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Latex from Caricaceae has been known since 1925 to contain strong lipase activity. However, attempts to purify and identify the enzyme were not successful, mainly because of the lack of solubility of the enzyme. Here, we describe the characterization of lipase activity of the latex of Vasconcellea heilbornii and the identification of a putative homologous lipase from Carica papaya. Triacylglycerol lipase activity was enriched 74-fold from crude latex of Vasconcellea heilbornii to a specific activity (SA) of 57 μmol·min−1·mg−1 on long-chain triacylglycerol (olive oil). The extract was also active on trioctanoin (SA = 655 μmol·min−1·mg−1), tributyrin (SA = 1107 μmol·min−1·mg−1) and phosphatidylcholine (SA = 923 μmol·min−1·mg−1). The optimum pH ranged from 8.0 to 9.0. The protein content of the insoluble fraction of latex was analyzed by electrophoresis followed by mass spectrometry, and 28 different proteins were identified. The protein fraction was incubated with the lipase inhibitor [14C]tetrahydrolipstatin, and a 45 kDa protein radiolabeled by the inhibitor was identified as being a putative lipase. A C. papaya cDNA encoding a 55 kDa protein was further cloned, and its deduced sequence had 83.7% similarity with peptides from the 45 kDa protein, with a coverage of 25.6%. The protein encoded by this cDNA had 35% sequence identity and 51% similarity to castor bean acid lipase, suggesting that it is the lipase responsible for the important lipolytic activities detected in papaya latex.

SUMMARY obfective We wished to assess the predictive value of the main clinical risk factors for osteoporosis over a low vertebral bone mineral density design A cross-sectional study was made of a cohort of peri and post-menopausal women (mean age, 54 years) patients One thousand, five hundred and sixty-five normal white women were selected from among the women referred to our menopause clinic for screening and prevention of osteoporosis measurements Each woman had replied to a detailed standardized questionnaire including the main clinical risk factors and had her bone density measured using dual photon absorptiometry results The predictive value for a low vertebral bone mineral density (2 SD below the normal young adult value) was assessed for 15 historical and anthropometric vari-ables. Among these, age, age at menarche, weight, height, menopause and its duration, were independant predictors of a low bone mineral density, in a multiple logistic regression analysis. Odds ratios were calculated for each of these variables, weight, menopause and its duration being the three most influential variables. At best this model makes it possible to correctly classify 73% of women with a low bone mineral density and 66% of those with a normal bone mineral density. If this model Is used for screening, it could possibly save 25% of bone denslto-metry examinations conclusions Direct bone densitometry remains indispensable to assess osteoporosis risk, since risk factors alone are not sufficient for accurate delineation of either low or normal bone mineral density

Model choice techniques are proposed for logistic regression, based on prediction criterion estimation similar to Akaike's information criterion. For artificial insemination data of cattle, we wish to study a factor influence on success proportion; tests standard methods don't always seem suitable for prediction objective. Two prediction criterion estimate methods are applied to these data: simulated bootstrap and asymptotic estimates. Some empirical properties of this estimate are studied.