You will be shown an abstract from a biomedical research paper. Given this abstract, your task is to extract all unique entities of the following types: ["Chemical"].

Please return the output as a JSON object of the format: {"Chemical": ["Arsenic", ...]}. The keys should be entity types and values should be lists of extracted entities belonging to the corresponding type. If you cannot find entities belonging to a specific type, the value should be [].

Only output the JSON object and do not include any additional text.

Abstract:

The 2,2',4,4'-tetrabromodiphenyl ether hydroxylated metabolites 5-OH-BDE-47 and 6-OH-BDE-47 stimulate estradiol secretion in the ovary by activating aromatase expression. The aim of the present study was to assess the effect of two hydroxylated BDE-47 metabolites, 5-OH-BDE-47 and 6-OH-BDE-47, on steroidogenesis in the ovary. Both metabolites failed to affect the production of androstenedione and testosterone but increased the secretion of estradiol at all concentrations tested. The increased secretion of estradiol was due to the stimulation of aromatase gene and protein expression. Direct assessment of aromatase activity by dibenzylfluorescein assay and indirect assessment of aromatase activity by measurement of the conversion of testosterone to estradiol confirmed that 5-OH-BDE-47 and 6-OH-BDE-47 stimulate aromatase activity. The aromatase inhibitor CGS 16949A abolished this stimulatory activity and reduced estradiol levels in the control and treatment groups.
{"Chemical": ["hydroxylated BDE-47", "6-OH-BDE-47", "dibenzylfluorescein", "androstenedione", "2,2\u0027,4,4\u0027-tetrabromodiphenyl ether", "estradiol", "CGS 16949A", "5-OH-BDE-47", "testosterone"]}