883 research outputs found

    Enhanced kinetic stability of [Pd2L4](4+) cages through ligand substitution

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    There is considerable interest in exploiting metallosupramolecular cages as drug delivery vectors. Recently, we developed a [Pd2L4]4+ cage capable of binding two molecules of cisplatin. Unfortunately, this first generation cage was rapidly decomposed by common biologically relevant nucleophiles. In an effort to improve the kinetic stability of these cage architectures here we report the synthesis of two amino substituted tripyridyl 2,6-bis(pyridin-3-ylethynyl)pyridine (tripy) ligands (with amino groups either in the 2-(2A-tripy) or 3-(3A-tripy) positions of the terminal pyridines) and their respective [Pd2(Ltripy)4]4+ cages. These systems have been characterised by 1H, 13C and DOSY NMR spectroscopies, high resolution electrospray mass spectrometry, elemental analysis and, in one case, by X-ray crystallography. It was established, using model palladium(II) N-heterocyclic carbene (NHC) probe complexes, that the amino substituted compounds were stronger donor ligands than the parent system (2A-tripy > 3A-tripy > tripy). Competition experiments with a range of nucleophiles showed that these substitutions lead to more kinetically robust cage architectures, with [Pd2(2A-tripy)4]4+ proving the most stable. Biological testing on the three ligands and cages against A549 and MDA-MB-231 cell lines showed that only [Pd2(2A-tripy)4]4+ exhibited any appreciable cytotoxicity, with a modest IC50 of 36.4 ± 1.9 μM against the MDA-MB-231 cell line. Unfortunately, the increase in kinetic stability of the [Pd2(Ltripy)4]4+ cages was accompanied by loss of cisplatin-binding ability

    Continuity for s-convex fuzzy processes

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    In a previous paper we introduced the concept of s-convex fuzzy mapping and established some properties. In this work we study the continuity for s-convex fuzzy processes

    Phase I/II study of the deacetylase inhibitor panobinostat after allogeneic stem cell transplantation in patients with high-risk MDS or AML (PANOBEST trial)

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    Maintenance therapy after allogeneic hematopoietic stem cell transplantation (HSCT) for acute myeloid leukemia (AML) or myelodysplastic syndrome (MDS) is conceptually attractive to prevent relapse, but has been hampered by the limited number of suitable anti-leukemic agents. The deacetylase inhibitor (DACi) panobinostat demonstrated moderate anti-leukemic activity in a small subset of patients with advanced AML and high-risk MDS in phase I/II trials.1, 2 It also displays immunomodulatory activity3 that may enhance leukemia-specific cytotoxicity4 and mitigate graft versus host disease (GvHD), but conversely could impair T- and NK cell function.5, 6 We conducted this open-label, multi-center phase I/II trial (NCT01451268) to assess the feasibility and preliminary efficacy of prolonged prophylactic administration of panobinostat after HSCT for AML or MDS. The study protocol was approved by an independent ethics committee and conducted in compliance with the Declaration of Helsinki. All patients provided written informed consent. ..

    Ageing Intensifies the Care Needs of Adults Living with Parkinson ’s Disease and their Carers

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    Parkinson’s disease (PD) is the second most common neurological disorder in Australia typically affecting people over the age of 65. Few studies of people living with Parkinson’s disease have estimated current hours of home support and unmet needs. In addition no studies have been found that estimate hours of unmet need in terms of functioning or care arrangements or examined whether these estimates differ depending on the viewpoints of carers and the people living with PD whom they care for. In 2007, we surveyed the home care support needs of adults diagnosed with Parkinson’s disease in Western Australia (WA). The survey revealed that adults living with Parkinson’s disease prefer, and can be supported with, home care support services in lieu of residential care placement. As expected, required services increased as functioning decreased. In addition, unmet needs were found to be greater for those with carers irrespective of their level of functional dependency. Unmet needs for weekly services, for people that require home support services, are estimated at 38, 33, 55 and 47 min for personal care, cleaning, social support, and gardening and home maintenance, respectively. The survey also found that most carers and people living with PD agreed that current levels of different types of home care support including nursing were either adequate or insufficient; some carers preferred more services even if the people living with PD were satisfied and some people living with PD wanted more services even if their carers reported needing no extra help. Respite was used by 29 % of people living with PD with carers with two thirds wanting more opportunities for respite. Of the 71 % of people living with PD with carers who had not used respite, less than half stated that they would like to use respite. The 2007 survey was followed by interviews with a sample of survey respondents at different stages of their disorder. In the interviews, most of the people living with Parkinson’s disease commented that continuing to remain at home depended on the rate of degeneration of their disorder as well as the ability of their carers to continue to care. Most of these people and their careers were living day-to-day with a hope that enough support would be made available if and when they need it. As vocal Baby Boomers age, policymakers would do well to acknowledge the diversity of care needs for people with Parkinson’s disease and address the quantum and type of support to meet these needs

    Vietnam military service history and prostate cancer

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    BACKGROUND: Three decades after US and Australian forces withdrew from Vietnam, there has been much public interest in the health consequences of service in Vietnam. One controversial question is whether the risk of prostate cancer amongst Vietnam veterans is increased. This paper examines relationships between military history, family history and risk of prostate cancer in a population-based case control study. METHODS: Cases were selected from the Cancer Registry of Western Australia as incident cases of histologically-confirmed prostate cancer, and controls were age-matched and selected from the Western Australian electoral roll. Study participants were asked to report any military service history and details about that service. RESULTS: Between January 2001 and September 2002, 606 cases and 471 controls aged between 40–75 years were recruited. An increased prostate cancer risk was observed in men reporting they were deployed in Vietnam although this was not statistically significant (OR = 2.12; 95% CI 0.88–5.06). An increased risk was also observed in men reporting prostate cancer in fathers (OR = 1.90; 95% CI 1.20–3.00) or brothers (OR = 2.05; 95% CI 1.20–3.50) diagnosed with prostate cancer. CONCLUSION: These findings support a positive association between prostate cancer and military service history in the Vietnam war and a first degree relative family history of prostate cancer

    Uncertainty quantification for kinetic models in socio-economic and life sciences

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    Kinetic equations play a major rule in modeling large systems of interacting particles. Recently the legacy of classical kinetic theory found novel applications in socio-economic and life sciences, where processes characterized by large groups of agents exhibit spontaneous emergence of social structures. Well-known examples are the formation of clusters in opinion dynamics, the appearance of inequalities in wealth distributions, flocking and milling behaviors in swarming models, synchronization phenomena in biological systems and lane formation in pedestrian traffic. The construction of kinetic models describing the above processes, however, has to face the difficulty of the lack of fundamental principles since physical forces are replaced by empirical social forces. These empirical forces are typically constructed with the aim to reproduce qualitatively the observed system behaviors, like the emergence of social structures, and are at best known in terms of statistical information of the modeling parameters. For this reason the presence of random inputs characterizing the parameters uncertainty should be considered as an essential feature in the modeling process. In this survey we introduce several examples of such kinetic models, that are mathematically described by nonlinear Vlasov and Fokker--Planck equations, and present different numerical approaches for uncertainty quantification which preserve the main features of the kinetic solution.Comment: To appear in "Uncertainty Quantification for Hyperbolic and Kinetic Equations

    Risk factors for breast cancer in young women by oestrogen receptor and progesterone receptor status

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    We used data from 765 cases and 564 controls in the population-based Australian Breast Cancer Family Study to investigate whether, in women under the age of 40, the profile of risk factors differed between breast cancer subtypes defined by joint oestrogen and progesterone receptor status. As hypothesised, no significant differences were found

    Factors influencing preoperative stress response in coronary artery bypass graft patients

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    BACKGROUND: In many studies investigating measures to attenuate the hemodynamic and humoral stress response during induction of anaesthesia, primary attention was paid to the period of endotracheal intubation since it has been shown that even short-lasting sympathetic cardiovascular stimulation may have detrimental effects on patients with coronary artery disease. The aim of this analysis was, however, to identify the influencing factors on high catecholamine levels before induction of anaesthesia. METHODS: Various potential risk factors that could impact the humoral stress response before induction of anaesthesia were recorded in 84 males undergoing coronary aortic bypass surgery, and were entered into a stepwise linear regression analysis. The plasma level of norepinephrine measured immediately after radial artery canulation was chosen as a surrogate marker for the humoral stress response, and it was used as the dependent variable in the regression model. Accordingly, the mean arterial blood pressure, heart rate and the calculated pressure-rate product were taken as parameters of the hemodynamic situation. RESULTS: Stepwise regression analysis revealed that the oral administration of low-dose clonidine (mean dose 1.75 μg·kg(-1)) on the morning of surgery was the only significant predictor (p = 0.004) of the high variation in preoperative norepinephrine plasma levels. This intervention decreased norepinephrine levels by more than 40% compared to no clonidine administration, from 1.26 to 0.75 nmol·l(-1). There was no evidence for dose-responsiveness of clonidine. All other potential predictors were removed from the model as insignificant (p > 0.05). The use of beta-blocker, ace-inhibitors, ejection fraction, and body mass index were significant determinants for the hemodynamic situation (heart rate, mean arterial pressure, pressure rate product) of the patient during the pre-induction period. CONCLUSION: The oral administration of clonidine is the only significant predictor for the observed variation of norepinephrine levels during the preoperative period. Lack of significant dose responsiveness suggests that even a low dose of the drug can attenuate the preoperative stress response and thus is recommended in cardiovascular high risk patients

    Informed consent for MRI and fMRI research: Analysis of a sample of Canadian consent documents

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    <p>Abstract</p> <p>Background</p> <p>Research ethics and the measures deployed to ensure ethical oversight of research (e.g., informed consent forms, ethics review) are vested with extremely important ethical and practical goals. Accordingly, these measures need to function effectively in real-world research and to follow high level standards.</p> <p>Methods</p> <p>We examined approved consent forms for Magnetic Resonance Imaging (MRI) and functional Magnetic Resonance Imaging (fMRI) studies approved by Canadian research ethics boards (REBs).</p> <p>Results</p> <p>We found evidence of variability in consent forms in matters of physical and psychological risk reporting. Approaches used to tackle the emerging issue of incidental findings exposed extensive variability between and within research sites.</p> <p>Conclusion</p> <p>The causes of variability in approved consent forms and studies need to be better understood. However, mounting evidence of administrative and practical hurdles within current ethics governance systems combined with potential sub-optimal provision of information to and protection of research subjects support other calls for more scrutiny of research ethics practices and applicable revisions.</p
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