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1.
An Acad Bras Cienc ; 94(4): e20210190, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36228216

RESUMEN

Duchenne muscular dystrophy (DMD) is a severe disease with no cure caused by a genetic abnormality, promoting progressive muscle degeneration. Corticosteroids are used drugs in treatment associated with adverse effects. The extract of Miconia ferruginata (Melastomataceae) (MF) has demonstrated potent antioxidant and anti-inflammatory potential in vitro. This study used a DMD model (mdx) to determine the toxic dose of this plant and found a possible non-toxic dose with therapeutic effects. The mdx groups received an intraperitoneal injection of 0 (control group), 50, 100, 200, 300, and 2000 mg kg-1 of the aqueous leaf extract following a single-dose acute toxicity protocol and were observed for 14 days. The range of toxicity of the extract and LD50 were determined. Histopathological analysis, the quantification of fibrosis, and immunohistochemical analysis of the tissues were performed. The results demonstrated that 2000 mg kg-1 was highly toxic, inducing histopathological changes in the tissues evaluated, with 100% mortality in 48 hours. The other doses caused no behavioral changes or signs of toxicity. The MF extract led reduction in histopathological changes, fibrosis, and inflammation, a reduction in HSP70 and an increase in MCL-1 proteins. Doses of 50-200 mg kg-1 demonstrated regenerative tissue and anti-inflammatory potential.


Asunto(s)
Melastomataceae , Distrofia Muscular de Duchenne , Animales , Antiinflamatorios/farmacología , Antiinflamatorios/uso terapéutico , Antioxidantes/metabolismo , Modelos Animales de Enfermedad , Fibrosis , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos mdx , Músculo Esquelético/metabolismo , Distrofia Muscular de Duchenne/tratamiento farmacológico , Proteína 1 de la Secuencia de Leucemia de Células Mieloides/metabolismo , Proteína 1 de la Secuencia de Leucemia de Células Mieloides/uso terapéutico , Extractos Vegetales/metabolismo , Extractos Vegetales/uso terapéutico , Extractos Vegetales/toxicidad
2.
Talanta ; 195: 327-332, 2019 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-30625550

RESUMEN

Leishmaniasis is a disease with high impact on public health in many countries. Visceral leishmaniasis (VL) is a vectorial zoonosis, with dogs as primary reservoirs in the domestic environment. VL presents high morbidity, mortality and importance in epidemiology in the American continent. In the present study, the first label-free electrochemical impedance immunosensor using screen-printed electrodes (SPEs) for the detection of anti-Leishmania infantum antibodies was developed. The soluble antigens of L. infantum were immobilized on an SPE by a 3-mercaptopropionic acid monolayer. Electrochemical impedance spectroscopy (EIS) was used for detecting bimolecular interactions occurring at the electrode surface. The addition of real samples consisting of canine and human sera positive and negative for VL presented high sensitivity and selectivity through EIS. Based on the results, a sensitive, specific, rapid and simple immunosensor was developed successfully with potential application for the serological diagnosis of leishmaniasis disease.


Asunto(s)
Anticuerpos Antiprotozoarios/sangre , Técnicas Biosensibles , Enfermedades de los Perros/diagnóstico , Leishmania infantum/inmunología , Leishmaniasis Visceral/diagnóstico , Animales , Anticuerpos Antiprotozoarios/inmunología , Antígenos de Protozoos/química , Antígenos de Protozoos/inmunología , Espectroscopía Dieléctrica , Enfermedades de los Perros/sangre , Enfermedades de los Perros/inmunología , Perros , Electrodos , Oro/química , Humanos , Inmunoensayo , Leishmaniasis Visceral/sangre , Leishmaniasis Visceral/inmunología , Leishmaniasis Visceral/veterinaria
3.
Amino Acids ; 49(8): 1389-1400, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28573520

RESUMEN

This work proposes a strategy that uses solid-phase peptide synthesis associated with copper(I)-catalyzed azide alkyne cycloaddition reaction to promote the glycosylation of an antimicrobial peptide (HSP1) containing a carboxyamidated C-terminus (HSP1-NH2). Two glycotriazole-peptides, namely [p-Glc-trz-G1]HSP1-NH2 and [p-GlcNAc-trz-G1]HSP1-NH2, were prepared using per-O-acetylated azide derivatives of glucose and N-acetylglucosamine in the presence of copper(II) sulfate pentahydrate (CuSO4·5H2O) and sodium ascorbate as a reducing agent. In order to investigate the synergistic action of the carbohydrate motif linked to the triazole-peptide structure, a triazole derivative [trz-G1]HSP1-NH2 was also prepared. A set of biophysical approaches such as DLS, Zeta Potential, SPR and carboxyfluorescein leakage from phospholipid vesicles confirmed higher membrane disruption and lytic activities as well as stronger peptide-LUVs interactions for the glycotriazole-peptides when compared to HSP1-NH2 and to its triazole derivative, which is in accordance with the performed biological assays: whereas HSP1-NH2 presents relatively low and [trz-G1]HSP1-NH2 just moderate fungicidal activity, the glycotriazole-peptides are significantly more effective antifungal agents. In addition, the glycotriazole-peptides and the triazole derivative present strong inhibition effects on ergosterol biosynthesis in Candida albicans, when compared to HSP1-NH2 alone. In conclusion, the increased fungicidal activity of the glycotriazole-peptides seems to be the result of (A) more pronounced membrane-disruptive properties, which is related to the presence of a saccharide ring, together with (B) the inhibition of ergosterol biosynthesis, which seems to be related to the presence of both the monosaccharide and the triazole rings.


Asunto(s)
Antifúngicos/farmacología , Bacterias/efectos de los fármacos , Carbohidratos/química , Hongos/efectos de los fármacos , Fragmentos de Péptidos/farmacología , Triazoles/química , Antifúngicos/química , Catálisis , Química Clic , Fragmentos de Péptidos/química , Técnicas de Síntesis en Fase Sólida
4.
Clin Chim Acta ; 454: 39-45, 2016 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-26731593

RESUMEN

BACKGROUND: We defined the methodological criteria for the interpretation of the results provided by a novel immunoassay based on surface plasmon resonance (SPR) to detect antibodies anti-Trypanosoma cruzi in human sera (SPRCruzi). Then, we evaluated its applicability as a diagnostic tool for Chagas disease. METHODS: To define the cut-off point and serum dilution factor, 57 samples were analyzed at SPRCruzi and the obtained values of SPR angle displacement (ΔθSPR) were submitted to statistical analysis. Adopting the indicated criteria, its performance was evaluated into a wide panel of samples, being 99 Chagas disease patients, 30 non-infected subjects and 42 with other parasitic/infectious diseases. In parallel, these samples were also analyzed by ELISA. RESULTS: Our data demonstrated that 1:320 dilution and cut-off point at ∆θSPR=17.2 m° provided the best results. Global performance analysis demonstrated satisfactory sensitivity (100%), specificity (97.2%), positive predictive value (98%), negative predictive value (100%) and global accuracy (99.6%). ELISA and SPRCruzi showed almost perfect agreement, mainly between chagasic and non-infected individuals. However, the new immunoassay was better in discriminate Chagas disease from other diseases. CONCLUSION: This work demonstrated the applicability of SPRCruzi as a feasible, real time, label free, sensible and specific methodology for the diagnosis of Chagas disease.


Asunto(s)
Anticuerpos Antiprotozoarios/sangre , Enfermedad de Chagas/diagnóstico , Inmunoensayo/métodos , Resonancia por Plasmón de Superficie/métodos , Tripanocidas/sangre , Anticuerpos Antiprotozoarios/inmunología , Enfermedad de Chagas/sangre , Enfermedad de Chagas/inmunología , Ensayo de Inmunoadsorción Enzimática , Humanos , Tripanocidas/inmunología
5.
Biosens Bioelectron ; 46: 22-9, 2013 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-23500472

RESUMEN

In this work, a surface plasmon resonance (SPR) immunosensor was developed using an 11-mercaptoundecanoic acid (11-MUA) modified gold SPR sensor chip for the detection of anti-Leishmania infantum antibodies. The soluble antigens of L. infantum were securely immobilized on an SPR gold disk by an 11-MUA self-assembled monolayer. Cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and scanning electrochemical microscopy (SECM) techniques were employed in the characterization of the antigen immobilization. After the immunosensor construction, canine serum positive for visceral leishmaniasis was added to its surface and showed significant variation in the SPR angle, indicating excellent sensitivity of the technique for antigen-antibody interaction detection. Moreover, the addition of negative serum was accompanied by a smaller response, demonstrating that the immunosensor shows good specificity against anti-L. infantum antibodies. Therefore, this work demonstrates the successful development of an SPR sensor for anti-L. infantum antibodies detection in short time, showing a great perspective as a sensing system of visceral leishmaniasis in endemic regions.


Asunto(s)
Anticuerpos Antiprotozoarios/sangre , Leishmania infantum/inmunología , Leishmaniasis Visceral/sangre , Leishmaniasis Visceral/veterinaria , Resonancia por Plasmón de Superficie/métodos , Animales , Antígenos de Protozoos/química , Perros , Ácidos Grasos/química , Oro/química , Proteínas Inmovilizadas/química , Inmunoensayo/métodos , Leishmania infantum/aislamiento & purificación , Leishmaniasis Visceral/diagnóstico , Sensibilidad y Especificidad , Compuestos de Sulfhidrilo/química
6.
Mem. Inst. Oswaldo Cruz ; 104(8): 1139-1147, Dec. 2009. ilus, tab
Artículo en Inglés | LILACS | ID: lil-538174

RESUMEN

Twenty-eight Chagas disease patients (CD), 22 with the indeterminate clinical form (IND) and six with the cardiac or digestive form (CARD/DIG), were treated with benznidazole and underwent clinical and laboratorial analysis before (IND and CARD/DIG) and nine years after [patients after treatment (CDt), patients with the indeterminate clinical form at treatment onset (INDt) and with the cardiac or digestive form at treatment onset (CARD/DIGt)] treatment. The data demonstrate that 82.1 percent of CDt patients (23/28) remained clinically stable and 95.4 percent of the INDt (21/22) and 33.3 percent of the CARD/DIGt (2/6) patients showed unaltered physical and laboratorial examinations. The clinical evolution rate was 2 percent/year and was especially low in INDt patients (0.5 percent/year) relative to CARD/DIGt patients (7.4 percent/year). Positive haemoculture in treated patients was observed in 7.1 percent of the cases. None of the INDt (0/21) and 33.3 percent of the CARD/DIGt (2/6) patients displayed positive cultures. The PCR presented a positive rate significantly higher (85.2 percent, 23/27) than haemoculture and two samples from the same patient revealed the same result 57.7 percent of the patients. Conventional serology-ELISA on 16 paired samples remained positive in all individuals. Semi-quantitative ELISA highlighted significant decreases in reactivity, particularly in INDt relative to IND. Non-conventional serology-FC-ALTA-IgG, after treatment, showed positive results in all sera and 22 paired samples examined at seven and nine years after treatment, demonstrated significantly lower reactivity, particularly in INDt patients. This study was retrospective in nature, had a low number of samples and lacked an intrinsic control group, but the data corroborate other results found in the literature. The data also demonstrate that, even though a cure has not been detected in the none-treated patients, the benefits for clinical evolution ...


Asunto(s)
Adolescente , Adulto , Niño , Femenino , Humanos , Masculino , Adulto Joven , Enfermedad de Chagas/tratamiento farmacológico , Nitroimidazoles/uso terapéutico , Tripanocidas/uso terapéutico , Trypanosoma cruzi/inmunología , Anticuerpos Antiprotozoarios/sangre , Brasil , Enfermedad Crónica , Cardiomiopatía Chagásica/tratamiento farmacológico , Cardiomiopatía Chagásica/inmunología , Enfermedad de Chagas/inmunología , Ensayo de Inmunoadsorción Enzimática , Inmunoglobulina G/inmunología , Resultado del Tratamiento , Adulto Joven
7.
Mem Inst Oswaldo Cruz ; 104(8): 1139-47, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20140375

RESUMEN

Twenty-eight Chagas disease patients (CD), 22 with the indeterminate clinical form (IND) and six with the cardiac or digestive form (CARD/DIG), were treated with benznidazole and underwent clinical and laboratorial analysis before (IND and CARD/DIG) and nine years after [patients after treatment (CDt), patients with the indeterminate clinical form at treatment onset (INDt) and with the cardiac or digestive form at treatment onset (CARD/DIGt)] treatment. The data demonstrate that 82.1% of CDt patients (23/28) remained clinically stable and 95.4% of the INDt (21/22) and 33.3% of the CARD/DIGt (2/6) patients showed unaltered physical and laboratorial examinations. The clinical evolution rate was 2%/year and was especially low in INDt patients (0.5%/year) relative to CARD/DIGt patients (7.4%/year). Positive haemoculture in treated patients was observed in 7.1% of the cases. None of the INDt (0/21) and 33.3% of the CARD/DIGt (2/6) patients displayed positive cultures. The PCR presented a positive rate significantly higher (85.2%, 23/27) than haemoculture and two samples from the same patient revealed the same result 57.7% of the patients. Conventional serology-ELISA on 16 paired samples remained positive in all individuals. Semi-quantitative ELISA highlighted significant decreases in reactivity, particularly in INDt relative to IND. Non-conventional serology-FC-ALTA-IgG, after treatment, showed positive results in all sera and 22 paired samples examined at seven and nine years after treatment, demonstrated significantly lower reactivity, particularly in INDt patients. This study was retrospective in nature, had a low number of samples and lacked an intrinsic control group, but the data corroborate other results found in the literature. The data also demonstrate that, even though a cure has not been detected in the none-treated patients, the benefits for clinical evolution were selectively observed in the group of INDt patients and did not occur for CARD/DIGt patients.


Asunto(s)
Enfermedad de Chagas/tratamiento farmacológico , Nitroimidazoles/uso terapéutico , Tripanocidas/uso terapéutico , Trypanosoma cruzi/inmunología , Adolescente , Adulto , Anticuerpos Antiprotozoarios/sangre , Brasil , Cardiomiopatía Chagásica/tratamiento farmacológico , Cardiomiopatía Chagásica/inmunología , Enfermedad de Chagas/inmunología , Niño , Enfermedad Crónica , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Inmunoglobulina G/inmunología , Masculino , Resultado del Tratamiento , Adulto Joven
8.
Mem Inst Oswaldo Cruz ; 103(6): 528-34, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18949320

RESUMEN

The goals of the present study were to evaluate the kinetics of blood parasitism by examination of fresh blood, blood culture (BC) and PCR assays and their correlation with heart parasitism during two years of infection in Beagle dogs inoculated with the Be-78, Y and ABC Trypanosoma cruzi strains. Our results showed that the parasite or its kDNA is easily detected during the acute phase in all infected animals. On the other hand, a reduced number of positive tests were verified during the chronic phase of the infection. The frequency of positive tests was correlated with T. cruzi strain. The percentage of positive BC and blood PCR performed in samples from animals inoculated with Be-78 and ABC strains were similar and significantly larger in relation to animals infected with the Y strain.Comparison of the positivity of PCR tests performed using blood and heart tissue samples obtained two years after infection showed two different patterns associated with the inoculated T. cruzi strain: (1) high PCR positivity for both blood and tissue was observed in animals infected with Be-78 or ABC strains; (2) lower and higher PCR positivity for the blood and tissue, respectively, was detected in animals infected with Y strains. These data suggest that the sensitivity of BC and blood PCR was T. cruzi strain dependent and, in contrast, the heart tissue PCR revealed higher sensitivity regardless of the parasite stock.


Asunto(s)
Cardiomiopatía Chagásica/parasitología , Parasitemia/parasitología , Trypanosoma cruzi/patogenicidad , Enfermedad Aguda , Animales , Cardiomiopatía Chagásica/patología , Enfermedad Crónica , Modelos Animales de Enfermedad , Perros , Femenino , Fibrosis/parasitología , Fibrosis/patología , Inflamación/parasitología , Inflamación/patología , Masculino , Parasitemia/patología , Reacción en Cadena de la Polimerasa , Trypanosoma cruzi/clasificación
9.
Mem. Inst. Oswaldo Cruz ; 103(6): 528-534, Sept. 2008. ilus, graf, tab
Artículo en Inglés | LILACS | ID: lil-495726

RESUMEN

The goals of the present study were to evaluate the kinetics of blood parasitism by examination of fresh blood, blood culture (BC) and PCR assays and their correlation with heart parasitism during two years of infection in Beagle dogs inoculated with the Be-78, Y and ABC Trypanosoma cruzi strains. Our results showed that the parasite or its kDNA is easily detected during the acute phase in all infected animals. On the other hand, a reduced number of positive tests were verified during the chronic phase of the infection. The frequency of positive tests was correlated with T. cruzi strain. The percentage of positive BC and blood PCR performed in samples from animals inoculated with Be-78 and ABC strains were similar and significantly larger in relation to animals infected with the Y strain.Comparison of the positivity of PCR tests performed using blood and heart tissue samples obtained two years after infection showed two different patterns associated with the inoculated T. cruzi strain: (1) high PCR positivity for both blood and tissue was observed in animals infected with Be-78 or ABC strains; (2) lower and higher PCR positivity for the blood and tissue, respectively, was detected in animals infected with Y strains. These data suggest that the sensitivity of BC and blood PCR was T. cruzi strain dependent and, in contrast, the heart tissue PCR revealed higher sensitivity regardless of the parasite stock.


Asunto(s)
Animales , Perros , Femenino , Masculino , Cardiomiopatía Chagásica/parasitología , Parasitemia/parasitología , Trypanosoma cruzi/patogenicidad , Enfermedad Aguda , Enfermedad Crónica , Cardiomiopatía Chagásica/patología , Modelos Animales de Enfermedad , Fibrosis/parasitología , Fibrosis/patología , Inflamación/parasitología , Inflamación/patología , Reacción en Cadena de la Polimerasa , Parasitemia/patología , Trypanosoma cruzi/clasificación
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