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The disease caused by the influenza virus is a global public health problem due to its high rates of morbidity and mortality. Thus, analysis of the information generated by epidemiological surveillance systems has vital importance for health decision making. A retrospective analysis was performed using data generated by the four molecular diagnostic laboratories of the Mexican Social Security Institute between 2010 and 2016. Demographics, influenza positivity, seasonality, treatment choices and vaccination status analyses were performed for the vaccine according to its composition for each season. In all cases, both the different influenza subtypes and different age groups were considered separately. The circulation of A/H1N1pdm09 (48.7%), influenza A/H3N2 (21.1%), influenza B (12.6%), influenza A not subtyped (11%) and influenza A/H1N1 (6.6%) exhibited well-defined annual seasonality between November and March, and there were significant increases in the number of cases every 2 years. An inadequate use of oseltamivir was determined in 38% of cases, and the vaccination status in general varied between 12.1 and 18.5% depending on the season. Our results provide current information about influenza in Mexico and demonstrate the need to update both operational case definitions and medical practice guidelines to reduce the inappropriate use of antibiotics and antivirals.
Recently, great attention has been directed towards the use of essential oils from aromatic plants as antimicrobials and antioxidant in food matrix. Fish is well known to be a high perishable food. Indeed, fish muscle is susceptible to suffer protein and lipid oxidation during frozen storage, which can lead to the development of softening and undesirable volatile molecules. However, the possible inclusion of essential oils in fish feed for preserving fish flesh quality during storage is still unclear. For this reason, the potential protective effects of the incorporation of a dietary essential oil constituted by eucalyptol, carvacrol and thymol, to rainbow trout’s (Oncorhynchus mykiss) feed were here investigated. Frozen fish fillets resulting from trout fed the essential oil showed a significant protection of specific muscle proteins against the oxidation produced during frozen storage at –10ºC for 6 months. Essential oil-enriched feed decreased carbonylation of specific myofibrillar (α-actinins-1 and -3, myosin heavy chain, myomesin-1, pyruvate kinase, tropomyosin, troponin-T and actin) and sarcoplasmic proteins (glycogen phosphorylase, creatine kinase, fructose-bisphosphate aldolase A and phosphoglycerate mutase 2). Essential oils also increased actin stability and preserved muscle protein solubility and water holding capacity. In addition, essential oils inhibited the onset of lipid oxidation and rancidity, resulting in frozen fish with superior textural quality and sensory scores. As a final conclusion, the inclusion of essential oils in farmed rainbow trout feed is largely efficient for increasing fish quality and shelf life during frozen storage, mainly through a selective-antioxidant effect on muscle proteins.
The present research studied the effect of a dietary inclusion with Hermetia illucens larvae meal (Hi) on rainbow trout’s fillets chemical composition. The effect of Hi inclusion in diets on rainbow trout chemical characteristics was evaluated. Trout were fed three different diets: control (C, no Hi inclusion), 25% and 50% of substitution of fish meal with Hi (Hi25 and Hi50, respectively). Fillets were analysed to quantify proximate composition, carbohydrates percentage, colour parameters, nucleotides concentration, fatty acids profile, volatile organic compounds (VOCs) and myofibrillar and sarcoplasmic concentrations. Diets did not affect proximate composition. Contrariwise, Hi50 diet decreased fillet yellowness and both substitution percentages affected negatively adenosine monophosphate concentration. Saturated fatty acids, mostly C12 : 0, increased their contents in relation with Hi inclusion at the expense of monounsaturated and polyunsaturated (both n-3 and n-6) fatty acids. Less modifications were reported in VOCs as only heptanal and octanal concentrations were affected, no new compounds appeared in relation with Hi inclusion. No modifications in proteins patterns were shown even if myofibrillar content decreased in trout fed Hi50. The results highlighted that chemical modifications occurred in fillets were related to the chemical composition of the H. illucens meal and to the percentage of inclusion in the diet. Substitution of fish meal with a precisely percentage of H. illucens meal could be a potential future solution in order to decrease the quantity of fish meal used in aquafeeds.
Due to the rapid advance of the emergence of resistant microorganisms to different antibiotics, there is a need to create new antimicrobial agents. It is possible that Nanotechnology has a great impact in this area since the nanoparticles can improve the antimicrobial effect of the antibiotics. In this study we used three different metal oxides nanoparticles, the MgO, ZnO and CuO. These nanoparticles were selected because their interactions leading to cell death and their optical properties. The aim of this study is to develop new methods that are more effective against resistance bacteria, developing antibacterial agents using different nanoparticles against Escherichia coli (ATCC 10536), Pseudomonas aeruginosa (ATCC 10145), and Staphylococcus aureus (ATCC BAA-1026). This study was conducted to evaluate the antibacterial effects of a combination of nanoparticles together with different concentrations of three antibiotics, Gentamicin, Cephalexin and Co-Trimoxazole. The results showed that some nanoparticles are effective to inhibit growth in these microorganisms by increasing the effectiveness of the antibiotic. Therefore, the present study indicates that the combination of the nanoparticles with antibiotics may be applicable as a new antimicrobial agent.
The effects of two aphidophagous predators, the larvae of Chrysoperla carnea and adults of Adalia bipunctata, on the spread of cucumber mosaic virus (CMV) transmitted in a non-persistent manner by the cotton aphid Aphis gossypii were studied under semi-field conditions. Natural enemies and aphids were released inside insect-proof cages (1 m ×1 m ×1 m) with a central CMV-infected cucumber plant surrounded by 48 healthy cucumber seedlings, and the spatiotemporal dynamics of the virus and vector were evaluated in the short and long term (1 and 5 days) in the presence and absence of the natural enemy. The spatial analysis by distance indices methodology together with other indices measuring the dispersal around a single focus was used to assess the spatial pattern and the degree of association between the virus and its vector. Both natural enemies significantly reduced the number of aphids in the CMV-source plant after 5 days but not after 1 day. The CMV transmission rate was generally low, especially after 1 day, due to the limited movement of aphids from the central CMV-source plant, which increased slightly after 5 days. Infected plants were mainly located around the central virus-infected source plant, and the percentage of aphid occupation and CMV-infected plants did not differ significantly in absence and presence of natural enemies. The distribution patterns of A. gossypii and CMV were only coincident close to the central plant. The complexity of multitrophic interactions and the role of aphid predators in the spread of CMV are discussed.
Although variation in the long-term course of major depressive disorder (MDD) is not strongly predicted by existing symptom subtype distinctions, recent research suggests that prediction can be improved by using machine learning methods. However, it is not known whether these distinctions can be refined by added information about co-morbid conditions. The current report presents results on this question.
Data came from 8261 respondents with lifetime DSM-IV MDD in the World Health Organization (WHO) World Mental Health (WMH) Surveys. Outcomes included four retrospectively reported measures of persistence/severity of course (years in episode; years in chronic episodes; hospitalization for MDD; disability due to MDD). Machine learning methods (regression tree analysis; lasso, ridge and elastic net penalized regression) followed by k-means cluster analysis were used to augment previously detected subtypes with information about prior co-morbidity to predict these outcomes.
Predicted values were strongly correlated across outcomes. Cluster analysis of predicted values found three clusters with consistently high, intermediate or low values. The high-risk cluster (32.4% of cases) accounted for 56.6–72.9% of high persistence, high chronicity, hospitalization and disability. This high-risk cluster had both higher sensitivity and likelihood ratio positive (LR+; relative proportions of cases in the high-risk cluster versus other clusters having the adverse outcomes) than in a parallel analysis that excluded measures of co-morbidity as predictors.
Although the results using the retrospective data reported here suggest that useful MDD subtyping distinctions can be made with machine learning and clustering across multiple indicators of illness persistence/severity, replication with prospective data is needed to confirm this preliminary conclusion.
To investigate the genetic diversity and structure of Jatropha curcas L. oilseed plant, in this study, native populations from Chiapas, Mexico, were evaluated, using microsatellite DNA markers. A total of 93 representative samples were selected from seven sites in two regions in the state of Chiapas grouped by geographical proximity, where leaf samples were collected to isolate the genomic DNA. Individual polymerase chain reactions were carried out with ten pairs of specific oligonucleotides for the microsatellites of J. curcas, separating the products of amplification by acrylamide electrophoresis. Twenty-seven fragments were detected (77% polymorphic) with which heterozygous individuals were distinguished. The most informative microsatellite was Jcps20 (nine alleles, polymorphic index content 0.354). The average polymorphism per population was 58%. The Hardy–Weinberg tests revealed a reproductive pattern of non-random mating. The diversity descriptors and the analysis of molecular variance revealed that the populations were structured and moderately differentiated (FST 0.087) and that this differentiation was not due to isolation by distance, as the Mantel test was not significant (P= 0.137), but rather due to allopatry. Bayesian analysis revealed that the accessions belonged to only four genetic groups and confirmed the differentiation between the regions. Because some loci were in Hardy–Weinberg disequilibrium, it is proposed that differentiation is due to the clonal reproduction of J. curcas practised by farmers in Chiapas, along with the anthropogenic dispersion at regional levels. The results of this study reveal that J. curcas in Chiapas has genetic diversity that is greater than that reported in other parts of the world, which represents a potential germplasm pool for the selection of genotypes.
Alfalfa is a model plant defined as less sensitive than others to iron (Fe) deficiency. In the present work, some mechanisms induced in low Fe availability conditions were studied, including the effect of inoculation of alfalfa seeds with Pseudomonas putida. The effect of different Fe contents in the nutrient solution on the growth parameters was evaluated at 3 and 10 days, observing that low Fe conditions promoted biomass accumulation. Activation in the mechanisms of Fe acquisition, through acidification of the media and an increase in the ferric chelate reductase (FCR) activity, was observed in the absence of Fe at 10 days. The presence of P. putida KT2442 in the rhizosphere eliminated FCR activation through the excretion of siderophores. The effect of the siderophores on the modulation of FCR activity was demonstrated using a ppsD mutant strain, unable to segregate them, observing an activation of the activity similar to that observed in the absence of the bacteria. This, together with the demonstrated mechanisms to increase Fe availability, contributed to the conclusion that alfalfa can be used for recovery programmes of soils with low Fe availability.
The Ba(Ti,Zr)O3 powders was synthesized for many methods because its properties as a piezoelectric, dielectric and ferroelectric material that insert it as an functional material, but there is little information in the studied of its optical properties. In this work Ba(Ti,Zr)O3films were produced by ultrasonic spray pyrolysis method for optical applications. The precursors used were an barium acetyl-acetonate, titanium acetyl-acetonate, and zirconium acetyl-acetonate powders dissolved in a N-N, dimethylformamide solution. Optical and morphological properties of the films shown a non crystalline structure and its emission spectra shown a broad and intense luminescence at 468nm which correspond to visible emission in the green region.
The breaking strength that can withstand solder is known as resistance welding, low resistance welding will cause a failure of the weld. This study optimized the effect of the main variables in a welding steel proceess on the mechanical propierties of the steel like the resistance welding. The main variables studied were electrode, machine, post induction, and dotted pressure. The factors that have the most influence in the resistance welding are the post induction, and the combination of post induction and the raw material.The statistical model used for the evaluation process was an analysis of variance (ANOVA) in a full crossing factorial design 2k with a second order of interaction.