Prognostic Factors Analysis of Metastatic Recurrence in Cervical Carcinoma Patients Treated with Definitive Radiotherapy: A Retrospective Study Using Mixture Cure Model.

OBJECTIVES: This study aims to identify prognostic factors associated with metastatic recurrence-free survival of cervical carcinoma (CC) patients treated with radical radiotherapy and assess the cure probability of radical radiotherapy from metastatic recurrence. METHODS: Data were from 446 cervical carcinoma patients with radical radiotherapy for an average follow up of 3.96 years. We applied a mixture cure model to investigate the association between metastatic recurrence and prognostic factors and the association between noncure probability and factors, respectively. A nonparametric test of cure probability under the framework of a mixture cure model was used to examine the significance of cure probability of the definitive radiotherapy treatment. Propensity-score-matched (PSM) pairs were generated to reduce bias in subgroup analysis. RESULTS: Patients in advanced stages (p = 0.005) and those with worse treatment responses in the 3rd month (p = 0.004) had higher metastatic recurrence rates. Nonparametric tests of the cure probability showed that 3-year cure probability from metastatic recurrence was significantly larger than 0, and 5-year cure probability was significantly larger than 0.7 but no larger than 0.8. The empirical cure probability by mixture cure model was 79.2% (95% CI: 78.6-79.9%) for the entire study population, and the overall median metastatic recurrence time for uncured patients (patients susceptible to metastatic recurrence) was 1.60 (95% CI: 1.51-1.69) years. Locally advanced/advanced stage was a risk factor but non-significant against the cure probability (OR = 1.078, p = 0.088). The interaction of age and activity of radioactive source were statistically significant in the incidence model (OR = 0.839, p = 0.025). In subgroup analysis, compared with high activity of radioactive source (HARS), low activity of radioactive source (LARS) significantly contributed to a 16.1% higher cure probability for patients greater than 53 years old, while cure probability was 12.2% lower for the younger patients. CONCLUSIONS: There was statistically significant evidence in the data showing the existence of a large amount of patients cured by the definitive radiotherapy treatment. HARS is a protective factor against metastatic recurrence for uncured patients, and young patients tend to benefit more than the elderly from the HARS treatment.

Characterization of titanium dioxide nanoparticles in confectionary products and estimation of dietary exposure level among the Chinese population.

Titanium dioxide (TiO2) is widely used in the food industry. Recently, European Commission has banned TiO2 as a food additive, raising public concern about its health risk, especially the nanoparticles (NPs) contained therein. This study aimed to reveal the existence of TiO2 NPs in food and further estimate the dietary exposure level among Chinese population by characterizing particle size distribution, determining Ti content and micro-distribution in food products, and calculating food consumption from the China Health and Nutrition Survey (CHNS). The results showed that TiO2 particle size in food additives and chewing gums was 53.5-230.3 nm and 56.8-267.7 nm respectively, where NPs accounted for 34.7% and 55.6% respectively. TiO2 was firstly in situ presented on the surface of confectionary products with hard shells. The content of TiO2 ranged from 3.2 to 3409.3 µg/g product. Besides, the mean dietary intake was 71.31 µg/kgbw/day for TiO2 and 7.75 µg/kgbw/day for TiO2 NPs among Chinese population, affected by people's dietary habits of different regions. Children's exposure levels was the highest due to their love of sweets. More attention should be paid to risk assessment and management of TiO2 NPs for children in China.

Health effects of occupational exposure to printer emissions on workers in China: Cardiopulmonary function change.

Printers emitted nanoparticles (NPs), ozone (O3) and volatile organic chemicals (VOCs) during operation that elicited adverse effects on indoor air quality of the printing room, which may affect the health of exposed workers. The aim of this work was to explore the health effects of occupational exposure to printer emissions on workers, especially cardiovascular and lung function. We sampled particles in the print shop for characterization, including particle size distribution and elemental composition, and measured PM1 number concentrations in print shops and other workplaces. We assessed blood pressure, heart rate and pulmonary function in 53 printing room workers and 54 controls in Beijing, China. Multiple linear regression analysis were used to examine health effects of exposure to printer emissions. The PM1 number concentration in the print shop was more than 2 times that of the control group. Compared with controls, the exposed workers with lower education and income had heavier workload with a median of 7 days per week and 12 h per day on working days, and presented cardiopulmonary function injury with increased the diastolic blood pressure (DBP), systolic blood pressure (SBP), and mean arterial pressure (MAP). The most significant changes of cardiopulmonary function were found in exposed workers with more than 10 years of working age. Multiple linear regression also showed printer emissions exposure was associated with increased SBP and MAP, while decreased lung function indices. This study found changes in the cardiopulmonary function of staff members exposed to printer emissions, which prompted the necessity and urgency of improving the environment of printing rooms and protecting the health of exposed workers.