Targeted covalent inhibitors, primarily targeting cysteine residues, have attracted great attention as potential drug candidates due to good potency and prolonged duration of action. However, their discovery is challenging. In this research, a database-assisted liquid chromatography-tandem mass spectrometry (LC-MS/MS) strategy was developed to quickly discover potential cysteine-targeting compounds. First, compounds with potential reactive groups were selected and incubated with N-acetyl-cysteine in microsomes. And the precursor ions of possible cysteine-adducts were predicted based on covalent binding mechanisms to establish in-house database. Second, substrate-independent product ions produced from N-acetyl-cysteine moiety were selected. Third, multiple reaction monitoring scan was conducted to achieve sensitive screening for cysteine-targeting compounds. This strategy showed broad applicability, and covalent compounds with diverse structures were screened out, offering structural resources for covalent inhibitors development. Moreover, the screened compounds, norketamine and hydroxynorketamine, could modify synaptic transmission-related proteins in vivo, indicating their potential as covalent inhibitors. This experimental-based screening strategy provides a quick and reliable guidance for the design and discovery of covalent inhibitors.

Targeted covalent inhibitors,primarily targeting cysteine residues,have attracted great attention as potential drug candidates due to good potency and prolonged duration of action.However,their dis-covery is challenging.In this research,a database-assisted liquid chromatography-tandem mass spec-trometry(LC-MS/MS)strategy was developed to quickly discover potential cysteine-targeting compounds.First,compounds with potential reactive groups were selected and incubated with N-acetyl-cysteine in microsomes.And the precursor ions of possible cysteine-adducts were predicted based on covalent binding mechanisms to establish in-house database.Second,substrate-independent product ions produced from N-acetyl-cysteine moiety were selected.Third,multiple reaction monitoring scan was conducted to achieve sensitive screening for cysteine-targeting compounds.This strategy showed broad applicability,and covalent compounds with diverse structures were screened out,offering structural resources for covalent inhibitors development.Moreover,the screened compounds,norket-amine and hydroxynorketamine,could modify synaptic transmission-related proteins in vivo,indicating their potential as covalent inhibitors.This experimental-based screening strategy provides a quick and reliable guidance for the design and discovery of covalent inhibitors.

This study was aimed at identifying the pathogenic bacteria responsible for the death of a young tiger at the Fujian Meihua Mountain South China Tiger Breeding Research Institute.Tissue samples from the lungs,liver,and intestines of the deceased tiger were collected,and the bacteria were cultured inasterile environment.The bacterial strains were characterized according to their morphological and molecular biological properties,including assessment of virulence genes and antibiotic resistance genes,mouse lethality tests,and antibiotic susceptibility evaluations.A predominant bacterial strain isolated from the liver of the deceased tiger was identified as enterotoxigenic Escherichia coli(ETEC)strain Tiger22513F.Phylogenetic analysis of the 16S rRNA gene revealed that the Tiger22513F strain exhibited close genetic similarity to the reference strain ETEC(MF919609.1),with 99.9%nucleotide similarity,and resided on the same evolutionary branch.The Tiger22513F strain contained 11 antibiotic resistance genes(tetA,sul1,sul3,cmlA,floR,blaTEM,blaSHV,blaCMY-2,qnrA,qnrS,and qnrD)along with five virulence genes(VT1,fyuA,tsh,iucD,and ST).Mouse lethality tests indicated significant pathogenicity toward mice,affecting primarily the lungs,liver,and intestines.Antibiotic susceptibility testing demonstrated that this strain exhibited resistance to various classes of beta-lactam antibiotics,as well as quinolones and aminoglycosides.This investigation successfully isolated a multi-drug resistant enterotoxigenic Escherichia coli strain with pronounced pathogenicity from the liver of a deceased tiger;thus providing valuable scientific insights for clinical diagnosis,as well as prevention and control measures,against ETEC infections in South China tigers.

This study was aimed at identifying the pathogenic bacteria responsible for the death of a young tiger at the Fujian Meihua Mountain South China Tiger Breeding Research Institute.Tissue samples from the lungs,liver,and intestines of the deceased tiger were collected,and the bacteria were cultured inasterile environment.The bacterial strains were characterized according to their morphological and molecular biological properties,including assessment of virulence genes and antibiotic resistance genes,mouse lethality tests,and antibiotic susceptibility evaluations.A predominant bacterial strain isolated from the liver of the deceased tiger was identified as enterotoxigenic Escherichia coli(ETEC)strain Tiger22513F.Phylogenetic analysis of the 16S rRNA gene revealed that the Tiger22513F strain exhibited close genetic similarity to the reference strain ETEC(MF919609.1),with 99.9%nucleotide similarity,and resided on the same evolutionary branch.The Tiger22513F strain contained 11 antibiotic resistance genes(tetA,sul1,sul3,cmlA,floR,blaTEM,blaSHV,blaCMY-2,qnrA,qnrS,and qnrD)along with five virulence genes(VT1,fyuA,tsh,iucD,and ST).Mouse lethality tests indicated significant pathogenicity toward mice,affecting primarily the lungs,liver,and intestines.Antibiotic susceptibility testing demonstrated that this strain exhibited resistance to various classes of beta-lactam antibiotics,as well as quinolones and aminoglycosides.This investigation successfully isolated a multi-drug resistant enterotoxigenic Escherichia coli strain with pronounced pathogenicity from the liver of a deceased tiger;thus providing valuable scientific insights for clinical diagnosis,as well as prevention and control measures,against ETEC infections in South China tigers.

OBJECTIVE: To explore the specific pharmacological molecular mechanisms of Laoke Formula (LK) on treating advanced non-small cell lung cancer (NSCLC) based on clinical application, network pharmacology and experimental validation. METHODS: Kaplan-Meier method and Cox regression analysis were used to evaluate the survival benefit of Chinese medicine (CM) treatment in 296 patients with NSCLC in Tianjin Medical University Cancer Institute and Hospital from January 2011 to December 2015. The compounds of LK were screened using the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform, and the corresponding targets were performed from Swiss Target Prediction. NSCLC-related targets were obtained from Therapeutic Target Database and Comparative Toxicogenomics Database. Key compounds and targets were identified from the compound-target-disease network and protein-protein interaction (PPI) network analysis, respectively. Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) enrichment analysis were used to predict the potential signaling pathways involved in the treatment of advanced NSCLC with LK. The binding affinities between key ingredients and targets were further verified using molecular docking. Finally, A549 cell proliferation and migration assay were used to evaluate the antitumor activity of LK. Western blot was used to further verify the expression of key target proteins related to the predicted pathways. RESULTS: Kaplan-Meier survival analysis showed that the overall survival of the CM group was longer than that of the non-CM group (36 months vs. 26 months), and COX regression analysis showed that LK treatment was an independent favorable prognostic factor (P=0.027). Next, 97 components and 86 potential targets were included in the network pharmacology, KEGG and GO analyses, and the results indicated that LK was associated with proliferation and apoptosis. Moreover, molecular docking revealed a good binding affinity between the key ingredients and targets. In vitro, A549 cell proliferation and migration assay showed that the biological inhibition effect was more obvious with the increase of LK concentration (P<0.05). And decreased expressions of nuclear factor κB1 (NF-κB1), epidermal growth factor receptor (EGFR) and AKT serine/threonine kinase 1 (AKT1) and increased expression of p53 (P<0.05) indicated the inhibitory effect of LK on NSCLC by Western blot. CONCLUSION LK inhibits NSCLC by inhibiting EGFR/phosphoinositide 3-kinase (PI3K)/AKT signaling pathway, NFκB signaling pathway and inducing apoptosis, which provides evidence for the therapeutic mechanism of LK to increase overall survival in NSCLC patients.
Humans ; Carcinoma, Non-Small-Cell Lung/metabolism* ; Lung Neoplasms/pathology* ; Drugs, Chinese Herbal/therapeutic use* ; Network Pharmacology ; Female ; Male ; Molecular Docking Simulation ; Middle Aged ; Protein Interaction Maps/drug effects* ; A549 Cells ; Cell Proliferation/drug effects* ; Signal Transduction/drug effects* ; Cell Movement/drug effects* ; Kaplan-Meier Estimate ; Aged ; ErbB Receptors/metabolism*

As a unique gene in the genome,FLASH(FADD-like interleukin-1β-converting enzyme asso-ciated huge protein)/CASP8AP2 is involved in multiple cellular processes,including apoptosis,histone gene pre-mRNA processing,transcriptional regulation,and cell cycle progression.Clinical studies have shown that FLASH is a valuable prognostic marker for acute lymphoblastic leukemia,and a crucial factor for the survival of various cancer cells.Therefore,in-depth research into the function of FLASH may offer new perspectives for the treatment of related diseases.Our previous research identified FLASH as a bind-ing partner of p53,demonstrating that FLASH enhances the transcriptional activity of p53.Here we fur-ther investigate the molecular mechanisms of the interaction between FLASH and p53,revealing that the p53-K386R mutation(SUMOylation residue)attenuated its interaction with FLASH(aa 51-200)and FLASH-SIM(SUMO-interacting motif)(aa 1 534-1 806)significantly.However,SUMO can bind to FLASH-SIM directly,instead of FLASH(aa 51-200).Subsequent research shows that overexpression of FLASH in cells enhances global SUMO1 conjugation and p53-SUMO1 conjugation,therefore providing a plausible explanation for the underlying mechanism of FLASH enhancing the transcriptional activity of p53.Since promyelocytic leukemia protein nuclear body(PML NB)serves as subcellular reactors for SUMO conjugation within the cell,and the PML Ⅳ isoform can specifically enhance the SUMO modifica-tion of p53,we have investigated the interaction between FLASH and PML Ⅳ,and elucidated the struc-tural basis of their interaction:both FLASH-N3A(501-802)and FLASH-C2(1 807-1 981)bind to PML Ⅳ(aa 228-633).Further investigations reveal that they can synergistically enhance global SUMO1 modification as well as SUMO1 modification of p53.The interaction between FLASH and tumor suppres-sors p53 or PML Ⅳ enriches our understanding of its function and reveals the potential mechanism of FLASH in tumor development,therefore offering novel insights into cancer diagnosis and treatment.

BACKGROUND:In recent years,some scholars in the field of tendon bone injury have attached stromal cell-derived factor 1 to tissue engineering scaffolds to promote tendon bone healing,and achieved good results.However,whether stromal cell-derived factor 1 promotes tendon bone healing mechanisms and participates in the repair of natural healing has not yet been defined. OBJECTIVE:To study the expression of stroma-cell derived factor 1 during tendon bone healing after rupture of the whole supraspinatus muscle of the rabbit rotator cuff and its migration effect and optimal in vitro migration promoting concentration on stem cells during tendon bone injury. METHODS:Totally 18 adult New Zealand rabbits were randomly selected to establish rotator cuff injury models,and an additional 3 rabbits were selected as blank controls.At 3,5,7,14,21,and 28 days after modeling,three rabbits were executed separately and the rabbits in the blank group were sacrificed.The tissues of tendon bone junction were taken and stored in a-80℃refrigerator.The expression of stromal cell-derived factor 1 was detected by ELISA at each time point after injury.Mesenchymal stem cells were isolated from the bone marrow of young rabbit femur,cultured,and identified.Transwell assay was performed to verify the migration-promoting effect of stromal cell-derived factor 1 on stem cells and the optimal migration-promoting concentration in vitro.The stem cells cultured to P3 were co-cultured with BrdU and injected into the rabbit ear marginal vein,and immunohistochemical staining was used to verify whether the stem cells migrated to the injury site. RESULTS AND CONCLUSION:(1)Stromal cell-derived factor 1 gene expression was bimodal during rotator cuff tendon bone healing.Stromal cell-derived factor 1 gene expression increased significantly at 3 days post-injury(P<0.01)and then decreased,reaching a minimum at 5 days post-injury.It increased again and reached a peak 14 days after injury(P<0.01)and then decreased.(2)Cell immunohistochemical staining displayed that stem cells labeled with BrdU did migrate to the injury site.(3)The results of the transwell experiment exhibited that 60-80 ng/mL stromal cell-derived factor 1 had the best effect on promoting migration of stem cells,while a concentration of 200 ng/mL inhibited migration.(4)Stromal cell-derived factor 1 is involved in the healing of rotator cuff tendon bone during the inflammatory response phase and the proliferation phase.The mechanism of action may be to promote the migration of stem cells to the injury and their differentiation into various types of cells to promote repair.In addition,the pro-migration effect of stromal cell-derived factor 1 exists at a range of concentrations,beyond which it may act as an inhibitor.

Objective:To investigate the efficacy and side effects of concurrent chemoradiotherapy with or without nimotuzumab in the treatment of locally advanced nasopharyngeal carcinoma after neoadjuvant chemotherapy.Methods:In the prospective study, 100 patients with stage Ⅲ-Ⅳa locally advanced nasopharyngeal carcinoma (except T 3N 0M 0 stage) who met the inclusion criteria were randomly divided into the experimental and control groups using the random number table method. Patients in both groups were treated with neoadjuvant chemotherapy using TPF (paclitaxel liposome, cisplatin, and 5-fluorouracil) regimen for 2 cycles. At 2 weeks after chemotherapy, concurrent chemoradiotherapy plus nimotuzumab targeted therapy was given in the experimental group, and concurrent chemoradiotherapy was delivered in the control group. The main observation index was the distant metastasis-free survival (DMFS) rate. Log-rank test and multivariate Cox regression analysis were used. Results:The objective remission rate and complete remission rate in the experimental and control groups were 100% vs. 98% ( P=1.000) and 92.0% vs. 80% ( P=0.084). The 3-year DMFS in the experimental and control groups were 91.4 % vs. 76.1 % ( P=0.043). The 3-year progression-free survival (PFS), locoregional recurrence-free survival (LRFS) and overall survival (OS) in two groups were 87.3 % vs. 74.1 % ( P=0.097), 94.5 % vs. 85.6 % ( P=0.227) and 90.5% vs. 85.2% ( P=0.444). Subgroup analysis showed that patients with age<60 years ( HR=0.34, 95% CI=0.12-0.94, P=0.037), neutrophil-to-lymphocyte ratio (NLR)≤4 ( HR=0.34, 95% CI=0.13-0.89, P=0.028) received concurrent chemoradiotherapy plus nimotuzumab obtained better PFS. Multivariate analysis showed that NLR was an independent risk factor for disease progression ( HR=5.94, 95% CI=1.18-29.81, P=0.030) and distant metastasis ( HR=13.76, 95% CI=1.52-124.36, P=0.020). Conclusions:Compared with concurrent chemoradiotherapy alone, concurrent chemoradiotherapy combined with nimotuzumab after neoadjuvant chemotherapy can significantly increase DMFS rate for patients with locally advanced nasopharyngeal carcinoma. The incidence of side effects is similar in two groups. Concurrent chemoradiotherapy plus nimotuzumab after neoadjuvant chemotherapy may be a preferred treatment strategy for locally advanced nasopharyngeal carcinoma.

Objective:To evaluate the safety and efficiency of China-made Toumai Robot-assisted laparoscopic radical prosta-tectomy(LRP).Methods:This study included 40 cases of PCa treated from January 2023 to May 2023 by robot-assisted LRP with preservation of the bladder neck and maximal functional urethral length,15 cases with the assistance of Toumai Robot(the TMR group)and the other 25 with the assistance of da Vinci Robot as controls(the DVR group).We recorded the docking time,laparo-scopic surgery time,vesico-urethral anastomosis time,intraoperative blood loss and postoperative urinary continence,and compared them between the two groups.Results:Operations were successfully completed in all the cases.No statistically significant differ-ences were observed between the TMR and DVR groups in the docking time(6 min vs 5 min,P＞0.05)or intraoperative blood loss(200 ml vs 150 ml,P＞0.05).The TMR group,compared with the DVR group,showed a significantly longer median laparoscopic surgery time(146 min vs 130 min,P＜0.05)and median vesico-urethral anastomosis time(19 min vs 16 min,P＜0.05).There were no statistically significant differences between the TMR and DVR groups in the rates of urinary continence recovery immediately af-ter surgery(60.0％[9/15]vs 64.0％[16/25],P＞0.05)or at 1 month(80.0％[12/15])vs(76.0％[19/25],P＞0.05),3 months(93.3％[14/15])vs(92.0％[23/25],P＞0.05)and 6 months postoperatively(100％[15/15])vs(96％[24/25],P＞0.05).Conclusion:China-made Toumai? Robot surgical system is safe and reliable for laparoscopic radical prosta-tectomy,with satisfactory postoperative recovery of urinary continence.