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1.
Immunity ; 54(7): 1611-1621.e5, 2021 07 13.
Article in English | MEDLINE | ID: mdl-34166623

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants continue to emerge during the global pandemic and may facilitate escape from current antibody therapies and vaccine protection. Here we showed that the South African variant B.1.351 was the most resistant to current monoclonal antibodies and convalescent plasma from coronavirus disease 2019 (COVID-19)-infected individuals, followed by the Brazilian variant P.1 and the United Kingdom variant B.1.1.7. This resistance hierarchy corresponded with Y144del and 242-244del mutations in the N-terminal domain and K417N/T, E484K, and N501Y mutations in the receptor-binding domain (RBD) of SARS-CoV-2. Crystal structure analysis of the B.1.351 triple mutant (417N-484K-501Y) RBD complexed with the monoclonal antibody P2C-1F11 revealed the molecular basis for antibody neutralization and escape. B.1.351 and P.1 also acquired the ability to use mouse and mink ACE2 receptors for entry. Our results demonstrate major antigenic shifts and potential broadening of the host range for B.1.351 and P.1 variants, which poses serious challenges to current antibody therapies and vaccine protection.


Subject(s)
Angiotensin-Converting Enzyme 2/metabolism , Antibodies, Neutralizing/immunology , Immune Evasion , SARS-CoV-2/immunology , Animals , Antibodies, Monoclonal/chemistry , Antibodies, Monoclonal/immunology , Antibodies, Neutralizing/chemistry , Antigenic Variation/genetics , COVID-19/immunology , COVID-19/virology , Host Specificity , Humans , Immune Evasion/genetics , Mice , Mink , Mutation , Protein Binding , SARS-CoV-2/genetics , SARS-CoV-2/physiology , Spike Glycoprotein, Coronavirus/chemistry , Spike Glycoprotein, Coronavirus/genetics , Spike Glycoprotein, Coronavirus/immunology , Spike Glycoprotein, Coronavirus/metabolism , Virus Internalization
2.
Nature ; 581(7807): 215-220, 2020 05.
Article in English | MEDLINE | ID: mdl-32225176

ABSTRACT

A new and highly pathogenic coronavirus (severe acute respiratory syndrome coronavirus-2, SARS-CoV-2) caused an outbreak in Wuhan city, Hubei province, China, starting from December 2019 that quickly spread nationwide and to other countries around the world1-3. Here, to better understand the initial step of infection at an atomic level, we determined the crystal structure of the receptor-binding domain (RBD) of the spike protein of SARS-CoV-2 bound to the cell receptor ACE2. The overall ACE2-binding mode of the SARS-CoV-2 RBD is nearly identical to that of the SARS-CoV RBD, which also uses ACE2 as the cell receptor4. Structural analysis identified residues in the SARS-CoV-2 RBD that are essential for ACE2 binding, the majority of which either are highly conserved or share similar side chain properties with those in the SARS-CoV RBD. Such similarity in structure and sequence strongly indicate convergent evolution between the SARS-CoV-2 and SARS-CoV RBDs for improved binding to ACE2, although SARS-CoV-2 does not cluster within SARS and SARS-related coronaviruses1-3,5. The epitopes of two SARS-CoV antibodies that target the RBD are also analysed for binding to the SARS-CoV-2 RBD, providing insights into the future identification of cross-reactive antibodies.


Subject(s)
Betacoronavirus/chemistry , Peptidyl-Dipeptidase A/chemistry , Peptidyl-Dipeptidase A/metabolism , Receptors, Virus/chemistry , Receptors, Virus/metabolism , Spike Glycoprotein, Coronavirus/chemistry , Spike Glycoprotein, Coronavirus/metabolism , Amino Acid Sequence , Angiotensin-Converting Enzyme 2 , Antibodies, Neutralizing/immunology , Betacoronavirus/metabolism , Binding Sites , Conserved Sequence , Crystallography, X-Ray , Epitopes/chemistry , Epitopes/immunology , Evolution, Molecular , Humans , Hydrogen Bonding , Models, Molecular , Protein Binding , Protein Domains , Severe acute respiratory syndrome-related coronavirus/chemistry , SARS-CoV-2 , Salts/chemistry , Sequence Alignment , Water/analysis , Water/chemistry
3.
Nature ; 584(7819): 115-119, 2020 08.
Article in English | MEDLINE | ID: mdl-32454513

ABSTRACT

The coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) presents a global health emergency that is in urgent need of intervention1-3. The entry of SARS-CoV-2 into its target cells depends on binding between the receptor-binding domain (RBD) of the viral spike protein and its cellular receptor, angiotensin-converting enzyme 2 (ACE2)2,4-6. Here we report the isolation and characterization of 206 RBD-specific monoclonal antibodies derived from single B cells from 8 individuals infected with SARS-CoV-2. We identified antibodies that potently neutralize SARS-CoV-2; this activity correlates with competition with ACE2 for binding to RBD. Unexpectedly, the anti-SARS-CoV-2 antibodies and the infected plasma did not cross-react with the RBDs of SARS-CoV or Middle East respiratory syndrome-related coronavirus (MERS-CoV), although there was substantial plasma cross-reactivity to their trimeric spike proteins. Analysis of the crystal structure of RBD-bound antibody revealed that steric hindrance inhibits viral engagement with ACE2, thereby blocking viral entry. These findings suggest that anti-RBD antibodies are largely viral-species-specific inhibitors. The antibodies identified here may be candidates for development of clinical interventions against SARS-CoV-2.


Subject(s)
Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , Betacoronavirus/immunology , Coronavirus Infections/immunology , Coronavirus Infections/virology , Pneumonia, Viral/immunology , Pneumonia, Viral/virology , Spike Glycoprotein, Coronavirus/immunology , Adult , Aged , Angiotensin-Converting Enzyme 2 , Antibodies, Neutralizing/chemistry , Antibodies, Viral/chemistry , B-Lymphocytes/cytology , B-Lymphocytes/immunology , Betacoronavirus/chemistry , COVID-19 , Child , Clone Cells/cytology , Clone Cells/immunology , Cross Reactions , Crystallization , Crystallography, X-Ray , Female , Humans , Male , Middle Aged , Models, Molecular , Neutralization Tests , Pandemics , Peptidyl-Dipeptidase A/chemistry , Peptidyl-Dipeptidase A/metabolism , Plasma/immunology , SARS-CoV-2 , Spike Glycoprotein, Coronavirus/chemistry , Spike Glycoprotein, Coronavirus/metabolism
4.
Circulation ; 147(3): 212-222, 2023 01 17.
Article in English | MEDLINE | ID: mdl-36335890

ABSTRACT

BACKGROUND: Dual antiplatelet therapy (DAPT) with aspirin as a background therapy has become the standard care after percutaneous coronary intervention. However, some adverse noncardiac effects limited the use of aspirin in clinical practice. Thus, evaluation of pharmacological alternatives to aspirin is attractive. Previous data indicated that indobufen could lessen the unwanted side effects of aspirin while retaining the antithrombotic efficacy, but its combination with a P2Y12 inhibitor still lacks randomized clinical trial evidence. METHODS: In this randomized, open-label, noninferiority trial, patients with negative cardiac troponin undergoing coronary drug-eluting stent implantation were randomly assigned in a 1:1 ratio to receive either indobufen-based DAPT (indobufen 100 mg twice a day plus clopidogrel 75 mg/d for 12 months) or conventional DAPT (aspirin 100 mg/d plus clopidogrel 75 mg/d for 12 months). The primary end point was a 1-year composite of cardiovascular death, nonfatal myocardial infarction, ischemic stroke, definite or probable stent thrombosis, or Bleeding Academic Research Consortium criteria type 2, 3, or 5 bleeding. The end points were adjudicated by an independent Clinical Event Committee. RESULTS: Between January 11, 2018, and October 12, 2020, 4551 patients were randomized in 103 cardiovascular centers: 2258 patients to the indobufen-based DAPT group and 2293 to the conventional DAPT group. The primary end point occurred in 101 patients (4.47%) in the indobufen-based DAPT group and 140 patients (6.11%) in the conventional DAPT group (absolute difference, -1.63%; Pnoninferiority<0.001; hazard ratio, 0.73 [95% CI, 0.56-0.94]; P=0.015). Cardiovascular death, nonfatal myocardial infarction, ischemic stroke, and stent thrombosis were observed in 0.13%, 0.40%, 0.80%, and 0.22% of patients in the indobufen-based DAPT group and 0.17%, 0.44%, 0.83%, and 0.17% of patients in the conventional DAPT group (all P>0.05). The occurrence of Bleeding Academic Research Consortium criteria type 2, 3, or 5 bleeding events was lower in the indobufen-based DAPT group compared with the conventional DAPT group (2.97% versus 4.71%; hazard ratio, 0.63 [95% CI, 0.46-0.85]; P=0.002), with the main decrease in type 2 bleeding (1.68% versus 3.49%; hazard ratio, 0.48 [95% CI, 0.33-0.70]; P<0.001). CONCLUSIONS: In Chinese patients with negative cardiac troponin undergoing drug-eluting stent implantation, indobufen plus clopidogrel DAPT compared with aspirin plus clopidogrel DAPT significantly reduced the risk of 1-year net clinical outcomes, which was driven mainly by a reduction in bleeding events without an increase in ischemic events. REGISTRATION: URL: https://www.chictr.org.cn; Unique identifier: ChiCTR-IIR-17013505.


Subject(s)
Drug-Eluting Stents , Myocardial Infarction , Humans , Aspirin/therapeutic use , Clopidogrel/therapeutic use , Drug Therapy, Combination , Drug-Eluting Stents/adverse effects , Hemorrhage/etiology , Ischemic Stroke/etiology , Myocardial Infarction/drug therapy , Percutaneous Coronary Intervention/adverse effects , Platelet Aggregation Inhibitors/therapeutic use , Thrombosis/etiology , Treatment Outcome , Troponin
5.
Cancer Cell Int ; 24(1): 119, 2024 Mar 30.
Article in English | MEDLINE | ID: mdl-38553712

ABSTRACT

OBJECTIVE: This study aimed to construct a model based on 23 enrolled molecules to evaluate prognoses of pT2/3N0M0 esophageal squamous cell carcinoma (ESCC) patients with up to 20 years of follow-up. METHODS: The lasso-Cox model was used to identify the candidate molecule. A nomogram was conducted to develop the survival model (molecular score, MS) based on the molecular features. Cox regression and Kaplan-Meier analysis were used in this study. The concordance index (C-index) was measured to compare the predicted ability between different models. The primary endpoint was overall survival (OS). RESULTS: A total of 226 patients and 23 proteins were enrolled in this study. Patients were classified into high-risk (MS-H) and low-risk (MS-L) groups based on the MS score of 227. The survival curves showed that the MS-L cohort had better 5-year and 10-year survival rates than the MS-H group (5-year OS: 51.0% vs. 8.0%; 10-year OS: 45.0% vs. 5.0%, all p < 0.001). Furthermore, multivariable analysis confirmed MS as an independent prognostic factor after eliminating the confounding factors (Hazard ratio 3.220, p < 0.001). The pT classification was confirmed to differentiate ESCC patients' prognosis (Log-rank: p = 0.029). However, the combination of pT and MS could classify survival curves evidently (overall p < 0.001), which showed that the prognostic prediction efficiency was improved significantly by the combination of the pT and MS than by the classical pT classification (C-index: 0.656 vs. 0.539, p < 0.001). CONCLUSIONS: Our study suggested an MS for significant clinical stratification of T2/3N0M0 ESCC patients to screen out subgroups with poor prognoses. Besides, the combination of pT staging and MS could predict survival more accurately for this cohort than the pT staging system alone.

6.
Int J Legal Med ; 138(5): 2147-2155, 2024 Sep.
Article in English | MEDLINE | ID: mdl-38760564

ABSTRACT

BACKGROUND & OBJECTIVE: Sex estimation is a critical aspect of forensic expertise. Some special anatomical structures, such as the maxillary sinus, can still maintain integrity in harsh environmental conditions and may be served as a basis for sex estimation. Due to the complex nature of sex estimation, several studies have been conducted using different machine learning algorithms to improve the accuracy of sex prediction from anatomical measurements. MATERIAL & METHODS: In this study, linear data of the maxillary sinus in the population of northwest China by using Cone-Beam Computed Tomography (CBCT) were collected and utilized to develop logistic, K-Nearest Neighbor (KNN), Support Vector Machine (SVM) and random forest (RF) models for sex estimation with R 4.3.1. CBCT images from 477 samples of Han population (75 males and 81 females, aged 5-17 years; 162 males and 159 females, aged 18-72) were used to establish and verify the model. Length (MSL), width (MSW), height (MSH) of both the left and right maxillary sinuses and distance of lateral wall between two maxillary sinuses (distance) were measured. 80% of the data were randomly picked as the training set and others were testing set. Besides, these samples were grouped by age bracket and fitted models as an attempt. RESULTS: Overall, the accuracy of the sex estimation for individuals over 18 years old on the testing set was 77.78%, with a slightly higher accuracy rate for males at 78.12% compared to females at 77.42%. However, accuracy of sex estimation for individuals under 18 was challenging. In comparison to logistic, KNN and SVM, RF exhibited higher accuracy rates. Moreover, incorporating age as a variable improved the accuracy of sex estimation, particularly in the 18-27 age group, where the accuracy rate increased to 88.46%. Meanwhile, all variables showed a linear correlation with age. CONCLUSION: The linear measurements of the maxillary sinus could be a valuable tool for sex estimation in individuals aged 18 and over. A robust RF model has been developed for sex estimation within the Han population residing in the northwestern region of China. The accuracy of sex estimation could be higher when age is used as a predictive variable.


Subject(s)
Asian People , Cone-Beam Computed Tomography , Machine Learning , Maxillary Sinus , Sex Determination by Skeleton , Humans , Male , Female , Adolescent , Maxillary Sinus/diagnostic imaging , Maxillary Sinus/anatomy & histology , Adult , China , Middle Aged , Young Adult , Child , Aged , Sex Determination by Skeleton/methods , Child, Preschool , Support Vector Machine , Ethnicity , Logistic Models , Forensic Anthropology/methods , East Asian People
7.
Environ Res ; 259: 119523, 2024 Oct 15.
Article in English | MEDLINE | ID: mdl-38960352

ABSTRACT

Strengthening rhizosphere effects to enhance pollutant removal is a hotspot of constructed wetlands (CWs) research in recent years, and improving the root traits and metabolic capacity of macrophytes is crucial for strengthening rhizosphere effects. In the field experiment, two types of subsurface flow (SSF) CWs (CW10 and CW20, with substrate depths of 10 and 20 cm, respectively) under the vertical spatial stress of roots (VSSR) and two types of non-VSSR SSF CWs (CW40 and CW60) were adopted with Typha orientalis as cultivated plants to investigate the variability of root development, metabolism, and pollutant removal at different substrate depths. VSSR induced substantial redundant root development, which significantly increased root-shoot ratio, fine and lateral root biomass, root porosity, and root activity, with lateral and fine root biomass of CW20 reaching 409.17 and 237.42 g/m2, respectively, which were 3.18 and 5.28 times those of CW60. The radical oxygen loss (ROL) and dissolved organic carbon (DOC) levels of CW20 single plant were 1.36 and 4.57 times higher than those of CW60, respectively, and more types of root exudates were determined (e.g., aldehydes, ketones and amides). More aerobic heterotrophs (e.g., Massilia, Planomicrobium), nitrification bacteria (e.g., Ellin6067, Nitrospira), aerobic denitrification bacteria (e.g., Bacillu, Chryseobacterium, Pseudomonas) and denitrification phosphorus accumulating organisms (e.g., Flavobacterium) were enriched in the rhizosphere of CW20. This changed the main transformation pathways of pollutants and enhanced the removal of pollutants, with the COD, TN and TP average removal rates of CW20 increasing by 9.99%, 13.28% and 8.92%, respectively, compared with CW60. The ideotype root system architecture CW (RSACW; CW20) constructed in this study, which consists of a large number of fine and lateral roots, can stimulate more efficient rhizosphere effects stably and continuously.


Subject(s)
Biodegradation, Environmental , Plant Roots , Rhizosphere , Wetlands , Plant Roots/microbiology , Plant Roots/metabolism , Plant Roots/growth & development , Typhaceae/metabolism , Water Pollutants, Chemical/metabolism , Waste Disposal, Fluid/methods
8.
Proc Natl Acad Sci U S A ; 118(12)2021 03 23.
Article in English | MEDLINE | ID: mdl-33658332

ABSTRACT

The pandemic of COVID-19, caused by SARS-CoV-2, is a major global health threat. Epidemiological studies suggest that bats (Rhinolophus affinis) are the natural zoonotic reservoir for SARS-CoV-2. However, the host range of SARS-CoV-2 and intermediate hosts that facilitate its transmission to humans remain unknown. The interaction of coronavirus with its host receptor is a key genetic determinant of host range and cross-species transmission. SARS-CoV-2 uses angiotensin-converting enzyme 2 (ACE2) as the receptor to enter host cells in a species-dependent manner. In this study, we characterized the ability of ACE2 from diverse species to support viral entry. By analyzing the conservation of five residues in two virus-binding hotspots of ACE2 (hotspot 31Lys and hotspot 353Lys), we predicted 80 ACE2 proteins from mammals that could potentially mediate SARS-CoV-2 entry. We chose 48 ACE2 orthologs among them for functional analysis, and showed that 44 of these orthologs-including domestic animals, pets, livestock, and animals commonly found in zoos and aquaria-could bind the SARS-CoV-2 spike protein and support viral entry. In contrast, New World monkey ACE2 orthologs could not bind the SARS-CoV-2 spike protein and support viral entry. We further identified the genetic determinant of New World monkey ACE2 that restricts viral entry using genetic and functional analyses. These findings highlight a potentially broad host tropism of SARS-CoV-2 and suggest that SARS-CoV-2 might be distributed much more widely than previously recognized, underscoring the necessity to monitor susceptible hosts to prevent future outbreaks.


Subject(s)
Angiotensin-Converting Enzyme 2/genetics , COVID-19/veterinary , Receptors, Virus/genetics , SARS-CoV-2/genetics , Angiotensin-Converting Enzyme 2/metabolism , Animals , COVID-19/genetics , COVID-19/metabolism , COVID-19/virology , Host Specificity , Humans , Pandemics/prevention & control , Peptidyl-Dipeptidase A/genetics , Peptidyl-Dipeptidase A/metabolism , Phylogeny , Protein Binding , Receptors, Virus/metabolism , Spike Glycoprotein, Coronavirus/genetics , Spike Glycoprotein, Coronavirus/metabolism , Viral Tropism , Viral Zoonoses/genetics , Viral Zoonoses/prevention & control , Viral Zoonoses/virology , Virus Attachment , Virus Internalization
9.
Int J Biometeorol ; 68(5): 843-854, 2024 May.
Article in English | MEDLINE | ID: mdl-38326654

ABSTRACT

This study aimed to investigate the associations between environmental temperature and schizophrenia admissions in Liuzhou, China. A Poisson generalized linear model combined with a distributed lag nonlinear model was used to analyze the effects of daily mean temperature on schizophrenia admissions from 2013 to 2020 in Liuzhou. Additionally, subgroup analyses were conducted to investigate possible modifications stratified by gender, marital status, and age. In this study, 10,420 schizophrenia admissions were included. The relative risks of schizophrenia admissions increased as the temperature rose, and the lag effects of high temperature on schizophrenia admissions were observed when the daily mean temperature reached 21.65°C. The largest single effect was observed at lag0, while the largest cumulative effect was observed at lag6. The single effects of high temperatures on schizophrenia admissions were statistically significant in both males and females, but the cumulative effects were statistically significant only in males, with the greatest effect at lag0-7. The single effect of high temperatures on admissions for unmarried schizophrenics was greatest at lag5, while the maximum cumulative effect for unmarried schizophrenia was observed at lag0-7. The single effects of high temperatures on schizophrenia admissions were observed in those aged 0-20, 21-40, and 41-60. The cumulative effects for schizophrenics aged 21-40 were observed from lag0-3 to lag0-7, with the maximum effect at lag0-7. In conclusion, the risk of schizophrenia admissions increased as the environmental temperature increased. The schizophrenics who were unmarried appeared to be more vulnerable to the single and cumulative effects of high temperature.


Subject(s)
Schizophrenia , Temperature , Humans , Schizophrenia/epidemiology , China/epidemiology , Male , Female , Adult , Middle Aged , Young Adult , Adolescent , Child , Infant , Child, Preschool , Infant, Newborn , Hospitalization/statistics & numerical data , Aged , Marital Status/statistics & numerical data
10.
Am J Otolaryngol ; 45(6): 104474, 2024 Aug 08.
Article in English | MEDLINE | ID: mdl-39137696

ABSTRACT

OBJECTIVE: Early diagnosis of laryngeal cancer (LC) is crucial, particularly in rural areas. Despite existing studies on deep learning models for LC identification, challenges remain in selecting suitable models for rural areas with shortages of laryngologists and limited computer resources. We present the intelligent laryngeal cancer detection system (ILCDS), a deep learning-based solution tailored for effective LC screening in resource-constrained rural areas. METHODS: We compiled a dataset comprised of 2023 laryngoscopic images and applied data augmentation techniques for dataset expansion. Subsequently, we utilized eight deep learning models-AlexNet, VGG, ResNet, DenseNet, MobileNet, ShuffleNet, Vision Transformer, and Swin Transformer-for LC identification. A comprehensive evaluation of their performances and efficiencies was conducted, and the most suitable model was selected to assemble the ILCDS. RESULTS: Regarding performance, all models attained an average accuracy exceeding 90 % on the test set. Particularly noteworthy are VGG, DenseNet, and MobileNet, which exceeded an accuracy of 95 %, with scores of 95.32 %, 95.75 %, and 95.99 %, respectively. Regarding efficiency, MobileNet excels owing to its compact size and fast inference speed, making it an ideal model for integration into ILCDS. CONCLUSION: The ILCDS demonstrated promising accuracy in LC detection while maintaining modest computational resource requirements, indicating its potential to enhance LC screening accuracy and alleviate the workload on otolaryngologists in rural areas.

11.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 55(2): 425-432, 2024 Mar 20.
Article in Zh | MEDLINE | ID: mdl-38645843

ABSTRACT

Objective: To establish quality standards for Liuwei Nengxiao pills, to optimize the quality control method, and to provide references for the quality control of Liuwei Nengxiao pills. Methods: Chebula, dried ginger, and Tibetan liqueur root in Liuwei Nengxiao pills of different batch numbers were analyzed by thin layer chromatography (TLC). Then, the content of chrysophanol in the preparation was determined by high performance liquid chromatography (HPLC). Furthermore, a series of methodological validation, including the investigation of the linear relationship, precision, stability, and reproducibility and sample recovery test, were performed to verify the reliability of the results. Results: The TLC identification method was easy to perform and demonstrated high specificity, clear spots, and good separation effect. In addition, the negative controls showed no interference. The HPLC method showed high accuracy. The results of methodological validation showed that the peak area of chrysophanol had a good linear relationship (r2=1.0) in the range of 0.06-0.80 µg, presenting good precision (with the relative standard deviation being lower than 2.0%), good stability and reproducibility (with the relative standard deviation being lower than 1.0%), and an average recovery rate of 100.8%. Conclusion: TLC and HPLC are easy to perform, showing high accuracy and reproducibility. The quality standards established are scientific, reasonable, stable, and feasible, providing references for the quality control of Liuwei Nengxiao pills.


Subject(s)
Anthraquinones , Drugs, Chinese Herbal , Medicine, Tibetan Traditional , Quality Control , Drugs, Chinese Herbal/standards , Drugs, Chinese Herbal/chemistry , Chromatography, High Pressure Liquid/methods , Medicine, Tibetan Traditional/standards , Chromatography, Thin Layer/methods , Reproducibility of Results
12.
Zhongguo Dang Dai Er Ke Za Zhi ; 26(8): 835-839, 2024 Aug 15.
Article in Zh | MEDLINE | ID: mdl-39148388

ABSTRACT

OBJECTIVES: To study the correlation of anti-C1q antibodies with active systemic lupus erythematosus (SLE) and lupus nephritis (LN) in children, as well as their diagnostic value for active SLE and LN. METHODS: A retrospective selection of 90 hospitalized children with SLE at the Children's Medical Center of Second Xiangya Hospital, Central South University from January 2016 to March 2019 as the SLE group, all of whom were tested for anti-C1q antibodies. A control group was formed by collecting 70 hospitalized children with other autoimmune diseases (OAD) during the same period. The differences in anti-C1q antibody levels were compared between two groups.The correlation of anti-C1q antibodies with various indicators of SLE and LN was analyzed, and the diagnostic value of anti-C1q in SLE and LN was evaluated. RESULTS: The serum levels of anti-C1q antibodies in the SLE group were higher than those in the OAD group (P<0.05). The SLE disease activity index score was positively correlated with anti-C1q antibodies (rs=0.371, P<0.001) and positively correlated with anti-double-stranded DNA antibodies (rs=0.370, P<0.001). The sensitivity and specificity of anti-C1q antibodies for diagnosing active SLE were 89.90% and 53.90%, respectively, with an area under the curve of 0.720 (P<0.05) and a critical value of 5.45 U/mL. The sensitivity and specificity of anti-C1q antibody levels for diagnosing active LN were 58.50% and 85.00%, respectively, with an area under the curve of 0.675 (P<0.05) and a critical value of 22.05 U/mL. CONCLUSIONS: Anti-C1q antibodies can serve as non-invasive biomarkers for evaluating the activity of SLE or predicting the activity of LN in children.


Subject(s)
Complement C1q , Lupus Erythematosus, Systemic , Lupus Nephritis , Humans , Complement C1q/immunology , Lupus Nephritis/immunology , Lupus Nephritis/blood , Female , Child , Male , Lupus Erythematosus, Systemic/immunology , Retrospective Studies , Adolescent , Autoantibodies/blood , Child, Preschool , Antibodies, Antinuclear/blood , Antibodies, Antinuclear/immunology
13.
Zhongguo Dang Dai Er Ke Za Zhi ; 26(8): 823-828, 2024 Aug 15.
Article in Zh | MEDLINE | ID: mdl-39148386

ABSTRACT

OBJECTIVES: To study the clinical characteristics of children with anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). METHODS: A retrospective analysis was conducted on the clinical data of 25 children diagnosed with AAV at the Second Xiangya Hospital of Central South University from January 2010 to June 2022. RESULTS: Among the AAV children, there were 5 males and 20 females, with a median age of onset of 11.0 years. Involvement of the urinary system was seen in 18 cases (72%); respiratory system involvement in 10 cases (40%); skin involvement in 6 cases (24%); eye, ear, and nose involvement in 5 cases (20%); joint involvement in 4 cases (16%); digestive system involvement in 2 cases (8%). Eleven cases underwent kidney biopsy, with 5 cases (46%) showing focal type, 2 cases (18%) showing crescentic type, 2 cases (18%) showing mixed type, and 2 cases (18%) showing sclerotic type. Immune complex deposits were present in 5 cases (45%). Seven cases reached chronic kidney disease (CKD) stage V, with 2 cases resulting in death. Two cases underwent kidney transplantation. At the end of the follow-up period, 2 cases were at CKD stage II, and 1 case was at CKD stage III. Of the 16 cases of microscopic polyangiitis (MPA) group, 13 (81%) involved the urinary system. Of the 9 cases of granulomatosis with polyangiitis (GPA), 6 cases (66%) had sinusitis. Serum creatinine and uric acid levels were higher in the MPA group than in the GPA group (P<0.05), while red blood cell count and glomerular filtration rate were lower in the MPA group (P<0.05). CONCLUSIONS: AAV is more common in school-age female children, with MPA being the most common clinical subtype. The onset of AAV in children is mainly characterized by renal involvement, followed by respiratory system involvement. The renal pathology often presents as focal type with possible immune complex deposits. Children with MPA often have renal involvement, while those with GPA commonly have sinusitis. The prognosis of children with AAV is poor, often accompanied by renal insufficiency.


Subject(s)
Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis , Humans , Female , Male , Child , Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis/complications , Retrospective Studies , Adolescent , Child, Preschool , Renal Insufficiency, Chronic/etiology
14.
Biophys J ; 122(13): 2686-2695, 2023 07 11.
Article in English | MEDLINE | ID: mdl-37226442

ABSTRACT

Salt bridges are important factors in maintaining the stability of proteins, and their contribution to protein folding has received much attention. Although the interaction energies, or stabilizing contributions, of individual salt bridges have been measured in various proteins, a systematic assessment of various types of salt bridges in a relatively uniform environment is still a valuable analysis. Here, we used a collagen heterotrimer as a host-guest platform to construct 48 heterotrimers with the same charge pattern. A variety of salt bridges were formed between the oppositely charged residues Lys, Arg, Asp, and Glu. The melting temperature (Tm) of the heterotrimers was measured with circular dichroism. The atomic structures of 10 salt bridges were shown in three x-ray crystals of heterotrimer. Molecular dynamics simulation based on the crystal structures indicated that strong, intermediate, and weak salt bridges have distinctive N-O distances. A linear regression model was used to predict the stability of heterotrimers with high accuracy (R2 = 0.93). We developed an online database to help readers understand how a salt bridge stabilizes collagen. This work will help us better understand the stabilizing mechanism of salt bridges in collagen folding and provide a new strategy to design collagen heterotrimers.


Subject(s)
Collagen , Molecular Dynamics Simulation , Collagen/metabolism , Circular Dichroism , Protein Folding , Temperature , Thermodynamics , Salts/chemistry
15.
BMC Plant Biol ; 23(1): 299, 2023 Jun 03.
Article in English | MEDLINE | ID: mdl-37268882

ABSTRACT

Grona styracifolia is a photophilous legume that contains abundant flavonoids with multiple pharmacological activities, which is used to cure urethral and biliary calculus in China for thousands of years. The authentication of the rate-limiting enzymes involved in the flavonoids biosynthesis pathway enabled a better understanding of the molecular aspect of quality formation and modulation of this medicinal herb. In this study, the chemical distribution characteristics and content of flavonoids in different tissues of Grona styracifolia were analyzed using ultraperormance liquid chromatography coupled with Q-TOF mass spectrometry and showed that active flavonoids were primarily synthesized and stored in the leaves. Subsequently, RNA sequencing (RNA-seq)-based transcriptome profiling of the different tissues revealed that the flavonoids biosynthesis in the leaves was the most active. Meanwhile, 27 full-length transcripts inferred encoding vital enzymes involved in the flavonoids biosynthesis were preliminarily excavated. Finally, four CHSs, four CHIs, and one FNSII were successfully characterized by heterologous expression, which involved in three rate-limiting steps of the flavonoid biosynthetic pathway. In conclusion, these results laid a foundation for further investigation of the molecular mechanism of the biosynthesis and modulation of active flavonoids in Grona styracifolia.


Subject(s)
Fabaceae , Plants, Medicinal , Transcriptome , Plants, Medicinal/genetics , Plants, Medicinal/metabolism , Gene Expression Profiling , Flavonoids/metabolism , Fabaceae/metabolism , Gene Expression Regulation, Plant
19.
J Virol ; 96(1): e0149221, 2022 01 12.
Article in English | MEDLINE | ID: mdl-34668773

ABSTRACT

The coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has resulted in more than 235 million cases worldwide and 4.8 million deaths (October 2021), with various incidences and mortalities among regions/ethnicities. The coronaviruses SARS-CoV, SARS-CoV-2, and HCoV-NL63 utilize the angiotensin-converting enzyme 2 (ACE2) as the receptor to enter cells. We hypothesized that the genetic variability in ACE2 may contribute to the variable clinical outcomes of COVID-19. To test this hypothesis, we first conducted an in silico investigation of single-nucleotide polymorphisms (SNPs) in the coding region of ACE2. We then applied an integrated approach of genetics, biochemistry, and virology to explore the capacity of select ACE2 variants to bind coronavirus spike proteins and mediate viral entry. We identified the ACE2 D355N variant that restricts the spike protein-ACE2 interaction and consequently limits infection both in vitro and in vivo. In conclusion, ACE2 polymorphisms could modulate susceptibility to SARS-CoV-2, which may lead to variable disease severity. IMPORTANCE There is considerable variation in disease severity among patients infected with SARS-CoV-2, the virus that causes COVID-19. Human genetic variation can affect disease outcome, and the coronaviruses SARS-CoV, SARS-CoV-2, and HCoV-NL63 utilize human ACE2 as the receptor to enter cells. We found that several missense ACE2 single-nucleotide variants (SNVs) that showed significantly altered binding with the spike proteins of SARS-CoV, SARS-CoV-2, and NL63-HCoV. We identified an ACE2 SNP, D355N, that restricts the spike protein-ACE2 interaction and consequently has the potential to protect individuals against SARS-CoV-2 infection. Our study highlights that ACE2 polymorphisms could impact human susceptibility to SARS-CoV-2, which may contribute to ethnic and geographical differences in SARS-CoV-2 spread and pathogenicity.


Subject(s)
Angiotensin-Converting Enzyme 2/genetics , COVID-19/genetics , Genetic Predisposition to Disease/genetics , Angiotensin-Converting Enzyme 2/metabolism , Genetic Variation , Humans , Polymorphism, Single Nucleotide , Protein Binding , SARS-CoV-2/metabolism , SARS-CoV-2/pathogenicity , Spike Glycoprotein, Coronavirus/metabolism , Virus Internalization
20.
PLoS Pathog ; 17(11): e1010053, 2021 11.
Article in English | MEDLINE | ID: mdl-34748603

ABSTRACT

COVID-19 patients transmitted SARS-CoV-2 to minks in the Netherlands in April 2020. Subsequently, the mink-associated virus (miSARS-CoV-2) spilled back over into humans. Genetic sequences of the miSARS-CoV-2 identified a new genetic variant known as "Cluster 5" that contained mutations in the spike protein. However, the functional properties of these "Cluster 5" mutations have not been well established. In this study, we found that the Y453F mutation located in the RBD domain of miSARS-CoV-2 is an adaptive mutation that enhances binding to mink ACE2 and other orthologs of Mustela species without compromising, and even enhancing, its ability to utilize human ACE2 as a receptor for entry. Structural analysis suggested that despite the similarity in the overall binding mode of SARS-CoV-2 RBD to human and mink ACE2, Y34 of mink ACE2 was better suited to interact with a Phe rather than a Tyr at position 453 of the viral RBD due to less steric clash and tighter hydrophobic-driven interaction. Additionally, the Y453F spike exhibited resistance to convalescent serum, posing a risk for vaccine development. Thus, our study suggests that since the initial transmission from humans, SARS-CoV-2 evolved to adapt to the mink host, leading to widespread circulation among minks while still retaining its ability to efficiently utilize human ACE2 for entry, thus allowing for transmission of the miSARS-CoV-2 back into humans. These findings underscore the importance of active surveillance of SARS-CoV-2 evolution in Mustela species and other susceptible hosts in order to prevent future outbreaks.


Subject(s)
Angiotensin-Converting Enzyme 2/metabolism , COVID-19/epidemiology , Host Adaptation , Mink/immunology , Mutation , SARS-CoV-2/isolation & purification , Spike Glycoprotein, Coronavirus/genetics , Adult , Aged , Angiotensin-Converting Enzyme 2/genetics , Animals , Binding Sites , COVID-19/immunology , COVID-19/therapy , COVID-19/transmission , COVID-19/virology , Female , Humans , Immunization, Passive/statistics & numerical data , Male , Middle Aged , Mink/virology , Molecular Dynamics Simulation , Netherlands/epidemiology , Protein Binding , SARS-CoV-2/genetics , Spike Glycoprotein, Coronavirus/metabolism , Virus Internalization , Young Adult , COVID-19 Serotherapy
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