Background: A considerable proportion of patients hospitalized with corona virus disease 2019 (COVID-19) have acquired secondary bacterial infections (SBIs). We report the etiology and antimicrobial resistance of bacteria to provide theoretical basis for appropriate infection therapy.Methods: In the retrospective study, we reviewed electronic medical records of all the patients hospitalized with COVID-19 in the Wuhan Union hospital from January 27 to March 17, 2020. According to the inclusion and exclusion criteria, patients who acquired SBIs were enrolled. Demographic, clinical course, etiology and antimicrobial resistance data of the SBIs were collected. Outcomes were also compared between patients who were classified as severe on admission and those who were classified as critical.Results: 6.8% (102/1495) of the patients with COVID-19 had acquired SBIs and almost half of them (50, 49.0%) died during hospitalization. Compared with the severe patients, the critical patients had a higher chance of SBIs. 159 strains of bacteria were isolated, 85.5% of which were Gram-negative bacteria. The top three bacteria of SBIs were A. baumannii (35.8%), K. pneumoniae (30.8%) and Staphylococcus (8.8%). The isolation rate of carbapenem-resistant A. baumannii and K. pneumoniae were 91.2% and 75.5%, respectively. Meticillin resistance was in 100% of Staphylococcus, and vancomycin resistance was not found. Conclusions: SBIs may occur in patients hospitalized with COVID-19 and lead to high mortality. The incidence of SBIs was associated with the grade on admission. Gram-negative bacteria, especially A. baumannii and K. pneumoniae, were the main bacteria and the resistance rates of the major isolated bacteria were generally high.

Mast cell (MC) degranulation is the foundation of the acute phase of allergic rhinitis (AR). Previously, downregulation of GATA binding protein 3 (GATA-3) was shown to suppress MC activation in an AR mouse model. Binding of microRNA-135a (miR-135a) to GATA-3 was also observed, and overexpression of this miRNA decreased GATA-3 mRNA and protein expression. However, the effects of miR-135a on MCs during AR are currently unknown. In the present study, we utilized a lentiviral (LV) vector to intranasally administer miR-135a to ovalbumin (OVA)-sensitized AR mice. Following miR-135a treatment, the total serum IgE concentration observed during AR was significantly reduced. In the nasal mucosa, the expression of T-box expressed in T cells (T-bet) was higher, whereas that of GATA-3 was lower in the AR mice following miRNA treatment. Notably, during AR, the ratio of type 1 T-helper cells (Th1) to type 2 (Th2) cells in the spleen is unbalanced, favoring Th2. However, administering miR-135a to the AR mice appeared to balance this ratio by increasing and decreasing the percentage of Th1 and Th2 cells, respectively. MiR-135a also appeared to strongly suppress the infiltration of eosinophils and MCs into the nasal mucosa, and it was specifically localized in the MCs, suggesting that its influence is modulated through regulation of GATA-3 in these cells. Additional work identifying the full therapeutic potential of miR-135a in the treatment of AR and diseases involving allergen-induced inflammation is warranted.

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Logistics planning is a critical part of developing supply chain for modular integrated construction (MiC) projects in Hong Kong where high-rise, high density and hilly landscape is the norm. It is important to minimize the total logistics and to guarantee timely delivery of modules, especially for several MiC projects being constructed during the same period. Nevertheless, there is a significant lack of studies on logistics planning, optimization and visualization for MiC projects. The aim of this paper is to establish an integrated MiC logistics planning and visualization platform, which is grounded on the integration of building information modeling (BIM), geographical information system (GIS) and vehicle routing problem (VRP) algorithm. The framework is then presented and evaluated using a case study to identify optimal logistics scenario of trailer routes to meet the installation time window of MiC projects in Hong Kong. The paper finds that the proposed platform has the ability to make optimized logistics scenario for MiC projects, and to visualize the logistics scenario in a 3-dimentional interactive environment. Future study will focus on adopting flexible control strategies and including more decision-making criteria of logistics planning in MiC projects such as road width limitation, travel speed and different module types