The 2-day case fatality rate of HA-BSI was higher than that of CA-BSI (5.4% vs 3.0%). Patients who died within 2 days were older than those alive on day 3 (76 vs 70 years) and had more severe comorbidities. Compared with other BSI, infections leading to death within 2 days were more often polymicrobial (11.8% vs 6.3%) and caused by Pseudomonas aeruginosa (6.2% vs 2.0%), fungi (2.9% vs 1.4%) and multidrug-resistant (MDR) pathogens (2.2% vs 1.8%), which were also predictors of death within 2 days in the model.ConclusionsOverrepresentation of polymicrobial, fungal, P. aeruginosa and MDR aetiology among BSI leading to early death is challenging concerning the initial antimicrobial treatment. Our findings highlight the need for active prevention and prompt recognition of BSI and appropriate antimicrobial treatment.


Assuntos
Bacteriemia , Infecções Comunitárias Adquiridas , Infecção Hospitalar , Antibacterianos/uso terapêutico , Bacteriemia/epidemiologia , Bacteriemia/microbiologia , Infecções Comunitárias Adquiridas/epidemiologia , Infecções Comunitárias Adquiridas/microbiologia , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/microbiologia , Atenção à Saúde , Finlândia/epidemiologia , Humanos , Estudos Retrospectivos
20.
PLoS Negl Trop Dis ; 16(9): e0010693, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36084148

RESUMO

INTRODUCTION: Unlike diseases caused by Mycobacterium tuberculosis, M. leprae and M. ulcerans, the epidemiology of pulmonary non-tuberculous mycobacteria (PNTM) has not received due attention in French Guiana. The main objective of the current study was to define the incidence of these PNTM infections: NTM pulmonary diseases (NTM-PD) and casual PNTM isolation (responsible of latent infection or simple colonization). The secondary objectives were to determine species diversity and geographic distribution of these atypical mycobacteria. METHODS: A retrospective observational study (2008-2018) of French Guiana patients with at least one PNTM positive respiratory sample in culture was conducted. Patients were then classified into two groups: casual PNTM isolation or pulmonary disease (NTM-PD), according to clinical, radiological and microbiological criteria defined by the American Thoracic Society / Infectious Disease Society of America (ATS / IDSA) in 2007. RESULTS: 178 patients were included, out of which 147 had casual PNTM isolation and 31 had NTM-PD. Estimated annual incidence rate of respiratory isolates was 6.17 / 100,000 inhabitants per year while that of NTM-PD was 1.07 / 100,000 inhabitants per year. Among the 178 patients, M. avium complex (MAC) was the most frequently isolated pathogen (38%), followed by M. fortuitum then M. abscessus (19% and 6% of cases respectively), the latter two mycobacteria being mainly found in the coastal center region. Concerning NTM-PD, two species were mainly involved: MAC (81%) and M. abscessus (16%). DISCUSSION/CONCLUSION: This is the first study on the epidemiology of PNTM infections in French Guiana. PNTM's incidence looks similar to other contries and metropolitan France and NTM-PD is mostly due to MAC and M.abscessus. Although French Guiana is the French territory with the highest tuberculosis incidence, NTM should not be overlooked.


Assuntos
Pneumopatias , Infecções por Mycobacterium não Tuberculosas , Mycobacterium , Guiana Francesa/epidemiologia , Humanos , Pulmão , Pneumopatias/microbiologia , Infecções por Mycobacterium não Tuberculosas/epidemiologia , Infecções por Mycobacterium não Tuberculosas/microbiologia , Micobactérias não Tuberculosas
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