127 research outputs found

    High affinity immobilization of proteins using the CrAsH/TC tag

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    Protein microarrays represent important tools for biomedical analysis. We have recently described the use of the biarsenical-tetracysteine (TC) tag for the preparation of protein microarrays. The unique feature of this tag enables the site-specific immobilization of TC-containing proteins on biarsenical-modified surfaces, resulting in a fluorescence enhancement that allows the direct quantification of the immobilized proteins. Moreover, the reversibility of the binding upon incubation with large quantities of thiols permits the detachment of the proteins from the surface, thereby enabling recovery of the substrate to extend the life time of the slide. Herein, we describe our recent results that further extend the applicability of the CrAsH/TC tag to the fabrication of biochips. With this aim, the immobilization of proteins on surfaces has been investigated using two different spacers and two TC tags, the minimal TC sequence (CCPGCC) and an optimized motif (FLNCCPGCCMEP). While the minimal peptide motif enables a rapid recycling of the slide, the optimized TC sequence reveals an increased affinity due to its greater resistance to displacement by thiols. Moreover, the developed methodology was applied to the immobilization of proteins via on-chip ligation of recombinant protein thioesters

    Male breast cancer, clinical presentation, diagnosis and treatment: Twenty years of experience in our Breast Unit

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    BACKGROUND: The male breast cancer (MBC) is a rare and represents less than 1% of all malignancies in men and only 1% of all breast cancers incident. We illustrate the experience of our team about the clinico-pathological characteristics, treatment and prognostic factors of patients treated over a period of twenty years . RESULTS: Forty-seven patients were collected 1995-2014 at the Breast Unit of the Hospital of Terni, Italy. The average age was 67 years and the median time to diagnosis from the onset of symptoms was 16 months. The main clinical complaint was sub areolar swelling in 36, 76% of cases. Most patients have come to our attention with advanced disease. The histology of about ninety percent of the tumors were invasive ductal carcinoma. Management consisted mainly of radical mastectomy; followed by adjuvant radiotherapy and hormonal therapy with or without chemotherapy. The median follow-up was 38 months. The evolution has been characterized by local recurrences; in eight cases (17% of all patients). Metastasis occurred in 15 cases (32% of all patients). The site of bone metastases was in eight cases; lung in four cases; liver in three cases; liver and skin in one case and pleura and skin in one case. CONCLUSION: The male breast cancer has many similarities to breast cancer in women, but there are distinct functions that need to be appreciated. Future research for a better understanding of the disease should provide a better account of genetic and epigenetic characteristics of these forms; but, above all, epidemiological and biological cohorts numerically more consistent

    Virtual patients design and its effect on clinical reasoning and student experience : a protocol for a randomised factorial multi-centre study

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    Background Virtual Patients (VPs) are web-based representations of realistic clinical cases. They are proposed as being an optimal method for teaching clinical reasoning skills. International standards exist which define precisely what constitutes a VP. There are multiple design possibilities for VPs, however there is little formal evidence to support individual design features. The purpose of this trial is to explore the effect of two different potentially important design features on clinical reasoning skills and the student experience. These are the branching case pathways (present or absent) and structured clinical reasoning feedback (present or absent). Methods/Design This is a multi-centre randomised 2x2 factorial design study evaluating two independent variables of VP design, branching (present or absent), and structured clinical reasoning feedback (present or absent).The study will be carried out in medical student volunteers in one year group from three university medical schools in the United Kingdom, Warwick, Keele and Birmingham. There are four core musculoskeletal topics. Each case can be designed in four different ways, equating to 16 VPs required for the research. Students will be randomised to four groups, completing the four VP topics in the same order, but with each group exposed to a different VP design sequentially. All students will be exposed to the four designs. Primary outcomes are performance for each case design in a standardized fifteen item clinical reasoning assessment, integrated into each VP, which is identical for each topic. Additionally a 15-item self-reported evaluation is completed for each VP, based on a widely used EViP tool. Student patterns of use of the VPs will be recorded. In one centre, formative clinical and examination performance will be recorded, along with a self reported pre and post-intervention reasoning score, the DTI. Our power calculations indicate a sample size of 112 is required for both primary outcomes

    Why is TeV-scale a geometric mean of neutrino mass and GUT-scale?

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    Among three typical energy scales, a neutrino mass scale (mνm_\nu\sim 0.1 eV), a GUT scale (MGUT1016M_{GUT}\sim 10^{16} GeV), and a TeV-scale (MNP1M_{NP}\sim 1 TeV), there is a fascinating relation of MNPmνMGUTM_{NP}\simeq \sqrt{m_\nu\cdot M_{GUT}}. The TeV-scale, MNPM_{NP}, is a new physics scale beyond the standard model which is regarded as supersymmetry in this letter. We suggest a simple supersymmetric neutrinophilic Higgs doublet model, which realizes the above relation dynamically as well as the suitable mνm_\nu through a tiny vacuum expectation value of neutrinophilic Higgs without additional scales other than MNPM_{NP} and MGUTM_{GUT}. A gauge coupling unification, which is an excellent feature in the supersymmetric standard model, is preserved automatically in this setup.Comment: 7 page

    Discovery and Creation: Alternative Theories of Entrepreneurial Action

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    As oportunidades empreendedoras existem, independentemente, das percepções dos empreendedores, esperando apenas para serem descobertas? Ou, estas oportunidades são criadas pelas ações dos empreendedores? Duas teorias, internamente, consistentes com as oportunidades empreendedoras são: teoria da criação e teoria da descoberta- as quais serão descritas. Enquanto, será sempre possível, descrever a formação de uma oportunidade particular, como exemplo, de um processo da descoberta ou da criação de oportunidade, estas duas teorias têm implicações importantes para a eficácia de uma variedade ampla de ações empreendedoras em contextos diferentes. As implicações destas teorias para sete destas ações serão descritas, acompanhadas de uma discussão sobre algumas das implicações teóricas mais amplas destas duas teorias para os campos do empreendimento e do gerenciamento estratégico
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