Medical education programs in North America are often based on the adult education theory of self-directed learning (SDL). Many kinds of SDL have been introduced into preclerkship education, clerkships, residency training, and continuing medical education. The first goal of this paper was to review SDL in North American medical education. The second goal was to describe an example of community-based clerkship in which SDL was applied in the department of family and community medicine of the University of Toronto. A third goal was to give three recommendations for Japanese clinical clerkships. The first recommendation is the effect of the learning contract. The second is that the preceptor should give quick and frequent feedback to students and that a useful Japanese feedback device should be developed with information technology. The third recommendation is that a new curriculum combining community-based education for students with continuing medical education for doctors is necessary to improve Japanese medical education.

BACKGROUND: Pyrethroid (PYR) insecticides are widely used for controlling various pests. There are two types that differ in terms of usage: agricultural-purpose PYR (agriculture-PYR) and hygiene purpose PYR (hygiene-PYRs). Few studies exist on the exposure to these chemicals in small children. In this study, we conducted biomonitoring of urinary pyrethroid metabolites in 1.5-year-old children throughout the year. METHODS: Study subjects were 1075 children participating in an Aichi regional sub-cohort of the Japan Environment and Children's Study as of 18-month health check-up. The concentrations of four specific hygiene-PYR metabolites including 2,3,5,6-tetrafluoro-1,4-benzenedimethanol (HOCH₂-FB-Al), and five common metabolites of hygiene- and agriculture-PYRs including 3-phenoxybenzoic acid (3PBA) and cis- and trans-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropane-1-carboxylic acid (DCCA), were measured in urine samples extracted from soiled diapers using a triple quadrupole gas chromatograph-mass spectrometer. RESULTS: The highest detection frequencies were for 3PBA, followed by DCCA, 1R-trans-chrysanthemum dicarboxylic acid, and HOCH₂-FB-Al. Among the six metabolites, urinary concentrations were seasonally varied. However, this variation was not observed in the most studied PYR metabolite, 3PBA. Spearman's correlation analysis demonstrated a significant positive correlation between FB-Al and DCCA (r = 0.56) and HOCH₂-FB-Al and 4-methoxymethyl-2,3,5,6-tetrafluorobenzyl alcohol (r = 0.60). CONCLUSIONS This biomonitoring survey found widespread and seasonally specific exposure to multiple hygiene- and agriculture-PYRs in 1.5-year-old Japanese children.
Agriculture ; Child, Preschool ; Environmental Exposure/analysis* ; Humans ; Infant ; Insecticides ; Japan ; Mass Spectrometry ; Pyrethrins/urine*

BACKGROUND: Glyphosate and its salt formulations are nonselective herbicides that have been extensively used worldwide, both for residential and agricultural purposes. The possible carcinogenicity and teratogenicity of glyphosate remain to be elucidated. We developed a sensitive and high-throughput analytical method for urinary glyphosate using liquid chromatography-tandem mass spectrometry with the aim of contributing to glyphosate exposure assessment in epidemiological studies. METHODS: After urine dilution (creatinine matching dilution to 0.05 g creatinine/L), glyphosate was extracted using two types of solid phase extraction columns (SCX and NH2) with automated sample preparation instruments. The eluate was dried and dissolved in the mobile phase, followed by liquid chromatography-tandem mass spectrometry analysis. The optimized method was applied to urine samples obtained from 54 Japanese adults and children. RESULTS: The results from the validation study demonstrated good recoveries (91.0-99.6%), within- and between-run precisions (< 15%), low detection limits (0.1 μg/L), and lower limit of quantification (0.3 μg/L). The detection frequency and median concentration of the urinary glyphosate in Japanese subjects were 59% and 0.25 μg/L (0.34 μg/g creatinine). CONCLUSIONS Our reliable determination method was successful in measuring urinary glyphosate concentration. Moreover, this is the first biomonitoring report of urinary glyphosate levels in the Japanese general population.
Adult ; Aged ; Chromatography, Liquid/methods* ; Female ; Glycine/urine* ; Humans ; Male ; Middle Aged ; Solid Phase Extraction/methods* ; Tandem Mass Spectrometry/methods*