Three chick assays were conducted to determine a bioavailable Zn requirement and to establish a Zn relative bioavailability (RBV) value for tetrabasic Zn chloride [TBZC, i.e., Zn5Cl2(OH)8]. In Assay 1, 8-d-old chicks were fed a Zn-deficient soy concentrate diet (8.8 mg/kg bioavailable Zn) supplemented with 0, 5.81, 10.81, 15.10, and 20.25 mg Zn/kg from ZnSO4.7H2O for 14 d to establish a linear ...

Cryptorchism is one of the few well-described risk factors for testicular cancer. It has been suggested that both conditions are related to increased in utero estrogen exposure. The evidence supporting the "estrogen hypothesis" has been inconsistent, however. An alternative hypothesis suggests that higher in utero androgen exposure may protect against the development of cryptorchism and testicu...

This study was performed to determine whether synthetic ascorbic acid (AA) alone or in a natural citrus extract containing bioflavonoids, proteins, and carbohydrates was more bioavailable to human subjects. The effect of a single 500-mg ascorbate dose of the two forms and a placebo citrus extract on plasma ascorbate was examined in eight fasting subjects. A comparison of the areas under the pla...

Although low testosterone levels in men have been associated with high risk for cardiovascular disease, little is known about the association between male sex hormones and subclinical coronary disease in men with apparently low cardiometabolic risk. This study was performed to investigate the association between male sex hormones and subclinical coronary artery calcification measured as coronar...

Total circulating 25-hydroxyvitamin D [25(OH)D)] has been associated with lower risk of colorectal cancer. The physiologic mechanism, however, may be more directly related to the free or bioavailable fraction of 25(OH)D, which is influenced by levels of vitamin D binding protein (VDBP). We assessed the association of prediagnosis total, free, and bioavailable 25(OH)D and VDBP with colorectal ca...

Numerous studies have suggested that there was a significantly positive association between circulating total 25-hydroxyvitamin D (25(OH)D) and survival in colorectal cancer patients. Moreover, plasma vitamin D was also found significantly associated with the concentration of vitamin D binding protein (VDBP). However, there was no paper to clarify the prognostic value of VDBP, free and bioavail...

This study examines the cross-sectional association of hysterectomy and oophorectomy status, chronological age, and years since menopause with plasma levels of total and bioavailable testosterone and estradiol, androstenedione, estrone, and sex hormone-binding globulin (SHBG) in community-dwelling postmenopausal women who were not using estrogen replacement therapy. Six hundred and eighty-four ...

Research on nutrient controls of planktonic productivity tends to focus on a few standard fractions of inorganic or total nitrogen (N) and phosphorus (P). However, there is a wide range in the degree to which land-derived dissolved organic nutrients can be assimilated by biota. Thus, in systems where such fractions form a majority of the macronutrient resource pool, including many boreal inland...

Uremia results in a relatively immunocompromised status, and patients under chronic dialysis have an elevated risk of developing herpes zoster (HZ). We sought to investigate the relationship between vitamin D status and immunity to varicella-zoster virus (VZV). A multicenter prevalent hemodialysis cohort was assembled between 2012 and 2013. We assayed the biochemical parameters, 25-hydroxy- (25...