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1.
J Cell Mol Med ; 28(7): e18206, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38494858

RESUMO

Glioblastoma multiforme (GBM) is a highly aggressive and lethal form of primary brain tumour. Borax has been demonstrated to exhibit anti-cancer activity through cell death pathways. However, the specific impact of borax on ferroptosis in GBM is not well-established, and the underlying regulatory mechanisms remain unclear. Initially, the effective concentration of borax on cell viability and proliferation in U251 and A172 cells was determined. Subsequently, the effects of borax on the wound healing were analysed. Nuclear factor erythroid 2-related factor 2 (NRF2), glutathione peroxidase 4 (GPx4), glutathione (GSH), HSP70 protein 5 (HSPA5), malondialdehyde (MDA) levels and caspase-3/7 activity were determined in borax-treated and untreated cells. Finally, the protein expression levels of HSPA5, NRF2 and GPx4 were analysed. Borax suppressed cell viability and proliferation in U251 and A172 cells in a concentration- and time-dependent manner. In addition, borax treatment decreased GPx4, GSH, HSPA5 and NRF2 levels in U251 and A172 cells while increasing MDA levels and caspase-3/7 activity. Moreover, borax reduced mRNA and protein levels of HSPA5, NRF2 and GPx4 in U251 and A172 cells. Consequently, borax may induce ferroptosis in GBM cells and regulate the associated regulatory mechanisms targeting NRF2 and HSPA5 pathways. This knowledge may contribute to the development of novel therapeutic approaches targeting ferroptosis in GBM and potentially improve patient outcomes.


Assuntos
Boratos , Ferroptose , Glioblastoma , Humanos , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Fator 2 Relacionado a NF-E2/genética , Caspase 3/genética , Glutationa , Proteínas de Choque Térmico HSP70
2.
Plant J ; 113(6): 1310-1329, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36658763

RESUMO

Cross-linking of the cell-wall pectin domain rhamnogalacturonan-II (RG-II) via boron bridges between apiose residues is essential for normal plant growth and development, but little is known about its mechanism or reversibility. We characterized the making and breaking of boron bridges in vivo and in vitro at 'apoplastic' pH. RG-II (13-26 µm) was incubated in living Rosa cell cultures and cell-free media with and without 1.2 mm H3 BO3 and cationic chaperones (Ca2+ , Pb2+ , polyhistidine, or arabinogalactan-protein oligopeptides). The cross-linking status of RG-II was monitored electrophoretically. Dimeric RG-II was stable at pH 2.0-7.0 in vivo and in vitro. In-vitro dimerization required a 'catalytic' cation at all pHs tested (1.75-7.0); thus, merely neutralizing the negative charge of RG-II (at pH 1.75) does not enable boron bridging. Pb2+ (20-2500 µm) was highly effective at pH 1.75-4.0, but not 4.75-7.0. Cationic peptides were effective at approximately 1-30 µm; higher concentrations caused less dimerization, probably because two RG-IIs then rarely bonded to the same peptide molecule. Peptides were ineffective at pH 1.75, their pH optimum being 2.5-4.75. d-Apiose (>40 mm) blocked RG-II dimerization in vitro, but did not cleave existing boron bridges. Rosa cells did not take up d-[U-14 C]apiose; therefore, exogenous apiose would block only apoplastic RG-II dimerization in vivo. In conclusion, apoplastic pH neither broke boron bridges nor prevented their formation. Thus boron-starved cells cannot salvage boron from RG-II, and 'acid growth' is not achieved by pH-dependent monomerization of RG-II. Divalent metals and cationic peptides catalyse RG-II dimerization via co-ordinate and ionic bonding respectively (possible and impossible, respectively, at pH 1.75). Exogenous apiose may be useful to distinguish intra- and extra-protoplasmic dimerization.


Assuntos
Boratos , Boro , Ramnogalacturonanos/análise , Chumbo/análise , Pectinas/química , Cátions , Parede Celular/química
3.
Anal Chem ; 96(5): 2264-2272, 2024 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-38266388

RESUMO

Lipid metabolism diseases have become a tremendous risk worldwide, along with the development of productivity and particular attention to public health. It has been an urgent necessity to exploit reliable imaging strategies for lipids and thus to monitor fatty liver diseases. Herein, by converting the NIR-I signal to the NIR-II signal with IR1061 for the monitoring of lipid, the in vivo imaging of fatty liver disease was promoted on the contrast and visual effect. The main advantages of the imaging promotion in this work included a long emission wavelength, rapid response, and high signal-background-ratio (SBR) value. After promoting the NIR-I signal to NIR-II signal, IR1061 achieved higher SBR value and exhibited a dose-dependent fluorescence intensity at 1100 nm along with the increase of the EtOH proportion as well as steady and selective optical responses toward liposomes. IR1061 was further applied in the in vivo imaging of lipid in fatty liver diseases. In spite of the differences in body weight gain and TC level between healthy mice and fatty liver diseases two models, IR1061 achieved high-resolution imaging in the liver region to monitor the fatty liver disease status. This work might be informatic for the clinical diagnosis and therapeutical treatments of fatty liver diseases.


Assuntos
Boratos , Metabolismo dos Lipídeos , Hepatopatias , Piranos , Animais , Camundongos , Imagem Óptica/métodos , Corantes Fluorescentes , Lipídeos
4.
Chemistry ; 30(31): e202304375, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38563634

RESUMO

The clinical translation of polysarcosine (pSar) as polyethylene glycol (PEG) replacement in the development of novel nanomedicines creates a broad demand of polymeric material in high-quality making high-purity sarcosine N-carboxyanhydride (Sar-NCA) as monomer for its production inevitable. Within this report, we present the use of triethyloxonium tetrafluoroborate in Sar-NCA synthesis with focus on amino acid and chloride impurities to avoid the sublimation of Sar-NCAs. With a view towards upscaling into kilogram or ton scale, a new methodology of monomer purification is introduced by utilizing the Meerwein's Salt triethyloxonium tetrafluoroborate to remove chloride impurities by covalent binding and converting chloride ions into volatile products within a single step. The novel straightforward technique enables access to monomers with significantly reduced chloride content (<100 ppm) compared to Sar-NCA derived by synthesis or sublimation. The derived monomers enable the controlled-living polymerization in DMF and provide access to pSar polymers with Poisson-like molecular weight distribution within a high range of chain lengths (Xn 25-200). In conclusion, the reported method can be easily applied to Sar-NCA synthesis or purification of commercially available pSar-NCAs and eases access to well-defined hetero-telechelic pSar polymers.


Assuntos
Cloretos , Polimerização , Sarcosina , Sarcosina/química , Sarcosina/análogos & derivados , Cloretos/química , Polietilenoglicóis/química , Polímeros/química , Boratos/química , Anidridos/química , Peptídeos
5.
Biomacromolecules ; 25(1): 290-302, 2024 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-38065622

RESUMO

The prodrug strategy for its potential to enhance the pharmacokinetic and/or pharmacodynamic properties of drugs, especially chemotherapeutic agents, has been widely recognized as an important means to improve therapeutic efficiency. Irinotecan's active metabolite, 7-ethyl-10-hydroxycamptothecin (SN38), a borate derivative, was incorporated into a G-quadruplex hydrogel (GB-SN38) by the ingenious and simple approach. Drug release does not depend on carboxylesterase, thus bypassing the side effects caused by ineffective activation, but specifically responds to the ROS-overexpressed tumor microenvironment by oxidative hydrolysis of borate ester that reduces serious systemic toxicity from nonspecific biodistribution of SN38. Comprehensive spectroscopy was used to define the structural and physicochemical characteristics of the drug-loaded hydrogel. The GB-SN38 hydrogel's high level of biosafety and notable tumor-suppressive properties were proven in in vitro and in vivo tests.


Assuntos
Pró-Fármacos , Pró-Fármacos/química , Distribuição Tecidual , Boratos , Linhagem Celular Tumoral , Hidrogéis/farmacologia , Camptotecina/farmacologia
6.
Biomacromolecules ; 25(6): 3432-3448, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38771294

RESUMO

Preventing bacterial infections is a crucial aspect of wound healing. There is an urgent need for multifunctional biomaterials without antibiotics to promote wound healing. In this study, we fabricated a guar gum (GG)-based nanocomposite hydrogel, termed GBTF, which exhibited photothermal antibacterial therapy for infected wound healing. The GBTF hydrogel formed a cross-linked network through dynamic borate/diol interactions between GG and borax, thereby exhibiting simultaneously self-healing, adaptable, and injectable properties. Additionally, tannic acid (TA)/Fe3+ nanocomplexes (NCs) were incorporated into the hydrogel to confer photothermal antibacterial properties. Under the irradiation of an 808 nm near-infrared laser, the TA/Fe3+ NCs in the hydrogel could rapidly generate heat, leading to the disruption of bacterial cell membranes and subsequent bacterial eradication. Furthermore, the hydrogels exhibited good cytocompatibility and hemocompatibility, making them a precandidate for preclinical and clinical applications. Finally, they could significantly promote bacteria-infected wound healing by reducing bacterial viability, accelerating collagen deposition, and promoting epithelial remodeling. Therefore, the multifunctional GBTF hydrogel, which was composed entirely of natural substances including guar gum, borax, and polyphenol/ferric ion NCs, showed great potential for regenerating infected skin wounds in clinical applications.


Assuntos
Antibacterianos , Galactanos , Hidrogéis , Mananas , Nanocompostos , Terapia Fototérmica , Gomas Vegetais , Cicatrização , Mananas/química , Mananas/farmacologia , Gomas Vegetais/química , Gomas Vegetais/farmacologia , Galactanos/química , Galactanos/farmacologia , Cicatrização/efeitos dos fármacos , Antibacterianos/farmacologia , Antibacterianos/química , Nanocompostos/química , Hidrogéis/química , Hidrogéis/farmacologia , Animais , Terapia Fototérmica/métodos , Camundongos , Taninos/química , Taninos/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Humanos , Escherichia coli/efeitos dos fármacos , Boratos
7.
Int J Legal Med ; 138(3): 1085-1092, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-37993753

RESUMO

Very little literature currently exists prescribing which maceration method to use when preparing infant human remains, resulting in bone quality that is suitable for forensic anthropological analysis. The aim of the study was to test five maceration methods to determine which is most suitable for infant remains for forensic anthropological analysis. The sample included five neonate pig carcasses (Sus scrofa domesticus), ranging between one to three days old. Five maceration methods were tested on the pig carcasses (one pig per maceration method) to determine their effectiveness. The methods included invertebrate maceration by meal worms, chemical maceration by bleach, chemical maceration by borax solution, enzymatic maceration by laundry detergent and sodium carbonate solution, and chemical maceration by sodium hypochlorite. A scoring method was created to assess the effectiveness of each maceration method. Invertebrate maceration and chemical maceration using bleach were the least successful methods of maceration (total maceration score = 8 respectively). Chemical maceration using borax and chemical maceration using sodium hypochlorite achieved complete maceration of the skeletal remains; however, they both resulted in artifacts that are unsuitable for forensic analysis (total maceration score = 14 respectively). Enzymatic maceration using laundry detergent and sodium carbonate was the most successful method (total maceration score = 17). The detergent technique subsequently successfully macerated all five sets of infant human remains. This study has validated that the enzymatic maceration technique using laundry detergent and sodium carbonate can be used to effectively macerate the remains of infant skeletal remains for forensic anthropological analysis.


Assuntos
Restos Mortais , Boratos , Carbonatos , Hipoclorito de Sódio , Recém-Nascido , Humanos , Detergentes , Antropologia Forense/métodos , Mudanças Depois da Morte
8.
Analyst ; 149(8): 2363-2373, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38454902

RESUMO

This paper describes the electrochemical behavior of five ß-blockers at the polarized liquid-liquid interface formed between aqueous solution (sodium chloride solution or Britton-Robinson buffers) and bis(triphenylphosphoranylidene)ammonium tetrakis(4-chlorophenyl)borate (BTPPATPBCl) dissolved in 1,2-dichloroethane (the organic phase). All measurements reported in this work were conducted using cyclic voltammetry (CV). The effects of the concentration of analytes, the pH of the aqueous phase, and applied electrochemical parameters on the analytical performance of the studied system are studied and discussed. The linear dynamic ranges (LDRs) of the studied ß-blockers were in the range of 5-200 µmol L-1 and the lowest limit of detection (LOD) value was determined for pindolol (LOD = 1.96 µM µmol L-1). The highest LOD value was 4.96 µmol L-1 found for nebivolol. In addition, physicochemical parameters such as the formal Galvani potential difference (Δaqorgϕ), formal Gibbs free energies of the ion transfer reaction (ΔaqorgG') and partition coefficients (log P'aq/org) for all studied molecules were determined. The latter were compared and correlated with the available literature values of log Poctanol. Finally, a standard addition method was used to determine the concentration of nebivolol in pharmaceutical preparations using a platform based on the electrified liquid-liquid interface.


Assuntos
Pindolol , Água , Nebivolol , Octanóis , Água/química , Boratos
9.
Macromol Rapid Commun ; 45(2): e2300512, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37837340

RESUMO

Epoxidized natural rubber (ENR) crosslinked using borax, which exhibits self-healing and self-repairing properties, is successfully developed. The crosslink formation of ENR by using borax under neutral and alkaline conditions is investigated. Fourier transform infrared spectroscopy (FTIR) shows that the borate-ester bond is formed in ENR prepared under both neutral and alkaline conditions, whereas boron nuclear magnetic resonance (11 B-NMR) results exhibit that the ENR prepared under alkaline conditions more actively forms crosslink networks with borax. Moreover, the crosslink density and gel content increase significantly with the presence of borax in alkaline conditions. The crosslink density and gel content of ENR with 10 phr borax are higher by 155% and 36%, respectively, than those of neat ENR. Furthermore, the formation of the crosslinking ENR by borax enhances self-healing and self-repairing properties. The healing efficiency significantly increases from 1.09% to 85.90%, when ENR is developed under alkaline conditions with 30 phr borax. These results represent the first successful demonstration of the efficient use of borax as a crosslinker in ENR, which exhibits its promising self-healing and self-repairing properties under atmospheric conditions without the need for external stimuli. The ENR prepared in this work holds great promise for various self-healing rubber applications.


Assuntos
Boratos , Borracha , Borracha/química , Compostos de Epóxi/química , Concentração de Íons de Hidrogênio
10.
J Nanobiotechnology ; 22(1): 229, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38720321

RESUMO

Efficiently removing excess reactive oxygen species (ROS) generated by various factors on the ocular surface is a promising strategy for preventing the development of dry eye disease (DED). The currently available eye drops for DED treatment are palliative, short-lived and frequently administered due to the short precorneal residence time. Here, we developed nanozyme-based eye drops for DED by exploiting borate-mediated dynamic covalent complexation between n-FeZIF-8 nanozymes (n-Z(Fe)) and poly(vinyl alcohol) (PVA) to overcome these problems. The resultant formulation (PBnZ), which has dual-ROS scavenging abilities and prolonged corneal retention can effectively reduce oxidative stress, thereby providing an excellent preventive effect to alleviate DED. In vitro and in vivo experiments revealed that PBnZ could eliminate excess ROS through both its multienzyme-like activity and the ROS-scavenging activity of borate bonds. The positively charged nanozyme-based eye drops displayed a longer precorneal residence time due to physical adhesion and the dynamic borate bonds between phenyboronic acid and PVA or o-diol with mucin. The in vivo results showed that eye drops could effectively alleviate DED. These dual-function PBnZ nanozyme-based eye drops can provide insights into the development of novel treatment strategies for DED and other ROS-mediated inflammatory diseases and a rationale for the application of nanomaterials in clinical settings.


Assuntos
Síndromes do Olho Seco , Soluções Oftálmicas , Espécies Reativas de Oxigênio , Soluções Oftálmicas/química , Soluções Oftálmicas/farmacologia , Síndromes do Olho Seco/tratamento farmacológico , Animais , Espécies Reativas de Oxigênio/metabolismo , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Córnea/efeitos dos fármacos , Córnea/metabolismo , Álcool de Polivinil/química , Humanos , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/farmacologia , Boratos/química , Nanopartículas/química , Masculino
11.
Ecotoxicol Environ Saf ; 270: 115883, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38157802

RESUMO

Cadmium (Cd) is a ubiquitous environmental pollutant, and Cd exposure harms human health, agriculture, and animal husbandry. The present study aimed to investigate the potential protective effect of dietary supplementation of calcium tetraborate (CTB) on productive performance, oxidative stress, cecal microflora, and histopathological changes in quail exposed to Cd. A total of one hundred twenty, 6-week-old Japanese quail (four females and two males/replicate) were divided into four groups (30 quails/group): the control group (feeding basic diet), CTB group (basic diet containing 300 mg/kg CaB4O7, 22.14% elemental B/kg diet), the Cd group (basic diet containing 100 mg/kg cadmium chloride (CdCl2) (total Cd content of 92.1 mg/kg)) and the CTB + Cd group (basic diet containing 300 mg/kg CTB and 100 mg/kg CdCl2). The results showed that Cd exposure caused decreased performance, increased the proportion of broken and soft-shelled eggs, induced oxidative stress, affected cecal microflora, epicardial hemorrhages in the heart, focal necrosis in the liver, degeneration in the kidneys, and degenerated and necrotic seminiferous tubules in the testicles. CTB prevented Cd-induced oxidative stress in liver tissue by increasing total antioxidant status and reducing total oxidant status. In addition, CTB improved egg production and feed conversion ratio (FCR). CTB protected the cecal microflora by inhibiting Enterobacteriaceae and promoting Lactobacillus. CTB also reduced Cd-induced histopathological damage in the heart, liver, kidneys, and testicles. In conclusion, these findings suggest that CTB could be used in Cd-challenged quail, and this compound provides new insights into the toxicity of environmental Cd.


Assuntos
Boratos , Cádmio , Microbioma Gastrointestinal , Animais , Feminino , Masculino , Humanos , Cádmio/toxicidade , Codorniz , Cálcio/farmacologia , Coturnix , Dieta , Estresse Oxidativo , Suplementos Nutricionais/análise , Ração Animal/análise
12.
Luminescence ; 39(4): e4732, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38556715

RESUMO

In the present work, glass samples in the (100 - x)B2O3-xLi2O binary system, with x varying from 30 to 50 mol%, were prepared using the conventional melting and moulding method, with the main objective of evaluating the thermoluminescence response when exposing these materials to ultraviolet (UV) radiation. Complementary analysis based on density, optical absorption on the UV-visible region (UV-vis absorbance), Fourier transform infrared spectroscopy on the medium region, X-ray diffraction, and differential thermal analysis measurements were performed. Thermoluminescence measurements of vitreous samples showed glow curves with at least one peak with a maximum temperature of ~170°C after exposure to UV radiation in the temperature range 50-250°C. Samples were also exposed to beta radiation in the temperature range 25-275°C, also showing single peaks with a maximum temperature of ~150°C.


Assuntos
Partículas beta , Boratos , Boratos/química , Compostos de Lítio , Temperatura
13.
Luminescence ; 39(3): e4714, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38506395

RESUMO

In this study, the melt quenching approach is used to synthesize a lead borate-strontium-based glass system doped with samarium ions. Modifications in the glass network structure arising from the addition of various concentrations of Sm3+ ions were investigated via Fourier transform infrared (FTIR) spectroscopy. FTIR analysis revealed B-O-B bridges, BO3 , and BO4 units are present. UV-vis-NIR spectroscopic measurement was performed to study the optical absorption spectra. Optical constants such as optical bandgap energies, refractive indices, and other related parameters were evaluated. The lifetime fluorescence decay was measured and ranged between 1.04 and 1.88 ns. The photoluminescence spectra in the range 500-750 nm revealed four transitions from the ground state 6 G5/2 to the excited states 6 H5/2 , 6 H7/2 , 6 H9/2 and 6 H11/2 and J-O theory was utilized to study these optical transitions for Sm3+ ions. Calculations of the oscillator strengths and J-O intensity parameters were performed and the obtained J-O parameters followed the sequence Ω4 > Ω6 > Ω2 . The ratio O/R indicated a high lattice asymmetry around the samarium ions. The values of lifetimes and branching ratios for the fabricated samples emphasized their suitability to be used in laser applications. The current glass samples are good candidates for orange and red emission devices.


Assuntos
Boratos , Tungstênio , Boratos/química , Samário/química , Íons , Vidro/química
14.
Pestic Biochem Physiol ; 198: 105716, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38225073

RESUMO

Land snails are the most harmful pests in agricultural fields. Eobania vermiculata is a widespread snail species that causes massive damage to all agricultural crops. Thus, the molluscicidal activity of calcium borate nanoparticles (CB-NPs) against Eobania vermiculata was evaluated and compared with metaldehyde (Gastrotox® E 5% G). The amorphous phase of CB-NPs was obtained after thermal treatment at a low temperature (500 °C) which conformed by X-ray diffraction (XRD) analysis. CB-NPs are composed of aggregated nano-sheets with an average thickness of 54 nm which enhanced their molluscicidal activity. These nano-sheets displayed meso-porous network architecture with pore diameters of 13.65 nm, and a 9.46 m2/g specific surface area. CB-NPs and metaldehyde (Gastrotox® E 5% G) exhibited molluscicidal effects on Eobania vermiculata snails with median lethal concentrations LC50 of 175.3 and 60.5 mg/l, respectively, after 72 h of exposure. The results also showed significant reductions of Eobania vermiculata snails hemocytes' mean total number, the levels of Testosterone (T) and Estrogen (E), alkaline phosphatase, acid phosphatase, albumin, and protein concentrations, succinate dehydrogenase, glucose, triglycerides and phospholipids levels, while significant increases in the phagocytic index and mortality index, both transaminases (ALT and AST) and glycogen phosphorylase concentration were observed after the exposure to LC50 of CB-NPs or metaldehyde (Gastrotox® E 5% G) compared to the control group. Therefore, CB-NPs could be used as an alternative molluscicide for controlling Eobania vermiculata, but further studies are needed to assess their effects on non-target organisms.


Assuntos
Acetaldeído/análogos & derivados , Boratos , Moluscocidas , Caramujos , Animais , Compostos de Cálcio/metabolismo , Compostos de Cálcio/farmacologia , Moluscocidas/farmacologia , Flores
15.
J Prosthet Dent ; 132(1): 267.e1-267.e10, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38622046

RESUMO

STATEMENT OF PROBLEM: Denture stomatitis can pose serious health risks, especially to older people. Chemical denture cleaning agents must be effective, yet not adversely affect the longevity of removable dentures. Ready-to-use (RTU) neutral pH electrolyzed oxidizing water (EOW) is an effective biocide against Candida albicans biofilms on denture resins, but the effects of daily disinfection with EOW on the physical and mechanical properties of resins have not been established. PURPOSE: The purpose of this in vitro study was to investigate the effects of simulated long-term exposure to RTU EOW on the color, surface characteristics, and flexural strength of denture base resins. MATERIAL AND METHODS: Heat-polymerized (HP), 3D printed (3D) and computer-aided design and computer-aided manufacture (CAD-CAM)-milled (CC) denture resin specimens (square: 20×20×3.3 mm; beam: 64×10×3.3 mm) were immersed in tap water (TW), RTU EOW (Neutral Anolyte ANK; Envirolyte; EOW), or a commercial denture cleaning tablet solution (Polident 3-Minute; Glaxo SmithKline; PD), mimicking a 5-minute once daily disinfection routine performed up to 3.0 years. Color and surface roughness were recorded (n=3, squares), and changes in color (∆E00) and surface roughness (∆Ra) were calculated. Flexural strength (n=12, beams) and surface hardness (n=18, beams) were measured with a universal testing machine. The fractured surfaces of specimens were examined by scanning electron microscopy and energy dispersive spectroscopy. Data were assessed by performing the Shapiro-Wilk or D'Agostino and Pearson normality tests. Two-way ANOVA or the Kruskal-Wallis test with a post hoc Tukey HSD or Dunn multiple comparisons (α=.05) was used for statistical analyses. RESULTS: No significant changes were found in either color or surface roughness for HP, 3D, and CC resins after 1.5-year and 3.0-year immersion in any of the agents (P>.05). The surface hardness of 3D resins reduced by 14% with TW and by 23% with EOW and PD at 3.0 years. The flexural strengths of all 3 resins were unaffected by 3.0-year immersion (P>.05). CONCLUSIONS: Simulated long-term immersion disinfection with RTU neutral pH EOW did not adversely affect the physical and mechanical properties of HP or CC denture resins.


Assuntos
Bases de Dentadura , Higienizadores de Dentadura , Propriedades de Superfície , Água , Água/química , Concentração de Íons de Hidrogênio , Higienizadores de Dentadura/química , Teste de Materiais , Resistência à Flexão , Humanos , Materiais Dentários/química , Desenho Assistido por Computador , Técnicas In Vitro , Eletrólise , Resinas Acrílicas/química , Cor , Boratos , Sulfatos
16.
Molecules ; 29(1)2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38202834

RESUMO

This article applies nuclear magnetic resonance technology to the study of boron-containing traditional Chinese medicine, in order to explore the morphological evolution of boron elements in traditional Chinese medicine. Borax is a traditional Chinese medicine with anti-corrosion, anti-inflammatory, antibacterial, and anticonvulsant effects. It is made by boiling, removing stones, and drying borax minerals like borate salts. This article introduces an 11B nuclear magnetic resonance method for identifying and characterizing boron-containing compounds in TCM. We applied this technology to borax aqueous solutions in different chemical environments and found that with boron mixed in the form of SP2 hybridization in equilateral triangles and SP3 hybridization in equilateral tetrahedra, the pH changes in alkaline environments significantly affected the ratio of the two. At the same time, it was found that in addition to the raw material peak, boron signals of other boron-containing compounds were also detected in 20 commercially available boron-containing TCM preparations. These new boron-containing compounds may be true pharmaceutical active ingredients, and adding them directly to the formula can improve quality and safety. This article describes the detection of 11B NMR in boron-containing traditional Chinese medicine preparations. It is simple, non-destructive, and can provide chemical fingerprint studies for boron-containing traditional Chinese medicine.


Assuntos
Boratos , Boro , Medicina Tradicional Chinesa , Espectroscopia de Ressonância Magnética
17.
Angew Chem Int Ed Engl ; 63(29): e202404286, 2024 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-38712936

RESUMO

Perhalogenated closo-borates represent a new class of membrane carriers. They owe this activity to their chaotropicity, which enables the transport of hydrophilic molecules across model membranes and into living cells. The transport efficiency of this new class of cluster carriers depends on a careful balance between their affinity to membranes and cargo, which varies with chaotropicity. However, the structure-activity parameters that define chaotropic transport remain to be elucidated. Here, we have studied the modulation of chaotropic transport by decoupling the halogen composition from the boron core size. The binding affinity between perhalogenated decaborate and dodecaborate clusters carriers was quantified with different hydrophilic model cargos, namely a neutral and a cationic peptide, phalloidin and (KLAKLAK)2. The transport efficiency, membrane-lytic properties, and cellular toxicity, as obtained from different vesicle and cell assays, increased with the size and polarizability of the clusters. These results validate the chaotropic effect as the driving force behind the membrane transport propensity of boron clusters. This work advances our understanding of the structural features of boron cluster carriers and establishes the first set of rational design principles for chaotropic membrane transporters.


Assuntos
Boro , Boro/química , Boro/metabolismo , Humanos , Transporte Biológico , Compostos de Boro/química , Compostos de Boro/metabolismo , Interações Hidrofóbicas e Hidrofílicas , Boratos/química , Boratos/metabolismo
18.
Electrophoresis ; 44(19-20): 1607-1614, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37551057

RESUMO

SDS capillary gel electrophoresis is a widely used in the biopharma and the biomedical fields for rapid size separation of proteins. However, very limited information is available on the use of dilute and ultra-dilute sieving matrices for SDS-protein analysis. Here, background electrolytes (BGEs) containing 1%-0% dextran were used in borate-based BGE to separate a protein sizing ladder (PSL) ≤225 kDa and the intact and subunit forms of a therapeutic monoclonal antibody (mAb). The separation performance for the PSL and mAb components differed significantly with decreasing dextran concentration. Ferguson and reptation plots were used to elucidate the separation mechanism. Highly diluted dextran solutions resulted in linear Ferguson plots for both solute types (cf. Ogston theory) in spite of this model assumes a rigid pore structure, thus cannot describe the separation mechanism in ultra-dilute polymer solutions with no reticulations. The saddle differences between the resolution of the PSL and the intact/subunit mAb forms in ultra-dilute dextran-borate matrices suggested the importance of shape selectivity, manifested by the adequate separation of the SDS covered intact as well as light and heavy chain subunits of the therapeutic mAb even at zero dextran concentration.


Assuntos
Boratos , Dextranos , Dodecilsulfato de Sódio/química , Eletroforese Capilar/métodos , Proteínas/análise
19.
Biomacromolecules ; 24(11): 5364-5370, 2023 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-37906107

RESUMO

Herein, a pH-responsive dual cross-linked hydrogel for controlled drug release is presented. The hydrogel was constructed with reversible borate ester bonds and crystalline poly(vinyl alcohol). By changing the environmental pH, its physicochemical characteristics, including rheological properties, mechanical properties, microstructural features, and the biocompatibility of the gels, were evaluated. The gels at tumor acidic conditions exhibited swelling and lower compressive strength and modulus than those in a physiological environment, which was attributed to the pH-responsive borate ester bonds and the protonation of amine groups on the PEI polyelectrolyte. Importantly, the drug-encapsulated biocompatible hydrogel showed sustained and increased release under an acidic environment, and it followed the Fickian diffusion mechanism. Therefore, it exemplifies that borate ester bond-based pH-responsive biomaterials have high promise in biomedical research, especially for drug delivery.


Assuntos
Boratos , Hidrogéis , Hidrogéis/química , Sistemas de Liberação de Medicamentos , Concentração de Íons de Hidrogênio , Ésteres , Liberação Controlada de Fármacos
20.
Biomacromolecules ; 24(7): 3397-3410, 2023 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-37379247

RESUMO

Bacterial infection, prolonged inflammation, and insufficient angiogenesis are the main challenges for effective wound repair. In this work, we developed a stretchable, remodeling, self-healing, and antibacterial multifunctional composite hydrogel for infected wound healing. The hydrogel was prepared using tannic acid (TA) and phenylboronic acid-modified gelatin (Gel-BA) through hydrogen bonding and borate ester bonds and incorporated iron-containing bioactive glasses (Fe-BGs) with uniform spherical morphologies and amorphous structures to achieve GTB composite hydrogels. On one hand, the chelation of Fe3+ in Fe-BGs with TA endowed the hydrogel with good photothermal synergistic antibacterial ability; on the other hand, the bioactive Fe3+ and Si ions contained in Fe-BGs can recruit cells and synergistically promote blood vessel formation. In vivo animal experiments showed that the GTB hydrogels remarkably accelerated infected full-thickness skin wound healing by improving granulation tissue formation, collagen deposition, and the formation of nerves and blood vessels while decreasing inflammation. This hydrogel with a dual synergistic effect and ″one stone, two birds″ strategy holds immense potential for wound dressing applications.


Assuntos
Gelatina , Hidrogéis , Animais , Gelatina/farmacologia , Hidrogéis/farmacologia , Antibacterianos/farmacologia , Bandagens , Boratos
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