Vascular endothelial growth factor attenuates hepatic sinusoidal capillarization in thioacetamide-induced cirrhotic rats

AIM: To investigate the effect of vascular endothelial growth factor (VEGF) transfection on hepatic sinusoidal capillarization. METHODS: Enhanced green fluorescent protein (EGFP)/ VEGF transfection was confirmed by immunofluorescence microscopy and immunohistoche-mistry both in primary hepatocytes and in normal liver. Cirrhotic rats were generated by thioacetamide (TAA) administration and then divided into a treatment group, which received injections of 400 μg of plasmid DNA encoding an EGFP- VEGF fusion protein, and a blank group, which received an equal amount of normal saline through the portal vein. The portal vein pressure was measured in the normal and cirrhotic state, in treated and blank groups. The average number of fenestrae per hepatic sinusoid was determined using transmission electron microscopy (TEM), while the relative abundance of VEGF transcripts was examined by Gene array. RESULTS: Green fluorescent protein was observed in the cytoplasms of liver cells under immunofluorescence microscopy 24 h after transfection with EGFP/VEGF plasmid in vitro. Staining with polyclonal antibodies against VEGF illustrated that hepatocytes expressedimmunodetectable VEGF both in vitro and in vitro. There were significant differences in the number of fenestrae and portal vein pressures between normal and cirrhotic rats (7.40 ± 1.71 vs 2.30 ± 1.16 and 9.32 ± 0.85 cmH2O vs 17.92 ± 0.90 cmH2O, P < 0.01), between cirrhotic and treated rats (2.30 ± 1.16 cmH2O vs 4.60 ± 1.65 and 17.92 ± 0.90 cmH2O vs 15.52 ± 0.93 cmH2O, P < 0.05) and between the treatment group and the blank group (4.60 ± 1.65 cmH2O vs 2.10 ± 1.10 cmH2O and 15.52 ± 0.93 cmH2O vs 17.26 ± 1.80 cmH2O, P < 0.05). Gene- array analysis revealed that the relative abundance of transcripts of VEGF family members decreased in the cirrhotic state and increased after transfection. CONCLUSION: Injection of a plasmid encoding VEGF through the portal vein is an effective method to induce the formation of fenestrae and decrease portal vein pressure in cirrhotic rats. Therefore, it may be a good choice for treating hepatic cirrhosis and portal hypertension.

Clinical significance of nerve growth factor and tropomyosin-receptor-kinase signaling pathway in intrahepatic cholangiocarcinoma

AIM:To investigate the correlation between nerve growth factor-tropomyosin-receptor-kinase(NGF-TrkA)signaling pathway and prognosis in intrahepatic cholangiocarcinoma(IHCC).METHODS:NGF and TrkA expression in 83 samples of IHCC was assessed by immunohistochemistry.Correlations between NGF-TrkA expression and clinicopathological features were analyzed byχ2 test.Moreover,we evaluated the association between NGF-TrkA and overall survival by univariate and multivariate analysis.With experiments in vitro,we investigated the crucial role of NGF-TrkA on proliferation and invasion of IHCC cells with recombinant NGF-βstimulation.RESULTS:We found that NGF and TrkA expression was significantly related with differentiation(P=0.024)and intraneural invasion(P=0.003),respectively.Additionally,double higher expression of NGF and TrkA was identified as an independent prognostic factor in IHCC(P=0.003).Moreover,we demonstrated that NGF-TrkA signaling pathway can promote IHCC proliferation and invasion.CONCLUSION:NGF-TrkA double higher expression is an independent prognostic factor in IHCC.NGF-TrkA pathway can promote IHCC progression,indicating that NGF-TrkA may become a potential drug target.

Application of air insufflation to prevent clinical pancreatic fistula after pancreaticoduodenectomy

AIM:To introduce an air insufflation procedure and to investigate the effectiveness of air insufflation in preventing pancreatic fistula(PF).of 185 patients underwent pancreaticoduodenectomy(PD)at our institution,and 74 patients were not involved in this study for various reasons.The clinical outcomes of 111 patients were retrospectively analyzed.The air insufflation test was performed in 46 patients to investigate the efficacy of the pancreaticojejunal anastomosis during surgery,and 65 patients who did not receive the air insufflation test served as controls.Preoperative assessments and intraoperative outcomes were compared between the 2 groups.Univariate and multivariate analyses were performed to identify the risk factors for PF.RESULTS:The two patient groups had similar baseline demographics,preoperative assessments,operative factors,pancreatic factors and pathological results.The overall mortality,morbidity,and PF rates were1.8%,48.6%,and 26.1%,respectively.No significant differences were observed in either morbidity or mortality between the two groups.The rate of clinical PF(grade B and grade C PF)was significantly lower in the air insufflation test group,compared with the nonair insufflation test group(6.5%vs 23.1%,P=0.02).Univariate analysis identified the following parameters as risk factors related to clinical PF:estimated blood loss;pancreatic duct diameter≤3 mm;invagination anastomosis technique;and not undergoing air insufflation test.By further analyzing these variables with multivariate logistic regression,estimated blood loss,pancreatic duct diameter≤3 mm and not undergoing air insufflation test were demonstrated to be independent risk factors.CONCLUSION:Performing an air insufflation test could significantly reduce the occurrence of clinical PF after PD.Not performing an air insufflation test was an independent risk factor for clinical PF.