272 research outputs found
Postharvest heat treatments to inhibit Penicillium digitatum growth and maintain quality of Mandarin (Citrus reticulata blanco)
Use of fungicides is a common practice as a postharvest treatment to control fruit decay. Nowadays, environment-friendly technologies, such as heat treatments, are viable replacements. This study evaluated the effects of post-harvest heat treatments (traditional and microwave-assisted) on mandarins intentionally inoculated with Penicillium digitatum. For the studied heat treatments, the target temperature was 50C, which was held for 2.5 min. After heating, mandarins were cooled and stored at 25C for 13 days. MW treatments effectively prevented mold growth during storage, while HW only delayed it. Control mandarins (without treatment) showed the highest significant weight loss. Neither thermal treatment nor storage affected fruit juice pH (p \u3e 0.05). Treated mandarins had a significantly lower vitamin C content than control fruits throughout storage, and all mandarins lost firmness by the 13th day (p \u3c 0.05). Control and MW-treated mandarins had lower citric acid content; however, they retained color, total soluble solids (TSS) and had a higher maturity index. While HW mandarins did not have changes in citric acid content, they had higher TSS, and lower maturity index. MW-assisted treatments were effective at inactivating molds and helped retain some nutritional and physical-chemical characteristics of mandarins. However, juice of MW-treated mandarins was not preferred by judges in the sensory tests, the juice was rated lower than that obtained from the other treatment. Postharvest heat treatments may constitute a helpful application to control mandarin’ fungal decay
Antimicrobial Activity and Physicochemical Characterization of Oregano, Thyme and Clove Leave Essential Oils, Nonencapsulated and Nanoencapsulated, Using Emulsification
Background and objective: Functional properties of essential oils are attributed to their components, many of which exhibit antimicrobial activity against pathogenic and spoilage microorganisms in a wide variety of foods. However, essential oils are unstable compounds; therefore, they can be encapsulated for a better protection and increase of functionality. In this work, antimicrobial activities of oregano, thyme and clove leave essential oils (non-encapsulated and nanoencapsulated) were assessed against Escherichia coli ATCC 29922, Salmonella typhimurium ATCC 14028 and Staphylococcus aureus ATCC 25923 using emulsification.Material and methods: The essential oils were characterized based on their physicochemical properties. Nanoemulsions were prepared, using 5% (w w-1) of essential oils, and then characterized based on their physical properties, stability and encapsulation efficiency. The microdilution antimicrobial assay was carried out to assess minimum inhibitory concentration and minimum bactericidal concentration of the essential oils and their nanoemulsions. Data from physical properties of the essential oils and physical properties, stability and encapsulation efficiency of the nanoemulsions were statistically analyzed.Results and conclusion: Antimicrobial activity of the essential oils showed decreases in minimum inhibitory concentration by 27-60% for the nanoencapsulated oils, compared to nonencapsulated oils. Nanoencapsulated and nonencapsulated oregano essential oils exhibited the lowest minimum inhibitory concentration and minimum bactericidal concentration values. Based on the results, nanoencapslulated essential oils may further be used in various foods to avoid microbial contaminations.Conflict of interest: The authors declare no conflict of interest
Relaciones tóxicas en jóvenes aragoneses: impacto y consecuencias
Este trabajo se centra en investigar las relaciones de pareja tóxicas entre los jóvenes aragoneses, seleccionando como muestra a los alumnos del Instituto Ítaca de Zaragoza, con el objetivo de conocer su impacto y consecuencias. La violencia de género es una cuestión que está muy presente en nuestra sociedad y que se relaciona con el objeto de este estudio, ya que la hipótesis de partida es que una relación toxica puede desembocar en una futura violencia de género. Para comprobar si la hipótesis es cierta se han consultado diferentes estudios, artículos y libros sobre este tema, al mismo tiempo, se ha realizado una intervención y cuestionario online con los alumnos, con el fin de conocer su visón sobre el maltrato, dependencia emocional y los mitos del amor. Los resultados obtenidos demuestran que los jóvenes no son del todo conscientes de la gravedad de este tema, pero comienzan a ser más sensibles
Human-carnivore relations: conflicts, tolerance and coexistence in the American West
Carnivore and humans live in proximity due to carnivore recovery efforts and ongoing human encroachment into carnivore habitats globally. The American West is a region that uniquely exemplifies these human-carnivore dynamics, however, it is unclear how the research community here integrates social and ecological factors to examine human-carnivore relations. Therefore, strategies promoting human-carnivore coexistence are urgently needed. We conducted a systematic review on human-carnivore relations in the American West covering studies between 2000 and 2018. We first characterized human-carnivore relations across states of the American West. Second, we analyzed similarities and dissimilarities across states in terms of coexistence, tolerance, number of ecosystem services and conflicts mentioned in literature. Third, we used Bayesian modeling to quantify the effect of social and ecological factors influencing the scientific interest on coexistence, tolerance, ecosystem services and conflicts. Results revealed some underlying biases in human-carnivore relations research. Colorado and Montana were the states where the highest proportion of studies were conducted with bears and wolves the most studied species. Non-lethal management was the most common strategy to mitigate conflicts. Overall, conflicts with carnivores were much more frequently mentioned than benefits. We found similarities among Arizona, California, Utah, and New Mexico according to how coexistence, tolerance, services and conflicts are addressed in literature. We identified percentage of federal/private land, carnivore family, social actors, and management actions, as factors explaining how coexistence, tolerance, conflicts and services are addressed in literature. We provide a roadmap to foster tolerance towards carnivores and successful coexistence strategies in the American West based on four main domains, (1) the dual role of carnivores as providers of both beneficial and detrimental contributions to people, (2) social-ecological factors underpinning the provision of beneficial and detrimental contributions, (3) the inclusion of diverse actors, and (4) cross-state collaborative management
Antifungal effect of essential oil components against Aspergillus niger when loaded into silica mesoporous supports
BACKGROUND: Essential oil components (EOCs) are known for their antifungal properties; however, their high volatility limits their application as antimicrobial agents. Strategies used for controlling the volatility of EOCs include encapsulation or loading into porous materials. This study evaluated the in vitro antifungal activity of selected EOCs (carvacrol, cinnamaldehyde, eugenol and thymol) against the fungus Aspergillus niger when loaded into MCM-41 and b-cyclodextrin (b-CD).
RESULTS:
Carvacrol and thymol in Mobil Composition of Matter No. 41 (MCM-41) displayed remarkable enhanced antifungal properties in comparison to the pure or b- CD-encapsulated EOCs. In fact, carvacrol and thymol were able to maintain antifungal activity and inhibit fungal growth for 30 days, suggesting better applicability of these EOCs as natural preservatives.
CONCLUSIONS:
The sustained antifungal effect of EOCs encapsulated into silica mesoporous supports was described.The authors wish to express their gratitude to the Government of the Czech Republic (Postdok CZU: ESF and MEYS CZ.1.07/2.3.00/30.0040), to CIGA (Project number: 20132024) and to the Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic (research project RVO: 61388963). Beth Green is thanked for language control.Bernardos Bau, A.; Marina, T.; Zacek, P.; Pérez-Esteve, É.; Martínez-Máñez, R.; Lhotka, M.; Kourimská, L.... (2015). Antifungal effect of essential oil components against Aspergillus niger when loaded into silica mesoporous supports. Journal of the Science of Food and Agriculture. 95(14):2824-2831. doi:10.1002/jsfa.7022S28242831951
Association between HLA-C alleles and COVID-19 severity in a pilot study with a Spanish Mediterranean Caucasian cohort
The clinical presentations of COVID-19 may range from an asymptomatic or mild infection to a critical or fatal disease. Several host factors such as elderly age, male gender, and previous comorbidities seem to be involved in the most severe outcomes, but also an impaired immune response that causes a hyperinflammatory state but is unable to clear the infection. In order to get further understanding about this impaired immune response, we aimed to determine the association of specific HLA alleles with different clinical presentations of COVID-19. Therefore, we analyzed HLA Class I and II, as well as KIR gene sequences, in 72 individuals with Spanish Mediterranean Caucasian ethnicity who presented mild, severe, or critical COVID-19, according to their clinical characteristics and management. This cohort was recruited in Madrid (Spain) during the first and second pandemic waves between April and October 2020. There were no significant differences in HLA-A or HLA-B alleles among groups. However, despite the small sample size, we found that HLA-C alleles from group C1 HLA-C*08:02, -C*12:03, or -C*16:01 were more frequently associated in individuals with mild COVID-19 (43.8%) than in individuals with severe (8.3%; p = 0.0030; pc = 0.033) and critical (16.1%; p = 0.0014; pc = 0.0154) disease. C1 alleles are supposed to be highly efficient to present peptides to T cells, and HLA-C*12:03 may present a high number of verified epitopes from abundant SARS-CoV-2 proteins M, N, and S, thereby being allegedly able to trigger an efficient antiviral response. On the contrary, C2 alleles are usually poorly expressed on the cell surface due to low association with β2-microglobulin (β2M) and peptides, which may impede the adequate formation of stable HLA-C/β2M/peptide heterotrimers. Consequently, this pilot study described significant differences in the presence of specific HLA-C1 alleles in individuals with different clinical presentations of COVID-19, thereby suggesting that HLA haplotyping could be valuable to get further understanding in the underlying mechanisms of the impaired immune response during critical COVID-19.This work was supported by the Coordinated Research Activities at the Centro Nacional de Microbiologı´a (CNM, Instituto de Salud Carlos III) (COV20_00679) to promote an integrated response against SARS-CoV-2 in Spain (Spanish Ministry of Science and Innovation) that is coordinated by Dr Inmaculada Casas (WHO National Influenza Center of the CNM); donation provided by Chiesi España, S.A.U. (Barcelona, Spain); the Spanish Ministry of Science and Innovation (PID2019-110275RB-I00); and grant MPY509/19 provided by Instituto de Salud Carlos III. The work of MRLH and SRM is financed by NIH grant R01AI143567. The work of LV is supported by a pre-doctoral contract from Instituto de Salud Carlos III (FIS PI16CIII/00034-ISCIII-FEDER). The work of MT is supported by Instituto de Salud Carlos III (COV20_00679). AJMG is the recipient of a post-doctoral contract“Miguel Servet” supported by the Instituto de Salud Carlos III.S
Impaired Cytotoxic Response in PBMCs From Patients With COVID-19 Admitted to the ICU: Biomarkers to Predict Disease Severity
Infection by novel coronavirus SARS-CoV-2 causes different presentations of COVID-19 and some patients may progress to a critical, fatal form of the disease that requires their admission to ICU and invasive mechanical ventilation. In order to predict in advance which patients could be more susceptible to develop a critical form of COVID-19, it is essential to define the most adequate biomarkers. In this study, we analyzed several parameters related to the cellular immune response in blood samples from 109 patients with different presentations of COVID-19 who were recruited in Hospitals and Primary Healthcare Centers in Madrid, Spain, during the first pandemic peak between April and June 2020. Hospitalized patients with the most severe forms of COVID-19 showed a potent inflammatory response that was not translated into an efficient immune response. Despite the high levels of effector cytotoxic cell populations such as NK, NKT and CD8+ T cells, they displayed immune exhaustion markers and poor cytotoxic functionality against target cells infected with pseudotyped SARS-CoV-2 or cells lacking MHC class I molecules. Moreover, patients with critical COVID-19 showed low levels of the highly cytotoxic TCRγδ+ CD8+ T cell subpopulation. Conversely, CD4 count was greatly reduced in association to high levels of Tregs, low plasma IL-2 and impaired Th1 differentiation. The relative importance of these immunological parameters to predict COVID-19 severity was analyzed by Random Forest algorithm and we concluded that the most important features were related to an efficient cytotoxic response. Therefore, efforts to fight against SARS-CoV-2 infection should be focused not only to decrease the disproportionate inflammatory response, but also to elicit an efficient cytotoxic response against the infected cells and to reduce viral replication.This work was supported by the Coordinated Research Activities at the Centro Nacional de Microbiología (CNM, Instituto de Salud Carlos III) (COV20_00679) to promote an integrated response against SARS-CoV-2 in Spain (Spanish Ministry of Science and Innovation) that is coordinated by Dr. Inmaculada Casas (WHO National Influenza Center of the CNM); a generous donation provided by Chiesi España, S.A.U. (Barcelona, Spain); the Spanish Ministry of Economy and Competitiveness (PID2019-110275RB-I00); the Spanish AIDS Research Network RD16CIII/0002/0001 that is included in Acciόn Estratégica en Salud, Plan Nacional de Investigaciόn Científica, Desarrollo e Innovaciόn Tecnolόgica 2016-2020, Instituto de Salud Carlos III, European Region Development Fund (ERDF). The work of ML-H and SR-M is financed by NIH grant R01AI143567. The work of LH is supported by a pre-doctoral grant from Instituto de Salud Carlos III (FIS PI16CIII/00034-ISCIII-FEDER).S
Impaired Antibody-Dependent Cellular Cytotoxicity in a Spanish Cohort of Patients With COVID-19 Admitted to the ICU
SARS-CoV-2 infection causes COVID-19, ranging from mild to critical disease in symptomatic subjects. It is essential to better understand the immunologic responses occurring in patients with the most severe outcomes. In this study, parameters related to the humoral immune response elicited against SARS-CoV-2 were analysed in 61 patients with different presentations of COVID-19 who were recruited in Hospitals and Primary Healthcare Centres in Madrid, Spain, during the first pandemic peak between April and June 2020. Subjects were allocated as mild patients without hospitalization, severe patients hospitalized or critical patients requiring ICU assistance. Critical patients showed significantly enhanced levels of B cells with memory and plasmablast phenotypes, as well as higher levels of antibodies against SARS-CoV-2 with neutralization ability, which were particularly increased in male gender. Despite all this, antibody-dependent cell-mediated cytotoxicity was defective in these individuals. Besides, patients with critical COVID-19 also showed increased IgG levels against herpesvirus such as CMV, EBV, HSV-1 and VZV, as well as detectable CMV and EBV viremia in plasma. Altogether, these results suggest an enhanced but ineffectual immune response in patients with critical COVID-19 that allowed latent herpesvirus reactivation. These findings should be considered during the clinical management of these patients due to the potential contribution to the most severe disease during SARS-CoV-2 infection.This work was supported by the Coordinated Research Activities at the Centro Nacional de Microbiología (CNM, Instituto de Salud Carlos III) (COV20_00679) to promote an integrated response against SARS-CoV-2 in Spain (Spanish Ministry of Science and Innovation) that is coordinated by Dr Inmaculada Casas (WHO National Influenza Center of the CNM) and a generous donation provided by Chiesi España, S.A.U. (Barcelona, Spain). The funder was not involved in the study design, collection, analysis, interpretation of data, the writing of this article or the decision to submit it for publication. This work was also supported by the Spanish Ministry of Economy and Competitiveness (PID2019 110275RB-I00); the Spanish AIDS Research Network RD16CIII/0002/0001 that is included in Acción Estratégica en Salud, Plan Nacional de Investigación Científica, Desarrollo e Innovación Tecnológica 2016-2020, Instituto de Salud Carlos III, European Region Development Fund (ERDF); Miguel Servet - AESI, MPY 341/21. The work of ML-H and SR is financed by NIH grant R01AI143567. The work of MT is supported by Instituto de Salud Carlos III (COV20_00679). The work of LV is supported by a predoctoral grant from Instituto de Salud Carlos III (FIS PI16CIII/00034-ISCIII-FEDER).S
Grain size-dependent magnetic and electric properties in nanosized YMnO3 multiferroic ceramics
Magnetic and electric properties are investigated for the nanosized YMnO3 samples with different grain sizes (25 nm to 200 nm) synthesized by a modified Pechini method. It shows that magnetic and electric properties are strongly dependent on the grain size. The magnetic characterization indicates that with increasing grain size, the antiferromagnetic (AFM) transition temperature increases from 52 to 74 K. A corresponding shift of the dielectric anomaly is observed, indicating a strong correlation between the electric polarization and the magnetic ordering. Further analysis suggests that the rising of AFM transition temperature with increasing grain size should be from the structural origin, in which the strength of AFM interaction as well as the electrical polarization is dependent on the in-plane lattice parameters. Furthermore, among all samples, the sample with grain size of 95 nm is found to have the smallest leakage current density (< 1 μA/cm2)
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