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Biomedical subjects

A Khalil

Publications and source records attributed to A Khalil.

At least 145 records · Page 8Linked to original sources
PubMed1995

[Cyclosporine A decreases coronary blood flow in dogs].

The objective of the present study was to determine the effect of cyclosporine (CSA) on coronary artery reactivity. Six mongrel dogs, weighing 20 to 30 kg were anesthetized with sodium pentobarbital and were artificially ventilated. A median sternotomy was performed to expose the heart. Left anterior and circumflex coronary flows were measured with an electromagnetic flowmeter. Heart rate, mean arterial pressure, coronary sinus pressure and dP/dt were monitored during all experiments. Blood samples were withdrawn from the coronary sinus to measure CSA. Injections of 5 and 10 mg of CSA in the left anterior descending coronary artery were administered to all animals and the measure of the circumflex coronary blood flow was used as control during the experiments. The decrease in left anterior descending coronary artery blood flow averaged 24 +/- 9% (p = 0.002) and 18 +/- 11% (p = 0.009), and the increase in coronary vascular resistance averaged 31 +/- 12% (p = 0.005) and 16 +/- 24% (p = 0.1) after 5 and 10 mg of CSA, respectively. There were no significant changes in circumflex coronary artery blood flow and in dP/dt during the experiments. Cyclosporine blood levels averaged 453 +/- 226 nmol/l and 1087 +/- 199 nmol/l after injections of 5 and 10 mg of CSA, respectively. In conclusion, this study suggests that CSA can cause acute vasoconstriction of the arterial coronary vasculature.

Animals↗
PubMed1995

[Posterior mediastinal mass].

Bronchogenic cyst of esophagus wall with intracystic haemorrhage in a patient with C hepatitis and portal hypertension. CT and MRI study.

Adult↗
PubMed1995

Lipid profile norms in Indian children.

OBJECTIVES: To evaluate the lipid parameters in normal Indian children. DESIGN: Cross-sectional. SETTING: Hospital based. METHODS: 410 children (siblings of hospitalized pediatric cases) between 3-12 years were evaluated for total plasma cholesterol (TC), triglycerides (TG) and high density lipoprotein cholesterol (HDL-C). The low density lipoprotein cholesterol (LDL-C) levels were derived from the above parameters using Fredrickson-Friedwald formula. RESULTS: No significant difference was found between the sexes in any of the lipid parameters studied. The mean values were: TC-134.5 mg/ dl, TG-91.1 mg/dl, HDL-C-34.15 mg/dl and LDL-C-80.1 mg/dl. The suggested cut off limits for these parameters were 190 mg/dl, 150 mg/dl, 20 mg/dl and 130 mg/d respectively. CONCLUSIONS: Lipid profile norms and cut off levels to define abnormalities for Indian children were recommended. The HDL-C levels were lower than western data.

Child↗
PubMed1994

Effects of cold and warm blood cardioplegia assessed by myocardial pH and release of metabolic markers.

The optimal temperature of blood cardioplegia remains controversial. Interstitial myocardial pH was monitored online with a probe that was inserted in the anterior wall of the left ventricle. Venous pH, lactate production, and creatine kinase and troponin T release were measured in coronary sinus blood obtained in 14 dogs after ischemic arrest periods of 5, 10, 20, and 40 minutes with warm (n = 7; mean myocardial temperature, 35 degrees +/- 2 degrees C) and cold (n = 7; mean myocardial temperature, 12 degrees +/- 1 degree C) blood cardioplegic protection. Blood cardioplegic solution was delivered at a rate of 100 mL/min during the 10 minutes between each ischemic arrest. The interstitial myocardial pH decreased significantly (p < 0.05) from 7.1 +/- 0.3 to 6.53 +/- 0.3 after ischemia in animals perfused with warm blood cardioplegia and from 7.04 +/- 0.3 to 6.64 +/- 0.1 in those receiving cold blood cardioplegic protection; however, the difference between the groups was not significant (p > 0.05). Lactate production and creatine kinase and troponin T release increased significantly after ischemia, but there was no difference in the changes between the warm and cold blood cardioplegia groups. In conclusion, ischemia caused significant changes in all variables measured, and these changes were directly proportional to the duration of ischemia. However, there was no significant difference (p > 0.05) in the myocardial metabolic changes between the warm and cold blood cardioplegia groups in terms of the duration of ischemic arrest studied.(ABSTRACT TRUNCATED AT 250 WORDS)

Analysis of Variance↗
PubMed1994

Spontaneous closure of enterovaginal fistula caused by a neglected foreign body.

The problem of a foreign body left in the operative field is rarely discussed in the medical literature despite the multiple complications it might cause. The purpose of this article is to report on a patient who developed an enterovaginal fistula secondary to a pack left in the pelvis to temponade post-hysterectomy bleeding. The fistula closed spontaneously after three months of expectant management. Expectant management of enterovaginal fistulae is feasible. Adequate reporting of the operative procedures performed and the use of tagged sponges is a must.

Adult↗
PubMed1994

[Right hilar mass and pleural effusion].

One case of bronchogenic cyst associated with a pleural effusion is reported. Computed tomography and magnetic resonance imaging (MRI) findings are described.

Bronchogenic Cyst↗
PubMed1994

Incidence of congenital heart disease among hospital live births in India.

Ten thousand nine hundred and sixty four consecutive live births weighing more than 500 g and more than 28 weeks of gestation were subjected to a thorough clinical examination within 24 h of birth. Those suspected of having congenital heart disease (CHD) were followed up every 4-6 weeks for a period of 6 to 18 months (mean 9.75 months). Forty three of 10,964 infants had CHD, i.e., 3.9/1000 live births. Incidence of CHD was higher in pre-terms as compared to full term live births (22.69 vs 2.36/1000 live births). Diagnosis was confirmed by echocardiography including 2D, Doppler and color flow imaging. Twenty eight per cent of the infants with CHD had other associated somatic anomalies, Down's syndrome being the commonest (9.3%). Patent ductus arteriosus (41.9%) and ventricular septal defects (VSD) (34.9%), were the commonest lesions with an incidence of 1.6 and 1.4/1000 live births, respectively. Incidence of PDA was higher probably because of larger number of pre-term deliveries. During follow up of 6-18 months, 34.9% of the infants with CHD died. The diagnosis of CHD was confirmed at autopsy in 20% of the deaths.

Abnormalities, Multiple↗
PubMed1994

Immunological profile in congenital heart disease.

Fifty children with established congenital heart disease (CHD) were surveyed for the immune profile. Ventricular septal defect (VSD) was the commonest lesion (56%) followed by Tetralogy of Fallot (ToF; 16%), atrial septal defect (ASD; 8%), patent ductus arteriosus (PDA; 4%), transposition of great arteries (TGA; 4%), aortic stenosis (AS; 4%), and pulmonic stenosis (PS), tricuspid atresia (TA), single ventricle with pulmonic stenosis (SV with PS) and dextrocardia with ToF (2% each). Immunoglobulins (IgG, IgA and IgM) were estimated. IgG and IgA levels were significantly reduced in all children with congenital heart disease, whereas IgM levels were increased in cyanotic but unaffected in the acyanotic group. Complement C3 and C4 levels were reduced in all, more so in cyanotics. T-helper cells were decreased and T-suppressor cells were increased in all groups with congenital heart disease as compared to controls. B-cell percentage was increased in cyanotics but not affected in the acyanotics.

Antibody Formation↗
PubMed1994

Myocardial distribution of retrograde cardioplegic solution assessed by myocardial thallium 201 uptake.

Perfusion of the right ventricular myocardium with retrograde infusion of cardioplegic solution through the coronary sinus has been reported to be less than optimal. To study left and right ventricular perfusion during retrograde and antegrade coronary sinus cardioplegia, we added 0.5 mCi of thallium 201 to 500 ml of hyperkaliemic crystalloid cardioplegic solution injected retrogradely into the coronary sinus at low perfusion pressure (20 to 40 mm Hg) in 14 dogs and antegradely in the ascending aorta in seven dogs. The cardioplegic solution was cold (4 degrees C) in eight animals perfused retrogradely and warm (21 degrees C) in 13 animals. After aortic crossclamping, the ascending aorta and the left and right ventricles were vented and cardioplegic solution was injected retrogradely into the coronary sinus. Antegrade injections were performed after aortic crossclamping and venting of the left and right ventricles and of the left and right atrium. After cardioplegic arrest, the heart was harvested, fixed, and scanned with a gamma camera. With cold retrograde cardioplegia, 82% +/- 5% of the injected thallium 201 activity was identified in the myocardium--71% +/- 9% for warm retrograde perfusion and 80% +/- 3% for antegrade perfusion (p > 0.05). Focal areas of hypoactivity in the septum and in the right ventricular free wall were present at scintigraphic imaging in all animals receiving retrograde perfusion. In conclusion, most thallium 201 activity of cardioplegic solution injected retrogradely in the coronary sinus was identified in the myocardium, but focal areas of hypoactivity in the septum and in the right ventricular free wall were present, indicating uneven distribution. Temperature of the crystalloid solution had no effect on the myocardial distribution of the thallium 201 radiotracer in the myocardium.

Animals↗
PubMed1993

Importance of platelets in myocardial injury after reperfusion in the presence of residual coronary stenosis in dogs.

Residual coronary stenosis is common after successful thrombolysis for acute infarction. We investigated the role of platelets and the influence of a residual critical stenosis during early reperfusion in survival of reperfused myocardium. The left anterior descending coronary artery was occluded for 90 minutes and reperfused for 6 hours in 5 groups of dogs, 3 with a residual critical stenosis (groups 1 through 3) and 2 without (groups 4 and 5). Thrombocytopenia was produced by an antiserum in groups 2, 3, and 5; group 3 was also made neutropenic by another antiserum. Platelets (groups 1 and 4) and neutrophils (groups 1, 2, 4, and 5) labeled with indium 111 were reinjected at occlusion. Collateral flow was estimated with radioactive microspheres and was statistically similar among groups. Infarct size (percentage of area at risk), revealed by triphenyltetrazolium, was more severe (49.4% +/- 4.0%; p < 0.05) with stenosis (group 1) than without stenosis (group 4: 29.5% +/- 4.6%). Platelet depletion reduced infarct size in group 2 (28.6% +/- 6.3%; p < 0.05 vs group 1) with stenosis, but not in group 5 without stenosis (24.5% +/- 6.2% vs group 4: 29.5% +/- 4.6%). Neutropenia (group 3) did not decrease infarct size in thrombocytopenic dogs. Neutrophil accumulations in reperfused myocardium were similar among groups, but platelets accumulated in greater numbers in reperfused infarcts with stenosis (group 1: 338,581 +/- 52,857/gm; p < 0.05) than without stenosis (group 4: 153,445 +/- 23,949/gm). Therefore a critical stenosis at reperfusion compromises myocardial salvage and increases infarct size by means of a platelet-mediated mechanism.

Animals↗
PubMed1993

[Peroxidation of human high density lipoproteins by oxygen-derived free radicals].

The involvement of low density lipoprotein (LDL) peroxidation in atherogenesis is now admitted. The oxidation of high density lipoproteins (HDL) could contribute to the atherogenic process, by limiting their capacity to accept cholesterol from cell membranes. In this work, we studied the human HDL peroxidation initiated by OH. or OH./O2.- free radicals generated by gamma radiolysis. This method allows a quantitative and selective production of free radicals, and the resulting oxidation is less drastic than the chemical one. HDL oxidation was followed, as a function of the radiation dose, by the disappearance of endogenous vitamin E, the formation of thiobarbituric acid-reactive substances (TBARS) and the fluorescence at 440 nm. Human HDL turned out to be oxidizable by hydroxyl free radicals and oxygen potentiated this effect. The oxidative modification of HDL, leading to a rigidification of the HDL envelop, could contribute to reduce the ability of HDL to stimulate efflux of cholesterol from tissues.

Free Radicals↗
PubMed1993

[Progressive paraparesis, complication of acquired pagetic synostosis of the cervical vertebrae. 2 cases].

Two cases of pagetic cervical intervertebral synostosis with spinal cord compression are reported. Computed tomography and magnetic resonance imaging enabled detailed analysis of pagetic bone structure and relationships between the fused spinal segment and spinal cord. Few similar cases have been reported and most authors have advocated conservative therapy with calcitonin and/or diphosphonates, with surgery only in cases unresponsive to pharmacotherapy.

Aged↗