410 research outputs found

    Using Rasch analysis to form plausible health states amenable to valuation: the development of CORE-6D from CORE-OM in order to elicit preferences for common mental health problems

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    Purpose: To describe a new approach for deriving a preference-based index from a condition specific measure that uses Rasch analysis to develop health states. Methods: CORE-OM is a 34-item instrument monitoring clinical outcomes of people with common mental health problems. CORE-OM is characterised by high correlation across its domains. Rasch analysis was used to reduce the number of items and response levels in order to produce a set of unidimensionally-behaving items, and to generate a credible set of health states corresponding to different levels of symptom severity using the Rasch item threshold map. Results: The proposed methodology resulted in the development of CORE-6D, a 2-dimensional health state description system consisting of a unidimensionally-behaving 5-item emotional component and a physical symptom item. Inspection of the Rasch item threshold map of the emotional component helped identify a set of 11 plausible health states, which, combined with the physical symptom item levels, will be used for the valuation of the instrument, resulting in the development of a preference-based index. Conclusions: This is a useful new approach to develop preference-based measures where the domains of a measure are characterised by high correlation. The CORE-6D preference-based index will enable calculation of Quality Adjusted Life Years in people with common mental health problems

    A Stewardship Cost Perspective on the Governance of Delegation Relationships:The Case of Social Franchising

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    We explore how nonprofits can effectively govern delegation relationships. We extend stewardship theory by conceptualizing stewardship costs—costs in delegation relationships based on stewardship behavior. As stewards are theorized as other-regarding, self-actualizing, and intrinsically motivated, so far, literature almost exclusively points to the positive performance potential of stewardship behavior. Addressing this shortcoming, we develop propositions showing how stewardship selection costs rooted in the psychological characteristics of stewardship behavior and stewardship management costs rooted in situational factors of stewardship behavior occur during relationship formation and maintenance, and how they counteract the potential to increase performance. We identify and systematize opportunity costs of delayed growth, limited growth potential, and lost standardization gains, as well as increased selection and management costs. To demonstrate the theoretical potential and empirical relevance of our framework, we illustrate our arguments by referring to social franchising, a scaling strategy considered relevant for nonprofits as well as social enterprises

    Design and feasibility testing of a novel group intervention for young women who binge drink in groups

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    BackgroundYoung women frequently drink alcohol in groups and binge drinking within these natural drinking groups is common. This study describes the design of a theoretically and empirically based group intervention to reduce binge drinking among young women. It also evaluates their engagement with the intervention and the acceptability of the study methods.MethodsFriendship groups of women aged 18–35 years, who had two or more episodes of binge drinking (>6 UK units on one occasion; 48g of alcohol) in the previous 30 days, were recruited from the community. A face-to-face group intervention, based on the Health Action Process Approach, was delivered over three sessions. Components of the intervention were woven around fun activities, such as making alcohol free cocktails. Women were followed up four months after the intervention was delivered. Results The target of 24 groups (comprising 97 women) was recruited. The common pattern of drinking was infrequent, heavy drinking (mean consumption on the heaviest drinking day was UK 18.1 units). Process evaluation revealed that the intervention was delivered with high fidelity and acceptability of the study methods was high. The women engaged positively with intervention components and made group decisions about cutting down. Twenty two groups set goals to reduce their drinking, and these were translated into action plans. Retention of individuals at follow up was 87%.ConclusionsThis study successfully recruited groups of young women whose patterns of drinking place them at high risk of acute harm. This novel approach to delivering an alcohol intervention has potential to reduce binge drinking among young women. The high levels of engagement with key steps in the behavior change process suggests that the group intervention should be tested in a full randomised controlled trial

    Divergent Serpentoviruses in Free-Ranging Invasive Pythons and Native Colubrids in Southern Florida, United States

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    Burmese python (Python bivittatus) is an invasive snake that has significantly affected ecosystems in southern Florida, United States. Aside from direct predation and competition, invasive species can also introduce nonnative pathogens that can adversely affect native species. The subfamily Serpentovirinae (order Nidovirales) is composed of positive-sense RNA viruses primarily found in reptiles. Some serpentoviruses, such as shingleback nidovirus, are associated with mortalities in wild populations, while others, including ball python nidovirus and green tree python nidovirus can be a major cause of disease and mortality in captive animals. To determine if serpentoviruses were present in invasive Burmese pythons in southern Florida, oral swabs were collected from both free-ranging and long-term captive snakes. Swabs were screened for the presence of serpentovirus by reverse transcription PCR and sequenced. A total serpentovirus prevalence of 27.8% was detected in 318 python samples. Of the initial swabs from 172 free-ranging pythons, 42 (24.4%) were positive for multiple divergent viral sequences comprising four clades across the sampling range. Both sex and snout-vent length were statistically significant factors in virus prevalence, with larger male snakes having the highest prevalence. Sampling location was statistically significant in circulating virus sequence. Mild clinical signs and lesions consistent with serpentovirus infection were observed in a subset of sampled pythons. Testing of native snakes (n = 219, 18 species) in part of the python range found no evidence of python virus spillover; however, five individual native snakes (2.3%) representing three species were PCR positive for unique, divergent serpentoviruses. Calculated pairwise uncorrected distance analysis indicated the newly discovered virus sequences likely represent three novel genera in the subfamily Serpentovirinae. This study is the first to characterize serpentovirus in wild free-ranging pythons or in any free-ranging North America reptile. Though the risk these viruses pose to the invasive and native species is unknown, the potential for spillover to native herpetofauna warrants further investigation

    The Fourth Bioelectronic Medicine Summit "Technology Targeting Molecular Mechanisms": current progress, challenges, and charting the future.

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    There is a broad and growing interest in Bioelectronic Medicine, a dynamic field that continues to generate new approaches in disease treatment. The fourth bioelectronic medicine summit "Technology targeting molecular mechanisms" took place on September 23 and 24, 2020. This virtual meeting was hosted by the Feinstein Institutes for Medical Research, Northwell Health. The summit called international attention to Bioelectronic Medicine as a platform for new developments in science, technology, and healthcare. The meeting was an arena for exchanging new ideas and seeding potential collaborations involving teams in academia and industry. The summit provided a forum for leaders in the field to discuss current progress, challenges, and future developments in Bioelectronic Medicine. The main topics discussed at the summit are outlined here

    Untersuchungen zum Einfluss von thrombozytären Wachstumsfaktoren auf den zellvermittelten Abbau eines nanopartikulären Knochenersatzstoffes auf Hydroxylapatitbasis : eine experimentelle Studie am Miniaturschwein

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    Ziel der vorliegenden tierexperimentellen Studie am Miniaturschwein war es, den Einfluss von plättchenreichem Plasma (PRP) auf den zellvermittelten Abbau eines nanopartikulären Hydroxylapatits (HA) in der Frühphase der Knochendefektheilung zu untersuchen. Hierzu wurden 26 männliche Miniaturschweine der Rasse Mini-Lewe in drei Versuchsgruppen eingeteilt und jeweils ein standardisierter Knochendefekt in der Intercondylarregion des rechten Femurs angelegt. Die Defekte wurden entweder mit dem Knochenersatzstoff (Gruppe I/PRP-,n = 11) oder dem Knochenersatzstoff kombiniert mit PRP (Gruppe II/PRP+, n = 11) befüllt. In einer Kontrollgruppe (n = 4) blieben die Defekte unbefüllt. Während der Implantationsoperation wurden bei sechs Tieren jeweils 250 ml Vollblut entnommen, aus dem anschließend durch fraktionierte Zentrifugation plättchenreiches Plasma gewonnen wurde. Die enthaltenen Thrombozyten wurden durch den Zusatz von Thrombin und Kalziumglukonat zur Degranulation angeregt, wodurch die enthaltenen Wachstumsfaktoren aus den alpha-Granula freigesetzt wurden. Zu diesen Wachstumsfaktoren gehören Platelet Derived Growth Factor AB und BB (PDGF AB, BB), Transforming Growth Factor ß 1 (TGF beta1), Vascular Endothelial Growth Factor (VEGF) und basic Fibroblast Growth Factor (bFGF). Die Konzentration der genannten Wachstumsfaktoren wurde mit Hilfe der ELISA-Technik bestimmt. Sie lagen zwischen Faktor 1,6 für TGF-beta1 und Faktor 24,4 für bFGF. 20 Tage post operationem fand die Explantation der operierten distalen Femura statt. Zur lichtmikroskopischen Untersuchung fanden die Knochen-Implantat-Proben Eingang in unterschiedliche Techniken der Einbettung (Paraffin-, Kunststoffeinbettungen), Präparation (Paraffinschnitte, Kunststoffschnitte und Schliffpräparationen), Färbung (Toluidinblau, Haematoxylin-Eosin, Safranin) und Histochemie (Enzym-, Immunhistochemie). Darüber hinaus wurden transmissionselektronenmikroskopische und computergestützte histomorphometrische Untersuchungen durchgeführt. Wie die Ergebnisse der Licht- und Transmissionselektronenmikroskopie aufgezeigt haben, erfolgt in den mit Knochenersatzmaterial behandelten Versuchsgruppen, unabhängig von der PRP-Applikation, die HA-Degradation hydrolytisch und Makrophagen-vermittelt. Die Makrophagen-Population wird durch Riesenzellen vom Langhans-Typ repräsentiert. Diese polarisierten Polykaryen adhärieren über ihre apikale Membrandomäne an den Implantatoberflächen. Das subplasmalemmale Zytoplasma ist immunhistochemisch durch Vimentin-Kondensationen gekennzeichnet. Nicht-adhärente, frei im Granulationsgewebe lokalisierte Polykaryen zeigen dagegen ein homogenes Vimentin-Verteilungsmuster im Zytoplasma. Der zelluläre Abbau des HA erfolgt mittels Phagozytose, indem die Polykaryen den "Fremdkörper" mit pseudopodienartigen Zytoplasmaausläufern umschließen und in ihr Zytoplasma inkorporieren. Diese Art der Degradation wird durch den post implantationem stattfindenden Zerfall des Knochenersatzmaterials in zahlreiche kleine Partikel unterstützt. Die hieraus resultierende Vergrößerung der Implantatoberfläche bietet einer Vielzahl von Zellen die Möglichkeit zur Haftung. Die festgestellten Expressionsmuster des CD44- Membranglykoproteins verweisen auf dessen funktionelle Rolle im Rahmen der Fusion mononukleärer Makrophagen zu multinukleären Riesenzellen. Die darüber hinaus beobachtete Umverteilung von CD44 von der apikalen zur basalen Membrandomäne bei Implantatassoziierten Polykaryen ist als transientes Geschehen im Zuge der Adhäsion zu interpretieren. Der hohe Aktivitätsstatus der adhärenten Polykaryen ist immunhistochemisch durch eine intensive Kathepsin K-Expression gekennzeichnet. Die vergleichende histomorphometrische Auswertung der mit HA aufgefüllten Defekte dokumentiert eine Verdopplung der Anzahl von Polykaryen in der Gruppe "Knochenersatzstoff mit PRP". Ein auf Basis der Messergebnisse durchgeführter Wilcoxon-Rangsummentest verweist auf den hochsignifikanten Einfluss (p < 0,01) des Faktors PRP auf die Ausdehnung Tartrat-resistenter saurer Phosphatase-positiver Areale in den Präparaten. Diese Effekte können sowohl auf den im PRP angereicherten Wachstumsfaktoren als auch auf dem homologen Charakter der PRP-Zubereitung beruhen. Die beobachteten Polykaryen – sogenannte "Fremdkörperriesenzellen" – sind auch immer Indikatoren einer stattfindenden Entzündungsreaktion. Die histomorphometrisch dargestellte, deutlich verstärkte Fremdkörperreaktion in Gruppe II/PRP+ kann auf die PRP-Applikation zurückgeführt werden. Im weiteren Heilungsverlauf kann dies zu einer Verzögerung der knöchernen Konsolidierung der Defekte führen.Aim of the current experimental study in Minipigs was to examine the effects of homologous platelet-rich plasma (PRP) on the cell-mediated degradation of a nanoparticulate hydroxyapatite (HA) during the early phase of bone defect healing. Twenty-six male "Lewe" minipigs were divided into three groups. Standardized bone defects were created in the intercondylar region of the right femur of each pig and were filled with HA (Group I/PRP-, n = 11) or HA + PRP (Group II/PRP+, n = 11). The defects of the control group (n = 4) were left empty. During the implantation procedure blood was drawn from six minipigs (250 ml each). PRP was isolated from these blood samples after several centrifugation steps. After the addition of thrombin and calcium gluconate growth factors were released from the alpha-granules of the thrombocytes which were enriched within the PRP. Some of these growth factors are Platelet Derived Growth Factor AB and BB (PDGF AB, BB), Transforming Growth Factor ß 1 (TGF beta1), Vascular Endothelial Growth Factor (VEGF) and basic Fibroblast Growth Factor (bFGF). The level of enrichment of these growth factors was controlled by the ELISA technique. Growth factor enrichment within the PRP ranged from 1.6 fold (TGF-beta1) to 24.4 fold (bFGF). After 20 days the treated distal femura were explanted. For light microscopical examination different tissue embedding methods (paraffine, plastic, resin), sectioning techniques (paraffine sections, plastic and resin sections, sawing and grinding sections), staining procedures (toluidine blue, hematoxylin eosin, safranin) and histochemical methods (enzyme- and immunohistochemistry) were performed. Additionally transmission electron microscopy and computer-assisted histomorphometry were used. The results of light microscopy and transmission electron microscopy showed that regardless of the addition of PRP, the HA is degraded by hydrolysis and macrophages. The population of macrophages consists of Langhans-type giant cells. The adhesion of the polarized polykaryons at the surfaces of the implant is mediated by the apical domain of the plasmamembranes. Vimentin condensations of the cytoplasm are attached to the apical plasmalemma. In contrast, non-adherent polykaryons of the granulation tissue reveal a homogeneous Vimentin distribution pattern within their cytoplasma. As shown ultrastructurally, the implant is degraded by means of phagocytosis. The implant particles are encircled by pseudopodia of the polykaryons and become incorporated into the cytoplasma. The degradation process is supported by disintegration of the bone substitute into numerous small particles after implantation. This disintegration causes enlargement of the implant surface and increases the probability of phagocyte adhesion. The pattern of CD44 expression points towards a functional role of the molecule during fusion of mononucleated macrophages into multinucleated giant cells. Implant-associated polykaryons show CD44 immunoreactivity only along the basal domains of the cytomembrane. This pattern can be interpreted as a temporal event during adhesion. Adherent polykaryons are further characterized by strong cathepsin K expression. The histomorphometric examination demonstrates twice as much foreign body giant cells in "Group II/PRP+" as in "Group I/PRP-". Based on these results, a Wilcoxon-signed-rank test was performed and a highly significant effect (p < 0.01) of PRP on the expansion of tartrate resistent acid phophatase (TRAP)-positive areas within bone defects could be demonstrated. This effect could be a result of the substution of PRP or of its homologous character. The polykaryons descibed in this work - so-called Foreign Body Giant Cells - are also indicators of inflammation. The enhanced cellular reaction observed in Group II/PRP+ must be interpreted as a strong foreign body reaction, triggered by the addition of PRP. It cannot be excluded that the strong inflammation reaction will lead to delayed bone formation in the course of healing

    Induction of autophagy is a key component of all-trans-retinoic acid-induced differentiation in leukemia cells and a potential target for pharmacological modulation

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    Acute myeloid leukemia (AML) is characterized by the accumulation of immature blood cell precursors in the bone marrow. Pharmacologically overcoming the differentiation block in this condition is an attractive therapeutic avenue, which has achieved success only in a subtype of AML, acute promyelocytic leukemia (APL). Attempts to emulate this success in other AML subtypes have thus far been unsuccessful. Autophagy is a conserved protein degradation pathway with important roles in mammalian cell differentiation, particularly within the hematopoietic system. In the study described here, we investigated the functional importance of autophagy in APL cell differentiation. We found that autophagy is increased during all-trans-retinoic acid (ATRA)-induced granulocytic differentiation of the APL cell line NB4 and that this is associated with increased expression of LC3II and GATE-16 proteins involved in autophagosome formation. Autophagy inhibition, using either drugs (chloroquine/3-methyladenine) or short-hairpin RNA targeting the essential autophagy gene ATG7, attenuates myeloid differentiation. Importantly, we found that enhancing autophagy promotes ATRA-induced granulocytic differentiation of an ATRA-resistant derivative of the non-APL AML HL60 cell line (HL60-Diff-R). These data support the development of strategies to stimulate autophagy as a novel approach to promote differentiation in AML

    Phosphorylation of GFAP is associated with injury in the neonatal pig hypoxic-ischemic brain

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    Glial fibrillary acidic protein (GFAP) is an intermediate filament protein expressed in the astrocyte cytoskeleton that plays an important role in the structure and function of the cell. GFAP can be phosphorylated at six serine (Ser) or threonine (Thr) residues but little is known about the role of GFAP phosphorylation in physiological and pathophysiological states. We have generated antibodies against two phosphorylated GFAP (pGFAP) proteins: p8GFAP, where GFAP is phosphorylated at Ser-8 and p13GFAP, where GFAP is phosphorylated at Ser-13. We examined p8GFAP and p13GFAP expression in the control neonatal pig brain and at 24 and 72 h after an hypoxic-ischemic (HI) insult. Immunohistochemistry demonstrated pGFAP expression in astrocytes with an atypical cytoskeletal morphology, even in control brains. Semi-quantitative western blotting revealed that p8GFAP expression was significantly increased at 24 h post-insult in HI animals with seizures in frontal, parietal, temporal and occipital cortices. At 72 h post-insult, p8GFAP and p13GFAP expression were significantly increased in HI animals with seizures in brain regions that are vulnerable to cellular damage (cortex and basal ganglia), but no changes were observed in brain regions that are relatively spared following an HI insult (brain stem and cerebellum). Increased pGFAP expression was associated with poor neurological outcomes such as abnormal encephalography and neurobehaviour, and increased histological brain damage. Phosphorylation of GFAP may play an important role in astrocyte remodelling during development and disease and could potentially contribute to the plasticity of the central nervous system
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