Secreted phosphoprotein 1 exacerbates renal ischemia-reperfusion injury by inhibiting PI3K/AKT signaling pathway.

BACKGROUND: Renal ischemia-reperfusion injury (IRI) is a prevalent reason for acute kidney injury and a key clinical issue for patients under anesthesia and about to have surgery. We aim to investigate the Secreted phosphoprotein 1 (SPP1) role in renal IRI and the underlying mechanisms. METHODS: Using Gene Expression Omnibus (GEO) database helped in analyzing the SPP1 expression in renal IRI. We established two models, a mouse renal ischemia-reperfusion (I/R) besides a hypoxia-reoxygenation (H/R) HK-2 cell. Renal tubular lesions were measured using H&E staining. Depending on the TUNEL assay, immunohistochemistry, qRT-PCR, as well as western blot, we applied the assessment of apoptosis and apoptosis-associated protein levels. At the same time, a western blot was performed for assessing PI3K/AKT pathway-associated proteins. RESULTS: GEO data and experimental validation revealed elevated SPP1 content in the kidney tissues of renal I/R mice more than in sham mice. In vitro and in vivo studies revealed an increase in cell apoptosis due to SPP1 overexpression, but the opposite is true when SPP1 is silenced. SPP1 downregulation led to high p-PI3K and p-AKT protein levels, and the LY294002 application inhibited SPP1 inhibition-mediated anti-apoptotic effect CONCLUSION: Taken together, SPP1 exacerbates renal IRI in vivo and in vitro via promoting programmed cell death by inhibiting PI3K/AKT signaling pathway.

Association between CD24 Ala/Val polymorphism and multiple sclerosis risk: A meta analysis.

BACKGROUND: The aim of this study was to explore the association between CD24 Ala/Val polymorphism and susceptibility of multiple sclerosis (MS). METHODS: A comprehensive literature search for relevant studies was performed on google scholar, PubMed, Web of science, Embase, the Chinese National Knowledge Infrastructure and the Chinese Biology Medicine. This meta-analysis was conducted using the STATA 11.0 software and the pooled odds ratio with 95% confidence interval was calculated. RESULTS: Seven case-control studies were included in this meta-analysis. The results showed significant association between CD24 Ala/Val polymorphism and susceptibility to MS. Stratified analysis by areas also showed significant association in Asians. However, no association was found in Europeans. CONCLUSION: This study suggested that the CD24 Val allele was associated with an increased risk of MS and larger-scale studies of populations are needed to explore the role of CD24 Ala/Val polymorphism during the pathogenesis of MS.

The preparation of a modified PVDF hollow fiber membrane by coating with multiwalled carbon nanotubes for high antifouling performance.

In this study, an outer surface modified polyvinylidene fluoride (PVDF) hollow fiber membrane (HF-PVDF-CNT) was prepared by coating with dopamine (PD) and multiwalled carbon nanotubes (CNTs), to solve the problems of the instability of pure CNT mats fabricated by filter coating methods and membrane fouling in wastewater treatment. The modified membrane was assessed and characterized by various methods, including studies of its top surface and cross-sectional morphology, wettability, functional groups and electrical conductivity. The CNT material stability was evaluated during backwashing. The antifouling and filtering abilities of the unmodified and modified membranes were tested by monitoring the change in TMP and the rejection performance for different contaminants during filtration in bovine serum albumin solution (BSA), sodium alginate solution (SA) and humic acid solution (HA). Furthermore, HF-PVDF-CNT and electro-assisted HF-PVDF-CNT membranes were employed as the basic separation units in an anaerobic membrane bioreactor (AnMBR) system and an anaerobic electrochemical membrane bioreactor (AnEMBR) system, respectively. Characterization of the HF-PVDF-CNT membrane indicated that the CNT mats exhibited good stability, electrical conductivity and wettability. In filtration experiments using BSA, SA and HA solutions, the HF-PVDF-CNT membrane showed an obvious improvement compared with the HF-PVDF membrane in antifouling performance. During its application in the AnMBR and AnEMBR systems, the electro-assisted HF-PVDF-CNT membrane had greater effects than the HF-PVDF-CNT membrane on reducing fouling.

[Nitrogen Removal Characteristics and Analysis of Microbial Community Structure in an IEM-UF Simultaneous Separation and Denitrification System].

A system that combines an ion exchange membrane and ultrafiltration membrane (IEM-UF) to form a simultaneous separation and denitrification system was proposed for domestic sewage with a low carbon/nitrogen ratio. The removal of nitrogen and COD in the system was studied under a three phase operating condition. The characteristics of the microbial community in each reactor were analyzed using metagenomics. The results show that, the average rate of ammonia nitrogen enrichment in the separator reached above 116.1% when the current intensity was 0.2 A. When the system was at C/N 2.80 and operating well, the average removal rates of COD and TN reached above 90% and 50%, respectively. The maximum removal rate of TN was above 65.4%. The results of metagenomics showed a genus of phylum Nitrospirae (Nitrospira) and a genus of phylum Proteobacteria (Nitrosomonas), with the proportions of 12.23% and 2.31%, respectively. In the denitrifying reactor, Dechloromonas, Thauera, and Azospira were detected in the proportions 4.57%, 1.76%, and 1.03%, respectively. These proportions were far larger than those of other bacteria in this reactor. Meanwhile, the presence of iron autotrophic denitrifying bacteria increased the denitrification efficiency of the system.

[Analysis of Low C/N Wastewater Treatment and Structure by the CEM-UF Combined Membrane-Nitrification/Denitrification System].

In this study, a CEM-UF composite membrane with ammonia nitrogen enrichment and separation characteristics was combined with nitrification/denitrification to treat low C/N wastewater. The denitrification characteristics of low C/N wastewater at different flow ratios were investigated, and the structural characteristics of functional microbial communities in nitrifying and denitrifying activated sludge were analyzed by 16Sr DNA high-throughput sequencing. The results showed that influent TN was 60 mg·L-1, COD/TN was 2.65, the nitrification effect of each flow rate was good, and the average ammonia nitrogen removal rate was 98.7%. When the flow ratio increased from 1:2 to 1:6, the m(COD)/m(NO3--N) of denitrification was increased, and the removal of average nitrate nitrogen reached its highest level at 1:6, which was 86.28%, and the removal of total nitrogen increased from 22.56% to 46.8%. An analysis of Illumina sequencing showed that nitrogen fixing bacteria Proteobacteria accounted for 30.9%, and the important nitrite oxidizing bacteria, Nitrospirae, accounted for 3.06%. At the genus level, Nitrosomonas and Nitrosospira, belonging to the ammonia oxidizing bacteria (AOB) category and Nitrospira and Nitrobacter, belonging to the nitrite oxidizing bacteria (NOB) category were detected. The ratio of AOB and NOB bacteria was high, which is consistent with good nitrification in the nitrification reactor. The dominant bacteria in denitrification sludge were Proteobacteria (53.13%), followed by Bacteroidetes (10.93%). A variety of bacteria related to denitrification were detected at the genus level, such as Dechloromonas, Thauera, Castellaniella, Alicycliphilus, Azospira, Comamonas, Caldilinea, and Saccharibacteria. The proportion of denitrifying bacteria was 25.91% as denitrifying bacteria microbial species were rich in the denitrifying sludge, giving a good denitrification effect.