Objective: To systematically analyze the confirmatory positivity of different combinations of HBsAg screening results in blood testing, providing data to support the optimization of blood donor eligibility management. Methods: A retrospective analysis was conducted on blood screening data from 174 266 voluntary blood donor samples at the Chongqing Blood Center between October 2021 and September 2022. Samples with inconsistent results between the two HBsAg enzymelinked immunosorbent assays (ELISA) and individual donor nucleic acid testing (NAT) were confirmed using an electrochemiluminescence immunoassay (ECLIA) and a neutralization test. The detection efficacy of four different HBsAg ELISA reagents was compared using the HBsAg-confirmed positive samples. Results: A total of 767(0.44%) HBV-reactive (HB-sAg and/or HBV DNA reactive) samples were detected. Among them, 344 samples with discordant serological and NAT results were collected, of which 64(18.6%) were confirmed positive by neutralization test. Additionally, 5 samples that were neutralization-negative but double-reactive for HBsAg and HBV DNA were confirmed as positive according to FDA guidance, resulting in a total of 69(20.1%) confirmed HBsAg-positive samples. There were significant differences in the neutralization test confirmation rates among different screening result categories (P<0.05): The group with dual HBsAg reagent reactivity (double reactive) & NAT-negative had the highest confirmation rate (96.9%, 31/32); the group reactive to only reagent 2 (single reactive) had a rate of 25.7% (29/113); while the confirmation rates for samples reactive to only reagent 1 and samples with isolated HBV DNA positivity were extremely low [0(0/34) and 2.4%(4/165), respectively]. The four commercial reagents showed significant differences in their ability to detect confirmed positive samples that were initially single reactive (P<0.05). Conclusion: Given the performance variations among HBsAg screening reagents, thorough performance verification is essential before implementation. When NAT is negative, dual HBsAg reactivity in screening can serve as a basis for confirming infection and directly deferring blood donors. However, confirming infection in donors with single HBsAg reactivity is more challenging, necessitating supplementary tests to rule out infection risk.

Objective To explore the relationship between plantar fascia stiffness and windlass mechanism and their impact on the arch,and provide a biomechanical mechanism explanation for plantar fascia and arch-related diseases.Methods A foot-plate model with 30° flexion angle at the metatarsophalangeal joint was constructed.The musculoskeletal model combined with the three-dimensional finite element analysis method was used,and the dynamic data of the foot during walking at the speed of 5 km/h was obtained using dual fluoroscopic imaging system(DFIS).The finite element model was verified,and the influence of plantar fascia stiffness on the capstan mechanism and arch-related mechanical parameters was explored.Results The finite element simulation analysis results were highly consistent with the foot data obtained by DFIS,confirming the validity of the model.With the increase of plantar fascia stiffness,the windlass effect and the stiffness of the longitudinal arch of the foot both showed an increasing trend,but the flexion angle of the metatarsophalangeal joint decreased,the distal stress of the plantar fascia gradually decreased,and the proximal stress increased;when the plantar fascia stiffness was 25％-150％,the width of the transverse arch of the foot increased with the increase of plantar fascia stiffness,while the height of the transverse arch decreased with the increase of plantar fascia stiffness;when the plantar fascia stiffness was 150％-200％,the width of the transverse arch of the foot decreased,the height increased,and the stiffness also increased.Conclusions An increase in plantar fascia stiffness can enhance the windlass mechanism to some extent,but it also leads to a reduction in metatarsophalangeal joint flexion.The stiffness of the plantar fascia affects the metatarsophalangeal joint flexion,thereby impacting the windlass mechanism and the distal tensile force of the plantar fascia.Together with the ground reaction force at the distal end of the metatarsals,these factors collectively influence the stiffness of the transverse arch of the foot.

Objective Based on 25 indicators including immune factors, cell count classification, and smear results of the knee joint fluid, machine learning models were established to distinguish between osteoarthritis (OA) and rheumatoid arthritis (RA). Methods 100 OA and 40 RA patients scheduled for total knee arthroplasty were enrolled respectively. Each patient's knee joint fluid was collected preoperatively. Nucleated cells were counted and classified. The expression levels of immune factors, including tumor necrosis factor alpha (TNF-α), interleukin-1 beta (IL-1β), IL-6, IL-8, IL-15, matrix metalloproteinase 3 (MMP3), MMP9, MMP13, rheumatoid factor (RF), serum amyloid A (SAA), C-reactive protein (CRP), and others were measured. Smears and microscopic classification of all the immune factors were performed. Independent influencing factors for OA or RA were identified using univariate binary logistic regression, Lasso regression, and multivariate binary logistic regression. Based on the independent influencing factors, three machine learning models were constructed which are logistic regression, random forest, and support vector machine. Receiver operating characteristic curve (ROC), calibration curve and decision curve analysis (DCA) were used to evaluate and compare the models. Results A total of 5 indicators in the knee joint fluid were screened out to distinguish OA and RA, which were IL-1β(odds ratio(OR)=10.512, 95× confidence interval (95×CI) was 1.048-105.42, P=0.045), IL-6 (OR=1.007, 95×CI was 1.001-1.014, P=0.022), MMP9 (OR=3.202, 95×CI was 1.235-8.305, P=0.017), MMP13 (OR=1.002, 95× CI was 1-1.004, P=0.049), and RF (OR=1.091, 95×CI was 1.01-1.179, P=0.026). According to the results of ROC, calibration curve and DCA, the accuracy (0.979), sensitivity (0.98) and area under the curve (AUC, 0.996, 95×CI was 0.991-1) of the random forest model were the highest. It has good validity and feasibility, and its distinguishing ability is better than the other two models. Conclusion The machine learning model based on immune factors in the knee joint fluid holds significant value in distinguishing OA and RA. It provides an important reference for the clinical early differential diagnosis, prevention and treatment of OA and RA.
Humans ; Arthritis, Rheumatoid/metabolism* ; Machine Learning ; Male ; Female ; Middle Aged ; Aged ; Synovial Fluid/immunology* ; Osteoarthritis, Knee/metabolism* ; Knee Joint/metabolism* ; ROC Curve ; Diagnosis, Differential

Objective To explore the relationship between plantar fascia stiffness and windlass mechanism and their impact on the arch,and provide a biomechanical mechanism explanation for plantar fascia and arch-related diseases.Methods A foot-plate model with 30° flexion angle at the metatarsophalangeal joint was constructed.The musculoskeletal model combined with the three-dimensional finite element analysis method was used,and the dynamic data of the foot during walking at the speed of 5 km/h was obtained using dual fluoroscopic imaging system(DFIS).The finite element model was verified,and the influence of plantar fascia stiffness on the capstan mechanism and arch-related mechanical parameters was explored.Results The finite element simulation analysis results were highly consistent with the foot data obtained by DFIS,confirming the validity of the model.With the increase of plantar fascia stiffness,the windlass effect and the stiffness of the longitudinal arch of the foot both showed an increasing trend,but the flexion angle of the metatarsophalangeal joint decreased,the distal stress of the plantar fascia gradually decreased,and the proximal stress increased;when the plantar fascia stiffness was 25％-150％,the width of the transverse arch of the foot increased with the increase of plantar fascia stiffness,while the height of the transverse arch decreased with the increase of plantar fascia stiffness;when the plantar fascia stiffness was 150％-200％,the width of the transverse arch of the foot decreased,the height increased,and the stiffness also increased.Conclusions An increase in plantar fascia stiffness can enhance the windlass mechanism to some extent,but it also leads to a reduction in metatarsophalangeal joint flexion.The stiffness of the plantar fascia affects the metatarsophalangeal joint flexion,thereby impacting the windlass mechanism and the distal tensile force of the plantar fascia.Together with the ground reaction force at the distal end of the metatarsals,these factors collectively influence the stiffness of the transverse arch of the foot.

OBJECTIVE To investigate the efficacy and safety of hetrombopag combined with low-dose prednison in the treatment of patients with refractory/recurrent primary immune thrombocytopenia(ITP). METHODS A total of 40 patients with ITP who failed to respond to previous treatment or relapsed in the Department of Hematology of Gansu Provincial People’s Hospital From July 2021 to August 2022 were selected. Used randomized controlled trial research methods, according to the treatment plan, they were divided into observation group and control group, with 20 cases in each group. The control group was treated with low-dose prednison alone. The observation group was combined with hetrombopag treatment on this basis. The efficacy and adverse reactions were compared between the two groups. RESULTS Treatment 6 weeks, patients who's proportion of platelet counts(PLT) reached≥50×109·L−1 and ≥30×109·L−1 in observation group were higher than control group with statistically significant differences in both groups[90%(18/20) vs 50%(10/20), P＝0.006; 90%(18/20) vs 65%(13/20), P＝0.130]; The study also indicated a statistically significant difference in favour of observation group compared with control group in the odds of achieving the outcome of a PLT≥50×109·L−1at least once during 6-week treatment[90%(18/20) vs 55%(11/20), P＝0.147], was more than placebo-treated one. The median time of PLT ≥ 50×109·L−1 for the first time within 6 weeks of treatment in the observation group was 3 weeks, which was the same as that in the control group. After 6 weeks of treatment, the median platelet count in the observation group was higher than that in the control group[97.50(58.25−166.75)×109·L−1 vs 45.50(13.25−82.50)×109·L−1 , P<0.05]. The median PLT count in the observation group was higher than that in the control group at week 1−6 after treatment, and the curative effect was significant. The two groups of patients tolerated the regimen well, and the degree of adverse reactions was mild, which improved quickly after symptomatic treatment. CONCLUSION Hetrombopag combined with low-dose prednison has a high effective rate in the treatment of refractory/recurrent ITP, which is better than that of single use, and the adverse reactions are tolerable, so it can be widely used in clinical practice.

Objective To conduct Rh blood group serological testing and third-generation sequencing(TGS)on 22 RhD variant voluntary blood donors in Chongqing and explore the phenotypic distribution and genotyping of RhD variants in Chongqing.Methods From January to August 2023,individuals who participated in blood donation in our blood center were selected as the study objects.RhD variant phenotype identification was performed using routine serological methods.Once the RhD variants were identified,tests on different antigenic epitopes of RhD were conducted using a D-screen assay kit.Furthermore,after the genomic DNA from 22 RhD variant blood samples was extracted,imbraided primers design and multi-segment amplification and splicing were used to sequence the full-length RHD gene for TGS.The RHD gene sequence was analyzed using SnapGene software.Results Among the 22 RhD variants,8 were DVI type 3(36.36%),with the main mutation of RHD-CE(3-6)-D hybrid allele.Six cases(27.27%)showed partial weak D15 type,with the main mutation of c.845G>A.There were 6 cases of Asia type Del(27.27%),with the main mutation of c.1227G>A.One case was weak D17 type with a mutation of c.340C>T and 1 case speculated to be partial D(c.491A>T,p.Asp164Val,missense mutation).Conclusion The most common RhD variant phenotype among blood donors in Chongqing is DVI type 3,and the full-length haplotype sequence of RHD variant alleles can be obtained by Pacific Bioscience single-molecule real-time sequencing(SMRT).

Objective To demonstrate the feasibility of oblique lumbar interbody fusion(OLIF)com-bined with 4-screw fixation for treating two-level lumbar degenerative diseases.Methods An intact finite element model of L3-S1(MO)was constructed and validated.Then,we constructed the M1 model by simulating OLIF surgery at L3/4 and L4/5 segments on the MO model.By attachment of posterior 4-screw or 6-screw fixation to the M1 model,three 4-screw fixation models(M2-M4)and one 6-screw fixation model(M5)were established.The segmental and overall range of motion(ROM)and the peak von Mises stresses of superior endplate,cage,and posterior screw-rod were investigated under each implanted condition.Results Under the motion modes of forward flexion,backward extension,bilateral(left and right)flexion,and left and right rotation,the L3/4 ROM of M2 model and L4/5 ROM of M3 model increased,while the L3/4 and L4/5 ROM of M4 and M5 models significantly decreased compared with those of M1 model.Under all motion modes,the L4 superior endplate in M2 model and the L5 superior endplate in M3 model showed the maximum peak von Mises stress,and the peak von Mises stresses of L4 and L5 superior endplates in M4 and M5 models were close.The L3/4 cage in M2 model and the L4/5 cage in M3 model showcased the largest peak von Mises stress,and the peak von Mises stresses of cages in M4 and M5 models were close.The peak stresses of internal fixation in M2-M5 models were close.Conclusion Four-screw fixa-tion can replace 6-screw fixation in the OLIF surgery for treating two-level degenerative lumbar diseases.

Objective:To evaluate the real-world short-term effectiveness of ixekizumab in the treatment of psoriasis, and to investigate factors influencing the effectiveness.Methods:Baseline data and short-term effectiveness evaluation results were retrospectively collected from patients with psoriasis, who received ixekizumab treatment in Department of Dermatology, Xiangya Hospital from November 2019 to September 2021. A descriptive analysis was performed on the baseline characteristics of patients, continuous data were described as median (lower quartile, upper quartile), and categorical data were described as percentages. Comparisons of disease severity scores before and after the treatment with ixekizumab were performed using Wilcoxon signed-rank test or paired McNemar test. Multivariable logistic regression analysis was conducted to explore factors influencing the effectiveness of 4-week ixekizumab treatment.Results:A total of 118 patients with psoriasis were included, including 94 males and 24 females, and their age [ M ( Q1, Q3) ] was 43.4 (32.5, 53.0) years; plaque psoriasis (99 cases, 83.9%) and severe psoriasis (72 cases, 68.6%) predominated among the 118 patients, and skin lesions were mainly located on the scalp (59/116, 50.9%). Among the 49 patients who had received 2-week ixekizumab treatment, 27 (55.1%) achieved a 50% improvement in the psoriasis area and severity index (PASI) score (PASI50) ; after 4-week treatment, 44 (89.8%), 30 (61.2%), 13 (26.5%) and 10 (20.4%) patients achieved PASI50/75/90/100 respectively, and their PASI scores (2.1 [1.1, 7.1]), involved body surface area (3.9% [0.5%, 14.5%]), dermatology life quality index scores (1.0 [0.0, 2.0]) and physician global assessment (PGA) scores (1.0 [1.0, 3.0]) were significantly lower than the corresponding scores at baseline (12.4 [8.8, 23.2], 22.0% [11.3%, 43.4%], 6.0 [3.0, 11.0], 4.0 [3.0, 5.0], respectively; all P < 0.001]. Multivariable logistic regression analysis showed that the baseline body mass index was significantly associated with the PASI75 response rate ( OR = 0.814, 95% CI: 0.659 - 0.958, P = 0.029) and the proportion of patients with PGA0/1 ( OR = 0.743, 95% CI: 0.562 - 0.917, P = 0.017) after 4-week ixekizumab treatment, and the baseline BSA score was significantly associated with the proportion of patients with PGA0/1 after 4-week ixekizumab treatment ( OR = 0.924, 95% CI: 0.870 - 0.968, P = 0.003) . Conclusion:The 4-week ixekizumab treatment significantly decreased the severity of psoriasis, and may be more effective in patients with lower disease severity and lower body mass index at baseline.

Objective: To explore the effect of valproic acid with different loading doses in treatment of children with status epilepticus. Methods: The data of children who were hospitalized in the intensive care unit of the Children′s Hospital Affiliated to Zhejiang University because of status epilepticus from January 1, 2013 to December 31, 2017 were collected.All the patients were divided into different groups according to loading dose of valproic acid.The effect were analyzed in different groups. Results: (1)There were 66 children with status epilepticus were admitted, including 35 males and 31 females.Among all children with status epilepticus, the etiology included epilepsy(n=36, 54.5%), intracranial infection(n=16, 24.2%), hypoxic asphyxia (n=3, 4.5%), intracranial tumor(n=2, 3.0%), abnormal brain development(n=2, 3.0%), intracranial hemorrhage(n=2, 3.0%), and etiology was not clear(n=5, 7.6%). (2)All children with status epilepticus were divided into four groups according to different valproic acid loading dose(0 mg/kg, 10-15 mg/kg, 16-39 mg/kg, 40 mg/kg). There are no significant differences in gender and age among groups.There were no significant differences in duration of status epilepticus and epileptic treatment efficiency(P=0.402, 0.034). (3)All children were monitored for liver function after the treatment of sodium valproate, and no patient had been found increased alanine aminotransferase. Conclusion There are no significant differences in the effect of different valproic acid loading doses in children with status epilepticus, and no adverse side effects are observed in children with status epilepticus who received a dose of 40 mg/kg.

Objective To prepare and characterize specific monoclonal antibodies( McAbs) against the heavy chain of botulinum neurotoxin serotype A ( BoNT/AHc ) .Methods BALB/c mice were immunized with purified BoNT/AHc protein.After the fusion of mouse splenic cells with SP2/0 cells, hybridoma cell lines secreted McAbs against BoNT/AHc. The McAbs obtained were characterized by indirect ELISA, Western blotting and rapid isotypingassay before being used in ELISA to detect interaction sites in McAbs and BoNT/AHc preliminarily.Results Antigen protein BoNT/AHc of high purification was obtained.Four hybridoma cell lines secreting McAbs against BoNT/AHc were screened,named 1A4,3H3, 3H7 and 5H8,respectively.Their titers of McAbs were all above 3.0 ×103 .They were specifically combined with BoNT/AHc protein by Western blotting.The isotype of 1A4 and 3H7 was IgG1(Κ),that of 3H3 was IgM(Κ),and that of 5H8 was IgG2b(Κ).Additive ELISA showed that epitopes recognized by the four McAbs were close.ELISA analysis confirmed the interaction epitopes in McAbs and BoNT/AHc.Conclusion Monoclonal antibodies against BoNT/AHc are prepared and characterized,providing effective tools for studying the neutralizing antibody and antibody epitopes of BoNT/AHc.