1.Progress in the development of carbon nanotubes as drug delivery carrier combined with thermotherapy in cancer therapy
Zhiting SUN ; Xia DONG ; Xigang LENG
International Journal of Biomedical Engineering 2016;39(6):376-381
Most of the anticancer drugs have some limitations in clinical application,such as poor solubility,low targeting and cytotoxicity to normal tissue and organ.The application of drug carriers offers a solution of these problems to a certain extent.In recent years,some materials such as polymers,liposomes,carbon nanotubes (CNTs) were used as carriers of anticancer drugs.The utilization of these carriers improved drug targeting and reduced adverse reactions by targeted modification of carriers which ensured the slow release of the drugs and maintained the plasma concentration.In these carriers,CNTs,as a novel nano-material,have attracted more attention in nanomedical applications.CNTs not only possess nanoscaled diameter,hollow structure and large aspect ratio,resulting in large drug capacity,but also can selectively absorb near infrared lights and transform them into thermal energy,according to the research finding.The functionalized drug-loaded CNTs in combination with thermotherapy shows potential,which is expected to become a new targeting therapy of cancer.In this paper,the basic structure of CNTs,the application of CNTs as drug carriers,and the recent development of functionalized CNTs as drug carriers combined with thermotherapy in tumor therapy were summarized.
2. Detection of Peripheral Blood SEPT9 Gene Methylation Combined With Glycoprotein Tumor Markers in Diagnosis of Colorectal Cancer
Chinese Journal of Gastroenterology 2019;24(6):362-365
Background: SEPT9 gene methylation is a specific biomarker of colorectal cancer, and its peripheral blood expression level can assess the risk of colorectal cancer. Aims: To investigate the clinical significance of detection of peripheral blood SEPT9 gene methylation and glycoprotein tumor markers in the diagnosis of colorectal cancer. Methods: A total of 57 normal controls, 61 colorectal adenoma and 71 colorectal cancer patients from Dec. 2016 to Apr. 2017 at the First Affiliated Hospital of Soochow University were enrolled. The peripheral blood SEPT9 gene methylation was detected by PCR fluorescence probe method, and levels of tumor markers CEA, CA125, CA19-9, CA72-4 and CA211 were determined. ROC curve was used to analyze the diagnostic value of above-mentioned indices for colorectal cancer. Logistic regression equation was established and used to evaluate the diagnostic value of SEPT9 gene combined with CEA. Results: The positivity rates of SEPT9 gene methylation in normal control group, adenoma group and colorectal cancer group were 0, 6.6% and 52.1%, respectively. CEA level in colorectal cancer group was significantly higher than that in normal control group and adenoma group (P<0.05). ROC curve analysis showed that AUC of SEPT9, CEA, combination of the two indicators for the diagnosis of colorectal cancer were 0.817, 0.707 and 0.793, respectively. Logistic regression analysis showed that the OR of SEPT9 and CEA for the diagnosis of colorectal cancer were 1.394 (1.198-1.762) and 1.325 (0.997-1.622), respectively. Conclusions: The positivity rate of peripheral blood SEPT9 gene methylation is significantly increased with the progress of disease, and the diagnostic value for colorectal cancer is high. The combination of peripheral blood SEPT9 gene methylation and CEA is helpful for improving the early screening rate of colorectal cancer.
3.Preparation and cytotoxicity study of multi-wailed carbon nanotubes modified with low-molecular-weight chitosan
Xia DONG ; Lanxia LIU ; Dunwan ZHU ; Hailing ZHANG ; Xigang LENG
International Journal of Biomedical Engineering 2015;38(1):11-14,后插3
Objective To prepare stable aqueous dispersions of chitosan/multi-walled carbon nanotubes (CS/MWCNTs) composites,and observe the effects of CS/MWCNTs on the growth of human umbilical vein endothelial cells (HUVEC).Methods CS/MWCNTs composites were prepared by electrostatic interactions between negatively charged MWCNTs and positively charged low-molecular-weight CS.The prepared CS/MWCNTs were characterized by transmission electron microscopy and Zetasizer nano-analyser.The cellular uptake of the fluorescently labeled CS/MWCNTs was observed by laser confocal microscopy after incubating with HUVEC for 24 h at different concentrations.In vitro cytotoxicity and cellular reactive oxygen were also detected.Results When the mass ratio of low-molecular-weight CS to MWCNTs was equal or greater than 10∶1,the CS/MWCNTs can be stabilized in solution.Cellular uptake experiments showed that the CS/MWCNTs could enter into the cells and locate mainly in the cytoplasm.Cytotoxicity study showed that the CS/MWCNTs composites was less toxic than MWCNTs alone at high concentration (10 and 20 μg/ml).However,there was no significant differencein the level of cellular reactive oxygen between the two groups (P<0.05).Conclusions CS/MWCNTs composites showed low cytotoxicity and high stability,which would be a promising carrier for drug delivery.
4.Role of spinal dopamine D2 receptors in a rat model of neuropathic pain
Xin LENG ; Liqin JUAN ; Zhengliang MA ; Xiaoping XIA
Chinese Journal of Anesthesiology 2015;35(3):330-332
Objective To evaluate the role of spinal dopamine D2 receptors in a rat model of neuropathic pain.Methods Thirty healthy male Sprague-Dawley rats,aged 6-8 weeks,weighing 180-200 g,wcre randomly divided into 5 groups (n =6 each) using a random number table:control group (group C),sham operation group (group S),neuropathic pain group (group NP),normal saline group (group N) and dopamine D2 receptor agonist quinpirole group (group Q).Neuropathic pain was produced by chronic constriction injury of the sciatic nerve (CCI) in rats anesthetized with intraperitoneal 2% pentobarbital sodium 40 mg/kg.At 7 days after CCI,normal saline 10 μl was injected intrathecally over 30 s in group N,and quinpirole 10 μg (in 10 μl of normal saline) was injected intrathecally over 30 s in group Q.At 1 day before CCI,3 and 7 days aher CCI,and 30 min and 1,2,4,8 and 16 h after administration,mechanical paw withdrawal threshold (MWT) and thermal paw withdrawal latency (TWL) were measured.Results There was no significant difference in MWT and TWL at each time point between group C and group S.MWT was significantly lower,and TWL was shorter at T1-8 in NP,N and Q groups than in C and S groups.Compared with group N,no significant change was found in MWT and TWL at each time point in N group,and MWT was significantly increased,and TWL was prolonged at T4-6 in group Q.Conclusion Inhibited function of spinal dopamine D2 receptors is involved in the maintenance of neuropathic pain in rats.
5.Comparative Study on Concentration Monitoring of CsA in Human Whole Blood by EMIT and HPLC
Xia XU ; Songgang JI ; Xiangyu HOU ; Ping LENG ; Chunyan WANG
China Pharmacist 2014;(12):2003-2006
Objective:To compare the difference and correlation of HPLC and enzyme-multiplied immunoassay test( EMIT) for the determination of CsA in human whole blood. Methods:A total of 119 clinical samples at different concentrations of CsA were collected and respectively determined by HPLC and EMIT. The difference and correlation of the two determination methods were investigated. Results:There was significant difference in the blood concentrations of CsA determined by HPLC and EMIT(P<0. 05). CsA concen-tration determined by EMIT was 26. 2 ng·ml-1 higher than that determined by HPLC, and 95% CI was (14. 6-37. 7) ng·ml-1 . A satisfactory correlation was achieved between the two methods(r=0. 997 4). Conclusion:There is statistically significant difference in the CsA concentration in whole blood respectively determined by EMIT and HPLC. Attention should be paid to CsA monitoring by E-MIT and HPLC, and relevant adjustment should be carried out.
6.Risk factors of delayed gastric emptying after pancreaticoduodenectomy
Qiyu LIU ; Li LI ; Hongtian XIA ; Wenzhi ZHANG ; Shouwang CAI ; Zhiwei LIU ; Jianjun LENG
Chinese Journal of Hepatobiliary Surgery 2014;20(10):719-722
Objective To study the risk factors of delayed gastric emptying (DGE) after pancreaticoduodenectomy (PD).Methods Between Ja(n)uary 1st 2013 and December 31st 2013,data from 196 consecutive patients who underwent PD at the Chinese PLA General Hospital were studied retrospectively.17 factors were examined.Univariate analysis and multivariate logistic regression analysis were used to determine the relative risks.Results DGE occurred in 71 patients (36.2%).The incidences of grade A,grade B and grade C DGE were 22.4% (44/196),6.1% (12/196) and 7.7% (15/196) respectively.There were three postoperative deaths.The overall mortality rate was 1.5%.BMI,Braun anastomosis,clinically relevant postoperative pancreatic fistula (CR-POPF) and intra-abdominal collection were significantly correlated with DGE on univariate analyses.BMI ≥25 kg/m2,CR-POPF,and intra-abdominal collection were independent risk factors on univariate and multivariate regression analyses.Conclusions Post-operative complications were associated with DGE.Early diagnosis and timely treatment for pancreatic fistula and abdominal collection were helpful to decrease morbidity and to promote recovery of DGE.
7.Study on the cytotoxicity and gene transfection of NMPCS/DNA nanoparticles
Liping SONG ; Dunwan ZHU ; Lanxia LIU ; Xia DONG ; Hai WANG ; Jingen BAI ; Xigang LENG
International Journal of Biomedical Engineering 2012;35(3):165-168,后插7
ObjectiveTo investigate the cytotoxicity and gene transfection mediated by NMPCS/DNA nanoparticles.MethodsN-methylene phosphonic chitosan (NMPCS) was synthesized using one-step reaction under homogeneous conditions.The NMPCS/DNA nanoparticles were prepared using complex coacervation method.The cytotoxicity of NMPCS alone and its complexes with plasmid DNA were determined by MTT assay on HeLa cells.The gene transfection mediated by NMPCS/DNA nanoparticles were investigated using pGL3control vector as reporter gene.ResultsThe MTT results suggested that the NMPCS and NMPCS/DNA complexes showed significantly lower cytotoxicity than PEI and PEI/DNA complexes,respectively.The gene transfection mediated by NMPCS/DNA nanoparticles were greatly improved compared with unmodified chitosan.ConclusionNMPCS would demonstrate great potential as a novel,safe,efficient non-viral vector for gene delivery.
8.Effects of chitosan/modified chitosan DNA nanoparticles on the differentiation of human naive CD4+ T cells
Lanxia LIU ; Dunwan ZHU ; Xia DONG ; Liping SONG ; Hailing ZHANG ; Xigang LENG
International Journal of Biomedical Engineering 2011;34(2):91-93
Objective To investigate the impact of chitosan and alkylated chitosan DNA nanoparticles on the function of human naive CD4+T cells.Methods The secretion of cytokines (IL-4 and TNF-γ) was observed after the co-incubation of human naive CD4+T cells with nanoparticles 12 h,24 h and 48 h,respectively.ResultsNone of the nanoparticles induced the production of cytokines ( IL-4 and TNF-γ ).Conclusion Chitosan and alkylated chitosan DNA nanoparticles will not induce the differentiation of human naive CD4+ T cells into T1 or T2 and may be considered as a safe gene carrier.
9.High-copy expression of tissue factor pathway inhibitor in pichia pastoris
Xu CHENG ; Weijie XU ; Liping SONG ; Lanxia LIU ; Xia DONG ; Hailing ZHANG ; Dunwan ZHV ; Xigang LENG
International Journal of Biomedical Engineering 2011;34(3):135-139
Objective To generate recombinant Pichia pastoris for high-copy expression of human tissue factor pathway inhibitor (TFPI). Methods The cDNA encoding human TFPI was inserted into the expression vector pPIC9K and the constructed expression vector rhTFPI-pPIC9K was confirmed by restriction endonuclease analysis and DNA sequencing. The recombinant plasmids were subsequently transformed into Pichia pastoris GS115 cells, and the transformants were confirmed by PCR amplification of the genomic DNA.The recombinant Pichia pastoris with high copies of TFPI cDNA was screened by G418 selection. Western blot and TFPI ELISA Kit were employed to analyzing. The temperature, time and concentration of methanol for the induction of recombinant protein were optimized. Results PCR analysis and DNA sequencing confirmed the successful construction of the expression vector rhTFPI-pPIC9K. Real time quantitative PCR and Western blot analysis demonstrated the positive correlation between TFPI expression level and the copy number of TFPI cDNA in Pichia pastoris cells. Optimization of the induction condition significantly elevated the expression level and activity of TFPI (9.95±0.78 mg/L and 3.91±1.37 U/mL). Conclusion The Pichia pastoris strain with high copy of TFPI expression was successfully constructed, which lays a solid foundation for the further investigation on the function of TFPI and its application in the prevention and therapy of diseases.
10.Critical Scoring Systems in the Treatment of Multiple Organ Dysfunction Due To Organic Fluorine Gas Poisoning
Tao GUO ; Jun CAO ; Gang WANG ; Yanxue WANG ; Fengying LENG ; Zhijie XIA
Journal of Kunming Medical University 2016;37(11):101-104
Objective To investigate the value of critical scoring system in the treatment of multiple organ dysfunction after exposure to poisoning by analyzing 3 cases of industrial organic fluorine gas poisoning.Methods Clinical data of symptoms,signs,treatments,outcome and the changes in the scores as APACHE Ⅱ,SOFA,MODS were collected,the differences among the patients were compared and the relevance was analyzed.Results The first APACHE Ⅱ was 19-26.Scores of case 1 in the three scoring systems constantly increased and different components were found,with the suggestion of sequential organ dysfunction.Other two patients' scores decreased and survived without complications.Conclusiorn Multiple critical scoring systems can be used to evaluate the outcome of multiple organ dysfunction due to organic fluorine gas poisoning.System evaluation and individualized treatment are both important.More studies can help to set up a special critical scoring system.