Objective This study aimed to comprehensively analyze and compare the clinicopathological features and prognosis of Chinese patients with human epidermal growth factor receptor 2(HER2)-low early breast cancer(BC)and HER2-IHC0 BC. Methods Patients diagnosed with HER2-negative BC(N=999)at our institution between January 2011 and December 2015 formed our study population.Clinicopathological characteristics,association between estrogen receptor(ER)expression and HER2-low,and evolution of HER2 immunohistochemical(IHC)score were assessed.Kaplan-Meier method and log-rank test were used to compare the long-term survival outcomes(5-year follow-up)between the HER2-IHC0 and HER2-low groups. Results HER2-low BC group tended to demonstrate high expression of ER and more progesterone receptor(PgR)positivity than HER2-IHC0 BC group(P<0.001).The rate of HER2-low status increased with increasing ER expression levels(Mantel-Haenszel χ2 test,P<0.001,Pearson's R=0.159,P<0.001).Survival analysis revealed a significantly longer overall survival(OS)in HER2-low BC group than in HER2-IHC0 group(P=0.007)in the whole cohort and the hormone receptor(HR)-negative group.There were no significant differences between the two groups in terms of disease-free survival(DFS).The discordance rate of HER2 IHC scores between primary and metastatic sites was 36.84%. Conclusion HER2-low BC may not be regarded as a unique BC group in this population-based study due to similar clinicopathological features and prognostic roles.

Objective:To investigate the association of exposure to PM 2.5 and its constituents during pregnancy and fetal growth and to further identify critical windows of exposure for fetal growth. Methods:We included 4 089 mother-child pairs from the Jiangsu Birth Cohort Study between January 2016 and October 2019. Data of general characteristics, clinical information, daily average PM 2.5 exposure, and its constituents during pregnancy were collected. Fetal growth parameters, including head circumference (HC), abdominal circumference (AC), and femur length (FL), were measured by ultrasound after 20 weeks of gestation, and then estimated fetal weight (EFW) was calculated. Generalized linear mixed models were adopted to examine the associations of prenatal exposure to PM 2.5 and its constituents with fetal growth. Distributed lag nonlinear models were used to identify critical exposure windows for each outcome. Results:A 10 μg/m 3 increase in PM 2.5 exposure during pregnancy was associated with a decrease of 0.025 ( β=-0.025, 95% CI: -0.048- -0.001) in HC Z-score, 0.026 ( β=-0.026, 95% CI: -0.049- -0.003) in AC Z-score, and 0.028 ( β=-0.028, 95% CI:-0.052--0.004) in EFW Z-score, along with an increased risk of 8.5% ( RR=1.085, 95% CI: 1.010-1.165) and 13.5% ( RR=1.135, 95% CI: 1.016-1.268) for undergrowth of HC and EFW, respectively. Regarding PM 2.5 constituents, prenatal exposure to black carbon, organic matter, nitrate, sulfate (SO 42-) and ammonium consistently correlated with decreased HC Z-score. SO 42- exposure was also associated with decreased FL Z-scores. In addition, we found that gestational weeks 2-5 were critical windows for HC, weeks 4-13 and 19-40 for AC, weeks 4-13 and 23-37 for FL, and weeks 4-12 and 20-40 for EFW. Conclusions:Our findings demonstrated that exposure to PM 2.5 and its constituents during pregnancy could adversely affect fetal growth and the critical windows for different fetal growth parameters are not completely consistent.

Objective To evaluate the effects of ketamine combined with sufentanil on postoperative analgesia and depression in patients undergoing hip arthroplasty.Methods A total of 60 patients who underwent elective hip arthroplasty were selected and divided into the S group,the SK1 group and the SK2 group according to the patient-controlled intravenous analgesia regimen,with 20 cases in each group.Patients in the S group were received 2 μg/kg of sufentanil for postoperative analgesia,patients in the SK1 group were received 1 mg/kg of esketamine and 2 μg/kg of sufentanil for postoperative analgesia,and patients in the SK2 group were received 2 mg/kg of esketamine and 2 μg/kg of sufentanil for postoperative analgesia.At 1,4,24,and 48 hours after surgery,the analgesic effect of patients was evaluated using the numeric rating scale(NRS),and the sedation effect of patients was evaluated using the Ramsay sedation score.Depression of patients before and 48 hours after surgery was assessed by self-rating depression scale(SDS).The adverse reactions such as nausea and vomiting,dizziness and headache,respiratory depression,and mental symptoms within 48 hours after surgery of patients were recorded.Results The NRS scores 1,4,and 24 hours after surgery of patients in the SK1 group and the SK2 group were lower than those in the S group(P<0.05);there was no statistically significant difference in the NRS scores 48 hours after surgery of patients among the three groups(P>0.05);there was no statistically significant difference in the NRS scores at different postoperative points of patients between the SK1 and SK2 groups(P>0.05).The SDS scores 48 hours after surgery of patients in each group were lower than those before surgery(P<0.05).There was no statistically significant difference in the Ramsay scores at different postoperative points of patients among the three groups(P>0.05).The incidence of adverse reactions 48 hours after surgery in the SK2 group was higher than those in the S group and the SK1 group(P<0.05).Conclusion Using 1 mg/kg of esketamine combined with 2 μg/kg of sufentanil after hip arthroplasty has a good analgesic effect without obvious increase of adverse reactions or significant effect on improving depression of patients.

Traumatic spinal cord injury (SCI) refers to damage to the structure and function of spinal cord caused by external trauma. This damage results in the loss of sensation, movement, or autonomous functions, which can lead to partial or complete paralysis and impact the patients’ independence and quality of life. Studying drugs related to spinal cord injuries and their mechanisms of action will help enhance patients’ quality of life and alleviate social and economic burdens. Traumatic spinal cord injury can be categorized into primary and secondary injuries. It leads to ongoing neurodegeneration, inflammation, and scarring, necessitating continuous intervention to reduce the cascading effects of secondary injuries. Regenerative repair of SCI has been one of the most challenging problems in medicine. It is characterized by the involvement of microglia, phagocytes (including neutrophils and monocytes), and antigen-presenting cells of the central nervous system, such as dendritic cells. These inflammatory mediators contribute to axonal demyelination and degeneration, leading to severe nerve damage. Currently, there has been little progress in the clinical treatment of SCI. Current clinical modalities, such as surgical interventions and hormone shock therapies, have not yielded specific pharmacotherapeutic options, hindering significant functional recovery. The current treatment methods are ineffective in alleviating oxidative stress and neuroinflammatory responses caused by spinal cord injury. They also do not offer neural protection, resulting in ongoing neurofunctional degradation. Intravenous injection of methylprednisolone through the arm has been used as a treatment option for spinal cord injury. Recent studies have shown that the potential side effects of the drug, such as blood clots and pneumonia, outweigh its benefits. Methylprednisolone is no longer recommended for the routine treatment of spinal cord injury. In recent years, significant progress has been made in spinal cord injury intervention through the use of nanotechnology and biomaterials. Nanozymes can enhance the therapeutic efficacy of spinal cord injury by catalyzing the clearance of free radicals similar to enzymes and suppressing inflammatory responses. Nanozymes can reduce the degree of fibrosis, promote neuron survival and angiogenesis, and provide favorable conditions for tissue regeneration. Through in vitro and in vivo toxicology experiments, it was found that the nanozyme demonstrates good biocompatibility and safety. It did not cause any significant changes in body weight, hematological indicators, or histopathology. These findings indicate the potential for its clinical applications. Based on current research results and discoveries, nanozymes have broad application prospects in the biomedical field. There are numerous potential research directions and application areas that are worthy of further exploration and development. Although there have been preliminary studies on the catalytic performance of nanozymes, further research is needed to thoroughly investigate their catalytic mechanisms. Further exploration of the interaction between nanozymes and substrates, reaction kinetics, and factors affecting catalytic activity will help to better understand their mechanism of action in the field of biocatalysis.

Objective:To analyze the influence of 5E rehabilitation mode on cardiac function,exercise capacity,self-man-agement ability and quality of life(QOL)in patients with coronary heart disease(CHD)after percutaneous coronary inter-vention(PCI).Methods:A total of 123 patients diagnosed with CHD in our hospital from April 1,2022 to April 1,2023 were selected and divided into control group(n=61,received routine nursing mode)and observation group(n=62,5E re-habilitation nursing mode was adopted on the basis of control group)using random number table method.Both groups were continuously intervened for three months.Cardiac function,exercise capacity,self-management level and QOL were compared between the two groups before and after intervention.Results:After intervention,compared with control group,there were significant rise in SV[(69.66±4.86)ml vs.(75.94±5.29)ml],CI[(3.11±0.30)L·min-1·m-2 vs.(3.39±0.36)L·min-1·m-2],LVEF[(57.22±5.82)％vs.(68.54±5.31)％],MET[(4.36±0.64)vs.(5.09±0.86)],6min walking distance[(296.52±18.72)m vs.(359.33±19.75)m],scores of CSMS[(89.32±11.85)points vs.(112.31±9.63)points],CQQC[(111.56±9.27)points vs.(139.50±7.59)points]in observation group,P=0.001 all;and significant reductions in LVEDd[(52.12±4.84)mm vs.(41.28±4.74)mm],LVESd[(48.39±3.82)mm vs.(42.26±3.57)mm],BNP level[(99.63±6.31)pg/ml vs.(60.52±7.11)pg/ml],propor-tion of NYHA class Ⅲ(25.00％vs.10.00％)in observation group,P＜0.05 or＜0.01.Conclusion:The application of 5E rehabilitation nursing can significantly improve cardiac function,enhance exercise capacity,strengthen the self-man-agement behavior and improve quality of life in postoperative clinical nursing of patients with coronary heart disease after percutaneous coronary intervention,which has high clinical application value.

Objective To analyze the changes of B lymphocyte(B cells)subsets in peripheral blood of patients with chronic hepatitis B(CHB)and to explore its clinical significance.Methods Peripheral blood samples were collected from 37 treatment-na?ve CHB patients who were admitted to the Fifth Medical Center of PLA General Hospital from July 2022 to October 2022,and peripheral blood samples collected from 18 healthy individuals who have received the hepatitis B vaccine as healthy controls(HC).The study subjects'clinical indexes such as age,HBV DNA viral load,HBsAg quantification,HBeAg semi quantification,ALT,AST,and AST/ALT ratio were collected.The change characteristics of the frequency,phenotypic and functional markers of peripheral blood B lymphocytes and their subsets were compared between CHB and HC.Using multi-color flow cytometry,and the correlation between them and clinical indexes was analyzed.Results Frequency analysis of each subset of B cells showed that compared with HC,the frequency of total B cells,transitional B cells and naive B cells was decreased(P<0.05),while the frequency of mature B cells,memory B cells,atypical memory B cells and activated memory B cells was increased in CHB patients(P<0.01).And there was no significant difference in the frequency of resting memory B cells between the two groups(P>0.05).The results of functional analysis showed that compared with HC,the expression levels of CD79b on total B cells,mature B cells,memory B cells,naive B cells,activated memory B cells,atypical memory B cells and resting memory B cells in CHB patients were increased(P<0.05).The expression level of programmed cell death protein-1(PD-1)on atypical memory B cells in CHB patients was also higher than that in HC group(P<0.05).The results of correlation analysis showed that the frequency of total B cells in CHB patients was slightly negatively correlated with age(r=-0.39,P<0.05),while the expression of programmed death-1(PD-1)on total B cells,mature B cells,transitional B cells,memory B cells and naive B cells were slightly positively correlated with age(r>0.36,P<0.05).Conclusions Chronic HBV infection leads to depletion of the frequency and function of a portion of B cells in the peripheral blood of CHB patients,and age is a potential risk factor for the decline in humoral immune function in CHB patients.

Objective To study the in vitro expression of three phenylalanine hydroxylase(PAH)mutants(p.R243Q,p.R241C,and p.Y356X)and determine their pathogenicity.Methods Bioinformatics techniques were used to predict the impact of PAH mutants on the structure and function of PAH protein.Corresponding mutant plasmids of PAH were constructed and expressed in HEK293T cells.Quantitative reverse transcription polymerase chain reaction was used to measure the mRNA expression levels of the three PAH mutants,and their protein levels were assessed using Western blot and enzyme-linked immunosorbent assay.Results Bioinformatics analysis predicted that all three mutants were pathogenic.The mRNA expression levels of the p.R243Q and p.R241C mutants in HEK293T cells were similar to the mRNA expression level of the wild-type control(P>0.05),while the mRNA expression level of the p.Y356X mutant significantly decreased(P<0.05).The PAH protein expression levels of all three mutants were significantly reduced compared to the wild-type control(P<0.05).The extracellular concentration of PAH protein was reduced in the p.R241C and p.Y356X mutants compared to the wild-type control(P<0.05),while there was no significant difference between the p.R243Q mutant and the wild type control(P>0.05).Conclusions p.R243Q,p.R241C and p.Y356X mutants lead to reduced expression levels of PAH protein in eukaryotic cells,with p.R241C and p.Y356X mutants also affecting the function of PAH protein.These three PAH mutants are to be pathogenic.[Chinese Journal of Contemporary Pediatrics,2024,26(2):188-193]

Objective To explore the effectiveness of different intervention strategies in response to outbreaks of emerging highly pathogenic respiratory infectious diseases(RIDs)in mega-city in China,and provide decision-ma-king basis for effective response to emerging RIDs.Methods A susceptible-exposed-infectious-recovered(SEIR)transmission dynamics model was constructed,referencing to and combining the pathogenicity and infectivity para-meters of previous emerging RIDs.The outbreak of emerging highly pathogenic RIDs with low,moderate,and high infectivity in a mega-city with a population of 10 million in China was simulated,the development of the epidemic within 100 days after implementing different combinations of non-pharmaceutical interventions(NPIs)in response to the outbreak was compared.Results When highly pathogenic RIDs outbreak occurred,and if its infectivity was low(R0 was about 1.5),it was unnecessary to adopt strict NPIs to control epidemic.If its infectivity was moderate(R0 was about 6),different intensities of NPIs were needed based on its existing infection scale.When the initial num-ber of infected cases was 50,moderate-intensity NPIs could keep the infection and death at a low level within 100 days,and the required bed number in hospital for cases could be kept below the national average reserve level.But when the scale of infection exceeded 100 cases,high-intensity NPIs were needed to control the development of the epidemic.In the case of extremely strong infectivity(R0 was about 10),regardless of the scale of infection,only immediate high-intensity NPIs could control the epidemic,infection and death scale.Conclusion In case of out-breaks of highly pathogenic RIDs,adopting appropriate NPIs as early as possible based on their epidemiological characteristics and infection scale is necessary to minimize the harm to the population.

Coronary perforation is when a contrast agent or blood flows outside a blood vessel through a tear in a coronary artery.In this case,we reported a case of percutaneous coronary intervention for coronary calcified lesions,which led to iatrogenic coronary perforation and cardiac tamponade after the use of Shockwave balloon to treat intracoronary calcified nodules,and the management of PCI-related CAP was systematically reviewed through the literature.

Objective To monitor the susceptibility of clinical isolates to antimicrobial agents in tertiary hospitals in major regions of China in 2022.Methods Clinical isolates from 58 hospitals in China were tested for antimicrobial susceptibility using a unified protocol based on disc diffusion method or automated testing systems.Results were interpreted using the 2022 Clinical &Laboratory Standards Institute(CLSI)breakpoints.Results A total of 318 013 clinical isolates were collected from January 1,2022 to December 31,2022,of which 29.5％were gram-positive and 70.5％were gram-negative.The prevalence of methicillin-resistant strains in Staphylococcus aureus,Staphylococcus epidermidis and other coagulase-negative Staphylococcus species(excluding Staphylococcus pseudintermedius and Staphylococcus schleiferi)was 28.3％,76.7％and 77.9％,respectively.Overall,94.0％of MRSA strains were susceptible to trimethoprim-sulfamethoxazole and 90.8％of MRSE strains were susceptible to rifampicin.No vancomycin-resistant strains were found.Enterococcus faecalis showed significantly lower resistance rates to most antimicrobial agents tested than Enterococcus faecium.A few vancomycin-resistant strains were identified in both E.faecalis and E.faecium.The prevalence of penicillin-susceptible Streptococcus pneumoniae was 94.2％in the isolates from children and 95.7％in the isolates from adults.The resistance rate to carbapenems was lower than 13.1％in most Enterobacterales species except for Klebsiella,21.7％-23.1％of which were resistant to carbapenems.Most Enterobacterales isolates were highly susceptible to tigecycline,colistin and polymyxin B,with resistance rates ranging from 0.1％to 13.3％.The prevalence of meropenem-resistant strains decreased from 23.5％in 2019 to 18.0％in 2022 in Pseudomonas aeruginosa,and decreased from 79.0％in 2019 to 72.5％in 2022 in Acinetobacter baumannii.Conclusions The resistance of clinical isolates to the commonly used antimicrobial agents is still increasing in tertiary hospitals.However,the prevalence of important carbapenem-resistant organisms such as carbapenem-resistant K.pneumoniae,P.aeruginosa,and A.baumannii showed a downward trend in recent years.This finding suggests that the strategy of combining antimicrobial resistance surveillance with multidisciplinary concerted action works well in curbing the spread of resistant bacteria.