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1.
Int J Biol Macromol ; 262(Pt 2): 130097, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38342265

RESUMO

To assess the blending effect of field snails with grass carp muscle, the effects of paramyosin (PM) and actomyosin (AM) with different mixture ratios on the gel properties of the binary blend system were investigated in our work. The purified PM from field snail muscle was about 95 kDa on SDS-PAGE. Its main secondary structure was α-helix, which reached to 97.97 %. When the amount of PM increased in the binary blend system, their rheological indices and gel strength were improved. The water holding capacity (WHC) increased to 86.30 % at a mixture ratio of 2:8. However, the WHC and the area of immobile water (P22) dramatically decreased, and the area of free water (P23) increased when the mixture ratio exceeded 4:6. The low level of PM in binary blend system promoted the formation of a homogenous and dense gel network through non-covalent interactions as observed results of SEM and FTIR. When there were redundant PM molecules, the development of heterostructure via hydrophobic interaction of tail-tail contributed to the reduced gel properties of the binary blend system. These findings provided new insight into the binary blend system of PM and AM with different ratios to change the gel properties of myofibrillar protein.


Assuntos
Actomiosina , Tropomiosina , Animais , Géis/química , Actomiosina/química , Caramujos , Água/química
2.
Pulm Pharmacol Ther ; 84: 102286, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38191068

RESUMO

Pulmonary fibrosis is a progressive and debilitating lung disease characterized by the excessive accumulation of extracellular matrix (ECM) components within the lung parenchyma. However, the underlying mechanism remains largely elusive, and the treatment options available for pulmonary fibrosis are limited. Interleukin 5 receptor, alpha (IL5RA) is a well-established regulator of eosinophil activation, involved in eosinophil-mediated anti-parasitic activities and allergic reactions. Recent studies have indicated additional roles of IL5RA in lung epithelium and fibroblasts. Nevertheless, its involvement in pulmonary fibrosis remains unclear. In present study, we employed single-cell analyses alongside molecular and cellular assays to unveil the expression of IL5RA in lung epithelial cells. Moreover, using both in vitro and in vivo models, we demonstrated a notable upregulation of epithelial IL5RA during the progression of pulmonary fibrosis. This upregulated IL5RA expression subsequently promotes epithelial-mesenchymal transition (EMT), leading to the generation of mesenchymal phenotype with augmented capability for ECM production. Importantly, our findings uncovered that the pro-fibrotic function of IL5RA is mediated by Jak2/STAT3 signaling cascades. Inhibiting IL5RA has the potential to deactivate Jak2/STAT3 and suppress the downstream EMT process and ECM production, thereby offering a promising therapeutic strategy for pulmonary fibrosis.


Assuntos
Fibrose Pulmonar , Humanos , Transição Epitelial-Mesenquimal/fisiologia , Fibrose , Subunidade alfa de Receptor de Interleucina-5/metabolismo , Pulmão/metabolismo , Fibrose Pulmonar/metabolismo , Receptores de Interleucina-5/metabolismo , Fator de Transcrição STAT3/metabolismo
3.
Sci Adv ; 10(1): eadj1741, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38170782

RESUMO

Bacteria can swim upstream in a narrow tube and pose a clinical threat of urinary tract infection to patients implanted with catheters. Coatings and structured surfaces have been proposed to repel bacteria, but no such approach thoroughly addresses the contamination problem in catheters. Here, on the basis of the physical mechanism of upstream swimming, we propose a novel geometric design, optimized by an artificial intelligence model. Using Escherichia coli, we demonstrate the anti-infection mechanism in microfluidic experiments and evaluate the effectiveness of the design in three-dimensionally printed prototype catheters under clinical flow rates. Our catheter design shows that one to two orders of magnitude improved suppression of bacterial contamination at the upstream end, potentially prolonging the in-dwelling time for catheter use and reducing the overall risk of catheter-associated urinary tract infection.


Assuntos
Cateteres Urinários , Infecções Urinárias , Humanos , Cateteres Urinários/microbiologia , Inteligência Artificial , Infecções Urinárias/prevenção & controle , Infecções Urinárias/microbiologia , Bactérias , Escherichia coli , Hidrolases
4.
Proc Natl Acad Sci U S A ; 120(51): e2221680120, 2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38096407

RESUMO

Animals integrate sensory information from the environment and display various behaviors in response to external stimuli. In Caenorhabditis elegans hermaphrodites, 33 types of sensory neurons are responsible for chemosensation, olfaction, and mechanosensation. However, the functional roles of all sensory neurons have not been systematically studied due to the lack of facile genetic accessibility. A bipartite cGAL-UAS system has been previously developed to study tissue- or cell-specific functions in C. elegans. Here, we report a toolkit of new cGAL drivers that can facilitate the analysis of a vast majority of the 60 sensory neurons in C. elegans hermaphrodites. We generated 37 sensory neuronal cGAL drivers that drive cGAL expression by cell-specific regulatory sequences or intersection of two distinct regulatory regions with overlapping expression (split cGAL). Most cGAL-drivers exhibit expression in single types of cells. We also constructed 28 UAS effectors that allow expression of proteins to perturb or interrogate sensory neurons of choice. This cGAL-UAS sensory neuron toolkit provides a genetic platform to systematically study the functions of C. elegans sensory neurons.


Assuntos
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Animais , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Células Receptoras Sensoriais/metabolismo
5.
J Pediatr Pharmacol Ther ; 28(5): 430-438, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38130493

RESUMO

OBJECTIVES: Vancomycin 24-hour area under the curve over minimum inhibitory concentration (AUC/MIC) monitoring has been recommended over trough-based monitoring in pediatric patients. This study compared the proportion of target attainment between vancomycin AUC/MIC and trough-based methods, and identified risk factors for subtherapeutic initial extrapolated targets. METHODS: This was a retrospective, observational study conducted at KK Women's and Children's Hospital (KKH), Singapore. Patients aged 1 month to 18 years with stable renal function who received intravenous vancomycin between January 2014 and October 2017, with at least 2 vancomycin serum concentrations obtained after the first dose of vancomycin, were included. Using a pharmacokinetic software, namely Adult and Pediatric Kinetics (APK), initial extrapolated steady-state troughs and 24-hour AUC were determined by using a one-compartmental model. Statistical tests included Wilcoxon rank sum test, McNemar test, logistic regression, and classification and regression tree (CART) analysis. RESULTS: Of the 82 pediatric patients included, a significantly larger proportion of patients achieved therapeutic targets when the AUC/MIC-based method (24, 29.3%) was used than with the trough-based method (9, 11.0%; p < 0.01). Patients with estimated glomerular filtration rate (eGFR) ≥60 mL/min/1.73 m2 or with age <13 years had an increased risk of obtaining subtherapeutic targets. However, empiric vancomycin doses of 60 mg/kg/day would be sufficient to achieve serum therapeutic targets, using the AUC/MIC-based method. CONCLUSION: The AUC/MIC-based vancomycin monitoring may be preferred because a larger proportion of patients could achieve initial therapeutic targets. Future prospective studies with larger sample size will be required to determine the optimal vancomycin strategy for pediatric patients.

6.
Pacing Clin Electrophysiol ; 46(12): 1635-1642, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37942981

RESUMO

OBJECTIVE: This study aimed to explore the roles of duration and burden of atrial high-rate episode (AHRE) on ischemic stroke in patients with pacemaker implantation. METHODS: Patients with pacemaker implantation for bradycardia from 2013 to 2017 were consecutively enrolled. Data such as gender, age, combined diseases, type of AF, left atrial size, left ventricular size, left ventricular ejection fraction, CHA2 DS2 -VASc score, and anticoagulants were collected. The burden and duration of AHRE based on different interval partition were also recorded in detail to evaluate the impacts on ischemic stroke. Cox regression analysis with time-dependent covariates was conducted. RESULTS: A total of 220 patients with AHRE were enrolled. The average follow-up time was 48.42 ± 17.20 months. Univariate regression analysis showed that diabetes (p = .024), high CHA2 DS2 -VASc score (≥ 2) (p = .021), long mean AHRE burden (p = .011), long maximal AHRE burden (p = .015), long AHRE duration lasting≥48 h (p = .001) or 24 h (p = .001) or 12 h (p = .005) were prone to ischemic stroke. Further multivariate regression analysis showed that long duration of AHRE (≥48 h) (HR 10.77; 95% CI 3.22-55.12; p = .030) were significantly correlated with stroke in patients with paroxysmal AF. There was no significant correlation between the type of AF and stroke (p = .927). CONCLUSION: The longer duration of AHRE (≥48 h) was more favorable in predicting ischemic stroke than high CHA2 DS2 -VASc score (≥2).


Assuntos
Fibrilação Atrial , AVC Isquêmico , Humanos , Medição de Risco , Fatores de Risco , Volume Sistólico , Função Ventricular Esquerda
7.
Onco Targets Ther ; 16: 913-922, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38021444

RESUMO

Objective: GW4869 is an exosomal inhibitor. It is necessary to delay the occurrence of gefitinib resistance during non-small-cell lung cancer (NSCLC) treatment. This study aimed to investigate the anti-tumor effects of GW4869 on epithelial-mesenchymal transition (EMT) and expression of extracellular heat shock protein 90α (eHSP90α) that contributes to acquired resisitance. Our study provides a new sight into the treatment of EGFR-mutated NSCLC. Materials and Methods: We performed western blotting to detect levels of EMT and eHSP90α. Wound healing and transwell assays were performed to evaluate the behavioral dynamics of EMT. A nude mouse model of HCC827 was established in vivo. Results: GW4869 inhibited the expression of eHSP90α, EMT, invasion and migration abilities of HCC827 and PC9. GW4869 enhanced sensitivity to gefitinib in BALB/c nude mice bearing tumors of HCC827. Conclusion: These studies suggest that GW4869 can inhibit EMT and extracellular HSP90α, providing new strategies for enhancing gefitinib sensitivity in NSCLC.

8.
Foods ; 12(8)2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-37107512

RESUMO

In the present study, the cuticular wax morphology, composition and the relationship with storage quality in three plum cultivars of Prunus salicina 'Kongxin' (KXL), Prunus salicina 'Fengtang' (FTL) and Prunus salicina 'Cuihong' (CHL) were investigated during storage at room temperature of 25 ± 1 °C. The results illustrated that the highest cuticular wax concentration was discovered in KXL, followed by FTL and the lowest in CHL. The fruit wax composition of the three plum cultivars was similar and principally composed of alkanes, alcohols, fatty acids, ketones, aldehydes, esters, triterpenes and olefins. Alcohols, alkanes and triterpenes were the dominant fruit wax compounds of the three plum cultivars. After storage for 20 d at room temperature, the variation of cuticular wax crystal structure and composition showed significant cultivar-associated differences. The total wax content decreased for FTL and CHL and increased for KXL, and the wax crystal degraded and melted together over time. The higher contents of the main components in the three plum cultivars were nonacosane, 1-triacontanol, 1-heneicosanol, nonacosan-10-one, octacosanal, ursolic aldehyde and oleic acid. Alcohols, triterpenes, fatty acids and aldehydes were most dramatically correlated with the softening of fruit and storage quality, and alkanes, esters and olefins were most significantly correlated with the water loss. Nonacosane and ursolic aldehyde can enhance the water retention of fruit. Overall, this study will provide a theoretical reference for the further precise development of edible plum fruit wax.

9.
Foods ; 12(7)2023 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-37048235

RESUMO

Botryosphaeria dothidea is the source of the deadly kiwifruit disease known as soft rot. In order to explore the role of melatonin in regulating the postharvest quality and disease resistance of kiwifruit at different growth and development stages, in this study, we applied melatonin at different concentrations to kiwifruit at the young fruit, expansion, and late expansion stages to assess its effect on fruit resistance to B. dothidea, minimize soft rot, and maintain postharvest fruit quality. The results showed that melatonin significantly suppressed the mycelial growth of B. dothidea, with 1.0 mmol/L melatonin inhibiting it by up to 50%. However, 0.1-0.3 mmol/L melatonin had the best control over soft rot. Furthermore, spraying MT during kiwifruit growth can successfully increase fruit weight; preserve postharvest fruit firmness; reduce respiration intensity in the early stages of storage; delay the rise in soluble solids, while maintaining a high titratable acid content to ensure suitable solid acid ratio; increase total phenol, flavonoid, chlorophyll, carotenoid, and ascorbic acid contents; and delay the rise in soluble sugar contents in the late stages of storage. These results have a positive effect on maintaining the nutritional composition of kiwifruit. However, the effects on weight loss, dry matter content, and soluble protein content were not significant. In addition, the results of the principal component analysis demonstrated that 0.3 mmol/L MT increased kiwifruit's resistance to soft rot while preserving postharvest fruit quality.

10.
J Neural Eng ; 20(2)2023 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-36863014

RESUMO

Objective.Reliable and user-friendly electrodes can continuously and real-time capture the electroencephalography (EEG) signals, which is essential for real-life brain-computer interfaces (BCIs). This study develops a flexible, durable, and low-contact-impedance polyvinyl alcohol/polyacrylamide double-network hydrogel (PVA/PAM DNH)-based semi-dry electrode for robust EEG recording at hairy scalp.Approach.The PVA/PAM DNHs are developed using a cyclic freeze-thaw strategy and used as a saline reservoir for semi-dry electrodes. The PVA/PAM DNHs steadily deliver trace amounts of saline onto the scalp, enabling low and stable electrode-scalp impedance. The hydrogel also conforms well to the wet scalp, stabilizing the electrode-scalp interface. The feasibility of the real-life BCIs is validated by conducting four classic BCI paradigms on 16 participants.Main results.The results show that the PVA/PAM DNHs with 7.5 wt% PVA achieve a satisfactory trade-off between the saline load-unloading capacity and the compressive strength. The proposed semi-dry electrode exhibits a low contact impedance (18 ± 8.9 kΩ at 10 Hz), a small offset potential (0.46 mV), and negligible potential drift (1.5 ± 0.4µV min-1). The temporal cross-correlation between the semi-dry and wet electrodes is 0.91, and the spectral coherence is higher than 0.90 at frequencies below 45 Hz. Furthermore, no significant differences are present in BCI classification accuracy between these two typical electrodes.Significance.Based on the durability, rapid setup, wear-comfort, and robust signals of the developed hydrogel, PVA/PAM DNH-based semi-dry electrodes are a promising alternative to wet electrodes in real-life BCIs.


Assuntos
Interfaces Cérebro-Computador , Couro Cabeludo , Humanos , Álcool de Polivinil , Eletroencefalografia/métodos , Hidrogéis , Eletrodos
11.
J Orthop Res ; 41(4): 737-746, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-35822355

RESUMO

This study aimed to evaluate the performance of a deep-learning model to evaluate knee osteoarthritis using Kellgren-Lawrence grading in real-life knee radiographs. A deep convolutional neural network model was trained using 8964 knee radiographs from the osteoarthritis initiative (OAI), including 962 testing set images. Another 246 knee radiographs from the Far Eastern Memorial Hospital were used for external validation. The OAI testing set and external validation images were evaluated by experienced specialists, two orthopedic surgeons, and a musculoskeletal radiologist. The accuracy, interobserver agreement, F1 score, precision, recall, specificity, and ability to identify surgical candidates were used to compare the performances of the model and specialists. Attention maps illustrated the interpretability of the model classification. The model had a 78% accuracy and consistent interobserver agreement for the OAI (model-surgeon 1 К = 0.80, model-surgeon 2 К = 0.84, model-radiologist К = 0.86) and external validation (model-surgeon 1 К = 0.81, model-surgeon 2 К = 0.82, model-radiologist К = 0.83) images. A lower interobserver agreement was found in the images misclassified by the model (model-surgeon 1 К = 0.57, model-surgeon 2 К = 0.47, model-radiologist К = 0.65). The model performed better than specialists in identifying surgical candidates (Kellgren-Lawrence Stages 3 and 4) with an F1 score of 0.923. Our model not only had comparable results with specialists with respect to the ability to identify surgical candidates but also performed consistently with open database and real-life radiographs. We believe the controversy of the misclassified knee osteoarthritis images was based on a significantly lower interobserver agreement.


Assuntos
Aprendizado Profundo , Cirurgiões Ortopédicos , Osteoartrite do Joelho , Humanos , Osteoartrite do Joelho/diagnóstico por imagem , Joelho , Radiografia
12.
International Eye Science ; (12): 443-448, 2023.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-964246

RESUMO

AIM: To evaluate the efficacy and safety of foveal-sparing internal limiting membrane peeling(FSIP)or complete internal limiting membrane peeling(CMIP)for the treatment of myopic traction maculopathy(MTM)during vitrectomy.METHODS: CNKI, Wanfang, VIP, PubMed, Embase, Cochrane Library, and Web of Science were searched from January 1th 2000 to July 1th 2022, and studies that compared FSIP and CMIP for MTM were collected. The change and recovery rate of best corrected visual acuity(BCVA), incidence of full-thickness macular hole(FTMH), change of central foveal thickness(CFT)and the rate of complete reattachment.RESULTS: A total of 484 eyes from 12 literatures were included, with 203 eyes in the FSIP group and 281 eyes in the CMIP group. The results of Meta-analysis showed that FSIP group were superior to the CMIP group in the mean change of BCVA(SMD=0.52, 95%CI: 0.20~0.85, P=0.002), the improvement rate of BCVA(RR=1.50, 95%CI: 1.22~1.85, P=0.0002)and the incidence of postoperative FTMH(RR=0.23, 95%CI: 0.10~0.54, P=0.0008). There was no statistical difference between the two surgical methods in terms of mean change in CFT(SMD=0.04, 95%CI: -0.19~0.26, P=0.75)and the rate of complete reattachment(RR=1.12, 95%CI: 0.94~1.32, P=0.20).CONCLUSION: FSIP have similar anatomical outcomes compared to CMIP, but FSIP resulted in better visual acuity and lower incidence of postoperative FTMH.

13.
Foods ; 11(24)2022 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-36553714

RESUMO

Cuticular wax is an essential barrier against biological and abiotic stress and is also an important factor affecting fruit storage quality. This paper investigated the effect of melatonin treatment on cuticular wax and the storage quality of plum fruit at low temperature storage of 4 ± 1 °C. 'Kongxin' plum was treated with 150 µmol·L-1 melatonin, dried overnight at room temperature 25 ± 1 °C, and then stored at 4 ± 1 °C for 40 d. The microstructure of the fruit epidermis was examined after 0, 20, and 40 d of storage, and the wax composition and fruit storage quality were measured at 10 d intervals. The results demonstrated that melatonin promoted the disintegration and thickening of rod-shaped waxy crystals of 'Kongxin' plum fruit and inhibited the combination of disintegrated wax and inner wax. Melatonin maintained fruit firmness and decreased the correlation between fruit firmness and other storage quality parameters. The correlation between firmness and wax composition was enhanced. Melatonin promoted long-chain alkanes that were positively correlated with firmness and water retention and strengthened the correlation between the length of the alkane chain and storage quality parameters but reduced the difference between alkane isomers and storage quality parameters.

14.
JMIR Med Inform ; 10(11): e41342, 2022 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-36355417

RESUMO

BACKGROUND: The automatic coding of clinical text documents by using the International Classification of Diseases, 10th Revision (ICD-10) can be performed for statistical analyses and reimbursements. With the development of natural language processing models, new transformer architectures with attention mechanisms have outperformed previous models. Although multicenter training may increase a model's performance and external validity, the privacy of clinical documents should be protected. We used federated learning to train a model with multicenter data, without sharing data per se. OBJECTIVE: This study aims to train a classification model via federated learning for ICD-10 multilabel classification. METHODS: Text data from discharge notes in electronic medical records were collected from the following three medical centers: Far Eastern Memorial Hospital, National Taiwan University Hospital, and Taipei Veterans General Hospital. After comparing the performance of different variants of bidirectional encoder representations from transformers (BERT), PubMedBERT was chosen for the word embeddings. With regard to preprocessing, the nonalphanumeric characters were retained because the model's performance decreased after the removal of these characters. To explain the outputs of our model, we added a label attention mechanism to the model architecture. The model was trained with data from each of the three hospitals separately and via federated learning. The models trained via federated learning and the models trained with local data were compared on a testing set that was composed of data from the three hospitals. The micro F1 score was used to evaluate model performance across all 3 centers. RESULTS: The F1 scores of PubMedBERT, RoBERTa (Robustly Optimized BERT Pretraining Approach), ClinicalBERT, and BioBERT (BERT for Biomedical Text Mining) were 0.735, 0.692, 0.711, and 0.721, respectively. The F1 score of the model that retained nonalphanumeric characters was 0.8120, whereas the F1 score after removing these characters was 0.7875-a decrease of 0.0245 (3.11%). The F1 scores on the testing set were 0.6142, 0.4472, 0.5353, and 0.2522 for the federated learning, Far Eastern Memorial Hospital, National Taiwan University Hospital, and Taipei Veterans General Hospital models, respectively. The explainable predictions were displayed with highlighted input words via the label attention architecture. CONCLUSIONS: Federated learning was used to train the ICD-10 classification model on multicenter clinical text while protecting data privacy. The model's performance was better than that of models that were trained locally.

15.
Nanomaterials (Basel) ; 12(19)2022 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-36234444

RESUMO

Herein we present a facile synthesis of the graphene oxide-decorated binary transition metal oxides of Bi2O3 and MnO2 nanocomposites (Bi2O3/MnO2/GO) and their applications in the voltammetric detection of lead ions (Pb2+) in water samples. The surface morphologies, crystal structures, electroactive surface area, and charge transferred resistance of the Bi2O3/MnO2/GO nanocomposites were investigated through the scanning electron microscopy (SEM), power X-ray diffraction (XRD), cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS) techniques, respectively. The Bi2O3/MnO2/GO nanocomposites were further decorated onto the surface of a glassy carbon electrode (GCE), and Pb2+ was quantitatively analyzed by using square-wave anodic stripping voltammetry (SWASV). We explored the effect of the analytical parameters, including deposition potential, deposition time, and solution pH, on the stripping peak current of Pb2+. The Bi2O3/MnO2/GO nanocomposites enlarged the electroactive surface area and reduced the charge transferred resistance by significant amounts. Moreover, the synergistic enhancement effect of MnO2, Bi2O3 and GO endowed Bi2O3/MnO2/GO/GCE with extraordinary electrocatalytic activity toward Pb2+ stripping. Under optimal conditions, the Bi2O3/MnO2/GO/GCE showed a broad linear detection range (0.01-10 µM) toward Pb2+ detection, with a low limit of detection (LOD, 2.0 nM). The proposed Bi2O3/MnO2/GO/GCE electrode achieved an accurate detection of Pb2+ in water with good recoveries (95.5-105%).

16.
Molecules ; 27(19)2022 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-36235223

RESUMO

The COVID-19 pandemic is caused by SARS-CoV-2; the spike protein is a key structural protein that mediates infection of the host by SARS-CoV-2. In this study, we aimed to evaluate the effects of signal peptide on the secretion and release of SARS-CoV-2 spike protein. Therefore, we constructed a signal peptide deletion mutant and three signal peptide site-directed mutants. The (H) region and (C) region in the signal peptide of L5F-S13I mutant have changed significantly, compared with wild type, L5F and S13I. We demonstrated the effects of signal peptide on the secretion and synthesis of RBD protein, finding that mutation of S13 to I13 on the signal peptide is more conducive to the secretion of RBD protein, which was mainly due to the shift of the signal peptide cleavage site in the mutant S13I. Here, we not only investigated the structure of the N-terminal signal peptide of the SARS-CoV-2 spike protein but also considered possible secretory pathways. We suggest that the development of drugs that target the signal peptide of the SARS-CoV-2 spike protein may have potential to treat COVID-19 in the future.


Assuntos
COVID-19 , Glicoproteína da Espícula de Coronavírus , Humanos , Pandemias , Sinais Direcionadores de Proteínas/genética , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/metabolismo
17.
Viruses ; 14(9)2022 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-36146826

RESUMO

In the context of the COVID-19 pandemic, conducting antibody testing and vaccination is critical. In particular, the continued evolution of SARS-CoV-2 raises concerns about the effectiveness of vaccines currently in use and the activity of neutralizing antibodies. Here, we used the Escherichia coli expression system to obtain nine different SARS-CoV-2 RBD protein variants, including six single-point mutants, one double-point mutant, and two three-point mutants. Western blotting results show that nine mutants of the RBD protein had strong antigenic activity in vitro. The immunogenicity of all RBD proteins was detected in mice to screen for protein mutants with high immunogenicity. The results show that the mutants E484K, E484Q, K417T-E484K-N501Y, and K417N-E484K-N501Y, especially the former two, had better immunogenicity than the wild type. This suggests that site E484 has a significant impact on the function of the RBD protein. Our results demonstrate that recombinant RBD protein expressed in E. coli can be an effective tool for the development of antibody detection methods and vaccines.


Assuntos
COVID-19 , Vacinas Virais , Aminoácidos/genética , Animais , Anticorpos Neutralizantes/química , Anticorpos Antivirais , COVID-19/prevenção & controle , Escherichia coli/genética , Humanos , Camundongos , Proteínas Mutantes/genética , Mutação , Testes de Neutralização , Pandemias , Proteínas Recombinantes , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus
18.
Int J Mol Sci ; 23(17)2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36077367

RESUMO

We previously developed chicken interleukin-1ß (IL-1ß) mutants as single-dose adjuvants that induce protective immunity when co-administered with an avian vaccine. However, livestock such as pigs may require a vaccine adjuvant delivery system that provides long-lasting protection to reduce the need for successive booster doses. Therefore, we developed chitosan-coated alginate microparticles as a carrier for bovine serum albumin (BSA) or porcine IL-1ß (pIL-1ß) and assessed their physical, chemical, and biological properties. Electrospraying of the BSA-loaded alginate microparticles (BSA/ALG MPs) resulted in an encapsulation efficiency of 50%, and those MPs were then coated with chitosan (BSA/ALG/CHI MPs). Optical and scanning electron microscopy, zeta potential analysis, and Fourier transform infrared spectroscopy were used to characterize these MPs. The BSA encapsulation parameters were applied to ALG/CHI MPs loaded with pIL-1ß, which were not cytotoxic to porcine fibroblasts but had enhanced bio-activity over unencapsulated pIL-1ß. The chitosan layer of the BSA/ALG/CHI MPs prevented burst release and facilitated sustained release of pIL-1ß for at least 28 days. In conclusion, BSA/ALG/CHI MPs prepared as a carrier for pIL-1ß may be used as an adjuvant for the formulation of pig vaccines.


Assuntos
Quitosana , Vacinas , Alginatos/química , Animais , Quitosana/química , Ácido Glucurônico/química , Ácido Glucurônico/farmacologia , Ácidos Hexurônicos/química , Ácidos Hexurônicos/farmacologia , Interleucina-1beta , Soroalbumina Bovina/química , Suínos
20.
FASEB J ; 36(8): e22475, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35899478

RESUMO

Recent findings suggest that extracellular heat shock protein 90α (eHSP90α) promotes pulmonary fibrosis, but the underlying mechanisms are not well understood. Aging, especially cellular senescence, is a critical risk factor for idiopathic pulmonary fibrosis (IPF). Here, we aim to investigate the role of eHSP90α on cellular senescence in IPF. Our results found that eHSP90α was upregulated in bleomycin (BLM)-induced mice, which correlated with the expression of senescence markers. This increase in eHSP90α mediated fibroblast senescence and facilitated mitochondrial dysfunction. eHSP90α activated TGF-ß signaling through the phosphorylation of the SMAD complex. The SMAD complex binding to p53 and p21 promoters triggered their transcription. In vivo, the blockade of eHSP90α with 1G6-D7, a specific eHSP90α antibody, in old mice attenuated the BLM-induced lung fibrosis. Our findings elucidate a crucial mechanism underlying eHSP90α-induced cellular senescence, providing a framework for aging-related fibrosis interventions.


Assuntos
Bleomicina , Fibrose Pulmonar Idiopática , Animais , Bleomicina/toxicidade , Senescência Celular , Fibroblastos/metabolismo , Fibrose Pulmonar Idiopática/induzido quimicamente , Fibrose Pulmonar Idiopática/metabolismo , Pulmão/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Fator de Crescimento Transformador beta/metabolismo
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