Do blood cells mimic gene expression profile alterations known to occur in muscular adaptation to endurance training?

Exercise is known to upregulate mRNA synthesis for carnitine palmitoyl transferase1 (CPT1) and possibly also other mitochondrial carnitine acyltransferases in muscle tissue. The aim of this study was to test whether such an adaptation of oxidative metabolism in skeletal muscle is a systemic process and consequently, also affects other cells. Messenger RNA levels of five genes [carnitine palmitoyl transferases 1 and 2 (CPT1 and CPT2), carnitine acetyltransferase (CRAT), carnitine palmitoyltransferase 2 (CPT2), microsomal carnitine palmitoyltransferase (GRP58) and organic cation transporter (OCTN2)] were determined with quantitative real time polymerase chain reaction (PCR) in blood cells and in muscle biopsy samples from six cross country skiers before and 6 months after a high volume/low intensity exercise training, when training had elicited a significantly slower rate of lactate accumulation. Quantitative real time PCR showed that levels of mRNA in blood cells correlated significantly (CPT1B: P< 0.001) with those in muscle tissue from the same donors. After 6-months training, there was a 15-fold upregulation of CPT1B mRNA, a six to ninefold increase of CRAT mRNA, of CPT2 mRNA, GRP58 mRNA, and of OCTN2 mRNA. The observation of a concordant stimulation of CPT1, CPT2, CRAT, GRP58 and OCTN2 transcription in blood cells and muscle tissue after 6-month-endurance training leads the hypothesis of a common stimulation mechanism other than direct mechanical stress or local chemical environment, but rather humoral factors.

Effect of the hemoregulatory peptide (pEEDCK)2 (pyroGlu-Glu-Asp-Cys-Lys)2 and MIP-1alpha is reduced in bone marrow cultures from patients with chronic myeloid leukemia (CML).

The granulocyte-derived hemoregulatory peptide pyroGlu-Glu-Asp-Cys-Lys = pEEDCK is known to keep hematopoietic cells quiescent. When oxidized to its dimeric form (pEEDCK)2, it activates growth of hematopoietic progenitors in association with stroma-derived cytokines. (pEEDCK)2 has a Cys-Cys motif which is also a typical feature of the macrophage inflammatory protein (MIP-1alpha). The present study was designed to analyze differences between the response of normal and leukemic progenitor cells to (pEEDCK)2 or MIP-1alpha. When long-term bone marrow cultures (LTBMCs) were incubated with (pEEDCK)2 or MIP-1alpha and/or cytokines, the stimulatory effect on colony-forming units-granulocyte/erythroid/macrophage/megakaryocyte of LTBMC from chronic myeloid leukemia (CML) patients was less than 50% compared to LTBMC from healthy humans. No difference in oncogene expression could be observed in LTBMC from CML patients regarding reduction of Philadelphia chromosome-associated transcription of the BCR-ABL gene. With respect to the expression of growth and differentiation-associated genes (Galpha16, 5-lipoxygenase, phospholipaseA2, c-kit, and CD34), which were analyzed from LTBMC by semiquantitative reverse transcriptase-polymerase chain reaction, the same transcription rate was observed in CML patients and healthy donors. However, two isoforms of a key enzyme of oxidative metabolism, carnitine palmitoyltransferase (CPT1A and CPT1B), showed 50-fold higher expression rates in LTBMC cells of healthy donors compared to CML patients. It is known that a decrease in oxidative metabolism is associated with an increase in redox equivalents in malignancy. This might result in a reduction of disulphide bonds in (pEEDCK)2 or MIP-1alpha, thus inducing a downregulation of these factors in bone marrow from CML patients.

Participation of carnitine palmitoyltransferase in the synthesis of dipalmitoylphosphatidylcholine in rat alveolar type II cells.

We have investigated the role of carnitine palmitoyltransferase (EC 2.3.1.21) in pulmonar type II pneumocyte, a lung cell responsible for the synthesis of surface active lipids. Adult type II pneumocytes were isolated from rat lung and purified by differential adherence. When these lung cells were incubated with radioactive palmitate, the percentage of radioactivity recovered into dipalmitoylphosphatidylcholine (DPPC), a major surface active lipid, was almost 60% with respect to total phosphatidylcholine (PC) molecular species. Cellular lysates from type II pneumocytes contained detectable amount of carnitine palmitoyltransferase (CPT) activity (1 nmol/min/mg). Most of the CPT activity found in these cells could be inhibited by incubating them for 60 min with 5 microM tetradecylglycidic acid (TDGA), a specific and irreversible CPT inhibitor of the malonyl-CoA sensitive CPT isoform (CPT I). TDGA treatment of adult type II pneumocytes caused a significant reduction in the incorporation of radioactive palmitate into PC, though this effect did not seem to be specific for DPPC. TDGA affected the incorporation of radioactive palmitate at the sn2 rather than the sn1 position of the glycerol backbone of PC. The incorporation of radioactive palmitate into DPPC was also observed when these lung cells were incubated with palmitate-labeled palmitoyl-L-carnitine. Our data suggest that type II pneumocyte CPT may play an important role in remodelling PC fatty acid composition and hence DPPC synthesis.

Effects of short-term leptin exposure on triglyceride deposition in rat liver.

Leptin has recently been suggested to play a role in the pathogenesis of hepatic steatosis. Consequently, this study was designed to examine the direct effects of portal leptin on the intrahepatic lipid contents in the postabsorptive state. Rat livers (n = 6 per group) were perfused in a recirculating system and portally infused with leptin (0.5 nmol/L, 5 nmol/L, and 25 nmol/L), insulin (10 nmol/L), leptin (5 nmol/L) plus insulin (10 nmol/L), glucagon (1 nmol/L), or vehicle (control). Intrahepatic contents of triglycerides, free cholesterol, cholesteryl esters, and free fatty acids were determined from the lipid extract of frozen livers by capillary gas chromatography. Short-term leptin infusion increased total triglycerides in a concentration-dependent (0.5 nmol/L: 2.8 +/- 0.4 mg/g, 5 nmol/L: 7.0 +/- 0.5 mg/g, 25 nmol/L: 8.3 +/- 1.0 mg/g) and time-dependent manner. Total triglycerides also rose during exposure to insulin plus leptin (7.2 +/- 0.6 mg/g) but fell during glucagon infusion (2.6 +/- 0.2 mg/g; control: 4.3 +/- 0.3 mg/g; P <.05). Leptin, insulin, and glucagon increased intrahepatic free cholesterol (P <.05). Free fatty acids were also higher during leptin exposure (0.5 nmol/L: 1.28 +/- 0.08 mg/g, 5 nmol/L: 0.47 +/- 0.01 mg/g, 25 nmol/L: 0.48 +/- 0.04 mg/g, control: 0.38 +/- 0.03 mg/g; P <.05). In conclusion, hyperleptinemia increases hepatic triglyceride content and may therefore contribute to hepatic steatosis in hyperleptinemic obese patients.

Effects of prenatal treatment with betamethasone, L-carnitine, or betamethasone-L-carnitine combinations on the phosphatidylcholine content and composition of the foetal and maternal rat lung.

Pregnant rats received 0.10 or 0.20 mg/kg body weight betamethasone, or 100 mg/kg body weight L-carnitine, or L-carnitine 100 mg/kg plus betamethasone 0.05 or 0.10 mg/kg body weight, or saline (controls) for three days before delivery of foetuses at day 19 of gestation. Dose-related effects on the dipalmitoyl phosphatidylcholine content and the phosphatidylcholine species composition of foetal and maternal lungs were determined. Betamethasone (0.10 and 0.20 mg/kg) or L-carnitine (100 mg/kg) significantly increased (p < 0.05) the dipalmitoyl phosphatidylcholine content in the foetal lungs, while only small changes were found in relative terms. Combinations of betamethasone (0.05 or 0.10 mg/kg) with L-carnitine (100 mg/kg) also significantly increased the dipalmitoyl phosphatidylcholine content of the foetal lungs above control values (p < 0.01) and above the values achieved with betamethasone alone (p < 0.05). In the maternal lungs a significant increase of the dipalmitoyl phosphatidylcholine content above the control values was only found after treatment with betamethasone-carnitine combinations, whereas compared with the foetal lung the relative increase of dipalmitoyl phosphatidylcholine as a fraction of total phosphatidylcholine was more pronounced after betamethasone treatment. The gas chromatographic method used separates two monoenoic phosphatidylcholine species with 32 carbon atoms in the acyl residues. These two phosphatidylcholine species showed striking differences between adult and foetal lungs. Palmitoleyl palmitoyl phosphatidylcholine predominates in the maternal lung, whereas palmitoyl palmitoleyl phosphatidylcholine is the major monoenoic phosphatidylcholine species with 32 carbon atoms in the foetal lung. These two species were not affected in maternal or foetal lung by betamethasone or L-carnitine treatment. In contrast, after treatment with betamethasone-carnitine combinations, a significant increase of the fraction of palmitoyl palmitoleyl phosphatidylcholine was found in foetal but not in the maternal lung. The results of the present study demonstrate that maternal glucocorticoid and carnitine treatment affects the maternal as well as the foetal lung but with different effects on the dipalmitoyl phosphatidylcholine content and phosphatidylcholine species composition.

[Animal experiment and clinical studies of the significance of carnitine for energy metabolism in pregnant patients and the fetus during the pre- and perinatal period]. / Tierexperimentelle und klinische Untersuchungen über die Bedeutung des Carnitins für den Stoffwechsel der Schwangeren und des Feten während der Prä- und Perinatalperiode.

Carnitine was discovered at the beginning of this century, but was nearly forgotten until its importance in fatty acid metabolism was established 50 years later. In the past years, several other functions of carnitine in cellular metabolism have been described. The lung contains more than 40 different cell types, most of them involved in lipid metabolism. Pulmonary surfactant, a complex of 90% lipids and 10% lung specific apoproteins, is synthesized and secreated from type II cells. Surfactant is present as a monolayer at the air-liquid interface in the alveoli and decreases surface tension. Dipalmitoyl phosphatidylcholine (DPPC) is functionally and quantitatively the most important constituent of the surfactant complex. A deficiency in fetal lung surfactant is the primary cause of the respiratory distress syndrome (RDS), the most severe complication of preterm infants. Glucocorticoids are frequently used to accelerate fetal pulmonary maturation. However, a considerable number of infants fail to respond to this therapy. Maternal administration of L-carnitine significantly increased the DPPC content of fetal rat lungs. The effect of maternal treatment with a carnitine-betamethasone combination was synergistic, especially with lower betamethasone doses. Consequently the minimal dose of betamethasone which affects the DPPC content and accelerate the morphological maturation of the fetal lung was determined. This minimal dose in combination with L-carnitine increased the DPPC content on day 19 of gestation to levels found on the 20th gestational day which allows the survival of most of the preterm rats (term 22 days). Results of clinical trials show that antenatal treatment with a low dose betamethasone-L-carnitine combination has a clear advantage over standard betamethasone therapy. A multicenter study is in progress. Plasma carnitine levels at delivery are decreased to about half of the concentrations seen in non-pregnant women. Similar low levels are found only in patients with carnitine deficiency. Already in the 12th week of gestation the mean whole blood and plasma carnitine levels were found to be significantly lower than those of controls. The reason for increased excretion of acylcarnitines during pregnancy is not known, but could be a detoxifying function similar to that found in patients with inborn errors of fatty acid metabolism and organic acidurias. Carnitine substitution (1 g daily) from the 20th gestational week up to parturition resulted in an increase of free carnitine levels in maternal plasma. A dosage of 0.5 g/day was without effect. Prolonged substitution in pregnant women, especially in risk pregnancies may be preferable to high doses of carnitine administered shortly before imminent premature delivery.

Combined therapy with Ukrain and chemotherapy in ovarian cancer (case report).

A patient with adenocarcinoma in the right ovary with lymphangitis carcinomatosa, staged as G II-G III pT3, pNX, pMX, was treated after palliative surgery by chemotherapy and, simultaneously, with Ukrain. Two and a half years after treatment the patient is without any signs of tumour recurrence. Her condition is excellent.

Prenatal effects of betamethasone-L-carnitine combinations on fetal rat lung.

Lungs of fetal rats between the 18th and 20th gestational day (total gestation lasting 22 days) were examined. There was a significant increase (p < 0.01) of the dipalmitoyl phosphatidylcholine content from day 19 to day 20 of gestation. In the second trial, pregnant rats were treated with different doses of betamethasone, L-carnitine, betamethasone-L-carnitine combinations, and saline (controls) for three days before Cesarean section on the 19th gestational day. Maternal injections of 0.10 mg/kg body weight betamethasone and 100 mg/kg body weight L-carnitine significantly (p < 0.05, p < 0.01 respectively) increased the dipalmitoyl phosphatidylcholine content of fetal lungs. Combinations of either 0.05 or 0.10 mg/kg body weight betamethasone with 100 mg L-carnitine also significantly increased the dipalmitoyl phosphatidylcholine content of the fetal lungs above control values (p < 0.001) and values achieved with betamethasone alone (p < 0.05). Maternal treatment with a betamethasone-L-carnitine combination on day 19 of gestation resulted in dipalmitoyl phosphatidylcholine levels comparable to those found on the 20th gestational day during normal lung maturation. Fetal rats delivered on the 20th gestational day survived, while fetuses delivered on the 19th gestational day did not survive.

Pregnancy-related changes of carnitine and acylcarnitine concentrations of plasma and erythrocytes.

Total-, free-, and acylcarnitine concentrations were determined in whole blood, plasma, and red blood cells of 88 women during pregnancy. Already in the 12th week of gestation the mean whole blood carnitine level was significantly (p < 0.01) lower than those of the controls. From the 12th gestational week up to parturition there was a further significant (p < 0.01) decrease. This reduction of total carnitine in whole bloods was mainly caused by a significant (p < 0.01) decrease of free carnitine levels, since no marked changes of short chain acylcarnitine values were found throughout pregnancy. The contribution of red blood cell L-carnitine to whole blood carnitine increased significantly (p < 0.05) to 61% at delivery versus 39% (controls). In umbilical cord blood free and total carnitine levels were significantly (p < 0.05) higher than the corresponding maternal levels. The contribution of red blood cell L-carnitine to whole blood carnitine was higher in cord blood than in maternal blood. The results of the present study demonstrate that during pregnancy whole blood and plasma carnitine levels decrease to those levels found in patients with carnitine deficiency. Also the percentage of acylcarnitine on total carnitine, found in the present study, is characteristic for a secondary carnitine deficiency. Thus L-carnitine substitution in pregnant women, especially in risk pregnancies, may be advantageous.

Antenatal betamethasone-dose-effects on fetal rat lung morphology and surfactant.

Pregnant rats received betamethasone 0.02, 0.05, 0.10, or 0.20 mg/kg body weight/day or saline (controls) for three days before delivery of fetuses at day 19 of gestation. Dose related effects on morphology, dipalmitoyl phosphatidylcholine content, and phosphatidylcholine species composition of the fetal lungs were evaluated. Injection of 0.02 and 0.05 mg/kg body weight betamethasone resulted in cellular differentiation of some cells, but the increase in dipalmitoyl phosphatidylcholine content was not significant. Dosages of either 0.10 or 0.20 mg/kg body weight resulted in markedly accelerated organ differentiation, complete cytodifferentiation of type II cells, and markedly increased numbers of lamellar bodies per alveolar type II cell. Compared to the controls, maternal administration of 0.10 or 0.20 mg/kg betamethasone caused significant increases of both fetal lung dipalmitoyl phosphatidylcholine content, and the fraction of dipalmitoyl phosphatidylcholine of total phosphatidylcholine. None of the parameters differed between the groups that were treated with 0.10 or 0.20 mg/kg body weight betamethasone respectively. Diminution of lung DNA content was significant after treatment with betamethasone in doses of 0.05, 0.10, and 0.20 mg/kg body weight. The results of the present study suggest that maternal treatment with lower doses than those in common usage may be successful in prevention of respiratory distress syndrome, and that higher dosages do not confer any additional advantage.

[L-carnitine-betamethasone combination therapy versus betamethasone therapy alone in prevention of respiratory distress syndrome]. / L-Carnitin-Betamethason Kombinationstherapie versus alleiniger Betamethasontherapie als Prophylaxe des Atemnotsyndroms.

In this prospective randomised study the effects of antenatal treatment with a low dose betamethasone (2 mg/1 day)-L-carnitine (4 g/5 days) combination were compared with those of a high dose betamethasone, given alone (8 mg/2 days) on the prevention of respiratory distress syndrome (RDS) and mortality in preterm infants. One-hundred women entering the trial gave birth to 109 liveborn infants, 55 in the betamethasone group (A), 54 in the betamethasone-L-carnitine combination group (B). Eight of the 55 (14.5%) infants in group A developed RDS, four of the 54 (7.3%) in group B, which was significantly more (p < 0.05), although in group B the betamethasone dose was dramatically reduced. The mortality also was significantly lower after treatment with a betamethasone-L-carnitine combination compared to betamethasone alone (4 of 55 infants or 7.3% in group A versus 1 of 54 infants or 1.8% in group B, p < 0.05). The present results demonstrate that in combination with L-carnitine, the betamethasone dose is markedly reducible with a concomitant significant reduction of the incidence of RDS and mortality of premature newborns.

Chelidonium majus L. (Ukrain) in the treatment of cancer patients.

Ukrain, a semi-synthetic thiophosphoric acid compound of alkaloid chelidonine isolated from Chelidonium Majus L., Tris(2-([5bS-(5ba,6b,12ba)]-5b,6,7,12b,13,14- Hexahydro-13-methyl][1,3]-benzodioxolo[5,6-c]-1,3-dioxolo[4, 5- i]phenanthridinium-6-ol]-Ethaneaminyl) Phosphinesulfide 6HCl, causes a regression of tumours and metastases in many oncological patients. More than 400 documented patients with various carcinomas in different stages of development have been treated with Ukrain. The authors report on only three different cases treated with preparation Ukrain. Ukrain can be helpful in improving the general condition and prolonging life by reduction of the tumour progression and its immunomodulating effect on the organism.

Response to thyroxine of lamellar bodies, peroxisomes and peroxisomal enzymes in the adult rat lung.

Adult male rats were fed a standard diet containing 25 mg/kg L-thyroxine for 2 weeks. The hyperthyreotic condition of the animals was checked by monitoring the metabolic rates and liver glycerol-3-phosphate dehydrogenase. In the postnuclear fraction of the lung the activity of fatty acyl-CoA oxidase, the enzyme responsible for the rate limiting first step of peroxisomal fatty acid beta-oxidation, showed a twofold increase. Catalase, the marker enzyme of peroxisomes, showed a similar increase. Electron microscopic examination of alveolar type II cells did not reveal changes in the number and distribution frequency of peroxisomes and lamellar bodies. Similarly the content of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (dipalmitoyl phosphatidylcholine), the main constituent of alveolar surfactant, was not altered significantly by thyroxine feeding. On the other hand the volume density of the peroxisomal compartment was found to be doubled according to the measured increase of catalase and acyl-CoA oxidase. Our data suggest that the induction of peroxisomal matrix enzymes, such as catalase and fatty acyl-CoA oxidase, does not influence the surfactant content.

Pulmonary surfactant in bronchoalveolar lavage after canine lung transplantation: effect of L-carnitine application.

Pulmonary surfactant during lung transplantation was investigated in the control group of a canine single lung transplantation model by measuring dipalmitoyl-phosphatidylcholine, the main phosphocholine fraction of surfactant in bronchoalveolar lavage. In a second group of dogs, L-carnitine, an essential cofactor for transfer of long-chain fatty acids into the mitochondria, was applied. Organ function after pulmonary artery flushing with modified Euro-Collins solution and hypothermic storage for 4 hours was adequate in both groups, with significantly higher arterial oxygen pressure levels in the L-carnitine group after 12 (p less than 0.05) and 24 (p less than 0.025) hours, respectively. In the control group, a reduction of the dipalmitoyl-phosphotidylcholine portion on total phosphotidylcholines was observed 4 and 12 hours after transplantation of the left lung (p less than 0.005 and p less than 0.01, respectively, both specified by Student's t test for dependent data, not significant by Bonferroni correction). In the simultaneously stored right lungs, a constant fall of the dipalmitoyl-phosphotidylcholine portion was demonstrated. In the L-carnitine group, significantly higher dipalmitoyl-phosphotidylcholine levels were observed in the transplanted left lungs after 4 hours (p less than 0.01) and in the continuously stored right lungs after 24 hours (p less than 0.005), when compared with the control group. These results suggest that dipalmitoyl-phosphotidylcholine portion on total phosphotidylcholine decreases parallel to the extent of the ischemic damage. Furthermore, the application of L-carnitine improved pulmonary function after transplantation, possibly by reducing the impairing effect of ischemia on alveolar type II cell metabolism and thereby on pulmonary surfactant system.

Effect of carnitine on foetal rat lung dipalmitoyl phosphatidylcholine content and lung morphology. Carnitine and lung surfactant, I.

Lungs of foetal rats between the 16th and 20th gestational day (total gestation lasting 22 days) were examined. There was a striking increase of both total phosphatidylcholine and dipalmitoyl phosphatidylcholine from day 19 to 20 of gestation. The carnitine content increased continuously from day 17 both in the foetal lungs and livers. In both organs, the increase in short-chain acylcarnitine was more pronounced than the increase in free carnitine. Compared with an untreated control group, treatment of the mother with L-carnitine (from day 16 to 18 of gestation, with 60, 80, and 100 mg/kg.d L-carnitine, respectively) resulted in significant increases in both total phospholipid (p less than 0.05 in all treated groups) and dipalmitoyl phosphatidylcholine (p less than 0.05, p less than 0.01, p less than 0.001, corresponding to maternal treatment with 60, 80, 100 mg/kg.d, respectively) on the 19th gestational day. The results are in accordance with morphological evaluations: with increasing carnitine-dosage, increasing numbers of lamellar bodies in type II cell progenitors were found. The enhanced dipalmitoyl phosphatidylcholine content is a consequence of enhanced phospholipid synthesis in remarkably undifferentiated type II cells largely lacking membrane structures and cell organelles capable of phospholipid synthesis. Thus, in general, carnitine treatment seems to stimulate foetal lung phospholipid synthesis, thereby enhancing the dipalmitoyl phosphatidylcholine content.

Determination of plasma free fatty acids, free cholesterol, cholesteryl esters, and triacylglycerols directly from total lipid extract by capillary gas chromatography.

An accurate capillary gas chromatographic method using different internal standards for determining free fatty acids, cholesterol, cholesteryl esters, and triacylglycerols in plasma and other biological sources is described. It is designed to give information about species composition and, consequently, more detailed information about changes in lipid metabolism of patients suffering from metabolic disorders. After plasma extraction the lipids, except phospholipids, are directly examined without any further derivatization. For free fatty acid determination the programmed temperature vaporizer (PTV) injector was heated from 40 degrees C (sample introduction) to 190 degrees C. In a second gas chromatographic run the PTV-injector system was heated from 60 degrees C (sample introduction) to 400 degrees C, enabling the determination of free cholesterol, cholesteryl esters, and triacylglycerol species, differing in the number of carbon atoms. Evaluation of the values obtained resulted in coefficients of variation (%) of 1.0-2.8, 2.0, 1.29-2.24, and 2.8, for free fatty acid standards, plasma free fatty acids, cholesterol and cholesteryl ester standards, and plasma total cholesterol, respectively. Free fatty acids, cholesterol, and cholesteryl esters were not influenced by storage of plasma at -24 degrees C up to 4 days prior to extraction. The results of the gas chromatographic method and the enzymatic methods correlated well. Determination by gas chromatography yielded higher total cholesterol and lower triacylglycerol values than those values obtained by enzymatic methods.

[Dynamic measurement of surface tension versus gas chromatography dipalmitoylphosphatidylcholine analysis of amniotic fluid; a comparison of a bedside method with a highly specialized surfactant analysis]. / Dynamische Oberflächenspannungsmessung versus gaschromatographische DPPC-Analyse im Fruchtwasser; ein Vergleich einer "Bedside" Methode mit einer hochspezialisierten Surfactantanalyse.

The diagnosis of fetal lung maturity by analysis of the amniotic fluid still constitutes a present-day problem. In this study the results of measuring the dynamic surface tension by the Wilhelmy-balance were compared with the DPPC (Dipalmitoyl-Phosphatidyl-Choline) and lecithin species-analysis by the quantitative capillary gas chromatography. The first possibility is a "bed-side"-method, which evaluates the effect of the surfactant in the amniotic fluid in its entirety, whereas the second method represents a highly specialized laboratory procedure analysing the most important part of surfactant contact. The surface tension of amniotic fluid is expressed by its value at 20% of the extension of the surface (gamma-min) as well as the hysteresis area. We were able to show a better correlation between the hysteresis area and the DPPC (r = 0.422, p less than 0.012) than between the gamma min and the DPPC (r = 0.370, p less than 0.031). The correlation between the hysteresis area respectively between the gamma-min, and the second gas chromatographically detectable component of the surfactant, PC 30 was not so distinct (r = 0.068, p less than 0.744; R = -0.355, p less than 0.075). Obviously this component of the surfactant is not as active on the surface and therefore not as important. Further we could show, a negative correlation to the lecithin species PC 34; with increasing surface activity and increasing lung maturity this lecithin species quantitatively recedes into the background.

L-carnitine substitution in patients on chronic hemodialysis.

Patients on chronic hemodialysis with hyperlipidemia were found to respond either with decreased levels (responders) or with a further increase of the plasma triglyceride levels (nonresponders) to a carnitine substitution therapy. The aim of the present study was to find possible predictors to distinguish between responders and nonresponders prior to the initiation of therapy. Since it is suggested that erythrocytes are involved in carnitine transport to tissues, it was of interest to determine plasma and erythrocyte carnitine concentrations in the hemodialyzed patients before and during carnitine substitution therapy and to compare the results with those of healthy controls. Before therapy, comparatively lower plasma levels of both free and total carnitine, but higher portions of short-chain acylcarnitine on total carnitine were found in all patients. In erythrocytes, the nonresponders showed significantly higher total carnitine levels, compared to responders and controls. After the start of carnitine substitution, the increase of total plasma carnitine during the substitution period corresponded with the carnitine dose administered in responders, in nonresponders the highest carnitine values were found in the second week when the lower carnitine dose was administered. The changes of the plasma short-chain acylcarnitine levels with time were very similar to those of plasma triglycerides. All patients showed a time-delayed accumulation of carnitine in erythrocytes and, interestingly, markedly higher concentrations in the second week when the lower carnitine dose was administered. The results of the present study demonstrate that the erythrocyte carnitine content is a reliable predictor to distinguish between responders and nonresponders prior to the start of a carnitine substitution therapy.

Determination of triacylglycerols in serum by capillary gas chromatography with trinonadecanoylglycerol as internal standard.

An accurate capillary gas-chromatographic method with trinonadecanoylglycerol as internal standard for determining triacylglycerols in human serum and other biological sources is described. After serum extraction, total triacylglycerol and triacylglycerol species (differing in the number of carbon atoms in the acyl radicals) are directly determined without any further sample manipulation. In addition, from the same gas-chromatographic run the data obtained by the integrator record are compared with those of a computer data acquisition system. Evaluation of the triacylglycerol values resulted in a coefficient of variation (CV) of 2.08% (computer evaluation). Simultaneous evaluation of data obtained from tripalmitoylglycerol and tristearoylglycerol standards resulted in CV of 2.04 and 1.99%, respectively (computer evaluation), and 6.63 and 4.84%, respectively (integrator evaluation). Gas chromatography at lower elution temperature resulted in better separations but enhanced CV values up to about 4%. Triacylglycerol values were not influenced by storage of plasma at -20 degrees C up to 4 days prior to extraction.