3,068 research outputs found

    Local electronic structure of the peptide bond probed by resonant inelastic soft X-ray scattering.

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    The local valence orbital structure of solid glycine, diglycine, and triglycine is studied using soft X-ray emission spectroscopy (XES), resonant inelastic soft X-ray scattering (RIXS) maps, and spectra calculations based on density-functional theory. Using a building block approach, the contributions of the different functional groups of the peptides are separated. Cuts through the RIXS maps furthermore allow monitoring selective excitations of the amino and peptide functional units, leading to a modification of the currently established assignment of spectral contributions. The results thus paint a new-and-improved picture of the peptide bond, enhance the understanding of larger molecules with peptide bonds, and simplify the investigation of such molecules in aqueous environment

    Intratumoural immunotherapies for unresectable and metastatic melanoma: current status and future perspectives.

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    The emergence of human intratumoural immunotherapy (HIT-IT) is a major step forward in the management of unresectable melanoma. The direct injection of treatments into melanoma lesions can cause cell lysis and induce a local immune response, and might be associated with a systemic immune response. Directly injecting immunotherapies into tumours achieves a high local concentration of immunostimulatory agent while minimising systemic exposure and, as such, HIT-IT agents are associated with lower toxicity than systemic immune checkpoint inhibitors (CPIs), enabling their potential use in combination with other therapies. Consequently, multiple HIT-IT agents, including oncolytic viruses, pattern-recognition receptor agonists, injected CPIs, cytokines and immune glycolipids, are under investigation. This review considers the current clinical development status of HIT-IT agents as monotherapy and in combination with systemic CPIs, and the practical aspects of administering and assessing the response to these agents. The future of HIT-IT probably lies in its use in combination with systemic CPIs; data from Phase 2 trials indicate a synergy between HIT-IT and CPIs. Data also suggest that the addition of HIT-IT to a CPI might generate responses in CPI-refractory tumours, thereby overcoming resistance and addressing a current unmet need in unresectable and metastatic melanoma for treatment options following progression after CPI treatment

    Which medical disciplines diagnose and treat melanoma in Europe in 2019? A survey of experts from melanoma centres in 27 European countries

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    Background and objectives The incidence of melanoma is increasing. This places significant burden on societies to provide efficient cancer care. The European Cancer Organisation recently published the essential requirements for quality melanoma care. The present study is aimed for the first time to roughly estimate the extent to which these requirements have been met in Europe. Materials and methods A web-based survey of experts from melanoma centres in 27 European countries was conducted from 1 February to 1 August 2019. Data on diagnostic techniques, surgical and medical treatment, organization of cancer care and education were collected and correlated with national health and economic indicators and mortality-to-incidence ratio (MIR) as a surrogate for survival. Univariate linear regression analysis was performed to evaluate the correlations. SPSS software was used. Statistical significance was set at P < 0.05. Results The MIR was lower in countries with a high health expenditure per capita and with a higher numbers of general practitioners (GPs) and surgeons (SURG) per million inhabitants. In these countries, GPs and dermatologists (DER) were involved in melanoma detection; high percentage of DER used dermatoscopy and were involved in the follow-up of all melanoma stages; both medical oncologists (ONC) and dermato-oncologists administered systemic treatments; and patients had better access to sentinel lymph node biopsy and were treated within multidisciplinary tumour boards. Conclusion Based on these first estimates, the greater involvement of GPs in melanoma detection; the greater involvement of highly trained DER in dermatoscopy, dermatosurgery, follow-up and the systemic treatment of melanoma; and the provision of ongoing dermato-oncology training for pathologists, SURG, DER and ONC are necessary to provide an optimal melanoma care pathway. A comprehensive analysis of the melanoma care pathway based on clinical melanoma registries will be needed to more accurately evaluate these first insights

    Вемурафениб улучшает выживаемость при меланоме кожи с мутацией BRAF V600E

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    В 40–60% случаев меланомы кожи выявляют мутации онкогена BRAF, следствием которых является конститутивная активация серинтреониновой киназы BRAF и, соответственно, митогенного сигнала по пути MAPK/ERK. Представлены результаты международных рандомизированных исследований I, II, III фазы, в которых оценивали эффективность и токсичность ингибитора RAF-киназной активности вемурафениба (PLX4032, Зелбораф) у больных метастатической меланомой кожи с мутацией BRAF V600E. В исследовании III фазы BRIM3 сравнивали режимы монотерапии вемурафенибом (960 мг перорально 2 раза в сутки — 337 пациентов и дакарбазином (1000 мг/м2 внутривенно каждые 3 нед — 338 пациентов). Первичными точками исследования были общая выживаемость и выживаемость без прогрессирования, вторичными — частота объективного ответа, его длительность, время до развития ответа. Анализ данных после 6 мес наблюдения показал, что применение вемурафениба приводило к относительному снижению риска смерти на 63% и риска прогрессирования заболевания на 74% по сравнению с дакарбазином (р < 0,001 для обоих показателей). Объективный ответ зафиксирован в 48% случаев в группе вемурафениба и в 5% случаев — дакарбазина. Наиболее частыми токсическими эффектами вемурафениба были артралгии, сыпь, общая слабость, алопеция, плоскоклеточная карцинома кожи и кератоакантома, фотосенсибилизация, тошнота, диарея; сокращение дозы, связанное с токсичностью, потребовалось у 38% пациентов. По результатам исследования сделан вывод об эффективности вемурафениба у нелеченных ранее больных метастатической меланомой кожи с мутацией BRAF V600E.40 to 60% of cutaneous melanomas carry mutations in BRAF that lead to constitutive activation of BRAF serine/threonine kinase and downstream signaling through the MAPK/ERK pathway. Phase I and II clinical trials of the BRAF kinase inhibitor vemurafenib (PLX4032, Zelboraf) have shown response rates of more than 50% in patients with metastatic melanoma with the BRAF V600E mutation. In a phase III randomized clinical trial (BRIM-3) comparing vemurafenib with dacarbazine in 675 patients with previously untreated, metastatic melanoma with the BRAF V600E mutation. Patients were randomly assigned to receive either vemurafenib (960 mg orally twice daily) or dacarbazine (1000 mg per square meter of body-surface area intravenously every 3 weeks). Coprimary end points were rates of overall and progression-free survival. Secondary end points included the response rate, response duration, and safety. At 6 months, vemurafenib was associated with a relative reduction of 63% in the risk of death and of 74% in the risk of either death or disease progression, as compared with dacarbazine (p < 0,001 for both comparisons). Response rates were 48% for vemurafenib and 5% for dacarbazine. Common adverse events associated with vemurafenib were arthralgia, rash, fatigue, alopecia, keratoacanthoma or squamous-cell carcinoma, photosensitivity, nausea, and diarrhea; 38% of patients required dose modification because of toxic effects. Vemurafenib produced improved rates of overall and progression-free survival in patients with previously untreated melanoma with the BRAF V600E mutation

    Deep brain stimulation, histone deacetylase inhibitors and glutamatergic drugs rescue resistance to fear extinction in a genetic mouse model

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    Anxiety disorders are characterized by persistent, excessive fear. Therapeutic interventions that reverse deficits in fear extinction represent a tractable approach to treating these disorders. We previously reported that 129S1/SvImJ (S1) mice show no extinction learning following normal fear conditioning. We now demonstrate that weak fear conditioning does permit fear reduction during massed extinction training in S1 mice, but reveals specific deficiency in extinction memory consolidation/retrieval. Rescue of this impaired extinction consolidation/retrieval was achieved with d-cycloserine (N-methly-d-aspartate partial agonist) or MS-275 (histone deacetylase (HDAC) inhibitor), applied after extinction training. We next examined the ability of different drugs and non-pharmacological manipulations to rescue the extreme fear extinction deficit in S1 following normal fear conditioning with the ultimate aim to produce low fear levels in extinction retrieval tests. Results showed that deep brain stimulation (DBS) by applying high frequency stimulation to the nucleus accumbens (ventral striatum) during extinction training, indeed significantly reduced fear during extinction retrieval compared to sham stimulation controls. Rescue of both impaired extinction acquisition and deficient extinction consolidation/retrieval was achieved with prior extinction training administration of valproic acid (a GABAergic enhancer and HDAC inhibitor) or AMN082 [metabotropic glutamate receptor 7 (mGlu7) agonist], while MS-275 or PEPA (AMPA receptor potentiator) failed to affect extinction acquisition in S1 mice. Collectively, these data identify potential beneficial effects of DBS and various drug treatments, including those with HDAC inhibiting or mGlu7 agonism properties, as adjuncts to overcome treatment resistance in exposure-based therapies. This article is part of a Special Issue entitled 'Cognitive Enhancers'. © 2012 Elsevier Ltd. All rights reserved

    The helicase HAGE prevents interferon-a-induced PML expression in ABCB5+ malignant melanoma-initiating cells by promoting the expression of SOCS1

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    The tumour suppressor PML (promyelocytic leukaemia protein) regulates several cellular pathways involving cell growth, apoptosis, differentiation and senescence. PML also has an important role in the regulation of stem cell proliferation and differentiation. Here, we show the involvement of the helicase HAGE in the transcriptional repression of PML expression in ABCB5 + malignant melanoma-initiating cells (ABCB5 + MMICs), a population of cancer stem cells which are responsible for melanoma growth, progression and resistance to drug-based therapy. HAGE prevents PML gene expression by inhibiting the activation of the JAK-STAT (janus kinase-signal transducers and activators of transcription) pathway in a mechanism which implicates the suppressor of cytokine signalling 1 (SOCS1). Knockdown of HAGE led to a significant decrease in SOCS1 protein expression, activation of the JAK-STAT signalling cascade and a consequent increase of PML expression. To confirm that the reduction in SOCS1 expression was dependent on the HAGE helicase activity, we showed that SOCS1, effectively silenced by small interfering RNA, could be rescued by re-introduction of HAGE into cells lacking HAGE. Furthermore, we provide a mechanism by which HAGE promotes SOCS1 mRNA unwinding and protein expression in vitro

    Evaluating the environmental performance of a product/service-system business model for Merino wool next-to-skin garments: The case of Armadillo Merino®

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    Circular business models are often enabled by means of product/service-systems (PSS). The common perception is that such business models have enhanced environmental performance when compared to conventional business models rooted in the linear economy. This article investigates the environmental potential of developing a use-oriented PSS business model for Merino wool t-shirts intended for use by the British Ministry of Defence as an alternative to the present supply system based on synthetic t-shirts purchased from sportswear clothing companies. To conduct the assessment, we apply the life cycle assessment (LCA) methodology to quantify and compare the climate change impacts and impact potentials of the proposed PSS business model and of a reference business model. Results showed that there could be significant contribution of quantifying environmental potential for PSS business models when justifying the transition to a circular economy. However, when adopting LCA methodology for this purpose, the design of the PSS needs to be well thought to overcome some of the identified challenges. The article concludes by making the case that LCA studies can support the definition, design and value creation of the product/service-systems in early development stages

    A hysteresis model with dipole interaction: one more devil-staircase

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    Magnetic properties of 2D systems of magnetic nanoobjects (2D regular lattices of the magnetic nanoparticles or magnetic nanostripes) are considered. The analytical calculation of the hysteresis curve of the system with interaction between nanoobjects is provided. It is shown that during the magnetization reversal system passes through a number of metastable states. The kinetic problem of the magnetization reversal was solved for three models. The following results have been obtained. 1) For 1D system (T=0) with the long-range interaction with the energy proportional to rpr^{-p}, the staircase-like shape of the magnetization curve has self-similar character. The nature of the steps is determined by interplay of the interparticle interaction and coercivity of the single nanoparticle. 2) The influence of the thermal fluctuations on the kinetic process was examined in the framework of the nearest-neighbor interaction model. The thermal fluctuations lead to the additional splitting of the steps on the magnetization curve. 3) The magnetization curve for system with interaction and coercivity dispersion was calculated in mean field approximation. The simple method to experimentally distinguish the influence of interaction and coercivity dispersion on the magnetization curve is suggested.Comment: 22 pages, 8 figure
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