Objective To quantitatively assess the association of short-term exposure to polycyclic aromatic hydrocarbons (PAHs) in ambient fine particulate matter (PM2.5) with residents mortality. Methods A time-stratified case-crossover study was conducted from 2020 to 2022 among 10606 non-accidental residents by using the Guangzhou Cause of Death Surveillance System in Conghua District, Guangzhou. Exposure levels of PAHs in PM_2.5 and meteorological data during the study period were obtained from the Center for Disease Control and Prevention in Conghua District and the China Meteorological Administration Land Data Assimilation System (CLDAS-V2.0), respectively. Conditional Poisson regression model was used to estimate the exposure-response association between PAHs and the mortality risk. Results Fluoranthene, chrysene, benzo[k]fluoranthene, benzo[a]pyrene, and indeno[1,2,3-cd]pyrene were significantly associated with an increased risk of mortality. For every one interquartile range increase in exposure levels, the non-accidental mortality risks increased by 8.33% (95% CI: 1.80%, 15.27%), 4.67% (95% CI: 1.86%, 7.57%), 6.07% (95% CI: 2.08%, 10.21%), 4.62% (95% CI: 1.85%, 7.47%), and 4.70% (95% CI: 0.53%, 9.03%), respectively. The estimated non accidental deaths attributable to exposure to fluoranthene, chrysene, benzo[k]fluorine, benzo[a]pyrene and indine[1,2,3-cd]pyrene were 5.91%, 6.08%, 6.51%, 6.46%, and 4.21%, respectively. Conclusions Short-term exposure to PAHs in PM_2.5, including fluoranthene, chrysene, benzo[k]fluoranthene, benzo[a]pyrene and indine[1,2,3-cd]pyrene, was significantly associated with an increased risk of mortality among residents.

Positron emission tomography (PET)/CT plays an important role in the diagnosis of bone metastasis from lung cancer,and can reflect the pathophysiological and morphological changes in lesion of bone metastasis.The sensitivity,specificity and the overall accuracy of PET-CT for the diagnosis of bone metastasis in patients with lung cancer are higher than those of routine methods such as X-ray,CT scan,MRI and SPECT/CT.

After chemoradiation therapy, tumor tissue metabolism changes earlier than its shape in advanced non-small cell lung cancr (NSCLC). Therefore, Positron emission tomography-computed tomography (PET-CT) can early assess the therapeutic efficacy and prognosis. But PET-CT might bring up some false negative or false positive outcome, while combined with the tumor markers, more accurate assessments of therapeutic efficiency and prognosis could be made for advanced(NSCLC).