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S A Samaan

Publications and source records attributed to S A Samaan.

13 recordsLinked to original sources
PubMed1995

Estrogen and cardiovascular function after menopause.

Nonrandomized trials of postmenopausal estrogen replacement have shown a benefit in the prevention of coronary artery disease. Less clear are the specific mechanisms by which this occurs. Estrogen has beneficial effects on the lipid profile, with significant elevations in high density lipoprotein cholesterol and reductions in low density lipoprotein cholesterol reported. Also, antioxidant properties have been ascribed to estrogen. In addition, estrogen has been shown to prevent paradoxic vasoconstriction in atherosclerotic coronary arteries after acetylcholine and may have calcium channel-blocking and alpha2-inhibiting properties. Other proposed mechanisms of cardiovascular protection include reductions in serum fibrinogen and increases in prostacyclin biosynthesis. There is some evidence that cardiovascular biomechanics may be mildly depressed after menopause and that estrogen may normalize these changes by increasing ventricular contractility and, possibly, relaxation. Far less is known about the cardiovascular effects of progesterone, but overall it does not appear that the less androgenic progestins substantially modify the effects of estrogen. Because more women > 50 years old die of cardiovascular disease than any other cause, further clinical investigations of the risks and benefits of estrogen replacement and combined estrogen and progesterone therapy are clearly needed.

Blood Coagulation Factors↗
PubMed1995

Myocardial atrophy in acquired immunodeficiency syndrome--associated wasting.

This study evaluated the effects of acquired immunodeficiency syndrome wasting syndrome (AWS) on the heart in a population free of overt opportunistic infection or clinical evidence of cardiac disease. Data from 53 patients with AWS and 16 healthy age-matched controls were studied. By echocardiography, a significant reduction in left ventricular mass was found in patients with AWS that remained significantly reduced when corrected for body surface area. Mean ejection fraction was within the normal range in patients with AWS but was significantly less than in controls. End-systolic volume index was slightly elevated in patients with AWS. Although no difference in end-systolic wall stress was seen, the end-systolic wall stress-shortening relation differed significantly. These findings are consistent with myocardial atrophy and subtle left ventricular dysfunction in patients with AWS.

Acquired Immunodeficiency Syndrome↗
PubMed1977

Cutaneous leishmaniasis in the Libyan Arab Republic: preliminary ecological findings.

Preliminary results show cutaneous leishmaniasis in Libya to be, sometimes at least, a rural zoonotic infection. The parasites are transmitted, probably by Phlebotomus papatasi, between the rodents Psammomys obesus and Meriones libycus. The banks and 'islands' in the main channel of seasonal wadis provide the right combination of vegetation and permanence for the maintenance of an intense focus.

Animals↗
PubMed1967

Severity of clinical manifestations of bilharziasis and egg output among children aged 4-5 years in the Egypt-49 project area.

This paper describes a simple schedule which can be used to provide a numerical measure of the severity of infection with S. haematobium, S. mansoni or both, and compares the results obtained by use of this schedule and by use of egg counts. A check list gives a number of clinical signs and symptoms, some of which may be graded according to severity. A "severity factor" is assigned to each sign and symptom, such that the maximum possible score obtainable by summing the individual severity factors is 100. The disease is classified, on the basis of the total score, as asymptomatic, mild, moderate, severe or very severe. This method of grading has been tested on a group of 239 Egyptian children aged 4-5 years for whom egg counts were already available. The results are not conclusive, owing to the relatively small size of the sample studied, but they would seem to indicate that the method of clinical grading used will have to undergo considerable modification before it is suitable for practical use.

Child, Preschool↗
PubMed1966

The epidemiology of Schistosoma haematobium and S. mansoni infections in the Egypt-49 project area. 2. Prevalence of bilharziasis in relation to personal attributes and habits.

The over-all uncorrected prevalence rates of bilharziasis determined in this survey were-Control Division, 59.5%; Rural and Reclamation Divisions, 35.9%; Urban Division, 21.0%. There are significant differences in rates of infection between sections within a division, between adjacent villages and even between different parts of one village. Prevalence increases rapidly with age up to about the age of 14 years, declines somewhat up to the age of 40 years and then remains fairly constant at a rate of about 30%; the age-group 0-8 years should provide the most sensitive group for the assessment of control measures. S. mansoni infection is acquired more slowly than S. haematobium infection during childhood and is more persistent among adults.Except for the youngest age-group, bilharziasis rates are higher in males than in females, but more detailed analysis shows that this is true only for farmers and farm labourers and for those who swim. In respect of occupational categories, farmers and farm labourers, with prevalence rates of 50.6% and 41.6%, respectivelx, bear the brunt of the infection, since they constitute 48% of the population, although fishermen (60.4%) and boatmen (52.0%) have higher infection rates.Differences in bilharziasis rates can also be related to differences in religion, educational attainment and domestic habits (swimming, washing clothes, utensils and cattle) according to the opportunity provided for contact with polluted water. Swimming, because of the thorough exposure to possible schistosome infection that it provides, is one of the most important activities involved in the transmission of bilharziasis.

Adolescent↗
PubMed1966

The epidemiology of Schistosoma haematobium and S. mansoni infections in the Egypt-49 project area. 3. Prevalence of bilharziasis in relation to certain environmental factors.

The influence of the size and location of communities in relation to the different types of watercourse, the availability of a protected water supply, types of housing and the presence of other sanitary facilities on the prevalence of bilharziasis in the Egypt-49 project area has been studied. There is no direct relationship between the size of village and the prevalence of bilharziasis. Main drains and distributaries are potent sources of infection and, in terms of the total population exposed, distributaries play the most significant role in the transmission of infection. Of the other factors, the availability of a protected water supply seems to have the greatest effect on the prevalence. Although the presence of a latrine in the dwelling does not of itself influence the extent of schistosome infection, which is caught from polluted water, the installation of latrines assists in the cultivation of healthy habits, thereby lessening the prevalence not only of bilharziasis but also of certain other infections.

Adolescent↗
PubMed1966

The effect of area-wide snail control on the endemicity of bilharziasis in Egypt.

Molluscicides applied to two areas near Alexandria had a significant effect in reducing both incidence and prevalence of Schistosoma haematobium and S. mansoni infections. No decrease in either measure of endemicity was found in an adjacent untreated area. Bayluscide and sodium pentachlorophenate were equally effective in interrupting the transmission of S. haematobium, but Bayluscide was more effective against S. mansoni, probably because of the difficulty of applying sodium pentachlorophenate to drains, which are the primary habitats for the intermediate hosts of S. mansoni. The authors believe that the present experiment provides strong evidence of the interruption of transmission of bilharziasis in the Nile Valley or Delta.

Child↗
PubMed1966

Assessment of severity of disease caused by Schistosoma haematobium and S. mansoni in the Egypt-49 project area.

The impact of bilharziasis on a community has been evaluated in terms of the stages and grades of severity of the disease; egg counts in faeces and urine were correlated with the clinical severity. At the time this study was carried out, the over-all prevalence of S. haematobium infection was 37.6%, that of S. mansoni infection 29.8% and that of mixed infections 17.1%.Of 579 people examined, 292 (58.2%) were excreting schistosome eggs. All except one person were classified as Stage III-asymptomatic, 122 (41.8% of those infected); mild, 74 (25.3%); moderate, 89 (30.5%); severe, 6 (2.1%). The remaining person was classified as Stage IV (moderate). Mixed infections produced a higher proportion of symptomatic cases (74.8%) than either infection alone (58.2%), and S. haematobium (57.1%) a higher proportion than S. mansoni (37.8%). The percentage of symptomatic cases was highest in those aged 10-14 years, who also had the highest prevalence of infection.On average, the egg output per infection was in the range 32-63 eggs for S. haematobium infections and 4-7 for S. mansoni in unit measure of urine and faeces, respectively. For S. haematobium infections, alone and in mixed infections, mean egg output increased with the severity of clinical symptoms. For S. mansoni infections, no such relation was established.It is concluded that the criteria of severity should be made more objective and that more satisfactory methods of determining egg counts should be adopted in an attempt to obtain more direct evidence of the validity of regarding egg count as a measure of worm load.

Adolescent↗