Abstract: A transmission buffer of a signal transmission device according to the embodiment includes: a differential circuit portion that is connected between the first potential and the second potential; a variable current source portion that supplies current to the differential circuit portion; a switch port that switches between a conductive state and a disconnected state between the first transmission terminal and the fixed potential and between the second transmission terminal and the fixed potential; and a controller that controls the current supplied by the variable current source portion to the differential circuit portion, and that controls the operation of the switch portion.

Abstract: The present invention provides peptides represented by the following formula (A): wherein Q represents a physiologically active peptide moiety; X each represents the same or different ?-amino acid residue; M represents Gly or Cys; m represents an integer of from 5 to 8; and n represents an integer of from 0 to 3, or their pharmaceutically acceptable salts thereof. The peptides of the present invention have higher stability and/or higher activity than physiologically active linear peptides to which no cyclic peptide is bonded.

Abstract: The invention relates to an endothelin antagonistic peptide of the formula (I): X-A-Trp-B-Gly-Thr-E-G-Y   (I) SEQ ID NO: 2 wherein represents Asn or Asp; B represents His or Lys; E represents Ala or Ser; G represents Ala or Pro; X represents X1-Gly or  and Y represents hydroxy, lower alkoxy, amino, wherein X1, X3, Y1, Y2 and Z are further defined, or a pharmaceutically acceptable salt thereof.

Abstract: Disclosed in a peptide represented by the following formula (I):

Abstract: The invention relates to biologically pure cultures of Streptomyces sp. RE-701 (FERM BP-3624) and Streptomyces sp. RE-629 (FERM BP-4126) that produce endothelin antagonistic peptides.

Abstract: Peptides represented by the following formula (I): ##STR1## wherein A represents Asn or Asp; B represents His or Lys; and E represents Ala or Ser;(1) X.sup.1 and Y.sup.1 are combined together to form a single bond as X.sup.1 --Y1, or (2) X.sup.1 represents hydrogen and Y.sup.1 represents hydroxy;and Z represents, in case of (1),Trp-Phe-Phe-Asn-Tyr-Tyr-7Hyt-Z.sup.1Trp-Val-Tyr-Phe-Ala-His-Leu-Asp-Ile-Ile-Trp-Z.sup.1,Trp-Val-Tyr-Tyr-Ala-His-Leu-Asp-Ile-Ile-Trp-Z.sup.1,Trp-Leu-Tyr-Phe-Ala-His-Gln-Asp-Val-Ile-Trp-Z.sup.1,Trp-Phe-Phe-Asn-Tyr-R-T-Z.sup.1wherein Z.sup.1 is an organic moiety,wherein R is Tyr or a covalent bond,T is Trp, Ala, Phe, Tyr, Trp-Trp, Asn-Tyr-Tyr-Trp, Trp-Asn-Tyr-Tyr-Trp, Trp-Val-Tyr-Phe-Ala-His-Leu-Asp-Ile-Ile-Trp,or in case of (2), Z representsTrp-Val-Tyr-Phe-Ala-His-Leu-Asp-Ile-Ile-Trp-Z.sup.1Trp-Val-Tyr-Tyr-Ala-His-Leu-Asp-Ile-Ile-Trp-Z.sup.1Trp-Leu-Tyr-Phe-Ala-His-Gln-Asp-Val-Ile-Trp-Z.sup.1.

Abstract: Novel DC-89 compounds represented by the general formula: ##STR1## wherein X represents a single bond or --CH.sub.2 --; and when X represents a single bond, Y represents --CH.sub.2 Br or --CH.sub.2 Cl and when X represents --CH.sub.2 --, Y represents Br, are obtained by the present invention. The compounds have antibacterial and anti-tumor activity.