Low NO bioavailability in CCl(4 )cirrhotic rat livers might result from low NO synthesis combined with decreased superoxide dismutase activity allowing superoxide-mediated NO breakdown: A comparison of two portal hypertensive rat models with healthy controls

BACKGROUND: In cirrhotic livers, the balance of vasoactive substances is in favour of vasoconstrictors with relatively insufficient nitric oxide. Endothelial dysfunction has been documented in cirrhotic rat livers leading to a lower activity of endothelial nitric oxide synthase but this might not be sufficient to explain the low nitric oxide presence. We compared the amount of all nitric oxide synthase isoforms and other factors that influence nitric oxide bioavailability in livers of two portal hypertensive rat models: prehepatic portal hypertension and carbon tetrachloride induced cirrhosis, in comparison with healthy controls. RESULTS: Endothelial nitric oxide synthase was the solely detected isoform by Western blotting in all livers. In cirrhotic livers, the amount of endothelial nitric oxide synthase protein was lower than in healthy controls, although an overlap existed. Levels of caveolin-1 messenger RNA were within the normal range but endothelin-1 messenger RNA levels were significantly higher in cirrhotic livers (p < 0.05). A markedly lower superoxide dismutase activity was observed in cirrhotic livers as compared to healthy controls (p < 0.05). CONCLUSIONS: In contrast to prehepatic portal hypertension, cirrhotic livers had decreased endothelial nitric oxide synthase protein and enhanced endothelin-1 messenger RNA amount. We hypothesise that a vasodilator/vasoconstrictor imbalance may be further aggravated by the reduced activity of superoxide dismutase. Decreased activity allows enhanced superoxide action, which may lead to breakdown of nitric oxide in liver sinusoids

Payers' views of the changes arising through the possible adoption of adaptive pathways

Payers are a major stakeholder in any considerations and initiatives concerning adaptive licensing of new medicinal products, also referred to as Medicines Adaptive Pathways to patients (MAPPs). Firstly, the scope and necessity of MAPPs need further scrutiny, especially with regard to the definition of unmet need. Conditional approval pathways already exist for new medicines for seriously debilitating or life-threatening diseases and only a limited number of new medicines are innovative. Secondly, MAPPs will result in new medicines on the market with limited evidence about their effectiveness and safety. Additional data are to be collected after approval. Consequently, adaptive pathways may increase the risk of exposing patients to ineffective or unsafe medicines. We have already seen medicines approved conventionally that subsequently proved ineffective or unsafe amongst a wider, more co-morbid population as well as medicines that could have been considered for approval under MAPPs but subsequently proved ineffective or unsafe in Phase III trials and were never licensed. Thirdly, MAPPs also put high demands on payers. Routine collection of patient level data is difficult with high transaction costs. It is not clear who will fund these. Other challenges for payers include shifts in the risk governance framework, implications for evaluation and HTA, increased complexity of setting prices, difficulty with ensuring equity in the allocation of resources, definition of responsibility and liability and implementation of stratified use. Exit strategies also need to be agreed in advance, including price reductions, rebates, or reimbursement withdrawals when price premiums are not justified. These issues and concerns will be discussed in detail including potential ways forward

BeNeLuxA Task Force chair discusses cross-border collaboration

status: publishe

The use of national reimbursement reports to support formulary decisions of the hospital's Drug and Therapeutics Committee : a comparative analysis

Background New therapies that do not reach patients in need, have not achieved their goal. Drug and Therapeutics Committees in hospitals ensure access to patients by compiling a formulary on rational grounds. An evolving landscape of innovative molecules challenges timely formulary adaptation after national reimbursement. Aim To integrate national reimbursement reports in the hospital's appraisal, thereby promoting access for patients without delay. Method For 2019, the rationale for new molecules at Ghent University Hospital, Belgium, was compared with the public assessment report of the National Institute for Health and Disability Insurance, assessing a medicine in a specific indication following a reimbursement request by the manufacturer. Decision criteria (therapeutic value and cost) between matching medicines in both databases (national & hospital) were retrospectively compared [no (%), mean (SD)]. Results Two-hundred public reports and 30 formulary decisions were analysed (with antineoplastic & immunomodulating as most prevalent class: 41.0% resp. 36.7%). National decision often concerned hospital-only medicines (89; 44.5%) without patient co-payment (101; 50.5%). Of 13 matched medicines (same indication), time delay between national decision and formulary admission was on average 3.1 (SD 2.3) months. Comparative analysis showed that assessment in both committees was mostly based on the efficacy endpoints of Randomised Controlled Trials. Literature used in hospital appraisals was of more recent publication date: + 0.78 (SD 2.2) years. Using public reports as a horizon scan could enable quick identification of new indications. Conclusion To speed up patient access, the scientific evidence of national reimbursement reports can be used for the purpose of hospital formulary decisions

Pathways of arginine biosynthesis in extreme thermophilic archaeo- and eubacteria

The pathway of arginine biosynthesis was investigated in two thermophilic eubacteria, Thermus aquaticus and Thermotoga maritima, and in two thermophilic archaeobacteria, Sulfolobus solfataricus and Pyrococcus furiosus. In the first three organisms, arginine biosynthesis proceeds via N-acetylated intermediates as in mesophilic micro-organisms. Only the enzymes catalysing the three last steps of the pathway could be detected in P. furiosus. The two eubacterial strains possess an ornithine acetyltransferase and are thus able to recycle the acetyl group from acetylornithine to glutamate. The archaeobacterium, S. solfataricus, uses the linear pathway in which the formation of ornithine is mediated by the hydrolytic enzyme acetylornithinase. Repression of enzyme synthesis by arginine was observed for most of the enzymes tested in T. aquaticus and S. solfataricus. Feedback inhibition by arginine was shown only in the ornithine acetyltransferase from T. aquaticus. This inhibition pattern is of interest since it would be the first example of control of arginine biosynthesis at this particular step. Data concerning the thermal stability of the arginine biosynthetic enzymes are presented.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

A Panel to Predict Long-term Outcome of Infliximab Therapy for Patients With Ulcerative Colitis

Infliximab is effective for patients with refractory ulcerative colitis (UC), but few factors have been identified that predict long-term outcome of therapy. We aimed to identify a panel of markers associated with outcome of infliximab therapy to help physicians make personalized treatment decisions.publisher: Elsevier articletitle: A Panel to Predict Long-term Outcome of Infliximab Therapy for Patients With Ulcerative Colitis journaltitle: Clinical Gastroenterology and Hepatology articlelink: http://dx.doi.org/10.1016/j.cgh.2014.07.055 content_type: article copyright: Copyright © 2015 AGA Institute. Published by Elsevier Ltd. All rights reserved.status: publishe

Anti-Tau Monoclonal Antibodies Derived from Soluble and Filamentous Tau Show Diverse Functional Properties in vitro and in vivo

The tau spreading hypothesis provides rationale for passive immunization with an anti-tau monoclonal antibody to block seeding by extracellular tau aggregates as a disease-modifying strategy for the treatment of Alzheimer's disease (AD) and potentially other tauopathies. As the biochemical and biophysical properties of the tau species responsible for the spatio-temporal sequences of seeding events are poorly defined, it is not yet clear which epitope is preferred for obtaining optimal therapeutic efficacy. Our internal tau antibody collection has been generated by immunizations with different tau species: aggregated-and non-aggregated tau and human postmortem AD brain-derived tau fibrils. In this communication, we describe and characterize a set of these anti-tau antibodies for their biochemical and biophysical properties, including binding, tissue staining by immunohistochemistry, and epitope. The antibodies bound to different domains of the tau protein and some were demonstrated to be isoform-selective (PT18 and hTau56) or phospho-selective (PT84). Evaluation of the antibodies in cellular-and in vivo seeding assays revealed clear differences in maximal efficacy. Limited proteolysis experiments support the hypothesis that some epitopes are more exposed than others in the tau seeds. Moreover, antibody efficacy seems to depend on the structural properties of fibrils purified from tau Tg mice-and postmortem human AD brain.</p