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1.
Ecol Lett ; 27(6): e14464, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38923281

RESUMEN

Microbiomes are ecosystems, and their stability can impact the health of their hosts. Theory predicts that predators influence ecosystem stability. Phages are key predators of bacteria in microbiomes, but phages are unusual predators because many have lysogenic life cycles. It has been hypothesized that lysogeny can destabilize microbiomes, but lysogeny has no direct analog in classical ecological theory, and no formal theory exists. We studied the stability of computationally simulated microbiomes with different numbers of temperate (lysogenic) and virulent (obligate lytic) phage species. Bacterial populations were more likely to fluctuate over time when there were more temperate phages species. After disturbances, bacterial populations returned to their pre-disturbance densities more slowly when there were more temperate phage species, but cycles engendered by disturbances dampened more slowly when there were more virulent phage species. Our work offers the first formal theory linking lysogeny to microbiome stability.


Asunto(s)
Bacteriófagos , Lisogenia , Microbiota , Bacteriófagos/fisiología , Simulación por Computador , Bacterias/virología , Modelos Biológicos
2.
Environ Microbiol ; 24(12): 5643-5653, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-35920034

RESUMEN

The gut microbiota of social bees is relatively simple and dominated by a set of core taxa found consistently in individuals around the world. Yet, variation remains and can affect host health. We characterized individual- and regional-scale variation in honeybee (Apis mellifera) gut microbiota from 64 colonies in North-West England by sequencing the V4 region of the 16S rRNA gene and asked whether microbiota were influenced by host genotype and landscape composition. We also characterized the genotypes of individual bees and the land cover surrounding each colony. The literature-defined core taxa dominated across the region despite the varied environments. However, there was variation in the relative abundance of core taxa, and colony membership explained much of this variation. Individuals from more genetically diverse colonies had more diverse microbiotas, but individual genetic diversity did not influence gut microbial diversity. There were weak trends for colonies in more similar landscapes to have more similar microbiota, and for bees from more urban landscapes to have less diverse microbiota. To our knowledge, this is the first report for any species that the gut bacterial communities of individuals are influenced by the genotypes of others in the population.


Asunto(s)
Microbioma Gastrointestinal , Microbiota , Abejas , Animales , ARN Ribosómico 16S/genética , Microbioma Gastrointestinal/genética , Bacterias/genética , Variación Genética
4.
Front Psychol ; 12: 654198, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34149539

RESUMEN

Social learning of vocalizations is integral to song inheritance in oscine passerines. However, other factors, such as genetic inheritance and the developmental environment, can also influence song phenotype. The relative contributions of these factors can have a strong influence on song evolution and may affect important evolutionary processes such as speciation. However, relative contributions are well-described only for a few species and are likely to vary with taxonomy. Using archived song data, we examined patterns of song inheritance in a domestic population of Java sparrows (Lonchura oryzivora), some of which had been cross-fostered. Six-hundred and seventy-six songs from 73 birds were segmented and classified into notes and note subtypes (N = 22,972), for which a range of acoustic features were measured. Overall, we found strong evidence for cultural inheritance of song structure and of the acoustic characteristics of notes; sons' song syntax and note composition were similar to that of their social fathers and were not influenced by genetic relatedness. For vocal consistency of note subtypes, a measure of vocal performance, there was no apparent evidence of social or genetic inheritance, but both age and developmental environment influenced consistency. These findings suggest that high learning fidelity of song material, i.e., song structure and note characteristics, could allow novel variants to be preserved and accumulate over generations, with implications for evolution and conservation. However, differences in vocal performance do not show strong links to cultural inheritance, instead potentially serving as condition dependent signals.

5.
Nature ; 590(7847): 561-565, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33627814

RESUMEN

The fundamental building blocks of the proton-quarks and gluons-have been known for decades. However, we still have an incomplete theoretical and experimental understanding of how these particles and their dynamics give rise to the quantum bound state of the proton and its physical properties, such as its spin1. The two up quarks and the single down quark that comprise the proton in the simplest picture account only for a few per cent of the proton mass, the bulk of which is in the form of quark kinetic and potential energy and gluon energy from the strong force2. An essential feature of this force, as described by quantum chromodynamics, is its ability to create matter-antimatter quark pairs inside the proton that exist only for a very short time. Their fleeting existence makes the antimatter quarks within protons difficult to study, but their existence is discernible in reactions in which a matter-antimatter quark pair annihilates. In this picture of quark-antiquark creation by the strong force, the probability distributions as a function of momentum for the presence of up and down antimatter quarks should be nearly identical, given that their masses are very similar and small compared to the mass of the proton3. Here we provide evidence from muon pair production measurements that these distributions are considerably different, with more abundant down antimatter quarks than up antimatter quarks over a wide range of momenta. These results are expected to revive interest in several proposed mechanisms for the origin of this antimatter asymmetry in the proton that had been disfavoured by previous results4, and point to future measurements that can distinguish between these mechanisms.

6.
Conserv Biol ; 35(1): 50-63, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-31989696

RESUMEN

There is a growing recognition that animal behavior can affect wildlife conservation, but there have been few direct studies of animal behavior in conservation programs. However, a great deal of existing behavioral research can be applied in the context of conservation. Research on avian vocalizations provides an excellent example. The conspicuous nature of the vocal behavior of birds makes it a useful tool for monitoring populations and measuring biodiversity, but the importance of vocalizations in conservation goes beyond monitoring. Geographic song variants with population-specific signatures, or dialects, can affect territory formation and mate choice. Dialects are influenced by cultural evolution and natural selection and changes can accumulate even during the timescale of conservation interventions, such as translocations, reintroductions, and ex situ breeding. Information from existing research into avian vocalizations can be used to improve conservation planning and increase the success of interventions. Vocalizations can confer a number of benefits for conservation practitioners through monitoring, providing baseline data on populations and individuals. However, the influence of cultural variation on territory formation, mate choice, and gene flow should be taken into account because cultural differences could create obstacles for conservation programs that bring birds from multiple populations together and so reduce the success of interventions.


Implicaciones y Usos de las Vocalizaciones de Aves para la Conservación de la Planeación Resumen Hay un creciente reconocimiento de que el comportamiento animal puede afectar a la conservación de la fauna, pero ha habido pocos estudios directos del comportamiento animal en los programas de conservación. Sin embargo, una gran cantidad de la investigación existente sobre el comportamiento puede aplicarse en el contexto de la conservación. Las investigaciones sobre las vocalizaciones de aves son un excelente ejemplo. La naturaleza conspicua del comportamiento vocal de las aves hace que sea una herramienta útil para el monitoreo de las poblaciones y las medidas de la biodiversidad, pero la importancia de las vocalizaciones en la conservación va más allá del monitoreo. Las variantes geográficas de canto con firmas específicas para cada población, también conocidas como dialectos, pueden afectar a la formación del territorio y a la elección de pareja. Los dialectos están influenciados por la evolución cultural y la selección natural y los cambios pueden acumularse incluso durante la escala de tiempo de las intervenciones de conservación, como las reubicaciones, las reintroducciones y la reproducción ex situ. La información disponible a partir de las investigaciones existentes sobre las vocalizaciones de aves puede usarse para mejorar la planeación de la conservación e incrementar el éxito de las intervenciones. Las vocalizaciones pueden otorgar un número de beneficios para quienes practican la conservación a través del monitoreo, proporcionando información de la línea base de las poblaciones y los individuos. Sin embargo, la influencia de la variación cultural sobre la formación del territorio, la elección de pareja y el flujo génico deberían considerarse ya que las diferencias culturales podrían crear obstáculos para los programas de conservación que agrupan a aves de diferentes poblaciones y con ello reducen el éxito de las intervenciones.


Asunto(s)
Aves , Conservación de los Recursos Naturales , Animales , Animales Salvajes , Conducta Animal , Biodiversidad
7.
Sci Rep ; 10(1): 8356, 2020 05 20.
Artículo en Inglés | MEDLINE | ID: mdl-32433489

RESUMEN

Pyrazinamide (PZA) is an antibiotic used in first- and second-line tuberculosis treatment regimens. Approximately 50% of multidrug-resistant tuberculosis and over 90% of extensively drug-resistant tuberculosis strains are also PZA resistant. Despite the key role played by PZA, its mechanisms of action are not yet fully understood. It has been postulated that pyrazinoic acid (POA), the hydrolyzed product of PZA, could inhibit trans-translation by binding to Ribosomal protein S1 (RpsA) and competing with tmRNA, the natural cofactor of RpsA. Subsequent data, however, indicate that these early findings resulted from experimental artifact. Hence, in this study we assess the capacity of POA to compete with tmRNA for RpsA. We evaluated RpsA wild type (WT), RpsA ∆A438, and RpsA ∆A438 variants with truncations towards the carboxy terminal end. Interactions were measured using Nuclear Magnetic Resonance spectroscopy (NMR), Isothermal Titration Calorimetry (ITC), Microscale Thermophoresis (MST), and Electrophoretic Mobility Shift Assay (EMSA). We found no measurable binding between POA and RpsA (WT or variants). This suggests that RpsA may not be involved in the mechanism of action of PZA in Mycobacterium tuberculosis, as previously thought. Interactions observed between tmRNA and RpsA WT, RpsA ∆A438, and each of the truncated variants of RpsA ∆A438, are reported.


Asunto(s)
Antituberculosos/farmacología , Proteínas Bacterianas/metabolismo , Farmacorresistencia Bacteriana Múltiple/genética , Mycobacterium tuberculosis/metabolismo , Pirazinamida/análogos & derivados , Proteínas Ribosómicas/metabolismo , Antituberculosos/metabolismo , Antituberculosos/uso terapéutico , Proteínas Bacterianas/genética , Tuberculosis Extensivamente Resistente a Drogas/tratamiento farmacológico , Tuberculosis Extensivamente Resistente a Drogas/microbiología , Humanos , Mutación , Mycobacterium tuberculosis/efectos de los fármacos , Mycobacterium tuberculosis/genética , Pirazinamida/metabolismo , Pirazinamida/farmacología , Pirazinamida/uso terapéutico , ARN Bacteriano/metabolismo , Proteínas Ribosómicas/genética
9.
Diabet Med ; 37(9): 1519-1527, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32181918

RESUMEN

AIM: To determine whether intermediate hyperglycaemia, defined by fasting plasma glucose and HbA1c criteria, is associated with mortality in a 10-year cohort of people in a Latin American country. METHODS: Analysis of the PERU MIGRANT Study was conducted in three different population groups (rural, rural-to-urban migrant, and urban). The baseline assessment was conducted in 2007/2008, with follow-up assessment in 2018. The outcome was all-cause mortality, and the exposure was intermediate hyperglycaemia, using three definitions: (1) impaired fasting glucose, defined according to American Diabetes Association criteria [fasting plasma glucose 5.6-6.9 mmol/l (100-125 mg/dl)]; (2) intermediate hyperglycaemia defined according to American Diabetes Association criteria [HbA1c levels 39-46 mmol/mol (5.7-6.4%)]; and (3) intermediate hyperglycaemia defined according to the International Expert Committee criteria [HbA1c levels 42-46 mmol/mol (6.0-6.4%)]. Crude and adjusted hazard ratios and 95% CIs were estimated using Cox proportional hazard models. RESULTS: At baseline, the mean (sd) age of the study population was 47.8 (11.9) years and 52.5% of the cohort were women. The study cohort was divided into population groups as follows: 207 people (20.0%) in the rural population group, 583 (59.7%) in the rural-to-urban migrant group and 198 (20.3%) in the urban population group. The prevalence of intermediate hyperglycaemia was: 6%, 12.9% and 38.5% according to the American Diabetes Association impaired fasting glucose definition, the International Expert Committee HbA1c -based definition and the American Diabetes Association HbA1c -based definition, respectively, and the mortality rate after 10 years was 63/976 (7%). Intermediate hyperglycaemia was associated with all-cause mortality using the HbA1c -based definitions in the crude models [hazard ratios 2.82 (95% CI 1.59-4.99) according to the American Diabetes Association and 2.92 (95% CI 1.62-5.28) according to the International Expert Committee], whereas American Diabetes Association-defined impaired fasting glucose was not [hazard ratio 0.84 (95% CI 0.26-2.68)]. In the adjusted model, however, only the American Diabetes Association HbA1c -based definition was associated with all-cause mortality [hazard ratio 1.91 (95% CI 1.03-3.53)], whereas the International Expert Committee HbA1c -based and American Diabetes Association impaired fasting glucose-based definitions were not [hazard ratios 1.42 (95% CI 0.75-2.68) and 1.09 (95% CI 0.33-3.63), respectively]. CONCLUSIONS: Intermediate hyperglycaemia defined using the American Diabetes Association HbA1c criteria was associated with an elevated mortality rate after 10 years in a cohort from Peru. HbA1c appears to be a factor associated with mortality in this Peruvian population.


Asunto(s)
Glucemia/metabolismo , Intolerancia a la Glucosa/metabolismo , Hemoglobina Glucada/metabolismo , Hiperglucemia/metabolismo , Mortalidad , Estado Prediabético/metabolismo , Adulto , Causas de Muerte , Femenino , Recursos en Salud , Humanos , Masculino , Persona de Mediana Edad , Perú , Modelos de Riesgos Proporcionales , Población Rural/estadística & datos numéricos , Migrantes/estadística & datos numéricos , Población Urbana/estadística & datos numéricos
10.
Proc Biol Sci ; 287(1921): 20192770, 2020 02 26.
Artículo en Inglés | MEDLINE | ID: mdl-32070258

RESUMEN

Social learning occurs when animals acquire knowledge or skills by observing or interacting with others and is the fundamental building block of culture. Within populations, some individuals use social learning more frequently than others, but why social learning phenotypes differ among individuals is poorly understood. We modelled the evolution of social learning frequency in a system where foragers compete for resources, and there are many different foraging options to learn about. Social learning phenotypes diverged when some options offered much better rewards than others and expected rewards changed moderately quickly over time. When options offered similar rewards or when rewards changed slowly, a single social learning phenotype evolved. This held for fixed and simple conditional social learning rules. Sufficiently complex conditional social learning rules prevented the divergence of social learning phenotypes under all conditions. Our results explain how competition can promote the divergence of social learning phenotypes.


Asunto(s)
Evolución Biológica , Fenotipo , Animales , Conducta Apetitiva , Simulación por Computador , Aprendizaje , Conducta Social , Aprendizaje Social
11.
Sci Rep ; 9(1): 15402, 2019 10 28.
Artículo en Inglés | MEDLINE | ID: mdl-31659217

RESUMEN

Left-handedness is a costly, sexually dimorphic trait found at low frequencies in all human populations. How the handedness polymorphism is maintained is unclear. The fighting hypothesis argues that left-handed men have a negative frequency-dependent advantage in violent intrasexual competition giving them a selective advantage. In support of this, many studies have found that left-handed men are overrepresented among modern professional fighters, but studies typically find no difference in fighting success between left and right-handed fighters. We studied over 13,800 professional boxers and mixed martial artists of varying abilities in three of the largest samples to test this hypothesis to date, finding robust evidence that left-handed fighters have greater fighting success. This held for both male and female fighters, and for both percentage of fights won and an objective measure of fighting ability. We replicated previous results showing that left-handed fighters are strongly overrepresented in professional combat sports, but left-handed fighters did not show greater variance in fighting ability, a hypothesis suggested in previous studies. Overall we find strong evidence consistent with the fighting hypothesis.


Asunto(s)
Brazo/fisiología , Rendimiento Atlético/fisiología , Boxeo/fisiología , Lateralidad Funcional , Adulto , Femenino , Humanos , Masculino
12.
R Soc Open Sci ; 6(7): 182084, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31417699

RESUMEN

Individuals vary in their propensity to use social learning, the engine of cultural evolution, to acquire information about their environment. The causes of those differences, however, remain largely unclear. Using an agent-based model, we tested the hypothesis that as a result of reproductive skew differences in energetic requirements for reproduction affect the value of social information. We found that social learning is associated with lower variance in yield and is more likely to evolve in risk-averse low-skew populations than in high-skew populations. Reproductive skew may also result in sex differences in social information use, as empirical data suggest that females are often more risk-averse than males. To explore how risk may affect sex differences in learning strategies, we simulated learning in sexually reproducing populations where one sex experiences more reproductive skew than the other. When both sexes compete for the same resources, they tend to adopt extreme strategies: the sex with greater reproductive skew approaches pure individual learning and the other approaches pure social learning. These results provide insight into the conditions that promote individual and species level variation in social learning and so may affect cultural evolution.

13.
Phys Rev Lett ; 122(2): 022002, 2019 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-30720291

RESUMEN

The Spin Asymmetries of the Nucleon Experiment measured two double spin asymmetries using a polarized proton target and polarized electron beam at two beam energies, 4.7 and 5.9 GeV. A large-acceptance open-configuration detector package identified scattered electrons at 40° and covered a wide range in Bjorken x (0.3

14.
Int J Tuberc Lung Dis ; 23(12): 1286-1292, 2019 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-31931913

RESUMEN

BACKGROUND: It is very difficult to observe tuberculosis (TB) transmission chains and thus, identify superspreaders. We investigate cough duration as a proxy measure of transmission to assess the presence of potential TB superspreaders.DESIGN: We analyzed six studies from China, Peru, The Gambia and Uganda, and determined the distribution of cough duration and compared it with several theoretical distributions. To determine factors associated with cough duration, we used linear regression and boosted regression trees to examine the predictive power of patient, clinical and environmental characteristics.RESULTS: We found within-study heterogeneity in cough duration and strong similarities across studies. Approximately 20% of patients contributed 50% of total cough days, and around 50% of patients contributed 80% of total cough days. The cough duration distribution suggested an initially increasing, and subsequently, decreasing hazard of diagnosis. While some of the exposure variables showed statistically significant associations with cough duration, none of them had a strong effect. Multivariate analyses of different model types did not produce a model that had good predictive power.CONCLUSION: We found consistent evidence for the presence of supercoughers, but no characteristics predictive of such individuals.


Asunto(s)
Tos/fisiopatología , Tuberculosis Pulmonar/epidemiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , China/epidemiología , Estudios de Cohortes , Tos/etiología , Femenino , Gambia/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Perú/epidemiología , Tuberculosis Pulmonar/complicaciones , Tuberculosis Pulmonar/transmisión , Uganda/epidemiología , Adulto Joven
15.
Environ Microbiol Rep ; 11(2): 206-214, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30507071

RESUMEN

The species of the genus Saccharomyces are commonly inhabiting tree bark and the surrounding soil, but their abundance have likely been underestimated due to biases in culturing methods. Metagenomic studies have so far been unable to detect Saccharomyces species in wild environments. Here, we sequenced the mycobiome of soils surrounding different trees at various altitudes in the Italian Alps. To survey for yeasts species belonging to Saccharomyces genus rather than other fungal species, we performed a selectivity step involving the isolation of the internal transcribed spacer (ITS) region that is specific to this yeast group. Reads mapping to Saccharomyces species were detected in all soil samples, including reads for S. mikatae and for S. eubayanus. ITS1 alignment of the S. cerevisiae, S. paradoxus and S. kudriavzevii sequences showed up to three base pair polymorphisms with other known strains, indicating possible new lineages. Basidiomycetous fungi were still the dominant species, compared to the Ascomycota, but the selectivity step allowed for the first time the detection and study of the biodiversity of the Saccharomyces species in their natural environment.


Asunto(s)
Biodiversidad , Metagenómica/métodos , Saccharomyces/genética , Microbiología del Suelo , ADN de Hongos/genética , ADN Espaciador Ribosómico/genética , Genoma Fúngico/genética , Italia , Saccharomyces/clasificación , Saccharomyces/aislamiento & purificación , Saccharomyces cerevisiae/clasificación , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/aislamiento & purificación , Análisis de Secuencia de ADN , Árboles
16.
Am Nat ; 192(3): 332-346, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-30125229

RESUMEN

There is growing evidence that speciation can occur between populations that are not geographically isolated. The emergence of assortative mating is believed to be critical to this process, but how assortative mating arises in diverging populations is poorly understood. The wolf spider genus Schizocosa has become a model system for studying mechanisms of assortative mating. We conducted a series of experiments to identify the factors that control mate pair formation in a Schizocosa population that includes both ornamented and nonornamented males. We show that the population also includes two previously unrecognized female phenotypes. One female phenotype mates mostly or exclusively with ornamented males, and the other mates mostly or exclusively with unornamented males. Assortative mating within these groups is maintained by differences in maturation time, microhabitat use, and female mate preference. We conclude that the population is not a single species, as previously believed, but rather an incipient species pair with multiple overlapping mechanisms of reproductive isolation. The identification of a new incipient species pair in the well-studied and rapidly speciating Schizocosa clade presents new opportunities for the study of speciation without geographic isolation.


Asunto(s)
Especiación Genética , Preferencia en el Apareamiento Animal , Aislamiento Reproductivo , Arañas/genética , Animales , Ecosistema , Femenino , Masculino , Arañas/crecimiento & desarrollo
17.
Int J Tuberc Lung Dis ; 22(6): 622-627, 2018 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-29862945

RESUMEN

SETTING: There remains a lack of effective and inexpensive diagnostic tools for active tuberculosis (TB) disease. Testing immune responses to proteins secreted by Mycobacterium tuberculosis, such as MPT64, may be a diagnostic option. OBJECTIVE: To evaluate the sensitivity and specificity of a patch test using MPT64 for the diagnosis of active TB disease. DESIGN: This randomised, double-blind, placebo-controlled, prospective study in Lima, Peru, involved 55 healthy controls and 457 symptomatic individuals referred for routine TB testing by the National TB Control Programme. All subjects underwent a comprehensive diagnostic workup, and received an active patch on one arm and a placebo patch on the opposite arm, which were read after 4 days. RESULTS: Eighty-one (18%) of the symptomatic participants were classified as having definite TB, while an additional 98 (21%) had probable TB. The patch tests performed the same in both groups, with a sensitivity of 27% and specificity of 74%. The area under the receiver operating characteristic curve was 0.495 (95%CI 0.425-0.565). CONCLUSIONS: Contrary to existing literature, the MPT64 patch was not sensitive and specific to detect active TB. Given the potential of the test, understanding possible differences in the protein source or underlying genetic factors should be explored further.


Asunto(s)
Tamizaje Masivo/métodos , Mycobacterium tuberculosis/aislamiento & purificación , Pruebas del Parche/métodos , Tuberculosis Pulmonar/diagnóstico , Adulto , Método Doble Ciego , Femenino , Humanos , Masculino , Perú/epidemiología , Estudios Prospectivos , Curva ROC , Sensibilidad y Especificidad , Tuberculosis Pulmonar/epidemiología , Adulto Joven
18.
Zoonoses Public Health ; 65(5): 528-539, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29602269

RESUMEN

Interspecies transmission of pathogens is an unfrequent but naturally occurring event and human activities may favour opportunities not previously reported. Reassortment of zoonotic pathogens like influenza A virus can result from these activities. Recently, swine and birds have played a central role as "mixing vessels" for epidemic and pandemic events related to strains like H1N1 and H5N1. Unsafe practices in poultry markets and swine farms can lead to interspecies transmission, favouring the emergence of novel strains. Thus, understanding practices that lead to interspecies interactions is crucial. This qualitative study aimed to evaluate poultry processing practices in formal and informal markets and the use of leftovers by swine farmers in three Peruvian cities: Lima (capital), Tumbes (coastal) and Tarapoto (jungle). We conducted 80 direct observations at formal and informal markets and interviewed 15 swine farmers. Processors slaughter and pluck chickens and vendors and/or processors eviscerate chickens. Food safety and hygiene practices were suboptimal or absent, although some heterogeneity was observed between cities and chicken vendors versus processors. Both vendors (76%) and processors (100%) sold the chicken viscera leftovers to swine farmers, representing the main source of chicken viscera for swine farms (53%). Swine farmers fed the chicken viscera to their swine. Chicken viscera cooking times varied widely and were insufficient in some cases. Non-abattoired poultry leads to the sale of poultry leftovers to small-scale swine farms, resulting in indirect but frequent interspecies contacts that can lead to interspecies transmission of bacterial pathogens or the reassortment of influenza A viruses. These interactions are exacerbated by suboptimal safety and hygiene conditions. People involved in these activities constitute an at-risk population who could play a central role in preventing the transmission of pathogens between species. Educational interventions on hygiene and food safety practices will be important for reducing the risk of interspecies influenza transmission.


Asunto(s)
Virus de la Influenza A/aislamiento & purificación , Carne/microbiología , Infecciones por Orthomyxoviridae/veterinaria , Alimentación Animal , Animales , Pollos , Manipulación de Alimentos , Humanos , Infecciones por Orthomyxoviridae/epidemiología , Infecciones por Orthomyxoviridae/transmisión , Infecciones por Orthomyxoviridae/virología , Perú/epidemiología , Enfermedades de las Aves de Corral/epidemiología , Enfermedades de las Aves de Corral/transmisión , Enfermedades de las Aves de Corral/virología , Factores de Riesgo , Porcinos , Enfermedades de los Porcinos/epidemiología , Enfermedades de los Porcinos/transmisión , Enfermedades de los Porcinos/virología , Zoonosis
19.
Artículo en Inglés | MEDLINE | ID: mdl-29276619

RESUMEN

Sleep difficulties and short sleep duration have been associated with hypertension. Though body mass index (BMI) may be a mediator variable, the mediation effect has not been defined. We aimed to assess the association between sleep duration and sleep difficulties with hypertension, to determine if BMI is a mediator variable, and to quantify the mediation effect. We conducted a mediation analysis and calculated prevalence ratios with 95% confidence intervals. The exposure variables were sleep duration and sleep difficulties, and the outcome was hypertension. Sleep difficulties were statistically significantly associated with a 43% higher prevalence of hypertension in multivariable analyses; results were not statistically significant for sleep duration. In these analyses, and in sex-specific subgroup analyses, we found no strong evidence that BMI mediated the association between sleep indices and risk of hypertension. Our findings suggest that BMI does not appear to mediate the association between sleep patterns and hypertension. These results highlight the need to further study the mechanisms underlying the relationship between sleep patterns and cardiovascular risk factors.

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