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Adenosine A2A and dopamine D2 receptors in the basal ganglia form heterotetrameric structures that are involved in the regulation of motor activity and neuropsychiatric functions. The present study examines the A2A receptor-mediated modulation of D2 receptor binding in vivo using positron emission tomography (PET) with the D2 antagonist tracer [11C]raclopride. Healthy male Wistar rats (n = 8) were scanned (60 min dynamic scan) with [11C]raclopride at baseline and 7 days later following an acute administration of the A2A agonist CGS21680 (1 mg/kg), using a MicroPET Focus-220 camera. Nondisplaceable binding potential (BPND) values were calculated using a simplified reference tissue model (SRTM), with cerebellum as the reference tissue. SRTM analysis did not show any significant changes in [11C]raclopride BPND (p = 0.102) in striatum after CGS21680 administration compared to the baseline. As CGS21680 strongly affects hemodynamics, we also used arterial blood sampling and a metabolite-corrected plasma input function for compartment modeling using the reversible two-tissue compartment model (2TCM) to obtain the BPND from the k3/k4 ratio and from the striatum/cerebellum volume of distribution ratio (DVR) in a second group of animals. These rats underwent dynamic [11C]raclopride scans after pretreatment with a vehicle (n = 5), a single dose of CGS21680 (1 mg/kg, n = 5), or a single dose of the A2A antagonist KW6002 (1 mg/kg, n = 5). The parent fraction in plasma was significantly higher in the CGS21680-treated group (p = 0.0001) compared to the vehicle-treated group. GCS21680 administration significantly reduced the striatal k3/k4 ratio (p < 0.01), but k3 and k4 estimates may be less reliable. The BPND (DVR-1) decreased from 1.963 ± 0.27 in the vehicle-treated group to 1.53 ± 0.55 (p = 0.080) or 1.961 ± 0.11 (p = 0.993) after the administration of CGS21680 or KW6002, respectively. Our study suggests that the A2A agonist CGS21680, but not the antagonist KW6002, may reduce the D2 receptor availability in the striatum.

El objetivo del estudio fue analizar la prevalencia de malnutrición por exceso (MNE) y los cambios antropométricos asociados a riesgo cardiometabólico en escolares pertenecientes a colegios públicos de una zona centro-sur de Chile. Material y método: La investigación fue de tipo descriptiva de corte transversal en una muestra 884 párvulos y escolares de enseñanza básica y media (472 hombres [53.39%] y 412 mujeres [46.61%]) de la comuna de San Ignacio, región de Ñuble. Los análisis estadísticos incluyeron prevalencia según características sociodemográficas y regresiones segmentadas para los cambios asociados a la edad en variables antropométricas de índice de masa corporal (IMC), perímetro de cintura (PC) y relación cintura estatura (C/E). Los Resultados muestran que la prevalencia de MNE según IMC corresponde al 49,55% del total de la población evaluada, mientras que, el resultado de la regresión segmentada identificó que los cambios por edad para el IMC, PC y relación C/E difieren según sexo y estado nutricional. En Conclusión, la prevalencia de MNE según IMC corresponde al 49,55% del total de la población evaluada, mientras que la relación C/E y PC muestra que 3 de cada 10 escolares presenta riesgo cardiometabólico. Además, encontramos que los cambios antropométricos en el IMC, PC y relación C/E difieren según sexo y estado nutricional, aumentando las diferencias según la edad y entre estudiantes NP y con MNE. Abstract: The Aim of the study was to analyze the prevalence of overweight and the anthropometric changes associated with cardiometabolic risk in schoolchildren belonging to public schools in a south-central area of Chile. Material and method: The research was descriptive, cross-sectional in a sample of 884 preschoolers and primary and secondary school students (472 men [53.39%] and 412 women [46.61%]) from the commune of San Ignacio, Ñuble. Statistical analyzes included prevalence according to sociodemographic characteristics and segmented regressions for changes associated with age in anthropometric variables of body mass index (BMI), waist circumference (WC) and waist-to-height ratio (WHtR). The Results show that the prevalence of overweight according to BMI corresponds to 49.55% of the total population evaluated, while the result of the segmented regression identified that the changes by age for BMI, WC and WHtR differ according to sex and nutritional status. In Conclusion, In Conclusion, the prevalence of overweight according to BMI corresponds to 49.55% of the total population evaluated, while the WHtR and WC ratio shows that 3 out of 10 schoolchildren present cardiometabolic risk. We also found that anthropometric changes in BMI, WC and WHtR differ by sex and nutritional status, increasing the differences by age and between normal weight and overweight students.

El rendimiento físico se ha asociado con diferentes variantes genéticas. El objetivo de este estudio fue determinar la asociación entre características dermatoglíficas y los genotipos ACTN3 y ECA. La muestra la constituyen 82 seleccionados nacionales de diferentes modalidades deportivas de Brasil, Japón y Chile. Los marcadores ACTN3 y ECA se obtuvieron a través de una muestra de saliva y se analizaron mediante el empleo de cadena de la polimerasa en tiempo real a partir del iQ5ThermalCycler, BioRad, mientras que para la configuración dermatoglifica se utilizó un lector de huella digital Verifier® 320 LC 2.0. Estos deportistas fueron clasificados en grupos de acuerdo a la configuración de sus patrones dermatoglíficos (A, L, W, D10 y SQTL) en los siguientes grupos: aeróbicos (n= 27); anaeróbicos (n= 55). En cuanto a la frecuencia de aparición de polimorfismos, para ambos grupos predomina el genotipo RX 48,0% y 49,1% de ACTN3, y DI 68,0% y 41,3% para ECA, en los grupos aeróbico y anaeróbico respectivamente. En el grupo aeróbico se observa una asociación muy alta entre ACTN3 con presilla, verticilo y D10 (r=0,90), en el grupo anaeróbico solo observa asociación alta en presilla (r=0,77), para el gen ECA se observan asociaciones moderadas entre presilla, verticilo y D10 (r=0,45), en el grupo aeróbico. Conclusión: Las características dermatoglíficas pueden estar asociados con la variante alélica del gen ACTN3 (RR) y ECA (DI), para perfiles deportivos de carácter anaeróbico. Abstract. Physical performance has been associated with different genetic variants. The objective of this study was to determine the association between dermatoglyphic characteristics and the ACTN3 and ECA genotypes. The sample is established by 82 national teams from different sports modalities in Brazil, Japan and Chile. The ACTN3 and ECA markers were obtained through a saliva sample and was analyzed using the polymerase chain in real time from the iQ5ThermalCycler, BioRad, while a Verifier® 320 LC fingerprint reader was used for the dermatoglyphic configuration. These athletes were classified into groups according to the configuration of their dermatoglyphic patterns (A, L, W, D10 and SQTL) in the following groups: aerobics (n = 27); anaerobic (n = 55). Regarding the frequency in the appearance of polymorphisms, the RX genotype 48.0% and 49.1% of ACTN3 predominated for both groups and DI 68.0% and 41.3% for ACE, in the aerobic and anaerobic groups respectively. In the aerobic group a very high association is observed between ACTN3 with a clip, verticil and D10 (r = 0.90), in the anaerobic group only a high association was observed in the clip (r = 0.77), for the ACE gene they are observed moderate associations between clip, verticil and D10 (r = 0.45), in the aerobic group. Conclusion: Dermatoglyphic characteristics may be associated with the allelic variant of the ACTN3 (RR) and RCT (DI) gene, for sports profiles of an anaerobic nature.

P-Glycoprotein (P-gp) is an efflux pump located at the blood-brain barrier (BBB) that contributes to the protection of the central nervous system by transporting neurotoxic compounds out of the brain. A decline in P-gp function has been related to the pathogenesis of neurodegenerative diseases. P-gp inducers can increase the P-gp function and are considered as potential candidates for the treatment of such disorders. The P-gp inducer MC111 increased P-gp expression and function in SW480 human colon adenocarcinoma and colo-320 cells, respectively. Our study aims to evaluate the P-gp inducing effect of MC111 in the whole brain in vivo, using the P-gp tracer [F-18]MC225 and positron emission tomography (PET). Eighteen Wistar rats were treated with either vehicle solution, 4.5 mg/kg of MC111 (low-dose group), or 6 mg/kg of MC111 (high-dose group). Animals underwent a 60 min dynamic PET scan with arterial-blood sampling, 24 h after treatment with the inducer. Data were analyzed using the 1-tissue-compartment model and metabolite-corrected plasma as the input function. Model parameters such as the influx constant (K-1) and volume of distribution (V-T) were calculated, which reflect the in vivo P-gp function. P-gp and pregnane xenobiotic receptor (PXR) expression levels of the whole brain were assessed using western blot. The administration of MC111 decreased K-1 and V-T of [F-18]MC225 in the whole brain and all of the selected brain regions. In the high-dose group, whole-brain K-1 was decreased by 34% (K-1-high-dose = 0.20 +/- 0.02 vs K-1-control = 0.30 +/- 0.02; p < 0.001) and in the low-dose group by 7% (K-1-low-dose = 0.28 +/- 0.02 vs K-1-control = 0.30 +/- 0.02; p = 0.42) compared to controls. Whole-brain V-T was decreased by 25% in the high-dose group (V-T-high-dose = 5.92 +/- 0.41 vs V-T-control = 7.82 +/- 0.38; p < 0.001) and by 6% in the low-dose group (V-T-low-dose = 7.35 +/- 0.38 vs V-T-control = 7.82 +/- 0.37; p = 0.38) compared to controls. k(2) values did not vary after treatment. The treatment did not affect the metabolism of [F-18]MC225. Western blot studies using the wholebrain tissue did not detect changes in the P-gp expression, however, preliminary results using isolated brain capillaries found an increasing trend up to 37% in treated rats. The decrease in K1 and VT values after treatment with the inducer indicates an increase in the P-gp functionality at the BBB of treated rats. Moreover, preliminary results using brain endothelial cells also sustained the increase in the P-gp expression. In conclusion, the results verify that MC111 induces P-gp expression and function at the BBB in rats. An increasing trend regarding the P-gp expression levels is found using western blot and an increased P-gp function is confirmed with [F-18]MC225 and PET.

Introducción. El estudio de variables antropométricas y genéticas son fundamentales como determinantes del rendimiento deportivo. Objetivo. El objetivo del estudio fue determinar el somatotipo y la frecuencia de genotipo y alelo de 𝜶-actinina 3 (ACTN3) R577X y enzima convertidora de angiotensina (ECA) I/D polimorfismo de jugadores de tenis de mesa chilenos. Método. Se estudiaron 24 tenimesistas varones (edad 22,1 ± 5,4) del ranking nacional de Chile. La obtención de ACTN3 y ECA se recogió por muestra la saliva y se analizaron mediante reacción cadena de la polimerasa convencional. La estructura corporal se caracterizó a través del método del somatotipo propuesto por Carter. A partir de estadísticas descriptiva, se analizaron los valores medios de somatotipo, frecuencia de clasificación y ubicación de somato carta, además, de valores de frecuencia de genotipo y alelo de ACTN3 R/X y ECA I/D polimorfismo de acuerdo con número de aparición y porcentaje.Resultados. Se evidenció un predominio de clasificación mesoendomórfica y endomesomórfica, una mayor frecuencia fenotípica XX con predominio de alelo X para el gen ACTN3 y mayor frecuencia DI con predominio de alelo D para ECA. Conclusión. El somatotipo de tenimesistas chilenos tiene una orientación hacia mesoendomorfía y un predominio XX y alelo X del gen ACTN3 y, predominio del genotipo DI y alelo D del gen ECA, estas características podrían ofrecer una ventaja genética en cuanto a niveles de fuerza y potencia muscular, posiblemente facilitando la práctica y el éxito competitivo en estos tenimesistas chilenos. Abstract. Introduction. The study of anthropometric and genetic variables are essential as determinants of sports performance. Objective. The objective of the study was to determine the somatotype and the frequency of genotype and allele of 𝜶-actinin 3 (ACTN3) R577X and angiotensin converting enzyme (RCT) I / D polymorphism of Chilean table tennis players. Method. 24 male table tennis players (age 22.1 x 5.4) of Chile's national rankings were studied. Obtaining ACTN3 and ACE was collected by sample of saliva and analyzed by polymerase chain in real time. The body structure was characterized through the somatotype method proposed by Carter. From descriptive statistics, the mean values of somatotype, frequency of classification and location of somato letter were analyzed, in addition, of genotype frequency values and allele of ACTN3 R/X and ECA I/D polymorphism according to number of occurrence and percentage. Results. It demonstrated a predominance of mesoendomorphy and endomorphy classification, a higher phenotypic frequency XX with predominance of allele X for the ACTN3 gene and higher frequency of DI allele with predomina D for ACE. Conclusion. The somatotype of Chilean tenimestists has an orientation towards mesoendomorphy and a predominance of the genotype XX and allele X of the ACTN3 gene and, predominance of the DI genotype and allele D of the ACE gene, these characteristics could offer a genetic advantage in terms of strength levels and muscle potency, possibly facilitating practice and competitive success in these Chilean tenimists.

Purpose: [18F]Fluoroethoxybenzovesamicol ([18F]FEOBV) is a radioligand for the vesicular acetylcholine transporter (VAChT), a marker of the cholinergic system. We evaluated the quantification of [18F]FEOBV in rats in control conditions and after partial saturation of VAChT using plasma and reference tissue input models and test-retest reliability. Procedure: Ninety-minute dynamic [18F]FEOBV PET scans with arterial blood sampling were performed in control rats and rats pretreated with 10 μg/kg FEOBV. Kinetic analyses were performed using one- (1TCM) and two-tissue compartmental models (2TCM), Logan and Patlak graphical analyses with metabolite-corrected plasma input, reference tissue Patlak with cerebellum as reference tissue, standard uptake value (SUV) and SUV ratio (SUVR) using 60- or 90-min acquisition. To assess test-retest reliability, two dynamic [18F]FEOBV scans were performed 1 week apart. Results: The 1TCM did not fit the data. Time-activity curves were more reliably estimated by the irreversible than the reversible 2TCM for 60 and 90 min as the influx rate Ki showed a lower coefficient of variation (COV, 14–24 %) than the volume of distribution VT (16–108 %). Patlak graphical analysis showed a good fit to the data for both acquisition times with a COV (12–27 %) comparable to the irreversible 2TCM. For 60 min, Logan analysis performed comparably to both irreversible models (COV 14–32 %) but showed lower sensitivity to VAChT saturation. Partial saturation of VAChT did not affect model selection when using plasma input. However, poor correlations were found between irreversible 2TCM and SUV and SUVR in partially saturated VAChT states. Test-retest reliability and intraclass correlation for SUV were good. Conclusion: [18F]FEOBV is best modeled using the irreversible 2TCM or Patlak graphical analysis. SUV should only be used if blood sampling is not possible.

Introduction Depression is characterized by behavioral, cognitive and physiological changes, imposing a major burden on the overall wellbeing of the patient. Some evidence indicates that social stress, changes in growth factors (e.g., brain-derived neurotrophic factor (BDNF)), and neuroinflammation are involved in the development and progression of the disease. The monoamine oxidase A inhibitor drug harmine was suggested to have both antidepressant and anti-inflammatory properties and may, therefore, be a potential candidate for treatment of depression. Aim The goal of this study was to assess the effects of harmine on behavior, brain BDNF levels, and microglia activation in control rats and a rat model of social stress. Material and methods Rats were submitted to 5 consecutive days of repeated social defeat (RSD) or control conditions. Animals were treated daily with harmine (15 mg/kg) or vehicle from day 3 until the end of the experiment. To assess the effects of harmine treatment on behavior, the sucrose preference test (SPT) was performed on days 1, 6, and 15, the open field test (OFT) on days 6 and 14, and the novel object recognition test (NOR) on day 16. Brain microgliosis was assessed using [11C]PBR-28 PET on day 17. Animals were terminated on day 17, and BDNF protein concentrations in the hippocampus and frontal cortex were analyzed using ELISA. Results RSD significantly decreased bodyweight and increased anxiety and anhedonia-related parameters in the OFT and SPT on day 6, but these behavioral effects were not observed anymore on day 14/15. Harmine treatment caused a significant reduction in bodyweight gain in both groups, induced anhedonia in the SPT on day 6, and significantly reduced the mobility and exploratory behavior of the animals in the OFT mainly on day 14. PET imaging and the NOR test did not show any significant effects on microglia activation and memory, respectively. BDNF protein concentrations in the hippocampus and frontal cortex were not significantly affected by either RSD or harmine treatment. Discussion Harmine was not able to reverse the acute effects of RSD on anxiety and anhedonia and even aggravated the effect of RSD on bodyweight loss. Moreover, harmine treatment caused unexpected side effects on general locomotion, both in RSD and control animals, but did not influence glial activation status and BDNF concentrations in the brain. In this model, RSD-induced stress was not strong enough to induce long-term effects on the behavior, neuroinflammation, or BDNF protein concentration. Thus, the efficacy of harmine treatment on these delayed parameters needs to be further evaluated in more severe models of chronic stress.

The interaction of dopaminergic and cholinergic neurotransmission in, e.g., Parkinson's disease has been well established. Here, D2 receptor antagonists were used to assess changes in [18F]-FEOBV binding to the vesicular acetylcholine transporter (VAChT) in rodents using positron emission tomography (PET). After pretreatment with either 10 mg/kg haloperidol, 1 mg/kg raclopride, or vehicle, 90 min dynamic PET scans were performed with arterial blood sampling. The net influx rate (Ki) was obtained from Patlak graphical analysis, using a metabolite-corrected plasma input function and dynamic PET data. [18F]-FEOBV concentration in whole-blood or plasma and the metabolite-corrected plasma input function were not significantly changed by the pretreatments (adjusted p > 0.07, Cohen's d 0.28-1.89) while the area-under-the-curve (AUC) of the parent fraction of [18F]-FEOBV was significantly higher after haloperidol treatment (adjusted p = 0.022, Cohen's d = 2.51) than in controls. Compared to controls, the AUC of [18F]-FEOBV, normalized for injected dose and body weight, was nonsignificantly increased in the striatum after haloperidol (adjusted p = 0.4, Cohen's d = 1.77) and raclopride (adjusted p = 0.052, Cohen's d = 1.49) treatment, respectively. No changes in the AUC of [18F]-FEOBV were found in the cerebellum (Cohen's d 0.63-0.74). Raclopride treatment nonsignificantly increased Ki in the striatum 1.3-fold compared to control rats (adjusted p = 0.1, Cohen's d = 1.1) while it reduced Ki in the cerebellum by 28% (adjusted p = 0.0004, Cohen's d = 2.2) compared to control rats. Pretreatment with haloperidol led to a nonsignificant reduction in Ki in the striatum (10%, adjusted p = 1, Cohen's d = 0.44) and a 40-50% lower Ki than controls in all other brain regions (adjusted p < 0.0005, Cohen's d = 3.3-4.7). The changes in Ki induced by the selective D2 receptor antagonist raclopride can in part be quantified using [18F]-FEOBV PET imaging. Haloperidol, a nonselective D2/σ receptor antagonist, either paradoxically decreased cholinergic activity or blocked off-target [18F]-FEOBV binding to σ receptors. Hence, further studies evaluating the binding of [18F]-FEOBV to σ receptors using selective σ receptor ligands are necessary.

Activation of the insula is found in all anxiety-related disorders and increased insular-prefrontal cortex (PFC) functional connectivity is associated with reduced anxiety. In this study, the combined stimulation of the insula and PFC using the dTMS H4 (insula+LPFC) and H2 (PFC) coils were used to reduce anxiety in 13 subjects experiencing occupational stress, and 55 participants suffering from generalized anxiety disorder (GAD). The combined HF stimulation of the insula and PFC significantly decreased anxiety scores according to the HARS, CAS, and STAI anxiety scales, leading to a reduction in anxiety according to HARS of 88.7% and 70.7% in participants with occupational stress and the clinical sample of participants diagnosed with GAD, respectively. The findings suggest that the prefrontal-insular axis is critical for the regulation of anxiety and its stimulation can be used for the treatment of anxiety in people suffering from occupational stress and GAD.

Astrocytes release gliotransmitters via connexin 43 (Cx43) hemichannels into neighboring synapses, which can modulate synaptic activity and are necessary for fear memory consolidation. However, the gliotransmitters released, and their mechanisms of action remain elusive. Here, we report that fear conditioning training elevated Cx43 hemichannel activity in astrocytes from the basolateral amygdala (BLA). The selective blockade of Cx43 hemichannels by microinfusion of TAT-Cx43L2 peptide into the BLA induced memory deficits 1 and 24 h after training, without affecting learning. The memory impairments were prevented by the co-injection of glutamate and D-serine, but not by the injection of either alone, suggesting a role for NMDA receptors (NMDAR). The incubation with TAT-Cx43L2 decreased NMDAR-mediated currents in BLA slices, effect that was also prevented by the addition of glutamate and D-serine. NMDARs in primary neuronal cultures were unaffected by TAT-Cx43L2, ruling out direct effects of the peptide on NMDARs. Finally, we show that D-serine permeates through purified Cx43 hemichannels reconstituted in liposomes. We propose that the release of glutamate and D-serine from astrocytes through Cx43 hemichannels is necessary for the activation of post-synaptic NMDARs during training, to allow for the formation of short-term and subsequent long-term memory, but not for learning per se.

Major depressive disorder (MDD) is considered a major global health burden, being the single largest contributor to global disability and suicides. Because of its complex multifactorial nature and the variety of symptoms observed in this disorder, still around 50% of MDD patients show no or incomplete response to pharmacological therapies. In this regard, studying the molecular interactions and risk factors of MDD is a key step to improve our knowledge of the etiology and the differences in the treatment response between patients. This thesis aimed to investigate the contribution of several underlying biological processes on the development of depressive behavior in animal models, such as steroidal hormone and monoamine signaling and neuroinflammation. We found that PET imaging is a useful tool to study the effects of sex hormones in the brain in a menopausal animal model, but that chronic stress was not a strong risk factor for developing depressive symptoms in this model. In addition, we showed in a stress model of depression that repeated social defeat induced neuroinflammation, but that this effect was not counteracted by the fast antidepressant ketamine or caffeine. In this animal model, we also showed that social stress caused delayed changes in dopaminergic and serotonergic transmission when depressive symptoms had already resolved. Finally, we observed that antidepressant therapy during pregnancy had a detrimental effect on cognition in the offspring. In conclusion, this thesis provides insight in different interactions between systems and risk factors, contributing to the general knowledge of MDD.

The increased incidence of depression in women going through peri-menopause suggests that fluctuations in estrogen levels may increase the risk of developing depression. Nonetheless, this psychiatric disorder is likely to be multifactorial and consequently an additional trigger may be needed to induce depression in this population. Stress could be such a trigger. We therefore investigated the effect of ovarian estrogen depletion and chronic mild stress (CMS) on depressive-like behavior and brain metabolism in female rats. Approximately 2 and 9 weeks after estrogen depletion by ovariectomy, behavioral changes were assessed in the open-field test and the forced swim test, and brain metabolism was measured with [18F]FDG PET imaging. A subset of animals was subjected to a 6-weeks CMS protocol starting 17 days after ovariectomy. Short-term estrogen depletion had a significant effect on brain metabolism in subcortical areas, but not on behavior. Differences in depressive-like behavior were only found after prolonged estrogen depletion, leading to an increased immobility time in the forced swim test. Prolonged estrogen depletion also resulted in an increase in glucose metabolism in frontal cortical areas and hippocampus, whereas a decrease glucose metabolism was found in temporal cortical areas, hypothalamus and brainstem. Neither short-term nor prolonged estrogen depletion caused anxiety-like behavior. Changes in body weight, behavior and brain glucose metabolism were not significantly affected by CMS. In conclusion, ovarian estrogen depletion resulted in changes in brain metabolism and depressive-like behavior, but these changes were not enhanced by CMS. ispartof: Psychoneuroendocrinology vol:115 pages:104610- ispartof: location:England status: published

Resumen La divulgación científica es imprescindible para consolidar el diálogo académico y el desarrollo científico-técnico. Ahora, mucha de la investigación que se hace y se divulga no produce el impacto esperado dado que las vías de divulgación no son las más adecuadas en algunos casos. Este trabajo tiene como objeto la revisión propositiva de criterios de selección de revistas científicas con el fin de la postulación de artículos para su publicación por autores nóveles. Así, plantea una guía para la escogencia de una revista científica que reúna las mejores condiciones en el ámbito de la visibilidad, acceso, impacto y calidad de la información. Abstract The popularization of science is essential to consolidate academic dialogue and scientific-technical development. Now, much of the research that is done and disseminated does not produce the expected impact since the means of dissemination are not the most appropriate in some cases. The purpose of this work is to review the selection criteria for scientific journals in order to submit articles for publication. Thus, it proposes a series of indicators that guide the selection of a journal that meets the best conditions in the field of visibility, access, impact and quality of information. Resumo A divulgação científica é essencial para consolidar o diálogo acadêmico e o desenvolvimento técnico-científico. Agora, grande parte da pesquisa realizada e disseminada não produz o impacto esperado, uma vez que as rotas de divulgação não são as mais adequadas em alguns casos. Este trabalho tem como objetivo propor uma revisão dos critérios de seleção de revistas científicas, a fim de solicitar artigos para publicação. Assim, gera uma série de indicadores que orientam a escolha de uma revista que atenda às melhores condições no campo da visibilidade, acesso, impacto e qualidade das informações.

[Ninety-minute dynamic [The 1TCM did not fit the data. Time-activity curves were more reliably estimated by the irreversible than the reversible 2TCM for 60 and 90 min as the influx rate K[

Coastal resident and pelagic nonresident bottlenose dolphins, Tursiops truncatus, have been described in north-central Chile. Using long-term residence data (over 13 years of photo-identification) and genetic mtDNA information, we analysed the social dyn

Biotic and abiotic factors determine presence and habitat use pattern of individuals within a population. In this study, presence, behavior, and resighting patterns of transient bottlenose dolphins (Tursiops truncatus) were evaluated in relation to upwelling and downwelling events in a marine reserve in North-Central Chile, between 2005 and 2009. The study period was divided into four phases according to wind direction and intensity: upwelling-favorable (UF), transition I (TI), convergence (Cv) or downwelling, and transition II (TII). Results show that transient bottlenose dolphins are an open population with low resighting rates. Highest occurrence and a largest number of transient dolphins were identified during 2009, probably due to an increase in prey availability. The most frequent behavior observed was traveling, followed by feeding and socializing. Traveling was mainly recorded in individuals seen only once and in years with low productivity. In contrast, feeding was observed in individuals seen two or more times, was similar among phases, and was more frequent in moreproductive years. Social behavior was associated with the highest resighting rates. This study documents how transient bottlenose dolphins use the area based on their resighting patterns and suggests that periods of upwelling and downwelling modulate behavior displayed by these dolphins within the area.

The human insula has been consistently reported to be overactivated in all anxiety disorders, activation which has been suggested to be proportional to the level of anxiety and shown to decrease with effective anxiolytic treatment. Nonetheless, studies evaluating the direct role of the insula in anxiety are lacking. Here, we set out to investigate the role of the rodent insula in anxiety by either inactivating different insular regions via microinjections of glutamatergic AMPA receptor antagonist CNQX or activating them by microinjection of GABA receptor antagonist bicuculline in rats, before measuring anxiety-like behavior using the elevated plus maze. Inactivation of caudal and medial insular regions induced anxiogenic effects, while their activation induced anxiolytic effects. In contrast, inactivation of more rostral areas induced anxiolytic effects and their activation, anxiogenic effects. These results suggest that the insula in the rat has a role in the modulation of anxiety-like behavior in rats, showing regional differences; rostral regions have an anxiogenic role, while medial and caudal regions have an anxiolytic role, with a transition area around bregma +0.5. The present study suggests that the insula has a direct role in anxiety.

Under normal conditions, connexin (Cx) hemichannels have a low open probability, which can increase under pathological conditions. Since hemichannels are permeable to relatively large molecules, their exacerbated activity has been linked to cell damage. Cx46 is highly expressed in the lens and its mutations have been associated to cataract formation, but it is unknown whether Cx46 has a role in non-genetic cataract formation (i.e. aging and diabetes). Nitric oxide (NO) is a key element in non-genetic cataract formation and Cx46 hemichannels have been shown to be sensitive to NO. The molecular mechanisms of the effects of NO on Cx46 are unknown, but are likely to result from Cx46 S-nitrosation (also known as S-nitrosylation). In this work, we found that lens opacity was correlated with Cx46 S-nitrosation in an animal model of cataract. Consistent with this result, a NO donor increased Cx46 S-nitrosation and hemichannel opening in HLE-B3 cells (cell line derived from human lens epithelial cells). Mutagenesis studies point to the cysteine located in the fourth transmembrane helix (TM4; human C212, rat C218) as the NO sensor. Electrophysiological studies performed in Xenopus oocytes revealed that rat Cx46 hemichannels are sensitive to different NO donors, and that the presence of C218 is necessary to observe the NO donors’ effects. Unexpectedly, gap junctions formed by Cx46 were insensitive to NO or the reducing agent dithiothreitol. We propose that increased hemichannel opening and/or changes in their electrophysiological properties of human Cx46 due to S-nitrosation of the cysteine in TM4 could be an important factor in cataract formation.

Over the past decade, the traditional description of astrocytes as being merely accessories to brain function has shifted to one in which their role has been pushed into the forefront of importance. Current views suggest that astrocytes:(1) are excitable through calcium fluctuations and respond to neurotransmitters released at synapses; (2) communicate with each other via calcium waves and release their own gliotransmitters which are essential for synaptic plasticity; (3) activate hundreds of synapses at once, thereby synchronizing neuronal activity and activating or inhibiting complete neuronal networks; (4) release vasoactive substances to the smooth muscle surrounding blood vessels enabling the coupling of circulation (blood flow) to local brain activity; and (5) release lactate in an activity-dependent manner in order to supply neuronal metabolic demand. In consequence, the role of astrocytes and astrocytic gliotransmitters is now believed to be critical for higher brain function and recently, evidence begins to gather suggesting that astrocytes are pivotal for learning and memory. All of the above are reviewed here while focusing on the role of astrocytes in memory and psychiatric disorders.

ANNICK MORGENTHALER, Centro de Investigaciones de Puerto Deseado, Universidad Nacional de la Patagonia Austral, Av. Prefectura s/n, (9050) Puerto Deseado, Santa Cruz, Argentina; JAVIER FERN ANDEZ, Darwin Expediciones, Espa~na 2251, (9050) Puerto Deseado, Santa Cruz, Argentina; RODRIGO MORAGA, Centro de Investigaci on Eutropia, Ahumada 131, Santiago, Chile; CARLOS OLAVARR IA, Fundaci on CEQUA, 21 de Mayo 1690, Punta Arenas, Chile and Centro de Investigaci on Eutropia, Ahumada 131, Santiago, Chile.

The complementarity of historical and contemporary processes contributes to understanding the genetic structure of continuously distributed marine species with high dispersal capabilities. Cephalorhynchus eutropia, has a continuous coastal distribution with strong genetic differentiation identified by nuclear DNA markers. We explored the historical dimension of this genetic differentiation between northern and southern populations to evaluate phylogeographic structure. Additionally, we conducted mtDNA and microsatellite analyses to detect past and recent demographic changes. The southern population was characterized by lower genetic diversity with a signal of population expansion, likely associated with ice retreat and habitat extension after the Last Glacial Maximum (LGM). In contrast, structure within the northern population was more consistent with stable historical population size. Approximate Bayesian Computation analyses suggested that during the LGM, C. eutropia persisted in the northern area; while the south was colonized by dispersal ~11,000 years ago followed by population expansion. This study shows that Chilean dolphin population structure is consistent with predictions from the Expansion-Contraction biogeographic model, with a poleward post-glacial shift revealed in current genetic structure. The results also confirm the validity of the population units previously identified, demonstrating their historical origin and highlighting the utility of integrating genetic markers with different temporal scale resolutions.

Indexación: Web of Science Under physiological conditions, astroglial hemichannels and pannexons allow the release of gliotransmitters from astrocytes. These gliotransmitters are critical in modulating synaptic transmission, plasticity and memory. However, recent evidence suggests that under pathological conditions, they may be central in the development of various neurodegenerative diseases. Here we review current literature on the role of astroglial hemichannels and pannexons in memory, stress and the development of neurodegenerative diseases, and propose that they are not only crucial for normal brain function, including memory, but also a potential target for the treatment of neurodegenerative diseases http://journal.frontiersin.org/article/10.3389/fnint.2016.00026/full

In spite of over 30 years of research, the role of the Insular Cortex (IC) in taste memory still remains elusive. To study the role of the IC in taste memory, we used conditioned taste aversion (CTA) for two different concentrations of saccharin; 0.1% which is highly preferred, and 0.5% which is non-preferred. Rats that had been IC lesioned bilaterally with ibotenic acid (15 mg/ml) before CTA showed significant learning impairments for saccharin 0.1% but not for saccharin 0.5%. To test CTA memory retention, rats lesioned a week after CTA training became completely amnesic for saccharin 0.1% yet only mildly impaired for saccharin 0.5%. Interestingly, the resulting preference for either concentration matched that of IC lesioned animals when exposed to either saccharin solution for the first time, but not those of sham animals, implying that IC lesions after CTA for either saccharin solution rendered complete amnesia, irrespective of the original preference. Our data indicate that an intact IC is essential for CTA learning and retention, as well as for an early neophobic response, but not for taste preference itself. Our data supports a model where the IC is involved in general taste rejection.

Se estimo la distribucion y la abundancia poblacional del lobo marino comun Otaria flavescens en la costa de Chile central durante los meses de enero y febrero de 2007. Adicionalmente, se analizaron los cambios en la abundancia de esta especie durante el periodo 1970-2007. Los censos poblacionales se basaron en fotografias tomadas desde embarcaciones menores o desde avionetas. Se contabilizaron un total de 16301 lobos marinos (IC = 16209-16375) en 33 colonias (6 reproductivas y 27 no reproductivas). Despues de corregir por la proporcion de animales en el agua y por crias no registradas al momento del censo, se estimo una abundancia promedio de 18179 (95 % CI = 17777-18851) lobos marinos en el area de estudio. El analisis de tendencia poblacional presento que desde 1970 a 1985 la abundancia-lobo marino com-mostro una tendencia positiva de aproximadamente 2.1 % ano-1. Sin embargo, entre 1985 a 1997, y entre 1997 a 2007, el numero de lobos marinos muestra una tendencia estable o ligeramente negativa de 0.4 ± 0.1 % ano-1 y 0.5 ± 0.1 % ano-1, respectivamente. Se sugiere que la sobreexplotacion y la declinacion de las principales pesquerias en la zona central de Chife podria haber impactado negativamente la distribucion y abundancia del lobo marino comun en el area de estudio.

Sex steroid hormones are major regulators of sexual characteristic among species. These hormones, however, are also produced in the brain. Steroidal hormone‐mediated signalling via the corresponding hormone receptors can influence brain function at the cellular level and thus affect behaviour and higher brain functions. Altered steroid hormone signalling has been associated with psychiatric disorders, such as anxiety and depression. Neurosteroids are also considered to have a neuroprotective effect in neurodegenerative diseases. So far, the role of steroid hormone receptors in physiological and pathological conditions has mainly been investigated post mortem on animal or human brain tissues. To study the dynamic interplay between sex steroids, their receptors, brain function and behaviour in psychiatric and neurological disorders in a longitudinal manner, however, non‐invasive techniques are needed. Positron emission tomography (PET) is a non‐invasive imaging tool that is used to quantitatively investigate a variety of physiological and biochemical parameters in vivo. PET uses radiotracers aimed at a specific target (eg, receptor, enzyme, transporter) to visualise the processes of interest. In this review, we discuss the current status of the use of PET imaging for studying sex steroid hormones in the brain. So far, PET has mainly been investigated as a tool to measure (changes in) sex hormone receptor expression in the brain, to measure a key enzyme in the steroid synthesis pathway (aromatase) and to evaluate the effects of hormonal treatment by imaging specific downstream processes in the brain. Although validated radiotracers for a number of targets are still warranted, PET can already be a useful technique for steroid hormone research and facilitate the translation of interesting findings in animal studies to clinical trials in patients.

Objective To evaluate the safety and assess the different symptom improvements found after a combined low-frequency primary motor cortex and high-frequency prefrontal cortex (PFC) stimulation using the deep TMS (dTMS) H-coil, as an add-on treatment for Parkinson’s disease (PD). Methods Forty-five PD patients underwent 14 dTMS sessions; each consisting of 1 Hz stimulation of the primary motor cortex for 15 min, followed by 10 Hz stimulation of the PFC for 15 min. Clinical assessments were performed, BEFORE, at the MIDDLE, and END of therapy as well as at FOLLOW-UP after 30 days, using Movement Disorder Society-Unified Parkinson’s Disease Rating Scale, TINETTI, UP&GO, SCOPA, HDRS21, Beck Depression Inventory, and self-applied daily motor assessment scales. Results Treatment was well-tolerated, without serious adverse effects. dTMS-induced significant PD symptom improvements at END and at FOLLOW-UP, in all subscales of the UPDRS, gait speed, depressive symptoms, balance, autonomic symptoms, and a 73% increase in daily ON time. Conclusion In the cohort of PD patients treated, dTMS was well-tolerated with only minor adverse effects. The dTMS-induced significant improvements in motor, postural, and motivational symptoms of PD patients and may potentiate concurrent levodopa treatment. Significance The present study demonstrates that dTMS may have a much wider spectrum of beneficial effects than previously reported for TMS, including enhancement of levodopa effects, suggesting that future clinical trials with dTMS should include a broader range of symptom measurements.

Pharmacological evidence associates type I dopamine receptors, including subtypes D1 and D5, with learning and memory. Analyses using genetic approaches have determined the relative contribution of dopamine receptor D1 (D1R) in cognitive tasks. However, the lack of drugs that can discriminate between D1R and D5R has made the pharmacological distinction between the two receptors difficult. Here, we aimed to determine the role of D5R in learning and memory. In this study we tested D5R knockout mice and wild-type littermates in a battery of behavioral tests, including memory, attention, locomotion, anxiety and motivational evaluations. Our results show that genetic deficiency of D5R significantly impairs performance in the Morris water maze paradigm, object location and object recognition memory, indicating a relevant role for D5R in spatial memory and recognition memory. Moreover, the lack of D5R resulted in decreased exploration and locomotion. In contrast, D5R deficiency had no impact on working memory, anxiety and depressive-like behavior, measured using the spontaneous alternation, open-field, tail suspension test, and forced swimming test. Electrophysiological analyses performed on hippocampal slices showed impairment in long-term-potentiation in mice lacking D5R. Further analyses at the molecular level showed that genetic deficiency of D5R results in a strong and selective reduction in the expression of the NMDA receptor subunit NR2B in the hippocampus. These findings demonstrate the relevant contribution of D5R in memory and suggest a functional interaction of D5R with hippocampal glutamatergic pathways.

Los estudios de variaciones de abundancia de las poblaciones a distintas escalas temporales permiten comprender como dichas poblaciones fluctuan en el tiempo y cuales son los factores que influyen sobre dichas variaciones. Se analizaron los patrones de abundancia del lobo marino comun (SASL, Otaria flavescens) a escalas diaria, mensual y anual en 2 loberas reproductivas del norte de Chile. Adicionalmente, se evaluo el efecto de El Nino sobre los patrones anuales de la especie. La abundancia de lobos marinos en Punta Negra (PN) disminuyo desde 1994 a 2011, mientras que en Punta Patache (PP) aumento, aunque el numero de crias fue proporcionalmente bajo. Los resultados demuestran un efecto importante de El Nino sobre la abundancia de lobos marinos, especialmente para hembras + juveniles en PN. La abundancia mensual de hembras y juveniles fue mayor en invierno, mientras que para machos adultos y subadultos no se encontro ningun patron. Finalmente, durante el dia la abundancia incrementa hasta llegar a un maximo hacia fines de la tarde, especialmente en el caso de hembras y juveniles. No se encontraron diferencias en los patrones de abundancia entre las epocas reproductiva y no reproductiva para ninguna de las clases de sexo/edad. Este estudio muestra que la abundancia en PP y PN muestra periodicidades anuales, mensuales y diarias, y que dichas periodicidades estan condicionadas tanto por factores intrinsecos (e.g., epoca reproductiva) como extrinsecos (e.g., hora del dia, El Nino). A escala anual, los resultados indican que aun a una escala local, las tendencias de abundancia en 2 colonias pueden ser diferentes.

This paper reports the presence and feeding activity of fin whales (Balaenoptera physalus) during the austral summers of 2004 and 2005 in coastal waters near the Reserva Nacional Pinguino de Humboldt, north of Chile. The main prey item of the species was identified as the euphausiid Euphausia mucronata. The presence of B. physalus is associated with a high concentration of potential prey probably produced by an upwelling system that is frequently detected slightly south of the study area during summer. This information is a contribution to the knowledge of distribution, feeding behavior, and diet of B. physalus. Additionally, it constitutes the first record of a direct observation of feeding activity of B. physalus along the Chilean coast.

Determining the role of the main gustatory cortical area within the insular cortex (IC), in conditioned taste aversion (CTA) has been elusive due to effective compensatory mechanisms that allow animals to learn in spite of lacking IC. IC lesions performed before CTA training induces mild if any memory impairments, while IC lesions done weeks after CTA produce amnesia. IC lesions before taste presentation have also been shown not to affect taste familiarity learning (attenuation of neophobia). This lack of effect could be either explained by compensation from other brain areas or by a lack of involvement of the IC in taste familiarity. To assess this issue, rats were bilaterally IC lesioned with ibotenic acid (200-300 nl.; 15 mg/ml) one week before or after taste familiarity, using either a preferred (0.1%) or a non-preferred (0.5%) saccharin solution. Rats lesioned before familiarity showed a decrease in neophobia to both solutions but no difference in their familiarity curve or their slope. When animals were familiarized and then IC lesioned, both IC lesioned groups treated the solutions as familiar, showing no differences from sham animals in their retention of familiarity. However, both lesioned groups showed increased latent inhibition (or impaired CTA) when CTA trained after repeated pre-exposures. The role of the IC in familiarity was also assessed using temporary inactivation of the IC, using bilateral micro-infusions of sodium channel blocker bupivacaine before each of 3 saccharin daily presentations. Intra-insular bupivacaine had no effects on familiarity acquisition, but did impair CTA learning in a different group of rats micro-infused before saccharin presentation in a CTA training protocol. Our data indicate that the IC is not essentially involved in acquisition or retention of taste familiarity, suggesting regional dissociation of areas involved in CTA and taste familiarity.

Connexins are a family of proteins that forms hemichannels that communicate the cytoplasm with the extracellular space. When two hemichannels [each one from two neighboring cells] make contact, they form a gap junction channel, which communicates the cytoplasm of adjacent cells. The molecular mechanisms that control the opening and closing of both functional hemichannels and gap junction channels is still matter of intense scrutiny. The lens is a transparent structure located in the anterior segment of the eye, which is critical for normal vision. Its main function is to refract the light, focusing it on the retina. Given this function, the lens requires great transparency and homogeneity which are attained by being avascular to avoid light scattering. To compensate for the lack of blood vessels, lens cells have intercellular connections formed by gap junction channels, which allow passive flux of nutrients and metabolites throughout the entire lens. Cataracts are produced by opacity of the lens, so less light reaches the retina. Recent evidence suggests that dysfunction of gap junction channels and hemichannels may induce cataract formation. Here we review general properties of gap junction channels and hemichannels. Then, we show the role of these channels in lens physiology and cataract formation with emphasis on rodent models lacking particular connexin genes and single point mutations in humans associated to hemichannel dysfunction. Finally, we raise the question of how environmental factors may affect hemichannel and gap junction activity and in turn induce or accelerate cataract formation by discussing the evidence that link molecular modifications [i.e phosphorylation and oxidation] of gap junction channels and hemichannels with cataract formation.

The Insular Cortex (IC) is a portion of the cerebral cortex folded deep within the lateral sulcus – in rodents surrounding the rhinal fissure between the temporal and frontal lobes. The IC was first described by J.C. Reil in 1809 [1], after whom it received the name “the island of Reil”. Historically, the IC has been mentioned with several names, including “the central lobe”, “the fifth lobe”, “intersylvian convolutions” and “intralobular gyri” (reviewed in [2]).

Recent in vitro evidence indicates that astrocytes can modulate synaptic plasticity by releasing neuroactive substances (gliotransmitters). However, whether gliotransmitter release from astrocytes is necessary for higher brain function in vivo, particularly for memory, as well as the contribution of connexin (Cx) hemichannels to gliotransmitter release, remain elusive. Here, we microinfused into the rat basolateral amygdala (BLA) TAT-Cx43L2, a peptide that selectively inhibits Cx43-hemichannel opening while maintaining synaptic transmission or interastrocyte gap junctional communication. In vivo blockade of Cx43 hemichannels during memory consolidation induced amnesia for auditory fear conditioning, as assessed 24 h after training, without affecting short-term memory, locomotion, or shock reactivity. The amnesic effect was transitory, specific for memory consolidation, and was confirmed after microinfusion of Gap27, another Cx43-hemichannel blocker. Learning capacity was recovered after coinfusion of TAT-Cx43L2 and a mixture of putative gliotransmitters (glutamate, glutamine, lactate, d-serine, glycine, and ATP). We propose that gliotransmitter release from astrocytes through Cx43 hemichannels is necessary for fear memory consolidation at the BLA. Thus, the present study is the first to demonstrate a physiological role for astroglial Cx43 hemichannels in brain function, making these channels a novel pharmacological target for the treatment of psychiatric disorders, including post-traumatic stress disorder.

Desde enero de 2007 y hasta marzo de 2008 se analizo la variacion de la abundancia del lobo marino comun Otaria flavescens en la lobera reproductiva Isla Chanaral, de acuerdo al sexo, clase de edad y estacion reproductiva. El mayor numero de lobos marinos en la lobera se registro durante el periodo reproductivo. Esta variacion se debio principalmente a la fluctuacion del numero de hembras, ya que esta clase de edad fue la mas importante en la colonia y mostro un aumento en su abundancia durante este periodo. No se registraron fluctuaciones estacionales en el numero de machos adultos, machos subadultos y juveniles. La proporcion de sexos durante la estacion reproductiva estuvo fuertemente sesgada hacia las hembras, mientras que fue cercana a 1:1 durante el resto del ano. Este estudio demuestra que la variacion en la abundancia y composicion por sexo y clase de edad del lobo marino comun en Isla Chanaral se relaciona principalmente con la actividad reproductiva.

Se analizaron los avistamientos de Eubalaena australis en aguas chilenas entre los años 1964 y 2008. Durante estos 44 años se han documentado 124 avistamientos con 232 ejemplares incluyendo a 39 crías. La distribución de los registros muestra tres zonas geográficas: i) aguas al norte de los 47°S, ii) aguas entre el estrecho de Magallanes y canal Beagle, y iii) aguas del paso Drake y Antártica. Mensualmente, una alta frecuencia de avistamientos se registró entre agosto y octubre. La mayoría de las crías se registraron al norte de los 41°S, concentrándose entre los 23°S y 25°S y entre los 32° y 36°S. Los tamaños grupales variaron entre 1 a 7 animales, registrándose en las aguas al norte de los 47°S un porcentaje levemente mayor de grupos en pares, mientras que bajo los 47°S, los grupos estuvieron constituidos mayoritariamente por animales solitarios. La tendencia de la población, considerando el total de animales registrados al norte de los 47°S, mostró una tasa de incremento positivo pero no significativa entre los años 1976 y 2008; sin embargo, en el caso de las crías, la tasa fue cercana a 0, sugiriéndose que ambas tasas estarían subestimadas. En consecuencia, es de absoluta necesidad aumentar el esfuerzo de observación de cetáceos, junto a un programa de estudios sistemático, incluyendo la foto-identificación y estudios moleculares, cuyos resultados permitan conocer la ecología y parámetros demográficos necesarios para evaluar esta especie de ballena catalogada `En Peligro Crítico' en aguas chilenas.

Con anterioridad, la orca falsa Pseudorca crassidens ha sido escasamente reportada en aguas chilenas. En esta nota damos a conocer tres nuevos registros. El primero corresponde a un grupo observado junto con tursiones (Tursiops truncatus) y calderones de aleta corta (Globicephala macrorhynchus) en bahia Cumberland, isla Robinson Crusoe frente a Chile central. El segundo registro corresponde a un individuo observado por trece meses entre Iquique y San Antonio en el norte y centro de Chile. El tercer registro corresponde a un grupo avistado cerca de la peninsula de Taitao. Se revisa la distribucion de esta especie en aguas chilenas.