Oxidation of cyclohexanol and cyclohexene with triazenido complexes of chromium immobilized in biosorption FAU supports

This work presents the recovery of biosorption supports as an alternative source of benign production of heterogeneous catalysts for oxidation reactions in mild conditions. Cr-containing FAU zeolite, in sodium form (NaY) and in proton form (HY), was recovered from biosorption studies and reused as support for the preparation of heterogeneous catalysts by the flexible ligand method, using 1,3-diphenyltriazene derivatives. Results showed that the ligand play an important role in the coordination of Cr inside the zeolite. The catalysts showed good activity for the oxidation of cyclohexanol, reaching a maximum of 63.5% conversion. Cr leaching was evaluated and it was found that the Cr-FAU supports lost some of the Cr into the reaction medium, whereas immobilization of Cr-complexes reduced the referred leaching. For the cyclohexene oxidation, a maximum 72.9% conversion was achieved with a HY zeolite-based catalyst.H. Figueiredo and B. Silva are thankful to the "FCT - Fundacao para a Ciencia e Tecnologia" for their respective research grants. IKB thanks FO' for the contract under the program Ciencia 2007. This work was partially funded by the Centre of Biological Engineering and the Centre of Chemistry (University of Minho, Portugal) through FCT strategic projects PEst-OE/EQB/LA0023/ 2013 and PEst-C/QUI/UI0686/2011 (nF-COMP-01-0124-FEDER022716), the Project "BioEnv - Biotechnology and Bioengineering for a sustainable world", REF. NORTE-07-0124-FEDER-000048, co-funded by the Programa Operacional Regional do Norte (ON.2 - 0 Novo Norte), QREN and FEDER, and by the Spanish Ministry of Science and Innovation (CTQ2008-04261/PPQ)

Bisphenol A exposure and cardiac electrical conduction in excised rat hearts

BACKGROUND: Bisphenol A (BPA) is used to produce polycarbonate plastics and epoxy resins that are widely used in everyday products, such as food and beverage containers, toys and medical devices. Human biomonitoring studies have suggested that a large proportion of the population may be exposed to BPA. Recent epidemiological studies have reported correlations between increased BPA urinary concentrations and cardiovascular disease; yet the direct effects of BPA on the heart are unknown. OBJECTIVES: The goal of our studies was to measure BPA\u27s effect (0.1-100 μM) on cardiac impulse propagation ex vivo, using excised whole hearts from adult rats. METHODS: We measured atrial and ventricular activation times during sinus and paced rhythms using epicardial electrodes and optical mapping of transmembrane potential. Atrioventricular activation intervals and epicardial conduction velocities were computed using recorded activation times. RESULTS: Cardiac BPA exposure resulted in prolonged PR segment and decreased epicardial conduction velocity (0.1 - 100 μM), prolonged action potential duration (1 - 100 μM) and delayed atrioventricular conduction (10 - 100 μM). Importantly, these effects were observed after acute exposure (≤ 15 min), underscoring the potential detrimental effects of continuous BPA exposure. The highest BPA concentration used (100 μM) resulted in prolonged QRS intervals, dropped ventricular beats and eventually resulted in complete heart block. CONCLUSIONS: Our results show that acute BPA exposure slows electrical conduction in excised hearts from female rats. These findings emphasize the importance of examining BPA\u27s effect on heart electrophysiology and determining whether chronic in vivo exposure can cause/exacerbate conduction abnormalities in patients with pre-existing heart conditions and other high-risk populations

Does α-synuclein have a dual and opposing effect in preclinical vs. clinical Parkinson's disease?

Abstractα-Synuclein gene (SNCA) multiplications cause familial parkinsonism and allele-length polymorphisms within the SNCA dinucleotide repeat REP1 increase the risk for developing Parkinson's disease (PD). Since SNCA multiplications increase SNCA expression, and REP1 genotypes that increase the risk of developing PD show increased SNCA expression in cell-culture systems, animal models, and human blood and brain, PD therapies seek to reduce SNCA expression. We conducted an observational study of 1098 PD cases to test the hypothesis that REP1 genotypes correlated with reduced SNCA expression are associated with better motor and cognitive outcomes. We evaluated the association of REP1 genotypes with survival free of Hoehn and Yahr stages 4 or 5 (motor outcome) and of Modified Telephone Interview for Cognitive Status score ≤27 or Alzheimer's Disease Dementia Screening Interview score ≥2 (cognitive outcome). Median disease duration at baseline was 3.3 years and median lag time from baseline to follow-up was 7.8 years. Paradoxically, REP1 genotypes associated with increased risk of developing PD and increased SNCA expression were associated with better motor (HR = 0.87, p = 0.046, covariate-adjusted age-scale analysis; HR = 0.85, p = 0.020, covariate-adjusted time-scale analysis) and cognitive outcomes (HR = 0.90, p = 0.12, covariate-adjusted age-scale analysis; HR = 0.85, p = 0.023, covariate-adjusted time-scale analysis). Our findings raise the possibility that SNCA has a dual, opposing, and time-dependent role. This may have implications for the development of therapies that target SNCA expression

Bipolar disorder with binge eating behavior: a genome-wide association study implicates PRR5-ARHGAP8

Bipolar disorder (BD) is associated with binge eating behavior (BE), and both conditions are heritable. Previously, using data from the Genetic Association Information Network (GAIN) study of BD, we performed genome-wide association (GWA) analyses of BD with BE comorbidity. Here, utilizing data from the Mayo Clinic BD Biobank (969 BD cases, 777 controls), we performed a GWA analysis of a BD subtype defined by BE, and case-only analysis comparing BD subjects with and without BE. We then performed a meta-analysis of the Mayo and GAIN results. The meta-analysis provided genome-wide significant evidence of association between single nucleotide polymorphisms (SNPs) in PRR5-ARHGAP8 and BE in BD cases (rs726170 OR=1.91, P=3.05E-08). In the meta-analysis comparing cases with BD with comorbid BE vs. non-BD controls, a genome-wide significant association was observed at SNP rs111940429 in an intergenic region near PPP1R2P5 (p=1.21E-08). PRR5-ARHGAP8 is a read-through transcript resulting in a fusion protein of PRR5 and ARHGAP8. PRR5 encodes a subunit of mTORC2, a serine/threonine kinase that participates in food intake regulation, while ARHGAP8 encodes a member of the RhoGAP family of proteins that mediate cross-talk between Rho GTPases and other signaling pathways. Without BE information in controls, it is not possible to determine whether the observed association reflects a risk factor for BE in general, risk for BE in individuals with BD, or risk of a subtype of BD with BE. The effect of PRR5-ARHGAP8 on BE risk thus warrants further investigation