Physicochemical characterization and antimicrobial properties of rhamnolipids produced by Pseudomonas aeruginosa 47T2 NCBIM 40044

7 pages, 2 figures, 3 tables.-- PMID: 12474254 [PubMed].-- Available online Dec 3, 2002.Pseudomonas aeruginosa 47T2, grown in submerged culture with waste frying oil as a carbon source, produced a mixture of rhamnolipids with surface activity. Up to 11 rhamnolipid homologs (Rha-Rha-C8-C10; Rha-C10-C8/Rha-C8-C10;Rha-Rha-C8-C12:1; Rha-Rha-C10-C10; Rha-Rha-C10-C12:1; Rha-C10-C10; Rha-Rha-C10-C12/Rha-Rha-C12-C10; Rha-C10-C12:1/Rha-C12:1-C10; Rha-Rha-C12:1-C12; Rha-Rha-C10-C14:1; Rha-C10-C12/Rha-C12-C10) were isolated from cultures of P. aeruginosa 47T2 from waste frying oil and identified by HPLC-MS analysis. This article deals with the production, isolation, and chemical characterization of the rhamnolipid mixture RL47T2. The physicochemical and biological properties of RL47T2 as a new product were also studied. Its surface tension decreased to 32.8 mN/m; and the interfacial tension against kerosene to 1 mN/m. The critical micellar concentration for RL47T2 was 108.8 mg/mL. The product showed excellent antimicrobial properties. Antimicrobial activity was evaluated according to the minimum inhibitory concentration (MIC), the lowest concentration of an antimicrobial agent that inhibits development of visible microbial growth. Low MIC values were found for bacteria Serratia marcescens (4 g/mL), Enterobacter aerogenes (8 g/mL), Klebsiella pneumoniae (0.5 g/mL), Staphylococcus aureus and Staphylococcus epidermidis (32 g/mL), Bacillus subtilis (16 g/mL), and phytopathogenic fungal species: Chaetonium globosum (64 g/mL), Penicillium funiculosum (16 g/mL), Gliocadium virens (32 g/mL) and Fusarium solani (75 g/mL).Finnancial support by the CIRIT and CICYT; Grant Number: 199956R 00024, PPQ-2000-0105-P4-03, REN 2001-3224.Peer reviewe

Mixed monolayer of DPPC and lysine-based cationic surfactants: An investigation into the antimicrobial activity

In this paper, we report studies which aim to elucidate the mechanisms involved in the antimicrobial activity of three cationic lysine-based surfactants: LLM, LALM, and C6 (LL)2. To this end, a simple membrane model (i.e., 1,2-dipalmitoyl-sn-phosphatidylcholine, DPPC) was used to explore the monolayer properties at the air/liquid interface. Compression π-A isotherms of mixtures of DPPC/lysine surfactants at different pH showed an expansion of the DPPC monolayer, suggesting cationic lysine surfactant/DPPC interactions, which strongly depend on surfactant structure and hydrophobic interactions. Antimicrobial activity of the three surfactants has also been assessed with transmission electron microscopy, observing the effects on Staphylococcus aureus and Escherichia coli. The three surfactants caused various kinds of damage to the bacteria tested, such as structural alterations, leakage of internal material, and cell destruction.Authors have been supported by the CICYT Spanish Research Agency under the projects CTQ2009-14151-C02-01 and CTQ2010-14897 and by AGAUR Research Agency of the Generalitat de Catalunya under the project 2009 SRG 246Peer reviewe

Factores predisponentes y complicaciones maternas-neonatales de la anemia en el embarazo.

It was fulfilled an observational analytic research of cases and controls, identifying factors and maternal-neonatal complications. The research variables were: intergenesic interval level of scholarship, pregnancy diseases, maternal and neonatal complications. There were identified as predisposed factors of pregnancy anemia, the intergenesic short maternal (73.2%) and the low level of scholarship (63.41%). The urinary tract infection and vaginal Candida were associated to anemia in 85.4% and 48.8% respectively. The non sufficient winning of maternal weight 83.6% and the cervix vaginal infections 73.1%, were the complications that appeared, while the low weight at birth, with 92.6%, was the representative neonatal complication.Se realizó un estudio observacional analítico de casos y controles indetificándose factores predisponentes y complicaciones maternas-neonatales. La variable es estudio fueron: intervalo intergenésico, nivel de escolaridad, enfermedades dependientes del embarazo, complicaciones maternas y complicaciones neonatales. Se identificaron como factores predisponentes de la anemia en el embarazo, el intervalo intergenésico corto (73,2%) y el bajo nivel de escolaridad (63,41). La infección urinaria y la vaginitis por cándidas estuvieron asociadas a la anemia en un 85,4 % y 48,8 % respectivamente. La ganancia insuficiente de peso materno 83,6 % y las infecciones cérvico-vaginales 73,1 % fueron las complicaciones que se encontraron, mientras que el bajo peso al nacer 92,6% fue la complicación neonatal representativa.

DNA gel particles: An overview

A general understanding of interactions between DNA and oppositely charged compounds forms the basis for developing novel DNA-based materials, including gel particles. The association strength, which is altered by varying the chemical structure of the cationic cosolute, determines the spatial homogeneity of the gelation process, creating DNA reservoir devices and DNA matrix devices that can be designed to release either single- (ssDNA) or double-stranded (dsDNA). This review covers recent developments on the topic of DNA gel particles formed in water-water emulsion-type interfaces. The degree of DNA entrapment, particle morphology, swelling/dissolution behaviour and DNA release responses are discussed as a function of the nature of the cationic agent used. On the basis of designing DNA gel particles for therapeutic purposes, recent studies on the determination of the surface hydrophobicity, the haemolytic and the cytotoxic assessments of the obtained DNA gel particles have been also reported

Factores predisponentes de embarazo en adolescentes de nuevo turumo. Venezuela. 2007- 2008

RESUMEN Introducción: el embarazo en la adolescencia es un problema de salud mundial. En el mundo existen más de mil millones de adolescentes que aportan anualmente 15 millones de partos y de ellos 80% son pertenecientes a países en vías de desarrollo. Objetivo: identificar factores predisponentes de embarazo en adolescentes de Nuevo Turumo, Venezuela desde agosto de 2007 a agosto de 2008. Material y Métodos: se realizó un estudio descriptivo de corte transversal con 32 embarazadas adolescentes de Nuevo Turumo desde agosto de 2007 a agosto de 2008 seleccionadas según los criterios de inclusión y exclusión. Se utilizaron métodos teóricos (análisis, síntesis e histórico lógico) y empíricos (entrevista directa). Para el análisis de resultados se utilizó el paquete estadístico SPSS 11.5 y se calcularon frecuencias absolutas y relativas. Resultados: predominaron las embarazadas en la adolescencia tardía; las adolescentes casadas sobre las solteras; la escolaridad correspondió a la secundaria terminada y sin terminar; la menarquia en la adolescencia temprana, inicio de las relaciones sexuales en la adolescencia media; pocos conocimientos y utilización de los métodos anticonceptivos, no vinculación al trabajo. Acceso a los medios de comunicación y tiempo libre dedicado mayormente a la televisión e Internet. Conclusiones: los factores predisponentes de embarazo en las adolescentes de Nuevo Turumo fueron: predominio de secundaria básica terminada como nivel escolar; presencia de la menarquia en la adolescencia temprana; inicio de las relaciones sexuales en la adolescencia media; pocos conocimientos y utilización de los métodos anticonceptivos; no vinculación al trabajo y acceso a los medios de comunicación y tiempo libre, dedicado mayormente a la televisión e Internet.  Palabras clave: adolescente, embarazo, factores predisponentes. </p

Galaxy clusters and groups in the ALHAMBRA Survey

We present a catalogue of 348 galaxy clusters and groups with $0.2<z<1.2$ selected in the 2.78 $deg^2$ ALHAMBRA Survey. The high precision of our photometric redshifts, close to $1\%$, and the wide spread of the seven ALHAMBRA pointings ensure that this catalogue has better mass sensitivity and is less affected by cosmic variance than comparable samples. The detection has been carried out with the Bayesian Cluster Finder (BCF), whose performance has been checked in ALHAMBRA-like light-cone mock catalogues. Great care has been taken to ensure that the observable properties of the mocks photometry accurately correspond to those of real catalogues. From our simulations, we expect to detect galaxy clusters and groups with both $70\%$ completeness and purity down to dark matter halo masses of $M_h\sim3\times10^{13}\rm M_{\odot}$ for $z<0.85$. Cluster redshifts are expected to be recovered with $\sim0.6\%$ precision for $z<1$. We also expect to measure cluster masses with $\sigma_{M_h|M^*_{CL}}\sim0.25-0.35\, dex$ precision down to $\sim3\times10^{13}\rm M_{\odot}$, masses which are $50\%$ smaller than those reached by similar work. We have compared these detections with previous optical, spectroscopic and X-rays work, finding an excellent agreement with the rates reported from the simulations. We have also explored the overall properties of these detections such as the presence of a colour-magnitude relation, the evolution of the photometric blue fraction and the clustering of these sources in the different ALHAMBRA fields. Despite the small numbers, we observe tentative evidence that, for a fixed stellar mass, the environment is playing a crucial role at lower redshifts (z$<$0.5).Comment: Accepted for publication in MNRAS. Catalogues and figures available online and under the following link: http://bascaso.net46.net/ALHAMBRA_clusters.htm

‘Costa da Morte’ ataxia is spinocerebellar ataxia 36: clinical and genetic characterization

Spinocerebellar ataxia 36 has been recently described in Japanese families as a new type of spinocerebellar ataxia with motor neuron signs. It is caused by a GGCCTG repeat expansion in intron 1 of NOP56. Family interview and document research allowed us to reconstruct two extensive, multigenerational kindreds stemming from the same village (Costa da Morte in Galicia, Spain), in the 17th century. We found the presence of the spinocerebellar ataxia 36 mutation co-segregating with disease in these families in whom we had previously identified an ∼0.8 Mb linkage region to chromosome 20 p. Subsequent screening revealed the NOP56 expansion in eight additional Galician ataxia kindreds. While normal alleles contain 5–14 hexanucleotide repeats, expanded alleles range from ∼650 to 2500 repeats, within a shared haplotype. Further expansion of repeat size was frequent, especially upon paternal transmission, while instances of allele contraction were observed in maternal transmissions. We found a total of 63 individuals carrying the mutation, 44 of whom were confirmed to be clinically affected; over 400 people are at risk. We describe here the detailed clinical picture, consisting of a late-onset, slowly progressive cerebellar syndrome with variable eye movement abnormalities and sensorineural hearing loss. There were signs of denervation in the tongue, as well as mild pyramidal signs, but otherwise no signs of classical amyotrophic lateral sclerosis. Magnetic resonance imaging findings were consistent with the clinical course, showing atrophy of the cerebellar vermis in initial stages, later evolving to a pattern of olivo-ponto-cerebellar atrophy. We estimated the origin of the founder mutation in Galicia to have occurred ∼1275 years ago. Out of 160 Galician families with spinocerebellar ataxia, 10 (6.3%) were found to have spinocerebellar ataxia 36, while 15 (9.4%) showed other of the routinely tested dominant spinocerebellar ataxia types. Spinocerebellar ataxia 36 is thus, so far, the most frequent dominant spinocerebellar ataxia in this region, which may have implications for American countries associated with traditional Spanish emigration

The impact from survey depth and resolution on the morphological classification of galaxies

We consistently analyse for the first time the impact of survey depth and spatial resolution on the most used morphological parameters for classifying galaxies through non-parametric methods: Abraham and Conselice-Bershady concentration indices, Gini, M20moment of light, asymmetry, and smoothness. Three different non-local data sets are used, Advanced Large Homogeneous Area Medium Band Redshift Astronomical (ALHAMBRA) and Subaru/XMMNewton Deep Survey (SXDS, examples of deep ground-based surveys), and Cosmos Evolution Survey (COSMOS, deep space-based survey). We used a sample of 3000 local, visually classified galaxies, measuring their morphological parameters at their real redshifts (z ~ 0). Then we simulated them to match the redshift and magnitude distributions of galaxies in the non-local surveys. The comparisons of the two sets allow us to put constraints on the use of each parameter for morphological classification and evaluate the effectiveness of the commonly used morphological diagnostic diagrams. All analysed parameters suffer from biases related to spatial resolution and depth, the impact of the former being much stronger. When including asymmetry and smoothness in classification diagrams, the noise effects must be taken into account carefully, especially for ground-based surveys. M20 is significantly affected, changing both the shape and range of its distribution at all brightness levels. We suggest that diagnostic diagrams based on 2-3 parameters should be avoided when classifying galaxies in ground-based surveys, independently of their brightness; for COSMOS they should be avoided for galaxies fainter than F814 = 23.0. These results can be applied directly to surveys similar to ALHAMBRA, SXDS and COSMOS, and also can serve as an upper/lower limit for shallower/deeper ones.MP acknowledge financial support from JAE-Doc programme of the Spanish National Research Council (CSIC), co-funded by the European Social Fund. This research was supported by the Junta de Andalucia through project TIC114, and the Spanish Ministry of Economy and Competitiveness (MINECO) through projects AYA2010-15169, AYA2013-42227-P, and AYA2013-43188-P.Peer Reviewe