Liposomes with precisely controlled composition are usually used as membrane model systems to investigate the fundamental interactions of membrane components under well-defined conditions. Hydration method is the most common method for liposome formation which is found to be influenced by composition of the medium. In this paper, the effects of small alcohol (ethanol) on the hydration of lipid molecules and the formation of liposomes were investigated, as well as its coexistence with sodium chloride. It was found that ethanol showed the opposite effect to that of sodium chloride on the hydration of lipid molecules and the formation of liposomes. The presence of ethanol promoted the formation of liposomes within a certain range of ethanol content, but that of sodium chloride suppressed the liposome formation. By investigating the fluorescence intensity and continuity of the swelled membranes as a function of contents of ethanol and sodium chloride, it was found that sodium chloride and ethanol showed the additive effect on the hydration of lipid molecules when they coexisted in the medium. The results may provide some reference for the efficient preparation of liposomes.
目的 应用联合微创介入方法治疗中晚期肝癌并探讨其疗效。方法 我院自1998年4月至2008年11月期间采用联合介入治疗的方法，即行经皮股动脉插管肝动脉化疗栓塞术，同期行B超引导下经皮穿刺瘤内乙醇注射(PEI)治疗中晚期肝癌175例。结果 左肝动脉行肝动脉化疗栓塞7例，右肝动脉行125例，单行化疗而未栓塞43例； 175例均行B超引导下PEI。随访6～28个月，平均19.3个月，死亡15例，其中8例死于肝功能衰竭，7例死于上消化道大出血伴肝癌广泛转移。29例存活6～12个月； 146例存活13～28个月，其中27例存活已超过26个月。结论 对于不能切除的中晚期肝癌采用联合介入治疗，因其具有操作简单、疗效可靠、经济、安全等优点，值得临床推广应用。
【摘要】 目的 观察在不同剂量乙醇作用下大鼠下丘脑和脊髓神经细胞P物质的表达情况和扫描电子显微镜（SEM）下神经细胞的形态学变化，探讨乙醇作用下大鼠行为学改变的相关机制。 方法 通过福尔马林实验观察大鼠在不同剂量乙醇及时间作用下行为学的改变；采用免疫组织化学技术检测不同剂量乙醇作用下大鼠脊髓和下丘脑神经细胞中P物质的表达，通过扫描电子显微镜观察神经细胞的形态学变化。 结果 乙醇灌胃后0～2 h大鼠舔足次数有不同程度的变化，组间比较差异有统计学意义（Plt;0.05），灌胃2 h大鼠下丘脑和脊髓P物质表达程度与乙醇剂量有相关关系，扫描电子显微镜下各组大鼠的神经细胞形态学变化显著。 结论 急性乙醇中毒可引起大鼠对疼痛反应的变化，其程度与乙醇剂量和作用时间有关，大鼠下丘脑和脊髓神经细胞中P物质的表达强度与乙醇剂量和作用时间有关。【Abstract】 Objective To observe the expression of substance P(SP)in the hypothalamus and spinal cord nerve cells of rats with different concentrations of ethanol, and to observe the morphological changes of nerve cells by scanning electron microscopic(SEM) for elucidating the mechanism of ethological changes effected with ethanol. Methods Ethological changes were detected through the formalin test; SP expressions in the hypothalamus and the spinal cord were evaluated with immunohistochemistry technology, and the morphological changes of nerve cells were observed by SEM. Results The frequency of licking foot changed when the rats were gavaged with different concentrations of ethanol among zero to two hours, the difference between two groups was statistical signifcant (Plt;0.05). The expression level of SP and the morphological changes of nerve cells in hypothalamus and spinal cord had relationship with the ethanol concentration. Conclusions Acute alcoholism could cause pain dysfunction in rats. The frequency of licking foot of rats is correlated to the role of the time closely. The expression intensity of SP in the hypothalamus and the spinal cord nerve cells are correlated to the concentration of ethanol closely.
The aim of this paper is to explore the prevention of rabbit postoperative abdominal cavity adhesion with poly (lactic-co-glycotic acid) (PLGA) membrane and the mechanism of this prevention function. Sixty-six Japanese white rabbits were randomly divided into normal control group, model control group and PLGA membrane group. The rabbits were treated with multifactor methods to establish the postoperative abdominal cavity adhesion models except for those in the normal control group. PLGA membrane was used to cover the wounds of rabbits in the PLGA membrane group and nothing covered the wounds of rabbits in the model control group. The hematologic parameters, liver and kidney functions and fibrinogen contents were detected at different time. The rabbit were sacrificed 1, 2, 4, 6, 12 weeks after the operations, respectively. The adhesions were graded blindly, and Masson staining and immunohistochemistry methods were used to observe the proliferation of collagen fiber and the expression of transforming growth factorβ1 (TGF-β1) on the cecal tissues, respectively. The grade of abdominal cavity adhesion showed that the PLGA membrane-treated group was significant lower than that in the model control group, and it has no influence on liver and kidney function and hematologic parameters. But the fibrinogen content and the number of white blood cell in the PLGA membrane group were significant lower than those of model control group1 week and 2 weeks after operation, respectively. The density of collagen fiber and optical density of TGF-β1 in the PLGA membrane group were significant lower than those of model control group. The results demonstrated that PLGA membrane could be effective in preventing the abdominal adhesions in rabbits, and it was mostly involved in the reducing of fibrinogen exudation, and inhibited the proliferation of collagen fiber and over-expression of TGF-β1.
ObjectiveTo evaluate the feasibility of the chitosan-poly (lactide-co-glycolide) (PLGA) double-walled microspheres for sustained release of bioactive nerve growth factor (NGF) in vitro.MethodsNGF loaded chitosan-PLGA double-walled microspheres were prepared by emulsion-ionic method with sodium tripolyphosphate (TPP) as an ionic cross-linker. The double-walled microspheres were cross-linked by different concentrations of TPP [1%, 3%, 10% (W/V)]. NGF loaded PLGA microspheres were also prepared. The outer and inner structures of double-walled microspheres were observed by light microscopy, scanning electron microscopy, confocal laser scanning microscopy, respectively. The size and distribution of microspheres and fourier transform infra red spectroscopy (FT-IR) were analyzed. PLGA microspheres with NGF or chitosan-PLGA double-walled microspheres cross-linked by 1%, 3%, and 10%TPP concentration (set as groups A, B, C, and D respectively) were used to determine the degradation ratio of microspheres in vitro and the sustained release ratio of NGF in microspheres at different time points. The bioactivity of NGF (expressed as the percentage of PC12 cells with positive axonal elongation reaction) in the sustained release solution of chitosan-PLGA double-walled microspheres without NGF (set as group A1) was compared in groups B, C, and D.ResultsThe chitosan-PLGA double-walled microspheres showed relative rough and spherical surfaces without aggregation. Confocal laser scanning microscopy showed PLGA microspheres were evenly uniformly distributed in the chitosan-PLGA double-walled microspheres. The particle size of microspheres ranged from 18.5 to 42.7 μm. The results of FT-IR analysis showed ionic interaction between amino groups and phosphoric groups of chitosan in double-walled microspheres and TPP. In vitro degradation ratio analysis showed that the degradation ratio of double-walled microspheres in groups B, C, and D appeared faster in contrast to that in group A. In addition, the degradation ratio of double-walled microsphere in groups B, C, and D decreased when the TPP concentration increased. There were significant differences in the degradation ratio of each group (P<0.05). In vitro sustained release ratio of NGF showed that when compared with PLGA microspheres in group A, double-walled microspheres in groups B, C, and D released NGF at a relatively slow rate, and the sustained release ratio decreased with the increase of TPP concentration. Except for 84 days, there was significant difference in the sustained release ratio of NGF between groups B, C, and D (P<0.05). The bioactivity of NGF results showed that the percentage of PC12 cells with positive axonal elongation reaction in groups B, C, and D was significantly higher than that in group A1 (P<0.05). At 7 and 28 days of culture, there was no significant difference between groups B, C, and D (P>0.05); at 56 and 84 days of culture, the percentage of PC12 cells with positive axonal elongation reaction in groups C and D was significantly higher than that in group B (P<0.05), and there was no significant difference between groups C and D (P>0.05).ConclusionNGF loaded chitosan-PLGA double-walled microspheres have a potential clinical application in peripheral nerve regeneration after injury.
This study aims to compare two kinds of modified poly (lactic acid) (PLA) materials:PLA-chitosan (PLA-CTS) and PLA-poly (glycolic acid) (PLA-PGA). PLA-CTS and PLA-PGA scaffolds were prepared and observed under electron microscope. The scaffold porosity was calculated and the pH of the degradation solution was measured. Then rat olfactory ensheathing cells (OECs) were cultivated, and mixed cultured respectively with two scaffolds as two groups. The proliferation, adhesion rate and growth condition of the OECs were observed and compared between the two groups. Results showed that both the prepared PLA-CTS and PLA-PGA scaffolds were three-dimensional porous structure and the porosity of PLA-CTS was 91%, while that of PLA-PGA was 87%. The pH of degradation solution decreased gradually, of which PLA-PGA fell faster than PLA-CTS. After added to the two scaffolds, most OECs could grow well, and there were no significant differences between the two groups on MTT test and nuclei number determined by fluorescent microscope. However, the cell adhesion rate of PLA-CTS group was significantly higher than that of PLA-PGA. It can be concluded that compared with PLA-PGA, PLA-CTS might be a better choice as OECs scaffold.
Objective To study the efficiency of percutaneous acetic acid injection (PAI) or percutaneous ethanol injection (PEI) in the treatment of primary hepatic carcinoma (PHC). Methods Seventeen and 24 patients with PHC were treated, respectively by PAI or by PEI in our hospital. According to hepatic function test, soluble intereukin-2 receptor (sIL-2R), AFP, biopsy and size of tumor, the evaluation was made.Results Effective rate was 88.2% in PAI group and 87.5% in PEI group, respectively. There was no obvious influence to sIL-2R in serum in the two groups (Ｐ＞0.05). Obvious differences in impairment of hepatic functions between PAI and PEI groups were found (Ｐ＜0.01), it also showed that smaller amounts of acetic acid and less puncture frequency were required for the treatment than that of ethanol. Conclusion PAI is superior to PEI in the treatment of those patients who are complicated with cirrhosis or other vital disease.
ObjectiveTo evaluate the two means of field molluscicidal effect by two different snail control drugs--new plant snail control agent luo-wei (Tea-seed distilled saponins, TDS) and 50% wettable powder of niclosamide (WPN). MethodsSuch databases as CNKI, WanFang Data, VIP and CBM databases were searched for controlled trials about TDS vs. WPN for the molluscicidal effect from their establishment to April 2014. Two reviewers independently screened literature according to the inclusion and exclusion criteria, extracted data and assessed the methodological quality of included studies, and then meta-analysis was performed by using RevMan 5.2 software. ResultsA total of 9 studies were included. The results of meta-analysis showed that:Snails mortality rate of TDS on 7 d was lower (RR=0.96, 95%CI 0.93 to 1.00, P=0.04) than WPN and no significant difference of the snails mortality rate on 1 d or 3 d between the two groups was found by means of immersion. Meanwhile, by means of spraying, there were no significant differences on the snails mortality rate on 1 d, 3 d, 7 d, 15 d between the two groups; densities of living snails on 15 d wasn't, either. Based on GRADE system, the evidence was at level B or C. ConclusionCompared with WPN, TDS has reached the requirements of the natural source twin-screw agent field evaluation. The molluscicidal effect of TDS is better, with its large stock and low price, it is worthy to do further popularization.
Objective To observe the degradation of the polyactic glycolate acid (PLGA) microparticles with releasing-slowly vascular endothelial growth factor(VEGF) synthesized by the method of emulsification-diffusion. Methods The method of emulsification-diffusion is to incorporate VEGF into microparticles composed of biodegradable PLGA. The controlled release of microparticles are acquired. The content of the VEGF released slowly from PLGA microparticles in vitro was detected with ELISA at different time. Results We synthesized 100 releasing-slowly VEGF PLGA microparticles with the size of 0.20-0.33 μm by 5 times. The contents were 62±11 ng/L, 89±14 ng/L, and 127±19 ng/L in the 1st, the 2nd and the 3rd months after degradation, respectively. Conclusion The PLGAmicroparticles with releasing-slowly VEGF can be synthesized by the method of emulsification-diffusion.