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Paul M. Loadman Christopher R. Calabrese 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2001,764(1-2)
The quinoid anthracycline-related anti-cancer agents represent an important group of anti-tumour drugs with a wide spectrum of activity. We review here some of the separation techniques used for the analysis of anthracyclines and related compounds. In this review we have covered a range of compounds from the early anthracycline antibiotics such as doxorubicin to the more recent anthracenediones and anthrapyrazoles such as mitoxantrone and losoxantrone, respectively. We also include novel compounds such as AQ4N and C1311, both awaiting clinical trial. Separations of the anthraquinone related anti-cancer agents are predominantly by HPLC. These separation techniques have been used for a variety of applications including drug stability, protein binding and therapeutic drug monitoring as well as detailed pharmacokinetic and metabolic studies. Pharmacokinetics, and therefore drug analysis, plays a central role in both the development of new agents and also leads to a better understanding of clinically established agents in this class. Sample preparation and extraction methods including solid-phase and liquid–liquid extraction have also been highlighted. Many anthraquinone related compounds are highly coloured and fluoresce. They are suitable for a range of detection methods including UV–Vis, electrochemical and fluorescence. The methods described are used for sometimes complex separations that are needed for the evaluation of such compounds in biological samples. 相似文献
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Ronald L. Calabrese 《Current biology : CB》2012,22(18):R803-R804
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A novel, single-step, chromatographic procedure for the purification of ceruloplasmin is described. The procedure consists of a single chromatographic step, leading in approximately 5 hours from 2 liters of plasma to an electrophoretically homogeneous ceruloplasmin preparation which exhibits different spectroscopic properties with respect to the protein obtained with more lengthy, currently available procedures. The method is suitable for either small or large scale purification from various vertebrate plasma. 相似文献
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A Galtieri G Natoli A Lania L Calabrese 《Comparative biochemistry and physiology. B, Comparative biochemistry》1986,83(3):555-559
A Cu,Zn superoxide dismutase was purified for the first time from an elasmobranch species (Prionace glauca) and showed the following differences with respect to other animal superoxide dismutases. The enzyme displays a low isoelectric point. The enzyme activity is unusually independent of ionic strength. The isolated enzyme has 30% of its copper in the reduced state. 相似文献
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Jonathan Lachal Massimiliano Orri Jordan Sibeoni Marie Rose Moro Anne Revah-Levy 《PloS one》2015,10(5)
BackgroundYouth suicide is a major public health issue throughout the world. Numerous theoretical models have been proposed to improve our understanding of suicidal behaviours, but medical science has struggled to integrate all the complex aspects of this question. The aim of this review is to synthesise the views of suicidal adolescents and young adults, their parents, and their healthcare professionals on the topics of suicidal behaviour and management of those who have attempted suicide, in order to propose new pathways of care, closer to the issues and expectations of each group.ConclusionThe violence of the message of a suicidal act and the fears associated with death lead to incomprehension and interfere with the capacity for empathy of both family members and professionals. The issue in treatment is to be able to witness this violence so that the patient feels understood and heard, and thus to limit recurrences. 相似文献
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Matt J. Keeling Edward M. Hill Erin E. Gorsich Bridget Penman Glen Guyver-Fletcher Alex Holmes Trystan Leng Hector McKimm Massimiliano Tamborrino Louise Dyson Michael J. Tildesley 《PLoS computational biology》2021,17(1)
Efforts to suppress transmission of SARS-CoV-2 in the UK have seen non-pharmaceutical interventions being invoked. The most severe measures to date include all restaurants, pubs and cafes being ordered to close on 20th March, followed by a “stay at home” order on the 23rd March and the closure of all non-essential retail outlets for an indefinite period. Government agencies are presently analysing how best to develop an exit strategy from these measures and to determine how the epidemic may progress once measures are lifted. Mathematical models are currently providing short and long term forecasts regarding the future course of the COVID-19 outbreak in the UK to support evidence-based policymaking. We present a deterministic, age-structured transmission model that uses real-time data on confirmed cases requiring hospital care and mortality to provide up-to-date predictions on epidemic spread in ten regions of the UK. The model captures a range of age-dependent heterogeneities, reduced transmission from asymptomatic infections and produces a good fit to the key epidemic features over time. We simulated a suite of scenarios to assess the impact of differing approaches to relaxing social distancing measures from 7th May 2020 on the estimated number of patients requiring inpatient and critical care treatment, and deaths. With regard to future epidemic outcomes, we investigated the impact of reducing compliance, ongoing shielding of elder age groups, reapplying stringent social distancing measures using region based triggers and the role of asymptomatic transmission. We find that significant relaxation of social distancing measures from 7th May onwards can lead to a rapid resurgence of COVID-19 disease and the health system being quickly overwhelmed by a sizeable, second epidemic wave. In all considered age-shielding based strategies, we projected serious demand on critical care resources during the course of the pandemic. The reintroduction and release of strict measures on a regional basis, based on ICU bed occupancy, results in a long epidemic tail, until the second half of 2021, but ensures that the health service is protected by reintroducing social distancing measures for all individuals in a region when required. Our work confirms the effectiveness of stringent non-pharmaceutical measures in March 2020 to suppress the epidemic. It also provides strong evidence to support the need for a cautious, measured approach to relaxation of lockdown measures, to protect the most vulnerable members of society and support the health service through subduing demand on hospital beds, in particular bed occupancy in intensive care units. 相似文献
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In this paper, we investigate the dynamic aspects of the molecular recognition between a small molecule ligand and a flat, exposed protein surface, representing a typical target in the development of protein-protein interaction inhibitors. Specifically, we analyze the complex between the protein Fibroblast Growth Factor 2 (FGF2) and a recently discovered small molecule inhibitor, labeled sm27 for which the binding site and the residues mainly involved in small molecule recognition have been previously characterized. We have approached this problem using microsecond MD simulations and NMR-based characterizations of the dynamics of the apo and holo states of the system. Using direct combination and cross-validation of the results of the two techniques, we select the set of conformational states that best recapitulate the principal dynamic and structural properties of the complex. We then use this information to generate a multi-structure representation of the sm27-FGF2 interaction. We propose this kind of representation and approach as a useful tool in particular for the characterization of systems where the mutual dynamic influence between the interacting partners is expected to play an important role. The results presented can also be used to generate new rules for the rational expansion of the chemical diversity space of FGF2 inhibitors. 相似文献
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