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INTRODUCTIONSeveral indications to eradicate Helicobacter pylori are now well established. 1, 2 However, the ideal regimens for the treatment of H. pylori infection have not yet been de®ned. The combination of metronidazole/tetracycline/ bismuth or metronidazole/clarithromycin/proton pump inhibitor are currently considered standard regimens for the treatment of H. pylori infection. 3±5 The eradication rates are higher than 80% if the H. pylori strains are sensitive to metronidazole. However, metronidazole resistance is a rising problem world-wide, particularly in developing countries, which limits the usefulness of this drug. 6±9 Furazolidone, a nitrofuran that has been in clinical use for over 30 years, has a favourable safety pro®le and is relatively inexpensive. It was used in China for the treatment of peptic ulcer disease long before H. pylori was discovered as an aetiological agent in this disease. 10,11 In the last decade, furazolidone has been found to be effective in the eradication of H. pylori, 12±14 SUMMARYBackground: A furazolidone-containing therapeutic regimen for Helicobacter pylori infection has attracted special interest in the face of a rising world-wide metronidazole resistant H. pylori, and the expense of currently used antimicrobial regimens. Aim: To evaluate the ef®cacy of furazolidone-containing regimens in eradicating H. pylori. Methods: One-hundred and forty H. pylori positive patients with endoscopically con®rmed duodenal ulcer or functional dyspepsia received one of four different regimens to eradicate H. pylori. In the ®rst trial, the patients were randomly assigned to receive a 1-week course of furazolidone 100 mg b.

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has led to an outbreak of a pandemic worldwide. For better understanding the viral spike (S) protein variations and its potential effects on the interaction with the host immune system and also in vaccine development, the cell epitopes, glycosylation profile and their changes during the global transmission course were characterized and compared with SARS-CoV for their glycosylation profile. We analyzed totally 7,813 sequences screened from 8,897 whole genome sequences on GISAID database up to April 26, and 18 S protein amino acid variations with relatively high frequency (≥10 −3) were identified. A total of 228 sequences of variants had multiple variations, of note, most of them harboring the D614G mutation. Among the predicted 69 linear B cell epitopes, 175 discontinuous B cell epitopes and 41 cytotoxic T lymphocyte epitopes in the viral S protein, we found that the protein structure and its potential function of some sites changed, such as the linear epitope length shortened and discontinuous epitope disappeared of G476S. In addition, we detected 9 predicted N-glycosylation sites and 3 O-glycosylation sites unique to SARS-CoV-2, but no evidently observed variation of the glycan sites so far. Our findings provided an important snapshot of temporal and geographical distributions on SARS-CoV-2 S protein cell epitopes and glycosylation sites, which would be an essential basis for the selection of vaccine candidates.