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The order Phyllachorales (Pezizomycotina, Ascomycota) is a group of biotrophic, obligate plant parasitic fungi with a tropical distribution and high host specificity. Traditionally two families are recognised within this order: Phyllachoraceae and Phaeochoraceae, based mostly on morphological and host characteristics. Currently, the position of the order within the class Sordariomycetes is inconclusive, as well as the monophyly of the order, and its internal phylogenetic structure. Here we present a phylogeny of the order Phyllachorales based on sequence data of 29 species with a broad host range resulting from a wide geographical sampling. We inferred Maximum Likelihood and Bayesian phylogenies from data of five DNA regions: nrLSU rDNA, nrSSU rDNA, ITS rDNA, and the protein coding genes RPB2, and TEF1. We found that the order Phyllachorales is monophyletic and related to members of the subclass Sordariomycetidae within Sordariomycetes. Within the order, members of the family Phaeochoraceae form a monophyletic group, and the family Phyllachoraceae is split into two lineages. Maximum Likelihood ancestral state reconstructions indicate that the ancestor of Phyllachorales had a monocotyledonous host plant, immersed perithecia, and a black stroma. Alternative states of these characters evolved multiple times independently within the order. Based on our results we redefine the family Phyllachoraceae and propose the new family Telimenaceae with Telimena erythrinae as type species, resulting in three families in the order. Species of Telimena spp. occur in several monocotyledonous and eudicotyledonous host plants except Poaceae, and generally have enlarged black pseudostroma around the perithecia, a character not present in species of Phyllachoraceae.

RESUMEN

La hiponatremia con natriuresis asociada a una enfermedad fue descrita inicialmente 1950 por Peters y colaboradores, quienes informaron de este problema en pacientes con enfermedad cerebral difusa, con incremento en las concentraciones del sodio urinario y un excesivo volumen urinario, ocasionando Hiponatremia y deshidratación. Las características fundamentales del síndrome cerebral perdedor de sal (SCPS) son: hiponatremia, hiposmolaridad plásmatica, osmolaridad urinaria mayor que la plasmática, natriuresis excesiva y delepción de volumen el diagnóstico diferencial debe hacerse claramente con el síndrome de secreción inapropiada de hormona antidiurética (SSIHAD) por lo diferente de sus tratamientos; en el SCPS debe corregirse la volemia y normalizar la natremia. El tratamiento incorrecto puede empeorar la condición de base con pobres resultados neurológicos

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RESUMEN

The cysteine desulfurase enzymes NifS and IscS provide sulfur for the biosynthesis of Fe/S proteins. NifU and IscU have been proposed to serve as template or scaffold proteins in the initial Fe/S cluster assembly events, but the mechanism of sulfur transfer from NifS or IscS to NifU or IscU has not been elucidated. We have employed [(35)S]cysteine radiotracer studies to monitor sulfur transfer between IscS and IscU from Escherichia coli and have used direct binding measurements to investigate interactions between the proteins. IscS catalyzed transfer of (35)S from [(35)S]cysteine to IscU in the absence of additional thiol reagents, suggesting that transfer can occur directly and without involvement of an intermediate carrier. Surface plasmon resonance studies and isothermal titration calorimetry measurements further revealed that IscU binds to IscS with high affinity (K(d) approximately 2 microm) in support of a direct transfer mechanism. Transfer was inhibited by treatment of IscU with iodoacetamide, and (35)S was released by reducing reagents, suggesting that transfer of persulfide sulfur occurs to cysteinyl groups of IscU. A deletion mutant of IscS lacking C-terminal residues 376-413 (IscSDelta376-413) displayed cysteine desulfurase activity similar to the full-length protein but exhibited lower binding affinity for IscU, decreased ability to transfer (35)S to IscU, and reduced activity in assays of Fe/S cluster assembly on IscU. The findings with IscSDelta376-413 provide additional support for a mechanism of sulfur transfer involving a direct interaction between IscS and IscU and suggest that the C-terminal region of IscS may be important for binding IscU.

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Several authors had reported high blood volumes (BV) and Low placental residual blood volumes (PRBV) in hypoxic human newborns, and also in asphyxiated experimentally animals. Those findings could be explained by and exaggerated intrauterine placental transfusion, ante or intrapartum. The authors had observed high cord blood and 24-48 hs. hematocrits in meconium-stained amniotic fluid (MSAF) and/or low 1 minute Apgar score newborns (Nb), despite early cord clamping. Sometimes, by delaying cord clamping up to 1 minute, those hematocrits had a tendency to decrease, instead of increasing. In view of that, it was decided to measure BV in a small group of similar type of Nb's with Evans blue (T-1824) and to practice in some of them a delayed cord clamping, but elevating the infant above the introitus (DECC). The BV values obtained were a little higher than the ones from the literature, being the most elevated in Nb's with MSAF and the lowest from cesarean. Also, the early cord clamping babies had higher BV than the DECC. All the MSAF Nb's had low plasmatic BV. BV was positively related to Birth Weight and the Hematocrit, and inversely to the Apgar score and the cord blood pH. Unexpectedly, delayed cord clamping was only slightly related to Red Cell BV, not to BV. MSAF constitutes 10% of all deliveries and delayed cord clamping has to be re-evaluated, because it offers a good chance for those babies of developing a normal BV or Hct's.

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