Problematic rise of vitamin B6 supplementation overuse and potential risk to bariatric surgery patients.

OBJECTIVES: Due to the increased prevalence of obesity in the world, bariatric surgeries are on the rise and necessitate life-long surveillance for deficiencies; hence the recommended vitamin supplementation in these patients. However, inadequate multivitamin supplementation may induce vitamin B6 overload. METHODS: We reviewed all vitamin B6 dosages at the university hospitals of Poitiers, Tours, Bordeaux, and Limoges for the past 5 to 8 years. Analyses were performed by high-performance liquid chromatography, coupled with a fluorescence detector on whole blood samples. RESULTS: During the study period, there was an increase in the number of vitamin B6 dosages. Deficiencies were detected early in Poitiers and Limoges, but were negligible by 2020. However, during the same time period, the number of overdoses increased, reaching close to 40% of dosages at all centers. CONCLUSIONS: Pyridoxin overload is not possible through food-derived pyridoxin; hence, combined with the fact that most vitamin supplements contain vitamin B6, inadequate vitamin supplementation is likely the cause of the observed increase in overdoses. High doses of vitamin B6 can induce polyneuropathy, particularly targeting motor neurons; thus, the increase of overdoses is worrying. In light of the possible risks and the ease with which these could be averted (better formulation of supplements), the precaution principle requires a definition of clear guidelines for vitamin supplementation, especially in patients undergoing bariatric surgery.

Monitoring saltwater intrusion in Rupert Bay, Québec, Canada, after the partial diversion of a major tributary.

As part of a large hydroelectric project in northern Québec (Canada), a portion of the flow of the Rupert River was diverted toward the existing La Grande hydroelectric complex. As a result of the partial diversion, the discharge of the Rupert River at its mouth is reduced by an average of 50% annually. This corresponds to an 18% decrease in the total freshwater inflow into the bay and, thus, to a shift of the upstream limit of the saltwater intrusion in Rupert Bay. Changes in saltwater intrusion had been predicted numerically as part of the project's environmental impact assessment (EIA). In the project's conditions of authorization, monitoring the hydraulic conditions and the extent of saltwater intrusion in the Rupert Bay was required by government authorities. The objective of this paper is to present the results of this environmental monitoring and, more specifically, to validate the modifications predicted in the EIA in terms of both saltwater intrusion limit and hydraulic conditions in the Rupert Bay. Results obtained during 2 years of monitoring are within the predicted trends and order of magnitude of changes anticipated in the EIA. The results, thus, confirm that the shift of the upstream limit of the saltwater front along the channels of the bay was conservatively predicted by numerical modeling.

An interaction network predicted from public data as a discovery tool: application to the Hsp90 molecular chaperone machine.

Understanding the functions of proteins requires information about their protein-protein interactions (PPI). The collective effort of the scientific community generates far more data on any given protein than individual experimental approaches. The latter are often too limited to reveal an interactome comprehensively. We developed a workflow for parallel mining of all major PPI databases, containing data from several model organisms, and to integrate data from the literature for a protein of interest. We applied this novel approach to build the PPI network of the human Hsp90 molecular chaperone machine (Hsp90Int) for which previous efforts have yielded limited and poorly overlapping sets of interactors. We demonstrate the power of the Hsp90Int database as a discovery tool by validating the prediction that the Hsp90 co-chaperone Aha1 is involved in nucleocytoplasmic transport. Thus, we both describe how to build a custom database and introduce a powerful new resource for the scientific community.