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1.
Lab Chip ; 24(1): 113-126, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38047296

RESUMO

We present tuna-step, a novel microfluidic module based on step emulsification that allows for reliable generation of droplets of different sizes. Until now, sizes of droplets generated with step emulsification were hard-wired into the geometry of the step emulsification nozzle. To overcome this, we incorporate a thin membrane underneath the step nozzle that can be actuated by pressure, enabling the tuning of the nozzle size on-demand. By controllably reducing the height of the nozzle, we successfully achieved a three-order-of-magnitude variation in droplet volume without adjusting the flow rates of the two phases. We developed and applied a new hydrophilic surface modification, that ensured long-term stability and prevented swelling of the device when generating oil-in-water droplets. Our system produced functionally graded soft materials with adjustable porosity and material content. By combining our microfluidic device with a custom 3D printer, we generated and extruded oil-in-water emulsions in an agarose gel bath, creating unique self-standing 3D hydrogel structures with porosity decoupled from flow rate and with composition gradients of external phases. We upscaled tuna-step by setting 14 actuatable nozzles in parallel, offering a step-emulsification-based single chip solution that can accommodate various requirements in terms of throughput, droplet volumes, flow rates, and surface chemistry.

2.
Int J Biol Macromol ; 246: 125669, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37406901

RESUMO

Tissue engineering research has undergone to a revolutionary improvement, thanks to technological advancements, such as the introduction of bioprinting technologies. The ability to develop suitable customized biomaterial inks/bioinks, with excellent printability and ability to promote cell proliferation and function, has a deep impact on such improvements. In this context, printing inks based on chitosan and its derivatives have been instrumental. Thus, the current review aims at providing a comprehensive overview on chitosan-based materials as suitable inks for 3D/4D (bio)printing and their applicability in creating advanced drug delivery platforms and tissue engineered constructs. Furthermore, relevant strategies to improve the mechanical and biological performances of this biomaterial are also highlighted.


Assuntos
Quitosana , Engenharia Tecidual , Impressão Tridimensional , Materiais Biocompatíveis , Sistemas de Liberação de Medicamentos , Alicerces Teciduais
3.
Biofabrication ; 15(4)2023 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-37473749

RESUMO

In this work, we present an innovative, high-throughput rotary wet-spinning biofabrication method for manufacturing cellularized constructs composed of highly-aligned hydrogel fibers. The platform is supported by an innovative microfluidic printing head (MPH) bearing a crosslinking bath microtank with a co-axial nozzle placed at the bottom of it for the immediate gelation of extruded core/shell fibers. After a thorough characterization and optimization of the new MPH and the fiber deposition parameters, we demonstrate the suitability of the proposed system for thein vitroengineering of functional myo-substitutes. The samples produced through the described approach were first characterizedin vitroand then used as a substrate to ascertain the effects of electro-mechanical stimulation on myogenic maturation. Of note, we found a characteristic gene expression modulation of fast (MyH1), intermediate (MyH2), and slow (MyH7) twitching myosin heavy chain isoforms, depending on the applied stimulation protocol. This feature should be further investigated in the future to biofabricate engineered myo-substitutes with specific functionalities.


Assuntos
Bioimpressão , Hidrogéis , Hidrogéis/química , Desenvolvimento Muscular/genética , Microfluídica , Bioimpressão/métodos , Impressão Tridimensional , Engenharia Tecidual/métodos , Alicerces Teciduais/química
4.
Adv Healthc Mater ; 12(23): e2300443, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37353904

RESUMO

3D bioprinting has developed tremendously in the last couple of years and enables the fabrication of simple, as well as complex, tissue models. The international space agencies have recognized the unique opportunities of these technologies for manufacturing cell and tissue models for basic research in space, in particular for investigating the effects of microgravity and cosmic radiation on different types of human tissues. In addition, bioprinting is capable of producing clinically applicable tissue grafts, and its implementation in space therefore can support the autonomous medical treatment options for astronauts in future long term and far-distant space missions. The article discusses opportunities but also challenges of operating different types of bioprinters under space conditions, mainly in microgravity. While some process steps, most of which involving the handling of liquids, are challenging under microgravity, this environment can help overcome problems such as cell sedimentation in low viscous bioinks. Hopefully, this publication will motivate more researchers to engage in the topic, with publicly available bioprinting opportunities becoming available at the International Space Station (ISS) in the imminent future.


Assuntos
Bioimpressão , Radiação Cósmica , Voo Espacial , Ausência de Peso , Humanos , Impressão Tridimensional
5.
Vaccine ; 41(23): 3518-3524, 2023 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-37142462

RESUMO

BACKGROUND: Vaccination is the best mode of protection against tick-borne encephalitis (TBE) and its sequelae. The duration of protection and the optimal interval of repeat booster doses are still debated. The current study evaluated the persistence of the antibody response 11-15 years after a first booster vaccination following different primary vaccination schedules with a TBE vaccine (Encepur Adults, manufactured by Bavarian Nordic, previously by GSK). METHODS: This phase IV, open-label, mono-centric extension study enrolled adults who had received (at ≥ 12 years of age) primary vaccination with one of three randomly assigned TBE vaccine schedules (rapid [group R], conventional [group C], or accelerated conventional schedule [group A]) followed by a booster dose 3 years later. The antibody response was measured annually from 11 to 15 years post-booster using a TBE virus neutralization test (NT). An NT titer of ≥ 10 was considered as a clinically meaningful threshold and surrogate for protection. RESULTS: In total, 194 participants were enrolled and included in the per-protocol set; 188 completed the study. The percentage of participants with an NT titer ≥ 10 was 100% in group R and 99.0% in group A at all visits and ranged from 100% (year 11) to 95.8% (year 15) in group C. NT geometric mean titers were similar in the three study groups (181-267 in group R, 142-227 in group C, 141-209 in group A). NT geometric mean titers also remained high among participants ≥ 50 years old (98-206) and ≥ 60 years old (91-191) across study groups and time points. CONCLUSIONS: This study showed neutralizing antibody persistence for at least 15 years after a first booster dose of the Encepur Adults TBE vaccine in all age groups evaluated, regardless of which primary vaccination schedule was given to adolescents or adults. Trialregistry: ClinicalTrials.gov: NCT03294135.


Assuntos
Encefalite Transmitida por Carrapatos , Vacinas Virais , Adolescente , Adulto , Pré-Escolar , Humanos , Pessoa de Meia-Idade , Anticorpos Antivirais , Encefalite Transmitida por Carrapatos/prevenção & controle , Seguimentos , Esquemas de Imunização , Imunização Secundária , Vacinação
6.
Plant J ; 113(4): 851-865, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36597651

RESUMO

Auxin Response Factor 8 plays a key role in late stamen development: its splice variants ARF8.4 and ARF8.2 control stamen elongation and anther dehiscence. Here, we characterized the role of ARF8 isoforms in pollen fertility. By phenotypic and ultrastructural analysis of arf8-7 mutant stamens, we found defects in pollen germination and viability caused by alterations in exine structure and pollen coat deposition. Furthermore, tapetum degeneration, a prerequisite for proper pollen wall formation, is delayed in arf8-7 anthers. In agreement, the genes encoding the transcription factors TDF1, AMS, MS188 and MS1, required for exine and pollen coat formation, and tapetum development, are downregulated in arf8-7 stamens. Consistently, the sporopollenin content is decreased, and the expression of sporopollenin synthesis/transport and pollen coat protein biosynthetic genes, regulated by AMS and MS188, is reduced. Inducible expression of the full-length isoform ARF8.1 in arf8-7 inflorescences complements the pollen (and tapetum) phenotype and restores the expression of the above transcription factors. Chromatin immunoprecipitation-quantitative polymerase chain reaction assay revealed that ARF8.1 directly targets the promoters of TDF1, AMS and MS188. In conclusion, the ARF8.1 isoform controls pollen and tapetum development acting directly on the expression of TDF1, AMS and MS188, which belong to the pollen/tapetum genetic pathway.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Parede Celular/metabolismo , Fator VIII/genética , Fator VIII/metabolismo , Flores/genética , Regulação da Expressão Gênica de Plantas , Ácidos Indolacéticos/metabolismo , Pólen , Isoformas de Proteínas/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
7.
Pharm Stat ; 22(3): 570-576, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36707656

RESUMO

Here we present as case study how re-randomization tests were performed in two randomized, controlled clinical trials as sensitivity analyses, as recommended by the United States Food and Drug Administration in the context of adaptive randomization. This was done to confirm primary conclusions on immunological noninferiority of an investigational new fully liquid presentation of a quadrivalent cross-reacting material conjugate meningococcal vaccine (MenACWY-CRM), over its licensed lyophilized/liquid presentation. In two phase 2b studies (Study #1: NCT03652610; Study #2: NCT03433482), noninferiority of the fully liquid presentation of MenACWY-CRM to the licensed presentation was assessed and demonstrated for immune responses against meningococcal serogroup A (MenA), the only vaccine component modified from lyophilized to liquid in the new presentation. The original vaccine assignment algorithm, with a minimization procedure accounting for center or center within age strata, was used to re-randomize participants belonging to the fully liquid and licensed vaccine groups while keeping antibody responses, covariates and entry order as observed. Test statistics under re-randomization were generated according to the ANCOVA model used in the primary analysis. To confirm immunological noninferiority following re-randomization, the corresponding p-values had to be <0.025. For both studies and all primary objective evaluations, the re-randomization p-values were well below 0.025 (0.0004 for Study #1; 0.0001 for the two co-primary endpoints in Study #2). Re-randomization tests performed to comply with a regulatory request confirmed the primary conclusions of immunological noninferiority for the MenA of the fully liquid compared to the licensed vaccine presentation.


Assuntos
Vacinas Meningocócicas , Neisseria meningitidis , Estados Unidos , Humanos , Distribuição Aleatória , Anticorpos Antibacterianos
8.
Drug Saf ; 46(1): 99-108, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36369456

RESUMO

INTRODUCTION: The currently licensed quadrivalent MenACWY-CRM conjugate vaccine presentation consists of two vials (lyophilized MenA and liquid MenCWY) to be reconstituted before injection. A new fully liquid, single-vial formulation has been developed to simplify administration and prevent reconstitution errors. We present pooled safety data from two randomized, controlled, observer-blind phase 2b clinical trials, in which the fully liquid presentation was compared with the licensed presentation. METHODS: This is a post hoc analysis of two studies, in which safety data from participants aged 10-40 years who received one dose of either liquid MenACWY-CRM (1337 participants; MenACWY liquid group) or licensed MenACWY-CRM (1332 participants; MenACWY licensed group) were pooled. Frequencies were calculated for solicited adverse events (AEs) during 7 days post-vaccination and unsolicited AEs, including medically attended AEs and serious AEs (SAEs), during the 6-month safety follow-up period. Analysis results are presented by vaccine group, overall and by age category (10-17 and 18-40 years). RESULTS: Overall, AEs solicited for collection during the first 7 days after vaccination were reported by similar percentages of participants (69.2%, MenACWY liquid; 68.2%, MenACWY licensed), and were generally mild/moderate in intensity. Solicited local AEs were reported by 46.0% of the MenACWY liquid group and 43.5% of the MenACWY licensed group and solicited systemic AEs by 55.2 and 54.1%, respectively. During the 6-month post-vaccination period, unsolicited AEs were reported by 32.2 and 31.2% of the MenACWY liquid group and MenACWY licensed group, respectively, and medically attended AEs by 18.6 and 17.3%, respectively. Overall, 14 participants in each group (1.0 and 1.1%, respectively) reported SAEs, none of which was considered vaccine-related by the investigator. The safety profiles of both MenACWY-CRM presentations were similar for each age group and overall. CONCLUSIONS: This pooled analysis shows the safety profile of fully liquid MenACWY-CRM is comparable with that of the currently licensed vaccine presentation. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov Identifiers: NCT03652610 (August 29, 2018), NCT03433482 (14 February 2018).


Assuntos
Vacinação , Humanos , Vacinação/métodos
9.
Biomater Sci ; 11(9): 2988-3015, 2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-36468579

RESUMO

Liver is one of the most important and complex organs in the human body, being characterized by a sophisticated microarchitecture and responsible for key physiological functions. Despite its remarkable ability to regenerate, acute liver failure and chronic liver diseases are major causes of morbidity and mortality worldwide. Therefore, understanding the molecular mechanisms underlying such liver disorders is critical for the successful development of novel therapeutics. In this frame, preclinical animal models have been portrayed as the most commonly used tool to address such issues. However, due to significant species differences in liver architecture, regenerative capacity, disease progression, inflammatory markers, metabolism rates, and drug response, animal models cannot fully recapitulate the complexity of human liver metabolism. As a result, translational research to model human liver diseases and drug screening platforms may yield limited results, leading to failure scenarios. To overcome this impasse, over the last decade, 3D human liver in vitro models have been proposed as an alternative to pre-clinical animal models. These systems have been successfully employed for the investigation of the etiology and dynamics of liver diseases, for drug screening, and - more recently - to design patient-tailored therapies, resulting in potentially higher efficacy and reduced costs compared to other methods. Here, we review the most recent advances in this rapidly evolving field with particular attention to organoid cultures, liver-on-a-chip platforms, and engineered scaffold-based approaches.


Assuntos
Falência Hepática Aguda , Organoides , Animais , Humanos , Avaliação Pré-Clínica de Medicamentos/métodos , Modelos Animais
10.
Front Res Metr Anal ; 7: 927383, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36407915

RESUMO

The study presented in this article analyzed qualitative and quantitative data on the performance of the European Maritime and Fisheries Fund (EMFF) based on the information reported in the European Union (EU) List of Operations updated to December 2020. Each EMFF measure and type of financial support were divided into three broad categories of subsidies according to their main objectives and scope: capacity enhancing, beneficial, or ambiguous. Capacity enhancing is defined as funds that could incentive overcapacity or overfishing. Beneficial refers to subsidies that have a positive impact on fish stocks and the environment. Ambiguous subsidies correspond to funds that may lead to positive or negative impacts on the environment depending on how they are designed and implemented. The assessment revealed the asymmetric distribution of EMFF resources in the Mediterranean region. In the six member states investigated, EMFF support is concentrated on a limited number of more easily accessible measures from an administrative and financial point of view. Most of the allocated funds are classified as capacity enhancing; other frequently used measures are in the ambiguous category. Small-scale vessels using static gear and accounting for the largest part of the Mediterranean fleets received a negligible share of specific funds for promoting environmentally sustainable fisheries. Most investments are concentrated on larger trawlers to support the temporary cessation of fishing activities and scrapping operations. Further qualitative analysis based on the findings and recommendations of previous reports evaluating the use of EMFF as well as interviews with beneficiaries highlighted that complex administrative procedures and legal uncertainty in the interpretations of some articles of the EMFF regulations are the main reasons for the asymmetric performance of the EMFF measures. The dispersion of responsibilities among European, national and regional authorities, and an evident lack of coordination among them are the main shortcomings that were identified. The limited use of advance payments, the lack of capacity, and technical assistance and obstacles to accessing financial instruments have penalized most of the projects that are focused on innovation, diversification, and environmental sustainability.

11.
J Mater Chem B ; 10(39): 7905-7923, 2022 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-36102133

RESUMO

Degree of oxygenation is one of the important parameters governing various processes, including cell proliferation, angiogenesis, extracellular matrix production, and even combating the microbial burden at the wound site, all of which are essential for tissue function restoration and integrity. Inadequate oxygenation interrupts the normal healing process and delays patient recovery. The present article overviews the role of oxygen in the wound healing process and different oxygenation therapies that have been applied for healing dermal wounds. Furthermore, we critically assessed various challenges and opportunities in the near future for adequate and controlled oxygen delivery at the wounded site with minimal toxicity.


Assuntos
Oxigênio , Cicatrização , Proliferação de Células , Matriz Extracelular , Humanos
12.
Materials (Basel) ; 15(1)2022 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-35009484

RESUMO

Nanozymes, a type of nanomaterial with enzyme-like properties, are a promising alternative to natural enzymes. In particular, transition metal dichalcogenides (TMDCs, with the general formula MX2, where M represents a transition metal and X is a chalcogen element)-based nanozymes have demonstrated exceptional potential in the healthcare and diagnostic sectors. TMDCs have different enzymatic properties due to their unique nano-architecture, high surface area, and semiconducting properties with tunable band gaps. Furthermore, the compatibility of TMDCs with various chemical or physical modification strategies provide a simple and scalable way to engineer and control their enzymatic activity. Here, we discuss recent advances made with TMDC-based nanozymes for biosensing and therapeutic applications. We also discuss their synthesis strategies, various enzymatic properties, current challenges, and the outlook for future developments in this field.

13.
ACS Biomater Sci Eng ; 8(2): 379-405, 2022 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-35084836

RESUMO

The functional capabilities of skeletal muscle are strongly correlated with its well-arranged microstructure, consisting of parallelly aligned myotubes. In case of extensive muscle loss, the endogenous regenerative capacity is hindered by scar tissue formation, which compromises the native muscle structure, ultimately leading to severe functional impairment. To address such an issue, skeletal muscle tissue engineering (SMTE) attempts to fabricate in vitro bioartificial muscle tissue constructs to assist and accelerate the regeneration process. Due to its dynamic nature, SMTE strategies must employ suitable biomaterials (combined with muscle progenitors) and proper 3D architectures. In light of this, 3D fiber-based strategies are gaining increasing interest for the generation of hydrogel microfibers as advanced skeletal muscle constructs. Indeed, hydrogels possess exceptional biomimetic properties, while the fiber-shaped morphology allows for the creation of geometrical cues to guarantee proper myoblast alignment. In this review, we summarize commonly used hydrogels in SMTE and their main properties, and we discuss the first efforts to engineer hydrogels to guide myoblast anisotropic orientation. Then, we focus on presenting the main hydrogel fiber-based techniques for SMTE, including molding, electrospinning, 3D bioprinting, extrusion, and microfluidic spinning. Furthermore, we describe the effect of external stimulation (i.e., mechanical and electrical) on such constructs and the application of hydrogel fiber-based methods on recapitulating complex skeletal muscle tissue interfaces. Finally, we discuss the future developments in the application of hydrogel microfibers for SMTE.


Assuntos
Bioimpressão , Hidrogéis , Bioimpressão/métodos , Hidrogéis/química , Hidrogéis/farmacologia , Músculo Esquelético , Mioblastos , Engenharia Tecidual/métodos
14.
Hum Vaccin Immunother ; 18(1): 1981085, 2022 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-34614379

RESUMO

A fully liquid MenACWY-CRM vaccine presentation has been developed, modifying the meningococcal serogroup A (MenA) component from lyophilized to liquid. The safety and immunogenicity of the liquid presentation at the end of the intended shelf-life (aged for 24 or 30 months) were compared to the licensed lyophilized/liquid presentation. This multicenter, randomized (1:1), observer-blind, phase 2b study (NCT03433482) enrolled adolescents and young adults (age 10-40 years). In part 1, 844 participants received one dose of liquid presentation stored for approximately 24 months or licensed presentation. In part 2, 846 participants received one dose of liquid presentation stored for approximately 30 months or licensed presentation. After storage, the MenA free saccharide (FS) level was approximately 25% and O-acetylation was approximately 45%. The primary objective was to demonstrate non-inferiority of the liquid presentation to licensed presentation, as measured by human serum bactericidal assay (hSBA) geometric mean titers (GMTs) against MenA, 1-month post-vaccination. Immune responses against each vaccine serogroup were similar between groups. Between-group ratios of hSBA GMTs for MenA were 1.21 (part 1) and 1.11 (part 2), with two-sided 95% confidence interval lower limits (0.94 and 0.87, respectively) greater than the prespecified non-inferiority margin (0.5), thus meeting the primary study objective. No safety concerns were identified. Despite reduced O-acetylation of MenA and increased FS content, serogroup-specific immune responses induced by the fully liquid presentation were similar to those induced by the licensed MenACWY-CRM vaccine, with non-inferior anti-MenA responses. The safety profiles of the vaccine presentations were similar.


Assuntos
Infecções Meningocócicas , Vacinas Meningocócicas , Neisseria meningitidis , Adolescente , Adulto , Idoso , Anticorpos Antibacterianos , Criança , Humanos , Infecções Meningocócicas/prevenção & controle , Sorogrupo , Vacinas Conjugadas , Adulto Jovem
15.
Vaccine ; 39(45): 6628-6636, 2021 10 29.
Artigo em Inglês | MEDLINE | ID: mdl-34635373

RESUMO

BACKGROUND: The currently licensed quadrivalent MenACWY-CRM conjugate vaccine presentation consists of two vials (lyophilised MenA and liquid MenCWY) to be reconstituted before injection. A new fully liquid formulation in a single vial has been developed to further improve the vaccine presentation. Since the MenA structure is subject to hydrolytic degradation, this study was conducted to compare the immunogenicity and safety of the investigational MenACWY-CRM liquid vaccine with the licensed vaccine. METHODS: In this multicentre, randomised, controlled, observer-blind, phase 2b study, 979 healthy adults were administered a single dose of MenACWY-CRM liquid presentation or the currently licensed MenACWY-CRM vaccine. MenA free saccharide generation was accelerated to approximately 30% in the liquid presentation and MenA polysaccharide O-acetylation was reduced to approximately 40%, according to a controlled procedure. Immunological non-inferiority of the MenACWY-CRM liquid to the licensed vaccine, as measured by human serum bactericidal assay (hSBA) geometric mean titres (GMTs) against MenA 1 month post-vaccination, was the primary study objective. Safety assessment was among the secondary objectives. RESULTS: Immune responses against each serogroup were similar between the two vaccine groups and was non-inferior for MenA. Adjusted hSBA GMTs for MenA were 185.16 and 211.33 for the MenACWY-CRM liquid presentation and currently licensed vaccine presentation, respectively. The between-group ratio of hSBA GMTs for MenA was 0.88, with a two-sided 95% confidence interval lower limit of 0.64, greater than the prespecified non-inferiority margin of 0.5, thus meeting the primary study objective. Both vaccines were well tolerated. No serious adverse events were considered related to vaccination. CONCLUSIONS: The levels of MenA free saccharide and polysaccharide O-acetylation did not affect the immunogenicity of the fully liquid presentation, which was demonstrated to be non-inferior to the immunogenicity of the currently licensed MenACWY-CRM vaccine against MenA. The immunogenicity, reactogenicity and safety profiles of the two vaccine presentations were similar.


Assuntos
Infecções Meningocócicas , Vacinas Meningocócicas , Adulto , Anticorpos Antibacterianos , Humanos , Vacinação , Vacinas Conjugadas
16.
Front Bioeng Biotechnol ; 9: 732130, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34604190

RESUMO

In the last decades, biomedical research has significantly boomed in the academia and industrial sectors, and it is expected to continue to grow at a rapid pace in the future. An in-depth analysis of such growth is not trivial, given the intrinsic multidisciplinary nature of biomedical research. Nevertheless, technological advances are among the main factors which have enabled such progress. In this review, we discuss the contribution of two state-of-the-art technologies-namely biofabrication and organ-on-a-chip-in a selection of biomedical research areas. We start by providing an overview of these technologies and their capacities in fabricating advanced in vitro tissue/organ models. We then analyze their impact on addressing a range of current biomedical challenges. Ultimately, we speculate about their future developments by integrating these technologies with other cutting-edge research fields such as artificial intelligence and big data analysis.

17.
Small Methods ; 5(9): e2100402, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34514087

RESUMO

In recent years, the main quest of science has been the pioneering of the groundbreaking biomedical strategies needed for achieving a personalized medicine. Ribonucleic acids (RNAs) are outstanding bioactive macromolecules identified as pivotal actors in regulating a wide range of biochemical pathways. The ability to intimately control the cell fate and tissue activities makes RNA-based drugs the most fascinating family of bioactive agents. However, achieving a widespread application of RNA therapeutics in humans is still a challenging feat, due to both the instability of naked RNA and the presence of biological barriers aimed at hindering the entrance of RNA into cells. Recently, material scientists' enormous efforts have led to the development of various classes of nanostructured carriers customized to overcome these limitations. This work systematically reviews the current advances in developing the next generation of drugs based on nanotechnology-assisted RNA delivery. The features of the most used RNA molecules are presented, together with the development strategies and properties of nanostructured vehicles. Also provided is an in-depth overview of various therapeutic applications of the presented systems, including coronavirus disease vaccines and the newest trends in the field. Lastly, emerging challenges and future perspectives for nanotechnology-mediated RNA therapies are discussed.


Assuntos
COVID-19 , Ácidos Nucleicos , Vacinas contra COVID-19/uso terapêutico , Sistemas de Liberação de Medicamentos , Humanos , Nanotecnologia , Ácidos Nucleicos/uso terapêutico , Preparações Farmacêuticas , RNA/genética
18.
J Mater Chem B ; 9(37): 7608-7632, 2021 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-34586145

RESUMO

Nature's material systems during evolution have developed the ability to respond and adapt to environmental stimuli through the generation of complex structures capable of varying their functions across direction, distances and time. 3D printing technologies can recapitulate structural motifs present in natural materials, and efforts are currently being made on the technological side to improve printing resolution, shape fidelity, and printing speed. However, an intrinsic limitation of this technology is that printed objects are static and thus inadequate to dynamically reshape when subjected to external stimuli. In recent years, this issue has been addressed with the design and precise deployment of smart materials that can undergo a programmed morphing in response to a stimulus. The term 4D printing was coined to indicate the combined use of additive manufacturing, smart materials, and careful design of appropriate geometries. In this review, we report the recent progress in the design and development of smart materials that are actuated by different stimuli and their exploitation within additive manufacturing to produce biomimetic structures with important repercussions in different but interrelated biomedical areas.


Assuntos
Impressão Tridimensional , Materiais Inteligentes/química , Biomimética , Portadores de Fármacos/química , Hidrogéis/química , Robótica , Estereolitografia , Engenharia Tecidual , Dispositivos Eletrônicos Vestíveis
19.
Sensors (Basel) ; 21(15)2021 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34372345

RESUMO

In this contribution, three methodologies based on temperature-sensitive paint (TSP) data were further developed and applied for the optical determination of the critical locations of flow separation and reattachment in compressible, high Reynolds number flows. The methodologies rely on skin-friction extraction approaches developed for low-speed flows, which were adapted in this work to study flow separation and reattachment in the presence of shock-wave/boundary-layer interaction. In a first approach, skin-friction topological maps were obtained from time-averaged surface temperature distributions, thus enabling the identification of the critical lines as converging and diverging skin-friction lines. In the other two approaches, the critical lines were identified from the maps of the propagation celerity of temperature perturbations, which were determined from time-resolved TSP data. The experiments were conducted at a freestream Mach number of 0.72 and a chord Reynolds number of 9.7 million in the Transonic Wind Tunnel Göttingen on a VA-2 supercritical airfoil model, which was equipped with two exchangeable TSP modules specifically designed for transonic, high Reynolds number tests. The separation and reattachment lines identified via the three different TSP-based approaches were shown to be in mutual agreement, and were also found to be in agreement with reference experimental and numerical data.

20.
Int J Mol Sci ; 22(11)2021 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-34070750

RESUMO

The immune system is a fine modulator of the tumor biology supporting or inhibiting its progression, growth, invasion and conveys the pharmacological treatment effect. Tumors, on their side, have developed escaping mechanisms from the immune system action ranging from the direct secretion of biochemical signals to an indirect reaction, in which the cellular actors of the tumor microenvironment (TME) collaborate to mechanically condition the extracellular matrix (ECM) making it inhospitable to immune cells. TME is composed of several cell lines besides cancer cells, including tumor-associated macrophages, cancer-associated fibroblasts, CD4+ and CD8+ lymphocytes, and innate immunity cells. These populations interface with each other to prepare a conservative response, capable of evading the defense mechanisms implemented by the host's immune system. The presence or absence, in particular, of cytotoxic CD8+ cells in the vicinity of the main tumor mass, is able to predict, respectively, the success or failure of drug therapy. Among various mechanisms of immunescaping, in this study, we characterized the modulation of the phenotypic profile of CD4+ and CD8+ cells in resting and activated states, in response to the mechanical pressure exerted by a three-dimensional in vitro system, able to recapitulate the rheological and stiffness properties of the tumor ECM.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Matriz Extracelular/imunologia , Regulação Neoplásica da Expressão Gênica/imunologia , Evasão Tumoral , Microambiente Tumoral/imunologia , 5'-Nucleotidase/genética , 5'-Nucleotidase/imunologia , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD8-Positivos/patologia , Fibroblastos Associados a Câncer/imunologia , Fibroblastos Associados a Câncer/patologia , Técnicas de Cultura de Células , Módulo de Elasticidade , Matriz Extracelular/química , Feminino , Proteínas Ligadas por GPI/genética , Proteínas Ligadas por GPI/imunologia , Humanos , Hidrogéis/química , Interferon gama/genética , Interferon gama/imunologia , Ativação Linfocitária , Mecanotransdução Celular , Modelos Biológicos , NF-kappa B/genética , NF-kappa B/imunologia , Fenótipo , Cultura Primária de Células , Receptor de Morte Celular Programada 1/genética , Receptor de Morte Celular Programada 1/imunologia , Reologia , Fator de Transcrição Sp1/genética , Fator de Transcrição Sp1/imunologia , Fator de Transcrição RelA/genética , Fator de Transcrição RelA/imunologia , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/imunologia , Neoplasias de Mama Triplo Negativas/patologia , Microambiente Tumoral/genética , Macrófagos Associados a Tumor/imunologia , Macrófagos Associados a Tumor/patologia
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