Non-invasive evaluation of liver stiffness after splenectomy in rabbits with CCl_4-induced liver fibrosis

AIM To investigate the diagnostic performance of liver stiffness measurement(LSM) by elastography point quantification(Elast PQ) in animal models and determine the longitudinal changes in liver stiffness by Elast PQ after splenectomy at different stages of fibrosis.METHODS Liver stiffness was measured in sixty-eight rabbits with CCl4-induced liver fibrosis at different stages and eight healthy control rabbits by Elast PQ. Liver biopsies and blood samples were obtained at scheduled time points to assess liver function and degree of fibrosis. Thirty-one rabbits with complete data that underwent splenectomy at different stages of liver fibrosis were then included for dynamic monitoring of changes in liver stiffness by Elast PQ and liver function according to blood tests.RESULTS LSM by Elast PQ was significantly correlated with histologic fibrosis stage(r = 0.85, P 0.001). The optimal cutoff values by Elast PQ were 11.27, 14.89, and 18.21 k Pa for predicting minimal fibrosis, moderate fibrosis, and cirrhosis, respectively. Longitudinalmonitoring of the changes in liver stiffness by Elast PQ showed that early splenectomy(especially F1) may delay liver fibrosis progression.CONCLUSION Elast PQ is an available, convenient, objective and non-invasive technique for assessing liver stiffness in rabbits with CCl4-induced liver fibrosis. In addition, liver stiffness measurements using Elast PQ can dynamically monitor the changes in liver stiffness in rabbit models, and in patients, after splenectomy.     

Staging of liver fibrosis or cirrhosis: The role of hepatic venous pressure gradient measurement

Liver fibrosis is a common histological change of chronic liver injury and it is closely related with portalhypertension which is hemodynamic complication of chronic liver disease. Currently, liver fibrosis has been known as a reversible dynamic process in previous literatures. Although liver biopsy is a gold standard for assessing the stage of liver fibrosis, it may not completely represent the stage of liver fibrosis because of sampling error or semi-quantative measurement. Recent evidences suggested that histologic, clinical, hemodynamic, and biologic features are closely associated in patients with chronic liver disease. Hepatic venous pressure gradient(HVPG) measurement has been known as a modality to evaluate the portal pressure. The HVPG measurement has been used clinically for fibrosis diagnosis, risk stratification, preoperative screening for liver resection, monitoring the efficacy of medical treatments, and assessing the prognosis of liver fibrosis. Therefore, the HVPG measurement can be used to monitor areas the chronic liver disease but also other important areas of chronic liver disease.     

Contrast-enhanced ultrasonography for the evaluation of liver fibrosis after biliary obstruction

AIM:To investigate perfusion change in contrastenhanced ultrasonography(CEUS) to evaluate liver fibrosis based on biliary obstruction using an animal model.METHODS:New Zealand white rabbits(3-4 kg) underwent bile duct ligation to form a biliary obstruction model.We performed liver CEUS and laboratory tests on the day before the operation(day 0) and every 7 postoperative days until the rabbits were sacrificed.After CEUS,signal intensity of liver parenchyma with a time-intensity curve was analyzed.Perfusion parameters were automatically calculated from regionof-interests,including peak signal intensity,mean transit time,area under the curve and time to peak.Histological grades of liver fibrosis were assessed according to the Metavir score system immediately after sacrifice.Generalized estimating equations were used to analyze the association between liver fibrosis grades and perfusion parameters for statistical analysis.The perfusion parameters were measured on the last day and the difference between day 0 and the last day were evaluated.RESULTS:From the nine rabbits,histological grades of liver fibrosis were grade 1 in one rabbit,grade 2 and 3 in three rabbits each,and grade 4 in two rabbits.Among the four CEUS parameters,only the peak signal intensity measured on the last day demonstrated a significant association with liver fibrosis grades(OR =1.392,95%CI:1.114-1.741,P =0.004).The difference in peak signal intensity between day 0 and the last dayalso demonstrated an association with liver fibrosis(OR =1.191,95%CI:0.999-1.419,P =0.051).The other parameters tested,including mean transit time,area under the curve,and time to peak,showed no significant correlation with liver fibrosis grades.CONCLUSION:This animal study demonstrates that CEUS can be used to evaluate liver fibrosis from biliary obstruction using peak signal intensity as a parameter.     

CT perfusion at early stage of hepatic diffuse disease

AIM: To determine the validity of the non-invasive method of CT perfusion (CTP) in rat model of hepatic diffuse disease. METHODS: Twenty-eight Wistar rats were divided into two groups. Liver diffuse lesions were induced by diethyln-itrosamine in 14 rats of test group. Rats in control group were bred with pure water. From the 1st to 12th wk after the test group was intervened, both groups were studied every week with CTP. CTP parameters of liver parenchyma in different periods and pathologic changes in two groups were compared and analyzed. RESULTS: The process of hepatic diffuse lesions in test groups was classified into three stages or periods according to the pathologic alterations, namely hepatitis, hepatic fibrosis, and cirrhosis. During this period, hepatic artery flow (HAF) of control group declined slightly, mean transit time (MTT), blood flow (BF) and volume (BV) increased, but there were no significant differences between different periods. In test group, HAF tended to increase gradually, MTT prolonged obviously, BV and BF decreased at the same time. The results of statistical analysis revealed that the difference in the HAF ratio of test group to control group was significant. The ratio of BV and BF in test group to control group in stage of hepatitis and hepatic cirrhosis, hepatic fibrosis and early stage of hepatic cirrhosis was significantly different, but there was no significant difference between hepatitis and hepatic fibrosis. The main pathological changes in stage of hepatitis were swelling of hepatic cells, while sinusoid capillarization and deposition of collagen aggravated gradually in the extravascular Disse's spaces in stage of fibrosis and early stage of cirrhosis. CONCLUSION: The technique could reflect some early changes of hepatic blood perfusion in rat with liver diffuse disease and is valuable for their early diagnosis.     

肝星状细胞活化相关信号通路在肝纤维化中的研究进展

肝纤维化是多种慢性肝损伤造成的细胞外基质(extracellular matrix, ECM)过度累积及降解不足的病理结果,如不加以干预会逐渐进展为肝硬化,甚至肝细胞癌。肝星状细胞(hepatic stellate cell, HSC)是ECM的主要来源,并且HSC在肝纤维化的起始、发展和消退过程中发挥关键作用。近年来,HSC活化涉及的信号传导通路成为研究热点,本文总结了HSC活化过程中的重要信号通路。     

Liver analysis using gadolinium‐ethoxybenzyl‐diethylenetriamine pentaacetic acid‐enhanced magnetic resonance imaging: Correlation with histological grading and quantitative liver evaluation prior to hepatectomy

Aim: To examine the effectiveness of gadolinium‐ethoxybenzyl‐diethylenetriamine pentaacetic acid (Gd‐EOB‐DTPA)‐enhanced magnetic resonance imaging (MRI) in the assessment of parenchymal liver fibrosis and quantitative liver function prior to hepatectomy. Methods: Between July 2008 and September 2011, the data of 93 consecutive patients undergoing preoperative Gd‐EOB‐DTPA‐enhanced MRI were analyzed, including serum fibrosis marker levels (hyaluronic acid, type IV collagen), 15‐min retention rates of indocyanine green (ICG‐R15) in the ICG clearance test, and technetium‐99m galactosyl serum albumin scintigraphy results. Liver intensity values were obtained by calculating the differences between the intensity of the liver and that of other organs in the hepatobiliary phase. Degrees of liver fibrosis were quantitatively assessed (F0–4). MRI data were correlated with the prospectively acquired clinical data. Results: Varying degrees of liver fibrosis were detected in 31 of the 93 patients. The intensity ratio of the liver to spinal cord on MRI negatively correlated with hepatic fibrosis (R = ?0.479, P < 0.001) and ICG‐R15 (R = ?0.492, P < 0.001). When patients with F0–2 (normal/moderate) and F3–4 (severe) liver fibrosis were compared, the intensity ratio of the enhanced liver to spinal cord (IRLS) on MRI was significantly lower in the F3–4 group than in the F0–2 group. IRLS was correlated with liver fibrosis, and, when an IRLS criterion of less than 1.702 was used, severe liver fibrosis could be predicted with 68.8% sensitivity and 93.5% specificity. Conclusion: Preoperative Gd‐EOB‐DTPA‐enhanced MRI analysis can detect quantitative indicators of liver fibrosis and function, thus aiding the assessment of hepatic remnants prior to hepatectomy.     

Arguments against toxic effects of chemotherapy on liver injury and regeneration in an experimental model of partial hepatectomy

Background: New chemotherapy regimens are increasingly used in metastatic colorectal cancer to the liver before surgery. Some clinical observations have suggested that chemotherapy may affect liver regeneration. Aims: The aim of this study was to evaluate liver damage and liver regeneration after chemotherapy treatment in a model of partial hepatectomy. Methods: C57BL/6 mice were repeatedly treated with intraperitoneal injections of either saline or different chemotherapy regimens including the drugs 5‐fluorouracyl (5‐FU), irinotecan, oxaliplatin, gemcitabine and combined treatments with 5‐FU/irinotecan, 5‐FU/oxaliplatin. A 70% partial hepatectomy was performed 1 week after the last injection. Ki‐67 and PCNA immunohistochemistry were performed to assess liver regeneration, serum liver enzymes and histology analysis to evaluate injury. Results: A variety of chemotherapeutic agents used at maximum tolerated doses compatible with survival affected body weight and blood cell levels. However, these regimens did not affect liver injury before and after hepatectomy nor did they impair liver regeneration. Liver histology showed no steatosis, fibrosis or inflammation before hepatectomy. We therefore tested whether chemotherapy in presence of diet‐induced steatosis may trigger injury. Even under these conditions, we did not observe histological signs of inflammation or sinusoidal injury. Conclusions: Liver injury and liver regeneration are not impaired after neoadjuvant chemotherapy with 5‐FU, irinotecan, oxaliplatin and gemcitabine in non‐tumoural liver parenchyma. In addition, combined treatments disclose no adverse effects on liver regeneration. Chemotherapy alone induces no histological alterations even in the presence of steatosis.     

肝纤维化无创诊断研究进展

慢性肝脏疾病是一个全球性的重大公共健康问题,肝纤维化是疾病发展中关键病理阶段之一,其分期及程度对肝病的治疗和预后起决定性作用。近年来,随着新型无创诊断方法的不断涌现,其在很大程度上取代了肝穿刺活检来评估慢性肝病的严重程度。这些方法大致可分为以下两类:基于血清生物标志物的"生物学"方法和基于弹性成像技术的"物理学"方法。本文将对常见肝病中肝纤维化的无创诊断方法的相关研究进展进行简要综述。     

Liver angioscintigraphy: clinical applications

Liver angioscintigraphy (LAS) is a radio-isotope method for the investigation of liver perfusion and its alteration in various hepatic diseases. It measures the arterial and portal venous fractions of total liver blood flow. The percentage of liver blood flow supplied by hepatic artery is estimated mathematically by the hepatic perfusion index (HPI), normally between 25 % and 40 %. The decrease of portal blood flow in liver cirrhosis is compensated ("buffer" mechanisms) by increased arterial supply, with higher HPI value. For a patient with chronic liver disease, HPI over 50% suggests arterialization of hepatic perfusion, guiding the diagnose to liver cirrhosis. Splenic curve is completing the diagnostic information of the hepatic curve. Corroborated with per rectal scintigraphy and liver SPECT, LAS offers a good hemodynamic staging of chronic inflammatory liver diseases. Malignant tumors (primitive or metastases) increase the arterial supply of the liver and decrease the portal flow, HPI being over 50% (currently 65 % - 90 %). Benign tumors do not change portal/arterial liver blood flow ratio. SPECT or non-scintigraphic morphological investigations increase the diagnostic value of LAS for primitive liver tumors. Liver cancer occurring on cirrhosis is a limitative factor for LAS. Hepatic metastases increase the arterial perfusion (and HPI value) very quickly, before their size allows morphologic imaging diagnosis. LAS is therefore an early method to diagnose liver metastases being especially used in colorectal cancer. Other clinical applications of LAS are: follow up of liver toxicity of drugs, evaluation of portal vein permeability, post surgery follow up of the liver tumor patients.     

Mechanistic insights of rapid liver regeneration after associating liver partition and portal vein ligation for stage hepatectomy

AIM To highlight the potential mechanisms of regeneration in the Associating Liver Partition and Portal vein ligation for Stage hepatectomy models(clinical and experimental) that could unlock the myth behind the extraordinary capability of the liver for regeneration,which would help in designing new therapeutic options for the regenerative drive in difficult setup,such as chronic liver diseases. Associating Liver Partition and Portal vein ligation for Stage hepatectomy has been recently advocated to induce rapid future liver remnant hypertrophy that significantly shortens the time for the second stage hepatectomy. The introduction of Associating Liver Partition and Portal vein ligation for Stage hepatectomy in the surgical armamentarium of therapeutic tools for liver surgeons represented a real breakthrough in the history of liver surgery. METHODS A comprehensive literature review of Associating Liver Partition and Portal vein ligation for Stage hepatectomy and its utility in liver regeneration is performed. RESULTS Liver regeneration after Associating Liver Partition and Portal vein ligation for Stage hepatectomy is a combination of portal flow changes and parenchymal transection that generate a systematic response inducing hepatocyte proliferation and remodeling. CONCLUSION Associating Liver Partition and Portal vein ligation for Stage hepatectomy represents a real breakthrough in the history of liver surgery because it offers rapid liver regeneration potential that facilitate resection of liver tumors that were previously though unresectable. The jury is still out though in terms of safety,efficacy and oncological outcomes. As far as Associating Liver Partition and Portal vein ligation for Stage hepatectomy-induced liver regeneration is concerned,further research on the field should focus on the role of nonparenchymal cells in liver regeneration as well as on the effect of Associating Liver Partition and Portal vein ligation for Stage hepatectomy in liver regeneration in the setup of parenchymal liver disease.     

Liver fibrosis markers in alcoholic liver disease

Alcohol is one of the main factors of liver damage. The evaluation of the degree of liver fibrosis is of great value for therapeutic decision making in patients with alcoholic liver disease (ALD). Staging of liver fibrosis is essential to define prognosis and management of the disease. Liver biopsy is a gold standard as it has high sensitivity and specificity in fibrosis diagnostics. Taking into account the limitations of liver biopsy, there is an exigency to introduce non-invasive serum markers for fibrosis that would be able to replace liver biopsy. Ideal serum markers should be specific for the liver, easy to perform and independent to inflammation and fibrosis in other organs. Serum markers of hepatic fibrosis are divided into direct and indirect. Indirect markers reflect alterations in hepatic function, direct markers reflect extracellular matrix turnover. These markers should correlate with dynamic changes in fibrogenesis and fibrosis resolution. The assessment of the degree of liver fibrosis in alcoholic liver disease has diagnostic and prognostic implications, therefore noninvasive assessment of fibrosis remains important. There are only a few studies evaluating the diagnostic and prognostic values of noninvasive biomarkers of fibrosis in patients with ALD. Several noninvasive laboratory tests have been used to assess liver fibrosis in patients with alcoholic liver disease, including the hyaluronic acid, FibroTest, FibrometerA, Hepascore, Forns and APRI indexes, FIB4, an algorithm combining Prothrombin index (PI), α-2 macroglobulin and hyaluronic acid. Among these tests, Fibrotest, FibrometerA and Hepascore demonstrated excellent diagnostic accuracy in identifying advanced fibrosis and cirrhosis, and additionally, Fibrotest was independently associated with survival. Therefore, the use of biomarkers may reduce the need for liver biopsy and permit an earlier treatment of alcoholic patients.     

The utility of two-dimensional shear wave elastography and texture analysis for monitoring liver fibrosis in rat model

Background:Liver fibrosis is a common pathological change caused by a variety of etiologies.Early diagnosis and timely treatment can reverse or delay disease progression and improve the prognosis.This study aimed to assess the potential utility of two-dimensional shear wave elastography and texture analysis in dynamic monitoring of the progression of liver fibrosis in rat model.Methods:Twenty rats were divided into control group(n = 4) and experimental groups(n = 4 per group) with carbon tetrachloride administration for 2,3,4,and 6 weeks.The liver stiffness measurement was performed by two-dimensional shear wave elastography,while the optimal texture analysis subsets to distinguish fibrosis stage were generated by Ma Zda.The results of elastography and texture analysis were validated through comparing with histopathology.Results:Liver stiffness measurement was 6.09 ± 0.31 k Pa in the control group and 7.10 ± 0.41 k Pa,7.80 ± 0.93 k Pa,8.64 ± 0.93 k Pa,9.91 ± 1.13 k Pa in the carbon tetrachloride induced groups for 2,3,4,6 weeks,respectively(P 0.05).By texture analysis,histogram and co-occurrence matrix had the most frequency texture parameters in staging liver fibrosis.Receiver operating characteristic curve of liver elasticity showed that the sensitivity and specificity were 95.0% and 92.5% to discriminate liver fibrosis and non-fibrosis,respectively.In texture analysis,five optimal parameters were selected to classify liver fibrosis and non-fibrosis.Conclusions:Two-dimensional shear wave elastography showed potential applications for noninvasive monitoring of the progression of hepatic fibrosis,even in mild fibrosis.Texture analysis can further extract and quantify the texture features in ultrasonic image,which was a supplementary to further visual information and acquired high diagnostic accuracy for severe fibrosis.     

Opportunistic infections in the liver of HIV-infected patients in Thailand: a necropsy study.

Liver necropsy from patients infected with human immunodeficiency virus was analyzed in 117 cases. Wide ranges of opportunistic infections were recorded in 47%. Cryptococcosis (21.4%) was the most outstanding infection, followed by tuberculosis (16.2%), cytomegalovirus (5.1%) and penicillosis (3.4%). Non-specific alterations of the liver tissues included fatty steatosis (49.6%), fibrosis (55.6%), portal inflammation and reactive hepatitis. Cases of chronic active and chronic passive hepatitis and one case of hepatocellular carcinoma were reported. In the infected liver, predominant pathological changes included granuloma and spotty necrosis, which were attributed to tuberculous hepatitis. Infection with Cryptococcus usually showed no associated pathological change. The sensitivity for the clinical diagnosis of Cryptococcus was 88.8% and specificity was 91.7%. For tuberculosis, sensitivity was 20% and specificity was 67.9%.     

Liver regeneration and restoration of liver function after partial hepatectomy: the relation of fibrosis of the liver parenchyma

BACKGROUND/AIMS: Patients who survive partial hepatectomy sometimes have unsatisfactory liver regeneration and restoration of liver function. Although the extent of resection should be adjusted to attain favorable liver regeneration and restoration of liver function, a guiding principle for this has not been established. METHODOLOGY: Seventy patients with hepatic tumors associated with liver disorders of various severity who underwent hepatectomy were studied. We calculated the removal rate of the liver and the regeneration rate of the remnant liver using computed tomography. The liver function was investigated using ICG R-15 (retention rate of indocyanine green). Liver disorder was classified into 4 groups, according to the severity of fibrosis. RESULTS: The regeneration rates of the remnant liver indicated a significant decline in patients with severe fibrosis. In the no fibrosis and mild fibrosis groups, an increased removal rate was associated with increased regeneration rate, and post-operative ICG R-15 improved with time. However, in the moderate fibrosis and severe fibrosis groups, an increased removal rate was not associated with increased regeneration rate, and post-operative ICG R-15 showed no change or became worse with time. CONCLUSIONS: Severe fibrosis of the liver parenchyma is associated with poorer regeneration of the remnant liver leading to poor restoration of post-operative liver function. The severity of fibrosis is useful as a predictive factor for liver regeneration and restoration of liver function after partial hepatectomy.     

Hepatobiliary manifestations of critically ill and postoperative patients

Liver dysfunction is common in both the critically ill and postoperative patient. Metabolic derangements secondary to sepsis, poor hepatic perfusion, total parenteral nutrition, in addition to hemodynamic and anesthetic-induced changes that occur during surgery, can cause liver damage ranging from small self-limited abnormalities in liver chemistries to acute liver failure. Early recognition, supportive care, and effective treatment of the underlying disease process are crucial steps in managing liver disease in a critically ill patient.     

肝纤维化血清学诊断研究进展

肝纤维化是由各种慢性肝病引起细胞外基质在肝脏过度沉积所致,可进展为肝硬化并导致肝功能衰竭和门静脉高压等。肝纤维化具有可逆性已成为共识。因此,准确诊断和评估肝纤维化程度对肝纤维化的防治及其预后评估具有非常重要的意义。肝纤维化诊断的金标准是肝脏活检,但由于其具有创伤性、费用昂贵而难以被患者接受。血清学检查是诊断肝纤维化较为理想的检测方法,可对肝纤维化进行早期诊断,并可进行动态观察。由多个血清学指标组成的非创伤性诊断模型,提高了肝纤维化的诊断准确性。本文就肝纤维化的血清学诊断研究进展进行综述。     

Effect of liver inflammation on accuracy of FibroScan device in assessing liver fibrosis stage in patients with chronic hepatitis B virus infection

BACKGROUND Transient elastography(FibroScan)is a new and non-invasive test,which has been widely recommended by the guidelines of chronic hepatitis B virus(HBV)management for assessing hepatic fibrosis staging.However,some confounders may affect the diagnostic accuracy of the FibroScan device in fibrosis staging.AIM To evaluate the diagnostic value of the FibroScan device and the effect of hepatic inflammation on the accuracy of FibroScan in assessing the stage of liver fibrosis in patients with HBV infection.METHODS The data of 416 patients with chronic HBV infection who accepted FibroScan,liver biopsy,clinical,and biological examination were collected from two hospitals retrospectively.Receiver operating characteristic(ROC)curves were used to analyze the diagnostic performance of FibroScan for assessing the stage of liver fibrosis.Any discordance in fibrosis staging by FibroScan and pathological scores was statistically analyzed.Logistic regression and ROC analyses were used to analyze the accuracy of FibroScan in assessing the stage of fibrosis in patients with different degrees of liver inflammation.A non-invasive model was constructed to predict the risk of misdiagnosis of fibrosis stage using FibroScan.RESULTS In the overall cohort,the optimal diagnostic values of liver stiffness measurement(LSM)using FibroScan for significant fibrosis(≥F2),severe fibrosis(≥F3),and cirrhosis(F4)were 7.3 kPa[area under the curve(AUC)=0.863],9.7 kPa(AUC=0.911),and 11.3 kPa(AUC=0.918),respectively.The rate of misdiagnosis of fibrosis stage using FibroScan was 34.1%(142/416 patients).The group of patients who showed discordance between fibrosis staging using FibroScan and pathological scores had significantly higher alanine aminotransferase and aspartate aminotransferase levels,and a higher proportion of moderate to severe hepatic inflammation,compared with the group of patients who showed concordance in fibrosis staging between the two methods.Liver inflammation activity over 2(OR=3.53)was an independent risk factor for misdiagnosis of fibrosis stage using FibroScan.Patients with liver inflammation activity≥2 showed higher LSM values using FibroScan and higher rates of misdiagnosis of fibrosis stage,whereas the diagnostic performance of FibroScan for different fibrosis stages was significantly lower than that in patients with inflammation activity<2(all P<0.05).A non-invasive prediction model was established to assess the risk of misdiagnosis of fibrosis stage using FibroScan,and the AUC was 0.701.CONCLUSION Liver inflammation was an independent risk factor affecting the diagnostic accuracy of FibroScan for fibrosis stage.A combination of other related noninvasive factors can predict the risk of misdiagnosis of fibrosis staging using FibroScan.     

Assessment of hemodynamics in precancerous lesion of hepatocellular carcinoma： Evaluation with MR perfusion

AIM: To investigate the hemodynamic changes in a precancerous lesion model of hepatocellular carcinoma (HCC). METHODS: Hemodynamic changes in 18 Wistar rats were studied with non-invasive magnetic resonance (MR) perfusion. The changes induced by diethylnitrosamine (DEN) developed into liver nodular lesions due to hepatic cirrhosis during the progression of carcinogenesis. The MR perfusion data [positive enhancement integral (PEI)] were compared between the nodular lesions corresponding well with MR images and pathology and their surrounding hepatic parenchyma. RESULTS: A total of 46 nodules were located by MR imaging and autopsy, including 22 dysplastic nodules (DN), 9 regenerative nodules (RN), 10 early HCCs and 5 overt HCCs. Among the 22 DNs, 6 were low-grade DN (lGDN) and 16 were high-grade DN (HGDN). The average PEI of RN, DN, early and overt HCC was 205.67 ± 31.17, 161.94 ± 20.74, 226.09 ± 34.83, 491.86 ± 44.61 respectively, and their liver parenchyma nearby was 204.84 ± 70.19. Comparison of the blood perfusion index between each RN and its surrounding hepatic parenchyma showed no statistically significant difference (P = 0.06). There were significant differences in DN (P = 0.02). During the late hepatic arterial phase, the perfusion curve in DN declined. DN had an iso-signal intensity at the early hepatic arterial phase and a low signal intensity at the portal venous phase. Of the 10early HCCs, 4 demonstrated less blood perfusion and 6 displayed minimally increased blood flow compared to the surrounding parenchyma. Five HCCs showed significantly increased blood supply compared to the surrounding parenchyma (P = 0.02). CONCLUSION: Non-invasive MR perfusion can detect changes in blood supply of precancerous lesions.     

Post-hepatectomy regeneration of the murine liver I. Effect upon Schistosoma mansoni lesions, before and after chemotherapy

Hepatic histopathological changes due to Schistosoma mansoni infection in the mouse presented considerable improvement following partial hepatectomy, both during early (acute) and late (chronic) infections, and especially when surgery was preceded by curative chemotherapy. A 60% hepatectomy removed a great deal of a diseased liver that was replaced by a normal-looking tissue in which schistosomal lesions appeared fewer and scattered. After chemotherapy, residual fibrosis left either from cured acute and chronic schistosomal lesions, almost completely disappeared when the regenerated liver was examined a month afterwards. These marked changes, brought about by hepatectomy in experimental hepatic schistosomiasis, illustrate the fact that post-hepatectomy regeneration tends to restore the normal structure of the liver, even in a diseased organ.     

基质金属蛋白酶-9与肝纤维化关系的研究进展

肝纤维化是由于基质金属蛋白酶(matrix metalloproteinases,MMPs)及其组织抑制因子(tissue inhibitor of metalloproteinasas,TIMPs)比例失调,造成细胞外基质大量沉积在细胞间质中,引起的病理改变。目前研究发现MMP-9在肝纤维化形成过程中有诱发和促进作用,但也有一些相反的意见,认为其具有逆转肝纤维化的作用,与肝纤维化呈负相关。因此,本文就近年来对MMP-9功能的研究作一概述。