Enterococcus faecalis Extracellular Vesicles Promote Apical Periodontitis.

Enterococcus faecalis is an important contributor to the persistence of chronic apical periodontitis. However, the mechanism by which E. faecalis infection in the root canals and dentinal tubules affects periapical tissue remains unclear. Bacterial extracellular vesicles (EVs) act as natural carriers of microbe-associated molecular patterns (MAMPs) and have recently attracted considerable attention. In this study, we investigated the role of EVs derived from E. faecalis in the pathogenesis of apical periodontitis. We observed that E. faecalis EVs can induce inflammatory bone destruction in the periapical areas of mice. Double-labeling immunofluorescence indicated that M1 macrophage infiltration was increased by E. faecalis EVs in apical lesions. Moreover, in vitro experiments demonstrated the internalization of E. faecalis EVs into macrophages. Macrophages tended to polarize toward the M1 profile after treatment with E. faecalis EVs. Pattern recognition receptors (PRRs) can recognize MAMPs of bacterial EVs and, in turn, trigger inflammatory responses. Thus, we performed further mechanistic exploration, which showed that E. faecalis EVs considerably increased the expression of NOD2, a cytoplasmic PRR, and that inhibition of NOD2 markedly reduced macrophage M1 polarization induced by E. faecalis EVs. RIPK2 ubiquitination is a major downstream of NOD2. We also observed increased RIPK2 ubiquitination in macrophages treated with E. faecalis EVs, and E. faecalis EV-induced macrophage M1 polarization was notably alleviated by the RIPK2 ubiquitination inhibitor. Our study revealed the potential for EVs to be considered a virulence factor of E. faecalis and found that E. faecalis EVs can promote macrophage M1 polarization via NOD2/RIPK2 signaling. To our knowledge, this is the first report to investigate apical periodontitis development from the perspective of bacterial vesicles and demonstrate the role and mechanism of E. faecalis EVs in macrophage polarization. This study expands our understanding of the pathogenic mechanism of E. faecalis and provides novel insights into the pathogenesis of apical periodontitis.

[Alteration and significance of serum lipid levels and nutritional status during BCMA-CAR-T-cell therapy in patients with refractory or relapsed multiple myeloma: a retrospective study based on LEGEND-2].

Objective: To explore the dynamic changes in serum lipid levels and nutritional status during BCMA-CAR-T-cell therapy in patients with refractory or relapsed multiple myeloma (R/R MM) based on LEGEND-2. Methods: The data of patients with R/R MM who underwent BCMA-CAR-T therapy at our hospital between March 30, 2016, and February 6, 2018, were retrospectively collected. Serum lipid levels, controlled nutritional status (CONUT) score, and other clinical indicators at different time points before and after CAR-T-cell infusion were compared and analyzed. The best cut-off value was determined by using the receiver operator characteristic (ROC) curve. The patients were divided into high-CONUT score (>6.5 points, malnutrition group) and low-CONUT score groups (≤6.5 points, good nutrition group), comparing the progression-free survival (PFS) and total survival (OS) of the two groups using Kaplan-Meier survival analysis. Results: Before the infusion of CAR-T-cells, excluding triglycerides (TG), patients' serum lipid levels were lower than normal on average. At 8-14 d after CAR-T-cell infusion, serum albumin (ALB), total cholesterol (TC), high-density lipoprotein (HDL), low-density lipoprotein (LDL), and apolipoprotein A1 (Apo A1) levels dropped to the minimum, whereas CONUT scores reached the maximum. In addition to TG, apolipoprotein B (Apo B) levels increased compared with baseline. After CAR-T-cell therapy, the patients' serum lipid levels significantly increased with well-improved nutritional status. Spearman's related analysis showed that TC, HDL, and ApoA1 levels after CAR-T-cell injection were significantly negatively correlated with the grade of cytokine-release syndrome (CRS) (r=-0.548, P=0.003; r=-0.444, P=0.020; r=-0.589, P=0.001). Furthermore, survival analysis indicated that the CONUT score was unrelated to PFS, and the median OS of patients with R/R MM in the high-CONUT score group was shorter than that in the low-CONUT score group (P=0.046) . Conclusions: During CAR-T-cell therapy, hypolipidemia and poor nutritional status were aggravated, which is possibly related to CRS. The patients' serum lipid levels and nutritional status were significantly improved after CAR-T-cell treatment. The CONUT score affected the median OS in patients treated with CAR-T-cells. Therefore, specific screening and intervention for nutritional status in patients receiving CAR-T-cell therapy are required.

[The concept and development direction of elderly oriented food].

Active response to the challenges posed by aging has been established as a national strategy, accompanied by continuous refinement of policies concerning aging work. Decreased digestive system function is commonly present in the natural aging process of older people, which directly affects their food intake, digestion, and absorption, leading to decreased appetite and various forms of malnutrition. It is also a risk factor for age-related diseases such as sarcopenia, osteoporosis, cognitive impairment, and frailty. Nutrition is the foundation for achieving healthy aging. In order to meet the nutritional needs of the elderly population, the Nutrition and Healthy Aging Working Group at the Shanghai Junshi Institute of Life Sciences introduced the concept of "elderly-oriented food" in 2022. In the future, there is an urgent need for comprehensive collaborative efforts to conduct a series of investigations focused on the dietary habits and nutritional requirements of older individuals, in order to evaluate the level of awareness, genuine demands, dietary preferences, and capabilities of selection regarding to the elderly-oriented food. Simultaneously, it is recommended to introduce "Guidelines for the production and application of elderly-oriented food" at the national level to promote the sustainable and orderly development in food industry.

[Comparison of two child growth standards in assessing the nutritional status of children under 6 years of age].

Objective: To compare the application of China growth standard for children under 7 years of age (China standards) and World Health Organization child growth standards (WHO standards) in evaluating the prevalence of malnutrition in children aged 0-<6 years in China. Methods: The research data came from the national special program for science & technology basic resources investigation of China, named "2019-2021 survey and application of China's nutrition and health system for children aged 0-18 years". Multi-stage stratified random sampling was used to recruit 28 districts (regions) in 14 provinces, autonomous regions or municipalities across the country. Children (n=38 848) were physically measured and questionnaires were conducted in the guardians of the children. The indicators of stunting, underweight, wasting, overweight and obesity were evaluated by China standards and WHO standards respectively. Chi-square test was used to comparing the prevalence of each nutritional status between the two standards, as well as the comparison between the two standards by gender and age. Results: Among the 38 848 children, 19 650 were boys (50.6%) and 19 198 were girls (49.4%), 19 480 urban children (50.1%) and 19 368 rural children (49.9%). The stunting, underweight and wasting cases in the study population were 2 090 children (5.4%), 1 354 children (3.5%) and 1 276 children (3.3%) according to the China standards, and 1 474 children (3.8%), 701 children (1.8%) and 824 children (2.1%) according to the WHO standards, respectively; the above rates according to the China standards were slightly higher than those to the WHO standards (χ2=111.59, 213.14, and 99.99, all P<0.001). The overweight and obesity cases in the study population were 2 186 children (5.6%) and 1 153 children (3.0%) according to the China standards, and 2 210 children (5.7%) and 1 186 children (3.1%) according to the WHO standards, with no statistically significant differences (χ2=0.14 and 0.48, P=0.709 and 0.488, respectively). Compared to the results based on WHO standards, the China standards showed a lower prevalence of overweight and obesity in boys (χ2=14.95 and 5.85, P<0.001 and =0.016, respectively), and higher prevalence of overweight in girls (χ2=12.60, P<0.001); but there was no statistically significant differences in girls' obesity prevalence between the two standards (χ2=2.62, P=0.106). Conclusions: In general, the prevalence of malnutrition among children aged 0-<6 years based on China standards is slightly higher than that on WHO standards. To evaluate the nutritional status of children, it is advisable to select appropriate child growth standards based on work requirements, norms or research objectives.

Combining a Frailty Index Based on Laboratory Data and Pneumonia Severity Assessments to Predict In-Hospital Outcomes in Older Adults with Community-Acquired Pneumonia.

OBJECTIVES: Due to the increased morbidity, mortality, and cost of community-acquired pneumonia (CAP) in older people, strategies directed at improving disease evaluation and prevention are imperative. We independently compared the 30-day in-hospital mortality prediction ability of a frailty index based on laboratory data (FI-Lab) with that of the CURB-65 and the Pneumonia Severity Index (PSI) and then proposed combining them to further improve prediction efficiency. DESIGN: Retrospective cohort study. SETTING AND PARTICIPANTS: Patients aged ≥ 65 years (n = 2039) with CAP who were admitted to Jiangsu Provincial People's Hospital of Nanjing Medical University and Jiangsu Provincial Hospital of Chinese Medicine from January 2019 to June 2022. MEASURES: The 29-item FI-Lab, PSI and, CURB-65 were administered at admission. We defined frailty by the cut-off value of the FI-Lab score (> 0.43). Multivariable logistic regression analysis, together with the calculation of the area under the receiver operating characteristic curve (ROC-AUC), was conducted to identify stratified risks and relationships between the three indices and 30-day mortality. Participants were divided into the following three groups based on age: 65-74 years, 75-84 years, and ≥ 85 years. Hazard ratios (HRs) and 95% confidence intervals (CIs) for mortality due to frailty were calculated. RESULTS: A total of 495 participants ranging from 65 to 100 years of age were ultimately included and divided into age groups (65-74 years, n = 190, 38.4%; 75-84 years, n = 183, 37.0%; ≥ 85 years, n = 122, 24.6%). A total of 142 (28.7%) of the 495 patients were defined as having frailty. All three scores tested in this study were significantly associated with 30-day mortality in the total sample. The ORs were as follows: 1.06 (95% CI: 1.03-1.09, P < 0.001) and 2.33 (95% CI: 1.26-4.31, P = 0.007) for the FI-Lab when the score was treated as a continuous and categorical variable, respectively; 1.04 (95% CI: 1.02-1.05, P < 0.001) for the PSI; and 3.70 (95% CI: 2.48-5.50, P < 0.001) for the CURB-65. In the total sample, the ROC-AUCs were 0.783 (95% CI: 0.744-0.819) for the FI-Lab, 0.812 (95% CI: 0.775-0.845) for the PSI, and 0.799 (95% CI: 0.761-0.834) for the CURB-65 (P < 0.001). The ROC-AUC slightly improved when the FI-Lab was added to the PSI (AUC 0.850, 95% CI: 0.809-0.892, P = 0.031) and to the CURB-65 (AUC 0.839, 95% CI: 0.794-0.885, P = 0.002). Older patients with frailty showed a higher risk of in-hospital mortality, with an HR of 2.25 (95% CI: 1.14-3.58, P < 0.001). CONCLUSION AND IMPLICATIONS: The FI-Lab seems to generate simple and readily available data, suggesting that it could be a useful complement to the CURB-65 and the PSI as effective predictors of 30-day mortality due to CAP in older populations.

A critical review on sources and environmental behavior of organophosphorus flame retardants in the soil: Current knowledge and future perspectives.

Organophosphorus flame retardants (OPFRs) have been widely used in industrial and commercial applications. Unfortunately, the chemical constituents of OPFRs, organophosphate esters (OPEs), which have been proven to be carcinogenic and biotoxic, can release into the environment and pose potential risks to human health. This paper reviews the research progress of OPEs in the soil through bibliometric analysis and comprehensively elaborates on their pollution status, potential sources, and environmental behaviors. The OPE pollution is widely distributed in the soil at concentrations ranging from several to tens of thousands of ng/g dw. Some novel OPEs, newly discovered OPEs in the environment in recent years, are also detected. OPE concentrations vary substantially among landuses, and waste processing areas are important point sources of OPE pollution in the soil. Emission source intensity, physicochemical properties of compounds, and soil properties play important roles in the transfer process of OPEs in the soil. Biodegradation, especially microbial degradation, has potential application prospects in the remediation of OPE-contaminated soil. Brevibacillus brevis, Sphingomonas, Sphingopyxis, Rhodococcus, and other microorganisms can degrade some OPEs. This review helps clarify the pollution status of OPEs in the soil and highlights perspectives for future research.

[Clinical application of laparoscopic sentinel lymph node mapping in early staged cervical cancer].

Objective: To investigate the application of sentinel lymph node biopsy (SLNB) in early-staged cervical cancer by laparoscopy. Methods: It was a prospective, single-arm, single-center clinical study. Seventy-eight cases of cervical cancer patients were collected from July 2015 to December 2018 at the Fourth Hospital of Hebei Medical University. All the patients were injected with tracer into the disease-free block of cervical tissue after anesthesia by the same surgeon who learned sentinel lymph node (SLN) mapping technique in Memorial Sloan-Kettering Cancer Center, and underwent SLN mapping followed by complete pelvic lymphadenectomy. Moreover, all the dissected lymph nodes were stained with hematoxylin eosin staining (HE) pathological examination. Besides, the negative SLN on hematoxylin-eosin staining were detected by immunohistochemistry cytokeratin staining micro-metastasis. To analyze the distribution, detection rate, false negative rate the sensitivity and negative predictive value of the SLN in early-staged cervical cancer by laparoscopy, and explore the value of SLN mapping in predicting the lymph nodes metastasis in early-staged cervical cancer. Results: The overall detection rate of SLN in cervical cancer was 99% (77/78), bilateral detection rate was 87% (68/78). The average of 12.4 lymph node (LN) and 3.6 SLN were dissected for each patients each side. SLN of cervical cancer were mainly distributed in the obturator space (61.5%, 343/558), followed by external iliac (23.5%, 131/558), common iliac (7.3%, 41/558), para-uterine (3.8%, 21/558), internal iliac (2.2%, 12/558), para abdominal aorta (1.1%, 6/558), and anterior sacral lymphatic drainage area (0.7%, 4/558). Fourteen cases of LN metastasis were found among all 78 cases. There were a total of 38 positive LN, including 26 SLN metastasis and 12 none sentinel LN metastasis. Through immunohistochemical staining and pathological ultra-staging, 1 SLN was found to be isolated tumor cells (ITC), and 5 SLNs were found to be micro-metastases (MIC), accounting for 23% (6/26) of positive SLN. SLN mapping with pathological ultra-staging improved the prediction of LN metastasis in cervical cancer (2/14). Metastatic SLN mainly distributed in the obturator space (65%, 17/26), peri-uterine region (12%, 3/26), common iliac region (15%, 4/26), and external iliac region (8%, 2/26). The consistency of the diagnosis of lymph node metastasis by SLN biopsy and postoperative retroperitoneal lymph node metastasis showed that the Kappa value was 1.000 (P<0.001), indicated that the metastasis status of SLN and retroperitoneal lymph node were completely consistent. The sensitivity, specificity, accuracy, false-negative rate, and negative predictive value of SLN biopsy in the diagnosis of lymph node metastasis were 100%, 100%, 100%, 0, and 100%, respectively. Conclusions: SLN in early-staged cervical cancer patients were mainly distributed in the obturator and external iliac space, pathalogical ultra-staging of SLN could improve the prediction of LN metastasis. Intraoperative SLN mapping is safe, feasible and could predict the state of retroperitoneal LN metastasis in early-staged cervical cancer. SLNB may replace systemic pelvic lymphadenectomy.

Characterization of biochar-derived organic matter extracted with solvents of differing polarity via ultrahigh-resolution mass spectrometry.

In recent years, biochar, a porous carbon-based material, has gained attention for its application prospects in contaminated soil remediation and soil improvement. Biochar-derived organic matter has a key role in influencing the migration and transformation of soil elements and pollutants. However, existing research concerning the molecular characteristics of biochar-derived organic matter is limited. Here, we used four polar solvents - dichloromethane (CH2Cl2), acetone (CH3COCH3), methanol (CH3OH), and distilled water (H2O) - to extract organic matter from soybean straw biochar and wheat straw biochar by accelerated solvent extraction (ASE). We characterized the extracts using Fourier-transform ion cyclotron resonance mass spectrometry (FT-ICR-MS). We found considerable differences in organic matter according to the extraction solvents; such differences were related to the polarity of the solvent, as well as intermolecular forces between the solvent and organic matter. CH3OH extracted the most biochar-extractable organic matter components because CH3OH can weaken or destroy oxygen bridge bonds in biochar and form hydrogen bonds with small-molecule organic compounds. CH3OH and H2O have strong extraction capacity for compounds containing heteroatoms. CH2Cl2-extractable organic matter is relatively labile and bioavailable, while CH3OH- and H2O-extractable organic matters are relatively stable. In addition, the binding capacity of biochar-derived organic matter for minerals and pollutants differed among fractions, in part because of differences in molecular weight, atomic O/C and H/C ratios, heteroatom distribution, and biomolecular compounds present in biochar-derived organic matter. The findings in this study help to select appropriate extractants to analyze biochar-derived organic matter for various research purposes, and provides a theoretical basis for biochar-based remediation of contaminated soil.

[Efficacy and prognostic analysis of 125I brathytherapy combined with chemotherapy for pediatric parameningeal rhabdomyosarcoma].

Objective: To analyze the efficacy and prognostic factors in children with parameningeal rhabdomyosarcoma (PMRMS) treated by 125I brachytherapy combined with chemotherapy. Methods: A retrospective analysis of the clinical data of 33 pediatric patients treated with 125I brachytherapy combined with chemotherapy in Peking University Stomatological Hospital from July 2013 to October 2018 was carried out to analyze the efficacy and prognostic factors. Results: Among the 33 patients, 19 were males and 14 were females; the median age was 4 years old (1-12 years old). There were 17 cases with embryonic type, 9 cases with alveolar type, and 7 with undifferentiated type; 26 cases with original PMRMS, and 7 cases with recurrent PMRMS. The tumors occurred in subtemporal-mastoid area in 15 patients, while nasopalatine-paranasal area in 6 cases, and parapharyngeal-submandibular area in 12 cases. There were 28 patients in IRS Ⅲ, and 5 patients in IRS Ⅳ. As for the risk level, 28 cases were in the middle-risk group and 5 cases in the high-risk group. The median follow-up time was 52 months. The 1, 3, and 5-year local control rates were 87.9%, 58.6%, and 49.9%, and the 1, 3, and 5-year survival rates were 93.8%, 60.5%, and 47.5%, respectively. The 5-year local control rate and 5-year survival rate of 12 patients with the tumor in the parapharyngeal-submandibular area were 91.7% and 100%, respectively. The 5-year local control rate and 5-year survival rate of the 6 patients with tumor in the nasopalatine-paranasal area were both 83.3%. The 3-year local control rate and 3-year survival rate of the 15 patients with tumor in the subtemporal-mastoid area were 17.5% and 21.4%. The multivariate survival analysis using Cox proportional risk regression model showed that the tumor located in the subtemporal-mastoid area was an independent risk factor affecting the 5-year overall survival rate (HR=38.40, 95%CI: 4.87-302.52, P=0.001). Within 3 months after 125I seed implantation, the incidence of acute radiotherapy adverse reactions in all patients was 84.8% (28/33). Twenty-one patients (63.6%) had a grade 1 acute radiotherapy reaction, and 7 cases (21.2%) had a grade 2 acute radiotherapy reaction. No acute radiotherapy adverse reactions of grade 3 or 4 occurred. Three months after 125I seed implantation, the adverse reactions were significantly alleviated, and no adverse reactions of grade 3 or above such as skin ulcer or salivary gland fibrosis occurred, and no serious cranio-maxillofacial deformities occurred. Conclusions: 125I seed brachytherapy combined with chemotherapy has a definite clinical effect in the treatment of children with parameningeal rhabdomyosarcoma. The prognosis of rhabdomyosarcoma in the parapharyngeal-submandibular area and nasopalatine-paranasal area is better than that in the subtemporal-mastoid area.

Environmentally vulnerable or sensitive groups exhibiting varying concerns toward air pollution can drive government response to improve air quality.

Air pollution seriously threatens human health, and its consequences are particularly prevalent among environmentally vulnerable or sensitive groups. However, whether the concerns among these groups are different and how they affect air pollution governance remain unclear. Here, we extract 3.8 million haze-related posts from China's Sina Weibo and analyze the concerns raised by these groups by constructing an air pollution notability index. The results show that protection is the key theme for women aged 20-35 years, while elderly individuals are easily influenced by haze-related product ads yet lack awareness of scientific-based protection. Concerns shared by young individuals are more effective in pressuring the government in cities that experience higher levels of pollution. Concerns shared by women are more effective in cities that experience lower levels of pollution. This study evidences the influence of the public concerns conveyed via social media on air pollution governance in China.

[Anemia prevalence and its influencing factors among students involved in the Nutrition Improvement Program for Rural Compulsory Education Students in 2019].

Objective: To analyze anemia prevalence and its influencing factors of students involved in the Nutritional Improvement Program for Rural Compulsory Education Students in 2019. Methods: From the 2019 surveillance system of the Nutrition Improvement Program for Rural Compulsory Education Students, 47 297 primary and middle school students aged 6-17 were included in the study. Hemoglobin level was tested according to the criteria of WHO 2011. Anemia prevalence of different genders, ages, and regions was analyzed. Results: The average hemoglobin level was 135.19 g/L, with the prevalence of anemia as 8.7% in the children aged 6-17. The prevalence of anemia was 10.0% in girls, higher than that in boys (7.4%). The prevalence rates in western and central areas were 9.8% and 7.1%, respectively. From northwest, southwest, central and south, east, north to northeast areas of China, the anemia rate appeared gradually decreasing (10.2%, 9.7%, 8.3%, 7.5%, 5.7% and 3.5%). The anemia prevalence rates were 8.0%, 8.3%, and 10.9% in children from the 6-, 11-, and 14-17 years age groups, respectively. Logistic regression models revealed that students from schools not using catering software (OR=1.482, 95%CI:1.296-1.694,P<0.001), schools not serving lunch (OR=1.241, 95%CI:1.103-1.395,P<0.001), and from relatively low-income families (OR=1.297, 95%CI:1.211-1.389, P<0.001) showed as risk factors for anemia. After supplementing students' dietary factors, the results showed that students who ate meat three or more times a week had a lower risk of anemia (OR=0.907, 95%CI:0.832-0.989, P=0.026). Conclusions: The Nutritional Improvement Program for Rural Compulsory Education Students had an essential impact on improving the anemia prevalence of primary and middle school students. Family income, school location, economic factors, school feeding, and students' diet programs all impacted the prevalence of anemia.

[Lifelong nutrition to prevent and control non-communicable chronic diseases].

Non-communicable chronic diseases(NCD)have become the main burden of disease in China, which cause great challenges to public health and social development. Unhealthy diet is one of the main risk factors of the occurrence and development of NCD. Based on the latest international understanding of various forms of malnutrition and National Nutrition Survey and Monitoring in China, this paper describes the change trend of low weight, overweight and obesity in different age groups and highlights two classic cases: the diabetes research of Daqing in China and NCD prevention and control project of the North Carolina Project in Finland. The article concludes that dietary nutrition intervention is a cost-effective and sustainable key measure to prevent and control NCD.

[Exploration of applying machine learning in establishment of vitamin D classifiers among Chinese elderly].

Objective: To establish vitamin D classification models for Chinese elderly using machine learning techniques. Methods: Based on the datasets of 2010-2012 Chinese nutrition and health surveillance, the basic information and physical exercise of the subjects were collected. The dietary intake of the subjects was collected by using 3 days-24 hours dietary review method and food frequency method. The normal and insufficient vitamin D was outcome variables. Several machine learning techniques, such as random forest, kernel support vector machine, extreme gradient boosting, and ensemble learning were used to establish vitamin D classification models. Results: Based on the two groups of dietary survey data obtained by using 3 days-24 hours dietary review method and food frequency method, the accuracy of vitamin D classification models for Chinese older people were 0.71 and 0.62, with F1 about 0.82 and 0.73, respectively. The area under curve was 0.58 and 0.57 after adjusting parameters and applying ensemble learning method. Age, gender, intake of vegetables, aquatic product and grains, daily housework, and exercise were important factors to the classification of vitamin D among Chinese elderly. Conclusion: Machine learning techniques could be used to establish vitamin D classification models for Chinses elderly, of which random forest and ensemble learning could be more suitable for the construction of vitamin D classification models.

[Epidemiological characteristics of three local epidemics of COVID-19 in Guangzhou].

Objective: To understand the epidemiological characteristics of three local COVID-19 epidemics in Guangzhou and provide reference for optimizing strategies and measures of COVID-19 prevention and control. Methods: The data of local COVID-19 cases in Guangzhou reported as of June 18, 2021 were collected from National Notifiable Disease Report System of China. The software Excel 2019 and SPSS 22.0 were applied for data cleaning and statistical analysis. Results: A total of 726 COVID-19 cases were reported in the three local epidemics in Guangzhou. In the epidemic associated with the outbreak of COVID-19 in Hubei province, 366 cases were reported. Most cases were female (51.6%, 189/366), aged 18-65 years (81.4%, 298/366), jobless/unemployed (32.2%, 118/366) and retired persons (20.2%,74/366). The initial symptoms of most cases were fever (71.6%, 250/349) and cough (60.7%, 212/349). In the epidemic associated with the imported COVID-19 cases from Africa, 207 cases were reported. Most cases were aged 18-40 years (72.9%, 151/207), male (69.6%, 144/207), and engaged in commercial services (62.3%,129/207). The initial symptoms of most cases were no obvious discomfort (55.6%, 15/27) and cough (37.0%, 10/27). In the epidemic associated with Delta variant of SARS-CoV-2, 153 cases were reported, in which women accounted for 58.8% (90/153), most cases were over 41 years old (64.7%,99/153), and retired persons accounted for the highest proportion (32.0%,49/153). The initial symptoms of most cases were cough (32.9%, 48/146) and no obvious discomfort (28.1%, 41/146). The household secondary attack rates of the three local epidemics were 11.2%, 5.7% and 11.5%, respectively. The median (P25, P75) of incubation periods were 6.5 (4.0,10.8) d, 4.0 (2.5, 6.0) d and 4.0 (3.0,5.0) d. The serial intervals median (P25, P75) were 4.0 (3.0, 8.0) d, 4.0 (2.5, 6.0) d and 3.0 (2.0,5.0) d. There were significant differences in gender, age, occupation, initial symptoms, household secondary attack rate and incubation period among the three local COVID-19 epidemics (all P<0.05). In the proportion of the case finding way, passive detection in patient treatment were mainly 44.3%(162/366) in the epidemic associated with the outbreak of COVID-19 in Hubei province,but active community case screening [58.5% (121/207) and 27.5% (24/153)] and close contact management in imported case were mostly [33.3% (69/207) and 67.3% (103/153)] in the epidemic associated with the imported COVID-19 cases from Africa and with Delta variant of SARS-CoV-2, respectively. Conclusions: Due to the different sources of infection, strain types and prevention and control strategies, the epidemiological characteristics of the three local COVID-19 epidemics in Guangzhou differed in demographics, clinical symptoms, transmission routes and case finding, which suggested that it is necessary to improve the key population and common symptom monitoring in the routine prevention and control of COVID-19 to prevent the reemerge of the epidemic.

[The epidemic situation and intervention countermeasures of stroke in Japan].

From 1951 to 1980, stroke was the main cause of disability and death among middle-aged and elderly residents in Japan. Its mortality once stood in the first place among all the developed countries, with the mortality of hemorrhagic stroke significantly higher than that of the western countries. In 1965, the mortality of stroke in Japan reached a peak of 175.8 per 100 000. Since then, it began to decline rapidly with a range of 5%-7%, and dropped to 139.5 per 100 000 in 1980, and from the top cause of death to the third place. By 2010, the mortality had dropped to 97.7 per 100 000. The significant decline in stroke morbidity and mortality in Japan is mainly attributed to controlling important risk factors and the public health service system's improvement. Setting up related policies and regulations to ensure comprehensive interventions and using the existing monitoring systems and surveys to assess interventions' effectiveness also contributes. Given the similarities of epidemiological characteristics and risk factors on stroke in Japan and China, strategies and measures adopted in Japan will have certain positive significance for China.

[Clinical features and treatment efficacy of infantile renal tumors: a multicenter retrospective study].

Objective: To further understand the clinical features, treatment efficacy and risk factors for poor prognosis in infantile-onset renal tumors. Methods: Clinical data of 45 cases of infantile-onset renal tumors from June 2011 to November 2019 in Peking University First Hospital, Beijing Children's Hospital, Beijing Tongren Hospital and Beijing Shijitan Hospital were analyzed retrospectively. The clinical features were summarized and the prognoses were evaluated. Multi-disciplinary diagnosis and treatment was used, including surgery, chemotherapy and radiotherapy. Kaplan-Meier analysis was used to calculate the overall survival rate and the event-free survival rate, while the chi-square test was used to analyze the risk factors for poor prognosis. Results: Among 45 patients, 24 were males and 21 females. The age of onset was 7 (ranged 3-11) months, and the length of tumor at initial diagnosis was 9.7 (ranged 4.9-25.0)cm. The International Society of Pediatric Oncology (SIOP) staging: 5 cases (11%) were in stage Ⅰ, 22 cases in stage Ⅱ (49%), 8 cases in stage Ⅲ (18%), 6 cases in stage Ⅳ (13%), and 4 cases in stage Ⅴ (9%). Risk groups included 5 cases (11%) in the low-risk group, 22 cases (49%) in the intermediate-risk group, and 18 cases (40%) in the high-risk group. Forty-four cases (98%) did not receive preoperative biopsy, 26 cases (58%) received preoperative chemotherapy, 39 cases (87%) received postoperative chemotherapy, and 2 cases (4%) received three-dimensional conformal radiotherapy. The 5-year overall survival rate was (83±7)%, and the 5-year event-free survival rate was (76±8)%. Hematuria as the first symptom (3/8 vs. 83% (30/36), χ²=7.005, P=0.024), tumor long diameter≤8 cm (5/11 vs. 85% (28/33), χ²=5.606, P=0.027) and high-risk pathological group (7/18 vs.100% (26/26), χ²=21.928, P<0.01) were risk factors for poor prognosis of children with renal tumors in this group. Conclusion: The prognosis of children with infantile-onset renal tumors is fairly well, nevertheless the prognosis is poor in patients with hematuria as the first symptom and in high-risk pathological group.

[Research methods to influence of nutrition on human immunity].

Objective: To systematically review the advances in population research methods of dietary nutrition and human immunity. Methods: Related studies on the relationship between dietary nutrition and human immunity were searched in PubMed, Web of Science, Wanfang and China National Knowledge Infrastructure (CNKI) databases from the start date to January 10, 2020. A systematic review of the literatures that met the requirements was carried out. Results: Totally 114 articles were included, including 4 Chinese articles and 110 English articles. There were 22 cross-sectional studies, 16 case-control studies, 41 cohort studies and 35 intervention studies, respectively. The research methods showed a trend of diversification over time. In recent years, the derivative types of case-control studies such as nested case-control studies and case cohort studies received attention. Research factors gradually shifted from a single nutrient or dietary ingredient to food and dietary patterns. The protective effect of nutrition on gene damage, the effect on altering gene expression, and the regulatory effect of genetic polymorphism on the sensitivity of nutrients and inflammatory markers became research hotspots. Conclusion: The epidemiologic research methods of dietary nutrition and human immune function are constantly improving and developing, which play an important role in fully demonstrating the relationship between nutrition and human immune function.