26 research outputs found

    Electrospun Fibers in Composite Materials for Medical Applications

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    Sem PDF conforme Despacho. The authors acknowledge Portuguese Science and Technology Foundation (FCT-MCTES) for the financial support through the Strategic Project PEstC/CTM/LA0025/2013-14. Ana C. Baptista also acknowledges FCT-MCTES for the doctoral grant SFRH/BD/69306/2010.The development of nanoscaled materials has deserved a remarkable interest for biomedical applications. Biological tissues are essentially composite materials with particular mechanical properties that should be carefully considered during the design of innovative biomedical scaffolds. Electrospun membranes are often found in medical applications due to its high specific surface which creates a 3D porous structure that mimics the native extracellular matrix. These electrospun membranes can also be designed to have enhanced mechanical properties, biocompatibility and cellular response making them appealing and inspiring to be used in composites materials. This paper reviews the new insights in the development of advanced nanostructured composites materials based on electrospun fibers. From tissue engineering to bioelectronics, these composite materials can be found in the most promising research developments for the medical applications.publishersversionpublishe

    Cellulose-Based Bioelectronic Devices

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    The authors work was partially supported by Portuguese Science and Technology Foundation (FCT-MCTES) through the Strategic Project PEst-C/CTM/LA0025/2011. Ana Baptista also acknowledges FCT-MCTES for the doctoral grant SFRH/BD/69306/2010.publishersversionpublishe

    Biocomposite macrospheres based on strontium-bioactive glass for application as bone fillers

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    Traditional bioactive glass powders are typically composed of irregular particles that can be packed into dense configurations presenting low interconnectivity, which can limit bone ingrowth. The use of novel biocomposite sphere formulations comprising bioactive factors as bone fillers are most advantageous, as it simultaneously allows for packing the particles in a 3-dimensional manner to achieve an adequate interconnected porosity, enhanced biological performance, and ultimately a superior new bone formation. In this work, we develop and characterize novel biocomposite macrospheres of Sr-bioactive glass using sodium alginate, polylactic acid (PLA), and chitosan (CH) as encapsulating materials for finding applications as bone fillers. The biocomposite macrospheres that were obtained using PLA have a larger size distribution and higher porosity and an interconnectivity of 99.7%. Loose apatite particles were observed on the surface of macrospheres prepared with alginate and CH by means of soaking into a simulated body fluid (SBF) for 7 days. A dense apatite layer was formed on the biocomposite macrospheresâ surface produced with PLA, which served to protect PLA from degradation. In vitro investigations demonstrated that biocomposite macrospheres had minimal cytotoxic effects on a human osteosarcoma cell line (SaOS-2 cells). However, the accelerated degradation of PLA due to the degradation of bioactive glass may account for the observed decrease in SaOS-2 cells viability. Among the biocomposite macrospheres, those composed of PLA exhibited the most promising characteristics for their potential use as fillers in bone tissue repair applications.This work was funded by grant #2019/15960-6, São Paulo Research Foundation in Brazil (FAPESP) and the Portuguese Foundation for Science and Technology (FCT), Reference UID/CTM/50025/2019 and FCT/Minister of Science, Technology and Higher Education in Portugal (MCTES) and by European Regional Development Fund (FEDER) funds through the COMPETE 2020 Program in the framework of ORAiDEA project (ref n° 39985 - AAC 31/SI/2017). The authors would also like to acknowledge Materials Research Center (CENIMAT) of the Associated Laboratory Institute of Nanostructures, Nanomodeling and Nanofabrication (i3N), NOVA University of LisbonCENIMAT|i3N and National Council for Scientific and Technological Development in Brazil CNPq (303149/2018-3). Ibrahim Fatih Cengiz acknowledges the FCT distinction attributed to him under the “Estímulo ao Emprego Científico” program (2021.01969.CEECIND). The authors thank the financial support provided under the projects: “HEALTH-UNORTE: Setting-up biobanks and regenerative medicine strategies to boost research in cardiovascular, musculoskeletal, neurological, oncological, immunological, and infectious diseases”, reference NORTE-01-0145-FEDER-000039, funded by the Norte Portugal Regional Coordination and Development Commission (CCDR-N), under the NORTE2020 Program; Projects LA/P/0037/2020, UIDP/50025/2020, and UIDB/50025/ 2020 of the Associate Laboratory i3N financed by national funds from FCT

    Transfusion practices in brazilian Intensive Care Units (pelo FUNDO-AMIB)

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    BACKGROUND AND OBJECTIVES: Anemia of critical illness is a multifactorial condition caused by blood loss, frequent phlebotomies and inadequate production of red blood cells (RBC). Controversy surrounds the most appropriate hemoglobin concentration trigger for transfusion of RBC. We aimed to evaluate transfusion practices in Brazilian ICUs. METHODS: A prospective study throughout a 2-week period in 19 Brazilian ICUs. Hemoglobin (Hb) level, transfusion rate, organ dysfunction assessment and 28-day mortality were evaluated. Primary indication for transfusion and pretransfusion hemoglobin level were collected for each transfusion. RESULTS: Two hundred thirty-one patients with an ICU length of stay longer than 48h were included. An Hb level lower than 10 g/dL was found in 33% on admission in the ICU. A total of 348 RBC units were transfused in 86 patients (36.5%). The mean pretransfusion hemoglobin level was 7.7 ± 1.1 g/dL. Transfused-patients had significantly higher SOFA score (7.9 ± 4.6 vs 5.6 ± 3.8, p < 0.05, respectively), days on mechanical ventilation (10.7 ± 8.2 vs 7.2 ± 6.4, p < 0.05) and days on vasoactive drugs (6.7 ± 6.4 vs 4.2 ± 4.0, p < 0.05) than non-transfused patients despite similar APACHE II scores (15.2 ± 8.1 vs 14.2 ± 8.1, NS). Transfused patients had higher mortality rate (43.5%) than non-transfused patients (36.3%) (RR 0.60-1.15, NS). Only one patient (0.28%) had febrile non-hemolytic transfusion and urticarial reactions. CONCLUSIONS: Anemia is common in critically ill patients.It seems from the present study that transfusion practices in Brazil have had a more restrictive approach with a lower limit transfusion trigger.JUSTIFICATIVA E OBJETIVOS: A anemia é uma condição comum em pacientes graves. A transfusão de hemoderivados aumenta de forma significativa o risco de transmissão de agentes infecciosos e afeta o perfil imunológico. O objetivo deste estudo foi avaliar a incidência de anemia e a prática de transfusão de hemácias em UTI brasileiras. MÉTODO: Estudo prospectivo, multicêntrico, realizado em 19 UTI em um período de duas semanas. A presença de anemia, as indicações e a utilização de concentrados de hemácias, foram avaliadas diariamente. As complicações que ocorreram durante a internação na UTI e após a transfusão da primeira unidade de concentrado de hemácias foram registradas. RESULTADOS: Um total de 33% apresentava anemia na admissão na UTI e esta proporção aumentou para 55% no final de sete dias de internação. Um total de 348 unidades de concentrado de hemácias foi transfundido em 86 pacientes (36,5%). A média de suas unidades por paciente foi 4,1 ± 3,3 U. O nível de hemoglobina limiar para a transfusão de CH foi 7,7 ± 1,1 g/dL. Pacientes transfundidos tinham mais disfunções orgânicas avaliadas pelo escore SOFA (7,9 ± 4,6 versus 5,6 ± 3,8, transfundidos versus não transfundidos, p < 0,05). As taxas de mortalidade foram 43,5% e 36,3% em pacientes transfundidos e não transfundidos, respectivamente (RR 0,61-11,7, NS). Pacientes transfundidos tiveram número maior de complicações (1,58 ± 0,66 versus 1,33 ± 0,49, p = 0,0001). CONCLUSÕES: A anemia é comum em UTI brasileiras. O limiar transfusional de hemoglobina foi menor do que o observado em outros paises.Faculdade de Medicina de São José do Rio PretoUniversidade de São PauloUFRGS Departamento de Medicina Interna HC de Porto AlegreUniversidade Paris VIUFRJ CTI dos Hospitais Cardiotrauma Ipanema e São LucasAMIBUniversidade Estadual de LondrinaUFRGS FAMED HCPAFaculdade de Medicina de CatanduvaUNIFESP-EPMFundação Padre Albino UTI do Complexo HospitalarUniversidade Federal de São Paulo (UNIFESP) Disciplina de Anestesiologia, Dor e Terapia Intensiva Setor de TerapiaSanta Casa de Misericórdia de São PauloHospital Unimed de LimeiraUTI do Hospital Regional de AssisAMIB Departamento de MedicinaAmerican CollegeFundação Getúlio VargasHospital Pró CardíacoUNIRIOFGVHospital Santa Helena de GoiâniaHospital evangélico de Cachoeiro de Itapemirim Unidade coronarianaSBNHospital Evangélico Cachoeiro de Itapemirim UTI Adulto e CoronarianaUFRJUFRN Hospital Onofre Lopes UTIHospital Novo AtibaiaUNIFESP, EPMUNIFESP, Disciplina de Anestesiologia, Dor e Terapia Intensiva Setor de TerapiaSciEL

    COMPARAÇÃO ENTRE APENDICECTOMIA ABERTA E LAPAROSCÓPICA

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    Appendectomy, the surgical removal of the inflamed appendix, is a common procedure performed to treat acute appendicitis, one of the most common surgical emergencies. Over the years, two main approaches have been used: open appendectomy, which is the traditional technique, and laparoscopic appendectomy, a minimally invasive approach that has gained popularity in recent decades. The choice between these surgical techniques is a topic of ongoing debate in the medical community, with considerations regarding the benefits and risks of each approach. Objective: To compare clinical outcomes, postoperative complications, recovery time and costs associated with open and laparoscopic appendectomy. Methodology: The Pubmed, Scielo and Medline databases were used, searching for articles published between 2022 and 2024, in Portuguese or English. Final Considerations: In conclusion, the data analyzed indicate that laparoscopic appendectomy offers advantages over the open approach, including less postoperative pain, shorter hospital stay, faster recovery and lower incidence of complications.A apendicectomia, a remoção cirúrgica do apêndice inflamado, é um procedimento comum realizado para tratar a apendicite aguda, uma das emergências cirúrgicas mais comuns. Ao longo dos anos, duas abordagens principais têm sido utilizadas: a apendicectomia aberta, que é a técnica tradicional, e a apendicectomia laparoscópica, uma abordagem minimamente invasiva que ganhou popularidade nas últimas décadas. A escolha entre essas técnicas cirúrgicas é um tema de debate contínuo na comunidade médica, com considerações sobre os benefícios e os riscos de cada abordagem. Objetivo: Comparar os resultados clínicos, as complicações pós-operatórias, o tempo de recuperação e os custos associados à apendicectomia aberta e laparoscópica. Metodologia:&nbsp; Foram utilizadas as bases de dados Pubmed, Scielo e Medline, buscando artigos publicados entre os anos de 2022 e 2024, nos idiomas Português ou Inglês. Considerações Finais: Em conclusão, os dados analisados indicam que a apendicectomia laparoscópica oferece vantagens sobre a abordagem aberta, incluindo menor dor pós-operatória, tempo de internação mais curto, recuperação mais rápida e menor incidência de complicações

    Pervasive gaps in Amazonian ecological research

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    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

    Pervasive gaps in Amazonian ecological research

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    Pervasive gaps in Amazonian ecological research

    Get PDF
    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

    Get PDF
    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

    Catálogo Taxonômico da Fauna do Brasil: setting the baseline knowledge on the animal diversity in Brazil

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    The limited temporal completeness and taxonomic accuracy of species lists, made available in a traditional manner in scientific publications, has always represented a problem. These lists are invariably limited to a few taxonomic groups and do not represent up-to-date knowledge of all species and classifications. In this context, the Brazilian megadiverse fauna is no exception, and the Catálogo Taxonômico da Fauna do Brasil (CTFB) (http://fauna.jbrj.gov.br/), made public in 2015, represents a database on biodiversity anchored on a list of valid and expertly recognized scientific names of animals in Brazil. The CTFB is updated in near real time by a team of more than 800 specialists. By January 1, 2024, the CTFB compiled 133,691 nominal species, with 125,138 that were considered valid. Most of the valid species were arthropods (82.3%, with more than 102,000 species) and chordates (7.69%, with over 11,000 species). These taxa were followed by a cluster composed of Mollusca (3,567 species), Platyhelminthes (2,292 species), Annelida (1,833 species), and Nematoda (1,447 species). All remaining groups had less than 1,000 species reported in Brazil, with Cnidaria (831 species), Porifera (628 species), Rotifera (606 species), and Bryozoa (520 species) representing those with more than 500 species. Analysis of the CTFB database can facilitate and direct efforts towards the discovery of new species in Brazil, but it is also fundamental in providing the best available list of valid nominal species to users, including those in science, health, conservation efforts, and any initiative involving animals. The importance of the CTFB is evidenced by the elevated number of citations in the scientific literature in diverse areas of biology, law, anthropology, education, forensic science, and veterinary science, among others
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