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Background: Anaplastic thyroid cancer (ATC) is a rare but one of the most lethal types of human cancer. Although increasing evidence demonstrated that ATC tumors had a high mutation burden, little is known about the aberrancy of the noncoding genome of ATC except the well-investigated telomerase reverse transcriptase (TERT) promoter mutations. Methods: The mutational statuses of TBC1D12 5′ untranslated region (5′UTR), GPR126 intron 6, SDHD and PLEKHS1 promoters, as well as the TERT promoter and BRAFV600E mutations were determined using Sanger sequencing in 28 patients with ATC (19 women and 9 men) with a median (interquartile range) age of 64 (55–71) years, 14 thyroid cancer cell lines and a normal thyroid cell line. The prevalence of TBC1D12 5′UTR mutations in papillary thyroid cancer (PTC) and their association with clinicopathologic characteristics were explored by analyzing The Cancer Genome Atlas thyroid cancer dataset. Results: The noncoding mutations in TERT, SDHD and PLEKHS1 promoters, TBC1D12 5′UTR, and GPR126 intron 6 were collectively found in 82.1% (23/28) of ATC samples. Specifically, TERT promoter mutations were detected in 22 (78.6%) samples; GPR126 intron mutations were detected in 2 (7.1%) samples; and both SDHD and PLEKHS1 promoter mutations were detected in 1 (3.6%) ATC sample. Two hotspot mutations in TBC1D12 5′UTR were observed in 14 of 28 (50%) ATCs, 7 of 492 (1.4%) PTCs, and 1 cell line derived from ATC. TBC1D12 5′UTR mutations were significantly associated with older age at diagnosis (60 vs. 46 for wild type, p = 0.003), pathological T3/T4 stage (85.7% vs. 37.7%, p = 0.010), and advanced tumor stages (85.7% vs. 32.5%, p = 0.006) in PTC. Conclusions: This preliminary study for the first time showed a high prevalence of TBC1D12 5′UTR mutations in ATC and indicated an association between TBC1D12 mutation and aggressive characteristics of PTC, which needs to be confirmed in large cohort studies. [ABSTRACT FROM AUTHOR]

There are many areas in the world where ground water has been contaminated by arsenic. MnO2 is one of the most inexpensive materials which can both adsorb arsenic and oxide arsenite [As(III)] to arsenate [As(V)]. In this study, the Ultra-long α-MnO2 nanowires with the (1 1 0) surface are used to remove As(III) and As(V) from solutions under different conditions. The adsorption kinetics for both As(III) and As(V) fit well with the pseudo-second-order kinetic model. For example, the pseudo-second-order adsorption kinetic constants are 0.076 × 103 and 0.077 × 103 g μg−1 min−1 at pH 7 for As(III) and As(V), respectively. At the same time, compared to the Freundlich model the Langmuir model better describes the adsorption equilibrium isotherms. For example, the maximum adsorption capacity values of the α-MnO2 nanowires obtained from the Langmuir model are 1.012 × 103 and 1.158 × 103 μg g−1 at pH 7 for As(III) and As(V), respectively. The adsorption capacities of α-MnO2 nanowires are affected by the pH value and increase with the initial arsenic concentration. Furthermore, the As(III) oxidation rate can be denoted by the pseudo-zero-order kinetic model and is related to O2 concentration, the light source used, the initial concentration of As(III), and the pH value. For example, the pseudo-zero-order kinetic equation is y = −0.90x + 163.6 with 4 L min−1 of O2, dark condition, 0.2 × 103 μg L−1 of As(III) and at pH 7. Finally, the oxidation mechanism is investigated and the oxidant in this reaction should be related with O2 not Mn(II). Besides its special structure and easy separation ability, it is a promising material to remove arsenic from water. [ABSTRACT FROM AUTHOR]

TiO2-based materials are important photocatalysts but the rapid recombination of photoexcited electron–hole pairs, and the wide band gap both limit their photocatalytic activities. In this work, p-type phosphorus-doped graphene quantum dots (P-GQDs, 5~20 nm) were combined with n-type TiO2 nanoparticles (20~50 nm) and n-type silver iodide (AgI, 100~200 nm) by a facile sonication and precipitation process to yield a novel ternary photocatalyst TiO2/P-GQDs/AgI with n-p-n heterojunctions. The morphologies, structures, optical properties, and chemical environments of photocatalysts were all studied. The resulting ternary photocatalyst exhibited enhanced visible photocatalytic activity toward the degradation of methyl orange (MO), estimated to 70.4-fold that of pure TiO2. By contrast, the photocatalytic activities of TiO2/GQDs with an n-n heterojunction, TiO2/P-GQDs with a p-n heterojunction, and TiO2/GQDs/AgI (30%) with an n-n-n heterojunction showed 4.4-fold, 5.3-fold, and 14.2-fold higher than those of TiO2. The electrochemical and optical measurements revealed that the enhanced photocatalytic activity was linked to promoted charge carrier separation by n-p-n heterojunctions coupled with the increased absorption in the visible region. Overall, the new band structure connected in series p-n heterojunctions looks promising as a highly efficient photodegradation system for future use in decontamination of polluted water. [ABSTRACT FROM AUTHOR]