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1.
J Prev Alzheimers Dis ; 11(4): 889-894, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39044498

RESUMEN

BACKGROUND: The Anti-Amyloid Treatment in Asymptomatic Alzheimer's Disease (A4) and Longitudinal Evaluation of Amyloid Risk and Neurodegeneration (LEARN) studies were conducted between 2014 and 2023, with enrollment completed in 2017 and final study results reported in 2023. The study screening process involved the collection of initial clinical, cognitive, neuroimaging, and genetic measures to determine eligibility. Once randomized, enrolled participants were assessed every four weeks over a 4.5-year follow-up period during which longitudinal clinical, cognitive, and neuroimaging measures were collected. A large number of longitudinal fluid biospecimens were also collected and banked. Consistent with the NIH data sharing policy and the principles of Open Science, the A4/LEARN investigators aimed to share data as broadly and early as possible while still protecting participant privacy and confidentiality and the scientific integrity of the studies. OBJECTIVES: We describe the approach, methods, and platforms used to share the A4 and LEARN pre-randomization study data for secondary research use. Preliminary results measuring the impact of these efforts are also summarized. We conclude with a discussion of lessons learned and next steps. DESIGN: The materials shared included de-identified quantitative and image data, analysis software, instruments, and documentation. SETTING: The A4 and LEARN Studies were conducted at 67 clinical trial sites in the United States, Canada, Japan, and Australia. PARTICIPANTS: The A4 study screened (n=6763), enrolled, and randomized (n=1169) participants between the ages of 65 and 85 with a blinded follow-up period of 240 weeks followed by an open-label period of variable length. The LEARN study screened and enrolled individuals (n=538) who were ineligible for the A4 study based on nonelevated measures of amyloid accumulation using positron emission tomography imaging (amyloid PET). MEASUREMENTS: We provide descriptive measures of the data shared and summarize the frequency, characteristics, and status of all data access requests submitted to date. We evaluate the scientific impact of the data-sharing effort by conducting a literature search to identify related publications. RESULTS: The A4 and LEARN pre-randomization study data were released in December 2018. As of May 8, 2024, 1506 requests have been submitted by investigators and citizen scientists from more than 50 countries. We identified 49 peer-reviewed publications that acknowledge the A4/LEARN study. CONCLUSIONS: Our initial results provide evidence supporting the feasibility and scientific utility of broad and timely sharing of Alzheimer's disease trial data.


Asunto(s)
Enfermedad de Alzheimer , Difusión de la Información , Humanos , Estudios Longitudinales , Anciano , Neuroimagen , Masculino , Femenino , Ensayos Clínicos Controlados Aleatorios como Asunto , Anticuerpos Monoclonales Humanizados
2.
J Food Sci ; 89(2): 1225-1242, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38204401

RESUMEN

This study used data from consumer testing, descriptive analysis (DA), and preference mapping to determine the sensory characteristics of pear cultivars from two harvest seasons in the Pacific Northwest (PNW). A trained sensory panel (n = 10) used generic DA to evaluate multiple sensory modalities of 22 pear cultivars. Six pears from summer and six from winter season were evaluated by consumers (n = 219) to assess their liking of different attributes. Results of the DA showed the trained panel significantly discriminated the summer and winter pears on most of the sensory modalities. To identify the attributes driving consumer acceptability, external preference mapping was applied. Attributes such as pear aroma, pear flavor, sweet, sour, and juicy were the most contributory attributes to the liking of the summer pears. Conversely, fermented aroma, stemmy-woody aroma, fermented flavor, stemmy-woody flavor, and grainy-gritty attributes were associated with a reduction in consumer liking. Summer cultivars, "Bartlett," coded pear 573, and "Seckel" had the broadest preference, satisfying 60% to 80% of the consumers. Seventy-five percent of the consumers identified winter cultivars "Comice" and "Paragon" as the most appealing. Overall, cluster analysis showed that different pears appeal to different types of consumers; however, summer cultivars like "Bartlett" and "Seckel" and winter cultivars like "Comice" and "Paragon" would appeal to the greatest number of consumers in the PNW market. PRACTICAL APPLICATION: Sensory attributes like pear flavor, sweet, and juicy, were important drivers of liking for pear consumers in the Pacific Northwest. These results should prove useful to pear growers and marketers to increase pear consumption in the United States.


Asunto(s)
Benzopiranos , Pyrus , Cloruro de Tolonio , Estados Unidos , Preferencias Alimentarias , Comportamiento del Consumidor , Gusto , Noroeste de Estados Unidos , Frutas
3.
PLoS One ; 17(12): e0270792, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36512609

RESUMEN

This study estimates consumers' willingness to pay for specific product (quality) and process (agronomic) attributes of table grapes, including taste, texture, external appearance, and the expected number of chemical applications, and for the breeding technology used to develop the plant. Considering varietal traits, on average our survey respondents were willing to pay the highest price premiums for specific offers of improvements in table grape taste and texture, followed by external appearance and expected number of chemical applications. Considering breeding methods, on average our respondents were willing to pay a small premium for table grapes developed using conventional breeding rather than gene editing (e.g., CRISPR). Results from a latent class model identify four different groups of consumers with distinct preferences for grape quality attributes and breeding technologies. The group of consumers most likely to reject gene editing considers both genetic engineering and gene editing to be breeding technologies that produce foods that are morally unacceptable and not safe to eat.


Asunto(s)
Comportamiento del Consumidor , Vitis , Gusto , Vitis/genética , Edición Génica , Fitomejoramiento
4.
Sci Rep ; 12(1): 17831, 2022 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-36284121

RESUMEN

The magnonic band structure of two-dimensional chiral magnonic crystals is theoretically investigated. The proposed metamaterial involves a three-dimensional architecture, where a thin ferromagnetic layer is in contact with a two-dimensional periodic array of heavy-metal square islands. When these two materials are in contact, an anti-symmetric exchange coupling known as the Dzyaloshinskii-Moriya interaction (DMI) arises, which generates nonreciprocal spin waves and chiral magnetic order. The Landau-Lifshitz equation and the plane-wave method are employed to study the dynamic magnetic behavior. A systematic variation of geometric parameters, the DMI constant, and the filling fraction allows the examination of spin-wave propagation features, such as the spatial profiles of the dynamic magnetization, the isofrequency contours, and group velocities. In this study, it is found that omnidirectional flat magnonic bands are induced by a sufficiently strong Dzyaloshinskii-Moriya interaction underneath the heavy-metal islands, where the spin excitations are active. The theoretical results were substantiated by micromagnetic simulations. These findings are relevant for envisioning applications associated with spin-wave-based logic devices, where the nonreciprocity and channeling of the spin waves are of fundamental and practical scientific interest.

5.
Poult Sci ; 101(11): 102138, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36126448

RESUMEN

Newcastle disease (ND) is a highly contagious viral disease that constantly threatens poultry production. The velogenic (highly virulent) form of ND inflicts the most damage and can lead to 100% mortality in unvaccinated village chicken flocks. This study sought to characterize responses of local chickens in Ghana after challenging them with lentogenic and velogenic Newcastle disease virus (NDV) strains. At 4 wk of age, chicks were challenged with lentogenic NDV. Traits measured were pre- and post-lentogenic infection growth rates (GR), viral load at 2 and 6 d post-lentogenic infection (DPI), viral clearance rate and antibody levels at 10 DPI. Subsequently, the chickens were naturally exposed to velogenic NDV (vNDV) after anti-NDV antibody titers had waned to levels ≤1:1,700. Body weights and blood samples were again collected for analysis. Finally, chickens were euthanized and lesion scores (LS) across tissues were recorded. Post-velogenic exposure GR; antibody levels at 21 and 34 days post-velogenic exposure (DPE); LS for trachea, proventriculus, intestines, and cecal tonsils; and average LS across tissues were measured. Variance components and heritabilities were estimated for all traits using univariate animal models. Mean pre- and post-lentogenic NDV infection GRs were 6.26 g/day and 7.93 g/day, respectively, but mean post-velogenic NDV exposure GR was -1.96 g/day. Mean lesion scores ranged from 0.52 (trachea) to 1.33 (intestine), with males having significantly higher (P < 0.05) lesion scores compared to females. Heritability estimates for the lentogenic NDV trial traits ranged from moderate (0.23) to high (0.55) whereas those for the vNDV natural exposure trial were very low (≤ 0.08). Therefore, in contrast to the vNDV exposure trial, differences in the traits measured in the lentogenic challenge were more affected by genetics and thus selection for these traits may be more feasible compared to those following vNDV exposure. Our results can form the basis for identifying local chickens with improved resilience in the face of NDV infection for selective breeding to improve productivity.


Asunto(s)
Enfermedad de Newcastle , Enfermedades de las Aves de Corral , Femenino , Animales , Virus de la Enfermedad de Newcastle , Pollos , Ghana/epidemiología , Enfermedades de las Aves de Corral/prevención & control , Enfermedad de Newcastle/prevención & control
6.
Lett Appl Microbiol ; 75(3): 680-688, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35687297

RESUMEN

Pseudomonas aeruginosa is one of the most worrisome infectious bacteria due to its intrinsic and acquired resistance against several antibiotics and the recalcitrance of its infections; hence, the development of novel antimicrobials effective against multidrug-resistant P. aeruginosa is mandatory. In this work, silver nanoparticles obtained by green synthesis using a leaf extract and fungi were tested against a battery of clinical strains from cystic fibrosis, pneumonia and burnt patients, some of them with multidrug resistance. Both nanoparticles showed a potent antibacterial effect, causing severe damage to the cell wall, membrane and DNA, and inducing the production of reactive oxygen species. Moreover, the nanoparticles derived from fungi showed synergistic antibacterial effects with the antibiotics meropenem and levofloxacin for some clinical strains and both kinds of nanoparticles were nontoxic for larvae of the moth Galleria mellonella, encouraging further research for their implementation in the treatment of P. aeruginosa infections.


Asunto(s)
Nanopartículas del Metal , Infecciones por Pseudomonas , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Farmacorresistencia Bacteriana Múltiple , Humanos , Levofloxacino/farmacología , Levofloxacino/uso terapéutico , Meropenem/farmacología , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/farmacología , Infecciones por Pseudomonas/tratamiento farmacológico , Infecciones por Pseudomonas/microbiología , Pseudomonas aeruginosa , Especies Reactivas de Oxígeno , Plata/farmacología
7.
Avian Dis ; 65(3): 373-380, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34427410

RESUMEN

Infectious bronchitis virus (IBV) is a gammacoronavirus that primarily induces an upper respiratory disease in chickens, also affecting the urogenital tract and occasionally leading to a condition called false layer syndrome (FLS), where sexually mature hens ovulate normally but are unable to lay eggs. Here, we describe an outbreak of FLS in Arizona from which an IBV variant that is nearly 90% homologous to DMV/1639 using the Spike subunit 1 gene, named AZ/FLS/17, was isolated and used in challenge experiments. Three-day-old specific-pathogen-free chicks were challenged with AZ/FLS/17 or M41 in high and low doses, and the disease outcomes were compared. Overall, no differences in microscopic lesions or viral loads in the reproductive tract were detected between AZ/FLS/17- and M41-infected birds. To minimize the losses linked to FLS in the problematic flocks, an updated live-attenuated IBV vaccine protocol including the use of the Ma5 strain at the hatchery was implemented, resulting in a drastic reduction of false layers in the subsequent flocks. To monitor the circulation of wild-type and vaccine strains in this population, a molecular surveillance study was performed. Samples were collected at 1, 7, 14, and 21 days of age, and from laying hens at 30 and 36 wk. In older birds, the IBV strains detected were more diverse than at 1 and 7 days of age. Nevertheless, live vaccine combinations are still widely used to decrease the losses caused by FLS in commercial egg laying flocks worldwide.


Caracterización de un virus de la bronquitis infecciosa aislado de aves de postura comerciales que padecían el síndrome de la falsa ponedora. El virus de la bronquitis infecciosa (IBV) es un gammacoronavirus que induce principalmente una enfermedad de las vías respiratorias superiores en los pollos, que también afecta el tracto urogenital y ocasionalmente conduce a una condición llamada síndrome de la falsa ponedora (FLS), donde las gallinas sexualmente maduras ovulan normalmente pero no pueden producir huevos. En este estudio se describe un brote del síndrome de la falsa ponedora en Arizona a partir del cual se aisló una variante del virus de bronquitis que es casi 90% similar a la variante DMV/1639 usando el gene S1, la cual se denominó AZ/FLS/17, y se usó en experimentos de desafío. Pollos de tres días de edad libres de patógenos específicos (SPF) fueron desafiados con el virus AZ/FLS/17 o con el virus M41 en dosis altas y bajas, y se compararon los resultados de la enfermedad. En general, no se detectaron diferencias en las lesiones microscópicas o en las cargas virales en el tracto reproductivo entre las aves infectadas con el virus AZ/FLS/17 y el virus M41. Para minimizar las pérdidas relacionadas con el síndrome de la falsa ponedora en las parvadas problemáticas, se implementó un protocolo actualizado con vacuna viva atenuada contra la bronquitis infecciosa que incluía el uso de la cepa Ma5 en la incubadora, lo que resultó en una reducción drástica de las gallinas falsas ponedoras en las parvadas subsecuentes. Para monitorear la circulación de cepas de tipo silvestre y vacunales en esta población, se realizó un estudio de vigilancia molecular. Se recolectaron muestras a los 1, 7, 14 y 21 días de edad y de gallinas de postura a las 30 y 36 semanas. En aves mayores, las cepas del virus de bronquitis detectadas fueron más diversas que a los días 1 y 7 de edad. Sin embargo, las combinaciones de vacunas vivas todavía se utilizan ampliamente para disminuir las pérdidas causadas por el síndrome de la falsa ponedora en las parvadas de postura de huevo comercial en todo el mundo.


Asunto(s)
Infecciones por Coronavirus , Virus de la Bronquitis Infecciosa , Enfermedades de las Aves de Corral , Vacunas Virales , Animales , Pollos , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/veterinaria , Femenino , Virus de la Bronquitis Infecciosa/genética , Organismos Libres de Patógenos Específicos
8.
Foods ; 10(7)2021 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-34359493

RESUMEN

A home-use test (HUT) is one method that provides a measure of ecological validity as the product is consumed in home under common daily use circumstances. One product that benefits from being evaluated in-home are ready-to-eat (RTE) meals. This study determined consumer acceptance of microwave-thermally-pasteurized jambalaya, a multi-meat and vegetable dish from American Cajun cuisine, and a control (cooked frozen jambalaya) through an on-line home-use test (HUT) over a 12-week storage period. Paralleling the HUT, an online auction determined consumers' willingness to pay. The study also explored how the social environment may impact the liking of the meals when a partner of the participants joined the sensory evaluation of the meals. Consumers (n = 50) evaluated microwave-processed jambalaya stored at 2 °C and a control (cooked frozen jambalaya stored at -31 °C) after 2, 8 and 12 weeks of storage. Consumer liking of different sensory attributes was measured. Participants could choose to share the meals with a partner as a way to enhance ecological validity. The responses from 21 partners to the sensory-related questions were collected. After the sensory evaluation, the participants bid on the meal they had just sampled. Results showed that processing method (microwave vs. control) did not significantly influence the measured sensory attributes. Only flavor liking decreased over storage time (p < 0.05). The inclusion of partners significantly increased (p = 0.04) the liking of the appearance of the meals. The mean values of the bids for the meals ranged from $3.33-3.74, matching prices of commercially available jambalaya meals. This study found suggests that the shelf- life of microwave-processed meals could be extended up to 12 weeks without changing its overall liking. The study also shows the importance of exploring HUT methodology for the evaluation of consumers' acceptance of microwave-processed jambalaya and how including a partner could contribute to enhance ecological validity.

9.
J Food Sci ; 86(8): 3658-3671, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34255388

RESUMEN

In this study, we estimate consumers' willingness to pay (WTP) for ready meals preserved using microwave assisted pasteurization systems (MAPS)-a novel pasteurization technology, compared to frozen, ready meals. We conducted a laboratory multi-round experimental auction for two samples of ready meal jambalaya in which appearance and sensory evaluation along with extrinsic information was sequentially disclosed to panelists. Our results suggest that when participants tasted the meals and formed an opinion from the meal itself, the liking of appearance and sensory attributes were the most impactful factors for participants' WTP regardless of other available extrinsic (name of the preservation technology and environmental impacts of each technology) attributes. The words "microwave" and "pasteurization" did not negatively impact the WTP. The order in which intrinsic and extrinsic attributes were evaluated and presented did not impact absolute WTP values, but the order did impact the weight of each attribute type on the WTP. PRACTICAL APPLICATION: The sensory perceptions had a larger effect than the name of the preservation technology and environmental impacts on the willingness to pay (WTP) for ready meals. The order of presented information to panelists did not impact absolute values of WTP. The words "microwave" and "pasteurization" did not have a negative effect on WTP.


Asunto(s)
Comportamiento del Consumidor , Gusto , Humanos , Microondas , Pasteurización
10.
J Phys Condens Matter ; 33(41)2021 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-33662946

RESUMEN

Magnonics is a budding research field in nanomagnetism and nanoscience that addresses the use of spin waves (magnons) to transmit, store, and process information. The rapid advancements of this field during last one decade in terms of upsurge in research papers, review articles, citations, proposals of devices as well as introduction of new sub-topics prompted us to present the first roadmap on magnonics. This is a collection of 22 sections written by leading experts in this field who review and discuss the current status besides presenting their vision of future perspectives. Today, the principal challenges in applied magnonics are the excitation of sub-100 nm wavelength magnons, their manipulation on the nanoscale and the creation of sub-micrometre devices using low-Gilbert damping magnetic materials and its interconnections to standard electronics. To this end, magnonics offers lower energy consumption, easier integrability and compatibility with CMOS structure, reprogrammability, shorter wavelength, smaller device features, anisotropic properties, negative group velocity, non-reciprocity and efficient tunability by various external stimuli to name a few. Hence, despite being a young research field, magnonics has come a long way since its early inception. This roadmap asserts a milestone for future emerging research directions in magnonics, and hopefully, it will inspire a series of exciting new articles on the same topic in the coming years.

11.
Arch Virol ; 166(3): 881-884, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33433694

RESUMEN

In the present study, we serosurveyed the exposure of 222 draft horses to different arboviruses in the city of Santa Fe, Argentina. Plaque reduction neutralization tests confirmed exposure to Fort Sherman virus (FSV), Saint Louis encephalitis virus (SLEV), West Nile virus (WNV), and Río Negro virus (RNV). Apparently, Western and Eastern equine encephalitis viruses did not circulate in the population tested. The confirmation of five seroconversions for WNV, FSV, and SLEV and the association between prevalence and age are indicative of recent circulation. These results highlight the importance of considering draft horses in arboviral surveillance in urban and rural areas of developing countries.


Asunto(s)
Infecciones por Alphavirus/epidemiología , Anticuerpos Antivirales/sangre , Infecciones por Bunyaviridae/epidemiología , Encefalitis de San Luis/epidemiología , Enfermedades de los Caballos/epidemiología , Fiebre del Nilo Occidental/epidemiología , Alphavirus/inmunología , Alphavirus/aislamiento & purificación , Infecciones por Alphavirus/veterinaria , Animales , Argentina/epidemiología , Infecciones por Bunyaviridae/veterinaria , Virus de la Encefalitis de San Luis/inmunología , Virus de la Encefalitis de San Luis/aislamiento & purificación , Encefalitis de San Luis/veterinaria , Enfermedades de los Caballos/virología , Caballos , Orthobunyavirus/inmunología , Orthobunyavirus/aislamiento & purificación , Seroconversión , Fiebre del Nilo Occidental/veterinaria , Virus del Nilo Occidental/inmunología , Virus del Nilo Occidental/aislamiento & purificación
12.
Avian Dis ; 65(4): 530-540, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-35068095

RESUMEN

The emergence of avian reovirus variant strains has caused negative effects in the poultry industry worldwide. Regardless of the efforts in molecular characterization and classification of these variants, information about the pathogenicity, transmissibility, and immunosuppression in chickens is limited. The genomes of two variant strains (A and B) and a classic S1133 strain (C) belonging to the same sigma C genotype 1 were compared. Additionally, these strains were used in a challenge experiment to evaluate inoculated and indirectly exposed specific-pathogen-free chickens. The whole-genome sequence analysis of the three strains revealed nucleotide identity differences in the L3, M2, and S1 genes. Strains A and B also showed homology differences in the S4 gene, despite having high homologies in all other genes. The in vivo challenge experiments showed that, whereas variant A induced high viral loads in tendons, hearts, and duodena of inoculated chickens, variant B induced high viral loads in indirectly exposed chickens. Likewise, histopathology reflected differences in the pathologic effects induced by these strains. For instance, the B and C strains induced more severe microscopic lesions compared with the A strain. Lymphoid depletion was more severe in bursas than in thymi, and inoculated birds were more affected than exposed birds. In conclusion, different pathologic outcomes in chickens were observed depending on the strain and transmission route. This study provides insights onto the relationship between pathogenicity and genomic composition of avian reoviruses.


Reovirus aviares del mismo genotipo inducen diferentes patologías en pollos. La aparición de cepas variantes del reovirus aviar ha causado efectos negativos en la industria avícola en todo el mundo. Independientemente de los esfuerzos en la caracterización molecular y clasificación de estas variantes, la información sobre la patogenicidad, transmisibilidad e inmunodepresión en pollos es limitada. Se compararon los genomas de dos cepas variantes (A y B) y una cepa S1133 clásica (C) perteneciente al mismo genotipo 1 del gene sigma C. Además, estas cepas se utilizaron en un experimento de desafío para evaluar pollos libres de patógenos específicos inoculados y expuestos indirectamente. El análisis de la secuencia del genoma completo de las tres cepas reveló diferencias de identidad de nucleótidos en los genes L3, M2 y S1. Las cepas A y B también mostraron diferencias de homología en el gene S4, a pesar de tener altas similitudes en todos los demás genes. Los experimentos de exposición in vivo mostraron que, mientras que la variante A inducía altas cargas virales en tendones, corazones y duodeno en los pollos inoculados, la variante B inducía altas cargas virales en pollos expuestos indirectamente. Asimismo, la histopatología reflejó diferencias en los efectos patológicos inducidos por estas cepas. Por ejemplo, las cepas B y C indujeron lesiones microscópicas más graves en comparación con la cepa A. La despoblación linfoide fue más severa en las bolsas que en el timo, y las aves inoculadas resultaron más afectadas que las expuestas. En conclusión, se observaron diferentes resultados patológicos en pollos según la cepa y la vía de transmisión. Este estudio proporciona información sobre la relación entre la patogenicidad y la composición genómica de los reovirus aviares.


Asunto(s)
Orthoreovirus Aviar , Enfermedades de las Aves de Corral , Infecciones por Reoviridae , Animales , Pollos , Genotipo , Orthoreovirus Aviar/genética , Infecciones por Reoviridae/veterinaria
13.
Avian Dis ; 65(4): 584-591, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-35068102

RESUMEN

Infectious bronchitis virus (IBV) causes severe economic losses among chicken flocks worldwide. Although IBV molecular surveillance has been conducted in California broilers, seasonal and spatial-temporal trends in IBV prevalence are poorly defined. The goals of this study were to evaluate seasonal and spatial-temporal trends in IBV prevalence and to determine the predominant IBV genotypes obtained over the last 8 yr from a broiler company located in the California Central Valley. In total, 3439 broilers with a suspicion of IBV infection were submitted to the California Animal Health and Food Safety laboratories between January 2012 and February 2020. Swabs from tracheas, kidneys, and cecal tonsils from each submission were independently pooled and screened for IBV using reverse transcriptase quantitative PCR (RT-qPCR). Positive samples were submitted for virus isolation. Viral isolates were subject to a conventional RT-PCR targeting the S1 gene hypervariable region. Positive samples from this RT-PCR were sequenced, and phylogenetic analyses were performed. In total, 1243 pooled swab samples were positive for IBV. Positive results were more frequently detected in fall and winter months compared to spring. Spatial analyses revealed an IBV hot spot in the vicinity of Livingston, and two areas with a low prevalence (i.e., cold spots) around Riverdale. The IBV spatial-temporal distribution identified three significant clusters: one hot spot around Turlock from 2015 to 2016, a second hot spot around Merced from 2012 to 2016, and a cold spot around Fresno from 2017 to 2020. Predominant genotypes changed over time from IBV Cal 99, which was predominant between 2012 and 2014, to IBV 3099 in 2019. Vaccination efforts were initiated in 2018, and as a result, we detected an emerging variant with 92% similarity to CA 3099 in 2020. This work highlights the importance of ongoing surveillance in IBV prevention programs. Surveillance strategies are necessary to monitor trends in diseases such as infectious bronchitis, and the tools used for surveillance need to be sensitive enough to detect new variants and identify spatial-temporal trends.


Vigilancia del virus de la bronquitis infecciosa en pollos de engorde en California (2012­2020). El virus de la bronquitis infecciosa (IBV) causa graves pérdidas económicas entre las parvadas de pollos en todo el mundo. Aunque la vigilancia molecular del virus de la bronquitis infecciosa se ha realizado en pollos de engorde en el estado de California, las tendencias estacionales y espacio-temporales sobre la prevalencia de este virus están mal definidas. Los objetivos de este estudio fueron evaluar las tendencias estacionales y espacio-temporales sobre la prevalencia del virus de la bronquitis infecciosa y determinar los genotipos predominantes de este virus obtenidos durante los últimos ocho años de una empresa de pollos de engorde ubicada en el Valle Central de California. En total, 3439 pollos de engorde con sospecha de infección por el virus de la bronquitis infecciosa se enviaron a los laboratorios de Salud Animal y Seguridad Alimentaria del estado de California entre enero del 2012 y febrero del 2020. Los hisopos de tráqueas, riñones y tonsilas cecales de cada caso se combinaron de forma independiente y se examinaron para detectar al virus de la bronquitis utilizando transcripción reversa y un método cuantitativo de PCR (RT-qPCR). Se enviaron muestras positivas para aislamiento del virus. Los aislados virales se sometieron a un método convencional de RT-PCR dirigido a la región hipervariable del gene S1. Se secuenciaron muestras positivas mediante la prueba RT-PCR y se realizaron análisis filogenéticos. Un total de 1243 muestras combinadas de hisopos dieron positivo para el virus de la bronquitis infecciosa. Los resultados positivos se detectaron con mayor frecuencia en los meses de otoño e invierno en comparación con la primavera. Los análisis espaciales revelaron un punto activo para el virus de la bronquitis infecciosa en las cercanías de Livingston y dos áreas con una baja prevalencia (es decir, puntos fríos) alrededor de Riverdale. La distribución espacio-temporal del virus de la bronquitis identificó tres grupos importantes: un punto activo alrededor de Turlock entre los años 2015 a 2016, un segundo punto activo alrededor de Merced entre los años 2012 a 2016 y un punto frío alrededor de Fresno entre los años 2017 a 2020. Los genotipos predominantes cambiaron con el tiempo, consideraron el subtipo IBV Cal 99, que fue predominante entre 2012 y 2014, a el tipo IBV 3099 en 2019. Los esfuerzos de vacunación se iniciaron en el 2018, y como resultado, detectamos una variante emergente con un 92% de similitud con el virus CA 3099 en 2020. Este trabajo destaca la importancia de la vigilancia continua en los programas de prevención para la bronquitis infecciosa. Las estrategias de vigilancia son necesarias para monitorear las tendencias en enfermedades como la bronquitis infecciosa, y las herramientas utilizadas para la vigilancia deben ser lo suficientemente sensibles como para detectar nuevas variantes e identificar tendencias espacio-temporales.


Asunto(s)
Infecciones por Coronavirus , Virus de la Bronquitis Infecciosa , Enfermedades de las Aves de Corral , Animales , Pollos , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/veterinaria , Filogenia
14.
Avian Dis ; 64(2): 157-165, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32550616

RESUMEN

The reemergence of infectious coryza (IC) caused by Avibacterium paragallinarum (AP) as an acute and occasionally chronic respiratory disease in domestic poultry has caused severe losses in several U.S. states. The disease is also associated with decreased egg production in layers and increased condemnations from air sac infections in broilers. A series of applied experiments were performed to elucidate the persistence of AP in infected broiler flocks, to genotype AP strains isolated from field cases, and to evaluate commercial and autogenous vaccine protection in commercial and specific-pathogen-free (SPF) chickens. Experimental evaluation of environmental persistence suggests that AP did not persist more than 12 hr in a hypothetically contaminated environment. Additionally, other detected potential pathogens such as Gallibacterium anatis and infectious bronchitis virus caused mild respiratory signs in the exposed birds. The HMTp210 and HagA genes of four IC field strains were sequenced and compared with published sequences of HMTp210 and HagA. The HMTp210 phylogeny showed a marginally imperfect clustering of the sequences in genogroups A, B, and C. Although not definitive, this phylogeny provided evidence that the four field strains aligned with previously characterized serovar C strains. Moreover, the base pair homology of the four strains was 100% identical to serovar C reference strains (H-18 and Modesto). HagA phylogeny was unclear, but interestingly, the IC field strains were 100% homologous to C-1 strains reported from Mexico and Ecuador. Finally, vaccine protection studies in commercial hens indicate that clinical signs are induced by a combination of IC and other concomitant pathogens infecting commercial birds. Additionally, vaccine protection experiments performed in SPF hens indicated that protection provided by the two commercial vaccines tested provided a reduction in clinical signs and bacterial shedding after two applications.


Coriza infecciosa: Persistencia, genotipificación y pruebas para vacunas. El resurgimiento de la coriza infecciosa (CI) causada por Avibacterium paragallinarum (AP) como una enfermedad respiratoria aguda y ocasionalmente crónica en aves domésticas ha causado graves pérdidas en varios estados de los Estados Unidos. La enfermedad también se asocia con una disminución en la producción de huevo en gallinas de postura y al incremento de decomisos por infecciones de los sacos aéreos en pollos de engorde. Se realizó una serie de experimentos aplicados para dilucidar la persistencia de A. paragillanarum en parvadas de pollos de engorde infectados, para genotipificar las cepas de A. paragallinarum aisladas de casos de campo y para evaluar la protección de vacunas comerciales y autógenas en pollos comerciales y en aves libres de patógenos específicos (SPF). La evaluación experimental de la persistencia ambiental sugiere que A. paragallinarum no persistió más de doce horas en un ambiente hipotéticamente contaminado. Además, otros patógenos potenciales detectados como Gallibacterium anatis y el virus de la bronquitis infecciosa causaron signos respiratorios leves en las aves expuestas. Los genes HMTp210 y HagA de cuatro cepas de campo de coriza infecciosa se secuenciaron y compararon con las secuencias publicadas de HMTp210 y HagA. La filogenia de HMTp210 mostró una agrupación marginalmente imperfecta de las secuencias en los genogrupos A, B y C. Aunque no es definitiva, esta filogenia proporcionó evidencia de que las cuatro cepas de campo se alinearon con cepas del serovar C previamente caracterizadas. Además, la homología de pares de bases de las cuatro cepas fue 100% idéntica a las cepas de referencia del serovar C (H-18 y Modesto). La filogenia de HagA no fue clara, pero curiosamente, las cepas de campo de coriza infecciosa fueron 100% similares con las cepas C-1 reportadas en México y Ecuador. Finalmente, los estudios de protección de vacunas en gallinas comerciales indican que los signos clínicos son inducidos por una combinación de coriza infecciosa y otros patógenos concomitantes que infectan a las aves comerciales. Además, los experimentos de protección de vacunas realizados en aves libres de patógenos específicos indicaron que la protección proporcionada por las dos vacunas comerciales analizadas proporcionó una reducción en los signos clínicos y en la eliminación bacteriana después de dos aplicaciones.


Asunto(s)
Vacunas Bacterianas/administración & dosificación , Pollos , Genotipo , Infecciones por Haemophilus/veterinaria , Haemophilus paragallinarum/fisiología , Enfermedades de las Aves de Corral/prevención & control , Vacunación/veterinaria , Animales , Femenino , Infecciones por Haemophilus/microbiología , Infecciones por Haemophilus/prevención & control , Haemophilus paragallinarum/inmunología , Enfermedades de las Aves de Corral/microbiología , Organismos Libres de Patógenos Específicos
15.
Plant Dis ; 103(9): 2184-2190, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31287372

RESUMEN

Little cherry disease (LCD) threatens the long-term economic sustainability of the Pacific Northwest sweet cherry (Prunus avium) industry. Results from a series of partial budget analyses indicate that additional investments in monitoring, testing, spraying to control for insect vectors, and removing infected trees are lower than the reduced profit losses compared with the do-nothing scenario. Also, management can prevent or lessen the negative impacts of higher little cherry virus (Velarivirus little cherry virus 1, Ampelovirus little cherry virus 2) spread rates. Our findings illustrate the importance of prevention, correct identification, and controlling for insect vectors in preventing the dissemination of LCD, for which the only known treatment is tree removal.


Asunto(s)
Agricultura , Closteroviridae , Enfermedades de las Plantas , Prunus avium , Agricultura/métodos , Animales , Closteroviridae/fisiología , Frutas , Control de Insectos , Insectos Vectores/fisiología , Enfermedades de las Plantas/prevención & control , Prunus avium/virología , Washingtón
16.
Sci Rep ; 9(1): 9351, 2019 06 27.
Artículo en Inglés | MEDLINE | ID: mdl-31249323

RESUMEN

This study focuses on virus isolation of avian reoviruses from a tenosynovitis outbreak between September 2015 and June 2018, the molecular characterization of selected isolates based on partial S1 gene sequences, and the full genome characterization of seven isolates. A total of 265 reoviruses were detected and isolated, 83.3% from tendons and joints, 12.3% from the heart and 3.7% from intestines. Eighty five out of the 150 (56.6%) selected viruses for sequencing and characterization were successfully detected, amplified and sequenced. The characterized reoviruses grouped in six distinct genotypic clusters (GC1 to GC6). The most represented clusters were GC1 (51.8%) and GC6 (24.7%), followed by GC2 (12.9%) and GC4 (7.2%), and less frequent GC5 (2.4%) and GC3 (1.2%). A shift on cluster representation throughout time occurred. A reduction of GC1 and an increase of GC6 classified strains was noticed. The highest homologies to S1133 reovirus strain were detected in GC1 (~77%) while GC2 to GC6 homologies ranged between 58.5 and 54.1%. Over time these homologies have been maintained. Seven selected isolates were full genome sequenced. Results indicated that the L3, S1 and M2 genes, coding for proteins located in the virus capsid accounted for most of the variability of these viruses. The information generated in the present study helps the understanding of the epidemiology of reoviruses in California. In addition, provides insights on how other genes that are not commonly studied add variability to the reovirus genome.


Asunto(s)
Enfermedades Transmisibles Emergentes/epidemiología , Enfermedades Transmisibles Emergentes/virología , Variación Genética , Genotipo , Orthoreovirus Aviar/genética , Enfermedades de las Aves de Corral/epidemiología , Enfermedades de las Aves de Corral/virología , Infecciones por Reoviridae/veterinaria , Animales , California/epidemiología , Pollos/virología , Genes Virales , Genoma Viral , Orthoreovirus Aviar/aislamiento & purificación , Filogenia , Vigilancia en Salud Pública , Análisis de Secuencia de ADN
17.
Phys Rev Lett ; 122(6): 067204, 2019 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-30822086

RESUMEN

Periodically patterned metamaterials are known for exhibiting wave properties similar to the ones observed in electronic band structures in crystal lattices. In particular, periodic ferromagnetic materials are characterized by the presence of bands and band gaps in their spin-wave spectrum at tunable GHz frequencies. Recently, the fabrication of magnets hosting Dzyaloshinskii-Moriya interactions has been pursued with high interest since properties, such as the stabilization of chiral spin textures and nonreciprocal spin-wave propagation, emerge from this antisymmetric exchange coupling. In this context, to further engineer the magnon band structure, we propose the implementation of magnonic crystals with periodic Dzyaloshinskii-Moriya interactions, which can be obtained, for instance, via patterning of periodic arrays of heavy metal wires on top of an ultrathin magnetic film. We demonstrate through theoretical calculations and micromagnetic simulations that such systems show an unusual evolution of the standing spin waves around the gaps. We also predict the emergence of indirect gaps and flat bands, effects that depend on the strength of the Dzyaloshinskii-Moriya interaction. Such phenomena, which have been previously observed in different systems, are observed here simultaneously, opening new routes towards engineered metamaterials for spin-wave-based devices.

18.
Neurologia (Engl Ed) ; 34(4): 215-223, 2019 May.
Artículo en Inglés, Español | MEDLINE | ID: mdl-28347577

RESUMEN

INTRODUCTION: Obstetric brachial plexus palsy (OBPP) usually has a favourable prognosis. However, nearly one third of all severe cases have permanent sequelae causing a high level of disability. In this study, we explore the effectiveness of ultrasound-guided injection of botulinum toxin A (BoNT-A) and describe the procedure. PATIENTS AND METHODS: We designed a prospective, descriptive study including patients with moderate to severe OBPP who were treated between January 2010 and December 2014. We gathered demographic data, type of OBPP, and progression. Treatment effectiveness was assessed with the Active Movement Scale (AMS), the Mallet classification, and video recordings. RESULTS: We gathered a total of 14 133 newborns, 15 of whom had OBPP (1.6 per 1000 live births). Forty percent of the cases had severe OBPP (0.4/1000), a dystocic delivery, and APGAR scores < 5; mean weight was 4038g. Mean age at treatment onset was 11.5 months. The muscles most frequently receiving BoNT-A injections were the pronator teres, subscapularis, teres major, latissimus dorsi, and pectoralis major. All the patients who completed the follow-up period (83%) experienced progressive improvements: up to 3 points on the AMS and a mean score of 19.5 points out of 25 on the Mallet classification at 2 years. Treatment improved muscle function and abnormal posture in all cases. Surgery was avoided in 3 patients and delayed in one. Adverse events were mild and self-limited. CONCLUSIONS: Due to its safety and effectiveness, BoNT-A may be used off-label as an adjuvant to physical therapy and/or surgery in moderate to severe OBPP. Ultrasound may increase effectiveness and reduce adverse effects.


Asunto(s)
Toxinas Botulínicas Tipo A/administración & dosificación , Neuropatías del Plexo Braquial/tratamiento farmacológico , Toxinas Botulínicas Tipo A/efectos adversos , Neuropatías del Plexo Braquial/diagnóstico por imagen , Neuropatías del Plexo Braquial/fisiopatología , Femenino , Humanos , Lactante , Recién Nacido , Movimiento/fisiología , Embarazo , Estudios Prospectivos , Rango del Movimiento Articular , Resultado del Tratamiento , Ultrasonografía
20.
Prev Vet Med ; 158: 129-136, 2018 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-30220386

RESUMEN

In order to better understand collaboration among trainers in the backyard poultry community (i.e. feed store managers, youth development programs (i.e. 4-H), veterinarians, government agencies, extension resources and backyard poultry club leaders), Social Network Analysis (SNA) was used as a tool to better characterize and quantify the current collaboration network structure of backyard poultry trainers in California. Invited trainer attendees of two "Train-the-Trainers" poultry workshops (n = 67) held in Northern and Southern California were given a survey that asked them to list contacts that they collaborated with on backyard poultry (BYP) related work. The collaboration network in this study included a total of 109 trainers, 18 practitioners, and 32 individuals who are both trainers and practitioners for a total of 170 nodes (11 individuals did not have affiliation information available). In order to help identify central actors or collaboration leaders, the surveys were analyzed using Social Network Analysis (SNA), which allows for a quantitative analysis of relationships among various stakeholders. While the SNA showed that the existing collaboration network is disconnected with a clustering coefficient of 0.043 and median total degree centrality of 1 (range 9) and therefore not conducive for collaboration, key insights that could help restructure and improve the network were identified. As an example, among different poultry groups, 4-H was identified as the organization with the second highest median coverage score and fifth highest median centrality score. In addition, 4-H group leaders act as both trainers and practitioners. Consequently, outreach to 4-H group leaders throughout the state would potentially have the greatest impact with respect to overall coverage both inside and outside the 4-H network due to their high centrality and boundary spanning roles. Using SNA to strengthen the collaboration network infrastructure of backyard poultry trainers ultimately offers a more targeted approach toward extension for backyard poultry owners, which could ultimately facilitate communication and knowledge-sharing with BYP owners during a disease outbreak.


Asunto(s)
Crianza de Animales Domésticos/métodos , Difusión de la Información , Aves de Corral , Apoyo Social , Animales , California , Humanos
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