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1.
J. venom. anim. toxins incl. trop. dis ; 30: e20230043, 2024. graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1534803

RESUMO

Background: The bioactive peptides derived from snake venoms of the Viperidae family species have been promising as therapeutic candidates for neuroprotection due to their ability to prevent neuronal cell loss, injury, and death. Therefore, this study aimed to evaluate the cytoprotective effects of a synthetic proline-rich oligopeptide 7a (PRO-7a; <EDGPIPP) from Bothrops jararaca snake, on oxidative stress-induced toxicity in neuronal PC12 cells and astrocyte-like C6 cells. Methods: Both cells were pre-treated for four hours with different concentrations of PRO-7a, submitted to H2O2-induced damage for 20 h, and then the oxidative stress markers were analyzed. Also, two independent neuroprotective mechanisms were investigated: a) L-arginine metabolite generation via argininosuccinate synthetase (AsS) activity regulation to produce agmatine or polyamines with neuroprotective properties; b) M1 mAChR receptor subtype activation pathway to reduce oxidative stress and neuron injury. Results: PRO-7a was not cytoprotective in C6 cells, but potentiated the H2O2-induced damage to cell integrity at a concentration lower than 0.38 μM. However, PRO-7a at 1.56 µM, on the other hand, modified H2O2-induced toxicity in PC12 cells by restoring cell integrity, mitochondrial metabolism, ROS generation, and arginase indirect activity. The α-Methyl-DL-aspartic acid (MDLA) and L-NΩ-Nitroarginine methyl ester (L-Name), specific inhibitors of AsS and nitric oxide synthase (NOS), which catalyzes the synthesis of polyamines and NO from L-arginine, did not suppress PRO-7a-mediated cytoprotection against oxidative stress. It suggested that its mechanism is independent of the production of L-arginine metabolites with neuroprotective properties by increased AsS activity. On the other hand, the neuroprotective effect of PRO-7a was blocked in the presence of dicyclomine hydrochloride (DCH), an M1 mAChR antagonist. Conclusions: For the first time, this work provides evidence that PRO-7a-induced neuroprotection seems to be mediated through M1 mAChR activation in PC12 cells, which reduces oxidative stress independently of AsS activity and L-arginine bioavailability.(AU)


Assuntos
Oligopeptídeos/efeitos adversos , Receptores Muscarínicos/química , Venenos de Crotalídeos/síntese química , Prolina , Estresse Oxidativo
2.
Braz. j. oral sci ; 22: e237270, Jan.-Dec. 2023. ilus
Artigo em Inglês | LILACS, BBO - Odontologia | ID: biblio-1413378

RESUMO

Opiorphin is a pentapeptide, which could be isolated from human fluids and has a decreasing effect on pain. Aim: Since lichen planus is a chronic mucocutaneous disease, which causes pain or burning feeling in the oral mucosa, this study aimed to compare salivary opiorphin levels of oral lichen planus (OLP) patients with healthy subjects. Methods: This case-control study, was performed on 24 patients with OLP lesions and 21 healthy subjects. After collecting unstimulated saliva, opiorphin levels were compared between two groups through statistical analyses. Results: There was not any significant difference between OLP patients and healthy subjects according to salivary opiorphin concentration (p=0.378). Also, in the OLP group, opiorphin concentration was not significantly different between males and females (p=0.601). Analytical analysis could not show any remarkable difference between various severity of OLP lesions regarding to salivary opiorphin levels (p=0.653). Conclusion: In this study, salivary opiorphin levels was not significantly different between patients with OLP and healthy subjects; however, more studies are suggested for better assessment of salivary opiorphin levels in various types of OLP lesions and its correlation with pain severity


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Oligopeptídeos , Dor , Saliva , Líquen Plano Bucal
3.
Int. j. morphol ; 40(6): 1587-1593, dic. 2022. ilus, tab, graf
Artigo em Inglês | LILACS | ID: biblio-1421824

RESUMO

SUMMARY: This study is to investigate the role and mechanism of RGD peptide in laryngeal cancer stem cells (CSCs). Laryngeal cancer CD133+Hep-2 CSCs were sorted by flow cytometry. RGD peptide was co-cultured with sorted laryngeal CSCs. Cell proliferation was detected with CCK-8 assay. The mRNA levels of VEGF/VEGFR2/STAT 3/HIF-1α were detected with RT-PCR. The proteins of VEGF/ VEGFR2/STAT 3/HIF-1α were detected with Western blot. The sorted CSCs were inoculated into nude mice. Tumor volume was measured. Integrin αvβ3 expression in tumor tissues was analyzed with immunohistochemistry. The results showed that the ratio of CD133+ CSCs to the total number of cells was 1.34±0.87 %, while CD133-non-tumor stem cells accounted for 95.0±5.76 %. The sorted cancer stem cells grew well. The RGD peptide significantly inhibited the proliferation of CD133+Hep-2 laryngeal CSCs in a dose-dependent manner. The RGD peptide significantly inhibited the mRNA of VEGFR2, STAT3 and HIF-1α in laryngeal CSCs in a concentration-dependent manner. Consistently, the RGD peptide significantly inhibited the protein expression of VEGFR2, STAT3 and HIF-1α in laryngeal CSCs in a dose-dependent manner. At the same time, in vivo tumor experiments showed that the RGD peptide significantly inhibited tumor volume but not the body weight. Furthermore, RGD peptide significantly inhibited the expression of tumor angiogenesis-related protein integrin αvβ3. Our findings demonstrate that RGD peptide inhibits tumor cell proliferation and tumor growth. The underlying mechanism may that RGD inhibits tumor angiogenesis-related signaling pathways, thus affecting the tumor angiogenesis, and decreasing the progression of human laryngeal CSCs.


Este estudio se realizó para investigar el papel y el mecanismo del péptido RGD en las células madre del cáncer de laringe (CSC). Las CSC CD133+Hep-2 de cáncer de laringe se clasificaron mediante citometría de flujo. El péptido RGD se cocultivó con CSC laríngeas clasificadas. La proliferación celular se detectó con el ensayo CCK-8. Los niveles de ARNm de VEGF/VEGFR2/ STAT 3/HIF-1α se detectaron con RT-PCR. Las proteínas de VEGF/ VEGFR2/STAT 3/HIF-1α se detectaron con Western blot. Las CSC clasificadas se inocularon en ratones nudos. Se midió el volumen del tumor. La expresión de integrina αvβ3 en tejidos tumorales se analizó con inmunohistoquímica. Los resultados mostraron que la proporción de CSC CD133+ con respecto al número total de células fue de 1,34 ± 0,87 %, mientras que las células madre no tumorales CD133 representaron el 95,0 ± 5,76 %. Las células madre cancerosas clasificadas crecieron bien. El péptido RGD inhibió significativamente la proliferación de CSC laríngeas CD133+Hep-2 de una manera dependiente de la dosis. El péptido RGD inhibió significativamente el ARNm de VEGFR2, STAT3 y HIF-1α en CSC laríngeas de manera dependiente de la concentración. De manera consistente, el péptido RGD inhibió significativamente la expresión proteica de VEGFR2, STAT3 y HIF-1α en CSC laríngeas, de manera dependiente de la dosis. Al mismo tiempo, los experimentos con tumores in vivo mostraron que el péptido RGD inhibía significativamente el volumen del tumor pero no el peso corporal. Además, el péptido RGD inhibió significativamente la expresión de la proteína integrina αvβ3 relacionada con la angiogénesis tumoral. Nuestros hallazgos demuestran que el péptido RGD inhibe la proliferación de células tumorales y el crecimiento tumoral. El mecanismo subyacente puede ser que RGD inhiba las vías de señalización relacionadas con la angiogénesis tumoral, afectando así la angiogénesis tumoral y disminuyendo la progresión de las CSC laríngeas humanas.


Assuntos
Animais , Camundongos , Oligopeptídeos/metabolismo , Células-Tronco Neoplásicas , Neoplasias Laríngeas , RNA Mensageiro/antagonistas & inibidores , Imuno-Histoquímica , Western Blotting , Primers do DNA , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Integrina alfaVbeta3/antagonistas & inibidores , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Fator A de Crescimento do Endotélio Vascular/genética , Proliferação de Células , Citometria de Fluxo , Neovascularização Patológica
5.
Cad. Saúde Pública (Online) ; 36(2): e00036619, 2020. graf
Artigo em Inglês | LILACS | ID: biblio-1055632

RESUMO

Abstract: Cost-effectiveness analysis is essential in health decision making. Several countries use it as synthesis of evidence to incorporate health technologies. The protease inhibitors (PI) boceprevir (BOC) and telaprevir (TVR) are indicated for chronic hepatitis C treatment and were incorporated in guidelines worldwide. Pre-marketing clinical trials showed higher sustained virological response rates in relation to previous therapies, but the incorporation of PIs generated a significant financial impact. The aim of this study was to discuss the relevance of cost-effectiveness analysis through a study that involved the inclusion of PIs in a clinical protocol. The analysis was part of a real-life study that included patients infected with hepatitis C virus genotype 1 treated in a tertiary university hospital in Brazil. Triple therapies (TT) with ribavirin (RBV), peginterferon α-2a (Peg-INF α-2a) and BOC or TVR were compared to dual therapy with RBV and Peg-INF α-2a. Sensitivity analysis of the cost-effectiveness ratio indicated an 88.2% chance of TTs presenting a higher cost per cure. The incremental cost-effectiveness ratios (ICER) exceeded the Brazilian gross domestic product (GDP) per capita by three times in all proposed scenarios. The sensitivity of ICER showed an 88.4% chance of TT not being cost-effective. The impact of PI incorporation was negative and the conduct about this could have been different if a previous cost-effectiveness analysis had been conducted.


Resumo: A análise de custo-efetividade tem sido essencial para a tomada de decisões em saúde. Diversos países utilizam esse tipo de análise como síntese das evidências para incorporar as tecnologias em saúde. Os inibidores de protease (IPs) boceprevir (BOC) e telaprevir (TVR) são indicados para o tratamento da hepatite C crônica e foram incorporados nas diretrizes internacionais. Os ensaios clínicos pré-marketing demonstraram taxas mais altas de resposta virológica sustentada em relação às terapias anteriores, mas a incorporação dos IPs gerou um impacto financeiro significativo. O estudo teve como objetivo discutir a relevância da análise de custo-efetividade, através de um estudo que envolveu a inclusão de IPs em um protocolo clínico. A análise fez parte de um estudo de vida real que incluiu pacientes com infecção pelo vírus da hepatite C, genótipo 1, tratados em um hospital universitário terciário no Brasil. As terapias triplas (TTs) com ribavirina (RBV), peg-interferon α-2a (Peg-INF α-2a) e BOC ou TVR foram comparadas às terapias duplas com RBV e Peg-INF α-2a. A análise de sensibilidade da custo-efetividade indicou odds de 88,2% de TTs apresentarem custo mais elevado por paciente curado. Em todos os cenários propostos, as razões de custo-efetividade incremental (ICERs) superaram em três vezes o produto interno bruto (PIB) per capita brasileiro. A sensibilidade da ICER mostrou probabilidade de 88,4% das TTs não serem custo-efetivas. O impacto da incorporação dos IPs foi negativo, e a conduta teria sido diferente se tivesse sido realizada uma análise prévia de custo-efetividade.


Resumen: El análisis de coste-efectividad ha sido esencial para la toma de decisiones en salud. Diversos países utilizan este tipo de análisis como síntesis de evidencias para incorporar tecnologías en salud. Los inhibidores de proteasa (IPs) boceprevir (BOC) y telaprevir (TVR) se indican para el tratamiento de la hepatitis C crónica y fueron incorporados en directrices internacionales. Los ensayos clínicos pre-marketing demostraron tasas más altas de respuesta virológica sostenida, respecto a las terapias anteriores, pero la incorporación de los IPs generó un impacto financiero significativo. El objetivo del estudio fue discutir la relevancia del análisis de coste-efectividad, a través de un estudio que implicó la inclusión de IPs en un protocolo clínico. El análisis formó parte de un estudio de vida real que incluyó a pacientes con infección por el virus de la hepatitis C, genotipo 1, tratados en un hospital universitario terciario en Brasil. Las terapias triples (TTs) con ribavirina (RBV), peg-interferon α-2a (Peg-INF α-2a) y BOC o TVR se compararon con las terapias dobles con RBV y Peg-INF α-2a. El análisis de sensibilidad del coste-efectividad indicó odds de 88,2% de que las TTs presentaran un coste más elevado por paciente curado. En todos los escenarios propuestos, las razones de coste-efectividad incremental (ICERs) superaron tres veces el producto interno bruto (PIB) per cápita brasileño. La sensibilidad de la ICER mostró una probabilidad de que un 88,4% de las TTs no eran costo-efectivas. El impacto de la incorporación de los IPs fue negativo, y el resultado habría sido diferente si se hubiese realizado un análisis previo de coste-efectividad.


Assuntos
Humanos , Antivirais/uso terapêutico , Análise Custo-Benefício , Hepatite C Crônica/tratamento farmacológico , Oligopeptídeos , Antivirais/economia , Polietilenoglicóis , Ribavirina , Proteínas Recombinantes , Brasil , Prolina/análogos & derivados , Interferon-alfa , Hepacivirus , Anos de Vida Ajustados por Qualidade de Vida , Hepatite C Crônica/economia , Quimioterapia Combinada , Interferon alfa-2 , Genótipo
6.
Int. braz. j. urol ; 45(3): 459-467, May-June 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1012312

RESUMO

ABSTRACT Purpose: 68Ga-PSMA PET/CT imaging is a promising modality for the staging of recurrent prostate cancer (PCa). Current evidence suggests limited diagnostic value of the 68Ga-PSMA PET/CT in PSA-levels ≤0.3ng/mL. Experimental data have demonstrated an increase in PSMA-expression in PCa metastases by androgen deprivation in vitro. The aim of the current study was to investigate a possible enhancing effect of PSMA with low-dose androgen deprivation in patients with BCR and low PSA-levels. Materials and Methods: Five patients with PCa and BCR, following radical prostatectomy, underwent 68Ga-PSMA PET/CT. A consecutive 68Ga-PSMA PET/CT was performed 6 to 11 days after injection of 80mg of Degarelix (Firmagon®). We recorded PSA and testosterone serum-levels and changes of PSMA-uptake in 68Ga-PSMA PET/CT images. Results: Median PSA prior 68Ga-PSMA PET/CT was 0.27ng/mL. All patients had a decrease in testosterone serum levels from median 2.95μg/l to 0.16μg/l following Degarelix injection. We observed an increase in the standardized uptake value (SUV) in PSMA-positive lymphogenous and osseous lesions in two patients following androgen deprivation. In another two patients, no PSMA positive signals were detected in either the first or the second scan. Conclusion: Our preliminary results of this feasibility assessment indicate a possible enhancing effect of PSMA-imaging induced by low-dose ADT. Despite several limitations and the small number of patients, this could be a new approach to improve staging by 68Ga-PSMA PET/CT in PCa patients with BCR after primary therapy. Further prospective studies with larger number of patients are needed to validate our findings.


Assuntos
Humanos , Masculino , Idoso , Compostos Organometálicos , Neoplasias da Próstata/patologia , Glicoproteínas de Membrana , Compostos Radiofarmacêuticos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Antagonistas de Androgênios/uso terapêutico , Metástase Neoplásica/diagnóstico por imagem , Oligopeptídeos/uso terapêutico , Valores de Referência , Fatores de Tempo , Reprodutibilidade dos Testes , Antígeno Prostático Específico/sangue , Gradação de Tumores , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia
7.
Braz. j. med. biol. res ; 52(11): e8441, 2019. graf
Artigo em Inglês | LILACS | ID: biblio-1039261

RESUMO

The heptapeptide Bj-PRO-7a, isolated and identified from Bothrops jararaca (Bj) venom, produces antihypertensive and other cardiovascular effects that are independent on angiotensin converting enzyme inhibition, possibly relying on cholinergic muscarinic receptors subtype 1 (M1R). However, whether Bj-PRO-7a acts upon the central nervous system and modifies behavior is yet to be determined. Therefore, the aims of this study were: i) to assess the effects of acute administration of Bj-PRO-7a upon behavior; ii) to reveal mechanisms involved in the effects of Bj-PRO-7a upon locomotion/exploration, anxiety, and depression-like behaviors. For this purpose, adult male Wistar (WT, wild type) and spontaneous hypertensive rats (SHR) received intraperitoneal injections of vehicle (0.9% NaCl), diazepam (2 mg/kg), imipramine (15 mg/kg), Bj-PRO-7a (71, 213 or 426 nmol/kg), pirenzepine (852 nmol/kg), α-methyl-DL-tyrosine (200 mg/kg), or chlorpromazine (2 mg/kg), and underwent elevated plus maze, open field, and forced swimming tests. The heptapeptide promoted anxiolytic and antidepressant-like effects and increased locomotion/exploration. These effects of Bj-PRO-7a seem to be dependent on M1R activation and dopaminergic receptors and rely on catecholaminergic pathways.


Assuntos
Animais , Masculino , Ratos , Oligopeptídeos/farmacologia , Ansiedade , Comportamento Animal/efeitos dos fármacos , Venenos de Crotalídeos/química , Depressão , Comportamento Exploratório/efeitos dos fármacos , Oligopeptídeos/isolamento & purificação , Comportamento Animal/fisiologia , Prolina/isolamento & purificação , Prolina/farmacologia , Ratos Wistar
8.
Braz. j. med. biol. res ; 52(1): e7844, 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-974274

RESUMO

Necroptosis is a regulated cell death mechanism. However, it is unknown whether necroptosis is involved in the death of tumor necrosis factor-α (TNF-α)-treated osteoblasts. Therefore, we conducted the study with TNF-α, Nec-1 (a specific inhibitor of necroptosis), and Z-IETD-FMK (a specific inhibitor of apoptosis) to determine whether necroptosis plays a role in the death of TNF-α-treated osteoblast cell line MC3T3-E1. Cell viability, cell death, and lactate dehydrogenase (LDH) release were assayed to evaluate cytotoxicity. Specific marker proteins receptor interacting protein kinase (RIPK3) and phosphorylated mixed lineage kinase domain-like protein (p-MLKL) for necroptosis, and cleaved caspase 3 for apoptosis were detected by western blot, and mRNA was measured by quantitative real-time polymerase chain reaction (qRT-PCR). We found that TNF-α inhibited cell proliferation in a dose- and time-dependent manner. Nec-1 plus Z-IETD-FMK restored cell viability and significantly decreased LDH release. In addition, TNF-α alone increased the cell population of AV+PI−, while Z-IETD-FMK caused a shift in the cell population from AV+PI− to AV+PI+. Furthermore, TNF-α significantly increased protein cleaved caspase 3. TNF-α plus Z-IETD-FMK significantly increased the proteins RIPK3 and MLKL phosphorylation in MC3T3-E1 cells, while the changes in mRNA levels of RIPK3, MLKL, and caspase 3 were not consistent with the changes in the corresponding protein expression levels. In conclusion, TNF-α induced preferentially apoptosis in osteoblast cell line and necroptosis played a decisive role when TNF-α-induced death was inhibited by the inhibitor of apoptosis. Combined treatment with Nec-1 and Z-IETD-FMK protected mouse osteoblasts from death induced by TNF-α.


Assuntos
Animais , Coelhos , Osteoblastos/patologia , Fator de Necrose Tumoral alfa/farmacologia , Caspase 8/efeitos dos fármacos , Inibidores de Caspase/farmacologia , Necrose/patologia , Oligopeptídeos/farmacologia , Osteoblastos/efeitos dos fármacos , Fosforilação , Sobrevivência Celular/efeitos dos fármacos , Imidazóis/farmacologia , Indóis/farmacologia , L-Lactato Desidrogenase/farmacologia
9.
Rev. Soc. Bras. Med. Trop ; 51(6): 731-736, Nov.-Dec. 2018. tab
Artigo em Inglês | LILACS | ID: biblio-977101

RESUMO

Abstract INTRODUCTION: Chronic hepatitis C is a leading cause of liver disease. Infection triggers an immediate immune response in the host that is mediated by humoral/cellular mechanisms. T cells respond to infection via secretion of cytokines, which inhibit or stimulate one another, leading to cytokine imbalance and ultimately affecting treatment. Studies using interferon (IFN) and ribavirin (RBV) showed that TCD8+ cells and cytokine levels are associated with sustainable virological response (SVR). However, studies that investigated the effects of triple therapy (TT) are limited. METHODS: The study included hepatitis C virus (HCV)+ RNA, naives, genotype 1, ≥18 years, and advanced fibrosis (F≥3) patients. Samples were collected at baseline and after 12 weeks (W12) of TT. Six cytokines were analyzed by flow cytometry. RESULTS: Of 31 patients, four were excluded (two deaths, one interrupted TT, and one F2 patient). Of the 27 remaining patients, 21 (78%) were cirrhotic. SVR was achieved in 63% of the patients. The patients had a mean age of 55.11 ± 10.03 years. Analyses at baseline showed that the chemokine CCL5/Regulated on Activation, Normal T Cell Expressed and Secreted (RANTES) (p=0.04) and interleukin (IL)-6 (p=0.02), which was associated with SVR. RANTES (p=0.04) and IL-8 (p=0.01) levels were associated with SVR at W12. CONCLUSIONS Similar to patterns observed during double therapy, IL-6, IL-8, and RANTES levels were associated with SVR in TT, indicating the potential role of interferon in immune response to hepatitis C virus.


Assuntos
Humanos , Masculino , Feminino , Oligopeptídeos/administração & dosagem , Antivirais/administração & dosagem , Prolina/análogos & derivados , Citocinas/sangue , Hepatite C Crônica/tratamento farmacológico , Prolina/administração & dosagem , Estudos Prospectivos , Resultado do Tratamento , Carga Viral , Hepatite C Crônica/sangue , Quimioterapia Combinada , Citometria de Fluxo , Genótipo , Pessoa de Meia-Idade
10.
Int. braz. j. urol ; 44(5): 892-899, Sept.-Oct. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-975631

RESUMO

ABSTRACT Purpose: The purpose of our study was to evaluate the clinical impact of 68Ga-PSMA PET / CT in the setting of biochemical recurrence of prostate cancer. Materials and Methods: We retrospectively evaluated 125 prostate cancer patients submitted to the 68Ga-PSMA PET / CT due to biochemical recurrence. The parameters age, Gleason score, PSA levels, and the highest SUVmax were correlated to potential treatment changes. The highest SUVmax values were correlated with age and Gleason score. The median follow-up time was 24 months. Results: 68Ga-PSMA PET / CT led to a treatment change in 66 / 104 (63.4%) patients (twenty-one patients were lost to follow-up). There was a significant change of treatment plan in patients with a higher Gleason score (P = 0.0233), higher SUVmax (p = 0.0306) and higher PSA levels (P < 0.0001; median PSA = 2.55 ng / mL). Conclusion: 68Ga-PSMA PET / CT in prostate cancer patients with biochemical recurrence has a high impact in patient management.


Assuntos
Humanos , Masculino , Adulto , Idoso , Idoso de 80 Anos ou mais , Oligopeptídeos , Neoplasias da Próstata/sangue , Neoplasias da Próstata/diagnóstico por imagem , Ácido Edético/análogos & derivados , Antígeno Prostático Específico/sangue , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Recidiva Local de Neoplasia/diagnóstico por imagem , Neoplasias da Próstata/terapia , Estudos Retrospectivos , Seguimentos , Sensibilidade e Especificidade , Gradação de Tumores , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/terapia
11.
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
12.
Rev. Soc. Bras. Med. Trop ; 51(2): 146-154, Mar.-Apr. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-897067

RESUMO

Abstract INTRODUCTION: Licensed for chronic hepatitis C treatment in 2011, the protease inhibitors (PIs) telaprevir (TVR) and boceprevir (BOC), which have high sustained viral responses (SVR), ushered a new era characterized by the development of direct-action drugs against the hepatitis C virus (HCV). The aim of this study was to analyze the effectiveness and safety of BOC and TVR administered with pegylated interferon and ribavirin and to share the experience of a Brazilian reference center. METHODS: A retrospective descriptive study was conducted in patients with HCV genotype 1 infection who started treatment between July 2013 and December 2015. Data were collected using a computerized system. RESULTS: A total of 115 subjects were included, of which 58 (50.4 %) had liver cirrhosis and 103 (89.6 %) used TVR. The overall SVR rate was 61.7 % (62.1 % for TVR and 58.3 % for BOC). The presence of cirrhosis was associated with a lower SVR rate, whereas patients who relapsed after prior therapy had a greater chance of showing SVR than did non-responders. The incidence of adverse drug reactions (ADRs) was high. Almost all patients (~100 %) presented with hematologic events. Furthermore, treatment had to be discontinued in 15 subjects (13 %) due to severe ADRs. CONCLUSIONS: In conclusion, the SVR rates in our study were lower than those reported in pre-marketing studies but were comparable to real-life data. ADRs, particularly hematological ADRs, were more common compared to those in previous studies and resulted in a high rate of treatment discontinuity.


Assuntos
Humanos , Masculino , Feminino , Adulto , Idoso , Antivirais/administração & dosagem , Inibidores de Proteases/administração & dosagem , Hepacivirus/genética , Hepatite C Crônica/tratamento farmacológico , Oligopeptídeos/administração & dosagem , Oligopeptídeos/efeitos adversos , Antivirais/efeitos adversos , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/efeitos adversos , Inibidores de Proteases/efeitos adversos , Ribavirina/administração & dosagem , Ribavirina/efeitos adversos , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/efeitos adversos , Prolina/administração & dosagem , Prolina/análogos & derivados , Prolina/efeitos adversos , Estudos Retrospectivos , Resultado do Tratamento , Interferon-alfa/administração & dosagem , Interferon-alfa/efeitos adversos , Hepacivirus/efeitos dos fármacos , Hepatite C Crônica/genética , Hepatite C Crônica/virologia , Quimioterapia Combinada , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Interferon alfa-2 , Genótipo , Pessoa de Meia-Idade
13.
An. acad. bras. ciênc ; 90(1): 73-84, Mar. 2018. tab
Artigo em Inglês | LILACS | ID: biblio-886885

RESUMO

ABSTRACT The adhesion ability of bacteria to abiotic surfaces has important implications in food industries, because these organisms can survive for long periods through the biofilm formation. They can be transferred from one place to another in the industry causing contamination of the food processing environment. In this study, the antibacterial and antibiofilm activities of the antimicrobial peptide P34, characterized as a bacteriocin-like substance (BLS P34) were tested against planktonic and sessile cells of Staphylococcus aureus and Enterococcus faecalis isolated from foods. The BLS P34 showed inhibitory effect against all planktonic cells of E. faecalis. The inhibition of biofilm formation and the eradication of pre-formed biofilm were evaluated with the crystal violet assay and with the reduction of 3-bromide [4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium. The BLS P34 promoted a reduction of percentage of adhered microbial cells on the surface, not being able to perform the complete elimination of biofilm formation. The metabolic activity of S. aureus biofilms decreased considerably between 41-95%. However, E. faecalis cells showed up metabolically stimulated. The BLS P34 has the potential antibiofilm for the species S. aureus. Studies suggest more detailed approaches to a better understanding of the interactions between the antimicrobial and bacterial cells within the biofilm structure.


Assuntos
Animais , Oligopeptídeos/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Bacteriocinas/farmacologia , Enterococcus faecalis/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Antibacterianos/farmacologia , Bacillus/isolamento & purificação , Bacillus/metabolismo , Bacteriocinas/isolamento & purificação , Aderência Bacteriana/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Análise de Variância
14.
Rev. Soc. Bras. Med. Trop ; 51(1): 14-20, Jan.-Feb. 2018. tab
Artigo em Inglês | LILACS | ID: biblio-897052

RESUMO

Abstract INTRODUCTION: In 2013, combination therapy using peginterferon, ribavirin, and boceprevir or telaprevir was introduced to treat hepatitis C virus genotype 1 infection in Brazil. The effectiveness of this therapy in four Brazilian regions was evaluated. METHODS: Clinical and virological data were obtained from patients of public health institutions in five cities, including sustained virological response (SVR) and side effects. Patients with advanced fibrosis (F3/4), moderate fibrosis (F2) for > 3 years, or extra-hepatic manifestations were treated according to Ministry of Health protocol. Treatment effectiveness was verified by using bivariate and multivariate analysis; p-values of < 0.05 were considered significant. RESULTS: Of 275 patients (64.7% men; average age, 57 years old), most (61.8%) were treatment-experienced; 53.9% had subgenotype 1a infection, 85.1% had advanced fibrosis, and 85.5% were treated with telaprevir. SVR was observed in 54.2%. Rapid virological response (RVR) was observed in 54.6% of patients (data available for 251 patients). Overall, 87.5% reported side effects and 42.5% did not complete treatment. Skin rash, severe infection, and death occurred in 17.8%, 2.5%, and death in 1.4% of cases, respectively. SVR was associated with treatment completion, RVR, and anemia. CONCLUSIONS: The effectiveness of hepatitis C virus triple therapy was lower than that reported in phase III clinical trials, possibly owing to the prioritized treatment of patients with advanced liver fibrosis. The high frequency of side effects and treatment interruptions observed supported the decision of the Brazilian authorities to suspend its use when safer and more effective drugs became available in 2015.


Assuntos
Humanos , Masculino , Feminino , Adulto , Idoso , Inibidores de Proteases/administração & dosagem , Hepacivirus/genética , Hepatite C Crônica/tratamento farmacológico , Oligopeptídeos/administração & dosagem , Ribavirina/administração & dosagem , Prolina/administração & dosagem , Prolina/análogos & derivados , Protocolos Clínicos , Interferons/administração & dosagem , Resultado do Tratamento , Hepatite C Crônica/virologia , Quimioterapia Combinada , Resposta Viral Sustentada , Genótipo , Pessoa de Meia-Idade
15.
Clinics ; 72(6): 378-385, June 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-840088

RESUMO

OBJECTIVE: To evaluate the effectiveness and safety of first-generation protease inhibitors for the treatment of genotype 1 hepatitis C virus-infected patients at Brazilian reference centers. METHODS: This multicenter cross-sectional study included hepatitis C virus genotype 1 monoinfected patients treated with Peg-interferon, ribavirin, and either boceprevir (n=158) or telaprevir (n=557) between July 2013 and April 2014 at 15 reference centers in Brazil. Demographic, clinical, virological, and adverse events data were collected during treatment and follow-up. RESULTS: Of the 715 patients, 59% had cirrhosis and 67.1% were treatment-experienced. Based on intention-to-treat analysis, the overall sustained viral response was 56.6%, with similar effectiveness in both groups (51.9% for boceprevir and 58% for telaprevir, p=0.190). Serious adverse events occurred in 44.2% of patients, and six deaths (0.8%) were recorded. Cirrhotic patients had lower sustained viral response rates than non-cirrhotic patients (46.9% vs. 70.6%, p<0.001) and a higher incidence of serious adverse events (50.7% vs. 34.8%, p<0.001). Multivariate analysis revealed that sustained viral response was associated with the absence of cirrhosis, viral recurrence after previous treatment, pretreatment platelet count greater than 100,000/mm3, and achievement of a rapid viral response. Female gender, age>65 years, diagnosis of cirrhosis, and abnormal hemoglobin levels/platelet counts prior to treatment were associated with serious adverse events. CONCLUSION: Although serious adverse events rates were higher in this infected population, sustained viral response rates were similar to those reported for other patient cohorts.


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Antivirais/administração & dosagem , Hepacivirus/genética , Hepatite C Crônica/tratamento farmacológico , Inibidores de Proteases/administração & dosagem , Brasil , Estudos Transversais , Genótipo , Hepatite C Crônica/virologia , Interferon-alfa/administração & dosagem , Oligopeptídeos/administração & dosagem , Polietilenoglicóis/administração & dosagem , Prolina/administração & dosagem , Prolina/análogos & derivados , Proteínas Recombinantes/administração & dosagem , RNA Viral/genética , Resultado do Tratamento
16.
J. venom. anim. toxins incl. trop. dis ; 23: 33, 2017. graf, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-954809

RESUMO

Background: Venoms represent a still underexplored reservoir of bioactive components that might mitigate or cure diseases in conditions in which conventional therapy is ineffective. The bradykinin-potentiating peptides (BPPs) comprise a class of angiotensin-I converting enzyme (ACE) inhibitors. The BPPs usually consist of oligopeptides with 5 to 13 residues with a high number of proline residues and the tripeptide Ile-Pro-Pro (IPP-tripeptide) in the C-terminus region and have a conserved N-terminal pyroglutamate residue. As a whole, the action of the BPPs on prey and snakebite victims results in the decrease of the blood pressure. The aim of this work was to isolate and characterize novel BPPs from the venom of Bitis gabonica rhinoceros. Methods: The crude venom of B. g. rhinoceros was fractionated by size exclusion chromatography and the peptide fraction (<7 kDa) was separated by reverse phase chromatography (RP-HPLC) and analyzed by ESI-IT-TOF-MS/MS. One new BPP was identified, synthetized and assayed for ACE inhibition and, in vivo, for edema potentiation. Results: Typical BPP signatures were identified in three RP-HPLC fractions. CID fragmentation presented the usual y-ion of the terminal P-P fragment as a predominant signal at m/z 213.1. De novo peptide sequencing identified one Bothrops-like BPP and one new BPP sequence. The new BPP was synthesized and showed poor inhibition over ACE, but displayed significant bradykinin-induced edema potentiation. Conclusions: So far, few BPPs are described in Viperinae, and based on the sequenced peptides, two non-canonical sequences were detected. The possible clinical role of this new peptides remains unclear.(AU)


Assuntos
Animais , Oligopeptídeos , Peptídeos/isolamento & purificação , Bioquímica/classificação , Bradicinina , Viperidae , Bothrops
17.
Braz. j. med. biol. res ; 49(3): e5043, Mar. 2016. graf
Artigo em Inglês | LILACS | ID: lil-771931

RESUMO

Ovarian cancer is one of the most common causes of death from gynecologic tumors and is an important public health issue. Ghrelin is a recently discovered bioactive peptide that acts as a natural endogenous ligand of the growth hormone secretagogue receptor (GHSR). Several studies have identified the protective effects of ghrelin on the mammalian reproductive system. However, little research has been done on the effects of ghrelin on ovarian cancer cells, and the underlying mechanisms of these effects. We sought to understand the potential involvement of mitogen-activated protein kinases (MAPKs) in ghrelin-mediated inhibition of growth of the ovarian line HO-8910. We applied different concentrations of ghrelin and an inhibitor of the ghrelin receptor (D-Lys3-GHRP-6) to HO-8910 cells and observed the growth rate of cells and changes in phosphorylation of the MAPKs ERK1/2, JNK and p38. We discovered that ghrelin-induced apoptosis of HO-8910 cells was though phosphorylated ERK1/2, and that this phosphorylation (as well as p90rsk phosphorylation) was mediated by the GHSR. The ERK1/2 pathway is known to play an essential part in the ghrelin-mediated apoptosis of HO-8910 cells. Hence, our study suggests that ghrelin inhibits the growth of HO-8910 cells primarily through the GHSR/ERK pathway.


Assuntos
Humanos , Feminino , Pessoa de Meia-Idade , Regulação Neoplásica da Expressão Gênica/genética , Grelina/farmacologia , Sistema de Sinalização das MAP Quinases/fisiologia , Neoplasias Ovarianas/genética , Apoptose/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Oligopeptídeos/metabolismo , Neoplasias Ovarianas/metabolismo , Fosforilação/efeitos dos fármacos , Receptores de Grelina/antagonistas & inibidores , Receptores de Grelina/metabolismo , Células Tumorais Cultivadas
18.
J. venom. anim. toxins incl. trop. dis ; 22: [1-15], 2016. ilus, tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1484662

RESUMO

During evolution, nature has embraced different strategies for species to survive. One strategy, applied by predators as diverse as snakes, scorpions, sea anemones and cone snails, is using venom to immobilize or kill a prey. This venom offers a unique and extensive source of chemical diversity as it is driven by the evolutionary pressure to improve prey capture and/or to protect their species. Cone snail venom is an example of the remarkable diversity in pharmacologically active small peptides that venoms can consist of. These venom peptides, called conopeptides, are classified into two main groups based on the number of cysteine residues, namely disulfide-rich and disulfide-poor conopeptides. Since disulfide-poor conotoxins are minor components of this venom cocktail, the number of identified peptides and the characterization of these peptides is far outclassed by its cysteine-rich equivalents. This review provides an overview of 12 families of disulfide-poor peptides identified to date as well as the state of affairs.


Assuntos
Animais , Dissulfetos/análise , Dissulfetos/classificação , Oligopeptídeos/análise , Oligopeptídeos/classificação , Oligopeptídeos/síntese química , Farmacologia/tendências
19.
Braz. j. med. biol. res ; 49(7): e5300, 2016. tab, graf
Artigo em Inglês | LILACS | ID: lil-785056

RESUMO

The aim of this study was to determine risk factors for adverse events (AE)-related treatment discontinuation and severe anemia among patients with chronic hepatitis C virus (HCV) genotype 1 infection, treated with first-generation protease inhibitor (PI)-based therapy. We included all patients who initiated treatment with PI-based therapy at a Brazilian university hospital between November 2013 and December 2014. We prospectively collected data from medical records using standardized questionnaires and used Epi Info 6.0 for analysis. Severe anemia was defined as hemoglobin ≤8.5 mg/dL. We included 203 patients: 132 treated with telaprevir (TVR) and 71 treated with boceprevir (BOC). AE-related treatment discontinuation rate was 19.2% and anemia was the main reason (38.5%). Risk factors for treatment discontinuation were higher comorbidity index (OR=1.85, CI=1.05-3.25) for BOC, and higher bilirubin count (OR=1.02, CI=1.01-1.04) and lower BMI (OR=0.98, CI=0.96-0.99) for TVR. Severe anemia occurred in 35 (17.2%) patients. Risk factors for this outcome were lower estimated glomerular filtration rate (eGFR; OR=0.95, CI=0.91-0.98) for patients treated with TVR, and higher comorbidity index (OR=2.21, CI=1.04-4.67) and ribavirin dosage (OR=0.84, CI=0.72-0.99) for those treated with BOC. Fifty-five (57.3%) patients treated with TVR and 15 (27.3%) patients treated with BOC achieved sustained virological response (SVR). Among patients who received TVR and interrupted treatment due to AE (n=19), only 26.3% (n=5) achieved SVR (P=0.003). Higher number of comorbidities, lower eGFR and advanced liver disease are associated with severe anemia and early treatment cessation, which may compromise SVR achievement.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Adulto Jovem , Anemia/etiologia , Hepatite C Crônica/tratamento farmacológico , Oligopeptídeos/administração & dosagem , Prolina/análogos & derivados , Inibidores de Proteases/administração & dosagem , Antivirais/administração & dosagem , Taxa de Filtração Glomerular , Hepatite C Crônica/complicações , Hepatite C Crônica/virologia , Interferon-alfa/administração & dosagem , Modelos Logísticos , Oligopeptídeos/efeitos adversos , Polietilenoglicóis/administração & dosagem , Prolina/administração & dosagem , Prolina/efeitos adversos , Estudos Prospectivos , Inibidores de Proteases/efeitos adversos , Proteínas Recombinantes/administração & dosagem , Ribavirina/administração & dosagem , Fatores de Risco , Índice de Gravidade de Doença , Estatísticas não Paramétricas , Resposta Viral Sustentada , Fatores de Tempo , Falha de Tratamento
20.
Rev. Esc. Enferm. USP ; 49(6): 937-943, Dec. 2015. graf
Artigo em Português | LILACS, BDENF - Enfermagem | ID: lil-767809

RESUMO

Abstract OBJECTIVE Comparing Health-Related Quality of Life (HRQoL) scores in patients with chronic hepatitis C undergoing double and triple antiviral therapy and analyzing possible factors related to HRQoL. METHOD HRQoL was assessed using the Short Form 36 and Chronic Liver Disease Questionnaire, which were applied at baseline and at weeks 4, 12 and 16 of treatment to 32 patients divided into two groups: double therapy with pegylated interferon (IFN-PEG) and ribavirin, and triple therapy with PEG-IFN, ribavirin and telaprevir. RESULTS The reduction of HRQoL was greater in patients receiving triple therapy compared to those treated with two drugs, the most critical time is at 12 weeks in both groups. After removal of telaprevir, the triple therapy group significantly improved their HRQoL scores. Anxiety and depression before treatment, employment status and race are significantly related to diminished HRQoL. CONCLUSION Patients undergoing double and triple therapy have diminished HRQoL indexes, but the addition of telaprevir chooses a more significant decrease.


Resumen OBJETIVO Comparar los puntajes de Calidad de Vida Relacionada con la Salud (CVRS) en pacientes con hepatitis C crónica sometidos a la terapia antiviral doble y triple y analizar los posibles factores relacionados con la CVRS. MÉTODO La CVRS fue evaluada utilizando el Short Form 36 y elChronic Liver Disease Questionnaire , que fueron aplicados antes y en las semanas 4, 12 y 16 de tratamiento, en 32 pacientes divididos en 2 grupos: terapia doble con interferón pegilado (IFN-PEG) y ribavirina, y triple con IFN-PEG, ribavirina y telaprevir. RESULTADOS La reducción de la CVRS fue mayor en pacientes en terapia triple cuando comparados con los tratados con dos drogas, siendo el momento más crítico la 12ª semana en ambos grupos. Después de la retirada del telaprevir, el grupo de terapia triple mejoró de modo significativo los puntajes de CVRS. Ansiedad y depresión en el pre tratamiento, situación de empleo y raza se mostraron relacionados con la reducción de la CVRS. CONCLUSIÓN Pacientes sometidos a la terapia doble y triple presentan reducción de los índices de CVRS, pero la adición del telaprevir les proporciona una caída más expresiva.


Resumo OBJETIVO Comparar os escores de Qualidade de Vida Relacionada à Saúde (QVRS) em pacientes com hepatite crônica C submetidos à terapia antiviral dupla e tripla e analisar os possíveis fatores relacionados à QVRS. MÉTODO A QVRS foi avaliada utilizando o Short Form 36 e oChronic Liver Disease Questionnaire , que foram aplicados antes e nas semanas 4, 12 e 16 de tratamento, em 32 pacientes divididos em 2 grupos: terapia dupla com interferon peguilado (IFN-PEG) e ribavirina e tripla com IFN-PEG, ribavirina e telaprevir. RESULTADOS A redução da QVRS foi maior em pacientes em terapia tripla quando comparados àqueles tratados com duas drogas, sendo o momento mais crítico a 12ª semana em ambos os grupos. Após a retirada do telaprevir, o grupo terapia tripla melhorou de modo significativo os escores de QVRS. Ansiedade e depressão no pré-tratamento, status empregatício e raça se mostraram relacionados à redução da QVRS. CONCLUSÃO Pacientes submetidos à terapia dupla e tripla apresentam redução dos índices de QVRS, mas a adição do telaprevir confere uma queda mais expressiva.


Assuntos
Feminino , Humanos , Masculino , Antivirais/administração & dosagem , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/administração & dosagem , Oligopeptídeos/administração & dosagem , Polietilenoglicóis/administração & dosagem , Qualidade de Vida , Ribavirina/administração & dosagem , Quimioterapia Combinada , Proteínas Recombinantes/administração & dosagem
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