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1.
Molecules ; 29(9)2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38731398

RESUMO

(1) Background: Alzheimer's disease (AD) is characterized by ß-amyloid (Aß) peptide accumulation and mitochondrial dysfunction during the early stage of disease. PINK1 regulates the balance between mitochondrial homeostasis and bioenergy supply and demand via the PINK1/Parkin pathway, Na+/Ca2+ exchange, and other pathways. (2) Methods: In this study, we synthesized positively charged carbon dots (CA-PEI CDs) using citric acid (CA) and polyethyleneimine (PEI) and used them as vectors to express PINK1 genes in the APP/PS1-N2a cell line to determine mitochondrial function, electron transport chain (ETC) activity, and ATP-related metabolomics. (3) Results: Our findings showed that the CA-PEI CDs exhibit the characteristics of photoluminescence, low toxicity, and concentrated DNA. They are ideal biological carriers for gene delivery. PINK1 overexpression significantly increased the mitochondrial membrane potential in APP/PS1-N2a cells and reduced reactive-oxygen-species generation and Aß1-40 and Aß1-42 levels. An increase in the activity of NADH ubiquinone oxidoreductase (complex I, CI) and cytochrome C oxidase (complex IV, CIV) induces the oxidative phosphorylation of mitochondria, increasing ATP generation. (4) Conclusions: These findings indicate that the PINK gene can alleviate AD by increasing bioenergetic metabolism, reducing Aß1-40 and Aß1-42, and increasing ATP production.


Assuntos
Trifosfato de Adenosina , Carbono , Ácido Cítrico , Mitocôndrias , Polietilenoimina , Proteínas Quinases , Polietilenoimina/química , Carbono/química , Trifosfato de Adenosina/metabolismo , Proteínas Quinases/metabolismo , Proteínas Quinases/genética , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Camundongos , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Pontos Quânticos/química , Animais , Peptídeos beta-Amiloides/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Humanos , Linhagem Celular , Espécies Reativas de Oxigênio/metabolismo , Presenilina-1/genética , Presenilina-1/metabolismo
2.
Molecules ; 29(9)2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38731508

RESUMO

This study delves into the physicochemical properties of inorganic hydroxyapatite (HAp) and hybrid hydroxyapatite-chitosan (HAp-CTS) granules, also gold-enriched, which can be used as aggregates in biomicroconcrete-type materials. The impact of granules' surface modifications with citric acid (CA) or polyethylene glycol (PEG) was assessed. Citric acid modification induced increased specific surface area and porosity in inorganic granules, contrasting with reduced parameters in hybrid granules. PEG modification resulted in a slight increase in specific surface area for inorganic granules and a substantial rise for hybrid granules with gold nanoparticles. Varied effects on open porosity were observed based on granule type. Microstructural analysis revealed increased roughness for inorganic granules post CA modification, while hybrid granules exhibited smoother surfaces. Novel biomicroconcretes, based on α-tricalcium phosphate (α-TCP) calcium phosphate cement and developed granules as aggregates within, were evaluated for compressive strength. Compressive strength assessments showcased significant enhancement with PEG modification, emphasizing its positive impact. Citric acid modification demonstrated variable effects, depending on granule composition. The incorporation of gold nanoparticles further enriched the multifaceted approach to enhancing calcium phosphate-based biomaterials for potential biomedical applications. This study demonstrates the pivotal role of surface modifications in tailoring the physicochemical properties of granules, paving the way for advanced biomicroconcretes with improved compressive strength for diverse biomedical applications.


Assuntos
Ácido Cítrico , Durapatita , Polietilenoglicóis , Ácido Cítrico/química , Durapatita/química , Polietilenoglicóis/química , Ouro/química , Materiais Biocompatíveis/química , Teste de Materiais , Quitosana/química , Porosidade , Nanopartículas Metálicas/química , Fenômenos Químicos , Força Compressiva , Propriedades de Superfície
3.
Carbohydr Polym ; 338: 122208, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38763729

RESUMO

This study examines the impact and influence of amylose on the starch esterification reaction through partial extraction of amylose. Citric acid was added for the esterification reaction, and then the esterified starches' multiscale structure, physicochemical, and functional properties were evaluated. As the extraction time of amylose increased, the amylose content in the starch decreased. Higher concentrations of citric acid will lead to samples with a higher degree of substitution, with DS rising from 0.203 % (0 h) to 0.231 % (3.5 h) at CA3 treatment. While removing amylose had minimal effects on the crystal structure of starch granules, it did decrease the ratio of A and B1 chains and the molecular weight of amylose. Acid hydrolysis exacerbated these changes upon the addition of citric acid. Furthermore, removing amylose followed by citrate esterification resulted in lower pasting viscosity, enthalpy of gelatinization (from 13.37 J to 2.83 J), and degree of short-range ordering. Also, digestion shows a decrease caused by the increasing content of slow-digesting starch. The presence of amylose in starch granules does affect the formation of starch esters, and removing it before esterification modification may improve production efficiency and reduce costs to some extent.


Assuntos
Amilose , Ácido Cítrico , Solanum tuberosum , Amido , Amilose/química , Esterificação , Ácido Cítrico/química , Solanum tuberosum/química , Amido/química , Viscosidade , Hidrólise , Peso Molecular
4.
J Colloid Interface Sci ; 668: 678-690, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38710124

RESUMO

Aerogels, as a unique porous material, are expected to be used as insulation materials to solve the global environmental and energy crisis. Using chitosan, citric acid, pectin and phytic acid as raw materials, an all-biomass-based aerogel with high modulus was prepared by the triple strategy of ionic, physical and chemical cross-linking through directional freezing technique. Based on this three-dimensional network, the aerogel exhibited excellent compressive modulus (24.89 ± 1.76 MPa) over a wide temperature range and thermal insulation properties. In the presence of chitosan, citric acid and phytic acid, the aerogel obtained excellent fire safety (LOI value up to 31.2%) and antibacterial properties (antibacterial activity against Staphylococcus aureus and Escherichia coli reached 81.98% and 67.43%). In addition, the modified aerogel exhibited excellent hydrophobicity (hydrophobic angle of 146°) and oil-water separation properties. More importantly, the aerogel exhibited a biodegradation rate of up to 40.31% for 35 days due to its all-biomass nature. This work provides a green and sustainable strategy for the production of highly environmentally friendly thermal insulation materials with high strength, flame retardant, antibacterial and hydrophobic properties.


Assuntos
Antibacterianos , Quitosana , Ácido Cítrico , Escherichia coli , Géis , Staphylococcus aureus , Escherichia coli/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/farmacologia , Antibacterianos/química , Géis/química , Quitosana/química , Ácido Cítrico/química , Biomassa , Interações Hidrofóbicas e Hidrofílicas , Porosidade , Ácido Fítico/química , Pectinas/química , Reagentes de Ligações Cruzadas/química , Testes de Sensibilidade Microbiana , Propriedades de Superfície , Tamanho da Partícula , Temperatura
5.
J Am Chem Soc ; 146(20): 13903-13913, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38721817

RESUMO

Cohesive and interfacial adhesion energies are difficult to balance to obtain reversible adhesives with both high mechanical strength and high adhesion strength, although various methods have been extensively investigated. Here, a biocompatible citric acid/L-(-)-carnitine (CAC)-based ionic liquid was developed as a solvent to prepare tough and high adhesion strength ionogels for reversible engineered and biological adhesives. The prepared ionogels exhibited good mechanical properties, including tensile strength (14.4 MPa), Young's modulus (48.1 MPa), toughness (115.2 MJ m-3), and high adhesion strength on the glass substrate (24.4 MPa). Furthermore, the ionogels can form mechanically matched tough adhesion at the interface of wet biological tissues (interfacial toughness about 191 J m-2) and can be detached by saline solution on demand, thus extending potential applications in various clinical scenarios such as wound adhesion and nondestructive transfer of organs.


Assuntos
Materiais Biocompatíveis , Ácido Cítrico , Géis , Materiais Biocompatíveis/química , Materiais Biocompatíveis/síntese química , Ácido Cítrico/química , Géis/química , Carnitina/química , Líquidos Iônicos/química , Resistência à Tração , Adesivos/química
6.
Am J Dent ; 37(2): 66-70, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38704848

RESUMO

PURPOSE: To evaluate the effect of different finishing and polishing systems on the surface roughness of a resin composite subjected to simulated saliva-, acid-, and enzyme-induced degradation. METHODS: 160 specimens (n= 40) were fabricated with Filtek Z350 XT nanofilled composite and analyzed for average surface roughness (Ra). The specimens were finished and polished using: AD - Al2O3-impreginated rubberized discs (medium, fine, and superfine grit, Sof-Lex); SD - silicon carbide and Al2O3-impregnated rubberized discs (coarse, medium and fine grit, Jiffy,); MB - 12- and 30-multiblade burs. The control group (CT) (n= 40) comprised specimens with a Mylar-strip-created surface. Specimens from each group were immersed in 1 mL of one of the degradation methods (n= 10): artificial saliva (ArS: pH 6.75), cariogenic challenge (CaC: pH 4.3), erosive challenge (ErC: 0.05M citric acid, pH 2.3) or enzymatic challenge (EzC: artificial saliva with 700 µg/mL of albumin, pH 6.75). The immersion period simulated a time frame of 180 days. Ra measurements were also performed at the post-polishing and post-degradation time points. The data were evaluated by three-way ANOVA for repeated measures and the Tukey tests. RESULTS: There was significant interaction between the finishing/polishing system and the degradation method (P= 0.001). AD presented the greatest smoothness, followed by SD. After degradation, CT, AD and SD groups became significantly rougher, but not the MB group, which presented no difference in roughness before or after degradation. CT and AD groups showed greater roughness in CaC, ErC and EzC than in ArS. The SD group showed no difference in roughness when the specimens were polished with CaC, EzC or ArS, but those treated with ErC had greater roughness. In the MB group, the lower roughness values were found after using CaC and EzC, while the higher values were found using ErC or ArS. CLINICAL SIGNIFICANCE: As far as degradation resistance of nanofilled composite to hydrolysis, bacterial and dietary acids and enzymatic reactions is concerned, restorations that had been finished and polished with Al2O3-impregnated discs had the smoothest surfaces.


Assuntos
Óxido de Alumínio , Resinas Compostas , Polimento Dentário , Saliva Artificial , Compostos de Silício , Propriedades de Superfície , Resinas Compostas/química , Polimento Dentário/métodos , Humanos , Saliva Artificial/química , Concentração de Íons de Hidrogênio , Óxido de Alumínio/química , Compostos de Silício/química , Compostos Inorgânicos de Carbono/química , Teste de Materiais , Nanocompostos/química , Ácido Cítrico/química , Saliva/enzimologia , Saliva/metabolismo , Saliva/química , Erosão Dentária , Borracha/química , Materiais Dentários/química
7.
Sci Rep ; 14(1): 11386, 2024 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-38762573

RESUMO

Aspiration pneumonia is the leading cause of death in patients with Parkinson's disease. The incidence of silent aspiration is high in such patients owing to decreased pharyngeal and laryngeal sensation; thus, interventions for this condition may help prevent pneumonia. In this single-arm, open-label study, we used a cervical percutaneous interferential current stimulation device to activate pharyngeal and laryngeal sensory nerves. We evaluated its effectiveness in patients with Hoehn-Yahr stages 2-4 Parkinson's disease. The primary endpoint was the proportion of patients with a normal cough reflex after consuming 1% citric acid at the end of the intervention compared with baseline measurements. In total, 25 patients received neck percutaneous interferential current stimulation for 20 min twice weekly for 8 weeks. Afterward, the proportion of patients with a normal cough reflex after 1% citric acid consumption increased significantly (p = 0.001), whereas other indicators, such as tongue pressure, peak expiratory flow, and penetration or aspiration during videofluoroscopic examination, remained unchanged. A longer duration of illness, higher Unified Parkinson's Disease Rating Scale total scores, and higher levodopa equivalent daily doses were significantly associated with improved cough test outcomes. Hence, cervical percutaneous interferential current stimulation significantly improved cough reflexes and may improve silent aspiration. Trial Registration: Japan Registry of Clinical Trials, jRCTs062220013, first registered 09/05/2022.


Assuntos
Ácido Cítrico , Tosse , Doença de Parkinson , Humanos , Doença de Parkinson/terapia , Doença de Parkinson/fisiopatologia , Feminino , Masculino , Idoso , Tosse/tratamento farmacológico , Pessoa de Meia-Idade , Pneumonia Aspirativa/etiologia , Pneumonia Aspirativa/prevenção & controle , Terapia por Estimulação Elétrica/métodos
8.
Ren Fail ; 46(1): 2334396, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38570195

RESUMO

OBJECTIVES: Calcium oxalate (CaOx) crystal deposition in acute kidney injury (AKI) patients is under recognized but impacts renal outcomes. This study investigates its determinants and effects. METHODS: We studied 814 AKI patients with native kidney biopsies from 2011 to 2020, identifying CaOx crystal deposition severity (mild: <5, moderate: 5-10, severe: >10 crystals per section). We assessed factors like urinary oxalate, citrate, urate, electrolytes, pH, tubular calcification index, and SLC26A6 expression, comparing them with creatinine-matched AKI controls without oxalosis. We analyzed how these factors relate to CaOx severity and their impact on renal recovery (eGFR < 15 mL/min/1.73 m2 at 3-month follow-up). RESULTS: CaOx crystal deposition was found in 3.9% of the AKI cohort (32 cases), with 72% due to nephrotoxic medication-induced tubulointerstitial nephritis. Diuretic use, higher urinary oxalate-to-citrate ratio induced by hypocitraturia, and tubular calcification index were significant contributors to moderate and/or severe CaOx deposition. Poor baseline renal function, low urinary chloride, high uric acid and urea nitrogen, tubular SLC26A6 overexpression, and glomerular sclerosis were also associated with moderate-to-severe CaOx deposition. Kidney recovery was delayed, with 43.8%, 31.2%, and 18.8% of patients having eGFR < 15 mL/min/1.73 m2 at 4, 12, and 24-week post-injury. Poor outcomes were linked to high urinary α1-microglobulin-to-creatinine (α1-MG/C) ratios and active tubular injury scores. Univariate analysis showed a strong link between this ratio and poor renal outcomes, independent of oxalosis severity. CONCLUSIONS: In AKI, CaOx deposition is common despite declining GFR. Factors worsening tubular injury, not just oxalate-to-citrate ratios, are key to understanding impaired renal recovery.


Assuntos
Injúria Renal Aguda , Calcinose , Hiperoxalúria , Humanos , Oxalato de Cálcio/química , Creatinina/metabolismo , Rim/patologia , Hiperoxalúria/complicações , Oxalatos/metabolismo , Injúria Renal Aguda/patologia , Citratos/metabolismo , Ácido Cítrico
9.
Rapid Commun Mass Spectrom ; 38(11): e9738, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38572671

RESUMO

RATIONALE: Accurate identification of old rice samples from new ones benefits their market circulation and consumers. However, the current detection methods are still not satisfactory because of their insufficient accuracy or (and) time-consuming process. METHODS: Chelating carboxylic acids (CCAs) were selectively extracted from rice, by stirring with chelating resin and a dilute Na2CO3 solution. The green analytical chemistry guidelines for sample preparation were investigated by using the green chemistry calculator AGREE prep. The extractant was determined by liquid chromatography-mass spectrometry (LC/MS), and statistical analysis of the analytical data was carried out to evaluate the significance of the difference by ChiPlot. RESULTS: The limit of quantitation for the CCAs is in the range of 1 to 50 ng/mL, with a reasonable reproducibility. The CCAs in 23 rice samples were determined within a wide concentration range from 0.03 to 1174 µg/g. Intriguingly, the content of citric acid, malonic acid, α-ketoglutaric acid and cis-aconite acid in new rice was each found to be distinctively higher than that in old rice by several times. Even mixtures of old and new rice were found to show much difference in the concentration of citric acid and malic acid. CONCLUSION: A green analytical method has been developed for the simultaneous determination of CCAs by LC/MS analysis, and the identification of old rice samples from new ones was easily carried out according to their CCA content for the first time. The results indicated that the described method has powerful potential for the accurate identification of old rice samples from new ones.


Assuntos
Espectrometria de Massa com Cromatografia Líquida , Oryza , Cromatografia Líquida/métodos , Ácidos Carboxílicos , Oryza/química , Espectrometria de Massas em Tandem/métodos , Reprodutibilidade dos Testes , Ácido Cítrico , Cromatografia Líquida de Alta Pressão/métodos , Extração em Fase Sólida
10.
Huan Jing Ke Xue ; 45(5): 3016-3026, 2024 May 08.
Artigo em Chinês | MEDLINE | ID: mdl-38629562

RESUMO

Sweet sorghum has a large biomass and strong cadmium (Cd) absorption capacity, which has the potential for phytoremediation of Cd-contaminated soil. In order to study the Cd phytoremediation effect of sweet sorghum assisted with citric acid on the typical parent materials in southern China, a field experiment was carried out in two typical parent material farmland areas (neutral purple mud field and jute sand mud field) with Cd pollution in Hunan Province. The results showed that:① Citric acid had no inhibitory effect on the growth of sweet sorghum. After the application of citric acid, the aboveground biomass of sweet sorghum at the maturity stage increased by 10.1%-24.7%. ② Both sweet sorghum planting and citric acid application reduced the soil pH value, and the application of citric acid further reduced the soil pH value at each growth stage of sweet sorghum; this decrease was greater in the neutral purple mud field, which decreased by 0.24-0.72 units. ③ Both sweet sorghum planting and citric acid application reduced the total amount of soil Cd, and the decreases in the neutral purple mud field and jute sand mud field were 23.8%-52.2% and 17.1%-31.8%, respectively. The acid-extractable percentage of soil Cd in both places increased by 38.6%-147.7% and 4.8%-22.7%, respectively. ④ The application of citric acid could significantly increase the Cd content in various tissues of sweet sorghum. The Cd content in the aboveground part of the plant in the neutral purple mud field was higher than that in the jute sand mud field, and the Cd content in stems and leaves was 0.25-1.90 mg·kg-1 and 0.21-0.64 mg·kg-1, respectively. ⑤ After applying citric acid, the Cd extraction amount of sweet sorghum in neutral purple mud soil in the mature stage reached 47.56 g·hm-2. In summary, citric acid could enhance the efficiency of sweet sorghum in the phytoremediation of Cd-contaminated soil, and the effect was better in neutral purple mud fields. This technology has the potential for remediation coupled with agro-production for heavy metal-contaminated farmland.


Assuntos
Poluentes do Solo , Sorghum , Cádmio/análise , Biodegradação Ambiental , Solo , Areia , Ácido Cítrico , Poluentes do Solo/análise , China , Grão Comestível/química
11.
Commun Biol ; 7(1): 443, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38605181

RESUMO

Glutamate is an essential biological compound produced for various therapeutic and nutritional applications. The current glutamate production process requires a large amount of ammonium, which is generated through the energy-consuming and CO2-emitting Haber-Bosch process; therefore, the development of bio-economical glutamate production processes is required. We herein developed a strategy for glutamate production from aerial nitrogen using the nitrogen-fixing bacterium Klebsiella oxytoca. We showed that a simultaneous supply of glucose and citrate as carbon sources enhanced the nitrogenase activity of K. oxytoca. In the presence of glucose and citrate, K. oxytoca strain that was genetically engineered to increase the supply of 2-oxoglutarate, a precursor of glutamate synthesis, produced glutamate extracellularly more than 1 g L-1 from aerial nitrogen. This strategy offers a sustainable and eco-friendly manufacturing process to produce various nitrogen-containing compounds using aerial nitrogen.


Assuntos
Ácido Glutâmico , Klebsiella oxytoca , Klebsiella oxytoca/genética , Nitrogênio , Ácido Cítrico , Engenharia Metabólica , Glucose
12.
Molecules ; 29(7)2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38611930

RESUMO

The ability of ß-CD to form inclusion complexes with ibuprofen (IBU) and at the same time to make a two-phase system with citric acid was explored in the present study for achieving improved solubility and dissolution rate of IBU. Mechanical milling as well as mechanical milling combined with thermal annealing of the powder mixtures were applied as synthetic methods. Solubility and dissolution kinetics of the complexes were studied in compliance with European Pharmacopoeia (ICH Q4B). ß-CD and citric acid (CA) molecules were shown to interact by both ball milling (BM), thermal annealing, as well as BM with subsequent annealing. Complexes were also formed by milling the three compounds (ß-CD, CA and IBU) simultaneously, as well as by a consecutive first including IBU into ß-CD and then binding the formed ß-CD/IBU inclusion complex with CA. As a result, ternary ß-CD/IBU/CA complex formed by initial incorporation of ibuprofen into ß-CD, followed by successive formation of a two-phase mixture with CA, exhibited notably improved dissolution kinetics compared to the pure ibuprofen and slightly better compared to the binary ß-CD/IBU system. Although the addition of CA to ß-CD/IBU does not significantly increase the solubility rate of IBU, it must be considered that the amount of ß-CD is significantly less in the ternary complex compared to the binary ß-CD/IBU.


Assuntos
Ibuprofeno , beta-Ciclodextrinas , Solubilidade , Ácido Cítrico , Cinética
13.
Waste Manag ; 182: 237-249, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38677141

RESUMO

The effectiveness of dehydration and utilization processes for citric acid dewatered sludge is hampered by its high concentrations of polysaccharides, proteins, and water-binding properties of microbial extracellular polymers (EPS). This research explores the efficacy and mechanisms involved in extracting water from this type of sludge using biological drying technology, with varying rates of ventilation. Especially pertinent was the use of low ventilation rates as control variables. Our results suggest that a scheduled intermittent ventilation at lower rates allows for the most efficient removal of water, achieving a rate of 41.71 % within eight days, according to the zero-order kinetic model. Remarkably, the peak temperature registered was 60 °C, reaching this threshold in just 0.1 days and maintaining high temperatures for approximately 5.9 days. Component analysis of organic matter illustrated a preferential degradation process for lipids under these ventilation conditions which is pivotal for releasing and transforming bound water for efficient extraction, as well as facilitating the breakdown of easily hydrolysable materials. Further, polysaccharide/protein (EPS) decomposition contributed to water removal, though less significantly. The periodic ventilation strategy allowed for the maximum cumulative temperature to be sustained, demonstrating superior efficiency in harnessing bio-generated heat (82.77 % for water evaporation), resulting in dry sludge suitable for self-sustained combustion at relatively low cost ($26.61/t). Highlighted by this study is the considerable potential of energy-efficient ventilation methods in the biological drying treatment of citric acid fermented sludge and similar industrial waste materials.


Assuntos
Ácido Cítrico , Dessecação , Esgotos , Dessecação/métodos , Eliminação de Resíduos Líquidos/métodos , Água
14.
Bioresour Technol ; 401: 130719, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38642662

RESUMO

Currently, the production of manno-oligosaccharides (MOS) from guar gum faces challenges of low oligosaccharide enzymatic hydrolysis yield and complicated steps in separation and purification. In this work, a potential strategy to address these issues was explored. By combining citric acid pretreatment (300 mM, 130 °C, 1 h) with ß-mannanase hydrolysis, an impressive MOS yield of 61.8 % from guar gum (10 %, w/v) was achieved. The key success lay in the optimizing conditions that completely degraded other galactomannans into monosaccharides, which could be easily removable through Saccharomyces cerevisiae fermentation (without additional nutrients). Following ion exchange chromatography for desalination, and concluding with spray drying, 4.57 g of solid MOS with a purity of 90 % was obtained from 10 g of guar gum. This method offers a streamlined and effective pathway for obtaining high-yield and high-purity MOS from guar gum by combining citric acid pretreatment and enzymatic hydrolysis.


Assuntos
Ácido Cítrico , Galactanos , Mananas , Oligossacarídeos , Gomas Vegetais , beta-Manosidase , Mananas/química , Gomas Vegetais/química , Galactanos/química , Hidrólise , Ácido Cítrico/química , Oligossacarídeos/química , beta-Manosidase/metabolismo , Saccharomyces cerevisiae/metabolismo , Fermentação
15.
Int J Biol Macromol ; 268(Pt 1): 131590, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38621563

RESUMO

This work aimed to prepare a new system for daunorubicin (DNR) delivery to improve therapeutic efficiency and decrease unwanted side effects. Typically, at first, a carboxylic acid functional group containing metal-organic framework (UiO-66-COOH) was synthesized in a simple way. Then, a third generation of citric acid dendrimer (CAD G3) was grown on it (UiO-66-COOH-CAD G3). Finally, the system was functionalized with pre-modified hyaluronic acid (UiO-66-COOH-CAD-HA). SEM analysis displayed that the synthesized particles have a spherical shape with an average particle size ranging from 260 to 280 nm. An increase in hydrodynamic diameter from 223 nm for UiO-66-COOH to 481 nm for UiO-66-COOH-CAD-HA is a sign of success in the performed reactions. Also, the average pore size was calculated at about 4.04 nm. The DNR loading efficiency of UiO-66-COOH-CAD-HA was evaluated at ∼74 % (DNR@UiO-66-COOH-CAD-HA). It was observed that the drug release rate at a lower pH is more than higher pH. The maximum hemolysis of <3 % means that the UiO-66-COOH-CAD-HA is hemocompatible. The use of DNR-loaded UiO-66-COOH-CAD-HA led to cell-killing of 77.9 % for MDA-MB 231. These results specified the great potential of UiO-66-COOH-CAD-HA for tumor drug delivery, so it could be proposed as a new carrier for anticancer agents to minimize adverse effects and improve therapeutic efficacy.


Assuntos
Ácido Cítrico , Daunorrubicina , Dendrímeros , Portadores de Fármacos , Liberação Controlada de Fármacos , Ácido Hialurônico , Daunorrubicina/química , Daunorrubicina/farmacologia , Ácido Hialurônico/química , Ácido Cítrico/química , Dendrímeros/química , Humanos , Portadores de Fármacos/química , Estruturas Metalorgânicas/química , Hemólise/efeitos dos fármacos , Materiais Biocompatíveis/química , Sistemas de Liberação de Medicamentos , Tamanho da Partícula , Linhagem Celular Tumoral , Animais , Concentração de Íons de Hidrogênio , Ácidos Ftálicos
16.
Int J Biol Macromol ; 268(Pt 1): 131618, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38631593

RESUMO

This study aims to fabricate composite gels using nano citrus fiber (Nano-CF) derived from the hydrolysis process of citric acid (CA) with FeCl3, with a simultaneous exploration of its potential as an substitute to fats. Investigation of varying FeCl3 concentrations (0.01 to 0.03 mmol/g of CA) revealed a significant enhancement in the water-holding and oil-retention capacity of the Nano-CF. The meticulous synthesis of the composite gels involved integrating nano citrus fibers with konjac glucomannan (KGM) through high-speed shearing, followed by a comprehensive evaluation of its microstructure and physicochemical attributes. Increasing the Nano-CF concentration within the gels led to a synergistic interaction with KGM, resulting in enhanced viscosity, improved thermal stability, and restricted water molecule mobility within the system. The gels initially displayed reduced firmness, resilience, and adhesive characteristics, followed by subsequent improvement. When the ratio of Nano-CF to KGM was 0.5:1, the composite gels exhibited texture parameters, viscosity, and viscoelastic stability comparable to whipped animal cream formulations. These findings provide a new idea for the application of Nano-CF/KGM composite gels in whipped cream.


Assuntos
Ácido Cítrico , Compostos Férricos , Géis , Mananas , Mananas/química , Hidrólise , Ácido Cítrico/química , Viscosidade , Géis/química , Compostos Férricos/química , Cloretos/química , Citrus/química , Reologia
17.
Environ Pollut ; 350: 123934, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38588971

RESUMO

In the framework of a safe-by-design approach, we previously assessed the eco-safety of nanostructured cellulose sponge (CNS) leachate on sea urchin reproduction. It impaired gamete quality, gamete fertilization competence, and embryo development possibly due to the leaching of chemical additives used during the CNS synthesis process. To extend this observation and identify the component(s) that contribute to CNS ecotoxicity, in the present study, we individually screened the cytotoxic effects on sea urchin Arbacia lixula and Paracentrotus lividus gametes and embryos of the three main constituents of CNS, namely cellulose nanofibers, citric acid, and branched polyethylenimine. The study aimed to minimize any potential safety risk of these components and to obtain an eco-safe CNS. Among the three CNS constituents, branched polyethylenimine resulted in the most toxic agent. Indeed, it affected the physiology and fertilization competence of male and female gametes as well as embryo development in both sea urchin species. These results are consistent with those previously reported for CNS leachate. Moreover, the characterisation of CNS leachate confirmed the presence of detectable branched polyethylenimine in the conditioned seawater even though in a very limited amount. Altogether, these data indicate that the presence of branched polyethylenimine is a cause-effect associated with a significant risk in CNS formulations due to its leaching upon contact with seawater. Nevertheless, the suggested safety protocol consisting of consecutive leaching treatments and conditioning of CNS in seawater can successfully ameliorate the CNS ecotoxicity while maintaining the efficacy of its sorbent properties supporting potential environmental applications.


Assuntos
Celulose , Ácido Cítrico , Nanofibras , Polietilenoimina , Reprodução , Ouriços-do-Mar , Poluentes Químicos da Água , Animais , Celulose/toxicidade , Celulose/química , Polietilenoimina/toxicidade , Polietilenoimina/química , Ácido Cítrico/química , Ácido Cítrico/toxicidade , Poluentes Químicos da Água/toxicidade , Reprodução/efeitos dos fármacos , Nanofibras/toxicidade , Nanofibras/química , Feminino , Ouriços-do-Mar/efeitos dos fármacos , Masculino , Paracentrotus/efeitos dos fármacos
18.
J Dent ; 145: 104977, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38582434

RESUMO

OBJECTIVE: This study compared the protective effect of an experimental TiF4/Chitosan toothpaste with a commercial toothpaste on the prevention of erosive tooth wear (ETW) in situ. METHODS: Fifteen subjects took part in this crossover and double-blind study, in which they wore a palatal appliance containing 4 bovine enamel and 4 dentin in 3 phases (5 days each). Half of the samples were subjected to erosive challenges (90 s in 0.1 % citric acid, pH 2.5, 4 times/day), and the other half to erosive plus abrasive challenges (15 s plus 45 s of contact, 2 times/day). The phases corresponded to the application of the different toothpastes: 1) TiF4 (1400 ppm F-) plus Chitosan, 2) Elmex®, Erosion Protection (1400 ppm F-, Chitosan), and 3) Placebo (negative control). Tooth wear was measured using contact profilometry (µm) and submitted to two-way RM ANOVA/Tukey test (p < 0.05). RESULTS: No significant differences were detected between the experimental and commercial toothpastes, regardless of the challenge on both tissues. Both significantly reduce ETW compared to negative control (p < 0.0006). Tooth wear was increased by brushing only on eroded enamel (p < 0.01), but not on dentin (p = 0.6085). TiF4/Chitosan [erosion 2.98 ± 1.12 µm vs. erosion and abrasion 3.12 ± 1.33 µm] and Elmex® toothpastes [erosion 2.35 ± 0.93 µm vs. erosion and abrasion 2.98 ± 1.0 µm] minimized the impact of brushing compared to placebo on enamel [erosion 4.62 ± 1.48 µm vs. erosion and abrasion 5.15 ± 1.50 µm]. CONCLUSIONS: TiF4 plus chitosan toothpastes showed to be effective in minimizing the ETW as the commercial toothpaste is in situ. CLINICAL RELEVANCE: The experimental toothpaste has similar effect against ETW compared to the commercial toothpaste. Considering the increased ETW prevalence worldwide, this result supports clinical trials and a possible application of this experimental anti-erosive toothpaste in the future.


Assuntos
Quitosana , Estudos Cross-Over , Esmalte Dentário , Dentina , Fluoretos , Titânio , Abrasão Dentária , Erosão Dentária , Cremes Dentais , Quitosana/uso terapêutico , Erosão Dentária/prevenção & controle , Cremes Dentais/uso terapêutico , Animais , Esmalte Dentário/efeitos dos fármacos , Método Duplo-Cego , Humanos , Bovinos , Dentina/efeitos dos fármacos , Dentina/patologia , Adulto , Fluoretos/uso terapêutico , Abrasão Dentária/prevenção & controle , Adulto Jovem , Feminino , Masculino , Ácido Cítrico/efeitos adversos , Escovação Dentária , Diaminas
19.
eNeuro ; 11(4)2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38649278

RESUMO

Attending to salient sensory attributes of food, such as tastes that are new, displeasing, or unexpected, allows the procurement of nutrients without food poisoning. Exposure to new tastes is known to increase norepinephrine (NE) release in taste processing forebrain areas, yet the central source for this release is unknown. Locus ceruleus norepinephrine neurons (LC-NE) emerge as a candidate in signaling salient information about taste, as other salient sensory stimuli (e.g., visual, auditory, somatosensation) are known to activate LC neurons. To determine if LC neurons are sensitive to features of taste novelty, we used fiber photometry to record LC-NE activity in water-restricted mice that voluntarily licked either novel or familiar substances of differential palatability (saccharine, citric acid). We observed that LC-NE activity was suppressed during lick bursts and transiently activated upon the termination of licking and that these dynamics were independent of the familiarity of the substance consumed. We next recorded LC dynamics during brief and unexpected consumption of tastants and found no increase in LC-NE activity, despite their responsiveness to visual and auditory stimuli, revealing selectivity in LC's responses to salient sensory information. Our findings suggest that LC activity during licking is not influenced by taste novelty, implicating a possible role for non-LC noradrenergic nuclei in signaling critical information about taste.


Assuntos
Locus Cerúleo , Camundongos Endogâmicos C57BL , Norepinefrina , Paladar , Animais , Locus Cerúleo/fisiologia , Masculino , Norepinefrina/metabolismo , Paladar/fisiologia , Camundongos , Percepção Gustatória/fisiologia , Ácido Cítrico/metabolismo , Sacarina/administração & dosagem , Neurônios/fisiologia , Feminino , Comportamento Animal/fisiologia
20.
Biomed Mater ; 19(3)2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38636498

RESUMO

Dental cement residues exacerbate peri-implant tissue irritation and peri-implantitis. The present study aims to evaluate the cytotoxicity, physiochemical, optical, and rheological properties of carbon quantum dots (CQDs) impregnated glass ionomer cement (GIC). Surface passivated fluorescent CQDs were synthesized using citric acid via thermal decomposition and blended with GIC. Characterization studies and rheological measurements were made to evaluate their performance. 3D-printed dental implant models cemented with GIC and GIC-CQD were compared to analyze excess cement residues. MTT assay was performed with human dental pulp stem cells (hDPSCs) and statistically analyzed using ANOVA and Tukey's test. CQDs with a particle dimension of ∼2 nm were synthesized. The amorphous property of GIC-CQD was confirmed through XRD. The fluorescence properties of GIC-CQD showed three times higher emission intensity than conventional GIC. GIC-CQD attained maturation with a setting time extended by 64 s than GIC. Cement residue of size 2 mm was detected with a UV light excitation at a distance between 5 to 10 cm. Biocompatibility at 0.125 mg ml-1dilution concentrations of GIC-CQD showed viability greater than 80% to hDPSCs. For the first time, we report that CQDs-impregnated GIC is a unique and cost-effective strategy for in-situ detection of excess cement rapidly using a hand-held device. A novel in-situ rapid detection method enables the dentist to identify residual cement of size less than 2 mm during the implantation. Therefore, GIC-CQD would replace conventional GIC and help in the prevention of peri-implant diseases.


Assuntos
Carbono , Polpa Dentária , Cimentos de Ionômeros de Vidro , Teste de Materiais , Pontos Quânticos , Pontos Quânticos/química , Humanos , Carbono/química , Cimentos de Ionômeros de Vidro/química , Polpa Dentária/citologia , Sobrevivência Celular/efeitos dos fármacos , Implantes Dentários , Peri-Implantite/prevenção & controle , Células-Tronco/citologia , Impressão Tridimensional , Materiais Biocompatíveis/química , Reologia , Ácido Cítrico/química
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