Sodium Sulfate Research Articles

Sulforaphane decreases oxidative stress and inhibits NLRP3 inflammasome activation in a mouse model of ulcerative colitis

Excessive oxidative stress and NLRP3 inflammasome activation are considered the main drivers of inflammatory bowel disease (IBD), and inhibition of inflammasomes ameliorates clinical symptoms and morphological manifestations of IBD. Herein, we examined the roles of NLRP3 activation in IBD and modulation of NLRP3 by sulforaphane (SFN), a compound with multiple pharmacological activities that is extracted from cruciferous plants. To simulate human IBD, we established a mouse colitis model by administering dextran sodium sulfate in the drinking water. SFN (25, 50 mg·kg−1·d−1, ig) or the positive control sulfasalazine (500 mg/kg, ig) was administered to colitis-affected mice for 7 days. Model mice displayed pathological alterations in colon tissue as well as classic symptoms of colitis beyond substantial tissue inflammation. Expression of NLRP3, ASC, and caspase-1 was significantly elevated in the colonic epithelium. The expression of NLRP3 inflammasomes led to activation of downstream proteins and increases in the cytokines IL-18 and IL-1β. SFN administration either fully or partially reversed these changes, thus restoring IL-18 and IL-1β, substantially inhibiting NLRP3 activation, and decreasing inflammation. SFN alleviated the inflammation induced by LPS and NLRP3 agonists in RAW264.7 cells by decreasing the levels of reactive oxygen species. In summary, our results revealed the pathological roles of oxidative stress and NLRP3 in colitis, and indicated that SFN might serve as a natural NLRP3 inhibitor, thereby providing a new strategy for alternative colitis treatment.

Valorization of agitated thin film dryer (ATFD)-mixed-salt from textile wastewater for its application in leather manufacturing – a sustainable approach

ABSTRACT The textile industry uses sodium chloride and sodium sulphate during the dyeing process to improve the fixation of dyes on fabrics. After wastewater treatment, the reject stream is dried resulting in mixed salts as solid wastes that are not reused. The leather industry also uses a vast quantity of salt for temporary preservation of skins/hides and as swelling-suppressing agent during the pickling (acidification) process. Thus, an attempt was made to utilize the mixed salt obtained from the textile industry to replace sodium chloride in leather processing. It was found that a 40% w/w offer of ATFD salt was able to preserve the skins for 3 months, which was on par with the preservation carried out using a similar quantity of sodium chloride in conventional preservation process. Likewise, for the pickling process, an offer of 10% w/w ATFD salt provided sufficient deswelling action when compared to conventionally used sodium chloride. However, the residual colour of the mixed salts affected the quality of the leather obtained. To overcome this, an electro-oxidation treatment was carried out to obtain decolourized salts. The COD measurements showed that the 1% solution of ATFD-3 salt reduced from 471 ± 25 to 88 ± 16 ppm. A similar trend was also seen in BOD reduction from 80 ± 12 to 18 ± 10 ppm. These results confirmed that the colour removal could be due to the degradation of the organic contaminants present in the ATFD salt. Thus, the treated ATFD salt can be reused for leather processing without affecting leather quality, thus promoting the concept of circular economy.

Qingzhuan dark tea polysaccharides-zinc alleviates dextran sodium sulfate-induced ulcerative colitis.

Qingzhuan dark tea polysaccharides (QDTP) have been complexed with Zinc (Zn) to form the Qingzhuan dark tea polysaccharides-Zinc (QDTP-Zn) complex. The present study investigated the protective effects of QDTP-Zn on ulcerative colitis (UC) in mice. The UC mouse model was induced using dextran sodium sulfate (DSS), followed by oral administration of QDTP-Zn (0.2 and 0.4 g kg-1 day-1). QDTP-Zn demonstrated alleviation of UC symptoms in mice, as evidenced by a decrease in disease activity index scores. QDTP-Zn also regulated colon tissue injury by upregulating ZO-1 and occludin protein expression, at the same time as downregulating tumor necrosis factor-α and interleukin-6β levels. Furthermore, QDTP-Zn induced significant alterations in the abundance of bacteroidetes and firmicutes and notably increased levels of short-chain fatty acids (SCFAs), particularly acetic acid, propionic acid, and butyric acid. In summary, QDTP-Zn exhibits therapeutic potential in alleviating enteritis by fortifying the colonic mucosal barrier, mitigating inflammation and modulating intestinal microbiota and SCFAs levels. Thus, QDTP-Zn holds promise as a functional food for both the prevention and treatment of UC. © 2024 Society of Chemical Industry.

Pore structure evolution and adsorption behaviors of porous poly (vinyl alcohol) hydrogel prepared using Na2SO4 and CaCO3 as porogens

AbstractIn this work, porous poly (vinyl alcohol) (PVA) hydrogels with different pore sizes were fabricated using inorganic non‐metallic porogens by an environmentally friendly method, providing a potential solution for the field of wastewater treatment. PVA hydrogels have gained much attention in the field of wastewater treatment due to their excellent adsorption performance and porous network structure. However, the employment of inorganic non‐metallic salts as porogens for PVA hydrogels has received limited attention so far. In this study, porous PVA hydrogels were prepared by freeze‐thawing and freeze‐drying with sodium sulfate (Na2SO4) and calcium carbonate (CaCO3) as porogens. PVA‐Na exhibited denser network structure with the concentration of Na2SO4 solution increased, and the tensile stress was enhanced by about 45 times. Meanwhile, the tensile stress of PVA‐Ca was improved significantly from 0.06 to 1.67 MPa, and the network structure became looser after adding CaCO3. Moreover, a comprehensive investigation was conducted on the adsorption performance of porous PVA hydrogel for Congo red (CR). Finally, five adsorption models were fitted to investigate the adsorption mechanism of porous PVA hydrogels, in which the maximum adsorption capacity of CR by PVA‐Na‐0.5 was predicted to be 215 mg/g by the Langmuir isothermal model fitting.Highlights The structure of PVA hydrogels was adjusted by Na2SO4 and CaCO3, respectively. The tensile stress of PVA‐Na with dense network structure increased 45 times. Compared to PVA‐FD, swelling equilibrium time of PVA‐Na reduced from 24 to 6 h. Equilibrium swelling rate of PVA‐Ca declined by half in comparison to PVA‐FD. Langmuir isothermal model predicted qmax of 215 mg/g for CR by PVA‐Na‐0.5.

Ace Deficiency Induces Intestinal Inflammation in Zebrafish

Inflammatory bowel disease (IBD) is a nonspecific chronic inflammatory disease resulting from an immune disorder in the intestine that is prone to relapse and incurable. The understanding of the pathogenesis of IBD remains unclear. In this study, we found that ace (angiotensin-converting enzyme), expressed abundantly in the intestine, plays an important role in IBD. The deletion of ace in zebrafish caused intestinal inflammation with increased expression of the inflammatory marker genes interleukin 1 beta (il1b), matrix metallopeptidase 9 (mmp9), myeloid-specific peroxidase (mpx), leukocyte cell-derived chemotaxin-2-like (lect2l), and chemokine (C-X-C motif) ligand 8b (cxcl8b). Moreover, the secretion of mucus in the ace−/− mutants was significantly higher than that in the wild-type zebrafish, validating the phenotype of intestinal inflammation. This was further confirmed by the IBD model constructed using dextran sodium sulfate (DSS), in which the mutant zebrafish had a higher susceptibility to enteritis. Our study reveals the role of ace in intestinal homeostasis, providing a new target for potential therapeutic interventions.

A comprehensive understanding of the role of sodium sulfate in calcium looping via in-situ experiments and DFT studies: Performance and mechanism

Adding alkali metal salt promoters to calcium-based materials can influence the cycling performance of CaO-based sorbents. So far, most research on alkali metal salts focus on carbonate and chloride salts, while little attention is paid to sulfates. In this paper, we present an in-depth study of the role of Na2SO4 in calcium looping via in-situ experiments and DFT simulations. The results show that the effective conversion rate of Na2SO4-CaO after one cycle is 0.779 with the energy storage density of 2476.1 kJ/kg, while the effective conversion rate of CaO is 0.562 with the energy storage density of 1786.4 kJ/kg. After 80 cycles, the effective conversion and energy storage density of Na2SO4-CaO are lower than CaO, which is attributed to Na+ reducing the surface energy and accelerating the sintering. Moreover, an optimization strategy based on coordination effect among Na2SO4, CaO and inert oxides is proposed to slow down the sintering problems. Among them, Na2SO4-(CaO + ZnO) has the best adsorption performance and energy storage performance and ZnO is cheap, which can be considered a cost-effective sorbent. This work provides a new approach for developing efficient, simple and cost-effective calcium-based materials by simultaneously achieving fast reaction rates and good cycling stability of CaL.

Activation Behavior and Mechanism of Sodium Sulfate for Iron Recovery from Red Mud through Magnetization Roasting–Magnetic Separation

Activation Behavior and Mechanism of Sodium Sulfate for Iron Recovery from Red Mud through Magnetization Roasting–Magnetic Separation

Influence of Carboxymethyl Cellulose as a Thickening Agent for Glauber's Salt-Based Low Temperature PCM.

This work is focused on a novel, promising low temperature phase change material (PCM), based on the eutectic Glauber's salt composition. To allow phase transition within the refrigeration range of temperatures of +5 °C to +12 °C, combined with a high repeatability of melting-freezing processes, and minimized subcooling, the application of three variants of sodium carboxymethyl cellulose (Na-CMC) with distinct molecular weights (700,000, 250,000, and 90,000) is considered. The primary objective is to optimize the stabilization of this eutectic PCM formulation, while maintaining the desired enthalpy level. Preparation methods are refined to ensure repeatability in mixing components, thereby optimizing performance and stability. Additionally, the influence of Na-CMC molecular weight on stabilization is examined through differential scanning calorimetry (DSC), T-history, and rheology tests. The PCM formulation of interest builds upon prior research in which borax, ammonium chloride, and potassium chloride were used as additives to sodium sulfate decahydrate (Glauber's salt), prioritizing environmentally responsible materials. The results reveal that CMC with molecular weights of 250 kg/mol and 90 kg/mol effectively stabilize the PCM without phase separation issues, slowing crystallization kinetics. Conversely, CMC of 700 kg/mol proved ineffective due to the disruption of gel formation at its low gel point, hindering higher concentrations. Calculations of ionic concentration indicate higher Na ion content in PCM stabilized with 90 kg/mol CMC, suggesting increased ionic interactions and gel strength. A tradeoff is discovered between the faster crystallization in lower molecular weight CMC and the higher concentration required, which increases the amount of inert material that does not participate in the phase transition. After thermal cycling, the best formulation had a latent heat of 130 J/g with no supercooling, demonstrating excellent performance. This work advances PCM's reliability as a thermal energy storage solution for diverse applications and highlights the complex relationship between Na-CMC molecular weight and PCM stabilization.

Phytochemical composition and safety of Vernonia Amygdalina ethanolic extract with anti-colon cancer properties

This study evaluates the therapeutic efficacy and safety of Vernonia Amygdalina extract (VAEE) in treating colorectal cancer (CRC) induced by azoxymethane/dextran sulfate sodium (AOM/DSS) in mice and to elucidate the underlying mechanisms. The study utilized a mouse model of CRC to assess the impact of VAEE on pathological markers, inflammatory mediators, and oxidative stress. Phytochemical profiling of VAEE was conducted using LC-HRMS, focusing on phenolic compounds. The extract's antioxidant activity was quantified, and its safety profile was verified through acute toxicity assessments. VAEE significantly mitigated the AOM/DSS-induced reduction in colon length and weight loss in a dose-dependent manner. The treatment decreased pro-inflammatory cytokines (IL-6, IL-1β, TNF-α) while increasing the anti-inflammatory cytokine IL-10. VAEE also demonstrated strong antioxidant activity and did not adversely affect blood, kidney, or liver biomarkers, confirming its non-toxicity. Protein-protein interaction analysis suggested VAEE's role in inhibiting inflammatory markers, including COX-2, IL-18, and NF-kB. Molecular docking results supported the extract's affinity for these proteins, indicating potential as a COX-2 inhibitor. VAEE exhibits potent anti-inflammatory, antioxidative, and anticarcinogenic properties against CRC, with a favorable safety profile. These findings advocate for the integration of VAEE as a novel therapeutic agent in CRC treatment. Further investigations into its molecular mechanisms and long-term effects are warranted to facilitate clinical translation.

Influence of Surfactant Types on the Anti-Corrosion Performance of Phosphate Chemical Conversion Coated Mg-8wt.%Li Alloy

In this work, the morphology, anti-corrosion performance and degradation mechanisms of two phosphate chemical conversion coatings containing the AEO (fatty alcohol polyoxyethylene ether) and AES (fatty alcohol polyoxyethylene ether sodium sulfate) on an as-cast Mg-8wt.%Li alloy were explored and compared. Although two coating layers had a petal-shaped structure and were composed of leaf-shaped particles, the coating layer of the AES-coated sample was relatively dense due to the smaller size of the formed petal-shaped structure. Based on the electrochemical data and hydrogen evolution measurements, the corrosion protectability of the coating layer on the AES-coated sample was better than that on the AEO-coated sample. The determined corrosion current densities (icorr) of the AES-coated and AEO-coated samples in the 3.5 wt.% NaCl solution were, respectively, 7.8 mA·cm−2 and 11.7 mA·cm−2, whereas the icorr value of the coated sample without a surfactant was 36.2 mA·cm−2.

Inhibitory Effects of Soluble Dietary Fiber from Foxtail Millet on Colorectal Cancer by the Restoration of Gut Microbiota.

Colorectal cancer (CRC) is a common malignant tumor that occurs in the colon. Gut microbiota is a complex ecosystem that plays an important role in the pathogenesis of CRC. Our previous studies showed that the soluble dietary fiber of foxtail millet (FMB-SDF) exhibited significant antitumor activity in vitro. The present study evaluated the anticancer potential of FMB-SDF in the azoxymethane (AOM)- and dextran sodium sulfate (DSS)-induced mouse CRC models. The results showed that FMB-SDF could significantly alleviate colon cancer symptoms in mice. Further, we found that FMB-SDF consumption significantly altered gut microbiota diversity and the overall structure and regulated the abundance of some microorganisms in CRC mice. Meanwhile, KEGG pathway enrichment showed that FMB-SDF can also alleviate the occurrence of colon cancer in mice by regulating certain cancer-related signaling pathways. In conclusion, our findings may provide a novel approach for the prevention and biotherapy of CRC.

New strategy for structure rearrangement of thin-film composite (TFC) polyamide (PA) membranes and offering potential use in both aqueous and organic solvents

The purity of sodium hexafluorophosphate (NaPF6) is crucial for the preparation of electrolytes in manufacturing. We propose a simple process in order to induce membrane structure rearrangement process (SRP) by activating thin-film composite (TFC) membranes with polyamide (PA) structure and explore their potential green recycling application in concentrating sodium-ion batteries (SIBs) electrolyte. The method utilizes a solution containing polar aprotic solvent as the soaking and activating solution to swell and disintegrate the loosely cross-linked PA layer, and a non-solvent solidification solution complete the SRP, enhancing the permeability of the PA layer while maintaining high rejection rates for divalent ions. Subsequently, during the further treatment of the membrane surface in structure rearrangement, tert-butanol (TBA) is introduced into the aqueous solution to reconstruct the surface PA layer, further improving the permeability. The optimal D8010T10 achieved a permeation flux of 24.2 L m−2 h−1·bar−1, with rejection rates for sodium sulfate (Na2SO4), magnesium chloride (MgCl2), and magnesium sulfate (MgSO4) reaching 94.7 %, 98.4 %, and 99.1 % respectively. And the mechanism of SRP with different solvent is analyzed and explained through dissipative particle dynamics (DPD) simulations. This study provides a commercially viable approach for manufacturing high-performance membranes. The D8010T10 membrane achieves more than 90 % separation efficiency for sodium hexafluorophosphate (NaPF6) dissolved in different solvents, providing a potential solution for the concentration and recovery of NaPF6 in lab-scale, verified its potential use in the organic solvent nanofiltration (OSN) and a path way for waste membrane recycling and degrading use in the industry.

SDH, a novel diarylheptane compound, alleviates dextran sulfate sodium (DSS)-induced colitis by reducing Th1/Th2/Th17 induction and regulating the gut microbiota in mice

Ulcerative colitis, a chronic inflammatory condition affecting the rectum and colon to varying degrees, is linked to a dysregulated immune response and the microbiota. Sodium (aS,9R)-3-hydroxy-16,17-dimethoxy-15-oxidotricyclo[12.3.1.12,6]nonadeca-1(18),2,4,6(19),14,16-hexene-9-yl sulfate hydrate (SDH) emerges as a novel diarylheptane compound aimed at treating inflammatory bowel diseases. However, the mechanisms by which SDH modulates these conditions remain largely unknown. In this study, we assessed SDH's impact on the clinical progression of dextran sodium sulfate (DSS)-induced ulcerative colitis. Our results demonstrated that SDH significantly mitigated the symptoms of DSS-induced colitis, reflected in reduced disease activity index scores, alleviation of weight loss, shortening of the colorectum, and reduction in spleen swelling. Notably, SDH decreased the proportion of Th1/Th2/Th17 cells and normalized inflammatory cytokine levels in the colon. Furthermore, SDH treatment modified the gut microbial composition in mice with colitis, notably decreasing Bacteroidetes and Proteobacteria populations while substantially increasing Firmicutes, Actinobacteria, and Patescibacteria. In conclusion, our findings suggest that SDH may protect the colon from DSS-induced colitis through the regulation of Th1/Th2/Th17 cells and gut microbiota, offering novel insights into SDH's therapeutic potential.

MicroRNA 429 regulates MMPs expression by modulating TIMP2 expression in colon cancer cells and inflammatory colitis.

In a previous study, we found that the expression of microRNA 429 (MIR429) was decreased in dextran sodium sulfate (DSS)-induced mouse colitis tissues. In this study, we aimed to investigate the interaction of MIR429 with TIMP metallopeptidase inhibitor 2 (TIMP2), one of its candidate target genes, in human colorectal cancer (CRC) cells and DSS-induced mouse colitis tissues. A luciferase reporter system was used to confirm the effect of MIR429 on TIMP2 expression. The expression levels of MIR429 and target genes in cells or tissues were evaluated through quantitative RT-PCR, western blotting, or immunohistochemistry. We found that the expression level of MIR429 was downregulated in human CRC tissues, and also showed that TIMP2 is a direct target gene of MIR429 in CRC cell lines. Furthermore, MIR429 regulate TIMP2-mediated matrix metallopeptidases (MMPs) expression in CRC cells. We also generated cell lines stably expressing MIR429 in CRC cell lines and showed that MIR429 regulates the expression of MMPs by mediating TIMP2 expression. In addition to human CRC tissues, we found that TIMP2 was highly expressed in mouse colitis tissues and human ulcerative colitis (UC) tissues. Our findings suggest that the expression of endogenous MIR429 was reduced in human CRC tissues and colitis, leading to upregulation of its target gene TIMP2. The upregulation of TIMP2 by decreased MIR429 expression in CRC tissues and inflamed tissues suggests that it may affect extracellular matrix (ECM) remodeling through downregulation of MMPs. Therefore, MIR429 may have therapeutic value for human CRC and colitis.

Narirutin mitigates dextrose sodium sulfate-induced colitis in mice by modulating intestinal flora

BackgroundUlcerative colitis (UC) is a prolonged inflammatory disease of the gastrointestinal tract. Current therapeutic options remain limited, underscoring the imperative to explore novel therapeutic strategies. Narirutin (NR), a flavonoid naturally present in citrus fruits, exhibits excellent anti-inflammatory effects in vitro, yet its in vivo efficacy, especially in UC, remains underexplored. ObjectiveThis work examined the effect of NR on dextrose sodium sulfate (DSS)-induced UC in mice in vivo, with a specific focus on the role of gut flora in it. MethodsThe effects of NR (10, 20, and 40 mg/kg) on DSS-induced UC in mice were investigated by monitoring changes in body weight, disease activity index (DAI) scores, colon length, and histological damage. Colonic levels of pro-inflammatory mediators, tight junction (TJ) proteins, and inflammation-related signaling pathway proteins were analyzed via enzyme-linked immunosorbent assay, western blot, and immunofluorescence. The role of gut microbiota in NR against colitis was analyzed through 16S rRNA sequencing, flora clearance assays, and fecal microbiota transplantation (FMT) assays. ResultsNR administration suppressed DSS-induced colitis as reflected in a decrease in body weight loss, DAI score, colon length shortening, and histological score. Furthermore, NR administration preserved the integrity of the DSS-induced intestinal barrier by inhibiting the reduction of TJ proteins (claudin3, occludin, and zonula occludens-1). Moreover, NR administration markedly repressed the activation of the toll-like receptor 4-mitogen-activated protein kinase/nuclear factor-κB pathway and reduced the amount of pro-inflammatory mediators in the colon. Importantly, the results of 16S rRNA sequencing showed that the intestinal flora of mice with colitis exhibited richer microbial diversity following NR administration, with elevated abundance of Lactobacillaceae (Lactobacillus) and decreased abundance of Bacteroidaceae (Bacteroides) and Shigella. In addition, the anti-colitis effect of NR almost disappeared after gut flora clearance. Further FMT assay also validated this gut flora-dependent protective mechanism of NR. ConclusionOur findings suggest that NR is a prospective natural compound for the management of UC by modulating intestinal flora.

Erlotinib suppresses tumorigenesis in a mouse model of colitis-associated cancer

Colitis-associated cancer (CAC) in inflammatory bowel diseases exhibits more aggressive behavior than sporadic colorectal cancer; however, the molecular mechanisms remain unclear. No definitive preventative agent against CAC is currently established in the clinical setting. We investigated the molecular mechanisms of CAC in the azoxymethane/dextran sulfate sodium (AOM/DSS) mouse model and assessed the antitumor efficacy of erlotinib, a small molecule inhibitor of the epidermal growth factor receptor (EGFR). Erlotinib premixed with AIN-93 G diet at 70 or 140 parts per million (ppm) inhibited tumor multiplicity significantly by 96%, with ∼60% of the treated mice exhibiting zero polyps at 12 weeks. Bulk RNA-sequencing revealed more than a thousand significant gene alterations in the colons of AOM/DSS-treated mice, with KEGG enrichment analysis highlighting 46 signaling pathways in CAC development. Erlotinib altered several signaling pathways and rescued 40 key genes dysregulated in CAC, including those involved in the Hippo and Wnt signaling. These findings suggest that the clinically-used antitumor agent erlotinib might be repurposed for suppression of CAC, and that further studies are warranted on the crosstalk between dysregulated Wnt and EGFR signaling in the corresponding patient population.

Engineered probiotics with sustained release of interleukin-2 for the treatment of inflammatory bowel disease after oral delivery

Inflammatory bowel disease (IBD) is a kind of auto-immune disease characterized by disrupted intestinal barrier and mucosal epithelium, imbalanced gut microbiome and deregulated immune responses. Therefore, the restoration of immune equilibrium and gut microbiota could potentially serve as a hopeful approach for treating IBD. Herein, the oral probiotic Escherichia coli Nissle 1917 (ECN) was genetically engineered to express secretable interleukin-2 (IL-2), a kind of immunomodulatory agent, for the treatment of IBD. In our design, probiotic itself has the ability to regulate the gut microenvironment and IL-2 at low dose could selectively promote the generation of regulatory T cells to elicit tolerogenic immune responses. To improve the bioavailability of ECN expressing IL-2 (ECN-IL2) in the gastrointestinal tract, enteric coating Eudragit L100-55 was used to coat ECN-IL2, achieving significantly enhanced accumulation of engineered probiotics in the intestine. More importantly, L100-55 coated ECN-IL2 could effectively activated Treg cells to regulate innate immune responses and gut microbiota, thereby relieve inflammation and repair the colon epithelial barrier in dextran sodium sulfate (DSS) induced IBD. Therefore, genetically and chemically modified probiotics with excellent biocompatibility and efficiency in regulating intestinal microflora and intestinal inflammation show great potential for IBD treatment in the future.

Preparation of a Consolidation Material of Organosilica-Modified Acrylate Emulsion for Earthen Sites and the Evaluation of Its Effectiveness

In this paper, a new consolidation material for earthen sites with silicone-modified acrylic emulsion was synthesized and applied to the consolidation test of soil samples of the site. The effectiveness was tested through the properties of soil samples on the changes in weight, color, permeability test, air permeability, hydrolysis resistance, water resistance, and salt resistance. The results show that the samples treated with the new material have an outstanding effect on hydrolysis resistance, water resistance, and salt resistance without the change in color and gas permeability. After being soaked in Na2SO4 and sodium chloride solution for half a month, the reinforced soil sample did not crack, and it could undergo 15 days of water resistance test and five cycles of sodium sulfate resistance.

Investigation on the anti-carbonation properties of alkali-activated slag concrete: Effect of activator types and dosages

In this paper, three alkaline activators, namely sodium hydroxide (SH), calcium oxide and sodium carbonate (COSC), calcium hydroxide and sodium sulfate (CHSS), and the influence of different alkali equivalents on the carbonation resistance of alkali-activated slag concrete (AASC) were investigated. By testing the mechanical properties at different carbonation ages of AASC with three types of activators at varying alkali equivalents (4%, 6%, and 8%), along with the changes in carbonation depth, this study aims to characterize hydration products and porosity through microstructural analysis. The objective is to explain the mechanism by which carbonation affects the AASC structure. The findings showed that the carbonation rate (i.e., the growth rate of the carbonation depth) of AASC was CHSS > COSC > SH when the exciter dosages were the same, and the carbonation rate of all samples tended to slow down as the alkali components increased. Calcite and spherulite were the calcium carbonate morphologies after SH, COSC, and CHSS carbonation according to XRD, TG/DSC, and pore structure tests; the calcium carbonate content decreased with increasing alkali equivalent after carbonation. Since the pore-increasing effect of carbonation due to the destruction of C–S–H is weaker than the filling effect produced by calcium carbonate, the total pore volume of SH, COSC, and CHSS decreased due to the activator effect after carbonation. Specifically, the calcium carbonate created by carbonation repairs pores and cracks of matrix, but its presence also reduces the calcium hydroxide concentration, leading to a decrease in the alkalinity of the pore solution, which disrupts the structure of the hydration products and loosens the matrix. The focus is on which aspect is more decisive. Interestingly, small pores however decreased, while there was an increase in larger pore sizes resulting in a change in pore size distribution. However, this negative impact on pore distribution decreased with increasing alkali dosage.

Effect of knocking out mouse Slc44a4 on colonic uptake of the microbiota-generated thiamine pyrophosphate and on colon physiology.

Humans/mammals obtain vitamin B1 from dietary and gut microbiota sources. Considerable amount of the microbiota generated vitamin exists in the form of thiamine pyrophosphate (TPP), and colonocytes are capable of absorbing TPP via a specific carrier-mediated process that involves the colonic TPP transporter (cTPPT; encoded by SLC44A4). Little is known about the relative contribution of SLC44A4 toward total colonic carrier-mediated TPP uptake, and its role in colon physiology. To address these issues, we generated an Slc44a4 knockout (KO) mouse model (by Cre-Lox recombination) and found a near complete inhibition in colonic carrier-mediated 3H-TPP uptake in the Slc44a4 KO compared to Wild-type-littermates (WT). We also observed a significant reduction in KO mice body weight and a shortening of their colon compared to WT. Using RNAseq and Ingenuity Pathway Analysis (IPA) approaches, we found that knocking out the colonic Slc44a4 to lead to changes in level of expression of many genes, including up-regulation in those associated with intestinal inflammation/colitis. Finally, we found that the Slc44a4 KO mice to be more susceptible to the effect of the colitogenic dextran sodium sulfate (DSS) compared to WT animals, a finding that lends support to the recent prediction by multiple genome-wide association studies (GWAS) that the SLC44A4 is a possible colitis susceptibility gene. In summary, results of these investigations show that the Slc44a4 is the predominant/only transporter involved in colonic uptake of TPP, that the transporter is important for colon physiology, and that its deletion increases susceptibility to inflammation.