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Parabens (PBs) are widely used in the cosmetic, pharmaceutical, and food industries as preservatives of products. Because of its great use, humans and other organisms are highly exposed daily. However, little is known about the effect of PBs on male infertility. Therefore, the aim of the present study was to evaluate the effect of methylparaben (MePB) and propylparaben (PrPB), alone or in combination, on the physiological characteristics of pig in vitro exposed sperm to different concentrations (0, 200, 500, and 700 µM) for viability, motility, and acrosome integrity evaluation and (0, 200, 500, 700, 1000, and 2000 µM) for DNA fragmentation index evaluation, after 4 h of exposure. The results showed that sperm viability decreased after exposure to MePB from the concentration of 500 µM. In the PrPB and mixture groups, viability decreased at all concentrations except for the control. The decrease in viability of sperm exposed to PrPB was greater than that of the mixture and MePB groups. Sperm motility decreased in all the experimental groups exposed to PBs, at all concentrations, except for the control group. Acrosome integrity was not decreased in the MePB group; however, in the PrPB group, it decreased at a concentration of 200 µM and in the mixture at 500 µM. All groups exhibited DNA damage at different concentrations, except for the control group. Additionally, the effect of PBs on sperm quality was concentration-dependent. The results demonstrated that MePB and PrPB alone or in combination can have adverse effects on sperm quality parameters. MePB had lower toxicity than did both PrPB and the mixture. The mixture did not have an additive effect on any of the parameters evaluated. This could partially explain the link between PB exposure and infertility.

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Early-onset scoliosis corresponds to a group of heterogeneous spinal conditions that present before 10 years of age with a curvature in the coronal plane of 10° or more. Regardless of the etiology, adequate control of the deformity is required to avoid cardiopulmonary deterioration and preserve quality and life expectancy. Diagnosis can be difficult and is usually incidental at a young age. To choose the best treatment, it is important to consider the patient's age, etiology, and rate of progression. Among the non-operative treatments, the most effective are the use of serial casts or brace, whose main objective is to stop the progression of the deformity and thus delay surgical treatment. Among the surgical treatments the distraction based systems and definitive arthrodesis have proven to be most effective. Early surgery leads to multiple complications, which is why, if feasible, non surgical management should be sought and fusion postponed till skeletal maturity. Due to the life-threatening risks associated with the deformity and treatment, it is important to educate the patient and family members about the importance of treatment adherence and follow-up.

La escoliosis de inicio temprano corresponde a un grupo heterogéneo de padecimientos de la columna, la cual se presenta antes de los 10 años de edad con una curvatura en el plano coronal de 10° o más. Independientemente de la etiología requiere un adecuado control de la deformidad para evitar deterioro cardiopulmonar, disminución en la calidad y expectativa de vida. El diagnóstico puede ser difícil y habitualmente se da de forma incidental. Para el tratamiento, es importante considerar la edad del paciente, la etiología y la velocidad de progresión. Dentro de los tratamientos conservadores, se encuentra el uso de yesos seriados o el corsé, cuyo objetivo principal es detener la progresión de la deformidad y con ello retrasar la cirugía a una edad mayor. Dentro de los tratamientos quirúrgicos se encuentran el uso de barras de crecimiento tradicionales, las barras de crecimiento magnéticas y la artrodesis definitiva. Se ha observado que realizarlos de forma temprana condiciona múltiples complicaciones por lo cual, de ser posible, debe optarse por el manejo no quirúrgico y postergar el tratamiento definitivo. Debido a los riesgos potencialmente mortales que conlleva la deformidad y el tratamiento, es de importancia educar al paciente y sus familiares sobre la importancia del apego y el seguimiento.

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Dendroctonus-bark beetles are natural components and key ecological agents of coniferous forests. They spend most of their lives under the bark, where they are exposed to highly toxic terpenes present in the oleoresin. Cytochrome P450 (CYP) is a multigene family involved in the detoxification of these compounds. It has been demonstrated that CYP6DE and CYP6DJ subfamilies hydroxylate monoterpenes, whose derivatives can act as pheromone synergist compounds or be pheromones themselves in these insects. Given the diversity and functional role of CYPs, we investigated whether these cytochromes have retained their function throughout the evolution of these insects. To test this hypothesis, we performed a Bayesian phylogenetic analysis to determine phylogenetic subgroups of cytochromes in these subfamilies. Subgroups were mapped and reconciled with the Dendroctonus phylogeny. Molecular docking analyses were performed with the cytochromes of each subgroup and enantiomers of α-pinene and ß-pinene, (+)-3-carene, ß-myrcene and R-(+)-limonene. In addition, functional divergence analysis was performed to identify critical amino acid sites that influence changes in catalytic site conformation and/or protein folding. Three and two phylogenetic subgroups were recovered for the CYP6DE and CYP6DJ subfamilies, respectively. Mapping and reconciliation analysis showed different gain and loss patterns for cytochromes of each subgroup. Functional predictions indicated that the cytochromes analyzed are able to hydroxylate all monoterpenes; however, they showed preferential affinities to different monoterpenes. Functional divergence analyses indicated that the CYP6DE subfamily has experimented type I and II divergence, whereas the CYP6DJ subfamily has evolved under strong functional constraints. Results suggest cytochromes of the CYP6DE subfamily evolve to reinforce their detoxifying capacity hydroxylating mainly α- and ß-pinene to (+) and (-)-trans-verbenol, being the negative enantiomer used as a pheromone by several Dendroctonus species; whereas cytochromes of the CYP6DJ subfamily appear to retain their original function related to the detoxification of these compounds.

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Objective: To evaluate the knowledge, attitudes and behavior regarding antibiotics, use of antibiotics, and antibiotic resistance in students and health care professionals of the district of Barranquilla, Colombia. Study design: Descriptive, cross-sectional. Methods: A sample of 399 respondents was selected, that included health professionals and medical students from 12 health institutions in the district of Barranquilla (Colombia), using an established stratified sampling method. Each of the respondent professionals completed a survey that included 43 items in the Likert scale. A descriptive analysis of the study variables was performed using the software SPSS version 25. Results: Most of the respondents were women (64.4%), aged between 26 and 35 years (47.6%); 28.8% were nurses and 26.1% general practitioners, with ≤10 years of professional experience (63.4%). Overall, the survey revealed that the participants had considerable knowledge about antibiotic use (89.5%-98% correct answers) and the spread of antibiotic resistance (67.4%-89% correct answers). Approximately 74% of the respondents agreed or fully agreed with the questions related to the management of infections and the provision of advice. Conclusions: The present study revealed that most of the health care professionals surveyed had a good knowledge about antibiotic use, although strategies must be developed to strengthen knowledge regarding the spread of antibiotic resistance. Likewise, it is important to identify opportunities for improvement related with access to the guidelines and/or materials necessary to treat infections and to provide advice on antibiotic use and antibiotic resistance.

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No Abstract available.

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The COVID-19 pandemic has changed in a significant way the lifestyle in the world and in Mexico. Medicine is not an exception, therefore, modifications in how the assessment and treatment of our patients is done, is mandatory to assure the safeness of the patient, the medical team, the hospital staff, the medical facility, and the community. In this paper, the Mexican Association of Spine Surgery (AMCICO) make recommendations based in the information available at the moment, to help decide when and how to perform a spine surgery in the coronavirus pandemic. Objective: To provide the spine surgeon with the tools required and a decision path to postpone or perform a spine surgery in the COVID-19 pandemic.

La pandemia de COVID-19 ha afectado de forma significativa la forma de vida en el mundo y en México. El área de la medicina no es la excepción, ya que se requiere hacer cambios en la forma en la que valoramos y tratamos a nuestros pacientes para tratar de garantizar su seguridad, la del equipo médico y el personal de salud, las instituciones de salud y la comunidad. En este artículo exponemos las recomendaciones de la Asociación Mexicana de Cirujanos de Columna (AMCICO) para realizar una cirugía de columna durante la pandemia del nuevo coronavirus COVID-19. Objetivo: Proveer al cirujano de columna los elementos necesarios para seguir una ruta en la toma de decisiones para posponer o realizar una cirugía de columna durante la pandemia del nuevo coronavirus COVID-19.

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The wastewater from gold exploitation is well known for the toxic nature of recalcitrant cyanide metallic complexes. In this work the selectivity in the photocatalytic degradation of gold mining wastewater (Fe(CN)63-) using suspended TiO2 with alcoholic and organic acid scavengers in a mini-CPC photoreactor with a 30 W UV-A LED as an artificial source of light was evaluated. The study was done in four stages: 1. load catalyst determination, 2. combination of scavengers in a typical photocatalytic degradation, 3. evaluation of scavenger concentration and 4. kinetic study. The decomposition into CN- and Fe removal of the cyanocomplex were tracked. It was observed that formic acid (FA) and t-butanol (t-ButOH) were the best scavengers for the photocatalytic degradation under anoxic conditions. The best concentrations of acceptors used in the study were 10 mM FA and 10 mM t-ButOH at 20 W m-2 of UV-A power, reaching 80% degradation of Fe(CN)63-, 40% Fe removal and 18 ppm of free cyanide CN release to the liquid phase. The electrical efficiency of oxidation per order (EEo) was increased by about 50% with the addition of scavengers instead of traditional anoxic photocatalytic treatment. It was proved that the photocatalytic decomposition of the Fe cyanocomplex was done through the photoreduction path of the metal complex.

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A list of echinoderms from El Salvador (tropical eastern Pacific) is presented. The results were obtained from field surveys (between the years 2000 and 2004), the scarce literature sources, and Internet information. A total of 37 species and six genera are reported. The most abundant echinoderms in rocky shores were: Phataria unifascialis, Echinometra vanbrunti, Holothuria kefersteini, as well as Astropecten armatus in soft bottoms.

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To examine how the time course of rapid events of adaptation affect motion vision, the lower threshold of motion (LTM) was measured for suprathreshold sinusoidal gratings in presence of transient and steady glare. In the case of the transient condition, glare and stimulus were presented separated in time by a variable extent (SOA: 50-450 ms). A two alternative forced choice paradigm using the method of constant stimuli was adopted to measure the LTM. It was found that LTM follows the characteristic Crawford's time course of adaptation. Results are similar for two stimulus duration (300 and 500 ms). It was proposed that the increment of contrast threshold for displacing gratings (C(tq)) due to the loss of sensitivity produced by the sudden onset of the glare source can explain the results.

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