Objective To observe the effects of granulocyte colony stimulating factor (G-CSF) on electrophysiological properties of post-infarct ventricles.Methods Sixty-seven survival Wistar rats were divided into 4 groups:Sham group,Control group,MI early G-CSF group (E-G) and MI delay G-CSF group (D-G) after ligation of the left coronary artery as myocardial infarction model.Monophasic action potential(MAP) was recorded by absorption electrode in ex vivo perfused rat hearts.Effective refractive period(ERP),sinus cardiac length (SCL),action potential amplitude (APA),maximal depolariged (Vmax),ventricular fibrillation threshold(VFF) and ventricular fibrillation duration(VFD) were measured.Results The electrophysiological parameters (SCL,VFT,VFD,APA,ERP/MAP90,dispersion of ERP and MAP90) of the E-G group were improved significantly (all P ＜ 0.05) at day 7 post MI.Improvement in SCL,dispersion of ERP and MAP 90 were found in the D-G group as well at day 7 post MI (all P ＜ 0.05).Substained improvement in electrophysiological parameters were found in the E-G group at 3 months after MI (P ＜0.05).Besides SCL,APA,Vmax and dispersion of MAP90,all other parameters in the D-G group were similar to that of the control group with no statistical significance and even had a tendency of deterioration in ERP and MAP90 3 months after MI.Conclusion G-CSF intervention could improve electrophysiological properties of ischemic ventricles.Early G-CSF intervention showed better outcomes compared to delay G-CSF intervention on electrical remodeling ischemia myocardiumwhich may have effect on reducing the development of ventricular arrhythmia.

Objective:To investigate the value of dynamic contrast-enhanced MRI enhancement amplitude for qualitative diagnosis of suspicious residual enhancing lesions after neoadjuvant therapy (NAT) in breast cancer.Methods:In total, 168 suspicious residual enhancing lesions of 168 patients who received NAT at Peking University Cancer Hospital from January 2015 to June 2016 were retrospectively analyzed and divided into non-residual cancer group ( n=59) and residual cancer group ( n=109) according to pathological findings. Then 168 suspicious residual enhancing lesions were stratified according to molecular subtype and baseline enhancing morphology. According to the breast imaging reporting and data system, the morphology of enhancing lesions, the margin of mass-like enhancing lesions, and the distribution of non-mass-like enhancing lesions on MRI before NAT were recorded. The second phase (1 min 45 s-2 min after contrast injection) was used as the early phase, and the fifth phase (5-6 min after contrast injection) was used as the late phase to measure the signal intensity and time-signal intensity curve (TIC) of suspicious residual enhancing lesions, and the signal enhancement ratio (SER) was calculated. Independent sample t-test, Mann-Whitney U test and χ 2 test were used to compare the difference of SER and clinical features between the non-residual and residual cancer groups. The receiver operator characteristic curve was used to analyze the diagnostic efficacy of SER to determine residual cancer. Results:There are statistically significant differences in invasive ductal carcinoma grade, hormone receptor status, the morphology of enhancing lesion on baseline MRI and TIC type between non-residual and residual cancer groups ( P<0.05). The SER values of the non-residual cancer group in the early [31% (23%, 61%)] and late (72%±43%) enhanced phases were significantly lower than those of the residual cancer group [49% (28%, 71%), 88%±38%, Z=-2.26, t=-2.43, P=0.024, 0.016, respectively]. Among suspicious residual enhancing lesions with hormone receptor negative status and single mass-like morphology, the SER values of the non-residual cancer group in the early (33%±16%) and late [64% (42%, 74%)] enhanced phases were significantly lower than those of the residual cancer group [59%±30%, 84% (77%, 106%), t=-2.86, Z=-3.17, P=0.008, 0.001, respectively]. The area under the curve values of SER in differentiating suspicious residual enhancing lesions were statistically different between early and late enhanced phases (0.606 and 0.637, respectively, Z=2.16, P=0.031). Conclusion:For breast cancer after NAT, it is difficult to determine the suspicious residual enhancing lesions on MRI subjectively, especially the hormone receptor negative lesions with single mass, SER can be used as an auxiliary diagnostic method, and it is necessary for the analysis of late enhancement.

Objective To investigate the variation of procalcitonin(PCT) in blood and tissue level of acute pancreatitis rats and probe its significant. Methods One hundred and two male Wistar rats were randomly divided into control group ( n = 6 ), lipopolysaccharide group ( LPS, n = 24 ), acute edematous pancreatitis (AEP) group ( n = 24), acute necrotizing pancreatitis (ANP) group ( n = 24), AN P + LPS group ( n = 24). Subcutaneous injection of cerulein was used for AEP induction, while ANP model was induced by retrograde injection of sodium taurocholate into the biliary and pancreatic duct. The rats were sacrificed at 3,6, 18 and 24 hours after model induction. Pancreatic tissue was harvested and the pathological scores were assessed. Levels of PCT in serum, liver, lung, spleen, pancreas, small intestine, large intestine tissue was harvested and tissue levels of PCT were determined. Results AEP and ANP models were established successfully. At 6 h, the serum levels of PCT in control group, LPS group, AEP group, ANP group and ANP +LPS group were (0.0144 ±0.0082) ng/ml, (0. 1722 ±0.0449) ng/ml,(0.4751 ±0.0572) ng/ml, (0.7070 ±0. 1040) ng/ml and ( 1. 1960 ±0.8644) ng/ml, respectively; and the difference was statistically significant (P < 0.05 ). PCT could be detected in liver, lung, spleen, pancreas, small intestine and large intestine tissue of normal rats. PCT levels in liver and pancreas of ANP group were not statistically different, but the PCT levels in lung, spleen, and large intestine tissue significantly decreased, and the corresponding values were (5.63 ±0.62) ng/ml vs. (6.85 ±0.46) mg/ml, (4.73 ±1.27) mg/ml vs. (6.88 ±0.37) ng/ml, (1.08 ±0.52) ng/ml vs. (4.12 ± 1.02) ng/ml (P <0.01 ). However, the PCT levels in small intestine significantly increased, which were (2.51 ±0.90) ng/ml vs (0.98 ±0. 12) ng/ml (P<0. 01). Conclusions Serum PCT level was associated with the severity of AP and infection; the changes of PCT levels in different tissues may be related with the changes of organ's function.