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Cardiovascular disease (CVD) frequently occurs in patients with chronic kidney disease (CKD), particularly those undergoing dialysis. The mechanisms behind this may be related to traditional risk factors and CKD-specific factors that accelerate atherosclerosis and vascular calcification in CKD patients. The accumulation of uremic toxins is a significant factor in CKD-related systemic disorders. Basic research suggests that indoxyl sulfate (IS), a small protein-bound uremic toxin, is associated with macrophage dysfunctions, including increased oxidative stress, exacerbation of chronic inflammation, and abnormalities in lipid metabolism. Strategies to mitigate the toxicity of IS include optimizing gut microbiota, intervening against the abnormality of intracellular signal transduction, and using blood purification therapy with higher efficiency. Further research is needed to examine whether lowering protein-bound uremic toxins through intervention leads to a reduction in CVD in patients with CKD. [ABSTRACT FROM AUTHOR]

Introduction: The removal of low- and medium-molecular-weight proteins has been improved with online hemodiafiltration (OL-HDF) and hemodialysis using high-flux membranes; however, the outcomes of patients with end-stage kidney disease (ESKD) undergoing dialysis treatment are still worse than in the general population. α1-Microglobulin (α1-m), with a molecular weight of 33,000 Da, may contribute to dialysis-related disorders and mortality. However, the removal is insufficient even with current OL-HDF using the polysulfone (PS) membrane, which is common in Japan. Polymethylmethacrylate (PMMA) membranes can remove medium- to high-molecular-weight proteins by adsorption. This study aimed to assess the efficacy of removing medium- to high-molecular-weight proteins, such as α1-m and β2-microglobulin (β2-m), through post-dilution OL-HDF with PMMA (Post-PMMA). The assessment was conducted in comparison to pre-dilution OL-HDF with PS (Pre-PS), using an open-label, single-arm study. Methods: Seven patients with ESKD on Pre-PS underwent Post-PMMA with replacement volume of 30 mL/min (low flow) and 50 mL/min (high flow). Clearance and removal rates of α1-m, β2-m, small molecules, inflammatory cytokines, and albumin were measured at 60 and 240 min of treatment. Results: Clearance rates of α1-m at 60 min were −2.8 ± 5.2 mL/min with Pre-PS, −0.4 ± 2.6 mL/min with Post-PMMA (low), and 0.6 ± 3.4 mL/min with Post-PMMA (high). The removal rate of α1-m was higher in Post-PMMA than that in Pre-HDF-PS (Post-PMMA [high] 17.7 ± 5.9%, Post-PMMA [low] 15.0 ± 5.6%, and Pre-PS 4.1 ± 5.5%). Adsorption clearance of β2-m was increased with Post-PMMA. Albumin leakage in Post-PMMA was not higher than that in Pre-PS. Conclusion: The removal rate of α1-m with Post-PMMA was higher than that with Pre-PS. The PMMA membrane adsorbed β2-m, suggesting the removal effect of medium- to high-molecular-weight proteins by the adsorption method. Since Post-PMMA effectively removes α1-m without excessive albumin leakage, it will be useful for patients with ESKD, especially those with a poor nutritional status. [ABSTRACT FROM AUTHOR]

Proton tautomerizaton plays an important role in many fields of chemistry and biochemistry. A study is conducted to demonstrate that salicylideneanilines are generally thermochromic in the fluid solution of isopentane or the isopentane/methylcyclohexane mixture and that the proton tautomerization, which is the origin of the thermochromism, is controlled by the aggregation of molecules.

Abstract: OH-breaking reactions in Na(H2O) n (n ⩽8) clusters were investigated by DFT calculations. The reaction paths were determined by calculating the transition state and the intrinsic reaction coordinate. NaH is formed for n ⩽2, while larger clusters undergo H-loss. Though the total hydration energies exceed the barrier of the H-loss, the fragmentation of a single water molecule requires less energy. A protic hydrogen in a water molecule captures the excess electron, and an H atom is released, leaving an OH− in the reactions with n ⩾3. The transition state of the H-loss becomes late regarding the OH-breaking, but early with respect to deformation of the clusters with increasing n. On the basis of the Atoms-In-Molecules theory, an interesting bond path was observed between H atoms belonging to different water molecules for n =6 and 8, which is considered to support the electron-hydrogen interaction. [Copyright &y& Elsevier]

Introduction: The removal of low- and medium-molecular-weight proteins has been improved with online hemodiafiltration (OL-HDF) and hemodialysis using high-flux membranes; however, the outcomes of patients with end-stage kidney disease (ESKD) undergoing dialysis treatment are still worse than in the general population. α1-Microglobulin (α1-m), with a molecular weight of 33,000 Da, may contribute to dialysis-related disorders and mortality. However, the removal is insufficient even with current OL-HDF using the polysulfone (PS) membrane, which is common in Japan. Polymethylmethacrylate (PMMA) membranes can remove medium- to high-molecular-weight proteins by adsorption. This study aimed to assess the efficacy of removing medium- to high-molecular-weight proteins, such as α1-m and β2-microglobulin (β2-m), through post-dilution OL-HDF with PMMA (Post-PMMA). The assessment was conducted in comparison to pre-dilution OL-HDF with PS (Pre-PS), using an open-label, single-arm study., Methods: Seven patients with ESKD on Pre-PS underwent Post-PMMA with replacement volume of 30 mL/min (low flow) and 50 mL/min (high flow). Clearance and removal rates of α1-m, β2-m, small molecules, inflammatory cytokines, and albumin were measured at 60 and 240 min of treatment., Results: Clearance rates of α1-m at 60 min were -2.8 ± 5.2 mL/min with Pre-PS, -0.4 ± 2.6 mL/min with Post-PMMA (low), and 0.6 ± 3.4 mL/min with Post-PMMA (high). The removal rate of α1-m was higher in Post-PMMA than that in Pre-HDF-PS (Post-PMMA [high] 17.7 ± 5.9%, Post-PMMA [low] 15.0 ± 5.6%, and Pre-PS 4.1 ± 5.5%). Adsorption clearance of β2-m was increased with Post-PMMA. Albumin leakage in Post-PMMA was not higher than that in Pre-PS., Conclusion: The removal rate of α1-m with Post-PMMA was higher than that with Pre-PS. The PMMA membrane adsorbed β2-m, suggesting the removal effect of medium- to high-molecular-weight proteins by the adsorption method. Since Post-PMMA effectively removes α1-m without excessive albumin leakage, it will be useful for patients with ESKD, especially those with a poor nutritional status., (© 2023 S. Karger AG, Basel.)

α‑glucosidase is a key enzyme that plays a role in glucose absorption in the gastrointestinal tract, and the inhibition of its activity induces the prevention of postprandial hyperglycemia. Several α‑glucosidase inhibitors have been used as medicines for type 2 diabetes, but a similar effect is observed in natural resources, including traditional herbs and their phytochemicals. To identify the presence of the α‑glucosidase inhibitory activity in herbs, in which various functional effects have been known to occur, the present study investigated the effects of hot‑water extracts of 26 types of herbs on α‑glucosidase activity in an in vitro assay. The results indicated significant increases in the inhibition of α‑glucosidase activity in 1,000 µg/ml olive (P<0.01), white willow (P<0.01) and red rooibos hot‑water extracts. Furthermore, ≥50% inhibition of α‑glucosidase activity was determined to be significant in 1,000 µg/ml coltsfoot, green tea and bearberry hot‑water extracts. In addition, the effects of bearberry, green tea and coltsfoot hot‑water extracts on α‑glucosidase activity in vivo were evaluated according to the blood glucose levels (BGLs) in maltose and glucose load model rats. It was indicated that the administration of these three herb extracts significantly reduced the increasing BGLs after maltose loading until 0.5 h compared with the control group. However, only coltsfoot extract significantly reduced the increasing BGLs after glucose loading until 0.5 h compared with the control group. Thus, the present results may facilitate the understanding of a novel functionality in traditional herbs, which could be useful for the prevention of disease onset and progression, such as in hyperglycemia and type 2 diabetes.