Genomes of the Orestias pupfish from the Andean Altiplano shed light on their evolutionary history and phylogenetic relationships within Cyprinodontiformes.

BACKGROUND: To unravel the evolutionary history of a complex group, a comprehensive reconstruction of its phylogenetic relationships is crucial. This requires meticulous taxon sampling and careful consideration of multiple characters to ensure a complete and accurate reconstruction. The phylogenetic position of the Orestias genus has been estimated partly on unavailable or incomplete information. As a consequence, it was assigned to the family Cyprindontidae, relating this Andean fish to other geographically distant genera distributed in the Mediterranean, Middle East and North and Central America. In this study, using complete genome sequencing, we aim to clarify the phylogenetic position of Orestias within the Cyprinodontiformes order. RESULTS: We sequenced the genome of three Orestias species from the Andean Altiplano. Our analysis revealed that the small genome size in this genus (~ 0.7 Gb) was caused by a contraction in transposable element (TE) content, particularly in DNA elements and short interspersed nuclear elements (SINEs). Using predicted gene sequences, we generated a phylogenetic tree of Cyprinodontiformes using 902 orthologs extracted from all 32 available genomes as well as three outgroup species. We complemented this analysis with a phylogenetic reconstruction and time calibration considering 12 molecular markers (eight nuclear and four mitochondrial genes) and a stratified taxon sampling to consider 198 species of nearly all families and genera of this order. Overall, our results show that phylogenetic closeness is directly related to geographical distance. Importantly, we found that Orestias is not part of the Cyprinodontidae family, and that it is more closely related to the South American fish fauna, being the Fluviphylacidae the closest sister group. CONCLUSIONS: The evolutionary history of the Orestias genus is linked to the South American ichthyofauna and it should no longer be considered a member of the Cyprinodontidae family. Instead, we submit that Orestias belongs to the Orestiidae family, as suggested by Freyhof et al. (2017), and that it is the sister group of the Fluviphylacidae family, distributed in the Amazonian and Orinoco basins. These two groups likely diverged during the Late Eocene concomitant with hydrogeological changes in the South American landscape.

Lysin and Lytic Phages Reduce Vibrio Counts in Live Feed and Fish Larvae.

Vibrio species are naturally found in estuarine and marine ecosystems, but are also recognized as significant human enteropathogens, often linked to seafood-related illnesses. In aquaculture settings, Vibrio poses a substantial risk of infectious diseases, resulting in considerable stock losses and prompting the use of antimicrobials. However, this practice contributes to the proliferation of antimicrobial-resistant (AMR) bacteria and resistance genes. Our investigation aimed to explore the potential of biological agents such as bacteriophage CH20 and endolysin LysVPp1 in reducing Vibrio bacterial loads in both rotifer and fish larvae. LysVPp1's lytic activity was assessed by measuring absorbance reduction against various pathogenic Vibrio strains. Phage CH20 exhibited a limited host range, affecting only Vibrio alginolyticus GV09, a highly pathogenic strain. Both CH20 and LysVPp1 were evaluated for their effectiveness in reducing Vibrio load in rotifers or fish larvae through short-setting bioassays. Our results demonstrated the significant lytic effect of endolysin LysVPp1 on strains of Vibrio alginolyticus, Vibrio parahaemolyticus, and Vibrio splendidus. Furthermore, we have showcased the feasibility of reducing the load of pathogenic Vibrio in live feed and fish larvae by using a non-antibiotic-based approach, such as lytic phage and endolysin LysVPp1, thus contributing to the progress of a sustainable aquaculture from a One Health perspective.

DNA sequencing in the classroom: complete genome sequence of two earwig (Dermaptera; Insecta) species

BACKGROUND: Despite representing the largest fraction of animal life, the number of insect species whose genome has been sequenced is barely in the hundreds. The order Dermaptera (the earwigs) suffers from a lack of genomic information despite its unique position as one of the basally derived insect groups and its importance in agroecosystems. As part of a national educational and outreach program in genomics, a plan was formulated to engage the participation of high school students in a genome sequencing project. Students from twelve schools across Chile were instructed to capture earwig specimens in their geographical area, to identify them and to provide material for genome sequencing to be carried out by themselves in their schools. RESULTS: The school students collected specimens from two cosmopolitan earwig species: Euborellia annulipes (Fam. Anisolabididae) and Forficula auricularia (Fam. Forficulidae). Genomic DNA was extracted and, with the help of scientific teams that traveled to the schools, was sequenced using nanopore sequencers. The sequence data obtained for both species was assembled and annotated. We obtained genome sizes of 1.18 Gb (F. auricularia) and 0.94 Gb (E. annulipes) with the number of predicted protein coding genes being 31,800 and 40,000, respectively. Our analysis showed that we were able to capture a high percentage (≥ 93%) of conserved proteins indicating genomes that are useful for comparative and functional analysis. We were also able to characterize structural elements such as repetitive sequences and non-coding RNA genes. Finally, functional categories of genes that are overrepresented in each species suggest important differences in the process underlying the formation of germ cells, and modes of reproduction between them, features that are one of the distinguishing biological properties that characterize these two distant families of Dermaptera. CONCLUSIONS: This work represents an unprecedented instance where the scientific and lay community have come together to collaborate in a genome sequencing project. The versatility and accessibility of nanopore sequencers was key to the success of the initiative. We were able to obtain full genome sequences of two important and widely distributed species of insects which had not been analyzed at this level previously. The data made available by the project should illuminate future studies on the Dermaptera.

Intoxicaciones con rodenticidas superwarfarínicos / Superwarfarin rodenticide poisoning

Introducción: en la actualidad existe utilización masiva de rodenticidas y su venta no está restringida al público. Las etiologías de intoxicación por estos agentes son variadas pudiendo ser de tipo intencional o accidental. Objetivo: analizar estudios realizados en torno a intoxicaciones con rodenticidas superwarfarínicos en humanos con el propósito de reunir información que oriente a un adecuado tratamiento. Metodología: se realizó una revisión integradora en las bases de datos electrónicas PubMed, TripDataBase, Cochrane, además de Google Scholar y SciELO, libros de divulgación científica, documentos de convenciones, páginas web de instituciones públicas, privadas y artículos vinculados a efectos, cuadro clínico y tratamiento de exposiciones a rodenticidas en seres humanos. Se analizaron los documentos y la información se organizó en tres temáticas: toxicidad de los rodenticidas superwarfarínicos, cuadro clínico y tratamiento médico, y rodenticidas no anticoagulantes disponibles en Chile. Resultados: la dosis tóxica mínima reportada en adultos es de 1 mg de principio activo; en pacientes pediátricos ingestas accidentales rara vez producen síntomas. Los síntomas se observan de forma tardía y su toxicidad es variable. El examen de elección es el International Normalized Ratio (INR) y se realiza en todo paciente con factores de riesgo presentes. El antídoto no se administra de forma profiláctica y la dosis se ajusta individualmente. Conclusión: en niños las ingestas accidentales no son riesgosas por lo que pueden ser observados en el hogar. Pacientes con ingestas masivas requieren controles de INR por meses por lo que es importante que posterior al alta médica exista una óptima coordinación con nivel primario de atención.

Introduction: Currently there is a widespread use of rodenticides, unrestricted to the public. The exposure to these agents may varied being intentional or accidental. Objective: To analyze studies about superwarfarin poisoning in humans, with the purpose of gathering information to guide proper treatment. Methodology: It was conducted an integrative review in the electronic databases PubMed, TripDataBase, Cochrane, Google Scholar and SciELO, science books (reference textbooks), convention documents, websites from public and private institutions and articles about the effects, clinical manifestations and treatment of human exposures to rodenticides. Documents were analyzed and the information organized into three themes: superwarfarin toxicity, clinical features and medical treatment, and non-anticoagulant rodenticides available in Chile. Results: In adults, the minimum dose reported to cause toxicity is 1 mg of active ingredient. In pediatric patients, accidental intakes rarely produce symptoms. The symptoms of poisoning are usually delayed and its toxicity is variable. The test of choice is International Normalized Ratio (INR) and it is performed in all patients with risk factors. The antidote must not be administered prophylactically and the dose is adjusted individually. Conclusions: Accidental intakes in children are not risky and they can be observed at home. Patients with massive intakes require INR monitoring for months so, it is important that an optimal coordination with primary care facilities still exists after medical discharge.

Intoxicaciones con rodenticidas superwarfarínicos / Superwarfarin rodenticide poisoning

Introducción: en la actualidad existe utilización masiva de rodenticidas y su venta no está restringida al público. Las etiologías de intoxicación por estos agentes son variadas pudiendo ser de tipo intencional o accidental. Objetivo: analizar estudios realizados en torno a intoxicaciones con rodenticidas superwarfarínicos en humanos con el propósito de reunir información que oriente a un adecuado tratamiento. Metodología: se realizó una revisión integradora en las bases de datos electrónicas PubMed, TripDataBase, Cochrane, además de Google Scholar y SciELO, libros de divulgación científica, documentos de convenciones, páginas web de instituciones públicas, privadas y artículos vinculados a efectos, cuadro clínico y tratamiento de exposiciones a rodenticidas en seres humanos. Se analizaron los documentos y la información se organizó en tres temáticas: toxicidad de los rodenticidas superwarfarínicos, cuadro clínico y tratamiento médico, y rodenticidas no anticoagulantes disponibles en Chile. Resultados: la dosis tóxica mínima reportada en adultos es de 1 mg de principio activo; en pacientes pediátricos ingestas accidentales rara vez producen síntomas. Los síntomas se observan de forma tardía y su toxicidad es variable. El examen de elección es el International Normalized Ratio (INR) y se realiza en todo paciente con factores de riesgo presentes. El antídoto no se administra de forma profiláctica y la dosis se ajusta individualmente. Conclusión: en niños las ingestas accidentales no son riesgosas por lo que pueden ser observados en el hogar. Pacientes con ingestas masivas requieren controles de INR por meses por lo que es importante que posterior al alta médica exista una óptima coordinación con nivel primario de atención.(AU)

Introduction: Currently there is a widespread use of rodenticides, unrestricted to the public. The exposure to these agents may varied being intentional or accidental. Objective: To analyze studies about superwarfarin poisoning in humans, with the purpose of gathering information to guide proper treatment. Methodology: It was conducted an integrative review in the electronic databases PubMed, TripDataBase, Cochrane, Google Scholar and SciELO, science books (reference textbooks), convention documents, websites from public and private institutions and articles about the effects, clinical manifestations and treatment of human exposures to rodenticides. Documents were analyzed and the information organized into three themes: superwarfarin toxicity, clinical features and medical treatment, and non-anticoagulant rodenticides available in Chile. Results: In adults, the minimum dose reported to cause toxicity is 1 mg of active ingredient. In pediatric patients, accidental intakes rarely produce symptoms. The symptoms of poisoning are usually delayed and its toxicity is variable. The test of choice is International Normalized Ratio (INR) and it is performed in all patients with risk factors. The antidote must not be administered prophylactically and the dose is adjusted individually. Conclusions: Accidental intakes in children are not risky and they can be observed at home. Patients with massive intakes require INR monitoring for months so, it is important that an optimal coordination with primary care facilities still exists after medical discharge.(AU)

Variables perinatales de recién nacidos de madres Aymara sugieren adaptación genética a la altura / Perinatal variables from newborns of Aymara mothers suggest a genetic adaptation to high altitude

Background: Studies performed in Andean populations living in high altitude, indicate that the reduced availability of oxygen could be associated to both a fetal growth retardation and a lower birth weight. These variables are predictive of morbidity and mortality during the first year of life. Aim: To study perinatal variables of newborns of mothers living at contrasting altitudinal levels, harboring different degrees of Aymara ancestry. Subjects and Methods: Review of medical records of 5,295 women whose deliveries occurred between February 2004 and August 2010. Information was obtained on place of residence, grouped into two categories: coast (150 to 3,000 m) and high plateau (3,000 to 4,300 m), ancestry was estimated using number of Aymara surnames that were homologated to percentages of Amerindian admixture, gestational age, birth weight, height, head circumference and obstetric variables. Results: Gestational age showed a tendency to increase and birth weight, height and head circumference to decrease with altitude of residence. Only weight reached statistical significance. Women with Aymara ancestry gave birth to children with a significantly higher gestational age, weight and cranial circumference. Conclusions: Altitude of residence is related to a decrease in perinatal variables that proved to be less pronounced in newborns of mothers with a higher degree of Aymara ancestry. Results suggest a genetic adaptation to hypoxia that could be related to candidate genes linked to the capture, transport or utilization of oxygen.