1,549 research outputs found

    Brain penetrant LRRK2 inhibitor

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    This is the author accepted manuscript. The final version is available from ACS via the DOI in this record. Activating mutations in leucine-rich repeat kinase 2 (LRRK2) are present in a subset of Parkinson's disease (PD) patients and may represent an attractive therapeutic target. Here, we report that a 2-anilino-4-methylamino-5- chloropyrimidine, HG-10-102-01 (4), is a potent and selective inhibitor of wild-type LRRK2 and the G2019S mutant. Compound 4 substantially inhibits Ser910 and Ser935 phosphorylation of both wild-type LRRK2 and G2019S mutant at a concentration of 0.1-0.3 μM in cells and is the first compound reported to be capable of inhibiting Ser910 and Ser935 phosphorylation in mouse brain following intraperitoneal delivery of doses as low as 50 mg/kg. © 2012 American Chemical Society.NIHMedical Research CouncilMichael J Fox foundation for Parkinson’s disease researchPharmaceutical companies supporting the DSTT (AstraZeneca, Boehringer-Ingelheim, GlaxoSmithKline, Merck KgaA and Pfizer

    Mathematical and computational models for bone tissue engineering in bioreactor systems

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    Research into cellular engineered bone grafts offers a promising solution to problems associated with the currently used auto- and allografts. Bioreactor systems can facilitate the development of functional cellular bone grafts by augmenting mass transport through media convection and shear flow-induced mechanical stimulation. Developing successful and reproducible protocols for growing bone tissue in vitro is dependent on tuning the bioreactor operating conditions to the specific cell type and graft design. This process, largely reliant on a trial-and-error approach, is challenging, time-consuming and expensive. Modelling can streamline the process by providing further insight into the effect of the bioreactor environment on the cell culture, and by identifying a beneficial range of operational settings to stimulate tissue production. Models can explore the impact of changing flow speeds, scaffold properties, and nutrient and growth factor concentrations. Aiming to act as an introductory reference for bone tissue engineers looking to direct their experimental work, this article presents a comprehensive framework of mathematical models on various aspects of bioreactor bone cultures and overviews modelling case studies from literature

    PO-145 ERK5 pathway inhibitors inhibit the maintenance of chronic myeloid leukaemia stem cells

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    Introduction Chronic myeloid leukaemia (CML) is a hematopoietic stem cell (HSC)-driven neoplasia characterised by the expression of the constitutively active tyrosine kinase BCR/ABL. CML therapy based on tyrosine kinase inhibitors (TKi) is highly effective in inducing remission but not in targeting leukaemia stem cells (LSC), which sustain the minimal residual disease and are responsible for CML relapse following discontinuation of treatment. Our aim was to address the effects of the inhibition of the ERK5 pathway on the maintenance of CML LSC. Material and methods KCL22 and K562 CML cell lines, patient-derived CML cells or CD34 +peripheral blood cells from healthy donors (informed consent) were incubated in normoxic or hypoxic (0.1% O 2 ) primary cultures (LC1) in the presence or the absence of drugs. At the end of incubation (day 7), cells were analysed on a flow cytometer to determine the expression of stem cell markers or transferred to drug-free normoxic secondary cultures (LC2) to measure LC2 repopulation as a read-out of progenitor/stem cell potential (CRA assay). In the serial Colony Formation Ability (CFA) assay colonies were scored on day 7 of each passage (III passages). In the Long-Term Culture-Initiating Cells (LTC-IC) assay the number of colonies was scored after 14 days. Compounds: XMD8-92 (ERK5 inhibitor) and BIX02189 (MEK5 inhibitor); imatinib and dasatinib (BCR/ABL inhibitors). Results and discussions In CML patient-derived cells and cell lines, we found that the MEK5/ERK5 pathway is active and necessary for optimal proliferation in low oxygen, a condition typical of normal hematopoietic and leukemic stem cell niches. Treatment of primary CML cells with XMD8-92 or BIX02189, but not with TKi, strikingly reduced Culture Repopulation Ability (CRA), serial Colony Formation Ability and Long-Term Culture-Initiating Cells (LTC-IC). Importantly, inhibition of MEK5/ERK5 was effective on CML cells regardless of the presence or absence of imatinib (IM), and did not reduce CRA or LTC-IC of normal CD34 +cells. Interestingly, in hypoxia, combined treatment XMD8-92/IM decreased the expression of genes relevant for stem cell maintenance such as c-MYC, SOX2 and NANOG and the expression of CD26, a CML LSC marker. Conclusion We propose ERK5 pathway inhibitors as a novel therapeutic approach to prevent CML relapse and, in combination with TKi, enhance induction of remission

    The utility of the Historical Clinical Risk -20 Scale as a predictor of outcomes in decisions to transfer patients from high to lower levels of security-A UK perspective

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    <p>Abstract</p> <p>Background</p> <p>Structured Professional Judgment (SPJ) approaches to violence risk assessment are increasingly being adopted into clinical practice in international forensic settings. The aim of this study was to examine the predictive validity of the Historical Clinical Risk -20 (HCR-20) violence risk assessment scale for outcome following transfers from high to medium security in a United Kingdom setting.</p> <p>Methods</p> <p>The sample was predominately male and mentally ill and the majority of cases were detained under the criminal section of the Mental Health Act (1986). The HCR-20 was rated based on detailed case file information on 72 cases transferred from high to medium security. Outcomes were examined, independent of risk score, and cases were classed as "success or failure" based on established criteria.</p> <p>Results</p> <p>The mean length of follow up was 6 years. The total HCR-20 score was a robust predictor of failure at lower levels of security and return to high security. The Clinical and Risk management items contributed most to predictive accuracy.</p> <p>Conclusions</p> <p>Although the HCR-20 was designed as a violence risk prediction tool our findings suggest it has potential utility in decisions to transfer patients from high to lower levels of security.</p

    Development of quality indicators for monitoring outcomes of frail elderly hospitalised in acute care health settings: Study Protocol

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    Background: Frail older people admitted to acute care hospitals are at risk of a range of adverse outcomes, including geriatric syndromes, although targeted care strategies can improve health outcomes for these patients. It is therefore important to assess inter-hospital variation in performance in order to plan and resource improvement programs. Clinical quality outcome indicators provide a mechanism for identifying variation in performance over time and between hospitals, however to date there has been no routine use of such indicators in acute care settings. A barrier to using quality indicators is lack of access to routinely collected clinical data. The interRAI Acute Care (AC) assessment system supports comprehensive geriatric assessment of older people within routine daily practice in hospital and includes process and outcome data pertaining to geriatric syndromes. This paper reports the study protocol for the development of aged care quality indicators for acute care hospitals. Methods/Design. The study will be conducted in three phases:. 1. Development of a preliminary inclusive set of quality indicators set based on a literature review and expert panel consultation,. 2. A prospective field study including recruitment of 480 patients aged 70 years or older across 9 Australian hospitals. Each patient will be assessed on admission and discharge using the interRAI AC, and will undergo daily monitoring to observe outcomes. Medical records will be independently audited, and. 3. Analysis and compilation of a definitive quality indicator set, including two anonymous voting rounds for quality indicator inclusion by the expert panel. Discussion. The approach to quality indicators proposed in this protocol has four distinct advantages over previous efforts: the quality indicators focus on outcomes; they can be collected as part of a routinely applied clinical information and decision support system; the clinical data will be robust and will contribute to better understanding variations in hospital care of older patients; The quality indicators will have international relevance as they will be built on the interRAI assessment instrument, an internationally recognised clinical system

    Zebrafish: A See-Through Host and a Fluorescent Toolbox to Probe Host–Pathogen Interaction

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    In many ways, the zebrafish represents a hybrid between mouse and invertebrate infection models. Powerful forwardgenetic tools that have made invertebrates justifiably famous are not only relatively accessible in the zebrafish, but have been exploited to yield new insights into human infectious diseases, including leprosy and tuberculosis [1]. Transgenic technologies have enabled detailed, non-invasive in vivo visualization of macrophages and neutrophils in pitched battle with bacteria and fungi [2,3]. Reverse genetics with morpholinos, vivo-morpholinos, and zinc-finger nucleases (but unfortunately not homologous recombination, which for the moment remains out of reach in this organism) enable examination of the roles of specific genes during infection. Flexible genetic systems such as Gal4-UAS and Cre-Lox permit tissue-specific transformation and ablation ([3]; Figure 1)

    Pregnancy Incidence and Correlates during the HVTN 503 Phambili HIV Vaccine Trial Conducted among South African Women

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    HIV prevention trials are increasingly being conducted in sub-Saharan Africa. Women at risk for HIV are also at risk of pregnancy. To maximize safety, women agree to avoid pregnancy during trials, yet pregnancies occur. Using data from the HVTN 503/"Phambili" vaccine trial, we report pregnancy incidence during and after the vaccination period and identify factors, measured at screening, associated with incident pregnancy.To enrol in the trial, women agreed and were supported to avoid pregnancy until 1 month after their third and final vaccination ("vaccination period"), corresponding to the first 7 months of follow-up. Unsterilized women, pooled across study arms, were analyzed. Poisson regression compared pregnancy rates during and after the vaccination period. Cox proportional hazards regression identified associations with first pregnancy.Among 352 women (median age 23 yrs; median follow-up 1.5 yrs), pregnancy incidence was 9.6/100 women-years overall and 6.8/100 w-yrs and 11.3/100 w-yrs during and after the vaccination period, respectively [Rate Ratio = 0.60 (0.32-1.14), p = 0.10]. In multivariable analysis, pregnancy was reduced among women who: enrolled at sites providing contraception on-site [HR = 0.43, 95% CI (0.22-0.86)]; entered the trial as injectable contraceptive users [HR = 0.37 (0.21-0.67)] or as consistent condom users (trend) [HR = 0.54 (0.28-1.04)]. Compared with women with a single partner of HIV-unknown status, pregnancy rates were increased among women with: a single partner whose status was HIV-negative [HR = 2.34(1.16-4.73)] and; 2 partners both of HIV-unknown status [HR = 4.42(1.59-12.29)]. Women with 2 more of these risk factors: marijuana use, heavy drinking, or use of either during sex, had increased pregnancy incidence [HR = 2.66 (1.24-5.72)].It is possible to screen South African women for pregnancy risk at trial entry. Providing injectable contraception for free on-site and supporting consistent condom use may reduce incident pregnancy. Screening should determine the substance use, partnering, and HIV status of both members of the couple for both pregnancy and HIV prevention.SA National Health Research Database DOH-27-0207-1539; Clinicaltrials.gov NCT00413725
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