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Primary cultures of beating myocardial cells of neonatal rat are taken in order to observe the ultrastructural modifications caused by certain long chain fatty acids (erucic acid C22 : 1 and palmitic acid C16 : 0). Reference cultures are established and observed at the same time as the others. The eurcic acid create an intense steatosis, on the opposite palmitic acid does not. On the contrary the transormations of certain cellular organites such as mitochondria, dictyosomes, rough endoplasmic reticulum and ribosomes are observed in both cases.

The need for knowledge concerning foetal pulmonary maturity has led biochemists to develop a number of techniques based upon knowledge of amniotic phospholipids. Study of these phospholipids of foetal pulmonary origin is possible using biochemical and physical methods. The former include the L/S (Lecithin/sphingomyelins) ratio, as well as the measurement of total lecithins, or the palmitic acid/stearic acid ratio (P/S). Physical methods are based upon surface tension (Clements test) or fluidity (measurement of microviscosity by polarization of fluorescence) properties of phospholipids. Combination of several reproducible, sensitive and reliable tests (E/S ratio, microviscosity, Clements test) provides adequate information concerning foetal pulmonary maturity.

The combination VICRYL and bone wax is studied as filling material in periodontal locations in dogs. Histological studies were carried out at one, two, six and nine months. Bone formation is already quite marked at two months, and total at six months. A desmodont and a secondary cement are formed. At six and nine month, reattachment is excellent.

Two parameters have been used to estimate the foetal pulmonary maturity: Clements' test or bubble test and palmitic acid/stearic acid ration. The reliability and the limits of these tests have been studied in function of several pathological pregnancies and the gestations's age. A value greater than 5 for the P/S ratio was a good pronostic at any gestational age. A value lesser than 5 should be examined according to this gestational age. A negative Clements' test has to be confirmed by an another amniocentesis, while a positive test have been followed always by a mature newborn's birth.

Compared to its lean litter mate (Fa/--) the Zucker rat (fa/fa) develops obesity without hyperphagia in the first week of lite. It is characterized by adipocyte hypertrophy and higher lipid content in adipose tissue. In vitro utilization as well as in vitro oxidation by diaphragm of palmitic acid was decreased in 1 week old Zucker rat.

Because of their structures, phleic acids (general formula: CH3-(CH2)m-(CH=CH-CH2-CH2)n-CO2H; main component: m = 14, n = 5) cannot be synthesized by the same kinds of enzymatic systems as other natural polyunsaturated fatty acids. By using specifically labelled 14C compounds, we have tested the ability of different molecules to be incorporated in the phleate skeletons by Mycobacterium phlei. The localisation of radioactive carbon atoms has been studied by chemical degradation of labelled phleates, isolation and purification of the degradation products, and determination of their specific radioactivity. When M. phlei cells are incubated with labelled acetate, the unsaturated and saturated parts of the molecules of phleic acids are unequally labelled. The radioactivity of succinate monoester on the one hand and fatty acids (mixture of myristic and palmitic acids) on the other hand, measured after oxidative degradation of phleate esters, shows a constant ratio under definite conditions. Whether [1-14C]acetate or [2-14C]acetate is used for incubation, the same ratio is observed. Therefore acetate is the precursor of the unsaturated part as well as of the saturated part of the phleate molecules. By using labelled fatty acid esters, it has been found that palmitic acid is the precursor of phleates with m = 14, while myristic acid is the precursor of phleates with m = 12. Stearic and eicosanoic acids are not incorporated without degradation. The hypothesis of a condensation of a saturated fatty acid with a preformed polyunsaturated molecule was examined. Search for such a molecule in the lipids of M. phlei gives negative results. Pentaunsaturated phleate arising from palmitate is more abundant than pentaunsaturated phleate arising from myristate, while the reverse is true for hexaunsaturated phleates. These observations make very unlikely such an hypothesis. An elongation process fits well with the observed facts provided that this process involves elongation by two acetate units simultaneously, making elongation by four carbon atoms at a time. Such a requirement would be easily satisfied if two molecules of acetate are condensed together before their utilization in the elongation process. In such a hypothetical process, crotonate would be the most probable substrate of the elongation reaction.

The ultrastructure and lipid composition of chloroplasts, isolated from various shade and sun plants, were compared. Depending on the origin of the plastid, significant differences were observed in the percentage of appressed thylakoids. Accordingly, plastids could be classified into three different types: Type I chloroplasts, from mesophyll cells of sun plants (barley, corn, spinach, bean), display well-developed grana and intergrana thylakoid membranes. Type II chloroplasts, typical of shade plant (Arum), show giant grana stacks with few interconnecting thylakoids. Type III chloroplasts, from bundle sheath cells of leaves from C4-plants (corn), are characterized by an extensive development of stroma thylakoids with only occasional rudimentary grana. The percentages of appressed membranes are in the ranges of 50 to 60%, 80% and 2% for type I, II and III plastids respectively. Striking differences are observed in the fatty acid composition of phosphatidylglycerol molecules. Trans-delta3-hexadecenoic acid is found only in this phospholipid and amounts to 30 to 40%, 50% and less than 8% of total fatty acids in type I, II and III plastids respectively. The comparison of ultrastructural and biochemical data suggests a strong correlation between the amounts of phosphatidylglycerol molecules containing trans-delta3-hexadecenoic acid and the percentages of appressed membranes (grana stacks) within plastid stroma.

Female Balb-C mice received glutamic acid palmitamide (PGt) or linoleamide (LGt) at doses included between 10 and 135 mg.kg-1 (i.p.) and, 90 min after these injections, pentetrazol (PTZ) at 90 mg.kg-1, i.p. PGt (10 or 100 mg.kg-1, i.p.) reduced significantly latencies of first convulsions and lethality and increased the intensity of convulsions after PTZ. This effect disappeared at 135 mg.kg-1, i.p. and, at high doses (up to 150 mg.kg-1, i.p.) PGt antagonized the PTZ convulsions. LGt (10 mg.kg-1, i.p.) had not any significant effect on the PTZ convulsions and antagonized them when administered at a dose of 100 mg.kg-1, i.p. These results, as well as them obtained with PGt and LGt on the haloperidol or reserpine catalepsy, could be the reflection of the preferential impact of LGt in the striatum and of PGt in the limbic structures and in the substantia nigra. At high doses these compounds could reach brain regions with low density of glutamatergic receptors (thalamus, reticular formation) and develop an activating effect able to antagonize the propagation of the PTZ convulsions. These preferential impacts could augur an antiepileptic action for LGT and a promnesient effect for PGt and LGt.

Several lipid soluble compounds: "Triton X-100", "Emulphogene BC-720" and 8-doxyl-palmitic acid behave-like local anesthetics on the in vivo response of Electrophorus electroplax to carbamylcholine and on the in vitro binding of 3-H acetylcholine to the membrane-bound cholinergic receptor from Torpedo.

The distribution of (1-14C) palmitic acid in the brain tissue following the injection into the cerebral ventricles of conscious cats was investigated. The radioactive material was found in the brain tissue surrounding the cerebral ventricles and in the cerebral cortex, but in varying amounts : the smallest amounts were found in the cerebral cortex, while the highest in the thalamus and in the hippocampus. Radioactive material was also found in the peripheral venous blood. The amount of the radioactive material in the grey matter lining the cerebral ventricles as well as in the cerebral cortex was time-dependant. The labelled material in the structures surrounding the cerebral ventricles and in the cerebral cortex increased within first four hours after its intraventricular administration. Thereafter, throughout subsequent 48 hours either it slowly disappeared in the caudate nucleus and in the thalamus, or it was retained in the hypothalamus and in the floor of the IV ventricle.

Incorporation of malonyl-CoA or acetyl-CoA is studied in mouse brain mitochondrial fatty acids. Rupture of mitochondria is necessary ; Triton X-100 gives the best result. Other detergents or sonication are of lesser efficiency. Cofactor requirements have been studied : NADH and NADPH have been tested ; ATP increases biosynthesis and CoA causes an inhibition. Two systems of biosynthesis are involved : -- One is a de novo system using malonyl-CoA. Malonyl-CoA alone is incorporated and synthesizes mainly C16, indicating the existence of a malonly-CoA decarboxylase although elongation of short chain fatty acids cannot be excluded. Addition of acetyl-CoA increases the biosynthesis and palmityl-CoA when added causes an inhibition. -- The other system, using acetyl-CoA, elongates exogenous palmityl-CoA ; endogenous acyl-CoAs are not elongated by acetyl-CoA. All these results are confirmed by radiogas chromatographic studies of the reactions products.

We present a pattern of fractionation of total lipids, leading to the isolation of individual glycolipids, MGDG contains as sugars, a high quantity of galactose and a low level of glucose. The study of the fatty acids distribution shows: a) a high level of saturated short chains fatty acids, b) a high level of palmitic acid (C 16:0, 68% of the total).

Medium chain triglycerides (MCT) (fatty acids with 6-12 C) are absorbed more quickly than long chain triglycerides. Medium chain fatty acids are not incorporated into hepatic triglycerides, but oxidized. If MCT are given alone, they stimulate ketogenesis. Nevertheless MCT are of great interest in the diet of numerous affections of the digestive tract. When long chain triglycerides are not tolerated, MCT can replace them with efficiency.

The purpose of this work was to study the incorporation of [1-14C] palmitic and and [9,10(-3)H] oleic acids, after intravenous administration in the lipids of rat hind leg muscles. The animals were fasting or fed, at rest or swimming during 10 min before test, euthyroid or thyroidectomised. All these animals have been taking the same daily swimming training, during 15 days before the injection of labelled molecules. They were killed 10 min (+/-1)later. The lipidic muscle composition, the incorporation rate of labelled fatty acids in these lipids and the radioactivity distribution among the different lipids in the various cases have been determined. Moreover the plasmatic non-esterified acid radioactivity has been measured. These various values are affected by nutritional, hormonal state, and by physical activity of the animals. Particularly, it seems that supplementary energy spent during swimming test will be covered by the oxidation of different nutriments, according to the nutritional and hormonal state of animals.

Following injection into the cerebral ventricles of conscious cats, (1-14C) palmitic acid was rapidly taken up and incorporated into a variety of brain lipids. The peak of uptake of (1-14C) palmitic acid, about 50% of injected radioactive material, into the brain tissue was obtained within the first 24 h following its administration. Thereafter, the radioactivity slowly decreased reaching the least value by the end of the second week. The most heavily labelled lipids were the phospholipids, while the free fatty acids were appreciably labelled. Small percentage of the radioactive material was found in monoglycerides, diglycerides and triglycerides. The least incorporation was into cholesterol esters.

A glycolipid was found in a strain of Nocardia caviae. It consists of glucose, myristic, palmitic and stearic acids and a polyhydroxylated acid. The structure of this hydroxyacid was demonstrated by the identification of the product glycerol after LiA1H4 reduction of the glycolipid methyl ester and subsequent hydrolysis, by comparison of the infrared spectra of the hydroxyacid and glyceric acid, by gas chromatography of acetylated methyl and ethyl esters of the polyhydroxylated acid and of standard glyceric acid and by mass spectrometry of the diacetylated methyl ester. The hydroxyacid from the glycolipid is D(-)glyceric acid, a compound rarely found amongst natural products.

The gamma-rays of 60Co cause a diminution in the incorporation of palmitic acid in the phosphatidic acids and the neutral fats of rat-liver microsomes. This diminution occurs without morphological change in the microsomal membranes, where the enzymes responsible for this incorporation are situated. Some evidence is offered that lipid peroxides may be involved in this inhibition.

Weaned rats (21-day old, 44 +/- 2 g) were distributed into 3 groups. The first group was raised on a laboratory diet for 7 or 20 days (control group). The second was fed a diet containing 0.07% fat for 1, 2, 3, 7 or 66 days. The third one was fed the low-fat diet for 7 days and then switched to a laboratory chow diet for 1, 2, 5 or 9 days. Cardiolipin (CL) on the one hand and other mitochondrial phospholipids taken as a whole (PLm) on the other hand were prepared from liver mitochondria and their fatty acids analysed. Polyunsaturated fatty acids in PLm (18:2 (n-6), 20:4 (n-6), 22:6 (n-3) acids) decreased abruptly during the first 3 days of fat deficiency and then remained rather stable till day 7. CL behaved in a quite different way. 18:2 (n-6) acid, the major polyunsaturated fatty acid of CL, decreased continuously between day 1 and day 7 from 79% to 33%. A value of 19.6% was reached on day 66. When deficient rats were transferred to an equilibrated diet, the fatty acid profile of PLm was rapidly restored. Major effects were already achieved during the first 24 h and a fatty acid composition identical to that of control rats was reached within 2 days. A considerably longer period (about 9 days) was necessary for CL to reach a level analogous to that of control rats. The diminution of linoleic acid in CL was brought about by increases in the levels of monoenoic acids: palmitoleic (16:1 (n-7)), oleic (18:1 (n-9)) and cis-vaccenic (18:1 (n-7)) acids which accounted for 18.0%, 17.7% and 17.9% respectively on day 7. Increases in the (n-7) monoenes remained comparatively low in PLm, which showed a sharp rise in their oleic acid content (from 3.9% to 12.7% in 3 days). The proportion of cis-vaccenic acid relative to total octadecenoic acids was decreased from 75% to 50% in CL. A similar trend, but of smaller magnitude, was also noticed in PLm.(ABSTRACT TRUNCATED AT 400 WORDS)

Three concentrations (0.5, 1 and 2 per 1000, w/v) of a single batch of trypsin were compared regarding their influence on cultured cardiac cell of newborn rats. All three allowed to obtain cardiac cells in good conditions, as evidence by beating frequencies and [16-14C]-palmitate beta-oxidation. However the 0.5 per 1000 concentration appeared to be the optimal one, inducing a smaller loss of cells during the first two days in culture.

The effect of puromycin on absorption balance and mucosal lipid distribution was studied during intestinal absorption of 14C oleic acid and 3H palmitic acid, using the isolated intestinal loop of male and female rats in situ. In puromycin-treated animals, mucosal lipid uptake was reduced and mucosal lipid content increased, particularly with oleic acid and in male rats. The phospholipids were significantly reduced. As revealed by mucosal accumulation of free fatty acids, esterification was particularly inhibited with oleic acid and in female rats. These results might explain why portal blood radioactivity was higher in treated rats than in the controls. Puromycin effect occurred at different stages of lipid absorption and varied with sex.

The effect of a 36-hour hyperoxia (60 % oxygen) on rabbit lung lipids has been investigated. It has been established that hyperoxia leads to the increase of all lipid fractions in lung tissue and alveolar surfactant, phospholipid and cholesterol being most significantly affected. It has also been found that hyperoxia leads to the decrease of palmitic acid and to the increase of linoleic and arachidonic acids almost in all lipid fractions. Marked changes in the positional distribution of fatty acids in alveolar surfactant phosphatidylcholine have also been observed. The possible mechanisms of the effect of oxygen on lung lipid metabolism have been discussed, and the consequences ensuing from it which could affect the structural organization of membranes have been evaluated.

The authors report on their study of the ratio of palmitic acid to stearic acid (P/S) in the pharyngeal secretions of the newborn before the sixth hour of life. Four groups of infants were studied: 78 infants used as controls who hac no respiratory distress, 36 with hyaline membrane disease, 16 with transitory respiratory distress and 5 with perinatal asphyxia. The aetiological diagnosis of the respiratory distress was based on clinical as well as radiological and biological criteria. The P/S ratio is always less than 3 with hyaline membrane disease and above 3 in asphyxias. In the control group and the group with transitory respiratory distress the ratio ranged between 1.3 and 14 which was evidence of false negative results, probably attributable to treatment with cortisone given to the mother in premature labour in a certain number of cases. Study of the P/S ratio in amniotic fluid and in the pharyngeal secretions of 27 children born by Caesarean operation embodies a contradiction in the results the newborns in whom the ratio in the amniotic fluid was greater than 3 never had respiratory distress although the ratio studied at the same time in the pharyngeal secretions was low and sometimes less than 3.

In brain microsomes, palmitate and stearate elongation involve a membrane lipid-bound substrate. After elongation by malonyl-CoA, acyl-products are partially bound to proteins. Acyl-proteins are not found when endogenous fatty acid elongation takes place. In the dysmyelinating Quaking mouse mutants, "stearyl-membrane" substrate formation is normal; thus, the deficiency observed in very long chain fatty acid formation is not due to a lack in substrate formation.

Fetal lung maturity has been studied both by silica gel chromatography of phospholipids and gas liquid chromatography of fatty acids. Lecithin/sphingomyelin (L/S) ratios and palmitic/stearic (P/S) ratios were compared. A good correlation was obtained. However, when the L/S ratio has an intermediate value (1.5 less than or equal to L/S less than 2) making it difficult to judge the fetal lung maturity, the P/S ratio expresses the lung maturity more accurately.

1-14C Palmitate uptake by isolated rat plantaris muscle was determined over a 5-min. period following preincubation at 37 degrees C in the presence either of increasing concentrations of palmitate or of other fatty acids, carbohydrates and 2-4 DNP or under anaerobic conditions. Palmitate uptake shows a saturation kinetics and is reduced when the incubation medium contains other fatty acids, carbohydrates, 2-4 DNP on under anaerobic conditions. It is suggested that palmitate uptake could depend on presence of glucose and metabolic energy.