[Analysis of the reentry status of blood donors with reactive bloodborne pathogen screening markers in Hangzhou City]

Objective: To explore the reentry rate of reactive blood donors in the bloodborne pathogen infection screening in Hangzhou City, and analyze the donation behavior of those who successfully returned. Methods: A retrospective analysis of the return data of blood donors with reactive bloodborne pathogen screening markers was conducted at Zhejiang Provincial Blood Center from June 2017 to May 2022. The reentry process for blood donors with reactive bloodborne pathogen screening markers in Hangzhou City is as follows: after the initial screening period of 6 months, donors can voluntarily apply for return to the blood center. Samples are collected and subjected to routine enzyme-linked immunosorbent assay (ELISA) screening for HBsAg, anti-HCV, HIV Ab/Ag, and anti-TP, as well as a single nucleic acid (HIV/HCV/HBV) test. For samples that show non-reactivity in both ELISA and nucleic acid tests, serum biomarker testing for the reasons of exclusion is performed using chemiluminescence immunoassay (CLIA), and those with non-reactivity are allowed to return. Results: A total of 4 583 reactive blood donors who met the criteria for re-entry applied for reentry, out of which 475 applications were received from donors in the Hangzhou area. Among these, 279 donors were successfully readmitted, resulting in a success rate of 58.74% (279/475). By the end of December 2021, out of the 174 donors who successfully returned, 114 donors chose to donate again. They collectively donated 39 530 ml of whole blood and 1 147.2 therapeutic doses of platelets. Among these, 21 donors once again showed reactivity for pathogen infection biomarkers, accounting for 18.42% (21/114). Conclusion: The reentry strategy has somewhat mitigated the attrition of blood donors. Nevertheless, there are instances where donors who were successfully readmitted show reactivity once more in the screening for pathogen infection biomarkers.

Type, Timing, and Diversity of Complementary Foods Among Native Hawaiian, Pacific Islander, and Filipino Infants

Prevention is the recommended strategy for addressing childhood obesity and may be particularly important for minority groups such as Native Hawaiians, Pacific Islanders, and Filipinos (NHPIF) who display poorer health outcomes than other race/ethnic groups. Complementary feeding is a critical milestone in the first 1,000 days of life and plays a critical role in growth and eating habit formation. This cross-sectional study recruited NHPIF infants between 3 - 12 months of age residing on O'ahu, Hawai'i to examine timing and types of complementary foods introduced first as well as the dietary diversity of those infants 6 - 12 months of age. Basic demographic information and early feeding practices were assessed via online questionnaire. Diet was evaluated using the image-based mobile food record completed over 4-days. Images were evaluated to derive the World Health Organization's minimum dietary diversity (MDD) score. Data were analyzed using descriptive statistics and linear regressions. Seventy participants completed the study with a majority being between the ages of 6 - 12 months (n=56). About half of the participants were provided a complementary food prior to 6 months of age with the most common first complementary food being poi (steamed, mashed taro). Grains were the most commonly reported food group while the high protein food groups was the least commonly reported. Approximately 25% of infants 6 - 12 months of age met MDD all four days. Meeting MDD was significantly associated with age. Findings illuminate opportunities for improvement (eg, delayed introduction) and for promotion (eg, cultural foods) in NHPIF complementary feeding.

Characterization of a novel allelic variant in HLA-B*40 lineage, HLA-B*40:298:02, by cloning and sequencing

A novel allelic variant in HLA-B*40 lineage, HLA-B*40:298:02, has been identified in an individual of Han ethnicity afflicted with nasopharyngeal carcinoma in Hunan province, southern China. Following polymerase chain reaction-Sanger sequence-based typing (PCR-SBT), this new variant was further confirmed by two distinct strategies of cloning and sequencing. HLA-B*40:298:02 differs from HLA-B*40:298:01 by a single synonymous cytosine substitution at nucleotide position 26 (T→C) in exon 3, which corresponds to codon 99 of the mature HLA-B mRNA molecule. This new allele has an estimated frequency of 0.0002, in about 2,500 sequence-based typed subjects from the same population.

Identification of the novel HLA-B*27:04:06 allele in a Chinese bone marrow donor

HLA-B*27:04:06 differs from HLA-B*27:04:01 by a single-nucleotide substitution at position 396 C > A.

Characterization of a novel HLA-B*39:01:01-related allele, HLA-B*39:130, by cloning and phasing

A novel HLA-B*39:01:01-related variant, HLA-B*39:130, has been identified in a normal individual of Han ethnicity in Hunan province, southern China. Following Sanger polymerase chain reaction-sequence-based typing (PCR-SBT), this new allele was further confirmed by cloning, phasing and sequencing. Aligned with HLA-B*39:01:01, HLA-B*39:130 has a nonsynonymous thymine substitution at nucleotide position 94 in exon 4, resulting in amino acid change from threonine to isoleucine at codon 214 (ACA→ATA) of the mature HLA-BmRNA molecule.

A new MICA allele, MICA*007:07, characterized by cloning and sequencing

A new MICA allelic variant, MICA*007:07, was identified in an individual of Mongol ethnicity in the Inner Mongolia Autonomous Region, northern China. Following polymerase chain reaction-sequence-based typing (PCR-SBT), this new allele was further confirmed by cloning and sequencing. MICA*007:07 differs from MICA*007:01 by a synonymous mutation from G to A at the 2nd nucleotide position in exon 2. MICA*007:07 was linked to HLA-B*27:05.

Characterization of a novel MICA allele, MICA*012:05, by cloning and sequencing

A new MICA allelic variant, MICA*012:05, has been identified in a Chinese Mongolian population. Following polymerase chain reaction-sequence-based typing (PCR-SBT), this new allele was further confirmed by cloning and sequencing. MICA*012:05 was linked to an HLA-A*24-C*01-B*55:02-DRB1*09 haplotype. MICA*012:05 differs from MICA*012:01 by a single synonymous C to T substitution at nucleotide position 269 in exon 3.

Characterization of a new HLA-A allele, HLA-A*02:07:08, by cloning and sequencing

In this report, we present a novel HLA-A*02:07 allele, HLA-A*02:07:08. HLA-A*02:07:08 was identified in an individual of Han ethnicity in Hunan province, southern China. Following polymerase chain reaction-sequence-based typing (PCR-SBT), this new allele was further confirmed by cloning and sequencing. HLA-A*02:07:08 differs from HLA-A*02:07:01 by a single synonymous C to T substitution at nucleotide position 131 in exon 3.

HLA-A, HLA-B, HLA-DRB1 allele and haplotype frequencies in 6384 umbilical cord blood units and transplantation matching and engraftment statistics in the Zhejiang cord blood bank of China

Umbilical cord blood (UCB) is a widely accepted source of progenitor cells, and now, many cord blood banks were established. Here, we analysed the HLA-A, HLA-B and HLA-DRB1 allele and haplotype frequencies, HLA matching possibilities for searching potential donors and outcome of UCB transplantations in Zhejiang cord blood bank of China. A total of 6384 UCB units were characterized for 17 HLA-A, 30 HLA-B and 13 HLA-DRB1 alleles at the first field resolution level. Additionally, B*14, B*15 and B*40 were typed to the second field level. A total of 1372 distinct A-B-DRB1 haplotypes were identified. The frequencies of 7 haplotypes were more than 1%, and 439 haplotypes were <0.01%. A*02-B*46-DRB1*09, A*33-B*58-DRB1*03 and A*30-B*13-DRB1*07 were the most common haplotypes, with frequencies of 4.4%, 3.3%, and 2.9%, respectively. Linkage disequilibrium(LD) analysis showed that there were 83 A-B, 106 B-DRB1, 54 A-DRB1 haplotypes with positive LD, in which 51 A-B, 60 B-DRB1, 32 A-DRB1 haplotypes exhibited a significant LD (P < 0.05). In 682 search requests, 12.9%, 40.0% and 42.7% of patients were found to have 6 of 6, 5 of 6 and 4 of 6 HLA-A, HLA-B and HLA-DRB1 matching donors, respectively. A total of 30 UCB units were transplanted to 24 patients (3 patients not evaluated due to early death); 14 of 21 patients (66.7%) engrafted. This study reveals the HLA distribution and its transplantation application in the cord blood bank of Zhejiang province. These data can help to select potential UCB donors for transplantation and used to assess the scale of new cord blood banking endeavours.

Purification and characterization of an intracellular beta-glucosidase from the protoplast fusant of Aspergillus oryzae and Aspergillus niger

Protoplasts of Aspergillus oryzae 3.481 and Aspergillus niger 3.316 were prepared using cellulose and snail enzyme with 0.6 M NaCl as osmotic stabilizer. Protoplast fusion has been performed using 35% polyethylene glycol 4.000 with 0.01 mM CaCl2. The fused protoplasts have been regenerated on regeneration medium and fusants were selected for further studies. An intracellular beta-glucosidase (EC 3.2.1.21) was purified from the protoplast fusant of Aspergillus oryzae 3.481 and Aspergillus niger 3.316 and characterized. The enzyme was purified 138.85-fold by ammonium sulphate precipitation, DE-22 ion exchange and Sephadex G-150 gel filtration chromatography with a specific activity of 297.14 U/mg of protein. The molecular mass of the purified enzyme was determined to be about 125 kDa by sodium dodecyl sulphate-polyacrylamide gel electrophoresis. The enzyme had an optimum pH of 5.4 and temperature of 65 degrees C, respectively. This enzyme showed relatively high stability against pH and temperature and was stable in the pH range of 3.0-6.6. Na+, K+, Ca2+, Mg2+ and EDTA completely inhibited the enzyme activity at a concentration of 10 mM. The enzyme activity was accelerated by Fe3+. The enzyme activity was strongly inhibited by glucose, the end product ofglucoside hydrolysis. The K(m) and V(max) values against salicin as substrate were 0.035 mM and 1.7215 micromol min(-1), respectively.

Identification of a novel allele HLA-A*9208 by sequence-based typing

A novel HLA-A*9208 allele was identified in a Chinese individual by polymerase chain reaction sequence-based typing.

[Expression of tissue factor of astrocytes and its signal transductional pathways]

The aim of this study was to observe the expression of tissue factor (TF) of astrocytes in basic culture medium and under the condition stimulated by thrombin and to explore the relevant signal transduction pathways. The results showed that 4-bromo calcium ionophore (A23187) and phorbol 12-myristate 13-acetate (PMA) enhanced significantly the TF expression of astrocytes, but the expression was decreased markedly by trifluoperazine (TFP) and 1-(5-isoquinolinyl sulfonyl)-3-methyl-piperazine (H7) in the basic medium. Thrombin increased significantly the TF expression of astrocytes, which was obviously inhibited by TFP and H7. The results above indicate that astrocytes can express TF activity in the basic medium, which is promoted by thrombin, probably through some pathways involving Ca2+/CaM and protein kinase C (PKC).