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1.
Opt Express ; 32(11): 20218-20229, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38859137

RESUMO

Traditional camera-based single-molecule localization microscopy (SMLM), with its high imaging resolution and localization throughput, has made significant advancements in biological and chemical researches. However, due to the limitation of the fluorescence signal-to-noise ratio (SNR) of a single molecule, its resolution is difficult to reach to 5 nm. Optical lattice produces a nondiffracting beam pattern that holds the potential to enhance microscope performance through its high contrast and penetration depth. Here, we propose a new method named LatticeFLUX which utilizes the wide-field optical lattice pattern illumination for individual molecule excitation and localization. We calculated the Cramér-Rao lower bound of LatticeFLUX resolution and proved that our method can improve the single molecule localization precision by 2.4 times compared with the traditional SMLM. We propose a scheme using 9-frame localization, which solves the problem of uneven lattice light illumination. Based on the experimental single-molecule fluorescence SNR, we coded the image reconstruction software to further verify the resolution enhancement capability of LatticeFLUX on simulated punctate DNA origami, line pairs, and cytoskeleton. LatticeFLUX confirms the feasibility of using 2D structured light illumination to obtain high single-molecule localization precision under high localization throughput. It paves the way for further implementation of ultra-high resolution full 3D structured-light-illuminated SMLM.

2.
Chemistry ; 30(17): e202303580, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38179818

RESUMO

Hydrogen-bonded organic frameworks (HOFs) are a class of crystalline framework materials assembled by hydrogen bonds. HOFs have the advantages of high crystallinity, mild reaction conditions, good solution processability, and reproducibility. Coupled with the reversibility and flexibility of hydrogen bonds, HOFs can be assembled into a wide diversity of crystalline structures. Since the bonding energy of hydrogen bonds is lower than that of ligand and covalent bonds, the framework of HOFs is prone to collapse after desolventisation and the stability is not high, which limits the development and application of HOFs. In recent years, numerous stable and functional HOFs have been developed by π-π stacking, highly interpenetrated networks, charge-assisted, ligand-bond-assisted, molecular weaving, and covalent cross-linking. Charge-assisted ionic HOFs introduce electrostatic attraction into HOFs to improve stability while enriching structural diversity and functionality. In this paper, we review the development, the principles of rational design and assembly of charge-assisted ionic HOFs, and introduces the different building block construction modes of charge-assisted ionic HOFs. Highlight the applications of charge-assisted ionic HOFs in gas adsorption and separation, proton conduction, biological applications, etc., and prospects for the diverse design of charge-assisted ionic HOFs structures and multifunctional applications.

3.
Chemistry ; 29(26): e202300028, 2023 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-36807423

RESUMO

Two ionic hydrogen-bonded organic frameworks (iHOF-10, iHOF-11) were prepared using 1,1'-diamino-4,4'-bipyridine diiodide (Dbpy ⋅ 2I) and tetrakis(4-sulfophenyl)ethylene (H4 TPE). With increasing RH and temperature, water molecules induce single crystal to single crystal (SCSC) transformation of iHOF-10, resulting in the formation of iHOF-11. At 90 °C, 98 % RH, the proton conductivity of iHOF-11 (7.03×10-3  S cm-1 ) is 2.09 times higher than iHOF-10 (3.37×10-3  S cm-1 ). At 50 °C, 98 % RH, iHOF-11 (9.49×10-4  S cm-1 ) is 19.06 times higher than iHOF-10 (4.98×10-5  S cm-1 ). The proton conductivity shows water molecules enter the crystal and induce crystal transformation and reorganization of the hydrogen bonding structure, thus increasing the proton conductivity and stability.

4.
J Basic Microbiol ; 63(2): 179-189, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36515292

RESUMO

Bacillus subtilis, as a biocontrol bacterium, possess a variety of biological functions and the capacity to control plant pathogens. Iturin A is a biosurfactant with broad-spectrum antifungal activity produced by fermentation of B. subtilis. In this study, the dynamic parameters of solid-state fermentation (SSF) and submerged fermentation (SMF) of Bacillus velezensis ND were compared, and a method for producing iturin A with a yield of 12.46 g/kg utilizing SSF was proposed. It has significant advantages over SMF and has the highest yield of all previously reported studies. B. velezensis ND also contains protease activity, cellulase activity, iron-carrying activity, the ability to synthesis 3-indoleacetic acid (IAA), fixation nitrogen, and degrade phosphorus. In cotton pot experiments, it can effectively increase cotton growth and minimize Verticillium wilt. This strain's superior fermentation efficiency, biological function, and biocontrol ability are sufficient to demonstrate its promise for the development and use of biocontrol agents.


Assuntos
Bacillus , Agentes de Controle Biológico , Bacillus/metabolismo , Bacillus subtilis/metabolismo , Agentes de Controle Biológico/farmacologia , Agentes de Controle Biológico/metabolismo , Peptídeos Cíclicos
5.
Int J Mol Sci ; 24(3)2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36768228

RESUMO

Cold stress is one of the major abiotic stresses limiting tea production. The planting of cold-resistant tea cultivars is one of the most effective measures to prevent chilling injury. However, the differences in cold resistance between tea cultivars remain unclear. In the present study, we perform a transcriptomic and metabolomic profiling of Camellia sinensis var. "Shuchazao" (cold-tolerant, SCZ) and C. sinensis var. assamica "Yinghong 9" (cold-sensitive, YH9) during cold acclimation and analyze the correlation between gene expression and metabolite biosynthesis. Our results show that there were 51 differentially accumulated metabolites only up-regulated in SCZ in cold-acclimation (CA) and de-acclimation (DA) stages, of which amino acids accounted for 18%. The accumulation of L-arginine and lysine in SCZ in the CA stage was higher than that in YH9. A comparative transcriptomic analysis showed an enrichment of the amino acid biosynthesis pathway in SCZ in the CA stage, especially "arginine biosynthesis" pathways. In combining transcriptomic and metabolomic analyses, it was found that genes and metabolites associated with amino acid biosynthesis were significantly enriched in the CA stage of SCZ compared to CA stage of YH9. Under cold stress, arginine may improve the cold resistance of tea plants by activating the polyamine synthesis pathway and CBF (C-repeat-binding factor)-COR (cold-regulated genes) regulation pathway. Our results show that amino acid biosynthesis may play a positive regulatory role in the cold resistance of tea plants and assist in understanding the cold resistance mechanism differences among tea varieties.


Assuntos
Camellia sinensis , Transcriptoma , Perfilação da Expressão Gênica , Camellia sinensis/metabolismo , Chá/genética , Chá/metabolismo , Aminoácidos/metabolismo , Arginina/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
6.
World J Microbiol Biotechnol ; 37(6): 100, 2021 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-33983497

RESUMO

Methylobacterium sp. CLZ was isolated from soil contaminated with chemical wastewater. This strain simultaneously synthesizes Pyrroloquinoline quinone (PQQ), Coenzyme Q10 (CoQ10), and carotenoids by utilizing methanol as a carbon source. Comparative genomic analysis was performed for five Methylobacterium strains. As per the outcomes, the Methylobacterium CLZ strain showed the smallest genome size and the lowest number of proteins. Thus, it can serve as an ideal cell model for investigating the biological process of Methylobacterium and constructing genetically engineered Methylobacterium. The Methylobacterium CLZ strain's pqqL gene, which does not occur in other Methylobacterium strains but plays a crucial role in PQQ synthesis. This was a surprising finding for the study of PQQ biosynthesis in Methylobacterium. Methylobacterium sp. NI91 strain was generated by random mutagenesis of CLZ strain, and NI91 strain showed a 72.44% increase in PQQ yield. The mutation in the mxaJ gene involved in the methanol dehydrogenase (MDH) synthesis was identified through comparative genomic analysis of the whole genome of mutant strain NI91 and wild-type strain CLZ. The mxaJ gene was found to be upregulated in the NI91 strain. Thus, the up-regulation of the mxaJ gene could be correlated with the high yield of PQQ, and it could provide valuable clues for strain engineering to improve PQQ production.


Assuntos
Proteínas de Bactérias/genética , Genômica/métodos , Methylobacterium/genética , Cofator PQQ/biossíntese , Carotenoides/metabolismo , Regulação Bacteriana da Expressão Gênica , Tamanho do Genoma , Methylobacterium/isolamento & purificação , Methylobacterium/metabolismo , Mutagênese , Microbiologia do Solo , Ubiquinona/análogos & derivados , Ubiquinona/biossíntese , Águas Residuárias/microbiologia
7.
J Neurosci ; 39(31): 6095-6107, 2019 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-31160538

RESUMO

T-stellate cells in the ventral cochlear nucleus (VCN) form an ascending pathway that conveys spectral information from the cochlea to brainstem nuclei, the inferior colliculi, and the thalamus. The tonotopic array of T-stellate cells enhances the encoding of spectral peaks relative to their auditory nerve fiber inputs. The alignment of local collaterals and T-stellate cell dendrites within the isofrequency lamina suggests that the cells make connections within the isofrequency lamina in which they reside. Recordings from pairs of T-stellate cells in mice of both sexes revealed that firing in the presynaptic cell evoked responses in the postsynaptic cell when presynaptic firing was paired with depolarization of the postsynaptic cell. After such experimental coactivation, presynaptic firing evoked EPSCs of uniform amplitude whose frequency depended on the duration of depolarization and diminished over minutes. Nitric oxide (NO) donors evoked EPSCs in T-stellate cells but not in the other types of principal cells. Blockers of neuronal nitric oxide synthase (nNOS) and of NMDA receptors blocked potentiation, indicating that NO mediates potentiation. nNOS and its receptor, guanylate cyclase (NO-GC), are expressed in somata of T-stellate cells. Excitatory interconnections were bidirectional and polysynaptic, indicating that T-stellate cells connect in networks. Positive feedback provided by temporarily potentiated interconnections between T-stellate cells could enhance the gain of auditory nerve excitation in proportion to the excitation, generating a form of short-term central gain control that could account for the ability of T-stellate cells to enhance the encoding of spectral peaks.SIGNIFICANCE STATEMENT T-stellate cells are interconnected through synapses that have a previously undescribed form of temporary, nitric oxide-mediated plasticity. Coactivation of neighboring cells enhances the activation of an excitatory network that feeds back on itself by enhancing the probability of EPSCs. Although there remain gaps in our understanding of how the interconnections revealed in slices contribute to hearing, our findings have interesting implications. Positive feedback through a network of interconnections could account for how T-stellate cells are able to encode spectral peaks over a wider range of intensities than many of their auditory nerve inputs (Blackburn and Sachs, 1990; May et al., 1998). The magnitude of the gain may itself be plastic because neuronal nitric oxide synthase increases when animals have tinnitus (Coomber et al., 2015).


Assuntos
Vias Auditivas/fisiologia , Percepção Auditiva/fisiologia , Núcleo Coclear/fisiologia , Plasticidade Neuronal/fisiologia , Neurônios/metabolismo , Óxido Nítrico/metabolismo , Animais , Feminino , Masculino , Camundongos
8.
BMC Infect Dis ; 20(1): 389, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32487026

RESUMO

BACKGROUND: Intracranial infections with Corynebacterium striatum (C. striatum) have been described sporadically in the literature over the last two decades. However, C. striatum meningitis combined with multiple abscesses has not been published before. CASE PRESENTATION: In this report, we describe the clinical and imaging findings in a 54-year-old woman with meningitis caused by C. striatum and combined with suspected brain and lung abscesses. This patient who underwent multiple fractures and a recent cut presented with headache and paraphasia. C. striatum was isolated in cerebrospinal fluid and supposedly transmitted from the skin purulent wound through blood. The patient was treated with intravenous vancomycin and had a transient improvement, but died finally. Multiple abscesses, especially in the brain, could be a reason to explain her conditions were deteriorating rapidly. CONCLUSIONS: Note that C. striatum can cause life-threatening infections. Early identification and diagnosis, early administration of antibiotics to which the bacterium is susceptible, and treatment of complications will be beneficial in patients with C. striatum-related infection.


Assuntos
Abscesso Encefálico/microbiologia , Infecções por Corynebacterium/complicações , Abscesso Pulmonar/microbiologia , Meningites Bacterianas/microbiologia , Antibacterianos/uso terapêutico , Abscesso Encefálico/diagnóstico por imagem , Abscesso Encefálico/tratamento farmacológico , Líquido Cefalorraquidiano/microbiologia , Corynebacterium/isolamento & purificação , Corynebacterium/patogenicidade , Infecções por Corynebacterium/tratamento farmacológico , Feminino , Humanos , Traumatismos da Perna/microbiologia , Abscesso Pulmonar/diagnóstico por imagem , Abscesso Pulmonar/tratamento farmacológico , Meningites Bacterianas/complicações , Meningites Bacterianas/tratamento farmacológico , Pessoa de Meia-Idade , Vancomicina/uso terapêutico
9.
Biochem Biophys Res Commun ; 503(3): 1356-1363, 2018 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-30007438

RESUMO

High-fat diet (HFD) is known to promote atherosclerosis which accelerates the development of atherosclerotic cardiovascular diseases. Vascular dysfunction characterized by inflammation and lipid accumulation is common in atherosclerosis caused by HFD. The specific effects of HFD on blood vessels and the underlying mechanisms need to be further clarified. Toll-like receptor 4 (TLR4) is a key contributing factor in atherosclerosis and TLR4 deficiency protects vascular smooth muscle cells against inflammatory responses and lipid accumulation in vitro. However, the physiological significance of TLR4 signaling in HFD-induced changes is unknown. In this study, we observed that HFD feeding increased body weight, circulating inflammatory cytokines and lipid accumulation in the aorta of wild-type mice but apart from increasing body weight, did not affect the TLR4 knockout mice. TLR4 expression increased significantly in the arterial walls after receiving HFD treatment, while that of the co-localizing PPARγ and ABCG1 markedly decreased. TLR4 deficiency reversed the HFD-induced attenuation of PPARγ and ABCG1. In conclusion, TLR4 mediates HFD induced increase in body weight, inflammation and aortic lipid accumulation through, at least partly, the PPARγ/ABCG1 signaling pathway. Therefore, interfering with TLR4 signaling is a viable therapeutic option in diet induced atherosclerosis.


Assuntos
Membro 1 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Dieta Hiperlipídica/efeitos adversos , Inflamação/metabolismo , Músculo Liso Vascular/metabolismo , PPAR gama/metabolismo , Receptor 4 Toll-Like/metabolismo , Animais , Ensaio de Imunoadsorção Enzimática , Inflamação/patologia , Lipídeos/química , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Músculo Liso Vascular/patologia , Transdução de Sinais , Receptor 4 Toll-Like/deficiência
10.
Cell Tissue Res ; 368(1): 145-157, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27807703

RESUMO

Toll-like receptor 4 (TLR4) plays critical roles in vascular inflammation, lipid accumulation and atherosclerosis development. However, the mechanisms underlying these processes are still not well established, especially in vascular smooth muscle cells (VSMCs). ATP-binding cassette transporter G1 (ABCG1) is one of the key genes mediating inflammation and cellular lipid accumulation. The function of TLR4 in regulating the expression of ABCG1 and the underlying molecular mechanisms remain to be elucidated. In this study, we cultured VSMCs from the thoracic aortas of mice and treated the cells with 50 µg/ml oxidized low-density lipoprotein (oxLDL) to activate TLR4 signaling. We observed that activating TLR4 with oxLDL induced inflammatory responses and lipid accumulation in VSMCs. The expression of peroxisome proliferator-activated receptor gamma (PPARγ), liver X receptor alpha (LXRα) and ABCG1 was inhibited by TLR4 activation. However, these effects could be reversed by knocking out TLR4. PPARγ activation by rosiglitazone rescued LXRα and ABCG1 expression and reduced TLR4-induced inflammation and lipid accumulation. Silencing PPARγ expression with a specific small interfering RNA (siRNA) inhibited LXRα and ABCG1 expression and, importantly, enhanced TLR4-induced inflammation and lipid accumulation. In conclusion, ABCG1 expression was down-regulated by TLR4, which induces inflammation and lipid accumulation in VSMCs via PPARγ/LXRα signaling. These findings indicate a novel molecular mechanism underlying TLR4-induced inflammation and lipid accumulation.


Assuntos
Membro 1 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Inflamação/patologia , Metabolismo dos Lipídeos , Receptores X do Fígado/metabolismo , Miócitos de Músculo Liso/metabolismo , Miócitos de Músculo Liso/patologia , PPAR gama/metabolismo , Receptor 4 Toll-Like/metabolismo , Animais , Regulação para Baixo/efeitos dos fármacos , Inativação Gênica/efeitos dos fármacos , Metabolismo dos Lipídeos/efeitos dos fármacos , Lipoproteínas LDL/farmacologia , Camundongos Knockout , Modelos Biológicos , Músculo Liso Vascular/patologia , Miócitos de Músculo Liso/efeitos dos fármacos , Rosiglitazona , Transdução de Sinais/efeitos dos fármacos , Tiazolidinedionas/farmacologia , Receptor 4 Toll-Like/deficiência
11.
PLoS Genet ; 10(12): e1004823, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25473838

RESUMO

Tonotopy is a fundamental organizational feature of the auditory system. Sounds are encoded by the spatial and temporal patterns of electrical activity in spiral ganglion neurons (SGNs) and are transmitted via tonotopically ordered processes from the cochlea through the eighth nerve to the cochlear nuclei. Upon reaching the brainstem, SGN axons bifurcate in a stereotyped pattern, innervating target neurons in the anteroventral cochlear nucleus (aVCN) with one branch and in the posteroventral and dorsal cochlear nuclei (pVCN and DCN) with the other. Each branch is tonotopically organized, thereby distributing acoustic information systematically along multiple parallel pathways for processing in the brainstem. In mice with a mutation in the receptor guanylyl cyclase Npr2, this spatial organization is disrupted. Peripheral SGN processes appear normal, but central SGN processes fail to bifurcate and are disorganized as they exit the auditory nerve. Within the cochlear nuclei, the tonotopic organization of the SGN terminal arbors is blurred and the aVCN is underinnervated with a reduced convergence of SGN inputs onto target neurons. The tonotopy of circuitry within the cochlear nuclei is also degraded, as revealed by changes in the topographic mapping of tuberculoventral cell projections from DCN to VCN. Nonetheless, Npr2 mutant SGN axons are able to transmit acoustic information with normal sensitivity and timing, as revealed by auditory brainstem responses and electrophysiological recordings from VCN neurons. Although most features of signal transmission are normal, intermittent failures were observed in responses to trains of shocks, likely due to a failure in action potential conduction at branch points in Npr2 mutant afferent fibers. Our results show that Npr2 is necessary for the precise spatial organization typical of central auditory circuits, but that signals are still transmitted with normal timing, and that mutant mice can hear even with these deficits.


Assuntos
Vias Auditivas/anormalidades , Padronização Corporal/genética , Nervo Coclear/anormalidades , Mutação , Receptores do Fator Natriurético Atrial/genética , Potenciais de Ação , Animais , Vias Auditivas/embriologia , Vias Auditivas/metabolismo , Percepção Auditiva/fisiologia , Axônios/fisiologia , Tronco Encefálico/anormalidades , Tronco Encefálico/citologia , Tronco Encefálico/patologia , Cóclea/anormalidades , Cóclea/citologia , Cóclea/patologia , Nervo Coclear/embriologia , Nervo Coclear/patologia , Embrião de Mamíferos , Feminino , Camundongos , Camundongos Transgênicos , Neurônios Aferentes/fisiologia , Gravidez
12.
Mol Biol Rep ; 42(1): 179-86, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25249228

RESUMO

Foam cell formation is the hallmark of atherosclerosis. Both telmisartan and autophagy protect against the development of atherosclerosis. However, it has yet to be elucidated whether telmisartan prevents vascular smooth muscle cell (VSMC)-derived foam cell formation. Vascular smooth muscle cells isolated from the thoracic aorta of male C57BL/6J mice were used for this study. To induce foam cell formation, primary VSMCs were incubated in 80 µg/ml oxLDL for 24 h. LC3, beclin-1, PPARγ, AMPK, p-AMPK, mTOR and p-mTOR expression were determined via Western blot. Lipid accumulation was evaluated via oil red O staining and intracellular total cholesterol level measurement. Our study demonstrated that telmisartan dose-dependently increased the expression of beclin-1, the LC3II/LC3I ratio and the quantity of GFP-labeled autophagosomes, displaying a peak effect at 10 µM. In control siRNA-transfected VSMCs, telmisartan (10 µM) decreased lipid droplet accumulation and the total cholesterol level significantly. In contrast, in Atg7 siRNA-transfected VSMCs, telmisartan failed to attenuate lipid accumulation. In addition, telmisartan dose-dependently increased the expression of PPARγ and p-AMPK and decreased the expression of p-mTOR. GW9662 attenuated the telmisartan-induced increase in PPARγ expression, the LC3-II/LC3-I ratio and p-AMPK expression and the telmisartan-induced decrease in p-mTOR expression. Compound C restored mTOR activity and abolished the increase in the LC3-II/LC3-I ratio. Rapamycin significantly reduced p-mTOR expression and increased the LC3-II/LC3-I ratio. In conclusion, this study provides evidence that the chronic pharmacological activation of the PPARγ-mediated autophagy pathway using telmisartan may represent a promising therapeutic strategy for atherosclerosis.


Assuntos
Autofagia/efeitos dos fármacos , Benzimidazóis/farmacologia , Benzoatos/farmacologia , Músculo Liso Vascular/citologia , Miócitos de Músculo Liso/metabolismo , PPAR gama/metabolismo , Adenilato Quinase/metabolismo , Animais , Relação Dose-Resposta a Droga , Células Espumosas/citologia , Células Espumosas/efeitos dos fármacos , Células Espumosas/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Masculino , Camundongos Endogâmicos C57BL , Miócitos de Músculo Liso/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Telmisartan
13.
ACS Biomater Sci Eng ; 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38775700

RESUMO

Visualizing the whole vascular network system is crucial for understanding the pathogenesis of specific diseases and devising targeted therapeutic interventions. Although the combination of light sheet microscopy and tissue-clearing methods has emerged as a promising approach for investigating the blood vascular network, leveraging the spatial resolution down to the capillary level and the ability to image centimeter-scale samples remains difficult. Especially, as the resolution improves, the issue of photobleaching outside the field of view poses a challenge to image the whole vascular network of adult mice at capillary resolution. Here, we devise a fluorescent microsphere vascular perfusion method to enable labeling of the whole vascular network in adult mice, which overcomes the photobleaching limit during the imaging of large samples. Moreover, by combining the utilization of a large-scale light-sheet microscope and tissue clearing protocols for whole-mouse samples, we achieve the capillary-level imaging resolution (3.2 × 3.2 × 6.5 µm) of the whole vascular network with dimensions of 45 × 15 × 82 mm in adult mice. This method thus holds great potential to deliver mesoscopic resolution images of various tissue organs for whole-animal imaging.

14.
Lab Invest ; 93(8): 880-7, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23774581

RESUMO

Reactive oxygen species (ROS) are associated with inflammation and vasculature dysfunction. This study aimed to investigate the potential role of the ROS on vascular Toll-like receptor 4 (TLR4)-mediated proinflammatory and proliferative phenotype of vascular smooth muscle cells (VSMCs). A wire-induced carotid injury model was used in male TLR4-deficient (TLR4(-/-)) and wild-type C57BL/6J mice to induce neointima formation. In the presence or absence of the ROS scavenger apocynin for 14 days, increased TLR4 and proinflammatory cytokines were observed in wire injury-induced carotid neointima and in platelet-derived growth factor-BB (PDGF-BB)-stimulated VSMCs. The TLR4(-/-) protected the injured carotid from neointimal formation and impaired the cellular proliferation and migration in response to PDGF-BB. Apocynin attenuated intimal hyperplasia. Pre-treatment with apocynin significantly inhibited intracellular ROS generation, accompanied by a significant suppression of TLR4 and proinflammatory cytokines expression, and VSMC proliferation and migration. However, the results were not obvious in TLR4(-/-) condition. These findings highlight the importance of ROS inhibition in TLR4-mediated proinflammatory and proliferative phenotype of VSMCs, and suggest ROS as an essential therapeutic target for TLR4-associated vascular inflammation and vascular diseases.


Assuntos
Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Receptor 4 Toll-Like/metabolismo , Acetofenonas/farmacologia , Animais , Becaplermina , Lesões das Artérias Carótidas/etiologia , Lesões das Artérias Carótidas/metabolismo , Lesões das Artérias Carótidas/patologia , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Hiperplasia/induzido quimicamente , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/patologia , Miócitos de Músculo Liso/efeitos dos fármacos , Miócitos de Músculo Liso/patologia , Neointima/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fenótipo , Proteínas Proto-Oncogênicas c-sis/farmacologia
15.
Psychol Rep ; : 332941231175833, 2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37164938

RESUMO

Sleep time and depression symptoms are important factors affecting cognitive development in adolescents. Based on the China Education Panel Survey (CEPS) database, this study used a two-wave cross-lagged model to examine the bidirectional relationship between sleep time, depression symptoms, and cognitive development. Descriptive statistics showed that Chinese adolescents' cognitive development increased significantly from 7th to 8th grade in junior high school, but unfortunately, their depression level and average sleep time per night demonstrated a slightly deteriorating trend. Correlation analysis showed that there was a relatively stable negative correlation between cognitive development, sleep time, and depression symptoms. Moreover, the cross-lagged model revealed that there was a bidirectional relationship between cognitive development and sleep time, a bidirectional relationship between depression symptoms and sleep time, and a unidirectional relationship between depression symptoms and cognitive development. Male adolescents in the subgroup were consistent with the total sample. Among female adolescents, only cognitive development and sleep time have a bidirectional relationship, while depression symptoms and cognitive development, and depression symptoms and sleep time have a unidirectional relationship. Therefore, it is of significance to take targeted action to promote cognitive development and healthy growth in adolescents worldwide.

16.
J Intell ; 11(5)2023 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-37233337

RESUMO

Everyone's time is limited, and there is competition between different aspects of time use; this requires comprehensive consideration of the effects of different aspects of time use on cognitive achievement in adolescents. This study uses a dataset of 11,717 students from a nationally representative large-scale survey project conducted in 2013 to 2014 to clarify the relationship between time use (including working on homework, playing sports, surfing the Internet, watching TV, and sleeping) and cognitive achievement among Chinese adolescents, and explores the mediating role of depression symptoms in the relationship between time use and cognitive achievement. The results of the correlation analysis show that the average daily time spent on homework, playing sports, and sleeping is significantly positively correlated with cognitive achievement (p < 0.01), while time spent surfing the Internet and watching TV are significantly negatively correlated with cognitive achievement (p < 0.01). The results of the mediating effect model show that depression symptoms play a mediating role in the relationship between time use and cognitive achievement among Chinese adolescents. Specifically, time spent playing sports (indirect effect = 0.008, p < 0.001) and sleeping (indirect effect = 0.015, p < 0.001) have a positive effect on cognitive achievement when using depression symptoms as mediators; time spent on homework (indirect effect = -0.004, p < 0.001), surfing the Internet (indirect effect = -0.002, p = 0.046), and watching TV (indirect effect = -0.005, p < 0.001) have a negative effect on cognitive achievement when using depression symptoms as mediators. This study contributes to the understanding of the relationship between time use and cognitive achievement among Chinese adolescents.

17.
Behav Sci (Basel) ; 13(10)2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37887526

RESUMO

The parent‒child relationship is a crucial factor in promoting adolescent mental health. However, the current evidence on the relationship between parent‒child relationships and adolescent conscientiousness and neuroticism, as well as the directionality of these relationships, remains limited. In particular, there is a lack of analysis focusing on Chinese middle school students. Based on a sample of 8437 students from the China Education Panel Survey (CEPS) database, this study empirically examined the bidirectional relationships between parent‒child relationships, conscientiousness and neuroticism among Chinese middle school students, with specific emphasis on the significant role of parent‒child relationships in the development of conscientiousness and neuroticism. Descriptive statistical results indicated that during the seventh and eighth grades of Chinese middle school students, the closeness of their parent‒child relationships with both parents decreased, while the level of conscientiousness showed a slight decrease, and neuroticism showed an increasing trend. Correlational results demonstrated a significant positive correlation between parent‒child relationships and conscientiousness and a significant negative correlation between parent‒child relationships and neuroticism. Further analysis using cross-lagged models revealed that parent‒child relationships significantly positively predicted subsequent conscientiousness development, and conscientiousness significantly positively predicted subsequent parent‒child relationships. Parent‒child relationships significantly negatively predicted subsequent neuroticism development, and neuroticism levels also significantly negatively predicted subsequent parent‒child relationships. Based on these findings, we believe that there is a need to strengthen parent‒child relationships and to recognize the important role that both mothers and fathers play in the healthy development of their children. Both parents should actively contribute to their children's upbringing and take responsibility for their family education.

18.
Front Neurol ; 14: 1213090, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37830096

RESUMO

We report the case of a 31-year-old Chinese woman with a chief complaint of weakness in the lower limbs, which was diagnosed as limb-girdle muscular dystrophy 2B (LGMD2B) with compound heterozygous mutations of the DYSF gene. Meanwhile, this woman is an asymptomatic carrier with the mutation of the X-linked DMD gene. The electromyography, muscle MRI, and muscle biopsy indicated a chronic myogenic injury with dysferlin deletion. As a result of genetic testing, compound heterozygous G-to-T base substitution at position 5,497 in exon 49 of the DYSF gene, leading to a codon change from glutamic acid to termination codon at position 1,833, and a heterozygous C-to-G base change at position 4,638 + 8 in intron 42 of the DYSF gene with a consequence of splice, which has never been reported, were identified as candidate causative mutations. Unfortunately, DMD gene mutation c.3921+12A>G of the DMD gene on the X chromosome was also found in this patient. Finally, the patient was diagnosed as LGMD2B clinically and genetically. In the previous 2 years, the patient's lower limb weakness became slightly worse, resulting in even the total distance walked than before. Fortunately, during the follow-up, her son had not shown slowness or limitation of movement. Genetic testing by next-generation sequencing confirmed the final diagnosis of LGMD2B, and we identified the novel compound heterozygous variants in the DYSF gene, which is of great significance to the accurate diagnosis of genetically coded diseases. Much attention needs to be paid in clinics toward hereditary neuromuscular diseases with multiple pathogenic gene mutations. Genetic counseling and clinical follow-up should be the priorities in future, and promising treatments are also worth exploring.

19.
eNeuro ; 10(3)2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36792362

RESUMO

The cochlear nuclei (CNs) receive sensory information from the ear and perform fundamental computations before relaying this information to higher processing centers. These computations are performed by distinct types of neurons interconnected in circuits dedicated to the specialized roles of the auditory system. In the present study, we explored the use of voltage imaging to investigate CN circuitry. We tested two approaches based on fundamentally different voltage sensing technologies. Using a voltage-sensitive dye we recorded glutamate receptor-independent signals arising predominantly from axons. The mean conduction velocity of these fibers of 0.27 m/s was rapid but in range with other unmyelinated axons. We then used a genetically-encoded hybrid voltage sensor (hVOS) to image voltage from a specific population of neurons. Probe expression was controlled using Cre recombinase linked to c-fos activation. This activity-induced gene enabled targeting of neurons that are activated when a mouse hears a pure 15-kHz tone. In CN slices from these animals auditory nerve fiber stimulation elicited a glutamate receptor-dependent depolarization in hVOS probe-labeled neurons. These cells resided within a band corresponding to an isofrequency lamina, and responded with a high degree of synchrony. In contrast to the axonal origin of voltage-sensitive dye signals, hVOS signals represent predominantly postsynaptic responses. The introduction of voltage imaging to the CN creates the opportunity to investigate auditory processing circuitry in populations of neurons targeted on the basis of their genetic identity and their roles in sensory processing.


Assuntos
Núcleo Coclear , Camundongos , Animais , Neurônios/fisiologia , Axônios/fisiologia , Percepção Auditiva , Audição , Vias Auditivas/fisiologia
20.
Psychol Res Behav Manag ; 15: 1481-1487, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35719193

RESUMO

Purpose: This study aimed to investigate the longitudinal relationship between anxiety and self-esteem among college students. Participants and methods: A total of 2473 Chinese college students were tracked, with their anxiety and self-esteem levels collected annually over the four academic years. The study employed a four-wave random intercept cross-lagged panel model to examine the prospective relationship between anxiety and self-esteem. Results: The anxiety levels were negatively associated with self-esteem over campus life. Results of the four-wave cross-lagged panel model revealed that low self-esteem maintained having subsequent negative impacts on students' anxiety levels, while the effects became progressively stronger over the four academic years. Meanwhile, no significant prospective effects were identified of anxiety levels on self-esteem. Conclusion: The study confirmed self-esteem as one of the leading contributors to anxiety for college students and emphasized the importance of nourishing the self-esteem of students to alleviate their anxiety issues and improve their mental health at college.

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