24 research outputs found
The Efficacy and Safety of the Combination of Total Glucosides of Peony and Leflunomide for the Treatment of Rheumatoid Arthritis: A Systemic Review and Meta-Analysis
Objective. To evaluate the efficacy and safety of the total glucosides of peony (TGP) and leflunomide (LEF) for the treatment of rheumatoid arthritis (RA). Methods. Randomized controlled trials (RCTs) on the efficacy and safety of the combination of TGP and LEF versus LEF alone for the treatment of RA were retrieved by searching PubMed, EMBASE, Cochrane Library, the China National Knowledge Infrastructure database, and Wanfang database. Results. Eight RCTs including 643 RA patients were included in the present meta-analysis. The quality of included studies was poor. The levels of ESR ( < 0.0001), CRP ( < 0.0001), and RF ( < 0.0001) in RA patients who received the combination of TGP and LEF were significantly lower than RA patients who received LEF therapy alone. The pooled results suggest that the combination of TGP and LEF caused less abnormal liver function than LEF alone ( = 0.02). No significant difference in the gastrointestinal discomfort was identified between the combination of TGP and LEF and LEF alone groups ( = 0.18). Conclusion. The combination of TGP and LEF in treatment of RA presented the characteristics of notably decreasing the levels of laboratory indexes and higher safety in terms of liver function. However, this conclusion should be further investigated based on a larger sample size
Aberrant allele frequencies of the SNPs located in microRNA target sites are potentially associated with human cancers
MicroRNAs (miRNAs) are a class of noncoding small RNAs that regulate gene expression by base pairing with target mRNAs at the 3′-terminal untranslated regions (3′-UTRs), leading to mRNA cleavage or translational repression. Single-nucleotide polymorphisms (SNPs) located at miRNA-binding sites (miRNA-binding SNPs) are likely to affect the expression of the miRNA target and may contribute to the susceptibility of humans to common diseases. We herein performed a genome-wide analysis of SNPs located in the miRNA-binding sites of the 3′-UTR of various human genes. We found that miRNA-binding SNPs are negatively selected in respect to SNP distribution between the miRNA-binding ‘seed’ sequence and the entire 3′-UTR sequence. Furthermore, we comprehensively defined the expression of each miRNA-binding SNP in cancers versus normal tissues through mining EST databases. Interestingly, we found that some miRNA-binding SNPs exhibit significant different allele frequencies between the human cancer EST libraries and the dbSNP database. More importantly, using human cancer specimens against the dbSNP database for case-control association studies, we found that twelve miRNA-binding SNPs indeed display an aberrant allele frequency in human cancers. Hence, SNPs located in miRNA-binding sites affect miRNA target expression and function, and are potentially associated with cancers
Identification of Pns6, a putative movement protein of RRSV, as a silencing suppressor
RNA silencing is a potent antiviral response in plants. As a counterdefense, most plant and some animal viruses encode RNA silencing suppressors. In this study, we showed that Pns6, a putative movement protein of Rice ragged stunt virus (RRSV), exhibited silencing suppressor activity in coinfiltration assays with the reporter green fluorescent protein (GFP) in transgenic Nicotiana benthamiana line 16c. Pns6 of RRSV suppressed local silencing induced by sense RNA but had no effect on that induced by dsRNA. Deletion of a region involved in RNA binding abolished the silencing suppressor activity of Pns6. Further, expression of Pns6 enhanced Potato virus × pathogenicity in N. benthamiana. Collectively, these results suggested that RRSV Pns6 functions as a virus suppressor of RNA silencing that targets an upstream step of the dsRNA formation in the RNA silencing pathway. This is the first silencing suppressor to be identified from the genus Oryzavirus
Functional Characterization of Human Calcium-Dependent Cysteine Protease, Calpain 1 ([mu]-Calpain), Using RNA Interference Technology
1 volumeCalpains are calcium-dependent cysteine proteases consisting of two major isoforms, m-calpain and f!-calpain, which have been implicated in aspects of carcinogenesis. However, the individual physiological function and biochemical mechanism for these two isoforms involved in cell motility are not clear. In the present study, in vitro synthesized human u-calpain specific siRNAs were able to significantly knockdown. u-calpain expression. Accordingly, stable MCF-7 cell lines expressing the functional u-calpain siRNAs were established. Casein zymography revealed that the enzymatic activity of u-calpain was reduced in comparison with that of the control cell line. The cells with an 80 % knockdown of u-calpain expression displayed reduced cell mobility and significant morphology changes. In addition, knockdown of u-calpain decreased the proteolytic products of filamin and talin, suggesting that their proteolysis could be one of the key mechanisms by which u-calpain regulates cell migration. Thus siRNAs can function as calpain isoform-specific inhibitors for the study of isoform functions and related intracellular signaling in carcinogenesis, and may have potential for therapeutic use.Les calpaines font partie de la famille des protéases à cystéine. Elles sont décrites comme des protéases neutres à activités calcium dépendantes. Au sein des calpaines, on distingue différents isoformes dont la u -calpaine et la m-calpaine. Ces dernières sont connus dans divers aspects de la cancérogenèse. Cependant, la fonction physiologique et le mécanisme biochimique de ces deux isoformes, aussi impliqués dans la motilité des cellules, demeurent ambiguës. Dans la présente étude, des siRNAs, synthétisés in vitro, spécifiques de u-Calpaine humaine ont supprimé de manière significative l'expression de u-Calpaine. Ensuite, une lignée stable de cellules MCF-7 exprimant des siRNAs fonctionnels de u-Calpaine a été établie. La zymographie de la caséine de cette lignée stable démontra que l'activité enzymatique de leur u-Calpaine a été réduite en comparaison de celle du témoin négatif. De plus, les cellules démontrant une suppression de 80% de !'expression de leur u-calpaine démontraient une mobilité cellulaire réduite et des changements morphologiques importants. Enfin, la suppression de l’expression de u-calpaine a diminué les produits protéolytiques de filamine et de taline, suggérant que leur protéolyse pourrait être l'un des principaux mécanismes par lesquels la u-Calpaine régulerait la migration de cellules. Ainsi, il a été démontré que les siRNAs exerce un rôle d'inhibiteurs spécifiques des isoformes de calpaine. Ils sont utiles pour étudier la physiologie cellulaire et certains processus de signalisation intracellulaire impliques dans la cancérogenèse. Leur potentiel dans le développement d'une thérapie est prometteur
New feruloyl esterases to access phenolic acids from grass biomass
In the Sorangium cellulosum strain So ce56 genome, two putative esterase-encoding genes (loci sce1896 and sce8927) were cloned, expressed in Escherichia coli, and the resulting enzymes (designated ScFAE1 and ScFAE2) were used to assess the possible release of ferulic acid (FA) from triticale and wheat brans, and an aqueous fraction of steam-exploded wheat straw. The two polypeptides, sharing only 30% sequence identity, exhibit a typical catalytic Ser-Asp-His triad, a characteristic of \u3b1/\u3b2-hydrolase fold proteins. Both ScFAE1 (35 kDa) and ScFAE2 (34 kDa) were purified to apparent homogeneity and comparison of their kinetic parameters indicated an apparent higher affinity of ScFAE2 than ScFAE1 towards the various feruloyl substrates. This property was reflected by the observation that ScFAE2 was capable of yielding up to 85% of FA from destarched triticale bran. In the steam-exploded wheat sample, more than 85% yield of FA or p-coumaric acid was also effected by ScFAE2 without the decomposition of valuable chemical such as furfural. The two cloned FAEs represent the first of myxobacterial origin to be characterized and they are classified as new members of the type D family of FAEs.Peer reviewed: YesNRC publication: Ye
Thermostable feruloyl esterase for the bioproduction of ferulic acid from triticale bran
A putative \u3b1/\u3b2 hydrolase fold-encoding gene (locus tag TTE1809) from the genome of Thermoanaerobacter tengcongensis was cloned and expressed in Escherichia coli as a possible source of thermostable feruloyl esterase (FAE) for the production of antioxidant phenolic acids from biomass. Designated as TtFAE, the 33-kDa protein was purified to apparent homogeneity. The lipase-like sequence characteristics of TtFAE and its substrate specificity towards methyl ferulate, methyl sinapate, and methyl p-coumarate classify it as a new member of the type A FAEs. At 75\ub0C, the enzyme retained at least 95% of its original activity for over 80 min; at 80\ub0C, its half-life was found to be 50 min, rendering TtFAE a highly thermostable protein. Under different hydrolytic conditions, ferulic acid (FA) was shown to be released from feruloylated oligosaccharides prepared from triticale bran. An estimated recovery of 68 mg FA/100 g triticale bran was demonstrated by a 30% release of the total FA from triticale bran within a 5-h incubation period. Both the oxygen radical absorbing capacity values of the feruloylated oligosaccharides and free FA were also determined. Overall, this work introduces a new bacterial member to the growing family of plant cell wall degrading FAEs that at present is largely of fungal origin, and it benchmarks the bioproduction of FA from triticale bran.Peer reviewed: YesNRC publication: Ye
Direct fermentation of triticale starch to lactic acid by Rhizopus oryzae
The production of lactic acid from triticale starch was demonstratedfor the first time. Direct fermentation by Rhizopus oryzae in batch modeled to a conversion yield of 0.74 g lactic acid/g starch. Kinetics analysisof the fermentation suggested a multiphase process which consistedof quick hydrolysis of starch, rapid glucose accumulation followedby fast production of lactic acid. In batch fermentation mode, correcttiming and proper dosage of a neutralizing agent (calcium carbonate)were found to be critical factors that affect the organic acid yield.Addition of CaCO3 at the time point when glucose accumulationhad reached its peak (24 h) resulted in the highest lactic acid yield.The best ratio (by weight) of triticale starch to CaCO3 for lactic acidproduction was 1:1. It was important to maintain a pH of about 5during the whole fermentation process. Fermentation carried out inan optimized, commercially available small-scale parallel bioreactor(DASGIP) yielded up to 0.87 g lactic acid/g triticale starch whenR. oryzae spores were directly added to the fermentation medium. Ourfermentation results indicated that triticale starch from this nonfoodcrop is a promising renewable feedstock for production of lactic acidPeer reviewed: YesNRC publication: Ye
Functional dissection of human protease \u3bc-calpain in cell migration using RNAi
Calpains are a family of calcium-dependent cysteine proteases involved in a variety of cellular functions. Two isoforms, m-calpain and \u3bc-calpain, have been implicated in cell migration. However, since conventional inhibitors used for the studies of the functions of these enzymes lack specificity, the individual physiological function and biochemical mechanism of these two isoforms, especially \u3bc-calpain, are not clear. In contrast, RNA interference has the potential to allow a sequence-specific destruction of target RNA for functional assay of gene of interest. In the present study, we found that small interfering RNAs-mediated knockdown of \u3bc-calpain expression in MCF-7 cells that do not express m-Calpain led to a reduction of cell migration. This isoform-specific function of \u3bc-calpain was further confirmed by the rescue experiment as overexpression of \u3bc-calpain but not m-calpain could restore the cell migration rate. Knockdown of \u3bc-calpain also altered cell morphology with increased filopodial projections and a highly elongated tail that seemed to prevent cell spreading and migration with reduced rear detachment ability. Furthermore, knockdown of \u3bc-calpain decreased the proteolytic products of filamin and talin, which were specifically rescued by overexpression of \u3bc-calpain but not m-calpain, suggesting that their proteolysis could be one of the key mechanisms by which \u3bc-calpain regulates cell migration.NRC publication: Ye