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Background: The Levant is a crucial region in understanding human migrations between Africa and Eurasia. Although some mitochondrial DNA (mtDNA) studies have been carried out in this region, they have not included the Jordan area. This paper deals with the mtDNA composition of two Jordan populations., Aim: The main objectives of this article are: first, to report mtDNA sequences of an urban and an isolate sample from Jordan and, second, to compare them with each other and with other nearby populations., Subjects and Methods: The analyses are based on HVSI and HVSII mtDNA sequences and diagnostic RFLPs to unequivocally classify into haplogroups 101 Amman and 44 Dead Sea unrelated individuals from Jordan., Results: Statistical analysis revealed that, whereas the sample from Amman did not significantly differ from their Levantine neighbours, the Dead Sea sample clearly behaved as a genetic outlier in the region. Its outstanding Eurasian haplogroup U3 frequency (39%) and its south-Saharan Africa lineages (19%) are the highest in the Middle East. On the contrary, the lack ((preHV)1) or comparatively low frequency (J and T) of Neolithic lineages is also striking. Although strong drift by geographic isolation could explain the anomalous mtDNA pool of the Dead Sea sample, the fact that its mtDNA lineage composition mirrors, in geographic origin and haplogroup frequencies, its Y-chromosome pool, points to founder effect as the main cause. Ancestral M1 lineages detected in Jordan that have affinities with those recently found in Northwest but not East Africa question the African origin of the M1 haplogroup., Conclusion: Results are in agreement with an old human settlement in the Jordan region. However, in spite of the attested migratory spreads, genetically divergent populations, such as that of the Dead Sea, still exist in the area.

A high-resolution, Y-chromosome analysis using 46 binary markers has been carried out in two Jordan populations, one from the metropolitan area of Amman and the other from the Dead Sea, an area geographically isolated. Comparisons with neighboring populations showed that whereas the sample from Amman did not significantly differ from their Levantine neighbors, the Dead Sea sample clearly behaved as a genetic outlier in the region. Its high R1*-M173 frequency (40%) has until now only been found in northern Cameroonian samples. This contrasts with the comparatively low presence of J representatives (9%), which is the modal clade in Middle Eastern populations, including Amman. The Dead Sea sample also showed a high presence of E3b3a-M34 lineages (31%), which is only comparable to that found in Ethiopians. Although ancient and recent ties with sub-Saharan and eastern Africans cannot be discarded, it seems that isolation, strong drift, and/or founder effects are responsible for the anomalous Y-chromosome pool of this population. These results demonstrate that, at a fine scale, the smooth, continental clines detected for several Y-chromosome markers are often disrupted by genetically divergent populations.

Twenty alleles for the locus human leukocyte antigen (HLA-A) and 46 for the HLA-B locus were detected in Jordanians. This indicates the existence of high polymorphism in this area. The most frequent HLA class I alleles found were A*0201 (0.1344), B*0713 (0.1724), and C*0502 (0.1793). Twenty-six different alleles in the Jordanian population were identified for the DRB1 locus being the DRB1*0704 (0.2552), DRB1*0401 (0.1965), and DRB1*1501 (0.0896) the most frequent. Common DQA1 alleles were DQA1*0201 (0.2690), DQA1*0301 (0.2414), and DQA1*0501 (0.1724). Three-loci haplotype heterogeneity was common: 38 HLA class II haplotypes were identified, of which the most frequently observed was DRB1*0401-DQA1*0301-DQB1*0302 (0.1793). In addition, as expected, 220 different five-loci haplotypes with several unusual allelic combinations were observed, although many of them are pan-European haplotypes. The most frequent five-loci haplotype was the A30-B7-DRB1*03-DQA1*0501-DQB1*0201 (0.0138). It seems that the specific Jordanian haplotypes are the following: the A31-B7-DRB1*04/07-DQA1*0301/0201-DQB1*0302/0202 haplotypes (0.0103) and the A1-B7-DRB1*07-DQA1*0201-DQB1*0202, A2-B7-DRB1*04-DQA1*0301-DQB1*0302, A11-B7-DRB1*07-DQA1*0201-DQB1*0201 haplotypes but at lower frequencies (0.007). A tree analysis of HLA class I and class II alleles were made for several Caucasian populations and individual genetic distances calculated. The haplotype frequencies, genetic distances, and dendrograms do not reveal great differences as compared with those in other Mediterranean countries and Western Europeans populations. Our results suggest that both HLA class I and class II polymorphism (but especially the former) of the Jordanian population demonstrates considerable heterogeneity, which reflects ancient and recent admixture with neighboring populations, and important human migratory trends throughout the history.

The effect of hyperoxia on the level of the antioxidants: glutathione (GSH) in the whole blood and the enzymes, catalase, superoxide dismutase (SOD), glucose-6-phosphate dehydrogenase (G6PD) and 6-phosphogluconate dehydrogenase (6-PGD), was studied in the erythrocytes of male high school students living at Dead Sea level (390 m below Sea level and 794.7 mm Hg), and compared with those of students living at Amman level (766 m above sea level and 697.5 mm Hg). The levels of the antioxidant enzymes were found to be lower at Dead Sea level than in Amman, except for the catalase level, which was similar in both groups. The ratio of GSH/Hb was significantly higher in the blood of students at Dead Sea level than in Amman. The combined activities of the antioxidants protected the RBC's but permitted increased level of GSH/Hb in the blood to protect peripheral cells from damage by oxidants.

Background and Methods: The clinical and biochemical aspects of two cases of PK deficiency associated with chronic hemolytic anemia in two unrelated patients are reported. The residual erythrocyte PK enzymes in both patients were characterized by the recommended methods of the International Committee for Standardization in Hematology (ICSH)., Results and Conclusions: Patient (W.Q.) had 60% residual PK activity and may be considered homozygous on the basis of consanguinity in the family. This patient suffered from moderate hemolytic anemia that improved after splenectomy. The enzymatic properties were: low activity, moderate thermal stability, reduced affinity for phosphoenol-pyruvate (PEP), and normal electrophoretic mobility. Patient (E.O.) had 42% residual PK activity and may be considered compound heterozygous since his parents are not related. He suffered from moderate hemolytic anemia. The enzymatic properties were: low activity, moderate thermal stability, reduced affinity for PEP and minimal retardation in electrophoretic migration. Theses two cases of PK deficiency are the first to be discovered in Jordan and probably the first in any Arab country.

GM1 ganglioside and nerve growth factor both promote the recovery of injured central cholinergic neurons in young animals. Brain cholinergic activity declines with aging and nerve growth factor has been shown to correct cholinergic deficits in senescent animals. We have administered GM1, to young (three months old) or senescent (22-24 months old) rats and evaluated acetylcholine and choline content, choline acetyltransferase and acetylcholinesterase activity as well as choline uptake in striatum, hippocampus and frontal cortex. For some studies, nerve growth factor was administered alone or together with GM1. Our results indicate that cholinergic neurochemical parameters are decreased in some brain areas of senescent animals and that both GM1 and nerve growth factor can enhance their recovery.

The inhibition of acetylcholinesterase (AChE) by caffeine, anabasine, methylpyrrolidine and several derivatives was examined. Most of the compounds had moderate inhibitory activity with I50 values in the range of 87-480 microM. The inhibition of AChE by these compounds has not been previously reported. A structural feature common to these compounds is the N-methyl determinant of the pyrrolidine ring which may be important in binding to the AChE.

Two glucose-6-phosphate dehydrogenase (G6PD) variants were investigated. G6PD Amman-1 was partially purified from the red cells of a patient suffering from recurrent jaundice and spontaneous episodic attacks of severe hemolysis in the absence of oxidant drugs, infection, or fava beans. The enzymatic characteristics of G6PD Amman-1 were markedly reduced activity, fast eletrophoretic mobility, slightly increased km for NADP, normal km for G-6-P, normal heat stability, normal utilization of substrate analogues 2-deoxy G-6-P and deamino-NADP, and a monophasic pH curve with a peak at 8.5 to 9.3. The second variant, G6PD Amman-2, was partially purified from the red cells of a patient suffering from recurrent jaundice with episodic mild hemolysis caused by infection or unknown factors. G6PD Amman-2 characteristics were severely reduced activity, slow electrophoretic mobility, normal km for NADP, decreased km for G-6-P, decreased heat stability, increased utilization of substrate analogues, and a monophasic pH curve with a narrow peak at pH 9.5. The red cell level of reduced glutathione was markedly decreased with twofold increase in the activity of glutathione reductase in the patient with G6PD Amman-2.

A method is presented that determines the degree of attachment of cancer cells to normal cells. This method may be useful in determining the extent to which treatment of normal cells (or of a tumor-bearing host) with a particular chemotherapeutic agent may affect the degree of attachment of cancer cells to the normal cells. The effects of several diacridines upon this process are described. In addition, we have determined the ability of individual diacridines to alter the permeability of P-388 cells; this effect has been related to their antitumor properties. In general, the most effective antitumor diacridines are those that cause minimal disruption of cell permeability. Conversely, diacridines that disrupt cell permeability tend to have poor antitumor properties. It is considered that the toxicity of these compounds may be a necessary consequence of the assays used for testing anticancer agents, and may not necessarily be related to their antitumor activity.

Human and rabbit erythrocyte membranes prepared by hypotonic hemolysis contained 5 to 15% of the phosphofructokinase in the erythrocytes. The membrane-bound phosphofructokinase can be eluted by a saline wash. Human erythrocyte and rabbit muscle phosphofructokinase bind to the saline-washed membranes. This binding is specific for the inner surface of the membrane. The amount of phosphofructokinase bound is dependent on pH; at pH 7, 6 times more enzyme is bound than at pH 7.5. Unlike free phosphofructokinase, the membrane-bound phosphofructokinase is not inhibited by ATP or 2,3-diphosphoglycerate, and its fructose-6-P saturation curve is nonsigmoidal.