2,268 research outputs found
Technologies, texts and subjects: William S. Burroughs and post-humanism
No full textThis thesis addresses the twin questions of technology and the human, ultimately questioning the validity of either category and pointing toward their dissolution in transhumanism. Starting with a discussion of the question of technology in organization studies, the thesis takes issue with the way in which discussion has focused on the technology- object pole of a dualism at the neglect of the human subject that occupies the opposing pole. Following a methodological call for symmetry the thesis reconsiders the question of technology in light of its human other and visa versa. Working with the ideas of Friedrich Nietzsche and Deleuze and Guattari, the thesis suggests that there is a problem with maintaining a distinct conception of the human, separated a priori from questions of technology and language. In seeking to avoid an essentialism either of the (technological) object, or the (human) subject, the thesis reconsiders the question of the human, language and technics through an examination of the work of William S. Burroughs. Combining Burroughs' ideas with those of Deleuze and Guattari, a conception of the 'transhuman' is developed which, in opposition to a transcendental humanism, articulates the immanent implication of technology and language in the production of subjectivity, and points to the more radical potentials of new technology in figuring alternative modes of subjectivization and social organization
New insights into the coagulopathy of liver disease and liver transplantation
No full textThe liver is an essential player in the pathway of coagulation in both primary and secondary haemostasis. Only von Willebrand factor is not synthetised by the liver, thus liver failure is associated with impairment of coagulation. However, recently it has been shown that the delicate balance between pro and antithrombotic factors synthetised by the liver might be reset to a lower level in patients with chronic liver disease. Therefore, these patients might not be really anticoagulated in stable condition and bleeding may be caused only when additional factors, such as infections, supervene. Portal hypertension plays an important role in coagulopathy in liver disease, reducing the number of circulating platelets, but platelet function and secretion of thrombopoietin have been also shown to be impaired in patients with liver disease. Vitamin K deficiency may coexist, so that abnormal clotting factors are produced due to lack of gamma carboxylation. Moreover during liver failure, there is a reduced capacity to clear activated haemostatic proteins and protein inhibitor complexes from the circulation. Usually therapy for coagulation disorders in liver disease is needed only during bleeding or before invasive procedures. When end stage liver disease occurs, liver transplantation is the only treatment available, which can restore normal haemostasis, and correct genetic clotting defects, such as haemophilia or factor V Leiden mutation. During liver transplantation haemorrage may occur due to the pre-existing hypocoagulable state, the collateral circulation caused by portal hypertension and increased fibrinolysis which occurs during this surgery
Veno occlusive disease: up-date on clinical menagement.
No full textHepatic veno-occlusive disease is a clinical syndrome characterized by hepatomegaly, ascites, weight gain and jaundice, due to sinusoidal congestion which can be caused by alkaloid ingestion, but the most frequent cause is haematopoietic stem cell transplantation (STC) and is also seen after solid organ transplantation. The incidence of veno occlusive disease (VOD) after STC ranges from 0 to 70%, but is decreasing. Survival is good when VOD is a mild form, but when it is severe and associated with an increase of hepatic venous pressure gradient > 20 mmHg, and mortality is about 90%. Prevention remains the best therapeutic strategy, by using non-myeloablative conditioning regimens before STC. Prophylactic administration of ursodeoxycholic acid, being an antioxidant and antiapoptotic agent, can have some benefit in reducing overall mortality. Defibrotide, which has pro-fibrinolytic and antithrombotic properties, is the most effective therapy; decompression of the sinusoids by a transjugular intrahepatic portosystemic shunt (TIPS) can be tried, especially to treat VOD after liver transplantation and when multiorgan failure (MOF) is not present. Liver transplantation can be the last option, but can not be considered a standard rescue therapy, because usually the concomitant presence of multiorgan failure contraindicates this procedure
Survival following the development of ascites and/or peripheral oedema in primary biliary cirrhosis: a staged prognostic model.
No full textOBJECTIVE: Current prognostic models in primary biliary cirrhosis (PBC) have low precision, partly due to the restricted inclusion criteria of some cohorts used for modelling but also because of the prolonged natural course of the disease. It is hypothesized that better precision could be achieved with a staged model, using ascites or peripheral oedema as a new starting-point for prediction. MATERIAL AND METHODS: The study was based on an established database of 289 consecutive patients, followed between 1977 and 1998. Stepwise Cox regression was used to construct a staged model based on 143 patients who first developed ascites (n=111) or peripheral oedema (n=32) at entry or during subsequent follow-up. The model was compared with published models using graphical methods and receiver operating characteristics (ROCs). RESULTS: Mean time from clinical diagnosis of ascites or peripheral oedema to death was 3.1 years. The following variables had independent prognostic significance: log10(bilirubin) (p<0.001), albumin (p<0.001), age (p<0.001) and history of encephalopathy (p<0.001). Goodness of fit showed that the survival probabilities predicted by the Ascites Stage Model fitted well with the observed data. The Ascites Stage Model (ROC 0.8324 (SE 0.0348)) was a better predictor of survival than the Mayo long-term model (ROC 0.7833 (SE 0.0397)), the Mayo Repeated Patient Visits Model (ROC 0.7779 (SE 0.0399)) and the Royal Free PBC Prognostic Model (ROC 0.7785 (SE 0.0396)). CONCLUSIONS: The Ascites Stage Model gives a better survival estimate for PBC patients once they have developed ascites or peripheral oedema compared with the current models, and demonstrates an advantage of staged models in diseases with a prolonged natural history
Predicting the advent of ascites and other complications in primary biliary cirrhosis: a staged model approach.
No full textBACKGROUND: Current survival models for primary biliary cirrhosis have limited precision for medium and long-term survival. Aim To describe a prognostic model for the advent of complications in primary biliary cirrhosis as the first approach to a staged prognostic model. METHODS: From an established database of 289 consecutive primary biliary cirrhosis patients referred to Royal Free Hospital over 12 years (mean follow-up of 4.1 years), baseline characteristics at referral were evaluated by Cox-proportional hazards regression modelling. RESULTS: The following complications occurred de novo: 85 ascites/peripheral oedema, 40 oesophagogastric varices, 63 encephalopathy, 29 spontaneous bacterial peritonitis and/or septicaemia, 59 symptomatic urinary tract infections. Age, albumin, log(10)(bilirubin), presence of ascites at referral, variceal bleeding within 6 weeks before referral, detection of oesophagogastric varices at or before referral were significant at multivariate analysis with different combinations and coefficients for each complication. The model for predicting ascites and/or peripheral oedema best fitted the observed data (ROC = 0.7682, S.E. = 0.0385). CONCLUSIONS: The known prognostic factors in primary biliary cirrhosis also model the advent of complications. In view of the prognostic importance of ascites and its more robust statistical model, ascites and/or peripheral oedema could represent, following validation, the most suitable staged model in primary biliary cirrhosis to improve precision in survival modelling
Long-term ursodeoxycholic acid therapy for primary biliary cirrhosis: a follow-up to 12 years.
No full textBACKGROUND: It is uncertain whether ursodeoxycholic acid therapy slows down the progression of primary biliary cirrhosis, according to two meta-analyses. However, the randomized trials evaluated had only a median of 24 months of follow-up. AIM: To evaluate long-term ursodeoxycholic acid therapy in primary biliary cirrhosis. METHODS: We evaluated 209 consecutive primary biliary cirrhosis patients, 69 compliant with ursodeoxycholic acid and 140 untreated [mean follow-up 5.79 (s.d. = 4.73) and 4.87 (s.d. = 5.21) years, respectively] with onset of all complications documented. Comparison was made following adjustment for baseline differences according to Cox modelling, Mayo and Royal Free prognostic models. RESULTS: Bilirubin and alkaline phosphatase concentrations improved with ursodeoxycholic acid (at 36 months, P = 0.007 and 0.018, respectively). Unadjusted Kaplan-Meier analysis showed benefit (P = 0.028), as 44 (31%) untreated and 15 (22%) ursodeoxycholic acid patients died or had liver transplantation. However, there was no difference when adjusted by Cox modelling (P = 0.267), Mayo (P = 0.698) and Royal Free models (P = 0.559). New pruritus or fatigue or other complications were not different, either before or after adjustment for baseline characteristics. CONCLUSIONS: Long-term ursodeoxycholic acid therapy did not alter disease progression in primary biliary cirrhosis patients despite a significant improvement in serum bilirubin and alkaline phosphatase consistent with, and similar to, those seen in ursodeoxycholic acid cohorts in randomized trials
beta-Blockers protect against spontaneous bacterial peritonitis in cirrhotic patients: a meta-analysis
No full textINTRODUCTION:
Bacterial infections have been hypothetized to be a trigger of variceal bleeding in cirrhotic patients and beta-blockers may have a protective effect by decreasing bacterial translocation, reducing portal pressure. The aim of our study was to evaluate the possible role of beta-blockers in preventing spontaneous bacterial peritonitis (SBP) in patients with liver cirrhosis and ascites.
MATERIALS AND METHODS:
Extensive search of the literature including randomized controlled trial (RCT) and non-RCT of primary and secondary prophylaxis for variceal bleeding in cirrhotics using beta-blockers were evaluated. We performed a meta-analysis using the occurrence of SBP as endpoint in all the studies, using the random effect model.
RESULTS:
Three RCT and three retrospective studies in which beta-blockers were evaluated against no treatment for the prevention of SBP in ascitic cirrhotics were included. There was a statistically significant difference of 12.1%, P<0.001 in favour of propranolol in preventing SBP, which was confirmed by sensitivity analysis evaluating only RCTs (7.8% difference). The effect was still present when haemodynamic responders were compared with non-responders.
CONCLUSIONS:
This analysis suggests a role of beta-blockers in preventing SBP in ascitic cirrhotics, independent of haemodynamic response. Further formal RCTs are needed to confirm this finding
Interventional treatment should be incorporated in the algorithm for the management of patients with portal vein thrombosis
No full textOral propanolol decreases intestinal permeability in patients with cirrhosis: another protective mechanism against bleeding?
No full textCoagulation and fibrosis in chronic liver disease.
No full textIn the hepatic tissue repair mechanism, hepatic stellate cells (HSCs) are recruited at the site of injury and their changes reflect paracrine stimulation by all neighbouring cell types, including sinusoidal endothelial cells, Kupffer cells, hepatocytes, platelets and leucocytes. Thrombin converts circulating fibrinogen to fibrin, promotes platelet aggregation, is a potent activator of endothelial cells, acts as a chemoattractant for inflammatory cells and is a mitogen and chemoattractant for fibroblasts and vascular smooth muscle cells. Most of the cellular effects elicited by thrombin are mediated via a family of widely expressed G-protein-coupled receptors termed protease activated receptors (PARs). All known members of the PAR family stimulate cell proliferation/activation in a rat HSC line. Thrombin receptors are constitutively expressed in the liver, and their expression increases in parallel with the severity and/or the duration of liver disease. In human studies, thrombotic risk factors were found to be independently associated with the extent of fibrosis; severity of hepatitis C virus (HCV)-associated liver disease appears to be less in patients with haemophilia when compared with those with HCV alone. Several studies, based mostly on rat models, demonstrate that anticoagulants or antiplatelet agents prevent hepatic necrosis and fibrosis by acting on HSCs. These drugs could be therapeutic agents in patients with chronic liver disease and specific studies should be initiated
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