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101.
ObjectivesA recent debate in health economics and outcomes research community identified option value as one of the elements warranting consideration in the assessment of medical technologies. To conduct a scoping review of contributions on option value in the healthcare sector and identify relevant conceptual aspects and methods used to incorporate it in standard economic evaluations.MethodsA systematic search was conducted up to July 2020 to identify contributions from electronic bibliographic database and gray literature. Data on the proposed definitions of option value, theoretical implications of its use in economic evaluations, and methods used to estimate it were extracted and analyzed.ResultsWe found 57 eligible studies. Three different definitions emerged: insurance value, real option value, and option value of survival. Focusing on the latter (24 studies), we analyzed in depth 8 empirical applications across 7 therapeutic areas. The most relevant methodological challenges were on the perspective used in economic evaluations and how to robustly manage forecasting uncertainty, update cost-effectiveness thresholds, and avoid double-counting issues. For empirical studies assessing the total value of the technology, including option value, estimates ranged from +7% to +469% of its conventional value.ConclusionsThis review synthesizes theoretical and empirical aspects on option value of healthcare technologies and proposes a terminology to distinguish 3 different concepts identified. Future work should focus primarily on agreeing on whether option value should be included in economic evaluations and, if so, on developing and validating reliable methods for its ex-ante estimation.  相似文献   
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Sir, Idiopathic thrombocytopenic purpura (ITP) is often diagnosedin the elderly, but no specific guidelines exist for such patients.1Recent studies report that patient age may influence both therapeuticresponse and treatment-associated toxicity.2 We describe thepreliminary results of  相似文献   
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Summary Clinical cure of hemophilia A by orthotopic liver transplantation has been reported in 11 cases. We describe the first successful Italian case. A 27-year-old man had cirrhosis caused by previous infections with the hepatitis B, C and D viruses following life-long treatment with factor VIII concentrates made from large plasma pools. He was, however, seronegative for the human immunodeficiency virus. In the year before transplantation, life-threatening gastrointestinal bleeding due to severe esophageal varices required a large transfusion regimen (on average, 13 bags of red cell concentrates and 35,000 U of factor VIII/week). To perform orthotopic liver transplantation 8,000 U of factor VIII were given during surgery together with 10 bags of red cells and 11 of fresh-frozen plasma. Intraoperative bleeding was not different from that of non-hemophilic patients undergoing orthotopic liver transplantation. No additional factor VIII was used after transplantation and factor VIII levels in plasma were always above 50 U/dl, reaching the highest value of 184 U/dl on day 4 post transplantation. He was discharged from hospital 10 weeks after trans-plantation with factor VIII levels of 68 U/dl. All virological markers are currently negative, except anti-hepatitis C virus antibodies. In this patient orthotopic liver trans-plantation was a life-saving treatment for end-stage cirrhosis and a cure for hemophilia A.  相似文献   
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Activation of inflammatory pathways may contribute to the beginning and the progression of both atherosclerosis and type 2 diabetes. Here we report a novel interaction between insulin action and control of inflammation, resulting in glucose intolerance and vascular inflammation and amenable to therapeutic modulation. In insulin receptor heterozygous (Insr+/-) mice, we identified the deficiency of tissue inhibitor of metalloproteinase 3 (Timp3, an inhibitor of both TNF-alpha-converting enzyme [TACE] and MMPs) as a common bond between glucose intolerance and vascular inflammation. Among Insr+/- mice, those that develop diabetes have reduced Timp3 and increased TACE activity. Unchecked TACE activity causes an increase in levels of soluble TNF-alpha, which subsequently promotes diabetes and vascular inflammation. Double heterozygous Insr+/-Timp3+/- mice develop mild hyperglycemia and hyperinsulinemia at 3 months and overt glucose intolerance and hyperinsulinemia at 6 months. A therapeutic role for Timp3/TACE modulation is supported by the observation that pharmacological inhibition of TACE led to marked reduction of hyperglycemia and vascular inflammation in Insr+/- diabetic mice, as well as by the observation of increased insulin sensitivity in Tace+/- mice compared with WT mice. Our results suggest that an interplay between reduced insulin action and unchecked TACE activity promotes diabetes and vascular inflammation.  相似文献   
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BACKGROUND & AIMS: Caspases, a class of cysteine proteases, modulate apoptosis. Nitric oxide (NO)-releasing nonsteroidal anti-inflammatory drugs (NSAIDs) are a new class of NSAID derivatives with reduced gastrointestinal toxicity. The aim of this study was to investigate whether cysteine endoproteases are involved in the pathogenesis of NSAID gastropathy and are target for NO-aspirin (NCX-4016). METHODS: Rats were treated orally with aspirin or equimolar doses of NCX-4016. Caspase activities were measured by fluorometric assay. Apoptosis was quantified by an enzyme-linked immunosorbent assay for histone-associated DNA, DNA ladder on agarose gel, and terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling assay. A primary culture of gastric chief cells was used to investigate whether NCX-4016 modulates guanosine 3',5'-cyclic monophosphate (cGMP)-dependent pathways. RESULTS: Short- and long-term (7 days) aspirin administration resulted in a time- and dose-dependent gastric injury that was associated with apoptosis and caspase up-regulation. Z-VAD.FMK, a pancaspase inhibitor, and NO donors protected from acute damage induced by aspirin. NCX-4016 spared the gastric mucosa and caused caspase inactivation by S-nitrosylation. Inhibition of tumor necrosis factor (TNF)-alpha release or activity by TAPI-2 or anti-TNF-alpha receptor monoclonal antibodies protected against mucosal damage and caspase activation. NCX-4016 protected gastric chief cells from toxicity induced by TNF-alpha by activating cGMP-dependent pathways. CONCLUSIONS: Aspirin administration leads to a TNF-alpha-dependent activation of gastric caspases. NO-aspirin spares the gastric mucosa and inhibits caspase activity through cGMP-dependent and -independent pathways.  相似文献   
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Recurrent gastrointestinal bleeding is one of the most challenging complications encountered in the management of patients with von Willebrand disease (VWD). The commonest cause is angiodysplasia, but often no cause is identified due to the difficulty in making the diagnosis. The optimal treatment to prevent recurrences remains unknown. We performed a retrospective study of VWD patients with occult or angiodysplastic bleeding within the setting of the von Willebrand Disease Prophylaxis Network (VWD PN) to describe diagnostic and treatment strategies. Centres participating in the VWD PN recruited subjects under their care with a history of congenital VWD and gastrointestinal (GI) bleeding due to angiodysplasia, or cases in which the cause was not identified despite investigation. Patients with acquired von Willebrand syndrome or those for whom the GI bleeding was due to another cause were excluded. Forty‐eight patients from 18 centres in 10 countries were recruited. Seven individuals had a family history of GI bleeding and all VWD types except 2N were represented. Angiodysplasia was confirmed in 38%, with video capsule endoscopy and GI tract endoscopies being the most common methods of making the diagnosis. Recurrent GI bleeding in VWD is associated with significant morbidity and required hospital admission on up to 30 occasions. Patients were treated with multiple pharmacological agents with prophylactic von Willebrand factor concentrate being the most efficient in preventing recurrence of the GI bleeding. The diagnosis and treatment of recurrent GI bleeding in congenital VWD remains challenging and is associated with significant morbidity. Prophylactic treatment with von Willebrand factor concentrate was the most effective method of preventing recurrent bleeding but its efficacy remains to be confirmed in a prospective study.  相似文献   
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