45 research outputs found
Nutritional Metals in Foods by AAS
An overview of the literature will be given of applications of Fame AA together with some
references to Graphite Furnace AA to the analyses of foods such as: meat the main source of
iron; dairy products, the source of calcium and fruit and vegetables for a range of metals.
Comparisons will be given of metal content in these products particularly in meat and dairy
products. Of the metals listed above, not all of these will be considered in every product:
only where they are the metal of highest concentration. The aim of this chapter is to give a
general comparison of the metal content in these products, which will not be exhaustive,
particularly, with respect to fruit and vegetables but the ones most commonly consumed.
The emphasis is on nutrition and to give the general reader and health professional a
concise view of the metal content of these food products. From scientific aspect the
methodology for Flame AA is relative straight forward, as is the work up for instrument
presentation but there are often extra procedures that are required depending on the matrix
that are essential for obtaining a valid result
Pretreatment Serum Concentrations of 25-Hydroxyvitamin D and Breast Cancer Prognostic Characteristics: A Case-Control and a Case-Series Study
Results from epidemiologic studies on the relationship between vitamin D and breast cancer risk are inconclusive. It is possible that vitamin D may be effective in reducing risk only of specific subtypes due to disease heterogeneity.In case-control and case-series analyses, we examined serum concentrations of 25-hydroxyvitamin D (25OHD) in relation to breast cancer prognostic characteristics, including histologic grade, estrogen receptor (ER), and molecular subtypes defined by ER, progesterone receptor (PR) and HER2, among 579 women with incident breast cancer and 574 controls matched on age and time of blood draw enrolled in the Roswell Park Cancer Institute from 2003 to 2008. We found that breast cancer cases had significantly lower 25OHD concentrations than controls (adjusted mean, 22.8 versus 26.2 ng/mL, p<0.001). Among premenopausal women, 25OHD concentrations were lower in those with high- versus low-grade tumors, and ER negative versus ER positive tumors (p≤0.03). Levels were lowest among women with triple-negative cancer (17.5 ng/mL), significantly different from those with luminal A cancer (24.5 ng/mL, p = 0.002). In case-control analyses, premenopausal women with 25OHD concentrations above the median had significantly lower odds of having triple-negative cancer (OR = 0.21, 95% CI = 0.08-0.53) than those with levels below the median; and every 10 ng/mL increase in serum 25OHD concentrations was associated with a 64% lower odds of having triple-negative cancer (OR = 0.36, 95% CI = 0.22-0.56). The differential associations by tumor subtypes among premenopausal women were confirmed in case-series analyses.In our analyses, higher serum levels of 25OHD were associated with reduced risk of breast cancer, with associations strongest for high grade, ER negative or triple negative cancers in premenopausal women. With further confirmation in large prospective studies, these findings could warrant vitamin D supplementation for reducing breast cancer risk, particularly those with poor prognostic characteristics among premenopausal women
Genome-Wide Association of Body Fat Distribution in African Ancestry Populations Suggests New Loci
Central obesity, measured by waist circumference (WC) or waist-hip ratio (WHR), is a marker of body fat distribution. Although obesity disproportionately affects minority populations, few studies have conducted genome-wide association study (GWAS) of fat distribution among those of predominantly African ancestry (AA). We performed GWAS of WC and WHR, adjusted and unadjusted for BMI, in up to 33,591 and 27,350 AA individuals, respectively. We identified loci associated with fat distribution in AA individuals using meta-analyses of GWA results for WC and WHR (stage 1). Overall, 25 SNPs with single genomic control (GC)-corrected p-values<5.0×10−6 were followed-up (stage 2) in AA with WC and with WHR. Additionally, we interrogated genomic regions of previously identified European ancestry (EA) WHR loci among AA. In joint analysis of association results including both Stage 1 and 2 cohorts, 2 SNPs demonstrated association, rs2075064 at LHX2, p = 2.24×10−8 for WC-adjusted-for-BMI, and rs6931262 at RREB1, p = 2.48×10−8 for WHR-adjusted-for-BMI. However, neither signal was genome-wide significant after double GC-correction (LHX2: p = 6.5×10−8; RREB1: p = 5.7×10−8). Six of fourteen previously reported loci for waist in EA populations were significant (p<0.05 divided by the number of independent SNPs within the region) in AA studied here (TBX15-WARS2, GRB14, ADAMTS9, LY86, RSPO3, ITPR2-SSPN). Further, we observed associations with metabolic traits: rs13389219 at GRB14 associated with HDL-cholesterol, triglycerides, and fasting insulin, and rs13060013 at ADAMTS9 with HDL-cholesterol and fasting insulin. Finally, we observed nominal evidence for sexual dimorphism, with stronger results in AA women at the GRB14 locus (p for interaction = 0.02). In conclusion, we identified two suggestive loci associated with fat distribution in AA populations in addition to confirming 6 loci previously identified in populations of EA. These findings reinforce the concept that there are fat distribution loci that are independent of generalized adiposity
Genome-Wide Association of Body Fat Distribution in African Ancestry Populations Suggests New Loci
Central obesity, measured by waist circumference (WC) or waist-hip ratio (WHR), is a marker of body fat distribution. Although obesity disproportionately affects minority populations, few studies have conducted genome-wide association study (GWAS) of fat distribution among those of predominantly African ancestry (AA). We performed GWAS of WC and WHR, adjusted and unadjusted for BMI, in up to 33,591 and 27,350 AA individuals, respectively. We identified loci associated with fat distribution in AA individuals using meta-analyses of GWA results for WC and WHR (stage 1). Overall, 25 SNPs with single genomic control (GC)-corrected p-values<5.0×10−6 were followed-up (stage 2) in AA with WC and with WHR. Additionally, we interrogated genomic regions of previously identified European ancestry (EA) WHR loci among AA. In joint analysis of association results including both Stage 1 and 2 cohorts, 2 SNPs demonstrated association, rs2075064 at LHX2, p = 2.24×10−8 for WC-adjusted-for-BMI, and rs6931262 at RREB1, p = 2.48×10−8 for WHR-adjusted-for-BMI. However, neither signal was genome-wide significant after double GC-correction (LHX2: p = 6.5×10−8; RREB1: p = 5.7×10−8). Six of fourteen previously reported loci for waist in EA populations were significant (p<0.05 divided by the number of independent SNPs within the region) in AA studied here (TBX15-WARS2, GRB14, ADAMTS9, LY86, RSPO3, ITPR2-SSPN). Further, we observed associations with metabolic traits: rs13389219 at GRB14 associated with HDL-cholesterol, triglycerides, and fasting insulin, and rs13060013 at ADAMTS9 with HDL-cholesterol and fasting insulin. Finally, we observed nominal evidence for sexual dimorphism, with stronger results in AA women at the GRB14 locus (p for interaction = 0.02). In conclusion, we identified two suggestive loci associated with fat distribution in AA populations in addition to confirming 6 loci previously identified in populations of EA. These findings reinforce the concept that there are fat distribution loci that are independent of generalized adiposity
Associations of Cumulative Sun Exposure and Phenotypic Characteristics with Histologic Solar Elastosis
Solar elastosis adjacent to melanomas in histologic sections is regarded as an indicator of sun exposure although the associations of ultraviolet (UV) exposure and phenotype with solar elastosis are yet to be fully explored
Analysis of metals in plant parts of selected Chinese herbs by near infrared spectroscopy
Some of the medicinal herbal products may not be required to demonstrate efficacy, safety or quality. Little is known about the relative safety of medicinal herbs compared to synthetic drug treatments, although, for some medicinal herbs the risk may be less than conventional drugs. The toxic effects may show due to heavy metal poisoning. Measurement of metal content in the herbs by standard conventional wet chemical methods usually re-quires numerous reagents, skilled labor and expensive analytical equipment. The objective of this study, therefore, is to study the ability of near infrared spectroscopy (NIRS) to determine the concentrations of lead and zinc in Chinese herbs. The reference values for the Chinese herbs were ob-tained by atomic absorption spectroscopy (AAS). The samples were scanned using a FOSS-NIRSystem (Model 6500) Spectrophotometer from 400-2500 nm. Partial least squares (PLS) and multiple linear regression (MLR) statistics were applied to analyze the data. Coefficient of determination (R2) and Standard error of calibration (SEC) from MLR were Zn (0.74, 0.08), Pb (0.92, 0.04) and from PLS for Zn (0.63, 0.10), Pb (0.90, 0.05), respectively. This preliminary study showed that NIRS is a feasible analytical method for prediction of metal content in various parts of Chinese herbal plants
Metal Analysis of Si Wu Tang in Relation to its Clinical Application
Si Wu Tang, a Chinese herbal formula composed of four Chinese herbs (Danggui, Chuanxiong, Baishao and Shudi) was analysed for its magnesium, manganese, zinc, iron and calcium concentrations when made into a decoction. The commonly prescribed amount is 42 g in a specific ratio of the four herbs, and from this it was determined that all metals analysed were within safe limits and daily tolerable limits would not be able to be reached by ingesting this formula (42 g/day) alone. The highest metal in the Si Wu Tang decoction was found to be magnesium at 25 mg/L, which is under the daily intake recommendations. Varying the brewing time during the preparation of the herbs was found to have various effects on the different micronutrients when made up into separate decoctions from 1 g of each separate herb and these observations may be beneficial to Chinese medicine practitioners who wish to vary the Si Wu Tang formula to better suit a patient’s needs. Samples were analysed at least in triplicate and error was found not to be over 15% at the 95% confidence level. Investigating the amount of metals present will increase the understanding of the levels of these beneficial metals and the potential curative effects they provide