2,388 research outputs found

    Predator avoidance in extremophile fish

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    Extreme habitats are often characterized by reduced predation pressures, thus representing refuges for the inhabiting species. The present study was designed to investigate predator avoidance of extremophile populations of Poecilia mexicana and P. sulphuraria that either live in hydrogen sulfide-rich (sulfidic) springs or cave habitats, both of which are known to have impoverished piscine predator regimes. Focal fishes that inhabited sulfidic springs showed slightly weaker avoidance reactions when presented with several naturally occurring predatory cichlids, but strongest differences to populations from non-sulfidic habitats were found in a decreased shoaling tendency with non-predatory swordtail (Xiphophorus hellerii) females. When comparing avoidance reactions between P. mexicana from a sulfidic cave (Cueva del Azufre) and the adjacent sulfidic surface creek (El Azufre), we found only slight differences in predator avoidance, but surface fish reacted much more strongly to the non-predatory cichlid Vieja bifasciata. Our third experiment was designed to disentangle learned from innate effects of predator recognition. We compared laboratory-reared (i.e., predator-naïve) and wild-caught (i.e., predator-experienced) individuals of P. mexicana from a non-sulfidic river and found no differences in their reaction towards the presented predators. Overall, our results indicate (1) that predator avoidance is still functional in extremophile Poecilia spp. and (2) that predator recognition and avoidance reactions have a strong genetic basis

    Patients’ self‐reported physical and psychological effects of opioid use in chronic noncancer pain—A retrospective cross‐sectional analysis

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    Background: Strong opioids can have unintended effects. Clinical studies of strong opioids mainly report physical side effects, psychiatric or opioid use disorders. To date, too little attention has been paid to the psychological effects of opioids to treat patients with chronic noncancer pain (CNCP). This study aims to identify and measure (i) the nature and frequency of physical and psychological effects and (ii) the degree of physician counseling of patients with CNCP taking strong opioids. Methods: Within a cross-sectional survey-conducted as part of a randomised controlled online intervention trial (ERONA [Experiencing the risk of overusing opioids among patients with chronic non-cancer pain in ambulatory care])-300 German CNCP patients were surveyed via patient-reported outcome measures regarding on both the side effects from their use of strong opioids as well as their counselling experience. Results: Among the patients' reported effects, the psychological outcomes of the opioids in CNCP were: feeling relaxed (84%), fatigue (76%), dizziness (57%), listlessness (37%), difficulty with mental activities (23%), dulled emotions (17%) and poor memory (17%). Ninety-two per cent of the patients reported having received information about opioid effects, and 46% had discussed cessation of the opioid medication with their physicians before commencing the prescription. Conclusions: In addition to the well-known physical side effects, patients with CNCP taking strong opioids experience significant psychological effects. In view of these effects, discontinuation of opioid therapy should be discussed early to ensure their benefits do not outweigh their harm. Significance: In this study, patients with non-cancer pain notice that opioids they have taken do not only cause physical side effects but also may have an impact on their psyche and their emotions and, thus, may also affect quality of life substantially. Clinical trial number: DRKS00020358

    CD171- and GD2-specific CAR-T cells potently target retinoblastoma cells in preclinical in vitro testing

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    BACKGROUND: Chimeric antigen receptor (CAR)-based T cell therapy is in early clinical trials to target the neuroectodermal tumor, neuroblastoma. No preclinical or clinical efficacy data are available for retinoblastoma to date. Whereas unilateral intraocular retinoblastoma is cured by enucleation of the eye, infiltration of the optic nerve indicates potential diffuse scattering and tumor spread leading to a major therapeutic challenge. CAR-T cell therapy could improve the currently limited therapeutic strategies for metastasized retinoblastoma by simultaneously killing both primary tumor and metastasizing malignant cells and by reducing chemotherapy-related late effects. METHODS: CD171 and GD2 expression was flow cytometrically analyzed in 11 retinoblastoma cell lines. CD171 expression and T cell infiltration (CD3+) was immunohistochemically assessed in retrospectively collected primary retinoblastomas. The efficacy of CAR-T cells targeting the CD171 and GD2 tumor-associated antigens was preclinically tested against three antigen-expressing retinoblastoma cell lines. CAR-T cell activation and exhaustion were assessed by cytokine release assays and flow cytometric detection of cell surface markers, and killing ability was assessed in cytotoxic assays. CAR constructs harboring different extracellular spacer lengths (short/long) and intracellular co-stimulatory domains (CD28/4-1BB) were compared to select the most potent constructs. RESULTS: All retinoblastoma cell lines investigated expressed CD171 and GD2. CD171 was expressed in 15/30 primary retinoblastomas. Retinoblastoma cell encounter strongly activated both CD171-specific and GD2-specific CAR-T cells. Targeting either CD171 or GD2 effectively killed all retinoblastoma cell lines examined. Similar activation and killing ability for either target was achieved by all CAR constructs irrespective of the length of the extracellular spacers and the co-stimulatory domain. Cell lines differentially lost tumor antigen expression upon CAR-T cell encounter, with CD171 being completely lost by all tested cell lines and GD2 further down-regulated in cell lines expressing low GD2 levels before CAR-T cell challenge. Alternating the CAR-T cell target in sequential challenges enhanced retinoblastoma cell killing. CONCLUSION: Both CD171 and GD2 are effective targets on human retinoblastoma cell lines, and CAR-T cell therapy is highly effective against retinoblastoma in vitro. Targeting of two different antigens by sequential CAR-T cell applications enhanced tumor cell killing and preempted tumor antigen loss in preclinical testing

    Molecular Characterization of a Novel Staphylococcus Aureus Surface Protein (SasC) Involved in Cell Aggregation and Biofilm Accumulation

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    BACKGROUND:Staphylococci belong to the most important pathogens causing implant-associated infections. Colonization of the implanted medical devices by the formation of a three-dimensional structure made of bacteria and host material called biofilm is considered the most critical factor in these infections. To form a biofilm, bacteria first attach to the surface of the medical device, and then proliferate and accumulate into multilayered cell clusters. Biofilm accumulation may be mediated by polysaccharide and protein factors. METHODOLOGY/PRINCIPAL FINDINGS:The information on Staphylococcus aureus protein factors involved in biofilm accumulation is limited, therefore, we searched the S. aureus Col genome for LPXTG-motif containing potential surface proteins and chose the so far uncharacterized S. aureus surface protein C (SasC) for further investigation. The deduced SasC sequence consists of 2186 amino acids with a molecular mass of 238 kDa and has features typical of gram-positive surface proteins, such as an N-terminal signal peptide, a C-terminal LPXTG cell wall anchorage motif, and a repeat region consisting of 17 repeats similar to the domain of unknown function 1542 (DUF1542). We heterologously expressed sasC in Staphylococcus carnosus, which led to the formation of huge cell aggregates indicative of intercellular adhesion and biofilm accumulation. To localize the domain conferring cell aggregation, we expressed two subclones of sasC encoding either the N-terminal domain including a motif that is found in various architectures (FIVAR) or 8 of the DUF1542 repeats. SasC or its N-terminal domain, but not the DUF1542 repeat region conferred production of huge cell aggregates, higher attachment to polystyrene, and enhanced biofilm formation to S. carnosus and S. aureus. SasC does not mediate binding to fibrinogen, thrombospondin-1, von Willebrand factor, or platelets as determined by flow cytometry. CONCLUSIONS/SIGNIFICANCE:Thus, SasC represents a novel S. aureus protein factor involved in cell aggregation and biofilm formation, which may play an important role in colonization during infection with this important pathogen

    Barriers to SARS-CoV-2 Testing among U.S. Employers in the COVID-19 Pandemic: A Qualitative Analysis Conducted January through April 2021

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    During the first year of the COVID-19 pandemic, U.S. companies were seeking ways to support their employees to return to the workplace. Nonetheless, the development of strategies to support the access, use, and interpretation of SARS-CoV-2 testing was challenging. In the present study, we explore, from the perspective of owners and company leadership, the barriers to SARSCoV-2 testing among U.S. companies. Key informant interviews with company representatives were conducted during January--April 2021 about SARS-CoV-2 testing. A pre-interview survey assessed respondent socio-demographic and organizational characteristics. Interview sessions were transcribed, coded, and analyzed using MaxQDA. A total of twenty interviews were completed with at least two interviews conducted in each major U.S. industry sector. Ninety percent of participants represented companies in business \u3e10 years, comprising both small and large workforces. Using a grounded theory approach, six themes emerged: (1) access to and knowledge of SARS-CoV-2 tests; (2) strategies for symptomatic and asymptomatic testing of workers; (3) type/availability of personal protective equipment to mitigate coronavirus exposures; (4) return-to-work policies; (5) guidance and communication of SARS-CoV-2 Testing; and (6) use of contact tracing and SARS-CoV-2 vaccination. Various modifiable and non-modifiable challenges for SARS-CoV-2 testing among U.S. companies were identified and can inform work-related SARS-CoV-2 testing strategies

    DoInG - Informatisches Denken und Handeln in der Grundschule

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    Anfang der 2000er Jahre machte das Schlagwort „Digital Natives“ [1] auch in populärwissenschaftlichen Artikeln die Runde. Die in diesem Begriff mitschwingende Implikation, dass die ‚Ureinwohner’ des digitalen Zeitalters über weitreichendere Kenntnisse der Computertechnik verfügen als Menschen, die sich in das Gebiet der Informatik erst später eingearbeitet haben, wird inzwischen kritisiert: Computertechnik wird von ‚Digital Natives’ zumeist nur genutzt, die dahinterliegenden informationstechnischen Abläufe werden aber in der Regel häufig nicht verstanden [2] und auch nicht hinterfragt. Nicht nur aus Gründen der wirtschaftlichen Wettbewerbsfähigkeit sollte sich dies ändern. Die Bemühungen um informatische Bildung in den entsprechenden Schulfächern scheinen dazu aber nicht auszureichen, und es gibt Hinweise darauf, dass die Begegnung mit Informatik erst in der Sekundarstufe für viele Schülerinnen und Schüler zu spät ansetzt. Von verschiedenen Seiten – sowohl aus wissenschaftlicher [3] als auch aus wirtschaftlicher [4] Perspektive – wird daher nun vermehrt gefordert, informatische Bildung bereits in den Grundschulunterricht zu implementieren. Dabei soll es neben der Nutzung von Computern vor allem um Interessenentwicklung und ein basales Verständnis der dahinterliegenden Prozesse gehen – ein Vorhaben, das in einigen anderen Ländern bereits umgesetzt wird [5].Im Gemeinschaftsprojekt ‚DoInG – Informatisches Denken und Handeln in der Grundschule’ des Arbeitsbereichs Sachunterricht, der Didaktik der Informatik, der Informatik und der Didaktik der Physik an der Freien Universität Berlin soll ein praxistaugliches Konzept entwickelt werden, das diesen Forderungen nachkommt. Der Beitrag stellt die dem Projekt zugrunde liegende theoretische und empirische Basis vor

    Working landscapes need at least 20% native habitat

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    International agreements aim to conserve 17% of Earth's land area by 2020 but include no area‐based conservation targets within the working landscapes that support human needs through farming, ranching, and forestry. Through a review of country‐level legislation, we found that just 38% of countries have minimum area requirements for conserving native habitats within working landscapes. We argue for increasing native habitats to at least 20% of working landscape area where it is below this minimum. Such target has benefits for food security, nature's contributions to people, and the connectivity and effectiveness of protected area networks in biomes in which protected areas are underrepresented. We also argue for maintaining native habitat at higher levels where it currently exceeds the 20% minimum, and performed a literature review that shows that even more than 50% native habitat restoration is needed in particular landscapes. The post‐2020 Global Biodiversity Framework is an opportune moment to include a minimum habitat restoration target for working landscapes that contributes to, but does not compete with, initiatives for expanding protected areas, the UN Decade on Ecosystem Restoration (2021–2030) and the UN Sustainable Development Goals
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