The influence of ethylene and ethylene modulators on shoot organogenesis in tomato

[EN] The influence of ethylene and ethylene modulators on the in vitro organogenesis of tomato was studied using a highly regenerating accession of the wild tomato Solanum pennellii and an F1 plant resulting from a cross between Solanum pennellii and Solanum lycopersicum cv. Anl27, which is known to have a low regeneration frequency. Four ethylene-modulating compounds, each at four levels, were used, namely: cobalt chloride (CoCl 2), which inhibits the production of ethylene; AgNO 3 (SN), which inhibits ethylene action; and Ethephon and the precursor 1-aminocyclopropane-1-carboxylic acid (ACC), which both promote ethylene synthesis. Leaf explants of each genotype were incubated on shoot induction medium supplemented with each of these compounds at 0, 10 or 15 days following bud induction. The results obtained in our assays indicate that ethylene has a significant influence on tomato organogenesis. Concentrations of ethylene lower than the optimum (according to genotype) at the beginning of the culture may decrease the percentage of explants with buds (B), produce a delay in their appearance, or indeed inhibit bud formation. This was observed in S. pennellii and the F1 explants cultured on media with SN (5.8-58.0 ¿M) as well as in the F1 explants cultured on medium with 21.0 ¿M CoCl 2. The percentage of explants with shoots (R) and the mean number of shoots per explant with shoots (PR) also diminished in media that contained SN. Shoots isolated from these explants were less developed compared to those isolated from control explants. On the other hand, ethylene supplementation may contribute to enhancing shoot development. The number of isolable shoots from S. pennellii explants doubled in media with ACC (9.8-98.0 ¿M). Shoots isolated from explants treated with ethylene releasing compounds showed a higher number of nodes when ACC and Ethephon were added at 10 days (in F1 explants) or at 15 days (in S. pennellii) after the beginning of culture. Thus, the importance of studying not only the concentration but also the timing of the application of regulators when developing regeneration protocols has been made manifest. An excess of ethylene supplementation may produce an inhibitory effect, as was observed when using Ethephon (17.2-69.0 ¿M). These results show the involvement of ethylene in tomato organogenesis and lead us to believe that ethylene supplementation may contribute to enhancing regeneration and shoot development in tomato. © 2012 Springer Science+Business Media B.V.Carlos Trujillo has a predoctoral fellowship from the Spanish 'Ministerio de Educacion y Ciencia'. This work has been funded by Universitat Politecnica de Valencia (PAID 05-10). The technical assistance of N. 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Adalimumab, etanercept and ustekinumab for treating plaque psoriasis in children and young people: systematic review and economic evaluation

Background: Psoriasis is a chronic inflammatory disease that predominantly affects the skin. Adalimumab (HUMIRA®, AbbVie, Maidenhead, UK), etanercept (Enbrel®, Pfizer, New York, NY, USA) and ustekinumab (STELARA®, Janssen Biotech, Inc., Titusville, NJ, USA) are the three biological treatments currently licensed for psoriasis in children. Objective: To determine the clinical effectiveness and cost-effectiveness of adalimumab, etanercept and ustekinumab within their respective licensed indications for the treatment of plaque psoriasis in children and young people. Data sources: Searches of the literature and regulatory sources, contact with European psoriasis registries, company submissions and clinical study reports from manufacturers, and previous National Institute for Health and Care Excellence (NICE) technology appraisal documentation. Review methods: Included studies were summarised and subjected to detailed critical appraisal. A network meta-analysis incorporating adult data was developed to connect the effectiveness data in children and young people and populate a de novo decision-analytic model. The model estimated the cost-effectiveness of adalimumab, etanercept and ustekinumab compared with each other and with either methotrexate or best supportive care (BSC), depending on the position of the intervention in the management pathway. Results: Of the 2386 non-duplicate records identified, nine studies (one randomised controlled trial for each drug plus six observational studies) were included in the review of clinical effectiveness and safety. Etanercept and ustekinumab resulted in significantly greater improvements in psoriasis symptoms than placebo at 12 weeks’ follow-up. The magnitude and persistence of the effects beyond 12 weeks is less certain. Adalimumab resulted in significantly greater improvements in psoriasis symptoms than methotrexate for some but not all measures at 16 weeks. Quality-of-life benefits were inconsistent across different measures. There was limited evidence of excess short-term adverse events; however, the possibility of rare events cannot be excluded. The majority of the incremental cost-effectiveness ratios for the use of biologics in children and young people exceeded NICE’s usual threshold for cost-effectiveness and were reduced significantly only when combined assumptions that align with those made in the management of psoriasis in adults were adopted. Limitations: The clinical evidence base for short- and long-term outcomes was limited in terms of total participant numbers, length of follow-up and the absence of young children. Conclusions: The paucity of clinical and economic evidence to inform the cost-effectiveness of biological treatments in children and young people imposed a number of strong assumptions and uncertainties. Health-related quality-of-life (HRQoL) gains associated with treatment and the number of hospitalisations in children and young people are areas of considerable uncertainty. The findings suggest that biological treatments may not be cost-effective for the management of psoriasis in children and young people at a willingness-to-pay threshold of £30,000 per quality-adjusted life-year, unless a number of strong assumptions about HRQoL and the costs of BSC are combined. Registry data on biological treatments would help determine safety, patterns of treatment switching, impact on comorbidities and long-term withdrawal rates. Further research is also needed into the resource use and costs associated with BSC. Adequately powered randomised controlled trials (including comparisons against placebo) could substantially reduce the uncertainty surrounding the effectiveness of biological treatments in biologic-experienced populations of children and young people, particularly in younger children. Such trials should establish the impact of biological therapies on HRQoL in this population, ideally by collecting direct estimates of EuroQol-5 Dimensions for Youth (EQ-5D-Y) utilities. Study registration: This study is registered as PROSPERO CRD42016039494. Funding: The National Institute for Health Research Health Technology Assessment programme

Canagliflozin, dapagliflozin and empagliflozin monotherapy for treating type 2 diabetes: systematic review and economic evaluation

Background: Most people with type 2 diabetes are overweight, so initial treatment is aimed at reducing weight and increasing physical activity. Even modest weight loss can improve control of blood glucose. If drug treatment is necessary, the drug of first choice is metformin. However, some people cannot tolerate metformin, which causes diarrhoea in about 10%, and it cannot be used in people with renal impairment. This review appraises three of the newest class of drugs for monotherapy when metformin cannot be used, the sodium–glucose co-transporter 2 (SGLT2) inhibitors. Objective: To review the clinical effectiveness and cost-effectiveness of dapagliflozin (Farxiga, Bristol-Myers Squibb, Luton, UK), canagliflozin (Invokana, Janssen, High Wycombe, UK) and empagliflozin (Jardiance, Merck & Co., Darmstadt, Germany), in monotherapy in people who cannot take metformin. Sources: MEDLINE (1946 to February 2015) and EMBASE (1974 to February 2015) for randomised controlled trials lasting 24 weeks or more. For adverse events, a wider range of studies was used. Three manufacturers provided submissions. Methods: Systematic review and economic evaluation. A network meta-analysis was carried out involving the three SGLT2 inhibitors and key comparators. Critical appraisal of submissions from three manufacturers. Results: We included three trials of dapagliflozin and two each for canagliflozin and empagliflozin. The trials were of good quality. The canagliflozin and dapagliflozin trials compared them with placebo, but the two empagliflozin trials included active comparators. All three drugs were shown to be effective in improving glycaemic control, promoting weight loss and lowering blood pressure (BP). Limitations: There were no head-to-head trials of the different flozins, and no long-term data on cardiovascular outcomes in this group of patients. Most trials were against placebo. The trials were done in patient groups that were not always comparable, for example in baseline glycated haemoglobin or body mass index. Data on elderly patients were lacking. Conclusions: Dapagliflozin, canagliflozin and empagliflozin are effective in improving glycaemic control, with added benefits of some reductions in BP and weight. Adverse effects are urinary and genital tract infections in a small proportion of users. In monotherapy, the three drugs do not appear cost-effective compared with gliclazide or pioglitazone, but may be competitive against sitagliptin (Januvia, Boehringer Ingelheim, Bracknell, UK). Funding: The National Institute for Health Research Health Technology Assessment programme