转鼓和搅拌槽反应器中氧化亚铁硫杆菌氧化Fe2+的比较（英文）

研究转鼓和搅拌槽反应器中氧化亚铁硫杆菌在不同Al2O3粉末含量下对Fe2+的氧化。结果表明:未添加Al2O3粉末时,氧化亚铁硫杆菌在搅拌槽中的生物活性比在转鼓中的生物活性高。当Al2O3粉末含量从0增加到50%(质量分数)时,Fe2+的生物氧化速率从0.23g/(L·h)显著降低到0.025g/(L·h),可能是搅拌槽中的固体颗粒碰撞和研磨作用导致氧化亚铁硫杆菌失活。转鼓中Al2O3的含量增加对氧化亚铁硫杆菌的生物活性仅有较小的负面影响,这是由于两个反应器不同的混合机制所致。在相同的Al2O3含量下,Fe2+在转鼓反应器中的生物氧化速率比在搅拌槽中的生物氧化速率更高,尤其在较高的固体含量下,表明转鼓反应器能允许较高的固体含量和维持较高的生物活性。由于Al2O3粉末与真实硫化矿具有不同的物理化学性质,因此转鼓反应器用于硫化矿生物浸出的可行性还需进一步验证。     

Mesoporous electroactive silver doped calcium borosilicates: Structural,antibacterial and myogenic potential relationship of improved bio-ceramics

In this work improved electroactive mesoporous Ag-doped bio-ceramics for medical usages are developed, examining their structural, electrical, in-vitro bioactivity, cell cultures and antibacterial properties against various classical pathogenic bacteria. Ag-containing mesoporous bio-ceramics (MBCs): xmol%Ag₂O - (100-x)[45.8CaO-8.4B₂O₃-45.8SiO₂] where x = 2, 5, 7.5 and 10 were synthesized through a sol-gel method. The small angle X-ray scattering and electron microscopy studies reveal the embedment of silver nanoparticles in the samples. Existence of silver as Ag⁺/Ag⁰ forms in the samples is confirmed by X-ray photoelectron spectroscopy. The N₂ adsorption-desorption analysis evidence the mesoporous structure of the samples. The electrical conductivity of samples increases from 5.4 x 10^?8 S cm^?1 for x = 2 to 1.9 x 10^?6 S cm^?1 for x = 7.5 and then decreases to 0.9 x 10^?6 S cm^?1 for x = 10 at 110 °C. In vitro bioactivity studies revealed that Ag-containing MBCs hold the bone-like hydroxyapatite formation after immersion in human blood plasma like-solution such as Dulbecco's Modi?ed Eagle's Medium. The antibacterial effect of samples against pathogenic bacteria (S. aureus, E. coli, P. monas aeruginosa, and B. cereus) increases with Ag concentration (x = 7.5) and then decreases with Ag content (x = 10). Antibacterial effect is greater for the sample with high electrical conductivity. The cell culture studies evidence not considerable cytotoxic effects for Ag-containing MBCs. Finally, the C2C12 myoblast cell culture studies reveal the significant cell growths and differentiation (myogenesis) for high electrical conducting Ag-containing MBCs.     

Polymer–Ferrocene Conjugates Containing an Ester Function in the Connecting Links

Ferrocene, the parent of the metallocene family of organotransition metal compounds, has come to occupy a significant niche in cancer research. Developmental work in the authors' laboratory has been focused on the synthesis of antiproliferative ferrocene conjugates in which the bioactive ferrocene unit is covalently, yet bioreversibly bound (anchored) to water-soluble carrier polymers designed in accordance with requisite biomedical specifications. The anchoring link in most of these conjugates has been an aliphatic spacer containing the biofissionable amide group. In this communication the synthesis of a class of ferrocene conjugates is reported in which the ferrocene group is carrier-anchored through spacers containing an ester link, of interest here because of potentially different drug release behavior. The carriers are polyamides equipped with variously spaced hydroxyl side groups, to which the ferrocenylation agent, 4-ferrocenylbutanoic acid, is connected through esterification. The coupling reactions, mediated by carbodiimide agent and catalyzed by 4-(dimethylamino)pyridine, are carried out in DMF at temperatures not exceeding 65°C, and the water-soluble product polymers are isolated in yields of typically 70–85% by precipitation, aqueous dialysis, and freeze-drying. With the molar feed ratios chosen in these coupling experiments, the incorporation of ferrocene, assessed by ¹H NMR spectroscopy, corresponds to iron contents of roughly 2.5–5.5%, by mass. The conjugates will be included in a forthcoming bioactivity screening program.     

氟磷灰石-氟金云母微晶玻璃的生物活性研究

通过模拟细胞外液浸泡及动物骨内种植的方法研究了氟磷灰石-氟金云母微晶玻璃的生物活性机理。借助于SEM/EDAX,薄膜XRD,IRRS及原子吸收光谱分析等技术,研究了该微晶玻璃在生理环境中表面羟墓碘灰石层的形成过程。根据微晶玻璃中主晶相种类、显微结构特点及溶液中各离子的浓度等讨沦了羟基碑灰石层的形成机理。认为微晶玻璃中残余玻璃相的Ca~(2+)溶出及溶液相对于羟基磷灰石的过饱和状态,对材料表面羟基碑灰石层的形成具有重要意义。形成的羟基磷灰石层具有较低的结晶度,它是由最初的无定形态含水富CaO,P_2O_5薄层晶化转变而成。     

微振动应力环境影响羟基磷灰石陶瓷生物活性及力学稳定性的体外评价

本研究考察微振动应力环境(MVS)下羟基磷灰石(HA)陶瓷的生物活性及力学稳定性, 探讨体内生理应力环境对HA陶瓷骨诱导性的影响。扫描电子显微镜(SEM)和钙离子释放结果均显示, MVS有利于具有较高微孔隙率((29±1.2)%, (26.4±0.3)%)HA材料的钙离子再沉积和类骨磷灰石层形成, 而对于微孔隙率较低((10.6±0.8)%)的HA材料则促进其钙离子释放。蛋白吸附结果显示40 Hz的MVS促进了HA的蛋白吸附, 60 Hz的MVS则显著抑制HA的蛋白吸附行为。抗压试验表明MVS应力环境并未影响HA多孔支架的力学稳定性。研究表明应力环境是影响HA陶瓷生物活性和骨诱导性的重要因素。     

电压对钛表面微弧氧化陶瓷层特性的影响

为了提高钛表面的生物活性,利用微弧氧化技术在钛表面制备了含有钙磷的多孔二氧化钛陶瓷层。研究了施加电压对多孔微弧氧化层的平均孔径、表面粗糙度、相成分、钙磷含量以及Ca/P原子比的影响。结果表明,随着微弧氧化电压的升高,平均孔径、表面粗糙度、膜层中钙磷含量以及Ca/P原子比都逐渐增大,膜层的相成分由锐钛矿逐渐向金红石转变,并且膜层中逐渐有羟基磷灰石生成。     

双核铜(Ⅱ)-β-丙氨酸缩水杨醛席夫碱配合物的合成及其性质

以β-丙氨酸、水杨醛和乙酸铜为原料在乙醇溶液中合成了双核铜(Ⅱ)-β-丙氨酸缩水杨醛席夫碱配合物[Cu2(β-ala-sala)2.H2O].H2O,采用元素分析、IR、紫外光谱、热重分析对其结构进行了表征.分别用循环伏安法和抗菌活性实验研究了配合物的电化学性质和抗菌活性,结果表明:该配合物的电化学行为是一个不可逆过程,且具有比青霉素更好的抗菌活性.     

紫杉醇构效关系及类似物生物活性的研究进展

紫杉醇是当今最有效的抗癌药物之一.它的作用机理独特,通过诱导和促进微管蛋白聚合形成稳定结构,从而抑制微管解聚.对紫杉醇的构效与活性之间的关系以及近十年来紫杉醇类似物研究进展进行了比较详尽的阐述,包括以下几个方面:C2位苯甲酰基、C4位乙酰基、D环、C13侧链、C2与C3′成环、C4与C3′成环以及其它位基团对紫杉醇生物活性的影响.从紫杉醇的构效关系看,C1、C7、C9和C10位基团对它的生物活性并无太大的影响,但是C2、C4位的基团以及D环和C13位的侧链对紫杉醇的生物活性影响重大.     

一种基于进化学习的中药定量组效关系建模方法

针对中药的组分配伍优化设计，提出一类中药药效智能预测及定量组效关系（QCAR）建模方法.采用全新设计的自适应浮点编码遗传算法，并与反向传播（BP）算法集成用于神经网络学习训练，既改善了神经元网络获得全局最优解的能力，又消除了经典遗传算法（GA）在编码与解码时产生的截断误差，从而提高了QCAR模型的训练与预报精度.以中药当归为实例对该方法进行应用研究.结果表明，无论是交叉验证还是独立检验均取得较好效果，明显优于常规建模方法，可用于对中药药效进行智能预测     

Enhancement Effect of Gold Nanoparticles on the Bioactivity of Hydrogen-producing Microbe

1 IntroductionGold nanoparticles have attracted considerable atten-tionin manyfields duetotheir some special properties al-though goldis very popularfor beingchemicallyinert[1-3].For example ,gold nanoparticles as amplificationtags havebeenthe subject of research directed at gene analysis[4]and antibody or antigen detection[5-7]due to the large di-electric constant ,ease of preparation,andits biocompati-bility[8].Nanoparticles in the range of 1-10 nmin diameterwould display electronic structur…