Exposure to PM2.5 and Lung Function Growth in Pre- and Early-Adolescent Schoolchildren: A Longitudinal Study Involving Repeated Lung Function Measurements in Japan.

Rationale: Epidemiological evidence indicates that ambient exposure to particulate matter ⩽2.5 µm in aerodynamic diameter (PM2.5) has adverse effects on lung function growth in children, but it is not actually clear whether exposure to low-level PM2.5 results in long-term decrements in lung function growth in pre- to early-adolescent schoolchildren. Objectives: To examine long-term effects of PM2.5 within the 4-year average concentration range of 10-19 µg/m3 on lung function growth with repeated measurements of lung function tests. Methods: Longitudinal analysis of 6,233 lung function measurements in 1,466 participants aged 8-12 years from 16 school communities in 10 cities around Japan, covering a broad area of the country to represent concentration ranges of PM2.5, was done with a multilevel linear regression model. Forced expiratory volume in 1 second, forced vital capacity (FVC), and maximal expiratory flow at 50% of FVC were used as lung function indicators to examine the effects of 10-µg/m3 increases in the PM2.5 concentration on relative growth per each 10-cm increase in height. Results: The overall annual mean PM2.5 level was 13.5 µg/m3 (range, 10.4-19.0 µg/m3). We found no association between any of the lung function growth indicators and increases in PM2.5 levels in children of either sex, even after controlling for potential confounders. Analysis with two-pollutant models with O3 or NO2 did not change the null results. Conclusions: This nationwide longitudinal study suggests that concurrent, long-term exposure to PM2.5 at concentrations ranging from 10.4 to 19.0 µg/m3 has little effect on lung function growth in preadolescent boys or pre- to early-adolescent girls.

Wide-spread ignorance on the treatment of subcutaneous malignant tumors; a questionnaire-based study.

BACKGROUND: Subcutaneous malignant tumors are often treated by non-specialized clinicians in musculoskeletal oncology. While the resection of subcutaneous tumors appears technically feasible, unplanned resection of malignant tumors can result in a devastating clinical outcome. The aim of this study was to evaluate the potential estrangement in the awareness of and the treatment strategy for the patients with subcutaneous soft tissue tumors between musculoskeletal oncologists and non-specialized clinicians. METHODS: A questionnaire probing the clinical assessment of subcutaneous tumors was sent to orthopedic surgeons, dermatologists, plastic surgeons, and general surgeons. Results of the questionnaire were statistically analyzed. RESULTS: One hundred sixteen clinicians out of 150 responded to the questionnaire; the response rate was 77.3%. Among those, 46 clinicians had treated subcutaneous tumors. Thirty-nine of these 46 clinicians (27 musculoskeletal oncologists and 12 non-specialized clinicians) preoperatively performed enhanced MRI for diagnostic evaluation. Preoperative incisional biopsy to confirm the pathological diagnosis was performed by 36 of the 46 clinicians (29 musculoskeletal oncologists and seven non-specialized clinicians). These results indicate that musculoskeletal oncologists perform preoperative enhanced MRI (P = 0.08) and biopsy (P < 0.01) more frequently than non-specialized clinicians. The recognition rate of 'myxofibrosarcoma' was 60.8% among clinicians with an experience with sarcoma treatment (25 musculoskeletal oncologists and three non-specialized clinicians). The recognition rate of 'myxofibrosarcoma' between musculoskeletal oncologists and non-specialized clinicians was statistically significant (P < 0.01). CONCLUSIONS: Preoperative evaluations for subcutaneous tumors are more often inappropriate in non-specialized clinicians than those who are. Therefore, it will be mandatory to raise the awareness of this condition to improve the clinical outcome of patients with subcutaneous tumors.