The number of fatalities in Japan attributable to lung cancer exceeded 50000 in 2001. It is socially desirable that various markers, which can be utilized for the prevention of lung cancer, be established. We believe that smoking or exposure to carcinogens in air induces mutations in bronchial and alveolar epithelia, leading to the development of lung cancer. It would be useful to have markers of individual differences in susceptibility to chemical carcinogen-induced lung cancer 1) to identify genetic polymorphisms of enzymes metabolizing chemical carcinogens and 2) to investigate the expression of enzymes metabolizing chemical carcinogens. In this paper, we review CYP expression in the bronchial epithelium. CYP1, CYP2 and CYP3 are expressed in the bronchial epithelium. We also show the relationship between the genetic polymorphisms of cytochrome P450 (CYP) and a person’s susceptibility to chemical carcinogen-induced lung cancer. We demonstrate the relationship between cigarette consumption and the CYP expression profile in the bronchial epithelium. To maintain and promote public health, we must apply evidence, such as CYP polymorphisms and CYP profiles to disease prevention and also to aggressively advance evidence-based prevention (EBP) of lung cancer.

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Toxic effects on eyes result from exposure to pesticides via inhalation, ingestion, dermal contact and ocular exposure. Exposure of unprotected eyes to pesticides results in the absorption in ocular tissue and potential ocular toxicity. Recent literature on the risks of ocular toxicity from pesticide exposure is limited.
Ocular toxicity from pesticide exposure, including the dose-response relationship, has been studied in different animal species. Cholinesterase enzymes have been detected in animal ocular tissue, with evidence of organophosphate-induced inhibition. Pathological effects of pesticides have been observed in conjunctiva, cornea, lens, retina and the optic nerve. Pesticide exposure has been associated with retinopathy in agricultural workers and wives of farmers who used pesticides. Saku disease, an optico-autonomic peripheral neuropathy, has been described in Japan in people living in an area where organophosphates were used. Pesticide exposure is also associated with abnormal ocular movements.
Progressive toxic ocular effects leading to defective vision are a serious health concern. Agricultural workers are at high risk of exposure to pesticides and associated ocular toxicity. Primary prevention is the appropriate method of protecting eyes from pesticide-related damage. This includes improved eye safety and care in workplaces, and effective pesticide regulation for maintenance of public eye health.

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Objectives: To investigate the dependency of temporary threshold shift of vibratoty sensation (TTS_v) in fingertip on hand-arm vibration exposure period.
Methods: Six healthy students were instructed to grip a vibrating or nonvibrating handle in the experimental room. The gripping force was 40 N. The vibratory sensation threshold at 125 Hz was measured before and after the exposure in the exposed middle fingertip. The exposure vibration was vertical and the 1/3 octave-band vibration with had a central frequency of 200 Hz and an intensity of 39.2 m/s². The exposure periods were 8, 15, 30, 60, 120, 240 and 600 s. TTS_{v, t} was evaluated as the difference in vibratory sensation threshold between immediately before and t seconds after the exposure.
Results: TTS_v recovered exponentially as in several previous studies and its use enabled us to estimate the time constant and TTS_{v, 0}. TTS_{v, 0} with vibration exposure was significantly larger than that without it. The regression analysis of the relationship between vibration exposure period (T) and TTS_{v, 0} (T) for each subject confirmed the good fit of the equation TTS_{v, 0} (T) = B₀ + B₁ * Log₁₀ (T), where B₀ and B₁ are the calculated constants (adjusted R² = 0.56 − 0.87). The time constants did not show such a clear dose effect relationship of exposure period as TTS_{v, 0}.
Conclusion: The dependency of TTS_{v, 0} on vibration exposure period was asymptotically proportional to the logarithm of gripping period. To more quantitatively confirm the relationship of the time constants for recovering time course of TTS_v, it maybe necessary to improve the measurement method for TTS_v.

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Objective: To investigate the personal features associated with dropout from regular outpatient care among persons with type 2 diabetes mellitus (DM).
Methods: A total of 160 DM patients were enrolled in the study. As a retrospective analysis, outpatient’s clinical characteristics, lifestyle, or social features were gathered from their medical records or interview sheets. All the subjects were divided into two groups by adherence to diabetic care, namely, ‘dropout case’ (DC) or ‘ongoing case’ (OC), and were subjected to comparative analysis. We called the patients who did not receive outpatient treatment from the clinic on a regular basis, including treatment from other clinics or dropout of diabetic care, as DC. In contrast, patients who regularly visited the clinic were defined as OC. An unconditional multiple logistic regression analysis was performed to analyze the association of adherence to diabetic care with several personal features.
Results: Sixty-eight of 160 subjects (42.5%) were recognized as DC. The remaining 92 subjects (57.5%) were considered as OC. Young age (p=0.045), low plasma glucose (p=0.005) and hemoglobin A1c (HbA1c) levels (p=0.005), nonmedication (p<0.001) and no past history of DM (p=0.007) at the initial visit were the features related to dropout by crude analysis. Even after adjustment for age and gender by multivariate analysis, there remained significant inverse associations of dropout with HbA1c level, medical treatment (oral agents or insulin) and previous DM history. Neither occupation, distance from residence to clinic, smoking habit nor drinking habit was associated with dropout. Dropout mostly occurred after the initial or second visit.
Conclusions: A mild condition of DM may be related to dropout from regular outpatient care. It may be necessary to clearly show the objectives and importance of regular visit to an outpatient clinic for diabetic care, particularly for screened mild DM cases in public health activities.

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Objectives: Ketamine hydrochloride (KT) is a secondary amine that has been safely used as an injectable anesthetic and analgesic to avoid the production of nitroso compounds in the stomach. However, ketamine in the tablet form has recently become an abused, recreational drug. The aim of this study was to investigate the genotoxic effects of N-nitrosoketamine (NKT) and KT on the basis of an in vitro micronucleus (MN) test using a Chinese hamster lung fibroblast cell line (CHL/IU).
Methods: NKT was synthesized from KT in our laboratory. In the MN tests, CHL/IU cells were continuously treated with either NKT or KT for 24, 48, or 72 hours without the S9 mix. The cells were also treated with NKT or KT with or without the S9 mix for 6 hours, followed by a recovery period of 18, 42, or 66 hours (short-term treatment). The results were considered to be statistically significant when the p-values of both Fisher's exact test and the trend test were less than 0.05.
Results: After the short-term treatment with either NKT or KT with and without the S9 mix, the frequency of micronuclei significantly increased. However, the frequency of micronuclei did not significantly increase after the continuous treatment with either NKT or KT. Both NKT and KT were determined to be genotoxic in the short-term treatment with or without the S9 mix, but they were determined to be nongenotoxic in continuous treatment.
Conclusion: Our findings suggest that NKT has a stronger genotoxic effect than KT.

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Objectives: The objective of this study was to evaluate factors associated with turnover intention among nurses in small and medium-sized medical institutions.
Methods: A self-administered questionnaire survey was performed in 293 registered nurses, licensed practical nurses, and assistant nurses working full-time in various medical institutions. Multiple linear regression analysis was conducted, with turnover intention as the dependent variable, and nurses’ basic attributes and job satisfaction as independent variables.
Results: As for nurses’ basic attributes, turnover intention was significantly associated with registered nurses, younger nurses and those with low satisfaction with sleep. As for nurses’ job satisfaction, the number of nurses with turnover intention was significantly higher for those with low satisfaction with salary, low satisfaction with welfare, poor implementation of fair salary raise and poor cooperation among nurses.
Conclusion: Turnover intention may be reduced by the enhancement of trust in the organization, giving appropriate advice to young nurses and registered nurses, and developing measures for addressing sleep disorders.

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Objective: Systemic and myelotoxic effects of 2,3,7,8-tetrabromodibenzo-p-dioxin (TBDD) were examined by the single administration of TBDD by gavage to rats.
Methods: Fifteen Wistar rats of both sexes per group received 0, 10, 30, 100 or 300 μg TBDD/kg body weight. Rats surviving to the scheduled necropsy on Days 2, 7 and 36 after TBDD administration were examined for growth rate, organ weight, hematology, histopathology and adipose tissue levels of TBDD.
Results: Three 300 μg/kg-dosed females died on Days 21, 23 and 27, and exhibited a marked decrease in body weight, severe thymic atrophy, decreased bone marrow hematopoiesis and hemorrhage in the subarachnoid space of brain and spinal cord. TBDD-dosed surviving rats exhibited growth retardation, decreased bone marrow hematopoiesis, decreases in red blood cell counts, hemoglobin concentrations, and hematocrit values, an increase in reticulocytes and decreases in platelet counts, white blood cell counts and eosinophils. These signs suggested TBDD myelotoxicity. Splenic extramedullary hematopoiesis was increased in both sexes given TBDD, whereas atrophy of the splenic white pulp occurred only in TBDD-dosed females. Marked decreases in body weights and the size and weight of the thymus, severe thymic atrophy and death in TBDD-dosed females suggested a wasting syndrome. The adipose tissue level of TBDD culminated on Day 7 and decreased to 20–30% of the Day 7 level on Day 36.
Conclusions: The TBDD-induced effects were characterized by a wasting syndrome and myelotoxicity that appeared at the dose levels of 30 μg/kg and higher and caused death in 300 μg/kg-dosed females.

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