Syntheses and Bioactivity of 4″-Sulfonate-5-triphenylsilyl Avermectin B_(1a) and Ivermectin B_(1a) Derivatives

IntroductionAvermectins occuring in nature are macro-cyclic lactones with important anthelmintic,insec-ticidal and miticidal activities.Avermectins andtheir many analogues,such as ivermectins( 2 2 ,2 3-dihydroavermectin B1) and4″- epi- ( methylamino) -4″- deoxyavermectin B1benzoate[1] ,bind to verte-brates′ and invertebrates′ γ- gaminobutyric acid( GABA ) - gated and invertebrate glutamate- gatedchloride channels to increase ion conductance,thereby disrupting inhibitory or excitatory ac…     

17400鲨鱼软骨血管生成抑制因子的纯化及生物学活性研究

采用盐酸胍抽提、膜超滤、丙酮分级沉淀、Sephadex-75柱层析和C₄反相高效液相色谱等分离步骤,从广东阳江鲨鱼软骨中纯化获得新的鲨鱼软骨血管生成抑制因子SCAI-c(SharkCartilageAngiogenesis In-hibitor-c,SCAI-c);SDS-PAGE电泳银染显示为一条带,根据蛋白质的相对迁移率计算,分子量为17400;它对鸡胚绒毛尿囊膜血管的形成具有显著抑制效应,并有明显的浓度依赖关系.SCAI-c与SCAI-a具有类似的生物学特征.     

Microstructure: Surface and cross-sectional studies of hydroxyapatite formation on the surface of white Portland cement paste in vitro

The formation of hydroxyapatite was investigated at the surface and at the cross-section of white Portland cement paste samples before and after immersion in simulated body fluid. Scanning electron microscope images showed that hydroxyapatite were found at the surface of white Portland cement after immersion in simulated body fluid. Hydroxyapatite grains of mostly ≈1 μm size with some grain size of ≈2-3 μm were seen after 4 days immersion period. More estabilshed hydroxyapatite grain size of ≈3 μm grains were observed at longer period of immersion at 7 and 10 days. The cross-section of the samples was investigated using line scanning technique and was used to determine the hydroxyapatite layer. A strong spectrum of phosphorus is detected up to 6-8 μm depth for samples after 4, 7 and 10 days immersion in simulated body fluid when compared to weak spectrum detected before immersion. The increase in the phosphorus spectrum corresponds to the hydroxyapatite formation on the surface of the samples after the samples were placed in simulated body fluid.     

Recent Progress on the Synthesis and Bioactivity of Marine Naturally Occurring Dienamides and Related Derivatives

The diverse biological activities of many marine naturally occurring dienamides have made them privileged structures for the development of new drugs. This review highlights the different synthetic approaches for the preparation of the marine naturally occurring dienamides and related pharmaceutically active derivatives.     

Lycopodium japonicum: A comprehensive review on its phytochemicals and biological activities

Lycopodium japonicum Thunb (Lycopodiaceae) is a common and abundant plant widely distributed in China, Japan and countries of Southern Asia and used in traditional Chinese medicine for the treatment of sprains, strains and myasthenia. This review focuses on the phytochemicals and biological actions, with the objective of stimulating further studies on the plant. 132 chemical compounds have been identified and isolated from this plant, and the most important are alkaloids and serratane triterpenoids. The isolated compounds of L. japonicum were shown to possess acetylcholinesterase inhibitory, cytotoxic, anti-inflammatory, anti-HIV-1 and α-glucosidase inhibitory activities. Further studies should be carried out on this plant in order to disclose many more active principles and mechanisms of active components.     

Synergistic effect of T80/B30 vesicles and T80/PN320 mixed micelles with Se/C on nasal mucosal immunity

Selenium doped carbon (Se/C), an easily fabricated material, was found to be bio-active and it can serve as an adjuvant to enhance the immune effect of Tween 80/Brij 30 (T80/B30) vesicles and Tween 80/polymer cationic surfactant PN320 (T80/PN320) mixed micelles. The synergistic effect of the combination of T80/B30 vesicles and T80/PN320 mixed micelles with Se/C on nasal mucosal immunity was studied in this work, which might provide theoretical basis for developing the related new adjuvant for nasal immunization of recombinant protein, peptide and split protein vaccine. Since both selenium and carbon were bio-compatible elements, Se/C might be safe for practical applications, and this was also reflected by the low hemolytic activity of the materials. This work not only reports an efficient protocol for adjuvant development, but also significantly expands the application scope of selenium chemistry.     

A new isobenzofuranone derivative from a marine Streptomyces sp.

One new isobenzofuranone derivative,1,4-dimethoxy-3-(3R*-hydroxy-3R*-methyl-1-tetralone)-1(3H)-isobenzofuran(1),was isolated from the broth of marine Streptomyces sp.M268.The structure was elucidated by spectroscopy characteristics as well as comparison with the literature.Compound 1 exhibited cytotoxicities against human cancer cell,HL-60,A549,and BEL-7402.     

The interactions of metal ions with nonsteroidal anti-inflammatory drugs (oxicams)

Much work has been focused on interactions of metal ions with nonsteroidal anti-inflammatory drugs (oxicams). Numerous attempts to synthesize several metal complexes have been published. This review highlights the synthesis and properties of the synthesized metal complexes. Different physico-chemical methods (IR, UV–Vis, measurement, thermal analysis, and NMR spectroscopy) as well as the bioactivity of the metal compounds are mentioned.     

Correlation between bioactivity and structural properties of titanium dioxide coatings grown by atomic layer deposition

TiO₂ coatings were grown on Ti and Si by Atomic Layer Deposition (ALD) from titanium ethoxide and water at 300 °C in a wide range of the reaction cycles number N = 100-2000. TiO₂ coatings were found to be amorphous at low value of N < 300 while the coatings grown at N ≥ 300 revealed anatase polycrystalline structure. The TiO₂ coatings bioactivity was evaluated by hydroxyapatite forming ability by the technique of soaking in Simulated Body Fluid (SBF). Correlation between bioactivity and structural properties of TiO₂ was determined. X-ray diffraction and scanning electron microscopy with electron probe microanalysis showed that amorphous TiO₂ coating did not induce the hydroxyapatite growth whereas anatase resulted in the hydroxyapatite forming on the samples surfaces which confirmed TiO₂ anatase bioactivity.     

Isolation,Purification and Bioactivities of Polysaccharides from Irpex lacteus

Irpex lacteus has been widely used for treating chronic glomerulonephritis as a traditional Chinese medicine.Seven water-soluble polysaccharide fractions(ILN Ⅰ,ILN Ⅱ,ILN Ⅲ,ILA Ⅰ,ILA Ⅱ,ILB Ⅰ and ILB Ⅱ)w...