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Biomedical subjects

H Salem

Publications and source records attributed to H Salem.

At least 37 records · Page 2Linked to original sources
PubMed1986

Pharmacokinetics of oral contraceptive steroids in Egyptian women: studies with Ovral, Nordette and Norminest.

Plasma concentration profiles and pharmacokinetic parameters have been obtained following single dose administration of three commonly used oral contraceptive steroid preparations, Ovral, Nordette and Norminest to Egyptian women. The constituents of the preparations are as follows: Ovral (50 micrograms ethinyloestradiol, EE2 and 500 micrograms levonorgestrel, LNG); Nordette (30 micrograms EE2 and 150 micrograms LNG); and Norminest (35 micrograms EE2 and 500 micrograms norethisterone, NOR). Peak plasma concentrations of EE2 ranged between 116-160 pg ml-1 for Ovral, 55-78 pg ml-1 for Norminest and 30-70 pg ml-1 for Nordette. There was no significant difference in half-life (t1/2), oral clearance (CL) or apparent volume of distribution (Vd). The relative values of the area under the plasma concentration-time curve (AUC) reflected well the different amounts of oestrogen in each preparation. There was no significant difference in t1/2, CL or Vd for LNG in the 2 preparations containing this progestogen. The mean AUC following Nordette (150 micrograms LNG) was 40% of that following Ovral (500 micrograms LNG; p less than 0.001). Comparing pharmacokinetic parameters for the same dose of LNG (Ovral) and NOR (Norminest) showed the AUC to be decreased and CL and Vd increased in the latter group. The study indicates that the kinetic profile of the OCS in healthy Egyptian women are similar to other ethnic populations.

Adult↗
PubMed1984

A 13-week vapor inhalation study of n-hexane in rats with emphasis on neurotoxic effects.

Male and female Fischer 344 rats were exposed to 0-, 3000-, 6500-, or 10,000-ppm n-hexane vapors 6 hr per day, 5 days per week, for 13 weeks. The 13-week exposures had no adverse effect on the growth of female rats. However, the mean body weight gain of male rats in the 10,000-ppm group was significantly lower than for controls at 4 weeks of exposure and thereafter. In addition to the depression of body weight gain, the male exposed to 10,000 ppm had slightly but significantly lower brain weights at necropsy. No adverse testicular effects were noted. Axonopathy was observed in the tibial nerve in four of five male rats from the 10,000-ppm group and one of five male rats in the 6500-ppm group and in the medulla from one male rat in the 10,000-ppm group. These axonal changes were detectable only in teased nerve fiber preparations or in Epon embedded specimens. Histopathologic studies on Formalin fixed tissues did not reveal any lesions that were attributed to n-hexane exposure.

Air↗
PubMed1983

A comparison of automated data collection and manual data collection for toxicology studies.

Automated data collection was compared with manual data collection in terms of accuracy and man-hours devoted to data manipulation and checking. The comparison was based on experience with an automated data collection system (DOLPHIN)TM1 developed at Toxigenics for use in conducting toxicological studies. It was found that on-line data collection increases the quality of the data gathered because: 1) it facilitates scientific observation by displaying historical data and statistics on changes since the last observation period; 2) it virtually eliminates errors due to oversight and transcription; 3) it allows more careful monitoring of the course of the study by providing immediate access to interim summary statistics; 4) it provides complete documentation of all changes made to the data after initial collection. In addition, automated data collection enables more rapid completion of the final report of results because: 1) fewer departmental transfers are required; 2) auditing by Quality Assurance (Q.A.) personnel is facilitated.

Data Collection↗
PubMed1983

[Effect of autonomic drugs on Na K adenosine triphosphatase activity in the heart and skeletal muscles].

It has been found that ATP-ase activity increases considerably in the heart after intravenous administration of adrenaline, noradrenaline, phenylephrine (50 micrograms/kg), phentolamine, atropine, and also after vagotomy and adrenaline given after vagotomy. In the skeletal muscle ATP-ase activity increases considerably after noradrenaline, isoprenaline, phenylephrine (50 micrograms/kg), adrenaline given after phentolanine and Ach given after denervation of the muscle. A decrease in the activity of the enzyme in the heart was found after propranolol hexamethonium and Ach given after vagotomy, whereas in the skeletal muscle after Ach, hexamethonium and after muscle denervation. No changes or weak actions in the skeleton muscle are evoked by phenylephrine (10 micrograms/kg), propranolol, atropine, tubokurarine as well as adrenaline given after muscle denervation. In the heart, however, isoprenaline, Ach, adrenaline after propranolol, Ach after atropine and Ach after hexamethonium. A very low involvement of the enzyme studied in utilization of ATP reserves in the heart and skeletal muscle was found. However, of significant importance in this process may be the reactions catalized by extramembrane ATP-ases. The autonomic nervous system effects ATP-ase activity, and stimulation of beta-adrenergic receptor causes an increase in the enzyme activity in both muscles, whereas stimulation of the muskarine receptor decreases the enzyme activity in the heart. Moreover, it was found that stimulation of N2 receptor of the motor plate results in increased ATP-ase activity in the skeletal muscle. The present studies have not brought enough evidence accounting for participation of alpha-adrenergic receptor in regulation of the enzyme studied.

Adrenergic beta-Agonists↗
PubMed1980

Beta-thromboglobulin and platelet aggregates in glomerulonephritis.

Circulating platelet aggregate ratios (CPAR) and plasma beta-thromboglobulin (B-TG) concentrations were determined in 53 patients with chronic progressive glomerulonephritis [mesangiocapillary glomerulonephritis (15) and focal and segmental hyalinosis and sclerosis (38)] and compared with those from both normal subjects and patients with no evidence of renal disease. The mean B-TG concentration was higher in patient controls [32.6 +/- 6.2 ng/ml (SEM)] than in normal subjects [19.0 +/- 2.0 ng/ml (SEM)] but this did not reach significance (P < 0.10 > 0.05). Nephritic patients had markedly elevated levels [49.8 +/- 4.0 ng/ml (SEM)], but B-TG was significantly correlated with renal impairment. Elevated B-TG levels in patients with nephritis may thus reflect renal impairment or ill-health. The mean CPAR of the nephritic patients [0.75 +/- 0.02 (SEM)] was lower than that of both normal [0.86 +/- 0.03 (SEM), P < 0.001] and patient controls [0.87 +/- 0.02 (SEM), P < 0.001]. CPAR was not correlated with renal function or platelet concentration. Low CPAR in nephritic subjects provides further evidence for in-vivo activation of platelets in patients with glomerulonephritis.

Adult↗
PubMed1979

Evaluation of the toxicologic and teratogenic potentials of sodium fluorescein in the rat.

Sodium fluorescein (10%) when injected intravenously (5 ml/kg) in pregnant albino rats crossed the placental barrier and appeared to be distributed throughout the fetus within 15 min. It was detectable in the fetus up to 4 h after injection but not beyond 24 h. A single intravenous administration of sodium fluorescein did not produce embryotoxic or teratogenic effects. Oral LD50 studies using sodium phenobarbital on rats which received sodium fluorescein during their fetal development showed no apparent effects of sodium fluorescein on their drug detoxification systems.

Abnormalities, Drug-Induced↗
PubMed1978

Comparative analgetic testing of various compounds in mice using writhing techniques.

Anti-writhing assays to detect analgesia or specific activity against selected agonists were performed on albino mice. Acetylcholine Cl, bradykinin triacetate, phenylquinone, and serotonin creatinine sulfate were used as agonists. 10 compounds, including 5 standard analgetics, were tested against each agonist. Attempts to study histamine phosphate as an agonist were not successful. Results of these investigations showed satisfactory analgetic acitivity for codeine phosphate and acteyl salicylic acid (ASA) in all assays. weaker analgetics displayed varying degrees of activity depending on the agonist tested. Acute oral toxicities were determined for the 10 test compounds and the analgetic ED50 vs the LD50 of each compound was compared. The data confirmed the nonspecificity for writhing assays as well as a variability in activity of the test compounds against the various agonist.

Acetylcholine↗
PubMed1977

Antiinflammatory activity: evaluation of a new screening procedure.

Acetaminophen, ascorbic acid, aspirin, dexamethasone, indomethacin, and phenylbutazone were tested to evaluate a new antiinflammatory screen. The basic methodology of Rassaert (1) was employed with slight modifications. The technique employs a 50-mm length of cotton twine instead of a cotton pellet. The data confirm the ability of this technique to rapidly screen activity of a variety of chemicals having antiinflammatory activity. It appears that statistically significant reductions in granuloma weight range between 10% and 50%, depending on the test compound and dose employed. This technique demonstrates activity for compounds such as aspirin and acetaminophen only at extremely high doses. However, more potent agents are detectable at more reasonable dose levels. Ascorbic acid, which has been shown to have activity in other models, was inactive in this assay. Dexamethasone was the most active agent, followed by indomethacin and phenylbutazone. Duplicate assays of selected agents showed a satisfactory degree of reproducibility.

Animals↗
PubMed1976

Therapeutic efficacy of a new anhydrous theophylline dosage form.

A clinical study was performed on 41 asthmatic patients. After complete physical and spirometric examinations, they received capsules containing 200 mg anhydrous theophylline per capsule t.i.d. for three weeks. All other antiasthmatic medications were omitted during this study. The results showed that these capsules (Elixophyllin Capsules) produced statistically significant improvement in wheezing, dyspnea, global clinical assessment, vital capacity, and forced expiratory volume at 1 second. Side effects, which were generally mild and transient, were those usually reported for theophylline and were observed in 11 of the 41 patients. One patient dropped out of the study because of extreme nausea. It was concluded that theophylline as a single entity can provide significant improvement in asthmatic patients at a total daily dose of 600 mg.

Adolescent↗
PubMed1975

Conjunctival temperature: a measure of ocular decongestant and anti-inflammatory activity.

A new experimental method is presented that permits objective evaluation of ocular decongestant and anti-inflammatory activity following systemic or local administration of drugs to the rabbit eye inflamed with mustard oil. The inflammation produced by mustard oil is characterized by conjunctival hyperemia and chemosis and is measured by the conjunctival sac temperature. Although a 2% suspension of acetylsalicylic acid (0.1 ml) applied topically to the eye did not markedly reduce conjunctival temperature compared to the control eye, oral administration of 300 mg/kg showed a significant reduction throughout the duration of the experiment. In addition to the anti-inflammatory agent, acetylsalicylic acid, the antihistaminic, antazoline phosphate 0.5% and a vasoconstrictor or decongestant, naphazoline hydrochloride 0.05% were applied individually and in combination (Vasocon-A) locally in the conjunctival sac. Both antazoline phosphate and naphazoline hydrochloride reduced congestion and conjunctival sac temperature while the combination reflected the action of the individual ingredients. The palliative effect of antazoline phosphate indicates that this drug administered topically readily antagonizes histamine in the inflamed eye. There was no corneal anesthesia after instillation of Vasocon-A into the rabbit eye. Antazoline hydrochloride administered in up to 8 times the concentration in Vasocon-A did not induce corneal anesthesia which could be readily obtained with tetracaine hydrochloride.

Administration, Oral↗