Objective To evaluate the effect of methylene blue and visible light by FQ-PCR assay on the inactivation of plasma hepatitis B virus,and to establish a direct and impersonal basis for the surveillance of cural inactivation.Methods Four samples of plasma of HBV-DNA positive were added with methylene blue. Then the plasma was processed with visible light radiation(30 000 Lux) for 0, 5, 10, 15,30 min respectively. Moreover,the concentration of HBV-DNA samples was quantitatively detected by the method of FQ-PCR and compared with untreated samples to evaluate the effect of HBV inactivation and its relationship with the time of radiation.Results The original concentration of HBV-DNA was 5.6?107, 3.2?106, 1.8?106,3.5?105 copies/ml respectively. After being added with methyene blue, the concentration of HBV-DNA was significantly decreased(P

A lactoferrin-containing PEGylated liposome system (Lf-PLS) was developed and tested in vitro as a hepatoma-targeting drug delivery system. PEGylated liposomes (PLS) were successfully prepared using the thin film hydration method with peglipid post insertion. Lf was covalently conjugated onto the carboxyl terminal of DSPE-PEG2000-COOH on liposomes. Coumarin-6 was used to trace Lf-PLS with fluorescence. The cellular uptake of this system was carried out in asialoglycoprotein receptor (ASGPR) positive HepG2 cells via confocal microscopy and flow cytometry. The Lf-PLS liposome was observed as spherical or oval vesicles with the particle size around 130 nm, zeta potential about -30 mV and encapsulation efficiency more than 80%. The confocal microscopy images and flow cytometry data demonstrated that Lf-PLS resulted in significantly higher cell association by ASGPR positive HepG2 cells compared to PLS. The association between Lf-PLS and cells were dependent on the concentration, time and temperature, which was inhibited by pre-incubation with excessive free Lf. The results suggest that Lf-PLS has a good targeting effect on HepG2 cells in vitro. The targeting mechanism may be related to the specific binding of Lf and ASGPR on HepG2 cells, which guides Lf-PLS to the cell surface to induce an active endocytosis process. All these results demonstrated that Lf-PLS might be a potential drug delivery system in targeting hepatocellular carcinoma, which deserves more research on its targeting ability, antitumor efficiency, and metabolism in vivo for treatment of hepatomacellular carcinoma.

Objective To study the diagnostic value of heart fat acid binding protein (h‐FABP) in myocardial damage of children with hand‐foot‐mouth disease (HFMD) .Methods From February 2012 to December 2014 ,100 children with HFMD were chosen as study objects .All children study were divided into 2 sub‐groups according to the severity of disease:71 in ordinary HFMD sub‐group ,29 in severe HFMD sub‐group .At the same time ,100 healthy children were chosen as control group .The routine blood test , rate of abnormal electrocardiography ,rate of abnormal cTnI and rate of abnormal h‐FABP were compared among all children .The cTnI and h‐FABP at different time were compared between ordinary HFMD sub‐group and severe HFMD sub‐group .Results The WBC ,RBC and L had significant difference among different groups/sub‐groups(P<0 .05) ,the difference of PLT had no statistical significance(P>0 .05) .In ordinary HFMD sub‐group ,rate of abnormal electrocardiography was 19 .72% (14/71) ,rate of abnormal cTnI was 4 .23% (3/71)and rate of abnormal h‐FABP was16 .39% (10/71);in severe HFMD group ,rate of abnormal electrocardio‐graphy was 72 .41% (21/29) ,rate of abnormal cTnI was 82 .76% (23/29) and rate of abnormal h‐FABP was 82 .96% (23/29);in control group ,rate of abnormal electrocardiography was 1 .00% (1/100) ,rate of abnormal cTnI was 2 .00% (2/100)and rate of ab‐normal h‐FABP was 0 .00% (0/100) ,the difference had statistical significance(P<0 .05) .The cTnI and h‐FABP at different time had significant difference between ordinary HFMD sub‐group and severe HFMD sub‐group(P<0 .05) .Conclusion Heart fat acid binding protein (h‐FABP) can reflect the early myocardial damage in children with hand‐foot‐mouth disease .

Objective To research the structure and principle of Helical Tomotherapy, and study the clinical application value of the equipment system. Methods As the first helical radiotherapy system in the mainland of China, its constructions, structure and principle were analyzed and discussed. Results Helical Tomotherapy is a new kind of radiotherapy equipment. The Hi-Art treatment system is a combination of a LINAC and a CT scanner capable of having the function of both systems. It was approved to achieve the best intensity modulated radiation therapy (IMRT), used for adjusting the setup position of the patient with MVCT and as the basis for dose reconstruction and other adaptive radiotherapy processes. It is the first integrated planning, delivery and verification system for IMRT. Conclusion Image-guided radiation therapy (IGRT) and IMRT have introduced a new era in radiation oncology which will better fight cancer and simultaneously improve the patients' quality of life. Having been designed from the ground up for IGRT and IMRT, the tomotherapy system is in the forefront of technical advancements for efficacy and processes to make it efficiently.

To investigate the patient-specific dose verification method using ArcCHECK for total marrow irradiation (TMI) with Volumetric Modulated Arc Therapy (VMAT) and Helical Tomotherapy (HT). The kVCT images collected from 8 patients were respectively designed for RapidArc and Tomotherapy plans in total marrow irradiation. ArcCHECK was used for dose verification for the head-neck, chest-abdomen and pelvic. The merging function of ArcCHECK was used in VMAT and the method of double plans (reference and delivery plans) were used in HT. The γ-analysis passing rates for the head-neck, chest-abdomen, pelvic were 98.9% ± 1.9%, 98.4% ± 1.8%, 97.4% ± 2.1% for VMAT plans and 94.3% ± 1.5%, 96.5 ± 1.2%, 94.1% ± 1.9% for HT plans. The results show that using the merging function of ArcCHECK can achieve the dose verification well for VMAT plans with TMI. The method of double plans was done for the dose verification of HT plans with TMI as well as the plans with the targets keeping away from the set-up center.
Bone Marrow ; radiation effects ; Humans ; Radiotherapy Dosage ; Radiotherapy Planning, Computer-Assisted ; Radiotherapy, Intensity-Modulated

Objective To evaluate the clinical outcome and the acute toxicity in nasopharyngeal carcinoma (NPC) treated with tomotherapy followed by the anti-EGFR monoclonal antibody.Methods Between March 2008 and November 2009,34 newly diagnosed NPC patients were treated with helical tomotherapy combined with nimotuzumab or cetuximab.All the patients underwent tomotherapy at the dose of 70 Gy/33F for the gross tumor volume (pGTVns) and positive lymphnodes (GTVnd) ,and 60 Gy/33F for the high risk clinical target volume (PTV1),and 56 Gy/33 F for the low risk clinical target volume (PTV2),respectively.17 patients in group N were given weekly injection of 200 mg for 6-7 times and 17 patients in group C were given initial dosage 400 mg/m2 followed by subsequent weekly dosage of 250 mg/m2 for 6-7 times.Acute lesions were evaluated with the RTOG/EORTC criteria.Result The median follow-up time was 22 months.The effective rates (CR + PR) in 3,6 and 12 months were 14/17,12/17,12/17 in group N and 15/17,14/17,14/17 in group C.The 1 year survival rate was 15/17 in group Nand 17/17 in group C.Nimotuzumab had less acute mucositis reaction (u = 2.25,P < 0.05),weight loss(t=2.56,P=0.02) and rash (u=4.36,P＜0.01) compared with cetuximab.Conclusions Helical tomotherapy combined with nimotuzumab or cetuximab was effective and made no difference in the shortterm efficacy and 1 year survival rate for the patients with NPC.Nimotuzumab has less acute reaction than cetuximab.More studies should be done to prove long-term effects.

Objective The aim of this work is to compare the performances of EDR2 film dosimetry with two-dimensional ion chamber array (2DICA) in quality assurance (QA) procedures and to investigate the origin of possible discrepancies between the two methods.Methods A 2DICA, I′mRT MatriXX and MULTICube equivalent solid water phantom from IBA Company were used to verify the dose distribution of 15 tomotherapy plan cases.The combined phantom which includes EDR2 film on the array was set up to measure the dose distribution from coronal and sagittal orientations.After the irradiation, the dose distributions of 2DICA and film were compared with those calculated in the planning system for verification.The results and efficiency were evaluated independently in the two methods.Results The mean number of points satifying γ parameter ≤1 in the coronal and sagittal planes was 97.00%±1.56%& 95.98%±2.52%(t=-2.22,P=0.043) and 98.28%±1.55%& 95.42%±1.99%(t=0.75,P=0.464) of the 15 cases respectively for 2DICA and EDR2 film.The ratio of more than 90% and 95% were 93.3% and 66.7%.The results we presented show a very good agreement between the two methods when used to assess the dose distribution between calculated and measured doses,and a certain degree of correlation (r=0.14,P=0.001).Conclusions The 2DICA may effectively replace both film and ion chamber dosimetry in routine IMRT QA.The good agreement between 2DICA and EDR2 film may give a possible check regularly just as a gold standard.

Objective To evaluate the clinical feasibility of quality assurance of helical tomotherapy intensity modulated radiation therapy (IMRT) through a series of clinical case studies. Methods Tomotherapy planning system was used to provide optimized IMRT treatment plans. To verify the dose of IMRT plans,the cylindrical Virtual Water phantom,0.056cm3 AISL, ion chamber and EDR2 film were used for getting the absolute and relative doses from tomotherapy IMRT planning. The film and ion chamber were placed into the phantom. The doses of the interesting points and isodose distribution of the axial plane were measured,then the results were compared with those from the calculation in planning system for verification. Before the irradiation,kVCT images of the phantom were registered by tomotherapy MVCT images. So the setup of phantom was guided for verifying the position. Results The isedose distribution (on the axial plane) measured by the film was well consistent with that calculated by tomotherapy planning system. The error between the measured dose and predicted dose in the measured points was less than 3%. The setup error of the phantom was able to be kept within 1 mm. There was 2 mm offset along the vertical direction of couch from the virtual isocenter to beam isocenter,which should be considered during the phantom/patient setup. Conclusions The procedures for quality assurance of tomotherapy IMRT are feasible in our experience. And helical tomotherapy IMRT QA system has been constituted.

Objective To investigate the feasibility of dose verification of intensity modulated (IM) planning of helical tomotherapy (HT) using two-dimensional ion chamber array (2DICA),and develop an efficient way to validate the dose delivered under the parameters mirroring those during the treatment. Meth-ods A 2DICA,I'mRT MatriXX and MULTICube equivalent solid water phantom from IBA company were used to verify the dose distribution of 10 IM planning. The combined phantom was set up to measure the dose distributions on coronal and sagittal surface. The precise setup of phantom was guided by HTMVCT images. After the irradiation, the measured dose distributions on the coronal and sngittal plane were compared with those calculated by the IM planning system for verification. The results were evaluated and the feasibility of the different measuring methods was studied. Results The dose distribution measured by the MatriXX 2DICA was well consistent with that calculated by the treatment planning system. The errors between the measured dose and predicted dose in the selected points were within ±3%. In the comparison of the pixel-segmented ionization chamber versus treatment planning system using the 3 mm/3% γ criteria, the passing ratio of pixels with γ parameter ≤1 was 97.76% and 96.83%, respectively. Conclusions MatriXX is a-ble to measure the absolute and relative dose distributions simultaneously,which can be used for dose verifi-cation of IM planning.

Objective To quantify dose variations of the parotid glands and spinal cord in nasopharyngeal carcinoma (NPC) patients during helical tomotherapy (HT) by using megavolt (MV) CT and planned adaptive application. Methods Five patients with advanced local-regional NPC were treated by HT with a prescription dose of 70 Gy in 35 fractions in primary tumor and involved lymph nodes. Daily MV CT scans were registered with the planning CT images. The parotid glands were re-contoured every 4 fractions to a total of 45 times, and location of the spinal cord were corrected by MVCT IGRT system every 2 fractions to a total of 85 times. The actual doses delivered to these organs were evaluated by using the planned adaptive application software of HT system. Results At the end of therapy, the mean volume of the parotid gland was decreased by 42% (left) and 33% (right) , respectively. The average V1 of the parotid was increased by 26. 0% (left) and 31.4% (right), and the D50 increased by 15. 8% (left) and 17. 3% (right), respectively. The average Dmax of the spinal cord was increased by 1.3%. Conclusions During HT, the parotid glands receive a higher actual dose due to the volume shrinkage, while the Dmax of the spinal cord changes little. By using adaptive radiation therapy technique, constant monitoring anatomic changes of organs at risk and selective replanning are necessary during radiation therapy for NPC.