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1.
Chem Rev ; 124(8): 4778-4821, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38563799

RESUMO

The shortage of resources such as lithium and cobalt has promoted the development of novel battery systems with low cost, abundance, high performance, and efficient environmental adaptability. Due to the abundance and low cost of sodium, sodium-ion battery chemistry has drawn worldwide attention in energy storage systems. It is widely considered that wide-temperature tolerance sodium-ion batteries (WT-SIBs) can be rapidly developed due to their unique electrochemical and chemical properties. However, WT-SIBs, especially for their electrode materials and electrolyte systems, still face various challenges in harsh-temperature conditions. In this review, we focus on the achievements, failure mechanisms, fundamental chemistry, and scientific challenges of WT-SIBs. The insights of their design principles, current research, and safety issues are presented. Moreover, the possible future research directions on the battery materials for WT-SIBs are deeply discussed. Progress toward a comprehensive understanding of the emerging chemistry for WT-SIBs comprehensively discussed in this review will accelerate the practical applications of wide-temperature tolerance rechargeable batteries.

2.
Cell Mol Life Sci ; 81(1): 118, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38448737

RESUMO

Tektins are microtubule inner proteins (MIPs) and localize at the inside lumen of doublet microtubules (DMTs) of cilia/flagella. TEKTIP1, a newly identified protein by cryo-electron microscopy (cryo-EM), is proposed to be localized at the center of the tektin bundle and hypothesized to recruit tektins or stabilize the bundle. However, the physiological role of TEKTIP1 is unknown. In this study, we generated Tektip1-knockout (Tektip1-/-) mice and showed that they were male subfertile primarily due to reduced sperm motility. A high percentage of sperm from Tektip1-/- mice showed moderately disorganized axoneme structures and abnormal flagellar waveforms. TEKTIP1 predominately interacted with TEKT3 among tektins. Loss of TEKTIP1 partially disturbed the organization of tektin bundle by mainly affecting the native status of TEKT3 and its interaction with other tektins. Collectively, our study reveals the physiological role and potential molecular mechanism of TEKTIP1 in axonemal structure and sperm motility, highlights the importance of MIPs in stabilizing DMTs, and suggests a potential relevance of TEKTIP1 deficiency to human asthenospermia. Tektip1-/- mice will be an excellent animal model to study the DMT organization of sperm flagella using cryo-EM in future.


Assuntos
Axonema , Proteínas dos Microtúbulos , Sêmen , Humanos , Masculino , Animais , Camundongos , Feminino , Microscopia Crioeletrônica , Motilidade dos Espermatozoides , Espermatozoides , Flagelos
3.
Eur J Neurosci ; 59(10): 2535-2548, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38720367

RESUMO

The maturation of forebrain dopamine circuitry occurs over multiple developmental periods, extending from early postnatal life until adulthood, with the precise timing of maturation defined by the target region. We recently demonstrated in the adult mouse brain that axon terminals arising from midbrain dopamine neurons innervate the anterior corpus callosum and that oligodendrocyte lineage cells in this white matter tract express dopamine receptor transcripts. Whether corpus callosal dopamine circuitry undergoes maturational changes between early adolescence and adulthood is unknown but may be relevant to understanding the dramatic micro- and macro-anatomical changes that occur in the corpus callosum of multiple species during early adolescence, including in the degree of myelination. Using quantitative neuroanatomy, we show that dopamine innervation in the forceps minor, but not the rostral genu, of the corpus callosum, is greater during early adolescence (P21) compared to adulthood (>P90) in wild-type mice. We further demonstrate with RNAscope that, as in the adult, Drd1 and Drd2 transcripts are expressed at higher levels in oligodendrocyte precursor cells (OPCs) and decline as these cells differentiate into oligodendrocytes. In addition, the number of OPCs that express Drd1 transcripts during early adolescence is double the number of those expressing the transcript during early adulthood. These data further implicate dopamine in axon myelination and myelin regulation. Moreover, because developmental (activity-independent) myelination peaks during early adolescence, with experience-dependent (activity-dependent) myelination greatest during early adulthood, our data suggest that potential roles of dopamine on callosal myelination shift between early adolescence and adulthood, from a developmental role to an experience-dependent role.


Assuntos
Corpo Caloso , Camundongos Endogâmicos C57BL , Receptores de Dopamina D1 , Receptores de Dopamina D2 , Animais , Camundongos , Corpo Caloso/metabolismo , Corpo Caloso/crescimento & desenvolvimento , Receptores de Dopamina D1/metabolismo , Receptores de Dopamina D2/metabolismo , Receptores de Dopamina D2/genética , Masculino , Neurônios Dopaminérgicos/metabolismo , Dopamina/metabolismo , Células Precursoras de Oligodendrócitos/metabolismo , Feminino
4.
Anal Chem ; 96(24): 9961-9968, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38838250

RESUMO

In this study, a novel europium dual-ligand metal-organic gel (Eu-D-MOGs) with high-efficient anodic annihilation electrochemiluminescence (ECL) was synthesized as an ECL emitter to construct a biosensor for ultrasensitive detection of microRNA-221 (miR-221). Impressively, compared to the ECL signal of europium single-ligand metal-organic gels (Eu-S-MOGs), the ECL signal of Eu-D-MOGs was significantly improved since the two organic ligands could jointly replace the H2O and coordinate with Eu3+, which could remarkably reduce the nonradiative vibrational energy transfer caused by the coordination between H2O and Eu3+ with a high coordination demand. In addition, Eu-D-MOGs could be electrochemically oxidized to Eu-D-MOGs•+ at 1.45 V and reduced to Eu-D-MOGs•- at 0.65 V to achieve effective annihilation of ECL, which overcame the side reaction brought by the remaining emitters at negative potential. This benefited from the annihilation ECL performance of the central ion Eu3+ caused by its redox in the electrochemical process. Furthermore, the annihilation ECL signal of Eu3+ could be improved by sensitizing Eu3+ via the antenna effect. In addition, combined with the improved rolling circle amplification-assisted strand displacement amplification strategy (RCA-SDA), a sensitive biosensor was constructed for the sensitive detection of miR-221 with a low detection limit of 5.12 aM and could be successfully applied for the detection of miR-221 in the lysate of cancer cells. This strategy offered a unique approach to synthesizing metal-organic gels as ECL emitters without a coreactant for the construction of ECL biosensing platforms in biomarker detection and disease diagnosis.


Assuntos
Técnicas Eletroquímicas , Eletrodos , Európio , Géis , Medições Luminescentes , MicroRNAs , Európio/química , MicroRNAs/análise , Técnicas Eletroquímicas/métodos , Ligantes , Géis/química , Técnicas Biossensoriais/métodos , Limite de Detecção , Humanos
5.
Opt Lett ; 49(11): 3226-3229, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38824369

RESUMO

We propose and demonstrate a data fragment multipath transmission scheme to achieve a secure optical communication based on polarization regulation. A dual-polarization Mach-Zehnder modulator (DPMZM) is driven by digital signals which are scattered by field-programmable gate array (FPGA) and transmitted in multiple paths. By utilizing two orthogonal polarization states, we have achieved a signal transmission under different optical parameters, and the transmission rate of the two paths can reach over 10 Gbps through a 20 km fiber with 2.5 Gbps hopping rate. In addition, we establish a theoretical model to analyze the security of the system and simulate brute force cracking; the probability of cracking the minimum information unit is 1.53 × 10-53. This proves that it is difficult to obtain a user data even using the fastest computers. Our scheme has provided, to our knowledge, a new approach for physical layer security.

6.
Brain Behav Immun ; 119: 36-50, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38555991

RESUMO

This study aimed to elucidate the opioid mechanisms underlying dexamethasone-induced pain antihypersensitive effects in neuropathic rats. Dexamethasone (subcutaneous and intrathecal) and membrane-impermeable Dex-BSA (intrathecal) administration dose-dependently inhibited mechanical allodynia and thermal hyperalgesia in neuropathic rats. Dexamethasone and Dex-BSA treatments increased expression of dynorphin A in the spinal cords and primary cultured microglia. Dexamethasone specifically enhanced dynorphin A expression in microglia but not astrocytes or neurons. Intrathecal injection of the microglial metabolic inhibitor minocycline blocked dexamethasone-stimulated spinal dynorphin A expression; intrathecal minocycline, the glucocorticoid receptor antagonist Dex-21-mesylate, dynorphin A antiserum, and κ-opioid receptor antagonist GNTI completely blocked dexamethasone-induced mechanical antiallodynia and thermal antihyperalgesia. Additionally, dexamethasone elevated spinal intracellular cAMP levels, leading to enhanced phosphorylation of PKA, p38 MAPK and CREB. The specific adenylate cyclase inhibitor DDA, PKA inhibitor H89, p38 MAPK inhibitor SB203580 and CREB inhibitor KG-501 completely blocked dexamethasone-induced anti-neuropathic pain and increased microglial dynorphin A exprression. In conclusion, this study reveal that dexamethasone mitigateds neuropathic pain through upregulation of dynorphin A in spinal microglia, likely involving the membrane glucocorticoid receptor/cAMP/PKA/p38 MAPK/CREB signaling pathway.


Assuntos
Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico , Proteínas Quinases Dependentes de AMP Cíclico , AMP Cíclico , Dexametasona , Dinorfinas , Microglia , Neuralgia , Ratos Sprague-Dawley , Transdução de Sinais , Medula Espinal , Proteínas Quinases p38 Ativadas por Mitógeno , Animais , Microglia/metabolismo , Microglia/efeitos dos fármacos , AMP Cíclico/metabolismo , Medula Espinal/metabolismo , Medula Espinal/efeitos dos fármacos , Masculino , Neuralgia/metabolismo , Neuralgia/tratamento farmacológico , Dinorfinas/metabolismo , Ratos , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Dexametasona/farmacologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Hiperalgesia/metabolismo , Hiperalgesia/tratamento farmacológico
7.
Pediatr Res ; 95(4): 1088-1094, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37990079

RESUMO

BACKGROUND: To analyze the clinical characteristics and outcomes of children with severe neurological symptoms associated with the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection during the Omicron pandemic in China. METHODS: This study used a questionnaire to obtain data from pediatric intensive care unit (PICU) centers in seven tertiary hospitals in Northeast China from December 1, 2022, to January 31, 2023. RESULTS: A total of 255 patients were confirmed to have SARS-CoV-2 infection, and 45 patients (17.65 %) were included in this study. Of these, seven (15.6%) patients died, and the median time from admission to death was 35 h (IQR, 14-120 h). Twenty (52.6%) survivors experienced neurological sequelae. Patients with platelet counts lower than 100 × 109/L had a higher incidence of complications such as multiple organ dysfunction, mechanical ventilation rate, and mortality. Cranial magnetic resonance imaging (MRI) always reveals cerebral tissue edema, with some severe lesions forming a softening site. CONCLUSION: Children infected with SARS-CoV-2 often exhibit severe neurological symptoms, and in some cases, they may rapidly develop malignant cerebral edema or herniation, leading to a fatal outcome. An early decrease in platelet count may associated with an unfavorable prognosis. IMPACT: Since early December 2022, China has gradually adjusted its prevention and control policy of SARS-CoV-2; Omicron outbreaks have occurred in some areas for a relatively short period. Due to the differences in ethnicity, endemic strains and vaccination status, there was a little difference from what has been reported about children with SARS-CoV-2 infection with severe neurological symptoms in abroad. This is the first multicenter clinical study in children with nervous system involvement after acute SARS-CoV-2 infection in China, and helpful for pediatricians to have a more comprehensive understanding of the clinical symptoms and prognosis of such disease.


Assuntos
Edema Encefálico , COVID-19 , Criança , Humanos , SARS-CoV-2 , Pandemias , China/epidemiologia , Estudos Retrospectivos
8.
J Org Chem ; 89(4): 2582-2587, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38284164

RESUMO

A catalytic asymmetric vinylogous Mannich-type reaction between ß,γ-unsaturated amides and ketimines has been developed in excellent regio-, diastereo-, and enantioselectivities. The methodology provides an efficient approach to construct chiral homoallylic amines with a 3-amino-2-oxindole scaffold. Moreover, the transformations of the chiral products, including the removal of the pyrazole group or Boc group, the reduction of the C-C double bond, and Suzuki coupling, have been investigated.

9.
J Org Chem ; 89(9): 6180-6192, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38632865

RESUMO

The photochemistry of noncovalent interactions to promote organic transformations is an emerging approach to providing fresh opportunities in synthetic chemistry. Generally, the external substance is necessary to add as an interaction partner, thereby sacrificing the atom economy of the reaction. Herein, we describe a catalyst-free and noncovalent interaction-mediated strategy to access the olefination of N-tosylhydrazones using acetone as a solvent and an interaction partner. This protocol also features broad substrate scope, excellent functional group compatibility, and mild reaction conditions without transition metals. Moreover, the gram-scale synthesis of olefins and the generation of pharmaceutical intermediates highlighted its practical applicability. Lastly, mechanistic studies indicate that the reaction was initiated via noncovalent interactions between acetone and N-tosylhydrazone anion, which is also supported by density functional theory calculations.

10.
J Nat Prod ; 87(2): 228-237, 2024 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-38266493

RESUMO

As a model liverwort, Marchantia polymorpha contains various flavone glucuronides with cardiovascular-promoting effects and anti-inflammatory properties. However, the related glucuronosyltransferases have not yet been reported. In this study, two bifunctional UDP-glucuronic acid/UDP-glucose:flavonoid glucuronosyltransferases/glucosyltransferases, MpUGT742A1 and MpUGT736B1, were identified from M. polymorpha. Extensive enzymatic assays found that MpUGT742A1 and MpUGT736B1 exhibited efficient glucuronidation activity for flavones, flavonols, and flavanones and showed promiscuous regioselectivity at positions 3, 6, 7, 3', and 4'. These enzymes catalyzed the production of a variety of flavonoid glucuronides with medicinal value, including apigenin-7-O-glucuronide and scutellarein-7-O-glucuronide. With the use of MpUGT736B1, apigenin-4'-O-glucuronide and apigenin-7,4'-di-O-glucuronide were prepared by scaled-up enzymatic catalysis and structurally identified by NMR spectroscopy. MpUGT742A1 also displayed glucosyltransferase activity on the 7-OH position of the flavanones using UDP-glucose as the sugar donor. Furthermore, we constructed four recombinant strains by combining the pathway for increasing the UDP-glucuronic acid supply with the two novel UGTs MpUGT742A1 and MpUGT736B1. When apigenin was used as a substrate, the extracellular apigenin-4'-O-glucuronide and apigenin-7,4'-di-O-glucuronide production obtained from the Escherichia coli strain BB2 reached 598 and 81 mg/L, respectively. Our study provides new candidate genes and strategies for the biosynthesis of flavonoid glucuronides.


Assuntos
Flavanonas , Marchantia , Flavonoides/química , Apigenina , Glucuronídeos/metabolismo , Marchantia/metabolismo , Glucuronosiltransferase/química , Glucuronosiltransferase/metabolismo , Escherichia coli/metabolismo , Glucose , Ácido Glucurônico , Difosfato de Uridina
11.
Nature ; 553(7686): 63-67, 2018 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-29300012

RESUMO

Two-dimensional heterojunctions of transition-metal dichalcogenides have great potential for application in low-power, high-performance and flexible electro-optical devices, such as tunnelling transistors, light-emitting diodes, photodetectors and photovoltaic cells. Although complex heterostructures have been fabricated via the van der Waals stacking of different two-dimensional materials, the in situ fabrication of high-quality lateral heterostructures with multiple junctions remains a challenge. Transition-metal-dichalcogenide lateral heterostructures have been synthesized via single-step, two-step or multi-step growth processes. However, these methods lack the flexibility to control, in situ, the growth of individual domains. In situ synthesis of multi-junction lateral heterostructures does not require multiple exchanges of sources or reactors, a limitation in previous approaches as it exposes the edges to ambient contamination, compromises the homogeneity of domain size in periodic structures, and results in long processing times. Here we report a one-pot synthetic approach, using a single heterogeneous solid source, for the continuous fabrication of lateral multi-junction heterostructures consisting of monolayers of transition-metal dichalcogenides. The sequential formation of heterojunctions is achieved solely by changing the composition of the reactive gas environment in the presence of water vapour. This enables selective control of the water-induced oxidation and volatilization of each transition-metal precursor, as well as its nucleation on the substrate, leading to sequential edge-epitaxy of distinct transition-metal dichalcogenides. Photoluminescence maps confirm the sequential spatial modulation of the bandgap, and atomic-resolution images reveal defect-free lateral connectivity between the different transition-metal-dichalcogenide domains within a single crystal structure. Electrical transport measurements revealed diode-like responses across the junctions. Our new approach offers greater flexibility and control than previous methods for continuous growth of transition-metal-dichalcogenide-based multi-junction lateral heterostructures. These findings could be extended to other families of two-dimensional materials, and establish a foundation for the development of complex and atomically thin in-plane superlattices, devices and integrated circuits.

12.
Immun Ageing ; 21(1): 10, 2024 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-38279177

RESUMO

BACKGROUND: Age-related changes in the ovarian microenvironment are linked to impaired fertility in women. Macrophages play important roles in ovarian tissue homeostasis and immune surveillance. However, the impact of aging on ovarian macrophage function and ovarian homeostasis remains poorly understood. METHODS: Senescence-associated beta-galactosidase staining, immunohistochemistry, and TUNEL staining were used to assess senescence and apoptosis, respectively. Flow cytometry was employed to evaluate mitochondrial membrane potential (MMP) and apoptosis in granulosa cells lines (KGN), and macrophages phagocytosis. After a 2-month treatment with low molecular weight Chitosan (LMWC), ovarian tissues from mice were collected for comprehensive analysis. RESULTS: Compared with the liver and uterus, the ovary displayed accelerated aging in an age-dependent manner, which was accompanied by elevated levels of inflammatory factors and apoptotic cells, and impaired macrophage phagocytic activity. The aged KGN cells exhibited elevated reactive oxygen species (ROS) and apoptotic levels alongside decreased MMP. H2O2-induced aging macrophages showed reduced phagocytosis function. Moreover, there were excessive aging macrophages with impaired phagocytosis in the follicular fluid of patients with diminished ovarian reserve (DOR). Notably, LMWC administration alleviated ovarian aging by enhancing macrophage phagocytosis and promoting tissue homeostasis. CONCLUSIONS: Aging ovarian is characterized by an accumulation of aging and apoptotic granulosa cells, an inflammatory response and macrophage phagocytosis dysfunction. In turn, impaired phagocytosis of macrophage contributes to insufficient clearance of aging and apoptotic granulosa cells and the increased risk of DOR. Additionally, LMWC emerges as a potential therapeutic strategy for age-related ovarian dysfunction.

13.
J Appl Toxicol ; 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38639436

RESUMO

Intracerebral hemorrhage (ICH), for which there are currently no effective preventive or treatment methods, has a very high fatality rate. Statins, such as atorvastatin (ATV), are the first-line drugs for regulating blood lipids and treating hyperlipidemia-related cardiovascular diseases. However, ATV-associated ICH has been reported, although its incidence is rare. In this study, we aimed to investigate the protective action and mechanisms of berberine (BBR) against ATV-induced brain hemorrhage. We established an ICH model in zebrafish induced by ATV (2 µM) and demonstrated the effects of BBR (10, 50, and 100 µM) on ICH via protecting the vascular network using hemocyte staining and three transgenic zebrafish. BBR was found to reduce brain inflammation and locomotion injury in ICH-zebrafish. Mechanism research showed that ATV increased the levels of VE-cadherin and occludin proteins but disturbed their localization at the cell membrane by abnormal phosphorylation, which decreased the number of intercellular junctions between vascular endothelial cells (VECs), disrupting the integrity of vascular walls. BBR reversed the effects of ATV by promoting autophagic degradation of phosphorylated VE-cadherin and occludin in ATV-induced VECs examined by co-immunoprecipitation (co-IP). These findings provide crucial insights into understanding the BBR mechanisms involved in the maintenance of vascular integrity and in mitigating adverse reactions to ATV.

14.
Biomed Chromatogr ; 38(8): e5943, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38890009

RESUMO

In this study, a targeted nanocarrier was developed by functionalizing graphene oxide with polyethyleneimine and folic acid, intended for loading oridonin. The nanocarrier was successfully synthesized and characterized using an ultraviolet spectrum, Fourier transform infrared spectroscopy and scanning electron microscopy. The nanocarrier demonstrated a remarkable oridonin loading capacity, reaching 424.8 µg/mg, as determined by ultra-high performance liquid chromatography. In vitro drug release experiments exhibited a pH-dependent release profile, with a higher cumulative release in an acidic environment. The release mechanism followed the Ritger-Peppas equation model. Cytotoxicity assays indicated minimal toxicity of the nanocarrier. Enhanced cellular uptake by MCF7 cells was observed for carriers functionalized with folate and polyethyleneimine. These findings highlight the potential of functionalized graphene oxide as a promising carrier for oridonin delivery in biomedical applications.


Assuntos
Neoplasias da Mama , Diterpenos do Tipo Caurano , Portadores de Fármacos , Grafite , Grafite/química , Diterpenos do Tipo Caurano/química , Diterpenos do Tipo Caurano/farmacologia , Humanos , Células MCF-7 , Portadores de Fármacos/química , Neoplasias da Mama/tratamento farmacológico , Feminino , Antineoplásicos/farmacologia , Antineoplásicos/química , Liberação Controlada de Fármacos , Sobrevivência Celular/efeitos dos fármacos , Ácido Fólico/química , Nanopartículas/química , Cromatografia Líquida de Alta Pressão/métodos
15.
Nano Lett ; 23(20): 9579-9586, 2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37818868

RESUMO

Insertion of metal layers between layered transition-metal dichalcogenides (TMDs) enables the design of new pseudo-2D nanomaterials. The general premise is that various metal atoms may adopt energetically favorable intercalation sites between two TMD sheets. These covalently bound metals arrange in metastable configurations and thus enable the controlled synthesis of nanomaterials in a bottom-up approach. Here, this method is demonstrated by the insertion of Cr or Mn between VSe2 layers. Vacuum-deposited transition metals diffuse between VSe2 layers with increasing concentration, arranging in ordered phases. The Cr3+ or Mn2+ ions are in octahedral coordination and thus in a high-spin state. Measured and computed magnetic moments are high for dilute Cr atoms, but with increasing Cr concentration the average magnetic moment decreases, suggesting antiferromagnetic ordering between Cr ions. The many possible combinations of transition metals with TMDs form a library for exploring quantum phenomena in these nanomaterials.

16.
Zhongguo Dang Dai Er Ke Za Zhi ; 26(6): 605-610, 2024 Jun 15.
Artigo em Zh | MEDLINE | ID: mdl-38926377

RESUMO

OBJECTIVES: To investigate the expression of microRNA-142 (miR-142) in children with autoimmune thyroid disease (AITD) and its relationship with the imbalance of helper T cell 17 (Th17) and regulatory T cell (Treg). METHODS: A total of 89 children hospitalized for AITD from January 2019 to December 2022 were prospectively selected as the study subjects, including 48 children with Graves' disease (GD group) and 41 children with Hashimoto's thyroiditis (HT group). Additionally, 55 healthy children undergoing physical examinations during the same period were selected as the control group. The differences in serum miR-142, antithyroglobulin antibody (TGAb), antithyroperoxidase antibody (TPOAb), Th17/Treg, and interleukin-17 (IL-17) expression were compared among the groups. RESULTS: The expression of miR-142, TPOAb, TGAb, Th17, Th17/Treg, and IL-17 in the GD group and HT group was higher than that in the control group, while Treg was lower than that in the control group (P<0.05). Pearson correlation analysis revealed that in the GD group, miR-142 was positively correlated with TPOAb, TGAb, Th17, Th17/Treg, and IL-17 (r=0.711, 0.728, 0.785, 0.716, 0.709, respectively; P<0.001) and negatively correlated with Treg (r=-0.725, P<0.001); in the HT group, miR-142 was positively correlated with TPOAb and TGAb (r=0.752, 0.717, respectively; P<0.001). CONCLUSIONS: miR-142 is highly expressed in children with AITD, and its expression may be related to the Th17/Treg imbalance in children with GD.


Assuntos
Interleucina-17 , MicroRNAs , Linfócitos T Reguladores , Células Th17 , Humanos , MicroRNAs/sangue , Células Th17/imunologia , Criança , Masculino , Feminino , Linfócitos T Reguladores/imunologia , Interleucina-17/sangue , Doença de Hashimoto/imunologia , Doença de Hashimoto/genética , Doença de Hashimoto/sangue , Pré-Escolar , Doença de Graves/imunologia , Doença de Graves/genética , Adolescente , Autoanticorpos/sangue
17.
J Virol ; 96(13): e0038322, 2022 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-35699445

RESUMO

Despite the rapid deployment of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines, the emergence of SARS-CoV-2 variants and reports of their immune evasion characteristics have led to an urgent need for novel vaccines that confer potent cross-protective immunity. In this study, we constructed three different SARS-CoV-2 spike S1-conjugated nanoparticle vaccine candidates that exhibited high structural homogeneity and stability. Notably, these vaccines elicited up to 50-times-higher neutralizing antibody titers than the S1 monomer in mice. Crucially, it was found that the S1-conjugated nanoparticle vaccine could elicit comparable levels of neutralizing antibodies against wild-type or emerging variant SARS-CoV-2, with cross-reactivity to SARS-CoV and Middle East respiratory syndrome coronavirus (MERS-CoV), the effect of which could be further enhanced using our designed nanoparticles. Our results indicate that the S1-conjugated nanoparticles are promising vaccine candidates with the potential to elicit potent and cross-reactive immunity against not only wild-type SARS-CoV-2, but also its variants of concern, variants of interest, and even other pathogenic betacoronaviruses. IMPORTANCE The emergence of SARS-CoV-2 variants led to an urgent demand for a broadly effective vaccine against the threat of variant infection. The spike protein S1-based nanoparticle designed in our study could elicit a comprehensive humoral response toward different SARS-CoV-2 variants of concern and variants of interest and will be helpful to combat COVID-19 globally.


Assuntos
Formação de Anticorpos , Vacinas contra COVID-19 , COVID-19 , Nanopartículas , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Formação de Anticorpos/imunologia , COVID-19/prevenção & controle , Vacinas contra COVID-19/imunologia , Humanos , Camundongos , SARS-CoV-2/genética , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia
18.
New Phytol ; 237(2): 515-531, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36062450

RESUMO

Unlike bibenzyls derived from the vascular plants, lunularic acid (LA), a key precursor for macrocyclic bisbibenzyl synthesis in nonvascular liverworts, exhibits the absence of one hydroxy group within the A ring. It was hypothesized that both polyketide reductase (PKR) and stilbenecarboxylate synthase 1 (STCS1) were involved in the LA biosynthesis, but the underlined mechanisms have not been clarified. This study used bioinformatics analysis with molecular, biochemical and physiological approaches to characterize STCS1s and PKRs involved in the biosynthesis of LA. The results indicated that MpSTCS1s from Marchantia polymorpha catalyzed both C2→C7 aldol-type and C6→C1 Claisen-type cyclization using dihydro-p-coumaroyl-coenzyme A (CoA) and malonyl-CoA as substrates to yield a C6-C2-C6 skeleton of dihydro-resveratrol following decarboxylation and the C6-C3-C6 type of phloretin in vitro. The protein-protein interaction of PKRs with STCS1 (PPI-PS) was revealed and proved essential for LA accumulation when transiently co-expressed in Nicotiana benthamiana. Moreover, replacement of the active domain of STCS1 with an 18-amino-acid fragment from the chalcone synthase led to the PPI-PS greatly decreasing and diminishing the formation of LA. The replacement also increased the chalcone formation in STCS1s. Our results highlight a previously unrecognized PPI in planta that is indispensable for the formation of LA.


Assuntos
Marchantia , Salicilatos , Coenzima A/química
19.
Reproduction ; 165(5): 543-555, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-36809184

RESUMO

In brief: Hypoxia is vital for the establishment of the maternal-fetal interface during early pregnancy. This study shows that decidual macrophages (dMφ) could be recruited and reside in decidua under the regulation of hypoxia/VEGFA-CCL2 axis. Abstract: Infiltration and residence of decidual macrophages (dMφ) are of great significance to pregnancy maintenance for their role in angiogenesis, placental development, and inducing immune tolerance. Besides, hypoxia has now been acknowledged as an important biological event at maternal-fetal interface in the first trimester. However, whether and how hypoxia regulates biofunctions of dMφ remain elusive. Herein, we observed increased expression of C-C motif chemokine ligand 2 (CCL2) and residence of macrophages in decidua compared to secretory-phase endometrium. Moreover, hypoxia treatment on stromal cells improved the migration and adhesion of dMφ. Mechanistically, these effects might be mediated by upregulated CCL2 and adhesion molecules (especially ICAM2 and ICAM5) on stromal cells in the presence of endogenous vascular endothelial growth factor-A (VEGFA) in hypoxia. These findings were also verified by recombinant VEGFA and indirect coculture, indicating that the interaction between stromal cells and dMφ in hypoxia condition may facilitate dMφ recruitment and residence. In conclusion, VEGFA derived from a hypoxic environment may manipulate CCL2/CCR2 and adhesion molecules to enhance the interactions between dMφ and stromal cells and thus contribute to the enrichment of macrophages in decidua early during normal pregnancy.


Assuntos
Decídua , Placenta , Gravidez , Feminino , Humanos , Placenta/metabolismo , Decídua/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Quimiotaxia , Ligantes , Macrófagos/metabolismo , Quimiocinas/metabolismo , Quimiocina CCL2/metabolismo
20.
J Nutr ; 153(7): 1903-1914, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37269906

RESUMO

BACKGROUND: Hepatic cholesterol accumulation is a significant risk factor in the progression of nonalcoholic fatty liver disease (NAFLD) to steatohepatitis. However, the precise mechanism by which stigmasterol (STG) mitigates this process remains unclear. OBJECTIVES: This study aimed to investigate the potential mechanism underlying the protective effect of STG in mice with NAFLD progressing to steatohepatitis while being fed a high-fat and high-cholesterol (HFHC) diet. METHODS: Male C57BL/6 mice were fed an HFHC diet for 16 wk to establish the NAFLD model. Subsequently, the mice received STG or a vehicle via oral gavage while continuing the HFHC diet for an additional 10 wk. The study evaluated hepatic lipid deposition and inflammation as well as the expression of key rate-limiting enzymes involved in the bile acid (BA) synthesis pathways. BAs in the colonic contents were quantified using ultra-performance liquid chromatography-tandem mass spectrometry. RESULTS: Compared with the vehicle control group, STG significantly reduced hepatic cholesterol accumulation (P < 0.01) and suppressed the gene expression of NLRP3 inflammasome and interleukin-18 (P < 0.05) in the livers of HFHC diet-fed mice. The total fecal BA content in the STG group was nearly double that of the vehicle control group. Additionally, the administration of STG increased the concentrations of representative hydrophilic BAs in the colonic contents (P < 0.05) along with the upregulation of gene and protein expression of CYP7B1 (P < 0.01). Furthermore, STG enhanced the α-diversity of the gut microbiota and partially reversed the alterations in the relative abundance of the gut microbiota induced by the HFHC diet. CONCLUSIONS: STG mitigates steatohepatitis by enhancing the alternative pathway for BA synthesis.


Assuntos
Hipercolesterolemia , Hepatopatia Gordurosa não Alcoólica , Camundongos , Masculino , Animais , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Hepatopatia Gordurosa não Alcoólica/metabolismo , Estigmasterol/metabolismo , Estigmasterol/farmacologia , Colesterol na Dieta/efeitos adversos , Dieta Hiperlipídica/efeitos adversos , Camundongos Endogâmicos C57BL , Fígado/metabolismo , Colesterol/metabolismo , Hipercolesterolemia/complicações , Ácidos e Sais Biliares/metabolismo
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