ObjectiveThis study leverages structural data from antigen-antibody complexes of the influenza A virus neuraminidase (NA) protein to investigate the spatial recognition relationship between the antigenic epitopes and antibody paratopes. MethodsStructural data on NA protein antigen-antibody complexes were comprehensively collected from the SAbDab database, and processed to obtain the amino acid sequences and spatial distribution information on antigenic epitopes and corresponding antibody paratopes. Statistical analysis was conducted on the antibody sequences, frequency of use of genes, amino acid preferences, and the lengths of complementarity determining regions (CDR). Epitope hotspots for antibody binding were analyzed, and the spatial structural similarity of antibody paratopes was calculated and subjected to clustering, which allowed for a comprehensively exploration of the spatial recognition relationship between antigenic epitopes and antibodies. The specificity of antibodies targeting different antigenic epitope clusters was further validated through bio-layer interferometry (BLI) experiments. ResultsThe collected data revealed that the antigen-antibody complex structure data of influenza A virus NA protein in SAbDab database were mainly from H3N2, H7N9 and H1N1 subtypes. The hotspot regions of antigen epitopes were primarily located around the catalytic active site. The antibodies used for structural analysis were primarily derived from human and murine sources. Among murine antibodies, the most frequently used V-J gene combination was IGHV1-12*01/IGHJ2*01, while for human antibodies, the most common combination was IGHV1-69*01/IGHJ6*01. There were significant differences in the lengths and usage preferences of heavy chain CDR amino acids between antibodies that bind within the catalytic active site and those that bind to regions outside the catalytic active site. The results revealed that structurally similar antibodies could recognize the same epitopes, indicating a specific spatial recognition between antibody and antigen epitopes. Structural overlap in the binding regions was observed for antibodies with similar paratope structures, and the competitive binding of these antibodies to the epitope was confirmed through BLI experiments. ConclusionThe antigen epitopes of NA protein mainly ditributed around the catalytic active site and its surrounding loops. Spatial complementarity and electrostatic interactions play crucial roles in the recognition and binding of antibodies to antigenic epitopes in the catalytic region. There existed a spatial recognition relationship between antigens and antibodies that was independent of the uniqueness of antibody sequences, which means that antibodies with different sequences could potentially form similar local spatial structures and recognize the same epitopes.

ObjectiveTo analyze the impact of maternal postpartum depression (PPD) at 2 months postpartum on caregiving for infants aged2 to 24 months, and to provide a scientific basis for future maternal and infant healthcare services. MethodsBased on the Shanghai Maternal-Child Pairs Cohort, 1 060 mother-child pairs were selected from those fully participating in follow-up visits at 2, 6, 12, and 24 months postpartum. Pregnancy and childbirth-related information was collected using standardized questionnaire surveys and hospital obstetric and maternity records. The Edinburgh postpartum depression scale was used to assess the maternal postpartum depressive symptoms at 2 months postpartum. At 2, 6, 12, and 24 months postpartum, questionnaire survey was used to evaluate the maternal responsiveness in caregiving and the provision of early learning opportunities for infants. Scores for responsive caregiving and early learning opportunities at 2, 6, 12, and 24 months were grouped based on the 25th percentile (P₂₅) of total scores. The mixed-effects model was used to analyze the longitudinal impact of maternal postpartum depression at 2 months on the caregiving of 2 to 24-month-old infants. ResultsThe longitudinal results from the mixed-effects model did not show an impact of maternal PPD on infant responsive caregiving within 12 months and early learning opportunities within24 months. However, cross-sectional analysis revealed that, compared to the non-PPD group, the risk of low responsive caregiving at 2 months in the PPD group was 93% higher (OR=1.931, 95%CI: 1.113‒3.364, P=0.019). The risks for low provision of early learning opportunities at2 months and 24 months increased by 59% (OR=1.589, 95%CI: 1.082‒2.324, P=0.017) and 60% (OR=1.598, 95%CI:1.120‒2.279, P=0.010), respectively. ConclusionMaternal postpartum depression increases the risk of low responsive caregiving at 2 months, but its long-term effects warrant further research.

The Department of Thoracic Surgery of Shanghai Chest Hospital has performed esophageal function testing for over 30 years, being the only department of its kind in China with this capability. The pressure testing and 24-hour pH/impedance monitoring of the esophagus is of great help to assist in the diagnosis and treatment of benign and malignant esophageal diseases related to it. Thanks to the esophageal function test, in addition to the routine various endoscopic anti-reflux procedures, our hospital has taken the lead in China in recent years to carry out a series of clinical and research work for benign esophageal diseases, such as the development of magnetic ring, double nedoscopic combination and new anti-reflux endoscopic techniques. In recent years, we have carried out high-resolution esophageal manometry and 24-hour pH/impedance monitoring for patients with interstitial pneumonia and pulmonary fibrosis suspected to be caused by gastroesophageal acid reflux. We can better assess the correlation between gastroesophageal reflux and pulmonary fibrosis, and to provide the different clinical treatments and even surgical interventions. The Bravo capsule is used more often in the United States, and it has obvious advantages over traditional approach for acid measurement. We strongly call for the collaboration between industry and academic institutions in this field, and the development of our own related products with independent intellectual property rights.

OBJECTIVE: To assess the risk of aristolochic acid (AA)-associated cancer in patients with AA nephropathy (AAN). METHODS: A retrospective study was conducted on patients diagnosed with AAN at Peking University First Hospital from January 1997 to December 2014. Long-term surveillance and follow-up data were analyzed to investigate the influence of different factors on the prevalence of cancer. The primary endpoint was the incidence of liver cancer, and the secondary endpoint was the incidence of urinary cancer during 1 year after taking AA-containing medication to 2014. RESULTS: A total of 337 patients diagnosed with AAN were included in this study. From the initiation of taking AA to the termination of follow-up, 39 patients were diagnosed with cancer. No cases of liver cancer were observed throughout the entire follow-up period, with urinary cancer being the predominant type (34/39, 87.17%). Logistic regression analysis showed that age, follow-up period, and diabetes were potential risk factors, however, the dosage of the drug was not significantly associated with urinary cancer. CONCLUSIONS No cases of liver cancer were observed at the end of follow-up. However, a high prevalence of urinary cancer was observed in AAN patients. Establishing a direct causality between AA and HCC is challenging.
Humans ; Retrospective Studies ; Incidence ; Carcinoma, Hepatocellular ; Liver Neoplasms/epidemiology* ; Kidney Diseases/chemically induced* ; Aristolochic Acids/adverse effects*

Aim To investigate whether diallyl disul-fide (DADS) augments the sensitivity of DJ-1 (protein/ nucleic acid deglycase) overexpressed human gastric SGC7901 cells to 5-FU (5-fluorouracil). Methods The experimental groups include control group, DADS group, VCR (vincristine) group, VCR + DADS group, DJ-1 group, DJ-1 + DADS group. MTT was used to analyze the effect of DADS on 5 -FU (5 -fluorou- racil) induced proliferation inhibition. Flow cytometry was performed to examine the effect of DADS on cell apoptosis. RT-PCR, Western blot, and immunofluo-rescence were used for determine the effect of DADS on the drug resistance associated gene expression. Results DADS enhanced the proliferation inhibitory effect of 5-FU on DJ-1 overexpressed cells and VCR resistant cells. DADS could induce apoptosis in VCR-resistant cells. DADS downregulated the expression of DJ-1 while inducing apoptosis in DJ-1 overexpressed cells. DJ-1 overexpression upregulated the expression of P-gp (P-glycoprotein), Bcl-2, and XIAP (X-linked inhibitor of apoptosis protein), downregulated the expression of caspase-3. DADS decreased the expression of P-gp, Bcl-2, and XIAP, while increased the expression of caspase-3 in DJ-1 overexpressed cells and VCR-resistant cells. Conclusions DADS can augment the sensitivity of DJ-1 overexpressed cells to 5-FU, which is related to its antagonism against DJ-1 mediated upregula- tion of P-gp, Bcl-2, XIAP, and downregulation of caspase-3.

BACKGROUND:Ankylosing spondylitis is a chronic inflammatory disease with chronic rheumatic immunity.Soft tissue ossification and fusion and spinal stiffness can cause biomechanical changes. OBJECTIVE:To reconstruct the lumbar-sacral intervertebral disc in ankylosing spondylitis patients with lumbar kyphosis by finite element analysis,and to study the range of motion of each segment of T11-S1 and the biomechanical characteristics of annulus fibrosus and nucleus pulposus. METHODS:The imaging data were obtained from an ankylosing spondylitis patient with lumbar kyphosis.The original CT image data of continuously scanned spine were imported into Mimics 21.0 in DICOM format,and T11-S1 was reconstructed respectively.The established model was imported into 3-Matic software in the format of"Stl"to reconstruct the intervertebral disc,and the fibrous intervertebral disc model was obtained.The improved model was further imported into Hypermesh software,and the vertebra,nucleus pulposus,annulus fibrosus and ligament were mesh-divided.After the material properties were given,the model was imported into ABAQUS software to observe the range of motion of each vertebral body in seven different working conditions of T11-S1,and analyze the biomechanical characteristics of each segment of annulus fibrosus and nucleus pulposus. RESULTS AND CONCLUSION:(1)The range of motion of L1 vertebrae was higher than that of other vertebrae under six different working conditions:extension,forward flexion,rotation(left and right),and lateral flexion(left and right).The maximum range of motion was 2.18° during L1 vertebral flexion,and the minimum range of motion was 0.12° during L5 vertebral extension.(2)The annular fiber flexion at L2-L3 segments was greater than the extension(P<0.05),and the annular fiber flexion at L3-L4 and L4-L5 segments was less than the extension(P<0.05).The left rotation of L1-L2 annular fibers was greater than the right rotation(P<0.05).The left flexion of the annulus was greater than the right flexion in L1-L2,L2-L3,L3-L4,L4-L5 and L5-S1 segments(P<0.05).(3)The nucleus pulposus stresses of T11-L12,L1-L2,L2-L3,L3-L4 and L4-L5 segments in forward flexion were greater than in extension(P<0.05).The left rotation of T12-L1 and L3-L4 segments was smaller than the right rotation(P<0.05),and that of T11-T12,L1-L2,and L2-L3 segments was larger than the right rotation(P<0.05).The left flexion was larger than the right flexion in the T11-S1 segment.(4)It is concluded that in ankylosing spondylitis patients with lumbar kyphosis,the minimum range of motion of the vertebral body is located at the L5 vertebral body in extension.To prevent fractures,it is recommended to avoid exercise in the extension position.During the onset of lumbar kyphosis in patients with ankylosing spondylitis,the maximum stress of the annulus fibrosus and nucleus pulposus is located in the L1-L2 segment,which is fixed and will not alter with the change of body position.The late surgical treatment and correction of deformity should focus on releasing the pressure of the annulus fibrosus and nucleus pulposus in this segment to avoid the rupture of the annulus fibrosus and the injury of the nucleus pulposus.

BACKGROUND:Ankylosing spondylitis is a progressive inflammation of spinal stiffness deformity caused by tissue ossification and fibrosis.The posture of ankylosing spondylitis patients is abnormal and their activities are limited that minor injuries can lead to thoracolumbar fractures.Traditional medical image observation limits doctors'preoperative decision planning and postoperative disease prevention for ankylosing spondylitis treatment. OBJECTIVE:Based on the spinal model of ankylosing spondylitis patients before and after posterior spinal cancellous ossification osteotomy("Y"osteotomy for short),to explore the biomechanical changes of"Y"osteotomy and fixation in the treatment of ankylosing spondylitis. METHODS:Based on the preoperative and postoperative CT images of an ankylosing spondylitis patient who went to the Second Affiliated Hospital of Inner Mongolia Medical University,a three-dimensional spine model(T11-S1)before and after"Y"osteotomy(L3 osteotomy)was reconstructed in Mimics 19.0 software.A 7.5 Nm torque was applied to the top of T11 vertebral body to simulate the movement of the spine under six conditions:flexion,extension,left bending,right bending,left rotation and right rotation.Finally,the range of motion of each vertebral body,the stress of each intervertebral disc,and the stress of the screw rod system were simulated. RESULTS AND CONCLUSION:(1)After"Y"type osteotomy and posterior fixation,the range of motion of all vertebrae in the spine decreased,and the loss rate of upper vertebrae was large(L1:77.95%).(2)The maximum stress of the spinal intervertebral disc before operation occurred at the L1-L2 segment(0.55 MPa),and the maximum stress of the spinal intervertebral disc after operation occurred at the T11-T12 segment(0.50 MPa),and the stress of intervertebral disc below T12 was far less than that before operation.(3)The maximum stress of the screw rod system(166.67 MPa)occurred in the upper and middle segments of the rod body and the root of the pedicle screw.(4)In conclusion,the"Y"type posterior fixation operation enhances the stability of the spine and reduces the range of motion of the spine.The vertebral body decompression of the fixed segment is great and the stress-shielding phenomenon of the lower vertebral body is significant.The stiffness of the rod body and the stress concentration area of the pedicle screw should be strengthened to avoid the fracture of the rod caused by stress fatigue.

Objective:To investigate the dynamic trend of platelet（PLT）count and mean platelet volume（MPV）in children with severe community-acquired pneumonia（SCAP）in PICU and their correlation with prognosis.Methods:A retrospective study was conducted in 215 SCAP children who were admitted to the PICU of Beijing Children's Hospital Affiliated to Capital Medical University from January 2016 to December 2019.According to the disease outcome，the patients were divided into improvement group ( n=184) and unrecovered group ( n=31).The changes of PLT count and MPV at admission，on the 2nd，3rd，and 7th days of hospitalization and before discharge were observed，and the relationship between changes in PLT parameters and poor prognosis was analyzed. Meanwhile，the correlation between thrombocytopenia on admission and on the 7th day of hospitalization and prognosis was further explored. Results:The PLT count of improvement group at admission，on the 2nd，3rd，and 7th days of hospitalization and at discharge[(328±159, 329±137, 362±159, 439±168, 510±171)×10 9/L] were significantly higher than those of unrecovered group [(210±142, 207±152, 267±143, 260±162, 343±159)×10 9/L]（ P＜0.05）.Although the MPV of improvement group [(10.9±1.9)fL] on admission was significantly lower than that of the unrecovered group[(12.7±2.5) fL]（ P＜0.05），there was no significant difference in MPV between two groups on the 2nd，3rd，7th days of hospitalization and discharge（ P＞0.05）.In addition，compared with the admission，children in improvement group had significantly higher PLT count on the 7th day of hospitalization and before discharge（ P＜0.05），but there was no significant change in unrecovered group（ P＞0.05）.Compared with SCAP patients with thrombocytopenia at admission (PLT＜100×10 9/L)( n=22),those with thrombocytopenia on 7th day of hospitalization had a significant higher rate of non recovery( P＜0.05). Conclusion:The occurrence of thrombocytopenia on admission and after 7 days of hospitalization in children with SCAP is associated with poor prognosis.No significant increase or decrease in PLT count after 7 days of hospitalization is often indicative of poor prognosis.Dynamic monitoring of PLT parameter changes may help to better judge the prognosis of severe pneumonia.

Small molecule drug screening technology is continuously evolving and expanding along with drug discovery,and the innovation in drug screening technology can improve the research and development efficiency and success rate,shorten the cycle time,and reduce the cost.From traditional screening technologies based on known active compounds and high-throughput screening(HTS)to new technologies such as structure-based drug discovery(SBDD),fragment-based drug discovery(FBDD),DNA encoded compound library(DEL)and proteolysis targeting chimeras(PROTAC),small molecule drug screening technologies are continuously broadening the market potential for small molecule drugs.This article will provide an overview of the current status of small molecule drug screening technology,systematically review each technique along with their advantages and disadvantages,and offer essential insights for the development of new small molecule drug screening technologies.

AIM:To investigate the effect of circular RNA MYO9A-006(circMYO9A_006)on hypertrophic phenotype of cardiomyocytes and the underlying mechanism.METHODS:The effect of adenovirus-mediated overexpres-sion of circMYO9A_006 on the expression of hypertrophy-related proteins,including β-myosin heavy chain(β-MHC),skeletal muscle actin alpha 1(ACTA1)and atrial natriuretic peptide(ANP),was evaluated in neonatal mouse ventricular cardiomyocytes(NMVCs).Moreover,a neonatal rat ventricular cardiomyocyte(NRVC)model of phenylephrine(PE)-in-duced hypertrophy was established.The effect of circMYO9A_006 overexpression on NRVC size was ascertained using Phalloidin-iFluor 647 staining method.Dual-luciferase reporter assay was employed to measure the activity of potential in-ternal ribosome entry sites(IRES)in circMYO9A_006.The translation and intracellular location of the circMYO9A_006-translated protein,MYO9A-208aa,were verified using Western blot.To investigate the role of MYO9A-208aa in the ef-fect of circMYO9A_006 on the cardiomyocyte hypertrophic phenotype,we prepared and used the following adenoviruses:the recombinant circMYO9A_006-ORF adenovirus to express MYO9A-208aa,the recombinant circMYO9A_006-ATG-mut adenovirus that does not express MYO9A-208aa,the recombinant circMYO9A_006 adenovirus,and the adenovirus vector control.These were then employed to infect NRVCs.RESULTS:Successful adenovirus-mediated overexpression of circMYO9A_006 was observed in NMVCs.The increased expression of circMYO9A_006 notably reduced the expres-sion of hypertrophy-related proteins in NMVCs(P<0.01).Concurrently,overexpression of circMYO9A_006 substantially reduced the expression of hypertrophy-associated proteins and diminished the size of PE-induced NRVCs(P<0.05).Dual-luciferase reporter assay identified the activity of 2 IRES in circMYO9A_006.Western blot results indicated that circ-MYO9A_006 could produce the MYO9A-208aa protein with an anticipated molecular weight of 28 kD in NRVCs,primari-ly found in the cytoplasm.Elevated expression of both circMYO9A_006 and MYO9A-208aa consistently reduced the ex-pression of hypertrophy-associated proteins(P<0.01),and counteracted the enlarged size of PE-induced NRVCs(P<0.05).However,increased expression of circMYO9A_006-ATG-mut did not counteract the PE-induced hypertrophic phe-notype of NRVCs.CONCLUSION:circMYO9A_006 attenuates the hypertrophic phenotype of cardiomyocytes by synthe-sizing the MYO9A-208aa protein.