93 research outputs found
Ilícito contrabando de mercaderías en la zona oriental de El Salvador
En el desarrollo del presente trabajo se realiza un estudio del ilícito Contrabando de Mercadería, regulado en el artículo 15 de la Ley Especial Para Sancionar Infracciones Aduaneras, investigación que se ha denominado “ILÍCITO CONTRABANDO DE MERCADERÍA EN LA ZONA ORIENTAL DE EL SALVADOR” haciendo un análisis Doctrinario, Jurídico y Social. Los objetivo principal planteado en la investigación nos señala que desea; estudiar la Regulación Penal del Delito Contrabando de Mercaderías, como también analizar el Tipo Penal Contrabando de Mercadería. Para el desarrollo del tema objeto de estudio se tomara el método científico por los esfuerzos sistemáticos de comprensión, provocado por una necesidad o una dificultad de la que se ha tomado conciencia, dedicado al estudio de un fenómeno complejo; cuyo interés supera las preocupaciones personales e inmediatas, siendo planteado el problema en forma de hipótesis tendiente a una explicación general. La conclusión jurídica más acertada nos dice que; La Constitución de la República en su Titulo VII Capitulo II preceptúa lo relativo a la Hacienda Publica, Bien Jurídico genérico protegido con el tipo de Contrabando de Mercedaria; éste se encuentra regulado en la Ley Especial para Sancionar Infracciones Aduaneras, no obstante que en el Titulo IX, Capitulo V del Código Penal se tipifican los delitos relativos a la Hacienda Publica, el de contrabando lo contiene una ley penal accesoria. La Ley Especial para Sancionar Infracciones Aduaneras es creada con la finalidad de unificar en un cuerpo de leyes todas las infracciones aduaneras incluso las penales, regula entre otras la de contrabando, preceptuándolo como delito en el Art. 15 que contiene los supuestos de hecho y en el Art.16 la consecuencia jurídic
Color kinetics for roasted coffee using image analysis IMAGEJ
Se estudió el nivel de color usando la escala L*, a* y b* para grano tostado de café (Coffea
arábica), preparada para masas iniciales de 500 g con humedad inicial de 12,5 % b.h.. Se utilizó
un tostador tipo convencional, donde se mantuvo estable la temperatura inicial del tostador y se
produjeron cinco niveles de tostado. Cada muestra fue molida y las partículas fueron clasificadas
por tamaño 60 mesh, luego fueron analizadas tomando fotografías, para las cuales se utilizó análisis
de imágenes usando el software ImageJ. Se analizó el cambio de color a través de los valores de
L*, a* y b* asociados al tiempo para los distintos grados de tueste y estudiaron los valores promedio
para el total de pixeles y se encontró que la regresión de mejor ajuste corresponde a una curva
polinómica de segundo grado con valores del coeficiente de determinación mayores al 98 %.
Adicionalmente se encontró que entre mayor el grado de tostado, menor la desviación estándar de
dichas escalas, mostrando mayor uniformidad en el análisis. Esto permite correlacionar de manera
objetiva los grados de tueste de un modo que expresa la importancia de la metodología que es
versátil, rápida y económica al hacer uso de software libre.Digital Image Processing has the potential to objectively correlate the color of coffee roast
levels with a versatile, quick and economic methodology as it can use free software. Color levels
were studied using the L*, a* y b* scale for the roasted Coffea Arabica species, prepared for a mass
and initial humidity of 500 g and 12,5 % w.b., respectively. A rotary drum toaster was used, where
the initial toaster temperature was kept constant and five different roasting levels were obtained.
Each sample was milled and classified by size using a 60 mesh screen, and then analyzed capturing
images which were later processed using the software ImageJ. Color differences were studied by
the measured changes of the L*, a* y b values through time for the different roast degrees, for
which an average pixel value was determined. A second degree polynomial equation was
determined for the color kinetics, with coefficient of determination values higher than 98%. It was also discovered that the greater the roasting levels, the lower the standard deviation on pixel color
values, showing more sample uniformity.Universidad de Costa Rica/[734-B5-A86]/UCR/Costa RicaUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Agroalimentarias::Centro para Investigaciones en Granos y Semillas (CIGRAS)UCR::Vicerrectoría de Docencia::Ingeniería::Facultad de Ingeniería::Escuela de Ingeniería de Biosistema
Neutrophils as Trojan Horse Vehicles for Brucella abortus Macrophage Infection
Brucella abortus is a stealthy intracellular bacterial pathogen of animals and humans. This bacterium promotes the premature cell death of neutrophils (PMN) and resists the killing action of these leukocytes. B. abortus-infected PMNs presented phosphatidylserine (PS) as “eat me” signal on the cell surface. This signal promoted direct contacts between PMNs and macrophages (Mϕs) and favored the phagocytosis of the infected dying PMNs. Once inside Mϕs, B. abortus replicated within Mϕs at significantly higher numbers than when Mϕs were infected with bacteria alone. The high levels of the regulatory IL-10 and the lower levels of proinflammatory TNF-α released by the B. abortus-PMN infected Mϕs, at the initial stages of the infection, suggested a non-phlogistic phagocytosis mechanism. Thereafter, the levels of proinflammatory cytokines increased in the B. abortus-PMN-infected Mϕs. Still, the efficient bacterial replication proceeded, regardless of the cytokine levels and Mϕ type. Blockage of PS with Annexin V on the surface of B. abortus-infected PMNs hindered their contact with Mϕs and hampered the association, internalization, and replication of B. abortus within these cells. We propose that B. abortus infected PMNs serve as “Trojan horse” vehicles for the efficient dispersion and replication of the bacterium within the host
The Differential Interaction of Brucella and Ochrobactrum with Innate Immunity Reveals Traits Related to the Evolution of Stealthy Pathogens
International audienceBACKGROUND: During evolution, innate immunity has been tuned to recognize pathogen-associated molecular patterns. However, some alpha-Proteobacteria are stealthy intracellular pathogens not readily detected by this system. Brucella members follow this strategy and are highly virulent, but other Brucellaceae like Ochrobactrum are rhizosphere inhabitants and only opportunistic pathogens. To gain insight into the emergence of the stealthy strategy, we compared these two phylogenetically close but biologically divergent bacteria. METHODOLOGY/PRINCIPAL FINDINGS: In contrast to Brucella abortus, Ochrobactrum anthropi did not replicate within professional and non-professional phagocytes and, whereas neutrophils had a limited action on B. abortus, they were essential to control O. anthropi infections. O. anthropi triggered proinflammatory responses markedly lower than Salmonella enterica but higher than B. abortus. In macrophages and dendritic cells, the corresponding lipopolysaccharides reproduced these grades of activation, and binding of O. anthropi lipopolysaccharide to the TLR4 co-receptor MD-2 and NF-kappaB induction laid between those of B. abortus and enteric bacteria lipopolysaccharides. These differences correlate with reported variations in lipopolysaccharide core sugars, sensitivity to bactericidal peptides and outer membrane permeability. CONCLUSIONS/SIGNIFICANCE: The results suggest that Brucellaceae ancestors carried molecules not readily recognized by innate immunity, so that non-drastic variations led to the emergence of stealthy intracellular parasites. They also suggest that some critical envelope properties, like selective permeability, are profoundly altered upon modification of pathogen-associated molecular patterns, and that this represents a further adaptation to the host. It is proposed that this adaptive trend is relevant in other intracellular alpha-Proteobacteria like Bartonella, Rickettsia, Anaplasma, Ehrlichia and Wolbachia
N-Formyl-Perosamine Surface Homopolysaccharides Hinder the Recognition of Brucella abortus by Mouse Neutrophils
Brucella abortus is an intracellular pathogen of monocytes, macrophages, dendritic cells, and placental trophoblasts. This bacterium
causes a chronic disease in bovines and in humans. In these hosts, the bacterium also invades neutrophils; however, it fails
to replicate and just resists the killing action of these leukocytes without inducing significant activation or neutrophilia. Moreover,
B. abortus causes the premature cell death of human neutrophils. In the murine model, the bacterium is found within macrophages
and dendritic cells at early times of infection but seldom in neutrophils. Based on this observation, we explored the
interaction of mouse neutrophils with B. abortus. In contrast to human, dog, and bovine neutrophils, naive mouse neutrophils
fail to recognize smooth B. abortus bacteria at early stages of infection. Murine normal serum components do not opsonize
smooth Brucella strains, and neutrophil phagocytosis is achieved only after the appearance of antibodies. Alternatively, mouse
normal serum is capable of opsonizing rough Brucella mutants. Despite this, neutrophils still fail to kill Brucella, and the bacterium
induces cell death of murine leukocytes. In addition, mouse serum does not opsonize Yersinia enterocolitica O:9, a bacterium
displaying the same surface polysaccharide antigen as smooth B. abortus. Therefore, the lack of murine serum opsonization
and absence of murine neutrophil recognition are specific, and the molecules responsible for the Brucella camouflage are
N-formyl-perosamine surface homopolysaccharides. Although the mouse is a valuable model for understanding the immunobiology
of brucellosis, direct extrapolation from one animal system to another has to be undertaken with caution.Fondo Especial de la Educación Superior/[UNA-SIA-0505-13]/FEES-CONARE/Costa RicaFondo Especial de la Educación Superior/[UNA-SIA-0504-13]/FEES-CONARE/Costa RicaFondo Especial de la Educación Superior/[UNA-SIA-0248-13]/FEES-CONARE/Costa RicaFondo Especial de la Educación Superior/[UNA-SIA-0434-14]/FEES-CONARE/Costa RicaConsejo Nacional para Investigaciones Científicas y Tecnológicas/[FV-0004-13]/CONICIT-FORINVES/Costa RicaThe International Center for Genomic Engineering and Biotechnology/[CRP/12/007]/ICGEB/IndiaUniversidad de Costa Rica/[803-B3-761]/UCR/Costa RicaUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Centro de Investigación en Enfermedades Tropicales (CIET
Depletion of complement enhances the clearance of Brucella abortus in mice
Brucellosis is a bacterial disease of animals and humans. Brucella abortus
barely activates the innate immune system at the onset of infection, and this
bacterium is resistant to the microbicidal action of complement. Since complement
stands as the first line of defense during bacterial invasions, we explored the role of
complement in B. abortus infections. Brucella abortus-infected mice depleted of complement
with cobra venom factor (CVF) showed the same survival rate as mice in
the control group. The complement-depleted mice readily eliminated B. abortus
from the spleen and did so more efficiently than the infected controls after 7 days
of infection. The levels of the proinflammatory cytokines tumor necrosis factor alpha
and interleukin-6 (IL-6) remained within background levels in complement-depleted
B. abortus-infected mice. In contrast, the levels of the immune activator cytokine
gamma interferon and the regulatory cytokine IL-10 were significantly increased. No
significant histopathological changes in the liver and spleen were observed between
the complement-depleted B. abortus-infected mice and the corresponding controls.
The action exerted by Brucella on the immune system in the absence of complement
may correspond to a broader phenomenon that involves several components
of innate immunity.Universidad de Costa Rica/[803-B0-601]/UCR/Costa RicaUniversidad de Costa Rica/[803-B8-762]/UCR/Costa RicaInternational Centre for Genetic Engineering and Biotechnology/[CRP/16/005]/ICGBE/ArgentinaUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Instituto Clodomiro Picado (ICP)UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Centro de Investigación en Enfermedades Tropicales (CIET)UCR::Vicerrectoría de Docencia::Salud::Facultad de Microbiologí
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
The Lipopolysaccharide Core of Brucella abortus Acts as a Shield Against Innate Immunity Recognition
Innate immunity recognizes bacterial molecules bearing pathogen-associated molecular patterns to launch inflammatory responses leading to the activation of adaptive immunity. However, the lipopolysaccharide (LPS) of the gram-negative bacterium Brucella lacks a marked pathogen-associated molecular pattern, and it has been postulated that this delays the development of immunity, creating a gap that is critical for the bacterium to reach the intracellular replicative niche. We found that a B. abortus mutant in the wadC gene displayed a disrupted LPS core while keeping both the LPS O-polysaccharide and lipid A. In mice, the wadC mutant induced proinflammatory responses and was attenuated. In addition, it was sensitive to killing by non-immune serum and bactericidal peptides and did not multiply in dendritic cells being targeted to lysosomal compartments. In contrast to wild type B. abortus, the wadC mutant induced dendritic cell maturation and secretion of pro-inflammatory cytokines. All these properties were reproduced by the wadC mutant purified LPS in a TLR4-dependent manner. Moreover, the core-mutated LPS displayed an increased binding to MD-2, the TLR4 co-receptor leading to subsequent increase in intracellular signaling. Here we show that Brucella escapes recognition in early stages of infection by expressing a shield against recognition by innate immunity in its LPS core and identify a novel virulence mechanism in intracellular pathogenic gram-negative bacteria. These results also encourage for an improvement in the generation of novel bacterial vaccines
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
Brucella abortus Uses a Stealthy Strategy to Avoid Activation of the Innate Immune System during the Onset of Infection
To unravel the strategy by which Brucella abortus establishes chronic infections, we explored its early interaction with innate immunity.
Methodology/Principal Findings
Brucella did not induce proinflammatory responses as demonstrated by the absence of leukocyte recruitment, humoral or cellular blood changes in mice. Brucella hampered neutrophil (PMN) function and PMN depletion did not influence the course of infection. Brucella barely induced proinflammatory cytokines and consumed complement, and was strongly resistant to bactericidal peptides, PMN extracts and serum. Brucella LPS (BrLPS), NH-polysaccharides, cyclic glucans, outer membrane fragments or disrupted bacterial cells displayed low biological activity in mice and cells. The lack of proinflammatory responses was not due to conspicuous inhibitory mechanisms mediated by the invading Brucella or its products. When activated 24 h post-infection macrophages did not kill Brucella, indicating that the replication niche was not fusiogenic with lysosomes. Brucella intracellular replication did not interrupt the cell cycle or caused cytotoxicity in WT, TLR4 and TLR2 knockout cells. TNF-α-induction was TLR4- and TLR2-dependent for live but not for killed B. abortus. However, intracellular replication in TLR4, TLR2 and TLR4/2 knockout cells was not altered and the infection course and anti-Brucella immunity development upon BrLPS injection was unaffected in TLR4 mutant mice.
Conclusion/Significance
We propose that Brucella has developed a stealth strategy through PAMPs reduction, modification and hiding, ensuring by this manner low stimulatory activity and toxicity for cells. This strategy allows Brucella to reach its replication niche before activation of antimicrobial mechanisms by adaptive immunity. This model is consistent with clinical profiles observed in humans and natural hosts at the onset of infection and could be valid for those intracellular pathogens phylogenetically related to Brucella that also cause long lasting infections
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