Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.455
Filtrar
1.
Braz. j. med. biol. res ; 57: e13105, 2024. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1528108

RESUMEN

One of the main challenges of tissue engineering in dentistry is to replace bone and dental tissues with strategies or techniques that simulate physiological tissue repair conditions. This systematic review of in vitro studies aimed to evaluate the influence of the addition of nanohydroxyapatite (NHap) to scaffolds on cell proliferation and osteogenic and odontogenic differentiation of human mesenchymal stem cells. In vitro studies on human stem cells that proliferated and differentiated into odontogenic and osteogenic cells in scaffolds containing NHap were included in this study. Searches in PubMed/MEDLINE, Scopus, Web of Science, OpenGrey, ProQuest, and Cochrane Library electronic databases were performed. The total of 333 articles was found across all databases. After reading and analyzing titles and abstracts, 8 articles were selected for full reading and extraction of qualitative data. Results showed that despite the large variability in scaffold composition, NHap-containing scaffolds promoted high rates of cell proliferation, increased alkaline phosphatase (ALP) activity during short culture periods, and induced differentiation, as evidenced by the high expression of genes involved in osteogenesis and odontogenesis. However, further studies with greater standardization regarding NHap concentration, type of scaffolds, and evaluation period are needed to observe possible interference of these criteria in the action of NHap on the proliferation and differentiation of human stem cells.

2.
Braz. J. Pharm. Sci. (Online) ; 60: e22542, 2024. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1533990

RESUMEN

Abstract We developed poly-ε-caprolactone (PCL)-based nanoparticles containing D-α-tocopherol polyethylene glycol-1000 succinate (TPGS) or Poloxamer 407 as stabilizers to efficiently encapsulate genistein (GN). Two formulations, referred to as PNTPGS and PNPol, were prepared using nanoprecipitation. They were characterized by size and PDI distribution, zeta potential, nanoparticle tracking analysis (NTA), GN association (AE%), infrared spectroscopy (FT-IR), and differential scanning calorimetry (DSC). PNTPGS-GN exhibited a particle size of 141.2 nm, a PDI of 0.189, a zeta potential of -32.9 mV, and an AE% of 77.95%. PNPol-GN had a size of 146.3 nm, a better PDI than PNTPGS-GN (0.150), a less negative zeta potential (-21.0 mV), and an AE% of 68.73%. Thermal and spectrometric analyses indicated that no new compounds were formed, and there was no incompatibility detected in the formulations. Cellular studies revealed that Poloxamer 407 conferred less toxicity to PCL nanoparticles. However, the percentage of uptake decreased compared to the use of TPGS, which exhibited almost 80% cellular uptake. This study contributes to the investigation of stabilizers capable of conferring stability to PCL nanoparticles efficiently encapsulating GN. Thus, the PCL nanoparticle proposed here is an innovative nanomedicine for melanoma therapy and represents a strong candidate for specific pre-clinical and in vivo studies.

3.
J. appl. oral sci ; 32: e20230278, 2024. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1550476

RESUMEN

Abstract Objective The present in vitro study incorporated niobium oxyhydroxide fillers into an experimental high-viscosity bulk-fill resin composite to improve its mechanical performance and provide it a bioactive potential. Methodology Scanning electron microscopy synthesized and characterized 0.5% niobium oxyhydroxide fillers, demonstrating a homogeneous morphology that represented a reinforcement for the feature. Fillers were weighed, gradually added to the experimental resin composite, and homogenized for one minute, forming three groups: BF (experimental high-viscosity bulk-fill resin composite; control), BF0.5 (experimental high-viscosity bulk-fill resin composite modified with 0.5% niobium oxyhydroxide fillers), and BFC (commercial bulk-fill resin composite Beautifil Bulk U, Shofu; positive control). In total, 10 specimens/groups (8 × 2 × 2 mm) underwent flexural strength (FS) tests in a universal testing machine (Instron) (500N). Resin composites were also assessed for Knoop hardness (KH), depth of cure (DoC), degree of conversion (DC), elastic modulus (E), and degree of color change (ΔE). The bioactive potential of the developed resin composite was evaluated after immersing the specimens into a simulated body fluid in vitro solution and assessing them using a Fourier-transformed infrared spectroscope with an attenuated total reflectance accessory. One-way ANOVA, followed by the Tukey's test (p<0.05), determined FS, DC, KH, and ΔE. For DoC, ANOVA was performed, which demonstrated no significant difference between groups (p<0.05). Conclusions The high-viscosity bulk-fill resin composite with 0.5% niobium oxyhydroxide fillers showed promising outcomes as reinforcement agents and performed well for bioactive potential, although less predictable than the commercial resin composite with Giomer technology.

4.
Journal of Pharmaceutical Practice ; (6): 73-77, 2024.
Artículo en Chino | WPRIM | ID: wpr-1006844

RESUMEN

Objective To construct methoxy polyethylene glycol (mPEG) modified gold nanoparticles (AuNPs) loaded with doxorubicin (DOX) AuNPs-mPEG@DOX in order to reduce the toxicity and side effects of DOX. Methods AuNPs-mPEG@DOX was prepared and characterized by Z-Average, Zeta potential and UV-Vis spectroscopy. The impact of thiol-linked DOX (HS-DOX) at various dosage concentrations on the drug adsorption rate and drug loading of AuNPs-mPEG@DOX was investigated. Furthermore, a HPLC method was developed to accurately determine the content of unadsorbed HS-DOX in AuNPs-mPEG@DOX. The specificity, linearity, precision, stability and average recovery of this method were thoroughly investigated. The cytotoxic effect of AuNPs-mPEG@DOX on MCF-10A and MCF-7 cells was evaluated using a CCK-8 assay. Results AuNPs-mPEG@DOX was successfully prepared with Z-Average of (46.12±0.49) nm, Zeta potential of (18.60±1.51) nm and the maximum absorption wavelength of 530 nm. An efficient HPLC method for the detection of unadsorbed HS-DOX in AuNPs-mPEG@DOX was devised. The optimal dosage concentration of HS-DOX for AuNPs-mPEG@DOX was determined to be 11.18 μg/ml, resulting in a drug adsorption rate of (9.21±2.88)% and a drug loading rate of (2.01±0.62)%. Cytotoxicity experiments demonstrated that AuNPs-mPEG@DOX significantly reduced the toxic and side effects of DOX on normal breast cells. Additionally, AuNPs-mPEG@DOX and free DOX exhibited comparable cytotoxic effects on breast tumor cells when DOX concentration was equal to or greater than 4.75 μmol/L. Conclusion AuNPs-mPEG@DOX effectively reduce the toxicity of DOX, providing a reference for future research on reducing the toxicity of AuNPs-linked drugs.

5.
Journal of Sun Yat-sen University(Medical Sciences) ; (6): 206-215, 2024.
Artículo en Chino | WPRIM | ID: wpr-1016441

RESUMEN

ObjectiveTo investigate the bactericidal effect of loaded multifunctional povidoneiodine-nanometer selenium (PVP-I@Se) disinfectant on Staphylococcus aureus (SA) and methicillin-resistant Staphylococcus aureus (MRSA), and to provide an experimental basis for the reduction of surgical site infection (SSI). MethodsThe control group was the povidone iodine (PVP-I) group with different concentrations of iodine (50, 75, 100, 200 and 400 μg/mL). The PVP-I@Se group (experimental group) was the PVP-I group further supplemented with 2 μg/mL Selenium nanoparticles (SeNPs). Then we compared the bactericidal effect of the two groups of disinfectant solutions on SA and MRSA by examining the minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), the shortest sterilization time at a concentration of 50 μg/mL iodine and the inhibition zone diameters at concentrations of 200 μg/mL and 400 μg/mL iodine. ResultsMIC values of PVP-I against SA and MRSA were both 79.17 μg/mL, and those of PVP-I@Se were 54.17 and 70.83 μg/mL, respectively. MBC values of PVP-I against SA and MRSA were 129.17 and 150.00 μg/mL, respectively, and those of PVP-I@Se were 70.83 and 87.50 μg/mL, respectively. At a concentration of 50 μg/mL iodine, the shortest sterilization time of PVP-I for SA and MRSA was 130 s and 140 s, respectively, and that of PVP-I@Se was 65 s and 75 s, respectively. At a concentration of 200 μg/ml iodine, the inhibition zone diameters of PVP-I for SA and MRSA were 7.67 mm and 8.33 mm, and those of PVP-I@Se were both 9.50 mm. At a concentration of 400 μg/mL iodine, the inhibition zone diameters of PVP-I for SA and MRSA were 9.00 mm and 9.33 mm, and those of PVP-I@Se were 11.67 mm and 12.00 mm, respectively. ConclusionsPVP-I with different concentrations of 50, 75, 100, 200 and 400 μg/mL iodine supplemented with 2 μg/mL SeNPs have better and faster bactericidal effect on SA and MRSA. When combined with SeNPs, PVP-I can enhance the bactericidal activity against SA and MRSA, but with better sensitizing effect on SA than MRSA and higher demand of iodine concentration (400 μg/mL) for sensitizing effect on MRSA. This study provides a theoretical basis for selecting optimal concentration and action time of the disinfectant, thus reducing SSI.

6.
Chinese Pharmacological Bulletin ; (12): 125-132, 2024.
Artículo en Chino | WPRIM | ID: wpr-1013614

RESUMEN

Aim To prepare tripterygium glycoside nanoparticles and probe into their therapeutic effect on collagen-induced arthritis ( CIA) rats. Methods Tripterygium glycosides polyglycoside nanoparticles were prepared by thin film dispersion method and their quality was assessed. The CIA model was established and drug intervention performed. The body weight, toe swelling degree and arthritis index were measured. The pathological changes of the organs, knee and ankle synovium were observed. The serum levels of kidney function and inflammatory cytokine expression were detected in rats. Results The prepared tripterygium wil-fordii polyglycoside nanoparticles were round particles with uniform distribution and stable properties under electron microscope. Compared with the model group, the swelling of the left and right toes of medication group significantly decreased (P < 0. 01), and the ar-thritis index markedly decreased ( P < 0. 01). Among them, the efficacy of the TG-NPs group was better than that of the TG group. Compared with the normal group, the indexes of heart, spleen, kidney and testis all significantly decreased (P <0. 05, P<0.01). TG-NPs group had a significantly reduced pathological ankle-joint injury in knee cartilage and increased apoptotic synovial cells. Compared with the model group, the serum levels of ALT and BUN and CRE in TG-NPs group were significantly lower (P < 0. 05 ), and IL-1β, TNF-α and IL-6 levels decreased significantly (P <0. 05). Conclusions TG-NPs have good therapeutic effect on CIA through induction of synovial cell apoptosis and decrease of the expression of inflammatory cytokines. By intravenous injection of blood circula-tion, slow and controlled release of drugs can be achieved, the first pass effect caused by oral drug can be avoided, the viscera toxicity can be reduced, which provides an experimental basis for the development of new nanoagents for the treatment of rheumatoid arthritis.

7.
Journal of Prevention and Treatment for Stomatological Diseases ; (12): 257-265, 2024.
Artículo en Chino | WPRIM | ID: wpr-1013086

RESUMEN

Objective@#To investigate the effects of PssL-NAC reactive oxygen species (ROS)-responsive nanoparticles on intracellular ROS production, inflammatory factor levels, collagen production, cell function and Toll-like receptor 4 (TLR4), NF-κB nuclear factor-κB (p65) pathway protein expression in human gingival fibroblasts (HGFs) induced by Porphyromonas gingivalis-lipopolysaccharide (P.g-LPS).@*Methods@#This study was reviewed and approved by the ethics committee. PssL-NAC microspheres containing oil soluble antioxidant N-acetylcysteine (NAC) were obtained by connecting the hydrophobic end of polycaprolactone (PCL) and the hydrophilic end of polyethylene glycol (PEG) via thioketal (TK) bonds in response to ROS, and self loading in the aqueous and oil phases. After preparation of the PssL-NAC microspheres and aqueous NAC solution, successful synthesis of the nanoparticles was verified by transmission electron microscopy. Then, HGFs were exposed to P.g-LPS (0, 5, or 10 μg/mL), P.g-LPS (0, 5, or 10 μg/mL)+NAC, and P.g-LPS (0, 5, or 10 μg/mL)+PssL-NAC, and the ROS levels in the different groups were observed under confocal microscopy to determine the concentration of P.g-LPS for use in subsequent experiments. The groups were as follows: control group (no treatment), P.g-LPS group (HGFs treated with P.g-LPS), NAC group (HGFs treated with P.g-LPS and NAC), and PssL-NAC group (HGFs treated with P.g-LPS and PssL-NAC). Cell counting kit-8 (CCK-8) assays verified the biosafety of PssL-NAC. The ROS levels in the different groups were detected by DCFH-DA probes and observed via confocal microscopy. Real-time qPCR (RT-qPCR) was used to monitor the gene expression levels of the intracellular inflammatory cytokines interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), collagen 1 (COL1) and collagen 3 (COL3). The effect of PssL-NAC on the migration of HGFs was observed via the scratch test. The protein expression of TLR4-NF-κB, and phosphorylated p65 (p-p65) in the TLR4-NF-κB pathway was evaluated by Western blot.@*Results@#PssL-NAC had no significant effect on HGF proliferation (P>0.05). At elevated P.g-LPS concentrations, PssL-NAC maintained intracellular ROS levels approximately twice those in the control group (P<0.001). PssL-NAC significantly decreased P.g-LPS-induced IL-6 (P<0.001) and TNF-α (P<0.001) gene expression and increased COL1 gene expression (P<0.001). After P.g-LPS stimulation, PssL-NAC restored cell migration to the control level (P>0.05) and decreased the protein expression of TLR4 (P<0.001), p65 (P = 0.006), and p-p65 (P = 0.017) in the TLR4-NF-κB pathway.@*Conclusion@#PssL-NAC maintains the appropriate intracellular ROS concentration, alleviates P.g-LPS-induced inflammation in HGFs through the TLR4-NF-κB pathway, and restores the cell functions of collagen production and migration in an inflammatory environment.

8.
Journal of Prevention and Treatment for Stomatological Diseases ; (12): 241-248, 2024.
Artículo en Chino | WPRIM | ID: wpr-1013084

RESUMEN

@#Oral plaque biofilms are one of the bases for the survival and metabolism of different bacteria. With the emergence of drug-resistant bacteria due to antibiotic abuse, the prevention and treatment of plaque biofilm-associated oral diseases are becoming increasingly difficult. Although some research progress has been made in the field of biofilm formation and destruction, there is still a lack of effective clinical therapies for plaque biofilm-associated oral diseases. Metal nanoenzymes possess the physical properties of nanoparticles and exhibit catalytic activity similar to that of natural enzymes. The nanoscale size of metal nanoenzymes provides a greater specific surface area to help reactive oxygen species spread rapidly to active catalytic sites and improve the antioxidant properties of nanoenzymes. Additionally, metal nanoenzymes are easy to produce using different methods, such as electrochemical reduction, solvent thermal synthesis and microwave-assisted synthesis. Moreover, metal nanoenzymes can produce a high concentration of hydroxyl radicals, catalyze plaque biofilm degradation, lyse glucan and inhibit biofilm formation by oxidative stress reactions, as well as kill bacteria by releasing metal ions. Thus, metal nanoenzymes are expected to become a new option for the prevention and treatment of oral plaque biofilm-associated diseases. However, metal nanoenzymes can enter organisms through oral, intravenous and respiratory routes, triggering potential toxic effects such as pulmonary toxicity, hepatotoxicity and neurotoxicity. In a complex biological environment, the occurrence of metal nanoenzymes toxicity may involve multiple mechanisms, and the mechanism of action and safety need to be thoroughly investigated. In this paper, we intend to describe the research progress on metal nanoenzymes through an overview of their properties, antibacterial mechanisms, biotoxicity and applications in the prevention and treatment of oral plaque biofilm-related diseases, which may provide new ideas for the prevention and treatment of these diseases.

9.
Acta Pharmaceutica Sinica B ; (6): 854-868, 2024.
Artículo en Inglés | WPRIM | ID: wpr-1011257

RESUMEN

Immune evasion has made ovarian cancer notorious for its refractory features, making the development of immunotherapy highly appealing to ovarian cancer treatment. The immune-stimulating cytokine IL-12 exhibits excellent antitumor activities. However, IL-12 can induce IFN-γ release and subsequently upregulate PDL-1 expression on tumor cells. Therefore, the tumor-targeting folate-modified delivery system F-DPC is constructed for concurrent delivery of IL-12 encoding gene and small molecular PDL-1 inhibitor (iPDL-1) to reduce immune escape and boost anti-tumor immunity. The physicochemical characteristics, gene transfection efficiency of the F-DPC nanoparticles in ovarian cancer cells are analyzed. The immune-modulation effects of combination therapy on different immune cells are also studied. Results show that compared with non-folate-modified vector, folate-modified F-DPC can improve the targeting of ovarian cancer and enhance the transfection efficiency of pIL-12. The underlying anti-tumor mechanisms include the regulation of T cells proliferation and activation, NK activation, macrophage polarization and DC maturation. The F-DPC/pIL-12/iPDL-1 complexes have shown outstanding antitumor effects and low toxicity in peritoneal model of ovarian cancer in mice. Taken together, our work provides new insights into ovarian cancer immunotherapy. Novel F-DPC/pIL-12/iPDL-1 complexes are revealed to exert prominent anti-tumor effect by modulating tumor immune microenvironment and preventing immune escape and might be a promising treatment option for ovarian cancer treatment.

10.
Braz. j. biol ; 842024.
Artículo en Inglés | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469304

RESUMEN

Abstract Nanoparticles are considered viable options in the treatment of cancer. This study was conducted to investigate the effect of magnetite nanoparticles (MNPs) and magnetite folate core shell (MFCS) on leukemic and hepatocarcinoma cell cultures as well as their effect on the animal model of acute myelocytic leukemia (AML). Through current study nanoparticles were synthesized, characterized by various techniques, and their properties were studied to confirm their nanostructure. Invivo study, nanoparticles were evaluated to inspect their cytotoxic activity against SNU-182 (human hepatocellular carcinoma), K562 (human leukemia), and THLE2 (human normal epithelial liver) cells via MTT test. Apoptotic signaling proteins Bcl-2 and Caspase-3 expression were inspected through RT-PCR method. A cytotoxic effect of MNPs and MFCS was detected in previous cell cultures. Moreover, the apoptosis was identified through significant up-regulation of caspase-3, with Bcl-2 down-regulation. Invitro study, AML was induced in rats by N-methyl-N-nitrosourea followed by oral treatment with MNPS and MFCS. Biochemical indices such as aspartate and alanine amino transferases, and lactate dehydrogenase activities, uric acid, complete blood count, and Beta -2-microglubulin were assessed in serum. Immunophenotyping for CD34 and CD38 detection was performed. Liver, kidney, and bone marrow were microscopically examined. Bcl-2 promoter methylation, and mRNA levels were examined. Although, both MNPs and MFCS depict amelioration in biochemical parameters, MFCS alleviated them toward normal control. Anticancer activity of MNPs and MFCS was approved especially for AML. Whenever, administration of MFCS was more effective than MNPs. The present work is one of few studies used MFCS as anticancer agent.


Resumo Nanopartículas são consideradas opções viáveis no tratamento do câncer. Este estudo foi conduzido para investigar o efeito de nanopartículas de magnetita (MNPs) e núcleo de folato de magnetita (MFCS) em culturas de células leucêmicas e de hepatocarcinoma, bem como seu efeito no modelo animal de leucemia mielocítica aguda (LMA). Através do atual estudo, nanopartículas foram sintetizadas, caracterizadas por várias técnicas, e suas propriedades foram estudadas para confirmar sua nanoestrutura. No estudo in vivo, as nanopartículas foram avaliadas para inspecionar sua atividade citotóxica contra células SNU-182 (carcinoma hepatocelular humano), K562 (leucemia humana) e THLE2 (fígado epitelial humano normal) por meio do teste MTT. A expressão das proteínas sinalizadoras apoptóticas Bcl-2 e Caspase-3 foram inspecionadas através do método RT-PCR. Um efeito citotóxico de MNPs e MFCS foi detectado em culturas de células anteriores. Além disso, a apoptose foi identificada por meio de regulação positiva significativa da Caspase-3, com regulação negativa de Bcl-2. No estudo in vitro, a AML foi induzida em ratos por N-metil-N-nitrosoureia seguida por tratamento oral com MNPS e MFCS. Índices bioquímicos como aspartato e alanina aminotransferases e atividades de lactato desidrogenase, ácido úrico, hemograma completo e Beta-2-microglubulina foram avaliados no soro. A imunofenotipagem para detecção de CD34 e CD38 foi realizada. Fígado, rim e medula óssea foram examinados microscopicamente. A metilação do promotor Bcl-2 e os níveis de mRNA foram examinados. Embora tanto os MNPs quanto os MFCS representem uma melhora nos parâmetros bioquímicos, o MFCS os aliviou em direção ao controle normal. A atividade anticâncer de MNPs e MFCS foi aprovada especialmente para AML. Sempre, a administração de MFCS foi mais eficaz do que MNPs. O presente trabalho é um dos poucos estudos que utilizou o MFCS como agente anticâncer.

11.
Braz. j. biol ; 842024.
Artículo en Inglés | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469372

RESUMEN

Abstract Nanoparticles (NPs) are insoluble particles with a diameter of fewer than 100 nanometers. Two main methods have been utilized in orthodontic therapy to avoid microbial adherence or enamel demineralization. Certain NPs are included in orthodontic adhesives or acrylic resins (fluorohydroxyapatite, fluorapatite, hydroxyapatite, SiO2, TiO2, silver, nanofillers), and NPs (i.e., a thin layer of nitrogen-doped TiO2 on the bracket surfaces) are coated on the surfaces of orthodontic equipment. Although using NPs in orthodontics may open up modern facilities, prior research looked at antibacterial or physical characteristics for a limited period of time, ranging from one day to several weeks, and the limits of in vitro studies must be understood. The long-term effectiveness of nanotechnology-based orthodontic materials has not yet been conclusively confirmed and needs further study, as well as potential safety concerns (toxic effects) associated with NP size.


Resumo Nanopartículas (NPs) são partículas insolúveis com diâmetro inferior a 100 nanômetros. Dois métodos principais têm sido utilizados na terapia ortodôntica para evitar a aderência microbiana ou a desmineralização do esmalte: NPs são incluídas em adesivos ortodônticos ou resinas acrílicas (fluoro-hidroxiapatita, fluorapatita, hidroxiapatita, SiO2, TiO2, prata, nanopreenchimentos) e NPs são revestidas nas superfícies de equipamentos ortodônticos, ou seja, uma camada fina de TiO2 dopado com nitrogênio nas superfícies do braquete. Embora o uso de NPs em ortodontia possa tornar acessível modernos recursos, pesquisas anteriores analisaram as características antibacterianas ou físicas por um período limitado de tempo, variando de 24 horas a várias semanas, por isso devem ser compreendidos os limites dos estudos in vitro. A eficácia de longo prazo de materiais ortodônticos com base em nanotecnologia ainda não foi confirmada de forma conclusiva, o que exige mais estudos, bem como potenciais preocupações de segurança (efeitos tóxicos) associadas ao tamanho da NP.

12.
Braz. j. biol ; 84: e253183, 2024. tab, graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1355858

RESUMEN

Abstract Nanoparticles are considered viable options in the treatment of cancer. This study was conducted to investigate the effect of magnetite nanoparticles (MNPs) and magnetite folate core shell (MFCS) on leukemic and hepatocarcinoma cell cultures as well as their effect on the animal model of acute myelocytic leukemia (AML). Through current study nanoparticles were synthesized, characterized by various techniques, and their properties were studied to confirm their nanostructure. Invivo study, nanoparticles were evaluated to inspect their cytotoxic activity against SNU-182 (human hepatocellular carcinoma), K562 (human leukemia), and THLE2 (human normal epithelial liver) cells via MTT test. Apoptotic signaling proteins Bcl-2 and Caspase-3 expression were inspected through RT-PCR method. A cytotoxic effect of MNPs and MFCS was detected in previous cell cultures. Moreover, the apoptosis was identified through significant up-regulation of caspase-3, with Bcl-2 down-regulation. Invitro study, AML was induced in rats by N-methyl-N-nitrosourea followed by oral treatment with MNPS and MFCS. Biochemical indices such as aspartate and alanine amino transferases, and lactate dehydrogenase activities, uric acid, complete blood count, and Beta -2-microglubulin were assessed in serum. Immunophenotyping for CD34 and CD38 detection was performed. Liver, kidney, and bone marrow were microscopically examined. Bcl-2 promoter methylation, and mRNA levels were examined. Although, both MNPs and MFCS depict amelioration in biochemical parameters, MFCS alleviated them toward normal control. Anticancer activity of MNPs and MFCS was approved especially for AML. Whenever, administration of MFCS was more effective than MNPs. The present work is one of few studies used MFCS as anticancer agent.


Resumo Nanopartículas são consideradas opções viáveis ​​no tratamento do câncer. Este estudo foi conduzido para investigar o efeito de nanopartículas de magnetita (MNPs) e núcleo de folato de magnetita (MFCS) em culturas de células leucêmicas e de hepatocarcinoma, bem como seu efeito no modelo animal de leucemia mielocítica aguda (LMA). Através do atual estudo, nanopartículas foram sintetizadas, caracterizadas por várias técnicas, e suas propriedades foram estudadas para confirmar sua nanoestrutura. No estudo in vivo, as nanopartículas foram avaliadas para inspecionar sua atividade citotóxica contra células SNU-182 (carcinoma hepatocelular humano), K562 (leucemia humana) e THLE2 (fígado epitelial humano normal) por meio do teste MTT. A expressão das proteínas sinalizadoras apoptóticas Bcl-2 e Caspase-3 foram inspecionadas através do método RT-PCR. Um efeito citotóxico de MNPs e MFCS foi detectado em culturas de células anteriores. Além disso, a apoptose foi identificada por meio de regulação positiva significativa da Caspase-3, com regulação negativa de Bcl-2. No estudo in vitro, a AML foi induzida em ratos por N-metil-N-nitrosoureia seguida por tratamento oral com MNPS e MFCS. Índices bioquímicos como aspartato e alanina aminotransferases e atividades de lactato desidrogenase, ácido úrico, hemograma completo e Beta-2-microglubulina foram avaliados no soro. A imunofenotipagem para detecção de CD34 e CD38 foi realizada. Fígado, rim e medula óssea foram examinados microscopicamente. A metilação do promotor Bcl-2 e os níveis de mRNA foram examinados. Embora tanto os MNPs quanto os MFCS representem uma melhora nos parâmetros bioquímicos, o MFCS os aliviou em direção ao controle normal. A atividade anticâncer de MNPs e MFCS foi aprovada especialmente para AML. Sempre, a administração de MFCS foi mais eficaz do que MNPs. O presente trabalho é um dos poucos estudos que utilizou o MFCS como agente anticâncer.


Asunto(s)
Animales , Ratas , Nanopartículas de Magnetita , Neoplasias Hepáticas , Compuestos Férricos , Ácido Fólico
13.
Braz. j. biol ; 84: e257070, 2024. tab, ilus
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1360228

RESUMEN

Nanoparticles (NPs) are insoluble particles with a diameter of fewer than 100 nanometers. Two main methods have been utilized in orthodontic therapy to avoid microbial adherence or enamel demineralization. Certain NPs are included in orthodontic adhesives or acrylic resins (fluorohydroxyapatite, fluorapatite, hydroxyapatite, SiO2, TiO2, silver, nanofillers), and NPs (i.e., a thin layer of nitrogen-doped TiO2 on the bracket surfaces) are coated on the surfaces of orthodontic equipment. Although using NPs in orthodontics may open up modern facilities, prior research looked at antibacterial or physical characteristics for a limited period of time, ranging from one day to several weeks, and the limits of in vitro studies must be understood. The long-term effectiveness of nanotechnology-based orthodontic materials has not yet been conclusively confirmed and needs further study, as well as potential safety concerns (toxic effects) associated with NP size.


Nanopartículas (NPs) são partículas insolúveis com diâmetro inferior a 100 nanômetros. Dois métodos principais têm sido utilizados na terapia ortodôntica para evitar a aderência microbiana ou a desmineralização do esmalte: NPs são incluídas em adesivos ortodônticos ou resinas acrílicas (fluoro-hidroxiapatita, fluorapatita, hidroxiapatita, SiO2, TiO2, prata, nanopreenchimentos) e NPs são revestidas nas superfícies de equipamentos ortodônticos, ou seja, uma camada fina de TiO2 dopado com nitrogênio nas superfícies do braquete. Embora o uso de NPs em ortodontia possa tornar acessível modernos recursos, pesquisas anteriores analisaram as características antibacterianas ou físicas por um período limitado de tempo, variando de 24 horas a várias semanas, por isso devem ser compreendidos os limites dos estudos in vitro. A eficácia de longo prazo de materiais ortodônticos com base em nanotecnologia ainda não foi confirmada de forma conclusiva, o que exige mais estudos, bem como potenciais preocupações de segurança (efeitos tóxicos) associadas ao tamanho da NP.


Asunto(s)
Ortodoncia , Desmineralización , Esmalte Dental , Nanopartículas , Antiinfecciosos
14.
Medicina (Ribeirao Preto, Online) ; 56(4)dez. 2023. tab, ilus
Artículo en Inglés | LILACS | ID: biblio-1538188

RESUMEN

Background: This study evaluated the effects of zein nanoparticles with resveratrol on neuroinflammation caused by Alzheimer's disease. Method: The sample consisted of 30 animals divided into control (C), positive control (CP), white nanoparticles (NB), resveratrol nanoparticles (NR) and resveratrol (R) groups. The animals received 10 mg/kg of resveratrol or nanoparticles according to the group, daily, for 15 days, oral administration. Afterward, they were submitted to immunohistochemical (IHC) analyses. Results: the IHC showed that there was no change in the morphological brain composition in the NR and C groups. Conversely, in the CP, NB, and R groups, changes in the deposition of Anti Tau were observed. The NR group showed a normal projection of taurine in the axon, which was not presented in the same way in the other groups. The CD68 marker showed no microglial activation in the R and C groups. Quantitative analyses of Anti Beta-Amyloid in the NR group showed a statistical difference com-pared to the CP, NB, and R groups, whereas the Anti Tau analysis showed a significant difference between the CP and NR groups. The CD68 marker showed a significant difference between the C and NR groups. The analysis of cy-tokines showed a significant difference in TNF-α between the C and CP groups, C and NB groups, CP and NR groups, and NB and NR groups. IL-6 and InF-δ showed no significant difference between all groups. IL-10 showed significant differences between the C and NR groups, C and R groups, and CP and NR groups. Conclusion: NR prevented the evolution of neuroinflammation(AU).


Introdução: Este estudo avaliou os efeitos das nanopartículas de zeína com resveratrol na neuroinflamação causada pela doença de Alzheimer. Método: A amostra consistiu em 30 animais divididos em grupos de controle (C), controle positivo (CP), nanopartículas brancas (NB), nanopartículas de resveratrol (NR) e resveratrol (R). Os animais receberam 10 mg/kg de resveratrol ou nanopartículas de acordo com o grupo, diariamente, por 15 dias, por via oral. Em seguida, foram submetidos a análises imuno-histoquímicas (IHC). Resultados: A IHC mostrou que não houve alteração na composição morfológica do cérebro nos grupos NR e C. Por outro lado, nos grupos CP, NB e R, foram observadas alterações na deposição de Anti Tau. O grupo NR mostrou uma projeção normal de taurina no axônio, que não se apresentou da mesma forma nos outros grupos. O marcador CD68 não mostrou ativação microglial nos grupos R e C. As análises quantitativas do antibeta-amiloide no grupo NR mostraram uma diferença estatística quando comparadas aos grupos CP, NB e R, enquanto a análise do antitau mostrou uma diferença significativa entre os grupos CP e NR. O marcador CD68 mostrou uma diferença significativa entre os grupos C e NR. A análise das citocinas mostrou uma diferença significativa no TNF-α entre os grupos C e CP, C e NB, CP e NR, e NB e NR. IL-6 e InF-δ não apresentaram diferença significativa entre todos os grupos. A IL-10 apresentou diferenças significativas entre os grupos C e NR, C e R, e CP e NR. Conclusão: A NR impediu a evolução da neuroinflamação (AU).


Asunto(s)
Animales , Nanopartículas , Enfermedad de Alzheimer , Resveratrol
15.
Bol. latinoam. Caribe plantas med. aromát ; 22(6): 821-836, nov. 2023. ilus, tab, graf
Artículo en Inglés | LILACS | ID: biblio-1554240

RESUMEN

The present study thus aimed at the development and physicochemical characterization of solid lipid nanoparticles loaded with crude extract of Piper corcovadensis roots (SLN - CEPc) and chitosan - coated solid lipid nanoparticles loaded with crude extract of P. corcovadensis roots (C - SLN - CEPc), as well as the determination of its antimycobacterial activity against Mycobacterium tuberculosis H37Rv, its cytotoxicity against the Vero cell line and evaluation in the hemolysis assay. Both formulat ions containing the encapsulated extract showed high encapsulation efficiency, formed by a monodispersed system with small and spherical particles, and there was no aggregation of particles. In the biological assays, SLN - CEPc and C - SLN - CEPc showed promisin g anti - M. tuberculosis activity with a minimum inhibitory concentration (MIC) of 12.5 µg/mL, whereas the cytotoxic concentrations obtained at 50% (CC 50 ) in Vero cells were 60.0 and 70.0 µg/mL, respectively. Therefore, nanoencapsulation showed satisfactory results, justifying its usage in the development of new products.


El presente estudio apuntó al desarrollo y caracterización fisicoquímica de na nopartículas lípidas en estado sólido, cargadas con extracto crudo de raíz de Piper c orcovadensis (SLN - CEPc) y nanopartículas lípidas en estado sólido cubiertas con quitosano cargadas co n extracto crudo de raíz de P. corcovadensis (C - SLN - CEPc), así como la determinación de su actividad antimico bacterial contra Mycobacterium tuberculosis H37Rv, su citotoxicidad contra la línea celular Vero y su evaluación en ensayo de hemólisis. Ambas formulaciones que contenían el extracto encapsulado mostraron alta eficien cia de encapsulación, formado por un sistema monodispersado con pequeñas partículas esféricas, y no hubo agregación de partículas. En los ensayos biológicos, SLN - CEPc y C - SLN - CEPc mostraron un a prometedora actividad anti - M. tuberculosis con una mínima conc entración inhibitoria (MIC) de 12,5 µg/mL, mientras que las concentraciones citotóxicas obtenidas al 50% (CC 50 ) en células Vero estuvo en 60,0 y 70,0 µg/mL, respectivamente. Por lo tanto, la nanoencapsulación mostró resultados satisfactorios, justificando su uso en el desarrollo de nuevos productos.


Asunto(s)
Extractos Vegetales/química , Piper/química , Mycobacterium tuberculosis/efectos de los fármacos , Extractos Vegetales/administración & dosificación , Sistema de Administración de Fármacos con Nanopartículas
16.
Braz. dent. j ; 34(4): 115-126, July-Aug. 2023. tab, graf
Artículo en Inglés | LILACS-Express | LILACS, BBO | ID: biblio-1520337

RESUMEN

Abstract This study was aimed at analyzing the surface properties of a universal resin composite and evaluating the effect of preheating on its physicochemical properties. Two commercial resin composites were used under two conditions: Filtek Universal Restorative (UR); UR preheated (URH); Filtek Supreme (FS) and FS preheated (FSH). The film thickness (FT) test (n = 10) was done using two glass slabs under compression. Flexural strength (FLS) and modulus (FLM) were evaluated using a three-point flexion test (n = 10). Polymerization shrinkage stress (PSS) was evaluated in a universal testing machine (n = 5). Gap width (GW) between composite and mold was measured in internally polished metallic molds (n = 10). The degree of conversion (DC) was evaluated by Fourier Transform Infrared spectroscopy (n = 3). The morphology of the filler particles was checked by scanning electron microscope (SEM) and EDX analysis. Surface gloss (SG) and surface roughness (SR) were evaluated before and after mechanical brushing (n = 10). The outcomes were submitted to 2-way ANOVA and Tukey's test (α = 0.05). Lower mean values of FT were observed for the preheated groups when compared to the non-preheated groups. URH and FSH showed higher mean values of FLS and FLM when compared with UR and FS. No differences were observed between groups in the PSS test. The GW was higher for the UR and FS groups when compared with URH and FSH. The DC was higher for preheated resin composites when compared to the non-preheated groups. The SR of the UR composite was higher than the FS after mechanical brushing, while the SG was higher for the FS groups. In conclusion, the universal resin composite tested generally presented similar physicochemical properties compared with the nanofilled resin composite and either similar or slightly inferior surface properties. The preheating improved or maintained all properties evaluated.


Resumo Neste estudo avaliou-se propriedades físico-químicas e de superfície de um compósito universal pré-aquecido e comparado a um compósito convencional. Foram utilizados dois compósitos comerciais: Filtek Universal Restorative (UR); UR pré-aquecido (URH); Filtek Supreme (FS) e FS pré-aquecido (FSH). O teste de espessura de película (EP) (n = 10) foi feito usando duas placas de vidro sob compressão. A resistência à flexão (RF) e o módulo flexural (MF) foram avaliados por meio do teste de flexão de três pontos (n = 10). A tensão de contração de polimerização (TCP) foi avaliada em uma máquina de teste universal (n = 8). A largura da fenda (LF) entre o compósito e o molde foi medida em moldes metálicos polidos internamente (n = 10). O grau de conversão (GC) foi avaliado por espectroscopia de infravermelho com transformada de Fourier (n = 3). A morfologia das partículas de carga foi observada em microscopia eletrônica de varredura (MEV) e sua composição em EDX. Brilho superficial (BS) e rugosidade superficial (RS) foram avaliados antes e após escovação mecânica (n=10). Os resultados foram submetidos à ANOVA 2-fatores e as médias comparadas pelo teste de Tukey (α = 0,05). Menores valores médios de EP foram observados para os grupos pré-aquecidos quando comparados aos grupos não pré-aquecidos. URH e FSH apresentaram maiores valores médios de RF e MF quando comparados com UR e FS. Não foram observadas diferenças entre os grupos no teste TCP. A LF foi maior para os grupos UR e FS quando comparados com URH e FSH. O GC foi maior para os compósitos pré-aquecidos quando comparados aos não pré-aquecidos. A RS do compósito UR foi maior que o FS após a escovação mecânica, enquanto o BS foi maior para os grupos FS. Em conclusão, o compósito universal testado geralmente apresentou propriedades físico-químicas semelhantes em comparação ao compósito nanoparticulado e propriedades de superfície semelhantes ou ligeiramente inferiores. O pré-aquecimento melhorou ou manteve todas as propriedades avaliadas.

17.
CienciaUAT ; 17(2): 24-36, ene.-jun. 2023. tab, graf
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1447821

RESUMEN

RESUMEN Existe un interés global en la detección de gases tóxicos, para la protección del medio ambiente y los seres humanos. Se han desarrollado múltiples estudios enfocados en el uso de sensores de gases basados en óxidos metálicos, como es el óxido de zinc (ZnO), el cual presenta propiedades electrónicas específicas como sensor de gases por ser un semiconductor tipo n y bajo costo de producción. El objetivo de este trabajo fue analizar el uso de nanoestructuras de ZnO, para la fabricación de sensores del gas ácido sulfhídrico (H2S), así como las técnicas de obtención más comunes de dichas estructuras. Las características de las nanoestructuras de óxido de zinc (NE´s-ZnO) varían por efecto del método de obtención, generando diferentes morfologías y tamaño, que impactan en la capacidad de detección de gas (0.5 ppm a 600 ppm) y en el rango de temperatura que se requiere. Los avances en la generación de diversas NE´s-ZnO facilitarán la posibilidad de generar sensores que puedan ser utilizados en detectores portátiles y operen a temperatura ambiente, lo cual es un reto actual.


ABSTRACT There is a global interest in the detection of toxic gases for the protection of the environment and human beings, using low-cost and easy-to-use sensors. Multiple studies have focused on the use of gas detectors based on metal oxides, such as zinc oxide (ZnO), which has specific electronic properties as a gas detector because it is an n-type semiconductor and it has a low production cost. The objective of this work was to analyze the use of ZnO nanostructures for the manufacturing of hydrogen sulfide (H2S) gas sensors, as well as the most common techniques for obtaining these structures. The characteristics of zinc oxide nanostructures (NE´s-ZnO) vary due to the effect of the obtaining method, generating different morphologies and sizes, which impacts gas detection performance (0.5 ppm up to 600 ppm) and in the temperature range that is required. Advances in the design of various NE's-ZnO will have the possibility of generating sensors that can be used in portable detectors and operate at room temperature, which is a current challenge.

18.
Artículo | IMSEAR | ID: sea-218948

RESUMEN

The field of nanotechnology is quickly developing and emerging since it has enormous potential for various human uses. With their unique, size-based physical and chemical attributes, nonmaterials generated and engineered through nanotechnology have many applications in biomedicine and agriculture. Theranostics is a branch of nanomedicine that uses small, highly surface-area nanoparticles to diagnose and treat diseases. Nanomaterials have a wide range of uses in agriculture, from fertilizers that improve soil nutrient uptake by plants to nano pesticides that control a variety of pests, including fungi, phytophagous insects, and weeds, increasing food output. Agriculture and food security are intimately connected, and many researchers are interested. Agriculture production depends on many difficulties due to the severe effects of climate change, water problems and changing the distribution of insect pests. Meanwhile, it faces tremendous challenges in maintaining food security for a massive population amid declining resources. Research is actively exploring the use of nonmaterial in agriculture due to their tremendous promise. Despite their good qualities, nonmaterial present risks to the environment and human health, necessitating risk assessment studies. Green nonmaterial synthesis may lessen the usage of toxic agrochemicals that pollute the environment and enter biological systems, providing an environmentally safe, environmentally friendly, and economically advantageous option. In this critical evaluation, nanoparticles are used in agriculture.

19.
Homeopatia Méx ; (n.esp): 68-74, feb. 2023.
Artículo en Español | HomeoIndex, LILACS | ID: biblio-1416727

RESUMEN

La investigación fundamental en homeopatía ha avanzado considerablemente en los últimos 20 años: desde estudios exploratorios con animales y plantas hasta la caracterización de los efectos sistémicos de los medicamentos homeopáticos y estudios in vitro con sistemas celulares aislados para evaluar los cambios en los mecanismos de adaptación celular y señalización intracelular frente a tratamientos homeopáticos variables. El número de artículos publicados a lo largo del tiempo ha permitido realizar varias revisiones sistemáticas. Recientemente, la demostración de que los medicamentos homeopáticos podrían modificar las funciones celulares a través de mecanismos epigenéticos (metilación y desmetilación de ADN) preparó el camino para un campo de investigación completamente nuevo. En paralelo, el descubrimiento de las nanopartículas y propiedades físicas específicas de las diluciones homeopáticas ha arrojado luz hacia un campo antes poco conocido, dado que se consideraba que las diluciones homeopáticas no consistían más que de agua. Así las cosas, los retos para el futuro conciernen a la demostración, o no, de la interrelación entre ambos fenómenos.


Fundamental research in homeopathy has much advanced in the past 20 years. From exploratory studies with animals and plants to the characterization of the systemic effects of homeopathic medicines and in vitro studies with isolated cell systems to assess changes in the mechanisms of cell adaptation and intracellular signaling facing variable homeopathic treatments. The amount of articles published over time enabled several systematic reviews. Recently, demonstration that homeopathic medicines might modify cell functions through epigenetic mechanisms (DNA methylation and demethylation) paved the road for a fully new field of research. In parallel, the discovery of nanoparticles and specific physical properties of homeopathic dilutions brought light to a previously poorly known field, as it was believed that homeopathic dilutions consist in nothing but water. Thus being, challenges for the future concern the demonstration, or not, of the interrelationship between both phenomena.


Asunto(s)
Dinamización , Nanopartículas , Epigenómica
20.
Rev. bras. med. esporte ; 29: e2022_0412, 2023. graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1423333

RESUMEN

ABSTRACT Introduction: Attention is given to developing electrochemical sensors for the rapid and real-time measurement of lactate levels. The synthesis of electrochemical sensors is based on an electrode modified with a nanocomposite. Objective: Analyze an electrochemical sensor's feasibility for sports monitoring sweat in lactate. The Au@CNTs were the main focus of this study. Methods: The Au@CNTs composite was synthesized on the GCE surface and tested under pre-established protocols as a sensor. Results: The shape and structure of the modified electrodes were analyzed using SEM. The results showed that the Au@CNTs nanoparticles in the Au@CNTs nanocomposite were evenly distributed throughout the porous CNTs network. The performance of the developed sensor was measured using cyclic voltammetry and amperometry. The electrochemical biosensor responded linearly to lactate over phosphate buffer solution with a low detection limit and sensitivity. Conclusion: The experiment of this sensor evaluated lactate concentrations in real sweat samples that were exceptionally close to the injection amount, enabling it as an effective biosensor for the detection of lactate in sweat samples. Level of Evidence: Therapeutic Studies - Outcome Investigation.


RESUMO Introdução: É dada atenção ao desenvolvimento de sensores eletroquímicos para a medição rápida e em tempo real dos níveis de lactato. A síntese de sensores eletroquímicos é baseada em um eletrodo modificado com um nanocomposto. Objetivo: Analisar a viabilidade de um sensor eletroquímico para monitoramento esportivo de suor em lactato. O Au@CNTs foi o foco principal deste estudo. Métodos: O composto Au@CNTs foi sintetizado na superfície GCE, e testado sob protocolos preestabelecidos como sensor. Resultados: A forma e estrutura dos eletrodos modificados foram analisadas usando SEM, e os resultados mostraram que as nanopartículas de Au@CNTs no nanocomposto Au@CNTs foram distribuídas uniformemente por toda a rede porosa de CNTs. O desempenho do sensor desenvolvido foi medido usando voltametria cíclica e amperometria. O biosensor eletroquímico respondeu linearmente ao lactato sobre solução tampão fosfato com um limite de detecção e sensibilidade reduzidos. Conclusão: O experimento deste sensor avaliou as concentrações de lactato em amostras de suor real que estavam excepcionalmente próximas à quantidade de injeção, habilitando-o como um biosensor efetivo para detecção de lactato em amostras de suor. Nível de evidência: Estudos Terapêuticos - Investigação dos Resultados.


RESUMEN Introducción: Se presta atención al desarrollo de sensores electroquímicos para la medición rápida y en tiempo real de los niveles de lactato. La síntesis de los sensores electroquímicos se basa en un electrodo modificado con un nanocompuesto. Objetivo: Analizar la viabilidad de un sensor electroquímico para la monitorización esporádica del sudor en el lactato. Los Au@CNTs fueron el objetivo principal de este estudio. Métodos: El compuesto de Au@CNTs se sintetizó sobre la superficie de GCE, y se probó bajo protocolos preestablecidos como sensor. Resultados: La forma y la estructura de los electrodos modificados se analizaron mediante SEM, y los resultados mostraron que las nanopartículas de Au@CNTs en el nanocompuesto de Au@CNTs estaban distribuidas uniformemente en la red porosa de CNTs. El rendimiento del sensor desarrollado se midió mediante voltamperometría cíclica y amperometría. El biosensor electroquímico respondió linealmente al lactato sobre la solución tampón de fosfato con un bajo límite de detección y sensibilidad. Conclusión: El experimento de este sensor evaluó las concentraciones de lactato en muestras reales de sudor que eran excepcionalmente cercanas a la cantidad inyectada, lo que le permite ser un biosensor eficaz para la detección de lactato en muestras de sudor. Nivel de evidencia: Estudios terapéuticos - Investigación de resultados.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA