59 research outputs found
Genetic and Phenotypic Characterization of the Etiological Agent of Canine Orchiepididymitis Smooth Brucella sp. BCCN84.3
Members of the genus Brucella cluster in two phylogenetic groups: classical and non-classical species. The former group is composed of Brucella species that cause disease in mammals, including humans. A Brucella species, labeled as Brucella sp. BCCN84.3, was isolated from the testes of a Saint Bernard dog suffering orchiepididymitis, in Costa Rica. Following standard microbiological methods, the bacterium was first defined as "Brucella melitensis biovar 2." Further molecular typing, identified the strain as an atypical "Brucella suis." Distinctive Brucella sp. BCCN84.3 markers, absent in other Brucella species and strains, were revealed by fatty acid methyl ester analysis, high resolution melting PCR and omp25 and omp2a/omp2b gene diversity. Analysis of multiple loci variable number of tandem repeats and whole genome sequencing demonstrated that this isolate was different from the currently described Brucella species. The smooth Brucella sp. BCCN84.3 clusters together with the classical Brucella Glade and displays all the genes required for virulence. Brucella sp. BCCN84.3 is a species nova taxonomical entity displaying pathogenicity; therefore, relevant for differential diagnoses in the context of brucellosis. Considering the debate on the Brucella species concept, there is a need to describe the extant taxonomical entities of these pathogens in order to understand the dispersion and evolution
Virulent Brucella nosferati infecting Desmodus rotundus has emerging potential due to the broad foraging range of its bat host for humans and wild and domestic animals
Desmodus rotundus, vampire bats, transmit dangerous infections, and brucellosis is a hazardous zoonotic disease, two adversities that coexist in the subtropical and tropical areas of the American continent. Here, we report a 47.89% Brucella infection prevalence in a colony of vampire bats inhabiting the tropical rainforest of Costa Rica. The bacterium induced placentitis and fetal death in bats. Wide-range phenotypic and genotypic characterization placed the Brucella organisms as a new pathogenic species named Brucella nosferati sp. nov., isolated from bat tissues, including the salivary glands, suggesting feeding behavior might favor transmission to their prey. Overall analyses placed B. nosferati as the etiological agent of a reported canine brucellosis case, demonstrating its potential for infecting other hosts. To assess the putative prey hosts, we analyzed the intestinal contents of 14 infected and 23 non-infected bats by proteomics. A total of 54,508 peptides sorted into 7,203 unique peptides corresponding to 1,521 proteins were identified. Twenty-three wildlife and domestic taxa, including humans, were foraged by B. nosferati-infected D. rotundus, suggesting contact of this bacterium with a broad range of hosts. Our approach is appropriate for detecting, in a single study, the prey preferences of vampire bats in a diverse area, demonstrating its suitability for control strategies where vampire bats thrive.
IMPORTANCE: The discovery that a high proportion of vampire bats in a tropical area is infected with pathogenic Brucella nosferati and that bats forage on humans and many wild and domestic animals is relevant from the perspective of emerging disease prevention. Indeed, bats harboring B. nosferati in their salivary glands may transmit this pathogenic bacterium to other hosts. This potential is not trivial since, besides the demonstrated pathogenicity, this bacterium possesses all the required virulent arsenal of dangerous Brucella organisms, including those that are zoonotic for humans. Our work has settled the basis for future surveillance actions in brucellosis control programs where these infected bats thrive. Moreover, our strategy to identify the foraging range of bats may be adapted for exploring the feeding habits of diverse animals, including arthropod vectors of infectious diseases, and therefore of interest to a broader audience besides experts on Brucella and bats. The discovery that a high proportion of vampire bats in a tropical area is infected with pathogenic Brucella nosferati and that bats forage on humans and many wild and domestic animals is relevant from the perspective of emerging disease prevention. Indeed, bats harboring B. nosferati in their salivary glands may transmit this pathogenic bacterium to other hosts. This potential is not trivial since, besides the demonstrated pathogenicity, this bacterium possesses all the required virulent arsenal of dangerous Brucella organisms, including those that are zoonotic for humans. Our work has settled the basis for future surveillance actions in brucellosis control programs where these infected bats thrive. Moreover, our strategy to identify the foraging range of bats may be adapted for exploring the feeding habits of diverse animals, including arthropod vectors of infectious diseases, and therefore of interest to a broader audience besides experts on Brucella and bats
Global phylogenomic diversity of Brucella abortus: spread of a dominant lineage
Brucella abortus is a globally important zoonotic pathogen largely found in cattle hosts and is typically transmitted to humans through contaminated dairy products or contact with diseased animals. Despite the long, shared history of cattle and humans, little is known about how trade in cattle has spread this pathogen throughout the world. Whole genome sequencing provides unparalleled resolution to investigate the global evolutionary history of a bacterium such as B. abortus by providing phylogenetic resolution that has been unobtainable using other methods. We report on large-scale genome sequencing and analysis of B. abortus collected globally from cattle and 16 other hosts from 52 countries. We used single nucleotide polymorphisms (SNPs) to identify genetic variation in 1,074 B. abortus genomes and using maximum parsimony generated a phylogeny that identified four major clades. Two of these clades, clade A (median date 972 CE; 95% HPD, 781–1142 CE) and clade B (median date 150 BCE; 95% HPD, 515 BCE–164 CE), were exceptionally diverse for this species and are exclusively of African origin where provenance is known. The third clade, clade C (median date 949 CE; 95% HPD, 766–1102 CE), had most isolates coming from a broad swath of the Middle East, Europe, and Asia, also had relatively high diversity. Finally, the fourth major clade, clade D (median date 1467 CE; 95% HPD, 1367–1553 CE) comprises the large majority of genomes in a dominant but relatively monomorphic group that predominantly infects cattle in Europe and the Americas. These data are consistent with an African origin for B. abortus and a subsequent spread to the Middle East, Europe, and Asia, probably through the movement of infected cattle. We hypothesize that European arrival to the Americas starting in the 15th century introduced B. abortus from Western Europe through the introduction of a few common cattle breeds infected with strains from clade D. These data provide the foundation of a comprehensive global phylogeny of this important zoonotic pathogen that should be an important resource in human and veterinary epidemiology
Brucella Genetic Variability in Wildlife Marine Mammals Populations Relates to Host Preference and Ocean Distribution
Intracellular bacterial pathogens probably arose when their ancestor adapted from a free-living environment to an intracellular one, leading to clonal bacteria with smaller genomes and less sources of genetic plasticity. Still, this plasticity is needed to respond to the challenges posed by the host. Members of the Brucella genus are facultative-extracellular intracellular bacteria responsible for causing brucellosis in a variety of mammals. The various species keep different host preferences, virulence, and zoonotic potential despite having 97–99% similarity at genome level. Here, we describe elements of genetic variation in Brucella ceti isolated from wildlife dolphins inhabiting the Pacific Ocean and the Mediterranean Sea. Comparison with isolates obtained from marine mammals from the Atlantic Ocean and the broader Brucella genus showed distinctive traits according to oceanic distribution and preferred host. Marine mammal isolates display genetic variability, represented by an important number of IS711 elements as well as specific IS711 and SNPs genomic distribution clustering patterns. Extensive pseudogenization was found among isolates from marine mammals as compared with terrestrial ones, causing degradation in pathways related to energy, transport of metabolites, and regulation/ transcription. Brucella ceti isolates infecting particularly dolphin hosts, showed further degradation of metabolite transport pathways as well as pathways related to cell wall/membrane/envelope biogenesis and motility. Thus, gene loss through pseudogenization is a source of genetic variation in Brucella, whichinturn, relates to adaptation to different hosts.This is relevant to understand the natural history of bacterial diseases, their zoonotic potential, and the impact of human interventions such as domestication.Comisión Nacional para la Gestión de la Biodiversidad/[R-028-203-OT]/CONAGEBIO/Costa RicaMinisterio de Ciencia, Tecnología y Telecomunicaciones/[FV-004-13]/MICITT/Costa RicaWellcome Trust/[098051]/WT/LondresWellcome Trust/[106690/Z/14/Z]/WT/LondresUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Centro de Investigación en Enfermedades Tropicales (CIET
Perspectivas de innovación en gestión, educación ambiental para la adaptación y la mitigación
Esta publicación del libro-foro sobre ciudad y cambio climático responde al
aporte de los diferentes profesionales de las entidades públicas y privadas que
participaron en calidad de conferencistas, ponentes, panelistas y expositores y
compartieron sus experiencias en la ciudad como una contribución al conocimiento
de las comunidades acerca de la creciente importancia y consideración de la adaptación
y mitigación. Se consideraron acciones de políticas públicas por parte de las
administraciones públicas, los sectores económicos y la sociedad, grupos ecológicos
y fundaciones ecológicas y de igual forma las acciones y grandes esfuerzos realizados
por el Ministerio del Ambiente, el IDEAM, la CAR, la Secretaría de Ambiente, el Jardín
Botánico, la Red RAUS y de los grupos de investigación de las universidades
Brucella Genomics: Macro and Micro Evolution
Brucella organisms are responsible for one of the most widespread bacterial zoonoses, named brucellosis. The disease affects several species of animals, including humans. One of the most intriguing aspects of the brucellae is that the various species show a ~97% similarity at the genome level. Still, the distinct Brucella species display different host preferences, zoonotic risk, and virulence. After 133 years of research, there are many aspects of the Brucella biology that remain poorly understood, such as host adaptation and virulence mechanisms. A strategy to understand these characteristics focuses on the relationship between the genomic diversity and host preference of the various Brucella species. Pseudogenization, genome reduction, single nucleotide polymorphism variation, number of tandem repeats, and mobile genetic elements are unveiled markers for host adaptation and virulence. Understanding the mechanisms of genome variability in the Brucella genus is relevant to comprehend the emergence of pathogens
Animal welfare in biomedical research
El bienestar animal es un tema controversial que ha tomado especial interés en los
últimos años, a la vez, lo coloca en la mira de la investigación biomédica. El uso de animales es de
gran provecho para el avance científico en el campo de la salud; sin embargo, es muy cuestionado
por sus implicaciones éticas. En este trabajo, se mencionan medidas útiles para disminuir el
dolor y el estrés, procurar bienestar en los animales de investigación, y dar el mejor manejo a
los individuos. Se mencionan algunas definiciones y cuestionamientos, desde el punto de vista
ético, para el bienestar animal. Además, se cita y comenta la legislación nacional existente al
respecto. A lo largo del trabajo, se enfatiza la importancia de conocer la especie con la cual se
trabaja, la monitorización rutinaria, la educación y el respeto hacia los animales por parte de
quienes los manipulan.Animal welfare represents a controversial topic that has attracted special interest in
recent years, and, consequently, has been brought to the attention of biomedical research. The
use of animals has greatly benefited scientific progress in the field of medical research. However,
it has been widely questioned because of its ethical implications. Useful techniques are included
in this article to decrease pain and stress in research animals, pursue their welfare, and improve
their handling. The paper also includes some definitions and ethical issues to insure animal
welfare. In addition, the national legislation is quoted and discussed. Emphasis is placed on the
importance of knowing the species with which the researcher is working, routinely monitoring,
and educating those who handle the animals and promoting respect for them.Universidad Nacional, Costa Rica.Escuela de Medicina Veterinari
Letter to the editor: It is erroneous to directly associate the detection of <i>Helicobacter</i> spp. with gastritis in canines
It has been proposed that Helicobacter may play a significant role in the generation of gastritis and cancer in dogs. However, despite several independent efforts, there is still controversy regarding the true ability of Helicobacter to cause gastric lesions in these animals. The foregoing is due in part to the fact that gastritis is a multifactorial disease. Studies focused on naturally acquired infections have been unable to establish a positive correlation between Helicobacter colonization and gastritis. Establishing a clear association between the presence of Helicobacter and gastritis may be difficult due to the following reasons: (i) taxonomy of the genus Helicobacter remains unclear, (ii) virulence factors of Helicobacter species that colonize dogs are not well known, and (iii) simultaneous infections have been reported with several species of Helicobacter. Current knowledge in taxonomy and pathogenesis of Helicobacter species is insufficient to differentiate between pathogenic and non-pathogenic strains. Therefore, no direct association should be made between the detection of Helicobacter and gastritis
Animal welfare in biomedical research
El bienestar animal es un tema controversial que ha tomado especial interés en los últimos años, a la vez, lo coloca en la mira de la investigación biomédica. El uso de animales es de gran provecho para el avance científico en el campo de la salud; sin embargo, es muy cuestionado por sus implicaciones éticas. En este trabajo, se mencionan medidas útiles para disminuir el dolor y el estrés, procurar bienestar en los animales de investigación, y dar el mejor manejo a los individuos. Se mencionan algunas definiciones y cuestionamientos, desde el punto de vista ético, para el bienestar animal. Además, se cita y comenta la legislación nacional existente al respecto. A lo largo del trabajo, se enfatiza la importancia de conocer la especie con la cual se trabaja, la monitorización rutinaria, la educación y el respeto hacia los animales por parte de quienes los manipulan.Animal welfare represents a controversial topic that has attracted special interest in recent years, and, consequently, has been brought to the attention of biomedical research. The use of animals has greatly benefited scientific progress in the field of medical research. However, it has been widely questioned because of its ethical implications. Useful techniques are included in this article to decrease pain and stress in research animals, pursue their welfare, and improve their handling. The paper also includes some definitions and ethical issues to insure animal welfare. In addition, the national legislation is quoted and discussed. Emphasis is placed on the importance of knowing the species with which the researcher is working, routinely monitoring, and educating those who handle the animals and promoting respect for them
Tetraiodothyronine, triiodothyronine and cortisol serum levels in Costa Rican dogs using an immunoassay analyzer
Los intervalos de referencia hormonales varían según el método de medición empleado
y el ambiente geoquímico donde las poblaciones se desarrollan. Por ende, cada laboratorio debe
contar con intervalos de referencia propios para interpretar adecuadamente sus resultados. El
objetivo de este trabajo fue establecer un intervalo de referencia para T4 total (TT4), T4 libre
(T4L), T3 total (TT3) y cortisol en caninos de Costa Rica mediante el analizador automatizado AIA-
360® de Tosoh Bioscience. Se utilizó suero de 122 caninos clínicamente sanos, seleccionados al
azar, para establecer los intervalos de referencia. Adicionalmente, se midió TT4, T4L y TT3 en 123
caninos con sintomatología sospechosa de hipotiroidismo, y se realizó la prueba de supresión con
dexametasona a dosis baja en 12 caninos sospechosos de hiperadrenocorticismo. Las muestras
se procesaron en el equipo AIA-360® luego de realizar las curvas de calibración respectivas
según las indicaciones del fabricante. El intervalo de referencia se estableció con base en los
percentiles 3 y 97 de los valores de caninos sanos: TT4 11,58 nmol/L - 50,19 nmol/L; T4L 6,18
pmol/L - 41,18 pmol/L; TT3 0,69 nmol/L - 1,64 nmol/L; cortisol 17,38 nmol/L - 174,64 nmol/L.
La concentración de T4L fue estadísticamente menor (p<0,05) en los caninos sospechosos de
hipotiroidismo. De los caninos sospechosos de hiperadrenocorticismo, 4 escaparon a la supresión
y 7 suprimieron a las 4 horas post dexametasona, pero mostraron efecto “rebote” a las 8 horas
posteriores. Actualmente se cuenta con un intervalo de referencia para TT4, TT3, T4L y cortisol
en caninos mediante el uso del equipo AIA-360®.Hormonal reference intervals vary according the measurement method used and the
geochemical environment where populations develop. Consequently, each lab must have its own
reference intervals in order to interpret results properly. This paper was aimed at establishing a reference interval for total T4 (TT4), free T4 (FT4), total T3 (TT3) and cortisol in Costa Rican dogs,
using the Tosoh Bioscience’s AIA-360® automatic analyzer. Blood serum from 122 randomly
selected clinically healthy canines was used to determine reference intervals. Additionally, TT4,
FT4 and TT3 were measured in 123 canines with suspected symptoms of hypothyroidism, and a
low dose dexamethasone suppression test was performed in 12 canines with suspicious signs of
hyperadrenocorticism. Samples were processed in the AIA-360® equipment after calibration
curves were performed following manufacturer’s instructions. The reference interval was estimated
based on the 3rd. and 97th. percentiles of healthy canines values: TT4 11.58 nmol/L – 50.19 nmol/L;
FT4 6.18 pmol/L – 41.18 pmol/L; TT3 0.69 nmol/L – 1.64 nmol/L; cortisol 17.38 nmol/L – 174.64
nmol/L. FT4 concentration was statistically lower (p<0.05) in canines with suspected symptoms of
hypothyroidism. Four of the canines with suspicious signs of hyperadrenocorticism did not suppress,
while 7 suppressed at 4 hours after dexamethasone, but rebounded at 8 hours. Currently, a reference
interval for TT4, FT4, TT3, and cortisol is available for Costa Rican canines using the AIA-360® analyzer.Universidad Nacional, Costa Rica.Escuela de Medicina Veterinari
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