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1.
Polymers (Basel) ; 16(13)2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-39000728

RESUMO

Synthetic plastic polymers are causing considerable emerging ecological hazards. Starch-based biofilms are a potential alternative. However, depending on the natural source and extraction method, the properties of starch can vary, affecting the physicochemical characteristics of the corresponding casted films generated from it. These differences might entail morphological changes at the nanoscale, which can be explored by inspecting their surfaces. Potato (Solanum tuberosum) is a well-known tuber containing a high amount of starch, but the properties of the biofilms extracted from it are dependent on the specific variety. In this research, four Ecuadorian potato varieties (Leona Blanca, Única, Chola, and Santa Rosa) were analyzed and blended with different glycerol concentrations. The amylose content of each extracted starch was estimated, and biofilms obtained were characterized at both macroscopic and nanoscopic levels. Macroscopic tests were conducted to evaluate their elastic properties, visible optical absorption, water vapor permeability, moisture content, and solubility. It was observed that as the glycerol percentage increased, both moisture content and soluble matter increased, while tensile strength decreased, especially in the case of the Chola variety. These results were correlated to a surface analysis using atomic force microscopy, providing a possible explanation based on the topography and phase contrast observations made at the nanoscale.

2.
Cancer Diagn Progn ; 3(6): 616-634, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37927802

RESUMO

Renal neoplasms are highlighted as one of the 10 most common types of cancer. Renal cell carcinoma (RCC) is the most common type of renal cancer, considered the seventh most common type of cancer in the Western world. The most frequently altered genes described as altered are VHL, PBRM1, SETD2, KDM5C, PTEN, BAP1, mTOR, TP53, TCEB1 (ELOC), SMARCA4, ARID1A, and PIK3CA. RCC therapies can be classified in three groups: monoclonal antibodies, tyrosine kinase inhibitors, and mTOR inhibitors. Besides, there are targeted agents to treat RCC. However, frequently patients present side effects and resistance. Even though many multidrug resistance mechanisms already have been reported to RCC, studies focused on revealing new biomarkers as well as more effective antitumor therapies with no or low side effects are very important. Some studies reported that natural products, such as honey, epigallocatechin-3-gallate (EGCG), curcumin, resveratrol, and englerin A showed antitumor activity against RCC. Moreover, nanoscience is another strategy to improve RCC treatment and reduce the side effects due to the improvement in pharmacokinetics and reduction of toxicities of chemotherapies. Taking this into account, we conducted a systemic review of recent research findings on RCC hallmarks, drug resistance, and adjuvant therapies. In conclusion, a range of studies reported that RCC is characterized by high incidence and increased mortality rates because of the development of resistance to standard therapies. Given the importance of improving RCC treatment and reducing adverse effects, nanoscience and natural products can be included in therapeutic strategies.

3.
Polymers (Basel) ; 14(19)2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36236064

RESUMO

The replacement of synthetic polymers by starch biofilms entails a significant potentiality. They are non-toxic materials, biodegradable, and relatively easy to gather from several sources. However, various applications may require physicochemical properties that might prevent the use of some types of starch biofilms. Causes should be explored at the nanoscale. Here we present an atomic force microscopy surface analysis of starch biofilms extracted from the Andean tubers melloco (Ullucus tuberosus), mashua (Tropaeolum tuberosum), oca (Oxalis tuberosa), and potato (Solanum tuberosum) and relate the results to the macroscopic effects of moisture content, water activity, total soluble matter, water vapor permeability, elastic properties, opacity and IR absorption. Characterization reveals important differences at the nanoscale between the starch-based biofilms examined. Comparison permitted correlating macroscopic properties observed to the topography and tapping phase contrast segregation at the nanoscale. For instance, those samples presenting granular topography and disconnected phases at the nanoscale are associated with less elastic strength and more water molecule affinity. As an application example, we propose using the starch biofilms developed as a matrix to dispose of mouthwash and discover that melloco films are quite appropriate for this purpose.

5.
Ciênc. rural (Online) ; 52(6): e20210195, 2022. tab, ilus
Artigo em Inglês | VETINDEX | ID: biblio-1350585

RESUMO

The purpose of this review was to address the applicability of nanotechnology in veterinary medicine, with an emphasis on research in Brazil from 2013 to 2020. Firstly, we introduced to the general aspects of applicability of nanotechnology in veterinary medicine, and lately we pointed the research involving nanoscience performed in Brazil, in the studied period. Nanotechnology is the field of science that has the capacity to organize matter in nanoscale structures (1 to 100 nm), enabling innovations in different areas including biotechnology, agriculture, disease diagnosis, food and clothing industry, electronics, and pharmacological therapies. In veterinary medicine, several studies are being carried out in the world, mainly in the areas that involve search of new treatment options and the development of immunotherapy, as well as in the diagnosis of diseases. In Brazil, it is clear that the use of nanotechnology in veterinary medicine is still incipient, but it can be considered a growing area. In addition, several points have to be reflected and researched, including some adverse effects and implications to validate the safe use of nanotechnology in veterinary medicine. Therefore, this review highlighted the nanotechnology as a promise alternative in the current context of Brazilian technological innovation involving animal health, as well as a possible diagnostic tool and highlighting its potential therapeutic use in disease control in veterinary medicine. Regarding future perspectives, we believed that greater investment in science and technology could contribute to the advancement and strengthening of nanotechnology in Brazil.


O objetivo desta revisão foi abordar a aplicabilidade da nanotecnologia na medicina veterinária, com ênfase nas pesquisas no Brasil de 2013 a 2020. Primeiramente, apresentam-se os aspectos gerais da aplicabilidade da nanotecnologia em medicina veterinária e, posteriormente, apontam-se as pesquisas envolvendo nanociência realizadas no Brasil, no período estudado. A nanotecnologia é o campo da ciência capaz de organizar a matéria em estruturas de nanoescala (1 a 100 nm), permitindo inovações em diferentes áreas, incluindo biotecnologia, agricultura, diagnóstico de doenças, indústria de alimentos e vestuário, eletrônica e terapias farmacológicas. Na medicina veterinária, diversos estudos estão sendo realizados no mundo, principalmente nas áreas que envolvem a busca de novas opções de tratamento e o desenvolvimento de imunoterapia, bem como no diagnóstico de doenças. No Brasil, está claro que o uso da nanotecnologia na medicina veterinária ainda é incipiente, mas pode ser considerada uma área em crescimento. Além disso, vários pontos devem ser refletidos e pesquisados, incluindo alguns efeitos adversos e implicações para validar o uso seguro da nanotecnologia na medicina veterinária. Nesta revisão, destaca-se a nanotecnologia como uma alternativa promissora no atual contexto de inovação tecnológica brasileira, envolvendo saúde animal, o diagnóstico e o potencial uso terapêutico no controle de doenças em medicina veterinária. Em relação às perspectivas futuras, acredita-se que maiores investimentos em ciência e tecnologia são fatores fundamentais a contribuir para o avanço e fortalecimento da nanotecnologia no Brasil.


Assuntos
Medicina Veterinária/tendências , Desenvolvimento Tecnológico , Nanotecnologia/tendências
6.
Water Air Soil Pollut ; 232(10): 435, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34658457

RESUMO

Currently, hundreds of different nanomaterials with a broad application in products that make daily lives a little bit easier, in every aspect, are being produced on an industrial scale at thousands of tons per year. However, several scientists, researchers, politics, and ordinary citizens have stated their concern regarding the life cycle, collateral effects, and final disposal of these cutting-edge materials. This review summarizes, describes, and discusses all manuscripts published in the Journal Citation Reports during the last 10 years, which studied the toxicity or the effects of nanomaterials on human and environmental health. It was observed that 23.62% of the manuscripts analyzed found no ecological or human risks; 54.39% showed that several nanomaterials have toxicological effects on the ecosystems, human, or environmental health. In comparison, only 21.97% stated the nanomaterials had a beneficial impact on those. Although only 54.39% of the manuscripts reported unfavorable effects of nanomaterials on ecosystems, human, or environmental health, it is relevant because the potential damage is invaluable. Therefore, it is imperative to make toxicological studies of nanomaterials with holistic focus under strictly controlled real conditions before their commercialization, to deliver to the market only innocuous and environmentally friendly products.

7.
Sci Total Environ ; 793: 148524, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34182452

RESUMO

Nanotechnology is one of the most relevant scientific areas today due to its multiple applications in fields such as medicine, environmental remediation, information technology and energy conversion. This importance has led to the need to advance in the development of environmentally sustainable and safe nanomaterials by incorporating the principles of green chemistry during their synthesis and in their applications. However, this qualitative framework of thought does not offer minimum criteria for the use of the term "green", and therefore, this adjective is commonly used to refer to bio-based or nanotechnological processes without taking into account their net ecological impact. In this context, environmental sustainability metrics can be applied to nanotechnology to compare, optimize and quantify the environmental sustainability of synthesis procedures. This review provides an overview of green chemistry and its application in nanotechnology, but also an analysis of the use of green chemistry principles in the development of bio-based nanobiotechnology and nanosynthesis, with special emphasis on the use of sustainability's metrics for the quantitative analysis of nanomaterial synthesis protocols. These include: Atom Economy, E-factor, Process Mass Intensity, Energy Intensity, and Life Cycle Analysis.


Assuntos
Recuperação e Remediação Ambiental , Nanoestruturas , Benchmarking , Nanotecnologia
8.
Nanomaterials (Basel) ; 10(2)2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-32012926

RESUMO

Porous Si-SiO2 UV microcavities are used to modulate a broad responsivity photodetector (GVGR-T10GD) with a detection range from 300 to 510 nm. The UV microcavity filters modified the responsivity at short wavelengths, while in the visible range the filters only attenuated the responsivity. All microcavities had a localized mode close to 360 nm in the UV-A range, and this meant that porous Si-SiO2 filters cut off the photodetection range of the photodetector from 300 to 350 nm, where microcavities showed low transmission. In the short-wavelength range, the photons were absorbed and did not contribute to the photocurrent. Therefore, the density of recombination centers was very high, and the photodetector sensitivity with a filter was lower than the photodetector without a filter. The maximum transmission measured at the localized mode (between 356 and 364 nm) was dominant in the UV-A range and enabled the flow of high energy photons. Moreover, the filters favored light transmission with a wavelength from 390 nm to 510 nm, where photons contributed to the photocurrent. Our filters made the photodetector more selective inside the specific UV range of wavelengths. This was a novel result to the best of our knowledge.

9.
CNS Neurol Disord Drug Targets ; 18(1): 44-51, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30394223

RESUMO

BACKGROUND: Alzheimer's disease (AD) is a neurodegenerative disease characterized by the progressive and incapacitating decay of cognitive, neuropsychiatric, and behavioral manifestations. L-tryptophan is the precursor amino acid of serotonin, which is a neurotransmitter responsible for mood balance and the sense of well-being and can be administered in the form of nanoparticles. OBJECTIVE: This study analyzed the effectiveness of L-tryptophan nanoparticles and L-tryptophan on behavioral physiological alterations resulting from AD in animal models. METHODS: The sample consisted of 50 Rattus norvegicus rats, divided in 10 groups with 5 animals each: one negative control (NC), three positive control groups (C3, C7, and C21), three groups treated with L-tryptophan nanoparticles (T3N, T7N, and T21N) at the concentration of 1.5 mg, and three groups treated with L-tryptophan (T3L, T7L, and T21L) at the concentration of 1.5 mg. The rats underwent stereotactic surgery to induce AD through the injection of amyloid beta-amyloid peptide1-42 in the intracerebroventricular region. All rats were submitted to pre- and post-surgery and post-treatment motor behavior evaluation through the Later Water Maze (LWM) and elevated cross-labyrinth (ECL). Histological analysis was performed to verify the presence of senile plaques, and the statistical analysis used the unpaired T-test. RESULTS: Significant intergroup differences were observed in some of the evaluated parameters between treated and untreated groups. CONCLUSION: It was concluded that the treatment with L-tryptophan nanoparticles was beneficial to improve behavioral reactions in the Alzheimer's model.


Assuntos
Doença de Alzheimer/prevenção & controle , Comportamento Animal/efeitos dos fármacos , Triptofano/farmacologia , Doença de Alzheimer/induzido quimicamente , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/administração & dosagem , Animais , Infusões Intraventriculares , Nanopartículas/química , Fragmentos de Peptídeos/administração & dosagem , Placa Amiloide/patologia , Ratos , Triptofano/química
10.
Adv Exp Med Biol ; 1055: 183-211, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29884966

RESUMO

Chemical speciation approaches is an inherent part of metallomics, once metals/metalloids and organic structures need to be currently evaluated for attaining metallomics studies. Then, this chapter focuses on the applications of the chemical speciation applied to the human health risk, food and human diet, drugs, forensic, nanoscience, and geological metallomics, also pointing out the advances in such area. Some aspects regarding sample preparation is commented along this chapter, and some strategies for maintaining the integrity of the metallomics information are also emphasized.


Assuntos
Metaloides/análise , Metaloides/metabolismo , Metais/análise , Metais/metabolismo , Animais , Humanos
11.
Rev. colomb. quím. (Bogotá) ; 45(1): 15-20, ene.-abr. 2016.
Artigo em Espanhol | LILACS | ID: lil-791349

RESUMO

Debido a la creciente producción y uso de nanomateriales para actividades de investigación y desarrollo en Colombia, es necesario establecer una definición del término nanomaterial que facilite la toma de decisiones en torno a iniciativas de carácter regulatorio y de normatividad. Se presenta la definición de nanomateriales para Colombia que ha adoptado el Consejo Nacional Asesor de Nanociencia y Nanotecnología adscrito a la Red Colombiana de Nanociencia y Nanotecnología.


Due to the increasing production and use of nanomaterials in research and development activities in Colombia, it is necessary to define the nanomaterial term in order to facilitate decision-making process regarding initiatives with a regulatory or normative character. This article presents the nanomaterials definition that has been adopted by the National Advisory Council for Nanoscience and Nanotechnology, a Colombian Network of Nanoscience and Nanotechnology.


Dada a crescente produção e utilização de nanomateriais para a pesquisa e desenvolvimiento na Colombia, é urgente estabelecer uma definição do termo de nanomaterial para facilitar a tomada de decisão sobre iniciativas na regulamentação e as leis. É apresentada uma definição de nanomateriais para a Colombia que aprovou o Conselho Consultivo Nacional de Nanociência e Nanotecnologia ligado à Rede Colombiana de Nanociência e Nanotecnologia.

12.
Sensors (Basel) ; 12(6): 8278-300, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22969400

RESUMO

This review article discusses and documents the basic concepts and principles of nano/biosensors. More specifically, we comment on the use of Chemical Force Microscopy (CFM) to study various aspects of architectural and chemical design details of specific molecules and polymers and its influence on the control of chemical interactions between the Atomic Force Microscopy (AFM) tip and the sample. This technique is based on the fabrication of nanomechanical cantilever sensors (NCS) and microcantilever-based biosensors (MC-B), which can provide, depending on the application, rapid, sensitive, simple and low-cost in situ detection. Besides, it can provide high repeatability and reproducibility. Here, we review the applications of CFM through some application examples which should function as methodological questions to understand and transform this tool into a reliable source of data. This section is followed by a description of the theoretical principle and usage of the functionalized NCS and MC-B technique in several fields, such as agriculture, biotechnology and immunoassay. Finally, we hope this review will help the reader to appreciate how important the tools CFM, NCS and MC-B are for characterization and understanding of systems on the atomic scale.


Assuntos
Técnicas Biossensoriais/instrumentação , Microscopia de Força Atômica/métodos , Nanotecnologia/instrumentação , Fenômenos Mecânicos , Silício/química
13.
Int. j. odontostomatol. (Print) ; 4(2): 127-132, ago. 2010.
Artigo em Espanhol | LILACS | ID: lil-596785

RESUMO

El desarrollo científico sin precedentes alcanzado en los últimos años por la nanotecnología ha generado una nueva dimensión en el desarrollo tecnológico, médico y económico que ha marcado un impacto global. Los avances en estrategias de diagnóstico, tratamiento, y prevención de las enfermedades preveen un importante rol de la nanotecnología en el emergente campo aplicado a la odontología denominado nanoodontología. Entre sus principales desafíos destaca el alcanzar una mejor comprensión de las bases fisiopatológicas de las enfermedades, nuevas estrategias de diagnóstico, y el desarrollo de terapias altamente efectivas. La nanotecnología indica ser el camino de la evolución, y el desarrollo de la odontología del siglo 21. Este artículo, presenta las tendencias, y desafíos de nanotecnología aplicada a la odontología, provee de una visión global del desarrollo de la nanoodontología y su impacto futuro.


The unprecedented scientific development achieved in recent years by the nanotechnology has created a new dimension in the technological, medical and economic development set a global impact. Advances in strategies for diagnosis, treatment, and prevention of diseases foresee an important role of the nanotechnology in the emerging field applied to dentistry called nanodentistry. Among its highlights the main challenges to achieve a better understanding of the pathophysiological bases of diseases, new diagnostic strategies, and development of highly effective therapies. Nanotechnology shows to be the path of evolution, and development of dentistry in the 21st century. This article presents the trends and challenges of nanotechnology applied to dentistry, provides an overview of nanodentistry development and its future impact.


Assuntos
Nanotecnologia , Odontologia/tendências , Nanomedicina
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