Methylmercury Determination in Fish by Direct Mercury Analyzer.

BACKGROUND: There are two methods for quantifying methylmercury (MeHg) in fish using GC-electron capture detection (ECD): AOAC INTERNATIONAL Official Method 988.11 and the Korean Food Code (KFC) method. Both of these methods consume a large amount of chemicals and require long pretreatment times because of several complicated MeHg extraction steps. OBJECTIVE: In this study, a new method for the simple and rapid determination of MeHg in fish has been developed. The method is based on the investigation of oxygen combustion-gold amalgamation using a direct mercury analyzer (DMA) after the complete removal of MeHg by organic extraction and back-extraction to an aqueous medium. METHODS: The DMA is suitable for the analysis of both solid and liquid materials and has a good detection limit. The developed method was validated by comparing the MeHg recoveries (%) of both certified reference materials and the market-purchased fish samples with the MeHg concentration obtained using the KFC method. RESULTS: The following parameters pertaining to the developed method were established: detection limit, 1.02 µg/kg; LOQ, 3.09 µg/kg; linearity (r), 0.9998; range, 0.1-300 µg/kg; and recovery, 95-97%. CONCLUSIONS: Our method is a promising alternative by virtue of its much simpler and faster sample pretreatment procedure, with a MeHg recovery as high as that of the KFC method. HIGHLIGHTS: The developed method enables the simultaneous analysis of total Hg and MeHg with only DMA equipment.

A randomized controlled trial of an internet-based mentoring program for type 1 diabetes patients with inadequate glycemic control.

BACKGROUND: To determine whether an internet-based mentoring program can improve glycemic control in subjects with type 1 diabetes mellitus (T1DM). METHODS: Subjects with T1DM on intensive insulin therapy and with hemoglobin A1c (HbA1c) ≥8.0% were randomized to mentored (glucometer transmission with feedback from mentors) or control (glucometer transmission without feedback) groups and were examined for 12 weeks. Five mentors were interviewed and selected, of which two were T1DM patients themselves and three were parents with at least one child diagnosed with T1DM since more than 5 years ago. RESULTS: A total of 57 T1DM adult subjects with a mean duration after being diagnosed with diabetes of 7.4 years were recruited from Samsung Medical Center. Unfortunately, the mentored group failed to show significant improvements in HbA1c levels or other outcomes, including the quality of life, after completion of the study. However, the mentored group monitored their blood glucose (1.41 vs. 0.30) and logged into our website (http://ubisens.co.kr/) more frequently (20.59 times vs. 5.07 times) than the control group. CONCLUSION: A 12-week internet-based mentoring program for T1DM patients with inadequate glycemic control did not prove to be superior to the usual follow-up. However, the noted increase in the subjects' frequency of blood glucose monitoring may lead to clinical benefits.