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 characterize the sequence polymorphism of HLA-A, -B, and -C loci in the northern Han Chinese population and to evaluate their selection signals and phylogenetic patterns based on long-read sequencing data. Methods: A total of 408 unrelated healthy blood donors were enrolled. Long-read sequencing of HLA-A, -B, and -C loci was performed using the PacBio Sequel II platform. The Ewens-Watterson neutrality test, sliding-window nucleotide diversity (π) and Tajima′s D analyses were conducted, together with genetic distance heatmaps, principal coordinates analysis (PCoA), and maximum likelihood phylogenetic analysis to assess polymorphism distribution, selection signals, and phylogenetic structure across the three loci. Results: The analyzed sequence lengths for the HLA-A, -B, and -C loci were 3 257 bp, 3 794 bp, and 3 831 bp, respectively; the numbers of locus-specific sequence types were 44, 82, and 56, with corresponding locus-specific sequence type diversities of 0.905 2, 0.964 9, and 0.939 8, respectively. The Ewens-Watterson test showed no significant deviation from neutrality (P>0.05). Sliding-window analysis revealed elevated π and Tajima′s D values in exons 2 and 3 as well as in certain intronic regions of HLA-A and HLA-B, whereas HLA-C exhibited relatively lower overall diversity. Genetic distance heatmaps, PCoA, and phylogenetic analysis consistently showed clear clustering in HLA-A and HLA-C, while HLA-B displayed the highest phylogenetic heterogeneity. Conclusion: HLA-A, -B, and -C gene sequences in the northern Chinese Han population exhibit high levels of polymorphism and marked regional heterogeneity. HLA-B shows greater diversity, stronger signals of selection, and more complex phylogenetic structure compared with HLA-A and HLA-C.

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 analyze the epidemiological characteristics, associated factors, and vaccine effectiveness of two pertussis cluster outbreaks in two primary schools in Yangzhong City in 2025, so as to provide evidence for school based epidemic prevention and control. Methods: From August 26 to 30, 2025, a pertussis questionnaire was administered to the epidemic affected classes of two primary schools (school A and school B) in Yangzhong City. A descriptive epidemiological retrospective analysis was used to characterize the pertussis cluster outbreaks in Yangzhong City from March to July 2025. A 1∶5 matched case control study (79 cases, 395 controls) was performed. Multivariate Logistic regression was used to identify associated factors, and the clinical symptom incidence rates, types of pertussis containing vaccines, and timeliness of vaccination were compared between groups using Fisher s exact test. Results: From March to July 2025, a total of 79 pertussis cases were reported in the two schools, with attack rates of 1.33% and 1.01%, respectively. Cases were predominantly aged 7-8 years (85.37% in school A, 73.68% in school B), and the main clinical manifestation was productive cough (63.29%). The pneumonia incidence rate among hospitalized cases ( 57.14 %) was higher than that among nonhospitalized cases(4.17%)(Fisher s exact test, P <0.01). The interval from the last dose to onset was concentrated at 6 to <7 years (44 cases). Logistic regression showed that children exposed to secondhand smoke in daily life ( OR = 3.86 ), those whose desk mates or front/back desk mates took leave due to cough ( OR =4.67), and those whose dining table mates or front/back table mates took leave due to cough ( OR =3.67) had significantly higher risks of pertussis (all P <0.05). A high proportion of both the case group and the control group received the acellular DTaP vaccine (97.47% and 96.96%, respectively),while a low proportion received the pentavalent vaccine (1.27% and 3.04%, respectively). Additionally, one case received only three doses of the acellular DTaP vaccine.The difference in vaccine type distribution between the two groups was not statistically significant (Fisher s exact test, P =0.31). Conclusions The outbreaks represent breakthrough infections under high vaccine coverage. Close contact and secondhand smoke exposure are the main risk factors. A booster immunization strategy with diphtheria-tetanus-pertussis vaccine should be implemented for school aged children.

Objective: To establish a method for determining the molecular weight and molecular weight distribution of Poly(Lactide-co-Glycolide Acid) (PLGA) using Size Exclusion Chromatography-Refractive Index-Multiangle Laser Light Scattering (SEC-RI-MALLS) and Size Exclusion Chromatography-Refractive Index (SEC-RID), and to compare the results obtained from these two methods.
Methods: For SEC-RI-MALLS, tetrahydrofuran was used as the mobile phase, Shodex GPC KF-803L was employed as the chromatographic column with a flow rate of 1 mL·min^-1, column temperature at 30 ℃, and an injection volume of 100 μL. For SEC-RID, tetrahydrofuran was also used as the mobile phase, Agilent PLgel 5 μm MIXD-D was used as the chromatographic column with a flow rate of 1 mL·min^-1, column temperature at 30 ℃, differential detector temperature at 35 ℃, and an injection volume of 20 μL. The molecular weight and molecular weight distribution were calculated using Agilent’s GPC software. The newly established methods were validated methodologically, and the molecular weight and molecular weight distribution of 13 batches of samples were determined.
Results: The precision, accuracy, stability, and repeatability tests for SEC-RI-MALLS showed RSD values of 1.35%, 1.58%, 1.53%, and 1.26%, respectively. The SEC-RID method exhibited good linearity (r=0.999 9), with RSD values for precision, accuracy, stability, and repeatability tests (n=6) of 2.05%, 1.62%, 1.30%, and 2.97%, respectively. The results obtained from SEC-RI-MALLS were lower than those from SEC-RID, and the molecular weight distribution coefficient was smaller, but the results from the paired T-test performed with the value measured by SEC-RID method and the value measured by SEC-RI-MALLS method multiplied a conversion coefficient of 1.5 showed no significant difference between the two methods.
Conclusion: Both methods are stable and reliable, and can be used for the determination of PLGA molecular weight and molecular weight distribution based on the specific situations.

Objective To longitudinally analyze the changes in perioperative nutritional indicators in elderly patients with spontaneous intracerebral hemorrhage(ICH)and their correlation with the score of modified Rankin scale(mRS)score.Methods A total of 295 elderly ICH patients ad-mitted to the neurosurgery intensive care unit of North China University of Science and Technolo-gy Affiliated Hospital from June 2022 to November 2024 were consecutively enrolled in this study.The levels of relevant nutritional indicators were measured before(T1),and in 1(T2),3(T3),5(T4)and 7 d(T5)after surgery.According to the mRS score in 90 d after onset of the disease,they were divided into a good prognosis group(mRS score≤ 2,114 cases)and a poor prognosis group(mRS score≥3,181 cases).The general data and levels of nutritional indicators at above time points were compared between the two groups.Binary logistic regression analysis was applied to study the relationship between the perioperative nutritional indicator levels and the prognosis in elderly patients with spontaneous ICH.Results The poor prognosis group had significantly higher SBP,larger proportions of stroke history,hemorrhage in the brainstem and midline dis-placement,and increased NIHSS score than the good prognosis group(P＜0.05,P＜0.01).Obvi-ously lower BMI(56.48±9.54 kg vs 66.62±8.12 kg),decreased serum levels of albumin[40.24(39.10,41.16)g/L vs 43.30(40.65,45.50)g/L],prealbumin[203.00(164.00,261.00)mg/L vs 229.00(180.00,282.00)mg/L]and TC[4.68(4.11,5.39)mmol/L vs 4.91(4.47,5.66)mmol/L],reduced lymphocyte count[1.58(0.95,2.03)× 109/L vs 1.77(1.99,1.91)× 109/L],and reduced GCS[7.00(5.00,10.00)vs 9.00(7.00,13.00)]and Barthel[55.00(43.00,64.00)vs 61.00(52.00,69.00)]scores at admission were observed in the poor prognosis group than the good prognosis group(all P＜0.01).At all different time points,the poor prognosis group also got notably higher Controlling Nutritional Status(CONUT)scores(reaching the highest levels at 3 d after opera-tion),and lower Prognostic Nutritional Index(PNI)score and Geriatric Nutritional Risk Index(GNRI)score(both declining the lowest levels at same time)when compared with the poor prog-nosis group(all P＜0.01).Binary logistic regression analysis showed that COUNT scores,PNI scores and GNRI scores before(T1)and at 1(T2),3(T3),5(T4)and 7 d(T5)after operation were independent risk factors for 90-day poor prognosis in elderly patients with spontaneous ICH.Conclusion The fluctuations of 3 nutritional indicators at different time points in the periopera-tive period are closely associated with the 90-day prognosis of elderly ICH patients.Monitoring the changes in the nutritional indicators can quickly and conveniently predict the prognosis of the pa-tients,which has high clinical application value.

Objective To predict the value of admission dehydration state combined with fluid accumulation index for post-operative prognosis in elderly patients with intracerebral hemorrhage(ICH).Methods A retrospective study was conducted on 320 elderly ICH patients receiving surgical treatment in Department of Neurosurgery and then admitted to its Intensive Care Unit of the Affiliated Hospital of North China University of Science and Technology from May 2023 to March 2024.According to the survival status at 30 d after onset,they were divided into a survival group(202 cases)and a death group(118 cases).Clinical data such as basic information,admission vital signs,laboratory indicators,and fluid supplementation were compared between the two groups.ROC curve was plotted.Results The death group exhibited significantly advanced age,more bleeding sites,higher 7-day fluid accumulation index,and larger proportions of ventricular rupture,midline displacement and admission dehydration status,but lower uric acid level than the the survival group(P＜0.05,P＜0.01).Binary logistic regression analysis showed that admission dehydration status and 7-day fluid accumulation index were risk factors for 30-day mortality in elderly ICH patients after surgery(P＜0.01).ROC curve analysis showed that the AUC value of admission dehydration status combined with 7-day fluid accumulation index in predicting 30-day death of elderly ICH patients after surgery was 0.774(95％CI:0.722-0.825),and that of the combination was better than that of each indicator alone(P＜0.05).Conclusion Hospital dehydration status combined with 7-day fluid accumulation index has the best effectiveness in predicting 30-day mortality in elderly ICH patients after surgical treatment.

Objective:To explore the genetic characteristics of a Chinese pedigree with rare mosaic 11q partial duplication and its pathogenetic mechanisms.Methods:A pedigree which underwent prenatal diagnosis at Wenzhou Central Hospital between September 25, 2015 and November 30, 2023 was selected for the study. Clinical data were collected from the pedigree. Peripheral blood samples from the parents, amniotic fluid from the fetus, and peripheral blood sample from the neonate were obtained. Genetic testing was carried out by using G-banded chromosomal karyotyping and single nucleotide polymorphism array (SNP-array) technology. Relevant literature was searched in the CNKI, Wanfang Data Knowledge Service Platform, and PubMed databases to summarize the clinical phenotypes of patients with 11q partial duplication. This study was approved by the Medical Ethics Committee of Wenzhou Central Hospital (Ethics No. L2024-07-080).Results:The pregnant woman (G 3) had a history of adverse pregnancy outcomes. During her first pregnancy (G 1), prenatal ultrasound indicated intrauterine growth restriction and a Dandy-Walker variant. Follow-up at 8 years of age showed developmental delays and mild intellectual disability. During her second pregnancy (G 2), prenatal ultrasound revealed nasal bone hypoplasia, and the pregnancy was terminated at 23rd gestational week. During her third pregnancy (G 3), all prenatal tests were normal, and the neonate showed normal growth and development at 4 months of age. The karyotype of amniotic fluid of her first pregnancy was 46, X? , and the SNP-array analysis of neonatal peripheral blood showed arr[GRCh37/hg19]11q13.4q25(70432450_134607121)×2~3, with a mosaicism rate being approximately 40%. The karyotype for her second pregnancy was 46, X? , rec(11)dup(11q)inv(11)(p15q13)dmat[6]/46, X? [27], and the SNP-array result was arr[GRCh38]11q13.4q25(71406636_135067522)×2~3, with a mosaicism rate being approximately 75%. The karyotype for her third pregnancy was 46, X? , inv(11)(p15q13)mat, and the SNP-array result was arr(XN)×1, (1~22)×2. The karyotype of the woman was 46, XX, inv(11)(p15q13), and that of her husband was 46, XY. A review of 12 similar cases (including G 1) from the literature revealed that the common clinical phenotypes of 11q partial duplication included intellectual disability (12/12), developmental delay (12/12), ear abnormalities (12/12), microcephaly (10/12), seizures (8/12), hypotonia (8/12), and congenital heart malformations (7/12). Conclusion:Mosaic partial duplication of 11q may underlie the genetic etiology of this pedigree. The pregnant woman is a carrier of an inversion on chromosome 11, which might have formed the mosaic 11q partial duplication through meiotic errors and mitotic trisomy rescue mechanisms during reproduction.

Objective:To evaluate the protective effectiveness (VE) of the acellular pertussis vaccine (aPV) against pertussis in children aged 2 months to 6 years.Methods:A test-negative case-control study was conducted among children aged 2 months to 6 years who sought medical care for cough and underwent pertussis nucleic acid testing at sentinel surveillance hospitals in Zhejiang Province in 2024. Cases were defined as those with positive pertussis nucleic acid test results, while controls were test-negative individuals matched 1∶1 based on propensity scores using the caliper matching method. Conditional logistic regression models were used to calculate odds ratios ( ORs) and VEs. Results:Among the 658 participants, 31.76% (209 cases) tested positive for pertussis. After propensity score matching, 203 cases and 203 controls were included in the analysis. The VE of 1-2, 3, and 4 doses of aPV against pertussis was 52.46% (95% CI:-39.82%-83.84%), 65.22% (95% CI: 6.86%-87.02%), and 72.21% (95% CI: 34.33%-88.24%), respectively. For pertussis-related hospitalization, the VE of 1-3 and 4 doses was 80.95% (95% CI:31.38%-94.71%) and 86.79% (95% CI: 51.89%-96.37%). The VE for those who completed 4 doses of vaccination and had intervals of less than 2 years, 2 years, 3 years, and 4 years or more after vaccination were 91.15% (95% CI: 67.61%-97.58%), 84.70% (95% CI: 43.71%-95.84%),56.23% (95% CI:-47.58%-87.02%), and 49.92% (95% CI:-83.74%-86.35%), respectively. Conclusion:The VE of aPV against pertussis in children aged 2 months to 6 years increases with the number of doses administered, and it is more effective in preventing hospitalization due to pertussis. The VE declines rapidly over time after the last dose. It is recommended to follow the new pertussis immunization program for timely and full vaccination.

Objective To investigate the effect of obstructive sleep apnea(OSA)on behavioral problems in children and the association between them.Methods A simple random sampling method was used to select 100 children aged 4 to 12 years for the case group.All of them were diagnosed with OSA through overnight polysomnography at the Sleep Medicine Center,West China Fourth Hospital,Sichuan University between October 2022 and October 2023.An additional 100 children without snoring symptoms and clinically evaluated and confirmed as not having OSA were enrolled as the control group.General demographic data of the participants were collected.The Caregiver Report Form of the Achenbach Child Behavior Checklist(CBCL)was used for behavioral problem assessment,and polysomnography data were collected.The chi-square/t test was used to analyze the inter-group differences in general data,the total score of behavioral problems,and scores for each dimension.Linear regression was performed to analyze the relationship between OSA and the total score for children's behavioral problems and those for the different dimensions.Logistic regression was applied to analyze the relationship between the obstructive apnoea-hypopnea index(OAHI)and behavioral problems in children with OSA.A logistic regression model integrating the OAHI×sex interaction term was constructed to evaluate the moderating effect of sex on the association between OAHI and behavioral problems.Results No significant differences were observed in general demographic data between the case and control groups.The total score for behavioral problems and those for each dimension were higher in the case group than those in the control group,with the total score of the case group being 24.60±1.55 and that of the control group being 8.85±0.75(P<0.001).The results of the linear regression analysis showed a positive association between OSA and both the total score for behavioral problems(b=16.01;95%CI,12.56-19.47)and those for each dimension.The results of the logistic regression analysis showed that,after adjusting for covariates,OAHI was a risk factor for behavioral problems in children with OSA(odds ratio[OR]=1.17;95%CI,1.04-1.31).After stratification by sex and adjustment for covariates,the OR value of the effect of OAHI on behavioral problems was slightly higher in female participants(1.57)than that in male participants(1.21).The interaction effect analysis showed that sex moderated the association between OAHI and behavioral problems(OR=1.64;95%CI,1.02-2.64;P=0.04).Conclusion Children with OSA are prone to developing behavioral problems.OAHI is a risk factor for behavioral problems in children with OSA,with a potentially greater effect observed in girls.