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Taurine has been shown to have positive effects on bone mass, which are thought to be due in part to its cytoprotective effects on osteoblasts and here we show that taurine also protects osteocytes against cell death due to reactive oxygen species. Using the IDG-SW3 cell line, the expression of the taurine uptake transporter Taut/Slc6a6 is increased during osteoblast to osteocyte differentiation. Taurine had no effect on genes associated with osteoblast to osteocyte differentiation such as Dmp1, Phex or osteocalcin, even at high doses, but a slight yet significant inhibition of alkaline phosphatase was observed at the highest dose (50 mM). No effect was seen on the osteoclast regulatory genes Rankl and Opg, however the wnt antagonist Sost/sclerostin was potently and dose-dependently downregulated in response to taurine supplementation. Taurine also significantly inhibited Dkk1 mRNA expression, but only at 50 mM. Interestingly, osteocytes were found to also be able to synthesize taurine intracellularly, potentially as a self-protective mechanism, but do not secrete the metabolite. A highly significant increase in the expression of cysteine dioxygenase (Cdo), a key enzyme necessary for the production of taurine, was observed with osteoblast to osteocyte differentiation along with a decrease in methionine, the precursor of taurine. For the first time, we describe the synthesis of taurine by osteocytes, potentially to preserve viability and to regulate bone formation through inhibition of sclerostin. Teriparatide (TPTD) reduces risk of both vertebral and nonvertebral fracture, but increases bone mineral density (BMD) much more at the spine than the hip. TPTD and mechanical loading may have a synergistic anabolic effect on BMD, which may help explain these site-specific differences. Under normal daily activity, the femoral neck (FN) is under bending, placing one side under tension and the other under compression. We sought to further understand the relationship between mechanical loading and TPTD at the hip by investigating the effect of tensile versus compressive loading on TPTD stimulated bone formation indices in the human FN. Thirty-eight patients receiving total hip replacements for osteoarthritis were randomized to receive placebo (PBO) or TPTD for a mean treatment duration of 6 weeks prior to surgery, and double tetracycline labeling was administered to allow assessment of bone formation. The FN was harvested during surgery and analyzed for dynamic bone formation indices in the compressive and tensical settings. Variations in drought responses exhibited by cohabiting tree species such as Acer sacharrum and Quercus alba have often been attributed to differences in rooting depth or water accessibility. A. sacharrum is thought to be a shallow rooted species, and is assumed to not have access to the deep and stable water resources available to Q. alba. As such, A. sacharrum conserves water by minimizing stomatal conductance under drought conditions whereas Q. alba does not. However, detailed records of sufficient temporal resolution which integrate water accessibility, meteorological drivers, and leaf level parameters (e.g., photosynthesis, stomatal conductance) are lacking, making such assumptions-though plausible- largely untested. In this study, we investigated the water accessibility of both maples (A. sacharrum) and oaks (Q. alba) during the late growing season using novel canopy stable isotope measurements. Our results showed that maples can draw from the same water pool as cohabitating oaks, but can also switch to a shallow water source in response to available moisture in the shallow soil profile. We also found that maples tended to use a deep water source under high vapor pressure deficit even when shallow soil water was available. On the other hand, oaks had consistent deep water access during our study period. It is noted that our measurements do not cover the whole growing season and should be extrapolated with caution. Such findings indicate that differences in leaf functions during drought between maples and oaks may be due to both soil water accessibility and atmospheric water demand. BACKGROUND AND AIMS We sought to understand the risk factor correlates of very early coronary artery calcium (CAC), and the potential investigational value of CAC phenotyping in adults aged 20-30 years. METHODS We studied all participants aged 20-30 years at baseline (N = 373) in the Coronary Artery Calcium Consortium, a large multi-center cohort study of patients aged 18 years or older without known atherosclerotic cardiovascular disease (ASCVD) at baseline, referred for CAC scoring for clinical risk stratification. We described the prevalence of CAC in men and women, the frequency of risk factors by the presence of CAC (CAC = 0 vs CAC >0), and assessed the association between traditional non-demographic CVD risk factors (hypertension, hyperlipidemia, smoking, family history of CHD, and diabetes) and prevalent CAC, using age- and sex-adjusted logistic regression models. RESULTS The mean age of the study participants was 27.5 ± 2.4 years; 324 (86.9%) had CAC = 0, and 49 (13.1%) had CAC >0. Among the 49 participants with CAC, 38 (77.6%) were men, and median CAC score was low at 4.6. In age- and sex-adjusted models, there was a graded increase in the odds of CAC >0 with increasing traditional cardiovascular disease (CVD) risk factor burden (p = 0.001 for linear trend). Participants with ≥3 traditional risk factors had a statistically significant higher odds of having prevalent CAC (OR 5.57, 95% CI; 1.82-17.03) compared to participants with no risk factors. CONCLUSIONS Our study demonstrates the non-negligible prevalence of CAC among very high-risk young US adults, reinforcing the critical importance of traditional risk factors in the earliest development of detectable subclinical ASCVD. BACKGROUND AND AIMS The long-term comparative results between culprit-only percutaneous coronary intervention (C-PCI) and multivessel PCI (M-PCI) or those between complete revascularization (CR) and incomplete revascularization (IR) in patients with non-ST-elevation myocardial infarction (NSTEMI) and multivessel disease (MVD) after successful newer-generation drug-eluting stent (DES) implantation are limited. ZD1839 Therefore, we compared the 2-year clinical outcomes in such patients. METHODS A total of 4588 patients with NSTEMI and MVD (C-PCI, n = 2055; M-PCI, n = 2533; CR, n = 2029; IR, n = 504) were evaluated. The primary outcome was major adverse cardiac events (MACEs) defined as all-cause death, recurrent myocardial infarction MI, and any repeat coronary revascularization. The secondary outcome was stent thrombosis (ST). RESULTS The cumulative incidences of the primary and secondary outcomes were similar in the three comparison groups (C-PCI vs. M-PCI, CR vs. IR, or CR vs. C-PCI). However, the cumulative incidence of non-target vessel revascularization (non-TVR) was higher in the C-PCI group than in the M-PCI group (adjusted hazard ratio [aHR] 2.