Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 139
Filter
1.
Rev Med Virol ; 33(6): e2476, 2023 11.
Article in English | MEDLINE | ID: mdl-37578892

ABSTRACT

This study aimed to clarify the beneficial effect and the clinical application value of Paxlovid in the treatment of coronavirus disease-19 (COVID-19) through a systematic review. Databases including PubMed, Cochrane Library, Chinese Clinical Trial Registry, and ClinicalTrials.gov were systematically searched for interventional or observational studies on the efficacy and safety of Paxlovid in the treatment of SARS-COV-2. The relative and absolute effect sizes for the outcomes were calculated based on the data reported in the original intervention literature. The external applicability of the evidence was analysed in terms of clinical application scenarios, patient willingness, and cost utility. One interventional and three observational studies were conducted. Four studies published in 2022, had participation sample sizes ranging 1780-109,254. Based on the randomised controlled trial data, the risk of all-cause mortality, all-cause death, and hospitalisation was significantly reduced in the Paxlovid group. Serious adverse events were reduced during the study. Based on observational studies, Paxlovid can significantly reduce the risk of death and hospitalisation in older patients with COVID-19 (moderate certainty) and improve in-hospital disease progression, composite disease progression, and viral load (low certainty). Paxlovid did not improve the outcomes of death and hospitalisation (low certainty) in patients aged <65 years. As per the economic utility analysis, the economic cost of reducing one death dramatically decreased with increasing age. Early use of Paxlovid in the older adult population with COVID-19 is beneficial. However, in the setting of limited resources, Paxlovid should be prioritised for older patients.


Subject(s)
COVID-19 , Humans , Aged , SARS-CoV-2 , Reproducibility of Results , Disease Progression
2.
Acta Pharmacol Sin ; 2024 Apr 12.
Article in English | MEDLINE | ID: mdl-38609561

ABSTRACT

Proteolysis targeting chimeras (PROTACs) have emerged as revolutionary anticancer therapeutics that degrade disease-causing proteins. However, the anticancer performance of PROTACs is often impaired by their insufficient bioavailability, unsatisfactory tumor specificity and ability to induce acquired drug resistance. Herein, we propose a polymer-conjugated PROTAC prodrug platform for the tumor-targeted delivery of the most prevalent von Hippel-Lindau (VHL)- and cereblon (CRBN)-based PROTACs, as well as for the precise codelivery of a degrader and conventional small-molecule drugs. The self-assembling PROTAC prodrug nanoparticles (NPs) can specifically target and be activated inside tumor cells to release the free PROTAC for precise protein degradation. The PROTAC prodrug NPs caused more efficient regression of MDA-MB-231 breast tumors in a mouse model by degrading bromodomain-containing protein 4 (BRD4) or cyclin-dependent kinase 9 (CDK9) with decreased systemic toxicity. In addition, we demonstrated that the PROTAC prodrug NPs can serve as a versatile platform for the codelivery of a PROTAC and chemotherapeutics for enhanced anticancer efficiency and combination benefits. This study paves the way for utilizing tumor-targeted protein degradation for precise anticancer therapy and the effective combination treatment of complex diseases.

3.
Acta Pharmacol Sin ; 41(9): 1246-1254, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32210356

ABSTRACT

Mitophagy is a degradative pathway that mediates the degradation of the entire mitochondria, and defects in this process are implicated in many diseases including cancer. In mammals, mitophagy is mediated by BNIP3L (also known as NIX) that is a dual regulator of mitochondrial turnover and programmed cell death pathways. Acute myeloid leukemia (AML) cells with deficiency of BNIP3L are more sensitive to mitochondria-targeting drugs. But small molecular inhibitors for BNIP3L are currently not available. Some immunomodulatory drugs (IMiDs) have been proved by FDA for hematologic malignancies, however, the underlining molecular mechanisms are still elusive, which hindered the applications of BNIP3L inhibition for AML treatment. In this study we carried out MS-based quantitative proteomics analysis to identify the potential neosubstrates of a novel thalidomide derivative CC-885 in A549 cells. In total, we quantified 5029 proteins with 36 downregulated in CRBN+/+ cell after CC-885 administration. Bioinformatic analysis showed that macromitophagy pathway was enriched in the negative pathway after CC-885 treatment. We further found that CC-885 caused both dose- and time-dependent degradation of BNIP3L in CRBN+/+, but not CRBN-/- cell. Thus, our data uncover a novel role of CC-885 in the regulation of mitophagy by targeting BNIP3L for CRL4CRBN E3 ligase-dependent ubiquitination and degradation, suggesting that CC-885 could be used as a selective BNIP3L degradator for the further investigation. Furthermore, we demonstrated that CC-885 could enhance AML cell sensitivity to the mitochondria-targeting drug rotenone, suggesting that combining CC-885 and mitochondria-targeting drugs may be a therapeutic strategy for AML patients.


Subject(s)
Adaptor Proteins, Signal Transducing/metabolism , Membrane Proteins/metabolism , Mitophagy/drug effects , Phenylurea Compounds/pharmacology , Proto-Oncogene Proteins/metabolism , Thalidomide/analogs & derivatives , Tumor Suppressor Proteins/metabolism , Ubiquitin-Protein Ligases/metabolism , Cell Line, Tumor , Drug Synergism , HEK293 Cells , Humans , Proteasome Endopeptidase Complex/metabolism , Proteolysis/drug effects , Rotenone/pharmacology , Thalidomide/pharmacology , Ubiquitination/drug effects
4.
Angew Chem Int Ed Engl ; 58(35): 12190-12194, 2019 Aug 26.
Article in English | MEDLINE | ID: mdl-31250946

ABSTRACT

Highly enantioselective [3+3] and [3+4] annulations of isatin-derived enals with ethynylethylene carbonates and ethynyl benzoxazinanones are enabled by NHC/cooper cooperative catalysis, leading to a big library of spirooxindole derivatives in high structural diversity and enantioselectivity (up to 99 % ee). Both reactions represent a nicely synergistic integration of NHC and copper catalysis, in which both catalysts activate the substrates and the chiral NHC perfectly controls the stereochemistry.

5.
Med Sci Monit ; 23: 5202-5210, 2017 Nov 01.
Article in English | MEDLINE | ID: mdl-29089476

ABSTRACT

BACKGROUND Chronic hepatitis B virus (HBV) infection is the major cause of hepatocellular carcinoma (HCC). HBV X protein (HBx) plays a crucial role in the development of HCC. Moreover, many tripartite motif (TRIM) family proteins exert diverse biological functions in hepatocarcinogenesis. However, as a novel member of this family, the specific effect of TRIM52 is still largely obscure. In the present study, we investigated the expression and function of TRIM52 in HBV-associated HCC. MATERIAL AND METHODS Fluorescence quantitative polymerase chain reaction (FQ-PCR) was performed to detect the HBV DNA levels in the peripheral blood of HCC patients. Quantitative real-time PCR (qRT-PCR) and Western blot analysis were performed to detect the expression of TRIM52, HBx, and NF-κB p65. HBx-pcDNA3.1 and TRIM52-shRNA were used to induce HBx ectopic expression and TRIM52 silencing, respectively. Pyrrolidine dithiocarbamate (PDTC) was used to block the activation of NF-κB. Cell proliferation was detected using the Cell Counting Kit-8 (CCK-8) assay. RESULTS TRIM52 expression was up-regulated together with HBx in HBV-associated HCC tissues. Ectopic expression of HBx elevated TRIM52 expression in HepG2 cells. TRIM52 silencing repressed the proliferation of HepG2.2.15 cells. Moreover, NF-κB p65 expression was increased in HCC cell lines. Blocking NF-κB activation with PDTC suppressed TRIM52 expression and attenuated the viability of HepG2.2.15 cells. CONCLUSIONS These findings indicate that TRIM52 can promote cell proliferation and HBx may regulate TRIM52 expression via the NF-κB signaling pathway in HBV-associated HCC.


Subject(s)
Carcinoma, Hepatocellular/metabolism , Carcinoma, Hepatocellular/virology , Hepatitis B virus/physiology , Liver Neoplasms/metabolism , Liver Neoplasms/virology , Tripartite Motif Proteins/metabolism , Carcinoma, Hepatocellular/pathology , Cell Proliferation , DNA, Viral/metabolism , Gene Expression Regulation, Neoplastic , Gene Silencing , Hep G2 Cells , Humans , Liver Neoplasms/pathology , Trans-Activators/metabolism , Transcription Factor RelA/metabolism , Up-Regulation/genetics , Viral Regulatory and Accessory Proteins
6.
Microbiology (Reading) ; 161(Pt 1): 131-147, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25355936

ABSTRACT

Proteins secreted by Bacillus amyloliquefaciens FZB42, a root-associated plant growth-promoting rhizobacterium, are thought to play an important role in the establishment of beneficial interactions with plants. To investigate the possible role of proteins in this process, extracellular proteome maps of B. amyloliquefaciens FZB42 during the late exponential and stationary growth phases were generated using 2D gel electrophoresis. Out of the 121 proteins identified by MALDI-TOF MS, 61 were predicted to contain secretion signals. A few of the others, bearing no signal peptide, have been described as elicitors of plant innate immunity, including flagellin proteins, cold-shock proteins and the elongation factor Tu, suggesting that B. amyloliquefaciens FZB42 protects plants against disease by eliciting innate immunity. Our reference maps were used to monitor bacterial responses to maize root exudates. Approximately 34 proteins were differentially secreted in response to root exudates during either the late exponential or stationary phase. These were mainly involved in nutrient utilization and transport. The protein with the highest fold change in the presence of maize root exudates during the late exponential growth phase was acetolactate synthase (AlsS), an enzyme involved in the synthesis of the volatile acetoin, known as an inducer of systemic resistance against plant pathogens and as a trigger of plant growth.


Subject(s)
Bacillus/metabolism , Bacterial Proteins/metabolism , Plant Exudates/metabolism , Plant Roots/metabolism , Plant Roots/microbiology , Proteome , Proteomics , Amino Acids/metabolism , Bacillus/genetics , Bacillus/growth & development , Carbohydrate Metabolism , Carbohydrates , Extracellular Space , Gene Expression Profiling , Hydrolysis , Iron/metabolism , Phosphorus/metabolism , Proteomics/methods , Symbiosis
7.
Appl Environ Microbiol ; 81(6): 2006-14, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25576604

ABSTRACT

Xylanases are crucial for lignocellulosic biomass deconstruction and generally contain noncatalytic carbohydrate-binding modules (CBMs) accessing recalcitrant polymers. Understanding how multimodular enzymes assemble can benefit protein engineering by aiming at accommodating various environmental conditions. Two multimodular xylanases, XynA and XynB, which belong to glycoside hydrolase families 11 (GH11) and GH10, respectively, have been identified from Caldicellulosiruptor sp. strain F32. In this study, both xylanases and their truncated mutants were overexpressed in Escherichia coli, purified, and characterized. GH11 XynATM1 lacking CBM exhibited a considerable improvement in specific activity (215.8 U nmol(-1) versus 94.7 U nmol(-1)) and thermal stability (half-life of 48 h versus 5.5 h at 75°C) compared with those of XynA. However, GH10 XynB showed higher enzyme activity and thermostability than its truncated mutant without CBM. Site-directed mutagenesis of N-terminal amino acids resulted in a mutant, XynATM1-M, with 50% residual activity improvement at 75°C for 48 h, revealing that the disordered region influenced protein thermostability negatively. The thermal stability of both xylanases and their truncated mutants were consistent with their melting temperature (Tm), which was determined by using differential scanning calorimetry. Through homology modeling and cross-linking analysis, we demonstrated that for XynB, the resistance against thermoinactivation generally was enhanced through improving both domain properties and interdomain interactions, whereas for XynA, no interdomain interactions were observed. Optimized intramolecular interactions can accelerate thermostability, which provided microbes a powerful evolutionary strategy to assemble catalysts that are adapted to various ecological conditions.


Subject(s)
Carbohydrate Metabolism , Firmicutes/enzymology , Glycoside Hydrolases/metabolism , Calorimetry , Cloning, Molecular , DNA Mutational Analysis , Enzyme Stability , Escherichia coli/genetics , Escherichia coli/metabolism , Gene Expression , Glycoside Hydrolases/chemistry , Glycoside Hydrolases/genetics , Kinetics , Models, Molecular , Mutagenesis, Site-Directed , Protein Binding , Recombinant Proteins/chemistry , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Temperature , Transition Temperature
8.
Article in English | MEDLINE | ID: mdl-24964672

ABSTRACT

Round pneumonia is an uncommon form of pulmonary infection usually found in children. It may resemble pulmonary neoplasm on radiographs. We present a case of round pneumonia in a 43-year-old male with a history of smoking and a family history of lung cancer. The patient was treated with antibiotics for more than two weeks, after which the infection resolved completely both clinically and radiologically. Clinicians should consider this uncommon type of pneumonia in the differential diagnosis of spherical pulmonary masses to avoid unnecessary diagnostic tests.


Subject(s)
Community-Acquired Infections/diagnosis , Pneumonia/diagnosis , Adult , Anti-Bacterial Agents/therapeutic use , Community-Acquired Infections/drug therapy , Diagnosis, Differential , Humans , Lung Neoplasms/diagnosis , Male , Pneumonia/drug therapy , Radiography, Thoracic , Smoking/adverse effects , Tomography, X-Ray Computed
9.
Adv Sci (Weinh) ; 11(26): e2400594, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38689503

ABSTRACT

Proteolysis targeting chimeras (PROTACs) have emerged as a promising strategy for drug discovery and exploring protein functions, offering a revolutionary therapeutic modality. Currently, the predominant approach to PROTACs discovery mainly relies on an empirical design-synthesis-evaluation process involving numerous cycles of labor-intensive synthesis-purification and bioassay data collection. Therefore, the development of innovative methods to expedite PROTAC synthesis and exploration of chemical space remains highly desired. Here, a direct-to-biology strategy is reported to streamline the synthesis of PROTAC libraries on plates, enabling the seamless transfer of reaction products to cell-based bioassays without the need for additional purification. By integrating amide coupling and light-induced primary amines and o-nitrobenzyl alcohols cyclization (PANAC) photoclick chemistry into a plate-based synthetic process, this strategy produces PROTAC libraries with high efficiency and structural diversity. Moreover, by employing this platform for PROTACs screening, we smoothly found potent PROTACs effectively inhibit triple-negative breast cancer (TNBC) cell growth and induce rapid, selective targeted degradation of cyclin-dependent kinase 9 (CDK9). The study introduces a versatile platform for assembling PROTACs on plates, followed by direct biological evaluation. This approach provides a promising opportunity for high-throughput synthesis of PROTAC libraries, thereby enhancing the efficiency of exploring chemical space and accelerating the discovery of PROTACs.


Subject(s)
Drug Discovery , Proteolysis , Humans , Drug Discovery/methods , Proteolysis/drug effects , Cell Line, Tumor , Triple Negative Breast Neoplasms/drug therapy , Proteolysis Targeting Chimera
10.
BMJ Open ; 14(6): e079212, 2024 Jun 10.
Article in English | MEDLINE | ID: mdl-38858161

ABSTRACT

INTRODUCTION: Severe septic cardiomyopathy (SCM) is one of the main causes of refractory septic shock (RSS), with a high mortality. The application of venoarterial extracorporeal membrane oxygenation (ECMO) to support the impaired cardiac function in patients with septic shock remains controversial. Moreover, no prospective studies have been taken to address whether venoarterial ECMO treatment could improve the outcome of patients with sepsis-induced cardiogenic shock. The objective of this study is to assess whether venoarterial ECMO treatment can improve the 30-day survival rate of patients with sepsis-induced refractory cardiogenic shock. METHODS AND ANALYSIS: ExtraCorporeal Membrane Oxygenation in the therapy for REfractory Septic shock with Cardiac function Under Estimated is a prospective, multicentre, non-randomised, cohort study on the application of ECMO in SCM. At least 64 patients with SCM and RSS will be enrolled in an estimated ratio of 1:1.5. Participants taking venoarterial ECMO during the period of study are referred to as cohort 1, and patients receiving only conventional therapy without ECMO belong to cohort 2. The primary outcome is survival in a 30-day follow-up period. Other end points include survival to intensive care unit (ICU) discharge, hospital survival, 6-month survival, quality of life for long-term survival (EQ-5D score), successful rate of ECMO weaning, long-term survivors' cardiac function, the number of days alive without continuous renal replacement therapy, mechanical ventilation and vasopressor, ICU and hospital length of stay, the rate of complications potentially related to ECMO treatment. ETHICS AND DISSEMINATION: The trial has been approved by the Clinical Research and Application Institutional Review Board of the Second Affiliated Hospital of Guangzhou Medical University (2020-hs-51). Participants will be screened and enrolled from ICU patients with septic shock by clinicians, with no public advertisement for recruitment. Results will be disseminated in research journals and through conference presentations. TRIAL REGISTRATION NUMBER: NCT05184296.


Subject(s)
Extracorporeal Membrane Oxygenation , Shock, Cardiogenic , Shock, Septic , Extracorporeal Membrane Oxygenation/methods , Humans , Shock, Septic/therapy , Shock, Septic/mortality , Shock, Septic/complications , Prospective Studies , Shock, Cardiogenic/therapy , Shock, Cardiogenic/mortality , Cardiomyopathies/therapy , Multicenter Studies as Topic , Male , Intensive Care Units , Female , Adult , Survival Rate
11.
J Med Chem ; 67(12): 10035-10056, 2024 Jun 27.
Article in English | MEDLINE | ID: mdl-38885173

ABSTRACT

Triple-negative breast cancer (TNBC) represents a highly aggressive and heterogeneous malignancy. Currently, effective therapies for TNBC are very limited and remain a significant unmet clinical need. Targeting the transcription-regulating cyclin-dependent kinase 9 (CDK9) has emerged as a promising avenue for therapeutic treatment of TNBC. Herein, we report the design, synthesis, optimization, and evaluation of a new series of aminopyrazolotriazine compounds as orally bioavailable, potent, and CDK9/2 selectivity-improved inhibitors, enabling efficacious inhibition of TNBC cell growth, as well as notable antitumor effect in TNBC models. The compound C35 demonstrated low-nanomolar potency with substantially improved CDK9/2 selectivity, downregulated the CDK9-downstream targets (e.g., MCL-1), and induced apoptosis in TNBC cell lines. Moreover, with the desired oral bioavailability, oral administration of C35 could significantly suppress the tumor progression in two TNBC mouse models. This study demonstrates that target transcriptional regulation is an effective strategy and holds promising potential as a targeted therapy for the treatment of TNBC.


Subject(s)
Antineoplastic Agents , Cyclin-Dependent Kinase 9 , Protein Kinase Inhibitors , Triple Negative Breast Neoplasms , Cyclin-Dependent Kinase 9/antagonists & inhibitors , Cyclin-Dependent Kinase 9/metabolism , Triple Negative Breast Neoplasms/drug therapy , Triple Negative Breast Neoplasms/pathology , Humans , Animals , Female , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use , Antineoplastic Agents/pharmacokinetics , Antineoplastic Agents/chemistry , Antineoplastic Agents/chemical synthesis , Administration, Oral , Protein Kinase Inhibitors/pharmacology , Protein Kinase Inhibitors/therapeutic use , Protein Kinase Inhibitors/pharmacokinetics , Protein Kinase Inhibitors/chemistry , Protein Kinase Inhibitors/chemical synthesis , Mice , Cell Line, Tumor , Structure-Activity Relationship , Biological Availability , Cell Proliferation/drug effects , Apoptosis/drug effects , Drug Discovery , Transcription, Genetic/drug effects , Mice, Nude , Xenograft Model Antitumor Assays
12.
Nat Commun ; 15(1): 1465, 2024 Feb 17.
Article in English | MEDLINE | ID: mdl-38368419

ABSTRACT

Protein-modifying enzymes regulate the dynamics of myriad post-translational modification (PTM) substrates. Precise characterization of enzyme-substrate associations is essential for the molecular basis of cellular function and phenotype. Methods for direct capturing global substrates of protein-modifying enzymes in living cells are with many challenges, and yet largely unexplored. Here, we report a strategy to directly capture substrates of lysine-modifying enzymes via PTM-acceptor residue crosslinking in living cells, enabling global profiling of substrates of PTM-enzymes and validation of PTM-sites in a straightforward manner. By integrating enzymatic PTM-mechanisms, and genetically encoding residue-selective photo-crosslinker into PTM-enzymes, our strategy expands the substrate profiles of both bacterial and mammalian lysine acylation enzymes, including bacterial lysine acylases PatZ, YiaC, LplA, TmcA, and YjaB, as well as mammalian acyltransferases GCN5 and Tip60, leading to discovery of distinct yet functionally important substrates and acylation sites. The concept of direct capturing substrates of PTM-enzymes via residue crosslinking may extend to the other types of amino acid residues beyond lysine, which has the potential to facilitate the investigation of diverse types of PTMs and substrate-enzyme interactive proteomics.


Subject(s)
Lysine , Proteins , Animals , Lysine/metabolism , Proteins/metabolism , Acylation , Proteomics/methods , Protein Processing, Post-Translational , Mammals/metabolism
13.
Cancer Immunol Immunother ; 62(2): 393-403, 2013 Feb.
Article in English | MEDLINE | ID: mdl-22926105

ABSTRACT

Peptide vaccine based on tumor-associated antigen (TAA), which usually belongs to self-antigen with poor immunogenicity, has been considered as an attractive option for treatment of malignant tumors. The ideal TAA epitopes should have stable affinity to major histocompatibility complex (MHC) molecules and elicit strong anti-tumor immune response. Although point-mutation technology of TAA peptide may increase the binding capability to MHC molecules, some previous studies have revealed that part of the variant peptides results in lymphocyte not to effectively cross-recognize and kill the target tumor expressed wild-type TAA. Here, we designed a novel HLA-A2-restricted mutated TAA Survivin epitope nonapeptide Sur79L2 (KLSSGCAFL) that showed higher binding ability compared to wild-type peptide Sur79 (KHSSGCAFL) in T2-binding assays. To investigate whether Sur79L2 can induce Survivin-specific anti-hepatocellular carcinoma (HCC) response, we stimulated tumor-associated lymphocytes from a HCC patient with Sur79L2 in vitro. IFN-γ release and cytotoxicity assays showed Sur79L2 could effectively cross-recognize and lysis T2 cell plus peptide Sur79 and HCC cell lines (expression of wild-type Survivin antigen) in an HLA-A2-restricted manner. In contrast, peptide Sur95 (ELTLGEFLKL) that has been reported as a very promising anti-tumor epitope in a variety of tumors except HCC were not able to generate detectable cytotoxic immune responses against HCC in this study. Our results suggest that point-mutated peptide Sur79L2 is a new HLA-A2-restricted CTL epitope and may be useful for the immunotherapy for patients with HCC.


Subject(s)
Antigens, Neoplasm/drug effects , Carcinoma, Hepatocellular/drug therapy , Epitopes/immunology , HLA-A2 Antigen/immunology , Inhibitor of Apoptosis Proteins/genetics , Liver Neoplasms/drug therapy , Oligopeptides/pharmacology , T-Lymphocytes, Cytotoxic/drug effects , Antigens, Neoplasm/immunology , Carcinoma, Hepatocellular/immunology , Cell Line, Tumor , Cells, Cultured , Epitopes/genetics , Humans , Inhibitor of Apoptosis Proteins/analysis , Inhibitor of Apoptosis Proteins/immunology , Interferon-gamma/metabolism , Liver Neoplasms/immunology , Male , Middle Aged , Mutation , Oligopeptides/immunology , Survivin , T-Lymphocytes, Cytotoxic/immunology
14.
BMC Microbiol ; 13: 137, 2013 Jun 18.
Article in English | MEDLINE | ID: mdl-23773687

ABSTRACT

BACKGROUND: Nine gene clusters dedicated to nonribosomal synthesis of secondary metabolites with possible antimicrobial action, including polymyxin and fusaricidin, were detected within the whole genome sequence of the plant growth-promoting rhizobacterium (PGPR) Paenibacillus polymyxa M-1. To survey the antimicrobial compounds expressed by M-1 we analyzed the active principle suppressing phytopathogenic Erwinia spp. RESULTS: P. polymyxa M-1 suppressed the growth of phytopathogenic Erwinia amylovora Ea 273, and E. carotovora, the causative agents of fire blight and soft rot, respectively. By MALDI-TOF mass spectrometry and reversed-phase high-performance liquid chromatography (RP-HPLC), two antibacterial compounds bearing molecular masses of 1190.9 Da and 1176.9 Da were detected as being the two components of polymyxin P, polymyxin P1 and P2, respectively. The active principle acting against the two Erwinia strains was isolated from TLC plates and identified by postsource decay (PSD)-MALDI-TOF mass spectrometry as polymyxin P1 and polymyxin P2. These findings were corroborated by domain structure analysis of the polymyxin (pmx) gene cluster detected in the M-1 chromosome which revealed that corresponding to the chemical structure of polymyxin P, the gene cluster is encoding D-Phe in position 6 and L-Thr in position 7. CONCLUSIONS: Identical morphological changes in the cell wall of the bacterial phytopathogens treated with either crude polymyxin P or culture supernatant of M-1 corroborated that polymyxin P is the main component of the biocontrol effect exerted by strain M-1 against phytopathogenic Erwinia spp.


Subject(s)
Anti-Bacterial Agents/pharmacology , Erwinia/drug effects , Paenibacillus/chemistry , Polymyxins/pharmacology , Biological Control Agents , Cell Wall/ultrastructure , Erwinia/cytology , Multigene Family , Paenibacillus/genetics
15.
Acta Crystallogr C ; 69(Pt 11): 1373-7, 2013 Nov.
Article in English | MEDLINE | ID: mdl-24192192

ABSTRACT

In the Cu(II) compound catena-poly[[copper(II)-µ-[2-({2-[2-(naphthalen-2-yloxy)-1-oxidoethylidene]hydrazin-1-ylidene}methyl)phenolato]] dimethylformamide monosolvate monohydrate], {[Cu(C19H14N2O3)]·C3H7NO·H2O}n, (I), the Cu(II) cation is O,N,O'-chelated by one ligand and further N,O-chelated by a second ligand, and exhibits a distorted square-pyramidal coordination environment. The ligand acts as an overall pentadentate bridge between two metal ions, thus forming a novel coordination polymer. In the trinuclear Ni(II) compound diaquabis(1H-imidazole)bis[µ-2-oxido-N'-(1-oxido-2-phenoxyethylidene)benzohydrazidato]trinickel(II) dimethylformamide tetrasolvate, [Ni3(C15H11N2O4)2(C3H4N2)2(H2O)2]·4C3H7NO, (II), the three Ni(II) cations are directly linked by two trans diazine (N-N) bridges and are strictly collinear by symmetry. The central Ni(II) cation, located on an inversion centre, is coordinated by two water O atoms and is further N,O-chelated by two 2-oxido-N'-(1-oxido-2-phenoxyethylidene)benzohydrazidate(3-) ligands in an elongated octahedral coordination geometry. The two terminal centrosymmetrically related Ni(II) cations are coordinated by an imidazole ligand and O,N,O'-chelated by a hydrazidate ligand in a distorted square-planar coordination geometry. Hydrogen bonds link individual molecules of (II) into a chain along [100].


Subject(s)
Chelating Agents/chemistry , Coordination Complexes/chemistry , Copper/chemistry , Nickel/chemistry , Crystallography, X-Ray , Hydrogen Bonding , Ligands , Molecular Structure
16.
Methods Mol Biol ; 2676: 131-146, 2023.
Article in English | MEDLINE | ID: mdl-37277629

ABSTRACT

Posttranslational modifications (PTMs) of lysine residues are major regulators of gene expression, protein-protein interactions, and protein localization and degradation. Histone lysine benzoylation is a recently identified epigenetic marker associated with active transcription, which has physiological relevance distinct from histone acetylation and can be regulated by debenzoylation of sirtuin 2 (SIRT2). Herein, we provide a protocol for the incorporation of benzoyllysine and fluorinated benzoyllysine into full-length histone proteins, which further serve as benzoylated histone probes with NMR or fluorescence signal for investigating the dynamics of SIRT2-mediated debenzoylation.


Subject(s)
Amino Acids , Lysine , Lysine/metabolism , Amino Acids/metabolism , Histones/metabolism , Sirtuin 2/genetics , Protein Processing, Post-Translational , Acetylation
17.
World J Psychiatry ; 13(8): 533-542, 2023 Aug 19.
Article in English | MEDLINE | ID: mdl-37701542

ABSTRACT

BACKGROUND: As the perioperative risk of elderly patients with extremely unstable hip fractures (EUHFs) is relatively high and therapeutic effect is not satisfactory, new thera-peutic strategies need to be proposed urgently to improve the efficacy and clinical outcomes of such patients. AIM: To determine the influence of two surgical treatment modalities on postoperative cognitive function (CF) and delirium in elderly patients with EUHFs. METHODS: A total of 60 elderly patients consecutively diagnosed with EUHF between September 2020 and January 2022 in the Chongqing University Three Gorges Hospital were included. Of them, 30 patients received conventional treatment (control group; general consultation + fracture type-guided internal fixation), and the other 30 received novel treatment (research group; perioperative multidisciplinary treatment diagnosis and treatment + individualized surgical plan + risk prediction). Information on hip function [Harris hip score (HHS)], perioperative risk of orthopedic surgery [Physiological and Operative Severity Score for the Enumeration of Mortality and Morbidity (POSSUM)], CF [Montreal cognitive assessment scale (MoCA)], postoperative delirium [mini-cognitive (Mini-Cog)], adverse events (AEs; internal fixation failure, infection, nonunion, malunion, and postoperative delirium), and clinical indicators [operation time (OT), postoperative hospital length of stay (HLOS), ambulation time, and intraoperative blood loss (IBL)] were collected from both groups for comparative analyses. RESULTS: The HHS scores were similar between both groups. The POSSUM score at 6 mo after surgery was significantly lower in the research group compared with the control group, and MoCA and Mini-Cog scores were statistically higher. In addition, the overall postoperative complication rate was significantly lower in the research than in the control group, including reduced OT, postoperative HLOS, ambulation time, and IBL. CONCLUSION: The new treatment modality has more clinical advantages over the conventional treatment, such as less IBL, faster functional recovery, more effectively optimized perioperative quality control, improved postoperative CF, mitigated postoperative delirium, and reduced operation-related AEs.

18.
Front Genet ; 14: 1241834, 2023.
Article in English | MEDLINE | ID: mdl-38239853

ABSTRACT

Background: Cholangiocarcinoma is characterized by significant cellular heterogeneity and complex intercellular communication, which contribute to its progression and therapeutic resistance. Therefore, unraveling this complexity is essential for the development of effective treatments. Methods: We employed single-cell RNA sequencing (scRNA-seq) to investigate cellular heterogeneity and intercellular communication in cholangiocarcinoma and adjacent normal tissues from two patients. Distinct cell types were identified, and gene ontology analyses were conducted to determine enriched pathways. Moreover, cell-cell communications were analyzed using CellChat, a computational framework. Additionally, we performed sub-clustering analysis of T cells and fibroblasts. Results: The scRNA-seq analysis revealed distinct cell clusters and diverse cellular compositions of cholangiocarcinoma. CellChat analysis underscored an amplified outgoing signal from fibroblasts within the tumor, suggesting their pivotal role in the tumor microenvironment. Furthermore, T cell sub-clustering analysis revealed an active immune response within the tumor and new tumor-specific T cell clonotypes, suggesting scope for targeted immunotherapies. Moreover, fibroblast sub-clustering analysis indicated distinct functional states and highlighted the role of activated fibroblasts in shaping intercellular communication, particularly via CD99 and FN1 signaling. Conclusion: Our findings reveal the intricate cellular heterogeneity and dynamic intercellular communication in cholangiocarcinoma, providing valuable insights into disease progression and potential therapeutic strategies.

19.
Nat Chem ; 15(6): 803-814, 2023 06.
Article in English | MEDLINE | ID: mdl-37106095

ABSTRACT

Precise dissection of DNA-protein interactions is essential for elucidating the recognition basis, dynamics and gene regulation mechanism. However, global profiling of weak and dynamic DNA-protein interactions remains a long-standing challenge. Here, we establish the light-induced lysine (K) enabled crosslinking (LIKE-XL) strategy for spatiotemporal and global profiling of DNA-protein interactions. Harnessing unique abilities to capture weak and transient DNA-protein interactions, we demonstrate that LIKE-XL enables the discovery of low-affinity transcription-factor/DNA interactions via sequence-specific DNA baits, determining the binding sites for transcription factors that have been previously unknown. More importantly, we successfully decipher the dynamics of the transcription factor subproteome in response to drug treatment in a time-resolved manner, and find downstream target transcription factors from drug perturbations, providing insight into their dynamic transcriptional networks. The LIKE-XL strategy offers a complementary method to expand the DNA-protein profiling toolbox and map accurate DNA-protein interactomes that were previously inaccessible via non-covalent strategies, for better understanding of protein function in health and disease.


Subject(s)
DNA , Transcription Factors , Transcription Factors/chemistry , DNA/chemistry , Amines/chemistry , Protein Binding , Cross-Linking Reagents/chemistry
20.
Inorg Chem ; 51(7): 4035-42, 2012 Apr 02.
Article in English | MEDLINE | ID: mdl-22432447

ABSTRACT

Complexation of dysprosium(III) with the heterodonor chelating ligand o-vanillin picolinoylhydrazone (H(2)ovph) in the presence of a carbonato ligand affords two novel Dy(6) and Dy(8) clusters, namely, [Dy(6)(ovph)(4)(Hpvph)(2)Cl(4)(H(2)O)(2)(CO(3))(2)]·CH(3)OH·H(2)O·CH(3)CN (2) and [Dy(8)(ovph)(8)(CO(3))(4)(H(2)O)(8)]·12CH(3)CN·6H(2)O (3). Compound 2 is composed of three petals of the Dy(2) units linked by two carbonato ligands, forming a triangular prism arrangement, while compound 3 possesses an octanuclear core with an unprecedented tub conformation, in which Dy(ovph) fragments are attached to the sides of the carbonato core. The static and dynamic magnetic properties are reported and discussed. In the Dy(6) aggregate, three Dy(2) "skeletons", having been well preserved (see the scheme), contribute to the single-molecule-magnet behavior with a relatively slow tunneling rate, while the Dy(8) cluster only exhibits a rather small relaxation barrier.

SELECTION OF CITATIONS
SEARCH DETAIL