PubMed Health⌕ Search

Biomedical subjects

J Guillon

Publications and source records attributed to J Guillon.

At least 19 recordsLinked to original sources
PubMed2001

Synthesis and preliminary behavioural evaluation in mice of new 3-aryl-3-pyrrol-1-ylpropanamides, analogues of FGIN-1-27 and FGIN-1-43.

The 2-aryl-3-indoleacetamides FGIN-1-27 and FGIN-1-43 have already been characterized in-vitro as potent and specific ligands for the mitochondrial DBI receptor. This affinity was associated with psychotropic properties in several rodent behavioural tasks (in particular anxiolytic action) via enhancement of GABA transmission through neurosteroid production. The synthesis of new 3-aryl-3-pyrrol-1-ylpropanamides 1a-i, analogues of FGIN-1-27 and FGIN-1-43, is described in four steps starting from the corresponding arylaldehydes. Preliminary evaluation of these compounds in behavioural studies (spontaneous locomotor activity and anxiolytic activity) in mice was also undertaken.

Animals↗
PubMed2000

Synthesis of cone, partial-cone, and 1,3-alternate 25, 27-Bis

The preparation of 25,27-bis[1-(2-ethyl)hexyl]- and 25, 27-bis[1-(2-tert-butoxy)ethyl]calix[4]arene-crown-6 combining one polyether crown-6 and one alkylchain O-attached on each side of a calix[4]arene in the cone, partial-cone, and 1,3-alternate conformations are reported. The control over 25, 27-bisalkylcalix[4]arene-crown-6 conformation via varying specific reaction conditions was studied. The series of calix[4]arenes have been prepared by two routes, which differ in the order in which the alkyl or polyether groups were introduced. Moreover, methods have been developed to selectively prepare the cone and partial-cone conformers by using an appropriate base in the alkylation reactions. The conformations of these new derivatives have been probed by (1)H NMR analysis and X-ray crystallography. The (1)H and (13)C NMR spectra of 25,27-bis[1-(2-ethyl)hexyl]calix[4]arene-crown-6, 1, 3-alternate 1, cone 2, and partial-cone 3 are also discussed.

Journal Article↗
PubMed2000

New aromatase inhibitors. Synthesis and biological activity of aryl-substituted pyrrolizine and indolizine derivatives.

We report herein the design and the synthesis of some aryl-substituted pyrrolizine and indolizine derivatives, on the basis of a hypothetical pharmacophore structure designed to fit the catalytic site of the human cytochrome P450 aromatase. The in vitro biological evaluation of these compounds allowed us to point out two new potent non-steroidal aromatase inhibitors, MR 20494 and MR 20492, with IC50 values in the range of 0.1 microM.

Aromatase Inhibitors↗
PubMed2000

Synthesis of new 2-(aminomethyl)-4-phenylpyrrolo[1,2-a]-quinoxalines and their preliminary in-vivo central dopamine antagonist activity evaluation in mice.

In the search for antipsychotic agents that are not associated with extrapyramidal side effects, efforts have been focused on finding selective D4-receptor antagonists and investigating their pharmacology. Our laboratory has developed a synthesis program for new pyrroloquinoxalines with therapeutic potential. We have described the synthesis of some new pyrroloquinoxalines with substituted arylpiperazino or aryltetrahydropyrido chain at position 3 of the quinoxaline ring (2-(4-phenylpiperazin-1-ylmethyl)-4-phenylpyrrolo[1,2-a]quinoxalinium oxalate (3a), 2-[4-(2-methoxyphenyl)piperazin-1-ylmethyl]-4-phenylpyrrolo[1,2-a]quinoxalinium oxalate (3b), 2-[4-(3-trifluoromethylphenyl)piperazin-1-ylmethyl]-4-phenylpyrrolo[1,2-a]quinoxalinium oxalate (3c), 2-[4-(4-chlorophenyl)piperazin-1-ylmethyl]-4-phenylpyrrolo[1,2-a]quinoxalinium oxalate (3d), 2-(4-pyridin-2-ylpiperazin-1-ylmethyl)-4-phenylpyrrolo[1,2-a]quinoxalinium oxalate (3e), and 2-(4-phenyl1,2,3,6-tetrahydropyridin-1-ylmethyl)-4-phenylpyrrolo[1,2-a]quinoxalinium oxalate (3f)). A preliminary pharmacological study of these products was conducted using climbing behaviour induced by apomorphine (2.5 mg kg(-1), s.c.) in mice. The derivatives were administered intraperitoneally 30 min before apomorphine. Haloperidol, chlorpromazine and clozapine were used as references. Among this series, 3b, 3c and 3f revealed a central dopamine antagonist activity. The most active derivative was 3b, which exhibited a profile relatively close to clozapine.

Animals↗
PubMed1998

Design and synthesis of a new type of non steroidal human aromatase inhibitors.

The structure-activity relationship study of one of recently described aromatase inhibitors, compound 1 (MR20814), allowed us to design some related derivatives as potential new inhibitors. Among those we synthesized, chlorophenylpyridylmethylenetetrahydroindolizinone 5 (MR20492) exhibited in vitro a ten-fold higher inhibition of the enzyme (IC50 = 0.2 +/- 0.0 microM and Ki = 10.3 +/- 3.3 nM).

Aromatase Inhibitors↗
PubMed1990

Effect of long-acting somatostatin analog (SMS 201-995) on high glomerular filtration rate in insulin dependent diabetic patients.

Increased glomerular filtration rate (GFR) is considered to be a determinant factor in the pathogeny of diabetic nephropathy. In this study we analyzed the effect of a long-acting somatostatin analog (SMS 201-995) on high GFR in type I diabetes patients. Five subjects were involved in a cross-over double blind study. All the patients had a high GFR (205 +/- 18 ml/min/1.73 m2). They were randomly submitted to a 10-hour night i.v. infusion of SMS 201-995 at a rate of 8 g/min and placebo. GFR was measured using a blood 99mTc-DTPA decay curve during the last hour of infusion. After 10-hour SMS 201-995 treatment, no statistical change was observed in GFR. However, a slight decrease was noted in four of the five subjects (183.07 +/- 22.31 vs 202.83 +/- 13.23 ml/min/1.73 m2). GFR was higher only for the patient who presented with a mild hypoglycemic reaction during the infusion, which may increase glomerular filtration by itself. All the other parameters measured remained unchanged.

Adult↗
PubMed1987

[Microalbuminuria is not a marker of diabetic retinopathy].

Microalbuminuria is considered a good predictor of diabetic nephropathy. In this study over 50% of patients with retinopathy, whatever its severity, did not show microalbuminuria. However, among patients with microalbuminuria, the percentage of retinopathy was significantly increased (75%). It is concluded that with the exception of nephropathy, microalbuminuria is not a good parameter for the detection of other microangiopathic complications of diabetes.

Adult↗
PubMed1987

[Neurotoxicity of mitotane therapy of adrenocortical carcinoma (5 cases) and Cushing's syndrome (7 cases)].

Twelve patients were treated with op'DDD over a 9-year period. All presented with mild neurological symptoms, and half of them had major complications. There was no relation between the occurrence of these symptoms and the dose or duration of op'DDD therapy. The mechanisms of this neurological toxicity, both central and peripheral, are not well known, but they appear to be similar to those of certain op'DDD-related chemicals used in industry.

Adolescent↗
PubMed1986

[Methodological problems in the determination of microalbuminuria].

We have performed 7 different urinary collections to assess albumin excretion rate in insulin-dependent diabetics. The night and the 24 hours urine collections were more accepted than the others. For albumin excretion rate there was no correlation among the different collections. So, the albumin excretion rate must be done always on the same sample for one patient and be repeated to confirm pathological values.

Adult↗
PubMed1985

[Radioimmunoassay of urinary albumin: early indicator of diabetic nephropathy?].

Microalbuminuria is now considered a good biological marker predictive of diabetic nephropathy. The degree of microalbuminuria was determined by radioimmunoassay in 23 controls and 50 insulin-dependent patients with poor control of glycaemia. Higher levels were found in diabetics, whatever the duration of the disease. At the moment, this difference, which is reversible with good metabolic control, can be explained by blood glucose balance. Several authors have established the existence of a microalbuminuria threshold predictive of nephropathy, but its level is controversial, chiefly on account of the urine collection methods.

Adolescent↗
PubMed1985

[Should the assay of serum free thyroxine and triiodothyronine replace the other methods of evaluating thyroid function?].

Total T4, total T3, free T4 and free T3 were measured at the same time in 633 subjects. These subjects were classified according to the clinic state and the hormonal results in 426 euthyroid, 145 hyperthyroid and 62 hypothyroid cases. The results permitted to define the sensitivity, specificity and predictive value of the different tests. When each measure was considered alone, free T4 was the most useful test for all the hormonal states. In association, FT4 + FT3 is more useful than T3T + T4T for all the diagnostic parameters and for all the clinical situations. To measure FT4 with an adequate kit appears to be in 1985 the key method for evaluating the thyroïd function. To associate FT3 is useful in some difficult cases.

Humans↗
PubMed1985

Pharmacokinetics of fosfomycin in hemodialyzed patients.

The pharmacokinetics of fosfomycin, an original antimicrobial agent, were investigated in 11 voluntary hemodialyzed patients. Fosfomycin, 2 g, was administered intravenously, 15 minutes before hemodialysis began in group 1 (6 patients), and just after hemodialysis in group 2 (6 patients). Blood samples were collected during 8 hours (group 1) and during 44 hours (group 2). Antibiotic concentrations were determined microbiologically. In group 1, half-life was 4.2 +/- 0.27 hours, total clearance 65.1 +/- 7.1 ml/mn and clearance by hemodialyzer 103 +/- 10 ml/mn. In group 2 plasma levels were 60 mg/l at the 44th hour and half-life was 48.8 +/- 17.5 hours. These results suggest that fosfomycin is actively eliminated by the hemodialyzer in group 1, and largely retained between two dialysis sessions in group 2. As for therapy, intravenous administration of 2 g after dialysis and further administration after each succeeding session are proposed.

Adult↗
PubMed1985

[Alcohol and metabolic disorders].

Alcohol can cause disturbance in the main metabolic pathways. Alterations of glycoregulation are particularly frequent in chronic alcoholics as well as disorders of lipoprotein. Other biochemical abnormalities affect protein, vitamins and trace elements. But it is often difficult to decide the extent these abnormalities are the result of the direct toxic effect of alcohol or secondary to organ damage.

Acidosis↗
PubMed1984

[Prevention of poliomyelitis: live or killed vaccine? Remarks apropos of 2 cases of poliomyelitis].

The attenuated poliovirus vaccine is remarkably effective in preventing the disease but its innocuity has always been questioned. It seems to be responsible for occasional cases of spinal paralysis occurring in developed countries where poliomyelitis has virtually been eradicated. The authors report two cases of acute anterior poliomyelitis in young adults, in which the poliovirus recovered from the faeces might have been of vaccinal origin. Virological techniques do not always characterize the strains isolated, nor distinguish between a vaccinal mutant and a wild poliovirus. These data, together with previously published cases, have prompted the authors to discuss whether the use of a live poliovaccine is justified.

Adult↗