248 research outputs found

    Detection of early osteogenic commitment in primary cells using Raman spectroscopy

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    Major challenges in the development of novel implant surfaces for artificial joints include osteoblast heterogeneity and the lack of a simple and sensitive in vitro assay to measure early osteogenic responses. Raman spectroscopy is a label-free, non-invasive and non-destructive vibrational fingerprinting optical technique that is increasingly being applied to detect biochemical changes in cells. In this study Raman spectroscopy has been used to obtain bone cell-specific spectral signatures and to identify any changes therein during osteoblast commitment and differentiation of primary cells in culture. Murine calvarial osteoblasts (COBs) were extracted and cultured and studied by Raman spectroscopy over a 14 day culture period. Distinct osteogenic Raman spectra were identified after 3 days of culture with strong bands detected for mineral: phosphate ν3 (1030 cm−1) and B-type carbonate (1072 cm−1), DNA (782 cm−1) and collagen matrix (CH2 deformation at 1450 cm−1) and weaker phosphate bands (948 and 970 cm−1). Early changes were detected by Raman spectroscopy compared to a standard enzymatic alkaline phosphatase (ALP) assay and gene expression analyses over this period. Proliferation of COBs was confirmed by fluorescence intensity measurements using the Picogreen dsDNA reagent. Changes in ALP levels were evident only after 14 days of culture and mRNA expression levels for ALP, Col1a1 and Sclerostin remained constant during the culture period. Sirius red staining for collagen deposition also revealed little change until day 14. In contrast Raman spectroscopy revealed the presence of amorphous calcium phosphate (945–952 cm−1) and carbonated apatite (957–962 cm−1) after only 3 days in culture and octacalcium phosphate (970 cm−1) considered a transient mineral phase, was detected after 5 days of COBs culture. PCA analysis confirmed clear separation between time-points. This study highlights the potential of Raman spectroscopy to be utilised for the early and specific detection of proliferation and differentiation changes in primary cultures of bone cells

    Local origins impart conserved bone type-related differences in human osteoblast behaviour

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    Osteogenic behaviour of osteoblasts from trabecular, cortical and subchondral bone were examined to determine any bone type-selective differences in samples from both osteoarthritic (OA) and osteoporotic (OP) patients. Cell growth, differentiation; alkaline phosphatase (TNAP) mRNA and activity, Runt-related transcription factor-2 (RUNX2), SP7-transcription factor (SP7), bone sialoprotein-II (BSP-II), osteocalcin/bone gamma-carboxyglutamate (BGLAP), osteoprotegerin (OPG, TNFRSF11B), receptor activator of nuclear factor-κβ ligand (RANKL, TNFSF11) mRNA levels and proangiogenic vascular endothelial growth factor-A (VEGF-A) mRNA and protein release were assessed in osteoblasts from paired humeral head samples from age-matched, human OA/OP (n = 5/4) patients. Initial outgrowth and increase in cell number were significantly faster (p < 0.01) in subchondral and cortical than trabecular osteoblasts, in OA and OP, and this bone type-related differences were conserved despite consistently faster growth in OA. RUNX2/SP7 levels and TNAP mRNA and protein activity were, however, greater in trabecular than subchondral and cortical osteoblasts in OA and OP. BSP-II levels were significantly greater in trabecular and lowest in cortical osteoblasts in both OA and OP. In contrast, BGLAP levels showed divergent bone type-selective behaviour; highest in osteoblasts from subchondral origins in OA and trabecular origins in OP. We found virtually identical bone type-related differences, however, in TNFRSF11B:TNFSF11 in OA and OP, consistent with greater potential for paracrine effects on osteoclasts in trabecular osteoblasts. Subchondral osteoblasts (OA) exhibited highest VEGF-A mRNA levels and release. Our data indicate that human osteoblasts in trabecular, subchondral and cortical bone have inherent, programmed diversity, with specific bone type-related differences in growth, differentiation and pro-angiogenic potential in vitro

    Utilizing the Innovative Leadership Behavior Inventory and Relationship Marketing as Critical Elements for Teaching/Learning Entrepreneurial Leadership (EL)

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    The focus of this paper will be on utilizing the five-factor Leader Behavior Inventory (LBI) as the structure, and various teaching or learning pedagogy and related processes and relationships as the intervening variables in order to help entrepreneurs assess then enhance their potential leadership behavior. In turn, this should foster the decision process necessary to accomplish enterprise building or organizational development thus enhancing the cycle time for critical change. Should the LBI and associated assessment tools and processes indicate such, the best practice strategies may involve bringing in professional management, slowing the growth of the enterprise to allow for leadership development, or an appropriate exit strategy

    Lucro líquido do franqueado: um sinal para a escolha de franquia em época de crise

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    Este artículo aborda desde la perspectiva de la Teoría de Señales la elección de una franquicia por un potencial franquiciado que elige este canal de distribución por primera vez. El objetivo es analizar la relación entre algunas señales enviadas por el franquiciador y la elección de una franquicia por el potencial franquiciado. Concluimos que los efectos de las variables macroeconómicas de España en el periodo 2006-2013 influyeron en los ingresos netos de los franquiciados para que se convirtiera en una señal empleada por éstos a la hora de elegir la franquicia donde abrir un establecimiento.This paper adopts the perspective of Theory of Signals to discuss how someone starting a business as a franchisee for the first time can choose a suitable franchise brand. The aim was to analyze the relationship between certain signals sent by the franchisor and the choice of a franchise brand by the prospective franchisee. Using panel data, we found that the effects of macroeconomic variables in Spain for the 2006-2013 crisis period influenced franchisees' net income, which thus became a relevant signal in their process of choosing a franchise brand to start a business.Sob a perspectiva da Teoria de Sinais, este artigo aborda a seleção de uma franquia por um franqueado que elege esse potencial canal de distribuição pela primeira vez. O objetivo é analisar a relação entre alguns sinais enviados pelo franqueador e a escolha de uma franquia pelo potencial franqueado. Usando a metodologia de dados em painel, os resultados obtidos nos permitiram concluir que os efeitos das variáveis macroeconômicas da Espanha no período de crise econômica (2006-2013) influenciaram as receitas líquidas dos franqueados, tornando-se um sinal para eles elegerem onde abrir um estabelecimento franqueado

    TEM analysis of apatite surface layers observed on zinc based glass polyalkenoate cements

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    peer-reviewedGlass polyalkenoate cements (GPCs) are acid base cements formed by the reaction of an aqueous solution of polyalkenoic acid, usually polyacrylic acid (PAA) with an acid degradable aluminosilicate glass. The result of the reaction is cement consisting of reacted and unreacted glass particles embedded in a polysalt matrix. In addition to these conventional GPCs, aluminium free glass polyalkenoate cements based on zinc silicate glasses (Zn-GPCs) exhibit significant potential as bone cements for several reasons. Primarily, they are formulated without the inclusion of aluminium (Al) [1] in the glass phase and thus eliminate clinical complications arising from the release of the Al3+ ion from the cement in vivo. Such complications have, in the past, included aluminium induced encephalopathy [2-5] and defective mineralisation of cancellous bone [6]. Secondly, Zn-GPCs set without a significant evolution of heat, when compared with commercial bone cements such as Spineplex ® (Stryker, Limerick, Ireland). Finally, these materials can be tailored to release clinically beneficial ions into surrounding tissues [7]. In addition to Zn, these cements have been synthesized to contain strontium (Sr) [8, 9]. Both Sr and Zn inhibit osteoclastic turnover and promote osteoblastic turnover, resulting in increased bone strength and decreased fracture risk [10-14].Acceptedpeer-reviewe

    Does publication bias inflate the apparent efficacy of psychological treatment for major depressive disorder? A systematic review and meta-analysis of US national institutes of health-funded trials

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    Background The efficacy of antidepressant medication has been shown empirically to be overestimated due to publication bias, but this has only been inferred statistically with regard to psychological treatment for depression. We assessed directly the extent of study publication bias in trials examining the efficacy of psychological treatment for depression. Methods and Findings We identified US National Institutes of Health grants awarded to fund randomized clinical trials comparing psychological treatment to control conditions or other treatments in patients diagnosed with major depressive disorder for the period 1972–2008, and we determined whether those grants led to publications. For studies that were not published, data were requested from investigators and included in the meta-analyses. Thirteen (23.6%) of the 55 funded grants that began trials did not result in publications, and two others never started. Among comparisons to control conditions, adding unpublished studies (Hedges’ g = 0.20; CI95% -0.11~0.51; k = 6) to published studies (g = 0.52; 0.37~0.68; k = 20) reduced the psychotherapy effect size point estimate (g = 0.39; 0.08~0.70) by 25%. Moreover, these findings may overestimate the "true" effect of psychological treatment for depression as outcome reporting bias could not be examined quantitatively. Conclusion The efficacy of psychological interventions for depression has been overestimated in the published literature, just as it has been for pharmacotherapy. Both are efficacious but not to the extent that the published literature would suggest. Funding agencies and journals should archive both original protocols and raw data from treatment trials to allow the detection and correction of outcome reporting bias. Clinicians, guidelines developers, and decision makers should be aware that the published literature overestimates the effects of the predominant treatments for depression

    Social interaction patterns, therapist responsiveness, and outcome in treatments for borderline personality disorder.

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    Inflexible social interaction patterns are defining features of borderline personality disorder (BPD). Specific beliefs about the self and others may be activated across interaction situations, often leading to instable relationships. It may be pivotal to address these difficulties in early treatment phases, through appropriate therapist responsiveness, which means an adaptation of therapist's activity to their client's behaviours using emerging information in the process (Stiles, 2009, Clinical Psychology: Science and Practice, 16, 86). In this process-outcome study, responsiveness is operationalized by the motive-oriented therapeutic relationship (Caspar, 2007, Handbook of psychotherapeutic case formulations, 2nd ed., 251-289, Guilford), based on the Plan analysis case formulation. The present study assesses the interplay between social interaction problems and therapist responsiveness, explaining symptoms at discharge and the therapeutic alliance. In total, N = 50 clients with BPD entered the study, and standard and responsive treatments were compared. Social interaction patterns were assessed by the newly developed Borderline Interaction Patterns Scale (BIPS), applied to recorded material of three sessions per therapy. Outcome was measured by general symptoms (OQ-45), borderline symptoms (BSL-23), interpersonal problems (IIP), and the therapeutic alliance (WAI). Results suggest that in standard treatment, social interaction patterns are neither related to outcome nor the therapeutic alliance. In responsive treatment, more activation of social interaction patterns predicted better outcome on IIP and lower therapist ratings of the alliance. The conclusions seem promising for specific effectiveness of responsive treatments in particular in the interpersonal problem area of BPD. Identifying social interaction patterns early in treatment may be a crucial pathway to change for BPD. Responsive therapy activating social interaction patterns may be crucial for better outcome. Future research should focus on mechanisms of change in early treatment phases for BPD. New scale for assessing social interaction patterns specific to borderline personality disorder

    Outcome of crisis intervention for borderline personality disorder and post traumatic stress disorder: a model for modification of the mechanism of disorder in complex post traumatic syndromes

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    <p>Abstract</p> <p>Background</p> <p>This study investigates the outcome of crisis intervention for chronic post traumatic disorders with a model based on the theory that such crises manifest trauma in the present. The sufferer's behavior is in response to the current perception of dependency and entrapment in a mistrusted relationship. The mechanism of disorder is the sufferer's activity, which aims to either prove or disprove the perception of entrapment, but, instead, elicits more semblances of it in a circular manner. Patients have reasons to keep such activity private from therapy and are barely aware of it as the source of their symptoms.</p> <p>Methods</p> <p>The hypothesis is that the experimental intervention will reduce symptoms broadly within 8 to 24 h from initiation of treatment, compared to treatment as usual. The experimental intervention sidesteps other symptoms to engage patients in testing the trustworthiness of the troubled relationship with closure, thus ending the circularity of their own ways. The study compares 32 experimental subjects with 26 controls at similar crisis stabilization units.</p> <p>Results</p> <p>The results of the Brief Psychiatric Rating Scale (BPRS) supported the hypothesis (both in total score and for four of five subscales), as did results with Client Observation, a pilot instrument designed specifically for the circular behavior targeted by the experimental intervention. Results were mostly non-significant from two instruments of patient self-observation, which provided retrospective pretreatment scores.</p> <p>Conclusions</p> <p>The discussion envisions further steps to ascertain that this broad reduction of symptoms ensues from the singular correction that distinguishes the experimental intervention.</p> <p>Trial registration</p> <p>Protocol Registration System NCT00269139. The PRS URL is <url>https://register.clinicaltrials.gov</url></p
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