Search PubMed⌕ Search

Biomedical subjects

P Simon

Publications and source records attributed to P Simon.

At least 361 records · Page 20Linked to original sources
PubMed1987

The automated Tail Suspension Test: a computerized device which differentiates psychotropic drugs.

1. Mice when suspended by the tail will alternate between active attempts to escape and immobility. Immobility like that measured in the behavioral despair test is reduced by a wide variety of antidepressant agents. 2. The present paper describes a computerized version of this test (ITEMATIC-TST) which in addition to recording immobility measures the power of the movements. 3. Various tricyclic (amitriptyline, desipramine, imipramine), MAOI (clorgyline, moclobemide, nialamide, pargyline, toloxatone) and atypical antidepressants (bupropion, citalopram, indalpine, mianserin, nomifensine, viloxazine) were tested and compared with psychostimulants (d-amphetamine, caffeine), neuroleptics (chlorpromazine, haloperidol, sulpiride), anxiolytics (clobazam, diazepam) and agents acting on the cholinergic system (atropine, oxotremorine). 4. All antidepressants decreased the duration of immobility and most increased the power of movements. 5. The psychostimulants also decreased immobility but only amphetamine increased the power of movements. 6. Neuroleptics increased immobility without affecting the power of movements, whereas anxiolytics increased immobility but decreased the power of movements. 7. Atropine had a profile similar to antidepressants whereas oxotremorine tended to have opposite effects. 8. The results suggest that the automated test system with its two parameters is not only sensitive to antidepressants but could also be useful for generating activity profiles for different kinds of psychotropic agent.

Animals↗
PubMed1987

The effect of monoamine oxidase inhibitors compared with classical tricyclic antidepressants on learned helplessness paradigm.

The present study investigated the effect of monoamine oxidase inhibitors, nialamide which is a non specific monoamine oxidase inhibitor (MAOI), toloxatone which is a A type MAOI and L-deprenyl which is a B type MAOI compared with classical tricyclic antidepressants (clomipramine, desipramine and imipramine), on the escape deficit induced by inescapable shocks (learned helplessness paradigm). Rats were first exposed to inescapable shock pretreatment (60 shocks, 15 sec duration, 0.8 mA, every minute + 15 sec) and 48 h later, shuttle box training (30 trials/day, 15 min.) was initiated in order to evaluate interference effect. Rats with inescapable shocks exhibited escape and avoidance deficits when tested for subsequent responding in a shuttle-box. Daily i.p. injections of nialamide (8 and 16 mg/kg), toloxatone (16 and 32 mg/kg), L-deprenyl (32 and 64 mg/kg) and tricyclic antidepressants (clomipramine: 16 and 32 mg/kg, desipramine: 16 and 24 mg/kg, imipramine: 16 and 32 mg/kg) eliminated escape deficits. In rat exposed to inescapable shocks and treated with L-deprenyl (16 mg/kg/day), nialamide (32 mg/kg/day) or toloxatone (64 mg/kg/day), avoidance responses are significantly increased as compared with non drugged rats preexposed to inescapable shocks. These data extend previous results bearing on the similarity of action of MAOI and tricyclic antidepressants in learned helplessness paradigm (Sherman et al., 1982) and are in agreement with data obtained in other animal models of depression.

Animals↗
PubMed1987

Pharmacokinetics and renal elimination of desferrioxamine and ferrioxamine in healthy subjects and patients with haemochromatosis.

1 Desferrioxamine mesylate (DM) (10 mg kg-1 = 15.24 mumol kg-1) was given by intramuscular injection to five healthy subjects and to six patients with haemochromatosis, after informed consent. 2 Desferrioxamine (DFA), ferrioxamine (FeA), aluminoxamine (AlA), aluminium (Al) and iron (Fe) were measured in plasma, before and 10, 20, 30, 60 min and 2, 4, 6, 8, 12 h after DM injection and in urine collected over a 6 h period the day before and the day of administration. 3 The predominant form in plasma from control subjects was DFA whereas FeA predominated in plasma from patients. In controls, rapid and slow phases of decline in plasma DFA concentrations were found, with half-lives of 1.0 h and 6.1 h, respectively. In the patients, only a single phase of decline was observed, with a half-life of 5.6 h. Total clearances of DFA were 296 ml h-1 kg-1 in controls and 239 ml h-1 kg-1 in patients. 4 The amount of FeA eliminated in urine during 6 h was significantly lower in controls (8.0 +/- 4.6 mumol) than in patients (129.2 +/- 40.0 mumol), with respective renal clearances estimated over 6 h of 516 ml h-1 kg-1 and 1,716 ml h-1 kg-1. DFA elimination was similar in both groups and its renal clearance estimated over 6 h was 91 ml h-1 kg-1 in controls and 85 ml h-1 kg-1 in patients. 5 Since there was no overlap in the 1 h DFA/FeA plasma ratio between controls and patients, this might be useful as an index of iron overload.

Adult↗
PubMed1987

Effects of melatonin implantation on spermatogenesis, the moulting cycle and plasma concentrations of melatonin, LH, prolactin and testosterone in the male blue fox (Alopex lagopus).

Melatonin administration to male blue foxes from August for 1 year resulted in profound changes in the testicular and furring cycles. The control animals underwent 5-fold seasonal changes in testicular volume, with maximal values in March and lowest volumes in August. In contrast, melatonin treatment allowed normal redevelopment of the testes and growth of the winter coat during the autumn but prevented testicular regression and the moult to a summer coat the following spring. At castration in August, 88% of the tubular sections in the testes of the controls contained spermatogonia as the only germinal cell type, whereas in the treated animals 56-79% of sections contained spermatids or even spermatozoa. Semen collection from a treated male in early August produced spermatozoa with normal density and motility. Measurement of plasma prolactin concentrations revealed that the spring rise in plasma prolactin values (from basal levels of 1.6-5.4 ng/ml to peak values of 4.1-18.3 ng/ml) was prevented; values in the treated animals ranged during the year from 1.8 to 6.3 ng/ml. Individual variations in plasma LH concentrations masked any seasonal variations in LH release in response to LHRH stimulation, but the testosterone response to LH release after LHRH stimulation was significantly higher after the mating season in the treated animals, indicating that testicular testosterone production was maintained longer than in the controls. The treated animals retained a winter coat, of varied quality and maturity, until the end of the study in August.

Animals↗
PubMed1987

Sexual development in the immature male blue fox (Alopex lagopus), investigated by testicular histology, DNA flow cytometry and measurement of plasma FSH, LH, testosterone and soluble testicular Mn2+-dependent adenylate cyclase activity.

Testicular weight in young male blue foxes increased steadily from 12 weeks of age (0.4-0.7 g) to reach peak values at the time of the mating season in March-April (5.2-6.6 g), before declining rapidly during May to low values in August at 63 weeks of age (1.3-1.6 g). Primary spermatocytes were found in the spermatogenic epithelium at 20 weeks of age and by late December (29 weeks of age) elongated spermatids were seen. There was a good correlation between the seasonal variations in the presence of germ cell types assessed by quantitative analysis of testicular histology and the variations in numbers of haploid, diploid and tetraploid cells measured by DNA flow cytometry: no haploid cells were found before the end of November and peak numbers were observed in March. Plasma FSH concentrations were increased from December onwards (with the exception of April). There were no clearcut seasonal variations in plasma LH concentrations although values were consistently lower in April. Testosterone concentrations were low for most of the year but increased from the end of January to the middle of April. There was no detectable seasonal variation in LH release in response to LHRH injection, and no typical pattern in plasma FSH concentrations during the first 100 min after injection. Plasma testosterone concentrations after LHRH injection rose gradually during testicular development. There were large seasonal variations in soluble Mn2+-dependent adenylate cyclase activity in the testis, that paralleled the changes in testicular weight and haploid cell content. Values were low until December and reached a peak at the time of the mating season before falling to basal levels again by June. The results suggest that immature male blue foxes reach full testicular development (indistinguishable from that of older animals) by the first mating season after birth at, an age of about 40 weeks.

Adenylyl Cyclases↗
PubMed1987

Preliminary studies of the effects of bromocriptine on testicular regression and the spring moult in a seasonal breeder, the male blue fox (Alopex lagopus).

Bromocriptine administration in the form of slow-release injections to male blue foxes during March-May abolished the normal spring rise in plasma prolactin concentrations seen in May and June. The spring moult was prevented and the treated animals retained a winter coat of varied quality and maturity until the end of the study in August. Plasma testosterone concentrations fell normally from March until August. Testicular regression was, however, delayed, although there were individual variations in response. Estimation by DNA flow cytometry in early July of the relative numbers of haploid, diploid and tetraploid cells in the testis showed that, in the treated animals, 74-80% of the cells were haploid (maturing germinal cells), 4-6% tetraploid (mainly primary spermatocytes) and the rest diploid cells (somatic cells and the remaining germinal cell types). In the control males, however, no haploid cells were detected and the majority of cells were diploid (93-99%). At castration in August, histological examination revealed various stages of testicular regression in the treated and control animals.

Animals↗
PubMed1987

[Epidemiology of terminal renal insufficiency treated by dialysis and therapeutic options in a population of 400,000 inhabitants (1975-1986)].

Since January, 1, 1976, epidemiologic study of renal diseases has been leading in a French rural area of 400,000 inhabitants located in north coast of Britanny. Annual incidence of end stage renal failure (ESRF) treated by dialysis increased of 25% when two consecutive periods of five years each were compared: A (1976-1980) 46 per 10(6) inhabitants, B (1981-1985) 62 per 10(6) inhabitants. In 1986, the progression was confirmed: 96 per 10(6). At the time of the beginning of dialysis treatment, mean age (+/- SD) was not different between two periods: 53 +/- 17 yrs (A) vs 51 +/- 17 yrs (B) but it increased in 1986: 61 +/- 14 yrs. Sex ratio (M/F) progressed from 1 (A) to 1.75 (B). The study of causes of ESRF showed a net increase of secondary renal diseases (diabetes, amyloidosis), interstitial nephropathies due to obstructive uropathy (lithiasis) and drugs. For the period B, 91% of primary glomerulonephritis reaching ESRF had had renal biopsy. Idiopathic IgA nephropathy was the first cause of ESRF (13.7%, 0.85 pts/100,000) before diabetes (12%, 0.75/100,000), Polycystic disease (11.3%, 0.70/100,000), reflux nephropathy (9.6%, 0.60/100,000), focal and segmental glomerulosclerosis (8.8%, 055/100,000). Prevalence of ESRF for primary glomerulonephritis was calculated to 20.6% and according to the histological type to 28.3% for idiopathic IgA nephropathy, 34.8% for local and segmental glomerulosclerosis, 40% for idiopathic crescentic glomerulonephritis and only 6.6% for membraneous nephropathy. In the studied area, 58% of patients were treated out of hospital (at home or in self-dialysis units) whose 46% by hemodialysis and 12% by CAPD.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1987

[Ender's so-called alignment nailing in the treatment of trochanteric fractures in the young adult, and under certain circumstances: is it reasonable? Study of a series of 50 cases].

The technique and results of an original method of "alignment Ender's nailing", combining standard Ender's nailing with post-operative traction is described. This method is directed towards young patients in two well-defined situations: the complexity of the trochanteric fracture and the debilitation of the patient. A consecutive series of 50 cases have been analysed. There were no infections and no technical failures. A detailed study of hip and knee function and of the anatomical reconstruction in both antero-posterior and lateral planes with a mean follow-up of 20 months has shown 82.6 per cent of good and very good results.

Adult↗
PubMed1987

[Resection-reconstruction of the femur shaft by a massive allograft fixed by an interlocking nail].

Case report of a central midshaft osteosarcoma of the femur, treated conservatively under Rosen procedure. Bone resection was followed by reconstruction with a deep frozen (-196 degrees) conserved massive homograft, fixed by an interlocked Kuntscher's nail. The purpose of this paper is to expose the advantages of this type of fixation, V.S. conventional nails, or plates. X-Ray showed a bridging bone spindle between host and graft cortical bone, induced by initial stability of the nail, and a rapid fusion after secondary dynamisation of the nail, by removing one screw. We obtained an early functional recovery and a complete and rapid autonomy necessary to allow social and school reinsertion, whatever should the medium or long term presumed survival be.

Adolescent↗
PubMed1987

Cutaneous microthrombi: a histologic clue to the diagnosis of hypereosinophilic syndrome.

Hypereosinophilic syndrome is a rare systemic disease that frequently has cutaneous lesions. Past reviews of the histopathology of the skin lesions have revealed a nonspecific dermal infiltrate with occasional eosinophils as a constant finding. A case of hypereosinophilic syndrome with cutaneous manifestations, in which the skin biopsy demonstrated multiple cutaneous microthrombi, is reported. The diagnostic and prognostic significance of this finding is discussed.

Diagnosis, Differential↗
PubMed1986

[Epidemiology of calcium calculi in a French region. Initial results after 4 years].

Between July 1, 1980 and August 1984, 222 patients (112 men and 112 women) were referred to the Nephrology out-patient clinic of a hospital serving a population of about 250,000. Urolithiasis was revealed by renal colics in 71% of the cases; 64 patients (29%) had been suffering from one or several attacks of renal colic before the study period. The first clinical symptoms appeared between the ages of 20 and 59 years in over 80% of the cases, with a peak of incidence between 30 and 39 years. Calcium stone lithiasis was as frequent in women as in men; the sex ratio was around 1 whatever the patient's age at the onset of the disease; 65% of patients had hypercalciuria on an unrestricted diet. The annual incidence of urolithiasis (hospital cases) was 15.6 for 100,000 inhabitants, and the theoretical prevalence (distribution of new patients aged about 50) 0.8 for 100 inhabitants. These epidemiological data compared with those in the literature, show a relatively low incidence of urolithiasis, notably among men, in that particular region of France.

Adolescent↗
PubMed1986

Increase in blood plasma levels of boron and strontium in hemodialyzed patients.

Boron and strontium concentrations in blood plasma of controls and hemodialyzed patients from two Centers were determined by inductively coupled plasma emission spectrometry. Boron concentrations in blood plasma were respectively, in controls 2.6 +/- 0.9 mumol/l and in hemodialyzed patients 16.1 +/- 5.6 mumol/l before the dialysis session and 9.5 +/- 3.2 mumol/l at the end. The decrease in blood plasma during the dialysis was concomitant with an increase in the dialysis fluid (1.2 +/- 0.7 mumol/l at the beginning and 4.6 +/- 1.8 mumol/l at the end). Strontium concentrations in blood plasma were respectively, in controls 0.22 +/- 0.06 mumol/l and in hemodialyzed patients 0.62 +/- 0.24 mumol/l before the dialysis session and 0.64 +/- 0.14 mumol/l at the end. The mean concentration of strontium in the dialysis fluid was the same before (0.49 +/- 0.11 mumol/l) and after the dialysis session (0.49 +/- 0.10 mumol/l), but a transfer between plasma and dialysis fluid was shown by individual changes. Some considerations about these results are put forward but their possible clinical consequences are not yet known.

Adult↗
PubMed1986

[For a better use of the venous system].

Iatrogenic lesions of the venous system may jeopardize not only the patient's comfort, but also future possibilities of treatment. The fact that the medical staff has little knowledge of the equipment and drugs used for intravenous therapy has been demonstrated by a recent survey. As a result of this survey, several measures aimed at preventing iatrogenic venous lesions are described.

Disinfectants↗
PubMed1986

Blood plasma fluoride in haemodialysed patients.

Blood plasma fluoride was determined in 15 chronic haemodialysed patients (60.2 +/- 7.2 yr old) before and after a 4-h dialysis using dialysates with very low fluoride level, and in two control groups, the first of 20 healthy younger subjects (45.9 +/- 3.4 yr old), the second of 8 healthy older subjects (69.1 +/- 6.8 y old). Before haemodialysis the fluoride concentration (1.31 +/- 0.31 mumol/l; 24.8 +/- 5.9 micrograms/l), was higher than in both control groups (0.35 +/- 0.16 mumol/l; 6.6 +/- 3.1 micrograms/l and 0.44 +/- 0.16 mumol/l 8.4 +/- 3.0 micrograms/l, respectively). During dialysis, the mean fluoride concentration fell to 0.94 +/- 0.26 mumol/l, remaining however, significantly higher than in control subjects. The use of fluoride-free dialysates seems to partially compensate the effect of renal impairment since plasma fluoride is only moderately increased in these patients.

Adult↗
PubMed1986

Remission of idiopathic nephrotic syndrome after treatment with cyclosporin A.

Nephrotic syndrome in minimal change lipoid nephrosis and focal segmental glomerulosclerosis may be due to alteration of glomerular anionic sites by a lymphokine. Six adults with nephrotic syndrome who were resistant to treatment with corticosteroids and immunosuppressants were treated with cyclosporin A. In three patients with minimal change lipoid nephrosis who had been nephrotic for 3.5 to 23 years proteinuria resolved within 12 to 42 days. Subsequently, these patients became dependent on cyclosporin A. In three patients with focal segmental glomerulosclerosis who had been nephrotic for four to six years mean (SD) 24 hour urinary protein decreased from 14.7 (8.4) g to 3.6 (0.6) g within 20 to 25 days, serum albumin concentration rose, and oedema subsided. One patient died of myocardial infarction when still in partial remission after 11 weeks' treatment. Two patients remained proteinuric despite continuing treatment with cyclosporin A, but control of sodium balance was easy and serum albumin concentrations remained higher than without cyclosporin A. In all patients renal function improved during treatment. These preliminary results show that cyclosporin A may be effective in the treatment of patients with nephrotic syndrome that resists every other form of treatment and especially in the treatment of those with minimal change lipoid nephrosis. The results are in keeping with a T lymphocyte mediated mechanism of minimal change lipoid nephrosis and focal segmental glomerulosclerosis, but they also suggest that minimal change lipoid nephrosis and focal segmental glomerulosclerosis are separate entities.

Adult↗