Deciphering the gut microbiota of zebrafish, the most used fish as a biological model: A meta-analytic approach.

A meta-analytic approach deciphered the taxonomic profile of the zebrafish gut microbiota at different developmental stages. Data (16S rDNA) were systematically searched in databases, selecting those with intestine samples of fish not exposed to a particular treatment or challenge (e.g., pathogens, dietetic tests, xenobiotics, etc.) and obtaining 340 samples to be processed. Results revealed marked differences between the developmental phases. Proteobacteria was the dominant phylum in the larval phase, with a relative abundance of 90%, while the rest of the phyla did not exceed 2%. Vibrio, Aeromonas, Plesiomonas, Pseudomonas, Shewanella, and Acinetobacter were the dominant genera in this phase. Transitional changes were observed after the larvae stage. Proteobacteria still registered high abundance (48%) in the juvenile phase, but Fusobacteria (40%) and Bacteriodota (5.9%) registered considerable increases. Genera, including Cetobacterium, Plesiomonas, Aeromonas, Vibrio, and Flavobacterium, dominated this stage. The phyla Proteobacteria (48%) and Fusobacteria (35%) were strongly established in the adult phase. Cetobacterium was registered as the most abundant genus, followed by Aeromonas, Acinetobacter, Plesiomonas, Vibrio, and ZOR0006 (Firmicutes; 6%). In conclusion, the composition of the intestinal microbiota of zebrafish is consistently determined by two primary phyla, Proteobacteria and Fusobacteria; however, this composition varies depending on the developmental stage. Cetobacterium and Aeromonas are the most relevant genera in juveniles and adults. Finally, these results reveal a consistent pattern of certain bacterial groups in the zebrafish microbiota that could help shape gnotobiotic models (colonized with a specific known bacterial community) or synthetic microbiota (in vitro assembly of microbes), among other approaches.

Case Report: Ambergris coprolite and septicemia in a male sperm whale stranded in La Palma (Canary Islands).

On the 21st of May 2023, a dead adult male sperm whale (Physeter macrocephalus) of 13 m in length and estimated weight of around 18,000 kg was reportedly stranded at Playa Los Nogales, La Palma, Canary Islands, Spain. A necropsy was performed 48hpm. A 50 cm diameter and 9.5 kg coprolite was found obstructing the caudal colon-rectal lumen. Necro-hemorrhagic lesions were found in heart muscles and three different bacteria of intestinal origin were isolated and identified (Edwarsiella tarda, Hathewaya limosa and Clostridium perfringens). It is reported a lethal septicemia of intestinal origin associated with ambergris coprolite as cause of death in this sperm whale.

Volcanic tephra deposition dataset based on interpolated field measurements following the 2021 Tajogaite Eruption on La Palma, Canary Islands, Spain.

In 2021, the Tajogaite Volcano erupted along the western slope of the Cumbre Vieja on the island of La Palma, Canary Islands, Spain. Volcanic tephra blanketed a substantial proportion of the island. By our estimations, approximately 23,000,000 m3 of pyroclastic ashes and more coarse-grained particles were deposited unto La Palma's land surface in addition to the lava flow. Five months following the initial eruption, we measured the depth of the new ash layer across the island. We combined this data with drone-based observations to compile a dataset comprising the point distribution of ash depth. A spatial interpolation was then performed using Inverse Distance Weighting (IDW) to estimate the ash depth across the island at a 2 m spatial resolution. The interpolation performed well, yielding a root mean squared error (RMSE) value of 0.34 and thus, the dataset offers immense reuse potential for spatial inquiries related to evolutionary traits, vegetation patterns, and vegetation response to disturbance on oceanic islands. In addition, the data can be used to test different spatial interpolation techniques in an effort to improve the accuracy achieved using IDW.

Gastrointestinal dysbiosis induced by Nocardia sp. infection in tilapia.

Nocardiosis has caused high mortalities among fish cultures; however, the effects of Nocardia infections in the fish gastrointestinal microbiota are unknown. In this research, tilapia was infected with Nocardia sp., to analyze the effect of infection on the gastrointestinal microbiota. Tilapia infected with Nocardia sp. reported a 46 % survival (100 % in non-infected). Moreover, the infection caused severe damage to the stomach microbiota, with a loss of diversity and a significant increase of Proteobacteria (94.8 %), resulting in a negative correlation network between Proteobacteria and other important phyla. Nocardia sp. is an emerging pathogen capable of inducing dysbiosis and causing significant mortalities.

Microbiota plasticity in tilapia gut revealed by meta-analysis evaluating the effect of probiotics, prebiotics, and biofloc.

Tilapia species are among the most cultivated fish worldwide due to their biological advantages but face several challenges, including environmental impact and disease outbreaks. Feed additives, such as probiotics, prebiotics, and other microorganisms, have emerged as strategies to protect against pathogens and promote immune system activation and other host responses, with consequent reductions in antibiotic use. Because these additives also influence tilapia's gut microbiota and positively affect the tilapia culture, we assume it is a flexible annex organ capable of being subject to significant modifications without affecting the biological performance of the host. Therefore, we evaluated the effect of probiotics and other additives ingested by tilapia on its gut microbiota through a meta-analysis of several bioprojects studying the tilapia gut microbiota exposed to feed additives (probiotic, prebiotic, biofloc). A total of 221 tilapia gut microbiota samples from 14 bioprojects were evaluated. Alpha and beta diversity metrics showed no differentiation patterns in relation to the control group, either comparing additives as a group or individually. Results also revealed a control group with a wide dispersion pattern even when these fish did not receive additives. After concatenating the information, the tilapia gut core microbiota was represented by four enriched phyla including Proteobacteria (31%), Fusobacteria (23%), Actinobacteria (19%), and Firmicutes (16%), and seven minor phyla Planctomycetes (1%), Chlamydiae (1%), Chloroflexi (1%), Cyanobacteria (1%), Spirochaetes (1%), Deinococcus Thermus (1%), and Verrucomicrobia (1%). Finally, results suggest that the tilapia gut microbiota is a dynamic microbial community that can plastically respond to feed additives exposure with the potential to influence its taxonomic profile allowing a considerable optimal range of variation, probably guaranteeing its physiological function under different circumstances.

Long-term impact on cardiopulmonary function and quality of life among patients recovered from SARS-CoV-2 infection in a 6-month follow-up period in Lima, Peru: FUNCTION cohort study protocol.

INTRODUCTION: The sequelae of COVID-19 have been described as a multisystemic condition, with a great impact on the cardiovascular and pulmonary systems with abnormalities in pulmonary function tests, such as lower diffusing capacity of the lung for carbon monoxide (DLco) levels and pathological patterns in spirometry; persistence of radiological lesions; cardiac involvement such as myocarditis and pericarditis; and an increase in mental disorders such as anxiety and depression. Several factors, such as infection severity during the acute phase as well as vaccination status, have shown some variable effects on these post-COVID-19 conditions, mainly at a clinical level such as symptoms persistence. Longitudinal assessments and reversibility of changes across the spectrum of disease severity are required to understand the long-term impact of COVID-19. METHODS AND ANALYSIS: A prospective cohort study aims to assess the impact of SARS-CoV-2 infection on cardiopulmonary function and quality of life after the acute phase of the disease over a 6-month follow-up period. Sample size was calculated to recruit 200 participants with confirmatory COVID-19 tests who will be subsequently classified according to infection severity. Four follow-up visits at baseline, month 1, month 3 and month 6 after discharge from the acute phase of the infection will be scheduled as well as procedures such as spirometry, DLco test, 6-minute walk test, chest CT scan, echocardiogram, ECG, N-terminal pro-B-type natriuretic peptide measurement and RAND-36 scale. Primary outcomes are defined as abnormal pulmonary function test considered as DLco <80%, abnormal cardiovascular function considered as left ventricular ejection fraction <50% and abnormal quality of life considered as a <40 score for each sphere in the RAND-36-Item Short Form Health Survey. ETHICS AND DISSEMINATION: The study protocol was approved by the Institutional Ethics Committee of the Universidad Peruana Cayetano Heredia (SIDISI 203725) and the Ethics Committee of the Hospital Cayetano Heredia (042-2021). Protocol details were uploaded in ClinicalTrials.gov. Findings will be disseminated through peer-reviewed journals, scientific conferences and open-access social media platforms. TRIAL REGISTRATION NUMBER: NCT05386485.

Isolated left ventricular apical hypoplasia: case report.

Background: Isolated left ventricular apical hypoplasia (ILVAH) is a rare, probably congenital, cardiac condition recently reported in the last two decades. Although most cases are asymptomatic or mildly symptomatic, some severe and fatal cases have been reported, leading to more efforts for appropriate diagnosis and treatment. We describe the first, and severe, case of this pathology in Peru and Latin America. Case summary: A 24-year-old male with a history of long-standing alcohol and illicit drug use presented with symptoms of heart failure (HF) and atrial fibrillation (AF). Transthoracic echocardiography showed biventricular dysfunction along with spherical left ventricle, abnormal papillary muscles' origin from the left ventricular apex, and an elongated right ventricle wrapping around the deficient left ventricular apex. Cardiac magnetic resonance confirmed these findings and revealed subepicardial fatty replacement at the left ventricular apex. The diagnosis of ILVAH was made. He was discharged from hospital with carvedilol, enalapril, digoxin, and warfarin. Eighteen months later he remains mildly symptomatic at New York Heart Association functional class II without worsening HF nor thrombo-embolism. Discussion: This case highlights the usefulness of multimodality non-invasive cardiovascular imaging for accurate diagnosis of ILVAH as well as the importance of close follow-up and treatment of established complications (HF and AF).

Volcanic ash deposition as a selection mechanism towards woodiness.

The high proportion of woody plant species on oceanic islands has hitherto been explained mainly by gradual adaptation to climatic conditions. Here, we present a novel hypothesis that such woodiness is adaptative to volcanic ash (tephra) deposition. Oceanic islands are subject to frequent eruptions with substantial and widespread ash deposition on evolutionary time scales. We postulate that this selects for woodiness through an increased ability to avoid burial of plant organs by ash, and to re-emerge above the new land surface. We sense-checked using observations of plant occurrences and distributions on La Palma (Canary Islands) in April 2022, 4 months after the end of the eruptions of the Tajogaite volcano (Cumbre Vieja ridge). In contrast to herbs and grasses, most woody plants persisted and were already in full flower in areas with 10+ cm ash deposition. Remarkably, these persisting woody plants were almost exclusively endemics.

The fate of terrestrial biodiversity during an oceanic island volcanic eruption.

Volcanic activity provides a unique opportunity to study the ecological responses of organisms to catastrophic environmental destruction as an essential driver of biodiversity change on islands. However, despite this great scientific interest, no study of the biodiversity at an erupting volcano has yet been undertaken. On La Palma (Canary archipelago), we quantified the main species affected and their fate during the 85-day eruption (September-December 2021). Our main objective consisted of monitoring the biodiversity subjected to critical stress during this volcanic eruption. We found that all biodiversity within a 2.5 km radius was severely affected after the first two weeks. It is challenging to assess whether volcanism can drive evolutionary traits of insular organisms. Examples are the adaptation of an endemic conifer to high temperatures, selection of functional plant types-secondary woodiness-, effects of the disappearance of invertebrates and their influence in trophic nets and vertebrate trophic plasticity. However, our data suggest that such previous evolutionary changes might continue to favour their resilience during this eruption. Lastly, it is a very good opportunity to assess the extent to which these periodic volcanic catastrophes may constitute temporary windows of repeated opportunities for the evolution and speciation of oceanic island biota.

Seasonality of reproduction in wild cotton-top tamarins (Saguinus oedipus) in Colombia.

Seasonal availability of resources can influence the timing and success of reproduction in primates. This study examines the annual pattern of conceptions, mid-term (13 weeks) and full-term (26 weeks) pregnancy losses, births, and infant survivorship of the Critically Endangered cotton-top tamarin (Saguinus oedipus) at Proyecto Tití's long-term field site in Santa Catalina, Colombia. Using 18 years of behavior, physical exam, and fecal steroid data (N = 51 females, 168 conceptions, 121 liters), fecal estrone conjugate (E1 C) and pregnanediol-3-glucuronide (PdG) or progesterone (P4) profiles were examined to investigate the relationships between female reproductive patterns and reproductive success with feeding and climatic data. Cotton-top tamarins demonstrated seasonal patterns of reproduction and pregnancy losses. We found positive correlations between peak conception and nectarivory, births and rainfall, and mid-lactation and frugivory. High body mass mothers reproducing during the peak season were more likely to have infants survive. Overall, these results suggest that tamarins use a "relaxed income-breeder" strategy. Cotton-top tamarins appear to maximize reproductive output at the time of ovulation, and can reduce their investment in the current reproductive effort at many stages. Changes in food availability due to habitat loss and climate change will require the Critically Endangered cotton-top tamarins to alter their reproductive strategies to survive.

Physiological and antioxidant response of Litopenaeus vannamei against Vibrio parahaemolyticus infection after feeding supplemented diets containing Dunaliella sp. flour and ß-glucans.

The presence of pathogen agents in shrimp farming is the main obstacle for successful aquaculture. Vibrio species are naturally part of water because they play an important role as opportunistic bacteria. Vibrio parahaemolyticus was identified as the causative agent of the Early Mortality Syndrome in 2009, causing the loss of shrimp farming worldwide. Dunaliella sp. flour has been tested against Vibrio infection proving to be an effective prophylactic method that decreases mortality and improves physiological and immune response in Litopenaeus vannamei. Juvenile shrimp were exposed to 2% Dunaliella sp. flour and commercial 1.1% ß -glucan diet provided every other day for 15 days and a posterior infection with V. parahaemolyticus (1 × 106 CFU/mL). To evaluate shrimp stress status, some parameters as glucose, lactate, cholesterol, triglycerides, relative superoxide dismutase (SOD) gene expression and circulating hemocytes were analyzed in hemolymph at zero and seven days before infection and at 0, 24, and 48 h post-infection. L. vannamei fed with Dunaliella sp. showed 93% and ß -glucan 87% survival, compared with 79% in the infected control group. Additionally, Dunaliella sp. improved hemocyte and lipid concentrations compared to ß -glucan while both immunostimulants showed an increase in SOD response against bacteria. The addition of 2% Dunaliella sp. every other day in L. vannamei diet enhanced stress response against V. parahaemolyticus infection.

Type 2 diabetes mellitus in Peru: A literature review including studies at high-altitude settings.

We performed a comprehensive review of recent publications about type 2 diabetes mellitus (T2DM) in Peru, including studies among people living at high altitude above the sea level. An increase in the prevalence of T2DM in Peru has been reported, the reasons are multifactorial and coinciding with the strong economic growth that our country has experienced over the last 20 years along with migration from the Andean regions to the coast and the adoption of a lifestyle that is a known to be a risk factor for obesity and insulin resistance. Scarce information is available in Peru about the prevalence of chronic complications of T2DM such as retinopathy, neuropathy, and nephropathy. There is a need for a health care plan based on early diagnosis of T2DM to reduce social and economic problems, as recommended by the WHO and the United Nations.

Factors influencing the survival of wild cotton-top tamarin (Saguinus oedipus) infants.

Studies of cooperative breeding species have suggested that helpers are needed for infant survival and that helpers gain skills to successfully raise their own offspring. Studies of callitrichids in managed care and early field studies suggested that group size correlated with infant survival and that helpers needed to learn parental skills to be successful breeders. We present infant survival data from a 20-year field study of cotton-top tamarins (Saguinus oedipus) in Colombia involving 126 litters born to 41 females. There was no difference in the survival of male and female offspring to 6 months of age. However, litter size impacted survival, with triplet litters having lower survival and male triplets having lower survival than females. Loss of infants was highest in the first week of life and, of the animals remaining in the group at 6 months of age, 90% of them survived to 1 year. The mean length of time in the natal group was 2.3 years but some young migrated to other groups after 4 months of age. Group size and number of male helpers (>1 year) was not related to infant survival. However, groups with only one male had fewer surviving infants. Primiparous females had lower infant survival, but previous infant care experience by mothers as helpers had no effect on survival. A major cause of infant loss was group disruption due to deaths/evictions/loss of the reproductively active animals, or immigration of pregnant females. Thus, factors that cause a change in the stability of the reproductively active animals can disrupt group cohesion. Capture of individuals for the illegal pet trade, as well as habitat fragmentation, may increase competition between groups for access to territories and breeding opportunities. This may have long-term impacts to infant survival in this critically endangered species.

Violent encounter or capital punishment? Evidence of lethal violence in an indigenous burial from Fuerteventura (Canary Islands, Spain).

This paper focuses on an unusual Pre-Hispanic burial, 11-12th century cal AD, from Fuerteventura Island. The pattern of injuries of the skeletal remains, together with the grave's features suggest exceptional circumstances of death and funerary treatment differing from those commonly observed elsewhere among the indigenous population of the Canary Archipelago. The study first uses forensic anthropology techniques to characterise the individual's injuries before turning to archaeological and ethno-historical records of the indigenous populations to identify the potential scenarios explaining the fatal injuries. The nature of the peri-mortem lesions, especially those to the head, is consistent with an intention to kill. This case provides an opportunity to analyze the mechanisms of violence in a society with strong environmental limitations and conditions of isolation, as well as to deepen the concept of justice in ancient times.

Hypoxic hepatitis in an extensive aortic disecction: case report.

Hypoxic hepatitis is an uncommon cause of hepatic damage characterized by a centrolobular necrosis. Its pathophysiology remains unclear. Aortic dissection is a rare but frequently catastrophic event. It is caused by an aortic intimal tear with propagation of a false channel in the media. Depending on the site and extension, it can cause hypoperfusion of any organ leading to cellular ischemia and necrosis. We are presenting a case of hypoxic hepatitis in a patient with an extensive aortic dissection who present to the emergency department.

Hypoxic hepatitis in an extensive aortic disecction: case report / Hepatitis hipóxica en una disección aórtica extensa: reporte de caso

Hypoxic hepatitis is an uncommon cause of hepatic damage characterized by a centrolobular necrosis. Its pathophysiology remains unclear. Aortic dissection is a rare but frequently catastrophic event. It is caused by an aortic intimal tear with propagation of a false channel in the media. Depending on the site and extension, it can cause hypoperfusion of any organ leading to cellular ischemia and necrosis. We are presenting a case of hypoxic hepatitis in a patient with an extensive aortic dissection who present to the emergency department.

La hepatitis hipóxica es una causa poco frecuente de daño hepático caracterizada por una necrosis centrolobular. Su fisiopatología sigue siendo poco clara. La disección aórtica es un evento raro pero con frecuencia catastrófico. Dependiendo del sitio y la extensión, puede causar hipoperfusión de cualquier órgano lo que conduce a una isquemia celular y necrosis. Nosotros presentamos un caso de hepatitis hipóxica en un paciente con disección aórtica extensa que se presenta al servicio de emergencia.

Dosage and frequency effects of the microalgae Dunaliella sp. on the diet of Litopenaeus vannamei challenged with Vibrio parahaemolyticus.

Carotenoid sources in shrimp diets have shown to be effective for improving survival, growth, reproductive capacity, stress resistance, and also for diminishing disease. Dunaliella sp. is known to have high levels of ß-carotenes, which works as pro-vitamin A, enhancing the immune response in shrimp. However, the administration of Dunaliella sp. in shrimp diet needs to be evaluated to determine the appropriate dose and frequency of administration needed to optimize performance in cultured white shrimp. Diets with three different concentrations of Dunaliella sp. flour (1.5, 2 and 3%) were tested, and each one was administered at three different time frequencies: daily, and at 3- and 7-days intervals. Shrimp fed for 20 days were then infected with Vibrio parahaemolyticus (1 × 106 CFU/mL). Hemolymph parameters including protein, glucose, lactate, cholesterol and triglycerides were analyzed to evaluate shrimp stress status. Additionally, L. vannamei innate non-specific immune response was examined by evaluating the activity of prophenoloxidase (proPO), phenoloxidase (PO) and superoxide dismutase (SOD) in hemolymph; shrimp survival was also recorded. Survival after infection with V. parahaemolyticus was higher for shrimp fed with diets consisting of 2% Dunaliella sp. administered every 3 and 7 days. Shrimp fed a diet consisting of 2% or 3% Dunaliella sp. administered every third day showed positive physiological and immune responses to infection. A decrease in lipid oxidation in plasma triglycerides was observed at 48 h post inoculation in shrimp fed at all diets regimes due to Dunaliella sp. antioxidant action. Experimental results suggest the importance of Dunaliella sp. dosage and feeding frequency in L. vannamei diet to improve the survival and immune response.