原田病药物治疗后吲哚青绿眼底血管造影观察

目的 探讨利用吲哚青绿血管造影检查作为原田(Harada)病临床观察指标的意义.方法 对经药物治疗后19例(38只眼)原田病患者同时行荧光素眼底血管造影(fundus fluorescein angiography,FFA)及吲哚青绿血管造影(indocyanine green angiography,ICGA)检查资料进行分析.结果 FFA检查发现有4例(8只眼)视盘轻度染色,视网膜未发现异常改变;ICGA早期及中期无异常表现,但后期8只眼(包括FFA中视盘染色的4只眼)在中周及后极部出现了点状或斑片状弱荧光;3例6只眼FFA及眼底正常,在ICGA后期后极部出现了斑点状弱荧光;24只眼脉络膜大、中血管影像减少,其中12只眼dalen-fuchs结节着色.结论 ICGA可较好提供原田病的脉络膜循环损害的信息,并在评价疗效上有意义.

Abstract：

Objective To investigate the clinical value of indocyanine green angiography(ICGA)in patients with Harada disease.Methods Fundus fluorescein angiography(FFA)and indocyanine green angiography(ICGA)were used for comparative analyses in 26 cases(52 eyes)of Harada disease after treatment.Results Mild dyeing in disk was found only in 4 cases(8 eyes),and the others were not found any abnormal in FFA.There were no any abnormal found in early period and middle period of ICGA,but of 8 eyes(include 4 eyes of dyeing in disk in FFA)multifocal lower fluorescence were found in the mid-periphery and posterior pole of the fundus in the late phase.Of 3 cases(6 eyes)were normal in FFA,however multifocal lower fluorescence were found in the posterior pole of the fundus in the late phase of ICGA.Of 24 eyes were found decreased fluorescence in large and middle choroidal vessel,and 12 eyes of Dalen-Fuchs were colored.Conclusions ICGA may assist in providing valuable information on choroidal circulation of Harada disease and be useful in evaluating the curative effects.     

Cancer chemoprevention by tea polyphenols through modulating signal transduction pathways

The action mechanisms of several chemopreventive agents derived from herbal medicine and edible plants have become attractive issues in cancer research. Tea is the most widely consumed beverage worldwide. Recently, the cancer chemopreventive actions of tea have been intensively investigated. It have been demonstrated that the active principles of tea were attributed to their tea polyphenols. Recently, tremendous progress has been made in elucidating the molecular mechanisms of cancer chemoprevention by tea and tea polyphenols. The suppression of various tumor biomarkers including growth factor receptor tyrosine kinases, cytokine receptor kinases, PI3K, phosphatases, ras, raf, MAPK cascades, N x FB, I x B kinase, PKA, PKB, PKC, c-jun, c-fos, c-myc, cdks, cyclins, and related transducing proteins by tea polyphenols has been studied in our laboratory and others. The I x B kinase (IKK) activity in LPS-activated murine macrophages (RAW 264.7 cells) was found to be inhibited by various tea polyphenols including (-) epigallocatechin-3-gallate (EGCG), theaflavin (TF-1), theaflavin-3-gallate (TF-2) and theaflavin-3,3'-digallate (TF-3). TF-3 inhibited IKK activity in activated macrophages more strongly than did the other tea polyphenols. TF-3 inhibited both IKK1 and IKK2 activity and prevented the degradation of I x B x and I x B x in activated macrophage cells. The results suggested that the inhibition of IKK activity by TF-3 and other tea polyphenols could occur by a direct effect on IKKs or on upstream events in the signal transduction pathway. TF-3 and other tea polyphenols blocked phosphorylation of IB from the cytosolic fraction, inhibited NFB activity and inhibited increases in inducible nitric oxide synthase levels in activated macrophage. TF-3 and other tea polyphenols also inhibited strongly the activities of xanthine oxidase, cyclooxygenase, EGF-receptor tyrosine kinase and protein kinase C. These results suggest that TF-3 and other tea polyphenols may exert their cancer chemoprevention through suppressing tumor promotion and inflammation by blocking signal transduction. The mechanisms of this inhibition may be due to the blockade of the mitogenic and differentiating signals through modulating EGFR function, MAPK cascades, NFkappaB activation as well as c-myc, c-jun and c-fos expression.     

Inhibition of homodimerization of Toll-like receptor 4 by curcumin

Toll-like receptors play a key role in sensing microbial components and inducing innate immune responses. Ligand-induced dimerization of TLR4 is required for the activation of downstream signaling pathways. Thus, the receptor dimerization may be one of the first lines of regulation in activating TLR-mediated signaling pathways and induction of subsequent immune responses. LPS induces the activation of NF-kappaB and IRF3 through MyD88- or TRIF-dependent pathways. Curcumin, a polyphenol found in the plant Curcuma longa, has been shown to suppress the activation of NF-kappaB induced by various pro-inflammatory stimuli by inhibiting IKKbeta kinase activity in MyD88-dependent pathway. Curcumin also inhibited LPS-induced IRF3 activation. These results imply that curcumin inhibits both MyD88- and TRIF-dependent pathways in LPS-induced TLR4 signaling. However, in TRIF-dependent pathway, curcumin did not inhibit IRF3 activation induced by overexpression of TRIF in 293T cells. These results suggest that TLR4 receptor complex is the molecular target of curcumin in addition to IKKbeta. Here, we report biochemical evidence that phytochemicals (curcumin and sesquiterpene lactone) inhibit both ligand-induced and ligand-independent dimerization of TLR4. Furthermore, these results demonstrate that small molecules with non-microbial origin can directly inhibit TLRs-mediated signaling pathways at the receptor level. These results imply that the activation of TLRs and subsequent immune/inflammatory responses induced by endogenous molecules or chronic infection can be modulated by certain dietary phytochemicals we consume daily.     

Pharmacological effects of green tea on the gastrointestinal system

Green tea is rich in polyphenolic compounds, with catechins as its major component. Studies have shown that catechins possess diverse pharmacological properties that include anti-oxidative, anti-inflammatory, anti-carcinogenic, anti-arteriosclerotic and anti-bacterial effects. In the gastrointestinal tract, green tea was found to activate intracellular antioxidants, inhibit procarcinogen formation, suppress angiogenesis and cancer cell proliferation. Studies on the preventive effect of green tea in esophageal cancer have produced inconsistent results; however, inverse relationships of tea consumption with cancers of the stomach and colon have been widely reported. Green tea is effective to prevent dental caries and reduce cholesterols and lipids absorption in the gastrointestinal tract, thus benefits subjects with cardiovascular disorders. As tea catechins are well absorbed in the gastrointestinal tract and they interact synergistically in their disease-modifying actions, thus drinking unfractionated green tea is the most simple and beneficial way to prevent gastrointestinal disorders.     

Effect of gamma irradiation on phenol content,antioxidant activity and biological activity of black maca and red maca extracts (Lepidium meyenii walp)

This study was performed to determine the effects of gamma irradiation on UV spectrum on maca, total content of polyphenols, 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activities and in vivo biological activities of red and black maca extracts (Lepidium meyenii).

Adult mice of the strain Swiss aged 3 months and weighing 30–35?g in average were used to determine biological activities. Daily sperm production, effect on testosterone-induced prostate hyperplasia and forced swimming test were used to determine the effect of irradiation on biological activities of maca extracts.

Irradiation did not show differences in UV spectrum but improves the amount of total polyphenols in red maca as well as in black maca extracts. In both cases, black maca extract has more content of polyphenols than red maca extract (p?<?0.01). Gamma irradiation significantly increased the antioxidant capacity (p?<?0.05).

No difference was observed in daily sperm production when irradiated and nonirradiated maca extract were administered to mice (p?>?0.05). Black maca extract but not red maca extract has more swimming endurance capacity in the forced swimming test. Irradiation of black maca extract increased the swimming time to exhaustion (p?<?0.05). This is not observed with red maca extract (p?>?0.05). Testosterone enanthate (TE) increased significantly the ventral prostate weight. Administration of red maca extract in animals treated with TE prevented the increase in prostate weight. Irradiation did not modify effect of red maca extract on prostate weight (p?>?0.05).

In conclusion, irradiation does not alter the biological activities of both black maca and red maca extracts. It prevents the presence of microorganisms in the extracts of black or red maca, but the biological activities were maintained.     

Establishment of an Evaluation Method for Gene Silencing by Serial Pulmonary Administration of siRNA and pDNA Powders: Naked siRNA Inhalation Powder Suppresses Luciferase Gene Expression in the Lung

In order to evaluate the in vivo effect of inhaled formulations, it is a gold standard to create a lung metastasis model by intravenously injecting cancer cells into an animal. Because the cancer grows from the blood vessel side, there is a possibility of underestimating the effect of an inhaled formulation administered to the lung epithelium side. In addition, the metastasis model has disadvantages in terms of preparation time and expense. The present study aimed to establish a new method to evaluate the effect of an inhaled small interfering RNA (siRNA) formulation that is more correct, more rapid, and less expensive. We investigated whether siRNA can suppress gene expression of plasmid DNA (pDNA) by serial pulmonary administration of siRNA and pDNA powders prepared by spray-freeze-drying. We revealed that formulations of dry siRNA powder significantly suppressed gene expression of pDNA powder compared with a control group with no siRNA. Naked siRNA inhalation powder with no vector showed the suppression of gene expression equivalent to that of an siRNA-polyethyleneimine complex without damaging tissues. These results show that the present method is suitable for evaluating the gene-silencing effect of inhaled siRNA powders.     

siRNA沉默肝癌细胞报告基因瞬时表达效应的定量分析

目的研究小分子干扰RNA(siRNA)特异性抑制肝癌细胞基因瞬时表达的可行性和基因沉默效率。方法凝胶电泳成像观察siRNA体外孵育后的降解性,利用Cy3示踪观察其转染HepG2细胞后动力学变化。将报告基因(GFP)和siRNA共同瞬时转染至HepG2细胞,流式细胞仪、Western blot RT-PCR等分析特异性siRNA抑制报告基因瞬时表达的效应。结果siRNA在空白培养液中和转染细胞内可较长时间保持相对稳定。与空白和非特异siRNA相比,GFPsiR-NA明显抑制GFP蛋白产物和mRNA的表达(P<0·05)。结论特异性siRNA能高效沉默人肝癌细胞转染基因的瞬时表达,为基因治疗提供了一种新的治疗策略。     

吲哚菁绿光热治疗耐甲氧西林葡萄球菌感染的研究

目的　探讨吲哚菁绿（ICG）的光热治疗（PTT）性能及对耐甲氧西林葡萄球菌的杀灭效果。方法　利用紫外和荧光光谱对ICG的光物理性质进行表征;测定不同质量浓度ICG（0、12.5、25、50、100和200 mg/L）的光热升温曲线,评估ICG的光热转化性能;取小鼠乳腺癌4T1细胞与不同质量浓度的ICG溶液（0、50、100、200和500 mg/L）混合,通过MTT实验检测ICG的细胞毒性;取1×1010 CFU/mL的耐甲氧西林的金黄色葡萄球菌加入到96孔板中,将实验分为7组：PBS组、ICG组（500 mg/L）、激光照射组（1.5 W/cm2的808 nm激光照射10 min）、ICG+0.33 W/cm2激光照射组、ICG+0.66 W/cm2激光照射组、ICG+1 W/cm2激光照射组、ICG+1.5 W/cm2激光照射组,观察并记录存活的菌落数,分析基于ICG的PTT杀菌效果。结果　紫外吸收光谱证实ICG在808 nm处具有较强的光吸收能力;ICG溶液（质量浓度为200 mg/L）经功率密度为1.5 W/cm2的808 nm近红外激光照射10 min后,温度可升高23.3 ℃,而纯水的温度仅升高了4.8 ℃。ICG不同质量浓度组即50、100、200、500 mg/L组的细胞生存率分别为81.87%±2.69%、81.47%±2.94%、82.92%±2.61%、80.44%±2.98%,组间差异无统计学意义（F=0.402,P＞0.05）。不同功率密度激光照射组即0.33、0.66、1、1.5 W/cm2组的细胞生存率分别为97.21%±1.59%、94.92%±1.98%、93.89%±1.38%、93.03%±2.31%,组间差异无统计学意义（F=2.864,P＞0.05）。杀菌实验中,与PBS组比较,ICG+激光照射组随着激光功率密度的升高,细菌存活数量逐渐下降,差异有统计学意义（F=133.800,P＜0.01）。结论　ICG具有良好的生物相容性和光热治疗性能,在近红外激光照射下对耐甲氧西林葡萄球菌具有较强的杀灭效果,具有较好的临床转化应用价值。     

茶多酚抑制MDA生成及对阿霉素在小鼠肝细胞内蓄积的影响

荧光光度法测定 MDA及阿霉素在小鼠肝细胞内的含量 ;研究茶多酚抑制 MDA的生成与阿霉素胞内蓄积的关系。结果表明 ,茶多酚浓度为 1 0 ,2 0 ,40 ,80 ,1 60 mg/L时对 MDA生成的抑制率分别为 44.87% ,1 1 5.1 7% ,1 77.2 5% ,1 81 .98% ,1 82 .37% ,且与剂量成正相关。在·OH诱导下 ,茶多酚浓度为 40 mg/L时 ,可明显增加阿霉素在小鼠肝组织细胞内的蓄积     

植物多酚类成分提取分离研究进展

植物多酚是一种广泛存在于植物体内的多元酚类次生代谢产物,随着多酚类成分在抗氧化、抗菌、抗病毒、抗微生物、调血脂和血糖等多方面活性的发现和阐明,植物多酚成为当前研究的热点之一.多酚类成分由于其结构上的复杂性和不稳定性,目前在提取分离上还存在一定的困难.对中药中多酚类成分的提取分离方法进行总结,旨在为下一步分离纯化多酚类成分提供比较系统的信息依据.