ABSTRACT
<p><b>OBJECTIVE</b>To investigate the blood test patterns for blood donors after nucleic acid detection in blood center.</p><p><b>METHODS</b>The collected blood samples after voluntary blood donors first were detected by conventional ELISA, then 31981 negative samples were detected via HBV/HCV/HIV combined nucleic acid test of 6 mixed samples(22716 cases) or single samples(9265 cases) by means of Roche cobas s201 instrument. The combined detection method as follows: the blood samples were assayed by conventional nucleic acid test of 6 mixed samples, at same time, 6 mixed samples were treated with polyethylene glycol precipitation method to concentrate the virus, then the nucleic acid test of blood samples was performed; the single detection method as follows: firstly the conventional nucleic acid test of single sample was performed, then the positive reactive samples after re-examination were 6-fold diluted to simulate the nucleic acid test of 6-mixed samples. The positive rate of positive samples detected by combined nucleic acid test, positive samples detected by nucleic acid test of mixed virus concentration and positive samples detected by single nucleic acid test was statistically analyzed. In addition, for HBVpersons the serological test yet should be performed.</p><p><b>RESULTS</b>In 22 716 samples detected by nucleic acid test of 6 mixed samples (MP-6-NAT) , 9 cases were HBV(0.40‰, 9/22716); at same time, the detection of same samples by nucleic acid test of mixed sample virus concentration showed 29 cases of HBV(1.28‰, 29/22716). In 9265 samples detected by single nucleic acid test(ID-NAT) 12 cases showed HBV(1.30‰, 12/9265), meanwhile the detection of these 12 samples with HBVby 6-fold dilution for virus concentration found only 4 samples with HBV. In serological qualified samples, ID-NAT unqualified rate was 1.28‰, which was higher than that of MP-6-NAT(0.4‰) (χ=8.11, P<0.05); but there was no statistical difference between unqualified rate of ID-NAT and MP-6-NAT(1.3‰ vs 1.28‰)(χ=0.00, P>0.05). In 41 samples with HBsAgHBV DNAdetected by ELISA, 36 samples were confirmed to be occult HBV infective(OBI) by HBsAb, HBcAb test of ELISA; out of these 41 samples, 33 samples showed HBcAb(91.66% of OBI), 5 might be HBV "window period" infective, moreover the HCV RNA and HIV RNA positive samples were not found.</p><p><b>CONCLUSION</b>To avoid the missdiagnosis of donors with low level of virus, the nucleic acid test must be carried out after virus concentration of mixed samples when the blood test pattern of donors is nucleic acid test of mixed samples, otherwise the single nucleic acid test must be performed to obtain more high detected rate of virus nucleic acid. The HBcAb serologic test and physical examination of donors before blood donation must be enhanced on basis of serological test of HBsAg; for high risk people, the persuading no blood donation is simplest pattern.</p>
ABSTRACT
This study was purposed to investigate the effects of N-Arachidonoylethanolamine (ANA) on the quality of platelets (Plt) stored in Plt M-sol preservative solution at 22 ± 2°C. Samples taken from collecting apheresis Plt by the Amicus instrument and splited into two equal parts were stored in Plt M-sol preservative solution on a shaker at 22 ± 2°C. Different working concentrations of ANA (from 0.1 to 50 µmol/L) were then added into one part of stored Plt as the experimental group, the other without ANA was used as the control group. The viability of Plts stored at 22 ± 2°C for 7 days was evaluated by MTT colorimetric assay. The most effective concentration of ANA was selected and added to the subsequent experimental group. Plt count (BPC), mean Plt volume (MPV), Plt distribution width (PDW), phosphatidyl serine (PS) and soluble P-selectin were detected on the 1(st), 5(th), 7(th), 9(th) and 11(th) day of storage. The results showed that the most effective working concentration of ANA was 0.5 µmol/L, which showed significant increasing Plt viability (91.23 ± 5.44%) compared to the control group (62.54 ± 4.79%). Thus, ANA concentration at 0.5 µmol/L was choose to perform subsequent experiments. During 11 days of storage, the BPC, MPV and PDW were not changed significantly between the experimental group and control group, although there was decreasing trend in the BPC and increasing trends in MPV and PDW in the two groups. The rate of Plt PS positive was enhanced during the storage period: the rate of PS positive in experimental group increased from 7.69 ± 1.82% to 10.74 ± 1.78% while it in control group increased from 11.21 ± 2.03% to 15.37 ± 1.95%, with significant differences between the two groups (P < 0.05) on the 9(th) and 11(th) day of storage, respectively. Soluble P-selectin contents in experimental group on the 9(th) and 11(th) day of storage were 30.19 ± 2.03 ng/ml and 34.52 ± 2.64 ng/mL, respectively, while those in control group were 39.18 ± 2.66 ng/ml and 43.23 ± 2.58 ng/ml, respectively, with significant differences between the two groups (P < 0.05). It is concluded that the extended storage of Plt in M-sol treated with low concentration ANA can potentially alleviate Plt storage lesions.