OBJECTIVE: To evaluate the effects of posterior cruciate ligament(PCL) resection on soft tissue elasticity and knee stability in total knee arthroplasty(TKA). METHODS: Six adult cadaveric knee specimens (involving 10 knees) were included in the study. With the assistance of the robotic system(TiRobot Recon, TINAVI, Beijing), total knee arthroplasty (TKA) was performed sequentially using cruciate retaining (CR) prostheses and posterior stabilizing (PS) prostheses. Between the two surgical procedures, the femoral and tibial osteotomy surfaces were not altered;only the posterior cruciate ligament (PCL) was resected and the intercondylar fossa was treated. After installing the femoral trial component, a soft tissue balance solver was used to apply tension ranging from 30 N to 90 N in 5 N increments at 0°, 10°, and 90° of knee flexion. Meanwhile, the medial and lateral joint gaps were measured synchronously. Based on the tension-gap coupling data, the equivalent elastic coefficients of the medial and lateral soft tissue sleeves at different knee flexion angles, as well as the range of the joint line convergence angle (JLCA) under fixed varus-valgus stress, were calculated. Additionally, the gap balance status under 80 N of tension was analyzed. Self-control comparisons of each indicator were conducted before and after PCL resection to analyze the change patterns. RESULTS: After PCL resection, in the fully extended position (knee flexion 0°). The medial equivalent elastic coefficient was 32.2 (25.7, 63.3) N·mm^-1 for the CR prosthesis and 27.7 (22.0, 51.9) N·mm^-1 for the PS prosthesis, and the statistically significant difference (P=0.013). The range of JLCA was 0.41°(0.26, 0.55)° for the CR prosthesis, which was smaller than 0.75° (0.40, 0.98)° for the PS prosthesis, and the difference was statistically significant(P=0.041). At 90° of knee flexion, the medial joint gap was 10.7(10.1, 11.7) mm for the CR prosthesis, which was smaller than 12.1(10.9, 15.1) mm for the PS prosthesis, with a statistically significant difference(P=0.011). No statistically significant differences were observed in other joint gaps. CONCLUSION PCL resection reduces the rigidity of the medial soft tissues in the fully extended knee and increases the medial joint gap in the flexed position, thereby affecting knee stability and balance. This finding suggests that PS and CR prostheses may require different morphological designs, and there should be differences in indications and osteotomy strategies between CR-TKA and PS-TKA. CR-TKA is more suitable for patients with preoperative medial soft tissue laxity.
Humans ; Posterior Cruciate Ligament/physiopathology* ; Knee Joint/physiopathology* ; Arthroplasty, Replacement, Knee ; Elasticity ; Male ; Female ; Middle Aged ; Aged ; Biomechanical Phenomena ; Adult

This study was aimed at understanding the resistance status of dairy cow-derived Streptococcus strains in China,and providing scientific guidance for the rational use of antimicrobials and the development of new antimicrobials.Meta-analysis was used to explore the resistance of Streptococcus strains to 20 antimicrobials between 2000 and 2023.A total of 67 articles de-scribing 3 154 strains were included after a literature search,and a meta-analysis was conducted on the overall collection area according to time subgroups for 20 antimicrobials.Streptococci of dairy origin in China showed varying resistance rates(≥30％),as follows:penicillin(60％,95％CI=0.48-0.72),streptomycin(57％,95％CI=0.46-0.68),cotrimoxazole(56％,95％CI=0.28-0.82),lincomycin(51％,95％CI=0.26-0.76),tetracycline(49％,95％CI=0.40-0.59),doxycyc-line(42％,95％CI=0.24-0.60),clindamycin(41％,95％CI=0.28-0.54),ampicillin(39％,95％CI=0.27-0.52),e-rythromycin(37％,95％CI=0.28-0.45),kanamycin(36％,95％CI=0.20-0.54),and amoxicillin(30％,95％CI=0.10-0.53).On the basis of findings in the collection area,the resistance rates of dairy cow-derived Streptococcus to antimicrobials in Northeast China and Southwest China was generally high.The resistance rates of Streptococcus from dairy cattle to antimi-crobial drugs such as tetracycline,doxycycline,and lincomycin increased significantly over time.However,the resistance rates to antimicrobial drugs such as streptomycin,gentamicin,and enrofloxacin showed a significant decreasing trend.Dairy cow-de-rived Streptococcus had high resistance to some antimicrobials,and the resistance varied by region,because of differences in breeding and management.Monitoring of antimicrobial resistance rates,enhancing research on resistance mechanisms,and reg-ulating the use of antimicrobials remain necessary.

AIM To establish LC-MS and GC-MS method and analyze the chemical constituents of Dendrobium huoshanense C.Z.Tang & S.J.Cheng flowers.METHODS LC-MS was performed on a Zorbax Eclipse C18 column(2.1 mm×100 mm,1.8 μm),with the mobile phase comprising of water(containing 0.1％formic acid)-acetonitrile flowing at 0.3 mL/min,and electrospray ionization was operated in both positive and negative ion modes.The GC-MS employed headspace solid-phase microextraction for sample preparation,and the analysis was performed on an HP-5MS column(30 m×0.25 mm,0.25 μm),with the following temperature program:initial temperature 50 ℃(held for 2 min),increased at 5 ℃/min to 180 ℃(held for 5 min),then raised at 10 ℃/min to 250 ℃(held for 5 min),and electron impact ion source was employed.RESULTS A total of 62 compounds were identified by LC-MS,including 35 flavonoids,4 coumarins,6 alkaloids,6 terpenoids,3 amino acids,2 polyphenols,2 ketones and 4 others.A total of 101 volatile components were identified by GC-MS,including ketones,aldehydes,alcohols,esters,ethers,and acid.CONCLUSION This method can comprehensively analyze the chemical constituents of D.huoshanense flowers,and provide a scientific basis for elucidating its pharmacodynamic material basis.

Oral squamous cell carcinoma (OSCC) is the most common head and neck malignancy worldwide, accounting for more than 90% of all oral cancers, and is characterized by high invasiveness and poor long-term prognosis. Its etiology is multifactorial, involving tobacco use, alcohol consumption, and human papillomavirus (HPV) infection. Oral leukoplakia and erythroplakia are the main precancerous lesions lesions, with oral leukoplakia being the most common. Both OSCC and premalignant lesions are closely associated with aberrant activation of multiple signaling pathways. Post-translational modifications (such as ubiquitination and deubiquitination) play key roles in regulating these pathways by controlling protein stability and activity. Growing evidence indicates that dysregulated ubiquitination/deubiquitination can mediate OSCC initiation and progression via aberrant activation of signaling pathways. The ubiquitination/deubiquitination process mainly involves E3 ligases (E3s) that catalyze substrate ubiquitination, deubiquitinating enzymes (DUBs) that remove ubiquitin chains, and the 26S proteasome complex that degrades ubiquitinated substrates. Abnormal expression or mutation of E3s and DUBs can lead to altered stability of critical tumor-related proteins, thereby driving OSCC initiation and progression. Therefore, understanding the aberrantly activated signaling pathways in OSCC and the ubiquitination/deubiquitination mechanisms within these pathways will help elucidate the molecular mechanisms and improve OSCC treatment by targeting relevant components. Here, we summarize four aberrantly activated signaling pathways in OSCC―the PI3K/AKT/mTOR pathway, Wnt/β-catenin pathway, Hippo pathway, and canonical NF-κB pathway―and systematically review the regulatory mechanisms of ubiquitination/deubiquitination within these pathways, along with potential drug targets. PI3K/AKT/mTOR pathway is aberrantly activated in approximately 70% of OSCC cases. It is modulated by E3s (e.g., FBXW7 and NEDD4) and DUBs (e.g., USP7 and USP10): FBXW7 and USP10 inhibit signaling, while NEDD4 and USP7 potentiate it. Aberrant activation of the Wnt/β‑catenin pathway leads to β‑catenin nuclear translocation and induction of cell proliferation. This pathway is modulated by E3s (e.g., c-Cbl and RNF43) and DUBs (e.g., USP9X and USP20): c-Cbl and RNF43 inhibit signaling, while USP9X and USP20 potentiate it. Hippo pathway inactivation permits YAP/TAZ to enter the nucleus and promotes cancer cell metastasis. This pathway is modulated by E3s (e.g., CRL4^DCAF1 and SIAH2) and DUBs (e.g., USP1 and USP21): CRL4^DCAF1 and SIAH2 inhibit signaling, while USP1 and USP21 potentiate it. Persistent activation of the canonical NF-κB pathway is associated with an inflammatory microenvironment and chemotherapy resistance. This pathway is modulated by E3s (e.g., TRAF6 and LUBAC) and DUBs (e.g., A20 and CYLD): A20 and CYLD inhibit signaling, while TRAF6 and LUBAC potentiate it. Targeting these E3s and DUBs provides directions for OSCC drug research. Small-molecule inhibitors such as YCH2823 (a USP7 inhibitor), GSK2643943A (a USP20 inhibitor), and HOIPIN-8 (a LUBAC inhibitor) have shown promising antitumor activity in preclinical models; PROTAC molecules, by binding to surface sites of target proteins and recruiting E3s, achieve targeted ubiquitination and degradation of proteins insensitive to small-molecule inhibitors, for example, PU7-1-mediated USP7 degradation, offering new strategies to overcome traditional drug limitations. Currently, NX-1607 (a Cbl-b inhibitor) has entered phase I clinical trials, with preliminary results confirming its safety and antitumor activity. Future research on aberrant E3s and DUBs in OSCC and the development of highly specific inhibitors will be of great significance for OSCC precision therapy.

Objective To explore the possibility and genetic identification method of constructing a hepatocyte-specific NLRP3 gene knockout mouse model by using Cre-LoxP system gene knockout technology.Methods Phase one:mice specifically expressing the albumin promoter-Cre(AlbCre)recombinase in hepatocytes were mated with NLRP3flox/flox mice,and the hepatocyte-specific NLRP3 gene knockout mice with the genotype of NLRP3flox/flox/AlbCre+/-(hepatocyte NLRP3 knockout group)and the control mice in the same litter with the genotype of NLRP3flox/flox/AlbCre-/-(control group in the same litter)were obtained after two generations of selection and mating.The second stage was the mass reproduction stage.Mating NLRP3flox/flox/AlbCre+/-target mice with NLRP3flox/flox mice could quickly obtain a large number of experimental target mice and control mice in the same litter.The DNA was extracted from the tails of mice after numbering,and the offspring genotype was identified by PCR.qPCR and Western blot were used to detect the mRNA and protein expression levels of NLRP3 gene in the liver tissue.HE staining was used to observe the morphological changes in liver tissues,and serum liver transaminases and inflammatory factors were detected.The changes in body weight,liver-to-body ratio and special circumstances during reproduction and development of mice in the two groups were observed.Results The offspring genotype of the target mice in the F2 generation was consistent with theoretical result of NLRP3flox/flox/AlbCre+/-.The mRNA and protein levels of NLRP3 in liver tissues of mice in the hepatocyte NLRP3 knockout group were significantly lower than those in the control group in the same litter(P<0.05).The mice in the hepatocyte NLRP3 knockout group was not affected in terms of growth,development and reproduction after the NLRP3 gene knockout.There were no statistically significant differences in the body weight,liver-to-body ratio,liver tissue morphology,serum liver transaminase or inflammatory factors between the hepatocyte NLRP3 knockout group and the control group in the same litter(P>0.05).Conclusion The Cre-LoxP gene knockout technology can be used to successfully construct a hepatocyte-specific NLRP3 gene knockout mouse model,providing an important technical support for the next step of studying the function of the NLRP3 gene in the liver at the animal level.

Aim To explore the therapeutic effect of Shenwuyishen tablets(SWYST)in treating chronic kidney disease(CKD)and the underlying mechanism.Methods The pharmacological action of SWYST was evaluated in folic acid(FA)-induced mouse models by levels of serum creatinine and blood urea nitrogen,in-dexes of tubulointerstitial inflammation and tubular in-jury,and degrees of renal fibrosis.Differential genes from 22 types of cells in kidney tissue of CKD were i-dentified by single-cell and single-nuclei RNA sequen-cing datasets.Network pharmacology was used to pre-dict key ingredients,cells,and targets.The binding mode between the key ingredients and key targets was elucidated using molecular docking and molecular dy-namics simulation.Results Serum creatinine and blood urea nitrogen levels,tubulointerstitial inflamma-tion and tubular injury indexes,and renal fibrosis de-grees were significantly reduced by SWYST administra-tion.Quercetin,kaempferol,luteolin,baicalein and wogonin were considered as key components that main-ly acted through FOS and JUN of endothelial cells,neu-trophils and thick ascending limb cells to ameliorate CKD.Molecular docking and molecular dynamics sim-ulation revealed that quercetin stably occupied the cross pocket of FOS-JUN heterodimers to inhibit the binding between FOS-JUN heterodimers and DNA.Conclusion SWYST inhibits the binding of FOS-JUN heterodimers and DNA of endothelial cells,neutrophils and thick ascending limb cells to ameliorate CKD.

Aim To explore the therapeutic effect of Shenwuyishen tablets(SWYST)in treating chronic kidney disease(CKD)and the underlying mechanism.Methods The pharmacological action of SWYST was evaluated in folic acid(FA)-induced mouse models by levels of serum creatinine and blood urea nitrogen,in-dexes of tubulointerstitial inflammation and tubular in-jury,and degrees of renal fibrosis.Differential genes from 22 types of cells in kidney tissue of CKD were i-dentified by single-cell and single-nuclei RNA sequen-cing datasets.Network pharmacology was used to pre-dict key ingredients,cells,and targets.The binding mode between the key ingredients and key targets was elucidated using molecular docking and molecular dy-namics simulation.Results Serum creatinine and blood urea nitrogen levels,tubulointerstitial inflamma-tion and tubular injury indexes,and renal fibrosis de-grees were significantly reduced by SWYST administra-tion.Quercetin,kaempferol,luteolin,baicalein and wogonin were considered as key components that main-ly acted through FOS and JUN of endothelial cells,neu-trophils and thick ascending limb cells to ameliorate CKD.Molecular docking and molecular dynamics sim-ulation revealed that quercetin stably occupied the cross pocket of FOS-JUN heterodimers to inhibit the binding between FOS-JUN heterodimers and DNA.Conclusion SWYST inhibits the binding of FOS-JUN heterodimers and DNA of endothelial cells,neutrophils and thick ascending limb cells to ameliorate CKD.

This study was aimed at understanding the resistance status of dairy cow-derived Streptococcus strains in China,and providing scientific guidance for the rational use of antimicrobials and the development of new antimicrobials.Meta-analysis was used to explore the resistance of Streptococcus strains to 20 antimicrobials between 2000 and 2023.A total of 67 articles de-scribing 3 154 strains were included after a literature search,and a meta-analysis was conducted on the overall collection area according to time subgroups for 20 antimicrobials.Streptococci of dairy origin in China showed varying resistance rates(≥30％),as follows:penicillin(60％,95％CI=0.48-0.72),streptomycin(57％,95％CI=0.46-0.68),cotrimoxazole(56％,95％CI=0.28-0.82),lincomycin(51％,95％CI=0.26-0.76),tetracycline(49％,95％CI=0.40-0.59),doxycyc-line(42％,95％CI=0.24-0.60),clindamycin(41％,95％CI=0.28-0.54),ampicillin(39％,95％CI=0.27-0.52),e-rythromycin(37％,95％CI=0.28-0.45),kanamycin(36％,95％CI=0.20-0.54),and amoxicillin(30％,95％CI=0.10-0.53).On the basis of findings in the collection area,the resistance rates of dairy cow-derived Streptococcus to antimicrobials in Northeast China and Southwest China was generally high.The resistance rates of Streptococcus from dairy cattle to antimi-crobial drugs such as tetracycline,doxycycline,and lincomycin increased significantly over time.However,the resistance rates to antimicrobial drugs such as streptomycin,gentamicin,and enrofloxacin showed a significant decreasing trend.Dairy cow-de-rived Streptococcus had high resistance to some antimicrobials,and the resistance varied by region,because of differences in breeding and management.Monitoring of antimicrobial resistance rates,enhancing research on resistance mechanisms,and reg-ulating the use of antimicrobials remain necessary.

Objective To explore the possibility and genetic identification method of constructing a hepatocyte-specific NLRP3 gene knockout mouse model by using Cre-LoxP system gene knockout technology.Methods Phase one:mice specifically expressing the albumin promoter-Cre(AlbCre)recombinase in hepatocytes were mated with NLRP3flox/flox mice,and the hepatocyte-specific NLRP3 gene knockout mice with the genotype of NLRP3flox/flox/AlbCre+/-(hepatocyte NLRP3 knockout group)and the control mice in the same litter with the genotype of NLRP3flox/flox/AlbCre-/-(control group in the same litter)were obtained after two generations of selection and mating.The second stage was the mass reproduction stage.Mating NLRP3flox/flox/AlbCre+/-target mice with NLRP3flox/flox mice could quickly obtain a large number of experimental target mice and control mice in the same litter.The DNA was extracted from the tails of mice after numbering,and the offspring genotype was identified by PCR.qPCR and Western blot were used to detect the mRNA and protein expression levels of NLRP3 gene in the liver tissue.HE staining was used to observe the morphological changes in liver tissues,and serum liver transaminases and inflammatory factors were detected.The changes in body weight,liver-to-body ratio and special circumstances during reproduction and development of mice in the two groups were observed.Results The offspring genotype of the target mice in the F2 generation was consistent with theoretical result of NLRP3flox/flox/AlbCre+/-.The mRNA and protein levels of NLRP3 in liver tissues of mice in the hepatocyte NLRP3 knockout group were significantly lower than those in the control group in the same litter(P<0.05).The mice in the hepatocyte NLRP3 knockout group was not affected in terms of growth,development and reproduction after the NLRP3 gene knockout.There were no statistically significant differences in the body weight,liver-to-body ratio,liver tissue morphology,serum liver transaminase or inflammatory factors between the hepatocyte NLRP3 knockout group and the control group in the same litter(P>0.05).Conclusion The Cre-LoxP gene knockout technology can be used to successfully construct a hepatocyte-specific NLRP3 gene knockout mouse model,providing an important technical support for the next step of studying the function of the NLRP3 gene in the liver at the animal level.

AIM To establish LC-MS and GC-MS method and analyze the chemical constituents of Dendrobium huoshanense C.Z.Tang & S.J.Cheng flowers.METHODS LC-MS was performed on a Zorbax Eclipse C18 column(2.1 mm×100 mm,1.8 μm),with the mobile phase comprising of water(containing 0.1％formic acid)-acetonitrile flowing at 0.3 mL/min,and electrospray ionization was operated in both positive and negative ion modes.The GC-MS employed headspace solid-phase microextraction for sample preparation,and the analysis was performed on an HP-5MS column(30 m×0.25 mm,0.25 μm),with the following temperature program:initial temperature 50 ℃(held for 2 min),increased at 5 ℃/min to 180 ℃(held for 5 min),then raised at 10 ℃/min to 250 ℃(held for 5 min),and electron impact ion source was employed.RESULTS A total of 62 compounds were identified by LC-MS,including 35 flavonoids,4 coumarins,6 alkaloids,6 terpenoids,3 amino acids,2 polyphenols,2 ketones and 4 others.A total of 101 volatile components were identified by GC-MS,including ketones,aldehydes,alcohols,esters,ethers,and acid.CONCLUSION This method can comprehensively analyze the chemical constituents of D.huoshanense flowers,and provide a scientific basis for elucidating its pharmacodynamic material basis.