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2.
Mol Ecol ; 30(24): 6611-6626, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34564919

RESUMEN

Neutral theory proposes that dispersal stochasticity is one of the main drivers of local diversity. Haplotypes-level genetic variation can now be efficiently sampled from across whole communities, thus making it possible to test neutral predictions from the genetic to species-level diversity, and higher. However, empirical data is still limited, with the few studies to date coming from temperate latitudes. Here, we focus on a tropical mountain within the Transmexican Volcanic Belt to evaluate spatially fine-scale patterns of arthropod community assembly to understand the role of dispersal limitation and landscape features as drivers of diversity. We sampled whole-communities of arthropods for eight orders at a spatial scale ranging from 50 m to 19 km, using whole community metabarcoding. We explored multiple hierarchical levels, from individual haplotypes to lineages at 0.5, 1.5, 3, 5, and 7.5% similarity thresholds, to evaluate patterns of richness, turnover, and distance decay of similarity with isolation-by-distance and isolation-by-resistance (costs to dispersal given by landscape features) approaches. Our results showed that distance and altitude influence distance decay of similarity at all hierarchical levels. This holds for arthropod groups of contrasting dispersal abilities, but with different strength depending on the spatial scale. Our results support a model where local-scale differentiation mediated by dispersal constraints, combined with long-term persistence of lineages, is an important driver of diversity within tropical sky islands.


Asunto(s)
Artrópodos , Biodiversidad , Altitud , Animales , Ecosistema , Haplotipos
3.
Access Microbiol ; 3(3): 000214, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34151166

RESUMEN

Enterococcus faecalis and E. faecium are Gram-positive bacteria that normally inhabit the human gastrointestinal tract. They are also opportunistic pathogens and can cause nosocomial infection outbreaks. To prevent the spread of nosocomial infections, hospitals may rely on screening methods to identify patients colonized with multidrug-resistant organisms including vancomycin-resistant enterococci (VRE). Spectra VRE agar (Remel) contains vancomycin and other medium components that select for VRE and phenotypically differentiate between E. faecalis and E. faecium by colony colour. We obtained 66 de-identified rectal swab cultures on Spectra VRE agar that were obtained during routine patient admission surveillance at a hospital system in Dallas, Texas, USA. We analysed 90 presumptive VRE from 61 of the Spectra VRE agar cultures using molecular and culture methods. Using ddl typing, 55 were found to be E. faecium and 32 were found to be E. faecalis . While most of the E. faecium were positive for the vanA gene by PCR (52 of 55 strains), few of the E. faecalis were positive for either vanA or vanB (five of 32 strains). The 27 E. faecalis vanA- and vanB-negative strains could not be recultured on Spectra VRE agar. Overall, we found that Spectra VRE agar performed robustly for the identification of vancomycin-resistant E. faecium , but presumptive false positives were obtained for vancomycin-resistant E. faecalis .

4.
Blood ; 137(18): 2544-2557, 2021 05 06.
Artículo en Inglés | MEDLINE | ID: mdl-33534893

RESUMEN

Patients with chronic graft-versus-host disease (cGVHD) have increased B cell-activating factor (BAFF) levels, but whether BAFF promotes disease after allogeneic bone marrow transplantation (allo-BMT) remains unknown. In a major histocompatibility complex-mismatched model with cGVHD-like manifestations, we first examined B-lymphopenic µMT allo-BMT recipients and found that increased BAFF levels in cGVHD mice were not merely a reflection of B-cell number. Mice that later developed cGVHD had significantly increased numbers of recipient fibroblastic reticular cells with higher BAFF transcript levels. Increased BAFF production by donor cells also likely contributed to cGVHD, because BAFF transcript in CD4+ T cells from diseased mice and patients was increased. cGVHD manifestations in mice were associated with high BAFF/B-cell ratios and persistence of B-cell receptor (BCR)-activated B cells in peripheral blood and lesional tissue. By employing BAFF transgenic (Tg) mice donor cells, we addressed whether high BAFF contributed to BCR activation in cGVHD. BAFF increased NOTCH2 expression on B cells, augmenting BCR responsiveness to surrogate antigen and NOTCH ligand. BAFF Tg B cells had significantly increased protein levels of the proximal BCR signaling molecule SYK, and high SYK protein was maintained by BAFF after in vitro BCR activation or when alloantigen was present in vivo. Using T cell-depleted (BM only) BAFF Tg donors, we found that BAFF promoted cGVHD manifestations, circulating GL7+ B cells, and alloantibody production. We demonstrate that pathologic production of BAFF promotes an altered B-cell compartment and augments BCR responsiveness. Our findings compel studies of therapeutic targeting of BAFF and BCR pathways in patients with cGVHD.


Asunto(s)
Factor Activador de Células B/metabolismo , Trasplante de Médula Ósea/efectos adversos , Enfermedad Injerto contra Huésped/patología , Proteínas Proto-Oncogénicas c-bcr/metabolismo , Receptor Notch2/metabolismo , Quinasa Syk/metabolismo , Linfocitos T/inmunología , Animales , Factor Activador de Células B/genética , Femenino , Enfermedad Injerto contra Huésped/etiología , Enfermedad Injerto contra Huésped/metabolismo , Isoanticuerpos/inmunología , Isoantígenos/inmunología , Activación de Linfocitos/inmunología , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Proteínas Proto-Oncogénicas c-bcr/genética , Receptor Notch2/genética , Quinasa Syk/genética , Trasplante Homólogo
5.
J Parasitol ; 107(1): 115-124, 2021 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-33592628

RESUMEN

The immune response of animals, including insects, is overcome by some parasites. For example, dauer larvae (DL) of the obligate entomopathogenic nematodes (EPNs) Heterorhabditis and Steinernema can invade insects, evade their defenses, and cause death. Although DL were long assumed to be the only infective stage of nematodes, recent reports suggest that L2-L3 larvae of facultative EPNs are also capable of killing insects. There are no studies, to our knowledge, about the role of nonimmunological barriers (the exoskeleton and its openings) in avoiding infection by DL and L2-L3 larvae, or whether these larval stages evade the host immune system in the same way. The objective of this study was to examine these questions by infecting Galleria mellonella with the facultative parasitic nematode Rhabditis regina. DL or L2-L3 larvae were either deposited on or near the moths or injected into their hemocoel. Once nematodes reached the hemocoel, the following host immune response parameters were quantified: prophenoloxidase, phenoloxidase, lytic activity, and the number of granular hemocytes. DL showed a greater ability to penetrate the exoskeleton than L2-L3 larvae. Once inside, however, both went unnoticed by the immune system and killed the insect. A higher number of granular hemocytes was activated by L2-L3 larvae than DL. We show for the first time that L2-L3 larvae can penetrate and evade the insect immune system. Further research is needed to compare facultative and specialized EPNs to determine which is more likely, with both DL and L2-L3 larvae, to evade insect defense barriers and produce death. The results will contribute to understanding the evolution of virulence in entomopathogenic nematodes.


Asunto(s)
Evasión Inmune/fisiología , Lepidópteros/parasitología , Strongyloidea/inmunología , Análisis de Varianza , Animales , Catecol Oxidasa/metabolismo , Proteínas Cardiotóxicas de Elápidos/metabolismo , Precursores Enzimáticos/metabolismo , Larva/inmunología , Lepidópteros/enzimología , Lepidópteros/inmunología , Monofenol Monooxigenasa/metabolismo , Strongyloidea/patogenicidad , Strongyloidea/ultraestructura , Factores de Tiempo , Virulencia
7.
Rev. argent. microbiol ; 52(4): 41-50, dic. 2020. graf
Artículo en Inglés | LILACS | ID: biblio-1340919

RESUMEN

Abstract The health benefits attributed to probiotics generate interest in the search of competent strains adapted to several ecological niches, especially those related to traditional beverages and foods of each country. Pineapple tepache, a traditional Mexican fermented beverage, was used for the isolation of lactic acid bacteria with probiotic potential, one of which withstood the in vitro tests. The isolated strain AB-05, which exhibited the tested probiotic functional properties, was designated as Lactobacillus pentosus ABHEAU-05. The sequence was registered in GenBank under access code MK587617. This study is the first report of a lactic acid bacterium with in vitro digestion resistance isolated from pineapple tepache. The survival of L. pentosus ABHEAU-05 in a symbiotic medium was proven using fermented milk enriched with inulin. The in vitro digestion-resistant probiotic activity of lactobacilli was measured through analysis of pH and proteolysis. Results showed that L. pentosus grew properly in fermented milk; therefore, this microorganism could be used in the manufacture of this kind of products. The concentration of L. pentosus reached up to 8.5 logCFU/ml after 40 h of fermentation. In addition, the production of peptides and the decrease in pH indicated the vigorous and active metabolic state of the lactic acid bacterium tested. The activity and the concentration of this microorganism were maintained during refrigeration. The results of this research conclude that L. plantarum ABHEAU-05 is an in vitro digestion-resistant microorganism that can be used as a starter culture for the production of functional foods of dairy origin.


Resumen Los beneficios a la salud atribuidos a los probióticos generan interés en la búsqueda de cepas competentes adaptadas a varios nichos ecológicos, especialmente los relacionados con bebidas y alimentos tradicionales de cada país. En este estudio, se aisló del tepache de pina, una bebida fermentada tradicional mexicana, una bacteria láctica resistente a la digestión in vitro. Entre 5 bacterias aisladas, una de ellas soportó las pruebas simuladas de digestión gastrointestinal. Se analizó la resistencia a sales biliares, a condiciones ácidas y al ataque enz-imático con pepsina. La bacteria aislada, que exhibió las propiedades funcionales probióticas referidas, fue identificada como Lactobacillus pentosus y designada como L. pentosus ABHEAU-05. La secuencia fue depositada en GenBank (acceso MK587617). Se comprobó la supervivencia de L. pentosus ABHEAU-05 en una leche fermentada adicionada con inulina y su resistencia a la digestión in vitro mediante el análisis del pH y la proteólisis. Los resultados muestran que la leche fermentada es una matriz adecuada, donde L. pentosus ABHEAU-05 se desarrolla sin inconvenientes, alcanzando un título de 8,5 logufc/ml después de 40 h de fermentación. Además, la producción de péptidos y el descenso del pH indicaron el estado metabólico vigoroso y activo del microorganismo probiótico. Se concluye que L. pentosus ABHEAU-05 es un microorganismo resistente a la digestión in vitro, que puede servir como cultivo iniciador para la producción de alimentos de origen lácteo. Este es el primer informe acerca del aislamiento de una bacteria ácido láctica resistente a la digestión in vitro a partir del tepache de piña.


Asunto(s)
Probióticos , Lactobacillus pentosus , Alimentos Fermentados , Bebidas , Ácido Láctico , Digestión , Fermentación , Microbiología de Alimentos
8.
Rev Argent Microbiol ; 52(4): 305-314, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31964562

RESUMEN

The health benefits attributed to probiotics generate interest in the search of competent strains adapted to several ecological niches, especially those related to traditional beverages and foods of each country. Pineapple tepache, a traditional Mexican fermented beverage, was used for the isolation of lactic acid bacteria with probiotic potential, one of which withstood the in vitro tests. The isolated strain AB-05, which exhibited the tested probiotic functional properties, was designated as Lactobacillus pentosus ABHEAU-05. The sequence was registered in GenBank under access code MK587617. This study is the first report of a lactic acid bacterium with in vitro digestion resistance isolated from pineapple tepache. The survival of L. pentosus ABHEAU-05 in a symbiotic medium was proven using fermented milk enriched with inulin. The in vitro digestion-resistant probiotic activity of lactobacilli was measured through analysis of pH and proteolysis. Results showed that L. pentosus grew properly in fermented milk; therefore, this microorganism could be used in the manufacture of this kind of products. The concentration of L. pentosus reached up to 8.5logCFU/ml after 40h of fermentation. In addition, the production of peptides and the decrease in pH indicated the vigorous and active metabolic state of the lactic acid bacterium tested. The activity and the concentration of this microorganism were maintained during refrigeration. The results of this research conclude that L. plantarum ABHEAU-05 is an in vitro digestion-resistant microorganism that can be used as a starter culture for the production of functional foods of dairy origin.


Asunto(s)
Alimentos Fermentados , Lactobacillus pentosus , Probióticos , Bebidas , Digestión , Fermentación , Microbiología de Alimentos , Ácido Láctico
9.
Forensic Sci Int ; 304: 109969, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31593907

RESUMEN

The new psychoactive substances (NPS) in Colombia are detected by national authorities, in blotters strip, in different circumstances and places: airports, music concerts, discos and parks. Blotters are marketed as LSD and cause several cases of intoxication and death in some consumers: due to acute intoxication or when mixed with other drugs and may have different effects on the central nervous system (CNS). This study was conducted to research into and identify the chemical composition of the drugs impregnated in the blotters sold in two Colombian cities. This research provides the analysis of 70 doses coming from forensic cases of the Colombian Attorney General's Office in Bogota and from the Laboratory of Narcotics of the Colombian National Institute of Legal Medicine and Forensic Sciences (North Headquarter) in Barranquilla. Mixtures of drugs, such as DOB, 25I-NBOMe, MDMA and 25I-NBOMe imine were found within the blotters through gas chromatography coupled to mass spectrometry (CGMS); these drugs are classified by international authorities as NPS belonging to the phenylethylamines group. The results clearly warn about a growing public health problem in the country.


Asunto(s)
2,5-Dimetoxi-4-Metilanfetamina/análogos & derivados , Dimetoxifeniletilamina/análogos & derivados , Tráfico de Drogas , Drogas Ilícitas/aislamiento & purificación , N-Metil-3,4-metilenodioxianfetamina/aislamiento & purificación , 2,5-Dimetoxi-4-Metilanfetamina/aislamiento & purificación , Administración Sublingual , Colombia , Drogas de Diseño/aislamiento & purificación , Dimetoxifeniletilamina/aislamiento & purificación , Contaminación de Medicamentos , Humanos , Papel , Trastornos Relacionados con Sustancias
10.
Mucosal Immunol ; 12(1): 145-153, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30279513

RESUMEN

Severe, chronic eye allergy is an understudied, vision-threatening condition. Treatments remain limited. We used a mouse model of severe allergic eye disease (AED) to determine whether topical application of the pro-resolution mediator Resolvin D1 (RvD1) terminates the response. AED was induced by injection of ovalbumin (OVA) followed by topical challenge of OVA daily. RvD1 was applied topically prior to OVA. Clinical symptoms were scored. Eye washes were assayed for MUC5AC. After 7 days, eyes were removed and the number of goblet cells, T helper cell responses and presence of immune cells in draining lymph nodes and conjunctiva determined. Topical RvD1 treatment significantly reduced symptoms of AED. RvD1 did not alter the systemic type 2 immune response in the lymph nodes. AED increased the total amount of goblet cell mucin secretion, but not the number of goblet cells. RvD1 prevented this increase, but did not alter goblet cell number. Absolute numbers of CD4 + T cells, total CD11b + myeloid cells, eosinophils, neutrophils, and monocytes, but not macrophages increased in AED versus RvD1-treated mice. We conclude that topical application of RvD1 reduced the ocular allergic response by local actions in conjunctival immune response and a decrease in goblet cell mucin secretion.


Asunto(s)
Ácidos Docosahexaenoicos/metabolismo , Oftalmopatías/inmunología , Células Caliciformes/fisiología , Hipersensibilidad/inmunología , Mucina 5AC/metabolismo , Alérgenos/inmunología , Animales , Células Cultivadas , Enfermedad Crónica , Modelos Animales de Enfermedad , Humanos , Inmunidad Celular , Ratones , Ratones Endogámicos C57BL , Ovalbúmina/inmunología
11.
Methods Mol Biol ; 1834: 153-164, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30324443

RESUMEN

With the new understanding that adult microglia in mice have embryonic origins and are maintained in situ throughout life, it has become pertinent to now understand how these unique cells differ from monocyte-derived macrophages. The latter are recruited into the neural retina (and elsewhere in CNS) in certain diseased states, such as in various forms of retinal degeneration. However, phenotypic markers expressed by microglia and monocyte-derived macrophages largely overlap, thereby making it technically challenging to distinguish the two cell types in disease. To address this problem in mice, we have established an in vivo fate mapping system that enables distinguishing these two cell types in retinal disease models. Our approach leverages the seminal work that originally developed Cx3cr1-CreER mice and is based on commercially available mouse strains. Here, we detail our protocol and how to apply this fate mapping method paired with flow cytometry (or immunohistochemistry) to faithfully distinguish and examine microglia vs. monocyte-derived macrophages in a mutually exclusive manner. This approach will henceforth empower new efforts to identify functional specializations of these two populations in the pathobiology of retinal degenerative diseases and possibly other conditions of the retina where monocyte recruitment is observed, such as in glaucoma, diabetic retinopathy, ischemia reperfusion, retinal detachment, and so on.


Asunto(s)
Macrófagos/metabolismo , Microglía/metabolismo , Enfermedades de la Retina/etiología , Enfermedades de la Retina/metabolismo , Animales , Biomarcadores , Supervivencia Celular , Modelos Animales de Enfermedad , Citometría de Flujo , Expresión Génica , Genes Reporteros , Leucocitos/inmunología , Leucocitos/metabolismo , Macrófagos/inmunología , Ratones , Ratones Transgénicos , Microglía/inmunología , Microscopía Confocal , Enfermedades de la Retina/patología
12.
JCI Insight ; 3(19)2018 10 04.
Artículo en Inglés | MEDLINE | ID: mdl-30282825

RESUMEN

Graft-versus-host disease (GVHD) is a major complication of hematopoietic stem cell transplantation (HCT). The tyrosine kinase SYK contributes to both acute and chronic GVHD development, making it an attractive target for GVHD prevention. Entospletinib (ENTO) is a second-generation highly selective SYK inhibitor with a high safety profile. Potential utility of ENTO as GVHD prophylaxis in patients was examined using a preclinical mouse model of eye and skin GVHD and ENTO-compounded chow. We found that early SYK inhibition improved blood immune cell reconstitution in GVHD mice and prolonged survival, with 60% of mice surviving to day +120 compared with 10% of mice treated with placebo. Compared with mice receiving placebo, mice receiving ENTO had dramatic improvements in clinical eye scores, alopecia scores, and skin scores. Infiltrating SYK+ cells expressing B220 or F4/80, resembling SYK+ cells found in lichenoid skin lesions of chronic GVHD patients, were abundant in the skin of placebo mice but were rare in ENTO-treated mice. Thus, ENTO given early after HCT safely prevented GVHD.


Asunto(s)
Enfermedad Injerto contra Huésped/prevención & control , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Indazoles/administración & dosificación , Inhibidores de Proteínas Quinasas/administración & dosificación , Pirazinas/administración & dosificación , Quinasa Syk/antagonistas & inhibidores , Administración Oral , Animales , Linfocitos B/efectos de los fármacos , Linfocitos B/inmunología , Linfocitos B/metabolismo , Modelos Animales de Enfermedad , Evaluación Preclínica de Medicamentos , Ojo/efectos de los fármacos , Ojo/inmunología , Ojo/patología , Femenino , Enfermedad Injerto contra Huésped/inmunología , Enfermedad Injerto contra Huésped/mortalidad , Humanos , Ratones , Piel/efectos de los fármacos , Piel/inmunología , Piel/patología , Análisis de Supervivencia , Quinasa Syk/inmunología , Quinasa Syk/metabolismo , Linfocitos T/efectos de los fármacos , Linfocitos T/inmunología , Linfocitos T/metabolismo , Resultado del Tratamiento
13.
Sci Transl Med ; 10(451)2018 07 25.
Artículo en Inglés | MEDLINE | ID: mdl-30045980

RESUMEN

Meibomian glands (MGs) are sebaceous glands of the eyelid margin that secrete lipids needed to avert tear evaporation and to help maintain ocular surface homeostasis. Obstruction of MGs or other forms of MG dysfunction can promote chronic diseases of the ocular surface. Although chronic eyelid inflammation, such as allergic eye disease, is an associated risk factor for obstructive MG dysfunction, it is not clear whether inflammatory processes contribute to the pathophysiology of MG obstruction. We show that polymorphonuclear neutrophils (PMNs) promoted MG obstruction in a chronic inflammatory model of allergic eye disease in mice. Analysis of leukocytes in tears of patients with MG dysfunction showed an increase in PMN numbers compared to healthy subjects. Moreover, PMN numbers in tears positively correlated with clinical severity of MG dysfunction. Our findings point to a role for PMNs in the pathogenesis and progression of MG dysfunction.


Asunto(s)
Enfermedades de los Párpados/inmunología , Enfermedades de los Párpados/patología , Glándulas Tarsales/inmunología , Glándulas Tarsales/patología , Glándulas Sebáceas/inmunología , Glándulas Sebáceas/patología , Animales , Ratones , Ratones Endogámicos C57BL , Neutrófilos/metabolismo
14.
Methods Mol Biol ; 1799: 49-57, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29956143

RESUMEN

Ocular IgE-associated allergy ranges from mild disease (seasonal and perennial allergic conjunctivitis) to more chronic/severe and vision-threatening forms (atopic and vernal keratoconjunctivitis). Whereas mild forms of disease have been studied extensively, less is known about the more chronic forms. Our lab has helped to address this knowledge gap by developing and characterizing an allergen-induced, chronic/severe, IgE-associated model of ocular allergy referred to as the severe allergic eye disease (AED) model. It is distinct from previously described models that mimic the more mild forms, referred to in the literature as the allergic conjunctivitis (AC) model. The purpose of this method article is to detail the protocol to induce and characterize the AED model and directly compare these mice to the mild AC model. Troubleshooting and implications are also discussed.


Asunto(s)
Oftalmopatías/diagnóstico , Oftalmopatías/etiología , Hipersensibilidad/diagnóstico , Hipersensibilidad/etiología , Alérgenos/inmunología , Animales , Conjuntivitis Alérgica/diagnóstico , Conjuntivitis Alérgica/etiología , Citocinas/metabolismo , Células Dendríticas/inmunología , Células Dendríticas/metabolismo , Modelos Animales de Enfermedad , Ojo/inmunología , Ojo/patología , Femenino , Mediadores de Inflamación/metabolismo , Ratones , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/metabolismo
15.
Immunity ; 47(1): 6-8, 2017 07 18.
Artículo en Inglés | MEDLINE | ID: mdl-28723553

RESUMEN

"Paucibacterial" levels of the normal eye surface have left immunologists wondering whether a true microbiome exists there. In this issue of Immunity, St. Leger et al. (2017) address this head-on, discovering a naturally existing commensal in mice that induces γδT cell-mediated protection from opportunistic infection.


Asunto(s)
Inmunidad , Microbiota , Animales , Ratones
16.
Nat Rev Immunol ; 17(5): 322-332, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28345586

RESUMEN

Major advances in mononuclear phagocyte biology have been made but key questions pertinent to their roles in health and disease remain, including in the visual system. One problem concerns how dendritic cells can trigger immune responses from certain tightly regulated immune- privileged sites of the eye. Another, albeit separate, problem involves whether there are functional specializations for microglia versus monocytes in retinal neurodegeneration. In this Review, we examine novel insights in eye immune privilege and, separately, we discuss recent inroads concerning retinal degeneration. Both themes have been extensively studied in the visual system and show parallels with recent findings concerning mononuclear phagocytes in the central nervous system and in the periphery.


Asunto(s)
Ojo/inmunología , Sistema Mononuclear Fagocítico/inmunología , Animales , Ojo/citología , Humanos , Retina/citología , Retina/inmunología , Percepción Visual
17.
JCI Insight ; 1(12)2016 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-27595139

RESUMEN

Fibrosis is a shared end-stage pathway to lung, liver, and heart failure. In the ocular mucosa (conjunctiva), fibrosis leads to blindness in trachoma, pemphigoid, and allergy. The indirect fibrogenic role of DCs via T cell activation and inflammatory cell recruitment is well documented. However, here we demonstrate that DCs can directly induce fibrosis. In the mouse model of allergic eye disease (AED), classical CD11b+ DCs in the ocular mucosa showed increased activity of aldehyde dehydrogenase (ALDH), the enzyme required for retinoic acid synthesis. In vitro, CD11b+ DC-derived ALDH was associated with 9-cis-retinoic acid ligation to retinoid x receptor (RXR), which induced conjunctival fibroblast activation. In vivo, stimulating RXR led to rapid onset of ocular mucosal fibrosis, whereas inhibiting ALDH activity in DCs or selectively depleting DCs markedly reduced fibrosis. Collectively, these data reveal a profibrotic ALDH-dependent pathway by DCs and uncover a role for DC retinoid metabolism.

18.
Parasitol Res ; 115(11): 4153-4165, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27492201

RESUMEN

Here we report the presence of the entomopathogenic nematode Rhabditis (Rhabditoides) regina affecting white grubs (Phyllophaga sp. and Anomala sp.) in Mexico and R. regina-associated bacteria. Bioassays were performed to test the entomopathogenic capacity of dauer and L2 and L3 (combined) larval stages. Furthermore, we determined the diversity of bacteria from laboratory nematodes cultivated for 2 years (dauer and L2-L3 larvae) and from field nematodes (dauer and L2-L3 larvae) in addition to the virulence in Galleria mellonella larvae of some bacterial species from both laboratory and field nematodes. Dauer and non-dauer larvae of R. regina killed G. mellonella. Bacteria such as Serratia sp. (isolated from field nematodes) and Klebsiella sp. (isolated from larvae of laboratory and field nematodes) may explain R. regina entomopathogenic capabilities. Different bacteria were found in nematodes after subculturing in the laboratory suggesting that R. regina may acquire bacteria in different environments. However, there were some consistently found bacteria from laboratory and field nematodes such as Pseudochrobactrum sp., Comamonas sp., Alcaligenes sp., Klebsiella sp., Acinetobacter sp., and Leucobacter sp. that may constitute the nematode microbiome. Results showed that some bacteria contributing to entomopathogenicity may be lost in the laboratory representing a disadvantage when nematodes are cultivated to be used for biological control.


Asunto(s)
Bacterias/aislamiento & purificación , Escarabajos/parasitología , Microbiota , Mariposas Nocturnas/parasitología , Rhabditoidea/microbiología , Animales , Bacterias/genética , Bacterias/patogenicidad , Klebsiella/genética , Klebsiella/aislamiento & purificación , Klebsiella/patogenicidad , Larva , México , Filogenia , Análisis de Secuencia de ADN , Serratia/genética , Serratia/aislamiento & purificación , Serratia/patogenicidad , Virulencia
19.
Rev. Fac. Med. (Bogotá) ; 63(3): 465-469, jul.-sep. 2015. ilus
Artículo en Español | LILACS | ID: lil-757303

RESUMEN

Antecedentes. El aldicarb es un plaguicida carbamato de alta toxicidad asociado a intoxicaciones agudas fatales en el ser humano. Su mecanismo de acción consiste en la inhibición de la enzima acetilcolinesterasa (AChE) que ocasiona la acumulación del neurotransmisor acetilcolina en la hendidura sináptica. Esta acumulación provoca síntomas colinérgicos y, dependiendo de la dosis de exposición, puede paralizar los sistemas respiratorio y nervioso hasta llegar a la muerte. Objetivo. Determinar el nivel de aldicarb en sangre post mortem en casos de intoxicación aguda. Materiales y métodos. Investigación de tipo experimental empleando un cromatógrafo líquido con espectrometría de masas, con ionización electrospray y análisis en modo tándem (LC-ESI-MS/MS). Los estándares de aldicarb y el aldicarb-d3 fueron comprados de Dr. Ehrenstorfer GmbH. El método consiste en una precipitación de proteínas de la sangre y su posterior análisis por LC-ESI-MS/MS, utilizando el aldicarb-d3 como estándar interno. El método fue aplicado a siete casos de intoxicación letal por presunta acción del aldicarb. Resultados. El aldicarb se encontró en la sangre de seis de los casos estudiados, en niveles desde 0.12 a 1.90 µg/mL. Solo en uno de los casos no se detectó aldicarb. En cuanto la presunta manera de muerte, en seis de los casos analizados fue el suicidio y en un caso se clasificó como muerte en estudio. Conclusiones. Los resultados obtenidos con la metodología analítica y la técnica LC-ESI-MS/MS son satisfactorios en términos de la determinación cuantitativa de aldicarb en sangre total post mortem. La aplicación de la metodología descrita en toxicología forense evidencia el empleo de este plaguicida en actos suicidas.


Background. Aldicarb is a high toxicity carbamate pesticide associated to human fatal acute intoxications. Its mechanism of action consists of the inhibition of the acetylcholinesterase enzyme (AChE), which induces the accumulation of the neurotransmitter acetylcholine in the synaptic cleft. This accumulation induces cholinergic symptoms and, depending on the exposition dose, it can paralyze the respiratory and nervous systems, leading to death. Objective. To determine aldicarb levels in post mortem blood in cases of acute intoxication. Materials and methods. An experimental research was conducted using liquid chromatography tandem-mass spectrometry (LC-ESI-MS/MS) with electrospray ionization. The aldicarb and aldicarb-d3 standards were purchased from Dr. Ehrenstorfer GmbH corporation. This method carries out a protein precipitation of blood and its analysis using LC-ESI-MS/MS, using aldicarb-d3 as internal standard. This method was applied to seven cases of fatal intoxication by presumable action of aldicarb. Results. Aldicarb was found in six of the studied cases on levels between 0.12 and 1.90 µg/mL. Aldicarb was not detected in blood only in one case. Six of the cases were associated to suicide as a manner of death and in one of them it remained under study. Conclusions. The results obtained with the analytical methodology and the use of the LC-ESI-MS/MS technique are satisfactory in terms of the quantitative determination of aldicarb in post mortem total blood. The application of the described methodology in forensic toxicology evidences the use of this pesticide in suicidal practices.

20.
Invest Ophthalmol Vis Sci ; 56(5): 3140-8, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-26024097

RESUMEN

PURPOSE: The contribution of lymphangiogenesis (LA) to allergy has received considerable attention and therapeutic inhibition of this process via targeting VEGF has been considered. Likewise, certain inflammatory settings affecting the ocular mucosa can trigger pathogenic LA in the naturally avascular cornea. Chronic inflammation in allergic eye disease (AED) impacts the conjunctiva and cornea, leading to sight threatening conditions. However, whether corneal LA is involved is completely unknown. We addressed this using a validated mouse model of AED. METHODS: Allergic eye disease was induced by ovalbumin (OVA) immunization and chronic OVA exposure. Confocal microscopy of LYVE-1-stained cornea allowed evaluation of corneal LA, and qRT-PCR was used to evaluate expression of VEGF-C, -D, and -R3 in these mice. Administration of VEGF receptor (R) inhibitor was incorporated to inhibit corneal LA in AED. Immune responses were evaluated by in vitro OVA recall responses of T cells, and IgE levels in the serum. RESULTS: Confocal microscopy of LYVE-1-stained cornea revealed the distinct presence of corneal LA in AED, and corroborated by increased corneal expression of VEGF-C, -D, and -R3. Importantly, prevention of corneal LA in AED via VEGFR inhibition was associated with decreased T helper two responses and IgE production. Furthermore, VEGFR inhibition led a significant reduction in clinical signs of AED. CONCLUSIONS: Collectively, these data reveal that there is a distinct involvement of corneal LA in AED. Furthermore, VEGFR inhibition prevents corneal LA and consequent immune responses in AED.


Asunto(s)
Córnea/fisiología , Modelos Animales de Enfermedad , Queratoconjuntivitis/fisiopatología , Linfangiogénesis/fisiología , Vasos Linfáticos/fisiopatología , Animales , Axitinib , Femenino , Glicoproteínas/metabolismo , Imidazoles/farmacología , Inmunoglobulina E/sangre , Indazoles/farmacología , Queratoconjuntivitis/metabolismo , Queratoconjuntivitis/patología , Proteínas de Transporte de Membrana , Ratones , Ratones Endogámicos C57BL , Microscopía Confocal , Ovalbúmina/farmacología , Inhibidores de Proteínas Quinasas/farmacología , Reacción en Cadena en Tiempo Real de la Polimerasa , Factor C de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Factor C de Crecimiento Endotelial Vascular/metabolismo , Factor D de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Factor D de Crecimiento Endotelial Vascular/metabolismo , Receptor 3 de Factores de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Receptor 3 de Factores de Crecimiento Endotelial Vascular/metabolismo
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