BACKGROUND: An effective method to enhance the accuracy and sensitivity of magnetic resonance imaging (MRI) is to select a targeted contrast agent. OBJECTIVE: To prepare gadopentetic acid -polybutylcyanoacrylate nanoparticle (Gd-PBCA-NP) and to investigate its liver-targeted values in animal experiments.DESIGN, TIME AND SETTING: A comparative observation was performed at the Laboratory of Department of RadiologicelCenter, Nanfang Hospital between September 2004 and January 2005. MATERIALS: Gd-PBCA-NPs were prepared by anionic emulsion polymerization. METHODS: A total of 18 Wistar rats were randomly divided into 3 groups, with 6 rats per group: Gd-DTPA, PBCA-NP, and Gd-PBCA-NP. Following caudal venepuncture (catheter remained), rats received 0.1 mmol/kg Gd-DTPA, 10 mL/kg PBCA-NP, or 10 mL/kg Gd-PBCA-NP. MRI scans (coronal and transverse) were performed prior to and after different enhancement protocols using a head coil for transmission and reception of the signal. Immediately after contrast medium injection, dynamic data of each group were acquired at 5, 15, 30, 60, and 120 minutes using imaging parameters the same as for the pre-contrast images. MAIN OUTCOME MEASURES: The morphology of Gd-PBCA-NPs was observed using transmission electron microscope. The size and the index of size distribution were measured through the use of laser granulometer (Malvern-3000HS). The Gd ion concentration in the dialysate was determined by inductively coupled plasma atomic emission spectroscopy for calculation ofencapsulation efficiency and loading capacity of Gd-PBCA-NP. The enhanced rate of the liver at each time point was calculated. RESULTS: The morphology of Gd-PBCA-NPs was spherical shape with core-shell structure and without adherence between particles. The average size of Gd-PBCA-NPs was 65.7 nm, and the index of size distribution was 0.09 measured by dynamic light scattering. The average encapsulation efficiency and loading capacity of Gd-PBCA-NPs were 81.97% and 51.23%, respectively. After intravenous injection of Gd-DTPA, the enhanced rate of the liver was 35.2% and 48.6% at 5 and 15 minutes respectively and the kidney was obviously enhanced; at 30 minutes, the enhancement of the liver recovered to normal level. After intravenous injection of Gd-PBCA-NPs, the average enhanced rate of the liver was 3.4%, 22.7%, 36.1%, 56.4%, and 24.8% at 5, 15, 30, 60, and 120 minutes accordingly. After intravenous injection of PBCA-NP, the enhancement of the liver was not found. CONCLUSION: Gd-PBCA-NPs can be taken as liver-targeted MRI contrast agents and have potential application value in MRI.

Objective To evaluate the dynamic imaging alteration of radiation-induced hepatic injuries after stereotactic radiotherapy (SRT) in hepatocellular carcinoma.Methods 18 healthy New Zealand white rabbits inoculated VX_2 carcinoma underwent 40 Gy SRT and divided into three groups randomly.The rabbits underwent identical plain and enhanced MR imaging after SRT 3 weeks,9 weeks and 20 weeks respectively. The signal-to-noise ratios of irradiation area and the surrounding normal liver on T_1WI and T_2WI imaging were calculated;The percentage enhancement of the hepatic injuried areas and the surrouding livers after Gd-DTPA enhanced was also calculated.Results After radiotherapy three weeks, the signal-to-noise ratios of irradiation areas on T_1WI and T_2WI were no difference between normal liver tissue and irradiation area; there were significant difference between normal liver tissues in radiotherapy nine weeks and twenty weeks; The difference in the signal-to-noise ratios of irradiation area were significant between after three weeks and nine weeks, twenty weeks. There were no difference in the signal-to-noise ratios of irradiation area between nine weeks and twenty weeks.The percentage enhancement of the hepatic injuries area have significant difference in arterial phase between three weeks and twenty weeks and between nine weeks and twenty weeks;The difference in portal and delay phase were significant between three weeks and nine weeks, twenty weeks, there were no difference between nine weeks and twenty weeks.Conclusion Dynamic enhanced and unenhanced MR imaging can reflect the pathological background of radiation-induced hepatic injuries in different phases.

Objective To evluate Feridex-enhanced MRI in the diagnosis of focal hepatic lesions. Methods Conventional plain and Feridex-enhanced MR scanning was performed in 20 cases with suspected hepatic neoplasm.The number of lesions on T 2WI ,and the signal intensity of liver and lesions demonstrated on plain and enhanced scans were observed and analyzed.Results After the injection of Feridex,the signal intensity of normal liver tissue reduced significantly,while the signal intensity of lesions showed no marked changes,Feridex-enhanced MRI clearly displayed more lesions on T 2WI than plain scanning did.Conclusion Feridex-enhanced MRI is very sensitive in detecting focal hepatic lesions.

BACKGROUND:Sensitivity of diagnoses differentiating smaller nodes of splenic metastasis (＜ 1 cm) from CT and MRI is poor. So whether superparamagnetic iron oxide can enhance magnetic resonance imaging (MRI) of splenic VX2 tumor in rats need to be further studied.OBJECTTVE: To establish splenic VX2 tumor models, investigate MRI scanning combining with superparamagnetic iron oxide of specific reticuloendothelial system, and study the diagnostic significance of superparamagnetic iron oxide-enhanced MR images on splenic metastases.DESIGN: Duplicated-measured animal study.SETTING: Medical Imaging Center, Nanfang Hospital of the Southern Medical University.MATERIALS: The experiment was carried out in the Medical Imaging Center (Military Key Laboratory), Nanfang Hospital of the Southern Medical University from May 2005 to March 2006. A total of 25 adult SD rats, of either gender, weighing 200-300 g, were selected in this study. The animal experiment had got confirmed consent from local ethic committee. All rats were randomly divided into tumor group (n =20) and blank control group (n =5).METHODS: Models of VX2 tumor in spleen were established successfully. The images obtained before and after administration of superparamagnetic iron oxide. T1-weighted image(T1WI) (450/12 ms) and T2-weighted image(T2WI)(4 000/128 ms) were used to scan sequences. The imaging parameters of various tissues were analyzed before and after superparamagnetic iron oxide-enhanced MRI scanning. Rats in the blank control group were not used to establish models and the sequences were scanned as the same as those in the experimental group.MAIN OUTCOME MEASURES: Signal characteristics of various tissues before and after before and after superparamagnetic iron oxide-enhanced MRI scanning.RESULTS: Eight out of 20 rats died in the tumor group and other 12 and 5 rats in the control group were involved in the final analysis. MR scanning indicated that 8 rats in the tumor group had splenic VX2 tumor. ① On plain MR scanning T1-weighted splenic VX2 tumor showed hypointensity or isointensity which approximated to the signal intensity (SI) of splenic parenchyma. All lesions had been not displayed well. ② On superparamagnetic iron oxide enhancement T2WI sequence the SI of splenic parachyma decreased obviously with percentage of signal intensity loss (PSIL) was 56.11%,But the SI of tumor was not evidently change with PSlL was 1.90%. Nevertheless the signal-to-noise ratio (SNR) of normal splenic parenchyma around the lesions had obviously difference (P ＜ 0.001) comparatively. So the contrast between tumor and spleen increased, and tumor displayed more clear. Moreover the contrast-to-noise (CNR) between VX2 tumor and splenic parenchyma had an evidently difference with before and after admininstration of superparamagnetic iron oxide (P ＜ 0.001 ).CONCLUSION: On superparamagnetic iron oxide enhancement T1WI sequence the contrast of tumor-to-spleen is poor.So it is not good to characterize the lesions in spleen. On superparamagnetic iron oxide enhanced T2WI the contrast degree of lesions increased obviously. Consequently, superparamagnetic iron oxide-enhanced T2WI MRI scanning can improve the rate of detection and characterization in lesions of spleen.

Objective:To study the effects of the conditioned medium (CM) from human lung adenocarcinoma cell line A549 on the viability and apoptosis of human umbilical vein endothelial cells (HUVECs) and the role of PI3K-Akt signaling pathway in the process. Methods:HUVECs were cultured with CM of A549 cells. Cell viability was detected by XTT assay. The morphological changes of HUVECs were analyzed by Hoechst 33258 staining and fluorescence microscopy. The apoptosis was detected by flow cytometry. Expression levels of total Akt and phosphorylated Akt were assessed by Western blotting. PI3K inhibitors wortmannin(WT)and Akt1 siRNA(siAkt1)were used to block PI3K-Akt signaling pathway. The mRNA transcription of Akt subtype was determined by RT-PCR.Results:A549 CM significantly increased cell viability after 24 h treatment (P=0.037) and inhibited apoptosis (P=0.001) of HUVECs. CM time-dependently activated phosphorylation of Akt. Akt was phosphorylated at 15 min after CM treatment and reached the peak at 30 min and then tended to decline. Both WT and siAkt1 blocked the effects of CM. Conclusion:The CM of A549 cells increased the survival and inhibit the apoptosis of HUVECs. Akt1 played a significant role in the process.

OBJECTIVE: To observe the clinical effect of perforated bovine amnion combined with recombinant bovine basic fibroblast growth factor (rb-bFGF) on degree Ⅱ burn wounds.METHODS: A total of 43 patients with small and medium-size thermal burn were collected, and the area of testing wound was 1% -2%. The wounds with the same nature were divided into three groups: perforated bovine amnion (treatment group), bovine amnion (control 1 group), and vaseline gauze dressing (control 2 group). All the three groups combined with rb-bFGF. RESULTS: Compared with control 1 group (P < 0.01) and control 2 group (P < 0.05), the treatment group could obviously decrease the healing time of deep degree Ⅱ burn wounds. For superficial degree Ⅱ burn wounds, compared with the control 2 group, the treatment group could also decrease the healing time; however, there was no significant difference between treatment group and control 1 group (P > 0.05). Dressing was not changed frequently, and the pain was relieved. Rash or other adverse effects were not detected in the three groups.CONCLUSION: The combination of perforated bovine amnion and rb-bFGF can obviously promote the healing of burn wounds.

Objective To evaluate the diagnostic value of diffusion tensor imaging(DTI)and diffusion kurtosis imaging(DKI)in marchiafava bignami disease(MBD)of chronic alcoholism.The ROC curve was used to analyze the diagnostic significance of each parameter (FA,ADC and MK values).Methods Sixty-eight patients with chronic alcoholism were enrolled in this study,sixty normal middle-aged people were selected as the control group.The ROC curves of differentparameters in the diagnosis of chronic alcoholism were drawn,after whichthe thresholds were determined to evaluate the clinical significance of FA,ADC and MK values in the diagnosis of the disease.Results The FA and MK values of patients with chronic alcoholism were found to be significantly lower than those of the normal control group(P<0.01).ROC curve analysis showed that the critical values for the FA,ADC and MK parameters were 0.274,5.55 and 0.874,respectively.Conclusion Compared with the ADC and MK parameters,FA parameter has a high clinical significance in the diagnosis of MBD.

Objective ToexplorethevalueofMR DKIinevaluationofmicrostructuredamageincervicalspinalcordinjury(CSCI) Methods 32casesofCSCIpatientsconfirmedbyclinicalexaminationand20casesofhealthycontrolgroupwereinvestigatedbyconventional MRIandDKIexamination.AccordingtoT2WIsignal,theinjurygroupweredividedintoA,Bgroup,Agroupofhighsignalgroup(n＝14)andBgroupofnegativegroup (n＝18).A,BgroupsandcontrolgroupweremeasuredbyFA,meandiffusivity(MD)and mean kurtosis(MK)valuesatdifferenttimes (acute,4 weeksafterinjury,2to3 monthsafterinjury)andthedata wereanalyzedby SPSS17.0statisticalsoftware.TheROCcurvewasusedtoevaluatetheabilityofdifferentparametersindiagnosingCSCI.Results In A,BgroupsFAvaluesdecreasedearlyandincreasedgradually,butwerealwayslowerthanthecontrolgroup,andthedifferencewas statisticallysignificant(P＜0.001).InAgroup MDvalueincreasedearlyanddecreasedgradually,butwashigherthanthecontrol group (P＜0.001).InAgroup MKvaluedecreasedearlyandincreasedsignificantly(P＜0.001).InBgroup MDvalueincreasedand MKvaluedecreasedintheacutephase(P＜0.001),lateron MDand MKvaluesgraduallytendtothecontrolgroup,thedifference wasnotstatisticallysignificant(P＞0.05).Conclusion DKIcannoninvasivelyreflectthemicroGdamageofCSCI,whichcannotbedisplayed byconventionalMRIfortheearlydetectionofspinalcordabnormalities.TheFAvalueisofhighdiagnosticvalue.

Objective To investigate and analyze the application of narcotic drugs in the our hospital from 2011 to 2013, in order to provide references for rational use of narcotic drugs in clinical practice. Methods The application da-ta of narcotic drugs in our hospital from 2011 to 2013 were collected and analyzed from the hospital information sys-tem, adverse reactions of narcotic drugs were collected from clinical pharmacy support. Results The consumption sum of narcotic drugs increased year by year. Pethidine injection and tablet consumption were the largest, morphine agents consumption were relatively stable, fentanyl and remifentanil consumption also increased year by year, narcotic drugs had different adverse reactions. Conclusion With the implementation of“three-step ladder for cancer pain” and estab-lishment of“good pain management ward”, the utilization of narcotic drugs in our hospital will be more reasonable.