In order to assess whether gene transfection could be mediated by ultrasound in association with P85 and find the appropriate parameters of ultrasound irradiation, the effects of ultrasound with or without P85 on gene transfection of HepG2 cells were examined. The HepG2 cells were irradiated by ultrasound at 1 MHz, 0.4-2.0 W/cm(2) and 50% duty cycle with plasmid encoding enhanced green fluorescent protein (EGFP) as a report gene. Forty-eight h later, the expression of EGFP was detected under the fluorescence microscopy. Transfection efficacy was quantitatively assessed by flow cytometry, and cell viability was evaluated by trypan blue exclusion. The results showed that the transfection efficacy was increased with the increases in ultrasound output power and the ideal transfection efficacy was achieved in HepG2 cells irradiated by ultrasound at 0.8 W/cm(2) for 30 s. The transfection efficacy in ulstrasound+P85 group was three times higher than in single ultrasound group [(17.63+/-1.07)% vs (5.57+/-0.56)%, P<0.05]. The cell viability was about 81% and 62% in ultrasound group and ultrasound+P85 group respectively. It was concluded that ultrasound in combination with P85 could mediate the gene transfection of HepG2 cells, ideal transfection efficacy was achieved by ultrasound irradiation at 0.8 W/cm(2) for 30 s, and P85 could somewhat increase the damage to cells caused by ultrasound.
Cell Survival/genetics ; Green Fluorescent Proteins/genetics ; Hep G2 Cells ; Poloxalene/*pharmacology ; Transfection ; Ultrasonics

Implant-associated infection is a serious problem in the clinical application of biomaterials.which greatly restricts the generalizatjon of cardiovascular biomaterials,while bacterial adhesion is the initial cause for implant-associated infections of cardiovascular biomaterials.Therefore.the prevention of bacteriaI adhesion to the biomaterials plays a crucial role in the cure of biomaterial center infection.It has reported that human plasma protein influences the bacterial adhesion to biomateriais.Some plasma proteins inhibit bacterial adhesion.whereas some promote jt.Study on the correlation between plasma protein and hacterial adhesion to the biomaterials is of great importance in the prevention and cure of biomaterials center infection.

This study examined the effect of P85 (a pluronic block copolymer) and microbubble (MB) ultrasound contrast agents under ultrasound irradiation on gene transfection and expression. The pEGFP plasmids that can encode enhanced green fluorescent protein (pEGFP) served as a report gene and were mixed with different concentrations of MB/0.05% (w/v) P85. Then the plasmids were transfected into human hepatoma G2 (HepG2) cells. The HepG2 cells treated with MB/P85 or without treatment were exposed to ultrasound (US parameters: 1 MHz, 1.0 W/cm(2), 20 s, 20% duty cycle). Twenty-four hours later, the transfection efficiency was assessed by fluorescence microscopy and fluorescence activated cell sorting (FACS) analysis. The cell viability was evaluated by Trypan blue exclusion test. The results showed that the gene transfection efficiency in HepG2 cells under ultrasound irradiation was significantly higher than that without ultrasound irradiation. HepG2 cells in the MB or P85 group in the absence of ultrasound expressed less amount of green fluorescent protein. The expression efficiency reached (22.14±3.06)% and the survival rate was as high as (55.73±3.32)% in the 30% MB plus P85 group. It was concluded that MB and P85 in the presence of ultrasound can enhance gene transfection and expression.

MicroRNAisatypeofsingle-strandednon-codingRNA,directlybondingtothecomplemen-tary target gene mRNA.That leads to the inhibition of mRNA translation of the target molecule in order to reduce expression of the target gene.MicroRNAs are not only involved in the regulation of inflammatory reac-tion,but also play important roles in the formation of neoplasm.The researches showing that the inflammatory reaction interacting with miRNAs results in the differential expressions of microRNAs in lung cancer have been widespreadly concerned.Along with the deepening of the research on the mechanisms of inflammatory reaction and differential expression of microRNAs,it will provide new strategies for the prevention,diagnosis and treat-ment of lung cancer.

Objective To investigate the value of postprocessing technique of multi-slice helical CT for the occult fracture located in complicated structure. Methods One hundred-thirteen patients with acute trauma but negative on plain X-ray film were reviewed retrospectively. All of the patients underwent MSCT ,and original data were reformed with reconstruction. Results Of one hundred-thirteen injuried patients , fractures were demonstrated with MSCT imaging in forty-eight cases. Conclusion The combination use of axial image of MSCT , reconstruction and post-processing is of high value in definite detection of occult fracture , and play an important role in selecting therapy project and evaluating prognosis.

The value of color Doppler flow imaging (CDFI) and intravenous contrast-enhanced ultrasound (CEUS) for assessing the transplanted liver and early diagnosing complications by examining hemodynamic changes was discussed. Seventy-five patients with orthotopic liver transplantation (OLT) underwent CDFI. The following parameters were measured: peak systolic velocity (PS), resistance index (RI) and Doppler perfusion index (DPI) of the hepatic artery (HA), time average velocity (TAV) of portal vein (PV) and velocity of hepatic vein (HV) in different stages postoperation. And 11 patients of them received CEUS. Thirty healthy subjects were enrolled as controls. The results showed that: (1) In 23 patients without obvious complications, TAV of PV within 15 days post-operation was significantly higher than in controls (P<0.05), PS and DPI of HA within 7 days postoperation were lower, but RI was higher than in controls (P<0.05); (2) When the hepatic artery thrombosis (HAT) occurred, PS and DPI of HA were obviously decreased, but TAV of PV significantly increased like a high saw-tooth wave; (3) While rejection occurred, both TAV of PV and PS of HA were decreased with the increase in RI of HA, and the triphasic wave of HV disappeared and displayed as saw-tooth wave; (4) The incidence of biliary complications in liver transplantation was increased when DPI was reduced; (5) Seven cases of hepatic carcinoma relapse after OLT demonstrated hyperecho in the arterial phase and hypoecho in the portal and later phase on CEUS; (6) In 2 cases of HA thrombus, there was no visualized enhancement in arterial phase of CEUS, but enhancement during the portal vein and parenchymal phase. It was concluded that the hemodynamic changes of PV, HA and HV in the transplanted liver are valuable for assessing the transplanted liver and early diagnosing complications on CDFI and CEUS.
Bile Ducts/pathology ; Contrast Media/*administration & dosage ; Hemodynamics ; Hepatic Artery/pathology ; Infusions, Intravenous/*methods ; Liver Transplantation/*adverse effects ; Liver Transplantation/*methods ; Liver Transplantation/ultrasonography ; Perfusion ; Postoperative Complications ; Ultrasonography/*methods ; Ultrasonography, Doppler/*methods

Objective To evaluate the safety and efficacy of multi-band mucosectomy (MBM) for early esophageal cancer and precancerous lesions.Methods Data of 28 patients with early esophageal cancer or precancerous lesions undergoing MBM were reviewed in regarding of procedure complications and follow-up results.Results A total of 32 lesions were resected successfully by MBM in one session,with mean procedure time of 28.3 minutes.The mean diameter of specimens was 12mm.No residual neoplasm was found at the base of any resected specimens.The post-MBM pathological findings consisted of 2 cases of intramucosal cancer,1 case of submucosal cancer,and 25 cases of moderate-severe dysplasia.No perforation,delayed hemorrhage or subcutaneous emphysema occurred.Intraoperative bleeding occurred in 23 cases,including 3 cases of pulsatile bleeding,which were controlled with metal clip,and 20 cases of minor bleeding which were managed with APC or halted automatically at the end of procedure.Chest pain after the procedure occurred in 5 cases and were relieved soon.The patient with submucosal cancer underwent subsequent surgical resection,with no residual cancer in surgical specimen or lymph node metastasis.Twenty seven other cases were followed up endoscopically for 2-12 months.Esophageal stricture occurred in 2 cases,and were successfully relieved by dilatation with stent or bougienage.No recurrent lesion or metastasis were revealed.Conclusion MBM is a relatively safe and effective endoscopic technique for treatment of early esophageal intramucosal cancer and precancerous lesions,but further studies are needed to evaluate the long-term results.

Objective To determine the effect of calcitonin gene-related peptide (CGRP) on triggering receptor expressed on myeloid cells-1 (TREM-1) in the lipopolysaccharide (LPS)-induced macrophages and its signal transduction pathway. Methods The levels of TREM-1 mRNA in the macrophages were observed by reverse transcription-polymerase chain reaction (RT-PCR), and flow cytometry was performed to detect TREM-1 protein expression levels in the macrophages. Results CGRP had no regulating effect on the expression of TREM-1 in the macrophages; LPS could up-regulate macrophages to express TREM-1; CGRP increased TREM-1 mRNA expression in LPS-induced macrophages in dose and time-dependent manner; CGRP increased TREM-1 protein expression in LPS-induced macrophages, which could be partially reversed by H-7 or H-89 (P<0.05). Conclusion CGRP can regulate the LPS-induced macrophages synthesis and secretion of TREM-1, and the intracellular signal transduction pathway is related to PKA and PKC.

BACKGROUND:Studies have demonstrated that prosthetic valve endocarditis is primarily caused by bacteria adhering on the surface of the materials.Thus,the relationship of prosthetic valve materials with bacteria adhesion and growth is an important subject.OBJECTIVE:To explore the influence of prosthetic valve materials on bacteria growth through observing the relationship of bacteria adhesion on prosthetic valve materials and bacteria growth.DESIGN,TIME AND SETTING:Repetitive measurement was performed at the Department of Cardiac and Thoracic Surgery,Third Hospital of Kunming Medical College from January to March 2001.MATERIALS:Terylene(Dacron)was purchased from Man-made Blood Vessel Laboratory of Suzhou Weaves Belt Factory;polytetrafluoroethylene was provided by Teflon-GoreTexW.L.Gore & Associates,Inc.Arizona,USA;pyrolytic carbon was provided by Department of Biological Material of Sichuan Union University;staphylococcus anreus,Escherichia coli,staphylococcus epidermidis,and Pseudomonas aerugmosa were prepared by our laboratory.METHODS:The growth curve of staphylococcus aureus,staphylococcus epidermidis,Escherichia coli and Pseudomonas aeruginosa on dacron,pyrolytic carbon and pelytetrafluoroethylene were quantitatively determined respectively by plate counting and gamma.ray counting of 125 Ⅰ radiolabeled bacteria in vitro.Bacteria growing normally served as control.All bacteria were cultured for 30 hours,and bacteria concentration was determined every 2 hours.In addition,the adhesive capacities of foMr kinds of bacteria on dacron,pyrolytic carbon and polytetrafluoroethylene were detected Escherichia coli and Pseudomonas aeruginosa on dacron,pyrolytic carbon and polytetrafluoroethytene.RESULTS:There were no significant differences in adhesive capacities of each bacterium on dacron,pyrolytic carbon and polytetrafluoroethylene at the same time point(P>0.05).The differences in growth curve of four kinds of bacteria on prosthetic valve materials were not remarkable compared to the control(P>0.05).Different bacteria showed different adhesion degree on the materials:staphylococcus aureus exhibited strongest adhesion on dacron;staphylococcus epidermidis on pyrolytic carbon;Escherichia coli on dacron.The adhesive capacity of Pseudomonas aerugmosa on dacron reached peak within 12 hours,and gradually decreased,but maintained strong adhesion on the other materials.The adhesive capacmes of four bacteria on the materials did not increase or maintain with time.CONCLUSION:The adhesive capacity of one bacterium to different artificial valve materials and different bacteria to one prosthetic valve materials is different.The materials.show little influence on bacterium growth cycle.

Objective To study the effect of histone deacetylase inhibitors on cell cycle of breast cancer cell line MCF-7.Methods The breast cancer cell line MCF-7 was treated by histone deacetylase inhibitors (TSA、SAHA、CS055、MS-275)respectively and observed by MTT assay after 24 hours,48 hours,72 hours,96 hours.The chosen inhibitor was used to treat MCF-7 cell in different concentration.The flow cytometry was used to detect the Sphase cell and Cyclin A2,Cyclin D1.SPSS 10.0 was used to analyze the data.Results Within the four inhibitors,SAHA showed the most powerful effect of depression of cell growth and time-effect relation.The percentage of Sphase cells and level of Cyclin A2 decreased,the level of Cyclin D1 increased.Conclusions SAHA is the most powerful histone deacetylase inhibitors for breast cancer cell MCF-7,the effect of depression of cell growth shows time-effect relation.Cyclin A2 and Cyclin D1 were involed in this regulation of cell cycle.