中药单体联合CIK细胞治疗恶性肿瘤的研究进展

中药在肿瘤的综合治疗中可通过诱导肿瘤细胞凋亡,促进分化、逆转多药耐药,并能够通过调整机体免疫等途径直接杀伤或间接抑制肿瘤细胞。特别是中药单体既能提高放化疗的敏感性,又能减轻放化疗后的不良反应。而新近临床应用的细胞因子诱导的杀伤细胞具有高效的抗肿瘤作用,在恶性肿瘤的辅助治疗中取得了令人瞩目的成就。两者的联合应用是值得临床探讨的问题。     

冠心Ⅱ号复方及单体组合对大鼠急性心肌梗死的影响

目的:观察冠心Ⅱ号复方及单体组合对急性心肌梗死大鼠心肌酶及TTC染色心梗面积的影响,探讨冠心Ⅱ号可能药效机制。方法:通过结扎冠状动脉左前降支建立心梗大鼠模型,将模型大鼠分为模型对照组、冠心Ⅱ号复方组,冠心Ⅱ号单体组,并设假手术组和空白对照组,给药后采血测定血清CK、CK-MB、LDH水平,并取心脏行TTC染色测定心肌梗死面积。结果:与模型对照组比较,两用药组的心梗面积显著下降(P<0.01或P<0.05),但两组间无差异;心肌酶CK、CK-MB表达单体组低于复方组(P<0.05),LDH水平两组相当。结论:冠心Ⅱ号单体组在改善心梗面积方面与复方组相当的同时,表现出了优于复方组的降低心肌酶的趋势。因而进一步验证了吸收入体内的原形成分才有可能是药效成分的假说。     

PVC/PE液体复合硬片中HDI单体残留量考察

目的:检测样品中使用的粘合剂中HDI单体残留量。方法:样品提取后,与1,2-吡啶哌嗪溶液衍生化后采用反相高效液相色谱法测定。色谱柱:Waers Xterra(C184.6×250 mm5μm;流动相:乙腈-水-冰醋酸(58∶42∶0.15)用三乙胺调节pH至4.0;流速:0.9 ml.min-1;柱温:35℃;检测波长:310nm。结果:线性范围0~0.8208μg.ml-1(r=0.9998,n=7);精密度:0.4%;阴性回收率平均值:99.88%。结论:本方法专属性强、灵敏度高、准确、可靠、简便,可用于HDI残留量检测。     

Miniemulsion Polymerizations Using Static Mixers: Towards High Biocompatible Hydrophobe Contents

Simple static mixers have been used as homogenization devices to perform polymerizable miniemulsion dispersions with negligible heat generation from mixtures containing vinyl acetate as the monomer and high amounts of biocompatible viscous oils (Miglyol and vitamin E acetate) as the hydrophobic components. A triblock non‐ionic copolymer was used as surfactant. The size of the initial droplets was in the 100–300 nm range, increasing with the amount of the hydrophobe oil. These droplets have successfully been polymerized by using lauroyl peroxide or H₂O₂/ascorbic acid as initiators in order to get non‐charged primary radicals. Stable nanoparticles with sizes around 300 nm have been obtained that display colloidal stabilization at 4 and 25 °C upon a long storage time.

     

Mechanical properties and thermal behaviour of PEGDMA hydrogels for potential bone regeneration application

Poly(ethylene glycol) hydrogels are currently under investigation as possible scaffold materials for bone regeneration. The main purpose of this research was to analyse the mechanical properties and thermal behaviour of novel photopolymerised poly(ethylene glycol) dimethacrylate (PEGDMA) based hydrogels. The effect of varying macromolecular monomer concentration, molecular weight and water content on the properties of the resultant hydrogel was apparent. For example, rheological findings showed that storage modulus (G′) of the hydrogels could be tailored to a range between approximately 14,000 and 70,000 Pa by manipulating both of the aforementioned criteria. Equally striking variations in mechanical performance were observed using uniaxial tensile testing where reduction in PEGDMA content in the hydrogels resulted in decrease in both tensile strength and Young’s modulus values. Conversely, increases in the elongation at break values were observed as would be expected. Differential scanning calorimetry and dynamic mechanical thermal analysis showed that there was an increase in Tg with an increase in the molecular weight of PEGDMA. The relationship between the initial feed ratio, molecular weight of the macromolecular monomer and the subsequent mechanical properties of the hydrogels are further elucidated throughout this study.     

Influence of oxygen inhibition on the surface free-energy and dentin bond strength of self-etch adhesives

We compared the surface free-energies and dentin bond strengths of single-step self-etch adhesives with and without an oxygen-inhibited layer. The labial dentin surfaces of bovine mandibular incisors were wet ground with #600-grit silicon carbide paper. The adhesives were applied to the ground dentin, light-irradiated, and the oxygen-inhibited layer was either retained or removed with ethanol. The surface free-energies were determined by measuring the contact angles of three test liquids placed on the cured adhesives. The dentin bond strengths of specimens with and without the oxygen-inhibited layer were measured. For all surfaces, the value of the estimated surface tension component was relatively constant at 35.5-39.8 mJ m(-2) . The value of the , Lewis acid component increased slightly when the oxygen-inhibited layer was removed, whereas that of the , Lewis base component decreased significantly. The bond strengths of the self-etch adhesives were significantly lower in specimens without an oxygen-inhibited layer (13.2-13.6 MPa) than in those with an oxygen-inhibited layer (17.5-18.4 MPa). These results indicate that the presence of an oxygen-inhibited layer in single-step self-etch adhesives with advanced photoinitiators promotes higher dentin bond strength.     

Diagnosis and prognosis of overt disseminated intravascular coagulation in a general hospital -- meaning of the ISTH score system, fibrin monomers, and lipoprotein-C-reactive protein complex formation

The meaning, the utility, and the prognostic significance of the International Society of Thrombosis and Hemostasis overt disseminated intravascular coagulation (DIC) score and other parameters of coagulation activation including soluble fibrin monomer complexes (SFMC), antithrombin and protein C consumption, and formation of lipoprotein-C-reactive protein (LP-CRP) complexes (MDA slope 1 and flag A2) were evaluated in 165 inpatients from a general hospital for whom DIC testing was required by the attending physicians.Of these 165 patients, 148 had an underlying disease that clearly justified the laboratory request from our systematic post hoc review of the clinical charts. Of these 148 patients, 28 had a positive overt DIC score, 19 had an A2 flag, and 4 had both. The DIC score was strongly related to several major markers of coagulation activation such as D-dimers, thrombin-antithrombin complexes, and soluble fibrin and was inversely related to antithrombin and protein C levels, which began to fall from DIC score 4 or higher. The formation of LP-CRP complexes was only related to Gram-negative sepsis and these patients had a strong inflammatory reaction. Independent risk factors for death were high creatininemia, positive overt DIC score, and/or presence of SFMC. In patients with positive DIC score, SFMC positivity and low levels of antithrombin and/or protein C were additional risk factors.The ISTH overt DIC score proves useful and adequate as a marker for clinically significant DIC. Illness severity is further defined by SFMC, antithrombin, and protein C levels. LP-CRP complexes are related to sepsis but not to actual overt DIC and lethal prognosis.     

中药单体成分抗白念珠菌实验的研究进展

 近年来随着激素、生物制剂的广泛使用以及HIV、癌症发病率的升高,免疫低下人群逐渐增多,条件致病菌白念珠菌的感染逐年增多,其对抗真菌药物的耐药作用也日渐突出。中药单体成分具有良好的抗真菌作用,毒副作用小,可与抗真菌药物协同作用,降低真菌耐药性,越来越引起重视。本文就中药单体成分小檗碱、黄芩苷、苦参碱等抗白念珠菌的相关实验研究进展作一综述。      

Interference of functional monomers with polymerization efficiency of adhesives

The degree of conversion (DC) of camphorquinone/amine‐based adhesives is affected by acidic functional monomers as a result of inactivation of the amine co‐initiator through an acid–base reaction. During bonding, functional monomers of self‐etch adhesives chemically interact with hydroxyapatite (HAp). Here, we tested in how far the latter interaction of functional monomers with HAp counteracts the expected reduction in DC of camphorquinone/amine‐based adhesives. The DC of three experimental adhesive formulations, containing either of the two functional monomers [10‐methacryloyloxydecyl dihydrogen phosphate (10‐MDP) or 4‐methacryloxyethyl trimellitic acid anhydride (4‐META)] or no functional monomer (no‐FM; control), was measured with and without HAp powder added to the adhesive formulations. Both the variables ‘functional monomer’ and ‘HAp’ were found to be significant, with the functional monomer reducing the DC and HAp counteracting this effect. It is concluded that the functional monomers 10‐MDP and 4‐META interfere with the polymerization efficiency of adhesives. This interference is less prominent in the presence of HAp, which would clinically correspond to when these two functional monomers of the adhesive simultaneously interact with HAp in tooth tissue.     

Influence of intermediate resin on the bond strength of light-curing composite resin to polymer substrate

Objectives. The aim of this study was to examine the effect of intermediate resin (IMR) of different monomer compositions and viscosities on the shear bond strength between polymer substrate and light-curing composite. Methods. The substrate used in the study was an autopolymerizing polymethyl methacrylate (PMMA) based polymer. The substrate was treated with the IMR for 3 min before application of light polymerizable particulate filler composite resin. The monomers of the IMR were either bisphenol-A-glycidyl dimethacrylate (BisGMA) and triethyleneglycol dimethacrylate (TEGDMA) or BisGMA and methyl methacrylate (MMA). The shear bond strength of the IMR treated substrate to the particulate filler composite was evaluated after storing the specimens dry and after thermocycling the specimens in water. Light microscope examination was accomplished to determine the swelled layer of the substrate. Results. Significant differences were found between the shear bond strength values of the IMRs (p < 0.001). The bond strengths were generally higher in the BisGMA-MMA groups than in the BisGMA-TEGDMA groups. Two-way ANOVA revealed significant effects of type of IMR (p < 0.001) and thermocycling (p = 0.017) on the shear bond strength. No interaction was found between these variables (p > 0.05). Conclusions. The results suggest that the monomer composition and ratio of the IMRs used in the study influence the shear bond strength of the polymer substrate to the new resin.