Silico identification, molecular characterization and expression analysis of the Trypanosoma brucei paraflagellar rod protein PFR3

En el presente artículo se describen la identificación y el aislamiento del gen codificante para la proteínaPFR3 del T. brucei. La secuencia deducida de aminoácidos produce una proteína de 592 residuos conun punto isoeléctrico de 5,14 y presenta una identidad de secuencia del 68,9% con la proteína PFR3 delT. cruzi. Sin embargo, el porcentaje de homología entre la proteína PFR3 de T. brucei y otras secuenciasdisponibles de PFRs de T. brucei y T. cruzi es inferior al 22%. En contraste con lo descrito para losmiembros de la familia de proteínas de filamento paraflagelar, la mayor divergencia entre las proteínasPFR3 de T. cruzi y T. brucei se encuentra en la región central de la proteína, con una similitud del 38%en 200 aminoácidos. Estimamos que existen dos copias de la proteína PFR3 de T. brucei por genomahaploide. El gen se transcribe como mARN de aproximadamente 3,6 kb de longitud, presente con lamisma abundancia en formas parasitarias procíclicas y del torrente sanguíneo.In the present paper we describe the identification and isolation of the gene coding for T. brucei PFR3protein. The deduced amino acid sequence produces a protein of 592 residues with an isoelectric pointof 5.14 and shows a 68.9% sequence identity with T. cruzi PFR3 protein. However, the percentage ofhomology among T. brucei PFR3 and other available PFRs sequences from T. brucei and T. cruzi islower than 22%. In contrast to that described for members of paraflagellar rod protein family, thehighest divergence between T. cruzi and T. brucei PFR3 proteins is located at the central region of theprotein with a 38% of similarity over 200 amino acid. We estimate that there exist two copies of theT. brucei PFR3 protein per haploid genome. The gene is transcribed as a mRNA of approximately 3.6kb in length, equally abundant in both procyclic and bloodstream parasite forms

Aerococcus urinae: a rare pathogen in urinary tract infections, associated with patients with underlying urinary pathology

Introducción: Aerococcus urinae es un patógeno urinario poco frecuente que ha sido asociado en la bibliografía a pacientes en la tercera edad, con patología urinaria subyacente. La mala identificación mediante pruebas bioquímicas convencionales, su baja tasa de aislamiento y la similar morfología con otros microorganismos considerados como flora normal en el tracto urinario, hacen de este microorganismo un gran desconocido. El objetivo de este trabajo fue determinar la implicación clínica de Aerococcus urinae en pacientes con infección urinaria, estudiando la relación existente descrita en la bibliografía con pacientes en la tercera edad, con patología urinaria subyacente. Asimismo, debido a su infradiagnóstico en infección urinaria (ITU), se evaluó la utilidad de la espectrometría de masas MALDI-TOF (Bruker) como modelo diagnóstico confiable en el laboratorio de microbiología. Material y métodos: Se realizó un estudio prospectivo en pacientes con infección urinaria desde mayo a septiembre de 2014. Se estudiaron los perfiles de sensibilidad a los antimicrobianos frecuentemente utilizados en infección urinaria. Se registraron los datos clínicos más importantes de los pacientes con un recuento positivo para A. urinae. Resultados: De las 9261 muestras de orina analizadas, 1513 muestras resultaron tener un recuento mayor a 100.000 UFC/mL. A. urinae fue aislado en 3 casos, y la identificación por MALDI-TOF fue fiable a nivel de género y especie ( score ≥ 2) , siendo contrastada mediante secuenciación ARNr 16S. Todos los pacientes que desarrollaron infección urinaria por A. urinae, fueron pacientes en la tercera edad con una patología subyacente, siendo en todos los casos este microorganismo resistente a trimetropim/sulfametoxazol. Conclusiones: La implicación de A. urinae como patógeno urinario, en pacientes con patología urinaria de base, la dificultad en su diagnóstico, y la alta tasa de resistencia de este microorganismo a trimetropim/sulfametoxazol, hacen recomendable establecer una especial atención en los métodos diagnósticos utilizados.Introduction: Aerococcus urinae is an uncommon urinary tract pathogen that has been associated in the literature for older patients with underlying urinary pathology. Misidentification by conventional biochemical tests, their low rate of isolation and similar morphology to other microorganisms considered as normal flora in the urinary tract, makes this organism a great unknown. The aim of this investigation is to determine the implication of Aerococcus urinae as the cause of urinary tract infections, studying the relationship described in literature in elderly patients with underlying urinary pathology. Material and methods: A prospective study on patients with urinary infection, from May to September 2014 was performed. Urine-cultures with a significant bacteria and suspicious of A. urinae, were identified by means of MALDI-TOF system, and contrasted with ARNr 16S sequencing. Profiles of antimicrobial susceptibility frequently used in urinary tract infection were studied. Clinical data for patients with positive urine cultures for A. urinae were registered. Result: 9261 urine samples were analyzed, 1513 samples had counts greater than 100,000 CFU / mL. A. urinae was isolated in 3 cases, and identification by MALDI-TOF was reliable genus and species level (score ≥ 2), being proven by sequencing 16S rRNA. All patients who developed urinary infection by A. urinae were elderly patients with underlying pathology, and this microorganism resistant to trimethoprim / sulfamethoxazole. Conclusions: The A. urinae overt implication as urinary pathogen, the high rate of resistance of this organism to trimethoprim / sulfamethoxazole, and its difficulty to diagnose, urge to pay special attention to the diagnostic methods applied

Elementos móviles: ¿Ventaja evolutiva o parasitismo molecular?

Las secuencias de ADN repetidas–dispersas constituyen una elevada proporción del genoma de organismos eucariotasy procariotas. La primera descripción de movilidad de estas secuencias fue realizada por Barbara McClintock enlos años 50, la cual, estudiando la herencia del color y distribución de la pigmentación del maíz, demostró laexistencia de elementos genéticos con capacidad de transponerse. En el presente trabajo se realiza una revisiónde las características moleculares, filogenéticas y funcionales de los elementos móviles, centrada especialmente enlos elementos LINE. El análisis de la presencia de elementos móviles en los organismos hospedadores, muestra queestos evolucionan coincidentemente con el hospedador para evitar o mitigar el efecto deletéreo de su inserción eincluso para proporcionarle beneficio. Actualmente, se está empezando a considerar que estos elementos jueganun importante papel en la evolución de los organismos, probablemente como resultado del desarrollo de unarelación simbiótica con su hospedador

Atom--Molecule Coherence in a Bose-Einstein Condensate

Coherent coupling between atoms and molecules in a Bose-Einstein condensate (BEC) has been observed. Oscillations between atomic and molecular states were excited by sudden changes in the magnetic field near a Feshbach resonance and persisted for many periods of the oscillation. The oscillation frequency was measured over a large range of magnetic fields and is in excellent quantitative agreement with the energy difference between the colliding atom threshold energy and the energy of the bound molecular state. This agreement indicates that we have created a quantum superposition of atoms and diatomic molecules, which are chemically different species.Comment: 7 pages, 6 figure

Immune adjuvant effect of V. cholerae O1 derived Proteoliposome coadministered by intranasal route with Vi polysaccharide from Salmonella Typhi

Proteoliposome derived from Vibrio cholerae O1 (PLc) is a nanoscaled structure obtained by detergent extraction process. Intranasal (i.n) administration of PLc was immunogenic at mucosal and systemic level vs. V. cholerae; however the adjuvant potential of this structure for non-cholera antigens has not been proven yet. The aim of this work was to evaluate the effect of coadministering PLc with the Vi polysaccharide antigen (Poli Vi) of S. Typhi by i.n route. The results showed that Poli Vi coadministered with PLc (PLc+Poli Vi) induce higher IgA response in saliva (p0.05) to that induced in a group of mice immunised by parenteral route with the Cuban anti-typhoid vaccine vax-TyVi®, although this vaccine did not induce mucosal response. In conclusion, this work demonstrates that PLc can be used as mucosal adjuvant to potentiate the immune response against a polysaccharide antigen like Poli Vi

Formation and Propagation of Matter Wave Soliton Trains

Attraction between atoms in a Bose-Einstein-Condensate renders the condensate unstable to collapse. Confinement in an atom trap, however, can stabilize the condensate for a limited number of atoms, as was observed with 7Li, but beyond this number, the condensate collapses. Attractive condensates constrained to one-dimensional motion are predicted to form stable solitons for which the attractive interactions exactly compensate for the wave packet dispersion. Here we report the formation or bright solitons of 7Li atoms created in a quasi-1D optical trap. The solitons are created from a stable Bose-Einstein condensate by magnetically tuning the interactions from repulsive to attractive. We observe a soliton train, containing many solitons. The solitons are set in motion by offsetting the optical potential and are observed to propagate in the potential for many oscillatory cycles without spreading. Repulsive interactions between neighboring solitons are inferred from their motion

Extracellular histones trigger oxidative stress-dependent induction of the NF-kB/CAM pathway via TLR4 in endothelial cells.

Extracellular histones have been reported to aggravate different pathophysiological processes by increasing vascular permeability, coagulopathy, and inflammation. In the present study, we elucidate how extracellular histones (10-100 µg/mL) concentration dependently increase cytosolic reactive oxygen species (ROS) production using human umbilical vein endothelial cells (HUVECs). Furthermore, we identify cyclooxygenase (COX) and NADPH oxidase (NOX) activity as sources of ROS production in extracellular histone-treated HUVEC. This COX/NOX-mediated ROS production is also involved in enhanced NF-kB activity and cell adhesion molecules (VCAM1 and ICAM1) expression in histone-treated HUVEC. Finally, by using different toll-like receptor (TLR) antagonists, we demonstrate the role of TLR4 in CAMs overexpression triggered by extracellular histones in endothelial cells. In conclusion, our data suggest that through TLR4 signaling, extracellular histones increase endothelial cell activation, a mechanism involving increased COX- and NOX-mediated ROS. These findings increase our understanding on how extracellular histones enhance systemic inflammatory responses in diseases in which histone release occurs as part of the pathological processes

Microbial catabolic activities are naturally selected by metabolic energy harvest rate

The fundamental trade-off between yield and rate of energy harvest per unit of substrate has been largely discussed as a main characteristic for microbial established cooperation or competition. In this study, this point is addressed by developing a generalized model that simulates competition between existing and not experimentally reported microbial catabolic activities defined only based on well-known biochemical pathways. No specific microbial physiological adaptations are considered, growth yield is calculated coupled to catabolism energetics and a common maximum biomass-specific catabolism rate (expressed as electron transfer rate) is assumed for all microbial groups. Under this approach, successful microbial metabolisms are predicted in line with experimental observations under the hypothesis of maximum energy harvest rate. Two microbial ecosystems, typically found in wastewater treatment plants, are simulated, namely: (i) the anaerobic fermentation of glucose and (ii) the oxidation and reduction of nitrogen under aerobic autotrophic (nitrification) and anoxic heterotrophic and autotrophic (denitrification) conditions. The experimentally observed cross feeding in glucose fermentation, through multiple intermediate fermentation pathways, towards ultimately methane and carbon dioxide is predicted. Analogously, two-stage nitrification (by ammonium and nitrite oxidizers) is predicted as prevailing over nitrification in one stage. Conversely, denitrification is predicted in one stage (by denitrifiers) as well as anammox (anaerobic ammonium oxidation). The model results suggest that these observations are a direct consequence of the different energy yields per electron transferred at the different steps of the pathways. Overall, our results theoretically support the hypothesis that successful microbial catabolic activities are selected by an overall maximum energy harvest rate