28 resultados para Isabella I, Queen of Spain, 1451-1504
Resumo:
PURPOSE:
The protease inhibitor bortezomib attenuates the action of NF-κB and has shown preclinical activity alone and in combination with chemotherapy.
DESIGN:
A Phase I dose-escalation study was performed administering bortezomib (0.7, 1.0, 1.3 and 1.6 mg m(-2) on days 1 and 8 from cycle 2 onwards) in combination with Epirubicin 50 mg m(-2) intravenously on day 1, Carboplatin AUC 5 day 1 and Capecitabine 625 mg m(-2) BD days 1-21 every 21 days (VECarboX regimen), in patients with advanced oesophagogastric adenocarcinoma. The primary objective was to define the maximum tolerated dose (MTD) of Bortezomib when combined with ECarboX.
RESULTS:
18 patients received bortezomib 0.7 (n = 6), 1.0 (n = 3), 1.3 (n = 6) and 1.6 mg m(-2) (n = 3) and a protocol amendment reducing the capecitabine dose to 500 mg m(-2) BD was enacted due to myelotoxicity. Common treatment-related non-haematological adverse events of any grade were fatigue (83.3 %), anorexia (55.6 %), constipation (55.6 %) and nausea (55.6 %). Common Grade 3/4 haematological toxicities were neutropenia (77.8 %) and thrombocytopenia (44.4 %). Objective responses were achieved in 6 patients (33.3 %) and a further 5 patients (27.8 %) had stable disease for >8 weeks.
CONCLUSIONS:
The addition of Bortezomib to ECarboX is well tolerated and response rates are comparable with standard chemotherapy.
Resumo:
Bacteroides fragilis is an opportunistic pathogen which can cause life threatening infections in humans and animals. The ability to adhere to components of the extracellular matrix, including collagen, is related to bacterial host colonisation. Collagen Far Western analysis of the B. fragilis outer membrane protein (OMP) fraction revealed the presence two collagen adhesin bands of ∼31 and ∼34 kDa. The collagen adhesins in the OMP fraction were separated and isolated by two-dimensional SDS-PAGE and also purified by collagen affinity chromatography. The collagen binding proteins isolated by both these independent methods were subjected to tandem mass spectroscopy for peptide identification and matched to a single hypothetical protein encoded by B. fragilis NCTC 9343 (BF0586), conserved in YCH46 (BF0662) and 638R (BF0633) and which is designated in this study as cbp1 (collagen binding protein). Functionality of the protein was confirmed by targeted insertional mutagenesis of the cbp1 gene in B. fragilis GSH18 which resulted in the specific loss of both the ∼31 kDa and the ∼34 kDa adhesin bands. Purified his-tagged Cbp1, expressed in a B. fragilis wild-type and a glycosylation deficient mutant, confirmed that the cbp1 gene encoded the observed collagen adhesin, and showed that the 34 kDa band represents a glycosylated version of the ∼31 kDa protein. Glycosylation did not appear to be required for binding collagen. This study is the first to report the presence of collagen type I adhesin proteins in B. fragilis and to functionally identify a gene encoding a collagen binding protein. © 2014 Galvão et al.
Resumo:
Background: RAS is mutated (RASMT) in ~55% of mCRC, and phase III studies have shown that patients harbouring RAS mutations do not benefit from anti-EGFR MoAbs. In addition, ~50% of RAS Wild Type (RASWT) will not benefit from the addition of an EGFR MoAb to standard chemotherapy. Hence, novel treatment strategies are urgently needed for RASMT and > 50% of RASWT mCRC patients. c-MET is overexpressed in ~50-60%, amplified in ~2-3% and mutated in ~3-5% of mCRC. Recent preclinical studies have shown that c-MET is an important mediator of resistance to MEK inhibitors (i) in RASMT mCRC, and that combined MEKi/METi resulted in synergistic reduction in tumour growth in RASMT xenograft models (1). A number of recent studies have highlighted the role of c-MET in mediating primary/secondary resistance to anti-EGFR MoAbs in mCRC, suggesting that patient with RASWT tumours with aberrant c-MET (RASWT/c-MET+) may benefit from anti-c-MET targeted therapies (2). These preclinical data supported the further clinical evaluation of combined MEKi/METi treatment in RASMT and RASWT CRC patients with aberrant c-MET signalling (overexpression, amplification or mutation; RASWT/c-MET+). Methods: MErCuRIC1 is a phase I combination study of METi crizotinib with MEKi PD-0325901. The dose escalation phase, utilizing a rolling six design, recruits 12-24 patients with advanced solid tumours and aims to assess safety/toxicity of combination, recommended phase II (RPII) dose, pharmacokinetics (PK) and pharmacodynamics (PD) (pERK1/2 in PBMC and tumour; soluble c-MET). In the dose expansion phase an additional 30-42 RASMT and RASWT/c-MET mCRC patients with biopsiable disease will be treated at the RPII dose to further evaluate safety, PK, PD and treatment response. In the dose expansion phase additional biopsy and blood samples will be obtained to define mechanisms of response/resistance to crizotinib/PD-0325901 therapy. Enrolment into the dose escalation phase began in December 2014 with cohort 1 still ongoing. EudraCT registry number: 2014-000463-40. (1) Van Schaeybroeck S et al. Cell Reports 2014;7(6):1940-55; (2) Bardelli A et al. Cancer Discov 2013;3(6):658-73. Clinical trial information: 2014-000463-40.
Resumo:
Our earliest version of the Thomas Rymer story is the medieval romance Thomas off Ersseldoune (c.1430). There is a four hundred year lacuna before the ballad “Thomas Rymer”, our next surviving version, is recorded in the early 1800s. In the intervening time the narrative changed very little but the dynamic of the piece, radically. The romance transformed into the highly subversive ballad, “Thomas Rymer”. Central to this transformation is the reconceptualization of the romance's heroine. Referred to simply as the “lufly lady” and caught between her husband, the fay King, and a mere mortal, Thomas, she becomes in the ballad the powerful Queen of the Fairies. The ballad is structured around a series of revelations in which the enigmatic Queen assumes the roles of Eve and Mary, and finally Christ Himself. I will explore the implications of this extraordinary ballad. Moreover, I suggest that it is Queen Elizabeth herself who, ironically, enables the heroine's transformation. “Ironically” because it appears that it was Elizabeth's own restrictions, designed to suppress heretical, seditious or radical literature, which forced Thomas off Ersseldoune (and many other romances which employed religious imagery or figures) out of the written domain and into the oral tradition. And yet, it is Elizabeth who, in creating the image of herself as a female prince, as the Faerie Queen, inspires a new literary vocabulary designed to describe female executive power, without which it would have been impossible to imagine a figure such as the ballad's Queen of the Fairies.
Resumo:
Mitochondrial complex I (NADH: ubiquinone oxidoreductase) undergoes reversible deactivation upon incubation at 30-37 degrees C. The active/deactive transition could play an important role in the regulation of complex I activity. It has been suggested recently that complex I may become modified by S-nitrosation under pathological conditions during hypoxia or when the nitric oxide: oxygen ratio increases. Apparently, a specific cysteine becomes accessible to chemical modification only in the deactive form of the enzyme. By selective fluorescence labeling and proteomic analysis, we have identified this residue as cysteine-39 of the mitochondrially encoded ND3 subunit of bovine heart mitochondria. Cysteine-39 is located in a loop connecting the first and second transmembrane helix of this highly hydrophobic subunit. We propose that this loop connects the ND3 subunit of the membrane arm with the PSST subunit of the peripheral arm of complex I, placing it in a region that is known to be critical for the catalytic mechanism of complex I. In fact, mutations in three positions of the loop were previously reported to cause Leigh syndrome with and without dystonia or progressive mitochondrial disease.
Resumo:
Proton pumping respiratory complex I (NADH: ubiquinone oxidoreductase) is a major component of the oxidative phosphorylation system in mitochondria and many bacteria. In mammalian cells it provides 40% of the proton motive force needed to make ATP. Defects in this giant and most complicated membrane-bound enzyme cause numerous human disorders. Yet the mechanism of complex I is still elusive. A group exhibiting redox-linked protonation that is associated with iron-sulfur cluster N2 of complex I has been proposed to act as a central component of the proton pumping machinery. Here we show that a histidine in the 49-kDa subunit that resides near iron-sulfur cluster N2 confers this redox-Bohr effect. Mutating this residue to methionine in complex I from Yarrowia lipolytica resulted in a marked shift of the redox midpoint potential of iron-sulfur cluster N2 to the negative and abolished the redox-Bohr effect. However, the mutation did not significantly affect the catalytic activity of complex I and protons were pumped with an unchanged stoichiometry of 4 H+/2e(-). This finding has significant implications on the discussion about possible proton pumping mechanism for complex I.
Resumo:
PURPOSE The appropriate selection of patients for early clinical trials presents a major challenge. Previous analyses focusing on this problem were limited by small size and by interpractice heterogeneity. This study aims to define prognostic factors to guide risk-benefit assessments by using a large patient database from multiple phase I trials. PATIENTS AND METHODS Data were collected from 2,182 eligible patients treated in phase I trials between 2005 and 2007 in 14 European institutions. We derived and validated independent prognostic factors for 90-day mortality by using multivariate logistic regression analysis. Results The 90-day mortality was 16.5% with a drug-related death rate of 0.4%. Trial discontinuation within 3 weeks occurred in 14% of patients primarily because of disease progression. Eight different prognostic variables for 90-day mortality were validated: performance status (PS), albumin, lactate dehydrogenase, alkaline phosphatase, number of metastatic sites, clinical tumor growth rate, lymphocytes, and WBC. Two different models of prognostic scores for 90-day mortality were generated by using these factors, including or excluding PS; both achieved specificities of more than 85% and sensitivities of approximately 50% when using a score cutoff of 5 or higher. These models were not superior to the previously published Royal Marsden Hospital score in their ability to predict 90-day mortality. CONCLUSION Patient selection using any of these prognostic scores will reduce non-drug-related 90-day mortality among patients enrolled in phase I trials by 50%. However, this can be achieved only by an overall reduction in recruitment to phase I studies of 20%, more than half of whom would in fact have survived beyond 90 days.
Resumo:
Throughout the reign of Elizabeth I, a steady stream of tracts appeared in English print to vindicate the succession of the most prominent contenders, Mary and James Stuart of Scotland. This article offers a comprehensive account of the polemical battle between the supporters and opponents of the Stuarts, and further identifies various theories of English kingship, most notably the theory of corporate kingship, developed by the Stuart polemicists to defend the Scottish succession. James's accession to the English throne in March 1603 marked the protracted end of the debate over the succession. The article concludes by suggesting that, while powerfully renouncing the opposition to his succession, over the course of his attempt to unify his two kingdoms, James and his supporters ultimately departed from the polemic of corporate kingship, for a more assertive language of kingship by natural and divine law.
Resumo:
In recent years external beam radiotherapy (EBRT) has been proposed as a treatment for the wet form of age-related macular degeneration (AMD) where choroidal neovascularization (CNV) is the hallmark. While the majority of pilot (Phase I) studies have reported encouraging results, a few have found no benefit, i.e. EBRT was not found to result in either improvement or stabilization of visual acuity of the treated eye. The natural history of visual loss in untreated CNV of AMD is highly variable. Loss of vision is influenced mainly by the presenting acuity, and size and composition of the lesion, and to a lesser extent by a variety of other factors. Thus the variable outcome reported by the small Phase I studies of EBRT published to date may simply reflect the variation in baseline factors. We therefore obtained information on 409 patients treated with EBRT from eight independent centres, which included details of visual acuity at baseline and at subsequent follow-up visits. Analysis of the data showed that 22.5% and 14.9% of EBRT-treated eyes developed moderate and severe loss of vision, respectively, during an average follow-up of 13 months. Initial visual acuity, which explained 20.5% of the variation in visual loss, was the most important baseline factor studied. Statistically significant differences in loss of vision were observed between centres, after considering the effects of case mix factors. Comparisons with historical data suggested that while moderate visual loss was similar to that of the natural history of the disease, the likelihood of suffering severe visual loss was halved. However, the benefit in terms of maintained/improved vision in the treated eye was modest.
Resumo:
PURPOSE: We conducted a phase I/II clinical trial to determine the safety and feasibility of combining vorinostat with 5-fluorouracil (5-FU) in patients with metastatic colorectal cancer (mCRC) and elevated intratumoral thymidylate synthase (TS).
METHODS: Patients with mCRC who had failed all standard therapeutic options were eligible. Intratumoral TS mRNA expression and peripheral blood mononuclear cell (PBMC) histone acetylation were measured before and after 6 consecutive days of vorinostat treatment at 400 mg PO daily. 5-FU/LV were given on days 6 and 7 and repeated every 2 weeks, along with continuous daily vorinostat. Dose escalation occurred in cohorts of three to six patients.
RESULTS: Ten patients were enrolled. Three dose levels were explored in the phase I portion of the study. Two dose-limiting toxicities (DLTs) were observed at the starting dose level, which resulted in dose de-escalation to levels -1 and -2. Given the occurrence of two DLTs at each of the dose levels, we were unable to establish a maximum tolerated dose (MTD). Two patients achieved significant disease stabilization for 4 and 6 months. Grade 3 and 4 toxicities included fatigue, thrombocytopenia and mucositis. Intratumoral TS downregulation > or = 50% was observed in one patient only. Acetylation of histone 3 was observed in PBMCs following vorinostat treatment.
CONCLUSIONS: The study failed to establish a MTD and was terminated. The presence of PBMC histone acetylation indicates biological activity of vorinostat, however, consistent reductions in intratumoral TS mRNA were not observed. Alternate vorinostat dose-scheduling may alleviate the toxicity and achieve optimal TS downregulation.