[Objective] To study the relationship between the expression intensity of HLA-Ⅰ platelet antibodies in patients with platelet transfusion refractoriness (PTR) and platelet cross-matching, and to further evaluate other factors in order to provide relevant data support for improving platelet transfusion efficiency and optimizing platelet transfusion regimens. [Methods] Luminex single antigen flow cytometry was used to detect platelet specific antibodies in 35 patients with hematological disease. Subsequently, the Capture-P method was employed to perform 102 crossmatchings between plasma with HLA-Ⅰ antibodies and platelets with known HLA-Ⅰ genotypes. The cross-matching results were assessed and the clinical transfusion outcomes were tracked. [Results] The positive detection rate of HLA-Ⅰ and HPA antibodies in this study was 48.6% (17/35). The negative rate of cross-matching in 102 cases was 37.3% (38/102). Multiple factors affect platelet cross-matching, such as HLA-Ⅰ antibody expression level and antibody type, antigen expression level, cross-reactivity group and eplets. Among them, the expression level and antibody type of HLA-Ⅰ antibody are the main influencing factors. However, the effectiveness of clinical platelet transfusion is not completely determined by the compatibility of platelet cross-matching. [Conclusion] In addition to avoiding strong positive HLA-Ⅰ antibodies, clinical matching should also be vigilant against the serological cross-incompatibility caused by weak positive HLA-Ⅰ antibodies. It may be necessary to establish HLA-Ⅰ low expression antigen database as a better alternative platelet donor selection strategy, and gradually explore the effectiveness of ‘low expression mismatch’ strategy for clinical platelet transfusion.

Objective To investigate the diagnostic value of dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI)parameters for cognitive dysfunction in first-episode stroke,thereby providing reference for the early clinical assessment of the risk of cognitive dysfunction in stroke and formulation of intervention programs.Methods A total of 122 patients with first-episode stroke were enrolled and divided into occurrence group(n=53)and non-occurrence group(n=69)according to whether they had cognitive dysfunction.Additionally,53 patients with non-cerebrovascular cognitive dysfunction were selected as control group.All patients underwent DCE-MRI examination after admission.The 3 groups and patients with different degrees of cognitive dysfunction were compared for DCE-MRI parameters,including interstitium-to-plasma rate constant(Kep),volume transfer constant(Ktrans),volume fraction of extravascular extracellular space(Ve),and volume fraction of plasma(Vp).The correlations of DCE-MRI parameters with the degree of cognitive dysfunction were analyzed,along with their diagnostic value for cognitive dysfunction and evaluation value for the risk of cognitive dysfunction after first-episode stroke.Results Both occurrence group and non-occurrence group had higher levels of Ktrans,Ve and Vp than control group,and these parameters were higher in occurrence group than non-occurrence group(P<0.05).Ktrans,Ve and Vp of patients with different degrees of cognitive dysfunction differed significantly(P<0.05),and they were increased significantly with the aggravation of cognitive dysfunction.Ktrans,Ve and Vp were all positively correlated with the degree of cognitive dysfunction (P<0.05). The AUC for the combined diagnosis using Ktrans, Ve and Vp was 0.921, significantly higher than single index (P<0.05). The risks of cognitive dysfunction in first-episode stroke patients with higher levels of Ktrans, Ve and Vp were 3.077, 1.944 and 2.313 times of the low-level, respectively. Conclusion DCE-MRI can be used to diagnose cognitive dysfunction in first-episode stroke, providing reference for early clinical prediction of cognitive dysfunction after stroke.

Objective To investigate the infection of human parvovirus B19 in Suzhou voluntary blood donors under the current blood screening model. Methods A total of 893 blood donor samples from September to December 2022 were randomly collected. Samples were tested to determine the seroprevalence (anti-B19 IgG and IgM) of B19 antibodies by enzyme-linked immunosorbent assay(ELISA), and B19 DNA of positive samples was further detected by real-time polymerase chain reaction(PCR) assay. Results Among 893 samples, the total seroprevalence of B19 antibody was 20.7% (185/893), with anti-B19 IgG and IgM positive rate at 19.4% (173/893) and 1.9% (17/893), respectively, showing significant difference (P<0.05). No difference in the positive rates of B19 IgG and IgM (20.1%, 1.5% vs 18.0%,2.6%) was noticed by gender(P>0.05). The prevalence of anti-B19 IgG statistically increased with age (P<0.05), while there was no difference in the prevalence of anti-B19 IgM (P>0.05). No statistical difference was not found in anti-B19 IgG and IgM samples among different blood groups. The anti-B19 IgG in repeated blood donors was higher than that in first-time donors(21.5% vs 15.9%)(P<0.05) while there was no difference in the positive rate of IgM antibodies (P>0.05). Three cases were found to be positive for B19 DNA in the B19 antibody positive samples, with the positive rate at 1.6%(3/185). Conclusion Although the prevalence of B19 infection in Suzhou was lower than that in other areas and was mostly past infection, there was still a certain proportion of persistent infection and acute infection, which posed the potential risk of blood transfusion transmission. Therefore, attention should be paid to blood transfusions, especially for the high-risk and susceptible groups.

【Objective】 To analyze differences of eplets between the patient who generated HLA allele-specific antibodies after platelet transfusion with donors. 【Methods】 The HLA genotypes of the patient and donors were detected by PCR-SBT, and the Luminex single antigen beads coating was used to screen HLA-Ⅰ antibodies in the patient’s serum. HLA Matchmaker was utilized to analyze different amino acids and eplets. 【Results】 The patient carried HLA-A^*02∶03 allele, and HLA-A2 antibodies were found in his serum after platelet transfusion (A^*02∶01, A^*02∶06, and A^*02∶07). Sequence alignment showed that the patient′s A^*02∶03 has a difference in position 149, which resulted in a different eplet between A^*02∶03 and A^*02∶01, A^*02∶06, A^*02∶07 and then induced the production of antibodies. 【Conclusion】 HLA antibodies are specific for HLA epitopes that have structural differences due to amino acid differences between HLA alleles, suggesting that high-resolution typing of HLA-A, -B need to be conducted in patients and donors, and the acceptable mismatch of HLA should be determined based on epitopes rather than antigens, so as to reduce alloimmune response and improve platelet count after transfusion.

Humans ; COVID-19/genetics* ; SARS-CoV-2/genetics* ; Clustered Regularly Interspaced Short Palindromic Repeats/genetics* ; CRISPR-Cas Systems/genetics* ; RNA, Viral/genetics*

【Objective】 To study the incidence and specificity of platelet antibody in blood donors in Suzhou, analyze the distribution characteristics of platelet antibody in blood donors in this area, and explore the significance of platelet antibody detection in blood donors to reduce the adverse reactions toplatelet transfusion in clinical. 【Methods】 Platelet antibody detection was performed in 2178 blood donors in this area by solid-phase immunosorbent assay. The antibody specificity of the positive samples was analyzed by commercial kit, and the anti-CD36 antibody positive samples were further identified by flow cytometry and gene sequencing. 【Results】 Twelve positive samples were detected by platelet antibody screening, with a positive rate of 0.55%(12/2 178), including 5 males (0.33%, 5/2 178)and 7 females(1.06%, 7/2 178). Among the positive samples, anti-HLA-Ⅰ antibody was identified in 2 cases, anti-CD36 antibody in 1 case, and the antibody specificity was not identified in the other 9 cases. In one case, the positive rate of anti-HLA-Ⅰ antibody PRA was 31.31%(31/ 99), which was mainly specific to anti-B15, anti-B35 and anti-B40. The positive rate of anti-HLA-Ⅰ antibody PRA in the other case was 45.45%(45/ 99), which was mainly specific to anti-A2, anti-A11, anti-A24, anti-A29, anti-A33, anti-A66, anti-B15 and anti-B35. The blood donor with anti-CD36 antibody was type I CD36 deficiency, and 329_330delAC mutation occurred in exon 5. 【Conclusion】 Through antibody screening and specificity identification, the positive rate of platelet antibody in females was significantly higher than that in males(P<0.05). In addition to the common anti-HLA-I antibodies, anti-CD36 antibody was also detected in type I CD36 deficient blood donor. Therefore, the detection of platelet antibodies in blood donors is of certain clinical significance to reduce the adverse reactions to blood transfusion caused by antibodies in platelet products.

【Objective】 To investigate the expression of CD36 antigen in Suzhou area, analyze the type of antigen deficiency and gene mutation, so as to provide references for the establishment of CD36 negative donor registry in Suzhou. 【Methods】 Anticoagulant whole blood samples (805 cases) were randomly collected from healthy blood donors in Suzhou Blood Center. The expression of CD36 antigen on platelet and monocyte was analyzed by flow cytometry to determine the type of CD36 deficiency. The gene mutation type of platelet CD36 antigen-deficient was performed by genomic DNA sequencing. 【Results】 The CD36 deficiency frequency on platelet was 2.48% (20/805), among which TypeⅠ(lacking CD36 expression both on platelet and monocyte) and TypeⅡ(lacking CD36 expression on platelet only) CD36 deficiency accounted for 10% (2/20) and 90% (18/20), respectively. CD36 gene mutations were found in 10 samples, including 3 cases of 329_330 d^elAC, 1 case of 1228_1239 d^elATTGTGCCTATT and 2 cases of 1163 A>T; 1 case of 329_330 d^elAC+ 1172_1183 d^elTATTGGTCAAGC and 287 G>C+ 329_330 d^elAC heterozygous mutation. In addition, 1 case of 745 A>G and 1 case of 806 C>T mutations were novel, and not yet reported. 【Conclusion】 Results showed that the frequency of CD36 antigen deficiency in Suzhou were similar to that reported in southern China, but the mutation sites were slightly different. The establishment of CD36 negative platelet registry could provide negative platelets for patients with transfusion reactions caused by anti-CD36 antibody and improve the effect of clinical platelet transfusion.

Objective To compare the short-term efficacy of AC TightRope plate and clavicular hook plate in the treatment of acromioclavicular joint dislocation.Methods A retrospective case control study was conducted to analyze the clinical data of 32 patients with acromioclavicular joint dislocation admitted to Yifu Hospital Affiliated to Nanjing Medical University from April 2016 to December 2017.There were 23 males and 9 females,aged 26-61 years [(43.5 ±9.5)years].According to Rockwood classification,there were 23 patients with type Ⅲ and 9 patients with type Ⅴ.The patients were divided into AC TightRope group and clavicular hook plate group according to different treatment methods.There were 17 patients in AC TightRope group,including 12 males and 5 females,aged (42.6 ± 10.3)years.There were 15 patients in clavicular hook plate group,including 11 males and 4 females,aged (44.5 ± 8.9)years.The incision length,operation time,intraoperative blood loss,hospitalization time,postoperative visual analogue scale (VAS) of the affected shoulder,functional recovery of shoulder joint and complications were compared between the two groups.Results All patients were followed up for 6-26 months,with an average of 15 months.There was no significant difference between the two groups in hospitalization time (P ＞ 0.05).In the AC TightRope group and clavicular hook plate group,the operation time was (41.5 ±4.2)minutes and (60.1 ± 4.2) minutes,respectively (P ＜ 0.01);the incision length was (3.6 ± 0.3) cm and (10.1 ± 0.6) cm,respectively (P ＜ 0.01);the intraoperative blood loss was (45.3 ± 11.1) ml and (78.3 ± 16.0) ml,respectively (P ＜ 0.01);the postoperative VAS of the shoulder was (1.9 ± 0.5) points and (3.1 ± 0.7) points,respectively (P ＜ 0.05);the excellent and good rate of postoperative recovery of shoulder joint function was 100％ (17/17) and 67％ (10/15),respectively (P ＜0.01).There were no complications such as surgical incision infection,intraoperative neurovascular injury or condylar fracture during the perioperative period.No serious postoperative complications such as internal fixation loosening,loss of reduction or recurrence of dislocation were found in both groups.Conclusion For acromioclavicular joint dislocation,AC TightRope can obtain good clinical effect and has obvious advantages in operation time,incision length and blood loss,with lower incidence of shoulder pain and better functional recovery compared with clavicular hook plate.

Objective: To compare the value of two 3D imaging reconstruction methods for left atria and pulmonary vein on guiding the catheter ablation for atrial fibrillation (AF). Methods: From January 2014 to January 2017, a total of 100 drug refractory paroxysmal AF patients were divided into left atria direct angiography group (n=50), and indirect angiography group (n=50). 3D CARTO system was applied for mapping and guiding the ablation procedure. Patients assigned to direct angiography group were treated as follows: intraoperative puncture of atrial septum, inject contrast agent directly into the left atrium, conduct left atrial and pulmonary venous rotation angiography, reconstruct three-dimensional image, integrate the image into real-time X-ray system to facilitate circumferential pulmonary vein isolation. Patients assigned into the indirect angiography group were treated as follows: inject contrast agent through the right ventricle, conduct delayed rotation angiography of the left atria and pulmonary vein to guide circumferential pulmonary vein fixation and ablation. The left atrial and pulmonary venous image acquisition, the operation and X-ray exposure time, the success rate and the incidence of complication of the two groups were compared. The patients were followed up for 3-6 months. Results: General clinical characteristics of the two groups were similar(all P>0.05). Ablation was successful in all 100 patients. The operation time[(112.0±21.4)min vs. (134.0±24.3)min]and X-ray exposure time((10.7±4.7)min vs. (15.8±5.2)min)were significantly lower in direct angiography group than in indirect angiography group (both P<0.01). There was no significant difference between the two groups in the immediate (86%(43/50) vs. 82%(41/50), P=0.59) and short-term (76%(38/50) vs. 72%(36/50), P=0.65) success rate and complication rate (1 aneurysm in the direct angiography group, 1 pericardial tamponade in the indirect angiography group). In-hospital mortality was zero percent. Conclusion It is safe and effective method to guide the radiofrequency catheter ablation of paroxysmal atrial fibrillation by reconstruction 3D image of left atrium and pulmonary vein. Compared with indirect angiography group, direct angiography group can improve the imaging quality of left atrium and pulmonary vein, decrease the X-ray exposure time of the ablation procedure.

Objective To investigate the feasibility of using leukocytes that were filtered out by LeukoReduction System ( LRS) to replace conventional human peripheral blood leukocytes in experimental researches and to comparatively analyze the differences between them in vitro biological functions and pheno-types of T cells. Methods Mononuclear cells were isolated from LRS-separated leukocytes and whole blood sample that collected from the same person by using Ficoll. Fluorescence-activated cell sorting ( FACS) was performed to analyze the phenotypes of T cells. CD3+T cells were sorted out by using magnetic beads. The T cells that were collected by using two different ways were incubated with anti-CD3 and anti-CD28 antibodies and IL-2 in vitro for 10 days. Several assays including cell counting, FACS and cytometric beads array ( CBA) were performed to comparatively analyze the differences in biological functions and phenotypes of T cells that were isolated by different methods. Results The phenotypes of T cells isolated from LRS filter and whole blood sample were highly similar at the initial stage. The sorting rate of CD3+T cells form LRS filter reached a high level and met the requirements for experimental researches. No statistically significant differ-ences in cell count, phenotype, expression of costimulatory molecules and cytokine secretion were observed between T cells isolated from LRS filter and whole blood sample. Conclusion This study suggested that the T cells isolated from LRS filter could be used as an alternative to whole blood T cells for fundamental resear-ches since they were similar in cell vitality, phenotype and biological functions. It provided a new way to solve the problem of blood shortage in clinic and scientific research.