Background. Linxian, China, has some of the highest rates of esophageal cancer in the world. Previous authors have proposed that esophagitis, atrophy, and dysplasia may be precursor lesions of esophageal cancer in such high risk populations. Methods. To examine the relationship between squamous esophageal histology and subsequent esophageal cancer in Linxian, the authors prospectively followed 682 participants of a 1987 endoscopic survey for 3.5 years and compared their initial biopsy diagnoses with the occurrence of squamous cell carcinoma during this follow‐up period. Results. Squamous cell carcinoma of the esophagus was identified in 52 (7.6%) of the participants during the follow‐up period. After adjusting for potential confounding factors, relative risks (95% confidence intervals) for squamous cell carcinoma incidence by initial histologic diagnoses were as follows: normal, 1.0 (reference); basal cell hyperplasia, 2.1 (0.4‐9.8); mild dysplasia, 2.2 (0.7‐7.5); moderate dysplasia, 15.8 (5.9‐42.2); severe dysplasia, 72.6 (29.8‐176.9); dysplasia not otherwise specified, 22.9 (6.7‐78.0); and carcinoma in situ, 62.5 (24.1‐161.9). Conclusion. In this study, moderate dysplasia, severe dysplasia, and carcinoma in situ were the only histologic lesions associated with a significantly increased risk of developing squamous cell carcinoma of the esophagus within 3.5 years after endoscopy. Increasing grades of dysplasia were associated with increasing risk, but severe dysplasia and carcinoma in situ had similar degrees of risk, findings that suggest a continuous spectrum of esophageal intraepithelial neoplasia, without morphologically distinguishable dysplasia and in situ carcinoma. A longer follow‐up will be necessary to fully evaluate the less severe diagnostic categories, which may take more than 3.5 years to affect the occurrence of squamous cell carcinoma in this high risk population.

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Novel coronavirus disease caused by severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) has become a public health emergency of international concern. This was first noted in Wuhan, Hubei Province, China, and since then has become widespread globally. We report a 71-year-old woman with documented viral shedding (based on reverse transcription-polymerase chain reaction (RT-PCR) testing) of SARS-CoV-2 for 60 days from the onset of symptoms (55 days from her first positive test and 36 days after complete resolution of symptoms). This is to our knowledge the longest duration of viral shedding reported to date. This case demonstrates that viral shedding after COVID-19 diagnosis can be prolonged.

BackgroundAsthma exacerbations represent a significant disease burden and are commonly caused by rhinovirus (RV), which is sensed by Toll-like receptors (TLR) such as TLR7. Some asthmatics have impaired interferon (IFN) responses to RV, but the underlying mechanisms of this clinically relevant observation are poorly understood.ObjectivesTo investigate the importance of intact TLR7 signalling in vivo during RV exacerbation using mouse models of house dust mite (HDM)-induced allergic airways disease exacerbated by a superimposed RV infection.MethodsWild-type and TLR7-deficient (Tlr7−/−) BALB/c mice were intranasally sensitised and challenged with HDM prior to infection with RV1B. In some experiments, mice were administered recombinant IFN or adoptively transferred with plasmacytoid dendritic cells (pDC).ResultsAllergic Tlr7−/− mice displayed impaired IFN release upon RV1B infection, increased virus replication and exaggerated eosinophilic inflammation and airways hyper reactivity. Treatment with exogenous IFN or adoptive transfer of TLR7-competent pDCs blocked these exaggerated inflammatory responses and boosted IFNγ release in the absence of host TLR7 signalling. TLR7 expression in the lungs was suppressed by allergic inflammation and by interleukin (IL)-5-induced eosinophilia in the absence of allergy. Subjects with moderate-to-severe asthma and eosinophilic but not neutrophilic airways inflammation, despite inhaled steroids, showed reduced TLR7 and IFNλ2/3 expression in endobronchial biopsies. Furthermore, TLR7 expression inversely correlated with percentage of sputum eosinophils.ConclusionsThis implicates IL-5-induced airways eosinophilia as a negative regulator of TLR7 expression and antiviral responses, which provides a molecular mechanism underpinning the effect of eosinophil-targeting treatments for the prevention of asthma exacerbations.