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1.
Vaccine ; 42(3): 556-563, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38182460

RESUMO

OBJECTIVE: In 2021, thrombosis with thrombocytopenia syndrome (TTS) was confirmed by the European Medicines Agency (EMA) as a rare side effect of the COVID-19 adenovirus vector vaccines Vaxzevria® and Jcovden®. This study aimed to describe the public's knowledge of TTS and how it affected the willingness to be vaccinated with COVID-19 vaccines and other vaccines in six European countries. METHODS: From June to October of 2022, a multi-country cross-sectional online survey was conducted in Denmark, Greece, Latvia, Netherlands, Portugal, and Slovenia. The minimum target of participants to be recruited was based on the size of the country's population. The results were analysed descriptively. RESULTS: In total, 3794 respondents were included in the analysis; across the six countries, 33.3 %-68.3 % reported being familiar with signs and symptoms of TTS, although 3.1-61.4 % of those were able to identify the symptoms correctly. The reported changes in willingness to be vaccinated against COVID-19 and with other vaccines varied per country. The largest reported change in the willingness to be vaccinated with Vaxzevria® and Jcovden® was observed in Denmark (61.2 %), while the willingness to be vaccinated with other COVID-19 vaccines changed most in Slovenia (30.4 %). The smallest decrease in willingness towards future vaccination against COVID-19 was reported in the Netherlands (20.9 %) contrasting with the largest decrease observed in Latvia (69.1 %). CONCLUSION: Knowledge about TTS seemed to have influenced the public's opinion in Europe resulting in less willingness to be vaccinated with Vaxzevria® and Jcovden®. Willingness for vaccination against COVID-19 with other vaccines and widespread use of vaccines to prevent other diseases also differed and seemed to be determined by the approaches taken by national health authorities when reacting to and communicating about COVID-19 vaccination risks. Further investigation of optimal risk communication strategies is warranted.


Assuntos
COVID-19 , Trombocitopenia , Trombose , Humanos , Vacinas contra COVID-19 , Estudos Transversais , COVID-19/prevenção & controle , ChAdOx1 nCoV-19 , Vacinação , Adenoviridae/genética
2.
Adv Healthc Mater ; : e2303861, 2023 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-38041539

RESUMO

Responsive magnetic nanomaterials offer significant advantages for innovative therapies, for instance, in cancer treatments that exploit on-demand delivery on alternating magnetic field (AMF) stimulus. In this work, biocompatible magnetic bionanocomposite films are fabricated from chitosan by film casting with incorporation of magnetite nanoparticles (MNPs) produced by facile one pot synthesis. The influence of synthesis conditions and MNP concentration on the films' heating efficiency and heat dissipation are evaluated through spatio-temporal mapping of the surface temperature changes by video-thermography. The cast films have a thickness below 100 µm, and upon exposure to AMF (663 kHz, 12.8 kA m-1 ), induce exceptionally strong heating, reaching a maximum temperature increase of 82 °C within 270 s irradiation. Further, it is demonstrated that the films can serve as substrates that supply heat for multiple hyperthermia scenarios, including: i) non-contact automated heating of cell culture medium, ii) heating of gelatine-based hydrogels of different shapes, and iii) killing of cancerous melanoma cells. The films are versatile components for non-contact stimulus with translational potential in multiple biomedical applications.

4.
Immunobiology ; 228(3): 152357, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36857907

RESUMO

Cytokines are small molecules secreted by numerous cells. Macrophage Migration Inhibitory Factor (MIF) is a cytokine initially described due to its function of inhibiting random macrophage migration. Currently, new functions have been described for MIF, such as stimulating inflammatory functions in response to infections by microorganisms including, Toxoplasma gondii. However, the primordial MIF function related to macrophages has been little addressed. The main purpose of the study was to recapitulate MIF function on macrophages in response to T. gondii infection. To achieve this goal, peritoneal macrophages were collected from C57BL/6WT and Mif1-/- mice after recruitment with thioglycolate. Macrophages were cultured, treated with 4-Iodo-6-phenylpyrimidine (4-IPP), and infected or not by T. gondii for 24 h. Following this, the culture supernatant was collected for cytokine, urea and nitrite analysis. In addition, macrophages were evaluated for phagocytic activity and T. gondii proliferation rates. Results demonstrated that T. gondii infection triggered an increase in MIF production in the WT group as well as an increase in the secretion of IL-10, TNF, IFN-γ, IL-6 and IL-17 in the WT and Mif1-/- macrophages. Regarding the comparison between groups, it was detected that Mif1-/- macrophages secreted more IL-10 compared to WT. On the other hand, the WT macrophages produced greater amounts of TNF, IFN-γ, IL-6 and IL-17. Urea production was more pronounced in Mif1-/- macrophages while nitrite production was higher in WT macrophages. T. gondii showed a greater ability to proliferate in Mif1-/- macrophages and these cells also presented enhanced phagocytic activity. In conclusion, T. gondii infection induces macrophage activation inciting cytokine production. In presence of MIF, T. gondii infected macrophages produce pro-inflammatory cytokines compatible with the M1 activation profile. MIF absence caused a dramatic reduction in pro-inflammatory cytokines that are balanced by increased levels of urea and anti-inflammatory cytokines. These macrophages presented increased phagocytic capacity and shared features activation with the M2 profile.


Assuntos
Fatores Inibidores da Migração de Macrófagos , Toxoplasma , Toxoplasmose , Animais , Camundongos , Interleucina-10 , Interleucina-17 , Interleucina-6 , Ativação de Macrófagos , Camundongos Endogâmicos C57BL , Nitritos , Toxoplasma/fisiologia
5.
J Sci Food Agric ; 103(3): 1088-1096, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35315088

RESUMO

BACKGROUND: Non-value agrifood byproducts are rich in biomolecules such as proteins and polysaccharides, and possess film-forming ability, motivating their use in the development of biodegradable plastics. This work studied the feasibility of using locust bean milling-derived dust (LBMD) as a source of biomolecules suitable for developing biodegradable plastics. RESULTS: LBMD is composed of 56% protein, 28% carbohydrate, 10% moisture, 6% lipid, and 2% ash. In addition, phenolic compounds are also present. The carbohydrates are mainly composed by (1 → 4)-mannose, (1 → 4,6)-mannose, and t-galactose glycosidic linkages. Depending on the LBMD concentration used, when employed in casting biodegradable plastics, LBMD yields transparent yellowish bioplastics with 90% elongation at break and surface water contact angles ranging from 60° to 90°. Additionally, LBMD-based bioplastics display antioxidant activity, inhibiting cationic 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radicals up to 61% in just 24 h. LBMD-based bioplastics are disintegrated when incubated on the soil surface for 34 weeks, perhaps acting as a soil nutrient. CONCLUSION: LBMD represents a potential source of biomolecules for producing transparent, flexible, water tolerant, antioxidant, and biodegradable bioplastics, opening up opportunities to implement a novel circular strategy to valorize this locust bean industry byproduct. © 2022 Society of Chemical Industry.


Assuntos
Antioxidantes , Plásticos Biodegradáveis , Plásticos Biodegradáveis/química , Manose , Biopolímeros/química , Proteínas , Água/química , Solo , Plásticos/química
6.
Int J Biol Macromol ; 229: 224-235, 2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36586651

RESUMO

Asymmetric wound dressings have captured researchers' attention due to their ability to reproduce the structural and functional properties of the skin layers. Furthermore, recent studies also report the benefits of using near-infrared (NIR) radiation-activated photothermal therapies in treating infections and chronic wounds. Herein, a chitosan (CS) and reduced graphene oxide (rGO) hydrogel (CS_rGO) was combined with a polycaprolactone (PCL) and cellulose acetate (CA) electrospun membrane (PCL_CA) to create a new NIR-responsive asymmetric wound dressing. The rGO incorporation in the hydrogel increased the NIR absorption capacity and allowed a mild hyperthermy effect, a temperature increase of 12.4 °C when irradiated with a NIR laser. Moreover, the PCL_CA membrane presented a low porosity and hydrophobic nature, whereas the CS_rGO hydrogel showed the ability to provide a moist environment, prevent exudate accumulation and allow gaseous exchanges. Furthermore, the in vitro data demonstrate the capacity of the asymmetric structure to act as a barrier against bacteria penetration as well as mediating a NIR-triggered antibacterial effect. Additionally, human fibroblasts were able to adhere and proliferate in the CS_rGO hydrogel, even under NIR laser irradiation, presenting cellular viabilities superior to 90 %. Altogether, our data support the application of the NIR-responsive asymmetric wound dressings for skin regeneration.


Assuntos
Quitosana , Hipertermia Induzida , Nanofibras , Humanos , Quitosana/química , Hidrogéis/farmacologia , Hidrogéis/química , Nanofibras/química , Antibacterianos/farmacologia
7.
Eur J Dermatol ; 33(6): 674-679, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38465549

RESUMO

Actinic keratosis (AK) is the most common pre-malignant cutaneous lesion of the skin, often associated with field cancerization. Daylight photodynamic therapy (DL-PDT) is used as treatment, showing good histological results. Reflectance confocal microscopy (RCM) may be useful as a non-invasive, real-time approach to monitor treatment, however, there is a lack of data on the correlation between RCM and histopathological findings in AK patients treated with DL-PDT. To correlate histological and RCM findings and evaluate the efficacy of DL-PDT in patients with AK and field cancerization treated with DL-PDT. Patients with field cancerization and a minimum of six AK lesions on the face were included in the study. A single session combining methyl aminolevulinate followed by two-hour daylight exposure of the face was performed. RCM and biopsy were performed before and after three months of the intervention to compare efficacy between patients using the Wilcoxon test, and concordance of the findings based on the different methods was analysed using the Kappa test. Twenty-four patients completed the study. An improvement in photodamage and a decrease in the number of AK lesions (45.3% reduction) was observed. Regression in atypia and dysplasia was observed via histopathology and RCM, however, there was poor agreement between the methods. No changes were observed after treatment for inflammation, fibroplasia and acantholysis. Concordance between histological and RCM findings was poor, suggesting that RCM cannot replace the histopathological examination, however, it may be used as an adjuvant test for follow-up of patients. Despite this, DL-PDT proved to be an effective method for treating AK.


Assuntos
Ceratose Actínica , Fotoquimioterapia , Humanos , Ceratose Actínica/diagnóstico por imagem , Ceratose Actínica/tratamento farmacológico , Ceratose Actínica/etiologia , Fotoquimioterapia/métodos , Ácido Aminolevulínico/uso terapêutico , Inflamação , Protetores Solares/uso terapêutico , Microscopia Confocal/métodos , Fármacos Fotossensibilizantes/uso terapêutico , Resultado do Tratamento
8.
Rev. saúde pública (Online) ; 57(supl.1): 6s, 2023. tab, graf
Artigo em Inglês, Português | LILACS | ID: biblio-1442136

RESUMO

ABSTRACT OBJECTIVE To estimate seroprevalence of SARS-CoV-2 antibodies in schoolchildren aged 4 to 14 years living in the city of São Paulo, according to clinical, demographic, epidemiological, and social variables, during the school closure period as a measure against covid-19 spread. METHODS A serological survey was made in September 2020 with a random sample stratified by school system (municipal public, state public and private) type. A venous blood sample was collected using the Wondfo SARS-CoV-2 Antibody Test (lateral flow method) for detection of total SARS-CoV-2 virus antibodies. Semi-structured questionnaires were applied to collect clinical, demographic, social, and epidemiological data. RESULTS Seroprevalence of SARS-CoV-2 antibodies in schoolchildren was of 16.6% (95%CI 15.4-17.8). The study found higher seroprevalence in the municipal (18.5%; 95%CI 16.6-20.6) and state (16.2%; 95%CI 14.4-18.2) public school systems compared to the private school system (11.7; 95%CI 10.0-13.7), among black and brown students (18.4%; 95%CI 16.8-20.2) and in the most vulnerable social stratum (18.5 %;95%CI 16.9-20.2). Lower seroprevalence was identified in schoolchildren who reported following the recommended protective measures against covid-19. CONCLUSION Seroprevalence of SARS-CoV-2 antibodies is found mainly in the most socially vulnerable schoolchildren. This study can contribute to support public policies that reinforce the importance of suspending face-to-face classes and developing strategies aimed at protective measures and monitoring of the serological status of those who have not yet been included in the vaccination schedule.


RESUMO OBJETIVO Estimar a soroprevalência de anticorpos do vírus SARS-CoV-2 em escolares de quatro a 14 anos de idade residentes no município de São Paulo, segundo variáveis clínicas, demográficas, epidemiológicas e sociais, durante o período de fechamento das escolas como medida de controle da covid-19. MÉTODOS Realizou-se um inquérito sorológico em setembro de 2020 com amostra aleatória estratificada por tipo de rede de ensino (pública municipal, pública estadual e privada). Foi coletada amostra de sangue venoso utilizando-se o teste de imunoensaio de fluxo lateral da fabricante Wondfo para detecção de anticorpos totais contra o vírus SARS-CoV-2. Aplicaram-se questionários semiestruturados para o levantamento de dados clínicos, demográficos, sociais e epidemiológicos. RESULTADOS A soroprevalência de anticorpos do vírus SARS-CoV-2 em escolares foi de 16,6% (IC95% 15,4-17,8). O estudo encontrou soroprevalências mais elevadas na rede pública municipal (18,5%; IC95% 16,6-20,6) e estadual (16,2%; IC95% 14,4-18,2) em relação à rede privada (11,7; IC95% 10,0-13,7) e entre escolares da raça/cor preta e parda (18,4%; IC95% 16,8-20,2) e no estrato social mais vulnerável (18,5%; IC95% 16,9-20,2). A pesquisa identificou menores soroprevalências nos escolares que relataram seguir as medidas recomendadas de proteção contra a covid-19. CONCLUSÃO A soroprevalência de anticorpos contra o vírus SARS-CoV-2 atinge principalmente os escolares socialmente mais vulneráveis. Este estudo pode contribuir para embasar políticas públicas que reforcem a importância da suspensão das aulas presenciais e da necessidade de estratégias de medidas de proteção e acompanhamento do status sorológico daqueles que ainda não foram contemplados no calendário vacinal.


Assuntos
Humanos , Masculino , Feminino , Criança , Estudos Soroepidemiológicos , Criança , Adolescente , SARS-CoV-2 , COVID-19/epidemiologia
9.
Gels ; 8(11)2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36354614

RESUMO

Supramolecular peptide hydrogels have many important applications in biomedicine, including drug delivery applications for the sustained release of therapeutic molecules. Targeted and selective drug administration is often preferential to systemic drug delivery, as it can allow reduced doses and can avoid the toxicity and side-effects caused by off-target binding. New discoveries are continually being reported in this rapidly developing field. In this review, we report the latest developments in supramolecular peptide-based hydrogels for drug delivery, focusing primarily on discoveries that have been reported in the last four years (2018-present). We address clinical points, such as peptide self-assembly and drug release, mechanical properties in drug delivery, peptide functionalization, bioadhesive properties and drug delivery enhancement strategies, drug release profiles, and different hydrogel matrices for anticancer drug loading and release.

10.
Int J Mol Sci ; 23(22)2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36430620

RESUMO

Superparamagnetic nanoparticles are of high interest for therapeutic applications. In this work, nanoparticles of calcium-doped manganese ferrites (CaxMn1-xFe2O4) functionalized with citrate were synthesized through thermally assisted oxidative precipitation in aqueous media. The method provided well dispersed aqueous suspensions of nanoparticles through a one-pot synthesis, in which the temperature and Ca/Mn ratio were found to influence the particles microstructure and morphology. Consequently, changes were obtained in the optical and magnetic properties that were studied through UV-Vis absorption and SQUID, respectively. XRD and Raman spectroscopy studies were carried out to assess the microstructural changes associated with stoichiometry of the particles, and the stability in physiological pH was studied through DLS. The nanoparticles displayed high values of magnetization and heating efficiency for several alternating magnetic field conditions, compatible with biological applications. Hereby, the employed method provides a promising strategy for the development of particles with adequate properties for magnetic hyperthermia applications, such as drug delivery and cancer therapy.


Assuntos
Hipertermia Induzida , Nanopartículas , Manganês , Cálcio , Hipertermia Induzida/métodos , Nanopartículas/química , Cálcio da Dieta , Campos Magnéticos , Estresse Oxidativo
11.
Int J Mol Sci ; 23(19)2022 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-36233112

RESUMO

Employing amino acids and peptides as molecular building blocks provides unique opportunities for generating supramolecular hydrogels, owing to their inherent biological origin, bioactivity, biocompatibility, and biodegradability. However, they can suffer from proteolytic degradation. Short peptides (<8 amino acids) attached to an aromatic capping group are particularly attractive alternatives for minimalistic low molecular weight hydrogelators. Peptides with low critical gelation concentrations (CGCs) are especially desirable, as the low weight percentage required for gelation makes them more cost-effective and reduces toxicity. In this work, three dehydrodipeptides were studied for their self-assembly properties. The results showed that all three dehydrodipeptides can form self-standing hydrogels with very low critical gelation concentrations (0.05−0.20 wt%) using a pH trigger. Hydrogels of all three dehydrodipeptides were characterised by scanning tunnelling emission microscopy (STEM), rheology, fluorescence spectroscopy, and circular dichroism (CD) spectroscopy. Molecular modelling was performed to probe the structural patterns and interactions. The cytotoxicity of the new compounds was tested using human keratinocytes (HaCaT cell line). In general, the results suggest that all three compounds are non-cytotoxic, although one of the peptides shows a small impact on cell viability. In sustained release assays, the effect of the charge of the model drug compounds on the rate of cargo release from the hydrogel network was evaluated. The hydrogels provide a sustained release of methyl orange (anionic) and ciprofloxacin (neutral), while methylene blue (cationic) was retained by the network.


Assuntos
Dipeptídeos , Lisina , Aminoácidos/química , Ciprofloxacina , Preparações de Ação Retardada , Liberação Controlada de Fármacos , Humanos , Hidrogéis/química , Azul de Metileno , Peptídeos/química
12.
Soft Matter ; 18(44): 8384-8397, 2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36193825

RESUMO

Supramolecular short peptide-based gels are promising materials for the controlled release of drugs (e.g. chemotherapeutic drugs) owing to the biocompatibility and similarity to cell matrix. However, the drug encapsulation and control over its release, mainly the hydrophilic drugs, can be a cumbersome task. This can be overcome through encapsulation/compartmentalization of drugs in liposomes, which can also enable spatiotemporal control and enhanced drug release through a trigger, such as photothermia. Having this in mind, we explored the assembly of silica-coated gold nanoparticles and liposomes (storage units) with dehydropeptide-based hydrogels as a proof-of-concept to afford peptide-based NIR light-responsive lipogels. Several liposomes compositions were assessed that displayed influence on the final assembly properties by combining with silica-coated gold nanorods (∼106 nm). Gold nanospheres (∼11 nm) were used to study the preparation method, which revealed the importance of initially combine liposomes with nanoparticles and then the gelator solution to achieve a closer proximity of the nanoparticles to the liposomes. The control over a hydrophilic model drug, 5(6)-carboxyfluorescein, was only achieved by its encapsulation in liposomes, in which the presence of silica-coated nanorods further enabled the use of photothermia to induce the liposomes phase transition and stimulate the drug release. Further, both composites, the liposomes and silica-coated gold nanorods, induced a lower elastic modulus, but also provided an enhanced gelation kinetics. Hereby, this work advances fabrication strategies for the development of short peptide-based hydrogels towards on-demand, sustained and controlled release of hydrophilic drugs through photothermia under NIR light irradiation.


Assuntos
Lipossomos , Nanopartículas Metálicas , Liberação Controlada de Fármacos , Ouro , Sistemas de Liberação de Medicamentos/métodos , Preparações de Ação Retardada , Hidrogéis , Dióxido de Silício , Peptídeos
14.
Diagn. tratamento ; 27(3): 80-4, jul-set. 2022. ilus, ilus
Artigo em Português | LILACS | ID: biblio-1380674

RESUMO

Contexto: A pandemia da doença do coronavírus (COVID-19) revelou uma miríade de manifestações sistêmicas e cutâneas possivelmente relacionadas à infecção por síndrome respiratória aguda grave ocasionada pelo coronavírus (SARS-CoV-2). O comprometimento pulmonar é a causa mais frequente de hospitalização e a progressão para síndrome respiratória aguda grave geralmente requer tratamento com ventilação mecânica na posição pronada. Períodos prolongados e repetidos de pronação aumentam o risco de complicações, incluindo úlcera de pressão, cegueira e neuropatia periférica. Descrição do caso: Relatamos três casos de complicações cutâneas relacionadas à ventilação em pronação avaliadas durante interconsultas no maior hospital terciário universitário da América Latina, e salientamos potenciais causas e medidas de prevenção. Discussão: Complicações da ventilação em pronação para tratamento da COVID-19 são provavelmente resultantes da interação entre múltiplos fatores, dentre os quais as condições clínicas do paciente, períodos prolongados na posição pronada e limitações para mudanças de decúbito. Conclusões: Medidas de prevenção para complicações da pronação e diagnóstico precoce são fundamentais para evitar aumento da morbidade e sequelas graves e irreversíveis associadas à COVID-19.


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Dermatopatias , Pronação , Ventilação Pulmonar , SARS-CoV-2 , COVID-19
15.
Front Med (Lausanne) ; 9: 968272, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36035431

RESUMO

Introduction: Cancer and corresponding available treatments are associated with substantial symptoms and functional limitations. In this context, collection of patient-reported outcomes (PRO) in clinical trials gained special interest and is recommended by regulatory authorities. Within clinical trials framework, PRO may provide evidence to support medicines approval, labeling and marketing claims. This study aims to analyze the existing evidence based on PRO as part of new oncology indications receiving positive opinions issued by the European Medicines Agency (EMA) between 2017 and 2020 and to identify PRO related label claims granted. Methodology: Oncology medicinal products and indications approved by the European Commission following a positive opinion from the EMA between 2017 and 2020 were identified. European Public Assessment Report (EPAR) and Summary of Product Characteristics (SmPC) were reviewed for each medicinal product to identify use of PRO and PRO label claims. Results: A total of 128 oncology indications, corresponding to 76 medicines, were approved; of those, 100 (78.1%) included PRO in the confirmatory clinical trials. Thirty-seven indications were supported by double-blind randomized trials and the remainder 63 by open-label trials. Out of the 104 confirmatory trials analyzed, PRO were defined as a secondary endpoint in 60 studies (57.7%), exploratory in 31 (29.8%) and as both in 13 (12.5%). In total, 54 different PRO measures (PROM) were used, of those 41 (75.9%) were disease-specific measures. Nevertheless, PROM selected relied on the EORTC (41.3%), FACIT (17.1%) and EQ-5D (29.2%) measures. A total of 76 indications (59.4%) had PRO reviewers comments included in the EPAR, however only 22 indications (17.8%) included label claims in the SmPC. The reasons identified in the EMA assessment supporting the exclusion of PRO claims were described for 34 indications (44.7%). Conclusions: Despite growing recognition of the value of PRO data for the development of improved cancer therapies, PRO implementation remains challenging. The main reasons identified in our study are related with study design, missing data, study conduct and PROM selection.

16.
Nanomaterials (Basel) ; 12(11)2022 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-35683726

RESUMO

Magnetite nanoparticles were synthesized by the co-precipitation method with and without the assistance of an additive, namely, gelatin, agar-agar or pectin, using eco-friendly conditions and materials embodying a green synthesis process. X-ray diffraction and transmission electron microscopy were used to analyze the structure and morphology of the nanoparticles. Magnetic properties were investigated by SQUID magnetometry and 57Fe Mössbauer spectroscopy. The results show that the presence of the additives implies a higher reproducibility of the morphological magnetic nanoparticle characteristics compared with synthesis without any additive, with small differences associated with different additives. To assess their potential for magnetic hyperthermia, water-based suspensions of these nanoparticles were prepared with and without citric acid. The stable solutions obtained were studied for their structural, magnetic and heating efficiency properties. The results indicate that the best additive for the stabilization of a water-based emulsion and better heating efficiency is pectin or a combination of pectin and agar-agar, attaining an intrinsic loss power of 3.6 nWg-1.

17.
Distúrb. comun ; 34(2): e55596, jun. 2022. ilus, tab
Artigo em Português | LILACS | ID: biblio-1396643

RESUMO

Introdução: Discussões sobre a produção da ciência, em especial sobre a produtividade científica, contribuem para o planejamento e aperfeiçoamento da pesquisa e formação. Objetivo: Analisar a publicação de artigos originais da Revista Distúrbios da Comunicação no período de 2016-2020, comparando com resultados de pesquisa anterior. Método: Pesquisa documental, realizada por meio de estudo bibliométrico de artigos a partir da coleta dos seguintes dados: volume e número da revista, título, resumo, instituição de origem dos autores, com respectivo registro da região geográfica do primeiro autor, descritores, áreas temáticas, tipo de estudo, número de centros de pesquisa, e tamanho e faixa etária da amostra. A análise dos dados foi descritiva, numérica e percentual. Resultados: Foram analisados 258 artigos originais e os assuntos mais frequentes envolviam a temática de Audição e equilíbrio (80;31,1%), seguida de Linguagem (73;28,3%); tipo de estudo observacional (199;77,1%), realizados em um único centro (254; 98,4%), com tamanho médio de amostra de 74,3 sujeitos, na faixa etária prevalente de 19 a 59 anos (119;46,1%). Conclusão: Como áreas basilares da Fonoaudiologia, Audição e Equilíbrio e Linguagem são as áreas com mais pesquisas. O aumento de pesquisas, nas áreas de Disfagia e Saúde Coletiva aponta para o importante movimento de consolidação de campos mais recentemente constituídos. Constata-se a necessidade de Programas de Pós-Graduação e centros de pesquisa promoverem ações estratégicas que potencializem pesquisas multicêntricas e ampliem o desenvolvimento de estudos de intervenção. Recomenda-se atenção especial para a escolha de descritores para facilitar o acesso e produzir consequentemente maior impacto para a pesquisa e para a área.


Introduction: Discussions on the production of science, especially on scientific productivity, contribute to the planning and improvement of research and professional qualification. Objective: To evaluate the publication of original articles of the Revista Distúrbios da Comunicação from 2016 to 2020, comparing with previous research results. Method: Documentary research, carried out through a bibliometric study of articles from the collection of the following data: volume and number of the journal, title, abstract, institution of the authors, with respective record of the geographic region of the first author, descriptors, topics, study design, number of research centers, and size and age of the sample. There was a descriptive, numerical and percentage analysis of the data. Results: 258 original articles were analyzed and the most frequent subjects were related to Hearing and Balance (80;31.1%), followed by Language (73;28.3%); type of observational study (199;77.1%), conducted in a single center (254; 98.4%), with an average sample size of 74.3 subjects, in the prevalent age group from 19 to 59 years (119;46.1%). Conclusion: As basic areas of Speech-Language Pathology, Hearing and Balance and Language are the areas with the highest number of studies. The increase in the number of studies in the areas of Dysphagia and Collective Health suggests an important movement of consolidation of more recently constituted fields. There is a need for Graduate Programs and research centers to promote strategic actions that enhance multicentric research and expand the development of intervention studies. Special attention should be given to the selection of descriptors by the authors, in order to facilitate access and, consequently, produce greater impact for the research and for the area.


Introducción: Los debates sobre la producción de ciencia, especialmente sobre la productividad científica, contribuyen a la planificación y mejora de la investigación y la formación. Objetivo: analizar la publicación de artículos originales de la Revista Distúrbios da Comunicação en el período 2016-2020, comparando con resultados de investigaciones anteriores. Método: Investigación documental, realizada a través de un estudio bibliométrico de artículos de la recopilación de los siguientes datos: volumen y número de la revista, título, resumen, institución de origen de los autores, con registro respectivo de la región geográfica del primer autor, descriptores, áreas temáticas, tipo de estudio, número de centros de investigación, y tamaño y edad de la muestra. El análisis de los datos fue descriptivo, numérico y porcentual. Resultados: Se analizaron 258 artículos originales y los sujetos más frecuentes fueron el tema Audición y equilibrio (80;31,1%), seguido de Lenguaje (73;28,3%); tipo de estudio observacional (199;77,1%), realizado en un solo centro (254; 98,4%), con un tamaño muestraal promedio de 74,3 sujetos, en el grupo de edad prevalente de 19 a 59 años (119;46,1%). Conclusión: Como áreas básicas de logopedia, Audición y Equilibrio y Lenguaje son las áreas con más investigación. El aumento de la investigación en las áreas de Disfagia y Salud Colectiva apunta al importante movimiento de consolidación de campos más recientemente constituidos. Se observa la necesidad de programas de posgrado y centros de investigación para promover acciones estratégicas que potencien la investigación multicéntrica y amplíen el desarrollo de los estudios de intervención. Se recomienda prestar especial atención a la elección de descriptores para facilitar el acceso y, en consecuencia, producir un mayor impacto para la investigación y, en consecuencia, para el área.


Assuntos
Publicações Periódicas como Assunto/estatística & dados numéricos , Comunicação e Divulgação Científica , Fonoaudiologia/tendências , Pesquisa , Bibliometria , Bibliometria , Indicadores de Produção Científica
18.
Soft Matter ; 18(20): 3955-3966, 2022 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-35551321

RESUMO

Short peptides capped on the N-terminus with aromatic groups are often able to form supramolecular hydrogels-self-assembled networks of fibrils able to trap water molecules. Typically, these hydrogelators can form stiff gels at concentrations of 0.1 to 1.0 wt%-i.e. they consist of mainly water. The properties of these soft materials mimic those of the extracellular matrix (ECM) of biological tissue and therefore they have found many biomedical uses in tissue engineering, wound healing, drug delivery, biosensing and bioprinting applications. In drug delivery strategies related to cancer therapy, injectable hydrogels can serve as a depot formulation, where a sustained release of the chemotherapeutic from near the tumour site allows reduced doses and, therefore, decreased side effects. To further target cancer cells, folic acid-conjugated hydrogels and nanostructures are often sought, to exploit the overexpression of folate receptors on cancer cells-an approach which can allow the selective cellular uptake of an encapsulated drug. In this present study, two known dipeptide folate receptor ligands (1 and 2) recently identified from a screen of a DNA-encoded compound library, were synthesised and investigated for their hydrogelation ability and cytotoxicity. Compound 1, containing a naproxen capping group, rapidly forms hydrogels at concentrations as low as 0.03 wt%-one of the lowest critical gelation concentrations (CGCs) known for a supramolecular hydrogelator. In contrast, compound 2, which contains a 3-indolepropionic acid capping group, was unable to form hydrogels under a range of conditions and concentrations, instead forming nanospheres with diameters of 0.5 µm. Hydrogels of 1 were characterised by STEM microscopy, rheology, fluorescence spectroscopy and circular dichroism. Both compounds 1 and 2 had no impact on the proliferation of kerotinocytes (HaCaT cells) at concentrations up to 100 µM. Compound 1, containing the NSAID, was tested for anti-inflammatory activity in a human cyclooxygenase-1/2 model. The rate of the release of model drug compounds from within hydrogels of 1 was also investigated.


Assuntos
Hidrogéis , Naproxeno , Ácido Fólico , Humanos , Hidrogéis/química , Ligantes , Naproxeno/química , Naproxeno/farmacologia , Água
19.
Nanoscale ; 14(14): 5488-5500, 2022 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-35332904

RESUMO

Self-assembled short peptide-based gels are highly promising drug delivery systems. However, implementing a stimulus often requires screening different structures to obtain gels with suitable properties, and drugs might not be well encapsulated and/or cause undesirable effects on the gel's properties. To overcome this challenge, a new design approach is presented to modulate the release of doxorubicin as a model chemotherapeutic drug through the interplay of (di)phenylalanine-coated magnetic nanoparticles, PEGylated liposomes and doxorubicin co-assembly in dehydropeptide-based gels. The composites enable an enhancement of the gelation kinetics in a concentration-dependent manner, mainly through the use of PEGylated liposomes. The effect of the co-assembly of phenylalanine-coated nanoparticles with the hydrogel displays a concentration and size dependence. Finally, the integration of liposomes as doxorubicin storage units and of nanoparticles as composites that co-assemble with the gel matrix enables the tuneability of both passive and active doxorubicin release through a thermal, and a low-frequency alternating magnetic field-based trigger. In addition to the modulation of the gel properties, the functionalization with (di)phenylalanine improves the cytocompatibility of the nanoparticles. Hereby, this work paves a way for the development of peptide-based supramolecular systems for on-demand and controlled release of drugs.


Assuntos
Hidrogéis , Lipossomos , Doxorrubicina/farmacologia , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Géis/química , Hidrogéis/química , Campos Magnéticos , Peptídeos/química , Fenilalanina , Polietilenoglicóis
20.
Am J Dermatopathol ; 44(3): 190-195, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34966051

RESUMO

ABSTRACT: Cutaneous adnexal tumors are benign and malignant neoplasms that undergo morphological differentiation into cutaneous adnexa, comprising pilosebaceous, eccrine, or apocrine units. Reflectance confocal microscopy is a noninvasive diagnostic method that enables in vivo visualization of tissues at a similar resolution as conventional histopathology. The use of this method in skin imaging over the past several years has improved dermatological diagnoses, potentiating its wide application, especially for benign and malignant skin tumors. We describe the use of reflectance confocal microscopy in cases of trichoepithelioma, sebaceoma, and fibrofolliculoma and correlate the resulting clinical, histopathological, and confocal microscopy images.


Assuntos
Síndrome de Muir-Torre/patologia , Neoplasias de Anexos e de Apêndices Cutâneos/patologia , Síndromes Neoplásicas Hereditárias/patologia , Neoplasias Cutâneas/patologia , Adulto , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Síndrome de Muir-Torre/diagnóstico , Neoplasias de Anexos e de Apêndices Cutâneos/diagnóstico , Síndromes Neoplásicas Hereditárias/diagnóstico , Neoplasias Cutâneas/diagnóstico
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