696 research outputs found
Atypical Non-H2S-Producing Monophasic Salmonella Typhimurium ST3478 Strains from Chicken Meat at Processing Stage Are Adapted to Diverse Stresses
Poultry products are still an important cause of Salmonella infections worldwide, with an increasingly reported expansion of less-frequent serotypes or atypical strains that are frequently multidrug-resistant. Nevertheless, the ability of Salmonella to survive antimicrobials promoted in the context of antibiotic reducing/replacing and farming rethinking (e.g., organic acids and copper in feed/biocides) has been scarcely explored. We investigated Salmonella occurrence (conventional and molecular assays) among chicken meat at the processing stage (n = 53 batches/29 farms) and characterized their tolerance to diverse stress factors (antibiotics, copper, acid pH, and peracetic acid). Whole-genome sequencing was used to assess adaptive features and to perform comparative analysis. We found a low Salmonella occurrence (4%) and identified S. Enteritidis/ST11 plus atypical non-H2S-producing S. 1,4,[5],12:i:-/ST3478. The ST3478 presented the ability to grow under diverse stresses (antibiotics, copper, and acid-pH). Comparative genomics among ST3478 isolates showed similar antibiotic/metal resistance gene repertoires and identical nonsense phsA thiosulfate reductase mutations (related to H2S-negative phenotype), besides their close phylogenetic relationship by cgMLST and SNPs. This study alerts for the ongoing national and international spread of an emerging monophasic Salmonella Typhimurium clonal lineage with an enlarged ability to survive to antimicrobials/biocides commonly used in poultry production, being unnoticed by conventional Salmonella detection approaches due to an atypical non-H2S-producing phenotype
General bounds on non-standard neutrino interactions
We derive model-independent bounds on production and detection non-standard
neutrino interactions (NSI). We find that the constraints for NSI parameters
are around O(10^{-2}) to O(10^{-1}). Furthermore, we review and update the
constraints on matter NSI. We conclude that the bounds on production and
detection NSI are generally one order of magnitude stronger than their matter
counterparts.Comment: 18 pages, revtex4, 1 axodraw figure. Minor changes, matches published
versio
Occupational Exposure to Mycotoxins in Swine Production: Environmental and Biological Monitoring Approaches
Free PMC article: https://www.ncbi.nlm.nih.gov/pmc/articles/pmid/30717100/The authors are grateful to the swine farms employers and workers that collaborate in
this research project. R.A. and C.M. are grateful to INSA and to CESAM (UID/AMB/50017/2013) through
national funds (FCT), and the co-funding by the Fundo Europeu de Desenvolvimento Regional (FEDER)
(POCI-01-0145-FEDER-00763), within the PT2020 Partnership Agreement and Compete 2020.Swine production workers are exposed simultaneously to multiple contaminants. Occupational exposure to aflatoxin B1 (AFB1) in Portuguese swine production farms has already been reported. However, besides AFB1, data regarding fungal contamination showed that exposure to other mycotoxins could be expected in this setting. The present study aimed to characterize the occupational exposure to multiple mycotoxins of swine production workers. To provide a broad view on the burden of contamination by mycotoxins and the workers’ exposure, biological (urine) samples from workers (n = 25) and 38 environmental samples (air samples, n = 23; litter samples, n = 5; feed samples, n = 10) were collected. The mycotoxins biomarkers detected in the urine samples of the workers group were the deoxynivalenol-glucuronic acid conjugate (60%), aflatoxin M1 (16%), enniatin B (4%), citrinin (8%), dihydrocitrinone (12%) and ochratoxin A (80%). Results of the control group followed the same pattern, but in general with a lower number of quantifiable results (<LOQ). Besides air samples, all the other environmental samples collected presented high and diverse contamination, and deoxynivalenol (DON), like in the biomonitoring results, was the most prominent mycotoxin. The results demonstrate that the occupational environment is adding and contributing to the workers’ total exposure to mycotoxins, particularly in the case of DON. This was confirmed by the biomonitoring data and the high contamination found in feed and litter samples. Furthermore, the followed multi-biomarker approach allowed to conclude that workers and general population are exposed to several mycotoxins simultaneously. Moreover, occupational exposure is probably described as being intermittent and with very high concentrations for short durations. This should be reflected in the risk assessment process.This research was funded by Instituto Politécnico de Lisboa, Lisbon, Portugal: Project “Bacterial
Bioburden assessment in the context of occupational exposure and animal health of swine productions
(IPL/2016/BBIOR_ESTeSL)” and also by FCT—Fundação para Ciência e Tecnologia: Project “EXPOsE –
Establishing protocols to assess occupational exposure to microbiota in clinical settings (02/SAICT/2016 – Project nº 23222)”.info:eu-repo/semantics/publishedVersio
Low-Protein Diets, Malnutrition, and Bone Metabolism in Chronic Kidney Disease
This article belongs to the Special Issue The Role of Dietary Patterns in Malnutrition – Relevance of Body Weight upon Non-communicable Diseases.Chronic kidney disease (CKD) has a high prevalence worldwide, with increasing incidence in low- and middle-income countries, and is associated with high morbidity and mortality, particularly from cardiovascular disease. Protein-restricted diets are one of the most widely used non-pharmacological approaches to slow the progression of CKD and prevent associated metabolic abnormalities. However, some concerns have been raised about the long-term safety of these diets, particularly with regard to patients’ nutritional status and bone and mineral disorders. Therefore, the aim of this article is to review the most recent scientific evidence on the relevance of using protein-restricted diets (with or without keto-analogue supplementation) and, in particular, their relationships with malnutrition and mineral and bone disorders in people with CKD without kidney replacement therapies. Although protein-restricted diets, especially when supplemented with keto-analogues and highly personalized and monitored, do not appear to be associated with malnutrition, research on their effects on bone and mineral disorders is scarce, deserving further investigation.info:eu-repo/semantics/publishedVersio
Loop bounds on non-standard neutrino interactions
We reconsider the bounds on non-standard neutrino interactions with matter
which can be derived by constraining the four-charged-lepton operators induced
at the loop level. We find that these bounds are model dependent. Naturalness
arguments can lead to much stronger constraints than those presented in
previous studies, while no completely model-independent bounds can be derived.
We will illustrate how large loop-contributions to four-charged-lepton
operators are induced within a particular model that realizes gauge invariant
non-standard interactions and discuss conditions to avoid these bounds. These
considerations mainly affect the constraint on the
non-standard coupling strength \eps_{e\mu}, which is lost. The only
model-independent constraints that can be derived are .
However, significant cancellations are required in order to saturate this
bound.Comment: Minor changes, version to be published in JHEP. 17 pages, 3 Axodraw
figures, REVTeX
Fluid flow and structural numerical analysis of a cerebral aneurysm model
Intracranial aneurysms (IA) are dilations of the cerebral arteries and, in most cases, have no
symptoms. However, it is a very serious pathology, with a high mortality rate after rupture. Several
studies have been focused only on the hemodynamics of the flow within the IA. However, besides
the effect of the flow, the development and rupture of the IA are also associated with a combination
of other factors such as the wall mechanical behavior. Thus, the objective of this work was to
analyze, in addition to the flow behavior, the biomechanical behavior of the aneurysm wall. For
this, CFD simulations were performed for different Reynolds numbers (1, 100, 500 and 1000) and
for two different rheological models (Newtonian and Carreau). Subsequently, the pressure values of
the fluid simulations were exported to the structural simulations in order to qualitatively observe
the deformations, strains, normal stresses and shear stress generated in the channel wall. For the
structural simulations, a hyperelastic constitutive model (5-parameter Mooney–Rivlin) was used. The
results show that with the increase in the Reynolds number (Re), the recirculation phenomenon is
more pronounced, which is not seen for Re = 1. The higher the Re, the higher the strain, displacement,
normal and shear stresses values.The authors acknowledge the financial support from the project EXPL/EME-EME/0732/2021,
funded by the NORTE 2020 Portugal Regional Operational Programme, under the PORTUGAL
2020 Partnership Agreement, through the European Regional Development Fund (FEDER) and
by Fundação para a Ciência e Tecnologia (FCT). This work was also supported by Fundação para
a Ciência e a Tecnologia (FCT) under the strategic grants UIDB/04077/2020, UIDB/04436/2020,
UIDB/00319/2020 and UIDB/00532/2020. Andrews Souza and Violeta Carvalho also acknowledge
the financial support by FCT through the individual research grants 2021.07961.BD and
UI/BD/151028/2021, respectively.info:eu-repo/semantics/publishedVersio
Tolerance to Abiotic Factors of Microsclerotia and Mycelial Pellets From Metarhizium robertsii, and Molecular and Ultrastructural Changes During Microsclerotial Differentiation
Metarhizium spp. fungi are able to produce resistant structures termed microsclerotia, formed by compacted and melanized threads of hyphae. These propagules are tolerant to desiccation and produce infective conidia, thus they are promising candidates to use in biological control programs. In this study, we investigated the tolerance to both UV-B radiation and heat of microsclerotia of M. robertsii strain ARSEF 2575. We also adapted the liquid medium and culture conditions to obtain mycelial pellets from the same isolate in order to compare these characteristics between both types of propagules. We followed the peroxisome biogenesis and studied the oxidative stress during differentiation from conidia to microsclerotia by transmission electron microscopy after staining with a peroxidase activity marker, and by the expression pattern of genes potentially involved in these processes. We found that despite their twice smaller size, microsclerotia exhibited higher dry biomass, yield, and conidial productivity than mycelial pellets, both with and without UV-B and heat stresses.. From the sixteen genes measured, we found an induction after 96-h differentiation in the oxidative stress marker genes MrcatA, MrcatP, and Mrgpx, the peroxisome biogenesis factors Mrpex5 and Mrpex14/17, and the photoprotection genes Mrlac1, Mrlac2, and Mrlac3. We concluded that an oxidative stress scenario is induced during microsclerotia differentiation in M. robertsii, and confirmed that due to its tolerance to desiccation, heat, and UV-B, this fungal structure could be an excellent candidate for use in biological control of pests under tropical and subtropical climates where heat and UV radiation are detrimental to entomopathogenic fungi survival and persistence.Fil: Paixão, Flávia R. S.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Bioquímicas de La Plata "Prof. Dr. Rodolfo R. Brenner". Universidad Nacional de la Plata. Facultad de Ciencias Médicas. Instituto de Investigaciones Bioquímicas de La Plata "Prof. Dr. Rodolfo R. Brenner"; ArgentinaFil: Huarte Bonnet, Carla. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Bioquímicas de La Plata "Prof. Dr. Rodolfo R. Brenner". Universidad Nacional de la Plata. Facultad de Ciencias Médicas. Instituto de Investigaciones Bioquímicas de La Plata "Prof. Dr. Rodolfo R. Brenner"; ArgentinaFil: Ribeiro-Silva, Cárita de S.. Universidade Federal de Goias. Instituto de Patologia Tropical E Saude Publica.; BrasilFil: Mascarin, Gabriel M.. Empresa Brasilera de Pesquisa Agropecuaria.; BrasilFil: Fernandes, Éverton. Universidade Federal de Goias. Instituto de Patologia Tropical E Saude Publica.; BrasilFil: Pedrini, Nicolás. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Bioquímicas de La Plata "Prof. Dr. Rodolfo R. Brenner". Universidad Nacional de la Plata. Facultad de Ciencias Médicas. Instituto de Investigaciones Bioquímicas de La Plata "Prof. Dr. Rodolfo R. Brenner"; Argentin
Semi-pelagic Longline and Trammel Net Elasmobranch Catches in Southern Portugal: Catch Composition, Catch Rates and Discards
In Portugal, elasmobranch landings have decreased substantially in recent years. In this work,
elasmobranch catches in semi-pelagic longlines (1997 and 1998) were compared with those in trammel
nets (2000) in the Algarve, southern Portugal areas. In the semi-pelagic longline fi shery, 7 elasmobranch
species represented 33.4% (2 185 specimens) of the total fi sh catches. Among the elasmobranch species,
the most abundant were Galeus melastomus (63.3%), Etmopterus pusillus (21.7%) and Scyliorhinus
canicula (14.2%). Most of these elasmobranchs were discarded (68.3% in total). In the trammel net
fi shery, 16 different elasmobranch species represented 4.3% (597 specimens) of total fi sh catches and
the most important species were Raja undulata (43.6%) and S. canicula (10.2%). The majority of
the elasmobranchs caught in trammel nets had commercial value, and only 5.4% were discarded. In
both fi sheries, intra-specifi c catch rates varied with depth. Length-frequency distributions for the only
species with relatively high catches in both fi sheries, S. canicula, showed that, in general, trammel
nets catch larger specimens and in a narrower length range than do longlines.info:eu-repo/semantics/publishedVersio
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