Amendments: In Association with Its Submission of an Amendment of Tender Offer Statement, Shionogi Announces: (1) Partial Amendment of Its Press Release Entitled “Shionogi Announces Commencement of Tender Offer for Certificates of Shares, Etc. in UMN Pharma Inc. (Securities Code: 4585)” and (2) Amendment of Its Corresponding Public Announcement of Commencement of Tender Offer, and Corrections