132 research outputs found

    Herausforderungen transdisziplinären Arbeitens im Reallabor „Wissensdialog Nordschwarzwald“

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    Das Reallabor „Wissensdialog Nordschwarzwald“ ist eng an den Nationalpark Schwarzwald gekoppelt: Wie lassen sich Chancen nutzen, die der Nationalpark für die nachhaltige Entwicklung der Region bietet? Was lässt sich aus den im Nationalparkgebiet stattfindenden ökologischen Prozessen lernen? Dies sind die zentralen Forschungsfragen des Projekts. Der vorliegende Beitrag stellt die Herausforderungen des spezifischen transdisziplinären Designs des Reallabors in den Vordergrund. Basierend auf Interviews mit Projektbeteiligten, dem Austausch in Projektgremien und eigenen Beobachtungen reflektieren die AutorInnen zentrale Designelemente sowie Kontextbedingungen des Projektes. Angesichts der besonderen Gegebenheiten des ländlichen Raumes postulieren sie den Bedarf, eine stärker an diesen angepasste Reallaborforschung zu entwickeln.The Real-world Laboratory “Knowledge Dialogue Northern Black Forest” is closely linked to the Black Forest National Park in Baden-Württemberg, Germany: How can one actually take advantage of the opportunities a national park offers for regional transformation towards sustainability, and what can be learnt from ecological processes in the park area? These are the project’s core questions. The following article focuses on the transdisciplinary project design and its challenges. Based on interviews with project members, discussions within project committees and own observations, the authors reflect on essential design elements and context conditions of the project. On this basis, they postulate a need for better adapting the real-world laboratory research to the specific conditions of rural areas

    Pesquisa de leucócitos residuais

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    A presença de leucócitos nos concentrados de eritrócitos (CE) e nos concentrados de plaquetas (CP) está associada a uma maior incidência de reacções febris, com transmissão de citomegalovírus (CMV) e aloimunização a antigénios HLA em indivíduos transfundidos. A exigência de componentes sanguíneos pobres em leucócitos implica a existência de um controlo relativamente à persistência dos leucócitos residuais. As amostras foram adquiridas no citómetro de fluxo e analisadas mediante um programa informático. A citometria de fluxo permite quantificar os leucócitos residuais dos diferentes componentes sanguíneos, avaliando a conformidade ou não conformidade com as normas exigidas pelo conselho da Europa

    Loss of SMAD4 Is Associated With Poor Tumor Immunogenicity and Reduced PD-L1 Expression in Pancreatic Cancer

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    Transforming Growth Factor β (TGFβ) is a key mediator of immune evasion in pancreatic ductal adenocarcinoma (PDAC), and the addition of TGFβ inhibitors in select immunotherapy regimens shows early promise. Though the TGFβ target SMAD4 is deleted in approximately 55% of PDAC tumors, the effects of SMAD4 loss on tumor immunity have yet to be fully explored. Using a combination of genomic databases and PDAC specimens, we found that tumors with loss of SMAD4 have a comparatively poor T-cell infiltrate. SMAD4 loss was also associated with a reduction in several chemokines with known roles in T-cell recruitment, which was recapitulated using knockdown of SMAD4 in PDAC cell lines. Accordingly, JURKAT T-cells were poorly attracted to conditioned media from PDAC cells with knockdown of SMAD4 and lost their ability to produce IFNγ. However, while exogenous TGFβ modestly reduced PD-L1 expression in SMAD4-intact cell lines, SMAD4 and PD-L1 positively correlated in human PDAC samples. PD-L1 status was closely related to tumor-infiltrating lymphocytes, particularly IFNγ-producing T-cells, which were more abundant in SMAD4-expressing tumors. Low concentrations of IFNγ upregulated PD-L1 in tumor cells in vitro, even when administered alongside high concentrations of TGFβ. Hence, while SMAD4 may have a modest inhibitory effect on PD-L1 in tumor cells, SMAD4 indirectly promotes PD-L1 expression in the pancreatic tumor microenvironment by enhancing T-cell infiltration and IFNγ biosynthesis. These data suggest that pancreatic cancers with loss of SMAD4 represent a poorly immunogenic disease subtype, and SMAD4 status warrants further exploration as a predictive biomarker for cancer immunotherapy

    Accounting for variability when resurrecting dormant propagules substantiates their use in eco-evolutionary studies

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    There has been a steady rise in the use of dormant propagules to study biotic responses to environmental change over time. This is particularly important for organisms that strongly mediate ecosystem processes, as changes in their traits over time can provide a unique snapshot into the structure and function of ecosystems from decades to millennia in the past. Understanding sources of bias and variation is a challenge in the field of resurrection ecology, including those that arise because often-used measurements like seed germination success are imperfect indicators of propagule viability. Using a Bayesian statistical framework, we evaluated sources of variability and tested for zero-inflation and overdispersion in data from 13 germination trials of soil-stored seeds of Schoenoplectus americanus, an ecosystem engineer in coastal salt marshes in the Chesapeake Bay. We hypothesized that these two model structures align with an ecological understanding of dormancy and revival: zero-inflation could arise due to failed germinations resulting from inviability or failed attempts to break dormancy, and overdispersion could arise by failing to measure important seed traits. A model that accounted for overdispersion, but not zero-inflation, was the best fit to our data. Tetrazolium viability tests corroborated this result: most seeds that failed to germinate did so because they were inviable, not because experimental methods failed to break their dormancy. Seed viability declined exponentially with seed age and was mediated by seed provenance and experimental conditions. Our results provide a framework for accounting for and explaining variability when estimating propagule viability from soil-stored natural archives which is a key aspect of using dormant propagules in eco-evolutionary studies

    Transmission of Vibrio cholerae Is Antagonized by Lytic Phage and Entry into the Aquatic Environment

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    Cholera outbreaks are proposed to propagate in explosive cycles powered by hyperinfectious Vibrio cholerae and quenched by lytic vibriophage. However, studies to elucidate how these factors affect transmission are lacking because the field experiments are almost intractable. One reason for this is that V. cholerae loses the ability to culture upon transfer to pond water. This phenotype is called the active but non-culturable state (ABNC; an alternative term is viable but non-culturable) because these cells maintain the capacity for metabolic activity. ABNC bacteria may serve as the environmental reservoir for outbreaks but rigorous animal studies to test this hypothesis have not been conducted. In this project, we wanted to determine the relevance of ABNC cells to transmission as well as the impact lytic phage have on V. cholerae as the bacteria enter the ABNC state. Rice-water stool that naturally harbored lytic phage or in vitro derived V. cholerae were incubated in a pond microcosm, and the culturability, infectious dose, and transcriptome were assayed over 24 h. The data show that the major contributors to infection are culturable V. cholerae and not ABNC cells. Phage did not affect colonization immediately after shedding from the patients because the phage titer was too low. However, V. cholerae failed to colonize the small intestine after 24 h of incubation in pond water—the point when the phage and ABNC cell titers were highest. The transcriptional analysis traced the transformation into the non-infectious ABNC state and supports models for the adaptation to nutrient poor aquatic environments. Phage had an undetectable impact on this adaptation. Taken together, the rise of ABNC cells and lytic phage blocked transmission. Thus, there is a fitness advantage if V. cholerae can make a rapid transfer to the next host before these negative selective pressures compound in the aquatic environment

    The search for the 'next' euphoric non-fentanil novel synthetic opioids on the illicit drugs market: current status and horizon scanning

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    Purpose: A detailed review on the chemistry and pharmacology of non-fentanil novel synthetic opioid receptor agonists, particularly N-substituted benzamides and acetamides (known colloquially as U-drugs) and 4-aminocyclohexanols, developed at the Upjohn Company in the 1970s and 1980s is presentedMethod: Peer-reviewed literature, patents, professional literature, data from international early warning systems and drug user fora discussion threads have been used to track their emergence as substances of abuse.Results: In terms of impact on drug markets, prevalence and harm, the most significant compound of this class to date has been U-47700 (trans-3,4-dichloro-N-[2-(dimethylamino)cyclohexyl]-N-methylbenzamide), reported by users to give short-lasting euphoric effects and a desire to re-dose. Since U-47700 was internationally controlled in 2017, a range of related compounds with similar chemical structures, adapted from the original patented compounds, have appeared on the illicit drugs market. Interest in a structurally unrelated opioid developed by the Upjohn Company and now known as BDPC/bromadol appears to be increasing and should be closely monitored.Conclusions: International early warning systems are an essential part of tracking emerging psychoactive substances and allow responsive action to be taken to facilitate the gathering of relevant data for detailed risk assessments. Pre-emptive research on the most likely compounds to emerge next, so providing drug metabolism and pharmacokinetic data to ensure that new substances are detected early in toxicological samples is recommended. As these compounds are chiral compounds and stereochemistry has a large effect on their potency, it is recommended that detection methods consider the determination of configuration
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