The increases in relative mRNA expressions of inflammatory cytokines and chemokines in splenic macrophages from rats exposed to multi-walled carbon nanotubes by whole-body inhalation for 13 weeks.

BACKGROUND: The toxicity of multi-walled carbon nanotubes (MWCNT) may be related to the immune system. The objective of this study was to obtain information for immunotoxic mechanisms of MWCNT in situ. METHODS: Using whole-body inhalation, male and female rats were exposed to 0, 0.2, 1 or 5 mg MWCNT/m³ for 13 weeks. Thereafter, spleens were recovered from the rats. Real-time PCR was done to assess expression of TNFα, IL-1ß, IL-6, IL-10, MCP-1 and MIP-1α mRNA in the splenic macrophages; splenic T-lymphocytes were examined for IL-2 and TGF-ß1 mRNA expression. RESULTS: The relative expression of IL-1ß mRNA in the cells from female rats exposed to 5 mg MWCNT/m³ was significantly higher than that in control cells. For IL-6 and IL-10, cells from rats in the 0.2 and 5 mg MWCNT/m³ had significantly higher mRNA expressions than did cells from controls. Expression of IL-1ß, IL-6 and TNFα genes in cells from males in all exposure groups were higher than in control cells. Expression of MIP-1α in the cells from female 5-mg group was significantly higher than that in cells in the control. Only IL-2 was expression reduced, i.e. cells from male and female rats in all MWCNT groups had significantly lower mRNA expressions than control cells. CONCLUSIONS: Systemic inflammation would likely occur in rats (or other hosts) exposed to MWCNT via inhalation due to increases in the expression of inflammatory cytokines in splenic macrophages. Moreover, decreases in IL-2 expression in T-lymphocytes may be critical to the potential reductions in anti-tumor responses in MWCNT-exposed hosts.

[The history of compensation system for workers with pneumoconiosis-related lung cancer].

OBJECTIVE: To review the historical aspects of compensation system for workers with pneumoconiosis who developed lung cancer. METHODS: Materials and papers published on the compensation system as discussed in administrative meetings were utilized. RESULTS: Legal claims for compensation for lung cancer among individuals with pneumoconiosis increased during the period of rapid economic growth in Japan. A possible causal relationship between pneumoconiosis and lung cancer in workers has been discussed by committees of specialists. The Expert Committee on Pneumoconiosis and Lung Cancer in 1978 did not find a causal relationship between them. However, a survey of physicians specializing in pneumoconiosis revealed medical disadvantages among individuals diagnosed with pneumoconiosis who developed lung cancer. The Ministry of Labour announced the risk of work-related lung cancer in patients with advanced pneumoconiosis (class IV or equivalent severity). Since then, numerous lung cancer patients with pneumoconiosis have been adjudicated. In 1997, the International Agency for Research on Cancer (IARC) re-evaluated the carcinogenicity of silica and declared it to be a Group I carcinogen in humans. The Expert Committee on Compensation of Lung Cancer Cases Developing from Pneumoconiosis discussed the IARC evaluation but did not accept this classification. However, the Committee of Occupational Exposure Limits in the Japan Society of Occupational Health upheld the IARC evaluation of silica as a Group I carcinogen. Because the Expert Committee of Medical Disadvantage of Lung Cancer Patients with Pneumoconiosis accepted the increased risk of lung cancer in patients with class III or equivalent severity pneumoconiosis, the Ministry of Labour announced worker compensation for such patients. The Expert Committee of Health Control of Pneumoconiosis Complicated with Lung Cancer reported in 2002 that a meta-analysis revealed no increased risk of lung cancer among workers exposed to crystalline silica; however, there was an increased risk of lung cancer in patients with pneumoconiosis. The Ministry of Labour has added lung cancer to the list of complications from pneumoconiosis and, if necessary, regular medical checkups for lung cancer. After Leaving dust work, the Health Care System provides for workers who are diagnosed With class II or higher pneumoconiosis. Therefore, if an individual with pneumoconiosis develops class II or higher lung cancer, that individual becomes eligible for workers' compensation. CONCLUSIONS: The conclusion of the Expert Committee in 2002 and the decision of the Ministry of Labour to add lung cancer to its list of complications of pneumoconiosis are evaluated to be appropriate.

Nursing students' learning motivation toward technical knowledge and their ethics regarding patients' rights.

Nursing students must develop their abilities to provide appropriate nursing services. They need to acquire the level of nursing knowledge to pass the national examination according to Japanese law. Moreover, even if the awareness of the rights of people who receive nursing services increases, students must not have a sense of resistance toward those rights. Therefore, we investigated the factors associated with students' motivation to pass their examination and such a sense of resistance. We produced items related to reasons students wanted to become registered nurses with reference to job satisfaction and their learning environment (e.g., teachers' manners and school events unrelated to the examination). There were 3,417 female nursing students analyzed in 29 vocational schools that allow graduation after a 3-year study period (average age, 21.93 years [standard deviation, 5.44]). Older and third-year students had a stronger motivation to pass the examination and a weaker sense of resistance to people's rights compared with younger and first- to second-year students. Students who answered a "Lack of enthusiasm for becoming a registered nurse" had a weakened motivation and a strengthened sense of resistance. Factors enhancing students' motivation to pass their examination were "Professional commitment," "Desire for companionship," and "School events unrelated to the national examination." Factors strengthening students' sense of resistance to people's rights were "Living stability" and "Social appraisal." Teachers must develop methods to teach ethics so that their students respect the rights of people who receive nursing services and to ensure that they acquire the necessary nursing knowledge.

Five reasons for the lack of nursing students' motivation to learn public health.

Prevention is better than cure. Public health plays an important role in promoting prevent medicine. To obtain the abilities to provide appropriate nursing services, learning public health is necessary for students who want to become registered nurses. When teachers teach public health to nursing students, it is important to motivate them to learn it. Therefore, we investigated the reasons for the lack of motivation to learn public health by conducting a questionnaire survey. The subjects were female nursing students in 29 vocational schools in Kanagawa and Chiba prefectures of Japan that allow graduation after a 3-year study period. We asked the students whether or not they had completed the subject of public health and analyzed those students who answered affirmatively. We analyzed 1,553 respondents whose average age was 22.6 ± 5.2 years (range, 18 to 45). Using factor analysis, we discovered the 5 reasons that lead to the lack of nursing students' motivation to learn public health: "Difficulties acquiring knowledge of public health," "Inappropriate attitudes of public health teachers," "Thinking lightly about the national examination in the field of public health," "Lack of understanding the importance of learning public health," and "Future plans that do not specialize in public health." Using multiple linear regression analysis, these 5 reasons were significant predictors for the lack of students' motivation. Older students also had significantly less motivation to learn public health than did younger students. When teachers instruct their students, they should teach public health better with the present knowledge.

Maternal and paternal family history of type 2 diabetes differently influence lipid parameters in young nondiabetic Japanese women.

OBJECTIVES: We assessed the association of family history of type 2 diabetes (T2D) with parameters used for health checkups in young Japanese women. METHODS: The subjects were 497 nondiabetic women aged 19-39 years. Among them, the mothers of 34 subjects and fathers of 50 had T2D (MD group and PD group, respectively). The subjects were assessed for levels of total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and triglyceride (TG). RESULTS: TC and LDL-C level showed a tendency to increase in the MD group compared with subjects without family history of T2D. LDL-C/HDL-C ratio ≥2.14 was found in 32.4 and 18.0 % of subjects in the MD and PD groups, respectively. When adjusted for differences in age, body mass index, smoking status, and drinking habits, the MD group was found to have a higher risk of abnormal TC and LDL-C levels than the PD group. LDL-C/HDL-C ratio was independently associated with maternal family history but not with paternal family history (odds ratio 3.44 [99 % confidence interval 1.11-10.6] and 1.21 [0.38-3.89], respectively). There was no association between TG/HDL-C ratio and family history type of T2D. CONCLUSIONS: Maternal family history of T2D had a more pronounced effect on the lipid parameters generally evaluated during health checkups than did paternal family history of T2D. Therefore, we recommend systematic screening for early detection and appropriate healthcare guidance for Japanese women, particularly those with maternal family history of T2D.

Abnormality of risk factors for atherosclerotic disease among young Japanese aged 19-39 years old: an evaluation of health checkup data.

OBJECTIVES: Japanese public health policies on the prevention of atherosclerotic diseases have focused on controlling obesity. The aim of this study was to assess the prevalence of abnormality in risk factors for atherosclerotic disease among young Japanese classified according to body mass index (BMI). METHODS: Data were obtained from 359 men (mean age 32 ± 5 years) and 1,108 women (mean age 33 ± 4 years) between 2005 and 2010. Abnormal levels of aspartate aminotransferase, alanine aminotransferase, and/or gamma-glutamyltranspeptidase were considered to indicate liver dysfunction, and abnormal levels of low-density lipoprotein-cholesterol, high-density lipoprotein-cholesterol, and/or triglycerides were considered to indicate dyslipidemia. The cutoff points for high blood pressure (HBP) and hyperglycemia were set as a reference in the high-normal range. RESULTS: No significant difference was observed in both sexes in all items among each year. In men, HBP (12.9 %), liver dysfunction (33.9 %), dyslipidemia (29.9 %), and hyperglycemia (2.7 %) were observed in the normal BMI group (18.5 < BMI ≤ 25 kg/m(2)). In women, these abnormalities were observed in both the normal BMI group and lean group. CONCLUSIONS: Asymptomatic abnormalities, particularly liver dysfunction and dyslipidemia, were observed in a substantial percentage of subjects without obesity. Therefore, we recommend that the comprehensive public health policy should be directed at all individuals, including the non-obese group, for the early prevention/detection against atherosclerotic diseases.

Awareness and behavior of oncologists and support measures in medical institutions related to ongoing employment of cancer patients in Japan.

OBJECTIVE: Improved outcomes of cancer treatment allow patients to undergo treatment while working. However, support from oncologists and medical institutions is essential for patients to continue working. This study aimed to clarify oncologists' awareness and behavior regarding patients who work during treatment, support in medical institutions and their association. METHODS: A questionnaire was mailed to all 453 diplomates and faculty of the subspecialty board of medical oncology in the Japanese Society of Medical Oncology and all 1016 surgeons certified by the Japanese Board of Cancer Therapy living in the Kanto area. The questionnaire assessed demographics, oncologist awareness and behavior regarding patient employment and support measures at their medical institutions. Logistic regression analysis was used to examine the association of awareness and behavior of oncologists with support measures at their institutions. RESULTS: A total of 668 individuals participated. The overall response rate was 45.5%. Only 53.6% of respondents advised patients to tell their supervisors about prospects for treatment and ask for understanding. For medical institutions, 28.8% had a nurse-involved counseling program and adjustments in radiation therapy (28.0%) and chemotherapy (41.9%) schedules to accommodate patients' work. There was a significant correlation between awareness and behavior of oncologists and medical institutions' measures to support employed cancer patients. CONCLUSIONS: There is room for improvement in awareness and behavior of oncologists and support in medical institutions for cancer patients continuing to work. Oncologists could support working patients by exerting influence on their medical institutions. Conversely, proactive development of support measures by medical institutions could alter the awareness and behavior of oncologists.

Japanese professional nurses spend unnecessarily long time doing nursing assistants' tasks.

In environments in which professional nurses do simple tasks, e.g., laundry, cleaning, and waste disposal, they cannot concentrate on technical jobs by utilizing their expertise to its fullest benefit. Particularly, in Japan, the nursing shortage is a serious problem. If professional nurses take their time to do any of these simple tasks, the tasks should be preferentially allocated to nursing assistants. Because there has been no descriptive study to investigate the amount of time Japanese professional nurses spent doing such simple tasks during their working time, their actual conditions remain unclear. Professional nurses recorded their total working time and the time they spent doing such simple tasks during the week of the survey period. The time an individual respondent spent doing one or more simple tasks during that week was summed up, as was their working time. Subsequently, the percentage of the summed time he or she spent doing any of those tasks in his or her summed working time was calculated. A total of 1,086 respondents in 19 hospitals that had 87 to 376 beds were analyzed (response rate: 53.3%). The average time (SD) that respondents spent doing those simple tasks and their total working time were 2.24 (3.35) hours and 37.48 (10.88) hours, respectively. The average percentage (SD) of the time they spent doing the simple tasks in their working time was 6.00% (8.39). Hospital administrators must decrease this percentage. Proper working environments in which professional nurses can concentrate more on their technical jobs must be created.

Association between asymptomatic hyperuricemia and new-onset chronic kidney disease in Japanese male workers: a long-term retrospective cohort study.

BACKGROUND: Hyperuricemia is prevalent in patients with chronic kidney disease (CKD). We explored the hypothesis that asymptomatic hyperuricemia may be associated with new-onset CKD. METHODS: The participants were all male factory workers in Kanagawa, Japan (n = 1,285). All were over 40 years of age and had undergone annual health examinations from 1990 to 2007. Individuals with a history of gouty attacks were excluded from the study. A retrospective cohort study was conducted by following the estimated glomerular filtration rate (eGFR) for each participant over a maximum period of 18 years. The endpoint was new-onset CKD defined as eGFR < 60 mL/min/1.73 m2. The associations between new-onset CKD and the presence of hyperuricemia, low serum high-density lipoprotein cholesterol, hypertension, diabetes, and obesity were analyzed. RESULTS: The mean (± standard deviation) follow-up period was 95.2 (± 66.7) months, and new-onset CKD was observed in 100 participants (7.8%) during this follow-up. Cox proportional hazards model revealed that the hazard ratio of new-onset CKD due to hyperuricemia, low serum high-density lipoprotein cholesterol, hypertension and obesity were 3.99 (95% confidence interval: 2.59-6.15), 1.69 (1.00-2.86), 2.00 (1.29-3.11) and 1.35 (0.87-2.10), respectively. Concerning hyperuricemia, low serum high-density lipoprotein cholesterol, hypertension and obesity, the log-rank tests showed P values of < 0.01, 0.01, < 0.01 and < 0.01, respectively. CONCLUSION: The results of this study suggest that asymptomatic hyperuricemia is a predictive factor for new-onset CKD for Japanese male workers.

Work-family conflict and prolonged fatigue among Japanese married male physicians.

PURPOSE: Fatigue experienced by physicians may not only endanger their own health but may also affect the safety of patients. Such fatigue may be associated with the work environment and personal factors such as work-family conflict (WFC). This study aimed to determine the association between WFC and prolonged fatigue among Japanese married male physicians. METHODS: Physicians who graduated from a Japanese medical school answered a mailed anonymous self-report questionnaire. For assessment of WFC and prolonged fatigue, the Japanese versions of the WFC scale and the Checklist of Individual Strength questionnaire (CIS) were used. Prolonged fatigue was defined as the upper quartile of total CIS scores. The WFC scale comprises six dimensions. Total scores were divided into tertiles: low, intermediate, and high levels of WFC. A multiple logistic regression analysis was performed to examine the association between WFC and prolonged fatigue. RESULTS: A total of 540 male physicians answered the questionnaire, and the data of 444 married male physicians were analyzed. The data were then adjusted for age and work condition factors. Prolonged fatigue was significantly associated with high strain-based work interference with family (WIF; corrected odds ratio, 5.56; 95% confidence interval, 2.55-12.1), intermediate strain-based WIF (2.53, 1.25-5.10), high time-based family interference with work (FIW; 1.92, 1.08-3.40), and there was a weak association with high strain-based FIW (1.93, 0.98-3.83). CONCLUSIONS: Employers should take measures to improve working conditions in hospitals, and give physicians the opportunity to learn how to cope with WFC. These measures could ultimately help prevent prolonged fatigue.

Work motivation for Japanese nursing assistants in small- to medium-sized hospitals.

Nursing assistants can work without a professional certification to help registered nurses and licensed practical nurses. Nursing assistants engage in various tasks, e.g., washing laundry, cleaning up, and clerk tasks regarding nursing. Enhancing work motivation among nursing assistants is essential for every hospital, because when nursing assistants do their jobs well, it allows registered nurses and licensed practical nurses to complete their own specialized jobs. We examined the predictors significantly associated with nursing assistants' work motivation. For those predictors, we produced items to examine job satisfaction. Those items are classified into intrinsic and extrinsic facets. The subjects for this study were Japanese nursing assistants working in 26 hospitals with 62-376 beds (4 public and 22 private hospitals). A total of 516 nursing assistants were analyzed, with the average age and standard deviation of 42.7 ± 12.9 years; the age of 456 female subjects was 43.8 ± 12.7 years and that of 60 male subjects was 34.3 ± 11.0 years. Our results show that "work motivation" is significantly associated with "free time to do one's own things," "nursing assistants as important partners on the job," "feeling helpful to patients," "participating in decision making," and "job-skill improvement." Free time to do one's own things is an extrinsic item. Hospital administrators must monitor the workload and their quality of life among nursing assistants. All the other significant items are intrinsic. Nursing assistants are not only motivated by money. They highly value the intrinsic nature and experience of their jobs.

Building medical ethics education to improve Japanese medical students' attitudes toward respecting patients' rights.

In medical education, it is important for medical students to develop their ethics to respect patients' rights. Some physicians might make light of patients' rights, because the increased awareness of such rights might make it more difficult for them to conduct medical practice. In the present study, predictors significantly associated with "a sense of resistance to patients' rights" were examined using anonymous self-administered questionnaires. For these predictors, we produced original items with reference to the concept of ethical development and the teachings of Mencius. The subjects were medical students at the Kitasato University School of Medicine, a private university in Japan. A total of 518 students were analyzed (response rate, 78.4%). The average age of enrolled subjects was 22.5 ± 2.7 years (average age ± standard deviation). The average age of 308 male subjects was 22.7 ± 2.8 years, while that of 210 female subjects was 22.1 ± 2.5 years. The item, "Excessive measures to pass the national examination for medical practitioners," was significantly associated with "a sense of resistance to patients' rights." However, other items, including basic attributes such as age and gender, were not significant predictors. If students spent their school time only focusing on the national examination, they would lose the opportunity to receive the ethical education that would allow them to respect patients' rights. That ethical development cannot easily be evaluated with written exams. Thus, along with the acquisition of medical knowledge, educational programs to promote medical students' ethics should be developed.

Cytotoxicity and solubility evaluation of two types of whiskers by cell magnetometry.

OBJECTIVES: We investigated two types of whiskers, an antimony-containing tin-oxide-coated aluminum borate whisker (CABW) and an aluminum borate whisker (ABW), which are asbestos substitutes, in order to evaluate the safety of these fibers. METHODS: The cytotoxicity and solubility of CABW and ABW were evaluated by cell magnetometry, LDH assay and solubility test. RESULTS: ABW was found to be cytotoxic by cell magnetometry and slightly less soluble than CABW. In addition, it was found that the solubility of both fibers was intermediate between that of chrysotile and rock wool, as compared to our previous test results. Regarding the LDH assay, no significant difference was found among the fibers tested. These findings suggested that CABW, the surface of which is coated with antimony-containing tin oxide, had lower cytotoxicity and slightly higher solubility than ABW. CONCLUSIONS: This study was only a short-term cytotoxicity and solubility study. Therefore, further safety assessment should be carried out in long-term experiments to examine the half-life of these fibers and monitor the potential development of lung carcinoma or mesothelioma after intratracheal instillation of these fibers in rats.

Oxidative stress in mature rat testis and its developmental changes.

Active oxygen causes various problems including male infertility through the oxidation of DNA, proteins, and lipids. In the present study, we examined the immunohistochemical localization of molecules involved in oxidative stress including 8-hydroxy-2-deoxyguanosine (8-OHdG), superoxide dismutase (SOD), and protein disulfide isomerase (PDI) in mature and developing rat testes. In mature rat testes, 8-OHdG was detected in leptotene, zygotene, and early pachytene spermatocytes, while its expression was weak in late pachytene stage spermatocytes. On the other hand, SOD was detected in late pachytene spermatocytes but not in early pachytene and former spermatocytes, suggesting the efficient removal of active oxygen by SOD in late pachytene spermatocytes. In developing rat testes, 8-OHdG expression peaked at 4 weeks when spermatocytes started to differentiate to the late pachytene stage, while SOD started to be expressed at 4 weeks after birth. These findings suggest that the defense system against oxidative stress by SOD is developed in late pachytene stage spermatocytes at 4 weeks after birth. The present findings aid our understanding of the defensive mechanism against oxidative stress in developing and mature testes.

Enhancing work motivation for Japanese female nurses in small to medium-sized private hospitals by analyzing job satisfaction.

Proper work environments are important for nurses to feel motivated. We examined the associations between work motivation and job satisfaction among Japanese nurses to improve their motivation. In Japan, relatively small and medium-sized private hospitals play a central role in the healthcare industry. In the present study, the subjects were nurses working in 23 small and medium-sized private hospitals that had 65 to 326 beds. We analyzed 1,116 registered and licensed practical female nurses (average age, 38.3 years; standard deviation, 11.3 years). Many nurses with their specialized nursing skills dedicate themselves to patient care. However, many of these nurses may not be interested in contributing to their hospitals. Nurses may have different opinions regarding dedication to patient care and contribution to their hospitals. Therefore, concerning work motivation, we produced these two different items, "Nurses' dedication to patients" and "Nurses' contribution to their hospitals." We also produced our own original new job satisfaction questionnaire. We found 7 facets of job satisfaction: "Work as specialists," "Workplace safety," "Relationships with superiors," "Work-life balance," "Relationships among nurses," "Communications with physicians," and "Salary." Multiple linear regression analyses show that both "Nurses' dedication to patients" and "Nurses' contribution to their hospitals" were significantly associated with "Work as specialists." Nurses feel their jobs of protecting people's lives and health are valuable. They do not feel motivated only by money. They value the intrinsic nature of their jobs. Creating proper work environments is important for nurses to be able to work as specialists.

Higher toxicity of dibutyltin and poly-L-lactide with a large amount of tin but lower toxicity of poly-L-lactide of synthetic artificial dura mater exhibited on murine astrocyte cell line.

Neurotoxicities of dibutyltin (DBT), tin(II) octylate (OT), poly-L-lactides (PLLA, molecular weight [MW]=5000, PLLA 5000), PLLA without tin (MW=3000, PLLA 3000), PLLA with a large amount (590 ppm) of tin (S3), poly(glycolic acid-co-epsilon-caprolactone) oligomer (MW=6200, PGC oligomer), and poly(L-lactic acid-co-glycolic acid-co-epsilon-caprolactone) oligomer (MW=6400, PLGC oligomer) related to artificial dura mater were examined using the murine astrocyte cell line, CRL-2534. The indices were cell viability, glutamate concentration in the cell supernatant, and cell proliferation. Lower cell viability was observed among cells exposed to 0.5 microM DBT or 10 microg/ml of S3. There were no differences in cell viability of astrocytes exposed to OT, PLLA 5000, PLLA 3000, PGC oligomer, or PLGC oligomer. Mean glutamate concentration in the supernatant of cells exposed to 0.25 muM DBT was higher than that of the control after 2 h incubation. Lower mean concentration of glutamate in the supernatant of cells exposed to 5 microg/ml of S3 was observed after 2 h incubation. Cells exposed to 50 microg/ml of PGC oligomer had a higher mean concentration of glutamate in the supernatant. OT only inhibited cell proliferation at 100 microM. Proliferation of cells exposed to 0.25 microM or 0.5 microM DBT was inhibited, as was that of cells exposed to 100 microM OT, 50 microg/ml PLLA 5000, 50 microg/ml PLLA 3000, and 5 microg/ml S3, 5 d and 7 d after exposure. Although DBT does not reach levels that induced neurotoxicity in artificial dura mater, these results suggest that DBT is neurotoxic and PLLA toxicity increases with the increase in tin concentration.

Magnetometric evaluation of toxicities of chemicals to the lungs and cells.

Because the lungs are exposed to airborne hazardous materials, alveolar macrophages (AMs) play a major role in defending against the exposure to various noxious chemical substances. In this study, we reviewed magnetometric investigations of the effects of various chemicals on the lungs and AMs. Magnetometry, using magnetite as an indicator, was used to evaluate the effects of certain chemicals on the lung and AMs. A rapid decrease of the remanent magnetic field after the cessation of external magnetization, a phenomenon called relaxation, was impaired when the lungs and macrophages were exposed to toxic substances. The delayed in vivo relaxation observed in the lungs exposed to magnetite and gallium arsenide was almost identical to the in vitro relaxation observed in the AMs exposed to the same materials. Delayed relaxation was observed in the AMs exposed to silica dust; various fibers, such as chrysotile and some man-made mineral fibers; and toxic arsenic and cadmium compounds. The extracellular release of lactate dehydrogenase activity was found in the AMs exposed to the chemicals. Relaxation is attributed to the cytoskeleton-driven rotation of phagosomes containing magnetite. While the exact mechanism of delayed relaxation due to exposure to harmful chemicals remains to be clarified, cell magnetometry appears to be useful for the safety screening of chemical substances.

Maintenance of influenza virus infectivity on the surfaces of personal protective equipment and clothing used in healthcare settings.

OBJECTIVES: The maintenance of infectivity of influenza viruses on the surfaces of personal protective equipment and clothing is an important factor in terms of controlling viral cross-infection in the environment and preventing contact infection. The aim of this study was to determine if laboratory-grown influenza A (H1N1) virus maintained infectivity on the surfaces of personal protective equipment and clothing used in healthcare settings. METHODS: Influenza A virus (0.5 mL) was deposited on the surface of a rubber glove, an N95 particulate respirator, a surgical mask made of non-woven fabric, a gown made of Dupont Tyvek, a coated wooden desk, and stainless steel. Each sample was left for 1, 8, and 24 h, and hemagglutination (HA) and 50% tissue culture infective dose (TCID(50))/mL were measured. RESULTS: The HA titer of this influenza A virus did not decrease in any of the materials tested even after 24 h. The infectivity of influenza A virus measured by TCID(50) was maintained for 8 h on the surface of all materials, with the exception of the rubber glove for which virus infectivity was maintained for 24 h. CONCLUSIONS: Our results indicate that the replacement/renewal of personal protective equipment and clothing by healthcare professionals in cases of exposure to secretions and droplets containing viruses spread by patients is an appropriate procedure to prevent cross-infection.

[Analysis of occupational health activities through classifying reports from medical facilities in Japan].

OBJECTIVES: The objectives of this study were to analyze current trends in occupational health activities by classifying reports from medical facilities in Japan. METHODS: Reports of current workplace-level occupational health activities from medical activities that were collected by the Japan Medical Association Occupational Health Committee were used for the study. Of 5,000 questionnaire forms sent to medical facilities, 1,920 responses were returned. The freely described reports on ongoing occupational health activities contained in these responses were classified according to each of the following aspects of reported activities: 1) details of occupational health activities including main actors in workplace-level actions; and 2) approaches taken for occupational safety and health. The classification of the reports was implemented by a working group comprising selected occupational health practitioners and researchers. RESULTS: Among 1,920 survey responses, 581 valid texts were analyzed. Altogether, 1,044 occupational health activities currently undertaken by the facilities were extracted. The reported activities that were classified according to details of occupational health activities mainly comprised "Measures for preventing overwork, labor management, and work-style reform" (35.7%), "Measures for improving mental health" (21.0%), and "Review of occupational safety and health management systems" (19.3%). Medical facilities implementing "Measures for mental health" alongside "Measures for preventing overwork, labor management, and work-style reform" were reported in 13.2% of the responding medical facilities. "Occupational health professionals or safety and health management staff" (71.7%) were the most frequent main actors of these activities, followed by "Members of the workplace" (18.4%) and "Outsourced experts" (2.4%). "Comprehensive safety and health management" (42.0%) was the most common approach taken for occupational safety and health, followed by "Management focusing on topics" (23.8%) and "Case management" (16.5%). Most of these activities focused on primary prevention aimed at labor management including prevention of overwork, work-style reform, and mental health promotion. Another key trend could be "Teamwork among occupational safety and health staff, workers, and employers at respective workplaces as well as outsourced experts." DISCUSSION: Several key trends were extracted from current occupational health activities at medical facilities. In most cases, these measures were implemented simultaneously. This suggests the importance of combining primary prevention measures for mental health with measures for labor management including prevention of overwork. These activities reflect emerging trends that incorporate teamwork between experts, workers, and employers, and provide new perspectives on workplace-level occupational safety and health activities.

Cytotoxicity study of rock wool by cell magnetometric evaluation.

The cytotoxicity of rock wool (RW), an asbestos substitute, was evaluated by cell magnetometry. Alveolar macrophages were isolated from male Fisher rats. Following addition of triiron tetraoxide (Fe(3)O(4)) to macrophages, RW was added. Then, the remnant magnetic field strength was measured for 20min after magnetization by an external field. Relaxation, an indicator of decay of cytotoxicity, was observed by cell magnetometry immediately postmagnetization in the group to which RW was added. In general, materials phagocytosed by macrophages are ingested into phagosomes and digested while migrating. This migration of phagosomes occurs by polymerization and depolymerization of the cytoskeleton. As a result of evaluation, relaxation was not delayed by addition of RW, since RW caused no effect on the cytoskeleton. It was suggested that RW has no cytotoxicity as evaluated by cell magnetometry.