RESUMEN

We address the targeted destruction of Karenia brevis using the algaecide calcium peroxide, in tandem with the flocculation and sinking of the species. The specific aspect of the approach is the incorporation of the algaecide within the floc to rapidly kill K. brevis, thus minimizing escape of cells from the floc and reentry to the water column. CaO2 gradually produces H2O2, which diffuses through cell membranes and induces oxidative stress, leading to cell death via excessive reactive oxygen species (ROS) formation. The effect of varying doses of calcium peroxide on K. brevis cells was measured with pulse amplitude modulated fluorometry and indicated that doses as low as 30 mg/L when integrated into flocs are effective in suppressing photosynthesis. Cell viability assays also indicate that such low levels are sufficient to cause cell death in a 3-6 hour time period. Thus, the proposed technology involving the incorporation of calcium peroxide in a cationic flocculating agent (polyaluminum chloride, PAC) leads to an inexpensive and scalable technology to mitigate harmful algal blooms of K. brevis.

Asunto(s)

Dinoflagelados , Peróxidos , Dinoflagelados/fisiología , Dinoflagelados/efectos de los fármacos , Floculación , Floraciones de Algas Nocivas , Hidróxido de Aluminio/farmacología , Hidróxido de Aluminio/química , Óxidos/farmacología , Peróxido de Hidrógeno , Especies Reactivas de Oxígeno/metabolismo , Fotosíntesis/efectos de los fármacos

RESUMEN

BACKGROUND: Rabbit hemorrhagic disease (RHD) is an acute infectious disease that damages the rabbit industry by producing significant mortality rates in young and adult rabbits. RHD is better controlled by vaccination. OBJECTIVE: The current study's goal was to prepare and evaluate the immuno-enhancing effect of montanide ISA70 and aluminum hydroxide (Al(OH)3) gel incorporated within the inactivated RHDV2 vaccine and assess the vaccine's protective efficacy against the homologous and heterologous local RHDV2 strains in rabbits. METHODS: Inactivated RHDV vaccines were prepared using Montanide ISA70 oil or Al(OH)3 gel adjuvants and submitted to sterility, safety, and potency tests. 200 rabbits were equally divided into 4 groups: G1 (control), G2 (vaccinated with gel-incorporated vaccine), G3 (vaccinated with montanide-incorporated vaccine), and G4 (vaccinated with gel- and montanide-incorporated vaccines). Individual blood samples were collected from one week to six months from all groups. The vaccine's potency was measured by the HI test and protection percentage post challenge. RESULTS: Data revealed slightly increasing HI titer means reaching the 1st peak at 4 weeks post-vaccination (7.33, 7.67, and 7.33 log2 in the 2nd, 3rd, and 4th groups, respectively), then slightly decreasing and peaked again, giving 9.33 log2 for the2nd group at 3 months post-vaccination (MPV), 10.67 log2 for 3rd the group, and 10.33 log2 for the 4th group at 5 months post-vaccination. Titer gradually decreased but remained protective. The protection rate ranged from 80-100% and 80-90% for homologous and heterologous local RHDV2 vaccines, respectively, within 3 weeks and 6 months post-challenge. The montanide oil RHDV2 vaccine induced better protection than the aluminum gel RHDV2 vaccine. CONCLUSION: The results demonstrated evidence of cross-protection between RHDV2 strains. The oil emulsion vaccine induced higher and longer-lasting antibody titers than those obtained with the RHDV2 aluminum gel vaccine.

Asunto(s)

Hidróxido de Aluminio , Infecciones por Caliciviridae , Virus de la Enfermedad Hemorrágica del Conejo , Vacunas Virales , Animales , Conejos , Hidróxido de Aluminio/farmacología , Hidróxido de Aluminio/administración & dosificación , Virus de la Enfermedad Hemorrágica del Conejo/inmunología , Vacunas Virales/inmunología , Infecciones por Caliciviridae/veterinaria , Infecciones por Caliciviridae/prevención & control , Geles , Adyuvantes Inmunológicos/farmacología , Adyuvantes Inmunológicos/administración & dosificación , Vacunas de Productos Inactivados/inmunología , Ácidos Oléicos/farmacología , Ácidos Oléicos/administración & dosificación

RESUMEN

Bacterial septicemia represents a significant disease affecting cultured grass carp culture, with the primary etiological agent identified as the Gram-negative bacterium Aeromonas veronii. In response to an outbreak of septicemia in Guangzhou, we developed a formaldehyde-inactivated vaccine against an A. veronii strain designated AV-GZ21-2. This strain exhibited high pathogenicity in experimental infections across at all developmental stages of grass carp. Mortality rates for grass carp weighing 15 ± 5 g ranged from 16 % to 92 % at exposure temperatures of 19 °C-34 °C, respectively. The median lethal dose (LD50) for grass carp groups weighing 15 ± 5 g, 60 ± 10 g, 150 ± 30 g and 500 ± 50 g were determined to be 1.43, 2.52, 4.65 and 7.12 × 107(CFU/mL), respectively. We investigated the inactivated vaccine in conbination with aluminum hydroxide gel (AV-AHG), Montanide ISA201VG (AV-201VG), and white oil (AV-WO) adjuvants. This study aimed to optimize inactivation conditions and identify the adjuvant that elicits the most robust immune response. The AV-GZ21-2 inactivated bacterial solution (AV),when combined with various adjuvants, was capable of inducing a strong specific immune response in grass carp. The relative percent survival (RPS) following a lethal challenge with AV-GZ21-2 were 94 % for AV-AHG, 88 % for AV-201VG, 84 % for AV-WO and 78 % for AV alone. The minimum immunization dose of the AV-AHG vaccine was determined to be 6.0 × 107 CFU per fish, providing immunity for a duration of six months with an immune protection level exceeding 75 %. Furthermore, the AV-AHG vaccine demonstrated significant protective efficacy against various epidemic isolates of A. veronii. Consequently, we developed an inactivated vaccine targeting a highly pathogenic strain of A. veronii, incorporating an aluminum hydroxide gel adjuvant, which resulted in high immune protection and a duration of immunity exceeding six months. These findings suggest that the AV-AHG vaccine holds substantial potential for industrial application.

Asunto(s)

Adyuvantes Inmunológicos , Aeromonas veronii , Vacunas Bacterianas , Carpas , Enfermedades de los Peces , Infecciones por Bacterias Gramnegativas , Vacunas de Productos Inactivados , Animales , Carpas/microbiología , Vacunas Bacterianas/inmunología , Vacunas Bacterianas/administración & dosificación , Vacunas de Productos Inactivados/inmunología , Vacunas de Productos Inactivados/administración & dosificación , Aeromonas veronii/inmunología , Enfermedades de los Peces/prevención & control , Enfermedades de los Peces/microbiología , Enfermedades de los Peces/inmunología , Infecciones por Bacterias Gramnegativas/prevención & control , Infecciones por Bacterias Gramnegativas/veterinaria , Infecciones por Bacterias Gramnegativas/inmunología , Virulencia , Adyuvantes Inmunológicos/administración & dosificación , Dosificación Letal Mediana , Temperatura , China/epidemiología , Hidróxido de Aluminio/administración & dosificación

RESUMEN

We compared the immunogenicity of recombinant S. pneumoniae pneumolysin (rPly) when administered with and without Al(OH)3 adjuvant, and evaluated the protective properties of recombinant protein in the active defense experiment. It was shown that double immunization with rPly+Al(OH)3 increases the levels of IgG antibodies in comparison with the control (p<0.01), while triple immunization results in a more significant increase in IgG antibody levels (p<0.001). Double immunization with rPly without Al(OH)3 does not induce a significant increase in antibody levels in comparison with the control, while triple immunization results in a slight but significant increase in antibody levels (p<0.05). The active defense test proved the protective activity of rPly against S. pneumoniae serotype 3 at intranasal infection.

Asunto(s)

Anticuerpos Antibacterianos , Proteínas Bacterianas , Inmunoglobulina G , Proteínas Recombinantes , Streptococcus pneumoniae , Estreptolisinas , Estreptolisinas/inmunología , Estreptolisinas/genética , Proteínas Bacterianas/inmunología , Proteínas Bacterianas/genética , Streptococcus pneumoniae/inmunología , Streptococcus pneumoniae/genética , Animales , Proteínas Recombinantes/inmunología , Proteínas Recombinantes/genética , Anticuerpos Antibacterianos/inmunología , Anticuerpos Antibacterianos/sangre , Inmunoglobulina G/inmunología , Inmunoglobulina G/sangre , Ratones , Infecciones Neumocócicas/inmunología , Infecciones Neumocócicas/prevención & control , Infecciones Neumocócicas/microbiología , Adyuvantes Inmunológicos , Hidróxido de Aluminio/inmunología , Hidróxido de Aluminio/administración & dosificación , Vacunas Neumococicas/inmunología , Vacunas Neumococicas/administración & dosificación , Femenino

RESUMEN

In this study, a static mixer was used as an alternative to the existing flash mixing method for ballasted flocculation to assess the turbidity removal and ballasted floc formation characteristics. Synthetic magnetite exhibits excellent properties, such as high specific gravity, hydrophobicity, and wear resistance, making it a suitable ballast agent (BA). The experimental design was optimized using the response surface methodology. To evaluate turbidity removal, a model based on polyaluminum chloride dosage, BA surface charge, and pH was developed. To assess the ballasted floc characteristics, the BA dosage, BA size, and G value of the static mixer were used. During ballasted flocculation, the impact of the zeta potential of the BA was minimal. Consequently, bonding primarily resulted from the viscosity of the floc caused by physical collisions rather than electrostatic forces stemming from the BA charge. The findings of this study demonstrated promising outcomes, including potential energy savings and process streamlining, by identifying crucial design elements for implementing a static mixer in the ballasted flocculation process.

Asunto(s)

Óxido Ferrosoférrico , Floculación , Óxido Ferrosoférrico/química , Purificación del Agua/métodos , Hidróxido de Aluminio/química , Interacciones Hidrofóbicas e Hidrofílicas , Eliminación de Residuos Líquidos/métodos , Concentración de Iones de Hidrógeno

RESUMEN

Protein-based subunit vaccines like RBD-Fc are promising tools to fight COVID-19. RBD-Fc fuses the receptor-binding domain (RBD) of the SARS-CoV-2 virus spike protein with the Fc region of human IgG1, making it more immunogenic than RBD alone. Earlier work showed that combining RBD-Fc with iNKT cell agonists as adjuvants improved neutralizing antibodies but did not sufficiently enhance T cell responses, a limitation RBD-Fc vaccines share with common adjuvants. Here we demonstrate that aluminum hydroxide combined with α-C-GC, a C-glycoside iNKT cell agonist, significantly improved the RBD-Fc vaccine's induction of RBD-specific T-cell responses. Additionally, aluminum hydroxide with α-GC-CPOEt, a phosphonate diester derivative, synergistically elicited more robust neutralizing antibodies. Remarkably, modifying αGC with phosphate (OPO3H2) or phosphonate (CPO3H2) to potentially enhance aluminum hydroxide interaction did not improve efficacy over unmodified αGC with aluminum hydroxide. These findings underscore the straightforward yet potent potential of this approach in advancing COVID-19 vaccine development and provide insights for iNKT cell-based immunotherapy.

Asunto(s)

Adyuvantes Inmunológicos , Hidróxido de Aluminio , Anticuerpos Neutralizantes , Anticuerpos Antivirales , Vacunas contra la COVID-19 , COVID-19 , SARS-CoV-2 , Glicoproteína de la Espiga del Coronavirus , Vacunas de Subunidad , Vacunas contra la COVID-19/inmunología , Hidróxido de Aluminio/inmunología , Hidróxido de Aluminio/farmacología , Hidróxido de Aluminio/química , Anticuerpos Neutralizantes/inmunología , Vacunas de Subunidad/inmunología , Adyuvantes Inmunológicos/administración & dosificación , Adyuvantes Inmunológicos/farmacología , Animales , Anticuerpos Antivirales/inmunología , SARS-CoV-2/inmunología , Glicoproteína de la Espiga del Coronavirus/inmunología , COVID-19/prevención & control , COVID-19/inmunología , Ratones , Inmunogenicidad Vacunal , Humanos , Células T Asesinas Naturales/inmunología , Glucolípidos/inmunología , Glucolípidos/química , Femenino , Adyuvantes de Vacunas , Ratones Endogámicos BALB C

RESUMEN

Clay-algae flocculation is a promising method to remove harmful algal blooms (HABs) in aquatic ecosystems. Many HAB-generating species, such as Microcystis aeruginosa (M. aeruginosa), a common species in lakes, produce toxins and harm the environment, human health, and the economy. Natural clays, such as bentonite and kaolinite, and modification of these clays have been applied to mitigate HABs by forming large aggregates and settling down. In this study, we aim to examine the impact of laponite, a commercially available smectite clay that is synthetic, transparent, compatible with human tissues, and degradable, on removing HABs. We compare the cell removal efficiencies (RE) of laponite, two natural clays, and their polyaluminum chloride (PAC)-modified versions through clay-algae flocculation experiments. Our results show that the optimum concentrations of laponite, bentonite, kaolinite, PAC-modified bentonite, and PAC-modified kaolinite to remove 80 % of the M. aeruginosa cells from the water column are 0.05 g/L, 2 g/L, 4 g/L, 2 g/L and 0.3 g/L respectively. Therefore, to achieve the same cell removal efficiency, the amount of laponite needed is 40 to 80 times less than bentonite and kaolinite, and 6 times less than PAC-modified kaolinite. We demonstrate that the superior performance of laponite clay is because of its smaller particle size, which increases the encounter rate between cells and clay particles. Furthermore, experiments using water samples from Powderhorn Lake confirmed laponite's effectiveness in mitigating HABs. Our price analysis also suggests that this commercially-available clay, laponite, can be used in the field at a relatively low cost.

Asunto(s)

Arcilla , Floculación , Microcystis , Arcilla/química , Floraciones de Algas Nocivas , Silicatos/química , Silicatos de Aluminio/química , Caolín/química , Bentonita/química , Hidróxido de Aluminio/química

RESUMEN

To recycle aluminum (Al) from waterworks sludge resulting from polyaluminum chloride (PAC) used as coagulants, this study proposed an innovative strong acidic cation (SAC) exchange resin treatment strategy for Al separation from coexisting fulvic acid (FA) and heavy metals (HMs) in the H2SO4 leachate of PAC sludge. Fluorescence titration confirmed the breakdown of the Al-FA complex at pH 2.0, which facilitated Al separation from FA in the acidic leachate. The species distribution of the dissociated Al (i.e. Ala, Alb, and Alc) significantly influenced the adsorption of Al onto the cation exchange resin. The continuous release of H+ during the cation exchange reaction greatly promoted the transformation of dissociated Alc and Alb into Ala, thereby improving the adsorption of total Al. Moreover, the SAC resin column successfully separated the codissolved HMs from the Al in the leachate even at an influent pH of 2.8, which was attributed to the greater selectivity of the sulfonate groups on the cation exchange resin for free Al3+. The Al eluted from the exhausted resin with 1.1 M H2SO4 was collected as the recycled coagulant after proper pH adjustment. The Al adsorption capacity of the SAC resin decreased by approximately 5 % with each operation cycle and was regained by complete regeneration with 1.8 M H2SO4 after 5 cycles. Overall, the integrated efficiency of Al recovery from PAC sludge by H2SO4 acidification and SAC resin separation/purification reached 70.10 %. The recycled Al from sludge has a water treatment performance comparable to that of fresh PAC coagulant.

Asunto(s)

Hidróxido de Aluminio , Aluminio , Aguas del Alcantarillado , Aguas del Alcantarillado/química , Aluminio/química , Hidróxido de Aluminio/química , Adsorción , Purificación del Agua/métodos , Resinas de Intercambio de Catión/química , Concentración de Iones de Hidrógeno , Reciclaje , Contaminantes Químicos del Agua/química , Benzopiranos/química

RESUMEN

Membrane fouling is a bottleneck issue that hindered the further application of ultrafiltration technology. To alleviate membrane fouling, coagulation-ultrafiltration (C-UF) process using polyaluminum chloride (PACl) and PACl-Al13 with high proportion of Al13O4(OH)247+ as coagulants, respectively, were investigated at various pH conditions. Results indicated that an increase in solution pH contributed to larger floc size and looser floc structure for both PACl and PACl-Al13. It was conducive to the formation of more porous cake, as evidenced by mean pore area and pore area distribution of cake, leading to lower reversible fouling. Furthermore, humic acid (HA) removal presented a trend of first increasing and then decreasing with the increase of pH. The optimal HA removal was achieved at pH 6 regardless of coagulant type, suggesting that the slightest irreversible fouling should be occurred at this point. Interestingly, the irreversible fouling with PACl coagulant achieved a minimum value at pH 9, while the minimal irreversible fouling with PACl-Al13 was observed at pH 6. We speculated that the cake formed by PACl could further intercept HA prior to UF process at alkaline pH. Furthermore, compared with PACl, PACl-Al13 had a stronger charge neutralization ability, thus contributing to more compact floc structure and higher HA removal at various pH conditions. By UF fractionation measurement, higher HA removal for PACl-Al13 was due to higher removal of HA with molecular weight less than 50 kDa.

Asunto(s)

Sustancias Húmicas , Membranas Artificiales , Ultrafiltración , Ultrafiltración/métodos , Sustancias Húmicas/análisis , Floculación , Hidróxido de Aluminio/química , Purificación del Agua/métodos , Concentración de Iones de Hidrógeno , Eliminación de Residuos Líquidos/métodos

RESUMEN

Aluminum hydroxide has long been employed as a vaccine adjuvant for its safety profile, although its precise mechanism of action remains elusive. In this study, we investigated the transcriptomic responses in sheep spleen following repetitive vaccination with aluminum adjuvanted vaccines and aluminum hydroxide alone. Notably, this work represents the first exploration of the sheep spleen transcriptome in such conditions. Animals were splitted in 3 treatment groups: vaccine group, adjuvant alone group and control group. A total of 18 high-depth RNA-seq libraries were sequenced, resulting in a rich dataset which also allowed isoform-level analysis. The comparisons between vaccine-treated and control groups (V vs C) as well as between vaccine-treated and adjuvant-alone groups (V vs A) revealed significant alterations in gene expression profiles, including protein coding genes and long non-coding RNAs. Among the differentially expressed genes, many were associated with processes such as endoplasmic reticulum (ER) stress, immune response and cell cycle. The analysis of co-expression modules further indicated a correlation between vaccine treatment and genes related to ER stress and unfolded protein response. Surprisingly, adjuvant-alone treatment had little impact on the spleen transcriptome. Additionally, the role of alternative splicing in the immune response was explored. We identified isoform switches in genes associated with immune regulation and inflammation, potentially influencing protein function. In conclusion, this study provides valuable insights into the transcriptomic changes in sheep spleen following vaccination with aluminum adjuvanted vaccines and aluminum hydroxide alone. These findings shed light on the molecular mechanisms underlying vaccine-induced immune responses and emphasize the significance of antigenic components in aluminum adjuvant mechanism of action. Furthermore, the analysis of alternative splicing revealed an additional layer of complexity in the immune response to vaccination in a livestock species.

Asunto(s)

Adyuvantes Inmunológicos , Bazo , Transcriptoma , Vacunación , Animales , Bazo/inmunología , Bazo/metabolismo , Ovinos , Perfilación de la Expresión Génica , Vacunas/inmunología , Hidróxido de Aluminio/inmunología , Empalme Alternativo

RESUMEN

Conjugation to carrier proteins is necessary for peptides to be able to induce antibody formation when injected into animals together with a suitable adjuvant. This is usually performed by conjugation in solution followed by mixing with the adjuvant. Alternatively, the carrier may be adsorbed onto a solid support followed by activation and conjugation with the peptide by solid-phase chemistry. Different reagents can be used for conjugation through peptide functional groups (-SH, -NH2, -COOH), and various carrier proteins may be used depending on the peptides and the intended use of the antibodies. The solid phase may be an ion exchange matrix, from which the conjugate can subsequently be eluted and mixed with adjuvant. Alternatively, the adjuvant aluminum hydroxide may be used as the solid-phase matrix, whereupon the carrier is immobilized and conjugated with peptide. The resulting adjuvant-carrier-peptide complexes may then be used directly for immunization.

Asunto(s)

Péptidos , Péptidos/química , Animales , Adyuvantes Inmunológicos/química , Hidróxido de Aluminio/química , Proteínas Portadoras/química , Proteínas Portadoras/metabolismo , Técnicas de Síntesis en Fase Sólida/métodos

RESUMEN

Aluminum salts still remain as the most popular adjuvants in marketed human prophylactic vaccines due to their capability to trigger humoral immune responses with a good safety record. However, insufficient induction of cellular immune responses limits their further applications. In this study, we prepare a library of silicon (Si)- or calcium (Ca)-doped aluminum oxyhydroxide (AlOOH) nanoadjuvants. They exhibit well-controlled physicochemical properties, and the dopants are homogeneously distributed in nanoadjuvants. By using Hepatitis B surface antigen (HBsAg) as the model antigen, doped AlOOH nanoadjuvants mediate higher antigen uptake and promote lysosome escape of HBsAg through lysosomal rupture induced by the dissolution of the dopant in the lysosomes in bone marrow-derived dendritic cells (BMDCs). Additionally, doped nanoadjuvants trigger higher antigen accumulation and immune cell activation in draining lymph nodes. In HBsAg and varicella-zoster virus glycoprotein E (gE) vaccination models, doped nanoadjuvants induce high IgG titer, activations of CD4+ and CD8+ T cells, cytotoxic T lymphocytes, and generations of effector memory T cells. Doping of aluminum salt-based adjuvants with biological safety profiles and immunostimulating capability is a potential strategy to mediate robust humoral and cellular immunity. It potentiates the applications of engineered adjuvants in the development of vaccines with coordinated immune responses.

Asunto(s)

Adyuvantes Inmunológicos , Hidróxido de Aluminio , Calcio , Antígenos de Superficie de la Hepatitis B , Silicio , Adyuvantes Inmunológicos/química , Adyuvantes Inmunológicos/farmacología , Animales , Silicio/química , Ratones , Antígenos de Superficie de la Hepatitis B/inmunología , Antígenos de Superficie de la Hepatitis B/química , Calcio/química , Hidróxido de Aluminio/química , Hidróxido de Aluminio/farmacología , Ratones Endogámicos C57BL , Femenino , Vacunas/inmunología , Vacunas/química , Células Dendríticas/inmunología , Células Dendríticas/efectos de los fármacos , Nanopartículas/química , Humanos , Óxido de Aluminio

RESUMEN

In this work, salicylic acid (SA) was used to induce the self-assembly of octadecyl trimethyl ammonium chloride (OTAC), a cationic surfactant, into three-dimensional wormlike micelle aggregates. These aggregates act as a soft template for hierarchical MgAl hydrotalcite (LDH) to create a multi-level pore structure adsorption material. Scanning electron microscopy characterization showed that the surface of the hierarchical hydrotalcite exhibited a dense layered structure, unlike the monolayer structure of ordinary hydrotalcite. Furthermore, the hierarchical MgAl-LDH possesses a significantly larger specific surface area (113.94 m2/g) and wide pore size distribution ranging more extensively from 2 to 80 nm, which significantly has an impressive adsorption effect on sulfonated lignite (SL), with a maximum adsorption capacity of 192.7 mg/g at pH = 7. Extensive research has been conducted on the adsorption mechanism of hierarchical MgAl-LDH, attributing it to surface adsorption due to the unique multi-level structure of the adsorbent. After two cycles of regeneration experiments, the adsorption capacity of the adsorbent remained at a high level of 179.1 mg/g, demonstrating the excellent renewability of hierarchical MgAl-LDH. Moreover, the hierarchical hydrotalcite showed high adsorption capacity in the adsorption of sulfonated lignite, which was attributed to its larger specific surface area and superior pore structure to expose more active sites.

Asunto(s)

Hidróxido de Aluminio , Hidróxido de Magnesio , Hidróxido de Aluminio/química , Hidróxido de Magnesio/química , Adsorción

RESUMEN

Easy synthesis of efficient, non-toxic photocatalysts is a target to expand their potential applications. In this research, the role of Eu3+ doping in the non-toxic, affordable, and easily prepared MgAl hydrotalcite-like compounds (HTlcs) was explored in order to prepare visible light semiconductors. Eu doped MgAl-HTlcs (MA-xEu) samples were prepared using a simple coprecipitation method (water, room temperature and atmospheric pressure) and europium was successfully incorporated into MgAl HTlc frameworks at various concentrations, with x (Eu3+/M3+ percentage) ranging from 2 to 15. Due to the higher ionic radius and lower polarizability of Eu3+ cation, its presence in the metal hydroxide layer induces slight structural distortions, which eventually affect the growth of the particles. The specific surface area also increases with the Eu content. Moreover, the presence of Eu3+ 4f energy levels in the electronic structure enables the absorption of visible light in the doped MA-xEu samples and contributes to efficient electron-hole separation. The microstructural and electronic changes induced by the insertion of Eu enable the preparation of visible light MgAl-based HTlcs photocatalysts for air purification purposes. Specifically, the optimal HTlc photocatalyst showed improved NOx removal efficiency, ∼ 51% (UV-Vis) and 39% (visible light irradiation, 420 nm), with excellent selectivity (> 96 %), stability (> 7 h), and enhanced release of •O2- radicals. Such results demonstrate a simple way to design photocatalytic HTlcs suitable for air purification technologies.

Asunto(s)

Hidróxido de Aluminio , Europio , Hidróxido de Magnesio , Óxidos de Nitrógeno , Oxidación-Reducción , Europio/química , Catálisis , Hidróxido de Magnesio/química , Hidróxido de Aluminio/química , Óxidos de Nitrógeno/química , Procesos Fotoquímicos , Luz , Contaminantes Atmosféricos/química

RESUMEN

BACKGROUND: The achievement of optimal vaccine efficacy is contingent upon the collaborative interactions between T and B cells in adaptive immunity. Although multiple immunization strategies have been proposed, there is a notable scarcity of comprehensive investigations pertaining to enhance immune effects through immune strategy adjustments for individual vaccine. METHODS: The hierarchically structured aluminum hydroxide microgel-stabilized Pickering emulsion (ASPE) was prepared by ultrasonic method. This study explored the influence of the immune strategy of ASPE to immune responses, including antigen exposure pattern, adjuvants and antigen dosage, and administration interval. RESULTS: The findings revealed that external antigen adsorption facilitated increased exposure of antigen epitopes, leading to elevated IgG titers and secretion of cytokines such as interferon-gamma (IFN-γ) or interleukin-4 (IL-4). Additionally, even a low dose (1 µg/dose) of antigens of ASPE boosted sufficient neutralizing antibody levels and memory T cells compared to high-dose antigens, which consistent with the adjuvant dosage effect. Furthermore, maintaining a 4-week immunization interval yielded optimal levels of antigen-specific IgG titers in both short-term and long-term scenarios, as compared to intervals of 2, 3, and 5 weeks. A consistent trend was observed in the proliferation of memory B cells, reaching a superior level at the 4-week interval, which could enhance protection against viral re-infection. CONCLUSION: Tailoring immunization strategies for specific vaccines has emerged as powerful driver in maximizing vaccine efficacy and eliciting robust immune responses, thereby presenting cutting-edge approaches to enhanced vaccination.

Asunto(s)

Adyuvantes Inmunológicos , Emulsiones , Inmunoglobulina G , Animales , Ratones , Inmunoglobulina G/sangre , Inmunoglobulina G/inmunología , Adyuvantes Inmunológicos/administración & dosificación , Femenino , Eficacia de las Vacunas , Anticuerpos Neutralizantes/inmunología , Anticuerpos Neutralizantes/sangre , Compuestos de Alumbre/administración & dosificación , Ratones Endogámicos BALB C , Linfocitos B/inmunología , Interferón gamma/inmunología , Interleucina-4/inmunología , Adyuvantes de Vacunas/administración & dosificación , Hidróxido de Aluminio/inmunología , Hidróxido de Aluminio/administración & dosificación , Linfocitos T/inmunología , Células T de Memoria/inmunología , Citocinas/inmunología

RESUMEN

Layered double hydroxides (LDH) have been shown to be effective adsorbents, but their utility for the treatment of per- and polyfluoroalkyl substances (PFAS) in water has not been fully explored. In this study, the adsorption of 9 PFAS on hydrotalcite (HT), a type of LDH, was investigated using reaction solutions with environmentally relevant PFAS concentrations. The adsorption of individual PFAS by HT depended upon a range of factors, including the temperature used to pre-treat (i.e., calcine) the HT, aging conditions, and the presence of anions in the solution. HT calcined near 400 °C most effectively adsorbed PFAS, but its ability to adsorb PFAS was sensitive to storage conditions. The adsorption of CO2 and moisture from air, which likely resulted in the re-intercalation of CO32- into the interlayer regions of HT, was observed to reduce PFAS adsorption and may explain performance loss over time. The adsorption trend among 9 PFAS and the influence on this process by Cl-, NO3-, SO42-, and CO32- indicated that adsorption occurred via a combination of ion exchange, electrostatic attraction, and hydrophobic interactions, although the relative importance of each mechanism deserves further investigation. During this study, we also demonstrated for the first time that HT can be thermally regenerated at 400 °C without affecting its ability to adsorb PFOS and PFBA. Overall, our results suggest that HT may serve as an effective alternative for PFAS treatment.

Asunto(s)

Hidróxido de Aluminio , Fluorocarburos , Hidróxido de Magnesio , Contaminantes Químicos del Agua , Adsorción , Hidróxido de Magnesio/química , Hidróxido de Aluminio/química , Fluorocarburos/química , Contaminantes Químicos del Agua/química , Purificación del Agua/métodos , Temperatura

RESUMEN

This study presents the successful synthesis of Magnesium-aluminum layered double hydroxide composite phosphate-modified hydrothermal biochar for efficient removal of U(VI) from aqueous solutions. A novel synthesis approach involving phosphate thermal polymerization-hydrothermal method was employed, deviating from conventional pyrolysis methods, to produce hydrothermal biochar. The combination of solvent thermal polymerization technique with hydrothermal process facilitated efficient loading of layered double hydroxide (LDH) components onto the biochar surface, ensuring simplicity, low energy consumption and enhanced modifiability. Bamboo waste was utilized as the precursor for biochar, highlighting its superior green and sustainable characteristics. Additionally, this study elucidated the interactions between phosphate-modified hydrothermal biochar and LDH components with U(VI). Physicochemical analysis demonstrated that the composite biochar possessed a high surface area and abundant oxygen-containing functional groups. XPS and FTIR analyses confirmed the efficient adsorption of U(VI), attributed to chelation interactions between phosphate groups, magnesium hydroxyl groups, hydroxyl groups and U(VI), as well as the co-precipitation of U(VI) with multi-hydroxyl aluminum cations captured by LDH. The composite biochar reached adsorption equilibrium with U(VI) within 80 min and exhibited excellent fitting to the pseudo-second-order kinetic model and Langmuir model. Under conditions of pH = 4 and 298 K, it displayed significantly high maximum adsorption capacity of approximately 388.81 mg g⁻1, surpassing untreated biochar by 17-fold. The adsorption process was found to be endothermic and spontaneous and even after five consecutive adsorption-desorption cycles, the removal efficiency of U(VI) remained stable at 75.46%. These findings underscore the promising application prospects of Magnesium-aluminum layered double hydroxide composite phosphate-modified hydrothermal biochar in efficiently separating U(VI) from uranium-containing wastewater, emphasizing its environmental and economic value.

Asunto(s)

Carbón Orgánico , Hidróxidos , Magnesio , Fosfatos , Uranio , Carbón Orgánico/química , Adsorción , Uranio/química , Fosfatos/química , Magnesio/química , Hidróxidos/química , Aluminio/química , Cinética , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/análisis , Hidróxido de Aluminio/química

RESUMEN

The development of high-purity antigens promotes the urgent need of novel adjuvant with the capability to trigger high levels of immune response. Polyinosinic-polycytidylic (Poly(I:C)) is a synthetic double-stranded RNA (dsRNA) that can engage Toll-like receptor 3 (TLR3) to initiate immune responses. However, the Poly(I:C)-induced toxicity and inefficient delivery prevent its applications. In our study, combination adjuvants are formulated by aluminum oxyhydroxide nanorods (AlOOH NRs) and Poly(I:C), named Al-Poly(I:C), and the covalent interaction between the two components is further demonstrated. Al-Poly(I:C) mediates enhanced humoral and cellular immune responses in three antigen models, i.e., HBsAg virus-like particles (VLPs), human papilloma virus (HPV) VLPs and varicella-zoster virus (VZV) glycoprotein E (gE). Further mechanistic studies demonstrate that the dose and molecular weight (MW) of Poly(I:C) determine the physicochemical properties and adjuvanticity of the Al-Poly(I:C) combination adjuvants. Al-Poly(I:C) with higher Poly(I:C) dose promotes antigen-bearing dendritic cells (DCs) recruitment and B cells proliferation in lymph nodes. Al-Poly(I:C) formulated with higher MW Poly(I:C) induces higher activation of helper T cells, B cells, and CTLs. This study demonstrates that Al-Poly(I:C) potentiates the humoral and cellular responses in vaccine formulations. It offers insights for adjuvant design to meet the formulation requirements in both prophylactic and therapeutic vaccines.

Asunto(s)

Adyuvantes Inmunológicos , Poli I-C , Poli I-C/administración & dosificación , Poli I-C/farmacología , Animales , Adyuvantes Inmunológicos/administración & dosificación , Adyuvantes Inmunológicos/farmacología , Adyuvantes Inmunológicos/química , Femenino , Ratones Endogámicos C57BL , Hidróxido de Aluminio/administración & dosificación , Hidróxido de Aluminio/química , Nanotubos/química , Inmunidad Humoral/efectos de los fármacos , Antígenos de Superficie de la Hepatitis B/inmunología , Antígenos de Superficie de la Hepatitis B/administración & dosificación , Humanos , Ratones , Inmunidad Celular/efectos de los fármacos , Ratones Endogámicos BALB C , Vacunas/administración & dosificación , Vacunas/inmunología , Óxido de Aluminio

RESUMEN

Whole virus-based inactivated SARS-CoV-2 vaccines adjuvanted with aluminum hydroxide have been critical to the COVID-19 pandemic response. Although these vaccines are protective against homologous coronavirus infection, the emergence of novel variants and the presence of large zoonotic reservoirs harboring novel heterologous coronaviruses provide significant opportunities for vaccine breakthrough, which raises the risk of adverse outcomes like vaccine-associated enhanced respiratory disease. Here, we use a female mouse model of coronavirus disease to evaluate inactivated vaccine performance against either homologous challenge with SARS-CoV-2 or heterologous challenge with a bat-derived coronavirus that represents a potential emerging disease threat. We show that inactivated SARS-CoV-2 vaccines adjuvanted with aluminum hydroxide can cause enhanced respiratory disease during heterologous infection, while use of an alternative adjuvant does not drive disease and promotes heterologous viral clearance. In this work, we highlight the impact of adjuvant selection on inactivated vaccine safety and efficacy against heterologous coronavirus infection.

Asunto(s)

Hidróxido de Aluminio , Vacunas contra la COVID-19 , COVID-19 , SARS-CoV-2 , Vacunas de Productos Inactivados , Animales , Vacunas contra la COVID-19/inmunología , Vacunas contra la COVID-19/administración & dosificación , Femenino , COVID-19/prevención & control , COVID-19/inmunología , COVID-19/virología , Ratones , Vacunas de Productos Inactivados/inmunología , SARS-CoV-2/inmunología , Hidróxido de Aluminio/administración & dosificación , Modelos Animales de Enfermedad , Adyuvantes Inmunológicos/administración & dosificación , Adyuvantes de Vacunas , Anticuerpos Antivirales/inmunología , Ratones Endogámicos BALB C , Humanos , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo/inmunología

RESUMEN

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.

Asunto(s)

Diferenciación Celular , Nanopartículas , Células-Madre Neurales , Diferenciación Celular/efectos de los fármacos , Animales , Células-Madre Neurales/efectos de los fármacos , Células-Madre Neurales/citología , Células-Madre Neurales/metabolismo , Ratones , Nanopartículas/química , Metilación/efectos de los fármacos , Hidróxidos/química , Hidróxidos/farmacología , Metiltransferasas/metabolismo , Metiltransferasas/genética , Tamaño de la Partícula , Células Madre Embrionarias/efectos de los fármacos , Células Madre Embrionarias/citología , Adenosina/farmacología , Adenosina/química , Adenosina/análogos & derivados , Hidróxido de Aluminio/química , Hidróxido de Aluminio/farmacología , Hidróxido de Magnesio/química , Hidróxido de Magnesio/farmacología