[Role of blood markers in predicting the failure of prosthesis removal and antibiotic-loaded bone cement spacer implantation for treatment of periprosthetic joint infection].

Objective: To investigate the value of inflammation,coagulation and nutrition markers in predicting the failure of prosthesis removal and antibiotic-loaded bone cement spacer implantation for treatment of periprosthetic joint infection(PJI). Methods: A retrospective study was conducted on 70 patients who undertook prosthesis removal and antibiotic-loaded bone cement spacer implantation due to PJI from June 2016 to October 2020 in the Department of Orthopedics,Henan Provincial People's Hospital. There were 28 males and 42 females,aged (65.5±11.9) years (range: 37 to 88 years). Patients were divided into two groups as the successful group and the failed group depended on whether reinfection occurred after prosthesis removal and antibiotic-loaded bone cement spacer implantation at the last follow up. Patient demographics,laboratory values (C-reactive protein (CRP),erythrocyte sedimentation rate (ESR),ESR and CRP ratio (ESR/CRP),white blood cell count(WBC),platelet count(PLT),hemoglobin(HB),total lymphocyte count(TLC),albumin、fibrinogen(FIB),CRP and albumin ratio (CAR),prognostic nutritional index(PNI)),and reinfection rates were assessed. Comparison between groups was conducted by the independent sample t test or χ2test. Receiver operating characteristic (ROC) curve was plotted,and the area under the curve (AUC),optimal diagnostic threshold,sensitivity,and specificity were analyzed to predict the failure of prosthesis removal and antibiotic-loaded bone cement spacer implantation. Results: All patients were followed up for at least two years,and the follow-up time was (38.4±15.2) months (range: 24 to 66 months). Fifteen patients suffered failure after prosthesis removal and antibiotic-loaded bone cement spacer implantation,while the other 55 patients succeeded. The overall failure rate of prosthesis removal and antibiotic-loaded bone cement spacer implantation in PJI treatment was 21.4%. Level of preoperative CRP ((35.9±16.2)mg/L),PLT ((280.0±104.0)×109/L) and CAR (1.3±0.8) in successful group were lower than CRP ((71.7±47.3)mg/L),PLT ((364.7±119.3)×109/L) and CAR (2.5±2.0) in failed group (all P<0.05).Whereas,level of preoperative ESR/CRP (3.3±3.1), Albumin ((35.3±5.2)g/L) and PNI (43.6±6.2) in successful group were higher than ESR/CRP (1.6±1.4),Albumin ((31.3±4.8)g/L) and PNI (39.2±15.1) in failed group (all P<0.05). AUC of ROC curve,optimal threshold value,sensitivity and specificity of CRP,ESR/CRP, PLT, Albumin,CAR and PNI for the predicting failure of prosthesis removal and antibiotic-loaded bone cement spacer implantation were 0.776(95%CI:0.660 to 0.867),35.4 mg/L,86.7%,67.3%;0.725(95%CI:0.605 to 0.825),1.0,60.0%,78.2%;0.713(95%CI:0.593 to 0.815),253,93.3%,47.3%;0.721(95%CI:0.601 to 0.822),35.7,93.3%,49.1%;0.772(95%CI:0.656 to 0.863),1.1,86.7%,67.3%;0.706(95%CI:0.585 to 0.809),45.7,100%,41.8% respectively. Conclusion: In patients with PJI,CRP>35.4,ESR/CRP≤1.0 and CAR>1.1 could predict the failure of prosthesis removal and antibiotic-loaded bone cement spacer implantation.

[Mechanism of advanced glycation end products inhibiting the proliferation of peripheral blood mononuclear cells and osteoblasts in rats].

OBJECTIVE: To explore the mechanism of nuclear factor-kappa B (NF-κB), phosphatidylinositol 3-kinase (PI3K)/protein kinase B(PKB/Akt) and mitogen-activated protein kinase (MAPK) signaling pathways after intervention of advanced glycosylation end products (AGEs) in peripheral blood mononuclear cells (PBMCs) and osteoblasts (OB) in rats, so as to provide certain experimental basis and theoretical basis for further research on the clinical treatment of periodontal tissue inflammation caused by diabetes mellitus. METHODS: AGEs were prepared, PBMCs and OB were isolated and cultured in vitro. CCK-8 was used to detect the cell viability intervened by different concentrations and time of AGEs. Western blot and qRT-PCR were used to detect the expression changes of genes related to NF-κB, PI3K/PKB and MAPK signaling pathways. RESULTS: OB and PBMCs were successfully isolated and cultured in vitro. The activity of PBMCs and OB cells was significantly correlated with the concentration, time and interaction of AGEs. With the increase of AGEs concentration and time, the activity of PBMCs and OB cells significantly decreased (P < 0.001). AGEs stimulation significantly increased the expression of NF-κB in PBMCs and the contents of tumor necrosis factor α(TNF-α), interleukin-1ß(IL-1ß) (P < 0.01). TNF-α, IL-1ß levels were significantly reduced after inhibition of NF-κB pathway (P < 0.01). NF-κB p65, JNK, and p38 phosphorylated and non-phosphorylated proteins increased significantly after AGEs stimulation of OB (P < 0.05). The phosphorylated protein expression of IκB was significantly increased, while the expression of non-phosphorylated protein was decreased (P < 0.01).The expressions of NF-κB p65, JNK, and IκB were significantly increased at the mRNA levels, and the expressions of IκB mRNA were significantly decreased (P < 0.05). There was no difference in the expression of Akt in either phosphorylated or non-phosphorylated proteins or at the mRNA level (P>0.05). With the addition of MAPK signaling pathway inhibitors, the phosphorylation and non-phosphorylated protein expressions of NF-κB p65, p38 and JNK were significantly reduced, and the phosphorylated protein of IκB was significantly decreased and the non-phosphorylated protein was significantly increased compared with the group with AGEs alone (P < 0.05). The results of qRT-PCR showed that the expression of IκB increased significantly after the addition of the JNK pathway blocker (P < 0.05), and the expression of NF-κB p65, p38 and JNK decreased, but the difference was not significant (P>0.05). While NF-κB p65, p38 and JNK were significantly decreased and IκB was significantly increased in the AGEs group after the addition of the p38 pathway blocker (P < 0.05). At this time, there was still no significant change in the expression of Akt at the protein level and mRNA level (P>0.05). CONCLUSION: AGEs inhibit the proliferation of PBMCs and OB, and the NF-κB and MAPK pathways are likely involved in regulating this process, but not the PI3K/PKB pathway.

[Investigation on Norovirus prevalence in catering companies and train station in Beijing during non-epidemic season in 2019].

Objective: To study the prevalence of Norovirus infection among kitchen workers in Beijing, and the contamination status of Norovirus in catering companies and train station. Methods: A cross-sectional survey was conducted to collect anal swab specimens and environmental specimens from catering companies in 16 districts of Beijing and in 3 big train stations. Norovirus nucleic acid was detected by fluorescence quantitative PCR. The contamination status of Norovirus in the environment and the asymptomatic infection status of kitchen workers was analyzed in this study. Results: A total of 650 catering companies were investigated. 1 302 anal swabs or stool specimens and 2 600 environmental swabs were collected and tested. Among the 644 catering companies out of train stations, 1 290 anal swabs or stool specimens and 2 576 environmental swabs were collected and tested. The asymptomatic infection rate of Norovirus was 0.85% (11/1 290) among kitchen workers of the catering companies out of the train stations, while the positive rate of norovirus contamination in the environment was 0.04% (1/2 576). Norovirus was not detected in the specimens collected from the kitchen workers and the environment of the catering companies in train stations. Conclusion: During the non-epidemic season of Norovirus in 2019, the infection rate of Norovirus among kitchen workers in Beijing is low, and the environment is contaminated by Norovirus.

[Comparative study on metagenomics of esophageal flora in elderly and middle-aged esophageal squamous cell carcinoma patients].

Objective: To explore the flora characteristics and differences of esophageal tissues between elderly esophageal squamous cell carcinoma (ESCC) patients and young and middle-aged ESCC patients, so as to assist in studying the potential biomarkers of elderly ESCC patients. Methods: In this study, a retrospective study was adopted. 72 ESCC patients diagnosed in Taihe Hospital, Shiyan City, Hubei Province from July 2018 to July 2019 were selected, including 49 patients in the elderly group (≥ 60 years old, 40 males and 9 females), 23 patients in the young and middle-aged group (<60 years old, 21 males and 2 females). In the same period, 20 healthy persons without abnormal gastroscopy in endoscopy center were selected as the control group (aged 35-78 years old, median age 57 years old, 16 males and 4 females). The genomic DNA was extracted from the affected esophageal tissues of patients with ESCC and the middle esophageal samples of the control group. The V4 hypervariable region of bacterial 16SrRNA gene sequence was amplified. Illumina HiSeq sequencing technology was adopted. The flora characteristics of elderly, young and middle-aged ESCC patients was compared and analyzed. QIIME and Rstudio software were used to analyze the sequence data, and nonparametric Kruskal-Wallis test or Wilcoxon rank sum test were used for statistical methods. Results: Shannon index [5.17 (4.53, 5.95) vs. 4.79 (3.74, 5.97)], Simpson index [0.94 (0.91, 0.96) vs. 0.92 (0.83, 0.96)] and Chao1 index [343.55 (259.76, 570.59) vs. 329.16 (268.88, 648.00)] were similar in flora of two groups, and there was no significant difference (Z=-0.791, -1.057, -0.380, all P>0.05). There was no significant difference in ß-diversity between the elderly group and the young and middle-aged group (PC1=19.14%, PC2=6.95%, PPC1=0.67, PPC2=0.42). At the phyla level, the top 5 phyla in abundance were as follows: Firmicutes, Bacteroidetes, Proteobacteria, Actinobacteria and Fusobacteria in the young and middle-aged group, while the top 5 phyla in abundance were as follows: Firmicutes, Bacteroidetes, Proteobacteria, Fusobacteria and Actinobacteria in the elderly group; the significant difference between the two groups was Fusobacteria (Q=0.596, P<0.05). At the genus level, the top 5 genera in the young and middle-aged group in abundance were as follows: Prevotella, Bacteroides, Streptococcus, Selenomonas and Veillonella. In the elderly group, Prevotella, Bacteroides, Streptococcus, Selenomonas and Haemophilus were the top 5 in abundance, and there were significant difference in Fusobacterium between the two groups (Q=0.938, P<0.05). PICRUSt function prediction showed that the abundance of Aminoacyl.tRNA.biosynthesis, Nucleotide.excision.repair, RNA.polymerase, Ribosome, Clavulanic.acid.biosynthesis, Photosynthesis and Photosynthesis. proteins in the elderly group were lower than those in the young and middle-aged group (all Q=0.734, P<0.05). Conclusion: There is no significant difference in α-diversity and ß-diversity between elderly ESCC patients and young and middle-aged patients, but the abundance of Fusobacterium flora increased.

[Analysis of pathogenic composition and clinical characteristics of viral acute gastroenteritis in children under five years old in Beijing].

Objective: To understand the epidemiological characteristics and clinical features of rotavirus-, norovirus-, adenovirus-and astrovirus-associ ated acute gastroenteritis in children under 5 years old in Beijing from Octorber, 2015 to March, 2017. Methods: In the intestinal clinic of 6 hospitals in 6 districts of Beijing, information and stool samples of the first 30 patients with acute gastroenteritis who are under the age of 5 years are collected monthly.Rotavirus, norovirus, adenovirus and astrovirus are identified by PCR.Descriptive epidemiological method was used to describe the epidemiological characteristics of diarrhea caused by rotavirus, norovirus, adenovirus and astrovirus in Beijing. One-way analysis of variance was used to analyze the Vesikari clinical severity score of of acute gastroenteritis caused by each virus. Unconditional logistic regression analysis was used to analysis the associated factors of clinical features. Results: Of the 2 052 samples, 709 (34.6%) were non-mixed infections: the positive rate of rotavirus, norovirus, adenovirus and astrovirus were 20.0%, 7.5%, 4.2% and 2.9%, respectively. A total of 135 cases (6.6%) were mixed infection. The mean and standard deviation of Vesikari clinical severity score was 8.0±3.1 for rotavirus associated acute gastroenteritis, which was significantly higher than norovirus (6.4±2.4, P<0.001), adenovirus (6.2±2.1, P<0.001) and astrovirus (6.1±2.0, P<0.001). The comparison of clinical features showed that compared with astrovirus, the children under 5 years old infected with rotavirus were more likely to have a diarrhea ≥5 days (OR=3.334), have vomiting ≥3 times within one day (OR=8.788), have vomiting≥1 day (OR=3.963), have a Vesikari clinical severity score ≥11 severe cases (OR=13.194). Norovirus infected cases were prone to have vomiting≥3 times in 1 day (OR=5.710).Adenovirus infected cases were prone to have a diarrhea≥5 days (OR=2.616). When using rotavirus as a reference, children under 5 years of age were less likely to develop fever≥38.4 ℃ after infection with norovirus (OR=0.397) or adenovirus (OR=0.280). Conclusions: The results of this study showed that the characteristics of acute gastroenteritis caused by different viruses are different. The clinical symptoms caused by rotavirus are more serious. Children under 24 months of age are at high risk of rotavirus infection. Effective preventive measures such as vaccination should be taken as soon as possible.

Simvastatin monotherapy as a potential option for statin-associated muscle symptoms: a case report.

WHAT IS KNOWN AND OBJECTIVES: Choosing an alternative statin is recommended when managing statin-associated muscle symptoms (SAMS) and new hydrophilic statins are often suggested. We report on a case of statin-associated muscle damage that was successfully managed by simplifying the patient's combination therapy with simvastatin-ezetimibe to simvastatin alone. CASE SUMMARY: The patient experienced SAMS when he was successively treated with atorvastatin, rosuvastatin, Xuezhikang capsule and combined simvastatin/ezetimibe therapy. However, the patient tolerated simvastatin therapy well even at a dose of 40 mg/day. WHAT IS NEW AND CONCLUSION: Our case suggests that patients with SAMS who are intolerant to a wide variety of statins may be successfully managed with simvastatin monotherapy.

Pre-B-cell colony-enhancing factor is markedly elevated in childhood hemophagocytic lymphohistiocytosis.

Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening syndrome involving a final common pathway of hypercytokinemia, in which tumor necrosis factor (TNF)-α, interferon (IFN)-γ, and soluble interleukin 2-receptor-alpha (sIL-2Rα) are the key cytokines. Pre-B-cell colony-enhancing factor (PBEF) is an inflammatory cytokine involved in several inflammatory diseases. However, its role in HLH is unknown. In this study, we examined the role of PBEF in HLH. Plasma was collected from 22 children with HLH and 14 healthy children. The concentrations of plasma PBEF, TNF-α, IFN-γ, and sIL-2Rα were determined using an enzyme-linked immunosorbent assay. All clinical data were derived from medical records. In the acute phase, children with HLH had much higher PBEF, TNF-α, IFN-γ, and sIL- 2Rα levels than did healthy children (P < 0.05). After treatment, 13 HLH children improved and PBEF, TNF-α, and IFN-γ levels decreased to normal levels (P < 0.05); sIL-2Rα levels also decreased (P < 0.05), but remained above the normal level (P < 0.05). Two patients were lost to follow-up, while 7 patients showed a bad response to therapy and eventually died, showing high PBEF levels above those of the survivors (P < 0.01). PBEF level was significantly positively correlated with TNF-α, IFN-γ, sIL-2Rα, serum ferritin, and triglycerides (all P < 0.05), and was negatively correlated with fibrin (P < 0.05). PBEF appears to be involved in the inflammatory process of HLH, and elevated PBEF is related to disease activity. We are currently evaluating the role of PBEF as a marker for the diagnosis and management of patients.

First Report of Leaf and Sheath Spot Caused by Waitea circinata var. zeae on Paspalum vaginatum and Zoysia tenuifolia in China.

Waitea circinata var. zeae was previously reported as the causal agent of leaf and sheath spot on Festuca arundinacea (1) and Panicum tennesseense (2) in the United States. In late May to mid-September 2013, a disease resembling leaf and sheath spot was observed on Paspalum vaginatum in fairways from several golf courses in Hainan Province, China. Affected plants initially had large yellow and brown spots on leaves and sheathes, then the whole plant turned yellowish-brown and eventually died. The same symptoms were also observed on a lawn established with Zoysia tenuifolia in Hainan University. Symptomatic leaves were surface sterilized in 1% hypochlorite for 1 min, rinsed with sterile water three times, and plated onto potato dextrose agar (PDA) amended with 0.01% gentamicin sulfate. Two Rhizoctonia-like fungal isolates were obtained from the diseased P. vaginatum (Isolate no. ML-WC1) and Z. tenuifolia (Isolate no. HNU-1) samples. After incubation on PDA for 1 week at 25°C, white mycelial colonies developed and eventually turned a salmon color with age. Small, white, spherical sclerotia (0.5 to 1 mm in diameter) were observed submerged throughout the agar media after incubation for 1 week and turned a reddish-brown color within 4 weeks. The two isolates were tentatively identified as W. circinata var. zeae based on these characteristics. The internal transcribed spacer (ITS) region of the ribosomal DNA gene was amplified and sequenced using primer pair ITS1/ITS4. The sequences of the two isolates (GenBank Accession Nos. KJ717943 and KJ717944) were more than 99% similar to W. circinata var. zeae (JQ688056 and JQ688059) sequences deposited in GenBank. To confirm pathogenicity, inocula were prepared by incubating autoclaved rye grains with strains ML-WC1 and HNU-1 for 2 weeks at 25°C. Ten colonized rye grains were uniformly spread around the crowns of 6-week-old P. vaginatum and Z. tenuifolia seedlings grown in 10-cm-diameter pots. Each isolate was placed in four separate pots and four control plants were treated with non-inoculated grain. All pots were covered with translucent plastic bags and placed in a greenhouse at 24 ± 2°C with a 12-h light/dark cycle. By 1 week post-inoculation, significant blighting of leaves and sheaths was observed, while non-inoculated plants showed no symptoms. W. circinata var. zeae was successfully re-isolated from symptomatic plants and confirmed by its Rhizoctonia-like mycelium and small, reddish-brown, spherical sclerotia on the PDA. Recently a related species, W. circinata var. circinata, causing brown ring patch on two cool-season grasses was reported in China (3). However, the isolates of W. circinata var. zeae were distinguished from W. circinata var. circinata base on ITS sequence data and morphological characters. To our knowledge, this is the first report of W. circinata var. zeae infecting P. vaginatum and Z. tenuifolia in China. References: (1) S. S. Martin, Jr. and L. T. Lucas. Plant Dis. 67:676, 1983. (2) N. A. Mitkowski. Plant Dis. 87:1006, 2003. (3) X. X. Ni et al. Plant Dis. 96:12, 2012.

A novel 31-bp indel in the paired box 7 (PAX7) gene is associated with chicken performance traits.

1. A novel 31-bp indel polymorphism in intron 3 of the chicken paired box 7 (PAX7) gene was identified and genotyped in an F2 resource population of Gushi chicken crossed with Anka broiler to analyse its associations with chicken growth, carcass and meat quality traits. 2. Results showed that the 31-bp indel was significantly associated with body weight at 4, 6, 8, 10, 12 weeks of age and body size indices including shank length, shank girth, body slanting length at 8 and 12 weeks of age. Significant associations were found for carcass weight, semi-evisceration weight, evisceration weight, breast muscle fibre diameter, leg muscle fibre diameter, breast muscle fibre density, while no significant association with leg muscle fibre density was observed. 3. It was concluded that the 31-bp indel in intron 3 of the PAX7 gene was associated with chicken growth, carcass and meat quality traits where the 31-bp deletion had a negative effect on chicken growth and carcass traits and positive effect on meat quality traits.

[Progress in epidemiological research of norovirus infection].

With characteristics of high infectivity, diverse transmission routes and high variation, norovirus is the main pathogen of sporadic cases and outbreaks of acute gastroenteritis, resulting in a serious disease burden. This paper summarizes the latest progress in epidemiological research of norovirus infection from aspects of disease burden caused by acute gastroenteritis, virus variation and predominant strains, prevention and control measures, and immunization and vaccine development.

[Application of two RT-PCR methods for detection of norovirus in market-sold oysters and norovirus genetic characteristic analysis, a survey conducted in Beijing].

Objective: To evaluate the application of real-time RT-PCR and semi-nested RT-PCR in the detection of norovirus in oysters and analyzing the genetic characteristics of the isolates. Methods: Real-time fluorescent RT-PCR and semi-nested RT-PCR were used to detect norovirus GⅠ/GⅡ in fresh oysters collected from the markets in Beijing from November 2014 to October 2015. The detection rate of the parallel test was also analyzed. In addition, the reliability of semi-nested RT-PCR was evaluated by agreement rate and consistency test (Kappa value). The positive products of norovirus GⅠ/GⅡ capsid protein region gene by semi-nested RT-PCR were sequenced. Software BioEdit 7.0.9.0 was used for sequence alignment, and software Mega 6.0 was used to construct the evolutionary tree. Results: In 72 samples, the detection rate of norovirus was 31.94% (23/72) by real-time RT-PCR, 38.89% (28/72) by semi-nested RT-PCR and 48.61% (35/72) by parallel test. The coincidence rate of the two methods was 73.61%, a moderate degree (Kappa value =0.43). A total of 13 norovirus strains were successfully sequenced, and 11 strains (7 GⅡ.17 strains, 2 GⅡ. 4 Sydney_ 2012 strains, 1 GⅡ. 1 strain and 1 GⅡ. 21 strain) were obtained from norovirus positive samples by two RT-PCR methods, two strains (1 GⅡ. 17 strain and 1 GⅡ. 3 strain) were obtained from real-time RT-PCR negative samples which were positive for norovirus by semi-nested RT-PCR. The similarity between these strains and reference strains from diarrhea patients, environmental sewage, and shellfish products were 84.4% - 100.0%. Conclusions: The parallel test of norovirus in oysters by two RT-PCR methods can improve the detection rate and detect more genotypes. Norovirus strains in oysters were highly homologous with reference strains from diarrheal patients, environmental sewage, and shellfish products. Therefore, surveillance, prevention and control for norovirus should be carried out in people who have frequent contacts with oysters and related environments.

A novel monoclonal antibody against human CD80 and its immune protection in a mouse lupus-like disease.

Blockade of the interactions between CD28/CTLA-4 and their ligands, CD80 (B7, B7.1)/CD86 (B70, B7.2), is an attractive means to induce antigen-specific peripheral tolerance in autoimmune disease and organ transplantation. In this study, we generated and characterized a monoclonal antibody (Clone 4E5) against human CD80. 4E5 could recognize both human and mouse CD80 and suppress mixed lymphocyte reaction in vitro. To investigate their potency for clinical use, we further administrated 4E5 to a mouse lupus-like disease model (C57BL/J6) induced by Pristane. 4E5 could inhibit the immune response and attenuate the severity of lupus-like disease. The data showed 4E5 function and suggested that blockade of CD80/CD28 co-stimulatory signal pathway with 4E5 is a promising strategy to decelerate the progression of lupus-like disease and other autoimmune diseases.

miR-144-3p increases radiosensibility of gastric cancer cells by targeting inhibition of ZEB1.

PURPOSE: This study set out to probe into the effect and mechanism of miR-144-3p on radiosensitivity of gastric cancer (GC) cells. METHODS: Cancer tissue and paracancerous tissue of GC patients admitted to our hospital were collected, their miR-144-3p expression was tested, GC cells were transfected, and survival and biological behavior of those cells under radiation were detected. RESULTS: After detection, miR-144-3p expression was down-regulated in GC tissue, while ZEB1 was up-regulated. There was no remarkable difference in the survival fraction of cells in each group before receiving radiation, but that of tumor cells decreased obviously (p < 0.05) after radiation exposure. Survival fraction of cells overexpressing miR-144-3p or silencing ZEB1 decreased more obviously, while the inhibition of miR-144-3p or overexpressing ZEB1 was weaker. Biological behavior of cells under 6 Gy radiation was detected. It was found that miR-144-3p overexpression or silencing ZEB1 dramatically inhibited the proliferation activity of GC cells under 6 Gy radiation, increased the levels of pro-apoptotic Bax and caspase-3 proteins (p < 0.05) and decreased the anti-apoptotic protein Bcl-2 level (p < 0.05), resulting in an increase in the apoptosis rate of cells. miR-144-3p was confirmed to be ZEB1 targeting site by dual luciferase report. Moreover, rescue experiments prove that it can increase the radiosensitivity of GC cells by regulating ZEB1 expression. CONCLUSION: miR-144-3p expression was down-regulated in GC, and it can increase the radiosensitivity of those cells by inhibiting ZEB1 expression.

[Exploration on contamination and transmission of SARS-CoV-2 in imported cold chain aquatic products].

Contaminations of SARS-CoV-2 have been found for many times in imported cold chain aquatic products and their packaging materials in China. The purpose of this paper is to analyze the contamination status, sources and transmission risks of SARS-CoV-2 in imported cold chain aquatic products, and try to put forward relevant suggestions and strategies in order to provide evidence for the prevention and control of SARS-CoV-2 infection.

[Sampling survey report on Chinese physicians' cognition of the guidelines on diagnosis and treatment of colorectal cancer].

Objective: To investigate and evaluate the mastery and recognition degree of Chinese clinicians on the 2015 edition of the Chinese Criteria for Diagnosis and Treatment of Colorectal Cancer in order to provide useful suggestions for updating and formulating diagnosis and treatment standards. Methods: Simple random sampling was used to conduct a questionnaire survey in 1500 colorectal cancer-related doctors in general hospitals and cancer hospitals from 115 cities in China. The study included the following guidelines: (1) Chinese Criteria for Diagnosis and Treatment of Colorectal Cancer (2015 edition); (2) Chinese Society of Clinical Oncology Colorectal Cancer Guidelines 2017 (CSCO 2017); (3) National Comprehensive Cancer Network (NCCN) Colon Cancer Guidelines 2017.v1; (4) European Society for Medical Oncology (ESMO) Rectal Cancer Guidelines. The survey was carried out in 2017 and 2019 respectively. In the first phase, the questionnaire included 4 dimensions (guideline cognition, detection and diagnosis, pathology and staging, treatment), and 1500 questionnaires were distributed. In the second phase, the questionnaire contained 3 dimensions (basic information, current treatment status of metastatic colorectal cancer, academic expectations), and 350 questionnaires were distributed. Case (%) was used to indicate the categorical variable data, and chi-square test was used for comparison between groups. P<0.05 indicated that the difference was statistically significant. Results: In the first phase, 1472 valid questionnaires were collected, and the questionnaire efficiency was 98.1% (1472/1500). In the second phase, 337 valid questionnaires were collected, and the questionnaire efficiency was 96.3% (337/350). In the survey of the first phase, doctors had some knowledge and compliance with various guidelines, but the most familiar one was the NCCN guidelines, accounting for 90.7% (1335/1472). In the dimension of detection and diagnosis, the overall correct rate was 64.1% (944/1472). The correct rate of doctors in the first-tier cities was 55.6% (148/266), which was lower than 59.1% (182/308) and 72.9% (369/506) in the second- and the third-tier cities, and the difference was statistically significant (χ(2)=42.140, P<0.001). More than 60.0% (883/1472) of doctors was clear about the specification requirements of the staging evaluation and pathological examination. However, in terms of rectal cancer local staging evaluation, the ratio of doctors who would choose rectal MRI in the first-tier cities was lower than that of those in other tier cities [51.5% (137/266) vs. 65.6% (202/308), 63.2% (320/506) and 61.2% (240/392)], and the difference was statistically significant (χ(2)=41.886, P<0.001). In the dimensions of staging evaluation and pathological examination, there were no statistically significant differences in cognition between general and specialist hospitals (P>0.05). In the treatment dimension, 79.8% (1175/1472) of doctors considered the preoperative treatment as a necessary option for patients with middle and low locally advanced (over cT3) rectal cancer. 46.3% (681/1472) of doctors, including 60.3% (433/718) of surgeons, and 31.4% (225/716) of physicians, had a vague idea that irinotecan could not be used for postoperative adjuvant treatment of colorectal cancer. In the survey of the second phase, 93.8% (316/337) of doctors approved potentially curative systemic (conversion) therapy, and 95.3% (321/337) of doctors followed the clinical guidelines in the treatment of metastatic colorectal cancer. Regarding academic expectations, the clinician's concern for surgery was more practical, and 79.2% (267/337) of doctors wanted to know the best options of conversion therapy for potentially curable metastatic colorectal cancer. In contrast, the clinician's concern for internal medicine was more exploratory, and 80.1% (270/337) of doctors focused on selecting targeted drugs and the sequence of treatment. Conclusions: This investigation has a preliminary understanding of the diagnosis and treatment of colorectal cancer in China. (1) There are many guidelines for doctors' reference, but doctors' understanding of domestic guidelines is not as good as NCCN guidelines. (2) The degree of understanding of the guidelines varies significantly among doctors in different cities. (3) The promotion of guidelines should focus on basic concepts and theories. (4) The detection, diagnosis, and treatment of colorectal cancer should be better trained and promoted. (5) The concept of conversion therapy for metastatic colorectal cancer is highly recognized.

[Effects on the integrated treatment of colorectal cancer patients during COVID-19 epidemic in China: a cross-sectional study].

Objective: To understand the treatment status and effects on colorectal cancer (CRC) patients in China during the COVID-19 pandemic, and provide evidence for decision-making for health-care workers. Methods: The method of cross-sectional study was applied. A questionnaire survey of CRC patients in China was carried out. Their basic and treatment information during the COVID-19 were collected and associated effects on treatment, nursing, state of psychology and needs of social support were analyzed. Results: Of the 1147 participants in the study, 635 (55.4%) were male and 512 (44.6%) were female with mean age of (52.8±12.8) years. The treatment or follow up of 896 (78.1%) CRC patients were affected during the COVID-19 outbreak. A total of 253 patients (22.1%) had their treatment regiments changed, of whom 141 (12.3%) had their chemotherapy regiments postponed or changed, and 83 patients (7.2%) had their surgical treatment affected. Among the above 83 patients, 39 patients (3.4%) underwent emergency surgery. A total of 277 patients (24.1%) had their out-of-hospital care needs affected, mainly due to maintenance of PICC (49.5%, 137/277). CRC patients had poorer sleep quality and increased levels of insomnia than before (P<0.001), and were more distressed, anxious, depressed, and angry than they were before. They presented the more requirements of help (P<0.001). In addition, 376 patients (32.8%) had received telemedicine services, but only 36.4% (137/376) of them were satisfied. Conclusions: The COVID-19 epidemic has effect on the integrated treatment of CRC patients include diagnosis, treatment, examination and prognosis. While protecting CRC patients from being infected with SARS-CoV-2, health-care workers should also actively help them to receive timely and correct treatment and pay attention to their nursing, nutritional, psychological and social support needs in the COVID-19 epidemic.

[Progress on genotyping of norovirus].

Norovirus are now recognized as one of the main pathogens causing acute gastroenteritis in both developed and developing countries. However, norovirus are easily mutated and recombined, and have many genotypes. In early studies, norovirus were amplified and identified by amino acid sequence of VP1 region. It was found that norovirus were easily mutated and recombined in or near the overlapping regions of polymerase and capsid. A two regions genotyping method was positively proposed internationally. Depending on the 2 times standard deviation standard method for two regions identification, norovirus polymerase regions can be divided into 10 gene groups and 76 genotypes including 2 tentative gene groups and 16 tentative genotypes. The VP1 region can be divided into 12 gene groups and 53 genotypes including 2 tentative gene groups and 5 tentative genotypes. However, the tentative gene groups and genotypes need to be further identified and reclassified. In this article, characteristics of norovirus sequences, principles of different genotyping methods, methods of sequence amplification, on-line genotyping tools and the latest studies in norovirus genotypes are reviewed and introduced.

[Systematic review on the characteristics of acute gastroenteritis outbreaks caused by sapovirus].

Objective: To understand the epidemiological and etiological characteristics of outbreaks on acute gastroenteritis caused by sapovirus (SaV) worldwide. Methods: Literature about the outbreaks on acute gastroenteritis caused by SaV were retrieved from the databases including WanFang, CNKI, PubMed and Web of Science after evaluation. Time, geography, setting and population distributions of outbreaks, transmission mode, SaV genotype and clinical characteristics of the patients were analyzed. Results: A total of 34 papers about SaV were included, involving 146 outbreaks occurred between October 1976 and April 2016. In these papers, 138 outbreaks were reported on the related months. All these outbreaks occurred in northern hemisphere. SaV outbreaks occurred all year around, but mainly in cold season, the incidence was highest in December (25 outbreaks) and lowest in in August (2 outbreaks). Most outbreaks were reported by Japan, followed by Canada, the United States of America and the Netherlands. There were 141 outbreaks for which the occurring settings were reported, child-care settings were most commonly reported setting (48/141, 34.04%), followed by long-term care facility (41/141, 29.08%) and hospital (16/141, 11.35%). Clinical symptoms of 1 704 cases in 31 outbreaks were reported, with the most common symptom was diarrhea (1 331/1 704, 78.12%), followed by nausea (829/1 198, 69.20%), abdominal pain (840/1 328, 63.25%), vomiting (824/1 704, 48.36%) and fever (529/1 531, 34.53%). Genotypes of SaV were determined for 119 outbreaks. GⅠ(51/119, 42.86%) and GⅣ (45/119, 37.82%) were predominant. The outbreaks of GⅣ SaV increased suddenly in 2007, and the outbreaks of GⅠ SaV mainly occurred in 2008 and during 2011-2013. Conclusions: SaV outbreaks were reported mainly by developed countries, with most outbreaks occurred in cold season, in child-care settings and long term care facility. GⅠ and GⅣ were the most common genotypes of SaV. Prevention and control of SaV outbreak in China seemed relatively weak, and it is necessary to conduct related training and to strengthen the SaV outbreak surveillance in areas where service is in need.

[Clinicopathological characteristics of type 2 diabetes mellitus complicated with colorectal cancer].

Objective: To analyze the clinicopathological features of type 2 diabetes mellitus complicated with colorectal cancer (DCRC). Methods: A case-control study was conducted. Inclusion criteria: (1) hospitalized patients receiving fibrocolonoscopy; (2) adenocarcinoma and mucinous adenocarcinoma diagnosed by pathology; (3) with preoperative cTNM clinical staging; (4) colorectal cancer patients undergoing surgical treatment; (5) with postoperative pTNM staging; (6) no smoking or drinking habits. Exclusion criteria: (1) familial adenomatous polyposis (FAP); (2) Lynch syndrome; (3) carcinoma of anal canal and perianal carcinoma; (4) multiple primary cancer; (5) with serious cardiocerebrovascular diseases or multiple organ failure. Clinicopathlogical data of 32 DCRC patients who were diagnosed and treated in Peking University Shougang Hospital from December 2017 to December 2018 were retrospectively collected and analyzed. Forty nondiabetic colorectal cancer (CRC) patients during the same period were selected as control group according to the sex ratio and the age difference less than 5 years. Student's t test and χ(2) test were used to compare the difference between the two groups in baseline clinicopathological data, clinical test results, tumor markers and infiltration status of T cells in tumor immune microenvironment. Results: Among 32 DCRC patients, 24 were males and 8 were females with a mean age of (63.0±1.7) years; among 40 CRC patients, 30 were males and 10 were females with a mean age of (60.5±1.6) years. The duration of diabetes mellitus in DCRC patients (from the diagnosis of diabetes mellitus to the diagnosis of colorectal cancer) was (9.2±1.3) years. The body mass index (BMI) of DCRC group was significantly higher than that of CRC group [(24.8±0.6) kg/m(2) vs. (23.2±0.4) kg/m(2), t=2.372, P=0.020]. There were no significant differences in other baseline data (sex, age, primary site of tumor, R0 resection rate, pathological stage, pathological type, differentiation degree of tumor, preoperative intestinal obstruction) between the two groups (all P>0.05). Serum triglyceride level in DCRC group was higher than that in CRC group [(2.1±0.2) mmol/L vs. (1.5±0.1) mmol/L, t=3.085, P=0.003], while hemoglobin [(120.3±5.2) g/L vs. (132.7±2.8) g/L, t=-2.224, P=0.029], anti- thrombin III [(94.2±3.7)% vs. (103.5±2.4)%, t=-2.197, P=0.031], and red blood cell count [(4.2±0.1)×10(12)/L vs. (4.5±0.1)×10(12)L, t=-2.055, P=0.044] were all lower than those in CRC group. The preoperative carcinoembryonic antigen (CEA) level in DCRC group was higher than that in CRC group [(50.3±21.8) µg/L vs. (5.6±1.0) µg/L, t=2.339, P=0.022]. There were no significant differences in preoperative levels of other four tumor molecular markers (CA199, CA242, CA724 and CA125) between the two groups (all P>0.05). The expression of Foxp3 [specific markers of CD4+, CD25+ regulatory T cells (Treg)] in DCRC group was higher than that in CRC group [(82.7±6.2) cell/HPF vs. (62.6±4.9) cell/HPF, t=2.586, P=0.012]. There were no significant differences in the infiltration of CD4, CD8, PD-1 and PD-L1 positive cells between two groups (all P>0.05). Conclusions: The average diabetic history of DCRC patients is nearly 10 years. They have higher BMI and serum CEA level, and more Treg cell infiltration in the tumor. Close attention should be paid to these patients in clinical practice.

[Analysis on influencing factors for acute gastroenteritis outbreaks caused by norovirus in Beijing, 2014-2018].

Objective: To analyze the influencing factors of acute gastroenteritis outbreaks caused by norovirus in Beijing from 2014 to 2018. Methods: Data of acute gastroenteritis events caused by norovirus in Beijing from April 2014 to March 2018 were collected. Unconditional logistic regression model was conducted to identify the risk factors of the outbreaks. Results: A total of 765 acute gastroenteritis epidemics caused by norovirus were reported in Beijing, in which 85.88% (657/765) were cluster events and 14.12% (108/765) were outbreaks. Among the outbreaks, 70.37% (76/108) were reported in 2017; 84.26% (91/108) were reported in winter and spring; 88.89% (96/108) were reported in kindergartens, primary or secondary schools; 81.48% (88/108) were through person-to-person transmission; 93.52% (101/108) were caused by norovirus GⅡ infection. The risk of outbreaks in suburban and out suburb area were 1.84 times (95%CI: 1.13-3.02) and 3.78 times (95%CI: 1.62-8.82) as high as that in urban area, respectively. The risks of outbreaks in primary, secondary schools and other institutions were 6.26 times (95%CI: 3.53-11.10), 14.98 times (95%CI: 6.23-36.01) and 8.71 times (95%CI: 3.07-24.71) as high as that in kindergartens, respectively. The risk of outbreak in which patients having lower hospital visiting rate than the median rate of all events was 2.29 times than that in the context of having higher hospital visiting rate (95%CI:1.42-3.68). The risk of foodborne outbreak was 14.55 times as high as that transmitted through person-to-person (95%CI: 3.15-67.07). Conclusion: Measures such as strengthening the prevention and control of norovirus outbreaks in suburbs, primary schools, secondary schools and other institutions, promoting patients to visit the hospital actively, improving the management of foodborne events and kitchen workers should be taken to reduce the incidence of acute gastroenteritis outbreaks caused by norovirus.