Uretroplastia bulbar con injerto: una actualización sobre las diferentes técnicas quirúrgicas

En pacientes con estrechez uretral bulbar de una longitud mayor a 2 cm, que no sean candidatos a otras técnicas, se realiza uretroplastia con injerto. Actualmente se emplean diversas técnicas, cada una con ventajas y desventajas propias. Describir las ventajas y desventajas de las técnicas quirúrgicas empleadas actualmente en la uretroplastia con injerto, así como sus tasas de éxito. Se hizo una búsqueda en PubMed, ClinicalKey y en ScienceDirect, utilizando las palabras claves: “urethral stricture,” “urethroplasty,” “oral graft” y “flap.” Se utilizaron los estudios más relevantes, tanto originales como revisiones sistemáticas y meta-análisis, en inglés y en español. Las diferentes técnicas quirúrgicas ofrecen ventajas y desventajas teóricas frente a las otras, aunque las tasas de éxito en todas es cercana al 90%, sin ser una francamente superior frente a las demás. La elección de la técnica quirúrgica a realizar depende de las preferencias y experiencia del cirujano, dado que la tasa de éxito para todas las técnicas es similar.In patients with urethral stricture longer than 2 cm who are not candidates for other techniques, graft urethroplasty is the most performed surgery. Currently, several techniques are used, each with their own advantages and disadvantages. Describe the advantages and disadvantages of the surgical techniques currently used in graft urethroplasty, as well as their success rates. A search was made in PubMed, ClinicalKey and ScienceDirect, using the keywords: “urethral stenosis,” “urethroplasty,” “oral graft” and “flap.” The most relevant original studies, systematic reviews and meta-analyzes were used, both in English and Spanish. The different surgical techniques offer theoretical advantages compared with the others, although the success rates in all are close to 90%, without being frankly superior compared with the others. The choice of the surgical technique to be performed depends on the preferences and experience of the surgeon, given that the success rate for all techniques is similar

Sonochemical degradation of antibiotics from representative classes-Considerations on structural effects, initial transformation products, antimicrobial activity and matrix

In this work, the sonochemical treatment (at 354 kHz and 88 W L-120 ) of six relevant antibiotics belonging to fluoroquinolones (ciprofloxacin and norfloxacin), penicillins (oxacillin and cloxacillin) and cephalosporins (cephalexin and cephadroxyl) classes was evaluated. Firstly, the ability of the process to eliminate them was tested, showing that sonodegradation of these antibiotics is strongly chemical structure25 dependent. Thus, correlations among initial degradation rate of pollutants (Rd), solubility in water (Sw), water-octanol partition coefficient (Log P) and topological polar surface area (TPSA) were tested. Rd exhibited a good correlation with Log P (i.e., the hydrophobicity degree of antibiotics). The considered penicillins had the fastest elimination and from the constitutional analysis using Lemke method was clear that the functional groups arrangement on these antibiotics made them highly hydrophobics. The penicillins were degraded closer at cavitation bubble than the fluoroquinolones or cephalosporins. The investigation of degradation products showed that sonogenerated hydroxyl radical primary attacked the β-lactam ring of cloxacillin and cephalexin, whereas on norfloxacin induced a decarboxylation. On the other hand, the evolution of antimicrobial activity was also followed. It was evidenced the process capacity to remove antimicrobial activity from treated solutions, which was associated to the transformations of functional groups on antibiotics with important role for interaction with bacteria. Additionally, degradation of antibiotics having the highest (the most hydrophobic, i.e., cloxacillin) and lowest (the most hydrophilic, i.e., cephadroxyl) Rd, was performed in synthetic matrices (hospital wastewater and seawater). Ultrasound degraded both antibiotics; for cloxacillin in such waters higher eliminations than in distilled water were observed (probably due to a salting-out effect exerted by matrix components). Meanwhile, for cephadroxyl a moderate inhibition of degradation in hospital wastewater and seawater respect to distilled water was found, this was related to competition by hydroxyl radical of the other substances in the matrices. These results show the quite selectivity of high frequency ultrasound to eliminate antibiotics form different classes even in complex matrices

Caracterización e inmovilización de pectinasa comercial

A través de los avances de la biotecnología se han estudiado las enzimas, las cuales pueden acelerar procesos químicos generando así ahorro de tiempo, dinero y esfuerzo a nivel productivo. En el presente trabajo, se caracterizó una pectinasa comercial y a su vez se evaluó la encapsulación por atrapamiento en alginato. El método de inmovilización por alginato de sodio al 2% donde se atrapó la enzima en pequeñas cápsulas; para evaluar la variación de azúcares reductores por método DNS que es un indicador del rompimiento de los enlaces glucosídicos, lo cual es fundamental en la clarificación de jugos o vinos. La inmovilización por medio de alginato de sodio generó un aumento en los azúcares reductores de la matriz alimentaria. Estos resultados permiten la utilización y la incorporación de la enzima a diversos procesos e industrias como la de clarificación

G protein-coupled estrogen receptor activation by bisphenol-A disrupts the protection from apoptosis conferred by the estrogen receptors ERα and ERβ in pancreatic beta cells

17β-estradiol protects pancreatic β-cells from apoptosis via the estrogen receptors ERα, ERβ and GPER. Conversely, the endocrine disruptor bisphenol-A (BPA), which exerts multiple effects in this cell type via the same estrogen receptors, increased basal apoptosis. The molecular-initiated events that trigger these opposite actions have yet to be identified. We demonstrated that combined genetic downregulation and pharmacological blockade of each estrogen receptor increased apoptosis to a different extent. The increase in apoptosis induced by BPA was diminished by the pharmacological blockade or the genetic silencing of GPER, and it was partially reproduced by the GPER agonist G1. BPA and G1-induced apoptosis were abolished upon pharmacological inhibition, silencing of ERα and ERβ, or in dispersed islet cells from ERβ knockout (BERKO) mice. However, the ERα and ERβ agonists PPT and DPN, respectively, had no effect on beta cell viability. To exert their biological actions, ERα and ERβ form homodimers and heterodimers. Molecular dynamics simulations together with proximity ligand assays and coimmunoprecipitation experiments indicated that the interaction of BPA with ERα and ERβ as well as GPER activation by G1 decreased ERαβ heterodimers. We propose that ERαβ heterodimers play an antiapoptotic role in beta cells and that BPA- and G1-induced decreases in ERαβ heterodimers lead to beta cell apoptosis. Unveiling how different estrogenic chemicals affect the crosstalk among estrogen receptors should help to identify diabetogenic endocrine disruptors.This work was supported by Ministerio de Ciencia e Innovación, Agencia Estatal de Investigación (AEI) and Fondo Europeo de Desarrollo Regional (FEDER) grants BPU2017-86579-R (AN), PID2020-117294RB-I00 (AN, JM-P), Generalitat Valenciana PROMETEO II/2020/006 (AN) and European Union’s Horizon 2020 research and innovation programme under grant agreement GOLIATH No. 825489 (AN). Author laboratories hold grants from Ministerio de Ciencia e Innovación, Agencia Estatal de Investigación y Fondo Europeo de Desarrollo Regional (FEDER) RTI2018-096724-B-C21 (J-AE) and PID2020-117569RA-I00 (LM). PROMETEO/2016/006 (J-AE) and SEJI/2018/023 (LM) supported by Generalitat Valenciana, Spain. Robert A. Welch Foundation (grant E-0004) (J-AG). CIBERDEM is an initiative of the Instituto de Salud Carlos III

Evaluación de melaza como medio de cultivo para la producción de bacterias ácido-lácticas

Bioprocesses are those processes that involve the manipulation of living organisms or their cellular components as substrates in order to obtain a biomass or product to provide goods or services as an example, the use of bacteria acid lactic acid in biopreservacion, this was proposed as target bacteria produce acid lactic acid in an aerobic bioreactor through a conventional molasses as carbon source and check the development of the micro-organism as biomass, to accomplish this was carried out in two different twinjet with volumes of 7, 5L, 0, 5 L using the same substrate and inoculum I, evaluating chemical variables such as pH, acidity, ºbrix, reducing sugars and absorbance . The results show a correct development of the bacteria metabolism lactic acid observing one acidification of the environment demonstrating in the pH decrease and increase of titrable acidity, also seeing a decrease in sugars reducers interpreting this as the consumption of the carbon of the micro-organism and the realization of a process source fermentation and verifying the biomass growth through units of absorbance and the weight of the produced biomass, and may conclude that there was a proper acid development of bacteria lactic demonstrating that molasses is a source of carbon and a half of crop suitable for the production of this bacterium.Los bioprocesos son aquellos procesos que involucran la manipulación de organismos vivos o sus componentes celulares como sustratos, con el fin de obtener una biomasa o producto para proveer bienes o servicios, por ejemplo, el uso de bacterias ácido lácticas en biopreservación, por esto se propuso como objetivo producir bacterias ácido lácticas en un biorreactor aerobio a través de una fuente de carbono convencional como la melaza y comprobar el desarrollo del microorganismo como biomasa, para realizar esto se realizó en dos diferentes birreactores con volúmenes de 7,5L y 0,5L utilizando el mismo sustrato e inóculo, evaluando variables químicas como lo son el pH, acidez, °Brix, azúcares reductores y absorbancia. Los resultados mostraron un correcto desarrollo del metabolismo de la bacteria ácido láctica observando una acidificación del medio evidenciándose en la disminución del pH y el aumento de la acidez titulable, mostrando también una disminución en los azúcares reductores; interpretando esto, como el consumo de la fuente de carbono del microorganismo y la realización de un proceso fermentativo y verificando un crecimiento de la biomasa a través de las unidades de absorbancia y el peso de la biomasa producida, concluyendo que hubo un correcto desarrollo de la bacteria ácido láctica, demostrando que la melaza es una fuente de carbono y medio de cultivo apto para la producción de esta bacteria

Evaluación del efecto de la concentración de sustrato como fuente de nitrógeno y el inóculo en la producción de pleurotus ostreatus

Uno de los hongos comestibles más estudiado y cultivado durante los últimos años es el Pleurotus ostreatus debido a la facilidad de cultivo y a su calidad nutricional. El objetivo de este trabajo fue evaluar crecimiento y la producción Pleurotus ostreatus con el fin de establecer las condiciones óptimas respecto al inóculo y sustrato, para esto se utilizó la metodología de superficie de respuesta para evaluar los efectos del porcentaje de inóculo variándolo entre el 3 y 9%, y porcentaje de la fuente de nitrógeno variándolo entre el 20 y 40%, se prepararon 11 tratamientos para realizar las corridas del diseño experimental, como fuente de nitrógeno se utilizó salvado de trigo, como fuente de carbono se utilizó aserrín, los tratamientos fueron incubados en una cámara climática a 28°C y 65% de humedad por 46 días. Después del periodo de incubación se observó el crecimiento micelial en las bolsas de cada tratamiento este se calificó de 1 a 5 siendo 1 el de menor crecimiento y 5 el de mayor. Los tratamientos con mayor crecimiento de micelio en los sustratos fueron los que tenían una composición de 30% de fuente de nitrógeno y un 6% de inóculo. En la superficie de respuesta se observó que el porcentaje óptimo de inóculo esta alrededor del 5% y el de fuente de nitrógeno alrededor del 25%. Para un cultivo adecuado del Pleurotus o, se deben manejar adecuadamente las condiciones de temperatura, humedad y luz y un manejo aséptico para evitar el crecimiento de otros organismos que compitan por el sustrato

An Auristatin nanoconjugate targeting CXCR4+ leukemic cells blocks acute myeloid leukemia dissemination

Altres ajuts: EU COST Action CA 17140 to R.M. A grant from La Generalitat de Catalunya (PERIS) [SLT002/16/00433 to J.S.]; a grant from the Generalitat de Catalunya CERCA Programme. The work was also supported by PERIS program from the health department of the Generalitat de Catalunya (SLT006/17/00093) [grated to U.U.] and Fundación Española de Hematología y Hemoterapia (FEHH) [granted to V.P.]. Finally, AV received an ICREA ACADEMIA Award supported by the Catalan Government.Background: current acute myeloid leukemia (AML) therapy fails to eliminate quiescent leukemic blasts in the bone marrow, leading to about 50% of patient relapse by increasing AML burden in the bone marrow, blood, and extramedullar sites. We developed a protein-based nanoparticle conjugated to the potent antimitotic agent Auristatin E that selectively targets AML blasts because of their CXCR4 receptor overexpression (CXCR4+) as compared to normal cells. The therapeutic rationale is based on the involvement of CXCR4 overexpression in leukemic blast homing and quiescence in the bone marrow, and the association of these leukemic stem cells with minimal residual disease, dissemination, chemotherapy resistance, and lower patient survival. - Methods: monomethyl Auristatin E (MMAE) was conjugated with the CXCR4 targeted protein nanoparticle T22-GFP-H6 produced in E. coli. Nanoconjugate internalization and in vitro cell viability assays were performed in CXCR4+ AML cell lines to analyze the specific antineoplastic activity through the CXCR4 receptor. In addition, a disseminated AML animal model was used to evaluate the anticancer effect of T22-GFP-H6-Auristatin in immunosuppressed NSG mice (n = 10/group). U of Mann-Whitney test was used to consider if differences were significant between groups. - Results: T22-GFP-H6-Auristatin was capable to internalize and exert antineoplastic effects through the CXCR4 receptor in THP-1 and SKM-1 CXCR4+ AML cell lines. In addition, repeated administration of the T22-GFP-H6-Auristatin nanoconjugate (9 doses daily) achieves a potent antineoplastic activity by internalizing specifically in the leukemic cells (luminescent THP-1) to selectively eliminate them. This leads to reduced involvement of leukemic cells in the bone marrow, peripheral blood, liver, and spleen, while avoiding toxicity in normal tissues in a luminescent disseminated AML mouse model. - Conclusions: a novel nanoconjugate for targeted drug delivery of Auristatin reduces significantly the acute myeloid leukemic cell burden in the bone marrow and blood and blocks its dissemination to extramedullar organs in a CXCR4+ AML model. This selective drug delivery approach validates CXCR4+ AML cells as a target for clinical therapy, not only promising to improve the control of leukemic dissemination but also dramatically reducing the severe toxicity of classical AML therapy

Fluorescent dye labeling changes the biodistribution of cell-targeted nanoparticles

Fluorescent dye labeling is a common strategy to analyze the fate of administered nanoparticles in living organisms. However, to which extent the labeling processes can alter the original nanoparticle biodistribution has been so far neglected. In this work, two widely used fluorescent dye molecules, namely, ATTO488 (ATTO) and Sulfo-Cy5 (S-Cy5), have been covalently attached to a well-characterized CXCR4-targeted self-assembling protein nanoparticle (known as T22-GFP-H6). The biodistribution of labeled T22-GFP-H6-ATTO and T22-GFP-H6-S-Cy5 nanoparticles has been then compared to that of the non-labeled nanoparticle in different CXCR4+ tumor mouse models. We observed that while parental T22-GFP-H6 nanoparticles accumulated mostly and specifically in CXCR4+ tumor cells, labeled T22-GFP-H6-ATTO and T22-GFP-H6-S-Cy5 nanoparticles showed a dramatic change in the biodistribution pattern, accumulating in non-target organs such as liver or kidney while reducing tumor targeting capacity. Therefore, the use of such labeling molecules should be avoided in target and non-target tissue uptake studies during the design and development of targeted nanoscale drug delivery systems, since their effect over the fate of the nanomaterial can lead to considerable miss-interpretations of the actual nanoparticle biodistribution

Use of Confocal Laser as Light Source Reveals Stomata-Autonomous Function

In most terrestrial plants, stomata open during the day to maximize the update of CO(2) for photosynthesis, but they close at night to minimize water loss. Blue light, among several environmental factors, controls this process. Stomata response to diverse stimuli seems to be dictated by the behaviour of neighbour stomata creating leaf areas of coordinated response. Here individual stomata of Arabidopsis leaves were illuminated with a short blue-light pulse by focusing a confocal argon laser. Beautifully, the illuminated stomata open their pores, whereas their dark-adapted neighbours unexpectedly experience no change. This induction of individual stomata opening by low fluence rates of blue light was disrupted in the phototropin1 phototropin2 (phot1 phot2) double mutant, which exhibits insensitivity of stomatal movements in blue-illuminated epidermal strips. The irradiation of all epidermal cells making direct contact with a given stoma in both wild type and phot1 phot2 plants does not trigger its movement. These results unravel the stoma autonomous function in the blue light response and illuminate the implication of PHOT1 and/or PHOT2 in such response. The micro spatial heterogeneity that solar blue light suffers in partially shaded leaves under natural conditions highlights the physiological significance of the autonomous stomatal behaviour

Socialización escolar : procesos, experiencias y trayectos

En los artículos que forman parte de este libro se despliega un conjunto de temas, problemas y debates que, en un primer momento, se hicieron presentes entre el equipo coordinador del libro y que luego fueron compartidos con los investigadores miembros del Grupo de Trabajo "Juventudes, Infancias: Políticas, Culturas e Instituciones Sociales" (GT) del Consejo Latinoamericano de Ciencias Sociales (CLACSO). En tal sentido, el propósito de la compilación consiste en aportar a la actualización de un área o campo que, desde sus inicios, fue y es pensado por las ciencias sociales: la escuela y los sistemas educativos. Sin embargo, en los últimos años, el campo de estudios sobre la escuela se ha diversificado y especializado, encontrando nuevos objetos de estudio y ampliando los ya existentes, al tiempo que los temas y problemas educativos se hablan y debaten por toda la sociedad