2,071 research outputs found
Direito de autor e redes sociais digitais na sociedade em rede
O sistema de proteção do direito de autor como se apresenta em nossa legislação foi concebido a partir da noção moderna de autor, que pouco se parece com o autor contemporâneo. A sociedade em rede mudou, entre tantas outras coisas, a forma como se faz e se consome cultura. O espectador, através das facilidades proporcionadas por dispositivos e aplicações conectados à internet, tornou-se também autor. A obra, além de ressignificada, é reapropriada pela sociedade de onde veio a inspiração do autor. Partindo disso, entende-se que a tutela do direito de autor até pode prestigiar seu esforço através de remuneração apropriada, mas o legislador deve cuidar para que tal proteção não inviabilize outros usos da obra, em especial aqueles que potencializam o desenvolvimento da sociedade como a educação
First Emergence of Resistance to Macrolides and Tetracycline Identified in Mannheimia haemolytica and Pasteurella multocida Isolates from Beef Feedlots in Australia
Bovine respiratory disease (BRD) causes high morbidity and mortality in beef cattle worldwide. Antimicrobial resistance (AMR) monitoring of BRD pathogens is critical to promote appropriate antimicrobial stewardship in veterinary medicine for optimal treatment and control. Here, the susceptibility of Mannheimia haemolytica and Pasteurella multicoda isolates obtained from BRD clinical cases (deep lung swabs at post-mortem) among feedlots in four Australian states (2014-2019) was determined for 19 antimicrobial agents. The M. haemolytica isolates were pan-susceptible to all tested agents apart from a single macrolide-resistant isolate (1/88; 1.1%) from New South Wales (NSW). Much higher frequencies of P. multocida isolates were resistant to tetracycline (18/140; 12.9%), tilmicosin (19/140; 13.6%), tulathromycin/gamithromycin (17/140; 12.1%), and ampicillin/penicillin (6/140; 4.6%). Five P. multocida isolates (3.6%), all obtained from NSW in 2019, exhibited dual resistance to macrolides and tetracycline, and a further two Queensland isolates from 2019 (1.4%) exhibited a multidrug-resistant phenotype to ampicillin/penicillin, tetracycline, and tilmicosin. Random-amplified polymorphic DNA (RAPD) typing identified a high degree of genetic homogeneity among the M. haemolytica isolates, whereas P. multocida isolates were more heterogeneous. Illumina whole genome sequencing identified the genes msr(E) and mph(E)encoding macrolide resistance, tet(R)-tet(H) or tet(Y) encoding tetracycline resistance, and blaROB-1 encoding ampicillin/penicillin resistance in all isolates exhibiting a corresponding resistant phenotype. The exception was the tilmicosin-resistant, tulathromycin/gamithromycin-susceptible phenotype identified in two Queensland isolates, the genetic basis of which could not be determined. These results confirm the first emergence of AMR in M. haemolytica and P. multocida from BRD cases in Australia, which should be closely monitored
B Cells Regulate Neutrophilia during Mycobacterium tuberculosis Infection and BCG Vaccination by Modulating the Interleukin-17 Response
We have previously demonstrated that B cells can shape the immune response to Mycobacterium tuberculosis, including the level of neutrophil infiltration and granulomatous inflammation at the site of infection. The present study examined the mechanisms by which B cells regulate the host neutrophilic response upon exposure to mycobacteria and how neutrophilia may influence vaccine efficacy. To address these questions, a murine aerosol infection tuberculosis (TB) model and an intradermal (ID) ear BCG immunization mouse model, involving both the μMT strain and B cell-depleted C57BL/6 mice, were used. IL (interleukin)-17 neutralization and neutrophil depletion experiments using these systems provide evidence that B cells can regulate neutrophilia by modulating the IL-17 response during M. tuberculosis infection and BCG immunization. Exuberant neutrophilia at the site of immunization in B cell-deficient mice adversely affects dendritic cell (DC) migration to the draining lymph nodes and attenuates the development of the vaccine-induced Th1 response. The results suggest that B cells are required for the development of optimal protective anti-TB immunity upon BCG vaccination by regulating the IL-17/neutrophilic response. Administration of sera derived from M. tuberculosis-infected C57BL/6 wild-type mice reverses the lung neutrophilia phenotype in tuberculous μMT mice. Together, these observations provide insight into the mechanisms by which B cells and humoral immunity modulate vaccine-induced Th1 response and regulate neutrophila during M. tuberculosis infection and BCG immunization. © 2013 Kozakiewicz et al
IFNγ production in peripheral blood of early Lyme disease patients to hLFAα(L) (aa326-345)
BACKGROUND: It has been proposed that outer surface protein A (OspA) of Borrelia burgdorferi sensu stricto contains a T helper 1 (Th1) cell epitope that could play a role in an autoimmune response to hLFA1. METHODS: We used two peptides, hLFAα(L) (aa326-345) and Borrelia burgdorferi OspAB31 (aa164-183), as stimulating antigens to measure Th1 proinflammatory IFNγ cytokine production in peripheral blood of Lyme disease patients presenting with EM without history of arthritis, as well as in peripheral blood of healthy individuals. RESULTS: IFNγ responses to hLFA1 peptide were observed in 11 of 19 Lyme disease patients and in 3 of 15 healthy controls. In contrast, only 2 of 19 of the Lyme disease patients and none of the controls responded to the homologous OspAB31 peptide. CONCLUSIONS: IFNγ was produced in response to stimulation with peptide hLFAα(L) (aa326-345) in peripheral blood of 58% of patients with early Lyme disease without signs of arthritis, as well as in peripheral blood of 20% of healthy individuals, but not in response to stimulation with the homologous OspAB31 (aa164-183) peptide (p < 0.05). Our results suggest that reactivity to the hLFA1 peptide in peripheral blood may be the result of T cell degeneracy
Morphological Characters of the Thickbody Skate Amblyraja frerichsi (Krefft 1968) (Rajiformes: Rajidae), with Notes on Its Biology
Detailed descriptions of morphological features, morphometrics, neurocranium anatomy, clasper structure and egg case descriptions are provided for the thickbody skate Amblyraja frerichsi; a rare, deep-water species from Chile, Argentina and Falkland Islands. The species diagnosis is complemented from new observations and aspects such as colour, size and distribution are described. Geographic and bathymetric distributional ranges are discussed as relevant features of this taxońs biology. Additionally, the conservation status is assessed including bycatch records from Chilean fisheries
Are Nested Networks More Robust to Disturbance? A Test Using Epiphyte-Tree, Comensalistic Networks
Recent research on ecological networks suggests that mutualistic networks are
more nested than antagonistic ones and, as a result, they are more robust
against chains of extinctions caused by disturbances. We evaluate whether
mutualistic networks are more nested than comensalistic and antagonistic
networks, and whether highly nested, host-epiphyte comensalistic networks fit
the prediction of high robustness against disturbance. A review of 59 networks
including mutualistic, antagonistic and comensalistic relationships showed that
comensalistic networks are significantly more nested than antagonistic and
mutualistic networks, which did not differ between themselves. Epiphyte-host
networks from old-growth forests differed from those from disturbed forest in
several topological parameters based on both qualitative and quantitative
matrices. Network robustness increased with network size, but the slope of this
relationship varied with nestedness and connectance. Our results indicate that
interaction networks show complex responses to disturbances, which influence
their topology and indirectly affect their robustness against species
extinctions
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