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P Magnin

Publications and source records attributed to P Magnin.

At least 37 records · Page 2Linked to original sources
PubMed1987

Oxidation-reduction potential studies: a new method in pharmacology principles, materials, and methods.

Oxidation-reduction (redox) potential measurement is not used in pharmacology at the present time. However, it represents a physicochemical parameter that may be as important as the other currently used physicochemical parameters, such as pH and pKa. Redox potential variations include conformational modifications that may influence bioavailability of drugs. We report here an original and convenient equilibrium method to determine this potential in biological fluids, especially in blood.

Female↗
PubMed1987

[Platelet antioxidant enzyme activities in arteriopathy].

Some publications have pointed out that oxygen free radicals can induce injury of vessel wall and increase platelet aggregation and clotting, which can suppose a dependent relationship with arteriosclerotic process. We therefore studied the hypothesis of a possible abnormal platelet antioxidant enzymatic equipment in arteriopathic patients. A control group of 20 healthy subjects and an other one of 40 non diabetic patients with peripheral arterial disease were investigated, and the following tests were performed: measure of transcutaneous oxygen tension (PTCO2), determination of activity of platelet superoxide dismutase (SOD), glutathione-peroxidase (G-Px) and catalase (CAT). A significant decrease of SOD and G-Px is observed in platelets of arteriopathic patients. This decrease seems to be correlated with the severity of ischemia. The pathological reduction of platelet antioxidant equipment can be one factor enhancing thrombotic complications in chronic arterial disease.

Arteritis↗
PubMed1985

[HDL cholesterol and physical training: comparative study of a group of sedentary with a group of athletic young subjects].

Many recent studies have clearly established the anti-atherogenic effect of serum HDL cholesterol. Serum HDL cholesterol was quantified in sedentary young people (less than two weekly hours of moderate physical exercise) and in active young people (average five weekly hours of intense physical exercise). A statistical comparative study indicates that this physical training difference goes with significantly higher HDL cholesterolemia in active young people.

Adult↗
PubMed1985

[Analytical interference of lipid parenteral feeding with the determination of methemoglobin levels by an autoanalyzer].

We report here an unusual cause of analytical interference observed in methemoglobin values of patients parenterally given nutritive lipid emulsions. In these patients, harboured in intensive care department, T Hb, % O2 Hb, % COHb, Met Hb values are systematically measured using IL 282 CO-Oximeter autoanalyser in addition to daily blood gas determination (pH, PaCO2, PaO2). An increase in % Met Hb rate up to 10-20% was observed in lipid emulsions receiving patients. We first verified that washing red blood cells with saline instantaneously lowers Met Hb values to less than 1%. The mechanism of this interference was addressed by performing three Met Hb determination methods in normal blood in vitro added with variable amounts of lipid emulsions: CO-Oximeter determination, classical Evelyn Malloy method, analysis of continuous absorption spectra between 480 and 640 nm. Results corroborate the spectral origin of the analytical interference observed with CO-Oximeter and leading to false positive values. Blood lipids increase unspecifically the wave length proportional absorption between 480 and 640 nm. Evelyn Malloy's technique suppresses this interference since it uses the ratio of differences in optical densities. Our results emphasize the necessity of knowing patients therapeutics when performing laboratory investigations.

Autoanalysis↗
PubMed1984

[Is it legitimate today to perform large rotations with forceps?].

Many authors argue against the practice of large forceps rotations on the basis of a threefold increased neonatal risk compared to the use of forceps for anterior presentations. The experience of the Obstetric Clinic of Hôpital Edouard-Herriot in Lyon, of 81 major forceps rotations from a series of more than 10 000 births, is very similar to that of Chiswick in Manchester, based on 86 cases. In nearly one quarter of the neonates, there are discreet, transient neurological signs which disappear within one week and, did not leave any permanent sequelae. It would appear that large rotations should not be totally forbidden, but that their indications have to be carefully considered, especially in cases of foetal distress. An experienced obstetrician can perform these rotations: in experienced hands, they are often straightforward, but in cases of unexpected difficulty (1 case in 10 or 20) it should be immediately abandoned and a caesarian should be performed.

Apgar Score↗
PubMed1982

Low field topical nuclear magnetism apparatus in a hospital area.

We describe the technique and the measure of the relaxation time T2 for the free precession of protons in the earth field. In vitro and in vivo experiments on human physiological fluids, including blood coagulation, are reported. We put forward the evident interest of this technique to study the meconium in the amniotic liquid and small quantities of oscite observed in situ.

Amniotic Fluid↗
PubMed1982

Estimating meconium (fetal feces) concentration in human amniotic fluid by nuclear magnetic resonance.

Measurements are reported of NMR relaxation times (T2) on hydrogen in water of isotonic NaCl solutions and of normal human amniotic fluid in which known concentrations of meconium (fetal feces) were dissolved. Magnetic fields for resonance of 23.5 X 10(3) and 0.6 oersteds were used. From the measured T2 values, reliable estimates of meconium concentrations could be obtained that might be considered estimates of fetal distress. Observed minor variation of T2 values was probably due to the mucopolysaccharides comprising 80% of the meconium weight. Advantages of this technique for possible clinical use in obstetrics include small volume of sample required (0.1 ml), lack of necessity for sample filtration or centrifugation, and shortness of time required for analysis (less than 30 min).

Amniotic Fluid↗
PubMed1981

[Steady state ergometry: fact or fiction].

The steady state is a physiological condition whereby the metabolic requirements are met and the criteria parameters are stable. Four groups of male subjects were evaluated on their VO2 for a one hour duration ergocycle effort at 75%, 50%, 25% and 10% of their maximum individual VO2. Three cardio-respiratory parameters (heart frequency, oxygen consumption, pulmonary ventilation) and one biochemical parameter (lactic acid) were measured The evolution of the control parameters during the task were completed according to the requirements of the literature. For the long-duration efforts (one hour) we notice the absence of a steady-state for the cardio-respiratory parameter. We cannot however rule-out the existence of a steady state for the biochemical parameter for the lighter efforts of 10% and 25% of the VO2 maximum.

Adult↗
PubMed1981

[The risk of thrombo-embolism in pregnancy and in the post-partum period. A review of 28,828 pregnancies (author's transl)].

Looking through a retrospective study of 28,828 deliveries the authors have been able to work out the frequency of thrombo-embolic complications of pregnancy (1 per 1000) and of the post-partum (3.95 per 1000). It is possible to point to different risk factors. Some are well known, these are varicose veins, Caesarean section, maternal age above 35. Other factors that are usually considered to be aetiological now appear to be less significant. These are: a history of previous thrombo-embolic conditions and post-partum sterilization. To be added to the classic risk factors are inhibition of lactation which, whatever procedure is used, significantly raises the incidence of thrombo-embolic complications. It would seem to be desirable, in view of these different parameters, that a risk score should be drawn up which would allow for medical treatment to be given prophylactically in the patients who are particularly exposed to risk.

Age Factors↗
PubMed1980

[Prognostic value of vesperal or nocturnal rises in blood pressure during toxaemia of pregnancy. 58 cases (author's transl)].

In a study of 58 cases of toxaemia of pregnancy, the authors found foetal suffering to be present in 14 out of 21 women who showed sudden vesperal or nocturnal rises in BP, as against 5 out 37 other women. Such rises in BP seem to be of worse prognostic value than mere hypertension or hyperuricaemia. When they are superimposed on one or the other of these conditions, foetal suffering is almost the rule. Variations in BP values throughout the night and day should be taken into account when planning therapeutic measures, notably induced delivery.

Blood Pressure↗