ABSTRACT
Isolation of proteinase inhibitors from the sea anemone Stichodactyla helianthus was achieved by trichloroacetic acid treatment of the aqueous extract followed by affinity chromatography on trypsin-Sepharose and ion-exchange chromatography on CM-cellulose. The average molecular mass of the major inhibitor (ShPI-I) obtained by fast atom bombardment mass spectrometry (FAB-MS) was 6110.6 Da. The amino acid sequence was determined by FAB-MS combined with manual Edman degradation, digestions with endopeptidases and exopeptidases and automatic sequencing. The sequence of ShPI-I (55 amino acids) was compared with those reported in the SwissProt database for several proteinase inhibitors and significant similarity to inhibitors belonging to the Kunitz family was observed. ShPI-I exhibits a broad specificity for serine, cysteine and aspartic proteinases. The dissociation constants of the complexes formed with different enzymes were determined. The affinity-purified fraction (PI) was immobilized on Sepharose and used in the purification of different classes of proteinases.
Subject(s)
Enzymes, Immobilized/chemistry , Enzymes, Immobilized/isolation & purification , Protease Inhibitors/chemistry , Protease Inhibitors/isolation & purification , Sea Anemones/enzymology , Amino Acid Sequence , Animals , Chromatography, Agarose , Enzymes, Immobilized/metabolism , Molecular Sequence Data , Protease Inhibitors/metabolism , Sea Anemones/chemistry , Sea Anemones/metabolism , Trypsin Inhibitor, Kunitz Soybean/chemistry , Trypsin Inhibitor, Kunitz Soybean/isolation & purification , Trypsin Inhibitor, Kunitz Soybean/metabolismABSTRACT
OBJECTIVE: To assess the knowledge and skills of general practitioners in Quebec with respect to persons with dementia. DESIGN: A questionnaire containing 47 multiple-choice questions on aptitude and nine questions on practice profiles and demographics. SETTING: Province of Quebec. PARTICIPANTS: Twelve hundred general practitioners selected randomly. MAIN OUTCOME MEASURES: Performance with respect to the questionnaire's four objectives: to rate background knowledge, to evaluate physicians' knowledge of the assessment and treatment of dementia, to assess follow-up, and to assess interpersonal skills. RESULTS: Average performance on the questionnaire was 64.7%, with a standard deviation of 11.79%. Performance did not differ markedly from one objective to the next. Most respondents were male (61.6%), working in urban settings (61.7%). Most (72.5%) were between 25 and 44 years, and 44.7% had between 6 and 15 years' experience. About half (44.7%) belonged to group practices, 43.8% worked in acute care hospitals, and 20.6% worked in extended care hospitals. CONCLUSIONS: Quebec general practitioners have average ability to care for patients with dementia. Continuing education should focus on increasing physicians' knowledge of dementia, especially for those with the lowest scores; physicians 55 years and older, those practising alone, and those who spend less than 60% of their practice time with elderly patients.