Septic shock secondary to an acute necrotizing community-acquired pneumonia with bacteremia due to Pseudomonas aeruginosa.

Pseudomonas aeruginosa is an uncommon cause of necrotizing acute community-acquired pneumonia (CAP). Only thirteen cases have been previously reported in the literature. In this article, we describe a case of previously healthy 80-year-old male patient, who presented in septic shock caused by necrotizing CAP. Despite inadequate empiric antimicrobial treatment, the patient survived and was able to return to his home after three weeks of hospitalization. To the best of our knowledge, this is the second case of septic shock secondary to P. aeruginosa necrotizing CAP and bacteremia, with optimal clinical outcome. We highlight the evolution of this pathology remains unpredictable, despite the factors related to the host and the bacterium.

Validación de la prueba nacional de pesquisa de trastornos de desarrollo psicomotor en niños menores de 6 años / Validation for screening test of detecting psychomotor development problems in children under six

Introducción. El uso de una prueba de pesquisa en los primeros años de vida permite la detección temprana de retrasos en el desarrollo psicomotor y su tratamiento oportuno. En la Argentina contamos con una Prueba Nacional de Pesquisa preparada en base a un estudio nacional. El objetivo del trabajo fue validar la prueba, comparando sus resultados con evaluaciones diagnósticas, realizadas en forma simultánea por varios servicios del Hospital Garrahan. Pacientes y métodos. Se seleccionó una muestra de 106 niños de 0 a 5,99 años que concurrían al área de bajo riesgo del Hospital. Se realizaron los siguientes estudios diagnósticos: evaluación del desarrollo psicomotor (Bayley II), examen neurológico, salud mental, coeficiente intelectual (Wechsler, Terman), conducta adaptativa (Vineland), lenguaje (prueba de Gardner receptiva y expresiva, ITPA), audición (emisiones otoacústicas, audiometría tonal, PEAT), examen visual. Se utilizó el DSM-IV como referencia de trastornos del desarrollo. Se evaluó la sensibilidad y especificidad obtenidas según la aplicación de diferentes puntos de corte (número de ítems fracasados). Resultados. El mejor punto de corte se estableció en un ítem tipo A o 2 tipo B, con una sensibilidad del 80%, especificidad: 93%, valor predictivo positivo: 94%, valor predictivo negativo: 77%, porcentaje de coincidencia: 85%. Fue inesperada la elevada prevalencia de problemas de desarrollo encontrada en la muestra: 57%. La prueba es capaz de detectar problemas en las cuatro áreas del desarrollo, incluidos trastornos del lenguaje. Conclusión. Los resultados confirman a la Prueba Nacional de Pesquisa como un instrumento válido para ser usado en el primer nivel de atención para el reconocimiento de niños con sospecha de sufrir trastornos del desarrollo. Asimismo, el trabajo de información permite establecer diferentes puntos de corte y constituye un instrumento útil para su aplicación en la práctica pediátrica.

The use of a screening test in the first years of life allows the early detection of delays of psychomotor development and its treatment, thus contributing to improve the prognosis of the child with special needs. In Argentina, a screening test for detecting developmental problems in children under 6, made with local children and data is available (PRUNAPE). A validation procedure for this test was carried out on 106 children attending at low risk outpatient clinic in Hospital Garrahan. The test was administered to the children together with a battery of diagnostic examinations and studies, performed by experienced specialists from different Hospital services: psychomotor development, neurology examination, mental health, intellectual quotient (Wechsler, Terman), adaptive behaviour (Vineland), language (Gardner expressive and receptive, ITPA), hearing (otoacustic emissions, audiometry, BERA), vision. The DSM ­IV was used as a reference for developmental problems. Using as a failure criterion to the PRUNAPE, the failure of performing correctly one type A item or two type B item, sensitivity of the test was 80%, specificity, 93%; positive predictive value, 95%; negative predictive value, 77%; overall agreement, 85%. A very high prevalence of developmental problems was found: 57%. PRUNAPE was found to be capable of detecting a wide range of problems. These results confirm PRUNAPE as a valuable instrument for early detection of developmental problems in paediatric practice at the primary care level.

Delayed and incomplete reprogramming of chromosome methylation patterns in bovine cloned embryos.

Full-term development has now been achieved in several mammalian species by transfer of somatic nuclei into enucleated oocytes [1, 2]. Although a high proportion of such reconstructed embryos can evolve until the blastocyst stage, only a few percent develop into live offspring, which often exhibit developmental abnormalities [3, 4]. Regulatory epigenetic markers such as DNA methylation are imposed on embryonic cells as normal development proceeds, creating differentiated cell states. Cloned embryos require the erasure of their somatic epigenetic markers so as to regain a totipotent state [5]. Here we report on differences in the dynamics of chromosome methylation between cloned and normal bovine embryos before implantation. We show that cloned embryos fail to reproduce distinguishable parental-chromosome methylation patterns after fusion and maintain their somatic pattern during subsequent stages, mainly by a highly reduced efficiency of the passive demethylation process. Surprisingly, chromosomes appear constantly undermethylated on euchromatin in morulae and blastocysts, while centromeric heterochromatin remains more methylated than that of normal embryos. We propose that the abnormal time-dependent methylation events spanning the preimplantation development of clones may significantly interfere with the epigenetic reprogramming, contributing to the high incidence of physiological anomalies occurring later during pregnancy or after clone birth.

A WASp-VASP complex regulates actin polymerization at the plasma membrane.

Proteins of the Wiskott-Aldrich syndrome and Ena/VASP families both play essential functions in the regulation of actin dynamics at the cell leading edge. However, possibilities of functional interplay between members of these two families have not been addressed. Here we show that, in hemopoietic cells, recruitment of the C-terminal VCA (Verprolin homology, Cofilin homology, Acidic) domain of WASp at the plasma membrane by a ligand technique using rapamycin as an intermediate is not sufficient to elicit efficient Arp2/3 complex-mediated actin polymerization. Other domains of WASp, in particular the proline-rich domain, are required for the formation of actin-rich structures. An in vitro analysis demonstrates that the proline-rich domain of WASp binds VASP with an affinity of approximately 10(6) M(-1). In addition, WASp and VASP both accumulate in actin-rich phagocytic cups. Finally, in a reconstituted motility medium, VASP enhances actin-based propulsion of WASp-coated beads in a fashion reminiscent of its effect on Listeria movement. We propose that VASP and WASp cooperation is essential in stimulating actin assembly and membrane protrusion at the leading edge.

Anatomic and biomechanical properties of human lumbar dura mater.

Determinants of dural defects subsequent to deliberate or accidental dural puncture include the equipment, techniques, and the inherent anatomic and biomechanical properties of dura mater. These properties were studied in specimens of human and canine lumbar dura mater in an attempt to delineate the structure of the tissue and to characterize its behavior in biomechanical terms. Human dura had a longitudinal orientation on gross appearance, and was confirmed microscopically to be composed of longitudinal lamella of collagen and elastin fibers. Longitudinal tensile strength and stiffness were greater than transverse tensile strength and stiffness, which is consistent with the dura's apparent anatomic structure and functional requirements. Additional biomechanical testing of the dura demonstrated the property of relaxation which is a characteristic of a viscoelastic material. Significant differences were observed between human and canine dural properties, suggesting limited value of this animal model. Integration of these observed anatomic and biomechanical properties of the lumbar dura provides a greater understanding of dural puncture and may explain previous and often confusing clinical and experimental findings.

Identification of the protein products of the rrnC, ilv, rho region of the Escherichia coli K-12 chromosome.

Two methods have been used to identify the protein products of the Escherichia coli K-12 ilv region at 84 min and the flanking rrnC (counterclockwise) and rho (clockwise) loci. First, a set of lambda dilv specialized transducing phages, including some phages that carry rho and others that carry part of rrnC, was used to infect UV irradiated cells. The proteins produced by the infecting lambda dilv phage were selectively labelled with radioactivity amino acids and identified by SDS gel electrophoresis and autoradiography. Second, restriction enzyme fragments were cloned from the lambda dilv phage into pBR322 and the plasmid specific gene products produced in maxicells were similarly identified by SDS gel electrophoresis and autoradiography. The proteins produced were correlated with specific genes and restriction enzyme fragments present in the lambda dilv phage and the pBR322 derivatives. Several ilv gene products that have previously been refractory to protein purification attempts have been identified for the first time by this technique. The presence of mutations at the ilvO site is shown to activate the cryptic ilvG gene and to result in the production of a 62,000 dalton protein. A 15,000 dalton protein of unknown function is synthesized from a DNA segment between ilv and rrnC. The rho gene was cloned from lambda dilv phage into pBR322 and shown to be dominant to a rho mutation on the host chromosome. The rho gene product and four additional proteins coded by genes near or between rho and ilv have been detected.

Mapping of ilvO loci of Escherichia coli K-12 with bacteriophage lambda dilv.

A set of lambda dilv phage have been used in a deletion mapping procedure to determine the location of two previously characterized ilvO alleles. In contrast to earlier conclusions derived from three-factor crosses and episome-shortening techniques with phage P1, the order found is ilvG-ilvO-ilvEDA. A three-factor cross with phage P1 is described that is not consistent with this location for an ilvO allele. Further analysis of this particular three-factor cross revealed than an artifact attributable to a mutual syntrophism had skewed the apparent frequency of inheritance of the ilvO locus. The role of mutual syntrophism is discussed as a source of mapping errors for the ilvO locus. The value of this set of lambda dilv phage and this mapping procedure for obtaining comparatively unambiguous data on the locations of the ilv structural and regulatory genes is demonstrated.

Deletion mapping of the ilvGOEDAC genes of Escherichia coli K-12.

A set of lambdadilv phage has been examined that carry overlapping segments of isoleucine-valine structural and regulatory genes derived from the ilv cluster at 83 min on the Escherichia coli K-12 chromosome. The ilv genes present in these phage, and their order, have been determined by transduction of auxotrophs, escape synthesis, and deletion mapping. The order of ilv genes in the phage, and hence the order in the host chromosome, was found to be ilvG-ilvO-ilvEDA-ilvC. Lysogens containing lambdadilv phage were constructed for dominance analysis of regulatory mutations in the ilvO and ilvA genes. The ilvO671 allele is cis-dominant to ilvO+, while the ilvA538 allele is trans-recessive to ilvA+. Thus, the ilvO gene, that is identified by cis-dominant regulatory mutations that result in increased ilvG and ilvEDA expression, is situated between and may be contiguous with ilvG and ilvEDA.