Sinusoidal Phase-Modulating Fabry-Perot Interferometer for Angular Displacement Measurement

In this paper, a sinusoidal phase-modulating Fabry-Perot interferometer is proposed to measure angular displacement. The usefulness of the interferometer is demonstrated by simulations and experiments.

Large-range displacement measurement using sinusoidal phase-modulating laser diode interferometer

A signal processing method of realizing a large-range displacement measurement in a sinusoidal phase- modulating laser diode interferometer is proposed. The method of obtaining the dynamic value of the effective sinusoidal phase-modulating depth is detailed, and the residual amplitude modulation is also taken into account. Numerical simulations and experiments are carried out to compare this method with the traditional one. We prove that, with this method, the sinusoidal phase-modulating laser diode interferometer can realize a centimeter-level displacement measurement range with high precision, which is much better than the traditional method.

Effects of Sinusoidal Vibration of Crystallization Roller on Composite Microstructure of Ti/Al Laminated Composites by Twin-Roll Casting

A new,innovative vibration cast-rolling technology of “electromagnetic stirring+dendrite breaking+asynchronous rolling” was proposed with the adoption of sinusoidal vibration of crystallization roller to prepare Ti/Al laminated composites,and the effect of sinusoidal vibration of crystallization roller on composite microstructure was investigated in detail.The results show that the metallurgical bonding of titanium and aluminum is realized by mesh interweaving and mosaic meshing,instead of transition bonding by forming metal compound layer.The meshing depth between titanium and aluminum layers (6.6μm) of cast-rolling materials with strong vibration of crystallization roller (amplitude 0.87 mm,vibration frequency 25 Hz) is doubled compared with that of traditional cast-rolling materials (3.1μm),and the composite interfacial strength(27.0 N/mm) is twice as high as that of traditional cast-rolling materials (14.9 N/mm).This is because with the action of high-speed superposition of strong tension along the rolling direction,strong pressure along the width direction and rolling force,the composite linearity evolves from "straight line" with traditional casting-rolling to "curved line",and the depth and number of cracks in the interface increases greatly compared with those with traditional cast-rolling,which leads to the deep expansion of the meshing area between interfacial layers and promotes the stable enhancement of composite quality.

Gadoxetic acid-enhanced magnetic resonance imaging in the assessment of hepatic sinusoidal obstruction syndrome in a mouse model

BACKGROUND Neoadjuvant chemotherapy can cause hepatic sinusoidal obstruction syndrome(SOS)in patients with colorectal cancer liver metastases and increases posto-perative morbidity and mortality.AIM To evaluate T1 mapping based on gadoxetic acid-enhanced magnetic resonance imaging(MRI)for diagnosis of hepatic SOS induced by monocrotaline.METHODS Twenty-four mice were divided into control(n=10)and experimental(n=14)groups.The experimental groups were injected with monocrotaline 2 or 6 days before MRI.MRI parameters were:T1 relaxation time before enhancement;T1 relaxation time 20 minutes after enhancement(T_(1post));a reduction in T1 relaxation time(△T_(1)%);and first enhancement slope percentage of the liver parenchyma(ESP).Albumin and bilirubin score was determined.Histological results served as a reference.Liver parenchyma samples from the control and experimental groups were analyzed by western blotting,and organic anion transporter polypeptide 1(OATP1)was measured.RESULTS T_(1post),△T_(1)%,and ESP of the liver parenchyma were significantly different between two groups(all P<0.001)and significantly correlated with the total histological score of hepatic SOS(r=-0.70,0.68 and 0.79;P<0.001).△T_(1)%and ESP were positively correlated with OATP1 levels(r=0.82,0.85;P<0.001),whereas T_(1post) had a negative correlation with OATP1 levels(r=-0.83;P<0.001).INTRODUCTION Hepatic sinusoidal obstruction syndrome(SOS)is also known as hepatic veno-occlusive disease of the liver[1].The main pathological feature of hepatic SOS is damage to liver terminal vessels,and the clinical symptoms of it include ascites and abdominal pain[2].It was first proposed in 1979 as an early complication of hematopoietic stem cell transplantation[3].The prevalence ranges from 5%to 60%,and hepatic SOS is a potentially severe complication and can even lead to death in severe cases[4].Recently,systemic neoadjuvant chemotherapy became widely regarded as one of the causes hepatic SOS in the patients with advanced metastatic colorectal cancer[5,6],especially those were treated with oxaliplatin[7,8].Oxaliplatin-based preoperative chemotherapy is used for patients with colorectal liver metastases as the standard regimen[8,9],because it could improve tumor resection outcome by shrinking the metastatic sites and reducing recurrence rate[10].Nevertheless,chemotherapy-induced hepatic SOS has been associated with a higher risk of postresection morbidity[11],such as intraoperative bleeding,intraoperative transfusions,and postoperative liver failure[12].Therefore,it is important to detect and diagnose of hepatic SOS timely.Currently,the gold standard is still based on liver biopsy[13],but it is an invasive procedure and has several limitations and complications,such as hemorrhage[14].A noninvasive diagnostic modality is needed for the assessment of hepatic SOS.Some noninvasive tools have been used for diagnosis of hepatic SOS.Researchers have utilized a preoperative platelet count and aspartate aminotransferase to platelet ratio index[15].In addition,some imaging methods such as shear wave ultrasonography,computed tomography,and gadoxetic acid-enhanced magnetic resonance imaging(MRI)have been promoted as useful methods for evaluation of hepatic SOS[16-18].Recent studies with monocrotaline(MCT)-treated rats were conducted to investigate diagnosis and prediction of severity of SOS.For example,intravoxel incoherent motion diffusion-weighted imaging,non-Gaussian diffusion models,and T1 rho quantification[19,20].The MCT-induced hepatic SOS animal model was reproducible,with a detailed pathological scoring criteria[21].Gadoxetic acid is a hepatocyte-specific contrast substance,which can provide parenchymal contrast in the hepato-biliary phase.It is reported that gadoxetic acid is absorbed into the liver parenchyma via organic anion transporter polypeptide 1(OATP1)on the hepatocyte membranes[22-24].Recently,several authors have described the feasibility of gadoxetic acid-enhanced MRI for the diagnosis of oxaliplatin-induced hepatic SOS[25].They mainly diagnosed hepatic SOS based on the signal intensity of the hepatobiliary specific phase.However,there were several limitations due to the inconsistency between signal intensity of the liver parenchyma and the concentration of contrast agent for evaluation of the degree of hepatic SOS[26].Therefore,we measured T1 relaxation time on parametric mapping because it is linearly related to the concentration of the contrast agent and is not affected by other factors[27].Yang et al[28]demonstrated T1 mapping on gadoxetic acid-enhanced MRI for the assessment of oxaliplatin-induced liver injury in a C57BL/6 mouse model.However,the main pathological changes in their model were hepatocyte degeneration and fibrosis.Therefore,we aimed to explore the effectiveness of T1 mapping based on gadoxetic acid-enhanced MRI for the diagnosis of hepatic SOS in a C57BL/6 mouse model,as well as a possible relation between OATP1 Levels and MRI parameters.

Pyrrolizidine alkaloids-induced hepatic sinusoidal obstruction syndrome: Pathogenesis, clinical manifestations, diagnosis,treatment, and outcomes

Hepatic sinusoidal obstruction syndrome (HSOS) can be caused by the intake of pyrrolizidine alkaloids (PAs). To date, PAs-induced HSOS has not been extensively studied. In view of the difference in etiology of HSOS between the West and China, clinical profiles, imaging findings, treatment, and outcomes of HSOS associated with hematopoietic stem cell transplantation or oxaliplatin might be hardly extrapolated to PAs-induced HSOS. Reactive metabolites derived from PAs form pyrrole-protein adducts that result in toxic destruction of hepatic sinusoidal endothelial cells. PAs-induced HSOS typically manifests as painful hepatomegaly, ascites, and jaundice. Laboratory tests revealed abnormal liver function tests were observed in most of the patients with PAs-induced HSOS. In addition, contrast computed tomography and magnetic resonance imaging scan show that patients with PAs-induced HSOS have distinct imaging features, which reveal that radiological imaging provides an effective noninvasive method for the diagnosis of PAs-induced HSOS. Liver biopsy and histological examination showed that PAs-induced HSOS displayed distinct features in acute and chronic stages. Therapeutic strategies for PAs-induced HSOS include rigorous fluid management, anticoagulant therapy, glucocorticoids, transjugular intrahepatic portosystemic shunt, liver transplantation, etc. The aim of this review is to describe the pathogenesis, clinical profiles, diagnostic criteria, treatment, and outcomes of PAs-induced HSOS.

Effects of ethanol on liver sinusoidal endothelial cells-fenestrae of rats

Important advances have been made in research into the mechanism of alcoholic liver disease (ALD) over the past few years,but the role of liver sinusoidal endothelial cell (LSEC) in ALD has not been elucidated adequately. This study was undertaken to investigate the effect of ethanol on fenestrae of LSECs in rats. METHODS: A rat model of alcoholic liver disease was established by means of direct intragastric instillation of ethanol. Fifty-five rats of experimental (35 rats) and control (20) groups were sacrificed at the end of 4,8,12 weeks respectively, and also at the end of 12-week abstinence. After heart perfusion, the liver tissue was fixed and stained with hematoxylin and eosin for observation of serial changes of LSEC-fenestrae under a transmission electron microscope. RESULTS: Normal LESC was flat with a nucleus and organelles arranged regularly. The distal cytoplasm displayed as a lamina with many fenestrae, lacking the basement membrane(BM) underneath the endothelium. At the end of 4-week alcohol feeding, the number of fenestrae decreased at the distal cytoplasm in some LSECs, without the formation of the BM underneath the endothelium. At the end of 8 weeks, the number of fenestrae decreased significantly or even disappeared. The BM began to develop incompletely underneath the endothelium, while the active fibroblast appeared. At the end of 12 weeks, the number of fenestrae decreased more significantly and the complete BM could even be seen. But the changes were mostly limited in the single or adjoining sinus, and fibrosis was scarcely formed. At the end of 12-week abstinence, defenestration and formation of the endothelial BM lightened significantly. CONCLUSIONS:Defenestration and formation of the BM in LSECs develop gradually with the chronic stimulation of ethanol. Hepatic sinusoidal capillarization and fibrosis will be seen if their state is more serious. These early changes, i. e., limited and regional defenestration and capillarization may be the basis of alcoholic peri-fibrosis. This kind of he- patic fibrosis is reversible after removal of etiological factors.

Reversible sinusoidal obstruction syndrome associated with tacrolimus following liver transplantation

Sinusoidal obstruction syndrome(SOS), previously known as hepatic veno-occlusive disease, is a rare disorder in solid organ transplant patients, and is an uncommon complication after liver transplantation. Severe SOS with hepatic failure causes considerable mortality. Tacrolimus has been reported to be an offending agent, which potentially plays a role in the pathophysiological process of SOS. SOS due to tacrolimus has been reported in lung and pancreatic transplantations, but has never been described in a liver transplant recipient. Herein, we present a case of SOS after liver transplantation, which was possibly related to tacrolimus. A 27-year-old man developed typical symptoms of SOS with painful hepatomegaly, ascites and jaundice after liver transplantation, which regressed following withdrawal of tacrolimus. By excluding other possible predisposing factors, we concluded that tacrolimus was the most likely cause of SOS.

Feedforward and Feedback Optimal Control for Linear Systems with Sinusoidal Disturbances

The linear systems affected by additive external sinusoidal disturbances is studied. The problem is to damp this forced oscillation in an optimal fashion. The main result of this paper is a new design approach is proposed of realizable feedforward and feedback optimal control law for a linear time invariant system with sinusoidal disturbances. The algorithm of solving the optimal control law is given. It is shown that the control law is easily realized and is robust with respect to errors produced by the external sinusoidal disturbances through simulation results.

Human hepatic sinusoidal endothelial cells can be distinguished by expression of phenotypic markers related to their specialised functions in vivo

The hepatic sinusoids are lined by a unique population of hepatic sinusoidal endothelial cells (HSEC), which is one of the first hepatic cell populations to come into contact with blood components. However, HSEC are not simply barrier cells that restrict the access of blood- borne compounds to the parenchyma. They are func- tionally specialised endothelial cells that have complex roles, including not only receptor-mediated clearance of endotoxin, bacteria and other compounds, but also the regulation of inflammation, leukocyte recruitment and host immune responses to pathogens. Thus understand- ing the differentiation and function of HSEC is critical for the elucidation of liver biology and pathophysiology. This article reviews methods for isolating and studying human hepatic endothelial cell populations using in vitro models. We also discuss the expression and functions of phe- notypic markers, such as the presence of fenestrations and expression of VAP-1, Stabilin-1, L-SIGN, which can be used to identify sinusoidal endothelium and to permit discrimination from vascular and lymphatic endothelial cells.

Pathological process of liver sinusoidal endothelial cells in liver diseases

Cirrhosis develops from liver fibrosis and is the severe pathological stage of all chronic liver injury. Cirrhosis caused by hepatitis B virus and hepatitis C virus infection is especially common. Liver fibrosis and cirrhosis involve excess production of extracellular matrix,which is closely related to liver sinusoidal endothelial cells(LSECs). Damaged LSECs can synthesize transforming growth factor-beta and platelet-derived growth factor,which activate hepatic stellate cells and facilitate the synthesis of extracellular matrix. Herein,we highlight the angiogenic cytokines of LSECs related to liver fibrosis and cirrhosis at different stages and focus on the formation and development of liver fibrosis and cirrhosis. Inhibition of LSEC angiogenesis and antiangiogenic therapy are described in detail. Targeting LSECs has high therapeutic potential for liver diseases. Further understanding of the mechanism of action will provide stronger evidence for the development of anti-LSEC drugs and new directions for diagnosis and treatment of liver diseases.

Adaptive ANFIS-based filter for active control of sinusoidal primary noise in nonlinear path

Linear active noise control (ANC) system is promising in suppressing broadband and narrowband noise in a linear acoustic site.However,in some situations,the acoustic systems are nonlinear which make the primary noise being nonlinear distortion at the canceling point,and the linear ANC system maybe can not work well for these cases.This paper presents an adaptive network-based fuzzy inference system (ANFIS)-based nonlinear filter for active noise control,which is expected to be successfully applied to situations with nonlinear distortion.In the proposed adaptive control algorithm,the parameters are updated by gradient descent method.In the simulations,the secondary-path FIR model coefficients are estimated in advance by off-line system identification method,and one case for sinusoidal primary noise with nonlinear distortion is presented,which verifies the effectiveness of the proposed system in suppressing sinusoidal noise generated by rotating machines,e.g.,engines in vehicles.

Liver stiffness and perfusion changes for hepatic sinusoidal obstruction syndrome in rabbit model

BACKGROUND Hepatic sinusoidal obstruction syndrome(SOS)is caused by damage to hepatic sinusoidal endothelial cells that results in fibrous obliteration of intrahepatic venules and necrosis of hepatocytes.Currently the diagnosis is primarily based on nonspecific clinical features and invasive liver biopsy.Therefore,noninvasive imaging methods are required for the early diagnosis and severity assessment of hepatic SOS.AIM To determine the effectiveness of supersonic shear wave imaging(SSI)and dual energy computed tomography(DECT)for diagnosing hepatic SOS using a rabbit model.METHODS Among nine New Zealand white rabbits(3-4 kg,male),three in control group ingested normal saline for 20 d and six in the SOS group ingested 6-thioguanine(5 mg/kg/d)for 20 d.Liver stiffness was measured using SSI on days 0,3,10,and 20.On the same days,liver perfusion was evaluated from virtual monochromatic images of 55 keV and iodine map using DECT.Morphologic changes in the liver were assessed using CT.Final pathology scores were compared between the two groups.Liver stiffness and perfusion parameters were compared according to the groups,days,and pathology scores.RESULTS Final pathology scores were significantly higher in the SOS than the control group(median 22 vs 2,P=0.024).No gross morphologic changes were seen in livers.Liver stiffness,Hounsfield Unit values,and iodine concentrations were higher in the SOS compared to the control group on days 10 and 20(all,P≤0.007).Compared to day 0,liver stiffness and perfusion parameters were higher on day 20 in the SOS group(all,P≤0.001).Correlation coefficients for liver stiffness(r=0.635),Hounsfield Unit values(r=0.587),and iodine concentration(r=0.611)with final pathology scores were positive without significance(all,P>0.05).CONCLUSION Liver stiffness and perfusion parameters were significantly increased in the livers of a rabbit SOS model.SSI and DECT might aid in early diagnosis of hepatic SOS.

Presence of disease specific autoantibodies against liver sinusoidal cells in primary biliary cirrhosis

AIM: To investigate the presence of autoantibodies directed against liver sinusoidal cells in primary biliary cirrhosis(PBC).METHODS: Liver biopsies from 21 PBC patients were studied and compared with 12 liver biopsies from disease controls [3 patients with hepatitis B(HBV) virus,3 patients with hepatitis C virus(HCV), 3 patients with non-alcoholic steatohepatitis and 3 patients with acute alcoholic hepatitis(AAH)]. As healthy controls, we used tissue specimens adjacent to metastatic liver adenocarcinoma. Normal serum was taken from staff members of the unit. The determination of the cell type targetedby autoantibodies present in the patients sera was performed by indirect immunofluorescence(IIF) analysis using paraffin-embedded liver sections as a substrate.Sera from homologous or heterologous PBC patients or sera from the disease control group were used as primary antibodies. The presence of autoantibodies was identified using confocal microscopy.RESULTS: In total, 18/21(85.7%) PBC patients exhibited positive staining in the sinusoidal cells, 10/21(47.6%) in lymphocytes, 8/21(38%) in cholangiocytes and 7/21(33.3%) in hepatocytes, when homologous serum and fluorescein isothiocyanate-conjugated immunoglobulin type G(IgG) secondary antibody were used. PBC sections incubated with heterologous PBC serum showed reduced staining(20% for sinusoidal cells, 20% for lymphocytes, 20% for cholangiocytes and 13.3% for hepatocytes). When IgM immunoglobulin, instead of IgG, was used as secondary antibody,positive staining was observed in 75% of lymphocytes,62.5% of cholangiocytes, 37.5% of hepatocytes and50% of the sinusoidal cells with a much stronger staining intensity. No staining was observed when either normal or PBC sera were used as a primary antibody on liver sections from the disease control group. When PBC sera were incubated with healthy control sections,weak positive staining of cholangiocytes was observed in 3/21(14.3%) PBC serum samples. Steatohepatitis serum on PBC sections gave a positive staining of some hepatocytes and lymphocytes but no staining on viral hepatitis sections. Incubation with HBV sera stained some hepatocytes, cholangiocytes and intra-sinusoidal or portal lymphocytes of PBC, HBV and AAH patients but not HCV patients.CONCLUSION: In this study, for the first time in diseased liver tissue, we have demonstrated that a large proportion of PBC patients have disease specific autoantibodies against liver sinusoidal cells.

Sinusoidal obstruction syndrome: A systematic review of etiologies,clinical symptoms, and magnetic resonance imaging features

BACKGROUND Sinusoidal obstruction syndrome (SOS) is a kind of rare liver disease which is characterized by damage to small hepatic vessels, affecting particularly the sinusoidal endothelium. Due to the special etiology and high mortality, early diagnosis of SOS is significant for clinical survival and prognosis. AIM To generalize the common etiologies and clinical symptoms of SOS and summarize the characteristic magnetic resonance imaging (MRI) features so as to provide more valuable information for early diagnosis of SOS. METHOD We searched PubMed, Web of science, Wanfang Data, China Knowledge Resource Integrated, VIP, and Cochrane Library databases without a limiting period and the types of articles. The search process mainly revolved around the etiologies, common clinical symptoms, and MRI imaging features of SOS. Ultimately, 29 full articles were included in this review and 222 articles were excluded. RESULTS Eleven case reports included 13 patients. The etiologies of these patients including chemotherapy (5/13), medicinal herbs containing pyrrolidine alkaloids (PAs, e.g. Tusanqi)(4/13), hematopoietic stem cell transplantation (HSCT)(2/13), drug toxicity (6-thioguanine)(1/13), and “poppers”, a recreational drug used during anal intercourse (1/13). Eighteen case series including 497 patients, and SOS in 465 (93.6%) patients was caused by PAs. Ascites, abdominal pain and swelling, jaundice were the most common clinical symptoms. Alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), gamma-glutamyl transpeptidase (GGT), total bilirubin (TBil), direct bilirubin (DBil), and prothrombin time (PT) had varying degrees of elevation.Heterogeneous signals on T1 weighted imaging/T2 weighted imaging (T1WI/T2WI), heterogeneous enhancement of liver parenchyma, ascites, hepatomegaly, narrowing and blurring of intrahepatic inferior vena cava and three main hepatic veins, edema around the portal vein, and gallbladder wall edema were the most common MRI imaging features of SOS. CONCLUSION In the West, SOS was mostly secondary to HSCT. Some SOS developed in the process of chemotherapy for hepatic metastatic tumor. A few SOS were caused by toxicity of certain drugs. In the East, Tusanqi was a major cause of SOS. Ascites, abdominal pain and swelling, jaundice were the common clinical symptoms. Elevations of ALT, AST, GGT, ALP, TBil, and DBil could be used as predictors of liver function damage. Numerous characteristic MRI imaging features could provide more valuable information for early diagnosis of SOS.

Vascular endothelial growth factor and angiopoietins regulate sinusoidal regeneration and remodeling after partial hepatectomy in rats

AIM： To study the regulatory mechanisms of sinusoida regeneration after partial hepatectomy. METHODS： We invesldgated the expression of angiopoietin （Ang）-1, Ang-2, Tie-2, and vascular endothelial growth factor （VEGF） in regenerating liver tissue by quantitative reverse-transcription polymerase chain reaction （RT- PCR） using a LightCycler （Roche Diagnostics） and also immunohistochemical staining after 70% hepatectomy in rats. In the next step, we isolated liver cells （hepatocytes, sinusoidal endothelial cell （SEC）, Kupffer cell, and hepatic stellate cells （HSC）） from regenerating liver tissue by in situ collagenase perfusion and counterflow elutriation, to determine potential cellular sources of these angiogenic factors after hepatectomy. Proliferation and apoptosis of SECs were also evaluated by proliferating cell nuclear antigen （PCNA） staining and the terminal deoxynucleotidyl transferase d-uridine triphosphate nick end labeling （TUNEL） assay, respectively. RESULTS： VEGF mRNA expression increased with a peak at 72 h after hepatectomy, decreasing thereafter. The expression of Ang-1 mRNA was present at detectable levels before hepatectomy and increased slowly with a peak at 96 h. Meanwhile, Ang-2 mRNA was hardly detected before hepatectomy, but was remarkably induced at 120 and 144 h. In isolated cells, VEGF mRNA expression was found mainly in the hepatocyte fraction. Meanwhile, mRNA for Ang-1 and Ang-2 was found in the SEC and HSC fractions, but was more prominent in the latter. The PCNA labeling index of SECs increased slowly, reaching a peak at 72 h, whereas apoptotic SECs were detected between 120 h and 144 h. CONCLUSION： Ang-Tie system, together with VEGF, plays a critical role in regulating balance between SEC proliferation and apoptosis during sinusoidal regeneration after hepatectomy. However, the VEGF system plays a more important role in the early phase of sinusoidal regeneration than angiopoietin/Tie system.

Is porto sinusoidal vascular disease to be actively searched in patients with portal vein thrombosis?

Porto sinusoidal vascular liver disease (PSVD) and portal vein thrombosis (PVT) are distinct vascular liver diseases characterized, respectively, by an intrahepatic and a prehepatic obstacle to the flow in the liver portal system. PVT may also occur as a complication of the natural history of PSVD, especially if a prothrombotic condition coexists. In other cases, it is associated to local and systemic pro-thrombotic conditions, even if its cause remains unknown in up to 25% despite an active search. In our opinion, the presence of PSVD should be suspected in patients with PVT especially in those with PVT “sine causa” and the active search of this condition should be included in their diagnostic work-out. However, sometimes the diagnosis of pre-existing PSVD is very hard. Biopsy cannot be fully discriminant as similar histological data have been described in both conditions. Liver stiffness may help as it has been shown to be higher in PSVD than in “pure” PVT, due to the presence of sclerosis in the portal venous radicles observable in PSVD patients. Nevertheless, comparing liver stiffness between PVT and PSVD has until now been restricted to very limited series of patients. In conclusion, even if it is still totally hypothetical, our point of view may have clinical consequences, especially when deciding to perform a liver biopsy in patients with a higher liver stiffness and suspending the anticoagulation in patients with PVT and no detectable prothrombotic factors.

Transjugular intrahepatic portosystemic shunt for pyrrolizidine alkaloid-related hepatic sinusoidal obstruction syndrome

BACKGROUND Treatments for hepatic sinusoidal obstruction syndrome(HSOS)are limited.AIM To evaluate transjugular intrahepatic portosystemic shunting(TIPS)as a treatment for pyrrolidine alkaloid-related HSOS(PA-HSOS).METHODS This retrospective analysis included patients with PA-HSOS admitted to the First Affiliated Hospital of the University of Science and Technology of China(June 2015 to January 2019).Baseline clinical characteristics and follow-up data were extracted from the medical records.All patients included in this study experienced failure of initial therapy.Patients were divided into the TIPS and conservative treatment groups according to the therapy they received.Liver function,maximal ascites depth,imaging characteristics,pathology findings,and survival were compared between groups.RESULTS The TIPS group included 37 patients(28 males),and the conservative treatment group included 17 patients(11 males).Baseline characteristics were similar between groups.There were two deaths in the TIPS group and seven deaths in the conservative treatment group during follow-up(3-48 mo).The 3-,6-,12-and 24-mo survival rates were 94.6%,94.6%,94.6%and 94.6%,respectively,in the TIPS group and 70.6%,57.8%,57.8%and 57.8%,respectively,in the conservative treatment group.Kaplan-Meier analysis revealed significantly longer survival for the TIPS group than for the conservative treatment group(P=0.001).Compared with the pre-treatment value,maximal ascites depth was significantly lower at 1 wk,2 wk,1 mo,and 3 mo for the TIPS group(all P<0.05)but not in the conservative treatment group.Contrast-enhanced computed tomography demonstrated the disappearance of patchy liver enhancement after TIPS.Pathology showed that liver congestion and hepatocyte swelling improved with time after TIPS placement.CONCLUSION TIPS may achieve better outcomes than conventional symptomatic treatment in patients with PA-HSOS.

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.

A Reaction-Diffusion Algorithm for Segmentation of Three-Dimensional Sinusoidal Networks in Rats Fed a High-Fat and High-Cholesterol Diet: New Insights and Evaluation

Microstructures in the liver are primarily composed of hepatocytes, hepatic blood, and biliary vessels. Because each hepatocyte comes in contact with both vessels, these vessels form three-dimensional (3D) periodic network patterns. Confocal microscope images are useful for observing 3D structures;however, it is necessary to explicitly describe the vessel structures using 3D images of sinusoidal endothelial cells. For this purpose, we propose a new approach for image segmentation based on the Turing reaction-diffusion model, in which temporal and spatial patterns are self-organized. Turing conditions provided reliable tools for describing the 3D structures. Moreover, using the proposed method, the sinusoidal patterns of rats fed a high-fat/high-cholesterol diet were examined;these rats exhibited pathological features similar to those of human patients with nonalcoholic steatohepatitis related to metabolic syndrome. The findings showed that the parameter in diffusion terms differed significantly among the experimental groups. This observation provided a heuristic argument for parameter selection leading to pattern recognition problems in diseased rats.

Effect of Micro-Dimples on Hydrodynamic Lubrication of Textured Sinusoidal Roughness Surfaces

Surface texturing has been applied to improving the tribological performance of mechanical components for many years. Currently, the researches simulate the film pressure distribution of textured rough surfaces on the basis of the average flow model, and however the influence of roughness on the film pressure distribution could not be precisely expressed. Therefore, in order to study the hydrodynamic lubrication of the rough textured surfaces, sinusoidal waves are employed to characterize untextured surfaces. A deterministic model for hydrodynamic lubrication of microdimple textured rough surfaces is developed to predict the distribution of hydrodynamic pressure. By supplementing with the JFO cavitation boundary, the load carrying capacity of the film produced by micro-dimples and roughness is obtained. And the geometric parameters of textured rough surface are optimized to obtain the maximum hydrodynamic lubrication by specifying an optimization goal of the load carrying capacity. The effect of roughness on the hydrodynamic pressure of surface texture is significant and the load carrying capacity decreases with the increase of the roughness ratio because the roughness greatly suppresses the hydrodynamic effect of dimples. It shows that the roughness ratio of surface may be as small as possible to suppress the effect of hydrodynamic lubrication. Additionally,there are the optimum values of the micro-dimple depth and area density to maximize the load carrying capacity for any given value of the roughness ratio. The proposed approach is capable of accurately reflects the influence of roughness on the hydrodynamic pressure, and developed a deterministic model to investigate the hydrodynamic lubrication of textured surfaces.