Search PubMed⌕ Search

Biomedical subjects

M Saleh

Publications and source records attributed to M Saleh.

At least 127 records · Page 7Linked to original sources
PubMed1989

Acute and chronic effects of a nutmeg extract on the toad heart.

Electrocardiographic and flexible suction electrode techniques were used to investigate the effects of a nutmeg extract on the toad heart. Acute treatment with the extract resulted in a dose-related sinus tachycardia, faster atrioventricular conduction speed and an increased amplitude of ventricular action potential. Chronic treatment resulted in sinus bradycardia and decreased amplitude and increased duration of ventricular action potential.

Action Potentials↗
PubMed1989

Evidence from neuron/lymphoma heterokaryons for a common trans-acting factor suppressing Thy-1 expression.

We have investigated the tissue specificity of a trans-acting regulatory factor observed to suppress Thy-1 expression during normal neuronal differentiation. Heterokaryons were constructed between Thy-1.1+ expressing mouse T cell lymphoma cells and Thy-1.2- mouse sensory neurons and their surface phenotypes determined by immunofluorescence histochemistry 16 h after fusion. Thy-1.1 expression was observed to be specifically suppressed in such heterokaryons whilst the expression of the lymphoma cell surface marker, Ly-1, was not altered. As the nuclei did not fuse in the heterokaryons, it appears that the developmentally regulated diffusible suppressor factor active in sensory neurons is not tissue specific and can down-regulate Thy-1 expression in lymphoma cells. We also report the suppression of the H-2Kk surface antigen in heterokaryons by a similar but independent regulatory mechanism.

Animals↗
PubMed1989

Experimental model of varicocele.

The purpose of this investigation was to create a varicocele model in animals and to study the subsequent alterations in testicular physiology. The study comprised 22 dogs divided into 2 groups: test and control. In the test group (17 dogs), excision of a longitudinal strip of the fasciomuscular tube of the spermatic cord was done on one side only. In the control group (5 dogs), the spermatic cord was exposed without interference with the tube. Testicular temperature was measured, and biopsies from the 2 testicles and semen specimens were examined. Re-examination for variceal changes was performed in 3 dogs at the 4th postoperative week; in 3 dogs at the 6th, and in 16 dogs (11 test and 5 control) at the 8th postoperative week. Sections from spermatic cord and testicle were examined microscopically. Serum levels of testosterone follicle-stimulating hormone, luteinizing hormone and prolactin were assayed preoperatively and at the time of re-examination. Manifest varicocele was detected in 16 of 17 detubated dogs. It was huge in all dogs re-examined after 8 weeks. Semen showed decreased sperm count in all test animals except 1. The animals with induced varicocele had higher testicular temperature than the controls. Microscopically, the detubated spermatic cords have shown variceal changes and the testicle degenerative changes in all the test animals. Similar changes were encountered in the contralateral testicle in the animals re-examined at 8th week. Radioimmunoassay showed a significant decrease of serum testosterone and increase of prolactin postoperatively. Follicle-stimulating hormone and luteinizing hormone showed no significant change from the preoperative level.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1989

A bioequivalence study of two dipyridamole products.

Bioequivalence of Antiplate 75 mg was assessed versus Persantine 75 mg in a two-way crossover study. At the 5% confidence level, no significant difference was found between the area under the plasma concentration-time curves of the two products. The Cmax were comparable for both products. Quality control data including assay, content uniformity, disintegration and dissolution indicated that both products passed the pharmacopoeial requirements, USP XXI and BP 1980, Addendum 1983. It is concluded that Antiplate-75 is bioequivalent to Persantine.

Adult↗
PubMed1988

Thy-1-mediated regulation of a low-threshold transient calcium current in cultured sensory neurons.

The physiological effect of ligand binding to the Thy-1 molecule expressed on the neuronal cell surface was examined. Sensory neurons obtained from dorsal root ganglia of 2-day-old CBA/CAH mice (Thy-1.2) were cultured in vitro for 8 days, and then patch-clamp recordings were obtained of calcium currents. It was found that binding of an anti-Thy-1.2 monoclonal antibody to neurons expressing the Thy-1.2 moiety increased the amplitude of a low-threshold transient calcium current. Monoclonal antibodies directed against the Thy-1.1 molecule or a neuronal surface ganglioside (A2B5) had no effect on this calcium current in Thy-1.2-bearing cells, nor did they interfere with subsequent activation by the anti-Thy-1.2 monoclonal antibody. These results demonstrate that ligand binding to the Thy-1 molecule transduces a physiological signal in sensory neurons by increasing a voltage-activated calcium current.

Animals↗
PubMed1988

Effect of commercial immunoglobulin G preparation on human monocyte Fc-receptor dependent binding of antibody coated platelets.

This study examined the in vitro effect of a commercial immunoglobulin preparation on human monocytes and the Fc-receptor dependent binding of antibody coated platelets. Monocytes were exposed to Sandoglobulin in vitro and subsequently examined for membrane surface bound IgG. Dramatic increments of surface IgG were found which were maximal with 18 h exposure and somewhat higher at 4 degrees C than 37 degrees C. Ultracentrifugations of Sandoglobulin immediately prior to monocyte exposure reduced the monocyte membrane IgG by 75%. The 18 h exposure at 37 degrees C produced dramatic impairment of monocyte Fc-receptor binding of IgG coated platelets (P less than 0.001) while exposure for 18 h at 4 degrees C produced a modest impairment of Fc-receptor function. These studies indicate that Sandoglobulin contains IgG aggregates which are able to firmly bind to the monocyte surface in a time and temperature dependent fashion. The dramatic impairment of Fc-receptor function at 37 degrees C and not at 4 degrees C suggests that Fc-receptor modulation, as well as competitive inhibition/steric hindrance, contribute to impairment of monocyte Fc-receptor function.

Antigen-Antibody Reactions↗
PubMed1986

Effects of an extract of khat (Catha edulis) on the toad heart.

The effects of acute and chronic administration of an extract of Catha edulis on the heart of the toad were investigated. ECG and ventricular action potential were recorded simultaneously from the surface of the heart of spinal pithed toads before and after administration of different doses of khat extract. Acute treatment resulted in a dose-dependent chronotropic effect and an increase in the amplitude of ventricular action potential. Chronic treatment on the other hand resulted in a negative chronotropic effect and a reduction in the amplitude of ventricular action potential. The observed responses are explained on the basis of the catecholamine releasing effect of components of khat extract.

Action Potentials↗
PubMed1986

Phase I clinical trial of CO17-1A monoclonal antibody.

Twenty patients with metastatic gastrointestinal cancer received one or more weekly infusions of 400 mg CO17-1A monoclonal antibody. The most common side effect was mild gastrointestinal symptoms in 9/20 patients. Two of five patients receiving three weekly infusions had reversible anaphylactic reactions at the time of their third infusion. The pharmacokinetics of the antibody were similar at the first, second or third infusion. Human antibody to 17-1A occurred in 17/20 patients with 11/20 having antibody detectable by 8 days following initial infusion. Thus, one or two infusions (weekly) of large doses of 17-1A were well tolerated but allergic responses limit ability to administer therapy by 15 days post-initial infusion.

Animals↗
PubMed1985

In defence of gait analysis. Observation and measurement in gait assessment.

The gait pattern of five amputees was recorded by visual observation and also by a quantitative measurement system. The results were compared with the gait pattern predicted from biomechanical analysis. Visual observation was found to be an unreliable clinical skill. The observers recorded only 22.2% of the predicted gait deviations and were unable to comment on 15.6% of all the required observations. The gait parameters which were difficult to assess visually, namely step length and step time, are considered by most workers to be of particular value as diagnostic clinical indicators in gait assessment. The measurement system used was accurate in recording gait deviations and picked up 3.4 times as many deviations as visual observation. This report demonstrates the inadequacy of visual observation as a diagnostic method and emphasises the need for measurements.

Amputees↗
PubMed1984

[Thoracic internal bleeding following subclavian puncture in a child].

We report the case of a four year old female patient who underwent an unsuccessful puncture of the subclavian vein in another department with an adult subclavian catheter. Unilateral haematothorax with massive bleeding from the right Art. thoracica interna occurred as a sequel of this attempt and was successfully treated in our department.

Blood Pressure↗
PubMed1982

Glutathione reductase from human erythrocytes. The sequences of the NADPH domain and of the interface domain.

1. Sequence analysis of the NADPH domain (residues 158--293) and of the interface domain (365--478) was based on 12 CNBr fragments, which were isolated using ion-exchange chromatography and paper methods. Fragments with more than 15 residues were digested further with trypsin and chymotrypsin. The isolated peptides were sequenced by automated solid-phase Edman degradation. All sequenced peptides were ordered and overlapped by computerized comparisons with a complete sequence guessed from the electron density map of the protein. In the case of short CNBr fragments, this alignment was confirmed by the sequence analysis of protein fragments resulting from incomplete CNBr cleavage. 2. In the NADPH domain, residue 197, which is involved in an induced-fit mechanism, was identified as a tyrosine. The structure of the NADPH domain is probably homologous with the NAD domain of lipoamide dehydrogenase and with the FAD domain of several proteins, but not with NADPH domains of known chain-fold in other proteins. 3. The paper completes the sequence analysis of glutathione reductase so that the enzyme is now known in atomic detail. The numbering scheme of the chemically determined sequence will be used henceforth in crystallographic studies also. As inferred from the sequence data each of the two identical chains contains 478 amino acid residues, the composition being Cys10, Asp21, Asn17, Thr31, Ser31, Glu29, Gln11, Pro24, Gly43, Ala42, Val44, Met15, Ile29, Leu34, Tyr13, Phe14, Lys34, His16. Arg17, and Trp3. From these data an Mr of 2 x 51 600 was calculated for the FAD-free apoenzyme and an Mr of 2 x 42 400 for the holoenzyme.

Amino Acid Sequence↗
PubMed1981

The use of acebutolol with hydrochlorothiazide in hypertension.

The antihypertensive effect of acebutolol 400 mg and hydrochlorothiazide 25 mg in combination have been assessed in 22 patients with mild, moderate and severe hypertension. In the supine position, blood pressure went down from an average of 190/116 mm Hg to 147/91 mm Hg after treatment, while in the standing position, blood pressure went down from an average of 188/117 mm Hg to 143/94 mm Hg. Age, sex and duration of hypertension have no significant influence upon the antihypertensive effect of this combination. Good results were obtained in 68% of the patients, fair results in 23% and poor results in another 9%. Compared with the use of acebutolol alone, its combination with hydrochlorothiazide showed better results. In mild hypertension good results increased from 75% after acebutolol only to 100% after this combination. In moderate hypertension the percentage of good results increases from 47% to 60% and in severe hypertension good results increased from 50% to 67%. Increase of decrease in heart rate had no relation to the antihypertensive effect of this combination.

Acebutolol↗