Analysis of Lsm Protein-Mediated Regulation in the Haloarchaeon Haloferax mediterranei.

The Sm protein superfamily includes Sm, like-Sm (Lsm), and Hfq found in the Eukarya, Archaea, and Bacteria domains. Archaeal Lsm proteins have been shown to bind sRNAs and are probably involved in various cellular processes, suggesting a similar function in regulating sRNAs by Hfq in bacteria. Moreover, archaeal Lsm proteins probably represent the ancestral Lsm domain from which eukaryotic Sm proteins have evolved. In this work, Haloferax mediterranei was used as a model organism because it has been widely used to investigate the nitrogen cycle and its regulation in Haloarchaea. Predicting this protein's secondary and tertiary structures has resulted in a three-dimensional model like the solved Lsm protein structure of Archaeoglobus fulgidus. To obtain information on the oligomerization state of the protein, homologous overexpression and purification by means of molecular exclusion chromatography have been performed. The results show that this protein can form hexameric complexes, which can aggregate into 6 or 12 hexameric rings depending on the NaCl concentration and without RNA. In addition, the study of transcriptional expression via microarrays has allowed us to obtain the target genes regulated by the Lsm protein under nutritional stress conditions: nitrogen or carbon starvation. Microarray analysis has shown the first universal stress proteins (USP) in this microorganism that mediate survival in situations of nitrogen deficiency.

A symbolic Neanderthal accumulation of large herbivore crania.

This work examines the possible behaviour of Neanderthal groups at the Cueva Des-Cubierta (central Spain) via the analysis of the latter's archaeological assemblage. Alongside evidence of Mousterian lithic industry, Level 3 of the cave infill was found to contain an assemblage of mammalian bone remains dominated by the crania of large ungulates, some associated with small hearths. The scarcity of post-cranial elements, teeth, mandibles and maxillae, along with evidence of anthropogenic modification of the crania (cut and percussion marks), indicates that the carcasses of the corresponding animals were initially processed outside the cave, and the crania were later brought inside. A second round of processing then took place, possibly related to the removal of the brain. The continued presence of crania throughout Level 3 indicates that this behaviour was recurrent during this level's formation. This behaviour seems to have no subsistence-related purpose but to be more symbolic in its intent.

Towards the Elucidation of Assimilative nasABC Operon Transcriptional Regulation in Haloferax mediterranei.

The assimilatory pathway of the nitrogen cycle in the haloarchaeon Haloferax mediterranei has been well described and characterized in previous studies. However, the regulatory mechanisms involved in the gene expression of this pathway remain unknown in haloarchaea. This work focuses on elucidating the regulation at the transcriptional level of the assimilative nasABC operon (HFX_2002 to HFX_2004) through different approaches. Characterization of its promoter region using ß-galactosidase as a reporter gene and site-directed mutagenesis has allowed us to identify possible candidate binding regions for a transcriptional factor. The identification of a potential transcriptional regulator related to nitrogen metabolism has become a real challenge due to the lack of information on haloarchaea. The investigation of protein-DNA binding by streptavidin bead pull-down analysis combined with mass spectrometry resulted in the in vitro identification of a transcriptional regulator belonging to the Lrp/AsnC family, which binds to the nasABC operon promoter (p.nasABC). To our knowledge, this study is the first report to suggest the AsnC transcriptional regulator as a powerful candidate to play a regulatory role in nasABC gene expression in Hfx. mediterranei and, in general, in the assimilatory nitrogen pathway.

ADCK2 Haploinsufficiency Reduces Mitochondrial Lipid Oxidation and Causes Myopathy Associated with CoQ Deficiency.

Fatty acids and glucose are the main bioenergetic substrates in mammals. Impairment of mitochondrial fatty acid oxidation causes mitochondrial myopathy leading to decreased physical performance. Here, we report that haploinsufficiency of ADCK2, a member of the aarF domain-containing mitochondrial protein kinase family, in human is associated with liver dysfunction and severe mitochondrial myopathy with lipid droplets in skeletal muscle. In order to better understand the etiology of this rare disorder, we generated a heterozygous Adck2 knockout mouse model to perform in vivo and cellular studies using integrated analysis of physiological and omics data (transcriptomics-metabolomics). The data showed that Adck2+/- mice exhibited impaired fatty acid oxidation, liver dysfunction, and mitochondrial myopathy in skeletal muscle resulting in lower physical performance. Significant decrease in Coenzyme Q (CoQ) biosynthesis was observed and supplementation with CoQ partially rescued the phenotype both in the human subject and mouse model. These results indicate that ADCK2 is involved in organismal fatty acid metabolism and in CoQ biosynthesis in skeletal muscle. We propose that patients with isolated myopathies and myopathies involving lipid accumulation be tested for possible ADCK2 defect as they are likely to be responsive to CoQ supplementation.

Caracterización epidemiológica de una población de pacientes del programa ®manejo integral de la enfermedad pulmonar obstructiva crónica¼ de la EPS Sanitas en Bogotá / Patient characteristics and diagnostic evaluation in a management programme of Chronic Obstructive Pulmonary Disease (COPD) in Bogota (2640m), Colombia

Objetivo: describir las características epidemiológicas de los pacientes al ingreso a un programa de manejo integral de la EPOC en Bogotá. Material y método: estudio de corte transversal. Evaluamos 756 pacientes con diagnóstico presuntivo de EPOC. Se confirmaron 408 por espirometría (54 por ciento), de los cuales se excluyeron 57. Se describen las características demográficas, clínicas, paraclínicas de 351 pacientes y su asociación con el grado de severidad de la obstrucción. Análisis estadístico: Se presentan las frecuencias y medidas de tendencia central y dispersión. Se utilizó el coeficiente paramétrico de Pearson o el coeficiente no-paramétrico de Spearman según normalidad, a un nivel de significancia del 1 por ciento (p<0.01). Resultados: La EPOC, definida por una relación VEF1/CVF < 70 por ciento, post-broncodilatador, se confirmó en el 54 por ciento de los pacientes. La edad promedio fue 72,8±9 años, 61 por ciento hombres, fumadores activos 9,1 por ciento, expuestos a humo de leña 33,3 por ciento. El 68,6 por ciento no utiliza correctamente los inhaladores. El VEF1 promedio fue 1.285±517 litros. El 68,1 por ciento y 46,4 por ciento no se habían vacunado contra neumococo e influenza respectivamente. Se encontró correlación directa y significativa entre VEF1 (por ciento) con saturación, PaO2 e índice de masa corporal; e inversa con PCO2, hematocrito e índice de disnea; no se encontró correlación con la escala de calidad de vida (S. George) y test de marcha en 6 minutos. Conclusiones: El 54 por ciento de los pacientes remitidos están adecuadamente diagnosticados. Hay baja cobertura en vacunación contra neumococo e influenza, la mayoría utilizan en forma incorrecta los inhaladores. Resaltamos la importancia de utilizar la espirometría como herramienta básica en el diagnóstico de EPOC, al igual que programas educativos que impacten en el manejo de la EPOC. (Nota el enlace a Internet opera para todo el fasciculo 1/2008).

Activation of Mst1 causes dilated cardiomyopathy by stimulating apoptosis without compensatory ventricular myocyte hypertrophy.

Activation of mammalian sterile 20-like kinase 1 (Mst1) by genotoxic compounds is known to stimulate apoptosis in some cell types. The importance of Mst1 in cell death caused by clinically relevant pathologic stimuli is unknown, however. In this study, we show that Mst1 is a prominent myelin basic protein kinase activated by proapoptotic stimuli in cardiac myocytes and that Mst1 causes cardiac myocyte apoptosis in vitro in a kinase activity-dependent manner. In vivo, cardiac-specific overexpression of Mst1 in transgenic mice results in activation of caspases, increased apoptosis, and dilated cardiomyopathy. Surprisingly, however, Mst1 prevents compensatory cardiac myocyte elongation or hypertrophy despite increased wall stress, thereby obscuring the use of the Frank-Starling mechanism, a fundamental mechanism by which the heart maintains cardiac output in response to increased mechanical load at the single myocyte level. Furthermore, Mst1 is activated by ischemia/reperfusion in the mouse heart in vivo. Suppression of endogenous Mst1 by cardiac-specific overexpression of dominant-negative Mst1 in transgenic mice prevents myocyte death by pathologic insults. These results show that Mst1 works as both an essential initiator of apoptosis and an inhibitor of hypertrophy in cardiac myocytes, resulting in a previously unrecognized form of cardiomyopathy.

Histoplasmose tegumentar: relato de um caso / Muco-cutaneus histoplasmosis: a case report

Apresentaçäo de caso de histoplasmose cutaneomucosa num indivíduo masculino de 61 anos procedentes de Santa Bárbara do Oeste, SP. O paciente tinha antecendentes de leishmaniose tegumentar e tuberculose pulmonar e apresentava insuficiência renal. O exame direto para fungos, cultura e inoculaçäo e exame anatomopatológico confirmou a presença do Histoplasma capsulatum nas lesöes. O tratamento de escolha foi o ketoconazol 400mg/dia via oral por dois meses, por ser o paciente portador de insuficiência renal. O resultado do tratamento foi satisfatório com regressäo das lesöes e ausência de efeitos colaterais da droga