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1.
Sci Rep ; 14(1): 9027, 2024 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-38641640

RESUMO

Copper-doped ZnO nanoparticles with the formula Zn1-x(Cu)O, where x = 0.0, 0.03, 0.05, and 0.07 were produced using the co-precipitation process. Physical, chemical, and structural properties were properly examined. Powdered X-ray diffraction (P-XRD) patterns revealed the formation of hexagonal wurtzite crystal structure in all samples, through atomic substitutional incorporation in the Cu-doped ZnO lattice. The presence of Cu ions and their dissolution in the host ZnO crystal structure was supported by FT-IR spectra. HR-TEM images were used to assess the average size, morphology, and shape regularity of the synthesized samples. The form and homogeneity of the ZnO changed when Cu ions were substituted, as evidenced by FE-SEM/EDX analysis. The presence of copper signals in the Cu-doped samples indicates that the doping was successful. The decrease in zeta potential with an increased copper doping percentage designates that the nanoparticles (NPs) are more stable, which could be attributed to an increase in the ionic strength of the aqueous solution. The synthesized NPs were evaluated for their substantial in vitro antioxidant properties. In addition, the antimicrobial efficacy of the materials was tested against pathogenic microorganisms. Regarding the anti-diabetic activity, the 7Cu ZnO sample showed the highest inhibitory effect on the α-amylase enzyme. No variations were observed in the activities of the acetylcholinesterase enzyme (AChE) and proteinase enzymes with ZnO and samples doped with different concentrations of Cu. Therefore, further studies are recommended to reveal the in-vitro anti-diabetic activity of the studied doped samples. Finally, molecular docking provided valuable insights into the potential binding interactions of Cu-doped ZnO with α-amylase, FabH of E. coli, and Penicillin-binding proteins of S. aureus. These outcomes suggest that the prepared materials may have an inhibitory effect on enzymes and hold promise in the battle against microbial infections and diabetes.


Assuntos
Óxido de Zinco , Óxido de Zinco/farmacologia , Óxido de Zinco/química , Simulação de Acoplamento Molecular , Espectroscopia de Infravermelho com Transformada de Fourier , Cobre/química , Escherichia coli , Staphylococcus aureus , Acetilcolinesterase , Íons/farmacologia , alfa-Amilases
2.
ACS Appl Mater Interfaces ; 16(15): 19205-19213, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38591860

RESUMO

An artificial nociceptor, as a critical and special bionic receptor, plays a key role in a bioelectronic device that detects stimuli and provides warnings. However, fully exploiting bioelectronic applications remains a major challenge due to the lack of the methods of implementing basic nociceptor functions and nociceptive blockade in a single device. In this work, we developed a Pt/LiSiOx/TiN artificial nociceptor. It had excellent stability under the 104 endurance test with pulse stimuli and exhibited a significant threshold current of 1 mA with 1 V pulse stimuli. Other functions such as relaxation, inadaptation, and sensitization were all realized in a single device. Also, the pain blockade function was first achieved in this nociceptor with over a 25% blocking degree, suggesting a self-protection function. More importantly, an obvious depression was activated by a stimulus over 1.6 V due to the cooperative effects of both lithium ions and oxygen ions in LiSiOx and the dramatic accumulation of Joule heat. The conducting channel ruptured partially under sequential potentiation, thus achieving nociceptive blockade, besides basic functions in one single nociceptor, which was rarely reported. These results provided important guidelines for constructing high-performance memristor-based artificial nociceptors and opened up an alternative approach to the realization of bioelectronic systems for artificial intelligence.


Assuntos
Inteligência Artificial , Nociceptores , Humanos , Nociceptores/fisiologia , Dor , Biônica , Íons/farmacologia
3.
World J Gastroenterol ; 30(10): 1280-1286, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38596495

RESUMO

Yu et al's study in the World Journal of Gastroenterology (2023) introduced a novel regimen of Vonoprazan-amoxicillin dual therapy combined with Saccharomyces boulardii (S. boulardii) for the rescue therapy against Helicobacter pylori (H. pylori), a pathogen responsible for peptic ulcers and gastric cancer. Vonoprazan is a potassium-competitive acid blocker renowned for its rapid and long-lasting acid suppression, which is minimally affected by mealtime. Compared to proton pump inhibitors, which bind irreversibly to cysteine residues in the H+/K+-ATPase pump, Vonoprazan competes with the K+ ions, prevents the ions from binding to the pump and blocks acid secretion. Concerns with increasing antibiotic resistance, effects on the gut microbiota, patient compliance, and side effects have led to the advent of a dual regimen for H. pylori. Previous studies suggested that S. boulardii plays a role in stabilizing the gut barrier which improves H. pylori eradication rate. With an acceptable safety profile, the dual-adjunct regimen was effective regardless of prior treatment failure and antibiotic resistance profile, thereby strengthening the applicability in clinical settings. Nonetheless, S. boulardii comes in various formulations and dosages, warranting further exploration into the optimal dosage for supplementation in rescue therapy. Additionally, larger, randomized, double-blinded controlled trials are warranted to confirm these promising results.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Pirróis , Saccharomyces boulardii , Sulfonamidas , Humanos , Amoxicilina/uso terapêutico , Antibacterianos/efeitos adversos , Infecções por Helicobacter/tratamento farmacológico , Claritromicina/uso terapêutico , Quimioterapia Combinada , Inibidores da Bomba de Prótons/efeitos adversos , ATPase Trocadora de Hidrogênio-Potássio , Íons/farmacologia , Íons/uso terapêutico , Resultado do Tratamento
4.
Shanghai Kou Qiang Yi Xue ; 33(1): 6-12, 2024 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-38583018

RESUMO

PURPOSE: Bioactive magnesium ions were successfully incorporated into the nanoporous titanium base coating by micro-arc oxidation(MAO), and its physical properties and osteogenic effects were explored. METHODS: Non-magnesium-containing and magnesium-containing titanium porous titanium coatings(MAO, MAO-mg) were prepared by changing the composition of MAO electrolyte and controlling the doping of magnesium in porous titanium coatings. The samples were characterized by scanning electron microscope (SEM), roughness, contact angle and energy dispersive X-ray spectrometer (EDS). Mg2+ release ability of magnesium-doped nanoporous titanium coatings was determined by inductively coupled plasma/optical emission spectrometer(ICP-OES). The structure of the cytoskeleton was determined by live/dead double staining, CCK-8 detection of material proliferation-toxicity, and staining of ß-actin using FITC-phalloidin. The effects of the coating on osteogenic differentiation in vitro were determined by alizarin red (ARS), alkaline phosphatase (ALP) staining and real-time polymerase chain reaction (qRT-PCR). SPSS 25.0 software package was used for statistical analysis. RESULTS: The MAO electrolyte with magnesium ions did not change the surface characteristics of the porous titanium coating. Each group prepared by MAO had similar microporous structure(P>0.05). There was no significant difference in surface roughness and contact angle between MAO treatment group (MAO, MAO-mg)(P>0.05), but significantly higher than that of Ti group (P<0.05). With the passage of cell culture time, MAO-mg group promoted cell proliferation (P<0.05). MAO-mg group was significantly higher than other groups in ALP and ARS staining. The expression of Runx2 mRNA (P<0.05), ALP(P<0.05) and osteocalcin OCN(P<0.05) in MAO-mg group was significantly higher than that in Ti and MAO groups. CONCLUSIONS: MAO successfully prepared magnesium-containing nanoporous titanium coating, and showed a significant role in promoting osteogenic differentiation.


Assuntos
Nanoporos , Titânio , Titânio/farmacologia , Magnésio/química , Magnésio/farmacologia , Osteogênese/genética , Eletrólitos/farmacologia , Íons/farmacologia , Propriedades de Superfície , Materiais Revestidos Biocompatíveis/farmacologia , Materiais Revestidos Biocompatíveis/química
5.
ACS Appl Mater Interfaces ; 16(13): 15687-15700, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38511302

RESUMO

Polyethylene terephthalate (PET) artificial ligaments, renowned for their superior mechanical properties, have been extensively adopted in anterior cruciate ligament (ACL) reconstruction surgeries. However, the inherent bio-inertness of PET introduces formidable barriers to graft-bone integration, a critical aspect of rehabilitation. Previous interventions, ranging from surface roughening to chemical modifications, have aimed to address this challenge; however, consistently effective techniques for inducing graft-bone integration remain scarce. Our study employed advanced surface-coating methodologies to introduce strontium-doped hydroxyapatite (SrHA) onto PET ligaments. Detailed scanning electron microscopy (SEM) examinations revealed a uniform and integrative coating of SrHA on PET fibers. Furthermore, spectroscopic analysis confirmed the steady release of strontium ions from the coated surface under physiological conditions. In-depth cellular studies proved that extracellular strontium emanating from SrHA-coated PET (PET@SrHA) ligaments actively steers the M2 macrophage polarization. Additionally, macrophages (Mφs) manifested a heightened secretion of prohealing cytokines when exposed to PET@SrHA. Subsequent investigations showed that these cytokines acted as mediators, activating integrin signaling pathways among macrophages, vascular endothelial cells, and osteoblasts. As a direct consequence, an increased rate of angiogenesis and osteogenic differentiation was observed, vital for graft-bone integration following ACL reconstruction with PET@SrHA ligaments. From a biochemical standpoint, our results pinpoint strontium ions as influential immunomodulators, sculpting the graft-bone interface's immune environment. This insight presents the SrHA-coating technique as a viable therapeutic strategy, holding sound promise for improving angiogenesis and osseointegration outcomes during ACL reconstruction using PET-based grafts.


Assuntos
Integrinas , Osteogênese , Citocinas , Angiogênese , Células Endoteliais , Hidroxiapatitas/química , Estrôncio/farmacologia , Estrôncio/química , Transdução de Sinais , Íons/farmacologia
6.
Biomater Sci ; 12(7): 1788-1800, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38390988

RESUMO

Biofilms formed by pathogenic bacteria present a persistent risk to human health. While the eradication of matured biofilms remains a formidable challenge, delaying or preventing their formation, which is coordinately regulated by quorum sensing (QS), presents a simpler and more advantageous strategy. Quercetin, a naturally occurring compound with anti-QS properties, has the potential to act as an antibiofilm agent. However, it is plagued by certain inherent drawbacks, including poor water solubility and limited bioavailability. Furthermore, solely blocking QS is not enough to prevent biofilm formation because it lacks bactericidal properties. To address these difficulties, we fabricated bi-functional nanoparticles through the co-assembly of quercetin and copper ions in a facile manner. The resulting quercetin/copper nanoparticles (QC NPs) demonstrated minimal cytotoxicity and hemolysis in vitro. In response to the low pH of microenvironments that were populated by bacterial colonies, the QC NPs underwent disassembly to release copper ions and quercetin. The former exterminated bacteria by disrupting the integrity of the cell membrane, while the latter disrupted the processes involved in QS that are responsible for the biofilm by downregulating the expression of specific genes, effectively preventing the formation of biofilms by both Gram-negative Pseudomonas aeruginosa and Gram-positive Staphylococcus aureus. In addition, the QC NPs were integrated into a bacterial cellulose membrane. The composite membrane proved to be highly effective at inhibiting biofilm formation in vitro and demonstrated the ability to reduce inflammatory responses and accelerate the healing of bacteria-infected wounds in vivo. Overall, the bi-functional QC NPs hold great potential for use in addressing the challenges associated with the management of bacterial biofilms.


Assuntos
Nanopartículas , Percepção de Quorum , Humanos , Quercetina/farmacologia , Cobre/farmacologia , Biofilmes , Antibacterianos/farmacologia , Antibacterianos/química , Bactérias , Íons/farmacologia , Pseudomonas aeruginosa
7.
Food Funct ; 15(5): 2587-2603, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38353975

RESUMO

Deer sinew as a by-product has high collagen and nutritional value. This study focuses on its hydrolysate being used as a calcium carrier to develop functional foods. The chelation mechanism was analyzed by SEM, EDS, UV-vis, FTIR, and fluorescence spectroscopy and zeta potential analysis after using peptide-sequenced deer sinew peptides for chelation with calcium ions. The results showed that the chelation of deer sinew peptides with calcium ions occurs mainly at the O and N atoms of carboxyl, amino and amide bonds. In vitro and in vivo studies revealed that deer sinew peptide-calcium chelate (DSPs-Ca) promoted the proliferation of MC3T3-E1 cells without toxic side effects and increased the alkaline phosphatase activity. The DSPs-Ca group improved the bone microstructure induced by low calcium, as well as up-regulated the expression of genes responsible for calcium uptake in the kidneys, as evidenced by serum markers, bone sections, bone parameters, and gene expression analyses in low-calcium-fed mice. From the above, it can be concluded that DSPs-Ca is expected to be a calcium supplement food for promoting bone health.


Assuntos
Cálcio , Cervos , Camundongos , Animais , Cálcio/metabolismo , Cervos/metabolismo , Proliferação de Células , Cálcio da Dieta/metabolismo , Peptídeos/farmacologia , Peptídeos/metabolismo , Íons/metabolismo , Íons/farmacologia , Osteoblastos
8.
Aging (Albany NY) ; 16(4): 3386-3403, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38345573

RESUMO

BACKGROUND: Cisplatin (DDP) is one of the important chemotherapy drugs for patients with advanced gastric cancer and metastasis, but its resistance is a bottleneck problem that affects clinical efficacy and patient survival. Eremias multiocellata (EM) is a traditional Chinese herbal medicine, which has been used in the treatment of precancerous lesions, gastric cancer, liver fibrosis, and other digestive diseases. However, the mechanism of reducing chemotherapy resistance to gastric cancer is still unclear. METHODS: We used the MTT assay to evaluate the proliferative viability of gastric cancer parental cell line MKN45 and its drug-resistant cell line MKN45/DDP, and compared their drug-resistance indices. The migration and invasion abilities of MKN45/DDP drug-resistant cells were evaluated using the Transwell assay. Apoptosis in MKN45/DDP drug-resistant cells was detected using flow cytometry. The effect of a combination of EM and cisplatin on the levels of reactive oxygen species (ROS) and lipid peroxides (LPO) in cisplatin-resistant gastric cancer cells was detected using ROS fluorescent probes and a lipid peroxidation assay kit in conjunction with flow cytometry. The effect of EM combined with cisplatin on the level of iron ions was detected by fluorescence probe and confocal laser technique. Hematoxylin-eosin staining (HE staining) was used to detect the histopathologic morphology of drug-resistant gastric cancer in nude mice. Ferroptosis-related proteins were measured using immunohistochemistry. Real-time fluorescence quantitative polymerase chain reaction (RT-qPCR) was used to detect tumor drug resistance-related genes. The NF-κB/Snail pathway-related proteins, PI3K/AKT/mTOR pathway-related proteins, and drug resistance-related proteins were detected by Western blot. RESULTS AND CONCLUSIONS: The results of in vitro and in vivo experiments showed that EM combined with DDP could effectively inhibit the migration and invasive ability of MKN45/DDP cells, as well as induce apoptosis of MKN45/DDP cells; the combination of the two drugs could significantly increase the levels of ROS, lipid peroxidation and divalent ferric ions in MKN45/DDP cells, at the same time reducing the levels of Ferroptosis-related proteins, which could induce Ferroptosis. In addition, EM combined with DDP can also exert the effect of reversing DDP resistance and increasing the sensitivity of gastric cancer drug-resistant cells to DDP by regulating the NF-κB/Snail signaling pathway, PI3K/AKT/mTOR signaling pathway, and the expression of drug resistance-related proteins and genes.


Assuntos
Cisplatino , Neoplasias Gástricas , Animais , Camundongos , Humanos , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Neoplasias Gástricas/genética , Resistencia a Medicamentos Antineoplásicos/genética , NF-kappa B , Proteínas Proto-Oncogênicas c-akt/metabolismo , Camundongos Nus , Fosfatidilinositol 3-Quinases , Espécies Reativas de Oxigênio , Apoptose , Serina-Treonina Quinases TOR , Íons/farmacologia , Íons/uso terapêutico , Linhagem Celular Tumoral , Proliferação de Células
9.
J Environ Radioact ; 273: 107396, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38325251

RESUMO

The irradiated Saccharomyces cerevisiae (Y-7) has good biosorption ability for strontium ions. To investigate the mechanism of strontium ion bioaccumulation in Y-7, we employed CRISPR/Cas9 gene editing technology to engineer Saccharomyces cerevisiae Y-7 and knock out the RSN1 gene, successfully constructing a RSN1 gene knockout strain (Y-7-rsn1Δ). When tested for strontium ion adsorption, the Y-7-rsn1Δ strain exhibited decreased capacity for adsorbing strontium ions and increased resistance to strontium ions. The results showed that RSN1 is involved in the transport of Sr2+, and observed significant decreases in intracellular Ca2+ of Y-7-rsn1Δ, indicating a strong correlation between bioaccumulation of Sr2+ and Ca2+. This demonstrated that the adsorption of strontium ions by Y-7 is regulated by the RSN1 gene. The knockout of the RSN1 gene resulted in the shift of the peak positions of carboxyl, amino, amide, hydroxyl, and phosphate groups on the cell surface.


Assuntos
Monitoramento de Radiação , Estrôncio , Estrôncio/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Adsorção , Técnicas de Inativação de Genes , Íons/metabolismo , Íons/farmacologia
10.
J Zhejiang Univ Sci B ; 25(1): 65-82, 2024 Jan 15.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-38163667

RESUMO

Magnesium-doped calcium silicate (CS) bioceramic scaffolds have unique advantages in mandibular defect repair; however, they lack antibacterial properties to cope with the complex oral microbiome. Herein, for the first time, the CS scaffold was functionally modified with a novel copper-containing polydopamine (PDA(Cu2+|)) rapid deposition method, to construct internally modified (*P), externally modified (@PDA), and dually modified (*P@PDA) scaffolds. The morphology, degradation behavior, and mechanical properties of the obtained scaffolds were evaluated in vitro. The results showed that the CS*P@PDA had a unique micro-/nano-structural surface and appreciable mechanical resistance. During the prolonged immersion stage, the release of copper ions from the CS*P@PDA scaffolds was rapid in the early stage and exhibited long-term sustained release. The in vitro evaluation revealed that the release behavior of copper ions ascribed an excellent antibacterial effect to the CS*P@PDA, while the scaffolds retained good cytocompatibility with improved osteogenesis and angiogenesis effects. Finally, the PDA(Cu2+)-modified scaffolds showed effective early bone regeneration in a critical-size rabbit mandibular defect model. Overall, it was indicated that considerable antibacterial property along with the enhancement of alveolar bone regeneration can be imparted to the scaffold by the two-step PDA(Cu2+) modification, and the convenience and wide applicability of this technique make it a promising strategy to avoid bacterial infections on implants.


Assuntos
Cobre , Alicerces Teciduais , Animais , Coelhos , Cobre/farmacologia , Alicerces Teciduais/química , Regeneração Óssea , Antibacterianos/farmacologia , Osteogênese , Cálcio , Íons/farmacologia
11.
Dalton Trans ; 53(6): 2826-2832, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38230617

RESUMO

Bacterial infections are a big challenge in clinical treatment, making it urgent to develop innovative antibacterial systems and therapies to combat bacterial infections. In this study, we developed a novel MOF-based synergistic antibacterial system (Eu@B-UiO-66/Zn) by loading a natural antibacterial substance (eugenol) with hierarchically porous MOF B-UiO-66 as a carrier and further complexing it with divalent zinc ions. Results indicate that the system achieved a controlled release of eugenol under pH responsive stimulation, with the complexation ability of eugenol and Zn2+ ions as a switch. Due to the destruction of a coordination bond between eugenol and Zn2+ ions by an acidic medium, the release of eugenol loaded in Eu@B-UiO-66/Zn reached 80% at pH 5.8, which was significantly higher than that under pH 8.0 (51%). Moreover, the inhibitory effect of Eu@B-UiO-66/Zn against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) after 24 h was 96.4% and 99.7%, respectively, owing to the synergistic antibacterial effect of eugenol and Zn2+ ions, which was significantly stronger than free eugenol and Eu@B-UiO-66. We hope that this strategy for constructing responsive MOF-based antibacterial carriers could have potential possibilities for the application of MOF materials in antibacterial fields.


Assuntos
Infecções Bacterianas , Estruturas Metalorgânicas , Ácidos Ftálicos , Humanos , Estruturas Metalorgânicas/química , Eugenol/farmacologia , Eugenol/química , Eugenol/uso terapêutico , Escherichia coli , Staphylococcus aureus , Antibacterianos/farmacologia , Antibacterianos/química , Bactérias , Infecções Bacterianas/tratamento farmacológico , Íons/farmacologia , Concentração de Íons de Hidrogênio
12.
Dalton Trans ; 53(5): 2218-2230, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38193719

RESUMO

Inspired by the emergence of resistance to currently available antifungal therapy and by the great potential of metal complexes for the treatment of various diseases, we synthesized three new silver(I) complexes containing clinically used antifungal azoles as ligands, [Ag(ecz)2]SbF6 (1, ecz is econazole), {[Ag(vcz)2]SbF6}n (2, vcz is voriconazole), and [Ag(ctz)2]SbF6 (3, ctz is clotrimazole), and investigated their antimicrobial properties. The synthesized complexes were characterized by mass spectrometry, IR, UV-vis and 1H NMR spectroscopy, cyclic voltammetry, and single-crystal X-ray diffraction analysis. In the mononuclear complexes 1 and 3 with ecz and ctz, respectively, the silver(I) ion has the expected linear geometry, in which the azoles are monodentately coordinated to this metal center through the N3 imidazole nitrogen atom. In contrast, the vcz-containing complex 2 has a polymeric structure in the solid state in which the silver(I) ions are coordinated by four nitrogen atoms in a distorted tetrahedral geometry. DFT calculations were done to predict the most favorable structures of the studied complexes in DMSO solution. All the studied silver(I) complexes have shown excellent antifungal and good to moderate antibacterial activities with minimal inhibitory concentration (MIC) values in the ranges of 0.01-27.1 and 2.61-47.9 µM on the selected panel of fungi and bacteria, respectively. Importantly, the complexes 1-3 have exhibited a significantly improved antifungal activity compared to the free azoles, with the most pronounced effect observed in the case of complex 2 compared to the parent vcz against Candida glabrata with an increase of activity by five orders of magnitude. Moreover, the silver(I)-azole complexes 2 and 3 significantly inhibited the formation of C. albicans hyphae and biofilms at the subinhibitory concentration of 50% MIC. To investigate the impact of the complex 3 more thoroughly on Candida pathogenesis, its effect on the adherence of C. albicans to A549 cells (human adenocarcinoma alveolar basal epithelial cells), as an initial step of the invasion of host cells, was studied.


Assuntos
Complexos de Coordenação , Prata , Humanos , Prata/farmacologia , Prata/química , Candida , Antifúngicos/farmacologia , Antifúngicos/química , Azóis/farmacologia , Candida albicans , Testes de Sensibilidade Microbiana , Íons/farmacologia , Nitrogênio , Complexos de Coordenação/farmacologia , Complexos de Coordenação/química
13.
Ecotoxicol Environ Saf ; 271: 116013, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38281433

RESUMO

The damage excessive neodymium (Nd) causes to animals and plants should not be underestimated. However, there is little research on the impact of pH and associated ions on the toxicity of Nd. Here, a biotic ligand model (BLM) was expanded to predict the effects of pH and chief anions on the toxic impact of Nd on wheat root elongation in a simulated soil solution. The results suggested that Nd3+ and NdOH2+ were the major ions causing phytotoxicity to wheat roots at pH values of 4.5-7.0. The Nd toxicity decreased as the activities of H+, Ca2+, and Mg2+ increased but not when the activities of K+ and Na+ increased. The results indicated that H+, Ca2+, and Mg2+ competed with Nd for binding sites. An extended BLM was developed to consider the effects of pH, H+, Ca2+, and Mg2+, and the following stability constants were obtained: logKNdBL = 2.51, logKNdOHBL = 3.90, logKHBL = 4.01, logKCaBL = 2.43, and logKMgBL = 2.70. The results demonstrated that the BLM could predict the Nd toxicity well while considering the competition of H+, Ca2+, Mg2+ and the toxic species Nd3+ and NdOH2+ for binding sites.


Assuntos
Neodímio , Poluentes do Solo , Neodímio/toxicidade , Triticum , Ligantes , Poluentes do Solo/toxicidade , Modelos Biológicos , Raízes de Plantas , Íons/farmacologia , Concentração de Íons de Hidrogênio
14.
J Mech Behav Biomed Mater ; 150: 106295, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38096611

RESUMO

OBJECTIVE: To evaluate the effect of ions released from surface pre-reacted glass-ionomer (S-PRG) filler on collagen morphology, remineralization, and ultimate tensile strength (UTS) of demineralized dentin. MATERIALS AND METHODS: Bovine incisor root dentins were demineralized with EDTA and divided into three treatment groups: 1) water (control); 2) S-PRG filler eluate; 3) 125 ppm sodium fluoride (NaF). After a 3-min treatment, the specimens were stored in simulated body fluid (SBF) for 3 months. Collagen morphology and remineralization were assessed using transmission electron microscopy (TEM), scanning electron microscopy (SEM), and Fourier-transform infrared spectroscopy (FTIR). Additionally, ultimate tensile strength (UTS) was measured. RESULTS: TEM and SEM demonstrated that S-PRG induced more effective remineralization compared to NaF, while the control group exhibited faint mineral deposition with collagen degradation. S-PRG displayed the most homogenous mineral deposition in collagen fibrils, along with closure of interfibrillar spaces. Extensive mineral precipitation was observed within dentinal tubules in the S-PRG group. In addition, S-PRG filler eluate demonstrated significantly higher phosphate-to-amide ratio and UTS compared to NaF and control groups (p < 0.05). CONCLUSIONS: Ion released from S-PRG filler positively influenced collagen morphology, remineralization, and ultimate tensile strength of demineralized dentin. CLINICAL SIGNIFICANCE: S-PRG filler enhances remineralization and improve the biomechanics of demineralized dentin.


Assuntos
Dentina , Dióxido de Silício , Animais , Bovinos , Resistência à Tração , Colágeno/farmacologia , Íons/farmacologia , Cimentos de Ionômeros de Vidro/química
15.
J Appl Toxicol ; 44(4): 553-563, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37950502

RESUMO

Neurotoxicity induced by psychoactive substances is often accompanied by an imbalance of intracellular calcium ions. It is unclear whether calcium ions play a role in the toxicity induced by psychoactive substances. In the present study, we aimed to evaluate the occurrence of calcium dysregulation and its contribution to cytotoxicity in human neurotypic SH-SY5Y cells challenged with a recently developed psychoactive substance 4-methylethcathinone (4-MEC). An increase in the intracellular calcium was detected by inductively coupled plasma atomic emission spectrometry and Fluo-3 AM dye in SH-SY5Y cells after being treated with 4-MEC. The increase of intracellular Ca2+ level mediated G0/G1 cell cycle arrest and ROS/endoplasmic reticulum stress-autophagy signaling pathways to achieve the toxicity of 4-MEC. In particular, N-acetyl-L-cysteine, a classical antioxidant, was found to be a potential treatment for 4-MEC-induced toxicity. Taken together, our results demonstrate that an increase in intracellular calcium content is one of the mechanisms of 4-MEC-induced toxicity. This study provides a molecular basis for the toxicity mechanism and therapeutic intervention of psychoactive substances.


Assuntos
Anfetaminas , Cálcio , Neuroblastoma , Propiofenonas , Humanos , Cálcio/metabolismo , Linhagem Celular Tumoral , Íons/farmacologia , Apoptose
16.
J Biochem Mol Toxicol ; 38(1): e23531, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37724821

RESUMO

Myocardial infarction (MI) is a common type of ischemic heart disease that affects millions of people worldwide. In recent times, nanotechnology has become a very promising field with immense applications. The current exploration was conducted to synthesize the chitosan-sodium alginate-polyethylene glycol-Ally isothiocyanate nanocomposites (CSP-AIso-NCs) and evaluate their beneficial roles against the isoproterenol (ISO)-induced MI in rats. The CSP-AIso-NCs were prepared and characterized by several characterization techniques. The MI was initiated in the rats by the administration of 85 mg/kg of ISO for 2 days and treated with 10 and 20 mg/kg of CSP-AIso-NCs for 1 month. The changes in heart weight and bodyweight were measured. The cardiac function markers were assessed with echocardiography. The lipid profiles, Na+, K+, and Ca2+ ions, cardiac biomarkers, antioxidant parameters, and inflammatory cytokines were assessed using corresponding assay kits. The histopathological study was done on the heart tissues. The UV spectral analysis revealed the maximum peak at 208 nm, which confirms the formation of CSP-AIso-NCs. The FT-IR analysis revealed the occurrence of different functional groups, and the crystallinity of the CSP-AIso-NCs was proved by the XRD analysis. DLS analysis indicated the size of the CSP-AIso-NCs at 146.50 nm. The CSP-AIso-NCs treatment increased the bodyweight and decreased the HW/BW ratio in the MI rats. The status of lipids was reduced, and HDL was elevated in the CSP-AIso-NCs administered to MI rats. CSP-AIso-NCs decreased the LVEDs, LVEDd, and NT-proBNP and increased the LVEF level. The oxidative stress markers were decreased, and the antioxidants were increased by the CSP-AIso-NCs treatment in the MI rats. The Na+ and Ca+ ions were reduced, and the K+ ions were increased by the CSP-AIso-NCs. The interleukin-1ß and tumor necrosis factor-α were also depleted, and Nrf-2 was improved in the CSP-AIso-NCs administered to MI rats. The histological study revealed the ameliorative effects of CSP-AIso-NCs. Overall, our outcomes revealed that the CSP-AIso-NCs are effective against the ISO-induced MI rats. Hence, it could be a hopeful therapeutic nanomedicine for MI treatment.


Assuntos
Quitosana , Infarto do Miocárdio , Humanos , Ratos , Animais , Isoproterenol/toxicidade , Quitosana/farmacologia , Alginatos/farmacologia , Alginatos/metabolismo , Alginatos/uso terapêutico , Polietilenoglicóis/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier , Infarto do Miocárdio/induzido quimicamente , Infarto do Miocárdio/tratamento farmacológico , Infarto do Miocárdio/patologia , Antioxidantes/metabolismo , Estresse Oxidativo , Íons/metabolismo , Íons/farmacologia , Íons/uso terapêutico , Miocárdio/metabolismo
17.
J Dairy Sci ; 107(2): 1211-1227, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37730173

RESUMO

The objective of this experiment was to examine the effects of supplementation and dose of rumen-protected choline (RPC) on markers of inflammation and metabolism in liver and mammary tissue during an intramammary lipopolysaccharide (LPS) challenge. Parous Holstein cows were blocked by calving month and randomly assigned within block to receive 45 g/d of RPC (20.4 g/d of choline ions; CHOL45), 30 g/d of RPC (13.6 g/d of choline ions; CHOL30), or no RPC (CON) as a top-dress starting 24 d before expected calving until 21 d postpartum. Cows were alternately assigned within treatment group to either receive an intramammary LPS challenge (200 µg in each rear quarter; Escherichia coli O111:B4) or not at 17 DIM (CHOL45, n = 9; CHOL45-LPS, n = 9; CHOL30, n = 11; CHOL30-LPS, n = 10; CON, n = 10; CON-LPS, n = 9). Hepatic and mammary tissues were collected from all cows on d 17 postpartum. Hepatic and mammary tissues were collected at ∼7.5 and 8 h, respectively, after the LPS challenge. An additional mammary biopsy was conducted on LPS-challenged cows (CHOL45-LPS, CHOL30-LPS, and CON-LPS) at 48 h postchallenge. Hepatic and mammary RNA copy numbers were quantified for genes involved in apoptosis, methylation, inflammation, oxidative stress, and mitochondrial function using NanoString technology. Targeted metabolomics was conducted only on mammary tissue samples (both 8 and 48 h biopsies) to quantify 143 metabolites including choline metabolites, amino acids, biogenic amines and derivatives, organic acids, carnitines, and glucose. Hepatic IFNG was greater in CHOL45 as compared with CON in unchallenged cows, suggesting an improvement in type 1 immune responses. Hepatic CASP3 was greater in CHOL45-LPS as compared with CON-LPS, suggesting greater apoptosis. Mammary IL6 was reduced in CHOL30-LPS cows as compared with CHOL45-LPS and CON-LPS (8 and 48 h). Mammary GPX4 and COX5A were reduced in CHOL30-LPS as compared with CON-LPS (8 h), and SDHA was reduced in CHOL30-LPS as compared with CON-LPS (8 and 48 h). Both CHOL30-LPS and CHOL45-LPS cows had lesser mammary ATP5J than CON-LPS, suggesting that dietary RPC supplementation altered mitochondrial function following LPS challenge. Treatment did not affect mammary concentrations of any metabolite in unchallenged cows, and only 4 metabolites were affected by dietary RPC supplementation in LPS-challenged cows. Mammary concentrations of isobutyric acid and 2 acyl-carnitines (C4:1 and C10:2) were reduced in CHOL45-LPS as compared with CHOL30-LPS and CON-LPS. Taken together, reductions in medium- and short-chain carnitines along with an increase in long-chain carnitines in mammary tissue from CHOL45-LPS cows suggests less fatty acid entry into the ß oxidation pathway. Although the intramammary LPS challenge profoundly affected markers for inflammation and metabolism in liver and mammary tissue, dietary RPC supplementation had minimal effects on inflammatory markers and the mammary metabolome.


Assuntos
Doenças dos Bovinos , Lipopolissacarídeos , Feminino , Bovinos , Animais , Lipopolissacarídeos/farmacologia , Colina/metabolismo , Suplementos Nutricionais , Lactação , Rúmen/metabolismo , Leite/química , Dieta/veterinária , Fígado/metabolismo , Inflamação/veterinária , Inflamação/metabolismo , Íons/análise , Íons/metabolismo , Íons/farmacologia , Doenças dos Bovinos/metabolismo
18.
Acta Biomater ; 174: 412-427, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38040077

RESUMO

Bioactive glass nanoparticles (BGNs) are well-recognized multifunctional biomaterials for bone tissue regeneration due to their capability to stimulate various cellular processes through released biologically active ions. Understanding the correlation between BGN composition and cellular responses is key to developing clinically usable BGN-based medical devices. This study investigated the influence of CaO content of binary SiO2-CaO BGNs (CaO ranging from 0 to 10 mol%) on osteogenic differentiation of rat bone marrow mesenchymal stem cells (rBMSCs) and in vivo bone regeneration in zebrafish osteoporosis model. The results showed that BGNs could promote osteogenic differentiation of rBMSCs by indirectly releasing active ions or directly interacting with rBMSCs by internalization. In both situations, BGNs of a higher CaO content could promote the osteogenic differentiation of rBMSCs to a greater extent. The internalized BGNs could activate the transcription factors RUNX2 and OSX, leading to the expression of osteogenesis-related genes. The results in the zebrafish osteoporosis model indicated that the presence of BGNs of higher CaO contents could enhance bone regeneration and rescue dexamethasone-induced osteoporosis to a greater extent. These findings demonstrate that BGNs can stimulate osteogenic differentiation of rBMSCs by releasing active ions or internalization. A higher CaO content facilitates osteogenesis and bone regeneration of zebrafish as well as relieving dexamethasone-induced osteoporosis. The zebrafish osteoporosis model can be a potent tool for evaluating the in vivo bone regeneration effects of bioactive materials. STATEMENT OF SIGNIFICANCE: Bioactive glass nanoparticles (BGNs) are increasingly used as fillers of nanocomposites or as delivery platforms of active ions to regenerate bone tissue. Various studies have shown that BGNs can enhance osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) by releasing active ions. However, the correlation between BGN composition and cellular responses and in vivo bone regeneration effect has still not been well investigated. Establishment of a suitable in vivo animal model for investigating this correlation is also challenging. The present study reports the influence of CaO content in binary SiO2-CaO BGNs on osteogenic differentiation of BMSCs extracellularly and intracellularly. This study also demonstrates the suitability of zebrafish osteoporosis model to investigate in vivo bone regeneration effect of BGNs.


Assuntos
Células-Tronco Mesenquimais , Nanopartículas , Osteoporose , Ratos , Animais , Osteogênese , Peixe-Zebra , Dióxido de Silício/farmacologia , Regeneração Óssea , Vidro , Diferenciação Celular , Células da Medula Óssea , Osteoporose/terapia , Osteoporose/metabolismo , Íons/farmacologia , Dexametasona/farmacologia , Células Cultivadas
19.
Braz J Microbiol ; 55(1): 629-637, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38110706

RESUMO

Antarctica has often been perceived as a pristine continent until the recent few decades as pollutants have been observed accruing in the Antarctic environment. Irresponsible human activities such as accidental oil spills, waste incineration and sewage disposal are among the primary anthropogenic sources of heavy metal contaminants in Antarctica. Natural sources including animal excrement, volcanism and geological weathering also contribute to the increase of heavy metals in the ecosystem. A microbial growth model is presented for the growth of a bacterial cell consortium used in the biodegradation of phenol in media containing different metal ions, namely arsenic (As), cadmium (Cd), aluminium (Al), nickel (Ni), silver (Ag), lead (Pb) and cobalt (Co). Bacterial growth was inhibited by these ions in the rank order of Al < As < Co < Pb < Ni < Cd < Ag. Greatest bacterial growth occurred in 1 ppm Al achieving an OD600 of 0.985 and lowest in 1 ppm Ag with an OD600 of 0.090. At a concentration of 1.0 ppm, Ag had a considerable effect on the bacterial consortium, inhibiting the degradation of phenol, whereas this concentration of the other metal ions tested had no effect on degradation. The biokinetic growth model developed supports the suitability of the bacterial consortium for use in phenol degradation.


Assuntos
Cádmio , Metais Pesados , Humanos , Animais , Cádmio/metabolismo , Ecossistema , Fenol/metabolismo , Regiões Antárticas , Chumbo/metabolismo , Metais Pesados/análise , Fenóis/farmacologia , Bactérias/metabolismo , Íons/metabolismo , Íons/farmacologia
20.
Acta Biomater ; 175: 382-394, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38160853

RESUMO

Conventional Ti-based implants are vulnerable to postsurgical infection and improving the antibacterial efficiency without compromising the osteogenic ability is one of the key issues in bone implant design. Although zinc oxide (ZnO) nanorods grown on Ti substrates hydrothermally can improve the antibacterial properties, but cannot meet the stringent requirements of bone implants, as rapid degradation of ZnO and uncontrolled leaching of Zn2+ are detrimental to peri-implant cells and tissues. To solve these problems, a lattice-damage-free method is adopted to modify the ZnO nanorods with thin calcium phosphate (CaP) shells. The Ca and P ions from the CaP shells diffuse thermally into the ZnO lattice to prevent the ZnO nanorods from rapid degradation and ensure the sustained release of Zn2+ ions as well. Furthermore, the designed heterostructural nanorods not only induce the osteogenic performances of MC3T3-E1 cells but also exhibit excellent antibacterial ability against S. aureus and E. coli bacteria via physical penetration. In vivo studies also reveal that hybrid Ti-ZnO@CaP5 can not only eradicates bacteria in contact, but also provides sufficient biocompatibility without causing excessive inflammation response. Our study provides insights into the design of multifunctional biomaterials for bone implants. STATEMENT OF SIGNIFICANCE: • A lattice-damage-free method is adopted to modify the ZnO nanorods with thin calcium phosphate (CaP) shells. • The dynamic process of Ca and P diffusion into the ZnO lattice is analyzed by experimental verification and theoretical calculation. • The degradation rate of ZnO nanorods is significantly decreased after CaP deposition. • The ZnO nanorods after CaP deposition can not only sterilize bacteria in contact via physical penetration, but also provide sufficient biocompatibility and osteogenic capability without causing excessive inflammation response..


Assuntos
Infecções Bacterianas , Óxido de Zinco , Humanos , Óxido de Zinco/farmacologia , Óxido de Zinco/química , Osteogênese , Cálcio/farmacologia , Titânio/farmacologia , Staphylococcus aureus , Escherichia coli , Antibacterianos/farmacologia , Antibacterianos/química , Bactérias , Fosfatos de Cálcio/farmacologia , Íons/farmacologia , Inflamação
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