651 research outputs found
A new species of Ribautiella (Myriapoda, Symphyla, Scolopendrellidae) from an Amazonian black-water inundation forest and notes on its natural history and ecology
Ribautiella amazonica is described from a black-water inundation forest near Manaus, Brazil. The genus is recorded for the first time for the Americas. R. amazonica was predominantly collected from the forest soil, mainly between 7 and 14 cm depth and is considered euedaphic. Data indicate, that advanced immature stages and adults withstand forest-inundation of 5 - 6 months duration in the soil and reproduce in the early part of the emersion period
A study of Neotropical Symphyla (Myriapoda): list of species, keys to genera and description of two new Amazonian species
A provisional list of the Neotropical species of Symphyla and keys to Neotropical genera are given. Two new species from central Amazonia are described: Scolopendrellopsis tropicus and Symphylella adisi. Hanseniella orientalis is reported from South America for the first time
Pauropoda of a secondary forest near the Tarumã Mirím River, Amazonas, Brazil (Myriapoda, Pauropoda, Pauropodidae)
A large collection of Pauropoda from a secondary upland forest north of Manaus, Brazil, was investigated. A list of 26 species belonging to the family Pauropodidae was compiled: 15 new species of Allopauropus and two each of Scleropauropus, Hemipauropus, Polypauropus and Polypauropoides
Two new pauropod species from Central Amazonia (Myriapoda: Pauropoda: Pauropodidae)
Two new species ol Pauropoda frorn Lago Janauarí, near Manaus. Allopauropus janauariensis n.sp. and Scleropauropus angularis n.sp. are here described
The taxonomic composition and affinities of the Brazilian Pauropoda with description of three new species from Central Amazonia (Myriapoda, Pauropoda: Pauropodidae)
The taxonomic composition and affinities of the Brazilian Pauropoda are discussed. Three new species of Pauropoda are described from Central Amazonia: Allopauropus hylekoites, from a blackwater inundation forest near the Rio Tarumã Mirím, Stylopauropoides dytanekes and Polypauropus duckensis from a primary forest in Reserva Florestal A. Ducke
Pauropoda from upland and inundation forests in Central Amazonia, Brazil (Myriapoda, Pauropoda: Millotauropodidae, Pauropodidae)
A large collection of Pauropoda from upland and inundation forests in Central Amazonia has been studied from taxonomical point of view. Fifty-two species were found in 7 genera, one in Millotauropodidae and 6 in Pauropodidae. Two new subgenera are described. Perissopauropus in Allopauropus and Nesopauropus in Cauvetauropns. Twenty-five new species are described: Millotauropus acostae, Allopauropus ieenus, A. tohoius, A. junki, A. anomaios, A. mirimus, A. korynetes, A. pachyflagellus, A. aius, A. hylaios, A. campinaranicus, A. careiroensis, A. kordylinos, A. disappendicalis, A. dischides, A. aduncus, A. amphikomos; Cauvetauropus biglobulosus; Scleropauropus rimatus, S. heritae; Polypauropus tchimbus; Polypauropoides naous, P. foliolus, P. monosetosus and P. cuneatus
Cross talk between Wnt/β-catenin and Irf8 in leukemia progression and drug resistance
Progression and disease relapse of chronic myeloid leukemia (CML) depends on leukemia-initiating cells (LIC) that resist treatment. Using mouse genetics and a BCR-ABL model of CML, we observed cross talk between Wnt/{beta}-catenin signaling and the interferon-regulatory factor 8 (Irf8). In normal hematopoiesis, activation of {beta}-catenin results in up-regulation of Irf8, which in turn limits oncogenic {beta}-catenin functions. Self-renewal and myeloproliferation become dependent on {beta}-catenin in Irf8-deficient animals that develop a CML-like disease. Combined Irf8 deletion and constitutive {beta}-catenin activation result in progression of CML into fatal blast crisis, elevated leukemic potential of BCR-ABL-induced LICs, and Imatinib resistance. Interestingly, activated {beta}-catenin enhances a preexisting Irf8-deficient gene signature, identifying {beta}-catenin as an amplifier of progression-specific gene regulation in the shift of CML to blast crisis. Collectively, our data uncover Irf8 as a roadblock for {beta}-catenin-driven leukemia and imply both factors as targets in combinatorial therapy
Myriapoda at "Reserva Ducke", Central Amazonia/Brazil
Myriapoda contains the four recent classes Chilopoda, Diplopoda, Pauropoda and Symphyla. In total, 159 families, 2166 genera and >15162 species are known world-wide. Twenty-nine families, >93 genera and >401 described species occur in Amazonia. One-fifth of the families presently known in the myriapods are represented in Amazonia. About 3% of all described species live, and at least 9% of the species estimated to exist world-wide in Myriapoda are assumed to live in Amazonia. From the forest reserve 'Reserva Ducke' near Manaus, 22 families, 38 genera and 73 described species are known at present. The Chilopoda represent 5 families, 9 genera, 23 species and one undescribed morphospecies, the Diplopoda 13 families, 18 described genera, 14 species and 19 undescribed morphospecies, the Pauropoda 2 families, 7 genera, 31 species, and the Sympyla 2 families, 4 genera and 5 species. All names are liste
Deregulation of the endogenous C/EBPβ LIP isoform predisposes to tumorigenesis
Two long and one truncated isoforms (termed LAP*, LAP, and LIP, respectively) of the transcription factor CCAAT enhancer binding protein beta (C/EBPbeta) are expressed from a single intronless Cebpb gene by alternative translation initiation. Isoform expression is sensitive to mammalian target of rapamycin (mTOR)-mediated activation of the translation initiation machinery and relayed through an upstream open reading frame (uORF) on the C/EBPbeta mRNA. The truncated C/EBPbeta LIP, initiated by high mTOR activity, has been implied in neoplasia, but it was never shown whether endogenous C/EBPbeta LIP may function as an oncogene. In this study, we examined spontaneous tumor formation in C/EBPbeta knockin mice that constitutively express only the C/EBPbeta LIP isoform from its own locus. Our data show that deregulated C/EBPbeta LIP predisposes to oncogenesis in many tissues. Gene expression profiling suggests that C/EBPbeta LIP supports a pro-tumorigenic microenvironment, resistance to apoptosis, and alteration of cytokine/chemokine expression. The results imply that enhanced translation reinitiation of C/EBPbeta LIP promotes tumorigenesis. Accordingly, pharmacological restriction of mTOR function might be a therapeutic option in tumorigenesis that involves enhanced expression of the truncated C/EBPbeta LIP isoform. KEY MESSAGE: Elevated C/EBPbeta LIP promotes cancer in mice. C/EBPbeta LIP is upregulated in B-NHL. Deregulated C/EBPbeta LIP alters apoptosis and cytokine/chemokine networks. Deregulated C/EBPbeta LIP may support a pro-tumorigenic microenvironment
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