Evolutionary game analysis of indoor radon mitigation with local government involvement.

Radon is the second leading risk factor for lung cancer after smoking. As a public policy, radon mitigation not only involves radon control technology or its cost-benefit analysis, but also includes the decision-making process of local governments. In this study, the evolutionary game theory was used to analyse the interaction between local governments and residents based on the subsidy of the central government. Considering the practical data in China, factors influencing the behaviour of local governments and residents were discussed using numerical simulations. The results indicated that radon mitigation is a fully government-promoted action; thus, its implementation largely depends on the subsidy of the central government and the share of radon control costs borne by the local government. The financial burden for both local governments and residents is a more important determinant than long-term health effects. The relatively poor local economic situation could limit the implementation of radon control. There would be a public policy paradox wherein cities or regions with higher radon risk would have lower willingness for radon control, mainly due to the significantly higher costs of radon control. This work provides reference data for decision-making to implement radon control and is expected to offer some suggestions for local governments.

Development and calibration of a modifiable passive sampler for monitoring atmospheric tritiated water vapor in different environments.

Anthropogenic release of tritium from nuclear facilities is expected to increase significantly in the coming decades, which may cause radiation exposure to humans through the contamination of water and food chains. It is necessary and urgent to acquire detailed information about tritium in various environments for studying its behavior and assessing the potential radiation risk. In the atmosphere, although the passive sampling technique provides a low-cost and convenient way to characterize the dynamics of tritiated water vapor (HTO), a single, simple sampler configuration makes it difficult to collect sufficient and representative samples within the expected period from different environments. In this study, we systematically studied the impacts of sampler configurations on sampling performance and proposed a modifiable sampler design by scaling sampler geometry and adjusting absorbent to achieve different monitoring demands. The samplers were subsequently deployed at five sites in China and Germany for the field calibration and the measured results exhibited a good agreement between the adsorption process obtained in sites corrected with diffusion coefficient and the one calibrated in Shanghai. This suggests the feasibility of predicting sampling performance in the field based on known data. Finally, we developed a strategy for sampler modification and selection in different environments and demonstrated that using easily obtainable environmental data, our sampler can be optimized for any area without any time-consuming preliminary experiments. This work provides a scientific basis for establishing high-resolution atmospheric HTO database and expands the conventional empirical sampler design paradigm by demonstrating the feasibility of using quantitative indices for sampler performance customization.

Reanalysis of residential radon surveys in China from 1980 to 2019.

A study on the published historic data of the residential radon concentration was carried out in order to provide a systematic retrospect and the confluent analysis of the investigations from 1980 to 2019 in China. A new database was established by collecting the results of nearly all radon surveys reported in China. A total of 129 surveys on residential radon, covering 147 cities with the sampling size of 72,295 were collected into the data pool for secondary analysis. The results from different decades confirmed the rapid increase trend of residential radon concentration in China. The geographical coverage, the sampling density and the geographic distribution of sampling sites of these surveys were discussed. The analysis on the local data sequences indicated the average increasing rate of residential radon concentration for 28 Chinese cities was estimated to be 0.80 Bq·m-3·a-1 in last 40 years. The results in this study provided the overall expression of the radon investigations in China and were expected to be benefit to the radon-related studies in the future.

Benzo[a]pyrene promotes progression in tongue squamous cell carcinoma.

OBJECTIVES: Benzo[a]pyrene (B[a]P) is a member of the polycyclic aromatic hydrocarbon (PAH) family. Although the potent carcinogenicity of high-dose B[a]P has been extensively reported, the effects of long-term exposure to B[a]P on the progression of tongue squamous cell carcinoma (TSCC) are poorly understood. METHODS: In the present study, TSCC cells were treated with 5 or 50 nM of B[a]P for three months. The proliferation and chemoresistance of B[a]P-treated cells to 5-fluorouracil or cisplatin were detected by CCK8. The motility of the B[a]P-treated cells was evaluated with wound healing analysis, invasion assay, and three-dimensional culture in decellularized mouse tongue matrix. Xenograft assay was used to investigate the aggressiveness of B[a]P-treated cells. Immunofluorescence staining, terminal restriction fragment assay, and whole-genome sequence were used to determine the mutation spectrums. RESULTS: Long-term 50 nM B[a]P-treated cells exhibited increased aggressiveness and chemoresistance to 5-fluorouracil or cisplatin. In addition, data from whole-genome sequencing demonstrated that C:T to A:T transitions were the predominant nucleotide substitutions occurred in 50 nM B[a]P-treated CAL27 cells. Furthermore, 102 non-synonymous or stop-gain mutations were enriched in the extracellular-matrix-receptor interactive pathway. CONCLUSIONS: B[a]P exposure may contribute to genomic instability, and therefore, B[a]P may promote the progression of TSCC.

Three-Dimensional Bone Extracellular Matrix Model for Osteosarcoma.

Osteosarcoma (OS) is the most common and a highly aggressive primary bone tumor. It is characterized with anatomic and histologic variations along with diagnostic or prognostic difficulties. OS comprises genotypically and phenotypically heterogeneous cancer cells. Bone microenvironment elements are proved to account for tumor heterogeneity and disease progression. Bone extracellular matrix (BEM) retains the microstructural matrices and biochemical components of native extracellular matrix. This tissue-specific niche provides a favorable and long-term scaffold for OS cell seeding and proliferation. This article provides a protocol for the preparation of BEM model and its further experimental application. OS cells can grow and differentiate into multiple phenotypes consistent with the histopathological complexity of OS clinical specimens. The model also allows visualization of diverse morphologies and their association with genetic alterations and underlying regulatory mechanisms. As homologous to human OS, this BEM-OS model can be developed and applied to the pathology and clinical research of OS.

Fabrication of Tongue Extracellular Matrix and Reconstitution of Tongue Squamous Cell Carcinoma In Vitro.

In order to construct an effective and realistic model for tongue squamous cell carcinoma (TSCC) in vitro, the methods were created to produce decellularized tongue extracellular matrix (TEM) which provides functional scaffolds for TSCC construction. TEM provides an in vitro niche for cell growth, differentiation, and cell migration. The microstructures of native extracellular matrix (ECM) and biochemical compositions retained in the decellularized matrix provide tissue-specific niches for anchoring cells. The fabrication of TEM can be realized by deoxyribonuclease (DNase) digestion accompanied with a serious of organic or inorganic pretreatment. This protocol is easy to operate and ensures high efficiency for the decellularization. The TEM showed favorable cytocompatibility for TSCC cells under static or stirred culture conditions, which enables the construction of the TSCC model. A self-made bioreactor was also used for the persistent stirred condition for cell culture. Reconstructed TSCC using TEM showed the characteristics and properties resembling clinical TSCC histopathology, suggesting the potential in TSCC research.

The lacrimal gland: development, wound repair and regeneration.

The lacrimal gland (LG) is important as it has a significant role in maintaining the stability of the microenvironment of the ocular surface. When a loss of function occurs in the LG, a significant reduction in tear production and dry eye disease (DED) may occur. A mammalian LG is a secretory gland consisting of acini and ducts. The interaction between epithelial cells and mesenchymal cells plays a major role during development and the self-restoration process of the gland. Some factors, such as fibroblast growth factor 10 and bone morphogenetic protein 7, are associated with these processes. Though several strategies for LG regeneration have been established, there is still a long way to go before there is clarity about LG stem cells. In this review, current knowledge on LG development, LG self-repair, DED and correlative regeneration therapies are summarized.