Effects of occupational environmental controls and work management on chromosomal damage in dental technicians in Japan.

Dental technicians use various materials, particularly metal alloys and monomers and polymers based on methylmethacrylate. Environmental hygiene issues surrounding the work of dental technicians have been recognized. Despite the need for observance of occupational environmental controls and work management, compliance among dental laboratories appears to be low. We evaluated the relationship between genotoxic effects in dental technicians and occupational environmental controls and work management. We used cytokinesis-blocked micronuclei (CB-MN) frequencies in peripheral lymphocytes and metal levels in scalp hair. We also assessed nutritional factors related to anti-genotoxic effects using a self-administered brief diet history questionnaire. Study subjects were 54 male dental technicians and 38 male clerical workers. The parameters on the micronuclei (MN) frequency in dental technicians and clerical workers were analyzed by forward stepwise multiple regression analyses. Age (P < 0.01, ß = 0.561), occupation as a dental technician (P < 0.01, ß = 0.636) and aluminum levels in scalp hair (P < 0.05, ß = 0.213) were risk factors that significantly increased MN frequency. The significant parameters on the MN frequency in dental technicians were observance of hand-washing as work management (P < 0.01, ß = -0.304), work period (P < 0.01, ß = 0.509), germanium levels in scalp hair (P < 0.01, ß = -0.314) and workplace (P < 0.05, ß = 0.235). To avoid genotoxic effects, observance of occupational environmental controls and work management is necessary for dental technicians.

[Clinical evaluation of a novel multiplex HPV genotyping reagent using the luminex xMAP technology].

Of the more than 100 strains of human papillomavirus (HPV) reported to date, 13 strains are clinically significant due to the highly associated risk of cervical cancer. HPV test reagents are currently being developed to aid detection of these strains. The present study compared a novel HPV genotyping reagent using a Luminex device, which enables simultaneous quantitation of multiple targets using fluorescent beads, and gene-specific multiplex polymerase chain reaction (Luminex method) with approved in vitro diagnostics. Subjects comprised 256 patients examined at our hospital for either secondary cervical cancer testing or follow-up (mean age, 40 years; age range, 20-85 years) and specimens were obtained using a cervical brush and lavage fluid. The HPV-positive rate with the Luminex method was 51.4%(132/256), of which single and multiple strain infections constituted 65.9% (87/132) and 34.1% (45/132), respectively. Correlation testing of 50 positive and 50 negative Luminex method specimens was conducted using the HPV DNA Hybrid Capture II (HCII), revealing high overall (97%[97/100]), positive(100% [47/47]) and negative(94.3% [50/53]) concordance rates. Correlation was also high for the Clinichip HPV (Clinichip), with overall, positive and negative concordance rates of 98% (98/100), 100%(48/48) and 96.2%(50/52), respectively. Furthermore, the detection concordance rate with the Clinichip was 95.8% (46/48). Sequencing of the seven specimens showing result discrepancies (HCII, n = 3; Clinichip, n = 4) confirmed concordance with the Luminex method results in all cases, indicating the validity of the present method. The present findings suggest that the Luminex method has sufficient response capability for clinical application.