【Objective】 To investigate the electronic screen exposure of preschool children in Longhua District of Shenzhen, and to analyze the influencing factors. 【Methods】 A total of 25 266 children in kindergarten in Longhua District of Shenzhen were selected as study subjects. A self-designed questionnaire (completed by their guardians) was used to investigate the use of electronic products in the families of preschoolers in April 2019. 【Results】 A total of 23 407 valid questionnaires were collected in this survey, of which 12 593 (53.80%) were boys and 10 814 (46.20%) were girls; and 17 188(73.43%) children were 5 years old. Among the surveyed children, the rate of excessive exposure to electronic screens (>1h/d) was 37.72%, and 6.40% of preschool children used electronic products for more than 2 hours per day. There were statistically significant differences between the excessive exposure group and the non-excessive exposure group in gender, household registration, parents′ educational level, average monthly household income, whether exclusive electronic products,whether restriction of children′s use of electronic products, whether living with elders, only children or not, and the type of main caregiver (P<0.05). Multivariate binary Logistic regression analysis showed that girls, mothers with college education or above,not living with elders,primary caregivers being parents or nannies/others,and no exclusive electronic products were protective factors for children′s excessive exposure to electronic products(P<0.05).Non-household resident population,not-only child,and non-restriction of children′s use of electronic products were risk factors for children′s excessive exposure to electronic products(P<0.05). 【Conclusions】 The excessive use of electronic products in preschoolers is a common phenomenon in Longhua district, Shenzhen. Therefore, it is necessary to strengthen the intervention on the use time of electronic products in preschoolers, and pay more attention to the influence of family environmental factors.

[摘 要] 目的：探讨肺积方对肺癌细胞迁移、侵袭及在动物模型中肺转移的影响及其可能的机制。方法：利用TNMplot 数据库、TCGA数据库和DAVID数据库，通过网络药理学方法分析补体相关蛋白CFHR5/MBL2/C9在肺转移瘤组织中的表达及其与免疫细胞浸润的关系，以及相关的生物过程和信号通路。建立2LL细胞小鼠皮下移植瘤模型，用2 g/mL肺积方汤液灌胃给药，每次0.2 mL，连续干预21 d，观察肺积方对模型小鼠肺转移发生率、肺转移灶数目及肺组织CFHR5/MBL2/C9蛋白表达的影响。外泌体示踪实验观察CTC-TJH-01和H1299细胞分泌和吞噬外泌体的能力。采用不同质量浓度的肺积方冻干粉溶液处理H1299和CTC-TJH-01细胞，采用CCK-8、划痕愈合实验、Transwell实验和WB法检测肺积方对肺癌细胞活力、侵袭、迁移和CFHR5/MBL2/C9蛋白表达的影响。结果：网络药理学分析结果提示，CFHR5/MBL2/C9蛋白在肺转移组织中呈高表达（P < 0.05）且与调控免疫应答中的补体系统密切相关。与对照组相比，肺积方组模型小鼠的肺转移灶数量显著减少（P < 0.05）。0~200 μg/mL 肺积方对H1299和CTC-TJH-01细胞的活力均无显著影响（均P > 0.05）。CTC-TJH-01和H1299细胞均可分泌并吞噬对方的外泌体。与0 μg/mL肺积方对照组相比，50~200 μg/mL肺积方组H1299和CTC-TJH-01细胞的迁移和侵袭能力均显著下降（P < 0.05或P < 0.01），细胞中的CFHR5和MBL2蛋白表达水平均显著降低（P < 0.05或P < 0.01），其中CTC-TJH-01细胞在200 μg/mL肺积方溶液处理后C9蛋白表达水平升高（P < 0.05）。结论：肺积方能够通过调控补体相关蛋白CFHR5/MBL2/C9抑制肺癌细胞的迁移和侵袭及模型小鼠的肺转移，这可能与外泌体介导的细胞间通信有关。

Objective: To develop asolvent extraction-direct mercury analyzer method for determination of methylmercury in urine. Methods: After the urinehydrolyzesd by hydrobromic acid, methylmercury was extracted by tolueneand reverse-extracted from L-cysteine solution, it was then detectedbydirect mercuryanalyzer. Results: The linear range was 0.2-50.0 μg/L, and the related coefficient was 0.9999. The relative standard deviations (RSD) within the group were 5.04%-6.64%, and the RSD between the group were 5.65%-8.11 %. The average recovery efficiencies were 85.4%-95.5%. The detection limitation was 0.0482 μg/L and the quantification concentrations was 0.1607 μg/L. Conclusion: The method, which has low detection limit, high sensitivity, easy to operate, is stability for the determination of methylmercury in urine.
Mercury ; Methylmercury Compounds

[摘 要] 目的：基于小鼠渐进衰老模型探讨衰老所致“正虚”的免疫功能衰退表征的特点。方法：使用不同月龄（2、6、15月龄）C57BL/6小鼠，通过流式细胞术检测并比较小鼠外周血和脾组织中T细胞、髓源性抑制细胞（MDSC）及其亚群的丰度变化。结果：外周血中T细胞亚群表型为CD3+CD4+CD44-CD62L+的幼稚CD4+ T细胞（2 vs 6月龄，P=0.137；2 vs 15月龄，P=0.004；6 vs 15月龄，P=0.105）和表型为CD3+CD8+CD44-CD62L+的幼稚CD8+ T细胞（2 vs 6月龄，P=0.179；2 vs 15月龄，P=0.001；6 vs 15月龄，P=0.015）出现与衰老有关的细胞比例降低，差异具有统计学意义。表型为CD3+CD4+CD44+CD62L+的中央记忆CD8+ T细胞出现与衰老有关的比例升高，差异具有统计学意义（2 vs 6月龄，P=0.01；2 vs 15月龄，P=0.007；6 vs 15月龄，P=0.164）。对脾组织的检测结果具有与外周血相同特点。同时，CD8+ T细胞比例随衰老逐渐升高（2 vs 6月龄，P=0.027；2 vs 15月龄，P<0.001；6 vs 15月龄，P<0.001）；表型为CD8+CD28+的活化CD8+ T细胞亚群比例也出现随月龄增长的上升（2 vs 6月龄，P=0.863； 2 vs 15月龄，P=0.016；6 vs 15月龄，P=0.024），差异均具有统计学意义。结论：衰老所致“正虚”过程中，不同免疫细胞亚群变化并不都反映免疫抑制特点，虽然总体免疫功能下降，但单一表型难以反应整体免疫功能变化。

Objective To explore the effect of immune senescence on lung cancer metastasis and reveal the mechanism of Fuzheng traditional Chinese medicine Jinfukang in the prevention and treatment of the metastasis. Methods A lung metastasis model of Lewis lung cancer cells was established in C57BL/6 mice with different ages (15 months, 6 months, and 2 months). Mice in the 6-month-old group were given Jinfukang intragastrically for 42 days. Pulmonary metastasis was analyzed by in vivo imaging, anatomical microscopic observation, and HE staining. The proportion of memory T cells and NK cells in peripheral blood was detected by flow cytometry. Results The lung metastatic tumor formation rate of 15-month-old and 6-month-old mice was significantly higher than that of 2-month-old mice (all P < 0.05). Abundance of CD4+T cells in peripheral blood was positively correlated with age (2-month-old vs. 6-month-old, P=0.041; 2-month-old vs.15-month-old, P=0.041; 6-month-old vs.15-month-old, P=0.953). The abundance of NK cells was negatively correlated with age (2-month-old vs. 6-month-old, P=0.009; 2-month-old vs.15-month-old, P=0.009; 6-month-old vs. 15-month-old, P=0.574). However, the survival time of mice in the Jinfukang group was longer (P > 0.05) and the level of NK cells in peripheral blood was significantly higher (P=0.029) than those in the normal saline group. Conclusion Immune senescence can promote the metastasis of lung cancer. The prolongation of the survival time of mice administered with Jinfukang may be related to delaying immune senescence and increasing the number of NK cells.

BACKGROUND: Shenyankangfu Tablet (SYKFT) is a Chinese patent medicine that has been used widely to decrease proteinuria and the progression of chronic kidney disease. OBJECTIVE: This trial compared the efficacy and safety of SYKFT, for the control of proteinuria in primary glomerulonephritis patients, against the standard drug, losartan potassium. DESIGN, SETTING, PARTICIPANTS AND INTERVENTION: This was a multicenter, double-blind, randomized, controlled clinical trial. Primary glomerulonephritis patients, aged 18-70 years, with blood pressure ≤ 140/90 mmHg, estimated glomerular filtration rate (eGFR) ≥ 45 mL/min per 1.73 m MAIN OUTCOME MEASURES: The primary outcome was change in the 24-hour proteinuria level, after 48 weeks of treatment. RESULTS: A total of 735 participants were enrolled. The percent decline of urine protein quantification in the SYKFT group after 48 weeks was 8.78% ± 2.56% (P = 0.006) more than that in the losartan 50 mg group, which was 0.51% ± 2.54% (P = 1.000) less than that in the losartan 100 mg group. Compared with the losartan potassium 50 mg group, the SYKFT plus losartan potassium 50 mg group had a 13.39% ± 2.49% (P < 0.001) greater reduction in urine protein level. Compared with the losartan potassium 100 mg group, the SYKFT plus losartan potassium 100 mg group had a 9.77% ± 2.52% (P = 0.001) greater reduction in urine protein. With a superiority threshold of 15%, neither was statistically significant. eGFR, serum creatinine and serum albumin from the baseline did not change statistically significant. The average change in TCM syndrome score between the patients who took SYKFT (-3.00 [-6.00, -2.00]) and who did not take SYKFT (-2.00 [-5.00, 0]) was statistically significant (P = 0.003). No obvious adverse reactions were observed in any group. CONCLUSION: SYKFT decreased the proteinuria and improved the TCM syndrome scores of primary glomerulonephritis patients, with no change in the rate of decrease in the eGFR. SYKFT plus losartan potassium therapy decreased proteinuria more than losartan potassium therapy alone. TRIAL REGISTRATION NUMBER NCT02063100 on ClinicalTrials.gov.

Objective　We established a model by using microfluidic chip that is a horizontal side by side diffusion system through microporous separating three adjacent channels in a triple-culture using neurons,astrocytes,and bEnd.3.Methods　(1)In the in vitro microphysiological system of neurovascular unit,we identified the seed density,seed time,seed sequence and seed method.(2)We adopt the repeated measures data of ANOVA to see whether there is significant difference in the viability when the three cell types are tri-cultured and separately mono-cultured.Results　(1) In the novel in vitro NVU model,the seed density of the neurons,astrocytes and bEnd.3 is 5×10^6~10×10^6 /ml,3×10^5~8×10^5个/ml and 1×10^5~5×10^5/ml.The seed sequence is from neurons to astrocytes to bEnd.3.The seed time is that after the previous seeded cells enter the exponential phase,the next cells will be seeded.(2)We adopt the repeated measures data of ANOVA to see whether there is significant difference in the viability when the three cell types are tri-cultured and separately mono-cultured.Conclusion　In this study,neurons,astrocytes and bEnd.3 were tri-cultured by using microfluidic chip.In this tri-culture model,these three kinds of cells have high cell viability.

Objective: To analyze the epidemiological and etiological characteristics of aggregation epidemics of infectious diarrhea induced by norovirus, and to provide the scientific basis for the prevention and control. Methods: A descriptive epidemiological analysis of aggregation epidemics events occurred during 2016-2018 in Longhua District of Shenzhen was carried out, with subtypes identified by real-time fluorescence quantitative PCR, Region B and Region C fragment sequence determination. Results: There were 34 aggregation epidemic events,including 448 cases, the mean attack rate was 18.26%(448/2 454). The median duration of aggregation epidemic was 3 days. The peak season appeared in autumn and winter, and the peak of epidemic emerged from December 2016 to April 2017. About 91.18% (31/34) of the epidemics occurred in schools and child care centers, and among children aged 3-6 years (78.79%, 353/448). The clinical symptoms were mainly nausea and vomiting (95.77%, 408/426) in children and adolescents but diarrhea in adult group (95.45%, 21/22). The differences between vomiting and diarrhea were both statistically significant in the two age groups (χ2=98.89，99.61，P<0.01). 29 cases were transmitted through interpersonal network, of which 21 cases were found to have unregulated treatment of vomit on campus. The detection rate of biological samples was 49.15% (203/413), all of which were G Ⅱ norovirus. The genotype was mainly GⅡ.P16-G Ⅱ.2(n=49)from November 2016 to April 2017. Conclusion Norovirus can cause large-scale outbreaks in child care centers and schools easily. Early standardized patient isolation and proper management of vomit and diarrhea are the key steps in prevention and control measures.

Objective: To observe the disease type and the changes of symptom load during treatment of patients with Ph chromosome/BCR-ABL fusion gene negative myeloproliferative neoplasm (MPN). Methods: A total of 84 patients with MPN diagnosed from May 2017 to January 2019 in People′s Hospital of Longhua District of Shenzhen were selected, and were divided into polycythemia vera (PV) group, essential thrombocyhemia (ET) group, and myelofibrosis (PMF) group according to their subtypes, with 28 cases in each group. The scores of MPN-SAF-TSS were compared among the three groups. Besides, the scores of the scale (myeloproliferative neoplasm symptom assessment form total symptom score, MPN-SAF-TSS) in different treatment periods (at the time of the visit, when the disease progressed, when the disease was stable, when the clinical improvement was made, when the partial remission was completed, at the time of remission and recurrence) were also compared. Results: At the time of initial diagnosis, there were significant differences in the incidences of symptom burdens among the three groups of MPN patients with abdominal fullness (χ²=6.095, P=0.047), abdominal discomfort (χ²=7.342, P=0.025), poor mobility (χ²=13.029, P=0.001), inattention (χ²=6.099, P=0.047), pruritus (χ²=6.956, P=0.031), bone pain (χ²=7.807, P=0.020), fever (χ²=8.000, P=0.018) and weight loss (χ²=27.340, P<0.001). The incidences of poor mobility (85.71%, 24/28), inattention (67.86%, 19/28) and weight loss (82.14%, 23/28) in PMF group were significantly higher than those in PV group [42.86% (12/28), 39.29% (11/28), 35.71% (10/28)] and ET group [46.43% (13/28), 39.29% (11/28), 14.29% (4/28)] (all P<0.05). The incidences of abdominal discomfort (75.00%, 21/28) and bone pain (60.71%, 17/28) in PMF group were higher than those in PV group [39.29% (11/28), 25.00% (7/28)] (both P<0.05). The incidences of abdominal fullness (89.29%, 25/28) and fever (42.86%, 12/28) in PMF group were higher than those in ET group [60.71% (17/28), 10.71% (3/28)] (both P<0.05). The incidence of pruritus in PV group (71.43%, 20/28) was higher than that in ET group (42.86%, 12/28) and PMF group (39.29%, 11/28) (both P<0.05). Symptom load scores of patients with fatigue (χ²=368.594, P<0.001), abdominal fullness (χ²=261.312, P<0.001), abdominal discomfort (χ²=195.629, P<0.001), poor mobility (χ²=217.862, P<0.001), lack of concentration (χ²=280.664, P<0.001), night sweats (χ²=239.650, P<0.001), pruritus (χ²=254.418, P<0.001), bone pain (χ²=180.291, P<0.001), fever (χ²=231.613, P<0.001) and weight loss (χ²=227.831, P<0.001) were significantly different during different therapeutic periods. The fatigue symptom load score was higher when the disease progressed than that at the time of the visit (P<0.05), and the symptom score of abdominal fullness was lower than that at the time of visit (P<0.05). Symptom load scores of weakness and pruritus when the condition was stable was lower than those when the disease progressed (both P<0.05). When the clinical improvement was made, symptom load scores of weakness, abdominal discomfort, inattention, night sweats, weight loss were lower than those when the disease was stable (all P<0.05). Symptom load scores of abdominal fullness, poor mobility, inattention, night sweats and pruritus in partial remission period decreased compared to temporary improvement period (all P<0.05). Compared to the partial remission period, the symptom load scores of weakness, abdominal fullness, night sweats, pruritus, bone pain and weight loss in complete remission period were lower (all P<0.05). At last, symptom load scores of weakness, abdominal fullness, abdominal discomfort, poor mobility, inattention, night sweats, pruritus, bone pain, fever and weight loss in recurrence period were higher than those in complete remission period (all P<0.05). Conclusion There are several differences in the main clinical symptoms among patients with different MPN subtypes, and there are significant changes in the main clinical symptoms as the disease progresses or turns around.

OBJECTIVEEscape from the body's immune response is a basic characteristic of lung cancer, and indoleamine-2,3-dioxygenase (IDO) plays a key role in mediating immune escape of non-small-cell lung cancer, which leads to recurrence and metastasis. Feiji Recipe, a compound Chinese herbal medicine, has the effect of stabilizing lesions and prolonging survival in patients with lung cancer. The purpose of this study was to investigate the mechanisms underlying the anticancer properties of Feiji Recipe.

METHODSAn orthotopic transplant model of mouse Lewis lung cancer, with stable expression of IDO gene, was established in C57BL/6 mice. Optical imaging was used to observe the effects of Feiji Recipe in the treatment of lung cancer in vivo. The effects of Feiji Recipe on the proliferation of mouse Lewis lung cancer cell line 2LL, 2LL-enhanced green fluorescent protein (2LL-EGFP) and 2LL-EGFP-IDO were investigated, and the apoptosis of T-cells was examined by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide using flow cytometry. Chemical composition of Feiji Recipe was validated by high-performance liquid chromatography.

RESULTSCompared to the control group, the survival of animals treated with Feiji Recipe was significantly prolonged (P = 0.0074), and the IDO protein level decreased (P = 0.0072); moreover, the percentages of CD4CD25 T-cells and Foxp3 T-cells were significantly decreased (P < 0.05). The molecular mechanism of Feiji Recipe against lung cancer may relate to the regulation of immune cells, such as T-cells and regulatory T-cells.

CONCLUSIONThe molecular mechanism of Feiji Recipe in treatment of lung cancer is to restore the function of T-cells in the cancer microenvironment through interfering with the IDO pathway.

Animals ; Apoptosis ; drug effects ; Carcinoma, Lewis Lung ; drug therapy ; enzymology ; immunology ; physiopathology ; Cell Proliferation ; drug effects ; Disease Models, Animal ; Drugs, Chinese Herbal ; administration & dosage ; Growth Inhibitors ; administration & dosage ; Humans ; Indoleamine-Pyrrole 2,3,-Dioxygenase ; genetics ; immunology ; Lung Neoplasms ; drug therapy ; enzymology ; immunology ; physiopathology ; Male ; Mice ; Mice, Inbred C57BL ; T-Lymphocytes, Regulatory ; drug effects ; immunology