Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 9 de 9
Filtrar
Más filtros











Intervalo de año de publicación
1.
Methods Mol Biol ; 2775: 359-365, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38758329

RESUMEN

Extracellular vesicles (EVs) are produced by all domains of life. In fungal pathogens, they participate in virulence mechanisms and/or induce protective immunity, depending on the pathogenic species. EVs produced by pathogenic members of the Cryptococcus genus mediate virulence, antifungal resistance, as well as humoral and cell-mediated immunity. The isolation of cryptococcal EVs has been laborious and time-consuming for years. In this chapter, we detail a fast protocol for the isolation and analysis of EVs produced by members of the Cryptococcus genus.


Asunto(s)
Cryptococcus , Vesículas Extracelulares , Vesículas Extracelulares/metabolismo , Criptococosis/microbiología , Criptococosis/inmunología , Humanos
2.
Methods Mol Biol ; 2551: 605-631, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36310228

RESUMEN

Uncontrolled assembly/disassembly of physiologically formed liquid condensates is linked to irreversible aggregation. Hence, the quest for understanding protein-misfolding disease mechanism might lie in the studies of protein:nucleic acid coacervation. Several proteins with intrinsically disordered regions as well as nucleic acids undergo phase separation in the cellular context, and this process is key to physiological signaling and is related to pathologies. Phase separation is reproducible in vitro by mixing the target recombinant protein with specific nucleic acids at various stoichiometric ratios and then examined by microscopy and nanotracking methods presented herein. We describe protocols to qualitatively assess hallmarks of protein-rich condensates, characterize their structure using intrinsic and extrinsic dyes, quantify them, and analyze their morphology over time. Analysis by nanoparticle tracking provides information on the concentration and diameter of high-order protein oligomers formed in the presence of nucleic acid. Using the model protein (globular domain of recombinant murine PrP) and DNA aptamers (high-affinity oligonucleotides with 25 nucleotides in length), we provide examples of a systematic screening of liquid-liquid phase separation in vitro.


Asunto(s)
Aptámeros de Nucleótidos , Proteínas Intrínsecamente Desordenadas , Nanopartículas , Ácidos Nucleicos , Ratones , Animales , Microscopía , Proteínas Recombinantes , Proteínas Intrínsecamente Desordenadas/química
3.
Int. j. high dilution res ; 20(4): 11-28, Dec. 31, 2021.
Artículo en Inglés | LILACS, HomeoIndex - Homeopatia | ID: biblio-1396371

RESUMEN

Homeopathy is highly controversial. The main reason for this is its use of very highly dilute medicines (high homeopathic potencies, HHP), diluted beyond the Avogadro/Loschmidt limit. Research using several different methods has demonstrated the presence of particles, including nanoparticles of source material, in HHPs. This study aims to verify the results of a previous publication that detected the presence of particles in all dilutions. We used the Nano Tracking Analyzer (NTA) to examine dilutions of a commonly used homeopathic medicine, an insoluble metal, Cuprum metallicum, for the presence of particles. The homeopathic medicines tested were specially prepared according to the European pharmacopoeia standards. We compared the homeopathic dilutions/dynamizations with simple dilutions and controls including a soluble medicine. We observed the presence of solid material in all preparations including HHPs (except for pure water). The measurements showed significant differences in particle sizes distribution between homeopathic manufacturing lines and controls. Homeopathic medicines do contain material with a specific size distribution even in HHPs diluted beyond the Avogadro/Loschmidt limit. This specificity can be attributed to the manufacturing and potentization process. This material demonstrates that the step-by-step process (dynamized or not) does not match the theoretical expectations in a dilution process. The starting material and dilution/dynamization method influences the nature and concentration of these NPs.


Asunto(s)
Dinamización , Farmacotécnica Homeopática , Nanopartículas , Cloruro de Potasio , Cuprum , Kali Muriaticum , Cobre , Lactosa
4.
Artículo en Inglés | MEDLINE | ID: mdl-32528536

RESUMEN

BACKGROUND: Extracellular vesicles (EVs) are small membrane-bound vesicles of growing interest in vetetinary parasitology. The aim of the present report was to provide the first isolation, quantification and protein characterization of EVs from buffalo (Bubalus bubalis) sera infected with Theileria spp. METHODS: Infected animals were identified through optical microscopy and PCR. EVs were isolated from buffalo sera by size-exclusion chromatography and characterized using western blotting analysis, nanoparticle tracking analysis and transmission electron microscopy. Subsequently, the proteins from isolated vesicles were characterized by mass spectrometry. RESULTS: EVs from buffalo sera have shown sizes in the 124-140 nm range and 306 proteins were characterized. The protein-protein interaction analysis has evidenced biological processes and molecular function associated with signal transduction, binding, regulation of metabolic processes, transport, catalytic activity and response to acute stress. Five proteins have been shown to be differentially expressed between the control group and that infected with Theileria spp., all acting in the oxidative stress pathway. CONCLUSIONS: EVs from buffaloes infected with Theileria spp. were successfully isolated and characterized. This is an advance in the knowledge of host-parasite relationship that contributes to the understanding of host immune response and theileriosis evasion mechanisms. These findings may pave the way for searching new EVs candidate-markers for a better production of safe biological products derived from buffaloes.

5.
J. Venom. Anim. Toxins incl. Trop. Dis. ; 26: e20190067, May 29, 2020. ilus, tab, graf
Artículo en Inglés | VETINDEX | ID: vti-29964

RESUMEN

Background: Extracellular vesicles (EVs) are small membrane-bound vesicles of growing interest in vetetinary parasitology. The aim of the present report was to provide the first isolation, quantification and protein characterization of EVs from buffalo (Bubalus bubalis) sera infected with Theileria spp. Methods: Infected animals were identified through optical microscopy and PCR. EVs were isolated from buffalo sera by size-exclusion chromatography and characterized using western blotting analysis, nanoparticle tracking analysis and transmission electron microscopy. Subsequently, the proteins from isolated vesicles were characterized by mass spectrometry. Results: EVs from buffalo sera have shown sizes in the 124-140 nm range and 306 proteins were characterized. The protein-protein interaction analysis has evidenced biological processes and molecular function associated with signal transduction, binding, regulation of metabolic processes, transport, catalytic activity and response to acute stress. Five proteins have been shown to be differentially expressed between the control group and that infected with Theileria spp., all acting in the oxidative stress pathway. Conclusions: EVs from buffaloes infected with Theileria spp. were successfully isolated and characterized. This is an advance in the knowledge of host-parasite relationship that contributes to the understanding of host immune response and theileriosis evasion mechanisms. These findings may pave the way for searching new EVs candidate-markers for a better production of safe biological products derived from buffaloes.(AU)


Asunto(s)
Animales , Masculino , Búfalos/parasitología , Vesículas Extracelulares/química , Theileria , Búfalos/sangre , Proteoma/análisis , Nanopartículas/análisis , Infecciones por Protozoos
6.
J. venom. anim. toxins incl. trop. dis ; J. venom. anim. toxins incl. trop. dis;26: e20190067, 2020. tab, graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1135161

RESUMEN

Extracellular vesicles (EVs) are small membrane-bound vesicles of growing interest in vetetinary parasitology. The aim of the present report was to provide the first isolation, quantification and protein characterization of EVs from buffalo (Bubalus bubalis) sera infected with Theileria spp. Methods: Infected animals were identified through optical microscopy and PCR. EVs were isolated from buffalo sera by size-exclusion chromatography and characterized using western blotting analysis, nanoparticle tracking analysis and transmission electron microscopy. Subsequently, the proteins from isolated vesicles were characterized by mass spectrometry. Results: EVs from buffalo sera have shown sizes in the 124-140 nm range and 306 proteins were characterized. The protein-protein interaction analysis has evidenced biological processes and molecular function associated with signal transduction, binding, regulation of metabolic processes, transport, catalytic activity and response to acute stress. Five proteins have been shown to be differentially expressed between the control group and that infected with Theileria spp., all acting in the oxidative stress pathway. Conclusions: EVs from buffaloes infected with Theileria spp. were successfully isolated and characterized. This is an advance in the knowledge of host-parasite relationship that contributes to the understanding of host immune response and theileriosis evasion mechanisms. These findings may pave the way for searching new EVs candidate-markers for a better production of safe biological products derived from buffaloes.(AU)


Asunto(s)
Animales , Búfalos/microbiología , Enfermedades Transmisibles , Theileria , Nanopartículas , Vesículas Extracelulares , Fenómenos Biológicos , Proteómica
7.
Front Immunol ; 9: 2343, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30356863

RESUMEN

The release of biomolecules critically affects all pathogens and their establishment of diseases. For the export of several biomolecules in diverse species, the use of extracellular vesicles (EVs) is considered to represent an alternative transport mechanism, but no study to date has investigated EVs from dermatophytes. Here, we describe biologically active EVs from the dermatophyte Trichophyton interdigitale, a causative agent of mycoses worldwide. EV preparations from T. interdigitale were examined using nanoparticle-tracking analysis, which revealed vesicular structures 20-380 nm in diameter. These vesicles induced the production of proinflammatory mediators by bone marrow-derived macrophages (BMDMs) and keratinocytes in a dose-dependent manner, and an addition of the EVs to BMDMs also stimulated the transcription of the M1-polarization marker iNOS (inducible nitric oxide synthase) and diminished the expression of the M2 markers arginase-1 and Ym-1. The observed M1 macrophages' polarization triggered by EVs was abolished in cells obtained from knockout Toll-like receptor-2 mice. Also, the EVs-induced productions of pro-inflammatory mediators were blocked too. Furthermore, the EVs from T. interdigitale enhanced the fungicidal activity of BMDMs. These results suggest that EVs from T. interdigitale can modulate the innate immune response of the host and influence the interaction between T. interdigitale and host immune cells. Our findings thus open new areas of investigation into the host-parasite relationship in dermatophytosis.


Asunto(s)
Vesículas Extracelulares/metabolismo , Queratinocitos/inmunología , Queratinocitos/metabolismo , Macrófagos/inmunología , Macrófagos/metabolismo , Tiña/inmunología , Tiña/microbiología , Trichophyton/inmunología , Trichophyton/metabolismo , Animales , Biomarcadores , Citocinas/metabolismo , Modelos Animales de Enfermedad , Inmunomodulación , Inmunofenotipificación , Mediadores de Inflamación/metabolismo , Activación de Macrófagos/inmunología , Macrófagos/microbiología , Masculino , Ratones , Ratones Noqueados , Óxido Nítrico/metabolismo , Fagocitosis/inmunología
8.
Methods Mol Biol ; 1459: 161-74, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27665558

RESUMEN

This chapter is derived from our experience in the study of stress-Inducible Protein 1 (STI1) in extracellular vesicles. We used different techniques to isolate, explore, and characterize the extracellular vesicles that contained this protein. Ultracentrifugation and gel chromatography were used to isolate extracellular vesicles of different sizes, nanotracking particle analysis (NTA) determined number and size of vesicles, while flow cytometry and ELISA were used to determine the specific protein content of vesicles.


Asunto(s)
Vesículas Extracelulares/metabolismo , Proteínas de Choque Térmico/metabolismo , Fraccionamiento Celular , Cromatografía en Gel , Ensayo de Inmunoadsorción Enzimática , Citometría de Flujo , Transporte de Proteínas , Ultracentrifugación
9.
J Negat Results Biomed ; 15: 7, 2016 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-27063005

RESUMEN

BACKGROUND: Patients with severe aortic stenosis have increased levels of prothrombotic and proinflammatory microparticles (MP), and MPs actively regulate pathological processes that lead to atherothrombotic cardiovascular events. Shear stress is a validated stimulus of MP production, and abnormal shear stress in aortic stenosis increases MP release in ex-vivo studies. We hypothesized that in patients with severe aortic stenosis, percutaneous replacement of the aortic valve (TAVR) would reduce abnormal shear stress and would decrease levels of circulating MPs. FINDINGS: The experimental protocol utilized flow cytometry (FC) and nanoparticle tracking analysis (NTA) to quantify circulating plasma MP levels in aortic stenosis patients at baseline and 5 days after TAVR. The baseline and 5 day MP counts measured by FC were 6.10⋅10(5) ± 1.21⋅10(5) MP/µL and 5.74⋅10(5) ± 9.54⋅10(4) MP/µL, respectively (p = 0.91). The baseline and 5 day MP counts measured by NTA were 9.29⋅10(13) ± 1.66⋅10(13) MP/µL and 3.95⋅10(14) ± 3.11⋅10(14) MP/µL, respectively (p = 0.91). When MPs were stratified by cell source, there was no difference in pre/post TAVR endothelial, platelet, or leukocyte MP levels. CONCLUSION: Levels of circulating MPs do not change acutely following TAVR therapy for aortic stenosis. Trial registered at clinicaltrials.gov NCT02193035 on July 11, 2014.


Asunto(s)
Válvula Aórtica/cirugía , Plaquetas/química , Endotelio Vascular/química , Prótesis Valvulares Cardíacas , Macrófagos/química , Reemplazo de la Válvula Aórtica Transcatéter , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA