ObjectiveTo understand the seropositivity of neutralizing antibodies (NAb) and low-level NAb against SARS-CoV-2 infection in the community residents, and to explore the impact of COVID-19 vaccination and SARS-CoV-2 infection on the levels of NAb in human serum. MethodsOn the ground of surveillance cohort for acute infectious diseases in community populations in Shanghai, a proportional stratified sampling method was used to enroll the subjects at a 20% proportion for each age group (0‒14, 15‒24, 25‒59, and ≥60 years old). Blood samples collection and serum SARS-CoV-2 NAb concentration testing were conducted from March to April 2023. Low-level NAb were defined as below the 25^th percentile of NAb. ResultsA total of 2 230 participants were included, the positive rate of NAb was 97.58%, and the proportion of low-level NAb was 25.02% (558/2 230). Multivariate logistic regression analysis indicated that age, infection history and vaccination status were correlated with low-level NAb (all P<0.05). Individuals aged 60 years and above had the highest risk of low-level NAb. There was a statistically significant interaction between booster vaccination and one single infection (aOR=0.38, 95%CI: 0.19‒0.77). Compared to individuals without vaccination, among individuals infected with SARS-CoV-2 once, both primary immunization (aOR=0.23, 95%CI: 0.16‒0.35) and booster immunization (aOR=0.12, 95%CI: 0.08‒0.17) significantly reduced the risk of low-level NAb; among individuals without infections, only booster immunization (aOR=0.28, 95%CI: 0.14‒0.52) showed a negative correlation with the risk of low-level NAb. ConclusionsThe population aged 60 and above had the highest risk of low-level NAb. Regardless of infection history, a booster immunization could reduce the risk of low-level NAb. It is recommended that eligible individuals , especially the elderly, should get vaccinated in a timely manner to exert the protective role of NAb.

Aim To investigate the role of metabolites of eicosapentaenoic acid (EPA) in promoting the transdifferentiation of pancreatic α cells to β cells. Methods Male C57BL/6J mice were injected intraperitoneally with 60 mg/kg streptozocin (STZ) for five consecutive days to establish a type 1 diabetes (T1DM) mouse model. After two weeks, they were randomly divided into model groups and 97% EPA diet intervention group, 75% fish oil (50% EPA +25% DHA) diet intervention group, and random blood glucose was detected every week; after the model expired, the regeneration of pancreatic β cells in mouse pancreas was observed by immunofluorescence staining. The islets of mice (obtained by crossing GCG

Twelve compounds were isolated from the ethyl acetate fraction of the 80% aqueous ethanol extract of the roots and stems of Dalbergia rimosa Roxb. by silica gel, MCI, Sephadex LH-20 column chromatography, and semi-preparative HPLC. Their structures were identified by spectral analysis such as UV, IR, MS, 1D/2D NMR and by comparison with literature information as dalbergiquinol A (1), dalbergiquinol B (2), R-(-)-3′-hydroxy-2,4,5-trimethoxydalbergiquinol (3), neokhriol A (4), mucronulatol (5), (3R)-7,2′,3′-trihydroxy-4′-methoxy-isoflavane (6), isomucronulatol (7), (3S)-violanone (8), 3′-O-methylviolanone (9), eryvarin M (10), (±)-α,3,4,2′,4′-pentahydroxydihydrochalcone (11) and (-)-butin (12). Compound 1 and 2 are new compounds, and compounds 3-12 were isolated from this plant for the first time. Compounds 1, 2, 4, 6, 8, 11, 12 showed good scavenging effect on DPPH free radical.

Objective To design an assisted patient conveying and vibration damping system to solve the problems of operator fatigue and patient bump during casualty evacuation.Methods The assisted patient conveying and vibration damping system was composed of several conveying straps and a vibration damping mechanism.The conveying straps were made up of a waist strap,two shoulder straps,a chest strap,adhesive straps and joint components,and the joint components included adjusting buckles,big buckles,small buckles,connecting buckles and hook mechanisms;the vibration damping mechanism adopted the technical form of extension handle combined with vibration absorber,in which the extension handle was made of rigid material and the vibration absorber was equipped with a scissor guiding mechanism.Tests were carried out on the system to record the operating time of the operators and to analyze the system's vibration damping characteristics.Results The system developed extended the operating time of the stretcher conveyers while reduced the vibration during casualty transport,with a maximum vibration reduction of 71.73％.Conclusion The system developed gains advantages in low vibration and low workload,and can be used for casualty conveying in poor road conditions.[Chinese Medical Equipment Journal,2024,45(1):15-24]

AIM To study the chemical constituents from the leaves of Cyanocarya paliurus(Batalin)Iljinskaja and their α-glucosidase inhibitory activities.METHODS The 95%ethanol extract from the leaves of C.paliurus was isolated and purified by macroporous resin,silica gel,Sephadex LH-20,polyamide,C18 reversed-phase silica gel and semi-preparative HPLC,then the structures of obtained compounds were identified by physicochemical properties and spectral data.Their α-glucosidase inhibitory activities were evaluated by PNPG.RESULTS Fifteen compounds were isolated and identified as cyclopaloside C(1),cyclopaloside A(2),juglanosides E(3),vaccinin A(4),ent-murin A(5),kaempferol 3-O-α-L-rhamnopyranoside(6),kaempferol-3-O-β-D-glucopyranoside(7),kaempferol-3-O-β-D-glucuronide methyl ester(8),kaempferol-3-O-β-D-glucuronide ethyl ester(9),kaempferol-3-O-β-D-glucuronide butyl ester(10),quercetin-3-O-α-L-rhamnopyranoside(11)quercetin-3-O-β-D-glucopyranoside(12),quercetin-3-O-β-D-galactopyranoside(13),quercetin-3-O-β-D-glucuronide butyl ester(14),dihydrokaempferol(15).The IC50 value of total extracts ihibited α-glucosidase was(1.83±0.04)μg/mL,and the IC50 values of compounds 1,4-5 were(29.48±1.86),(0.50±0.07),(0.71±0.07)μmol/L,respectively.CONCLUSION Compound 1 is a new tetrahydronaphthalene glycoside.Compounds 4-5,8-10 and 14 are isolated from the leaves of C.paliurus for the first time.Compounds 4-5 are relatively rare flavonoid lignans with potential inhibitory activities against α-glucosidase.

Objective To investigate the effect of oral fish oil on wound healing and related indexes in patients with diabetic foot ulcer(DFU).Methods A randomized,double-blind,placebo-controlled design was used to recruit 68 patients with DFU aged 18-80 years old in the hospital,and the baseline clinical data of the patients were collected.The patients were randomly divided into experimental group(32 cases,fish oil soft capsule,3 g/d)and control group(33 cases,corn oil soft capsule,3 g/d)by random number generated by Ex-cel,and the intervention lasted for 12 weeks.The primary endpoints included the proportion of complete wound healing and healing area≥50%.The secondary endpoints included wound area,healing time,inflamma-tion index,glucose metabolism index,nutrition related index and wound reinfection.Additionally,the influen-cing factors of wound healing were analyzed.Results After intervention,the proportion of complete wound healing and healing area≥50%in the experimental group was significantly higher than that in the control group(P=0.007,0.039).In the subjects with complete wound healing,the mean healing time in the experi-mental group was shorter than that in the control group,but the difference was not statistically significant(P=0.132).The reduction area of wound area in the experimental group was significantly larger than that in the control group(P=0.045).The decrease of interleukin(IL)-6 and IL-8 in the experimental group was significantly higher than that in the control group(P<0.05).There was no significant difference in the reduc-tion of C-reactive protein(CRP),tumor necrosis factor-α(TNF-α),neutrophil-to-lymphocyte ratio(NLR),glycated hemoglobin A1c(HbA1c)and platelet-to-lymphocyte ratio(PLR)between the two groups(P>0.05).The improvement of prealbumin(PA)in the experimental group was higher than that in the control group,but the difference was not statistically significant(P>0.05).Multivariate logistic regression analysis showed that oral fish oil intervention(OR=6.771,95%CI:1.787-25.652),HbA1c(OR=4.149,95%CI:1.026-16.770)and ulcer type(OR=4.319,95%CI:1.026-18.173)were the influencing factors of wound healing(P<0.05).Conclusion Oral fish oil promotes wound healing in patients with DFU,which may be re-lated to improving the level of chronic inflammation in the body.

The abuse of novel phenylcyclohexylpyridine drugs poses a significant threat to societal safety. The novel psychoactive substance 2-methyl-deschloroketamine (2-MDCK), belonging to the phenylcyclohexylpyridine class, has recently surfaced as a new compound. However, there is a lack of understanding regarding its metabolic pathways and the identification of suitable biomarkers. In this study, a human liver microsomal model was established, and ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) technology was applied to investigate the in vitro metabolism and products of 2-MDCK. The results indicate that 2-MDCK undergoes various metabolic reactions, including dehydrogenation, deamination, hydroxylation, and demethylation, leading to the formation of eight metabolites. By conducting actual testing on hair samples from 2-MDCK abusers, the existence of six metabolites was confirmed. Comparing the metabolic products in the liver microsomal in vitro model, M3.1 and M4.1 were identified as biomarkers for 2-MDCK consumption. Five samples of abusers of 2-methyl-dechloroketamine were provided by the Anti-Drug Brigade of the Hangzhou Public Security Bureau. Negative hair samples were provided by laboratory volunteers, and all samples were obtained with the informed consent of the volunteers. These findings provide a scientific basis for the detection and identification of 2-MDCK and its metabolites, as well as crucial support for the study of the metabolic mechanisms of similar novel psychoactive substances in the phenylcyclohexylpyridine class. This research holds significant importance in addressing the issue of abuse of new psychoactive substances.

Objective To evaluate the malaria diagnostic capability in Shanghai Municipal Malaria Diagnostic Reference Laboratory from 2017 to 2022 and to analyze factors affecting the diagnosis results, so as to provide the scientific evidence for increasing the laboratory malaria diagnostic capability during the post-elimination stage. Methods Plasmodium-negative blood smears were randomly sampled using a proportional sampling method each quarter during the period from 2017 to 2022 and scored by Shanghai Municipal Malaria Diagnostic Reference Laboratory. Malaria cases’ blood samples from district centers for disease control and prevention in Shanghai Municipality were re-reviewed using microscopy and multiplex PCR assay to evaluate the capability of malaria diagnosis. Results A total of 7 746 quality control blood smears were collected from district centers for disease control and prevention in Shanghai Municipality from 2017 to 2022, with a mean score of (76.74 ± 14.34) points and a qualification rate of 86.65% (6 712/7 746). A total of 387 blood smears were re-reviewed from 2017 to 2022, with an overall coincidence of 96.38% (373/387) for malaria diagnosis and 95.06% (308/324) for parasite species identification, and there were no significant differences in the coincidence for either malaria diagnosis (χ² = 2.57, P > 0.05) or parasite species identification among years (χ² = 1.04, P > 0.05). A total of 384 whole blood samples were collected from district centers for disease control and prevention, and the detection of whole blood samples was 70.31% (270/384) in district centers for disease control and prevention. All 384 whole blood samples were re-reviewed by Shanghai Municipal Malaria Diagnostic Reference Laboratory using a multiplex PCR assay from 2017 to 2022, with an overall coincidence of 94.07% (254/270) for malaria diagnosis and 99.55% (223/224) for parasite species identification, and there were no significant differences in the coincidence for either malaria diagnosis (χ² = 5.77, P > 0.05) or parasite species identification among years (χ² = 8.37, P > 0.05). The overall coincidence rates of Plasmodium-positive and negative whole blood samples were 100.00% (224/224) and 65.22% (30/46) in district centers for disease control and prevention, with a significant difference (χ² = 82.82, P < 0.001), and there was a significant difference in the coincidence rate for identification of P. falciparum, P. vivax, P. malariae and P. ovale (χ² = 24.28, P < 0.001). A total of 1 584 blind blood smears subjected to microscopic examinations by centers for disease control and prevention and medical institutions across all districts in Shanghai Municipality from 2017 to 2022, with a 96.15% (1 523/1 584) correct rate for malaria diagnosis and 85.07% (1 003/1 179) for parasite species identification, and there were significant differences in the correct rate of both malaria diagnosis (χ² = 20.98, P < 0.001) and parasite species identification among years (χ² = 70.77, P < 0.001). A total of 320 blind nucleic acid samples from malaria cases were tested, with a 99.38% (318/320) correct rate for malaria diagnosis and 100.00% (225/225) for parasite species identification, and there was no significant difference in the correct rate of malaria diagnosis among years (χ² = 6.04, P > 0.05). Conclusions There were still shortcomings in blood smears preparation, microscopic examinations and nucleic acid testing in centers for disease control and prevention across all districts in Shanghai Municipality from 2017 to 2022. A greater role in the quality control of malaria diagnosis is recommended for Shanghai Municipal Malaria Diagnostic Reference Laboratory to prevent the re-establishment of imported malaria and consolidate the elimination achievements.

Objective:To explore the effectiveness of a hysteroscopic endometrial lesion diagnosis model de-veloped based on deep learning(DL)algorithm combined with gradient-weighted class activation mapping(Grad-CAM)visualization technology.Methods:303 hysteroscopy videos(4781 images)of 291 patients who un-derwent hysteroscopy examination in the Department of Gynecology,Renmin Hospital of Wuhan University from June 1,2021 to December 31,2022 were selected.The dataset was divided into a training set(3703 images)and a test set(1078 images)by weight sampling method.After the training set was used for model learning and train-ing,two model architectures,residual neural network(ResNet18)and efficient neural network(EfficientNet-B0),were selected to verify the model in the test set by five-class and two-class classification tasks,respectively.Tak-ing histopathology as the gold standard,the diagnostic efficacy was evaluated to select the optimal model,and the Grad-CAM layer was embedded in the optimal model to output hysteroscopy images of Grad-CAM.Results:①In the five-class classification tasks,the accuracy of EfficientNet-B0 model(93.23％)was higher than that of Res-Net18 model(84.23％);the area under the curve(AUC)of EfficientNet-B0 model in the diagnosis of five disea-ses,including atypical endometrial hyperplasia,endometrial polyps,endometrial cancer,endometrial atypical hy-perplasia,and submucous myoma,was slightly higher than that of ResNet18 model,and the AUC of both models was almost above 0.980.②In the binary classification task of accuracy and the evaluation of specificity,the two models were similar,both above 93.00％,and the sensitivity of EfficientNet-B0 model(91.14％)was significantly better than that of ResNet18 model(77.22％).③EfficientNet-B0 model combined with Grad-CAM algorithm could identify the abnormal areas in the image.After biopsy and pathological examination,it was confirmed that about 95％of the marked areas in the model's output heatmap were lesion areas.Conclusions:The hysteroscopy di-agnostic model developed by EfficientNet-B0 model combined with Grad-CAM has high diagnostic accuracy,sen-sitivity,and specificity,and has application value in the diagnosis of endometrial lesions.

Objective:To explore the effectiveness of a hysteroscopic endometrial lesion diagnosis model de-veloped based on deep learning(DL)algorithm combined with gradient-weighted class activation mapping(Grad-CAM)visualization technology.Methods:303 hysteroscopy videos(4781 images)of 291 patients who un-derwent hysteroscopy examination in the Department of Gynecology,Renmin Hospital of Wuhan University from June 1,2021 to December 31,2022 were selected.The dataset was divided into a training set(3703 images)and a test set(1078 images)by weight sampling method.After the training set was used for model learning and train-ing,two model architectures,residual neural network(ResNet18)and efficient neural network(EfficientNet-B0),were selected to verify the model in the test set by five-class and two-class classification tasks,respectively.Tak-ing histopathology as the gold standard,the diagnostic efficacy was evaluated to select the optimal model,and the Grad-CAM layer was embedded in the optimal model to output hysteroscopy images of Grad-CAM.Results:①In the five-class classification tasks,the accuracy of EfficientNet-B0 model(93.23％)was higher than that of Res-Net18 model(84.23％);the area under the curve(AUC)of EfficientNet-B0 model in the diagnosis of five disea-ses,including atypical endometrial hyperplasia,endometrial polyps,endometrial cancer,endometrial atypical hy-perplasia,and submucous myoma,was slightly higher than that of ResNet18 model,and the AUC of both models was almost above 0.980.②In the binary classification task of accuracy and the evaluation of specificity,the two models were similar,both above 93.00％,and the sensitivity of EfficientNet-B0 model(91.14％)was significantly better than that of ResNet18 model(77.22％).③EfficientNet-B0 model combined with Grad-CAM algorithm could identify the abnormal areas in the image.After biopsy and pathological examination,it was confirmed that about 95％of the marked areas in the model's output heatmap were lesion areas.Conclusions:The hysteroscopy di-agnostic model developed by EfficientNet-B0 model combined with Grad-CAM has high diagnostic accuracy,sen-sitivity,and specificity,and has application value in the diagnosis of endometrial lesions.