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Accurate measurement of endogenous steroid hormones in serum is a powerful tool for understanding the status of human adrenal diseases. Isotope dilution–liquid chromatography–tandem mass spectrometry is the most commonly used method for determination of steroids in serum. In this study, we used a laboratory-constructed quadrupole-linear ion trap (Q-LIT) tandem mass spectrometer to develop a new method for the quantification of five steroid hormones in serum. A simple and efficient pretreatment was improved, wherein the serum was extracted once by a mixed solvent of 1.0 mL of ethyl acetate and n-hexane. Using the optimized method, the regression coefficients of the calibration curves were all higher than 0.99, the limits of detection were from 0.31 to 1.25 ng mL−1, and the limits of quantification were between 1.00 and 2.50 ng mL−1. The intra-day (n = 3) relative standard deviations ranged from 4.24% to 13.79%, and the inter-day (n = 3) relative standard deviations from 3.99% to 11.43%. After internal standard correction, the relative recoveries of all steroids were from 86.08% to 106.60%. Twenty-two serum samples were analyzed by Q-LIT, which was compared with commercial triple quadrupole mass spectrometer. The results of the instruments had high consistency. Therefore, Q-LIT accurately quantified steroid hormones in human samples and may be used for clinical diagnosis and monitoring of hormone-dependent diseases. [ABSTRACT FROM AUTHOR]

Oxidation of sulfide to sulfone is a fundamental process to produce many important pharmaceutical compounds. Formerly, efficient methods have been reported for the synthesis of sulfones from sulfides. Yet some limitations were identified, such as the unbalance use of metal catalysts and expensive oxidizing agent, low reaction yields and production of by-products. In this current research, oxidation of sulfides to sulfones is described in the presence of samarium oxide (Sm2O3) along with hydrogen peroxide. The SEM image showed the crystalline morphology of the Sm2O3 as a cubic single phase (ICSD 98-001-2948) with a size distribution between 120 and 300 nm. In the recyclability experiment, Sm2O3 catalyst can be reutilized for five successive cycles and afforded the desired end-products in great yields (97–95%). This current work is vital, as the usage of non-endangered metals in organic transformation is geared towards achieving the elemental sustainability concept. [ABSTRACT FROM AUTHOR]

Autophagy has emerged as a key regulator of cell metabolism. Recently, we have demonstrated that autophagy is involved in RNA metabolism by regulating ribosomal RNA (rRNA) synthesis. We found that autophagy-deficient cells display much higher 47S precursor rRNA level, which is caused by the accumulation of SQSTM1/p62 (sequestosome 1) but not other autophagy receptors. Mechanistically, SQSTM1 accumulation potentiates the activation of MTOR (mechanistic target of rapamycin kinase) complex 1 (MTORC1) signaling, which facilitates the assembly of RNA polymerase I pre-initiation complex at ribosomal DNA (rDNA) promoter regions and leads to the activation of rDNA transcription. Finally, we showed that SQSTM1 accumulation is responsible for the increase in protein synthesis, cell growth and cell proliferation in autophagy-deficient cells. Taken together, our findings reveal a regulatory role of autophagy and autophagy receptor SQSTM1 in rRNA synthesis and may provide novel mechanisms for the hyperactivated rDNA transcription in autophagy-related human diseases. Abbreviations: 5-FUrd: 5-fluorouridine; LAP: MAP1LC3/LC3-associated phagocytosis; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; MTOR: mechanistic target of rapamycin kinase; PIC: pre-initiation complex; POLR1: RNA polymerase I; POLR1A: RNA polymerase I subunit A; rDNA: ribosomal DNA; RRN3: RRN3 homolog, RNA polymerase I transcription factor; rRNA: ribosomal RNA; SQSTM1/p62: sequestosome 1; TP53INP2: tumor protein p53 inducible nuclear protein 2; UBTF: upstream binding transcription factor. [ABSTRACT FROM AUTHOR]

Mesoporous silica SBA-15 (with ~6 nm pore size and ~6 nm wall thickness) was exposed to a hydrothermal environment at 2 and 5 GPa. The p,T quenched products were investigated by powder X-ray diffraction and transmission electron microscopy. Infrared spectroscopy and thermogravimetric analysis of a sample subjected to 5 GPa at room temperature suggests functionalization of both inner and outer pore surface by silanol. Partial transformation to nano-sized (20-50 nm) coesite crystals with nonfaceted morphology was observed during short equilibration times of 2 h at 125°C, which is significantly below the melting point of water (~250°C). Untransformed SBA-15 maintained intact pore structure. At 175°C and during 8 h, SBA-15 transformed completely into faceted coesite crystals with dimensions 100-300 nm, suggesting Ostwald ripening and thus significant mass transport in the solid water environment. At 2 GPa the melting point of water is near 70°C. Partial transformation to nano-sized α-quartz was observed at 65°C and during 2 h. Untransformed SBA-15 partially pore collapsed. The reduced pore stability of SBA-15 at 2 GPa is attributed to the presence of liquid water in the pores due to melting point depression of confined water. [ABSTRACT FROM AUTHOR]

Equivalent alkane carbon number (EACN) of crude oil reflects the hydrophobicity of the crude oils, thus it would be helpful to estimate the EACN of crude oil before fine tuning the surfactant selection for enhanced oil recovery field application. In this study, we used the titration methodology to quantify the EACN values for several crude oil samples retrieved from the targeted mature oil fields. The results showed that the method of using extended surfactant was simpler but reliable to determine the EACN of crude oils. The resulting EACN for these crude oils was found to be in the range of 6.0–11.3. [ABSTRACT FROM PUBLISHER]

Phospholipase D1 (PLD1) is an enzyme of the phospholipase D (PLD) superfamily. It is involved in the occurrence of various tumors. However, its role in multiple myeloma (MM) remained undefined. This study aimed to investigate the mechanism of PLD1 in the therapy of myeloma disease. Cell lines U266 and H929 were treated with PLD1 specific inhibitor VU0359595 combined bortezomib, a proteasome inhibitor. Their effects on MM cell proliferation, apoptosis, and relevant signal pathways of apoptosis were determined by cell counting kit-8 (CCK-8), real-time polymerase reaction chain (RT–PCR), ATP assay, and western blot. PLD1 was highly expressed in U266 and H929 cells. VU0359595 didn't affect the proliferation and apoptosis of MM cells. However, VU0359595 could enhance growth inhibition, decreasing mitochondrial membrane potentials (MMPs) and ATP levels of bortezomib treated MM cells. VU0359595 also strengthened bortezomib-induced apoptosis via activating caspase-8, caspase-9, caspase-3; and down-regulating the expressions of anti-apoptosis proteins BCL-2. In addition, the bortezomib-induced cytotoxicity on MM cells was significantly augmented by VU0359595 through efficient suppression of the mTOR/NF-κB signal pathway. PLD1 inhibition can remarkably exert antitumor effects with bortezomib on MM, which is a novel potentially targeting therapeutic agent, especially for drug-resistant MM patients. [ABSTRACT FROM AUTHOR]

The sequenced mitochondrial genome of the threatened alpine butterflyParnassius nomionincludes 13 protein-coding genes (ND1-6, COI-III, ATP6, ATP8, ND4, ND4L, CTYB), 2 ribosomalRNAs (12 Sand16 S), 22 transferRNAs, which is 14,547 bp in length. Its gene order and orientation are identical to the common type found in most of other completely sequenced lepidopteran mitogenomes. All protein-coding genes are initiated by ATN codons, except forCOI, which uses CGA as its start codon. Eleven PCGs use the standard TAA as their termination codon, andCOI, COIIuse the incomplete termination codon T. [ABSTRACT FROM AUTHOR]

The sequenced mitochondrial genome of the cabbage webwormHellula undalisincludes 13 protein-coding genes (PCGs) (nad1-6, cox1-3, atp6, atp8, nad4Landcob), two ribosomalRNAs (12Sand16S) and 19 transferRNAs, which is 14,678 bp in length. Its gene order and orientation are identical to the common types found in most of the other completely sequenced lepidopteran mitogenomes. Thirteen PCGs start with a typical ATN codon, whilecox1uses CGA as its start codon. Some PCGs use the standard TAA as their termination codon, while others use the incomplete termination codon T (cox1, cox2andnad4). [ABSTRACT FROM AUTHOR]

Digital Earth is an important field of information technology and a research frontier of geosciences in the 21st century. So far, the Grid computing technique is one of the best solutions for Digital Earth infrastructure. Digital Earth can only be realised through the interaction of people, heterogeneous computing resources, information systems, and instruments, all of which are geographically and organisationally dispersed. Earth observation (EO) includes information acquisition, processing and applications. Information acquisition provides a vast amount of spatial data for building the fabric resource infrastructure. Information processing means that spatial information processing middleware is used with large amounts of secure Grid computing resources for real-time processing of all kinds of spatial data. We are currently working on the development of core-middleware for EO data processing and applications for the Digital Earth Prototype System, which is available in the Institute of Remote Sensing Applications (IRSA), Chinese Academy of Sciences (CAS) The further results will be available soon. [ABSTRACT FROM AUTHOR]

Based on the inspirations that slickwater volume fracturing can produce and communicate microfractures, acid fracturing is applied to carbonate rocks by using composite osmotic acid with large displacement and low friction. The drag reducing agent P(AM-DMC-DMAM) was synthesized by acrylamide, N,N-dimethylacrylamide and methacryloyloxyethyl trimethylammonium chloride as the main monomer through free radical polymerization. And the structure was characterized by infrared spectroscopy and 1H NMR. A composite osmotic acid was prepared with drag reducing agents and high-efficiency penetrants as the main agent. The results of the drag reducing and rheological tests show that when the flow rate is 51.70 L/min, the drag reduction rate can reach 70%, and the viscosity of the acid solution after shearing at 170 s−1 and 140 °C for 90 min is 10mPa·s. The results of core permeability and solid damage analysis show that acid has excellent performance on communication to core and its microfractures. The corrosion performance study show that the maximum corrosion rate is 7.05 g/(m2·h), and the pitting factor is around 1.3. The acid etched fracture conductivity is still 4.8μm2·cm when the closing pressure reaches 60.0 MPa. [ABSTRACT FROM AUTHOR]