大麦总多酚不同溶剂提取物对DPPH自由基清除能力的影响

酚类化合物是大麦中主要的抗氧化物质之一,直接影响到麦芽、麦汁和啤酒的品质.研究了体积分数100%的甲醇、体积分数8O%的甲醇、体积分数8O%的乙醇、体积分数8O%的丙酮和水等5种不同提取溶剂对大麦游离多酚和结合多酚提取率的影响,以及不同溶剂提取物清除DPPH自由基能力的差异.结果表明:提取溶剂对大麦多酚的提取效率有显著影响,不同溶剂提取物清除DPPH自由基的能力有显著性差异;其中以80%丙酮溶液为提取溶剂时,所得提取物的游离多酚质量分数及其对DPPH自由基清除率最高,可作为大麦抗氧化物质的提取溶剂;不同品种大麦间游离总多酚质量分数及其对DPPH自由基清除率存在显著差异;结合Folin-Ciocaheu法和DPPH自由基清除率法分剐测定大麦总多酚质量分数和抗氧化力,可初步评价大麦原料的抗氧化特性.＃     

白芷活性提取物清除自由基与抗氧化作用

研究了香辛料白芷中活性物的提取工艺,试验结果表明:以体积分数75%乙醇为溶剂,白芷粉碎度为20目,固液比保持1 g∶10 mL,回流萃取1h,提取2次,能有效提取出白芷中活性成分.用邻苯三酚自氧化法和亚硝基R盐-Co3+褪色法对白芷提取物进行了自由基清除、抗氧化性能的研究.发现白芷提取物能有效清除自由基,当质量浓度为1.0×10-3g/mL时,提取物对过氧阴离子自由基(O2-·)和羟基自由基(·OH)的清除率分别为23.40%和69.35%,可作为一种性能良好的新型天然清除自由基、抗氧化剂,应用于食品和药品中.     

泰和乌骨鸡黑色素的体外抗氧化作用

采用分光光度法测定磷钼酸配合物、自由基和丙二醛(MDA)的含量,用于研究酶法提取的泰和乌骨鸡黑色素的总抗氧化能力及其清除自由基和抗脂质过氧化的作用,研究过程中用合成黑色素与之进行比较.结果表明:泰和乌骨鸡黑色素清除羟基自由基的能力虽然低于合成黑色素,但其总抗氧化能力与合成黑色素相当,而清除DPPH自由基和超氧阴离子自由基的能力以及抗脂质过氧化作用都优于合成黑色素,说明泰和乌骨鸡黑色素具有明显的体外抗氧化功能.     

羟化赖氨酸清除活性氧自由基能力的研究

在竹叶及其提取物中检出了一种特殊的非蛋白氨基酸δ－ＯＨ－Ｌｙｓ，为了解其生物学意义，用化学发光法和电子自旋共振法（ＥＳＲ）对δ－ＯＨ－Ｌｙｓ和Ｌｙｓ清除超氧阴离子自由基（Ｏ２－）的能力作了比较，结果表明赖氨酸在δ位羟化以后，抗活性氧自由基的活性有了显著提高。     

花生衣红抗氧化活性的研究

花生衣是花生产品的副产物,经济价值低,但是含有大量的多酚物质.作者研究了从花生衣中提取的红色素对超氧阴离子(O2-.)、羟自由基(OH.)的清除作用及其对脂质过氧化物的阻抑作用.实验结果表明,花生衣红色素对超氧阴离子(O2-.)、羟自由基(OH.)有不同程度的清除作用,对脂质过氧化有明显的抑制,且呈剂量依赖关系.     

用化学发光法研究黄酮化合物对O_2~－·和·OH的清除

在对化学发光法的产生体系进行改良的基础上，研究了黄酮化合物对超氧阴离子及羟基自由基的清除作用，结果表明黄酮化合物的结构同自由基的清除作用密切相关，对自由基的清除机理可能是作为氢供体以及稳定基中间体而阻断自由基的链式反应。     

绿茶提取物茶多酚在化妆品中的抗氧化效果研究

目的:探讨绿茶提取物茶多酚在化妆品中的抗氧化效果。方法:选取皮肤衰老患者70例,随机分为两组,观察组和对照组,每组各35例,观察组患者使用含绿茶提取物的护肤品,对照组采取空白基质,连续使用2个月,对两组患者皮肤抗氧化效果,使用前后面部衰老症状评分以及不良反应发生情况进行比较。体外评价采取Vit C阳性对照法,测定其清除DPPH自由基,羟自由基和超氧阴离子的能力。结果:以维生素C(Vit C)为阳性对照,绿茶提取物具有较好清除DPPH自由基、羟基自由基及超氧阴离子的能力;经过使用该乳膏后,观察组患者的总有效率明显高于对照组,差异具有统计学意义(P0.05);对于患者的症状改善情况进行评分,观察组与对照组治疗后评分与治疗前相比较均有所降低,差异均具有统计学意义(P0.05),而观察组患者评分改善程度明显高于对照组,差异具有统计学意义(P0.05)。无明显不良反应。结论:绿茶提取物在化妆品中具有良好的抗氧化作用,其可以与体内自由基结合转变为惰性的物质,阻止了体内自由基反应,对皮肤衰老有良好的治疗效果,而且其为天然提取物,安全性高,可以在化妆品制备中进行广泛使用。     

以几种药食植物为基质的灵芝发酵和体外清除自由基活性的研究

药用真菌灵芝对7种中药进行发酵，结果表明银杏叶、桑叶、竹叶在添加0．7g／dL时对灵芝的生长有抑制作用，生物量分别为：0．6347、0．6903、0．7960g／dL,干姜、薏苡仁、枸杞、苦养对灵芝的生长有促进作用分别为：1．0509、1．0437、1．0708、L0538g／dL。在清除自由基的效果上，添加苦荞、桑叶、枸杞后灵芝对清除两种自由基的效果不如灵芝本身的效果，清除羟自由基的抑制率分别为：68．2％、66．6％、68．5％；清除超氧阴离子的抑制率分别为：26．9％、31．9％、35％；添加银杏叶、薏苡仁、生姜后灵芝对两种自由基的作用效果都有提高，清除羟自由基的抑制率分别为70．5％、75％、70．6％；清除超氧阴离子的抑制率为34．9、38％、33％。     

六月霜中提取物清除O2.-和OH.自由基

应用氮蓝四唑 (NBT)光还原法 ,对六月霜中提取物清除超氧离子自由基O2 ·- 的效果进行了测定 .结果显示 ,六月霜提取物对超氧离子自由基有较强的清除效果 ,清除效果与提取物中黄酮质量浓度有关 ,当黄酮质量浓度达到一定值时 ,对O2 ·- 的清除效果可高达 88.4 1% .提取物与抗坏血酸 (Vc)进行了对照实验 ,结果显示其对O2 ·- 的清除能力比Vc高 .六月霜提取物在Vc—Cu2 —H2 O2 体系中 ,对OH·自由基的清除效果的研究显示 ,最高清除率为 84 .0 2 % .     

葡-半乳低聚糖体外抗氧化活性研究

作者研究了高、中、低3种不同聚合度葡-半乳低聚糖在DPPH体系和羟自由基体系中清除自由基的能力.结果表明:高聚合度葡-半乳低聚糖对DPPH自由基的清除能力较中、低聚合度葡-半乳低聚糖强,IC50为13 mg·mL-1;而对·OH的清除能力,中聚合度葡-半乳低聚糖较强,其IC50为21 mg·mL-1.高、中聚合度的葡-半乳低聚糖在两种体系中均有较好的清除作用,聚合度大小影响葡-半乳低聚糖清除自由基的活性.     

Acid-base equilibrium and vascular exclusion of the liver: study of 30 extensive hepatectomies

The acid-base disorders after hepatic vascular exclusion (HVE) were studied in 30 major liver resections. HVE included portal triad clamping and occlusion of the inferior vena cava below and above the liver, without venous shunt nor cooling. Clamping of the supra-coeliac abdominal aorta (AoC) was associated with HVE in 12 patients. HVE lasted 18 to 65 min (mean 37 min). Liver ischemia and splanchnic blood pooling resulted in metabolic acidosis and hyperlactatemia. In order to prevent his acidosis, prophylactic administration of NaHCO23 was used during the first 19 cases. This induced significant metabolic alkalosis during HVE and the early postoperative period; increasing experience made us reduce the amount of NaHCO3. After the release of the clamps, Paco2 increased 25% following HVE without AoC (p less than 0.001) and 53% following HVE with AoC (p less than 0.001). In an attempt to distinguish between the effects of the metabolic acidosis and the rise of Paco2 in the fall of pH which occurred after removal of the clamps, NAaHCO3 was deliberately not given in the last 11 patients. Acidosis appeared to be greater with AoC than without and mainly related to the rise of Paco2. A fall of Paco2 to its initial value was always followed by the return of pH to the normal range. This study demonstrated the human ability to correct spontaneously the acidosis which followed HVE. The need for NaHCO3 after HVE reflected a poor hemodynamic state after major liver resection rather than a metabolic consequence of hepatic ischaemia.     

肝静脉阻断技术在近第二肝门巨大肝血管瘤切除术中的应用

目的 探讨肝静脉肝外阻断在近第二肝门肝脏巨大血管瘤切除术中的应用.方法 回顾分析2003年1月至2009年12月施行19例近第二肝门肝脏巨大血管瘤切除术患者的临床资料.分为肝静脉阻断(hepatic vein exclusion,HVE)组(9例)与下腔静脉阻断(inferior vena cava exclusion,IVE)组(10例),记录患者术中出血量、输血量、术后肝功能恢复情况和术后2 d平均腹腔引流量和并发症发生率等指标.结果 两组患者年龄、性别和瘤体大小的差异均无统计学意义;HVE组中未发生切肝前肝静脉分离过程中损伤;9例肝血管瘤均采用血管瘤体剥除术顺利切除,IVE组1例行右半肝切除;HVE组术中出血及输血量分别为(220±121)ml和(44±88)ml,明显少于IVE组(945±978)ml和(560±717)ml(P＜0.05);HVE组5例切除肝脏血管瘤过程中出现肝静脉损伤未发生大出血,而IVE组4例肝静脉损伤2例术中大出血;术后第1天丙氨酸转氨酶,术后第3天总胆红素HVE组均低于IVE组;术后2 d平均引流量HVE组明显少于IVE组;治疗总费用HVE组低于IVE组.结论 应用肝静脉阻断技术可以增加近第二肝门巨大血管瘤手术切除的安全性,减少治疗费用.

Abstract：

Objective To evaluate hepatic vein exclusion (HVE) outside the liver in the resection of giant hepatic hemangioma near the second hepatic hilum. Methods From January 2003 to December 2009, giant hepatic hemangiomas near the second hepatic hilum were resected in 19 cases. Preoperatively 19 cases were divided into two groups: HVE group (9 cases) and IVE group ( 10 cases). Data regarding the intra-operative and postoperative courses of the patients were analyzed. Results There was no difference between the 2 groups regarding the age, sex and tumor size. No damage of hepatic vein was happened in HVE group. Resection of the hemangioma was applied in all cases of HVE group, and 1 case in IVE group had right hemi-hepatectomy. Hepatic veins rupture occurred in 4 cases in IVE group and 2 cases of them had massive bleeding, while in HVE group hepatic veins rupture occurred in 5 cases but no massive bleeding occurred. Intra-operative blood loss was significantly less in HVE group than IVE group. The serum ALT value in postoperative day 1 and total bilirubin in postoperative day 3 in HVE group was significantly lower than that of the IVE group. The mean drainage volume in HVE group was significantly less than that of the IVE group on postoperative day 1 and day 2. The total cost of patient in HVE group were significant less than in IVE group. Conclusions The use of hepatic vein exclusion reduces the risk in the resection of giant hepatic hemangioma near the second hepatic hilum.     

Hepatic vascular exclusion as a model for complete and stable hepatic ischemia in dogs.

In order to confirm a complete ischemia model, 1-hour warm hepatic ischemia by hepatic vascular exclusion (HVE) was studied in dogs, in comparison with that by inflow occlusion (IOC) only. The splanchnic venous bed and/or infrahepatic inferior vena cava were decompressed by a centripetal pump-driven venovenous bypass. Indocyanine green retention test revealed no hepatic blood flow in the HVE model during ischemia, while hepatic blood perfusion was still present in the IOC model. All 5 of the IOC dogs survived more than 7 days after revascularization, while 4 of the 5 HVE dogs died within 9 h. After the induction of hepatic ischemia, lactate increased in both HVE and IOC dogs. After revascularization, transaminases and guanase were elevated, the arterial ketone body ratio (acetoacetate/3-hydroxybutyrate) decreased and the serum lactate accumulated more in HVE dogs than in IOC dogs. The hepatic redox state of IOC dogs was significantly decreased by additional clamping of the inferior vena cava. It is concluded that the HVE model with a pump-driven active bypass provides complete and stable hepatic ischemia, resulting in greater deterioration of hepatic cellular functions; hence it is more suitable as a model of complete hepatic ischemia than the IOC one.     

肝脏巨大血管瘤行肝静脉与下腔静脉阻断的临床效果分析

目的探讨肝静脉肝外阻断在近第二肝门肝脏巨大血管瘤治疗中的应用。方法回顾性分析2012年2月至2014年5月收治的32例肝门肝脏巨大血管瘤患者的临床资料,根据治疗方法分为肝静脉阻断(HVE组14例)与下腔静脉阻断(IVE组18例)。记录两组患者术中情况、术后情况及并发症情况差异。在SPSS 10.0中进行统计分析,术中指标;术后第1、3、7天的生化指标以(x珋±s)表示,采用两样本独立t检验,两组间并发症率比较采用卡方检验,检验水准取α=0.05。结果 HVE组的手术时间、术中出血量、输血量、术后引流量均显著的低于IVE组(t=3.005、t=8.187、t=17.411、t=6.958,P0.05)。IVE组的总胆红素(TBIL)在术后3 d显著高于HVE组(t=3.024,P=0.012);IVE组的ALT、AST在术后第1天显著高于HVE组(t=2.673、t=2.801、P0.05)差异均有统计学意义。术后并发症HVE组为2例(14.29%)显著低于IVE组的9例(50.00%)(χ2=4.453,P=0.035)。结论相对于IVE技术,HVE技术的术中创伤更小,术后肝功能恢复更快,并发症发生率更低。     

Portal triad clamping or hepatic vascular exclusion for major liver resection. A controlled study.

OBJECTIVE: The authors compared operative course of patients undergoing major liver resections under portal triad clamping (PTC) or under hepatic vascular exclusion (HVE). SUMMARY BACKGROUND DATA: Reduced blood loss during liver resection is achieved by PTC or HVE. Specific complications and postoperative hepatocellular injury mediated with two procedures have not been compared. METHODS: Fifty-two noncirrhotic patients undergoing major liver resections were included in a prospective randomized study comparing both the intraoperative and postoperative courses under PTC (n = 24) or under HVE (n = 28). RESULTS: The two groups were similar at entry, but eight patients were crossed over to the other group during resection. In the HVE group, hemodynamic intolerance occurred in four (14%) patients. In the PTC group, pedicular clamping was not efficient in four patients, including three with involvement of the cavohepatic intersection and one with persistent bleeding due to tricuspid insufficiency. Intraoperative blood losses and postoperative enzyme level reflecting hepatocellular injury were similar in the two groups. Mean operative duration and mean clampage duration were significantly increased after HVE. Postoperative abdominal collections and pulmonary complications were 2.5-fold higher after HVE but without statistical significance, whereas the mean length of postoperative hospital stay was longer after HVE. CONCLUSIONS: This study shows that both methods of vascular occlusion are equally effective in reducing blood loss in major liver resections. The HVE is associated with unpredictable hemodynamic intolerance, increased postoperative complications with a longer hospital stay, and should be restricted to lesions involving the cavo-hepatic intersection.     

Preoperative hepatic venous embolization for partial hepatectomy combined with segmental resection of major hepatic vein

BACKGROUND: Liver resection of segments VII and/or VIII sometimes requires segmental resection of the right hepatic vein in patients with liver tumours invading or located close to the hepatic vein. In this situation, hepatic vein reconstruction is thought to have an important role in the postoperative function of segment VI. This study investigated whether preoperative embolization of the major hepatic vein could obviate the need for hepatic vein reconstruction after cranial partial resection of the liver including the major hepatic vein trunk in a preclinical model. METHODS: Sixteen beagles were divided into two groups of eight: control group (hepatectomy alone) and hepatic venous embolization (HVE) group (hepatectomy after HVE). HVE was performed 2 weeks before hepatectomy. All dogs underwent resection of the cranial third of the left lateral liver lobe together with the major trunk of the left hepatic vein. Following hepatectomy, survival, histological features, portal venous pressure and serum aspartate aminotransferase (AST) levels were determined. RESULTS: Six control animals and seven in the HVE group were alive 1 week after hepatectomy. Immediately after hepatectomy, portal venous pressure was significantly higher in the control group compared with the HVE group (mean(s.d.) 14.0(1.1) versus 8.1(1.0) mmHg; P < 0.01). Histological examination of the remnant left lateral lobe demonstrated patchy parenchymal haemorrhage in the control group and normal parenchymal architecture in the HVE group. Peak AST levels were observed on day 1 in both groups and were significantly higher in the control group (mean(s.d.) 182(42) versus 67(40) units/l; P < 0.01). CONCLUSION: In this model, preoperative HVE facilitated interlobar venous collateral formation and minimized the untoward effects of segmental hepatic vein resection. This procedure may obviate the need for hepatic vein reconstruction after cranial partial liver resection including the major hepatic vein.     

肝静脉-门静脉联合栓塞术促进预留肝脏快速增生——结直肠癌肝转移转化切除新策略

目的 评价肝静脉-门静脉联合栓塞术（HVE+PVE）安全性、促进预留肝脏增生的能力及联合系统治疗用于初始不可切除结直肠癌肝转移（CRLM）转化切除的可行性。方法 回顾性分析2020年12月至2021年11月复旦大学附属中山医院3例肝左、右叶多发初始不可切除CRLM病例经系统治疗后,病灶缩小,但剩余肝体积（FLR）不足,行HVE+PVE后转化切除的临床资料。结果 HVE+PVE后平均18.6 d,FLR从平均423.6 mL增生至561 mL,平均增长率32.8%;剩余肝体积（FLR）/标准肝体积（SLV）从平均33.5%增至43.8%,无并发症发生。HVE+PVE后平均23 d行右半肝+左肝部分切除术等,平均出血333.3 mL,未输血。术后无Clavien-Dindo Ⅲ级以上并发症,无肝功能衰竭及90 d死亡。均获得R0切除。平均11.3 d出院。结论 HVE+PVE通过介入操作即可使FLR快速增生,具有操作简捷、创伤小、安全等优点。联合系统治疗可以增加初始不可切除CRLM的转化切除率。     

Hemodynamic and hormonal responses to the sudden interruption of caval flow: insights from a prospective study of hepatic vascular exclusion during major liver resections

Hepatic vascular exclusion (HVE) combines portal triad clamping and occlusion of the inferior vena cava. Although HVE has been performed for major liver resections during the last 2 decades, little is known about the mechanisms that explain its satisfactory hemodynamic tolerance. Consequently, we performed a comprehensive study of both hemodynamic and hormone responses to HVE. Twenty-two patients who underwent liver resection for secondary tumors developed in noncirrhotic livers were prospectively studied. Heart rate, arterial blood pressure, pulmonary artery pressure, mixed venous saturation, cardiac output, and left ventricular dimensions determined by transesophageal echocardiography were monitored in HVE patients. Blood concentrations of arginine vasopressin (AVP), epinephrine, norepinephrine, dopamine, and atrial natriuretic peptide and plasma renin activity (PRA) were measured before clamping; 5, 15, and 30 min after clamping; and 15 min after unclamping. Hemodynamic response to HVE was characterized by a significant (P < 0.05) decrease in left ventricular dimensions, fractional area change, and pulmonary artery pressure. We also observed a marked decrease in cardiac output (50%) and an increase in heart rate and systemic vascular resistance. After unclamping, there was peripheral vasodilation, assessed by a significant decrease in systemic vascular resistance from the preclamping value to unclamping. An acute and sustained increase in AVP and norepinephrine that returned to baseline after unclamping and the absence of modification in PRA concentrations were noted. The marked decrease in venous return that characterizes HVE is compensated for by an increase in vascular resistance secondary to an important activation of the AVP and sympathetic systems. The PRA system does not play an important role in maintaining arterial blood pressure during HVE. IMPLICATIONS: Hemodynamic and hormonal responses to the acute interruption of caval venous return to the heart were investigated in patients undergoing liver resection with hepatic vascular exclusion. A compensatory role for arginine vasopressin and sympathetic systems that provoked increased vascular resistance was demonstrated.     

Systemic and regional effects of supraceliac aortic occlusion during experimental hepatic vascular exclusion

BACKGROUND: Supraceliac aortic occlusion (AO) has been recommended to avoid hypotension during hepatic vascular exclusion (HVE). We hypothesized that AO may negatively affect splanchnic perfusion during HVE. METHODS: Twenty-six dogs (16 +/- 0.3 kg) were randomly assigned to HVE (n = 13) or HVE+AO (n = 13), during 30 minutes followed by a 60-minute reperfusion period. Cardiac output (CO), mean arterial pressure (MAP), superior mesenteric artery blood flow (SMABF, ultrasonic flowprobe), gastric mucosal PCO(2) (gas tonometry) and PCO(2)-gap were evaluated. RESULTS: HVE alone induced decreases in MAP from 115 +/- 5.1 to 26 +/- 1 mm Hg, in CO from 2.0 +/- 0.1 to 0.4 +/- 0.1 L/min and SMABF from 398 +/- 42 to 16 +/- 7.6 mL/min, while PCO(2) gap increased from 4 +/- 3.7 to 52 +/- 5.4 mm Hg. Supraceliac aortic occlusion only avoided severe hypotension. During reperfusion MAP, CO, and SMABF were partially restored, while PCO(2) gap showed no improvements in either group. CONCLUSIONS: HVE promotes major systemic and splanchnic perfusional derangement. Concomitant AO may avoid HVE-induced hypotension without producing further deleterious effects.     

Vascular exclusion technique in liver resection for hepatocellular carcinoma

An overview of the vascular exclusion technique in liver resection is presented. The technical aspects of hepatic vascular exclusion (HVE) are described along with the hemodynamic monitoring requirements. The hepatic tolerance to normothermic liver ischemia of 60-min duration is quite good in the absence of underlying chronic liver disease such as cirrhosis or steatosis. However, our recent experience with cirrhotic patients has demonstrated that vascular clamping may be well tolerated even after major liver resection if normothermic liver ischemia is limited (33 min for HVE, 55 min for Pringle maneuver). The main advantages of HVE are: reduction of operative blood loss, increased resectability rate of HCC when the tumor is close or invades the hepatic veins and/or the vena cava, and better safety during the performance of the most hazardous liver resections.