Monitoring the progression of renal fibrosis by T2-weighted signal intensity and diffusion weighted magnetic resonance imaging in cisplatin induced rat models / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Diffusion weighted imaging (DWI), with the applying of intravoxel incoherent motion model, has showed promising results in obtaining additional information about microperfusion and tubular flow associated with morphologic changes in chronic kidney diseases. The study aims to evaluate the potential of T2-weighted signal intensity (SI) and DWI with mono- and bi-exponential models to reflect the serial changes on cisplatin (CP) induced rat renal fibrosis models.</p><p><b>METHODS</b>Magnetic resonance exams were performed prior to and 2 nd day, 4 th day, 6 th day, 8 th day, 2 nd week, 3 rd week and 4 th week after CP injection at a 3.0T with an animal coil. Besides T2-weighted images (T2WI), DWI of 13 b values from 0 to 1500 s/mm 2 was acquired. Apparent diffusion coefficient (ADC), fluid fraction f, pure diffusivity D and pseudodiffusivity DFNx01 values were calculated. The regions of interest were placed on cortex (CO), outer stripe of the outer medulla (OM) and inner stripe of the outer medulla (OM), parameters were measured and compared among different time points. Five rats were scarified at each time point for pathological examination.</p><p><b>RESULTS</b>OM revealed remarkable hyperintense and broadened before it became an obscure thread, while CO demonstrated moderate hyperintense and IM didn't show significant change on T2WI. On all three stripes, ADC values decreased firstly then kept increasing since the 4 th day; f values decreased on all stripes; D values had a tendency to increase with fluctuations but the changes didn't achieve statistical significance; DFNx01 values increased at the 2 nd day then tended to be steady thereafter. Pathological findings revealed tubules epitheliums swelling followed by inflammation cells infiltration, interstitial fibrosis was observed since the 2 nd week.</p><p><b>CONCLUSIONS</b>All of T2-weighted SI, ADC, and biexponential models parameters vary during fibrotic process; biexponential model is superior to monoexponential model in separating changes of microperfusion together with tubular flow from pure diffusion.</p>

Inhibitory effect of a novel histone deacetylases inhibitor FK228 on human colon cancer HCT-116 cells in vitro and in vivo / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To investigate the inhibitory effects of a novel histone deacetylases inhibitor FK228 on human colon cancer HCT-116 cells in vitro and in vivo, and evaluate its toxicity and side effects.</p><p><b>METHODS</b>The in vitro growth inhibitions of HCT-116 cells by different concentrations of FK228 and 5-Fu for 24, 48 and 72 h were assessed by CCK-8 assay. BALB/c nude mouse models of tumor xenografts were prepared by subcutaneous implantation of tumor tissue, and 4 mg/kg FK228 and 50 mg/kg 5-Fu were i.p. injected, respectively. The inhibitory effects on tumor growth, hematology, and liver and kidney function were evaluated.</p><p><b>RESULTS</b>CCK-8 assay indicated that FK228 had an obvious growth inhibitory effect on HCT-116 cells in a dose- and time-dependent manner. The IC50 of FK228 in HCT-116 cells was 12.05 ng/ml for 48 h, while the IC50 of 5-Fu was 18.92 µg/ml. At 20 days after FK228 and 5-Fu treatment, the tumor volume of the FK228 group was (139.71 ± 44.54)mm(3), significantly lower than that of the 5-Fu group [(282.28 ± 58.81)mm(3)] and that of the model group [(520.65 ± 39.73)mm(3), P < 0.01 for both]. The average tumor weight was (0.07 ± 0.02)g in the FK228 group, significantly lower than that of the 5-Fu group [(0.20 ± 0.08)g, P < 0.01]. The tumor growth inhibition rate of the FK228 group was 73.2%, significantly higher than that of the 5-Fu group (45.8%, P < 0.01). The ALT levels of the FK228 and 5-Fu groups were significantly higher than that of the model group (P < 0.01). The BUN of 5-Fu group was significantly higher than that of the model group (P < 0.01), but the BUN of FK228 group was not significantly different from that of the blank and control groups (P > 0.05 for both). Routine blood test showed that WBC, RBC, Hb and PLT of the 5-Fu group were significantly lower than those of the model group (P < 0.05 for all), but only WBC of the FK228 group was significantly lower than that of the model group (P < 0.05). The pathological examination using HE staining revealed that in the FK228 group, there were fibrosis and inflammatory cell infiltration in the liver tissue, and mild edema of the renal tubules in the kidney. However, in the 5-Fu group there were extensive hepatocyte edema and necrosis in the liver, and evident deformation and necrosis of glomeruli and tubules, and tubular wall thinning in the kidney.</p><p><b>CONCLUSIONS</b>The results of this study indicate that FK228 can more effectively than 5-Fu inhibit the growth of HCT-116 cells in vitro and vivo, and without obvious toxic effect on the kidney and hematology. Its clinical value in colon cancer treatment deserves further investigation.</p>