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1.
Nat Immunol ; 17(9): 1075-83, 2016 09.
Article in English | MEDLINE | ID: mdl-27400149

ABSTRACT

Adhesion and migration of T cells are controlled by chemokines and by adhesion molecules, especially integrins, and have critical roles in the normal physiological function of T lymphocytes. Using an RNA-mediated interference screen, we identified the WNK1 kinase as a regulator of both integrin-mediated adhesion and T cell migration. We found that WNK1 is a negative regulator of integrin-mediated adhesion, whereas it acts as a positive regulator of migration via the kinases OXSR1 and STK39 and the ion co-transporter SLC12A2. WNK1-deficient T cells home less efficiently to lymphoid organs and migrate more slowly through them. Our results reveal that a pathway previously known only to regulate salt homeostasis in the kidney functions to balance T cell adhesion and migration.


Subject(s)
Cell Adhesion/genetics , Cell Movement/genetics , Minor Histocompatibility Antigens/metabolism , Protein Serine-Threonine Kinases/metabolism , Receptors, Lymphocyte Homing/metabolism , T-Lymphocytes/physiology , Animals , Cells, Cultured , Homeostasis , Ion Transport , Kidney/metabolism , Mice , Mice, Inbred C57BL , Mice, Knockout , Minor Histocompatibility Antigens/genetics , Protein Serine-Threonine Kinases/genetics , RNA Interference , Receptors, Lymphocyte Homing/genetics , Solute Carrier Family 12, Member 2/metabolism , WNK Lysine-Deficient Protein Kinase 1
2.
J Pathol ; 263(1): 99-112, 2024 05.
Article in English | MEDLINE | ID: mdl-38411280

ABSTRACT

Desmoglein-2 (DSG2) is a transmembrane glycoprotein belonging to the desmosomal cadherin family, which mediates cell-cell junctions; regulates cell proliferation, migration, and invasion; and promotes tumor development and metastasis. We previously showed serum DSG2 to be a potential biomarker for the diagnosis of esophageal squamous cell carcinoma (ESCC), although the significance and underlying molecular mechanisms were not identified. Here, we found that DSG2 was increased in ESCC tissues compared with adjacent tissues. In addition, we demonstrated that DSG2 promoted ESCC cell migration and invasion. Furthermore, using interactome analysis, we identified serine/threonine-protein kinase D2 (PRKD2) as a novel DSG2 kinase that mediates the phosphorylation of DSG2 at threonine 730 (T730). Functionally, DSG2 promoted ESCC cell migration and invasion dependent on DSG2-T730 phosphorylation. Mechanistically, DSG2 T730 phosphorylation activated EGFR, Src, AKT, and ERK signaling pathways. In addition, DSG2 and PRKD2 were positively correlated with each other, and the overall survival time of ESCC patients with high DSG2 and PRKD2 was shorter than that of patients with low DSG2 and PRKD2 levels. In summary, PRKD2 is a novel DSG2 kinase, and PRKD2-mediated DSG2 T730 phosphorylation promotes ESCC progression. These findings may facilitate the development of future therapeutic agents that target DSG2 and DSG2 phosphorylation. © 2024 The Pathological Society of Great Britain and Ireland.


Subject(s)
Esophageal Neoplasms , Esophageal Squamous Cell Carcinoma , Humans , Esophageal Squamous Cell Carcinoma/metabolism , Phosphorylation , Protein Kinase D2 , Esophageal Neoplasms/pathology , Cell Line, Tumor , Cell Proliferation/physiology , Serine , Cell Movement/physiology , Gene Expression Regulation, Neoplastic , Desmoglein 2/genetics , Desmoglein 2/metabolism
3.
Exp Cell Res ; 438(2): 114061, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38692345

ABSTRACT

Acute myocardial infarction (AMI) is a prevalent cardiovascular disease with high morbidity and mortality rates worldwide. Pyroptosis is an inflammatory form of programmed cell death that has been linked to various pathological conditions. However, its exact contribution to the onset and progression of heart injury in AMI has not yet fully elucidated. Herein, we established mouse AMI model by ligating the left anterior descending artery and performed transcriptome analysis during the early phase of AMI. Mouse HL-1 and human AC-16 cardiomyocytes were subjected to hypoxia to simulate ischemic injury in vitro. Our results revealed a significant activation of the inflammatory response at 3 h post-ligation, as confirmed by RNA sequencing. We identified the occurrence of NLRP3 inflammasome-mediated pyroptosis in the cardiac tissues of human cases with AMI, as well as in mouse models of AMI and hypoxia-induced cardiomyocytes, using immunohistochemistry staining and Western blotting assays. Concurrently, pharmacological inhibition of NLRP3 inflammasome-mediated pyroptosis with MCC950 and VX-765 effectively decreased hypoxia-induced cardiomyocytes injury, while mitigating myocardial oxidative stress, apoptosis and inflammation caused by hypoxia. Moreover, the circulating levels of gasdermin D (GSDMD), the pyroptosis executor, were remarkably elevated in the plasma of mice with early AMI and in the supernatant of hypoxia-exposed cardiomyocytes in a time-dependent manner using ELISA and Western blotting. Furthermore, the change in circulating GSDMD positively correlated with Creatine Kinase-MB (CK-MB) in the plasma of early-stage AMI mouse. In summary, these findings indicated a critical role for NLRP3 inflammasome-mediated pyroptosis in the progression of AMI, the administration of MCC950 and VX-765 may be attractive candidate therapeutic approaches for cardiac injury caused by acute hypoxia or even AMI. Additionally, the circulating GSDMD exhibits potential as a newly diagnostic biomarker for AMI.


Subject(s)
Apoptosis , Furans , Inflammation , Mice, Inbred C57BL , Myocardial Infarction , Myocytes, Cardiac , Oxidative Stress , Pyroptosis , Sulfonamides , Pyroptosis/drug effects , Animals , Mice , Apoptosis/drug effects , Oxidative Stress/drug effects , Sulfonamides/pharmacology , Humans , Inflammation/metabolism , Inflammation/pathology , Inflammation/drug therapy , Myocytes, Cardiac/metabolism , Myocytes, Cardiac/drug effects , Myocytes, Cardiac/pathology , Male , Furans/pharmacology , Myocardial Infarction/metabolism , Myocardial Infarction/pathology , Myocardial Infarction/drug therapy , Indenes/pharmacology , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , para-Aminobenzoates/pharmacology , Inflammasomes/metabolism , Inflammasomes/drug effects , Disease Models, Animal , Myocardium/metabolism , Myocardium/pathology , Hypoxia/metabolism , Hypoxia/complications , Dipeptides
4.
Gut ; 2024 Jul 27.
Article in English | MEDLINE | ID: mdl-38969490

ABSTRACT

OBJECTIVE: Precancerous metaplasia transition to dysplasia poses a risk for subsequent intestinal-type gastric adenocarcinoma. However, the molecular basis underlying the transformation from metaplastic to cancerous cells remains poorly understood. DESIGN: An integrated analysis of genes associated with metaplasia, dysplasia was conducted, verified and characterised in the gastric tissues of patients by single-cell RNA sequencing and immunostaining. Multiple mouse models, including homozygous conditional knockout Klhl21-floxed mice, were generated to investigate the role of Klhl21 deletion in stemness, DNA damage and tumour formation. Mass-spectrometry-based proteomics and ribosome sequencing were used to elucidate the underlying molecular mechanisms. RESULTS: Kelch-like protein 21 (KLHL21) expression progressively decreased in metaplasia, dysplasia and cancer. Genetic deletion of Klhl21 enhances the rapid proliferation of Mist1+ cells and their descendant cells. Klhl21 loss during metaplasia facilitates the recruitment of damaged cells into the cell cycle via STAT3 signalling. Increased STAT3 activity was confirmed in cancer cells lacking KLHL21, boosting self-renewal and tumourigenicity. Mechanistically, the loss of KLHL21 promotes PIK3CB mRNA translation by stabilising the PABPC1-eIF4G complex, subsequently causing STAT3 activation. Pharmacological STAT3 inhibition by TTI-101 elicited anticancer effects, effectively impeding the transition from metaplasia to dysplasia. In patients with gastric cancer, low levels of KLHL21 had a shorter survival rate and a worse response to adjuvant chemotherapy. CONCLUSIONS: Our findings highlighted that KLHL21 loss triggers STAT3 reactivation through PABPC1-mediated PIK3CB translational activation, and targeting STAT3 can reverse preneoplastic metaplasia in KLHL21-deficient stomachs.

5.
J Am Chem Soc ; 146(5): 3010-3022, 2024 Feb 07.
Article in English | MEDLINE | ID: mdl-38278519

ABSTRACT

The development of Pt-based catalysts for use in fuel cells that meet performance targets of high activity, maximized stability, and low cost remains a huge challenge. Herein, we report a nitrogen (N)-doped high-entropy alloy (HEA) electrocatalyst that consists of a Pt-rich shell and a N-doped PtCoFeNiCu core on a carbon support (denoted as N-Pt/HEA/C). The N-Pt/HEA/C catalyst showed a high mass activity of 1.34 A mgPt-1 at 0.9 V for the oxygen reduction reaction (ORR) in rotating disk electrode (RDE) testing, which substantially outperformed commercial Pt/C and most of the other binary/ternary Pt-based catalysts. The N-Pt/HEA/C catalyst also demonstrated excellent stability in both RDE and membrane electrode assembly (MEA) testing. Using operando X-ray absorption spectroscopy (XAS) measurements and theoretical calculations, we revealed that the enhanced ORR activity of N-Pt/HEA/C originated from the optimized adsorption energy of intermediates, resulting in the tailored electronic structure formed upon N-doping. Furthermore, we showed that the multiple metal-nitrogen bonds formed synergistically improved the corrosion resistance of the 3d transition metals and enhanced the ORR durability.

6.
Ann Surg ; 279(6): 923-931, 2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38375670

ABSTRACT

OBJECTIVE: To assess the effectiveness of indocyanine green (ICG)-guided lymph node (LN) dissection during laparoscopic radical gastrectomy after neoadjuvant chemotherapy (NAC) in patients with locally advanced gastric cancer (LAGC). BACKGROUND: Studies on ICG imaging use in patients with LAGC on NAC are rare. METHODS: Patients with gastric adenocarcinoma (clinical T2-4NanyM0) who received NAC were randomly assigned to receive ICG-guided laparoscopic radical gastrectomy or laparoscopic radical gastrectomy alone. Here, we reported the secondary endpoints including the quality of lymphadenectomy (total retrieved LNs and LN noncompliance) and surgical outcomes. RESULTS: Overall, 240 patients were randomized. Of whom, 236 patients were included in the primary analysis (118 in the ICG group and 118 in the non-ICG group). In the ICG group, the mean number of LNs retrieved was significantly higher than in the non-ICG group within the D2 dissection (48.2 vs 38.3, P < 0.001). The ICG fluorescence guidance significantly decreased the LN noncompliance rates (33.9% vs 55.1%, P = 0.001). In 165 patients without baseline measurable LNs, ICG significantly increased the number of retrieved LNs and decreased the LN noncompliance rate ( P < 0.05). For 71 patients with baseline measurable LNs, the quality of lymphadenectomy significantly improved in those who had a complete response ( P < 0.05) but not in those who did not ( P > 0.05). Surgical outcomes were comparable between the groups ( P > 0.05). CONCLUSIONS: ICG can effectively improve the quality of lymphadenectomy in patients with LAGC who underwent laparoscopic radical gastrectomy after NAC.


Subject(s)
Adenocarcinoma , Gastrectomy , Indocyanine Green , Laparoscopy , Lymph Node Excision , Neoadjuvant Therapy , Stomach Neoplasms , Humans , Indocyanine Green/administration & dosage , Stomach Neoplasms/surgery , Stomach Neoplasms/pathology , Stomach Neoplasms/drug therapy , Lymph Node Excision/methods , Male , Laparoscopy/methods , Female , Middle Aged , Gastrectomy/methods , Aged , Adenocarcinoma/surgery , Adenocarcinoma/drug therapy , Adenocarcinoma/pathology , Coloring Agents/administration & dosage , Adult , Treatment Outcome , Neoplasm Staging , Chemotherapy, Adjuvant
7.
Eur J Immunol ; 53(1): e2250011, 2023 01.
Article in English | MEDLINE | ID: mdl-36250416

ABSTRACT

Gasdermin D (GSDMD) is a classical molecule involved in pyroptosis. It has been reported to be cleaved into N-terminal fragments to form pores in the neutrophil membrane and promote the release of neutrophil extracellular traps (NETs). However, it remains unclear if GSDMD is involved in neutrophil regulation and NET release during ARDS. The role of neutrophil GSDMD in the development of ARDS was investigated in a murine model of ARDS induced by lipopolysaccharide (LPS) using the neutrophil specific GSDMD-deficient mice. The neutrophil GSDMD cleavage and its relationship with NETosis were also explored in ARDS patients. The cleavage of GSDMD in neutrophils from ARDS patients and mice was upregulated. Inhibition of GSDMD by genetic knockout or inhibitors resulted in reduced production of NET both in vivo and in vitro, and attenuation of LPS-induced lung injury. Moreover, in vitro experiments showed that the inhibition of GSDMD attenuated endothelial injury co-cultured with neutrophils from ARDS patients, while extrinsic NETs reversed the protective effect of GSDMD inhibition. Collectively, our data suggest that the neutrophil GSDMD cleavage is crucial in NET release during ARDS. The NET release maintained by cleaved GSDMD in neutrophils may be a key event in the development of ARDS.


Subject(s)
Extracellular Traps , Respiratory Distress Syndrome , Mice , Animals , Lipopolysaccharides , Neutrophils , Pyroptosis
8.
BMC Plant Biol ; 24(1): 683, 2024 Jul 18.
Article in English | MEDLINE | ID: mdl-39020306

ABSTRACT

Campanumoea javanica Bl. (CJ) traditionally used in Southwestern China, is now widely consumed as a health food across the nation. Due to its similar efficacy to Codonopsis Radix (CR) and their shared botanical family, CJ is often used as a substitute for CR. According to the Chinese Pharmacopoeia, Codonopsis pilosula var. modesta (Nannf.) L.T. Shen (CPM), Codonopsis pilosula (Franch.) Nannf. (CP), and Codonopsis tangshen Oliv. (CT) are the primary sources of CR. However, details on the differences in composition, effectiveness, and compositional between CJ and CR are still limited. Besides, there is little evidence to support the application of CJ as a drug. In this study, we employed widely targeted metabolomics, network pharmacology analysis, and molecular docking to explore the disparities in metabolite profiles between CJ and CR and to predict the pharmacological mechanisms of the dominant differential metabolites of CJ and their potential medicinal applications. The widely targeted metabolomics results indicated that 1,076, 1,102, 1,102, and 1,093 compounds, most phenolic acids, lipids, amino acids, and flavonoids, were characterized in CJ, CPM, CP, and CT, respectively. There were an average of 1061 shared compounds in CJ and CRs, with 95.07% similarity in metabolic profiles. Most of the metabolites in CJ were previously unreported. Twelve of the seventeen dominant metabolites found in CJ were directly associated with treating cancer and lactation, similar to the traditional medicinal efficacy. The molecular docking results showed that the dominant metabolites of CJ had good docking activity with the core targets PIK3R1, PIK3CA, ESR1, HSP90AA1, EGFR, and AKT1. This study provides a scientific basis for understanding the similarities and differences between CJ and CR at the metabolome level, offering a theoretical foundation for developing innovative medications from CJ. Additionally, it significantly enhances the metabolite databases for both CJ and CR.


Subject(s)
Codonopsis , Metabolomics , Network Pharmacology , Codonopsis/chemistry , Codonopsis/metabolism , Molecular Docking Simulation , Drugs, Chinese Herbal/metabolism , Drugs, Chinese Herbal/pharmacology , Drugs, Chinese Herbal/chemistry , Plant Roots/metabolism , Plant Extracts/pharmacology , Plant Extracts/chemistry , Plant Extracts/metabolism
9.
Small ; : e2402655, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38949408

ABSTRACT

Solution Gated Graphene Field-Effect Transistors (SGGT) are eagerly anticipated as an amplification platform for fabricating advanced ultra-sensitive sensors, allowing significant modulation of the drain current with minimal gate voltage. However, few studies have focused on light-matter interplay gating control for SGGT. Herein, this challenge is addressed by creating an innovative photoelectrochemical solution-gated graphene field-effect transistor (PEC-SGGT) functionalized with enzyme cascade reactions (ECR) for Organophosphorus (OPs) detection. The ECR system, consisting of acetylcholinesterase (AChE) and CuBTC nanomimetic enzymes, selectively recognizes OPs and forms o-phenylenediamine (oPD) oligomers sediment on the PEC electrode, with layer thickness related to the OPs concentration, demonstrating time-integrated amplification. Under light stimulation, the additional photovoltage generated on the PEC gate electrode is influenced by the oPD oligomers sediment layer, creating a differentiated voltage distribution along the gate path. PEC-SGGT, inherently equipped with built-in amplification circuits, sensitively captures gate voltage changes and delivers output with an impressive thousandfold current gain. The seamless integration of these three amplification modes in this advanced sensor allows a good linear range and highly sensitive detection of OPs, with a detection limit as low as 0.05 pm. This work provides a proof-of-concept for the feasibility of light-assisted functionalized gate-controlled PEC-SGGT for small molecule detection.

10.
Bioinformatics ; 39(4)2023 04 03.
Article in English | MEDLINE | ID: mdl-37018146

ABSTRACT

SUMMARY: We developed the eccDB database to integrate available resources for extrachromosomal circular DNA (eccDNA) data. eccDB is a comprehensive repository for storing, browsing, searching, and analyzing eccDNAs from multispecies. The database provides regulatory and epigenetic information on eccDNAs, with a focus on analyzing intrachromosomal and interchromosomal interactions to predict their transcriptional regulatory functions. Moreover, eccDB identifies eccDNAs from unknown DNA sequences and analyzes the functional and evolutionary relationships of eccDNAs among different species. Overall, eccDB offers web-based analytical tools and a comprehensive resource for biologists and clinicians to decipher the molecular regulatory mechanisms of eccDNAs. AVAILABILITY AND IMPLEMENTATION: eccDB is freely available at http://www.xiejjlab.bio/eccDB.


Subject(s)
Chromatin , DNA, Circular , Chromatin/genetics , Chromosomes , DNA , Base Sequence
11.
J Transl Med ; 22(1): 248, 2024 Mar 07.
Article in English | MEDLINE | ID: mdl-38454480

ABSTRACT

BACKGROUND: Acute ischemic stroke is a common neurological disease with a significant financial burden but lacks effective drugs. Hypoxia-inducible factor (HIF) and prolyl hydroxylases (PHDs) participate in the pathophysiological process of ischemia. However, whether FG4592, the first clinically approved PHDs inhibitor, can alleviate ischemic brain injury remains unclear. METHODS: The infarct volumes and behaviour tests were first analyzed in mice after ischemic stroke with systemic administration of FG4592. The knockdown of HIF-1α and pretreatments of HIF-1/2α inhibitors were then used to verify whether the neuroprotection of FG4592 is HIF-dependent. The targets predicting and molecular docking methods were applied to find other targets of FG4592. Molecular, cell biological and gene knockdown methods were finally conducted to explore the potential neuroprotective mechanisms of FG4592. RESULTS: We found that the systemic administration of FG4592 decreased infarct volume and improved neurological defects of mice after transient or permanent ischemia. Meanwhile, FG4592 also activated autophagy and inhibited apoptosis in peri-infarct tissue of mice brains. However, in vitro and in vivo results suggested that the neuroprotection of FG4592 was not classical HIF-dependent. 2-oxoglutarate and iron-dependent oxygenase domain-containing protein 1 (OGFOD1) was found to be a novel target of FG4592 and regulated the Pro-62 hydroxylation in the small ribosomal protein s23 (Rps23) with the help of target predicting and molecular docking methods. Subsequently, the knockdown of OGFOD1 protected the cell against ischemia/reperfusion injury and activated unfolded protein response (UPR) and autophagy. Moreover, FG4592 was also found to activate UPR and autophagic flux in HIF-1α independent manner. Blocking UPR attenuated the neuroprotection, pro-autophagy effect and anti-apoptosis ability of FG4592. CONCLUSION: This study demonstrated that FG4592 could be a candidate drug for treating ischemic stroke. The neuroprotection of FG4592 might be mediated by inhibiting alternative target OGFOD1, which activated the UPR and autophagy and inhibited apoptosis after ischemic injury. The inhibition of OGFOD1 is a novel therapy for ischemic stroke.


Subject(s)
Brain Ischemia , Ischemic Stroke , Stroke , Mice , Animals , Neuroprotection , Molecular Docking Simulation , Unfolded Protein Response , Ischemia , Autophagy , Infarction , Brain Ischemia/complications , Brain Ischemia/drug therapy , Brain Ischemia/metabolism , Stroke/drug therapy , Stroke/metabolism , Hypoxia-Inducible Factor 1, alpha Subunit/metabolism
13.
Ann Surg Oncol ; 31(5): 3005-3016, 2024 May.
Article in English | MEDLINE | ID: mdl-38270825

ABSTRACT

BACKGROUND: Sarcopenia is closely associated with gastric cancer (GC) prognosis. However, its exact definition remains controversial. METHODS: This study included computed tomography images and clinical data of patients from three prospective studies. The skeletal muscle index (SMI) and skeletal muscle radiation attenuation (SMRA) were analyzed, and a new muscle parameter, skeletal muscle gauge (SMG), was obtained by multiplying the two parameters. The values of the three indices for predicting the prognosis of patients with GC were compared. RESULTS: The study included 717 patients. The findings showed median values of 42 cm2/m2 (range, 36.8-48.2 cm2/m2) for SMI, 45 HU (range, 41-49 HU) for SMRA, and 1842 (range, 1454-2260) for SMG. Postoperatively, 111 patients (15.5%) experienced complications. The 3-year overall survival (OS), disease-free survival (DFS), and recurrence-free survival (RFS) were 74.3%, 68.2%, and 70%, respectively. Univariate logistic analysis showed that postoperative complications were associated with SMI (odds ratio [OR] 0.94; 95% confidence interval [CI] 0.92-0.96), SMRA (OR, 0.87; 95% CI 0.84-0.90), and SMG (OR 0.99; 95% CI 0.98-0.99). After a two-step multivariate analysis, only SMG (OR 0.98, 95% CI 0.97-0.99) was an independent protective factor of postoperative complications. Multivariate analysis showed that SMG also was an independent protective factor of OS, DFS, and RFS. The patients were divided into low-SMG (L-SMG) group and high-SMG (H-SMG) groups. Chemotherapy benefit analysis of the patients with stage II low SMG showed that the OS, DFS, and RFS of the chemotherapy group were significantly better than those of the non-chemotherapy group (p < 0.05). CONCLUSION: The prospective large sample data showed that the new muscle parameter, SMG, can effectively predict the short-term outcome and long-term prognosis of patients with resectable gastric cancer. As a new muscle parameter index, SMG is worthy of further study.


Subject(s)
Sarcopenia , Stomach Neoplasms , Humans , Prospective Studies , Muscle, Skeletal/pathology , Sarcopenia/complications , Prognosis , Postoperative Complications/etiology , Retrospective Studies
14.
Acc Chem Res ; 56(3): 332-349, 2023 Feb 07.
Article in English | MEDLINE | ID: mdl-36689780

ABSTRACT

ConspectusCatalytic asymmetric hydrogenation is one of the most reliable, powerful, and environmentally benign methods for the synthesis of chiral molecules with high atom economy and has been successfully applied in the industrial production of pharmaceuticals, agrochemicals, and fragrances. The key to achieving highly efficient and highly enantioselective hydrogenation reactions is the design and synthesis of chiral catalysts.Our recent studies involving iridium complexes of bidentate chiral spiro aminophosphine ligands (Ir-SpiroAP) have revealed that adding another coordinating group on the nitrogen atom to form a tridentate ligand can provide catalysts with markedly higher stability, enantioselectivity, and efficiency. Specifically, chiral Ir-SpiroAP catalysts bearing an added pyridine group (designated Ir-SpiroPAP) exhibit high activity and excellent enantioselectivity in the asymmetric hydrogenation of a wide range of carbonyl compounds, including aryl ketones, ß- and δ-ketoesters, α,ß-unsaturated ketones and esters, and racemic α-substituted lactones, as well as highly electron-deficient alkenes such as α,ß-unsaturated malonates and analogues. The efficiency of the Ir-SpiroPAP catalysts is extremely high: in the hydrogenation of aryl ketones, turnover numbers reach 4.5 million, which is the highest value reported to date for a molecular catalyst. Moreover, when a thioether or a bulky triarylphosphine group is added to afford tridentate ligands designated SpiroSAP and SpiroPNP, respectively, the resulting iridium catalysts show high efficiency and enantioselectivity for asymmetric hydrogenation of ß-alkyl-ß-ketoesters and dialkyl ketones, which are challenging substrates. Furthermore, chiral spiro catalysts containing an added oxazoline moiety (Ir-SpiroOAP) show high enantioselectivity for asymmetric hydrogenation of α-keto amides and racemic α-aryloxy lactones. The above-described catalysts have been used for enantioselective synthesis of chiral pharmaceuticals and other bioactive compounds.We have shown that chiral spiro ligands that combine a rigid skeleton with tridentate coordination stabilize iridium catalysts. The careful tailoring of the substituents on the ligand creates a chiral environment around the active metal center of the catalyst that can precisely discriminate between the two faces of a substrate carbonyl group. These factors are key for controlling the activity, enantioselectivity, and turnover numbers of asymmetric hydrogenation catalysts. We expect that catalysts based on iridium, and other transition metals, coordinated by tridentate chiral ligands with a rigid skeleton will find more applications in asymmetric hydrogenation and other asymmetric transformations.

15.
BMC Cancer ; 24(1): 226, 2024 Feb 16.
Article in English | MEDLINE | ID: mdl-38365617

ABSTRACT

BACKGROUND: Systemic inflammatory factors can predict the survival prognosis of gastric cancer (GC) patients after neoadjuvant chemotherapy (NACT). However, whether longitudinal changes in systemic inflammatory factors are associated with short - and long-term outcomes has not been reported. METHODS: This study is a retrospective analysis of 216 patients with advanced gastric cancer who received NACT between January 2011 and June 2019, comparing receiver operating characteristic (ROC) curves for screening suitable inflammatory markers. Group-based trajectory modeling (GBTM) was used to analyze longitudinal changes in inflammatory markers during NACT to identify different potential subgroups and to compare postoperative complications, recurrence-free survival (RFS), and overall survival (OS) among subgroups. RESULTS: Ultimately, neutrophil-lymphocyte ratio (NLR) had the highest area under the curve (AUC) value in predicting prognosis was included in the GBTM analysis. Three trajectories of NLR were obtained: Stable group (SG) (n = 89), Ascent-descend group (ADG) (n = 80) and Continuous descend group (CDG) (n = 47). Compared with SG, ADG and CDG are associated with an increased risk of postoperative recurrence and death. The median time of RFS and OS of SG was longer than that of ADG and CDG (median RFS 81 vs. 44 and 22 months; median OS 69 vs. 41 and 30 months). In addition, CDG had significantly higher postoperative serious complications than SG and ADG (17 (36.2%) vs. 17 (19.1%) and 12 (15.0%); p = 0.005). CONCLUSION: There were different trajectories of NLR during NACT, and these potential trajectories were significantly associated with severe postoperative complications, recurrence, and mortality in patients with GC.


Subject(s)
Neutrophils , Stomach Neoplasms , Humans , Stomach Neoplasms/drug therapy , Stomach Neoplasms/surgery , Retrospective Studies , Neoadjuvant Therapy , Lymphocytes , Prognosis , Postoperative Complications
16.
Anal Biochem ; 689: 115492, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38458307

ABSTRACT

DNA 4 mC plays a crucial role in the genetic expression process of organisms. However, existing deep learning algorithms have shortcomings in the ability to represent DNA sequence features. In this paper, we propose a 4 mC site identification algorithm, DNABert-4mC, based on a fusion of the pruned pre-training DNABert-Pruning model and artificial feature encoding to identify 4 mC sites. The algorithm prunes and compresses the DNABert model, resulting in the pruned pre-training model DNABert-Pruning. This model reduces the number of parameters and removes redundancy from output features, yielding more precise feature representations while upholding accuracy.Simultaneously, the algorithm constructs an artificial feature encoding module to assist the DNABert-Pruning model in feature representation, effectively supplementing the information that is missing from the pre-trained features. The algorithm also introduces the AFF-4mC fusion strategy, which combines artificial feature encoding with the DNABert-Pruning model, to improve the feature representation capability of DNA sequences in multi-semantic spaces and better extract 4 mC sites and the distribution of nucleotide importance within the sequence. In experiments on six independent test sets, the DNABert-4mC algorithm achieved an average AUC value of 93.81%, outperforming seven other advanced algorithms with improvements of 2.05%, 5.02%, 11.32%, 5.90%, 12.02%, 2.42% and 2.34%, respectively.


Subject(s)
Algorithms , DNA , DNA/genetics , Nucleotides
17.
Psychol Med ; 54(6): 1113-1121, 2024 Apr.
Article in English | MEDLINE | ID: mdl-37921013

ABSTRACT

BACKGROUND: Non-suicidal self-injury (NSSI) is prevalent in major depressive disorder (MDD) during adolescence, but the underlying neural mechanisms are unclear. This study aimed to investigate microstructural abnormalities in the cingulum bundle associated with NSSI and its clinical characteristics. METHODS: 130 individuals completed the study, including 35 healthy controls, 47 MDD patients with NSSI, and 48 MDD patients without NSSI. We used tract-based spatial statistics (TBSS) with a region of interest (ROI) analysis to compare the fractional anisotropy (FA) of the cingulum bundle across the three groups. receiver-operating characteristics (ROC) analysis was employed to evaluate the ability of the difficulties with emotion regulation (DERS) score and mean FA of the cingulum to differentiate between the groups. RESULTS: MDD patients with NSSI showed reduced cingulum integrity in the left dorsal cingulum compared to MDD patients without NSSI and healthy controls. The severity of NSSI was negatively associated with cingulum integrity (r = -0.344, p = 0.005). Combining cingulum integrity and DERS scores allowed for successful differentiation between MDD patients with and without NSSI, achieving a sensitivity of 70% and specificity of 83%. CONCLUSIONS: Our study highlights the role of the cingulum bundle in the development of NSSI in adolescents with MDD. The findings support a frontolimbic theory of emotion regulation and suggest that cingulum integrity and DERS scores may serve as potential early diagnostic tools for identifying MDD patients with NSSI.


Subject(s)
Depressive Disorder, Major , Self-Injurious Behavior , White Matter , Humans , Adolescent , Depressive Disorder, Major/diagnostic imaging , White Matter/diagnostic imaging , Depression , Diffusion Tensor Imaging , Self-Injurious Behavior/diagnostic imaging , Anisotropy
18.
J Magn Reson Imaging ; 2024 Jan 23.
Article in English | MEDLINE | ID: mdl-38263789

ABSTRACT

BACKGROUND: Insular low-grade gliomas (LGGs) are surgically challenging due to their proximity to critical structures like the corticospinal tract (CST). PURPOSE: This study aims to determine if preoperative CST shape metrics correlate with postoperative motor complications in insular LGG patients. STUDY TYPE: Retrospective. POPULATION: 42 patients (mean age 40.26 ± 10.21 years, 25 male) with insular LGGs. FIELD STRENGTH/SEQUENCE: Imaging was performed using 3.0 Tesla MRI, incorporating T1-weighted magnetization-prepared rapid gradient-echo, T2-weighted space dark-fluid with spin echo (SE), and diffusional kurtosis imaging (DKI) with gradient echo sequences, all integrated with echo planar imaging. ASSESSMENT: Shape metrics of the CST, including span, irregularity, radius, and irregularity of end regions (RER and IER, respectively), were compared between the affected and healthy hemispheres. Total end region radius (TRER) was determined as the sum of RER 1 and RER 2. The relationships between shape metrics and postoperative short-term (4 weeks) and long-term (>8 weeks) motor disturbances assessing by British Medical Research Council grading system, was analyzed using multivariable regression models. STATISTICAL TESTING: Paired t-tests compared CST metrics between hemispheres. Logistic regression identified associations between these metrics and motor disturbances. The models were developed using all available data and there was no independent validation dataset. Significance was set at P < 0.05. RESULTS: Short-term motor disturbance risk was significantly related to TRER (OR = 199.57). Long-term risk significantly correlated with IER 1 (OR = 59.84), confirmed as a significant marker with an AUC of 0.78. Furthermore, the CST on the affected side significantly had the greater irregularity, larger TRER and RER 1, and smaller span compared to the healthy side. DATA CONCLUSION: Preoperative evaluation of TRER and IER 1 metrics in the CST may serve as a tool for assessing the risk of postoperative motor complications in insular LGG patients. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY: Stage 2.

19.
Mol Cell Biochem ; 2024 Apr 02.
Article in English | MEDLINE | ID: mdl-38564125

ABSTRACT

Osteosarcoma (OS) is a malignant bone sarcoma arising from mesenchymal stem cells. The biological role of Acyl-CoA synthetase long-chain family member 4 (ACSL4), recently identified as an oncogene in numerous tumor types, remains largely unclear in OS. In this study, we investigated the expression of ACSL4 in OS tissues using immunohistochemistry staining (IHC) staining of a human tissue microarray and in OS cells by qPCR assay. Our findings revealed a significant up-regulation of ACSL4 in both OS tissues and cells. To further understand its biological effects, we conducted a series of loss-of-function experiments using ACSL4-depleted MNNG/HOS and U-2OS cell lines, focusing on OS cell proliferation, migration, and apoptosis in vitro. Our results demonstrated that ACSL4 knockdown remarkably suppressed OS cell proliferation, arrested cells in the G2 phase, induced cell apoptosis, and inhibited cell migration. Additionally, a subcutaneous xenograft mice model was established to validate the in vivo impact of ACSL4, revealing ACSL4 silencing impaired tumor growth in the OS xenograft mice. Additionally, we discovered that ACSL4 could regulate the phosphorylation level of Smad2 through cooperative interactions, and treatment with a TGF-ß inhibitor weakened the promoting effects of ACSL4 overexpression. In short, ACSL4 regulated OS progression by modulating TGF-ß/Smad2 signaling pathway. These findings underscore ACSL4 as a promising therapeutic target for OS patients and contribute novel insights into the pathogenesis of OS.

20.
J Neurooncol ; 166(1): 155-165, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38150062

ABSTRACT

OBJECTIVES: This study aims to explore the relationship between the methylation levels of the O-6-methylguanine-DNA methyltransferase (MGMT) promoter and the structural connectivity in insular gliomas across hemispheres. METHODS: We analyzed 32 left and 29 right insular glioma cases and 50 healthy controls, using differential tractography, correlational tractography, and graph theoretical analysis to investigate the correlation between structural connectivity and the methylation level. RESULTS: The differential tractography results revealed that in left insular glioma, the volume of affected inferior fronto-occipital fasciculus (IFOF, p = 0.019) significantly correlated with methylation levels. Correlational tractography results showed that the quantitative anisotropy (QA) value of peritumoral fiber tracts also exhibited a significant correlation with methylation levels (FDR < 0.05). On the other hand, in right insular glioma, anterior internal part of the reticular tract, IFOF, and thalamic radiation showed a significant correlation with methylation levels but at a different correlation direction from the left side (FDR < 0.05). The graph theoretical analysis showed that in the left insular gliomas, only the radius of graph was significantly lower in methylated MGMT group than unmethylated group (p = 0.047). No significant correlations between global properties and methylation levels were observed in insular gliomas on both sides. CONCLUSION: Our findings highlight a significant, hemisphere-specific correlation between MGMT promoter methylation and structural connectivity in insular gliomas. This study provides new insights into the genetic influence on glioma pathology, which could inform targeted therapeutic strategies.


Subject(s)
Brain Neoplasms , Glioma , Humans , DNA Methylation , Glioma/diagnostic imaging , Glioma/genetics , Glioma/drug therapy , DNA Repair Enzymes/genetics , O(6)-Methylguanine-DNA Methyltransferase/genetics , DNA Modification Methylases/genetics , Promoter Regions, Genetic , Brain Neoplasms/diagnostic imaging , Brain Neoplasms/genetics , Brain Neoplasms/pathology , Tumor Suppressor Proteins/genetics
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