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151.
Aurelian Gulea Donald Poirier Jenny Roy Vitalie Stavila Ion Bulimestru Victor Tapcov 《Journal of enzyme inhibition and medicinal chemistry》2013,28(6):806-818
The present paper describes the synthesis, characterization and in vitro biological evaluation screening of different classes (ammoniacates, dioximates, carboxylates, semi- and thiosemicarbazidates) of Co(II), Co(III), Cu(II), Ni(II), Mn(II), Zn(II) and Fe(III) complexes. Schiff bases were obtained from the reaction of some salicyl aldehydes with, respectively, furoylhydrazine, benzoylhydrazine, semicarbazide, thiosemicarbazide and S-methylthiosemicarbazide to give tridentate ligands containing ONO, ONS or ONN as donor atoms. The synthetic metal complexes are of various geometrical and electronic structures, thermodynamic and thermal stabilities, and magnetic and conductance properties. All complexes, except those of Cu, are octahedral. Some Cu, Co and Mn compounds have a dimeric or a polymeric structure. The composition and structure of complexes were analysed by elemental analysis, IR and 1H NMR and 13C NMR spectroscopies, and magnetochemical, thermoanalytical and molar conductance measurements. All ligands and metal complexes were tested as inhibitors of human leukemia (HL-60) cells growth, and the most potent, the Cu(II) complexes, have been also tested for their in vitro antibacterial and antifungal activities. Structure-activity relationships were carried out. 相似文献
152.
David Shum Constantin Radu Earl Kim Muriel Cajuste Yufang Shao Venkatraman E. Seshan 《Journal of enzyme inhibition and medicinal chemistry》2013,28(6):931-945
In response to the need for inexpensive high throughput assays for anti-cancer drug screening, a 1536-well microtiter plate based assay utilizing the Alamar Blue fluorescent dye as a measure of cellular growth was validated in 10 μL assay volume. Its robustness was assessed in a screen against a library of 2000 known bioactives; with an overall Z′ value of 0.89 for assay robustness, several known cytotoxic agents were identified including and not limited to anthracyclines, cardiac glycosides, gamboges, and quinones. To further test the sensitivity of the assay, IC50 determinations were performed in both 384-well and 1536-well formats and the obtained results show a very good correlation between the two density formats. These findings demonstrate that this newly developed assay is simple to set up, robust, highly sensitive and inexpensive. It could potentially provide a rapid way to screen established and primary tumor cell lines against large chemical libraries. 相似文献
153.
Lee HY Chai LC Pui CF Wong WC Mustafa S Cheah YK Mat Issa Z Nishibuchi M Radu S 《Journal of microbiology and biotechnology》2011,21(9):954-959
There have been a number of studies conducted in order to compare the efficiencies of recovery rates, utilizing different protocols, for the isolation of L. monocytogenes. However, the severity of multiple cell injury has not been included in these studies. In the current study, L. monocytogenes ATCC 19112 was injured by exposure to extreme temperatures (60°C and -20°C) for a one-step injury, and for a two-step injury the cells were transferred directly from a heat treatment to frozen state to induce a severe cell injury (up to 100% injury). The injured cells were then subjected to the US Food and Drug Administration (FDA), the ISO-11290, and the modified United States Department of Agriculture (mUSDA) protocols, and plated on TSAyeast (0.6% yeast), PALCAM agar, and CHROMAgar Listeria for 24 h or 48 h. The evaluation of the total recovery of injured cells was also calculated based on the costs involved in the preparation of media for each protocol. Results indicate that the mUSDA method is best able to aid the recovery of heat-injured, freeze-injured, and heat-freeze-injured cells and was shown to be the most cost effective for heat-freeze-injured cells. 相似文献
154.
Olusesan AT Azura LK Abubakar F Mohamed AK Radu S Manap MY Saari N 《Journal of molecular microbiology and biotechnology》2011,20(2):105-115
Bacillus strain NS 8, a lipase-producing bacterium isolated from a Malaysian hot spring, is able to tolerate a broad range of temperature and pH, which makes it beneficial for this study. It generated PCR products with molecular weight of 1,532 bp, and the 16S rRNA sequence analysis identified it as Bacillus subtilis with accession number AB110598. It showed a 71% similarity index with B. subtilis using Biolog Microstation System. Its lipase production was optimized using a shake flask system by changing the physical (agitation speed, pH and temperature) and nutritional (nitrogen, carbon and minerals) factors. The most suitable combination of the basal medium for lipase production was 2.5% olive oil (carbon), 1.5% peptone (nitrogen), 0.1% MgSO(4) (mineral) at an optimum temperature of 50°C, pH 7.5 and 150 rpm agitation, giving an enzyme yield of 4.23 U/ml. Statistical optimization using response surface methodology was carried out. An optimum lipase production of 5.67 U/ml was achieved when olive oil concentration of 3%, peptone 2%, MgSO(4)·7H(2)O 0.2% and an agitation rate of 200 rpm were combined. Lipase production was further carried out inside a 2-liter bioreactor, which yielded an enzyme activity of 14.5 U/ml after 15 h of incubation. 相似文献
155.
Patwari P Emilsson V Schadt EE Chutkow WA Lee S Marsili A Zhang Y Dobrin R Cohen DE Larsen PR Zavacki AM Fong LG Young SG Lee RT 《Cell metabolism》2011,14(5):671-683
A human genome-wide linkage scan for obesity identified a linkage peak on chromosome 5q13-15. Positional cloning revealed an association of a rare haplotype to high body-mass index (BMI) in males but not?females. The risk locus contains a single gene, "arrestin domain-containing 3" (ARRDC3), an uncharacterized α-arrestin. Inactivating Arrdc3 in mice led to a striking resistance to obesity, with greater impact on male mice. Mice with decreased ARRDC3 levels were protected from obesity due to increased energy expenditure through increased activity levels and increased thermogenesis of both brown and white adipose tissues. ARRDC3 interacted directly with β-adrenergic receptors, and loss of ARRDC3 increased the response to β-adrenergic stimulation in isolated adipose tissue. These results demonstrate that ARRDC3 is a gender-sensitive regulator of obesity and energy expenditure and reveal?a surprising diversity for arrestin family protein functions. 相似文献
156.
Zolog O Mot A Deac F Roman A Fischer-Fodor E Silaghi-Dumitrescu R 《The protein journal》2011,30(1):27-31
A new protocol is described for derivatization of hemoglobin with polyethyleneglycol (PEG) via reaction of the unmodified
native hemoglobin with an activated amine-reacting polyethylene glycol derivative which, unlike protocols previously described,
leads to formation of a peptide bond between hemoglobin and PEG. Dioxygen binding and peroxide reactivities of the derivatized
hemoglobin are examined, and found to be within reasonable limits, with the particular observation that, unlike with a few
other derivatization protocols, the dioxygen affinity is slightly lower than that of native Hb. In cell culture tests (human
umbilical vein epithelial cells, HUVEC), the derivatization protocol induces no toxic effect. These results show promise towards
applicability for production of hemoglobin-based blood substitutes. 相似文献
157.
SH2 domains are interaction modules uniquely dedicated to recognize phosphotyrosine sites, playing a central role in for instance
the activation of tyrosine kinases or phosphatases. Here we report the 1H, 15N and 13C backbone and side-chain chemical shift assignments of the SH2 domain of the human protein tyrosine kinase Fyn, both in its
free state and bound to a high-affinity phosphotyrosine peptide corresponding to a specific sequence in the hamster middle-T
antigen. The BMRB accession numbers are 17,368 and 17,369, respectively. 相似文献
158.
159.
160.
Wen Hui Li Wan Zhong Jia Zi Gang Qu Zhi Zhou Xie Jian Xun Luo Hong Yin Xiao Lin Sun Radu Blaga Bao Quan Fu 《The Korean journal of parasitology》2013,51(2):197-201
A total of 16 Taenia multiceps isolates collected from naturally infected sheep or goats in Gansu Province, China were characterized by sequences of mitochondrial cytochrome c oxidase subunit 1 (cox1) gene. The complete cox1 gene was amplified for individual T. multiceps isolates by PCR, ligated to pMD18T vector, and sequenced. Sequence analysis indicated that out of 16 T. multiceps isolates 10 unique cox1 gene sequences of 1,623 bp were obtained with sequence variation of 0.12-0.68%. The results showed that the cox1 gene sequences were highly conserved among the examined T. multiceps isolates. However, they were quite different from those of the other Taenia species. Phylogenetic analysis based on complete cox1 gene sequences revealed that T. multiceps isolates were composed of 3 genotypes and distinguished from the other Taenia species. 相似文献