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1.
PLoS Pathog ; 19(5): e1011123, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37196033

RESUMO

SARS-CoV Spike (S) protein shares considerable homology with SARS-CoV-2 S, especially in the conserved S2 subunit (S2). S protein mediates coronavirus receptor binding and membrane fusion, and the latter activity can greatly influence coronavirus infection. We observed that SARS-CoV S is less effective in inducing membrane fusion compared with SARS-CoV-2 S. We identify that S813T mutation is sufficient in S2 interfering with the cleavage of SARS-CoV-2 S by TMPRSS2, reducing spike fusogenicity and pseudoparticle entry. Conversely, the mutation of T813S in SARS-CoV S increased fusion ability and viral replication. Our data suggested that residue 813 in the S was critical for the proteolytic activation, and the change from threonine to serine at 813 position might be an evolutionary feature adopted by SARS-2-related viruses. This finding deepened the understanding of Spike fusogenicity and could provide a new perspective for exploring Sarbecovirus' evolution.


Assuntos
COVID-19 , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave , Humanos , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/genética , SARS-CoV-2/genética , SARS-CoV-2/metabolismo , Proteólise , Replicação Viral , Glicoproteína da Espícula de Coronavírus/metabolismo , Internalização do Vírus , Serina Endopeptidases/genética , Serina Endopeptidases/metabolismo
2.
Int J Mol Sci ; 25(12)2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38928007

RESUMO

Three types of starch with different amylose content were esterified and blended with polybutylene succinate (PBS) to obtain esterified manioc starch/PBS (EMS/PBS), esterified corn starch/PBS (ECS/PBS), and esterified waxy corn starch/PBS (EWS/PBS) composites. The EMS/PBS and ECS/PBS composites with high amylose content displayed typical V-type crystal structures. The original crystals of EWS, which had low amylose content, were disrupted during the esterification process. EWS exhibited the strongest interaction with PBS and the most favorable interface compatibility. The pyrolysis temperature was in order of EMS/PBS < ECS/PBS < EWS/PBS. The elongation at break of the three blends was higher than that of pure PBS. The esterification and plasticization of the EWS/PBS composite were the most comprehensive. The EWS/PBS composite showed the lowest storage modulus (G') and complex viscosity (η*). The interfacial bonding force of the composite materials increased with more amylopectin, decreasing intermolecular forces and destroying crystal structures, which decreased G' and η* and increased toughness. The EWS/PBS composite, with the least amylose content, had the best hydrophobicity and degradation performance.


Assuntos
Amilose , Amilose/química , Esterificação , Amido/química , Polímeros/química , Viscosidade , Polienos/química , Zea mays/química , Butileno Glicóis/química
3.
Opt Express ; 30(21): 38239-38255, 2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-36258396

RESUMO

Oxygen vacancies (VO), acting as electron traps, have a significant impact on the persistent luminescence (PersL) property of persistent phosphors. However, the effect of VO on PersL remains still unclear enough to limit the development of PersL materials. In this study, the VO concentration of the Y2.978Ce0.018Yb0.004Al2Ga3O12 phosphor is accurately controlled by annealing in air and 10%H2/90%Ar atmospheres at various temperatures. The results show as the annealing temperature increases during the air annealing the VO concentration, the PersL durations, and the thermoluminescence (TL) intensity constantly decreases, and the three data coincide well with each other, indicating the PersL property of the Y2.978Ce0.018Yb0.004Al2Ga3O12 is successfully tuned. Besides, the trap structure of the Y2.978Ce0.018Yb0.004Al2Ga3O12 and the charge compensation effect of Yb ions on VO defects are also discussed. By deconvoluting the TL curves, the Yb trap with a depth of 0.58 eV has been distinctly separated from the VO traps with a quasi-continuous and broad distribution of depths ranging from 0.58 to 1.21 eV. Our work demonstrates a better understanding of the relationship between VO and PersL is of great significance to design a high-performance phosphor.

4.
Opt Express ; 30(10): 16509-16517, 2022 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-36221492

RESUMO

The very long wavelength infrared (VLWIR, >14 µm) spectral band is an indispensable part of new-generation infrared remote sensing. Mercury cadmium telluride (HgCdTe or MCT) has shown excellent potential across the entire infrared band. However, the dark current, which is extremely sensitive to the technological level and small Cd composition, severely limits the performance of VLWIR HgCdTe photodiodes. In this study, cut-off wavelengths of up to 15 µm for HgCdTe devices with novel P-G-I (including wide bandgap p-type cap layer, grading layer and intrinsic absorption layer) designs have been reported. Compared with a device with a double-layer heterojunction (DLHJ) structure, the designed P-G-I structure successfully reduced dark current by suppressing the Shockley-Read-Hall process. Considering the balance of quantum efficiency and dark current, with the introduction of an approximately 0.8 µm thickness Cd composition grading layer, the device can achieve a high detectivity of up to 2.5×1011 cm Hz1/2 W-1. Experiments show that the P-G-I-T device has a lower dark current and a better SRH process suppressing ability than DLHJ devices, the measured detectivity achieved 8.7×1010 cm Hz1/2 W-1. According to additional research, the trap-assisted tunneling current is the primary component of the dark current. Controlling the trap concentration to as low as 1×1013 cm-3 will be continuous and meaningful work. The proposed study provides guidance for VLWIR HgCdTe photodetectors.

5.
Inorg Chem ; 60(23): 17797-17809, 2021 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-34806868

RESUMO

The effect of oxygen vacancies (VO) and the atmosphere influence on persistent luminescence (PersL) in Y3Al2Ga3O12 (YAGG):Ce3+,Yb3+ are investigated by heating it in CO2, air, and 10% H2/90% Ar atmospheres. The VO-rich YAGG phosphors with outstanding PersL are successfully obtained by the common contribution of the reducing atmosphere and the incorporated Yb3+ ions, and the concentration of oxygen vacancies in the phosphors is characterized by X-ray photoelectron spectroscopy and electron paramagnetic resonance measurements. Compared to the best sample prepared in neutral CO2, the reduced sample shows an increase of 30% in initial intensity and 100% in duration time, while the oxidized sample decreases drastically and shows a faint and undetectable PersL. The enhancement is mainly caused by the abundant formation of VO, which is achieved by the pairing of VO with Yb2+ ions. The newly created VO by the reducing calcination is inferred to be adjacent to the Yb site and forms a compensation-type defect cluster due to the charge compensation effect. These findings reveal that understanding the effect and formation of VO is of great significance to design a high-performance phosphor.

6.
Arch Virol ; 166(12): 3405-3408, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34559313

RESUMO

Hepatitis E virus (HEV) can infect humans, pigs, and many other animals, but recombination in HEV has rarely been reported. In the present study, phylogenetic and recombination analysis was performed on 557 complete HEV genome sequences from the GenBank database. A potentially significant quadruple recombination event was identified by recombination detection analysis. The recombinant progeny virus, HEV_32_Manchester_301214, was produced by inter-genotype recombination between the major parent HEPAC-44 and the minor parent HE-JA15-1335. HEV_32_Manchester_301214 and HEPAC-44 belong to genotype 3, while HE-JA15-1335 belongs to genotype 1, and these three strains were all isolated from humans. Three breakpoints of the four recombination events occurred in the ORF2 region, while another occurred in the ORF1 region. This quadruple recombination event was confirmed by phylogenetic analysis. The genotype, host, and recombination regions of the three strains were analyzed, and the analysis results provide valuable information for future research on HEV diversity.


Assuntos
Vírus da Hepatite E , Hepatite E , Doenças dos Suínos , Animais , Genótipo , Hepatite E/veterinária , Vírus da Hepatite E/genética , Filogenia , Recombinação Genética , Suínos
7.
BMC Health Serv Res ; 21(1): 267, 2021 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-33757490

RESUMO

BACKGROUND: To implement the "without the need for a second visit" (WNASV) initiative in our hospital by optimizing the outpatient clinic services via an upgraded information system, in order to increase the quality of outpatient medical services and improve patients' satisfaction. METHODS: An Internet-based care delivery approach was developed and applied to improve the delivery of health care services, simplify the treatment process, and reduce patient waiting time. The patient waiting time and consultation time in the outpatient clinics of our hospital during the peak service intervals and the proportions of various payment methods for outpatient services during the period from May 2017 to September 2019 were retrospectively analyzed. Also, the patients' satisfaction with the outpatient process was surveyed. RESULTS: The waiting time for consultation was shortened from 32.25 min to 28.42 min; the consultation time was shortened from 6.52 min to 3.15 min; and the waiting time for payment decreased from 7.40 min to 4.31 min. The proportion of payment via a counter was reduced from 86.80 to 21.79%, the proportion of self-service payment increased from 9.99 to 16.05%, and the proportion of payment during a consultation increased from 3.21 to 61.91%. The scores of the patients' satisfaction with the outpatient services increased from an average of 89.10 points in 2017 to an average of 90.26 points in 2019. CONCLUSION: The continuous improvement of the service process markedly increases the efficiency of the outpatient services, and effectively improves patient's satisfaction with the outpatient process, this initiative thus deserves further application.


Assuntos
Instituições de Assistência Ambulatorial , Satisfação do Paciente , China , Humanos , Ambulatório Hospitalar , Pacientes Ambulatoriais , Estudos Retrospectivos
8.
Medicine (Baltimore) ; 103(37): e39301, 2024 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-39287318

RESUMO

Educational attainment (EA) is often used as a symbol of socioeconomic status and is associated with several diseases. However, uncertainty remains regarding the potential relationship between EA and chronic pain. This study aimed to evaluate the potential causal association between EA and chronic pain. The primary method employed in Mendelian randomization (MR) analysis was inverse-variance weighted method. Additionally, MR-Egger intercept, Cochran Q, and MR-PRESSO statistical analyses were conducted to assess potential pleiotropy and heterogeneity. The MR analysis provided evidence that genetically predicted additional education significantly reduced the risk of chronic pain. Specifically, this genetic factor may reduce multisite chronic pain by 27.6%, and chronic widespread pain by 3.8%. The results of sensitivity analysis indicated the reliability of our causal estimates. Higher levels of EA may provide protection against chronic pain risk. Enhancing education, narrowing social and economic disparities may help alleviate the burden of chronic pain.


Assuntos
Dor Crônica , Escolaridade , Análise da Randomização Mendeliana , Humanos , Dor Crônica/genética , Dor Crônica/epidemiologia , Causalidade
9.
Acta Radiol Open ; 13(9): 20584601241279134, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39224614

RESUMO

Osteosarcomas predominantly manifest in the long bones of the extremities, with rare occurrences in the skull. A case involving of a 53-year-old female who presented to the authors' hospital for examination due to dizziness was incidentally found to have an occipital bone mass, which was initially diagnosed as a benign tumor and did not receive sufficient attention. Two years later, owing to tumor enlargement, the patient underwent further evaluation at the same institution, which revealed evidence of occipital bone destruction. Pathological analysis confirmed the diagnosis of osteosarcoma. The patient underwent surgical resection followed by radiotherapy. Despite its infrequency and uncharacteristic initial presentation, skull osteosarcomas should not be overlooked.

10.
J Colloid Interface Sci ; 672: 311-328, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-38850859

RESUMO

The difficulty of recycling and the finite photocatalytic performance of primitive nano-photocatalysts restrict their application in wastewater purification. In this study, a multifunctional membrane with efficient synergistic adsorption and degradation performance was constructed. The nano-photocatalyst layered bimetallic oxide (LDO) was combined with the matrix membrane polyarylether nitrile (PEN) by delayed phase transition technology. The introduced 2-Methylimidazole (2-MeIm) provided a virtual electron transfer pathway between PEN and LDO and enhanced the photocatalytic performance. The results suggested that PEN/LDO/2-MeIm has outstanding removal performance to organic dyes methylene blue (MB). After three consecutive cycles, the reacted membrane can be readily recovered from the system. The MB removal rate remained high at 89.38%, suggesting that the functional membrane is eligible for recycling and reuse. Finally, based on liquid chromatography-mass spectrometry (LC-MS) analysis and density functional theory (DFT) calculations, the mechanism and pathway of MB photodegradation by the PEN/LDO/2-MeIm system were proposed. Therefore, constructing PEN/LDO/2-MeIm membranes in this study may offer a novel perspective on creating eco-friendly and functional PEN-based membranes for practical use in wastewater purification.

11.
Polymers (Basel) ; 16(16)2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39204516

RESUMO

To reduce production costs and enhance the high-temperature resistance of SiO2 aerogels, an aluminum-doped silica aerogel (ASA) was successfully prepared using the sol-gel method and atmospheric drying method. The composite silica sources included TEOS and inexpensive acidic silica sol, while the aluminum source was aluminum sol. The study investigated the influence of the molar ratio of acidic silica sol to TEOS, Al/Si, and calcination temperature on the composition, structure, and high-temperature resistance of the ASA. The results indicate that a sample with an acidic silica sol to TEOS molar ratio of 0.8 achieved a specific surface area of 683.204 m2·g-1. The Al/Si molar ratio significantly impacted the high-temperature resistance of the ASA, with the sample having a molar ratio of 0.02 Al/Si displaying the highest specific surface area of 705.956 m2·g-1 at 600 °C. Moreover, this surface area remained at 273.099 m2·g-1 after calcination at 1000 °C, notably higher than the sample without aluminum sol (16.082 m2·g-1). Mechanism analysis indicated that the addition of aluminum sol to the SiO2 aerogel inhibited phase transitions, and both acidic silica sol and aluminum sol particles enhanced the aerogel structure, contributing to a marked improvement in high-temperature resistance.

12.
ACS Appl Bio Mater ; 7(2): 1073-1080, 2024 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-38215043

RESUMO

Herein, we reported an innovative thermodynamic allosteric switch-actuated 3D DNA nanomachine for selective, sensitive, and accurate electrochemical (EC)/fluorescent (FL) dual-mode biosensing of a microphthalmia-associated transcription factor (MITF). The thermodynamic allosteric switch was ingeniously customized as a hairpin probe (HP) that was in dynamic equilibrium but rapidly interconverting conformations. At the "inactive state", the MITF-binding region and the switch part were "sequestered". Upon the introduction of MITF, an MITF-HP complex promptly formed, and the equilibrium of HP thermodynamically inclined from the "inactive state" toward the "active state" conformation. Immediately, the exposed switch on HP effectively actuated the 3D DNA nanomachine and synchronously produced the restriction site for Nb.BbvCI nicking endonuclease. After the autonomous conveying of the 3D DNA nanomachine by means of the high-efficiency circularly nicking endonuclease signal amplification (NESA), not only was MB-S1 in the supernatant used for FL measurements but also MB-SP/MNs/S2 in the precipitate was adapted for EC analysis, significantly improving the utilization of output products derived from the 3D DNA nanomachine. Accordingly, benefiting from the efficient DNA nanomachine signal amplification manner and the self-calibration function of a dual-mode bioassay, the constructed biosensor exhibits superior sensitivity and accuracy for MITF determination.


Assuntos
Técnicas Biossensoriais , Fatores de Transcrição , Fatores de Transcrição/genética , DNA/química , Regulação da Expressão Gênica , Endonucleases/genética
13.
Transl Androl Urol ; 13(1): 25-41, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38404552

RESUMO

Background: Irradiation (IR) promotes inflammation and apoptosis by inducing oxidative stress and/or mitochondrial dysfunction (MD). The kidneys are rich in mitochondria, and mitophagy maintains normal renal function by eliminating damaged mitochondria and minimizing oxidative stress. However, whether astragaloside IV (AS-IV) can play a protective role through the mitophagy pathway is not known. Methods: We constructed a radiation injury model using hematoxylin and eosin (HE) staining, blood biochemical analysis, immunohistochemistry, TdT-mediated dUTP nick end labeling (TUNEL) staining, ultrastructural observation, and Western blot analysis to elucidate the AS-IV resistance mechanism for IR-induced renal injury. Results: IR induced mitochondrial damage; the increase of creatinine (SCr), blood urea nitrogen (BUN) and uric acid (UA); and the activation of NOD-like receptor thermal protein domain-associated protein 3 (NLRP3) inflammasome and apoptosis in renal tissue. AS-IV administration attenuated the IR-induced MD and reactive oxygen species (ROS) levels in the kidney; enhanced the levels of mitophagy-associated protein [PTEN-induced putative kinase 1 (PINK1)], parkin proteins, and microtubule-associated protein 1 light 3 (LC3) II/I ratio in renal tissues; diminished NLRP3 inflammasome activation-mediated proteins [cleaved cysteinyl aspartate-specific proteinase-1 (caspase-1), interleukin-1ß (IL-1ß)] and apoptosis-related proteins [cleaved caspase-9, cleaved caspase-3, BCL2-associated X (Bax)]; reduced SCr, BUN, and UA levels; and attenuated the histopathological alterations in renal tissue. Conversely, mitophagy inhibitor cyclosporin A (CsA) suppressed the AS-IV-mediated protection of renal tissue. Conclusions: AS-IV can strongly diminish the activation and apoptosis of NLRP3 inflammasome, thus attenuating the renal injury induced by radiation by promoting the PINK1/parkin-mediated mitophagy. These findings suggest that AS-IV is a promising drug for treating IR-induced kidney injury.

14.
EClinicalMedicine ; 75: 102794, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39281098

RESUMO

Background: Autoimmune diseases are known to be associated with an increased risk of cancer. Whether maternal immune dysregulation can have an impact on the development of haematological malignancies in offspring remains uncertain. Therefore, we explored the association between offspring risk of haematological malignancies and maternal autoimmune disease using a real-world nationwide population-based study. Methods: In this case-control study, we identified 2172 children with haematological malignancies between 2004 and 2019 from Taiwan's National Health Insurance program and compared them with population-based controls without haematologic malignancies, who were matched with each individual at a ratio of 1:4. The medical information of the autoimmune mothers were obtained from the Taiwan Maternal and Child Health Database. Conditional logistic regression was used to estimate the odds ratio for haematologic malignancy in offspring. Furthermore, subgroup and stratified analyses were conducted. Findings: Among the rheumatologic diseases in our study, Crohn's disease was the most common disease both in the haematological malignancy group (1.1%) and the control group (0.9%). In multivariable analysis, the odds ratio for haematological malignancy in offspring with maternal autoimmune diseases was 1.2 (95% confidence interval [CI] 0.91-1.58). The overall risk of haematologic malignancy was not significantly higher when adjusted for specific risk factors, including neonatal age, maternal age, family income, urbanization, maternal occupation, birth weight, or maternal comorbidity, except for prematurity. When comparing different autoimmune diseases among haematological malignancies and the control group, maternal psoriatic arthritis/psoriasis had the highest adjusted overall risk for haematological malignancies (adjusted OR 2.11, CI 0.89-5), followed by ankylosing spondylitis (adjusted OR 1.45, CI 0.7-3), autoimmune thyroiditis (OR 1.26, CI 0.57-2.81), systemic lupus erythematosus (OR 1.21, CI 0.48-3.02), Crohn's disease (OR 1.19, CI 0.75-1.9), and Sjogren's syndrome (OR 1.18, CI 0.65-2.15), but no significance was reached in these analyses. Multivariable analysis of risk factors associated with haematological malignancy subtypes was done. It showed no associations between maternal autoimmune disease and childhood haematological malignancies. Interpretation: We found no significant relationship between maternal autoimmune disease and childhood haematological malignancies. The influence of maternal immune dysregulation on the next generation with respect to haematological malignancies development may be limited. Funding: There was no funding source for this study.

15.
Seizure ; 120: 41-48, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38897163

RESUMO

OBJECTIVE: To analyze cerebellar atrophy in genetic epileptic encephalopathies (EEs). METHODS: This research included a retrospective cohort study conducted from January 2016 to December 2023 and a systematic review on cerebellar atrophy in genetic EEs. Pediatric individuals who were diagnosed with EEs based on electroclinical features, carried causative gene variants, and exhibited cerebellar atrophy were recruited. Electroclinical features, neuroimaging findings, and causative variants of eligible individuals were analyzed. RESULTS: The cohort study showed 10 of 67 pediatric individuals (10/67; 15 %) who were diagnosed with genetic EEs had cerebellar atrophy; and 6 of the 10 individuals (6/10; 60 %) exhibited cerebellar signs. Diagnostic delay between the detection of cerebellar atrophy and the identification of genetic diagnosis existed in 6 individuals (6/10; 60 %) and the median duration was 4.4 years. A total of 32 genes, including 31 genes from the literature review and a newly identified SCN2A gene in this cohort, were reported associated with cerebellar atrophy in genetic EEs. Twenty-six genes (26/32; 81 %) accounted for cerebellar atrophy associated with other brain anomalies and 6 genes (6/32; 19 %) caused isolated cerebellar atrophy. Twenty-five genes (25/32; 78 %) showed late-onset cerebellar atrophy identified after the age of 1 year old. CONCLUSION: Cerebellar atrophy is not uncommon in genetic EEs and may serve as an indicator for molecular diagnosis in clinical practice. To shorten the diagnostic delay, follow-up neuroimaging study is crucial because of high rate of clinico-radiological dissociation and late-onset cerebellar atrophy in this patient group.


Assuntos
Atrofia , Cerebelo , Humanos , Atrofia/patologia , Cerebelo/patologia , Cerebelo/diagnóstico por imagem , Feminino , Masculino , Pré-Escolar , Criança , Lactente , Estudos Retrospectivos , Doenças Cerebelares/genética , Doenças Cerebelares/diagnóstico , Doenças Cerebelares/patologia , Doenças Cerebelares/diagnóstico por imagem , Estudos de Coortes , Epilepsia/genética , Epilepsia/diagnóstico , Adolescente
16.
EBioMedicine ; 109: 105379, 2024 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-39368454

RESUMO

BACKGROUND: The PHILA study suggests that pyrotinib, trastuzumab, and docetaxel significantly improved progression-free survival (PFS) compared with placebo, trastuzumab, and docetaxel in patients with untreated HER2-positive metastatic breast cancer. In this study, we aimed to investigate the synergistic mechanisms of pyrotinib plus trastuzumab and provide further insights for the PHILA trial. METHODS: The in vitro activity of combination treatments was assessed through cell biological and biochemical experiments. The in vivo efficacy was evaluated in cell-derived xenografts, a TUBO tumour model, and one clinical case. Next-generation sequencing was performed on circulating tumour DNA (ctDNA) from patients in the PHILA trial. FINDINGS: The combination of pyrotinib and trastuzumab more effectively inhibited cell growth than pyrotinib or trastuzumab alone in models of HER2-dependent breast cancer. It potentiated membrane HER2 ubiquitination and downregulation, which resulted in a comprehensive blockade of the HER2 signalling pathway. The pyrotinib-altered membrane HER2 levels had no significant effect on trastuzumab-mediated antibody-dependent cell-mediated cytotoxicity (ADCC). We further validated the synergistic mechanisms in TUBO tumours and one clinical case, rather than models of HCC1954 cells harbouring the PIK3CA H1047R mutation. Similarly, in our centre cohort of the PHILA study, patients with genetic alterations in the HER2 signalling cascade had significantly shorter median PFS than individuals with the wild-type pathway. INTERPRETATION: Our findings underscore the robust synergy between pyrotinib and trastuzumab in overcoming HER2 dependency and provide a rationale for pyrotinib, trastuzumab, and docetaxel as one of the optimal choices for patients with untreated HER2-positive metastatic breast cancer, who are dependent on the HER2 signalling cascade. FUNDING: This work was supported by the National Key Research and Development Program of China (2021YFF1201300), the National Natural Science Foundation of China (82172875), the CAMS Innovation Fund for Medical Sciences (CIFMS) (2022-I2M-2-001), and the Joint Innovative Fund of Beijing Natural Science Foundation and Changping District (L234004).

17.
Nat Protoc ; 19(5): 1311-1347, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38307980

RESUMO

As a key glycolytic metabolite, lactate has a central role in diverse physiological and pathological processes. However, comprehensive multiscale analysis of lactate metabolic dynamics in vitro and in vivo has remained an unsolved problem until now owing to the lack of a high-performance tool. We recently developed a series of genetically encoded fluorescent sensors for lactate, named FiLa, which illuminate lactate metabolism in cells, subcellular organelles, animals, and human serum and urine. In this protocol, we first describe the FiLa sensor-based strategies for real-time subcellular bioenergetic flux analysis by profiling the lactate metabolic response to different nutritional and pharmacological conditions, which provides a systematic-level view of cellular metabolic function at the subcellular scale for the first time. We also report detailed procedures for imaging lactate dynamics in live mice through a cell microcapsule system or recombinant adeno-associated virus and for the rapid and simple assay of lactate in human body fluids. This comprehensive multiscale metabolic analysis strategy may also be applied to other metabolite biosensors using various analytic platforms, further expanding its usability. The protocol is suited for users with expertise in biochemistry, molecular biology and cell biology. Typically, the preparation of FiLa-expressing cells or mice takes 2 days to 4 weeks, and live-cell and in vivo imaging can be performed within 1-2 hours. For the FiLa-based assay of body fluids, the whole measuring procedure generally takes ~1 min for one sample in a manual assay or ~3 min for 96 samples in an automatic microplate assay.


Assuntos
Técnicas Biossensoriais , Ácido Láctico , Animais , Humanos , Camundongos , Técnicas Biossensoriais/métodos , Ácido Láctico/metabolismo , Ácido Láctico/análise
18.
Nat Commun ; 15(1): 133, 2024 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-38168040

RESUMO

Adipocytes are the primary sites for fatty acid storage, but the synthesis rate of fatty acids is very low. The physiological significance of this phenomenon remains unclear. Here, we show that surplus fatty acid synthesis in adipocytes induces necroptosis and lipodystrophy. Transcriptional activation of FASN elevates fatty acid synthesis, but decreases NADPH level and increases ROS production, which ultimately leads to adipocyte necroptosis. We identify MED20, a subunit of the Mediator complex, as a negative regulator of FASN transcription. Adipocyte-specific male Med20 knockout mice progressively develop lipodystrophy, which is reversed by scavenging ROS. Further, in a murine model of HIV-associated lipodystrophy and a human patient with acquired lipodystrophy, ROS neutralization significantly improves metabolic disorders, indicating a causal role of ROS in disease onset. Our study well explains the low fatty acid synthesis rate in adipocytes, and sheds light on the management of acquired lipodystrophy.


Assuntos
Adipócitos , Lipodistrofia , Masculino , Camundongos , Humanos , Animais , Espécies Reativas de Oxigênio/metabolismo , Adipócitos/metabolismo , Lipodistrofia/genética , Lipodistrofia/metabolismo , Ácidos Graxos/metabolismo , Estresse Oxidativo , Camundongos Knockout
19.
Signal Transduct Target Ther ; 9(1): 114, 2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38678055

RESUMO

Developing a mucosal vaccine against SARS-CoV-2 is critical for combatting the epidemic. Here, we investigated long-term immune responses and protection against SARS-CoV-2 for the intranasal vaccination of a triple receptor-binding domain (RBD) scaffold protein (3R-NC) adjuvanted with a flagellin protein (KFD) (3R-NC + KFDi.n). In mice, the vaccination elicited RBD-specific broad-neutralizing antibody responses in both serum and mucosal sites sustained at high level over a year. This long-lasting humoral immunity was correlated with the presence of long-lived RBD-specific IgG- and IgA-producing plasma cells, alongside the Th17 and Tfh17-biased T-cell responses driven by the KFD adjuvant. Based upon these preclinical findings, an open labeled clinical trial was conducted in individuals who had been primed with the inactivated SARS-CoV-2 (IAV) vaccine. With a favorable safety profile, the 3R-NC + KFDi.n boost elicited enduring broad-neutralizing IgG in plasma and IgA in salivary secretions. To meet the challenge of frequently emerged variants, we further designed an updated triple-RBD scaffold protein with mutated RBD combinations, which can induce adaptable antibody responses to neutralize the newly emerging variants, including JN.1. Our findings highlight the potential of the KFD-adjuvanted triple-RBD scaffold protein is a promising prototype for the development of a mucosal vaccine against SARS-CoV-2 infection.


Assuntos
Administração Intranasal , Anticorpos Neutralizantes , Anticorpos Antivirais , Vacinas contra COVID-19 , COVID-19 , Flagelina , SARS-CoV-2 , SARS-CoV-2/imunologia , Humanos , Flagelina/imunologia , Flagelina/genética , Flagelina/administração & dosagem , COVID-19/prevenção & controle , COVID-19/imunologia , Animais , Camundongos , Vacinas contra COVID-19/imunologia , Vacinas contra COVID-19/administração & dosagem , Anticorpos Neutralizantes/imunologia , Feminino , Anticorpos Antivirais/imunologia , Vacinação , Masculino , Adulto , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/genética , Imunoglobulina G/imunologia , Imunoglobulina G/sangue , Imunoglobulina A/imunologia , Pessoa de Meia-Idade
20.
NPJ Vaccines ; 9(1): 170, 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-39285168

RESUMO

Developing broad-spectrum influenza vaccines is crucial for influenza control and potential pandemic preparedness. Here, we reported a novel vaccine design utilizing circular RNA (circRNA) as a delivery platform for multi-subtype neuraminidases (NA) (influenza A N1, N2, and influenza B Victoria lineage NA) immunogens. Individual NA circRNA lipid nanoparticles (LNP) elicited robust NA-specific antibody responses with neuraminidase inhibition activity (NAI), preventing the virus from egressing and infecting neighboring cells. Additionally, the administration of circRNA LNP induced cellular immunity in mice. To achieve a universal influenza vaccine, we combined all three subtypes of NA circRNA-LNPs to generate a trivalent circRNA vaccine. The trivalent vaccine elicited a balanced antibody response against all three NA subtypes and a Th1-biased immune response in mice. Moreover, it protected mice against the lethal challenge of matched and mismatched H1N1, H3N2, and influenza B viruses, encompassing circulating and ancestral influenza virus strains. This study highlights the potential of delivering multiple NA antigens through circRNA-LNPs as a promising strategy for effectively developing a universal influenza vaccine against diverse influenza viruses.

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