Optimization of the Biocatalysis for D-DIBOA Synthesis Using a Quick and Sensitive New Spectrophotometric Quantification Method.

D-DIBOA (4-hydroxy-(2H)-1,4-benzoxazin-3-(4H)-one) is an allelopathic-derived compound with interesting herbicidal, fungicidal, and insecticide properties whose production has been successfully achieved by biocatalysis using a genetically engineered Escherichia coli strain. However, improvement and scaling-up of this process are hampered by the current methodology for D-DIBOA quantification, which is based on high-performance liquid chromatographic (HPLC), a time-consuming technique that requires expensive equipment and the use of environmentally unsafe solvents. In this work, we established and validated a rapid, simple, and sensitive spectrophotometric method for the quantification of the D-DIBOA produced by whole-cell biocatalysis, with limits of detection and quantification of 0.0165 and 0.0501 µmol·mL-1 respectively. This analysis takes place in only a few seconds and can be carried out using 100 µL of the sample in a microtiter plate reader. We performed several whole-cell biocatalysis strategies to optimize the process by monitoring D-DIBOA production every hour to keep control of both precursor and D-DIBOA concentrations in the bioreactor. These experiments allowed increasing the D-DIBOA production from the previously reported 5.01 mM up to 7.17 mM (43% increase). This methodology will facilitate processes such as the optimization of the biocatalyst, the scaling up, and the downstream purification.

Road accidents and business cycles in Spain.

This paper explores the causes behind the downturn in road accidents in Spain across the last decade. Possible causes are grouped into three categories: Institutional factors (a Penalty Point System, PPS, dating from 2006), technological factors (active safety and passive safety of vehicles), and macroeconomic factors (the Great recession starting in 2008, and an increase in fuel prices during the spring of 2008). The PPS has been blessed by incumbent authorities as responsible for the decline of road fatalities in Spain. Using cointegration techniques, the GDP growth rate, the fuel price, the PPS, and technological items embedded in motor vehicles appear to be statistically significantly related with accidents. Importantly, PPS is found to be significant in reducing fatal accidents. However, PPS is not significant for non-fatal accidents. In view of these results, we conclude that road accidents in Spain are very sensitive to the business cycle, and that the PPS influenced the severity (fatality) rather than the quantity of accidents in Spain. Importantly, technological items help explain a sizable fraction in accidents downturn, their effects dating back from the end of the nineties.

Mental health outcomes of cocaine-exposed children at 6 years of age.

OBJECTIVE: To assess 6-year-old cocaine- and noncocaine-exposed children's mental health outcomes controlling for potential confounders. METHODS: The sample consisted of 322 children [169 cocaine exposed (CE) and 153 noncocaine exposed (NCE)] enrolled in a longitudinal study since birth. At age 6, children were assessed for mental health symptoms using the Dominic Interactive (DI), a child self-report measure, and the Child Behavior Checklist (CBCL), a caregiver report of behavioral problems. RESULTS: CE children were more likely to self-report symptoms in the probable clinical range for oppositional defiant disorder (ODD) and attention deficit hyperactivity disorder (ADHD). In contrast, prenatal cocaine exposure was not related to child behavior based on the CBCL. After control for exposure, CE children in adoptive or foster care were rated as having more problems with aggression, externalizing behaviors, and total behavioral problems than NCE children and CE children in maternal or relative care. Also, CE children in adoptive or foster care self-reported more externalizing symptoms than CE children in maternal or relative care and NCE children. Findings could not be attributed to caregiver intelligence or depressive symptoms, or to the quality of the home environment. CONCLUSIONS: CE children report more symptoms of ODD and ADHD than nonexposed children. Adoptive or foster caregivers rated their CE children as having more behavioral problems than did maternal or relative caregivers of CE children or parents of NCE children. Although further studies are needed to understand the basis for the more negative ratings by adoptive or foster caregivers of their CE children, the self-report of CE children indicates a need for psychological interventions.

Psychosocial profiles of older adolescent MDMA users.

PURPOSE: Using a case-control design, patterns of drug use, psychological symptoms, and behavioral characteristics associated with 3,4-methylenedioxymethamphetamine (MDMA ) use were surveyed in a sample of older adolescents (median age 20). METHODS: One hundred (42 MDMA users; 58 non-MDMA users) older adolescents were recruited using the "snowball" technique and interviewed regarding their use of MDMA and other drugs. The Brief Symptom Inventory (BSI), the Problem Oriented Screening Instrument for Teenagers (POSIT), the HIV/sexually transmitted diseases (STD) risk scale, and the Childhood Trauma Questionnaire (CTQ) were also administered. RESULTS: MDMA users were more likely to use other substances, endorse more symptoms of psychological distress, and had more problems in functional lifestyle areas. They also reported more childhood experiences of physical abuse, emotional neglect, and physical neglect than non-MDMA users. MDMA users also reported more sexually risky behaviors. CONCLUSIONS: Occasional MDMA use among older adolescents was associated with polydrug use, multiple social difficulties, psychological symptoms, and health risk behaviors. Further research is warranted to understand the long term psychosocial consequences of chronic MDMA and polydrug usage.