Zircon SHRIMP U-Pb dating on plagiogranite from Kuerti ophiolite in Altay,North Xinjiang

The geochronological study on ophiolites is of great interest due to its tectonic significance. Previous studies have shown that ophiolites can form in various tectonic settings including middle ocean ridge, island arc, forearc and backarc basins; most of them are found in the suprasubduction zone[1,2]. Although the hypothesis that high SiO2 and low K2O granitoid rocks in ophiolites are produced by the fractional crystallization of mafic magma has been proved by experimental simulations[3,4],…     

Ultrasonic measurements of single-crystal gold under hydrostatic pressures up to 8 GPa in a Kawai-type multi-anvil apparatus

Ultrasonic measurements were conducted on single-crystal gold at ambient condition and hydrostatic pressures up to 8 GPa at room temperature in a Kawai-type multi-anvil apparatus. The P-wave velocities measured at high pressures were in good agreement with Daniels and Smith’s ultrasonic study. The three independent elastic constants of gold at ambient condition were determined to be C11=192.7 GPa, C12=162.9 GPa, and C44=42.4 GPa. On the basis of an analysis of previous elastic data and the present ultrasonic data, the pressure derivatives of three elastic constants were estimated to be C1 ′1= 7.12,C 1′2 = 6.24,and C4′4 = 1.82. The calculated values of isothermal bulk modulus (KT0) and its pressure derivatives ( KT ′0) are KT0 = 166.44 GPa and KT ′0= 6.56. This indicates that Anderson et al.’s model of equation of state of gold might underestimates pressure about 1 GPa at pressure around 23 GPa and ambient temperature. Our results explained the discrepancies among the models of equation of state of gold proposed previously.     

A genome-wide association study identifies two susceptibility loci for duodenal ulcer in the Japanese population

Through a genome-wide association analysis with a total of 7,035 individuals with duodenal ulcer and 25,323 controls from Japan, we identified two susceptibility loci at the PSCA gene (encoding prostate stem cell antigen) at 8q24 and at the ABO blood group locus at 9q34. The C allele of rs2294008 at PSCA was associated with increased risk of duodenal ulcer (odds ratio (OR) = 1.84; P = 3.92 × 10(-33)) in a recessive model but was associated with decreased risk of gastric cancer (OR = 0.79; P = 6.79 × 10(-12)), as reported previously. The T allele of rs2294008 encodes a translation initiation codon upstream of the reported site and changes protein localization from the cytoplasm to the cell surface. rs505922 at ABO was also associated with duodenal ulcer in a recessive model (OR = 1.32; P = 1.15 × 10(-10)). Our findings demonstrate a role for genetic variants in the pathogenesis of duodenal ulcer.     

Regulation of oxidative stress by ATM is required for self-renewal of haematopoietic stem cells

The 'ataxia telangiectasia mutated' (Atm) gene maintains genomic stability by activating a key cell-cycle checkpoint in response to DNA damage, telomeric instability or oxidative stress. Mutational inactivation of the gene causes an autosomal recessive disorder, ataxia-telangiectasia, characterized by immunodeficiency, progressive cerebellar ataxia, oculocutaneous telangiectasia, defective spermatogenesis, premature ageing and a high incidence of lymphoma. Here we show that ATM has an essential function in the reconstitutive capacity of haematopoietic stem cells (HSCs) but is not as important for the proliferation or differentiation of progenitors, in a telomere-independent manner. Atm-/- mice older than 24 weeks showed progressive bone marrow failure resulting from a defect in HSC function that was associated with elevated reactive oxygen species. Treatment with anti-oxidative agents restored the reconstitutive capacity of Atm-/- HSCs, resulting in the prevention of bone marrow failure. Activation of the p16(INK4a)-retinoblastoma (Rb) gene product pathway in response to elevated reactive oxygen species led to the failure of Atm-/- HSCs. These results show that the self-renewal capacity of HSCs depends on ATM-mediated inhibition of oxidative stress.     

Effects of kallidinogenase on urinary kallikrein excretion and plasma prostanoid concentrations in patients with essential hypertension

Summary The effects of kallidinogenase on urinary kallikrein excretion, plasma immunoreactive prostanoids and platelet aggregation were investigated in patients with essential hypertension. Urinary kallikrein excretion and plasma 6-keto PGF₁ concentration were significantly decreased in these patients. Significant decreases in blood pressure, as well as significant increases of urinary kallikrein excretion and plasma 6-keto PGF₁ concentration after kallidinogenase administration were also observed.     

A possible pathway for the biosynthesis of adenochromines

Summary 5-Thiolhistidine reacted with dopaquinone produced in vitro by tyrosinase oxidation of dopa to give high yields of secoadenochromines (3) along with a small amount of adenochromines (1) which are the amino-acids responsible for the iron-(III)-binding properties of adenochromes.Istituto di Chimica dell'Università di Napoli. This work was partially supported by C.N.R. (Rome) within the project Oceanografia e Fondi Marini. The authors gratefully acknowledge the technical assistance of Mr Vittorio Milo.     

Catalysis on Interface of Nano-oxide and Nano-zeolite

1 Results The catalysts which can efficiently hydro-reform higher n-paraffin to lower isoparaffins for environmentally-friendly gasoline were studied. The catalysts were examined by the conversion of n-hexadecane, n-C16H34 to i-C6H14—i-C10H22.The tri-modally nano-porous catalysts composed of (Ni-Mo)/[γ-Al2O3], nano-oxide, and nano-crystalline zeolite had some active and selective performance because of the interface between nano-oxide and nano-zeolite. The catalyst composed of nano-crystalline MFI or BE...