13 research outputs found

    Positive relationships between association strength and phenotypic similarity characterize the assembly of mixed-species bird flocks worldwide

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    Competition theory predicts that local communities should consist of species that are more dissimilar than expected by chance. We find a strikingly different pattern in a multicontinent data set (55 presence-absence matrices from 24 locations) on the composition of mixed-species bird flocks, which are important sub-units of local bird communities the world over. By using null models and randomization tests followed by meta-analysis, we find the association strengths of species in flocks to be strongly related to similarity in body size and foraging behavior and higher for congeneric compared with noncongeneric species pairs. Given the local spatial scales of our individual analyses, differences in the habitat preferences of species are unlikely to have caused these association patterns; the patterns observed are most likely the outcome of species interactions. Extending group-living and social-information-use theory to a heterospecific context, we discuss potential behavioral mechanisms that lead to positive interactions among similar species in flocks, as well as ways in which competition costs are reduced. Our findings highlight the need to consider positive interactions along with competition when seeking to explain community assembly

    SARS-CoV-2 B.1.617.2 Delta variant replication and immune evasion

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    Abstract: The B.1.617.2 (Delta) variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was first identified in the state of Maharashtra in late 2020 and spread throughout India, outcompeting pre-existing lineages including B.1.617.1 (Kappa) and B.1.1.7 (Alpha)1. In vitro, B.1.617.2 is sixfold less sensitive to serum neutralizing antibodies from recovered individuals, and eightfold less sensitive to vaccine-elicited antibodies, compared with wild-type Wuhan-1 bearing D614G. Serum neutralizing titres against B.1.617.2 were lower in ChAdOx1 vaccinees than in BNT162b2 vaccinees. B.1.617.2 spike pseudotyped viruses exhibited compromised sensitivity to monoclonal antibodies to the receptor-binding domain and the amino-terminal domain. B.1.617.2 demonstrated higher replication efficiency than B.1.1.7 in both airway organoid and human airway epithelial systems, associated with B.1.617.2 spike being in a predominantly cleaved state compared with B.1.1.7 spike. The B.1.617.2 spike protein was able to mediate highly efficient syncytium formation that was less sensitive to inhibition by neutralizing antibody, compared with that of wild-type spike. We also observed that B.1.617.2 had higher replication and spike-mediated entry than B.1.617.1, potentially explaining the B.1.617.2 dominance. In an analysis of more than 130 SARS-CoV-2-infected health care workers across three centres in India during a period of mixed lineage circulation, we observed reduced ChAdOx1 vaccine effectiveness against B.1.617.2 relative to non-B.1.617.2, with the caveat of possible residual confounding. Compromised vaccine efficacy against the highly fit and immune-evasive B.1.617.2 Delta variant warrants continued infection control measures in the post-vaccination era

    31st Annual Meeting and Associated Programs of the Society for Immunotherapy of Cancer (SITC 2016) : part two

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    Background The immunological escape of tumors represents one of the main ob- stacles to the treatment of malignancies. The blockade of PD-1 or CTLA-4 receptors represented a milestone in the history of immunotherapy. However, immune checkpoint inhibitors seem to be effective in specific cohorts of patients. It has been proposed that their efficacy relies on the presence of an immunological response. Thus, we hypothesized that disruption of the PD-L1/PD-1 axis would synergize with our oncolytic vaccine platform PeptiCRAd. Methods We used murine B16OVA in vivo tumor models and flow cytometry analysis to investigate the immunological background. Results First, we found that high-burden B16OVA tumors were refractory to combination immunotherapy. However, with a more aggressive schedule, tumors with a lower burden were more susceptible to the combination of PeptiCRAd and PD-L1 blockade. The therapy signifi- cantly increased the median survival of mice (Fig. 7). Interestingly, the reduced growth of contralaterally injected B16F10 cells sug- gested the presence of a long lasting immunological memory also against non-targeted antigens. Concerning the functional state of tumor infiltrating lymphocytes (TILs), we found that all the immune therapies would enhance the percentage of activated (PD-1pos TIM- 3neg) T lymphocytes and reduce the amount of exhausted (PD-1pos TIM-3pos) cells compared to placebo. As expected, we found that PeptiCRAd monotherapy could increase the number of antigen spe- cific CD8+ T cells compared to other treatments. However, only the combination with PD-L1 blockade could significantly increase the ra- tio between activated and exhausted pentamer positive cells (p= 0.0058), suggesting that by disrupting the PD-1/PD-L1 axis we could decrease the amount of dysfunctional antigen specific T cells. We ob- served that the anatomical location deeply influenced the state of CD4+ and CD8+ T lymphocytes. In fact, TIM-3 expression was in- creased by 2 fold on TILs compared to splenic and lymphoid T cells. In the CD8+ compartment, the expression of PD-1 on the surface seemed to be restricted to the tumor micro-environment, while CD4 + T cells had a high expression of PD-1 also in lymphoid organs. Interestingly, we found that the levels of PD-1 were significantly higher on CD8+ T cells than on CD4+ T cells into the tumor micro- environment (p < 0.0001). Conclusions In conclusion, we demonstrated that the efficacy of immune check- point inhibitors might be strongly enhanced by their combination with cancer vaccines. PeptiCRAd was able to increase the number of antigen-specific T cells and PD-L1 blockade prevented their exhaus- tion, resulting in long-lasting immunological memory and increased median survival

    SARS-CoV-2 B.1.617.2 Delta variant replication and immune evasion.

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    The B.1.617.2 (Delta) variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was first identified in the state of Maharashtra in late 2020 and spread throughout India, outcompeting pre-existing lineages including B.1.617.1 (Kappa) and B.1.1.7 (Alpha)1. In vitro, B.1.617.2 is sixfold less sensitive to serum neutralizing antibodies from recovered individuals, and eightfold less sensitive to vaccine-elicited antibodies, compared with wild-type Wuhan-1 bearing D614G. Serum neutralizing titres against B.1.617.2 were lower in ChAdOx1 vaccinees than in BNT162b2 vaccinees. B.1.617.2 spike pseudotyped viruses exhibited compromised sensitivity to monoclonal antibodies to the receptor-binding domain and the amino-terminal domain. B.1.617.2 demonstrated higher replication efficiency than B.1.1.7 in both airway organoid and human airway epithelial systems, associated with B.1.617.2 spike being in a predominantly cleaved state compared with B.1.1.7 spike. The B.1.617.2 spike protein was able to mediate highly efficient syncytium formation that was less sensitive to inhibition by neutralizing antibody, compared with that of wild-type spike. We also observed that B.1.617.2 had higher replication and spike-mediated entry than B.1.617.1, potentially explaining the B.1.617.2 dominance. In an analysis of more than 130 SARS-CoV-2-infected health care workers across three centres in India during a period of mixed lineage circulation, we observed reduced ChAdOx1 vaccine effectiveness against B.1.617.2 relative to non-B.1.617.2, with the caveat of possible residual confounding. Compromised vaccine efficacy against the highly fit and immune-evasive B.1.617.2 Delta variant warrants continued infection control measures in the post-vaccination era

    Animais gordos e a dissolução da fronteira entre as espécies

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    Animais de estimação gordos costumavam ser, para muitas pessoas, engraçados e adoráveis; para algumas, os animaizinhos gordos (especialmente gatos) ainda o são: os quadrinhos de Garfield, sobre um gato acima do peso e preguiçoso, venderam bem; há sites e livros dedicados a exaltar a beleza e o encanto dos gatos gordos; e crianças anglófonas são socializadas por meio de livros de leitura fonológicos com títulos como Fat cat on a mat, associando o prazer de ler à fofura de animais de estimação rechonchudos. Tudo isto, no entanto, está mudando. Testemunhamos a transformação da obesidade de animais de estimação de fenômeno trivial ou preferência estética idiossincrática em problema social. Este vem mobilizando os meios de comunicação de massa, a opinião pública e ampla variedade de especialistas, além da intervenção de aparatos de Estado, como os tribunais e a polícia. Este artigo discute as maneiras pelas quais a obesidade ultrapassou a fronteira das espécies. Revisa as provas divulgadas para justificar as cada vez mais comuns - e cada vez mais estridentes - alegações de que estamos em meio a uma "epidemia" de obesidade de animais de estimação (algumas das quais afirmando que os animais de estimação acima do peso chegam a 60% do total), discute a fonte e avalia a credibilidade desta informação. Examina como a obesidade animal é apresentada na mídia por organizações de caridade, como Pet Club UK ou a RSPCA. E oferece reflexões sobre o que a preocupação corrente em relação à obesidade dos animais de estimação pode nos dizer a respeito das dimensões sociais, culturais, médicas, históricas, econômicas, emocionais e subjetivas da obesidade de maneira geral.<br>For many people, fat pets used to be cute, funny and adorable, and for some people fat pets (especially fat cats) still are: the Garfield comics, about an overweight, lazy cat, sell well, there are websites and books devoted to extolling the beauty and allure of fat cats, and children are socialized, through phonics readers with titles like Fat Cat on a Mat, to associate the pleasure of reading with the cuteness of round pets. All of this, however, is changing. We are witnessing the transformation of pet obesity from a trivial phenomenon or an idiosyncratic aesthetic preference into a social problem - one that increasingly mobilizes the mass media, public opinion and a wide variety of experts, and the intervention of state apparatuses like the courts and the police. This article discusses the ways in which obesity has crossed the species boundary. It reviews the evidence circulated to justify the increasingly common - and increasingly shrill - claims that we are in the midst of an "epidemic" of pet obesity (some claims assert that as many as 60% of all pets are overweight or obese) and it discusses the source and assesses the reliability of that evidence. It examines how pet obesity is presented in the mass media and by charitable organizations like Pet Club UK or the RSPCA. It also offers some thoughts about what current concerns about pet obesity can tell us about the social, cultural, medical, historical, economic, emotional and subjective dimensions of obesity more generally

    Enhancing and Measuring Consumers’ Motivation, Opportunity, and Ability to Process Brand Information from Ads

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    Network science in clinical trials: A patient-centered approach

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