Temperature effect on oxidative stress and egg quality-related genes on post-ovulatory eggs and ovary of red cusk-eel (Genypterus chilensis)

Red cusk-eel (Genypterus chilensis) is a native species with potential for Chilean aquaculture diversification. However, no information exists on the effects of temperature on oxidative stress and eggs quality markers in post-ovulatory eggs and ovary of this species. We determine that high and low temperature generate oxidative damage on post-ovulatory eggs, with no effect on ovary. Temperature induces thermal stress markers expression on post-ovulatory eggs, and modulates antioxidant and eggs quality markers on post-ovulatory eggs and ovary, information to consider for quality evaluation in the red cusk-eel management.     

Abiotic factors driving cyanobacterial biomass and composition under perennial bloom conditions in tropical latitudes

Hydrobiologia - While warming and eutrophication have increased the frequency and magnitude of harmful cyanobacterial blooms globally, the scenario for many eutrophic tropical freshwaters is a...     

Spatial cognitive abilities of a tide-pool fish show resilience to noise pollution

Journal of Ethology - Noise pollution may impair the cognitive performances of several animal species, producing suboptimal behavioral responses. Involuntary shifts in attention from noise...     

Plant plasma membrane‐resident receptors: Surveillance for infections and coordination for growth and development

As sessile organisms, plants are exposed to pathogen invasions and environmental fluctuations. To overcome the challenges of their surroundings, plants acquire the potential to sense endogenous and exogenous cues, resulting in their adaptability. Hence, plants have evolved a large collection of plasma membrane-resident receptors, including RECEPTOR-LIKE KINASEs(RLKs) and RECEPTOR-LIKE PROTEINs(RLPs) to perceive those signals and regulate plant growth,development, and immunity. The ability of RLKs and RLPs to recognize distinct ligands relies on diverse categories of extracellular domains evolved. Co-regulatory receptors are often required to associate with RLKs and RLPs to facilitate cellular signal transduction. RECEPTOR-LIKE CYTOPLASMIC KINASEs(RLCKs) also associate with the complex, bifurcating the signal to key signaling hubs, such as MITOGEN-ACTIVATED PROTEIN KINASE(MAPK) cascades, to regulate diverse biological processes. Here, we discuss recent knowledge advances in understanding the roles of RLKs and RLPs in plant growth, development, and immunity, and their connection with co-regulatory receptors, leading to activation of diverse intracellular signaling pathways.     

Potent Anti-Candida Fraction Isolated from Capsicum chinense Fruits Contains an Antimicrobial Peptide That is Similar to Plant Defensin and is Able to Inhibit the Activity of Different α-Amylase Enzymes

Antimicrobial peptides (AMPs) are molecules present in several life forms, possess broad-spectrum of inhibitory activity against pathogenic microorganisms, and are a promising alternative to combat the multidrug resistant pathogens. The aim of this work was to identify and characterize AMPs from Capsicum chinense fruits and to evaluate their inhibitory activities against yeasts of the genus Candida and α-amylases. Initially, after protein extraction from fruits, the extract was submitted to anion exchange chromatography resulting two fractions. Fraction D1 was further fractionated by molecular exclusion chromatography, and three fractions were obtained. These fractions showed low molecular mass peptides, and in fraction F3, only two protein bands of approximately 6.5 kDa were observed. Through mass spectrometry, we identified that the lowest molecular mass protein band of fraction F3 showed similarity with AMPs from plant defensin family. We named this peptide CcDef3 (Capsicum chinense defensin 3). The antifungal activity of these fractions was analyzed against yeasts of the genus Candida. At 200 μg/mL, fraction F1 inhibited the growth of C. tropicalis by 26%, fraction F2 inhibited 35% of the growth of C. buinensis, and fraction F3 inhibited all tested yeasts, exhibiting greater inhibition activity on the growth of the yeast C. albicans (86%) followed by C. buinensis (69%) and C. tropicalis (21%). Fractions F1 and F2 promoted membrane permeabilization of all tested yeasts and increased the endogenous induction of reactive oxygen species (ROS) in C. buinensis and C. tropicalis, respectively. We also observed that fraction F3 at a concentration of 50 µg/mL inhibited the α-amylase activities of Tenebrio molitor larvae by 96% and human salivary by 100%. Thus, our results show that fraction F3, which contains CcDef3, is a very promising protein fraction because it has antifungal potential and is able to inhibit the activity of different α-amylase enzymes.

     

Increased hip internal abduction moment and reduced speed are the gait strategies used by women with knee osteoarthritis

The purpose of this study was to identify the gait strategies in women with mild and moderate knee osteoarthritis (OA). Forty women diagnosed with OA of the knee and 40 healthy women participated in the study. Toe-out progression angle, trunk lateral lean, hip internal abduction moment and gait speed were measured using Qualisys ProReflex System and two force plates. Principal component analysis was applied to extract features from the gait waveforms data that characterized the waveforms main modes of temporal variation. Discriminant analysis with a stepwise model was conducted to determine which strategies could best discriminate groups. According to the discriminant model, the PC2 of the internal abduction moment of the hip and the gait speed were the most discriminatory variables between the groups. The OA group showed decreased gait speed, decreased hip internal abduction moment during the loading response phase, and increased hip internal abduction moment during the mid and terminal stance phases. Interventions that may increase hip internal abduction moment, such as the strengthening of the hip abductors muscles, may benefit women with knee OA. Training slower than normal gait speeds must be considered in light of potential adverse implications on overall physical function, daily tasks, and safety.