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.

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.

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.

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.

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.

Magnetic induction hyperthermia becomes a very important tumor treatment method at present. In order to ensure a successful operation, doctors should make hyperthermia treatment planning before surgery. Based on Integration Healthcare Enterprise (IHE) framework and Digital Imaging and Communications in Medcine (DICOM) standard, we proposed and carried out a network workflow integrated with modern medical information systems for the dissemination of information in magnetic induction hyperthermia like accurate accessing patient information and radiology image data, storing processed images, sharing and verifying hyperthermia reports. The results proved that our system could not only improve the efficiency of magnetic induction hyperthermia treatment planning, but also save medical resources and reduce labor costs.
Humans ; Hyperthermia, Induced ; Image Processing, Computer-Assisted ; Magnetic Phenomena ; Neoplasms ; therapy ; Radiology Information Systems ; Systems Integration

Objective To study the impact of implanted thermoseeds of magnetic induction hyperthermia on radiation dose distribution. Methods To simulate irradiation, an anthropomorphic phantom and three-dimensional treatment planning system were used. The impact of thermoseeds on radiation dose distribution was evaluated. Results The change of absorbed dose caused by the implantated thermoseeds was less than 1.5%. Conclusions The impact of implanted thermoseeds on radiation dose distribution is small and comes up to the requirements that the total target dose uncertainty must be less than 5%. Therefore, the impact of thermoseeds on the absorbed dose in tissue can be ignored in clinical practice.

Objective To investigate the dose-response relationship of the treatment temperatures and heating time on human cervical carcinoma hela cells,aiming at providing experimental evidences for clinical hy-perthermia. Methods Hela cells were heated at 37 ～ 70 ℃ in temperature-controlled water baths, the tempera-ture was divided into nine groups,each time was divided into eight subgroups (1 ～ 30 min). The morphology changes of cells after hyperthermia were detected by inverted microscope. Proliferation rates were measured by MTT colorimetric assay. The apoptesis rates were determined by flow eytometric analyse. The levels of prolifera-ring cell nuclear antigen (PCNA) were measured with immunohistochemistry. Results lnereaseing the heating time at the same temperature, or increaseing heating temperature at the same time, the cell proliferation, survival rates and PCNA expression decreased. There was no significant morphological change about cells ,but have small amount of apoptosis and a direct role of the suppression and destruction at 41 ℃ and 43 ℃ group. A large num-ber of cells shrinked to round and a major role for apoptosis at 46℃ group. Cell necrosis was major role at 50 ℃and 55 ℃ group. More than 55 ℃ for necrotic cells. Conclusion With the increase of heating temperature and heating time, its treatment of Hela cells gradually enhance. So combining dose-effect relationship of hyperthermia temperature and time can reach the best therapeutic effects.