Primer reporte de cepas de Enterobacter spp productoras de metalobetalactamasas de Venezuela

Clinical strains of Enterobacter were isolated from Cumana's Central Hospital in Venezuela, and classified as E. cloacae (21), E. aerogenes (7), E. intermedium (1), E. sakazakii (1) and three unclassified. The strains showed high levels of resistance, especially to SXT (58.1%), CRO (48.8%), CAZ (46.6%), PIP (46.4%), CIP (45.2%) and ATM (43.3%). This is the first report for South America of blaVIM-2 in two E. cloacae and one Enterobacter sp., which also showed multiple mechanisms of resistance. Both E. cloacae showed blaTEM-1, but only one showed blaCTX-M-15 gene, while no blaSHV was detected.Cepas clínicas de Enterobacter fueron aisladas del Hospital central de Cumaná en Venezuela, y se clasificaron como E. cloacae (21), E. aerogenes (7), E. intermedium (1), E. sakazakii (1) y 3 sin clasificar. Las cepas mostraron altos niveles de resistencia, especialmente a SXT (58.1%), CRO (48.8%), CAZ (46.6%), PIP (46.4%), CIP (45.2%) and ATM (43.3%). Este es el primer reporte de América del Sur de blaVIM-2 en dos cepas de E. cloacae y una de Enterobacter sp., las cuales también mostraron múltiples mecanismos de resistencia. Ambas especies de E. cloacae mostraron genes blaTEM-1, pero solo una mostro el gen blaCTX-M-15, mientras que blaSHV no fue detectado

Intercellular Trafficking of Gold Nanostars in Uveal Melanoma Cells for Plasmonic Photothermal Therapy

Efficient plasmonic photothermal therapies (PPTTs) using non-harmful pulse laser irradiation at the near-infrared (NIR) are a highly sought goal in nanomedicine. These therapies rely on the use of plasmonic nanostructures to kill cancer cells while minimizing the applied laser power density. Cancer cells have an unsettled capacity to uptake, retain, release, and re-uptake gold nanoparticles, thus offering enormous versatility for research. In this work, we have studied such cell capabilities for nanoparticle trafficking and its impact on the effect of photothermal treatments. As our model system, we chose uveal (eye) melanoma cells, since laser-assisted eye surgery is routinely used to treat glaucoma and cataracts, or vision correction in refractive surgery. As nanostructure, we selected gold nanostars (Au NSs) due to their high photothermal efficiency at the near-infrared (NIR) region of the electromagnetic spectrum. We first investigated the photothermal effect on the basis of the dilution of Au NSs induced by cell division. Using this approach, we obtained high PPTT efficiency after several cell division cycles at an initial low Au NS concentration (pM regime). Subsequently, we evaluated the photothermal effect on account of cell division upon mixing Au NS-loaded and non-loaded cells. Upon such mixing, we observed trafficking of Au NSs between loaded and non-loaded cells, thus achieving effective PPTT after several division cycles under low irradiation conditions (below the maximum permissible exposure threshold of skin). Our study reveals the ability of uveal melanoma cells to release and re-uptake Au NSs that maintain their plasmonic photothermal properties throughout several cell division cycles and re-uptake. This approach may be readily extrapolated to real tissue and even to treat in situ the eye tumor itself. We believe that our method can potentially be used as co-therapy to disperse plasmonic gold nanostructures across affected tissues, thus increasing the effectiveness of classic PPTT

The role of cognitive dysfunction in the symptoms and remission from depression.

The disability and burden associated with major depression comes only in part from its affective symptoms; cognitive dysfunctions associated with depression also play a crucial role. Furthermore, these cognitive impairments during depression are manifold and multilevel affecting elementary and more complex cognitive processes equally. Several models from different directions tried to evaluate, conceptualize and understand the depth and magnitude of cognitive dysfunctions in depression and their bidirectional interactions with other types of depressive symptomatology including mood symptoms. In the current review, we briefly overview different types of cognitive symptoms and deficits related to major depression including hot and cold as well as trait- and state-like cognitive alterations and we also describe current knowledge related to the impact of cognitive impairments on the course and outcomes of depression including remission, residual symptoms, function, and response to treatment. We also emphasize shortcomings of currently available treatments for depression in sufficiently improving cognitive dysfunctions and point out the need for newer pharmacological approaches especially in cooperation with psychotherapeutic interventions

Rentabilidad privada de las granjas porcinas en el sur del Estado de México

La rentabilidad privada y la eficiencia de los costos privados son indicadores de competitividad en las granjas porcinas. El presente estudio se realizó en el Sur del Estado de México en 2006, y se basó en información proveniente de sesenta porcicultores de traspatio, dos de granjas semitecnificadas y una tecnificada. La Matriz de Análisis de Política fue el método usado y consiste en una serie de matrices de coeficientes técnicos y de precios de los insumos y del producto, con los que se derivó la matriz de presupuesto privado. Los tres sistemas productivos presentaron una rentabilidad positiva a precios privados, que variaron de 11 a 13 %. Asimismo, las relaciones de costo privado se situaron entre 0.53 y 0.58, lo que sugiere una alta competitividad. Para 2006 se concluyó que la producción porcícola de los sistemas mencionados permitió pagar el valor de mercado de factores internos, incluyendo la tasa de retorno normal del capital, y que la actividad productiva fue redituable en función de los precios recibidos y pagados

Dengue: a continuing global threat.

Dengue fever and dengue haemorrhagic fever are important arthropod-borne viral diseases. Each year, there are ∼50 million dengue infections and ∼500,000 individuals are hospitalized with dengue haemorrhagic fever, mainly in Southeast Asia, the Pacific and the Americas. Illness is produced by any of the four dengue virus serotypes. A global strategy aimed at increasing the capacity for surveillance and outbreak response, changing behaviours and reducing the disease burden using integrated vector management in conjunction with early and accurate diagnosis has been advocated. Antiviral drugs and vaccines that are currently under development could also make an important contribution to dengue control in the future

Robustness of optimal channel reservation using handover prediction in multiservice wireless networks

The aim of our study is to obtain theoretical limits for the gain that can be expected when using handover prediction and to determine the sensitivity of the system performance against different parameters. We apply an average-reward reinforcement learning approach based on afterstates to the design of optimal admission control policies in mobile multimedia cellular networks where predictive information related to the occurrence of future handovers is available. We consider a type of predictor that labels active mobile terminals in the cell neighborhood a fixed amount of time before handovers are predicted to occur, which we call the anticipation time. The admission controller exploits this information to reserve resources efficiently. We show that there exists an optimum value for the anticipation time at which the highest performance gain is obtained. 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Not All Missed Doses Are the Same: Sustained NNRTI Treatment Interruptions Predict HIV Rebound at Low-to-Moderate Adherence Levels

Background: While the relationship between average adherence to HIV potent antiretroviral therapy is well defined, the relationship between patterns of adherence within adherence strata has not been investigated. We examined medication event monitoring system (MEMS) defined adherence patterns and their relation to subsequent virologic rebound. Methods and Results: We selected subjects with at least 3-months of previous virologic suppression on a non-nucleoside reverse transcriptase inhibitor (NNRTI)-based regimen from two prospective cohorts in France and North America. We assessed the risk of virologic rebound, defined as HIV RNA of >400 copies/mL according to several MEMS adherence measurements. Seventy two subjects were studied, five of them experienced virologic rebound. Subjects with and without virologic rebound had similar baseline characteristics including treatment durations, regimen (efavirenz vs nevirapine), and dosing schedule. Each 10% increase in average adherence decreased the risk of virologic rebound (OR = 0.56; 95% confidence interval (CI) [0.37, 0.81], P<0.002). Each additional consecutive day off therapy for the longest treatment interruption (OR = 1.34; 95%CI [1.15, 1.68], P<0.0001) and each additional treatment interruption for more than 2 days (OR = 1.38; 95%CI [1.13, 1.77], P<0.002) increased the risk of virologic rebound. In those with low-to-moderate adherence (i.e. <80%), treatment interruption duration (16.2 days versus 6.1 days in the control group, P<0.02), but not average adherence (53.1% vs 55.9%, respectively, P = 0.65) was significantly associated with virologic rebound. Conclusions: Sustained treatment interruption may pose a greater risk of virologic rebound on NNRTI therapy than the same number of interspersed missed doses at low-to-moderate adherence