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1.
Sci Total Environ ; 904: 166982, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37741378

RESUMO

Biodiesel is considered as one of the most promising alternative fuels due to the depletion of fossil fuels and the need to cope with potential energy shortages in the future. This article provides a thorough analysis of biodiesel synthesis, covering a variety of topics including oil feedstock, synthesis methods, catalysts, and enhancement technologies. Different oil feedstock for the synthesis of biodiesel is compared in the review, including edible plant oil, non-edible plant oil, waste cooking oil, animal fat, microbial oil, and algae oil. In addition, different methods for the synthesis of biodiesel are discussed, including direct use, blending, thermal cracking, microemulsions, and transesterification processes, highlighting their respective advantages and disadvantages. Among them, the transesterification method is the most commonly used and a thorough examination is given of the benefits and drawbacks of utilizing enzymatic, heterogeneous, and homogeneous catalysts in this process. Moreover, this article provides an overview of emerging intensification technologies, such as ultrasonic and microwave-assisted, electrolysis, reactive distillation, and microreactors. The benefits and limitations of these emerging technologies are also reviewed. The contribution of this article is offering a thorough and detailed review of biodiesel production technologies, focusing mainly on recent advances in enhanced chemical reaction processes. This provides a resource for researchers to assess and compare the latest advancements in their investigations. It also opens up the potential for enhancing the value of oil feedstocks efficiently, contributing to the development of new energy sources.


Assuntos
Biocombustíveis , Melhoramento Biomédico , Animais , Óleos de Plantas , Esterificação , Alimentos
2.
Psicol. ciênc. prof ; 43: e252743, 2023.
Artigo em Português | LILACS, Index Psicologia - Periódicos | ID: biblio-1448951

RESUMO

O objetivo desta pesquisa é identificar e compreender fenomenologicamente, por meio de relato de Psicólogos de Esporte (PE) e de Coaches, em sua vivência prática, como ocorrem os processos reflexivos em sua atuação, conforme apreendidos a partir de relatos de experiências. O método de investigação escolhido foi a fenomenologia, pois oferece os recursos necessários para tal mergulho junto à experiência reflexiva. A amostra intencional foi delineada por PE e Coaches (profissionais de Educação Física que recorrem ao Coaching) em atividade em esportes de alto rendimento, que tenham atuado ou estejam atuando em modalidades esportivas coletivas e/ou individuais. Realizaram-se nove entrevistas (cinco com PE, quatro com Coaches). O acesso ao objeto desse estudo se deu por meio de entrevistas em profundidade e semiestruturadas, orientadas pela escuta suspensiva. As questões disparadoras foram formuladas com base no Procedimento Estruturado de Reflexão adaptado. Para análise das entrevistas, realizou-se uma síntese de cada relato, seguindo-se de cruzamento intencional. Como resultados, percebeu-se que PE e Coaches trazem algumas similaridades no que se refere aos modos de refletir sobre sua prática. No entanto, as experiências que eles fazem desses processos reflexivos é que podem tomar rumos distintos. Os(as) PE amparam-se na regulamentação da profissão e resguardam-se em seus apontamentos, trazendo suas experiências e reflexões sobre os processos vividos. Os(as) Coaches trazem em suas explanações um trabalho coerente, organizado e compatível com o método do Coaching. Problematizar os processos reflexivos desses profissionais permite diferenciar qualitativa e eticamente suas atuações, possibilitando o fomento multiprofissional no esporte.(AU)


The aim of this study consists in phenomenologically identifying and understanding, by the report of Sport Psychologists (SP) and coaches, in their practical experience, how would be the reflexive processes that take place in their performance, as learned from reports of their experiences. The research method chosen was phenomenology, since it offers the necessary resources for such a dive along with the reflective experience. The intentional sample was outlined by SP and coaches (Physical Education professionals who use coaching) active in high performance sports, who have or are working in collective and/or individual sports. Nine interviews were conducted (five with SP, four with coaches). Access to the object of this study took place by in-depth and semi-structured interviews, guided by suspensive listening. The triggering questions were formulated based on the adapted Structured Reflection Procedure. For the analysis of the interviews, a synthesis of each report was carried out, followed by the intentional crossing. As results, it was noticed that SP and coaches bring some similarities regarding the ways of reflecting on their practice. However, their experiences of these reflective processes are that they can take different directions. The SP are based on the regulation of the profession and guard themselves in their notes, bringing their experiences and reflections on the processes experienced. Coaches bring in their explanations a coherent, organized, and compatible work with the coaching method. Problematizing the reflective processes of these professionals allows to differentiate their actuation qualitatively and ethically, making the multiprofessional phenomenon in sport possible.(AU)


El objetivo de este estudio consiste en identificar y comprender fenomenológicamente, a partir de la experiencia práctica de psicólogos del deporte (PD) y coaches, cómo serían los procesos reflexivos que se llevan a cabo en su rendimiento, tal y como se desprende de los informes de experiencias. El método de investigación elegido fue la fenomenología, ya que ofrece los recursos necesarios junto con la experiencia. La muestra intencional fue delineada por PD y coaches (profesionales de la educación física que utilizan el coaching) activos en deportes de alto rendimiento, que tienen o están trabajando en deportes colectivos e/o individuales. Se realizaron nueve entrevistas (cinco con PD, cuatro con coaches). El acceso al objeto de este estudio fue entrevistas en profundidad y semiestructuradas, guiadas por escuchas suspensivas. Las preguntas se formularon desde el procedimiento de reflexión estructurado adaptado. Para el análisis de las entrevistas, se hizo una síntesis de cada informe, seguida del cruce intencional. Como resultados, se notó que los PD y coaches tienen algunas similitudes con respecto a las formas de reflexionar sobre su práctica. Sin embargo, las experiencias que hacen de estos procesos pueden tomar diferentes direcciones. Los(las) PD se basan en la regulación de la profesión y se protegen en sus notas, aportando sus experiencias y reflexiones sobre los procesos vividos. Los(las) coaches plantean en sus explicaciones un trabajo coherente, organizado y compatible con el método de Coaching. Problematizar los procesos reflexivos de estos profesionales permite diferenciar sus acciones de manera cualitativa y ética, además de posibilitar la promoción multiprofesional en el deporte.(AU)


Assuntos
Humanos , Masculino , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Psicologia do Esporte , Tutoria , Ansiedade , Avaliação de Processos e Resultados em Cuidados de Saúde , Satisfação Pessoal , Aptidão , Educação Física e Treinamento , Resistência Física , Disciplinas das Ciências Naturais , Jogos e Brinquedos , Competência Profissional , Psicologia , Desempenho Psicomotor , Qualidade da Assistência à Saúde , Qualidade de Vida , Recreação , Reabilitação , Corrida , Atenção , Ciência , Sono , Futebol , Controle Social Formal , Identificação Social , Justiça Social , Medicina Esportiva , Estresse Psicológico , Natação , Ensino , Terapêutica , Atletismo , Orientação Vocacional , Ferimentos e Lesões , Yoga , Ciências do Comportamento , Exercícios Respiratórios , Saúde , Saúde Mental , Aptidão Física , Inquéritos e Questionários , Reprodutibilidade dos Testes , Saúde Ocupacional , Caminhada , Autonomia Profissional , Guias como Assunto , Entrevista , Congressos como Assunto , Meditação , Vida , Disciplinas e Atividades Comportamentais , Senso de Humor e Humor , Academias de Ginástica , Gerenciamento da Prática Profissional , Síndromes da Dor Regional Complexa , Credenciamento , Intervenção em Crise , Terapias Mente-Corpo , Técnicas de Exercício e de Movimento , Melhoramento Biomédico , Depressão , Dieta , Dietética , Educação não Profissionalizante , Avaliação de Desempenho Profissional , Emprego , Ética Profissional , Fiscalização Sanitária , Capacitação Profissional , Desempenho Atlético , Treinamento Resistido , Resiliência Psicológica , Fenômenos Fisiológicos Musculoesqueléticos e Neurais , Comportamento Alimentar , Atletas , Fortalecimento Institucional , Ciências da Nutrição e do Esporte , Volta ao Esporte , Desempenho Profissional , Profissionalismo , Aptidão Cardiorrespiratória , Sucesso Acadêmico , Esportes Aquáticos , Engajamento no Trabalho , Psicologia Cognitiva , Ciência e Desenvolvimento , Treino Cognitivo , Bem-Estar Psicológico , Condições de Trabalho , Ginástica , Ocupações em Saúde , Promoção da Saúde , Anatomia , Descrição de Cargo , Jurisprudência , Liderança , Aprendizagem , Estilo de Vida , Memória , Métodos , Motivação , Atividade Motora , Destreza Motora , Movimento , Relaxamento Muscular , Músculos , Obesidade
4.
J Gastroenterol Hepatol ; 37(10): 1955-1962, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35945162

RESUMO

BACKGROUND AND AIM: The management of bleeding during endoscopic submucosal dissection (ESD) is critical and related to the procedure time. We collaborated on a new image enhancement algorithm with parameter optimization for clinical use being developed by FUJIFILM Co. and processed white light image data offline to evaluate the effectiveness of this technology. This study aims to evaluate the clinical usefulness of this technology. METHODS: Eighteen video scenes of bleeding points from five gastric ESDs were selected and processed by the new image enhancement algorithm. The time until a bleeding point was found, visibility of a bleeding point, and color abnormality of the submucosal layer were evaluated by ESD experts, ESD trainees, and endoscopy trainees. The color differences between the bleeding point and the surroundings in CIE-L*a*b* color space were calculated in the original and enhanced images. RESULTS: The time until a bleeding point was found in the enhanced videos was significantly shorter than that in the original videos (11.10 s vs 13.85 s) (P = 0.017). On a 5-point (-2 to +2) Likert scale of visibility, the enhanced image was slightly superior to the original (+0.45), and the appearance of the submucosa was comparable between images (+0.14). The color difference among the bleeding areas on the enhanced images was significantly larger than that on the original images (10.93 vs 8.36). CONCLUSION: This novel image enhancement algorithm emphasizes the color difference between a bleeding point and the surrounding area, which would help find bleeding points faster during ESD for the less experienced endoscopists.


Assuntos
Melhoramento Biomédico , Ressecção Endoscópica de Mucosa , Neoplasias Gástricas , Ressecção Endoscópica de Mucosa/efeitos adversos , Ressecção Endoscópica de Mucosa/métodos , Endoscopia Gastrointestinal , Mucosa Gástrica/diagnóstico por imagem , Mucosa Gástrica/cirurgia , Hemorragia , Humanos , Aumento da Imagem , Neoplasias Gástricas/diagnóstico por imagem , Neoplasias Gástricas/cirurgia , Tecnologia , Resultado do Tratamento
5.
Front Immunol ; 13: 931052, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35898510

RESUMO

Salmonella enterica is a leading cause of food-borne diseases in humans worldwide, resulting in severe morbidity and mortality. They are carried asymptomatically in the intestine or gallbladder of livestock, and are transmitted predominantly from animals to humans via the fecal-oral route. Thus, the best preventive strategy is to preemptively prevent transmission to humans by vaccinating livestock. Live attenuated vaccines have been mostly favored because they elicit both cellular and humoral immunity and provide long-term protective immunity. However, developing these vaccines is a laborious and time-consuming process. Therefore, most live attenuated vaccines have been mainly used for phenotypic screening using the auxotrophic replica plate method, and new types of vaccines have not been sufficiently explored. In this study, we used Radiation-Mutation Enhancement Technology (R-MET) to introduce a wide variety of mutations and attenuate the virulence of Salmonella spp. to develop live vaccine strains. The Salmonella Typhimurium, ST454 strain (ST WT) was irradiated with Cobalt60 gamma-irradiator at 1.5 kGy for 1 h to maximize the mutation rate, and attenuated daughter colonies were screened using in vitro macrophage replication capacity and in vivo mouse infection assays. Among 30 candidates, ATOMSal-L6, with 9,961-fold lower virulence than the parent strain (ST454) in the mouse LD50 model, was chosen. This vaccine candidate was mutated at 71 sites, and in particular, lost one bacteriophage. As a vaccine, ATOMSal-L6 induced a Salmonella-specific IgG response to provide effective protective immunity upon intramuscular vaccination of mice. Furthermore, when mice and sows were orally immunized with ATOMSal-L6, we found a strong protective immune response, including multifunctional cellular immunity. These results indicate that ATOMSal-L6 is the first live vaccine candidate to be developed using R-MET, to the best of our knowledge. R-MET can be used as a fast and effective live vaccine development technology that can be used to develop vaccine strains against emerging or serotype-shifting pathogens.


Assuntos
Melhoramento Biomédico , Vacinas contra Salmonella , Animais , Anticorpos Antibacterianos/genética , Feminino , Humanos , Imunoglobulina G/genética , Camundongos , Mutação , Vacinas contra Salmonella/genética , Salmonella typhimurium , Suínos , Vacinas Atenuadas
6.
Contrast Media Mol Imaging ; 2022: 7762622, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35685659

RESUMO

The application of endoscopic imaging in the biopsy of malignant laryngeal lesions is one of the current research hotspots in the medical field. Based on the narrowband imaging resolution enhancement technology, a model for postoperative examination of laryngeal malignant tumor was constructed in this paper. The article calculated the biopsy detection rate of malignant lesions and the correct biopsy detection rate of the two groups and made a statistical comparison. In the NBI mode group, the mucosal morphology and superficial mucosal microvascular morphology of the same lesion under two different modes of white light and NBI were compared, which solved the problem of data processing of cases. During the case comparison process, patients who needed biopsies to be sent for pathology were selected for inclusion in the study and were randomly divided into two groups. The coincidence rate of EUS combined with NBI diagnosis was significantly higher than that of ordinary white light gastroscopy (47.92%), and the difference was statistically significant (P=0.000 < 0.05). The experimental results compared the accuracy of the normal white light mode and the NBI mode to diagnose the nature of the lesions: according to the Kudo classification criteria, 23 cases of tumor lesions were to be diagnosed in the normal white light mode, with an accuracy rate of 69.70%, and the NBI mode was to be used to diagnose tumors. There were 81 cases of sexual lesions, with an accuracy rate of 93.94%. The NBI mode was more accurate in diagnosing the nature of the lesions under the Kudo classification standard (P < 0.05). In 64 cases, the accuracy rate was 63.63%. Under the NBI mode, 29 cases of tumor lesions were proposed to be diagnosed, and the accuracy rate was 87.88% to promote the application of NBI endoscopy in the biopsy of malignant laryngeal lesions.


Assuntos
Melhoramento Biomédico , Neoplasias Laríngeas , Humanos , Neoplasias Laríngeas/diagnóstico por imagem , Neoplasias Laríngeas/cirurgia , Luz , Imagem de Banda Estreita , Sensibilidade e Especificidade
7.
Eur Arch Otorhinolaryngol ; 279(1): 293-298, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34487219

RESUMO

PURPOSE: Flexible endoscopic evaluation of swallowing (FEES®) is a standard diagnostic tool in dysphagia. The combination of FEES® and narrow band light (narrow band imaging; NBI) provides a more precise and detailed investigation method. So far, this technique could only be performed with the NBI illumination. The new version of the "professional image enhancement technique" (PIET) provides another image enhancing system. This study investigates the eligibility of PIET in the FEES® procedure. METHODS: Both techniques, NBI and PIET, were compared using a target system. Furthermore, the image enhancement during FEES® was performed and recorded with the two systems during daily routine. RESULTS: Performing an image enhancement during FEES® is possible with both systems PIET and NBI. On the target system, the contrast of the PIET showed a brighter and a more detailed picture. In dysphagia patients, no difference between PIET and NBI was detected. CONCLUSIONS: PIET proved to be non-inferior to NBI during image enhancement FEES®. So far, image enhancement FEES® was exclusively connected to NBI. With the PIET system, an alternative endoscopy technology is available for certain indications.


Assuntos
Melhoramento Biomédico , Aumento da Imagem , Endoscópios , Endoscopia Gastrointestinal , Humanos , Imagem de Banda Estreita
8.
Int J Pharm ; 610: 121258, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34740760

RESUMO

Physical drug delivery enhancement in skin has been shown to enhance cosmeceutical actives efficacy. Among the physical drug delivery enhancement technologies, microneedle is the most commercially successful technology. However, there are pros and cons like other physical enhancement technologies including variabilities in penetration depth and lack of efficacy. In this study, three physical topical dug delivery enhancements, elongated microparticles, microneedles and dermaroller, were applied to ex vivo pig skin and compared. The model topical drug that was used is 5-Aminolevulinic acid, the most commonly used photosensitiser prodrug. The skin was pre-treated before mounting on to Franz cell diffusion apparatus. Transdermal epidermal water loss was measured, and receptor fluids were collected at 7 time points for HPLC analysis. The results show that all three technologies disrupted the skin surface. All microporation pre-treatments significantly enhanced mALA cumulative permeation over 8 h (p < 0.001), with the 24x dermaroller significantly greater than 12x dermaroller (p < 0.001) and both dermaroller treatments significantly greater than microneedles and elongated microparticles (p < 0.05). The microporation pre-treatments all significantly increased mALA deposition in the stratum corneum and deeper skin tissues compared to passive administration, with deposition increases ranging from 3.6x to 15.1x that of passive administration. The DR pretreatment showed highest enhancement ratios (amount 5-Aminolevulinic acid in skin at 8 h following pretreatment v passive) with the following order of enhancement: 24x dermaroller > 12x dermaroller > microneedles > elongated microparticles. In conclusion, physical enhancement tools such as microneedles, dermarollers and elongated microparticles demonstrated significant penetration and retention of mALA through/into piglet skin. Further study is needed to determine the cost, dose and patient compliance.


Assuntos
Ácido Aminolevulínico , Melhoramento Biomédico , Administração Cutânea , Animais , Pele/metabolismo , Absorção Cutânea , Suínos
9.
ACS Appl Mater Interfaces ; 13(33): 39112-39125, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34384220

RESUMO

Autophagy inhibition could hinder the underlying protective mechanisms in the course of tumor treatment. The advances in autophagy inhibition have driven focus on the functionalized nanoplatforms by combining the current treatment paradigms with complementary autophagy inhibition for enhanced efficacy. Furthermore, Ca2+ overload is also a promising adjuvant target for the tumor treatment by augmenting mitochondrial damage. In this view, complementary mitochondrial Ca2+ overload and autophagy inhibition were first demonstrated as a novel strategy suitable for homing in on the shortage of photodynamic therapy (PDT). We constructed biodegradable tumor-targeted inorganic/organic hybrid nanocomposites (DPGC/OI) synchronously encapsulating IR780 and Obatoclax by biomineralization of the nanofilm method, which consists of pH-triggered calcium phosphate (CP), long circulation phospholipid block copolymers 1,2-distearoyl-sn-glycero-3-phosphoethanolamine (DSPE)-poly(ethylene glycol) (PEG)2000-glucose (DPG). In the presence of the hydrophilic PEG chain and glucose transporter 1 (Glut-1) ligands, DPGC would become an effectively tumor-oriented nanoplatform. Subsequently, IR780 as an outstanding photosensitizer could produce increased amounts of toxic reactive oxygen species (ROS) after laser irradiation. Calcium phosphate (CP) as the Ca2+ nanogenerator could generate Ca2+ at low pH to induce mitochondrial Ca2+ overload. The dysfunction of mitochondria could enhance increased amounts of ROS. Based on the premise that autophagy would degrade dysfunctional organelles to sustain metabolism and homeostasis, which might participate in resistance to PDT, Obatoclax as an autophagy inhibitor would hinder the protective mechanism from cancer cells with negligible toxicity. Such an enhanced PDT via mitochondrial Ca2+ overload and autophagy inhibition could be realized by DPGC/OI.


Assuntos
Autofagia/efeitos dos fármacos , Fosfatos de Cálcio/química , Glucose/química , Indóis/química , Nanocompostos/química , Fosfatidiletanolaminas/química , Fármacos Fotossensibilizantes/química , Polietilenoglicóis/química , Animais , Transporte Biológico , Melhoramento Biomédico , Feminino , Humanos , Indóis/metabolismo , Indóis/farmacologia , Camundongos Endogâmicos BALB C , Mitocôndrias/metabolismo , Mitocôndrias/ultraestrutura , Neoplasias/diagnóstico por imagem , Neoplasias/terapia , Fosfolipídeos/química , Fotoquimioterapia , Fármacos Fotossensibilizantes/farmacologia , Pirróis/química , Pirróis/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Propriedades de Superfície , Distribuição Tecidual
10.
Rev. bioét. (Impr.) ; 29(1): 87-99, enero-mar. 2021.
Artigo em Português | LILACS | ID: biblio-1251075

RESUMO

Resumo Funções cognitivas são alvo frequente de curiosidade, estudo e reflexão, pois são estruturantes para o ser o humano tal como o conhecemos. Compreender os limites cognitivos, os processos que os originam e a forma de os ultrapassar é, por isso, forma de entender a condição humana e de perceber as consequências da potencial manipulação da cognição. Nos últimos anos tem havido interesse crescente no melhoramento cognitivo mediante o uso de fármacos, e com ele têm surgido diversos e importantes dilemas éticos, médicos e legais. O objetivo deste ensaio é refletir sobre os problemas éticos levantados. Pode-se concluir que o melhoramento cognitivo farmacológico tem de ser mais bem estudado no nível farmacodinâmico para que sua aplicação - regulada e em contextos específicos - possa beneficiar indivíduos e sociedade, não pondo em causa a autenticidade da condição humana.


Abstract Human cognitive functions are often targets of curiosity, study and reflections, since they are essential for human beings. Understanding our cognitive boundaries, the processes that originate them, and how to overcome them means comprehending the human condition and the consequences of manipulating cognition. In recent years, growing interest has been observed in cognitive enhancement with the help of drugs, resulting in several important ethical, medical, and legal dilemmas. This article analyzed the ethical issues involved in this process and concluded that pharmacological cognitive enhancement needs further studies at the pharmacodynamic level, so that its application - regulated and in specific contexts - can benefit individuals and society, without undermining the authenticity of the human condition.


Resumen Las funciones cognitivas humanas son objeto frecuente de curiosidad, estudio y reflexión, ya que estructuran el ser humano tal como lo conocemos. Comprender los límites cognitivos, los procesos que los originan y la forma de superarlos es, por lo tanto, una forma de entender la condición humana y percibir las consecuencias de la potencial manipulación de la cognición. En los últimos años ha habido un interés creciente en el mejoramiento cognitivo a través del uso de productos farmacéuticos, y con ello han surgido una serie de importantes dilemas éticos, médicos y legales. El propósito de este ensayo es reflexionar sobre los problemas éticos planteados. Se puede concluir que el mejoramiento cognitivo farmacológico debe estudiarse mejor en el ámbito farmacodinámico, de modo que su aplicación, regulada y en contextos específicos, pueda beneficiar a individuos y a la sociedad sin comprometer la autenticidad de la condición humana.


Assuntos
Nootrópicos , Melhoramento Biomédico , Ética Médica
11.
J Phys Chem Lett ; 12(7): 1786-1792, 2021 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-33576633

RESUMO

The structures of many membrane-bound proteins and polypeptides depend on the membrane potential. However, spectroscopically studying their structures under an applied field is challenging, because a potential is difficult to generate across more than a few bilayers. We study the voltage-dependent structures of the membrane-bound polypeptide, alamethicin, using a spectroelectrochemical cell coated with a rough, gold film to create surface plasmons. The plasmons sufficiently enhance the 2D IR signal to measure a single bilayer. The film is also thick enough to conduct current and thereby apply a potential. The 2D IR spectra resolve features from both 310- and α-helical structures and cross-peaks connecting the two. We observe changes in the peak intensity, not their frequencies, upon applying a voltage. A similar change occurs with pH, which is known to alter the angle of alamethicin relative to the surface normal. The spectra are modeled using a vibrational exciton Hamiltonian, and the voltage-dependent spectra are consistent with a change in angle of the 310- and α-helices in the membrane from 55 to 44°and from 31 to 60°, respectively. The 310- and α-helices are coupled by approximately 10 cm-1. These experiments provide new structural information about alamethicin under a potential difference and demonstrate a technique that might be applied to voltage-gated membrane proteins and compared to molecular dynamics structures.


Assuntos
Alameticina/química , Melhoramento Biomédico/métodos , Proteínas de Membrana/química , Sequência de Aminoácidos , Bicamadas Lipídicas/química , Potenciais da Membrana , Simulação de Dinâmica Molecular , Conformação Proteica , Espectrofotometria Infravermelho , Propriedades de Superfície , Vibração
12.
Adv Mater ; 33(7): e2006057, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33448062

RESUMO

Short-wave infrared (SWIR, 900-1700 nm) enables in vivo imaging with high spatiotemporal resolution and penetration depth due to the reduced tissue autofluorescence and decreased photon scattering at long wavelengths. Although small organic SWIR dye molecules have excellent biocompatibility, they have been rarely exploited as compared to their inorganic counterparts, mainly due to their low quantum yield. To increase their brightness, in this work, the SWIR dye molecules are placed in close proximity to gold nanorods (AuNRs) for surface plasmon-enhanced emission. The fluorescence enhancement is optimized by controlling the dye-to-AuNR number ratio and up to ≈45-fold enhancement factor is achieved. In addition, the results indicate that the highest dye-to-AuNR number ratio gives the highest emission intensity per weight and this is used for synthesizing SWIR imaging probes using layer-by-layer (LbL) technique with polymer coating protection. Then, the SWIR imaging probes are applied for in vivo imaging of ovarian cancer and the surface coating effect on intratumor distribution of the imaging probes is investigated in two orthotopic ovarian cancer models. Lastly, it is demonstrated that the plasmon-enhanced SWIR imaging probe has great potential for fluorescence imaging-guided surgery by showing its capability to detect sub-millimeter-sized tumors.


Assuntos
Materiais Biocompatíveis/química , Corantes Fluorescentes/química , Ouro/química , Nanotubos/química , Imagem Óptica/métodos , Neoplasias Ovarianas/diagnóstico por imagem , Animais , Melhoramento Biomédico , Linhagem Celular Tumoral , Feminino , Humanos , Raios Infravermelhos , Luciferases/química , Luciferases/genética , Camundongos Nus , Polímeros/química , Ondas de Rádio , Propriedades de Superfície , Distribuição Tecidual
13.
J Photochem Photobiol B ; 214: 112091, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33285487

RESUMO

Formaldehyde (FA), a simple reactive carbonyl molecule, is endogenously produced in the cell at various physiological condition. At elevated level, FA causes severe cell toxicity as well as damage in macromolecules such proteins and DNA. For detecting FA in living cell, we identify a small but effective fluorescent turn on probe comprising single benzene-based orothophenylenediamine compound. Further study reveals that carboxylic group in orothophenylenediamine plays the important role in enhancing fluorescent signal than another electron withdrawing group. It is even interesting to observe the occurrence of fluorescent enhancement in glutathione (GSH) environment which is generally abundant in every cell. Our probe enables to detect FA over other bio-analytes efficiently with limit of detection of 123 nM and 355-fold of enhancement in cellular mimicking conditions. Moreover, this probe could be useful in discriminating cell that has high concentration of FA as well as GSH.


Assuntos
Aminobenzoatos/química , Corantes Fluorescentes/química , Formaldeído/análise , Glutationa/química , Melhoramento Biomédico , Técnicas Biossensoriais , Células HeLa , Células Hep G2 , Humanos , Limite de Detecção , Imagem Óptica , Espectrometria de Fluorescência
14.
Bioorg Med Chem ; 29: 115889, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33260051

RESUMO

Various radiosensitizers are being developed to increase the radiation sensitivity of hypoxic cancer cells, which show resistance to radiation. Previously, we demonstrated that an acetyl glucose-modified nitroimidazole derivative showed a high radiosensitizing effect by inhibiting glucose uptake and glycolysis. Based on this finding, we designed and synthesized novel sugar hybrid radiosensitizers, wherein acetyl glucose was introduced into gefitinib. Among them, UTX-114 had higher autophosphorylation and radiosensitizing activity than gefitinib and inhibited glucose uptake. This result supports our hypothesis that an acetyl glucose moiety improves the radiosensitizing effect of the drug, and UTX-114 can be expected to be a leading compound with a radiosensitizing effect.


Assuntos
Antineoplásicos/química , Gefitinibe/química , Glucose/química , Nitroimidazóis/química , Radiossensibilizantes/química , Antineoplásicos/farmacologia , Melhoramento Biomédico , Linhagem Celular Tumoral , Permeabilidade da Membrana Celular , Receptores ErbB/metabolismo , Gefitinibe/farmacologia , Proteínas Facilitadoras de Transporte de Glucose/metabolismo , Glicólise/efeitos dos fármacos , Humanos , Proteínas de Transporte de Monossacarídeos/metabolismo , Fosforilação , Radiossensibilizantes/farmacologia
15.
Anal Chem ; 92(17): 11553-11557, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32867496

RESUMO

Protein digestion is a key challenge in mass spectrometry (MS)-based structural proteomics. Although using hydrogen-deuterium exchange kinetics with MS (HDX-MS) to interrogate the high-order structure of proteins is now established, it can be challenging for ß-barrel proteins, which are important in cellular transport. These proteins contain a continuous chain of H-bonds that impart stability, causing difficulty in digestion for bottom-up measurements. To overcome this impediment, we tested organic solvents as denaturants during on-line pepsin digestion of soluble ß-barrel proteins. We selected green fluorescent protein (GFP), siderocalin (Scn), and retinol-binding protein 4 (RBP4) as model proteins and screened six different polar-aprotic and polar-protic solvent combinations to disrupt the H-bonds and hydrophobic interactions holding together the ß-sheets. The use of organic solvents improves digestion, generating more peptides from the rigid ß-barrel regions, without compromising the ability to predict the retinol binding site on RBP4 when adopting this proteolysis with HDX.


Assuntos
Espectrometria de Massa com Troca Hidrogênio-Deutério/métodos , Proteínas/química , Melhoramento Biomédico , Deutério/química , Proteínas de Fluorescência Verde/química , Hidrogênio/química , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Lipocalina-2/química , Pepsina A/metabolismo , Proteólise , Proteínas Celulares de Ligação ao Retinol/química , Solventes/química
16.
Chem Soc Rev ; 49(15): 5110-5139, 2020 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-32697225

RESUMO

In this tutorial review, we will explore recent advances in the construction and application of Förster resonance energy transfer (FRET)-based small-molecule fluorescent probes. The advantages of FRET-based fluorescent probes include: a large Stokes shift, ratiometric sensing and dual/multi-analyte responsive systems. We discuss the underlying energy donor-acceptor dye combinations and emphasise their applications for the detection or imaging of cations, anions, small neutral molecules, biomacromolecules, cellular microenvionments and dual/multi-analyte responsive systems.


Assuntos
Transferência Ressonante de Energia de Fluorescência/métodos , Compostos Inorgânicos/análise , Animais , Transporte Biológico , Melhoramento Biomédico , Técnicas Biossensoriais , Linhagem Celular , Microambiente Celular , Humanos , Íons/análise , Potencial da Membrana Mitocondrial , Microscopia de Fluorescência , Neoplasias/diagnóstico por imagem , Imagem Óptica , Espectrometria de Fluorescência , Propriedades de Superfície
17.
Pharm Res ; 37(6): 100, 2020 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-32436083

RESUMO

PURPOSE: We investigated the potential correlations between skin barrier integrity and hydrophilic drugs distribution in skin in the presence of different types of penetration enhancers (PEs) and their combinations. METHODS: We measured skin conductivity to evaluate skin barrier integrity before and after the topical application of different chemical PEs, physical PE, peptide PE and their combinations in vitro. We also investigated their effect on the skin distribution profiles of two hydrophilic model drugs, Fluorescein sodium (376 Da) and Fluorescein isothiocyanate-dextrans 10 (10 KDa). RESULTS: The physical PE significantly increased the skin conductivity compared to all other PEs, while the peptide PE had no effect on it. The drug deposition in different skin layers was not only dependent on PE applied but also its own molecular weight. We further found two excellent correlations: one (R2 = 0.9388) between skin barrier integrity and total skin absorption of FNa and another one(R2 = 0.9212) between skin barrier integrity and the deposition of FNa in dermis and receptor in presence of chemical or physical PEs and their combinations. CONCLUSIONS: The total skin absorption or the deposition in dermis and receptor of small hydrophilic drug in the presence of chemical and physical PEs and their combinations show a good correlation with skin barrier integrity. However, such correlations hold true neither for large hydrophilic drug nor for peptide PE. All good relationships found in this work will allow screening suitable PEs or combinations by measuring the skin conductivity induced by corresponding PEs. Graphical Abstract The total skin absorption of small hydrophilic drug shows a good correlation with skin barrier integrity in the presence of chemical and physical penetration enhancers and their combinations. However, such a correlation hold true neither for large hydrophilic drug nor for peptide penetration enhancer.


Assuntos
Melhoramento Biomédico/métodos , Portadores de Fármacos/química , Peptídeos/química , Preparações Farmacêuticas/química , Absorção Cutânea/efeitos dos fármacos , Pele/metabolismo , Administração Cutânea , Animais , Dextranos/administração & dosagem , Dextranos/química , Composição de Medicamentos/métodos , Liberação Controlada de Fármacos , Excipientes/química , Fluoresceína/administração & dosagem , Fluoresceína/química , Fluoresceína-5-Isotiocianato/administração & dosagem , Fluoresceína-5-Isotiocianato/análogos & derivados , Fluoresceína-5-Isotiocianato/química , Cobaias , Humanos , Interações Hidrofóbicas e Hidrofílicas , Técnicas In Vitro , Conformação Molecular , Estrutura Molecular , Peso Molecular , Permeabilidade , Preparações Farmacêuticas/administração & dosagem , Solubilidade , Relação Estrutura-Atividade , Distribuição Tecidual
19.
J. Phys. Educ. (Maringá) ; 31: e3102, 2020. tab
Artigo em Inglês | LILACS | ID: biblio-1098328

RESUMO

ABSTRACT The purpose of this study was to explore the meanings of supplement use among those who engage in physical activity in fitness centers. A qualitative study was carried out based on 67 questionnaires answered on the internet by practitioners of physical training. There was also an observation of the groups in the Facebook, the dynamic and other aspects such as discussions, messages, profiles and images. It was detected that physical activity practitioners care more about the quantity of substances ingested than any other factor that may lead them to suffer certain health risks. They believe that so-called "excesses" may cause diseases to the internal organs. Although the participants believe that their own consumption of supplements does not compromise their health, a biomedical authority is crucial for them to recognize whether or not they are at risk. The consumption of supplements can vary depending on what is understood to be excessive and which risks may compromise the body. There are many motivations for managing these substances. Health risks should not be analyzed solely from a biomedical perspective, but also addressed by the socio-cultural logic of the perceptions and meanings attributed by the subjects to the body and the management thereof.


RESUMO O objetivo deste estudo foi explorar os significados do uso de suplementos entre aqueles que praticam atividade física em academias de ginástica. Um estudo qualitativo foi realizado com base em 67 questionários respondidos na internet por praticantes de atividade física. Houve também uma observação dos grupos na Facebook, a dinâmica e outros aspectos como discussões, mensagens, perfis e imagens. Foi detectado que os praticantes de atividade física se importam mais com a quantidade de substâncias ingeridas do que com qualquer outro fator que possa levá-los a sofrer certos riscos à saúde. Eles acreditam que os chamados "excessos" podem causar doenças aos órgãos internos. Embora os participantes acreditem que seu próprio consumo de suplementos não compromete a saúde, a autoridade biomédica é crucial para que eles reconheçam se estão ou não em risco. O consumo de suplementos pode variar dependendo do que se entende ser excessivo e quais os riscos que podem comprometer o corpo. Existem muitas motivações para gerenciar essas substâncias. Os riscos para a saúde não devem ser analisados apenas a partir de uma perspectiva biomédica, mas também abordados pela lógica sociocultural das percepções e significados atribuídos pelos sujeitos ao corpo e ao seu gerenciamento.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Suplementos Nutricionais , Academias de Ginástica , Educação Física e Treinamento , Comportamento , Exercício Físico , Conhecimento , Internet , Risco à Saúde Humana , Melhoramento Biomédico , Dietética , Ciências da Nutrição , Anabolizantes , Atividade Motora
20.
Saúde Soc ; 29(1): e190967, 2020.
Artigo em Português | LILACS | ID: biblio-1101906

RESUMO

Resumo Nas últimas duas décadas, o envelhecimento ativo adquiriu expressão relevante enquanto paradigma de políticas públicas para fazer face aos desafios colocados pelo envelhecimento demográfico. Definido, primeiramente pela Organização Mundial da Saúde (OMS), de forma a enfatizar a responsabilidade da sociedade no seu conjunto relativamente à qualidade de vida ao longo do processo de envelhecimento, o paradigma do envelhecimento ativo, atualmente, tem vindo a concentrar-se, sobretudo, no adiamento da idade da reforma e na redução dos custos com a saúde nos últimos anos de vida, a partir de uma lógica de responsabilização individual. Para a elaboração deste artigo, foram consultados vários sítios on-line de clínicas médicas portuguesas nas quais se praticam consultas/tratamentos de medicina antienvelhecimento, analisando os anúncios publicitários dos serviços prestados, bem como artigos de opinião redigidos pelos próprios médicos dessa especialidade, dirigidos a um público leigo. Conclui-se que, a par da responsabilização individual pela saúde e, de forma mais geral, pela forma como se envelhece, assistimos hoje à expansão de um amplo mercado de produtos e serviços antienvelhecimento que nos permitem argumentar que o ideal de envelhecimento ativo poderá estar ao serviço de uma indústria da perfeição.


Abstract In the last two decades, Active Ageing acquired significant importance in scientific and political forums as a new paradigm of public policies to meet challenges posed by the ageing population. Defined by the WHO as to emphasize society's responsibility regarding quality of life as people age, the Active Ageing paradigm represents, nowadays, a progressive narrowing of action scope and accountability. In recent years, assuming the logic of individual accountability, it serves as basis for the accusation of individual negligence in not adopting a healthy lifestyle. This study analyses the websites of several Portuguese medical clinics specialized in anti-ageing medicine, where one can find advertisements of the services provided, and, in some cases, opinion articles drawn up by doctors of this medical specialty, for a lay audience. Considering the increasing international dimension of the aesthetic and hormonal enhancement biotechnologies market, the ideal of Active ageing can, today, be at the service of the culture of perfection.


Assuntos
Humanos , Masculino , Feminino , Idoso , Idoso de 80 Anos ou mais , Política Pública , Qualidade de Vida , Saúde do Idoso , Melhoramento Biomédico , Envelhecimento Saudável
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