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1.
Int J Mol Sci ; 25(3)2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38338681

RESUMO

Selenium has been proven to influence several biological functions, showing to be an essential micronutrient. The functional studies demonstrated the benefits of a balanced selenium diet and how its deficiency is associated with diverse diseases, especially cancer and viral diseases. Selenium is an antioxidant, protecting the cells from damage, enhancing the immune system response, preventing cardiovascular diseases, and decreasing inflammation. Selenium can be found in its inorganic and organic forms, and its main form in the cells is the selenocysteine incorporated into selenoproteins. Twenty-five selenoproteins are currently known in the human genome: glutathione peroxidases, iodothyronine deiodinases, thioredoxin reductases, selenophosphate synthetase, and other selenoproteins. These proteins lead to the transport of selenium in the tissues, protect against oxidative damage, contribute to the stress of the endoplasmic reticulum, and control inflammation. Due to these functions, there has been growing interest in the influence of polymorphisms in selenoproteins in the last two decades. Selenoproteins' gene polymorphisms may influence protein structure and selenium concentration in plasma and its absorption and even impact the development and progression of certain diseases. This review aims to elucidate the role of selenoproteins and understand how their gene polymorphisms can influence the balance of physiological conditions. In this polymorphism review, we focused on the PubMed database, with only articles published in English between 2003 and 2023. The keywords used were "selenoprotein" and "polymorphism". Articles that did not approach the theme subject were excluded. Selenium and selenoproteins still have a long way to go in molecular studies, and several works demonstrated the importance of their polymorphisms as a risk biomarker for some diseases, especially cardiovascular and thyroid diseases, diabetes, and cancer.


Assuntos
Neoplasias , Selênio , Humanos , Selênio/metabolismo , Selenoproteínas/genética , Selenoproteínas/metabolismo , Inflamação/genética , Neoplasias/genética , Biomarcadores
2.
Mem Inst Oswaldo Cruz ; 118: e230115, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38126526

RESUMO

BACKGROUND: A positive Trypanosoma cruzi polymerase chain reaction (PCR) is associated with a worse prognosis in patients with chronic Chagas disease (CD). OBJECTIVES: To study the association of clinical, electrocardiographic, and echocardiographic characteristics and biomarker blood levels with positive T. cruzi PCR in chronic CD. METHODS: This is a single-centre observational cross-sectional study. Positive T. cruzi PCR association with clinical, electrocardiographic, and echocardiographic characteristics, and biomarker blood levels were studied by logistic regression analysis. p values < 0.05 were considered significant. FINDINGS: Among 333 patients with chronic CD (56.4% men; 62 ± 10 years), T. cruzi PCR was positive in 41.1%. Stepwise multivariate logistic regression showed an independent association between positive T. cruzi PCR and diabetes mellitus {odds ratio (OR) 0.53 [95% confidence interval (CI) 0.30-0.93]; p = 0.03}, right bundle branch block [OR 1.78 (95% CI 1.09-2.89); p = 0.02], and history of trypanocidal treatment [OR 0.13 (95% CI 0.04-0.38); p = 0.0002]. Among patients with a history of trypanocidal treatment (n = 39), only four (10%) patients had a positive T. cruzi PCR. MAIN CONCLUSIONS: Among several studied parameters, only diabetes mellitus, right bundle branch block, and history of trypanocidal treatment showed an independent association with positive T. cruzi PCR. History of trypanocidal treatment was a strong protective factor against a positive T. cruzi PCR.


Assuntos
Doença de Chagas , Diabetes Mellitus , Tripanossomicidas , Trypanosoma cruzi , Feminino , Humanos , Masculino , Biomarcadores , Bloqueio de Ramo/complicações , Bloqueio de Ramo/tratamento farmacológico , Doença de Chagas/tratamento farmacológico , Doença Crônica , Estudos Transversais , Diabetes Mellitus/tratamento farmacológico , Reação em Cadeia da Polimerase , Tripanossomicidas/uso terapêutico , Trypanosoma cruzi/genética , Pessoa de Meia-Idade , Idoso
3.
J Dairy Res ; 90(4): 376-381, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38186216

RESUMO

This research paper presents the development and evaluation of pioneering nanocomposites (NCs) based on the combination of k-carrageenan and linseed mucilage. When loaded with macela extract nanoemulsion they present an innovative approach for the sustained release of antimicrobial herbal constituents, specifically tailored for bovine mastitis treatment. The NCs, encompassing various ratios of k-carrageenan and linseed mucilage polymers (8:2, 7:3, and 5:5 w/w) with 1.25 mg of macela extract/g of gel, underwent in vitro assessment, emphasizing viscosity, degradation speed, release of herbal actives from macela nanoemulsion and antimicrobial activity. The NCs exhibited thermoreversible characteristics, transitioning from liquid at 60°C to a gel at 25°C. NCs allowed a gradual release of phenolic compounds, reaching approximately 80% of total phenolics release (w/v) within 72 h. NCs inhibited the growth of MRSA (ATCC 33592) until 8 h of incubation. No toxic effect in vitro of NCs was found on MAC-T cells. Thus, the developed materials are relevant for the treatment of bovine mastitis, especially in the dry period, and the data support future evaluations in vivo.


Assuntos
Achyrocline , Anti-Infecciosos , Doenças dos Bovinos , Linho , Mastite Bovina , Nanocompostos , Feminino , Bovinos , Animais , Carragenina , Mastite Bovina/tratamento farmacológico , Óleo de Semente do Linho , Extratos Vegetais/farmacologia
4.
Mem Inst Oswaldo Cruz ; 117: e220001, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35319676

RESUMO

Translational research (TR) is an interdisciplinary branch of the biomedical field that seeks to connect its three supporting pillars: basic research on the bench, the hospital beds and other health system services, and the delivery of products for the well-being and health of the community. Here, we review the five transition stages of the TR spectrum, registering the lessons learned during > 20 years leading to the first clinical trial designed and performed in Brazil for testing a complementary treatment for Chagas disease (CD): the selenium trial (STCC). Lessons learned were: (1) to consider all the TR spectrum since the beginning of the project; (2) to start simultaneously animal studies and translation to humans; (3) to ensure a harmonious interaction between clinical and basic research teams; (4) to include MSc and PhD students only in pre-clinical and basic studies (TR0) or vertical clinical studies using retrospective samples and data (TR1); (5) to identify potential suppliers in the national commercial market for a future final treatment since the pre-clinical stage; (6) to keep an international network of experts as permanent advisers on the project. In the whole process, some perspectives were created: a complementary clinical trial for the opened questions and the construction of a Brazilian clinical CD platform.


Assuntos
Doença de Chagas , Selênio , Animais , Doença de Chagas/tratamento farmacológico , Suplementos Nutricionais , Humanos , Estudos Retrospectivos , Selênio/uso terapêutico , Pesquisa Translacional Biomédica
5.
Mem Inst Oswaldo Cruz ; 117: e210395, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35239842

RESUMO

Transforming growth factor beta (TGF-ß) is deeply involved on the pathogenesis of Chagas disease. Our group has been investigating the participation of this pleiotropic cytokine in different aspects of Chagas disease over the last 20 years. Important observations have been made, such as: (i) the ability of Trypanosoma cruzi in activating latent TGF-ß; (ii) the potential involvement of TGF-ß pathway on T. cruzi invasion of host cells; (iii) association of TGF-ß with parasite intracellular replication; (iv) cardiac fibrosis development and maintenance; (v) disruption of Connexin-43 plaque structures and (vi) inflammation and immune response. In this perspective article we intend to discuss the advances of the potential use of new therapies targeting TGF-ß to treat the cardiac alterations of Chagas disease-affected patients.


Assuntos
Cardiomiopatia Chagásica , Trypanosoma cruzi , Cardiomiopatia Chagásica/tratamento farmacológico , Cardiomiopatia Chagásica/metabolismo , Coração , Humanos , Miocárdio/patologia , Fator de Crescimento Transformador beta/antagonistas & inibidores , Trypanosoma cruzi/fisiologia
6.
Mem Inst Oswaldo Cruz ; 117: e220005, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36417626

RESUMO

BACKGROUND: Angiogenesis has been implicated in tissue injury in several noninfectious diseases, but its role in Chagas disease (CD) physiopathology is unclear. OBJECTIVES: The present study aimed to investigate the effect of Trypanosoma cruzi infection on cardiac angiogenesis during the acute phase of experimental CD. METHODS: The signalling pathway involved in blood vessel formation and cardiac remodelling was evaluated in Swiss Webster mice infected with the Y strain of T. cruzi. The levels of molecules involved in the regulation of angiogenesis, such as vascular endothelial growth factor-A (VEGF-A), Flk-1, phosphorylated extracellular-signal-regulated protein kinase (pERK), hypoxia-inducible factor-1α (HIF-1α), CD31, α-smooth muscle actin (α-SMA) and also the blood vessel growth were analysed during T. cruzi infection. Hearts were analysed using conventional histopathology, immunohistochemistry and western blotting. FINDINGS: In this study, our data demonstrate that T. cruzi acute infection in mice induces exacerbated angiogenesis in the heart and parallels cardiac remodelling. In comparison with noninfected controls, the cardiac tissue of T. cruzi-infected mice presented higher levels of (i) HIF-1α, VEGF-A, Flk-1 and pERK; (ii) angiogenesis; (iii) α-SMA+ cells in the tissue; and (iv) collagen -1 deposition around blood vessels and infiltrating throughout the myocardium. MAIN CONCLUSIONS: We observed cardiac angiogenesis during acute experimental T. cruzi infection parallels cardiac inflammation and remodelling.


Assuntos
Doença de Chagas , Fator A de Crescimento do Endotélio Vascular , Camundongos , Animais , Fator A de Crescimento do Endotélio Vascular/metabolismo , Remodelação Ventricular , Doença de Chagas/metabolismo , Coração , Miocárdio/patologia
7.
J Dairy Res ; : 1-6, 2022 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-35225191

RESUMO

The low levels of toxicity and cytoprotective effect attributed to Achyrocline satureioides (Lam.) DC, a medicinal plant native to South America, are of interest for bovine mastitis therapy. This research paper reports the hypothesis that a nanoemulsion of macela extract (Achyrocline satureioides) exerts protective effects on bovine mammary alveolar cells -T (MAC-T) and increases the permeation of flavonoid compounds through mammary epithelium. Extract-loaded nanoemulsions (2.5 mg/ml) (NE-ML) (n = 4) were prepared using high-pressure homogenization with varying concentrations of flaxseed oil and Tween 80. Permeation and retention of free and nanoencapsulated quercetin, 3-O-methylquercetin and luteolin were performed on mammary glandular epithelium using Franz diffusion cells. The cell viability was evaluated on mammary epithelial cells (MAC-T lineage) using the MTT method (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) after exposure to loaded and blank nanoemulsions (NE-ML and NE-BL). Necrotic or apoptotic cell death was evaluated by flow cytometry after exposure to nanoemulsions (NE-ML and NE-BL). Subsequently, the cell death was assessed by previously treating MAC-T cells with NE-ML for 23 h, followed by exposure to H2O2 (2 mM) for 1 h. Higher permeation of quercetin and 3-O-methylquercetin in NE-ML was found compared to that of free extract with a final permeated amount of 50.7 ± 3.2 and 111.2 ± 0.6 µg/cm2 compared to 35.0 ± 0.6 and 48.9 ± 1.2, respectively. For NE-BL, the IC50 was at least 1.3% (v/v), while for the NE-ML, it was at least 2.6% (v/v). After exposure to NE-ML (5 and 1.2%, v/v), the percentage of apoptotic cells was reduced (±30%). For the H2O2 assay, the percentage of cells in necrosis was reduced by 40% after exposure to NE-ML1% (v/v) + H2O2 2 mM. The protective effects and increased permeation of macela nanoemulsion make this a promising new candidate for bovine mastitis therapy.

8.
J Psycholinguist Res ; 51(2): 309-322, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35122567

RESUMO

The present study investigated the effect of emotional valence on auditory word recognition memory in English as a foreign language. Participants included 48 native Spanish speakers whose foreign language was English. They viewed four emotionally negative, four positive, and four neutral videos that, in total, contained 48 emotionally valenced target words. After watching the videos, participants completed an auditory word recognition memory task where target words, and the same number of fillers, were presented. The results showed a statistically significant main effect of valence on both reaction times and accuracy. Positive words were recognised more accurately and faster than neutral and negative words, but no difference between neutral and negative stimuli was found. These findings fit in well within the gradient model of automatic vigilance, which implies that emotional valence has a monotonic effect on processing latencies during auditory recognition memory in a foreign language.


Assuntos
Emoções , Idioma , Humanos , Tempo de Reação , Reconhecimento Psicológico
9.
Br J Clin Pharmacol ; 86(1): 143-154, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31659776

RESUMO

AIMS: Chronic Chagas disease (ChD) has high morbimortality and loss in quality of life due to heart failure (HF). Pharmaceutical care (PC) optimizes clinical treatment and can improve quality of life in HF. We evaluated if PC improves quality of life of patients with ChD and HF. METHODS: Single-blinded, randomized, controlled trial that assigned adult patients with ChD and HF (81 patients; 61 ± 11 years; 48% male) to PC (n = 40) or standard care (n = 41). Quality of life according to SF-36 and Minnesota living with HF questionnaires, incidence of drug-related problems (DRPs), and adherence to medical treatment were determined at baseline and at every 3 months for 1 year. Intention-to-treat analyses were performed by mixed linear model to verify the treatment effect on the changes of these variables throughout the intervention period. RESULTS: Relative changes from baseline to 1 year of follow-up of the domains physical functioning (+16.6 vs -8.5; P < .001), role-physical (+34.0 vs +5.2; P = .01), general health (+19.4 vs -6.1; P < .001), vitality (+11.5 vs. -5.8; P = .003), social functioning (+7.5 vs -13.3; P = .002), and mental health (+9.0 vs -3.7; P = .006) of the SF-36 questionnaire and the Minnesota living with HF questionnaire score (-12.7 vs +4.8; P < .001) were superior in the PC group than in the standard care group. Adherence to medical treatment increased as early as after 3 months of follow-up and DRPs incidence decreased after 6 months of follow-up only in the PC group. CONCLUSIONS: Patients with ChD and HF who received PC presented improved quality of life, decrease in DRP frequency, and increase in medication adherence.


Assuntos
Doença de Chagas , Insuficiência Cardíaca , Assistência Farmacêutica , Adulto , Feminino , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/epidemiologia , Humanos , Masculino , Qualidade de Vida , Inquéritos e Questionários
11.
Mem Inst Oswaldo Cruz ; 113(4): e170440, 2018 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-29513876

RESUMO

BACKGROUND: Transforming growth factor ß1 (TGF-ß1) and tumour necrosis factor (TNF) have been implicated in Chagas disease pathophysiology and may correlate with left ventricular (LV) function. OBJECTIVES: We determined whether TGF-ß1 and TNF serum levels correlate with LV systolic and diastolic functions and brain natriuretic peptide (BNP) serum levels in chronic Chagas disease. METHODS: This cross-sectional study included 152 patients with Chagas disease (43% men; 57 ± 12 years old), classified as 53 patients with indeterminate form and 99 patients with cardiac form (stage A: 24, stage B: 25, stage C: 44, stage D: 6). TGF-ß1, TNF, and BNP were determined by enzyme-linked immunosorbent assay ELISA. Echocardiogram was used to determine left atrial and LV diameters, as well as LV ejection fraction and diastolic function. FINDINGS: TGF-b1 serum levels were lower in stages B, C, and D, while TNF serum levels were higher in stages C and D of the cardiac form. TGF-ß1 presented a weak correlation with LV diastolic function and LV ejection fraction. TNF presented a weak correlation with left atrial and LV diameters and LV ejection fraction. CONCLUSIONS: TNF is increased, while TGF-ß1 is decreased in the cardiac form of chronic Chagas disease. TNF and TGF-ß1 serum levels present a weak correlation with LV systolic and diastolic function in Chagas disease patients.


Assuntos
Doença de Chagas/sangue , Doença de Chagas/fisiopatologia , Peptídeo Natriurético Encefálico/sangue , Fator de Crescimento Transformador beta1/sangue , Fatores de Necrose Tumoral/sangue , Função Ventricular Esquerda/fisiologia , Adulto , Idoso , Estudos de Casos e Controles , Estudos Transversais , Diástole/fisiologia , Ecocardiografia , Eletrocardiografia , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Índice de Gravidade de Doença , Estatísticas não Paramétricas , Sístole/fisiologia
12.
Trop Med Int Health ; 22(10): 1314-1321, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28805026

RESUMO

OBJECTIVES: To evaluate the correlation of the total distance walked during the six-minute walk test (6MWT) with left ventricular function and quality of life in patients with Chagas Disease (ChD) complicated by heart failure. METHODS: This is a cross-sectional study of adult patients with ChD and heart failure diagnosed based on Framingham criteria. 6MWT was performed following international guidelines. New York Heart Association functional class, brain natriuretic peptide (BNP) serum levels, echocardiographic parameters and quality of life (SF-36 and MLHFQ questionnaires) were determined and their correlation with the distance covered at the 6MWT was tested. RESULTS: Forty adult patients (19 male; 60 ± 12 years old) with ChD and heart failure were included in this study. The mean left ventricular ejection fraction was 35 ± 12%. Only two patients (5%) ceased walking before 6 min had elapsed. There were no cardiac events during the test. The average distance covered was 337 ± 105 metres. The distance covered presented a negative correlation with BNP (r = -0.37; P = 0.02), MLHFQ quality-of-life score (r = -0.54; P = 0.002), pulmonary artery systolic pressure (r = -0.42; P = 0.02) and the degree of diastolic dysfunction (r = -0.36; P = 0.03) and mitral regurgitation (r = -0.53; P = 0.0006) and positive correlation with several domains of the SF-36 questionnaire. CONCLUSIONS: The distance walked during the 6MWT correlates with BNP, quality of life and parameters of left ventricular diastolic function in ChD patients with heart failure. We propose this test to be adopted in endemic areas with limited resources to aid in the identification of patients who need referral for tertiary centres for further evaluation and treatment.


Assuntos
Doença de Chagas/complicações , Insuficiência Cardíaca/fisiopatologia , Qualidade de Vida , Função Ventricular Esquerda/fisiologia , Teste de Caminhada , Doença de Chagas/fisiopatologia , Estudos Transversais , Ecocardiografia , Feminino , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/etiologia , Humanos , Técnicas Imunoenzimáticas , Masculino , Pessoa de Meia-Idade , Peptídeo Natriurético Encefálico/análise
14.
Rev Col Bras Cir ; 51: e20243791, 2024.
Artigo em Inglês, Português | MEDLINE | ID: mdl-39258627

RESUMO

The role of the burn surgeon in Burn Treatment Centers (BTCs) is crucial for complementing the multidisciplinary approach in the treatment of burn patients. Globally, the areas of General Surgery and Plastic Surgery are the primary surgical specialties dedicated to this function. The structuring of the Burn Patient Care Line in Minas Gerais highlighted the need to expand the "Burn Care" Field of Expertise, extending it to General Surgery. With the inevitable expansion of the Care Line, pioneered by the state of Minas Gerais, to the federal level, the need for specialized surgical training encompasses both the state context and anticipates the national scenario in the short term. Therefore, the expansion of the "Burn Care" Field of Expertise is fundamental to meeting specific demands and improving the quality of care offered to burn patients, in accordance with international standarts.


Assuntos
Queimaduras , Brasil , Queimaduras/terapia , Humanos , Cirurgia Geral/educação , Unidades de Queimados/organização & administração , Cirurgiões
15.
Biology (Basel) ; 13(7)2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-39056658

RESUMO

Breast cancer is the most prevalent cancer among women worldwide. Therapeutic strategies to control tumors and metastasis are still challenging. Three-dimensional (3D) spheroid-type systems more accurately replicate the features of tumors in vivo, working as a better platform for performing therapeutic response analysis. This work aimed to characterize the epithelial-mesenchymal transition and doxorubicin (dox) response in a mammary tumor spheroid (MTS) model. We evaluated the doxorubicin treatment effect on MCF-7 spheroid diameter, cell viability, death, migration and proteins involved in the epithelial-mesenchymal transition (EMT) process. Spheroids were also produced from tumors formed from 4T1 and 67NR cell lines. MTSs mimicked avascular tumor characteristics, exhibited adherens junction proteins and independently produced their own extracellular matrix. Our spheroid model supports the 3D culturing of cells isolated from mice mammary tumors. Through the migration assay, we verified a reduction in E-cadherin expression and an increase in vimentin expression as the cells became more distant from spheroids. Dox promoted cytotoxicity in MTSs and inhibited cell migration and the EMT process. These results suggest, for the first time, that this model reproduces aspects of the EMT process and describes the potential of dox in inhibiting the metastatic process, which can be further explored.

16.
Biology (Basel) ; 13(5)2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38785783

RESUMO

Neurological commitment is a neglected manifestation of Chagas disease (CD). Meningoencephalitis mainly affects children and immunosuppressed patients, while stroke can occur with or without cardiac compromise. One of the possible causes of stroke development is microvascular commitment. Our group previously described that experimental Trypanossoma cruzi acute infection leads to cerebral microvasculopathy. This condition is characterized by decreased capillary density, increased leukocyte rolling and adhesion, and endothelial dysfunction. CD was discovered 114 years ago, and until today, only two drugs have been available for clinical treatment: benznidazole and nifurtimox. Both present a high cure rate for the acute phase (80%) and small cure rate for the chronic phase (20%). In addition, the high occurrence of side-effects, without proper medical follow-up, can result in treatment abandonment. Therefore, the search for new therapeutic schemes is necessary. Statins are drugs already used in the clinic that have several pleiotropic effects including endothelial function improvement, anti-inflammatory action, as well as trypanocidal effects, making them a potential alternative treatment for brain microvasculopathy in CD. Here, we investigate the effect of lovastatin (LOV) on brain microvasculopathy and inflammatory parameters. Swiss Webster mice were intraperitoneally inoculated with the Y strain of T. cruzi. Treatment with lovastatin (20 mg/kg/day) was initiated 24 h after the infection and continued for 14 consecutive days. We observed that LOV treatment did not affect parasitemia, brain microcirculation alterations, or the reduction in cerebral blood flow caused by T. cruzi infection. Also, LOV did not prevent the increased number of CD3+ cells and eNOS levels in the T. cruzi-infected brain. No alterations were observed on VCAM-1 and MCP-1 expressions, neither caused by infection nor LOV treatment. However, LOV prevented the increase in F4/80+ cells and ICAM-1 levels in the brain caused by acute infection with T. cruzi. These results suggest an anti-inflammatory activity of LOV, but more studies are needed to elucidate the role of LOV in CD acute infection.

17.
PLoS Negl Trop Dis ; 18(8): e0012166, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39146233

RESUMO

Chagas disease, caused by the parasite Trypanosoma cruzi, affects over 6 million people, mainly in Latin America. Two different clinical phases, acute and chronic, are recognised. Currently, 2 anti-parasitic drugs are available to treat the disease (nifurtimox and benznidazole), but diagnostic methods require of a relatively complex infrastructure and trained personnel, limiting its widespread use in endemic areas, and the access of patients to treatment. New diagnostic methods, such as rapid tests (RDTs) to diagnose chronic Chagas disease, or loop-mediated isothermal amplification (LAMP), to detect acute infections, represent valuable alternatives, but the parasite's remarkable genetic diversity might make its implementation difficult. Furthermore, determining the efficacy of Chagas disease treatment is complicated, given the slow reversion of serological anti-T. cruzi antibody reactivity, which may even take decades to occur. New biomarkers to evaluate early therapeutic efficacy, as well as diagnostic tests able to detect the wide variety of circulating genotypes, are therefore, urgently required. To carry out studies that address these needs, high-quality and traceable samples from T. cruzi-infected individuals with different geographical backgrounds, along with associated clinical and epidemiological data, are necessary. This work describes the framework for the creation of such repositories, following standardised and uniform protocols, and considering the ethical, technical, and logistic aspects of the process. The manual can be adapted according to the resources of each laboratory, to guarantee that samples are obtained in a reproducible way, favouring the exchange of data among different work groups, and their generalizable evaluation and analysis. The main objective of this is to accelerate the development of new diagnostic methods and the identification of biomarkers for Chagas disease.


Assuntos
Doença de Chagas , Trypanosoma cruzi , Doença de Chagas/diagnóstico , Humanos , Trypanosoma cruzi/genética , Bancos de Espécimes Biológicos , Técnicas de Amplificação de Ácido Nucleico/métodos
18.
Front Microbiol ; 14: 1295017, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38188583

RESUMO

Chagas disease (CD) is caused by the flagellate protozoan Trypanosoma cruzi. It is endemic in Latin America. Nowadays around 6 million people are affected worldwide, and 75 million are still at risk. CD has two evolutive phases, acute and chronic. The acute phase is mostly asymptomatic, or presenting unspecific symptoms which makes it hard to diagnose. At the chronic phase, patients can stay in the indeterminate form or develop cardiac and/or digestive manifestations. The two trypanocide drugs available for the treatment of CD are benznidazole (BZ) and nifurtimox (NFX), introduced in the clinic more than five decades ago. WHO recommends treatment for patients at the acute phase, at risk of congenital infection, for immunosuppressed patients and children with chronic infection. A high cure rate is seen at the CD acute phase but better treatment schemes still need to be investigated for the chronic phase. There are some limitations within the use of the trypanocide drugs, with side effects occurring in about 40% of the patients, that can lead patients to interrupt treatment. In addition, patients with advanced heart problems should not be treated with BZ. This is a neglected disease, discovered 114 years ago that still has no drug effective for their chronic phase. Multiple social economic and cultural barriers influence CD research. The high cost of the development of new drugs, in addition to the low economical return, results in the lack of investment. More economic support is required from governments and pharmaceutical companies on the development of more research for CD treatment. Two approaches stand out: repositioning and combination of drugs, witch drastically decrease the cost of this process, when compared to the development of a new drug. Here we discuss the progress of the clinical trials for the etiological and pathophysiological treatment for CD. In summary, more studies are needed to propose a new drug for CD. Therefore, BZ is still the best option for CD. The trials in course should clarify more about new treatment regimens, but it is already possible to indicate that dosage and time of treatment need to be adjusted.

19.
Biology (Basel) ; 12(11)2023 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-37998013

RESUMO

Chagas disease (CD) caused by Trypanosoma cruzi is a neglected illness and a major reason for cardiomyopathy in endemic areas. The existing therapy generally involves trypanocidal agents and therapies that control cardiac alterations. However, there is no treatment for the progressive cardiac remodeling that is characterized by inflammation, microvasculopathy and extensive fibrosis. Thus, the search for new therapeutic strategies aiming to inhibit the progression of cardiac injury and failure is necessary. Vascular Endothelial Growth Factor A (VEGF-A) is the most potent regulator of vasculogenesis and angiogenesis and has been implicated in inducing exacerbated angiogenesis and fibrosis in chronic inflammatory diseases. Since cardiac microvasculopathy in CD is also characterized by exacerbated angiogenesis, we investigated the effect of inhibition of the VEGF signaling pathway using a monoclonal antibody (bevacizumab) on cardiac remodeling and function. Swiss Webster mice were infected with Y strain, and cardiac morphological and molecular analyses were performed. We found that bevacizumab significantly increased survival, reduced inflammation, improved cardiac electrical function, diminished angiogenesis, decreased myofibroblasts in cardiac tissue and restored collagen levels. This work shows that VEGF is involved in cardiac microvasculopathy and fibrosis in CD and the inhibition of this factor could be a potential therapeutic strategy for CD.

20.
J Am Heart Assoc ; 12(12): e028810, 2023 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-37313975

RESUMO

Background Chagas disease (CD) presents an ominous prognosis. The predictive value of biomarkers and new echocardiogram parameters in adjusted models have not been well studied. Methods and Results There were 361 patients with chronic CD (57.6% men, 61±11 years of age, clinical forms: indeterminate 27.1%, cardiac 56.6%, digestive 3.6%, cardiodigestive 12.7%) included in this single-center, observational, prospective longitudinal study. Echocardiographic evaluation included strain analyses of left atrial, left ventricular (LV), and right ventricular and 3-dimensional analyses of left atrial and LV volumes. Biomarkers included cardiac troponin I, brain natriuretic peptide, transforming growth factor ß1, tumor necrosis factor, matrix metalloproteinases, and Trypanosoma cruzi polymerase chain reaction. The studied end point was a composite of CD-related mortality, heart transplant, hospital admission due to worsening heart failure, or new cardiac device insertion. Event-free survival was analyzed by multivariable regression analyses adjusted for competing risks. P values <0.05 were considered significant. The composite event occurred in 79 patients after 4.9±2.0 years follow-up. LV end-diastolic volume (hazard ratio [HR], 1.01 [95% CI, 1.00-1.02]; P=0.02), peak negative global atrial strain (HR, 1.08 [95% CI, 1.00-1.17]; P=0.04), LV global circumferential strain (HR, 1.12 [95% CI, 1.04-1.21]; P=0.003), LV torsion (HR, 0.55 [95% CI, 0.35-0.81]; P=0.003), brain natriuretic peptide (HR, 2.03 [95% CI, 1.23-3.34]; P=0.005), and positive T cruzi polymerase chain reaction (HR, 1.80 [95% CI, 1.12-2.91]; P=0.01) were end point predictors independent from age, sex, 2-dimensional echocardiographic indexes, hypertension, previous cardiac device, and CD cardiac form. Conclusions Two-dimensional strain- and 3-dimensional-derived parameters, brain natriuretic peptide, and positive T cruzi polymerase chain reaction can be useful for prediction of CD cardiovascular events.


Assuntos
Fibrilação Atrial , Doença de Chagas , Masculino , Humanos , Feminino , Estudos Longitudinais , Estudos Prospectivos , Peptídeo Natriurético Encefálico , Ecocardiografia/métodos , Biomarcadores , Prognóstico , Doença de Chagas/complicações , Função Ventricular Esquerda , Volume Sistólico
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