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BackgroundAn outbreak of COVID-19 occurred on the Diamond Princess cruise ship in January and February 2020. We analysed information about cases to infer transmission dynamics and potential modes of transmission. MethodsWe collected the daily number of 197 symptomatic cases, and that of the 146 passenger cases in two categories, i.e. those who stayed and did not stay in the same stateroom. We retrieved the quarantine details and the ships 14-day itinerary. We searched the websites of national/local health authority along the cruise routes and local news using Google for locally confirmed cases associated with the ship. We obtained the design of air conditioning and sewage treatment of the ship from literature. We back-calculated the dates of infection from the epidemic curve and compared with the start of on-board quarantine. ResultsMajor infections started on Jan 28 and completed by Feb 6 for passengers except those who stayed in the same stateroom with infected individual(s). No other confirmed cases were identified among the disembarked people in Hong Kong except an 80 years old passenger. No confirmed cases were reported in three other stopovers between Jan 27-31 associated with disembarked passengers or visitors from the ship, however two Okinawa taxi drivers became confirmed cases in association with driving the ship passengers. Infection among passengers after Feb 6 was limited to those who stayed in the same stateroom with an infected passenger. Infections in crew members peaked on Feb 7, suggesting significant transmission among crew members after quarantine on Feb 5. ConclusionsWe infer that the ship central air conditioning system did not play a role, i.e. the long-range airborne route was absent in the outbreak. Most transmission appears to have occurred through close contact and fomites. Significance StatementTransmission by the long-range airborne route for SARS-CoV-2 in the 2020 Diamond Princess Covid-19 outbreak has been debated with significant implication for intervention. We found that the transmission by close contact and fomite explains the outbreak, and the central air-conditioning system did not play a role, demonstrating the importance of social distancing, good hygiene and maintaining good building ventilation for intervention.
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Objective An interaction network among PD-1-ligands and other proteins were built to add deeper understanding of PD-1 signal pathway and to supply the theoretical data on the clinical application study of PD-1 and its ligands.Methods Searching the literature about PD-1 and its ligands in the PubMed,the result of which would be used to summarize the proteins that had been reported to have interactions with PD-1 and its ligands,and then,quadratic search would be performed on these proteins.Finally,the software Cytoscape would be used to build and analyze the interaction network and verified by PCR.Results There were 122 and 126 nodes in the PD-1/PD-L1 network and PD-1/PD-L2 network respectively.These proteins were involved in TCR signal path-way,cell adhesion,JAK-STAT signal pathway and interaction between cytokines.Meanwhile,a perspective that PD-L1 may influ-ence on CXCR4 through JAK-STAT pathway based on the network which had been supported by qPCR.Conclusion The bioinfor-matics suggested that there are differences between the mechanism of PD-1/PD-L1 and PD-1/PD-L2.Additionally,the method, which was based on the literature mining and bioinformatics,is good to put the biological literature to rational utilization and to pro-vide guidance for experiments.
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There is no sufficient data to conclude the benefit of assisted hatching (AH) for advanced age patients. However, AH is routinely performed for advanced age patients undergoing in vitro fertilization (IVF) in China based on some retrospective evidence. It is important to assess the benefit of AH procedure for advanced age patients, especially by analyzing the data from China. This is a prospective randomized controlled trial to evaluate the effect of laser AH in the advanced age patients undergoing IVF. A total of 256 patients conformed to the inclusion criteria, and 78 were excluded by exclusion criteria. A total of 178 patients were eligible and randomized to 2 groups (82 AH group and 96 control group). Laser AH (zona thinning) was performed in the AH group. There were no statistical significance in basic clinical parameters between the 2 groups. No difference was found in implantation rate (AH vs control, 32.45% vs 39.29%) and clinical pregnancy rate (AH vs control, 48.78% vs 59.38%). Our data did not find any benefit of laser AH in improving implantation or pregnancy rates in advanced age women. Due to the potential risk and increasing financial burden, AH should not be routinely performed in first fresh IVF embryo transfer cycle for advanced age women.
Subject(s)
Embryo Implantation , Fertilization in Vitro/methods , Laser Therapy/methods , Pregnancy Rate , Adult , Female , Humans , Pregnancy , Prospective Studies , Zona Pellucida/radiation effectsABSTRACT
Objective To evaluate the feasibility, efficacy and safety of new nano material occluder of single rivet type (left-disk with no-hub) in treating ventricular septal defect (VSD) in order to provide experimental basis for clinical application. Methods A total of 26 healthy adult dogs were selected for this study . Under thoracotomy , VSD model was established through fluoroscopically-guided percutaneous puncturing of the right ventricular free wall. The models were randomly and equally divided into the study group(n=13, using nano material VSD occluder) and the control group(n=13, using double-hub nitinol occluder). Every two dogs from each group were sacrificed each time at one, 2, and 3 months after percutaneous closure of VSD with corresponding occluder, the tissue samples were collected and sent for gross examination as well as for the optical and electronic microscopy study;the blood concentration of nickel ion was also determined. The state of endothelialization after implantation of the new type occluder was evaluated, and the complications such as residual shunt and superficial thrombus formation were recorded. The results were analyzed. Results By open chest operation with small incision and percutaneous puncturing of the right ventricular free wall, VSD model was successfully established in all 26 dogs. The success rate of the implantation of the VSD occluder in the study group was 100%, while it was 91.7% in the control group. One, 2, 3 and 6 months after the implantation, the heart specimens of 25 dogs were removed and gross examination showed that neither occluder displacement nor alloy wire fracture occurred in both groups. No thrombus formation or vegetation attached on the disk surface was observed. One month after the procedure , in the study group the bilateral disk surfaces of the occluder were covered with thin layer transparent tissue , which were proved to be composed of the fibrous tissue and endothelial cells through pathologic and electronic microscopy study. Six months after implantation, the superficial tissue of the occluder became further thickened and the occluder edge became fused with the surrounding heart tissue. Conclusion The design of the new VSD nano materials occluder, which has a left-disk with no hub, is very scientific. Compared with double-hub nitinol occluder, the new device can shorten the time of complete endothelialization and effectively occlude the VSD. Therefore, this new nano material occluder has promising prospect in clinical application.
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Objective To discuss the treatment mode of mass NBC casualties by field medical unit in NBC environment.Method Field medical unit rehearsed in a simulated NBC environment.Result The procedure for the rehearsal and treatment of field medical unit in NBC environment was determined.The importance of high-tech medical equipment for the obstructed patient flow was made clear.Conclusion High-tech medical equipment should be emphasized on to enhance the treatment capability of field medical unit.
