ObjectiveTo describe the epidemic characteristics of COVID-19 after policy adjustment from “Category B notifiable disease with category A management” to “Category B notifiable disease with category B management”， and to explore the protective effect of previous infection with SARS-CoV-2 on common symptoms of reinfection. MethodsHealthcare workers infected with SARS-CoV-2 in a grade A tertiary hospital in Shanghai were included in the study from December 4， 2022 to January 11， 2023. Data on demographic characteristics， clinical symptoms， medical history， and COVID-19 vaccination history were collected. We determined the epidemiological curve and characteristics， and then compared the difference in the severity of clinical symptoms between primary and reinfection subjects. ResultsA total of 2 704 cases were included in the study， of which 45 had reinfection， 605 （22.4%）were males， 608 （22.5%）were doctors， 1 275 （47.2%） were nurses， and 2 351 （86.9%） received ≥3 doses of COVID-19 vaccination. The average age of these healthcare workers was （34.9±9.1） years old. The number of cases with mild/moderate illness， asymptomatic infection， fever， headache， dry cough， expectoration， and chest tightness were 2 704 （100.0%）， 92 （3.4%）， 2 385 （88.2%）， 2 066 （76.4%）， 1 642 （60.7%）， 1 807 （66.8%）， and 439 （16.2%）， respectively. Reinfection was a protective factor for fever （OR=0.161， P<0.001）， headache （OR=0.320， P<0.001）， and peak body temperature （β=-0.446， P<0.001）. ConclusionFollowing the COVID-19 policy adjustment as a category B notifiable disease， healthcare workers at a grade A tertiary hospital in Shanghai predominantly experiences mild to moderate COVID-19 symptoms. Reinfection results in milder clinical manifestations， with a lower proportion of being asymptomatic.

Objective:To observe the effect of high expression of polypyrimidine tract-binding protein-associated splicing factor (PSF) on low concentration of 4-hydroxynonenal (4-HNE) induced human retinal microvascular endothelial cells (HRMECs), and explore the possible mechanism.Methods:The HRMECs cultured in vitro were divided into 4-HNE treated group, PSF overexpression group combined with 4-HNE group (PSF+4-HNE group), PSF overexpression+ML385 treatment combined with 4-HNE group (PSF+ML385+4-HNE group), and 4-HNE induced PSF overexpression group with LY294002 pretreatment (LY294002+4-HNE+PSF group). Cell culture medium containing 10 μmmol/L 4-HNE was added into 4-HNE treatment group, PSF+4-HNE group, PSF+ML385+4-HNE group for 12 hours to stimulate oxidative stress. 1.0 μg of pcDNA-PSF eukaryotic expression plasmid were transfected into PSF+4-HNE group and PSF+ML385+4-HNE group to achieve the overexpression of PSF. Also cells were pretreated with ML385 (5 μmol/L) for 48 hours in the PSF+ML385+4-HNE group, meanwhile within the LY294002+4-HNE+PSF group, after pretreatment with LY294002, cells were treated with plasmid transfection and 4-HNE induction. Transwell detects the migration ability of PSF to HRMECs. The effect of PSF on the lumen formation of HRMECs was detected by using Matrigel in vitro three-dimensional molding method. Flow cytometer was used to detect the effect of PSF overexpression on reactive oxygen (ROS) level in HRMECs. Protein immunoblotting was used to detect the relative expression of PSF, nuclear factor E2 related factor 2 (Nrf2), heme oxygenase-1 (HO-1) protein, and phosphoserine threonine protein kinase (pAkt) protein. The comparison between the two groups was performed using a t-test. Results:The number of live cells, migrating cells, and intact lumen formation in the 4-HNE treatment group and the PSF+4-HNE group were 1.70±0.06, 0.80±0.13, 24.00±0.58, 10.00±0.67, and 725.00±5.77, 318.7±12.13, respectively. There were significant differences in the number of live cells, migrating cells, and intact lumen formation between the two groups ( t=12.311, 15.643, 17.346; P<0.001). The results of flow cytometry showed that the ROS levels in the 4-HNE treatment group, PSF+4-HNE group, and PSF+ML385+4-HNE group were 816.70±16.67, 416.70±15.44, and 783.30±17.41, respectively. There were statistically significant differences between the two groups ( t=16.311, 14.833, 18.442; P<0.001). Western blot analysis showed that the relative expression levels of pAkt, Nrf2, and HO-1 proteins in HRMECs in the 4-HNE treatment group, PSF+4-HNE group and LY294002+4-HNE+PSF group were 0.08±0.01, 0.57±0.04, 0.35±0.09, 0.17±0.03, 1.10±0.06, 0.08±0.11 and 0.80±0.14, 2.50±0.07, 0.50±0.05, respectively. Compared with the PSF+4-HNE group, the relative expression of pAkt, Nrf2, and HO-1 proteins in the LY294002+4-HNE+PSF group decreased significantly, with significant differences ( t=17.342, 16.813, 18.794; P<0.001). Conclusion:PSF upregulates the expression of HO-1 by activating the phosphatidylinositol 3 kinase/Akt pathway and inhibits cell proliferation, migration, and lumen formation induced by low concentrations of 4-HNE.

Objective:To investigate the effect of Nodal protein on retinal neovascularization under hypoxia.Methods:In vivo animal experiment: 48 healthy C57BL/6J mice were randomly divided into normal group, oxygen-induced retinopathy (OIR) group, OIR+dimethyl sulfoxide (DMSO) group and OIR+SB431542 group, with 12 mice in each group. Retinal neovascularization was observed in mice at 17 days of age by retina flat mount. Counts exceeded the number of vascular endothelial nuclei in the retinal inner boundary membrane (ILM) by hematoxylin eosin staining. In vivo cell experiment: human retinal microvascular endothelial cells(hRMEC) were divided into normal group, hypoxia group, hypoxia+DMSO group and hypoxia +SB431542 group. The cell proliferation was detected by thiazolyl blue colorimetry (MTT). The effect of SB431542 on hRMEC lumen formation was detected by Matrigel three-dimensional in vitro molding method. Cell migration in hRMEC was detected by cell scratch assay. The Seahorse XFe96 Cell Energy Metabolism analyzer measured extracellular acidification rate (ECAR) of intracellular glycolysis, glycolysis reserve, and glycolysis capacity. One-way analysis of variance was used to compare groups.Results:In vivo animal experiment: compared with normal group, the neovascularization increased in OIR group ( t=41.621, P<0.001). Compared with OIR group, the number of vascular endothelial nuclei breaking through ILM in OIR+SB431542 group was significantly reduced, and the difference was statistically significant ( F=36.183, P<0.001). MTT test results showed that compared with normal group and hypoxia+SB431542 group, the cell proliferation of hypoxia group and hypoxia+DMSO group was significantly increased, and the difference was statistically significant ( F=39.316, P<0.01). The cell proliferation of hypoxia+SB431542 group was significantly lower than that of hypoxia+DMSO group, and the difference was statistically significant ( t=26.182, P<0.001). The number of intact lumen formation and migration cells in normal group, hypoxia group, hypoxia+DMSO group and hypoxia+SB431542 group were statistically significant ( F=34.513, 41.862; P<0.001, <0.01). Compared with the hypoxia+DMSO group, the number of intact lumen formation and migrating cells in the hypoxia+SB431542 group decreased significantly, and the differences were statistically significant ( t=44.723, 31.178; P<0.001,<0.01). The results of cell energy metabolism showed that compared with the hypoxia +DMSO group, the ECAR of intracellular glycolysis and glycolysis reserve in the hypoxia +SB431542 group was decreased, and the ECAR of glycolysis capacity was increased, with statistical significance ( t=26.175, 33.623, 37.276; P<0.05). Conclusion:SB431542 can inhibit the proliferation, migration and the ability to form lumens, reduce the level of glycolysis of hRMECs cells induced by hypoxia.

Background: Crawling-type gastric adenocarcinoma is a rare subtype of gastric cancer, however, the understanding on this special entity of gastric cancer is still lacking. Aims: To investigate the clinical, endoscopic and pathological characteristics of crawling-type early gastric adenocarcinoma. Methods: Patients diagnosed as crawling-type early gastric adenocarcinoma in Songjiang Hospital Affiliated to Shanghai Jiao Tong University School of Medicine from January 2016 to December 2021 were recruited consecutively in a retrospective study. The clinical data were reviewed, the pathological specimens were collected for immunohistochemical staining, and a telephone follow-up was conducted for prognosis analysis. Results: Fourteen patients with crawling-type early gastric adenocarcinoma and fulfilling the inclusion criteria were enrolled in the study, of them, 9 were male, 5 were female, and the mean age was 65.9 years old. No family history of gastric cancer was reported. The clinical manifestations were not specific. All patients were positive for Helicobacter pylori (Hp) infection. Tumors were more likely to occur in the middle and lower thirds of the stomach, with marked atrophic background mucosa. Macroscopically, 11 lesions were superficial-depressed (0-IIc) and 3 were superficial-flat type (0-IIb+ IIc). The color of the lesions was red. Lesions with indistinct border were observed endoscopically in 10 cases. Complete resection was achieved in all 14 patients after endoscopic submucosal dissection n=10 or surgical treatment n=4. Three submucosal and 11 intramucosal infiltration were observed pathologically. Immunohistochemical results of gastric (MUC5AC and MUC6) and intestinal (MUC2, CD10 and CDX-2) markers showed that most of the patients were mixed immunophenotype; the Ki-67 index ranged mostly between 30% and 70%. In a mean follow-up time of 38 months, all 14 patients were survived. Two patients with heterochronous early gastric cancer were found by follow-up endoscopy. Conclusions: When a superficial-depressed or superficial-flat type tumor with reddish color change and atrophic background mucosa is observed endoscopically in an Hp-positive patient, the possibility of crawling-type early gastric adenocarcinoma should be considered. Adequate preoperative evaluation should be carried out to judge the extent and depth of tumor invasion, which may guide the decision of treatment strategy. Postoperative endoscopic surveillance is recommended.

Objective:To observe the expression of miRNA in retinal tissue of mice with oxygen-induced retinopathy (OIR), and screen miRNAs related to p21 and retinal neovascularization (RNV) formation.Methods:A experimental study. Forty healthy 7-day-old C57BL/6J mice were randomly divided into normal group and OIR group, with 20 mice in each group. The oxygen induced RNV model was constructed in the OIR group, and no treatment was performed in the normal group. At the age of 17 days, the mice were killed and the RNV of mice was observed by retinal fluorescence; the nuclei of vascular endothelium that broke through the inner limiting membrane of retina were counted under light microscope. The retinal tissues were taken for miRNA chip analysis to detect the differentially expressed miRNAs between the normal group and the OIR group. The resulting differential miRNA target genes were subjected to enrichment analysis based on gene annotation (GO) and Kyoto Encyclopedia of genes and genomes (KEGG); miRNAs and pathways that may be related to p21 were screened through Targetscan, MiRanda and MicroT-CDs database alignment. Independent sample t-test was used for pairwise comparison between groups. Results:Compared with the normal group, the area of nonperfusion area, RNV and the number of vascular endothelial nuclei that broke through the inner limiting membrane of the retina in the OIR group increased significantly, differences were statistically significant ( t=18.800, 9.025; P<0.05). Compared with the normal group, there were 54 miRNAs that were statistically differentially expressed in the OIR group, of which 47 were up-regulated and 7 were down-regulated. A total of 13 miRNAs related to p21 were screened from the alignment results of the three databases with the obtained differential miRNAs. According to the difference multiples, they were miR-7218-5p, miR-322-5p, miR-224-5p, miR-335-5p, miR-329-3p, miR-362-3p, miR-532-5p, miR-20b-5p, miR-20a-5p, miR-195a-5p, miR-423-5p, miR-497a-5p, and miR-129-5p. Differential miRNA target gene enrichment analysis yielded 1 112 go entries and 50 KEGG pathways, of which 50 go entries and 13 KEGG pathways were related to p21. Conclusion:13 miRNAs related to p21 were screened out in the OIR model.

Objective: To understand the experience and needs of elderly specialist nurses during the period of specialist training, and to provide reference and basis for the establishment of a more perfect training plan for elderly specialist nurses. Methods: A one-to-one in-depth interview was conducted among 5 students in the third training course of the Beijing Nursing Society with the method of phenomenological research. Colaizzi undefineds seven-step data method of phenomenology was used to analyze the results. Results: Five topics were abstracted from the experience of training aged specialist nurses, including stress, safety awareness, harvest and growth, professional pride, teaching teachersundefined views and suggestions on scientific research. Conclusions The curriculum setup of elderly specialist nurses needs to be optimized. It is necessary to strengthen the training of scientific research, optimize the teachersundefined strength and perfect the training means, and the managers should formulate the specialty and standardization of the elderly nursing as soon as possible. To provide the necessary support for the training of elderly specialist nurses.

Objective To investigate the expression of gastric and intestinal phenotypic markers in Siewert typeⅡand Ⅲ early gastroesophageal junction(GEJ) cancer, and to explore its correlation with clinic-pathological features.Methods From April 2010 to July 2015, 53 cases diagnosed as early GEJ cancer were enrolled.The gastric and intestinal phenotypic markers such as mucin5AC(MUC5AC),mucin6(MUC6),mucin2(MUC2),caudal related homeodomain transcription 2(CDX2) and cluster of differentiation 10(CD10) were detected, and then the patients were divided into gastric type, gastrointestinal type, intestinal type and non-classified type according to the results of immunohistochemical staining.Combined with Siewert classification the clinicopathological features were analyzed.Chi square test or Fisher′s exact test was performed for statistical analysis.Results In the cancer tissues of 47 patients with Siewert type Ⅱand Ⅲ early GEJ cancer, the case numbers of positive expression of MUC5AC,MUC6,MUC2, CDX2 and CD10 were 21(44.7%),19(40.4%),31(66.0%),27(57.4%) and 17(36.2%),respectively;the case numbers of gastric type, gastrointestinal type, intestinal type and non-classified type were 11(23.4%),14(29.8%),21(44.7%) and one(2.1%), respectively.The positive expression rates of MUC5AC and MUC6 in Siewert typeⅡwere 55.9%(19/34) and 50.0%(17/34),which were higher than those of Siewert typeⅢ(2/13), and the positive expression rate of MUC2 was 55.9%(19/34), which was lower than that of Siewert typeⅢ(12/13), and the differences were statistically significant (x2=6.240,4.679 and 4.053;all P<0.05).In Siewert typeⅡ, the proportion of intestinal type was 32.4%(11/34), which was lower than that of Siewert typeⅢ(10/13), and the differences were statistically significant (x2=7.142,P=0.010).In patients with Siewert typeⅡand Ⅲ early cancer, males predominated in intestinal type which were mostly well differentiated type with less submucosal carcinoma.The maximum diameter of tumor was less than those of gastric type and gastrointestinal type.In paracancerous mucosal tissues, the incidences of intestinal metaplasia in gastrointestinal type and intestinal type were 11/14 and 81.0%(17/21), which were higher than that of gastric type (3/11);the incidences of atrophy in gastrointestinal type and intestinal type were 12/14 and 85.7%(18/21),which were higher than that of gastric type (4/11),and the differences were statistically significant (Fisher′s exact test,all P<0.05).Conclusions Siewert typeⅡand Ⅲ early GEJ cancer can directly originated not only from gastric mucosa, but also from gastrointestinal and intestinal mucosa.Atrophy and intestinal metaplasia could exist before cancer genesis.

Objective To improve the success rate of puncture among senile patients with difficulties in venipuncture by applying the near-infrared visualization puncture technology.Methods This study selected 160 elderly patients with difficulties in peripheral venipuncture of department of General Surgery and Geriatric Medicine Department by random sampling to carry out peripheral venipuncture at Xuanwu Hospital of Capital Medical University from June 2015 to December 2016. Those patients were divided into control group and observation group with the random number table, 80 patients in each group. Patients in control group received peripheral venipuncture by nurses' personal experience along with assessing vessel by routine visual method and touch method without any accessory equipment. Patients in observation group received peripheral venipuncture by the location of infrared vessel imager. The infrared vessel imager was used to evaluate the vessel shape and depth to understand vascular branches so as to locate target vessel. And then, this study compared the success rate, time and site of punctures between two groups.Results The success rate of first puncture of observation group was 91.25% significantly higher than that of control group (χ2=43.495,P<0.01). The puncture time [(3.7±1.8) min]of observation group was less than that of control group with a significant difference (t=4.629, P<0.01). In the aspect of site of punctures, there was 72.5% of patients with punctures in observation group in forearm vein higher than that in control group (χ2=46.920,P<0.01).Conclusions The near-infrared visualization puncture technology can improve the success rate of puncture in elderly patients with difficulties in peripheral venipuncture, short the puncture time and help to achieve forearm venipuncture with the first choice. This technology can also relieve the pain of elderly patients, save consumptive material cost and reduce nurses' pressure on puncture. It is worth to be used widely in clinical application.

BACKGROUND:Studies have shown that astrocytes participate not only in the passive metabolic and structural support, but also actively in the central nervous system information processing. OBJECTIVE:By observing the directionality and specificity of astrocyte fiber growth and synapse formation, to explore the possible mechanisms of astrocytes and neurons in the interaction. METHODS: Primary cels from the hippocampi of green fluorescent protein transgenic newborn mice were isolated and cultured, glial fibrilary acidic protein was used as specific marker for astrocytes in immunofluorescence staining, and then the results were observed and scanned by confocal microscope. RESULTS AND CONCLUSION:The elongation of astrocyte fibers was directional and specific, and terminated to the pyramidal cels nearby. The end of astrocyte fibers and pyramidal cels contributed to the synapse formation. However, not al the projections were toward the adjacent cels, and synapse-like structure was not only formed nearby. The results implicated that both astrocytes fiber elongation and synapse formation have the directionality and specificity, providing evidence for further studies on signal transduction between astrocytes and pyramidal cels.

Objective To study the feasibility of the self-made negative pressure drainage device used for postoperative drainage of thyroid surgery. Methods To sum up 98 cases experiences of device utilization, we analyzed the manufacturing technology and the key points. Results All cases acquired success, of which one case gained 750 ml draining liquid of maximum daily, the other 97 cases had 15 -160 ml/d draining liquid, 33 ml/d average, drainage time 24-72 h, of which>36 h 53cases,>36-48 h 42cases, >48 h and ≤72 h 3cases, and medial 34 h. Conclusions Self-made negative pressure drainage device is convenient, simple, inexpensive and reliable production, which is worth of clinical promotion.