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1.
Front Microbiol ; 13: 907631, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35770175

RESUMO

A mouse model of cutaneous leishmaniasis (CL) by Leishmania (Viannia) panamensis (L(V)p) that reproduces the characteristics of the human disease remains elusive. Here we report the development of a CL model that uses a mouse-adapted L(V)p isolate to reproducibly induce a dermal disease with a remarkable similarity to human CL. BALB/c mice infected intradermally in the ear with 105 stationary UA-946 L(V)p promastigotes develop a progressive cutaneous disease that exhibits the typical ulcerated lesions with indurated borders observed in CL patients. Although most of parasites in the inoculum die within the first week of infection, the survivors vigorously multiply at the infection site during the following weeks, paralleling disease appearance and aggravation. Regional lymphadenopathy as well as lymphatic dissemination of parasites to draining lymph nodes (dLN) was evidenced early after infection. Viable parasites were also isolated from spleen at later timepoints indicating systemic parasitic dissemination, but, strikingly, no signs of systemic disease were observed. Increasing numbers of myeloid cells and T lymphocytes producing IFNγ and IL-4 were observed in the dLN as disease progressed. A mixed adaptive L(V)p-specific T cell-mediated response was induced, since ex vivo recall experiments using dLN cells and splenocytes revealed the production of type 1 (IFNγ, IL-2), type 2 (IL-4, IL-13), regulatory (IL-10), and inflammatory (GM-CSF, IL-3) cytokines. Humoral adaptive response was characterized by early production of IgG1- followed by IgG2a-type of L(V)p-specific antibodies. IFNγ/IL-4 and IgG2a/IgG1 ratios indicated that the initial non-protective Th2 response was redirected toward a protective Th1 response. In situ studies revealed a profuse recruitment of myeloid cells and of IFNγ- and IL-4-producing T lymphocytes to the site of infection, and the typical histopathological changes induced by dermotropic Leishmania species. Evidence that this model is suitable to investigate pharmacological and immunomodulatory interventions, as well as for antigen discovery and vaccine development, is also presented. Altogether, these results support the validity and utility of this novel mouse model to study the pathogenesis, immunity, and therapeutics of L(V)p infections.

2.
J Pharmacol Exp Ther ; 343(2): 296-306, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22869926

RESUMO

Many studies have demonstrated that the flavonoid quercetin protects against cardiovascular disease (CVD) and related risk factors. Atherosclerosis, the underlying cause of CVD, is also attenuated by oral quercetin administration in animal models. Although macrophages are key players during fatty streak formation and plaque progression and aggravation, little is known about the effects of quercetin on atherogenic macrophages. Here, we report that primary bone marrow-derived macrophages internalized less oxidized low-density lipoprotein (oxLDL) and accumulated less intracellular cholesterol in the presence of quercetin. This reduction of foam cell formation correlated with reduced surface expression of the oxLDL receptor CD36. Quercetin also targeted the lipopolysaccharide-dependent, oxLDL-independent pathway of lipid droplet formation in macrophages. In oxLDL-stimulated macrophages, quercetin inhibited reactive oxygen species production and interleukin (IL)-6 secretion. In a system that evaluated cholesterol crystal-induced IL-1ß secretion via nucleotide-binding domain and leucine-rich repeat containing protein 3 inflammasome activation, quercetin also exhibited an inhibitory effect. Dyslipidemic apolipoprotein E-deficient mice chronically treated with intraperitoneal quercetin injections had smaller atheromatous lesions, reduced lipid deposition, and less macrophage and T cell inflammatory infiltrate in the aortic roots than vehicle-treated animals. Serum levels of total cholesterol and the lipid peroxidation product malondialdehyde were also reduced in these mice. Our results demonstrate that quercetin interferes with both key proatherogenic activities of macrophages, namely foam cell formation and pro-oxidant/proinflammatory responses, and these effects may explain the atheroprotective properties of this common flavonoid.


Assuntos
Antioxidantes/farmacologia , Aterosclerose/patologia , Aterosclerose/prevenção & controle , Macrófagos/patologia , Quercetina/farmacologia , Animais , Apolipoproteínas E/genética , Antígenos CD36/biossíntese , Antígenos CD36/genética , Colesterol/metabolismo , LDL-Colesterol/metabolismo , Citocinas/metabolismo , Dieta , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Células Espumosas/metabolismo , Humanos , Inflamação/patologia , Metabolismo dos Lipídeos/genética , Metabolismo dos Lipídeos/fisiologia , Macrófagos/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Oxirredução , Espécies Reativas de Oxigênio/metabolismo
3.
Colomb. med ; 41(4): 358-366, oct.-dic. 2010. tab, graf, ilus
Artigo em Inglês | LILACS | ID: lil-573030

RESUMO

Introduction: Loss of Heterozygocity (LOH) in the short arm of human chromosome 3 (3p) is a frequent event in different types of sporadic tumors, including lung cancer (LC). Aim: To determine 3p LOH in LC samples using 17 microsatellite markers. Methodology: In a pilot study on volunteers, thirteen LC biopsies (tumor tissue) and 4 ml of blood (normal tissue) from the same patient were collected. DNA extraction and Polymerase Chain Reaction (PCR) were performed with 17 microsatellite markers to analyze LOH. Amplified fragments were run on 6% denaturalizing polyacrilamide gels and were visualized by using silver stain. Descriptive analysis was performed for each region on the 3p chromosome. Results: All tumors were informative for one or more of the analyzed markers. LOH was found in one or more loci in eleven samples (84.6%). The markers with major LOH were UBE1L (23.1%), D3S1317, D3S1300, D3S1284, D3S1274, D3S3049, and D3S1577 (15.4%). Three samples showed microsatellite instability (changes in the length of the microsatellite) in different loci. The percentages of LOH for the regions of 3p were: 17.6 % for 3p24-25, 11.62% for 3p21-22, 20% for 3p13-14, and 18.42% for the 3p12 region. Conclusions: Chromosomal regions with allelic loss were identified where probably other GSTs involved in the development of the LC are localized. It should increases sample size and marker number in order to narrow a minimal region and to identify a unknown gene involved in LC.


Introducción: La pérdida de heterocigocidad (LOH) en el brazo corto del cromosoma 3 (3p) humano es un evento frecuente en diferentes tipos de tumores esporádicos, incluyendo cáncer de pulmón (CP). Objetivo: Determinar la LOH de 3p en muestras de CP, con 17 marcadores microsatelitales. Metodología: En un estudio piloto en voluntarios, se recolectaron 13 biopsias de CP (tejido tumoral) y 4 ml de sangre periférica (tejido normal) del mismo paciente, se extrajo el ADN y se realizaron reacciones en cadena de la polimerasa (PCR) con 17 marcadores microsatelitales para analizar LOH. Los fragmentos amplificados se corrieron en geles de poliacrilamida desnaturalizante al 6% y se visualizaron por medio de la coloración de tinción de plata. El análisis descriptivo se realizó para cada región estudiada en el cromosoma 3p. Resultados: Todos los tumores fueron informativos para uno o más de los marcadores analizados. Se encontró LOH en uno o más loci en 11 muestras (84.6%). Los marcadores con mayores LOH fueron UBE1L (23.1%), D3S1317, D3S1300, D3S1284, D3S1274, D3S3049 y D3S1577 con 15.4%. Tres muestras presentaron inestabilidad microsatelital (cambios en la longitud del microsatélite) en diferentes loci. Los porcentajes de LOH para las regiones de 3p fueron: 17.6 % para 3p24-25, 11.6% para 3p21-22, 20% para 3p13-14 y 18.4% para la región 3p12. Conclusiones: Se identificaron regiones cromosómicas con pérdida alélica donde es probable que se localicen otros GST involucrados en el desarrollo de CP, diferentes de los ya identificados como VHL, RASSF1A, FHIT y DUTTI, entre otros. Se debe aumentar el número de muestras y de marcadores para delimitar una región mínima e identificar algún gen no descrito implicado en la carcinogénesis de pulmón.


Assuntos
Humanos , Perda de Heterozigosidade , Neoplasias Pulmonares , Reação em Cadeia da Polimerase
4.
Rev Alerg Mex ; 54(4): 140-3, 2007.
Artigo em Espanhol | MEDLINE | ID: mdl-18297854

RESUMO

We report an anaphylactic shock case secondary to propofol and fentanyl exposition, demonstrated by skin tests. A male patient, 19 years old, was admitted in the operating room for resection of residual juvenile nasal angyofibroma. The anesthetic induction was done with atropin 800 microg, midazolam 2 mg, fentanyl 200 microg, propofol 150 mg, and neuromuscular block with rocuronium 30 mg. One minute after the application of drugs, hypotension of 60/30 mmHg and tachycardia of 130 was observed. By the second minute the blood pressure dropped to 40/20 mmHg, tachycardia got 135, facial edema and generalized wheals occurred and the plestimography and oxymetry record were absent. Once resolved the event and the patient recovered, skin tests were performed with positive results to propofol and fentanyl, so that they were excluded in the next surgical intervention that concluded without incidents and with success.


Assuntos
Anafilaxia/induzido quimicamente , Anestésicos Intravenosos/efeitos adversos , Fentanila/efeitos adversos , Propofol/efeitos adversos , Adulto , Humanos , Masculino
5.
Rev. colomb. radiol ; 16(3): 1788-1790, sept. 2005. ilus
Artigo em Espanhol | LILACS | ID: lil-521525

RESUMO

La histoplasmosis es una micosis de origen pulmonar primario, adquirida por vía inhalatoria. En la mayoría de los casos, la infección pasa inadvertida o se manifiesta por síntomas respiratorios leves. El histoplasmoma es una forma relativamente común de histoplasmosis pulmonar aguda, de aspecto nodular, generalmente acompañada de calcificación, la cual puede aumentar en tamaño y simular una neoplasia pulmonar. presenta un caso de un paciente inmunosuprimido con esta forma de micosis pulmonar.


Assuntos
Humanos , Histoplasmose , Pneumopatias Fúngicas , Micoses , Radiografia Torácica
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