Artículos Científicos

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Seroprevalencia de Besnoitia besnoiti, Coxiella burnetii y Chlamydia abortus en hatos bovinos lecheros de la zona norte de Costa Rica
(Universidad Nacional, Costa Rica, 2025) Fallas Elizondo, Daisy Elena; Jiménez Rocha, Ana Eugenia; Romero Zúñiga, Juan José; Dolz, Gaby
Besnoitia besnoiti y los agentes zoonóticos Coxiella burnetii y Chlamydia abortus ocasionan enfermedad reproductiva en bovinos. En Costa Rica no se cuenta con reportes de prevalencia de B. besnoiti y C. burnetii. El objetivo de este estudio fue determinar la seroprevalencia y distribución de estos tres agentes en fincas de lechería especializada y de doble propósito de la zona Huetar Norte de Costa Rica. Se realizó un estudio transversal descriptivo. Fueron estudiados 600 animales de 40 fincas (15 por finca), ubicadas en los distritos de Aguas Zarcas (5), Ciudad Quesada (9), Fortuna (4), Monterrey (2), Muelle (3), Venecia (5) y Zarcero (12). El análisis serológico se realizó mediante los ensayos inmunoenzimáticos comerciales de la compañía ID.VET (Montpellier, Francia). La seroprevalencia determinada para B. besnoiti fue alta (27,3%). Animales seropositivos se encontraron en un 80% de las fincas y en todos los distritos analizados, menos en la Fortuna, con las mayores prevalencias en Aguas Zarcas (64%), Venecia (36,6 %) y Zarcero (33,3 %). La seroprevalencia de C. burnetii fue 16,8 %, los animales positivos se encontraron en un 70 % de las fincas y distribuidos en todos los distritos, en especial Zarcero (24,6 %), Ciudad Quesada (19,2 %) y Aguas Zarcas (17,7 %). Con respecto a C. abortus, se determinó una seroprevalencia de 1,3 %, los animales seropositivos se encontraron solamente en un 17,5 % de fincas en tres distritos: Aguas Zarcas (3,3 %), Monterrey (3,3 %) y Ciudad Quesada (2,9 %). Se recomienda alertar a los grupos productores veterinarios y autoridades, para que tomen las medidas de prevención y control necesarias, en particular para C. burnetii y C. abortus, por su potencial zoonótico y realizar investigaciones para confirmar la presencia de estos agentes mediante aislamiento o diagnóstico molecular.
First report of Paragonimus mexicanus infection in a domestic cat from Costa Rica
(British Veterinary Association, 2026-01-06) Achi-Castro, Laura; García, Ricardo; Zúñiga-Moya, María; Dolz, Gaby; Arguedas, Randall
Paragonimus is the only genus in the family Troglotrematidae. Dogs, cats and other mammals may become infected by consuming crabs or shrimp harbouring metacercariae. A 1.11-year-old cat was presented with chronic coughing episodes. Thoracic radiography and ultrasonography suggested diffuse pneumonia. Cytology from a pulmonary granuloma and faecal examination revealed numerous trematode eggs (50–100 µm) consistent with Paragonimus spp. Molecular analysis of faecal DNA confirmed 100% nucleotide identity with Paragonimus mexicanus metacercariae previously reported from freshwater crabs in Puntarenas, Costa Rica. Antiparasitic therapy combining praziquantel, pyrantel and mebendazole resolved clinical signs. This case highlights the importance of including paragonimiasis in the differential diagnosis of cats with chronic respiratory disease in Central America, where aquatic intermediate hosts and wild reservoirs are abundant, even in peri-urban settings.
Combining RNAScope and RCA reveals a novel epitheliotropic bovine xipapillomavirus in udder papillomas
(Elsevier, 2025-11-01) Alfaro-Mora, Ramsés; ZOBBA, Rosanna; Cacciotto, Carla; ANTUOFERMO, Elisabetta; Pietro Burrai, Giovanni; Polinas, Marta; Rodríguez Barahona, Julia; Anfossi, Antonio; Dolz, Gaby; Alberti, Alberto
The diversity of papillomaviruses (PVs) remains largely unexplored, with many viral types still unidentified among mammalian hosts. Data on PV presence is particularly scarce in several regions of the world, including Central America. In this study, we report the identification and characterization of a novel Xipapillomavirus detected in udder papillomas from two dairy cows in Costa Rica. A combination of histopathology, RNA in situ hybridization (RNAScope), rolling circle amplification (RCA), and sequencing confirmed the viral presence, enabling genetic characterization and assessment of its cellular tropism. Based on our findings, we propose classifying this novel PV as a new type within the Bovine papillomavirus species, designated BPV45. Results revealed that BPV45 is an epitheliotropic virus closely related to BPV12 and belongs to the species Xipapillomavirus 1. Further research is needed to confirm the viral tropism for bovine udder tissue and to evaluate the potential economic impact on milk production and lactation performance.
Health assessment of Golden-Mantled Howler Monkeys (Alouatta Palliata Palliata) in dry forest from the North Pacific Coast, Costa Rica
(American Association of Zoo Veterinarians, 2025-03-14) Nodolf, Shannon B.; Smith, Joseph A.; Volle, Kurt A.; Bernal-Valle, Sofía; Dolz, Gaby; Russell, Mariah
The golden-mantled howler monkey (Alouatta palliata palliata) represents an excellent sentinel species for use in One Health modeling because of its extensive natural range, regular contact with humans and domestic animals, and susceptibility to zoonotic diseases. The purpose of this research is to establish baseline health assessments for free ranging golden-mantled howler monkeys in Marino Las Baulas National Park, Costa Rica. In April 2013, seven free ranging golden-mantled howler monkeys were anesthetized for physical examinations and biological sample collection, including blood for hematology and blood gas analysis. All seven howler monkeys studied appeared in good overall health. On physical exams, 4/7 (57%) had some level of dental disease, most notably crown fractures. Fecal samples for endoparasite evaluation were collected from the seven anesthetized animals as well as an additional three animals that were anesthetized but remained in the trees out of reach for full physical exams. Feces were collected from the rectum or collected from the ground immediately after defecation. Fecal analysis showed 9/10 (90%) had one or more species of intestinal parasites, and one animal tested positive for Giardia spp. Hematologic values showed a mild monocytosis and eosinophilia compared to other Alouatta spp. Trypanosoma spp. were present in the blood smear of one animal. Additional vector-borne disease testing found one individual PCR positive to Plasmodium spp., and one individual PCR positive to Venezuelan equine encephalitis virus. Antibodies for West Nile virus were found in 5/7 (71%) of the animals; however, PCR testing for West Nile virus and dengue virus was negative for all samples. This represents the first published health assessments for howler monkeys in this region.
Serosurvey of Arboviruses in Free-Ranging Mantled Howler Monkeys (Alouatta palliata) in Costa Rica
(Wildlife Disease Association, 2025-02-03) Larsen, R Scott; Moresco, Anneke; Karabatsos, Nick; Dolz, Gaby; Glander, Kenneth E.
We investigated the prevalence of arthropod-borne viral diseases in a population of free-ranging mantled howler monkeys (Alouatta palliata) in Costa Rica in 1998. Blood samples were opportunistically collected from monkeys anesthetized for another study. Serology was performed on 64 individuals to assess exposure of this population to vesicular stomatitis virus, equine encephalitis viruses, Mayaro virus, St. Louis encephalitis virus, yellow fever virus, and dengue virus. The New Jersey serotype of vesicular stomatitis (VSV-NJ) was the only pathogen for which the population tested positive (44% [28/64]). This is the first report of antibodies against VSV-NJ in nonhuman primates in Costa Rica.
Identification of Paragonimus mexicanus and P. caliensis in freshwater crabs from Costa Rica: evidence of zoonotic lung fluke diversity in Central America
(PLOS Neglected Tropical Diseases, 2026-01-13) Wehrtmann, Ingo S.; Hernández-Chea, Roderico; Magalhães, Célio; Dolz, Gaby; Zuniga Moya, María José; Romero-Chaves, Raquel; Villalobos-Rojas, Fresia
Paragonimus spp. are foodborne trematodes with complex life cycles involving freshwater snails and decapod crustaceans. In Central America, Paragonimus mexicanus is a known zoonotic agent, whereas the public health significance of P. caliensis remains unclear. Between 2015 and 2016, we surveyed freshwater crabs across 51 sites in 15 river basins spanning three major climatic regions in Costa Rica. A total of 419 crabs (10 species) were examined for metacercariae; male crabs were identified morphologically, and infected females were identified to species by 16S rRNA and COI sequencing. Metacercariae were detected in six crab species, three of which represent new hosts of Paragonimus. The highest prevalence in male crabs occurred in Ptychophallus uncinatus (55.6%, 25/45). Molecular analyses confirmed the presence of two Paragonimus species in crabs: P. mexicanus and P. caliensis. A binomial GLM showed that males had higher odds of infection than females (p = 0.0059). Most infections occurred in areas along the Caribbean coast and in the Northern Region, which drains into Lake Nicaragua and Río San Juan. A binomial GLM revealed that the probability of Paragonimus infection varied significantly across climatic regions. Crabs from the Caribbean slope had the highest odds of infection, followed by the Northern Region. In contrast, crabs from the Pacific slope were significantly less likely to be infected. These patterns support the existence of geographic clusters of transmission within Costa Rica. We provide the first species-level, molecular confirmation of infected female crabs in Costa Rica and identify three freshwater crab species as newly recognized second intermediate hosts. These findings expand the known host range and distribution of Paragonimus in Costa Rica and highlight the need for public health education about the risks of consuming undercooked freshwater crabs.
Molecular detection of vector-borne and hemotropic pathogens in raccoons (Procyon lotor) from a tropical ecotourism area in Costa Rica
(Elsevier Ltd on behalf of Australian Society for Parasitology, 2026-01-03) Calderon-Bailey, Jennifer; Rojas-Sanchez, Ernesto; Mata-Masís, María; Jiménez-Soto, Mauricio; Solorzano-Morales, Antony; Zúñiga-Moya, María José; Varela-Amador, Javier; Vega-Benavides, Karen; Dolz, Gaby
Interactions between wildlife, domestic animals, and humans in ecotourism settings could facilitate the circulation of pathogens with zoonotic potential. Raccoons Procyon lotor), due to their synanthropic behavior and adaptability, may serve as hosts for several infectious agents at these interfaces. This study aimed to investigate the presence of vector-borne and hemotropic pathogens in free-ranging raccoons inhabiting Manuel Antonio National Park (MANP) and its surrounding communities, a major tourist destination in Costa Rica. Between 2021 and 2022, nineteen raccoons were captured using Tomahawk traps, anesthetized, clinically examined, and sampled for hematological and molecular analyses. DNA extracted from blood was screened using real-time and conventional PCR assays targeting Anaplasma spp., Ehrlichia spp., Rickettsia spp., Trypanosoma spp., Mycoplasma spp., and canine protoparvovirus 1 (CPPV-1). Of the individuals tested, 6/19 (31.6 %) were positive for Anaplasmataceae, 4/14 (28.6 %) for Mycoplasma spp., and 6/14 (42.9 %) for CPPV-1. One raccoon was confirmed to carry Mycoplasma haemocanis (99 % nucleotide identity with GenBank accession MN294708), representing the first molecular identification of this species in raccoons worldwide. Coinfections were detected in five animals. No raccoons tested positive for Rickettsia spp. or Trypanosoma spp. Hematological profiles were largely within reference ranges; however, mild leukogram variations and occasional hyperglobulinemia were observed, with no consistent infection-associated pattern. These findings provide molecular evidence of pathogen presence in raccoons from a high-tourism area and highlight their potential epidemiological relevance at the wildlife-human interface. The results underscore the need for sustained One Health surveillance to better assess pathogen transmission risks in tropical ecotourism settings.
Nutrition management, nitrogen efficiency, and income over feed cost on dairy farms in Costa Rica
(American Dairy Science Association, 1998) Baars, R. M. T.
Twenty-two dairy farms in two ecologically different zones were visited repeatedly during the dry and wet seasons of 1995 to evaluate nutrition and pasture management, N efficiency on the farm, and income over feed costs with the use of a management support program. Excessive amounts of concentrates were fed, and no differences in amounts were detected between seasons. Utilization of forage was consequently low and even negligible on some farms. The amount of crude protein in the diet was generally too high. The removal of N from the farms via milk and culling represented 27 and 31% of the total N input for the two regions, respectively. The income over feed costs per cow ($3.04 and $1.84/d, respectively) was considered reasonable despite the high amount of concentrates.
Mannose-resistant hemagglutination, enzyme-linked immunosorbent assay, and immune electron microscopy for detection of k99 fimbrial antigen in escherichia coli from calves
(American Society for Microbiology, 1989) Hernández, Francisco; Caballero, Magaly; Rivera, Patricia
Mannose-resistant hemagglutination (MRHA) was evaluated for identification of Escherichia coli with K99 fimbriae. The sensitivity and specificity of MRHA, relative to the enzyme-linked immunosorbent assay, were 21 and 79%v, respectively. Disagreement between the tests may have been due in part to separation of pili from the ceUls, with resultant enzyme-linked immunosorbent assay-positive, MRHA-negative tests. MRHA was not useful as the sole means for the identification of E. coli with K99 fimbriae.
Immunodiffusion test for serodiagnosing subcutaneous zygomycosis
(American Society for Microbiology, 1990-09) Kaufman, Leo; Mendoza, Leonel; Standard, Paul G.
Los antígenos de filtrado de cultivo de Basidiobolus ranarum y Conidiobolus coronatus se analizaron por inmunodifusión (ID) con antisueros homólogos de conejo. Se encontró que B. ranarum y C. coronatus tenían cinco antígenos específicos cada uno. Los resultados de las pruebas con antisueros heterólogos indicaron que todas las especies compartían al menos un antígeno. Se desarrollaron pruebas de ID que incorporan las bandas de precipitina específicas como referencias para la detección de basidiobolomicosis y conidiobolomicosis. Estas pruebas se realizaron con sueros de humanos y caballos con basidiobolomicosis y conidiobolomicosis comprobadas, así como con sueros de control de humanos y animales con y sin infecciones micóticas y oomicóticas heterólogas. Solo los sueros de casos de basidiobolomicosis y conidiobolomicosis produjeron líneas de identidad con los precipitados de referencia de B. ranarum y C. coronatus, respectivamente. Se encontró que las pruebas de ID eran completamente sensibles y específicas para determinar la etiología de la zigomicosis causada por estas dos especies. Además, resultaron útiles para supervisar la resolución de las infecciones.
Rapid detection of vesicular stomatitis virus New Jersey serotype in clinical samples by using polymerase chain reaction
(American Society for Microbiology, 1993) Rodriguez, Luis L.; Letchworth, Geoffrey J; Spiropoulou, Christina F.; Nichol, Stuart T.
El virus de la estomatitis vesicular del serotipo Nueva Jersey (VSV-NJ) causa enfermedad vesicular en bovinos, cerdos y caballos en todo el continente americano. La enfermedad vesicular es clínicamente indistinguible de la fiebre aftosa (FA). Por lo tanto, los brotes de enfermedad vesicular en zonas libres de FA deben diagnosticarse rápidamente mediante métodos de laboratorio y las granjas afectadas deben permanecer en cuarentena hasta que los resultados de laboratorio confirmen la ausencia de FA. El diagnóstico se realiza actualmente en laboratorios de alta contención (nivel 3 de bioseguridad) mediante fijación del complemento y aislamiento del virus en cultivo de tejidos. Describimos aquí un método alternativo para la detección del ARN del VSV-NJ en muestras clínicas. Este método incluye un procedimiento rápido de extracción de ARN con guanidina-fenol ácido, junto con una reacción en cadena de la polimerasa (PCR) en un solo tubo con transcriptasa inversa. Mediante esta prueba, pudimos detectar el mayor número de muestras positivas (53 de 58), seguidas de la detección del complemento (48 de 58) y el aislamiento en cultivo de tejidos (43 de 58). Los cebadores seleccionados para este ensayo amplifican una región de 642 nucleótidos del gen de la fosfoproteína de VSV-NJ, pero no de VSV-IN. La secuenciación del producto de PCR permite la tipificación genética de aislados virales y estudios epidemiológicos. Dado que no se requieren materiales infecciosos para realizar esta prueba y que cualquier virus infeccioso presente en muestras clínicas se destruye mediante el tratamiento con guanidina ácida-fenol, el diagnóstico puede realizarse con seguridad en laboratorios de diagnóstico convencionales.
Detection of bovine trichomoniasis with a specific dna Probe and PCR amplification system
(American Society for Microbiology, 1994) Ho, Michael S. Y.; Conrad, Patricia A.; Conrad, Phillip J.; Lefebvre, Rance B.; Perez, Enrique; Bondurante, Roberto H.
Trichomoniasis is a widespread, economically important venereal disease of cattle which causes infertility and abortion. Effective control of trichomoniasis has been impeded by the insensitivity of traditional diagnostic procedures, which require the isolation and cultivation of the parasite, 7Titrichomonasfoetus, from infected cattle. We developed a 0.85-kb T.foetus DNA probe by identifying conserved sequences in DNAs from T.foetus that were isolated from cattle in California, Idaho, Nevada, and Costa Rica. The probe hybridized specifically to DNAs of T. foetus isolates from different geographic areas but not to DNA preparations of Trichomonas vaginalis, bovine cells, or a variety of bacteria from cattle. The probe detected DNA from a minimum of i05 T. foetus organisms. To improve sensitivity, a partial sequence of the probe was used to identify oligonucleotide primers (TF1 and TF2) which could be used to amplify a 162-bp product from T. foetus DNAs by PCR. A chemiluminescent internal T. foetus sequence probe was hybridized to Southern blots of the amplification product. This system detected as few as one T. foetus organism in culture media or 10 parasites in samples containing bovine preputial smegma. Analysis of 52 clinical samples showed that 47 (90.4%) of the 52 samples were correctly identified, with no false-positive reactions. In comparison, the traditional cultivation method detected 44 (84.6%) of the 52 samples from T. foetus-infected and uninfected bulls. These results indicate that the PCR-based amplification system could be a useful alternative method for the diagnosis of bovine trichomoniasis.
Brucella abortus 16s rRNA and lipid a reveal a phylogenetic relationship with members of the Alpha-2 subdivision of the class proteobacteria
(American Society for Microbiology, 1990-07) Moreno, Edgardo; Stackebrandt, Erko; Dorsch, Matthias; Wolters, Jörn; Mayer, Hubert; Busch, Michael
On the basis of ribosomal 16S sequence comparison, Brucella abortus has been found to be a member of the alpha-2 subdivision of the class Proteobacteria (formerly named purple photosynthetic bacteria and their nonphototrophic relatives). Within the alpha-2 subgroup, brucellae are specifically related to rickettsiae, agrobacteria, and rhizobiae, organisms that also have the faculty or the obligation of living in close association to eucaryotic cells. The composition of Brucella lipid A suggests a close phylogenetical relationship with members of the alpha-2 group. The chemical analysis of the lipid A fraction revealed that Brucella species contain both glucosamine and diaminoglucose, thus suggesting the presence of a so-called mixed lipid A type. The serological analysis with polyclonal and monoclonal antibodies is in agreement with the existence of mixe lipid A type in B. abortus. The amide-linked fatty acid present as acyl-oxyacyl residues were 3-O-C(16:o)l2:0o 3-O-C(16:o)l3:0o 3O0 C(16:o)l4:O0 and 3-0-C(l8:O)l4:O. The only amide-linked unsubstituted fatty acid detected was 3-OH-C16:0O The ester-linked fatty acids are 3-OH-C16:0, 3-OH-C18:0, C16:0, C17:0, and C18:0. Significant amounts of the large-chain 27-OH-C28: were detected together with traces of 25-OH-C26:0 and 29-OH-C30:0. Comparison of the Brucella lipid composition with that of the other Proteobacteria also suggests a close phylogenetical relationship with members of the alpha-2 subdivision. The genealogical grouping of Brucella species with pericellular and intracellular plant and animal pathogens as well as with intracellular plant symbionts suggests a possible evolution of Brucella species from plant-arthropod-associated bacteria.
Human ascariasis, an evolutionary complex relationship between host and parasite
(Universidad Nacional, Costa Rica, 2022) Baldi, Mario; Baldi, Norberto
Ascariasis is a debilitating parasitic disease that has decimated the health of hundreds of thousands of human beings, especially in developing countries. The lack of adequate prophylaxis of the parasite associated with an increased risk of immunological disease is a challenge mainly in developed countries where the prevalence of this parasite is very low. The evolutionary relationship and mechanisms by which the parasite was able to colonize and establish itself in human hosts have not yet been unraveled. In addition, the host immune response mechanisms to eliminate or control the parasite are not fully understood. Understanding these immunological mechanisms (proximates) will allow establishing better medical treatments for diseases related to the positive effects of parasitosis, thus also avoiding the undesirable effects of the parasitosis itself.
Anatomical and radiographic study on the appendicular skeleton of the Tamandua mexicana
(Universidad Nacional, Costa Rica, 2022-01) Calvo Varela, Ariana; Hernández Valerio, Mauren; Villalobos Morales, Dominique; Fernández Mesén, Alison; Alpizar Moreno, Katherina; Salas Zamora, Dennis; Miranda Fernández, Daniel; Chaverri Esquivel, Laura; Passos Pequeno, Andréia
Tamandua mexicana species has an important role in the natural ecosystem as a pest controller, feeding on insects such as termites. One of the main anatomical adaptations that this species has undergone has been to its thoracic extremities. Having detailed knowledge regarding the osteology of the thoracic limbs of T. mexicana provides a strong base for its application in clinical-surgical practice. In addition to collaborating with the greater understanding of animal physiology and behavior. Because there was a lack of description about the appendicular skeleton anatomy of this species, the objective of this investigation was to describe the osteology and the radiographic anatomy of the appendicular skeleton of the T. mexicana. The bones used belonging to the appendicular skeleton of two specimens of T. mexicana were properly cleaned using standard boiling and maceration techniques. The morphometry of the bones was performed using a measuring tape, pachymeter, and radiographies. With this study, it was possible to identify and describe the anatomical peculiarities such as the presence of the double scapular spine that shapes the caudolateral fossa, and at the end of the humerus, the supratrochlear foramen, in addition to a markedly prominent medial epicondyle. In addition, a difference was observed between metacarpal bones and the phalanges of the third digit compared to the other ones, as it is significantly thicker. These findings reinforced the evidence that a certain degree of anatomical specialization is a result of an adaptation of this species to its environment and diet. The knowledge provided by research like this contributes to the improvement of surgical techniques and diagnostic approach in the species.
The lipopolysaccharide of brucella abortus BVRS/BVRR mutants contains lipid a modifications and has higher affinity for bactericidal cationic peptides
(American Society for Microbiology, 2005-08) Manterola, Lorea; Moriyón, Ignacio; Moreno, Edgardo; Sola-Landa, Alberto; Weiss, David S.; Koch, Michel H. J.; Howe, Jörg; Brandenburg, Klaus; López-Goñil, Ignacio
The two-component BvrS/BvrR system is essential for Brucella abortus virulence. It was shown previously that its dysfunction abrogates expression of some major outer membrane proteins and increases bactericidal peptide sensitivity. Here, we report that BvrS/BvrR mutants have increased surface hydrophobicity and susceptibility to killing by nonimmune serum. The bvrS and bvrR mutant lipopolysaccharides (LPSs) bound more polymyxin B, chimeras constructed with bvrS mutant cells and parental LPS showed augmented polymyxin B resistance, and, conversely, parental cells and bvrS mutant LPS chimeras were more sensitive and displayed polymyxin B-characteristic outer membrane lesions, implicating LPS as being responsible for the phenotype of the BvrS/BvrR mutants. No qualitative or quantitative changes were detected in other envelope and outer membrane components examined: periplasmic (1-2) glucans, native hapten polysaccharide, and phospholipids. The LPS of the mutants was similar to parental LPS in O-polysaccharide polymerization and fine structure but showed both increased underacylated lipid A species and higher acyl-chain fluidity that correlated with polymyxin B binding. These lipid A changes did not alter LPS cytokine induction, showing that in contrast to other gram-negative pathogens, recognition by innate immune receptors is not decreased by these changes in LPS structure. Transcription of Brucella genes required for incorporating long acyl chains into lipid A (acpXL and lpxXL) or implicated in lipid A acylation control (bacA) was not affected. We propose that in Brucella the outer membrane homeostasis depends on the functioning of BvrS/BvrR. Accordingly, disruption of BvrS/BvrR damages the outer membrane, thus contributing to the severe attenuation manifested by bvrS and bvrR mutants.
Some digenetic trematodes of the olive ridley sea turtle, Lepidochelys olivacea (Testudines, Cheloniidae) in Costa Rica
(Parasitological Institute of SAS, 2007-01) Santoro, M.; Morales, Juan Alberto
Se recuperaron tres especies de digeneos, incluyendo un gorgoderidae (Plesiochorus cymbiformis) de la vejiga urinaria, un plagiorchiidae (Enodiotrema megachondrus) del duodeno y un pachypsolidae (Pachypsolus irroratus) del estómago, de dos de tres tortugas golfinas (Lepidochelys olivacea) varadas a lo largo de la costa del Pacífico de Costa Rica. Todos los trematodos representan nuevos registros de localidad. Se describieron cambios histopatológicos asociados con huevos de duelas cardiovasculares (Digenea, Spirorchiidae) en los pulmones, el bazo y el intestino de una sola tortuga.
Redescription of Charaxicephaloides polyorchis Groschaft and Tenora 1978 (Digenea: Pronocephalidae) from the green turtle Chelonia mydas in Costa Rica
(Parasitological Institute of SAS, 2009-06-20) Santoro, M.; Brandmayr, P.; Greiner, E.; Morales, Juan Alberto; Rodríguez-Ortíz, B.
Charaxicephaloides polyorchis (Groschaft y Tenora, 1978) se reescribe con base en especímenes recolectados del estómago de tortugas verdes Chelonia mydas en Costa Rica. Nuestros especímenes coinciden con la descripción original, basada en cuatro aletas caudales de la misma especie hospedadora de la costa noroeste de Cuba. Nuestra redescripción proporciona una nueva gama de variaciones y aporta nueva información sobre esta especie. Este es solo el segundo registro de C. polyorchis en tortugas verdes.
Tyr→Trp-substituted peptide 115-129 of a Lys49 phospholipase A2 expresses enhanced membrane-damaging activities and reproduces its in vivo myotoxic effect
(Elsevier B.V., 1999-11-09) Lomonte, Bruno; Pizarro-Cerda, Javier; Angulo, Yamileth; Gorvel, Jean-Pierre; Moreno, Edgardo
Myotoxin II is a group II Lys49 phospholipase A2 (PLA2) isolated from the venom of the snake Bothrops asper. Previous studies on a synthetic peptide derived from its heparin-binding, cationic/hydrophobic sequence 115^129 demonstrated a direct functional role of this particular region in the in vitro cytolytic and bactericidal actions of the protein. Nevertheless, no significant myonecrosis has been observed after local intramuscular injection of peptide 115-129 (p115-129) in mice. Since the membrane-damaging action of p115-129 was proposed to depend on its amphiphilic character, the present study examined the effects of substituting its cluster of three tyrosine residues by tryptophan residues, on its toxic/pharmacological activities in vitro and in vivo. This substitution resulted in a drastic enhancement of the membrane-damaging activities of the peptide (p115-W3), together with the clear expression of myotoxic activity in vivo. Both the heparin-binding and antigenic characteristics of p115-129 were essentially conserved in p115-W3, suggesting that the modification did not lead to radical structural alterations. In addition to myotoxicity, cytotoxicity, and bactericidal action, p115-W3 exerted edema-forming activity in the mouse footpad assay. Thus, the synthetic 13-mer p115-W3 reproduced all the known toxic effects of myotoxin II. In spite of its potent membrane-damaging actions, p115-W3 did not acquire direct hemolytic activity upon mouse erythrocytes, an effect which is not present in myotoxin II, but that has been ascribed to the presence of tryptophan in other cationic, membrane-damaging peptides such as mellitin from bee venom. The myotoxic activity of p115-W3 herein described constitutes the first example of a short, PLA2-based linear synthetic peptide with the ability to reproduce this effect of a parent protein in vivo. This finding is in clear support of the proposed relevance of the C-terminal region 115^129 in all the membrane-damaging mechanisms exerted by myotoxin II, including the myotoxic mechanism.
Objective evaluation of the response to perineural analgesia of the deep branch of the lateral plantar nerve and intraarticular analgesia of the tarsometatarsal joint in horses with suspected proximal metatarsal pain using body-mounted inertial sensors
(Elsevier Inc., 2018) LEELAMANKONG, P.; Estrada McDermott, Roberto J.; Rungsri, Porrakote; Wolfgang, Stäcker; Müller, Carolin D.V.S; Lischer, Christoph
Perineural analgesia of the deep branch of the lateral plantar nerve (DBLPN block) and intraarticular analgesia of the tarsometatarsal joint (TMT block) are commonly used to differentiate pain originating from the distal tarsal and the proximal metatarsal areas in horses. However, both analgesic techniques have recently been subjected to close scrutiny, with questions raised as to their efficacy. The purpose of this study is to undertake an objective assessment of the effect of both diagnostic analgesia techniques on hindlimb lameness using a body-mounted inertial sensor system (Lameness Locator; Equinosis LLC, Columbia, MO). Horses with chronic hindlimb lameness were instrumented with inertial sensors measuring vertical pelvic asymmetry in millimeters and underwent a routine lameness examination including diagnostic analgesia. Twenty-seven horses showing an improvement in lameness after the DBLPN block were selected for the study. These horses underwent the TMT block on the following day. The change in vertical pelvic asymmetry after the DBLPN block was compared to the change following the TMT block. Of 27 horses, 17 showed improvement after the DBLPN block but not after the TMT block (group 1). The other 10 horses showed improvement in lameness after both analgesic techniques (group 2). The DBLPN block and the TMT block desensitized different structures in more than half of the horses. However, the possibility that both analgesic techniques can desensitize the same structures due to either the diffusion of the anesthetic agent or of an inadvertent injection still remains.

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