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.

Objective To investigate the clinical effect of superficial temporal artery-middle cerebral artery anastomosis(STA-MCA)in the treatment of patients with occlusive cerebrovascular disease.Methods A total of 74 patients with occlusive cerebrovascular disease admitted to our hospital were included and divided into the observation group and control group according to the random number table method,with 37 cases in each group.Patients in the control group received conservative treatment,and patients in the observation group received STA-MCA.After 3 months of follow-up,the cerebral blood flow indexes(including cerebral blood flow of anterior cerebral artery,and peak time)before treatment and 3rd day,1st month and 3rd month after treatment were observed,the modified Rankin scores before treatment and 3rd day and 1 month after treatment were recorded,and the revascularization and occurrence of complications after treatment were recorded.Results At 1 month and 3 months after treatment,the cerebral blood flow of anterior cerebral artery in the two groups increased and the peak time was shortened,and the cerebral blood flow of anterior cerebral artery in the observation group was higher than that in the control group,and the peak time was shorter than that in the control group,with statistically significant differences(P<0.05).The modified Rankin scores of the two groups 1 month after treatment were lower compared with those before treatment,and the modified Rankin score of the observation group was lower than that of the control group,with statistically significant differences(P<0.05).At 1 month after treatment,the proportions of patients with grades 0 and 1 of vascular reconstruction in the observation group were lower than those in the control group,and the proportions of patients with grades 2 and 3 were higher than those in the control group,with statistical significant differences(P<0.05).At 3 months after treatment,the proportions of patients with grades 0 and 1 of vascular reconstruction in the observation group were lower than those in the control group,and the proportion of patients with grade 3 of vascular reconstruction was higher than that in the control group,with statistically significant differences(P<0.05).There was no statistically significant difference in the total incidence of complications after treatment between the two groups(P>0.05).Conclusion STA-MCA has a good clinical effect in the treatment of patients with occlusive cerebrovascular disease,which is conducive to improving the cerebral blood flow indexes and promoting the recovery of neurological function and vascular reconstruction,with safety and reliability.

Objective The purpose of this study was to investigate the bacterial communities of biting midges and ticks collected from three sites in the Poyang Lake area,namely,Qunlu Practice Base,Peach Blossom Garden,and Huangtong Animal Husbandry,and whether vectors carry any bacterial pathogens that may cause diseases to humans,to provide scientific basis for prospective pathogen discovery and disease prevention and control. Methods Using a metataxonomics approach in concert with full-length 16S rRNA gene sequencing and operational phylogenetic unit(OPU)analysis,we characterized the species-level microbial community structure of two important vector species,biting midges and ticks,including 33 arthropod samples comprising 3,885 individuals,collected around Poyang Lake. Results A total of 662 OPUs were classified in biting midges,including 195 known species and 373 potentially new species,and 618 OPUs were classified in ticks,including 217 known species and 326 potentially new species.Surprisingly,OPUs with potentially pathogenicity were detected in both arthropod vectors,with 66 known species of biting midges reported to carry potential pathogens,including Asaia lannensis and Rickettsia bellii,compared to 50 in ticks,such as Acinetobacter lwoffii and Staphylococcus sciuri.We found that Proteobacteria was the most dominant group in both midges and ticks.Furthermore,the outcomes demonstrated that the microbiota of midges and ticks tend to be governed by a few highly abundant bacteria.Pantoea sp7 was predominant in biting midges,while Coxiella sp1 was enriched in ticks.Meanwhile,Coxiella spp.,which may be essential for the survival of Haemaphysalis longicornis Neumann,were detected in all tick samples.The identification of dominant species and pathogens of biting midges and ticks in this study serves to broaden our knowledge associated to microbes of arthropod vectors. Conclusion Biting midges and ticks carry large numbers of known and potentially novel bacteria,and carry a wide range of potentially pathogenic bacteria,which may pose a risk of infection to humans and animals.The microbial communities of midges and ticks tend to be dominated by a few highly abundant bacteria.

To explore the changes and the reaction mechanisms between soil microecological environment and the content of secon-dary metabolites of plants under water deficit, this study carried out a pot experiment on the 3-leaf stage seedlings of Rheum officinale to analyze their response mechanism under different drought gradients(normal water supply, mild, moderate, and severe drought). The results indicated that the content of flavonoids, phenols, terpenoids, and alkaloids in the root of R. officinale varied greatly under drought stresses. Under mild drought stress, the content of substances mentioned above was comparatively high, and the content of rutin, emodin, gallic acid, and(+)-catechin hydrate in the root significantly increased. The content of rutin, emodin, and gallic acid under severe drought stress was significantly lower than that under normal water supply. The number of species, Shannon diversity index, richness index, and Simpson index of bacteria in the rhizosphere soil were significantly higher than those in blank soil, and the number of microbial species and richness index decreased significantly with the aggravation of drought stresses. In the context of water deficit, Cyanophyta, Firmicutes, Actinobacteria, Chloroflexi, Gemmatimonadetes, Streptomyces, and Actinomyces were the dominant bacteria in the rhizosphere of R. officinale. The relative content of rutin and emodin in the root of R. officinale was positively correlated with the relative abundance of Cyanophyta and Firmicutes, and the relative content of(+)-catechin hydrate and(-)-epicatechin gallate was positively correlated with the relative abundance of Bacteroidetes and Firmicutes. In conclusion, appropriate drought stress can increase the content of secondary metabolites of R. officinale from physiological induction and the increase in the association with beneficial microbe.
Rhizosphere ; Rheum ; Droughts ; Soil ; Catechin ; Emodin ; Bacteria/metabolism* ; Water/metabolism* ; Firmicutes ; Soil Microbiology

This study aims to acetylate Rehmannia glutinosa polysaccharides by acetic anhydride method, optimize process parameters and evaluate their antioxidant activity. With the degree of substitution(D_s) as a criterion, the effects of reaction time, acetic anhydride-to-polysaccharides ratio and temperature were investigated. Process parameters were optimized by single-factor experiment and response surface methodology. The infrared spectroscopy(IR) and scanning electron microscopy(SEM) proved the successful acetylation and were employed to preliminarily analyze the structural characteristics of acetylated derivatives. The results showed that the D_s was 0.327 under the optimal technological conditions, including m(acetic anhydride):m(R. glutinosa polysaccharides)=2.70, reaction time 3.0 h and temperature 48 ℃. Further, the antioxidant properties of acetylated derivatives were investigated in vitro and acetylation was found effective to improve the antioxidant activity of R. glutinosa polysaccharides. This study provides a reference for the further development and application of R. glutinosa polysaccharides.
Acetylation ; Antioxidants/pharmacology* ; Polysaccharides/pharmacology* ; Rehmannia/chemistry*

Objective:To explore the possible role and clinical significance of vitamin D receptor (VDR) in intrahepatic bile duct epithelial cells (IBDECs) in biliary atresia (BA).Methods:A retrospective analysis was performed on expression level of VDR in IBDECs of 38 BA children who underwent Kasai surgery in the Second Affiliated Hospital of Xi′an Jiaotong University and the Children′s Hospital of Xi′an Jiaotong University from January 2015 to December 2019.Expression level of VDR in IBDECs of 38 children with BA was detected by immunohistochemical staining, and that in children with choledochal cysts was detected as negative control.Masson staining was performed to examine the degree of liver fibrosis.The correlation between the expression level of VDR in IBDECs of children with BA, and the degree of liver fibrosis during operation, the incidence of refractory cholangitis after Kasai portoenterostomy and the survival time of autologous liver was analyzed.Human intrahepatic bile duct epithelial cells (HiBECs) were induced with dsRNA virus infection by polyinosinic acid-polycytidylic acid [Poly(I∶C)] in vitro, followed by detection of cell activity, apoptosis and VDR level.The differences between 2 independent groups were analyzed using Student t test.The relationship between the expression of VDR and clinicopathologic characteristics was conducted with χ2 test or Fisher′ s test.The Kaplan- Meier survival curve was used to analyze the differences in the survival time of autologous liver after Kasai in BA children with different VDR expression levels. Results:A total of 38 children with BA were included in this study.Among them, 23 cases showed no significant decrease of VDR protein level in IBDECs, and 15 cases showed a significant decrease in IBDECs.Compared with BA children without a significant decrease in VDR level in IBDECs, much severer liver fibrosis ( P<0.001) and significantly higher incidence of refractory cholangitis after Kasai procedure ( P=0.017) were detected in those with a significant decrease in VDR level.Compared with the control group, BA children with significantly lower VDR expression levels in HiBECs had a shorter autologous liver survival time ( P=0.030). Poly (I∶C) increased the apoptotic rate of HiBECs ( P<0.000 1) and decreased cell activity of HiBECs ( P<0.05), which significantly stimulated the secretion of inflammatory factors (interferon, tumor necrosis factor-α, interleukin-6) in the culture medium of HiBECs ( P<0.001). Poly (I∶C) significantly decreased the expression level of VDR protein in HiBECs ( P<0.001). Conclusions:Poly (I∶C) causes HiBECs damage and decreases VDR expression level in HiBECs of BA children, and the significantly decreased VDR expression level in IBDECs may be a marker of poor prognosis of BA.

OBJECTIVES: To explore the influencing factors of the horizontal distance of bodies in the high falling scene and the feasibility of inferring the falling mode based on it. METHODS: A total of 614 high falling deaths and 15 cases of corpse dumping from high altitudes were collected. The relationship between the horizontal distance and the falling height, as well as the sex, age and manner of death (suicide, accident and corpse dumping) were observed. RESULTS: The horizontal distance increased with the increase of falling height, and the difference among the height groups was statistically significant. The horizontal distance decreased with the increase of the age of the deceased, in each height group, the difference between the group over 60 years old and other age groups was statistically significant (P<0.05). The horizontal distance of male deceased was (1.99±0.27) m, which was greater than that of female deceased (1.88±0.19) m, and the difference was statistically significant in partial height groups (P<0.05). Roof falls had a greater horizontal movement distance than window falls. Except for the >20-30 m group, there was no significant difference in horizontal distance between suicide high falls and accidental high falls in other height groups. CONCLUSIONS The horizontal distance is affected by the falling height, the sex and age of the victim, and the spatial characteristics of the falling starting point.
Body Height ; Cadaver ; Female ; Homicide ; Humans ; Male ; Middle Aged ; Suicide

AIM:To evaluate the macular microstructural changes in patients with rhegmatogenous retinal detachment(RRD)after silicone oil tamponade by spectral-domain optical coherence tomography(SD-OCT).METHODS:From November 2019 to July 2021, 27 patients with 27 eyes in RRD who underwent vitrectomy combined with silicone oil tamponade in Cangzhou Aier Eye Hospital were enrolled in this study as the observation group, other 30 healthy volunteers with 30 eyes were included in the control group. The best corrected visual acuity(BCVA)of patients before and after operation were observed, and quantified evaluation of the postoperative macular microstructural changes were performed by SD-OCT.RESULTS: The BCVA(LogMAR)of the observation group at 1wk and 3mo after operation(0.61±0.23, 0.69±0.34)were improved compared with those before operation(1.43±0.77)(all P<0.01). The cube volume and average cube thickness in the macular area at 3mo after operation in the observation group were lower than those at 1wk and 1mo after operation in the control group(all P<0.05). There were no differences in the average ganglion cell-inner plexiform layer(GCIPL)thickness, minimum GCIPL thickness, average macular retinal nerve fiber layer(mRNFL)thickness and minimum mRNFL thickness at 1wk, 1 and 3mo after operation in the observation group, but all decreased compared with the control group(all P<0.01). There were 9 eyes with subretinal fluid(SRF)in the observation group during postoperative follow-up, SRF had a tendency to be gradually absorbed, but 1 eye had a secondary macular hole; 3 eyes had ellipsoid zone disruption, which had a tendency to be gradually repaired; 2 eyes had submacular perfluorocarbon liquid; 2 eyes had macular edema.CONCLUSION: SD-OCT can show the microstructure and morphological changes very well in macular area in patients with RRD after silicone oil tamponade, and has important clinical value for the preoperative and postoperative follow-up evaluation of RRD.

The global pandemic of coronavirus disease 2019 (COVID-19) has brought great challenges to the traditional medical model. During the outbreak of COVID-19 in Shanghai, China, from March to May, 2022, there was a significant increase in the number of pediatric cases due to high transmissibility, immune escape, and vaccine breakthrough capacity of Omicron variants. The designated hospitals for children with COVID-19 served as a connecting link between children's specialized hospitals and mobile cabin hospitals. From April 7 to June 2, 2022, a total of 871 children with COVID-19 were admitted to Renji Hospital, Shanghai Jiao Tong University School of Medicine (South Branch), a designated hospital for children with COVID-19. Among these patients, 568 (65.2%) were children under 3 years old, 870 (99.9%) were mild or moderate, and 1 was severe. This article reports the experience in the management of pediatric cases in this designated hospital, which included the following aspects: establishing an optimal case-admission process; strengthening multidisciplinary standardized diagnosis and treatment; optimizing the management, warning, and rescue system for severe COVID-19; implementing family-centered nursing care; formulating an individualized traditional Chinese medicine treatment regimen; optimizing the discharge process and strengthening bed turnover; implementing strict whole-process control to reduce the risk of nosocomial infection; constructing a structured medical record system and using information platforms to adapt to the work mode of large-volume cases; conducting scientific research and sharing the experience in diagnosis and treatment.
COVID-19 ; Child ; Child, Preschool ; China ; Hospitals, Pediatric ; Humans ; SARS-CoV-2

Objective: To explore the safety and feasibility of stereotactic radiation therapy (SBRT) strategy for irradiating porcine ventricular septum, see if can provide a preliminary experimental evidence for clinical SBRT in patients with hypertrophic obstructive cardiomyopathy (HOCM). Methods: Five male pigs (39-49 kg, 6 months old) were used in this study. Pigs were irradiated at doses of 25 Gy (n=2) or 40 Gy (n=3). Delineation of the target volume was achieved under the guidance of 3-dimensional CT image reconstruction, and SBRT was then performed on defined target volume of porcine ventricular septum. Blood biomarkers, electrocardiogram and echocardiography parameters were monitored before and after SBRT. Pathological examination (HE staining, Masson staining) was performed on the target and non-target myocardium at 6 months post SBRT. Results: SBRT was successful and all animals survived to the designed study endpoint (6 months) after SBRT. Serum cardiac troponin T (cTnT) level was significantly higher than the baseline level at 1 day post SBRT, and reduced at 1 week after SBRT, but was still higher than the baseline level(P<0.05). Serum N-terminal pro-B type natriuretic peptide (NT-proBNP) was also significantly increased at 1 day post SBRT (P<0.05) and returned to baseline level at 1 week post SBRT. The serum NT-proBNP level was (249±78), (594±37) and (234±46) pg/ml, respectively, and the cTnT was (14±7), (240±40) and (46±34) pg/ml, respectively at baseline, 1 day and 1 week after SBRT in the 40 Gy dose group. The serum NT-proBNP level was (184±20), (451±49) and (209±36) pg/ml, respectively, the cTnT values ​​were (9±1), (176±29) and (89±27) pg/ml, respectively at baseline, 1 day and 1 week after SBRT in the 25 Gy dose group. Both NT-proBNP and cTnT values tended to be higher post SBRT in the 40 Gy dose group as compared with the 25 Gy dose group, but the difference was not statistically significant (P>0.05). The left ventricular ejection fraction and the left ventricular end-diastolic diameter remained unchanged before and after SBRT (P>0.05). The interventricular septum thickness showed a decreasing trend at 6 months after SBRT, but the difference was not statistically significant ((9.54±0.24) mm vs. (9.82±8.00) mm, P>0.05). The flow velocity of the left ventricular outflow tract, and the valve function and morphology were not affected by SBRT. At 6 months after SBRT, HE staining revealed necrosis in the irradiated target area of ​​the myocardium in the 40 Gy dose group and the 25 Gy dose group, and the degree of necrosis in the irradiated interventricular septum was more obvious in the 40 Gy dose group as compared with the 25 Gy group. The combined histological analysis of the two groups showed that the necrotic area of ​​the irradiated target area accounted for (26±9)% of the entire interventricular septum area, which was higher than that of the non-irradiated area (0) (P<0.05). There was no damage or necrosis of myocardial tissue outside the target irradiation area in both groups. The results of Masson staining showed that the percentage area of myocardial fibrosis was significantly higher in the irradiated target area than non-irradiated area ((12.6±5.3)% vs. (2.5±0.8)%, P<0.05). Conclusion: SBRT is safe and feasible for irradiating porcine ventricular septum.
Animals ; Feasibility Studies ; Male ; Necrosis ; Radiosurgery/methods* ; Stroke Volume ; Swine ; Ventricular Function, Left ; Ventricular Septum