EDTA-assisted phytoextraction of lead and cadmium by Pelargonium cultivars grown on spiked soil

The aim of this study was to assess EDTA-assisted Pb and Cd phytoextraction potential of locally grown Pelargonium hortorum and Pelargonium zonale. Plants were exposed to different levels of Pb (0–1500?mg kg^?1) and Cd (0–150?mg kg^?1) in the absence or presence of EDTA (0–5?mmol kg^?1). P. hortorum and P. zonale accumulated 50.9% and 42.2% higher amount of Pb in shoots at 1500?mg kg^?1 Pb upon addition of 5?mmol kg^?1 EDTA. Plant dry biomass decreased 46.8% and 64.3% for P. hortorum and P. zonale, respectively at the combination of 1500?mg kg^?1 Pb and 5?mmol kg^?1 EDTA. In Cd and EDTA-treated groups, P. hortorum and P. zonale accumulated 2.7 and 1.6-folds more Cd in shoots at 4 and 2?mmol kg^?1 EDTA, respectively, in 150?mg Cd kg^?1 treatment. Plant dry biomass of P. hortorum and P. zonale was reduced by 46.3% and 71.3%, respectively, in soil having 150?mg Cd kg^?1 combined with 5?mmol kg^?1 EDTA. Translocation factor and enrichment factor of both plant cultivars at all treatment levels were >1. Overall, the performance of P. hortorum was better than that of P. zonale for EDTA-assisted phytoextraction of Pb and Cd.     

Crystal Structure of the Homing Endonuclease I-CvuI Provides a New Template for Genome Modification

Homing endonucleases recognize and generate a DNA double-strand break, which has been used to promote gene targeting. These enzymes recognize long DNA stretches; they are highly sequence-specific enzymes and display a very low frequency of cleavage even in complete genomes. Although a large number of homing endonucleases have been identified, the landscape of possible target sequences is still very limited to cover the complexity of the whole eukaryotic genome. Therefore, the finding and molecular analysis of homing endonucleases identified but not yet characterized may widen the landscape of possible target sequences. The previous characterization of protein-DNA interaction before the engineering of new homing endonucleases is essential for further enzyme modification. Here we report the crystal structure of I-CvuI in complex with its target DNA and with the target DNA of I-CreI, a homologue enzyme widely used in genome engineering. To characterize the enzyme cleavage mechanism, we have solved the I-CvuI DNA structures in the presence of non-catalytic (Ca²⁺) and catalytic ions (Mg²⁺). We have also analyzed the metal dependence of DNA cleavage using Mg²⁺ ions at different concentrations ranging from non-cleavable to cleavable concentrations obtained from in vitro cleavage experiments. The structure of I-CvuI homing endonuclease expands the current repertoire for engineering custom specificities, both by itself as a new scaffold alone and in hybrid constructs with other related homing endonucleases or other DNA-binding protein templates.     

Distribution of ABCB1, CYP3A5, CYP2C19, and P2RY12 gene polymorphisms in a Mexican Mestizos population

The aim of the present study was to establish the gene frequency of six polymorphisms of the ABCB1, CYP3A5, CYP2C19, and P2RY12 genes in a population resident of Mexico City. The proteins encoded by these genes have been associated with the absorption, and biotransformation of clopidogrel. The ABCB1 T3435C, CYP3A5 V3* A6986G, P2RY12 G52T, P2RY12 C34T, CYP2C19 V2* and V3* (positions G681A and G636A, respectively), polymorphisms were analyzed by 5′ exonuclease TaqMan genotyping assays in a group of 269 healthy unrelated Mexican Mestizo individuals. The CYP2C19 V3* G636A polymorphism was not detected in the Mexican Mestizos population. However, the studied population presented significant differences (P < 0.05) in the distribution of the T3435C, A6986G, G681A, G52T and C34T polymorphisms when compared to reported frequencies of Amerindian of South America, Caucasian, Asian, and African populations. In summary, the distribution of the ABCB1, CYP3A5, CYP2C19, and P2RY12 gene polymorphisms distinguishes to the Mexican Mestizos population from other ethnic groups.     

Long-Term Sickness Absence Due to Mental Disorders Is Associated with Individual Features and Psychosocial Work Conditions

Aims

Sickness absence is a socioeconomic global burden. In Brazil, mental disorders are the third leading cause of social security benefits payments. The aim of the present study was to compare factors associated with long-term sickness absence between workers who claimed social benefits due to mental disorders or by other causes. We investigated individual features and occupational characteristics. In addition, we evaluated psychosocial factors at work assessed by the Demand-Control-Support (DCS) and Effort-Reward Imbalance (ERI) models, and whether they were associated with long-term sickness absence due to mental disorders (LTSA-MD).

Methods

The present case-control study was conducted in São Paulo, Brazil. The sample (n = 385) included workers on sick leave for more than 15 days. Cases were the participants with disabling psychiatric illnesses, and controls were the ones with other disabling diseases. Interviews were conducted to assess individual features (sociodemographic data, health habits/lifestyle, health conditions) and occupational characteristics. The participants'' perception of exposure to dimensions of the DCS and ERI models was also recorded. Multiple logistic regressions were performed to evaluate the association between independent variables and LTSA-MD.

Results

All the regression analyses showed that LTSA-MD was associated with female sex, self-reported white skin color, higher education level, high tobacco consumption, high alcohol intake, two or more comorbidities, exposure to violence at work, high job strain and low social support at work, effort-reward imbalance and high overcommitment to work. LTSA-MD was associated with separate and combined DCS and ERI stress models.

Conclusions

Individual features and work conditions were associated with LTSA-MD. Combined analysis of stress models showed that psychosocial factors at work were significantly associated with LTSA-MD. Resourceful use of this information may contribute to the implementation of preventive actions and strategies to facilitate return to work targeting the populations most susceptible to mental disorders.     

Proteasome and antioxidant responses in Cottus gobio during a combined exposure to heat stress and cadmium

Temperature and trace metals are common environmental stressors, and their importance is increasing due to global climate change and anthropogenic pollution. Oxidative damage and antioxidant properties have been studied in liver and gills of the European bullhead (Cottus gobio) subjected to cadmium (CdCl(2) at nominal concentrations of 0.01 and 1mg/L) for 4 days at either 15°C or 21°C. First, exposure to 1mg Cd/L induced a high mortality rate (67%) in fish held at 21°C. Regarding the antioxidant enzymes, exposure to 0.01 mg Cd/L significantly increased the activity of superoxide dismutase (SOD) and decreased the activity of glutathione reductase (GR) in liver, independently of heat stress. In gills, exposure to 21°C resulted in a significantly increased activity of glutathione peroxidase (GPx), whereas the activity of glutathione S-transferase (GST) was significantly reduced as compared to fish exposed to 15°C. Furthermore, regardless of Cd stress, exposure to elevated temperature resulted in a significant decrease of lipid peroxidation (LPO) level in liver and in a significant increase in the activity of chymotrypsin-like 20S proteasome in both studied tissues of C. gobio. Overall, the present results indicated that elevated temperature and cadmium exposure independently influenced the antioxidant defense system in bullhead with clear tissue-specific and stress-specific antioxidant responses. Further, elevated temperature affected the hepatic lipid peroxidation and the activity of 20S proteasome in both tissues.     

Pharmacological maintenance of protein homeostasis could postpone age-related disease

Over the last 10 years, various screens of small molecules have been conducted to find long sought interventions in aging. Most of these studies were performed in invertebrates but the demonstration of pharmacological lifespan extension in the mouse has created considerable excitement. Since aging is a common risk factor for several chronic diseases, there is a reasonable expectation that some compounds capable of extending lifespan will be useful for preventing a range of age‐related diseases. One of the potential targets is protein aggregation which is associated with several age‐related diseases. Genetic studies have long indicated that protein homeostasis is a critical component of longevity but recently a series of chemicals have been identified in the nematode Caenorhabditis elegans that lead to the maintenance of the homeostatic network and extend lifespan. Herein we review these interventions in C. elegans and consider the potential of improving health by enhancing protein homeostasis.     

Proteomic analysis of blood cells in fish exposed to chemotherapeutics: evidence for long term effects

Proteomics technology are increasingly used in ecotoxicological studies to characterize and monitor biomarkers of exposure. The present study aims at identifying long term effects of malachite green (MG) exposure on the proteome of peripheral blood mononuclear cells (PBMC) from the Asian catfish, Pangasianodon hypophthalmus. A common (0.1 ppm) concentration for therapeutic treatment was applied twice with a 72 h interval. PBMC were collected directly at the end of the second bath of MG (T1) and after 1 month of decontamination (T2). Analytical 2D-DIGE gels were run and a total of 2551±364 spots were matched. Among them, MG induced significant changes in abundance of 116 spots with no recovery after one month of decontamination. Using LC-MS/MS and considering single identification per spot, we could identify 25 different proteins. Additionally, MG residues were measured in muscle and in blood indicating that leuco-MG has almost totally disappeared after one month of decontamination. This work highlights long term effects of MG treatment on the PBMC proteome from fish intended for human consumption.