Sitotroga cerealella-resistant mexican maize races (Zea mays L.), new sources of resistance for commercial maize breeding

Sitotroga cerealella (Oliv.) (Lepidoptera: Gelechiidae) is one of the most important post-harvest pests of maize Zea mays L. Some Mexican maize races (Z. mays) could be a novel source of resistance against S. cerealella to improve commercial maize varieties, lines and hybrids. We studied the resistance of Mexican maize races, recollected at Chihuahua State to S. cerealella. We focused on antibiosis and tolerance of maize to S. cerealella. Cristalino-079 maize race shows low level of consumption in grams and percentage, increased larvae mortality before to entering the seed. In addition, Cristalino-079 reduced first adult’s generation and show the largest biological cycle. Due to the small number of emerged adults, there was very little grain weight loss in resistant maize race. The compound that causes high mortality of larvae before to entering the grain is in the pericarp of resistant maize races. The compound that causes longest development time is in the endosperm and embryo. Cristalino-079 show the better level of resistance to S. cerealella infestation in almost all traits studied and this can be used as source of resistance for maize breeding

SARS-CoV-2 Infection in Multiple Sclerosis

To understand COVID-19 characteristics in people with multiple sclerosis (MS) and identify high-risk individuals due to their immunocompromised state resulting from the use of disease-modifying treatments. Retrospective and multicenter registry in patients with MS with suspected or confirmed COVID-19 diagnosis and available disease course (mild = ambulatory; severe = hospitalization; and critical = intensive care unit/death). Cases were analyzed for associations between MS characteristics and COVID-19 course and for identifying risk factors for a fatal outcome. Of the 326 patients analyzed, 120 were cases confirmed by real-time PCR, 34 by a serologic test, and 205 were suspected. Sixty-nine patients (21.3%) developed severe infection, 10 (3%) critical, and 7 (2.1%) died. Ambulatory patients were higher in relapsing MS forms, treated with injectables and oral first-line agents, whereas more severe cases were observed in patients on pulsed immunosuppressors and critical cases among patients with no therapy. Severe and critical infections were more likely to affect older males with comorbidities, with progressive MS forms, a longer disease course, and higher disability. Fifteen of 33 patients treated with rituximab were hospitalized. Four deceased patients have progressive MS, 5 were not receiving MS therapy, and 2 were treated (natalizumab and rituximab). Multivariate analysis showed age (OR 1.09, 95% CI, 1.04-1.17) as the only independent risk factor for a fatal outcome. This study has not demonstrated the presumed critical role of MS therapy in the course of COVID-19 but evidenced that people with MS with advanced age and disease, in progressive course, and those who are more disabled have a higher probability of severe and even fatal diseas

Purification of Porphyromonas gingivalis polysaccharide free lipopolysaccharide using Sephacryl S-200 high resolution chromatography

El objetivo de este trabajo fue mejorar un método estándar para la purificación de lipopolisacárido (LPS) de Porphyromonas gingivalis libre de polisacáridos usando una estrategia de extracción, digestión enzimática y cromatografía de alta resolución. La bacteria P. gingivalis se cultivó en condiciones de anaerobiosis y se hizo extracción de las membranas con el método de fenol-agua. Luego de una digestión enzimática (DNAsa, RNAsa y proteasa) se separó el extracto por filtración por gel con Sephacryl S-200. La muestra purificada se caracterizó por electroforesis en gel de acrilamida con tinción de plata y por el método Purpald se detecto el ácido 2-ceto-3-desoxioctu- losónico (KDO). Se obtuvo una preparación libre de ácidos nucleicos, proteínas y polisacáridos. La separación por cromatografía fue de alta resolución al permitir la obtención de dos picos con diferentes componentes. El protocolo de purificación nos permitió obtener LPS de P. gingivalis con alto grado de pureza, el cual podría ser usado en próximos ensayos para evaluar su función en ensayos in vitro e in vivo; así como iniciar la obtención de LPS de otras bacterias períodontopáticas, con el fin de investigar la asociación de enfermedad períodontal con enfermedades cardiovasculares.The aim of this work was to improve a standard methodology to purify Porphyromonas gingivalis lipopolysaccharide (LPS) using a protocol of extraction, enzymatic digestión and high resolution chromatography. P. gingivalis bacteria was cultured in anaerobiosis, their membranes were extracted using the phenol-water method, then subjected to DNAse, RNAse and protease digestion and finally, the extract was separated by chromatography using Sephacryl S-200. The purified extract was characterized by silver staining after polyacrylamide gel electrophoresis and 2-keto-3-deoxioctanoic acid (KDO) was detected using the Purpald’s method. A preparation free of nucleic acid-, protein- or polysaccharides was obtained. The chromatographic separation showed high resolution since there was two discrete peaks with different components. The purification protocol allowed us to obtain a highly purified P. gingivalis LPS which could be used in future tests to evaluate its behavior in vitro and in vivo and elucidate its function, as well as to obtain LPS from other períodontopatic bacteria to address the association of períodontal disease with cardiovascular diseases

Inheritance of the Resistance to Acanthoscelides obtectus (Say.) in a Heterogeneous Inbred Families Population of Common Bean (Phaseolus vulgaris L.)

The bean weevil Acanthoscelides obtectus is one of the world’s main pests of stored beans. The heterogeneous inbred family (HIF) population of near-isogenic lines (NILs) could be an exceptional strategy to study the inheritance of the resistance against A. obtectus. We developed a HIF population of 148 NILs of R-bufa-80-12. The objectives of this research were as follows: (1) to study and understand the genetics of the attack resistance to A. obtectus in a HIF population and (2) to identify the best lines to provide weevil resistance. The pure lines of the HIF population showed a great variability for all the analyzed traits. The traits studied in this research have a normal distribution showing continuous variation, so they are considered to be quantitatively inherited. The heritabilities for resistance traits were low and very low, ranging from 0.09 to 0.17. The heritability for 100 seed weight was the highest, with a significant value of 0.90. The best lines of the HIF population for resistance to A. obtectus comprised Line-45, Line-129, Line-124, Line-142 and Line-47. In general, these lines presented lower preference of adults, and lower consumption in grams and in percentages. However, lines 45 and 129 are the most interesting from a commercial point of view because they combine resistance and seed weight

Identification of Resistance to the Corn Weevil (<i>Sitophilus zeamais</i> M.) in Mexican Maize Races (<i>Zea mays</i> L.)

Sitophilus zeamais (Motsch.) (Coleoptera: Curculionidae) has a global distribution and is one of the most important post-harvest pests of maize (Zea mays L.). Some Mexican maize races could be a novel source of resistance against S. zeamais to improve commercial maize, generating lines, varieties, and hybrids with resistance to the pest. These are original races from the center of origin of maize and have been exposed to selection pressure from S. zeamais and other pests for thousands of years, which probably resulted in some type of resistance. We studied the resistance of Mexican maize races to S. zeamais focusing on antixenosis, antibiosis, and tolerance. Antibiosis reduces the survival and reproduction of the insect or prolongs the time between generations, whereas antixenosis reduces the rate of initial and successive accumulation of the insect population. Obligate-antibiosis and free-choice bioassays were performed, and in those experiments, resistance traits and the consumption by S. zeamais were measured. The most resistant accession showed high adult mortality and fewer adults in the 1st generation, where the number of emerged adults is an ideal trait to evaluate the level of maize resistance to the pest. Net consumption (in grams) is the most economically important trait because it indicates the gross amount lost in a store, while yield losses (percentage of consumption) allow for studying tolerance. The type of endosperm did have an influence on the resistance/tolerance to S. zeamais. The flint varieties showed significantly higher mortality of adults before entering the seed, a lower quantity of emerged adults of the first generation in the obligate-antibiosis bioassay, and lower net consumption and percentage in both bioassays. In general, the varieties of the races Cristalino de Chihuahua, Apachito, and Azul showed high levels of resistance, with the Cristalino-079 (flint) and Azul (floury) accessions also being tolerant, and low levels of consumption by S. zeamais. Both could be used in breeding programs to reduce losses caused by S. zeamais

Worldwide Dissemination of <i>bla</i>_KPC Gene by Novel Mobilization Platforms in <i>Pseudomonas aeruginosa</i>: A Systematic Review

The dissemination of blaKPC-harboring Pseudomonas aeruginosa (KPC-Pa) is considered a serious public health problem. This study provides an overview of the epidemiology of these isolates to try to elucidate novel mobilization platforms that could contribute to their worldwide spread. A systematic review in PubMed and EMBASE was performed to find articles published up to June 2022. In addition, a search algorithm using NCBI databases was developed to identify sequences that contain possible mobilization platforms. After that, the sequences were filtered and pair-aligned to describe the blaKPC genetic environment. We found 691 KPC-Pa isolates belonging to 41 different sequence types and recovered from 14 countries. Although the blaKPC gene is still mobilized by the transposon Tn4401, the non-Tn4401 elements (NTEKPC) were the most frequent. Our analysis allowed us to identify 25 different NTEKPC, mainly belonging to the NTEKPC-I, and a new type (proposed as IVa) was also observed. This is the first systematic review that consolidates information about the behavior of the blaKPC acquisition in P. aeruginosa and the genetic platforms implied in its successful worldwide spread. Our results show high NTEKPC prevalence in P. aeruginosa and an accelerated dynamic of unrelated clones. All information collected in this review was used to build an interactive online map

Photodiodes based in La0.7Sr0.3MnO3/single layer MoS2 hybrid vertical heterostructures

The fabrication of artificial materials by stacking of individual two-dimensional (2D) materials is amongst one of the most promising research avenues in the field of 2D materials. Moreover, this strategy to fabricate new man-made materials can be further extended by fabricating hybrid stacks between 2D materials and other functional materials with different dimensionality making the potential number of combinations almost infinite. Among all these possible combinations, mixing 2D materials with transition metal oxides can result especially useful because of the large amount of interesting physical phenomena displayed separately by these two material families. We present a hybrid device based on the stacking of a single layer MoS onto a lanthanum strontium manganite (LaSrMnO) thin film, creating an atomically thin device. It shows a rectifying electrical transport with a ratio of 10, and a photovoltaic effect with V up to 0.4 V. The photodiode behaviour arises as a consequence of the different doping character of these two materials. This result paves the way towards combining the efforts of these two large materials science communities.Work at IMDEA was supported by MINECO (Ramón y Cajal 2014 program RYC-2014-01406, MAT2014-58399-JIN, FIS2015-67367-C2-1-P), the Comunidad de Madrid (MAD2D-CM Program (S2013/MIT-3007)) and NANOFRONTMAG-CM program (S2013/MIT-2850) and the European Commission under the Graphene Flagship (contract CNECTICT-604391) and FP7 ITN MOLESCO (project no. 606728). RF acknowledges support from the Netherlands Organisation for Scientific Research (NWO) through the research program Rubicon with project number 680-50-1515. YN acknowledges the grant from the China Scholarship Council (File NO. 201506120102). Work at UCM supported by Spanish MINECO through grants MAT2014-52405-C02-01 and by CAM through grant CAM S2013/MIT-2740. Work at ICMM is supported by Spanish MINECO through grant MAT2014-52405-C02-02