第三代铂抗癌药物研究评论

本文评论顺铂和卡铂之后的第三代铂抗癌药物的研究状况。报道其配合物的抗肿瘤活性、限量毒性、交叉耐药性和其中四种配合物的Ⅱ期临床结果。这些配合物的总体水平并不优于顺铂和卡铂。研究抗癌机理与顺铂和卡铂不同的新型铂配合物是增加该类药物的抗肿瘤活性和克服交叉耐药性的途径之一。     

含稳定氮氧自由基结构的铂配合物的合成和结构及体外抗癌活性的初步研究

合成并表征了一种新的未见文献报道的铂配合物。用元素分析、红外光谱、紫外光谱、质谱、差热分析等手段表征了该配合物。体外抑癌实验表明该配合物具有抗癌活性。     

新型铂(Ⅱ)类配合物的合成、表征和抗肿瘤活性

合成了以甲胺/环戊胺为伴随基团,分别以氯离子、1,1-环丁基二羧酸根和草酸根作为离去基团的3种新的铂(II)配合物。以顺-二碘-二环戊胺合铂(II)、硝酸银、甲胺、氯化钾、1,1-环丁基二羧酸钾和草酸钾为原料合成目标化合物。采用元素分析、质谱、核磁共振氢谱和红外光谱分析其组成和结构,利用MTT体外检测法进行了初步的体外活性评价,表明合成的3种化合物结构与理论一致,具有一定的体外肿瘤生长抑制活性。     

金属类抗癌药物研究新进展

<正>金属配合物的药用性引起了人们的广泛关注,开辟了金属配合物抗癌药物研究的新领域。随着人们对金属配合物的药理作用认识的进一步深入,新的高效、低毒、具有抗癌活性的金属化合物不断被合成出来。其中,包括某些有机铂类化合物、有机锡配合物、有     

铂类抗癌药物展望

在过去的10年里,铂类抗癌药物取得了重要的进展,又有4种新药,奈达铂、奥沙利铂、舒铂和洛铂相继于1995～2001年成功上市,同时也有多个候选药物因疗效低、毒性大,与顺铂、卡铂比较无优势而在临床试验中被淘汰。目前还有另外9种铂化合物仍在进行临床研究,这些化合物为顺铂和卡铂的类似物、亲脂性配合物、口服铂(Ⅳ)配合物、多核铂配合物以及具有空间位阻的铂配合物。新的铂类抗癌药将在今后10～20年内从那些在临床研究中显示出低毒性、抗癌谱广、与现有药物无交叉耐药性的化合物中产生。     

顺式-甲基丙二酸-二氨合铂(II)的合成、表征及抗癌活性

为合成新的铂配合物顺式-甲基丙二酸-二氨合铂(II),以顺式二碘-二氨合铂(II)为起始原料,先后与硝酸银和甲基丙二酸反应合成目标化合物。采用元素分析、质谱、核磁共振氢谱和红外光谱分析其组成和结构,采用MTT法对配合物进行了初步的体外活性评价。结果显示合成的化合物结构与理论一致,具有一定的体外肿瘤生长抑制活性。     

[Pt(en)(5-Fu)2]Cl2配合物的合成及抗肿瘤活性

为寻求高效低毒的新型顺铂类抗肿瘤药物,用K2PtCl4、乙二胺(en)、氟尿嘧啶(5-Fu)为原料,设计合成了顺铂类似物[Pt(en))(5-Fu)2]Cl2配合物,由元素分析、红外光谱和质谱分析初步证实了其化学结构,用改良MTT、SRB法,选用K562、A549、Bel-7402、BIU-87、Bcap-37细胞株对其进行体外抗肿瘤活性测定。结果表明,所合成的配合物除在浓度为0．01、0．1／μg／mL时对K562细胞株抗肿瘤活性大于顺铂和氟尿嘧啶外,其它情况下的抗肿瘤活性均小于顺铂和氟尿嘧啶。该配合物仍有进一步研究的价值。     

一种离子型黄光铱配合物的合成、表征及性能研究

在温和的反应条件下，以2,4-二氟苯硼酸、2-氯喹啉为原料合成了一种新型离子型铱配合物，通过元素分析、红外光谱、¹H-NMR、质谱以及X单晶衍射对产物进行了结构表征。并考察了配合物的光物理性能和热稳定性能。结果表明配合物单晶结构为扭曲的八面体构型，属于三斜晶系，空间群为P-1；配合物最大发射波长为542 nm，CIEx, y坐标为(0.41, 0.57)，是一种新型的黄色发光的离子型铱磷光配合物。     

顺式-没食子酸-氨,2-甲基吡啶合铂(Ⅱ)的合成、表征及抗肿瘤活性

为合成新的铂配合物顺式-没食子酸-氨,2-甲基吡啶合铂(Ⅱ),以氯亚铂酸钾为起始原料,先后与碘化钾、2-甲基吡啶、氨水、硝酸银和没食子酸反应合成目标化合物。采用元素分析、质谱、核磁共振氢谱和红外光谱分析其组成和结构,利用MTT体外检测法进行了初步的体外活性评价。结果显示合成的化合物结构与理论值一致,具有一定的体外肿瘤生长抑制活性。     

甲基丙二酸-(反式-1,2-二甲胺基环丁烷)合铂(II)的合成、结构及抗肿瘤活性

通过水解法合成了甲基丙二酸-(反式-1,2-二甲胺基环丁烷)合铂(Ⅱ)。采用元素分析、质谱(ESI-MS)、红外光谱(IR)和核磁共振氢谱(¹H NMR)确证了该配合物的组成和化学结构。采用MTS法评价其抗肿瘤活性,发现该配合物对常见5种癌细胞的生长有明显的抑制活性。     

Effects of Post-weld Heat Treatment on Microstructure,Mechanical Properties and the Role of Weld Reinforcement in 2219 Aluminum Alloy TIG-Welded Joints

In as-welded state, each region of 2219 aluminum alloy TIG-welded joint shows diff erent microstructure and microhardness due to the diff erent welding heat cycles and the resulting evolution of second phases. After the post-weld heat treatment, both the amount and the size of the eutectic structure or θ phases decreased. Correspondingly, both the Cu content in α-Al matrix and the microhardness increased to a similar level in each region of the joint, and the tensile strength of the entire joint was greatly improved. Post-weld heat treatment played the role of solid solution strengthening and aging strengthening. After the post-weld heat treatment, the weld performance became similar to other regions, but weld reinforcements lost their reinforcing eff ect on the weld and their existence was more of an adverse eff ect. The joint without weld reinforcements after the post-weld heat treatment had the optimal tensile properties, and the specimens randomly crack in the weld zone.     

The First Phase of the SRIF Industrialized Base in ＂West Area＂ Has Been Put into Operation

After nearly two years＇ tense construction, the first phase of industrialized base of Shenyang Research Institute of Foundry （SRIF）, located at the Tiexi Casting and Forging Industrial Park in the west of Tiexi District, has now been completed and formally put into operation.     

Thermodynamics Study on the Decomposition of Chromite with KOH

Institute of Process Engineering, Chinese Academy of Sciences, China, has proposed a method for oxidative leaching of chromite with potassium hydroxide. Understanding the mechanism of chromite decomposition, especially in the potassium hydroxide fusion, is important for the optimization of the operating parameters of the oxidative leaching process. A traditional thermodynamic method is proposed and the thermal decomposition and the reaction decomposition during the oxidative leaching of chromite with KOH and oxygen is discussed, which suggests that chromite is mainly destroyed by reactions with KOH and oxygen. Meanwhile, equilibrium of the main reactions of the above process was calculated at different temperatures and oxygen partial pressures. The stable zones of productions, namely, K2CrO4 and Fe2O3, increase with the decrease of temperature, which indicates that higher temperature is not beneficial to thermodynamic reactions. In addition, a comparison of the general alkali methods is carried out, and it is concluded that the KOH leaching process is thermodynamically superior to the conventional chromate production process.     

Influence of Heat Treatment on Damping Behaviour of the Magnesium Wrought Alloy AZ61

The effect of isochronal heat treatments for 1h on variation of damping, hardness and microstructural change of the magnesium wrought alloy AZ61 was investigated. Damping and hardness behaviour could be attributed to the evolution of precipitation process. The influence of precipitation on damping behaviour was explained in the framework of the dislocation string model of Granato and Lücke.     

Effect of Rare Earth Doping on Impedance,Modulus and Conductivity Properties of Multiferroic Composites:0.5(BiLa_xFe_(1-x)O_3)–0.5(PbTiO_3)

The Lanthanum-doped bismuth ferrite–lead titanate compositions of 0.5(Bi LaxFe1-xO3)–0.5(Pb Ti O3)(x = 0.05,0.10,0.15,0.20)(BLxF1-x-PT) were prepared by mixed oxide method.Structural characterization was performed by X-ray diffraction and shows a tetragonal structure at room temperature.The lattice parameter c/a ratio decreases with increasing of La(x = 0.05–0.20) concentration of the composites.The effect of charge carrier/ion hopping mechanism,conductivity,relaxation process and impedance parameters was studied using an impedance analyzer in a wide frequency range(102–106Hz) at different temperatures.The nature of Nyquist plot confirms the presence of bulk effects only,and non-Debye type of relaxation processes occurs in the composites.The electrical modulus exhibits an important role of the hopping mechanism in the electrical transport process of the materials.The ac conductivity and dc conductivity of the materials were studied,and the activation energy found to be 0.81,0.77,0.76 and 0.74 e V for all compositions of x = 0.05–0.20 at different temperatures(200–300 °C).     

Quantitative Analysis of the Crystallographic Orientation Relationship Between the Martensite and Austenite in Quenching–Partitioning–Tempering Steels

The orientation relationships(ORs)between the martensite and the retained austenite in low-and medium-carbon steels after quenching–partitioning–tempering process were studied in this work.The ORs in the studied steels are identified by selected-area electron diffraction(SAED)as either K–S or N–W ORs.Meanwhile,the ORs were also studied based on numerical fitting of electron backscatter diffraction data method suggested by Miyamoto.The simulated K–S and N–W ORs in the low-index directions generally do not well coincide with the experimental pole figure,which may be attributed to both the orientation spread from the ideal variant orientations and high symmetry of the low-index directions.However,the simulated results coincide well with experimental pole figures in the high-index directions{123}_(bcc).A modified method with simplicity based on Miyamoto’s work was proposed.The results indicate that the ORs determined by modified method are similar to those determined by Miyamoto’method,that is,the OR is near K–S OR for the low-carbon Q–P–T steel,and with the increase of carbon content,the OR is closer to N–W OR in medium-carbon Q–P–T steel.     

Using Finite Element and Contour Method to Evaluate Residual Stress in Thick Ti-6Al-4V Alloy Welded by Electron Beam Welding

This work was to reveal the residual stress profile in electron beam welded Ti-6Al-4V alloy plates(50 mm thick) by using finite element and contour measurement methods.A three-dimensional finite element model of 50-mmthick titanium component was proposed,in which a column–cone combined heat source model was used to simulate the temperature field and a thermo-elastic–plastic model to analyze residual stress in a weld joint based on ABAQUS software.Considering the uncertainty of welding simulation,the computation was calibrated by experimental data of contour measurement method.Both test and simulated results show that residual stresses on the surface and inside the weld zone are significantly different and present a narrow and large gradient feature in the weld joint.The peak tensile stress exceeds the yield strength of base materials inside weld,which are distinctly different from residual stress of the thin Ti-6Al-4V alloy plates presented in references before.     

Microstructures and Tensile Properties of Ultrafine-Grained Ni–(1–3.5) wt% SiC_(NP) Composites Prepared by a Powder Metallurgy Route

Silicon carbide nanoparticle-reinforced nickel-based composites(Ni–Si CNP),with a Si CNPcontent ranged from1 to 3.5 wt%,were prepared using mechanical alloying and spark plasma sintering.In addition,unreinforced pure nickel samples were also prepared for comparative purposes.To characterize the microstructural properties of both the unreinforced pure nickel and the Ni–Si CNPcomposites transmission electron microscopy(TEM) was used,while their mechanical behavior was investigated using the Vickers pyramid method for hardness measurements and a universal tensile testing machine for tensile tests.TEM results showed an array of dislocation lines decorated in the sintered pure nickel sample,whereas,for the Ni–Si CNPcomposites,the presence of nano-dispersed Si CNPand twinning crystals was observed.These homogeneously distributed Si CNPwere found located either within the matrix,between twins or on grain boundaries.For the Ni–Si CNPcomposites,coerced coarsening of the Si CNPassembly occurred with increasing Si CNPcontent.Furthermore,the grain sizes of the Ni–Si CNPcomposites were much finer than that of the unreinforced pure nickel,which was considered to be due to the composite ball milling process.In all cases,the Ni–Si CNPcomposites showed higher strengths and hardness values than the unreinforced pure nickel,likely due to a combination of dispersion strengthening(Orowan effects) and particle strengthening(Hall–Petch effects).For the Ni–Si CNPcomposites,the strength increased initially and then decreased as a function of Si CNPcontent,whereas their elongation percentages decreased linearly.Compared to all materials tested,the Ni–Si CNPcomposite containing 1.5% Si C was found more superior considering both their strength and plastic properties.     

Directional Growth of Tin Crystals Controlled by Combined Solute Concentration Gradient Field and Static Magnetic Field

A new method was introduced to achieve directional growth of Sn crystals. Microstructures in liquid(Pb)/liquid(Sn) diffusion couples were investigated under various static magnetic fields. Results show that the β-Sn crystals mainly reveal an irregular dendritic morphology without or with a relatively low static magnetic field(B0.3 T). When the magnetic field is increased to 0.5 T, the β-Sn dendrites close to the final stage of growth begin to show some directional character. With a further increase in the magnetic field to a higher level(0.8–5 T), the β-Sn dendrites have an enhanced directional growth character, but the dendrites show a certain deflection. As the magnetic field is increased to 12 T, the directional growth of the β-Sn dendrites in the center of the couple is severely destroyed. The mechanism of the directional growth of the β-Sn crystals and the deflection of the β-Sn crystals with the application of static magnetic field was tentatively discussed.     

Growth Kinetics of Single Inclusion Particle in Molten Melts

On the basis of the single-particle framework, a new theory on inclusion growth in metallurgical melts is developed to study the kinetics of inclusion growth on account of reaction and collision. The studies show that the early growth of inclusion depends on reaction growth and Brawnian motion collision, and where the former is decisive, the late growth depends on turbulence collision and Stokes＇ collision, and where the former is dominant; collision growth is very quick during the smelting process, lessened in the refining process, but nearly negligible in the continuous casting process.