1.Structural and Spatial Analysis of The Recognition Relationship Between Influenza A Virus Neuraminidase Antigenic Epitopes and Antibodies
Zheng ZHU ; Zheng-Shan CHEN ; Guan-Ying ZHANG ; Ting FANG ; Pu FAN ; Lei BI ; Yue CUI ; Ze-Ya LI ; Chun-Yi SU ; Xiang-Yang CHI ; Chang-Ming YU
Progress in Biochemistry and Biophysics 2025;52(4):957-969
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.
2.Mechanism of Aerobic Exercise in Delaying Brain Aging in Aging Mice by Regulating Tryptophan Metabolism
De-Man ZHANG ; Chang-Ling WEI ; Yuan-Ting ZHANG ; Yu JIN ; Xiao-Han HUANG ; Min-Yan ZHENG ; Xue LI
Progress in Biochemistry and Biophysics 2025;52(6):1362-1372
ObjectiveTo explore the molecular mechanism of aerobic exercise to improve hippocampal neuronal degeneration by regulating tryptophan metabolic pathway. Methods60 SPF-grade C57BL/6J male mice were divided into a young group (2 months old, n=30) and a senile group (12 months old, n=30), and each group was further divided into a control group (C/A group, n=15) and an exercise group (CE/AE group, n=15). An aerobic exercise program was used for 8 weeks. Learning memory ability was assessed by Y-maze, and anxiety-depression-like behavior was detected by absent field experiment. Hippocampal Trp levels were measured by GC-MS. Nissl staining was used to observe the number and morphology of hippocampal neurons, and electron microscopy was used to detect synaptic ultrastructure. ELISA was used to detect the levels of hippocampal Trp,5-HT, Kyn, KATs, KYNA, KMO, and QUIN; Western blot was used to analyze the activities of TPH2, IDO1, and TDO enzymes. ResultsGroup A mice showed significant decrease in learning and memory ability (P<0.05) and increase in anxiety and depressive behaviors (P<0.05); all of AE group showed significant improvement (P<0.05). Hippocampal Trp levels decreased in group A (P<0.05) and increased in AE group (P<0.05). Nidus vesicles were reduced and synaptic structures were degraded in group A (P<0.05), and both were significantly improved in group AE (P<0.05). The levels of Trp, 5-HT, KATs, and KYNA were decreased (P<0.05) and the levels of Kyn, KMO, and QUIN were increased (P<0.05) in group A. The activity of TPH2 was decreased (P<0.05), and the activities of IDO1 and TDO were increased (P<0.05). The AE group showed the opposite trend. ConclusionThe aging process significantly reduces the learning memory ability and increases the anxiety-depression-like behavior of mice, and leads to the reduction of the number of nidus vesicles and degenerative changes of synaptic structure in the hippocampus, whereas aerobic exercise not only effectively enhances the spatial learning memory ability and alleviates the anxiety-depression-like behavior of aging mice, but also improves the morphology and structure of neurons in hippocampal area, which may be achieved by the mechanism of regulating the tryptophan metabolic pathway.
3.Investigation of Effect of Different Drying Conditions on Appearance Characteristics and Internal Indicators of Pinelliae Rhizoma Based on Standardization
Suqing LIU ; Xueli ZHANG ; Jing ZHANG ; Cong YANG ; Changfu YANG ; Jun YU ; Bingpeng ZHENG ; Huiwu LI ; Yanhua JIANG ; Chang LIN
Chinese Journal of Experimental Traditional Medical Formulae 2025;31(16):208-215
ObjectiveTo explore the effect of different drying conditions on the appearance and intrinsic quality indicators of Pinelliae Rhizoma for screening suitable drying conditions, so as to provide reference for its standardized production and quality evaluation. MethodsDifferent dried samples of Pinelliae Rhizoma were prepared by lime-assisted sweating method and intermittent drying method. Visual analysis was employed to measure the color brightness values(L*) of the surface, cross-section and powder of the samples, texture analyzer was used to determine the hardness of the samples under different drying conditions. The total starch content was calculated by measuring the contents of amylose and amylopectin in the samples with ultraviolet-visible spectroscopy. High performance liquid chromatography(HPLC) was used to determine the contents of seven nucleoside components(uracil, hypoxanthine, uridine, inosine, guanosine, β-thymidine and adenosine) in the samples. Pearson correlation analysis was conducted to explore the correlation between the external characteristics and intrinsic indicators of the different dried samples. Principal component analysis(PCA) was used to comprehensively rank the data of various indicators, and partial least squares-discriminant analysis(PLS-DA) was used to screen differential components with variable importance in the projection(VIP) value>1. Furthermore, the difference between the optimal drying condition for Pinelliae Rhizoma and the traditional sun-drying method was explored by independent samples t-test. ResultsWith the increase of temperature, the color of the intermittently dried samples gradually deepened, while their hardness gradually decreased. Concurrently, the contents of extract, total starch, uridine and adenosine exhibited an upward trend, whereas the contents of uracil, hypoxanthine and inosine displayed a downward trajectory. Compared with the intermittent drying group, the content of extract in the samples subjected to lime-assisted sweating increased. With the increase of lime dose, the hardness and the total content of nucleoside components in the samples showed a downward trend, while the total starch content showed an upward trend. Correlation analysis showed that the comprehensive score of L* was negatively correlated with the contents of uracil, hypoxanthine and inosine, and positively correlated with the contents of uridine, guanosine and adenosine. Hardness was negatively correlated with adenosine content, and positively correlated with the contents of inosine, uracil and hypoxanthine. Through comprehensive consideration and comprehensive score of principal components, the method of 5% lime-mixed sweating for 6 days emerged as the top-ranking approach. Except for the extract, the results of independent samples t-test showed that there was no significant difference between the 5% lime-mixed sweating for 6 days and the traditional sun-drying in terms of other content indicators. ConclusionThe whiteness and firmness of Pinelliae Rhizoma exhibit significant correlations with its chemical composition, while uridine, uracil, guanosine, adenosine and inosine are the key constituents responsible for the quality difference of Pinelliae Rhizoma under different drying conditions. The lime-assisted sweating method optimized in this study can be proposed as a viable alternative to the traditional sun-drying method. This method not only ensures the quality of the medicinal material but also effectively reduces the drying time and prevents mold contamination, which provides a valuable reference for the standardization of drying conditions and the establishment of quality evaluation criteria for Pinelliae Rhizoma.
4.Single-cell RNA sequencing reveals the process of CA19-9 production and dynamics of the immune microenvironment between CA19-9 (+) and CA19-9 (-) PDAC
Deyu ZHANG ; Fang CUI ; Kailian ZHENG ; Wanshun LI ; Yue LIU ; Chang WU ; Lisi PENG ; Zhenghui YANG ; Qianqian CHEN ; Chuanchao XIA ; Shiyu LI ; Zhendong JIN ; Xiaojiang XU ; Gang JIN ; Zhaoshen LI ; Haojie HUANG
Chinese Medical Journal 2024;137(20):2415-2428
Background::Pancreatic ductal adenocarcinoma (PDAC) is one of the main types of malignant tumor of the digestive system, and patient prognosis is affected by difficulties in early diagnosis, poor treatment response, and a high postoperative recurrence rate. Carbohydrate antigen 19-9 (CA19-9) has been widely used as a biomarker for the diagnosis and postoperative follow-up of PDAC patients. Nevertheless, the production mechanism and potential role of CA19-9 in PDAC progression have not yet been elucidated.Methods::We performed single-cell RNA sequencing on six samples pathologically diagnosed as PDAC (three CA19-9-positive and three CA19-9-negative PDAC samples) and two paracarcinoma samples. We also downloaded and integrated PDAC samples (each from three CA19-9-positive and CA19-9-negative patients) from an online database. The dynamics of the proportion and potential function of each cell type were verified through immunofluorescence. Moreover, we built an in vitro coculture cellular model to confirm the potential function of CA19-9. Results::Three subtypes of cancer cells with a high ability to produce CA19-9 were identified by the markers TOP2A, AQP5, and MUC5AC. CA19-9 production bypass was discovered on antigen-presenting cancer-associated fibroblasts (apCAFs). Importantly, the proportion of immature ficolin-1 positive (FCN1+) macrophages was high in the CA19-9-negative group, and the proportion of mature M2-like macrophages was high in the CA19-9-positive group. High proportions of these two macrophage subtypes were associated with an unfavourable clinical prognosis. Further experiments indicated that CA19-9 could facilitate the transformation of M0 macrophages into M2 macrophages in the tumor microenvironment. Conclusions::Our study described CA19-9 production at single-cell resolution and the dynamics of the immune atlas in CA19-9-positive and CA19-9-negative PDAC. CA19-9 could promote M2 polarization of macrophage in the pancreatic tumor microenvironment.
5.Clinical study of percutaneous transluminal coronary intravascular lithotripsy angioplasty for severe left main coronary artery calcification guided by intravascular ultrasound percutaneous coronary
Feng-Qi LIU ; Jun BAO ; Bai-Hong LI ; Chong-Hao CHEN ; Chang-Zheng GAO ; Yun-Feng GUO ; Xin GU ; Jian-Bin GU ; Xiao-Yan WANG
Chinese Journal of Interventional Cardiology 2024;32(7):383-389
Objective To explore the effectiveness and safety of percutaneous coronary artery shock wave balloon angioplasty(IVL)under the guidance of intravascular ultrasound(IVUS)for the treatment of severe calcification lesions in the left main artery(LM).Methods A total of 26 patients with severe LM(mouth,body,bifurcation)calcification admitted to Jiangnan University Affiliated Hospital from October 2022 to April 2024 were included,with an average age of 72.0(61.8,75.4)years.Under the guidance of IVUS,IVL was used for pre-treatment of calcified lesions,followed by percutaneous coronary intervention(PCI)with stent/drug balloon implantation.All patients were evaluated using IVUS before and after the use of IVL and after PCI.And compare the IVUS intracavity related data before and after treatment[plaque burden(PB)、minimum lumen area(MLA)、minimum lumen diameter(MLD)]and calcification fracture number,minimum stent area(MSA),stent expansion coefficient(expansion,EXP),etc.Results There were 26 patients(2 with opening lesions,7 with body lesions,and 17 with bifurcation lesions at the end of the main trunk),including 7 with stable angina pectoris(SAP),10 with unstable angina(UA),4 with acute ST-segment elevation myocardial infarction(STEMI),and 5 with non ST-segment elevation myocardial infarction(NSTEMI).The PB at the most severe site of calcification decreased by 79.50(76.00,83.75)%compared to 80.00(76.00,83.75)%after IVL(P=0.001),MLA increased by 3.39(3.14,3.68)mm2 compared to 3.38(3.14,3.67)mm2 after IVL(P=0.039),MLD increased by 3.21(3.07,3.30)mm compared to 3.20(3.07,3.30)mm after IVL(P=0.024),and there was 100%calcification rupture(1/2 cases,2/9 cases,≥3/15 cases).The stent/drug ball was successfully implanted 100%,with EXP of(89.15±4.42)%and an MSA of 7.20(6.46,7.45)mm2.No adverse events such as death,angina or recurrent myocardial infarction occurred during the 3 months follow-up after surgery.Conclusions After evaluation by IVUS and pre-treatment with IVL,PCI was successfully completed for severe calcification lesions in LM,and IVL can be used as an option for the treatment of severe calcification in LM.
6.Coronary artery perforation after using shockwave balloon during percutaneous coronary intervention treatment:a case report
Chen-Ji XU ; Fei LI ; Fa ZHENG ; Bin ZHANG ; Feng-Xia QU ; Jian-Meng WANG ; Ya-Qun ZHOU ; Xian-Liang LI ; Song-Tao WANG ; Yan SHAO ; Chang-Hong LU
Chinese Journal of Interventional Cardiology 2024;32(7):405-408
Coronary perforation is when a contrast agent or blood flows outside a blood vessel through a tear in a coronary artery.In this case,we reported a case of percutaneous coronary intervention for coronary calcified lesions,which led to iatrogenic coronary perforation and cardiac tamponade after the use of Shockwave balloon to treat intracoronary calcified nodules,and the management of PCI-related CAP was systematically reviewed through the literature.
7.Isolation,preservation,and biological characteristics analysis of a Listeria bacteriophage
Ling-Yun LIU ; Pan MAO ; Jin-Ni CHEN ; Ling-Ling LI ; Yan WANG ; Jing-Dong SONG ; Zheng-Hong CHEN ; Chang-Yun YE
Chinese Journal of Zoonoses 2024;40(5):435-441
The aim of our research was to obtain Listeria bacteriophages from food and related environments,and conduc-ted the analysis of the electron microscopic morphology,host range specificity,and biological characteristics of the purified phages.The double-layer agar method and the spot test were employed for the isolation and identification of a virulent Listeria phage named LMLPA5,with the isolated strain Listeria in-nocua Lin08 as the host.Phage morphology was observed by transmission electron microscope.The biological characteris-tics of the phage were assessed by determining their host range,optimal multiplicity of infection(MOI),one-step growth curve,and physicochemical stability.Additionally,the preservation efficacy of the phage at 4 ℃,-20 ℃,and-80 ℃ was explored.The phage LMLPA5 belongs to the family Myoviridae based on morphology,exhibiting clear and transparent plaques without halo surrounded.Strains of sever-al Listeria species and different serotypes strains of Listeria monocytogenes were susceptible to lysis by LMLPA5,indica-ting its broad-spectrum activity against Listeria monocytogenes.Optimal MOIs and single-step growth curve analyses revealed optimal MOIs of 0.1 and latent period of 10 minutes for LMLPA5,with average burst size at 95.2 PFU/cell.LMLPA5 was sensitive to high temperatures,and completely inactivated after exposure to 70 ℃ for 1 h,while the phage remained stable for over 32 hours ranging from 4 ℃ to 40 ℃.Within the pH range of 4 to 10,phage titer remained stable and completely inactiva-ted until 60 minutes of ultraviolet exposure.LMLPA5 displayed insensitivity to chloroform,confirming its non-enveloped phage morphology.The phages remained stable for over 8 months when store at 4 ℃ and-80 ℃.The biological characteristics and lysis capacity of phage LMLPA5 were elucidated in this study,which provide the basis for further application.
8.Molecular epidemiological analysis of group A rotavirus in diarrhea cases in children under 5 years of age in Guangdong Province,2021-2022
Cai-Xia LI ; Chang ZHANG ; Wei ZHANG ; Han-Ri ZENG ; Huan-Ying ZHENG ; Bo-Sheng LI ; Bi-Xia KE
Chinese Journal of Zoonoses 2024;40(9):834-840
This study investigated the epidemiological and genotypic characteristics of group A rotavirus(RVA)in children under 5 years of age with diarrhea at a viral diarrhea surveillance sentinel hospital in Guangdong Province from 2021 to 2022,to provide a basis for RVA prevention and control.A total of 1 858 fecal samples from children under 5 years of age with diarrhea in 2021-2022 were collected.Rotavirus antigen was detected with ELISA,and positive samples were further sequenced and categorized.Among the 1 858 samples,156 were RVA positive.The positivity rates in boys and girls were 8.76%and 7.87%,respectively.Significant differences were observed in the detection rates of RVA infection among age groups.The rate of RVA infection increased gradually from December to April of the following year.In 2021,the main endemic strains of RVA in the Guangdong region were of the G9P[8]subtype,and the rare G8P[8]subtype increased in China.In 2022,the G8P[8]subtype surpassed the G9P[8]subtype for the first time.In cases of diarrhea in infants younger than 5 years in Guangdong Province from 2021 to 2022,the RVA genotypes were diverse,the G9P[8]genotype significantly decreased,and the G8P[8]subtype became a dominant genotype.Continuous RVA genotype monitoring remains necessary to assess the risk of RVA-related disea-ses.
9.Simultaneous content determination of ten constituents in Yuejihua Formula Granules by HPLC-MS/MS
Zhi-Jiao LI ; Zhen-Qiu ZHENG ; Xiao-Bo ZHANG ; Chang-Qin GONG
Chinese Traditional Patent Medicine 2024;46(5):1435-1440
AIM To establish an HPLC-MS/MS method for the simultaneous content determination of hyperoside,isoquercitrin,gallic acid,ellagic acid,quercetin,rutin,afzelin,avicularin,quercetin-3-O-6-trans-chumaryl-β-D-glucoside and quercetin 3-O-2″-galloyl-β-D-glucoside in Yuejihua Formula Granules.METHODS The analysis was performed on a 40℃ thermostatic Water Acquisition UPLC ? HSS T3 column(1.8 μm,2.1 mm×150 mm),with the mobile phase comprising of methanol-0.1%formic acid flowing at 0.3 mL/min in a gradient elution manner,and electron spray ionization source was adopted in negative ion scanning with multiple reaction monitoring mode.RESULTS Ten constituents showed good linear relationships within their own ranges(r>0.995 8),whose average recoveries were 97.3%-99.6%with the RSDs of 0.8%-2.7%.CONCLUSION This simple,rapid,sensitive and specific method can be used for the quality control of Yuejihua Formula Granules.
10.Clinical effects of parallel combined flow-through perforator flaps in the treatment of circular hot crush injuries in limbs with blood supply disorder
Shuping ZHOU ; Shimin LI ; Yingguang SHI ; Liwu ZHENG ; Chaonan CHANG ; Junjie CHEN ; Huanpeng WANG ; Ke SUN ; Xiuhuan WANG ; Linbo LIU
Chinese Journal of Burns 2024;40(7):665-672
Objective:To explore the clinical effects of parallel combined flow-through perforator flaps in the treatment of circular hot crush injuries in limbs with blood supply disorder.Methods:The study was a retrospective observational study. From April 2016 to December 2022, 4 cases with circular hot crush injuries in limbs with blood supply disorder were admitted to the Department of Burns and Plastic Surgery of the 988 th Hospital of Joint Logistics Support Force of PLA, including 3 males and 1 female, aged from 24 to 48 years. Among them, 2 cases were injured in the calf and 2 cases were injured in the forearm. After emergency debridement, the area of skin and soft tissue defects was from 20 cm×20 cm to 44 cm×20 cm. The patients had defects in tibialis anterior and posterior tibial arteries with a length of 13 to 18 cm, and in ulnar and radial arteries with a length of 9 to 12 cm. Flaps were designed and cut, including a flow-through anterolateral thigh perforator flap with area of 20 cm×9 cm to 24 cm×21 cm carrying the descending branch of the lateral circumflex femoral artery and the accompanying veins of 8 to 18 cm in length; and a flow-through posterior tibial artery perforator flap with area of 21 cm×13 cm and 20 cm×14 cm carrying the posterior tibial artery, the accompanying veins with a length of 14 and 17 cm respectively, and the great saphenous vein with a length of 22 and 21 cm. The circular hot crush injury wounds in the calf with blood supply disorder were repaired by a parallel combination of flow-through posterior tibial artery perforator flap and flow-through anterolateral thigh perforator flap, and the circular hot crush injury wounds in the forearm with blood supply disorder were repaired by a parallel combination of bilateral flow-through anterolateral thigh perforator flap, and the injured main vessels were reconstructed. The donor site wounds of flap were closed directly or treated with split-thickness skin grafts from abdomen. After surgery, the blood supply and survival of the flap and distal affected limb, the healing of wounds in the donor and recipient sites, the survival of the skin graft in the flap donor site were observed. During follow-up, the condition of flaps, the appearance, blood supply, and function of affected limbs were observed. At the last follow-up, the foot and ankle functions were evaluated according to the scoring standards of American Orthopedic Foot and Ankle Association, and the wrist and hand function was evaluated according to the trial standard of replantation of amputated upper limb function assessment of the Hand Surgery of Chinese Medical Association. Results:The flaps and distal affected limbs of 4 patients had good blood circulation and successfully survived after surgery. The wounds of 3 cases successfully healed, while one patient with circular hot crush injury in the forearm experienced exudation in the recipient site in the later stage, and the wound healed after re-expansion and suturing. The donor site wounds healed smoothly, and the skin grafts successfully survived. During follow-up of 12 to 24 months after surgery, the flaps were slightly swollen, the limbs had good appearance, normal blood circulation, and fine functional recovery. At the last follow-up, the foot and ankle function of 2 patients with circular hot crush injuries in the calf was evaluated as good in 1 case and commonly in 1 case; the wrist and hand function of 2 patients with circular hot crush injuries in the forearm was evaluated as excellent in 1 case and good in 1 case.Conclusions:The parallel combined flow-through perforator flap can reconstruct the damaged main blood vessels and repair the wound at the same time. It can not only effectively save the limb, but also restore part of the function of the affected limb. It is one of the effective methods to treat the circular hot crush injuries in limbs with blood supply disorder.

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