Selenium-enriched yeast (selenium yeast) are one of the most popular sources of selenium supplementation used in the agriculture and human nutritional supplements industries. To enhance the production efficiency of selenium yeast, we sought to develop a method to identify, and ultimately select for, strains of yeast with enhanced selenium accumulation capabilities. Selenite resistance of four genetically diverse strains of Saccharomyces cerevisiae was assayed in various conditions, including varying carbon sources, nitrogen sources, and phosphate amounts, and they were correlated with selenium accumulation in a commercially relevant selenium-containing growth medium. Glycerol- and selenite-containing media was used to select for six yeast isolates with enhanced selenite resistance. One isolate was found to accumulate 10-fold greater selenium (0.13 to 1.4 mg Se g−1 yeast) than its parental strain. Glycerol- and selenium-containing medium can be used to select for strains of yeast with enhanced selenium accumulation capability. The methods identified can lead to isolation of industrial yeast strains with enhanced selenium accumulation capabilities that can result in greater cost efficiency of selenium yeast production. Additionally, the selection method does not involve the construction of transgenic yeast, and thus produces yeasts suitable for use in human food and nutrient supplements.

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Background: Clinical decision making for pediatric neck trauma is challenging because data and reports are sparse. We present a case report showing current recommendations for managing pediatric neck injuries. Case Presentation: This is the case of an 11-year-old boy who presented to our Level I trauma center after a slip and fall on a metal boat cleat (metal fixture used to secure rope). He suffered a penetrating injury to his neck, requiring operative exploration. This case report provides an overview on the rare incidence of pediatric penetrating neck trauma and treatment options. Conclusion: This case highlights penetrating neck injuries, which are uncommon in the pediatric population. This case report is unusual due to the method of injury and nature of the object. Neck trauma via a metal boat cleat is particularly rare. A comprehensive understanding of the anatomy of the neck, mechanism of injury, thorough clinical examination, and proper workup are essential to providing effective care.