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 improve the quality standard of Yuanhu Zhitong oral liquid in order to strengthen the quality control of this oral liquid. MethodThin layer chromatography（TLC） was used for the qualitative identification of Corydalis Rhizoma and Angelicae Dahuricae Radix in Yuanhu Zhitong oral liquid by taking tetrahydropalmatine， corydaline reference substances and Corydalis Rhizoma reference medicinal materials as reference， and cyclohexane-trichloromethane-methanol（5∶3∶0.5） as developing solvent， Corydalis Rhizoma was identified using GF254 glass thin layer plate under ultraviolet light（365 nm）. And taking petroleum ether（60-90 ℃） -ether-formic acid（10∶10∶1） as developing solvent， Angelicae Dahuricae Radix was identified using a silica gel G TLC plate under ultraviolet light（305 nm）. High performance liquid chromatography（HPLC） was performed on a Waters XSelect HSS T3 column（4.6 mm×250 mm， 5 μm） with acetonitrile（A）-0.1% glacial acetic acid solution（adjusted pH to 6.1 by triethylamine）（B） as the mobile phase for gradient elution（0-10 min， 20%-30%A； 10-25 min， 30%-40%A； 25-40 min， 40%-50%A； 40-60 min， 50%-60%A）， the detection wavelength was set at 280 nm， then the fingerprint of Yuanhu Zhitong oral liquid was established， and the contents of tetrahydropalmatine and corydaline were determined. ResultIn the thin layer chromatograms， the corresponding spots of Yuanhu Zhitong oral liquid， the reference substances and reference medicinal materials were clear， with good separation and strong specificity. A total of 12 common peaks were identified in 10 batches of Yuanhu Zhitong oral liquid samples， and the peaks of berberine hydrochloride， dehydrocorydaline， glaucine， tetrahydropalmatine and corydaline. The similarities between the 10 batches of samples and the control fingerprint were all >0.90. The results of determination showed that the concentrations of corydaline and tetrahydropalmatine had good linearity with paek area in the range of 0.038 6-0.193 0， 0.034 0-0.170 0 g·L^-1， respectively. The methodological investigation was qualified， and the contents of corydaline and tetrahydropalmatine in 10 batches of Yuanhu Zhitong oral liquid samples were 0.077 5-0.142 9、0.126 1-0.178 2 g·L^-1， respectively. ConclusionThe established TLC， fingerprint and determination are simple， specific and reproducible， which can be used to improve the quality control standard of Yuanhu Zhitong oral liquid.

Currently, the gut-organ axis has become a hot research topic. As increasing attention has been paid to the role of gut microbiota in the health of organs, the complex and integrated dialogue mechanism between the gastrointestinal tract and the associated microbiota has been demonstrated in more and more studies. Skin as the largest organ in the human body serves as the primary barrier protecting the human body from damage. The proposal of the gut-skin axis has established a bidirectional link between the gut and the skin. The disturbance of gut microbiota can lead to the occurrence of skin diseases, the mechanism of which is complex and may involve multiple pathways in immunity, metabolism, and internal secretion. According to the theory of traditional Chinese medicine(TCM), the connection between the intestine and the skin can be established through the lung, and the interior disorders will definitely cause symptoms on the exterior. This paper reviews the research progress in the gut-skin axis and its correlation with TCM theory and provides ideas and a basis for cli-nical treatment and drug development of skin and intestinal diseases.
Humans ; Medicine, Chinese Traditional ; Gastrointestinal Tract ; Skin Diseases/drug therapy* ; Gastrointestinal Microbiome

Objective:To find the preferences of nursing staff when they provide " Internet + nursing service" for elderly patients.Methods:By means of the discrete choice experiment, a questionnaire was designed to investigate the preferences of nursing staff when they provide " Internet + nursing services" for elderly patients. In-service nursing staff from 8 medical and health institutions in Ningbo city and Wenzhou city were selected by random sampling, for an online questionnaire survey conducted from May to June 2022. The preferences of nursing staff on their service income, service content, service distance, service continuity and residence status of elderly patients when providing " Internet + nursing service" were analyzed by mixed logit regression.Results:A total of 420 valid questionnaires were collected. Compared to 50 yuan/order, nursing staff preferred to a price of 150 yuan/order ( β= 1.22, P<0.001) nursing services; Compared to specialized nursing services, nursing staff preferred to the routine care ( β= 0.86, P<0.001) and health promotion ( β= 0.86, P<0.05) service; Compared to<5 km, nursing staff were unwilling to provide nursing services for elderly patients at distances of 5-10 km and 11-15 km ( β=-0.66, P<0.05; β=-0.95, P<0.001) ; Compared to 1-2 visits per month, nursing staff preferred not to provide continuing care services ( β=-0.70, P<0.05); Compared to homestay with the patient family, nursing staff preferred to provide nursing services for elderly patients residing in nursing homes ( β= 1.21, P<0.001) . Conclusions:Considering the preference of nursing staff tend to provide " Internet + nursing service" for the elderly patients with services featuring appropriate price, non-specialist care, close distance, low continuity (moderate intensity used as the reference) and security assurance for practice.

Humans ; White Matter/pathology* ; Central Nervous System Neoplasms/pathology* ; Lymphoma, Large B-Cell, Diffuse/pathology*

Objective:To construct and validate a prediction model for the risk of intermediate cesarean delivery for primiparous women with failed vaginal trial of labor.Methods:Clinical data of 6 128 pregnant women who gave birth in the Affiliated Hospital of Jining Medical College from January 2019 to December 2020 were collected. The puerpera was randomly divided into train set ( n=4 290) and validation set ( n=1 838). The factors influencing the conversion to cesarean section in primiparous women with failed vaginal trial of labor were analyzed with univariate and binary multivariate logistic regression, and a risk prediction model was established based on the influencing factors. The predictive power of the model was assessed by receiver operating characteristic (ROC) curve and the Hosmer-Lemeshow goodness-of-fit test in train set and validation set. Results:Among 6 128 pregnant women 1 042 cases failed in vaginal trial of labor and were transferred to cesarean section. Univariate analysis showed age, occupation, gestational weight gain, days of gestation, body temperature before delivery, fetal heart condition at delivery, fetal abdominal circumference, Bishop score, premature rupture of membranes, gestational illness, mode of induction of labor, labor analgesia, and fetal orientation were significantly associated with converting to cesarean delivery (all P<0.05). The multivariate binary logistic regression analysis showed that the age, gestational weight gain, body temperature, gestational co-morbidities, days of gestation, premature rupture of membranes, amniotic fluid contamination, induction of labor, and abnormal occipital position were independent risk factors for intermediate cesarean delivery ( OR=1.03-8.06, all P<0.05); while height, occupation, Bishop score, and labor analgesia were protective factors for intermediate cesarean delivery ( OR=0.17-0.96, all P<0.05). A risk prediction model was constructed based on the risk factors and protective factors. In train set, the area under the ROC curve(AUC) of the model was 0.902 (95% CI: 0.89-0.92, P<0.001), with the best cutoff value of 0.138, the sensitivity and specificity were 0.837 and 0.825, respectively; and the Hosmer-Lemeshow goodness-of-fit test showed P=0.192. In validation set the AUC of the model was 0.917 (95% CI: 0.90-0.93, P<0.001), and the sensitivity and specificity were 0.826 and 0.851, respectively; the total correct rate of the model was 87.21% (1 603/1 838). Conclusion:The risk prediction model of failed vaginal trial of labor in primiparous women for intermediate cesarean delivery constructed in this study has good clinical prediction efficacy and high correctness rate.

Objective: The pandemic of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been engendering enormous hazards to the world. We obtained the complete genome sequences of SARS-CoV-2 from imported cases admitted to the Guangzhou Eighth People's Hospital, which was appointed by the Guangdong provincial government to treat coronavirus disease 2019 (COVID-19). The SARS-CoV-2 diversity was analyzed, and the mutation characteristics, time, and regional trend of variant emergence were evaluated. Methods: In total, 177 throat swab samples were obtained from COVID-19 patients (from October 2020 to May 2021). High-throughput sequencing technology was used to detect the viral sequences of patients infected with SARS-CoV-2. Phylogenetic and molecular evolutionary analyses were used to evaluate the mutation characteristics and the time and regional trends of variants. Results: We observed that the imported cases mainly occurred after January 2021, peaking in May 2021, with the highest proportion observed from cases originating from the United States. The main lineages were found in Europe, Africa, and North America, and B.1.1.7 and B.1.351 were the two major sublineages. Sublineage B.1.618 was the Asian lineage (Indian) found in this study, and B.1.1.228 was not included in the lineage list of the Pangolin web. A reasonably high homology was observed among all samples. The total frequency of mutations showed that the open reading frame 1a (ORF1a) protein had the highest mutation density at the nucleotide level, and the D614G mutation in the spike protein was the commonest at the amino acid level. Most importantly, we identified some amino acid mutations in positions S, ORF7b, and ORF9b, and they have neither been reported on the Global Initiative of Sharing All Influenza Data nor published in PubMed among all missense mutations. Conclusion These results suggested the diversity of lineages and sublineages and the high homology at the amino acid level among imported cases infected with SARS-CoV-2 in Guangdong Province, China.
Amino Acids ; COVID-19/epidemiology* ; Genomics ; Humans ; Mutation ; Phylogeny ; SARS-CoV-2/genetics*

Cyclin-dependent kinase 9 (CDK9) activity is correlated with worse outcomes of triple-negative breast cancer (TNBC) patients. The heterodimer between CDK9 with cyclin T1 is essential for maintaining the active state of the kinase and targeting this protein-protein interaction (PPI) may offer promising avenues for selective CDK9 inhibition. Herein, we designed and generated a library of metal complexes bearing the 7-chloro-2-phenylquinoline CˆN ligand and tested their activity against the CDK9-cyclin T1 PPI. Complex 1 bound to CDK9 via an enthalpically-driven binding mode, leading to disruption of the CDK9-cyclin T1 interaction in vitro and in cellulo. Importantly, complex 1 showed promising anti-metastatic activity against TNBC allografts in mice and was comparably active compared to cisplatin. To our knowledge, 1 is the first CDK9-cyclin T1 PPI inhibitor with anti-metastatic activity against TNBC. Complex 1 could serve as a new platform for the future design of more efficacious kinase inhibitors against cancer, including TNBC.

Objective To investigate the relationship between changes in protein tyrosine kinase 7 (PTK7) and receptor tyrosine kinase-like orphan receptor 2 ( ROR2) expression in the brainstem and the pathogenesis of amyotrophic lateral sclerosis (ALS). Methods Forty-four human superoxide dismutase 1( hSODl)-G93A mutant ALS transgenic mice were selected, and an equal number of wild-type littermates was used as control. The brainstems were isolated at da)' 70, day 95, day 108 and da)' 122 after birth, and the morphology of frypoglossal nucleus (12N) and nucleus of facial nerve(7N) neurons in the brainstem of the model mice were observed by Nissl staining. The mRNA and protein expression of PTK7 and ROR2 were detected by RT-PCR and Western blotting respectively, and the cellular localization and distribution of PTK7 and ROR2 in 12N and 7N were observed by immunofluorescence double-labeling technique. Results The result of Nissl staining showed that Nissl bodies in the neurons reduced distinctly with vacuolar degeneration of neurons, cell body atrophy and nuclear volume reduction in the 12N and 7N brainstems of ALS transgenic mice. RT-PCR result indicated that ROR2 and PTK7 mRNA level in the brainstem of ALS transgenic mice were up-regulated at da)' 70, da)' 95, day 108 and day 122 compared with wild-type littermates. Western blotting result showed that PTK7 protein was up-regulated at day 70, day 95, day 108 and day 122, ROR2 protein was up-regulated at day 70, day 95, day 108, and down-regulated at day 122 in the brainstem of ALS transgenic mice compared with wild-type littermates. Immunofluorescence result showed that ROR2/neuronal nuclei (NeuN)and PTK7/NeuN double positive cells, ROR2/glial fibrillary acidic protein (GFAP) and PTK7/GFAP double positive cells were observed in the 12N and 7N of the brainstem of ALS transgenic mice and wild-type mice, suggesting that ROR2 and PTK7 were expressed both in neurons and astrocytes. Conclusion PTK7 and ROR2 are abnormally expressed in the brainstem of ALS transgenic mice, which is closely related to the pathogenesis of ALS.