The vectors play an important role in gene therapy by transporting the therapy genes into target tumor cells. At present there are mainly two kinds of gene vectors, including biological and non-biological vectors. Biological vectors, including virus, bacteria and stem cells, have good target activity and can efficiently delivery the genes into target tumor cells, but have potential genetic hazards.However, non-biological vectors, including liposomes and nanoparticles, can be simplely prepared with high genetic safety, but they can not transport the genes efficiently. Therefore, establishing safe and effective malignant glioma gene treatment system and finding gene vectors with good target activity become the research focus.

Treating tumors with electric field is an interdisciplinary integrated and comprehensive research which applies electro-technology to tumor treatment.This therapy has the characteristics of safe,practical to its users and the parameters are easily to be controlled,which has attracted considerable attention in recent years.The main types of electric field in current research or application are pulsed electric field and direct current electric field.Both of the types can change the environment where tumors grow with different mechanisms,and the tumors would be killed through their pathological changes.Alternating electric field in intermediate frequency is a new type of tumor treating field,which has a promising application prospect.This article reviews the international and domestic research progress of the effects and mechanisms of the three kinds of electric fields used in the treatment of tumors.

Objective To study the laws of heating and thermal field of heating seed arrays in different magnetic field intensity during the magnetic induction hyperthermia.Methods 3.0 cm×3.0 cm ×2.6 cm and 5.0 cm ×5.0 cm×2.6 cm of magnetic heating seed was implanted respectively in 10.0 cm×10.0 cm ×10.0 cm pure agar phantom.The regions was divided into one file per 5 Gs in the range of 60-120 Gs magnetic induction.The temperature measurement experiments were implemented in each sub-file.Muscle-agar mixture model was used in the magnetic induction 60 Gs and 90 Gs to implement GTV-heating simulation experiments and thermal field analysis.Results The pure agar phantom heating experiments show that the heating is of basically the same rule when seeds with various diameters were implanted in the magnetic thermal array.Along with the increase of magnetic induction,the final temperature of the focal point heated for 40 min increased accordingly.and time required for heating to 50℃ was shortened correspondingly.The thermal field analysis of muscle-a mixture agar mixture model showed that the implantation density of magnetic heating seed is closely associated with the temperature of the target area and thermal field in difierent magnetic field intcnsity.Conclusions The magnetic induction has a significant impact on heating of the seeds,as the magnetic modium,and this impact is trending downwards when the magnetic field reaches a certain intensity.Within a certain size,adequate magnetic heating seed density is necessary to achieve the desired temperature required for the temperature value.The heating seeds should be put in a certain order to heat the venue evenly,not in a simply order,but in line with the principle of outer dense and inner sparse.

Objective To study the effects of alternating magnetic field with different intensities on the proliferation of human squa-mous tongue cancer cells in vitro. Methods Viable cells with the OD value cell and flow cytometry were revealed through MTT assay to evaluate the proliferation and apeptosis and cell cycle respectively after the cells were exposed to electromagnetic fields of different intensity (5mT,8mT,11mT) once per day lasting 1 hour for 3 days. The sham -exposure controls were correspondingly established. Results We compared the electromagnetic field groups with the normal groups by MTT assay after 24,48,72 hours. By analyzing the data in SPSS sta-tistical software , we found that the OD value of electromagnetic field groups was significantly less than that of the control groups (P <0.01) . The rates of apoptosis cells by flow cytometry revealed that EMF groups had no change as compared with control groups. But the cell cycle displayed significant chang at 0.5rot. Conclusion The cells displayed significant changes with obvious Tca8113 cell prolifera-tion inhibition and hold - up cell cycle after being exposed to alternating magnetic field of different intensity. But human squamous tongue cancer ceils could not be induced to apeptosis.

Objective To study the preparation method of magnetic fluids and its antitumor effect in combination with paclitaxel thermo-chemotherapy in vitro. Methods Magnetic fluids were prepared by copre-cipitation and modified by sodium oleate. Transmission electron microscopy, Fourier infrared spectroscopy and other instruments were used to characterize the products. The heat effect was studied under ahemating magnetic field in vitro. MTT assay was performed to examine the effect of magnetic fluids in combination with pachtaxel thermo-chemotherapy of human cervical cancer cells Caski. Results The prepared magnetic fluids were global with a diameter of 20～30 nm,Zeta potential was -11 mVto -16 mV. They had distinct heat effect in a alterna-ting magnetic field and could rise to a temperature for tumor thermo-chemotherapy (41 ～ 46℃). Thermo-ehem-otherapy could significantly inhibit the proliferation and promote of the Caski cells, which were more distinct than the magnetic fluids hyperthermia and paclitaxel chemotherapy. Conclusion Magnetic fluids in combina-tion with paclitaxel thermo-chemotherapy has advantages of chemotherapy and hyperthermia. This treatment shows better effects on cell experiments than that of using paclitaxel chemotherapy alone and may provide a new way in clinical treatment for human cervical cancer.

Objective To analyze the dose rate effect and potentially lethal damage repair in DNA double strand break repair deficient murine cells (SCID) irradiated by ? ray. Methods The wild type(CB.17+/+) and SCID cells were exposed to ? ray at high and low dose rates. The high dose rate exposure was fractionated into two equal doses at 24?h intervals. The survival rates of irradiated cells were calculated by clony forming analysis. Results When ? ray was given to wild type(CB.17+/+) cells in two fractions at 24?h intervals, the survival rate was significantly higher than that when the same total dose was given singly. In contrast, there was no difference in the survival rates between the single and fractionated exposure in SCID cells. SCID cells were more sensitive than CB.17+/+ cells to both low and high dose rates ? ray exposure for cell killing. The survival rate by low dose rate exposure was significantly higher than that by high dose rate exposure, not only in CB.17+/+ cells but also in SCID cells. Conclusions SCID cells are deficient in repairing ? ray induced double strand breaks. There is dose rate effect in both SCID and CB.17+/+ cells.

BACKGROUND:Magnetic bone cements have been used to treat bone metastasis in Japan, which are made by adding Fe3O4 nanoparticles to bone cements. Magnetic bone cements containing micron carbonyl iron powder have not been reported.
OBJECTIVE:To prepare polymethylmethacrylate-based cements containing carbonyl iron powder, and to test the magnetic characterizations and the heat-generating abilities of al samples according to ISO 5833 standard in vitro. METHODS:The carbonyl iron powder was mixed with polymethylmethacrylate-based bone cement power to prepare magnetic bone cements containing 0%, 20%, 30%, 40%, and 50%carbonyl iron powder, respectively. The setting time, polymerization temperature, compressive strength, magnetic property and in vitro heat-generating ability were tested.
RESULTS AND CONCLUSION:The setting time and polymerization temperature were increased with the increased content of carbonyl iron powder. The highest polymerization temperature of each sample was 65-70 ℃. The increased content of carbonyl iron power could not change the highest polymerization temperature but delay its appearance. The compressive strength of each sample was higher than 60 MPa, and moreover, the compressive strength of the pure polymethylmethacrylate-based bone cement was higher than 60 MPa, which met the ISO 5833 standard. The saturation magnetic intensity was increased with the increasing of carbonyl iron power content. The heat-generating ability of magnetic bone cements had a positive correlation with the magnetic field strength and the content of carbonyl iron powder.

ObjectiveTo study the effects on growth characteristics of cells mutated by outer space. Methods5 tumor cell lines and 1 bio-pharmaceutical cell line were carried in the recoverable satellite No.18 and returned after 18 days flying in outer space.The cell living systems were utilized in passive carrying. Some survival cells were monocoloned, and the experimental methods such as cell morphological observation,MTT assay and FACS were used for analysis of cell growth characteristics. ResultsThe survival cell rates of tumor cell lines and bio-pharmaceutical cells were markedly different. Compared with the control group, mutated cells appeared to have multiple cell morphological changes and the cell number of G1 phase was increased markedly (P<0.05). Growth rate in mutated cells were varied without specific discipline. ConclusionEffects of outer space on growth characteristics were complicated and multiplex in mutated cells,which were not all heredity in further passage. The differences of the monoclonal cell lines provide the potential to obtain optimizing cell lines by screen.