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211.
BACKGROUND AND AIMS. Molecular authentication of Korean ginseng cultivars was investigated using the mitochondrial nicotinamide adenine dinucleotide (NADH) dehydrogenase subunit 7 (nad7) intron 3 region. MATERIALS AND METHODS. A mutation site specific to Panax ginseng "Gumpoong" and "Chungsun" cultivars was detected within the sequence data. Based on this mutation site and the "Gumpoong"-specific single nucleotide polymorphism site reported in 26S rDNA, two modified allele-specific primer pairs were designed and a multiplex amplification refractory mutation system (MARMS) was applied to identify "Gumpoong" and "Chungsun." RESULTS. The results showed that "Gumpoong" and "Chungsun" can be clearly discriminated from the other Korean ginseng cultivars by simultaneously identifying the haplotype of "Gumpoong" and the specific allele of "Chungsun" by applying the MARMS. CONCLUSION. This study, therefore, provides a simple and reliable method for simultaneous authentication of "Gumpoong" and "Chungsun" cultivars. 相似文献
212.
Indomethacin is a nonsteroid anti-inflammatory agent that is known to induce severe gastric mucosal lesions. In this study, we investigated the effect of selenium on gastric mucosal lesions in rats. To confirm the curative effect of selenium against indomethacin-induced gastric ulcers, gastric ulcers were induced by oral administration of 25 mg/kg indomethacin, and then different doses (10, 50, and 100 microgram/kg of body weight) of selenium or vehicle were treated by oral gavage for 3 days. Oral administration of indomethacin clearly increased the gastric ulcer area in the stomach, whereas selenium applied for 3 days significantly decreased the gastric ulcer area in a dose-dependent manner. In addition, selenium markedly reduced the increase of lipid peroxidation induced by indomethacin in the gastric mucosa and increased activities of radical scavenging enzymes such as superoxide dismutase, catalase, and glutathione peroxidase in a dose-dependent manner. These results reveal that selenium can heal indomethacininduced gastric ulcers through elimination of the lipid peroxides and activation of radical scavenging enzymes. 相似文献
213.
Berberine exerts an anti-adipogenic activity that is associated with the down-regulation of C/EBPα and PPARγ. Stimulation of AMP-activated kinase (AMPK) caused by inhibition of mitochondrial respiration has been suggested to underlie such molecular regulation. In the present study, we show that berberine up-regulated the expression of two different sets of C/EBP inhibitors, CHOP and DEC2, while down-modulating C/EBPα, PPARγ and other adipogenic markers and effectors in differentiating 3T3-L1 preadipocytes and mature adipocytes. Data also suggested that the berberine-induced up-regulation of CHOP and DEC2 was attributable to selective activation of an unfolded protein response (UPR) and modified extracellular environment, respectively. As a result, the anti-adipogenic activity of berberine was diminished remarkably by adjusting the differentiation culture media and limitedly but consistently by knockdown of CHOP expression. Together, up-regulation of C/EBP inhibitors appears to underlie the berberine-induced repression of C/EBPα and PPARγ and, so, the inhibition of adipogenesis. 相似文献
214.
215.
Jung SH Ha YJ Shim EK Choi SY Jin JL Yun-Choi HS Lee JR 《The Biochemical journal》2007,403(2):243-250
Five pentacyclic triterpenoids isolated from Campsis grandiflora were tested for insulin-mimetic and insulin-sensitizing activity. The compounds enhanced the activity of insulin on tyrosine phosphorylation of the IR (insulin receptor) beta-subunit in CHO/IR (Chinese-hamster ovary cells expressing human IR). Among the compounds tested, CG7 (ursolic acid) showed the greatest enhancement and CG11 (myrianthic acid) the least. We characterized the effect of CG7 further, and showed that it acted as an effective insulin-mimetic agent at doses above 50 mug/ml and as an insulin-sensitizer at doses as low as 1 mug/ml. Additional experiments showed that CG7 increased the number of IRs that were activated by insulin. This indicates that a major mechanism by which CG7 enhances total IR auto-phosphorylation is by promoting the tyrosine phosphorylation of additional IRs. CG7 not only potentiated insulin-mediated signalling (tyrosine phosphorylation of the IR beta-subunit, phosphorylation of Akt and glycogen synthase kinase-3beta), but also enhanced the effect of insulin on translocation of glucose transporter 4 in a classical insulin-sensitive cell line, 3T3-L1 adipocytes. The results of the present study demonstrate that a specific pentacyclic triterpenoid, CG7, exerts an insulin-sensitizing effect as an IR activator in CHO/IR cells and adipocytes. The enhancement of insulin activity by CG7 may be useful for developing a new class of specific IR activators for treatment of Type 1 and Type 2 diabetes. 相似文献
216.
NSAID activated gene (NAG-1), a modulator of tumorigenesis 总被引:2,自引:0,他引:2
The NSAID activated gene (NAG-1), a member of the TGF-beta superfamily, is involved in tumor progression and development. The over-expression of NAG-1 in cancer cells results in growth arrest and increase in apoptosis, suggesting that NAG-1 has anti-tumorigenic activity. This conclusion is further supported by results of experiments with transgenic mice that ubiquitously express human NAG-1. These transgenic mice are resistant to the development of intestinal tumors following treatment with azoxymethane or by introduction of a mutant APC gene. In contrast, other data suggest a pro-tumorigenic role for NAG-1, for example, high expression of NAG-1 is frequently observed in tumors. NAG-1 may be like other members of the TGF-beta superfamily, acting as a tumor suppressor in the early stages, but acting pro-tumorigenic at the later stages of tumor progression. The expression of NAG-1 can be increased by treatment with drugs and chemicals documented to prevent tumor formation and development. Most notable is the increase in NAG-1 expression by the inhibitors of cyclooxygenases that prevent human colorectal cancer development. The regulation of NAG-1 is complex, but these agents act through either p53 or EGR-1 related pathways. In addition, an increase in NAG-1 is observed in inhibition of the AKT/GSK-3beta pathway, suggesting NAG-1 alters cell survival. Thus, NAG-1 expression is regulated by tumor suppressor pathways and appears to modulate tumor progression. 相似文献
217.
Han Gil Seo Nam-Jong Paik Shi-Uk Lee Byung-Mo Oh Min Ho Chun Bum Sun Kwon Moon Suk Bang 《PloS one》2015,10(6)
Background
Botulinum toxin type A is widely used for treating spasticity. Neuronox (Neu-BoNT/A), a newly manufactured botulinum toxin a, has not yet been investigated for its efficacy and safety in the treatment of post-stroke upper limb spasticity.Objective
We evaluated the efficacy and safety of Neuronox (Neu-BoNT/A) compared with BOTOX (onabotulinum toxin A) for treating post-stroke upper limb spasticity.Methods
In total, 196 stroke patients with moderate to severe upper limb spasticity were randomly assigned to either Neuronox or BOTOX intervention. The wrist flexors were mandatory and elbow, finger, and thumb flexors were optional muscles to be injected. Assessments were performed at baseline and 4, 8, and 12 weeks after the intervention. The primary outcome measure was the change from baseline of the Modified Ashworth Scale (MAS) at the wrist flexors at week 4. Secondary outcome measures included the change of MAS at each visit, response rate, Disability Assessment Scale (DAS), Carer Burden Scale, and Global Assessment of treatment benefit.Results
Primary outcome measures were -1.39±0.79 and -1.56±0.81 in the Neuronox and BOTOX groups, respectively. The difference was within the noninferiority margin of 0.45 (95% upper limit=0.40). There were no significant differences between the groups in the secondary outcome and safety measures, except the change of the MAS at the elbow flexors at week 12 (-0.88±0.75 in the Neuronox group, -0.65±0.74 in the BOTOX group; P=0.0429). Both groups showed significant improvements in the MAS, DAS, and Carer Burden Scale at weeks 4, 8, and 12.Conclusion
Neuronox showed equivalent efficacy and safety compared with BOTOX for treating post-stroke upper limb spasticity.Trial Registration
ClinicalTrials.gov NCT01313767 相似文献218.
Moon Hee Jeong Shang-Jin Kim Hara Kang Kye Won Park Woo Jin Park Seung Yul Yang Dong Kwon Yang 《PloS one》2015,10(8)
Cucurbitacin I is a naturally occurring triterpenoid derived from Cucurbitaceae family plants that exhibits a number of potentially useful pharmacological and biological activities. However, the therapeutic impact of cucurbitacin I on the heart has not heretofore been reported. To evaluate the functional role of cucurbitacin I in an in vitro model of cardiac hypertrophy, phenylephrine (PE)-stimulated cardiomyocytes were treated with a sub-cytotoxic concentration of the compound, and the effects on cell size and mRNA expression levels of ANF and β-MHC were investigated. Consequently, PE-induced cell enlargement and upregulation of ANF and β-MHC were significantly suppressed by pretreatment of the cardiomyocytes with cucurbitacin I. Notably, cucurbitacin I also impaired connective tissue growth factor (CTGF) and MAPK signaling, pro-hypertrophic factors, as well as TGF-β/Smad signaling, the important contributing factors to fibrosis. The protective impact of cucurbitacin I was significantly blunted in CTGF-silenced or TGF-β1-silenced hypertrophic cardiomyocytes, indicating that the compound exerts its beneficial actions through CTGF. Taken together, these findings signify that cucurbitacin I protects the heart against cardiac hypertrophy via inhibition of CTGF/MAPK, and TGF- β/Smad-facilitated events. Accordingly, the present study provides new insights into the defensive capacity of cucurbitacin I against cardiac hypertrophy, and further suggesting cucurbitacin I’s utility as a novel therapeutic agent for the management of heart diseases. 相似文献
219.
So-Jung Kwon Kyuyong Han Suhyun Jung Jong-Eun Lee Seongsoon Park Yong-Pil Cheon Jade Hyunjung Lim 《BMC biotechnology》2009,9(1):73
Background
MPG is a cell-permeable peptide with proven efficiency to deliver macromolecular cargoes into cells. In this work, we examined the efficacy of MPG as an N-terminal tag in a fusion protein to deliver a protein cargo and its mechanism of transduction. 相似文献220.
Yoo KY Yoo DY Hwang IK Park JH Lee CH Choi JH Kwon SH Her S Lee YL Won MH 《Neurochemical research》2011,36(12):2417-2426
Innate immune system is very important to modulate the host defense against a large variety of pathogens. Toll-like receptors
(TLRs) play a key role in controlling innate immune response. Among TLRs, TLR4 is a specific receptor for lipopolysaccharide
and associated with the release of pro-inflammatory cytokines. In the present study, we investigated ischemia-related changes
of TLR4 immunoreactivity and its protein level, and nuclear factor κB (NF-κB) p65 immunoreactivity regarding inflammatory
responses in the hippocampal CA1 region after 5 min of transient cerebral ischemia to identify the correlation between transient
ischemia and inflammation. In the sham-operated group, TLR4 immunoreactivity was easily detected in pyramidal neurons of the
hippocampal CA1 region (CA1). TLR4 immunoreactivity in pyramidal neurons was distinctively decreased after ischemia/reperfusion
(I/R); instead, based on double immunofluorescence study, TLR4 immunoreactivity was expressed in non-pyramidal neurons and
astrocytes from 2 days postischemia. In addition, TLR4 protein level was lowest at 1 day postischemia and highest 4 days after
I/R. On the other hand, NF-κB p65 immunoreactivity was not detected in the CA1 of the sham-operated group, and NF-κB p65 immunoreactivity
was not observed until 1 day after I/R. However, NF-κB p65 immunoreactivity began to be expressed in astrocytes at 2 days
postischemia, and the immunoreactivity was strong 4 days postischemia. Our results indicate that TLR4 and NF-κB p65 immunoreactivity
are changed in CA1 pyramidal neurons and newly expressed in astrocytes, not in microglia, in the CA1 region after transient
cerebral ischemia. 相似文献