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161.
Secondary acquired mutant EGFR (L858R-T790M) overexpressed NSCLC forms one of the prevalent form of resistant NSCLC. Another subset of resistant NSCLC includes amplified cMET in mutant EGFR derived tumours. Thus, in continuation to our previous work on these two major targets of resistant NSCLC, i.e., EGFR (L858R-T790M) and cMET, we are hereby reporting reversible inhibitors of these kinases. Out of 11 lead molecules reported in our previous study, we selected triazolo-pyrimidone (BAS 09867482) scaffold for further development of small molecule dual and reversible inhibitors. Analogues of lead with different substituents on the side ring were sketched and docked in both the target kinases, followed by molecular dynamic simulations. Analogues maintaining hydrophobic interaction with M790 in secondary acquired mutant EGFR (L858R-T790M) were selected and duly synthesized. In vitro biochemical evaluation of these molecules against EGFR (L858R-T790M) and cMET kinase, along with EGFR (L858R) kinase disclosed that three molecules were having significant dual kinase inhibitory potential with IC50 values well below 100 nM. Further, in vitro anti-proliferative assay against three cell lines (A549, A431 and H460) was performed. Out of all, two compounds were having significant potency against these cell lines.  相似文献   
162.
中国的炭疽杆菌DNA分型及其地理分布   总被引:6,自引:1,他引:6  
炭疽广泛分布于中国各地,特别是西部地区,并经常造成人畜疾病,在一项合作研究中,用多位点VNTR分析(MLVA)对从1952-1998年自中国主要地理流行区域分离的病人,病畜和土壤等来源的炭疽杆菌进行了基因分型,MLVA分析结果揭示了21种新的基因型,其等位基因组合在以前世界范围分离物的研究中未曾发现,此外,分离物的分群显示,A3b组是地理上最广泛分布的基因组,说明该组可能是中国的“地方流行株”。而来自古丝绸之路重要贸易中心新疆的大量分离株其基因型特别分散。  相似文献   
163.
 细菌(Pseudomonas moltophilia)与hCG及LH有特异的亲和力,实验发现,细菌之生长曲线与hCG结合活性成平行关系,96小时达高峰,细菌之培养液中含有可溶性结合蛋白,该蛋白经硫酸铵沉淀(80%饱和度)、Sephadex G-100柱层析、DEAE-纤维素柱0.5mol/L NaCl梯度洗脱,再过Sepharose CL-AB柱,收集之活性部分经SDS电泳测得其分子量为70,000,凝胶层析测Stokes radius为41A,Schiff氏染色未见着色带。  相似文献   
164.
Buoyant density in CsCl, melting temperature, and G + C base content of the DNA from four species of Akodon (Rodentia, Cricetidae) were determined. The buoyant density values of 1.699–1.701 g/cm3 were in accordance with the data reported for other cricetids. No satellite bands were seen in neutral CsCl. The T m values determined in 1 × SSC ranged from 86.2 to 87.0 C, which corresponds to G + C contents of 41.2–43.2%. There was good agreement in DNA base composition of the four species, although values were slightly higher in A. obscurus, suggesting a certain degree of interspecies variability.This study was supported by grants from Comisión de Investigaciones Científicas de la Provincia de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, and Organización de Estados Americanos.  相似文献   
165.
Large lipid transfer proteins (LLTP) are nonexchangeable apolipoproteins and intracellular lipid-exchange proteins involved in the assembly, secretion, and metabolism of lipoproteins. We have identified contiguous conserved sequence motifs in alignments of insect apolipophorin II/I precursor (apoLp-II/I), human apolipoprotein B (apoB), invertebrate and vertebrate vitellogenins (VTG), and the large subunit of mammalian microsomal triglyceride transfer protein (MTP). Conserved motifs present in the N-terminal part of nonexchangeable apolipoproteins encompass almost completely the large subunit of MTP, suggesting a derivation from a common ancestral functional unit, termed large lipid transfer (LLT) module. Divergence of LLTP from a common ancestor is supported by (1) the statistical significance of the combined match scores obtained after motif-based database searches, (2) the presence of several identical amino acid residues in all LLTP sequences currently available, (3) the conservation of hydrophobic clusters in an α-helical domain, (4) the phylogenetic analysis of the conserved sequences related to the von Willebrand factor D (VWD) module identified in nonexchangeable apolipoproteins, and (5) the presence of four and one ancestral exon boundaries in the LLT and VWD modules, respectively. Our data indicate that the genes coding for apoLp-II/I, apoB, VTG, and the MTP large subunit are members of the same multigene superfamily. LLTP have emerged from an ancestral molecule designed to ensure a pivotal event in the intracellular and extracellular transfer of lipids and liposoluble substances. Received: 8 June 1998 / Accepted: 15 February 1999  相似文献   
166.
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168.
Viral infectivity factor (Vif) is one of the accessory protein of human immunodeficiency virus type I (HIV-1) that inhibits host defense factor, APOBEC3G (A3G), mediated viral cDNA hypermutations. Previous work developed a novel Vif inhibitor 2-amino-N-(2-methoxyphenyl)-6-((4-nitrophenyl)thio)benzamide (1) with strong antiviral activity. Through optimizations on the two side branches, a series of compound 1 derivatives (218) were designed, synthesized and tested in vitro for their antiviral activities. The biological results showed that compound 5 and 16 inhibited the virus replication efficiently with EC50 values of 9.81 and 4.62 μM. Meanwhile, low cytotoxicities on H9 cells were observed for the generated compounds by the MTT assay. The structure–activity relationship of compound 1 was preliminarily clarified, which gave rise to the development of more potent Vif inhibitors.  相似文献   
169.
A series of thirty (30) thiazole analogs were prepared, characterized by 1H NMR, 13C NMR and EI-MS and evaluated for Acetylcholinesterase and butyrylcholinesterase inhibitory potential. All analogs exhibited varied butyrylcholinesterase inhibitory activity with IC50 value ranging between 1.59 ± 0.01 and 389.25 ± 1.75 μM when compared with the standard eserine (IC50, 0.85 ± 0.0001 μM). Analogs 15, 7, 12, 9, 14, 1, 30 with IC50 values 1.59 ± 0.01, 1.77 ± 0.01, 6.21 ± 0.01, 7.56 ± 0.01, 8.46 ± 0.01, 14.81 ± 0.32 and 16.54 ± 0.21 μM respectively showed excellent inhibitory potential. Seven analogs 15, 20, 19, 24, 28, 30 and 25 exhibited good acetylcholinesterase inhibitory potential with IC50 values 21.3 ± 0.50, 35.3 ± 0.64, 36.6 ± 0.70, 44.81 ± 0.81, 46.36 ± 0.84, 48.2 ± 0.06 and 48.72 ± 0.91 μM respectively. All other analogs also exhibited well to moderate enzyme inhibition. The binding mode of these compounds was confirmed through molecular docking.  相似文献   
170.
In the present study, the nucleotide sequences of the CHS1 gene from dermatophytes and related fungi in the genera Chrysosporium, Epidermophyton, Microsporum and Trichophyton were investigated using molecular methods. About 440-bp genomic DNA fragments of the CHS1 gene from 21 species were amplified by polymerase chain reaction (PCR) and sequenced. The CHS1 nucleotide sequences of these fungi showed more than 83% similarity. The molecular taxonomy of the CHS1 gene sequences revealed that Microsporum was genetically distinct from Chrysosporium and Trichophyton, as classified by morphological characteristics. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
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