Risk factors for progression to acute-on-chronic liver failure during severe acute exacerbation of chronic hepatitis B virus infection

BACKGROUND Acute exacerbation in patients with chronic hepatitis B virus(HBV) infection results in different severities of liver injury. The risk factors related to progression to hepatic decompensation(HD) and acute-on-chronic liver failure(ACLF) in patients with severe acute exacerbation(SAE) of chronic HBV infection remain unknown.AIM To identify risk factors related to progression to HD and ACLF in compensated patients with SAE of chronic HBV infection.METHODS The baseline characteristics of 164 patients with SAE of chronic HBV infection were retrospectively reviewed. Independent risk factors associated with progression to HD and ACLF were identified. The predictive values of our previously established prediction model in patients with acute exacerbation(AE model) and the model for end-stage liver disease(MELD) score in predicting the development of ACLF were evaluated.RESULTS Among 164 patients with SAE, 83(50.6%) had compensated liver cirrhosis(LC),43 had progression to HD without ACLF, and 29 had progression to ACLF within 28 d after admission. Independent risk factors associated with progression to HD were LC and low alanine aminotransferase. Independent risk factors for progression to ACLF were LC, high MELD score, high aspartate aminotransferase(AST) levels, and low prothrombin activity(PTA). The area under the receiver operating characteristic of the AE model [0.844, 95%confidence interval(CI): 0.779-0.896] was significantly higher than that of MELD score(0.690, 95%CI: 0.613-0.760, P < 0.05) in predicting the development of ACLF.CONCLUSION In patients with SAE of chronic HBV infection, LC is an independent risk factor for progression to both HD and ACLF. High MELD score, high AST, and low PTA are associated with progression to ACLF. The AE model is a better predictor of ACLF development in patients with SAE than MELD score.

超声引导下腹横肌平面阻滞对于妇科腹腔镜手术患者预防性镇痛的效果

目的评价超声引导下腹横肌平面阻滞(TAPB)对于妇科腹腔镜手术患者预防性镇痛的效果。方法选取拟在全麻下行妇科腹腔镜手术患者60例,既往无其他特殊病史,美国麻醉医师协会(ASA)分级Ⅰ或Ⅱ级,年龄30~50岁,体重50~65 kg。采用随机数字表法,将其分为3组(n=20):对照组(Ⅰ组)、术前TAPB组(Ⅱ组)和术后TAPB组(Ⅲ组)。Ⅰ组不实施神经阻滞,Ⅱ组和Ⅲ组分别于麻醉诱导前或手术结束后行超声引导下双侧TAPB术。术后3组患者均采用1μg/ml舒芬太尼静脉自控镇痛(PCIA),背景输注速率2 ml/h,患者自控镇痛(PCA)剂量2 ml,锁定时间15 min,持续至术后第2天,维持疼痛视觉模拟(VAS)评分≤3分,若VAS评分>3分时,静脉注射氟比洛芬酯50 mg行镇痛补救。记录术后24 h内舒芬太尼单位时间内用量、镇痛补救情况和不良反应的发生情况,计算舒芬太尼节俭程度。结果与Ⅰ组比较,Ⅱ组和Ⅲ组术后24 h内舒芬太尼单位时间内用量、镇痛补救率和恶心呕吐的发生率降低(P<0.05);与Ⅲ组比较,Ⅱ组术后24 h内舒芬太尼单位时间内用量、镇痛补救率及恶心呕吐的发生率降低(P<0.05)。Ⅱ组较Ⅰ组舒芬太尼用量节俭35.0%,较Ⅲ组舒芬太尼用量节俭16.0%。结论超声引导下TAPB能为妇科腹腔镜手术患者提供良好的术后镇痛,术前行神经阻滞效果优于术后。

氢吗啡酮复合罗哌卡因用于胸腹腔镜联合食道癌根治术后硬膜外自控镇痛的效果观察

目的观察氢吗啡酮复合罗哌卡因用于胸腹腔镜联合食道癌根治术后硬膜外自控镇痛(PCEA)的效果及安全性。方法选择浙江省台州医院拟在全身麻醉复合硬膜外麻醉下行胸腹腔镜联合食道癌根治术的患者60例,随机分为氢吗啡酮复合罗哌卡因PCEA组(H组)和舒芬太尼复合罗哌卡因PCEA组(S组),每组各30例。H组:氢吗啡酮10μg/mL+罗哌卡因1.25 mg/mL;S组:舒芬太尼0.3μg/mL+罗哌卡因1.25 mg/mL。给药方案:负荷剂量为6 mL,维持剂量4 mL/h,自控剂量每次5 mL,锁时30 min。记录术后4、8、12、24和48 h静息和咳嗽时的视觉模拟评分(VAS)及下肢运动神经阻滞程度(改良Bromage分级)。记录术后48 h内PCEA的有效按压次数(D1)和实际按压次数(D2),并计算D1/D2,以评价镇痛满意度。记录术后48 h内不良反应发生情况和镇痛补救情况,并计算镇痛补救率。结果H组术后4、8、12、24和48 h静息和咳嗽时VAS评分明显较S组低(P<0.05)。H组术后48 h内PCEA的D1、D2和镇痛补救率明显低于S组(P<0.05),D1/D2和镇痛满意度明显高于S组(P<0.05)。两组患者术后4、8、12、24和48 h的改良Bromage分级和术后48 h内不良反应发生情况比较,差异均无统计学意义(P>0.05)。结论氢吗啡酮复合罗哌卡因用于胸腹腔镜联合食道癌根治术后,PCEA效果确切,不良反应少,且镇痛效果优于舒芬太尼复合罗哌卡因,患者满意度更高。

Effect of deep surface rolling on microstructure and properties of AZ91 magnesium alloy

A solution-treated AZ91 bulk material was deep-surface-rolled at room temperature to investigate the effect of deep surface rolling on the microstructure and mechanical properties of the alloy. Microhardness and microstructure along the depth of the treated surface layer were characterized. The results show that the affected layer was up to 2.0 mm thick and consisted of three sublayers: a severe deformation layer with thickness of about 400 μm from the topmost surface, a medium deformation layer with thickness of around 600 μm and a small deformation layer up to 1000 μm thick. In addition to grain refinement in the deformation layer, strain-induced precipitation of β phase (Mg17Al12) was observed, particularly in the severe and medium deformation layers. It is believed that the cooperative effects of grain refinement, strain hardening and precipitation strengthening led to the significant increase in hardness of the AZ91 alloy after the deep surface rolling.

^(125)I-labeled anti-b FGF monoclonal antibody inhibits growth of hepatocellular carcinoma

AIM: To investigate the inhibitory efficacy of 125I-labeled anti-basic fibroblast growth factor (bFGF) monoclonal antibody (mAb) in hepatocellular carcinoma (HCC).METHODS: bFGF mAb was prepared by using the 1G9B9 hybridoma cell line with hybridization technology and extracted from ascites fluid through a Protein G Sepharose affinity column. After labeling with 125I through the chloramine-T method, bFGF mAb was further purified by a Sephadex G-25 column. Gamma radiation counter GC-1200 detected radioactivity of 125I-bFGF mAb. The murine H22 HCC xenograft model was established and randomized to interventions with control (phosphate-buffered saline), 125I-bFGF mAb, 125I plus bFGF mAb, bFGF mAb, or 125I. The ratios of tumor inhibition were then calculated. Expression of bFGF, fibroblast growth factor receptor (FGFR), platelet-derived growth factor, and vascular endothelial growth factor (VEGF) mRNA was determined by quantitative reverse transcriptase real-time polymerase chain reaction.RESULTS: The purified bFGF mAb solution was 8.145 mg/mL with a titer of 1:2560000 and was stored at -20 °C. After coupling, 125I-bFGF mAb was used at a 1: 1280000 dilution, stored at 4 °C, and its specific radioactivity was 37 MBq/mg. The corresponding tumor weight in the control, 125I, bFGF mAb, 125I plus bFGF mAb, and 125I-bFGF mAb groups was 1.88 ± 0.25, 1.625 ± 0.21, 1.5 ± 0.18, 1.41 ± 0.16, and 0.98 ± 0.11 g, respectively. The tumor inhibition ratio in the 125I, bFGF mAb, 125I plus bFGF mAb, and 125I-bFGF mAb groups was 13.6%, 20.2%, 25.1%, and 47.9%, respectively. Growth of HCC xenografts was inhibited significantly more in the 125I-bFGF mAb group than in the other groups (P < 0.05). Expression of bFGF and FGFR mRNA in the 125I-bFGF mAb group was significantly decreased in comparison with other groups (P < 0.05). Groups under interventions revealed increased expression of VEGF mRNA (except for 125I group) compared with the control group.CONCLUSION: 125I-bFGF mAb inhibits growth of HCC xenografts. The coupling effect of 125I-bFGF mAb is more effective than the concomitant use of 125I and bFGF mAb.

Nano-Twinning and Martensitic Transformation Behaviors in 316L Austenitic Stainless Steel During Large Tensile Deformation

The evolutions of nano-twins and martensitic transformation in 316L austenitic stainless steel during large tensile deformation were studied by electron backscatter diffraction(EBSD)technology and transmission electron microscopy(TEM)in detail.The results show that due to the low stacking fault energy of the steel,phase transformation induced plasticity(TRIP)and twinning induced plasticity(TWIP)coexist during the tensile deformation.The deformation firstly induces the formation of deformation twins,and dislocation pile-up is caused by the reduction of the dislocation mean free path(MFP)or grain refinement due to the twin boundaries,which further induces the martensitic transformation.With the increase of tensile deformation,a large number of nano-twins andα’-martensite appear,and the width of nano-twins decreases gradually,meanwhile the frequency of the intersecting deformation twins increases.The martensitic transformation can be divided into two types:γ-austenite→α’-martensite andγ-austenite→ε-martensite.α’-martensite is mainly distributed near the twin boundaries,especially at the intersection of twins,whileε-martensite and stacking faults exist in the form of transition products between the twins and the matrix.

In Situ HRTEM Observation of Electron-Irradiation-Induced Amorphization and Dissolution of the E(Al_(18)Cr_2Mg_3) Phase in 7475 Al Alloy

Electron irradiation effects on phase stability of the E （Al18Cr2Mg3） phase have been investigated by high- angle annular dark-field scanning transmission electron microscopy and high-resolution transmission electron microscopy （HRTEM）. The in situ HRTEM observations show that the Ala8Cr2Mg3 particles with different thickness undergo amorphization and dissolution under 300 keV electron irradiation at 25 ℃. The results indicate that the intermetallic compound Al18Cr2Mg3 is unstable under electron irradiation, and structural changes mainly depend on the thickness of particles. Amorphization in the thick particles is caused by a combination of chemical disordering and an increase in point defect concentration. Dissolution after amorphization in the thin particles is attributed to the diffusion of point defect towards the Al matrix.

Finite element modeling of consolidation process of Si C fiber-reinforced titanium matrix composites via matrix-coated fiber method

The consolidation process of SiCf/Ti-6Al-4V composites by matrix-coated fiber (MCF) method via hot pressing was investigated using finite element modeling (FEM). By analyzing the elastic–plastic contact deformation of the representative aligned coated fibers, the consolidation maps delineating the time–temperature–pressure relationship for full densification were constructed. Both the flow coefficient and the contact area coefficient used to describe the contact deformation were calculated according to the model. In addition, the effect of fiber content on matrix stress distribution was analyzed. The results show that fiber content is a significant factor that influences the densification process. Higher fiber content will lower the consolidation rate.