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11.
Molecular and Cellular Biochemistry - The protective activity of N-(2-hydroxyphenyl)acetamide (NA-2) and NA-2-coated gold nanoparticles (NA-2-AuNPs) in glycerol-treated model of acute kidney injury...  相似文献   
12.
There is a high incidence of oral squamous cell carcinoma (SCC) worldwide. The survival rate is among the lowest of the major cancers and has not improved significantly over the past two decades. The KB line of human oral carcinoma cells is a useful experimental system for studies of the biology of oral SCC. In a previous study, we reported inhibition of KB cell proliferation and stimulation of desmosome formation in confluent cultures treated with 20 microM H-7 (1-(5-isoquinolinylsulfonyl)-2-methylpiperazine). In the present study, the effects of this protein kinase C (PKC) inhibitor on the survival of KB cells were investigated. Apoptotic cells were detected using a combination of Hoechst 33258 nuclear stain, TUNEL technique and ultrastructural analysis. Our results indicated that H-7 significantly increased apoptosis in KB cells in a dose-dependent manner. Maximal stimulation occurred at 100 microM, the highest dose of H-7 tested. Apoptotic cells exhibited nuclear fragmentation, chromatin condensation and apoptotic bodies. Interestingly, H-7 and fetal calf serum (FCS) acted synergistically to increase apoptosis in KB cells, suggesting that there is a serum activated subpopulation of H-7 target cells in the cultures. The underlying mechanism of activation remains to be elucidated. Our study suggests that the PKC inhibitor H-7 is a potentially useful cytostatic agent for oral carcinoma cells.  相似文献   
13.
A rapid, simple, accurate and highly sensitive spectrofluorimetric method was developed for the simultaneous analysis of nebivolol hydrochloride (NEB) and amlodipine besylate (AML). The method was based on measuring the synchronous fluorescence intensity of the drugs at Δλ = 40 nm in methanol. Various experimental parameters affecting the synchronous fluorescence of the studied drugs were carefully studied and optimized. The calibration plots were rectilinear over concentration ranges of 0.05–1.5 µg/mL and 0.5–10 µg/mL for NEB and AML with limits of detection (LOD) of 0.010 and 0.051 µg/mL and limits of quantitation (LOQ) of 0.031 and 0.156, respectively. The peak amplitudes (2D) of the second derivative synchronous fluorimetry (SDSF) were estimated at 282 nm for NEB and at 393 nm for AML. Good linearity was obtained over the concentration ranges. The proposed method was successfully applied to the determination of the studied compounds in laboratory‐prepared mixtures, commercial single and laboratory‐prepared tablets. The results were in good agreement with those obtained using the comparison method. The mean percent recoveries were found to be 100.12 ± 0.77 and 99.91 ± 0.77 for NEB and AML, respectively. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
14.
Seven 9,10-seco-9,19-cyclolanostane arabinosides, named podocarpasides A-G (1-7), were isolated from the roots of Actaea podocarpa DC., a species closely related to black cohosh (a well known dietary supplement). Their structures were determined with the help of spectroscopic data including extensive 2D NMR spectroscopy. The isolates were found inactive, when tested for cytotoxic, estrogenic, and antioxidant activities in cell based assays. They were also tested for anticomplement activity against the classical pathway of complement system and only podocarpaside C (3) inhibited modest complement activity with an IC50 value of 200 microM.  相似文献   
15.
We have studied DNA sequence variation in and around the genes ICAM1 and TNF, which play functional and correlated roles in inflammatory processes and immune cell responses, in 12 diverse ethnic groups of India, with a view to investigating the relative roles of demographic history and natural selection in shaping the observed patterns of variation. The total numbers of single nucleotide polymorphisms (SNPs) detected at the ICAM1 and TNF loci were 29 and 12, respectively. Haplotype and allele frequencies differed significantly across populations. The site frequency spectra at these loci were significantly different from those expected under neutrality, and showed an excess of intermediate-frequency variants consistent with balancing selection. However, as expected under balancing selection, there was no significant reduction of F ST values compared to neutral autosomal loci. Mismatch distributions were consistent with population expansion for both loci. On the other hand, the phylogenetic network among haplotypes for the TNF locus was similar to expectations under population expansion, while that for the ICAM1 was as expected under balancing selection. Nucleotide diversity at the ICAM1 locus was an order of magnitude lower in the promoter region, compared to the introns or exons, but no such difference was noted for the TNF gene. Thus, we conclude that the pattern of nucleotide variation in these genes has been modulated by both demographic history and selection. This is not surprising in view of the known allelic associations of several polymorphisms in these genes with various diseases, both infectious and noninfectious.  相似文献   
16.
We report the synthesis, in vitro antiprotozoal (against Plasmodium and Leishmania), antimicrobial, cytotoxicity (Vero and MetHb-producing properties), and in vivo antimalarial activities of two series of 8-quinolinamines. N1-{4-[2-(tert-Butyl)-6-methoxy-8-quinolylamino]pentyl}-(2S/2R)-2-aminosubstitutedamides (21-33) and N1-[4-(4-ethyl-6-methoxy-5-pentyloxy-8-quinolylamino)pentyl]-(2S/2R)-2-aminosubstitutedamides (51-63) were synthesized in six steps from 6-methoxy-8-nitroquinoline and 4-methoxy-2-nitro-5-pentyloxyaniline, respectively. Several analogs displayed promising antimalarial activity in vitro against Plasmodium falciparum D6 (chloroquine-sensitive) and W2 (chloroquine-resistant) clones with high selectivity indices versus mammalian cells. The most promising analogs (21-24) also displayed potent antimalarial activity in vivo in a Plasmodium berghei-infected mouse model. Most interestingly, many analogs exhibited promising in vitro antileishmanial activity against Leishmania donovani promastigotes, and antimicrobial activities against a panel of pathogenic bacteria and fungi. Several analogs, notably 21-24, 26-32, and 60, showed less MetHb formation compared to primaquine indicating the potential of these compounds in 8-quinolinamine-based antimalarial drug development.  相似文献   
17.
The biochemical pathways followed by a mixed bacterial culture and one of its constituent strains, Sarcina maxima, MTCC 5216 (hitherto unreported) during the degradation of mononitrophenol isomers was studied using extensive nuclear magnetic resonance (NMR) spectroscopy (One- and Two-Dimensional Heteronuclear Multiple Quantum Coherence Transfer-2D HMQCT NMR). NMR investigations revealed that o-nitrophenol (ONP) could be degraded by the consortium to metabolites such as catechol, cis, cis-muconic acid, γ-hydroxymuconic semialdehyde, maleylacetate and β-ketoadipate. The spectra of ONP reaction mixture degraded by S.␣maxima showed that formation of maleylacetate from γ-hydroxymuconic semialdehyde should go through a new metabolite γ-hydroxymaleylacetate, hitherto unreported. The consortium could breakdown m-nitrophenol (MNP) to 4-aminocatechol indicating that it came from 3-hydroxyaminophenol. However, S. maxima MTCC 5216, could convert MNP to hitherto unreported 2-nitrohydroquinone and the subsequent 2-hydroxylaminohydroquinone to 1,2,4-benzenetriol along with γ-hydroxymuconic semialdehyde, muconolactone and maleylacetate. The pathway followed by the consortium during p-nitrophenol (PNP) degradation was by the formation of 4-nitrocatechol, maleylacetate and β-ketoadipate. PNP reaction mixture of S.␣maxima, MTCC 5216 on the other hand, showed that the pathway could proceed through the formation of p-hydroquinone as the initial metabolite. The present study conclusively established the nitrophenol-degrading ability of both the consortium and S. maxima MTCC 5216, including exhibiting slight deviations from the pathways followed by the other reported microorganisms.  相似文献   
18.
Isosteres of cryptolepine (1) were synthesized and evaluated for their antiinfective activities. Overall, the sulfur isostere, 5-methyl benzothieno[3,2-b]quinolinium salt (5b), was equipotent to 1 and has shown no cytotoxicity at 23.8 microg/mL. Compound 5b was also found to have a broad spectrum of activity. Both the carbon and oxygen isosteres were less potent than cryptolepine. A limited library of 2-substituted analogs of 5b has been synthesized and evaluated in antifungal screens but did not show increase in potency compared to the unsubstituted 5b. Similarly, evaluation of tricyclic benzothieno[3,2-b]pyridines while showing promise in individual screens did not produce an overall increase in potency. Overall, the evaluation of the activities of 5b compared with standard antifungal/anti-protozoal agents suggests that the benzothienoquinoline scaffold could serve as a lead for optimization.  相似文献   
19.
Human cardiac progenitor cells (hCPC) improve heart function after autologous transfer in heart failure patients. Regenerative potential of hCPCs is severely limited with age, requiring genetic modification to enhance therapeutic potential. A legacy of work from our laboratory with Pim1 kinase reveals effects on proliferation, survival, metabolism, and rejuvenation of hCPCs in vitro and in vivo. We demonstrate that subcellular targeting of Pim1 bolsters the distinct cardioprotective effects of this kinase in hCPCs to increase proliferation and survival, and antagonize cellular senescence. Adult hCPCs isolated from patients undergoing left ventricular assist device implantation were engineered to overexpress Pim1 throughout the cell (PimWT) or targeted to either mitochondrial (Mito-Pim1) or nuclear (Nuc-Pim1) compartments. Nuc-Pim1 enhances stem cell youthfulness associated with decreased senescence-associated β-galactosidase activity, preserved telomere length, reduced expression of p16 and p53, and up-regulation of nucleostemin relative to PimWT hCPCs. Alternately, Mito-Pim1 enhances survival by increasing expression of Bcl-2 and Bcl-XL and decreasing cell death after H2O2 treatment, thereby preserving mitochondrial integrity superior to PimWT. Mito-Pim1 increases the proliferation rate by up-regulation of cell cycle modulators Cyclin D, CDK4, and phospho-Rb. Optimal stem cell traits such as proliferation, survival, and increased youthful properties of aged hCPCs are enhanced after targeted Pim1 localization to mitochondrial or nuclear compartments. Targeted Pim1 overexpression in hCPCs allows for selection of the desired phenotypic properties to overcome patient variability and improve specific stem cell characteristics.  相似文献   
20.
Previous studies on the indoloquinoline alkaloid, cryptolepine (2), revealed that it has antii-nfective properties among other activities. Using Structure-activity relationship (SAR) techniques, several ring-opened analogs of cryptolepine (3-phenylaminopyridinium and 3-phenylaminoquinolinium derivatives) were designed to improve the potency and lower the cytotoxicity shown by several of the precursor agents. Results indicate that these ring-opened analogs constitute new anti-infective agents with over a 100-fold potency and several fold lower cytotoxicity than cryptolepine from which they are derived.  相似文献   
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