Liquid Chromatography-mass Spectrometer Research Articles

Efficient degradation of emerging organic pollutants via activation of peroxymonosulfate over Fe-N co-doped carbon materials: Singlet oxygen and electron-transfer mechanisms

Singlet oxygen (1O2) is widely recognized as an effective reactive species for the targeted oxidation of organic contaminants. However, producing 1O2 with high selectivity and efficiency remains a significant challenge. This study describes the synthesis of a N-C-loaded Fe catalyst (Fe/NC) loaded with nitrogen-doped carbon materials. The Fe/NC catalyst efficiently produces 1O2 via the activation of peroxymonosulfate (PMS), demonstrating exceptional degradation capabilities for p-chlorophenol (4-CP). Compared to the control samples of nitrogen-doped carbon (NC) and Fe/NC-x under identical conditions, the Fe/NC/PMS produced a significantly greater degradation rate (0.794min-1) for 4-CP (50mg⋅L-1) within 14min. The content of zinc was regulated to enhance the degradation of 4-CP. The durability of the catalyst was tested with a fixed-bed flow reactor, maintaining almost 100% removal efficiency over 36h on stream. The 4-CP degradation within this system was shown to be a non-radical process predominated by 1O2 and electron transfer, as shown by electrochemical methods, quenching studies, and electron paramagnetic resonance test (EPR). Moreover, Fe/NC demonstrated exceptional resistance to pH changes (3-10), natural organics, and inorganic ions while degrading organic contaminants. The degradation process of 4-CP over the Fe/NC catalyst was examined using liquid chromatography-mass spectrometer. The results of the phytotoxicity evaluation indicated a significant decrease in their toxicity within the Fe/NC/PMS/4-CP system. The satisfactory activity, stability, and universality enabled Fe/NC to serve as a promising candidate for PMS activation. This study presents a novel approach for the selective production of 1O2, enabling targeted pollutant degradation in wastewater treatment.

Altered O-Glycans in stimulated whole saliva from patients with primary Sjögren's syndrome and non-pSS sicca.

To investigate if salivary O-linked glycans are altered in primary Sjögren's syndrome (pSS), and thus contributing to explain symptoms of oral dryness, and an impaired oral mucosal barrier function leading to changes in microbial metabolism and colonization by both pathogenic and commensal microorganisms and increased prevalence of oral diseases. O-linked oligosaccharides from stimulated whole saliva (SWS) samples from 24 patients with pSS, 38 patients with non-pSS sicca, and 23 healthy controls were analyzed using liquid chromatography mass spectrometer (LC-MS). Non-fractionated reduced and alkylated saliva was dot-blotted to PVDF-membrane and O-linked oligosaccharides were released using reductive beta-elimination. The 50 most abundant glycans were identified and their intensity compared for each sample, reflecting the relative abundance of individual monosaccharide residues. Comparison of the compositions of O-glycans in SWS samples revealed higher relative levels of sialic acid (NeuAc) and lower levels of neutral amino-monosaccharides (HexNAc) in pSS and non-pSS sicca patients than in the healthy controls. MS2 fragmentation analysis of salivary O-glycans suggests that altered sulfation, fucosylation, sialylation and distribution of core types may all contribute to the observed alteration, directly or indirectly. Additionally, the short disaccharide sialyl-Tn was most abundant in the saliva samples from patients with pSS. Our findings indicate that the salivary mucin-type O-glycan profile is altered in pSS, reflecting a dysfunction of the post-translational modification of salivary mucins leading to rheological changes of saliva, oral dryness symptoms, and impaired oral mucosal barrier function. The pathophysiological significance of the aberrant O-glycosylation needs further elucidation.

Comparative Metabolic Defense Responses of Three Tree Species to the Supplemental Feeding Behavior of Anoplophora glabripennis

Elaeagnus angustifolia L. can attract adult Asian longhorned beetle (ALB), Anoplophora glabripennis (Motschulsky), and kill their offspring by gum secretion in oviposition scars. This plant has the potential to be used as a dead-end trap tree for ALB management. However, there is a limited understanding of the attraction ability and biochemical defense response of E. angustifolia to ALB. In this study, we conducted host selection experiments with ALB and then performed physiological and biochemical assays on twigs from different tree species before and after ALB feeding. We analyzed the differential metabolites using the liquid chromatograph–mass spectrometer method. The results showed that ALB’s feeding preference was E. angustifolia > P.× xiaohei var. gansuensis > P. alba var. pyramidalis. After ALB feeding, the content of soluble sugars, soluble proteins, flavonoids, and tannins decreased significantly in all species. In three comparison groups, a total of 492 differential metabolites were identified (E. angustifolia:195, P.× xiaohei var. gansuensis:255, P. alba var. pyramidalis:244). Differential metabolites were divided into overlapping and specific metabolites for analysis. The overlapping differential metabolites 7-isojasmonic acid, zerumbone, and salicin in the twigs of three tree species showed upregulation after ALB feeding. The specific metabolites silibinin, catechin, and geniposide, in E. angustifolia, significantly increased after being damaged. Differential metabolites enriched in KEGG pathways indicated that ALB feeding activated tyrosine metabolism and the biosynthesis of phenylpropanoids in three tree species, with a particularly high enrichment of differential metabolites in the flavonoid biosynthesis pathway in E. angustifolia. This study provides the metabolic defense strategies of different tree species against ALB feeding and proposes candidate metabolites that can serve as metabolic biomarkers, potentially offering valuable insights into using E. angustifolia as a control measure against ALB.

Development of a metabolome-based respiratory infection prognostic during COVID-19 arrival.

In a new respiratory virus pandemic, optimizing allocation of scarce medical resources becomes an urgent challenge. Infection prognosis takes on particular importance when allocating scarce antiviral antibodies and drugs, which are most effective when administered before the onset of severe disease. During arrival of the COVID-19 pandemic to the United States in 2020, we conducted a prognostic biomarker discovery and validation effort based upon metabolomic profiling with a liquid-chromatography-mass spectrometer (LC-MS) type used clinically for rapid toxicology. We obtained urine specimens from 163 patients presenting for evaluation. We obtained LC-MS profiles in the initial cohort and used machine learning methods to define a simplified urine metabolomic signature associated with respiratory failure or death by 90 days. This signature was composed of three metabotypes linked to intestinal microbiome metabolism and anticonvulsant use, with a receiver-operator characteristic area under the curve (ROC AUC) of 89.4%. Blinded application of this signature to the subsequent validation cohort yielded a ROC AUC of 81.2%. A model trained on the two baseline metabotypes present before intubation exhibited similar performance in the validation cohort. This study demonstrates the plausibility and promise of rapid metabolome-based prognostic discovery and validation in the opening wave of a pandemic. The approach used here could be used to inform therapeutic and resource allocation decisions early in a future epidemic.IMPORTANCEIn a new respiratory virus pandemic, the ability to identify patients at greatest risk for severe disease is essential to direct scarce medical resources to those most likely to benefit from them. Tools to predict disease severity are best developed early in a pandemic, but laboratory-based resources to develop these may be limited by available technology and by infection precautions. Here, we show that an accessible metabolic profiling approach could identify a prognostic signature of severe disease in the initial wave of COVID-19, when patients presenting for care often exceeded the available doses of convalescent plasma and remdesivir. In a future pandemic, this approach, alongside efforts to identify clinical disease severity predictors, could improve patient outcomes and facilitate therapeutic trials by identifying individuals at high risk for severe disease.

Clinical efficacy of washed microbiota transplantation on metabolic syndrome and metabolic profile of donor outer membrane vesicles.

To clarify the clinical efficacy of washed microbiota transplantation (WMT) for metabolic syndrome (MetS), and explore the differences in the metabolic profile of bacterial outer membrane vesicles (OMVs) in donor fecal bacteria suspension received by MetS patients with good and poor outcomes, and to construct a predictive model for the efficacy of WMT for MetS using differential metabolites. Medical data 65 MetS patients who had completed at least 2 courses of WMT from 2017.05 to 2023.07 were collected. Fecal bacteria suspension of WMT donors were collected, and the clinical data of MetS patients treated with WMT during this period were collected as well. The changes of BMI, blood glucose, blood lipids, blood pressure and other indicators before and after WMT were compared. OMVs were isolated from donor fecal bacteria suspension and off-target metabolomic sequencing was performed by Liquid Chromatograph Mass Spectrometer (LC-MS). Compared with baseline, Body mass index (BMI), Systolic blood pressure (SBP) and Diastolic blood pressure (DBP) of MetS patients showed significant decreases after the 1st (short-term) and 2nd (medium-term) courses, and fasting blood glucose (FBG) also showed significant decreases after the 1st session. There was a significant difference between the Marked Response OMVs and the Moderate Response OMVs. It was showed that 960 metabolites were significantly up-regulated in Marked Response OMVs and 439 metabolites that were significantly down-regulated. The ROC model suggested that 9-carboxymethoxymethylguanine, AUC = 0.8127, 95% CI [0.6885, 0.9369], was the most potent metabolite predicting the most available metabolite for efficacy. WMT had significant short-term and medium-term clinical efficacy in MetS. There were differences in the structure of metabolites between Marked Response OMVs and Moderate Response OMVs. The level of 9-Carboxy methoxy methylguanine in Marked Response OMVs can be a good predictor of the efficacy of WMT in the treatment of MetS.

Serum metabolite profiles of thyroid autoimmunity patients in early pregnancy.

Research on serum metabolite profiles in thyroid autoimmunity (TAI) patients during early pregnancy is currently limited. The current study aimed to identify differential serum metabolites and assess the relationship between pregnancy outcomes and metabolic abnormalities in individuals with TAI. This research included 26 pregnant women with TAI and 30 healthy controls (HC). We employed a liquid chromatograph mass spectrometer (LC-MS) to analyze changes between the two groups. Newborns in the TAI patients had lower birth weights than those in the control group (P = 0.007). We identified 92 differential metabolites (including 50 upregulated and 42 downregulated) belonging to amino acids, fatty acyls, glycerophosphocholines, steroid and other categories and four significantly enrichment Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways including taurine and hypotaurine metabolism, citrate cycle (TCA cycle), glyoxylate and dicarboxylate metabolism and 2-oxocarboxylic acid metabolism. We further identified 15 characteristic metabolites (6-Methylquinoline, D-erythrose 4-phosphate, 4-Hydroxyisoleucine, phosphatidylcholine (PC)(16:2e/16:0), N3,N4-Dimethyl-L-arginine, N-desmethyltramadol, 3-Methoxybenzaldehyde, sphingomyelin (SM)(d14:3/28:2), gamma-Glutamylleucine, NSI-189, 3-(1-cyano-1,2-dihydroisoquinolin-2-yl)-3-oxopropyl propionate, lysophosphatidylinositol (LPI) 16:0, cis-Aconitic acid, polyamide (PA)(18:1/18:2) and fatty acyl esters of hydroxy fatty acid (FAHFA)(17:0/18:0)) using least absolute shrinkage and selection operator (LASSO) regression. Correlation analyses revealed that 6-Methylquinoline, D-erythrose 4-phosphate, gamma-Glutamylleucine, and LPI 16:0 exhibited a positive correlation with anemia before delivery, while 3-(1-cyano-1,2-dihydroisoquinolin-2-yl)-3-oxopropyl propionate had a negative correlation. LPI 16:0 displayed a positive correlation with uric acid (UA) during both middle and late pregnancy, whereas 3-Methoxybenzaldehyde exhibited a negative correlation with UA in late pregnancy. Cis-Aconitic acid showed a positive correlation with fasting blood glucose (FBG) in middle pregnancy. Conversely, 6-Methylquinoline and 4-Hydroxyisoleucine had a negative correlation with birth weight. Thyroid autoantibodies were found to be associated with 14 metabolites identified using LASSO, with the exception of PA (18:1/18:2). Our findings provide new evidence supporting the early screening of serum metabolites and their potential for predicting adverse pregnancy outcomes in women with TAI.

Lactobacillus johnsonii CCFM1376 improves hypercholesterolemia in mice by regulating the composition of bile acids

Aim: Strains with high bile salt hydrolase (BSH) activity have the potential to regulate cholesterol metabolism. This study aimed to assess the alleviating effect of Lactobacillus johnsonii (L. johnsonii ) CCFM1376, a strain with high BSH activity, on mice with hypercholesterolemia and explore the mechanism of its effect through the modulation of bile acid metabolism. Methods: The BSH activity was measured using the ninhydrin method. C57BL/6J mice were given a high-cholesterol diet to induce hypercholesterolemia with simultaneous gavage of L. johnsonii CCFM1376 for 8 weeks. The biochemical parameters in the serum and liver of hypercholesterolemic mice were measured to assess the alleviating effect of L. johnsonii CCFM1376 on hypercholesterolemia. Bile acid content in the mouse liver, serum, distal ileum contents, and feces was determined using liquid chromatograph mass spectrometer (LC-MS). RNA was extracted from mouse ileum and liver, and the expression levels of relative genes implicated in bile acid metabolism were measured by quantitative real-time PCR (qPCR). Results: Compared to the model group, the group treated with L. johnsonii CCFM1376 exhibited significantly reduced levels of serum total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C), along with a significant increase in high density lipoproteins cholesterol (HDL-C) level. Moreover, hepatic levels of TC and LDL-C in the CCFM1376 group also decreased significantly. Furthermore, the content and amount of unconjugated bile acids in the hepatic-enteric circulation of the L. johnsonii CCFM1376 group significantly increased, and the total bile acid content in the feces also significantly increased. In the L. johnsonii CCFM1376 group, the relative expression levels of ileal farnesoid X receptor (FXR) and fibroblast growth factor 15 (FGF15) were downregulated, while the relative expression level of CYP7A1 was upregulated. Conclusion: These results indicated L. johnsonii CCFM1376 improves hypercholesterolemia in mice by regulating the composition of bile acids. This provides a reference for probiotic strategy to regulate cholesterol metabolism.

Peroxymonosulfate activation over (Cu+ decorated g-C3N4)/Bi2WO6 composites with S-scheme heterojunction for RhB degradation

Catalytic activation of peroxymonosulfate (PMS) is one of the important research areas in the development of advanced oxidation technology for wastewater treatment. At present, the development of high-performance catalysts for PMS activation has become a research hotspot. Herein, (Cu+ decorated g-C3N4)/Bi2WO6 ((Cu+/g-C3N4)/Bi2WO6) composite was prepared successively by calcination and solvothermal method, which was used in visible light-assisted PMS activation for the degradation of rhodamine B (RhB). The construction of S-scheme heterojunctions between Cu+ decorated g-C3N4 and Bi2WO6 facilitated the activation of PMS, leading to a RhB degradation ratio of 98.46 % within 50 min. The corresponding reaction kinetic was significantly improved by a factor of 2.32 and 7.94 compared with that of CCN and BWO, respectively. The enhanced performance of the (Cu+/g-C3N4)/Bi2WO6 can be attributed to the successful construction of S-scheme heterojunction, which facilitates the separation of photogenerated carriers and accelerates the PMS activation to produce abundant active species. Furthermore, the (Cu+/g-C3N4)/Bi2WO6 composites exhibit strong stability and reusability following three cycles. In addition, the intermediates produced during the RhB degradation process were investigated by liquid chromatograph mass spectrometer (LC-MS). This study provides a new insight into the preparation of S-scheme photocatalysts for the photocatalytic-PMS activation system that will achieve efficient removal of dyes from wastewater.

Non-targeted Metabolomics-based Exploration of Radiation-induced Metabolic Alterations in Mouse Lung Epithelial Cells

Metabolic change is one of the important characteristics of radiation pneumonitis. Radiotherapy, as a conventional method for the treatment of thoracic tumors, can not only effectively kill tumor cells, but also cause adverse reactions such as local inflammation and fibrosis, which leads to limited therapeutic effect and profound impact on the quality of life of patients. Therefore, it is of great significance to explore the metabolic changes caused by radiotherapy. The aim of this study was to investigate the effects of X-ray irradiation on the metabolism of a mouse lung epithelial cell line (murine lung epithelial-12, MLE12). MLE12 cells were' cultured in vitro and randomly divided into radiation group (IR) and control group (NC). Cells in the IR group were irradiated at a dose of 10 Gy using a Hitachi X-ray irradiator. Cell supernatant samples were collected at 48 h after irradiation. Metabolomic analysis of the samples was performed by liquid chromatograph mass spectrometer (LC/MS). LC/MS metabolomics analysis revealed the metabolic changes of MLE12 cells at 48 h after irradiation. A total of 38 secretory metabolites were altered in the IR group compared with the NC group. According to the annotation of Kyoto Encyclopedia of Genes and Genomes (KEGG) database, the differential metabolites are mainly involved in nucleotide metabolism, amino acid metabolism and lipid metabolism, among which the difference in nucleotide metabolism is the most significant. The metabolism of MLE12 cells was significantly affected by X-ray irradiation, mainly affecting the nucleotide metabolic pathways, including purine and pyrimidine metabolites and related metabolic pathways.

Occurrence and profiles of bisphenol A and its analogues in marine shrimps from Tianjin and their implications for human exposure

Bisphenols, a class of compounds with endocrine-disrupting characteristics, encompassing its effects on reproduction, nervous and immune systems. Diet represents the principal route of bisphenols intake, prompting concerns about dietary exposure. In this study, the occurrence and content of nine bisphenols in 96 marine shrimps from Tianjin were detected and analysed using ultra high performance liquid chromatography mass spectrometer and solid-phase extraction. The analytical method was validated to demonstrate reliable analytical performance. The results revealed that bisphenol A was detected in the majority of the samples, with the highest detection rate among the nine bisphenols, followed by bisphenol S, while the remaining bisphenols were not detected. A discernible age-related trend was identified in the assessment of dietary exposure, whereby exposure levels increased with decreasing age. Furthermore, regional discrepancies were observed, yet no gender-based distinctions were discerned. The estimated daily intake to total bisphenols through marine shrimp in this study was lower than the current tolerable daily intake set by the European Food Safety Authority, and it can be assumed that the risk of exposure to the nine bisphenols investigated through dietary is acceptable. However, given the recently proposed draft values by the European Food Safety Authority and the higher exposures observed in children and teenagers, further surveillance and dietary guidance is required. To our knowledge, this is the first study in Tianjin to evaluate the health risks associated with bisphenol A and its analogues via marine shrimp, which can monitor dietary safety and protect population health.

Efficiency and mechanistic insights of photocatalytic degradation and sterilization utilizing g-C3N4/WO3-x Z-scheme heterojunction under full-spectrum light

Designing highly efficient full-spectrum responsive Z-scheme heterojunction for wastewater decontamination and disinfection is urgently essential. Herein, a novel Z-scheme g-C3N4/WO3-x heterojunction was successfully synthesized by a facile wet impregnation method for the highly efficient photocatalytic degradation and sterilization. Benefiting from the accelerated charge separation, broadened light absorption to near infrared region, and appropriate band energy, optimized g-C3N4/WO3-x heterojunction exhibited photocatalytic degradation of 86.3 % and 97.4 % tetracycline in 2 h under visible light and full-spectrum light, respectively. Meanwhile, 6.5-log of Escherichia coli strains could also be inactivated by optimized g-C3N4/WO3-x heterojunction within 45 min and 15 min under visible light and full-spectrum light, respectively. Impressively, it also exhibited desirable anti-interference ability and satisfying photocatalytic degradation capacity with various key experimental parameters. The plausible degradation pathways of TC and the main active species involved in the photocatalysis were investigated based on liquid chromatography-mass spectrometer (LC-MS) and electron paramagnetic resonance (EPR) analysis. Mineralization process of TC was further confirmed by three-dimensional fluorescence spectra (3D EMMs). Besides, Toxicity Estimation Software Tool (T.E.S.T.) and Ecological Structure-Activity Relationships (ECOSAR) program were applied to predict the noxiousness of TC and its potential intermediates. The results suggested that the excitotoxicity of intermediates generally decreased relative to the pristine TC. Finally, we propose a plausible enhancement mechanism of photocatalytic degradation and sterilization. This work sheds a new light on the design of novel full-spectrum responsive Z-scheme heterojunction for environmental remediation.

Comparison of different processed products of Allium tuberosum Rottler for the treatment of mice asthenozoospermia.

Allium tuberosum Rottler improves sexual function and is used in the treatment of impotence and spermatorrhea. However, its chemical composition and mechanism of action remain unclear. This study investigates the chemical composition and mechanism of action of Allium tuberosum Rottler co-processed with salt and wine (GZP) in modulating testicular mitochondrial autophagy for the treatment of asthenozoospermia in mice. Adenine gavage + cyclophosphamide intraperitoneal injection was used to establish the model of asthenozoospermia, and six Allium tuberosum Rottler processed products were compared in the pharmacological efficacy for the treatment of asthenozoospermia in mice. The liquid chromatograph mass spectrometer (LC-MS) assay was performed to analyse the compositional changes in the GZP. The mechanism of GZP in the treatment of asthenozoospermia in mice was further investigated. The mitophagy was detected by transmission electron microscope (TEM) and immunofluorescence, respectively. Reactive oxygen species (ROS) were detected by probe. Protein expression was determined by Western blotting. GZP exhibited optimal therapeutic effects on asthenozoospermia in mice. It showed the best therapeutic effect in improving the total number of spermatozoa, sperm survival rate, improving sperm viability and reducing sperm deformity rate, alleviating the abnormal pathological morphology of mice testis, and increasing the serum testosterone (T), follicle-stimulating hormone (FSH) and prolactin (PRL) levels in mice. The LC-MS detection found that Allicin showed the most significant increase in GZP. Besides, GZP reduced ROS level and inhibited mitophagy in mice testicular tissues. Meanwhile, it restrained the expression of PINK1, Parkin, Light chain 3II (LC3-II)/Light chain 3I (LC3-I) and Caspase-3 proteins. GZP improves asthenozoospermia via inhibiting excessive mitophagy and protects the integrity of mitochondria by blocking the PINK1/Parkin signaling pathway. During which, the Allicin may play an important role.

Identification of Method-Induced Artifacts and Light Chain C-terminal Extension Sequence Variants in Therapeutic Monoclonal Antibodies by Complementary Analytical Methods

Background: Atypical peaks were observed in capillary electrophoresis with sodium dodecyl sulfate (CE-SDS) during the development of therapeutic monoclonal IgG4 antibodies (mAb-X). Based on the previous literature reports, the atypical peak may be caused by various factors such as post-translational modifications (PTMs), method-induced artifacts, sample degradation and sequence variants. Due to the high complexity structure of mAbs and the limitations of CE-SDS, acquiring comprehensive profiling of atypical peaks has historically been challenging. Objective: Here we developed a strategy utilizing complementary analytical methods to identify the cause of atypical peak. Methods: This strategy includes optimizing reduced CE-SDS method to evaluate artifacts induced by the analytical method, excluding potential glycation modifications, and utilizing Liquid Chromatograph Mass Spectrometer (LC-MS) to characterize mAb-X. Results: Our study demonstrates that the atypical peaks of mAb-X are a mixture of method-induced artifacts and variants in the C-terminal extension sequence of the light chain. Conclusion: Strategy for complementary analytical methods tools helps to identify the cause of unknown species and plays a key role in product and process characterization.

TGM2-Mediated Autophagy Contributes to the Radio-Resistance of Non-Small Cell Lung Cancer Stem-like Cells.

Objectives: Cancer cells with 'stemness' are generally resistant to chemoradiotherapy. This study aims to compare the differences in radiation sensitivity of A549 and CD44+A549 stem-like cells to X-rays and carbon ion radiation (C-ions), and to find a target that can kill cancer stem-like cells (CSCs) of non-small cell lung cancer (NSCLC). Methods: The study used two cell lines (A549 and CD44+A549). The tumorigenicity of cells was tested with animal experiments. The cells were irradiated with X-rays and C-ions. Cell viability was detected using the CCK-8 and EdU assay. A liquid chromatograph-mass spectrometer (LC-MS) helped detect metabolic differences. Protein and mRNA expression were detected using a Western blot, reverse transcription-quantitative (RT-qPCR), and PCR array. The autophagic activity was monitored with a CYTO-ID® Autophagy Detection Kit 2.0. Immunofluorescence and co-immunoprecipitation helped to observe the localization and interaction relationships. Results: First, we verified the radio-resistance of CD44+A549 stem-like cells. LC-MS indicated the difference in autophagy between the two cells, followed by establishing a correlation between the radio-resistance and autophagy. Subsequently, the PCR array proved that TGM2 is significantly upregulated in CD44+A549 stem-like cells. Moreover, the TGM2 knockdown by small interfering RNA could decrease the radio-resistance of CD44+A549 cells. Bioinformatic analyses and experiments showed that TGM2 is correlated with the expression of CD44 and LC3B. Additionally, TGM2 could directly interact with LC3B. Conclusions: We established the CD44-TGM2-LC3 axis: CD44 mediates radio-resistance of CD44+A549 stem-like cells through TGM2 regulation of autophagy. Our study may provide new biomarkers and strategies to alleviate the radio-resistance of CSCs in NSCLC.

Bioactive proteins and antioxidant peptides from Litsea cubeba fruit meal: Preparation, characterization and ameliorating function on high-fat diet-induced NAFLD through regulating lipid metabolism, oxidative stress and inflammatory response

Non-alcoholic fatty liver disease (NAFLD) plays an increasingly significant threat to human health. In this study, the processing by-products of Litsea cubeba fruit meal were defatted by ultrasound-assisted methods, then the acetone-precipitated protein of L. cubeba (LCP) was obtained and structural analysis was performed. LCP was hydrolyzed by a two-step sequential hydrolysis method using alcalase and papain. Subsequently, antioxidant peptide fraction (IV2) was isolated and identified from the resultant hydrolysate through membrane ultrafiltration, Sephadex G-15 chromatography, and liquid chromatograph mass spectrometer (LC-MS). Animal experimentation indicated the potential of IV2 to mitigate hepatic steatosis. Moreover, IV2 could effectively reduce oxidative stress-induced damage by modulating the Keap1-Nrf2 pathway to activate downstream heme oxygenase-1 (HO-1) and NAD(P) H quinone oxidoreductase 1 (NQO1). Integrating metabolomics and transcriptomics revealed enrichment in pathways associated with glycerolipid metabolism and fatty acid β-oxidation, suggesting the principal mechanisms underlying IV2's ameliorative effects on NAFLD. Transcriptome sequencing identified 3092 up-regulated and 3010 down-regulated genes following IV2 treatment. Interaction analyses based on different lipid compositions (DELs) and differentially expressed genes (DEGs) indicated that IV2 primarily alleviated hepatic steatosis by modulating peroxisome proliferator-activated receptor α (PPAR-α) related pathways, thereby augmenting fatty acid β-oxidation within liver cells. These results indicate that IV2 shows potential in improving high-fat diet (HFD)-induced NAFLD, with improved fatty acid β-oxidation and reduced triglyceride biosynthesis emerging as underlying mechanisms.

Liquid Chromatography Mass Spectrometric Method and a Fluorometric 96 Well Plate Assay for Determination of Thiamine in Salmonid Eggs.

Thiamine deficiency is a large contributor to reduced reproduction success among salmonids throughout the northern hemisphere. In Scandinavia, this reproduction disorder is known as M74; while in North America, it is known as early mortality syndrome (EMS). The disorder fluctuates in magnitude from year to year. During years with high prevalence of the disorder, salmonid hatcheries that stock various aquatic systems to maintain the population size experience difficulties filling their quotas without thiamine treatment of alevins. The disorder is monitored both by observing the survival rate and by measuring the thiamine content of prefertilized eggs in the hatcheries. Here, a simple extraction procedure is presented, which allows for quantitative determination of the various phosphorylated forms of thiamine using liquid chromatography mass spectrometry but also allows for extraction in 96 deep-well plates and measurement of the total thiamine content using fluorescence monitoring with a plate reader, following oxidation of thiamine to thiochrome. The latter procedure could also be integrated into a highly portal system where the thiochrome is determined using the DeNovix QFX analyzer. The newly developed extraction procedure and cleanup method for fluorescence measurement represent the most versatile and simple methods to date for monitoring of thiamine in salmonid eggs. The methods produced accurate and precise data with quantification limits below the limit where the deficiency causes 100% lethality.

Unbalanced Expression of Structural Genes in Carotenoid Pathway Contributes to the Flower Color Formation of the Osmanthus Cultivar 'Yanzhi Hong'.

Carotenoids are important natural pigments that are responsible for the fruit and flower colors of many plants. The composition and content of carotenoid can greatly influence the color phenotype of plants. However, the regulatory mechanism underling the divergent behaviors of carotenoid accumulation, especially in flower, remains unclear. In this study, a new cultivar Osmanthus fragrans 'Yanzhi Hong' was used to study the regulation of carotenoid pigmentation in flower. Liquid chromatograph-mass spectrometer (LC-MS) analysis showed that β-carotene, phytoene, lycopene, γ-carotene, and lutein were the top five pigments enriched in the petals of 'Yanzhi Hong'. Through transcriptome analysis, we found that the expression of the structural genes in carotenoid pathway was imbalanced: most of the structural genes responsible for lycopene biosynthesis were highly expressed throughout the flower developmental stages, while those for lycopene metabolism kept at a relatively lower level. The downregulation of LYCE, especially at the late developmental stages, suppressed the conversion from lycopene to α-carotene but promoted the accumulation of β-carotene, which had great effect on the carotenoid composition of 'Yanzhi Hong'. Ethylene response factor (ERF), WRKY, basic helix-loop-helix (bHLH), v-myb avian myeloblastosis viral oncogene homolog (MYB), N-Acetylcysteine (NAC), auxin response factor (ARF), and other transcription factors (TFs) have participated in the flower color regulation of 'Yanzhi Hong', which formed co-expression networks with the structural genes and functioned in multiple links of the carotenoid pathway. The results suggested that the cyclization of lycopene is a key link in determining flower color. The modification of the related TFs will break the expression balance between the upstream and downstream genes and greatly influence the carotenoid profile in flowers, which can be further used for creating colorful plant germplasms.

BiOBr/FeMoO4 composite achieves oxygen vacancy concentration adjustment to promote persulfate activation degradation of organic pollutants in saline water

The investigation about the mechanism of crystal plane regulation on the generation of oxygen vacancies remains a challenge. In this paper, BiOBr/FeMoO4 composites were synthesized by precise control of crystal plane growth, and it exhibited the enhanced concentration of oxygen vacancies due to lower formation energy of oxygen vacancies. The composite performs higher photo-Fenton-like ability for degrading oxytetracycline hydrochloride (OTC). Structural analyses and theoretical calculations reveal that crystal plane regulation induces significant changes in oxygen vacancy concentration. The BiOBr/FeMoO4/peroxydisulphate (PDS) /light system, which dominated by the non-radical pathway, degraded 96.8 % ± 1.0 % of OTC within 30 min. The activation mechanism of the system and the degradation pathway of OTC were elucidated. The intermediates in the degradation process of OTC were evaluated using liquid chromatograph-mass spectrometer (LC-MS), toxicity evaluation software tool (T.E.S.T) and soybean germination experiments. This work offers novel insights into the pivotal role of crystal plane directional regulation in the quantitative generation of oxygen vacancies.

Enhanced visible light responsive piezoelectric photocatalysis based on Bi2S3 coated BaTiO3 nanorods heterostructures

Although the presence of the built-in electric field will solve the problem of carrier complexation in photocatalytic systems to some extent. However, free carriers will quickly shield the stabilized electric field and lose its effect. Therefore, how to introduce the dynamic piezoelectric field into the photocatalytic system has become an imminent problem. Herein, we developed an overcoated, visible light responsive, piezoelectric-assisted photocatalytic system by depositing Bi2S3 photocatalysts with a narrow-band system onto the surface of highly piezo-responsive BaTiO3 nanorods (BTO NRs). The heterojunction structure, bound by Bi-O chemical bonding, enhances carrier transport efficiency under the influence of the piezoelectric field. In the degradation experiments, the first-order rate constant for the degradation of chlortetracycline hydrochloride (CTC) in the BTO NRs/Bi2S3 system with the optimal complex ratio was 0.0276 min−1, which was 3.1 and 7.8 times higher than that of BTO NRs and Bi2S3, respectively. Additionally, we deduced the degradation pathways of CTC through a combination of Density functional theory (DFT) calculations and Liquid Chromatograph Mass Spectrometer (LC-MS), evaluating the toxicity of the intermediates. This complex system, featuring a highly photo-responsive semiconductor as a photo-acceptor deposited on a piezoelectric semiconductor surface providing a dynamic built-in electric field, enhances carrier separation efficiency under optimal light energy utilization conditions. These findings present novel and effective strategies for addressing two primary challenges in photocatalytic systems: low spectral utilization and significant photogenerated carrier complexation.

Transcriptomics and metabolomics analyses of graphene oxide toxicity on porcine alveolar macrophages

Graphene oxide (GO) is a type of nanomaterial widely used in tissue engineering, photocatalysis, and biomedicine. GO has been found to produce adverse effects on a broad range of cells and tissues. However, the molecular mechanisms underlying GO toxicity still remain to be explored. In this study, using porcine alveolar macrophages as a study model, we explored the toxic effects of GO and performed genome-wide detection of genes and metabolites associated with GO exposure using RNA-seq and liquid chromatograph mass spectrometer techniques. GO exposure significantly inhibited cell viability and induced apoptosis and oxidative stress in porcine alveolar macrophages. Further, GO exposure promoted cellular inflammation by upregulating the expression of pro-inflammatory cytokines (IL-6, IL-8, and IL-12). Transcriptomic analysis of GO-exposed cells revealed 424 differentially expressed genes. Functional enrichment analysis showed that the differentially expressed genes were significantly enriched in the pathways of Ribosome and oxidative phosphorylation (OXPHOS). In addition, metabolic analysis identified 203 differential metabolites, and these metabolites were significantly enriched in biosynthesis of cofactors, purine metabolism, and nucleotide metabolism. Integrative analyses of transcriptome and metabolome showed that OXPHOS was the most significantly enriched pathway and the involved genes were downregulated. This study revealed the toxic effects of GO on porcine alveolar macrophages and provided global insights to the metabolomic and transcriptomic alterations related to GO exposure. The results contributed to our understanding of the molecular mechanism of GO, and may further promote the detection of biomarkers for the prediction and control of GO toxicity.