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Biomedical subjects

F Hakkou

Publications and source records attributed to F Hakkou.

17 recordsLinked to original sources
PubMed2004

Prevention of diazepam withdrawal syndrome by nifedipine-behavioural and neurochemical studies.

Our studies aimed at investigating whether the dihydropyridine calcium antagonist, nifedipine, could prevent anxiogenic-like consequences of diazepam withdrawal in rats. Animals withdrawn from chronic diazepam (2 mg/kg/day i.p. for 2 weeks) drank significantly less water than did control rats in the unfamiliar arm of a Y maze. This anxiogenic-like effect could be prevented by acute administration of nifedipine (at 10 mg/kg i.p., but not at lower doses), which, on its own, did not change water intake in naive rats. Given chronically in combination with diazepam for the second half of a 2-week treatment with this drug, nifedipine (at the daily dose of 5 mg/kg i.p.) also suppressed the reduction of water intake normally observed on diazepam withdrawal. Biochemical measurements showed that acutely, as well as chronically, administered nifedipine increased 5-HT turnover in the hippocampus of diazepam-treated rats, thereby suggesting that the prevention of diazepam withdrawal-induced anxiogenic behaviour by the calcium antagonist might be underlain by serotoninergic mechanisms.

Animals↗
PubMed2001

Sleep during Ramadan intermittent fasting.

During the month of Ramadan intermittent fasting, Muslims eat exclusively between sunset and sunrise, which may affect nocturnal sleep. The effects of Ramadan on sleep and rectal temperature (Tre) were examined in eight healthy young male subjects who reported at the laboratory on four occasions: (i) baseline 15 days before Ramadan (BL); (ii) on the eleventh day of Ramadan (beginning of Ramadan, BR); (iii) on the twenty-fifth day of Ramadan (end of Ramadan, ER); and (iv) 2 weeks after Ramadan (AR). Although each session was preceded by an adaptation night, data from the first night were discarded. Polysomnography was taken on ambulatory 8-channel Oxford Medilog MR-9000 II recorders. Standard electroencephalogram (EEG), electro-oculogram (EOG) and electromyogram (EMG) recordings were scored visually with the PhiTools ERA. The main finding of the study was that during Ramadan sleep latency is increased and sleep architecture modified. Sleep period time and total sleep time decreased in BR and ER. The proportion of non-rapid eye movement (NREM) sleep increased during Ramadan and its structure changed, with an increase in stage 2 proportion and a decrease in slow wave sleep (SWS) duration. Rapid eye movement (REM) sleep duration and proportion decreased during Ramadan. These changes in sleep parameters were associated with a delay in the occurrence of the acrophase of Tre and an increase in nocturnal Tre during Ramadan. However, the 24-h mean value (mesor) of Tre did not vary. The nocturnal elevation of Tre was related to a 2-3-h delay in the acrophase of the circadian rhythm. The amplitude of the circadian rhythm of Tre was decreased during Ramadan. The effects of Ramadan fasting on nocturnal sleep, with an increase in sleep latency and a decrease in SWS and REM sleep, and changes in Tre, were attributed to the inversion of drinking and meal schedule, rather than to an altered energy intake which was preserved in this study.

Adult↗
PubMed2000

Daytime alertness, mood, psychomotor performances, and oral temperature during Ramadan intermittent fasting.

During the month of Ramadan, Moslems abstain from drinking and eating daily between sunrise and sunset. This change of meals schedule is accompanied with changes in sleep habit, which may affect diurnal alertness. This study examined the effect of Ramadan intermittent fasting on the diurnal alertness and oral temperature in 10 healthy young subjects. The cognitive task battery including movement reaction time (MRT), critical flicker fusion (CFF) and visual analogue scale, was administered at 6 different times of the day: 09.00, 11.00, 13.00, 16.00, 20.00 and 23.00 h on the 6th, 15th, and 28th days of Ramadan. The baseline day was scheduled one week before Ramadan, and the recovery day 18 days after this month. Oral temperature was measured prior to each test session and at 00.00 h. During Ramadan oral temperature decreased at 09.00, 11.00, 13.00, 16.00 and 20.00 h and increased at 23.00 and 00.00 h. Subjective alertness decreased at 09.00 and 16.00 h and increased at 23.00 h. Mood decreased at 16.00 h. MRT was increased at the beginning of Ramadan (R6) and CFF was not changed. These results showed that daytime oral temperature, subjective alertness and mood were decreased during Ramadan intermittent fasting.

Adult↗
PubMed2000

Influence of Ramadan on the pharmacokinetics of a single oral dose of valproic acid administered at two different times.

This study was carried out in healthy volunteers in order to examine the influence of changes in eating and rest/activity rhythms during Ramadan on the pharmacokinetics of valproic acid (VPA; Depakine). A single oral dose of 800 mg was administered to the first group of subjects (n = 7) at 8:00 PM and to the second group (n = 5) at 5:00 AM. Each group was submitted to three treatment phases: the first was carried out 3 weeks prior to Ramadan (PR), the second one at the end of the first week of Ramadan (R1) and the last at the end of the third week of Ramadan (R3). The plasma kinetics of VPA were determined for each treatment schedule throughout the 50 h following drug intake. During Ramadan, a significant decrease was observed in the Cmax (56.22 +/- 5.32 mg/l in PR vs. 48.35 +/- 5.07 mg/l in R3; p < 0.05) and in the AUC(0.50 h) (1429.92 +/- 284.23 in PR vs. 1090.26 +/- 277.73 mg.h/l in R3; p < 0.05) for the 8:00 PM intake. For the 5:00 AM intake, a significant decrease was observed in the t1/2 (12.15 +/- 1.45 h in PR vs. 9.55 +/- 1.97 h in R3; p < 0.05) and AUC(0.50 h) values (1241.29 +/- 239.01 mg.h/l in PR vs. 1019.21 +/- 256.86 mg.h/l in R3; p < 0.05). These parameters showed a significant decrease at the end of the third week of Ramadan (R3), compared to the control period (PR).

Administration, Oral↗
PubMed1998

Potential serotonergic interactions with the anxiolytic-like effects of calcium channel antagonists.

In a series of experiments, we investigated the interaction between the calcium channel antagonist, nifedipine, and the 5-HT1A agonist, ipsapirone. In the first experiment, we demonstrated that nifedipine (20 mg/kg), and to a lesser extent nimodipine (20 mg/kg), exerted an anxiolytic-like effect as did diazepam (5 mg/kg) in an experimental paradigm based on water consumption in a novel environment. In the second experiment, nifedipine (1.25, 2.5, and 5 mg/kg), and in the third experiment, ipsapirone (1.5. 3.0, and 6.0 mg/kg), have been found to exert a dose-dependent effect in the same test. Finally, a small and ineffective dose of ipsapirone (1.5 mg/kg) potentiated the anxiolytic-like effect of various doses of nifedipine. The data obtained are discussed in terms of the potential anxiolytic-like action of calcium channel antagonists and in relation to their electrophysiological effects. Moreover, the interaction between ipsapirone and nifedipine is discussed in terms of the possible involvement of central serotonergic systems in the behavioral effects of the calcium channel antagonists.

Animals↗
PubMed1997

Ramadan diet restrictions modify the circadian time structure in humans. A study on plasma gastrin, insulin, glucose, and calcium and on gastric pH.

The rule of Ramadan (1 month of food and water intakes restricted to night hours) is followed by the majority of the Moslem fraction of the human population, but the possible consequences of this long-lasting modification of food intake schedule on public health have not yet been extensively documented. Therefore, a group of healthy control subjects and a group of healed duodenal ulcer patients were studied before (controls), during (both groups), and after (both groups) the month of Ramadan. The time-restricted food and water intakes were associated with variations of gastric pH, plasma gastrin, insulin, glucose, and calcium documented on a circadian basis. All of the studied biological variables, except insulin, underwent changes in their 24-h mean concentration (e.g. decrease in gastric pH, increase in plasma gastrin), some of which were still present 1 month after the end of Ramadan. The circadian patterns of all the studied variables were altered during the month of Ramadan. Some differences between the group of healthy control subjects and the group of healed duodenal ulcer patients may suggest a greater susceptibility of the latter to the modifications of feeding and sleeping schedule, which could possibly be a risk factor for the disease.

Adult↗
PubMed1997

[Effect of Ramadan fasting on intragastric pH recorded during 24 hours in healthy subjects].

OBJECTIVES: Lifestyle changes during Ramadan as the meals are taken exclusively in the evening, and nightly sleep is often delayed and shortened. The wake/sleep cycle is also modified. The aim of this study was to evaluate the influence of Ramadan on gastric acidity in healthy volunteers. METHODS: Nine healthy volunteers had 24-hour measurement of the gastric pH; 4 periods were compared: one week prior to Ramadan, day 10 and day 24 during Ramadan, and one month after Ramadan. The pH profiles and the [H+] activity (area under the curve) were measured during 24 hours, the night phase (5PM-8AM) and diurnal phase (8AM-5PM). RESULTS: The diurnal variations of the pH profile were more significant; the median pH was 2.3 prior to Ramadan, 1 at day 10 and day 24 and 1.6 one month after Ramadan. The 24-hours [H+] activity increased by 45% at day 10 of Ramadan compared with its level prior to Ramadan. This increase was mostly diurnal (+122%) and also nightly (+25%). The activity [H+] was steady during Ramadan. One month after Ramadan, the 24-hours [H+] activity was 23% higher than the one noted before Ramadan. CONCLUSIONS: This study shows that the conditions of feeding imposed by Ramadan are associated with an increase of the gastric acidity mainly in diurnal phase. These results do not explain the origin of the healthy volunteer digestive symptoms encountered during Ramadan.

Adult↗
PubMed1994

[The observance of Ramadan and its repercussion on gastric secretion].

The influence of the Ramadan on the gastric secretion has been assessed in 13 volunteers. Their basal and pentagastrin-stimulated secretion has been collected before, during and one month after the Ramadan. Gastric activity, pepsin activity, sialic acid bound to glycoprotein, choline and gastrinaemia have been measured. During Ramadan, acid secretion was increased (+ 159%; P = 0.02) and it recovered the pre-Ramadan level, one month later. Pepsin secretion was also increased during the Ramadan (+ 133%; P = 0.05) and it was significantly reduced after Ramadan. The secretion before the Ramadan was related to vagal hypertony, decreased during Ramadan and was substituted by a gastrinic stimulation after the Ramadan. Mucolysis and gastrinaemia were not modified and no duodenogastric reflux was observed during and after the Ramadan. The Ramadan induces an increase of acid and pepsin secretion. This increase was reversed when Ramadan stopped. These gastric secretion modifications are likely involved in the increase of dyspeptic symptoms observed during the Ramadan.

Adult↗
PubMed1991

Behavioral effects of a calcium channel antagonist: nifedipine.

A series of experiments investigated the behavioral effects of a calcium channel antagonist, nifedipine. This antagonist has facilitatory effects on learning and memory as assessed by the active and passive avoidance tests respectively. In the forced swimming test, nifedipine at a dose of 5 mg/kg had an inhibitory effect on immobilization. Finally, nifedipine (2.5 and 5.0 mg/kg) induced an anxiolytic effect in the water consumption test in a novel environment. These findings are discussed with respect to other findings in the same field and to the neurochemical changes known to be induced by calcium channel antagonists.

Animals↗
PubMed1990

A comparative study of cyproheptadine and DL carnitine on psychomotor performance and memory in healthy volunteers.

This study was performed in order to investigate the extent and severity of cyproheptadine effects on psychomotor performance, mood and memory functions and to compare them to the effects of DL carnitine, another appetite stimulant. Twelve healthy volunteers received 2 doses (at 800 am and 1200 am) of 6 mg cyproheptadine, 1600 mg DL carnitine and placebo on separate days at a weekly intervals. The study followed a double-blind, latin-square design. Assessment of dependent variables was performed 1 h after the first and 1 h and 5 h after the second administration of the drug. On each of these occasions, the following measurements were performed: choice reaction time (CRT), critical flicker fusion (CFF), digit symbol substitution test (DSST), short-term memory (paired words association test), long-term memory (picture test) and 100 mm visual analogue scales of subjective ratings (VAS). Cyproheptadine significantly impaired objective measures (CFF) and subjective ratings both at 1 h and 5 h after the second dosage. Compared with cyproheptadine, DL carnitine induced a slight improvement in psychomotor performance as assessed by CRT. None of the drugs had any effect on memory and on appetite at the doses studied. In conclusion, cyproheptadine at usual doses had a sedative effect, the intensity and duration of which implied a certain risk in performing daytime functions eg when driving, or manipulating machines. DL carnitine had no effect on vigilance.

Adult↗
PubMed1984

Psychopharmacological profile of diphenylhydantoin in mice.

The pharmacological profile of diphenylhydantoin has some common features with that of classical antidepressants: it decreases motor activity in mice it shortens the period of immobility of mice in the "behavioral despair" test it antagonizes palpebral ptosis induced by reserpine in mice.

Animals↗
PubMedDate not supplied

Epidemiological study: chronotype and daytime sleepiness before and during Ramadan.

Few epidemiological data have been reported on the relation between Ramadan fasting, life habits (meal frequency, sleep habits) and daytime sleepiness during Ramadan. This paper presents the results of a detailed study of the chronotype and daytime sleepiness before and during Ramadan. It was conducted on a sample of 264 subjects aged between 20 and 30 years. Results have revealed a significant decrease in the meal frequency during Ramadan compared with the control period. Before Ramadan, the majority of subjects woke up between 6 and 7 a.m. and went to sleep between 10 and 11 p.m. however, during Ramadan fasting, they woke up after 8 a.m. and preferred to go to sleep later (after midnight). Chronotype as evaluated by the Horne and Ostberg scale was changed significantly during Ramadan: an increase of the evening type and a decrease in the morning type of subjects was observed. Daytime sleepiness as evaluated by the Epworth Sleepiness Scale was significantly increased.

Adult↗
PubMedDate not supplied

[Drug prescription and utilization in Morocco].

The aim of this study was to assess drug prescription and utilization in Morocco 8 years after the statement of the Action Program for Essential Drugs. To evaluate the role of essential drugs in these prescriptions, a study of about 600 prescriptions and questionnaires sent to a random sample of 111 prescribers and a series of visits with the investigator as a neutral observer was undertaken. The average number of drugs prescribed was 3.27, which reflected the feelings of most of the clinicians, for whom 3 drugs per patient is the required number. The number of drugs prescribed is lower in the public health structure (2.0 +/- 0.14 depending on the type of institution: hospital or primary health care centre). Specialties from the national list of essential drugs accounted for 15.48 per cent of all drugs which is to be compared with 16.2 per cent of the clinicians stating knowledge of the action programme for essential drugs. In public structures, these prescriptions ranged between 29.8 per cent and 82.4 per cent of the essential drugs (WHO general list). The length of the visit ranged between 3.27 +/- 0.96 min and 4.87 +/- 1.04 min according to the health centres and prescriptions included at least one antibiotic in 47.5 per cent of cases (25 per cent to 64 per cent). At least one antibiotic was prescribed in 43.3 per cent of cases in the study of prescriptions and 17.3 per cent of prescriptions included at least one injectable drug. The average cost of one prescription was 146.25 dirhams (ranging between 4 and 1200 dirhams = US $17). According to 68.6 per cent of the prescribers, the patients felt there to be a strong relation between efficacy and cost. Among the prescription motivations, cost ranked above availability of the drug and after efficacy.

Drug Prescriptions↗