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71.
Jia XL Li SY Dang SS Cheng YA Zhang X Wang WJ Hughes CE Caterson B 《World journal of gastroenterology : WJG》2012,18(30):3962-3976
AIM: To investigate the expression of chondroitin sulphate proteoglycans (CSPGs) in rat liver tissues of hepatocellular carcinoma (HCC).METHODS: Thirty male Sprague Dawley rats were randomly divided into two groups: control group (n = 10) and HCC model group (n = 20). Rats in the HCC model groups were intragastrically administrated with 0.2% (w/v) N-diethylnitrosamine (DEN) every 5 d for 16 wk, whereas 0.9% (w/v) normal saline was administered to rats in the control group. After 16 wk from the initiation of experiment, all rats were killed and livers were collected and fixed in 4% (w/v) paraformaldehyde. All tissues were embedded in paraffin and sectioned. Histological staining (hematoxylin and eosin and Toluidine blue) was performed to demonstrate the onset of HCC and the content of sulphated glycosaminoglycan (sGAG). Immunohistochemical staining was performed to investigate the expression of chondroitin sulphate (CS)/dermatan sulphate (DS)-GAG, heparan sulphate (HS)-GAG, keratan sulphate (KS)-GAG in liver tissues. Furthermore, expression and distribution of CSPG family members, including aggrecan, versican, biglycan and decorin in liver tissues, were also immunohistochemically determined.RESULTS: After 16 wk administration of DEN, malignant nodules were observed on the surface of livers from the HCC model group, and their hepatic lobule structures appeared largely disrupted under microscope. Toluidine blue staining demonstrated that there was an significant increase in sGAG content in HCC tissues when compared with that in the normal liver tissues from the control group [0.37 ± 0.05 integrated optical density per stained area (IOD/area) and 0.21 ± 0.01 IOD/area, P < 0.05]. Immunohistochemical studies demonstrated that this increased sGAG in HCC tissues was induced by an elevated expression of CS/DS (0.28 ± 0.02 IOD/area and 0.18 ± 0.02 IOD/area, P < 0.05) and HS (0.30 ± 0.03 IOD/area and 0.17 ± 0.02 IOD/area, P < 0.01) but not KS GAGs in HCC tissues. Further studies thereby were performed to investigate the expression and distribution of several CSPG components in HCC tissues, including aggrecan, versican, biglycan and decorin. Interestingly, there was a distinct distribution pattern for these CSPG components between HCC tissues and the normal tissues. Positive staining of aggrecan, biglycan and decorin was localized in hepatic membrane and/or pericellular matrix in normal liver tissues; however, their expression was mainly observed in the cytoplasm, cell membranes in hepatoma cells and/or pericellular matrix within HCC tissues. Semi-quantitative analysis indicated that there was a higher level of expression of aggrecan (0.43 ± 0.01 and 0.35 ± 0.03, P < 0.05), biglycan (0.32 ± 0.01 and 0.25 ± 0.01, P < 0.001) and decorin (0.29 ± 0.01 and 0.26 ± 0.01, P < 0.05) in HCC tissues compared with that in the normal liver tissues. Very weak versican positive staining was observed in hepatocytes near central vein in normal liver tissues; however there was an intensive versican distribution in fibrosis septa between the hepatoma nodules. Semi-quantitative analysis indicated that the positive rate of versican in hepatoma tissues from the HCC model group was much higher than that in the control group (33.61% and 21.28%, P < 0.05). There was no positive staining in lumican and keratocan, two major KSPGs, in either normal or HCC liver tissues.CONCLUSION: CSPGs play important roles in the onset and progression of HCC, and may provide potential therapeutic targets and clinical biomarkers for this prevalent tumor in humans. 相似文献
72.
Chu J Sun Y Zhao Y Wei W Wang J Liu X Jia Y Mao K Pu J Zhang S 《Journal of cardiovascular electrophysiology》2012,23(8):840-845
Identification of the Slow Conduction Zone in a Macroreentry. Background: Although idiopathic left ventricular tachycardia (ILVT) has been shown to possess a slow conduction zone (SCZ), the details of the electrophysiological and anatomic aspects are still not well understood. Objective: We hypothesized that the SCZ can be identified using a 3‐dimensional electroanatomic (EA) mapping system. Methods : Ten patients with ILVT were mapped using a 3‐dimensional electroanatomic (EA) mapping system. After a 3‐dimensional endocardial geometry of the left ventricular was created, the conduction system with left Purkinje potential (PP) and the SCZ with diastolic potential (DP) in LV were mapped during sinus rhythm (SR) and ventricular tachycardia (VT) and were tagged as special landmarks in the geometry. The electrophysiological and anatomic aspects of it were investigated. Results: EA mapping during SR and VT was successfully performed in 7 patients, during VT in 3 patients. The SCZ with DPs located at the inferoposterior septum was found in 7 patients during SR and all patients during VT. The length of the SCZ was 25.2 ± 2.3 mm with conduction velocity 0.08 ± 0.01 m/s. No differences in these parameters were found between patients during SR and VT (P > 0.05). An area with PP was found within the posterior septum. A crossover junction area with DP and PP was found in 7 patients during SR and VT. This area with DP and PP during SR coincided or were in proximity to such area during VT and radiofrequency ablation targeting the site within the area abolished VT in all patients. Conclusion: The ILVT substrate within the junction area of the SCZ and the posterior fascicular can be identified and can be used to guide the ablation of ILVT. (J Cardiovasc Electrophysiol, Vol. 23, pp. 840‐845, August 2012) 相似文献
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BackgroundKupffer cells and related cytokines are thought to play a critical role in liver fibrosis; however, the role played by Kupffer cells in hepatitis B virus-related fibrogenesis is unknown.MethodsPrimary rat Kupffer cells were cultured with different titres of hepatitis B virus particles and the concentrations of transforming growth factor (TGF)-β1, interleukin (IL)-1, IL-6 and tumour necrosis factor (TNF)-α in the culture supernatant were measured every 24 h for 7 days. The mRNA and protein levels of these cytokines in Kupffer cells were also analysed using quantitative real-time polymerase chain reaction and western blotting, respectively.ResultsKupffer cells maintained normal morphology and function throughout the 7-day exposure to hepatitis B virus. The concentration of TGF-β1 secreted by hepatitis B virus-stimulated Kupffer cells (6 log IU/ml hepatitis B virus) increased 5.38- and 7.75-fold by Days 3 and 7, respectively (p < 0.01). Western blotting showed that TGF-β1 expression in Kupffer cells exposed to high titres of hepatitis B virus increased 1.80- and 2.42-fold by Days 3 and 7, respectively (p < 0.01). In contrast, Kupffer cell expression and secretion of pro-inflammatory cytokines (IL-6, IL-1 and TNF-α) was unchanged throughout the experiment.ConclusionHepatitis B virus preferentially stimulates Kupffer cells to produce the pro-fibrogenic/anti-inflammatory cytokine TGF-β1 rather than the pro-inflammatory cytokines IL-6, IL-1 and TNF-α. This may partly explain why overt liver fibrosis still presents in cases of chronic hepatitis B virus infection with minimal (or no) necro-inflammation. 相似文献
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正摘要目的本研究目的是在3 T MR上,采用最具可重复性兴趣区(ROI)的方法,阐明直肠癌组织病理学类型与扩散参数之间的相关性。方法113例病人行扩散峰度成像 相似文献
80.
Purpose: The intraorbital wooden foreign body is often misdiagnosed or missed on computed tomography (CT) scan, due to the invisible or unclear images. The residual foreign bodies often occur during
surgical removal. The clinical manifestations, imaging features and treatment of intraorbital wooden
foreign bodies were discussed in this study.
Method: We retrospectively analyzed 14 cases of intraorbital wooden foreign bodies managed at our
hospital between January 2007 and May 2015. All patients underwent orbital CT examination before
surgery, and surgery was performed under general anesthesia with orbital wound debridement and
suture, as well as exploration and removal of wooden foreign bodies.
Results: At first, 11 cases underwent removal of foreign bodies, including 1 case with incomplete
removal and then receiving a secondary surgery. Foreign bodies were not found in three cases with
preoperative misdiagnosis and orbital MRI found residual foreign bodies in the orbit. Operations were
performed via primary wound approach in eight cases, conjunctival approach in two cases, and
anterior orbitotomy in four cases. Postoperatively, one case was complicated with eye injuries, three
cases with ocular muscle injuries, eight cases with visual loss, and eight cases with orbital abscess. The length of foreign bodies ranged from 1.8 cm to 11.0 cm. The maximum of four foreign bodies were removed at the same time.
Conclusion: Because the imaging of orbital wooden foreign bodies is complex and varied, MRI should be
combined when they are invisible on CT scan. At the same time injuries trajectory and clinical manifestations of patients should be taken into account. Surgical exploration should be extensive and thorough, and foreign bodies and orbital abscess must be cleared. 相似文献