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1.
J Gerontol Nurs ; 49(7): 25-30, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37379050

RESUMO

Rural older adults residing in assisted living (AL) (herein referred to as residents) have limited access to health care for urgent and chronic management of diseases. The current project aimed to assess rural residents, families, and staff satisfaction with the Nurse Practitioner (NP) Offsite Visit Program. Residents and their families were asked to complete the NP Satisfaction Survey. The survey comprised three subscales (satisfaction, communication, and accessibility) and measured residents' and families' satisfaction. AL staff attended a 1-hour focus interview. Mean survey scores were 81.5 for satisfaction, 26.4 for communication, and 16.9 for accessibility subscales. Focus interview themes included Care Coordination, Prevention of Acute Care Utilization, and Access to Care. Findings suggest that residents, families, and site staff believe the NP Offsite Visit Program was beneficial and improved care coordination between residents and the provider team. The next step is to evaluate the program's impact on residents' health outcomes and further evaluate the Offsite team membership. [Journal of Gerontological Nursing, 49(7), 25-30.].


Assuntos
Atenção à Saúde , Profissionais de Enfermagem , Humanos , Idoso
2.
Rev Sci Tech ; 41(1): 82-90, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35925634

RESUMO

Drosophila melanogaster has been a model organism for experimental research for more than a century, and the knowledge and associated genetic technologies accumulated around this species make it extremely important to contemporary biomedical research. A large international community of highly collaborative scientists investigate a remarkable diversity of biological problems using genetically characterised strains of Drosophila, and frequently exchange these strains across borders. Despite its importance to the study of fundamental biological processes and human disease-related cellular mechanisms, and the fact that it presents minimal health, agricultural or environmental risks, Drosophila can be difficult to import. The authors argue that streamlined regulations and practices would benefit biomedical research by lowering costs and increasing efficiencies.


Drosophila melanogaster sert d'organisme modèle pour la recherche expérimentale depuis plus d'un siècle, aboutissant à une somme de connaissances sur cette espèce et sur les technologies génétiques qui lui sont associées qui la rendent extrêmement importante pour la recherche biomédicale contemporaine. Aujourd'hui, une vaste communauté internationale de chercheurs dotés d'une culture élevée de la collaboration étudie un nombre impressionnant de problèmes biologiques en utilisant des souches de drosophile caractérisées sur le plan génétique, ce qui conduit à un partage fréquent de ces souches au-delà des frontières nationales. Or, il est parfois difficile d'importer des drosophiles, en dépit de l'importance de cette espèce pour l'étude des processus biologiques fondamentaux et des mécanismes cellulaires liés aux maladies humaines, et du risque minime qu'elle représente pour la santé, l'agriculture ou l'environnement. Les auteurs estiment qu'une rationalisation des réglementations et des pratiques serait bénéfique pour la recherche biomédicale car elle permettrait de réduire les coüts et de gagner en efficacité.


Drosophila melanogaster es un organismo modelo para las investigaciones experimentales desde hace más de un siglo. El acervo de conocimientos y las correspondientes tecnologías genéticas que se han ido acumulando en relación con esta especie hacen de ella un elemento de suma importancia para la actual investigación biomédica. Hay una gran comunidad internacional de científicos que, trabajando en estrecha colaboración, investigan muy diversos problemas biológicos sirviéndose de cepas de Drosophila genéticamente caracterizadas, para lo cual intercambian a menudo estas cepas de uno a otro país. Pese a su importancia para el estudio de procesos biológicos fundamentales y de mecanismos celulares ligados a enfermedades humanas, y pese a que los riesgos sanitarios, agrícolas o ambientales que entraña son mínimos, la importación de Drosophila puede resultar dificultosa. Los autores postulan que la simplificación de procesos y reglamentos sería beneficiosa para la investigación biomédica, pues reduciría costos y permitiría ganar en eficiencia.


Assuntos
Pesquisa Biomédica , Drosophila melanogaster , Animais , Drosophila melanogaster/genética , Humanos
3.
Rev Sci Tech ; 41(1): 219-227, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35925619

RESUMO

A network of scientists involved in shipment of live insects has met and generated a series of articles on issues related to live insect transport. The network is diverse, covering large-scale commercial interests, government operated areawide control programmes, biomedical research and many smaller applications, in research, education and private uses. Many insect species have a record of safe transport, pose minimal risks and are shipped frequently between countries. The routine shipments of the most frequently used insect model organism for biomedical research, Drosophila melanogaster, is an example. Successful large scale shipments from commercial biocontrol and pollinator suppliers also demonstrate precedents for low-risk shipment categories, delivered in large volumes to high quality standards. Decision makers need access to more information (publications or official papers) that details actual risks from the insects themselves or their possible contaminants, and should propose proportionate levels of management. There may be harm to source environments when insects are collected directly from the wild, and there may be harm to receiving environments. Several risk frameworks include insects and various international coordinating bodies, with experience of guidance on relevant risks, exist. All stakeholders would benefit from an integrated overview of guidance for insect shipping, with reference to types of risk and categories of magnitude, without trying for a single approach requiring universal agreement. Proposals for managing uncertainty and lack of data for smaller or infrequent shipments, for example, must not disrupt trade in large volumes of live insects, which are already supporting strategic objectives in several sectors.


À l'occasion d'une réunion d'experts, un réseau de chercheurs travaillant sur l'expédition d'insectes vivants a produit un ensemble d'articles traitant des questions liées au transport des insectes vivants. Ce réseau est diversifié et représente un large éventail d'intérêts privés et de programmes de lutte biologique à grande échelle menés par les pouvoirs publics, en plus du secteur de la recherche biomédicale et de nombreux acteurs intervenant dans des applications de plus petite envergure relevant de la recherche, de l'enseignement ou du secteur privé. Un grand nombre d'espèces d'insectes sont transportées en toute sécurité avec un niveau de risque minimal, y compris lors des fréquentes expéditions internationales. Un exemple de ces expéditions régulières concerne l'espèce la plus utilisée par la recherche biomédicale en tant qu'organisme modèle, à savoir Drosophila melanogaster. Les exemples réussis d'expéditions à grande échelle provenant de fournisseurs d'agents de lutte biologique et de pollinisateurs produits par le secteur privé offrent également un relevé documenté des diverses catégories d'expéditions à faible risque pour des livraisons d'insectes vivants en grandes quantités et répondant à des normes de qualité élevées. Les décideurs politiques devraient pouvoir accéder à plus d'informations (à travers des publications ou des articles officiels) décrivant en détail les risques réels associés aux insectes eux-mêmes ou à leurs contaminants éventuels, et proposer en connaissance de cause des niveaux de gestion proportionnels à ces risques. La récolte d'insectes prélevés directement de la nature peut être dommageable aussi bien pour les environnements source que pour ceux de destination. Plusieurs cadres fondés sur le risque intègrent désormais les insectes dans leurs directives. Par ailleurs, nombre d'organismes internationaux de coordination ont acquis une expérience dans l'élaboration de lignes directrices face à ces risques. Il serait bénéfique pour toutes les parties prenantes de disposer d'une vue d'ensemble intégrée des directives applicables aux expéditions d'insectes, qui recense les différents types de risque et leurs ordres de grandeur sans se prononcer sur une approche unique qui nécessiterait une adhésion universelle. Ni les propositions visant à gérer l'incertitude ni l'insuffisance des données disponibles sur les expéditions d'insectes en petits nombres ou occasionnelles ne doivent perturber les échanges commerciaux d'insectes vivants en grandes quantités, échanges qui participent aujourd'hui aux objectifs stratégiques de nombreux secteurs.


Una red de científicos relacionados de un modo u otro con el transporte de insectos vivos mantuvo un encuentro y generó una serie de artículos en torno a la cuestión. En la red, muy heterogénea, convergen desde intereses comerciales de gran calado hasta programas públicos de lucha biológica en grandes territorios, pasando por la investigación biomédica y por numerosas aplicaciones de menor dimensión en ámbitos como la investigación, la enseñanza u otros usos privados. Muchas especies de insectos cuentan con un buen historial de seguridad en el transporte, presentan un riesgo mínimo y son expedidas a menudo de un país a otro. Buen ejemplo de ello son los envíos sistemáticos de ejemplares de Drosophila melanogaster, que es el insecto utilizado con más frecuencia como organismo modelo en la investigación biomédica. Otro precedente de envíos voluminosos cuyo transporte y entrega se ajusta a los más exigentes criterios de calidad lo sientan las remesas de grandes cantidades de polinizadores y agentes de control biológico remitidos por proveedores comerciales. Los responsables de adoptar decisiones deben disponer de más y más detallada información (publicaciones o documentos oficiales) sobre los riesgos reales derivados de los propios insectos o sus posibles contaminantes para proponer a partir de ahí medidas de gestión proporcionadas. Los perjuicios ambientales pueden darse tanto en origen (cuando hay captura salvaje de insectos, o sea recolección directa en el medio) como en destino. Hay varios sistemas de determinación del riesgo que incluyen a los insectos y también existen diversos organismos de coordinación internacional que ya tienen experiencia en sentar pautas sobre los riesgos en la materia. Todos los interlocutores del sector se beneficiarían de una visión global e integrada del transporte de insectos, que remita a diferentes tipos de riesgo y categorías de magnitud, sin necesidad de buscar un sistema único que exija consenso universal. Las propuestas para gestionar la incertidumbre y la falta de información en el caso de envíos infrecuentes o de pequeñas dimensiones, por ejemplo, no deben interferir en el transporte de grandes cantidades de insectos vivos, que ya está sirviendo a objetivos estratégicos en varios sectores.


Assuntos
Pesquisa Biomédica , Drosophila melanogaster , Animais , Comércio , Insetos
4.
J Gerontol Nurs ; 48(9): 47-51, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36007211

RESUMO

The objectives of the current process improvement project were to improve access to health care and enhance care for older adults living in rural areas and to decrease morbidity and mortality. This project implemented an evidence-based screening tool, the Rapid Geriatric Assessment (RGA), as a routine screening in a patient-centered medical home for older adults in rural areas. Z-testing was used to measure the change, defined as scoring positive for at least one of four geriatric syndromes, as a result of using the RGA tool. Approximately one third had at least one such change following implementation of the RGA. In addition to the change in geriatric conditions, a significant change (48%) was noted in the number of patients who implemented an advance directive. We recommend the RGA be integrated in routine screening as it can help providers establish a targeted treatment plan for older adults who may be at increased risk for burden of disease. [Journal of Gerontological Nursing, 48(9), 47-51.].


Assuntos
Avaliação Geriátrica , Enfermagem Geriátrica , Idoso , Atenção à Saúde , Humanos , Síndrome
5.
Phys Rev Lett ; 127(22): 222501, 2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34889627

RESUMO

Mass and angle distributions for the ^{52}Cr+^{198}Pt and ^{54}Cr+^{196}Pt reactions (both forming ^{250}No) were measured and subtracted, giving new information on fast quasifission mass evolution, and the first direct determination of the dependence of sticking times on angular momentum. TDHF calculations showed good agreement with average experimental values, but experimental mass distributions unexpectedly extended to symmetric splits while the peak yield remained close to the initial masses. This implies a strong role of fluctuations in mass division early in the collision, giving insights into the transition from fast energy dissipative deep-inelastic collisions to quasifission.

6.
Phys Rev Lett ; 124(21): 212503, 2020 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-32530691

RESUMO

The heaviest bound isotope of boron ^{19}B has been investigated using exclusive measurements of its Coulomb dissociation, into ^{17}B and two neutrons, in collisions with Pb at 220 MeV/nucleon. Enhanced electric dipole (E1) strength is observed just above the two-neutron decay threshold with an integrated E1 strength of B(E1)=1.64±0.06(stat)±0.12(sys) e^{2} fm^{2} for relative energies below 6 MeV. This feature, known as a soft E1 excitation, provides the first firm evidence that ^{19}B has a prominent two-neutron halo. Three-body calculations that reproduce the energy spectrum indicate that the valence neutrons have a significant s-wave configuration and exhibit a dineutronlike correlation.

7.
Phys Rev Lett ; 122(10): 102501, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30932665

RESUMO

Above-barrier complete fusion involving nuclides with low binding energy is typically suppressed by 30%. The mechanism that causes this suppression, and produces the associated incomplete fusion products, is controversial. We have developed a new experimental approach to investigate the mechanisms that produce incomplete fusion products, combining singles and coincidence measurements of light fragments and heavy residues in ^{7}Li+^{209}Bi reactions. For polonium isotopes, the dominant incomplete fusion product, only a small fraction can be explained by projectile breakup followed by capture: the dominant mechanism is triton cluster transfer. Suppression of complete fusion is therefore primarily a consequence of clustering in weakly bound nuclei rather than their breakup prior to reaching the fusion barrier. This implies that suppression of complete fusion will occur in reactions of nuclides where strong clustering is present.

8.
Phys Rev Lett ; 122(23): 232503, 2019 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-31298876

RESUMO

Superheavy elements are formed in fusion reactions which are hindered by fast nonequilibrium processes. To quantify these, mass-angle distributions and cross sections have been measured, at beam energies from below-barrier to 25% above, for the reactions of ^{48}Ca, ^{50}Ti, and ^{54}Cr with ^{208}Pb. Moving from ^{48}Ca to ^{54}Cr leads to a drastic fall in the symmetric fission yield, which is reflected in the measured mass-angle distribution by the presence of competing fast nonequilibrium deep inelastic and quasifission processes. These are responsible for reduction of the compound nucleus formation probablity P_{CN} (as measured by the symmetric-peaked fission cross section), by a factor of 2.5 for ^{50}Ti and 15 for ^{54}Cr in comparison to ^{48}Ca. The energy dependence of P_{CN} indicates that cold fusion reactions (involving ^{208}Pb) are not driven by a diffusion process.

9.
Rev Sci Tech ; 38(1): 173-184, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31564732

RESUMO

Antimicrobial drugs are a precious resource, responsible for saving millions of lives since their discovery. Unfortunately, some antimicrobials are rapidly losing their effectiveness due to the development and spread of antimicrobial resistance (AMR), a multi-faceted and complex problem affecting humans, animals, plants and the environment. While AMR is a global problem, in this paper, the authors briefly highlight some ongoing efforts in the United States of America aimed at integrating a One Health approach into policies and programmes that address this important health threat.


Les antibiotiques sont des ressources de grande valeur qui ont sauvé des millions de vies depuis leur découverte. Malheureusement, certains agents antimicrobiens perdent rapidement leur efficacité en raison de l'apparition et propagation des résistances à ces agents, phénomène complexe et multidimensionnel qui affecte l'homme, les animaux, les plantes et l'environnement. La résistance aux agents antimicrobiens est un problème mondial ; dans cet article, les auteurs décrivent certaines initiatives actuellement mises en oeuvre aux États-Unis d'Amérique pour intégrer l'approche Une seule santé dans les politiques et les programmes conçus pour lutter contre cette menace sanitaire majeure.


Los fármacos antimicrobianos son un recurso valiosísimo, cuyo uso ha salvado millones de vidas desde que fueron descubiertos. Lamentablemente, algunos de ellos están perdiendo rápidamente eficacia debido a la aparición y propagación de resistencias, lo que plantea un problema tan complejo como poliédrico, que afecta a personas, animales, plantas y ecosistemas. Aunque la dimensión del problema es planetaria, los autores destacan aquí brevemente algunas de las iniciativas en curso en los Estados Unidos de América que tienen por objetivo integrar los planteamientos de Una sola salud en el conjunto de políticas y programas desde los cuales se aborda esta importante amenaza sanitaria.


Assuntos
Farmacorresistência Bacteriana , Política de Saúde , Saúde Única , Animais , Anti-Infecciosos , Política de Saúde/tendências , Humanos , Estados Unidos
10.
Phys Rev Lett ; 120(2): 022501, 2018 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-29376683

RESUMO

Energy dissipative processes play a key role in how quantum many-body systems dynamically evolve toward equilibrium. In closed quantum systems, such processes are attributed to the transfer of energy from collective motion to single-particle degrees of freedom; however, the quantum many-body dynamics of this evolutionary process is poorly understood. To explore energy dissipative phenomena and equilibration dynamics in one such system, an experimental investigation of deep-inelastic and fusion-fission outcomes in the ^{58}Ni+^{60}Ni reaction has been carried out. Experimental outcomes have been compared to theoretical predictions using time dependent Hartree-Fock and time dependent random phase approximation approaches, which, respectively, incorporate one-body energy dissipation and fluctuations. Excellent quantitative agreement has been found between experiment and calculations, indicating that microscopic models incorporating one-body dissipation and fluctuations provide a potential tool for exploring dissipation in low-energy heavy ion collisions.

11.
Nature ; 481(7380): 167-9, 2012 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-22237108

RESUMO

Most known extrasolar planets (exoplanets) have been discovered using the radial velocity or transit methods. Both are biased towards planets that are relatively close to their parent stars, and studies find that around 17-30% (refs 4, 5) of solar-like stars host a planet. Gravitational microlensing, on the other hand, probes planets that are further away from their stars. Recently, a population of planets that are unbound or very far from their stars was discovered by microlensing. These planets are at least as numerous as the stars in the Milky Way. Here we report a statistical analysis of microlensing data (gathered in 2002-07) that reveals the fraction of bound planets 0.5-10 AU (Sun-Earth distance) from their stars. We find that 17(+6)(-9)% of stars host Jupiter-mass planets (0.3-10 M(J), where M(J) = 318 M(⊕) and M(⊕) is Earth's mass). Cool Neptunes (10-30 M(⊕)) and super-Earths (5-10 M(⊕)) are even more common: their respective abundances per star are 52(+22)(-29)% and 62(+35)(-37)%. We conclude that stars are orbited by planets as a rule, rather than the exception.

12.
J Environ Qual ; 47(5): 1275-1283, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30272780

RESUMO

Heavy manure-derived contamination of soils can make animal congregating areas nonpoint sources for environmental pollution. In situ soil stabilization is a cost-effective management strategy with a focus on lowering contaminant availability and limiting release to the environment. Soil stabilizing amendments can help mitigate the negative environmental impacts of contaminated soils. In this 2-yr study, we examined the effects of adding no amendment (control) or treating with alum [Al (SO)⋅18HO] or biochar as soil amendments on Mehlich-3 extractable soil P, Cu, and Zn contents, antimicrobial monensin concentrations, total bacteria (16S ribosomal RNA [rRNA] gene), antibiotic resistance genes (1 and B), and Class 1 integrons (1) in an abandoned beef backgrounding setting. The alum reduced soil P (1374 to 1060 mg kg), Cu (7.7 to 3.2 mg kg), and Zn (52.4 to 19.6 mg kg) contents. Both alum and biochar reduced monesin concentrations (1.8 to 0.7 and 2.1 to 1.1 ng g, respectively). All the treatments harbored consistent 16 rRNA concentrations (10 copies g) throughout. The B gene concentration (10 copies g) was lower than either the 1 or the 1 genes (10 copies g), regardless of treatments. However, concentrations of all genes in the soils of animal congregation areas were higher than those in background soils with the least animal impact. In contrast with the effect on other contaminants, the effect of soil amendments on bacteria with antibiotic resistance genes was not biologically significant. Future research should be directed toward evaluating effective alternative methods to mitigate these bacterial populations.


Assuntos
Recuperação e Remediação Ambiental/métodos , Carne Vermelha , Poluentes do Solo/análise , Compostos de Alúmen/química , Carvão Vegetal/química , Poluentes do Solo/química
13.
Phys Rev Lett ; 119(22): 222502, 2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-29286775

RESUMO

The atomic numbers and the masses of fragments formed in quasifission reactions are simultaneously measured at scission in ^{48}Ti+^{238}U reactions at a laboratory energy of 286 MeV. The atomic numbers are determined from measured characteristic fluorescence x rays, whereas the masses are obtained from the emission angles and times of flight of the two emerging fragments. For the first time, thanks to this full identification of the quasifission fragments on a broad angular range, the important role of the proton shell closure at Z=82 is evidenced by the associated maximum production yield, a maximum predicted by time-dependent Hartree-Fock calculations. This new experimental approach gives now access to precise studies of the time dependence of the N/Z (neutron over proton ratios of the fragments) evolution in quasifission reactions.

14.
J Dairy Sci ; 98(3): 1851-5, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25529418

RESUMO

Recently, a circadian rhythm of milk and milk component synthesis has been characterized that is partially dependent on the timing of feed intake. Our objective was to determine if inhibition of milk fat synthesis during diet-induced milk fat depression occurred to a higher degree during certain phases of the day. A retrospective analysis was conducted on 2 experiments that induced milk fat depression while milking cows 3 times per day at equal intervals. The response at each milking was analyzed using mixed model ANOVA with repeated measures. In experiment 1, nine multiparous Holstein cows were arranged in a 3×3 Latin square design, and treatments were control, 3-d intravenous infusion of 10 g/d of trans-10,cis-12 conjugated linoleic acid (CLA), and a low-forage and high-fat diet for 10 d. In experiment 2, ten multiparous ruminally cannulated cows were arranged in a replicated design and milk samples were collected during a control period or after 5 d of abomasal infusion of 10 g/d of CLA. The daily pattern of milk fat concentration and yield did not differ between treatments in either experiment. In experiment 1, an effect was found of treatment and milking time on milk fat concentration and yield. Similarly, in experiment 2, main effects were found of treatment and milking time on milk fat concentration and an effect of treatment, but no effect of milking time on milk fat yield. Milk fat percent was increased from 3.41 to 4.06% and 3.25 to 3.48% from the morning to the afternoon milking in experiments 1 and 2, respectively. Additionally, milk fatty acid profile, including trans intermediates, was changed over the day in experiment 1, but the magnitude of the changes were small and the pattern did not differ among treatments. A daily rhythm of milk fat concentration and yield was observed in cows milked 3 times a day, but milk fat depression decreases milk fat yield equally over the day.


Assuntos
Bovinos/fisiologia , Ritmo Circadiano , Dieta/veterinária , Gorduras/análise , Ácidos Linoleicos Conjugados/administração & dosagem , Leite/química , Animais , Dieta Hiperlipídica , Gorduras Insaturadas na Dieta/administração & dosagem , Fibras na Dieta/administração & dosagem , Ácidos Graxos/análise , Feminino , Lactação , Lipídeos/biossíntese , Estudos Retrospectivos
15.
J Environ Qual ; 44(6): 1892-902, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26641341

RESUMO

Contaminants associated with manure in animal production sites are of significant concern. Unless properly managed, manure-derived soil nutrients in livestock production sites can deteriorate soil and water quality. This 3-yr study evaluated a soil nutrient management strategy with four sequentially imposed management practices: 12-mo backgrounding (BG), manure removal from the feeder area (FD), 12-mo destocking (DS), and 12-mo grass hay harvesting (H) in a small backgrounding feedlot. Resulting soil nutrient levels, total (), and N cycling bacterial ( and ) populations after each management practice in feedlot feeder and grazing (GR) areas and in crop grown at the control location (CT) were measured. Irrespective of management practice, FD contained greater soil nutrient concentrations than the GR and CT. Regardless of management practice, total bacteria cells (1.4 × 10 cells g soil) and nitrate reducers (5.2 × 10 cells g soil) were an order of magnitude higher in the FD than in the GR and CT, whereas nitrifying bacteria concentrations (1.4 × 10 cells g soil) were higher in the GR. Manure removal from the feeder area reduced M3-P (39%), total C (21%), total N (23%), NH-N (47%), and NO-N (93%) levels established in the FD during BG. Destocking lowered total C and N (45%) in the FD and NH-N (47%), NO-N (76%), and Zn (16%) in the GR. Hay harvesting reduced all soil nutrients in the FD and GR marginally. The management strategy has potential to lower soil nutrient concentrations, control soil nutrient buildup, and limit nutrient spread within the feedlot.

16.
Cell Microbiol ; 15(12): 2080-92, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23870035

RESUMO

Helicobacter pylori establishes a chronic lifelong infection in the human gastric mucosa, which may lead to peptic ulcer disease or gastric adenocarcinoma. The human beta-defensins (hßDs) are antimicrobial peptides, hßD1 being constitutively expressed in the human stomach. We hypothesized that H. pylori may persist, in part, by downregulating gastric hßD1 expression. We measured hßD1 and hßD2 expression in vivo in relation to the presence, density and severity of H. pylori infection, investigated differential effects of H. pylori virulence factors, and studied underlying signalling mechanisms in vitro. Significantly lower hßD1 and higher hßD2 mRNA and protein concentrations were present in gastric biopsies from infected patients. Those patients with higher-level bacterial colonization and inflammation had significantly lower hßD1 expression, but there were no differences in hßD2. H. pylori infection of human gastric epithelial cell lines also downregulated hßD1. Using wild-type strains and isogenic mutants, we showed that a functional cag pathogenicity island-encoded type IV secretion system induced this downregulation. Treatment with chemical inhibitors or siRNA revealed that H. pylori usurped NF-κB signalling to modulate hßD1 expression. These data indicate that H. pylori downregulates hßD1 expression via NF-κB signalling, and suggest that this may promote bacterial survival and persistence in the gastric niche.


Assuntos
Infecções por Helicobacter/imunologia , Helicobacter pylori/metabolismo , Evasão da Resposta Imune/imunologia , beta-Defensinas/biossíntese , Sistemas de Secreção Bacterianos , Linhagem Celular , Regulação para Baixo , Mucosa Gástrica/imunologia , Mucosa Gástrica/metabolismo , Mucosa Gástrica/microbiologia , Infecções por Helicobacter/metabolismo , Infecções por Helicobacter/microbiologia , Helicobacter pylori/imunologia , Helicobacter pylori/patogenicidade , Humanos , Proteína Quinase 1 Ativada por Mitógeno/genética , Subunidade p50 de NF-kappa B/genética , Interferência de RNA , RNA Mensageiro/biossíntese , RNA Interferente Pequeno , Transdução de Sinais , Estômago/imunologia , Estômago/microbiologia , Fator de Transcrição RelA/genética , beta-Defensinas/genética
17.
Appl Opt ; 53(18): 3993-4001, 2014 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-24979432

RESUMO

An optical fiber sensor based on long-period gratings (LPG) for selective measurements of flap- and edge-wise bending of a wind turbine blade is presented. Two consecutive LPGs separated by 40 mm interfere to improve resolution and reduce noise in a D-shaped fiber. The mode profile of the device was characterized experimentally to provide a model describing the mode couplings. The sensor was tested on a wind turbine blade.

18.
J Environ Qual ; 43(5): 1546-58, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25603240

RESUMO

Poultry litter (PL) is a by-product of broiler production. Most PL is land applied. Land-applied PL is a valuable nutrient source for crop production but can also be a route of environmental contamination with manure-borne bacteria. The objective of this study was to characterize the fate of pathogens, fecal indicator bacteria (FIB), and bacteria containing antibiotic resistance genes (ARGs) after application of PL to soils under conventional till or no-till management. This 2-yr study was conducted in accordance with normal agricultural practices, and microbial populations were quantified using a combination of culture and quantitative, real-time polymerase chain reaction analysis. Initial concentrations of in PL were 5.4 ± 3.2 × 10 cells g PL; sp. was not detected in the PL but was enriched periodically from PL-amended soils. was detected in PL (1.5 ± 1.3 × 10 culturable or 1.5 ± 0.3 × 10 genes g) but was rarely detected in field soils, whereas enterococci (1.5 ± 0.5 × 10 cells g PL) were detected throughout the study. These results suggest that enterococci may be better FIB for field-applied PL. Concentrations of ARGs for sulfonamide, streptomycin, and tetracycline resistance increased up to 3.0 orders of magnitude after PL application and remained above background for up to 148 d. These data provide new knowledge about important microbial FIB, pathogens, and ARGs associated with PL application under realistic field-based conditions.

19.
Conserv Physiol ; 12(1): coae034, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38827188

RESUMO

Estimating the survival probability of animals released from fisheries can improve the overall understanding of animal biology with implications for fisheries management, conservation and animal welfare. Vitality indicators are simple visual measures of animal condition that change in response to stressors (like fisheries capture) and can be assessed to predict post-release survival. These indicators typically include immediate reflex responses which are typically combined into a score. Vitality indicators are straight-forward and non-invasive metrics that allow users to quantify how close (or far) an animal is from a normal, 'healthy' or baseline state, which in turn can be correlated with outcomes such as survival probability, given appropriate calibration. The literature on using vitality indicators to predict post-release survival of animals has grown rapidly over the past decade. We identified 136 papers that used vitality indicators in a fisheries context. These studies were primarily focused on marine and freshwater fishes, with a few examples using herptiles and crustaceans. The types of vitality indicators are diverse and sometimes taxa-specific (e.g. pinching leg of turtles, spraying water at nictitating membrane of sharks) with the most commonly used indicators being those that assess escape response or righting response given the vulnerability of animals when those reflexes are impaired. By presenting Pacific salmon fisheries as a case study, we propose a framework for using vitality indicators to predict survival across taxa and fisheries.

20.
J Appl Microbiol ; 115(2): 334-45, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23647636

RESUMO

AIMS: To evaluate the persistence of Mycobacterium avium subsp paratuberculosis (Myco. paratuberculosis), Salmonella enterica serotype Typhimurium (Salm.Typhimurium) and a commensal Escherichia coli (E. coli) isolate under the low pH and high organic acid (OA) conditions of ensiling of forages. METHODS AND RESULTS: Decay rates and the time required to obtain a 90% reduction in cell concentration were calculated following (i) exposure to buffered OA (pH 4.0, 5.0, 6.0 or 7.0) (ii) exposure to silage exudates and (iii) survival through ensiling of forage materials. Salm. Typhimurium had higher decay rates in silage exudates (-0.5601 day(-1) ) than did E. coli (-0.1265 day(-1) ), but both exhibited lower decay rates in silage than in OA or silage exudates. Myco. paratuberculosis showed no decrease in silage and decay rates in silage exudates were significantly lower (2-12 times) than for the other two organisms. CONCLUSIONS: Escherichia coli, Salm. Typhimurium and Myco. paratuberculosis exhibit marked differences in response to acidity. All three organisms show acid resistance, but Myco. paratuberculosis in particular, if present in manure and applied to forage grasses, may survive the low pH and high OA of the ensilaging process; silage may therefore be a potential route of infection if ingested by a susceptible animal. SIGNIFICANCE AND IMPACT OF STUDY: This information contributes to the understanding of potential risks associated with silage preservation and contamination of livestock feed with manure-borne pathogens.


Assuntos
Escherichia coli/crescimento & desenvolvimento , Mycobacterium avium subsp. paratuberculosis/crescimento & desenvolvimento , Salmonella typhimurium/crescimento & desenvolvimento , Silagem/microbiologia , Animais , Ácido Cítrico , Escherichia coli/isolamento & purificação , Concentração de Íons de Hidrogênio , Esterco/microbiologia , Viabilidade Microbiana , Mycobacterium avium subsp. paratuberculosis/isolamento & purificação , Salmonella typhimurium/isolamento & purificação
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