Influences of gonad developmental stage on ovary selenium concentrations in fish-implications for ovary selenium monitoring.

Monitoring selenium (Se) concentrations in fish ovaries is an important tool for evaluating the ecological risk posed by Se in aquatic systems. Most guidance recommends sampling fish ovaries as closely as possible to when fish spawn on the premise that Se is mobilized from the liver to the ovary during vitellogenesis, and therefore, sampling ovaries during the early phases of oocyte maturation may underestimate egg Se concentrations at the time of spawning. In this study, we evaluated ovary Se data from two species with synchronous oocyte development (Ptychocheilus oregonensis and Prosopium williamsoni), one species with asynchronous oocyte development (Richardsonius balteatus), and one where the mode of development is unclear (Mylocheilus caurinus).

Tight Blood-Glucose Control without Early Parenteral Nutrition in the ICU.

Background: Randomized, controlled trials have shown both benefit and harm from tight blood-glucose control in patients in the intensive care unit (ICU). Variation in the use of early parenteral nutrition and in insulin-induced severe hypoglycemia might explain this inconsistency.

Methods: We randomly assigned patients, on ICU admission, to liberal glucose control (insulin initiated only when the blood-glucose level was >215 mg per deciliter [>11.

Maternal Transfer and Effects of Selenium on Early Life Stage Development of Redside Shiner (Richardsonius balteatus).

Maternal transfer of selenium (Se) to developing fish eggs during vitellogenesis can cause larval deformity and mortality. Previous studies have shown wide variation among fish species in both the magnitude of maternal transfer (exposure) and the egg Se concentration causing effects (sensitivity). We studied maternal transfer and effects of Se on early life stage development, survival, and growth of redside shiner (Richardsonius balteatus), a small-bodied cyprinid that has been reported to have relatively high ovary:muscle Se concentration ratios.

The association of hypoglycemia with outcome of critically ill children in relation to nutritional and blood glucose control strategies.

Background: Withholding parenteral nutrition (PN) until one week after PICU admission facilitated recovery from critical illness and protected against emotional and behavioral problems 4 years later. However, the intervention increased the risk of hypoglycemia, which may have counteracted part of the benefit. Previously, hypoglycemia occurring under tight glucose control in critically ill children receiving early PN did not associate with long-term harm.

Analysis of Selenium in Fish Tissue: An Interlaboratory Study on Weight Constraints.

Environmental monitoring programs that target fish tissues for selenium (Se) analysis present unique sampling and analytical challenges. Selenium monitoring programs ideally focus on egg/ovary sampling but frequently sample multiple tissues with varying lipid content, often target small-bodied fish species because of their small home ranges, and require reporting in units of dry weight. In addition, there is a growing impetus for nonlethal tissue sampling in fish monitoring.