Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 88
Filtrar
1.
Porto Alegre; Editora Rede Unida; abr. 2024. 353 p.
Monografia em Português | LILACS | ID: biblio-1554977

RESUMO

O livro "Amazônia solidária: educação popular e comunicação em saúde para o fortalecimento da vacinação nos territórios quilombolas, migrantes e ribeirinhos" é produto do projeto Amazônia Solidário que teve como objetivo reforçar as estratégias de comunicação sobre a vacina de Covid-19 e outras. O caminho utilizado foi da Educação Permanente nos territórios do Amazonas e do Acre, construindo COM as comunidades e grupos os modos e as linguagens da comunicação de uma política tão maltratada na última gestão governamental. Vimos a potência criativa das comunidades que simplesmente precisou ser ouvida e apoiada na construção dos seus materiais. O projeto nos permitiu amazonizar o pensamento e as estratégias da saúde, significando um estar nos territórios ribeirinhos, quilombolas e dos migrantes na cidade como um modo de refletir sobre uma dimensão diferente da vida. O encontro com outros, com modos diferentes de ser e estar no mundo, numa outra relação entre os humanos e não humanos, na relação com o território das águas e da cidade, nos traz outras formas de viver na Amazônia. Os encontros nos territórios das pessoas, que vivem as relações com as águas, com as memórias, com os encantados, com a ancestralidade, nos fazem perceber que o ser e estar ultrapassa a lógica da subsistência do "viver melhor" e não do "viver bem". Desse modo, desejamos que esse caminho, das águas, das estradas, das trilhas, possa ser fonte inspiradora da gestão das políticas públicas.


Assuntos
Humanos , Masculino , Feminino , Gravidez , Recém-Nascido , Lactente , Pré-Escolar , Criança , Adolescente , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Adulto Jovem
2.
Nat Commun ; 15(1): 1837, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38418815

RESUMO

Latin America and Caribbean (LAC) regions were an important epicenter of the COVID-19 pandemic and SARS-CoV-2 evolution. Through the COVID-19 Genomic Surveillance Regional Network (COVIGEN), LAC countries produced an important number of genomic sequencing data that made possible an enhanced SARS-CoV-2 genomic surveillance capacity in the Americas, paving the way for characterization of emerging variants and helping to guide the public health response. In this study we analyzed approximately 300,000 SARS-CoV-2 sequences generated between February 2020 and March 2022 by multiple genomic surveillance efforts in LAC and reconstructed the diffusion patterns of the main variants of concern (VOCs) and of interest (VOIs) possibly originated in the Region. Our phylogenetic analysis revealed that the spread of variants Gamma, Lambda and Mu reflects human mobility patterns due to variations of international air passenger transportation and gradual lifting of social distance measures previously implemented in countries. Our results highlight the potential of genetic data to reconstruct viral spread and unveil preferential routes of viral migrations that are shaped by human mobility patterns.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , América Latina/epidemiologia , Pandemias , Filogenia , COVID-19/epidemiologia , Região do Caribe/epidemiologia
3.
ACS Appl Mater Interfaces ; 15(40): 46747-46755, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37782693

RESUMO

Point-of-care (POC) devices can provide inexpensive, practical, and expedited solutions for applications ranging from biomedicine to environmental monitoring. This work reports on the development of low-cost microfluidic substrates for POC systems suitable for analytical assays, while also satisfying the need for social and environmentally conscious practices regarding circular economy, waste reduction, and the use of local resources. Thus, an innovative greener process to extract cellulose from plants including abaca, cotton, kozo, linen, and sisal, originating from different places around the world, is developed, and then the corresponding paper substrates are obtained to serve as platforms for POC assays. Hydrophobic wax is used to delineate channels that are able to guide solutions into chambers where the colorimetric assay for total cholesterol quantification is carried out as a proof of concept. Morphological and physicochemical analyses are performed, including the evaluation of fiber diameter, shape and density, and mechanical and thermal properties, together with peel adhesion of the printed wax channels. Contact angle and capillary flow tests ascertain the suitability of the substrates for liquid assays and overall viability as low-cost, sustainable microfluidic substrates for POC applications.


Assuntos
Técnicas Analíticas Microfluídicas , Papel , Colorimetria , Floresta Úmida , Celulose , Bioensaio , Sistemas Automatizados de Assistência Junto ao Leito , Dispositivos Lab-On-A-Chip
4.
Chem Rev ; 123(19): 11392-11487, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37729110

RESUMO

From scientific and technological points of view, poly(vinylidene fluoride), PVDF, is one of the most exciting polymers due to its overall physicochemical characteristics. This polymer can crystalize into five crystalline phases and can be processed in the form of films, fibers, membranes, and specific microstructures, being the physical properties controllable over a wide range through appropriate chemical modifications. Moreover, PVDF-based materials are characterized by excellent chemical, mechanical, thermal, and radiation resistance, and for their outstanding electroactive properties, including high dielectric, piezoelectric, pyroelectric, and ferroelectric response, being the best among polymer systems and thus noteworthy for an increasing number of technologies. This review summarizes and critically discusses the latest advances in PVDF and its copolymers, composites, and blends, including their main characteristics and processability, together with their tailorability and implementation in areas including sensors, actuators, energy harvesting and storage devices, environmental membranes, microfluidic, tissue engineering, and antimicrobial applications. The main conclusions, challenges and future trends concerning materials and application areas are also presented.

5.
ACS Sens ; 8(8): 3032-3042, 2023 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-37467113

RESUMO

Health initiatives worldwide demand affordable point-of-care devices to aid in the reduction of morbidity and mortality rates of high-incidence infectious and noncommunicable diseases. However, the production of robust and reliable easy-to-use diagnostic platforms showing the ability to quantitatively measure several biomarkers in physiological fluids and that could in turn be decentralized to reach any relevant environment remains a challenge. Here, we show the particular combination of paper-microfluidic technology, electrochemical transduction, and magnetic nanoparticle-based immunoassay approaches to produce a unique, compact, and easily deployable multiplex device to simultaneously measure interleukin-8, tumor necrosis factor-α, and myeloperoxidase biomarkers in sputum, developed with the aim of facilitating the timely detection of acute exacerbations of chronic obstructive pulmonary disease. The device incorporates an on-chip electrochemical cell array and a multichannel paper component, engineered to be easily aligned into a polymeric cartridge and exchanged if necessary. Calibration curves at clinically relevant biomarker concentration ranges are produced in buffer and artificial sputum. The analysis of sputum samples of healthy individuals and acutely exacerbated patients produces statistically significant biomarker concentration differences between the two studied groups. The device can be mass-produced at a low cost, being an easily adaptable platform for measuring other disease-related target biomarkers.


Assuntos
Microfluídica , Nanopartículas , Humanos , Escarro , Sistemas Automatizados de Assistência Junto ao Leito , Biomarcadores/análise
6.
Int J Dent ; 2023: 9929835, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37159593

RESUMO

Purpose: The aim of this study was to compare clinical periodontal conditions in HIV-positive people on HAART with an HIV-negative group, in addition to investigating factors associated with periodontitis in the entire sample. Methods: This was a cross-sectional study. Data were collected by oral clinical examination for the diagnosis of periodontitis, review of medical records, and application of a questionnaire containing personal data, deleterious habits, and oral hygiene habits for the other variables. The results were analyzed by Pearson's χ 2 test and Student's t-test. A logistic regression model was constructed for the multivariate analysis and periodontitis was defined as a dependent variable. The analysis was performed on the entire sample (HIV+ and HIV-) and also on the group consisting of only people living with HIV. Results: Individuals older than 43 years old and with HIV were more likely to develop moderate and severe periodontitis (47.80 and 4.84 times, respectively). When analyzing only HIV+, in addition to age (OR = 2.795; CI = 1.080-7.233), the use of nonnucleoside reverse transcriptase inhibitors (NNRTIs) (OR = 2.841; CI = 1.135-7.112) was also associated with moderate and severe periodontitis. Conclusion: It was possible to observe a higher prevalence of periodontitis among individuals with HIV, showing an association between the virus, advanced age, and moderate or severe periodontitis.

7.
Biomater Adv ; 151: 213438, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37121084

RESUMO

The physico-chemical properties of the scaffold materials used for tissue regeneration strategies have a direct impact on cell shape, adhesion, proliferation, phenotypic and differentiation. Herewith, biophysical and biochemical cues have been widely used to design and develop biomaterial systems for specific tissue engineering strategies. In this context, the patterning of piezoelectric polymers that can provide electroactive stimuli represents a suitable strategy for skeletal muscle tissue engineering applications once it has been demonstrated that mechanoelectrical stimuli promote C2C12 myoblast differentiation. In this sense, this works reports on how C2C12 myoblast cells detect and react to physical and biochemical stimuli based on micropatterned poly(vinylidene fluoride-co-trifluoroethylene) (P(VDF-TrFE)) electroactive scaffolds produced by soft lithography in the form of arrays of lines and hexagons (anisotropic and isotropic morphology, respectively) combined with differentiation medium. The scaffolds were evaluated for the proliferation and differentiation of C2C12 myoblast cell line and it is demonstrated that anisotropic microstructures promote muscle differentiation which is further reinforced with the introduction of biochemical stimulus. However, when the physical stimulus is not adequate to the tissue, e.g. isotropic microstructure, the biochemical stimulus has the opposite effect, hindering the differentiation process. Therefore, the proper morphological design of the scaffold combined with biochemical stimulus allows to enhance skeletal muscle differentiation and allows the development of advanced strategies for effective muscle tissue engineering.


Assuntos
Materiais Biocompatíveis , Alicerces Teciduais , Alicerces Teciduais/química , Diferenciação Celular/fisiologia , Engenharia Tecidual , Mioblastos/metabolismo
8.
Adv Healthc Mater ; 12(18): e2202936, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36898671

RESUMO

The clinical translations of drugs and nanomedicines depend on coherent pharmaceutical research based on biologically accurate screening approaches. Since establishing the 2D in vitro cell culture method, the scientific community has improved cell-based drug screening assays and models. Those advances result in more informative biochemical assays and the development of 3D multicellular models to describe the biological complexity better and enhance the simulation of the in vivo microenvironment. Despite the overall dominance of conventional 2D and 3D cell macroscopic culture methods, they present physicochemical and operational challenges that impair the scale-up of drug screening by not allowing a high parallelization, multidrug combination, and high-throughput screening. Their combination and complementarity with microfluidic platforms enable the development of microfluidics-based cell culture platforms with unequivocal advantages in drug screening and cell therapies. Thus, this review presents an updated and consolidated view of cell culture miniaturization's physical, chemical, and operational considerations in the pharmaceutical research scenario. It clarifies advances in the field using gradient-based microfluidics, droplet-based microfluidics, printed-based microfluidics, digital-based microfluidics, SlipChip, and paper-based microfluidics. Finally, it presents a comparative analysis of the performance of cell-based methods in life research and development to achieve increased precision in the drug screening process.


Assuntos
Ensaios de Triagem em Larga Escala , Microfluídica , Microfluídica/métodos , Avaliação Pré-Clínica de Medicamentos/métodos , Ensaios de Triagem em Larga Escala/métodos , Terapia Baseada em Transplante de Células e Tecidos , Técnicas de Cultura de Células
9.
Artigo em Espanhol, Português | LILACS | ID: biblio-1417801

RESUMO

OBJETIVO: A partir do nascimento pré-termo, a maternidade é convocada prematuramente, pois o tempo final da gestação não pode ser vivido e o que foi idealizado não se concretiza. Dessa forma, a mulher mãe precisa ressignificar seu papel e a própria maternidade, reestruturando seu sistema cuidador para dar conta da situação real que se apresenta. O nascimento prematuro insere muitas dificuldades para a mulher, influenciando em momentos estressantes e deflagrando sentimentos de frustação, culpa, ansiedade, tristeza, medo, entre outros. OBJETIVO: Compreender as dificuldades, emoções e sentimentos presentes durante o nascimento e hospitalização dos recém-nascidos pré-termos extremos e como a(s) maternidade(s) puderam ir se construindo nesse contexto. MÉTODO: Estudo qualitativo, com coleta de narrativas de mulheres que compartilharam suas experiências em um site especializado na internet. A análise foi realizada a partir da Análise de Conteúdo, utilizando como embasamento teórico a teoria do apego. RESULTADOS: As narrativas retratam uma alta expectativa em relação ao nascimento dos bebês, bem como a frustração e angústia geradas a partir da necessidade de uma separação brusca e literal. Ainda, os momentos foram marcados por uma rotina exaustiva e pelo medo do bebê vir a óbito, além da necessidade de aprenderem a reconhecer os sinais sutis dos bebês e construir modos de cuidados possíveis. As narrativas trabalhadas foram/são uma maneira que elas encontraram para relatar suas histórias e de ressignificar o vivido. CONSIDERAÇÕES FINAIS: Destaca-se a importância de haver o reconhecimento das vivências maternas nesse contexto para que melhorias no acolhimento prestado e construção de políticas públicas sejam possíveis de serem realizadas.


OBJECTIVE: From preterm birth, motherhood is called prematurely, as the final period of pregnancy cannot be lived and what was idealized does not come true. Thus, the mother-woman needs to reformulate her role and her own motherhood, restructuring her care system to account for the real situation that is presented. Premature birth entails many difficulties for women, influencing stressful moments and triggering feelings of frustration, guilt, anxiety, sadness, and fear, among others. OBJECTIVE: Understand the difficulties, emotions, and feelings present during the birth and hospitalization of extreme preterm newborns and how motherhood could be built in this context. METHODS: Qualitative study, collecting narratives from women who shared their experiences on a specialized website on the internet. The analysis was carried out from the Content Analysis, using the attachment theory as the theoretical basis. RESULTS: The results point to a high expectation in relation to the birth of babies, as well as the frustration and anguish generated by the need for a sudden and literal separation. The moments were marked by an exhaustive routine and by the fear of the baby dying, in addition to the need to learn to recognize the subtle signs of the babies and build possible care modes. The narratives worked on were a way they found to report their stories and redefine what they had lived. CLOSING REMARKS: The importance of recognizing maternal experiences in this context is highlighted so that improvements in the reception provided and the construction of public policies are possible to be carried out.


OBJETIVO: Desde el parto prematuro, la maternidad es convocada prematuramente, ya que el período final del embarazo no se puede vivir y lo idealizado no se hace realidad. Por lo tanto, la madre necesita replantear su rol y maternidad, reestructurar su sistema de cuidado para dar cuenta de la situación real que se presenta. El parto prematuro conlleva muchas dificultades para la mujer, influyendo en momentos estresantes y desencadenando sentimientos de frustración, culpa, ansiedad, tristeza, miedo, entre otros. OBJETIVO: Comprender las dificultades, emociones y sentimientos presentes durante el parto y la hospitalización de recién nacidos prematuros extremos y cómo la(s) maternidad(es) podría(n) ser construida(s) en ese contexto. MÉTODO: Estudio cualitativo, con la recopilación de relatos de mujeres que compartieron sus experiencias en un sitio web especializado en internet. El análisis se realizó con base en el Análisis de Contenido, utilizando como base teórica la teoría del apego. RESULTADOS: Apuntaron a una alta expectativa en relación al nacimiento de bebés, así como a la frustración y angustia que genera la necesidad de una separación repentina y literal. Aún así, los momentos estuvieron marcados por una rutina exhaustiva y por el miedo a la muerte del bebé, además de la necesidad de aprender a reconocer los signos sutiles de los bebés y construir posibles modos de cuidado. Las narrativas trabajadas fueron/son una forma que apoyan para relatar sus historias y para resignificar la experiencia. CONSIDERACIONES FINALES: Se resalta la importancia de reconocer las experiencias maternas en este contexto, para que se puedan llevar a cabo mejoras en la atención brindada y la construcción de políticas públicas.


Assuntos
Poder Familiar , Recém-Nascido Prematuro , Mães
10.
Fisioter. Mov. (Online) ; 36: e36124, 2023. tab
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1448251

RESUMO

Abstract Introduction Return to sport is a desired outcome in individuals submitted to anterior cruciate ligament reconstruction (ACLR). Objective Understand the factors that affect return to pre-injury level sport after ACLR from the patient's perspective. Methods The sample consisted of 29 individuals submitted to ACLR who participated in sport before the ligament injury. This is a narrative analysis with a qualitative approach, using a semi-structured interview as a methodological resource. Standardized instruments were also applied to evaluate psychological readiness to return to sport, via the Anterior Cruciate Ligament - Return to Sport after Injury Scale (ACL-RSI); self-perceived knee function using the International Knee Documentation Committee (IKDC) subjective questionnaire; and the frequency of participation in sports with the Marx scale. Results Analysis of the interviews produced three main themes related to post-ACLR return to sport: self-discipline, fear of reinjury and social support. In qualitative analysis, the average scores obtained were 59.17 (± 23.22) on the ACL-RSI scale, 78.16 (± 19.03) for the IKDC questionnaire and 9.62 (± 4.73) and 7.86 (± 5.44) for the Marx scale before and after surgery, respectively. Conclusion: Psychological factors influence the decision to return to sport post-ACLR. Physiotherapists should therefore be aware of the psychological aspects and expectations of patients, and that other health professionals may be needed to help prepare these individuals to return to their preinjury sports level and achieve more satisfactory outcomes after ACLR.


Resumo Introdução O retorno ao esporte é um desfecho alme-jado pelos indivíduos que se submetem à reconstrução do ligamento cruzado anterior (RLCA). Objetivo Com-preender os fatores que interferem no retorno ao esporte no nível anterior à lesão ligamentar em indivíduos submetidos à RLCA sob o ponto de vista do paciente. Métodos A amostra foi composta por 29 indivíduos que se submeteram à RLCA e praticavam esporte antes da lesão ligamentar. O estudo é caracterizado como uma pesquisa narrativa de abordagem qualitativa, utilizando como recurso metodológico a entrevista semiestrutu-rada. Com o uso de instrumentos padronizados, avaliou-se também a prontidão psicológica para retornar ao esporte, utilizando a escala ACL-RSI; a autopercepção da função do joelho, utilizando o questionário subjetivo do IKDC; e a frequência de participação esportiva antes da lesão e após a cirurgia, utilizando a Escala de Marx. Resultados A análise das entrevistas gerou três unidades temáticas principais relacionadas com o retorno ao esporte pós-RLCA: autodisciplina, medo de uma nova lesão e suporte social. Na análise quantitativa, obteve-se média de 59,17 pontos (± 23,22) na escala ACL-RSI, 78,16 pontos (± 19,03) no IKDC, e 9,62 (± 4,73) e 7,86 pontos (± 5,44) na escala de Marx, antes da lesão e após a cirurgia, respectivamente. Conclusão Fatores psicológicos influenciam a decisão de retorno ao esporte pós-RLCA. Os fisioterapeutas, portanto, devem estar atentos aos aspectos psicológicos e expectativas dos pacientes, considerando a necessidade de outros profissionais da saúde auxiliarem na preparação do indivíduo para retornar ao nível esportivo pré-lesão e alcançar resultados mais satisfatórios pós-RLCA.

11.
Barbarói ; (62): 217-240, jul.-dez. 2022.
Artigo em Português | LILACS, INDEXPSI | ID: biblio-1418752

RESUMO

Esse artigo formaliza em conceitos e linhas de arguição articuladas sobre eventos do nosso cotidiano contemporâneo. Produzimos, por meio de uma narrativa-ficção, sobre os engendramentos existentes entre as lógicas do empreendedorismo, do crime e da religiosidade em seus atravessamentos pelos dispositivos necropolíticos-coloniais. A ficção operou tal análise com uma redução ao absurdo: colapsando as lógicas que buscam cindir o mundo entre "vagabundos" e "trabalhadores" ou "criminosos" e "cidadão de bem". O racismo estrutural e o estigma da periculosidade criam a figura do "vagabundo" como par oposto ao trabalhador, por uma sobreposição de camadas discursivas e imagéticas que criminaliza, encarcera e extermina juventudes negras periféricas em nome da manutenção dos privilégios da branquitude. O sistema penal brasileiro é racista e classista, perpetuando a lógica moderno-colonial que passa a fazer parte da elaboração das políticas de segurança pública. Questionamos essa racionalidade, compreendendo que o crime organizado não funciona fora da lógica neoliberal, da moral empreendedora e conservadora vigente. A redução ao absurdo nos ajuda a olhar de outra forma para as noções de culpa, mérito e para a própria noção de trabalho, levando-as aos seus limites, transgredindo as fronteiras jurídicas, para visibilizar que ambos comungam de uma rede de valores coloniais: agressividade competitiva, disciplina, obediência à hierarquia e elevação moral. Nesse paradoxo, entre a moral do crime organizado e da moralidade conservadora, visibilizamos elementos fundamentais da máquina de subjetivação do nosso tempo.(AU)


This article formalizes in articulate concepts and lines of argument about events in our contemporary everyday life. We have produced, through a narrative-fiction, about the existing engagements between the logics of entrepreneurship, crime, and religiosity in their intersections by necropolitical-colonial mechanisms. The fiction has performed this analysis with a reduction to the absurd: collapsing the logic that seeks to split the world between " tramps" and "workers" or " thugs" and "good citizens". The structural racism and the stigma of dangerousness create the figure of the " tramp" as an opposite pair to the worker, by an overlapping of discursive and imagetic layers that criminalizes, incarcerates, and exterminates suburban black youths in the name of the preservation of the privileges of whiteness. The criminal justice system in Brazil is racist and classist, perpetuating the modern-colonial approach that becomes part of the development of public security policies. We have questioned this rationality, understanding that organized crime does not function outside the neoliberal mindset, the entrepreneurial and conservative current morals. The reduction to absurd helps us to look in another way to the notions of guilt, merit and the concept of work, taking them to its limits, transgressing legal boundaries, to make visible that both share a network of colonial moral values: competitive aggressiveness, discipline, obedience to hierarchy and moral superiority. In this paradox, between the morality of the crime organized and conservational morality, we make visible fundamental elements of the machine of subjectivation of our time.(AU)


Este artículo se formaliza en conceptos y líneas argumentales articuladas sobre acontecimientos de nuestra vida cotidiana contemporánea. Producimos, a partir de una narración-ficción, acerca de los engendros existentes entre las lógicas del emprendimiento, el crimen y la religiosidad en sus entrecruzamientos por los aparatos de la necropolítica-colonial. La ficción operó ese análisis con una reducción al absurdo: desmoronando las lógicas que pretenden dividir el mundo entre " los vagos " y " los trabajadores " o " los criminales " y " los buenos ciudadanos ". El racismo estructural y el estigma de la peligrosidad crean la figura del "vago" como par opuesto al trabajador, a partir de una superposición de estratos discursivos e iconográficos que criminaliza, aprisiona y extermina a la juventud negra de la periferia en nombre del mantenimiento de los privilegios de la blancura.El sistema de justicia penal brasileño es racista y clasista, perpetuando la lógica moderno-colonial que se integra en la elaboración de las políticas de seguridad publica. Nosotros cuestionamos esta racionalidad, comprendiendo que el crimen organizado no funciona al margen de la lógica del neoliberalismo, de la moral empresarial y conservadora vigente. La reducción al absurdo nos ayuda a mirar de otra manera las nociones de culpa, mérito y la propia noción de trabajo, llevándolas a sus límites, transgrediendo las fronteras legales, para hacer visible que ambas comparten una trama de valores coloniales: agresividad competitiva, disciplina, obediencia a la jerarquía y elevación moral. En esta paradoja, entre la moral del crimen organizado y la moral conservadora, se hacen visibles elementos fundamentales de la máquina de subjetivación de nuestro tiempo.(AU)


Assuntos
Humanos , Prisões , Religião , Trabalho , Empreendedorismo , Sistema de Justiça , Racismo Sistêmico , Crime , Capitalismo
12.
Biomedicines ; 10(5)2022 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-35625942

RESUMO

Stimuli-responsive liposomes are a class of nanocarriers whose drug release occurs, preferentially, when exposed to a specific biological environment, to an external stimulus, or both. This work is focused on the design of solid magnetoliposomes (SMLs) as lipid-based nanosystems aiming to obtain multi-stimuli-responsive vesicles for doxorubicin (DOX) controlled release in pathological areas under the action of thermal, magnetic, and pH stimuli. The effect of lipid combinations on structural, colloidal stability, and thermodynamic parameters were evaluated. The results confirmed the reproducibility for SMLs synthesis based on nine lipid formulations (combining DPPC, DSPC, CHEMS, DOPE and/or DSPE-PEG), with structural and colloidal properties suitable for biological applications. A loss of stability and thermosensitivity was observed for formulations containing dioleoylphosphatidylethanolamine (DOPE) lipid. SMLs PEGylation is an essential step to enhance both their long-term storage stability and stealth properties. DOX encapsulation (encapsulation efficiency ranging between 87% and 96%) in the bilayers lowered its pKa, which favors the displacement of DOX from the acyl chains to the surface when changing from alkaline to acidic pH. The release profiles demonstrated a preferential release at acidic pH, more pronounced under mimetic mild-hyperthermia conditions (42 °C). Release kinetics varied with the lipid formulation, generally demonstrating hyperthermia temperatures and acidic pH as determining factors in DOX release; PEGylation was shown to act as a diffusion barrier on the SMLs surface. The integrated assessment and characterization of SMLs allows tuning lipid formulations that best respond to the needs for specific controlled release profiles of stimuli-responsive nanosystems as a multi-functional approach to cancer targeting and therapy.

13.
Lab Chip ; 22(10): 1876-1889, 2022 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-35485913

RESUMO

Diabetic retinopathy (DR) is the most common diabetic eye disease and the worldwide leading cause of vision loss in working-age adults. It progresses from mild to severe non-proliferative or proliferative DR based on several pathological features including the magnitude of blood-retinal barrier breakdown and neovascularization. Available pharmacological and retinal laser photocoagulation interventions are mostly applied in the advanced stages of DR and are inefficient in halting disease progression in a significantly high percentage of patients. Yet, recent evidence has shown that some therapies could potentially limit DR progression if applied at early stages, highlighting the importance of early disease diagnostics. In the past few decades, different imaging modalities have proved their utility for examining retinal and optic nerve changes in patients with retinal diseases. However, imaging based-methodologies solely rely on morphological examination of the retinal vascularization and are not suitable for recurrent and personalized patient evaluation. This raises the need for new technologies to enable accurate and early diagnosis of DR. In this review, we critically discuss the potential clinical benefit of minimally-invasive molecular biomarker identification and profiling of diabetic patients who are at risk of developing DR. We provide a comparative overview of conventional and recently developed lab-on-a-chip technologies for quantitative assessment of potential DR molecular biomarkers and discuss their advantages, current limitations and challenges for future practical implementation and continuous patient monitoring at the point-of-care.


Assuntos
Diabetes Mellitus , Retinopatia Diabética , Adulto , Retinopatia Diabética/diagnóstico por imagem , Humanos , Dispositivos Lab-On-A-Chip , Retina
14.
iScience ; 25(4): 104156, 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35368908

RESUMO

The COVID-19 epidemic in Brazil experienced two major lineage replacements until mid-2021. The first was driven by lineage P.2, in late 2020, and the second by lineage Gamma, in early 2021. To understand how these SARS-CoV-2 lineages spread in Brazil, we analyzed 11,724 genomes collected throughout the country between September 2020 and April 2021. Our findings indicate that lineage P.2 probably emerged in July 2020 in the Rio de Janeiro state and Gamma in November 2020 in the Amazonas state. Both states were the main hubs of viral disseminations to other Brazilian locations. We estimate that Gamma was 1.56-3.06 times more transmissible than P.2 in Rio de Janeiro and that the median effective reproductive number (Re) of Gamma varied according to the geographic context (Re = 1.59-3.55). In summary, our findings support that lineage Gamma was more transmissible and spread faster than P.2 in Brazil.

15.
ACS Appl Mater Interfaces ; 14(11): 13013-13024, 2022 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-35282678

RESUMO

Biomimicking biological niches of healthy tissues or tumors can be achieved by means of artificial microenvironments, where structural and mechanical properties are crucial parameters to promote tissue formation and recreate natural conditions. In this work, three-dimensional (3D) scaffolds based on woodpile structures were fabricated by two-photon polymerization (2PP) of different photosensitive polymers (IP-S and SZ2080) and hydrogels (PEGDA 700) using two different 2PP setups, a commercial one and a customized one. The structures' properties were tuned to study the effect of scaffold dimensions (gap size) and their mechanical properties on the adhesion and proliferation of bone marrow mesenchymal stem cells (BM-MSCs), which can serve as a model for leukemic diseases, among other hematological applications. The woodpile structures feature gap sizes of 25, 50, and 100 µm and a fixed beam diameter of 25 µm, to systematically study the optimal cell colonization that promotes healthy cell growth and potential tissue formation. The characterization of the scaffolds involved scanning electron microscopy and mechanical nanoindenting, while their suitability for supporting cell growth was evaluated with live/dead cell assays and multistaining 3D confocal imaging. In the mechanical assays of the hydrogel material, we observed two different stiffness ranges depending on the indentation depth. Larger gap woodpile structures coated with fibronectin were identified as the most promising scaffolds for 3D BM-MSC cellular models, showing higher proliferation rates. The results indicate that both the design and the employed materials are suitable for further assays, where retaining the BM-MSC stemness and original features is crucial, including studies focused on BM disorders such as leukemia and others. Moreover, the combination of 3D scaffold geometry and materials holds great potential for the investigation of cellular behaviors in a co-culture setting, for example, mesenchymal and hematopoietic stem cells, to be further applied in medical research and pharmacological studies.


Assuntos
Hidrogéis , Células-Tronco Mesenquimais , Células da Medula Óssea , Diferenciação Celular , Técnicas de Cocultura , Hidrogéis/química , Hidrogéis/farmacologia , Polímeros/química , Polímeros/farmacologia , Engenharia Tecidual/métodos , Alicerces Teciduais/química
16.
ACS Appl Polym Mater ; 4(8): 5368-5379, 2022 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-36824683

RESUMO

Poly(vinylidene fluoride) (PVDF) combined with cobalt ferrite (CFO) particles is one of the most common and effective polymeric magnetoelectric composites. Processing PVDF into its electroactive phase is a mandatory condition for featuring electroactive behavior and specific (post)processing may be needed to achieve this state, although electroactive phase crystallization is favored at processing temperatures below 60 °C. Different techniques are used to process PVDF-CFO nanocomposite structures into microspheres with high CFO dispersion, with microfluidics adding the advantages of high reproducibility, size tunability, and time and resource efficiency. In this work, magnetoelectric microspheres are produced in a one-step approach. We describe the production of high content electroactive phase PVDF and PVDF-CFO microspheres using microfluidic technology. A flow-focusing polydimethylsiloxane device is fabricated based on a 3D printed polylactic acid master, which enables the production of spherical microspheres with mean diameters ranging from 80 to 330 µm. The microspheres feature internal and external cavernous structures and good CFO distribution with an encapsulation efficacy of 80% and prove to be in the electroactive γ-phase with a mean content of 75%. The microspheres produced using this approach show suitable characteristics as active materials for tissue regeneration strategies and other piezoelectric polymer applications.

17.
Polymers (Basel) ; 13(23)2021 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-34883566

RESUMO

This work reports on the production of poly(vinylidene fluoride) (PVDF) membranes by non-solvent induced phase separation (NIPS) using N,N-dimethylformamide (DMF) as solvent and water as non-solvent. The influence of the processing conditions in the morphology, surface characteristics, structure, thermal and mechanical properties were evaluated for polymer dissolution temperatures between 25 and 150 °C and conditioning time between 0 and 10 min. Finger-like pore morphology was obtained for all membranes and increasing the polymer dissolution temperature led to an increase in the average pore size (≈0.9 and 2.1 µm), porosity (≈50 to 90%) and water contact angle (up to 80°), in turn decreasing the ß PVDF content (≈67 to 20%) with the degree of crystallinity remaining approximately constant (≈56%). The conditioning time did not significantly affect the polymer properties studied. Thus, the control of NIPS parameters proved to be suitable for tailoring PVDF membrane properties.

18.
Genet Mol Biol ; 44(4): e20210127, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34807223

RESUMO

Variations in dissolved oxygen levels are common in the Amazonian aquatic environments and the aquatic organisms that inhabit these environments developed a variety of adaptive responses to deal with such conditions. Some Amazonian fish species are tolerant to low oxygen levels and the cichlid Astronotus ocellatus is one of the most hypoxia-tolerant species. Herein, we aimed to unveil the biochemical and molecular responses that A. ocellatus presents when submitted to hypoxia. Hypoxia indicators were measured, such as plasma glucose, plasma lactate, hepatic glycogen and relative transcript levels of prolyl hydroxylase 2 (phd2) and hypoxia-inducible factor-1α (hif-1α) in juveniles of approximately 50 g exposed to 1, 3, and 5 hours of hypoxia (0.7 mg O2.L-1), followed by 3 hours of recovery in normoxia (6 mg O2.L-1). Fish exposed to hypoxia reduced liver glycogen levels within 3 hours of hypoxia, when comparing with 1 hour, and increased plasma glucose and lactate. Under the same condition, phd2 transcripts levels increased in gills, but decreased in liver. In contrast, hypoxia did not affect relative gene expression of hif-1α in both tissues. Based on the transcription pattern of phd2, these results showed that liver and gills of A. ocellatus have different molecular strategies to cope with environmental hypoxia.

19.
Sci Rep ; 11(1): 19028, 2021 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-34561469

RESUMO

The present study aimed to investigate the interaction between early diabetes and renal IR-induced AKI and to clarify the mechanisms involved. C57BL/6J mice were assigned to the following groups: (1) sham-operated; (2) renal IR; (3) streptozotocin (STZ-55 mg/kg/day) and sham operation; and (4) STZ and renal IR. On the 12th day after treatments, the animals were subjected to bilateral IR for 30 min followed by reperfusion for 48 h, at which time the animals were euthanized. Renal function was assessed by plasma creatinine and urea levels, as well urinary protein contents. Kidney morphology and gene and protein expression were also evaluated. Compared to the sham group, renal IR increased plasma creatinine, urea and albuminuria levels and decreased Nphs1 mRNA expression and nephrin and WT1 protein staining. Tubular injury was observed with increased Havcr1 and Mki67 mRNA expression accompanied by reduced megalin staining. Renal IR also resulted in increased SQSTM1 protein expression and increased proinflammatory and profibrotic factors mRNA expression. Although STZ treatment resulted in hyperglycemia, it did not induce significant changes in renal function. On the other hand, STZ treatment aggravated renal IR-induced AKI by exacerbating renal dysfunction, glomerular and tubular injury, inflammation, and profibrotic responses. Thus, early diabetes constitutes a relevant risk factor for renal IR-induced AKI.


Assuntos
Injúria Renal Aguda/etiologia , Diabetes Mellitus Tipo 1/complicações , Isquemia/complicações , Rim/irrigação sanguínea , Traumatismo por Reperfusão/complicações , Injúria Renal Aguda/diagnóstico , Injúria Renal Aguda/patologia , Albuminúria , Animais , Biomarcadores/metabolismo , Creatinina/sangue , Diabetes Mellitus Experimental/complicações , Progressão da Doença , Expressão Gênica , Túbulos Renais/patologia , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos Endogâmicos C57BL , Fatores de Risco , Proteína Sequestossoma-1/genética , Proteína Sequestossoma-1/metabolismo
20.
ACS Appl Mater Interfaces ; 13(15): 18065-18076, 2021 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-33843194

RESUMO

Portable analytical systems are increasingly required for clinical analysis or environmental monitoring, among others, being materials with tailored physicochemical properties among the main needs for successful functional implementation. This article describes the processing of fluorinated poly(vinylidene-co-trifluorethylene), P(VDF-TrFE), membranes with tailored morphological and physicochemical properties to be used as microfluidic substrates for portable analytical systems, commonly called point-of-care systems in the medical field. The morphology of the developed membranes includes spherulitic, porous, randomly oriented, and oriented fibers. Furthermore, the processed hydrophobic P(VDF-TrFE) membranes were post-treated by oxygen plasma to make them superhydrophilic. The influence of morphology and plasma treatment on the physicochemical properties and capillary flow rates was evaluated. Microfluidic systems were then designed and printed by wax printing for the colorimetric quantification of glucose. The systems comprise eight reaction chambers, each glucose concentration (25, 50, 75, and 100 mg dL-1) being measured in two reaction chambers separately and at the same time. The results demonstrate the suitability of the developed microfluidic substrates based on their tailorable morphology, improved capillary flow rate, wax print quality, homogeneous generation of colorimetric reaction, and excellent mechanical properties. Finally, the possibility of being reused, along with their electroactive properties, can lead to a new generation of microfluidic substrates based on fluorinated membranes.


Assuntos
Bioensaio/métodos , Colorimetria/métodos , Halogenação , Hidrocarbonetos Fluorados/química , Membranas Artificiais , Compostos de Vinila/química , Dispositivos Lab-On-A-Chip , Fenômenos Mecânicos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA