Non-alcoholic fatty liver disease:An early mediator predicting metabolic syndrome in obese children?

AIM:To investigate if non-alcoholic fatty liver disease (NAFLD) is an early mediator for prediction of metabolic syndrome,and if liver B-ultrasound can be used for its diagnosis.METHODS:We classified 861 obese children (6-16 years old) into three subgroups:group 0 (normal liver in ultrasound and normal transaminases);group 1 (fatty liver in ultrasound and normal transaminases);and group 2 (fatty liver in ultrasound and elevated transaminases).We measured the body mass index,waist and hip circumference,blood pressure,fasting blood glucose,insulin,homeostasis model assessment of insulin resistance (HOMA-IR),whole-body insulin sensitivity index (WBISI),lipid profile and transaminases in all the participants.The risk of developing metabolic syndrome (MS) was assessed according to the degree of liver fatty infiltration based on the B-ultrasound examination.RESULTS:Among the 861 obese children,587 (68.18%) were classified as having NAFLD,and 221 (25.67%) as having MS.The prevalence of MS in NAFLD children (groups 1 and 2) was 37.64% (221/587),which was much higher than that in non-NAFLD group (group 0,12.04%) (P < 0.01).There were significantly higher incidences concerning every component of MS in group 2 compared with group 0 (P < 0.05).The incidence of NAFLD in MS patients was 84.61% (187/221),which was significantly higher than that of hypertension (57.46%,127/221) and glucose metabolic anomalies (22.62%,50/221),and almost equal to the prevalence of dyslipidemia (89.14%,197/221).Based on the B-ultrasound scales,the presence of moderate and severe liver fatty infiltration carried a high risk of hypertension [odds ratio (OR):2.18,95% confidence interval (95% CI):1.27-3.75],dyslipidemia (OR:7.99,95% CI:4.34-14.73),impaired fasting glucose (OR:3.65,95% CI:1.04-12.85),and whole MS (OR:3.77;95% CI:1.90-7.47,P < 0.01).The state of insulin resistance (calculated by HOMA-IR and WBISI) deteriorated as the degree of fatty infiltration increased.CONCLUSION:NAFLD is not only a liver disease,but also an early mediator that reflects metabolic disorder,and liver B-ultrasound can be a useful tool for MS screening.

Autophagy in anti-apoptotic effect of augmenter of liver regeneration in HepG2 cells

AIM:To investigate the role of autophagy in the antiapoptotic effect of augmenter of liver regeneration(ALR).METHODS:Autophagy was induced through serum deprivation.An ALR-expressing plasmid was transfected into HepG2 cells,and autophagic flux was determined using fluorescence microscopy,electron microscopy,Western blot and quantitative polymerase chain reaction(q PCR) assays.After ALR-expressing plasmid transfection,an autophagy inhibitor [3-methyladenine(3-MA)] was added to HepG2 cells,and apoptosis was observed using fluorescence microscopy and flow cytometry.RESULTS:Autophagy was activated in HepG2 cells,peaking at 24 h after serum deprivation.Microtubuleassociated protein light chain three-II levels were higher in HepG2 cells treated with ALR than in control cells,fluorescence microscopy,electron microscopy and q PCR studies showed the similar trend,and p62 levels showed the opposite trend,which indicated that ALR may play an important role in increasing autophagy flux.The numbers of apoptotic cells were substantially higher in HepG2 cells treated with both ALR and 3-MA than in cells treated with ALR alone.Therefore,the protective effect of ALR was significantly attenuated or abolished when autophagy was inhibited,indicating that the anti-apoptotic effect of ALR may be related to autophagy.CONCLUSION:ALR protects cells from apoptosis partly through increased autophagy in HepG2 cells and may be valuable as a new therapeutic treatment for liver disease.

Construction of Gpm6a/ReelinGFPCreERT2 by BAC recombination using a specific gene in hepatic mesothelial or stellate cells

AIM To prepare a Gpm6a/Reelin^(GFPCreERT2) construct with a rapid and reliable strategy using a bacterial artificial chromosome(BAC). METHODS Gpm6 a and Reelin BACs were purified and transformed into SW102 E. coli by electroporation. The GFPCreE RT2 fragment was prepared from a shuttle vector and transformed into SW102 E. coli carrying a BAC. Homologous recombination was induced in SW102 E. coli. Recombinant clones were screened and confirmed by PCR and restriction enzyme digestion. Recombinant clones were transformed into SW102 E. coli to remove the kanamycin unit.RESULTS A complete BAC was successfully transformed into SW102 E. coli by electroporation because BAC purified from SW102 E. coli showed the same pattern as the original BAC with Bam H I digestion. The GFPCre ERT2 fragment was deemed to have been prepared successfully because we obtained the same size fragment as expected. Homologous recombination was induced, and GFPCre ERT2 was deemed to have been inserted into the correct site of the BAC because we found the band change was the same as the expected pattern after restriction enzyme digestion. The kanamycin unit was deemed to have been removed successfully because we obtained different sizes of bands that were consistent with the results expected by PCR with different primers. CONCLUSION The construct of Gpm6 a^(GFPCreERT2) or Reelin^(GFPCreERT2) was prepared successfully, which will establish a foundation for tracing the hepatic stellate cell lineage and studying its function.

Retraction Note: Construction of Gpm6a/ReelinGFPCreERT2 by BAC recombination using a specific gene in hepatic mesothelial or stellate cells

We have decided to retract the above article for further consideration due to some misunderstandings in communication.

Numerical and experimental study on the hydraulic characteristics of a vertical axial pump under various clearances of flare tube

In order to investigate the characteristics of a vertical axial flow pump under various clearances of flare tube, the bell-shaped inlet and box culvert outlet channels with flare tube are studied numerically and experimentally. Then, the cases of inlet and outlet channels with the least hydraulic loss are selected to form an integral pump system, for which both numerical simulation and experimental investigation are carried out. The numerical results agree well with the experimental data. It is shown that the clearances of the interfaces between different components of the pump system have a significant impact on the internal flow structure, turbulent entropy and hydraulic performance of the inlet and outlet channels. For the cases of normalized bottom clearance less than 0.5 and normalized top clearance larger than 0.4, the internal flow and hydraulic performance indexes of inlet and outlet channels are relatively poor. There also exists a critical clearance in either inlet or outlet channel at which the hydraulic loss reaches the maximum. The results serve as an important reference for the design as well as safe and efficient operation of the vertical axial flow pump system.