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1.
Int J Sports Med ; 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-38925152

RESUMO

Jump actions are common in several sports, and their performance is related to a myriad of biomechanical and physiological factors, with links to athletic performance and imbalances. Currently, a valid, field-based, easy-to-use tool to assess the quality of an explosive jump movement, similar to the required sports movements, is unavailable. Thus, the present study aimed to design and validate a field-based, easy-to-use tool that can be used to assess the quality of movement during an explosive single-leg countermovement jump (SL-CMJ). Ten experts participated in the content validation process for the checklist, including checking item relevance, definition accuracy, and scoring adequacy. Content validity was measured using the Aikens V format. The checklist included the items "Foot orientation," "Knee valgus/varus," "Internal/external hip flexed orientation," "Pelvis tilt," "Thorax tilt," "Thorax rotation," "Foot pronation/supination," "Asymmetrical hip," and "Lumbo-pelvic association". The items achieved a 0.60-0.99 in relevance, 0.70-1.00 in definition accuracy, and 0.80-0.83 in scoring adequacies in the Aikens V proof. The results from the context validation process suggest that the tool may be appropriate to assess athletes' quality of explosive movement. Furthermore, the results derived from such assessments may help to design better and safer training interventions.

2.
Biotechnol Lett ; 43(6): 1155-1161, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33638746

RESUMO

OBJECTIVE: To develop a method for the efficient assembly of viral or multimeric proteins into virus-like particles (VLP) or other macro structures. RESULTS: Protein monomers were assembled by eliminating calcium ions through precipitation. The model protein, rotavirus VP6, assembled into stable, long nanotubes with better quality than the assemblies obtained directly from cell culture. Nanotube length was directly proportional to the initial concentration of VP6 monomers, in accordance with the classic nucleation theory of capsid assembly. The quality of the obtained assemblies was confirmed when the nanotubes were functionalized with metals, yielding unique nanobiomaterials. Assembly efficiency was improved in comparison with other previously proposed methods. CONCLUSIONS: The novel method presented here is simpler and faster than other reported methods for the assembly and disassembly of viral proteins, a step needed for most applications.


Assuntos
Antígenos Virais/química , Antígenos Virais/metabolismo , Proteínas do Capsídeo/química , Proteínas do Capsídeo/metabolismo , Rotavirus/metabolismo , Cálcio/química , Precipitação Química , Nanotubos/química , Multimerização Proteica
3.
Nanotechnology ; 31(13): 132002, 2020 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-31770746

RESUMO

Biomedical applications increasingly require fully characterized new nanomaterials. There is strong evidence showing that nanomaterials not only interact with cells passively but also actively, mediating essential molecular processes for the regulation of cellular functions, but we are only starting to understand the mechanisms of those interactions. Systematic studies about cell behavior as a response to specific nanoparticle properties are scarce in the literature even when they are necessary for the rational design of medical nanodevices. Information in the literature shows that the physicochemical properties determine the bioactivity, biocompatibility, and safety of nanomaterials. The information available regarding the interaction and responses of cells to nanomaterials has not been analyzed and discussed in a single document. Hence, in this review, we present the latest advances about cellular responses to nanomaterials and integrate the available information into concrete considerations for the development of innovative, efficient, specific and, more importantly, safe biomedical nanodevices. We focus on how physicochemical nanoparticle properties (size, chemical surface, shape, charge, and topography) influence cell behavior in a first attempt to provide a practical guide for designing medical nanodevices, avoiding common experimental omissions that may lead to data misinterpretation. Finally, we emphasize the importance of the systematic study of nano-bio interactions to acquire sufficient reproducible information that allows accurate control of cell behavior based on tuning of nanomaterial properties. This information is useful to guide the design of specific nanodevices and nanomaterials to elicit desired cell responses, like targeting, drug delivery, cell attachment, differentiation, etc, or to avoid undesired side effects.


Assuntos
Desenho de Equipamento/métodos , Nanoestruturas/química , Animais , Comunicação Celular , Sistemas de Liberação de Medicamentos , Humanos , Tamanho da Partícula , Propriedades de Superfície
4.
Front Pharmacol ; 15: 1412420, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39081952

RESUMO

Fluoxetine, the prototypical selective serotonin reuptake inhibitor (SSRI), is widely used to treat major depressive disorder (MDD) and a variety of other central nervous system conditions, primarily due to its established clinical safety profile. Although its efficacy in treating depression is well-recognized, the impact of fluoxetine on cognitive functions remains inconsistent and elusive. In this review, we first examine the well-substantiated biological mechanisms underlying fluoxetine's antidepressant effects, which include serotonin reuptake inhibition and activation of TrkB receptors-key to brain-derived neurotrophic factor (BDNF) signaling. Subsequently, we delve into the cognitive side effects observed in both preclinical and clinical studies, affecting domains such as memory, attention, and executive functions. While certain studies indicate cognitive improvements in patients with underlying disorders, there is also evidence of negative effects, influenced by variables like gender, duration of treatment, age, disease pathology, and the specifics of cognitive testing. Significantly, the negative cognitive outcomes reported in preclinical research often involve healthy, non-diseased animals. This review underscores the necessity for heightened caution in fluoxetine prescription and further investigation into its potentially detrimental cognitive effects, even when used prophylactically.

5.
Heliyon ; 10(5): e26641, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38444512

RESUMO

Additive Manufacturing (AM) has recently demonstrated significant medical progress. Due to advancements in materials and methodologies, various processes have been developed to cater to the medical sector's requirements, including bioprinting and 4D, 5D, and 6D printing. However, only a few studies have captured these emerging trends and their medical applications. Therefore, this overview presents an analysis of the advancements and achievements obtained in AM for the medical industry, focusing on the principal trends identified in the annual report of AM3DP.

6.
Pharmaceutics ; 15(9)2023 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-37765229

RESUMO

The interest in plant-derived virus-like particles (pVLPs) for the design of a new generation of nanocarriers is based on their lack of infection for humans, their immunostimulatory properties to fight cancer cells, and their capability to contain and release cargo molecules. Asparaginase (ASNase) is an FDA-approved drug to treat acute lymphoblastic leukemia (LLA); however, it exhibits high immunogenicity which often leads to discontinuation of treatment. In previous work, we encapsulated ASNase into bacteriophage P22-based VLPs through genetic-directed design to form the ASNase-P22 nanobioreactors. In this work, a commercial ASNase was encapsulated into brome mosaic virus-like particles (BMV-VLPs) to form stable ASNase-BMV nanobioreactors. According to our results, we observed that ASNase-BMV nanobioreactors had similar cytotoxicity against MOLT-4 and Reh cells as the commercial drug. In vivo assays showed a higher specific anti-ASNase IgG response in BALB/c mice immunized with ASNase encapsulated into BMV-VLPs compared with those immunized with free ASNase. Nevertheless, we also detected a high and specific IgG response against BMV capsids on both ASNase-filled capsids (ASNase-BMV) and empty BMV capsids. Despite the fact that our in vivo studies showed that the BMV-VLPs stimulate the immune response either empty or with cargo proteins, the specific cytotoxicity against leukemic cells allows us to propose ASNase-BMV as a potential novel formulation for LLA treatment where in vitro and in vivo evidence of functionality is provided.

7.
Pharmaceutics ; 15(6)2023 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-37376198

RESUMO

Neural tissue engineering presents a compelling technological breakthrough in restoring brain function, holding immense promise. However, the quest to develop implantable scaffolds for neural culture that fulfill all necessary criteria poses a remarkable challenge for material science. These materials must possess a host of desirable characteristics, including support for cellular survival, proliferation, and neuronal migration and the minimization of inflammatory responses. Moreover, they should facilitate electrochemical cell communication, display mechanical properties akin to the brain, emulate the intricate architecture of the extracellular matrix, and ideally allow the controlled release of substances. This comprehensive review delves into the primary requisites, limitations, and prospective avenues for scaffold design in brain tissue engineering. By offering a panoramic overview, our work aims to serve as an essential resource, guiding the creation of materials endowed with bio-mimetic properties, ultimately revolutionizing the treatment of neurological disorders by developing brain-implantable scaffolds.

8.
ChemistryOpen ; 12(5): e202200241, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37226371

RESUMO

Copper oxide nanoparticles (CuO-NPs) were functionalized with specific antibodies to target their antibacterial activity against Gram-positive or Gram-negative bacteria. The CuO-NPs were covalently functionalized to cover their surface with specific antibodies. The differently prepared CuO-NPs were characterized by X-ray diffraction, transmission electron microscopy and dynamic light scattering. The antibacterial activities of the unmodified CuO-NPs and the antibody-functionalized nanoparticles (CuO-NP-AbGram- and CuO-NP-AbGram+ ) were determined for both Gram-negative Escherichia coli and Gram-positive Bacillus subtilis bacteria. The antibody-functionalized NPs showed a differential increase of their antibacterial activity according to the specific antibody. The CuO-NP-AbGram- in E. coli showed reduced half maximal inhibitory concentration (IC50 ) and minimum inhibitory concentration (MIC) values when compared with unfunctionalized CuO-NPs. On the other hand, the CuO-NP-AbGram+ also showed reduced IC50 and MIC values in B. subtilis, when compared with non-functionalized CuO-NPs. Thus, the functionalized CuO nanoparticles with specific antibodies showed enhanced specificity of their antibacterial activity. The advantages of "smart" antibiotic nanoparticles are discussed.


Assuntos
Cobre , Nanopartículas , Escherichia coli , Anticorpos , Antibacterianos/farmacologia , Óxidos
9.
Sports (Basel) ; 11(8)2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37624130

RESUMO

BACKGROUND: Plyometric jump training (PJT) encompasses a range of different exercises that may offer advantages over other training methods to improve human physical capabilities (HPC). However, no systematic scoping review has analyzed either the role of the type of PJT exercise as an independent prescription variable or the gaps in the literature regarding PJT exercises to maximize HPC. OBJECTIVE: This systematic scoping review aims to summarize the published scientific literature and its gaps related to HPC adaptations (e.g., jumping) to PJT, focusing on the role of the type of PJT exercise as an independent prescription variable. METHODS: Computerized literature searches were conducted in the PubMed, Web of Science, and SCOPUS electronic databases. Design (PICOS) framework: (P) Healthy participants of any age, sex, fitness level, or sports background; (I) Chronic interventions exclusively using any form of PJT exercise type (e.g., vertical, unilateral). Multimodal interventions (e.g., PJT + heavy load resistance training) will be considered only if studies included two experimental groups under the same multimodal intervention, with the only difference between groups being the type of PJT exercise. (C) Comparators include PJT exercises with different modes (e.g., vertical vs. horizontal; vertical vs. horizontal combined with vertical); (O) Considered outcomes (but not limited to): physiological, biomechanical, biochemical, psychological, performance-related outcomes/adaptations, or data on injury risk (from prevention-focused studies); (S) Single- or multi-arm, randomized (parallel, crossover, cluster, other) or non-randomized. RESULTS: Through database searching, 10,546 records were initially identified, and 69 studies (154 study groups) were included in the qualitative synthesis. The DJ (counter, bounce, weighted, and modified) was the most studied type of jump, included in 43 study groups, followed by the CMJ (standard CMJ or modified) in 19 study groups, and the SJ (standard SJ or modified) in 17 study groups. Strength and vertical jump were the most analyzed HPC outcomes in 38 and 54 studies, respectively. The effects of vertical PJT versus horizontal PJT on different HPC were compared in 21 studies. The effects of bounce DJ versus counter DJ (or DJ from different box heights) on different HPC were compared in 26 studies. CONCLUSIONS: Although 69 studies analyzed the effects of PJT exercise type on different HPC, several gaps were identified in the literature. Indeed, the potential effect of the PJT exercise type on a considerable number of HPC outcomes (e.g., aerobic capacity, flexibility, asymmetries) are virtually unexplored. Future studies are needed, including greater number of participants, particularly in groups of females, senior athletes, and youths according to maturity. Moreover, long-term (e.g., >12 weeks) PJT interventions are needed.

10.
Pharmaceutics ; 13(11)2021 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-34834379

RESUMO

Asparaginase (ASNase) is a widely applied chemotherapeutic drug that is used to treat Acute Lymphoblastic Leukemia (ALL); however, immune responses and silent inactivation of the drug often limit its bioavailability. Many strategies have been proposed to overcome these drawbacks, including the development of improved formulations (biobetters), but only two of them are currently on the market. Nano- and micro-encapsulation are some of the most promising and novel approaches to enhance in vivo performance of ASNase, preventing the direct contact of the enzyme with the environment, protecting it from protease degradation, increasing the enzymes catalytic half-life, and in some cases, reducing immunogenicity. This review summarizes the strategies, particularly for ASNase nano- and micro-encapsulation, and their main findings, constraints, and current gaps in the state-of-the-art knowledge. The pros and cons of the use of different nanocarriers are discussed with the idea to ultimately provide safer and more effective treatments for patients with ALL.

11.
Pharmaceutics ; 13(5)2021 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-33922106

RESUMO

Asparaginase (ASNase) is a biopharmaceutical for Acute Lymphoblastic Leukemia (ALL) treatment. However, it shows undesirable side effects such as short lifetimes, susceptibility to proteases, and immunogenicity. Here, ASNase encapsidation was genetically directed in bacteriophage P22-based virus-like particles (VLPs) (ASNase-P22 nanoreactors) as a strategy to overcome these challenges. ASNase-P22 was composed of 58.4 ± 7.9% of coat protein and 41.6 ± 8.1% of tetrameric ASNase. Km and Kcat values of ASNase-P22 were 15- and 2-fold higher than those obtained for the free enzyme, respectively. Resulting Kcat/Km value was 2.19 × 105 M-1 s-1. ASNase-P22 showed an aggregation of 60% of the volume sample when incubated at 37 °C for 12 days. In comparison, commercial asparaginase was completely aggregated under the same conditions. ASNase-P22 was stable for up to 24 h at 37 °C, independent of the presence of human blood serum (HBS) or whether ASNase-P22 nanoreactors were uncoated or PEGylated. Finally, we found that ASNase-P22 caused cytotoxicity in the leukemic cell line MOLT-4 in a concentration dependent manner. To our knowledge, this is the first work where ASNase is encapsulated inside of VLPs, as a promising alternative to fight ALL.

13.
Artigo em Espanhol | LILACS | ID: biblio-1003812

RESUMO

RESUMEN: La odontología está en búsqueda de miradas más integradoras, una de ellas se relaciona con la sexualidad. La educación sexual en odontología, ha tenido escasa representación curricular, instalándose más desde lo curativo que de lo preventivo. Este estudio evaluó el grado de conocimiento, las conductas y motivos relativos a los métodos preventivos y al riesgo asociado a las prácticas de sexo oral, en estudiantes de odontología de una universidad chilena. Material y métodos: Este estudio cuantitativo, transversal y analítico, utilizó como instrumento de recogida de datos, una encuesta anónima y autoaplicada, en 50 estudiantes voluntarios. Este instrumento indagó acerca de las condiciones relativas a salud sexual, específicamente en prácticas de sexo oral. Los análisis estadísticos fueron realizados utilizando los programas SPSS® v20 y Excel®. Resultados: En cuanto a los conocimientos de métodos preventivos para prácticas de sexo oral, además del condón, otras barreras fueron poco conocidas (13%). El 90% reportó haber practicado sexo oral alguna vez, de estos, 78% no utilizó barreras de protección. De los que reportaron haber usado barrera, el 100% utilizó condón. Conclusiones: Los conocimientos, conductas y motivos en salud sexual denotan un conocimiento deficiente relativo a métodos preventivos para prácticas de sexo oral y su riesgo asociado.


ABSTRACT: Dentistry is in search of more inclusive points of view, one of them related to sexuality. Sexual education has had little curricular representation in Dentistry, being approached more from a curative point of view rather than a preventive one. This study evaluated the degree of knowledge, conduct and motives related to preventive methods and the risk associated with oral sex practices among dental students of a Chilean university. Materials and methods: This quantitative, transversal and analytical study used an anonymous and self-applied survey on 50 voluntary students. The instrument inquired about conditions related to sexual health, specifically oral sex practices. Statistical data was analyzed using softwares such as SPSS v20 and Excel. Results: In terms of knowledge about preventive methods for oral sex practices, aside from condoms, other barriers where little known (13%); 90% reported having practiced oral sex once, and among these, 78% didn't use protection barriers. Of those who reported having used a barrier, 100% used condoms. Conclusions: Knowledge, conducts and motives in sexual health report a deficient knowledge of preventive methods for oral sex practices and their associated risk.


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Comportamento Sexual , Estudantes de Odontologia , Risco , Sexualidade , Saúde Sexual
14.
Am J Clin Oncol ; 30(1): 1-7, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17278887

RESUMO

OBJECTIVES: Differences in the clinical characteristics of ovarian tumors of low malignant potential (LMP) and ovarian cancer have suggested divergences in tumor biology. The aim of this population-based study was to compare the risk of a second primary breast cancer after a history of either an LMP tumor or an epithelial ovarian cancer. METHODS: Breast cancers were evaluated among 3297 women with a history of LMP tumors, and 45,986 women with a history of epithelial ovarian cancer, within the Surveillance, Epidemiology, and End Results (SEER) Program. The expected incidence of breast cancer was then determined as a function of year, age, race, and geographic location, and combined with the observed incidence to derive the standardized incidence ratio (SIR). RESULTS: Forty-one (1.2%) patients with an LMP history were diagnosed with breast cancer, where 56.8 cases were expected, for an SIR of 0.72 [95% confidence interval (CI) 0.52-0.98]. Similarly, 734 patients (1.6%) with a history of ovarian cancer were diagnosed with breast cancer, where 809 were expected, for an SIR of 0.91 (95% CI 0.84-0.98). Overall, LMP patients were younger and had a shorter time between diagnoses. LMP patients also had a significantly lower relative risk of developing second primary breast cancers. CONCLUSION: Patients with a history of having either an LMP tumor or an epithelial ovarian cancer have a less than expected risk of subsequent breast cancer. Patients with LMP tumors are at lower risk than patients with a history of ovarian cancer for the development of these second malignancies.


Assuntos
Neoplasias da Mama/epidemiologia , Segunda Neoplasia Primária/epidemiologia , Neoplasias Ovarianas/patologia , Adenocarcinoma/epidemiologia , Adenocarcinoma/mortalidade , Neoplasias da Mama/mortalidade , Cistadenocarcinoma/epidemiologia , Cistadenocarcinoma/mortalidade , Feminino , Humanos , Incidência , Segunda Neoplasia Primária/mortalidade , Neoplasias Ovarianas/epidemiologia , Neoplasias Ovarianas/mortalidade , Análise de Sobrevida , Estados Unidos/epidemiologia
16.
Asunción; EDIFAO; 1987. 15 p. ilus, graf.
Monografia em Espanhol | LILACS, BDNPAR | ID: lil-321044
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