ASSESSMENT OF PLATELET CONCENTRATE PREPARED FROM FRESH AND OVERNIGHT HELD WHOLE BLOOD

Separation of platelet rich plasma (PRP) within 8 hours after holding whole blood at ambient temperature is the current practice in the preparation of platelet concentrate (PC). However, the ability to hold whole blood for up to 24 hours prior to PC preparation would allow every unit of whole blood to be used regardless of the distance from the collection site to the processing centre. Therefore the aim of this study is to assess and compare the platelet quality and activation of the platelet concentrate prepared from fresh whole blood (within 8 hours from collection) and overnight hold of whole blood at room temperature. In this study, 23 units of PC were prepared freshly from whole blood (i.e., within 8 hours of collection) and another 23 units were prepared after 24 hours of storage at 20–24 ºC. The following parameters of each unit of PC were assessed: pH, total white blood cell (TWBC) count, platelet count, presence of swirling, and platelet activation. When the parameters were compared between groups, no significant difference in platelet activation rate was found on sampling days 1, 3, and 5. pH and TWBC count for both groups were within the quality requirements of the National Blood Centre (> 75% units tested fall within the standard), but not all of the samples complied with the standard requirement for platelet count. All units of PC prepared after 24 hours showed the presence of swirling, whereas one unit of PC in the fresh group did not show swirling activity after 3 days of storage. Delaying whole blood processing for up to 24 hours does not significantly affect certain in vitro quality or activation parameters as compared with freshly prepared PC. Â

Dengue virus type 2 (DENV2)-induced oxidative responses in monocytes from glucose-6-phosphate dehydrogenase (G6PD)-deficient and G6PD normal subjects.

BACKGROUND: Dengue virus is endemic in peninsular Malaysia. The clinical manifestations vary depending on the incubation period of the virus as well as the immunity of the patients. Glucose-6-phosphate dehydrogenase (G6PD) deficiency is prevalent in Malaysia where the incidence is 3.2%. It has been noted that some G6PD-deficient individuals suffer from more severe clinical presentation of dengue infection. In this study, we aim to investigate the oxidative responses of DENV2-infected monocytes from G6PD-deficient individuals. METHODOLOGY: Monocytes from G6PD-deficient individuals were infected with DENV2 and infection rate, levels of oxidative species, nitric oxide (NO), superoxide anions (O2-), and oxidative stress were determined and compared with normal controls. PRINCIPAL FINDINGS: Monocytes from G6PD-deficient individuals exhibited significantly higher infection rates compared to normal controls. In an effort to explain the reason for this enhanced susceptibility, we investigated the production of NO and O2- in the monocytes of individuals with G6PD deficiency compared with normal controls. We found that levels of NO and O2- were significantly lower in the DENV-infected monocytes from G6PD-deficient individuals compared with normal controls. Furthermore, the overall oxidative stress in DENV-infected monocytes from G6PD-deficient individuals was significantly higher when compared to normal controls. Correlation studies between DENV-infected cells and oxidative state of monocytes further confirmed these findings. CONCLUSIONS/SIGNIFICANCE: Altered redox state of DENV-infected monocytes from G6PD-deficient individuals appears to augment viral replication in these cells. DENV-infected G6PD-deficient individuals may contain higher viral titers, which may be significant in enhanced virus transmission. Furthermore, granulocyte dysfunction and higher viral loads in G6PD-deificient individuals may result in severe form of dengue infection

Frequencies of HBV, HCV, HIV, and Syphilis Markers Among Blood Donors: A Hospital-Based Study in Hodeidah, Yemen

Purpose: This study aimed to determine the frequency rates of human immunodeficiency virus (HIV), hepatitis B virus (HBV), hepatitis C virus (HCV), and syphilis among blood donors. Methods: Physically fit persons aged 18 – 48 years who came for blood donation at the blood bank unit of the military hospital in Hodeidah, Yemen (MHH) from November 2008 to October 2010 were screened using standard diagnostic (SD) reagents. Based on the results, donors with clinical anemia and with history of jaundice were excluded. Results: A total of 1,483 male donors (96 % semi-voluntary and 4 % replacement donors) with a mean age of 24.3 years were enrolled in this study. The frequencies of HBV, HCV, HIV and syphilis in the samples were 2.35, 0.79, 0.14, and 0.34 %, respectively. Compared with the first year, the decrease in HBV and HCV positive cases and the increase in HIV and syphilis positive cases in the second year were not statistically significant (p = 0.91, p = 0.74, p = 0.72, and p = 0.92, respectively). Conclusion: While the frequency rate of transfusion-transmitted infections (TTIs) is low, it remains a major problem in blood transfusion. Proper protocol should be applied in selecting and screening donors to safeguard the health of people receiving blood transfusions

Molecular Characterization of α- and β-Thalassaemia among Malay Patients

Both α- and β-thalassaemia syndromes are public health problems in the multi-ethnic population of Malaysia. To molecularly characterise the α- and β-thalassaemia deletions and mutations among Malays from Penang, Gap-PCR and multiplexed amplification refractory mutation systems were used to study 13 α-thalassaemia determinants and 20 β-thalassaemia mutations in 28 and 40 unrelated Malays, respectively. Four α-thalassaemia deletions and mutations were demonstrated. −−SEA deletion and αCSα accounted for more than 70% of the α-thalassaemia alleles. Out of the 20 β-thalassaemia alleles studied, nine different β-thalassaemia mutations were identified of which βE accounted for more than 40%. We concluded that the highest prevalence of (α- and β-thalassaemia alleles in the Malays from Penang are −−SEA deletion and βE mutation, respectively

Oxidative stress accumulation in DENV-infected monocytes from G6PD-deficient and normal controls.

<p>The accumulation of oxidative stress in monocytes of both normal controls and G6PD-deficient donors increased significantly (p<0.001) after DENV2 infection. In a time-dependent manner, monocytes from G6PD-deficient subjects accumulated significantly (p<0.001) higher oxidative stress compared to monocytes from normal controls.</p

Production of superoxide anions (O^2.−) in DENV-infected monocytes from G6PD-deficient, and normal controls.

<p>The production of superoxide anions (O^2.−) in monocytes of both normal controls and G6PD-deficient donors increased significantly (p<0.001) after DENV2 infection. In a time-dependent manner, monocytes from G6PD-deficient subjects produced significantly (p<0.001) lower O^2.− than monocytes from normal controls.</p

G6PD levels in normal controls and G6PD-deficient subjects.

<p>G6PD levels were determined by a commercially available fluorimetric assay. The mean G6PD activity for G6PD-deficient individuals was 0.285±0.26 IU/g Hb, compared to 13.56±2.02 IU/g Hb for age matched normal controls.</p

Production of nitric oxide (NO) in DENV-infected monocytes from G6PD-deficient, and normal controls.

<p>The production of nitric oxide (NO) in monocytes of both normal controls and G6PD-deficient donors increased significantly (<i>p</i><0.001) after DENV2 infection. In a time-dependent manner, monocytes from G6PD-deficient subjects produced significantly (<i>p</i><0.001) lower NO than monocytes from normal controls.</p