ABSTRACT
Objective To investigate the change trends of apparent diffusion coefficient (ADC) values under different b values of diffusion‐weighted imaging(DWI) in acute cerebral infarction .Methods The patients with acute celebral infarction were selected as the experimental group and the normal volunteers as the control group .The 5 different diffusion gradients were used ,including b=200 s/mm2 ,b=400 s/mm2 ,b=600 s/mm2 ,b=800 s/mm2 and b=1 000 s/mm2 .The two pairs of 20 cases of acute cerebral in‐farction and 20 healthy volunteers were performed the DWI scanning for detecting the ADC value under different b values .The ADC values in the two groups were statistically analyzed by using one‐way anova .Results In 5 different b values ,the ADC values in the case group was 0 .64 ,0 .59 ,0 .55 ,0 .47 and 0 .41 respectively ,which in the control group were 1 .04 ,0 .99 ,0 .92 ,0 .85 and 0 .78 re‐spectively ,the differences between the two groups were statistically significant ,moreover with the b value increase ,the ADC value had a decreasing trend(P< 0 .01) .Conclusion The ADC value in the patients with acute cerebral infarction is significantly de‐creased ,the ADC values are different under different b values of DWI ,moreover which shows the significantly negative correlation trend .
ABSTRACT
Objective To investigate whether chlorophyllin could protect human umbilical vein endothelial cell (HUVEC) against oxidative damage by inducing the expression of heme oxygenase-1 (HO-1) and to explore the underlying mechanism.Methods The cellular protection of chlorophyllin against oxidative damage was detected by cell-survival assay with flow cytometry.The level of free radicals was detected directly by electron spin resonance spectra.The induced expression of HO-1 was shown by RT-PCR,Western blot,immunofluorescence confocal laser microscopy and enzymatic activity test.Whether the activation of PI3K/Akt pathway was involved was detected by Western blot.Results Chlorophyllin could protect HUVEC against oxidative damage caused by H2O2 via scavenging the excessive free radicals.Chlorophyllin treatment could induce expression of HO-1 in a dose- and time-dependent manner.The activation of PI3K/Akt pathway was required in the induction of HO-1.LY294002,the specific inhibitor of PI3K,could suppress the activation of PI3K/Akt and the induced expression of HO-1 in a dose-dependent manner.Conclusions Chlorophyllin shows cellular protection against oxidative damage by counteracting the excessive free radicals.Up-regulation of HO-1 expression plays a pivotal role in the protection of chlorophyllin,while the activation of PI3K/Akt signaling pathway is required in the induction of HO-1.