Background: Strict countermeasures for coronavirus disease (COVID-19) were undertaken in China without knowing their influence on asthma.Objective: To investigate the associations between the frequencies of asthma exacerbations and respiratory infections and air pollutants before and during the COVID-19 pandemic, which were direct consequences of countermeasures undertaken for the pandemic.Methods: Asthma exacerbations and respiratory infections among hospitalized children in the permanent population of Guangzhou City, China, from February to June 2016-2019 (before the pandemic) to February to June 2020 (during the pandemic) were collected in this cross-sectional study in Guangzhou.Results: The number of asthma exacerbation cases per month documented in the Guangzhou Women and Children's Hospital before (median: 13.5; range: 0-48) and during (median: 20; range: 0-34) the mitigative response to the COVID-19 pandemic was similar. The frequency of severe asthma exacerbation cases per month decreased, whereas that of mild asthma exacerbation cases per year increased (p = .004). The number of patients hospitalized with infectious respiratory diseases decreased from 146 (range: 90-172) per month before the pandemic to 42 (range: 33-57) per month during the pandemic (p = .004). Most pathogens and air pollutants decreased during the COVID-19 pandemic. The frequency of severe asthma exacerbations positively correlated to that of respiratory infections in children, but did not correlate to air pollutants. Conclusion:Strict countermeasures undertaken for the pandemic were associated with a decreased the frequency of infectious respiratory diseases and severe asthma exacerbations among urban children.

Abstract. Recepteur d'origine nantais (RON) is a receptor tyrosine kinase (RTK) normally expressed at low levels in epithelial cells. RON is a 180-kDa heterodimeric protein composed of a 40-kDa α-chain and a 150-kDa transmembrane β-chain with intrinsic tyrosine kinase activity. The extracellular sequences of RON contain several domains including an N-terminal semaphorin (sema) domain, followed by the plexin, semaphorin, integrin (PSI) domain, and four immunoglobulin, plexin, transcription factor (IPT) domains. Here, we identified RON genes from 14 vertebrate genomes and found that RON exists in all types of vertebrates including fish, amphibians, birds and mammals. We found that the human RON gene showed predominant expression in the liver, lymph node, thymus, intestine, lung, mammary gland, bone marrow, brain, heart, placenta, bladder, cortex, cervix, skin, kidney and prostate. When searched in the PrognoScan database, human RON was also found to be expressed in bladder, blood, breast, glioma, esophageal, colorectal, head and neck, ovarian, lung and skin cancer. The relationship between the expression of RON and prognosis was found to vary in different cancer types, even in the same cancer from different databases. This suggests that the function of RON in these tumors may be multidimensional, not just as a tumor suppressor or oncogene. Six available single-nucleotide polymorphisms (SNPs) disrupting existing exonic splicing enhancers were identified in RON. This may contribute to the generation of active RON variants by alternative splicing, which is frequently observed in primary tumors.

ABSTRACT.Objective: To investigate the ocular hypertensive response to topical dexamethasone (DEX), rimexolone (RIM), loteprednol etabonate (LOT) and fluorometholone (FML) in rabbits of different ages. Methods: Seventy-five rabbits of three age groups (7 weeks, 6 months and 1-year old) received topical administration of 0.1% DEX, 1% RIM, 0.5% LOT, 0.1% FML or balanced salt solution four times daily for 1 month. Intraocular pressure (IOP) was monitored at regular time intervals. After a month, eyes were harvested for histological study with haematoxylin and eosin (H&E), periodic acid Schiff and Masson trichrome staining. Trabecular meshwork changes were graded by masked ocular pathologists. Results: Topical DEX caused the greatest increase in IOP, followed by RIM and FML. LOT caused the least IOP increase. Similar pattern of IOP response to the four corticosteroids was observed in the three studied age groups. Young rabbits (7 week) were the most responsive to corticosteroids among the age groups. Extracellular matrix thickening in the trabecular meshwork region and loss of trabecular meshwork cells were observed after DEX, FML or RIM treatments. Conclusion: Young rabbits are more susceptible to steroid induced increase in IOP, even for milder steroids such as fluorometholone and rimexolone.

No abstract