RESUMO
The Moche civilization in Peru developed marvelous metallurgy, primarily using alloys of gold, copper and silver, with the most famous of them called Tumbaga, which resembles pure gold after a depletion process on its surface. However, they also created objects with more standard single-layer alloys or gilding. To distinguish between these techniques in a non-destructive manner is essential. Here, we analyzed a thigh protector, composed of two parts, one seemingly in silver and the other seemingly in gold. The sample was analyzed using X-ray fluorescence measurements integrated with Monte Carlo simulation. The results show that the silver part is formed of a silver-based alloy covered in a corrosion layer, while the gold part is made of Tumbaga. Moreover, for the first time, the gold profiles of different Tumbaga gold objects, from the same burial, were compared, allowing us to obtain information about the standardization of their manufacture.
RESUMO
BACKGROUND: High-mobility group AT-hook 1 (HMGA1) is an important regulator of the insulin receptor gene. We have previously shown in three populations of white European ancestry that the HMGA1 gene variant rs146052672 (also designated IVS5-13insC) is associated with type 2 diabetes mellitus (T2DM). The aim of this study was to measure the frequency of this variant and to determine the degree of the association with T2DM and other features of the metabolic syndrome in a replication cohort of Hispanic Americans. METHODS: This was a retrospective cohort study of well-characterized Hispanic-American participants analyzed in the Genomic Resource in Atherosclerosis (GRA) (Cardiovascular Research Institute, University of California, San Francisco). A total of 1144 individuals were studied, 320 of whom had T2DM. We examined associations of the rs146052672 SNP with T2DM, plasma lipids, lipoproteins, and body mass index (BMI). RESULTS: In this Hispanic-American cohort, the HMGA1 rs146052672 minor allele (C-insertion) frequency (MAF) was 21.4% with a carrier frequency of 37.4%, considerably higher than we previously observed among GRA white Europeans (MAF 3.1%). The prevalence of the IVS5-13insC variant was significantly higher in those with T2DM compared to controls [42.2% vs. 35.5%; odds ratio (OR) 1.44 95% confidence interval (CI) 1.09-1.90, P=0.011). The variant was also associated with BMI (positively, P=0.045) and plasma high-density lipoprotein cholesterol (HDL-C) (negatively, P=0.047). CONCLUSIONS: As we saw previously among white Europeans, a functional HMGA1 variant was associated with T2DM in individuals of Hispanic-American ethnicity and was present at a much higher frequency.