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M Coli

Publications and source records attributed to M Coli.

6 recordsLinked to original sources

Normal values of echocardiographic measurements. A population-based study.

OBJECTIVE: To describe echocardiographic measurements and left ventricular mass in a population sample of healthy adults inhabitants of the urban region of Porto Alegre. METHODS: An analytical, observational, population-based, cross-sectional study was done. Through a multi-stage probability sample, 114 individuals were selected to be submitted to a M-mode and two-dimensional echocardiogram with color Doppler. The analyses were restricted to healthy participants. Echocardiographic measurements were described by mean, standard deviation, 95 percentile and 95% confidence limits. RESULTS: A total of 100 healthy participants, with several characteristics similar to those from the original population, had a complete and reliable echocardiographic examination. The measurements of aorta, left atrium, interventricular septum, left ventricle in systole and diastole, left posterior wall and left ventricular mass, adjusted or not for body surface area or height, were significantly higher in males. The right ventricle size was similar among the genders. Several echocardiographic measurements were within standard normal limits. Interventricular septum, left posterior wall and left ventricular mass, adjusted or not for anthropometric measurements, and aortic dimensions had lower mean and range than the reference limits. CONCLUSION: The means and estimates of distribution for the measurements of interventricular septum, left posterior wall and left ventricular mass found in this survey were lower than those indicated by the international literature and accepted as normal limits.

Adult↗

Temperature effects on the structural and functional properties of GPI-anchored and anchor-less bull seminal plasma ecto-5'-nucleotidase.

The effects of temperature on the three-dimensional organization and on the secondary structure of GPI-anchored 5'-nucleotidase from bull seminal plasma and of its anchor-less form (solubilized ecto-5'-nucleotidase), obtained after GPI anchor removal by phosphatidylinositol-specific phospholipase C were investigated in parallel by circular dichroism and fluorescence spectroscopy. The structural features of the two enzymes were correlated to their functional properties in the temperature range of 25-90 degrees C. The kinetic data indicated that the enzyme activities were temperature dependent, showing the maximal values at 60 degrees C. The relevant Arrhenius plots were linear in the temperature range of 20-60 degrees C and the activation energies were 44.4 and 51.8 kJ/mol for the solubilized and GPI-anchored 5'-nucleotidase, respectively. The time-course measurements of enzyme activity, in the temperature range of 25-55 degrees C, revealed that the two enzymes were of different thermal stability, the solubilized ectoenzyme showing lower thermal deactivation constants and longer half lives. Fluorescence and near UV circular dichroism spectroscopy showed that temperature increases induced remarkable changes in the protein tertiary structure of the two enzymes, whereas far-UV circular dichroism analysis revealed only a small temperature effect on the protein secondary structure content.

5'-Nucleotidase↗

Purification of 5'-nucleotidase from human seminal plasma.

5'-Nucleotidase from human seminal plasma was purified to electrophoretic homogeneity and some of its kinetic and molecular properties compared with those of 5'-nucleotidase from bull seminal plasma. The purification of the enzyme was achieved by using the same affinity chromatography media (Con A-Sepharose and AMP-Agarose or ADP-Agarose) previously used for the purification of bull seminal plasma 5'-nucleotidase (Fini, C., Ipata, P.L., Palmerini, C.A. and Floridi, A. (1983) Biochim. Biophys. Acta 748, 405-412). However, in the present purification procedure no detergent was used as it had been necessary for the purification of the bovine enzyme. The experimental data reveal some main differences between these two enzymes; first, the human enzyme seems to be constituted of a single polypeptide chain of about 71 kDa, while the 5'-nucleotidase of bull seminal plasma, in non denaturing detergent solutions, is a homodimer of about 160 kDa. Another most remarkable difference is that the human enzyme does not seem to contain a phosphatidylinositol anchoring system like the one present in the bovine enzyme and in 5'-nucleotidase of different sources (Low, M.G. (1987) Biochem. J. 244, 1-13). Finally, the AMPase activity of 5'-nucleotidase from human seminal plasma is not affected by dithiothreitol which, on the contrary, is a powerful inhibitor of the bovine enzyme causing the dissociation of its subunits which are held together by disulphide bridges (Fini, C., Minelli, A., Camici, M. and Floridi, A. (1985) Biochem. Biophys. Acta 827, 403-409).

5'-Nucleotidase↗

Histology of bronchial carcinoma and regional lymph nodes as putative immune response of the host to the tumor.

Two hundred forty-two patients who had bronchial carcinoma and who underwent radical surgery were studied in order to determine putative host resistance to the tumor at histologic level, i.e., lymphocytic infiltration in the center and around the tumor, together with sinus histiocytosis and follicular hyperplasia in the regional lymph nodes. These features were evaluated in a semiquantitative way, giving rise to three groups of patients: D- (reaction absent or poor), D+ (reaction present), and D++ (strong reaction present). Five-year survival rates and the incidence of metastases in regional nodes were significantly related to the putative host resistance against the tumor, but no clear-cut correlation between grade of malignancy of the tumor and histologic type was evidenced. The significance of these reactive changes is fully discussed.

Adenocarcinoma↗