The aqueous extracts of Acacia nilotica and Hibiscus sabdariffa were tested for anti-inflammatory, analgesic and antipyretic activities in animal models. Acacia nilotica extract had an inhibitory effect on carrageenan induced paw edema and yeast-induced pyrexia in rats. It also produced a significant increase in the hot plate reaction time in mice. Hibiscus sabdariffa extract had no effect on paw edema but had an inhibitory effect on yeast induced pyrexia and a significant effect on the hot plate reaction time. Among the phytoconstituents found in both plants, flavanoids, polysaccharides and organic acids may be mainly responsible for their pharmacological activities.

The potential toxicity of Acacia nilotica was investigated in rats maintained on 2% and 8% acacia diet for 2 and 4 weeks. A significant reduction in body weight in all acacia-fed groups and a significant decrease in the levels of hemoglobin, serum total protein and total cholesterol in animals fed 8% acacia diet for up to 4 weeks were observed. These effects were, however, reversed one week after treatment termination. No significant changes in serum parameters of hepatic and renal functions, fasting glucose and triglycerides were observed. Further, no deaths among treated animals and no significant histopathological changes in liver sections were noted. It is concluded that A. nilotica, at 2% and 8% levels, has a low toxicity potential.

Plasma zinc and copper concentrations were determined by atomic absorption spectroscopy in 57 patients with sickle cell anemia and in 45 control subjects from the Eastern Province of Saudi Arabia. Plasma zinc and copper levels in patients were found to be close to those of the control subjects. Similarly, there was a difference neither in urinary zinc level nor in the ratio Cu:Zn in patients and control subjects. This is in contrast to the situation which exists in North American Black subjects with sickle cell anemia, who are known to have zinc deficiency as well as a further decrease in zinc level during sickle cell crises. The near-normaLlevels of zinc and copper found in Saudi sickle cell patients therefore exclude zinc deficiency and confirm that this population exhibits a milder form of sickle cell anemia.

Glycosylated hemoglobin was determined by the thiobarbituric acid method in sickle cell anemia patients from the Eastern Province of Saudi Arabia. The level of glycosylated hemoglobin in a Saudi SS sample (4.36%, SD 0.83) is 90% of that of the sample of normals (4.85%, SD 0.51). This is in contrast with the reported value of glycosylated hemoglobin in an American Black SS sample (3.9%, SD 0.6), which is only 60% of that of the sample of normals (6.6%, SD 0.7). The fetal hemoglobin level in Saudi sickle cell patients was 12.03% (SD 4.84), which is significantly different from that of Americans of African origin at p = 0.001. There was no significant correlation (r = 0.236) between the percentages of glycosylated Hb and Hb F at the 10% confidence level. The reported positive relationship between the percentages of glycosylated Hb and Hb F in American Blacks seems to be valid in the Saudi population only up to the level of 10–12% of fetal hemoglobin. Above this threshold of Hb F no further alleviating effect is seen. The 2,3-diphosphoglycerate value in Saudi Hb SS adults was 21.7 μmol/g (SD 7.4) and accordingly only twice as high as that of normal individuals. The benign clinical course exhibited by Saudi sickle cell patients is reflected by the survival of the RBC as indexed by its content of glycosylated Hb and 2,3-diphosphoglycerate. Moreover 10–12% of fetal hemoglobin in the RBC seems sufficient to ameliorate the severity of this disease in patients from the Eastern Province of Saudi Arabia.

SUMMARY. Colorimetric determinations of glycosylated haemoglobin by the thiobarbituric acid method were carried out in normal adults (n=142), newly born infants of healthy mothers (n=81), and in a group of patients with diabetes mellitus (n= 124). The glycosylated haemoglobin level in normal adult males was 4·9%, which is close to that reported for other populations. No correlation was found between age and the levels of glycosylated haemoglobin in males over 10 years old. However, the mean value for glycosylated haemoglobin in cord blood was 4·1%, significantly different from that of adults. The range values for glycosylated haemoglobin in diabetic patients was 7-1lJ'Yo. The mean value for glycosylated haemoglobin was 10.9°/." similar to that established in other diabetic populations. Results of colorimetric determinations of glycosylated haemoglobin in the Saudi population compare well with other ethnic groups and, therefore, suggest no ethnic differences in glycosylated haemoglobin levels.