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1.
Artigo em Inglês | MEDLINE | ID: mdl-38619589

RESUMO

To evaluate the antibacterial, antibiofilm and antivirulence potential of the main diterpenes from Copaifera spp. oleoresins against multidrug-resistant (MDR) bacteria. Antimicrobial assays included determination of the Minimum Inhibitory Concentration (MIC), Minimum Bactericidal Concentration (MBC), Minimum Inhibitory Concentration of Biofilm (MICB50), as well as synergistic and antivirulence assays for eight diterpenes against MDR. The tests revealed that two diterpenes (named 1 and 5) showed the best results, with MIC and MBC between 12.5 and 50 µg/mL against most MDR bacteria. These diterpenes exhibited promising MICB50 in concentration between 3.12-25 µg/mL but showed no synergistic antimicrobial activity. In the assessment of antivirulence activity, diterpenes 1 and 5 inhibited only one of the virulence factors evaluated (Dnase) produced by some strains of S. aureus at subinhibitory concentration (6.25 µg/mL). Results obtained indicated that diterpenes isolated from Copaifera oleoresin plays an important part in the search of new antibacterial and antibiofilm agents that can act against MDR bacteria.

2.
Sci Rep ; 13(1): 21079, 2023 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-38030663

RESUMO

Normal-to-cancer (NTC) transition is known to be closely associated to cell´s biomechanical properties which are dependent on the dynamics of the intracellular medium. This study probes different human cancer cells (breast, prostate and lung), concomitantly to their healthy counterparts, aiming at characterising the dynamical profile of water in distinct cellular locations, for each type of cell, and how it changes between normal and cancer states. An increased plasticity of the cytomatrix is observed upon normal-to-malignant transformation, the lung carcinoma cells displaying the highest flexibility followed by prostate and breast cancers. Also, lung cells show a distinct behaviour relative to breast and prostate, with a higher influence from hydration water motions and localised fast rotations upon NTC transformation. Quasielastic neutron scattering techniques allowed to accurately distinguish the different dynamical processes taking place within these highly heterogeneous cellular systems. The results thus obtained suggest that intracellular water dynamics may be regarded as a specific reporter of the cellular conditions-either healthy or malignant.


Assuntos
Neoplasias , Água , Humanos , Difração de Nêutrons , Nêutrons
3.
Ecotoxicol Environ Saf ; 264: 115398, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37634482

RESUMO

Pesticide exposure is an important driver of bee declines. Laboratory toxicity tests provide baseline information on the potential effects of pesticides on bees, but current risk assessment schemes rely on one species, the highly social honey bee, Apis mellifera, and there is uncertainty regarding the extent to which this species is a suitable surrogate for other pollinators. For this reason, Osmia cornuta and Osmia bicornis have been proposed as model solitary bee species in the EU risk assessment scheme. The use of solitary bees in risk assessment requires the development of new methodologies adjusted to the biology of these species. For example, oral dosing methods used with honey bees cannot be readily applied to solitary bees due to differences in feeding behaviour and social interactions. In this study, we describe the "petal method", a laboratory feeding method, and validate its use in acute and chronic exposure oral tests with Osmia spp. We conducted five experiments in which we compared the performance of several artificial flowers combining visual and olfactory cues against the petal method, or in which variations of the petal method were confronted. We then use the results of these experiments to optimize the feeding arenas and propose standardized methods for both acute and chronic exposure tests. The petal method provides high levels of feeding success, thus reducing the number of bees needed. It works with a wide variety of petal species and with both female and male Osmia spp., thus ensuring reproducibility across studies. To validate the use of the petal method in ecotoxicology tests, we assess the toxicity of a standard reference insecticide, dimethoate, in O. cornuta adults and determine LD50 values for this species. The petal method should facilitate the inclusion of solitary bees in risk assessment schemes therefore increasing the protection coverage of pesticide regulation.


Assuntos
Inseticidas , Praguicidas , Masculino , Abelhas , Feminino , Animais , Praguicidas/toxicidade , Reprodutibilidade dos Testes , Inseticidas/toxicidade , Flores , Testes de Toxicidade
4.
Artigo em Inglês | MEDLINE | ID: mdl-37476654

RESUMO

Background: Mortality rates in patients with haematological malignancies who required intensive care unit (ICU) admission have in the past been high. More recently, however, improved outcomes for critically ill haematological patients have been reported. Objectives: To determine outcomes, average length of ICU stay, and factors associated with mortality in patients with haematological malignancies and neutropenic fever in the multidisciplinary ICU (MICU) at Universitas Academic Hospital (UAH), Bloemfontein, Free State Province, South Africa. Methods: We conducted a retrospective review of medical and laboratory records of all patients admitted to the UAH MICU with haematological malignancies and febrile neutropenia between 2010 and 2019. Results: A total of 182 patients with haematological malignancies were admitted to the MICU between 1 January 2010 and 31 December 2019, of whom 51 (28.0%) fulfilled the inclusion criteria for the study. The median age was 33 years, and 29 patients (56.9%) were female. Most patients had either acute myeloid leukaemia (n=22; 43.1%) or acute lymphocytic leukaemia (n=16; 31.4%), while B-cell lymphoma (n=12; 23.5%) and multiple myeloma (n=1; 2%) were less frequent. The median length of stay in the ICU was 3 days. ICU mortality was 76.5% and hospital mortality 82.4%. Factors associated with mortality included septic shock, vasoactive agent use and mechanical ventilation. Conclusion: Patients with haematological malignancies and febrile neutropenia in the UAH MICU have high ICU and hospital mortality rates. More needs to be done with regard to timeous management of patients with haematological malignancies and septic shock in our setting to improve survival. Study synopsis: This is the first study to report on ICU mortality of adult patients with haematological malignancies and neutropenic sepsis in a tertiary hospital ICU in the Free State. These patients had a high mortality rate. What the study adds. Our study shows that septic shock, vasoactive agent use and mechanical ventilation were associated with increased ICU mortality.Implications of the findings. Strict adherence to infection prevention and control measures in haematology wards is required. Early recognition and treatment of sepsis before it progresses to septic shock is important. ICUs must be designed so that isolation cubicles are readily available to prevent cross-infection of patients.

5.
Phys Chem Chem Phys ; 24(25): 15406-15415, 2022 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-35704895

RESUMO

Normal-to-malignant transformation is a poorly understood process associated with cellular biomechanical properties. These are strongly dependent on the dynamical behaviour of water, known to play a fundamental role in normal cellular activity and in the maintenance of the three-dimensional architecture of the tissue and the functional state of biopolymers. In this study, quasi-elastic neutron scattering was used to probe the dynamical behaviour of water in human cancer specimens and their respective surrounding normal tissue from breast and tongue, as an innovative approach for identifying particular features of malignancy. This methodology has been successfully used by the authors in human cells and was the first study of human tissues by neutron scattering techniques. A larger flexibility was observed for breast versus tongue tissues. Additionally, different dynamics were found for malignant and non-malignant specimens, depending on the tissue: higher plasticity for breast invasive cancer versus the normal, and an opposite effect for tongue. The data were interpreted in the light of two different water populations within the samples: one displaying bulk-like dynamics (extracellular and intracellular/cytoplasmic) and another with constrained flexibility (extracellular/interstitial and intracellular/hydration layers).


Assuntos
Neoplasias , Água , Humanos , Difração de Nêutrons/métodos , Nêutrons
6.
J Endocrinol Invest ; 45(5): 999-1009, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34988938

RESUMO

PURPOSE: Cushing's disease is associated with significant morbidity; thus, additional tumor-directed drugs with the potential to exert antineoplastic effects on corticotroph adenoma cells are desired. The phosphoinositide-3-kinase (PI3K)/protein kinase B (AKT) pathway, which plays regulatory role in cell survival and proliferation, is activated in pituitary adenomas. The present study evaluated the effects of BKM120 (Buparlisib), an oral PI3K inhibitor, on cell viability, apoptosis, cell cycle phase distribution, and ACTH production in mouse corticotroph tumor cells. METHODS: AtT-20/D16v-F2 mouse pituitary corticotroph tumor cells were treated with increasing concentrations of BKM120 or vehicle. Cell viability was measured using an MTS-based assay. Apoptosis was evaluated by Annexin V staining. Cell cycle analysis was performed by propidium iodide DNA staining and flow cytometry. Gene expression of cell cycle regulators (Cdkn1b, Ccnd1, Ccne1, Cdk2, Cdk4, Myc, and Rb1) was assessed by qPCR. Protein expression of p27, total and phosphorylated Akt was assessed by Western blot. ACTH levels were measured in the culture supernatants by chemiluminescent immunometric assay. RESULTS: Treatment with BKM120 decreased AtT-20/D16v-F2 cell viability, induced a G0/G1 cell cycle arrest, reduced the phosphorylation of Akt at Serine 473, and increased p27 expression. Furthermore, BKM120 treatment diminished ACTH levels in the cell culture supernatants. CONCLUSION: In vitro inhibition of PI3K/AKT pathway by BKM120 resulted in anti-proliferative effects on corticotroph tumor cells, decreasing cell viability and ACTH production. These encouraging findings shape the path for further experiments with the inhibition of PI3K/AKT pathway in Cushing's disease.


Assuntos
Adenoma , Hipersecreção Hipofisária de ACTH , Neoplasias Hipofisárias , Adenoma/patologia , Hormônio Adrenocorticotrópico/metabolismo , Aminopiridinas , Animais , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Corticotrofos/metabolismo , Corticotrofos/patologia , Humanos , Camundongos , Morfolinas , Fosfatidilinositol 3-Quinase/metabolismo , Fosfatidilinositol 3-Quinase/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Hipersecreção Hipofisária de ACTH/metabolismo , Neoplasias Hipofisárias/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo
7.
Arq. bras. med. vet. zootec. (Online) ; 73(6): 1260-1268, Nov.-Dec. 2021. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1355671

RESUMO

The use of blood metabolites (BM), fecal starch (FS), and apparent digestion of starch, (ATTSD) as indicators of feed efficiency (FE) in beef cattle in the feedlot was studied. Fourteen bulls were used, originating in an industrial cross, without a defined racial group, with mean body weight of 284.86kg, individually fed, being evaluated in a 42-day confinement system. After the evaluation, the animals were divided into two groups according to the individual FE: high feed efficiency (HE) and low feed efficiency (LE). There was a difference between the groups in the variables FE, feed conversion (FC), final weight (FW), and daily weight gain (DWG). The FE had a positive correlation with DWG, FC, and FW. There was no difference between the groups for the variables BM, FS, and ATTSD, nor was there any correlation between these variables and FE. Considering the feed cost, the HE animals proved more profitable. BM, FS, and ATTSD did not statistically show potential to be used as indicators of FE, despite the evidence of numerical differences of these variables between the different groups, tendency of correlations with FE, and discriminating function with potential assertiveness.(AU)


Foi estudada a utilização dos metabólitos sanguíneos (BM), do amido fecal (FS) e da digestão aparente do amido (ATTSD) como indicadores de eficiência alimentar (FE) em bovinos de corte em confinamento. Utilizaram-se 14 touros, originários de cruzamento industrial, sem grupo racial definido, peso corporal médio de 284,86kg, alimentados individualmente, sendo avaliados em sistema de confinamento por 42 dias. Após a avaliação, dividiram-se os animais em dois grupos, de acordo com a FE individual: alta eficiência alimentar (HE) e baixa eficiência alimentar (LE). Houve diferença entre os grupos nas variáveis FE, conversão alimentar (FC), peso final (FW) e ganho de peso diário (DWG). A FE teve correlação positiva com DWG, FC e FW. Não houve diferença entre os grupos para as variáveis BM, FS e ATTSD, tampouco houve correlação entre essas variáveis e a FE. Considerando-se o custo alimentar, os animais HE mostraram-se mais lucrativos. BM, FS e ATTSD não mostraram, estatisticamente, potencial para serem utilizados como indicadores de FE, apesar da evidência de diferenças numéricas dessas variáveis entre os diferentes grupos, tendência de correlações com a FE e de função discriminante com potencial assertividade.(AU)


Assuntos
Animais , Bovinos , Aumento de Peso , Gado/sangue , Fenômenos Fisiológicos da Nutrição Animal , Peso Corporal , Custos e Análise de Custo
8.
Braz. j. biol ; 81(3): 728-736, July-Sept. 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1153401

RESUMO

Abstract Xylella fastidiosa is a plant-pathogenic bacterium that lives inside host xylem vessels, where it forms biofilm which is believed to be responsible for disrupting the passage of water and nutrients. Pectobacterium carotovorum is a Gram-negative plant-specific bacterium that causes not only soft rot in various plant hosts, but also blackleg in potato by plant cell wall degradation. Chagas disease, which is caused by Trypanosoma cruzi, has been commonly treated with nifurtimox and benzonidazole, two drugs that cause several side effects. As a result, the use of natural products for treating bacterial and neglected diseases has increased in recent years and plants have become a promising alternative to developing new medicines. Therefore, this study aimed to determine, for the first time, the chemical composition of essential oil from Psidium guajava flowers (PG-EO) and to evaluate its in vitro anti-Xylella fastidiosa, anti-Pectobacterium carotovorum, anti-Trypanosoma cruzi and cytotoxic activities. PG-EO was obtained by hydrodistillation in a Clevenger apparatus while its chemical composition was determined by gas chromatography-flame ionization detection (GC-FID) and gas chromatography-mass spectrometry (GC-MS). Major compounds identified in PG-EO were α-cadinol (37.8%), β-caryophyllene (12.2%), nerolidol (9.1%), α-selinene (8.8%), β-selinene (7.4%) and caryophyllene oxide (7.2%). Results showed that the PG-EO had strong trypanocidal activity against the trypomastigote forms of Trypanosoma cruzi (IC50 = 14.6 μg/mL), promising antibacterial activity against X. fastidiosa (MIC = 12.5 μg/mL) and P. carotovorum (MIC = 62.5 μg/mL), and moderate cytotoxicity against LLCMK2 adherent epithelial cells in the concentration range (CC50 = 250.5 μg/mL). In short, the PG-EO can be considered a new source of bioactive compounds for the development of pesticides and trypanocide drugs.


Resumo Xylella fastidiosa é uma bactéria patogênica que vive dentro dos vasos do xilema hospedeiro, onde forma um biofilme responsável por interromper a passagem de água e nutrientes. Pectobacterium carotovorum é uma bactéria Gram-negativa que causa não só podridão macia em várias plantas hospedeiras, mas também canela-preta na batata por degradação da parede celular da planta. A doença de Chagas, causada pelo Trypanosoma cruzi, é comumente tratada com nifurtimox e benzonidazol, duas drogas que causam vários efeitos colaterais. Como resultado, o uso de produtos naturais para o tratamento de doenças bacterianas e negligenciadas aumentou nos últimos anos e as plantas continuam sendo uma alternativa promissora para o desenvolvimento de novos medicamentos. Portanto, este estudo teve como objetivo determinar, pela primeira vez, a composição química do óleo essencial de flores de Psidium guajava (PG-EO) e avaliar suas propriedades anti-Xylella fastidiosa, anti-Pectobacterium carotovorum, anti-Trypanosoma cruzi e citotóxica in vitro. PG-EO foi obtido por hidrodestilação em um aparelho Clevenger, enquanto sua composição química foi determinada por cromatografia em fase gasosa com detecção por ionização por chama (CG-DIC) e por cromatografia em fase gasosa acoplada à espectrometria de massa (CG-EM). Os principais compostos identificados no PG-EO foram α-cadinol (37,8%), β-cariofileno (12,2%), nerolidol (9,1%), α-selineno (8,8%), β-selineno (7,4%) e óxido de cariofileno (7,2%). Os resultados mostraram que o PG-EO apresentou forte atividade tripanocida contra as formas tripomastigotas de T. cruzi (CI50 = 14,6 μg/mL), promissora atividade antibacteriana contra X. fastidiosa (MIC = 12,5 μg/mL) e P. carotovorum (MIC = 62,5 μg/mL) e citotoxicidade moderada contra células epiteliais aderentes (LLCMK2) na faixa de concentração (CC50 = 250,5 μg/mL). Em suma, o PG-EO pode ser considerado uma nova fonte de compostos bioativos para o desenvolvimento de pesticidas e drogas tripanocidas.


Assuntos
Óleos Voláteis/farmacologia , Myrtaceae , Psidium , Testes de Sensibilidade Microbiana , Folhas de Planta , Flores , Xylella
9.
Med Oral Patol Oral Cir Bucal ; 26(5): e632-e641, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34415001

RESUMO

BACKGROUND: To assess the effectiveness of preemptive analgesia in dental implant surgery in randomized controlled trials (RCTs). MATERIAL AND METHODS: The present study was conducted in accordance with the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement and registered in PROSPERO database CRD42020168757. A search without restrictions regarding language or date of publication was conducted in six databases and gray literature. A random effect meta-analysis compared the efficacy of preemptive analgesia compared to placebo through pooled OR and 95%CI. The interpretation of results followed the certainty of evidence using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach together with the magnitude of the effect according to GRADE guidelines. RESULTS: Four studies were included in the review and three were incorporated into the meta-analysis. All studies demonstrated that preemptive analgesia contributed to a significant improvement in the postoperative pain control. However, the overall pooled standard mean difference (SMD) showed that preemptive analgesia had small effects compared to placebo in reducing pain (SMD: -0.45; IC: -0.83; -0.08) with low certainty of the evidence. Our meta-analysis showed that the magnitude of the effect was bigger six to eight hours after the surgery (large effect), compared to the time of one to two hours after the surgery (small effect). CONCLUSIONS: Preemptive analgesia may have a positive effect in reducing pain compared to not using preemptive medication, but the evidence is very uncertain.


Assuntos
Analgesia , Implantes Dentários , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
10.
Biotechnol Lett ; 43(7): 1487-1502, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33822305

RESUMO

The interest in bioactive compounds from microalgae is increasing since they have medicinal and nutritional areas. The present work aims to evaluate the potential pharmaceutical interest of extracts from three eustigmatophyte strains from the Coimbra Collection of Algae (ACOI): Chlorobotrys gloeothece, Chlorobotrys regularis and Characiopsis aquilonaris. Antioxidant and antiproliferative activities were determined as well as chlorophyll a, carotenoid and phenolic total contents. In addition, major pigments and sterols were identified and quantified. The three strains were grown until the stationary phase and then the biomass was extracted. Antioxidant activity was measured by TEAC, DPPH and FRAP assays and antiproliferative effect was assessed by the MTT method on MCF-7, PC-3 and NHDF cells. The pigment and phenolic total contents were determined by spectrophotometry. Of these strains, C. aquilonaris showed the highest antioxidant activity measured by TEAC and FRAP assays (23.98 ± 0.01 µmol TE eq g-1 DW and 42.57 ± 0.04 µmol TE eq g-1 DW, respectively), a selective effect in reduting MCF-7 cells proliferation and a larger amount of chlorophyll a, carotenoids and phenolic content (18.40 ± 0.00 µg chlorophyll a mg-1 DW, 2.27 ± 0.00 mg carotenoids g-1 DW and 6.23 ± 0.01 mg GAE g-1 DW, respectively). A positive correlation between chlorophyll a and TEAC assay was observed, as well as between carotenoids and TEAC and FRAP assays, suggesting these compounds as important contributors to significant antioxidant activity. Violaxanthin, cholesterol and stigmasterol were present in larger amount in C. aquilonaris while C. regularis showed a higher amount of ß-carotene. These results suggest that these three ACOI eustigmatophytes are promising for applications in the improvement of human health, particularly in cancer prevention and treatment.


Assuntos
Antineoplásicos/farmacologia , Antioxidantes/farmacologia , Fatores Biológicos/farmacologia , Estramenópilas/crescimento & desenvolvimento , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Antioxidantes/química , Antioxidantes/isolamento & purificação , Fatores Biológicos/química , Fatores Biológicos/isolamento & purificação , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Clorofila A/química , Colesterol/química , Humanos , Células MCF-7 , Células PC-3 , Estigmasterol/química , Estramenópilas/química , Xantofilas/química , beta Caroteno/química
12.
Braz J Biol ; 81(3): 728-736, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32876175

RESUMO

Xylella fastidiosa is a plant-pathogenic bacterium that lives inside host xylem vessels, where it forms biofilm which is believed to be responsible for disrupting the passage of water and nutrients. Pectobacterium carotovorum is a Gram-negative plant-specific bacterium that causes not only soft rot in various plant hosts, but also blackleg in potato by plant cell wall degradation. Chagas disease, which is caused by Trypanosoma cruzi, has been commonly treated with nifurtimox and benzonidazole, two drugs that cause several side effects. As a result, the use of natural products for treating bacterial and neglected diseases has increased in recent years and plants have become a promising alternative to developing new medicines. Therefore, this study aimed to determine, for the first time, the chemical composition of essential oil from Psidium guajava flowers (PG-EO) and to evaluate its in vitro anti-Xylella fastidiosa, anti-Pectobacterium carotovorum, anti-Trypanosoma cruzi and cytotoxic activities. PG-EO was obtained by hydrodistillation in a Clevenger apparatus while its chemical composition was determined by gas chromatography-flame ionization detection (GC-FID) and gas chromatography-mass spectrometry (GC-MS). Major compounds identified in PG-EO were α-cadinol (37.8%), ß-caryophyllene (12.2%), nerolidol (9.1%), α-selinene (8.8%), ß-selinene (7.4%) and caryophyllene oxide (7.2%). Results showed that the PG-EO had strong trypanocidal activity against the trypomastigote forms of Trypanosoma cruzi (IC50 = 14.6 µg/mL), promising antibacterial activity against X. fastidiosa (MIC = 12.5 µg/mL) and P. carotovorum (MIC = 62.5 µg/mL), and moderate cytotoxicity against LLCMK2 adherent epithelial cells in the concentration range (CC50 = 250.5 µg/mL). In short, the PG-EO can be considered a new source of bioactive compounds for the development of pesticides and trypanocide drugs.


Assuntos
Myrtaceae , Óleos Voláteis , Psidium , Flores , Testes de Sensibilidade Microbiana , Óleos Voláteis/farmacologia , Folhas de Planta , Xylella
13.
Mater Today Bio ; 8: 100083, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33294837

RESUMO

The fast and non-invasive detection of odors and volatile organic compounds (VOCs) by gas sensors and electronic noses is a growing field of interest, mostly due to a large scope of potential applications. Additional drivers for the expansion of the field include the development of alternative and sustainable sensing materials. The discovery that isolated cross-linked polymeric structures of suberin spontaneously self-assemble as a film inspired us to develop new sensing composite materials consisting of suberin and a liquid crystal (LC). Due to their stimuli-responsive and optically active nature, liquid crystals are interesting probes in gas sensing. Herein, we report the isolation and the chemical characterization of two suberin types (from cork and from potato peels) resorting to analyses of gas chromatography-mass spectrometry (GC-MS), solution nuclear magnetic resonance (NMR), and X-ray photoelectron spectroscopy (XPS). The collected data highlighted their compositional and structural differences. Cork suberin showed a higher proportion of longer aliphatic constituents and is more esterified than potato suberin. Accordingly, when casted it formed films with larger surface irregularities and a higher C/O ratio. When either type of suberin was combined with the liquid crystal 5CB, the ensuing hybrid materials showed distinctive morphological and sensing properties towards a set of 12 VOCs (comprising heptane, hexane, chloroform, toluene, dichlormethane, diethylether, ethyl acetate, acetonitrile, acetone, ethanol, methanol, and acetic acid). The optical responses generated by the materials are reversible and reproducible, showing stability for 3 weeks. The individual VOC-sensing responses of the two hybrid materials are discussed taking as basis the chemistry of each suberin type. A support vector machines (SVM) algorithm based on the features of the optical responses was implemented to assess the VOC identification ability of the materials, revealing that the two distinct suberin-based sensors complement each other, since they selectively identify distinct VOCs or VOC groups. It is expected that such new environmentally-friendly gas sensing materials derived from natural diversity can be combined in arrays to enlarge selectivity and sensing capacity.

14.
Arq. bras. med. vet. zootec. (Online) ; 72(5): 1631-1638, Sept.-Oct. 2020. tab
Artigo em Português | LILACS, VETINDEX | ID: biblio-1131547

RESUMO

Avaliações com o intuito de mensurar marcadores de eficiência na performance esportiva do cavalo Crioulo são escassas e de fundamental importância no que tange às possíveis especificidades da raça. O objetivo do presente trabalho foi avaliar e determinar os padrões de frequência cardíaca, velocidade, concentração de lactato e gasto energético de equinos da raça Crioula durante provas credenciadoras ao Freio de Ouro. Tais variáveis foram avaliadas durante a realização das etapas funcionais da competição. Observaram-se flutuações superiores da variável frequência cardíaca (FC) durante a realização das etapas de Andadura, Figura, Volta sobre Patas e Esbarradas (And/fig/VSP) (203bpm) e menores valores na etapa Paleteada II (185bpm) (P<0,05). Em relação à velocidade, o maior valor atingido foi registrado na etapa de Paleteada II (39,7km/h). A concentração de lactato sanguíneo aferida se mostrou elevada em todas as fases da competição, sendo o maior valor observado na etapa de Paleteada II (14,5mmol/L) (P<0,05) e o menor durante a etapa de Mangueira I (9,3mmol/L). Superior gasto energético foi atribuído à etapa de And/Fig/VSP (853,28kcal/kgPV/min). Portanto, todas as etapas funcionais podem ser classificadas como anaeróbias, por apresentarem concentrações de lactato sanguíneo acima de 4mmol/L, e demandam alto gasto energético pelos competidores.(AU)


Evaluations of athletic performance markers of Crioulo breed horses are scarce yet fundamentally important regarding possible unique characteristics of this breed. This study aimed to evaluate and determine heart rate, speed, blood lactate and energy expenditure patterns of Crioulo breed horses during qualifying tests in the functional phases of the "Freio de Ouro" championship. Higher values of heart rate during the phases "andadura, figura, voltas sobre patas, esbarradas" (And/Fig/VSP) (203bpm) and lower values at "Paleteada II" (185bpm) (P<0.05) were noticed. Regarding speed variable, the maximum value was registered at "Paleteada II" (39.7km/h). During all the phases, blood lactate concentration was high, with the highest value found at "Paleteada II" (14.5mm/L) and the lowest during "Mangueira I" (9.3mm/L) (P<0.05). Superior energy expenditure was noticed in the "And/Fig/VSP" phase (853.28Kcal/kgPV/min). Thus, all functional phases can be classified as anaerobic, as blood lactate concentrations remained above 4mmol/L, with high energy demand of the horses.(AU)


Assuntos
Animais , Condicionamento Físico Animal/fisiologia , Ácido Láctico/sangue , Metabolismo Energético , Frequência Cardíaca/fisiologia , Cavalos/fisiologia
15.
Lett Appl Microbiol ; 71(5): 490-497, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32777092

RESUMO

The aim of this study was to synthesize and investigate the in vitro antifungal properties of 23 cinnamyl Schiff bases. In addition, cytotoxic effects of such cinnamyl Schiff bases against human lung, kidney or red blood cells were also checked. The compounds were synthesized in a single-step, 2 min of reaction under microwave irradiation produced up to 97% yield. Six of the 23 cinnamyl Schiff bases possessed antifungal activities against strains of Candida, Aspergillus, Fonsecaea and, particularly, Cryptococcus species. Indeed, cinnamyl Schiff bases 1 and 23 exhibited minimum inhibitory concentration (MIC) values more than twofold lower than fluconazole (FCZ) against all the Cryptococcus neoformans strains (MIC = 1·33, 1·4 and 5·2 µg ml-1 , respectively) and Cryptococcus gattii strains (MIC = 5·3, 2·8 and 9·2 µg ml-1 , respectively) (12 strains of each species) while cinnamyl Schiff base 11 was as potent as FCZ against all strains from both Cryptococcus species. No significant cytotoxic effects were observed for Schiff bases against human lung, kidney or red blood cells, all presenting selective indexes higher than 10. In conclusion, this study revealed cinnamyl Schiff bases, especially 1 and 23, as new lead anticryptococcal agents for the discovery of novel antifungal drugs. SIGNIFICANCE AND IMPACT OF THE STUDY: The occurrence and severity of fungal infections have increased in recent decades due to resistance to available antifungal drugs and the appearance of new emerging pathogens. Thus, the search for new antifungal agents is mandatory. From a series of 23 cinnamyl Schiff bases, two compounds (1 and 23) were interrogated as new anticryptococcal agents without significant cytotoxicity against human lung, kidney or red blood cells. In turns, these new Schiff bases are lead compounds for the discovery of novel antifungal drugs.


Assuntos
Antifúngicos/farmacologia , Micoses/tratamento farmacológico , Bases de Schiff/farmacologia , Antifúngicos/síntese química , Antineoplásicos/farmacologia , Aspergillus/efeitos dos fármacos , Candida/efeitos dos fármacos , Cryptococcus gattii/efeitos dos fármacos , Cryptococcus neoformans/efeitos dos fármacos , Fluconazol/farmacologia , Fonsecaea/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Bases de Schiff/síntese química
16.
Arq. bras. med. vet. zootec. (Online) ; 72(4): 1145-1153, July-Aug. 2020. tab, ilus
Artigo em Português | LILACS, VETINDEX | ID: biblio-1131471

RESUMO

O presente estudo avaliou o perfil mineral de Cálcio (Ca), Cobre (Cu) e Zinco (Zn) no estojo córneo pré e pós-desmame e sua associação com pigmentação, gênero e idade de potros da raça Crioula criados em pastagens nativas no Rio Grande do Sul. Foram coletadas amostras do casco de potros da raça Crioula 41 dias pré e 28 dias pós-desmame. Os teores de Ca, Cu e Zn variaram no casco fetal (571,0±39,4; 14,5±7,6 e 130,0±30,5mg/kg, respectivamente; P<0,05) e no definitivo (653,0±169,2; 33,8±11,5 e 69,3±36,8mg/kg, respectivamente; P<0,05), no pré (620,0±184; 17,2±21,2 e 103,0±75,5mg/kg, respectivamente; P<0,05) e no pós-desmame (517,5±181; 0 e 79,0±41,7mg/kg, respectivamente; P<0,05). Houve associação positiva (P<0,05) com a faixa etária no pré-desmame para Ca (r=0,5) e Cu (r=0,57), e negativa para Zn (r=-0,69; P<0,05). No pós-desmame, houve associação positiva (P<0,05) para Ca (r=0,36) e Zn (r=0,64) e negativa para Cu (r=-0,39; P<0,05). Tanto a pigmentação quanto o gênero não afetaram o perfil mineral. Conclui-se que há diferenças nas concentrações de Ca, Cu e Zn na epiderme do casco de potros da raça Crioula no pré e pós-desmame, independentemente da pigmentação e do gênero, onde as concentrações de Ca e Cu aumentam com a idade, enquanto as de Zn diminuem.(AU)


The aim of this study was to evaluate the mineral profile of Ca, Cu and Zn in the hoof horny capsule at pre and post-weaning and its association with pigmentation, gender and age range of Crioulo foals raised in native pastures in RS. Samples were collected from the epidermis of the Crioulo foal's hoof at two times, 41 pre and 28 post-weaning. The contents of Ca, Cu, Zn Varied in the fetal hoof ( 571.0±139.4, 14.5±7.6 and 130.0±30.5mg/kg, respectively, P<0.05) and definitive (653.0±169.2, 33.8±11.5 and 69.3±36.8mg/kg, respectively, P<0.05), in the pre (620.0±184, 17.2±21.2 and103.0±75.5mg/kg, respectively, P<0.05) and post-weaning (517.5±181, 0.1 and 79.0±41.7mg/kg, respectively, P<0.05).There was a positive association (P<0.05) with a preweaning age for Ca (r=0.5) and Cu (r=0.57) and negative for Zn (r=-0.69, P<0.05). In the post weaning there was a positive association (P<0.05) for Ca (r=0.36) and Zn (r=0.64) and negative for Cu (r=-0.39; P<0.05). Neither pigmentation nor gender affected the mineral profile. It is concluded that there are differences in Ca, Cu, Zn concentrations in the epidermis of foals of the crioulo breed at the pre and post weaning, regardless of pigmentation and sex, where Ca and Cu concentrations increase with age, while Zn concentrations decrease.(AU)


Assuntos
Animais , Pigmentação da Pele/fisiologia , Casco e Garras/citologia , Cavalos/crescimento & desenvolvimento , Minerais , Zinco , Cálcio , Cobre , Queratinas
17.
Arq. bras. med. vet. zootec. (Online) ; 72(4): 1433-1440, July-Aug. 2020. tab, ilus
Artigo em Português | LILACS, VETINDEX | ID: biblio-1131475

RESUMO

O objetivo do presente estudo foi analisar a dissimilaridade fenotípica de amostras populacionais de três linhagens de éguas Crioulas, uruguaia (La Invernada), argentina (Cardal) e chilena, para caracteres morfológicos, apontando as características de maior variância intra e entre as diferentes linhagens que são passíveis de seleção. Foram avaliadas 22 características morfológicas de 113 éguas da linhagem uruguaia "La Invernada", 38 argentinas "Cardal" e 73 chilenas puras, totalizando 224 éguas de cria pertencentes à raça Crioula. Para determinação das variáveis lineares e de perímetro, foi utilizada fita métrica, prumo, paquímetro e hipômetro. Verificou-se variabilidade nas características morfológicas entre as três linhagens (P<0,05), incluindo as características lineares altura, perímetro de tórax e perímetro de canela (P<0,01), consideradas de caráter impositivo para fins de registro. Maior variação fenotípica foi observada nas éguas da linhagem chilena em relação aos outros dois grupos genéticos (P<0,01). As características morfológicas altura garupa, perímetro rostral pescoço, comprimento metatarso, largura garupa, profundidade do tórax, comprimento dorsal pescoço e comprimento do corpo foram passíveis de seleção entre as éguas Crioulas pertencentes às linhagens argentina (Cardal), uruguaia (La Invernada) e chilena. Em conclusão, não há homogeneidade entre as linhagens estudadas, o que identifica a diversidade entre as linhagens de éguas Crioulas estudadas.(AU)


The aim of the study was to analyze the phenotypic dissimilarity of morphological characteristics of three strains of Criollo mares, Uruguian (La Invernada), Argentine (Cardal), and Chilena, pointing to the characteristics of higher variance within and among the different strains that are selectable. We evaluated 22 morphological characteristics of 113 mares of the Uruguaian line, 38 Argentines and 73 pure Chilean, totaling 224 breeding mares belonging to the criollo breed. For the determination of the linear and perimeter variables, a metric tape, plumb, pachymeter and hypometer were used. There was variability in the morphological characteristics between the three strains (P<0.05), including the linear characteristics of height, chest circumference and perimeter of cinnamon (P<0.01), considered as taxation for registration purposes. Higher phenotypic variation was observed in the mares of the Chilean line in relation to the other two genetic groups (P<0.01). The morphological characteristics of height croup, rostral perimeter neck, metatarsal length, croup width, chest depth, dorsal neck length, and body length were the selectable characteristics among the breeding mares belonging to the Argentine (Cardal), Uruguaian (La Invernada) and Chilena strains. In conclusion, there is no homogeneity between the studied strains, which identifies the diversity among the lines of Criollo mares studied.(AU)


Assuntos
Animais , Feminino , Fenótipo , Pesos e Medidas Corporais/veterinária , Cavalos/anatomia & histologia , Cavalos/genética
18.
Braz J Med Biol Res ; 53(9): e9877, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32725081

RESUMO

Clostridium difficile causes intestinal inflammation, which increases adenosine. We compared the expression of adenosine receptors (AR) subtypes A1, A2A, A2B, and A3 in HCT-8, IEC-6 cells, and isolated intestinal epithelial cells, challenged or not with Clostridium difficile toxin A and B (TcdA and TcdB) or infection (CDI). In HCT-8, TcdB induced an early A2BR expression at 6 h and a late A2AR expression at 6 and 24 h. In addition, both TcdA and TcdB increased IL-6 expression at all time-points (peak at 6 h) and PSB603, an A2BR antagonist, decreased IL-6 expression and production. In isolated cecum epithelial cells, TcdA induced an early expression of A2BR at 2s and 6 h, followed by a late expression of A2AR at 6 and 24 h and of A1R at 24 h. In CDI, A2AR and A2BR expressions were increased at day 3, but not at day 7. ARs play a role in regulating inflammation during CDI by inducing an early pro-inflammatory and a late anti-inflammatory response. The timing of interventions with AR antagonist or agonists may be of relevance in treatment of CDI.


Assuntos
Toxinas Bacterianas , Clostridioides difficile , Infecções por Clostridium , Receptores Purinérgicos P1/metabolismo , Animais , Anti-Inflamatórios , Proteínas de Bactérias , Modelos Animais de Doenças , Enterotoxinas , Infecções , Interleucina-6 , Regulação para Cima
19.
Food Res Int ; 134: 109210, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32517894

RESUMO

Human biomonitoring is an important tool to assess human exposure to chemicals, contributing to describe trends of exposure over time and to identify population groups that could be under risk. Aflatoxins are genotoxic and carcinogenic food contaminants causing hepatocellular carcinoma, the third leading cause of cancer deaths worldwide. In Portugal, scarce data are available regarding exposure to aflatoxins and no previous study used human biomonitoring data to comprehensively characterize the associated burden of disease. 24 h urine and first-morning urine paired samples were collected by 94 participants and were analyzed by liquid chromatography-tandem mass spectrometry for the quantitative determination of aflatoxins (B1, B2, G1, G2 and M1). Deterministic and probabilistic models were developed to assess the Portuguese exposure to aflatoxins and to estimate the health impact of this exposure, estimating the attributed Disability-Adjusted Life Years (DALYs). Aflatoxins were detected in a maximum of 13% (AFB1), 16% (AFB2), 1% (AFG1), 2% (AFG2) and 19% (AFM1) of the urine samples. Data obtained through the probabilistic approach revealed an estimated mean probable daily intake of 13.43 ng/kg body weight per day resulting in 0.13 extra cases of hepatocellular carcinoma, corresponding to mean annual DALYs of 172.8 for the Portuguese population (10291027 inhabitants). The present study generated for the first time and within a human biomonitoring study, reliable and crucial data to characterize the burden associated to the exposure to aflatoxins of the Portuguese population. The obtained results constitute an imperative support to risk managers in the establishment of preventive policy measures that contribute to ensure public health protection.


Assuntos
Aflatoxinas/administração & dosagem , Aflatoxinas/toxicidade , Adulto , Aflatoxinas/urina , Biomarcadores/urina , Dieta , Feminino , Contaminação de Alimentos , Humanos , Masculino , Pessoa de Meia-Idade , Vigilância da População , Portugal , Adulto Jovem
20.
Braz J Med Biol Res ; 53(6): e9031, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32401929

RESUMO

Malnutrition is still considered endemic in many developing countries. Malnutrition-enteric infections may cause lasting deleterious effects on lipid metabolism, especially in children living in poor settings. The regional basic diet (RBD), produced to mimic the Brazilian northeastern dietary characteristics (rich in carbohydrate and low in protein) has been used in experimental malnutrition models, but few studies have explored the effect of chronic RBD on liver function, a central organ involved in cholesterol metabolism. This study aimed to investigate whether RBD leads to liver inflammatory changes and altered reverse cholesterol metabolism in C57BL6/J mice compared to the control group, receiving a standard chow diet. To evaluate liver inflammation, ionized calcium-binding adapter protein-1 (IBA-1) positive cell counting, interleukin (IL)-1ß immunohistochemistry, and tumor necrosis factor (TNF)-α and IL-10 transcription levels were analyzed. In addition, we assessed reverse cholesterol transport by measuring liver apolipoprotein (Apo)E, ApoA-I, and lecithin-cholesterol acyltransferase (LCAT) by RT-PCR. Furthermore, serum alanine aminotransferase (ALT) was measured to assess liver function. RBD markedly impaired body weight gain compared with the control group (P<0.05). Higher hepatic TNF-α (P<0.0001) and IL-10 (P=0.001) mRNA levels were found in RBD-challenged mice, although without detectable non-alcoholic fatty liver disease. Marked IBA-1 immunolabeling and increased number of positive-IBA-1 cells were found in the undernourished group. No statistical difference in serum ALT was found. There was also a significant increase in ApoA mRNA expression in the undernourished group, but not ApoE and LCAT, compared with the control. Altogether our findings suggested that chronic RBD-induced malnutrition leads to liver inflammation with increased ApoA-I activity.


Assuntos
Apolipoproteína A-I/sangue , Dieta/efeitos adversos , Inflamação/metabolismo , Desnutrição/metabolismo , Animais , Apolipoproteína A-I/metabolismo , Brasil , Doença Crônica , Humanos , Inflamação/sangue , Inflamação/patologia , Fígado/metabolismo , Masculino , Desnutrição/sangue , Desnutrição/patologia , Camundongos , Camundongos Endogâmicos C57BL
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