Navegando por Autor "Teixeira, Luiz Fernando de Medeiros"

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Additive effects of resveratrol and doxorubicin on bladder cancer cells.
(2022) Soares, Luciana Bicalho Moreira; Lima, Ana Paula Braga; Melo, André Sacramento; Almeida, Tamires Cunha; Teixeira, Luiz Fernando de Medeiros; Silva, Glenda Nicioli da
The treatment of bladder cancer remains a challenge in clinical practice. Different chemotherapeutic protocols can be used; however, it is common to observe tumor recurrence and secondary effects that result in toxicity. Doxorubicin (DOX), one of the most effective anticancer agents used to treat bladder cancer, can cause chronic cardiotoxicity, limiting its use in clinical practice. Resveratrol (RES), a natural product with potential antitumor activity against bladder cancer, is associated with rapid metabolism and low bioavailability and needs to be combined with chemotherapeutic drugs to improve its use. Our study aimed to assess the therapeutic effect of a low concentration of DOX (2µM) in combination with RES (150, 200 and 250µM) on two bladder cancer cell lines. We investigated the mechanism of interaction between the drugs by performing cytotoxicity, clonogenic, oxidative stress, cell migration, cell morphology and nuclear division index (NDI) assays. Cytotoxicity evaluation revealed an additive interaction between RES and DOX for both cell lines. Additionally, the results of cell colony formation, oxidative stress, cell migration, cell morphology and NDI assays showed that a combination of DOX and RES was more effective than RES or DOX alone. In conclusion, a low concentration of DOX combined with RES could potentiate the antitumor effects of the drugs on bladder cancer cells, thus overcoming the secondary effects caused by DOX and the low bioavailability of resveratrol.
Análise fitoquímica e bioprospecção para atividade antimicrobiana de Protium spruceanum (Benth.) Engler.
(2016) Amparo, Tatiane Roquete; Souza, Gustavo Henrique Bianco de; Teixeira, Luiz Fernando de Medeiros; Brandão, Geraldo Célio; Vieira Filho, Sidney Augusto
Devido ao crescimento de patógenos resistentes aos fármacos atuais, a pesquisa por novos antimicrobianos tem sido incentivada, principalmente através das plantas medicinais. A espécie vegetal Protium spruceanum (Benth.) Engler, conhecida como breu, é utilizada popularmente como antiinflamatório e expectorante, porém, há necessidade de expandir estudos sobre essa espécie. Dessa forma, os objetivos desse estudo foram a avaliação da atividade antimicrobiana e o estudo fiquímico dos extratos etanólicos brutos (EEBs) e frações de folhas e galhos de P. spruceanum. Através dos métodos de difusão em poço e microdiluição, observou-se a atividade antimicrobiana dos EEBs contra 20 micro-organismos. O EEB de folhas apresentou maior atividade antimicrobiana total (AAT) que o EEB de galhos. As frações mais ativas foram as acetatoetilênicas e hidrometanólicas que apresentam ação sinérgica entre si. Através do estudo fitoquímico, observou-se que a AAT dos EEBs e frações pode ser corelacionada majoritariamente ao teor de taninos totais, porém, propõe-se uma ação sinérgica com outros compostos, como flavonóides. Os constituintes voláteis majoritários foram identificados utilizando CG/EM, dentre eles ácidos graxos, fenólicos e terpenoides, como amirinas. A avaliação da mistura de α- e β-amirina mostrou que esta não apresenta forte atividade antimicrobiana e também não está relacionada ao sinergismo entre as frações. Através de CLUE/DAD/EM-EM também foi possível identificar flavonoides glicosilados (quercetina-3-O-ramnosídeo, quercetina-3-Oglicuronídeo e campeferol-3-O-ramnosídeo) e taninos (catequina e procianidina). Os resultados in silico gerados pela ferramenta PASSonline indicaram potencial efeito antibacteriano principalmente para os constituintes majoritários das frações AcOEt e HMeOH. Também foram indicados como principais mecanismos de ação: aumento da permebilidade da membrana celular, inibição da bissíntese da parede bacteriana (enzimas peptideoglicano glicosiltransferase e CDP-glicerol glicerofosfotransferase) e inibição do metabolismo (enzimas 2-deidropantoato 2-redutase e piruvato cinase). Esses mecanismos de ação são diferentes dos antibióticos recentes e são considerados alvos para novos fármacos.
Angiotensin‐converting enzyme gene (ACE) polymorphisms are associated with dysregulation of biochemical parameters in hypertensive patients.
(2023) Agostini, Lívia da Cunha; Cunha, Warlley Rosa; Silva, Nayara Nascimento Toledo; Melo, André Sacramento; Soares, Luciana Bicalho Moreira; Almeida, Tamires Cunha; Belo, Vanessa de Almeida; Vital, Wendel Coura; Teixeira, Luiz Fernando de Medeiros; Lima, Angélica Alves; Silva, Glenda Nicioli da
Introduction The genetic component, including genes and their variants, plays a signifcant role in the pathophysiology of arterial hypertension (AH). Thus, clinical, epidemiological and genetic studies have been carried out to improve the under- standing of disease mechanisms, improve diagnostic quality and contribute to prevention. Objective To determine the association of risk factors, biochemical parameters and diferent ACE gene polymorphisms with AH. Method The case-control study was carried out in the population of Ouro Preto, Brazil. The subjects answered a question- naire containing clinical and sociodemographic data. The ACE gene polymorphisms rs4291, rs4363 and rs4335 were evalu- ated by real time-polymerase chain reaction (real-time PCR) in 310 people (155 hypertensive and 155 normotensive patients), in addition to biochemical parameters. A multivariate logistic regression model was used to identify factors associated with AH. Analysis of continuous variables was performed using the Kruskal-Wallis test to assess signifcance between groups and Dunn’s post-test for multiple comparisons. Results The results showed that AH was associated with age, education, smoking, obesity and high levels of triglycerides, sodium, glucose and uric acid. Regarding the biochemical parameters, in hypertensive patients, the rs4363 and rs4335 poly- morphisms were associated with high levels of triglycerides, urea and glucose; the rs4291 polymorphism was associated with elevated urea and glucose levels. No association was detected between SNPs and HA. Conclusion AH was associated with socioeconomic status, lifestyle habits and biochemical parameters. ACE polymorphisms may have infuenced the levels of triglycerides, urea and glucose in hypertensive patients.
Antibacterial activity of extract and fractions from branches of Protium spruceanum and cytotoxicity on fibroblasts.
(2017) Amparo, Tatiane Roquete; Rodrigues, Ivanildes Vasconcelos; Seibert, Janaína Brandão; Souza, Rafaella Hilda Zaniti; Oliveira, Amanda Ribeiro de; Cabral, Vivette Appolinário Rodrigues; Vieira, Paula Melo de Abreu; Brandão, Geraldo Célio; Okuma, Adriana Akemi; Vieira Filho, Sidney Augusto; Teixeira, Luiz Fernando de Medeiros; Souza, Gustavo Henrique Bianco de
The crude ethanol extract (CEE) and fractions from branches of Protium spruceanum were subjected to antibacterial and cytotoxicity assays. Compounds of the most active fraction were identified by GC-MS and LC-MS. CEE was active against 19 bacteria and the ethyl acetate fraction (EAF) showed the lowest minimum bactericidal concentration (MBC 0.3–80.0 mg/mL). Through time-kill assay was observed that EAF induced rapid bactericidal effect against Staphylococcus saprophyticus. The cytotoxicity tests against L929 fibroblasts showed great potential of EAF on the treatment of infections caused by five bacteria (MBC < IC50). The results provide in vitro scientific support to the possible application of branches of P. spruceanum as antimicrobial agent that may contribute for treatment of infections.
Antibacterial substances from leaves of Protium spruceanum (Burseraceae) : in vitro and in silico evaluation.
(2020) Amparo, Tatiane Roquete; Rodrigues, Ivanildes Vasconcelos; Seibert, Janaína Brandão; Almeida, Tamires Cunha; Cabral, Vivette Appolinário Rodrigues; Vieira, Paula Melo de Abreu; Brandão, Geraldo Célio; Oliveira, Mauro Lúcio Gonçalves de; Silva, Glenda Nicioli da; Santos, Orlando David Henrique dos; Vieira Filho, Sidney Augusto; Teixeira, Luiz Fernando de Medeiros; Souza, Gustavo Henrique Bianco de
Due to the increase of bacterial resistance, the search for new antibiotics is necessary and the medicinal plants represent its most important source. The aim of this study was to evaluate the antibacterial property of extract and fractions from Protium spruceanum leaves, against pathogenic bacteria. By means of diffusion and microdilution assays, the crude extract was active against the nine bacteria tested being the hydromethanolic fraction the most active. During phytochemical procedures, procyanidin (1) and catechin (2) were identified as the main antibacterial constituents of this fraction. In silico results obtained using PASSonline tool indicated 1 and 2 as having good potential to interact with different targets of currently used antibiotics. These results no indicated potential to none DNA effect and indicated the cell wall as mainly target. Electrophoresis result supported that had no DNA damage. Cell wall damage was confirmed by propidium iodide test that showed increased membrane permeability and by cell surface deformations observed in scanning electronic microscopy. The in vitro assays together with the in silico prediction results establish the potential of P. spruceanum as source of antibacterial compounds that acts on important bacterial targets. These results contribute to the development of natural substances against pathogenic bacteria and to discovery of new antibiotics.
Anti–Zika virus activity and isolation of flavonoids from ethanol extracts of Curatella americana L. Leaves.
(2023) Lima, Lienne D’Auria; Reis, Adriana Cotta Cardoso; Sousa, Jordano Augusto Carvalho; Valente, Gabriel Mendonça; Silva, Breno de Mello; Magalhães, Cíntia Lopes de Brito; Kohlhoff, Markus; Teixeira, Luiz Fernando de Medeiros; Brandão, Geraldo Célio
The ethnomedicinal plant Curatella americana L. (Dilleniaceae) is a common shrub in the Brazilian Cerrado, whose ethanolic extract showed significant in vitro anti–Zika virus activity by the MTT colorimetric method. Currently, there is no drug in clinical use specifically for the treatment of this virus; therefore, in this work, the antiviral and cytotoxic properties of the ethanolic extract, fractions, and compounds were evaluated. The ethanolic extract of the leaves showed no cytotoxicity for the human MRC-5 cell and was moderately cytotoxic for the Vero cell (CC50 161.5 ± 2.01 μg/mL). This extract inhibited the Zika virus multiplication cycle with an EC50 of 85.2 ± 1.65 μg/mL. This extract was fractionated using the liquid–liquid partition technique, and the ethyl acetate fraction showed significant activity against the Zika virus with an EC50 of 40.7 ± 2.33 μg/mL. From the ethyl acetate fraction, the flavonoids quercetin-3-O-hexosylgallate (1), quercetin-3-O-glucoside (2), and quercetin (5) were isolated, and in addition to these compounds, a mixture of quercetin-3- O-rhamnoside (3) and quercetin-3-O-arabinoside (4) was also obtained. The isolated compounds quercetin and quercetin-3-O-hexosylgallate inhibited the viral cytopathic effect at an EC50 of 18.6 ± 2.8 and 152.8 ± 2.0, respectively. Additionally, analyses by liquid chromatography coupled to a mass spectrometer allowed the identification of another 24 minor phenolic constituents present in the ethanolic extract and in the ethyl acetate fraction of this species.
Anti–zika virus activity and isolation of flavonoids from ethanol extracts of Curatella americana L. leaves.
(2023) Lima, Lienne D’Auria; Reis, Adriana Cotta Cardoso; Sousa, Jordano Augusto Carvalho; Valente, Gabriel Mendonça; Silva, Breno de Mello; Magalhães, Cíntia Lopes de Brito; Kohlhoff, Markus; Teixeira, Luiz Fernando de Medeiros; Brandão, Geraldo Célio
The ethnomedicinal plant Curatella americana L. (Dilleniaceae) is a common shrub in the Brazilian Cerrado, whose ethanolic extract showed significant in vitro anti–Zika virus activity by the MTT colorimetric method. Currently, there is no drug in clinical use specifically for the treatment of this virus; therefore, in this work, the antiviral and cytotoxic properties of the ethanolic extract, fractions, and compounds were evaluated. The ethanolic extract of the leaves showed no cytotoxicity for the human MRC-5 cell and was moderately cytotoxic for the Vero cell (CC50 161.5 ± 2.01 μg/mL). This extract inhibited the Zika virus multiplication cycle with an EC50 of 85.2 ± 1.65 μg/mL. This extract was fractionated using the liquid–liquid partition technique, and the ethyl acetate fraction showed significant activity against the Zika virus with an EC50 of 40.7 ± 2.33 μg/mL. From the ethyl acetate fraction, the flavonoids quercetin-3-O-hexosylgallate (1), quercetin-3-O-glucoside (2), and quercetin (5) were isolated, and in addition to these compounds, a mixture of quercetin-3- O-rhamnoside (3) and quercetin-3-O-arabinoside (4) was also obtained. The isolated compounds quercetin and quercetin-3-O-hexosylgallate inhibited the viral cytopathic effect at an EC50 of 18.6 ± 2.8 and 152.8 ± 2.0, respectively. Additionally, analyses by liquid chromatography coupled to a mass spectrometer allowed the identification of another 24 minor phenolic constituents present in the ethanolic extract and in the ethyl acetate fraction of this species.
Bacterial vaginosis : prevalence, risk profile and association with sexually transmitted infections.
(2020) Teixeira, Pedro Moregola; Vital, Wendel Coura; Lima, Angélica Alves; Silva, Nayara Nascimento Toledo; Carneiro, Cláudia Martins; Teixeira, Luiz Fernando de Medeiros; Silva, Glenda Nicioli da
Background and Objectives: Bacterial vaginosis (BV) is the most common cause of vaginal discharge in the world. The study aimed to estimate the prevalence and to identify risk factors associated with bacterial vaginosis. Methods: A cross-sectional study was conducted in Ouro Preto, Brazil, between February and December 2017. Three hundred and forty-one women aged 18 years or older, users of the Brazilian Unified Health System, participated in this study. Women who used oral or topical antibiotics in the four weeks prior to the sample collection and women who had undergone a total hysterectomy were excluded from the study. After signing the Informed Consent Form and filling out a questionnaire containing sociodemographic, behavioral and sexual data, the participants were directed to the collection room, where the nurse collected the samples for the preventive examination of the cervix and also two vaginal swabs. Vaginal swabs and cervical samples were analyzed for cytological abnormalities and BV using Gram staining and cytology. Pathogens causing sexually transmitted infections (STIs) were identified by Polymerase Chain Reaction (PCR). For the analysis of the data, statistical package STATA version 10.0 was used. This study was approved by the Research Ethics Committee of the Federal University of Ouro Preto (UFOP). Results: During the study, 341 women were evaluated. The prevalence of BV using Gram staining (32.5% [CI95% 27.737.7%]) and cytology (27.7% [CI95% 23.032.8%]) was similar, however, the sensitivity of cytology was lower (77.8%). Risk factors associated with BV were smoking (IRR 1.5 [CI95%: 1.1 2.1]), use of an intrauterine device (IRR 2.8 [CI95%: 1.2 6.5]), and past medical history of BV (IRR 1.5 [CI95%: 1.1 2.1]). Correlation between the presence of BV and Trichomonas vaginalis (TV) infection (r=0.24) was observed. Conclusion: The prevalence of BV was affected by life habits and was prevalent in women with TV. Thus, behavioral and social prevention approaches to women with diverse risk profiles may help mitigate TV/BV prevalence and recurrence of BV.
Cell surface analysis of trypanosomes of the subgenus Schizotrypanum isolate from bats.
(1996) Pinto, Artur da Silveira; Teixeira, Luiz Fernando de Medeiros; Padron, Thais Cristina Baeta Soares Souto; Andrade, Arnaldo Feitosa Braga de
Two stocks (M5, M29) of trypanosomes of the subgenus Schizotrypanum were isolated from the bat Phylloslomus hastatus and analyzed for cell electrophoretic mobility (EPM) and lectin binding surface sites. Epimastigotes from the M5 and M29 stocks presented a mean EPM of around - 0.57 and -0.56 μm, s-1.V-1.cm, respectively. Differences in the agglutination profiles were detected between epimastigotes or trypomastigotes from the two parasite populations using lectins with specificity for D-GlcNAc, D-GalNAc, D-Gal and D-Man as probe. Major variation was observed between epimastigote forms. Additionally, the D-GlcNAc binding lectins WGA and BS II strongly interacted with the trypomastigote from both M5 and M29 stocks; this fact is evidence that these trypanosomes are distinct from Trypanosoma (Schizotrypanum) cruzi.
Chemical constituents, antioxidant potential, antibacterial study and photoprotective activity of Brazilian corn silk extract.
(2022) Azevedo, Amanda Scofield de; Seibert, Janaína Brandão; Amparo, Tatiane Roquete; Antunes, Amanda dos Santos; Sousa, Lucas Resende Dutra; Souza, Gustavo Henrique Bianco de; Teixeira, Luiz Fernando de Medeiros; Vieira, Paula Melo de Abreu; Santos, Viviane Martins Rebello dos; Nascimento, Adriana Mendes do; Nascimento, Andréa Mendes do
The aim of this work was to determine the total phenolic content and evaluate the antioxidant, antibacterial, photoprotective and cytotoxic properties of corn silk ethanol extract prepared from corn silk that was air-dried at room temperature. Corn silk ethanol extract has a high content of phenolic compounds. The concentrations of ethanol extract required to produce 50% of maximal effect (EC50) in DPPH and ABTS radical scavenging assays were 489.0 and 166.1 μg/mL respectively, indicating low activity when compared to the positive control. The ethanolic extract of corn silk showed antibacterial activity, mainly on Gram-positive bacteria. The in vitro sun protection factor (SPF) of the ethanolic extract of corn silk incorporated into sunscreen UVA-UVB 5% gel with Pemulen TR-1® was evaluated for the first time. A relative increase in SPF efficacy was observed for the extract when the sunscreen was incorporated. The ethanolic extract of corn silk and the gel were considered non-cytotoxic. The corn silk ethanolic extract was characterized using ultra performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry (UPLC-QTOF-MS/MS). Eleven compounds including flavonoids, coumaric acid derivatives, terpenoid, hydroxycinnamic acid derivative and quinic acid derivative were suggested based on their accurate mass and MS/MS spectra.
Development of propolis nanoemulsion with antioxidant and antimicrobial activity for use as a potential natural preservative.
(2019) Seibert, Janaína Brandão; Silva, Jessica Paola Bautista; Amparo, Tatiane Roquete; Petit, Alicia; Pervier, Pauline; Almeida, Juliana Cristina dos Santos; Azevedo, Mariana Costa; Silveira, Benila Maria; Brandão, Geraldo Célio; Souza, Gustavo Henrique Bianco de; Teixeira, Luiz Fernando de Medeiros; Santos, Orlando David Henrique dos
Propolis has demonstrated potential use as food preservative but it presents strong and unpleasant flavor that alters the sensory characteristics foods. A nanoemulsion was proposed to carry the Brazilian propolis extracts for use as natural food preservative. Antimicrobial and antioxidant activities and chemical constituents of the extracts were investigated. The latter were made by sequential extraction using different solvents (hexane, ethyl acetate and ethanol). Antimicrobial activity was evaluated by agar diffusion and microdilution methods and antioxidant activity by DPPH and ABTS assays. Extracts showed antibacterial and antioxidant activity, highlighting the ethanolic which contained artepillin-C, kaempferide, drupanin and p-coumaric acid as main compounds by LC-MS analysis. The nanoemulsion developed by phase inversion method was characterized and stable under thermal-stress and centrifugation conditions. Biological properties evaluated were effectively maintained by the formulation. It was concluded that the nanoemulsion can be used as a food preservative, preventing degradation and masking the propolis off-flavor.
Estudo fitoquímico e atividades biólogicas de extratos etanólicos especiés Nectandra nitidula, Curatella americana e Albizia niopoides.
(2019) Lima, Lienne D’Auria; Brandão, Geraldo Célio; Teixeira, Luiz Fernando de Medeiros; Magalhães, José Carlos de; Santos, Orlando David Henrique dos; Brandão, Geraldo Célio
Foi realizada uma triagem fitoquímica preliminar de extratos das espécies Curatella americana, Nectandra nitidula e Albizia niopoides ocorrentes no estado de Minas Gerais. Os extratos foram preparados via percolação exaustiva a frio com etanol (92,8o GL), os principais metabólitos secundários foram identificados por cromatografia em camada delgada comparando-se com amostras de referência, e pela técnica de cromatografia líquida de ultra eficiência acoplada a ultravioleta, espectrometria de massa (CLUE-UV-EM) e espectrometria de massa sequencial (EMEM). Os principais constituintes identificados foram flavonoides da classe flavonol para a espécie Curatella americana e alcaloides da espermidina para a espécie Albizia niopoides. O extrato de folhas de C. americana foi submetido a um fracionamento por partição líquido-líquido, utilizando solventes de polaridade crescente. A fração em acetato de etila foi refracionada por cromatografia de exclusão molecular utilizando resina de Sephadex LH-20, e por cromatografia em coluna de sílica gel de fase reversa ligada a octadecilsilano (C18), e obteve dois sólidos isolados denominados CAFAE-1 e CAFAE-2. Neste trabalho foram realizados ensaios que permitiram a avaliação da atividade citotóxica, anti-Zika vírus, antibacteriana e anti-Trypanosoma cruzi dos diferentes extratos. O extrato de folhas de C. Americana mostrou-se moderamente citotóxico, mas com atividade significativa contra o Zika vírus, com CE50 de 85,23 μg/mL (IS = 2,56). Adicionalmente, a fração acetato de etila também apresentou forte atividade contra o Zika vírus com CE50 de 40,72 μg/mL (IS = 1,38), enquanto que somente a CAFAE-1 mostrou atividade contra o Zika vírus com CE50 de 152,8 μg/mL (IS = 2,0). A espécie N. nitidula revelou-se moderadamente citotóxica e foi ativa contra o Zika vírus com CE50 104,2 μg/mL (IS = 1,38), além disso, apresentou atividade antibacteriana contra Staphylococcus spp. O extrato de caules da espécie A. niopoides mostrou-se moderamente citotóxico para linhagens de células Vero e MRC-5 com CC50 de 62,22 e 30,54 μg/mL, respectivamente. Adicionalmente, este extrato apresentou uma atividade antibacteriana significativa contra a maioria das bactérias Gram-positivas e negativas testadas. Já o extrato de folhas dessa espécie demonstrou ausência de citotoxicidade e foi o mais ativo contra as formas amastigotas de T. cruzi, demonstrando 85% de inibição desses parasitos (IS = 2,65). Portanto, conclui-se que os constituintes de média polaridade podem ser os responsáveis pela atividade anti-Zika vírus observada e que os alcaloides da espermidina podem ser os responsáveis pelas atividades biológicas observadas para a espécie Albizia niopoides.
Evaluation of anti-candida albicans activity and release of ketoconazole in PMMA-G-PEG 4000 films.
(2022) Reynaldo, Juliana Ribeiro; Novack, Kátia Monteiro; Sousa, Lucas Resende Dutra; Vieira, Paula Melo de Abreu; Amparo, Tatiane Roquete; Souza, Gustavo Henrique Bianco de; Teixeira, Luiz Fernando de Medeiros; Barboza, Ana Paula Moreira; Neves, Bernardo Ruegger Almeida; Alvarenga, Meiry Edivirges; Martins, Felipe Terra; Santos, Viviane Martins Rebello dos
Modified release systems depend on the selection of an appropriate agent capable of controlling the release of the drug, sustaining the therapeutic action over time, and/or releasing the drug at the level of a particular tissue or target organ. Polyethylene glycol 4000 (PEG 4000) is commonly employed in drug release formulations while polymethyl methacrylate (PMMA) is non-toxic and has a good solubility in organic solvents. This study aimed at the incorporation of ketoconazole in PMMA-g-PEG 4000 and its derivatives, thus evaluating its release profile and anti-Candida albicans and cytotoxic activities. Ketoconazole was characterized and incorporated into the copolymers. The ketoconazole incorporated in the copolymer and its derivatives showed an immediate release profile. All copolymers with ketoconazole showed activity against Candida albicans and were non-toxic to human cells in the entire concentration tested.
Fatores de risco e polimorfismos dos genes ECA E GNB3 associados à hipertensão no município de Ouro Preto, MG.
(2022) Agostini, Lívia da Cunha; Silva, Glenda Nicioli da; Teixeira, Luiz Fernando de Medeiros; Silva, Glenda Nicioli da; Isoldi, Mauro César; Ribeiro, Daniel Araki
A Hipertensão arterial (HA) é uma doença crônica caracterizada por pressão arterial sistólica igual ou superior a 140mmHg e/ou pressão arterial diastólica igual ou superior a 90mmHg. A HA é um fator de risco considerável para doenças como aterosclerose e trombose, acometendo principalmente o sistema cardíaco, cerebral, renal e vascular periférico. As complicações clínicas decorrentes, bem como a frequência elevada em nossa população, fazem com que a HA tenha um importante papel nos programas de saúde pública. Dentre os fatores responsáveis pelo desencadeamento da HA encontram-se alterações genéticas, envolvendo vários genes e suas variantes. Dessa maneira, estudos clínicos, epidemiológicos e genéticos têm sido realizados para melhor compreender os mecanismos envolvidos na HA, com a finalidade de melhorar o diagnóstico e contribuir para a prevenção desta doença. Os objetivos do presente projeto foram identificar os fatores de risco, os parâmetros bioquímicos e os diferentes polimorfismos genéticos (genes da Enzima Conversora de Angiotensina - ECA e Subunidade Beta 3 da Proteína G - GNB3) associados à hipertensão arterial na população de Ouro Preto/MG. Os polimorfismos dos genes GNB3 (rs5443) e ECA (rs4291/rs4363 e rs4335) foram feitas por q- PCR, usando o sistema TaqMan®. Os exames de triglicérides, colesterol total, HDL-colesterol, LDL-colesterol, não-HDL colesterol, VLDL, ureia, creatinina, glicose e ácido úrico foram feitos por espectrofotometria UV/Vis com a utilização dos reagentes da Cobas® Substratos (Roche) e processadas no equipamento COBAS INTEGRA® 400 Plus (Roche). As dosagens dos íons sódio e potássio foram realizadas por eletrodo íon seletivo (Roche) e processadas no equipamento AVL 9180. Os resultados mostraram que a hipertensão arterial esteve associada à idade, nível de escolaridade, renda familiar, tabagismo, obesidade, triglicérides, VLDL, ureia, creatinina, glicose, ácido úrico e sódio. Influências das variantes genéticas da ECA e GNB3 sobre a hipertensão arterial não foram observadas, mas estiveram associadas com o triglicérides, colesterol total, HDL-colesterol, LDL-colesterol, não-HDL colesterol, VLDL, ureia, glicose e ácido úrico. Em conclusão, a HA foi associada à condição socioeconômica, hábitos de vida e alteração de parâmetros bioquímicos. Apesar dos polimorfismos estudados não estarem associados à HA, eles podem estar associados à desregulação de outros parâmetros bioquímicos, mostrando a importância de se avaliar geneticamente indivíduos de familiares com HA, a fim de prevenir as causas e consequências dessa doença.
Herbal medicines to the treatment of skin and soft tissue infections : advantages of the multi‐targets action.
(2019) Amparo, Tatiane Roquete; Seibert, Janaína Brandão; Vieira, Paula Melo de Abreu; Teixeira, Luiz Fernando de Medeiros; Santos, Orlando David Henrique dos; Souza, Gustavo Henrique Bianco de
The research for new treatments of skin and soft tissue infections (SSTIs) is important due to their high prevalence and number of hospitalizations. The purpose of this review is to address the pathophysiology of SSTIs to highlight the advantages of herbal medicines to their treatment, showing examples of species and compounds with multi‐targets action. SSTIs have a complex physiopathology involving the microorganism, as well as inflammation and difficult healing. Therefore, antimicrobial, anti‐inflammatory, antioxidant and healing activities are an approach possible for their treatment. Herbal medicines have a wide diversity of biological compounds, mainly phenolic compounds that may act on different targets and also have synergism between them. Therefore, a single medicine may have the four key activities that allied allow eliminating the infection, control the inflammation process and accelerating the healing process, preventing complications with chronic infections.
Incidência de tuberculose pulmonar na população indígena Xakriabá, Minas Gerais.
(2019) Marinho, Carolina Coimbra; Sales, Maria Lilian; Pereira, Rodrigo Pastor Alves; Ribeiro, Simone Rodrigues; Moreira, Anderson Davi; Costa, André Tetzl; Silva, Jaime Costa da; Teixeira, Luiz Fernando de Medeiros; Ribeiro, Gustavo Meirelles; Coelho, George Luiz Lins Machado
Introdução: a população indígena brasileira permanece vulnerável à tuberculose pulmonar (TB). Objetivo: relatar a incidência de (TB) na população indígena Xakriabá (N=7.046) residente em Minas Gerais, Brasil, em 2011. Métodos: sintomáticos respiratórios foram identificados através de busca ativa por agentes comunitários de saúde indígena treinados. A TB foi investigada pelo exame clínico, baciloscopia e cultura de amostras de escarro dos sujeitos sintomáticos. A identificação de espécies pela sonda PRAhsp65 e o teste de sensibilidade a quimioterápicos foram realizados nas amostras positivas. Resultados: amostras de escarro de 273 de 315 sintomáticos respiratórios foram examinadas. 176 pessoas (70 homens, 10 a 86 anos) foram examinadas. Uma amostra teve baciloscopia positiva e quatro foram positivas para Mycobacterium tuberculosis em cultura (incidência: 56,8/100mil hab). Conclusões: a incidência de TB na população Xakriabá (56,8/100mil hab) é maior que a da população geral no Brasil.
Melaleuca leucadendra essential oil promotes loss of cell membrane and wall integrity and inhibits bacterial growth : an in silico and in vitro approach.
(2020) Silva, Jessica Paola Bautista; Seibert, Janaína Brandão; Amparo, Tatiane Roquete; Rodrigues, Ivanildes Vasconcelos; Teixeira, Luiz Fernando de Medeiros; Souza, Gustavo Henrique Bianco de; Santos, Orlando David Henrique dos
Essential oils are potential antimicrobial agents and can be used as active ingredients in the pharmaceutical, food and cosmetics industries. This work intends to evaluate the antibacterial activity and design a strategy for the proposition of the mechanism of action of Melaleuca leucadendra essential oil. Optimum concentration of the bacteria and the phase where they had the highest pathogenic activity were determined. Results show that for each microorganism it is necessary to use a diferent concentration at the time of adjusting the initial inoculum, and that the time to achieve exponential growth phase varies from one to the other. M. leucadendra essential oil demonstrated in vitro antimicrobial properties. This oil was chemically characterized and the main compounds were evaluated by their mechanism of antibacterial action based on structure–activity analysis. The mechanism is related to the increase of bacteria cell membrane permeability. This indication was confrmed by fow cytometry and transmission electronic microscopy. Thus, in silico analysis is an important tool in the search for new antimicrobial agents and these results showed that M. leucadendra essential oil may be useful on the development of new chemotherapies or food preservation systems.
Métodos para avaliação in vitro da atividade antimicrobiana de plantas medicinais : a necessidade da padronização.
(2018) Amparo, Tatiane Roquete; Braga, Vanessa Cristina de Carvalho; Seibert, Janaína Brandão; Souza, Gustavo Henrique Bianco de; Teixeira, Luiz Fernando de Medeiros
A crescente incidência de patógenos resistentes aos medicamentos atuais incentiva a busca de novos agentes antimicrobianos. Neste contexto, as plantas medicinais se destacam, sendo uma importante fonte de novos fármacos. Existem diversos métodos para avaliar a atividade antibacteriana e antifúngica de extratos, frações, óleos essenciais e substâncias isoladas de vegetais. Os mais conhecidos incluem métodos de difusão, diluição e bioautografia. A proposta desse trabalho é apresentar os métodos mais utilizados atualmente, juntamente com suas vantagens, desvantagens e fatores interferentes. Entre os artigos indexados na biblioteca SciELO, abrangendo os últimos dez anos, somente 4,4% das pesquisas com plantas medicinais estão relacionadas com atividade antimicrobiana. O método mais utilizado foi a microdiluição (57,9%), o mais recomendado devido à alta sensibilidade, à quantidade mínima de reagentes e amostra e à possibilidade de um maior número de réplicas. Nos trabalhos que utilizaram esse método, foram verificadas divergências de fatores que podem interferir nos resultados. A fim de facilitar a obtenção de resultados comparáveis e reprodutíveis, destaca-se a necessidade da padronização dos métodos utilizadas pelos pesquisadores. Recomenda-se utilizar como referência as normas estabelecidas pelo CLSI para meio de cultura e concentração de inóculo nos testes. Além disso, também recomenda-se a inclusão de um controle negativo da forma de solubilização das amostras, com quantificação do crescimento microbiano, para evitar a interferência nos resultados.
Nanostructured systems improve the antimicrobial potential of the essential oil from cymbopogon densiflorus leaves.
(2019) Seibert, Janaína Brandão; Rosa, Juliana dos Santos; Almeida, Tamires Cunha; Amparo, Tatiane Roquete; Rodrigues, Ivanildes Vasconcelos; Lanza, Juliane Sousa; Frezard, Frederic Jean Georges; Soares, Rodrigo Dian de Oliveira Aguiar; Teixeira, Luiz Fernando de Medeiros; Souza, Gustavo Henrique Bianco de; Vieira, Paula Melo de Abreu; Barichello, José Mario; Santos, Orlando David Henrique dos
The physicochemical characteristics of nanostructured suspensions are important prerequisites for the success of new drug development. This work aimed to develop nanometric systems containing Cymbopogon densiflorus leaf essential oil and to evaluate their antimicrobial activity. The essential oil was isolated by hydrodistillation from leaves and analyzed by GC-MS. The main constituents were found to be trans-p-mentha-2,8-dien-1-ol, cis-p-mentha2,8-dien-1-ol, trans-p-mentha-1(7),8-dien-2-ol, cis-piperitol, and cis-p-mentha-1(7),8-dien-2-ol. In silico prediction analysis suggested that this oil possesses antimicrobial potential and the main mechanism of action might be the peptidoglycan glycosyltransferase inhibition. Nanoemulsions were prepared by the phase inversion method, and liposomes were made by the film hydration method. Qualitative evaluation of the antimicrobial activity was performed by the diffusion disk assay with 24 microorganisms; all of them were found to be sensitive to the essential oil. Subsequently, this property was quantified by the serial microdilution technique, where the nanoformulations demonstrated improved activity in comparison with the free oil. Bactericidal action was tested by the propidium iodide method, which revealed that free essential oil and nanoemulsion increased cytoplasmic membrane permeability, while no difference was observed between negative control and liposome. These results were confirmed by images obtained using transmission electron microscopy. This study has shown an optimization in the antimicrobial activity of C. densiflorus essential oil by a nanoemulsion and a liposomal formulation of the active substances.
New studies in vitro antibacterial evaluation and cell viability in PMMA-G-PEG 4000 derivatives with encapsulated Erythromycin.
(2022) Azevedo, Maria Luíza Schaefer; Rezende, Giselle A. S.; Sousa, Lucas Resende Dutra; Reis, Rúbia Castro Fernandes Melo; Novack, Kátia Monteiro; Barboza, Ana Paula Moreira; Neves, Bernardo Ruegger Almeida; Amparo, Tatiane Roquete; Teixeira, Luiz Fernando de Medeiros; Vieira, Paula Melo de Abreu; Perasoli, Fernanda Barçante; Santos, Viviane Martins Rebello dos
Synthetic polymers have been extensively studied in several areas of knowledge, one of which is the pharmaceutical. The drug when encapsultated into the PMMA-g-PEG 4000 matrix can produce fewer side effects. The most frequent side effects of erythromycin are gastrointestinal and are dose related. Nausea, vomiting and diarrhea occur in low frequency with the usual oral doses. The drug used in this study was Erythromycin, an antimicrobial that acts directly on bacterial protein synthesis. Erythromycin was encapsulated into PMMA-g-PEG 4000 derivatives. All copolymers afther encapsultaions were characterized and identified by atomic force microscopy (AFM). In vitro assays of release, antimicrobial activity and cytotoxicity were performed for the copolymers obtained. The copolymers PMMA-g-PEG 4000 HAL and PMMA-g-PEG 4000 ACET showed drug controlled release profiles. All PMMA-g-PEG 4000 derivatives showed antibacterial activity against Staphylococcus aureus and did not show a cytotoxic effect on human fibroblasts.