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The reaction of terephthalaldehyde, p-chloroaniline, and diethyl phosphite in ethyl alcohol solution yields a new crystal (1), CCDC:1405044. This compound is characterized by X-ray single-crystal diffraction, IR, elemental analysis, ESI-MS, and 1H and 13C NMR. Compound 1 crystallizes in the triclinic system, space group P-1 with a = 11.0444(4) Å, b = 12.6468(4) Å, c = 12.7657(4) Å, V = 1627.46(9) Å3, Z = 2, C28H36Cl2N2O6P2, Mr = 629.43, Dc = 1.284 g/cm3, μ = 0.339 mm–1, F(000) = 660, GOOF = 1.101, final R = 0.0875 and wR = 0.1082 for 7381 observed reflections (I > 2σ(I)). The X-ray analysis reveals that the planes of p-chloroaniline and terephthalaldehyde form a dihedral angle of 87.54(0.28)o. In the crystal of compound 1, P atoms have tetrahedral geometries, made up by a double-bond O atom, one Cα atom, and two O-ethyl groups. Besides, Cα atoms are responsible for the existence of the optical activity. Five intramolecular hydrogen bonds helping to stabilize the crystal structure are observed. The interaction between compound 1 and DNA/BSA is also studied. [ABSTRACT FROM AUTHOR]

A new α-aminophosphonate ( 1) was synthesized and its composition and structure were established by EA, FT-IR, ESI-MS, NMR (H, C, and P), and X-ray crystallography. Compound 1 crystallizes in a monoclinic system with space group C2/c. The interaction between α-aminophosphonate ( 1) and bovine serum albumin (BSA) at three different temperatures (298, 303, and 310 K) under simulated physiological condition were studied by fluorescence spectroscopy. The results showed that the fluorescence quenching mechanism between 1 and BSA was a static quenching procedure. The binding constant (K) and binding sites (n) were obtained. The corresponding thermodynamic parameters (ΔH, ΔS, and ΔG) of the interaction system were calculated at different temperatures. The results revealed that the binding process was spontaneous; hydrogen bonds and van der Waals forces were the main forces that stabilize the complex. [ABSTRACT FROM AUTHOR]

PurposeTo study the safety and efficacy of posterior scleral reinforcement (PSR) combined with phakic intraocular lens (PIOLs) implantation for highly myopic amblyopia in children.MethodsThis study included eight highly myopic children (11 eyes) who failed in conventional therapy for amblyopia using various combination of spectacles, contact lenses, and intensive patching before enrollment into this study. They were treated sequentially with PSR and PIOL implantation, and were followed up for 3 years after surgery. Uncorrected visual acuity (UCVA) and best corrected visual acuity (BCVA) in LogMAR, spherical equivalent power (SE), and complications were evaluated.ResultsBefore surgery, the mean UCVA was 1.59±0.33, BCVA, 0.74±0.37, SE, −17.57±5.56D, the axial length (AL), 30.09±2.18 mm. After PSR, BCVA improved one line in three patients, the rest were unchanged, and AL was unchanged among all cases. Six eyes of three patients were implanted with an iris-claw PIOL and five eyes of five patients were implanted with a posterior PIOL. After completion of treatment, the mean UCVA was 0.44±0.21, BCVA 0.38±0.24, SE −0.54±0.74 D, and AL 30.35±2.29 mm. No patient experienced complications.ConclusionCombined PSR and PIOL implantation treatment for highly myopic amblyopia in children is safe and effective. [ABSTRACT FROM AUTHOR]

Three (Cr 1−xAl x)N ( x = 0.33, 0.5, 0.66) coatings were deposited on Ni-super alloy IN718 using reactive magnetron sputtering. The oxidation behavior of all coatings at 900 °C up to 500 h in air was studied. Furthermore, the corrosion behavior of the (Cr 0.33,Al 0.66)N coating at 900 °C (corrosion type I) by spraying a uniform salt scale of Na 2SO 4 on the sample surface (1 mg/cm 2) was investigated. It was found that the coated samples indicate significantly higher oxidation and corrosion resistance compared to uncoated Ni super alloy. This is mainly due to the formation of protective Cr 2O 3 and Al 2O 3 layers on the coating surface. With the increase of Al content, the coatings exhibited improved oxidation resistance. The formation of thin and adherent Al 2O 3 scale on the surface of Al rich coating is the reason for its better oxidation behavior. The detailed structures of the oxide scales and the interdiffusion between coating and substrate were studied using energy dispersive X-ray spectroscopy-analysis. [ABSTRACT FROM AUTHOR]

The hepatitis C viruses (HCVs) are a group of small enveloped RNA viruses that have been viewed as a leading cause of chronic hepatitis in humans. Infections by HCV represent a serious global health problem, because millions of people worldwide are infected and no efficient treatment is available at the present time. Since HCV was identified in 1989, considerable effort has been devoted to the discovery and development of novel molecules to treat HCV-related diseases. One of the approaches is the development of novel inhibitors that interrupt the normal functions of HCV NS5B, an RNA-dependent RNA polymerase essential to HCV replication. This review summarizes recent advances in the biochemical and structural understanding of HCV NS5B polymerase as well as in the development of antiviral agents targeting this important enzyme. [ABSTRACT FROM AUTHOR]

Cyclin-dependent kinase inhibitors are proteins with functions which appear to involve regulation of cell cycle traverse, and have been suggested to have a role in cell differentiation. However, there is as yet no rigorous proof that this is the case. We have addressed the participation of one of these inhibitors, p27Kip1, in the induction of differentiation and the subsequent G1 block induced in HL60 cells by 1,25-dihydroxyvitamin D3 (1,25D3). First, it was noted that sublines of HL60 cells able to grow rapidly in the presence of 1,25D3 have protein levels of p27Kip1 lower than the levels in cells subjected to 1,25D3-induced growth inhibition, but higher than in untreated parental cells. In contrast, there was no discernible relationship between the levels of p27Kip1 and the expression of differentiation markers. Further, HL60 cells treated with 1,25D3 and an oligonucleotide antisense, but not mismatched, to p27Kip1 showed an almost complete elimination of the 1,25D3-induced G1 block, but no decrease in the expression of differentiation markers. Similar results were obtained following transient transfection with an expression vector bearing the entire p27Kip1 coding sequence in the anti-sense orientation. This is the first direct demonstration that p27Kip1 plays a role in the 1,25D3-induced G1 arrest, and that partial reduction in its levels has no effect on the induction of differentiation in HL60 cells. [ABSTRACT FROM AUTHOR]

NiCrAlY coatings with and without CrN or CrON interlayer as diffusion barrier were deposited on superalloy DSM11 by arc ion plating (AIP). The oxidation performance of the coating systems was evaluated by isothermal oxidation tests at 1100 °C for 100 h. The element interdiffusion and oxidation behavior of the coating systems were described. It was found that the NiCrAlY coatings provided protective effect for the DSM11 substrate. However, serious interdiffusion between the coatings and substrate resulted in rapid degradation of the coatings. The addition of CrN or CrON interlayer between the coatings and substrate markedly decreased the interdiffusion. CrON interlayer performed better than CrN interlayer, which was attributed to the excellent diffusion barrier ability of Al2O3 layer formed in the interlayer at high temperature. Also, the NiCrAlY/CrON coating system exhibited more effective protection for DSM11 than the NiCrAlY/CrN coating system. [ABSTRACT FROM AUTHOR]

NiCoCrAlYSiB coatings were deposited on the Co-based superalloy K40 by arc ion plating (AIP). The oxidation behavior of the bare alloy and of the coated specimens was tested in static air for 200 h at 1000 °C and 100 h at 1050 °C. The results showed that the oxidation rate of the system was greatly reduced by the addition of the NiCoCrAlYSiB coatings. Thin and adherent á-A12O3 scales that formed on the coated specimens protected the substrates from further oxidation attack while non-protective oxide scales, mainly of Cr2O3 and CoCr2O4, appeared on bare K40 alloy. Element profiles on metallographic cross sections indicated that apparent interdiffusion occurred between the coatings and the substrates. The interdiffusion behavior and the resulting microstructure were investigated. As compared to aluminide coatings, NiCoCrAiYSiB coatings have less influence on the substrate microstructure. [ABSTRACT FROM AUTHOR]