ESTABELECIMENTO IN VITRO DE GEMAS AXILARES DE ABACAXIZEIRO EM FUNÇÃO DA VARIAÇÃO DA CONCENTRAÇÃO DE 6-BENZILAMINOPURINA

A micropropagação é uma técnica da cultura de tecidos vegetais que se destaca na obtenção de plantas saudáveis, aplicada com sucesso na produção em larga escala de variedades comercias de abacaxi. No entanto, estudos com variedades selvagens do gênero Ananas apresentaram baixas taxas de multiplicação. Sendo assim, o objetivo desta pesquisa foi avaliar o efeito da variação da concentração de 6-benzilaminopurina (BAP) no estabelecimento in vitro de gemas axilares de Ananas comosus cv. Pérola. Foram avaliados seis tratamentos, sendo eles: MS isento de reguladores (T1); 0,0 (T2); 0,025 (T3); 0,05 (T4); 0,1 (T5); 0,2 mg L-1 de BAP (T6), combinados com 0,01 mg L-1 de ácido naftalenoacético (ANA). O experimento foi conduzido em delineamento inteiramente casualizado, contendo dezesseis repetições por tratamento, cuja unidade experimental foi constituída de um explante por tubo de ensaio.  Os tratamentos 2, 3, 4 e 5 atingiram o estabelecimento máximo com 21 dias de cultivo in vitro, enquanto o tratamento 1 não obteve o estabelecimento máximo e o tratamento 6 obteve apenas aos 37 dias de cultivo. Sendo assim, nota-se que concentrações de BAP entre 0,025 a 0,1 mg L-1 aceleram o estabelecimento de gemas axilares de abacaxi e, em contrapartida, a ausência de reguladores de crescimento ou altas concentrações de BAP interferem negativamente no seu estabelecimento in vitro. A variação da concentração de 6-benzilaminopurina (BAP) não influenciou no número de explantes estabelecidos in vitro após 37 dias de cultivo. Na ausência de regulador de crescimento vegetal há baixa taxa de brotações dos explantes.PALAVRAS-CHAVE: Cultura in vitro, Micropropagação, Reguladores de crescimento

Elm1 kinase activates the spindle position checkpoint kinase Kin4

Elm1 phosphorylates a conserved residue within the Kin4 kinase domain to coordinate spindle position with cell cycle progression

Endophytic fungi from the Amazonian plant Paullinia cupana and from Olea europaea isolated using cassava as an alternative starch media source

Endophytic fungi live inside plants, apparently do not cause any harm to their hosts and may play important roles in defense and growth promotion. Fungal growth is a routine practice at microbiological laboratories, and the Potato Dextrose Agar (PDA) is the most frequently used medium because it is a rich source of starch. However, the production of potatoes in some regions of the world can be costly. Aiming the development of a new medium source to tropical countries, in the present study, we used leaves from the guarana (a tropical plant from the Amazon region) and the olive (which grows in subtropical and temperate regions) to isolate endophytic fungi using PDA and Manihot Dextrose Agar (MDA). Cassava (Manihot esculenta) was evaluated as a substitute starch source. For guarana, the endophytic incidence (EI) was 90% and 98% on PDA and MDA media, respectively, and 65% and 70% for olive, respectively. The fungal isolates were sequenced using the ITS- rDNA region. The fungal identification demonstrated that the isolates varied according to the host plant and media source. In the guarana plant, 13 fungal genera were found using MDA and six were found using PDA. In the olive plant, six genera were obtained using PDA and 4 were obtained using MDA. The multivariate analysis results demonstrated the highest fungal diversity from guarana when using MDA medium. Interestingly, some genera were isolated from one specific host or in one specific media, suggesting the importance of these two factors in fungal isolation specificity. Thus, this study indicated that cassava is a feasible starch source that could serve as a potential alternative medium to potato medium.This work was supported by a grant from the Foundation for Research Assistance, São Paulo State and Amazon State, Brazil (grant n. 2009/53376-2) and by the National Council for Scientific and Technological Development (CNPq). We thank FAPESP for the M.C.Q. (grant no. 2010/50445-0), J.M. (grant no. 2011/18740-5) and S.T. (grant no. 2010/15192-4) and CNPq for E.F.S. and D.M.L. fellowships

Budding Yeast Dma Proteins Control Septin Dynamics and the Spindle Position Checkpoint by Promoting the Recruitment of the Elm1 Kinase to the Bud Neck

The first step towards cytokinesis in budding yeast is the assembly of a septin ring at the future site of bud emergence. Integrity of this ring is crucial for cytokinesis, proper spindle positioning, and the spindle position checkpoint (SPOC). This checkpoint delays mitotic exit and cytokinesis as long as the anaphase spindle does not properly align with the division axis. SPOC signalling requires the Kin4 protein kinase and the Kin4-regulating Elm1 kinase, which also controls septin dynamics. Here, we show that the two redundant ubiquitin-ligases Dma1 and Dma2 control septin dynamics and the SPOC by promoting the efficient recruitment of Elm1 to the bud neck. Indeed, dma1 dma2 mutant cells show reduced levels of Elm1 at the bud neck and Elm1-dependent activation of Kin4. Artificial recruitment of Elm1 to the bud neck of the same cells is sufficient to re-establish a normal septin ring, proper spindle positioning, and a proficient SPOC response in dma1 dma2 cells. Altogether, our data indicate that septin dynamics and SPOC function are intimately linked and support the idea that integrity of the bud neck is crucial for SPOC signalling

ICAR: endoscopic skull‐base surgery

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Socializing One Health: an innovative strategy to investigate social and behavioral risks of emerging viral threats

In an effort to strengthen global capacity to prevent, detect, and control infectious diseases in animals and people, the United States Agency for International Development’s (USAID) Emerging Pandemic Threats (EPT) PREDICT project funded development of regional, national, and local One Health capacities for early disease detection, rapid response, disease control, and risk reduction. From the outset, the EPT approach was inclusive of social science research methods designed to understand the contexts and behaviors of communities living and working at human-animal-environment interfaces considered high-risk for virus emergence. Using qualitative and quantitative approaches, PREDICT behavioral research aimed to identify and assess a range of socio-cultural behaviors that could be influential in zoonotic disease emergence, amplification, and transmission. This broad approach to behavioral risk characterization enabled us to identify and characterize human activities that could be linked to the transmission dynamics of new and emerging viruses. This paper provides a discussion of implementation of a social science approach within a zoonotic surveillance framework. We conducted in-depth ethnographic interviews and focus groups to better understand the individual- and community-level knowledge, attitudes, and practices that potentially put participants at risk for zoonotic disease transmission from the animals they live and work with, across 6 interface domains. When we asked highly-exposed individuals (ie. bushmeat hunters, wildlife or guano farmers) about the risk they perceived in their occupational activities, most did not perceive it to be risky, whether because it was normalized by years (or generations) of doing such an activity, or due to lack of information about potential risks. Integrating the social sciences allows investigations of the specific human activities that are hypothesized to drive disease emergence, amplification, and transmission, in order to better substantiate behavioral disease drivers, along with the social dimensions of infection and transmission dynamics. Understanding these dynamics is critical to achieving health security--the protection from threats to health-- which requires investments in both collective and individual health security. Involving behavioral sciences into zoonotic disease surveillance allowed us to push toward fuller community integration and engagement and toward dialogue and implementation of recommendations for disease prevention and improved health security