Nicotinamide N-Methyl Transferase as a Predictive Marker of Tubular Fibrosis in CKD.

Purpose: Chronic kidney disease (CKD) progression is complex. There are not standardized methods for predicting the prognosis of CKD. Nicotinamide N-methyltransferase (NNMT) has been shown to be associated with renal fibrosis. This study aimed to validate NNMT as a prognostic biomarker of progressive CKD. Patients and Methods: We explored the relationship between NNMT expression and CKD-related outcome variables using the NephroseqV5 and GEO databases. Additionally, a validation set of 37 CKD patients was enrolled to measure the correlation between NNMT expression levels and CKD outcomes. Furthermore, single-cell RNA sequencing data and the Human Protein Atlas were reanalyzed to investigate the expression specificity of NNMT in the kidney. Finally, to detect the status of NNMT expression with tubular fibrosis in vivo, we constructed a unilateral ureteral obstruction (UUO) mouse treated with an NNMT inhibitor. Results: Analyzing the datasets showed that NNMT was expressed mainly in proximal tubule compartments. And patients with high NNMT expression levels had a significantly lower overall survival rate compared to those with low NNMT expression levels (P = 0.013). NNMT was independent of prognosis factors in the multivariate Cox regression model, and the AUCs for CKD progression at 1, 3, and 5 years were 0.849, 0.775, and 0.877, respectively. Pathway enrichment analysis indicated that NNMT regulates the biological processes of tubulointerstitial fibrosis (TIF). In the validation group, NNMT levels were significantly higher in the CKD group combined with interstitial fibrosis. In vivo, NNMT was a high expression in the UUO group, peaking at postoperative day 21. Treatment with an NNMT inhibitor improved renal tubular interstitial fibrosis, and expression levels of FN, α-SMA, VIM, and TGF-ß1 were decreased compared with UUO (P < 0.05). Conclusion: NNMT was expressed mainly in tubular renal compartments, and associated with CKD prognosis. It holds potential as a diagnostic biomarker for tubular fibrosis in CKD.

Associations between ATG16L1 gene polymorphism and antineutrophil cytoplasmic antibody-associated vasculitis in the Chinese Guangxi population: A case-control study.

BACKGROUND: Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is an autoimmune disease often accompanied by rapidly progressive renal failure, and the genetic background is still unknown. Our study was performed to test whether autophagy-related 16 like 1 (ATG16L1) rs4663402 and rs4663396 single nucleotide polymorphisms (SNPs) were associated with AAV in the Chinese Guangxi population. METHODS: One hundred seventy seven unrelated AAV patients and 216 healthy controls were included in this case-control study. Multiplex polymerase chain reaction combined with high-throughput sequencing was used for typing, and SNPStats and SHEsis were used for association analysis, pairwise linkage disequilibrium, and haplotype analysis. RESULTS: rs4663402 and rs4663396 were in Hardy-Weinberg equilibrium in AAV and control groups. The frequencies of rs4663402 AA, AT, and TT genotypes were 82.5%, 16.9%, and 0.6%, respectively, in patients with AAV, and 83.5%, 16.2%, and 0.5%, respectively, in controls. The frequencies of rs4663396 CC, CT, and TT genotypes were 63.8%, 33.9%, and 2.3%, respectively, in patients with AAV, and 69.2%, 26.6%, and 4.2%, respectively, in controls. Haplotype analysis revealed two SNPs in a single haplotype block (D' = 1.0). Our logistic regression adjusted for sex and age showed no association between rs4663402 and rs4663396 and the risk for AAV in genetic models (p > 0.05). However, ATG16L1 rs4663396 CC and CT + TT genotypes exhibited statistically significant differences in the incidence of arthralgia (p = 0.03). CONCLUSIONS: Our results indicated that ATG16L1 rs4663402 and rs4663396 polymorphisms were not associated with AAV in the Chinese Guangxi population. ATG16L1 rs4663396 CT + TT genotype may be associated with arthralgia.

X-ray-Induced Fragmentation of Imidazolium-Based Ionic Liquids Studied by Soft X-ray Absorption Spectroscopy.

We investigated the X-ray absorption spectroscopy (XAS) fingerprint of EMImTFSI ionic liquid (IL) and its fragmentation products created by X-ray irradiation. To accomplish this, we used an open geometry where an IL droplet is directly exposed in the vacuum chamber and an enclosed geometry where the IL is confined in a cell covered by an X-ray transparent membrane. In the open geometry, the XAS signature was stable and consistent with experimental and theoretical spectra reported in the literature. In contrast, when the IL is enclosed, its XAS evolves continuously under X-ray illumination due to the accumulation of volatile fragmentation products inside the closed cell, while they evaporate in the open geometry. The changes in the XAS from the core levels of relevant elements (C, N, S, F) together with density functional theory calculations allowed us to identify the chemical nature of the fragment products and the chemical bonds most vulnerable to rupture under soft X-ray irradiation.

X-ray Absorption Spectroscopy Characterization of a Li/S Cell.

The X-ray absorption spectroscopy technique has been applied to study different stages of the lithium/sulfur (Li/S) cell life cycle. We have investigated how speciation of S in Li/S cathodes changes upon the introduction of CTAB (cetyltrimethylammonium bromide, CH3(CH2)15N⁺(CH3)3Br-) and with charge/discharge cycling. The introduction of CTAB changes the synthesis reaction pathway dramatically due to the interaction of CTAB with the terminal S atoms of the polysulfide ions in the Na2Sx solution. For the cycled Li/S cell, the loss of electrochemically active sulfur and the accumulation of a compact blocking insulating layer of unexpected sulfur reaction products on the cathode surface during the charge/discharge processes make the capacity decay. A modified coin cell and a vacuum-compatible three-electrode electro-chemical cell have been introduced for further in-situ/in-operando studies.

Fabrication of mesoporous metal oxide coated-nanocarbon hybrid materials via a polyol-mediated self-assembly process.

After clarifying the formation mechanism of a typical metal glycolate precipitate, Ti glycolate, in a polyol-mediated synthesis using acetone as a precipitation medium, we describe a simple template-free approach based on an ethylene glycol-mediated synthesis to fabricate mesoporous metal oxide coated-nanocarbon hybrid materials including TiO2 coated-carbon nanotube (CNT), SnO2 coated-CNT, Cu2O/CuO coated-CNT and TiO2 coated-graphene sheet (GS). In the approach, metal oxide precursors, metal glycolates, were first deposited on CNTs or GSs, and subsequently transformed to the metal oxide coatings by pyrolysis or hydrolysis. By a comparison between the characterization of two TiO2-CNT hybrid materials using carboxylated CNTs and pristine CNTs without carboxyl groups, the driving force for initiating the deposition of metal glycolates on the carboxylated CNTs is confirmed to be the hydrogen bonding between the carboxyl groups and the polymer chains in metal glycolate sols. The electrochemical performances of the mesoporous TiO2 coated-carboxylated CNTs and TiO2-pristine CNT hybrid materials were investigated. The results show that the mesoporous TiO2 coated-carboxylated CNT with a uniform core-shell nanostructure exhibits substantial improvement in the rate performance in comparison with its counterpart from 0.5 C to 100 C because of its higher electronic conductivity and shorter diffusion path for the lithium ion. At the extremely high rate of 100 C, the specific capacity of TiO2 of the former reaches 85 mA h g(-1), twice as high as that of the latter.