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1.
Biotechnol Rep (Amst) ; 27: e00519, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32874946

RESUMO

Plant cell suspension culture of T. peruviana is a feasible biotechnological platform for the production of secondary metabolites with anti-proliferative/cytotoxic activity, as phenolic compounds (PC); however, different in in vitro growth conditions may affect the production, demanding strategies to increase the metabolite biosynthesis, as well as the development of sensitive and rapid analytical methods for metabolite monitoring. The Fourier transform near-infrared (FT-NIR) spectroscopy and Reversed-phase high-performance liquid chromatography (RP-HPLC) combined with Multivariate analysis (MVA) were used to detect significant differences in the PC production in cultures treated with two elicitors. The results suggest that the FT-NIR-MVA is useful for discriminating samples according to the treatment, showed significant influence of the PC signal. RP-HPLC-MVA showed that the elicitor effect occurs at 72 h post-elicitation. Detection of dihydroquercetin (maximum concentration = 12.59 mg/L), a flavonoid with anti-cancer properties, is highlighted. Future studies will be aimed at scaling this culture to increase the productivity of dihydroquercetin.

2.
Braz. arch. biol. technol ; Braz. arch. biol. technol;63: e20180735, 2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1132190

RESUMO

Abstract Thevetia peruviana is an ornamental shrub grown-up in many tropical region of the world. This plant produces secondary metabolites with biological properties of interest for the pharmaceutical industry. The objective was to determine the secondary metabolites profile of callus and cell suspension cultures of T. peruviana and compare them with those from explant (fruit pulp). Extracts in 50% aqueous ethanol and ethyl acetate were prepared. The phytochemical analysis was performed using standard chemical tests and thin layer chromatography. In addition, total phenolic and flavonoids compounds (TPC and TFC), total cardiac glycosides (TCG) and total antioxidant activity (TAA) was determined during the cell suspension growth. Phenolic chemical profile was also analyzed by high performance liquid chromatography (HPLC). Common metabolites (alkaloids, amino acids, antioxidants, cardiac glycosides, leucoanthocyanidins, flavonoids, phenols, sugars and triterpenes) were detected in all samples. The maximum production of extracellular TCG, TPC, TFC and TAA in cells suspensions were at 6-12 days; in contrast, intracellular content was relatively constant during the exponential grown phase (0 to 12-days). HPLC analysis detected one compound with retention time at 11.6 min; this compound was tentatively identified as dihydroquercetin, a flavonoid with anti-cancer properties. These results provide evidence on the utility of the in vitro cell cultures of T. peruviana for valuable pharmaceutical compounds production.


Assuntos
Células Cultivadas , Thevetia/citologia , Compostos Fitoquímicos/biossíntese , Triterpenos , Flavonoides , Cromatografia Líquida de Alta Pressão , Anticarcinógenos , Thevetia/química , Técnicas de Cultura , Compostos Fitoquímicos/análise , Antioxidantes
3.
J Immunol Methods ; 464: 15-21, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30165063

RESUMO

Conjugation of avian IgY antibodies to nanosensors has been extensively explored for the diagnostics of virus and parasite infection, as well as for the detection of pharmaceutically and toxicologically relevant molecules. However, to date this strategy has only been minimally applied the detection of allergens. In this study, gold nanoparticles (GNPs) were conjugated to a polyvalent IgY antibodies raised against Dermatophagoides group I allergens. GNPs were synthesized by HAuCL4 reduction using 1% trisodium citrate, and characterized them by absorption spectroscopy and transmission electron microscopy (TEM). The most stable immunoconjugates were obtained with 18-nm monodisperse GNPs and a minimal concentration of 12.5 µg/mL of IgY at pH 7.5. The immunoconjugate was capable of detecting up to 1.5 µg of a total Dermatophagoides farinae protein extract in an immuno-dot blot assay. This immunoreactant conjugate represents a new tool for the detection and control of indoor dust mite allergens.


Assuntos
Antígenos de Dermatophagoides/sangue , Proteínas de Artrópodes/sangue , Cloretos , Cisteína Endopeptidases/sangue , Dermatophagoides farinae/imunologia , Compostos de Ouro , Hipersensibilidade/diagnóstico , Immunoblotting , Imunoconjugados , Nanopartículas Metálicas , Nanomedicina/métodos , Animais , Biomarcadores/sangue , Humanos , Hipersensibilidade/sangue , Hipersensibilidade/imunologia , Imunoglobulinas , Valor Preditivo dos Testes , Reprodutibilidade dos Testes
4.
Biomedica ; 38(2): 232-243, 2018 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-30184353

RESUMO

Introduction: The use of specific antibodies capable of detecting allergens of the group 1 of house dust mites represents a potential strategy to reduce exposure and clinical symptomatology associated with asthma and allergic rhinitis. Objective: To produce and purify chicken antibodies specific for the dust mites Dermatophagoides sp. and B. tropicalis using the IgY technology. Materials and methods: We designed and synthesized oligopeptides showing immunogenic epitopes of Der p1, Der f1, and Blo t1. These were used to produce IgY antibodies in Hy Line Brown chickens. IgY were extracted from egg yolk using thiophilic chromatography. The immunogenicity and specificity were assayed by indirect ELISA and Dot Blot. Results: We obtained high reactivity of IgY antibodies against epitopes of allergens present in whole body mites extracts of D. farinae, D. pteronyssinus, and B. tropicalis. The highest IgY levels were registered between days 32 and 40 after immunization. The antibodies showed high immunoreactivity and specificity towards D. farinae proteins with detection limits above 0.03 µg of mite proteins under the experimental conditions used. Purified IgY did not show significant reactivity when binding to Periplaneta americana extract. Conclusion: The IgY technology allowed the production of specific antibodies against house dust mites group 1 allergens using non-glycosylated synthetic peptides. To our knowledge, this is the first time that this immunochemicals are used in the detection of mites of medical relevance.


Assuntos
Anticorpos/imunologia , Antígenos de Dermatophagoides/imunologia , Imunoglobulinas/imunologia , Oligopeptídeos/imunologia , Pyroglyphidae/imunologia , Animais , Galinhas
5.
Biotechnol Rep (Amst) ; 19: e00273, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29998072

RESUMO

The objective was to enhance the production of the phenolic compounds in plant cell suspension cultures of T. peruviana at shake flask scale. The effects of salicylic acid (SA), methyl-jasmonate (MeJA) and the combination of both (SA/MeJA) were studied. Elicitor concentration, elicitation time and harvest time of cells were optimized. Phenolic compound content (PCC), flavonoid content (FC) and antioxidant activity (AA) were determined by the folin-ciocalteu method, flavonoid-aluminum complexation method and the ABTS assay, respectively. Differences between intracellular metabolite profiles due to the mentioned treatments were analyzed by Thin-layer chromatography and High-performance liquid chromatography. Highest PCC, FC and AA were obtained under the following treatments: 3 µM MeJA > 3 µM MeJA/300 µM SA > 300 µM SA > control, when elicited on the 4th day and harvested 96-h post-elicitation. It was demonstrated that exposure to 3 µM MeJA increase 1.49-fold of PCC, 1.66-fold of AA and 2.55-fold of FC compared to the control culture.

6.
Biomédica (Bogotá) ; Biomédica (Bogotá);38(2): 232-243, ene.-jun. 2018. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-950942

RESUMO

Resumen Introducción. La obtención de anticuerpos específicos capaces de detectar alérgenos del grupo 1 de ácaros del polvo doméstico representa una estrategia potencial de salud pública para reducir la exposición y la sintomatología clínica asociada con el asma y la rinitis alérgica. Objetivo. Producir y purificar anticuerpos aviares antialérgenos específicos del grupo 1 de los ácaros Dermatophagoides sp.y Blomia tropicalis utilizando la tecnología IgY. Materiales y métodos. Se diseñaron y sintetizaron oligopéptidos que evidenciaran epítopes inmunogénicos de los alérgenos Der p1, Der f1 y Blo t1 empleados posteriormente para producir anticuerpos IgY policlonales en gallinas Hy Line Brown. Las IgY presentes en las yemas de los huevos se purificaron mediante cromatografía tiofílica. Su inmunorreactividad y especificidad se determinaron mediante un inmunoensayo ELISA indirecto y Dot Blot. Resultados. Se obtuvo una reactividad elevada de las IgY contra epítopes de alérgenos presentes en extractos de cuerpo entero de D. farinae, D. pteronyssinus y B. tropicalis. Los niveles más altos de IgY se produjeron entre los días 32 y 40 de inmunización. Los anticuerpos mostraron mayor inmunorreactividad y especificidad en el reconocimiento de proteínas de D. farinae, con un límite de detección mayor de 0,03 µg de proteína total delcaroajo las condiciones experimentales analizadas. Las IgY purificadas no mostraron reactividad significativa frente al extracto de Periplaneta americana. Conclusión. La tecnología IgY permitió la producción de anticuerpos específicos contra alérgenos del grupo 1 de los ácaros del polvo al utilizar oligopéptidos sintéticos no glicosilados. Hasta donde se sabe, esta es la primera vez que se usan estos reactivos inmunológicos para la detección de ácaros de importancia médica.


Abstract Introduction: The use of specific antibodies capable of detecting allergens of the group 1 of house dust mites represents a potential strategy to reduce exposure and clinical symptomatology associated with asthma and allergic rhinitis. Objective: To produce and purify chicken antibodies specific for the dust mites Dermatophagoides sp. and B. tropicalis using the IgY technology. Materials and methods: We designed and synthesized oligopeptides showing immunogenic epitopes of Der p1, Der f1, and Blo t1. These were used to produce IgY antibodies in Hy Line Brown chickens. IgY were extracted from egg yolk using thiophilic chromatography. The immunogenicity and specificity were assayed by indirect ELISA and Dot Blot. Results: We obtained high reactivity of IgY antibodies against epitopes of allergens present in whole body mites extracts of D. farinae, D. pteronyssinus, and B. tropicalis. The highest IgY levels were registered between days 32 and 40 after immunization. The antibodies showed high immunoreactivity and specificity towards D. farinae proteins with detection limits above 0.03 µg of mite proteins under the experimental conditions used. Purified IgY did not show significant reactivity when binding to Periplaneta americana extract. Conclusion: The IgY technology allowed the production of specific antibodies against house dust mites group 1 allergens using non-glycosylated synthetic peptides. To our knowledge, this is the first time that this immunochemicals are used in the detection of mites of medical relevance.


Assuntos
Animais , Oligopeptídeos/imunologia , Imunoglobulinas/imunologia , Pyroglyphidae/imunologia , Antígenos de Dermatophagoides/imunologia , Anticorpos/imunologia , Galinhas
7.
Rev Alerg Mex ; 63(3): 252-69, 2016.
Artigo em Espanhol | MEDLINE | ID: mdl-27560913

RESUMO

BACKGROUND: Asthma is a common disease in the world and vitamin D (Vit-D) has been associated with the presence and severity of this disease. OBJECTIVE: To establish the association between levels of Vit-D and IgE response in schoolchildren with asthma living in four cities in Colombia. METHODS: Case-control study in 1340 schoolchildren (687 asthmatic and 653 controls) from communities in extreme poverty in Barranquilla, Cartagena, Santa Marta, and Montería. Serum concentrations of Vit-D, total IgE, and anti-Dermatophagoides farinae, Periplaneta americana, and Ascaris lumbricoides (AL) specific IgE were measured. RESULTS: Controls reported higher concentrations of Vit-D [61.9 ± 28.4 ng/mL] than cases [53 ± 23.3 ng / mL] (p < 0.05). Total IgE was higher in cases (p < 0.05). Only anti-AL IgE showed a clear difference: in controls, optical density was 0.27 ± 0.25; in cases, 0.22 ± 0.24 (p < 0.05). Vit-D showed differences between cases and controls in each population. CONCLUSIONS: An association could not be demonstrated between Vit-D deficiency and asthma, as total IgE was elevated in patients and controls. The results suggest that Vit-D influences the specif IgE response in poor asthmatic children in areas endemic for helminthiasis.


Antecedentes: El asma es una enfermedad frecuente en el mundo y la vitamina D (Vit-D) se ha asociado con la presencia y severidad de esta enfermedad. Objetivo: Establecer la asociación entre los niveles de Vit-D y la respuesta IgE en escolares con asma residentes de cuatro ciudades colombiananas. Métodos: Estudio de casos y controles en 1340 escolares (687 asmáticos y 653 controles) de comunidades en extrema pobreza de Barranquilla, Cartagena, Santa Marta y Montería. Se midieron las concentraciones séricas de Vit-D, IgE total e IgE específica anti Dermatofagoides farinae, Periplaneta americana y Ascaris lumbricoides (AL). Resultados: Los controles reportaron concentraciones mayores de Vit-D [61.9 ± 28.4 ng/mL] que los casos [53 ± 23.3 ng/mL] (p<0.05). La IgE total fue mayor en los casos (p<0.05). Solo IgE anti-AL mostró una diferencia clara: controles, densidad óptica 0.27 ± 0.25; casos 0.22 ± 0.24 (p<0.05). La Vit-D presentó diferencias entre casos y controles en cada población. Conclusiones: No se pudo demostrar la asociación entre deficiencia de Vit-D y asma, dado que la IgE total estuvo elevada en los pacientes y en los controles. Los resultados sugieren que la Vit-D influye en la respuesta IgE específica en niños asmáticos pobres en zonas endémicas para helmintiasis.


Assuntos
Asma/sangue , Asma/imunologia , Imunoglobulina E/imunologia , Áreas de Pobreza , Deficiência de Vitamina D/imunologia , Vitamina D/sangue , Alérgenos , Animais , Ascaris lumbricoides/imunologia , Estudos de Casos e Controles , Criança , Colômbia , Dermatophagoides farinae/imunologia , Humanos , Imunoglobulina E/sangue , Periplaneta/imunologia
8.
Biomedica ; 22(3): 241-52, 2002 Sep.
Artigo em Espanhol | MEDLINE | ID: mdl-12404924

RESUMO

A cDNA library of Plasmodium falciparum (Colombian strain FCB2) asexual stage was constructed in the lambda ZipLox vector. The lambda ZipLox library and a lambda ZAPII (Dd2 strain) were screened for genes coding for proteins that bind with or are related to calmodulin (CaM). Screening was accomplished with Hot start PCR assays and hybridization with radiolabeled probes. Actin I, CaM, glutamate synthase (GOGAT) and the three myosin clones--Pfmyo A, Pfmyo B and Pfmyo C--were identified. The clones coding for actin I, CaM and GOGAT were retrieved from the lambda ZipLox library, and the GOGAT and Pfmyo A clones from the lambda ZAP II library. The GOGAT clone contained an insert of 2,413 base pairs corresponding to 24.8% of the reported sequence. The Pfmyo A insert was 2,457 base pairs long, and represented the complete mRNA coding for this gene. Finally, the first report of a complete cDNA clone containing the P. falciparum myosin A is presented.


Assuntos
Proteínas de Ligação a Calmodulina/genética , Biblioteca Gênica , Glutamato Sintase/genética , Miosinas/genética , Plasmodium falciparum/genética , Animais
9.
Biomédica (Bogotá) ; Biomédica (Bogotá);22(3): 241-252, sep. 2002.
Artigo em Espanhol | LILACS | ID: lil-330484

RESUMO

A cDNA library of Plasmodium falciparum (Colombian strain FCB2) asexual stage was constructed in the lambda ZipLox vector. The lambda ZipLox library and a lambda ZAPII (Dd2 strain) were screened for genes coding for proteins that bind with or are related to calmodulin (CaM). Screening was accomplished with Hot start PCR assays and hybridization with radiolabeled probes. Actin I, CaM, glutamate synthase (GOGAT) and the three myosin clones--Pfmyo A, Pfmyo B and Pfmyo C--were identified. The clones coding for actin I, CaM and GOGAT were retrieved from the lambda ZipLox library, and the GOGAT and Pfmyo A clones from the lambda ZAP II library. The GOGAT clone contained an insert of 2,413 base pairs corresponding to 24.8 of the reported sequence. The Pfmyo A insert was 2,457 base pairs long, and represented the complete mRNA coding for this gene. Finally, the first report of a complete cDNA clone containing the P. falciparum myosin A is presented.


Assuntos
Animais , Proteínas de Ligação a Calmodulina , Biblioteca Gênica , Glutamato Sintase , Miosinas , Plasmodium falciparum
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