Objective:To compare the efficiency and purity of exosomes extracted from synovial fibroblasts of patients with rheumatoid arthritis by ultracentrifugation, size exclusion chromatography and modified polymer precipitation.Methods:The exosomes were extracted from human synovial fibroblasts by ultracentrifugation, size exclusion chromatography and modified polymer precipitation. Transmission electron microscopy, particle size detection and western Blot were used to identify the morphological characteristics, particle size distribution, concentration, and expression of marker proteins. One-way analysis of variance (ANOVA) was used for comparison among the three groups, and LSD- t test was used for pairwise comparison. P<0.05 was considered statistically significant. Results:Exosomes could be successfully obtained with all three extraction methods. The typical "saucer-like" structure could be observed under transmission electron microscope. The marker proteins of exosomes TSG101, Syntenin-1 and CD63 were all detectable by western blot. The peaks of main particle size were located within 30~150 nm. As for purity, the exosomes obtained by ultracentrifugation showed the highest purity, while modified polymer precipitation was the worst, with a large number of polymer particles and impurities protein. The purity of exosomes obtained by size exclusion chromatography was the moderate. For extraction efficiency, concentrations of exosomes particles obtained by the three methods were different ( F=9.61, P=0.049), and modified polymer precipitation was significantly higher than ultracentrifugation in terms of concentration of exosomes particles [(98.0±17.0)×10 10 particles/ml vs (11.6±7.7)×10 10 particles/ml, t=-4.34, P=0.023]. Conclusion:Human synovial fibroblasts derived exosomes canbe obtained by three methods. Ultracentrifugation is time-consuming, but can produce high-purity exosomes, which may be considered in the situation when high purity requirement with large volume samples are needed. Size exclusion chromatography is a good choice with high yield and purity exosomes, and suitable for small volume samples. Modified polymer precipitation is not recommended due to production of lowest purity exosomes.

Objective:To investigate the role of TcpC, a virulence factor of uropathogenic Escherichia coli (UPEC), in immune evasion, and analyze its related pathogenic mechanism. Methods:C57BL/6 mice were injected with 10 9 colony-forming unit of wild-type (CFT073 wt) or tcpc gene-knockout (CFT073 Δ tcpc) UPEC CFT073 strains from urethra into bladder to construct a mouse model of pyelonephritis. These mice were sacrificed 5 d after infection and their kidneys were taken to observe the gross pathological changes. Hematoxylin-eosin staining was used to observe histopathological changes in kidney tissues and immunohistochemistry was performed to locate TcpC in kidney tissues. The bacterial loads in urine samples of UPEC infected-mice were counted by ten-fold dilution method, and the presence of tcpc gene in the genomic DNA of bacteria from CFT073-infected mouse kidney or urine samples was measured by PCR. The expression of TcpC at mRNA level was detected by qRT-PCR after infecting dendritic cells with CFT073 wt strains. The influences of UPEC infection on the activation of NF-κB signaling pathway and the secretion of proinflammatory factors by dendritic cells were analyzed by Western blot and ELISA, respectively. The viability of UPEC strains in dendritic cells were observed by laser confocal microscope. Results:Compared with the CFT073 Δ tcpc group, the mice in the CFT073 wt group had obvious abscess in the kidneys as well as massive neutrophil infiltration and abundant TcpC in kidney tissues. The bacterial loads in the urine of CFT073 wt-infected mice were significantly higher than those in the urine of CFT073 Δ tcpc mice. PCR results showed that tcpc gene was successfully amplified from mouse kidney and urine samples. Increased expression of TcpC at both mRNA and protein levels was detected in CFT073 wt-infected dendritic cells. CFT073 wt infection inhibited the phosphorylation of NF-κB p50 and the production of proinflammatory factors in dendritic cells. TcpC promoted the survival of CFT073 wt in dendritic cells. Conclusions:TcpC expression increases significantly during CFT073 wt infection or in mice with CFT073 wt-induced pyelonephritis. It promotes the survival of CFT073 wt in dendritic cells by inhibiting the activation of NF-κB signaling pathway and reducing the secretion of pro-inflammatory cytokines. TcpC is involved in the pathogenesis of UPEC and immune evasion.

This article introduces a high-magnification electronic endoscope system that utilizes a continuous zoom optical design,enabling high-magnification imaging at the cellular level.By selecting an appropriate initial retrofocus structure,the optimized modulation transfer function(MTF)curve of the zoom objective lens approaches the diffraction limit.Additionally,the tip and operation parts of the system incorporate modular gas-tight sealing and multiple layers of protective structure.The design employs efficient sealing materials and precise packaging techniques to ensure the system's sealing performance.The experimental results indicate that,under conventional imaging,the resolution is equivalent to 39.37 μm in object space,and the field of view angle is larger than 140 degrees.At magnified imaging,the resolution is equivalent to 2.78 μm in object space,and the observed actual field of view is greater than 800 μm×700 μm.When used with a 26-inch display monitor,the high-magnification electronic endoscope can achieve 500×optical magnification,allowing for the observation of features at the cellular level.Currently,this product has successfully achieved mass production and has undergone multiple animal trials,demonstrating its wide range of potential applications and significant clinical value.

Objective:To clarify peripheral Th17 level in SSc patients and its correlation with disease.Methods:Chinese databases CNKI, CBM, Wanfang and VIP, and English databases PubMed, EMBASE, Web of Science, Cochrane Library and Science Direct were searched to collect a case-control study on the content of Th17 cells in peripheral blood of patients with SSc. The papers published when the database was first developed in 25 February 2021. Meta-analysis was conducted using Stata 12.0 software, and I2 and Egger tests were used to evaluate the heterogeneity and publication bias between studies. Results:A total of 26 case-controls were included in the study, including 1 160 patients with SSc and 778 healthy controls. Overall, the percentage of Th17 cells in SSc patients was higher than in healthy controls [SMD(95% CI)=1.85 (1.33, 2.38), P<0.001], which was most significant in IL-17 +Th17 concentration [SMD(95% CI)=1.88 (1.28, 2.48), P<0.001]. As for disease activity, the proportion of Th17 cells in active SSc patients was much higher than those of patients in remission [SMD(95% CI)=1.92 (1.12, 2.71), P<0.001]. SSc patients had a reduced Th17 level after receiving DMARDs treatment [SMD(95% CI)=-0.74 (-1.05, -0.42), P=0.029]. Conclusion:The number of Th17 cells increase significantly in the peripheral blood of patients with SSc, and is related to disease activity. DMARDs can be used to treat this disease by downregulating Th17 levels.

ObjectiveTo determine the influence of COVID-19 prevention and control on the epidemic characteristics and dynamics of notifiable infectious diseases in the first quarters， Zhejiang Province， and to explore more effective countermeasures against infectious diseases. MethodsDescriptive epidemiology was conducted to determine the change in notifiable infectious diseases during the prevention and control of COVID-19 in Zhejiang Province by retrieving the data of notifiable infectious diseases from 2017 to 2022 in the Chinese information system for disease control and prevention. Cumulative reported new cases of notifiable infectious diseases in the first quarters of 2017‒2019 were compared with that of 2020‒2022. ResultsA total of 546 753 cases of notifiable infectious diseases were newly reported in the first quarters of 2017‒2019， with an average incidence of 321.92/10⁵. In contrast， a total of 509 908 cases of notifiable infectious diseases were newly reported in the first quarters of 2020‒2022， during which the COVID-19 epidemic occurred， with an average incidence of 270.39/10⁵. The incidence in 2020‒2022 significantly declined by 51.53/10⁵， compared with that in 2017‒2019 （χ²=8 072.06， P<0.001）. In the first quarters of 2020‒2022， the average incidence of zoonotic diseases and vector-borne diseases decreased by more than 50%. In addition， the incidence of respiratory， enteric， blood-borne， and sexually transmitted diseases declined to certain degree. ConclusionThe decline in the newly reported cases of non-COVID-19 notifiable infectious diseases in the first quarters of 2020‒2022 indicates that the countermeasures against COVID-19 epidemic， such as multi-disease co-prevention， multi-sectoral collaboration， societal mobilization and personal hygiene and protection， may also decrease the incidence of multiple infectious diseases. It suggests the countermeasures are effective， which would provide evidence for routine prevention and control of infectious diseases in future.

Corona virus disease 2019 （COVID-19） has led to more than 500 million cases， including 6.19 million deaths. Mutated strains of SARS-CoV-2 （alpha， beta， gamma， delta and omicron） have successively emerged. Currently the omicron variant is gradually replacing the delta variant， driving a surge of cases in most countries including China， posing a great challenge to the prevention and treatment of COVID-19. In the face of the severe pandemic situation， a large number of non-medical volunteers are fighting on the front lines of the war against the pandemic and are vulnerable to exposure due to lack of professional knowledge. This paper introduces the routine skills training of volunteers and emergency response， aiming to provide behavioral guidance for non-medical volunteers in designated isolation facilities.

Stimulator of interferon genes (STING) is a cytosolic DNA sensor which is regarded as a potential target for antitumor immunotherapy. However, clinical trials of STING agonists display limited anti-tumor effects and dose-dependent side-effects like inflammatory damage and cell toxicity. Here, we showed that tetrahedral DNA nanostructures (TDNs) actively enter macrophages to promote STING activation and M1 polarization in a size-dependent manner, and synergized with Mn²⁺ to enhance the expressions of IFN-β and iNOS, as well as the co-stimulatory molecules for antigen presentation. Moreover, to reduce the cytotoxicity of Mn²⁺, we constructed a TDN-MnO₂ complex and found that it displayed a much higher efficacy than TDN plus Mn²⁺ to initiate macrophage activation and anti-tumor response both in vitro and in vivo. Together, our studies explored a novel immune activation effect of TDN in cancer therapy and its synergistic therapeutic outcomes with MnO₂. These findings provide new therapeutic opportunities for cancer therapy.

This study explored the correlation between color and chemical components of Chrysanthemi Indici Flos(CIF), aiming at providing a reference for its procurement, evaluation, and breeding. Colorimeter and ultra-performance liquid chromatograph(UPLC) were used to determine the color(lightness-shade chromaticity value L~*, red-green chromaticity value a~*, yellow-blue chromati-city value b~*) and chemical components(cynaroside, linarin, luteolin, apigenin, and chlorogenic acid) of 84 CIF germplasms, respectively. Diversity analysis, correlation analysis, regression analysis, and cluster analysis were performed. The results showed that the color and chemical components of CIF were diversified. Chlorogenic acid was in significantly positive correlation with L~* and b~* and significantly negative correlation with a~*. Cynaroside and grey relational grade γ_i of chemical components were in significantly po-sitive correlation with b~* and L~*, respectively, whereas linarin, luteolin, and apigenin had no significant correlation with L~*, a~*, or b~*. The 84 CIF germplasms were clustered into 4 clades. In addition, germplasms in clade Ⅲ had higher γ_i and total color value(E~*_(ab)) than those in other clades, with the best quality and color, and a germplasm with the highest quality, bright yellow color, and highest content of linarin was screened out in this clade. Thus, CIF with bright yellow color had high content of cymaroside and chlorogenic acid and thereby high quality. In summary, the color can be used to quickly predict the quality of CIF. Our results provided data for the evaluation of CIF quality by color and a reference for its procurement and breeding.
Chrysanthemum/chemistry* ; Luteolin/analysis* ; Chlorogenic Acid/analysis* ; Apigenin/analysis* ; Plant Breeding ; Excipients ; Chromatography, High Pressure Liquid/methods*

Objective To investigate the imaging features of dysplastic nodules with a focus of hepatocellular carcinoma ( DN-HCC ) on contrast-enhanced ultrasound ( CEUS ) and to improve the diagnostic accuracy . Methods The clinical data of 60 patients and CEUS imaging of 62 hepatic nodules [DN-HCCs , n =54 ;dysplastic nodules (DN) , n =8] pathologically proved were reviewed retrospectively . According to Contrast Enhanced Ultrasound Liver Imaging Reporting and Data System (CEUS LI-RADS) , the lesions were categorized . Results Significantly different CEUS patterns between DN-HCCs and DNs were observed ( P < 0 .05) . During the arterial phase ,54 DN-HCC lesions showed various enhancement patterns [ hypervascular ,59 .3％ ( 32/54 ) ;nodule-in-nodule ,9 .3％ ( 5/54 ) ;isovascular ,13 .0％ ( 7/54 ) and hypovascular ,18 .5％ (10/54)] . Of the 54 DN-HCC lesions ,44 .4％ (24/54) showed washout during the late phase .Of the 8 DN lesions ,62 .5％ (5/8) showed iso-enhancement during the arterial phase ,25％ (2/8) showed hypo-enhancement ,and 12 .5％ (1/8) showed hyper-enhancement . No DN lesion showed washout during the late phase .According to CEUS LI-RADS (LR) algorithm ,27 .8％ (15/54) DN-HCCs were LR-5 ,46 .3％ (25/54) DN-HCCs were LR-4 ,25 .9％ (14/54) DN-HCCs and 100％ (8/8) DNs were LR-3 . Regarding hyper-enhancement ( including local hyper-enhancement ) during the arterial phase or hypo-enhancement (including local hypo-enhancement) during the late phase as the diagnostic standard of DN-HCC , the diagnostic sensitivity , specificity and accuracy value were 83 .3％ , 87 .5％ and 83 .9％ , respectively . Conclusions The imaging features of hyper-enhancement during the arterial phase or hypo-enhancement during the late phase on CEUS are useful to diagnose DN-HCCs .

Objective To evaluate the correlation and consistency of dynamic three-dimensional contrast-enhanced ultrasonography ( 3D-CEUS ) and two-dimensional contrast-enhanced ultrasonography (2D-CEUS) in the time-intensity curve ( TIC) parameters of quantitative analysis in liver neoplasms. Methods Thirty patients were examined with 2D-CEUS and dynamic 3D-CEUS.The dynamic raw data were analyzed by quantitative analysis software. The regions of interest were manually selected around the entire lesion;TIC curves were generated and fitted respectively. Quality of fit ( QOF) was used to evaluate the degree of fit between the fitted curve and the initial ccoefficients of S,PI and AUC were 0.92,0.72 and urve. The corresponding 2D-CEUS and 3D-CEUS quantitative parameters of the same lesion were compared,including peak intensity ( PI),slope ( S),area under curve (AUC),time to peak (TTP) and mean transit time (MTT). The correlation of the intensity-related quantitative parameters and the consistency of the time-related quantitative parameters were analyzed between the two kinds of CEUS. Results The consistency of time related quantitative parameters,including MTT and TTP,were 0.97 and 0.96,and the correlation were 0.94 and 0.93. The correlation 0.65,respectively. Conclusions The quantitative results of 3D-CEUS are stable and reliable,and have fair concordance with 2D-CEUS. Dynamic 3D-CEUS can be used for clinical evaluation of the blood perfusion of liver neoplasms.