Chitosan application in maize (Zea mays) to counteract the effects of abiotic stress at seedling level

Worldwide, the conditions of biotic and abiotic stresses adversely affect the potential production of maize. Drought or heat facilitate the infection with fungi such as Aspergillus flavus and Fusarium moniliforme, and consequently increase the production of mycotoxins. There are several strategies for managing the problem, but in the future, people will prefer the cleaner and cheaper technology. The use of elicitors for protection of corn can be considered a cheap and clean technology. Chitosan elicitor is a linear polysaccharide produced commercially by deacetylation of chitin. It has been reported that this elicitor induce phytoalexin accumulation in plant tissue. Application of chitosan to seeds in rice significantly increased rice yield. About this, there are no reports in corn. For this reason, the aim of this study was to determine the protective effect of chitosan in maize seedlings subjected to abiotic stresses. To this end, three treatments were tested (a negative control, a positive control, and a group coated with chitosan solution) under four abiotic stresses conditions since their germination stage: drought, moisture, acid pH and alkaline pH. During five weeks, the seedlings growth was evaluated by measuring their total length, the length of leaves, stems and the thickness of these and presence of fungi. Positive effect was observed in seeds treated with chitosan or stressed with acidic pH in dimensions of seedlings and there was no fungal growth.Key words: Abiotic stress, Zea mays, chitosan, pH, drought, humidit

First histopathological study in kidneys of rodents naturally infected with Leptospira pathogenic species from Yucatan, Mexico

AbstractObjectiveTo report the renal histological lesions in synanthropic rodents, Mus musculus and Rattus rattus, naturally infected with Leptospira spp., captured in a rural community in Yucatan, Mexico.MethodsKidney samples of synanthropic rodents were collected from a rural community in Yucatan, Mexico. Polymerase chain reaction was used to detect Leptospira spp. infection. Tissue kidney was fixed in 10% buffered formalin, processed according to the usual techniques for paraffin inclusion, cut and stained with hematoxylin and eosin, and examined using a conventional electronic microscope.ResultsA total of 187 rodents were captured. Nine individuals (4.8%) were positive for Leptospira spp. in the molecular analysis. All renal lesions observed in the histopathological study had been reported previously for Leptospira spp. infection.ConclusionsThe histopathological lesions are present in the kidneys, plus the results of the polymerase chain reaction confirm that these rodents are true carriers of Leptospira spp

Visceral Obesity and Metabolic Syndrome Are Associated with Well-Differentiated Gastroenteropancreatic Neuroendocrine Tumors

The determinants for gastroenteropancreatic neuroendocrine tumors (GEP-NET) recent burden are matters of debate. Obesity and metabolic syndrome (MetS) are well established risks for several cancers even though no link with GEP-NETs was yet established. Our aim in this study was to investigate whether well-differentiated GEP-NETs were associated with obesity and MetS. Patients with well-differentiated GEP-NETs (n = 96) were cross-matched for age, gender, and district of residence with a control group (n = 96) derived from the general population in a case-control study. Patients presented gastro-intestinal (75.0%) or pancreatic (22.9%) tumors, grade G1 (66.7%) or G2 (27.1%) with localized disease (31.3%), regional metastasis (16.7%) or distant metastasis (43.8%) at diagnosis, and 45.8% had clinical hormonal syndromes. MetS was defined according to Joint Interim Statement (JIS) criteria. Well-differentiated GEP-NETs were associated with MetS criteria as well as the individual components' waist circumference, fasting triglycerides, and fasting plasma glucose (p = 0.003, p = 0.002, p = 0.011 and p < 0.001, respectively). The likelihood of the association was higher when the number of individual MetS components was greater than four. MetS and some individual MetS components including visceral obesity, dyslipidemia, and increased fasting glucose are associated with well-differentiated GEP-NET. This data provides a novel insight in unraveling the mechanisms leading to GEP-NET disease.This project was funded by a grant from Research Center of IPO-Porto (CI-IPOP 32-2015)info:eu-repo/semantics/publishedVersio

Exercise Capacity in Children and Adolescents With Congenital Heart Disease: A Systematic Review and Meta-Analysis

Congenital heart disease (CHD) entails structural defects in the morphogenesis of the heart or its main vessels. Analyzing exercise capacity of children and adolescents with CHD is important to improve their functional condition and quality of life, since it can allow timely intervention on poor prognostic factors associated with higher risk of morbidity and mortality.To describe exercise capacity in children and adolescents with CHD compared with healthy controls.A systematic review was carried out. Randomized clinical trials and observational studies were included assessing exercise capacity through direct and indirect methods in children and adolescents between 5 and 17 years-old. A sensitive analysis was performed including studies with CHD repaired participants. Additionally, it was sub-analyzed by age range (< and ? 12 years old). Two independent reviewers analyzed the studies, extracted the data, and assessed the quality of the evidence.5619 articles were found and 21 were considered for the review. Eighteen articles used the direct exercise capacity measurement method by cardiopulmonary exercise test (CPET). The CHD group showed significant differences in peak oxygen consumption (VO2peak) with a value of -7.9 ml/Kg/min (95% CI: -9.9, -5.9, p = 0.00001), maximum workload (Wmax) -41.5 (95% CI: -57.9, -25.1 watts, p = 0.00001), ventilatory equivalent (VE/VCO2 ) slope 2.6 (95% CI: 0.3, 4.8), oxygen pulse (O2 pulse)-2.4 ml/beat (95% CI: -3.7, -1.1, p = 0.0003), and maximum heart rate (HRmax) -15 bpm (95% CI: -18, -12 bpm, p = 0.00001), compared with healthy controls. Adolescents (? 12 yrs) with CHD had a greater reduction in VO2peak (-10.0 ml/Kg/min (95% CI: -12.0, -5.3), p < 0.00001), Wmax (-45.5 watts (95% CI: -54.4, -36.7), p < 0.00001) and HRmax (-21 bpm (95% CI: -28, -14), p<0.00001).Suffering CHD in childhood and adolescence is associated with lower exercise capacity as shown by worse VO2peak, Wmax, VE/VCO2 slope, O2 pulse, and HRmax compared with matched healthy controls. The reduction in exercise capacity was greater in adolescents.www.crd.york.ac.uk/prospero/display_record.php?RecordID=208963, identifier: CRD42020208963.Copyright © 2022 Villaseca-Rojas, Varela-Melo, Torres-Castro, Vasconcello-Castillo, Mazzucco, Vilaró and Blanco

Epidemic and Cascading Survivability of Complex Networks

Our society nowadays is governed by complex networks, examples being the power grids, telecommunication networks, biological networks, and social networks. It has become of paramount importance to understand and characterize the dynamic events (e.g. failures) that might happen in these complex networks. For this reason, in this paper, we propose two measures to evaluate the vulnerability of complex networks in two different dynamic multiple failure scenarios: epidemic-like and cascading failures. Firstly, we present \emph{epidemic survivability} ($ES$), a new network measure that describes the vulnerability of each node of a network under a specific epidemic intensity. Secondly, we propose \emph{cascading survivability} ($CS$), which characterizes how potentially injurious a node is according to a cascading failure scenario. Then, we show that by using the distribution of values obtained from $ES$ and $CS$ it is possible to describe the vulnerability of a given network. We consider a set of 17 different complex networks to illustrate the suitability of our proposals. Lastly, results reveal that distinct types of complex networks might react differently under the same multiple failure scenario

Análisis del comportamiento del magnetómetro kerr longitudinal para diferentes ángulos de incidencia

En este trabajo se realiza un análisis experimental de la relación entre el ángulo de incidencia y la intensidad de la señal Kerr, que influye en la forma del ciclo de histéresis, planteándose una relación directa entre ambos para la configuración longitudinal en el magnetómetro Kerr. Los resultados obtenidos evidencian un mejor comportamiento de dicha curva para el rango comprendido entre 10° y 60 ° del ángulo de incidencia

JNK isoforms control adult mammal hippocampal neurogenesis

[eng] In mammals, the term "Adult Neurogenesis” (AN) defines the process through which, throughout adulthood, new neurons are produced from neural stem cells (NSC). These NSC are located in a specific niche, concretely, in the subventricular zone (SVZ), lining the lateral ventricles, and in the subgranular zone (SGZ) in the dentate gyrus (DG) of the hippocampus. Controversially, new data have questioned the existence of this AN in the human brain seeing how only populations of immature neurons (IN), broadly dispersed within SGZ, have been detected. Either way, neurogenic activity in the hippocampus has been correlated with learning, memory formation and behavioral responses to stress, just like with the pathophysiology of many brain diseases and mood disorders. Various extracellular and intracellular stimuli have been shown to modulate survival, proliferation, and differentiation of adult-born cells in the hippocampus, especially through conserved stimuli-response mechanisms like the JNKs. In the present review, the JNK pathway and their control of adult hippocampal neurogenesis are described, evidencing the critical role of isoform JNK1.[cat] En mamíferos, el término “Neurogenesis Adulta (NA)”, se define como el proceso a través del cual, en adultos, se producen nuevas neuronas granulares a partir de células madre neurales (CMN). Estas CMN estan ubicadas en microambientes específicos, en concreto en la zona subventicular (ZSV), recubriendo los ventriculos laterales, y en la zona subgranular (ZSG) del giro dentado del hipocampo (GD). Sin embargo, nuevas informaciones han cuestionado la existencia de este proceso de neurogenesis adulta en el cerebro humano, ya que solamente se han detectado poblaciones de neuronas inmaduras (NI) dispersas a lo largo de la ZSG. Independientemente, la existencia de una actividad neurogénica en el hipocampo adulto se ha correlacionado con el aprendizaje, la formación de memoria y en el comportamiento ante situaciones de estrés, así como en la patofisiologia de diferentes patologías del cerebro, incluso en casos de alteraciones del estado de ánimo. Se ha demostrado que diferentes estímulos extracelulares e intracelulares controlan la supervivencia, la proliferación y la diferenciación de las nuevas neuronas del hipocampo, especialmente a través de mecanismos conservados de respuesta a estímulos como las JNKs. En la presente revisión se describe las JNK y su control de la neurogénesis hipocampal adulta, evidenciando el papel crucial de la isoforma JNK1

Análisis del comportamiento del magnetómetro kerr longitudinal para diferentes ángulos de incidencia

En este trabajo se realiza un análisis experimental de la relación entre el ángulo de incidencia y la intensidad de la señal Kerr, que influye en la forma del ciclo de histéresis, planteándose una relación directa entre ambos para la configuración longitudinal en el magnetómetro Kerr. Los resultados obtenidos evidencian un mejor comportamiento de dicha curva para el rango comprendido entre 10° y 60 ° del ángulo de incidencia

Análisis del comportamiento del magnetómetro kerr longitudinal para diferentes ángulos de incidencia

En este trabajo se realiza un análisis experimental de la relación entre el ángulo de incidencia y la intensidad de la señal Kerr, que influye en la forma del ciclo de histéresis, planteándose una relación directa entre ambos para la configuración longitudinal en el magnetómetro Kerr. Los resultados obtenidos evidencian un mejor comportamiento de dicha curva para el rango comprendido entre 10° y 60 ° del ángulo de incidencia