AIM To study the flavonoids from the leaves of Cinnamomum camphora(L.)Presl.and their antioxidant activities.METHODS The 95％ethanol extraction from the leaves of C.camphora was isolated and purified by liquid-liquid extraction,macroporous adsorption resin chromatography,HW-40C gel column chromatography,molecular exclusion chromatography and preparative HPLC,then the structures of obtained compounds were identified by physicochemical properties and spectral data.The antioxidant activity was determined by DPPH method.RESULT Ten flavonoids were isolated and identified as(2R,3S)-7-methoxy-5-O-β-D-glucopyranosyl-afzelechin(1),quercetin-3-O-sambubioside(2),quercetin-3-O-β-D-apiosyl-(1→2)-β-D-glucoside(3),quercetin-3-O-robibioside(4),kaempferol-3-O-β-D-rutinoside-7-O-β-D-glucoside(5),kaempferol-3-O-α-L-rhamnoside-7-O-β-D-glucoside(6),5,3'-di-O-methyl-epicatechin(7)、cinchonain Ⅱb(8)、quercetin-3,4'-di-O-β-D-glucoside(9)、(-)-epicatechin(10).The IC50 value of compound 8 scavenging DPPH free radical was 4.8 μg/mL.CONCLUSION Compound 1 is a new compound,and compound 2-6 are obtained from Cinnamomum genus for the first time,compound 7-9 are first isolated from this plant.Compound 8 shows good antioxidant activities..

Objective To analyze the stresses in implanted titanium solid and bone trabecular prosthesis hip replacements.Methods A femur model was built inversely based on Mimics software,and optimized using Geomagic software,and then materialized by SolidWorks software.The osteotomized femur was assembled with the metal femoral stem to form a model,and then the model was imported into ABAQUS for finite element calculation.The upper femur was divided into four regions in different states of integration:medial proximal point(small trochanter region),lateral proximal region(large trochanter region),proximal point of the femoral stem(region around the mid-portion of the styloid process)and distal region(around the end of the styloid process and distal portion).Calculations were carried out over the femoral stresses before and after implantation of titanium solid and trabecular prostheses under gait and stair-climbing loads and the interfacial stresses when the region was unintegrated.The type of deformation at the bone interface was analyzed by means of a stress ellipsoid.Results At the small trochanter region,the stress shielding rates of the trabecular prosthesis under gait and stair climbing loads were reduced by 20.5％and 14.7％compared to the titanium solid prosthesis,respectively.In case of different integration states of the titanium solid prosthesis,the interface tensile stresses under the gait and stair climbing loads were up to 10.842 MPa and 12.900 MPa,and the shear stresses reached 7.050 MPa and 6.805 MPa,respectively;in case of different integration states of the trabecular prosthesis,the interface tensile stresses under the gait and stair climbing loads were up to 3.858 MPa and 4.389 MPa,and the shear stresses reached 4.156 MPa and 3.854 MPa,respectively.Under the 2 different loads,the inboard shear stress ellipsoid of the interface opened toward the sides and the bone interface showed tensile deformation;the outboard shear stress ellipsoid of the interface opened up and down and had compressive deformation.Conclusion After total hip arthroplasty,the overall performance of the trabecular prosthesis is better than that of the titanium solid prosthesis.The unintegrated edges of the prosthesis-bone interface are susceptible to stress concentrations and distortion which may result in occurrence of failures.[Chinese Medical Equipment Journal,2024,45(3):29-35]

To understand the pathogenicity,virulence genes,drug resistance genes,and drug resistance of Staphylococcus aureus isolated from yaks in some areas of Lhasa and Nagqu City,55 yak nasal swab samples were analyzed for S.aureus in this study.The cocci were isolated and identified,and the carriage of virulence genes and drug resistance genes,as well as the pathogenicity and drug sensitivity of the isolated S.aureus strains,were detected with PCR,artificially infected mice,and the K-B drug susceptibility disk method.Seven strains of S.aureus were isolated from the 55 yak nasal swab samples,with an iso-lation rate of 12.73％.The isolated strains were all pathogenic to mice,with a fatality rate exceeding 60％.These seven strains of S.aureus carried three drug resistance genes(tetM,tet,and mecA)and six virulence genes(seb,sec,clfA,hla,hlb,and nuc).The detection rate of the three drug resistance genes was 100％,whereas the detection rate of the six virulence genes in the isolates ranged from 83.33％to 100％.The resistance rates of the isolated strains to penicillin,ampicillin,and cotrimox-azole reached 85.71％-100％,whereas the resistance rates to tetracycline and ceftazidime were both 28.57％.Thus,yaks in Lhasa and Nagqu cities were found to be infected by S.aureus strains carrying various drug-resistance genes and virulence genes.These strains were highly pathogenic and showed sensi-tivity to most antibacterial drugs.These findings may serve as a reference for treating S.aureus infection in yaks in the cities of Lhasa and Nagqu.

Objective:To optimize the technical parameters related to the preparation of novel frozen human platelets and formulate corresponding protocol for its preparation.Methods:Novel frozen human platelets were prepared with O-type bagged platelet-rich plasma(PRP),the key technical parameters(DMSO addition,incubation time,centrifugation conditions,etc.)of the preparation process were optimized,and the quality of the frozen platelets was evaluated by routine blood tests,apoptosis rate,platelet activation rate and surface protein expression level.Results:In the preparation protocol of novel frozen human platelets,the operation of centrifugation to remove supernatant was adjusted to before the procedure of platelets freezing,and the effect of centrifugation on platelets was minimal when the centrifugation condition was 800 xg for 8 min.In addition,platelets incubated with DMSO for 30 min before centrifugation exhibited better quality after freezing and thawing.The indexes of novel frozen human platelets prepared with this protocol remained stable after long-term cryopreservation.Conclusion:The preparation technique of novel frozen human platelets was established and the protocol was formulated.It was also confirmed that the quality of frozen platelets could be improved by incubating platelets with DMSO for 30 min and then centrifuging them at 800 ×g for 8 min in the preparation of novel frozen human platelets.

Aim To examine the neuroprotective im-pacts of total saponins from Trillium tschonoskii maxim(TST)on cerebral ischemia-reperfusion injury(CIRI)in rats and delve into the mechanisms of ferroptosis.Methods The CIRI model was prepared by dividing male SD rats into the model group,TST(0.1 g·kg-1)group,Donepezil hydrochloride(0.45 mg·kg-1)group,and sham group.The cognitive functions of rats in each group were assessed through the Morris water maze test,the changes in neurological function were evaluated using the Zea-Longa method,the infarct area was observed via TTC staining,and the pathologi-cal alterations in brain tissue were analysed using HE and Nissl staining.To further investigate the underly-ing mechanism,the mitochondrial structural changes were examined using transmission electron microscopy,and the levels of GSH-PX,MDA,and SOD were ana-lyzed.Additionally,the expressions of GPX4 and Nrf2 proteins were evaluated through immunohistochemistry and immunofluorescence.Furthermore,the protein lev-els of Keap1/Nrf2/HO-1 and Nrf2/SLC7A11/GPX4 pathways in rats were examined using Western blot-ting.Results The rats in the model group displayed diminished learning and memory capabilities in com-parison to those in the sham group,as well as a signifi-cantly increased cerebral infarction area and higher neurological function scores(P＜0.01),significantly increased cerebral infarct area,disordered and loosely arranged neurons,and reduced Nissl bodies.Addition-ally,mitochondria showed typical signs of ferroptosis.Changes related to ferroptosis included decreased activ-ities of SOD and GSH-PX(P＜0.01)and increased MDA levels(P＜0.01).The expression of GPX4 and Nrf2-positive cells was significantly reduced,along with decreased fluorescence intensity of GPX4.Further-more,the protein expression of Keap1,Nrf2,HO-1,GPX4,SLC7A11 in the hippocampus decreased(P＜0.05,P＜0.01).Following the administration of TST,these effects showed improvement.Conclusions TST has neuroprotective effects,enhancing learning and memory abilities while reducing oxidative stress levels.The mechanism may involve the inhibition of ferroptosis through the Keap-1/Nrf2/HO-1 and Nrf2/SLC7 A11/GPX4 pathways.

Acute lung injury (ALI), as a common clinical emergency, is pulmonary edema and diffuse lung infiltration caused by inflammation. The lack of non-invasive alert strategy, resulting in failure to carry out preventive treatment, means high mortality and poor prognosis. Stimulator of interferon genes (STING) is a key molecular biomarker of innate immunity in response to inflammation, but there is still a lack of STING-targeted strategy. In this study, a novel STING-targeted PET tracer, [¹⁸F]FBTA, was labeled with high radiochemical yield (79.7 ± 4.3%) and molar activity (32.5 ± 2.9 GBq/μmol). We confirmed that [¹⁸F]FBTA has a strong STING binding affinity (K_d = 26.86 ± 6.79 nmol/L) and can be used for PET imaging in ALI mice to alert early lung inflammation and to assess the efficacy of drug therapy. Our STING-targeted strategy also reveals that [¹⁸F]FBTA can trace ALI before reaching the computed tomography (CT) diagnostic criteria, and demonstrates its better specificity and distribution than [¹⁸F]fluorodeoxyglucose ([¹⁸F]FDG).

Objective To investigate the distribution and drug resistance of pathogenic bacteria for infection after liver transplantation, and to provide a scientific basis for the rational clinical application of antibiotics. Methods The pathogenic bacteria isolated from the specimens of 904 patients with infection after liver transplantation in The Affiliated Hospital of Qingdao University from March 2014 to December 2021 were analyzed in terms of distribution and drug resistance. WHONET 5.6 software was used to perform a statistical analysis of strains and bacterial resistance rate, and Excel was used to analyze the sources of specimens, composition ratios, and distribution of pathogenic bacteria. Results A total of 2 208 non-repetitive pathogenic bacteria were isolated, mainly from the specimens of respiratory tract (31.25%), bile (22.28%), ascites (13.18%), blood (8.38%), and drainage fluid (4.62%). The top 10 pathogenic bacteria were Klebsiella pneumoniae subspecies (10.69%), Enterococcus faecium (10.42%), Escherichia coli (8.24%), Pseudomonas aeruginosa (8.24%), Staphylococcus epidermidis (8.06%), Acinetobacter baumannii (7.93%), Stenotrophomonas maltophilia (6.61%), Enterobacter cloacae (3.22%), Staphylococcus haemolyticus (3.08%), and Staphylococcus aureus (2.94%), accounting for 69.43% of the total pathogenic bacteria. Pseudomonas aeruginosa, Stenotrophomonas maltophilia, Klebsiella pneumoniae subspecies, and Acinetobacter baumannii were the main pathogenic bacteria isolated from respiratory tract specimens; Enterococcus faecium was the main pathogenic bacterium isolated from bile, ascites, and drainage fluid specimens; Escherichia coli , Staphylococcus epidermidis , and Klebsiella pneumoniae subspecies were the main pathogenic bacteria isolated from blood specimens. Drug sensitivity data showed that Enterobacterales bacteria had a relatively high resistance rate to cephalosporins and fluoroquinolones and a resistance rate of < 10% to amikacin among aminoglycosides, with no strains resistant to tigecycline; compared with Escherichia coli , Klebsiella pneumoniae subspecies had a higher resistance rate to meropenem (14.71% vs 5.66%) and imipenem (11.35% vs 6.29%); non-fermentative bacteria had a relatively high resistance rate to carbapenems, with a resistance rate of < 10% to tigecycline and colistin. Among Gram-positive cocci, Enterococcus faecium had a resistance rate of 6.17% to vancomycin and 2.44% to quinupristin/dalfopristin, with no strains resistant to tigecycline and linezolid; Staphylococcus epidermidis had a resistance rate of > 50% to macrolides, fluoroquinolones, sulfonamides, and lincomycin, and a small part of these strains were resistant to linezolid and quinupristin/dalfopristin (< 3%), with no Staphylococcus epidermidis strains resistant to tigecycline and vancomycin. A total of 287 drug-resistant strains were monitored, accounting for 13%, among which there were 128 carbapenem-resistant Acinetobacter baumannii strains, 88 carbapenem-resistant Pseudomonas aeruginosa strains, 26 carbapenem-resistant Klebsiella pneumoniae subspecies strains, 11 carbapenem-resistant Escherichia coli strains, 23 methicillin-resistant Staphylococcus aureus strains, and 11 vancomycin-resistant Enterococcus strains. The carbapenem-resistant Klebsiella pneumoniae subspecies strains mainly produced serine carbapenemase, and the carbapenem-resistant Escherichia coli strains mainly produced metal β-lactamase. Conclusion Gram-negative bacteria are the main pathogenic bacteria for infection after liver transplantation, and there are differences in the distribution of pathogenic bacteria between different types of specimens. The resistance rate of some strains tend to increase, and therefore, it is necessary to strengthen the management of nosocomial infection and antibiotics.

Tissue regeneration is an important engineering method for the treatment of oral soft and hard tissue defects.Growth factors,as one of the three elements of tissue regeneration,are a necessary condition for tissue regeneration.Concentrated growth factor(CGF)is a new generation of blood extract prepared by changing the centrifugal speed on the basis of the preparation of platelet-rich plasma(PRP)and platelet-rich fibrin(PRF).It contains abundant growth factors and a fibrin matrix with a three-dimensional network structure,being capable of activating angiogenesis and promoting tissue regeneration and healing.CGF has been widely used in the repair and regeneration of oral soft and hard tissues.This paper introduces the preparation and composition of CGF and reviews the application of CGF in oral implantation and the regeneration of oral bone tissue,periodontal tissue,and dental pulp tissue.
Platelet-Rich Plasma/metabolism* ; Platelet-Rich Fibrin ; Cell Proliferation ; Bone and Bones ; Intercellular Signaling Peptides and Proteins/metabolism* ; Bone Regeneration

Objective: To investigate the predictive value of glycosylated hemoglobin A1c/apolipoprotein A-1 (HbA1c/ApoA-1) ratio for major adverse cardiovascular events (MACEs) in patients with acute coronary syndrome (ACS). Methods: The present study is a retrospective cohort study. ACS patients who were hospitalized and underwent coronary angiography at Beijing Hospital from March 2017 to March 2019 were enrolled. Baseline information such as sex, age, previous history, Gensini score, HbA1c and ApoA-1 were analyzed. Patients were divided into two groups according to presence or absence of MACEs and the difference on HbA1c/ApoA-1 ratio was compared between the two groups. According to the tertiles of HbA1c/ApoA-1 levels, patients were divided into high (5.87-16.12), medium (4.50-5.83) and low (2.11-4.48) HbA1c/ApoA-1 groups. Cox proportional risk model was used to evaluate the differences in MACEs and all-cause mortality among the three groups. Kaplan-Meier survival analysis was used to compare the differences of MACEs between the various HbA1c/ApoA-1 groups. Results: A total of 366 ACS patients were included in this study. The mean age of the patients was (65.9±10.3) years. There were 59 MACEs and 10 all-cause deaths during the mean of (22.3±4.4) months follow-up. After adjusting for age, systolic blood pressure, history of diabetes and Gensini score, the incidence of MACEs was 2.45 times higher in the high HbA1c/ApoA-1 group than in the low HbA1c/ApoA-1 group (95%CI 1.16-5.18, P=0.019). There was no significant difference in all-cause mortality between the high and low HbA1c/ApoA-1 groups (P=1.000). Kaplan-Meier survival analysis showed that patients in the high HbA1c/ApoA-1 group had the highest risk of MACEs, while patients in the low HbA1c/ApoA-1 group had the lowest risk of MACEs (P<0.01). Spearman rank correlation analysis showed that HbA1/ApoA-1 ratio was positively correlated with Gensini score in ACS patients (r=0.274, P<0.01). Conclusion: High HbA1c/ApoA-1 ratio was an independent risk factor for MACEs in ACS patients. Patients with high HbA1c/ApoA-1 ratio had more severe coronary artery disease lesions. HbA1c/ApoA-1 ratio may be used as a potential risk stratification biomarker for ACS patients, it might be useful for the early identification of high-risk population and for predicting the incidence of MACEs among ACS patients.
Aged ; Humans ; Middle Aged ; Acute Coronary Syndrome/diagnosis* ; Apolipoprotein A-I/analysis* ; Biomarkers/analysis* ; Glycated Hemoglobin/analysis* ; Percutaneous Coronary Intervention ; Retrospective Studies ; Risk Factors ; Predictive Value of Tests

In 2006, 2014 and 2020, the positive rates of HBsAg in 560, 384 and 402 children aged 1 to 14 years were 4.5%, 2.6% and 2.5%, respectively, with no statistically significant differences (P>0.05). The positive rate of anti-HBs was highest in 2014 (57.8%) and lowest in 2006 (34.1%) (P<0.05). The positive rate of anti-HBc was highest in 2006 (15.7%), and decreased in 2014 (7.8%) and 2020 (5.7%) (P<0.001). The timely rate of the first dose of hepatitis B vaccine for children in Lhasa in 2006, 2014 and 2020 was 7.7% (43/560), 50.3% (193/384) and 94.8% (381/402), respectively. The overall vaccination rates were 15.4% (86/560), 35.2% (135/384) and 96.0% (386/402), respectively, showing a trend of gradual increases (χtrend values were 718.63 and 589.59, both P values<0.001).
Child ; Humans ; Hepatitis B Vaccines ; Hepatitis B/prevention & control* ; Hepatitis B Surface Antigens ; Hepatitis B virus ; Hepatitis B Antibodies ; Vaccination