Organ xenotransplantation acceptance in veterinary students: A multicentric opinion study in Spain.

BACKGROUND: The shortage of available transplant organs has made it necessary to search for alternatives, one of which is xenotransplantation. However, the use of animal organs could face rejection from society and the personnel involved in its implementation. OBJECTIVES: (a) to analyze the attitudes of Veterinary Degree students in six Spanish Universities towards xenotransplantation; and (b) to determine the factors that affect its acceptance. METHODS: Of the 2815 students surveyed in the degree program, 2683 valid surveys were obtained. Attitudes towards organ xenotransplantation were evaluated using a validated questionnaire of organ donation. RESULTS: If xenotransplantation was confirmed as a clinical reality, 93% (n = 2493) of those surveyed would accept a xenotransplanted organ, whilst 7% would not. If the results of xenotransplantation were worse than those obtained with human donors and it entailed more risk, 12% (n = 318) would be in favor. 56% (n = 1497) of the students would accept a xenotransplantation provisionally pending the arrival of a human organ. Attitudes towards xenotransplantation were affected by the academic year in which a student was studying, with more favorable attitudes among students in the last year (88% in first year vs. 95% in fifth year; p < .001). More favorable attitudes are also observed depending on the attitude they have towards organ transplantation, with those students being more in favor of donating their organs when they die (94% vs. 88%; p < .001). CONCLUSION: Veterinary students would have a very favorable attitude toward xenotransplantation if these animal organs functioned as well as human organs. Therefore, these students could play an important role in the future promotion of this technique.

Kinetics of the invasion of a non-phagocytic fish cell line, RTG-2 by Yersinia ruckeri serotype O1 biotype 1.

Yersiniosis, caused by the fish pathogen Yersinia ruckeri, is a serious bacterial septicaemia affecting mainly salmonids worldwide. The acute infection may result in high mortality without apparent external disease signs, while the chronic one causes moderate to considerable mortality. Survivors of yersiniosis outbreaks become carriers. Y. ruckeri is able to adhere to, and to invade, phagocytic and non-phagocytic fish cells by using unknown molecular mechanisms. The aim of this study was to describe the kinetics of cell invasion by Y. ruckeri serotype O1 biotype 1 in a fish cell line (RTG-2) originating from rainbow trout gonads. The efficiency of invasion by Y. ruckeri was found to be temperature dependent, having a maximum at 20 °C. The bacterium was able to survive up to 96 h postinfection. The incubation of the cells at 4 °C and the pre-incubation of the bacteria with sugars or heat-inactivated antiserum significantly decreased the efficiency of invasion or even completely prevented the invasion of RTG-2 cells. These findings indicate that Y. ruckeri is capable of adhering to, entering and surviving within non-phagocytic cells, and that the intracellular environment may constitute a suitable niche for this pathogen that can favour the spread of infection and/or the maintenance of a carrier state of fish.

Tryptase is involved in the development of early ventilator-induced pulmonary fibrosis in sepsis-induced lung injury.

INTRODUCTION: Most patients with sepsis and acute lung injury require mechanical ventilation to improve oxygenation and facilitate organ repair. Mast cells are important in response to infection and resolution of tissue injury. Since tryptase secreted from mast cells has been associated with tissue fibrosis, we hypothesized that tryptase would be involved in the early development of ventilator-induced pulmonary fibrosis in a clinically relevant model of sepsis-induced lung injury. METHODS: Prospective, randomized, controlled animal study using Sprague-Dawley rats. Sepsis was induced by cecal ligation and perforation. Animals were randomized to spontaneous breathing or two ventilatory strategies for 4 h: protective ventilation with tidal volume (VT) = 6 ml/kg plus 10 cmH2O positive end-expiratory pressure (PEEP) or injurious ventilation with VT = 20 ml/kg plus 2 cmH2O PEEP. Healthy, non-ventilated animals served as non-septic controls. We studied the following end points: histology, serum cytokine levels, hydroxyproline content, tryptase and proteinase-activated receptor-2 (PAR-2) protein level in lung homogenates, and tryptase and PAR-2 immunohistochemical localization in the lungs. RESULTS: All septic animals developed acute lung injury. Animals ventilated with high VT had a significant increase of pulmonary fibrosis, hydroxyproline content, tryptase and PAR-2 protein levels compared to septic controls (P <0.0001). However, protective ventilation attenuated sepsis-induced lung injury and decreased lung tryptase and PAR-2 protein levels. Immunohistochemical staining confirmed the presence of tryptase and PAR-2 in the lungs. CONCLUSIONS: Mechanical ventilation modified tryptase and PAR-2 in injured lungs. Increased levels of these proteins were associated with development of sepsis and ventilator-induced pulmonary fibrosis early in the course of sepsis-induced lung injury.

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.

Haematological and biochemical blood reference values for Canary Island camels (Camelus dromedarius), an endangered dromedary species.

The purpose of this research was to develop reference values for haematological and biochemical variables in the Canary camel breed (Camelus dromedarius). 114 clinically healthy dromedary camels were assessed. Age, sex, and pregnancy status was also recorded. The reference range for red blood cells (RBCs) was 8.45 - 13.65 X106/µL, haemoglobin (HGB) was 10.61 - 15.29 g/dL, packed cell volume (PCV) was 19.93 - 32.51 %, and white blood cells (WBCs) 7.35 - 18.36 X103/µL. A correlation was established between the haemoglobin concentration (HGB) (g/dl) and packed cell volume (PCV) obtaining a linear regression (HGB = 0.31 PCV + 4.67). Young animals had higher RBC and WBC values than adult animals. Additionally, blood urea nitrogen (BUN), phosphorus, calcium, albumin/globulin (A/G) ratio, alkaline phosphatase, cholesterol, and lipase were higher in young animals compared with adults. Female dromedary camels showed higher values for the three main variables: RBC, HGB and PCV, but no differences between sexes were detected in the biochemical variables results. The WBC count was higher in non-pregnant females than in pregnant animals. These results provide references values for the Canary camel breed and may contribute to the understanding of differences in 18 haematological and biochemical parameters in dromedary camels with a potential impact in health and welfare for this species.

The Effect of Honey, Aloe Vera, and Hydrocolloid Dressing on the Healing Process of Murine Excisional Wounds.

Chronic ulcers are a major health problem associated with high costs and a loss of quality of life. Because of this, the search for products that accelerate wound healing is a constant, given the need for alternatives that help to alleviate this serious health problem. We analyzed the efficacy of 2 natural products-honey and aloe vera-versus hydrocolloid (HC) dressings as a control group in healing full-thickness wounds. For this purpose, we performed full-thickness excisions of the skin, including the panniculus carnosus, in mice. We inserted a nitrile ring into the subcutaneous cellular tissue simulating the second-intention wound healing course. We found that aloe vera reduced the diameter of the wounds compared to honey (p < .001) and the control group (p < .001).

Ciguatoxin Detection in Flesh and Liver of Relevant Fish Species from the Canary Islands.

The Canary Islands are a ciguatoxin (CTX) hotspot with an established official monitoring for the detection of CTX in fish flesh from the authorised points of first sale. Fish caught by recreational fishermen are not officially tested and the consumption of toxic viscera or flesh could lead to ciguatera poisoning (CP). The objectives of this study were to determine the presence of CTX-like toxicity in relevant species from this archipelago, compare CTX levels in liver and flesh and examine possible factors involved in their toxicity. Sixty amberjack (Seriola spp.), 27 dusky grouper (Epinephelus marginatus), 11 black moray eels (Muraena helena) and 11 common two-banded seabream (Diplodus vulgaris) were analysed by cell-based assay (CBA) and Caribbean ciguatoxin-1 (C-CTX1) was detected by liquid chromatography mass spectrometry (LC-MS/MS) in all these species. Most of the liver displayed higher CTX levels than flesh and even individuals without detectable CTX in flesh exhibited hepatic toxicity. Black moray eels stand out for the large difference between CTX concentration in both tissues. None of the specimens with non-toxic liver showed toxicity in flesh. This is the first evidence of the presence of C-CTX1 in the common two-banded seabream and the first report of toxicity comparison between liver and muscle from relevant fish species captured in the Canary Islands.

Screening of New Potential Probiotics Strains against Photobacterium damselae Subsp. piscicida for Marine Aquaculture.

On intensive fish farms, 10% of the population dies exclusively from pathogens, and Photobacterium damselae subsp. Piscicida (Ph. damselae subsp. Piscicida), the bacteria causing pasteurellosis in marine aquaculture, is one of the major pathogens involved. The objective of this study was to obtain new probiotic strains against pasteurellosis in order to limit the use of chemotherapy, avoiding the environmental repercussions generated by the abusive use of these products. In this study, 122 strains were isolated from the gills and intestines of different marine fish species and were later evaluated in vitro to demonstrate the production of antagonistic effects, the production of antibacterial substances, adhesion and growth to mucus, resistance to bile and resistance to pH gradients, as well as its harmlessness and the dynamic of expression of immune-related genes by real-time PCR after administration of the potential probiotic in the fish diet. Only 1/122 strains showed excellent results to be considered as a potential probiotic strain and continue its characterization against Ph. damselae subsp. piscicida to determine its protective effect and elucidating in future studies its use as a possible probiotic strain for marine aquaculture.

Study of histopathology on Arbacia lixula (Arbaciidae: Arbacioida) and Paracentrotus lividus (Parachinidae: Camarodonta) with bald sea urchin disease symptoms in Gran Canaria Island, Spain / Estudio de histopatología en Arbacia lixula (Arbaciidae: Arbacioida) y Paracentrotus lividus (Parachinidae: Camarodonta) con síntomas de la enfermedad del erizo desnudo en la Isla de Gran Canaria, España

Abstract Introduction: Sea urchin diseases have been documented in several locations worldwide, with reported occurrences of bacterial, protozoan, fungal, and algal infections. Objective: This study aimed to investigate pathogen agents in populations of Arbacia lixula and Paracentrotus lividus along the coast of Gran Canaria Island (Central-East Atlantic, Spain). Methods: Sampling was conducted at San Cristobal beach, on the Northeast side of the island, where sea urchins were manually collected from depths of 1-3 m during June, July, and October 2022. Swab samples were taken from the external and internal areas of the lesions and cultured on various media plates. Results: Eight different pathogen agents, including bacteria and fungi, were identified, with Vibrio alginolyticus being the most frequently observed bacteria in all diseased sea urchin samples. Additionally, ciliated protozoans were found within the tests, potentially acting as opportunistic parasites. Conclusions: This research provides a unique perspective on bald sea urchin disease by identifying a significant number of associated pathogens, including Candida, previously unreported in diseased organisms. Furthermore, the study highlights the presence of an inflammatory response in tissues with bacterial colonies, offering crucial insights into understanding this sea urchin disease.

Resumen Introducción: Las enfermedades en los erizos de mar han sido descritas en muchas localidades alrededor del mundo, y se han asociado con la presencia de infecciones por bacterias, protozoarios, hongos y algas. Objetivo: Este estudio tuvo como finalidad investigar sobre los agentes patógenos que afectan a las poblaciones de Arbacia lixula y Paracentrotus lividus a lo largo de la costa de la Isla de Gran Canaria (Atlántico Centro-Oriental, España). Métodos: El muestreo fue llevado a cabo en la playa de San Cristóbal, al noreste de la isla, dónde los organismos fueron capturados entre 1-3 metros de profundidad, durante junio, julio y octubre del año 2022. Se tomaron muestras en la zona interna y externa de la lesión en cada organismo, y se cultivaron en varios medios de cultivo. Resultados: Fueron identificados ocho agentes patógenos diferentes, incluyendo bacterias y hongos, y siendo Vibrio alginolyticus la bacteria más frecuentemente observada en todas las muestras de erizos enfermos. Además, se observaron protozoarios ciliados dentro de los caparazones, actuando potencialmente como parásitos oportunistas. Conclusiones: Esta investigación proporciona una perspectiva única sobre la enfermedad del erizo desnudo al identificar un número significativo de patógenos asociados, incluida Candida, que no se había reportado previamente en organismos enfermos. Además, el estudio destaca la presencia de una respuesta inflamatoria en tejidos con colonias bacterianas, lo que ofrece información crucial para comprender esta enfermedad de los erizos de mar.

Veterinary Spanish Students' Attitude Toward Presumed Consent in Organ Donation.

Veterinarians often are involved in transplantation research projects. They are a fundamental social group who can influence public opinion about organ donation and transplantation (ODT). OBJECTIVE: The objective was to determine the knowledge of Spanish veterinary students about the concept of brain death and the law of presumed consent. METHODS: A sociologic, multicenter, and observational study was carried out in the veterinary students enrolled in Spain (n = 9000) in a complete academic year. A sample of 2815 students was stratified by geographic area and academic year. The students' attitudes on the psychosocial aspects of ODT were evaluated using a psychosocial validated questionnaire (PCID-DTO Rios). It was self-administered and completed anonymously. Veterinary schools were randomly selected. The questionnaire was applied to each academic year at compulsory sessions. STATISTICAL ANALYSIS: Student t test, χ2 test, and logistic regression analysis were used. RESULTS: The completion rate was 91% (n = 2558). Of students, 66% (n = 1664) understood the concept of brain death, 30% had doubts, whereas 5% believed that a person with brain death can recover and lead a normal life. Concerning legislation, 63% (n = 1615) were against the law of presumed consent, and 37% were in favor. An analysis of variables determining more favorable acceptance of the law showed that year of study (P = .000), knowing a donor (P = .020), and attitude toward ODT (P = .000) did have an effect on acceptance. Most students, 71% (n = 1875), were interested in attending a talk about ODT. CONCLUSION: Only 37% of Spanish veterinary students would accept the law of presumed consent. Most students were interested in attending an informative talk about ODT.

Electrocardiographic changes in rats undergoing thoracic surgery under combined parenteral anesthesia.

To compare two protocols of combined parenteral general anesthesia, the authors analyzed electrocardiographic changes in anesthetized rats undergoing left pneumonectomy. One group of rats was anesthetized with a combination of medetomidine and ketamine (group 1, n = 10), and the other was injected with diazepam and ketamine (group 2, n = 10). Investigators obtained two electrocardiograms from each rat, one before surgery (5 min after anesthesia) and one after surgery (60 min after anesthesia). Anesthetic induction was quick for all rats, though four rats in group 2 died before surgery. Mean cardiac frequency and R-wave amplitude were significantly lower in rats in group 1 than in rats in group 2. Rats in group 1 received injections of atipamezole about 60 min after surgery, which reversed the effects of medetomidine; these rats regained voluntary respiratory movement more quickly than did rats in group 2. Two additional rats in group 2 died during postsurgical recovery. These results suggest that for thoracic surgery in rats, medetomidine-ketamine is an appropriate anesthetic combination, may be safer than diazepam-ketamine and yields a shorter recovery time.

Endotoxin-induced lung alveolar cell injury causes brain cell damage.

Sepsis is the most common cause of acute respiratory distress syndrome, a severe lung inflammatory disorder with an elevated morbidity and mortality. Sepsis and acute respiratory distress syndrome involve the release of inflammatory mediators to the systemic circulation, propagating the cellular and molecular response and affecting distal organs, including the brain. Since it has been reported that sepsis and acute respiratory distress syndrome contribute to brain dysfunction, we investigated the brain-lung crosstalk using a combined experimental in vitro airway epithelial and brain cell injury model. Conditioned medium collected from an in vitro lipopolysaccharide-induced airway epithelial cell injury model using human A549 alveolar cells was subsequently added at increasing concentrations (no conditioned, 2%, 5%, 10%, 15%, 25%, and 50%) to a rat mixed brain cell culture containing both astrocytes and neurons. Samples from culture media and cells from mixed brain cultures were collected before treatment, and at 6 and 24 h for analysis. Conditioned medium at 15% significantly increased apoptosis in brain cell cultures 24 h after treatment, whereas 25% and 50% significantly increased both necrosis and apoptosis. Levels of brain damage markers S100 calcium binding protein B and neuron-specific enolase, interleukin-6, macrophage inflammatory protein-2, as well as matrix metalloproteinase-9 increased significantly after treating brain cells with ≥2% conditioned medium. Our findings demonstrated that human epithelial pulmonary cells stimulated with bacterial lipopolysaccharide release inflammatory mediators that are able to induce a translational clinically relevant and harmful response in brain cells. These results support a brain-lung crosstalk during sepsis and sepsis-induced acute respiratory distress syndrome.

Multiple system organ response induced by hyperoxia in a clinically relevant animal model of sepsis.

Oxygen therapy is currently used as a supportive treatment in septic patients to improve tissue oxygenation. However, oxygen can exert deleterious effects on the inflammatory response triggered by infection. We postulated that the use of high oxygen concentrations may be partially responsible for the worsening of sepsis-induced multiple system organ dysfunction in an experimental clinically relevant model of sepsis. We used Sprague-Dawley rats. Sepsis was induced by cecal ligation and puncture. Sham-septic controls (n = 16) and septic animals (n = 32) were randomly assigned to four groups and placed in a sealed Plexiglas cage continuously flushed for 24 h with medical air (group 1), 40% oxygen (group 2), 60% oxygen (group 3), or 100% oxygen (group 4). We examined the effects of these oxygen concentrations on the spread of infection in blood, urine, peritoneal fluid, bronchoalveolar lavage, and meninges; serum levels of inflammatory biomarkers and reactive oxygen species production; and hematological parameters in all experimental groups. In cecal ligation and puncture animals, the use of higher oxygen concentrations was associated with a greater number of infected biological samples (P < 0.0001), higher serum levels of interleukin-6 (P < 0.0001), interleukin-10 (P = 0.033), and tumor necrosis factor-α (P = 0.034), a marked decrease in platelet counts (P < 0.001), and a marked elevation of reactive oxygen species serum levels (P = 0.0006) after 24 h of oxygen exposure. Oxygen therapy greatly influences the progression and clinical manifestation of multiple system organ dysfunction in experimental sepsis. If these results are extrapolated to humans, they suggest that oxygen therapy should be carefully managed in septic patients to minimize its deleterious effects.