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1.
Lett Appl Microbiol ; 75(3): 680-688, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35687297

RESUMO

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.


Assuntos
Nanopartículas Metálicas , Infecções por Pseudomonas , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Farmacorresistência Bacteriana Múltipla , Humanos , Levofloxacino/farmacologia , Levofloxacino/uso terapêutico , Meropeném/farmacologia , Testes de Sensibilidade Microbiana , Extratos Vegetais/farmacologia , Infecções por Pseudomonas/tratamento farmacológico , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa , Espécies Reativas de Oxigênio , Prata/farmacologia
2.
Arch Virol ; 166(3): 881-884, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33433694

RESUMO

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.


Assuntos
Infecções por Alphavirus/epidemiologia , Anticorpos Antivirais/sangue , Infecções por Bunyaviridae/epidemiologia , Encefalite de St. Louis/epidemiologia , Doenças dos Cavalos/epidemiologia , Febre do Nilo Ocidental/epidemiologia , Alphavirus/imunologia , Alphavirus/isolamento & purificação , Infecções por Alphavirus/veterinária , Animais , Argentina/epidemiologia , Infecções por Bunyaviridae/veterinária , Vírus da Encefalite de St. Louis/imunologia , Vírus da Encefalite de St. Louis/isolamento & purificação , Encefalite de St. Louis/veterinária , Doenças dos Cavalos/virologia , Cavalos , Orthobunyavirus/imunologia , Orthobunyavirus/isolamento & purificação , Soroconversão , Febre do Nilo Ocidental/veterinária , Vírus do Nilo Ocidental/imunologia , Vírus do Nilo Ocidental/isolamento & purificação
3.
Phys Rev Lett ; 122(6): 067204, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30822086

RESUMO

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.

4.
Plant Dis ; 103(9): 2184-2190, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31287372

RESUMO

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.


Assuntos
Agricultura , Closteroviridae , Doenças das Plantas , Prunus avium , Agricultura/métodos , Animais , Closteroviridae/fisiologia , Frutas , Controle de Insetos , Insetos Vetores/fisiologia , Doenças das Plantas/prevenção & controle , Prunus avium/virologia , Washington
5.
Oral Dis ; 21(4): 451-5, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25421014

RESUMO

OBJECTIVE: The objective of this study was to evaluate the efficacy of two commercial nucleic acid amplification techniques to identify Mycobacterium tuberculosis in saliva. SUBJECTS AND METHODS: Fifty-two participants were recruited, 32 patients with a clinical and microbiological diagnosis of pulmonary tuberculosis and 20 healthy volunteers as controls. Three sputum samples were collected from each participant and were examined by direct bacilloscopy, cultured in liquid and solid media, and processed using the Mycobacterium tuberculosis direct (MTD) test for rRNA detection. One saliva sample was collected from each participant using conventional methods and was examined by direct bacilloscopy, cultured, and processed using the MTD test for rRNA detection and the FluoroType Mycobacterium tuberculosis assay for DNA detection. RESULTS: In saliva samples, the sensitivity, specificity, and positive and negative predictive values of the MTD test were 71.8%, 95%, 95.8%, and 67.8%, respectively. The values obtained with the FluoroType assay were 56.2%, 90%, 90%, and 56.2%, respectively. CONCLUSIONS: Our results indicate that when a sufficient volume of sputum cannot be obtained, saliva could be an alternative biological sample for the rapid diagnosis of pulmonary tuberculosis using commercial nucleic acid amplification techniques.


Assuntos
Mycobacterium tuberculosis/isolamento & purificação , Técnicas de Amplificação de Ácido Nucleico/métodos , Saliva/microbiologia , Tuberculose Pulmonar/diagnóstico , Tuberculose Pulmonar/microbiologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mycobacterium tuberculosis/genética , Reação em Cadeia da Polimerase/métodos , Adulto Jovem
6.
Avian Dis ; 58(2): 211-5, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25055623

RESUMO

Protective properties of three distinct infectious bronchitis virus (IBV) Ark Delmarva poultry industry (ArkDPI) S1 proteins encoded from replication-defective recombinant adenovirus vectors were investigated. Using a suboptimal dose of each recombinant virus, we demonstrated that IBV S1 amino acid sequences showing > or = 95.8% amino acid identity to the S1 of the challenge strain differed in their ability at conferring protection. Indeed, the S1 sequence of the IBV population previously designated C4 (AdIBVS1.C4), which protected the most poorly, differs from the S1 sequence of population C2 (AdIBVS1.C2), which provided the highest protection, only at amino acid position 56. The fact that a change in one amino acid in this region significantly altered the induction of a protective immune response against this protein provides evidence that the first portion of S1 displays relevant immunoprotective epitopes. Use of an optimal dose of AdIBVS1.C2 effectively protected chickens from clinical signs and significantly reduced viral load after IBV Ark virulent challenge. Moreover, increased numbers of both IgA and IgG IBV-specific antibody secreting lymphocytes were detected in the spleen after challenge. The increased response detected for both IgA and IgG lymphocytes after challenge might be explained by vaccine-induced B memory cells. The fact that a single vaccination with Ad/IBVS1.C2 provides protection against IBV challenge is promising, because Ad-vectored vaccines can be mass delivered by in ovo inoculation using automated in ovo injectors.


Assuntos
Galinhas , Infecções por Coronavirus/veterinária , Vírus da Bronquite Infecciosa/imunologia , Doenças das Aves Domésticas/imunologia , Glicoproteína da Espícula de Coronavírus/genética , Vacinas Virais/imunologia , Animais , Infecções por Coronavirus/genética , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/virologia , Vetores Genéticos/genética , Vetores Genéticos/imunologia , Vírus da Bronquite Infecciosa/genética , Doenças das Aves Domésticas/genética , Doenças das Aves Domésticas/virologia , Organismos Livres de Patógenos Específicos , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinas Atenuadas/genética , Vacinas Atenuadas/imunologia , Vacinas Virais/genética
7.
Avian Dis ; 58(4): 579-86, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25619003

RESUMO

Pathogenicity and immune responses were characterized in commercial broilers and layers challenged with very virulent infectious bursal disease virus (vvIBDV) reassortants (vvIBDV segment A + serotype 2 segment B and vvIBDV segment A + classic virulent segment B) at 7 days of age. In addition, functional immunosuppression was evaluated after challenge with infectious bronchitis virus (IBV) at 15 days of age. Layers showed higher levels and increased persistence of IBDV- and IBV-specific maternal antibodies than broilers at 1, 13, and 28 days of age. Cytokine gene expression was evaluated, after IBDV challenge, as an indicator of the innate immune function. Similar results were detected between the groups inoculated with vvIBDV reassortants. Interleukin-1ß (IL-1ß) in the bursa of layers demonstrated down-regulation at 1 day postinfection (DPI; 8 days of age), and no changes at 4 DPI (11 days of age) compared with controls. In broilers, IL-6 expression in the bursa was down-regulated 1 DPI (8 days of age) and up-regulated at 4 DPI (11 days of age). A significant lymphoid depletion was detected at 21 DPI (28 days of age) in broilers exposed to a reassortant of vvIBDV segment A and classic virulent IBDV segment B. Finally, reduced specific antibodies against IBV measured 13 days after challenge were detected in layer and broiler chickens inoculated with a reassortant serotype 2 IBDV in segment B, suggesting functional immunosuppression. These results provide evidence indicating that current IBDV vaccination of breeders does not completely protect progeny chickens from challenge with reassortant vvIBDV.


Assuntos
Infecções por Birnaviridae/veterinária , Galinhas , Vírus da Doença Infecciosa da Bursa/patogenicidade , Animais , Anticorpos Antivirais , Infecções por Birnaviridae/virologia , Imunidade Materno-Adquirida , Masculino , Vírus Reordenados , Virulência
8.
J Food Sci ; 89(2): 1225-1242, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38204401

RESUMO

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.


Assuntos
Benzopiranos , Pyrus , Cloreto de Tolônio , Estados Unidos , Preferências Alimentares , Comportamento do Consumidor , Paladar , Noroeste dos Estados Unidos , Frutas
9.
J Prev Alzheimers Dis ; 11(4): 889-894, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39044498

RESUMO

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.


Assuntos
Doença de Alzheimer , Disseminação de Informação , Humanos , Estudos Longitudinais , Idoso , Neuroimagem , Masculino , Feminino , Ensaios Clínicos Controlados Aleatórios como Assunto , Anticorpos Monoclonais Humanizados
10.
PLoS One ; 17(12): e0270792, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36512609

RESUMO

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.


Assuntos
Comportamento do Consumidor , Vitis , Paladar , Vitis/genética , Edição de Genes , Melhoramento Vegetal
11.
Sci Rep ; 12(1): 17831, 2022 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-36284121

RESUMO

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.

12.
Poult Sci ; 101(11): 102138, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36126448

RESUMO

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.


Assuntos
Doença de Newcastle , Doenças das Aves Domésticas , Feminino , Animais , Vírus da Doença de Newcastle , Galinhas , Gana/epidemiologia , Doenças das Aves Domésticas/prevenção & controle , Doença de Newcastle/prevenção & controle
13.
Foods ; 10(7)2021 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-34359493

RESUMO

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.

14.
J Food Sci ; 86(8): 3658-3671, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34255388

RESUMO

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.


Assuntos
Comportamento do Consumidor , Paladar , Humanos , Micro-Ondas , Pasteurização
15.
Avian Dis ; 65(4): 530-540, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-35068095

RESUMO

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.


Assuntos
Orthoreovirus Aviário , Doenças das Aves Domésticas , Infecções por Reoviridae , Animais , Galinhas , Genótipo , Orthoreovirus Aviário/genética , Infecções por Reoviridae/veterinária
16.
Avian Dis ; 65(4): 584-591, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-35068102

RESUMO

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.


Assuntos
Infecções por Coronavirus , Vírus da Bronquite Infecciosa , Doenças das Aves Domésticas , Animais , Galinhas , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/veterinária , Filogenia
17.
Avian Dis ; 65(3): 373-380, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34427410

RESUMO

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.


Assuntos
Infecções por Coronavirus , Vírus da Bronquite Infecciosa , Doenças das Aves Domésticas , Vacinas Virais , Animais , Galinhas , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/veterinária , Feminino , Vírus da Bronquite Infecciosa/genética , Organismos Livres de Patógenos Específicos
18.
J Phys Condens Matter ; 33(41)2021 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-33662946

RESUMO

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.

19.
Nefrologia ; 30(6): 661-8, 2010.
Artigo em Espanhol | MEDLINE | ID: mdl-21113216

RESUMO

INTRODUCTION: Insulin resistance (IR) increases significantly the risk for cardiovascular disease (CV) in the general population. IR is a common metabolic disorder in patients with chronic kidney disease (CKD). However, the influence of IR on the evolution of CKD patients has scarcely been studied. OBJECTIVE: This study aims to determine whether IR is associated with the progression of CKD, the development of new CV events, or all-cause mortality of non-diabetic patients with CKD stage 4 or 5 not yet on dialysis. MATERIAL AND METHODS: The study group consisted of 365 non-diabetic patients (63 ± 16 year, 169 females) with GFR < 30 ml/min. The degree of IR was estimated by the Homeostasis Model Assessment parameter (HOMA). The outcome measures were: progression of CKD (composite of initiation of dialysis or doubling of baseline serum creatinine level), new cardiovascular events, and all-cause mortality. Unadjusted and multivariable-adjusted relative risks were calculated for HOMA either as a continuous or qualitative variable (tertiles), using Cox proportional hazards models. RESULTS: Mean HOMA value (± SD) was 4.28 ± 2.07. HOMA values correlated significantly with body mass index (beta = 0.37; p < 0.0001), plasma triglycerides (beta = 0.22; p < 0.0001), plasma albumin (beta = 0.19; p = 0.007), and serum phosphate (beta = 0.17; p = 0.031). Progression of CKD was observed in 234 patients (64%) with a median follow-up of 542 days. Patients with HOMA values in the lower tertile (< 3.13) showed a slower progression of CKD than that of the rest of study patients (log rank 4.16, p < 0.05). In adjusted models for age, sex, baseline GFR, body mass index, and proteinuria, HOMA values in the lower tertile entered as an independent variable in the best predictive equation for progression of CKD (HR 0.72, p < 0.03). Fifty-one patients developed a new CV event and 103 patients died during the study period (median follow-up of 1,103 days). HOMA did not relate to the development of new CV events or all-cause mortality in unadjusted or adjusted models for age, sex, comorbid index, plasma albumin, and C-reactive protein. CONCLUSIONS: In conclusion, progression of renal disease was slower in those non-diabetic CKD patients with low HOMA values; however, HOMA values did not relate to the development of new CV events or all-cause mortality.


Assuntos
Resistência à Insulina , Nefropatias/metabolismo , Idoso , Doenças Cardiovasculares/epidemiologia , Doença Crônica , Comorbidade , Progressão da Doença , Feminino , Taxa de Filtração Glomerular , Homeostase , Humanos , Estimativa de Kaplan-Meier , Nefropatias/mortalidade , Masculino , Pessoa de Meia-Idade , Neoplasias/epidemiologia , Prognóstico , Modelos de Riscos Proporcionais , Estudos Prospectivos , Doença Pulmonar Obstrutiva Crônica/epidemiologia
20.
Avian Dis ; 64(2): 157-165, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32550616

RESUMO

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.


Assuntos
Vacinas Bacterianas/administração & dosagem , Galinhas , Genótipo , Infecções por Haemophilus/veterinária , Haemophilus paragallinarum/fisiologia , Doenças das Aves Domésticas/prevenção & controle , Vacinação/veterinária , Animais , Feminino , Infecções por Haemophilus/microbiologia , Infecções por Haemophilus/prevenção & controle , Haemophilus paragallinarum/imunologia , Doenças das Aves Domésticas/microbiologia , Organismos Livres de Patógenos Específicos
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