Abstract: A tetrapeptide having antioxidant activity is provided. The tetrapeptide has a structure comprising, in amino acid sequence from N-terminus to C-terminus: tryptophan-X-tyrosine-X; wherein X is arginine, lysine, histidine or any positively-charged amino acid derivative such as 5-hydroxylysine, ornithine, 2,4-diamino-butyrate and 2,3-diamino-propionate. Each amino acid of the sequence or its Homo-amino acid derivative is independently of the D configuration (D-stereoisomer) or of the L configuration (L-stereoisomer), and the C-terminal comprises one selected from the group consisting of carboxyl (—COOH), and carboxamide (—CONH2). A composition stabilized to oxidation or having antioxidant activity and a method for attenuating effects of free radicals on a keratinous material are also provided.

Abstract: A tetrapeptide having antioxidant activity is provided. The tetrapeptide has a structure comprising, in amino acid sequence from N-terminus to C-terminus: tryptophan-X-tyrosine-X; wherein X is arginine, lysine, histidine or any positively-charged amino acid derivative such as 5-hydroxylysine, ornithine, 2,4-diamino-butyrate and 2,3-diamino-propionate. Each amino acid of the sequence or its Homo-amino acid derivative is independently of the D configuration (D-stereoisomer) or of the L configuration (L-stereoisomer), and the C-terminal comprises one selected from the group consisting of carboxyl (—COOH), and carboxamide (—CONH2). A composition stabilized to oxidation or having antioxidant activity and a method for attenuating effects of free radicals on a keratinous material are also provided.

Abstract: The invention relates to novel polypeptides and to the use thereof for the in vitro assessment of the sensitizing potential of a test compound, to a method for the in vitro assessment of the sensitizing potential of a test compound, to an in vitro method for selecting a compound suitable for reducing the sensitization, as well as to kits for implementing such methods.

Abstract: The invention relates to novel polypeptides and to the use thereof for the in vitro assessment of the sensitising potential of a test compound, to a method for the in vitro assessment of the sensitising potential of a test compound, to an in vitro method for selecting a compound suitable for reducing the sensitisation, as well as to kits for implementing such methods.

Abstract: Derivatives of Maurotoxin (MTX) in which the native disulfide bridge pattern (Cys3-Cys24, Cys9-Cys29, Cys19, Cys31-Cys34) has been disrupted are useful for the treatment of pathologies associated with dysfunctioning and/or activation of Ca2+-activated and/or voltage-gated K+ channel subtypes, such as IKCa1 or Kv1.2. In one group of derivatives, one or two of the amino acid residues of maurotoxin have been replaced by different amino acid residues resulting in the disulfide bridge pattern being changed to Cys3-Cys24, Cys9-Cys29, Cys13-Cys31, Cys19-Cys34. Exemplary substitutions include the Arg residue at position 14 and/or the Lys residue at position 15 replaced by a Gln residue and the Gly residue at position 33 replaced by an Ala residue. Pi1 and HsTx1 derivatives with disrupted native disulfide bridge patterns are similarly useful.

Abstract: OsK1 is a 38-residue peptide with 3 disulphide bridges and is found in the venom of the scorpion Orthochirus scrobiculosus. It is potently active on voltage-gated K+ channels Kv1.1, Kv1.2 and Kv1.3, and moderately active on the type 1 intermediate-conductance Cat2+-activated channel KCa3.1. Derivatives of OsK1, particularly involving truncation or point mutations, have been developed to enhance the activity against and selectivity for the Kv1.3 channel. This renders the derivatives likely candidates for the treatment of autoimmune diseases, including multiple sclerosis. Such use may be alone or in combination therapy with maurotoxin, another scorpion toxin.

Abstract: Derivatives of Maurotoxin (MTX) in which the native disulfide bridge pattern (Cys3-Cys24, Cys9-Cys29, Cys19, Cys31-Cys34) has been disrupted are useful for the treatment of pathologies associated with dysfunctioning and/or activation of Ca2+-activated and/or voltage-gated K+ channel subtypes, such as IKCa1 or Kv1.2. One preferred group of derivatives is that in which one or more of the Cys residues have been replaced with ?-aminobutyrate (Abu) residues, thus breaking one or more of the four disulphide bridges. Within this group, the preferred derivative is that in which the Cys residues at position 9, 19, 29 and 34 have been replaced with a ?-aminobutyrate residues.

Abstract: Maurocalcine, a novel toxin isolated from the venom of the Tunisian chactidae scorpion Scorpio maurus palmatus, has the amino acid sequence GDCLPHLKLCKENKDCCSKKCKRRGTNIEKRCR (SEQ. ID. No. 1). It potently and reversibly modifies channel gating behaviour of type 1 ryanodine receptor (RyR1) by inducing prominent subconductance behavior. Maurocalcine and its bioactive structural analogues—preferably those containing the KKCKRR motif corresponding to part of the II-III loop of the alpha1S subunit of the voltage-dependent skeletal muscle calcium channel dihydropyridine receptor—appear to possess a therapeutic potential, notably as candidate immuno-suppressive drugs, and for the treatment of pathologies in humans that may involve a dysfunction of calcium channels.

Abstract: Multiple branch peptide constructions formed from peptide-branches derived from the envelope transmembrane glycoprotein gp41 of HIV, and including the consensus sequence RQGY preceded by 0 to 4 amino acid residues and succeeded by 0 to 4 amino acid residues, most preferably RQGYS, show increased receptor affinity and prevent cell-to-cell fusion. They have a direct virostatic effect. Because they present the same peptide sequence several times, these MBPCs are able to neutralize in vitro the different steps of virus envelope/cell membrane fusion, and infected cell membrane/uninfected cell membrane fusion of several strains of HIV-1 and HIV-2. These results open a potential use in treatment of HIV infection.

Abstract: The folding/oxidation of a reduced peptide or partially reduced peptide to form a disulphide bridged peptide is effected by dissolving it in an oxidizing organic solvent, alone or in admixture with water, adding an aqueous alkaline buffer to the solution, and recovering the resultant disulphide bridged peptide. The preferred oxidizing organic solvent is dimethylsulphoxide, which is desirably used as a 10 to 50% aqueous solution. The addition of the aqueous alkaline buffer, which is preferably a 0.2 M Tris-HCI buffer, is preferably added during a period of from 5 to 90 minutes after dissolution of the reduced peptide in the oxidizing organic solvent. The method allows reduced peptides which are insoluble in alkaline conditions to be oxidized and allows reduced peptides which may form stable but inactive oxidized species if treated with dimethylsulphoxide alone to be fully oxidized.

Abstract: The activity and cell membrane affinity of certain antiviral multiple branch peptide constructions, including those known from WO 95/07929, WO 98/29443 and WO 03/95479, can be improved by bonding to the C-end of the peptide a terminator which is either (a) an ?-amino-fatty acid having from 4 to 10 carbon atoms and from 0 to 2 carbon-carbon double bonds or (b) a peptidic cell membrane penetrating agent. The improvement is so marked that in some cases the number of branches can be reduced, sometimes to a single branch, and/or that the branches may be shortened. The preferred ?-amino-fatty acids are ?-aminobutyric acid, ?-aminovaleric acid and ?-aminocaproic acid. The peptidic cell membrane penetrating agent is suitably a TAT-derived peptide, penetratin® or Kpam.

Abstract: Multiple branch peptide constructions formed from peptide-branches derived from the envelope transmembrane glycoprotein gp41 of HIV, and including the consensus sequence RQGY preceded by 0 to 4 amino acid residues and succeeded by 0 to 4 amino acid residues, most preferably RQGYS, show increased receptor affinity and prevent cell-to-cell fusion. They have a direct virostatic effect. Because they present the same peptide sequence several times, these MBPCs are able to neutralize in vitro the different steps of virus envelope/cell membrane fusion, and infected cell membrane/uninfected cell membrane fusion of several strains of HIV-1 and HIV-2. These results open a potential use in treatment of HIV infection.

Abstract: A subject of the present invention is the use of peptide fragments of the ?-1 sub-unit of the calcium channels of mammals, of sequences derived by mutation of said fragments, or also of cells transformed by sequences coding for said fragment or derived sequences, for screening of molecules of therapeutic interest.

Abstract: Derivatives of Maurotoxin (MTX) in which the native disulfide bridge pattern (Cys3-Cys24, Cys9-Cys29, Cys19, Cys31-Cys34) has been disrupted are useful for the treatment of pathologies associated with dysfunctioning and/or activation of Ca2+-activated and/or voltage-gated K+ channel subtypes, such as IKCa1 or Kv1.2. One preferred group of derivatives is that in which one or more of the Cys residues have been replaced with ?-aminobutyrate (Abu) residues, thus breaking one or more of the four disulphide bridges. Within this group, the preferred derivative is that in which the Cys residues at position 9, 19, 29 and 34 have been replaced with a ?-aminobutyrate residues.

Abstract: Maurocalcine, a novel toxin isolated from the venom of the Tunisian chactidae scorpion Scorpio maurus palmatus, has the amino acid sequence GDCLPHLKLCKENKDCCSKKCKRRGTNIEKRCR (SEQ. ID. No. 1). It potently and reversibly modifies channel gating behaviour of type 1 ryanodine receptor (RyR1) by inducing prominent subconductance behavior. Maurocalcine and its bioactive structural analogues—preferably those containing the KKCKRR motif corresponding to part of the II-III loop of the alpha1S subunit of the voltage-dependent skeletal muscle calcium channel dihydropyridine receptor—appear to possess a therapeutic potential, notably as candidate immuno-suppressive drugs, and for the treatment of pathologies in humans that may involve a dysfunction of calcium channels.

Abstract: Multiple branch peptide constructions formed from peptides derived from the envelope transmembrane glycoprotein gp41 of HIV, and including the consensus sequence RQGY preceded by 0 to 4 amino acid residues and succeeded by 2 to 4 amino acid residues, most preferably RQGYSPL, show increased receptor affinity and prevent cell-to-cell fusion. They have a direct virostatic effect. Because they present the same peptide sequence several times, these MBPCs are able to neutralize in vitro the different steps of virus envelope/cell membrane fusion, and infected cell membrane/uninfected cell membrane fusion of several strains of HIV-1 and HIV-2. These results open a potential use in treatment of HIV infection.

Abstract: Polypeptides encoded by the nef gene of Human Immunodeficiency Virus (HIV), which is the major etiological agent of Acquired Immune Deficiency Syndrome (AIDS), are identified. The polypeptides, a diagnostic method for detecting antibodies to HIV in biological fluids, a diagnostic kit for carrying out the method, and pharmaceutical compositions containing the polypeptides are described. The polypeptides are useful in viral vaccines and for the early detection of HIV infection in humans.