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J Desgres

Publications and source records attributed to J Desgres.

At least 19 recordsLinked to original sources

Removal of branched-chain amino acids and alpha-ketoisocaproate by haemofiltration and haemodiafiltration.

Venovenous haemofiltration (VVHF) and haemodiafiltration (VVHDF) were performed with a neonatal haemo(dia)filter (Miniflow 10, Hospal) on 8 anaesthetized rabbits infused with branched-chain amino acids (leucine, isoleucine and valine) and alpha-ketoisocaproate. The branched-chain amino acids (BCAA) and alpha-ketoisocaproate blood levels were close to those previously observed in neonates with maple syrup urine disease when extracorporeal blood purification was required. VVHF and VVHDF performances were assessed with two different blood flows (Qb = 8.3 and 16.6 ml/min). VVHDF was performed with four dialysate flow rates (Qd = 0.5, 1.0, 2.0 and 3.0 L/h). Within each period, clearances of the three BCAA were strictly similar. BCAA clearances obtained by VVHF were similar to ultrafiltration rates (respectively, 0.78 +/- 0.14 and 1.79 +/- 0.28 ml/min at high and low Qb; p < 0.05). The alpha-ketoisocaproate clearances obtained by VVHF were 0.39 +/- 0.17 and 0.92 +/- 0.43 ml/min at low and high Qb (not significantly different). Whatever the Qd value, the VVHDF procedures always allowed higher BCAA and alpha-ketoisocaproate clearances as compared with the corresponding VVHF period with similar Qb. BCAA clearances obtained by VVHDF with a 0.5 L/h dialysate flow were 4.1 +/- 0.5 and 5.4 +/- 0.5 mL/min at low and high Qb, respectively. The concurrent alpha-ketoisocaproate clearances were 2.5 +/- 0.8 and 2.9 +/- 1.0 ml/min.

Amino Acids, Branched-Chain

Use of peritoneal dialysis, continuous arteriovenous hemofiltration, and continuous arteriovenous hemodiafiltration for removal of ammonium chloride and glutamine in rabbits.

OBJECTIVE: We compared the ability of peritoneal dialysis, hemofiltration, and continuous hemodiafiltration to remove infused ammonium chloride. STUDY DESIGN: Anesthetized adult rabbits received an intravenous infusion of ammonium chloride. Two methods of removal of ammonium chloride were performed in each animal and compared. In group 1 (n = 6), peritoneal dialysis (dialysate = 75 ml.kg-1) and continuous arteriovenous hemofiltration (CAVH) with a polysulfone 800 cm2 hemofilter (Minifilter Plus; Amicon Division, W. R. Grace & Co., Danvers, Mass.) were simultaneously performed for 40 minutes. In group 2 (n = 6), peritoneal dialysis and continuous arteriovenous hemodiafiltration (CAVHD) (dialysate flow = 1000 ml.hr-1) were simultaneous performed for 40 minutes. In group 3 (n = 6), CAVH and CAVHD were performed successively in random order for 30 minutes each. RESULTS: Animals had high and stable ammonium chloride and glutamine plasma levels during the experimental procedure. No significant difference in ammonium chloride clearance was observed between PD and CAVH (group 1). In comparison with PD or CAVH, CAVHD resulted in significantly higher clearances of ammonium chloride (40% +/- 10% vs 96% +/- 34%, respectively) and of glutamine (195% +/- 17% vs 77% +/- 25%, respectively). CONCLUSION: The overall results indicate that CAVHD should be considered for hyperammonemia when peritoneal dialysis is indicated but unfeasible or inefficient.

Ammonium Chloride

Removal of branched-chain amino acids by peritoneal dialysis, continuous arteriovenous hemofiltration, and continuous arteriovenous hemodialysis in rabbits: implications for maple syrup urine disease treatment.

Renal elimination of branched-chain amino acids (BCAA) is low in maple syrup urine disease, and peritoneal dialysis may be required in an emergency situation for removal of the three BCAA (leucine, isoleucine, and valine). However, failures of BCAA removal by peritoneal dialysis have been reported, especially in neonates. Therefore, we tested the ability of continuous hemofiltration and continuous hemodialysis to remove BCAA as compared with peritoneal dialysis. Experiments were conducted in 15 anesthetized adult rabbits infused with leucine, isoleucine, and valine. In group 1 (n = 7), peritoneal dialysis (dialysate = 75 mL/kg) and continuous arteriovenous hemofiltration with a polysulfone 800-cm2 hemofilter were simultaneously performed during 40 min. In group 2 (n = 8), continuous arteriovenous hemofiltration and continuous arteriovenous hemodialysis were successively performed during 30 min in a randomly settled order. Animals had high and stable BCAA plasma levels during the experimental procedure. As compared with peritoneal dialysis, continuous arteriovenous hemofiltration constantly showed a significant increase in clearances of leucine (+159 +/- 99%), isoleucine (+176 +/- 107%), and valine (+125 +/- 76%). In comparison with continuous arteriovenous hemofiltration, continuous arteriovenous hemodialysis constantly showed significant increased values in clearances of leucine (+90 +/- 43%), isoleucine (+95 +/- 45%), and valine (+99 +/- 52%). During continuous arteriovenous hemofiltration and continuous arteriovenous hemodialysis, a significant positive correlation was established between urea clearance and clearances of leucine (r2 = 0.953 and 0.927, respectively), isoleucine (r2 = 0.948 and 0.910, respectively), and valine (r2 = 0.953 and 0.864, respectively).

Amino Acids, Branched-Chain

[Removal of amino acids by continuous hemofiltration and hemodiafiltration].

BACKGROUND: Continuous hemodiafiltration is potentially more efficient than hemofiltration for removing low molecular metabolites. CASE REPORT: A newborn (2100 g) was admitted suffering from acute distress with statuts epilepticus, liver failure with generalized hyperaminoacidemia, hypoglycemia and oligo-anuria. Peritoneal dialysis, performed on the 17th day of life, was ineffective and the patient was treated by continuous hemofiltration alternating with hemodiafiltration. Clearance of amino-acids was studied for 15 minutes under each technique. The amino-acid concentrations were measured in the infused fluid and in the ultrafiltrate. The baby died on the 20th day despite this treatment. RESULTS: Amino acid clearance by hemodiafiltration was 181 +/- 176% greater than by hemofiltration. The mean improvement for all amino acids was 148%, with extremes of +43% for citrulline and 941% for glutamic acid. CONCLUSION: Continuous hemodiafiltration is an efficient method of removing amino acids; it could be used to treat severe inborn errors of metabolism such as leucinosis.

Acute Kidney Injury

Modified nucleotides in Bacillus subtilis tRNA(Trp) hyperexpressed in Escherichia coli.

In the present study, modified nucleotides in the B. subtilis tRNA(Trp) cloned and hyperexpressed in E. coli have been identified by TLC and HPLC analyses. The modification patterns of the two isoacceptors of cloned B. subtilis tRNA(Trp) have been compared with those of native tRNA(Trp) from B. subtilis and from E. coli. The modifications of the A73 mutant of B. subtilis tRNA(Trp), which is inactive toward its cognate TrpRS, were also investigated. The results indicate the formation of the modified nucleotides S4U8, Gm18, D20, Cm32, i6A/ms2i6A37, T54 and psi 55 on cloned B. subtilis tRNA(Trp). This modification pattern resembles the pattern of E. coli tRNA(Trp), except that m7G is missing from the cloned tRNA(Trp), probably on account of its short extra loop. In contrast, the pattern departs substantially from that of native B. subtilis tRNA(Trp). Therefore, the cloned B. subtilis tRNA(Trp) has taken on largely the modification pattern of E. coli tRNA(Trp) despite the 26% sequence difference between the two species of tRNA, gaining in particular the Cm32 and Gm18 modifications from the E. coli host. A notable difference between the isoacceptors of the cloned tRNA(Trp) was seen in the extent of modification of A37, which occurred as either the hypomodified i6A or the hypermodified ms2i6A form. Surprisingly, base substitution of guanosine by adenosine at position 73 of the cloned tRNA(Trp) has led to the abolition of the 2'-O-methylation modification of the remote G18 residue.

Bacillus subtilis

O-ribosyl-phosphate purine as a constant modified nucleotide located at position 64 in cytoplasmic initiator tRNAs(Met) of yeasts.

The unknown modified nucleotide G*, isolated from both Schizosaccharomyces pombe and Torulopsis utilis initiator tRNAs(Met), has been identified as an O-ribosyl-(1"----2')-guanosine-5"-phosphate, called Gr(p), by means of HPLC, UV-absorption, mass spectrometry and periodate oxidation procedures. By comparison with the previously published structure of Ar(p) isolated from Saccharomyces cerevisiae initiator tRNA(Met), the (1"----2')-glycosidic bond in Gr(p) has been postulated to have a beta-spatial conformation. The modified nucleotide Gr(p) is located at position 64 in the tRNA(Met) molecules, i.e. at the same position as Ar(p). Since we have also characterized Gr(p) in Candida albicans initiator tRNA(Met), the phosphoribosylation of purine 64 can be considered as a constant nucleotide modification in the cytoplasmic initiator tRNAs(Met) of all yeast species so far sequenced. Precise evidence for the presence of Gr(p) in initiator tRNAs(Met) of several plants is also reported.

Candida

Adrenal function in HIV infected patients.

UNLABELLED: Since anatomopathological lesions of the adrenal gland have been frequently observed at autopsy in AIDS, we investigated the glucocorticoid function in 63 patients (51 men, 12 women) infected by the human immunodeficiency virus (HIV) in order to determine the incidence and the nature of any adrenocortical abnormalities at various stages of HIV infection. The patients were classified according to the Centers for Disease Control (CDC) recommendations into group II (asymptomatic; N = 13), group III (lymphadenopathy; N = 27) and group IV (clinical manifestations; N = 23). Plasma ACTH and cortisol before and after an exogenous ACTH stimulation test were measured in patients as in 30 age-matched controls. Plasma renin activity and plasma aldosterone before and after ACTH stimulation were also measured in 31 patients (group II: 12; group III: 10; group IV: 9). Compared with controls patients from group II-III had higher levels of ACTH (39.11 +/- 17.01 vs 29.73 +/- 8.53 ng/l; p = 0.003) and basal cortisol (232 +/- 91.2 vs 184.3 +/- 30.9 micrograms/l; p = 0.03). No significant differences were noted between group IV patients and controls as to ACTH and basal and stimulated cortisol levels. Among the 63 patients, only one from group IV had a blunted cortisol response after ACTH stimulation test. Plasma renin activity, and basal and stimulated aldosterone levels in the 3 groups of patients were not different from control values. IN CONCLUSION: 1. Adrenal insufficiency does not seem very frequent in group IV patients and is likely to be a late complication in AIDS. 2. The increased ACTH and basal cortisol levels found in group II and group III patients argue for an early dysregulation of the adrenocortical axis in HIV infection. The exact physiopathological mechanism is not yet known, but an enhanced CRH production by interleukin 1 and/or a direct role of the HIV envelope glycoprotein (gp 120) may explain the high ACTH level in HIV patients.

Acquired Immunodeficiency Syndrome

Correlation between apolipoprotein A-IV and triglyceride concentrations in human sera.

Apolipoprotein A-IV concentration was measured by a newly developed competitive enzyme immunoassay in sera from fasted human subjects (n = 105) whose triglyceride concentrations ranged from 20 to 474 mg/dl (total cholesterol below 260 mg/dl) and in which chylomicrons could not be detected. Mean (+/- SD) apolipoprotein A-IV concentration was 13.0 +/- 2.6 mg/dl in sera with triglyceride levels ranging from 20 to 100 mg/dl, 16.9 +/- 3.7 mg/dl in sera with triglyceride levels ranging from 101 to 250 mg/dl, and 22.7 +/- 6.7 mg/dl in sera with triglyceride levels ranging from 251 to 474 mg/dl. The differences among the three groups were highly significant (P less than 0.001). Moreover, variations of apolipoprotein A-IV concentrations according to the triglyceride levels were noted within the normo-triglyceridemic population. Apolipoprotein A-IV concentration was 12.8 +/- 2.1 mg/dl for triglyceride levels ranging from 20 to 75 mg/dl and 16.4 +/- 3.8 mg/dl for triglyceride levels ranging from 76 to 150 mg/dl (P less than 0.01). In the entire population that was studied there was a significant linear correlation (r = 0.61, P less than 0.001) between the concentrations of serum apolipoprotein A-IV and triglyceride. Although the hypothesis of an unknown factor independently influencing both very low density lipoproteins and apolipoprotein A-IV cannot be ruled out, and although no apolipoprotein A-IV was found in the triglyceride-rich lipoprotein fraction after separation by gel filtration, these data suggest that, in fasting subjects, the secretion of very low density lipoproteins could contribute to the plasma apolipoprotein A-IV level.

Adult

[Neuroendocrine disorders observed in the post-critical phase in epileptic patients].

In 10 epileptic patients with generalized seizures, plasma levels of ACTH, prolactin, FSH, LH, TSH, were measured first within 60 minutes after the crisis, then 3 to 5 days later without changes in antiepileptic drugs. Within 1 hour after the seizure, a significant rise of ACTH and prolactin 3 - 4 folds the levels observed in the 2nd measure was present. This was compared to measures made within 1 hour after a syncope in which case it was not present. The post-critic rise of ACTH and prolactin would appear to be a characteristic of generalized epileptic seizures.

Adolescent

[Treatment of citrullinemia. Apropos of a case followed from birth. Importance of alpha-ketonic acids].

From day 1 to day 3, the protein intake of this neonate was restricted to 1 g/kg/d. It included a) essential amino acids (i.e. histidine, lysine, threonine, tryptophan), b) arginine (1,000 mg/d), c) alphaketoisovaleric 500 mg/d, alpha-ketoisocaproic (500 mg/d), alphaketobetamethylvaleric (500 mg/d), alphaketogammamethylthiobutyric (200 mg/d), betaphenylpyruvic (400 mg/d) acids. 250 mg/kg/d of sodium benzoate were given. Caloric and water intakes were 120 cal/kg/d and 120 ml/kg/d respectively. Afterwards, this procedure was modified according to clinical and biological data including serum ammonia and amino acid levels. Alpha-ketonic acid absorption and metabolism were studied on day 29. Both were fast. The detection of alloisoleucine, which is not metabolized was the consequence of the use of alphaketobetamethylvaleric acid. Until the age of 21 months, clinical and metabolic status was satisfactory. At this time, repeated seizures without metabolic failure were accompanied by psychomotor damages.

Amino Acid Metabolism, Inborn Errors

[Post-crisis elevation of adrenocorticotropic hormone and prolactin in epileptic children].

In six children, aged from 8 to 12 years, presenting with primary generalized epilepsy a significant rise in plasma ACTH and prolactin levels (as compared with levels measured 5 days later) was observed either during a generalized seizure demonstrated by EEG (3 cases) or within 1 hour of a generalized seizure (3 cases). The neurophysiological basis for these post-epileptic endocrine disturbances is a sudden depression of dopaminergic and GABA-ergic pathways. As a result, these endocrine changes, already well documented in adults, may be regarded as a good biological marker of the epileptic origin of a paroxysmal attack.

Adrenocorticotropic Hormone

Preparative electrophoresis of human apolipoprotein E: an improved method.

Apolipoprotein E was isolated from human very low density lipoproteins by a two-step electrophoretic procedure derived from that of Méndez (1982. Anal. Biochem. 126: 403-408). It included separation in a sodium dodecylsulfate polyacrylamide slab gel, transfer into an agarose gel, and extraction by ultracentrifugation for 30 min. No protein labeling, dialysis, or concentration procedures were needed. The method was fast, showed an excellent protein recovery, and could be suitable as a general method of protein isolation by polyacrylamide gel electrophoresis.

Apolipoproteins E

[GABAergic control of hypophyseal gonadotropic function and prolactin. Demonstration by valproic acid].

While there is well-known evidence for dopaminergic control over gonadotrophic and Prolactin functions, the way gamma-aminobutyric acid (Gaba) acts and the routes through which it acts are not so well known. Valproic acid stimulates cerebral Gabaergic tracts. It was therefore used by the authors to study first the basal levels of LH FSH and Prolactin and the way they reacted after two months treatment with this anti-convulsant. The authors noted a decrease of LH-RH stimulated LH and a decrease of the basal levels or Prolactin in TRH stimulated Prolactin. So Gaba can be a neuro-modulator of the hypothalamo-pituitary axis, acting synergically with the dopaminergic tracts to decrease Prolactin secretion but opposing the dopaminergic tracts in the control over LH.

Adult

[Comparison between hypo- and hyperglucidic diets on protein sparing in major visceral surgery (author's transl)].

The authors compare the protein sparing effect of two diets, exclusively intravenous, including the same protein intake, but a different caloric intake, 21 calories/gm nitrogen for diet "A" (20 cases); 138 calories/gm nitrogen for diet "B" (20 cases). This has been observed during the six post-operative days of major visceral surgery: oesophagectomy, total gastrectomy, colic or rectocolic exeresis, sequestrectomy for acute pancreatitis, lots having been drawn for the diets. Daily nitrogen balances have been made and plasmatic and urinary levels of amino-acids have been measured before surgery and on the third and fifth post-operative days. Statistical exploitation is done by variance analysis (linear model of three factors) with a 99% confidence ratio: 1) Patient factor has no influence whatsoever on cumulative nitrogen balance. 2) Time factor arises only on the fourth post-operative day and only in the hypocaloric diet, leading to catabolism. 3) Metabolic condition is determinant. On no cancerous disease, superiority of hypercaloric diet is well demonstrated. On cancerous disease, nitrogen loss is only significantly different on 4th and 5th post-operative day: hypercaloric diet gives a better nitrogen balance.

Adult

Progesterone metabolism in newborn rat heart cell cultures.

Progesterone metabolism was studied in newborn rat heart cell cultures. The following enzymatic activities have been identified: 20 alpha-hydroxysteroid dehydrogenase, 3 alpha- and 5 alpha-hydroxysteroid oxidoreductases, and 6 alpha-hydroxylate. These activities are independent of sex and are probably related to the neonatal origin of the cells.

20-Hydroxysteroid Dehydrogenases

Gas-liquid chromatography of isobutyl ester, N(O)-heptafluorobutyrate derivatives of amino acids on a glass capillary column for quantitative separation in clinical biology.

A gas chromatographic method adapted to routine analysis has been developed for quantitative separation on glass capillary columns for free proteic and other known amino acids normally or abnormally found in physiological fluids. The procedure involves ion-exchange chromatography and isobutyl ester, N(O)-heptafluorobutyrate derivatization of free plasma and urine amino acid samples. Derivatized components were ascertained by combined gas chromatography-mass spectrometry. The use of glass for the capillary column is mandatory to achieve qualitative and quantitative analysis of the known occurring amino acids in urine and small plasma samples. Quantitative analysis of several types of human amino acid disorders are presented.

Amino Acid Metabolism, Inborn Errors