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:

Altered trace mineral milieu might play an aetiological role in the pathogenesis of polycystic ovary syndrome. Insulin resistance is a very common associate of polycystic ovary syndrome (PCOS). Pathophysiology in relation with the essential elements including copper, magnesium, zinc, manganese, chromium, and calcium has been reported in women with insulin resistance. This prospective study was designed to explore whether the women with PCOS do exhibit altered serum element levels in association with/without insulin resistance. One hundred and thirty-two women with PCOS and forty-six control women were studied. Women with PCOS were further divided based on the presence of insulin resistance (insulin resistant: n = 50; non-insulin resistant: n = 82). In all women, basal levels of gonadotropins, prolactin, testosterone, insulin, glucose, and the six different elements were measured. Serum levels of testosterone (p < 0.001), luteinizing hormone (p < 0.05), and fasting insulin (p < 0.004) were significantly higher in the PCOS population compared to controls as well as PCOS women without insulin resistance. Women with PCOS exhibited a significantly high calcium (p < 0.04) and lower manganese levels (p < 0.002) when compared to controls. However, the PCOS women with insulin resistance exhibited significantly lower serum levels of magnesium and chromium (p < 0.04), in addition to higher levels of zinc and copper (p < 0.04). The differences in calcium (p < 0.03) and manganese levels (p < 0.0001) became aggravated with the presence of insulin resistance when compared to control as well as PCOS women without insulin resistance. In PCOS-associated insulin resistance, circulating serum magnesium (r = -0.31; p < 0.03) and chromium (r = -0.38; p < 0.006) status significantly correlated with fasting insulin levels. We conclude that imbalanced element status may be a key foundation for insulin resistance in PCOS. The findings in this study should be investigated with further trials in order to obtain new insights into PCOS.
{"Chemical": ["zinc", "glucose", "calcium", "copper", "chromium", "magnesium", "manganese", "testosterone"]}