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Biomedical subjects

A Frigola

Publications and source records attributed to A Frigola.

9 recordsLinked to original sources

Determination of ascorbic and dehydroascorbic acids in blood plasma and serum by liquid chromatography.

A liquid-chromatography (LC) method with ultraviolet detection for measuring ascorbic (AA) and dehydroascorbic acid (DHA) in human blood and serum was studied. The method used an ODS reversed-phase column and cetyltrimethyl ammonium bromide as an ion-pairing agent. AA was measured before and after the reduction of DHA with dithiothreitol. The absence of interferences resulting from hemolysis products was verified and also the stability of the ascorbic acid in metaphosphoric acid extracts. The analytical parameters, linearity (1-80 micrograms/ml), accuracy (recovery, 96.7-100.7%) and precision (C.V. = 3.1%), show that the method is reliable and adequate for measuring the total vitamin C content in serum and plasma.

Ascorbic Acid↗

[Acute lipoid pneumonia. Report of 2 cases].

Lipoid pneumonia is a chronic infiltrative pulmonary process secondary to continued aspiration of exogenous lipids (laxatives and nasal drops). On occasions, an acute form of lipoid pneumonia which may lead to respiratory failure may be observed coinciding with accidental massive aspirations of lipidic material. Two cases of acute lipoid pneumonia secondary to paraffin aspiration in << fire eaters >> are presented.

Accidents, Occupational↗

Determination of Cd, Cu, Pb and Zn content of infant formulas by differential pulse anodic stripping voltammetry (DPASV).

The differential pulse anodic stripping voltammetry (DPASV) method described is based on the one reported by Hasse et al., but adapted to normal laboratory conditions. The values obtained in the estimation of the analytical parameters (linearity, detection and quantification limits, precision and accuracy) show that in the conditions described the method is sensitive enough, reliable and useful for determining these elements in infant formulas. A comparison between DPASV and atomic absorption spectroscopy (AAS) methods in the conditions described here shows that the former is less sensitive but that they are similar in precision. The cadmium, copper, lead and zinc contents of different types of infant formulas marketed in Spain are reported.

Electrochemistry↗

Determination of antithrombin activity by an amidolytic and a clotting procedure.

Plasma antithrombin activity was measured using an amidolytic method (substrate Chromozym TH) and a clotting method. The mean antithrombin values found in 76 hospital outpatients were 9.4 micronmol/min/ml with the amidolytic procedure and 100.1% of antithrombin activity with the clotting procedure. The two methods correlate fairly well (r = 0.85, P less than 0.01) and show satisfactory reproducibility. Coefficients of variation of 5.9% and 8.8% were obtained respectively with the amidolytic and the clotting procedures. In the presence of very high levels of fibrinogen degradation products, falsely elevated antithrombin activity levels were observed with the clotting procedure but the amidolytic method is essentially unaffected. It is concluded that both methods are suitable for determining antithrombin activity but a well-standardised amidolytic procedure has advantages.

Aniline Compounds↗

Standardisation of a simple method for the determination of antithrombin activity.

A procedure is described for performing a functional assay of serum antithrombin activity. The method consists of adding serum to a thrombin solution and measuring, after a fixed incubation time, the residual thrombin activity on a substrate plasma. The mean serum antithrombin activity found in 96 healthy blood donors using this procedure was 109.5% (range 82%-160%). The method was linear over an activity range between 30.5% and 176%, was significantly correlated with antithrombin-III protein concentration determined by radial immunodiffusion (r = 0.86, P less than 0.01), and showed good reproducibility (coefficient of variation 2.7%). On account of its simplicity and precision this functional assay should be of considerable use in evaluating hypercoagulability.

Adult↗

New method for determining thrombin-clottable fibrinogen.

We describe a new method for determination of thrombin-clottable fibrinogen, which eliminates the systematic error caused by occlusion of other serum proteins in the fibrin clot and reduces the sensitivity to high concentrations of fibrin degradation products. Essentially, the method consists of densitometric quantitation of the fibrin band after a standard electrophoresis run of plasma, thrombin fixation of the fibrinogen, and removal of the non-clotted proteins by washing in saline. The procedure shows good precision and gives results that are accurate, significantly correlate with results for the classical thrombin clotting method (r = 0.92, P less than .001), and are not affected by fibrin degradation product concentrations up to 900 mg/liter. These characteristics make the method especially valuable in establishing fibrogen concentration in patients who are undergoing thrombolytic therapy.

Blood Protein Electrophoresis↗

Viral expression, oncogenicity, and antigenicity of a mouse salivary gland tumor and two cell lines derived from it.

An in vitro cell line (SGT) derived from a mouse submaxillary gland adenocarcinoma (TGS) containing A and B viral particles maintained its oncogenicity only for newborn isogeneic hosts (C3H/He mice) immunosuppressed with antithymocyte serum. Inoculation into adult isogeneic animals did not cause tumor but provided partial protection against a challenge with TGS cells. The loss of oncogenicity for nonimmunosuppressed isogeneic hosts was accompanied by the acqusition of oncogenicity for adult, nonimmunosuppressed, xenogeneic hosts (golden hamsters) given subcutaneous inoculations of SGT cells on the back. From the tumor grown in the hamster, which is histologically similar to the original tumor of the mouse, an in vitro cell line (HWS) was derived. The comparative analysis of the 2 cell lines, SGT and HWS, led to the following conclusions: (a) the karyological pattern of the 2 cell lines in virtually the same; (b) the cell surface antigenic pattern is similar for the 2 cell lines, as determined by colony inhibition test and cytotoxicty test; (c) the cells of the HWS line behave serologically as a mouse-hamster hybrid, also as determined by colony inhibition and cytotoxicity tests; (d) both cell lines have only intracytoplasmic viral particles of the A type; and (e) agglutination with the plant lectins concanavalin A and wheat germ agglutinin occurs at lower concentrations of agglutinin for HWS cells than for SGT cells.

Adenocarcinoma↗