丝瓜叶中丝瓜皂甙R的化学结构

从丝瓜(Lufa cylindrica Roem.)叶中分得一种新的五环三萜皂甙和丝瓜皂甙G,用光谱和化学方法确定新皂甙的结构为2α,21β-二羟基常春藤皂甙元-3-O-β-D-吡喃葡萄糖甙,命名为丝瓜皂甙R。     

Cytotoxic and Apoptotic Effects of Luffa Cylindrica Leaves Extract against Acute Lymphoblastic Leukemic Stem Cells

Background: Acute lymphoblastic leukemia (ALL) is an aggressive malignancy defined by accumulation of lymphoblasts in the bone marrow. Leukemic stem cells (LSCs) are the major cause of the recurrence and metastasis of ALL. This study aimed to develop an effective anti-cancer agent targeting these LSCs. Luffa Cylindrica (L.C.) leaves extract was selected to evaluate its effect on ALL via eradicating the LSCs as it contains many active anti-cancer flavonoids. Methods: Thirty-two bone marrow samples of ALL patients were used in this study. LSCs population was identified in the selected samples. Cell viability was measured by MTT assay and flow cytometry. Cell cycle, apoptosis, proliferation marker; ki-67 and colony forming assay were further analyzed. Results: This study revealed the expression of CD34+/CD38+ cells in addition to CD34+/CD38- population and the extract was effective against the two LSCs populations. MTT assay showed that treated leukemic cells exhibited significant reduction in the viable cells in a dose dependent manner with IC50 of 3 µg/µl which was then confirmed by flow cytometry. Cell cycle analysis results showed significant reduction in the percentage of cells treated with L.C. extract in both the S and G0/G1 phases, with concomitant increase in the G2/M phase. Also, L.C. extract could effectively induce apoptosis, inhibit proliferation and suppress colonogenecity of leukemic cells. Conclusion: This study validated the medicinal potential of L.C. leaves extract as a promising anti-leukemic agent targeting both LSCs and blasts in ALL patients, which may be explained by the synergy found between its potent flavonoids especially apigenin, luteolin and kaempferol.     

Novel multilayer meniscal scaffold provides biomechanical and histological results comparable to polyurethane scaffolds: An 8 week rabbit study

ObjectiveThe aim of this study was to evaluate the meniscal regeneration and arthritic changes after partial meniscectomy and application of either polyurethane scaffold or novel multilayer meniscal scaffold in a rabbit model.MethodsSixteen NewZealand rabbits were randomly divided into three groups. A reproducible 1.5-mm cylindrical defect was created in the avascular zone of the anterior horn of the medial meniscus bilaterally. Defects were filled with the polyurethane scaffold in Group 1 (n:6) and with novel multilayer scaffold in Group 2 (n:6). Rabbits in Group 3 (n:4) did not receive any treatment and defects were left empty. All animals were sacrificed after 8 weeks and bilateral knee joints were taken for macroscopic, biomechanical, and histological analysis. After excision of menisci, inked condylar surfaces and tibial plateaus were evaluated for arthritic changes. Digital photographs of excised menisci were also obtained and surface areas were measured by a computer software. Indentation testing of the tibial condyles and compression tests for the relevant meniscal areas was also performed in all groups. Histological analysis was made and all specimens were scored according to Rodeo scoring system.ResultsNo signs of inflammation or infection were observed in any animals. A significant difference was observed between meniscus surface areas of the multilayer scaffold group (20.13 ± 1.91 mm²) and the group with empty meniscus defects (15.62 ± 2.04 mm²) (p = 0.047). The results of biomechanical compression tests revealed a significant difference between the Hayes scores of the second group (1.728) and the empty defect group (0,467) (p = 0.029). Intact meniscal tissue showed higher mechanical properties than all the defected samples. Multilayer scaffold group demonstrated the closest results compared to healthy meniscus tissue. Tibia indentation tests and histological evaluation showed no significant differences between groups (p = 0.401 and p = 0.186 respectively).ConclusionsIn this study, the initial evaluation of novel multilayer meniscal scaffold prevented the shrinkage that may occur in the meniscus area and demonstrated superior biomechanical results compared to empty defects. No adverse events related to scaffold material was observed. Besides, promising biomechanical and histological results, comparable to polyurethane scaffold, were obtained.     

Standardizing Imperata cylindrica—source material for quality allergen preparations

Background: Tropical countries experience wide variations in daytime temperature and relative humidity. This affects the quality of the source material used for allergen extracts. The present study was undertaken to standardize the processing and preservation conditions of Imperata cylindrica grass pollen. Methods: I. cylindrica (Ic) inflorescence were freeze-dried, pollens sieved out and stored at −70 °C (IcA). Alternatively, the inflorescence were dried at room temperature and then at 37 °C, pollens sieved out and stored at 4 °C (IcB). The extracts prepared in PBS were analyzed in vivo by skin tests and in vitro by immunochemical methods. Results: Reduced SDS-PAGE revealed 37 protein bands in IcA extract and 23 in IcB extract. IgE immunoblot with a pool of sera from Ic hypersensitive patients showed 30 allergenic bands in IcA and 14 in IcB. Immunoblot using anti-Ic rabbit sera revealed 33 antigenic bands in IcA and 22 in IcB. In both blots, the IcA extract exhibited sharp bands and the IcB extract exhibited diffuse bands. ELISA, ELISA inhibition and skin test procedures showed that IcA extracts had a higher potency than IcB extracts. Conclusions: Extracts prepared from −70 °C processed and preserved pollens (IcA) are allergenically more potent and contain a greater number of major and minor allergens than IcB extracts.     

薄层色谱法对水和乙醇作丝瓜根成分提取溶剂的比较研究

筛选出分离效果优于文献的展开剂，分别用水和乙醇作溶剂提取丝瓜根成分，作薄层色谱，以薄层色谱上的斑点作指标成分进行比较。结果表明，水可以代替乙醇作为丝瓜根成分的提取溶剂。     

丝瓜籽核糖体失活蛋白luffin-a基因的克隆和表达

目的:从丝瓜籽中克隆HIV整合酶抑制剂luffin-a基因,并构建其表达载体.方法:根据报道的cDNA序列,用RT-PCR的方法从未成熟的丝瓜籽中克隆luffin-a基因,T-A克隆后鉴定核苷酸序列.构建表达载体pET-44a( )-luffin-a,转化大肠杆菌BL21(DE3),并经IPTG诱导表达.用透析法对包含体复性;SDS-PAGE鉴定luffin-a表达产物,用MTT法分析其生物学活性.结果:克隆的luffin-a基因与国外报道的核苷酸序列同源性为99.73%,其所编码的氨基酸序列完全一致.经SDS-PAGE分析:luffin-a主要存在于包含体中.MTT法测定:复性后蛋白具有与蓖麻毒素A链相似的细胞毒性.结论:本研究成功地构建了luffin-a的表达系统,所表达蛋白经复性后具有生物学活性.     

星点设计-效应面法优化白茅根总酚酸提取工艺

目的 优化白茅根总酚酸的提取工艺.方法 采用超声波辅助提取法,选取提取试剂浓度、提取时间、提取温度和料液比作单因素试验,在此基础上采用星点设计考察提取试剂浓度、提取时间及提取温度3因素对提取工艺的影响,对结果进行二项式方程拟合,效应面法筛选最佳条件并进行预测分析.结果 得到的最佳提取工艺条件为乙醇浓度为40％,提取时问38 min,提取温度为33℃,料液比为1:40,总酚酸质量分数的预测值为2.71 mg/g.验证实验的总酚酸质量分数为2.46mg/g,与预测值接近.结论 说明模型可靠.该工艺步骤简单,稳定可行.     

丝瓜提取物抗氧化活性的研究

目的: 分离提取丝瓜抗氧化活性成分,观察其抗氧化效应。方法: 应用溶剂萃取法及葡聚糖凝胶柱层析法分离提取丝瓜抗氧化活性物质,通过测定不同提取物的抗氧化能力,筛选出丝瓜的抗氧化活性成分。结果: 由溶剂萃取法获得丝瓜提取物Ⅱ、Ⅲ、Ⅳ、Ⅴ,其中提取物Ⅲ抑制DPPH·和OH·自由基效果显著。提取物Ⅲ经柱层析进一步分离,得到A、B、C、D、E5种组分,其中组分D、E抑制DPPH·和OH·自由基效果最显著,经鉴定提取物符合黄酮类物质特性。结论: 丝瓜具有清除自由基的作用,且主要作用物质为黄酮类物质。     

安徽产5种辛夷的生药鉴别

报道了安徽常见的5种辛夷:玉兰Magnolia denudata、淡紫玉兰M. denudata var. dilutipurpurascens、黄山木兰M. cylindrica、紫玉兰M. liliflora和天目木兰M. amoena花蕾的生药性状和显微特征。     

丝瓜水煎液对脾虚便秘小鼠VIP及5-HT含量的影响

目的:观察丝瓜水煎液对脾虚便秘小鼠血清、结肠组织中管活性肠肽(vasoactive intestine Pe Ptide,VIP)和五羟色胺(selective serotonin reu Ptake inhibitors,5-HT)含量的影响。方法:将KM种雄性小鼠(18~22 g)120只分为6组:空白对照组、脾虚模型组、丝瓜水煎液Ⅰ组(2.5 g·kg~(-1))、丝瓜水煎液Ⅱ组(5.0 g·kg~(-1))、丝瓜水煎液Ⅲ组(10 g·kg~(-1))以及西沙必利组(0.005 g·kg~(-1)),每组10只。空白对照组灌胃生理盐水,其余各组小鼠灌胃番泻叶颗粒,灌胃剂量为每只0.4 g,一天2次,自由摄食饮水。第8天起停用番泻叶颗粒,正常对照组小鼠继续灌胃生理盐水,其余各组小鼠控制饮食,釆用饥饱失常方法延续脾虚状态,隔天喂食生大米每只4 g,自由饮水,连续8 d。通过观察发现模型组小鼠造模后出现拱背、消痩,大便数量减少、变硬,即造模成功。实验第16天至第30天,正常对照组、模型组灌胃生理盐水(0.01 m L·g-1),西沙必利组给予西沙必利(0.005 g·kg~(-1)),丝瓜水煎液组分别灌胃给予不同浓度的丝瓜水煎液,灌胃剂量为0.01 m L·kg~(-1)。观察丝瓜水煎液对脾虚便秘小鼠肠蠕动的影响;用酶联免疫吸附法(ELISA)分别测定小鼠血清、结肠组织中VIP及5-HT含量。结果:脾虚便秘模型组小鼠肠推进率,血清、结肠中5-HT、VIP含量都显著降低,与正常对照组相比有显著差异(P0.01或P0.05)。丝瓜水煎液Ⅱ组、丝瓜水煎液Ⅲ组小鼠肠推进率、血清、结肠中5-HT、VIP含量与模型组比较显著升高(P0.01或P0.05)。结论:丝瓜水煎液可以促进脾虚便秘小鼠肠运动,其机制可能与提高小鼠血清、结肠中5-HT、VIP含量有关。