Genome scans reveal signals of selection associated with pollution in fish populations of Basilichthys microlepidotus, an endemic species of Chile.

The Maipo River catchment is one of Chile's most polluted basins. In recent decades, discharges of untreated sewage and organic matter have caused eutrophication and water quality degradation. We employed the indigenous silverfish species Basilichthys microlepidotus as a model organism to investigate the process of adaptation and selection on genes influenced by pollution. Using variation at single nucleotide polymorphisms (SNPs), we determined the temporal stability of the population structure patterns previously identified in this species by varying SNPs. We also examined local adaptation to pollution-selected genes. Using the genotypes of 7684 loci in 180 individuals, we identified 429 and 700 loci that may be undergoing selection. We detected these loci using the FSTHET and ARLEQUIN outlier detection software, respectively. Both software packages simultaneously identified a total of 250 loci. B. microlepidotus' population structure did not change over time at contaminated or unpolluted sites. In addition, our analysis found: (i) selection of genes associated with pollution, consistent with observations in other organisms; (ii) identification of candidate genes that are functionally linked to the same biological processes, molecular functions and/or cellular components that previously showed differential expression in the same populations; and (iii) a candidate gene with differential expression and a non-synonymous substitution.

Biomarker selection depends on gene function and organ: the case of the cytochrome P450 family genes in freshwater fish exposed to chronic pollution.

Pollution and its effects have been of major concern in recent decades. Many strategies and markers have been developed to assess their effects on biota. Cytochrome P450 (CYP) genes have received significant attention in this context because of their relationship with detoxification and activation of exogenous compounds. While their expression has been identified as a pollution exposure biomarker, in most cases, it has been tested only after acute exposures and for CYP genes associated with exogenous compounds. To elucidate CYP gene expression patterns under chronic pollution exposure, we have used the silverside Basilichthys microlepidotus as a model, which inhabits the Maipo River Basin, a freshwater system with different pollution levels. We performed next-generation RNA sequencing of liver and gill tissues from polluted and non-polluted populations. We found most CYP genes were not dysregulated by pollution, and the seven genes that were present and differentially expressed in liver and gill were mainly downregulated. Three CYP genes associated with exogenous compounds showed differential expression in the gill, while four CYP genes associated with endogenous compounds showed differential expression in the liver. The findings presented here highlight the importance of CYP genes, his family, tissues and his interaction in the context of pollution biomarkers use.

Population genomic and biophysical modeling show different patterns of population connectivity in the spiny lobster Jasus frontalis inhabiting oceanic islands.

Knowledge about connectivity between populations is essential for the fisheries management of commercial species. The lobster Jasus frontalis inhabits two oceanic island groups, the Juan Fernández Archipelago and the Desventuradas Islands, separated by 800 km. Since this species is primarily exploited in the Juan Fernández Archipelago, knowledge of the connectivity patterns among islands is foundational for species management. Here, we used variability at single-nucleotide polymorphisms (SNPs) and individual-based modeling (IBM) to estimate the genetic structure and connectivity between J. frontalis populations in these island groups. The variability at 9090 SNPs suggests two genetic populations, one in the Juan Fernández Archipelago and one in the Desventuradas Islands. Furthermore, IBM suggests an asymmetric connectivity pattern, with particles moving from the Juan Fernández Archipelago to the Desventuradas Islands but not vice versa. Since the IBM analysis suggests asymmetric larval movement between the islands, and the genetic analysis indicates isolation between the Juan Fernández Archipelago and the Desventuradas Islands, larval retention mechanisms such as small-scale oceanographic processes or behavior could hinder larval movement between islands. This study highlights the importance of using more than one methodology to estimate population connectivity.

Is Your Kid Actin Out? A Series of Six Patients With Inherited Actin-Related Protein 2/3 Complex Subunit 1B Deficiency and Review of the Literature.

BACKGROUND: Hereditary actin-related protein 2/3 complex subunit 1B deficiency is characterized clinically by ear, skin, and lung infections, bleeding, eczema, food allergy, asthma, skin vasculitis, colitis, arthritis, short stature, and lymphadenopathy. OBJECTIVE: We aimed to describe the clinical, laboratory, and genetic features of six patients from four Mexican families. METHODS: We performed exome sequencing in patients of four families with suspected actinopathy, collected their data from medical records, and reviewed the literature for reports of other patients with actin-related protein 2/3 complex subunit 1B deficiency. RESULTS: Six patients from four families were included. All had recurrent infections, mainly bacterial pneumonia, and cellulitis. A total of 67% had eczema whereas 50% had food allergies, failure to thrive, hepatomegaly, and bleeding. Eosinophilia was found in all; 84% had thrombocytopenia, 67% had abnormal-size platelets and anemia. Serum levels of IgG, IgA, and IgE were highly increased in most; IgM was normal or low. T cells were decreased in 67% of patients, whereas B and NK cells were increased in half of patients. Two of the four probands had compound heterozygous variants. One patient was successfully transplanted. We identified 28 other patients whose most prevalent features were eczema, recurrent infections, failure to thrive, bleeding, diarrhea, allergies, vasculitis, eosinophilia, platelet abnormalities, high IgE/IgA, low T cells, and high B cells. CONCLUSION: Actin-related protein 2/3 complex subunit 1B deficiency has a variable and heterogeneous clinical spectrum, expanded by these cases to include keloid scars and Epstein-Barr virus chronic hepatitis. A novel deletion in exon 8 was shared by three unrelated families and might be the result of a founder effect.

Spatial and temporal stability in the genetic structure of a marine crab despite a biogeographic break.

Elucidating the processes responsible for maintaining the population connectivity of marine benthic species mediated by larval dispersal remains a fundamental question in marine ecology and fishery management. Understanding these processes becomes particularly important in areas with a biogeographic break and unidirectional water movement along the sides of the break. Based on variability at 4209 single-nucleotide polymorphisms in 234 individuals, we determine the genetic structure, temporal genetic stability, and gene flow among populations of the commercially important mola rock crab Metacarcinus edwardsii in a system in southern Chile with a biogeographic break at latitude 42°S. Specimens were collected at eight sites within its geographic distribution, with collection at four of these sites was performed twice. Using population genetic approaches, we found no evidence of geographic or temporal population differentiation. Similarly, we found no evidence of an effect on gene flow of the biogeographic break caused by the the West Wind Drift Current. Moreover, migration analyses supported gene flow among all sites but at different rates for different pairs of sites. Overall, our findings indicate that M. edwardsii comprises a single large population with high levels of gene flow among sites separated by over 1700 km and demonstrate temporal stability in its genetic structure.

[Penicillin allergy]. / Alergia a la penicilina.

Betalactams are the most widely used antimicrobials for their safety and efficacy. These include the penicillins, cephalosporins, carbapenems, and monobactams. Penicillin allergy ranks first in relation to drug allergy. 10 to 20 % of the population is labeled as allergic to it, often wrongly. Cross reaction is reported in 2 to 5 % between penicillins and cephalosporin. There is no cross reaction between penicillins and aztreonam, but there is with ceftazidime. All the mechanisms of the Gell and Coombs classification are included in the pathophysiology of hypersensitivity reactions to penicillin. Stratification according to risk allows us to take the most objective behavior to label the patient as allergic to. In the natural history of penicillin allergy, 80-90 % of patients lose this sensitivity by 10 years. If necessary, the patient can undergo a desensitization protocol. The immuno-allergist is a key piece in the selection of the patient, the elaboration of the challenge and desensitization protocols, in a controlled environment.

Los betalactámicos son los antimicrobianos más utilizados por su seguridad y eficacia. En este grupo se incluyen las penicilinas, las cefalosporinas, los carbapenémicos y los monobactámicos. La penicilina constituye la primera causa de alergia a medicamentos: 10 a 20 % de la población se etiqueta como alérgica a la misma, en muchas ocasiones erróneamente. Se ha reportado reacción cruzada entre penicilinas y cefalosporina en 2 a 5 %. No hay reacción cruzada entre penicilinas y aztreonam, pero sí con ceftazidima. En la fisiopatología de las reacciones de hipersensibilidad a penicilina se incluyen todos los mecanismos de la clasificación de Gell y Coombs. La estratificación de acuerdo con el riesgo permite tomar la decisión más objetiva para etiquetar al paciente como alérgico. En la evolución natural de la alergia a la penicilina, 80 a 90 % de los pacientes pierde dicha sensibilidad a los 10 años. De ser indispensable, el paciente puede ser sometido a un protocolo de desensibilización. El médico inmunoalergologo es una pieza clave en la selección del paciente, la elaboración de los protocolos de reto y la desensibilización en un ambiente controlado.

Geographical context outweighs habitat disturbance effects in explaining mistletoe population genetic differentiation at a regional scale.

Genetic differentiation depends on ecological and evolutionary processes that operate at different spatial and temporal scales. While the geographical context is likely to determine large-scale genetic variation patterns, habitat disturbance events will probably influence small-scale genetic diversity and gene flow patterns. Therefore, the genetic diversity patterns that we observe today result from the combination of both processes, but they are rarely assessed simultaneously. We determined the population structure and genetic diversity of a hemiparasitic mistletoe (Tristerix corymbosus) from the temperate rainforests of southern Chile to determine the effects of geographical context and habitat disturbance at a regional scale and if it is affected by the abundance and occurrence of its seed disperser mutualist (the arboreal marsupial Dromiciops gliroides). We genotyped 359 individuals from 12 populations using single nucleotide polymorphisms, across three different geographical contexts and four disturbance conditions. We also used camera traps to estimate the abundance and occurrence of the seed disperser. Our results suggest that genetic differences among populations are related more to geographical context than to habitat disturbance. However, as disturbance increased, D. gliroides abundance and occurrence decreased, and mistletoe inbreeding index (FIS ) increased. We also found highly uneven gene flow among study sites. Despite the high levels of disturbance that these temperate rainforests are facing, our results suggest that mistletoe genetic differentiation at a regional scale was more influenced by historical events. However, habitat disturbance can indirectly affect mistletoe population genetic differentiation via the seed dispersal process, which may increase levels of inbreeding.

High levels of connectivity over large distances in the diadematid sea urchin Centrostephanus sylviae.

Most benthic marine invertebrates with sedentary benthic adult phases have planktonic larvae that permit connectivity between geographically isolated populations. Planktonic larval duration and oceanographic processes are vital to connecting populations of species inhabiting remote and distant islands. In the present study, we analyzed the population genetic structure of the sea urchin Centrostephanus sylviae, which inhabits only the Juan Fernández Archipelago and the Desventuradas islands, separated by more than 800 km. For 92 individuals collected from Robinson Crusoe and Selkirk Islands (Juan Fernández Archipelago) and San Ambrosio Island (Desventuradas Islands), 7,067 single nucleotide polymorphisms (SNPs) were obtained. The results did not show a spatial genetic structure for C. sylviae; relative high migration rates were revealed between the islands. An analysis of the water circulation pattern in the area described a predominant northward water flow with periods of inverted flow, suggesting that larvae could move in both directions. Overall, this evidence suggests that C. sylviae comprises a single large population composed of individuals separated by more than 800 km.

Green, yellow or black? Genetic differentiation and adaptation signatures in a highly migratory marine turtle.

Marine species may exhibit genetic structure accompanied by phenotypic differentiation related to adaptation despite their high mobility. Two shape-based morphotypes have been identified for the green turtle (Chelonia mydas) in the Pacific Ocean: the south-central/western or yellow turtle and north-central/eastern or black turtle. The genetic differentiation between these morphotypes and the adaptation of the black turtle to environmentally contrasting conditions of the eastern Pacific region has remained a mystery for decades. Here we addressed both questions using a reduced-representation genome approach (Dartseq; 9473 neutral SNPs) and identifying candidate outlier loci (67 outlier SNPs) of biological relevance between shape-based morphotypes from eight Pacific foraging grounds (n = 158). Our results support genetic divergence between morphotypes, probably arising from strong natal homing behaviour. Genes and enriched biological functions linked to thermoregulation, hypoxia, melanism, morphogenesis, osmoregulation, diet and reproduction were found to be outliers for differentiation, providing evidence for adaptation of C. mydas to the eastern Pacific region and suggesting independent evolutionary trajectories of the shape-based morphotypes. Our findings support the evolutionary distinctness of the enigmatic black turtle and contribute to the adaptive research and conservation genomics of a long-lived and highly mobile vertebrate.

Selection of suitable reference genes for gene expression analysis in gills and liver of fish under field pollution conditions.

To understand the role of gene expression in adaptive variation, it is necessary to examine expression variation in an ecological context. Quantitative real-time PCR (qPCR) is considered the most accurate and reliable technique to measure gene expression and to validate the data obtained by RNA-seq; however, accurate normalization is crucial. In Chile, the freshwater silverside fish Basilichthys microlepidotus inhabits both polluted and nonpolluted areas, showing differential gene expression related to pollution. In this study, we infer the stability of six potential reference genes (tubulin alpha, hypoxanthine-guanine phosphoribosyltransferase, glyceraldehyde-3-phosphate dehydrogenase, beta-actin, 60S ribosomal protein L13, and 60S ribosomal protein L8) in the gills and liver of silverside individuals inhabiting polluted and nonpolluted areas. To validate the reference genes selected, the most and least stable reference genes were used to normalize two target transcripts, one for each organ. The RefFinder tool was used to analyze and identify the most stably expressed genes. The 60S ribosomal protein L8 gene was ranked as the most stable gene for both organs. Our results show that reference gene selection influences the detection of differences in the expression levels of target genes in different organs and, also highlighting candidate reference genes that could be used in field studies.

Highly Connected Populations and Temporal Stability in Allelic Frequencies of a Harvested Crab from the Southern Pacific Coast.

For marine invertebrates with a benthic adult form and a planktonic larva phase, the connectivity among populations is mainly based on larval dispersal. While an extended larval phase will promote gene flow, other factors such as an intensive fishery and geographical barriers could lead to changes in genetic variability. In this study, the population genetic structure of the commercial crab Metacarcinus edwardsii was analyzed along 700 km of the Chilean coast. The analysis, based on eight microsatellite loci genotyped from megalopae and adult crabs, considered temporal and spatial patterns of genetic variation. The results showed no evidence of spatial patterns in genetic structure, suggesting high connectivity among the sampling sites. The temporal analysis showed no evidence of changes in allele frequencies and no evidence of a recent bottleneck. The lack of spatial structure and allele variation over time could be explained by the interaction of factors such as i) low reproductive variance due to the capability of females to store sperm in the seminal receptacle, which can be used for successive broods, ii) high larval dispersal and iii) high individual reproductive output. Using our data as priors, a genetic modelling approach coincided, predicting this temporal and spatial stability. The same analysis showed that a reduction in population size leads to the loss of genetic variability in populations, as well as of the genetic cohesiveness between populations, pointing out the importance management for species under exploitation, such as M. edwardsii.

Tareas docentes que intencionan el conocimiento histórico cubano a través de la obra martiana / Teaching tasks that favor the Cuban historical knowledge through Marti's works

Fundamento: algunos textos de José Martí constituyen fuentes del conocimiento histórico que deben ser consultados y aprovechados por los educadores, en el proceso enseñanza aprendizaje de la Historia de Cuba. Objetivo: elaborar tareas docentes para la enseñanza de Historia de Cuba I integrando en ellas fragmentos de la obra martiana, en correspondencia con el contenido que se trate. Métodos: se realizó una investigación cualitativa en la Filial de Ciencias Médicas "Lidia Doce Sánchez" en el curso 2014-2015. Se emplearon métodos teóricos: análisis-síntesis, inducción-deducción e histórico-lógico, y empíricos: análisis documental, encuesta en forma de cuestionario a estudiantes de segundo año de la carrera y de entrevista a profesores de Historia de Cuba. Los resultados fueron triangulados metodológicamente. Resultados: en los programas se constató la necesidad de utilizar las obras martianas para un aprendizaje desarrollador, y el reforzamiento de valores humanos y revolucionarios; los alumnos coinciden en que no se ofrece un adecuado tratamiento a la obra martiana en los diferentes temas de Historia de Cuba I, y los profesores reconocen la importancia de incluir su análisis en las distintas formas organizativas de la enseñanza, y el estudio de su amplia bibliografía para valorar sus aportes sobre el pensamiento revolucionario cubano, por lo que se propusieron tareas docentes, las cuales fueron valoradas por criterio de especialistas. Conclusiones: las tareas docentes resultaron adecuadas por su carácter científico-pedagógico, su pertinencia y su funcionalidad para lograr un aprendizaje desarrollador e influir en el fortalecimiento de valores del futuro egresado de la carrera de Medicina.

Background: some of José Martí´s texts constitute sources of the historical knowledge that should be consulted and used by the professors, in the teaching-learning process of the History of Cuba. Objective: to elaborate teaching tasks for the teaching of History of Cuba I integrating in them fragments of Marti's work, in correspondence with the matching content. Methods: it was carried out a qualitative investigation in"Lidia Doce Sánchez" Medical Sciences University Site in the academic year 2014-2015. Theoretical methods were used: analysis-synthesis, induction-deduction and historical-logical, and empiric ones: documental analysis, a survey in questionnaire form was applied to students of second year of the career and in interview form to professors of History of Cuba. The results were methodologically triangulated. Results: the necessity of using Marti´s works was verified in the programs for a developing learning, and the reinforcement of human and revolutionary values; the students coincide in the sense that it isn't offered an appropriate treatment to Marti´s works in the different topics of History of Cuba I, and the professors recognize the importance of including its analysis in the different organizational forms of teaching, and the study of his wide bibliography to value his contributions on the Cuban revolutionary thought, teaching tasks were proposed , which were valued by the specialists' criteria. Conclusions: the teaching tasks were adequate because of their scientific-pedagogic character, their pertinence and functionality to achieve a developing learning and to influence in the strengthening of values of the future graduates of the Medicine career.

Software educativo, una herramienta útil para la asignatura de Historia de Cuba I / The educative software, a useful tool for the subject History of Cuba I

Se realizó una investigación con enfoque cualitativo en la Filial de Ciencias Médicas "Lidia Doce Sánchez" de Sagua la Grande, Villa Clara, de enero 2008 a marzo 2009, para diseñar un software educativo como medio de enseñanza para la asignatura de Historia de Cuba I de la carrera Medicina. El universo estuvo constituido por la totalidad de los estudiantes de segundo y tercer años que reciben el modelo tradicional y los profesores que lo imparten. Se utilizaron métodos teóricos y empíricos, y se realizó la triangulación como técnica de investigación cualitativa. Se constata que este programa no aborda contenidos de historia de la salud pública y la localidad por lo que se seleccionan temáticas agrupadas en tres temas por períodos históricos. Se diseñó un software educativo con estos contenidos para complementar la asignatura de Historia de Cuba I.

A qualitative research work was carried out in the "Lidia Doce Sánchez" Health University Site of Sagua la Grande municipality from January 2008 to March 2009 with the objective to design an educative software as a material aid for the subject History of Cuba I in the Medicine career. The universe comprises all the students of the second and third year of the traditional model as well as the professors who work with the subject. Empirical and theoretical methods were used and the information gathered was contrasted, as a technique of the qualitative research. It was detected that the syllabus doesn´t contain aspects on the History of Public Health in the location. There were selected three topics and they were grouped according to three different historical periods. It was designed an educative software with the contents on the History of Public Health in the location as a complement of the subject History of Cuba I.