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Pseudomonas aeruginosa is one of the most worrisome infectious bacteria due to its intrinsic and acquired resistance against several antibiotics and the recalcitrance of its infections; hence, the development of novel antimicrobials effective against multidrug-resistant P. aeruginosa is mandatory. In this work, silver nanoparticles obtained by green synthesis using a leaf extract and fungi were tested against a battery of clinical strains from cystic fibrosis, pneumonia and burnt patients, some of them with multidrug resistance. Both nanoparticles showed a potent antibacterial effect, causing severe damage to the cell wall, membrane and DNA, and inducing the production of reactive oxygen species. Moreover, the nanoparticles derived from fungi showed synergistic antibacterial effects with the antibiotics meropenem and levofloxacin for some clinical strains and both kinds of nanoparticles were nontoxic for larvae of the moth Galleria mellonella, encouraging further research for their implementation in the treatment of P. aeruginosa infections.

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The indirect fluorescent antibody test (IFAT) is the most frequently used test to conduct seroepidemiological studies so far, and it is regarded as the "gold standard" test for the serological diagnosis of bovine babesiosis. The aim of the present study was to compare the enzyme-linked immunosorbent assay (ELISA) and the rapid immunochromatography test (ICT) for use in the serological diagnosis of cattle exposed to B. bovis in Mexico. The evaluation of test performance was carried out with 30 positive and 30 negative reference sera. A total of 72 bovine sera samples collected from cattle in a region with endemic bovine babesiosis were analyzed by ELISA and ICT, and the results were compared with those of IFAT. Kappa value (k) was also calculated to determine the agreement between tests. The sensitivity and specificity of ELISA for detecting antibodies against B. bovis were 87% (26/30) and 80% (24/30), respectively. The sensitivity and specificity of ICT for detecting antibodies against B. bovis were 90% (27/30) and 83.3% (25/30), respectively. The overall concordance determined for ELISA and ICT was 94.4% (68/72) and 98.6% (71/72), respectively, when the results were compared with those of IFAT. ICT was more sensitive and specific in this comparative study, showing good strength of agreement (k = 0.79) with respect to IFAT. ICT combines a strip-based assay system that is fast, practical, and sensitive for detection of antibodies to B. bovis, which suggests that it could be applied in the field without requiring any laboratory equipment for its use and interpretation of test results.

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The causative agents of Babesiosis are intraerythrocytic protozoa of the genus Babesia. Babesia parasites are present around the world, affecting several mammals including humans, pets and livestock, hence its medical and veterinary relevance. Babesia spp. detection in its invertebrate host is a main point in understanding the biology of the parasite to acquire more knowledge on the host-Babesia-vector interactions, as increasing knowledge of the Babesia lifecycle and babesiosis epidemiology can help prevent babesiosis outbreaks in susceptible mammals. The aim of the present review is to highlight the newest findings in this field, based on a bibliographic compilation of research studies recently carried out for the detection of the main Babesia species found in tick vectors affecting mammalian hosts, including the different tick stages such as adult ticks, larvae, nymphs and eggs, as well as the detection method implemented: microscopic tools for parasite identification and molecular tools for parasite DNA detection by conventional PCR, nested-PCR, PCR-RFLP, PCR-RLB hybridization, real time-PCR, LAMP and RAP assays. Although molecular identification of Babesia parasites has been achieved in several tick species and tissue samples, it is still necessary to carry out transmission experiments through biological models to confirm the vectorial capacity of various tick species.

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PURPOSE: The synthetic peptide GK-1 potentiates protective immunity elicited by the influenza vaccine in mice. In order to understand its adjuvant properties, this study was designed to determine the impact of GK-1 on gene expression and phagocytosis of peritoneal macrophages (PMa). METHODS: Increased gene expression of chemokines involved in leukocyte recruitment and of pro-inflammatory mediators was detected by microarray analysis of control and GK-1 treated PMa macrophages. The expression profile was subsequently confirmed by Multiplex Immunoassays analysis to measure cytokines levels, flow cytometer to describe M1/M2 surface markers and an assay to evaluate their phagocytic activity. RESULTS: Treatment of PMa with GK-1 results in development to the classically activated M1 functional macrophage subpopulation with increased expression of the CCL3 and CXCLO2 chemokines, IL-6 and TNF-α proinflammatory cytokines with a concomitant increase in the levels of NO, accompanied by the expression of modulatory factors that downregulate the inflammatory phenotype. GK-1 treated PMa significantly increased their phagocytic activity. CONCLUSION: GK-1 classical activated with enhanced phagocitic capacity may underlie in the increased specific immunity induced when concomitant administered with other antigens.

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Mycobacterium tuberculosis has developed resistance to anti-tuberculosis first-line drugs. Multidrug-resistant strains complicate the control of tuberculosis and have converted it into a worldwide public health problem. Mutational studies of target genes have tried to envisage the resistance in clinical isolates; however, detection of these mutations in some cases is not sufficient to identify drug resistance, suggesting that other mechanisms are involved. Therefore, the identification of new markers of susceptibility or resistance to first-line drugs could contribute (1) to specifically diagnose the type of M. tuberculosis strain and prescribe an appropriate therapy, and (2) to elucidate the mechanisms of resistance in multidrug-resistant strains. In order to identify specific genes related to resistance in M. tuberculosis, we compared the gene expression profiles between the pansensitive H37Rv strain and a clinical CIBIN:UMF:15:99 multidrug-resistant isolate using microarray analysis. Quantitative real-time PCR confirmed that in the clinical multidrug-resistant isolate, the esxG, esxH, rpsA, esxI, and rpmI genes were upregulated, while the lipF, groES, and narG genes were downregulated. The modified genes could be involved in the mechanisms of resistance to first-line drugs in M. tuberculosis and could contribute to increased efficiency in molecular diagnosis approaches of infections with drug-resistant strains.

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1. The stress-gradient hypothesis (SGH) states that environmental stress modulates species interactions, causing a shift from negative interactions to net positive interactions with increasing stress. 2. Potentially, this modulation of species interactions could in turn influence biodiversity-ecosystem function (B-EF) relationships along stress gradients. Although the SGH has been extensively discussed in plant community ecology in the past two decades, it has received little attention from animal ecologists. 3. To explore whether the SGH could be applied to animal communities, we conducted a litter decomposition experiment with aquatic detritivorous invertebrates in which we manipulated litter quality and measured species interactions along this resource quality gradient. Litter quality was manipulated by presenting detritivores with leaves of plant species varying in specific leaf area and decomposition rate in streams. 4. We found a switch from negative to neutral interactions with increasing resource quality stress, in line with the SGH. However, by re-examining other published results with aquatic detritivores from the perspective of the SGH, we found that a diversity of patterns seem to characterize detritivore interactions along stress gradients. 5. Although the basic pattern proposed by the SGH may not apply to animal systems in general, we show that aquatic detritivore interactions do change along stress gradients, which underlines the importance of incorporating environmental stressors more explicitly in B-EF research.

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En el siguiente artículo se hace una revisión del proceso de envejecimiento de la región perioral así como de las principales técnicas descritas para su rejuvenecimiento dentro de las que se incluyen los peelings químicos, el uso de láser, rellenos faciales y toxina botulínica tipo A...

The following article is a review of the aging process of the perioral region and of the main techniques for rejuvenation described including chemical peels, laser use, facial fillers and botulinum toxin type A...

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Los trabajadores universitarios en su mayoría laboran en ambientes donde están expuestos a diversos factores de riesgo, particularmente en el ámbito de los laboratorios, debido al microclima laboral de los mismos, lo que se conoce como procesos peligrosos. El objetivo fue identificar los procesos peligrosos presentes en una universidad venezolana, con la finalidad de elaborar el panorama de factores de riesgo de las áreas evaluadas. La investigación fue descriptiva, de corte transversal, de carácter exploratorio. La población laboral constó de 81 trabajadores (personal docente, administrativo y obrero), distribuidos en 26 áreas, consideradas de mayor riesgo, de las cuales fueron evaluadas 15 (65,38%). Los riesgos químicos (30,6%), seguidos de los mecánismos (28,4%) y los físicos (19,8%), fueron los más relevantes. Mediante el panorama de factores de riesgo se pudieron identificar como las áreas de mayor peligrosidad a: mantenimiento, laboratorio de suelos, laboratorio de química II las cuales representan el 20% de los sectores evaluados, y son a su vez las que cuentan con mayor número de trabajadores y por ende, el grado de peligrosidad para la población total es mayor, tomando como criterio el producto dado por el número de trabajadores, el número de horas laboradas y el promedio ponderado del factor de riesgo. Las condiciones de trabajo en general de la universidad evaluada, son inadecuadas, debido a la presencia de un porcentaje importante de procesos peligrosos en las diferentes áreas de trabajo.

The university workers in their majority toil in atmospheres where they are exposed to diverse factors of risks, particularly in the scope of the laboratories, had to the labor microclimate of such, which he knows himself like dangerous processes. The objetive was to identify dangerous processes the present ones in a Venezuelan University, with the purpose of elaborating the panorama of factors of risk of the evaluated areas. The investigation was descriptive, of cross section, exploratory character. The labor population consisted of 81 workers (personal educational, administrative and working), distributed in 26 areas, considered of greater risk, of which 15 were evaluated (65.38%). The chemical risks (30.6%), followed of the mechanics (28.4%) and the physicists, (19.8%), were most excellent. By means of the panorama of factors of risk could be identified like the areas of greater danger a: ground maintenance, laboratory, laboratory of chemistry II which represent 20% of the evaluated sectors, and are as well those that count on greater number of workers and therefore, the degree of danger for the total population is greater, taking like criterion the product given by the number of workers, the number of toiled hours and the weighed average of the risk factor. The conditions of work in general of the evaluated University, are inadequate, due to the presence of an important percentage of dangerous processes in the different work areas.

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Background: Vascular anomalies are prevalent in the general population and may produce significant impairment in quality of life. In recent years, minimally invasive interventional radiology techniques have become an efficient alternative for the treatment of these patients. The aim of this study was to present our experience in the management of vascular malformations with such techniques at Clínica Alemana in Santiago, Chile, and assess the satisfaction of patients with this management. Material and Methods: Evaluation of the follow-up of patients with vascular malformations treated in the Interventional Radiology Unit at our center since June - 2006 to June - 2009. Patients were classified according to the hemodynamics of the lesions (high vs low-flow). Complications and patient satisfaction with the treatment were assessed. Results: Eighty-seven patients (253 procedures) were included in the study, 36 men and 51 women, all with complete follow-up during the period of the study. Their average age was 20.6 years. In over 50 percent of the patients the vascular anomaly was located on the face or the lower extremities. Twenty-eight percent (25 patients) had a high-flow malformation (pure or mixed) and 62 (72 percent) had a low-flow lesion (vascular malformation, lymphangioma or mixed). On average, each patient underwent 2.9 procedures (1-10). There were 4 major complications (1.65 percent), one of which was predominantly cosmetic with necrosis in the area of the lesion. The average satisfaction rate was 7.95 (on a rating scale of 1 to 10). Satisfaction was significantly higher in patients with low-flow malformations (8.27) than in those with high-flow lesions (7.16). (p < 0.05) Discussion: Treatment of vascular malformations using interventional radiology techniques is an effective alternative, with good prospects of clinical improvement, patient satisfaction and low complication rates.

Introducción: Las anomalías vasculares son una patología frecuente en la población general, y son causa de deterioro de la calidad de vida de los pacientes que las padecen. En los últimos años, las técnicas mínimamente invasivas de radiología intervencional se han convertido en una alternativa eficaz para el tratamiento de estos pacientes. El objetivo del presente estudio es mostrar nuestra experiencia en el manejo de malformaciones vasculares con estas técnicas en la Clínica Alemana de Santiago y evaluar la satisfacción de los pacientes con este manejo. Material y Métodos: Evaluación del seguimiento de todos los pacientes con malformaciones vasculares tratados en la Unidad de Radiología Intervencional desde el año 2006 hasta junio del año 2009. Los pacientes fueron clasificados en base a la hemodinamia de la malformación vascular (alto flujo vs. bajo flujo). Se evaluaron las complicaciones, y se realizó una encuesta sobre la satisfacción de los pacientes con el tratamiento. Resultados: Ochenta y siete pacientes (253 procedimientos) fueron incluidos en el estudio, 36 hombres y 51 mujeres, todos con seguimiento completo en este periodo. La edad promedio de ellos fue de 20,6 años. En más del 50 por ciento de los pacientes la anomalía vascular se ubicó en la cara o extremidades inferiores. Un 28 por ciento (25 pacientes) presentó malformación de alto flujo (pura o mixta) y 72 por ciento (62 pacientes) de bajo flujo (malformaciones vasculares, linfangiomas o mixtas). En promedio, cada paciente se realizó 2,9 procedimientos (1-10). Del total de procedimientos realizados, hubo 4 complicaciones mayores (1,65 por ciento), una de ellas con secuelas estéticas producto de necrosis de la zona. El promedio de satisfacción fue de un 7,95 en una escala de 1 a 10, siendo significativamente mayor en pacientes con malformaciones de bajo flujo (8,27) que en los de alto flujo (7,16) (p < 0.05)...

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Several aldehyde dehydrogenase (ALDH) complexes have been purified from the membranes of acetic acid bacteria. The enzyme structures and the chemical nature of the prosthetic groups associated with these enzymes remain a matter of debate. We report here on the molecular and catalytic properties of the membrane-bound ALDH complex of the diazotrophic bacterium Gluconacetobacter diazotrophicus. The purified ALDH complex is a heterodimer comprising two subunits of 79.7 and 50 kDa, respectively. Reversed-phase high-pressure liquid chromatography (HPLC) and electron paramagnetic resonance spectroscopy led us to demonstrate, for the first time, the unequivocal presence of a pyrroloquinoline quinone prosthetic group associated with an ALDH complex from acetic acid bacteria. In addition, heme b was detected by UV-visible light (UV-Vis) spectroscopy and confirmed by reversed-phase HPLC. The smaller subunit bears three cytochromes c. Aliphatic aldehydes, but not formaldehyde, were suitable substrates. Using ferricyanide as an electron acceptor, the enzyme showed an optimum pH of 3.5 that shifted to pH 7.0 when phenazine methosulfate plus 2,6-dichlorophenolindophenol were the electron acceptors. Acetaldehyde did not reduce measurable levels of the cytochrome b and c centers; however, the dithionite-reduced hemes were conveniently oxidized by ubiquinone-1; this finding suggests that cytochrome b and the cytochromes c constitute an intramolecular redox sequence that delivers electrons to the membrane ubiquinone.

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