Red cell and platelet‐derived microparticles are increased in G6PD‐deficient subjects

In response to oxidative stress and during apoptosis, cells often shed microparticles (MPs), submicron elements carrying phosphatidylserine and protein antigens. Glucose‐6‐phosphate dehydrogenase (G6PD)‐deficient cells are extremely sensitive to oxidative damage that may lead to the formation of MPs. To determine whether G6PD deficiency alters membrane phospholipid asymmetry and increases MPs production, we determined the concentrations and cellular origins of MPs in G6PD‐deficient individuals using flow cytometry. G6PD‐deficient individuals showed an increase in circulating MPs concentrations as compared with G6PD‐normal individuals [1051/μL (865–2532/μL) vs. 258/μL (235–575/μL), P < 0.01]. MPs concentrations were significantly increased with the severity of G6PD deficiency. Median MPs concentrations from individuals with severe G6PD deficiency, and individuals with moderate G6PD deficiency were 2567/μL (1216–2532/μL) and 984/μL (685–2107/μL), respectively (P < 0.01). Importantly, G6PD enzymatic activity was significantly correlated with MPs concentrations with r² = 0.731. MPs found in G6PD deficiency individuals were largely derived from red blood cells (RBCs) (45%) and platelets (30%). Additionally, Atomic Force Microscopy was used to study the morphology and measures the diameter of MPs found in G6PD‐deficient individuals. The mean (SD) width and height of RMPs were 0. 41 (0.18) and 2.04 (0.14) μm, respectively. Together, these results indicate that MP concentration is significantly correlated with G6PD enzymatic activity and is increased in G6PD‐deficient as compared with G6PD‐normal individuals. Our data also provide an evidence for an alteration in cell membrane associated with a decreased in G6PD activity. However, the significance of MPs in G6PD deficiency needs further clarification.     

Dietary intakes and antioxidant status in mind-body exercising pre- and postmenopausal women

Objective

The decline in antioxidant defenses due to both estrogen loss and frequent adoption of poor dietary choices exposes postmenopausal women to cardiovascular diseases. Adequate nutrition and physical exercise are two factors of health promotion. This study investigated whether regular practice of mind-body exercise (yoga and/or tai chi) alters dietary intake and antioxidant status and balances the menopause related increases in lipid peroxidation and cardiovascular risk.

Design

Cross-sectional study. Setting: The study was conducted in an urban community in Bangkok (Thailand) between May and August 2007.

Participants

Premenopausal (Pre M; 39±8 yrs; n=56) and postmenopausal (Post M; 54±5 yrs; n=39) women who had been practicing yoga (Y) and/or tai chi (TC) more than 3 hours/week for a year, or who had no regular physical activity practice (sedentary, S).

Measurements

All participants completed food frequency questionnaires and 4-day food and activity records. Blood was collected on day 5. Factorial ANOVA tests were performed according to menopause status, exercise, and hormone replacement therapy (HRT) groups.

Results

Post M had higher (p = 0.01) dietary fiber intake compared with Pre M. Yoga practitioners had lower BMI (p = 0.004) and lower fat intake (p = 0.02) compared with their S and TC counterparts. Plasma total antioxidant status was significantly and independently lower and higher in Y and Post M groups, respectively. However, no difference was shown after adjusting for BMI. Regardless of menopause status and HRT, the activity of erythrocyte glutathione peroxidase an aerobic training responsive enzyme was higher (p < 0.001 ) in TC practitioners compared with other groups. No effects were shown on erythrocyte superoxide dismutase activity, plasma lipid peroxidation (TEARS) or total homocysteine concentrations.

Conclusion

Yoga and tai chi exercises can be used as components of a strategy to promote healthy lifestyles (balanced diet and moderate intensity exercise) in vulnerable populations, such as menopausal women, in order to prevent aging induced oxidative stress diseases.     

Effects of donor age,donor sex,blood-component processing,and storage on cell-derived microparticle concentrations in routine blood-component preparation

Background

A number of factors cause increases in the number of cell-derived microparticles (MPs) in blood components. However, the overall effects of these factors on the concentration of MPs during routine blood-component preparation have not fully been elucidated.

Flow rate calibration to determine cell-derived microparticles and homogeneity of blood components

Background

Cell-derived microparticles (MPs) are currently of great interest to screening transfusion donors and blood components. However, the current approach to counting MPs is not affordable for routine laboratory use due to its high cost.

Preliminary study of the effect of vitamin E supplementation on the antioxidant status of hemoglobin-E carriers

The antioxidant status of hemoglobin-E carriers was studied pre- and post-treatment with vitamin E for 3 months. Fourteen hemoglobin-E carriers (age = 21.36 +/- 1.08 years, BMI = 18.32 +/- 1.22 kg/m2) were treated with vitamin E 200 I.U. daily for 3 months. Fasting blood samples were collected and analyzed for erythrocyte superoxide dismutase activity, total antioxidant activity, hemoglobin concentration, hematocrit, MCV, Heinz body formation and osmotic fragility test. The blood parameters before and after vitamin E treatment were compared. The results showed that superoxide dismutase activity in the erythrocytes was significantly decreased, while total antioxidant activity in plasma, and the osmotic fragility of the erythrocytes, was significantly increased after vitamin E supplementation. However, hematocrit, MCV, and Heinz body formation did not change significantly. This demonstrated that vitamin E 200 IU could be used as a lipophilic antioxidant in red blood cells and could help increase the level of antioxidant in hemoglobin-E carriers.     

Antioxidant in plasma of hemoglobin-E trait

A study of antioxidant levels among Thai subjects with a hemoglobin E trait was undertaken. The objective of this study was to determine whether the antioxidant level would be disturbed in the HbE condition. All 185 volunteer subjects, 171 normal healthy subjects and 14 HbE carriers were recruited. For each case, an antioxidant determination was performed using the Trolox equivalent antioxidant capacity (TEAC) method. According to this study, the average antioxidant level in the healthy group was 3.439 +/- 0.220 mM Trolox equivalent, and in HbE trait group was 3.276 +/- 0.209 mM Trolox equivalent. There was a significant decrease of the antioxidant level in the HbE trait group (p = 0.008).     

Detection of Cryptococcus neoformans in bird excreta

We evaluated 14 samples of bird excreta from pigeons, parrots, open billed storks and crows obtained from thirteen places in Bangkok and nearby areas between April and July 2004. These bird excreta were examined for Cryptococcus neoformans by direct plating method to inspect their ability to grow at 37 degrees C. Capsule production was examined by Indian ink preparation. They were also tested for urease and phenoloxidase enzymes. Cryptococcus neoformans var neoformans was recovered from pigeon excreta in 9.09%. This implies those having impaired immunity may get this fungus from the environment.     

The effect of green pit viper (Trimeresurus albolabris) venom on platelet morphology by electron microscopy

The incidence of venomous snake bites increases every year in Thailand, especially due to green pit viper. After the bite, there is bleeding due to thrombin-like property of the venom. The mean platelet volume has been reported to be decreased in those who have been bitten by this snake. In this study we investigate the effect of green pit viper venom (Trimeresurus albolabris) on platelet volume (MPV), number and morphology of platelets in vitro. The test was carried out by washing platelets in phosphate buffer at pH 7.2 to remove fibrinogen, then the washed platelets were mixed with green pit viper venom. Platelet morphology was examined by scanning electron microscope (SEM).The morphology of platelets was smaller than normal which ranges from 1.1- 1.2 microm. Green pit viper venom can directly effect platelet morphology, decreasing platelet volume.