The novel molecular mechanism of pulmonary fibrosis: insight into lipid metabolism from reanalysis of single-cell RNA-seq databases.

Pulmonary fibrosis (PF) is a severe pulmonary disease with limited available therapeutic choices. Recent evidence increasingly points to abnormal lipid metabolism as a critical factor in PF pathogenesis. Our latest research identifies the dysregulation of low-density lipoprotein (LDL) is a new risk factor for PF, contributing to alveolar epithelial and endothelial cell damage, and fibroblast activation. In this study, we first integrative summarize the published literature about lipid metabolite changes found in PF, including phospholipids, glycolipids, steroids, fatty acids, triglycerides, and lipoproteins. We then reanalyze two single-cell RNA-sequencing (scRNA-seq) datasets of PF, and the corresponding lipid metabolomic genes responsible for these lipids' biosynthesis, catabolism, transport, and modification processes are uncovered. Intriguingly, we found that macrophage is the most active cell type in lipid metabolism, with almost all lipid metabolic genes being altered in macrophages of PF. In type 2 alveolar epithelial cells, lipid metabolic differentially expressed genes (DEGs) are primarily associated with the cytidine diphosphate diacylglycerol pathway, cholesterol metabolism, and triglyceride synthesis. Endothelial cells are partly responsible for sphingomyelin, phosphatidylcholine, and phosphatidylethanolamines reprogramming as their metabolic genes are dysregulated in PF. Fibroblasts may contribute to abnormal cholesterol, phosphatidylcholine, and phosphatidylethanolamine metabolism in PF. Therefore, the reprogrammed lipid profiles in PF may be attributed to the aberrant expression of lipid metabolic genes in different cell types. Taken together, these insights underscore the potential of targeting lipid metabolism in developing innovative therapeutic strategies, potentially leading to extended overall survival in individuals affected by PF.

The Efficacy of Rule of Law Publicity Short Video Platforms in the Prevention of Medical Disputes Among Healthcare Professionals: A Propensity Score Analysis.

Background: Medical disputes are a recurrent and pressing issue in hospitals, posing significant challenges to the functioning of medical institutions. We aimed to investigate whether receiving rule of law publicity on short video platforms is relevant to preventing medical disputes among healthcare professionals. Methods: We collected the data from 37,978 medical professionals from 130 tertiary public hospitals. Participants were classified into two groups according to the presence of receiving rule of law publicity on short video platforms. A subgroup analysis was performed before and after propensity score analysis, and multiple logistic regression was used to identify risk factors for medical disputes. Results: Among all participants, 46.1% (17,506/37,978) experienced medical disputes. Before propensity score analysis, the prevalence of medical disputes among participants who received rule of law publicity on short video platforms was similar to that among participants who did not (P = 0.639). However, after propensity score analysis, participants who received the rule of law publicity on short video platforms did not show a benefit effect. These participants had a significantly higher rate of suffering from medical disputes than participants who did not receive publicity on this platform (P=0.020). Multiple logistic regression analysis confirmed that receiving the rule of law publicity through short video platforms (P=0.010) or MicroBlog (P = 0.016), and previously facing legal issues outside of medical work (P < 0.001) were risk factors for medical disputes; participating in legal training organized by hospitals (P=0.004) and the hospital rule of law being very good (P=0.045) were protective factors. Conclusion: Medical disputes are a common occurrence within the healthcare profession. However, using short video platforms to promote the rule of law is not an effective method to prevent disputes. Instead, healthcare professionals can benefit from participating in legal training and having a well-established rule of law within the hospital construct.

Prediction of Medical Disputes Between Health Care Workers and Patients in Terms of Hospital Legal Construction Using Machine Learning Techniques: Externally Validated Cross-Sectional Study.

BACKGROUND: Medical disputes are a global public health issue that is receiving increasing attention. However, studies investigating the relationship between hospital legal construction and medical disputes are scarce. The development of a multicenter model incorporating machine learning (ML) techniques for the individualized prediction of medical disputes would be beneficial for medical workers. OBJECTIVE: This study aimed to identify predictors related to medical disputes from the perspective of hospital legal construction and the use of ML techniques to build models for predicting the risk of medical disputes. METHODS: This study enrolled 38,053 medical workers from 130 tertiary hospitals in Hunan province, China. The participants were randomly divided into a training cohort (34,286/38,053, 90.1%) and an internal validation cohort (3767/38,053, 9.9%). Medical workers from 87 tertiary hospitals in Beijing were included in an external validation cohort (26,285/26,285, 100%). This study used logistic regression and 5 ML techniques: decision tree, random forest, support vector machine, gradient boosting decision tree (GBDT), and deep neural network. In total, 12 metrics, including discrimination and calibration, were used for performance evaluation. A scoring system was developed to select the optimal model. Shapley additive explanations was used to generate the importance coefficients for characteristics. To promote the clinical practice of our proposed optimal model, reclassification of patients was performed, and a web-based app for medical dispute prediction was created, which can be easily accessed by the public. RESULTS: Medical disputes occurred among 46.06% (17,527/38,053) of the medical workers in Hunan province, China. Among the 26 clinical characteristics, multivariate analysis demonstrated that 18 characteristics were significantly associated with medical disputes, and these characteristics were used for ML model development. Among the ML techniques, GBDT was identified as the optimal model, demonstrating the lowest Brier score (0.205), highest area under the receiver operating characteristic curve (0.738, 95% CI 0.722-0.754), and the largest discrimination slope (0.172) and Youden index (1.355). In addition, it achieved the highest metrics score (63 points), followed by deep neural network (46 points) and random forest (45 points), in the internal validation set. In the external validation set, GBDT still performed comparably, achieving the second highest metrics score (52 points). The high-risk group had more than twice the odds of experiencing medical disputes compared with the low-risk group. CONCLUSIONS: We established a prediction model to stratify medical workers into different risk groups for encountering medical disputes. Among the 5 ML models, GBDT demonstrated the optimal comprehensive performance and was used to construct the web-based app. Our proposed model can serve as a useful tool for identifying medical workers at high risk of medical disputes. We believe that preventive strategies should be implemented for the high-risk group.

Endometrium-derived mesenchymal stem cells suppress progression of endometrial cancer via the DKK1-Wnt/ß-catenin signaling pathway.

BACKGROUND: Mesenchymal stem cell (MSC) therapy is an attractive treatment option for various cancers. Whether MSCs can be used to treat well-differentiated endometrial cancer (EC) remains unclear. The aim of this study is to explore the potential therapeutic effects of MSCs on EC and the underlying mechanisms. METHODS: The effects of adipose-derived MSCs (AD-MSCs), umbilical-cord-derived MSCs (UC-MSCs), and endometrium-derived MSCs (eMSCs) on the malignant behaviors of EC cells were explored via in vitro and in vivo experiments. Three EC models, including patient-derived EC organoid lines, EC cell lines, and EC xenograft model in female BALB/C nude mice, were used for this study. The effects of MSCs on EC cell proliferation, apoptosis, migration, and the growth of xenograft tumors were evaluated. The potential mechanisms by which eMSCs inhibit EC cell proliferation and stemness were explored by regulating DKK1 expression in eMSCs or Wnt signaling in EC cells. RESULTS: Our results showed that eMSCs had the highest inhibitory effect on EC cell viability, and EC xenograft tumor growth in mice compared to AD-MSCs and UC-MSCs. Conditioned medium (CM) obtained from eMSCs significantly suppressed the sphere-forming ability and stemness-related gene expression of EC cells. In comparison to AD-MSCs and UC-MSCs, eMSCs had the highest level of Dickkopf-related protein 1 (DKK1) secretion. Mechanistically, eMSCs inhibited Wnt/ß-catenin signaling in EC cells via secretion of DKK1, and eMSCs suppressed EC cell viability and stemness through DKK1-Wnt/ß-catenin signaling. Additionally, the combination of eMSCs and medroxyprogesterone acetate (MPA) significantly inhibited the viability of EC organoids and EC cells compared with eMSCs or MPA alone. CONCLUSIONS: The eMSCs, but not AD-MSCs or UC-MSCs, could suppress the malignant behaviors of EC both in vivo and in vitro via inhibiting the Wnt/ß-catenin signaling pathway by secreting DKK1. The combination of eMSCs and MPA effectively inhibited EC growth, indicating that eMSCs may potentially be a new therapeutic strategy for young EC patients desiring for fertility preservation.

Enhanced bisphenol S anaerobic degradation using an NZVI-HA-modified anode in bioelectrochemical systems.

As a substitute for bisphenol A (BPA), bisphenol S (BPS) has a longer half-life, higher chemical inertness and better skin permeability than BPA, and it also has a strong endocrine disruption effect. Relatively few studies have focused on the main processing technology for BPS biodegradation, and the findings indicate that the biodegradation efficiency of BPS was relatively low. Therefore, this paper used an NZVI-HA composite-modified bio-anode to enhance the anaerobic degradation of BPS in a Bioelectrochemical Systems (BES). The results showed that the degradation efficiency of BPS was improved from 31.1% to 92.2% with the NZVI-HA modification compared with the control group (CC-BES). FTIR and XPS analyzes demonstrated that HA can accelerate the reduction rate of Fe3+ and increase the ratio of Fe2+/Fe3+. In addition, HA can form Fe-O-HA complexes with NZVI to promote electron transfer. An analysis of the NZVI-HA-BES intermediate metabolites revealed that complex modification properties altered the BPS degradation pathway. An analysis of microbial diversity indicated that the bacteria related to the degradation of BPS may be Terrimonas, Lysobacter, and Acidovorax.

RaxM regulates the AvrXa21 (RaxX)-mediated immune response.

Xanthomonas oryzae pv. oryzae (Xoo) is the causal agent of rice bacterial blight disease, which causes a reduction in rice production. The interaction between Xoo and rice is a model for the study of the gene-for-gene hypothesis, in which a resistance (R) gene encoding a product interacts with an effector molecule encoded by a corresponding bacterial avirulence (avr) gene. Rice XA21 functions as a plant innate immune receptor (R protein) and recognizes the avirulence protein (RaxX) of Xoo to induce the immune response and cope with pathogen attack. The sulphuration of RaxX by the tyrosine sulphotransferase RaxST is essential to its activity. The expression of raxST is regulated by the RaxH/RaxR and phoP/phoQ two-component systems. However, the regulation of raxX expression remains unclear. Here, we showed that a gene (raxM) encodes a small protein, which functions as a regulator of raxX expression. raxX and raxM are located upstream of raxST. Transcriptional analysis indicates that raxX and raxM are separately transcribed and the promoter of raxX is located at the raxM coding region. The RaxM protein regulates its own and raxX expression, and is required for the XA21-mediated immunity response. Therefore, we identified a regulator of raxX expression and of the Xoo-rice interaction. Our findings suggest that RaxX is not only regulated at the post-translational level, but also at the transcriptional level.

Genome-Wide Analysis of ß-Galactosidases in Xanthomonas campestris pv. campestris 8004.

Bacterial ß-galactosidase is involved in lactose metabolism and acts as a prevalent reporter enzyme used in studying the activities of prokaryotic and eukaryotic promoters. Xanthomonas campestris pv. campestris (Xcc) is the pathogen of black rot disease in crucifers. ß-Galactosidase activity can be detected in Xcc culture, which makes Escherichia coli LacZ unable to be used as a reporter enzyme in Xcc. To systemically understand the ß-galactosidase in Xcc and construct a ß-galactosidase -deficient strain for promoter activity analysis using LacZ as a reporter, we here analyzed the putative ß-galactosidases in Xcc 8004. As glycosyl hydrolase (GH) family 2 (GH2) and 35 (GH35) family enzymes were reported to have beta-galactosidase activities, we studied all of them encoded by Xcc 8004. When expressed in E. coli, only two of the enzymes, XC1214 and XC2985, were found to have ß-galactosidase activity. When deleted from the Xcc 8004 genome, only the XC1214 mutant had no ß-galactosidase activity, and other GH2 and GH35 gene deletions resulted in no significant reduction in ß-galactosidase activity. Therefore, XC1214 is the main ß-galactosidase in Xcc 8004. Notably, we have constructed a ß-galactosidase-free strain that can be employed in gene traps using LacZ as a reporter in Xcc. The results reported herein should facilitate the development of high-capacity screening assays that utilize the LacZ reporter system in Xcc.

Immobilized metal ion affinity chromatography ZipTip pipette tip with polydopamine modification and Ti4⁺ immobilization for selective enrichment and isolation of phosphopeptides.

As an effective tool in protein analysis, mass spectroscopy (MS) has been widely used in identifying protein phosphorylation and phosphorylation sites. Because of the low abundance of phosphopeptides in protein digestion, isolation and enrichment of phosphopeptides prior to MS analysis is important for efficient phosphopeptides identification. In this work, we initially immobilized titanium ions on polydopamine (PDA)-modified ZipTip pipette tips (denoted as IMAC ZipTip pipette tip) for simple and quick enrichment of phosphopeptides. The preparation process of the novel ZipTip pipette tips is fast and economic since it only contains two simple steps both with mild conditions. The ability of modified ZipTip pipette tips for identifying phosphopeptides in complex biological samples was investigated. The unique ZipTip pipette tip not only exhibited superior ability in selectively capturing phosphopeptides from large amount of non-phosphopeptides, but also remarkably shortened the MS preparation and analysis time, making it an easy-to-use and efficient tool in phosphoproteome research.

Preparation of on-plate immobilized metal ion affinity chromatography platform via dopamine chemistry for highly selective isolation of phosphopeptides with matrix assisted laser desorption/ionization mass spectrometry analysis.

In this study, a novel on-plate IMAC technique was developed for highly selective enrichment and isolation of phosphopeptides with high-throughput MALDI-TOF-MS analysis. At first, a MALDI plate was coated with polydopamine (PDA), and then Ti(4+) was immobilized on the PDA-coated plate. The obtained IMAC plate was successfully applied to the highly selective enrichment and isolation of phosphopeptides in protein digests and human serum. Because of no loss of samples, the on-plate IMAC platform exhibits excellent selectivity and sensitivity in the selective enrichment and isolation of phosphopeptides, which provides a potential technique for high selectivity in the detection of low-abundance phosphopeptides in biological samples.

Polydopamine-coated eppendorf tubes for Ti4⁺ immobilization for selective enrichment of phosphopeptides.

Mass spectrometric technique has emerged as a preferred technique in the analysis of protein phosphorylation. Owing to the low stoichiometry of phosphopeptides and the signal suppression effect by non-phosphopeptides, there is a demand for efficient enrichment of phosphopeptides. The selective enrichment of phosphopeptides in modified eppendorf tubes prior to mass spectrometry analysis, which can minimize sample loss as well as nonspecific interferences effectively, has become a hot topic in current proteomics field. In our work, an easy-to-use phosphopeptide-selective eppendorf tube was initially prepared, with its inner surface being modified with a Ti(4+)-immobilized polydopamine (PDA) layer. The unique Ti(4+)-immobilized PDA-modified eppendorf tubes (EP tube@PDA-Ti(4+)) are investigated for its application in selective enrichment of phosphopeptides from complex biological samples. Due to the high Ti(4+) loading amount on the surface of PDA, the EP tube@PDA-Ti(4+) exhibits remarkable phosphopeptide enrichment ability in protein digests and human serum, which presents a powerful evidence for its high selectivity in detecting the low-abundance phosphopeptides from complex biological samples.

Hydrophilic polydopamine-coated magnetic graphene nanocomposites for highly efficient tryptic immobilization.

In this work, polydopamine-coated magnetic graphene (MG@PDA) nanocomposites were synthesized by a facile method. Trypsin was then directly immobilized on the surface of the nanocomposites through simple PDA chemistry with no need for introducing any other coupling groups. The as-made MG@PDA nanocomposites inherit not only the large surface area of graphene which makes them capable of immobilizing high amount of trypsin (up to 0.175 mg/mg), but also the good hydrophilicity of PDA which greatly improves their biocompatibility. Moreover, the strong magnetic responsibility makes them easy to be separated from the digested peptide solution when applying a magnetic field. The feasibility of the trypsin-immobilized MG@PDA (MG@PDA-trypsin) nanocomposites for protein digestion was investigated and the results indicated their high digestion efficiency in a short digestion time (10 min). In addition, the reusability and stability of the MG@PDA-trypsin nanocomposites were also tested in our work. To further confirm the efficiency of MG@PDA-trypsin nanocomposites for proteome analysis, they were applied to digest proteins extracted from skimmed milk, followed by nano RPLC-ESI-MS/MS analysis, and a total of 321 proteins were identified, much more than those obtained by 16-h in-solution digestion (264 proteins), indicating the great potential of MG@PDA-trypsin nanocomposites as the supports for high-throughput proteome study.

Synthesis of highly water-dispersible polydopamine-modified multiwalled carbon nanotubes for matrix-assisted laser desorption/ionization mass spectrometry analysis.

In this work, we synthesized highly water-dispersible multiwalled carbon nanotubes@polydopamine (MWCNTs@PDA) core-shell composites by a facile in situ oxidative polymerization. The composites were successfully applied as a novel matrix for the matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) analysis of various water-soluble small molecule compounds. It was found that MWCNTs@PDA composites have a higher sensitivity and peak intensities for small molecules detection.

Enrichment and detection of small molecules using magnetic graphene as an adsorbent and a novel matrix of MALDI-TOF-MS.

Magnetic graphene composites were synthesized via a simple hydrothermal reaction, and the as-made composites were successfully applied as an adsorbent and a novel matrix in the enrichment and analysis of small molecules by matrix assisted laser desorption/ionization mass spectrometry.

Morphine-induced conditioned place preference in mice: metabolomic profiling of brain tissue to find "molecular switch" of drug abuse by gas chromatography/mass spectrometry.

Conditioned place preference (CPP) is a widely used model to explore the mechanism of context-dependent learning. In this work, we developed a GC-MS method to investigate the metabolites in mice brain which was used to study the mechanism of context-dependent learning associated with rewarding effect of morphine. Metabolites were extracted from brain tissues and derivatized followed by analysis by gas chromatography/mass spectrometry (GC-MS). In total, 69 peaks were identified as known compounds. By a Wilcoxon ran sum test with p value ≤0.05, 21 metabolites were selected and considered as the potential biomarkers of morphine in mice brain. Using principal component analysis (PCA) and receiver-operator characteristic (ROC) curves, a model was constructed with a combination of these 21 metabolic markers. Multivariate statistics of the model yielded separation between the two groups with an area under the curve value of 0.947. Some metabolites were further discussed in detail about their pathway. Results showed that our technique can be successfully applied to profile for biomarkers and in understanding molecular mechanisms of drug abuse.

Facile synthesis of water-soluble multi-wall carbon nanotubes and polyaniline composites and their application in detection of small metabolites by matrix assisted laser desorption/ionization mass spectrometry.

Multi-wall carbon nanotubes and polyaniline composites were synthesized via a simple hydrothermal reaction, and the as-made composites were successfully applied in the analysis of small molecular-weight metabolites as a novel matrix by matrix assisted laser desorption/ionization mass spectrometry.

Preparation of Fe3O4@C@PANI magnetic microspheres for the extraction and analysis of phenolic compounds in water samples by gas chromatography-mass spectrometry.

In this work, core-shell structure Fe(3)O(4)@C@polyaniline magnetic microspheres were synthesized using simple hydrothermal reactions. The carbon-coated magnetic microspheres (Fe(3)O(4)@C) were first synthesized by a hydrothermal reaction, and then aniline was polymerized on the magnetic core via another hydrothermal reaction. Then, the obtained Fe(3)O(4)@C@polyaniline magnetic microspheres were applied as magnetic adsorbents for the extraction of aromatic molecules due to π-π interactions between polyaniline shell and aromatic compounds. In our study, five kinds of phenols including phenol, 2,4-dichlorophenol (DCP), 2,4,5-trichlorophenol (TCP), pentachlorophenol (PCP) and bisphenol A (BPA) were selected as the model analytes to verify the extraction ability of Fe(3)O(4)@C@PANI microspheres. After derivatization, the phenols were detected using gas chromatography-mass spectrometry (GC-MS). The dominant parameters affecting enrichment efficiency were investigated and optimized. Under the optimal conditions, the proposed method was evaluated, and applied to the analysis of phenols in real water samples. The results demonstrated that our proposed method based on Fe(3)O(4)@C@polyaniline magnetic microspheres had good linearity (r(2)>0.991), and limits of quantification (2.52-29.7 ng/mL), high repeatability (RSD<13.1%) and good recovery (85.3-110.6%).