26 research outputs found
Acute effects of liver vein occlusion by stent-graft placed in transjugular intrahepatic portosystemic shunt channel: An experimental study
The purpose of this study was to evaluate the effects of hepatic vein occlusion by stent-graft used in transjugular intrahepatic portosystemic shunt (TIPS). The experiments were performed in six healthy pigs under general anesthesia. Following percutaneous transhepatic implantation of a port-a-cath in the right hepatic vein, TIPS was created with a stent-graft (Viatorr; W L Gore, Flagstaff, AZ, USA). The outflow from the hepatic vein, blocked by the stent-graft was documented by injection of contrast medium and repeated injections of 99Tc(m)-labeled human serum albumin through the port-a-cath. After 2 weeks, the outflow was re-evaluated, the pigs were sacrificed, and histopathologic examination of the liver was performed. Occlusion of the hepatic vein by a stent-graft had a short and temporary effect on the outflow. Histopathological examination from the affected liver segment showed no divergent pattern. Stent-grafts used in TIPS block the outflow from the liver vein, but do not have a prolonged circulatory effect and do not affect the liver parenchyma
Reduced expression of angiotensin II and angiotensin receptor type 1 and type 2 in resistance arteries from nasal lesions in granulomatosis with polyangiitis (Wegener's granulomatosis).
Objectives: Angiotensin II (ANGII) is involved in vessel inflammation and is important in the development of cardiovascular disorders such as atherosclerosis. During active disease, patients with granulomatosis with polyangiitis (GPA; Wegener's granulomatosis) have accelerated atherosclerosis and ANGII inhibitors are recommended to these patients to reduce atherosclerosis. We assessed the hypothesis that the expression of ANGII and its receptors in arteries in granulomatous lesions change in GPA. Methods: ANGII and angiotensin receptors were quantified in vessels from granulomatous lesions from patients with GPA using immunohistochemistry. Anti- ANGI type 1 (AT1) and type 2 (AT2) antibodies were applied on formalin-fixed and paraffin-embedded biopsies from nasal mucous membranes from eight patients with GPA and eight controls. Results: ANGII expression was localized to the endothelial cells (ECs) in arteries and sparsely to vascular smooth muscle cells (VSMCs) in nasal biopsies. AT1 receptor (AT1R) staining was intense and located in the VSMCs in the medial layer of the control arteries. AT2 receptor (AT2R) immunostaining was faint and was located only in the ECs. Patients with GPA showed marked down-regulation of positively immunostained ECs for ANGII or AT2R, and a reduced number of AT1R in VSMCs. ANGII, AT1R, and AT2R staining was persistent on infiltrating leucocytes. Conclusions: These results suggest down-regulation of the angiotensin system in arteries in granulomatous nasal lesions in GPA. Inhibition of the angiotensin system may prove less efficient in inhibiting the vascular inflammation process in GPA
Increased Tissue Endothelin-1 and Endothelin-B Receptor Expression in Temporal Arteries from Patients with Giant Cell Arteritis.
PURPOSE: Endothelin (ET)-1 has been implicated in the atherosclerotic process and during inflammation. Similarity in the development process of giant cell arteritis (GCA) and atherosclerosis exists. Several ET receptor antagonists have been developed, principally to target cardiovascular disease states. High doses of corticosteroids currently are used in the treatment of GCA, whereas other treatments are not as reliably effective. The present study was performed to elucidate the role for ET-1, ET(A), and ET(B) receptors in GCA. DESIGN: Experimental, retrospective immunohistochemical study of temporal arteries using archival formalin-fixed, paraffin-embedded tissue. PARTICIPANTS: The study included 10 patients with GCA and 10 control patients with clinically suspected GCA but diagnosed not to have GCA. METHODS: Immunohistochemistry, with anti ET-1, anti-ET(A), and anti-ET(B) antibodies, was performed on formalin-fixed and paraffin-embedded temporal arteries. MAIN OUTCOME MEASURES: Endothelin-1, ET(A), and ET(B) receptor immunostaining intensities were quantified. RESULTS: Temporal arteries from the patients with GCA showed the typical histologic features, including intimal thickening, disruption or loss of the elastic lamina, and inflammatory infiltrates of lymphocytes, macrophages, and multinucleated giant cells. These features were associated with increased ET-1 and ET(B) receptor immunoreactivity in the medial layer of the temporal arteries and endothelial cells in patients with GCA compared with the controls. The increased ET-1 and ET(B) receptor immunoreactivity occurred in vascular smooth muscle cells (SMCs) and multinucleated giant cells. The ET-1 and ET(B) receptor immunoreactivity correlated with the degree of systemic inflammation. No changes were observed in ET(A) receptor expression in SMCs or endothelial cells compared with controls. CONCLUSIONS: The results suggest a role for ET-1 and ET(B) receptors in GCA. Inhibiting the ET system may provide a corticosteroid-sparing alternative in the treatment of GCA. FINANCIAL DISCLOSURE(S): The authors have no proprietary or commercial interest in any materials discussed in this article
Early endoscopic assessment after esophagectomy can predict anastomotic complications : a novel scoring system
Background: Anastomotic leakage after esophagectomy is a serious and demanding complication. Early detection and treatment can probably prevent clinical deterioration of the patient. We have used early endoscopic assessment and a novel endoscopy score to predict anastomotic complications. Methods: 57 patients planned for Ivor Lewis esophagectomy were included. Endoscopy videos were recorded and biopsies were taken from the gastric conduit on day 7 or 8 after esophagectomy. A scoring system based on the endoscopic appearance, the combined endoscopy score (0–6), was developed. Scoring of the videos was done blinded. Patient outcome with regards to anastomotic complications was registered on postoperative day 30 in accordance with the ECCG definitions and compared to histopathology assessment and the combined endoscopy score retrospectively. Results: The rate of anastomotic defect (necrosis and leakage, ECCG definitions) was 19%. 7 out of 8 patients with a combined endoscopy score of ≥ 4 developed anastomotic defects. The combined endoscopy score was the only predictor for anastomotic complications. Conclusion: Prediction of anastomotic complications enables early detection and treatment which often limits the clinical extent of the complication. Early postoperative endoscopy is safe and a relatively simple procedure. The combined endoscopy score is an accurate tool to predict anastomotic complications
Increased angiotensin II type 1 receptor expression in temporal arteries from patients with giant cell arteritis
PURPOSE: Currently, giant cell arteritis (GCA) is primarily treated with corticosteroids or immunomodulating agents, but there is interest in identifying other noncorticosteroid alternatives. Similarities exist in the injury pathways between GCA and atherosclerosis. Angiotensin II is a vasoactive peptide involved in vessel inflammation during atherosclerosis, and angiotensin II receptor inhibitors are effective in preventing atherosclerosis. The present study was performed to elucidate the role of angiotensin type 1 (AT(1)) and type 2 (AT(2)) receptors in GCA. DESIGN: Experimental retrospective immunohistochemical study of temporal arteries using archival formalin-fixed, paraffin-embedded tissue. PARTICIPANTS: Ten patients with GCA and 10 control patients, who were clinically suspected of having GCA but were diagnosed as not having GCA, were included. METHODS: Immunohistochemistry, using anti-AT(1) and anti-AT(2) antibodies, was performed on formalin-fixed and paraffin-embedded temporal arteries. MAIN OUTCOME MEASURES: AT(1) and AT(2) receptor immunostaining intensity was quantified. RESULTS: Hematoxylin-eosin-stained sections of temporal arteries from patients with GCA showed intimal hyperplasia, internal elastic lamina degeneration, and band-shaped infiltrates of inflammatory cells, including lymphocytes, histocytes, and multinucleated giant cells. AT(1) receptor staining was primarily observed in the medial layer of the temporal arteries and was higher in the patients with GCA than in the control patients. This was a result of increased AT(1) receptor immunostaining of both vascular smooth muscle cells and infiltrating inflammatory cells. Only faint immunostaining was seen for AT(2) receptors, primarily in the endothelial cells, and to a lesser extent on the smooth muscle cells. Immunostaining with antibodies for the AT(2) receptor was similar in the patients with GCA and in controls. CONCLUSIONS: These results suggest that AT(1) receptors play a role in the development of GCA. Inhibition of the angiotensin system may thus provide a noncorticosteroid alternative for the treatment of GCA. FINANCIAL DISCLOSURE(S): The author(s) have no proprietary or commercial interest in any materials discussed in this article
Microcirculation changes during liver resection - A clinical study.
In this study we aimed to evaluate effects of liver resection on hepatic microcirculation. In addition we wanted to study if histological liver damage could be detected intra-operatively
Identification of low-risk tumours in histological high-grade soft tissue sarcomas
In more than one-third of patients with a histological high-grade malignant soft tissue sarcoma metastasis develops despite local control of the primary tumour. Hence, adjuvant chemotherapy is increasingly used for these relatively chemoresistant tumours which requires improved prognostication to exclude low-risk patients from overtreatment. We assessed the value of stepwise prognostication in a series of 434 histological high-grade STS of the extremity and trunk wall. Vascular invasion was used as the first discriminator whereafter the risk factors tumour necrosis, size (>8 cm) and infiltrating growth pattern were used to discriminate high- and low-risk tumours. We identified a high-risk group with a cumulative incidence of metastasis >0.4 at 5 years, and a low-risk group, comprising half of the tumours, with a cumulative incidence of metastasis <0.15. The model was validated in an independent material of 175 patients. This model improved prognostication in STS and is of value for identifying patients who probably should not receive adjuvant chemotherapy. (C) 2007 Elsevier Ltd. All rights reserved