Gamma trypsin: purification and physicochemical characterization of a novel bovine trypsin isoform.

A novel bovine trypsin isoform was purified from commercial sample by ion exchange chromatography by Sephadex SP C50®. New isoform contains in addition of loss of N-terminus hexapeptide (as found in parent molecule β-trypsin) an intra-chain split between Lys-155 and Ser-156. The novel enzyme denominate γ-trypsin showed similar properties with α-trypsin isoform in polypeptide number chain (two chain), molecular masses (23,312 Da), secondary structure, hydrodynamic radius and others.

Molecular dynamics and circular dichroism studies of human and rat C-peptides.

Proinsulin C-peptide has been recently described as an endogenous peptide hormone, responsible for important physiological functions others than its role in proinsulin processing. Accumulating evidences that C-peptide exerts beneficial effects in the treatment of long term complications of patients with type 1 diabetes mellitus indicate that this molecule may be administered together with insulin in future therapies. Despite its clear pharmacological interest, the secondary and three-dimensional (3D) structures of human C-peptide are still points of controversy.

Detection and characterization of leishmania antigens from an American cutaneous leishmaniasis vaccine for diagnosis of visceral leishmaniasis.

Antigens were isolated from vaccines against American Cutaneous Leishmaniasis (ACL) and their reactivity tested against nine different groups of human sera and two groups of dog sera. These antigens react specifically with human and dog visceral leishmaniasis sera when compared to sera from non-infected individuals. Sera from humans from endemic areas of ACL before, or one year after, vaccination, and ACL patients treated and cured by immunotherapy with polyvalent vaccine, did not display significant differences of reactivity to these antigens.

Leishmania major-like antigen for specific and sensitive serodiagnosis of human and canine visceral leishmaniasis.

An antigen (LMS) prepared from Leishmania major-like promastigotes was used in an enzyme-linked immunosorbent assay (ELISA) for the diagnosis of human and dog visceral leishmaniasis. The results were compared with those from the indirect immunofluorescent antibody test (IFAT). A total of 1822 canine sera were tested, including sera from dogs with visceral leishmaniasis, transmissible venereal tumors, ehrlichiosis, rickettsiosis, or Chagas' disease and sera from healthy dogs.