"INTRODUCTION: We evaluated the ratio of free to total prostate-specific antigen (PSA) and PSA to protein concentrations in saliva and serum of healthy men. MATERIALS AND METHODS: Concentrations of protein, free PSA, and total PSA in serum and saliva were measured in 30 healthy men aged 42 to 73 years, and their ratios were compared between the two fluids. RESULTS: There was a significant direct correlation between serum free-total PSA ratios of serum and saliva (P = .04) and between total PSA-protein ratios of serum and saliva (P = .02).

"Dysregulated expression of microRNAs (miRNAs) in various tissues has been associated with a variety of diseases, including cancers. Here we demonstrate that miRNAs are present in the serum and plasma of humans and other animals such as mice, rats, bovine fetuses, calves, and horses. The levels of miRNAs in serum are stable, reproducible, and consistent among individuals of the same species. Employing Solexa, we sequenced all serum miRNAs of healthy Chinese subjects and found over 100 and 91 serum miRNAs in male and female subjects, respectively.

INTRODUCTION: We evaluated the ratio of free to total prostate-specific antigen (PSA) and PSA to protein concentrations in saliva and serum of healthy men. MATERIALS AND METHODS: Concentrations of protein, free PSA, and total PSA in serum and saliva were measured in 30 healthy men aged 42 to 73 years, and their ratios were compared between the two fluids. RESULTS: There was a significant direct correlation between serum free-total PSA ratios of serum and saliva (P = .04) and between total PSA-protein ratios of serum and saliva (P = .02).