A new method was developed for simultaneous and efficient determination of linear perfluorooctanoic acid(n-PFOA)and linear perfluorooctane sulfonate(n-PFOS),and their typical branched isomers in seawater by online solid phase extraction-liquid chromatography-tandem mass spectrometry(Online SPE-LC-MS/MS).Only centrifugation of the seawater sample was required to remove the particulate matter,and then the seawater sample was directly injected and analyzed by online SPE-LC-MS/MS.An Eclipse Plus-C18 guard column was selected as SPE column for online enrichment of linear and branched isomers,and a F5 PFP column(150 mm×2.1 mm,2.7 μm)was used as the analytical column.Under the optimized experimental conditions,the separation and detection of all PFOA and PFOS linear and branched isomers could be completed within 20 min.The spiked recoveries of various target compounds ranged from 82.9%to 107.7%with detection limits and limits of quantification of 0.10-1.05 ng/L and 0.30-2.11 ng/L,respectively.The method was characterized by good precision(RSD≤9.10%)and linearity(R2≥0.990).Subsequently,linear and branched isomers of PFOA and PFOS in surface and bottom seawater samples collected from the Laizhou Bay of China were determined.The results showed that the detection rate of all the four branched PFOA isomers were 100%,with the highest average concentration of 25.85 ng/L found for 6m-PFOA,which accounted for 11.79%of the∑PFOA.For the five branched isomers of PFOS,the highest detection rate of 90.84%was found for 5m-PFOS.The highest average concentration of 0.64 ng/L was observed for 3m-PFOS,accounting for 19.88%of ∑PFOS.The proposed method provided an effective detection tool for qualitative and quantitative detection of PFOA and PFOS isomers in the marine aquatic environment.

An efficient analytical method was developed for simultaneous detection of alkylamines and alkylamides in food packaging plastics using liquid chromatography-high resolution mass spectrometry(LC-HRMS).Based on the physicochemical properties of alkylamines and alkylamides,as well as the complexity of plastic samples,sample pretreatment and chromatographic-mass spectrometric parameters were optimized.The samples were extracted by vortex-ultrasonic extraction with a methanol-acetonitrile mixture for 15 min,followed by nitrogen evaporation to concentrate the extract,reconstitution,and analysis.The chromatographic mobile phase consisted of 0.1%formic acid aqueous solution and acetonitrile,and a gradient elution was used.The electrospray ionization(ESI)source was operated in positive ion mode,and mass spectrometry data were collected in full scan and data-dependent acquisition modes.Quantification was performed using an isotope-labeled internal standard method.The results showed that within the quantification range of 1-1000 ng/mL,the calibration curves exhibited good linearity(R2>0.99).Some compounds interfered with the validation experiments at higher concentrations,so only 10 kinds of target analytes were validated.Using a mixed food packaging plastic matrix,the recoveries at spiking levels of 40,400,and 4000 ng/g were mostly between 66.0%and 117.1%,with relative standard deviations ranging from 0.6%to 10.6%.The method was applied to detect 14 food packaging plastic samples,and the results showed that the concentrations of alkylamines and alkylamides ranged from not detected to 8924 ng/g.This method offered high sensitivity and accuracy,and was suitable for the screening and quantitative determination of alkylamines and alkylamides in plastics.

The aim of this investigation was to determine the optimal storage medium for testicular hypothermic transportation and identify the ideal concentration for the application of the protective agent 5-aminolevulinic acid (5-ALA). Furthermore, this study aimed to explore the underlying mechanism of the protective effects of 5-ALA. First, we collected and stored mouse testicular fragments in different media, including Hank's balanced salt solution (HBSS; n = 5), Dulbecco's Modified Eagle Medium/Nutrient Mixture F-12 (DMEM/F12; n = 5), and alpha-minimum essential medium (αMEM; n = 5). Storage of testicular tissue in HBSS preserved the integrity of testicular morphology better than that in the DMEM/F12 group ( P < 0.05) and the αMEM group ( P < 0.01). Testicular fragments were subsequently placed in HBSS with various concentrations of 5-ALA (0 [control], 1 mmol l -1 , 2 mmol l -1 , and 5 mmol l -1 ) to determine the most effective concentration of 5-ALA. The 2 mmol l -1 5-ALA group ( n = 3) presented the highest positive rate of spermatogonial stem cells compared with those in the control, 1 mmol l -1 , and 5 mmol l -1 5-ALA groups. Finally, the tissue fragments were preserved in HBSS with control ( n = 3) and 2 mmol l -1 5-ALA ( n = 3) under low-temperature conditions. A comparative analysis was performed against fresh testes ( n = 3) to elucidate the underlying mechanism of 5-ALA. Gene set enrichment analysis (GSEA) for WikiPathways revealed that the p38 mitogen-activated protein kinase (MAPK) signaling pathway was downregulated in the 2 mmol l -1 5-ALA group compared with that in the control group (normalized enrichment score [NES] = -1.57, false discovery rate [FDR] = 0.229, and P = 0.019). In conclusion, these data suggest that using 2 mmol l -1 5-ALA in HBSS effectively protected the viability of spermatogonial stem cells upon hypothermic transportation.
Male ; Animals ; Testis/cytology* ; Aminolevulinic Acid/pharmacology* ; Mice ; Organ Preservation/methods* ; Organ Preservation Solutions/pharmacology* ; Cryopreservation/methods*

Objective To design a nuclear emergency medical rescue simulation platform to solve the problmes in nuclear accident scenario simulation,fidelity of on-site medical treatment training and training organization.Methords A nuclear emergency medical rescue simulation platform was developed with the technologies of virtual reality(VR),augmented reality(AR),spatial positioning,full-body motion capture,gesture simulation and three-dimensional modeling,Unity3D platform,3D Studio Max software and Visual Studio,which mainly consisted of a hardware system and a software system.The hardware system was composed of the AR training equipment and VR training equipment,of which,the AR training equipment included a surface contamination detector simulator,an individual decontaminator simulator and AR glasses,and the VR training equipment was made up of VR glasses,large-space localization equipment,backpack computers,data gloves and full-body motion capture equipment.The software system involved in several modules for theoretical knowledge teaching and assessment,VR/AR practical teaching training and VR/AR evaluation.Results The system realized simulated collaborative training and evaluation for medical emergency response to nuclear accidents.Conclusion The platform constructed contributes to solving the practical problems in organizing and implementing education and training for nuclear emergency medical rescue,and the education and training are both enhanced greatly.[Chinese Medical Equipment Journal,2024,45(9):50-56]

Aim To dynamically characterize neuronal damage in the cortex and hippocampus of mice follow-ing acute cerebral ischemia/reperfusion(I/R).Meth-ods Male C57BL/6J mice weighing 25-28 g under-went middle cerebral artery occlusion using the fila-ment method,followed by 1 hour of reperfusion to es-tablish the acute cerebral I/R injury mouse model.The experiment comprised a sham surgery group,I/R-6 h group,I/R-24 h group,and I/R-72 h group.Longa neurological function score was used to assess the neu-rological function.Triphenyltetrazolium chloride(TTC)staining was conducted to detect cerebral in-farct volume.Hematoxylin and eosin(HE)staining was utilized to observe brain tissue pathological dam-age.Nissl staining was performed to evaluate neuronal damage.Immunofluorescence histochemistry staining was employed to assess the activation of astrocytes and microglia,as well as neuronal loss.Transmission elec-tron microscopy was used to examine mitochondrial damage in hippocampal neurons.Western blot analysis was conducted to detect the expression levels of mito-chondrial fission-fusion-related proteins p-Drp1/Drp1,Mff,Fis1,and OPA1.Results With prolonged cere-bral I/R time,neurological functional impairment,cerebral infarct volume,neuronal damage in the cortex and hippocampus,glial cell activation,neuronal loss,and mitochondrial damage gradually worsened in mice.The expression of mitochondrial fission-related proteins increased gradually,while the expression of mitochon-drial fusion-related proteins decreased gradually.Con-clusions Neuronal pathological damage,such as glial cell activation,neuronal loss,and mitochondrial dam-age,is gradually aggravated with prolonged cerebral I/R time,which may be associated with mitochondrial dynamics imbalance.

Objective To compare the lipid-lowering efficacy and safety of fixed-dose combination and free combination of rosuvastatin and ezetimibe in hypercholesterolemia patients who fail to achieve low-density lipoprotein cholesterol(LDL-C)goal with statin monotherapy.Methods A total of 45 hypercholesterolemia patients who switched from statin monotherapy to fixed-dose combination of rosuvastatin and ezetimibe after failing to achieve target LDL-C goal admitted at cardiological departments of First Affiliated Hospital of Sun Yat-sen University,Nanhai Fourth People's Hospital,Foshan First People's Hospital,and Guangdong Provincial People's Hospital between March and June 2024 were enrolled and served as the study group.Another 120 hyper-cholesterolemia patients who treated with free combination of rosuvastatin and ezetimibe were se-lected from Xiamen Regional Health Medical Big Data Platform with propensity score matching and served as control group.The LDL-C level,LDL-C reduction,and changes in TC,HDL-C and TG levels in 4-6 weeks after the medication switch,as well as the safety indicators(AST,ALT,CK,Cre and eGFR)were compared between the two groups.Results In 4-6 weeks after the medication switch,the patients in the study group exhibited a significant decrease in LDL-C level(1.70±0.44 mmol/L vs 2.12±0.87 mmol/L,P＜0.01),obvious LDL-C reduction[(43.17±16.11)％vs(29.14±29.13)％,P＜0.01]when compared to those of the control group.The LDL-C goal attainment rate was significantly higher in the study group than the control group(71.11％vs 45.00％,P=0.003).In addition,there were no statistical differences in the levels of HDL-C and TG and the reductions of HDL-C and TG between the two groups in 4-6 weeks after treatment(P＞0.05).The study group obtained notably lower TC level and TC reduction than the control group in the time(P＜/0.05,P＜0.01).After treatment,no statistical differences were observed between the two groups in terms of AST,ALT,CK,Cre and eGFR(P＞0.05).Conclusion Com-pared to free combination of rosuvastatin and ezetimibe,fixed-dose combination can further reduce LDL-C level in hypercholesterolemia patients who have not achieved LDL-C goal with statin monotherapy,with higher LDL-C goal attainment rate and good safety.

Aim To research the neuroprotective effect of Haikun Shenxi (HKSX) medicated serum on N2a/ App695 cells and the underlying mechanism. Methods HKSX medicated serum was prepared and carbohydrate components in it was analyzed using high performance thin layer chromatography (HPTLC) . N2a/ App695 cells were intervened with HKSX medicated serum, the cytotoxicity of HKSX medicated serum was measured by MTT; AP[_

A new method for simultaneous determination of 23 kinds of per-and polyfluoroalkyl substances(PFASs)(13 kinds of perfluoro carboxylic acids,4 kinds of perfluoro sulfonic acids,and 6 kinds of new substitutes)in plant leaf tissue by ultra-high performance liquid chromatography-tandem mass spectrometry(UHPLC-MS/MS)using automatic online solid phase extraction(SPE)to remove the matrix interference components in plant crude extracts was developed.The plant leaf samples were extracted twice with 1%formic acid-methanol solution,then evaporated to dry,redissolved with 70%methanol solution,and directly injected for analysis.After 23 kinds of target PFASs were purified automatically by online SPE with a WAX column,the six-way valve was switched to rinse PFASs onto an alkaline mobile phase system-compatible C18 analytical column.Then,the 23 kinds of target PFASs were separated within 16 min by gradient elution using a binary mobile phase system of methanol/water(Containing 0.4%ammonium hydroxide).Tandem mass spectrometry was performed in multiple reaction monitoring(MRM)mode for online detection of various PFASs,and quantification was carried out by internal standard method.The results of the method validation showed that satisfactory average recoveries of 23 kinds of PFASs in plant leaf samples(64.2%-125.5%),precision(relative standard deviations(RSDs)of 0.7%-12.8%),linearity(R2＞0.990),and sensitivity(the detection limits(S/N=3)were in the range of 0.02-0.50 μg/kg)were achieved.Finally,this method was used to detect PFASs in the marine green tide algae(Enteromorpha prolifera)and several tree leaves,and a total of 6 kinds of PFASs were detected,in which PFBA was the main contaminant.Compared with the reported offline SPE methods,the proposed online SPE technique significantly simplified the sample pretreatment process and provided an automatic,simple,and environment-friendly method for the routine monitoring of legacy and emerging PFASs in plant tissues.

Objective To compare the effects of two arc(TA)and dual arc(DA)techniques on the dose distribution to the planning target volume(PTV)and organs at risk(OAR)in volumetric modulated arc therapy(VMAT)for lower mid-thoracic esophageal cancer.Methods Ten patients with lower mid-thoracic esophageal cancer who received radiation therapy at some hospital from July 2020 to June 2022 were selected retrospectively.A TA radiation therapy plan and a DA radiation therapy plan were developed for each patient using the Ray Arc module of RayStation 4.7.5.4 planning system,and the two kinds of radiation plans were compared in terms of dosimetric parameters including D2,D5,D50,D95,D98,homogeneity index(HI),conformity index(CI),beam-on time and total monitor unit for PTV and lung V5,V10,V20,V30 and Dmean and heartV30,V40 and Dmean and spine cord Dmax for OAR.SPSS 22.0 was used for statistical analysis.Results TA and DA radiation therapy plans had no significant differences in PTV CI,HI,D2,D5,D50,D95 and beam-on time(P＞0.05),and DA plan had D98 and total monitor unit higher obviously than those of TA plan(P＜0.05).In terms of OARs protection,DA plan had heart V30,V40 and Dmean slightly lower than those of TA plan with non-significantly differences(P＞0.05),while lung V5,V30 and Dmean and spine cordDmax significantly lower(P＜0.05).Conclusion DA technique gains advantages over TA technique in PTV dose distribution and dose to OAR,and the involvement of DA technique in preparing the VMAT plan for esophageal cancer contributes to enhancing the treatment efficacy.[Chinese Medical Equipment Journal,2024,45(1):62-66]

Objective: To compare the 5-year follow-up outcomes of radiofrequency catheter ablation (RFCA) combined with left atrial appendage closure (LAAC) and long-term oral anticoagulant (OAC) after RFCA in patients with atrial fibrillation. Methods: This retrospective cross-sectional study included patients with atrial fibrillation who underwent"one-stop"procedure in the First Affiliated Hospital of Ningbo University from September 2015 to December 2017 (RFCA+LAAC group). Baseline data of patients were collected. Propensity score matching at the ratio of 1∶1 was used to select patients with atrial fibrillation who took long-term OAC after RFCA (RFCA+OAC group). The maintenance rate of sinus rhythm and the incidence of adverse events during follow-up were compared between the two groups. Results: A total of 110 patients were enrolled in the RFCA+LAAC group and RFCA+OAC group, respectively. Age of patients was (67.4±8.8) years in RFCA+LAAC group, and there were 42 (38.2%) female patients. Age of patients was (67.3±7.9) years in RFCA+OAC group, and there were 47 (42.7%) female patients. The patients were followed up for mean of (5.3±1.1) years. There was no significant difference in the maintenance rate of sinus rhythm (log-rank: χ²=0.277, P=0.602) and incidence of ischemic stroke events (2.7% (3/110) vs. 4.5% (5/110), P=0.719) during follow-up between the two groups. The incidence of bleeding events (6.4% (7/110) vs. 18.2% (20/110), P=0.008) and major bleeding events (1.8% (2/110) vs. 8.2% (9/110), P=0.030) was significantly higher in the RFCA+OAC group than in the RFCA+LAAC group. Conclusion: There is no significant difference between RFCA+LAAC group and RFCA+OAC group in maintenance rate of sinus rhythm and incidence of ischemic stroke events. Patients in the RFCA+LAAC group have a lower risk of bleeding events compared to the RFCA+OAC group.
Humans ; Female ; Middle Aged ; Aged ; Male ; Atrial Fibrillation/surgery* ; Cross-Sectional Studies ; Follow-Up Studies ; Retrospective Studies ; Anticoagulants/therapeutic use* ; Catheter Ablation ; Ischemic Stroke