Heterofucans from the Brown Seaweed Canistrocarpus cervicornis with Anticoagulant and Antioxidant Activities

Fucan is a term used to denominate a family of sulfated polysaccharides rich in sulfated l-fucose. We extracted six fucans from Canistrocarpus cervicornis by proteolytic digestion followed by sequential acetone precipitation. These heterofucans are composed mainly of fucose, glucuronic acid, galactose and sulfate. No polysaccharide was capable of prolonging prothrombin time (PT) at the concentration assayed. However, all polysaccharides prolonged activated partial thromboplastin time (aPTT). Four sulfated polysaccharides (CC-0.3/CC-0.5/CC-0.7/CC-1.0) doubled aPTT with only 0.1 mg/mL of plasma, only 1.25-fold less than Clexane®, a commercial low molecular weight heparin. Heterofucans exhibited total antioxidant capacity, low hydroxyl radical scavenging activity, good superoxide radical scavenging efficiency (except CC-1.0), and excellent ferrous chelating ability (except CC-0.3). These results clearly indicate the beneficial effect of C. cervicornis polysaccharides as anticoagulants and antioxidants. Further purification steps and additional studies on structural features as well as in vivo experiments are needed to test the viability of their use as therapeutic agents

Heterofucan from Sargassum filipendula Induces Apoptosis in HeLa Cells

Fucan is a term used to denominate a family of sulfated polysaccharides rich in sulfated l-fucose. Heterofucan SF-1.5v was extracted from the brown seaweed Sargassum filipendula by proteolytic digestion followed by sequential acetone precipitation. This fucan showed antiproliferative activity on Hela cells and induced apoptosis. However, SF-1.5v was not able to activate caspases. Moreover, SF-1.5v induced glycogen synthase kinase (GSK) activation, but this protein is not involved in the heterofucan SF-1.5v induced apoptosis mechanism. In addition, ERK, p38, p53, pAKT and NFκB were not affected by the presence of SF-1.5v. We determined that SF-1.5v induces apoptosis in HeLa mainly by mitochondrial release of apoptosis-inducing factor (AIF) into cytosol. In addition, SF-1.5v decreases the expression of anti-apoptotic protein Bcl-2 and increased expression of apoptogenic protein Bax. These results are significant in that they provide a mechanistic framework for further exploring the use of SF-1.5v as a novel chemotherapeutics against human cervical cancer

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

Diretrizes Brasileiras de Medidas da Pressão Arterial Dentro e Fora do Consultório – 2023

Hypertension is one of the primary modifiable risk factors for morbidity and mortality worldwide, being a major risk factor for coronary artery disease, stroke, and kidney failure. Furthermore, it is highly prevalent, affecting more than one-third of the global population. Blood pressure measurement is a MANDATORY procedure in any medical care setting and is carried out by various healthcare professionals. However, it is still commonly performed without the necessary technical care. Since the diagnosis relies on blood pressure measurement, it is clear how important it is to handle the techniques, methods, and equipment used in its execution with care. It should be emphasized that once the diagnosis is made, all short-term, medium-term, and long-term investigations and treatments are based on the results of blood pressure measurement. Therefore, improper techniques and/or equipment can lead to incorrect diagnoses, either underestimating or overestimating values, resulting in inappropriate actions and significant health and economic losses for individuals and nations. Once the correct diagnosis is made, as knowledge of the importance of proper treatment advances, with the adoption of more detailed normal values and careful treatment objectives towards achieving stricter blood pressure goals, the importance of precision in blood pressure measurement is also reinforced. Blood pressure measurement (described below) is usually performed using the traditional method, the so-called casual or office measurement. Over time, alternatives have been added to it, through the use of semi-automatic or automatic devices by the patients themselves, in waiting rooms or outside the office, in their own homes, or in public spaces. A step further was taken with the use of semi-automatic devices equipped with memory that allow sequential measurements outside the office (ABPM; or HBPM) and other automatic devices that allow programmed measurements over longer periods (HBPM). Some aspects of blood pressure measurement can interfere with obtaining reliable results and, consequently, cause harm in decision-making. These include the importance of using average values, the variation in blood pressure during the day, and short-term variability. These aspects have encouraged the performance of a greater number of measurements in various situations, and different guidelines have advocated the use of equipment that promotes these actions. Devices that perform HBPM or ABPM, which, in addition to allowing greater precision, when used together, detect white coat hypertension (WCH), masked hypertension (MH), sleep blood pressure alterations, and resistant hypertension (RHT) (defined in Chapter 2 of this guideline), are gaining more and more importance. Taking these details into account, we must emphasize that information related to diagnosis, classification, and goal setting is still based on office blood pressure measurement, and for this reason, all attention must be given to the proper execution of this procedure.La hipertensión arterial (HTA) es uno de los principales factores de riesgo modificables para la morbilidad y mortalidad en todo el mundo, siendo uno de los mayores factores de riesgo para la enfermedad de las arterias coronarias, el accidente cerebrovascular (ACV) y la insuficiencia renal. Además, es altamente prevalente y afecta a más de un tercio de la población mundial. La medición de la presión arterial (PA) es un procedimiento OBLIGATORIO en cualquier atención médica o realizado por diferentes profesionales de la salud. Sin embargo, todavía se realiza comúnmente sin los cuidados técnicos necesarios. Dado que el diagnóstico se basa en la medición de la PA, es claro el cuidado que debe haber con las técnicas, los métodos y los equipos utilizados en su realización. Debemos enfatizar que una vez realizado el diagnóstico, todas las investigaciones y tratamientos a corto, mediano y largo plazo se basan en los resultados de la medición de la PA. Por lo tanto, las técnicas y/o equipos inadecuados pueden llevar a diagnósticos incorrectos, subestimando o sobreestimando valores y resultando en conductas inadecuadas y pérdidas significativas para la salud y la economía de las personas y las naciones. Una vez realizado el diagnóstico correcto, a medida que avanza el conocimiento sobre la importancia del tratamiento adecuado, con la adopción de valores de normalidad más detallados y objetivos de tratamiento más cuidadosos hacia metas de PA más estrictas, también se refuerza la importancia de la precisión en la medición de la PA. La medición de la PA (descrita a continuación) generalmente se realiza mediante el método tradicional, la llamada medición casual o de consultorio. Con el tiempo, se han agregado alternativas a través del uso de dispositivos semiautomáticos o automáticos por parte del propio paciente, en salas de espera o fuera del consultorio, en su propia residencia o en espacios públicos. Se dio un paso más con el uso de dispositivos semiautomáticos equipados con memoria que permiten mediciones secuenciales fuera del consultorio (AMPA; o MRPA) y otros automáticos que permiten mediciones programadas durante períodos más largos (MAPA). Algunos aspectos en la medición de la PA pueden interferir en la obtención de resultados confiables y, en consecuencia, causar daños en las decisiones a tomar. Estos incluyen la importancia de usar valores promedio, la variación de la PA durante el día y la variabilidad a corto plazo. Estos aspectos han alentado la realización de un mayor número de mediciones en diversas situaciones, y diferentes pautas han abogado por el uso de equipos que promuevan estas acciones. Los dispositivos que realizan MRPA o MAPA, que además de permitir una mayor precisión, cuando se usan juntos, detectan la hipertensión de bata blanca (HBB), la hipertensión enmascarada (HM), las alteraciones de la PA durante el sueño y la hipertensión resistente (HR) (definida en el Capítulo 2 de esta guía), están ganando cada vez más importancia. Teniendo en cuenta estos detalles, debemos enfatizar que la información relacionada con el diagnóstico, la clasificación y el establecimiento de objetivos todavía se basa en la medición de la presión arterial en el consultorio, y por esta razón, se debe prestar toda la atención a la ejecución adecuada de este procedimiento.A hipertensão arterial (HA) é um dos principais fatores de risco modificáveis para morbidade e mortalidade em todo o mundo, sendo um dos maiores fatores de risco para doença arterial coronária, acidente vascular cerebral (AVC) e insuficiência renal. Além disso, é altamente prevalente e atinge mais de um terço da população mundial. A medida da PA é procedimento OBRIGATÓRIO em qualquer atendimento médico ou realizado por diferentes profissionais de saúde. Contudo, ainda é comumente realizada sem os cuidados técnicos necessários. Como o diagnóstico se baseia na medida da PA, fica claro o cuidado que deve haver com as técnicas, os métodos e os equipamentos utilizados na sua realização. Deve-se reforçar que, feito o diagnóstico, toda a investigação e os tratamentos de curto, médio e longo prazos são feitos com base nos resultados da medida da PA. Assim, técnicas e/ou equipamentos inadequados podem levar a diagnósticos incorretos, tanto subestimando quanto superestimando valores e levando a condutas inadequadas e grandes prejuízos à saúde e à economia das pessoas e das nações. Uma vez feito o diagnóstico correto, na medida em que avança o conhecimento da importância do tratamento adequado, com a adoção de valores de normalidade mais detalhados e com objetivos de tratamento mais cuidadosos no sentido do alcance de metas de PA mais rigorosas, fica também reforçada a importância da precisão na medida da PA. A medida da PA (descrita a seguir) é habitualmente feita pelo método tradicional, a assim chamada medida casual ou de consultório. Ao longo do tempo, foram agregadas alternativas a ela, mediante o uso de equipamentos semiautomáticos ou automáticos pelo próprio paciente, nas salas de espera ou fora do consultório, em sua própria residência ou em espaços públicos. Um passo adiante foi dado com o uso de equipamentos semiautomáticos providos de memória que permitem medidas sequenciais fora do consultório (AMPA; ou MRPA) e outros automáticos que permitem medidas programadas por períodos mais prolongados (MAPA). Alguns aspectos na medida da PA podem interferir na obtenção de resultados fidedignos e, consequentemente, causar prejuízo nas condutas a serem tomadas. Entre eles, estão: a importância de serem utilizados valores médios, a variação da PA durante o dia e a variabilidade a curto prazo. Esses aspectos têm estimulado a realização de maior número de medidas em diversas situações, e as diferentes diretrizes têm preconizado o uso de equipamentos que favoreçam essas ações. Ganham cada vez mais espaço os equipamentos que realizam MRPA ou MAPA, que, além de permitirem maior precisão, se empregados em conjunto, detectam a HA do avental branco (HAB), HA mascarada (HM), alterações da PA no sono e HA resistente (HAR) (definidos no Capítulo 2 desta diretriz). Resguardados esses detalhes, devemos ressaltar que as informações relacionadas a diagnóstico, classificação e estabelecimento de metas ainda são baseadas na medida da PA de consultório e, por esse motivo, toda a atenção deve ser dada à realização desse procedimento

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

Modo de ação de uma ramnana sulfatada em células endoteliais e musculares lisas: potencial uso na prevenção da disfunção endotelial

Endothelial dysfunction can cause atherosclerosis, a disease characterized by accumulation of plaques containing lipids in the subendothelial layer of blood vessels. The endothelial glycocalyx maintains the homeostasis between the blood and the endothelial cells, and changes in their structure can cause disease. Seaweed sources are sulfated polysaccharides that have different pharmacological properties, among which we highlight the antioxidant activity, anti-inflammatory, anticoagulant and antithrombotic. The objective of this study was to evaluate the effects of a sulfated ramnana (RS) obtained from the algae Monostroma nitidum in endothelial and smooth muscle cells as well as in aortic rings, as well as describe its probable mechanism of action. It was found that the RS does not affect cell viability in 24 hours at concentrations up to 100 ?g/ml and is able to increase the marking glycocalyx by WGA lectin observed in confocal microscopy for both cell lines and also in the aortic ring mice. There is an increase in hyaluronic acid synthesis by such cells treated with RS and that hyaluronic acid has a high molecular weight. By metabolic labeling with radioactive sulfate was found to RS-treated cells increased the synthesis of sulfated glycosaminoglycans highlighting the heparan sulfate. This heparan sulfate was analyzed and their structure was observed that there is an increase in the proportion of trisulfated disaccharide structure typical of the heparins. It was observed an increase in the expression of enzymes responsible for the synthesis and modification of these glycosaminoglycans. Using confocal microscopy and FRET assay it was proven that RS binds to fibronectin in the extracellular matrix. It was shown that RS actives cell signaling by FAK, Src and ERK pathway increasing intracellular calcium levels and nitric oxide production. Finally it was observed that RS is also capable of inhibiting angiogenesis in assay formation of capillary structures in matrigel and also in the three-dimensional test in aortic ring angiogenesis. The results indicate that RS acts increasing and structurally modifying the glycocalyx in the derived aortic cells, stimulate the synthesis of heparan sulfate rich in trisulfated disaccharide, a typical structure of heparins with potent antithrombotic effect, as well as high molecular weight hyaluronic acid which is known to be anti-atherogenic and anti-angiogenic, increase nitric oxide synthesis and inhibit angiogenesis itself presents itself as a possible therapeutic agent to prevent the development of atherosclerosis and thrombus formation in function of the various beneficial effects on cells that can prevent different stages of these pathological processes.A disfunção endotelial pode causar aterosclerose, uma doença caracterizada pelo acúmulo de placas contendo lipídeos na camada subendotelial de vasos sanguíneos. O glicocálice endotelial mantém a homeostasia entre o sangue e as células endoteliais e alterações em sua estrutura podem causar doenças. Algas marinhas são fontes de polissacarídeos sulfatados que apresentam diversas propriedades farmacológicas, entre as quais se destacam atividades antioxidante, anti-inflamatória, anticoagulante e antitrombótica. O objetivo deste trabalho foi avaliar os efeitos de uma ramnana sulfatada (RS) obtida da alga Monostroma nitidum em células endoteliais e musculares lisas, bem como em anéis de aorta, assim como, descrever seu provável mecanismo de ação. Foi constatado que RS não afeta a viabilidade dessas células em 24 horas na concentração de até 100 ?g/mL e é capaz de aumentar a marcação do glicocálice pela lectina WGA, observada em microscopia confocal, em ambas as linhagens celulares e também no anel de aorta de ratos. Há um aumento na síntese de ácido hialurônico por essas células tratadas com RS e esse ácido hialurônico apresenta alto peso molecular. Através da marcação metabólica com sulfato radioativo foi constatado que células tratadas com RS aumentaram a síntese de glicosaminoglicanos sulfatados com destaque para o heparam sulfato. Esse heparam sulfato teve sua estrutura analisada e foi observado que há um aumento na proporção de dissacarídeo trissulfatado, típico da estrutura de heparinas. Foi observado aumento na expressão das enzimas responsáveis pela síntese e modificação desses glicosaminoglicanos. Utilizando microscopia confocal e ensaio de FRET foi comprovado que RS se liga à fibronectina na matriz extracelular. RS ativa a sinalização celular através da via de FAK-Src-ERK, aumenta os níveis de cálcio intracelular e a produção de óxido nítrico. Por fim foi observado que RS também é capaz de inibir a angiogênese em ensaio de formação de estruturas capilares em matrigel e também no ensaio tridimensional de angiogênese em anel de aorta. Os resultados indicam que RS por aumentar e modificar estruturalmente o glicocálice nas células derivadas de aorta, estimular a síntese do heparam sulfato rico em dissacarídeo trisssulfatado (típico da estrutura de heparinas e com potente efeito antitrombótico), bem como de ácido hialurônico de alto peso molecular (com ação anti-aterogênica e antiangiogênica), aumentar a síntese de óxido nítrico e por si só inibir a angiogênese apresenta-se como um possível agente terapêutico para prevenir o desenvolvimento da aterosclerose e formação de trombos em função dos diversos efeitos benéficos nas células que podem impedir diferentes etapas desses processos patDados abertos - Sucupira - Teses e dissertações (2013 a 2016

Fucana ativa via das Map quinases e inibe a proliferação de células de ovário de hamster chinês (CHO)

Fucan is a term used to denominate L-fucose rich sulfated polysaccharides. The fucans have been studied due their pharmacological activities like antithrombotic, antiproliferative and antioxidant. We have extracted three fucan fractions from the brown seaweed Spatoglossum schröederi. These fucans were denominated Fuc B 1, Fuc B 1.5 and Fuc B 2. The chemical analyzes show that the fucans have very similar composition as demonstrated by agarose electrophoresis gel, sugar and sulfate content. The antiproliferative effect was determined by MTT and BrdU methodologies in CHO cells. The inhibition of proliferation effect of the three fractions was about 40%. Therefore this we proceed just with the Fuc B 2 due the higher yield. There is no apoptosis indication using the anexin V/propidium iodide test. We found a cell cycle phase G1 arrest. The western blotting show that the PKC; pFAK; pERK 1/2 are activated when the cells were treated with fucans. The treatement with inhibitor of MAPK PD98059 extinguished the fucan effect. These results indicates that fucan act by the ERK pathway inducing the cell death.Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorFucana é um termo utilizado para denominar polissacarídeos sulfatados ricos em L-Fucose. As fucanas têm sido estudadas devido suas atividades farmacológicas: antitrombótica, antiproliferativa e antioxidante. Nós extraímos três frações de fucanas da alga Spatoglossum schröederi. Essas fucanas, denominadas de Fuc B 1, Fuc B 1.5 e Fuc B 2, apresentam uma composição muito similar como demonstrado pela eletroforese em gel de agarose, e conteúdo de açúcar e sulfato. O efeito antiproliferativo foi determinado pelas metodologias de MTT e BrdU em células CHO. O efeito na inibição da proliferação das três frações foi de cerca de 40%. Assim, procedemos somente com a Fuc B 2 devido seu maior rendimento. Não houve indicação de apoptose usando a marcação com anexina V-FITC/ Iodeto de Propídeo. Identificamos uma parada na fase G1 do ciclo celular. Os ensaios de western blotting mostraram que PKC, pFAK e pERK 1/2 são ativadas quando as células são tratadas com Fuc B. O tratamento com o inibidor de MAPK PD98059 aboliu o efeito da fucana. Esses efeitos indicam que a fucana age via ERK para inibir a proliferação das células