Viroje Chongkolwatana

One-year experience of nucleic acid technology testing for human immunodeficiency virus Type 1, hepatitis C virus, and hepatitis B virus in Thai blood donations

BACKGROUND: Blood donations collected at the National Blood Center, the Thai Red Cross Society, Bangkok, in 2007 were tested by nucleic acid amplification technology (NAT) using the Chiron TIGRIS/Procleix Ultrio test and the Roche cobas s 201/cobas TaqScreen multiplex (MPX) test.

Occult hepatitis B virus infection in Thai blood donors

BACKGROUND: An evaluation by the National Blood Center, the Thai Red Cross Society, of two commercial multiplex nucleic acid tests (NATs; the Chiron PROCLEIX ULTRIO test and the Roche Cobas TaqScreen MPX test) for screening Thai blood donors for hepatitis B virus (HBV), hepatitis C virus, and human immunodeficiency virus Type 1 identified 175 HBV NAT–reactive/hepatitis B surface antigen (HBsAg)‐negative donors. The classification of the HBV infection of these donors was confirmed by follow‐up testing.

Differences in levels of platelet-derived microparticles in platelet components prepared using the platelet rich plasma, buffy coat, and apheresis procedures

BACKGROUND There has been an increased interest in platelet-derived microparticles (PMPs) in transfusion medicine. Little is known about PMP status during the preparation of platelet concentrates for transfusion. AIM The aim of this study is to compare the PMP levels in platelet components prepared using the buffy coat (BC), platelet-rich plasma platelet concentrate (PRP-PC), and apheresis (AP) processes. METHODS Platelet components were prepared using the PRP-PC and BC processes. Apheresis platelets were prepared using the Trima Accel and Amicus instruments. The samples were incubated with annexin A5-FITC, CD41-PE, and CD62P-APC. At day 1 after processing, the PMPs and activated platelets were determined using flow cytometry. RESULTS Both the percentage and number of PMPs were higher in platelet components prepared using the Amicus instrument (2.6±1.8, 32802±19036 particles/μL) than in platelet components prepared using the Trima Accel instrument (0.5±0.4, 7568±5298 particles/μL), BC (1.2±0.6, 12,920±6426 particles/μL), and PRP-PC (0.9±0.6, 10731±5514 particles/μL). Both the percentage and number of activated platelets were higher in platelet components prepared using the Amicus instrument (33.2±13.9, 427553±196965 cells/μL) than in platelet components prepared using the Trima Accel instrument (16.2±6.1, 211209±87706 cells/μL), BC (12.9±3.2, 140624±41003 cells/μL), and PRP-PC (21.1±6.3, 265210±86257 cells/μL). CONCLUSIONS The study suggests high variability of PMPs and activated platelets in platelet components prepared using different processes. This result may be important in validating the instruments involved in platelet blood collection and processing.

Genetic characterization and genotyping of hepatitis B virus (HBV) isolates from donors with an occult HBV infection

Screening of Thai blood donors has resulted in the detection of donors with an occult HBV infection (OBI), where HBsAg is undetectable, but hepatitis B virus (HBV) DNA is present in serum in low concentrations. This study was designed to determine whether the occurrence of OBI in donors was linked to the HBV genotype and possibly to mutations in the surface (S) and core (C) gene regions.

Comparison of fibroblast survival in freeze- dried irradiated platelets, fresh concentrated platelets, or foetal bovine serum

Purpose. To compare the survival of human fibroblasts in freeze-dried irradiated platelets, fresh concentrated platelets, or foetal bovine serum. Methods. 3, 10, 30, and 100 μg protein/ml of freeze-dried irradiated platelets or fresh concentrated platelets, or 5%, 15%, and 50% of foetal bovine serum were each added to the culture medium with human fibroblasts. Controls had no growth factors or serum added. The initial number of fibroblasts was 5000 per well plate. After 72 hours of incubation, the number of living fibroblasts was measured using the MTT (dimethylthiazol diphenyl tetrazolium bromide) assay. Inter- and intra-group differences were compared. Results. After 72 hours of incubation, the number of living fibroblasts was highest in wells with foetal bovine serum, followed by fresh concentrated platelets, freeze-dried irradiated platelets, and controls. Inter-group differences between the controls and each of the other groups were significant. Intra-group differences were significant for all subgroups with fresh concentrated platelets (except 30 vs 100 μg) and foetal bovine serum. Conclusion. Freeze-dried irradiated platelets contain enough growth factor activity for fibroblast survival and may be used to promote wound healing.

Normal cognitive functioning in a patient with Hb Bart's hydrops successfully cured by hematopoietic SCT.

Normal cognitive functioning in a patient with Hb Bart’s hydrops successfully cured by hematopoietic SCT

Invalid freeze-dried platelet gel promotes wound healing

Wound healing is the curative process of tissue injury, composed of three phases: the inflammatory phase, proliferative phase, followed by the maturation cum remodeling phase. Various treatment options were previously depicted for wound healing, however a treatment that accelerates these phases would be highly valuable. Platelet aggregation at the bleeding vessels and release of various growth factors are the most promising factors that stimulates the wound healing progress. In the present study, we hypothesized that the freeze-dried platelet which were normally discarded from the blood banks due to invalidity, might be promising to accelerate the phases of wound healing. The invalid freeze-dried platelets were prepared to a gel form called invalid freeze-dried platelet gel (IF-PG), which was tested for its efficacy in a cutaneous punch wound model in rats. Mupirocin antibiotic gel was used as a bio-equivalent formulation. The wound healing phases and changes in the wound sites were determined by assessing the wound sizes, histopathological analysis, immunohistochemical staining. The re-epithelialization at the wound sites at different time intervals till the wound closure was also determined. Our results suggest the beneficial effects of IF-PG; in reducing the wound area and accelerating wound closure in the cutaneous punch wound in rats. Histopathology and immunostaining results support the improvements in the wound when treated with IF-PG, which were similar to that of mupirocin antibiotic gel. Our preliminary findings also warrant the competency of IF-PG in modulating the different phases of wound healing process. In conclusion, IF-PG might be a resourceful alternative for the wound care management, however further studies are required to validate its impact on various growth factors before proceeding to clinical studies.

Roczne doświadczenie w badaniu metodami biologii molekularnej ludzkiego wirusa niedoboru odporności typu 1, wirusa zapalenia wątroby typu C oraz wirusa zapalenia wątroby typu B u krwiodawców w Tajlandii

Background: Glucose-6-phosphate dehydrogenase (G6PD) enzyme deficiency and methemoglobinemia adversely impact on blood transfusion safety by significantly increasing blood storage lesion. Objective: To determine G6PD enzyme deficiency and methemoglobin levels among blood donors in a tertiary hospital-based blood bank in Nigeria. Subjects and Methods: One hundred blood donors who met the criteria for blood donation were prospectively studied. Two milliliters of venous blood was collected from each participant into potassium-ethylenediaminetetraacetic acid specimen containers and analyzed for G6PD status and methemoglobin levels by spectrophotometry, on the same day of sample collection. Results: Among the donors, 43% had normal G6PD activity (9.32 ± 2.26 U/gHb), 44% had partially enzyme deficiency (4.92 ± 1.33 U/gHb), while 13% had total deficiency (0.47 ± 3.49 U/gHb); these were statistically different (P < 0.001). Methemoglobin concentration was elevated in 25% of study participants (3.05 ± 2.30%), while it was normal in 75% (0.99% ± 0.60%); these differences were statistically different (P < 0.001). Conclusion: A significant proportion of our blood donor set has G6PD enzyme deficiency (partial or total) as well as evidence of oxidation of hemoglobin; these findings have adverse implications on transfusion safety.