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1.
Braz. j. biol ; 84: e257070, 2024. tab, ilus
Article in English | LILACS-Express | LILACS, VETINDEX | ID: biblio-1360228

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.


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.

2.
Braz. j. biol ; 84: e253183, 2024. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1355858

ABSTRACT

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.


Subject(s)
Animals , Rats , Magnetite Nanoparticles , Liver Neoplasms , Ferric Compounds , Folic Acid
3.
Methods Mol Biol ; 2566: 321-332, 2023.
Article in English | MEDLINE | ID: mdl-36152263

ABSTRACT

Iron deposits in cells and tissues can be detected by ex vivo histological examination through the Prussian blue (PB) staining. This practical, inexpensive, and highly sensitive technique involves the treatment of fixed tissue sections and cells with acid solutions of ferrocyanides that combine with ferric ion forming a bright blue pigment (i.e., ferric ferrocyanide). The staining can be applied to visualize iron oxide nanoparticles (IONPs), versatile magnetic nanosystems that are used in various biomedical applications and whose localization is usually required at a higher resolution than that enabled by in vivo tracking techniques.

4.
Food Chem ; 400: 133873, 2023 Jan 30.
Article in English | MEDLINE | ID: mdl-36087477

ABSTRACT

To overcome the low production efficiency of Pickering emulsion stabilizers prepared from starch, alcohol precipitation and surface modification were applied in this study. Spherical starch nanoparticles (StNPs) (247.90 ± 1.96 nm) were prepared through nanoprecipitation. The StNPs were surface-esterified to produce starch nanoparticle acetate (StNPAc), and the physicochemical changes of the products were investigated. The contact angle (>89.56° ± 0.56°) of StNPAc (degree of substitution, 0.53) was maintained for over 30 min. The results showed that the hydrophobicity of the StNPs was improved by shielding the surface hydroxyl groups via acetylation. StNPAc was also used to produce emulsions for further evaluation of their feasibility as Pickering emulsifiers. Oil-in-water (3:7, v/v) emulsions containing 1.5 wt% StNPAc were stabilized for over 35 days without creaming. Thus, StNPAc exhibited better emulsifying capacity and storage stability than StNPs. Therefore, hydrophobic starch nanoparticles obtained by acetylation are promising stabilizers for surfactant-free Pickering emulsions.


Subject(s)
Nanoparticles , Starch , Acetates , Emulsions/chemistry , Excipients , Nanoparticles/chemistry , Particle Size , Starch/chemistry , Water/chemistry
5.
Braz. j. biol ; 83: e244675, 2023. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1339348

ABSTRACT

Abstract Several species of thymus have therapeutic properties, so they are used in traditional medicine. In this work was carried out to synthesize Thymus vulgalis silver nanoparticles (TSNPS) and evaluate antioxidant and antimicrobial activities of TSNPS and T. vulgalis essential oil extract (TEOE). The essential oils analyzed by GC-MS and were characterized. Major compounds of phenol, 2 methyl 5 (1 methylethyle) (CAS), thymol and 1,2 Benzene dicarboxylic acid, 3 nitro (CAS) (48.75%, 32.42% and 8.12%, respectively) were detected. Results demonstrated that the TSNPS gave a highest DPPH radical scavenging activity, it was obtained 97.2 at 1000 ug/ml. TSNPS, Thymus + Hexane (T+H), Thymus + Ethanol (T+E) gave the greatest antimicrobial activity than amoxicillin (AM) and ciprofloxacin (CIP). In conclusion: The essential oil of thymus (Vulgaris) and thymus (Vulgaris) silver nanoparticles can be a good source of natural preservatives as an antioxidant and antimicrobial agents for increasing the shelf life of foodstuffs.


Resumo Diversas espécies de timo possuem propriedades terapêuticas, por isso são utilizadas na medicina tradicional. Neste trabalho foi realizado para sintetizar nanopartículas de prata Thymus vulgalis (TSNPS) e avaliar as atividades antioxidante e antimicrobiana de TSNPS e extrato de óleo essencial de T. vulgalis (TEOE). Os óleos essenciais analisados por GC-MS e foram caracterizados. Os principais compostos de fenol, 2 metil 5 (1 metiletilo) (CAS), timol e ácido 1,2 Benzenodicarboxílico, 3 nitro (CAS) (48,75%, 32,42% e 8,12%, respectivamente) foram detectados. Os resultados demonstraram que o TSNPS deu uma maior atividade de eliminação do radical DPPH , foi obtido 97,2 a 1000 ug / ml. TSNPS, Timo + Hexano (T + H), Timo + Etanol (T + E) deu a maior atividade antimicrobiana do que amoxicilina (AM) e ciprofloxacina (CIP). Em conclusão: O óleo essencial de nanopartículas de prata do timo (Vulgaris) e do timo (Vulgaris) pode ser uma boa fonte de conservantes naturais como agentes antioxidantes e antimicrobianos para aumentar a vida útil de alimentos.


Subject(s)
Oils, Volatile/pharmacology , Thymus Plant , Metal Nanoparticles , Anti-Infective Agents/pharmacology , Silver , Antioxidants/pharmacology
6.
Food Chem ; 398: 133851, 2023 Jan 01.
Article in English | MEDLINE | ID: mdl-35963217

ABSTRACT

Modulating the size and surface charge of nanocarriers provides an efficacious strategy to enhance bioavailability of encapsulated cargos through increased mucus penetration. In this study, mucus-permHeable soy protein nanoparticles (SPNPs) were successfully fabricated via gastrointestinal proteolysis coupled with heating and pH-shifting treatment. Results showed that treatment at 65 °C and 75 °C after proteolysis induced the assembly of α, ά, and ß subunits, forming a relatively loose structure. This facilitated further assembly upon pH-shifting, forming smaller-sized and less electronegative nanoparticles, which showed enhanced mucus permeability. However, treatment at 85 °C and 95 °C promoted stronger hydrophobic interactions and induced disulfide bond cross-linking between B and ß subunits, forming compact macro-aggregates with high ß-sheet structure. These larger-sized aggregates were less influenced by pH-shifting treatment, demonstrating limited mucus diffusion. This study provides a potential alternative to fabricate mucus-permeable nanoparticles, and established a relationship between protein subunit assembly behavior and its mucus permeability.


Subject(s)
Nanoparticles , Soybean Proteins , Drug Carriers/chemistry , Hydrogen-Ion Concentration , Hydrolysis , Mucus/metabolism , Nanoparticles/chemistry , Soybean Proteins/chemistry
7.
Food Chem ; 400: 134007, 2023 Jan 30.
Article in English | MEDLINE | ID: mdl-36055149

ABSTRACT

On-site screening of biotoxins is of great importance for food safety. A new electrochemical-biosensing strategy was constructed for ochratoxin A (OTA) detection by direct using ready-made commercial portable-glucose-meter (PGM). Aptamer against OTA was adopted as the recognition probe and pre-immobilized onto the sensing interface. The complementary biotin-modified probe was further decorated by hybridization. Biotinylated invertase was further introduced onto the sensing system with streptavidin, which also acted as the signal amplification unit. The invertase, which was depended on the amount of OTA, produced the glucose from sucrose in the sensing solution. The glucose could be directly and conveniently measured with PGM. Quantitative analysis of OTA was achieved with a linear range from 0.5 ng/mL to 10 ng/mL and detection limit of 0.45 ng/mL. Of significance, it has been successfully applied for OTA analysis in rice with satisfied recoveries. This unique PGM-based electrochemical platform reveals prospective potential in food safety monitoring.


Subject(s)
Aptamers, Nucleotide , Biosensing Techniques , Ochratoxins , Oryza , Aptamers, Nucleotide/chemistry , Biotin , Electrochemical Techniques , Glucose , Limit of Detection , Ochratoxins/analysis , Streptavidin , Sucrose , beta-Fructofuranosidase
8.
Food Chem ; 400: 133960, 2023 Jan 30.
Article in English | MEDLINE | ID: mdl-36063680

ABSTRACT

A proper understanding of silver (Ag) nanoparticles properties is fundamental for developing new antimicrobial agents. In this study, Ag nanoparticles were obtained by green synthesis methods using natural reducing agents present in extracts of apples, oranges, potatoes, red pepper, white onion, garlic and radish. The antimicrobial properties of respective nanoparticles, expressed as the minimum inhibitory concentration, were assessed against Staphylococcus aureus, Bacillus cereus, Escherichia coli, and Candida krusei. Characterization of Ag nanoparticles was done with the application of transmission electron microscopy, X-ray diffraction and UV-vis spectroscopy. The obtained results led to the conclusions that in each extract (pH from 2.1 to 6.2) were obtained specific particles (size from 9 to 30 ± 2 nm) with different antimicrobial activity. Our study indicates that plant extracts gives the Ag nanoparticles specific properties, yet the best antimicrobial properties show nanoparticles obtained in the presence of potato extract.


Subject(s)
Anti-Infective Agents , Metal Nanoparticles , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Anti-Infective Agents/chemistry , Anti-Infective Agents/pharmacology , Escherichia coli , Green Chemistry Technology/methods , Metal Nanoparticles/chemistry , Microbial Sensitivity Tests , Plant Extracts/chemistry , Plant Extracts/pharmacology , Reducing Agents , Silver/chemistry , Silver/pharmacology , Spectroscopy, Fourier Transform Infrared
9.
Food Chem ; 398: 133910, 2023 Jan 01.
Article in English | MEDLINE | ID: mdl-35973296

ABSTRACT

Riboflavin (Rf), an externally supplied nutrient, is highly photosensitive, and should be protected from sunlight once used in food and pharmaceutical manufacturing. The applications of encapsulated Rf have recently developed due to their therapeutic properties. In this study, the use of green silver nanoparticles (AgNPs) synthesized by Rosa damascena mill L. extract to control the encapsulation efficiency of Rf in potato starch was demonstrated for the first time. Starch/Rf, Starch/AgNPs/Rf and Starch/AgNPs nanocapsules were characterized by Fourier-transform infrared, field emission scanning electron microscopy, differential scanning calorimetry, and brunauer-Emmett-Teller techniques. The obtained results showed that the presence of AgNPs reduces Rf nanocapsules size (from 340 to 327 nm), increases the encapsulation efficiency (21.14 ± 0.62 to 92.52 ± 1.32 %) and improves the thermal stability, antibacterial and antioxidant activities. Moreover, UV-vis spectroscopy demonstrated the stronger association of AgNPs/Rf and AgNPs/Rf/Starch nanocapsules with BSA under physiological conditions.


Subject(s)
Metal Nanoparticles , Nanocapsules , Solanum tuberosum , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Metal Nanoparticles/chemistry , Microbial Sensitivity Tests , Plant Extracts/chemistry , Riboflavin , Silver/chemistry , Spectroscopy, Fourier Transform Infrared , Starch , X-Ray Diffraction
10.
Food Chem ; 399: 133964, 2023 Jan 15.
Article in English | MEDLINE | ID: mdl-36029675

ABSTRACT

We employed dithiothreitol (DTT) to reassemble soy lipophilic protein (LP) and increased its solubility for encapsulating resveratrol (Res); we subsequently added hydroxypropyl methylcellulose (HPMC) to further stabilize Res. Physicochemical characterization, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and spectral analysis revealed that DTT triggered the breakage and reassembly of the disulfide bond. Consequently, the solubility of LP increased from 38.64 % to 71.49 %, and the number of free sulfhydryl groups increased to 7.84 mol·g-1. Furthermore, the encapsulation efficiency and structure of reassembled LP nanoparticles loaded with Res were found to be closely related to the DTT concentration used for induction. When HPMC was added, the LP-Res complex demonstrated spontaneous self-assembly, and the pH and temperature stability of the Res in the nanoparticles improved. An in vitro digestion simulation revealed that the reassembled LP was an efficient carrier for Res delivery. Particularly, HPMC improved the bioavailability and sustained release of Res.


Subject(s)
Dithiothreitol , Hypromellose Derivatives , Nanoparticles , Resveratrol , Soybean Proteins , Excipients , Hypromellose Derivatives/chemistry , Nanoparticles/chemistry , Solubility , Soybean Proteins/chemistry , Soybeans
11.
Food Chem ; 399: 133970, 2023 Jan 15.
Article in English | MEDLINE | ID: mdl-35998499

ABSTRACT

Lateral flow immunoassays (LFIAs) are routine methods for rapid foodborne pollutants screening, with detection limits that are closely associated with the label probes used. The exploitation of high performance and robust probe is highly desirable, and remains a great challenge. Herein, we reported an emerging fluorescent nanobeads i.e. carbon-dots (CD) covalently incorporated mesoporous silicon nanoparticles (CD-MSNs) for LFIAs. CD-MSNs revealed brighter fluorescence, larger particle size and more modification sites in comparison with those of single CD. After bio-functionalisation, CD-MSNs probes were introduced to construct LFIA test strips, and designed for ultrasensitive detection of aflatoxin B1 (AFB1) and Staphylococcus aureus (S. aureus), two representative foodborne pollutants, based on the competitive and sandwich models, respectively. Very competitive quantitative detection limits i.e. 0.05 ng/mL and 102 cfu/mL were correspondingly obtained. Additionally, the test strips were successfully applied to rapidly and accurately screen AFB1 and S. aureus in food samples, highlighting their practicality.


Subject(s)
Environmental Pollutants , Nanoparticles , Aflatoxin B1/analysis , Carbon , Fluorescent Dyes , Immunoassay/methods , Limit of Detection , Silicon , Staphylococcus aureus
12.
Food Chem ; 399: 134008, 2023 Jan 15.
Article in English | MEDLINE | ID: mdl-36037693

ABSTRACT

The Tyndall Effect assay (TEA) has been applied into colorimetric metal ion detection since 2019. However, the TEA-based sensor for pesticide detection has never been reported till now. Herein, a facile fluorescent organic nanoparticle (FON)-based sensor is firstly developed for fluorine-containing pesticide detection through ratiometric fluorescence assay (FLA) and TEA. For FLA, the intensity of the second-order Tyndall scattering peak (STS590nm) and the fluorescence peak of the FON-based sensor would increase and remain unchanged respectively when adding bifenthrin, flufenoxuron, and diflubenzuron. The detection limits were respectively 9.34, 6.91, and 3.60 µg/kg. For TEA, the increased STS590nm intensity displayed a bright and visible light beam. An economical, simple, and portable device was then constructed to visually monitor the analytes. The sensor was successfully used to detect the analytes in teas through FLA and TEA with the recoveries and RSD ranging from 86.27-100.00 %, and 0.00-5.68 %, respectively.


Subject(s)
Diflubenzuron , Nanoparticles , Pesticides , Fluorescent Dyes , Fluorides , Fluorine , Phenylurea Compounds , Pyrethrins , Tea
13.
Food Chem ; 399: 133955, 2023 Jan 15.
Article in English | MEDLINE | ID: mdl-36041336

ABSTRACT

Herbicides atrazine and acetochlor are used in crop production. Because of environmental and health hazards with respective maximum contamination levels of 3 and 20 ng/mL, quantifying these herbicides is important when considering presence in foods and vegetables. We utilized two Pd@Pt nanoparticle-amplified immunoassays, a colorimetric Pd@Pt nanoparticle-linked immunosorbent assay (NLISA) and differential pulse voltammetry (DPV) dependent on catalytic activity of Pd@Pt in a dual-lateral flow immunoassay (dual-LFIA-DPV). We achieved overall recoveries of 88.5-114 % in juice, fruit, and vegetable samples for both immunoassays. The NLISA yielded limits of detection (LODs) of 0.59 and 0.31 µg/kg and the dual-LFIA-DPV 0.27 and 0.51 µg/kg for the two respective species. Results for both immunoassays were validated by high-performance liquid chromatography (HPLC), for all food and drink samples though LODs are compromised when configuring the HPLC for both species with the same chromatogram. We expect Pd@Pt-based immunoassays to prove useful in various fields.


Subject(s)
Herbicides , Nanoparticles , Fruit/chemistry , Herbicides/analysis , Immunoassay/methods , Immunosorbents/analysis , Limit of Detection , Vegetables/chemistry
14.
Bioact Mater ; 19: 444-457, 2023 Jan.
Article in English | MEDLINE | ID: mdl-35574050

ABSTRACT

Mesenchymal stem cells (MSCs) therapy shows the potential benefits to relieve clinical symptoms of osteoarthritis (OA), but it is uncertain if it can repair articular cartilage lesions - the main pathology of OA. Here, we prepared biomimetic cupper sulfide@phosphatidylcholine (CuS@PC) nanoparticles (NPs) loaded with plasmid DNA (pDNA) encoding transforming growth factor-beta 1 (TGF-ß1) to engineer MSCs for enhanced OA therapy via cartilage regeneration. We found that the NPs not only promoted cell proliferation and migration, but also presented a higher pDNA transfection efficiency relative to commercial transfection reagent lipofectamine 3000. The resultant CuS/TGF-ß1@PC NP-engineered MSCs (termed CTP-MSCs) were better than pure MSCs in terms of chondrogenic gene expression, glycosaminoglycan deposition and type II collagen formation, favoring cartilage repair. Further, CTP-MSCs inhibited extracellular matrix degradation in interleukin-1ß-induced chondrocytes. Consequently, intraarticular administration of CTP-MSCs significantly enhanced the repair of damaged cartilage, whereas pure MSCs exhibited very limited effects on cartilage regeneration in destabilization of the medial meniscus (DMM) surgical instability mice. Hence, this work provides a new strategy to overcome the limitation of current stem cell therapy in OA treatment through developing more effective nanoengineered MSCs.

15.
Bioact Mater ; 19: 418-428, 2023 Jan.
Article in English | MEDLINE | ID: mdl-35574059

ABSTRACT

Labeling of mesenchymal stem cells (MSCs) with superparamagnetic iron oxide nanoparticles (SPIONs) has emerged as a potential method for magnetic resonance imaging (MRI) tracking of transplanted cells in tissue repair studies and clinical trials. Labeling of MSCs using clinically approved SPIONs (ferumoxytol) requires the use of transfection reagents or magnetic field, which largely limits their clinical application. To overcome this obstacle, we established a novel and highly effective method for magnetic labeling of MSC spheroids using ferumoxytol. Unlike conventional methods, ferumoxytol labeling was done in the formation of a mechanically tunable biomimetic hydrogel-induced MSC spheroids. Moreover, the labeled MSC spheroids exhibited strong MRI T2 signals and good biosafety. Strikingly, the encapsulated ferumoxytol was localized in the extracellular matrix (ECM) of the spheroids instead of the cytoplasm, minimizing the cytotoxicity of ferumoxytol and maintaining the viability and stemness properties of biomimetic hydrogel-induced MSC spheroids. This demonstrates the potential of this method for post-transplantation MRI tracking in the clinic.

16.
Environ Pollut ; 302: 119062, 2022 Jun 01.
Article in English | MEDLINE | ID: mdl-35231537

ABSTRACT

Lead is a metal that exists naturally in the Earth's crust and is a ubiquitous environmental contaminant. The alleviation of lead toxicity is important to keep human health under lead exposure. Biosynthesized selenium nanoparticle (SeNPs) and selenium-enriched Lactobacillus rhamnosus SHA113 (Se-LRS) were developed in this study, and their potentials in alleviating lead-induced injury to the liver and intestinal tract were evaluated in mice by oral administration for 4 weeks. As results, oral intake of lead acetate (150 mg/kg body weight per day) caused more than 50 times and 100 times lead accumulation in blood and the liver, respectively. Liver function was seriously damaged by the lead exposure, which is indicated as the significantly increased lipid accumulation in the liver, enhanced markers of liver function injury in serum, and occurrence of oxidative stress in liver tissues. Serious injury in intestinal tract was also found under lead exposure, as shown by the decrease of intestinal microbiota diversity and occurrence of oxidative stress. Except the lead content in blood and the liver were lowered by 52% and 58%, respectively, oral administration of Se-LRS protected all the other lead-induced injury markers to the normal level. By the comparison with the effects of normal L. rhamnosus SHA113 and the SeNPs isolated from Se-LRS, high protective effects of Se-LRS can be explained as the extremely high efficiency to promote lead excretion via feces by forming insoluble mixture. These findings illustrate the developed selenium-enriched L. rhamnosus can efficiently protect the liver and intestinal tract from injury by lead.


Subject(s)
Intestinal Diseases , Lactobacillus rhamnosus , Selenium , Animals , Lead/toxicity , Liver , Mice , Selenium/pharmacology
17.
Nanotechnology ; 33(23)2022 Mar 15.
Article in English | MEDLINE | ID: mdl-35193121

ABSTRACT

We combined phosphoinositol-3-kinin inhibitor IPI-549 and photodynamic Chlorin e6 (Ce6) on carboxymethyl chitosan to develop a novel drug delivery nanoparticle (NP) system (Ce6/CMCS-DSP-IPI549) and evaluate its glutathione (GSH) sensitivity and targeting ability for breast cancer treatment. The NPs were spherical with a uniform size of 218.8 nm, a stable structure over 7 days. The maximum encapsulation efficiency was 64.42%, and NPs drug loading was 8.05%. The NPs released drugs within tumor cells due to their high GSH concentration, while they maintained structural integrity in normal cells, which have low GSH concentration. The cumulative release rates of IPI-549 and Ce6 at 108 h were 70.67% and 40.35% (at GSH 10 mM) and 8.11% and 2.71% (at GSH 2µM), respectively. The NPs showed a strong inhibitory effect on 4T1 cells yet did not affect human umbilical vein endothelial cells (HUVECs). After irradiation by a 660 nm infrared laser for 72 h, the survival rate of 4T1 cells was 15.51%. Cellular uptake studies indicated that the NPs could accurately release drugs into tumor cells. In addition, the NPs had a good photodynamic effect and promoted the release of reactive oxygen species to damage tumor cells. Overall, the combination therapy of IPI-549 and Ce6 is safe and effective, and may provide a new avenue for the treatment of breast cancer.


Subject(s)
Breast Neoplasms , Chlorophyllides , Nanoparticles , Photochemotherapy , Porphyrins , Breast Neoplasms/drug therapy , Breast Neoplasms/pathology , Cell Line, Tumor , Chlorophyllides/therapeutic use , Endothelial Cells/pathology , Female , Glutathione , Humans , Isoquinolines , Nanoparticles/chemistry , Photosensitizing Agents , Porphyrins/chemistry , Pyrazoles , Pyrimidines
18.
Rev. biol. trop ; 70(1)dic. 2022.
Article in English | LILACS-Express | LILACS, SaludCR | ID: biblio-1387704

ABSTRACT

Abstract Introduction: Pathogenic protozoans, like Entamoeba histolytica and Trichomonas vaginalis, represent a major health problem in tropical countries; and polymeric nanoparticles could be used to apply plant extracts against those parasites. Objective: To test Curcuma longa ethanolic extract and Berberis vulgaris methanolic extracts, and their main constituents, against two species of protozoans. Methods: We tested the extracts, as well as their main constituents, curcumin (Cur) and berberine (Ber), both non-encapsulated and encapsulated in polymeric nanoparticles (NPs), in vitro. We also determined nanoparticle characteristics by photon correlation spectroscopy and scanning electron microscopy, and hemolytic capacity by hemolysis in healthy erythrocytes. Results: C. longa consisted mainly of tannins, phenols, and flavonoids; and B. vulgaris in alkaloids. Encapsulated particles were more effective (P < 0.001); however, curcumin and berberine nanoparticles were the most effective treatments. CurNPs had IC50 values (µg/mL) of 9.48 and 4.25, against E. histolytica and T. vaginalis, respectively, and BerNPs 0.24 and 0.71. The particle size and encapsulation percentage for CurNPs and BerNPs were 66.5 and 73.4 nm, and 83.59 and 76.48 %, respectively. The NPs were spherical and significantly reduced hemolysis when compared to non-encapsulated extracts. Conclusions: NPs represent a useful and novel bioactive compound delivery system for therapy in diseases caused by protozoans.


Resumen Introducción: Los protozoos patógenos, como Entamoeba histolytica y Trichomonas vaginalis, representan un importante problema de salud en los países tropicales; y se podrían usar nanopartículas poliméricas para aplicar extractos de plantas contra esos parásitos. Objetivo: Probar los extractos etanólicos de Curcuma longa y Berberis vulgaris, y sus principales constituyentes, contra dos especies de protozoos. Métodos: Probamos los extractos, así como sus principales constituyentes, curcumina (Cur) y berberina (Ber), tanto no encapsulados como encapsulados en nanopartículas poliméricas (NPs), in vitro. También determinamos las características de las nanopartículas por espectroscopía de correlación de fotones y microscopía electrónica de barrido, y la capacidad hemolítica por hemólisis en eritrocitos sanos. Resultados: C. longa tenía principalmente: taninos, fenoles y flavonoides; y B. vulgaris, alcaloides. Las partículas encapsuladas fueron más efectivas (P < 0.001); sin embargo, las nanopartículas de curcumina y berberina fueron los tratamientos más efectivos. CurNPs tenía valores IC50 (µg/mL) de 9.48 y 4.25, contra E. histolytica y T. vaginalis, respectivamente, y BerNPs 0.24 y 0.71. El tamaño de partícula y el porcentaje de encapsulación para CurNPs y BerNPs fueron: 66.5 y 73.4 nm, y 83.59 y 76.48 %, respectivamente. Los NP son esféricos y redujeron significativamente la hemólisis en comparación con los extractos no encapsulados. Conclusiones: Las NP representan un sistema de administración de compuestos bioactivos útil y novedoso para la terapia enfermedades causadas por protozoos.


Subject(s)
Trichomonas vaginalis , Berberis vulgaris , Curcuma , Entamoeba histolytica
19.
Mikrochim Acta ; 189(10): 385, 2022 09 20.
Article in English | MEDLINE | ID: mdl-36125554

ABSTRACT

Cobalt hydroxide nanoparticles (Co(OH)2 NPs) were uniformly deposited on flexible carbon cloth substrate (Co(OH)2@CC) rapidly by a facile one-step electrodeposition, which can act as an enzyme-free glucose and uric acid sensor in an alkaline electrolyte. Compositional and morphological characterization were examined by X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDS), which confirmed the deposited nanospheres were Co(OH)2 nanoparticles (NPs). The electrochemical oxidation of glucose and uric acid at Co(OH)2@CC electrode was investigated by electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), differential pulse voltammetry (DPV), and chronoamperometry methods. The results revealed a remarkable electrocatalytic activity toward the single and simultaneous determination of glucose and uric acid at about 0.6 V and 0.3 V (vs. Ag/AgCl), respectively, which is attributed to a noticeable synergy effect between Co(OH)2 NPs and CC with good repeatability, satisfactory reproducibility, considerable long-term stability, superior selectivity, outstanding sensitivity, and wide linear detection range from 1 uM to 2 mM and 25 nM to 1.5 uM for glucose and UA, respectively. The detection limits were 0.36 nM for UA and 0.24 µM for glucose (S/N = 3). Finally, the Co(OH)2@CC electrode was utilized for glucose and uric acid determination in human blood samples and satisfying results were obtained. The relative standard derivations (RSDs) for glucose and UA were in the range 6 to 14% and 0 to 3%, respectively. The recovery ranges for glucose an UA were 97 to 103% and 95 and 101%, respectively. These features make the novel Co(OH)2@CC sensor developed by a low-cost, efficient, and eco-friendly preparation method a potentially practical candidate for application to biosensors.


Subject(s)
Carbon , Nanoparticles , Carbon/chemistry , Electrochemical Techniques/methods , Glucose , Humans , Nanoparticles/chemistry , Reproducibility of Results , Uric Acid
20.
J Pharm Sci ; 2022 Sep 18.
Article in English | MEDLINE | ID: mdl-36130677

ABSTRACT

At the outset of the coronavirus disease 2019 (COVID-19) pandemic, it was clear that a vaccine would be crucial for global health efforts. The Pfizer and BioNTech teams came together in a race against the virus, working to design, test, manufacture, and distribute a safe and efficacious vaccine in record time for people around the world. Here, we provide backstory commentary from the pharmaceutical scientist perspective on the challenges and solutions encountered in the development of the Pfizer-BioNTech mRNA COVID-19 vaccine (BNT162b2; b2; Comirnaty®; tozinameran). We discuss the foundational science that led to the decision to use an mRNA-based approach. We also describe key challenges in the identification of an optimal vaccine candidate and testing in clinical trials, the continuous efforts to improve the vaccine formulation in response to changing global health priorities and facilitate vaccine accessibility, and how vast quantities of vaccine doses were manufactured and safely delivered to every corner of the globe, all without compromising quality, science, and safety. The key to successfully delivering a safe and efficacious vaccine within nine months was a result of extraordinary, real-time, parallel effort and across-the-board collaboration between stakeholders on a global scale.

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