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991.
Abdull Razis AF Ismail EN Hambali Z Abdullah MN Ali AM Mohd Lila MA 《Applied biochemistry and biotechnology》2008,144(3):249-261
Recombinant human epidermal growth factor (EGF) was successfully expressed as a fusion protein in Escherichia coli system. This system was used OmpA signal sequence to produce soluble protein into the periplasm of E. coli. Human EGF (hEGF) synthesized in bacterial cell was found to be similar in size with the original protein and molecular weight
approximately at 6.8 kDa. Cell proliferation assay was conducted to characterize the biological activity of hEGF on human
dermal fibroblasts. The synthesized hEGF was found to be functional as compared with authentic hEGF in stimulating cell proliferation
and promoting growth of cell. In comparison of biological activity between synthesized and commercial hEGF on cell proliferation,
the results showed there was no significant different. This finding indicates the synthesized hEGF in E. coli system is fully bioactive in vitro. 相似文献
992.
The interaction of DNA with Copper(II)-Glutathione (CuGSH) has been investigated by various biophysical methods. The interaction
ratio of DNA and Copper(II)-Glutathione in solution phase has been determined spectrophotometrically and found to be 0.25.
EPR spectroscopy and UV–Vis findings suggest that Cu(II)-Glutathione neither bound to the DNA bases covalently nor intercalated,
this has further been substantiated by the determination of intrinsic binding constant (2.1 × 102). Viscometric measurements also support this type of binding to DNA by Cu(II)-Glutathione. EPR studies and visible d–d spectra
of CuGSH after interaction with DNA, suggested that Copper remained in the Copper(II) state. DNA conformations after interaction
with Cu(II)-Glutathione has been determined spectroscopically. Circular dichroism studies revealed that the B conformation
of DNA is changed to A after interaction with Cu(II)-Glutathione. This has further been substantiated by thin film IR (Infrared)
studies. 相似文献
993.
Yum JH Jang SR Humphry-Baker R Grätzel M Cid JJ Torres T Nazeeruddin MK 《Langmuir : the ACS journal of surfaces and colloids》2008,24(10):5636-5640
The effect of chenodeoxycholic acid as a coadsorbent on TiO 2 nanocrystalline solar cells incorporating phthalocyanine sensitizers was studied under various conditions. Adding chenodeoxycholic acid onto TiO 2 nanoparticles not only reduces the adsorption of phthalocyanine sensitizers but also prevents sensitizer aggregation, leading to different photovoltaic performance. The inspection of IPCE and absorption spectra showed that the load of phthalocyanine sensitizers is strongly dependent on the molar concentration of chenodeoxycholic acid coadsorbent. The open circuit voltage of the solar cells with chenodeoxycholic acid coadsorbent increases due to the enhanced electron lifetime in TiO 2 nanoparticles coupled with the band edge shift of TiO 2 to negative potentials. 相似文献
994.
Bessho T Constable EC Graetzel M Hernandez Redondo A Housecroft CE Kylberg W Nazeeruddin MK Neuburger M Schaffner S 《Chemical communications (Cambridge, England)》2008,(32):3717-3719
Dye-sensitized solar cells with carboxylate-derivatized {Cu(I)L(2)} complexes are surprisingly efficient and offer a long-term alternative approach to ruthenium-functionalized systems. 相似文献
995.
Low surface coverage of Au nanoparticles on an indium tin oxide electrode for sensitive electrochemical detection was achieved using electrostatic adsorption of AuCl(4)(-) followed by reduction. 相似文献
996.
997.
Reddy SL Fayazuddin M Reddy NC Ahmad A Reddy GS Rao PS Reddy BJ Frost RL 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2008,71(1):31-38
Leaves of bhringaraj and guduchi herb of Kadapa district of Andhra Pradesh, India, are dried and powdered. ICP-MS analysis of samples indicates that copper is present in both the samples. An EPR study of guduchi sample also confirms the presence of Fe(III) whereas Eclipta alba confirms the presence of Fe(III), Mn(II) and Cu(II). Optical absorption spectrum of guduchi indicates that Cu(II) is present in rhombically distorted octahedral environment. NIR and IR results are due to carbonate fundamentals. 相似文献
998.
Tributyltin hydride-mediated radical reactions of organic halides were successfully carried out in a continuous flow system using a microreactor. The reactions proceeded within a very short period of time, coupled with quickly decomposing radical initiators such as V-65 and V-70. The continuous flow reaction system was applied to gram scale synthesis of a key intermediate for furofuran lignans. 相似文献
999.
Sporty JL Kabir MM Turteltaub KW Ognibene T Lin SJ Bench G 《Journal of separation science》2008,31(18):3202-3211
A robust redox extraction protocol for quantitative and reproducible metabolite isolation and recovery has been developed for simultaneous measurement of nicotinamide adenine dinucleotide (NAD) and its reduced form, NADH, from Saccharomyces cerevisiae. Following culture in liquid media, yeast cells were harvested by centrifugation and then lysed under nonoxidizing conditions by bead blasting in ice-cold, nitrogen-saturated 50 mM ammonium acetate. To enable protein denaturation, ice cold nitrogen-saturated CH(3)CN/50 mM ammonium acetate (3:1 v/v) was added to the cell lysates. Chloroform extractions were performed on supernatants to remove organic solvent. Samples were lyophilized and resuspended in 50 mM ammonium acetate. NAD and NADH were separated by HPLC and quantified using UV-Vis absorbance detection. NAD and NADH levels were evaluated in yeast grown under normal (2% glucose) and calorie restricted (0.5% glucose) conditions. Results demonstrate that it is possible to perform a single preparation to reliably and robustly quantitate both NAD and NADH contents in the same sample. Robustness of the protocol suggests it will be (i) applicable to quantification of these metabolites in other cell cultures; and (ii) amenable to isotope labeling strategies to determine the relative contribution of specific metabolic pathways to total NAD and NADH levels in cell cultures. 相似文献
1000.
Shahid H. Naikoo Haroon Rashid Ragni Gupta Raghu Rai Sharma Sanjay Kumar Riyaz Ahmad Satish Gudup Parvinder P. Singh Sheikh Tasduq Abdullah 《Photochemistry and photobiology》2023,99(5):1343-1351
Ultraviolet radiation (UVR) is the major exogenous agent that disturbs tissue homeostasis and hastens the onset of age-related phenotypes (photoaging). Exposure to UV-B radiation promotes apoptosis in human skin cells via induction of Reactive Oxygen Species (ROS)-mediated Endoplasmic Reticulum (ER) stress by activating the PERK-eIF2α-CHOP pathway, which plays a major role in exacerbating skin photoaging. Alleviating the production of ROS and boosting the antioxidant capacity of cells is the foremost therapeutic strategy to avert the repercussions of ultraviolet radiation exposure. In this study, we investigated the role of 3-(1′-methyltetrahydropyridinyl)-2,4-6-trihydroxy acetophenone (IIIM-8) in thwarting the UV-B-induced photoaging. We observed that IIIM-8 ameliorates UV-B-induced oxidative stress, ER stress, Loss of Mitochondrial membrane potential, MAPK activation and Inflammation in irradiated skin cells. Ultraviolet radiation-related damage to fibroblasts within the dermis leads to collagen degradation-the hallmark of photoaging. IIIM-8 substantially restored the synthesis of collagen and prevented its degradation via the downregulation of matrix metalloproteinases. Topical application of IIIM-8 prevented BALB/c mice skin from UV-B-induced leukocyte infiltration, epidermal thickening and disruption of Extracellular matrix components. Implying that IIIM-8 has a strong photoprotective property and has potential to be developed as a topical therapeutic/cosmeceutical agent against UV-B-induced photoaging. 相似文献