Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 217
Filtrar
Mais filtros

Tipo de documento
Intervalo de ano de publicação
1.
J Am Chem Soc ; 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38918178

RESUMO

Metals are important cofactors in the metabolic processes of cyanobacteria, including photosynthesis, cellular respiration, DNA replication, and the biosynthesis of primary and secondary metabolites. In adaptation to the marine environment, cyanobacteria use metallophores to acquire trace metals when necessary as well as to reduce potential toxicity from excessive metal concentrations. Leptochelins A-C were identified as structurally novel metallophores from three geographically dispersed cyanobacteria of the genus Leptothoe. Determination of the complex structures of these metabolites presented numerous challenges, but they were ultimately solved using integrated data from NMR, mass spectrometry and deductions from the biosynthetic gene cluster. The leptochelins are comprised of halogenated linear NRPS-PKS hybrid products with multiple heterocycles that have potential for hexadentate and tetradentate coordination with metal ions. The genomes of the three leptochelin producers were sequenced, and retrobiosynthetic analysis revealed one candidate biosynthetic gene cluster (BGC) consistent with the structure of leptochelin. The putative BGC is highly homologous in all three Leptothoe strains, and all possess genetic signatures associated with metallophores. Postcolumn infusion of metals using an LC-MS metabolomics workflow performed with leptochelins A and B revealed promiscuous binding of iron, copper, cobalt, and zinc, with greatest preference for copper. Iron depletion and copper toxicity experiments support the hypothesis that leptochelin metallophores may play key ecological roles in iron acquisition and in copper detoxification. In addition, the leptochelins possess significant cytotoxicity against several cancer cell lines.

2.
Eur Heart J ; 44(4): 262-279, 2023 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-36477865

RESUMO

The first international guidance on antithrombotic therapy in the elderly came from the European Society of Cardiology Working Group on Thrombosis in 2015. This same group has updated its previous report on antiplatelet and anticoagulant drugs for older patients with acute or chronic coronary syndromes, atrial fibrillation, or undergoing surgery or procedures typical of the elderly (transcatheter aortic valve implantation and left atrial appendage closure). The aim is to provide a succinct but comprehensive tool for readers to understand the bases of antithrombotic therapy in older patients, despite the complexities of comorbidities, comedications and uncertain ischaemic- vs. bleeding-risk balance. Fourteen updated consensus statements integrate recent trial data and other evidence, with a focus on high bleeding risk. Guideline recommendations, when present, are highlighted, as well as gaps in evidence. Key consensus points include efforts to improve medical adherence through deprescribing and polypill use; adoption of universal risk definitions for bleeding, myocardial infarction, stroke and cause-specific death; multiple bleeding-avoidance strategies, ranging from gastroprotection with aspirin use to selection of antithrombotic-drug composition, dosing and duration tailored to multiple variables (setting, history, overall risk, age, weight, renal function, comedications, procedures) that need special consideration when managing older adults.


Assuntos
Fibrilação Atrial , Acidente Vascular Cerebral , Substituição da Valva Aórtica Transcateter , Humanos , Idoso , Fibrinolíticos/efeitos adversos , Resultado do Tratamento , Aspirina/efeitos adversos , Substituição da Valva Aórtica Transcateter/efeitos adversos , Hemorragia/induzido quimicamente , Hemorragia/prevenção & controle , Anticoagulantes , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/prevenção & controle , Acidente Vascular Cerebral/tratamento farmacológico , Fibrilação Atrial/tratamento farmacológico , Inibidores da Agregação Plaquetária/efeitos adversos
3.
Glycoconj J ; 40(4): 421-433, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37074623

RESUMO

Expression of sialyl Lewis X (SLeX) is a well-documented event during malignant transformation of cancer cells, and largely associates with their invasive and metastatic properties. Glycoproteins and glycolipids are the main carriers of SLeX, whose biosynthesis is known to be performed by different glycosyltransferases, namely by the family of ß-galactoside-α2,3-sialyltransferases (ST3Gals). In this study, we sought to elucidate the role of ST3GalIV in the biosynthesis of SLeX and in malignant properties of gastrointestinal (GI) cancer cells. By immunofluorescent screening, we selected SLeX-positive GI cancer cell lines and silenced ST3GalIV expression via CRISPR/Cas9. Flow cytometry, immunofluorescence and western blot analysis showed that ST3GalIV KO efficiently impaired SLeX expression in most cancer cell lines, with the exception of the colon cancer cell line LS174T. The impact of ST3GalIV KO in the biosynthesis of SLeX isomer SLeA and non sialylated Lewis X and A were also evaluated and overall, ST3GalIV KO led to a decreased expression of SLeA and an increased expression in both LeX and LeA. In addition, the abrogation of SLeX on GI cancer cells led to a reduction in cell motility. Furthermore, ST3GalVI KO was performed in LS174T ST3GalIV KO cells, resulting in the complete abolishment of SLeX expression and consequent reduced motility capacity of those cells. Overall, these findings portray ST3GalIV as the main, but not the only, enzyme driving the biosynthesis of SLeX in GI cancer cells, with a functional impact on cancer cell motility.


Assuntos
Neoplasias do Colo , Humanos , Movimento Celular , Neoplasias do Colo/genética , Neoplasias do Colo/metabolismo , Glicolipídeos , Oligossacarídeos/metabolismo , Antígeno Sialil Lewis X
4.
Neurol Sci ; 44(1): 319-327, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36094773

RESUMO

BACKGROUND: F abry disease (FD) is an X-linked lysosomal storage disorder with accumulation of globotriosylceramide, causing neurologic involvement mainly as acroparesthesias and cerebrovascular disease. Aseptic meningitis has been reported in 11 patients with FD, but no prior study has correlated alpha-galactosidase (GLA) specific variants with meningitis. We present in this manuscript a family in which a novel GLA pathogenic variant was associated with aseptic meningitis in 2 of 5 family members. METHODS: This study began with identifying the proband, then screening family members for FD symptoms and evaluating symptomatic individuals for genetic and biochemical status. All patients underwent magnetic resonance imaging, and those with headache underwent cerebrospinal fluid (CSF) analysis. RESULTS: Five patients (3 females) from a single family were included in this study. Mean age at diagnosis was 20.6 years. Two patients (40%) had aseptic meningitis; one of them also had cerebrovascular events. C-reactive protein and erythrocyte sedimentation rate were elevated during aseptic meningitis episodes. Both patients responded to intravenous methylprednisolone with resolution of fever, headache, and vomiting. One of them recurred and needed chronic immunosuppression with azathioprine. CONCLUSION: We described aseptic meningitis in a family with a novel GLA variant. Meningitis might be a common phenomenon in FD and not a particularity of this variant. Understanding the mechanisms underlying meningitis and its association with cerebrovascular events may lead to a new paradigm of treatment for stroke in these patients. Further prospective studies with CSF collection in patients with FD and recurrent headache could help to elucidate this question.


Assuntos
Doença de Fabry , Meningite Asséptica , Feminino , Humanos , Doença de Fabry/complicações , Doença de Fabry/tratamento farmacológico , Doença de Fabry/genética , Meningite Asséptica/etiologia , Estudos Prospectivos , Fenótipo , Cefaleia/complicações , Mutação
5.
Mar Drugs ; 20(12)2022 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-36547908

RESUMO

Nature-based and sustainably sourced cosmetics have been dominating the area of skincare products worldwide. Due to their antioxidant and antiaging properties, compounds from cyanobacteria, such as carotenoids and phycobiliproteins, may replace synthetic ingredients in cosmetic formulations and may be used in products such as sunscreens, skincare creams, and makeup. In this study, we evaluated the potential of acetonic and aqueous extracts from cyanobacteria strains of the genera Cyanobium and Leptothoe and from strains within Synechococcales and Oscillatoriales orders, for use in cosmetics. Extractions were sequentially performed with acetone and water. Extracts were firstly analyzed for their toxicity to keratinocytes, fibroblasts, and endothelial cells (HaCAT, 3T3L1 and hCMEC/D3, respectively). The non-cytotoxic extracts were characterized in terms of total proteins, carotenoids, chlorophyll, phenols, phycobiliproteins, and analyzed for their antioxidant potential against the superoxide anion radical (O2•−), and for their ability to inhibit key enzymes associated with the skin aging process. Aqueous extracts were richer in total proteins and phycobiliproteins. The aqueous extracts of Synechococcales cyanobacterium LEGE 181157 and Synechococcales cyanobacterium LEGE 181150 showed the highest value for total proteins (760.81 and 695.25 µg BSA mL−1dry extract, respectively) and the best values regarding O2•− scavenging (IC50 = 63.24 and 112.18 µg mL−1dry extract, respectively) with a significant negative correlation observed (p < 0.01). Moreover, aqueous extracts of Synechococcales cyanobacterium LEGE 181150 and Synechococcales cyanobacterium LEGE 181157 inhibited hyaluronidase, (IC50 of 483.86 and 645.06 µg mL−1dry extract, respectively), with a significant negative correlation with total proteins (p < 0.05), pointing out the contribution of these compounds to the biological activities observed. Acetonic extracts were richer in carotenoids and phenols. Zeaxanthin and ß-carotene were predominant among all strains, being present in higher amount in Cyanobium sp. LEGE 07175 (53.08 µg mg−1) and Leptothoe sp. LEGE 181156 (47.89 µg mg−1), respectively. The same strains also showed the highest values for collagenase inhibition at 750 µg mL−1dry extract (32.88 and 36.61%, respectively). Furthermore, Leptothoe sp. LEGE 181156 exhibited the lowest IC50 value for tyrosinase inhibition (465.92 µg mL−1dry extract) and Synechococcales cyanobacterium LEGE 181157 presented the best values for elastase inhibition (IC50 of 380.50 and IC25 of 51.43 µg mL−1dry extract). In general, cyanobacteria extracts demonstrated potential for being used for antiaging purposes, with aqueous extracts being more efficient at free radicals scavenging and acetonic ones at avoiding degradation of dermal matrix components.


Assuntos
Cosméticos , Cianobactérias , Antioxidantes/farmacologia , Células Endoteliais , Extratos Vegetais/farmacologia , Carotenoides/farmacologia , Cosméticos/farmacologia , Fenóis/farmacologia
6.
J Toxicol Environ Health A ; 84(18): 743-760, 2021 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-34120581

RESUMO

Jatropha mollissima is used in folk medicine as antimicrobial, antiparasitic, and larvicidal. However, few toxicogenetic studies have been carried out. Therefore, the aim of this study was to determine the phytochemical profile of ethanolic leaf extract of J. mollissima (EEJM) as well as potential cytotoxic, mutagenic, and antimutagenic properties. The EEJM was subjected to successive fractionation for the isolation of secondary metabolites, and five concentrations (0.01; 0.1; 1; 10 and 100 mg/ml) of extract were investigated using Allium cepa assay and the Somatic Mutation and Recombination (SMART) test. The mitotic index and % damage reduction were analyzed for A. cepa and the frequency of mutant hair for SMART. The presence of coumarins, alkaloids, flavonoids, saponins, and tannins was detected, while spinasterol and n-triacontane were the isolates identified for the first time for this species. EEJM did not exhibit cytotoxicity and was not mutagenic at 1 or 10 mg/ml using A. cepa and all concentrations of EEJM were not mutagenic in the SMART test. A cytoprotective effect was found at all concentrations. At 1 or 10 mg/ml EEJM exhibited antimutagenicity in A. cepa. In SMART, the protective effect was observed at 0.1 to 100 mg/ml EEJM. Our results demonstrate the important chemopreventive activity of EEJM, a desired quality in the search for natural anticarcinogenic compounds.


Assuntos
Jatropha/química , Testes de Mutagenicidade , Cebolas/efeitos dos fármacos , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/farmacologia , Substâncias Protetoras/farmacologia , Relação Dose-Resposta a Droga , Compostos Fitoquímicos/química , Extratos Vegetais/química , Folhas de Planta/química
7.
Mar Drugs ; 19(11)2021 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-34822504

RESUMO

The Blue Biotechnology and Ecotoxicology Culture Collection (LEGE-CC) holds a vast number of cyanobacteria whose chemical richness is still largely unknown. To expedite its bioactivity screening we developed a natural products library. Sixty strains and four environmental samples were chromatographed, using a semiautomatic HPLC system, yielding 512 fractions that were tested for their cytotoxic activity against 2D and 3D models of human colon carcinoma (HCT 116), and non-cancerous cell line hCMEC/D3. Six fractions showed high cytotoxicity against 2D and 3D cell models (group A), and six other fractions were selected by their effects on 3D cells (group B). The metabolome of each group was organized and characterized using the MolNetEnhancer workflow, and its processing with MetaboAnalyst allowed discrimination of the mass features with the highest fold change, and thus the ones that might be bioactive. Of those, mass features without precedented identification were mostly found in group A, indicating seven possible novel bioactive molecules, alongside in silico putative annotation of five cytotoxic compounds. Manual dereplication of group B tentatively identified nine pheophytin and pheophorbide derivatives. Our approach enabled the selection of 7 out of 60 cyanobacterial strains for anticancer drug discovery, providing new data concerning the chemical composition of these cyanobacteria.


Assuntos
Antineoplásicos/farmacologia , Cianobactérias , Animais , Antineoplásicos/química , Organismos Aquáticos , Produtos Biológicos , Linhagem Celular Tumoral/efeitos dos fármacos , Descoberta de Drogas , Humanos , Metabolômica
8.
Mar Drugs ; 19(12)2021 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-34940674

RESUMO

Lipids are one of the primary metabolites of microalgae and cyanobacteria, which enrich their utility in the pharmaceutical, feed, cosmetic, and chemistry sectors. This work describes the isolation, structural elucidation, and the antibiotic and antibiofilm activities of diverse lipids produced by different microalgae and cyanobacteria strains from two European collections (ACOI and LEGE-CC). Three microalgae strains and one cyanobacteria strain were selected for their antibacterial and/or antibiofilm activity after the screening of about 600 strains carried out under the NoMorFilm European project. The total organic extracts were firstly fractionated using solid phase extraction methods, and the minimum inhibitory concentration and minimal biofilm inhibitory concentration against an array of human pathogens were determined. The isolation was carried out by bioassay-guided HPLC-DAD purification, and the structure of the isolated molecules responsible for the observed activities was determined by HPLC-HRESIMS and NMR methods. Sulfoquinovosyldiacylglycerol, monogalactosylmonoacylglycerol, sulfoquinovosylmonoacylglycerol, α-linolenic acid, hexadeca-4,7,10,13-tetraenoic acid (HDTA), palmitoleic acid, and lysophosphatidylcholine were found among the different active sub-fractions selected. In conclusion, cyanobacteria and microalgae produce a great variety of lipids with antibiotic and antibiofilm activity against the most important pathogens causing severe infections in humans. The use of these lipids in clinical treatments alone or in combination with antibiotics may provide an alternative to the current treatments.


Assuntos
Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Cianobactérias , Lipídeos/farmacologia , Microalgas , Animais , Antibacterianos/química , Organismos Aquáticos , Lipídeos/química , Testes de Sensibilidade Microbiana , Staphylococcus aureus/efeitos dos fármacos
9.
J Mater Sci Mater Med ; 32(4): 39, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33792773

RESUMO

Biomaterials used in tissue regeneration processes represent a promising option for the versatility of its physical and chemical characteristics, allowing for assisting or speeding up the repair process stages. This research has characterized a polyurethane produced from castor oil monoacylglyceride (Ricinus communis L) and tested its effect on reconstructing bone defects in rat calvaria, comparing it with commercial castor oil polyurethane. The characterizations of the synthesized polyurethane have been performed by spectroscopy in the infrared region with Fourier transform (FTIR); thermogravimetric analysis (TG/DTG); X-ray diffraction (XRD) and Scanning Electron Microscopy (SEM). For the in vivo test, 24 animals have been used, divided into 3 groups: untreated group (UG); control group treated with Poliquil® castor polyurethane (PCP) and another group treated with castor polyurethane from the Federal University of Piauí - UFPI (CPU). Sixteen weeks after surgery, samples of the defects were collected for histological and histomorphometric analysis. FTIR analysis has shown the formation of monoacylglyceride and polyurethane. TG and DTG have indicated thermal stability of around 125 °C. XRD has determined the semi-crystallinity of the material. The polyurethane SEM has shown a smooth morphology with areas of recesses. Histological and histomorphometric analyzes have indicated that neither CPU nor PCP induced a significant inflammatory process, and CPU has shown, statistically, better performance in bone formation. The data obtained shows that CPU can be used in the future for bone reconstruction in the medical field.


Assuntos
Fraturas Ósseas/cirurgia , Monoglicerídeos/química , Poliuretanos/química , Ricinus/química , Animais , Materiais Biocompatíveis/química , Regeneração Óssea/efeitos dos fármacos , Substitutos Ósseos/farmacologia , Osso e Ossos/metabolismo , Óleo de Rícino/química , Consolidação da Fratura , Inflamação , Masculino , Teste de Materiais , Microscopia Eletrônica de Varredura , Osteogênese/efeitos dos fármacos , Ratos , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Difração de Raios X
10.
J Environ Sci Health B ; 56(9): 845-851, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34388052

RESUMO

This study evaluated differences in the efficiency of ozonation process to reduce the natural contamination of two mycotoxins, deoxynivalenol (DON) and zearalenone (ZEN), in wheat grains and particulate products. Three different products were used, each one representing a different structure and mycotoxin distribution: (1) wheat grains, with natural mycotoxin distribution inside and among the grains; (2) homemade pellets, with homogenous mycotoxin distribution; (3) ground homemade pellets, with homogeneous mycotoxin distribution, and smaller particles. The ozonation of naturally contaminated wheat grains did not reduce the concentrations of DON and ZEN. When the variability of contamination among replicates was reduced by the production of homemade pellets showed, the ozonation provides a reduction of 14% of ZEN concentration. Reducing the size of particles by grinding the homemade pellets, a reduction of DON (11%) and ZEN (31%) was observed, which was evidenced by the higher ozone consumption during the process. Therefore, some limitations of ozonation of grains and particulate products, such as particle dimensions and distribution of natural contamination of mycotoxins affect the degradation of DON and ZEN under real conditions. Because of this, further studies to evaluate the effectiveness of ozonation should also be performed in samples naturally contaminated to produce robustness results.


Assuntos
Fusarium , Micotoxinas , Ozônio , Tricotecenos , Zearalenona , Contaminação de Alimentos/análise , Micotoxinas/análise , Tricotecenos/análise
11.
Circulation ; 140(23): 1921-1932, 2019 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-31557056

RESUMO

BACKGROUND: The safety and efficacy of antithrombotic regimens may differ between patients with atrial fibrillation who have acute coronary syndromes (ACS), treated medically or with percutaneous coronary intervention (PCI), and those undergoing elective PCI. METHODS: Using a 2×2 factorial design, we compared apixaban with vitamin K antagonists and aspirin with placebo in patients with atrial fibrillation who had ACS or were undergoing PCI and were receiving a P2Y12 inhibitor. We explored bleeding, death and hospitalization, as well as death and ischemic events, by antithrombotic strategy in 3 prespecified subgroups: patients with ACS treated medically, patients with ACS treated with PCI, and those undergoing elective PCI. RESULTS: Of 4614 patients enrolled, 1097 (23.9%) had ACS treated medically, 1714 (37.3%) had ACS treated with PCI, and 1784 (38.8%) had elective PCI. Apixaban compared with vitamin K antagonist reduced International Society on Thrombosis and Haemostasis major or clinically relevant nonmajor bleeding in patients with ACS treated medically (hazard ratio [HR], 0.44 [95% CI, 0.28-0.68]), patients with ACS treated with PCI (HR, 0.68 [95% CI, 0.52-0.89]), and patients undergoing elective PCI (HR, 0.82 [95% CI, 0.64-1.04]; Pinteraction=0.052) and reduced death or hospitalization in the ACS treated medically (HR, 0.71 [95% CI, 0.54-0.92]), ACS treated with PCI (HR, 0.88 [95% CI, 0.74-1.06]), and elective PCI (HR, 0.87 [95% CI, 0.72-1.04]; Pinteraction=0.345) groups. Compared with vitamin K antagonists, apixaban resulted in a similar effect on death and ischemic events in the ACS treated medically, ACS treated with PCI, and elective PCI groups (Pinteraction=0.356). Aspirin had a higher rate of bleeding than did placebo in patients with ACS treated medically (HR, 1.49 [95% CI, 0.98-2.26]), those with ACS treated with PCI (HR, 2.02 [95% CI, 1.53-2.67]), and those undergoing elective PCI (HR, 1.91 [95% CI, 1.48-2.47]; Pinteraction=0.479). For the same comparison, there was no difference in outcomes among the 3 groups for the composite of death or hospitalization (Pinteraction=0.787) and death and ischemic events (Pinteraction=0.710). CONCLUSIONS: An antithrombotic regimen consisting of apixaban and a P2Y12 inhibitor without aspirin provides superior safety and similar efficacy in patients with atrial fibrillation who have ACS, whether managed medically or with PCI, and those undergoing elective PCI compared with regimens that include vitamin K antagonists, aspirin, or both. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov. Unique identifier: NCT02415400.


Assuntos
Síndrome Coronariana Aguda/tratamento farmacológico , Anticoagulantes/uso terapêutico , Aspirina/uso terapêutico , Fibrilação Atrial/tratamento farmacológico , Fármacos Cardiovasculares/uso terapêutico , Fibrinolíticos/uso terapêutico , Intervenção Coronária Percutânea , Inibidores da Agregação Plaquetária/uso terapêutico , Pirazóis/uso terapêutico , Piridonas/uso terapêutico , Síndrome Coronariana Aguda/complicações , Síndrome Coronariana Aguda/cirurgia , Idoso , Anticoagulantes/efeitos adversos , Fibrilação Atrial/complicações , Terapia Combinada , Gerenciamento Clínico , Quimioterapia Combinada , Procedimentos Cirúrgicos Eletivos , Feminino , Fibrinolíticos/efeitos adversos , Hemorragia/induzido quimicamente , Hemorragia/epidemiologia , Hospitalização , Humanos , Masculino , Pessoa de Meia-Idade , Inibidores da Agregação Plaquetária/efeitos adversos , Modelos de Riscos Proporcionais , Estudos Prospectivos , Antagonistas do Receptor Purinérgico P2Y/efeitos adversos , Antagonistas do Receptor Purinérgico P2Y/uso terapêutico , Resultado do Tratamento , Vitamina K/antagonistas & inibidores
12.
J Nat Prod ; 83(6): 1885-1890, 2020 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-32479093

RESUMO

Four natural lactylates of chlorinated fatty acids, chlorosphaerolactylates A-D (1-4), were isolated from the methanolic extract of the cyanobacterium Sphaerospermopsis sp. LEGE 00249 through a combination of bioassay-guided and MS-guided approaches. Compounds 1-4 are esters of (mono-, di-, or tri)chlorinated lauric acid and lactic acid, whose structures were assigned on the basis of spectrometric and spectroscopic methods inclusive of 1D and 2D NMR experiments. High-resolution mass-spectrometry data sets also demonstrated the existence of other minor components that were identified as chlorosphaero(bis)lactylate analogues. The chlorosphaerolactylates were tested for potential antibacterial, antifungal, and antibiofilm properties using bacterial and fungal clinical isolates. Compounds 1-4 showed a weak inhibitory effect on the growth of Staphylococcus aureus S54F9 and Candida parapsilosis SMI416, as well as on the biofilm formation of coagulase-negative Staphylococcus hominis FI31.


Assuntos
Anti-Infecciosos/química , Cianobactérias/química , Ácidos Graxos/química , Antibacterianos/farmacologia , Anti-Infecciosos/isolamento & purificação , Anti-Infecciosos/farmacologia , Antifúngicos/farmacologia , Biofilmes/efeitos dos fármacos , Candida/efeitos dos fármacos , Ácidos Graxos/isolamento & purificação , Ácidos Graxos/farmacologia , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Testes de Sensibilidade Microbiana , Estrutura Molecular , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus hominis/efeitos dos fármacos
13.
Biofouling ; 36(6): 631-645, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32715767

RESUMO

Cyanobacteria promote marine biofouling with significant impacts. A qualitative proteomic analysis, by LC-MS/MS, of planktonic and biofilm cells from two cyanobacteria was performed. Biofilms were formed on glass and perspex at two relevant hydrodynamic conditions for marine environments (average shear rates of 4 s-1 and 40 s-1). For both strains and surfaces, biofilm development was higher at 4 s-1. Biofilm development of Nodosilinea sp. LEGE 06145 was substantially higher than Nodosilinea sp. LEGE 06119, but no significant differences were found between surfaces. Overall, 377 and 301 different proteins were identified for Nodosilinea sp. LEGE 06145 and Nodosilinea sp. LEGE 06119. Differences in protein composition were more noticeable in biofilms formed under different hydrodynamic conditions than in those formed on different surfaces. Ribosomal and photosynthetic proteins were identified in most conditions. The characterization performed gives new insights into how shear rate and surface affect the planktonic to biofilm transition, from a structural and proteomics perspective.


Assuntos
Biofilmes , Cianobactérias , Plâncton , Proteômica , Cromatografia Líquida , Espectrometria de Massas em Tandem
14.
Environ Microbiol ; 21(11): 4411-4424, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31573125

RESUMO

Marine biofouling has severe economic impacts and cyanobacteria play a significant role as early surface colonizers. Despite this fact, cyanobacterial biofilm formation studies in controlled hydrodynamic conditions are scarce. In this work, computational fluid dynamics was used to determine the shear rate field on coupons that were placed inside the wells of agitated 12-well microtiter plates. Biofilm formation by three different cyanobacterial strains was assessed at two different shear rates (4 and 40 s-1 ) which can be found in natural ecosystems and using different surfaces (glass and perspex). Biofilm formation was higher under low shear conditions, and differences obtained between surfaces were not always statistically significant. The hydrodynamic effect was more noticeable during the biofilm maturation phase rather than during initial cell adhesion and optical coherence tomography showed that different shear rates can affect biofilm architecture. This study is particularly relevant given the cosmopolitan distribution of these cyanobacterial strains and the biofouling potential of these organisms.


Assuntos
Biofilmes , Cianobactérias/fisiologia , Hidrodinâmica
15.
J Thromb Thrombolysis ; 45(2): 213-221, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29270857

RESUMO

Despite the known protective cardiovascular effect of aspirin, former studies identified its prior exposure to an acute coronary syndrome (ACS) as an independent risk factor for adverse events. However, those studies did not reflect contemporary approaches. In the current study, we determine whether patients exposed to aspirin before an ACS have a worse cardiovascular risk profile and if it predicts higher risk of recurrent cardiovascular events or mortality. A cohort of patients enrolled in a national registry of ACS was analyzed according to prior exposure to aspirin. A propensity score standardized patients according to baseline comorbidities. Multivariable COX regression analysis was performed in unmatched and matched populations for a primary endpoint (composite of all-cause mortality and/or cardiovascular rehospitalization) and two secondary endpoints (all-cause mortality and cardiovascular rehospitalization, separately) at 1-year follow-up. Among 5533 ACS patients, 1763 were previously exposed to aspirin. They were older and had more comorbidities; contemporary approaches, both coronary angiography and percutaneous coronary angioplasty were less likely to be performed. Before matching the population, prior exposure to aspirin was an independent predictor of primary composite endpoint (p = 0.002) and cardiovascular rehospitalization as the secondary endpoint (p = 0.001). There were no statistically significant differences between both groups in the multivariable model for the primary or secondary endpoints after matching. Previous exposure to aspirin identified ACS patients with worse baseline characteristics, establishing its role as a cardiovascular risk marker. However, our data do not support including aspirin pretreatment in risk stratification scores as an adverse prognostic variable.


Assuntos
Síndrome Coronariana Aguda/diagnóstico , Aspirina/efeitos adversos , Idoso , Aspirina/uso terapêutico , Doenças Cardiovasculares/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Pontuação de Propensão , Sistema de Registros , Medição de Risco , Fatores de Risco , Resultado do Tratamento
16.
Lancet ; 387(10016): 349-356, 2016 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-26547100

RESUMO

BACKGROUND: REG1 is a novel anticoagulation system consisting of pegnivacogin, an RNA aptamer inhibitor of coagulation factor IXa, and anivamersen, a complementary sequence reversal oligonucleotide. We tested the hypothesis that near complete inhibition of factor IXa with pegnivacogin during percutaneous coronary intervention, followed by partial reversal with anivamersen, would reduce ischaemic events compared with bivalirudin, without increasing bleeding. METHODS: We did a randomised, open-label, active-controlled, multicentre, superiority trial to compare REG1 with bivalirudin at 225 hospitals in North America and Europe. We planned to randomly allocate 13,200 patients undergoing percutaneous coronary intervention in a 1:1 ratio to either REG1 (pegnivacogin 1 mg/kg bolus [>99% factor IXa inhibition] followed by 80% reversal with anivamersen after percutaneous coronary intervention) or bivalirudin. Exclusion criteria included ST segment elevation myocardial infarction within 48 h. The primary efficacy endpoint was the composite of all-cause death, myocardial infarction, stroke, and unplanned target lesion revascularisation by day 3 after randomisation. The principal safety endpoint was major bleeding. Analysis was by intention to treat. This trial is registered at ClinicalTrials.gov, identifier NCT01848106. The trial was terminated early after enrolment of 3232 patients due to severe allergic reactions. FINDINGS: 1616 patients were allocated REG1 and 1616 were assigned bivalirudin, of whom 1605 and 1601 patients, respectively, received the assigned treatment. Severe allergic reactions were reported in ten (1%) of 1605 patients receiving REG1 versus one (<1%) of 1601 patients treated with bivalirudin. The composite primary endpoint did not differ between groups, with 108 (7%) of 1616 patients assigned REG1 and 103 (6%) of 1616 allocated bivalirudin reporting a primary endpoint event (odds ratio [OR] 1·05, 95% CI 0·80-1·39; p=0·72). Major bleeding was similar between treatment groups (seven [<1%] of 1605 receiving REG1 vs two [<1%] of 1601 treated with bivalirudin; OR 3·49, 95% CI 0·73-16·82; p=0·10), but major or minor bleeding was increased with REG1 (104 [6%] vs 65 [4%]; 1·64, 1·19-2·25; p=0·002). INTERPRETATION: The reversible factor IXa inhibitor REG1, as currently formulated, is associated with severe allergic reactions. Although statistical power was limited because of early termination, there was no evidence that REG1 reduced ischaemic events or bleeding compared with bivalirudin. FUNDING: Regado Biosciences Inc.


Assuntos
Anticoagulantes/uso terapêutico , Aptâmeros de Nucleotídeos/uso terapêutico , Fator IXa/antagonistas & inibidores , Fragmentos de Peptídeos/uso terapêutico , Intervenção Coronária Percutânea , Idoso , Coagulantes/administração & dosagem , Hipersensibilidade a Drogas/epidemiologia , Término Precoce de Ensaios Clínicos , Europa (Continente)/epidemiologia , Feminino , Hemorragia/epidemiologia , Hirudinas , Humanos , Masculino , Pessoa de Meia-Idade , América do Norte/epidemiologia , Oligonucleotídeos/administração & dosagem , Proteínas Recombinantes/uso terapêutico
17.
Clin Chem ; 63(1): 307-315, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28062625

RESUMO

BACKGROUND: Cardiac troponin I, measured with a high-sensitivity assay (hs-TnI), is well-established for risk prediction in acute coronary syndromes. However, its prognostic role in stable atherosclerotic disease, particularly for future myocardial infarction (MI), is less well defined. METHODS: We measured hs-TnI (Abbott ARCHITECT) in 15833 patients with prior MI, ischemic stroke, or peripheral arterial disease from the placebo-controlled Thrombin Receptor Antagonist in Secondary Prevention of Atherothrombotic Ischemic Events (TRA 2°P)-Thrombolysis in Myocardial Infarction (TIMI) 50 trial of the platelet inhibitor vorapaxar, excluding patients with recent MI (<30 days). hs-TnI was categorized into 5 groups based on the detection limit (1.9 ng/L), 99th percentile reference limit (26 ng/L), and tertiles in between (1.9-26 ng/L), as well as sex-specific reference limits. RESULTS: Higher hs-TnI concentration was associated with older age, male sex, and increased atherosclerosis burden. hs-TnI identified a graded 3-year risk of cardiovascular death, MI, or stroke from 5.0% to 18.6% (P < 0.001), driven by cardiovascular death and MI (P < 0.001). This risk was independent of established clinical risk indicators, B-type natriuretic peptide and C-reactive protein [adjusted hazard ratio 2.70 (95% CI, 1.96-3.71), P < 0.001 for hs-TnI >26 ng/L vs <1.9 ng/L]. In patients with prior MI, there was a pattern of greater absolute benefit with vorapaxar in patients with an increased hs-TnI (absolute risk difference 1.9% with hs-TnI >26 ng/L vs 0.3% with hs-TnI <1.9 ng/L; P interaction = 0.82). CONCLUSIONS: In stable patients with established atherosclerosis, hs-TnI concentrations effectively stratified the risk of new or recurrent cardiovascular (CV) events, in particular CV death and MI. High-risk patients with prior MI identified by increased hs-TnI had a substantial absolute improvement in net clinical outcome with vorapaxar.


Assuntos
Infarto do Miocárdio/sangue , Infarto do Miocárdio/diagnóstico , Troponina I/sangue , Idoso , Biomarcadores/sangue , Método Duplo-Cego , Feminino , Humanos , Lactonas/uso terapêutico , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/tratamento farmacológico , Infarto do Miocárdio/mortalidade , Piridinas/uso terapêutico
18.
Europace ; 19(11): 1757-1758, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-29096024

RESUMO

Atrial fibrillation (AF) is a major worldwide public health problem, and AF in association with valvular heart disease (VHD) is also common. However, management strategies for this group of patients have been less informed by randomized trials, which have largely focused on 'non-valvular AF' patients. Thrombo-embolic risk also varies according to valve lesion and may also be associated with CHA2DS2VASc score risk factor components, rather than only the valve disease being causal. Given marked heterogeneity in the definition of valvular and non-valvular AF and variable management strategies, including non-vitamin K antagonist oral anticoagulants (NOACs) in patients with VHD other than prosthetic heart valves or haemodynamically significant mitral valve disease, there is a need to provide expert recommendations for professionals participating in the care of patients presenting with AF and associated VHD. To address this topic, a Task Force was convened by the European Heart Rhythm Association (EHRA) and European Society of Cardiology (ESC) Working Group on Thrombosis, with representation from the ESC Working Group on Valvular Heart Disease, Heart Rhythm Society (HRS), Asia Pacific Heart Rhythm Society (APHRS), South African Heart (SA Heart) Association and Sociedad Latinoamericana de Estimulación Cardíaca y Electrofisiología (SOLEACE) with the remit to comprehensively review the published evidence, and to publish a joint consensus document on the management of patients with AF and associated VHD, with up-to-date consensus recommendations for clinical practice for different forms of VHD. This consensus document proposes that the term 'valvular AF' is outdated and given that any definition ultimately relates to the evaluated practical use of oral anticoagulation (OAC) type, we propose a functional Evaluated Heartvalves, Rheumatic or Artificial (EHRA) categorization in relation to the type of OAC use in patients with AF, as follows: (i) EHRA Type 1 VHD, which refers to AF patients with 'VHD needing therapy with a Vitamin K antagonist (VKA); and (ii) EHRA Type 2 VHD, which refers to AF patients with 'VHD needing therapy with a VKA or a Non-VKA oral anticoagulant (NOAC)', also taking into consideration CHA2DS2VASc score risk factor components. This consensus document also summarizes current developments in the field, and provides general recommendations for the management of these patients based on the principles of evidence-based medicine.


Assuntos
Fibrilação Atrial/tratamento farmacológico , Fibrinolíticos/uso terapêutico , Doenças das Valvas Cardíacas/tratamento farmacológico , Implante de Prótese de Valva Cardíaca/instrumentação , Próteses Valvulares Cardíacas , Acidente Vascular Cerebral/prevenção & controle , Tromboembolia/prevenção & controle , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/epidemiologia , Tomada de Decisão Clínica , Consenso , Medicina Baseada em Evidências , Fibrinolíticos/efeitos adversos , Doenças das Valvas Cardíacas/diagnóstico , Doenças das Valvas Cardíacas/epidemiologia , Implante de Prótese de Valva Cardíaca/efeitos adversos , Hemorragia/induzido quimicamente , Humanos , Medição de Risco , Fatores de Risco , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/epidemiologia , Tromboembolia/diagnóstico , Tromboembolia/epidemiologia , Resultado do Tratamento
19.
J Thromb Thrombolysis ; 44(2): 145-153, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28608165

RESUMO

The PLATelet inhibition and patient Outcomes (PLATO) trial showed that treatment with ticagrelor reduced the rate of death due to vascular causes, myocardial infarction and stroke when compared to clopidogrel in patients with ST-elevation or non-ST-elevation acute coronary syndrome (ACS). While the comparative benefit of ticagrelor over clopidogrel increased over time, event rates accrued in both groups during the study period. The purpose of our biomarker-based exploratory analysis was to determine whether long-term platelet inhibition may be associated with platelet adaptation. A sample of 4000 participants from the PLATO trial also consented to participate in a prospectively designed biomarker substudy. Blood samples were procured at baseline, immediately prior to hospital discharge and at 1 and 6 months. Markers of platelet activity, including platelet count, serum CD40-ligand and soluble P-selectin were analyzed. Mean levels were compared at discharge, 1 and 6 months following study drug initiation-first for all patients and subsequently stratified by treatment group. A linear mixed model was used to estimate the short-term change rate (baseline to 1 month) and long-term change rate (1-6 months) for each biomarker. A Cox proportional hazards model was used to calculate hazard ratios for each change in biomarker over the two time periods examined: baseline to 1 month and 1 to 6 months. Prior to randomized treatment (baseline), sCD40 ligand and sP-selectin levels were elevated above the normal range of the assay (0.39 and 33.5 µg/L, respectively). The mean level of each biomarker was significantly different at 1 month compared to baseline (p < 0.0001). When stratified by treatment group, at 1 month patients treated with ticagrelor had a larger increase in platelet count compared to those treated with clopidogrel (p < 0.0001). Similarly, when comparing biomarker levels for all patients at 6 months with those at 1 month, each differed significantly (p < 0.05). There was no significant difference between treatment groups during this time period. The rate of change for both platelet count and sP-selectin were significantly different between baseline and 1 month when compared to the 1 to 6-month time period (p < 0.0001). When comparing treatment groups, the rate of increase in platelets from baseline to 1 month was greater for patients treated with ticagrelor (p < 0.0001). This was no longer observed in the 1 to 6-month interval. Using a Cox proportional hazard model, the increase in platelet count from 1 to 6 months was associated with ischemic-thrombotic events, while sCD40 ligand decrease from 1 to 6 months was associated with hemorrhagic events. There were no differences between treatment groups for the associations with clinical endpoints. Dynamic changes in platelet count, sCD-40 ligand and sP-selectin occur over time among patients with ACS. Platelet-directed therapy with a P2Y12 receptor inhibitor in combination with aspirin modestly impacts the expression of these biomarkers. Platelet count and sCD40 ligand may offer modest overall predictive value for future ischemic-thrombotic or hemorrhagic clinical events, respectively. The existence of a platelet adaptome and its overall clinical significance among patients at risk for thrombotic events will require a more in-depth and platelet-biology specific investigation.


Assuntos
Síndrome Coronariana Aguda/tratamento farmacológico , Aspirina/farmacologia , Biomarcadores/sangue , Plaquetas/efeitos dos fármacos , Inibidores da Agregação Plaquetária/administração & dosagem , Antagonistas do Receptor Purinérgico P2Y/farmacologia , Adenosina/administração & dosagem , Adenosina/análogos & derivados , Adenosina/farmacologia , Adenosina/uso terapêutico , Idoso , Aspirina/uso terapêutico , Ligante de CD40/sangue , Clopidogrel , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Selectina-P/sangue , Inibidores da Agregação Plaquetária/farmacologia , Contagem de Plaquetas , Estudos Prospectivos , Antagonistas do Receptor Purinérgico P2Y/administração & dosagem , Ticagrelor , Ticlopidina/administração & dosagem , Ticlopidina/análogos & derivados , Ticlopidina/farmacologia , Ticlopidina/uso terapêutico , Fatores de Tempo
20.
Echocardiography ; 34(7): 1099-1101, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28517030

RESUMO

We report a clinical case of a 40-year-old male with surgically corrected congenital heart disease (CHD) 10 years earlier: closure of ostium primum, mitral annuloplasty, and aortic valve and root surgery. The patient was admitted with acute heart failure. Transesophageal echocardiography (TEE) revealed a dysmorphic and severely incompetent aortic valve, a partial tear of the mitral valve cleft repair and annuloplasty ring dehiscence. A true left ventricular-to-right atrial shunt confirmed a direct Gerbode defect. The authors aim to discuss the diagnostic challenge of adult CHD, namely the key role of TEE on septal defects and valve regurgitations description.


Assuntos
Ecocardiografia Transesofagiana/métodos , Cardiopatias Congênitas/complicações , Insuficiência Cardíaca/diagnóstico por imagem , Doenças das Valvas Cardíacas/diagnóstico por imagem , Doença Aguda , Adulto , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/fisiopatologia , Valva Aórtica/cirurgia , Cardiopatias Congênitas/fisiopatologia , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/cirurgia , Doenças das Valvas Cardíacas/fisiopatologia , Doenças das Valvas Cardíacas/cirurgia , Implante de Prótese de Valva Cardíaca , Humanos , Masculino , Valva Mitral/diagnóstico por imagem , Valva Mitral/fisiopatologia , Valva Mitral/cirurgia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA