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1.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-22276273

RESUMO

BackgroundIn early March 2022, a major outbreak of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant spread rapidly throughout Shanghai, China. Here we aimed to provide a description of the epidemiological characteristics and spatiotemporal transmission dynamics of the Omicron outbreak under the population-based screening and lockdown policies implemented in Shanghai. MethodsWe extracted individual information on SARS-CoV-2 infections reported between January 1 and May 31, 2022, and on the timeline of the adopted non-pharmacological interventions. The epidemic was divided into three phases: i) sporadic infections (January 1-February 28), ii) local transmission (March 1-March 31), and iii) city-wide lockdown (April 1 to May 31). We described the epidemic spread during these three phases and the subdistrict-level spatiotemporal distribution of the infections. To evaluate the impact on the transmission of SARS-CoV-2 of the adopted targeted interventions in Phase 2 and city-wide lockdown in Phase 3, we estimated the dynamics of the net reproduction number (Rt). FindingsA surge in imported infections in Phase 1 triggered cryptic local transmission of the Omicron variant in early March, resulting in the largest coronavirus disease 2019 (COVID-19) outbreak in mainland China since the original wave. A total of 626,000 SARS-CoV-2 infections were reported in 99.5% (215/216) of the subdistricts of Shanghai. The spatial distribution of the infections was highly heterogeneous, with 40% of the subdistricts accounting for 80% of all infections. A clear trend from the city center towards adjacent suburban and rural areas was observed, with a progressive slowdown of the epidemic spread (from 544 to 325 meters/day) prior to the citywide lockdown. During Phase 2, Rt remained well above 1 despite the implementation of multiple targeted interventions. The citywide lockdown imposed on April 1 led to a marked decrease in transmission, bringing Rt below the epidemic threshold in the entire city on April 14 and ultimately leading to containment of the outbreak. InterpretationOur results highlight the risk of widespread outbreaks in mainland China, particularly under the heightened pressure of imported infections. The targeted interventions adopted in March 2022 were not capable of halting transmission, and the implementation of a strict, prolonged city-wide lockdown was needed to successfully contain the outbreak, highlighting the challenges for successfully containing Omicron outbreaks. FundingKey Program of the National Natural Science Foundation of China (82130093). Research in contextO_ST_ABSEvidence before this studyC_ST_ABSOn May 24, 2022, we searched PubMed and Europe PMC for papers published or posted on preprint servers after January 1, 2022, using the following query: ("SARS-CoV-2" OR "Omicron" OR "BA.2") AND ("epidemiology" OR "epidemiological" OR "transmission dynamics") AND ("Shanghai"). A total of 26 studies were identified; among them, two aimed to describe or project the spread of the 2022 Omicron outbreak in Shanghai. One preprint described the epidemiological and clinical characteristics of 376 pediatric SARS-CoV-2 infections in March 2022, and the other preprint projected the epidemic progress in Shanghai, without providing an analysis of field data. In sum, none of these studies provided a comprehensive description of the epidemiological characteristics and spatiotemporal transmission dynamics of the outbreak. Added value of this studyWe collected individual information on SARS-CoV-2 infection and the timeline of the public health response. Population-based screenings were repeatedly implemented during the outbreak, which allowed us to investigate the spatiotemporal spread of the Omicron BA.2 variant as well as the impact of the implemented interventions, all without enduring significant amounts of underreporting from surveillance systems, as experienced in other areas. This study provides the first comprehensive assessment of the Omicron outbreak in Shanghai, China. Implications of all the available evidenceThis descriptive study provides a comprehensive understanding of the epidemiological features and transmission dynamics of the Omicron outbreak in Shanghai, China. The empirical evidence from Shanghai, which was ultimately able to curtail the outbreak, provides invaluable information to policymakers on the impact of the containment strategies adopted by the Shanghai public health officials to prepare for potential outbreaks caused by Omicron or novel variants.

2.
Chinese Journal of Digestion ; (12): 159-164, 2021.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-885740

RESUMO

Objective:To analyze the reflux parameters of patients with gastroesophageal reflux disease (GERD) in upright position, supine position and at 2 h after meals, and to explore the cut-off value, sensitivity and specificity of the reflux parameters in different positions and at 2 h after meals in GERD diagnosis.Methods:From January 2016 to July 2020, 200 GERD patients (GERD group) and 61 non-GERD patients (control group) who visited Huazhong University of Science and Technology Union Shenzhen Hospital (Former Nanshan District People′s Hospital), were selected. All the patients of the two groups received gastroesophageal reflux disease questionnaire (GERDQ), upper gastrointestinal endoscopy, esophageal high resolution manometry and 24 h esophageal pH combined impedance monitoring. T test, non-parametric test and chi-square test were used to compare the related parameters in upright position, supine position and at 2 h after meals between two groups and within each group. Receiver oparative characteristic (ROC) curves of reflux parameters in upright position, supine position and 2 h after meals were drawn to determine the cut-off value, sensitivity and specificity in GERD diagnosis. Results:The proportion of patients with acid reflux in supine position of the control group was higher than that of the GERD group (41.0%, 25/61 vs. 8.50%, 17/200), and the difference was statistically significant ( χ2=36.53, P<0.01). In the control group, the acid reflux time in upright position, number of acid reflux, acid exposure time (AET), longest reflux time and number of weak acid reflux were more than those of in supine position in the same group (6.00 min(2.00 min, 13.50 min) vs. 0.00 min(0.00 min, 1.50 min), 16.00(8.00, 27.00) vs. 1.00(0.00, 3.00), 0.90%(0.33%, 1.88%) vs. 0.00%(0.00%, 0.30%), 2.00 min(1.00 min, 4.00 min) vs. 0.00 min(0.00 min, 1.00 min), 7.00(3.00, 11.00) vs. 1.00(0.00, 2.00), respectively) and the differences were statistically significant ( Z=5.43, 6.61, 5.06, 3.58 and 6.24, all P<0.01). In the GERD group, the acid reflux time, number of acid reflux, AET, longest reflux time and number of weak acid reflux in upright position were higher than those in supine position (51.00 min, (31.00 min, 86.75 min) vs. 8.00 min(1.00 min, 42.00 min), 60.00(48.00, 83.75) vs.6.00(2.00, 19.50), 7.30%(3.90%, 12.10%) vs. 1.50%(0.20%, 6.50%), 7.00 min(4.00, 12.00 min) vs. 4.00 min(1.00 min, 17.00 min), 1.00(0.00, 3.00) vs. 0.00(0.00, 2.00), 7.00(3.00, 12.00) vs. 0.00(0.00, 1.00), respectively) and the differences were statistically significant ( Z=7.92, 11.22, 6.90, 2.56, 5.11 and 11.76, all P<0.05). The acid reflux time, number of acid reflux, AET, longest reflux time and number of weak acid reflux at 2 h postprandial were 3.00 min(2.00 min, 9.00 min), 10.00(5.00, 18.00), 0.90%(0.40%, 1.98%), 1.00 min(0.00 min, 3.00 min), 4.00(1.50, 8.50)and 28.50 min(15.00 min, 54.75 min), 35.00(24.00, 52.00), 8.30%(4.32%, 15.83%), 6.00 min(3.00 min, 11.00 min), 4.00(2.00, 7.25), in the control and GERD groups, respectively, which were significantly higher than those in supine position in the same group ( Z=4.30, 6.33, 5.50, 3.40, 5.71 and 3.76, 9.21, 5.76, 1.97, 10.46, all P<0.05). Among 200 GERD patients, 125 patients had symptoms recorded during the 24 h esophageal pH combined impedance monitoring, the incidence of reflux symptoms in upright position was higher than that in supine position (89.6%, 112/125 vs. 65.6%, 82/125), and the difference was statistically significant ( χ2=20.71, P<0.01). The results of ROC curve analysis showed that the accuracy of acid reflux time in upright position in GERD prediction was the highest, with AUC value of 0.94 and cut-off value of 24.5 min, and the sensitivity and specificity in GERD diagnosis were 81.50% and 95.08%, respectively. The prediction accuracy of acid reflux times in upright position and AET in upright position for GERD was secondary, AUC value both were 0.93 and the cut-off value of the acid reflux number in upright position was 39.5, and the sensitivity and specificity in GERD diagnosis were 84.00% and 95.08%, respectively. The cut-off value of AET in upright position was 2.75%, the sensitivity and specificity in GERD diagnosis were 85.00% and 93.33%, respectively. The AUC value, cut-off value, sensitivity and specificity of AET at 2 h postprandial were 0.91, 4.60%, and 73.49% and 95.00%, respectively. Conclusions:Both GERD patients and non-GERD patients have more reflux in upright position, especially within 2 h after meals. The diagnostic values of acid reflux time in upright position, number of acid reflux, AET and AET 2 h after meals for GERD is high, and the AUC values are all >0.90, which can be used as a more comprehensive basis for the analysis and diagnosis of GERD.

3.
Chinese Journal of Urology ; (12): 61-63, 2017.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-667266

RESUMO

Objective We used the dataset base on high throughput sequencing data to construct a diagnosis model by ANN and GA.Methods We screened the Taylor_prostate datasets from GEO according to,then we used the GA to screen the datas further. Finally we used the ANN to analyze the datas and construct a diagnosis model. To validate the model,we used 10-folds crossvalidation as the inner validation and the datas from Grasso dataset( GPL6480 and GPL6848) were used as the outter validation.Results We got 5 genes ACADL,ACTG2, CACNA2D1,PCP4 and SPARCL1.And we used spss to get the AUC of the model which is 94.62.The result of validation is good.Conclusion The performance of the model is good because the AUC is larger than 0.5.

4.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-571818

RESUMO

Objective To investigate the effects of Cholera Toxin(CTx)on the cAMP level and the survival as well as the apoptosis of retinal ganglion cells (RGCs) after distal axotomy of the optic nerve.Method After transecting the optic nerve intracranially, CTx was injected intravitreally. Fluorescent retrograde tracing method and TUNEL(TdT-mediated dUTP nick end labeling)technique were used to show the surviving RGCs and the apoptotic cells in the ganglion cell layer. The Brown's radioimmunoassay method was used to measure the cAMP level of the retina. Result The cAMP level of the normal retina was 6.22?2.02pmol/g/retina. The mean density of RGCs in the normal retina was 2 192?66/mm 2 and it decreased to 1 520?116/mm 2、736?39/mm 2 and 466?53/mm 2 at 1W、2W and 3W respectively after distal axotomy. The densities of RGCs in the distal axotomy groups treated with CTx and killed at 1W、2W and 3W were 1 642?122/mm 2、1 091?107/mm 2、 748?35/mm 2 respectively and were significantly higher than those of distal axotomy group without CTx treatment. Conclusions The results show that CTx can elevate cAMP level of the retina and promote the survival of RGCs and inhibit the apoptosis of RGCs after distal axotomy of the optic nerve in adult hamsters.

5.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-681930

RESUMO

Objective The present study was aimed at investigating the regeneration promoting mechanism of forskolin and IBMX on injured retinal ganglion cells(RGCs). Methods Fluorescent retrograde labeling and autologus sciatic nerve transplanting techniques were used to observe the effects of H 89 or/and wortmannin on the regeneration promoting effects of forskolin and IBMX on injured retinal ganglion cells by intravitreal injection. Results Both H 89 and wortmannin could partly block the promoting effects of forskolin and IBMX on regeneration of injured RGCs, the effects of wortmannin might be more powerful, if united, they could inhibit the effects of forskolin and IBMX completely.Conclusion The regeneration promoting effects of forskolin and IBMX on injured RGCs might be realized by PKA CREB and PI3 K Akt accesses.

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