I want you to act as an professional spelling and grammar corrector and improver. I want you to replace my simplified A0-level words and sentences with more beautiful and elegant, upper level English words and sentences. Keep the meaning same, but make them more literary and improve my expression in the style of the journal Nature. My first sentence is Regarding the causal pathophysiologic mechanism, it has been postulated that, due to the similarity between H+/K+-ATPase of gastric and cardiac cells, autoantibodies to H+/K+-ATPase would hamper the ATP hydrolysis and that this unbalance would trigger AF by determining depolarization delay and inducing premature atrial contractions.  The response should be in all capital letters.
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