Aberrant DNA methylation of tumor suppressor genes has been reported in all major types of leukemia with potential involvement in the inactivation of regulatory cell cycle and apoptosis genes. However, most of the previous reports did not show the extent of concurrent methylation of multiple genes in the four leukemia types. Here, we analyzed six key genes (p14, p15, p16, p53, DAPK and TMS1) for DNA methylation using methylation specific PCR to analyze peripheral blood of 78 leukemia patients (24 CML, 25 CLL, 12 AML, and 17 ALL) and 24 healthy volunteers. In CML, methylation was detected for p15 (11%), p16 (9%), p53 (23%) and DAPK (23%), in CLL, p14 (25%), p15 (19%), p16 (12%), p53 (17%) and DAPK (36%), in AML, p14 (8%), p15 (45%), p53 (9%) and DAPK (17%) and in ALL, p15 (14%), p16 (8%), and p53 (8%). This study highlighted an essential role of DAPK methylation in chronic leukemia in contrast to p15 methylation in the acute cases, whereas TMS1 hypermethylation was absent in all cases. Furthermore, hypermethylation of multiple genes per patient was observed, with obvious selectiveness in the 9p21 chromosomal region genes (p14, p15 and p16). Interestingly, methylation of p15 increased the risk of methylation in p53, and vice versa, by five folds (p=0.03) indicating possible synergistic epigenetic disruption of different phases of the cell cycle or between the cell cycle and apoptosis. The investigation of multiple relationships between methylated genes might shed light on tumor specific inactivation of the cell cycle and apoptotic pathways.

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Venous Thrombo-Embolism (VTE) is a serious complication in hospitalized patients but can be preventable. This prospective study addresses risk factors assessment and the use of heparin in this population. About 2,496 non pediatric patients were admitted to Jordan University Hospital between June 12, 2007 and July 19, 2007. A random sample of 624 patients consisting of every fourth admission was chosen. The stratification of risk factors was assessed using Caprini model and the ACCP score. The mean age of the patients (229 males and 395 females) was 45.34 +/- 18.3 years. More than 80% of the admitted patients were considered at high risk for VTE but heparin was used in only 26% of the patients. The majority of our patients constitute a high-risk population. Implementation of strategies including educational sessions and risk stratification guidelines can reduce the incidence, morbidity, and mortality of VTE especially in developing countries.

We examined platelet aggregation in platelet-rich plasma (PRP) and in whole blood in nine patients with Thrombasthenia Glanzmann (TG). In PRP, aggregation was measured by monitoring the changes in light absorbance that occurred in response to adenosine 5-diphosphate (ADP), collagen and ristocetin. To measure platelet aggregation in whole blood, we used multiple electrode Impedance aggregometry using the same aggregating agents. In PRP, the patient's platelets showed defective aggregation in response to ADP, collagen, epinephrine and partially to ristocetin in all patients. In whole blood, platelet aggregation in response to the same aggregating agents showed similar response and appeared to be very similar to that which occurred in PRP. Whole blood impedance aggregometry seems to give similar results to PRP light transmission aggregometry in patients with TG. Multiple electrode aggregometry (MEA) is faster and more convenient to use in these patients.

Haemophilia A (HA) is an X-linked recessive bleeding disorder caused by mutations in the factor VIII gene (F8), which encodes factor VIII (FVIII) protein, a plasma glycoprotein, that plays an important role in the blood coagulation cascade. In the present study, our aim was to identify F8 gene mutations in HA patients from Jordan. One hundred and seventy-five HA patients from 42 unrelated families were included in this study. Among these patients, 117 (67%) had severe HA, 13 (7%) had moderate HA and 45 (26%) had mild HA. Severe patients were first tested for intron-22 inversion using long range polymerase chain reaction (PCR), then negative patients were tested for intron-1 inversion using PCR. Sequencing for the entire F8 gene was performed for all severe HA patients who were found negative for intron-22 and -1 inversions and it was also performed for moderate and mild HA patients. HA causative mutations were identified in all patients. Intron-22 and -1 inversions were detected in 52% and 2% of families respectively. Beside these two mutations, 19 different mutations were identified, which include 15 missense and four frameshift mutations. Five novel mutations were identified including one frameshift and four missense mutations. No large deletions or nonsense mutations were detected in patients who participated in this study. Only 17 patients with severe HA were found positive for FVIII inhibitors. The data presented will play an important role for genetic counselling and health care of HA patients in Jordan.