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Target Drug (target + drug)
Selected AbstractsCPU-86017 improves the compromised blood,brain barrier permeability mediated by impaired endothelial no system and oxidative stress caused by L -thyroxineDRUG DEVELOPMENT RESEARCH, Issue 3 2005Rong-Hui Du Abstract Impaired endothelial cell (EC) function leads to alterations in the permeability of the blood,brain barrier (BBB). There are two aspects of the transport through the BBB: from the blood to the brain (influx) and from the brain to the blood (efflux). An impaired EC model induced by L -thyroxine that compromises the influx and efflux properties of the BBB was used to assess responses to the intervention of CPU-86017 (an antioxidant and calcium channel blocker) and propranolol. CPU-86017 (t1/2=1.5 h) was also used as a target drug, leaving no traces in the brain and blood 24 h after administration. The permeability of the BBB was evaluated by using CPU-86017 after iv and icv injection and concentrations in the blood and brain being measured by high-performance liquid chromatography. The bidirectional permeability of CPU-86017 was impaired and associated with a reduced NO bioavailability assessed functionally by the vasoactivity in the model. Partial relief of NO bioavailability and oxidative stress induced by propranolol was consistent with a recovery of BBB efflux alone. Complete recovery in the efflux and influx of the BBB by CPU-86017 was a result of the complete restoration of NO bioavailability and reduction in oxidative stress. Normal BBB influx is dependent on an intact endothelial NO system, and efflux could be restored easily by partial improvement of NO bioavailability. CPU-86017 is thus more effective than propranolol in protecting the endothelium from damage produced by L -thyroxine through oxidative stress. Drug Dev. Res. 64:145,156, 2005. © 2005 Wiley-Liss, Inc. [source] Pathology of gastrointestinal stromal tumorsPATHOLOGY INTERNATIONAL, Issue 1 2006Seiichi Hirota Gastrointestinal stromal tumors (GIST) are the most common mesenchymal tumors in the gastrointestinal tract. It was found that most GIST expressed KIT, a receptor tyrosine kinase encoded by protooncogene c- kit. In normal gastrointestinal wall, KIT is expressed by interstitial cells of Cajal (ICC), which are a pacemaker for autonomous gastrointestinal movement. Because both GIST and ICC are double-positive for KIT and CD34, and because familial and multiple GIST appear to develop from diffuse hyperplasia of ICC, GIST are considered to originate from ICC or their precursor cells. It was also found that approximately 90% of the sporadic GIST have somatic gain-of-function mutations of the c- kit gene, and that the patients with familial and multiple GIST have germline gain-of-function mutations of the c- kit gene. These facts strongly suggest that the c- kit gene mutations are a cause of GIST. Approximately half of the sporadic GIST without c- kit gene mutations were demonstrated to have gain-of-function mutations in platelet-derived growth factor receptor-, (PDGFRA) gene that encodes another receptor tyrosine kinase. Because KIT is immunohistochemically negative in a minority of GIST, especially in PDGFRA gene mutation-harboring GIST, mutational analyses of c- kit and PDGFRA genes may be required to diagnose such GIST definitely. Imatinib mesylate was developed as a selective tyrosine kinase inhibitor. It inhibits constitutive activation of mutated KIT and PDGFRA, and is now being used for KIT-positive metastatic or unresectable GIST as a molecular target drug. Confirmation of KIT expression by immunohistochemistry is necessary for application of the drug. The effect of imatinib mesylate is different in various types of c- kit and PDGFRA gene mutations, and the secondary resistance against imatinib mesylate is often acquired by the second mutation of the identical genes. Mutational analyses of c- kit and PDGFRA genes are also significant for prediction of effectiveness of drugs including newly developed agents. [source] Latest news and product developmentsPRESCRIBER, Issue 12 2007Article first published online: 4 OCT 200 NAO: GPs still not prescribing efficiently The National Audit Office (NAO) says NHS funds are being wasted through inefficient GP prescribing and patients not taking their medicines. The NAO's long-awaited report, Prescribing Costs in Primary Care (www.nao.org.uk), found large variations between PCTs in generic prescribing of statins, ACE inhibitors and angiotensin-II antagonists, and protonpump inhibitors; PCTs were also paying widely differing prices for these products. There was a five-fold variation in prescribing volume for clopidogrel between PCTs. These four drugs accounted for only 19 per cent of total spending but, if all practices matched the performance of the best 25 per cent, the NHS would save £200 million annually. PCTs should do more to rationalise prescribing and support their GPs, the NAO concludes. The NAO says that the cost of medicines dispensed for but not taken by patients lies somewhere in the range £100-£800 million annually. Strategies to reduce waste include public awareness campaigns and restricting supplies to four weeks (or two weeks for new medicines). Rosiglitazone may increase CV death risk A meta-analysis of 42 clinical trials has suggested that rosiglitazone is associated with increased risks of myocardial infarction (MI) and cardiovascular death (N Engl J Med 2007; published online 21 May: doi 10.1056/ NEJMoa072761). Like the COX-2 inhibitors, rosiglitazone was licensed without determining its possible effects on long-term cardiovascular outcomes, and interpretation of the latest findings is complicated by the multiple comparisons involved. For risk of MI, there was no significant difference between rosiglitazone and placebo (though this was of borderline statistical signifi-cance , p=0.07), metformin, sulphonylureas or insulin. Rosiglitazone was associated with a statistically significant 43 per cent increased risk compared with all comparators combined but the absolute increase in risk was very small (0.02 per cent). The trends were similar for risk of cardiovascular death, though rosiglitazone was associated with a 64 per cent increased risk compared with all comparators combined that was of borderline statistical significance (p=0.06). The authors acknowledge that their analysis pooled short-term studies that excluded patients at risk of heart disease and was not designed to determine cardiovascular outcomes, and they had no access to patientlevel data; as a result, there is uncertainty about their findings. Nevertheless, they say there is now an urgent need to clarify the risk associated with rosiglitazone. GlaxoSmithKline has rebutted the findings, stating that the cardiovascular risk profile of rosiglitazone is comparable with that of other oral antidiabetic drugs. The MHRA says warnings in the current SPCs for Avandia and Avandamet already reflect most of the data in the latest US review. The possible effects of rosiglitazone on cardiovascular events is currently being evaluated in the Rosiglitazone Evaluated for Cardiac Outcomes and Regulation of glycaemia in Diabetes (RECORD) study. Good management tool The Department of Health has published a disease management tool to enable PCTs to model local interventions that could reduce emergency admissions. The web-based ,voluntary good practice tool' will demonstrate how interventions in primary care and social care settings can improve the management of long-term conditions including cardiovascular disease, asthma and COPD, and dementia and depression. Counterfeit medicines The MHRA has issued an unprecedented three alerts about fake medicines in the legitimate supply chain, recalling all affected lot numbers. Three batches of Zyprexa 10mg tablets (olanzapine) were withdrawn after a company printing labels became suspicious and alerted Eli Lilly. Two of the batches, which contained 60 per cent of the stated active ingredient, had reached patients but no adverse events were reported. Two lots of parallel-imported Plavix 75mg tablets (clopidogrel) have been withdrawn after counterfeit packs were identified. The lots were in French original packaging but will have been overlabelled for the UK market. The counterfeits were mixed with genuine packs from Sanofi-Aventis. Fake Casodex 50mg tablets (bicalutamide) have been identified in a parallel import from France. The Royal Pharmaceutical Society reports that the fake contains 75 per cent of the stated dose of bicalutamide. Alcohol-free mometasone Schering-plough has introduced an alcohol-free formulation of mometasone furoate nasal spray (Nasonex) for hay fever. The company says that an alcohol vehicle causes nasal irritation and leaves an unpleasant aftertaste, adding that over 40 per cent of patients cite this as the main reason for stopping treatment, and over 50 per cent state a preference for an alcohol-free product. Aid to improve statin adherence Adherence to statin therapy can be improved if patients use a decision aid when they are offered treatment,US investigators say (Arch Intern Med 2007;167:1076-82). The decision aid estimated the individual's 10-year cardiovascular risk and the risk reduction from treatment, and summarised the disadvantages of statins.Patients with diabetes who used the aid knew more about their risk and were less indecisive about treatment than those who did not. The odds of having missed a dose over three months were three times higher for patients who had not used the aid. Online tool calculates switch savings A new online tool can help GPs estimate the savings achievable from switching patients to cheaper medicines. The Switch Saving Calculator, developed by the Prescribing Analysis & Support Team at the NHS Regional Drug and Therapeutics Centre in Newcastle, calculates potential savings based on past, current or projected use of the target drug. It can be applied to individual prescribers or scaled up to practice, commissioning group, PCT, health authority or even national level. Separate calculators are available for primary and secondary care. The current version calculates potential savings by switching from atorvastatin to simvastatin. The Newcastle team says other drugs will be added and they will update prices regularly. The calculator is at www.nyrdtc.nhs.uk:80/Services/presc_supp/ switch_saving_calculator/switch_saving_calculator.html. No improvement in drug information for patients leaving hospital The information given to patients discharged from hospital is not improving, according to the Healthcare Commission's annual patient survey (www.healthcare commission.org.uk). The 2006 survey found that the commonest reason patients were kept waiting for at least four hours to leave hospital was the delay in providing discharge medicines. Provision of written information increased from 62 per cent of patients in 2005 to 65 per cent in 2006. However, only 76 per cent said they had been told about their medicines in a way they could ,completely' understand (79 per cent in 2002). The proportion of patients reporting complete information about sideeffects also fell (from 40 per cent in 2005 to 37 per cent). Aspirin in preeclampsia A new meta-analysis has found that primary prevention with low-dose aspirin modestly but consistently reduces the risk of preeclampsia (Lancet 2007; published online 18 May). The study of 31 trials involving 32 217 women at low to moderate risk found that antiplatelet agents (mostly aspirin) reduced the risk of pre-eclampsia and preterm birth by 10 per cent without an increased risk of bleeding. The benefit was similar across subgroups. There were also nonsignificant reductions in the risk of small for age, stillborn and death before discharge. New from NICE NICE approves varenicline for NHS NICE has endorsed the use of varenicline (Champix) as an aid to smoking cessation within the NHS for England and Wales; it has already been approved for use in Scotland by the Scottish Medicines Consortium. Varenicline is a partial agonist at the ,4,2 nicotinic receptor. It alleviates craving and withdrawal symptoms, and reduces the rewarding and reinforcing effects of smoking. The commonest adverse effect is mild to moderate nausea, which improves with time.1 Varenicline is licensed for smoking cessation in adults; NICE says it should be offered as an option for smokers who say they want to quit as part of a programme of behavioural support. However, treatment should not be withheld if counselling and support are not available. NICE was critical of manufacturer Pfizer's economic arguments in favour of varenicline, which inappropriately included US data, assumed a single quit attempt and may have overestimated its efficacy. It nonetheless concluded that varenicline is more effective than nicotine replacement therapy (NRT) or bupropion (Zyban) in achieving continuous abstinence. NICE estimated that, compared with NRT, the odds of abstinence at one year with varenicline were 54 per cent greater. A Cochrane review1 concluded that abstinence was 66 per cent more likely with varenicline than with bupropion, and three times more likely than with placebo. There was also a benefit from offering smokers a wider choice of treatments. A 12-week course of varenicline costs £163.80; it is also licensed for an additional 12-week course and dose tapering may be considered for those at high risk of relapse. The final appraisal determination does not state which is the treatment of first choice for smoking cessation. NICE is currently preparing guidance on smoking cessation in pri-mary care, pharmacies and workplaces. Copyright © 2007 Wiley Interface Ltd [source] Electrokinetic supercharging-electrospray ionisation-mass spectrometry for separation and on-line preconcentration of hypolipidaemic drugs in water samplesELECTROPHORESIS, Issue 7 2010Mohamed Dawod Abstract Electrokinetic supercharging, a powerful on-line preconcentration technique in CE, was for the first time hyphenated with ESI-MS for the on-line concentration and separation of five hypolipidaemic drugs. The electrophoretic separation was performed in a co-EOF mode using the EOF reversal agent, hexadimethrine bromide, in ammonium bicarbonate electrolyte, pH 9.00. The ionic strength and the amount of methanol in the buffer were optimised in a multivariate manner using artificial neural networks, with the optimal conditions being 60,mM ammonium bicarbonate containing 60% methanol, providing baseline resolution of the five hypolipidaemics within 20,min. Using electrokinetic supercharging, the sensitivity of the method was improved 1000-fold over a conventional injection under field-amplified sample stacking conditions with LODs of 180,ng/L. This is the first report of the separation of hypolipidaemics by CE. The developed method was validated and then applied to the determination of the target drugs in water samples from Hobart city. [source] Effectiveness of educational interventions on the improvement of drug prescription in primary care: a critical literature reviewJOURNAL OF EVALUATION IN CLINICAL PRACTICE, Issue 2 2001Adolfo Figueiras PhD Abstract This paper is a critical review of studies of educational programmes designed to improve prescription practices in ambulatory care. Scientific articles were selected from the following bibliographical indices: MEDLINE, IME, ICYT and ERIC. The searches covered the time period between 1988 and 1997. The search criteria included: primary-care, educat*, prescription* and other related keywords. The inclusion criteria were studies describing educational strategies aimed at general practitioners working in ambulatory settings. The study outcome was change in prescribing behaviour of physicians through prescribing indicators. The following data were extracted: study design, target drugs, type of intervention, follow-up period of the prescription trends, type of data analysis, type of statistical analysis and reported results. We found 3233 articles that met the search criteria. Of these, 51 met the inclusion criteria and 43 studied the efficacy/effectiveness of one or various interventions as compared to no intervention. Among seven studies evaluating active strategies, four reported positive results (57%), as opposed to three of the eight studies assessing passive strategies (38%). Among the 28 studies that tested reinforced active strategies, 16 reported positive results for all variables (57%). Eight studies were classified as a high degree of evidence (16%). We concluded that the results of our review suggest that the more personalized, the more effective the strategies are. We observe that combining active and passive strategies results in a decrease of the failure rate. Finally, better studies are still needed to enhance the efficacy and efficiency of prescribing practices. [source] | ||||||||||