ObjectiveThe contamination of foodborne pathogens in ready-to-eat fruits and vegetables in Shanghai was analyzed to provide a scientific basis for food safety， risk assessment and related supervision. MethodsFrom June to September 2021， a total of 143 batches of12 kinds of ready-to-eat fruits and vegetables such as lettuce， chicory， and cherry tomatoes were collected from farmers’ markets， supermarkets， and e-commerce platforms. The total number of bacterial colonies， Salmonella， Listeria monocytogenes， Staphylococcus aureus， Cronobacter spp. and Shiga toxin-producing Escherichia coli in the samples were tested according to National Food Contamination and Harmfulness Risk Monitoring Manual. ResultsAmong the 143 batches， foodborne pathogens were detected in 68 batches， with a total detection rate of 47.55% （68/143）. A total of 79 strains of foodborne pathogens were detected. The detection rate of Staphylococcus aureus was the highest （32.87%， 47/143）， followed by Cronobacter spp. （20.98%， 30/143）， Salmonella （0.70%， 1/143）， Listeria monocytogenes （0.70%， 1/143）， Shiga toxin-producing Escherichia coli （0.00%）. Furthermore， the detection rate was higher in different ready-to-eat fruits and vegetables： chicory （17.33%）， cucumber （17.14%）， cherry tomatoes （16.00%）， and honeydew melon （15.38%）， respectively. Meanwhile， the contamination rate of pathogens in ready-to-eat fruits and vegetables from farmers’ markets， supermarkets， and e-commerce platforms was relatively high. ConclusionReady-to-eat fruits and vegetables in Shanghai are contaminated by foodborne pathogens. The prevention and control of the contamination of post-harvest fruits and vegetables should be strengthened to reduce the risk of foodborne disease outbreaks.

Objective:To investigate the influencing factors of recurrence after radical resection of middle and low rectal cancer, and to establish a prediction model based on magnetic resonance imaging (MRI) measurement of perirectal fat content and investigate its application value.Methods:The retrospective cohort study was constructed. The clinicopathological data of 254 patients with middle and low rectal cancer who were admitted to Tianjin Union Medical Center from December 2016 to December 2021 were collected. There were 188 males and 66 females, aged (61±9)years. All patients underwent radical resection of rectal cancer and routine pelvic MRI examina-tion. Observation indicators: (1) follow-up and quantitative measurement of perirectal fat content; (2) factors influencing tumor recurrence after radical resection of middle and low rectal cancer; (3) construction and evaluation of the nomogram prediction model of tumor recurrence after radical resection of middle and low rectal cancer. Measurement data with normal distribution were represented as Mean± SD, and measurement data with skewed distribution were represented as M(rang) and M( Q1, Q2). Count data were described as absolute numbers. Univariate and multivariate analyses were conducted using the COX regression model. The rms software package (4.1.3 version) was used to construct the nomogram and calibration curve. The survival software package (4.1.3 version) was used to calculate the C-index. The ggDCA software package (4.1.3 version) was used for decision curve analysis. Results:(1) Follow-up and quantitative measurement of perirectal fat content. All 254 patients were followed up for 41.0(range, 1.0?59.0)months after surgery. During the follow-up period, there were 81 patients undergoing tumor recurrence with the time to tumor recurrence as 15.0(range, 1.0?43.0)months, and there were 173 patients without tumor recurrence. The preoperative rectal mesangial fascia envelope volume, preoperative rectal mesangial fat area, preoperative rectal posterior mesangial thickness were 159.1(68.6,266.5)cm3, 17.0(5.1,34.4)cm2, 1.2(0.4,3.2)cm in the 81 patients with tumor recurrence, and 178.5(100.1,310.1)cm3, 19.8(5.3,40.2)cm2 and 1.6(0.3,3.7)cm in the 173 patients without tumor recurrence. (2) Factors influencing tumor recurrence after radical resection of middle and low rectal cancer. Results of multivariate analysis showed that poorly differentiated tumor, tumor pathological N staging as N1?N2 stage, rectal posterior mesangial thickness ≤1.43 cm, magnetic resonance extra mural vascular invasion, tumor invasion surrounding structures were independent risk factors of tumor recurrence after radical resection of middle and low rectal cancer ( hazard ratio=1.64, 2.20, 3.19, 1.69, 4.20, 95% confidence interval as 1.03?2.61, 1.29?3.74, 1.78?5.71, 1.02?2.81, 2.05?8.63, P<0.05). (3) Construction and evaluation of the nomogram prediction model of tumor recurrence after radical resection of middle and low rectal cancer. Based on the results of multivariate analysis, the tumor differentiation, tumor pathological N staging, rectal posterior mesangial thickness, magnetic resonance extra mural vascular invasion, tumor invasion surrounding structures were included to construct the nomogram predic-tion model of tumor recurrence after radical resection of middle and low rectal cancer. The total score of these index in the nomogram prediction model corresponded to the probability of post-operative tumor recurrence. The C-index of the nomogram was 0.80, indicating that the prediction model with good prediction accuracy. Results of calibration curve showed that the nomogram prediction model with good prediction ability. Results of decision curve showed that the prediction probability threshold range was wide when the nomogram prediction model had obvious net benefit rate, and the model had good clinical practicability. Conclusions:Poorly differentiated tumor, tumor pathological N staging as N1?N2 stage, rectal posterior mesangial thickness ≤1.43 cm, magnetic resonance extra mural vascular invasion, tumor invasion surrounding structures are independent risk factors of tumor recurrence after radical resection of middle and low rectal cancer. Nomogram prediction model based on MRI measurement of perirectal fat content can effectively predict the probability of postoperative tumor recurrence.

Objective:To establish an in vitro capsular bag model and compare the inhibitory effects of different 360° square-edge intraocular lens (IOL) on lens epithelial cells (LECs) migration. Methods:In vitro capsular bag model with posterior capsule opacification (PCO) was established using Transwell compartment, cell climbing slices, human collagen type Ⅳ, and IOL.The models were divided into Plate-loop HydroSmart group, C-loop HydroSmart group, and C-compensation-loop Hydrophobic group according to the different square-edge IOL implanted.A blank control group was set using the Transwell compartment without IOL.The early PCO pathological manifestations in lens epithelial cell line SRA01/04 cultured in the Transwell compartment were observed with an inverted microscope.The cell morphology in different groups was observed by hematoxylin and eosin staining.The cell counting and cell migration inhibition rate of anterior capsule and posterior capsule were calculated by Transwell assay and cell-exclusion zone assay, respectively. Results:The early pathological characteristics of PCO, such as early Soemmering ring and small Elschnig pearl, could be found in cells in the in vitro capsular bag model after 48-hour culture.The migrating cells in model groups were fibrous.No changes mentioned above were found in blank control group.The number of migrating cells in the anterior capsule of Plate-loop HydroSmart group, C-loop HydroSmart group, C-compensation-loop Hydrophobic group was 18.80±5.53, 24.67±9.80, and 34.47±10.80, respectively, and the number of migrating cells in the optical area of the posterior capsule of the three groups was 56.43±9.00, 162.20±16.38, and 121.30±12.01, respectively.The cell migration inhibition rate in the anterior capsule of Plate-loop HydroSmart group, C-loop HydroSmart group, C-compensation-loop Hydrophobic group was (92.02±1.94)%, (89.76±3.10)%, (86.27±4.54)%, respectively, and the cell migration inhibition rate in optical area of the posterior capsule of the three groups was (91.60±3.65)%, (70.14±5.35)%, (78.43±3.48)%, respectively.The number of migrating cells in the anterior capsule was lower and the cell migration rate inhibition was higher in Plate-loop HydroSmart group than C-compensation-loop Hydrophobic group, with significant differences (both at P<0.05). The number of migrating cells in the optical area of the posterior capsule and the cell migration inhibition rate was greater than those of C-loop HydroSmart group and C-compensation-loop Hydrophobic group, showing statistically significant differences (all at P<0.001). Conclusions:The in vitro capsular bag model can be used in PCO research.Compared with C-loop HydroSmart IOL and C-compensation-loop Hydrophobic IOL, Plate-loop HydroSmart IOL can more effectively inhibit the migration of LECs to the optical area of the posterior capsule.

Objective:To construct the molecular transmission network of human immunodeficiency virus type 1 (HIV-1) epidemic strains in northern Zhejiang Province (Jiaxing City and Huzhou City) and to explore the HIV-1 transmission characteristics in this region.Methods:A total of 371 newly diagnosed human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS) patients in Jiaxing City and Huzhou City in 2017 were included as study subjects, and the blood samples were collected and the basic demographic and epidemiological information were obtained. RNA in plasma was extracted, and the pol region gene sequence was amplified by reverse transcriptase polymerase chain reaction (RT-PCR) and nested polymerase chain reaction (PCR) to construct phylogenetic tree for identifying subtypes. The pairwise genetic distances were calculated, and the optimal threshold of genetic distance was selected, and finally the molecular transmission network was constructed. Chi-square test was used for statistical analysis. Results:The pol region gene sequences of 336 samples were successfully obtained, and 11 subtypes were detected, mainly including circulating recombinant form (CRF)07_BC (40.8%, 137/336) and CRF01_AE (31.2%, 105/336). Based on the 1.0% genetic distance threshold, the molecular transmission network of HIV-1 was plotted. A total of 38 transmission clusters (cluster sizes ranging from two to 28) including 119 patients were found, with males predominantly (82.4%, 98/119) and most of the patients aged over 40 (include 40) years old (52.9%, 63/119), mainly infected with CRF07_BC subtype (57.1%, 68/119) and CRF01_AE (24.4%, 29/119). The clustering rate of CRF07_BC (49.6%, 68/137) was significantly higher than that of CRF01_AE (27.6%, 29/105), the difference was statistically significant ( χ2=5.27, P=0.022). Two large clusters C1 (28 cases) and C2 (11 cases) were identified, the majority of which were men who have sex with men (17 cases and seven cases, respectively). High-risk cases generally sought sexual partners in local or nearby cities through mobile phone dating software, of which the infected sequences mostly had high homology with other economic developed regions (Guangdong Province, Beijing City and Hangzhou City, etc.). Conclusions:The HIV-1 subtypes are diverse in Jiaxing City and Huzhou City, mainly CRF07_BC and CRF01_AE. The HIV-1 transmission networks are complex, among which high-risk cases may be the key factor leading to the HIV-1 epidemic in the region. Therefore, it is urgent to deepen the transmission network monitoring and formulate timely precise intervention and prevention strategies.

OBJECTIVE：To learn from the experience of foreign listed chimeric antigen receptor T lymphocyte （CAR-T） products in signing risk sharing agreements in medical insurance access ，so as to provide references for relevant decisions of medical insurance departments in China. METHODS ：Taking 9 risk sharing agreements of CAR-T products marketed in the United Kingdom，France，Italy and Germany as samples ，the international experience of medical insurance payment of CAR-T products were analyzed from six dimensions ，such as agreement types ，monitoring indicators ，data collection metho ds，agreement periods ， payment conditions and payment methods. Some suggestions were put forward for the medical insurance access of these products in China. RESULTS & CONCLUSIONS ：Four sample countries generally signed risk sharing agreements of medical insurance access （financial agreement and performance-based agreement ）with pharmaceutical enterprises ；the indicators such as progressive disease and progression-free survival were collected by using data collection system or clinical research data ，so as to monitor the efficacy and safety of CAR-T products. The agreement periods and payment conditions were determined according to different agreement types；“medical insurance advance payment ”or“pharmaceutical enterprise advance payment ”combined with “staged payments ” were adopted for risk control. Solving the risk of medical insurance funds caused by “efficacy uncertainty ”is the core issue of CAR-T product access. The induction of risk sharing agreements may be the way to solve this problem ，and the scientific design of the various elements of risk sharing agreements is a prerequisite to ensure that the agreement is operational.

Objective:To investigate the characteristics of subtype diversity and transmission on HIV-1 among 12 to 30 years old student MSM in Zhejiang province.Methods:A total of 290 newly diagnosed HIV infected student MSM were selected as the research objects for molecular studies on HIV, in Zhejiang province during 2013 to 2015. Data on epidemiology and plasma samples of these people were collected. HIV-1 nucleotide sequences of pol gene regions were amplified using the RT-PCR/nested PCR method and sequenced. Phylogenetic analysis was performed to determine the HIV-1 genotypes. Characteristics of transmission mode among these cases were also analyzed. Results:A total of 290 cases, 50.3 % were diagnosed in Hangzhou and 81.0 % had college or above degrees. 178 sequences including 10 subtypes, were obtained, with the main subtypes as CRF01_AE (49.4 %, 88/178) and CRF07_BC (39.3 %, 70/178). A total of 18 molecular transmission clusters were formed (42 cases, cluster size from 2 to 4), with the proportions of clusters as 23.6 % (42/178). 61.9 % (26/42) of student MSM with their schools located in the same district within the transmission clusters. Their sexual partners would include both student MSM and non-student MSM. The proportion of clusters among middle school students was 38.2 % (13/34), higher than that of college students (20.1 %, 29/144) ( χ2=4.996, P<0.05). Conclusions:The HIV-1 subtypes of student MSM in Zhejiang province appeared diversity, which indicated with the diversity of sources of infection. The geographical distribution of cluster cases is relatively centralized. In order to effectively control the spread of AIDS, more attention should be paid to the sexual partners involved and to specific programs on intervention.

Collectively migrating tumor cells have been recently implicated in enhanced metastasis of epithelial malignancies. In oral squamous cell carcinoma (OSCC), v integrin is a crucial mediator of multicellular clustering and collective movement ; however, its contribution to metastatic spread remains to be addressed. According to the emerging therapeutic concept, dissociation of tumor clusters into single cells could significantly suppress metastasis-seeding ability of carcinomas. This study aimed to investigate the anti-OSCC potential of novel endostatin-derived polypeptide PEP06 as a cluster-dissociating therapeutic agent . Firstly, we found marked enrichment of v integrin in collectively invading multicellular clusters in human OSCCs. Our study revealed that metastatic progression of OSCC was associated with augmented immunostaining of v integrin in cancerous lesions. Following PEP06 treatment, cell clustering on fibronectin, migration, multicellular aggregation, anchorage-independent survival and colony formation of OSCC were significantly inhibited. Moreover, PEP06 suppressed v integrin/FAK/Src signaling in OSCC cells. PEP06-induced loss of active Src and E-cadherin from cell-cell contacts contributed to diminished collective migration of OSCC . Overall, these results suggest that PEP06 polypeptide 30 inhibiting v integrin/FAK/Src signaling and disrupting E-cadherin-based intercellular junctions possesses anti-metastatic potential in OSCC by acting as a cluster-dissociating therapeutic agent.

Objective In order to evaluate that whether Pluronic P85 coated poly(butylcyanoacrylate) nanoparti-cles was able to deliver antiepileptic drug phenytoin into the brain va bypassing mesial temporal lobe epilepsy (MTLE)-induced Pgp in a rat model of MTLE. Methods The rat model of MTLE, induced by li-pilocarpine, was divided in-to two groups (6 for nanoparticle drug group and 7 for PHT drug group). Immunohistochemistry assay was performed to detect Pgp expression at the hippocampus. Nanoparticles were prepared by interfacial polymerization method. Dialysate samples of brain were collected at 30, 60, 120, 180, 240 and 300 min after drug administration by microdialysis tech-nology. Samples were analyzed by high performance liquid chromatography (HPLC). Results The area under the curve (AUC) ratio of brain/plasma in Nanoparticle drug group was 0.370.10 which was significantly higher compared with 0.190.06 in conventional PHT drug group (P<0.05). The Pgp immunopositive area, as assessed by analysis of labeled surface area, was higher in the DG, CA3 and CA1 sector in the hippocampus of MTLE rats when compared to the normal rats. Conclusions Pluronic P85 coated PBCA nanoparticles can significantly deliver PHT into brain via bypassing MTLE-induced Pgp in a rat model of MTLE.

Objective To understand the characteristics of distribution on HIV-1 subtypes and the transmission clusters in Yiwu in Zhejiang province.Methods A cross-sectional study of molecular epidemiology was carried out on newly reported H1V/AIDS cases in Yiwu.RNA was extracted from 168 plasma samples,followed by RT-PCR and nest-PCR for pol gene amplification,sequencing,phylogenetic tree construction used for analyzing the subtypes and transmission clusters.Mutations on drug resistance was analyzed by CPR 6.0 online tool.Results Subjects were mainly males (86.3％,145/168),with average age as (39.1 ± 13.4) years old and most of them were migrants (66.7％,112/168).The major routes of transmission included homosexual (51.2％,86/168) and heterosexual (48.8％,82/168) contacts.The rate of success for sequence acquisition was 89.9％ (151/168).The dominant subtypes showed as CRF01_AE (74,49.0％) and CRF07_BC (64,42.4％),followed by CRF08_BC (5,3.3％),CRF55_01B (3,2.0％),each case of subtype B,CRF45_cpx,CRF59_01B,CRF85_BC and URF (B/C).CRF45_cpx and CRF85_BC were discovered the first time in Zhejiang province.Twenty-six transmission clusters involving 65 cases were found,with the total clustered rate as 43.0％ (65/151),in which the CRF01_AE clustered rate appeared as 54.1％ (40/74),higher than that of CRF07_BC (21/64,32.8％).The average size of cluster was 2.5 cases/cluster,with average size of cluster in CRF01_AE patients infected through heterosexual transmission as the largest (3.5 cases/cluster).The prevalence of transmitted drug resistance was 4.6％ (7/151).Seven cases with surveillance drug resistant mutations (SDRM) were found,including 5 cases of M46L (3.3％),and one case of F77L or Y181C.Conclusion HIV genetic diversity and a variety of transmission clusters had been noticed in this study area (Yiwu).Programs on monitoring the subtypes and transmission clusters should be continued and strengthened.

Objective To express the receptor binding domain (RBD) protein of the Middle East respiratory syndrome coronavirus (MERS-CoV) and to characterize the antigenicity of the purified recombi-nant protein. Methods The codon-optimized gene encoding the RBD protein of MERS-CoV was synthesized and then cloned into the pET30a ( +) vector to construct the recombinant expression plasmid. The trans-formed E. coli BL21 (DE3) strains carrying expression plasmid were induced by IPTG under different condi-tions. The expressed products were purified by using nickel affinity chromatography and further analyzed by SDS-PAGE and Western blot assay. Indirect ELISA was performed to analyze the antigenicity and specificity of RBD proteins expressed in prokaryotic expression systems in human serological test. Results The recom-binant RBD proteins were mainly expressed as conclusion body in an optimal induction condition of 37℃ and 0. 5 mmol/ L IPTG for 4 h. The high purified recombinant RBD proteins were obtained through denaturation and renaturation with a relative molecular mass of about 29×103 . Results of the Western blot assay showed that the recombinant RBD proteins could have specific reaction with the serum samples collected form mice with MERS-CoV infection. Indirect ELISA revealed that the RBD proteins expressed in the prokaryotic ex-pression system showed better sensitivity and specificity in the detection of antibodies against MERS-CoV in human serum samples. Conclusion This study reported the prokaryotic expression and purification of RBD protein of MERS-CoV for the first time, which might pave the way for further investigation on immunological detection of MERS-CoV and development of vaccines against MERS-CoV infection.