Hormetic and transcriptomic responses of the toxic alga Prymnesium parvum to glyphosate.

Growth of the toxic alga Prymnesium parvum is hormetically stimulated with environmentally relevant concentrations of glyphosate. The mechanisms of glyphosate hormesis in this species, however, are unknown. We evaluated the transcriptomic response of P.

Spatial control of sensory adaptation modulates mechanosensing in .

Sensory signaling pathways use adaptation to dynamically respond to changes in their environment. Here, we report the mechanism of sensory adaptation in the Pil-Chp mechanosensory system, which the important human pathogen uses to sense mechanical stimuli during surface exploration. Using biochemistry, genetics, and cell biology, we discovered that the enzymes responsible for adaptation, a methyltransferase and a methylesterase, are segregated to opposing cell poles as explore surfaces.

Two antagonistic response regulators control Pseudomonas aeruginosa polarization during mechanotaxis.

The opportunistic pathogen Pseudomonas aeruginosa adapts to solid surfaces to enhance virulence and infect its host. Type IV pili (T4P), long and thin filaments that power surface-specific twitching motility, allow single cells to sense surfaces and control their direction of movement. T4P distribution is polarized to the sensing pole by the chemotaxis-like Chp system via a local positive feedback loop.

A retrospective study of clinical and epidemiological characteristics of snakebite in Napo Province, Ecuadorian Amazon.

Background: Snakebite envenoming remains a relevant public health problem in tropical and subtropical countries. In Ecuador, this is particularly true in an area of great diversity like the Amazon region. Nevertheless, there is scarce information about epidemiological and clinical characteristics of these accidents in this area.

Group Emotion Detection Based on Social Robot Perception.

Social robotics is an emerging area that is becoming present in social spaces, by introducing autonomous social robots. Social robots offer services, perform tasks, and interact with people in such social environments, demanding more efficient and complex Human-Robot Interaction (HRI) designs. A strategy to improve HRI is to provide robots with the capacity of detecting the emotions of the people around them to plan a trajectory, modify their behaviour, and generate an appropriate interaction with people based on the analysed information.

Air, land, and water variables associated with the first appearance and current spatial distribution of toxic Prymnesium parvum blooms in reservoirs of the Southern Great Plains, USA.

This study examined the association of air, land, and water variables with the first historical occurrence and current distribution of toxic Prymnesium parvum blooms in reservoirs of the Brazos River and Colorado River, Texas (USA). One impacted and one reference reservoir were selected per basin. Land cover and use variables were estimated for the whole watershed (WW) and a 0.

Mechanotaxis directs twitching motility.

The opportunistic pathogen explores surfaces using twitching motility powered by retractile extracellular filaments called type IV pili (T4P). Single cells twitch by sequential T4P extension, attachment, and retraction. How single cells coordinate T4P to efficiently navigate surfaces remains unclear.

Growth of the harmful alga, Prymnesium parvum (Prymnesiophyceae), after gradual and abrupt increases in salinity.

Prymnesium parvum is a euryhaline, toxin-producing microalga. Although its abundance in inland waters and growth potential in the laboratory is reduced at high salinity (>20), the ability of inland strains to adjust their growth after long-term residence in high salinity is uncertain. An inland strain of P.

Bothrops atrox from Ecuadorian Amazon: Initial analyses of venoms from individuals.

Bothrops atrox is the most clinically relevant snake species within the Amazon region, which includes Ecuadorian territories. It comprises a large distribution, which could contribute to the genetic and venomic variation identified in the species. The high variability and protein isoform diversity of its venom are of medical interest, since it can influence the clinical manifestations caused by envenomation and its treatment.

Fatal brain hemorrhage after Bothrops asper bite in the Catatumbo region of Colombia.

Snake bites are a public health problem in tropical and subtropical regions of the world. They occur especially in rural workers and are an important source of disability and mortality. We present the case of a 59-year-old farmer from the Catatumbo region of Colombia who was bitten by a B.

Movement of synthetic organic compounds in the food web after the introduction of invasive quagga mussels (Dreissena bugensis) in Lake Mead, Nevada and Arizona, USA.

Introductions of dreissenid mussels in North America have been a significant concern over the last few decades. This study assessed the distribution of synthetic organic compounds (SOCs) in the food web of Lake Mead, Nevada/Arizona, USA and how this distribution was influenced by the introduction of invasive quagga mussels. A clear spatial gradient of SOC concentrations in water was observed between lake basins downstream of populated areas and more rural areas.

Assessing the stability of historical and desiccated snake venoms from a medically important Ecuadorian collection.

Bothrops asper and Bothrops atrox are important venomous snakes from Ecuador responsible for the most of ophidic accidents, which in the past were treated with a national polyvant antivenom. For years, the venom pools were collected and stored at room temperature in a laboratory. Taking into account the controversial ability of desiccated samples to retain their biological effects and enzymatic activities, we investigated the biochemical and toxicological properties of venoms after years of storage.

Off-line and on-line optical monitoring of microalgal growth.

The growth of microalgae cultures was successfully monitored, using classic off-line optical techniques (optical density and fluorescence) and on-line analysis of digital images. In this study, we found that the chlorophyll fluorescence ratio / has a linear correlation with the logarithmic concentration of microalgae. By using digital images, the biomass concentration correlated with the luminosity of the images through an exponential equation and the length of penetration of a super luminescent blue beam (λ = 440 nm) through an inversely proportional function.

Growth response of the ichthyotoxic haptophyte, Prymnesium parvum Carter, to changes in sulfate and fluoride concentrations.

Golden alga Prymnesium parvum Carter is a euryhaline, ichthyotoxic haptophyte (Chromista). Because of its presumed coastal/marine origin where SO42- levels are high, the relatively high SO42- concentration of its brackish inland habitats, and the sensitivity of marine chromists to sulfur deficiency, this study examined whether golden alga growth is sensitive to SO42- concentration. Fluoride is a ubiquitous ion that has been reported at higher levels in golden alga habitat; thus, the influence of F- on growth also was examined.

Environmental regulation of sex determination in fishes: Insights from Atheriniformes.

Sex determination is the first step toward the establishment of phenotypic sex in most vertebrates. Aquatic poikilotherms such as teleost fishes exhibit a high diversity of sex-determination mechanisms and gonadal phenotypes that are remarkably plastic and responsive to a variety of environmental factors (e.g.

Enabling genetic analysis of diverse bacteria with Mobile-CRISPRi.

The vast majority of bacteria, including human pathogens and microbiome species, lack genetic tools needed to systematically associate genes with phenotypes. This is the major impediment to understanding the fundamental contributions of genes and gene networks to bacterial physiology and human health. Clustered regularly interspaced short palindromic repeats interference (CRISPRi), a versatile method of blocking gene expression using a catalytically inactive Cas9 protein (dCas9) and programmable single guide RNAs, has emerged as a powerful genetic tool to dissect the functions of essential and non-essential genes in species ranging from bacteria to humans.

Low-dose stimulation of growth of the harmful alga, Prymnesium parvum, by glyphosate and glyphosate-based herbicides.

Glyphosate-based herbicides (GBH) are widely used around the globe. While generally toxic to phototrophs, organic phosphorus in glyphosate can become available to glyphosate-resistant phytoplankton and contribute to algal bloom development. Few studies have examined the effects of GBH on growth of eukaryotic microalgae and information for the toxic bloom-forming haptophyte, Prymnesium parvum, is limited.

Harnessing snake venom phospholipases A to novel approaches for overcoming antibiotic resistance.

The emergence of antibiotic resistance drives an essential race against time to reveal new molecular structures capable of addressing this alarming global health problem. Snake venoms are natural catalogs of multifunctional toxins and privileged frameworks, which serve as potential templates for the inspiration of novel treatment strategies for combating antibiotic resistant bacteria. Phospholipases A (PLA s) are one of the main classes of antibacterial biomolecules, with recognized therapeutic value, found in these valuable secretions.

Growth-suppressing and algicidal properties of an extract from Arundo donax, an invasive riparian plant, against Prymnesium parvum, an invasive harmful alga.

This study examined the ability of acidic and neutral/alkaline fractions of a methanolic extract from giant reed (Arundo donax) and of two of its constituents, gramine and skatole, to inhibit growth of the ichthyotoxic golden alga (Prymnesium parvum) in batch culture. For this study, growth suppression was defined as inhibition of maximum cell density, algicidal activity as early occurrence of negative growth, and algistatic activity as lack of net growth. The acidic fraction did not affect algal growth.

[Norbert Elias on the phenomenology of aging and death].

This study focuses on the contribution by German sociologist Norbert Elias (1897-1990) to the theme of aging and death. A reading of Elias' work allows reconsidering his analyses and perspectives on the thresholds of aging and death in societies with different demographic histories. Norbert Elias addressed these issues in The Loneliness of the Dying, published in 1982 in Germany and with an expanded version in 1985 in England.