Transcriptional Activation of Antioxidants May Compensate for Selenoprotein Deficiences in \u3ci\u3eAmblyomma maculatum\u3c/i\u3e (Acari: Ixodidae) Injected With \u3ci\u3eselK\u3c/i\u3e- or \u3ci\u3eselM\u3c/i\u3e- dsRNA

The Gulf‐Coast tick, Amblyomma maculatum, possesses an elaborate set of selenoproteins, which prevent the deleterious effects from oxidative stress that would otherwise occur during feeding. In the current work, we examined the role of selenoprotein K (SelK) and selenoprotein M (SelM) in feeding A. maculatum by bioinformatics, transcriptional gene expression, RNA interference and antioxidant assays. The transcriptional expression of SelK did not vary significantly in salivary glands or midguts throughout the bloodmeal. However, there was a 58‐fold increase in transcript levels of SelM in tick midguts. Ticks injected with selK‐dsRNA or selM‐dsRNA did not reveal any observable differences in egg viability but oviposition was reduced. Surprisingly, salivary antioxidant activity was higher in selenoprotein knockouts compared with controls, which is probably the result of compensatory transcriptional expression of genes involved in combating reactive oxygen species. In fact, quantitative real‐time PCR data suggest that the transcriptional expression of catalase increased in ticks injected with selM‐double‐stranded RNA. Additionally, the transcriptional expression of selN decreased ∼90% in both SelK/SelM knockdowns. These data indicate that SelK and SelM are salivary antioxidants but are not essential for tick survival or reproduction and are compensated by other antioxidant systems

Modelización matemática en la formación de futuros profesores: desarrollo de proyectos y prácticas profesionales docentes con modelización

Este trabajo presenta resultados producidos en el marco de una investigación que tiene por objeto caracterizar el desarrollo profesional de futuros profesores de matemática que se involucran en el diseño y ejecución de proyectos de modelización matemática. En particular, analizamos un proyecto de modelización de estudiantes de profesorado en matemática y su huella en la práctica profesional docente posterior de dichos estudiantes. Nos referimos a dificultades, desafíos y obstáculos que tuvieron que enfrentar, tanto durante el desarrollo de sus proyectos de modelización cuanto en la preparación y puesta en marcha de actividades de modelización para el aula. Discutimos aportes de ambas experiencias para el desarrollo profesional de estos estudiantes

Children with grand Imaginaries: Bringing them closer to the world of science

Although at present there are academic strategies for scientific dissemination, it is still a challenge for the general population to access quality information that is reliable, easy to understand and motivational towards science. This article proposes an image-based educational scientific dissemination tool with the goal of bringing children closer to science, through the recognition of relevant characters and their contributions. The study was developed along three stages. The first and second were conducted through a qualitative analytical approach with an interpretative perspective, using a documental method, with a review and analysis technique. During the first stage, a review and selection of studies related to scientific dissemination for children was conducted. The second one focused on the identification and selection of scientific characters, through the establishment of categories and criteria. The third stage relates to the design of outstanding characters’ biographical cards. The main contribution of this proposal is the assembly of a semantic network to portray a completed character profile, time context, place of origin, contributions, impacts, acknowledgements or prizes, as well as limitations or difficulties in context. Therefore, a mean of disclosure was devised through cards with a highly graphic and animated content regarding scientific characters sized in a gaming strategy called ‘Sapiencia’, a ludic and motivational learning tool

EFECTO DEL CONSUMO DE ALCOHOL ETÍLICO SOBRE LA ACTIVIDAD SEXUAL DE RATONES MACHOS

In this article, the effect of ethanol ingestion on sexual activity in male mice was determined. Three groups of five mice were exposed to the consumption of ethanol at different concentrations (5, 10 and 20%) for one hour. Subsequently, each mouse was transferred to a glass box together with a female, where sexual activity was observed. The frequencies of patterns for each sexual activity were recorded for periods of 5 minutes, until completing 45 minutes of observations. Nine activities grouped into two phases were identified during the sexual act: recognition and copulation. The recognition phase included female grooming, genital smell, persecution, presentation, body olfactory and evasion. For its part, the copulation phase made up of: attempt to mount, mount and intromission. Statistical differences between treatments were determined, which indicated that ethanol affects the frequency of each sexual activity analyzed. Besides, significant associations were identified between sexual activities and the concentrations provided. During the recognition phase, ethanol had both enhancing and suppressive effects. The activities that constitute the copulation phase showed a considerable decrease in ethanol treatments, indicating a suppressive effect.Se determinó el efecto de la ingesta de etanol sobre la actividad sexual en ratones machos. Tres grupos de cinco ratones fueron expuestos al consumo de etanol a concentraciones de 5, 10 y 20% durante una hora. Posteriormente, se transfirió cada ratón a una caja de vidrio junto a una hembra, donde se observó la actividad sexual. Se registró las frecuencias de patrones para cada actividad sexual por periodos de 5 minutos, hasta completar 45 minutos de observaciones. Durante el acto sexual, se identificaron nueve actividades agrupadas en dos fases: reconocimiento y cópula. La fase de reconocimiento comprendió el acicalamiento a la hembra, la olfacción genital, persecución, presentación, olfacción corporal y evasión. La fase de cópula estuvo conformada por las siguientes actividades: intento de monta, monta e intromisión. Hubo diferencias estadísticas entre los tratamientos, lo que sugiere que el etanol tiene un efecto sobre la frecuencia de cada actividad sexual analizada. Adicionalmente, se determinó asociaciones significativas entre las actividades sexuales y las concentraciones suministradas. Durante la fase de reconocimiento, el etanol impulsó tanto efectos potenciadores como supresores. Las actividades que constituyen la fase de cópula mostraron una disminución considerable sobre los tratamientos de etanol, indicando un efecto supresor

Diabetes induced by gain-of-function mutations in the Kir6.1 subunit of the KATP channel

Gain-of-function (GOF) mutations in the pore-forming (Kir6.2) and regulatory (SUR1) subunits of K(ATP) channels have been identified as the most common cause of human neonatal diabetes mellitus. The critical effect of these mutations is confirmed in mice expressing Kir6.2-GOF mutations in pancreatic β cells. A second K(ATP) channel pore-forming subunit, Kir6.1, was originally cloned from the pancreas. Although the prominence of this subunit in the vascular system is well documented, a potential role in pancreatic β cells has not been considered. Here, we show that mice expressing Kir6.1-GOF mutations (Kir6.1[G343D] or Kir6.1[G343D,Q53R]) in pancreatic β cells (under rat-insulin-promoter [Rip] control) develop glucose intolerance and diabetes caused by reduced insulin secretion. We also generated transgenic mice in which a bacterial artificial chromosome (BAC) containing Kir6.1[G343D] is incorporated such that the transgene is only expressed in tissues where Kir6.1 is normally present. Strikingly, BAC-Kir6.1[G343D] mice also show impaired glucose tolerance, as well as reduced glucose- and sulfonylurea-dependent insulin secretion. However, the response to K(+) depolarization is intact in Kir6.1-GOF mice compared with control islets. The presence of native Kir6.1 transcripts was demonstrated in both human and wild-type mouse islets using quantitative real-time PCR. Together, these results implicate the incorporation of native Kir6.1 subunits into pancreatic K(ATP) channels and a contributory role for these subunits in the control of insulin secretion

Children with grand Imaginaries: Bringing them closer to the world of science

Although at present there are academic strategies for scientific dissemination, it is still a challenge for the general population to access quality information that is reliable, easy to understand and motivational towards science. This article proposes an image-based educational scientific dissemination tool with the goal of bringing children closer to science, through the recognition of relevant characters and their contributions. The study was developed along three stages. The first and second were conducted through a qualitative analytical approach with an interpretative perspective, using a documental method, with a review and analysis technique. During the first stage, a review and selection of studies related to scientific dissemination for children was conducted. The second one focused on the identification and selection of scientific characters, through the establishment of categories and criteria. The third stage relates to the design of outstanding characters’ biographical cards. The main contribution of this proposal is the assembly of a semantic network to portray a completed character profile, time context, place of origin, contributions, impacts, acknowledgements or prizes, as well as limitations or difficulties in context. Therefore, a mean of disclosure was devised through cards with a highly graphic and animated content regarding scientific characters sized in a gaming strategy called ‘Sapiencia’, a ludic and motivational learning tool

Nitrogen fixation and transfer in open ocean diatom–cyanobacterial symbioses

Many diatoms that inhabit low-nutrient waters of the open ocean live in close association with cyanobacteria. Some of these associations are believed to be mutualistic, where N2-fixing cyanobacterial symbionts provide N for the diatoms. Rates of N2 fixation by symbiotic cyanobacteria and the N transfer to their diatom partners were measured using a high-resolution nanometer scale secondary ion mass spectrometry approach in natural populations. Cell-specific rates of N2 fixation (1.15–71.5 fmol N per cell h−1) were similar amongst the symbioses and rapid transfer (within 30 min) of fixed N was also measured. Similar growth rates for the diatoms and their symbionts were determined and the symbiotic growth rates were higher than those estimated for free-living cells. The N2 fixation rates estimated for Richelia and Calothrix symbionts were 171–420 times higher when the cells were symbiotic compared with the rates estimated for the cells living freely. When combined, the latter two results suggest that the diatom partners influence the growth and metabolism of their cyanobacterial symbionts. We estimated that Richelia fix 81–744% more N than needed for their own growth and up to 97.3% of the fixed N is transferred to the diatom partners. This study provides new information on the mechanisms controlling N input into the open ocean by symbiotic microorganisms, which are widespread and important for oceanic primary production. Further, this is the first demonstration of N transfer from an N2 fixer to a unicellular partner. These symbioses are important models for molecular regulation and nutrient exchange in symbiotic systems