Although a single nucleotide polymorphism for N-acetyltransferase 10 (NAT10) has been identified in patients with early-onset stroke, the role of NAT10 in ischemic injury and the related underlying mechanisms remains elusive. Here, we provide evidence that NAT10, the only known RNA N4-acetylcytidine (ac4C) modification "writer", is increased in the damaged cortex of patients with acute ischemic stroke and the peri-infarct cortex of mice subjected to photothrombotic (PT) stroke. Pharmacological inhibition of NAT10 with remodelin on Days 3-7 post-stroke or astrocytic depletion of NAT10 via targeted virus attenuates ischemia-induced infarction and improves functional recovery in PT mice. Mechanistically, NAT10 enhances ac4C acetylation of the inflammatory cytokine tissue inhibitor of metalloproteinase 1 (Timp1) mRNA transcript, which increases TIMP1 expression and results in the accumulation of microtubule-associated protein 1 light chain 3 (LC3) and progression of astrocyte autophagy. These findings demonstrate that NAT10 regulates astrocyte autophagy by targeting Timp1 ac4C after stroke. This study highlights the critical role of ac4C in the regulation of astrocyte autophagy and proposes a promising strategy to improve post-stroke outcomes via NAT10 inhibition.

DNA methylation is an important epigenetic modification in mammals, playing a crucial role in various physiological processes, including cell differentiation and the gene expression regulation. The ten-eleven translocation (TET) protein family of DNA demethylases is integral to the regulation of DNA methylation, as it catalyzes the oxidation of 5-methylcytosine to form 5-hydroxymethylcytosine. During early embryonic development, the genome undergoes extensive DNA demethylation, and any aberration in this reprogramming process can result in abnormal embryonic development and physiological defects in offspring. The TET proteins, due to their unique dynamics and multifaceted roles, facilitate DNA demethylation and are involved in development and maturation of germ cells, the establishment of pluripotency, cell lineage differentiation, and transcriptional processes throughout mammalian embryogenesis. Furthermore, these proteins are closely associated with the maintenance of pregnancy and susceptibility of progeny to disease. Factors such as genetic mutations, maternal health conditions, and exposure to adverse environmental influences can impact TET protein activity, resulting in abnormal patterns of DNA demethylation. A comprehensive investigation of the related mechanisms of TET proteins is essential for enhancing our understanding of epigenetic regulation during early life, diagnosing and treating related diseases such as early fetal development retardation, and informing strategies for the prevention and management of pregnancy.This article reviews the regulatory role of DNA demethylation mediated by TET protein in mammalian embryonic development and pregnancy outcomes.

AIM:To compare the formation and release of neutrophil extracellular traps(NETs)af-ter exposure to the high-altitude hypoxic environ-ment for different periods,and their relationship with the dynamic changes of microcirculatory disor-ders associated with pulmonary edema.METH-ODS:SD rats were raised under normoxic condi-tions at an altitude of 400 m and under hypoxic conditions at an altitude of 4 200 m.The rats raised under hypoxic conditions at an altitude of 4 200 m for 7 days were returned to normoxic con-ditions at 400 m to observe the changes in physio-logical and pathological indicators of the rats.The dynamic changes of neutrophil extracellular traps(NETs)release and microcirculatory disorders relat-ed to pulmonary edema after high-altitude hypoxia exposure and after returning to the plain were ex-plored by blood routine determination,rat arterial blood gas analysis,ELISA experiment,lung water content determination,H&E staining,and immuno-histochemical staining.RESULTS:In the hypoxic en-vironment at 4 200 m,rats exhibited significant re-ductions in arterial oxygen saturation(SaO2)and partial pressure of oxygen(PO2)(P＜0.01),accompa-nied by a marked increase in lung-tissue water con-tent(P＜0.01).The complete blood count revealed elevated levels of red blood cells,white blood cells,lymphocytes,and neutrophils(P＜0.01).In addition,the formation and release of NETs in neutrophils in-creased,accompanied by an aggravation of the in-flammatory response.After returning to the low-al-titude normoxic area at 400 m,the above indica-tors gradually returned to normal levels on the 7th day.Pathological changes such as alveolar epitheli-al cell shedding and inflammatory cell infiltration were observed in the lung tissues of rats in the high-altitude area,and the pathological changes were restored after returning to the low-altitude normoxic environment.CONCLUSION:The release of NETs from neutrophils is closely related to the re-covery of pulmonary edema and pulmonary ede-ma-related microcirculatory disorders after high-al-titude hypoxia exposure.

DNA methylation is an important epigenetic modification in mammals, playing a crucial role in various physiological processes, including cell differentiation and the gene expression regulation. The ten-eleven translocation (TET) protein family of DNA demethylases is integral to the regulation of DNA methylation, as it catalyzes the oxidation of 5-methylcytosine to form 5-hydroxymethylcytosine. During early embryonic development, the genome undergoes extensive DNA demethylation, and any aberration in this reprogramming process can result in abnormal embryonic development and physiological defects in offspring. The TET proteins, due to their unique dynamics and multifaceted roles, facilitate DNA demethylation and are involved in development and maturation of germ cells, the establishment of pluripotency, cell lineage differentiation, and transcriptional processes throughout mammalian embryogenesis. Furthermore, these proteins are closely associated with the maintenance of pregnancy and susceptibility of progeny to disease. Factors such as genetic mutations, maternal health conditions, and exposure to adverse environmental influences can impact TET protein activity, resulting in abnormal patterns of DNA demethylation. A comprehensive investigation of the related mechanisms of TET proteins is essential for enhancing our understanding of epigenetic regulation during early life, diagnosing and treating related diseases such as early fetal development retardation, and informing strategies for the prevention and management of pregnancy.This article reviews the regulatory role of DNA demethylation mediated by TET protein in mammalian embryonic development and pregnancy outcomes.

OBJECTIVE To explore the clinical characteristics and risk factors for refractory drug-resistant Pseudo-monas aeruginosa infection and evaluate the prognosis so as to provide theoretical bases for effective prevention and control of the refractory drug-resistant P.aeruginosa infection.METHODS A total of 95 patients who were di-agnosed with refractory drug-resistant P.aeruginosa infection and were treated in People's Hospital of Guangdong Province from Jan.2019 to Dec.2023 were assigned as the infection group.Meanwhile,95 patients who did not have drug-resistant P.aeruginosa infection,matched by the age and hospitalization period,were chosen as the non-infection group in a case-control(1∶1 ratio).The basic information and clinical data were collected from the two groups of patients.The characteristics and risk factors for the drug-resistant P.aeruginosa infection were ana-lyzed,and the prognosis of the patients was evaluated.RESULTS Among the clinical isolates of drug-resistant P.aeruginosa,78 were isolated from respiratory secretions;there were 59 patients from intensive care unit(ICU),13 patients from respiratory medicine department and 8 patients from geriatrics department.Fever,dyspnea,moist rales and cough were the major clinical manifestations.The proportions of patients with history of respirato-ry tract disease(P＜0.001),renal disease(P=0.008),nervous system disease(P=0.005),diabetes mellitus(P=0.017),hepatic disease(P=0.007),previous utilization rate of aminoglycosides(P=0.002)and previous u-tilization rate of no less than 3 types of antibiotics were higher in the infection group than in the non-infection group.Multivariate analysis showed that the history of respiratory tract disease(OR=2.813,95％CI:1.366 to 5.792,P=0.005),history of diabetes mellitus(OR=2.465,95％CI:1.129 to 5.382,P=0.024)and history of nervous system disease(OR=2.386,95％CI:1.151 to 4.944,P=0.019)were the risk factors for the drug-resist-ant P.aeruginosa infection.The mortality rate of the infection group was 30.53％,higher than 6.32％of the non-infection group(x2=18.527,P＜0.001).CONCLUSIONS The mortality rate of the patients with drug-resistant P.aeruginosa infection is high.The history of respiratory tract disease,history of diabetes mellitus and history of nervous system disease are the major risk factors for the infection.It is necessary for the hospital to strengthen the awareness of prevention of the drug-resistant P.aeruginosa infection so as to curb the hospital-associated infection.

Tyrosine kinase inhibitors(TKIs)are the key agent in the treatment of renal cell carcino-ma(RCC)so far.Drugs such as sunitinib and sorafenib showed significant benefits RCC patients,however,the adverse effect,drug efficacy and drug resistance limited the use of these therapy.Espe-cially the drug resistant issue brings up a big chal-lenge for clinical practice,and the mechanisms un-derlying are still poorly understood.In recent years,new therapies have been combined with TKIs to improve the treatment outcome.Immuno-therapy,combination therapy with other TKIs,tar-geted nanoparticle delivery,and drug modification are widely studied to improve the efficacies of TKIs and regain the sensitivity.In this review,we sum-marizes the current understanding of TKI drug resis-tance and the approaches to regaining drug sensi-tivity.

AIM:To compare the formation and release of neutrophil extracellular traps(NETs)af-ter exposure to the high-altitude hypoxic environ-ment for different periods,and their relationship with the dynamic changes of microcirculatory disor-ders associated with pulmonary edema.METH-ODS:SD rats were raised under normoxic condi-tions at an altitude of 400 m and under hypoxic conditions at an altitude of 4 200 m.The rats raised under hypoxic conditions at an altitude of 4 200 m for 7 days were returned to normoxic con-ditions at 400 m to observe the changes in physio-logical and pathological indicators of the rats.The dynamic changes of neutrophil extracellular traps(NETs)release and microcirculatory disorders relat-ed to pulmonary edema after high-altitude hypoxia exposure and after returning to the plain were ex-plored by blood routine determination,rat arterial blood gas analysis,ELISA experiment,lung water content determination,H&E staining,and immuno-histochemical staining.RESULTS:In the hypoxic en-vironment at 4 200 m,rats exhibited significant re-ductions in arterial oxygen saturation(SaO2)and partial pressure of oxygen(PO2)(P＜0.01),accompa-nied by a marked increase in lung-tissue water con-tent(P＜0.01).The complete blood count revealed elevated levels of red blood cells,white blood cells,lymphocytes,and neutrophils(P＜0.01).In addition,the formation and release of NETs in neutrophils in-creased,accompanied by an aggravation of the in-flammatory response.After returning to the low-al-titude normoxic area at 400 m,the above indica-tors gradually returned to normal levels on the 7th day.Pathological changes such as alveolar epitheli-al cell shedding and inflammatory cell infiltration were observed in the lung tissues of rats in the high-altitude area,and the pathological changes were restored after returning to the low-altitude normoxic environment.CONCLUSION:The release of NETs from neutrophils is closely related to the re-covery of pulmonary edema and pulmonary ede-ma-related microcirculatory disorders after high-al-titude hypoxia exposure.

OBJECTIVE To explore the clinical characteristics and risk factors for refractory drug-resistant Pseudo-monas aeruginosa infection and evaluate the prognosis so as to provide theoretical bases for effective prevention and control of the refractory drug-resistant P.aeruginosa infection.METHODS A total of 95 patients who were di-agnosed with refractory drug-resistant P.aeruginosa infection and were treated in People's Hospital of Guangdong Province from Jan.2019 to Dec.2023 were assigned as the infection group.Meanwhile,95 patients who did not have drug-resistant P.aeruginosa infection,matched by the age and hospitalization period,were chosen as the non-infection group in a case-control(1∶1 ratio).The basic information and clinical data were collected from the two groups of patients.The characteristics and risk factors for the drug-resistant P.aeruginosa infection were ana-lyzed,and the prognosis of the patients was evaluated.RESULTS Among the clinical isolates of drug-resistant P.aeruginosa,78 were isolated from respiratory secretions;there were 59 patients from intensive care unit(ICU),13 patients from respiratory medicine department and 8 patients from geriatrics department.Fever,dyspnea,moist rales and cough were the major clinical manifestations.The proportions of patients with history of respirato-ry tract disease(P＜0.001),renal disease(P=0.008),nervous system disease(P=0.005),diabetes mellitus(P=0.017),hepatic disease(P=0.007),previous utilization rate of aminoglycosides(P=0.002)and previous u-tilization rate of no less than 3 types of antibiotics were higher in the infection group than in the non-infection group.Multivariate analysis showed that the history of respiratory tract disease(OR=2.813,95％CI:1.366 to 5.792,P=0.005),history of diabetes mellitus(OR=2.465,95％CI:1.129 to 5.382,P=0.024)and history of nervous system disease(OR=2.386,95％CI:1.151 to 4.944,P=0.019)were the risk factors for the drug-resist-ant P.aeruginosa infection.The mortality rate of the infection group was 30.53％,higher than 6.32％of the non-infection group(x2=18.527,P＜0.001).CONCLUSIONS The mortality rate of the patients with drug-resistant P.aeruginosa infection is high.The history of respiratory tract disease,history of diabetes mellitus and history of nervous system disease are the major risk factors for the infection.It is necessary for the hospital to strengthen the awareness of prevention of the drug-resistant P.aeruginosa infection so as to curb the hospital-associated infection.

Tyrosine kinase inhibitors(TKIs)are the key agent in the treatment of renal cell carcino-ma(RCC)so far.Drugs such as sunitinib and sorafenib showed significant benefits RCC patients,however,the adverse effect,drug efficacy and drug resistance limited the use of these therapy.Espe-cially the drug resistant issue brings up a big chal-lenge for clinical practice,and the mechanisms un-derlying are still poorly understood.In recent years,new therapies have been combined with TKIs to improve the treatment outcome.Immuno-therapy,combination therapy with other TKIs,tar-geted nanoparticle delivery,and drug modification are widely studied to improve the efficacies of TKIs and regain the sensitivity.In this review,we sum-marizes the current understanding of TKI drug resis-tance and the approaches to regaining drug sensi-tivity.

Objective:The drug-resistant genes carried by carbapenem-resistant Klebsiella pneumoniae(CRKP)limit clinical treatment options,and its virulence genes severely affect patient prognosis.This study aims to investigate the distribution of virulence genes,capsular serotypes,and molecular epidemiological characteristics of CRKP in ICU,to understand the characteristics of CRKP infections in ICU,and to provide a scientific basis for effective monitoring and control of CRKP infections in ICU. Methods:A total of 40 non-duplicate strains of CRKP isolated from the ICU of Guangdong Provincial People's Hospital between January 2021 and December 2022 were collected and analyzed.Whole-genome sequencing was used to analyze the distribution of resistance genes,virulence genes,and capsular serotypes of the strains.The sequences of 7 housekeeping genes of CRKP genome were uploaded to the Klebsiella pneumoniae(KPN)multilocus sequence typing(MLST)database to determine the sequence types(STs)of the strains. Results:The age of the 40 ICU CRKP-infected patients was(69.03±17.82)years old,with various underlying diseases,and there were 20 patients with improved clinical outcome and 20 patients with death.The isolated strains primarily originated from mid-stream urine and bronchoalveolar lavage fluid.Whole-genome sequencing results revealed that the strains predominantly carried blaKPC-1(29 strains,72.5%)and blaNDM-1(6 strains,15.0%),with 5 strains carrying both blaKPC-1 and blaNDM-1.Various virulence genes were detected,among which the carriage rates of genes such as entA,entB,entE,entS,fepA,fepC,fepG,yag/ecp,and ompA reached 100%,while the carriage rates of genes such as entD,fimB,iroB,iroD,fes,and pla were low.The CRKP strains isolated from ICU were predominantly ST11(27 cases,67.5%),with KL64 being the main capsular serotype(29 cases,72.5%).A total of 23 ST11-KL64 CRKP strains were detected,accounting for 57.5%. Conclusion:The main type of ICU CRKP is ST11-KL64,carrying various virulence genes,primarily those related to iron absorption.Furthermore,blaKPC has shifted from blaKPC-2 to blaKPC-1.Therefore,close monitoring of the molecular epidemiological changes of CRKP is necessary,and strict control measures should be implemented to effectively curb the occurrence of CRKP infections.