A pandemic of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection broke out all over the world; however, epidemiological data and viral shedding in pediatric patients are limited. We conducted a retrospective, Chun-Zhen Hua and Zi-Ping Miao contributed equally to this study.

The hedgehog signal pathway plays a crucial role in the angiogenesis and vascular remodeling. However, the function of this pathway in the pulmonary vascular smooth cell proliferation in response to hypoxia remains unknown. In this study, we have demonstrated that the main components of the hedgehog pathway, including sonic hedgehog (SHH), patched1 (PTCH1), smoothened (SMO), GLI and hypoxia-inducible factor 1 (HIF1) are expressed in the human pulmonary arterial smooth muscle cells (HPASMCs). Interestingly, hypoxia significantly enhanced the expression of SHH and HIF1, facilitated the translocation of GLI1 into the nuclei, and promoted the proliferation of HPASMCs. Furthermore, direct activation of the SHH pathway through incubation with the purified recombinant human SHH or with purmorphamine and SAG, two Smo agonists, also enhanced the proliferation of HPASMCs. Importantly, the treatment with anti-SHH and anti-HIF1 antibodies or cyclopamine, a specific SMO inhibitor, markedly inhibited the nuclear translocation of GLI1 and cell proliferation in the HPASMCs induced by hypoxia and activation of the SHH pathway. Moreover, the treatment with cyclopamine increased apoptosis in the hypoxic HPASMCs. These data strongly demonstrate for the first time that the SHH signaling plays a crucial role in the regulation of HPASMC growth in response to hypoxia.

AJs: adherens junctions; ALI: acute lung injury; ARDS: acute respiratory distress syndrome; ATG5: autophagy related 5; ATG12: autophagy related 12; ATG 16L1: autophagy related 16 like; 1 BALF: bronchoalveolar lavage fluidCQ: chloroquine; Ctrl: control; EC: endothelial cell; GFP: green fluorescent protein; HA-tagged; RAB26: HA-tagged wild-type; RAB26  HA-tagged; RAB26: HA-tagged; RAB26HA-tagged; RAB26: HA-tagged; RAB26HPMECs: human pulmonary microvascular endothelial cells; H&E: hematoxylin & eosin; IgG: immunoglobulin; GIF: immunofluorescence; IP: immunoprecipitationi;. p.: intraperitoneal; LPS: lipopolysaccharide; PBS: phosphate-buffered salinesi; RNA: small interfering;RNASQSTM1/p62, sequestosome; 1TBS: Tris-buffered saline; VEGF: vascular endothelial growth factor; WB: western blot; WT: wild-type.

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The small GTPase Rab26 is involved in multiple processes, such as vesicle-mediated secretion and autophagy. However, the mechanisms and functions of Rab26 in the human pulmonary microvascular endothelial cells (HPMVECs) are not clear. In this study, we thoroughly investigated the role and novel mechanism of Rab26 in permeability and apoptosis of HPMVECs using a self-assembled Rab26 siRNA loaded DNA Y-motif nanoparticle (siRab26-DYM) and Rab26 adenovirus. We found that siRab26-DYM could be efficiently transfected into HPMVECs in a time- and dose-dependent manner. Importantly, the siRab26-DYM nanovector markedly aggravated the LPS-induced apoptosis and hyper-permeability of HPMVECs by promoting the nuclear translocation of Foxo1, and subsequent activation of Toll-like receptor 4 (TLR4) signal pathway. Overexpression of Rab26 by Rab26 adenoviruses partially inactivated LPS-induced TLR4 signaling pathway, suppressed the cell apoptosis and attenuated the hyperpermeability of HPMVECs. These results suggest that the permeability and apoptosis of HPMVECs can be modulated by manipulating Rab26 derived TLR4 signaling pathway, and that Rab26 can be potential therapeutic target for the treatment of vascular diseases related to endothelial barrier functions.

Objective To investigate the clinical features and risk factors for discerning the critical and predicting the outcome of patients with COVID‐19. Methods Patients who were admitted to the intensive care unit (ICU) department and general infection department of TaiKang Tongji (Wuhan) Hospital from February 10 to March 27, 2020, were included. Data on clinical features, complications, laboratory parameters, chest CT, nutrient requirement, and electrolyte imbalance were analyzed retrospectively. Results A total of 123 (50 critical and 73 non‐critical) patients were enrolled. 65% of patients with comorbidities, hypertension (45.5%), diabetes (21.9%), 36.5% of patients had more than one comorbidity. The proportion of lymphocytes in critical patients was significantly lower than that of non‐critical patients. The proportion of patients with increased NLR, PLR, IL‐6, CRP levels, and chest CT score was significantly higher in the critical than that of non‐critical patients. The logistic regression analysis identified low lymphocyte count, high NLR, PLR, IL‐6, CRP levels, and CT score as independent factors for discerning critical cases and high NLR, PLR, IL‐6, and CT score could predict poor clinical outcome. Furthermore, we identified patients who needed nutrition support (HR 16.99) and with correction of electrolyte imbalance (HR 18.24) via intravenous injection were more likely to have a poor outcome. Conclusions The potential risk factors of lower lymphocyte count, high levels of NLR, PLR, IL‐6, CRP, chest CT score, and the statue of nutrient requirement or electrolyte imbalance could assist clinicians in discerning critical cases and predict the poor outcome in patients with COVID‐19.

Programmable DNA nanostructures are a new class of biocompatible, nontoxic nanomaterials. Nevertheless, their application in the field of biomedical research is still in its infancy, especially as drug delivery vehicles for gene therapy. In this study, a GTPase Rab26 was investigated as a new potential therapeutic target using a precisely tailored DNA nanoprism for targeted lung cancer therapy. Specifically, a DNA nanoprism platform with tunable targeting and siRNA loading capability is designed and synthesized. The as‐prepared DNA prisms were decorated with two functional units: a Rab26 siRNA as the drug and MUC‐1 aptamers as a targeting moiety for non‐small cell lung cancer. The number and position of both siRNA and MUC‐1 aptamers can be readily tuned by switching two short, single‐stranded DNA. Native polyacrylamide gel electrophoresis (PAGE) and dynamic light scattering technique (DLS) demonstrate that all nanoprisms with different functionalities are self‐assembled with high yield. It is also found that the cellular uptake of DNA prisms is proportional to the aptamer number on each nanoprism, and the as‐prepared DNA nanoprism show excellent anti‐cancer activities and targeting capability. This study suggests that by careful design, self‐assembled DNA nanostructures are highly promising, customizable, multifunctional nanoplatforms for potential biomedical applications, such as personalized precision therapy.

Background The novel coronavirus disease 2019 (COVID-19) spreads rapidly among people and causes a pandemic. It is of great clinical significance to identify COVID-19 patients with high risk of death. Methods A total of 2169 adult COVID-19 patients were enrolled from Wuhan, China, from February 10th to April 15th, 2020. Difference analyses of medical records were performed between severe and non-severe groups, as well as between survivors and non-survivors. In addition, we developed a decision tree model to predict death outcome in severe patients. Results Of the 2169 COVID-19 patients, the median age was 61 years and male patients accounted for 48%. A total of 646 patients were diagnosed as severe illness, and 75 patients died. An older median age and a higher proportion of male patients were found in severe group or non-survivors compared to their counterparts. Significant differences in clinical characteristics and laboratory examinations were found between severe and non-severe groups, as well as between survivors and non-survivors. A decision tree, including three biomarkers, neutrophil-to-lymphocyte ratio, C-reactive protein and lactic dehydrogenase, was developed to predict death outcome in severe patients. This model performed well both in training and test datasets. The accuracy of this model were 0.98 in both datasets. Conclusion We performed a comprehensive analysis of COVID-19 patients from the outbreak in Wuhan, China, and proposed a simple and clinically operable decision tree to help clinicians rapidly identify COVID-19 patients at high risk of death, to whom priority treatment and intensive care should be given.