Search results for "Lytic"

Pharmacogenomic Characterization of Cytotoxic Compounds from Salvia officinalis in Cancer Cells.

2015

Salvia officinalis is used as a dietary supplement with diverse medicinal activity (e.g. antidiabetic and antiatherosclerotic effects). The plant also exerts profound cytotoxicity toward cancer cells. Here, we investigated possible modes of action to explain its activity toward drug-resistant tumor cells. Log10IC50 values of two constituents of S. officinalis (ursolic acid, pomolic acid) were correlated to the expression of ATP-binding cassette (ABC) transporters (P-glycoprotein/ABCB1/MDR1, MRP1/ABCC1, BCRP/ABCG2) and epidermal growth factor receptor (EGFR) or mutations in RAS oncogenes and the tumor suppressor gene TP53 of the NCI panel of cell lines. Gene expression profiles predicting se…

Corrosion and wear resistance of coatings produced on AZ31 Mg alloy by plasma electrolytic oxidation in silicate-based K2TiF6 containing solution: Ef…

2022

Abstract In this research, plasma electrolytic oxidation coatings were prepared on AZ31 Mg alloy in a silicate-based solution containing K2TiF6 using bipolar and soft sparking waveforms with 10, 20, and 30% cathodic duty cycles. The coatings displayed a net-like surface morphology consisted of irregular micro-pores, micro-cracks, fused oxide particles, and a sintered structure. Due to the incorporation of TiO2 colloidal particles and the cathodic pulse repair effect, most of the micro-pores were sealed. Long-term corrosion performance of the coatings was investigated using electrochemical impedance spectroscopy during immersion in 3.5 wt.% NaCl solution up to 14 days. The coating grown by t…

Study of the electronic and atomic structure of thermally treated SrTiO3(110) surfaces

2003

The electronic structure of heated SrTiO3(110) surfaces was investigated with metastable impact electron spectroscopy and ultraviolet photoelectron spectroscopy (He(I). Scanning tunnelling microscopy and atomic force microscopy (AFM) were used to study the topology of the surface. The crystals were heated up to 1000 °C under reducing conditions in ultrahigh vacuum or under oxidizing conditions in synthetic air for 1 h, respectively. Under both conditions microfacetting of the surface is observed. The experimental results are compared with ab initio Hartree-Fock calculations, also presented here, carried out for both ideal and reconstructed SrTiO 3(110) surfaces. The results give direct evid…

Smooth structures on algebraic surfaces with cyclic fundamental group

1988

Analysis of emerging and related pollutants in aquatic biota

2020

Water bodies cover approximately 70 % of the earth s surface, making them ecosystems with a high environmental value and the habitat for numerous species of flora and fauna. Emerging pollutants (EPs) are ubiquitous anthropogenic compounds of environmental concern that can be found at different concentration levels in matrices such as sediment, water and aquatic biota. In addition, EPs can be bioaccumulated and biomagnified, inducing adverse effects on biota, and posing a risk to humans when contaminated biota is consumed. Unlike abiotic matrices, the occurrence of EPs in aquatic biota has not been widely studied. This is probably because their complexity, due to the presence of lipids, prot…

Sr-isotope analysis of speleothems by LA-MC-ICP-MS: High temporal resolution and fast data acquisition

2017

Speleothems are well established climate archives. A wide array of geochemical proxies, including stable isotopes and trace elements are present within speleothems to reconstruct past climate variability. However, each proxy is influenced by multiple factors, often hampering robust interpretation. Sr isotope ratios (87Sr/86Sr) can provide useful information about water residence time and water mixing in the host rock, as they are not fractionated during calcite precipitation. Laser ablation multi-collector-inductively coupled plasma mass spectrometry (LA-MC-ICP-MS) has rarely been used for determination of Sr isotope signatures in speleothems, as speleothems often do not possess appropriate…

<title>Hardening in LiF, induced by fast Kr and Ni ions, and recovery of the structure and properties under annealing</title>

2005

The recovery of optical and mechanical properties of LiF crystals irradiated with 790 MeV 78Kr and 640 MeV 58Ni ions at 10l2 ions/cm2 under annealing at temperatures up to 810 K is investigated. The optical absorbance and depth profiles of hardness before and after annealing were measured. A marked recovery of hardness and change in the optical absorption spectra were observed at temperatures above 520-530 K. An activation energy of 0.15±0.02eV, which is close to that for the thermal migration of H centers, is obtained from the annealing data. The results indicate a significant role of the H-center aggregates in the hardening and annealing processes. The maximum hardening is created and the…

Systematic Study of Several Causes and Effects Due to Absorbent Blanks in Determinations of One Analyte

1999

A systematic study is performed about several factors involved in the measurements when a absorbent blank is used, as molar absorption coefficient of the formed complex, absorbance of the blank at the measured wavelength, and kind of spectrophotometer used (conventional double-beam or diode-array). It is proved that the usual methodology, measuring against reagent blank, produces less accurate measurements than those obtained against solvent blank. On the other hand, use of the H-Point standard additions method provides always equal or better results than the best ones obtained at single wavelengths by using measurements against solvent bank, at the maximum of the formed complex. To test th…

Solid sampling Fourier transform infrared determination of Mancozeb in pesticide formulations

2004

Abstract A series of approaches have been assayed for FTIR determination of Mancozeb in several solid commercial fungicides using different calibration strategies. The simplest procedure was based on the use of the ratio between the absorbance of a characteristic band of Mancozeb and that of a KSCN internal standard measured in the FTIR spectra obtained from KBr pellets. It was employed the quotient between peak height absorbance values at 1525 cm−1 for Mancozeb and 2070 cm−1 for KSCN. In these conditions a precision as relative standard deviation (RSD) of 0.6% and a relative accuracy error of 0.8% (w/w) were found. For complex formulations, containing other compounds with characteristic ab…

Synthesis and Physical Stability of Novel Au-Ag@SiO<SUB>2</SUB> Alloy Nanoparticles

2012

The present study describes the synthesis of nanoparticles of silver-gold alloys and with their electrokinetic and spectroscopic characterisation. The synthesis was made in two steps. In the first step silver nanoparticles coated with silica (Ag@SiO2) were synthesised using a novel method assisted by laser ablation. The second step consisted on the introduction of KAuCl4 in the colloidal solution of Ag@ SiO2 nanoparticles in order to obtain silica-coated silver-gold alloy nanoparticles. The changes of colour and mean diameter of Ag@SiO2 nanoparticles caused by the introduction of the gold salt were found dependent on its concentration. Upon increasing (KAuCl4) the diameter of nanoparticles …