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IScience Jun 2024While photocatalytic technology has brought additional opportunities and possibilities for the green conversion and sustainable development of ammonium-based nitrogen...
While photocatalytic technology has brought additional opportunities and possibilities for the green conversion and sustainable development of ammonium-based nitrogen fertilizers, the low activation efficiency of the molecular N has impeded its further application feasibility. Here to address the concern, we designed an amorphous molybdenum hydroxide anchored on the ultrathin magnesium-aluminum layered double hydroxide (Mo@MgAl-LDH) nanosheets for benefiting the N photofixation to NH. With the aid of the designed amorphous Mo(V) species, the pristine MgAl-LDH exhibited a considerable performance of nitrogen photofixation under visible light irradiation (NH production rate of 114.4 μmol g h) due to the improved N activation efficiency. The work demonstrated a feasible strategy for nitrogen photofixation using amorphous Mo(V) species, which may also deliver a novel inspiration for the development of amorphous photocatalysts toward the photoactivation of molecular N.
PubMed: 38947498
DOI: 10.1016/j.isci.2024.110088 -
Environmental Science and Pollution... Jun 2024Red mud is a highly alkaline solid waste discharged from the alumina industry, and its high sodium content is the key factor limiting its wide utilization. Therefore,...
Red mud is a highly alkaline solid waste discharged from the alumina industry, and its high sodium content is the key factor limiting its wide utilization. Therefore, effective control of the "frosting" phenomenon during the application of red mud has received significant attention. In this study, the changes of particle size, phase, morphology, and pore size of red mud after sodium removal with different amounts of citric acid pretreatment were investigated. The single-factor experiment shows that the Na leaching rate is 86.33% under a citric acid dosage of 15%, liquid-to-solid ratio of 7 mL/g, leaching temperature of 80 °C, stirring speed of 300 rpm, and leaching time of 10 min. The leachate is characterized through X-ray diffraction (XRD), scanning electron microscopy (SEM), and Brunauer-Emmett-Teller (BET) surface area analysis. The results reveal that Na mainly exists in a combined state in the form of cancrinite. With the increase of citric acid dosage, red mud agglomerates, calcite, and cancrinite are dissolved, and new phases such as calcium oxalate and magnesium aluminum hydroxide are formed. The specific surface area, pore volume, and pore diameter show irregular changes with the increase in the citric acid dosage. Citric acid pretreatment can effectively reduce the sodium content in red mud, the treatment cost of leaching solution is low, and the leaching residue is neutral, which is helpful to promote the practical application of red mud.
PubMed: 38937355
DOI: 10.1007/s11356-024-33850-5 -
Vaccines Jun 2024Particulate aluminum salts have long occupied a central place worldwide as inexpensive immunostimulatory adjuvants that enable induction of protective immunity for...
Particulate aluminum salts have long occupied a central place worldwide as inexpensive immunostimulatory adjuvants that enable induction of protective immunity for vaccines. Despite their huge benefits and safety, the particulate structures of aluminum salts require transportation and storage at temperatures between 2 °C and 8 °C, and they all have exquisite sensitivity to damage caused by freezing. Here, we propose to solve the critical freezing vulnerability of particulate aluminum salt adjuvants by introducing soluble aluminum salts as adjuvants. The solubility properties of fresh and frozen aluminum chloride and aluminum triacetate, each buffered optimally with sodium acetate, were demonstrated with visual observations and with UV-vis scattering analyses. Two proteins, A244 gp120 and CRM, adjuvanted either with soluble aluminum chloride or soluble aluminum triacetate, each buffered by sodium acetate at pH 6.5-7.4, elicited murine immune responses that were equivalent to those obtained with Alhydrogel, a commercial particulate aluminum hydroxide adjuvant. The discovery of the adjuvanticity of soluble aluminum salts might require the creation of a new adjuvant mechanism for aluminum salts in general. However, soluble aluminum salts might provide a practical substitute for particulate aluminum salts as vaccine adjuvants, thereby avoiding the risk of inactivation of vaccines due to accidental freezing of aluminum salt particles.
PubMed: 38932410
DOI: 10.3390/vaccines12060681 -
Vaccines May 2024An incomplete Freund's adjuvant elicited an overt pathogenesis in vaccinated mice following the intranasal challenge of A/California/07/2009 (H1N1) virus despite the...
An incomplete Freund's adjuvant elicited an overt pathogenesis in vaccinated mice following the intranasal challenge of A/California/07/2009 (H1N1) virus despite the induction of a higher specific antibody titer than other adjuvanted formulations. Aluminum hydroxide adjuvants have not induced any pathogenic signs in a variety of formulations with glycolipids. A glycolipid, α-galactosyl ceramide, improved a stimulatory effect of distinct adjuvanted formulations on an anti-influenza A antibody response. In contrast to α-galactosyl ceramide, its synthetic analogue C34 was antagonistic toward a stimulatory effect of an aluminum hydroxide adjuvant on a specific antibody response. The aluminum hydroxide adjuvant alone could confer complete vaccine-induced protection against mortality as well as morbidity caused by a lethal challenge of the same strain of an influenza A virus. The research results indicated that adjuvants could reshape immune responses either to improve vaccine-induced immunity or to provoke an unexpected pathogenic consequence. On the basis of these observations, this research connotes the prominence to develop a precision adjuvant for innocuous vaccination aimed at generating a protective immunity without aberrant responses.
PubMed: 38932298
DOI: 10.3390/vaccines12060569 -
International Journal of Molecular... Jun 2024Cobalt-aluminum-layered double hydroxides containing carboxymethyl β-cyclodextrin (CMβCD) were synthesized by coprecipitation and evaluated as a cobalt source for the...
Cobalt-aluminum-layered double hydroxides containing carboxymethyl β-cyclodextrin (CMβCD) were synthesized by coprecipitation and evaluated as a cobalt source for the 4-nitrophenol reduction in an aqueous medium. Several physicochemical techniques (XRD, FTIR, TGA) indicated the intercalation of the anionic cyclodextrin without damages to the hydrotalcite-type structure. These lamellar cobalt-aluminum hybrid materials (CoAl_CMβCD) were evaluated in the 4-nitrophenol reduction and showed higher activities in comparison with the CMβCD-free standard material (CoAl_CO). To rationalize these results, a set of experimental controls going from physical mixtures of CoAl_CO with different cyclodextrins to other cobalt-based materials were investigated, highlighting the beneficial effects of both the layered double hydroxide and CMβCD-based hybrid structures. CMβCD also showed a beneficial effect as an additive during the 4-nitrophenol reduction. CoAl_CO, dispersed in a fresh CMβCD solution could be re-used for five successive cycles without the loss of activity.
Topics: Nitrophenols; Cobalt; beta-Cyclodextrins; Hydroxides; Oxidation-Reduction; Catalysis; X-Ray Diffraction; Spectroscopy, Fourier Transform Infrared
PubMed: 38928099
DOI: 10.3390/ijms25126390 -
Zhongguo Dang Dai Er Ke Za Zhi =... Jun 2024To explore the effects of iris xanthin on airway inflammation, airway remodeling, and the high mobility group box 1 protein (HMGB1)/Toll-like receptor 4 (TLR4)/nuclear...
OBJECTIVES
To explore the effects of iris xanthin on airway inflammation, airway remodeling, and the high mobility group box 1 protein (HMGB1)/Toll-like receptor 4 (TLR4)/nuclear factor-κB (NF-κB) pathway in asthmatic young mice.
METHODS
Sixty male BALB/c young mice were randomly assigned into six groups: a blank group, a model group, a dexamethasone group, and low, medium, and high dose groups of iris xanthin, with ten mice per group. Asthma models were induced through intraperitoneal injections of a sensitizing agent [ovalbumin (OVA) 20 μg + aluminum hydroxide gel 2 mg], followed by 4% OVA aerosol inhalation. Lung function was measured using a pulmonary function tester to determine lung volume (LV), resting ventilation per minute (VE), and airway reactivity (Penh value). Hematoxylin-eosin (HE) staining was employed to examine and analyze airway remodeling. The contents of interleukin (IL)-1β, IL-6, and tumor necrosis factor alpha (TNF-α) in bronchoalveolar lavage fluid were quantified using ELISA. Real-time fluorescence quantitative polymerase chain reaction and Western blot analysis were used to assess the expression of HMGB1/TLR4/NF-κB pathway-related mRNA and proteins in lung tissues.
RESULTS
Compared to the model group, the dexamethasone and iris xanthin-treated groups (low, medium, and high doses) exhibited significant increases in LV and VE (<0.05), with incremental dose-dependent increases observed in the iris xanthin groups. Additionally, Penh values, IL-1β, IL-6, TNF-α, and airway remodeling indicators, along with mRNA levels of HMGB1, TLR4, and NF-κB p65 and protein levels of HMGB1, TLR4, and p-NF-κB p65, were all reduced (<0.05) in a dose-dependent manner. When compared to the dexamethasone group, the low and medium dose iris xanthin groups showed decreases in LV and VE (<0.05), whereas Penh values, IL-1β, IL-6, TNF-α, and airway remodeling indicators, along with mRNA levels of HMGB1, TLR4, NF-κB p65 and protein levels of HMGB1, TLR4, and p-NF-κB p65, were increased (<0.05). No significant differences were noted in these indices between the high dose iris xanthin group and the dexamethasone group (>0.05).
CONCLUSIONS
Iris xanthin can effectively alleviates airway inflammation and inhibits airway remodeling in asthmatic young mice, possibly through the suppression of the HMGB1/TLR4/NF-κB pathway.
Topics: Animals; Airway Remodeling; Asthma; Male; Mice; Toll-Like Receptor 4; Mice, Inbred BALB C; HMGB1 Protein; NF-kappa B; Signal Transduction
PubMed: 38926382
DOI: 10.7499/j.issn.1008-8830.2312023 -
Chemosphere Jun 2024This study presents the successful synthesis of Magnesium-aluminum layered double hydroxide composite phosphate-modified hydrothermal biochar for efficient removal of...
Efficient enrichment of uranium (VI) in aqueous solution using magnesium-aluminum layered double hydroxide composite phosphate-modified hydrothermal biochar: Mechanism and adsorption.
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⁻, 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.
PubMed: 38906190
DOI: 10.1016/j.chemosphere.2024.142667 -
Vaccine Jun 2024The achievement of optimal vaccine efficacy is contingent upon the collaborative interactions between T and B cells in adaptive immunity. Although multiple immunization...
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.
PubMed: 38876839
DOI: 10.1016/j.vaccine.2024.05.070 -
ACS Applied Materials & Interfaces Jun 2024Minimally invasive embolization greatly decreases the mortality resulting from vascular injuries while still suffering from a high risk of recanalization and systematic...
Minimally invasive embolization greatly decreases the mortality resulting from vascular injuries while still suffering from a high risk of recanalization and systematic thrombosis due to the intrinsic hydrophobicity and poor adhesion of the clinically used liquid embolic agent of Lipiodol. In this study, a shape self-adaptive liquid embolic agent was developed by mixing biocompatible poly(acrylic acid) (PAA), two-dimensional magnesium-aluminum layered double hydroxide (LDH), and poly(ethylene glycol)200 (PEG200). Upon contact with blood, the injectable PAA-LDH@PEG200 would quickly absorb water to form an adhesive and mechanically strong PAA-LDH thin hydrogel within 5 s, which could firmly adhere to the blood vessel wall for ultrafast and durable embolization. In addition, benefiting from the "positively charged nucleic center effect" of LDH nanosheets, the liquid PAA-LDH@PEG200 could avoid vascular distension by PAA overexpansion and possess high shock-resistant mechanical strength from the blood flow. Furthermore, both in vitro and in vivo embolization experiments demonstrated the complete embolic capacity of liquid PAA-LDH@PEG200 without the occurrence of recanalization for 28 days and also the great potential to act as a platform to couple with chemotherapeutic drugs for the minimized transcatheter arterial chemoembolization (TACE) treatment of VX2 tumors without recurrence for 18 days. Thus, liquid PAA-LDH@PEG200 developed here possesses great potential to act as a shape self-adaptive liquid embolic agent for ultrafast and durable vascular embolization.
Topics: Animals; Polyethylene Glycols; Mice; Acrylic Resins; Embolization, Therapeutic; Humans; Hydroxides; Hydrogels; Aluminum
PubMed: 38869429
DOI: 10.1021/acsami.4c02892 -
Biomedical Optics Express Jun 2024Adjuvants are indispensable ingredients in vaccine formulations. Evaluating the in vivo transport processes of adjuvants, particularly for inhalation formulations,...
Adjuvants are indispensable ingredients in vaccine formulations. Evaluating the in vivo transport processes of adjuvants, particularly for inhalation formulations, presents substantial challenges. In this study, a nanosized adjuvant aluminum hydroxide (AlOOH) was synthesized and labeled with indocyanine green (ICG) and bovine serum albumin (BSA) to achieve strong optical absorption ability and high biocompatibility. The adjuvant nanomaterials (BSA@ICG@AlOOH, BIA) were delivered as an aerosol into the airways of mice, its distribution was monitored using photoacoustic imaging (PAI) in vivo. PAI results illustrated the gradual cross-layer transmission process of BIA in the tracheal layer, traversing approximately 250 µm from the inner layer of the trachea to the outer layer. The results were consistent with pathology. While the intensity of the BIA reduced by approximately 46.8% throughout the transport process. The ability of PAI for quantitatively characterized the dynamic transport process of adjuvant within the tracheal layer may be widely used in new vaccine development.
PubMed: 38867767
DOI: 10.1364/BOE.527912