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141.
The rhizomes of Homalomena occulta are called Qian-nian-jian in Traditional Chinese Medicine (TCM), which is widely consumed in China owing to its health benefits for the treatment of rheumatoid arthritis and for strengthening tendons and bones. A phytochemical investigation on this famous TCM yielded 19 sesquiterpenoids (119) with various carbocyclic skeletons including isodaucane (2, 8, and 9), guaiane (3), eudesmane (4 and 1015), oppositane (5, 16, and 17), and aromadendrane (18 and 19) types. The structures of new compounds, Homalomenins A-E (15), were determined by diverse spectroscopic data. Compound 1 possessed a rare sesquiterpenoid skeleton and compound 5 represented the first example of 1,4-oxa-oppositane sesquiterpenoid. These isolates were evaluated for their inhibitory effects on COX-2 mRNA, COX-2 protein expression, and prostaglandin E2 (PGE2) production in Raw264.7 cells, which demonstrated that compounds 5, 18, 19 showed potent anti-inflammatory activity by suppressing LPS-induced COX-2 expression and PGE2 production in a dose-dependent manner.  相似文献   
142.
On two tests of fit for HLA data with no double blanks.   总被引:1,自引:1,他引:1       下载免费PDF全文
Stevens suggests a test of fit, based on Bernstein's estimators, of the Hardy-Weinberg law for the ABO system. Nam and Gart extend this test to the generalized ABO-like system and apply it to HLA data. When the recessive gene is rare, Huether and Murphy recall Haldane's point that its Bernstein's estimator is negatively biased and go on to suggest novel corrected versions of it. With the identification of more HLA antigens, it is not uncommon to find, in certain populations, that the sample data contain no double blanks; that is, every individual reacts to at least one antigen for a given locus. Gart and Nam give a simple score test of a zero true recessive-gene frequency for such situations. Here we examine the extended test of Stevens as a test of this hypothesis. We find that it is fully efficient for two codominant alleles but that when the number exceeds two its efficiency may be 50% or lower or as high as 100%, depending on the number of alleles and the pattern of gene frequencies. The tests are applied to a set of HLA data.  相似文献   
143.
The damage incurred in osteoarthritis (OA) is mediated by a variety of cytokines, growth factors and inflammatory mediators. The importance of the interleukin-17 (IL-17) family in inflammatory and autoimmune disease is becoming increasingly apparent. Microsatellite association mapping reveals a primary osteoarthritis susceptibility locus on chromosome 6p12.3-q13. IL-17A and IL-17F genes that resided on chromosome 6p12.3-q13 are believed to play an important role in the primary OA susceptibility. We investigated the allele and genotype of IL-17A G-197A and IL-17F T7488C in 302 OA patients and 300 healthy subjects as controls. We employed a PCR-SSCP assay to identify the genotypes IL-17A G-197A and IL-17F T7488C. For IL-17A G-197A, there were significant differences in frequencies of genotype and allele of IL-17A G-197A between OA patients and controls (both p < 0.0001). For IL-17F T7488C, there were no significant differences in the allele frequency and genotype distribution for IL-17F T7488C between OA patients and controls (p = 0.938 and p = 0.1735, respectively). In conclusion, current study showed that polymorphism of IL-17A G-197A may be closely associated with susceptibility to the development of OA in the Korean population. However, there was no relationship between IL-17F T7488C polymorphism and OA susceptibility.  相似文献   
144.
Matrix metalloproteinases (MMPs) are extracellular matrix (ECM) degrading enzymes and have complex and specific regulation networks. This includes activation interactions, where one MMP family member activates another. ECM degradation and MMP activation can be initiated by several different stimuli including changes in ECM mechanical properties or intracellular contractility. These mechanical stimuli are known enhancers of metastatic potential. MMP-14 facilitates local ECM degradation and is well known as a major mediator of cell migration, angiogenesis and invasion. Recently, function blocking antibodies have been developed to specifically block MMP-14, providing a useful tool for research as well as therapeutic applications. Here we utilize a selective MMP-14 function blocking antibody to delineate the role of MMP-14 as an activator of other MMPs in response to changes in cellular contractility and ECM stiffness. Inhibition using function blocking antibodies reveals that MMP-14 activates soluble MMPs like MMP-2 and -9 under various mechanical stimuli in the pancreatic cancer cell line, Panc-1. In addition, inhibition of MMP-14 abates Panc-1 cell extension into 3D gels to levels seen with non-specific pan-MMP inhibitors at higher concentrations. This strengthens the case for MMP function blocking antibodies as more potent and specific MMP inhibition therapeutics.  相似文献   
145.
High‐capacity Li‐rich layered oxide cathodes along with Si‐incorporated graphite anodes have high reversible capacity, outperforming the electrode materials used in existing commercial products. Hence, they are potential candidates for the development of high‐energy‐density lithium‐ion batteries (LIBs). However, structural degradation induced by loss of interfacial stability is a roadblock to their practical use. Here, the use of malonic acid‐decorated fullerene (MA‐C60) with superoxide dismutase activity and water scavenging capability as an electrolyte additive to overcome the structural instability of high‐capacity electrodes that hampers the battery quality is reported. Deactivation of PF5 by water scavenging leads to the long‐term stability of the interfacial structures of electrodes. Moreover, an MA‐C60‐added electrolyte deactivates the reactive oxygen species and constructs an electrochemically robust cathode‐electrolyte interface for Li‐rich cathodes. This work paves the way for new possibilities in the design of electrolyte additives by eliminating undesirable reactive substances and tuning the interfacial structures of high‐capacity electrodes in LIBs.  相似文献   
146.

Background

Polo-like kinase-1 (Plk1) plays a crucial role in cell proliferation and the inhibition of Plk1 has been considered as a potential target for specific inhibitory drugs in anti-cancer therapy. Several research groups have identified peptide-based inhibitors that target the polo-box domain (PBD) of Plk1 and bind to the protein with high affinity in in vitro assays. However, inadequate proteolytic resistance and cell permeability of the peptides hinder the development of these peptide-based inhibitors into novel therapeutic compounds.

Methodology/Principal Findings

In order to overcome the shortcomings of peptide-based inhibitors, we designed and synthesized small molecule inhibitors. Among these molecules, bg-34 exhibited a high binding affinity for Plk1-PBD and it could cross the cell membrane in its unmodified form. Furthermore, bg-34-dependent inhibition of Plk1-PBD was sufficient for inducing apoptosis in HeLa cells. Moreover, modeling studies performed on Plk1-PBD in complex with bg-34 revealed that bg-34 can interact effectively with Plk1-PBD.

Conclusion/Significance

We demonstrated that the molecule bg-34 is a potential drug candidate that exhibits anti-Plk1-PBD activity and possesses the favorable characteristics of high cell permeability and stability. We also determined that bg-34 induced apoptotic cell death by inhibiting Plk1-PBD in HeLa cells at the same concentration as PEGylated 4j peptide, which can inhibit Plk1-PBD activity 1000 times more effectively than bg-34 can in in vitro assays. This study may help to design and develop drug-like small molecule as Plk1-PBD inhibitor for better therapeutic activity.  相似文献   
147.
The DJ-1 gene is highly conserved in diverse species and DJ-1 is known as an anti-oxidative stress factor. In this study, we investigated the neuroprotective effects of DJ-1 against ischemic damage in the rabbit spinal cord. Tat-DJ-1 fusion proteins were constructed to facilitate the penetration of DJ-1 protein into the neurons. Tat-1-DJ-1 fusion protein was administered to the rabbit 30 min after ischemia/reperfusion, and transient spinal cord ischemia was induced by occlusion of the aorta at the subrenal region for 15 min. The administration of Tat-DJ-1 significantly improved the Tarlov score compared to that in the Tat (vehicle)-treated group at 24, 48 and 72 h after ischemia/reperfusion. At 72 h after ischemia/reperfusion, the number of cresyl violet-positive neurons was significantly increased in the Tat-DJ-1-treated group compared to that in the vehicle-treated group. Lipid peroxidation as judged from the malondialdehyde levels was significantly decreased in the Tat-DJ-1-treated group compared to that in the vehicle-treated group. In contrast, superoxide dismutase and catalase levels were significantly increased in the Tat-DJ-1-treated group compared to that in the vehicle-treated group. This result suggests that DJ-1 protects neurons from ischemic damage in the ventral horn of the spinal cord via its antioxidant effects.  相似文献   
148.
Summary The progeny of Dichomitus squalens CBS-432-34 is heterogeneous with respect to specific growth rate on glucose, cellulolytic ([U14C]cellulose 14CO2) and ligninolytic ([14C]synthetic lignin 14CO2) activities with little correlation between these metric characters. Variations do not show clear-cut phenotypes but rather a continuous range between extreme values pointing to multigenic control of these characters. Most homocaryons showed decreased cellulolytic or ligninolytic activity compared to the parent dicaryon. However a few homocaryons were comparable or even superior to the parent dicaryon for ligninolytic or cellulolytic activity with no correlation between each factor. Strains with reduced cellulolytic activity and altered isozyme patterns of endoglucanases were isolated in the progeny of D. squalens CBS-432-34. While the parent strain produced three main endoglucanase multiple enzymes designated EnI, EnII and EnIII, several strains in the progeny produced a different multiple enzyme pattern. In contrast to the quantitative ability to degrade cellulose, multiple enzyme pattern variation in the progeny did not show continuous variations. characterization of heterocaryon phenotypes derived from Ien+ and Ien 1 homocaryons and first filial generation (f1) analysis showed that genetic control of the multiple enzyme pattern (Ien 1 phenotype) in D. squalens is complex. Offprint requests to: E. Odier  相似文献   
149.
Neurochemical Research - Neurodegenerative disorders are distinguished by the gradual deterioration of the nervous system’s structure and function due to oxidative stress, mitochondrial...  相似文献   
150.
The current report describes the chemical investigation and biological activity of extracts produced by three fungal strains Fusarium oxysporum, Penicillium simplicissimum, and Fusarium proliferatum isolated from the roots of Piper nigrum L. growing in Vietnam. These fungi were namely determined by morphological and DNA analyses. GC/MS identification revealed that the EtOAc extracts of these fungi were associated with the presence of saturated and unsaturated fatty acids. These EtOAc extracts showed cytotoxicity towards cancer cell lines HepG2, inhibited various microbacterial organisms, especially fungus Aspergillus niger and yeast Candida albicans (the MIC values of 50–100 μg/mL). In α-glucosidase inhibitory assay, they induced the IC50 values of 1.00-2.53 μg/mL were better than positive control acarbose (169.80 μg/mL). The EtOAc extract of F. oxysporum also showed strong anti-inflammatory activity against NO production and PGE-2 level. Four major compounds linoleic acid (37.346 %), oleic acid (27.520 %), palmitic acid (25.547 %), and stearic acid (7.030 %) from the EtOAc extract of F. oxysporum were selective in molecular docking study, by which linoleic and oleic acids showed higher binding affinity towards α-glucosidase than palmitic and stearic acids. In subsequent docking assay with inducible nitric oxide synthase (iNOS), palmitic acid, oleic acid and linoleic acid could be moderate inhibitors.  相似文献   
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