Integrated Mechanism of Immune Response Modulation by Arctium Lappa L. Fructans Based on Microbiome and Metabolomics Technologies.

Arctium lappa L. is widely consumed for its various biological effects, and polysaccharides are its main functional components. The present study aimed to evaluate the immunoregulatory effects of the main polysaccharides from burdock (ALP-1) and reveal the underlying mechanisms. ALP-1 consisted of fructose and glucose (14.57:1) and had a molecular weight of 2757 Da, with typical characteristics of (1 → 2)-linked linear fructans. Oral intake of ALP-1 significantly increased the number of colonic goblet cells, serum immunoglobulin A and immunoglobulin G levels, and fecal secretory immunoglobulin A content as well as up-regulated antioxidant enzymes and increased short chain fatty acid production. In addition, ALP-1 administration regulated pro/anti-inflammatory cytokines (i.e., interleukin (IL)-1ß, IL-6, tumor necrosis factor-α, interferon-γ, and IL-10), intestinal microbiota structure, and the spatial information on key metabolites. Some gut-microbiota-mediated metabolic processes were also significantly altered. These results indicated that ALP-1 could exert beneficial effects on immune responses and intestinal health in healthy mice.

Unveiling the regulatory mechanisms of nodules development and quality formation in Panax notoginseng using multi-omics and MALDI-MSI.

INTRODUCTION: Renowned for its role in traditional Chinese medicine, Panax notoginseng exhibits healing properties including bidirectional regulatory effects on hematological system diseases. However, the presence of nodular structures near the top of the main root, known as nail heads, may impact the quality of the plant's valuable roots. OBJECTIVES: In this paper, we aim to systematically analyze nail heads to identify their potential correlation with P. notoginseng quality. Additionally, we will investigate the molecular mechanisms behind nail head development. METHODS: Morphological characteristics and anatomical features were analyzed to determine the biological properties of nail heads. Active component analysis and MALDI mass spectrometry imaging (MALDI-MSI) were performed to determine the correlation between nail heads and P. notoginseng quality. Phytohormone quantitation, MALDI-MSI, RNA-seq, and Arabidopsis transformation were conducted to elucidate the mechanisms of nail head formation. Finally, protein-nucleic acid and protein-protein interactions were investigated to construct a transcriptional regulatory network of nodule development and quality formation. RESULTS: Our analyses have revealed that nail heads originate from an undeveloped lateral root. The content of ginsenosides was found to be positively associated with the amount of nail heads. Ginsenoside Rb1 specifically accumulated in the cortex of nail heads, while IAA, tZR and JAs also showed highest accumulation in the nodule. RNA-seq analysis identified PnIAA14 and PnCYP735A1 as inhibitors of lateral root development. PnMYB31 and PnMYB78 were found to form binary complexes with PnbHLH31 to synergistically regulate the expression of PnIAA14, PnCYP735A1, PnSS, and PnFPS. CONCLUSION: Our study details the major biological properties of nodular structures in P. notoginseng and outlines their impact on the quality of the herb. It was also determined that PnMYB31- and PnMYB78-PnbHLH31 regulate phytohormones and ginsenosides accumulation, further affecting plant development and quality. This research provides insights for quality evaluation and clinical applications of P. notoginseng.

Molecularly Imprinted Heterostructure-Assisted Laser Desorption Ionization Mass Spectrometry Analysis and Imaging of Quinolones.

Quinolone residues resulting from body metabolism and waste discharge pose a significant threat to the ecological environment and to human health. Therefore, it is essential to monitor quinolone residues in the environment. Herein, an efficient and sensitive matrix-assisted laser desorption/ionization mass spectrometry (MALDI/MS) method was devised by using a novel molecularly imprinted heterojunction (MIP-TNs@GCNs) as the matrix. Molecularly imprinted titanium dioxide nanosheets (MIP-TNs) and graphene-like carbon nitrides (GCNs) were associated at the heterojunction interface, allowing for the specific, rapid, and high-throughput ionization of quinolones. The mechanism of MIP-TNs@GCNs was clarified using their adsorption properties and laser desorption/ionization capability. The prepared oxygen-vacancy-rich MIP-TNs@GCNs heterojunction exhibited higher light absorption and ionization efficiencies than TNs and GCNs. The good linearity (in the quinolone concentration range of 0.5-50 pg/µL, R2 > 0.99), low limit of detection (0.1 pg/µL), good reproducibility (n = 8, relative standard deviation [RSD] < 15%), and high salt and protein resistance for quinolones in groundwater samples were achieved using the established MIP-TNs@GCNs-MALDI/MS method. Moreover, the spatial distributions of endogenous compounds (e.g., amino acids, organic acids, and flavonoids) and xenobiotic quinolones from Rhizoma Phragmitis and Rhizoma Nelumbinis were visualized using the MIP-TNs@GCNs film as the MALDI/MS imaging matrix. Because of its superior advantages, the MIP-TNs@GCNs-MALDI/MS method is promising for the analysis and imaging of quinolones and small molecules.

How to tackle non-specific low back pain among adult patients? A systematic review with a meta-analysis to compare four interventions.

OBJECTIVE: To tackle non-specific low back pain (NSLBP) among patients and find the most effective solution and to quantitatively synthesize the overall effect of motor control training (MCT) compared with Pilates, McKenzie method, and physical therapy (PT) in pain and physical function. METHODS: Randomized controlled trials (RCTs) of four types of intervention (MCT, Pilates, McKenzie method, and PT) for LBP were collected by searching PubMed, Web of Science, EBSCOhost (Cochrane Central Register of Controlled Trials), and Scopus databases from the establishment of the database to September 30, 2023. The risk of bias was evaluated for included studies using the Revised Cochrane Risk of Bias tool for randomized trials (RoB 2.0). Taking pain and physical function in the experimental and control groups as outcome indicators, subgroup analysis was performed according to the intervention method to calculate the standardized mean difference (SMD) and 95% confidence interval (CI). RESULTS: A total of 25 RCTs, including 1253 patients, were included. Meta-analysis showed that MCT effectively relieved pain [SMD = -0.65, 95% CI (- 1.00, - 0.29), p < 0.01] and improved physical function [SMD = -0.76, 95% CI (- 1.22, - 0.31), p < 0.01] comparing with other 3 types of intervention. Subgroup analysis suggested that MCT could alleviate pain [SMD = -0.92, 95% CI (- 1.34, - 0.50), p < 0.01] and improve physical function [SMD = -1.15, 95% CI (- 1.72, - 0.57), p < 0.01] compared with PT, but it had no statistical significance compared with Pilates [pain: SMD = 0.13, 95% CI (- 0.56, 0.83), p = 0.71; physical function: SMD = 0.10, 95% CI (- 0.72, 0.91), p = 0.81] and the McKenzie method [pain: SMD = -0.03, 95% CI (- 0.75, 0.68), p = 0.93; physical function: SMD = -0.03, 95% CI (- 1.00, 0.94), p = 0.95]. CONCLUSIONS: MCT can effectively relieve pain and improve physical function in patients with NSLBP. It is more effective compared with PT for LBP, while no differences were detected between MCT and Pilates, as well as McKenzie method. Therefore, MCT, Pilates, and the McKenzie method should be encouraged as exercise interventions for NSLBP rehabilitation.

A single atom cobalt anchored MXene bifunctional platform for rapid, label-free and high-throughput biomarker analysis and tissue imaging.

Few of single-atom materials have been served as platform to analyze small molecules for surface assisted laser desorption/ionization mass spectrometry (SALDI-MS). Herein, a novel single Co atom-anchored MXene (Co-N-Ti3C2) is prepared to achieve enhanced SALDI-MS and mass spectrometry imaging (MSI) performance for the first time. The Co-N-Ti3C2 films were prepared by a simple in situ self-assembly strategy to generate an efficient SALDI-MS platform. Compared to typical inorganic/organic matrices, Co-N-Ti3C2 films exhibit superior performance in small molecules detection with ultra-high sensitivity (LOD at amol level), excellent repeatability (CV <4%), clean background and wide analyte coverage, enabling accurate quantitative analysis of various low-concentration metabolites from 1 µL biofluid in seconds. Its usage efficiently enhanced SALDI-MS detection of various small-molecule biomarkers such as amino acids, succinic acid, itaconic acid, arachidonic acid, citrulline, prostaglandin E2, creatinine, uric acid, glutamine, D-mannose, cholesterol and inositol in positive ion mode. The blood glucose level in humans was successfully determined from a linearity concentration range (0.25-10 mM). Notably, the Co-N-Ti3C2 assisted SALDI-MSI enables study the spatial distribution of small molecules covering the range central to metabolomics at a high resolution on a tissue section. Furthermore, Co-N-Ti3C2 platform revealed a specific peak profile that distinguishes osteoarthritis (OA) from rheumatoid arthritis (RA) tissue. Density functional theory theoretical investigation revealed that single Co atoms anchored on Ti3C2 could highly enhanced the ionization ability of metabolites, resulting in high-sensitivity and heterogeneous metabolome coverage.

The Prophylactic Protection of Salmonella Typhimurium Infection by Lentilactobacillus buchneri GX0328-6 in Mice.

Salmonellosis is a disease caused by non-typhoid Salmonella, and although some lactic acid bacteria strains have been shown previously to relieve Salmonellosis symptoms, little has been studied about the preventive mechanism of Lentilactobacillus buchneri (L. buchneri) against Salmonella infection in vivo. Therefore, the L. buchneri was fed to C57BL/6 mice for 10 days to build a protective system of mice to study its prevention and possible mechanisms. The results showed that L. buchneri GX0328-6 alleviated symptoms caused by Salmonella typhimurium infection among C57BL/6 mice, including low survival rate, weight loss, increase in immune organ index and hepatosplenomegaly, and modulated serum immunoglobulin levels and intrinsic immunity. Importantly, the L. buchneri GX0328-6 enhanced the mucosal barrier of the mouse jejunum by upregulating the expression of tight junction proteins such as ZO-1, occludins, and claudins-4 and improved absorptive capacity by increasing the length of mouse jejunal villus and the ratio of villus length to crypt depth and decreasing the crypt depth. L. buchneri GX0328-6 reduced the intestinal proliferation and invasion of Salmonella typhimurium by modulating the expression of antimicrobial peptides in the intestinal tract of mice, and reduced intestinal inflammation and systemic spread in mice by downregulating the expression of IL-6 and promoting the expression of IL-10. Furthermore, L. buchneri GX0328-6 increased the relative abundance of beneficial bacteria colonies and decreased the relative abundance of harmful bacteria in the cecum microflora by modulating the microflora in the cecum contents.

Mesomycoplasma ovipneumoniae from goats with respiratory infection: pathogenic characteristics, population structure, and genomic features.

BACKGROUND: Mycoplasma ovipneumoniae is a critical pathogen that causes respiratory diseases that threaten Caprini health and cause economic damage. A genome-wide study of M. ovipneumoniae will help understand the pathogenic characteristics of this microorganism. RESULTS: Toxicological pathology and whole-genome sequencing of nine M. ovipneumoniae strains isolated from goats were performed using an epidemiological survey. These strains exhibited anterior ventral lung consolidation, typical of bronchopneumonia in goats. Average nucleotide identity and phylogenetic analysis based on whole-genome sequences showed that all M. ovipneumoniae strains clustered into two clades, largely in accordance with their geographical origins. The pan-genome of the 23 M. ovipneumoniae strains contained 5,596 genes, including 385 core, 210 soft core, and 5,001 accessory genes. Among these genes, two protein-coding genes were annotated as cilium adhesion and eight as paralog surface adhesins when annotated to VFDB, and no antibiotic resistance-related genes were predicted. Additionally, 23 strains carried glucosidase-related genes (ycjT and group_1595) and glucosidase-related genes (atpD_2), indicating that M. ovipneumoniae possesses a wide range of glycoside hydrolase activities. CONCLUSIONS: The population structure and genomic features identified in this study will facilitate further investigations into the pathogenesis of M. ovipneumoniae and lay the foundation for the development of preventive and therapeutic methods.

Lactobacillus plantarum GX17 benefits growth performance and improves functions of intestinal barrier/intestinal flora among yellow-feathered broilers.

Lactobacillus plantarum has recently been found to be a natural source feed additive bacteria with great advantages in food safety and animal welfare. Discovering novel strains with commercial application potentiation could benefit the local poultry industry, and in particular support Chinese farmers. In this study, we tested a recently isolated novel strain of Lactobacillus plantarum GX17 as a feed additive on the growth performance and intestinal barrier functions of 1-day-old Chinese yellow-feather chicks. As good as other commercial probiotics, feeding with Lactobacillus plantarum GX17 showed significant improvements in humoral immune responses and enhanced the immune effect after vaccination for either the Newcastle disease vaccine or the avian influenza vaccine. This study also found that feeding with Lactobacillus plantarum GX17 improved the feed-to-weight ratio and caused a significant increase of the villus length to crypt depth ratio. Furthermore, Lactobacillus plantarum GX17 significantly up-regulated the mRNA expression of CLDN, MUC2, and TLR2, all of which are jejunum-associated barrier genes, indicating an improvement of the intestinal barrier functions by enhancing the tight junction between epithelia cells. These results are comparable to the effects of feeding the commercial complex probiotics that improve the expression levels of CLDN, ocludin, MUC2, TLR2, and TLR4. In terms of maintaining intestinal health, commercial complex probiotics increased the relative abundance of Parabacteroides and Romboutsia, while Lactobacillus plantarum GX17 increased the relative abundance of Pseudoflavonifractor. Our data suggest that Lactobacillus plantarum GX17 could enhance the intestinal absorption of nutrients and therefore improve the growth performance of Chinese yellow-feather chicks. In conclusion, compared with the commercial complex probiotics, Lactobacillus plantarum GX17 has more positive effects on the growth performance and intestinal barrier function of yellow-feather chickens, and can be used as a feed additive.

An efficient Pt@MXene platform for the analysis of small-molecule natural products.

Small-molecule (m/z<500) natural products have rich biological activity and significant application value thus need to be effectively detected. Surface-assisted laser desorption/ionization mass spectrometry (SALDI MS) has become a powerful detection tool for small-molecule analysis. However, more efficient substrates need to be developed to improve the efficiency of SALDI MS. Thus, platinum nanoparticle-decorated Ti3C2 MXene (Pt@MXene) was synthesized in this study as an ideal substrate for SALDI MS in positive ion mode and exhibited excellent performance for the high-throughput detection of small molecules. Compared with using MXene, GO, and CHCA matrix, a stronger signal peak intensity and wider molecular coverage was obtained using Pt@MXene in the detection of small-molecule natural products, with a lower background, excellent salt and protein tolerance, good repeatability, and high detection sensitivity. The Pt@MXene substrate was also successfully used to quantify target molecules in medicinal plants. The proposed method has potentially wide application.

Replication of Porcine Astrovirus Type 1-Infected PK-15 Cells In Vitro Affected by RIG-I and MDA5 Signaling Pathways.

The interferon (IFN) system is an extremely powerful antiviral response in animal cells. The subsequent effects caused by porcine astrovirus type 1 (PAstV1) IFN activation are important for the host's response to viral infections. Here, we show that this virus, which causes mild diarrhea, growth retardation, and damage of the villi of the small intestinal mucosa in piglets, induces an IFN response upon infection of PK-15 cells. Although IFN-ß mRNA was detected within infected cells, this response usually occurs during the middle stages of infection, after genome replication has taken place. Treatment of PAstV1-infected cells with the interferon regulatory factor 3 (IRF3) inhibitor BX795 decreased IFN-ß expression, whereas the nuclear factor kappa light chain enhancer of activated B cells (NF-κB) inhibitor BAY11-7082 did not. These findings indicate that PAstV induced the production of IFN-ß via IRF3-mediated rather than NF-κB-mediated signaling pathways in PK-15 cells. Moreover, PAstV1 increased the protein expression levels of retinoic acid-inducible gene I (RIG-I) and melanoma differentiation-associated protein 5 (MDA5) in PK-15 cells. The knockdown of RIG-I and MDA5 decreased the expression levels of IFN-ß and the viral loads and increased the infectivity of PAstV1. In conclusion, PAstV1 induced the production of IFN-ß via the RIG-I and MDA5 signaling pathways, and the IFN-ß produced during PAstV1 infection inhibited viral replication. These results will help provide new evidence that PAstV1-induced IFNs may protect against PAstV replication and pathogenesis. IMPORTANCE Astroviruses (AstVs) are widespread and can infect multiple species. Porcine astroviruses produce mainly gastroenteritis and neurological diseases in pigs. However, astrovirus-host interactions are less well studied, particularly with respect to their antagonism of IFN. Here, we report that PAstV1 acts via IRF3 transcription pathway activation of IFN-ß. In addition, the knockdown of RIG-I and MDA5 attenuated the production of IFN-ß induced by PAstV1 in PK-15 cells and increased efficient viral replication in vitro. We believe that these findings will help us to better understand the mechanism of how AstVs affect the host IFN response.

In Situ Self-Assembled Formation of Nitrogen-Rich Ag@Ti3C2 Film for Sensitive Detection and Spatial Imaging of Pesticides with Laser Desorption/Ionization Mass Spectrometry (LDI-MS).

Pesticide residues are hazardous to human health; thus, developing a rapid and sensitive method for pesticide detection is an urgent need. Herein, novel nitrogen-rich Ag@Ti3C2 (Ag@N-Ti3C2) was synthesized via an ecofriendly, ultraviolet-assisted strategy, followed by in situ formation of a highly homogeneous film on target carriers via a facile water evaporation-induced self-assembly process. Ag@N-Ti3C2 shows greater surface area, electrical conductivity, and thermal conductivity than Ti3C2. This Ag@N-Ti3C2 film overcomes the limitations of conventional matrixes and allows laser desorption/ionization mass spectrometry (LDI-MS) to provide fast and high-throughput analysis of pesticides (e.g., carbendazim, thiamethoxam, propoxur, dimethoate, malathion, and cypermethrin) with ultrahigh sensitivity (detection limits of 0.5-200 ng/L), enhanced reproducibility, extremely low background, and good salt tolerance. Furthermore, the levels of pesticides were quantified with a linear range of 0-4 µg/L (R2 > 0.99). This Ag@N-Ti3C2 film was used for high-throughput analysis of pesticides spiked in traditional Chinese herbs and soft drink samples. Meanwhile, high-resolution Ag@N-Ti3C2 film-assisted LDI-MS imaging (LDI MSI) was used to successfully explore spatial distributions of xenobiotic pesticides and other endogenous small molecules (e.g., amino acids, saccharides, hormones, and saponin) in the roots of plants. This study presents the new Ag@N-Ti3C2 self-assembled film equably deposits on the ITO slides and provides a dual platform for pesticide monitoring and has the advantages of high conductivity, accuracy, simplicity, rapid analysis, minimal sample volume requirement, and an imaging function.

Single-atom catalysts with peroxidase-like activity boost gel-sol transition-based biosensing.

Gel-sol transition-based biosensors are a promising and popular alternative for portable, cost-effective, and user-friendly point-of-care testing (POCT). However, the improvement of sensitivity and practicability is highly demanded. In this work, a Fe-NC single-atom catalyst (SAC) is successfully synthesized and used as a signal amplification element for highly sensitive gel-sol transition-based biosensing. The Fe-NC SAC owns excellent peroxidase-like activity of 188 U/mg due to its definite atomically active centers and maximum atomic utilization of active metal atoms. As a proof-of-concept, the Fe-NC SAC is uniformly encapsulated in gelatin hydrogel to obtain a hydrogel sensor that allows colorimetric detection of trypsin based on gel-sol transition. The gelatin hydrogel network collapses derived from the hydrolysis by trypsin, and thereby the released Fe-NC SAC leads to the colorimetric sensing process. The designed hydrogel sensor offers a low detection limit of 1 ng/mL with a range from 1 to 100 ng/mL toward trypsin detection, exhibiting excellent selectivity and sensitivity, and well-performed practical detection in human serum. This work offers a successful paradigm for designing a promising SACs-related detection strategy and paves a new way to develop high-performance gel-sol transition-based sensors and various POCT applications.

SULFORAPHANE ADMINISTRATION AFTER HEMORRHAGIC SHOCK/RESUSCITATION IN MICE REDUCES THE SECRETION OF INFLAMMATORY CYTOKINES AND INCREASES THE IMMUNOCOMPETENCE OF SPLENIC MACROPHAGES.

ABSTRACT: Objective : The purpose of this study was to investigate the immunomodulatory effects of sulforaphane (SFN), a nuclear factor erythroid 2-related factor (Nrf2) pathway activator, on splenic macrophages' immunocompetence after hemorrhagic shock/resuscitation (HS/R). Methods : Male C57/BL6 wild-type mice (n = 6 per group) were subjected to either pressure-controlled HS (MAP, 35-45 mm Hg) or a sham procedure surgery (without HS). After 90 minutes of HS, fluid resuscitation with withdrawn blood and 0.9% NaCl was performed. Sulforaphane (50 mg/kg of body weight) was applied intraperitoneally immediately after the resuscitation phase as well as 24 and 48 h thereafter, depending on group allocation. The mice were killed at 6, 24, and 72 h after resuscitation. After killing, spleens were harvested to perform Nrf2 immunofluorescence histology. Splenic macrophages were isolated and cultured to measure cytokine secretion in the cell culture supernatant. Furthermore, macrophages isolated after 24-hour resuscitation were treated with 100 ng/mL of bacterial LPS to measure immunocompetence. Matrix-assisted laser desorption/ionization mass spectrometry imaging was performed to verify the distribution of SFN in the spleen after intraperitoneal injection. Results : We showed that administered SFN reached the spleen within the first hour after administration. Furthermore, we identified that SFN increased splenic Nrf2 activation and decreased cytokine expression in splenic macrophages after HS/R. In addition, we showed that SFN exhibited splenic anti-inflammatory properties of macrophages in vitro (IL-6/IL-10-ratio of the HS/R group: 51.79 ± 9.99 [at 6 h] and 15.70 ± 3.35 [at 24 h] vs. HS/R + SFN group: 20.54 ± 5.35 [at 6 h] and 8.60 ± 2.37 [at 24 h], P < 0.05). Furthermore, SFN improved in vitro splenic macrophage immunocompetence after HS/R, as evidenced by the increased secretion of inflammatory cytokines in response to LPS stimulation in vitro . Conclusions : Our study shows that SFN can reduce inflammatory cytokines secreted by splenic macrophages after HS/R and increase their immunocompetence toward a more anti-inflammatory profile.

Immunological pathogenesis of Bovine E. coli infection in a model of C. elegans.

BACKGROUND: Cattle industry is critical for China's livestock industry, whereas E. coli infection and relevant diseases could lead huge economic loss. Traditional mammalian models would be costly, time consuming and complicated to study pathological changes of bovine E. coli. There is an urgent need for a simple but efficient animal model to quantitatively evaluate the pathological changes of bovine-derived E. coli in vivo. Caenorhabditis elegans (C. elegans) has a broad host range of diverse E. coli strains with advantages, including a short life cycle, a simple structure, a transparent body which is easily visualized, a well-studied genetic map, an intrinsic immune system which is conservable with more complicated mammalians. RESULTS: Here, we considered that O126 was the dominant serotype, and a total of 19 virulence factors were identified from 41 common E. coli virulence factors. Different E. coli strains with diverse pathogenicity strengths were tested in C. elegans in E. coli with higher pathogenicity (EC3/10), Nsy-1, Sek-1 and Pmk-1 of the p38 MAPK signaling pathway cascade and the expression of the antimicrobial peptides Abf-3 and Clec-60 were significantly up-regulated comparing with other groups. E. coli with lower pathogenicity (EC5/13) only activated the expression of Nsy-1 and Sek-1 genes in the p38 MAPK signaling pathway, Additionally, both groups of E. coli strains caused significant upregulation of the antimicrobial peptide Spp-1. CONCLUSION: Thirteen E. coli strains showed diverse pathogenicity in nematodes and the detection rate of virulence factors did not corresponding to the virulence in nematodes, indicating complex pathogenicity mechanisms. We approved that C. elegans is a fast and convenient detection model for pathogenic bacteria virulence examinations.

Ti3C2(OH)x-assisted LDI-TOF-MS for the rapid analysis of natural small molecules.

The inhomogeneous distribution of co-crystallized analytes and the traditional organic matrices as well as the intensive background interference in the low molecular weight range hinder the application of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) in the analysis of small-molecular compounds. New two-dimensional material MXene (e.g., Ti3C2) exerts better hydrophilicity, homogeneity and repeatability, and higher laser desorption efficiency, as well as less background interference than traditional organic matrices and other nanomaterial matrices such as titanium oxide, graphene, and gold nanostructures. This study was aimed to design Ti3C2 matrix with abundant hydroxyls on its surface, enhance the stability of this hydroxyl-rich Ti3C2 (Ti3C2(OH)x), and evaluate the analytical performances of Ti3C2(OH)x-assisted laser desorption/ionization time-of-flight mass spectrometry (LDI-TOF-MS) for small-molecular natural compounds in complex samples. The developed Ti3C2(OH)x showed the distinct advantages such as minimum background interference, high peak intensity (~105), high salt (0.6 M) and protein (0.5 mg/mL) tolerance, good repeatability (relative standard deviation<20%), and good stability after eight months of storage. Ti3C2(OH)x-assisted LDI-TOF-MS analysis could be used to rapidly identify Artemisia annua (a world-famous traditional Chinese medicine) and quantify the contents of the main chemical ingredients (oxymatrine (OXY) and matrine) of Compound Kushen Injection (CKI). Interestingly, the content of OXY in CKI could be accurately quantified by Ti3C2(OH)x-assisted LDI-TOF-MS, and there was a good linear relationship (R2 -0.9929), a low limit of detection (400 pg), and a low limit of quantification (600 pg) of OXY. Taken together, the rapid and accurate analysis of small-molecular natural compounds in complicated samples could be achieved by the Ti3C2(OH)x-assisted LDI-TOF-MS analysis.

[Value of serum amyloid protein dynamic changes on evaluating condition and prognosis of patients with viral and mycoplasma community-acquired pneumonia].

OBJECTIVE: To investigate the predictive role of dynamic changes of plasma biomarkers in patients with viral and mycoplasma community-acquired pneumonia (CAP). METHODS: From January 2020 to June 2020, 141 patients with viral and mycoplasma CAP in People's Hospital of Ningxia Hui Autonomous Region were enrolled. Pneumonia severity index (PSI) scores [grade I-II (PSI score ≤ 70), grade III (PSI score 71-90) and grade IV-V (PSI score ≥ 91)], serum amyloid A (SAA), hypersensitive C-reactive protein (hs-CRP), procalcitonin (PCT), erythrocyte sedimentation rate (ESR) and white blood cell (WBC) on the 1 day after admission were compared between the different pathogens (viral and mycoplasma) or different disease severity. The change in level of SAA, hs-CRP on the third day (Δ3 d = 1 d-3 d) were compared among different disease outcome groups (patients were divided into improved group, stable group and exacerbation group based on PSI scores or lung CT images on the third day). The change in the level of SAA, hs-CRP on the seventh day (Δ7 d = 1 d-7 d) were compared among different disease prognosis groups (patients were divided into survival group and death group based on 28-day survival data). The receiver operating characteristic curve (ROC) were drawn to evaluate the value of SAA in the evaluation of disease and prediction prognosis. RESULTS: The level of SAA in mycoplasma group (43 cases) was significantly higher than that in virus group (98 cases) on the 1 day after admission. There were no significant differences in other plasma biomarkers between the two groups. The more severe the illness, the higher the SAA level on the 1 day after admission. The trends of other plasma biomarkers in the two groups were consistent with SAA. The levels of SAA in the patients with exacerbation of the virus group and mycoplasma group (12 cases, 9 cases) were significantly higher than those of the improved group (57 cases, 26 cases) and the stable group (29 cases, 8 cases). SAA increased gradually in the exacerbation group, decreased gradually in the improved group, and slightly increased in the stable group. ΔSAA3 d were differences among three groups. The change trend of hs-CPR was consistent with SAA. The level of SAA in the death group was higher than that in the survival group on the seventh day. SAA increased in the death group and decreased in survival group with time from hospital admission. There were differences according to ΔSAA7 d between death group and survival group. The change trend of hs-CPR was consistent with SAA. ROC curve showed that the value of SAA was better than hs-CRP in assessing the severity of patients on admission day, and the area under ROC curve (AUC) was respectively 0.777 [95% confidence interval (95%CI) was 0.669-0.886], 0.729 (95%CI was 0.628-0.830). The value of ΔSAA3 d was better than SAA on the third day predicting disease trends, and AUC was respectively 0.979 (95%CI was 0.921-1.000), 0.850 (95%CI was 0.660-1.000). hs-CRP on the third day and Δhs-CRP3 d had no predictive value. Both SAA on the seventh day and ΔSAA7 d have predictive value for prognosis. AUC was respectively 0.954 (95%CI was 0.898-0.993) and 0.890 (95%CI was 0.689-1.000). SAA on the seventh day and ΔSAA7 d were better than hs-CRP on the seventh day. Δhs-CRP7 d have no predictive value. CONCLUSIONS: SAA is a sensitive and valuable indicator for CAP patients with viruses and mycoplasma. Dynamic monitoring of SAA can evaluate the patient's progression, prognosis, and assist diagnosis and treatment.

Surface-anchored liquid crystal droplets for the semi-quantitative detection of Aflatoxin B1 in food samples.

Aflatoxin B1 (AFB1) is a common food mycotoxin that can cause various diseases. Therefore, reliable detection methods are required to ensure food safety against mycotoxins. In this study, we design a liquid-crystal (LC)-based assay for rapid detection of AFB1 in food samples. The surface-anchored LC droplets on glass (5CBSADrop) are obtained via a solvent evaporation method. The 5CBSADrop displays a four-leaf clover appearance that corresponds to an escape-radial configuration in a mixture of CTAB and AFB1 aptamer. Interestingly, they adopt a radial configuration in the mixture of CTAB, AFB1, and its aptamer. Using this approach, AFB1 can be detected using only 1 µL of the aqueous solution with a minimum detection concentration of 10 pg/mL. This LC-based sensing platform provides simple operation, remarkable sensitivity, high selectivity, low cost, and excellent portability without the use of any bulky instrument, which is very promising in rapid on-field detection of mycotoxins.

[Spatial distribution characteristics of metabolities in rhizome of Paris polyphylla var. yunnanensis: based on MALDI-MSI].

In this study, a method was established for in-situ visualization of metabolite distribution in the rhizome of Paris polyphylla var. yunnanensis. To be specific, through matrix-assisted laser desorption/ionization-mass spectrometry imaging(MALDI-MSI), the spatial locations of steroidal saponins, amino acids, organic acids, phytosterols, phytoecdysones, nucleosides, and esters in rhizome of the medicinal plant were directly analyzed, and six unknown compounds with differential distribution in rhizome tissues were identified. The specific procedure is as follows: preparation of rhizome tissue section, matrix screening and optimization, and MALDI-MSI analysis. The results showed that the steroidal saponins were mainly distributed in the central, amino acids in epidermis and cortex, low-molecular-weight organic acids in central epidermis, phytosterols in the epidermis and lateral cortex, the phytoecdysones in epidermis and cortex, nucleosides(uneven distribution) in epidermis and cortex, growth hormones around the epidermis and cortex, particularly outside the cortex, and esters in cortex with unobvious difference among different tissues. In this study, the spatial distribution of meta-bolites in the rhizome of P. polyphylla var. yunnanensis was characterized for the first time. The result can serve as a reference for identifying and extracting endogenous metabolites of P. polyphylla var. yunnanensis, exploring the synthesis and metabolism mechanisms of the metabolites, and evaluating the quality of medicinal materials.

High-throughput screening and spatial profiling of low-mass pesticides using a novel Ti3C2 MXene nanowire (TMN) as MALDI MS matrix.

Pesticides play critical roles in agricultural fields; however, pesticide residues can cause serious damage to human health and the ecological environment; therefore, developing a rapid and sensitive method for pesticide detection is urgently needed. Nanostructure-assisted matrix laser desorption/ionization (MALDI) mass spectrometry (MS) has great potential for the detection of low-mass pesticides. In this study, a novel Ti3C2 MXene nanowire (TMN) was prepared by a facile sol-gel method and served as a matrix to enhance MALDI MS performance in the analysis of pesticides in positive ion mode. The TMN showed superior performance in the high-throughput detection of six kinds of pesticides (organophosphorus, organochlorine, carbamate, neonicotinoids, triazole, and oxadiazines), with ultrahigh sensitivity (detection limits at sub-ppt levels), remarkable repeatability, excellent salt tolerance, and extremely low background compared to traditional organic matrices due to the specific polyaromatic structure and the doping of nitrogen. Furthermore, this matrix was successfully employed for the analysis of residual pesticides in traditional Chinese herbs, and the level of diniconazole was quantified with a linear range of 0-50 ng/mL (R2 > 0.99). More importantly, the spatial distribution of various endogenous compounds (e.g., amino acids and saccharides, fatty acids, alkaloids, and plant hormones) and xenobiotic pesticides from the intact root of the medicinal plant P. quinquefolium was clearly visualized using the TMN self-assembly film as a matrix for MALDI imaging mass spectrometry (IMS). With superior advantages such as sensitivity, simplicity, rapidness, and minimal sample requirement, TMN as a matrix-assisted MALDI MS shows great promise for various applications.

AuNPs/NiFe-LDHs-assisted laser desorption/ionization mass spectrometry for efficient analysis of metronidazole and its metabolites in water samples.

Gold nanoparticles (AuNPs) have been widely used as laser desorption/ionization mass spectrometry (LDI-MS) nanomaterials for the analysis of low-molecular-weight samples. Nickel/iron-layered double hydroxides (NiFe-LDHs) nanosheets can support the anchoring of AuNPs and enhance the ability of desorption/ionization. Their hybrid nanocomposites are expected to produce synergistic effects to improve the performance of LDI-MS. In this work, a novel AuNPs/NiFe-LDHs nanomaterial was synthesized by self-assembly method and characterized based on TEM, SEM, XPS, UV-vis and FTIR-ATR. AuNPs/NiFe-LDHs assisted LDI-TOF MS exhibited higher peak intensity and lower background noise compared with conventional organic matrices. Furthermore, excellent salt and protein tolerance, good repeatability and quantification were observed when MNZ and its metabolites were detected in the range of 1-50 ng·µL-1 (R2 > 0.98), with LODs and LOQs of 0.5 ng·µL-1 and 1 ng·µL-1, respectively. This nanocomposite could also be used for the analysis of some other small molecules, such as antibiotics, sugars, amino acids and pesticides, demonstrating the potential to detect a variety of environmental chemicals. Taken together, the developed method combined the advantages of two nanomaterials and can provide rapid and accurate analysis of MNZ and its metabolites in water samples, as well as some other small molecules.