Abstract. Polycyclic aromatic hydrocarbons (PAHs) and dioxins are ubiquitous environmental pollutants and activate the aryl hydrocarbon receptor (AhR), a ligand-activated transcription factor. It has been reported that testosterone represses 2,3,7,8-tetrachlorodibenzo-p-dioxininduced transcription of the cytochrome P450 (CYP) 1A1 gene in LNCaP cells. In this study, we investigated the mechanism for the repression of 3-methylcholanthrene (3MC)-induced transcription of AhR-regulated genes, CYP1A1, CYP1A2, CYP1B1, and AhR repressor (AhRR), by 5α-dihydroteststerone (DHT) in LNCaP and T47D cells, which are androgen receptor (AR)-and AhR-positive. Real-time PCR analysis showed that DHT repressed 3MC-induced mRNA expression of the CYP1 family and AhRR genes. DHT repressed 3MC-induced luciferase activity in an AhR response element-driven luciferase reporter assay in LNCaP and T47D cells. The inhibitory effect of DHT was abolished by knockdown of AR protein with siRNA. The protein levels of AhR and AhR nuclear translocator (Arnt), the AhR-dimerizing partner, were not affected by DHT. Co-immunoprecipitation assay showed that DHT significantly facilitated the complex formation between AR and AhR in 3MC-treated cells. These results suggest that complex formation between activated AR and AhR plays an important role in the suppression of 3MC-induced transcription of CYP1 family genes by DHT.

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Zeolite-templated carbons (ZTCs) with high surface areas of ≥3750 m 2 g −1 are facilely synthesized from sugars and propylene as carbon sources using NaY zeolite as a template. The zeolite need not be previously dried to remove adsorbed water and can be directly mixed with sugars. The mixture is subject to chemical vapor deposition (CVD) of propylene at 700 °C and subsequent heat treatment at 900 °C, followed by HF etching for zeolite removal. In this study, α-D-glucose, β-D-glucose, D-xylose, Dfructose, and D-sucrose are examined, and a necessary amount of all the sugars per 1 g of the zeolite is reduced to only 0.32 cm 3 , which corresponds to the total pore volume of the zeolite, for maximizing the surface area and structural regularity of ZTC. Upon heating, adsorbed water desorbs from the zeolite, and the sugars are adsorbed inside the micropores of the zeolite below 300 °C. The adsorbed sugars are carbonized into nanographenes, and the nanographenes are extended and interconnected together via a graphene growth reaction during the CVD. Consequently, the threedimensionally ordered and interconnected pore structure with a uniform pore size of 1.2 nm is recovered by HF etching, yielding 0.3 g of ZTC per 1 g of the zeolite. The present synthetic method does not require any solvents for adsorption of sugars, and therefore, high surface area ZTCs would become widely and readily available as adsorbents and electrodes for practical applications and fundamental studies.

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