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Extreme cold events can have several consequences in different sectors, including human health, infrastructure, agriculture, and the economy. The frost events that affect central and northeastern Argentina are associated with stationary Rossby waves triggered by tropical heat sources and convection, which result in intense polar air advection. However, the processes responsible for these cold events include complex interactions between these wave trains and mechanisms at different atmospheric scales, such as the Madden–Julian Oscillation (MJO), which can alter the temperature patterns. This study investigates the impacts of the MJO on air temperature and associated circulation in years with extreme occurrence frequency of cold events in central southern South America during the winter. The results showed that the MJO convection can enhance or weaken the temperature anomalies during winters with a maximum and minimum frequency of generalized frosts (GF) occurrence due to Rossby wave train propagation triggered in the tropical region. Moreover, the effect on the anomaly patterns in these events depends on the MJO phase. Our analysis shows that individual MJO phases can modulate the temperature anomalies even in an unfavorable basic state (as in winters with an extreme frequency of GF and emphasizes the importance of considering the MJO in the predictions of the temperature anomalies associated with GF over southeastern South America. [ABSTRACT FROM AUTHOR]

Flavin-containing monooxygenase 3 (FMO3) is a polymorphic drug metabolizing enzyme associated with the genetic disorder trimethylaminuria. We phenotyped a white Argentinian 11-year-old girl by medical sensory evaluation. After pedigree analysis with her brother and parents, this proband showed to harbor a new allele p.(P73L; E158K; E308G) FMO3 in trans configuration with the second new one p.(F140S) FMO3. Recombinant FMO3 proteins of the wild-type and the novel two variants underwent kinetic analyses of their trimethylamine N-oxygenation activities. P73L; E158K; E308G and F140S FMO3 proteins exhibited moderately and severely decreased trimethylamine N-oxygenation capacities (~50% and ~10% of wild-type FMO3, respectively). Amino acids P73 and F140 were located on the outer surface region in a crystallographic structure recently reported of a FMO3 analog. Changes in these positions would indirectly impact on key FAD-binding residues. This is the first report and characterization of a patient of fish odor syndrome caused by genetic aberrations leading to impaired FMO3-dependent N-oxygenation of trimethylamine found in the Argentinian population. We found novel structural determinants of FAD-binding domains, expanding the list of known disease-causing mutations of FMO3. Our results suggest that individuals homozygous for any of these new variants would develop a severe form of this disorder., Competing Interests: Declaration of competing interest The authors declare that there are no conflicts of interest., (Copyright © 2020 The Japanese Society for the Study of Xenobiotics. Published by Elsevier Ltd. All rights reserved.)