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1.
Int J Nanomedicine ; 19: 4181-4197, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38766656

RESUMO

Purpose: The committed differentiation fate regulation has been a difficult problem in the fields of stem cell research, evidence showed that nanomaterials could promote the differentiation of stem cells into specific cell types. Layered double hydroxide (LDH) nanoparticles possess the regulation function of stem cell fate, while the underlying mechanism needs to be investigated. In this study, the process of embryonic stem cells (ESCs) differentiate to neural progenitor cells (NPCs) by magnesium aluminum LDH (MgAl-LDH) was investigated. Methods: MgAl-LDH with diameters of 30, 50, and 100 nm were synthesized and characterized, and their effects on the cytotoxicity and differentiation of NPCs were detected in vitro. Dot blot and MeRIP-qPCR were performed to detect the level of m6A RNA methylation in nanoparticles-treated cells. Results: Our work displayed that LDH nanoparticles of three different sizes were biocompatible with NPCs, and the addition of MgAl-LDH could significantly promote the process of ESCs differentiate to NPCs. 100 nm LDH has a stronger effect on promoting NPCs differentiation compared to 30 nm and 50 nm LDH. In addition, dot blot results indicated that the enhanced NPCs differentiation by MgAl-LDH was closely related to m6A RNA methylation process, and the major modification enzyme in LDH controlled NPCs differentiation may be the m6A RNA methyltransferase METTL3. The upregulated METTL3 by LDH increased the m6A level of Sox1 mRNA, enhancing its stability. Conclusion: This work reveals that MgAl-LDH nanoparticles can regulate the differentiation of ESCs into NPCs by increasing m6A RNA methylation modification of Sox1.


Assuntos
Diferenciação Celular , Nanopartículas , Células-Tronco Neurais , Diferenciação Celular/efeitos dos fármacos , Animais , Células-Tronco Neurais/efeitos dos fármacos , Células-Tronco Neurais/citologia , Células-Tronco Neurais/metabolismo , Camundongos , Nanopartículas/química , Metilação/efeitos dos fármacos , Hidróxidos/química , Hidróxidos/farmacologia , Metiltransferases/metabolismo , Metiltransferases/genética , Tamanho da Partícula , Células-Tronco Embrionárias/efeitos dos fármacos , Células-Tronco Embrionárias/citologia , Adenosina/farmacologia , Adenosina/química , Adenosina/análogos & derivados , Hidróxido de Alumínio/química , Hidróxido de Alumínio/farmacologia , Hidróxido de Magnésio/química , Hidróxido de Magnésio/farmacologia
2.
Sci Total Environ ; 932: 172878, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38697541

RESUMO

Excessive phosphorus (P) in eutrophic water induces cyanobacterial blooms that aggravate the burden of in-situ remediation measures. In order to ensure better ecological recovery, Flock & Lock technique has been developed to simultaneously sink cyanobacteria and immobilize P but requires a combination of flocculent and P inactivation agent. Here we synthesized a novel lanthanum-modified pyroaurite (LMP), as an alternative for Flock & Lock of cyanobacteria and phosphorus at the background of rich humic acid and suspended solids. LMP shows a P adsorption capacity of 36.0 mg/g and nearly 100 % removal of chlorophyll-a (Chl-a), turbidity, UV254 and P at a dosage (0.3 g/L) much lower than the commercial analogue (0.5 g/L). The resultant sediment (98.2 % as immobile P) exhibits sound stability without observable release of P or re-growth of cyanobacteria over a 50-day incubation period. The use of LMP also constrains the release of toxic microcystins to 1.4 µg/L from the sunk cyanobacterial cells, outperforming the commonly used polyaluminum chloride (PAC). Similar Flock & Lock efficiency could also be achieved in real eutrophic water. The outstanding Flock & Lock performance of LMP is attributable to the designed La modification. During LMP treatment, La acts as not only a P binder by formation of LaPO4, but also a coagulant to create a synergistic effect with pyroaurite. The controlled hydrolysis of surface La(III) over pyroaurite aided the possible formation of La(III)-pyroaurite networking structure, which significantly enhanced the Flock & Lock process through adsorption, charge neutralization, sweep flocculation and entrapment. In the end, the preliminary economic analysis is performed. The results demonstrate that LMP is a versatile and cost-effective agent for in-situ remediation of eutrophic waters.


Assuntos
Eutrofização , Lantânio , Microcystis , Fósforo , Lantânio/química , Poluentes Químicos da Água/análise , Hidróxido de Alumínio/química , Adsorção , Recuperação e Remediação Ambiental/métodos
3.
Sci Total Environ ; 939: 173378, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-38795993

RESUMO

Cyanobacterial blooms have been a growing problem in water bodies and attracted attention from researcher and water companies worldwide. Different treatment methods have been researched and applied either inside water treatment plants or directly into reservoirs. We tested a combination of coagulants, polyaluminium chloride (PAC) and iron(III) chloride (FeCl3), and ballasts, luvisol (LUV) and planosol (PLAN), known as the 'Floc and Sink' technique, to remove positively buoyant cyanobacteria from a tropical reservoir water. Response Surface Methodology (RSM) based on Central Composite Design (CCD) was used to optimize the two reaction variables - coagulant dosage (x1) and ballast dosage (x2) to remove the response variables: chlorophyll-a, turbidity, true color, and organic matter. Results showed that the combination of LUV with PAC effectively reduced the concentration of the response variables, while PLAN was ineffective in removing cyanobacteria when combined to PAC or FeCl3. Furthermore, FeCl3 presented poorer floc formation and lower removal efficiency compared to PAC. This study may contribute to the theoretical and practical knowledge of the algal biomass removal for mitigating eutrophication trough different dosages of coagulants and ballasts.


Assuntos
Cianobactérias , Eutrofização , Cianobactérias/crescimento & desenvolvimento , Purificação da Água/métodos , Cloretos/análise , Floculação , Compostos Férricos , Hidróxido de Alumínio/química , Solo/química
4.
Biomaterials ; 308: 122569, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38626556

RESUMO

In subunit vaccines, aluminum salts (Alum) are commonly used as adjuvants, but with limited cellular immune responses. To overcome this limitation, CpG oligodeoxynucleotides (ODNs) have been used in combination with Alum. However, current combined usage of Alum and CpG is limited to linear mixtures, and the underlying interaction mechanism between CpG and Alum is not well understood. Thus, we propose to chemically conjugate Alum nanoparticles and CpG (with 5' or 3' end exposed) to design combination adjuvants. Our study demonstrates that compared to the 3'-end exposure, the 5'-end exposure of CpG in combination adjuvants (Al-CpG-5') enhances the activation of bone-marrow derived dendritic cells (BMDCs) and promotes Th1 and Th2 cytokine secretion. We used the SARS-CoV-2 receptor binding domain (RBD) and hepatitis B surface antigen (HBsAg) as model antigens to demonstrate that Al-CpG-5' enhanced antigen-specific antibody production and upregulated cytotoxic T lymphocyte markers. Additionally, Al-CpG-5' allows for coordinated adaptive immune responses even at lower doses of both CpG ODNs and HBsAg antigens, and enhances lymph node transport of antigens and activation of dendritic cells, promoting Tfh cell differentiation and B cell activation. Our novel Alum-CPG strategy points the way towards broadening the use of nanoadjuvants for both prophylactic and therapeutic vaccines.


Assuntos
Adjuvantes Imunológicos , Hidróxido de Alumínio , Óxido de Alumínio , Células Dendríticas , Antígenos de Superfície da Hepatite B , Nanopartículas , Oligodesoxirribonucleotídeos , Adjuvantes Imunológicos/farmacologia , Animais , Nanopartículas/química , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Oligodesoxirribonucleotídeos/química , Oligodesoxirribonucleotídeos/farmacologia , Antígenos de Superfície da Hepatite B/imunologia , Antígenos de Superfície da Hepatite B/metabolismo , Hidróxido de Alumínio/química , Hidróxido de Alumínio/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Feminino , Citocinas/metabolismo , Compostos de Alúmen/química , Compostos de Alúmen/farmacologia
5.
J Hazard Mater ; 471: 134314, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38640668

RESUMO

Inorganic coagulants could effectively precipitate algae cells but might increase the potential risks of cell damage and coagulant residue. This study was conducted to critically investigate the suitability of polyaluminum (PAC), FeCl3 and TiCl4 for algae-laden water treatment in terms of the trade-off between algal substance removal, cell viability, and coagulant residue. The results showed that an appropriate increase in coagulant dosage contributed to better coagulation performance but severe cell damage and a higher risk of intracellular organic matter (IOM) release. TiCl4 was the most destructive, resulting in 60.85% of the algal cells presenting membrane damage after coagulation. Intense hydrolysis reaction of Ti salts was favorable for the formation of larger and more elongated, dendritic structured flocs than Al and Fe coagulants. TiCl4 exhibited the lowest residue level and remained in the effluents mainly in colloidal form. The study also identified charge neutralization, chemisorption, enmeshment, and complexation as the dominant mechanisms for algae water coagulation by metal coagulants. Overall, this study provides the trade-off analyses between maximizing algae substance removal and minimizing potential damage to cell integrity and is practically valuable to develop the most suitable and feasible technique for algae-laden water treatment.


Assuntos
Hidróxido de Alumínio , Sobrevivência Celular , Compostos Férricos , Floculação , Titânio , Purificação da Água , Purificação da Água/métodos , Hidróxido de Alumínio/química , Sobrevivência Celular/efeitos dos fármacos , Floculação/efeitos dos fármacos , Compostos Férricos/química , Titânio/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/toxicidade , Cloretos/química
6.
Int J Biol Macromol ; 266(Pt 1): 131113, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38531524

RESUMO

In order to prevent uranium pollution and recovery uranium resources, it was necessary to find a highly efficient adsorbent for radioactive wastewater treatment. Herein, U(VI) imprinted polyethyleneimine (PEI) incorporated chitosan/layered hydrotalcite composite foam (IPCL) was synthesized by combining ion-imprinting and freeze-drying techniques. IPCL has a high amino/imino content and an ultralight macroporous structure, making it capable of efficiently adsorbing U(VI) and easy to separate; Especially after ion-imprinting, vacancies matching the size of uranyl ions were formed, significantly improving U(VI) selectivity. The adsorption isotherms and adsorption kinetics were in accordance with the Freundlich model and PSO model respectively, indicating that heterogeneous adsorption of U(VI) by the adsorbents. The adsorption capacity of IPCL-2 for U(VI) reached 278.8. mg/g (under the conditions of optimal pH 5.0, temperature of 298 K, contact time of 2 h, and adsorbent dosage of 0.2 g/L), which is almost double of that for the non-imprinted foam (PCL-2, 138.2 mg/g), indicating that IPCL-2 can intelligently recognize U(VI). The heterogeneous adsorption mechanism of U(VI) by IPCL-2 involves complexation, ion-exchange and isomorphic substitution. The adsorption of U(VI) by IPCL-2 is spontaneous and endothermic. IPCL-2 has excellent adsorption performance for U(VI), and is a promising adsorbent for radioactive pollution control.


Assuntos
Hidróxido de Alumínio , Quitosana , Hidróxido de Magnésio , Polietilenoimina , Urânio , Urânio/química , Polietilenoimina/química , Quitosana/química , Adsorção , Hidróxido de Alumínio/química , Cinética , Hidróxido de Magnésio/química , Porosidade , Concentração de Íons de Hidrogênio , Purificação da Água/métodos , Temperatura , Íons/química
7.
Environ Res ; 252(Pt 1): 118777, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38527723

RESUMO

Anaerobic digestion of phenolic wastewater by anaerobic membrane bioreactor (AnMBR) has revealed increasing attractiveness, but the application of AnMBRs for treating high-strength phenolic wastewater faces challenges related to elevated phenol stress and membrane fouling. In this study, the coupling of AnMBR and polyaluminum chloride (PAC) was developed for efficient treatment of high-strength phenolic wastewater. The system achieved robust removal efficiencies of phenol (99%) and quinoline (98%) at a gradual increase of phenol concentration from 1000 to 5000 mg/L and a constant quinoline concentration of 100 mg/L. The dosing of PAC could effectively control the membrane fouling rate with the transmembrane pressure (TMP) increasing rate as low as 0.17 kPa/d. The robust performances were mainly attributed to the favorable retention of functional microbes through membrane interception, while pulse cross flow buffered against phenol stress and facilitated cake layer removal. Meanwhile, the enriched core functional microbes, such as Syntrophorhabdus, Syntrophus, Mesotoga and Methanolinea, played a crucial role in further reduction of phenol stress. Notably, the significant presence of biomacromolecule degrader, such as Levilinea, contributed to membrane fouling mitigation through extracellular polymer degradation. Moreover, the enlargement of particle size distribution (PSD) by PAC was expected to mitigate membrane fouling. This study provided a promising avenue for sustainable treatment of high-strength phenolic wastewater.


Assuntos
Reatores Biológicos , Membranas Artificiais , Eliminação de Resíduos Líquidos , Águas Residuárias , Águas Residuárias/química , Eliminação de Resíduos Líquidos/métodos , Anaerobiose , Hidróxido de Alumínio/química , Fenóis/análise , Poluentes Químicos da Água/análise
8.
J Pharm Sci ; 113(6): 1478-1487, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38246363

RESUMO

Vaccine manufacturing is one of the most challenging and complex processes in pharmaceutical industry, and the process control strategy is critical for the safety, effectiveness, and consistency of a vaccine. The efficacy of aluminum salt adjuvant on vaccines strongly depends on its physicochemical properties, such as size, structure, surface charge, etc. However, stresses during the vaccine manufacturing may affect the stability of adjuvant. In this study, the impacts of cold/thermal stress, autoclaving, pumping, mixing, and filling shear stress on the physicochemical properties of aluminum hydroxide (AH) adjuvant were evaluated as part of the manufacturing process development. The results showed that the autoclaving process would slightly influence the structure and properties of the investigated AH adjuvant, but thermal incubation at 2-8 °C, 25 °C and 40 °C for 4 weeks did not. However, -20 °C freezing AH adjuvant led to the adjuvant agglomeration and rapid sedimentation. For the high shear stress study with mixing at 500 rpm in a 1-L mixing bag and pumping at 220 rpm for up to 24 h, the average particle dimension of the bulk AH adjuvant decreased, along with decreasing protein adsorption ratio. The studies indicate that various stresses during manufacturing process could affect the structure and physicochemical properties of AH adjuvant, which calls for more attention on the control of adjuvant process parameters during manufacturing.


Assuntos
Adjuvantes Imunológicos , Hidróxido de Alumínio , Vacinas , Hidróxido de Alumínio/química , Vacinas/química , Adjuvantes Imunológicos/química , Tamanho da Partícula , Estabilidade de Medicamentos
9.
Environ Sci Technol ; 58(4): 2017-2026, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38214482

RESUMO

Understanding the dissolution of boehmite in highly alkaline solutions is important to processing complex nuclear waste stored at the Hanford (WA) and Savannah River (SC) sites in the United States. Here, we report the adsorption of model carboxylates on boehmite nanoplates in alkaline solutions and their effects on boehmite dissolution in 3 M NaOH at 80 °C. Although expectedly lower than at circumneutral pH, adsorption of oxalate occurred at pH 13, with adsorption decreasing linearly to 3 M NaOH. Classical molecular dynamics simulations suggest that the adsorption of oxalate dianions onto the boehmite surface under high pH can occur through either inner- or outer-sphere complexation mechanisms depending on adsorption sites. However, both adsorption models indicate relatively weak binding, with an energy preference of 1.26 to 2.10 kcal/mol. By preloading boehmite nanoplates with oxalate or acetate, we observed suppression of dissolution rates by 23 or 10%, respectively, compared to pure solids. Scanning electron microscopy and transmission electron microscopy characterizations revealed no detectable difference in the morphologic evolution of the dissolving boehmite materials. We conclude that preadsorbed carboxylates can persist on boehmite surfaces, decreasing the density of dissolution-active sites and thereby adding extrinsic controls on dissolution rates.


Assuntos
Hidróxido de Alumínio , Óxido de Alumínio , Hidróxido de Sódio , Hidróxido de Alumínio/química , Óxido de Alumínio/química , Adsorção , Oxalatos
10.
J Pharm Sci ; 113(2): 455-462, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-37813301

RESUMO

Aluminum hydroxide adjuvants are widely used in human vaccines, such as diphtheria, tetanus, hepatitis A and hepatitis B vaccines. The adsorption of antigens on aluminum hydroxide adjuvants determines the immune boosting effect of vaccines, but it is not clear how changes in physicochemical properties resulting from the production and formulation processes affect the adsorption of aluminum hydroxide adjuvants with antigens. In this study, the commercial aluminum hydroxide adjuvant Alhydrogel® was pretreated by commonly used processes such as autoclaving and calcination, and the changes of aluminum hydroxide adjuvant in physicochemical properties during the treatment were then comprehensively characterized. The adsorption of ovalbumin (OVA) with treated Alhydrogel®, was also investigated, it was found that the decrease in specific surface area caused by the autoclaving process reduced the adsorptive capacity of the antigen, and the adsorptive strength of antigen was decreased only when the surface hydroxyl groups and chemically bound water of adjuvant were reduced by calcination. These findings help to optimize the production and formulation process of adjuvants for the rational regulation of antigen adsorption in vaccines.


Assuntos
Hidróxido de Alumínio , Alumínio , Humanos , Hidróxido de Alumínio/química , Adsorção , Adjuvantes Imunológicos/química , Adjuvantes Farmacêuticos/química , Vacinas contra Hepatite B
11.
Water Res ; 249: 120888, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38039821

RESUMO

Soil washing is currently attracting attention as a promising remediation strategy for land contaminated with per- and polyfluoroalkyl substances (PFAS). In the soil washing process, the contaminant is transferred from the soil into the liquid phase, producing a PFAS contaminated process water. One way to treat such process water is to use coagulation and flocculation; however, few studies are available on the performance of coagulation and flocculation for removing PFAS from such process water. This study evaluated 6 coagulants and flocculants (polyaluminium chloride (PACl), zirconium oxychloride octahydrate, cationic and anionic polyacrylamide, Polyclay 685 and Perfluor Ad®), for the treatment of a proxy PFAS contaminated washing water, spiked with PFAS concentrations found at typical Aqueous Film Forming Foam (AFFF) contaminated sites. PFAS removal efficiencies (at constant pH) varied greatly depending on the coagulants and flocculants, as well as the dosage used and the targeted PFAS. All tested coagulants and flocculants reduced the turbidity by >95%, depending on the dosage. Perfluor Ad®, a specially designed coagulant, showed the highest removal efficiency for all longer chain (>99%) and shorter chain PFAS (>68%). The cationic polyacrylamide polymer removed longer chain PFAS up to an average of 80%, whereas average shorter chain PFAS removal was lower (<30%). The two metal-based coagulants tested, PACl and zirconium, removed longer chain PFAS by up to an average of 61% and shorter chain PFAS up to 48%. Polyclay 685, a mixture of powdered activated carbon (PAC) and aluminium sulphate, removed longer chain PFAS by 90% and shorter chain PFAS on average by 76%, when very high dosages of the coagulant were used (2,000 mg/L). PFAS removal efficiencies correlated with chain length and headgroup. Shorter chain PFAS removal was dependent on electrostatic interaction with the precipitating flocs, whereas for longer chain PFAS, hydrophobic interactions between apolar functional groups and flocs created by the coagulant/flocculant, dissolved organic matter and suspended solids played a major role. The results of this study showed that by selecting the most efficient coagulant and aqueous conditions, a greater amount of PFAS can be removed from process waters in soil washing facilities, and thus included as part of various treatment trains.


Assuntos
Fluorocarbonos , Poluentes Químicos da Água , Purificação da Água , Solo , Floculação , Hidróxido de Alumínio/química , Purificação da Água/métodos , Poluentes Químicos da Água/química
12.
Int J Pharm ; 648: 123581, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37931728

RESUMO

Most licensed human vaccines are based on liquid dosage forms but have poor storage stability and require continuous and expensive cold-chain storage. In contrast, the use of solid vaccine dosage forms produced by for example spray drying, extends shelf life and eliminates the need for a cold chain. Zinc oxide (ZnO)-based nanoparticles display immunomodulatory properties, but their adjuvant effect as a dry powder formulation is unknown. Here, we show that reconstituted dry powder formulations of ZnO particles containing the model antigen ovalbumin (OVA) induce antigen-specific CD8+ T-cell and humoral responses. By systematically varying the ratio between ZnO and mannitol during spray drying, we manufactured dry powder formulations of OVA-containing ZnO particles that displayed: (i) a spherical or wrinkled surface morphology, (ii) an aerodynamic diameter and particle size distribution optimal for deep lung deposition, and (iii) aerosolization properties suitable for lung delivery. Reconstituted dry powder formulations of ZnO particles were well-tolerated by Calu-3 lung epithelial cells. Furthermore, almost equivalent OVA-specific serum antibody responses were stimulated by reconstituted ZnO particles, OVA adjuvanted with Alhydrogel®, and OVA adjuvanted with the cationic adjuvant formulation 01 (CAF®01). However, reconstituted dry powder ZnO particles and OVA adjuvanted with Alhydrogel® induced significantly lower OVA-specific CD8+CD44+ T-cell responses in the spleen than OVA adjuvanted with CAF®01. Similarly, reconstituted dry powder ZnO particles activated significantly lower percentages of follicular helper T cells and germinal center B cells in the draining lymph nodes than OVA adjuvanted with CAF®01. Overall, our results show that reconstituted dry powder formulations of ZnO nanoparticles can induce antigen-specific antibodies and can be used in vaccines to enhance antigen-specific humoral immune responses against subunit protein antigens.


Assuntos
Vacinas , Óxido de Zinco , Humanos , Hidróxido de Alumínio/química , Ovalbumina , Pós , Adjuvantes Imunológicos , Adjuvantes Farmacêuticos , Antígenos , Anticorpos
13.
Int J Mol Sci ; 24(6)2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36982226

RESUMO

This work represents research into materials designed to improve the environment. The study was carried out on aluminum hydroxide xerogels and alumina catalysts obtained by the Controlled Double Jet Precipitation (CDJP) process at different pH values. It has been shown that the pH of the CDJP process determines the content of aluminum-bound nitrate ions in the aluminum hydroxide. These ions are removed at a higher temperature than the decomposition of ammonium nitrate. The high content of aluminum-bound nitrate ions determines the structural disorder of the alumina and the high content of the penta-coordinated alumina catalyst.


Assuntos
Óxido de Alumínio , Nitratos , Óxido de Alumínio/química , Hidróxido de Alumínio/química , Alumínio/química , Espectroscopia de Infravermelho com Transformada de Fourier
14.
Water Res ; 235: 119909, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36996750

RESUMO

Application of poly-aluminum chloride (PACl) coagulant is a popular mode of water treatment worldwide because of the high capacity of PACl to neutralize charge. The manufacture and use of PACls with various basicities in different regions around the world suggest that the characteristics of the raw water are important determinants of the efficacy of PACl application. However, attention has not been fully paid to the effects of water quality other than the substances to be removed. In this study, two typical PACls with different basicities were used to investigate why the performance of PACls depends on the characteristics of the raw water. We focused on the concentrations of inorganic ions in the raw water. Use of high-basicity PACl (HB-PACl) with a high content of polymeric-colloidal species (Alb+Alc) resulted in very slow floc formation and little turbidity removal in raw water with low concentrations of sulfate ions. The performance of the HB-PACl was inferior to that of normal-basicity PACl (NB-PACl), although the charge-neutralization capacity of the HB-PACl was higher. Rates of floc formation were strongly correlated with the rate of aluminum precipitation by hydrolysis reaction, which was identified as an indicator for evaluating the compatibility of raw water with PACl treatment. Among the common ions in natural water, the sulfate ion had the greatest ability to hydrolyze and precipitate PACl because of its divalency and tetrahedral structure. This conclusion followed from experimental results showing similar effects for selenate and chromate ions as for sulfate ions and somewhat smaller effects for thiosulfate ions. Bicarbonate ions and natural organic matter affected PACl hydrolysis-precipitation, but chloride ions, nitrate ions, and cations had little effect on PACl hydrolysis-precipitation. Interestingly, the abilities of sulfate ions to hydrolyze HB-PACl and NB-PACl were very similar, but bicarbonate ions were less effective in hydrolyzing HB-PACl than NB-PACl, and bicarbonate ions contributed little to the hydrolysis-precipitation of HB-PACl in raw water with normal alkalinity. Therefore, sufficient coagulation with HB-PACl therefore usually requires a certain concentration of sulfate ions in water to be treated. The implication is that which anions are most influential to the hydrolysis-precipitation of PACl, and thus to PACl's coagulation ability depends on the constituents of the PACl.


Assuntos
Cloretos , Purificação da Água , Bicarbonatos , Hidróxido de Alumínio/química , Alumínio/química , Sulfatos/química , Purificação da Água/métodos , Floculação
15.
Molecules ; 28(2)2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36677641

RESUMO

The long-term biodistribution of non-biodegradable microstructures or nanostructures used in vaccinations is widely unknown. This is the case for aluminum oxyhydroxide, the most widely used vaccine adjuvant, which is a nanocrystalline compound that spontaneously forms nanoprecipitates. Although generally well-tolerated, aluminum oxyhydroxide is detected in macrophages a long time after vaccination in individuals predisposed to the development of systemic and neurological aspects of the autoimmune (inflammatory) syndrome induced by modified adjuvant. In the present study, we established that the terminal sterilization of aluminum oxyhydroxide by autoclaving in final container vials produced measurable changes in its physicochemical properties. Moreover, we found that these changes included (1) a decreasing in the pH of aluminum oxyhydroxide solutions, (2) a reduction in the adsorption capacity of bovine serum albumin, (3) a shift in the angle of X-ray diffraction, (4) a reduction in the lattice spacing, causing the crystallization and biopersistence of modified aluminum oxyhydroxide in the macrophage, as well as in muscle and the brain.


Assuntos
Alumínio , Vacinas , Humanos , Distribuição Tecidual , Adjuvantes Imunológicos/farmacologia , Adjuvantes Imunológicos/química , Adjuvantes Farmacêuticos , Vacinas/química , Hidróxido de Alumínio/química
16.
Chemosphere ; 309(Pt 2): 136802, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36220437

RESUMO

Improving the adsorption ability of layered double hydroxide (LDH) has been considered as a promising strategy to promote its photodegradation of aqueous pollutants. In this work, nickel-aluminium layered double hydroxides (NiAl-LDH)/biochar nanocomposites were prepared using a simple coprecipitation method, and then applied in synergistic adsorption-photodegradation of tetracycline (TC) in aqueous solutions. In addition, the governing TC removal mechanisms by the nanocomposites were revealed. All NiAl-LDH/BC samples showed strong adsorption and photodegradation of TC. The Langmuir maximum TC adsorption capacity of optimized NiAl-LDH/BC-0.5 reached 124.2 mg/g, which was much better than that of NiAl-LDH (56.1 mg/g) and biochar (11.1 mg/g). Besides, TC photodegradation rate constant of NiAl/BC-0.5 was 3.6 and 4.4 times of that of NiAl-LDH and BC, respectively. The NiAl/BC-0.5 exhibited the maximum TC adsorption-photodegradation efficiency 94.4% in 90 min compared to NiAl-LDH (73.7%) and BC (48.2%). The rate constant of modified Elovich kinetic model for synergistic adsorption and photodegradation on NiAl/BC-0.5 (9.477 min-1) was the highest among the composites. The NiAl-LDH/BC had significantly larger BET surface areas than NiAl-LDH and BC. The step scheme (S-scheme) heterostructures were constructed on the interface of BC and NiAl-LDH in nanocomposites, which facilitated the transfer of photo-induced charges. This work demonstrates that combination of NiAl-LDH and biochar can create synergy for TC adsorption-photodegradation, which is a promising and green strategy.


Assuntos
Alumínio , Poluentes Químicos da Água , Adsorção , Alumínio/química , Níquel/química , Poluentes Químicos da Água/química , Fotólise , Hidróxidos/química , Tetraciclina , Hidróxido de Alumínio/química , Antibacterianos
17.
Proc Natl Acad Sci U S A ; 119(36): e2205983119, 2022 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-36037341

RESUMO

Effective antitumor immunity in mice requires activation of the type I interferon (IFN) response pathway. IFNα and IFNß therapies have proven promising in humans, but suffer from limited efficacy and high toxicity. Intratumoral IFN retention ameliorates systemic toxicity, but given the complexity of IFN signaling, it was unclear whether long-term intratumoral retention of type I IFNs would promote or inhibit antitumor responses. To this end, we compared the efficacy of IFNα and IFNß that exhibit either brief or sustained retention after intratumoral injection in syngeneic mouse tumor models. Significant enhancement in tumor retention, mediated by anchoring these IFNs to coinjected aluminum-hydroxide (alum) particles, greatly improved both their tolerability and efficacy. The improved efficacy of alum-anchored IFNs could be attributed to sustained pleiotropic effects on tumor cells, immune cells, and nonhematopoietic cells. Alum-anchored IFNs achieved high cure rates of B16F10 tumors upon combination with either anti-PD-1 antibody or interleukin-2. Interestingly however, these alternative combination immunotherapies yielded disparate T cell phenotypes and differential resistance to tumor rechallenge, highlighting important distinctions in adaptive memory formation for combinations of type I IFNs with other immunotherapies.


Assuntos
Hidróxido de Alumínio , Imunoterapia , Interferon Tipo I , Compostos de Alúmen/química , Hidróxido de Alumínio/química , Animais , Antineoplásicos/uso terapêutico , Modelos Animais de Doenças , Humanos , Imunoterapia/métodos , Imunoterapia/normas , Interferon Tipo I/química , Interferon Tipo I/uso terapêutico , Interferon-alfa , Interferon beta , Nanopartículas Metálicas/química , Nanopartículas Metálicas/uso terapêutico , Camundongos
18.
Chemosphere ; 306: 135464, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35760140

RESUMO

Hydrotalcite-like anionic clays (HTs) also known as Layered double hydroxides (LDHs) have been developed as multifunctional materials in numerous applications related to catalysis, adsorption, and ion-exchange processes. These materials constitute an important class of ionic lamellar solid clays of Brucite-like structure which comprise of consecutive layers of divalent and trivalent metal cations with charge balancing anions and water molecules in interlayer space. These materials have received increasing attention in research due to their interesting properties namely layered structure, ease of preparation, flexible tunability, ability to intercalate different types of anions, electronic properties, high thermal stability, high biocompatibility, and easy biodegradation. Moreover, HTs/LDHs have unique tailorable and tuneable characteristics such as both acidic and basic sites, anion exchange capability, surface area, basal spacing, memory effect, and also exhibit high exchange capacities, which makes them versatile materials for a wide range of applications and extended their horizons to diverse areas of science and technology. This study enlightens the various rational researches related to the synthetic methods and features focusing on synthesis and/or fabrication with other hybrids and their applications. The diverse applications (namely catalyst, adsorbent to toxic chemicals, agrochemicals management, non-toxic flame retardants, and recycling of plastics) of these multifunctional materials related to a clean and sustainable environment were also summarized.


Assuntos
Hidróxido de Alumínio , Hidróxido de Magnésio , Hidróxido de Alumínio/química , Argila , Hidróxidos/química , Hidróxido de Magnésio/química
19.
Water Res ; 220: 118633, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35613484

RESUMO

The hydrolysate species of metal-based coagulants and the binding sites of humic acid (HA) are highly dependent on the pH conditions. Exploring the binding sites and modes between coagulant hydrolysates and HA molecules is critical to understanding the coagulation mechanism. In this paper, the binding behavior between HA molecules and the hydrolysates of a polyaluminum-titanium chloride composite coagulant (PATC) was investigated under different pH conditions by semi-quantitative FTIR and XPS. It was found that oligomeric and mesopolymeric hydrolysates were the dominant species under acid conditions, which could complex with the hydroxyl and carboxyl groups of HA by forming COAl/Ti coordinate bonds. However, large amounts of H+ could compete with Al3+ and weaken the removal efficiency of HA. With the increase of pH, the hydrolysis process of the PATC and the deprotonation of HA were simultaneously underway. Under weakly acid conditions, the complexation of the aluminum hydrolysates with carboxyl groups was improved due to the gradually diminishing competition of H+ and the enhanced charge neutralization of the further polymerized hydrolysates. Consequently, the maximum UV254 removal by adding PATC was observed at pH 6. Under alkaline conditions, the sweeping effect of amorphous hydroxide dominated the HA removals, which was accompanied by the surface complexation of Al/Ti nuclear with carboxyl groups as well as the hydrogen bonds between hydroxyl and hydroxide. This study provides a new clue for the interaction mechanisms between the hydrolysates of composite coagulants and the dominant functional groups of HA at various pH conditions.


Assuntos
Substâncias Húmicas , Purificação da Água , Alumínio/química , Hidróxido de Alumínio/química , Cloretos , Floculação , Substâncias Húmicas/análise , Radical Hidroxila , Titânio/química
20.
Cell ; 185(4): 614-629.e21, 2022 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-35148840

RESUMO

Activation of the innate immune system via pattern recognition receptors (PRRs) is key to generate lasting adaptive immunity. PRRs detect unique chemical patterns associated with invading microorganisms, but whether and how the physical properties of PRR ligands influence the development of the immune response remains unknown. Through the study of fungal mannans, we show that the physical form of PRR ligands dictates the immune response. Soluble mannans are immunosilent in the periphery but elicit a potent pro-inflammatory response in the draining lymph node (dLN). By modulating the physical form of mannans, we developed a formulation that targets both the periphery and the dLN. When combined with viral glycoprotein antigens, this mannan formulation broadens epitope recognition, elicits potent antigen-specific neutralizing antibodies, and confers protection against viral infections of the lung. Thus, the physical properties of microbial ligands determine the outcome of the immune response and can be harnessed for vaccine development.


Assuntos
Adjuvantes Imunológicos/farmacologia , Antígenos Virais/imunologia , Candida albicans/química , Mananas/imunologia , Hidróxido de Alumínio/química , Animais , Anticorpos Neutralizantes/imunologia , Especificidade de Anticorpos/imunologia , Linfócitos B/imunologia , COVID-19/imunologia , COVID-19/prevenção & controle , COVID-19/virologia , Chlorocebus aethiops , Epitopos/imunologia , Imunidade Inata , Imunização , Inflamação/patologia , Interferons/metabolismo , Lectinas Tipo C/metabolismo , Ligantes , Pulmão/imunologia , Pulmão/patologia , Pulmão/virologia , Linfonodos/imunologia , Linfonodos/metabolismo , Macrófagos/metabolismo , Camundongos Endogâmicos C57BL , Seios Paranasais/metabolismo , Subunidades Proteicas/metabolismo , Lectina 1 Semelhante a Ig de Ligação ao Ácido Siálico/metabolismo , Solubilidade , Glicoproteína da Espícula de Coronavírus/metabolismo , Linfócitos T/imunologia , Fator de Transcrição RelB/metabolismo , Células Vero , beta-Glucanas/metabolismo
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