Cross-reactive antibodies against monkeypox virus exist in the population immunized with vaccinia Tian Tan strain in China.

Monkeypox virus (MPXV) belongs to the Orthopoxvirus genus. The worldwide outbreak of MPXV in 2022 has caused widespread concerns. Cross-reactive antibodies induced by vaccinia-inoculation can provide protection against reinfection by MPXV. The vaccinia Tian Tan (VTT) strain, which was widely inoculated in the Chinese population before the 1980s, has genomic differences from other vaccinia strains, although they all belong to the orthopoxviruses family. The current seroprevalence of VTT-vaccinated populations remains unclear more than four decades after the termination of vaccination campaigns in China. Our results showed that cross-reactive IgG antibodies against MPXV were present in 31.8% (75/236) of vaccinees four decades after VTT-vaccination, suggesting that vaccination with VTT may provide long-term protection against MPXV infection in some individuals.

Prediction of Red Blood Cell Demand for Pediatric Patients Using a Time-Series Model: A Single-Center Study in China.

Background: Red blood cells (RBCs) are an essential factor to consider for modern medicine, but planning the future collection of RBCs and supply efforts for coping with fluctuating demands is still a major challenge. Objectives: This study aimed to explore the feasibility of the time-series model in predicting the clinical demand of RBCs for pediatric patients each month. Methods: Our study collected clinical RBC transfusion data from years 2014 to 2019 in the National Center for Children's Health (Beijing) in China, with the goal of constructing a time-series, autoregressive integrated moving average (ARIMA) model by fitting the monthly usage of RBCs from 2014 to 2018. Furthermore, the optimal model was used to forecast the monthly usage of RBCs in 2019, and we subsequently compared the data with actual values to verify the validity of the model. Results: The seasonal multiplicative model SARIMA (0, 1, 1) (1, 1, 0)12 (normalized BIC = 8.740, R 2 = 0.730) was the best prediction model and could better fit and predict the monthly usage of RBCs for pediatric patients in this medical center in 2019. The model residual sequence was white noise (Ljung-Box Q(18) = 15.127, P > 0.05), and its autocorrelation function (ACF) and partial autocorrelation function (PACF) coefficients also fell within the 95% confidence intervals (CIs). The parameter test results were statistically significant (P < 0.05). 91.67% of the actual values were within the 95% CIs of the forecasted values of the model, and the average relative error of the forecasted and actual values was 6.44%, within 10%. Conclusions: The SARIMA model can simulate the changing trend in monthly usage of RBCs of pediatric patients in a time-series aspect, which represents a short-term prediction model with high accuracy. The continuously revised SARIMA model may better serve the clinical environments and aid with planning for RBC demand. A clinical study including more data on blood use should be conducted in the future to confirm these results.

Single-Nucleotide Polymorphism LncRNA AC008392.1/rs7248320 in CARD8 is Associated with Kawasaki Disease Susceptibility in the Han Chinese Population.

BACKGROUND: Kawasaki disease (KD) is a multisystem vasculitis in infants and young children and involved in the NOD-like receptor family, pyrin domain-containing 3 (NLRP3) inflammasome activation. Genetic factors may increase the risk of KD. To assess the association between rs7248320 in long noncoding RNA (lncRNA) AC008392.1 located in the upstream region of CARD8 and the risk of KD, a case-control study was conducted in the Han Chinese population. METHODS: This study genotyped the polymorphism rs7248320 in the lncRNA AC008392.1 gene using the TaqMan real-time polymerase chain reaction assay. The genetic contribution of rs7248320 was evaluated using odds ratios (ORs) and 95% confidence intervals (CIs) using unconditional logistic regression analysis. The association between rs7248320 and KD susceptibility was analyzed by performing a hospital-based case-control study including 559 KD patients and 1055 non-KD controls. RESULTS: In this study, a significant relationship between rs7248320 and KD risk was observed in the genotype/allele frequency distribution. The rs7248320 polymorphism was associated with a significantly decreased risk of KD after adjustment for age and sex (AG vs AA: adjusted OR = 0.80, 95% CI: 0.64-0.99, P = 0.0421; GG vs AA: adjusted OR = 0.71, 95% CI: 0.51-1.00, P = 0.0492; AG/GG vs AA: adjusted OR = 0.78, 95% CI: 0.63-0.96, P = 0.0186). Moreover, the rs7248320 G allele also exhibited a decreased risk for KD (adjusted OR = 0.83, 95% CI: 0.72-0.97, P = 0.0193) compared with the A allele. In the stratification analysis, compared to the rs7248320 AA genotype, AG/GG genotypes were more protective for males (OR = 0.71, 95% CI: 0.55-0.93, P = 0.0122). CONCLUSION: This study suggests for the first time that the lncRNA AC008392.1 rs7248320 polymorphism may be involved in KD susceptibility in the Han Chinese population.

Corrigendum: The Immune System in Transfusion-Related Acute Lung Injury Prevention and Therapy: Update and Perspective.

[This corrects the article DOI: 10.3389/fmolb.2021.639976.].

Transfusion Reactions in Pediatric Patients: An Analysis of 5 Years of Hemovigilance Data From a National Center for Children's Health in China.

Objective: This study aimed to describe transfusion reactions of pediatric patients from a National Center for Children's Health in China and to examine reaction incidents, reaction types by blood transfusion, and the associated blood products resulting in transfusion reactions. Methods: We compared transfusion reaction rates, among platelets, plasma, and red blood cells (RBCs) using a retrospective analysis of pediatric patients treated with blood transfusion based on data from the National Center for Children's Health (Beijing, China) by a hemovigilance reporting system from January 2015 to December 2019. Results: Over the past 5 years, 165 reactions were reported, and the overall incidence was 1.35‰ (95% CI: 1.14-1.55‰; 165/122,652); for each separate year, the incidences were 1.25‰ (95% CI: 0.76-1.74‰; 25/20,035; 2015), 1.09‰ (95% CI: 0.65-1.52‰; 24/22,084; 2016), 1.66‰ (95% CI: 1.14-2.18‰; 39/23,483; 2017), 1.36‰ (95% CI: 0.92-1.81‰; 36/26,440; 2018) and 1.34‰ (95% CI: 0.93-1.75‰; 41/30,610; 2019). Transfusion reaction incidents by person included 0.37‰ (95% CI: 0.21-0.53‰; 21/56,815) RBCs, 2.98‰ (95% CI: 2.33-3.64‰; 79/26,496) platelets and 1.65‰ (95% CI: 1.25-2.05‰; 65/39,341) frozen plasma. According to the analysis by blood products, the incidence of transfusion was 0.34‰ (95% CI: 0.20-0.48‰; 23/66,958) for RBCs, 3.21‰ (95% CI: 2.50-3.92‰; 78/24,318.5) for platelets, and 0.94‰ (95% CI: 0.71-1.17‰; 64/67,912) for frozen plasma. Transfusion reactions were most commonly associated with platelets, followed by plasma and RBC transfusions. The types of blood transfusion reactions were mainly allergic reactions (86.67%) and febrile non-hemolytic transfusion reactions (FNHTRs, 4.24%). The disease types of pediatric patients with transfusion reactions were concentrated among those with blood system diseases. A total of 80.61% of children with transfusion reactions had a previous blood transfusion history. Conclusions: Transfusion reactions are still relatively common in pediatric patients, and additional studies are necessary to address the differences in reaction rates, especially allergic and FNHTRs. Robust hemovigilance systems do include a special section dedicated to children will further the understanding of these reactions and trends, and prospective randomized clinical controlled trials may need to be conducted to perform preventive and corrective measures.

Effect of hemoglobin content on cerebral oxygen saturation during surgery for scoliosis in pediatric patients.

BACKGROUND: Although regional cerebral oxygen saturation (rScO2) monitoring has been widely used in clinical practice, the relationship between hemoglobin (dHB) content and rScO2 is incompletely understood. The aim of this study was to analyze the effect of hemoglobin content on rScO2 in pediatric patients undergoing general anesthesia for correction of scoliosis. METHODS: Ninety-two pediatric patients aged 3 to 14 years undergoing scoliosis correction surgery were enrolled. Continuous monitoring of bilateral regional cerebral oxygen saturation by near-infrared spectroscopy (NIRS, CASMED, USA) was performed after entering the operation room. rScO2 was recorded when the patients entered the operating room (T0, baseline), after anesthesia induced intubation (T1), and after radial artery puncture (T2). The lowest value of rScO2 during surgery was also recorded. The arterial blood pressure (ABP), heart rate (HR), pulse oxygen saturation (SpO2), end tidal carbon dioxide partial pressure (PetCO2) were continuously recorded. Patients were classified as low rScO2 or high rScO2 group according to whether the lowest intraoperative rScO2 was 15% lower than the baseline value. An analysis and comparison of differences in hemoglobin content in these two groups was carried out. RESULTS: The preoperative hemoglobin-postoperative hemoglobin of patients in the high rScO2 group was significantly lower than that in the low rScO2 group (t = - 7.86, p < 0.01), the amount of bleeding during the operation was also less than that in the low rScO2 group (t = - 6.05, p < 0.01), and the systolic pressure of patients was higher than that in the low rScO2 group (t = 4.27, p < 0.01). CONCLUSIONS: The decrease in hemoglobin level which occurs during surgery leads to a decrease in cerebral oxygen saturation. In order to ensure patient safety during surgery, it is necessary to carry out volume management and appropriate transfusion and fluid replacement in a timely manner. TRIAL REGISTRATION: Chinese Clinical Trial Registry, ChiCTR1800016359 . Registered 28 May 2018.

Prevalence and intervention of preoperative anemia in Chinese adults: A retrospective cross-sectional study based on national preoperative anemia database.

BACKGROUND: Preoperative anemia is an important pillar of perioperative patient blood management. However, there was no literature comprehensively described the current situation of preoperative anemia in China. METHODS: We conducted a national retrospective cross-sectional study to assess the prevalence and intervention of preoperative anemia in Chinese adults. Data were from the National Preoperative Anemia Database based on hospital administration data from January 1, 2013 to December 31, 2018. FINDINGS: A total of 797,002 patients were included for analysis. Overall, 27.57% (95% CI 27.47-27.67) of patients had preoperative anemia, which varied by gender, age, regions, and type of operation. Patients who were female, age over 60 years old, from South China, from provinces with lower per capita GDP, underwent operations on the lymphatic and hematopoietic system, with laboratory abnormalities were more likely to have a high risk of preoperative anemia. Among patients with preoperative anemia, 5.16% (95% CI 5.07-5.26) received red blood cell transfusion, 7.79% (95% CI 7.67-7.91) received anemia-related medications such as iron, erythropoietin, folic acid or vitamin B12, and 12.25% (95% CI 12.10-12.40) received anemia-related therapy (red blood cell transfusion or anemia-related medications) before operation. The probability of preoperative RBC transfusion decreased by 54.92% (OR 0.46, 95% CI 0.46-0.47) as each 10-g/L increase in preoperative hemoglobin. Patients with preoperative hemoglobin less than 130 g/L was associated with longer hospital stay and more hospital costs. Patients with severe preoperative anemia given iron preoperatively had lower intra/post-operative RBC transfusion rate, shorter length of stay and less hospitalization costs, but no similar correlation was found in patients with mild and moderate preoperative anemia and patients given erythropoietin preoperatively. INTERPRETATION: Our present study shows that preoperative anemia is currently a relatively prevalent problem that has not been fully appreciated in China. More researches will be required to optimize the treatment of preoperative anemia. FUNDING: National Natural Science Foundation of China and the Logistics Support Department of the Central Military Commission.

The Immune System in Transfusion-Related Acute Lung Injury Prevention and Therapy: Update and Perspective.

As an initiator of respiratory distress, transfusion-related acute lung injury (TRALI) is regarded as one of the rare complications associated with transfusion medicine. However, to date, the pathogenesis of TRALI is still unclear, and specific therapies are unavailable. Understanding the mechanisms of TRALI may promote the design of preventive and therapeutic strategies. The immune system plays vital roles in reproduction, development and homeostasis. Sterile tissue damage, such as physical trauma, ischemia, or reperfusion injury, induces an inflammatory reaction that results in wound healing and regenerative mechanisms. In other words, in addition to protecting against pathogens, the immune response may be strongly associated with TRALI prevention and treatment through a variety of immunomodulatory strategies to inhibit excessive immune system activation. Immunotherapy based on immune cells or immunological targets may eradicate complications. For example, IL-10 therapy is a promising therapeutic strategy to explore further. This review will focus on ultramodern advances in our understanding of the potential role of the immune system in TRALI prevention and treatment.

Predicting the postoperative blood coagulation state of children with congenital heart disease by machine learning based on real-world data.

BACKGROUND: Postoperative blood coagulation assessment of children with congenital heart disease (CHD) has been developed using a conventional statistical approach. In this study, the machine learning (ML) was used to predict postoperative blood coagulation function of children with CHD, and assess an array of ML models. METHODS: This was a retrospective and data mining study. Based on the samples of 1,690 children with CHD, and screening data based on demographic characteristics, conventional coagulation tests (CCTs) and complete blood count (CBC), with a precise data selection process, and the support of data mining and ML algorithms including Decision tree, Naive Bayes, Support Vector Machine (SVM), Adaptive Boost (AdaBoost) and Random Forest model, and explored the best prediction models of postoperative blood coagulation function for children with CHD by models performance measured in the area under the receiver operating characteristic (ROC) curve (AUC), calibration or Lift curves, and further verified the reliability of the models with statistical tests. RESULTS: In primary objective prediction, as decision tree, Naive Bayes, SVM, the AUC of our prediction algorithm was 0.81, 0.82, 0.82, respectively. The accuracy rate of the overall forecast has reached more than 75%. Subsequently, we furtherly build improved models. Among them, the true positive rate of the AdaBoost, Random Forest and SVM prediction models reached more than 80% in the ROC curve. These overall accuracy rate indicated a good classification model. Combined calibration curves and Lift curves, the better fit is the SVM model, which predicted postoperative abnormal coagulation, Lift =2.2, postoperative normal coagulation, Lift =1.8. The statistical results furtherly proved the reliability of ML models. The age, sex, mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), white blood cell count (WBC) and platelet count (PLT) were the key features for predicting the postoperative blood coagulation state of children with CHD. CONCLUSIONS: ML technology and data mining algorithms may be used for outcome prediction in children with CHD for postoperative blood coagulation state based on the bulk of clinical data, especially CBC indictors from the real world.

[Evaluation and Comparison of Thromboelastography and Conventional Coagulation Tests for Blood Coagulation Function in Children with Henoch-Schönlein Purpura].

OBJECTIVE: To evaluate the coagulation function of children with Henoch-Schönlein purpura (HSP) by thromboelastography (TEG) and conventional coagulation tests (CCTs), and to explore the correlation and consistency of the 2 test methods. METHODS: A total of 468 children with HSP were selected from January 2017 to December 2017 in Beijing Children's Hospital, Capital Medical University. The TEG and CCTs data were analyzed to evaluate coagulation function of children with HSP, meanwhile, the coagulation results were analysed the superiority of the 2 test methods was compared by Pearson correlation and Kappa consistency analysis. RESULTS: There were no clinically significant abnormalities practically in HSP children by TEG and CCTs analysis, except for D-dimer level was elevated (t=9.15, P＜0.001). There were no significant changes for coagulation data from, sex comparison of HSP children (P＞0.05 all), but the coagulation reaction time (R), blood clot formation time (K), α-Angle, CI value, fibrinogen, D-dimer and anti-thrombin III in HSP children with different age groups showed difference (P＜0.05 all), and the blood in children aged 0-2 years old tended to be hypercoagulable. The TEG indexes demonstrated no significant difference in coagulation function of children with HSP each other (P＞0.05). However, CCTs data showed that the blood in children with severe kidney involvement were hypercoagulable. Comparision results of the correlation and consistency of TEG and CCTs in detecting coagulation function of HSP children showed that R was weakly correlated with prothrombin time (PT), International Normalized Ratio (INR) and activated partial thromboplastin time (APTT). There were weak correlation between K, α-Angle and Fib (0.1＜|r|＜0.4 all). There was no obvious consistency between them each other (kappa＜0.4 all). CONCLUSION: The overall changes in coagulation function in children with HSP are not obvious, but the hyperfibrinolysis in hypercoagulable state may exists. Furthermore, younger age and severe kidney involvement may cause hypercoagulation in HSP children. The weakly correlation and consistency of TEG and CCTs in detecting coagulation function of HSP children are furtherly confirmation, and the 2 test methods may be irreplaceable.

[Establishment of method collecting peripheral blood hematopoietic stem/progenitor cells from infants].

The aim of this study was to explore a safe method collecting peripheral blood stem/progenitor cell (PBSPC) from the infants of body weight less than 20 kg by using the COBE Spectra Blood Cell Separator through Auto-PBSC procedure. After washing tube by normal saline, one unit of irradiated RBC was infused into the apheresis set. When the collection terminated, only the concentrated RBC in the apheresis set was returned to the infant. The peripheral mononuclear cells (PBMNCs) and CD34+ cells were counted, the cell viability was determined. The results showed that 13 PBSPC collections were carried out successfully from 7 infants of body weight<20 kg. The average count of MNCs was 4.44x10(8)/kg [(3.46-6.45)x10(8)/kg], the CD34+ count was 2.20x10(6)/kg [(1.34-3.79)x10(6)/kg] and the cell viability was 98.45% (97%-100%) respectively. The vital signs of all the infants went smoothly during collection of PBSPCs. In conclusion, with the aid of COBE Spectra blood cell separator and other measures, the collection of PBSPCs from infants of body weight<20 kg is safe and effective, the PBMNCs containing enough PBSPC can be harvested for transplantation.

[Frequency of ABO type IgM antibody in 276 infants younger than six months].

The aim of study was to explore the frequency of ABO type IgM antibody in infants younger than six months. 309 hospitalized infants younger than six months were selected at first and their EDTA K(3) anticoagulant blood samples were taken. All the infants were divided into five groups: neonates within 1 week as group I; neonates aged 8 to 14 days as group II; neonates aged 15 days to 1 month as group III; infants aged two to 3 months as group IV and infants aged 4 to 6 months as group V. The monocolonal anti-A, anti-B serums, A cells, B cells and O cells were utilized to carried out the blood typing with tube test. The results indicated that from 309 samples tested 33 AB type sample were excluded. Out of the remains of 276 samples, 29 of 46 samples in group I were positive and with the ABO type consistent rate 63% (29/46); 41 of 64 samples in group II were positive and with the ABO type consistent rate 64% (41/64); 47 of 74 samples in group III were positive and with the ABO type consistent rate 63% (47/74); 28 of 45 samples in group IV were positive and with the ABO type consistent rate 62% (28/45); 40 of 47 samples in group V were positive and with the ABO type consistent rate 85%. It is concluded that the ABO type IgM antibody appear in most infants younger than six months and these IgM antibodies may be regarded as the important evidence for ABO typing in infants.

[Collection of peripheral blood stem cells from ABO incompatible allogeneic donors by using blood cell separator].

To evaluate the yield of the blood cell separator for collection of peripheral blood stem cells (PBSC) from ABO major and (or) minor incompatible allogeneic donors and the feasibility of PBSC component infusion to the recipients without removal of erythrocytes or plasma, the Cobe Spectra (Version 6.1) blood cell separator was utilized to collect PBSC component from 9 allogeneic donors. Of all the donors, 4 were ABO major incompatible, 2 were minor incompatible and the other 3 were both major and minor incompatible to corresponding recipients. In each cycle, different amount of PBSC component was harvested, and the variable volume plasma chased the cells into the bag was adjusted according to the ABO incompatibility. The nucleated cell count, percentage of mononuclear cell, number of CD34(+) cell and percentage of viable cell (trypan blue excluding rate) in the component were detected. At the time of infusion, a series of protective measures to the renal function of recipients were taken. The results showed that apheresis was twice performed on these eight donors to collected enough PBSC for transplantation or cryopreservation, except one apheresis was enough for cell amount needed by transplantation, as the donor's body weight was much heavier than that of the recipient. Altogether 17 apheresises were performed, the mean yield of nucleated cells was 3.77 x 10(10), in which 97% to 99% were mononuclear cells (MNC). The harvested number of CD34(+) cell was 8.62 x 10(6)/kg. All the trypan blue exclusion rate was 100%. In ABO major incompatible or both major and minor incompatible component, there were 8 - 10 ml packed erythrocytes; in ABO minor incompatible component, there were 80 - 120 ml of plasma. These components were infused into the recipients without removal of erythrocytes or plasma and no haemolytic reaction was observed in any recipient, and their hematopoietic functions soon recovered. Results suggest that enough PBSC can be acquired by using blood cell separator Cobe Spectra (Version 6.1), with the modified separation factors, and the collected PBSC component can be safely infused into the ABO incompatible recipients without removal of erythrocytes or plasma.

[Slide platelet aggregation test used as a monitor for patient treated with anti-pletelet drugs].

The aim was to verify the effectiveness of slide platelet aggregation test (SPAT) to monitor the inhibition effect of anti-platelet drugs. A group of eight healthy volunteers was examined for SPAT value and T(50) (time necessary for reaching 50% of total aggregation) induced by ADP, arachidonic acid (AA) and cationic propyl gallate (c-PG) respectively before and after administration of ASA in dose of 100 mg/day for 3 days. The group of 41 inpatients at the Department of Cardiovascular Disease treated with anti-platelet drugs and the group of 327 healthy blood donors were also examined for SPAT. The SPAT value of healthy volunteer samples stored at room temperature were measured hourly for four hours. The results showed that: (1) no significant difference was detected between the T(50) before and after ASA administration in health volunteer group when ADP was used as inducer, but a significant difference was detected in this group when AA or c-PG was used as inducer. There was significant linear correlation between SPAT value and T(50) induced by c-PG in health volunteer group before and after administration of ASA (r = 0.998, P = 0.000); (2) there was no significant difference between the SPAT value of health volunteer group before administration of ASA and the SPAT value of health blood donors group (P = 0.853), but there was a significant difference between the SPAT values before and after administration of ASA in health volunteer group (P = 0.000). There was significant difference when the SPAT value of the inpatients treated with anti-platelet drugs was compared with that of healthy blood donor group and with that of health volunteer group before and after administration of ASA (P = 0.000). The cut-off value of SPAT in health blood donor group was 44.6 +/- 11.7 seconds, reference value was from 21.1 seconds to 68.0 seconds; (3) there was no significant difference between SPAT values when platelets samples stored at room temperature for 1, 2, 3, 4 hours (P = 0.815). In conclusion, SPAT can rapidly monitor the inhibition effect of anti-platelet drugs and SPAT may have the similar clinic value with T(50) induced by c-PG.

[Effects of preparation and quality control of cryopreserved platelets].

The purpose of this study was to establish a set of techniques for cryopreservation of platelets with dimethylsulphoxide (DMSO) to insure high quality of cryopreserved platelet. The methods were as following: (1) DMSO was filtered in stead of being sterilized before infusion into the bag with platelets. (2) The whole blood was centrifuged immediately after blood collection and the attached tube was tied on the top of the bucket. (3) The related centrifugal force was 480 x g, the accelerating and braking grades of the centrifuge for acceleration and deceleration were 9 and 4 respectively. (4) The flow rate of platelet rich plasma (PRP) could not be too high, 80 - 100 ml PRP should be harvested at 1 minute or so. The infusion rate of DMSO into the PRP was 1 ml/min. After the infusion of DMSO, the PRP bag must be put into the -80 degrees C ultra low freezer at once to make the product to be freezed as soon as possible. The cryopreserved platelet should be thawed in the cycling warm water at the temperature of 38 - 40 degrees C. (5) After thawing of platelet, the platelet, red blood cell and white blood cell were counted, and the bacteria culturing, tests for HBsAg, anti-HCV, anti-HIV, TP and ALT were carried out. The results showed that altogether 14 800 units of cryopreserved platelets were prepared including 80 units collected with blood cell separator, of which quality control was accomplished in 300 units. The manually collected platelet mean count >/= 2.4 x 10(10)/unit, while the apheresis platelet count >/= 2.5 x 10(11)/unit. The yield was over 70%. The contaminated red and white blood cells were

[Determination and comparison of anti-SARS antibody in children and adults].

To investigate the positive rate of anti-SARS antibody in children and adults without SARS, 197 paediatric patients under 14 years old from inpatient and outpatient department of our hospital, 156 healthy children pupils from primary school, 453 adult patients over 18 years old from inpatient and outpatient department of our hospital and other 502 healthy adult blood donors were selected. Anti-SARS antibodies were determined by anti-SARS specific antibody detection kit and ELISA method. The results showed that both the positive rates of IgG antibody in paediatric patients and healthy children were about 2% (4/197 and 3/156), while the positive rates in adult patients and healthy adults were about 0.2% (1/453 and 1/502). The difference between the positive rates of children and adults was significant (chi(2) = 11.61, P < 0.001). IgM antibody was negative in all the samples. It is concluded that the anti-SARS IgG antibody positive rate in children was obvious higher than that in adults. This may be the cause why the cases with SARS in children is much less than in adults.

[Qualitative analysis of batch preparing cryopreserved fresh platelet rich plasma].

To evaluate the efficiency and effectiveness of batch preparing cryopreserved fresh platelet-rich plasma (cryo-FPRP) derived from the volunteer donors, platelet count (Plt), mean platelet volume (MPV), platelet distribution width (PDW), plasma pH, plasma lactic acid concentration, and lactic dehydrogenase (LDH) concentration, germiculture, CD62p positive rate, PAC-1 positive rate, and the fluorescence intensity of platelet GPIb-IX-V were detected in ACD whole blood, fresh platelet-rich plasma (FPRP), FPRP with 5% dimethyl sulphoxide DMSO (DMSO-FPRP), and thawed cryopreserved FPRP (cryo-FPRP); the procoagulant activity of FPRP and cryo-FPR was determinated. The results showed that (1) 70 percentage of platelet were separated from the whole blood into FPRP, and the counts of residual erythrocyte and leucocyte were below 1 x 10(9), and below 1 x 10(7) per unit respectively. (2) The plasma pH, lactic acid concentration and PAC-1 positive rate retained a stable level during the preparing, storing and thawing process. (3) Plasma LDH concentration, platelet CD62p positive rate and GPIb-IX-V concentration in platelet surface were enhanced significantly after being frozen and thawing. (4) The plasma clotting time induced by cryo-FPRP were significantly shorter than that induced by FPRP. It is concluded that: (1) The batch platelet preparing process can efficiently obtain platelet from whole blood donated by volunteer, and the process didn't activate the platelet. (2) Cryopreservation can prevent lactic acid accumulation, pH reduce and activation of GPIIb/IIIa. (3) The membrane of partial platelets are affected by freezing and thawing. (4) The density of GPIb-IX-V complexes in platelet surface and its procoagulant activity are enhanced significantly after the FPRP freezing and thawing process.

[Detection of the anti-SARS-coronavirus specific antibody levels in 156 SARS patients].

The objective of this study was to explore the development of IgG and IgM against SARS CoV and characteristics of changes of antibody titers in patients with severe acute respiratory syndrome (SARS) and to search the opportunity for collecting specific anti-serum from convalescent patients with SARS. The anti-SARS-coronavirus specific antibody levels in 156 SARS patients were measured with ELISA. The results showed that the total positive rates of IgG and IgM were 75.6% and 41.7% respectively, and the negative rate of both IgG and IgM was 23.7%. The average titers of IgG and IgM antibody in positive samples were 18.23 +/- 24.72 and 2.18 +/- 1.13, respectively. There was no significant correlation between the titers of IgG/IgM and sex, age, course of diseases and duration of body temperature recovery. It was concluded that not all SARS patients could produce the anti-SARS-coronavirus specific antibody. The titers of the anti-body are diversified even if the antibodies have been emerged in them. In order to obtain effective anti-serum, the titers of antibody must be tested just before collection of convalescent serum, and it ensures the therapeutic effect and provides a measurable index for clinical transfusion.