Polyphyly, gene-duplication and extensive allopolyploidy framed the evolution of the ephemeral Vulpia grasses and other fine-leaved Loliinae (Poaceae).

The fine-leaved Loliinae is one of the temperate grass lineages that is richest in number of evolutionary switches from perennial to annual life-cycle, and also shows one of the most complex reticulate patterns involving distinct diploid and allopolyploid lineages. Eight distinct annual lineages, that have traditionally been placed in the genus Vulpia and in other fine-leaved ephemeral genera, have apparently emerged from different perennial Festuca ancestors. The phenotypically similar Vulpia taxa have been reconstructed as polyphyletic, with polyploid lineages showing unclear relationships to their purported diploid relatives. Interspecific and intergeneric hybridization is, however, rampant across different lineages. An evolutionary analysis based on cloned nuclear low-copy GBSSI (Granule-Bound Starch Synthase I) and multicopy ITS (Internal Transcribed Spacer) sequences has been conducted on representatives of most Vulpia species and other fine-leaved lineages, using Bayesian consensus and agreement trees, networking split graphs and species tree-based approaches, to disentangle their phylogenetic relationships and to identify the parental genome donors of the allopolyploids. Both data sets were able to reconstruct a congruent phylogeny in which Vulpia was resolved as polyphyletic from at least three main ancestral diploid lineages. These, in turn, participated in the origin of the derived allopolyploid Vulpia lineages together with other Festuca-like, Psilurus-like and some unknown genome donors. Long-distance dispersal events were inferred to explain the polytopic origin of the Mediterranean and American Vulpia lineages.

Divergence and biogeography of the recently evolved Macaronesian red Festuca (Gramineae) species inferred from coalescence-based analyses.

Studying the biogeography and the phylogeography of the endemic Macaronesian red Festuca species (Loliinae, Poaceae) is of prime interest in understanding the speciation and colonization patterns of recently evolved groups in oceanic archipelagos. Coalescence-based analyses of plastid trnLF sequences were employed to estimate evolutionary parameters and to test different species-history scenarios that model the pattern of species divergence. Bayesian IM estimates of species divergence times suggested that ancestral lineages of diploid Macaronesian and Iberian red fescues could have diverged between 1.2 and 1.57 Ma. When empirical data were compared to coalescence-based simulated distributions of discordance and p-distance statistics, two species-history models were chosen in which the first branching lineage derived in Canarian Festuca agustinii. Its sister lineage could have involved a recent polytomy leading to the Madeiran Festuca jubata, the Azorean Festuca francoi + Festuca petraea and the continental Festuca rivularis lineages (Canarian model) or the sequential branching of lineages leading to F. jubata and finally to the sister clades of F. rivularis and F. francoi + F. petraea (Sequential model). Nested clade phylogeographic analysis (NCPA) and a first adapted host-parasite co-evolutionary ParaFit method were used to detect the phylogeographic signal. NCPA inferred long-distance colonizations for the entire diploid red Festuca complex, but allopatric-fragmentation and isolation-by-distance (IBD) patterns were inferred within archipelagos. In addition, the ParaFit method suggested a generalized pattern of a stepping-stone model at all hierarchical levels. Maximum-likelihood-based dispersal-extinction-cladogenesis (DEC) models were superimposed on the Sequential model species tree. The three-independent-colonization (3IC) model was the best supported biogeographic scenario, concurring with previous analysis based on multilocus AFLP data.

Substrate specificity of the 3-methylcrotonyl coenzyme A (CoA) and geranyl-CoA carboxylases from Pseudomonas aeruginosa.

Biotin-containing 3-methylcrotonyl coenzyme A (MC-CoA) carboxylase (MCCase) and geranyl-CoA (G-CoA) carboxylase (GCCase) from Pseudomonas aeruginosa were expressed as His-tagged recombinant proteins in Escherichia coli. Both native and recombinant MCCase and GCCase showed pH and temperature optima of 8.5 and 37 degrees C. The apparent K(0.5) (affinity constant for non-Michaelis-Menten kinetics behavior) values of MCCase for MC-CoA, ATP, and bicarbonate were 9.8 microM, 13 microM, and 0.8 microM, respectively. MCCase activity showed sigmoidal kinetics for all the substrates and did not carboxylate G-CoA. In contrast, GCCase catalyzed the carboxylation of both G-CoA and MC-CoA. GCCase also showed sigmoidal kinetic behavior for G-CoA and bicarbonate but showed Michaelis-Menten kinetics for MC-CoA and the cosubstrate ATP. The apparent K(0.5) values of GCCase were 8.8 microM and 1.2 microM for G-CoA and bicarbonate, respectively, and the apparent K(m) values of GCCase were 10 microM for ATP and 14 microM for MC-CoA. The catalytic efficiencies of GCCase for G-CoA and MC-CoA were 56 and 22, respectively, indicating that G-CoA is preferred over MC-CoA as a substrate. The enzymatic properties of GCCase suggest that it may substitute for MCCase in leucine catabolism and that both the MCCase and GCCase enzymes play important roles in the leucine and acyclic terpene catabolic pathways.

The atu and liu clusters are involved in the catabolic pathways for acyclic monoterpenes and leucine in Pseudomonas aeruginosa.

Evidence suggests that the Pseudomonas aeruginosa PAO1 gnyRDBHAL cluster, which is involved in acyclic isoprenoid degradation (A. L. Díaz-Pérez, N. A. Zavala-Hernández, C. Cervantes, and J. Campos-García, Appl. Environ. Microbiol. 70:5102-5110, 2004), corresponds to the liuRABCDE cluster (B. Hoschle, V. Gnau, and D. Jendrossek, Microbiology 151:3649-3656, 2005). A liu (leucine and isovalerate utilization) homolog cluster was found in the PAO1 genome and is related to the catabolism of acyclic monoterpenes of the citronellol family (AMTC); it was named the atu cluster (acyclic terpene utilization), consisting of the atuCDEF genes and lacking the hydroxymethyl-glutaryl-coenzyme A (CoA) lyase (HMG-CoA lyase) homolog. Mutagenesis of the atu and liu clusters showed that both are involved in AMTC and leucine catabolism by encoding the enzymes related to the geranyl-CoA and the 3-methylcrotonyl-CoA pathways, respectively. Intermediary metabolites of the acyclic monoterpene pathway, citronellic and geranic acids, were accumulated, and leucine degradation rates were affected in both atuF and liuD mutants. The alpha subunit of geranyl-CoA carboxylase and the alpha subunit of 3-methylcrotonyl-CoA carboxylase (alpha-MCCase), encoded by the atuF and liuD genes, respectively, were both induced by citronellol, whereas only the alpha-MCCase subunit was induced by leucine. Both citronellol and leucine also induced a LacZ transcriptional fusion at the liuB gene. The liuE gene encodes a probable hydroxy-acyl-CoA lyase (probably HMG-CoA lyase), an enzyme with bifunctional activity that is essential for both AMTC and leucine degradation. P. aeruginosa PAO1 products encoded by the liuABCD cluster showed a higher sequence similarity (77.2 to 79.5%) with the probable products of liu clusters from several Pseudomonas species than with the atuCDEF cluster from PAO1 (41.5%). Phylogenetic studies suggest that the atu cluster from P. aeruginosa could be the result of horizontal transfer from Alphaproteobacteria. Our results suggest that the atu and liu clusters are bifunctional operons involved in both the AMTC and leucine catabolic pathways.

Síndrome de Cushing debido a hiperplasia suprarrenal macronodular independiente de ACTH tratado mediante adrenalectomía unilateral: dos casos / Cushing’s syndrome due to ACTH-independent macronodular adrenal hyperplasia treated through unilateral adrenalectomy: report of two cases

La hiperplasia adrenal bilateral macronodular como causa de síndrome de Cushing es una entidad debatida en cuanto a su etiología (hipofisaria frente a adrenal) e incluso en cuanto a su tratamiento idóneo. Cada vez más se opta por medidas terapéuticas menos agresivas como la suprarrenalectomía unilateral. A continuación, se presentan 2 casos cuyo proceso diagnóstico nos ha servido para reabrir el debate del origen de la enfermedad, dada la presencia de nódulos hipofisarios en ambos casos y una determinación inicialmente elevada de corticotropina en el segundo. En cuanto al tratamiento, se ha practicado suprarrenalectomía unilateral de la glándula dominante (valoración realizada mediante imágenes de tomografía y gammagrafía) en ambos casos, con resultado satisfactorio en la evolución a medio plazo (AU)

The causes and treatment of ACTH-independent macronodular adrenal hyperplasia as a cause of Cushing's syndrome remain unclear. A pituitary adenoma could be responsible for the adrenal hyperplasia, but the adrenal gland could be the primary problem in many cases. Less aggressive treatments such as unilateral laparoscopic adrenalectomy are increasingly used. We present two cases of ACTH-independent macronodular adrenal hyperplasia. These cases led us to reopen the debate about the etiology of the disease, given the presence of pituitary nodules in both patients and initially elevated ACTH values in the second patient. In both patients, unilateral adrenalectomy of the dominant gland (evaluated through computed tomography and scintigraphy) was performed with satisfactory outcomes in the medium term (AU)

The gnyRDBHAL cluster is involved in acyclic isoprenoid degradation in Pseudomonas aeruginosa.

Pseudomonas aeruginosa PAO1 mutants affected in the ability to degrade acyclic isoprenoids were isolated with transposon mutagenesis. The gny cluster (for geranoyl), which encodes the enzymes involved in the lower pathway of acyclic isoprenoid degradation, was identified. The gny cluster is constituted by five probable structural genes, gnyDBHAL, and a possible regulatory gene, gnyR. Mutations in the gnyD, gnyB, gnyA, or gnyL gene caused inability to assimilate acyclic isoprenoids of the citronellol family of compounds. Transcriptional analysis showed that expression of the gnyB gene was induced by citronellol and repressed by glucose, whereas expression of the gnyR gene had the opposite behavior. Western blot analysis of citronellol-grown cultures showed induction of biotinylated proteins of 70 and 73 kDa, which probably correspond to 3-methylcrotonoyl-coenzyme A (CoA) carboxylase and geranoyl-CoA carboxylase (GCCase) alpha subunits, respectively. The 73-kDa biotinylated protein, identified as the alpha-GCCase subunit, is encoded by gnyA. Intermediary metabolites of the isoprenoid pathway, citronellic and geranic acids, were shown to accumulate in gnyB and gnyA mutants. Our data suggest that the protein products encoded in the gny cluster are the beta and alpha subunits of geranoyl-CoA carboxylase (GnyB and GnyA), the citronelloyl-CoA dehydrogenase (GnyD), the gamma-carboxygeranoyl-CoA hydratase (GnyH), and the 3-hydroxy-gamma-carboxygeranoyl-CoA lyase (GnyL). We conclude that the gnyRDBHAL cluster is involved in isoprenoid catabolism.

Fracturas de la extremidad distal del radio en el anciano / Distal radius fractures in elderly

Se realiza un estudio epidemiológico retrospectivo en 114 pacientes mayores de 65 años de edad que presentaban una fractura de la extremidad distal del radio (fractura de Colles). Se encontró una tasa de incidencia acumulada del 0,23 por ciento, mayor predominio del sexo femenino (87 por ciento de los casos), mayor procedencia del medio urbano (59 por ciento) y mayor presentación estacional en los meses de agosto y octubre. El tipo de fractura más frecuente fue el tipo II de Sarmiento (47 por ciento de los casos), con discreto predominio del lado derecho (56 por ciento). Este tipo de fractura se asoció a otras lesiones en el 15 por ciento de los casos, y en cuanto a la causa de producción un 85 por ciento se debió a un traumatismo moderado o leve (AU)

Hipoglucemia facticia: a propósito de un caso / Factitious hypoglycemia: case report

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[Attempted suicide: epidemiological changes between 1969-1996. A retrospective study of 1,150 cases]. / Intento de suicidio: cambios epidemiológicos entre 1969-1996. Estudio retrospectivo de 1.150 casos.

BACKGROUND: Over the last 40 years, suicide attempts have become a health problem of epidemic proportions. In order to update preventive measures, we describe the variations observed in the epidemiologic pattern of patients who attempted suicide between 1969-96. METHOD: A total of 1,150 suicide attempts seen in the Emergency Service of a General Hospital during this period was analyzed. The study protocol included: sociodemographic data, psychiatric antecedents and diagnosis, suicide behaviour and triggering life-events. RESULTS: Throughout the 27 years of the study the most relevant changes in the suicide-attempt population were: progressive levelling between males and females and an increase in antecedents and previous psychiatric treatments (11% vs 74%). The distribution of the psychiatric diagnoses changed in its relative frequency. A dramatic increase was observed in the number of patients who repeated the suicide attempt (22% vs 50%). Triggering life-events tended to vary in relation to sociological changes. CONCLUSIONS: Throughout the study period we observed a progressive increase of psychiatric diagnoses in suicidal patients. Therapeutic programs are needed to prevent repetition of suicide attempts, both during periods of psychopathologic exacerbation and during psychosocial adaptation crises triggered by life-events.

PGE2 causes a coordinate decrease in the steady state levels of fibronectin and types I and III procollagen mRNAs in normal human dermal fibroblasts.

Prostaglandin E2 (PGE2) caused inhibition of collagen and fibronectin synthesis by confluent cultures of human dermal fibroblasts. Dot-blot hybridization to cDNA probes complementary to Types I and III procollagens and fibronectin demonstrated that inhibition of protein production was accompanied by a coordinate decrease in the steady-state levels of the corresponding mRNAs. Blockade of transcription by actinomycin D demonstrated that PGE2 did not alter the stability of these mRNA. These results indicate that PGE2 is capable of exerting modulation of extracellular matrix biosynthesis, and that these effects occur at a transcriptional level.