Environmental persistence of 2,3,7,8-tetrachlorodibenzo-<Emphasis Type="Italic">p</Emphasis>-dioxin in soil around hardstand 7 at eglin air force base,Florida

Background and Goal  A number of global events have generated intense scientific scrutiny and public concern of polychlorinated dibenzo-p-dioxins (dioxin). DIoxins have been associated with a range of adverse health effects. 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is recognized as among the most dangerous of the dioxin compounds, and was a contaminant found In one of the herbicides used for vegetation control during the Vietnam conflict: Agent Orange. As a result of purging spray systems and leaking drums of Agent Orange concentrate, TCDD contamination occurred in the soils surrounding Hardstand 7 at Eglin Air Force Base, Florida. This research uses a multimedia model to estimate the TCDD concentrations in surface soil around Hardstand 7 for a 70-year time Interval beginning with observed surface soil concentrations 1984. Methods  Hardstand 7 is a nearly 40-m circular concrete and asphalt aircraft parking area. The hardstand was used as a staging area for spraying equipment used to disseminate herbicide In a test area called C-52A within EAFB. Concentrated herbicide was also stored in 208-L barrels for use with the equipment, and later, for disposal. In 1984, a field investigation characterized the extent of TCDD contamination in surface soils around Hardstand 7 using a radial sampling protocol. The 1984 observed concentrations and locations was used in a multimedia model, CalTOX, as an initial source term concentrations and locations to estimate expected concentrations during the subsequent 70-years. Results  The results indicate that more than 94% of the TCDD observed in surface soils 1984 will remain after a 70-year period. Access restrictions and remediation activities at the site eliminate bar verification of the CalTOX estimates. Conclusions. TCDD is highly persistent in the soil medium and natural attenuation may not produce a significant decrease In soil concentrations. Recommendation  Active remediation actions may be required to prevent exposure to TCDD contamination surface soils. Verifying CalTOX concentration estimates an Important step that should be performed, however, the, model provides an easy to use tool to estimate TCDD surface soil contamination at herbicide storage or dispersion staging sites.     

Shedding light on the migratory patterns of the Amazonian goliath catfish,Brachyplatystoma platynemum,using otolith 87Sr/86Sr analyses

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Responsible Research and Innovation Framework,the Nagoya Protocol and Other European Blue Biotechnology Strategies and Regulations: Gaps Analysis and Recommendations for Increased Knowledge in the Marine Biotechnology Community

As the quest for marine-derived compounds with pharmacological and biotechnological potential upsurges, the importance of following regulations and applying Responsible Research and Innovation (RRI) also increases. This article aims at: (1) presenting an overview of regulations and policies at the international and EU level, while demonstrating a variability in their implementation; (2) highlighting the importance of RRI in biodiscovery; and (3) identifying gaps and providing recommendations on how to improve the market acceptability and compliance of novel Blue Biotechnology compounds. This article is the result of the work of the Working Group 4 “Legal aspects, IPR and Ethics” of the COST Action CA18238 Ocean4Biotech, a network of more than 130 Marine Biotechnology scientists and practitioners from 37 countries. Three qualitative surveys (“Understanding of the Responsible Research and Innovation concept”, “Application of the Nagoya Protocol in Your Research”, and “Brief Survey about the experiences regarding the Nagoya Protocol”) indicate awareness and application gaps of RRI, the Nagoya Protocol, and the current status of EU policies relating to Blue Biotechnology. The article categorises the identified gaps into five main categories (awareness, understanding, education, implementation, and enforcement of the Nagoya Protocol) and provides recommendations for mitigating them at the European, national, and organisational level.     

Cytoprotection by neutral fraction of tannat red wine against oxidative stress-induced cell death

Some of the beneficial effects of the Mediterranean diet on human pathologies have been attributed to red wine polyphenols. It has been postulated that the antioxidant activity of the latter would be also responsible for the cytoprotective capacity of red wine that has been reported in a few papers. Nevertheless, red wine shows a complex composition, and the active fraction is not known yet. In this context, the protective capacity of total lyophilized extracts of red wine and anthocyanin, neutral, or acidic fractions, was explored in PC12 cells in culture after a hydrogen peroxide insult. Although all fractions showed high antioxidant activity, only the neutral fraction was cytoprotective. The analysis of this active fraction showed that it was rich in the aglycons quercetin and myricetin as well as the glycosides of kaempferol, isorhamnetin, epicatechin, and catechin, some of which are known to be cytoprotective. This is the first paper to reveal the active fraction of total wine responsible of its cytoprotection.     

Specific mutations induced by triplex-forming oligonucleotides in mice

Triplex-forming oligonucleotides (TFOs) recognize and bind to specific duplex DNA sequences and have been used extensively to modify gene function in cells. Although germ line mutations can be incorporated by means of embryonic stem cell technology, little progress has been made toward introducing mutations in somatic cells of living organisms. Here we demonstrate that TFOs can induce mutations at specific genomic sites in somatic cells of adult mice. Mutation detection was facilitated by the use of transgenic mice bearing chromosomal copies of the supF and cII reporter genes. Mice treated with a supF-targeted TFO displayed about fivefold greater mutation frequencies in the supF gene compared with mice treated with a scrambled sequence control oligomer. No mutagenesis was detected in the control gene (cII) with either oligonucleotide. These results demonstrate that site-specific, TFO-directed genome modification can be accomplished in intact animals.     

Phosphorylation of ULK1 (hATG1) by AMP-activated protein kinase connects energy sensing to mitophagy

Adenosine monophosphate-activated protein kinase (AMPK) is a conserved sensor of intracellular energy activated in response to low nutrient availability and environmental stress. In a screen for conserved substrates of AMPK, we identified ULK1 and ULK2, mammalian orthologs of the yeast protein kinase Atg1, which is required for autophagy. Genetic analysis of AMPK or ULK1 in mammalian liver and Caenorhabditis elegans revealed a requirement for these kinases in autophagy. In mammals, loss of AMPK or ULK1 resulted in aberrant accumulation of the autophagy adaptor p62 and defective mitophagy. Reconstitution of ULK1-deficient cells with a mutant ULK1 that cannot be phosphorylated by AMPK revealed that such phosphorylation is required for mitochondrial homeostasis and cell survival during starvation. These findings uncover a conserved biochemical mechanism coupling nutrient status with autophagy and cell survival.     

Aerobic versus Anaerobic Microbial Degradation of Etofenprox in a California rice field soil

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Bovine genital campylobacteriosis (vibriosis): vaccination of experimentally infected bulls

The therapeutic efficacy of a Campylobacter fetus subsp venerealis bacterin was determined in experimentally infected bulls. Ten of twelve 5-year-old Angus bulls became infected after being infused intrapreputially with C fetus subsp venerealis. Of the 10 bulls, 6 were vaccinated with 5 ml of C fetus subsp venerealis vaccine on 2 occasions 4 weeks apart. Preputial washings of the vaccinated bulls were culturally negative by the 8th week after primary vaccination. None of the 18 heifers exposed to the vaccinated bulls became infected. The 4 infected, nonvaccinated bulls remained culturally positive to C fetus (P less than 0.002), and each bull infected at least 1 heifer (P less than 0.001). Two noninfected, nonvaccinated bulls remained culturally negative and did not infect any heifer. The 4 infected, nonvaccinated bulls were then vaccinated. Two bulls remained infected 9 weeks after primary vaccination, as determined by the virgin heifer test and cultural examination of preputial washings. Serologic data from 7 sampling periods were different (P less than 0.001) for vaccinated vs nonvaccinated bulls at 4 (against K antigen) or 6 (against O antigen) weeks after primary vaccination. Vaccination was effective in eliminating the infection in most of the infected bulls, but cannot be recommended as the sole measure of control in infected herds.     

Drought as a modulator of plant–virus–vector interactions: Effects on symptom expression,plant immunity and vector behaviour

Plant–virus interactions are affected by environmental conditions that determine plant vulnerability to pathogens and the population dynamics of insect vectors. We hypothesize that drought enhances horizontal transmission by dampening the basal immunity of plants, which triggers symptom expression and vector manipulation. The potato yellow vein virus (PYVV) causes potato yellow vein disease (PYVD), a re-emerging epidemic of potato crops in South America, and is transmitted horizontally by the greenhouse whitefly (GWF), Trialeurodes vaporariorum (Hemiptera: Aleyrodidae), or vertically through infected seed tubers. We investigated the role of drought and temperature as modulators of PYVD symptom expression, plant immune response, and vector survival, development and host preference. We found that drought induced symptom expression, suppressed the salicylic acid pathway and increased PYVV replication. GWF survival was reduced on PYVV-infected hosts and development was slowest when they fed on plants with PYVD symptoms, which also triggered adults’ attraction to PYVV-infected plants. However, adults previously fed on infected plants showed the opposite effect, being more attracted to PYVV-free plants. We propose a theoretical model that explains the role of drought in modulating potato–PYVV–GWF interactions and provides new insights into plant–virus–vector coevolution.