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1.
Braz Oral Res ; 38: e028, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38597547

RESUMO

Acidic pH can modify the properties of repair cements. In this study, volumetric change and solubility of the ready-to-use bioceramic repair cement Bio-C Repair (BCR, Angelus, Londrina, PR, Brazil) were evaluated after immersion in phosphate-buffered saline (PBS) (pH 7.0) or butyric acid (pH 4.5). Solubility was determined by the difference in initial and final mass using polyethylene tubes measuring 4 mm high and 6.70 mm in internal diameter that were filled with BCR and immersed in 7.5 mL of PBS or butyric acid for 7 days. The volumetric change was established by using bovine dentin tubes measuring 4 mm long with an internal diameter of 1.5 mm. The dentin tubes were filled with BCR at 37°C for 24 hours. Scanning was performed with micro-computed tomography (micro-CT; SkyScan 1176, Bruker, Kontich, Belgium) with a voxel size of 8.74 µm. Then, the specimens were immersed in 1.5 mL of PBS or butyric acid at and 37 °C for 7 days. After this period, a new micro-CT scan was performed. Bio-C Repair showed greater mass loss after immersion in butyric acid when compared with immersion in PBS (p<0.05). Bio-C Repair showed volumetric loss after immersion in butyric acid and increase in volume after immersion in PBS (p<0.05). The acidic pH influenced the solubility and dimensional stability of the Bio-C Repair bioceramic cement, promoting a higher percentage of solubility and decrease in volumetric values.


Assuntos
Óxidos , Materiais Restauradores do Canal Radicular , Animais , Bovinos , Solubilidade , Óxidos/química , Compostos de Cálcio/química , Microtomografia por Raio-X , Ácido Butírico , Teste de Materiais , Cimentos Dentários/química , Cimentos de Ionômeros de Vidro , Concentração de Íons de Hidrogênio , Silicatos/química , Materiais Restauradores do Canal Radicular/química
2.
BMC Plant Biol ; 24(1): 288, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38627611

RESUMO

One of the major problems endangering plant growth and productivity worldwide is salt stress. This study aimed to assess the effects of potassium silicate (K2O3Si) on the physical, biochemical, and morphological characteristics of chicory (Cichorium intybus L.) under various levels of salinity stress. The plants were treated with K2O3Si at concentrations of 0, 1, 2, and 3 mM and cultivated under different salt stress conditions (0, 80, 160, and 240 mM NaCl). The findings revealed that salt stress led to decreased root and shoot dry weights, Fv/Fm ratio, chlorophyll a, b, and total chlorophyll, as well as inulin contents. However, foliar exposure to K2O3Si at all salinity levels resulted in improvements in the measured traits. As salinity levels increased, there was a corresponding increase in the accumulation of sodium ions (Na+) and a sharp reduction in potassium ions (K +) in the shoot. Nonetheless, treatment with K2O3Si caused a decrease in Na + accumulation and an improvement in K+ content under all salinity levels. Carotenoid content increased under 80 mM salinity stress, but decreased with higher salinity levels. Application of K2O3Si at all levels resulted in increased carotenoid content under salinity stress conditions. The content of MDA increased significantly with increasing salinity stress, particularly at 240 mM. However, foliar spraying with K2O3Si significantly decreased MDA content at all salinity levels. Salinity stress up to 160 mM increased the total phenol, flavonoid, and anthocyanin contents, while 240 mM NaCl decreased the biosynthesis of phytochemicals. Additionally, the use of K2O3Si increased the content of total phenol, flavonoid, and anthocyanin at all salt levels. Foliar application of K2O3Si increased the tolerance of chicory plants to salinity stress by reducing MDA and increasing phenolic compounds and potassium content. These results suggest that exogenous K2O3Si can be a practical strategy to improve the growth and yield of chicory plants exposed to saline environments.


Assuntos
Chicória , Clorofila A , Potássio , Antocianinas , Cloreto de Sódio , Estresse Salino , Antioxidantes , Íons , Silicatos , Compostos Fitoquímicos , Carotenoides , Fenóis , Salinidade , Estresse Fisiológico
3.
J Hazard Mater ; 470: 134190, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38593659

RESUMO

Organophosphorus compounds (OPs), such as VX, pose a significant threat due to their neurotoxic and hazardous properties. Skin decontamination is essential to avoid irreversible effects. Fuller's earth (FE), a phyllosilicate conventionally employed in powder form, has demonstrated decontamination capacity against OPs. The aim of this study was to develop a formulation that forms a film on the skin, with a significant OP removal capacity (>95 %) coupled with sequestration capabilities, favorable drying time and mechanical properties to allow for easy application and removal, particularly in emergency context. Various formulations were prepared using different concentrations of polyvinyl alcohol (PVA), FE and surfactants. Their removal and sequestration capacity was tested using paraoxon-ethyl (POX), a chemical that simulates the behavior of VX. Formulations with removal capacity levels surpassing 95 % were mechanically characterized and cell viability assays were performed on Normal Human Dermal Fibroblast (NHDF). The four most promising formulations were used to assess decontamination efficacy on pig ear skin explants. These formulations showed decontamination levels ranging from 84.4 ± 4.7 % to 96.5 ± 1.3 %, which is equivalent to current decontamination methods. These results suggest that this technology could be a novel and effective tool for skin decontamination following exposure to OPs.


Assuntos
Descontaminação , Paraoxon , Pele , Descontaminação/métodos , Animais , Pele/efeitos dos fármacos , Humanos , Suínos , Paraoxon/toxicidade , Paraoxon/química , Compostos de Alumínio/química , Sobrevivência Celular/efeitos dos fármacos , Silicatos/química , Álcool de Polivinil/química , Compostos de Magnésio/química , Compostos de Magnésio/farmacologia , Tensoativos/química , Fibroblastos/efeitos dos fármacos
4.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 42(2): 242-248, 2024 Apr 01.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-38597084

RESUMO

OBJECTIVES: This study aimed to observe the outcomes of iRoot BP Plus full pulpotomy in primary molars with partial irreversible pulpitis retrospectively. METHODS: Collect 102 cases of primary molars with partial irreversible pulpitis undergoing iRoot BP Plus full pulpotomy from January 2019 to August 2023, with a follow-up period of 24-47 months. Based on the presence of irreversible pulpitis symptoms before surgery, the included cases will be divided into asymptomatic group (n=53) and symptomatic group (n=49). Observe the clinical and imaging success rates of both groups. RESULTS: Clinical success rates were 96.2% and 97.9% in asymptomatic and symptomatic groups, and radiographic success rates were 96.2% and 93.9% respectively. CONCLUSIONS: iRoot BP Plus full pulpotomy can be used for the treatment of primary molars with partial irreversible pulpitis under an enhanced pulpotomy protocol.


Assuntos
Pulpite , Pulpotomia , Humanos , Pulpotomia/métodos , Pulpite/cirurgia , Pulpite/tratamento farmacológico , Estudos Retrospectivos , Silicatos/uso terapêutico , Dente Molar/cirurgia , Resultado do Tratamento , Compostos de Cálcio/uso terapêutico
5.
Trop Anim Health Prod ; 56(4): 130, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38635010

RESUMO

This study evaluated the possibilities of pumice (light stones) as litter material in broiler production. Experimental treatments included wood shavings (WS), acidic pumice (AP), and basic pumice (BP) alone, and in combination; wood shaving + acidic pumice (WSAP) and wood shaving + basic pumice (WSBP) in a ratio of 1:1. Two trials were performed, one in summer, and the other in winter. Each trial involved 750 mixed-sex Ross (308) broilers. Also, there were 15 replicate pens with 50 broilers and a stocking density of 12.5 birds/m2 for each pen at the beginning of each trial. Performance, litter quality, carcass parameters, body and leg abnormalities, body temperature, fear and stress responses, proportional asymmetry, and some behavior expressions were investigated. The litter treatment influenced the final live body weight, litter moisture, ammonia concentration, footpad dermatitis, hock burn, breast blister, hot carcass yield, heart, liver, spleen, abdominal fat, wing and neck ratio, breast and back cleanliness, and the expression of dust bathing and foraging behaviors (P < 0.01; P < 0.05). Furthermore, there was a seasonal effect on live body weight, feed conversion ratio, livability, litter pH, 42-day litter moisture, hot carcass yield, back cleanliness, footpad dermatitis, hock burn, footpad temperature, heterophil-to-lymphocyte ratio, and expression of pecking behavior (P < 0.01; P < 0.05). It is suggested that acidic pumice stone alone or in a mixture with wood shavings could be used as a reliable litter material, alternative to wood shavings.


Assuntos
Galinhas , Dermatite , Silicatos , Animais , Peso Corporal , Amônia , Dermatite/veterinária
6.
BMC Oral Health ; 24(1): 476, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38643094

RESUMO

OBJECTIVES: This study aimed to design a modified passive-deflation sealer injection needle and investigate its ability to improve obturation quality of single-cone technique through assessing the distribution of voids in root canals using micro-computed tomography (micro-CT). MATERIALS AND METHODS: Forty-eight mandibular incisors were divided into eight groups (n = 6), according to the taper of root canal preparation (0.06 or 0.04), the needle used for sealer injection (modified or commercial iRoot SP injection needle), and the obturation method (iRoot SP sealer-only or single-cone obturation). After obturation, each specimen was scanned by micro-CT. The volumetric percentage and distribution of all voids were first analyzed and compared among groups, then the open and closed voids were separately analyzed and compared among single-cone obturation groups. RESULTS: Compared to commercial needle groups, modified needle groups showed much less voids, especially in the apical root canal part (P < 0.05). Besides, the modified needle groups produced much less open voids than commercial needle groups despite the root canal taper (P < 0.05). CONCLUSIONS: The modified passive deflation sealer injection needle could effectively improve the quality of single-cone obturation through reducing intra-canal voids, especially open voids throughout the root canal, thus might possibly be developed as an effective intra-canal sealer delivering instrument.


Assuntos
Cavidade Pulpar , Materiais Restauradores do Canal Radicular , Silicatos , Humanos , Microtomografia por Raio-X , Cavidade Pulpar/diagnóstico por imagem , Obturação do Canal Radicular/métodos , Preparo de Canal Radicular/métodos , Guta-Percha
7.
Sci Rep ; 14(1): 6716, 2024 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-38509345

RESUMO

Cement is the most widely used construction material due to its strength and affordability, but its production is energy intensive. Thus, the need to replace cement with widely available waste material such as incinerated black filter cake (IBFC) in order to reduce energy consumption and the associated CO2 emissions. However, because IBFC is a newly discovered cement replacement material, several parameters affecting the mechanical properties of IBFC-cement composite have not been thoroughly investigated yet. Thus, this work aims to investigate the impact of IBFC as a cement replacement and the addition of the calcifying bacterium Lysinibacillus sp. WH on the mechanical and self-healing properties of IBFC cement pastes. The properties of the IBFC-cement pastes were assessed by determining compressive strength, permeable void, water absorption, cement hydration product, and self-healing property. Increases in IBFC replacement reduced the durability of the cement pastes. The addition of the strain WH to IBFC cement pastes, resulting in biocement, increased the strength of the IBFC-cement composite. A 20% IBFC cement-replacement was determined to be the ideal ratio for producing biocement in this study, with a lower void percentage and water absorption value. Adding strain WH decreases pore sizes, densifies the matrix in ≤ 20% IBFC biocement, and enhances the formation of calcium silicate hydrate (C-S-H) and AFm ettringite phases. Biogenic CaCO3 and C-S-H significantly increase IBFC composite strength, especially at ≤ 20% IBFC replacement. Moreover, IBFC-cement composites with strain WH exhibit self-healing properties, with bacteria precipitating CaCO3 crystals to bridge cracks within two weeks. Overall, this work provides an approach to produce a "green/sustainable" cement using biologically enabled self-healing characteristics.


Assuntos
Saccharum , Silicatos , Compostos de Cálcio , Cimentos Ósseos , Bactérias , Água
8.
Sci Rep ; 14(1): 6395, 2024 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-38493190

RESUMO

To evaluate the success of pulpotomy in treating immature permanent teeth with irreversible pulpitis. This case series included patients with irreversible pulpitis admitted to the Department of Oral Medicine at the author's Hospital between 2015 and 2020. The pulpotomies were carried out by clinicians with > 5 years of working experience. The follow-up findings and radiographic images were reviewed by two attending dentists. This study included 49 teeth from 48 children (25 boys and 23 girls). The follow-up was 23.3 ± 6.8 months (from 12 to 40 months). The success rate of pulpotomy was 85.7% (42/49). Pulpotomy failed in seven teeth (14.3%). The treatment success rate for traumatic crown fracture was lower than for dental caries and dens evaginatus (P < 0.001). There were no significant differences in the success rate of the pulp-capping agent, tooth root developmental phase, and pulpotomy method (all P > 0.05). Pulpotomy might be successfully used to treat immature permanent teeth with irreversible pulpitis in young patients mainly caused by caries and a fractured tubercle of dens evaginatus.


Assuntos
Cárie Dentária , Fraturas Ósseas , Pulpite , Masculino , Criança , Feminino , Humanos , Pulpotomia/métodos , Pulpite/cirurgia , Compostos de Cálcio , Estudos Retrospectivos , Silicatos , Compostos de Alumínio , Óxidos , Resultado do Tratamento
9.
Phys Med Biol ; 69(7)2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38529716

RESUMO

Objective. Lutetium yttrium oxyorthosilicate (LYSO) scintillation crystals are used in positron emission tomography (PET) due to their high gamma attenuation, fair energy resolution, and fast scintillation decay time. The enduring presence of the176Lu isotope, characterized by a half-life of 37.9 billion years, imparts a consistent radiation background (BG) profile that depends on the geometry and composition attributes of the LYSO crystals.Approach. In this work, we proposed a methodology for estimating the composition of LYSO crystals in cases where the exact Lutetium composition remains unknown. The connection between BG spectrum intensity and intrinsic radioactivity enables precise estimation of Lutetium density in LYSO crystal samples. This methodology was initially applied to a well-characterized LYSO crystal sample, yielding results closely aligned with the known composition. The composition estimation approach was extended to several samples of undisclosed LYSO crystals, encompassing single crystal and crystal array configurations. Furthermore, we model the background spectrum observed in the LYSO-based detector and validate the observed spectra via simulations.Main results. The estimated Lutetium composition exhibited adequate consistency across different samples of the same LYSO material, with variations of less than 1%. The result of the proposed approach coupled with the simulation successfully models the background radiation spectra in various LYSO-based detector geometries.Significance. The implications of this work extend to the predictive assessment of system behaviors and the autonomous configuration parameters governing LYSO-based detectors.


Assuntos
Lutécio , Ítrio , Lutécio/química , Tomografia por Emissão de Pósitrons/métodos , Silicatos/química
10.
PLoS One ; 19(3): e0295031, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38536835

RESUMO

Addressing soil nutrient degradation and global warming requires novel solutions. Enhanced weathering using crushed basalt rock is a promising dual-action strategy that can enhance soil health and sequester carbon dioxide. This study examines the short-term effects of basalt amendment on spring oat (Avena sativa L.) during the 2022 growing season in NE England. The experimental design consisted of four blocks with control and basalt-amended plots, and two cultivation types within each treatment, laid out in a split plot design. Basalt (18.86 tonnes ha-1) was incorporated into the soil during seeding. Tissue, grain and soil samples were collected for yield, nutrient, and pH analysis. Basalt amendment led to significantly higher yields, averaging 20.5% and 9.3% increases in direct drill and ploughed plots, respectively. Soil pH was significantly higher 256 days after rock application across cultivation types (direct drill: on average 6.47 vs. 6.76 and ploughed: on average 6.69 vs. 6.89, for control and basalt-amended plots, respectively), likely due to rapidly dissolving minerals in the applied basalt, such as calcite. Indications of growing season differences in soil pH are observed through direct measurement of lower manganese and iron uptake in plants grown on basalt-amended soil. Higher grain and tissue potassium, and tissue calcium uptake were observed in basalt-treated crops. Notably, no accumulation of potentially toxic elements (arsenic, cadmium, chromium, nickel) was detected in the grain, indicating that crops grown using this basaltic feedstock are safe for consumption. This study indicates that basalt amendments can improve agronomic performance in sandy clay-loam agricultural soil under temperate climate conditions. These findings offer valuable insights for producers in temperate regions who are considering using such amendments, demonstrating the potential for improved crop yields and environmental benefits while ensuring crop safety.


Assuntos
Agricultura , Avena , Silicatos , Estações do Ano , Solo , Grão Comestível , Produtos Agrícolas
11.
Dent Mater J ; 43(2): 276-285, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38447980

RESUMO

Premixed calcium silicate cements (pCSCs) contain vehicles which endow fluidity and viscosity to CSCs. This study aimed to investigate the effects of three vehicles, namely, polyethylene glycol (PEG), propylene glycol (PG), and dimethyl sulfoxide (DMSO), on the physicochemical properties and biocompatibility of pCSCs. The setting time, solubility, expansion rate, and mechanical strength of the pCSCs were evaluated, and the formation of calcium phosphate precipitates was assessed in phosphate-buffered saline (PBS). The effects of pCSC extracts on the osteogenic differentiation of mesenchymal stem cells (MSCs) were investigated. Finally, the tissue compatibility of pCSCs in rat femurs was observed. CSC containing PEG (CSC-PEG) exhibited higher solubility and setting time, and CSC-DMSO showed the highest expansion rate and mechanical strength. All pCSCs generated calcium phosphate precipitates. The extract of CSC-PG induced the highest expressions of osteogenic markers along with the greatest calcium deposites. When implanted in rat femurs, CSC-PEG was absorbed considerably, whereas CSC-PG remained relatively unaltered inside the femur.


Assuntos
Dimetil Sulfóxido , Osteogênese , Teste de Materiais , Compostos de Cálcio/farmacologia , Compostos de Cálcio/química , Fosfatos de Cálcio/farmacologia , Fosfatos de Cálcio/química , Silicatos/farmacologia , Silicatos/química , Cálcio , Cimento de Silicato/química , Cimentos Dentários/farmacologia , Cimentos Dentários/química
12.
Sci Total Environ ; 925: 171762, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38508270

RESUMO

Ores serve as energy and nutrient sources for microorganisms. Through complex biochemical processes, microorganisms disrupt the surface structure of ores and release metal elements. However, there is limited research on the mechanisms by which bacteria with different nutritional modes act during the leaching process of different crystal structure ores. This study evaluated the leaching efficiency of two types of bacteria with different nutritional modes, heterotrophic bacterium Bacillus mucilaginosus (BM) and autotrophic bacterium Acidithiobacillus ferrooxidans (AF), on different crystal structure lithium silicate ores (chain spodumene, layered lepidolite and ring elbaite). The aim was to understand the behavioral differences and decomposition mechanisms of bacteria with different nutritional modes in the process of breaking down distorted crystal lattices of ores. The results revealed that heterotrophic bacterium BM primarily relied on passive processes such as bacterial adsorption, organic acid corrosion, and the complexation of small organic acids and large molecular polymers with metal ions. Autotrophic bacterium AF, in addition to exhibiting stronger passive processes such as organic acid corrosion and complexation, also utilized an active transfer process on the cell surface to oxidize Fe2+ in the ores for energy maintenance and intensified the destruction of ore lattices. As a result, strain AF exhibited a greater leaching effect on the ores compared to strain BM. Regarding the three crystal structure ores, their different stacking modes and proportions of elements led to significant differences in structural stability, with the leaching effect being highest for layered structure, followed by chain structure, and then ring structure. These findings indicate that bacteria with different nutritional modes exhibit distinct physiological behaviors related to their nutritional and energy requirements, ultimately resulting in different sequences and mechanisms of metal ion release from ores after lattice damage.


Assuntos
Acidithiobacillus , Bactérias , Lítio , Bactérias/metabolismo , Metais/metabolismo , Silicatos/química , Íons
13.
Sci Total Environ ; 925: 171825, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38513852

RESUMO

Carbon dioxide (CO2) is a primary greenhouse gas that has experienced a surge in atmospheric concentration due to human activities and lifestyles. It is imperative to curtail atmospheric CO2 levels promptly to alleviate the multifaceted impacts of climate warming. The soil serves as a natural reservoir for CO2 sequestration. The scientific premise of this study is that CO2 sequestration in agriculturally relevant, organically-deficient saline soil can be achieved by incorporating alkaline earth silicates. Volcanic ash (VA) was used as a soil amendment for CO2 removal from saline soil by leveraging enhanced silicate rock weathering (ERW). The study pursued two primary objectives: first, we aimed to evaluate the impact of various doses of VA, employed as an amendment for organically-deficient soil, on the growth performance of key cultivated crops (sorghum and mung bean) in inland saline-alkaline agricultural regions of northeastern China. Second, we aimed to assess alterations in the physical properties of the amended soil through mineralogical examinations, utilizing X-ray diffraction (XRD) and scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM-EDS) analyses, quantifying the increase in inorganic carbon content within the soil. In the potting tests, mung bean plant height exhibited a noteworthy increase of approximately 41 % with the addition of 10 % VA. Sorghum plant height and aboveground and belowground biomass dry weights increased with VA application across all tested doses. At the optimal VA application rate (20 %), the sorghum achieved a CO2 sequestration rate of 0.14 kg CO2·m-2·month-1. XRD and SEM-EDS analyses confirmed that the augmented inorganic carbon in the VA-amended soils stemmed primarily from calcite accumulation. These findings contribute to elucidating the mechanism underlying VA as an amendment for organically-deficient soils and provide an effective approach for enhancing the carbon sink capacity of saline soils.


Assuntos
Solo , Sorghum , Humanos , Solo/química , Dióxido de Carbono/análise , Erupções Vulcânicas , Agricultura , Tempo (Meteorologia) , Grão Comestível/química , Sequestro de Carbono , Silicatos
14.
J Clin Pediatr Dent ; 48(2): 93-101, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38548638

RESUMO

When dental pulp is exposed, it must be covered with a biocompatible material to form reparative dentine. The material used, besides being biocompatible, should have an ideal surface structure for the attachment, proliferation and differentiation of dental pulp stem cells. This study aimed to evaluate the porosity of the microstructures of four pulp capping materials using micro-computed tomography (micro-CT). Biodentine, Bioaggregate, TheraCal and Dycal materials were prepared according to the manufacturer's instructions using 2 × 9 mm Teflon molds. A total of 60 samples, 15 in each group, were scanned using micro-CT. Open and closed pores and the total porosity of the microstructures of the materials were assessed. The findings obtained from the study were analyzed via the Kruskal-Wallis test followed by the Mann-Whitney U test. The porosity of Bioaggregate was significantly higher than that of Biodentine, Dycal and TheraCal in all porosity values. While Biodentine did not show a statistically significant difference in open and total porosity values from either TheraCal or Dycal, closed porosity values of Dycal were significantly higher than those of Biodentine and TheraCal. Because of the affinity of cells to porous surfaces, the pulp capping materials' microstructure may affect the pulp capping treatment's success. From this perspective, the use of Bioaggregate in direct pulp capping may increase the success of treatment.


Assuntos
Hidróxido de Cálcio , Capeamento da Polpa Dentária , Hidroxiapatitas , Minerais , Agentes de Capeamento da Polpa Dentária e Pulpectomia , Humanos , Capeamento da Polpa Dentária/métodos , Microtomografia por Raio-X , Porosidade , Óxidos/química , Agentes de Capeamento da Polpa Dentária e Pulpectomia/uso terapêutico , Silicatos/química , Compostos de Cálcio/química , Combinação de Medicamentos , Compostos de Alumínio/química
15.
Biomed Mater ; 19(3)2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38518361

RESUMO

Rapid bone regeneration in implants is important for successful transplantation. In this regard, we report the development of calcium silicate/zinc silicate (CS/ZS) dual-compound-incorporated calcium phosphate cement (CPC) scaffolds with a three-dimensional poly (lactic-co-glycolic acid) network that synergistically promote bone regeneration.In vitroresults demonstrated that the incorporation of CS/ZS dual compounds into the CPC significantly promoted the osteogenic differentiation of stem cells compared to the addition of CS or ZS alone. Moreover, the bone-regeneration efficacy of the composite scaffolds was validated by filling in femur condyle defects in rabbits, which showed that the scaffolds with CS and ZS possessed a great bone repair effect, as evidenced by more new bone formation and a faster scaffold biodegradation compared to the scaffold with CS alone.


Assuntos
Células-Tronco Mesenquimais , Osteogênese , Compostos de Zinco , Animais , Coelhos , Tecidos Suporte , Zinco/farmacologia , Proliferação de Células , Compostos de Cálcio , Regeneração Óssea , Silicatos , Fosfatos de Cálcio/farmacologia
16.
Nephrology (Carlton) ; 29(5): 278-287, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38443742

RESUMO

INTRODUCTION: Hyperkalaemia (HK) is prevalent among patients with chronic kidney disease (CKD) and chronic heart failure, especially if they are treated with renin-angiotensin-aldosterone system inhibitors (RAASi). This study evaluated the cost-effectiveness of a newly developed anti-HK therapy, sodium zirconium cyclosilicate (SZC), to the current standard of care for treating HK in advanced CKD patients from the Singapore health system perspective. METHODS: We adapted a global microsimulation model to simulate individual patients' potassium level trajectories with baseline potassium ≥5.5 mmol/L, CKD progression, changes in treatment, and other fatal and non-fatal events. Effectiveness data was derived from ZS-004 and ZS-005 trials. Model parameters were localised using CKD patients' administrative and medical records at the Singapore General Hospital Department of Renal Medicine. We estimated the lifetime cost and quality-adjusted life years (QALYs) of each HK treatment, and the incremental cost-effectiveness ratio of SZC. RESULTS: SZC demonstrated cost-effectiveness with an incremental cost-effectiveness ratsio of SGD 45 068 per QALY over a lifetime horizon, below the willingness-to-pay threshold of SGD 90 000 per QALY. Notably, SZC proved most cost-effective for patients with less severe CKD who were concurrently using RAASi. Sensitivity analyses confirmed the robustness of the findings, accounting for alternative parameter values and statistical uncertainty. CONCLUSION: This study establishes the cost-effectiveness of SZC as a treatment for HK, highlighting its potential to mitigate the risk of hyperkalaemia and optimise RAASi therapy. These findings emphasise the value of integrating SZC into the Singapore health system for improved patient outcomes and resource allocation.


Assuntos
Glomerulonefrite , Hiperpotassemia , Insuficiência Renal Crônica , Silicatos , Humanos , Hiperpotassemia/tratamento farmacológico , Análise Custo-Benefício , Singapura/epidemiologia , Potássio , Doença Crônica , Insuficiência Renal Crônica/diagnóstico , Insuficiência Renal Crônica/tratamento farmacológico , Rim
17.
J Hazard Mater ; 469: 133994, 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38503210

RESUMO

The efficient remediation of the soil co-contaminated with heavy metals and polybrominated diphenyl ethers (PBDEs) from electronic disassembly zones is a new challenge. Here, we screened a fungus of F. solani (F.s) can immobilize Cd and remove PBDEs. wIt combined with tourmaline enhances the remediation of co- pollutants in the soil. Furthermore, the environment risks of the enhanced technology were assessed through the amount of Cd/BDE-153 in Amaranthus tricolor L. (amaranth) migrated from soil, as well as the changes of soil microorganism communities and enzyme activities. The results showed the combined treatment of tourmaline and F.s made the removal percentage of BDE-153 in rhizosphere soil co-contaminated with BDE-153 and Cd reached 46.5%. And the weak acid extractable Cd in rhizosphere soil decreased by 33.7% compared to control group. In addition, the combined remediation technology resulted in a 32.5% (22.8%), 45.5% (37.2%), and 50.7% (38.1%) decrease in BDE-153 (Cd) content in the roots, stems, and leaves of amaranth, respectively. Tourmaline combined with F.s can significantly increase soil microorganism diversity, soil dehydrogenase and urease activities, further improving the remediation rate of Cd and BDE-153co-pollutants in soil and the biomass of amaranth. This study provides the remediation technology of soil co-contaminated with heavy metal and PBDEs and ensure the maintenance of food security.


Assuntos
Amaranthus , Poluentes Ambientais , Metais Pesados , Bifenil Polibromatos , Silicatos , Poluentes do Solo , Solo , Cádmio , Biodegradação Ambiental , Éteres Difenil Halogenados/análise , Poluentes do Solo/análise , Metais Pesados/análise
18.
Environ Monit Assess ; 196(4): 389, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38512521

RESUMO

To test the serial discontinuity concept (SDC) predictions in a regulated river ecosystem, environmental parameters and phytoplankton community structure were determined in a subtropical river (China) which was regulated by 11 cascade dams. Our results showed that total phosphorus (TP) and silicate during the wet period in several dams supported the SDC predictions. Variations of phytoplankton species composition in several cascade dams, such as Datengxia (DTX) and Changzhou (CZ), also supported the SDC predictions. Moreover, the stations near the dams showed the maximum or minimum values of total species numbers in each cascade segment. Predictive model indicated that the types of phytoplankton decreased in the middle reaches, conforming to SDC predictions. In the whole system of cascading dams, an increase in silicate concentration and phytoplankton communities in the downstream was also consistent with SDC predictions. Therefore, these findings aligned with the SDC predictions in the aspects of both single dam and whole cascade dam system to some extent. In future research, our aim is to further investigate the effects of cascade damming on additional phytoplankton-related indices in this aquatic ecosystem. We hope to gather more comprehensive data to fully validate the SDC predictions.


Assuntos
Ecossistema , Fitoplâncton , Biomarcadores Ambientais , Monitoramento Ambiental , China , Silicatos
19.
BMC Oral Health ; 24(1): 335, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38486235

RESUMO

BACKGROUND: Several efforts have been made to improve mechanical and biological properties of calcium silicate-based cements through changes in chemical composition of the materials. This study aimed to investigate the physical (including setting time and compressive strength) and chemical (including calcium ion release, pH level) properties as well as changes in cytotoxicity of mineral trioxide aggregate (MTA) after the addition of 3 substances including CaCl2, Na2HPO4, and propylene glycol (PG). METHODS: The systematic review was conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Electronic searches were performed on PubMed, Embase, and Scopus databases, spanning from 1993 to October 2023 in addition to manual searches. Relevant laboratory studies were included. The quality of the included studies was assessed using modified ARRIVE criteria. Meta-analyses were performed by RevMan statistical software. RESULTS: From the total of 267 studies, 24 articles were included in this review. The results of the meta-analysis indicated that addition of PG increased final setting time and Ca2+ ion release. Addition of Na2HPO4 did not change pH and cytotoxicity but reduced the final setting time. Incorporation of 5% CaCl2 reduced the setting time but did not alter the cytotoxicity of the cement. However, addition of 10% CaCl2 reduced cell viability, setting time, and compressive strength. CONCLUSION: Inclusion of 2.5% wt. Na2HPO4 and 5% CaCl2 in MTA can be advisable for enhancing the physical, chemical, and cytotoxic characteristics of the admixture. Conversely, caution is advised against incorporating elevated concentrations of PG due to its retarding effect. TRIAL REGISTRATION: PROSPERO registration number: CRD42021253707.


Assuntos
Compostos de Alumínio , Compostos de Cálcio , Óxidos , Silicatos , Compostos de Alumínio/toxicidade , Compostos de Alumínio/química , Cloreto de Cálcio/farmacologia , Cimentos Dentários/toxicidade , Cimentos Dentários/química , Combinação de Medicamentos , Óxidos/toxicidade , Óxidos/química , Propilenoglicol/química
20.
PLoS One ; 19(3): e0298661, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38512829

RESUMO

The selective separation of ions from aqueous systems, and even in the human body, is a crucial to overall environmental management and health. Nanoporous materials are widely known for their selective removal of cations from aqueous media, and therefore have been targeted for use as a pharmaceutical to treat hyperkalemia. This study investigated the detailed crystallographic molecular mechanisms that control the potassium ion selectivity in the nanoporous cubic zirconium silicate (CZS) related materials. Using time-resolved in situ Raman spectroscopy and time-resolved in situ X-ray diffraction, the selectivity mechanisms were determined to involve a synchronous cation-cation repulsion process that serves to open a favorable coordination bonding environment for potassium, not unlike the ion selectivity filter process found in potassium ion channels in proteins. Enhancement of ion exchange was observed when the CZS material was in a partial protonated state (≈3:1 Na:H), causing an expansion of the unit-cell volume, enlargement of the 7 member-ring window, and distortion of framework polyhedra, which allowed increased accessibility to the cage structures and resulted in rapid irreversible potassium ion exchange.


Assuntos
Potássio , Prótons , Silicatos , Humanos , Potássio/metabolismo , Hidrogênio , Troca Iônica , Cátions , Zircônio/química , Preparações Farmacêuticas
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