Objective To explore the main influence factors(heart rate,rotation speed,and reconstruction algorithm)on the image quality of coronary artery with 40 mm VCT(64-detector row helical CT)using a pulsating cardiac phantom.Methods An adjustable pulsating cardiac phantom(GE) containing predetermined simulated coronary arteries was scanned using a 40 mm VCT(GE LightSpeed CT) with cardiac pulsating rates of 40,45,50,55,60,65,70,75,80,85,90,95,100,105,110,and 115 beats per minute(bpm).The variable rotation speeds technique of 0.35 s,0.40 s,and 0.45 s were used, respectively.The raw data were reconstructed using both one-sector and multi-sector reconstruction algorithm at optimal window of the R-R interval.The image quality score(IQS)was evaluated by two radiologists according to the same evaluation standard of reformated image.The correlation between heart rate(HR), roation speed,reconstruction algorithm,and IQS were analyzed.The IQS as independent variable and the HR,rotation speed,reconstruction algorithm as dependent variables were analyzed by multiple linear regression analysis.Restllts The heart rate and the reconstruction algorithm had significant influence on IQS.The rotation speed(0.35s,0.40s,and 0.45s)didn't have significant influence on IQS.There was linear regression relationship between heart rate,reconstruction algorithm and IQS(P

Objective To observe the relationship between apoptosis of K562 cell induced by iron-deprivation and activation of Caspase-3.Methods K562 cells were treated with desferrioxamine(DFO) in different dosages were collected at different time points.K562 cells were labelled with Annexin V/PI,and then the rate of apoptosis was measured by flow cytometry;The activation of Caspase-3 were detected by colorimetric method with pAN labelled substrate;The active protein of Caspase-3 were analyzed by Western blot.Results When K562 cells were treated with different concentrations of DFO,the apoptosis rate and the activity of Caspase-3 increases gradually.When K562 cells were incubated with DFO(50 ?mol/L and 100 ?mol/L) 24 h later,the enzymatic activity of Caspase-3 increases dramatically more than that of control group,and the difference was significantly(P0.05).All those effect above can be counteracted by equal mole concentration of FeCl_3.Conclusion Iron-deprivation maybe induce the apoptosis of K562 cell by chelating intracellular iron and activing Caspase-3.

OBJECTIVETo assess the feasibility of usage of microbubbles conjugated with RGD peptides and contrast enhanced ultrasound (CEU) in detection of tumor angiogenesis.

METHODSLipid microbubbles (MB) were prepared, and the RGD peptides were covalently conjugated to the lipid shell of MB (MB(RGD)). Six nude mice with tumor created by dorsal inoculation of HepG2 tumor cells were used as the test group. Six nude mice without tumor were served as the control group. 10 minutes after bolus injection of MB and MB(RGD) randomly (30 min interval) via a tail vein catheter, CEU was performed on the tumors of the test group and the thigh skeletal muscles of control group. The video intensity (VI) of tumors and the skeletal muscles were measured. The tumors and the skeletal muscles were harvested for immunohistochemical examination.

RESULTSOnly a slight contrast enhancement of the tumor was seen with MB, and the VI was 5.33 ± 1.71. While a remarkable enhancement of the tumor was observed after injection of MB(RGD). The VI was up to 17.03 ± 3.58, 3.18 folds higher as compared with that obtained by injection of MB (P < 0.05). As expected, there were no obvious contrast enhancement of the skeletal muscles with both MB(RGD) and MB. There was a high expression of αvβ3-integrin in tumor neovascular endothelium, however, no apparent expression of αvβ3-integrin was observed in the skeletal muscle vascular endothelium.

CONCLUSIONCEU with MB(RGD) can be used to effectively evaluate the angiogenesis of tumors, and it may greatly contribute to the early judgement of the nature of tumor.

Animals ; Cell Line, Tumor ; Contrast Media ; Endothelium, Vascular ; diagnostic imaging ; metabolism ; Female ; Humans ; Integrin alphaVbeta3 ; metabolism ; Liver Neoplasms ; blood supply ; diagnostic imaging ; metabolism ; pathology ; Male ; Mice ; Mice, Nude ; Microbubbles ; Muscle, Skeletal ; blood supply ; Neoplasm Transplantation ; Neovascularization, Pathologic ; diagnostic imaging ; metabolism ; pathology ; Oligopeptides ; Ultrasonics ; methods ; Ultrasonography

No abstract available.
Hyalin* ; Salivary Glands*

To explore a rapid and easy method to detect labile iron of pool (LIP) in cells, HL-60 and K562 cells were cultured at a concentration 1 x 10(6)/ml in RPMI 1640 containing 10% heat-inactivated fetal bovine serum. The iron deprivation was induced by adding desferrioxamine (DFO) 10 - 100 micromol/L for 0 - 48 hours. The intracellular LIP was measured by probe calcein-AM. Calcein fluorescence was monitored in 1420 multilabel counter. The results indicated that when HL-60 and K562 cells were incubated with different concentrations of DFO, the calcein fluorescence intensity was higher than that of control group at 12, 24 and 48 hours (P < 0.05). Fluorescence value of representing LIP in DFO groups was lower than that in the control group. In conclusion, DFO can decrease LIP in leukemia cells. The approach used in this study may provide a simple and reliable method for detection of intracellular iron homeostasis.
Cation Transport Proteins ; antagonists & inhibitors ; biosynthesis ; metabolism ; Deferoxamine ; pharmacology ; Fluoresceins ; Fluorescent Dyes ; HL-60 Cells ; Humans ; Iron ; metabolism ; Iron Chelating Agents ; analysis ; metabolism ; Iron-Regulatory Proteins ; metabolism ; K562 Cells

OBJECTIVETo propose arectal toxicity prediction method based on deformable surface dose accumulation.

METHODSThe clinical data were collected retrospectively from 42patients receiving radiotherapy for cervical cancer. With the first fraction as the reference, the other fractions of rectum surface were registered to the reference fraction to obtain the deformation vector fields (DVFs), which were used to deform and sum the fractional rectal doses to yield the cumulative rectal dose. The cumulative rectal dose was flattened via 3D-2D mapping to generate a 2D rectum surface dose map. Two dosimetric features, namely DVPs and DGPs were extracted. Logistic regression embedded with sequential forward feature selection was used as the prediction model. The predictive performance was evaluated in terms of the accuracy, sensitivity, specificity, and the area under the receiver operating characteristic (ROC) curve (AUC).

RESULTSSignificant improvements for rectum surface DIR were achieved. The best predictive results were achieved by using both DVPs and DGPs as the features with a sensitivity of 79.5%, a specificity of 81.3% and an AUC of 0.88.

CONCLUSIONThe proposed method is feasible for predicting clinical rectal toxicity in patients undergoing radiotherapy for cervical cancer.

OBJECTIVETo study the role of O(6)-methylguanine-DNA methyltransferase (hMGMT) in the development of human lung cancer.

METHODSReverse transcription-polymerase chain reaction (RT-PCR) method was applied to measure hMGMT mRNA expression in 150 lung cancer specimens, 40 normal lung tissues, and in the peripheral mononuclear blood cells from 50 lung cancer cases and 50 normal controls. The protein expressions of p53, C-MYC and K-RAS were assessed by immuno-histochemistry. The effects of some exposure factors on the expression of hMGMT gene were analyzed. The relationships between hMGMT gene and cancer related genes p53, C-MYC and K-RAS were investigated.

RESULTSThe mRNA of hMGMT was low or absent in 49 of 150 (32.7%) lung cancer specimens, whereas 2 of 40 (5%) normal lung tissues had reduced the levels of hMGMT mRNA. The low expression of hMGMT seemed to be a risk factor of lung cancer, with a OR of 9.22 (2.05-57.65). Reduced expression levels of hMGMT mRNA were observed in 10 of 50 (20%) lung cancer patients' peripheral mononuclear blood cells, and 2 of 50 (4%) blood cells among normal controls. When investigating the exposure factors which affecting the expression of hMGMT gene, we noticed that smoking was suppressing the expression of hMGMT gene. Interestingly, over-expression of K-RAS oncogene was significantly correlated with low expression of hMGMT (P < 0.05). However, the expressions of p53 and C-myc were not correlated with the status of hMGMT gene.

CONCLUSIONhMGMT might play an important role in the development of human lung cancer. Low expression of hMGMT gene seemed to be a risk factor for lung cancer which could be used as a valuable biomarker on susceptibility of human lung cancers.

Adult ; Aged ; Biomarkers, Tumor ; Carcinoma, Squamous Cell ; enzymology ; genetics ; China ; epidemiology ; DNA Repair ; genetics ; Female ; Genes, ras ; genetics ; Humans ; Lung Neoplasms ; enzymology ; genetics ; Male ; Middle Aged ; O(6)-Methylguanine-DNA Methyltransferase ; biosynthesis ; genetics ; metabolism ; Point Mutation ; RNA, Messenger ; biosynthesis ; genetics ; Smoking ; adverse effects ; ras Proteins ; biosynthesis ; genetics

OBJECTIVETo study the therapeutic effects of combined anterior-posterior (small incision or micro-incision) approach for complex tibial plateau and posterior condylar fractures.

METHODSFrom 2000 to 2008, 79 patients (81 limbs) with complex tibial plateau and posterior condylar fractures were reviewed. There were 45 males and 34 females, ranging in age from 19 to 66 years, with an average of 40.6 years. Thirty-nine limbs were treated using small incision through combined anterior-posterior approach, in which 13 limbs were Schatzker type IV, 15 limbs were type V ,and 11 limbs were type VI. Other 42 limbs were treated using micro-incision through combined anterior-posterior approach, in which 18 limbs were Schatzker type IV, 16 limbs were type V, and 8 limbs were type VI. The Rasmussen scores for knee joint and radio scores were used to evaluate therapeutic effects after the treatment. The complications such as cutaneous necrosis and incision infection were observed.

RESULTSAll the patients were followed up. According to Rasmussen criterion, in small incision group, 16 limbs got an excellent result, 13 good, 7 fair and 3 bad; in micro-incision group,above data were 19, 11, 8 and 4 respectively. Comparison between the two groups, P = 0.924. Comparison of complications such as cutaneous necrosis and incision infection: in small incision group,10 limbs had the complications, and in micro-incision group were 4 limbs; the occurrence rate of small incision group were higher than that of micro-incision group (P = 0.047).

CONCLUSIONThere are no significant differences between the two groups in the knee joint function rehabilitation; however, there is smaller rate for cutaneous necrosis and incision infection in micro-incision group.

Adult ; Aged ; Ankle Injuries ; surgery ; Case-Control Studies ; Female ; Fracture Fixation ; methods ; Humans ; Knee Joint ; physiopathology ; Male ; Middle Aged ; Postoperative Complications ; epidemiology ; Retrospective Studies ; Tibial Fractures ; surgery

OBJECTIVETo study the genetic polymorphisms of the mitochondrial DNA (mtDNA) control region in Chengdu Han population.

METHODSSequence polymorphisms of the mtDNA control region, hypervariable regions I and II from 100 unrelated Chinese Hans were determined by PCR and direct sequencing.

RESULTSSequences of 404 nucleotides for hypervariable region I and 379 nucleotides for region II were obtained. Ninety-two and fifty variable sites were revealed in region I and region II respectively as compared to the reference sequence, and a total of 97 different genetic patterns from both the regions I and II were determined. The probability of identity was estimated at 1.84% for region I, 1.94% for region II, and 1.18% for both the regions.

CONCLUSIONThese results suggest that sequence polymorphism of mtDNA control region would be very useful in forensic practice as a marker for individual identification.

Base Sequence ; China ; DNA, Mitochondrial ; chemistry ; Genetics, Population ; Humans ; Molecular Sequence Data ; Mutation ; Polymorphism, Genetic

This study was purposed to explore the biological effects suppressing growth and inducing apoptosis of Chinese medicine compound FFJZ on leukemia cell line K562 and its possible mechanisms of FFJZ. The growth status of K562 cells cultured in vitro was determined by trypan blue exclusion test; the suppressive effect of FFJZ on K562 cells was assayed by MTT method; the inducing apoptosis of FFJZ on K562 cells was detected by flow cytometry. The results showed that after K562 cells were treated with FFJZ in certain concentration range, the inhibited rate of FFJZ on K562 cell growth was remarkably increased along with enhancement of FFJZ, the IC(50) value of FFJZ on K562 cells was 5.6 mg/ml after treatment for 48 hours. At 4 mg/ml of FFJZ the early apoptosis predominated in K562 cells, at 8 mg/ml of FFJZ the late apoptosis ratio significantly increased. As compared with control group without FFJZ, there was significant difference (p < 0.01). It is concluded that the FFJZ in range of certain concentration can suppress growth and proliferation of K562 cells and induce their apoptosis in concentration-dependent manner, the mechanism of which may be associated to inducing apoptosis of K562 cells.
Apoptosis ; drug effects ; Cell Proliferation ; drug effects ; Drugs, Chinese Herbal ; pharmacology ; Humans ; K562 Cells