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1.
Nat Methods ; 20(2): 276-283, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36646897

RESUMO

Cryo-electron tomography (cryo-ET) has become a powerful approach to study the high-resolution structure of cellular macromolecular machines in situ. However, the current correlative cryo-fluorescence and electron microscopy lacks sufficient accuracy and efficiency to precisely prepare cryo-lamellae of target locations for subsequent cryo-ET. Here we describe a precise cryogenic fabrication system, ELI-TriScope, which sets electron (E), light (L) and ion (I) beams at the same focal point to achieve accurate and efficient preparation of a target cryo-lamella. ELI-TriScope uses a commercial dual-beam scanning electron microscope modified to incorporate a cryo-holder-based transfer system and embed an optical imaging system just underneath the vitrified specimen. Cryo-focused ion beam milling can be accurately navigated by monitoring the real-time fluorescence signal of the target molecule. Using ELI-TriScope, we prepared a batch of cryo-lamellae of HeLa cells targeting the centrosome with a success rate of ~91% and discovered new in situ structural features of the human centrosome by cryo-ET.


Assuntos
Tomografia com Microscopia Eletrônica , Elétrons , Humanos , Tomografia com Microscopia Eletrônica/métodos , Microscopia Crioeletrônica/métodos , Células HeLa , Substâncias Macromoleculares
2.
PLoS Biol ; 21(6): e3002142, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37289842

RESUMO

Rab26 is known to regulate multiple membrane trafficking events, but its role in insulin secretion in pancreatic ß cells remains unclear despite it was first identified in the pancreas. In this study, we generated Rab26-/- mice through CRISPR/Cas9 technique. Surprisingly, insulin levels in the blood of the Rab26-/- mice do not decrease upon glucose stimulation but conversely increase. Deficiency of Rab26 promotes insulin secretion, which was independently verified by Rab26 knockdown in pancreatic insulinoma cells. Conversely, overexpression of Rab26 suppresses insulin secretion in both insulinoma cell lines and isolated mouse islets. Islets overexpressing Rab26, upon transplantation, also failed to restore glucose homeostasis in type 1 diabetic mice. Immunofluorescence microscopy revealed that overexpression of Rab26 results in clustering of insulin granules. GST-pulldown experiments reveal that Rab26 interacts with synaptotagmin-1 (Syt1) through directly binding to its C2A domain, which interfering with the interaction between Syt1 and SNAP25, and consequently inhibiting the exocytosis of newcomer insulin granules revealed by TIRF microscopy. Our results suggest that Rab26 serves as a negative regulator of insulin secretion, via suppressing insulin granule fusion with plasma membrane through sequestering Syt1.


Assuntos
Diabetes Mellitus Experimental , Células Secretoras de Insulina , Insulinoma , Ilhotas Pancreáticas , Neoplasias Pancreáticas , Animais , Camundongos , Diabetes Mellitus Experimental/metabolismo , Exocitose/fisiologia , Glucose/metabolismo , Insulina/metabolismo , Secreção de Insulina , Células Secretoras de Insulina/metabolismo , Insulinoma/metabolismo , Ilhotas Pancreáticas/metabolismo , Neoplasias Pancreáticas/metabolismo
3.
Proc Natl Acad Sci U S A ; 120(24): e2304506120, 2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37279276

RESUMO

Dynamic molecular devices operating with time- and history-dependent performance raised new challenges for the fundamental study of microscopic non-steady-state charge transport as well as functionalities that are not achievable by steady-state devices. In this study, we reported a generic dynamic mode of molecular devices by addressing the transient redox state of ubiquitous quinone molecules in the junction by proton/water transfer. The diffusion limited slow proton/water transfer-modulated fast electron transport, leading to a non-steady-state transport process, as manifested by the negative differential resistance, dynamic hysteresis, and memory-like behavior. A quantitative paradigm for the study of the non-steady-state charge transport kinetics was further developed by combining the theoretical model and transient state characterization, and the principle of the dynamic device can be revealed by the numerical simulator. On applying pulse stimulation, the dynamic device emulated the neuron synaptic response with frequency-dependent depression and facilitation, implying a great potential for future nonlinear and brain-inspired devices.

4.
J Biol Chem ; : 107508, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38944116

RESUMO

In the Neurospora circadian system, the White Collar Complex (WCC) formed by WC-1 and WC-2 drives expression of the frequency (frq) gene whose product FRQ feedbacks to inhibit transcriptional activity of WCC. Phosphorylation of WCC has been extensively studied, but the extent and significance of other post-translational modifications (PTM) has been poorly studied. To this end, we used mass-spectrometry to study alkylation sites on WCC, resulting in discovery of nine acetylation sites. Mutagenesis analysis showed most of the acetylation events individually do not play important roles in period determination. Moreover, mutating all the lysines falling in either half of WC-1 or all the lysine residues in WC-2 to arginines did not abolish circadian rhythms. In addition, we also found nine mono-methylation sites on WC-1, but like acetylation, individual ablation of most of the mono-methylation events did not result in a significant period change. Taken together, the data here suggest that acetylation or mono-methylation on WCC is not a determinant of the pace of the circadian feedback loop. The finding is consistent with a model in which repression of WCC's circadian activity is controlled mainly by phosphorylation. Interestingly, light-induced expression of some light-responsive genes has been modulated in certain wc-1 acetylation mutants, suggesting that WC-1 acetylation events differentially regulate light responses.

5.
J Biol Chem ; 300(3): 105779, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38395305

RESUMO

The newly discovered zoonotic coronavirus swine acute diarrhea syndrome coronavirus (SADS-CoV) causes acute diarrhea, vomiting, dehydration, and high mortality rates in newborn piglets. Although SADS-CoV uses different strategies to evade the host's innate immune system, the specific mechanism(s) by which it blocks the interferon (IFN) response remains unidentified. In this study, the potential of SADS-CoV nonstructural proteins (nsp) to inhibit the IFN response was detected. The results determined that nsp1 was a potent antagonist of IFN response. SADS-CoV nsp1 efficiently inhibited signal transducer and activator of transcription 1 (STAT1) phosphorylation by inducing Janus kinase 1 (JAK1) degradation. Subsequent research revealed that nsp1 induced JAK1 polyubiquitination through K11 and K48 linkages, leading to JAK1 degradation via the ubiquitin-proteasome pathway. Furthermore, SADS-CoV nsp1 induced CREB-binding protein degradation to inhibit IFN-stimulated gene production and STAT1 acetylation, thereby inhibiting STAT1 dephosphorylation and blocking STAT1 transport out of the nucleus to receive antiviral signaling. In summary, the results revealed the novel mechanisms by which SADS-CoV nsp1 blocks the JAK-STAT signaling pathway via the ubiquitin-proteasome pathway. This study yielded valuable findings on the specific mechanism of coronavirus nsp1 in inhibiting the JAK-STAT signaling pathway and the strategies of SADS-CoV in evading the host's innate immune system.


Assuntos
Alphacoronavirus , Infecções por Coronavirus , Complexo de Endopeptidases do Proteassoma , Doenças dos Suínos , Proteínas não Estruturais Virais , Animais , Acetilação , Alphacoronavirus/fisiologia , Infecções por Coronavirus/veterinária , Infecções por Coronavirus/virologia , Janus Quinase 1/genética , Janus Quinase 1/metabolismo , Fosforilação , Complexo de Endopeptidases do Proteassoma/metabolismo , Fator de Transcrição STAT1/genética , Fator de Transcrição STAT1/metabolismo , Suínos , Ubiquitinas/metabolismo , Doenças dos Suínos/metabolismo , Doenças dos Suínos/virologia , Células HEK293 , Células Vero , Humanos , Chlorocebus aethiops , Proteínas não Estruturais Virais/metabolismo
6.
Arch Microbiol ; 206(4): 140, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38441642

RESUMO

Limosilactobacillus reuteri is an indigenous inhabitant of the animal gut known for its probiotic effects on the host. In our previous study, a large number of L. reuteri strains were isolated from the gastrointestinal tract of mice recovering from ulcerative colitis, from which we randomly selected L. reuteri RE225 for whole genome sequencing to explore its probiotic properties. The results of next-generation sequencing and third-generation single molecule sequencing showed that L. reuteri RE225 contained many genes encoding functional proteins associated with adhesion, anti-inflammatory and pathogen inhibition. And compared to other L. reuteri strains in NCBI, L. reuteri RE225 has unique gene families with probiotic functions. In order to further explore the probiotic effect of the L. reuteri RE225, the derived peptides were identified by LC-MS/MS, and the peptides with tumor necrosis factor-α binding ability were screened by reverse molecular docking and microscale thermophoresis. Finally, cell experiments demonstrated the anti-inflammatory ability of the peptides. Western blotting and qPCR analyses confirmed that the selected peptides might alleviate LPS-induced inflammation in NCM460 cells by inhibiting JAK2/STAT3 pathway activation.


Assuntos
Colite Ulcerativa , Limosilactobacillus reuteri , Animais , Camundongos , Limosilactobacillus reuteri/genética , Colite Ulcerativa/tratamento farmacológico , Cromatografia Líquida , Simulação de Acoplamento Molecular , Espectrometria de Massas em Tandem , Peptídeos/genética , Peptídeos/farmacologia , Sequenciamento Completo do Genoma
7.
Arch Microbiol ; 206(3): 131, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38421449

RESUMO

A new strain of Bacillus velezensis NDB was isolated from Xiangshan Harbor and antibacterial test revealed antibacterial activity of this strain against 12 major pathogenic bacteria. The whole genome of the bacterium was sequenced and found to consist of a 4,214,838 bp circular chromosome and a 7410 bp circular plasmid. Furthermore, it was predicted by AntiSMASH and BAGEL4 to have 12 clusters of secondary metabolism genes for the synthesis of the inhibitors, fengycin, bacillomycin, macrolactin H, bacillaene, and difficidin, and there were also five clusters encoding potentially novel antimicrobial substances, as well as three bacteriocin biosynthesis gene clusters of amylocyclicin, ComX1, and LCI. qRT-PCR revealed significant up-regulation of antimicrobial secondary metabolite synthesis genes after 24 h of antagonism with pathogenic bacteria. Furthermore, MALDI-TOF mass spectrometry revealed that it can secrete surfactin non-ribosomal peptide synthase and polyketide synthase to exert antibacterial effects. GC-MS was used to analyze methanol extract of B. velezensis NDB, a total of 68 compounds were identified and these metabolites include 16 amino acids, 17 acids, 3 amines, 11 sugars, 11 alcohols, 1 ester, and 9 other compounds which can inhibit pathogenic bacteria by initiating the antibiotic secretion pathway. A comparative genomic analysis of gene families showed that the specificity of B. velezensis NDB was mainly reflected in environmental adaptability. Overall, this research on B. velezensis NDB provides the basis for elucidating its biocontrol effect and promotes its future application as a probiotic.


Assuntos
Bacillus , Bacillus/genética , Antibacterianos/farmacologia , Aminas , Aminoácidos
8.
BMC Med Imaging ; 24(1): 2, 2024 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-38166678

RESUMO

BACKGROUND: In some patients with nonischemic cardiomyopathy (NICM), left ventricular (LV) function improves with medical assistance, resulting in left ventricular reverse remodeling (LVRR). However, predictors of LVRR are not fully understood. The left atrium (LA) has been reported as a prognostic predictor in patients with heart failure (HF). The present study aimed to evaluate clinical predictors of LVRR related to LA function on cardiac magnetic resonance (CMR). METHODS: A total of 103 patients with reduced left ventricular ejection fraction (LVEF) were enrolled in this retrospective study between September 2015 and July 2021. CMR parameters, including strain data, were measured in all patients. Echocardiographic data obtained approximately 2 years after enrollment were analyzed to assess LVRR. RESULTS: LVRR occurred in 46 patients (44.7%) during follow-up. The value of LA conduit strain was higher in the LVRR group than in the non-LVRR group (6.6 [interquartile range (IQR): 5.6-9.3]% versus 5.0 [IQR: 3.0-6.2]%; p < 0.001). The multivariate logistic regression analysis showed that LA conduit strain was an independent predictor of LVRR (odds ratio [OR]: 1.216, 95% confidence interval [CI]: 1.050-1.408; p = 0.009). The area under the receiver operating characteristic (ROC) curve of the LA conduit strain was 0.746, and the cutoff value was 6.2%. The Kaplan‒Meier analysis revealed that the incidence of adverse cardiac events was significantly lower in patients with LA conduit strain > 6.2% compared to those with ⩽6.2%. (log-rank test, p = 0.019). CONCLUSIONS: LA conduit strain derived from CMR is an independent predictor of LVRR in patients with NICM.


Assuntos
Cardiomiopatias , Função Ventricular Esquerda , Humanos , Volume Sistólico , Estudos Retrospectivos , Cardiomiopatias/diagnóstico por imagem , Espectroscopia de Ressonância Magnética , Átrios do Coração/diagnóstico por imagem
9.
Anal Chem ; 95(51): 18880-18888, 2023 12 26.
Artigo em Inglês | MEDLINE | ID: mdl-38088834

RESUMO

Biocompatible fluorescent probes have emerged as essential tools in life sciences for visualizing subcellular structures and detecting specific analytes. Herein, we report the synthesis and characterization of a novel fluorescent probe (TPE-FdU), incorporated with hydrophilic 2'-fluoro-substituted deoxyuridine and hydrophobic ethynyl tetraphenylethene moieties, which possessed typical aggregation-induced emission (AIE) behavior. In comparison to the TPE-FdU (pKa 7.68) treated in neutral conditions, it performed well at pH 4, exhibiting an enhanced 450 nm emission signal of approximately four times stronger. As the pH value was increased to 10, the fluorescence intensity was completely quenched. The TEM images of TPE-FdU in an acidic environment (nanospherical morphology, AIE enhance, pH = 4) and in a basic environment (microrods, fluorescence quenching, pH = 9) revealed that it was a pH-dependent self-assembled probe, which was also illustrated by the interpretation of the NMR spectrum. Furthermore, the TPE-FdU probe exhibited a specific response to trace Hg2+ ions. Interestingly, the quenched fluorescence of the TPE-FdU probe caused by Hg2+ can be recovered by the addition of GSH due to the formation of the Hg-S bond being released away. MTT assay and CLSM images demonstrated that TPE-FdU was nontoxic and selectively visualized in the intracellular mitochondria. These results contributed to the development of advanced fluorescent probes with diverse applications in cell imaging, environment protection, and biomedical research.


Assuntos
Floxuridina , Corantes Fluorescentes , Corantes Fluorescentes/química , Mitocôndrias , Espectrometria de Fluorescência , Concentração de Íons de Hidrogênio
10.
Fungal Genet Biol ; 164: 103763, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36481248

RESUMO

Fungal cells are quite unique among life in their organization and structure, and yet implementation of many tools recently developed for fluorescence imaging in animal systems and yeast has been slow in filamentous fungi. Here we present analysis of properties of fluorescent proteins in Neurospora crassa as well as describing genetic tools for the expression of these proteins that may be useful beyond cell biology applications. The brightness and photostability of ten different fluorescent protein tags were compared in a well-controlled system; six different promoters are described for the assessment of the fluorescent proteins and varying levels of expression, as well as a customizable bidirectional promoter system. We present an array of fluorescent proteins suitable for use across the visible light spectrum to allow for 4-color imaging, in addition to a photoconvertible fluorescent protein that enables a change in the color of a small subset of proteins in the cell. These tools build on the rich history of cell biology research in filamentous fungi and provide new tools to help expand research capabilities.


Assuntos
Neurospora crassa , Animais , Neurospora crassa/genética , Neurospora crassa/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Corantes/metabolismo
11.
Magn Reson Med ; 90(6): 2217-2232, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37496253

RESUMO

PURPOSE: Measuring lipid composition provides more information than just total lipid content. Hence, the non-invasive measurement of unsaturated lipid protons with both high efficiency and precision is of pressing need. This study was to optimize echo time (TE) for the best resolving of J-difference editing of unsaturated lipid resonances. METHODS: The TE dependence of J-difference-edited (JDE) MRS was verified in the density-matrix simulation, soybean oil phantom, in-vivo experiments of white adipose tissue (WAT), and skeletal muscles using single-voxel MEGA-PRESS sequence at 3T. The peak SNRs and Cramér-Rao lower bounds (CRLBs) acquired at the proposed TE of 45 ms and previously published TE of 70 ms were compared (eight pairs) in WAT, extramyocelluar lipids (EMCLs), and intramyocellular lipids (IMCLs). The lipid composition in skeletal muscles was compared between healthy males (n = 7) and females (n = 7). RESULTS: The optimal TE was suggested as 45 ms. Compared to 70 ms, the mean signal gains at TE of 45 ms were 151% in WAT, 168% in EMCL, 204% in IMCL for allylic resonance, and 52% in EMCL for diallylic resonance. CRLBs were significantly reduced at TE of 45 ms in WAT, EMCL, IMCL for allylic resonance and in EMCL for diallylic resonance. With TE of 45 ms, significant gender differences were found in the lipid composition in EMCL pools, while no difference in IMCL pools. CONCLUSION: The JDE-MRS protocol with TE of 45 ms allows improved quantification of unsaturated lipid resonances in vivo and future lipid metabolism investigations.


Assuntos
Músculo Esquelético , Prótons , Masculino , Feminino , Humanos , Espectroscopia de Ressonância Magnética/métodos , Músculo Esquelético/diagnóstico por imagem , Imagens de Fantasmas , Lipídeos
12.
J Magn Reson Imaging ; 57(1): 296-307, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35635494

RESUMO

BACKGROUND: Pancreatic fat accumulation may cause or aggravate the process of acute pancreatitis, ß-cell dysfunction, T2DM disease, and even be associated with pancreatic tumors. The pathophysiology of fatty pancreas remains overlooked and lacks effective imaging diagnostics. PURPOSE: To automatically measure the distribution of pancreatic fat deposition on Dixon MRI in multicenter/population datasets using nnU-Net models. STUDY TYPE: Retrospective. POPULATION: A total of 176 obese/nonobese subjects (90 males, 86 females; mean age, 27.2 ± 19.7) were enrolled, including a training set (N = 132) and a testing set (N = 44). FIELD STRENGTH/SEQUENCE: A 3 T and 1.5 T/gradient echo T1 dual-echo Dixon. ASSESSMENT: The segmentation results of four types of nnU-Net models were compared using dice similarity coefficient (DSC), positive predicted value (PPV), and sensitivity. The ground truth was the manual delineation by two radiologists according to in-phase (IP) and opposed-phase (OP) images. STATISTICAL TESTS: The group difference of segmentation results of four models were assessed by the Kruskal-Wallis H test with Dunn-Bonferroni comparisons. The interobserver agreement of pancreatic fat fraction measurements across three observers and test-retest reliability of human and machine were assessed by intragroup correlation coefficient (ICC). P < 0.05 was considered statistically significant. RESULTS: The three-dimensional (3D) dual-contrast model had significantly improved performance than 2D dual-contrast (DSC/sensitivity) and 3D one-contrast (IP) models (DSC/PPV/sensitivity) and had less errors than 3D one-contrast (OP) model according to higher DSC and PPV (not significant), with a mean DSC of 0.9158, PPV of 0.9105 and sensitivity of 0.9232 in the testing set. The test-retest ICC of this model was above 0.900 in all pancreatic regions, exceeded human. DATA CONCLUSION: 3D Dual-contrast nnU-Net aided segmentation of pancreas on Dixon images appears to be adaptable to multicenter/population datasets. It fully automates the assessment of pancreatic fat distribution and has high reliability. EVIDENCE LEVEL: 3 TECHNICAL EFFICACY: Stage 3.


Assuntos
Pancreatite , Masculino , Feminino , Humanos , Criança , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos Retrospectivos , Doença Aguda , Imageamento por Ressonância Magnética/métodos , Pâncreas/diagnóstico por imagem
13.
FASEB J ; 36(10): e22530, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36063128

RESUMO

Despite the best treatment, approximately 10% of fractures still face undesirable repair and result in delayed unions or non-unions. Dynamic mechanical stimulation promotes bone formation, when applied at the correct time frame, with optimal loading magnitude, frequency, and repetition. Controlled mechanical loading significantly increases osteogenic cells during the matrix deposition phase of bone repair. In the bone defect, the blood vessel network guides the initial bone formation activities. A unique blood vessel subtype (Type H) exists in bone, which expresses high levels of CD31 and endomucin, and functions to couple angiogenesis and osteogenesis. However, how this form of controlled mechanical loading regulates the Type H vessels and promotes bone formation is still not clear. Sphingosine 1-phosphate (S1P) participates in the bone anabolic process and is a key regulator of the blood vessel. Its receptor, sphingosine 1-phosphate receptor 1 (S1Pr1), is a mechanosensitive protein that regulates vascular integrity. Therefore, we hypothesis that controlled anabolic mechanical loading promotes bone repair by acting on Type H vessels. To study the effect of S1Pr1 on loading induced-bone repair, we utilized a stabilized tibial defect model, which allows for the application of anabolic mechanical loading. Mechanical loading upregulated S1Pr1 within the entire defect, with up to 80% expressed in blood vessels, as observed by deep tissue imaging. Additionally, S1Pr1 antagonism by W146 inhibited the anabolic effects of mechanical loading. We showed that mechanical loading or activating S1Pr1 could induce YAP nuclear translocation, a key regulator in the cell's mechanical response, in endothelial cells (ECs) in vitro. Inhibition of S1Pr1 in endothelial cells by siRNA reduced loading-induced YAP nuclear translocation and expressions of angiogenic genes. In vivo, YAP nuclear translocation in Type H vessels was up-regulated after mechanical loading but was inhibited by antagonizing S1Pr1. S1Pr1 agonist, FTY720, increased bone volume and Type H vessel volume, similar to that of mechanical stimulation. In conclusion, controlled anabolic mechanical loading enhanced bone formation mainly through Type H vessels in a S1Pr1-dependent manner.


Assuntos
Células Endoteliais , Receptores de Lisoesfingolipídeo , Regeneração Óssea , Células Endoteliais/metabolismo , Cloridrato de Fingolimode/farmacologia , Receptores de Lisoesfingolipídeo/genética , Receptores de Lisoesfingolipídeo/metabolismo , Receptores de Esfingosina-1-Fosfato
14.
Mol Cell Biochem ; 2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37436653

RESUMO

Inflammatory bone disease is a general term for a series of diseases caused by chronic inflammation, which leads to the destruction of bone homeostasis, that is, the osteolytic activity of osteoclasts increases, and the osteogenic activity of osteoblasts decreases, leading to osteolysis. Macrophages are innate immune cell with plasticity, and their polarization is related to inflammatory bone diseases. The dynamic balance of macrophages between the M1 phenotype and the M2 phenotype affects the occurrence and development of diseases. In recent years, an increasing number of studies have shown that extracellular vesicles existing in the extracellular environment can act on macrophages, affecting the progress of inflammatory diseases. This process is realized by influencing the physiological activity or functional activity of macrophages, inducing macrophages to secrete cytokines, and playing an anti-inflammatory or pro-inflammatory role. In addition, by modifying and editing extracellular vesicles, the potential of targeting macrophages can be used to provide new ideas for developing new drug carriers for inflammatory bone diseases.

15.
Biomacromolecules ; 24(1): 109-117, 2023 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-36461924

RESUMO

Three-dimensional (3D) printable hydrogels with a shape memory effect have emerged as a new class of 4D printing materials recently and found wide applications in various fields. However, synergistically endowing such materials with good mechanical strength and biocompatibility for biomedical uses remains challenging. In this study, a series of multiresponsive hydrogels have been prepared through a dynamic covalent imine/Diels-Alder network from biocompatible starting materials of modified gelatin and poly(ethylene glycol)-based polymers. By further secondary crosslinking with a hyperbranched triethoxysilane reagent (HPASi) that contains multiple supramolecular hydrogen bonding, the hydrogels presented a strengthened self-healing and temperature-responsive shape memory effect. With the additional features of superior stretchability (elongation at break up to 523%), good cytocompatibility, and 3D printable properties, these multifunctional hydrogels showed great potential for broad biomedical applications.


Assuntos
Gelatina , Hidrogéis , Materiais Biocompatíveis/farmacologia , Hidrogéis/farmacologia , Polímeros , Impressão
16.
Nanotechnology ; 34(14)2023 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-36260977

RESUMO

All-inorganic cesium lead halide CsPbX3(X = Cl, Br, I) perovskite quantum dots (PQDs) have shown promising potential in current Mini/Micro-LED display applications due to their excellent photoluminescence performance. However, lead ions in PQDs are easily to leak owing to the unstable structure of PQDs, which hinders their commercial applications. Herein, we adopt Rb+ions co-doping strategy to regulate the doping characteristics of Mn2+ions in CsPbCl3PQDs. The synthesized CsPbCl3:(Rb+, Mn2+) PQDs possess enhanced photoluminescence quantum yield of 71.1% due to the reduction of intrinsic defect states and Mn-Mn or Mn-traps in co-doped PQDs. Moreover, the white light emission of CsPb(Cl/Br)3:(Rb+, Mn2+) PQDs is achieved by anion exchange reaction and the constructed WLED exhibits the CIE coordinate of (0.33, 0.29) and the correlated color temperature of 5497 K. Benefiting from the substitution strategy, these doped CsPbX3PQDs can be widely used as fluorescence conversion materials for the construction of Mini/Micro-LED.

17.
BMC Cardiovasc Disord ; 23(1): 492, 2023 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-37794360

RESUMO

BACKGROUND: Fibrosis-5 (FIB-5) index is a marker of liver fibrosis and has been shown to have a good prognostic value for patients with acute heart failure (AHF), and C-reactive protein (CRP) has inflammatory properties and predicts adverse prognosis in patients with HF. However, the long-term prognostic value of FIB-5 index combined with CRP in patients with acute decompensated HF (ADHF) is yet unclear. METHODS: This retrospective study included 1153 patients with ADHF hospitalized from January 2018 to May 2022.The FIB-5 index was calculated as (albumin [g/L]×0.3 + PLT count [109/L]×0.05)-(ALP [U/L]×0.014 + AST to ALT ratio×6 + 14). Patients were stratified into the following four groups according to the median value of FIB-5 index (=-2.11) and CRP (= 4.5): Group 1 had a high FIB-5 index (FIB-5 index >-2.11) and a low CRP (CRP ≤ 4.5); Group 2 had both low FIB-5 index and low CRP; Group 3 had both high FIB-5 index and high CRP; Group 4 had a low FIB-5 index (FIB-5 index ≤-2.11) and a high CRP (CRP > 4.5). The endpoint was major adverse cardiac and cerebral events (MACCEs). Multivariate Cox analysis was used to evaluate the association of the combination with the development of MACCEs. Net reclassification improvement (NRI) and integrated discrimination improvement (IDI) analysis were used to compare the accuracy of the combination with a single prognostic factor for predicting the risk of MACCEs. RESULTS: During the mean follow-up period of 584 ± 12 days, 488 (42.3%) patients had MACCEs. Kaplan-Meier analysis revealed that the incidence of MACCEs was different in the four groups (P < 0.001). After adjusting for the confounding factors, the hazard ratio (HR) for MACCEs in Group 4 (low FIB-5 index + high CRP) was the highest (Model 1, HR = 2.04, 95%CI 1.58-2.65, P < 0.001; Model 2, HR = 1.67, 95%CI 1.28-2.18, P < 0.001; Model 3, HR = 1.66, 95%CI: 1.27-2.17, P < 0.001). Additionally, the combination of FIB-5 index and CRP enabled more accurate prediction of MACCEs than FIB-5 index alone (NRI, 0.314,95%CI 0.199-0.429; P < 0.001; IDI, 0.023; 95% CI 0.015-0.032; P < 0.001). CONCLUSIONS: In patients with ADHF, the combination of the FIB-5 index and CRP may be useful in risk stratification in the future.


Assuntos
Proteína C-Reativa , Insuficiência Cardíaca , Humanos , Prognóstico , Proteína C-Reativa/metabolismo , Estudos Retrospectivos , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/metabolismo , Fibrose
18.
Mol Ther ; 30(6): 2342-2353, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35192934

RESUMO

Type 2 diabetes mellitus (DM2) is associated closely with non-alcoholic fatty liver disease (NAFLD) by affecting lipid metabolism, which may lead to non-alcoholic steatohepatitis (NASH), fibrosis, and hepatocellular carcinoma (HCC). N6-methyladenosine (m6A) RNA methylation is an important epigenetic regulation for gene expression and is related to HCC development. We developed a new NAFLD model oriented from DM2 mouse, which spontaneously progressed to histological features of NASH, fibrosis, and HCC with high incidence. By RNA sequencing, protein expression and methylated RNA immunoprecipitation (MeRIP)-qPCR analysis, we found that enhanced expression of ACLY and SCD1 in this NAFLD model and human HCC samples was due to excessive m6A modification, but not elevation of mature SREBP1. Moreover, targeting METTL3/14 in vitro increases protein level of ACLY and SCD1 as well as triglyceride and cholesterol production and accumulation of lipid droplets. m6A sequencing analysis revealed that overexpressed METTL14 binds to mRNA of ACLY and SCD1 and alters their expression pattern. Our findings demonstrate a new NAFLD mouse model that provides a study platform for DM2-related NAFLD and reveals a unique epitranscriptional regulating mechanism for lipid metabolism via m6A-modified protein expression of ACLY and SCD1.


Assuntos
Carcinoma Hepatocelular , Diabetes Mellitus Tipo 2 , Neoplasias Hepáticas , Hepatopatia Gordurosa não Alcoólica , Animais , Carcinoma Hepatocelular/patologia , Diabetes Mellitus Tipo 2/genética , Epigênese Genética , Fibrose , Lipogênese/genética , Neoplasias Hepáticas/metabolismo , Camundongos , Hepatopatia Gordurosa não Alcoólica/metabolismo , RNA Mensageiro/genética
19.
Skin Pharmacol Physiol ; 36(3): 160-164, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36917958

RESUMO

Autism is a neurodevelopmental disorder. Individuals with autism can exhibit multiple neurological symptoms such as deficit in social communication, restricted interests, and repetitive behaviors. Recent study showed that murine model of autism displays an increased transepidermal water loss (TEWL) and dry skin. But whether epidermal functions are also altered in children with autism is unknown. In the present study, TEWL, stratum corneum hydration, and skin surface pH were compared between children with autism (N = 56) and normal controls (N = 48). Our results showed that children with autism exhibited lower stratum corneum hydration levels, higher TEWL, and elevated skin surface pH in comparison to normal controls (p < 0.0001 for all). These results demonstrate that children with autism exhibit epidermal dysfunction.


Assuntos
Transtorno Autístico , Humanos , Criança , Animais , Camundongos , Transtorno Autístico/metabolismo , Epiderme/metabolismo , Água/metabolismo , Perda Insensível de Água , Pele
20.
Molecules ; 28(24)2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38138606

RESUMO

(1) Background: Ginsenoside Rb1-PLGA nanoparticles (GRb1@PLGA@NPs) represent a novel nanotherapeutic system, yet their therapeutic efficacy and underlying mechanisms for treating heart failure (HF) remain unexplored. This study aims to investigate the potential mechanisms underlying the therapeutic effects of GRb1@PLGA@NPs in HF treatment; (2) Methods: The left anterior descending coronary artery ligation was employed to establish a HF model in Sprague-Dawley rats, along with an in vitro oxidative stress model using H9c2 myocardial cells. Following treatment with GRb1@PLGA@NPs, cardiac tissue pathological changes and cell proliferation were observed. Additionally, the serum levels of biomarkers such as NT-proBNP, TNF-α, and IL-1ß were measured, along with the expression of the ROS/PPARα/PGC1α pathway; (3) Results: GRb1@PLGA@NPs effectively ameliorated the pathological status of cardiac tissues in HF rats, mitigated oxidative stress-induced myocardial cell damage, elevated SOD and MMP levels, and reduced LDH, MDA, ROS, NT-proBNP, TNF-α, and IL-1ß levels. Furthermore, the expression of PPARα and PGC1α proteins was upregulated; (4) Conclusions: GRb1@PLGA@NPs may attenuate myocardial cell injury and treat HF through the ROS/PPARα/PGC1α pathway.


Assuntos
Insuficiência Cardíaca , PPAR alfa , Ratos , Animais , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo , Fator de Necrose Tumoral alfa , Insuficiência Cardíaca/tratamento farmacológico
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