Compared with total knee arthroplasty, unicondylar knee replacement has the advantage of preserving the knee tissue structure and motor function to the greatest extent. Pre-clinical in-vitro test is an important tool to evaluate the safety and effectiveness of unicondylar knee prostheses, and it is also a key focus of the product registration process. Through collection, comparison, and analysis of current regulations, technical standards, guidelines, and related research literature, this paper expounds on the relevant research methods for the pre-clinical in-vitrotesting of unicondylar knee prostheses. At the same time, in conjunction with current evaluation requirements and experience, the study discusses the focus of pre-clinical performance research for unicondylar knee prostheses during the registration process to clarify the performance evaluation requirements of this product category. This aims to provide a reference for the pre-clinical performance research of unicondylar knee prostheses and to standardize industry testing standards.
Knee Prosthesis ; Arthroplasty, Replacement, Knee ; Humans ; Prosthesis Design ; Materials Testing

Objective To investigate the distribution and antimicrobial resistance profiles of common pathogens isolated from cerebrospinal fluid(CSF)in CHINET program from 2015 to 2021.Methods The bacterial strains isolated from CSF were identified in accordance with clinical microbiology practice standards.Antimicrobial susceptibility test was conducted using Kirby-Bauer method and automated systems per the unified CHINET protocol.Results A total of 14 014 bacterial strains were isolated from CSF samples from 2015 to 2021,including the strains isolated from inpatients(95.3％)and from outpatient and emergency care patients(4.7％).Overall,19.6％of the isolates were from children and 80.4％were from adults.Gram-positive and Gram-negative bacteria accounted for 68.0％and 32.0％,respectively.Coagulase negative Staphylococcus accounted for 73.0％of the total Gram-positive bacterial isolates.The prevalence of MRSA was 38.2％in children and 45.6％in adults.The prevalence of MRCNS was 67.6％in adults and 69.5％in children.A small number of vancomycin-resistant Enterococcus faecium(2.2％)and linezolid-resistant Enterococcus faecalis(3.1％)were isolated from adult patients.The resistance rates of Escherichia coli and Klebsiella pneumoniae to ceftriaxone were 52.2％and 76.4％in children,70.5％and 63.5％in adults.The prevalence of carbapenem-resistant E.coli and K.pneumoniae(CRKP)was 1.3％and 47.7％in children,6.4％and 47.9％in adults.The prevalence of carbapenem-resistant Acinetobacter baumannii(CRAB)and Pseudomonas aeruginosa(CRPA)was 74.0％and 37.1％in children,81.7％and 39.9％in adults.Conclusions The data derived from antimicrobial resistance surveillance are crucial for clinicians to make evidence-based decisions regarding antibiotic therapy.Attention should be paid to the Gram-negative bacteria,especially CRKP and CRAB in central nervous system(CNS)infections.Ongoing antimicrobial resistance surveillance is helpful for optimizing antibiotic use in CNS infections.

Objective To investigate the antimicrobial resistance of clinical isolates from elderly patients(≥65 years)in major medical institutions across China.Methods Bacterial strains were isolated from elderly patients in 52 hospitals participating in the CHINET Antimicrobial Resistance Surveillance Program during the period from 2015 to 2021.Antimicrobial susceptibility test was carried out by disk diffusion method and automated systems according to the same CHINET protocol.The data were interpreted in accordance with the breakpoints recommended by the Clinical and Laboratory Standards Institute(CLSI)in 2021.Results A total of 514 715 nonduplicate clinical isolates were collected from elderly patients in 52 hospitals from January 1,2015 to December 31,2021.The number of isolates accounted for 34.3％of the total number of clinical isolates from all patients.Overall,21.8％of the 514 715 strains were gram-positive bacteria,and 78.2％were gram-negative bacteria.Majority(90.9％)of the strains were isolated from inpatients.About 42.9％of the strains were isolated from respiratory specimens,and 22.9％were isolated from urine.More than half(60.7％)of the strains were isolated from male patients,and 39.3％isolated from females.About 51.1％of the strains were isolated from patients aged 65-＜75 years.The prevalence of methicillin-resistant strains(MRSA)was 38.8％in 32 190 strains of Staphylococcus aureus.No vancomycin-or linezolid-resistant strains were found.The resistance rate of E.faecalis to most antibiotics was significantly lower than that of Enterococcus faecium,but a few vancomycin-resistant strains(0.2％,1.5％)and linezolid-resistant strains(3.4％,0.3％)were found in E.faecalis and E.faecium.The prevalence of penicillin-susceptible S.pneumoniae(PSSP),penicillin-intermediate S.pneumoniae(PISP),and penicillin-resistant S.pneumoniae(PRSP)was 94.3％,4.0％,and 1.7％in nonmeningitis S.pneumoniae isolates.The resistance rates of Klebsiella spp.(Klebsiella pneumoniae 93.2％)to imipenem and meropenem were 20.9％and 22.3％,respectively.Other Enterobacterales species were highly sensitive to carbapenem antibiotics.Only 1.7％-7.8％of other Enterobacterales strains were resistant to carbapenems.The resistance rates of Acinetobacter spp.(Acinetobacter baumannii 90.6％)to imipenem and meropenem were 68.4％and 70.6％respectively,while 28.5％and 24.3％of P.aeruginosa strains were resistant to imipenem and meropenem,respectively.Conclusions The number of clinical isolates from elderly patients is increasing year by year,especially in the 65-＜75 age group.Respiratory tract isolates were more prevalent in male elderly patients,and urinary tract isolates were more prevalent in female elderly patients.Klebsiella isolates were increasingly resistant to multiple antimicrobial agents,especially carbapenems.Antimicrobial resistance surveillance is helpful for accurate empirical antimicrobial therapy in elderly patients.

Objective To summarize the changing prevalence of carbapenem resistance in Enterobacterales based on the data of CHINET Antimicrobial Resistance Surveillance Program from 2015 to 2021 for improving antimicrobial treatment in clinical practice.Methods Antimicrobial susceptibility testing was performed using a commercial automated susceptibility testing system according to the unified CHINET protocol.The results were interpreted according to the breakpoints of the Clinical & Laboratory Standards Institute(CLSI)M100 31st ed in 2021.Results Over the seven-year period(2015-2021),the overall prevalence of carbapenem-resistant Enterobacterales(CRE)was 9.43％(62 342/661 235).The prevalence of CRE strains in Klebsiella pneumoniae,Citrobacter freundii,and Enterobacter cloacae was 22.38％,9.73％,and 8.47％,respectively.The prevalence of CRE strains in Escherichia coli was 1.99％.A few CRE strains were also identified in Salmonella and Shigella.The CRE strains were mainly isolated from respiratory specimens(44.23±2.80)％,followed by blood(20.88±3.40)％and urine(18.40±3.45)％.Intensive care units(ICUs)were the major source of the CRE strains(27.43±5.20)％.CRE strains were resistant to all the β-lactam antibiotics tested and most non-β-lactam antimicrobial agents.The CRE strains were relatively susceptible to tigecycline and polymyxins with low resistance rates.Conclusions The prevalence of CRE strains was increasing from 2015 to 2021.CRE strains were highly resistant to most of the antibacterial drugs used in clinical practice.Clinicians should prescribe antimicrobial agents rationally.Hospitals should strengthen antibiotic stewardship in key clinical settings such as ICUs,and take effective infection control measures to curb CRE outbreak and epidemic in hospitals.

Objective To characterize the changing species distribution and antibiotic resistance profiles of respiratory isolates in hospitals participating in the CHINET Antimicrobial Resistance Surveillance Program from 2015 to 2021.Methods Commercial automated antimicrobial susceptibility testing systems and disk diffusion method were used to test the susceptibility of respiratory bacterial isolates to antimicrobial agents following the standardized technical protocol established by the CHINET program.Results A total of 589 746 respiratory isolates were collected from 2015 to 2021.Overall,82.6％of the isolates were Gram-negative bacteria and 17.4％were Gram-positive bacteria.The bacterial isolates from outpatients and inpatients accounted for(6.0±0.9)％and(94.0±0.1)％,respectively.The top microorganisms were Klebsiella spp.,Acinetobacter spp.,Pseudomonas aeruginosa,Staphylococcus aureus,Haemophilus spp.,Stenotrophomonas maltophilia,Escherichia coli,and Streptococcus pneumoniae.Each microorganism was isolated from significantly more males than from females(P＜0.05).The overall prevalence of methicillin-resistant S.aureus(MRSA)was 39.9％.The prevalence of penicillin-resistant S.pneumoniae was 1.4％.The prevalence of extended-spectrum β-lactamase(ESBL)-producing E.coli and K.pneumoniae was 67.8％and 41.3％,respectively.The overall prevalence of carbapenem-resistant E.coli,K.pneumoniae,Enterobacter cloacae,Pseudomonas aeruginosa,and Acinetobacter baumannii was 3.7％,20.8％,9.4％,29.8％,and 73.3％,respectively.The prevalence of β-lactamase was 96.1％in Moraxella catarrhalis and 60.0％in Haemophilus influenzae.The H.influenzae isolates from children(＜18 years)showed significantly higher resistance rates to β-lactam antibiotics than the isolates from adults(P＜0.05).Conclusions Gram-negative bacteria are still predominant in respiratory isolates associated with serious antibiotic resistance.Antimicrobial resistance surveillance should be strengthened in clinical practice to support accurate etiological diagnosis and appropriate antimicrobial therapy based on antimicrobial susceptibility testing results.

Purpose: This study aimed to adapt the Nurses Professional Values Scale-3 (NPVS-3) for Korean nursing students and assess its reliability and validity. Methods: The NPVS-3 was translated into Korean using forward and back translation with expert review. Data from 206 nursing students at four universities were analyzed to assess content, construct, discriminant, and criterion validity, as well as internal consistency. Results: The Korean version (NPVS-3K) consisted of 21 items in three subscales: caring (eight items), activism (eight items), and professionalism (five items), explaining 60.9% of the total variance. For convergent validity, standardized coefficients for the items ranged from .56 to .81, construct reliability ranged from .89 to .95, and the average variance extracted ranged from .61 to .72. The model was validated by confirmatory factor analysis (χ2=526.00 [p<.001], χ2/degrees of freedom=2.83, standardized root mean residual=.03, goodness of fit index=.81, comparative fit index=.87, Turker Lewis index=.85). Discriminant validity was confirmed using a multi-trait and multi-item matrix. Criterion validity showed positive correlations between the three NPVS-3K factors and professional identity (factor 1: r=.40, p<.001; factor 2: r=.55, p<.001; factor 3: r=.43, p<.001). Internal consistency, as measured by Cronbach’s α, was .94 overall, with subscale values of .90 for caring, .92 for activism, and .78 for professionalism. Conclusion The NPVS-3K demonstrated satisfactory validity and reliability, establishing it as a valuable tool for assessing the professional values of Korean nursing students. Additionally, it can aid in developing educational strategies to strengthen these values, although further research is required to confirm its broader applicability.

Purpose: This study aimed to assess the impact of aerobic exercise at different intensities over an eight-week period on the expression and activation of cortical synaptic proteins, with the potential to reduce anxiety and improve memory in young mice. Methods: Seven-week-old C57BL/6 mice were subjected to treadmill exercises at low (n = 10), moderate (n = 10), and high intensity (n = 10) for eight weeks. Behavioral assessments were conducted to evaluate anxiety and cognitive function. To explore the underlying mechanisms, we measured the phosphorylated levels of extracellular signal-regulated kinase (ERK), cyclic adenosine monophosphate response-binding protein (CREB), protein kinase (AKT), adenosine monophosphate activated protein kinase (AMPK), synapsin (S9, S549, S609), and PSD-95 in the cortex, as these are associated with synaptic strength. Additionally, the expression of doublecortin (DCX), a neurogenic factor, was analyzed in the hippocampus. Results: Exercise led to reductions in depressive and anxiety-related behaviors and elevated the levels of phosphorylated ERK, CREB, AKT, AMPK, synapsin (S9, S549, S609), and PSD-95 in the cortex of young mice. Furthermore, exercise increased DCX expression in the hippocampus. Moderate-intensity exercise yielded more pronounced effects than other intensities. Conclusion The findings of this research indicate that consistent moderate-intensity exercise increases synaptic strength and reduces depression and anxiety in young mice by activating multiple factors.

Purpose: This study aimed to adapt the Nurses Professional Values Scale-3 (NPVS-3) for Korean nursing students and assess its reliability and validity. Methods: The NPVS-3 was translated into Korean using forward and back translation with expert review. Data from 206 nursing students at four universities were analyzed to assess content, construct, discriminant, and criterion validity, as well as internal consistency. Results: The Korean version (NPVS-3K) consisted of 21 items in three subscales: caring (eight items), activism (eight items), and professionalism (five items), explaining 60.9% of the total variance. For convergent validity, standardized coefficients for the items ranged from .56 to .81, construct reliability ranged from .89 to .95, and the average variance extracted ranged from .61 to .72. The model was validated by confirmatory factor analysis (χ2=526.00 [p<.001], χ2/degrees of freedom=2.83, standardized root mean residual=.03, goodness of fit index=.81, comparative fit index=.87, Turker Lewis index=.85). Discriminant validity was confirmed using a multi-trait and multi-item matrix. Criterion validity showed positive correlations between the three NPVS-3K factors and professional identity (factor 1: r=.40, p<.001; factor 2: r=.55, p<.001; factor 3: r=.43, p<.001). Internal consistency, as measured by Cronbach’s α, was .94 overall, with subscale values of .90 for caring, .92 for activism, and .78 for professionalism. Conclusion The NPVS-3K demonstrated satisfactory validity and reliability, establishing it as a valuable tool for assessing the professional values of Korean nursing students. Additionally, it can aid in developing educational strategies to strengthen these values, although further research is required to confirm its broader applicability.

Purpose: This study aimed to assess the impact of aerobic exercise at different intensities over an eight-week period on the expression and activation of cortical synaptic proteins, with the potential to reduce anxiety and improve memory in young mice. Methods: Seven-week-old C57BL/6 mice were subjected to treadmill exercises at low (n = 10), moderate (n = 10), and high intensity (n = 10) for eight weeks. Behavioral assessments were conducted to evaluate anxiety and cognitive function. To explore the underlying mechanisms, we measured the phosphorylated levels of extracellular signal-regulated kinase (ERK), cyclic adenosine monophosphate response-binding protein (CREB), protein kinase (AKT), adenosine monophosphate activated protein kinase (AMPK), synapsin (S9, S549, S609), and PSD-95 in the cortex, as these are associated with synaptic strength. Additionally, the expression of doublecortin (DCX), a neurogenic factor, was analyzed in the hippocampus. Results: Exercise led to reductions in depressive and anxiety-related behaviors and elevated the levels of phosphorylated ERK, CREB, AKT, AMPK, synapsin (S9, S549, S609), and PSD-95 in the cortex of young mice. Furthermore, exercise increased DCX expression in the hippocampus. Moderate-intensity exercise yielded more pronounced effects than other intensities. Conclusion The findings of this research indicate that consistent moderate-intensity exercise increases synaptic strength and reduces depression and anxiety in young mice by activating multiple factors.

Purpose: This study aimed to adapt the Nurses Professional Values Scale-3 (NPVS-3) for Korean nursing students and assess its reliability and validity. Methods: The NPVS-3 was translated into Korean using forward and back translation with expert review. Data from 206 nursing students at four universities were analyzed to assess content, construct, discriminant, and criterion validity, as well as internal consistency. Results: The Korean version (NPVS-3K) consisted of 21 items in three subscales: caring (eight items), activism (eight items), and professionalism (five items), explaining 60.9% of the total variance. For convergent validity, standardized coefficients for the items ranged from .56 to .81, construct reliability ranged from .89 to .95, and the average variance extracted ranged from .61 to .72. The model was validated by confirmatory factor analysis (χ2=526.00 [p<.001], χ2/degrees of freedom=2.83, standardized root mean residual=.03, goodness of fit index=.81, comparative fit index=.87, Turker Lewis index=.85). Discriminant validity was confirmed using a multi-trait and multi-item matrix. Criterion validity showed positive correlations between the three NPVS-3K factors and professional identity (factor 1: r=.40, p<.001; factor 2: r=.55, p<.001; factor 3: r=.43, p<.001). Internal consistency, as measured by Cronbach’s α, was .94 overall, with subscale values of .90 for caring, .92 for activism, and .78 for professionalism. Conclusion The NPVS-3K demonstrated satisfactory validity and reliability, establishing it as a valuable tool for assessing the professional values of Korean nursing students. Additionally, it can aid in developing educational strategies to strengthen these values, although further research is required to confirm its broader applicability.