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De novo gene disruptions in children on the autistic spectrum   总被引:2,自引:0,他引:2  
Exome sequencing of 343 families, each with a single child on the autism spectrum and at least one unaffected sibling, reveal de novo small indels and point substitutions, which come mostly from the paternal line in an age-dependent manner. We do not see significantly greater numbers of de novo missense mutations in affected versus unaffected children, but gene-disrupting mutations (nonsense, splice site, and frame shifts) are twice as frequent, 59 to 28. Based on this differential and the number of recurrent and total targets of gene disruption found in our and similar studies, we estimate between 350 and 400 autism susceptibility genes. Many of the disrupted genes in these studies are associated with the?fragile X protein, FMRP, reinforcing links between autism and synaptic plasticity. We find FMRP-associated genes are under greater purifying selection than the remainder of genes and suggest they are especially dosage-sensitive targets of cognitive disorders.  相似文献   
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The medicine called Tamsulosin was produced 25 years ago and since then almost 10 new synthesis route has been known. Each process shows the researchers' workstyle, every year, which mainly differs in the way of separating the enantiomers. The applied reaction steps also reflect the development over the past 25 years and the new synthesis is influenced by the antecedents. The key-intermediate used in our new method is a racemic secondary amine derivative, which is unknown in the literature before and for resolving it, we worked out a quite advantegeous process. By using an optically active secondary amine, side reactions can be avoided.  相似文献   
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The authors analyze the progress achieved in the treatment of low-grade as well as of high-grade non-Hodgkin's lymphomas. The challenging task in the treatment of low-grade or indolent lymphomas still is to decide whether watchful waiting is sufficient or whether chemotherapy is necessary and how aggressive this treatment should be. Among the new chemotherapeutic agents the role of purine analogues should be emphasized, fludarabin is especially important in the treatment of chronic lymphocytic leukemia and follicular lymphoma, while pentostatin and cladribine have revolutionized the treatment of hairy cell leukemia. Treatment with monoclonal antibodies, radioimmunoconjugates as well as autologous or allogeneic stem cell transplantation are potential new therapeutic options in the treatment of low-grade non-Hodgkin's lymphomas. In the case of aggressive non-Hodgkin's lymphomas risk-adapted strategies help the choice between standard or more intensive treatment options. In patients with relapsed high-grade lymphomas stem cell transplantation is indicated. In patients with marginal zone lymphoma the combination of hyperCVAD protocol + stem cell transplantation greatly improves prognosis.  相似文献   
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Although activation of protein kinase C (PKC) is known to promote cell survival and protect against cell death, the PKC targets and pathways that serve this function have remained elusive. Here we demonstrate that two potent activators of PKC, 12-O-tetradecanoylphorbol-13-acetate and bryostatin, both stimulate phosphorylation of Bad at Ser(112), a site known to regulate apoptotic cell death by interleukin-3. PKC inhibitors but not PI 3-kinase/Akt inhibitors block 12-O-tetradecanoylphorbol-13-acetate-stimulated Bad phosphorylation. PKC isoforms tested in vitro were unable to phosphorylate Bad at Ser(112), suggesting that PKC acts indirectly to activate a downstream Bad kinase. p90(RSK) and family members RSK-2 and RSK-3 are activated by phorbol ester and phosphorylate Bad at Ser(112) both in vitro and in vivo. p90(RSK) stimulates binding of Bad to 14-3-3 and blocks Bad-mediated cell death in a Ser(112)-dependent manner. These findings suggest that p90(RSK) can function in a PKC-dependent pathway to promote cell survival via phosphorylation and inactivation of Bad-mediated cell death.  相似文献   
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The nature of the DNA damage-induced checkpoint signal that causes the arrest of cells prior to mitosis is unknown. To determine if this signal is transmitted through the cytoplasm or is confined to the nucleus, we created binucleate heterokaryon yeast cells in which one nucleus suffered an unrepairable double-strand break, and the second nucleus was undamaged. In most of these binucleate cells, the damaged nucleus arrested prior to spindle elongation, while the undamaged nucleus completed mitosis, even when the strength of the damage signal was increased. The arrest of the damaged nucleus was dependent upon the function of the RAD9 checkpoint gene. Thus, the DNA damage checkpoint causing G2/M arrest is regulated by a signal that is nuclear limited.  相似文献   
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