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

Objective To compare the application effects of plankton multiplex polymerase chain reac-tion-capillary electrophoresis(PCR-CE),SYBR Green Ⅰ real-time quantitative PCR(qPCR)and microwave digestion-vacuum filtration-automated scanning electron microscopy(MD-VF-Auto SEM)in the diagnosis of drowning.Methods Lung,liver and kidney tissues from 212 drowned corpses and 30 non-drowned corpses were examined respectively by the three drowning-related plankton testing methods,and the detection rates of plankton in each tissue by three methods were compared.Results In drowned corpses,the total detection rates of PCR-CE,qPCR,and MD-VF-Auto SEM were 93.9%,96.2%,and 95.3%,respectively,with no statistically significant difference(P>0.05).The detection rate of lung tissue by MD-VF-Auto SEM(100%)was higher than those of PCR-CE and qPCR(P<0.05),and there was no significant difference in the detection rates of the three methods in liver or kidney tissues(P>0.05).In non-drowning corpses,a small number of diatoms(less than 10 cells/10 g)were detected by MD-VF-Auto SEM method,only in liver and kidney tissues,while the other two methods yielded negative results for all tissues.Conclusion All three methods have good efficacy in the examination of drowned corpses.The MD-VF-Auto SEM method directly observes diatom morpho-logical characteristics through scanning electron microscopy,and the qualitative and quantitative analy-ses are intuitive and accurate.It has great advantages in the examination of difficult degradation samples.The PCR-CE method and qPCR method have a low sample demand(0.5 g),are easy to operate and have short detection time(4-7 h).They are easy to be applied in the grassroots depart-ments and are suitable for the rapid determination of drowned corpses in routin cases.The combina-tion of the two DNA methods with the MD-VF-Auto SEM method can increase the detection rate of plankton,ensuring the reliability of examination results.This combined use is of significant importance in the application of drowning diagnosis.

OBJECTIVE To investigate the distribution and drug resistance of multidrug-resistant bacteria in the neonatal intensive care unit of a three-A children's hospital in Henan Province,and to provide reference for ational drug use in clinical practice.METHODS Clinical specimens from hospitalized newborns in neonatal intensive care unit from a three-A children's hospital from Jan.1,2019 to Dec.31,2023 were subjected to etiological exam-ination and drug sensitivity test,and to analyze the distribution and drug resistance of multidrug-resistant bacteri-a in hospitalized newborns.RESULTS During the 5-year period,1139 strains of multidrug-resistant bacteria were i-solated,including 229 gram-positive bacteria(20.11％)and 910 gram-negative bacteria(79.89％).There were 92 strains of methicillin-resistant Staphylococcus aureus(MRSA)(accounting for 8.08％),57 strains(accounting for 5.00％)of methicillin-resistant coagulase-negative Staphylococcus epidermidis and 28 strains(accounting for 2.46％)of methicillin-resistant coagulase-negative human Staphylococcus.370 strains(accounting for 32.48)of carbapenem-resistant Klebsiella pneumoniae(CRKP),268 strains(accounting for 23.53％)of extenspectrum β-lactamase-producing Escherichia coli and 85 strains(accounting for 7.46％)of K.pneumoniae,there were 767 sputum specimens(67.34％),160 blood specimens from peripheral intravenous puncture and central venous cath-eterization(PICC)(14.05％),63 bronchoalveolar lavage fluid specimens(5.53％),29 secretion specimens(eye and wound secretions)(2.54％),and 120 other specimens(10.54％).K.pneumoniae and E.coli producing su-per-broad spectrum β-lactamase,CRKP and MRSA were the main drug-resistant bacteria.CONCLUSION The sit-uation of drug resistance in neonatal intensive care unit is serious,therefore monitoring bacterial resistance should be strengthened according to the clinical laboratory results,and antibiotics should be applied rationally.

Objective:To investigate the efficacy and safety of bendamustine combined with anti-CD20 monoclonal antibody in the first-line treatment of older patients with indolent B-cell non-Hodgkin lymphoma (B-iNHL) .Methods:The clinical data of 159 patients with B-iNHL enrolled in 16 hospitals from Jiangsu Cooperative Lymphoma Group from December 1, 2019, to April 20, 2024, were analyzed for regimen efficacy and safety. Bendamustine plus rituximab (BR) and bendamustine plus obinutuzumab (BG) were administered to 139 (87.4% ) and 20 (12.6% ) patients, respectively.Results:Among the 159 patients, 101 (63.5% ) were male and 58 (36.5% ) were female, with a median age of 69 years (range: 60–84). Efficacy could be assessed in 138 (86.8% ) patients. The efficacy assessment demonstrated that the overall response rate was 92.0% with complete and partial remissions in 75 (54.3% ) and 52 (37.7% ) cases, respectively. With a median follow-up of 24 months (range: 4–64), the progression-free survival rate was (87.5 ± 3.0) % and the overall survival rate was (83.2 ± 3.3) %. Of the 27 patients who died, 6 (22.2% ) died due to disease progression. The mean applied dose of bendamustine per cycle was 73.0 (50.8–89.7) mg/m 2 per day, administered on days 1 and 2. Adverse events of grade 3 or higher were reported in 53 (33.3% ) patients, with infection (30 cases,18.9% ) and neutropenia (24 cases, 15.1% ) demonstrating the highest incidence. Conclusion:Bendamustine combined with anti-CD20 monoclonal antibody demonstrated good efficacy and is well-tolerated in the first-line treatment of elderly patients with B-iNHL.

Aim To investigate the neuroprotective effect of Takeda G protein-coupled receptor-5(TGR5)activated by INT-777 on hypoxic-ischemic encephalop-athy(HIE)in neonatal rats.Methods Seven-day-old SD rats were randomly divided into the sham opera-tion group(Sham,S),model group(HIE,G),INT-777 low-dose(L),medium-dose(M),and high-dose(H)groups.The modified Rice-Vanucci method was used to construct the HIE model and Intranasal admin-istration 1 h after modeling.Short-term neurobehavioral tests were performed 48 h after modeling to evaluate the neurological function of neonatal rats,TTC staining was used to determine the volume of cerebral infarction,dry and wet specific gravity was used to determine the brain water content,ferrous ion kit was used to deter-mine the brain ferrous ion content,HE staining was used to observe the pathological damage of brain tis-sue,Nissl staining was used to observe the loss of Nissl substance,Transmission electron microscopy(TEM)was used to observe the mitochondrial morphological changes of cortical neurons,and Western blot was em-ployed to detect the expression of ferroptosis-related proteins TFR1 and GPX4.Results Compared with group S,group G had increased short-term neurobehav-ioral test consumption time,higher scores,increased cerebral infarct volume,brain water content,and brain ferrous iron content,significant brain tissue damage on the affected side,severe loss of Nissl substance,smaller neuronal mitochondria,decreased mitochondrial cris-tae,and increased expression of TFR1 and reduced ex-pression of GPX4.Compared with group G,the INT-777 administration group had a shorter consumption time for short-term neurobehavioral tests,lower scores,the cerebral infarction volume,brain water content,and brain ferrous ion content decreased,the brain tissue damage on the affected side was reduced,and there was insignificant loss of Nissl substance,larger neuronal mi-tochondrial volume,increased mitochondrial cristae,re-duced expression of TFR1,and increased expression of GPX4.Conclusions INT-777 agonist TGR5 has a protective effect against hypoxic-ischemic encephalopa-thy in neonatal rats,and its mechanism of action may be related to the inhibition of neuronal ferroptosis.

Aim To investigate the neuroprotective effect of Takeda G protein-coupled receptor-5(TGR5)activated by INT-777 on hypoxic-ischemic encephalop-athy(HIE)in neonatal rats.Methods Seven-day-old SD rats were randomly divided into the sham opera-tion group(Sham,S),model group(HIE,G),INT-777 low-dose(L),medium-dose(M),and high-dose(H)groups.The modified Rice-Vanucci method was used to construct the HIE model and Intranasal admin-istration 1 h after modeling.Short-term neurobehavioral tests were performed 48 h after modeling to evaluate the neurological function of neonatal rats,TTC staining was used to determine the volume of cerebral infarction,dry and wet specific gravity was used to determine the brain water content,ferrous ion kit was used to deter-mine the brain ferrous ion content,HE staining was used to observe the pathological damage of brain tis-sue,Nissl staining was used to observe the loss of Nissl substance,Transmission electron microscopy(TEM)was used to observe the mitochondrial morphological changes of cortical neurons,and Western blot was em-ployed to detect the expression of ferroptosis-related proteins TFR1 and GPX4.Results Compared with group S,group G had increased short-term neurobehav-ioral test consumption time,higher scores,increased cerebral infarct volume,brain water content,and brain ferrous iron content,significant brain tissue damage on the affected side,severe loss of Nissl substance,smaller neuronal mitochondria,decreased mitochondrial cris-tae,and increased expression of TFR1 and reduced ex-pression of GPX4.Compared with group G,the INT-777 administration group had a shorter consumption time for short-term neurobehavioral tests,lower scores,the cerebral infarction volume,brain water content,and brain ferrous ion content decreased,the brain tissue damage on the affected side was reduced,and there was insignificant loss of Nissl substance,larger neuronal mi-tochondrial volume,increased mitochondrial cristae,re-duced expression of TFR1,and increased expression of GPX4.Conclusions INT-777 agonist TGR5 has a protective effect against hypoxic-ischemic encephalopa-thy in neonatal rats,and its mechanism of action may be related to the inhibition of neuronal ferroptosis.

OBJECTIVE To investigate the distribution and drug resistance of multidrug-resistant bacteria in the neonatal intensive care unit of a three-A children's hospital in Henan Province,and to provide reference for ational drug use in clinical practice.METHODS Clinical specimens from hospitalized newborns in neonatal intensive care unit from a three-A children's hospital from Jan.1,2019 to Dec.31,2023 were subjected to etiological exam-ination and drug sensitivity test,and to analyze the distribution and drug resistance of multidrug-resistant bacteri-a in hospitalized newborns.RESULTS During the 5-year period,1139 strains of multidrug-resistant bacteria were i-solated,including 229 gram-positive bacteria(20.11％)and 910 gram-negative bacteria(79.89％).There were 92 strains of methicillin-resistant Staphylococcus aureus(MRSA)(accounting for 8.08％),57 strains(accounting for 5.00％)of methicillin-resistant coagulase-negative Staphylococcus epidermidis and 28 strains(accounting for 2.46％)of methicillin-resistant coagulase-negative human Staphylococcus.370 strains(accounting for 32.48)of carbapenem-resistant Klebsiella pneumoniae(CRKP),268 strains(accounting for 23.53％)of extenspectrum β-lactamase-producing Escherichia coli and 85 strains(accounting for 7.46％)of K.pneumoniae,there were 767 sputum specimens(67.34％),160 blood specimens from peripheral intravenous puncture and central venous cath-eterization(PICC)(14.05％),63 bronchoalveolar lavage fluid specimens(5.53％),29 secretion specimens(eye and wound secretions)(2.54％),and 120 other specimens(10.54％).K.pneumoniae and E.coli producing su-per-broad spectrum β-lactamase,CRKP and MRSA were the main drug-resistant bacteria.CONCLUSION The sit-uation of drug resistance in neonatal intensive care unit is serious,therefore monitoring bacterial resistance should be strengthened according to the clinical laboratory results,and antibiotics should be applied rationally.

Objective:To investigate the efficacy and safety of bendamustine combined with anti-CD20 monoclonal antibody in the first-line treatment of older patients with indolent B-cell non-Hodgkin lymphoma (B-iNHL) .Methods:The clinical data of 159 patients with B-iNHL enrolled in 16 hospitals from Jiangsu Cooperative Lymphoma Group from December 1, 2019, to April 20, 2024, were analyzed for regimen efficacy and safety. Bendamustine plus rituximab (BR) and bendamustine plus obinutuzumab (BG) were administered to 139 (87.4% ) and 20 (12.6% ) patients, respectively.Results:Among the 159 patients, 101 (63.5% ) were male and 58 (36.5% ) were female, with a median age of 69 years (range: 60–84). Efficacy could be assessed in 138 (86.8% ) patients. The efficacy assessment demonstrated that the overall response rate was 92.0% with complete and partial remissions in 75 (54.3% ) and 52 (37.7% ) cases, respectively. With a median follow-up of 24 months (range: 4–64), the progression-free survival rate was (87.5 ± 3.0) % and the overall survival rate was (83.2 ± 3.3) %. Of the 27 patients who died, 6 (22.2% ) died due to disease progression. The mean applied dose of bendamustine per cycle was 73.0 (50.8–89.7) mg/m 2 per day, administered on days 1 and 2. Adverse events of grade 3 or higher were reported in 53 (33.3% ) patients, with infection (30 cases,18.9% ) and neutropenia (24 cases, 15.1% ) demonstrating the highest incidence. Conclusion:Bendamustine combined with anti-CD20 monoclonal antibody demonstrated good efficacy and is well-tolerated in the first-line treatment of elderly patients with B-iNHL.

Eleven compounds were isolated from the ethyl acetate fraction of the 95% aqueous ethanol extract of the roots of Sophora tonkinensis by silica gel, ODS, Sephadex LH-20 column chromatography, and semi-preparative RP-HPLC. Their structures were identified as 7-hydroxy-8-isopentenylchromone (1), furo[2,3-f]-1,3-benzodioxole-7-carboxylic acid (2), 6-[3-(2′,4′-dihydroxyphenyl)acryloyl]-7-hydroxy-2,2-dimethyl-8-(3-methyl-2-butenyl)-2H-benzopyran (3), flemichapparin B (4), tectorigenin (5), genistein (6), 6-hydroxy-1,3-benzodioxole-5-carboxylic acid (7), vanillic acid (8), protocatechuic acid (9), 2,4-dihydroxybenzoic acid (10), and p-hydroxybenzoic acid (11) through extensive spectroscopic data (IR, UV, HR-ESI-MS, and NMR spectra). Among them, compounds 1 and 2 were new compounds. In addition, compound 3 showed significant α-glucosidase and protein tyrosine phosphatase-1B (PTP1B) inhibitory activities with IC₅₀ values of 5.595 and 0.320 μmol·L^-1, respectively.

Aim To disclose the subcellular localiza-tion,expression pattern,cellular physiological function and possible molecular mechanism of C12ORF56,a novel gene located at q14.2 of chromosome 12,in the pathogenesis of lung cancer.Methods ONCOMINE database was applied to investigate the mRNA level dif-fering of C12ORF56 between normal and lung cancer tissues.Analysis based on LinkedOmics,Metascape,String and GSEA database or tools provided indication of potential cellular physiological functions of C12ORF56 in the developing of lung cancer.C12ORF56 was knocked down via siRNA and the pro-liferation of NCI-H1073 cells were observed by EdU and CCK-8 assay.RT-qPCR was used to detect the ex-pression level of C12ORF56 of lung cancer cells on dif-ferent cycle phases.The core sequence regions of pro-moter affecting the transcription of C12ORF56 gene were analyzed by Jaspar online-tools and verified by dual-luciferase assay.Results C12ORF56 was highly expressed in lung cancer cells,especially in squamous cell lung cancer.C12ORF56 correlated with cell cy-cle,cancer immune,DNA replication.Knockdown of C12ORF56 reduced NCI-H1703 cell proliferation.Conclusion The up-regulation of C12ORF56 is in-volved in the development of lung cancer by enhancing lung cancer cell proliferation.