Experimental study on cryopreservation of platelets / 中国实验血液学杂志

The study was purposed to develop a novel cryopreserved agent (CPA) for platelets, to investigate the morphology of cryopreserved platelets in different CPA and the CD62P expression on membrane of platelets after stimulating by thrombin, as well as to compare the effect of adding UDP-Gal on preserved efficiency of preservation solutions. A novel cryopreserved agent consisting of 2% DMSO, thrombosol and UDP-Gal was developed on basis of using higher concentration of DMSO. The morphology of chilled platelets was observed by transmission electron microscope and compared with fresh platelets. The expression of CD62P on the membrane of platelets was detected at 0, l, 3 months. The results indicated that the significant effect of cryopreservation on morphology of platelets was found according to percentages of round, dendritic and irregular shapes of cryopreserved platelets. The protective effects of 2% DMSO + thrombosol and 2% DMSO + thrombosol + UDP-Gal were better than that of 5% DMSO. Compared with fresh platelets, the expression of CD62P on platelet membrane decreased obviously after cryopreservation, but not observed difference at preservation for 1 month and 3 months, as well as among 3 kinds of different CPA. It is concluded that the protective effects of 2% DMSO + thrombosol and 2% DMSO + thrombosol + UDP-Gal on morphology of platelets are similar, but better than that 5% DMSO. The reaction of cryopreserved platelets to thrombin decreases, while the significant difference is not found among these 3 kinds of CPA. The addition of UDP-Gal to cryopreserved agents not show the protective effect on platelets.

Cold storage of rabbit platelet suspension by adding uridine diphosphate galactose / 中国实验血液学杂志

This study was aimed to investigate the method to cold-store platelets with uridine diphosphate galactose (UDP-Gal). Rabbit heart blood was prepared for concentrated platelet suspension to which UDP-Gal was added, and then stored for ten days in 4 degrees C refrigerator. Thereafter, platelet count, mean platelet volume (MPV), platelet distributing width (PDW), platelet aggregation function, platelet activity to urge coagulation including PF3aT and APCT and apoptosis were determined. Meanwhile, survival time in vivo was tested after cold-stored rabbit platelets labeled with Cr51 were transfused into rabbits. The results showed that there was not significant difference for Plt count, MPV, PDW, PF3aT and APCT between UDP-Gal cold-stored platelet group and fresh platelet group (P > 0.05). On the contrary, platelet count decreased significantly, MPV, PDW jumped and PF3aT and APCT went down in cold control group as compared with fresh platelet group (P < 0.01). Apoptosis increased in UDP-Gal cold-stored platelet group as compared with fresh platelet group (P < 0.05), but was significantly lower than that in cold control group (P < 0.01). Although PagT (inducing reagent: C-PG) decreased, it could still be above 50% of fresh platelet. Survival time in rabbit in vivo was close between UDP-Gal cold-stored platelet group and fresh platelet group (P < 0.05). Survival rate in seventy-two hours after transfusion in the fresh platelet group, UDP-Gal cold-stored platelet group and cold control group was 57.5% +/- 7.2%, 50.3% +/- 6.3% and 0.1% +/- 0.5% respectively. It is concluded that the UDP-Gal can well protect cold-stored rabbit platelets and prolong the survival time of cold-stored platelets in vivo.

Evaluation of the effects of glycosylation on in vivo survival of cold-storage human platelets by using rabbit model / 中国实验血液学杂志

To study the effects of glycosylation on survival of cold-storage human platelets by using rabbit model. (51)Cr-labeling platelets were used to detect the platelet storage survival. The human platelets (2.0 x 10(12)/L) treated with 5 g/L uridine diphosphate galactose (UDP-Gal) were stored in 4 degrees C refrigeratory up to 10 days. The survival of human platelets in rabbits whose reticuloendothelial system was inhibited by the administration of ethyl palmitate was monitored in blood drawn at various times after the platelet transfusion. The results showed that the survival rate of platelets was significantly increased in cold-storage human platelets by UDP-Gal treatment. The survival rates of platelets at 2 hours after transfusion into rabbits in groups of fresh platelets group, UDP-Gal + cold platelets group and cold platelets group were (68.9 +/- 8.5)%, (65.4 +/- 8.0)% and (5.0 +/- 2.6)%, respectively. Compared with cold platelets group, significant differences were seen among all groups (P < 0.01). UDP-Gal + cold platelets group had no significant differences compared with fresh platelets group (P > 0.05). It is concluded that UDG-Gal can provide the protective effect on cold-storage human platelets and prolong the survival time of refrigerated human platelets in rabbit model.

Galactosemia Detected by Neonatal Screening Test

PURPOSE: The genetic disturbance of galactosemia is expressed as a cellular deficiency of either galactose-1-phosphate uridyltransferase(GALT) or galactokinase(GALK) or UDP galactose 4-epimerase(GALE). To find-out the pattern of galactosemia in Korea, we retrospectively analyzed cases of galactosemia detected by neonatal screening program. METHODS: We analyzed medical records of patients who visited Soonchunhyang University Hospital at age of 1 month after showing abnormalities in neonatal screening of galactosemia. For accurate diagnosis, galactose was measured by enzyme immunoassay(EIA) and fluorophotometer, also galactose-1-phosphate by fluorophotometer. Enzyme activities of GALK, GALT and GALE in RBC and galactose-1-phosphate were measured by radioisotope assay(RIA). Beutler test were done. Patients went on a lactose-free diet and follow-up tests for galactose, galactose-1-phosphate level and enzyme activity were performed. RESULTS: 10 patients(male : 6, female : 4) were diagnosed as galactosemia. Two patients had GALK deficiency and two had GALT deficiency. Six were GALE deficient showing the largest number. In two patients with GALK deficiency, GALT and GALE activities were normal but GALK activities showed respectively reduced activity. For GALT deficiency, two patients had low GALT activity in RBC and showed genotype of Duarte 2/G(galactosemia) in DNA analysis. In one patient, GALT activity was normal. Three patients seemed to be heterozygote state of GALE deficiency according to GALE activity levels. Four patients showed GALK hyperactivity. CONCLUSION: GALE deficiency provided the highest number. After lactose-free diet, galactose and galactose-1-phosphate were normaly maintained. Neonatal screening on galactosemia is essential for preventing life-threatening symptoms and an accurate diagnosis is needed for finding out the type of galactosemia which is important for prognosis.

Galactosemia: a treatable metabolic disorder

Case Reports: A term male baby was delivered normally in hospital with Apgar score 10/10 at 5 minutes, weighting 3200 grams and no congenital anomaly was apparent. Baby was sent home same day. He was brought on 5th day with complaint of jaundice. Total Serum bilirubin was 21.0-mg% with predominant indirect hyperbilirubinemia. No evidence of ABO, Rh incompatibility, glucose-6-phosphate dehydrogenase[G6PD] deficiency or any other cause of jaundice detected at this stage. He was admitted in hospital and phototherapy was started. Baby remained active, aferbile, feeding well during hospital stay. Serum bilirubin dropped to 13.0-mg% on 10th day and was discharged in satisfactory condition. But he was readmitted after one day with complaint of poor feeding, drowsiness, hypothermia and lethargy. With clinical impression of neonatal sepsis, injection ceftriaxone and amikacin were started empirically. Mild jaundice was still present. Investigations revealed hemoglobin [Hb] 13.0 gm%, total leukocyte count[TLC] 2800/mm3, platelets 40,000/mm3, blood glucose 60mg% and serum bilirubin 8.0mg%. Condition of baby improved after 24 hours. He became active and started taking feeds. Blood culture revealed growth of E. coli, sensitive to above antibiotics. Antibiotics were continued for 12 days and baby was discharged. On follow up after 10 days at 01-month of age, baby was quite pale looking, deeply jaundiced and not gaining weight. He weighed only 3.3 kg at 35 days of age. Investigations revealed Hb: 8.0 gm%, serum bilirubin 18.0 mg%, Alanine transferase[ALT] 190iu/l, Alkaline phosphatase 1056 u/l with predominant indirect hyperbilirubinemia. Urine examination revealed no abnormality. Ultrasonography[USG] of abdomen revealed mild hepatomegaly with diffuse increased echogenecity. New clinical finding was bilateral lenticular haze [oil droplet type], confirmed by ophthalmologist. Urine for reducing substances was repeated which was strongly positive with Benedict's solution but negative with glucostix. Keeping in mind the possibility of glactosemia, breast-feeding was stopped and replaced with Soy based milk. Red cell concentrate was also transfused and further investigations were done to rule out other causes of persistent indirect hyperbilirubinemia. On induction of lactose free milk, jaundice remarkably regressed in about one week time. Lenticular opacities almost completely disappeared and LFTS became normal in about one month time. Baby is on regular follow up. He is now one year old weighing 9.5 kg and achieving developmental milestones normal for age