634 research outputs found

    Coordination-driven magnetic-to-nonmagnetic transition in manganese doped silicon clusters

    Full text link
    The interaction of a single manganese impurity with silicon is analyzed in a combined experimental and theoretical study of the electronic, magnetic, and structural properties of manganese-doped silicon clusters. The structural transition from exohedral to endohedral doping coincides with a quenching of high-spin states. For all geometric structures investigated, we find a similar dependence of the magnetic moment on the manganese coordination number and nearest neighbor distance. This observation can be generalized to manganese point defects in bulk silicon, whose magnetic moments fall within the observed magnetic-to-nonmagnetic transition, and which therefore react very sensitively to changes in the local geometry. The results indicate that high spin states in manganese-doped silicon could be stabilized by an appropriate lattice expansion

    PIB is a non-specific imaging marker of amyloid-beta (Aβ) peptide-related cerebral amyloidosis

    Get PDF
    The in vivo imaging probe [11C]-PIB (Pittsburgh Compound B, N-methyl[11C]2-(4′-methylaminophenyl-6-hydroxybenzathiazole) is under evaluation as a key imaging tool in Alzheimer's disease (AD) and to date has been assumed to bind with high affinity and specificity to the amyloid structures associated with classical plaques (CPs), one of the pathological hallmarks of the disease. However, no studies have systematically investigated PIB binding to human neuropathological brain specimens at the tracer concentrations achieved during in vivo imaging scans. Using a combination of autoradiography and histochemical techniques, we demonstrate that PIB, in addition to binding CPs clearly delineates diffuse plaques and cerebrovascular amyloid angiopathy (CAA). The interaction of PIB with CAA was not fully displaceable and this may be linked to the apolipoprotein E-ε4 allele. PIB was also found to label neurofibrillary tangles, although the overall intensity of this binding was markedly lower than that associated with the amyloid-beta (Aβ) pathology. The data provide a molecular explanation for PIB's limited specificity in diagnosing and monitoring disease progression in AD and instead indicate that the ligand is primarily a non-specific marker of Aβ-peptide related cerebral amyloidosi

    Comparative studies on promotion of health and life style of hospital staff in Sweden and Poland

    Get PDF
    Introduction. Recently, an increase has been observed in the number of patients suffering from diseases which are the consequence of an anti-health life style; therefore it is necessary to undertake proper actions in this area, including those addressed to hospital staff. Objectives. 1) Comparison of self-reported state of health and life style between hospital staff in Sweden and Poland, and the motivation of these employees to change the to-date life style for one that is more health promoting. 2) Presentation, based on Swedish experiences in the field of health promotion in hospitals, of the possibilities to implement these changes in Polish conditions. Material and method. The study covered the staff from the following hospitals: 1) hospitals in Ostergotland County, Sweden, and 2) the Ludwik Perzyna Regional Polyclinical Hospital in Kalisz, Poland. The studies were conducted in parallel in Sweden and in Poland during the fourth quarter 2010. The research instrument was a questionnaire form. Results. The following measures should be undertaken by the staff of Polish hospitals: an increase in the consumption of fruit and vegetables, physical activity, organization of workshops aimed at the shaping of skills of coping with stress and relieving stress, assistance in reducing body weight and increasing physical activity. Obligatory breaks at work should be introduced for the consumption of meals and intake of beverages, including water, promotion of fluid replacement would reduce fatigue. An obligatory lunchtime would allow each employee to consume a decent meal, and consequently have respite away from one's own work activities. In order to have a well-functioning staff an employer should, in his/her own interest, decrease potential sick absenteeism, provide incentives for motor activity, e.g. by the organization of groups, reduction of weekly working time on behalf of documented physical activity, or financial support for the purchase of tickets for various forms of physical exercises. Promotion of collective exercise, e.g. common nordic walking for 30 min. during lunch, competition in the largest number of steps made. Promotion of healthy nutrition by the preparation of recipes for meals, several exemplary healthy meals in the form of a healthy alternative breakfast. During this event, a basket of fruit is provided, instead of cakes and sweets. Conclusions. 1) The life style of the staff of health care facilities is more health promoting in Sweden than in Poland. 2) It is possible to change the life style of employees of health care facilities into one that is more health promoting. Changes in this area have been made in Sweden with a great success; therefore, it is worthwhile implementing in Poland these Swedish experiences which may function also in Polish conditions. 3) The foundations of health promotion in enterprises have been known for a long time; however, considering the fact that the comparative studies show that these foundations are more advanced in Sweden, it is necessary that Polish employers devote more attention to this problem, and become interested in Swedish experiences in this area

    De-implementation of low value castration for men with prostate cancer: protocol for a theory-based, mixed methods approach to minimizing low value androgen deprivation therapy (DeADT)

    Full text link
    Abstract Background Men with prostate cancer are often castrated with long-acting injectable drugs termed androgen deprivation therapy (ADT). Although many benefit, ADT is also used in patients with little or nothing to gain. The best ways to stop this practice are unknown, and range from blunt pharmacy restrictions to informed decision-making. This study will refine and pilot two different de-implementation strategies for reducing ADT use among those unlikely to benefit in preparation for a comparative effectiveness trial. Methods/design This innovative mixed methods research program has three aims. Aim 1: To assess preferences and barriers for de-implementation of chemical castration in prostate cancer. Guided by the theoretical domains framework (TDF), urologists and patients from facilities with the highest and lowest castration rates across the VA will be interviewed to identify key preferences and de-implementation barriers for reducing castration as prostate cancer treatment. This qualitative work will inform Aim 2 while gathering rich information for two proposed pilot intervention strategies. Aim 2: To use a discrete choice experiment (DCE), a novel barrier prioritization approach, for de-implementation strategy tailoring. The investigators will conduct national surveys of urologists to prioritize key barriers identified in Aim 1 for stopping incident castration as localized prostate cancer treatment using a DCE experiment design. These quantitative results will identify the most important barriers to be addressed through tailoring of two pilot de-implementation strategies in preparation for Aim 3 piloting. Aim 3: To pilot two tailored de-implementation strategies to reduce castration as localized prostate cancer treatment. Building on findings from Aims 1 and 2, two de-implementation strategies will be piloted. One strategy will focus on formulary restriction at the organizational level and the other on physician/patient informed decision-making at different facilities. Outcomes will include acceptability, feasibility, and scalability in preparation for an effectiveness trial comparing these two widely varying de-implementation strategies. Discussion Our innovative approach to de-implementation strategy development is directly aligned with state-of-the-art complex implementation intervention development and implementation science. This work will broadly advance de-implementation science for low value cancer care, and foster participation in our de-implementation evaluation trial by addressing barriers, facilitators, and concerns through pilot tailoring. Trial registration ClinicalTrials.gov Identifier: NCT03579680 , First Posted July 6, 2018.https://deepblue.lib.umich.edu/bitstream/2027.42/146541/1/13012_2018_Article_833.pd

    The implications of baseline bone‐health assessment at initiation of androgen‐deprivation therapy for prostate cancer

    Full text link
    Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/142891/1/bju14075.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/142891/2/bju14075_am.pd

    Genotype-Phenotype correlations in multiple sclerosis: HLA genes influence disease severity inferred by 1HMR spectroscopy and MRI measures

    Get PDF
    Genetic susceptibility to multiple sclerosis (MS) is associated with the human leukocyte antigen (HLA) DRB1*1501 allele. Here we show a clear association between DRB1*1501 carrier status and four domains of disease severity in an investigation of genotype-phenotype associations in 505 robust, clinically well characterized MS patients evaluated cross-sectionally: (i) a reduction in the N-acetyl-aspartate (NAA) concentration within normal appearing white matter (NAWM) via 1HMR spectroscopy (P = 0.025), (ii) an increase in the volume of white matter (WM) lesions utilizing conventional anatomical MRI techniques (1,127 mm3; P = 0.031), (iii) a reduction in normalized brain parenchymal volume (nBPV) (P = 0.023), and (iv) impairments in cognitive function as measured by the Paced Auditory Serial Addition Test (PASAT-3) performance (Mean Z Score: DRB1*1501+: 0.110 versus DRB1*1501-: 0.048; P = 0.004). In addition, DRB1*1501+ patients had significantly more women (74% versus 63%; P = 0.009) and a younger mean age at disease onset (32.4 years versus 34.3 years; P = 0.025). Our findings suggest that DRB1*1501 increases disease severity in MS by facilitating the development of more T2-foci, thereby increasing the potential for irreversible axonal compromise and subsequent neuronal degeneration, as suggested by the reduction of NAA concentrations in NAWM, ultimately leading to a decline in brain volume. These structural aberrations may explain the significant differences in cognitive performance observed between DRB1*1501 groups. The overall goal of a deep phenotypic approach to MS is to develop an array of meaningful biomarkers to monitor the course of the disease, predict future disease behaviour, determine when treatment is necessary, and perhaps to more effectively recommend an available therapeutic interventio

    PEG Minocycline-Liposomes Ameliorate CNS Autoimmune Disease

    Get PDF
    Minocycline is an oral tetracycline derivative with good bioavailability in the central nervous system (CNS). Minocycline, a potent inhibitor of matrix metalloproteinase (MMP)-9, attenuates disease activity in experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis (MS). Potential adverse effects associated with long-term daily minocycline therapy in human patients are concerning. Here, we investigated whether less frequent treatment with long-circulating polyethylene glycol (PEG) minocycline liposomes are effective in treating EAE.Performing in vitro time kinetic studies of PEG minocycline-liposomes in human peripheral blood mononuclear cells (PBMCs), we determined that PEG minocycline-liposome preparations stabilized with CaCl(2) are effective in diminishing MMP-9 activity. Intravenous injections of PEG minocycline-liposomes every five days were as effective in ameliorating clinical EAE as daily intraperitoneal injections of minocycline. Treatment of animals with PEG minocycline-liposomes significantly reduced the number of CNS-infiltrating leukocytes, and the overall expression of MMP-9 in the CNS. There was also a significant suppression of MMP-9 expression and proteolytic activity in splenocytes of treated animals, but not in CNS-infiltrating leukocytes. Thus, leukocytes gaining access to the brain and spinal cord require the same absolute amount of MMP-9 in all treatment groups, but minocycline decreases the absolute cell number.Our data indicate that less frequent injections of PEG minocycline-liposomes are an effective alternative pharmacotherapy to daily minocycline injections for the treatment of CNS autoimmune diseases. Also, inhibition of MMP-9 remains a promising treatment target in EAE and patients with MS
    corecore