1,427 research outputs found

    The impact of cell crowding and active cell movement on vascular tumour growth

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    A multiscale model for vascular tumour growth is presented which includes systems of ordinary differential equations for the cell cycle and regulation of apoptosis in individual cells, coupled to partial differential equations for the spatio-temporal dynamics of nutrient and key signalling chemicals. Furthermore, these subcellular and tissue layers are incorporated into a cellular automaton framework for cancerous and normal tissue with an embedded vascular network. The model is the extension of previous work and includes novel features such as cell movement and contact inhibition. We presented a detailed simulation study of the effects of these additions on the invasive behaviour of tumour cells and the tumour's response to chemotherapy. In particular, we find that cell movement alone increases the rate of tumour growth and expansion, but that increasing the tumour cell carrying capacity leads to the formation of less invasive dense hypoxic tumours containing fewer tumour cells. However, when an increased carrying capacity is combined with significant tumour cell movement, the tumour grows and spreads more rapidly, accompanied by large spatio-temporal fluctuations in hypoxia, and hence in the number of quiescent cells. Since, in the model, hypoxic/quiescent cells produce VEGF which stimulates vascular adaptation, such fluctuations can dramatically affect drug delivery and the degree of success of chemotherapy

    Long-term glycaemic control with metformin– sulphonylurea–pioglitazone triple therapy in PROactive (PROactive 17)

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    peer reviewedAims We assessed the long-term glycaemic effects and the safety profile of triple therapy with the addition of pioglitazone vs. placebo in patients with Type 2 diabetes treated with combined metformin–sulphonylurea therapy in the PROspective pioglitAzone Clinical Trial In macroVascular Events (PROactive). Methods In a post-hoc analysis, we identified patients treated with metformin plus sulphonylurea combination therapy and not receiving insulin at baseline (n = 1314). In those patients, we compared the effects of pioglitazone (force-titrated to 45 mg⁄ day, n = 654) vs. placebo (n = 660) on glycated haemoglobin (HbA1c) reduction, concomitant changes in medications and initiation of permanent insulin use (defined as daily insulin use for a period of ‡ 90 days or ongoing use at death ⁄ final visit). Results Significantly greater reductions in HbA1c and greater proportions of patients with HbA1c at target were noted with pioglitazone vs, placebo, despite a decrease in the use of other oral glucose-lowering agents. Therewas an approximate twofold increase in progression to permanent insulin use in the placebo group vs. the pioglitazone group: 31.1 vs. 16.1%, respectively, when added to combination therapy. The overall safety of themetformin–sulphonylurea–pioglitazone triple therapy was good. Conclusions Intensifying an existing dual oral therapy regimen to a triple oral regimen by adding pioglitazone to the classical metformin–sulphonylurea combination resulted in sustained improvements in glycaemic control and reduced progression to insulin therapy. The advantages and disadvantages of adding pioglitazone instead of adding basal insulin should be assessed further

    Self-management of rheumatic diseases: State of the art and future perspectives

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    Self-management interventions are patient-centred and designed to foster active participation of patients in order to promote well-being and to manage symptoms. Over the past two decades, the role of self-management in chronic diseases has gained momentum. Self-management programmes are now acknowledged as a key element of quality care. New modes of delivery allow greater access to information and are tailored to address patient needs. This systematic review presents data from clinical studies of self-management over the past decade, summarises the evidence for programme effectiveness, and suggests future research directions

    (+)-Hexacyclinol

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    A sample of the title compound [systematic name: (1aS,2aS,3S,5aS,6aS,7R,7aS,7bS,8R,8aS,10R)-7-hydr­oxy-3-(1-meth­oxy-1-methyl­ethyl)-10-(2-methyl-1-propen­yl)-1a,5a,6a,7,7a,7b,8,8a-octa­hydro-2H-8,2a-(epoxy­methano)phenanthro[2,3-b:6,7-b′]bis­oxirene-2,5(3H)-dione], C23H28O7, was generated by enanti­oselective synthesis. There are three mol­ecules of the compound in the crystallographic asymmetric unit. Hydrogen bonding between alcohol H atoms and keto groups of adjacent mol­ecules appears to stabilize the structure. The compound is enanti­omerically pure but the absolute configuration could not be determined directly in this study. Accordingly, the illustrated configuration was assigned on the basis of the nature of the chiral nonracemic precursor used in the synthesis

    Computer-controlled apparatus for automated development of continuous flow methods

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    An automated apparatus to assist in the development of analytical continuous flow methods is described. The system is capable of controlling and monitoring a variety of pumps, valves, and detectors through an IBM PC-AT compatible computer. System components consist of two types of peristaltic pumps (including a multiple pump unit), syringe pumps, electrically and pneumatically actuated valves, and an assortment of spectrophotometric and electrochemical detectors. Details of the interface circuitry are given where appropriate. To demonstrate the utility of the system, an automatically generated response surface is presented for the flow injection determination of iron(II) by its reaction with 1,10-phenanthroline

    12-Eth­oxy-2,3,8,9-tetra­methoxy­benzo[c]phenanthridine dichloro­methane solvate

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    The title compound, C23H23NO5·CH2Cl2, was obtained via the alkyl­ation of the 12-hydr­oxy-2,3,8,9-tetra­methoxy­benzo[c]phenanthridine salt. The benzo[c]phenanthridine ring system is essentially planar, with a mean out-of-plane deviation of 0.026 Å. A dicloromethane mol­ecule of solvation is present and located between the sheets of phenanthridine mol­ecules, preventing any significant inter­molecular hydrogen-bonding or π–π inter­actions

    Nitrogen Leaching from Cattle, Sheep and Deer Grazed Pastures in New Zealand

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    The impacts of intensified grazing in New Zealand are being reflected in declining quality of groundwater, streams and lake water. Manipulation of ratios of grazing animal species may be one way farmers can reduce nitrogen (N) emissions to ground water. The present research quantifies nitrate and ammonium leaching losses from rotationally grazed sheep, cattle and deer pastures in a common environment

    Pain associated with pressure injury: A qualitative study of community-based, home-dwelling individuals

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    © 2017 John Wiley & Sons Ltd. Aims: The aim of this study was to provide deep insights into the pain associated with pressure injuries in home-dwelling individuals using narrative accounts. Background: Pressure injuries or pressure ulcers are burdensome and costly. Prevalence data, surveys and systematic reviews demonstrate that pain associated with pressure injury is widespread, but voices of home-dwelling patients have remained largely unheard. Design: Concurrent mixed methods case study of a UK community of approximately 50,000 adults. Methods: Qualitative interviews, conducted in 2016, of 12 home-dwelling adult participants with a current pressure injury (n = 10), or a recently healed pressure injury (n = 2). Findings: Pain had an adverse impact on activities of daily living, mobility and sleep. Participants described days that were clouded in pain; a pain they felt was poorly understood and often out of control. Thematic content analysis revealed two major themes; these are: Poorly controlled pain: “I just want the pain to go away”; and, Uncertainty for the future: “it almost seems insurmountable.”. Conclusion: Findings of our study support the need to develop an appropriate assessment tool for pressure injury patients in the community to enable healthcare professionals and patients to recognize and manage pressure injury-related pain effectively

    Health service provision and the use of pressure-redistributing devices: mixed methods study of community dwelling individuals with pressure injuries

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    © 2017 Informa UK Limited, trading as Taylor & Francis Group. Background: Health care within the home setting is a vital and growing component of pressure injury (PI) prevention and management. Objectives: To describe the use of health services and pressure-redistributing devices in community dwelling patients with PI’s. Design: Mixed-methods collective case study of a defined, diverse geographic postcode area in the United Kingdom. Methods: Quantitative retrospective analysis of electronic and paper medical records of adult PI patients from 2015 district nursing reports. Qualitative semi-structured interviews of community dwelling adult patients receiving, or received, treatment for PI in 2016. Results: Mandatory reports (n = 103) revealed that 90 patients were supplied with a variety of pressure-redistributing devices but only one-third of patients used the equipment as recommended. Qualitative interviews (n = 12), reported to COREQ guidelines, revealed that patients felt reliant on community health services, and were concerned about the consistency of their care. Conclusions: Authentic patient involvement is required to provide care and interventions that are acceptable to PI patients and can be incorporated into self-care strategies and effectively monitored
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