OBJECTIVE: CRISPR-Cas protects bacteria from exogenous DNA invasion and is associated with bacterial biofilm formation and pathogenicity. METHODS: We analyzed the type I-F CRISPR-Cas system of Legionella pneumophila WX48, including Cas1, Cas2-Cas3, Csy1, Csy2, Csy3, and Cas6f, along with downstream CRISPR arrays. We explored the effects of the CRISPR-Cas system on the in vitro growth, biofilm-forming ability, and pathogenicity of L. pneumophila through constructing gene deletion mutants. RESULTS: The type I-F CRISPR-Cas system did not affect the in vitro growth of wild-type or mutant strains. The biofilm formation and intracellular proliferation of the mutant strains were weaker than those of the wild type owing to the regulation of type IV pili and Dot/Icm type IV secretion systems. In particular, Cas6f deletion strongly inhibited these processes. CONCLUSION The type I-F CRISPR-Cas system may reduce biofilm formation and intracellular proliferation in L. pneumophila.
Legionella pneumophila/pathogenicity* ; CRISPR-Cas Systems ; Biofilms/growth & development* ; Phenotype ; Bacterial Proteins/metabolism* ; Gene Deletion

Travelling wave structures for lossless ion manipulations(TW-SLIM)employ travelling wave electric fields to propel ions forward,enabling exceptionally long transmission paths and holding great potential for applications in material transportation and separation.In this study,different from previous studies focusing on the transport performance of macromolecules such as proteins in TW-SLIM,the transmission performance of small molecules(<200 amu)was investigated and analyzed in the turning TW-SLIM through the COMSOL simulation platform,to explore the influence of electrostatic field of protective electrode and radio frequency(RF)electric field on ion transport efficiency,and obtain the optimal value.Compared to macromolecules,small molecules required lower voltage amplitudes from guard electrodes but stricter requirements in terms of the peak-to-peak amplitude and frequency of RF voltage for lossless transmission.Using dimethyl methylphosphonate(DMMP)as a sample and testing it on the TW-SLIM experimental platform,when the protective voltage amplitude was 5 V and the peak-to-peak voltage of the radio-frequency electrode was 440 V at 1.5 MHz,the ion transmission efficiency reached 100%,achieving lossless transmission.The experimental results provided valuable references for application of TW-SLIM in separation and detection of small molecular substances,such as explosives and drugs.

In the field of substance detection,ion dissociation techniques have become crucial for enhancing qualitative accuracy.By applying external energy to induce dissociation of ions in the substance being analyzed,the internal structural information can be obtained,thereby improving qualitative capabilities.Current research on ion dissociation techniques primarily focuses on tandem mass spectrometry,which typically requires a vacuum environment.However,research on ambient ion dissociation techniques is less developed,with some progress made in the field of tandem ion mobility spectrometry.Recently,the development of field-induced dissociation(FID)in this area has enabled ambient dissociation of various explosive and volatile alcohol ions.Nevertheless,the limitation imposed by the maximum breakdown field of air restricts the energy of the electric field,making it challenging to dissociate ions with high energy requirements,such as those of drugs.To address this issue,in this work,an ambient heat-induced dissociation(HID)technique based on high temperatures was proposed,in which an ambient ion heat-induced dissociation unit was developed and integrated into a home-made ion trap mass spectrometer.Experiments were conducted on four representative drug samples,e.g.methamphetamine,heroin,cocaine,and ketamine.The parent ions mass spectra,low vacuum collision-induced dissociation(CID)mass spectra and ambient HID mass spectra for each sample were obtained.By analyzing and comparing the fragmentation products from ambient and low vacuum dissociation,the feasibility of the ambient HID technique was verified.This technique provided a method for ion dissociation in single mass analyzers without tandem mass spectrometry capability and offered a new research direction for the future development of tandem ion mobility spectrometry.

This study aimed to explore the pharmacological mechanism of Yourenji Capsules(YRJ) in improving osteoporosis by combining network pharmacology and proteomics technologies. The SD rats were randomly divided into a blank control group and a 700 mg·kg~(-1) YRJ group. The rats were subjected to gavage administration with the corresponding drugs, and the blank serum, drug-containing serum, and YRJ samples were compared using ultra performance liquid chromatography-quadrupole time-of-flight tandem mass spectrometry(UPLC-Q-TOF-MS/MS) to analyze the main components absorbed into blood. Network pharmacology analysis was conducted based on the YRJ components absorbed into blood to obtain related targets of the components and target genes involved in osteoporosis, and Venn diagrams were used to identify the intersection of drug action targets and disease targets. The STRING database was used for protein-protein interaction(PPI) network analysis of potential target proteins to construct a PPI network. Gene Ontology(GO) functional enrichment and Kyoto Encyclopedia of Genes and Genomes(KEGG) pathway enrichment were performed using Enrichr to investigate the potential mechanism of action of YRJ. Ovariectomy(OVX) was performed to establish a rat model of osteoporosis, and the rats were divided into a sham group, a model group, and a 700 mg·kg~(-1) YRJ group. The rats were given the corresponding drugs by gavage. The femurs of the rats were subjected to label-free proteomics analysis to detect differentially expressed proteins, and GO functional enrichment and KEGG pathway enrichment analyses were performed on the differentially expressed proteins. With the help of network pharmacology and proteomics results, the mechanism by which YRJ improves osteoporosis was predicted. The analysis of the YRJ components absorbed into blood revealed 23 bioactive components of YRJ, and network pharmacology results indicated that key targets involved include tumor necrosis factor(TNF), tumor protein p53(TP53), protein kinase(AKT1), and matrix metalloproteinase 9(MMP9). These targets are mainly involved in osteoclast differentiation, estrogen signaling pathways, and nuclear factor-kappa B(NF-κB) signaling pathways. Additionally, the proteomics analysis highlighted important pathways such as peroxisome proliferator-activated receptor(PPAR) signaling pathways, mitogen-activated protein kinase(MAPK) signaling pathways, and β-alanine metabolism. The combined approaches of network pharmacology and proteomics have revealed that the mechanism by which YRJ improves osteoporosis may be closely related to the regulation of inflammation, osteoblast, and osteoclast metabolic pathways. The main pathways involved include the NF-κB signaling pathways, MAPK signaling pathways, and PPAR signaling pathways, among others.
Animals ; Drugs, Chinese Herbal/administration & dosage* ; Osteoporosis/metabolism* ; Proteomics ; Rats ; Rats, Sprague-Dawley ; Network Pharmacology ; Female ; Protein Interaction Maps/drug effects* ; Capsules ; Humans ; Signal Transduction/drug effects*

To formulate an expert consensus on the principles of preoperative hair removal and provide scientific guidance for standardized removal of hair before surgical procedures so as to reduce the incidence of surgical site infections.METHODS Led by the Hospital Management Institute of National Health Commission of the People's Republic of China,this consensus was reached with the joint efforts from the expects of relevant fields such as surgeries,interventional therapies,nursing,and infection prevention and control.The consensus facilitates the classification and evaluation of literatures by following the evidence grade formulated by Oxford Evidence-based Medicine Center and focuses on the association of preoperative hair removal with surgical site infection,it reaches the evidence grade of expert consensus and recommendation intensity by integrating with discussions on meetings and clinical experience of the expects from relevant fields.RESULTS A total of 6 items of consensus were reached by summarizing the latest evidence on the aspects including the indications for preoperative hair removal,tools,range,timing and places.CONCLUSION The consensus,to some extent,make supplements to and complete the exiting regulations and standards.It provides guidance for the medical institutions to carry out the preoperative hair removal.

To formulate an expert consensus on the principles of preoperative hair removal and provide scientific guidance for standardized removal of hair before surgical procedures so as to reduce the incidence of surgical site infections.METHODS Led by the Hospital Management Institute of National Health Commission of the People's Republic of China,this consensus was reached with the joint efforts from the expects of relevant fields such as surgeries,interventional therapies,nursing,and infection prevention and control.The consensus facilitates the classification and evaluation of literatures by following the evidence grade formulated by Oxford Evidence-based Medicine Center and focuses on the association of preoperative hair removal with surgical site infection,it reaches the evidence grade of expert consensus and recommendation intensity by integrating with discussions on meetings and clinical experience of the expects from relevant fields.RESULTS A total of 6 items of consensus were reached by summarizing the latest evidence on the aspects including the indications for preoperative hair removal,tools,range,timing and places.CONCLUSION The consensus,to some extent,make supplements to and complete the exiting regulations and standards.It provides guidance for the medical institutions to carry out the preoperative hair removal.

The cobalt sulphide nickel ternary material(NiCo2S4)prepared by hydrothermal method in this work was combined with multi-walled carbon nanotubes(MWCNT)for constructing an electrochemical sensor for quantitative detection of rutin.The morphology and crystal of the electrochemical materials were characterized by scanning electron microscopy and X-ray diffractometer,and the electrochemical behavior of the glassy carbon electrode(GCE)modified with NiCo2S4/MWCNT composites was investigated.The experimental results showed that the electrochemical redox process of two electrons and two protons occurred on the surface of modified electrode NiCo2S4/MWCNT/GCE.Under the optimized conditions,the linear range for detection of rutin by square-wave voltammetry(SWV)using this sensor was 0.06-14.8 μmol/L and the detection limit was 14.3 nmol/L.The electrochemical sensor was sensitive,simple and low-cost,with good reproducibility and reliable stability,and could be used for detection of rutin in real samples such as compound rutin tablets and color chrysanthemi tablets,with spiked recoveries of 99.5%-102.0%.

AIM To establish a UPLC-MS/MS method for the simultaneous content determination of hyperoside,kaempferol-3-O-rutinoside,esculin,chlorogenic acid,berberine,quercetin,rehmannioside D,palmatine,leonurin A,paeoniflorin,timosaponin BⅡand rutin in Guanhuangmu Granules.METHODS The analysis was performed on a 40℃ thermostatic Acquity UPLC HSS T3 column(100 mm×2.1 mm,1.8 μm),with the mobile phase comprising of 0.05%formic acid(containing 2 mmol/L ammonium acetate)-acetonitrile flowing at 0.3 mL/min in a gradient elution manner,and electron spray ionization source was adopted in positive and negative ion scanning.RESULTS Twelve constituents showed good linear relationships within their own ranges(r＞0.999 0),whose average recoveries were 93.46%-102.01%with the RSDs of 2.13%-3.65%.CONCLUSION This rapid,accurate,stable and sensitive method can be used for the quality control of Guanhuangmu Granules.

AIM To establish a UPLC-QTOF/MS method for the analyses of chemical constituents and constituents absorbed into blood from Runing Granules.METHODS Two rats were given intragastric administration of the aqueous solution of granules,after which blood collection was made at 0,0.5,1,2,4 h.The analysis was performed on a 40℃ thermostatic Acquity UPLC BEH C18 column(100 mm×2.1 mm,1.7 μm),with the mobile phases comprising of 0.1% formic aci D-acetonitrile(positive ion)or water-acetonitrile(negative ion)flowing at 0.3 mL/min in a gradient elution manner,and electron spray ionization source was adopted in positive and negative ion scanning.RESULTS Total 166 chemical constituents were identified,containing 44 flavonoids,17 terpenes,23 alkaloids,11 saponins,29 phenolic acids,13 quinones,10 organic acids,and 19 others,along with 11 constituents absorbed into blood.CONCLUSION This accurate and stable method can provide a data support for the clinical application of Runing Granules,and lay foundations for the further researches on their quality control and material basis.