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2.
Environ Geochem Health ; 46(9): 327, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39012555

RESUMO

The novel bioengineered CuO nanoparticles were successfully synthesized directly using green chemistry, the nontoxic and renewable aqueous extract of waste papaya peel (Carica papaya) as a precursor. The XRD analysis indicated a monoclinic phase of CuO nanoparticles and a size of 20 nm, and the optical absorption analysis showed a peak in the 264 nm range. In TEM, the morphology of the NPs was observed to be almost spherical with a particle size of 15 nm. The CuO nanoparticles showed good efficiency in the degradation of methylene, obtaining up to 50% in 40 min using 6 mg in 60 ml of MB at 10 mg/L. The novel presented in this work derives from using rock minerals, from which we have directly obtained copper salt and copper oxide nanoparticles. This process not only utilizes ecological green chemistry but also offers an economic advantage by directly producing nanoparticles from the mineral instead of purchasing costly pure chemical reagents and employing novel nanomaterials to purify wastewater.


Assuntos
Corantes , Cobre , Nanopartículas Metálicas , Cobre/química , Corantes/química , Nanopartículas Metálicas/química , Poluentes Químicos da Água/química , Catálise , Química Verde/métodos , Carica/química , Mineração , Difração de Raios X , Azul de Metileno/química , Microscopia Eletrônica de Transmissão
3.
Chem Biodivers ; 20(3): e202200554, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36799136

RESUMO

The optimized geometry of palbociclib, (PD 0332991) (8-cyclopentyl-6-ethanoyl-5-methyl-2-(5-(piperazin-1-yl)pyridin-2-ylamino)pyrido[2,3-d]pyrimidin-7(8H)-one), electrostatic potential map, molecular orbitals were calculated using the density functional theory. The geometry was used in a molecular docking study of palbociclib-kinase complexes, results could be explained by the charge of the nitrogen and oxygen atoms within the palbociclib. Energy gap of HOMO-LUMO surfaces, could help to explain the reactivity of the ligand and the hydrogen bonding with three different kinases, two of CDK6 and one of CDK4 type. Docking results are similar and complementary with literature reports using molecular dynamics, were hydrogen bonding was obtained and analyzed. The promiscuity of three kinases with palbociclib was detected by the docking results, thus, palbociclib could be used in other types of cancer besides myeloid leukemia. Some similarities are found with CDK4/CDK6 kinases which allow us to determine that palbociclib could be used to control other resistant inhibitor types of cancer.


Assuntos
Neoplasias , Humanos , Simulação de Acoplamento Molecular , Piperazinas/farmacologia , Piridinas/farmacologia , Inibidores de Proteínas Quinases/farmacologia
4.
Microb Cell Fact ; 15(1): 161, 2016 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-27659593

RESUMO

BACKGROUND: Melanins comprise a chemically-diverse group of polymeric pigments whose function is related to protection against physical and chemical stress factors. These polymers have current and potential applications in the chemical, medical, electronics and materials industries. The biotechnological production of melanins offers the possibility of obtaining these pigments in pure form and relatively low cost. In this study, Escherichia coli strains were engineered to evaluate the production of melanin from supplemented catechol or from glycerol-derived catechol produced by an Escherichia coli strain generated by metabolic engineering. RESULTS: It was determined that an improved mutant version of the tyrosinase from Rhizobium etli (MutmelA), could employ catechol as a substrate to generate melanin. Strain E. coli W3110 expressing MutmelA was grown in bioreactor batch cultures with catechol supplemented in the medium. Under these conditions, 0.29 g/L of catechol melanin were produced. A strain with the capacity to synthesize catechol melanin from a simple carbon source was generated by integrating the gene MutmelA into the chromosome of E. coli W3110 trpD9923, that has been modified to produce catechol by the expression of genes encoding a feedback inhibition resistant version of 3-deoxy-D-arabino-heptulosonate 7-phosphate synthase, transketolase and anthranilate 1,2-dioxygenase from Pseudomonas aeruginosa PAO1. In batch cultures with this strain employing complex medium with 40 g/L glycerol as a carbon source, 1.21 g/L of catechol melanin were produced. The melanin was analysed by employing Fourier transform infrared spectroscopy, revealing the expected characteristics for a catechol-derived polymer. CONCLUSIONS: This constitutes the first report of an engineered E. coli strain and a fermentation process for producing a catechol melanin from a simple carbon source (glycerol) at gram level, opening the possibility of generating a large quantity of this polymer for its detailed characterization and the development of novel applications.

5.
J Transl Med ; 13: 124, 2015 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-25928238

RESUMO

BACKGROUND: Ebola hemorrhagic fever (Ebola) is still a highly lethal infectious disease long affecting mainly neglected populations in sub-Saharan Africa. Moreover, this disease is now considered a potential worldwide threat. In this paper, we present an approach to understand how the basic, clinical and patent knowledge on Ebola is organized and intercommunicated and what leading factor could be shaping the evolution of the knowledge translation process for this disease. METHODOLOGY: A combination of citation network analysis; analysis of Medical heading Subject (MeSH) and Gene Ontology (GO) terms, and quantitative content analysis for patents and scientific literature, aimed to map the organization of Ebola research was carried out. RESULTS: We found six putative research fronts (i.e. clusters of high interconnected papers). Three research fronts are basic research on Ebola virus structural proteins: glycoprotein, VP40 and VP35, respectively. There is a fourth research front of basic research papers on pathogenesis, which is the organizing hub of Ebola research. A fifth research front is pre-clinical research focused on vaccines and glycoproteins. Finally, a clinical-epidemiology research front related to the disease outbreaks was identified. The network structure of patent families shows that the dominant design is the use of Ebola virus proteins as targets of vaccines and other immunological treatments. Therefore, patents network organization resembles the organization of the scientific literature. Specifically, the knowledge on Ebola would flow from higher (clinical-epidemiology) to intermediated (cellular-tissular pathogenesis) to lower (molecular interactions) levels of organization. CONCLUSION: Our results suggest a strong reductionist approach for Ebola research probably influenced by the lethality of the disease. On the other hand, the ownership profile of the patent families network and the main researches relationship with the United State Army suggest a strong involvement of this military institution in Ebola research.


Assuntos
Pesquisa Biomédica , Ebolavirus/fisiologia , Conhecimentos, Atitudes e Prática em Saúde , Militares , Patentes como Assunto , Ontologia Genética , Humanos , Medical Subject Headings , Modelos Teóricos , Estados Unidos
6.
J Transl Med ; 12: 227, 2014 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-25182125

RESUMO

We explored how the knowledge translation and innovation processes are structured when theyresult in innovations, as in the case of liposomal doxorubicin research. In order to map the processes, a literature network analysis was made through Cytoscape and semantic analysis was performed by GOPubmed which is based in the controlled vocabularies MeSH (Medical Subject Headings) and GO (Gene Ontology). We found clusters related to different stages of the technological development (invention, innovation and imitation) and the knowledge translation process (preclinical, translational and clinical research), and we were able to map the historic emergence of Doxil as a paradigmatic nanodrug. This research could be a powerful methodological tool for decision-making and innovation management in drug delivery research.


Assuntos
Antineoplásicos , Difusão de Inovações , Doxorrubicina/análogos & derivados , Descoberta de Drogas , Conhecimento , Pesquisa Translacional Biomédica , Antineoplásicos/isolamento & purificação , Antineoplásicos/uso terapêutico , Doxorrubicina/isolamento & purificação , Doxorrubicina/uso terapêutico , Ontologia Genética , Humanos , Serviços de Informação/organização & administração , Mapas como Assunto , Medical Subject Headings , Neoplasias/tratamento farmacológico , Polietilenoglicóis/isolamento & purificação , Polietilenoglicóis/uso terapêutico
7.
Pharm Nanotechnol ; 11(2): 194-207, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36278457

RESUMO

OBJECTIVE: The objective of this study is to produce a geo-referenced map of the status of R&D in COVID-related studies in the world. METHODS: Spatial mapping of bibliometric data of Cortellis Drug Discovery Intelligence through a spatial bibliometric model with the aid of a GIS (Geographic Information System) called ArcGIS and the software. RESULTS: We show the countries that have the most studies related to COV ID-19 and their degree of collaboration. No drug discovery-related activity was found in South America and Africa. A geo-referenced map of the most active countries in COVID research was constructed as well as conceptual maps of the 11 most representative drugs employed for COVID treatment. CONCLUSION: The georeferenced conceptual maps produced in the present report allow not only to better understand the leading institutions in R&D in COVID-19 related drugs but also to visualize their interactions and research relationships. This could offer, in addition to a coherent, organized multinational effort, the possibility of searching for other drugs that have been employed for other diseases and that, in terms of their conceptual relations, could represent some possibilities for treating the coronavirus SARS-2.


Assuntos
COVID-19 , Humanos , SARS-CoV-2 , Bibliometria
8.
Biomed Eng Online ; 11: 78, 2012 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-23088559

RESUMO

BACKGROUND: Silica nanoparticles are being developed as a host of biomedical and biotechnological applications. For this reason, there are more studies about biocompatibility of silica with amorphous and crystalline structure. Except hydrated silica (opal), despite is presents directly and indirectly in humans. Two sizes of crystalline opal nanoparticles were investigated in this work under criteria of toxicology. METHODS: In particular, cytotoxic and genotoxic effects caused by opal nanoparticles (80 and 120 nm) were evaluated in cultured mouse cells via a set of bioassays, methylthiazolyldiphenyl-tetrazolium-bromide (MTT) and 5-bromo-2'-deoxyuridine (BrdU). RESULTS: 3T3-NIH cells were incubated for 24 and 72 h in contact with nanocrystalline opal particles, not presented significant statistically difference in the results of cytotoxicity. Genotoxicity tests of crystalline opal nanoparticles were performed by the BrdU assay on the same cultured cells for 24 h incubation. The reduction of BrdU-incorporated cells indicates that nanocrystalline opal exposure did not caused unrepairable damage DNA. CONCLUSIONS: There is no relationship between that particles size and MTT reduction, as well as BrdU incorporation, such that the opal particles did not induce cytotoxic effect and genotoxicity in cultured mouse cells.


Assuntos
Apoptose/efeitos dos fármacos , Materiais Biocompatíveis/toxicidade , Sobrevivência Celular/efeitos dos fármacos , Nanopartículas/toxicidade , Dióxido de Silício/toxicidade , Animais , Materiais Biocompatíveis/química , Cristalização , Relação Dose-Resposta a Droga , Teste de Materiais , Camundongos , Células NIH 3T3 , Nanopartículas/química , Dióxido de Silício/química
9.
J Opioid Manag ; 18(5): 399-405, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36226780

RESUMO

The conceptual structure of opioids, based on the bibliometric analysis of 4,935 articles of the Web of Science using the following indices: Science Citation Index Expanded (SCI-EXPANDED), Social Sciences Citation Index (SSCI), Conference Proceedings Citation Index-Science (CPCI-S), Conference Proceedings Citation Index- Social Science and Humanities (CPCI-SSH), Book Citation Index-Science (BKCI-S), Book Citation Index-Social Sciences and Humanities (BKCI-SSH) and Emerging Sources Citation Index (ESCI), was constructed. We analyzed the available articles with the words "Opioids" and "Cancer." We show the evolution and the state of the art in countries where these treatments are implemented. The results were processed identifying the most cited articles to extract the main connections and frequencies of keywords, authors, journals, countries, institutions, and their tendencies and their connection and degree of collaboration. The temporal tendencies, the word cloud, the keyword network, the evolution of words, author's production, and the scientific production by country are analyzed in terms of the increasing frequency in which opioids are employed to treat both cancerous and non-cancerous pain.


Assuntos
Analgésicos Opioides , Neoplasias , Analgésicos Opioides/efeitos adversos , Bibliometria , Humanos , Dor
10.
Artigo em Inglês | MEDLINE | ID: mdl-35742489

RESUMO

The COVID-19 pandemic has resulted in high demand for disinfection technologies. However, the corresponding spray technologies are still not completely optimized for disinfection purposes. There are important problems, like the irregular coverage and dripping of disinfectant solutions on hard and vertical surfaces. In this study, we highlight two major points. Firstly, we discuss the effectiveness of the electrostatic spray deposition (ESD) of nanoparticle-based disinfectant solutions for systematic and long-lasting disinfection. Secondly, we show that, based on the type of material of the substrate, the effectiveness of ESD varies. Accordingly, 12 frequently touched surface materials were sprayed using a range of electrostatic spray system parameters, including ion generator voltage, nozzle spray size and distance of spray. It was observed that for most cases, the surfaces become completely covered with the nanoparticles within 10 s. Acrylic, Teflon, PVC, and polypropylene surfaces show a distinct effect of ESD and non-ESD sprays. The nanoparticles form a uniform layer with better surface coverage in case of electrostatic deposition. Quantitative variations and correlations show that 1.5 feet of working distance, an 80 µm spray nozzle diameter and an ion generator voltage of 3-7 kV ensures a DEF (differential electric field) that corresponds to an optimized charge-to-mass ratio, ensuring efficient coverage of nanoparticles.


Assuntos
COVID-19 , Desinfetantes , COVID-19/prevenção & controle , Desinfecção/métodos , Humanos , Pandemias/prevenção & controle , Eletricidade Estática
11.
J Mater Sci Mater Med ; 22(9): 2097-109, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21744103

RESUMO

Chemotropic proteins guide neuronal projections to their final target during embryo development and are useful to guide axons of neurons used in transplantation therapies. Site-specific delivery of the proteins however is needed for their application in the brain to avoid degradation and pleiotropic affects. In the present study we report the use of Poly (ethylene glycol)-Silica (PEG-Si) nanocomposite gel with thixotropic properties that make it injectable and suitable for delivery of the chemotropic protein semaphorin 3A. PEG-Si gel forms a functional gradient of semaphorin that enhances axon outgrowth of dopaminergic neurons from rat embryos or differentiated from stem cells in culture. It is not cytotoxic and its properties allowed its injection into the striatum without inflammatory response in the short term. Long term implantation however led to an increase in macrophages and glial cells. The inflammatory response could have resulted from non-degraded silica particles, as observed in biodegradation assays.


Assuntos
Dopamina/metabolismo , Nanoestruturas , Neurônios/citologia , Animais , Materiais Biocompatíveis , Gânglios Espinais/citologia , Gânglios Espinais/metabolismo , Neurônios/metabolismo , Polietilenoglicóis , Ratos , Proteínas Recombinantes/administração & dosagem , Semaforina-3A/administração & dosagem , Análise Espectral Raman
12.
Opt Lett ; 35(18): 3087-9, 2010 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-20847787

RESUMO

A simple evaluation of the phase change in a diffracted wave, in terms of the Cornu spiral, is presented to complement the well-known intensity change, which is routinely obtained for this elegant graphical construction of the Fresnel integrals. This is, to the best of our knowledge, the first presentation of this evaluation. It is shown that the phase of a wave diffracted by a slit is equal to the slope of the line tangent to the Cornu spiral, shifted by π/4.

13.
Am J Transl Res ; 11(1): 210-217, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30787980

RESUMO

Computed tomography imaging of the temporomandibular joint was carried out in 22 previously-diagnosed arthritis patients (3 men, 19 women). This descriptive, cross-sectional observational, qualitative study allowed to characterize the type of condylar morphology condition, the space between temporomandibular joint, the erosion of the cortical and osteophytes formation. The joint characteristics found were cortical erosion, osteophytes and decrease of joint space, which reveals, for the first time in the literature, a correlation between arthritis and temporomandibular joint disease.

14.
J Nanosci Nanotechnol ; 8(11): 5733-8, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19198297

RESUMO

Cr ion-polluted industrial water was treated with commercial activated carbon and with either mercaptane- and amine-functionallized silica nanoparticles, revealing that the use of relatively low surface area materials can advantageously compete with high surface area materials, traditionally utilized for removing hazardous metal ions, provided a proper surface functionalization of the nanoparticles is in place. FTIR and SEM characterization of the different materials and stages of the experiments are provided, as well.


Assuntos
Cromo/isolamento & purificação , Resíduos Industriais/prevenção & controle , Nanopartículas/química , Nanotecnologia/métodos , Dióxido de Silício/química , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Água/química , Cristalização/métodos , Substâncias Macromoleculares/química , Teste de Materiais , Conformação Molecular , Nanopartículas/ultraestrutura , Tamanho da Partícula , Propriedades de Superfície , Ultrafiltração/métodos
15.
J Nanosci Nanotechnol ; 8(6): 3142-5, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18681059

RESUMO

The synthesis, characterization and corrosion properties of a novel material, produced by the reaction of silica nanoparticles with a functionalized Phenol-Formaldehyde Resin (PFR), are presented. Carboxylic groups were attached in situ to the PFR skeleton to produce a functionalized resin (PFR-SA), which is then reacted with sol-gel-prepared silica nanoparticles, yielding a novel hybrid (organic/inorganic) material (PFR-SA-nanoSiO2). This hybrid material was characterized by FT-IR, FT-Raman, TGA, DSC, SEM and corrosion tests, whose results showed significant improvement of the thermal properties in comparison with the PFR coating. In addition, the new material was efficient and durable against corrosion of metals, with the anticorrosive performance of PFR-SA and PFR-SA/nanoSiO2 coating films being superior to those of the original PFR coating.

16.
PLoS One ; 12(5): e0178293, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28542584

RESUMO

In this paper, we have identified and analyzed the emergence, structure and dynamics of the paradigmatic research fronts that established the fundamentals of the biomedical knowledge on HIV/AIDS. A search of papers with the identifiers "HIV/AIDS", "Human Immunodeficiency Virus", "HIV-1" and "Acquired Immunodeficiency Syndrome" in the Web of Science (Thomson Reuters), was carried out. A citation network of those papers was constructed. Then, a sub-network of the papers with the highest number of inter-citations (with a minimal in-degree of 28) was selected to perform a combination of network clustering and text mining to identify the paradigmatic research fronts and analyze their dynamics. Thirteen research fronts were identified in this sub-network. The biggest and oldest front is related to the clinical knowledge on the disease in the patient. Nine of the fronts are related to the study of specific molecular structures and mechanisms and two of these fronts are related to the development of drugs. The rest of the fronts are related to the study of the disease at the cellular level. Interestingly, the emergence of these fronts occurred in successive "waves" over the time which suggest a transition in the paradigmatic focus. The emergence and evolution of the biomedical fronts in HIV/AIDS research is explained not just by the partition of the problem in elements and interactions leading to increasingly specialized communities, but also by changes in the technological context of this health problem and the dramatic changes in the epidemiological reality of HIV/AIDS that occurred between 1993 and 1995.


Assuntos
Pesquisa Biomédica/estatística & dados numéricos , Infecções por HIV/patologia , Fármacos Anti-HIV/uso terapêutico , Bibliometria , Pesquisa Biomédica/história , Pesquisa Biomédica/organização & administração , HIV/efeitos dos fármacos , HIV/fisiologia , Infecções por HIV/tratamento farmacológico , Infecções por HIV/fisiopatologia , História do Século XX , Humanos , Modelos Teóricos
17.
Curr Med Chem ; 23(26): 3000-3012, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27530406

RESUMO

An innovative approach to analyze the complexity of translating novel molecular entities and nanomaterials into pharmaceutical alternatives (i.e., knowledge translation, KT) is discussed. First, some key concepts on the organization and translation of the biomedical knowledge (paradigms, homophily, power law distributions, hierarchy, modularity, and research fronts) are reviewed. Then, we propose a model for the knowledge translation (KT) in Drug Discovery that considers the complexity of interdisciplinary communication. Specifically, we address two highly relevant aspects: 1) A successful KT requires the emergence of organized bodies of inter-and transdisciplinary research, and 2) The hierarchical and modular topological organization of these bodies of knowledge. We focused on a set of previously-published studies on KT which rely on a combination of network analysis and computer-assisted analysis of the contents of scientific literature and patents. The selected studies provide a duo of complementary perspectives: the demand of knowledge (cervical cancer and Ebola hemorrhagic fever) and the supply of knowledge (liposomes and nanoparticles to treat cancer and the paradigmatic Doxil, the first nano- drug to be approved).


Assuntos
Desenho de Fármacos , Pesquisa Translacional Biomédica , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Portadores de Fármacos/química , Humanos , Lipossomos/química , Nanoestruturas/química , Neoplasias/tratamento farmacológico
18.
Springerplus ; 5(1): 918, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27386362

RESUMO

Four spatial estimation techniques available in commercial computational packages are evaluated and compared, namely: regularized splines interpolation, tension splines interpolation, inverse distance weighted interpolation, and ordinary Kriging estimation, in order to establish the best representation for the shallow stratigraphic configuration in the city of Aguascalientes, in Central Mexico. Data from 478 sample points along with the software ArcGIS (Environmental Systems Research Institute, Inc. (ESRI), ArcGIS, ver. 9.3, Redlands, California 2008) to calculate the spatial estimates. Each technique was evaluated based on the root mean square error, calculated from a validation between the generated estimates and measured data from 64 sample points which were not used in the spatial estimation process. The present study shows that, for the estimation of the hard-soil layer, ordinary Kriging offered the best performance among the evaluated techniques.

19.
IET Nanobiotechnol ; 10(5): 301-307, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27676378

RESUMO

A green facile method has been successfully used for the synthesis of graphene oxide sheets decorated with silver nanoparticles (rGO/AgNPs), employing graphite oxide as a precursor of graphene oxide (GO), AgNO3 as a precursor of Ag nanoparticles (AgNPs), and geranium (Pelargonium graveolens) extract as reducing agent. Synthesis was accomplished using the weight ratios 1:1 and 1:3 GO/Ag, respectively. The synthesised nanocomposites were characterised by scanning electron microscopy, transmission electron microscopy, atomic force microscopy, X-ray diffraction, UV-visible spectroscopy, Raman spectroscopy, energy dispersive X-ray spectroscopy and thermogravimetric analysis. The results show a more uniform and homogeneous distribution of AgNPs on the surface of the GO sheets with the weight ratio 1:1 in comparison with the ratio 1:3. This eco-friendly method provides a rGO/AgNPs nanocomposite with promising applications, such as surface enhanced Raman scattering, catalysis, biomedical material and antibacterial agent.

20.
IET Nanobiotechnol ; 9(4): 215-9, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26224351

RESUMO

Rice husk was employed as a source for producing silica micro- and nanoparticles through its digestion by soil fauna. Although many physicochemical methods for producing nanostructures have been studied, the biological processes remain mostly unexplored. Alkaline hydrogen peroxide with continuous control of reaction pH allowed removal of lignin bonds while preserving most of the cell wall and the silica present in the rice husk. The accessibility of lignocellulose was achieved without removing appreciable amounts of lignin, so this agricultural byproduct can be employed as feeding material for microarthropods Folsomia candida (Collembola). When these microarthropods are placed on a substrate of treated rice husk, more than 85% of degraded material is obtained, as compared to the untreated rice husk substrate, while the silica particles obtained show a slight decrease in average size.


Assuntos
Artrópodes/metabolismo , Nanopartículas/química , Oryza/metabolismo , Dióxido de Silício/química , Dióxido de Silício/metabolismo , Solo/parasitologia , Animais , Tamanho da Partícula , Solo/química
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