Ensuring successful introduction of Wolbachia in natural populations of Aedes aegypti by means of feedback control

The control of the spread of dengue fever by introduction of the intracellular parasitic bacterium Wolbachia in populations of the vector Aedes aegypti, is presently one of the most promising tools for eliminating dengue, in the absence of an efficient vaccine. The success of this operation requires locally careful planning to determine the adequate number of individuals carrying the Wolbachia parasite that need to be introduced into the natural population. The introduced mosquitoes are expected to eventually replace the Wolbachia-free population and guarantee permanent protection against the transmission of dengue to human. In this study, we propose and analyze a model describing the fundamental aspects of the competition between mosquitoes carrying Wolbachia and mosquitoes free of the parasite. We then use feedback control techniques to devise an introduction protocol which is proved to guarantee that the population converges to a stable equilibrium where the totality of mosquitoes carry Wolbachia.Comment: 24 pages, 5 figure

Diarrea vírica bovina: etiología, formas clínicas, distribución del virus y patogenia

El virus de la diarrea vírica bovina (vDVB) es un agente de distribución mundial y responsable de cuantiosas pérdidas económica a la cabaña bovina, estando clasificado dentro de la familia Flaviviridae junto a otros pestivirus como el virus de la peste porcina clásica, el virus de la enfermedad de la frontera de la oveja y el virus de la hepatitis C. Este virus se caracteriza por causar una amplia variedad de formas clínicas que van desde forma subagudas, que pasan desapercibidas, a formas caracterizadas por desarrollar una intensa leucopenia, trombocitopenia y hemorragias. Acorde con sus diferencias antigénicas y genéticas, los aislados del virus se pueden clasificar en 2 genotipos o especies: vDVB tipo 1 y vDVB tipo 2. El primero causa enfermedad leve pero en vacas preñadas, las infecciones fetales pueden inducir abortos y otras patologías reproductivas. El vDVB tipo 2 está asociado principalmente a la enfermedad respiratoria severa y a un cuadro hemorrágico agudo, caracterizado por trombocitopenia, diarrea hemorrágica, epistaxis, petequias, equimosis en mucosas, anemia, sangrado en zonas de inyección, pirexia, leucopenia y muerte.Independientemente del genotipo al que pertenezca, el vDVB puede ser clasificado en 2 biotipos acorde con su efecto sobre cultivos celulares: citopático (CP) y no citopático (NCP), siendo estos últimos los más comunes en la naturaleza. La infección del feto con cepas NCP entre los días 40 y 120 de la gestación, puede dar lugar al nacimiento de animales persistentemente infectados (PI). En estos animales el virus se distribuye ampliamente a través de todos los órganos, siendo el daño limitado, lo que permite que la gestación continúe. Estos animales están predispuestos a padecer infecciones secundarias, así como a desarrollar la denominada enfermedad de las mucosas cuando se infectan con cepas CP antigénicamente homólogas

Contact dynamics in a gently vibrated granular pile

We use multi-speckle diffusive wave spectroscopy (MSDWS) to probe the micron-scale dynamics of a granular pile submitted to discrete gentle taps. The typical time-scale between plastic events is found to increase dramatically with the number of applied taps. Furthermore, this microscopic dynamics weakly depends on the solid fraction of the sample. This process is strongly analogous to the aging phenomenon observed in thermal glassy systems. We propose a heuristic model where this slowing down mechanism is associated with a slow evolution of the distribution of the contact forces between particles. This model accounts for the main features of the observed dynamics.Comment: 4 pages, 4 figure

Whole transcriptome analysis of the hippocampus: toward a molecular portrait of epileptogenesis

<p>Abstract</p> <p>Background</p> <p>Uncovering the molecular mechanisms involved in epileptogenesis is critical to better understand the physiopathology of epilepsies and to help develop new therapeutic strategies for this prevalent and severe neurological condition that affects millions of people worldwide.</p> <p>Results</p> <p>Changes in the transcriptome of hippocampal cells from rats subjected to the pilocarpine model of epilepsy were evaluated by microarrays covering 34,000 transcripts representing all annotated rat genes to date. Using such genome-wide approach, differential expression of nearly 1,400 genes was detected during the course of epileptogenesis, from the early events post <it>status epilepticus (SE) </it>to the onset of recurrent spontaneous seizures. Most of these genes are novel and displayed an up-regulation after <it>SE</it>. Noteworthy, a group of 128 genes was found consistently hyper-expressed throughout epileptogenesis, indicating stable modulation of the p38MAPK, Jak-STAT, PI3K, and mTOR signaling pathways. In particular, up-regulation of genes from the TGF-beta and IGF-1 signaling pathways, with opposite effects on neurogenesis, correlate with the physiopathological changes reported in humans.</p> <p>Conclusions</p> <p>A consistent regulation of genes functioning in intracellular signal transduction regulating neurogenesis have been identified during epileptogenesis, some of which with parallel expression patterns reported in patients with epilepsy, strengthening the link between these processes and development of epilepsy. These findings reveal dynamic molecular changes occurring in the hippocampus that may serve as a starting point for designing alternative therapeutic strategies to prevent the development of epilepsy after acquired brain insults.</p

Role of SOCS3 in POMC Neurons in metabolic and cardiovascular regulation.

Suppressor of cytokine signaling 3 (SOCS3) is a negative regulator of leptin signaling. We previously showed that the chronic effects of leptin on blood pressure (BP) and glucose regulation are mediated by stimulation of pro-opiomelanocortin (POMC) neurons. In this study, we examined the importance of endogenous SOCS3 in POMC neurons in control of metabolic and cardiovascular function and potential sex differences. Male and female SOCS3flox/flox/POMC-Cre mice in which SOCS3 was selectively deleted in POMC neurons and control SOCS3flox/flox mice were studied during a control diet (CD) or high fat diet (HFD) and during chronic leptin infusion. On CD, male and female SOCS3flox/flox/POMC-Cre mice were lighter in body weight despite similar food intake compared to control mice. Male SOCS3flox/flox/POMC-Cre mice exhibited increased energy expenditure. BP and heart rate were similar in male and female SOCS3flox/flox/POMC-Cre and control mice on CD. On a HFD, male and female SOCS3flox/flox/POMC-Cre mice showed attenuated weight gain. Female SOCS3flox/flox/POMC-Cre mice exhibited greater HFD-induced elevations in baseline BP and BP responses to air jet stress test compared to control mice. Chronic leptin infusion produced similar responses in all groups for food intake, body weight, oxygen consumption, blood glucose, BP and heart rate. Thus, SOCS3 deficiency in POMC neurons influences body weight regulation in CD and HFD and differentially affects BP and energy balance in a sex specific manner, but does not amplify the dietary, glycemic or cardiovascular effects of leptin

Targeting immunometabolism during cardiorenal injury: roles of conventional and alternative macrophage metabolic fuels

Macrophages play critical roles in mediating and resolving tissue injury as well as tissue remodeling during cardiorenal disease. Altered immunometabolism, particularly macrophage metabolism, is a critical underlying mechanism of immune dysfunction and inflammation, particularly in individuals with underlying metabolic abnormalities. In this review, we discuss the critical roles of macrophages in cardiac and renal injury and disease. We also highlight the roles of macrophage metabolism and discuss metabolic abnormalities, such as obesity and diabetes, which may impair normal macrophage metabolism and thus predispose individuals to cardiorenal inflammation and injury. As the roles of macrophage glucose and fatty acid metabolism have been extensively discussed elsewhere, we focus on the roles of alternative fuels, such as lactate and ketones, which play underappreciated roles during cardiac and renal injury and heavily influence macrophage phenotypes

Using of essential oils in the treatment of mice infected with Trypanosoma evansi

Objective. This study aimed to test the effectiveness of copaiba, andiroba and aroeira essential oils for controlling trypanosomosis by Trypanosoma evansi with mice as experimental model. Materials and methods. Sixty-six mice were divided into eleven groups (A to L) with six animals each. Group A was the unique composed by healthy and uninfected animals (negative control). Animals in groups B to L were inoculated with 0.1 mL of blood containing 2.7 x 106 trypanosomes. Group B was used as a positive control without treatment. In experiment were tested copaiba (C, D and E), andiroba (F, G and H) and aroeira (I, J and L) oils at doses of 0.6, 0.8 and 1.0 mL kg-1 to infected mice (T. evansi). Results. These protocols did not provide curative efficacy; however, the mice treated with highest dose of copaiba showed a significant increase in the longevity when compared others groups. Conclusions. Previously in our studies, these essential oils have shown trypanocidal activity in vitro, but when they were tested in vivo in mice infected with T. evansi, this trypanocidal activity, or the curative effect was not found, being only able to prolong the lifespan of the animals treated with copaiba oil

Efeito da pré-embebição das sementes e do substrato na germinação e no desenvolvimento inicial do maracujazeiro-doce.

O objetivo deste trabalho foi avaliar o efeito da pré-embebição das sementes em água e do tipo de substrato na germinação e no desenvolvimento inicial do maracujazeiro-doce (P. alata Curtis). O trabalho foi realizado no Departamento de Fitotecnia, da Universidade Federal de Viçosa (MG). As sementes foram extraídas de frutos maduros, e somente uma porção foi embebida em água destilada, durante 24 horas. Posteriormente, no interior da casa de vegetação, as sementes foram semeadas em caixas plásticas, utilizando-se quatro substratos (areia; Plantmax?; torta de filtro e a mistura Plantmax + areia + torta de filtro (1:1:1 v/v). Foi utilizado o delineamento experimental em blocos casualizados, num fatorial 2 x 4 (pré-embebição x substrato), com quatro repetições, considerando como unidade experimental cada 50 sementes. Aos 33 dias após a semeadura, foram analisados: porcentagem de germinação e de sobrevivência das plântulas; número de folhas; comprimento total e comprimento de raiz das plântulas; índice de velocidade de emergência; e massa da matéria seca total das plântulas. Concluiu-se que a embebição das sementes em água não interferiu na germinação do maracujazeiro-doce. Em geral, obtiveram-se os maiores resultados nas variáveis analisadas quando se utilizou o substrato comercial Plantmax, sendo seu uso recomendado para formação de plântulas de maracujazeiro-doce

In search for potential antidiabetic compounds from natural sources: docking, synthesis and biological screening of small molecules from Lycium spp. (Goji)

© 2019 Current clinical antidiabetic drugs, like rosiglitazone 1, have been implicated in some serious side effects like edema, weight gain, and heart failure, making it necessary to find alternative agents. Partial agonists of peroxisome-proliferator activated receptor-gamma (PPARγ) were determined to possess improved insulin sensitivity without undeseirable side-effects when compared to full agonists of PPARγ, like rosiglitazone 1. The traditional Chinese medicine (TCM) plants, Goji (Lycium barbarum and Lycium chinense) are widely used for treating symptoms related to various diseases including diabetes and hypertension. Twenty-seven reported compounds from Goji were docked into both partial- and full-agonist binding sites of PPARγ. Amongst the docked compounds, phenylethylamide-based phytochemicals (5–9) (termed as tyramine-derivatives, TDs) were found to possess good docking scores and binding poses with favorable interactions. Synthesis of 24 TDs, including three naturally occuring amides (6, 8, 9) were synthesized and tested for PPARγ gene induction with cell-based assay. Three compounds showed similar or higher fold induction than the positive control, rosiglitazone. Among these three active TDs, trans-N-feruloyloctopamine (9) and tyramine derivatives-enriched extract (TEE) (21%) of the root bark of L. chinense were further studied in vivo using db/db mice. However, both TEE as well as 9 did not show significant antidiabetic properties in db/db mice. In vivo results suggest that the proposed antidiabetic property of Lycium species may not be due to tyramine derivatives alone. Further studies of tyramine derivatives or enriched extract(s) for other bioactivities like hypocholesterolemic activities, and studies of novel isolated compounds from Goji will enable a more complete understanding of their bioactivities