Ultrasound (US) is often the first imaging modality employed in patients with suspected focal liver lesions. The role of US in the characterisation of focal liver lesions has been transformed with the introduction of ...Ultrasound (US) is often the first imaging modality employed in patients with suspected focal liver lesions. The role of US in the characterisation of focal liver lesions has been transformed with the introduction of specific contrast media and the development of specialized imaging techniques. Ultrasound now can fully characterise the enhancement pattern of hepatic lesions, similar to that achieved with contrast enhanced multiphasic computed tomography (CT) and magnetic resonance imaging (MRI). US contrast agents are safe, well-tolerated and have very few contraindications. Furthermore, real-time evaluation of the vascularity of focal liver lesions has become possible with the use of the newer microbubble contrast agents. This article reviews the enhancement pattern of the most frequent liver lesions seen, using the second generation US contrast media. The common pitfalls for each type of lesion are discussed. The recent developments in US contrast media and specific imaging techniques have been a major advance and this technique, in view of the intrinsic advantages of US, will undoubtedly gain popularity in the years to come.展开更多
AIM: To investigate the pharmacological effects of rice flavone (5,4'-dihydroxy-3',5'-dimethoxy-7-0-β-D-glucopyranosyloxy-flavone, RF) separated from panicle-differentiating to flowing rice on rat experim...AIM: To investigate the pharmacological effects of rice flavone (5,4'-dihydroxy-3',5'-dimethoxy-7-0-β-D-glucopyranosyloxy-flavone, RF) separated from panicle-differentiating to flowing rice on rat experimental hepatic injury. METHODS: Models of rat acute hepatic injury induced by carbon tetrachloride (CCl4) administration, rat hepatic fibrosis induced by thioacetamide, injury of primary cultured rat hepatocytes induced by CCl4, respectively, were established. After treated with RF, content of serum alanine transaminase (ALT), aspartate aminotransferase (AST) and albumin (Alb), hyaluronic acid (HA), the activity of glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), and hydroxyproline (Hyp) were measured and liver tissue was observed pathologically by hematoxylin-eosin (HE) staining. Effects of RF on pathological changes, function index, enzyme of scavenging free radicals and blood rheology were evaluated. RESULTS: In model of rat acute hepatic injury induced by CCI4, RF can significantly decrease the contents of serum ALT, AST, increase the content of Alb, improve the dropsy and fat denaturalization of hepatocytes. In model of rat hepatic fibrosis induced by thioacetamide, RF can inhibit the increase of HA, Hyp and whole blood viscosity, and improve the activities of GSH-Px and SOD, and inauricular microcirculation. CONCLUSION: RF has apparent protective effects on hepatic injury by increasing activity of GSH-Px and SOD, scavenging free radicals produced by CCI4, reducing blood viscosity, and improving microcirculation and blood supply.展开更多
AIM:This study investigated the mechanisms of protection afforded by the proton pump inhibitor lansoprazole against gastric injury induced by different non-steroidal anti-inflammatory drugs (NSAIDs) in rats. METHODS: ...AIM:This study investigated the mechanisms of protection afforded by the proton pump inhibitor lansoprazole against gastric injury induced by different non-steroidal anti-inflammatory drugs (NSAIDs) in rats. METHODS: Male Sprague-Dawley rats were orally treated with indomethacin (100 μmol/kg), diclofenac (60 μmol/kg), piroxicam (150 μmol/kg) or ketoprofen (150 μmol/kg). Thirty minutes before NSAIDs, animals were orally treated with lansoprazole 18 or 90 umol/kg. Four hours after the end of treatments, the following parameters were assessed: gastric mucosal PGE2, malondialdehyde (MDA), myeloperoxidase (MPO) or non-proteic sulfhydryl compounds (GSH) levels; reverse transcription-polymerase chain reaction (RT-PCR) of mucosal COX-2 mRNA; gastric acid secretion in pylorus-ligated animals; in vitro effects of lansoprazole (1-300 μmol/L) on the oxidation of low density lipoproteins (LDLs) induced by copper sulphate. RESULTS: All NSAIDs elicited mucosal necrotic lesions which were associated with neutrophil infiltration and reduction of PGE2 levels. Increments of MPO and MDA contents, as well as a decrease in GSH levels were detected in the gastric mucosa of indomethacin- or piroxicam-treated animals. Indomethacin enhanced mucosal cyclooxygenase-2 expression, while not affecting cyclooxygenase-1. At the oral dose of 18 μmol/kg lansoprazole partly counteracted diclofenac-induced mucosal damage, whereas at 90 μmol/kg it markedly prevented injuries evoked by all test NSAIDs. Lansoprazole at 90 μmol/kg reversed also the effects of NSAIDs on MPO, MDA and GSH mucosal contents, without interfering with the decrease in PGE2 levels or indomethacin-induced cyclooxygenase-2 expression. However, both lansoprazole doses markedly inhibited acid secretion in pylorus-ligated rats. Lansoprazole concentration-dependently reduced the oxidation of LDLs in vitro. CONCLUSION: These results suggest that, besides the inhibition of acid secretion, lansoprazole protection against NSAID-induced gastric damage depends on a reduction in mucosal oxidative injury, which is also responsible for an increment of sulfhydryl radical bioavailability. It is also suggested that lansoprazole does not influence the down-regulation of gastric prostaglandin production associated with NSAID treatment.展开更多
To investigate the relation between material＇s cychc plastic behaviour and fatigue crack growth, a new model is proposed. The model incorporated the two intrinsic properties of material＇ s cyclic plastic and crack ...To investigate the relation between material＇s cychc plastic behaviour and fatigue crack growth, a new model is proposed. The model incorporated the two intrinsic properties of material＇ s cyclic plastic and crack tip＇ s deformation dislocation to interpret fatigue crack threshold. The relation between material＇ s cyclic hardening parameters （cyclic hardening amplitude and cyclic hardening rate） and fatigue threshold is studied. Fatigue threshold is determined based on the dislocation-free zone （DFZ） model, the theory of cohesive zone and the cyclic deformation behaviour. The results show that fatigue threshold increases with the decrease of the amplitude of cyclic hardening and is independent of cyclic hardening rate, but fatigue crack growth rate increases with the increase of cyclic hardening rate.展开更多
To examine the effect of multi-glycoside of Tripterygium wilfordii Hook. f. （GTW） on proteinuria and acute glomerular immune lesion in experimental mesangial proliferative glomerulonephritis （MsPGN） induced by ant...To examine the effect of multi-glycoside of Tripterygium wilfordii Hook. f. （GTW） on proteinuria and acute glomerular immune lesion in experimental mesangial proliferative glomerulonephritis （MsPGN） induced by anti-Thyl. 1 monoelonal antibody （mAb） 1-22-3. The reversible model of MsPGN with anti-Thyl. 1 mAb 1-22-3 was established. After 7 days of oral treatment with GTW （ 100 mg/kg per day） and vehicle （distilled water, 5 ml/kg per day）, its effects on proteinuria, renal functions, mesangial morphological change, glomerular macrophage accumulation, and mRNA expressions of cytokines （PDGF-BB and MCP-1 ） were evaluated by light microscope （LM）, immunofluorescence （IF）, and reverse transcription polymerase chain reaction （RT-PCR）. It was found that GTW ameliorated proteinuria （on day 3 and day 7）, mesangial proliferation （total cell number, matrix expansion, a-smooth muscle actin expression, and collagen type Ⅰ expression） and macrophage accumulation （ED3^＋ ） in experimental MsPGN. In addition, GTW significantly suppressed the increased mRNA expressions for MCP-1 （67.6% to eontrol group, P 〈 0.01） together with the tendency to reduce the expression of PDGF （24.44% to control group） on day 7. It is concluded that GTW can not only decrease proteinuria, but also ameliorate acute mesangial alterations and glomerular activated macrophage accumulation probably by reduction of cytokines. These data indicate that GTW is an effective agent for early MsPGN.展开更多
To study the sequential changes of HIF 1α (hypoxia inducible factor 1 alpha) in experimental spinal cord injury in rats and to analyze its potential effects in SCI. Methods: A static compression model of SCI was empl...To study the sequential changes of HIF 1α (hypoxia inducible factor 1 alpha) in experimental spinal cord injury in rats and to analyze its potential effects in SCI. Methods: A static compression model of SCI was employed in this study. Expressions of HIF 1α were measured with immunohistochemical staining, while flow cytometry was used to determine the apoptotic ratio and bcl 2 expre ssions. Results: HIF 1α began to increase 1 day after injury, and rea ched the peak at 3 7 days. Two weeks later, it declined significantly. The sequ ential changes of HIF 1α coincided well with the alterations of apoptotic rat io and contents of bcl 2. Conclusions: HIF 1α possibly participates in the secondary is chemic and hypoxic procedures after spinal cord injury, and may mediate the trau matic apoptosis. Further understanding of HIF 1α may provide new therapeuti c regimens for SCI.展开更多
基金Supported by Research Grant from the British Medical Research Council, Pfizer Global Research (Sandwich, UK) and the United Kingdom Department of Health Research and Development Fund. SM is funded by a clinical and research fellowship from the Société des Radiologistes de l’Hpital St-Franois d’Assise, Québec, Canada
文摘Ultrasound (US) is often the first imaging modality employed in patients with suspected focal liver lesions. The role of US in the characterisation of focal liver lesions has been transformed with the introduction of specific contrast media and the development of specialized imaging techniques. Ultrasound now can fully characterise the enhancement pattern of hepatic lesions, similar to that achieved with contrast enhanced multiphasic computed tomography (CT) and magnetic resonance imaging (MRI). US contrast agents are safe, well-tolerated and have very few contraindications. Furthermore, real-time evaluation of the vascularity of focal liver lesions has become possible with the use of the newer microbubble contrast agents. This article reviews the enhancement pattern of the most frequent liver lesions seen, using the second generation US contrast media. The common pitfalls for each type of lesion are discussed. The recent developments in US contrast media and specific imaging techniques have been a major advance and this technique, in view of the intrinsic advantages of US, will undoubtedly gain popularity in the years to come.
基金Supported by the National Natural Science Foundation of China, No. 30170105
文摘AIM: To investigate the pharmacological effects of rice flavone (5,4'-dihydroxy-3',5'-dimethoxy-7-0-β-D-glucopyranosyloxy-flavone, RF) separated from panicle-differentiating to flowing rice on rat experimental hepatic injury. METHODS: Models of rat acute hepatic injury induced by carbon tetrachloride (CCl4) administration, rat hepatic fibrosis induced by thioacetamide, injury of primary cultured rat hepatocytes induced by CCl4, respectively, were established. After treated with RF, content of serum alanine transaminase (ALT), aspartate aminotransferase (AST) and albumin (Alb), hyaluronic acid (HA), the activity of glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), and hydroxyproline (Hyp) were measured and liver tissue was observed pathologically by hematoxylin-eosin (HE) staining. Effects of RF on pathological changes, function index, enzyme of scavenging free radicals and blood rheology were evaluated. RESULTS: In model of rat acute hepatic injury induced by CCI4, RF can significantly decrease the contents of serum ALT, AST, increase the content of Alb, improve the dropsy and fat denaturalization of hepatocytes. In model of rat hepatic fibrosis induced by thioacetamide, RF can inhibit the increase of HA, Hyp and whole blood viscosity, and improve the activities of GSH-Px and SOD, and inauricular microcirculation. CONCLUSION: RF has apparent protective effects on hepatic injury by increasing activity of GSH-Px and SOD, scavenging free radicals produced by CCI4, reducing blood viscosity, and improving microcirculation and blood supply.
文摘AIM:This study investigated the mechanisms of protection afforded by the proton pump inhibitor lansoprazole against gastric injury induced by different non-steroidal anti-inflammatory drugs (NSAIDs) in rats. METHODS: Male Sprague-Dawley rats were orally treated with indomethacin (100 μmol/kg), diclofenac (60 μmol/kg), piroxicam (150 μmol/kg) or ketoprofen (150 μmol/kg). Thirty minutes before NSAIDs, animals were orally treated with lansoprazole 18 or 90 umol/kg. Four hours after the end of treatments, the following parameters were assessed: gastric mucosal PGE2, malondialdehyde (MDA), myeloperoxidase (MPO) or non-proteic sulfhydryl compounds (GSH) levels; reverse transcription-polymerase chain reaction (RT-PCR) of mucosal COX-2 mRNA; gastric acid secretion in pylorus-ligated animals; in vitro effects of lansoprazole (1-300 μmol/L) on the oxidation of low density lipoproteins (LDLs) induced by copper sulphate. RESULTS: All NSAIDs elicited mucosal necrotic lesions which were associated with neutrophil infiltration and reduction of PGE2 levels. Increments of MPO and MDA contents, as well as a decrease in GSH levels were detected in the gastric mucosa of indomethacin- or piroxicam-treated animals. Indomethacin enhanced mucosal cyclooxygenase-2 expression, while not affecting cyclooxygenase-1. At the oral dose of 18 μmol/kg lansoprazole partly counteracted diclofenac-induced mucosal damage, whereas at 90 μmol/kg it markedly prevented injuries evoked by all test NSAIDs. Lansoprazole at 90 μmol/kg reversed also the effects of NSAIDs on MPO, MDA and GSH mucosal contents, without interfering with the decrease in PGE2 levels or indomethacin-induced cyclooxygenase-2 expression. However, both lansoprazole doses markedly inhibited acid secretion in pylorus-ligated rats. Lansoprazole concentration-dependently reduced the oxidation of LDLs in vitro. CONCLUSION: These results suggest that, besides the inhibition of acid secretion, lansoprazole protection against NSAID-induced gastric damage depends on a reduction in mucosal oxidative injury, which is also responsible for an increment of sulfhydryl radical bioavailability. It is also suggested that lansoprazole does not influence the down-regulation of gastric prostaglandin production associated with NSAID treatment.
基金Sponsored by the Fundamental Research Foundation of Harbin Engineering University(Grant No.HEUFT07007)
文摘To investigate the relation between material＇s cychc plastic behaviour and fatigue crack growth, a new model is proposed. The model incorporated the two intrinsic properties of material＇ s cyclic plastic and crack tip＇ s deformation dislocation to interpret fatigue crack threshold. The relation between material＇ s cyclic hardening parameters （cyclic hardening amplitude and cyclic hardening rate） and fatigue threshold is studied. Fatigue threshold is determined based on the dislocation-free zone （DFZ） model, the theory of cohesive zone and the cyclic deformation behaviour. The results show that fatigue threshold increases with the decrease of the amplitude of cyclic hardening and is independent of cyclic hardening rate, but fatigue crack growth rate increases with the increase of cyclic hardening rate.
文摘To examine the effect of multi-glycoside of Tripterygium wilfordii Hook. f. （GTW） on proteinuria and acute glomerular immune lesion in experimental mesangial proliferative glomerulonephritis （MsPGN） induced by anti-Thyl. 1 monoelonal antibody （mAb） 1-22-3. The reversible model of MsPGN with anti-Thyl. 1 mAb 1-22-3 was established. After 7 days of oral treatment with GTW （ 100 mg/kg per day） and vehicle （distilled water, 5 ml/kg per day）, its effects on proteinuria, renal functions, mesangial morphological change, glomerular macrophage accumulation, and mRNA expressions of cytokines （PDGF-BB and MCP-1 ） were evaluated by light microscope （LM）, immunofluorescence （IF）, and reverse transcription polymerase chain reaction （RT-PCR）. It was found that GTW ameliorated proteinuria （on day 3 and day 7）, mesangial proliferation （total cell number, matrix expansion, a-smooth muscle actin expression, and collagen type Ⅰ expression） and macrophage accumulation （ED3^＋ ） in experimental MsPGN. In addition, GTW significantly suppressed the increased mRNA expressions for MCP-1 （67.6% to eontrol group, P 〈 0.01） together with the tendency to reduce the expression of PDGF （24.44% to control group） on day 7. It is concluded that GTW can not only decrease proteinuria, but also ameliorate acute mesangial alterations and glomerular activated macrophage accumulation probably by reduction of cytokines. These data indicate that GTW is an effective agent for early MsPGN.
基金ThisworkwassupportedbyagrantfromtheNationalNaturalScienceFoundationofChina (No .3 9970 75 5 )
文摘To study the sequential changes of HIF 1α (hypoxia inducible factor 1 alpha) in experimental spinal cord injury in rats and to analyze its potential effects in SCI. Methods: A static compression model of SCI was employed in this study. Expressions of HIF 1α were measured with immunohistochemical staining, while flow cytometry was used to determine the apoptotic ratio and bcl 2 expre ssions. Results: HIF 1α began to increase 1 day after injury, and rea ched the peak at 3 7 days. Two weeks later, it declined significantly. The sequ ential changes of HIF 1α coincided well with the alterations of apoptotic rat io and contents of bcl 2. Conclusions: HIF 1α possibly participates in the secondary is chemic and hypoxic procedures after spinal cord injury, and may mediate the trau matic apoptosis. Further understanding of HIF 1α may provide new therapeuti c regimens for SCI.
