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1.
Anal Chem ; 96(25): 10380-10390, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38860916

RESUMO

To reduce the risk of atherosclerotic disease, it is necessary to not only diagnose the presence of atherosclerotic plaques but also assess the vulnerability risk of plaques. Accurate detection of the reactive oxygen species (ROS) level at plaque sites represents a reliable way to assess the plaque vulnerability. Herein, through a simple one-pot reaction, two near-infrared (NIR) fluorescent dyes, one is ROS responsive and the other is inert to ROS, are coassembled in an amphiphilic amino acid-assembled nanoparticle. In the prepared NIR fluorescent amino acid nanoparticle (named FANP), the fluorescent properties and ROS-responsive behaviors of the two fluorescent dyes are well maintained. Surface camouflage through red blood cell membrane (RBCM) encapsulation endows the finally obtained FANP@RBCM nanoprobe with not only further reduced cytotoxicity and improved biocompatibility but also increased immune escape capability, prolonged blood circulation time, and thus enhanced accumulation at atherosclerotic plaque sites. In vitro and in vivo experiments demonstrate that FANP@RBCM not only works well in probing the occurrence of atherosclerotic plaques but also enables plaque vulnerability assessment through the accurate detection of the ROS level at plaque sites in a reliable ratiometric mode, thereby holding great promise as a versatile tool for the diagnosis and risk assessment of atherosclerotic disease.


Assuntos
Aminoácidos , Corantes Fluorescentes , Nanopartículas , Placa Aterosclerótica , Espécies Reativas de Oxigênio , Placa Aterosclerótica/diagnóstico por imagem , Animais , Espécies Reativas de Oxigênio/metabolismo , Corantes Fluorescentes/química , Nanopartículas/química , Camundongos , Aminoácidos/química , Humanos , Medição de Risco , Imagem Óptica , Raios Infravermelhos , Células RAW 264.7
2.
Mol Nutr Food Res ; : e2300867, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38864846

RESUMO

Vitamin D plays a crucial role in preventing atherosclerosis and in the regulation of macrophage function. This review aims to provide a comprehensive summary of the clinical evidence regarding the impact of vitamin D on atherosclerotic cardiovascular disease, atherosclerotic cerebrovascular disease, peripheral arterial disease, and associated risk factors. Additionally, it explores the mechanistic studies investigating the influence of vitamin D on macrophage function in atherosclerosis. Numerous findings indicate that vitamin D inhibits monocyte or macrophage recruitment, macrophage cholesterol uptake, and esterification. Moreover, it induces autophagy of lipid droplets in macrophages, promotes cholesterol efflux from macrophages, and regulates macrophage polarization. This review particularly focuses on analyzing the molecular mechanisms and signaling pathways through which vitamin D modulates macrophage function in atherosclerosis. It claims that vitamin D has a direct inhibitory effect on the formation, adhesion, and migration of lipid-loaded monocytes, thus exerting anti-atherosclerotic effects. Therefore, this review emphasizes the crucial role of vitamin D in regulating macrophage function and preventing the development of atherosclerosis.

3.
Sci Rep ; 14(1): 10173, 2024 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-38702351

RESUMO

This study aimed to explore the changes of pharmacokinetic parameters after meropenem in patients with abdominal septic shock after gastrointestinal perforation, and to simulate the probability of different dosing regimens achieving different pharmacodynamic goals. The study included 12 patients, and utilized high performance liquid chromatography-tandem mass spectrometry to monitor the plasma concentration of meropenem. The probability of target attainment (PTA) for different minimum inhibitory concentration (MIC) values and %fT > 4MIC was compared among simulated dosing regimens. The results showed that in 96 blood samples from 12 patients, the clearance (CL) of meropenem in the normal and abnormal creatinine clearance subgroups were 7.7 ± 1.8 and 4.4 ± 1.1 L/h, respectively, and the apparent volume of distribution (Vd) was 22.6 ± 5.1 and 17.2 ± 5.8 L, respectively. 2. Regardless of the subgroup, 0.5 g/q6h infusion over 6 h regimen achieved a PTA > 90% when MIC ≤ 0.5 mg/L. 1.0 g/q6h infusion regimen compared with other regimen, in most cases, the probability of making PTA > 90% is higher. For patients at low MIC, 0.5 g/q6h infusion over 6 h may be preferable. For patients at high MIC, a dose regimen of 1.0 g/q6 h infusion over 6 h may be preferable. Further research is needed to confirm this exploratory result.


Assuntos
Antibacterianos , Meropeném , Testes de Sensibilidade Microbiana , Choque Séptico , Humanos , Meropeném/farmacocinética , Meropeném/administração & dosagem , Meropeném/uso terapêutico , Choque Séptico/tratamento farmacológico , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Estudos Prospectivos , Antibacterianos/farmacocinética , Antibacterianos/administração & dosagem , Antibacterianos/uso terapêutico , Adulto , Perfuração Intestinal , Idoso de 80 Anos ou mais
4.
ACS Infect Dis ; 10(6): 2032-2046, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38728322

RESUMO

SARS-CoV-2 spike (S) proteins undergo extensive glycosylation, aiding in proper folding, enhancing stability, and evading host immune surveillance. In this study, we used mass spectrometric analysis to elucidate the N-glycosylation characteristics and disulfide bonding of recombinant spike proteins derived from the SARS-CoV-2 Omicron variant (B.1.1.529) in comparison with the D614G spike variant. Furthermore, we conducted microsecond-long molecular dynamics simulations on spike proteins to resolve how the different N-glycans impact spike conformational sampling in the two variants. Our findings reveal that the Omicron spike protein maintains an overall resemblance to the D614G spike variant in terms of site-specific glycan processing and disulfide bond formation. Nonetheless, alterations in glycans were observed at certain N-glycosylation sites. These changes, in synergy with mutations within the Omicron spike protein, result in increased surface accessibility of the macromolecule, including the ectodomain, receptor-binding domain, and N-terminal domain. Additionally, mutagenesis and pull-down assays reveal the role of glycosylation of a specific sequon (N149); furthermore, the correlation of MD simulation and HDX-MS identified several high-dynamic areas of the spike proteins. These insights contribute to our understanding of the interplay between structure and function, thereby advancing effective vaccination and therapeutic strategies.


Assuntos
Simulação de Dinâmica Molecular , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/metabolismo , Glicoproteína da Espícula de Coronavírus/genética , Glicosilação , SARS-CoV-2/química , SARS-CoV-2/genética , Humanos , Polissacarídeos/química , Polissacarídeos/metabolismo , COVID-19/virologia , Mutação , Conformação Proteica
5.
Anal Chem ; 96(16): 6426-6435, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38604773

RESUMO

Sensors designed based on the trans-cleavage activity of CRISPR/Cas12a systems have opened up a new era in the field of biosensing. The current design of CRISPR/Cas12-based sensors in the "on-off-on" mode mainly focuses on programming the activator strand (AS) to indirectly switch the trans-cleavage activity of Cas12a in response to target information. However, this design usually requires the help of additional auxiliary probes to keep the activator strand in an initially "blocked" state. The length design and dosage of the auxiliary probe need to be strictly optimized to ensure the lowest background and the best signal-to-noise ratio. This will inevitably increase the experiment complexity. To solve this problem, we propose using AS after the "RESET" effect to directly regulate the Cas12a enzymatic activity. Initially, the activator strand was rationally designed to be embedded in a hairpin structure to deprive its ability to activate the CRISPR/Cas12a system. When the target is present, target-mediated strand displacement causes the conformation change in the AS, the hairpin structure is opened, and the CRISPR/Cas12a system is reactivated; the switchable structure of AS can be used to regulate the degree of activation of Cas12a according to the target concentration. Due to the advantages of low background and stability, the CRISPR/Cas12a-based strategy can not only image endogenous biomarkers (miR-21) in living cells but also enable long-term and accurate imaging analysis of the process of exogenous virus invasion of cells. Release and replication of virus genome in host cells are indispensable hallmark events of cell infection by virus; sensitive monitoring of them is of great significance to revealing virus infection mechanism and defending against viral diseases.


Assuntos
Técnicas Biossensoriais , Sistemas CRISPR-Cas , MicroRNAs , Sistemas CRISPR-Cas/genética , Técnicas Biossensoriais/métodos , Humanos , MicroRNAs/análise , MicroRNAs/metabolismo , Regulação Alostérica , Proteínas Associadas a CRISPR/metabolismo , Endodesoxirribonucleases/metabolismo , Endodesoxirribonucleases/química , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Células HEK293
6.
Anal Chem ; 96(6): 2692-2701, 2024 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-38305871

RESUMO

In recent years, the CRISPR/Cas12a-based sensing strategy has shown significant potential for specific target detection due to its rapid and sensitive characteristics. However, the "always active" biosensors are often insufficient to manipulate nucleic acid sensing with high spatiotemporal control. It remains crucial to develop nucleic acid sensing devices that can be activated at the desired time and space by a remotely applied stimulus. Here, we integrated photoactivation with the CRISPR/Cas12a system for DNA and RNA detection, aiming to provide high spatiotemporal control for nucleic acid sensing. By rationally designing the target recognition sequence, this photoactivation CRISPR/Cas12a system could recognize HPV16 and survivin, respectively. We combined the lateral flow assay strip test with the CRISPR/Cas12a system to realize the visualization of nucleic acid cleavage signals, displaying potential instant test application capabilities. Additionally, we also successfully realized the temporary control of its fluorescent sensing activity for survivin by photoactivation in vivo, allowing rapid detection of target nucleic acids and avoiding the risk of contamination from premature leaks during storage. Our strategy suggests that the CRISPR/Cas12a platform can be triggered by photoactivation to sense various targets, expanding the technical toolbox for precise biological and medical analysis. This study represents a significant advancement in nucleic acid sensing and has potential applications in disease diagnosis and treatment.


Assuntos
Técnicas Biossensoriais , Ácidos Nucleicos , Sistemas CRISPR-Cas/genética , Survivina/genética , Biomarcadores , Testes Imediatos
7.
Rapid Commun Mass Spectrom ; 38(5): e9690, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38355883

RESUMO

RATIONALE: Hydrogen/deuterium exchange mass spectrometry (HDX-MS) can provide precise analysis of a protein's conformational dynamics across varied states, such as heat-denatured versus native protein structures, localizing regions that are specifically affected by such conditional changes. Maximizing protein sequence coverage provides high confidence that regions of interest were located by HDX-MS, but one challenge for complete sequence coverage is N-glycosylation sites. The deuteration of peptides post-translationally modified by asparagine-bound glycans (glycopeptides) has not always been identified in previous reports of HDX-MS analyses, causing significant sequence coverage gaps in heavily glycosylated proteins and uncertainty in structural dynamics in many regions throughout a glycoprotein. METHODS: We detected deuterated glycopeptides with a Tribrid Orbitrap Eclipse mass spectrometer performing data-dependent acquisition. An MS scan was used to identify precursor ions; if high-energy collision-induced dissociation MS/MS of the precursor indicated oxonium ions diagnostic for complex glycans, then electron transfer low-energy collision-induced dissociation MS/MS scans of the precursor identified the modified asparagine residue and the glycan's mass. As in traditional HDX-MS, the identified glycopeptides were then analyzed at the MS level in samples labeled with D2 O. RESULTS: We report HDX-MS analysis of the SARS-CoV-2 spike protein ectodomain in its trimeric prefusion form, which has 22 predicted N-glycosylation sites per monomer, with and without heat treatment. We identified glycopeptides and calculated their average isotopic mass shifts from deuteration. Inclusion of the deuterated glycopeptides increased sequence coverage of spike ectodomain from 76% to 84%, demonstrated that glycopeptides had been deuterated, and improved confidence in results localizing structural rearrangements. CONCLUSION: Inclusion of deuterated glycopeptides improves the analysis of the conformational dynamics of glycoproteins such as viral surface antigens and cellular receptors.


Assuntos
COVID-19 , Glicopeptídeos , Humanos , Glicopeptídeos/química , Glicoproteína da Espícula de Coronavírus , Espectrometria de Massas em Tandem/métodos , Deutério , SARS-CoV-2 , Asparagina , Glicoproteínas/química , Polissacarídeos , Íons
8.
ACS Nano ; 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38231016

RESUMO

The spacing between cells has a significant impact on cell-cell interactions, which are critical to the fate and function of both individual cells and multicellular organisms. However, accurately measuring the distance between cell membranes and the variations between different membranes has proven to be a challenging task. In this study, we employ metal-induced energy transfer (MIET) imaging/spectroscopy to determine and track the intermembrane distance and variations with nanometer precision. We have developed a DNA-based molecular adhesive called the DNA nanobrush, which serves as a cellular adhesive for connecting the plasma membranes of different cells. By manipulating the number of base pairs within the DNA nanobrush, we can modify various aspects of membrane-membrane interactions such as adhesive directionality, distance, and forces. We demonstrate that such nanometer-level changes can be detected with MIET imaging/spectroscopy. Moreover, we successfully employed MIET to measure distance variations between a cellular plasma membrane and a model membrane. This experiment not only showcases the effectiveness of MIET as a powerful tool for accurately quantifying membrane-membrane interactions but also validates the potential of DNA nanobrushes as cellular adhesives. This innovative method holds significant implications for advancing the study of multicellular interactions.

9.
BMC Cancer ; 23(1): 1172, 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38037076

RESUMO

OBJECTIVE: There is a lack of standard salvage treatment options for recurrent or metastatic nasopharyngeal carcinoma (RM-NPC) that has failed platinum-containing regimens. Breakthroughs in immunotherapy have opened up new options for these patients. However, the efficacy and safety of immunotherapy have not been clarified. This study aimed to summarize and assess the efficacy and safety of PD-1 inhibitors in patients with RM-NPC who failed platinum-containing chemotherapy. METHODS: Up to August 25, 2022, clinical trials of PD-1 inhibitors in RM-NPC patients who failed platinum-containing regimens were searched in the PubMed, Embase, Cochrane, and Web of Science databases. Retrieval subject terms included "nasopharyngeal carcinoma", "metastatic", "recurrence", "PD-1", and "PD-L1". The clinical trials eligible for inclusion were systematically reviewed and meta-analyzed. RESULTS: A total of 9 studies including 842 patients with RM-NPC were included in this meta-analysis. The results showed that PD-1 inhibitors had promising efficacy in patients with RM-NPC who failed platinum-containing regimens: objective response rate (ORR) was 24% (95% confidence interval [CI] 21-26%), disease control rate (DCR) was 52% (95% CI 45-58%), 1-year progression-free survival (PFS) rate was 25% (95% CI 18-32%), and 1-year overall survival (OS) rate was 53% (95% CI 37-68%). In terms of treatment-related adverse events (AEs), the incidence of grade ≥ 3 treatment-related AEs was 19% (95% CI 13-24%). In addition, we found that PD-1 inhibitors were more effective in patients with PD-L1 positive than in patients with PD-L1 negative nasopharyngeal carcinoma who had failed platinum-containing regimens (ORR 31% (95%CI 26-35%) vs. 21% (95% CI 17-25%)). CONCLUSION: PD-1 inhibitors may provide a survival benefit for patients with RM-NPC who have failed platinum-containing regimens and have the advantage of a good safety profile, making them a promising treatment option.


Assuntos
Inibidores de Checkpoint Imunológico , Neoplasias Nasofaríngeas , Humanos , Carcinoma Nasofaríngeo/tratamento farmacológico , Inibidores de Checkpoint Imunológico/efeitos adversos , Platina/uso terapêutico , Antígeno B7-H1 , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/patologia , Neoplasias Nasofaríngeas/tratamento farmacológico
10.
Anal Chem ; 95(42): 15725-15735, 2023 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-37819747

RESUMO

The trans-cleavage activity of CRISPR/Cas12a has been widely used in biosensing. However, many CRISPR/Cas12a-based biosensors, especially those that work in "on-off-on" mode, usually suffer from high background and thus impossible intracellular application. Herein, this problem is efficiently overcome by elaborately designing the activator strand (AS) of CRISPR/Cas12a using the "RESET" effect found by our group. The activation ability of the as-designed AS to CRISPR/Cas12a can be easily inhibited, thus assuring a low background for subsequent biosensing applications, which not only benefits the detection sensitivity improvement of CRISPR/Cas12a-based biosensors but also promotes their applications in live cells as well as makes it possible to design high-performance biosensors with greatly improved flexibility, thus achieving the analysis of a wide range of targets. As examples, by using different strategies such as strand displacement, strand cleavage, and aptamer-substrate interaction to reactivate the inhibited enzyme activity, several CRISPR/Cas12a-based biosensing systems are developed for the sensitive and specific detection of different targets, including nucleic acid (miR-21), biological small molecules (ATP), and enzymes (hOGG1), giving the detection limits of 0.96 pM, 8.6 µM, and 8.3 × 10-5 U/mL, respectively. Thanks to the low background, these biosensors are demonstrated to work well for the accurate imaging analysis of different biomolecules in live cells. Moreover, we also demonstrate that these sensing systems can be easily combined with lateral flow assay (LFA), thus holding great potential in point-of-care testing, especially in poorly equipped or nonlaboratory environments.


Assuntos
Técnicas Biossensoriais , Ácidos Nucleicos , Sistemas CRISPR-Cas/genética , Bioensaio , Processamento de Imagem Assistida por Computador , Oligonucleotídeos
11.
Chemosphere ; 341: 139998, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37657698

RESUMO

Furan is a widespread endogenous contaminant in heat-processed foods that can accumulate rapidly in the food chain and has been widely detected in foods, such as wheat, bread, coffee, canned meat products, and baby food. Dietary exposure to this chemical may bring health risk. Furan is classified as a possible category 2B human carcinogen by the International Agency for Research on Cancer, with the liver as its primary target organ. Hepatic fibrosis is the most important nontumoral harmful effect of furan and also an important event in the carcinogenesis of furan. Although the specific mechanism of furan-induced liver fibrosis is still unclear, it may involve oxidative stress and genetic toxicity, in which the activation of cytochrome P450 2E1 (CYP2E1) may be the key event. Thus, we conducted a study using an integrating multi-endpoint genotoxicity platform in 120-day in vivo subchronic toxicity test in rats. Results showed that the rats with activated CYP2E1 exhibited DNA double-strand breaks in D4, gene mutations in D60, and increased expression of reactive oxygen species and nuclear factor erythroid 2-related factor 2 in D120. Necrosis, apoptosis, hepatic stellate cell activation, and fibrosis also occurred in the liver, suggesting that furan can independently affect liver fibrosis through oxidative stress and genotoxicity pathways. Point of Departure (PoD) was obtained by benchmark-dose (BMD) method to establish health-based guidance values. The human equivalent dose of PoD derived from BMDL05 was 2.26 µg/kg bw/d. The findings laid a foundation for the safety evaluation and risk assessment of furan and provided data for the further construction and improvement of the adverse outcome pathway network in liver fibrosis.


Assuntos
Rotas de Resultados Adversos , Citocromo P-450 CYP2E1 , Animais , Ratos , Citocromo P-450 CYP2E1/genética , Citocromo P-450 CYP2E1/metabolismo , Furanos/metabolismo , Fígado/metabolismo , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/patologia , Estresse Oxidativo
12.
FEBS Lett ; 597(21): 2643-2655, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37698355

RESUMO

Ovarian fibrosis is a reproduction obstacle leading to female infertility in vertebrates, but the cause underlying the cellular events is unclear. Here, we found that the small adaptor protein SH3-domain-binding glutamate-rich protein like (Sh3bgrl) plays an important role in female reproduction in zebrafish. Two sh3bgrl mutant alleles that result in sh3bgrl depletion contribute to female spawning inability. Comparative transcriptome analysis revealed that sh3bgrl knockout mechanistically causes the upregulation of genes associated with extracellular matrix (ECM) and fiber generation in the zebrafish ovary. Consequently, extra ECM or fibers accumulate and are deposited in the ovary, resulting in eventual spawning inability. Our findings thus provide insights into understanding the underlying mechanism of infertility by ovarian fibrosis and provide a novel and valuable model to study female reproduction abnormality.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Ovário , Peixe-Zebra , Animais , Feminino , Proteínas Adaptadoras de Transdução de Sinal/genética , Fibrose , Peixe-Zebra/genética
13.
Redox Biol ; 64: 102781, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37321060

RESUMO

Diabetic vascular complications can affect both microvascular and macrovascular. Diabetic microvascular complications, such as diabetic nephropathy, diabetic retinopathy, diabetic neuropathy, and diabetic cardiomyopathy, are believed to be caused by oxidative stress. The Nox family of NADPH oxidases is a significant source of reactive oxygen species and plays a crucial role in regulating redox signaling, particularly in response to high glucose and diabetes mellitus. This review aims to provide an overview of the current knowledge about the role of Nox4 and its regulatory mechanisms in diabetic microangiopathies. Especially, the latest novel advances in the upregulation of Nox4 that aggravate various cell types within diabetic kidney disease will be highlighted. Interestingly, this review also presents the mechanisms by which Nox4 regulates diabetic microangiopathy from novel perspectives such as epigenetics. Besides, we emphasize Nox4 as a therapeutic target for treating microvascular complications of diabetes and summarize drugs, inhibitors, and dietary components targeting Nox4 as important therapeutic measures in preventing and treating diabetic microangiopathy. Additionally, this review also sums up the evidence related to Nox4 and diabetic macroangiopathy.


Assuntos
Diabetes Mellitus , Angiopatias Diabéticas , Nefropatias Diabéticas , Humanos , NADPH Oxidase 4/genética , NADPH Oxidase 4/metabolismo , NADPH Oxidases/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Estresse Oxidativo , Nefropatias Diabéticas/etiologia , Nefropatias Diabéticas/genética , Angiopatias Diabéticas/etiologia , Angiopatias Diabéticas/genética , Diabetes Mellitus/tratamento farmacológico , Diabetes Mellitus/genética
14.
Anal Bioanal Chem ; 415(19): 4779-4793, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37354227

RESUMO

N-Glycosylation plays an important role in the structure and function of membrane and secreted proteins. Viral proteins used in cell entry are often extensively glycosylated to assist in protein folding, provide stability, and shield the virus from immune recognition by its host (described as a "glycan shield"). The SARS-CoV-2 spike protein (S) is a prime example, having 22 potential sites of N-glycosylation per protein protomer, as predicted from the primary sequence. In this report, we conducted mass spectrometric analysis of the N-glycosylation profiles of recombinant spike proteins derived from four common SARS-CoV-2 variants classified as Variant of Concern, including Alpha, Beta, Gamma, and Delta along with D614G variant spike as a control. Our data reveal that the amino acid substitutions and deletions between variants impact the abundance and type of glycans on glycosylation sites of the spike protein. Some of the N-glycosylation sequons in S show differences between SARS-CoV-2 variants in the distribution of glycan forms. In comparison with our previously reported site-specific glycan analysis on the S-D614G and its ancestral protein, glycan types on later variants showed high similarity on the site-specific glycan content to S-D614G. Additionally, we applied multiple digestion methods on each sample, and confirmed the results for individual glycosylation sites from different experiment conditions to improve the identification and quantification of glycopeptides. Detailed site-specific glycan analysis of a wide variety of SARS-CoV-2 variants provides useful information toward the understanding of the role of protein glycosylation on viral protein structure and function and development of effective vaccines and therapeutics.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , SARS-CoV-2/metabolismo , Glicosilação , Glicoproteína da Espícula de Coronavírus/química , Polissacarídeos/química
15.
Cell Tissue Res ; 393(2): 281-296, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37256363

RESUMO

The intestine of zebrafish consists of mucosa, muscularis and serosa. Intestinal epithelial cells (IECs) act as a physical and biochemical barrier to protect against invasion by external commensal bacteria. Cell junction is one of the crucial basis of the barrier function. When cell junctions were disrupted, intestinal permeability would be naturally impeded. Extracellular signal-regulated kinase 5 (ERK5), belonging to the Mitogen-activated protein kinase (MAPK) family, is involved in the normal physiological development of the cardiovascular system and nervous system. But the role of erk5 in intestinal morphogenesis and intestinal function is yet to know. Here, we showed that knockout of the erk5 in zebrafish larvae resulted in intestinal wall hypoplasia, including the thinned intestinal wall, reduced intestinal folds, and disrupted cell junctions. In addition, the intestinal permeability assay demonstrated that knockout of erk5 resulted in increased intestinal permeability. All of these showed that erk5 plays an essential role in the maintenance of intestinal barrier function. Thus, our data indicate that erk5 is a critical effector in intestinal morphogenesis and intestinal function, and dysfunction of erk5 would lead to intestinal diseases.


Assuntos
Proteína Quinase 7 Ativada por Mitógeno , Peixe-Zebra , Animais , Peixe-Zebra/metabolismo , Intestinos , Células Epiteliais/metabolismo , Permeabilidade , Mucosa Intestinal/metabolismo
16.
Sci Rep ; 13(1): 6043, 2023 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-37055537

RESUMO

BeiDou Satellite-based Augmentation System (BDSBAS) has come into the trial operation stage since July, 2020. To evaluate the characteristic of the augmentation message in BDSBAS-B1C signal, the effectiveness of the message content was firstly analyzed, and then the validity of the broadcasting strategy was estimated. Finally, the accuracy of the user equivalent ranging error (UERE) and the single frequency positioning error with different correction parameters in BDSBAS-B1C message was evaluated. Based on the above analysis, the effectiveness of the augmentation message was preliminarily verified with the results showing that: (1) the BDSBAS-B1C message type, information content and update interval have basically met the international standard; (2) the accuracy of the UERE obtained with the augmentation message had an obvious improvement in contrast to that of the UERE obtained with the usual navigation message of the GPS satellites, and the ionospheric delay was one of the important factors which affected the accuracy of the UERE; (3) the positioning accuracy obtained with the augmentation message was also improved, and the improvement was more obvious in the service areas with high availability of the ionospheric parameters.

17.
Sheng Li Xue Bao ; 75(2): 197-204, 2023 Apr 25.
Artigo em Chinês | MEDLINE | ID: mdl-37089094

RESUMO

The purpose of this study was to establish a suitable method for extracting cerebrospinal fluid (CSF) from C57BL/6 mice. A patch clamp electrode puller was used to draw a glass micropipette, and a brain stereotaxic device was used to fix the mouse's head at an angle of 135° from the body. Under a stereoscopic microscope, the skin and muscle tissue on the back of the mouse's head were separated, and the dura mater at the cerebellomedullary cistern was exposed. The glass micropipette (with an angle of 20° to 30° from the dura mater) was used to puncture at a point 1 mm inboard of Y-shaped dorsal vertebral artery for CSF sampling. After the first extraction, the glass micropipette was connected with a 1 mL sterile syringe to form a negative pressure device for the second extraction. The results showed that the successful rate of CSF extraction was 83.33% (30/36). Average CSF extraction amount was (7.16 ± 0.43) µL per mouse. In addition, C57BL/6 mice were given intranasally ferric ammonium citrate (FAC) to establish a model of brain iron accumulation, and the CSF extraction technique established in the present study was used for sampling. The results showed that iron content in the CSF from the normal saline control group was not detected, while the iron content in the CSF from FAC-treated group was (76.24 ± 38.53) µmol/L, and the difference was significant. These results suggest that glass micropipette vacuum technique of CSF sampling established in the present study has the advantages of simplicity, high success rate, large extraction volume, and low bleeding rate, and is suitable for the research on C57BL/6 mouse neurological disease models.


Assuntos
Encéfalo , Cisterna Magna , Camundongos , Animais , Vácuo , Camundongos Endogâmicos C57BL , Líquido Cefalorraquidiano
18.
Sci Rep ; 13(1): 4521, 2023 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-36941336

RESUMO

This study aimed to investigate Hippo pathway-related prognostic long noncoding RNAs (lncRNAs) and their prognostic value in liver hepatocellular carcinoma (LIHC). Expression and clinical data regarding LIHC were acquired from The Cancer Genome Atlas and European Bioinformatics Institute array databases. Hippo pathway-related lncRNAs and their prognostic value were revealed, followed by molecular subtype investigations. Differences in survival, clinical characteristics, immune cell infiltration, and checkpoint expression between the subtypes were explored. LASSO regression was used to determine the most valuable prognostic lncRNAs, followed by the establishment of a prognostic model. Survival and differential expression analyses were conducted between two groups (high- and low-risk). A total of 313 Hippo pathway-related lncRNAs were identified from LIHC, of which 88 were associated with prognosis, and two molecular subtypes were identified based on their expression patterns. These two subtypes showed significant differences in overall survival, pathological stage and grade, vascular invasion, infiltration abundance of seven immune cells, and expression of several checkpoints, such as CTLA-4 and PD-1/L1 (P < 0.05). LASSO regression identified the six most valuable independent prognostic lncRNAs for establishing a prognosis risk model. Risk scores calculated by the risk model assigned patients into two risk groups with an AUC of 0.913 and 0.731, respectively, indicating that the high-risk group had poor survival. The risk score had an independent prognostic value with an HR of 2.198. In total, 3007 genes were dysregulated between the two risk groups, and the expression of most genes was elevated in the high-risk group, involving the cell cycle and pathways in cancers. Hippo pathway-related lncRNAs could stratify patients for personalized treatment and predict the prognosis of patients with LIHC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , RNA Longo não Codificante , Humanos , Carcinoma Hepatocelular/genética , Via de Sinalização Hippo , Neoplasias Hepáticas/genética , Prognóstico , RNA Longo não Codificante/genética
19.
J Hazard Mater ; 448: 130821, 2023 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-36709736

RESUMO

Lignin, the most abundant source of renewable aromatic compounds derived from natural lignocellulosic biomass, has great potential for various applications as green materials due to its abundant active groups. However, it is still challenging to quickly construct green polymers with a certain crystallinity by utilizing lignin as a building block. Herein, new green lignin-based covalent organic polymers (LIGOPD-COPs) were one-pot fabricated with water as the reaction solvent and natural lignin as the raw material. Furthermore, by using paraformaldehyde as a protector and modulator, the LIGOPD-COPs prepared under optimized conditions displayed better crystallinity than reported lignin-based polymers, demonstrating the feasibility of preparing lignin-based polymers with improved crystallinity. The improved crystallinity confers LIGOPD-COPs with enhanced application performance, which was demonstrated by their excellent performances in sample treatment of non-targeted food safety analysis. Under optimized conditions, phytochromes, the main interfering matrices, were almost completely removed from different phytochromes-rich vegetables by LIGOPD-COPs, accompanied by "full recovery" of 90 chemical hazards. Green, low-cost, and reusable properties, together with improved crystallinity, will accelerate the industrialization and marketization of lignin-based COPs, and promote their applications in many fields.


Assuntos
Lignina , Polímeros , Lignina/química , Polímeros/química , Biomassa , Água , Solventes
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