RBC-hitchhiking chitosan nanoparticles loading methylprednisolone for lung-targeting delivery.

Hyper-inflammation associated with cytokine storm syndrome causes high mortality in patients with COVID-19. Glucocorticoids, such as methylprednisolone sodium succinate (MPSS), effectively inhibit this inflammatory response. However, frequent and chronic administration of glucocorticoids at high doses leads to hormone dependence and serious side effects. The aim of the present study was to combine nanoparticles with erythrocytes for the targeted delivery of MPSS to the lungs. Chitosan nanoparticles loading MPSS (MPSS-CSNPs) were prepared and adsorbed on the surface of red blood cells (RBC-MPSS-CSNPs) by non-covalent interaction. In vivo pharmacokinetic study indicated that RBC-hitchhiking could significantly reduce the plasma concentration of the drug and prolong the circulation time. The mean residence time (MRT) and area under the curve (AUC) of the RBC-MPSS-CSNPs group were significantly higher than those of the MPSS-CSNPs group and the MPSS injection group. Moreover, in vivo imaging and tissue distribution indicated that RBC-hitchhiking facilitated the accumulation of nanoparticles loading fluorescein in the lung, preventing uptake of these nanoparticles by the liver. Furthermore, compared with the MPSS-CSNPs and MPSS treatment groups, treatment with RBC-MPSS-CSNPs considerably inhibited the production of inflammatory cytokines such as TNF-α and IL-6, and consequently attenuated lung injury induced by lipopolysaccharide in rats. Therefore, RBC-hitchhiking is a potentially effective strategy for the delivery of nanoparticles to the lungs for the treatment of acute lung injury and acute respiratory distress syndrome.

Using "compartment model" dynamics to understand the transmission regularity of coronavirus disease 2019 (COVID-19) during the outbreak period

Since the outbreak of coronavirus disease 2019 (COVID-19) on a large scale in late January 2020, the relevant reports of COVID-19 dynamics modeling found that it was very important to establish an appropriate data collection system and scientifically deal with massive information for epidemic control. No matter in theory or in practice, the transmission and treatment of virus infected persons with the kind of nonlinear epidemic diseases are affected by various factors, multiple levels, and different prevention and control measures. After confirming the transmission route of "human-to-human transmission", the data change rules of confirmed cases and new cases of infectious population in China and in the early stage of the outbreak I - 40 d after the closure of Wuhan were analyzed. China has quickly adopted measures to control the spread of the virus, such as "city closure", "isolation", and "wearing masks", and has achieved phased success. In order to scientifically determine the degree of harm of infectious diseases, a simplified "two-compartment" model of "transmission phase" and "disposition phase" is proposed and analyzed based on domestic and international epidemic data. It is more practical to study the speed of virus transmission and the dynamics analysis to control the outbreak. Acceding to data from the Global Epidemic l'invonian Consulting Center and WHO. the growth Me 041 and doubling time of the total number of confirmed caws and the number of confirmed cases from the two sources have little change. The study found that the global propagation doubling time is significantly shorter than 6.27 - 7.03 d in China. indicating that the global propagation rate is significantly higher than that in China. K. fir and atonality rate of the total number of confined eases in Italy. Spain. and Iran are obviously different from the global data. The special mortality:ate is significantly higher than the global level, with 9.576s. 6.59%. and 7. Sets respectively. which is alined twice that of the world. Therefore. the study believes that it is the key to deal with the transmission pathway and could of the transmission rate.

A smartphone-based online tool for prehospital self-triage of COVID-19.

The COVID-19 epidemic has swept across China and spread to other countries. The rapid spreading of COVID-19 and panic combined with the lack of a hierarchical medical system in China have resulted in a huge number of hospital visiting which are overwhelming local medical system and increasing the incidence of cross infection. To meliorate this situation, we adopted the management concept of the system of Tiered Diagnosis and Treatment and developed an online tool for self-triage based on the mostly used multi-purpose smartphone app Wechat in China. This online tool helps people perform self-triage so that they can decide whether to quarantine at home or visit hospital. This tool further provides instructions for home quarantine and help patients make an appointment online if hospital visiting suggested. This smartphone application can reduce the burden on hospitals without losing the truly COVID-19 patients and protect people from the danger of cross infection.

Analysis of 4 imaging features in patients with COVID-19.

BACKGROUND: The aim of this was to analyze 4 chest CT imaging features of patients with coronavirus disease 2019 (COVID-19) in Shenzhen, China so as to improve the diagnosis of COVID-19. METHODS: Chest CT of 34 patients with COVID-19 confirmed by the nucleic acid test (NAT) were retrospectively analyzed. Analyses were performed to investigate the pathological basis of four imaging features("feather sign","dandelion sign","pomegranate sign", and "rime sign") and to summarize the follow-up results. RESULTS: There were 22 patients (65.2%) with typical "feather sign"and 18 (52.9%) with "dandelion sign", while few patients had "pomegranate sign" and "rime sign". The "feather sign" and "dandelion sign" were composed of stripe or round ground-glass opacity (GGO), thickened blood vessels, and small-thickened interlobular septa. The "pomegranate sign" was characterized as follows: the increased range of GGO, the significant thickening of the interlobular septum, complicated with a small amount of punctate alveolar hemorrhage. The "rime sign" was characterized by numerous alveolar edemas. Microscopically, the wall thickening, small vascular proliferation, luminal stenosis, and occlusion, accompanied by interstitial infiltration of inflammatory cells, as well as numerous pulmonary interstitial fibrosis and partial hyaline degeneration were observed. Repeated chest CT revealed the mediastinal lymphadenectasis in one patient. Re-examination of the NAT showed another positive anal swab in two patients. CONCLUSION: "Feather sign" and "dandelion sign" were typical chest CT features in patients withCOVID-19; "pomegranate sign" was an atypical feature, and "rime sign" was a severe feature. In clinical work, accurate identification of various chest CT signs can help to improve the diagnostic accuracy of COVID-19 and reduce the misdiagnosis or missed diagnosis rate.

Infection Control against COVID-19 in Departments of Radiology.

The COVID-19 epidemic, which is caused by the novel coronavirus SARS-CoV-2, has spread rapidly to become a world-wide pandemic. Chest radiography and chest CT are frequently used to support the diagnosis of COVID-19 infection. However, multiple cases of COVID-19 transmission in radiology department have been reported. Here we summarize the lessons we learned and provide suggestions to improve the infection control and prevention practices of healthcare workers in departments of radiology.

Corona Virus International Public Health Emergencies: Implications for Radiology Management.

The outbreak of 2019 novel coronavirus (2019-nCoV) pneumonia was reported in Wuhan, Hubei Province, China in December 2019 and has spread internationally. This article discusses how radiology departments can most effectively respond to this public health emergency.