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.

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.

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.

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.

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.

ObjectiveTo isolate and identify endothelial progenitor cells (EPCs) from human umbilical cord,and to study the cell proliferation and gene transfection of green fluorescent protein plasmid in vitro.MethodsEPCs were isolated from human umbilical cord in enzyme digestion method.The biological characteristics of EPCs were identified by flow cytometry and laser confocal microscope.The enhanced green fluorescent protein (EGFP) gene transfection mediated by EPCs was investigated using Lipofectamine 2000 as transfection reagent.ResultsEndothelial progenitor cells isolated from umbilical cord formed typical endothelial cell colony 9 days later.These cellsdisplayed an improved positive expression of CD133 and kinase insert domain receptor (KDR).The endotheliallineage characteristics of expanded cells were confirmed by fluorescein isothiocyanate (FITC)-UEA-1 binding and DiI-ac-LDL uptake assay with the aid of laser confocal microscope.The transfection results demonstrated high expression of EGFP taking EPCs as host cell.ConclusionEndothelial progenitor cells isolated from umbilical cord can be propagated and induced to differentiate into endothelial cells in the appropriate culture conditions.EPCs demonstrated to be an ideal carrier for gene and cell therapy.

ObjectiveConjugation of fluorescent dye onto plasmid DNA was investigated in order to monitor delivery process of plasmid DNA.MethodsPlasmid was activated with bromine,stored for different timeintervals at 4 ℃ or room temperature,and subsequently coupled with 1,10-diaminodecane to prepare aminemodified plasmid DNA.Amine-modified plasmid was then reacted with isothiocyanate (FITC) for fluorescent labeling,and the labeling ratio was calculated after purification.The effect of storage conditions (time/temperature) of bromine-actived plasmid (BP) on fluorescent labeling efficacy was estimated,and the cell transfection efficiency of fluorescent plasmid-lipofectamine complex was observed.The fluorescent plasmid delivered by lipofectamine 2000 in A10 cells was observed by laser scanning confocal microscope (LSCM) and flow cytometry.ResultsThe experimental data showed that prolonged storage time of bromine-activated DNA had a negative effect on the labeling ratio,and lower storage temperature had a positive effect on the labeling ratio.It also demonstrated that FITC modification had no effect on the transfection efficiency of plasmid-lipofectamine complex as compared with that of unlabeled plasmid-lipofectamine complex,and FITC modified plasmid had enough fluorescent intensity to monitor cell uptake with flow cytometer and sub-cellular distribution with LSCM.ConclusionA facile method for conjugating fluorescent dye onto plasmid was established in the study,and could be utilized to trace the plasmid delivery for investigating the transfection mechanism.

Objective To detect the size distribution and Zeta potential of LHRH-MPG△NLS/CDK-siRNA nanoparticles,to observe the effect of different solvents on the nanoparticle size,and to investigate the inhibitory effect of nanoparticles on HepG2 cell growth.Methods LHRH-MPG △NLS and CDK2-siRNA were mixed by continuous stirring to form nanoparticles at different N/P ratios (10/1,20/1 and 40/1).The size distribution and Zeta potential of LHRH-MPG△NLS/CDK2-siRNA nanoparticles were detected by dynamic light scattering,and the stability of the nanoparticles in normal saline,10％ glucose and pure water was discussed.Finally,the inhibitory effect of the nanoparticles on HepG2 cells was determined by CCK8 kit.Results The mean size of the nanoparticles was within 200 nm,and the Zeta potentials were (70±5) mV (N/P=10/1),(120±5) mV (N/P=20/1) and (130±5) mV (N/P=40/1),respectively.The size of the nanoparticles in normal saline was significantly increased,which demonstrated that strong electrolytes had a great impact on the nanoparticles size.When nanoparticle concentration was 200 nmol/L,LHRH-MPG△NLS/CDK2-siRNA nanoparticles (N/P=10/1) showed significantly inhibitory effect on HepG2 cell growth.Conclusions The mean size of the LHRH-MPG△NLS/CDK2-siRNA nanoparticles was within 200 nm,which was ideal for cellular uptake.The Zeta potential of nanoparticles revealed that nanoparticles could be stable in aqueous solution,while strong electrolytes would affect nanoparticle size.When nanoparticle concentration was 200 nmol/L,LHRH-MPG△NLS/CDK2-siRNA nanoparticles (N/P=10/1) showed significantly inhibitory effect on HepG2 cell growth.

Objective To investigate the effects of penehyclidine hydrochloride on activities of nuclear factor kappa B (NF-kB) and activator protein-1 (AP-1) during actue lung injury induced by blunt chest trauma-hemorrhagic shock and resuscitation (HSR) in rats.Methods Thirty male Sprague-Dawley rats,aged 8 weeks,weighing 250-300 g,were randomly assigned into 3 equal groups (n =10 each) using a random number table:sham operation group (group S),blunt chest trauma-HSR group (group THSR) and penehyclidine hydrochloride group (group PHCD).The model of actue lung injury induced by blunt chest trauma-HSR was induced by dropping a 300 g weight onto a precordium in anesthetized rats.Blood was withdrawn via the femoral artery 5 min later until MAP was decreased to 35-45 mmHg within 15 min and maintained at this level for 60 min,followed by resuscitation.In PHCD group,PHCD 2 mg/kg was injected intravenously at 60 min after hemorrhagic shock.At 6 h after the model was established,blood samples were obtained for measurement of concentrations of tumor necrosis factor-alpha (TNF-α) in serum.The lungs were then removed for determination of lung water content,myeloperoxidase (MPO) activaty (by colorimetric assay),NF-κB and AP-1 activaties (using electrophoretic mobility shift assay) in lung tissues,and for microscopic examination of pathologic changes (under light microscope).The left lung was lavaged,and lung permeability index (LPI) was calculated.Results Compared with S group,lung water content,LPI,serum TNF-α level and activites of MPO,NF-κB and AP-1 were significantly increased in THSR and PHCD groups.Compared with THSR group,lung water content,LPI,serum TNF-α concentrations and activites of MPO,NF-κB and AP-1 were significantly decreased in PHCD group.The pathological damage to lung tissues was significantly reduced in PHCD group as compared with THSR group.Conclusion PHCD can inhibit activities of NF-κB and AP-1 in lung tissues,thus mitigating acute lung injury induced by blunt chest trauma-HSR in rats.

Objective To investigate the effects of penehyclidine hydrochloride on Fas/FasL expression during acute lung injury induced by blunt chest trauma-hemorrhagic shock and resuscitation (HSR) in rats.Methods Thirty male SPF Sprague-Dawley rats, aged 8 weeks, weighing 245-275 g, were randomly assigned into 3 equal groups using a random number table: sham operation group (group Sham) , blunt chest trauma-HSR group (group THSR) and penehyclidine hydrochloric group (group PHCD).The model of acute lung injury induced by blunt chest trauma-HSR was induced by dropping a 300 g weight onto a precordium in anesthetized rats.Blood was withdrawn via the femoral artery 5 min later until mean arterial pressure was decreased to 35-45 mmHg within 15 min, and maintained at this level for 60 min, followed by resuscitation.In PHCD group, PHCD 2 mg/kg was injected intravenously at 60 min after hemorrhagic shock.At 6 h after the model was established, the rats were sacrificed, the lungs were then removed for microscopic examination of pathologic changes and for determination of Fas, FasL and caspase-8 expression, and interleukin-6 (IL-6) and IL-1β contents in lung tissues.Apoptotic index was calculated.Results Compared with group Sham, the expression of Fas, FasL and caspase-8 was significantly up-regulated, and AI and contents of IL-6 and IL-1β were increased in THSR and PHCD groups (P＜O.05).Compared with group THSR, the expression of Fas, FasL and caspase-8 was significantly down-regulated,and AI and contents of IL-6 and IL-1β were decreased in group PHCD (P＜0.05).The pathologic changes of lungs were significantly reduced in group PHCD compared with group THSR.Conclusion The mechanism by which penehyclidine hydrochloride inhibits lung cell apoptosis induced by blunt chest trauma-HSR is associated with inhibition of Fas/FasL expression in rats.