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.

Purpose: This Phase II trial was objected to evaluate the efficacy and safety of adding fulvestrant to neoadjuvant chemotherapy in patients with estrogen receptor (ER)+/human epidermal growth factor receptor 2 (HER2)– locally advanced breast cancer (LABC). Additionally, the study aimed to investigate the association of 16α-18F-fluoro-17β-fluoroestradiol (18F-FES) positron emission tomography (PET)–computed tomography (CT) and metabolites with efficacy. Materials and Methods: Fulvestrant and EC-T regimen were given to ER+/HER2– LABC patients before surgery. At baseline, patients received 18F-FES PET-CT scan, and plasma samples were taken for liquid chromatography–mass spectrometry analysis. The primary endpoint was objective response rate (ORR). Secondary endpoints included total pathologic complete response (tpCR) and safety. Results: Among the 36 patients enrolled, the ORR was 86.1%, the tpCR rate was 8.3%. The incidence of grade ≥ 3 treatment-emergent adverse events was 22%. The decrease in ER value in sensitive patients was larger than that in non-sensitive patients, as was Ki-67 (p < 0.05). The maximum standardized uptake value, mean standardized uptake values, total lesion ER expression of 18F-FES PET-CT in sensitive patients were significantly higher than those in non-sensitive patients (p < 0.05). Moreover, these parameters were significantly correlated with Miller and Payne grade and the change in ER expression before and after treatment (p < 0.05). Thirteen differential expressed metabolites were identified, which were markedly enriched in 19 metabolic pathways. Conclusion This regimen demonstrated acceptable toxicity and encouraging antitumor efficacy. 18F-FES PET-CT might serve as a tool to predict the effectiveness of this therapy. Altered metabolites or metabolic pathways might be associated with treatment response.

Purpose: This Phase II trial was objected to evaluate the efficacy and safety of adding fulvestrant to neoadjuvant chemotherapy in patients with estrogen receptor (ER)+/human epidermal growth factor receptor 2 (HER2)– locally advanced breast cancer (LABC). Additionally, the study aimed to investigate the association of 16α-18F-fluoro-17β-fluoroestradiol (18F-FES) positron emission tomography (PET)–computed tomography (CT) and metabolites with efficacy. Materials and Methods: Fulvestrant and EC-T regimen were given to ER+/HER2– LABC patients before surgery. At baseline, patients received 18F-FES PET-CT scan, and plasma samples were taken for liquid chromatography–mass spectrometry analysis. The primary endpoint was objective response rate (ORR). Secondary endpoints included total pathologic complete response (tpCR) and safety. Results: Among the 36 patients enrolled, the ORR was 86.1%, the tpCR rate was 8.3%. The incidence of grade ≥ 3 treatment-emergent adverse events was 22%. The decrease in ER value in sensitive patients was larger than that in non-sensitive patients, as was Ki-67 (p < 0.05). The maximum standardized uptake value, mean standardized uptake values, total lesion ER expression of 18F-FES PET-CT in sensitive patients were significantly higher than those in non-sensitive patients (p < 0.05). Moreover, these parameters were significantly correlated with Miller and Payne grade and the change in ER expression before and after treatment (p < 0.05). Thirteen differential expressed metabolites were identified, which were markedly enriched in 19 metabolic pathways. Conclusion This regimen demonstrated acceptable toxicity and encouraging antitumor efficacy. 18F-FES PET-CT might serve as a tool to predict the effectiveness of this therapy. Altered metabolites or metabolic pathways might be associated with treatment response.

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 evaluate the disease risk of Vibrio parahaemolyticus (VP) in aquatic products of raw food in Guangzhou. Methods VP detection was carried out in aquatic products of raw food sold in Guangzhou from 2009 to 2022. Gene sequence and wgSNP analysis of 30 VP strains (including 15 food strains and 15 patient strains) were performed for the detection rate of pathogenic VP. sQMRA was applied to assess VP risk of aquatic products of raw food. Results The detection rate of VP in raw aquatic products in Guangzhou was 7.30% (98/1 343). The detection rate of TDH virulence gene in patient strains was 86.70% (13/15) , and the detection rate of TRH was 6.67% (1/15). In 15 food strains, TDH and TRH were negative. The WgSNP analysis showed that 2 food strains had high similarity with the patient strains, indicating the same cluster. Risk assessment showed that the number of Vibrio parahaemolyticus infection cases caused by intaking aquatic products of raw food in Guangzhou was 384 ever year. Conclusion The detection rate of VP in aquatic products of raw food is high in Guangzhou , and the detection rate of VP virulence genes in aquatic products of raw food is low. Gene sequence and wgSNP analysis can be used for risk assessment of food pathogenic bacteria. The risk of disease of Vibrio parahaemolyticus in aquatic products of raw food is high.

Objective: To understand the current status of tuberculosis prevention and control knowledge and perceived stress among college and middle school students with pulmonary tuberculosis (PTB) in Yantai City, and to analyze the related factors, so as to provide a basis for the school to carry out health education and psychological counseling. Methods: A matched case control study was conducted, with 100 PTB student patients in junior high school and above who were diagnosed at designated medical institutions from October 2020 to October 2024. Four healthy control students of the same gender, same dormitory, or same class were selected for each case. Therefore, 100 cases and 400 controls were investigated by questionnaire. The following information was collected: personal basic information; tuberculosis prevention and control awareness; and scores of the Chinese Perceived Stress Scale (CPSS). Conditional Logistic regression model and mixed linear models were used to compare the PTB prevention and control awareness rate, as well as the perceived stress between the case and control groups. Multiple linear regression analysis was used to analyze the factors that may affect the perceived stress of students with PTB. Results: The awareness rates of four tuberculosis knowledge items (symptoms of PTB, main causes of onset after infection, consequences of PTB patients not receiving standardized and complete treatment, the most important method to prevent PTB) were higher in the case group (40.00%, 72.00% , 38.00%, 49.00%) than the control group (21.50%, 57.50%, 22.25%, 31.25%) and the differences were statistically significant ( Wald χ 2=18.44, 8.78, 13.20, 16.89, all P <0.01). The tension score (10.49±4.20), loss of control score ( 11.21± 4.58), and total score (21.70±6.88) in the case group were higher than the control group (9.35±4.73, 9.75±5.60, 19.09±8.36) and the differences were statistically significant ( t =2.21, 2.42, 2.88, all P <0.05). The results of multiple linear regression analysis showed that age ≥ 18 years and family history of tuberculosis were the related factors affecting the overall perceived stress and tension of college and middle school students with PTB ( B total scores =4.50, 5.91; B tension score =2.39, 3.23, all P <0.05). Conclusions The tuberculosis prevention and control awareness rate, and the perceived stress of college and middle school students with PTB in Yantai are both higher than students without tuberculosis. Moreover, the perceived stress of students with PTB who are aged ≥18 years or have a family history of tuberculosis is even higher.

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.