ObjectiveTo understand the seropositivity of neutralizing antibodies (NAb) and low-level NAb against SARS-CoV-2 infection in the community residents, and to explore the impact of COVID-19 vaccination and SARS-CoV-2 infection on the levels of NAb in human serum. MethodsOn the ground of surveillance cohort for acute infectious diseases in community populations in Shanghai, a proportional stratified sampling method was used to enroll the subjects at a 20% proportion for each age group (0‒14, 15‒24, 25‒59, and ≥60 years old). Blood samples collection and serum SARS-CoV-2 NAb concentration testing were conducted from March to April 2023. Low-level NAb were defined as below the 25^th percentile of NAb. ResultsA total of 2 230 participants were included, the positive rate of NAb was 97.58%, and the proportion of low-level NAb was 25.02% (558/2 230). Multivariate logistic regression analysis indicated that age, infection history and vaccination status were correlated with low-level NAb (all P<0.05). Individuals aged 60 years and above had the highest risk of low-level NAb. There was a statistically significant interaction between booster vaccination and one single infection (aOR=0.38, 95%CI: 0.19‒0.77). Compared to individuals without vaccination, among individuals infected with SARS-CoV-2 once, both primary immunization (aOR=0.23, 95%CI: 0.16‒0.35) and booster immunization (aOR=0.12, 95%CI: 0.08‒0.17) significantly reduced the risk of low-level NAb; among individuals without infections, only booster immunization (aOR=0.28, 95%CI: 0.14‒0.52) showed a negative correlation with the risk of low-level NAb. ConclusionsThe population aged 60 and above had the highest risk of low-level NAb. Regardless of infection history, a booster immunization could reduce the risk of low-level NAb. It is recommended that eligible individuals , especially the elderly, should get vaccinated in a timely manner to exert the protective role of NAb.

Objective:To analyze the features of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) co-infected with other common respiratory pathogens among coronavirus disease 2019 (COVID-19) patients in Shanghai City, and to provide a reference for scientific prevention and control of COVID-19 and other respiratory infectious diseases.Methods:Descriptive epidemiological approaches were used to analyze the data of COVID-19 reported cases in Shanghai City from January 2020 to February 2021 in the information system of Chinese Disease Prevention and Control. Clinical data of the participants were collected, and their SARS-CoV-2 nucleic acid-positive respiratory specimens were collected at the time of illness onset or admission. Multiplex reverse transcription-polymerase chain reaction (RT-PCR) was performed to detect the 22 respiratory pathogens. Independent-samples t test was used for statistical analysis. Results:Of the 272 patients with COVID-19, 15(5.5%) had co-infection of SARS-CoV-2 with other respiratory pathogens, all of which were double infection. There were three cases infected with enterovirus/rhinovirus, two of each with adenovirus, human metapneumovirus and coronavirus NL63/HKU1, and one of each with coronavirus 229E, influenza A virus H1N1, parainfluenza virus 1 and respiratory syncytial virus B. Two cases infected with Mycoplasma pneumoniae. Among the 272 COVID-19 patients, 212(77.9%) had fever, 117(43.0%) had cough, 46(16.9%) had fatigue, and 35(12.9%) had sore throat. The white blood cell count of co-infection cases was higher than that of non-co-infection cases ((6.8±1.7)×10 9/L vs (5.3±1.6)×10 9/L), and the difference was statistically significant ( t=3.09, P=0.008). Conclusions:There is a certain proportion of co-infection of SARS-CoV-2 with other respiratory pathogens among the COVID-19 cases in Shanghai City, mainly viral pathogens, especially enterovirus/rhinovirus. A rational combination of drugs was recommended to improve the cure rate. Surveillance of acute respiratory infection should be further strengthened as well.

As a powerful attempt by government to promote the construction of the multi-level healthcare security system and social and commercial integration in China, " City-customized Medical Insurance" still has many problems to be solved at the beginning of its development, such as unclear boundary between government and enterprises, limited coverage and strength of security. On the basis of clarifying the current situation of " City-customized Medical Insurance", and combing the management experience of social and commercial integration in Medicare Part C plan of the United States, the authors put forward that China should make full use of the advantages of the combination of promising government and efficient market, guide differentiated product design, and establish market access and evaluation mechanism, so as to promote the effective connection between China′s commercial health insurance and basic healthcare insurance, and further reduce the people′s medical burden.

Enteral nutrition plays an irreplaceable role in the nutritional treatment of critically ill patients. In order to help clinical medical staff to manage the common complications during the implementations of enteral nutrition for critically ill patients, the consensus writing team carried out literature retrieval, literature quality evaluation, evidence synthesis. Several topics such as diarrhea, aspiration, high gastric residual volume, abdominal distension, etc. were assessed by evidence-based methodology and Delphi method. After two rounds of expert investigations, Expert consensus on prevention and management of enteral nutrition therapy complications for critically ill patients in China (2021 edition) developed, and provided guidance for clinical medical staff.

OBJECTIVE： To establish the method for the content determination of astragaloside Ⅳ， emodin and chrysophanol in Jianpi yishen pills （JYP） and to investigate the effects of JYP on calcium， phosphorus metabolism and inflammatory factors in chronic renal failure （CRF） model rats. METHODS： HPLC method was adopted. The determination of astragaloside Ⅳ， emodin and chrysophanol was perform on Agilent Zorbax SB-C18， Agilent TC C18 column， respectively； mobile phase consisted of acetonitrile-water （36 ∶ 64， V/V） and methanol-0.1％ phosphoric acid solution （75 ∶ 25， V/V）； the detectors were evaporative light-scattering detector and diode-array detector （detection wavelength of 254 nm）； the column temperatures were set at 30 ℃and 25 ℃ at the flow rate of 1.0 mL/min； the sample sizes were 20 and 10 μL. SD rats were randomly divided into normal group， model group， Niaoduqing group （1.80 g/kg） and JYP low-dose， medium-dose and high-dose groups （1.71， 3.43， 6.85 g/kg）， with 10 rats in each group. Except for normal group， CRF model of other groups were established by 5/6 nephrectomy in other groups. Four months after modeling， normal group and model group were given constant volume of water intragastrically； admi- nistration groups were given relevant medicine intragastrically， once a day， for consecutive 12 weeks. The levels of serum creatinine （Scr）， urea nitrogen （BUN）， parathyroid hormone （PTH） and inflammatory factors （IL-6， TNF-α） were measured by ELISA. Methyl thymol blue colorimetric method and phosphomolybdic acid method were used to detect the contents of blood calcium and phosphorus. Correlation of inflammatory factors with related calcium and phosphorus metabolism indexes （blood calcium， blood phosphorus， PTH） were investigated with Pearson assay. RESULTS： The linear range of astragaloside Ⅳ， emodin and chrysophanol were 54.537-381.759， 2.960-20.720， 6.318-44.223 μg/mL， respectively. The limits of quantitation were 0.010， 0.288， 0.216 μg/mL； the limits of detection were 0.003， 0.096， 0.072 μg/mL. RSDs of precision， reproducibility and stability tests were all lower than 3.0％. The recoveries were 97.18％-102.33％（RSD＜3％，n＝9）. After modeling （before medication）， serum contents of Scr and BUN in model group and administration group were increased significantly， compared with normal group （P＜0.01）. After medication， above indexes of administration group were decreased significantly， compared with model group and the same group before medication （P＜0.01）. Compared with normal group， the content of blood calcium were decreased significantly， while the contents of IL-6 and TNF-α were increased significantly （P＜0.01）. Compared with model group， the content of blood calcium were increased significantly in JYP medium-dose and high-dose groups， while serum content of PTH in Niaoduqing group， serum contents of PTH and IL-6 in JYP medium-dose and high-dose groups as well as serum content of TNF-α in administration group were decreased significantly （P＜0.05 or P＜0.01）. JYP had no significant effect on blood phosphorus in rats， and there was no correlation of inflammatory factors with related calcium and phosphorus metabolism indexes （P＞0.05）. CONCLUSIONS： The established content determination method is simple， specific and sensitive， and can be used for content determination of astragaloside Ⅳ， emodin and chrysophanol in JYP. JYP can improve renal function of CRF model rats， relieve calcium metabolism disorder and inhibit the expression of inflammatory factors.

OBJECTIVE： To optimize the water extraction technology of Bupi yangshen granules， and to provide basis for the follow-up research and development of it. METHODS： The contents of astragaloside Ⅳ and salvianolic acid B in water extract of Bupi yangshen granules， were determined by HPLC-ELSD and HPLC-DAD. Using the comprehensive score of contents of astragaloside Ⅳ and salvianolic acid B and extract yield as index， weight coefficient of indicators were determined by AHP， CRITIC and AHP-CRITIC mixed weighting method. L9（34） orthogonal test was used to optimize decoction time， water volume and decoction times in water extraction technology of Bupi yangshen granules. Validation test was also performed. RESULTS： The weight coefficient determined by AHP-CRITIC mixed weighting method was the most reasonable. The optimal extraction technology was decocting twice， adding 12-fold water， 1 h each time. The results of 3 times of validation test showed that the average contents of astragaloside Ⅳ and salvianolic acid B were 8.79， 609.50 mg （total amount of 121 g medicinal herbs extracted from whole prescription）， respectively. The average extract yield was 31.24％. Average comprehensive score was 96.59（RSD＝1.01％，n＝3）. CONCLUSIONS： The optimized water extraction technology is reproducible， stable and feasible. It can provide a scientific basis for the follow-up development and industrial production of Bupi yangshen granules.

Objective To explore the changes of serum vascular endothelial growth factor ( VEGF) and endostatin (ES) in patients with polycystic ovary syndrome (PCOS) and their effects on the ovarian stromal blood flow. Methods From January 2015 to January 2017,sixty cases diagnosed with polycystic ovary syndrome in the Eighth Affiliated Hospital of Sun Yat?sen University were selected into the observation group,and other 60 cases of healthy women with normal menstrual cycle in the same period were selected as the control group. Then, the levels of serum VEGF and ES of the two groups were observed, the patients in the early ovarian follicular blood flow changes were monitored by transvaginal color Doppler ultrasound to observe the bilateral ovaries and the hemodynamic indexes. Hemodynamic indexes (pulsatility index and resistance index) were compared,and the effects of serum VEGF and endostatin levels on ovarian interstitial blood flow were analyzed. Results The PI and RI of the observation group were(1. 3±0. 2) and (0. 5±0. 1),the PI and RI of the control group were (2. 4±0. 4)and(1. 0±0. 1),the differences were statistically significant(t=2. 378,2. 578,P=0. 023,0. 014);the levels of VEGF and ES in the observation group were (1083±167)ng/L and (278±23)ng/L,the levels of VEGF and ES in the control group were (625±71) ng/L and (172±21)ng/L,the differences were statistically significant( t=2. 123,2. 892,P=0. 042,0. 008);there was negative correlation among VEGF and PI and RI ( r=-0. 770,-0. 782,P<0. 01);there was negative correlation among ES and PI and RI ( r=-0. 751,-0. 799,P<0. 01);there was positive correlation between VEGF and ES ( r=0. 552,P<0. 01) . Conclusion The serum levels of VEGF and ES are significantly increase in patients with polycystic ovary syndrome, the imbalance between the two expressions may play an important role in the increase of ovarian stromal blood flow.

Objective To investigate the effect of stress-induced hyperglycemia (SHG) on myocardial perfusion and clinical prognosis in elderly patients with acute myocardial infarction (AMI) who underwent primary percutaneous coronary intervention (PCI). Methods In this study, 459 elderly patients with first-time occurrence of acute ST-elevation myocardial infarction (STEMI) who underwent primary PCI within 12 h from January 2012 to January 2015 were enrolled and followed up. All patients were divided into three groups according to serum glucose (SG) on admission: normal group (SG<7.0 mmol/L, 148 patients), SG elevation group (SG 7.0-11.1 mmol/L, 169 patients) and SHG group (SG>11.1 mmol/L, 142 patients). Myocardial perfusion indexes, including ST segment resolution (STR), TIMI myocardial perfusion grade (TMPG), peak value of creatine kinase (CK)-MB, left ventricular ejection (LVEF), and major adverse cardiac events (MACE) of patients in three groups were measured and compared after emergency PCI. Results The blood glucose levels were increased, ST-elevation 2 h after PCI were well declined, the percentages of patients with TMPG 2-3 were decreased and peak values of CK-MB were increased in the three groups (P<0.05). After 12 months of follow-up, Kaplan-Meier survival analysis showed that cumulative non-events survival rates in three groups had significantly different: 89.2% (132/148) vs. 85.8% (145/169) and 76.1% (108/142), P<0.05. Multivariate Cox regression analysis showed that SHG was the independent predictor for the occurrence of MACE in patients undergoing PCI after adjusting for age and gender (P<0.05). Conclusions SHG in elderly patients with STEMI can decrease myocardial perfusion level after primary PCI, which will lead to high incidence of MACE.

Objective Cerebral ischemic tolerance induced by cerebral ischemic preconditioning has become a hotspot in the researches of ischemic cerebrovascular disease, and its specific mechanism remains to be clarified.This study was to explore the brain protection mechanisms of cerebral ischemic preconditioning by observing the expressions of HIF-1αand VEGF in the cortex area sur-rounding the infarct locus in rats with focal cerebral ischemia /reperfusion ( I/R) after cerebral ischemic preconditioning. Methods A total of 130 male SD rats were randomly divided into three groups:sham operation, middle cerebral artery occlusion, and cerebral is-chemic preconditioning, the animals in the latter two groups subjected to 2, 6, 12, 24, 48 and 72 h of I/R.The expressions of HIF-1α and VEGF at different time points were detected by immunohistochemistry and Western blot. Results In the middle cerebral artery occlusion group, the expressions of HIF-1αand VEGF positive cells and proteins increased at 2 h after I/R, reached the peak at 24 h, and then gradually decreased to and at 72 h, but still higher than in the sham operation group (P<0.05).The expressions of HIF-1αand VEGF positive cells were significantly higher in the cerebral ischemic preconditioning than in the middle cerebral artery occlusion group (all P<0.05), so were the expressions of HIF-1αand VEGF positive proteins in the former group than in the latter (all P<0.05).The sham operation group showed only a little in-crease in the expressions of HIF-1αand VEGF positive cells and proteins. Conclusion Cerebral ischemia reperfusion injury induces the expressions of HIF-1αand VEGF, which can be further upregulated by brain ischemic preconditioning.

Objective To observe the changes of ischemic preconditioning on the expression of hypoxia inducible fac?tor (HIF)-1αand vascular endothelial growth factor (VEGF) in ischemia hippocampus CA1 region after focal cerebral isch?emia/reperfusion (I/R) in rats, and the mechanisms of brain protection from brain ischemia preconditioning (BIP) thereof. Methods The male SD rats were randomly divided into three groups:sham operation (SO) group,middle cerebral artery oc?clusion (MCAO) group and brain ischemia preconditioning (BIP) group. The MCAO group and BIP group were further divid?ed into six subgroups according to perfusion time after I/R including 2 h, 6 h, 12 h, 24 h, 48 h and 72 h. The ischemia pre?conditioning model rats were established. Immunohistochemistry and Western blot assay were used to observe the expres?sions of HIF-1αand VEGF in ischemia hippocampal CA1 region. Results Neurological function deficit was not observed in SO group. Compared with MCAO group, there was a lower neurological function deficit score in BIP group. In MCAO group and BIP group, the expressions of HIF-1αand VEGF positive cells and protein increased at 2 h after I/R, then gradu?ally increased from 6 h to12 h and reached the maximum level at 24 h, then gradually decreased. The levels were still higher at 72 h than those of SO group. The number of HIF-1αand VEGF positive cells and protein were significantly increased in MCAO group and BIP group than that of SO group (P<0.05). The number of HIF-1αpositive cells was higher in BIP group than that in MCAO group except 2 h and 6 h reperfusion groups. The expression of VEGF positive cells, HIF-1αand VEGF protein were significantly higher in BIP group than those in MCAO group at different time points (P < 0.05). Conclusion Ischemic preconditioning plays a protective role in brain, which may be related to up-regulation of HIF-1αand VEGF.