Editorial: Let There Be Light: Biological Impact of Light Exposure in the Laboratory and the Clinic

Light is a relevant environmental factor due to its role in the synchronization of mammalian biological rhythms driven by the master circadian clock, the suprachiasmatic nucleus (SCN) (1– 4). Although light exposure has obvious beneficial properties on the quality of life, different articles have highlighted the deleterious effects of certain artificial lighting conditions that might affect the health and wellbeing of human beings and laboratory animals. Indeed, we are exposed to artificial light during the night and, in addition, constant lighting conditions or altered photoperiods are tools frequently used in experimental animals, neglecting the fact that these environments might influence the integrity of the nervous system and endocrine, physiological and behavioral-dependent processes that rely on the activity of the biological clock.Fil: Gonzalez, Monica M. C.. Instituto Ferrero de Neurología y Sueño; ArgentinaFil: Golombek, Diego Andres. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Quilmes. Departamento de Ciencia y Tecnología; Argentin

FRUIT REMOVAL BY LARGE AVIAN FRUGIVORES VARIES IN RELATION TO HABITAT QUALITY IN CONTINUOUS NEOTROPICAL RAINFOREST

Abstract ∙ Animal-mediated seed dispersal shapes key ecological processes including seedling recruitment and demography. Anthropogenic activities have substantively impacted tropical habitats, yet the degree of sensitivity exhibited by different frugivores to changes in habitat quality and how this may impact seed dispersal outcomes remains poorly understood. This is particularly true in contexts of low to moderate habitat alteration. To address this knowledge gap, we characterized the diurnal disperser community for an ecologically important canopy palm, Oenocarpus bataua, in continuous forest with differing degrees of human modification in northwest Ecuador. Our specific goal was to assess the degree to which visitation and fruit removal rates vary in relation to fine-scale forest structure. Frugivory and seed dispersal (i.e., removal of fruits with intact seeds) was dominated by three large bird species; smaller birds and some mammals visited fruiting trees but did not substantively contribute to seed dispersal. One of the three effective dispersal agents, the Long-wattled Umbrellabird (Cephalopterus penduliger), an endangered species threatened by habitat loss and degradation, exhibited higher visitation and fruit consumption rates in areas characterized by denser canopies, suggesting preference for foraging in undisturbed habitat. In contrast, two relatively common toucan species, Chocó Toucan (Ramphastos brevis) and Chestnut-mandibled Toucan (R. swainsonii), exhibited no variation in foraging behavior in relation to the habitat metrics we assessed. These findings highlight the degree to which differences in sensitivity to habitat disturbance among frugivore species may impact foraging ecology and suggest that variation in forest structure within continuous forest can impact seed removal and seed dispersal processes.Resumen ∙ La remoción de frutas por aves frugívoras de gran tamaño varía con respecto a la calidad de hábitat en bosques continuos Neotropicales La dispersión de semillas mediada por animales moldea procesos ecológicos claves como la posterior supervivencia y demografía de plántulas. Las actividades antropogénicas han afectado substancialmente los hábitats tropicales, sin embargo, el nivel de sensibilidad que presentan los diferentes frugívoros a cambios en la calidad del hábitat y cómo esto afecta a la dispersión de semillas, sigue siendo poco conocido. Esto es particularmente cierto en un contexto de poca a moderada alteración de hábitat. Para lograr comprender este vacío de conocimiento caracterizamos la comunidad de dispersores diurnos de una palma de dosel de importancia ecológica, Oenocarpus bataua, en bosques continuos con niveles diferentes de afectación humana en el noroccidente del Ecuador. Nuestro objetivo principal era de conocer el nivel en el cual las visitas y las tasas de remoción de frutas varía en relación a la estructura del bosque a escala muy fina. La frugivoría y la dispersión de semillas (es decir remoción de frutos con semillas intactas) fue dominada por tres especies de aves de gran tamaño; las aves más pequeñas y ciertos mamíferos visitaron palmas en fruto pero no contribuyeron substancialmente a la dispersión de semillas. Uno de los tres agentes de dispersión efectiva – el Pájaro Toro (Cephalopterus penduliger), una especie amenazada debido a la pérdida y degradación de su hábitat – realizó un mayor número de visitas y tasa de consumo de frutos en áreas caracterizadas por doseles más densos, lo cual sugiere una preferencia de forrajeo en hábitats no alterados. Por el contrario, dos especies relativamente comunes de tucanes, Tucán del Chocó (Ramphastos brevis) y Tucán de Pico Castaño (R. swainsonii), no presentaron diferencias en el comportamiento de forrajeo con respecto a las métricas de hábitat que nosotros utilizamos. Estos hallazgos resaltan el nivel en el cual diferencias en la sensibilidad a la alteración del hábitat entre especies frugívoras pueden impactar la ecología de forrajeo. Sugiere también que la variación en la estructura del bosque dentro de bosques continuos puede impactar la remoción de semillas y el proceso de dispersión de las mismas

The Emotional Word-Emotional Face Stroop task in the ABCD study: Psychometric validation and associations with measures of cognition and psychopathology

Characterizing the interactions among attention, cognitive control, and emotion during adolescence may provide important insights into why this critical developmental period coincides with a dramatic increase in risk for psychopathology. However, it has proven challenging to develop a single neurobehavioral task that simultaneously engages and differentially measures these diverse domains. In the current study, we describe properties of performance on the Emotional Word-Emotional Face Stroop (EWEFS) task in the Adolescent Brain Cognitive Development (ABCD) Study, a task that allows researchers to concurrently measure processing speed/attentional vigilance (i.e., performance on congruent trials), inhibitory control (i.e., Stroop interference effect), and emotional information processing (i.e., difference in performance on trials with happy as compared to angry distracting faces). We first demonstrate that the task manipulations worked as designed and that Stroop performance is associated with multiple cognitive constructs derived from different measures at a prior time point. We then show that Stroop metrics tapping these three domains are preferentially associated with aspects of externalizing psychopathology and inattention. These results highlight the potential of the EWEFS task to help elucidate the longitudinal dynamics of attention, inhibitory control, and emotion across adolescent development, dynamics which may be altered by level of psychopathology

Decolorization of synthetic melanoidins-containing wastewater by a bacterial consortium

The presence of melanoidins in molasses wastewater leads to water pollution both due to its dark brown color and its COD contents. In this study, a bacterial consortium isolated from waterfall sediment was tested for its decolorization. The identification of culturable bacteria by 16S rDNA based approach showed that the consortium composed of Klebsiella oxytoca, Serratia mercescens, Citrobacter sp. and unknown bacterium. In the context of academic study, prevention on the difficulties of providing effluent as well as its variations in compositions, several synthetic media prepared with respect to color and COD contents based on analysis of molasses wastewater, i.e., Viandox sauce (13.5% v/v), caramel (30% w/v), beet molasses wastewater (41.5% v/v) and sugarcane molasses wastewater (20% v/v) were used for decolorization using consortium with color removal 9.5, 1.13, 8.02 and 17.5%, respectively, within 2 days. However, Viandox sauce was retained for further study. The effect of initial pH and Viandox concentration on decolorization and growth of bacterial consortium were further determined. The highest decolorization of 18.3% was achieved at pH 4 after 2 day of incubation. Experiments on fresh or used medium and used or fresh bacterial cells, led to conclusion that the limitation of decolorization was due to nutritional deficiency. The effect of aeration on decolorization was also carried out in 2 L laboratory-scale suspended cell bioreactor. The maximum decolorization was 19.3% with aeration at KLa = 2.5836 h-1 (0.1 vvm)

Associations Between Methylation of Paternally Expressed Gene 3 (PEG3), Cervical Intraepithelial Neoplasia and Invasive Cervical Cancer.

Cytology-based screening for invasive cervical cancer (ICC) lacks sensitivity and specificity to discriminate between cervical intraepithelial neoplasia (CIN) likely to persist or progress from cases likely to resolve. Genome-wide approaches have been used to identify DNA methylation marks associated with CIN persistence or progression. However, associations between DNA methylation marks and CIN or ICC remain weak and inconsistent. Between 2008-2009, we conducted a hospital-based, case-control study among 213 Tanzania women with CIN 1/2/3 or ICC. We collected questionnaire data, biopsies, peripheral blood, cervical scrapes, Human papillomavirus (HPV) and HIV-1 infection status. We assessed PEG3 methylation status by bisulfite pyrosequencing. Multinomial logistic regression was used to estimate odds ratios (OR) and confidence intervals (CI 95%) for associations between PEG3 methylation status and CIN or ICC. After adjusting for age, gravidity, hormonal contraceptive use and HPV infection, a 5% increase in PEG3 DNA methylation was associated with increased risk for ICC (OR = 1.6; 95% CI 1.2-2.1). HPV infection was associated with a higher risk of CIN1-3 (OR = 15.7; 95% CI 5.7-48.6) and ICC (OR = 29.5, 95% CI 6.3-38.4). Infection with high risk HPV was correlated with mean PEG3 differentially methylated regions (DMRs) methylation (r = 0.34 p<0.0001), while the correlation with low risk HPV infection was weaker (r = 0.16 p = 0.047). Although small sample size limits inference, these data support that PEG3 methylation status has potential as a molecular target for inclusion in CIN screening to improve prediction of progression. Impact statement: We present the first evidence that aberrant methylation of the PEG3 DMR is an important co-factor in the development of Invasive cervical carcinoma (ICC), especially among women infected with high risk HPV. Our results show that a five percent increase in DNA methylation of PEG3 is associated with a 1.6-fold increase ICC risk. Suggesting PEG3 methylation status may be useful as a molecular marker for CIN screening to improve prediction of cases likely to progress

The Role of Parvalbumin-positive Interneurons in Auditory Steady-State Response Deficits in Schizophrenia

© The Author(s) 2019. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.Despite an increasing body of evidence demonstrating subcellular alterations in parvalbumin-positive (PV+) interneurons in schizophrenia, their functional consequences remain elusive. Since PV+ interneurons are involved in the generation of fast cortical rhythms, these changes have been hypothesized to contribute to well-established alterations of beta and gamma range oscillations in patients suffering from schizophrenia. However, the precise role of these alterations and the role of different subtypes of PV+ interneurons is still unclear. Here we used a computational model of auditory steady-state response (ASSR) deficits in schizophrenia. We investigated the differential effects of decelerated synaptic dynamics, caused by subcellular alterations at two subtypes of PV+ interneurons: basket cells and chandelier cells. Our simulations suggest that subcellular alterations at basket cell synapses rather than chandelier cell synapses are the main contributor to these deficits. Particularly, basket cells might serve as target for innovative therapeutic interventions aiming at reversing the oscillatory deficits.Peer reviewe

Assessing the carcinogenic potential of low-dose exposures to chemical mixtures in the environment: the challenge ahead.

Lifestyle factors are responsible for a considerable portion of cancer incidence worldwide, but credible estimates from the World Health Organization and the International Agency for Research on Cancer (IARC) suggest that the fraction of cancers attributable to toxic environmental exposures is between 7% and 19%. To explore the hypothesis that low-dose exposures to mixtures of chemicals in the environment may be combining to contribute to environmental carcinogenesis, we reviewed 11 hallmark phenotypes of cancer, multiple priority target sites for disruption in each area and prototypical chemical disruptors for all targets, this included dose-response characterizations, evidence of low-dose effects and cross-hallmark effects for all targets and chemicals. In total, 85 examples of chemicals were reviewed for actions on key pathways/mechanisms related to carcinogenesis. Only 15% (13/85) were found to have evidence of a dose-response threshold, whereas 59% (50/85) exerted low-dose effects. No dose-response information was found for the remaining 26% (22/85). Our analysis suggests that the cumulative effects of individual (non-carcinogenic) chemicals acting on different pathways, and a variety of related systems, organs, tissues and cells could plausibly conspire to produce carcinogenic synergies. Additional basic research on carcinogenesis and research focused on low-dose effects of chemical mixtures needs to be rigorously pursued before the merits of this hypothesis can be further advanced. However, the structure of the World Health Organization International Programme on Chemical Safety 'Mode of Action' framework should be revisited as it has inherent weaknesses that are not fully aligned with our current understanding of cancer biology

Metabolites related to purine catabolism and risk of type 2 diabetes incidence; modifying efects of the TCF7L2-rs7903146 polymorphism

Studies examining associations between purine metabolites and type 2 diabetes (T2D) are limited. We prospectively examined associations between plasma levels of purine metabolites with T2D risk and the modifying effects of transcription factor-7-like-2 (TCF7L2) rs7903146 polymorphism on these associations. This is a case-cohort design study within the PREDIMED study, with 251 incident T2D cases and a random sample of 694 participants (641 non-cases and 53 overlapping cases) without T2D at baseline (median follow-up: 3.8 years). Metabolites were semi-quantitatively profiled with LC-MS/MS. Cox regression analysis revealed that high plasma allantoin levels, including allantoin-to-uric acid ratio and high xanthine-to-hypoxanthine ratio were inversely and positively associated with T2D risk, respectively, independently of classical risk factors. Elevated plasma xanthine and inosine levels were associated with a higher T2D risk in homozygous carriers of the TCF7L2-rs7903146 T-allele. The potential mechanisms linking the aforementioned purine metabolites and T2D risk must be also further investigated

Dissociation of virtual photons in events with a leading proton at HERA

The ZEUS detector has been used to study dissociation of virtual photons in events with a leading proton, gamma^* p -> X p, in e^+p collisions at HERA. The data cover photon virtualities in two ranges, 0.03<Q^2<0.60 GeV^2 and 2<Q^2<100 GeV^2, with M_X>1.5 GeV, where M_X is the mass of the hadronic final state, X. Events were required to have a leading proton, detected in the ZEUS leading proton spectrometer, carrying at least 90% of the incoming proton energy. The cross section is presented as a function of t, the squared four-momentum transfer at the proton vertex, Phi, the azimuthal angle between the positron scattering plane and the proton scattering plane, and Q^2. The data are presented in terms of the diffractive structure function, F_2^D(3). A next-to-leading-order QCD fit to the higher-Q^2 data set and to previously published diffractive charm production data is presented