MgO nanoparticles obtained by Pulsed Laser Ablation in Liquid: a study on fabrication versatility aiming different applications

Apresentação efetuada em "Junior Euromat 2022", em Coimbra, 2022Nano and micro-sized metal particles are used in diverse fields, from electronics to biomedical. Among them, Magnesia, also known as magnesium oxide (MgO), is one of the most interesting metal oxides due to its unique properties, such as a large electrochemically active surface area and chemical stability. Although chemical routes such as chemical reactions, thermal evaporation,sol-gel, chemical vapor deposition and hydrothermal treatments are mainly used to fabricate metal oxide nanoparticles, they require the use of toxic reagents and long processing times. Thus, developing a simple green synthetic process for preparing MgO nanoparticles remains a challenging topic of investigation. Pulsed laser ablation in liquid (PLAL) has emerged as a potential alternative to chemical methods because it does not require chemicals, generates no waste, and produces high-purity particles. By changing some parameters such as the laser wavelength, laser fluence, and liquid media the size and shape of the particles produced can be tailored. The obtained particles can be added to act as anti-biofilm agents on coatings. Both influence of the liquid medium and the laser energy on nanoparticle composition and morphology are investigated in this work, as well as the effects of laser energy and different liquid media on the properties and characteristics of these nanoparticles.Acknowledgements: This work was supported by Fundação para a Ciência e Tecnologia through the grant 2020.07257.BD, the projects UIDB/04436/2020 and UIDP/04436/2020. PTDC/EME-EME/1442/2020(Add2MechBio). Additionally, this work was developed within the project CICECO-Aveiro Institute of Materials, UIDB/50011/2020, UIDP/50011/2020 & LA/P/0006/2020, financed by national funds through the FCT/MEC (PIDDAC)

Antimicrobial evaluation of gelatin–based films incorporated with chitosan in the conservation of fish fillets / Avaliação antimicrobiana de filmes à base de gelatina incorporados com quitosano na conservação de filtes de peixe

Materials obtained from biodegradable polymers can be an alternative to reduce the environmental impact caused by petroleum–derived polymers. Materials of different origins have been considered as a raw material with technical and economic feasibility for the development of packaging films. However, it is required that these alternative materials, in addition to being biodegradable, have beneficial properties in food preservation. In this context, biodegradable films based on fish gelatin, and fish gelatin with chitosan incorporation, were prepared and characterized in terms of their mechanical properties (tensile strength (TS) and elongation (E)), permeation (WVP), and antimicrobial activity in the conservation of tilapia fillets (Tilapia rendalli). Regarding the mechanical and permeation properties, the results showed that the incorporation of chitosan to the gelatin films promotes an increase in TS and E, and a reduction in WVP. As for the antimicrobial property in the conservation of tilapia fillets, both films showed satisfactory activity against the pathogenic microorganism Staphylococcus aureus. These results indicate that fish gelatin–based films with chitosan incorporation are promising as active packaging in the conservation of fish fillets

Familial history and prevalence of BRCA1, BRCA2 and TP53 pathogenic variants in HBOC Brazilian patients from a public healthcare service

Cancer; Genetics; Risk factorsCáncer; Genética; Factores de riesgoCàncer; Genètica; Factors de riscSeveral studies have demonstrated the cost-effectiveness of genetic testing for surveillance and treatment of carriers of germline pathogenic variants associated with hereditary breast/ovarian cancer syndrome (HBOC). In Brazil, seventy percent of the population is assisted by the public Unified Health System (SUS), where genetic testing is still unavailable. And few studies were performed regarding the prevalence of HBOC pathogenic variants in this context. Here, we estimated the prevalence of germline pathogenic variants in BRCA1, BRCA2 and TP53 genes in Brazilian patients suspected of HBOC and referred to public healthcare service. Predictive power of risk prediction models for detecting mutation carriers was also evaluated. We found that 41 out of 257 tested patients (15.9%) were carriers of pathogenic variants in the analyzed genes. Most frequent pathogenic variant was the founder Brazilian mutation TP53 c.1010G > A (p.Arg337His), adding to the accumulated evidence that supports inclusion of TP53 in routine testing of Brazilian HBOC patients. Surprisingly, BRCA1 c.5266dupC (p.Gln1756fs), a frequently reported pathogenic variant in Brazilian HBOC patients, was not observed. Regarding the use of predictive models, we found that familial history of cancer might be used to improve selection or prioritization of patients for genetic testing, especially in a context of limited resources.We are very thankful to all patients and their families who participated in this study. We thank Eliana Abdelhay for providing the Ion AmpliSeq customized panel and funding the sequencing costs for this panel. And we also thank the Bioinformatics Core Facility (INCA-RJ), in special Dr. Nicole Scherer, for their support in this study. This work was supported by Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq, Brazil: project 304339/2018-0), Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ, Brazil: projects 200.928/2021 and 211.309/2021), Fundação Ary Frauzino para Pesquisa e Controle do Câncer (Brazil), SWISS-BRIDGE Foundation, and Ministry of Health (Brazil)

A novel approach for micro-antenna fabrication on ZrO2 substrate assisted by laser printing for smart implants

The use of Yttria-stabilized tetragonal zirconia polycrystals (Y-TZP) in medicine has rapidly expanded over the past decade, driven by its advantageous properties, showing potential to overcome titanium alloy in implant fabrication. The release of metal ions and the aesthetic problems of titanium alloy implants are the main reasons for this trend. In addition to meeting expectations regarding its properties, an implant must possess intrinsic capacities such as auto-diagnostic and auto-treatment. Thus, based on the concept of smart implants, this work proposes a hybrid approach for printing a part of the communication system of a zirconia implant by resorting to laser technology, aiming to endow the implant with intrinsic capacities. Therefore, the antenna was designed and then printed on the zirconia surface. The laser was applied as a versatile tool, whether for preparing the surface of the material in a subtractive way, by creating the micro-cavity, or for printing the silver-based antenna in an additive way through laser technology. The silver powder was used as the conductor material of the antenna. The results revealed that the antenna is capable of communicating from inside the body with the outside world without needing to have an exterior antenna attached to the skin.This work has been supported by the FCT (Fundação para a Ciência e Tecnologia -Portugal) in the scope of the projects UID/EEA/04436/2019; Magsense_POCI-01-0247-FEDER-033783, Add.Additive_Manufacturing to Portuguese Industry_POCI-01-0247-FEDER-024533, grant SFRH/BD/ 116554/2016 and the CNPq (Conselho Nacional de Desenvolvimento Científico e Tecnológico) for the grant 205791/2014-

CORPO E ORIGAMI: UM ESTUDO SOBRE DOBRAS E SUA INOVAÇÃO DENTRO DA ARTE CONTEMPORÂNEA

Esse artigo analisa a arte contemporânea em comunhão com as técnicas criativas do corpo e do origami, gerando o entrelaçamento entre as artes manuais e corporais e a tecnologia a elas aplicada. Em um primeiro momento, é analisado o cenário contemporâneo, as novas tecnologias e os caminhos da sociedade atual. Em um segundo momento, considera-se o comportamento do corpo e do origami inseridos dentro desse novo contexto. Por fim, são analisados alguns projetos que utilizam como principal alicerce a performance corporal e as dobraduras japonesas

Laser printing of micro-electronic communication systems for smart implants applications

Endow the implant with intrinsic communication system between sensors and actuators or between implant and patient is a key factor for its long-term success. The capacity of early diagnosis of failures and the ability to remedy them are necessary to minimize expensive complications and reducing revision procedures. Ti6Al4V is the most used titanium alloy for implant’s fabrication. In this sense, this work presents a promising approach to print communication systems by using laser technology, aiming integrate the smart components on titanium implants. Laser has been employed as a versatile tool to modify the surface in different ways, such as texturing, oxidizing and sintering. Silver wires have been printed on Ti6Al4V surface in order to conduct electrical current. To minimize current loss for the substrate, titanium oxide layer has been produced by different methods (laser and anodization). Laser sintering (LS) has been also compared to a conventional method (Hot-pressing- HP) to consolidate the silver powder into the cavities. In comparison to the conventional techniques, laser demonstrated to be a competitive approach to oxidizing the surface and also for consolidating the micro-wires on Ti6Al4V surface. Consequently, the micro-wires printed by laser approach presented satisfactory results in terms of electrical resistance, actuating as the conductor path for electrical current, with values of 0.0131 Ω, which is similar to the resistance of the wire printed in an insulator substrate.This work has been supported by FCT (Fundação para a Ciência e Tecnologia -Portugal) in the scope of the projects UID/EEA/04436/ 2019 and NORTE-01-0145-FEDER-000018-HAMaBICo and Add.Additive_Manufacturing to Portuguese Industry_POCI-01-0247- FEDER-024533. I wish to thank the CNPq (205791/2014-0)

A falha na prevenção, subnotificação e conhecimento da sífilis congênita

A sífilis congênita corresponde à infecção do feto pelo Treponema pallidum, sendo transmitida via placentária durante o parto ou em qualquer momento da gestação. É uma doença de notificação compulsória, que apresenta até 40% de taxa de mortalidade. Estudos da Organização Mundial de Saúde evidenciam altos índices de SC na população mundial, em que na incidência de 12 milhões de casos de sífilis anualmente no mundo, 1 milhão ocorre em gestantes. O objetivo desta revisão é compreender os motivos do crescimento da taxa de transmissão vertical da sífilis, relacionando os pontos vulneráveis das instituições de saúde que englobam subnotificação, falha nas estratégias de prevenção e falta de conhecimento dos profissionais dos diversos níveis de atenção. Trata-se de um resumo expandido a partir de 5 artigos mais recentes (2016 a 2018) selecionados na base de dados Scielo e Medline, com uso dos descritores em ciências da saúde (DeCS): “Syphillis”, “Congenital”, “Primary Prevention”. Conclui-se com essa revisão que o controle da sífilis peca nos três pilares básicos: prevenção, notificação e conhecimento. É inegável que esses fatores estão interligados e a falha de um deles leva a ineficácia de todos

Rhizobacteria potential in the control of Meloidogyne incognita in fig

A figueira é economicamente importante pelo papel social que representa no contexto da agricultura familiar. No entanto, sua viabilidade econômica pode ser comprometida em áreas infestadas pelo nematoide das galhas (Meloidogyne incognita) devido à carência de medidas de controle efetivas e disponíveis. Assim, a inserção do controle biológico no manejo integrado dessa praga constitui-se como uma estratégia importante. As rizobactérias são consideradas biocontroladoras promissoras por promover o crescimento vegetal e/ou inibir a ação parasítica dos fitonematoides sobre as plantas hospedeiras. Dessa forma, objetivou-se com esse trabalho, avaliar o desempenho de 14 isolados bacterianos provenientes da rizosfera de figueira e de rochas de folhelhos betuminosos, no biocontrole de M. incognita em figueira. Mudas de figueira cv. ‘Roxo de Valinhos' microbiolizadas com os isolados bacterianos foram transplantadas em solo naturalmente infestado com M. incognita. Sete isolados (F08, F25, F71, F76, F78, FB34 e FB59), reduziram significativamente o fator de reprodução do nematoide das galhas (P<0,05) em valores que variaram entre 20 e 49%. Contudo, além de suprimir a multiplicação do patógeno, o isolado F78 (Streptomyces sp.) promoveu aumento do peso de raízes, maiores índices de clorofila e conteúdo das enzimas de resistência peroxidades e polifenol-oxidades, e, redução na concentração de fenóis das figueiras microbiolizadas. Nesse sentido, a condução de trabalhos adicionais nesse patossistema pode possibilitar a melhor compreensão dos mecanismos de atuação das bactérias testadas no biocontrole de M. incognita, além de fornecer informações adicionais para a implementação dessa técnica em um programa de manejo integrado do nematoide das galhas.The fig tree is economically important for the social role it plays in the context of family farming. However, its economic viability can be compromised in infested areas by root-knot nematode (Meloidogyne incognita) due to lack of effective and available control measures. Therefore, the insertion of the biological control on the integrated management of this pest constitutes an important strategy. The rhizobacteria are considered promising biocontrol agents for promoting plant growth and or inhibit the parasitic action of plant-parasitic nematodes in the host plants. So, the aim of this study was to evaluate the performance of 14 bacterial isolates from the rhizosphere of fig and shale rocks in biocontrol of M. incognita in fig. Seedlings of fig plants of cv. 'Roxo de Valinhos' were microbiolized with these bacterial isolates and they were transplanted in soil naturally infested with M. incognita subsequently. Seven isolates (F08, F25, F71, F76, F78, FB34 and FB59) reduced the reproduction factor of the root-knot nematode (P <0.05) at rate ranging between 20 and 49%. Besides to suppress the pathogen reproduction, the isolated F78 (Streptomyces sp.) promoting increasing of root weight, higher chlorophyll contents and content peroxidases and polyphenol oxidases resistance enzymes, and reduction of the phenol concentration of microbiolized fig plants. In this sense, conducting further studies in this pathosystem can enable a better understanding of the action mechanisms of the bacteria tested in the biocontrol of M. incognita, as well as providing additional information for the implementation of this technique in an integrated management program of root-knot nematode.Facultad de Ciencias Agrarias y Forestale