Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 997
Filtrar
Mais filtros

Medicinas Complementares
Intervalo de ano de publicação
1.
Zhongguo Zhong Yao Za Zhi ; 49(4): 853-857, 2024 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-38621892

RESUMO

Gypsum Fibrosum, as a classic heat-clearing medicine, is widely used in the clinical practice of traditional Chinese medicine(TCM). However, debates exist about the material basis and mechanism of its efficacy. Therefore, this paper reviewed the recent research progress in the heat-clearing effect and mechanism of Gypsum Fibrosum and discussed the material basis for the heat-clearing effect of this medicine. Ca~(2+) may inhibit the upward movement of temperature set point by regulating the Na~+/Ca~(2+) level in the heat-regulating center. Moreover, trace elements may inhibit the rise of body temperature by regulating the immune system, promoting the absorption of Ca~(2+), and affecting the synthesis of prostaglandin E2(PGE2). This review aims to enrich the knowledge about the mechanism of Gypsum Fibrosum in clearing heat and provides a scientific basis for the clinical application and further development of Gypsum Fibrosum.


Assuntos
Medicamentos de Ervas Chinesas , Medicamentos de Ervas Chinesas/farmacologia , Sulfato de Cálcio/farmacologia , Temperatura Alta , Medicina Tradicional Chinesa
2.
Molecules ; 29(6)2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38542902

RESUMO

The extraction of rare earth elements (REEs) from phosphogypsum (PG) is of great significance for the effective utilization of rare earth resources and enhancing the resource value of PG waste residues. This study used Aspergillus niger (A. niger) fungal culture filtrate as a leaching agent to investigate the behavior of extracting REEs from PG through direct and indirect contact methods. According to the ICP-MS results, direct leaching at a temperature of 30 °C, shaking speed of 150 rpm, and a solid-liquid ratio of 2:1, achieved an extraction rate of 74% for REEs, with the main elements being yttrium (Y), lanthanum (La), cerium (Ce), and neodymium (Nd). Under the same conditions, the extraction rate of REEs from phosphogypsum using an A. niger culture filtrate was 63.3% higher than that using the simulated organic acid-mixed solution prepared with the main organic acid components in the A. niger leachate. Moreover, the morphological changes observed in A. niger before and after leaching further suggest the direct involvement of A. niger's metabolic process in the extraction of REEs. When compared to using organic acids, A. niger culture filtrate exhibits higher leaching efficiency for extracting REEs from PG. Additionally, using A. niger culture filtrate is a more environmentally friendly method with the potential for industrial-scale applications than using inorganic acids for the leaching of REEs from PG.


Assuntos
Aspergillus niger , Metais Terras Raras , Fósforo , Lantânio , Sulfato de Cálcio
3.
J Environ Manage ; 357: 120706, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38554456

RESUMO

Amending agricultural fields with gypsum has been proposed as a cost-effective measure to reduce P load on coastal waters. We treated 1490 ha of clayey fields with phosphogypsum (4 t ha-1) in Southwest Finland and monitored the recipient river with online sensors and water sampling for the preceding spring and 5 years after the amendment. Gypsum immediately decreased the riverine fluxes, the effect lasting at least 5 years for particulate P (PP), total suspended solids (TSS), and dissolved organic C (DOC) and 1-2 years for dissolved reactive P (DRP). Compared with an upstream control area, the fluxes of PP, TSS, and DOC decreased by 15%, 25%, and 8.9%, respectively, as a 5-year average. Assuming the change in the fluxes occurred only due to gypsum, the amended fields showed 35%, 59%, and 64% lower losses for PP, TSS, and DOC than the unamended ones. More than half of the gypsum remained in the soil even after 5 years; thus, although the efficiency of gypsum lessened over time, its residual effect may be present. However, the difference in the erodibility between the control and treatment areas impacted the validity of the results, especially as the pre-gypsum period was short. In addition, the performance of gypsum showed spatial variation.


Assuntos
Sulfato de Cálcio , Solo , Fósforo , Argila , Estações do Ano
4.
Sci Total Environ ; 926: 172018, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38547988

RESUMO

The improper disposal of large amounts of phosphogypsum generated during the production process of the phosphorus chemical industry (PCI) still exists. The leachate formed by phosphogypsum stockpiles could pose a threat to the ecological environment and human health. Nevertheless, information regarding the harmful effects of phosphogypsum leachate on organisms is still limited. Herein, the physicochemical characteristics of phosphogypsum leachate were analyzed, and its toxicity effect on zebrafish (Danio rerio), particularly in terms of hepatotoxicity and potential mechanisms, were evaluated. The results indicated that P, NH3-N, TN, F-, As, Cd, Cr, Co, Ni, Zn, Mn, and Hg of phosphogypsum leachate exceeded the V class of surface water environmental quality standards (GB 3838-2002) to varying degrees. Acute toxicity test showed that the 96 h LC50 values of phosphogypsum leachate to zebrafish was 2.08 %. Under exposure to phosphogypsum leachate, zebrafish exhibited concentration-dependent liver damage, characterized by vacuolization and infiltration of inflammatory cells. The increased in Malondialdehyde (MDA) content and altered activities of antioxidant enzymes in the liver indicated the induction of oxidative stress and oxidative damage. The expression of apoptosis-related genes (P53, PUMA, Caspase3, Bcl-2, and Bax) were up-regulated at low dosage group and down-regulated at medium and high dosage groups, suggesting the occurrence of hepatocyte apoptosis or necrosis. Additionally, phosphogypsum leachate influenced the composition of the zebrafish gut microbiota by reducing the relative abundance of Bacteroidota, Aeromonas, Flavobacterium, Vibrio, and increasing that of Rhodobacter and Pirellula. Correlation analysis revealed that gut microbiota dysbiosis was associated with phosphogypsum leachate-induced hepatotoxicity. Altogether, exposure to phosphogypsum leachate caused liver damage in zebrafish, likely through oxidative stress and apoptosis, with the intestinal flora also playing a significant role. These findings contribute to understanding the ecological toxicity of phosphogypsum leachate and promote the sustainable development of PCI.


Assuntos
Sulfato de Cálcio , Doença Hepática Induzida por Substâncias e Drogas , Poluentes Químicos da Água , Animais , Humanos , Peixe-Zebra/metabolismo , Estresse Oxidativo , Fósforo/metabolismo , Poluentes Químicos da Água/metabolismo
5.
Chemosphere ; 355: 141818, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38548085

RESUMO

Skeleton builders were normally deemed to improve the high porosity and newly-generated permeability of sludge cakes by building water transfer channel during high pressure filtration, thus enhancing sludge dewaterability. However, currently a direct visualization proof of water transfer channel was still lacking. This study provided the direct proof for visualizing water transfer channel in dewatered sludge cakes conditioned with a typical skeleton builder (i.e., phosphogypsum (PG)) by X-ray micro-computed tomography (micro-CT) for the first time. After the addition of PG, the pixel value and image luminance increased significantly, indicating the presence of high density substances from both two-dimensional (2D) cross section and three-dimensional (3D) reconstruction CT images. Moreover, the CT numbers showed strong and negative correlations with specific resistance to filtration (SRF) (R = - 0.99, p < 0.05), capillary suction time (CST) (regression coefficient (R) = - 0.87, probability (p) < 0.05), and water content of the dewatered sludge cake (R = - 0.99, p < 0.05), respectively. These results indicated that the X-ray micro-CT could be a potential technique for analyzing the water distribution in sludge samples conditioned with skeleton builders.


Assuntos
Sulfato de Cálcio , Filtração , Fósforo , Esgotos , Microtomografia por Raio-X , Água , Esqueleto , Eliminação de Resíduos Líquidos/métodos
6.
J Environ Qual ; 53(3): 314-326, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38453693

RESUMO

Snowmelt runoff is a dominant pathway of phosphorus (P) losses from agricultural lands in cold climatic regions. Soil amendments effectively reduce P losses from soils by converting P to less soluble forms; however, changes in P speciation in cold climatic regions with fall-applied amendments have not been investigated. This study evaluated P composition in soils from a manured field with fall-amended alum (Al2(SO4)3·18H2O), gypsum (CaSO4·2H2O), or Epsom salt (MgSO4·7H2O) using three complementary methods: sequential P fractionation, scanning electron microscopy with energy-dispersive X-rays (SEM-EDX) spectroscopy, and P K-edge X-ray absorption near-edge structure spectroscopy (XANES). Plots were established in an annual crop field in southern Manitoba, Canada, with unamended and amended (2.5 Mg ha-1) treatments having four replicates in 2020 fall. Soil samples (0-10 cm) taken from each plot soon after spring snowmelt in 2021 were subjected to P fractionation. A composite soil sample for each treatment was analyzed using SEM-EDX and XANES. Alum- and Epsom salt-treated soils had significantly greater residual P fraction with a higher proportion of apatite-like P and a correspondingly lower proportion of P sorbed to calcite (CaCO3) than unamended and gypsum-amended soils. Backscattered electron imaging of SEM-EDX revealed that alum- and Epsom salt-amended treatments had P-enriched microsites frequently associated with aluminum (Al), iron (Fe), magnesium (Mg), and calcium (Ca), which was not observed in other treatments. Induced precipitation of apatite-like species may have been responsible for reduced P loss to snowmelt previously reported with fall application of amendments.


Assuntos
Compostos de Alúmen , Sulfato de Cálcio , Fósforo , Solo , Sulfato de Cálcio/química , Sulfato de Cálcio/análise , Solo/química , Fósforo/análise , Fósforo/química , Compostos de Alúmen/química , Fertilizantes/análise , Esterco/análise , Agricultura/métodos
7.
J Shoulder Elbow Surg ; 33(7): 1457-1464, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38417732

RESUMO

BACKGROUND: Periprosthetic joint infections (PJI) of the shoulder are a devastating complication of shoulder arthroplasty and are commonly caused by Staphylococcus and Cutibacterium acnes. Absorbable calcium sulfate (CS) beads are sometimes used for delivering antibiotics in PJI. This study evaluates the in vitro effect of different combinations of gentamicin, vancomycin, and ertapenem in beads made from CS cement on the growth of C acnes and coagulase-negative Staphylococcus (CNS) strains. METHODS: Three strains of C acnes and 5 strains of CNS from clinically proven shoulder PJI were cultured and plated with CS beads containing combinations of vancomycin, gentamicin, and ertapenem. Plates with C acnes were incubated anaerobically while plates with Staphylococcus were incubated aerobically at 37 °C. Zones of inhibition were measured at intervals of 3 and 7 days using a modified Kirby Bauer technique, and beads were moved to plates containing freshly streaked bacteria every seventh day. This process was run in triplicate over the course of 56 days. Statistical analysis was conducted using SPSS v. 28 with repeated measures analysis of variance (ANOVA) and pairwise comparisons with Tukey correction. RESULTS: In experiments with C acnes, beads containing ertapenem + vancomycin and vancomycin alone formed the largest zones of inhibition over time (P < .001). In experiments with Staphylococcus, beads containing vancomycin alone formed the largest zones of inhibition over time for all 5 strains (P < .001). Zones of inhibition were 1.4x larger for C acnes than for Staphylococcus with beads containing vancomycin alone. For both C acnes and Staphylococcus, beads containing ertapenem had the strongest initial effect, preventing all bacterial growth in C acnes and almost all growth for Staphylococcus during the first week but dropping substantially by the second week. Beads containing gentamicin alone consistently created smaller zones of inhibition than beads containing vancomycin alone, with vancomycin producing zones 5.3x larger than gentamicin in C acnes and 1.3x larger in Staphylococcus (P < .001). DISCUSSION: These data suggest that for both C acnes and Staphylococcal species, CS beads impregnated with vancomycin were most effective at producing a robust antibiotic effect. Additionally, ertapenem may be a viable supplement in order to create a more potent initial antibiotic effect but is not as effective as vancomycin when used alone. Gentamicin alone was not effective in maintaining consistent and long-term antibiotic effects. These results indicate that amongst the antibiotics currently commercially available to be used with CS, vancomycin is consistently superior to gentamicin in the setting of C. acnes and CNS.


Assuntos
Antibacterianos , Cimentos Ósseos , Sulfato de Cálcio , Propionibacterium acnes , Infecções Relacionadas à Prótese , Staphylococcus , Vancomicina , Humanos , Antibacterianos/farmacologia , Antibacterianos/administração & dosagem , Infecções Relacionadas à Prótese/microbiologia , Infecções Relacionadas à Prótese/tratamento farmacológico , Staphylococcus/efeitos dos fármacos , Vancomicina/farmacologia , Vancomicina/administração & dosagem , Propionibacterium acnes/efeitos dos fármacos , Gentamicinas/farmacologia , Gentamicinas/administração & dosagem , Artroplastia do Ombro , Ertapenem/farmacologia , Articulação do Ombro/microbiologia , Articulação do Ombro/cirurgia , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/tratamento farmacológico , Prótese de Ombro/microbiologia , Infecções por Bactérias Gram-Positivas/microbiologia , Infecções por Bactérias Gram-Positivas/tratamento farmacológico , beta-Lactamas/farmacologia , beta-Lactamas/administração & dosagem
8.
Fungal Biol ; 128(1): 1590-1595, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38341264

RESUMO

Psychedelic fungi have experienced a surge in interest in recent years. Most notably, the fungal secondary metabolite psilocybin has shown tremendous promise in the treatment of various psychiatric disorders. The mushroom species that produce this molecule are poorly understood. Here we sought to examine for the first time, the response of a psilocybin-producing species Psilocybe cubensis to casing (peat moss and vermiculite) and supplementation with gypsum (calcium sulfate dihydrate), two common practices in commercial mushroom cultivation. Mycelial samples of genetically authenticated P. cubensis were used to inoculate popcorn grain bags. The fully colonized bags of popcorn grain (0.15 kg) were transferred to bins of 0.85 kg pasteurized horse manure, with or without 1 cm thick layer of casing and/or 5 % gypsum. Our results indicate that the use of a casing layer significantly increases the biological efficiency (161.5 %), by approximately four fold, in comparison to control (40.5 %), albeit with a slight delay (∼2 days) for obtaining fruiting bodies and a somewhat reduced total tryptamine content (0.85 %) as gauged by High Performance Liquid Chromatography measurements. Supplementation with both casing and gypsum, however, appears to promote maximal yields (896.6 g/kg of dried substrate), with a biological efficiency of 89.6 %, while also maintaining high total tryptamine expressions (0.95 %). These findings, revealing methods for maximizing yield of harvest and expressions of psychoactive tryptamines, may prove useful for both home growers and commercial cultivators of this species, and ultimately support the growth of a robust industry with high quality natural products.


Assuntos
Agaricales , Psilocybe , Psilocibina , Humanos , Animais , Cavalos , Psilocibina/análise , Sulfato de Cálcio , Vocalização Animal , Triptaminas , Agaricales/química
9.
Environ Sci Pollut Res Int ; 31(7): 10417-10429, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38200192

RESUMO

There is a growing need to develop new strategies for rare earth element (REE) recovery from secondary resources. Herein, a novel approach to utilize biogenic silica (from rice husk) and metakaolin was employed to fabricate magnetic geopolymer (MGP) by incorporating metallic iron. The fabricated MGP adsorbent material was used to uptake Ce3+, La3+, and Nd3+ from synthetic solutions and real phosphogypsum leachate in batch and column modes. The MGP offers a negatively charged surface at pH above 2.7, and the uptake of REEs rises from pH 3 to 6. The kinetic study validated that the kinetics was much faster for Nd3+, followed by La3+ and Ce3+. A thermodynamic investigation validated the exothermic nature of the adsorption process for all selected REEs. The desorption experiment using 2 mol L-1 H2SO4 as the eluent demonstrated approximately 100% desorption of REEs from the adsorbent. After six adsorption-desorption cycles, the MGP maintained a high adsorption performance up to cycle five before suffering a significant decrease in performance in cycle six. The effectiveness of MGP was also assessed for its applicability in recovering numerous REEs (La3+, Ce3+, Pr3+, Sm3+, and Nd3+) from real leachate from phosphogypsum wastes, and the highest recovery was achieved for Nd3+ (95.03%) followed by Ce3+ (86.33%). The operation was also feasible in the column presenting suitable values of the length of the mass transfer zone. The findings of this investigation indicate that MGP adsorbent prepared via a simple route has the potential for the recovery of REEs from synthetic and real samples in both batch and continuous operations modes.


Assuntos
Sulfato de Cálcio , Metais Terras Raras , Oryza , Fósforo , Adsorção , Fenômenos Magnéticos
10.
J Environ Manage ; 353: 120020, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38278115

RESUMO

Dredged soil and phosphogypsum (PG) are waste materials that must be treated to reduce their negative environmental effects. Guided by the concept of waste treatment, this study proposed the use of PG as a supplementary cementitious material to stabilize waste-dredged soil, and calcium aluminate cement (CAC) was selected to further improve the strength of the cement-treated dredged soil. Several laboratory tests were conducted to investigate the pH, unconfined compressive strength (UCS), and failure strain of the cement-treated soils in different proportions. Microstructural and mineralogical tests were performed to reveal the mechanisms underlying the strength improvement of PG and CAC. The results showed that both PG and CAC enhanced the strength of cement-treated dredged soil. PG provided SO2- 4 to promote the formation of ettringite (aluminum ferrite trisulfate (AFt)), whereas CAC neutralized the acidity of PG and provided reactants to the reaction system, leading to an increase in the pH and strength with an increase in the relative CAC content. Meanwhile, an exponential relationship was obtained between pH and qu. Mineralogical changes demonstrated that the major hydration products of cementitious materials, such as calcium silicate (aluminate) hydrate (C-(A)-S-H), AFt, and calcium aluminate hydrate (C-A-H), enhanced the strength by filling pores between particles and bridging soil particles. However, excess CAC content may not be favorable for the later strength formation, the relative CAC content is recommended to be in the range of 40%-60%. Compared to using sand, the construction of a square kilometer of reclamation consumed 3.5 million tons of PG, and saved 1.54 billion USD by using dredged soil as raw material. Hence, the use of PG to treat dredged soils will have great environmental sustainability, economic benefits, and engineering value.


Assuntos
Compostos de Alumínio , Compostos de Cálcio , Fósforo , Solo , Resíduos Sólidos , Sulfato de Cálcio
11.
Environ Sci Pollut Res Int ; 31(7): 9920-9934, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36997776

RESUMO

Phosphogypsum (PG) is an industrial by-product of the transformation of phosphate rocks. For decades, PG has been a source of environmental concern due to the massive amount produced thus far, i.e., 7 billion tons, with a current production rate of 200-280 million tons per year. Phosphate minerals contain various impurities that precipitate and concentrate within PG. These impurities hinder PG usability in various sectors. This paper aims to purify PG using an innovative process based on staged valorization of PG. Initially, PG dissociation by ethylenediaminetetraacetic acid (EDTA) was optimized. After screening of different parameters and monitoring the ionic conductivity of solutions, it was disclosed that a pH-dependent solubilization process in the presence of EDTA resulted in high solubility of PG, up to 11.82 g/100 mL at pH > 11. Subsequently, a recovery of the purified PG by selective precipitation of calcium sulfate dihydrate (CSD) from obtained filtrate through pH adjustment to 3.5 were investigated. An abatement of 99.34% Cr, 97.15% Cd, 95.73% P2O5, 92.75% Cu, 92.38% Al2O3, 91.16% Ni, 74.58% Zn, 72.75% F, 61.43% MgO, 58.8% Fe2O3, 56.97% K2O, and 55.41% Ba was achieved. The process relied on the variation of EDTA chelation properties towards monovalent, divalent, and trivalent cations at different pHs. According to the findings of this study, a staged purification process in the presence of EDTA is an effective method for removing impurities from the industrial PG.


Assuntos
Sulfato de Cálcio , Fósforo , Sulfato de Cálcio/química , Ácido Edético , Fósforo/química , Fosfatos
12.
J Environ Manage ; 351: 119869, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38142596

RESUMO

The stacking of phosphogypsum has caused considerable phosphorus pollution in water bodies near phosphogypsum yards through surface runoff and underground infiltration. The phosphate oxygen isotope (δ18Op) tracing method has served as a valuable tool for tracing phosphorus pollution in water. However, the existing δ18Op enrichment and purification methods are complex, costly, and inefficient for phosphate recovery, particularly for phosphogypsum leachate with complex compositions. Herein, a simplified and optimized pretreatment method for δ18Op measurement in phosphogypsum leachate was developed. Zirconium/polyvinyl alcohol (Zr/PVA) gel beads showed good selectivity for phosphate enrichment from water at different initial phosphate concentrations with appropriate Zr/PVA dosage. The optimal enrichment pH value was <7, and the concentrated phosphate on the Zr/PVA gel beads could be effectively eluted in an alkaline environment. Compared with the traditional Fe or Mg coprecipitation enrichment methods, impurities in the solution showed no obvious adverse effects on the phosphate enrichment process. Further, the phosphate solution eluted from the Zr/PVA gel beads was purified by a simple adjustment of the pH instead of cation exchange in the traditional purification process. Magnesium ions in the solution could be completely removed when the pH ranged from 3.17 to 6.15, and the phosphate recovery rate could reach 98.66% when the eluent pH was 5.02. Fourier-transform infrared spectroscopy, X-ray diffraction, and energy-dispersive X-ray spectroscopy revealed that similar to traditional pretreatment method, the proposed method can obtain high-purity Ag3PO4 solids for δ18OP measurement and no isotope fractionation of δ18OP was observed. Therefore, this study provides a promising and reliable pretreatment method for δ18OP measurement, especially in complex phosphogypsum leachate.


Assuntos
Sulfato de Cálcio , Fosfatos , Fósforo , Isótopos de Oxigênio , Fósforo/química , Água
13.
J Environ Sci (China) ; 138: 428-438, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38135408

RESUMO

This study aimed to explore the chemical looping gasification (CLG) reaction characteristics of the metal-supported composite phosphogypsum (PG) oxygen carriers (OCs) and the thermodynamic mechanism. The FactSage 7.1 thermodynamic simulation was used to explore the oxygen release and H2S removal mechanisms. The experimental results showed that the syngas yield of CLG with PG-CuFe2O4 was more than that with PG-Fe2O320/CuO40 or PG-Fe2O330/CuO30 OC at 1023 K when the water vapor content was 0.3. Furthermore, the maximum syngas yield of the CO selectivity was 70.3% and of the CO2 selectivity was 23.8%. The H2/CO value was 0.78, and the highest carbon conversion efficiency was 91.9% in PG-CuFe2O4 at the gasification temperature of 1073 K. The metal-supported PG composite oxygen carrier was proved not only as an oxygen carrier to participate in the preparation of syngas but also as a catalyst to catalyze coal gasification reactions. Furthermore, both the experimental results and FactSage 7.1 thermodynamic analysis revealed that the trapping mechanism of H2S by composite OCs was as follows: CuO first lost lattice oxygen as an oxygen carrier to generate Cu2O, which, in turn, reacted with H2S to generate Cu2S. This study provided efficient guidance and reference for OC design in CLG.


Assuntos
Oxigênio , Fósforo , Oxigênio/química , Sulfato de Cálcio , Metais , Biomassa
14.
J Mol Graph Model ; 126: 108650, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37871455

RESUMO

While surfactants are widely used in phosphogypsum, their interactions with the phosphogypsum-water interface remain unclear. This study investigates the impact of three types of surfactants, namely polycarboxylate-based surfactant (PCE-TPEG), naphthalene-based surfactant (NS), and melamine-based surfactant (MS), on the performance of phosphorus building gypsum (PBG). Additionally, a nanoscale model of the PBG-surfactant-water interface is constructed using molecular dynamics to elucidate the mechanisms underlying the interaction between different surfactants and PBG at multiple scales. The results demonstrate that all surfactants enhance the mechanical properties of PBG. PCE-TPEG exhibits the most pronounced improvement. In the model, PCE-TPEG molecules likely undergo comb-like adsorption, while NS and MS molecules tend to adsorb on both ends of the crystal plane. Changes in the potential difference between CaSO4·2H2O and H2O, as well as between CaSO4·2H2O and the surfactant, play a crucial role in adsorption. PCE-TPEG, NS, and MS molecules tend to spread horizontally in a vacuum state. With the addition of water molecules, they transition to spatial adsorption. Ca2+ easily interacts with -COO- and -SO3- groups, leading to reduced migration and flexibility of the main chain. The adsorption process of surfactants at the gypsum-water interface occurs spontaneously and Electrostatic forces are the main driving factor. This study contributes to a more comprehensive understanding on the behaviour of the phosphorus building gypsum/surfactant composites.


Assuntos
Sulfato de Cálcio , Tensoativos , Tensoativos/química , Simulação de Dinâmica Molecular , Água/química , Fósforo
15.
Int J Mol Sci ; 24(24)2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38139007

RESUMO

Highly porous hydroxyapatite is sometimes considered toxic and useless as a biomaterial for bone tissue regeneration because of the high adsorption of calcium and phosphate ions from cell culture media. This negatively affects the osteoblast's growth in such ion-deprived media and suggests "false cytotoxicity" of tested hydroxyapatite. In our recent study, we showed that a small addition of calcium sulfate dihydrate (CSD) may compensate for this adsorption without a negative effect on other properties of hydroxyapatite-based biomaterials. This study was designed to verify whether such CSD-supplemented biomaterials may serve as antibiotic carriers. FTIR, roughness, mechanical strength analysis, drug release, hemocompatibility, cytotoxicity against human osteoblasts, and antibacterial activity were evaluated to characterize tested biomaterials. The results showed that the addition of 1.75% gypsum and gentamicin caused short-term calcium ion compensation in media incubated with the composite. The combination of both additives also increased antibacterial activity against bacteria representative of bone infections without affecting osteoblast proliferation, hemocompatibility, and mechanical parameters. Thus, gypsum and antibiotic supplementation may provide advanced functionality for bone-regeneration materials based on hydroxyapatite of a high surface area and increasingly high Ca2+ sorption capacity.


Assuntos
Antibacterianos , Durapatita , Humanos , Durapatita/metabolismo , Antibacterianos/farmacologia , Antibacterianos/metabolismo , Sulfato de Cálcio/farmacologia , Cálcio/metabolismo , Porosidade , Materiais Biocompatíveis/farmacologia , Materiais Biocompatíveis/metabolismo , Osteoblastos/metabolismo
16.
BMC Musculoskelet Disord ; 24(1): 822, 2023 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-37848868

RESUMO

BACKGROUND: At present, good results have been obtained in the treatment of hematogenous osteomyelitis(HO) in children by the use of drug-loaded calcium sulfate, but there are few clinical studies reported. The aim of this study was to investigate the clinical efficacy of radical debridement combined with drug-laden calcium sulphate antibiotics in paediatric haematogenous osteomyelitis. METHODS: In this study, we retrospectively analyzed the clinical data of 15 cases of pediatric hematogenous osteomyelitis admitted to our hospital in recent years. A total of 15 pediatric patients with HO treated in our hospital from January 2018 to February 2022 were included for evaluation. RESULTS: All 15 patients were treated with drug-laden calcium sulfate, and the antibiotic of choice was vancomycin in 14 cases and vancomycin combined with gentamicin in 1 case. The follow-up period ranged from 12 to 36 months, with a mean follow-up time of 24.73 months, and all children were treated with drug-laden calcium sulfate with satisfactory clinical outcomes. The results of serological examination showed that the preoperative white blood cell count level, C-reactive protein and erythrocyte sedimentation rate were higher than the postoperative ones, and the differences were statistically significant (P < 0.05).After the operation, referring to the treatment standard of McKee's osteomyelitis, 15 cases were cured without recurrence; According to the Lower Extremities Functional Scale, 12 cases were excellent, 2 cases were good and 1 case was moderate, with an excellent rate of 93.33%. Children with lower limb involvement could walk with full weight bearing, and gait was basically normal. CONCLUSION: Drug-loaded calcium sulfate is a good therapeutic method for the treatment of hematogenous osteomyelitis in children, with a effect of reducing complications and reducing recurrence.


Assuntos
Osteomielite , Vancomicina , Humanos , Criança , Sulfato de Cálcio , Estudos Retrospectivos , Antibacterianos/uso terapêutico , Osteomielite/diagnóstico , Desbridamento/métodos
17.
Zhongguo Gu Shang ; 36(9): 896-900, 2023 Sep 25.
Artigo em Chinês | MEDLINE | ID: mdl-37735085

RESUMO

OBJECTIVE: To investigate the clinical efficacy of acrylic cement (PMMA) mixed with calcium sulfate combined with percutaneous kyphoplasty (PKP) in the treatment of osteoporotic fracture (OVCF). METHODS: The clinical data of 191 patients with OVCF treated with PKP from January 2020 to March 2021 were retrospectively analyzed. Among them, 82 patients with 94 vertebral bodies were treated with PMMA mixed with calcium sulfate as the observation group, and 109 patients with 125 vertebral bodies were treated with pure PMMA as the control group. Among the 82 patients in the observation group, there were 16 males and 66 females, with a mean age of (75.35±11.22) years old, including 36 thoracic vertebrae and 58 lumbar vertebrae. In the control group, there were 109 patients, 22 males and 87 females, with an average age of (74.51±9.21) years old, including 63 thoracic vertebrae and 62 lumbar vertebrae. The visual analog scale (VAS) before operation and 1 day, 3 months and 1 year after operation were calculated. The Oswestry disability index (ODI), Cobb's angle, vertebral body height and the probability of postoperative bone cement leakage were used to analyze the efficacy of the two groups. RESULTS: All the patients were followed up for more than one year. Compared with the control group, there was no significant difference in operation time, bleeding volume and bone cement injection volume between the two groups(P>0.05), while the leakage rate of bone cement was significantly lower in the observation group (P<0.05). In addition, there was no significant difference in VAS, ODI, Cobb angle, and vertebral body height between the two groups before operation, and 1 day, 3 months, and 1 year after operation (P>0.05), but each index was improved compared with that before operation (P<0.05). CONCLUSION: PMMA mixed with calcium sulfate has equivalent efficacy in treating OVCF than PMMA alone, but can effectively reduce the probability of cement leakage.


Assuntos
Cifoplastia , Fraturas por Osteoporose , Feminino , Masculino , Humanos , Idoso , Idoso de 80 Anos ou mais , Pessoa de Meia-Idade , Polimetil Metacrilato , Sulfato de Cálcio/uso terapêutico , Fraturas por Osteoporose/cirurgia , Cimentos Ósseos/uso terapêutico , Estudos Retrospectivos , Vértebras Lombares/cirurgia
18.
J Pediatr Orthop ; 43(10): e816-e822, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37681304

RESUMO

BACKGROUNDS: The goals of this study were to (1) compare the effect of casting technique on biomechanical function with different casting materials and different cast core diameters, and (2) compare the strength of a cast based on the number of layers in relation to the core diameter. METHODS: Two standardized cylindrical cast model sizes were used to simulate forearm and short leg casts (core diameter: 60 mm, 100 mm) with 2 different casting techniques (non-smoothing vs. smoothing with lamination), utilizing 2 casting materials [fiberglass and Plaster of Paris (POP)]. Each cast was created using 3 different layers (Fiberglass: 2 to 4 layers; POP: 3 to 5 layers). Ultimate load-to-failure and flexural rigidity were analyzed through cyclic 4-point bend testing. RESULTS: The biomechanical comparison between forearm and short leg casts were significantly different regardless of the same number of layers for both casting materials and between 2 casting techniques. Increased cast thickness significantly increased the ultimate load-to-failure and bending strength. An increased core diameter size significantly decreased the cast's ultimate load-to-failure (fiberglass: 50% to 108%; POP: 10% to 93%) and bending strength (fiberglass: 17% to 35%; POP: 37% to 49%). Casting technique with smoothing with lamination technique had a negative biomechanical effect on POP and a minimal effect on fiberglass. CONCLUSION: The number of layers to apply for a cast should be based on the size of the extremity. Smoothing and lamination technique did not significantly improve the cast mechanical behavior. CLINICAL RELEVANCE: The findings of this study provide valuable evidence, analysis, and supplementary knowledge that helps guide physicians in proper casting technique.


Assuntos
Moldes Cirúrgicos , Deformidades Congênitas das Extremidades Inferiores , Humanos , Extremidade Superior , Antebraço , Sulfato de Cálcio
19.
J Environ Qual ; 52(5): 949-959, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37555696

RESUMO

Excess nutrients, such as phosphorus (P), in watersheds jeopardize water quality and trigger harmful algal blooms. Using phosphorus sorption material (PSM) to capture P from wastewater and agricultural runoff can help recover nutrients and prevent their water pollution. In this study, a novel designer biochar was generated by pyrolyzing woody biomass pretreated with a flue gas desulfurization gypsum. The removal of dissolved inorganic phosphorus (DIP) by the gypsum-incorporated designer biochar was more efficient than the gypsum, suggesting the pretreatment of biomass with the gypsum results in a synergic effect on enhancing DIP capture. The maximum P adsorption capacity of the designer biochar was more than 200 mg g-1 , which is one order of magnitude greater than that of the gypsum. This result clearly showed that the designer biochar is a better PSM to capture DIP from nutrient-contaminated water compared to the gypsum. Post-sorption characterization indicated that the sorption of DIP by the gypsum-incorporated biochar involves multiple mechanisms. The precipitation reactions of calcium (Ca) cations and P anions to form CaHPO4 and Ca3 (PO4 )2 precipitates on the highly alkaline surface of the designer biochar were identified as a main mechanism. By contrast, CaHPO4 ·2H2 O is the only precipitated product for DIP sorption by the gypsum. In addition, the initial solution pH and the coexisting bicarbonate had less effects on the DIP removal by the designer biochar in comparison with the gypsum, which further confirms that the former is an excellent PSM to capture DIP from a variety of aquatic media.


Assuntos
Sulfato de Cálcio , Carvão Vegetal , Sulfato de Cálcio/química , Carvão Vegetal/química , Fósforo/química , Agricultura , Adsorção
20.
Food Res Int ; 170: 113049, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37316030

RESUMO

Brewer's spent grain (BSG), a by-product of the brewing industry, has great potential as food additive. BSG is particularly rich in protein and fibre content which makes it an ideal nutritional fortifier for biscuits. However, adding BSG to biscuits can lead to changes in sensory perception and consumer acceptance. This study explored the temporal sensory profiles and drivers/inhibitors of liking in BSG-fortified biscuits. Six biscuit formulations were obtained from a design with factors oat flake particle size (three levels: 0.5 mm, small commercial flakes, large commercial flakes) and baking powder (two levels: with, without). Consumers (n = 104) tasted the samples, described their dynamic sensory perception using the Temporal Check-All-That-Apply (TCATA) method, and rated their liking on a 7-point categorical scale. The Clustering around Latent Variables (CLV) approach was used to group consumers into two clusters based on their preferences. The temporal sensory profiles and drivers/inhibitors of liking were investigated within each cluster. Foamy and Easy-to-swallow were sensory drivers of liking for both groups of consumers. However, inhibitors of liking were different in the two clusters: Dense and Hard-to-swallow for one cluster and Chewy, Hard-to-swallow and Hard for the other cluster. These findings give evidence that manipulating oat particle size and presence/absence of baking powder changes BSG-fortified biscuits' sensory profiles and consumer preferences. A complementary analysis of the area-under-curve of the TCATA data and inspection of individual temporal curves showed the dynamics of perception and showed how oat particle size and presence/absence of baking powder affected consumer perception and acceptance of BSG-fortified biscuits. The methods proposed in this paper can be further applied to understand how enriching products with ingredients that would otherwise go to waste affects acceptance in different consumer segments.


Assuntos
Sulfato de Cálcio , Suplementos Nutricionais , Compostos de Alúmen , Bicarbonato de Sódio , Grão Comestível
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA