Objective: To establish evidence-based, safe and efficient management of HIV-reactive blood donors by investigating safe and feasible assessment strategies for HIV-reactive blood donors based on routine blood screening data. Methods: The data of blood screening, supplementary testing, follow-up and CDC confirmation for HIV-reactive blood donors in our center from 2014 to 2024 were analyzed systematically to confirm HIV infection and identify infection status. Results: There were 1 235 samples (0.13%, 1 235/928 000) reactive in HIV blood screening over the 11-year period. A-mong them, 199 donors (16.11%) in asymptomatic HIV infection (HIV Ag/Ab++&HIV RNA+), 2(0.16%) as acute early HIV infection (HIV Ag/Ab+-&HIV RNA+) and 7(0.57%) as window-period infection (HIV RNA positive only) were confirmed. Donors with the result of HIV Ag/Ab+-&HIV RNA-(single-positive) were all excluded for HIV infection, while 1 in 6 HIV Ag/Ab++&HIV RNA-donors (double-positive) was confirmed to have HIV infection. When HIV Ag/Ab reagents were used continuously before and after the follow-up, it's observed in one reagent that the proportion of negative results in subsequent follow-up in single-positive donors who had negative results in the first sampling was significantly higher than the proportion of negative results in subsequent follow-up in those initially single-positive (P<0.05). But no significant difference was observed in another reagent (P>0.05). When reagents were changed in follow-up, the rate of singlepositive donors with negative results in the first sampling reached 96.7%, which was significantly higher than the negative rate of those without reagent changing in follow-up (P<0.05). Conclusion: Based on the serological and nucleic acid testing results of HIV blood screening, the confirmation of HIV infection and identification of infection status can be achieved accurately and efficiently. All HIV Ag/Ab+-&HIV RNA-donors were confirmed as false positive, and should be maintained their eligibilities for blood donation, but recommended to pass the retest before next donation. Using a different reagent for retesting helps improve the eligible rate. HIV Ag/Ab++&HIV RNA-donors should be deferred permanently due to the risk of true positivity.

Objective: To explore the management of blood donors tested reactive to HCV in blood screening based on confirmation of HCV infection. Methods: Multiple HCV antibody assays, repeating HCV RNA testing, follow-up of blood donors and retesting of archive samples were performed to confirm HCV infection, identify infection status, and exclude false positives in blood donors reactive to HCV in blood screening. Results: From 2011 to 2024, the unqualified rate of HCV detection in blood screening was 2.45‰(2 751/1 122 026). Among these, anti-HCV+-&NAT-accounted for 1.85‰, followed by anti-HCV++ at 0.60‰. The proportion of anti-HCV+-&NAT-and HCV RNA yields was extremely low (0.007‰). The positive rate of anti-HCV+-&NAT-samples tested by electrochemiluminescence method (ELCIA) was approximately 7.5%, differing among reagents (P<0.05). The follow-up of anti-HCV+-&NAT-donors showed that 96.2% (202/210) were false positives, but 51.4% of donors remained anti-HCV+-&NAT-during follow-up. Among them, 8 donors (3.8%) could not be ruled out from HCV infection due to positive retesting by ELCIA. Of the anti-HCV+-&NAT-donors who were reactive at the first follow-up, 86.8% remained anti-HCV+-&NAT-at the second follow-up. The sampling confirmation data showed that all of 260 anti-HCV++ donors were confirmed as anti-HCV positive, and the proportion of false positives or missed detections by NAT was very low. Two occult HBV infections (OBIs) and one HBsAg carrier were identified among the 3 anti-HCV +-&NAT+ donors, and no HCV infection was confirmed in 5 anti-HCV--&HCV RNA + donors. Conclusion: The prevalence of HCV among blood donors in Dalian was about 0.06%, with extremely low proportion of window-period infection and slightly higher proportion of resolved infections than that of current infections. The majority of anti-HCV+-&NAT-were false positive. Blood donors confirmed as false positive should be qualified in blood screening 3 months later before next donation. In order to reduce the false positive results, it was advisable to avoid the same type of supplementary reagents as the initial reagents when performing confirmation.

Objective: To evaluate repeated testing on blood screening platforms in confirmation of non-discriminatory reactive (NDR) samples in nucleic acid testing (NAT). Methods: A total of 102 HBsAg-negative/NAT NDR samples were collected from voluntary blood donors at Dalian Blood Center between January 2021 and December 2023. Repeated testing was performed using two NAT platforms (Cobas s201 and Panther). For the first round of repeated testing, all samples were tested 12 times on each system; for the second round, the samples which were non-reactive or only reactive once in the first round were tested an additional 8 times. Anti-HBc and anti-HBs was detected using electrochemiluminescence assay (ECA). Meanwhile, blood donors were followed up. Results: The proportion of anti-HBc+ in 102 NDR samples was 88.2%. Forty-one samples (40.2%, 41/102) and 7 samples were confirmed HBV DNA+ in first-round and second-round repeated testing, respectively. The cumulative confirmation rate of HBV DNA+ was 47.1% (48/102) after repeated testing. Extra five blood donors detected HBV DNA+ in follow-up were identified as anti-HBc+ occult hepatitis B virus infection (OBI), while no window period infection was observed. Ultimately, there were 53 HBV infected donors confirmed, 46 HBV infection-unconfirmed, and 3 HBV uninfected. No significant difference was observed between the confirmation rate of the first-round testing and the cumulative confirmation rate after the second-round testing (P>0.05). The proportion of anti-HBc+ donors was quite high in both HBV infection-confirmed (98.1%) and unconfirmed group (82.6%), and donors with seronegative and anti-HBs-only occupied a high proportion in the latter (P<0.05). Conclusion: Numerous repeated testing of NDR samples using NAT platforms cannot achieve complete confirmation of HBV infection. Supplementary anti-HBc testing can minimize potential OBI risk among NDR donors, and is low-cost and efficient.

Objective: To investigate the impact of current laboratory testing models and screening strategies on blood safety by analyzing repeat nucleic acid testing (NAT) results obtained from blood donors who had dual-reactive enzyme-linked immunosorbent assay (ELISA) results but were initially nonreactive by NAT. Methods: Samples from blood donors with dual-reactive ELISA results and initially nonreactive NAT results collected at Dalian Blood Center from 2017 to 2025 were included. Repeated testing was performed using two NAT systems: transcription-mediated amplification (TMA) and polymerase chain reaction (PCR). The results were analyzed in terms of the frequency of reactive NAT results and the testing strategies, including minipool and individual donation testing. Results: A total of 199 samples with dual-reactive ELISA results and initially nonreactive NAT results were included，comprising 66 HBsAg-reactive samples，130 anti-HCV-reactive samples，and 3 HIV Ag/Ab-reactive samples. Among the HBsAg-reactive samples，57（57/66，86.4%）showed at least one reactive NAT result upon repeated testing，and 49 showed two or more repeat reactive results. Anti-HBc was reactive in 64 samples（64/66，97.0%）and nonreactive in 2 samples（2/66，3.0%）；both anti-HBc-nonreactive samples remained nonreactive in repeated NAT. No stable repeat nucleic acid reactivity was observed in anti-HCV- or HIV Ag/Abreactive samples. The TMA system detected 50 reactive samples（50/66，75.8%）through three combined assays plus one discriminatory assay, whereas the PCR system detected 51 reactive samples (51/66, 77.3%) through four rounds of individual-donation testing. Fortyfour samples were reactive on both systems, 6 were reactive only on the TMA system, and 7 were reactive only on the PCR system. Conclusion: Among blood donors with dual-reactive ELISA results and initially non-reactive NAT results, HBsAg-reactive samples contain a high proportion of low viral load HBV-related cases, with intermittent and probabilistic nucleic acid detectability. Both testing frequency and detection strategy significantly affect the detection of low viral load samples. These findings highlight the importance of recognizing the detection characteristics of low viral load HBV-related samples in order to optimize blood screening strategies and improve blood safety.

Objective: To establish quality standards for pooled cryoprecipitate based on measured data, addressing the issues of wide variability in coagulation factor content attributable to individual donor differences and imprecise clinical dosing with single-bag cryoprecipitate. Methods: A total of 120 bags of fresh frozen plasma of different ABO blood groups were enrolled. Single-bag cryoprecipitate was prepared using either the centrifugation method or the siphonage method. For each blood group and each preparation method, every five single units of the same blood group were pooled into one bag of pooled cryoprecipitate. Factor Ⅷ content, fibrinogen content, and volume were measured in source plasma, single-bag cryoprecipitate, and pooled cryoprecipitate. Recovery rates and coefficients of variation were calculated, and the effect of the pooling process on product homogeneity was analyzed. Results: The factor Ⅷ content, fibrinogen content, and volume of pooled cryoprecipitate were significantly higher than those of single-unit cryoprecipitate and were linearly correlated with the number of units pooled. After pooling, the coefficient of variation for factor Ⅷ content decreased from 34.9%-35.2% (single units) to 18.2%-20.7% (pools), and the coefficient of variation for fibrinogen content decreased from 27.0%-28.6% to 13.1%-13.4%. The pooling procedure had no significant effect on the recovery rates of factor Ⅷ or fibrinogen (P>0.05). Conclusion: For pooled cryoprecipitate prepared by pooling five single units, the proposed quality standards are: factor Ⅷ content≥400 IU/bag, fibrinogen content≥750 mg/bag, volume 200-250 mL/bag, and sterility test negative. These standards can provide a basis for large-scale preparation and clinical application of pooled cryoprecipitate.

Objective To explore the effect of hydrogen molecules on the psychological state of submariners after long voyage.Methods A total of 197 submariners who had participated in a long-voyage mission were selected as the research objects by cluster sampling.They were randomly assigned to observation group or control group.The observation group was given hydrogen inhalation and hydrogen-enriched drinking water for 30 days,while the control group was given air inhalation and purified water.Before and after the intervention,mental health status was assessed by the Symptom Checklist 90(SCL-90),Self-rating Anxiety Scale(SAS),and Self-rating Depression Scale(SDS).The cognitive ability,such as digit conversion,visual memory,tracking goal,and number span were tested.Results After the intervention,the score of each dimension and positive items of SCL-90,as well as the total scores of SAS and SDS were decreased in both groups(P<0.05 or P<0.01),and the scores of depression and anxiety and positive items of SCL-90,as well as the total scores of SAS and SDS in the observation group were lower than those in the control group(P<0.01).The single correct response time for digit conversion in the observation group was shorter than that in the control group(P<0.01).Conclusion Hydrogen molecule can improve mental health and cognitive performance of submariners after long voyage.

Objective To investigate the correlation of plasma homocysteine(Hcy)level and the polymorphisms of its key metabolic enzymes methylenetetrahy-drofolate reductase(MTHFR)gene with ischemic stroke(IS).Methods A total of 310 patients with IS were enrolled as the case group and 330 healthy subjects during the same period were selected as the control group.Plasma Hcy concentration was detected by enzyme cycling method,and the real-time fluorescent quantitative PCR(RT-qPCR)was used to detecte the genotypes of MTHFR C677T.Results The frequencies of TT genotype(36.13%),CT genotype(10.00%)and T allele(28.06%)of MTHFR gene C677T locus in stroke patients were significantly higher than that in control group(P＜0.05).The frequency of the TT genotype was significantly higher in IS group compared to control group,indicating a recessive mode of inheritance(P＜0.05);In the dominant mode of inheritance,the frequency of CT+TT genotype in IS group was also significantly higher than that in control group(P＜0.05);The plasma Hay concentration of MTHFR C677T genotype TT,CT and CC patients was statistically different(P＜0.05),which were(20.91±6.78)μmol/L(17.20±5.39)μmol/L,(14.35±4.32)μmol/L,respectively;The area under the ROC curve(AUC)of plas-ma total Hcy level was 0.610(95%CI:0.566～0.653,P＜0.001).It indicated that it might play an impor-tant role in predicting the risk of suffering from IS.Multivariate Logistic regression analysis showed that plasma Hcy level and MTHFR C677T gene polymorphism were important risk factors of IS.Conclusions Elevated plasma Hcy level is associated with IS,and the synergistic effect of elevated Hcy level and MTHFR C677T gene mutation may increase the risk of IS.

Objective To investigate the relationship between methylenetetra-hydrofolatereductase(MTHFR)gene polymorphism and serum homocysteine(Hcy)level and subtypes of ischemic stroke(IS).Methods The study was conducted according to the matched principle of case-control design,310 patients with IS and 330 healthy people during the same period were selected as the case group and the control group.Recycling enzyme method and the real-time fluorescent quantitative PCR(RT-qPCR)method were used to detect the level of serum Hcy and the genotypes of MTHFR C677T,respectively.Results There was a significantly difference in MTHFR C677T genotype and allele frequency between the case and control groups(P＜0.05).The correlation analysis with different subtypes indicated that the frequencies of CT genotype(38.02%),TT genotype(10.74%),and T allele(29.75%)were significantly different in the LAA group(OR=1.662,95%CI:1.058-2.608,P＜0.05;OR=2.373,95%CI:1.110-5.073,P＜0.05;OR=1.663,95%CI:1.190-2.323,P＜0.05);The frequencies of TT genotype(10.53%)and T allele(27.30%)in SAO group were also significantly different(OR=2.130,95%CI:1.046-4.336,P＜0.05;OR=1.474,95%CI:1.075-2.021,P＜0.05).Further analysis of serum Hcy level showed that LAA group(19.55±5.61)μmol/L and SAO group(16.37±5.20)μmol/L were significantly higher than the control group(14.46±4.61)μmol/L(P＜0.001);Among the patients of both subtypes the serum Hcy levels in those with CT genotypes and TT genotypes were significantly higher than those in patients of CC genotypes(P＜0.001).Conclusions The gene polymorphism of MTHFR C677T has a significant effect on Hcy level in pa-tients with LAA and SAO stroke.

BACKGROUND: Senescent human skin primary fibroblast (FB) models have been established for studying aging-related, proliferative, and inflammatory skin diseases. The aim of this study was to compare the transcriptome characteristics of human primary dermal FBs from children and the elderly with four senescence models. METHODS: Human skin primary FBs were obtained from healthy children (FB-C) and elderly donors (FB-E). Senescence models were generated by ultraviolet B irradiation (FB-UVB), D-galactose stimulation (FB-D-gal), atazanavir treatment (FB-ATV), and replication exhaustion induction (FB-P30). Flow cytometry, immunofluorescence staining, real-time quantitative polymerase chain reaction, co-culturing with immune cells, and bulk RNA sequencing were used for systematic comparisons of the models. RESULTS: In comparison with FB-C, FB-E showed elevated expression of senescence-related genes related to the skin barrier and extracellular matrix, proinflammatory factors, chemokines, oxidative stress, and complement factors. In comparison with FB-E, FB-UVB and FB-ATV showed higher levels of senescence and expression of the genes related to the senescence-associated secretory phenotype (SASP), and their shaped immune microenvironment highly facilitated the activation of downstream immune cells, including T cells, macrophages, and natural killer cells. FB-P30 was most similar to FB-E in terms of general transcriptome features, such as FB migration and proliferation, and aging-related characteristics. FB-D-gal showed the lowest expression levels of senescence-related genes. In comparisons with the single-cell RNA sequencing results, FB-E showed almost complete simulation of the transcriptional spectrum of FBs in elderly patients with atopic dermatitis, followed by FB-P30 and FB-UVB. FB-E and FB-P30 showed higher similarity with the FBs in keloids. CONCLUSIONS Each senescent FB model exhibited different characteristics. In addition to showing upregulated expression of natural senescence features, FB-UVB and FB-ATV showed high expression levels of senescence-related genes, including those involved in the SASP, and FB-P30 showed the greatest similarity with FB-E. However, D-galactose-stimulated FBs did not clearly present aging characteristics.
Humans ; Fibroblasts/drug effects* ; Cellular Senescence/physiology* ; Skin/metabolism* ; Child ; Transcriptome/genetics* ; Aged ; Ultraviolet Rays ; Cells, Cultured ; Galactose/pharmacology*