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.

Influence of dietary oils rich in omega-6 or omega-3 fatty acids on rumen microbiome of dairy cows.

The objective of this study was to compare the effect of supplementing dairy cow diets with contrasting sources of omega-6 (soybean oil) and omega-3 (fish oil) PUFA on rumen microbiome. For 63 d, 15 mid-lactating cows were fed a control diet (n = 5 cows; no fat supplement) or control diet supplemented with 2.9% dry matter (DM) of either soybean oil (SO; n = 5 cows) or fish oil (FO; n = 5 cows). Ruminal contents were collected on days 0, 21, 42, and 63 for 16S rRNA gene sequencing. Beta diversity and Shannon, Simpson and Chao1 diversity indices were not affected by dietary treatments. In terms of core microbiome, Succiniclasticum, Prevotella, Rikenellaceae_RC9_gut_group, and NK4A214_group were the most prevalent taxa regardless of treatments. Bifidobacterium was absent in SO diet, Acetitomaculum was absent in FO, and Sharpea was only detected in SO. Overall, results showed that at 2.9% DM supplementation of either SO or FO over 63 days in dairy cow diets does not cause major impact on bacterial community composition and thus is recommended as feeding practice.

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.

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.

Genome sequencing and transcriptomic analysis of the Andean killifish Orestias ascotanensis reveals adaptation to high-altitude aquatic life.

Orestias ascotanensis (Cyprinodontidae) is a teleost pupfish endemic to springs feeding into the Ascotan saltpan in the Chilean Altiplano (3,700 m.a.s.l.) and represents an opportunity to study adaptations to high-altitude aquatic environments. We have de novo assembled the genome of O. ascotanensis at high coverage. Comparative analysis of the O. ascotanensis genome showed an overall process of contraction, including loss of genes related to G-protein signaling, chemotaxis and signal transduction, while there was expansion of gene families associated with microtubule-based movement and protein ubiquitination. We identified 818 genes under positive selection, many of which are involved in DNA repair. Additionally, we identified novel and conserved microRNAs expressed in O. ascotanensis and its closely-related species, Orestias gloriae. Our analysis suggests that positive selection and expansion of genes that preserve genome stability are a potential adaptive mechanism to cope with the increased solar UV radiation to which high-altitude animals are exposed to.

Transcriptome analysis of the zebrafish atoh7-/- Mutant, lakritz, highlights Atoh7-dependent genetic networks with potential implications for human eye diseases.

Expression of the bHLH transcription protein Atoh7 is a crucial factor conferring competence to retinal progenitor cells for the development of retinal ganglion cells. Several studies have emerged establishing ATOH7 as a retinal disease gene. Remarkably, such studies uncovered ATOH7 variants associated with global eye defects including optic nerve hypoplasia, microphthalmia, retinal vascular disorders, and glaucoma. The complex genetic networks and cellular decisions arising downstream of atoh7 expression, and how their dysregulation cause development of such disease traits remains unknown. To begin to understand such Atoh7-dependent events in vivo, we performed transcriptome analysis of wild-type and atoh7 mutant (lakritz) zebrafish embryos at the onset of retinal ganglion cell differentiation. We investigated in silico interplays of atoh7 and other disease-related genes and pathways. By network reconstruction analysis of differentially expressed genes, we identified gene clusters enriched in retinal development, cell cycle, chromatin remodeling, stress response, and Wnt pathways. By weighted gene coexpression network, we identified coexpression modules affected by the mutation and enriched in retina development genes tightly connected to atoh7. We established the groundwork whereby Atoh7-linked cellular and molecular processes can be investigated in the dynamic multi-tissue environment of the developing normal and diseased vertebrate eye.

Genome Sequence of a Lactococcus lactis Strain Isolated from Salmonid Intestinal Microbiota.

Lactococcus lactis is a common inhabitant of the intestinal microbiota of salmonids, especially those in aquaculture systems. Here, we present a genome sequence of a Lactococcus lactis strain isolated from the intestinal contents of rainbow trout reared in Chile.

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)

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

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.

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.

Complete Genome Sequence of Vibrio anguillarum Phage CHOED Successfully Used for Phage Therapy in Aquaculture.

Vibrio anguillarum phage CHOED was isolated from Chilean mussels. It is a virulent phage showing effective inhibition of V. anguillarum. CHOED has potential in phage therapy, because it can protect fish from vibriosis in fish farms. Here, we announce the completely sequenced genome of V. anguillarum phage CHOED.