Glycogen Synthase Kinase 3 (GSK3) Inhibitor, SB-216763, Promotes Pluripotency in Mouse Embryonic Stem Cells

Canonical Wnt/β-catenin signaling has been suggested to promote self-renewal of pluripotent mouse and human embryonic stem cells. Here, we show that SB-216763, a glycogen synthase kinase-3 (GSK3) inhibitor, can maintain mouse embryonic stem cells (mESCs) in a pluripotent state in the absence of exogenous leukemia inhibitory factor (LIF) when cultured on mouse embryonic fibroblasts (MEFs). MESCs maintained with SB-216763 for one month were morphologically indistinguishable from LIF-treated mESCs and expressed pluripotent-specific genes Oct4, Sox2, and Nanog. Furthermore, Nanog immunostaining was more homogenous in SB-216763-treated colonies compared to LIF. Embryoid bodies (EBs) prepared from these mESCs expressed early-stage markers for all three germ layers, and could efficiently differentiate into cardiac-like cells and MAP2-immunoreactive neurons. To our knowledge, SB-216763 is the first GSK3 inhibitor that can promote self-renewal of mESC co-cultured with MEFs for more than two months

Research on information systems failures and successes: Status update and future directions

The final publication is available at Springer via http://dx.doi.org/10.1007/s10796-014-9500-yInformation systems success and failure are among the most prominent streams in IS research. Explanations of why some IS fulfill their expectations, whereas others fail, are complex and multi-factorial. Despite the efforts to understand the underlying factors, the IS failure rate remains stubbornly high. A Panel session was held at the IFIP Working Group 8.6 conference in Bangalore in 2013 which forms the subject of this Special Issue. Its aim was to reflect on the need for new perspectives and research directions, to provide insights and further guidance for managers on factors enabling IS success and avoiding IS failure. Several key issues emerged, such as the need to study problems from multiple perspectives, to move beyond narrow considerations of the IT artifact, and to venture into underexplored organizational contexts, such as the public sector. © 2014 Springer Science+Business Media New York

Glyphosate resistance in four different populations of Lolium rigidum is associated with reduced translocation of glyphosate to meristematic zones

The definitive version is available at www.blackwell-synergy.comWeed populations with resistance to glyphosate have evolved over the last 7 years, since the discovery of the first glyphosate-resistant populations of Lolium rigidum in Australia. Four populations of L. rigidum from cropping, horticultural and viticultural areas in New South Wales and South Australia were tested for resistance to glyphosate by dose–response experiments. All populations required considerably more glyphosate to achieve 50% control compared with a known susceptible population, indicating they were resistant to glyphosate. Translocation of glyphosate within these resistant populations was examined by following the movement of radiolabelled glyphosate applied to a mature leaf. All resistant plants translocated significantly more herbicide to the tip of the treated leaf than did susceptible plants. Susceptible plants translocated twice as much herbicide to the stem meristematic portion of the plant compared with resistant plants. These different translocation patterns suggest an association between glyphosate resistance in L. rigidum and the ability of glyphosate to accumulate in the shoot meristem.A M Wakelin, D F Lorraine-Colwill, C Presto

Participação do nitrogênio na indução de injúrias foliares e na eficácia do herbicida glyphosate

Com o objetivo de avaliar diferentes aspectos da participação do nitrogênio na indução de injúrias foliares e na eficácia do herbicida glyphosate, foram desenvolvidos três experimentos, sendo dois em casa de vegetação, com as espécies Avena strigosa e Ipomoea triloba + Sorghum halepense, e um em campo, com Brachiaria decumbens. Avaliou-se a aplicação de glyphosate combinado com ureia (U), com sulfato de amônio (SA) e com U+AS, além de fertilização prévia do solo com nitrogênio e pulverização de caldas concentradas com até 20% de N. A pulverização de caldas concentradas com até 20% de N não dessecou adequadamente as espécies A. strigosa e B. decumbens, provocando danos máximos de cerca de 30%. A utilização de solução de SA ou de U+SA como veículo de pulverização do glyphosate elevou o controle de I. triloba. As soluções nitrogenadas aceleraram a atividade do glyphosate para dessecação de S. halepense, porém, sem diferenças visíveis aos 28 dias após aplicação. A escolha da dose adequada de glyphosate (1.800 g ha-1) para dessecação de B. decumbens foi fundamental para obtenção de elevado controle, sendo que a única alternativa que elevou a eficácia da menor dose do produto foi a fertilização prévia do solo com 150 kg ha-1 de SA