Addition of a propyl gallate-based procoagulant to a fibrin bandage improves hemostatic performance in a swine arterial bleeding model

Fibrin bandages manufactured by Nycomed Austria (TC-S) were modified by the addition of Hemostyptin (HS), a proprietary platelet-activating reagent containing propyl gallate. HS was added as an additional layer to TC-S fibrin bandages and the bandages were tested for hemostatic efficacy in a swine femoral artery bleeding model. Injuries were treated with a TC-S+HS bandage preparation using HS lyophilized onto a bandage surface that was then attached to the fibrin dressing. This preparation qualitatively and quantitatively exhibited more robust blood clotting at the surgical site than the control bandages. TC-S+HS bandages were more effective than control bandages with a difference in blood loss of 251.8±66.5 g for TC-S bandage alone, n=12 vs. 121±40.7 g, n=13 for the TC-S+HS bandage, P=0.05. Bleeding times were shortened for animals treated with the HS fortified bandages and residual platelets counts in these animals were higher.     

Epigallocatechin gallate prevents autoimmune diabetes induced by multiple low doses of streptozotocin in mice

Cytokines produced by immune cells infiltrating pancreatic islets have been incriminated as important mediators of beta-cell destruction in insulin-dependent diabetes mellitus. In non insulin-dependent diabetes, cytokines are also associated with impaired beta-cell function in high glucose condition. By the screening of various natural products blocking beta-cell destruction, we have recently found that epigallocatechin gallate (EGCG) can prevent the in vitro destruction of RINm5F cell, an insulinoma cell line, that is induced by cytokines. In that study we suggested that EGCG could prevent cytokine-induced beta-cell destruction by down-regulation of nitric oxide synthase (NOS) through inhibition of NF-kappaB activation. Here, to verify the in vivo antidiabetogenic effect of EGCG, we examined the possibility that EGCG could also prevent the experimental autoimmune diabetes induced by the treatment of multiple low doses of streptozotocin (MLD-STZ), which is recognized as an inducer of type I autoimmune diabetes. Administration of EGCG (100 mg/day/kg for 10 days) during the MLD-STZ induction of diabetes reduced the increase of blood glucose levels caused by MLD-STZ. Ex vivo analysis of beta-islets showed that EGCG downregulates the MLD-STZ-induced expression of inducible NOS (iNOS). In addition, morphological examination showed that EGCG treatment ameliorated the decrease of islet mass induced by MLD-STZ. In combination these results suggest that EGCG could prevent the onset of MLD-STZ-induced diabetes by protecting pancreatic islets. Our results therefore revealed the possible therapeutic value of EGCG for the prevention of diabetes mellitus progression.     

高效液相色谱法测定家兔血浆中赤芍_(801)的浓度

用反相高效液相色谱法测定家兔血浆中赤芍８０１ＰＧ浓度。采用ＮｕｃｉｅｏｓｅｌＣ１８色谱柱，甲醇∶水∶冰乙酸（４８∶５０∶２）为流动相，４羟基苯甲酸乙酯为内标物，紫外检测波长２７５ｎｍ，对ｉｖＰＧ后不同时间家兔血浆中药物含量进行测定。结果表明：ＰＧ浓度为２．５μｇ／ｍｌ的平均回收率为９６．７０％，其ＲＳＤ＝１．８３％。浓度５μｇ／ｍｌ的样品平均回收率为９８．８６％，ＲＳＤ＝１．０５％。其最低检测限为０．１μｇ／ｍｌ。     

大黄及其有效成分抗炎作用的研究进展

大黄为廖科植物药用大黄Rheum officinale、掌叶大黄R. palmatu或唐古特大黄R. tanguticum的干燥根和根茎,具有泻下攻积、清热泻火、凉血解毒、逐瘀通经、利湿退黄等功效,是我国用药历史悠久的大宗中药材。现代药理学研究表明大黄药材、提取物和单体化合物具有优良的抗炎活性,可调节炎症小体的激活,其主要通过调控氧化应激、细胞凋亡、免疫应答等细胞过程,以及调控炎症相关蛋白和相关炎症通路等多种途径对心血管、胃肠道和中枢神经系统相关疾病表现出显著的药理活性,特别是具有较好的抗神经炎症效果。总结了大黄提取物和蒽醌类、鞣质类、二苯乙烯类成分在炎症相关疾病中的药理活性及作用机制的研究进展,并对其发展趋势进行了展望,为大黄的临床应用、进一步开发利用和新药研发提供理论支持。     

毛诃子化学成分和药理作用的研究进展及其质量标志物（Q-Marker）预测分析

毛诃子Terminaliae Belliricae Fructus为藏族习用药材,在传统中医药以及多民族医药中使用广泛且悠久。现代研究表明毛诃子主要含有酚酸类、鞣质类、黄酮类、萜类、甾体类、木脂素类等化学成分,具有保肝、降血糖、调血脂与抗肿瘤等药理作用。基于对毛诃子的化学成分及药理作用的归纳总结,结合其质量控制研究现状,从传统药性、传统功效、化学成分可测性及药动学等方面对其质量标志物（quality marker,Q-Marker）进行预测。没食子酸、鞣花酸、柯里拉京、没食子甲酯、诃子鞣酸、单宁酸、奎宁酸、6-姜酚、儿茶素等成分可作为毛诃子的主要Q-Marker,以期为毛诃子进一步研究及质量标准的合理建立提供参考。     

基于UPLC-Q-TOF-MSE结合多元统计方法的不同产地白芍药材质量评价

目的 分析不同产地白芍药材质量差异及特异性化学成分,为白芍的产地判别和质量评价提供依据。方法 采用超高效液相色谱-四极杆飞行时间串联质谱(UPLC-Q-TOF-MS^E)对不同产地白芍样品全成分分析,应用主成分分析(principal component analysis,PCA)、正交偏最小二乘法-判别分析(orthogonal partial least squares-discriminant analysis,OPLS-DA)及聚类分析(cluster analysis,CA)对安徽亳州、四川中江、浙江磐安3个产地共15批次白芍药材进行多元统计分析,根据VIP值>1和t检验(P<0.05)筛选不同产地白芍药材中具有显著差异的化学成分。结果 从不同产地白芍药材中共鉴定出44个化学成分,以单萜类、鞣质类、三萜类、黄酮类、挥发油类等成分为主,其中以单萜类成分含量最高。不同产地白芍的化学成分差异明显,共鉴定出16个差异化学成分,其中牡丹皮苷G为安徽亳州产地特有成分,1,2,3,6-四-O-没食子酰-β-D-葡萄糖为浙江磐安产地的特有成分,1-O-β-D-...     

The medicinal chemistry of tea

The medicinal effects of tea (Camellia sinensis) have a long, rich history. The first references to tea date back nearly 5,000 years and are justifiably obscure. Tea has been consumed literally for thousands of years, and it is this long safety record of tea consumption that makes these compounds an attractive target for drug discovery. Much attention has been focused on the role of tea flavanoids in the promotion of health in recent years. However, future studies will need to clarify further the mechanisms of action of these and related compounds, as well as their absorption, metabolism, and potential toxicity. We review here some of the currently available information pertaining to the chemistry, synthesis, pharmacokinetics, and pharmacodynamics of these compounds, which will hopefully serve as a starting point for the continued investigation of these compounds in the clinical setting. Drug Dev. Res. 61:45–65, 2004. © 2004 Wiley‐Liss, Inc.     

(–)-Epicatechin gallate serves as a novel new delhi metallo-β-lactamase-1 (NDM-1) inhibitor

The β-lactam antibiotic resistance caused by NDM-1 has become a major crisis of global public health. We have previously screened out (–)-epicatechin gallate (ECG) as a potent NDM-1 inhibitor. We further discussed its inhibitory effect and action mode in the present study. According to our results, ECG reversibly inactivated NDM-1 in a non-competitive mode, with an IC₅₀ value of 4.48 μM. ECG effectively recovered the activity of several β-lactam antibiotics against resistant strain harboring blaNDM-1. Especially, the effects on carbapenems were worth mentioning. The zinc supplement assay indicated a zinc-related mechanism of ECG. Different from traditional chelating agents, it showed low toxicity both in vivo and in vitro. In a word, our findings provided a promising NDM-1 inhibitor, ECG, which was able to assist carbapenems against NDM-1-producing strain.     

Great green tea ingredient? A narrative literature review on epigallocatechin gallate and its biophysical properties for topical use in dermatology

The purpose of this review is to examine epigallocatechin‐3‐gallate (EGCG) regarding its stability in different conditions (pH‐value, concentration, temperature), its interactions with common cosmetic ingredients, and its application in the dermatological field. The literature research considered published journal articles (clinical trials and scientific reviews). Studies were identified by searching electronic databases (MEDLINE and PubMed) and reference lists of respective articles. Higher concentrations of EGCG were reported to correlate with better stability and the same can be said for low temperatures and pH values. The interaction between EGCG and hyaluronic acid strengthens its antioxidant activities. Titanium dioxide coated with EGCG proved a suitable ingredient in sunscreens. The polyphenol possesses antioxidant properties, which proved effective in the prevention of UV‐induced skin damage and to alleviate the symptoms of Imiquimod‐induced psoriasis. The three endpoints of this review not only showed interesting results but also highlighted some limitations of EGCG. Studies show that the molecule is unstable, which may hinder its dermatological and cosmetic applications. The reported interactions with cosmetic ingredients were limited. As the health aspects of EGCG are well‐reported, ECGC has become a focus of interest for health professionals trying to treat common dermatological diseases.