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F Tabuteau

Publications and source records attributed to F Tabuteau.

At least 19 recordsLinked to original sources

Whole blood serotonin and plasma beta-endorphin in autistic probands and their first-degree relatives.

BACKGROUND: Whole blood serotonin (5-HT) and C-terminally directed beta-endorphin protein immunoreactivity (C-ter-beta-EP-ir) are known to be elevated in autistic subjects and might be possible markers of genetic liability to autism. This study thus investigates the familial aggregation of 5-HT and of C-ter-beta-EP-ir levels in first degree relatives of autistic probands. METHODS: In a sample of 62 autistic subjects and 122 of their first-degree relatives, compared to age and sex-matched controls, we measured 5-HT by radioenzymology and C-ter-beta-EP-ir by radioimmunoassay. RESULTS: We confirm the previously reported familiality of hyperserotoninemia in autism as mothers (51%), fathers (45%) and siblings (87%) have elevated levels of 5-HT, and we reveal presence of elevated levels of C-ter-beta-EP-ir in mothers (53%) of autistic subjects. CONCLUSIONS: Familial aggregation of quantitative variables, such as concentration of neurotransmitters, within unaffected relative could serve as an intermediate phenotype and might thus help the search of genetic susceptibility factors in autism.

Adolescent↗

Low-dose naltrexone effects on plasma chemistries and clinical symptoms in autism: a double-blind, placebo-controlled study.

The effect of month-long naltrexone (NTX) treatment at a daily oral dose of 0.5 mg/kg/day was contrasted with placebo (PLC) in a double-blind study with conjoint clinical and biochemical evaluations of therapeutic effects. Modest clinical benefits were achieved with both PLC and NTX, with marginally better overall results following NTX, and degree of improvement appeared to be related to plasma chemical profiles. Massively elevated levels of beta-endorphin were observed in all children with assays using C-terminal antibody but not with an N-terminal antibody assay. In addition, 70% of the children exhibited abnormally low levels of adrenocorticotropic hormone, and smaller subsets exhibited elevated norepinephrine (60%), arginine-vasopressin (50%), and serotonin (20%). The best clinical responders exhibited the clearest normalization of the elevated plasma chemistries, especially in C-terminal-beta-endorphin and serotonin. There was some evidence of therapeutic carry-over effects in both clinical and biochemical measures in those children who received NTX before PLC. The results suggest that NTX only benefits a subgroup of autistic children, who may be identified by the presence of certain plasma abnormalities. These results suggest a possible linkage between abnormal plasma chemistries, especially those related to the pro-opiomelanocortin system, and autistic symptoms.

Adolescent↗

Helicobacter pylori infection: physiopathologic implication of N alpha-methyl histamine.

BACKGROUND/AIMS: In the gastric mucosa of Helicobacter pylori-infected subjects, we previously detected N alpha-methyl histamine (N alpha-MeHA), a minor catabolite of histamine and a potent agonist of histamine H3 receptors. The origin of N alpha-MeHA and its effects on gastric histamine and somatostatin in infected subjects were investigated. METHODS: Ten noninfected patients and 13 patients with intense colonization were compared. N alpha-MeHA content and its synthetic enzyme activity, N alpha-histamine methyltransferase, binding of [3H]N alpha-MeHA, histamine and somatostatin contents, and histidine decarboxylase activity were assayed in antral and fundic biopsy specimens and in cultured H. pylori strains. RESULTS: Gastric histamine and somatostatin contents as well as histidine decarboxylase activity were decreased in infected patients and were restored to normal after antimicrobial treatment. Both N alpha-MeHA and N alpha-histamine methyltransferase activity were present in the mucosa of infected patients and in cultured strains and were very low in noninfected patients or after eradication of H. pylori. [3H]N alpha-MeHA bound to gastric mucosa but not to cultured strains. The [3H]N alpha-MeHA specific binding sites were characterized as H3 receptors. The amount of bound [3H]N alpha-MeHA seemed correlated positively with somatostatin content and histidine decarboxylase activity and negatively with N alpha-MeHA content and N alpha-histamine methyltransferase activity. CONCLUSIONS: H. pylori is the main source of gastric N alpha-MeHA that may lower histidine decarboxylase activity and somatostatin content through H3 receptors.

Gastric Mucosa↗

Difference between plasma N- and C-terminally directed beta-endorphin immunoreactivity in infantile autism.

OBJECTIVE: The authors investigated whether there is excessive opioid activity in infantile autism by measuring plasma beta-endorphin in patients with autism compared with patients who had Rett's syndrome and normal comparison subjects. METHODS: Radioimmunoassays for beta-endorphin using C-terminally and N-terminally directed antisera were applied to plasma samples from 67 children who met both DSM-III-R and ICD-10 diagnostic criteria for infantile autism, 22 girls with Rett's syndrome, and 67 normal children matched in age and sex with the children with autism. RESULTS: Median N-terminally directed beta-endorphin immunoreactivity appeared to be slightly lower in subjects with autism (7 pg/ml) and clearly higher in the girls with Rett's syndrome (40 pg/ml) than in the comparison subjects (9 pg/ml). Median C-terminally directed beta-endorphin immunoreactivity was higher in the girls with Rett's syndrome (35 pg/ml) and much higher in patients with autism (70 pg/ml) than in comparison subjects (8 pg/ml). CONCLUSIONS: These findings demonstrate the existence of a wide discrepancy between C- and N-terminally directed beta-endorphin immunoreactivity among children with autism. Despite the fact that the nature of the antigen recognized in the plasma of autistic children by the C-terminally directed anti-beta-endorphin serum remains to be characterized, the difference between C- and N-terminally directed beta-endorphin immunoreactivity might suggest an abnormal processing of the pro-opiomelanocortin gene in infantile autism.

Adolescent↗

Metabolic effects of combined cyproterone acetate and percutaneous 17 beta oestradiol after six and twelve months therapy in 61 patients.

The metabolic effects of combined cyproterone acetate (50 mg) and percutaneous 17 beta oestradiol were studied during one year in 61 patients admitted for hyperandrogenia. Before treatment and at 6 and 12 months the following tests were performed: oral glucose tolerance test (OGTT) with insulinemia dosage, determination of total cholesterol, LDL, VLDL and HDL fractions, triglycerids, A1 and B apoproteins, liver function tests: bilirubinemia, alkaline phosphatases, transaminases and gamma glutamyl transferases. The patients' mean age was 27.0 +/- 6.8 years, the body mass index was 22.4 +/- 3.5 kg/m2. After one year of treatment the body mass index was not modified. Blood glucose slightly increased during OGTT; at 6 months this was significant at +30 minutes, at 12 months at +30, +60 and +90 minutes (P less than 0.05). There was no variation in insulinemia during OGTT. Total cholesterol decreased significantly at 6 and 12 months (P less than 0.001), this was associated with a decrease in HDL cholesterol, but without modification of the LDL + VLDL/HDL ratio. Decrease in HDL cholesterol was associated with a significant decrease in A1 apoproteins. No change in triglycerids and in liver function tests was observed at either date. In conclusion the metabolic effects of this association are described. These effects are minimal compared to those observed with cyproterone acetate and ethinyl oestradiol association in the literature. However, attention should be drawn to the possibility of glucose intolerance and decrease in HDL cholesterol and A1 apoproteins.

Adult↗

Serotonin metabolism and other biochemical parameters in infantile autism. A controlled study of 22 autistic children.

The serotonin metabolism was extensively studied in 22 couples of autistic children and age- and sex-matched controls. Histamine, calcium, and uric acid were also measured in urine and whole blood or plasma. Autistics and controls did not differ in histamine, and only minor changes were noticed in calcium content. According to previous reports, serotonin levels were often, but not always, elevated in the blood of autistic children. Based on data including urinary serotonin and 5-hydroxyindoleacetic acid, platelet serotonin uptake and efflux, platelet monoamine oxidase and glutathione peroxidase activities, and uric acid and plasma tryptophan, the origin(s) of such hyperserotonemia in autism appear(s) to be of metabolic origin, i.e., a decreased catabolism and/or an increased biosynthesis of serotonin.

Adolescent↗

Serum inorganic sulphate: quantitation by a new radiochemical method.

A new procedure for serum inorganic sulphate determination is described. The method is simple, accurate and highly reproducible. It is based on radioisotopic dilution of 35S-sulphate by protein-free, phosphate-free serum. The decrease in initial 35S-sulphate specific activity (corresponding to added serum sulphate) is determined in the supernatant after partial precipitation of sulphate by barium ion. Serum sulphate is computed thereafter from a standard curve. Recovery of added sulphate from dialysed or undialysed serum was 100%. The intra- and interassay coefficients of variation were 3.5% and 4.1%, respectively. The serum sulphate concentration measured by this method in 93 normal subjects was 400 +/- 90 mumol/l (mean +/- SD), which agreed with the values reported in the literature. Serum sulphate did not correlate with sex (p greater than 0.40, n = 93), but a significant correlation with age was observed (r = 0.25, p less than 0.02, n = 93).

Adolescent↗

[Effects of nifedipine on carbohydrate metabolism in the non-insulin dependent diabetic].

The aim of this prospective, randomized, double-blind, placebo controlled study was to investigate the effect of nifedipine on carbohydrate metabolism in diabetic patients after a 3-day and a 3-month course of treatment. Sixteen non obese, well controlled non-insulin dependent diabetics, (HbA1 less than 10%), with moderate untreated hypertension were divided in two groups: nifedipine (group N, 8 patients) and placebo (group P, 8 patients). An oral glucose tolerance test (OGTT, 75 g glucose) and an arginine infusion were performed before, after a 3-day, and a 3-month course, either of nifedipine 30 mg/D or placebo. Blood samples obtained during OGTT were assayed for glucose and insulin, and during arginine infusion for insulin, glucagon and growth hormone. The differences between basal and peak values during tests were compared between both groups before and after treatment using Wilcoxon's rank sum test. Neither acute nor chronic administration of nifedipine or placebo modified the glucose tolerance. However, basal insulin levels were reduced by 3 month-administration of nifedipine (from 19 +/- 2 micromicrons/ml to 10 +/- 1 micromicrons/ml, p = 0,01). Otherwise the basal and peak hormonal values during tests were not significantly affected by nifedipine either at the start of after 3 months of treatment. These results suggest that nifedipine, when given in standard dosage for 3 months, has minor effects on carbohydrate metabolism in non-insulin dependent diabetic patients.

Adult↗

The diffuse neuroendocrine (APUD) system.

The bulk of experimental evidence indicates that the APUD series of cells is a distinct system based upon common pathophysiological features. The diffuse nature of this system with elements in the central and peripheral nervous system suggests a more complex interaction of the body's homeostasis than has been established. It is probable that as radioimmunological and radioenzymatic assays become more widely available and standardized, other apudomas will be described. Finally, an understanding of the APUD concept, with its peculiar pluripotential for the production of biogenic amines and peptides, the multicentric nature of the disease and the possibility of multiple cell involvement, is of key importance in managing patients. Studies of the apudomas will also advance the understanding of the normal physiologic interrelationships of the APUD cells.

APUD Cells↗

Percutaneous absorption of 5 alpha-dihydrotestosterone in man. II. Percutaneous administration of 5 alpha-dihydrotestosterone in hypogonadal men with idiopathic haemochromatosis; clinical, metabolic and hormonal effectiveness.

The particularities of percutaneous absorption of a natural androgen, 5 alpha-dihydrotestosterone, were evaluated in substitutive androgen therapy in masculine hypogonadism. Nine men presenting idiopathic haemochromatosis complicated by severe hypogonadism were treated with percutaneous administration of 5 alpha-dihydrotestosterone (125 mg/day) for 5 months. Plasma levels of 5 alpha-dihydrotestosterone and 5 alpha-androstane-3 alpha, 17 beta-diol are greatly increased by treatment (from 0.86 to 18.39 nmol/l and 0.16 to 3.40 nmol/l, respectively). There is no modification of testosterone and oestradiol-17 beta. Double blind study demonstrated the direct stimulating effect of 5 alpha-dihydrotestosterone on sexual behaviour and psychism. Hepatic and metabolic tolerance was excellent in these patients, despite the preceding deleterious effects of the iron excess. The percutaneous route is original, practical and improves the androgen therapy of hypogonadism in men.

Adult↗

Physiological and pathological variations in saliva cortisol.

A radioimmunological method for measuring saliva cortisol was worked out. It includes one extraction and one radiocompetitive reaction with an anticortisol 3-CMO:BSA immunoserum. Frequent values for saliva cortisol were determined in various physiological and pathological conditions and compared to plasma cortisol values. In adult men, the mean concentrations at 8 a.m. and midnight were respectively 14.50 +/- 7.10 and 1.40 +/- 1.21 nmol/l (mean +/- SD). In untreated women, plasma and saliva cortisol levels were not significantly different from those measured in women taking estroprogestative drugs or in pregnant women. Following stimulation by synthetic beta 1-24 ACTH (Synacthen), the saliva cortisol determined 90 min after the 8 a.m. sampling rose by over 500% whereas plasma cortisol only rose by 120%. Similarly the drop in 8 a.m. cortisol, which followed midnight administration of 1 mg of dexamethasone was larger for saliva than for plasma cortisol. In patients with adrenal hyperactivity the circadian rhythm disappeared from saliva cortisol and patients with deficient adrenal activity displayed drastically reduced levels for saliva cortisol. Saliva cortisol seems thus to be more helpful to diagnosis than plasma cortisol.

Adolescent↗

Post-menopausal concentrations of plasma oestradiol, oestrone, FSH and LH and of total urinary oestradiol and oestrone after a single sublingual dose of oestradiol-17 beta.

We report the effects of sublingual absorption of a single dose (0.5 mg) of oestradiol-17 beta (E2) in 8 post-menopausal women, on plasma E2 and oestrone (E1), urine elimination of total E2 + E1 and on plasma FSH and LH. The results show that sublingual absorption of E2 occurs and that plasma concentrations of E2 obtained (between 133.2 to 320 pmol/l) in this way were higher than those obtained after percutaneous absorption of a single dose (3 mg) of E2. The ratio E1/E2 in plasma is close to that of pre-menopausal women.

Absorption↗

[Effect of long-term administration of clonidine on growth hormone secretion in hypertensive diabetics].

The anti-hypertensive effect of clonidine is closely related to its central alpha-agonist action. In acute administration, the drug provokes a significant increase in the plasma concentrations of growth hormone (GH). In chronic administration, the effects of clonidine on GH secretion are not well documented. Clonidine was administered at a daily dose of 0,15 to 0,30 mg to 10 non-obese diabetic hypertensive male subjects for at least 3 months. Blood glucose and GH plasma concentrations were determined 15 times during the 24-hour cycle. Blood glucose and GH values recorded before the intake and after stopping the drug, in the basal state, after meals, after measured muscular exercise and during the first stage of sleep could be superimposed when on and off clonidine. The effects of prolonged administration of clonidine on GH secretion thus differ markedly from the effects of acute administration as in non diabetic subjects. The long-term use of clonidine does not induce a chronic increase of GH plasma concentrations which might worsen the evolution of the diabetic microangiopathy.

Adult↗

[Study of the reference values and nyctohemeral cycle of serum iron].

Marked variations in the same individual of serum iron levels may be due to a circadian rhythm. We determined the reference values of serum iron in a population of blood donors who had no blood disease. The very wide reference interval found (0.47 to 1.75 mg/l in man and 0.36 to 1.66 mg/l in women) was due to physiological variations rather than analytical variations. We also demonstrated in individuals with a normal life rhythm, a circadian rhythm for iron with maximal levels in the morning (8 to 12) and minimal levels in the evening (8 p.m. to midnight) the ratio of these levels is usually between 1.5 and 2, but may reach much higher figures. On the other hand, the total fixation capacity varies little over 24 hours. In night workers, one may note a displacement of the cycle with a maximum towards 8 p.m. a minimum at 8 a.m. In diabetics, the circadian rhythm exists but with a lower amplitued than in healthy subjects. In a few cases a hemochromatosis, one may note disappearance of the cycle.

Adult↗

Plasma histamine levels and kinetics in chronic hemodialysis patients.

Pruritus is frequently observed in hemodialyzed patients; its etiology seems to be multifactorial. Increased plasma histamine levels have been reported in chronic renal failure. As histamine is a potent inducer of pruritus. The authors investigated its concentrations and kinetics in plasma of stable hemodialyzed patients.

Adult↗