Zinc Absorption by Adults Is Similar from Intrinsically Labeled Zinc-Biofortified Rice and from Rice Fortified with Labeled Zinc Sulfate.

BACKGROUND: Biofortification of staple food crops is a promising strategy to combat zinc deficiency, and it is of particular interest for rice and crops that are not consumed as flours and therefore not suitable for postharvest fortification. Because zinc absorption is decreased by phytic acid (PA) and perhaps other dietary components, it is important to measure the absorption of zinc from a biofortified crop before determining its efficacy. OBJECTIVE: In this study, we compared the zinc absorption from zinc-biofortified rice (hydroponically enriched with (70)Zn) with that from a control rice of the same variety fortified with (70)ZnSO4 at point of use to reach the same total zinc content of 1.1 mg/meal. Both rice meals had a PA:Zn molar ratio of 12. METHODS: Fractional absorption of zinc (FAZ) was measured with the use of the double-isotope tracer ratio method in 16 apparently healthy adults [18-45 y old; BMI (in kg/m(2)) 19-25] who consumed 2 single meals at 4-wk intervals in random order in a crossover design. RESULTS: The FAZ from the biofortified rice (mean ± SD: 25.1 ± 8.7%) did not differ significantly from that of the point-of-use fortified rice (mean ± SD: 20.8 ± 7.1%) (P = 0.08). CONCLUSIONS: These results suggest that the native zinc accumulated in the biofortified rice was readily released from the rice matrix and that its absorption by adults was influenced by PA and other food components in a similar way to the inorganic zinc compound added to the rice at point of use. Moreover, rice biofortification is likely to be as good as postharvest zinc fortification as an intervention strategy to combat zinc deficiency. This trial was registered at clinicaltrials.gov as NCT01633450.

Determinants of vessel contrast in BMI-adapted low dose CT coronary angiography with prospective ECG-triggering.

We evaluated the determinants of vessel contrast in prospectively ECG-triggered CT coronary angiography (CTCA). Seventy patients underwent low-dose CTCA using body mass index (BMI)-adapted tube parameters and a fixed contrast material bolus. Contrast to noise ratio (CNR) was calculated from contrast (between coronaries and perivascular tissue) and image noise (standard deviation of aortic attenuation). Cardiac output (CO) was calculated from gated (99m)Tc-tetrofosmin-SPECT. Mean radiation dose was 2.13 +/- 0.69 mSv. Image noise was not affected by BMI (r = 0.1, P = 0.36), while CNR was inversely related to body surface area (BSA) (r = -0.5, P < 0.001) and CO (r = -0.45, P < 0.001). After successfully overcoming the impact of BMI on image noise by adapting tube parameters, CNR mainly depends on coronary vessel contrast. The latter reflects the dilution of the contrast material by blood volume and CO, which are both correlated to BSA. Therefore, BSA adapted contrast administration may help to compensate for this effect.

Long-term prognostic value of 13N-ammonia myocardial perfusion positron emission tomography added value of coronary flow reserve.

OBJECTIVES: The goal of this study was to assess the predictive value of myocardial perfusion imaging with (13)N-ammonia positron emission tomography (PET) and coronary flow reserve (CFR) on long-term prognosis in patients with suspected myocardial ischemia. BACKGROUND: No prognostic data exist on the predictive value of CFR and (13)N-ammonia PET. METHODS: Perfusion and CFR were assessed in 256 patients using (13)N-ammonia PET, and follow-up was obtained in 245 (96%) patients. Sixteen early revascularized patients were excluded and 229 were assigned to normal versus abnormal perfusion or normal versus abnormal CFR (<2.0). Major adverse cardiac events (MACE) (cardiac death, nonfatal myocardial infarction, late revascularization, or hospitalization for cardiac reasons) were assessed using the Kaplan-Meier method. Cox proportional hazard regression was used to identify independent predictors for cardiac events. RESULTS: During follow-up (5.4 +/- 2.2 years), 78 patients had at least 1 cardiac event, including 29 cardiac deaths. Abnormal perfusion (n = 126) was associated with a higher incidence of MACE (p < 0.001) and cardiac death (p < 0.05). In patients with normal perfusion, abnormal CFR was independently associated with a higher annual event rate over 3 years compared with normal CFR for MACE (1.4% vs. 6.3%; p < 0.05) and cardiac death (0.5% vs. 3.1%; p < 0.05). In abnormal perfusion, CFR remained predictive throughout the 10-year follow-up (p < 0.001). CONCLUSIONS: Perfusion findings in (13)N-ammonia PET and CFR are strong outcome predictors. CFR allows further risk stratification, suggesting a "warranty" period of 3 years if normal CFR is associated with normal perfusion. Conversely, in patients with abnormal perfusion, an impaired CFR has added value for predicting adverse outcomes.