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1.
J Am Chem Soc ; 146(23): 16097-16104, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38805671

RESUMO

Communication between cells is crucial to the survival of both uni- and multicellular organisms. The primary mode of communication involves chemical cues. There is great current interest in mimicking this behavior in synthetic cells to understand the physical basis of intercellular communication and design collective functional behavior. Using liposomal cell mimics, we demonstrate how a chemical input can elicit a mechanical response (enhanced motility). We employed a single substrate to trigger enzyme cascade-induced control of the diffusion of up to three different liposome populations. Furthermore, substrate competition allows temporal control over enhanced diffusion. The use of enzyme cascades to propagate chemical signals provides a robust and efficient mechanism for diverse populations of protocells to coordinate their motion in response to signals from each other.


Assuntos
Lipossomos , Lipossomos/química , Lipossomos/metabolismo , Difusão
2.
Cardiovasc Diabetol ; 23(1): 121, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38581024

RESUMO

BACKGROUND: This study investigates the relationship between triglyceride-glucose (TyG) index trajectories and the results of ablation in patients with stage 3D atrial fibrillation (AF). METHODS: A retrospective cohort study was carried out on patients who underwent AF Radiofrequency Catheter Ablation (RFCA) at the Cardiology Department of the Fourth Affiliated Hospital of Zhejiang University and Taizhou Hospital of Zhejiang Province from January 2016 to December 2022. The main clinical endpoint was determined as the occurrence of atrial arrhythmia for at least 30 s following a 3-month period after ablation. Using a latent class trajectory model, different trajectory groups were identified based on TyG levels. The relationship between TyG trajectory and the outcome of AF recurrence in patients was assessed through Kaplan-Meier survival curve analysis and multivariable Cox proportional hazards regression model. RESULTS: The study included 997 participants, with an average age of 63.21 ± 9.84 years, of whom 630 were males (63.19%). The mean follow-up period for the participants was 30.43 ± 17.75 months, during which 200 individuals experienced AF recurrence. Utilizing the minimum Bayesian Information Criterion (BIC) and the maximum Entropy principle, TyG levels post-AF RFCA were divided into three groups: Locus 1 low-low group (n = 791), Locus 2 low-high-low group (n = 14), and Locus 3 high-high group (n = 192). Significant differences in survival rates among the different trajectories were observed through the Kaplan-Meier curve (P < 0.001). Multivariate Cox regression analysis showed a significant association between baseline TyG level and AF recurrence outcomes (HR = 1.255, 95% CI: 1.087-1.448). Patients with TyG levels above 9.37 had a higher risk of adverse outcomes compared to those with levels below 8.67 (HR = 2.056, 95% CI: 1.335-3.166). Furthermore, individuals in Locus 3 had a higher incidence of outcomes compared to those in Locus 1 (HR = 1.580, 95% CI: 1.146-2). CONCLUSION: The TyG trajectories in patients with stage 3D AF are significantly linked to the outcomes of AF recurrence. Continuous monitoring of TyG levels during follow-up may help in identifying patients at high risk of AF recurrence, enabling the early application of effective interventions.


Assuntos
Fibrilação Atrial , Ablação por Cateter , Masculino , Humanos , Pessoa de Meia-Idade , Idoso , Feminino , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/cirurgia , Fibrilação Atrial/etiologia , Estudos Retrospectivos , Teorema de Bayes , Resultado do Tratamento , Fatores de Risco , Ablação por Cateter/efeitos adversos , Ablação por Cateter/métodos , Recidiva
3.
Opt Lett ; 49(9): 2365-2368, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38691720

RESUMO

Near-infrared nanosecond (ns) single-longitudinal-mode (SLM) pulse light generated from an optical parametric oscillator (OPO) is an important source in nonlinear optics and high-precision spectral analysis. In this Letter, a stable SLM near-infrared ns pulse light source generated from the OPO is presented, which is achieved by developing a seed-injection automatic locking technique based on a pulse-integrated photodetector (PIPD). Depending on the PIPD, the peak power of the pulse light detected by the photodiode is converted to the average power by integrating several pulses. As a result, the detector saturation is thoroughly eliminated, and the interference signal including the resonance point between seed and pulse lights can easily be attained by scanning the resonator length. On this basis, a microcontroller unit (MCU) is employed to realize automatic locking by looking for the minimum value of the interference signal. Finally, a SLM 824 nm pulse light source with an output power of 20.5 W and a linewidth of 51.42 MHz is obtained. The presented method can pave the way to implement a low-cost and compact high-average-power SLM pulse OPO.

4.
Opt Lett ; 49(11): 3058-3061, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38824327

RESUMO

Lensless imagers based on diffusers or encoding masks enable high-dimensional imaging from a single-shot measurement and have been applied in various applications. However, to further extract image information such as edge detection, conventional post-processing filtering operations are needed after the reconstruction of the original object images in the diffuser imaging systems. Here, we present the concept of a temporal compressive edge detection method based on a lensless diffuser camera, which can directly recover a time sequence of edge images of a moving object from a single-shot measurement, without further post-processing steps. Our approach provides higher image quality during edge detection, compared with the "conventional post-processing method." We demonstrate the effectiveness of this approach by both numerical simulation and experiments. The proof-of-concept approach can be further developed with other image post-processing operations or versatile computer vision assignments toward task-oriented intelligent lensless imaging systems.

5.
Biomacromolecules ; 25(5): 3087-3097, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38584438

RESUMO

Heparan sulfate proteoglycans (HSPGs) play a crucial role in regulating cancer growth and migration by mediating interactions with growth factors. In this study, we developed a self-assembling peptide (S1) containing a sulfate group to simulate the contiguous sulfated regions (S-domains) in heparan sulfate for growth factor binding, aiming to sequester growth factors like VEGF. Spectral and structural studies as well as simulation studies suggested that S1 self-assembled into nanostructures similar to the heparan sulfate chains and effectively bound to VEGF. On cancer cell surfaces, S1 self-assemblies sequestered VEGF, leading to a reduction in VEGF levels in the medium, consequently inhibiting cancer cell growth, invasion, and angiogenesis. This study highlights the potential of self-assembling peptides to emulate extracellular matrix functions, offering insights for future cancer therapeutic strategies.


Assuntos
Invasividade Neoplásica , Peptídeos , Fator A de Crescimento do Endotélio Vascular , Humanos , Fator A de Crescimento do Endotélio Vascular/metabolismo , Peptídeos/química , Peptídeos/farmacologia , Movimento Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Heparitina Sulfato/química , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Neoplasias/metabolismo , Proliferação de Células/efeitos dos fármacos , Neovascularização Patológica/tratamento farmacológico
6.
Mol Biol Rep ; 51(1): 351, 2024 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-38400865

RESUMO

The nervous system possesses the remarkable ability to undergo changes in order to store information; however, it is also susceptible to damage caused by invading pathogens or neurodegenerative processes. As a member of nucleotide-binding oligomerization domain-like receptor (NLR) family, the NLRP6 inflammasome serves as a cytoplasmic innate immune sensor responsible for detecting microbe-associated molecular patterns. Upon activation, NLRP6 can recruit the adapter protein apoptosis-associated speck-like protein (ASC) and the inflammatory factors caspase-1 or caspase-11. Consequently, inflammasomes are formed, facilitating the maturation and secretion of pro-inflammatory cytokines such as inflammatory factors-18 (IL-18) and inflammatory factors-1ß (IL-1ß). Precise regulation of NLRP6 is crucial for maintaining tissue homeostasis, as dysregulated inflammasome activation can contribute to the development of various diseases. Furthermore, NLRP6 may also play a role in the regulation of extraintestinal diseases. In cells of the brain, such as astrocytes and neurons, NLRP6 inflammasome are also present. Here, the assembly and subsequent activation of caspase-1 mediated by NLRP6 contribute to disease progression. This review aims to discuss the structure and function of NLRP6, explain clearly the mechanisms that induce and activate NLRP6, and explore its role within the central and peripheral nervous system.


Assuntos
Inflamassomos , Doenças do Sistema Nervoso , Humanos , Inflamassomos/metabolismo , Citocinas/metabolismo , Caspase 1/metabolismo , Apoptose , Doenças do Sistema Nervoso/genética , Caspases , Peptídeos e Proteínas de Sinalização Intracelular
7.
Aging Clin Exp Res ; 36(1): 37, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38345751

RESUMO

BACKGROUND: Non-invasive brain stimulation (NIBS) is a burgeoning approach with the potential to significantly enhance cognition and functional abilities in individuals who have undergone a stroke. However, the current evidence lacks robust comparisons and rankings of various NIBS methods concerning the specific stimulation sites and parameters used. To address this knowledge gap, this systematic review and meta-analysis seek to offer conclusive evidence on the efficacy and safety of NIBS in treating post-stroke cognitive impairment. METHODS: A systematic review of randomized control trials (RCT) was performed using Bayesian network meta-analysis. We searched RCT in the following databases until June 2022: Cochrane Central Register of Controlled Trials (CENTRAL), PUBMED, and EMBASE. We compared any active NIBS to control in terms of improving cognition function and activities of daily living (ADL) capacity following stroke. RESULTS: After reviewing 1577 retrieved citations, a total of 26 RCTs were included. High-frequency (HF)-repetitive transcranial magnetic stimulation (rTMS) (mean difference 2.25 [95% credible interval 0.77, 3.66]) was identified as a recommended approach for alleviating the global severity of cognition. Dual-rTMS (27.61 [25.66, 29.57]) emerged as a favorable technique for enhancing ADL function. In terms of stimulation targets, the dorsolateral prefrontal cortex exhibited a higher ranking in relation to the global severity of cognition. CONCLUSIONS: Among various NIBS techniques, HF-rTMS stands out as the most promising intervention for enhancing cognitive function. Meanwhile, Dual-rTMS is highly recommended for improving ADL capacity.


Assuntos
Disfunção Cognitiva , Acidente Vascular Cerebral , Estimulação Transcraniana por Corrente Contínua , Humanos , Estimulação Transcraniana por Corrente Contínua/métodos , Metanálise em Rede , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/terapia , Encéfalo , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/terapia
8.
Artigo em Inglês | MEDLINE | ID: mdl-38430154

RESUMO

Context: Schizophrenia is a common and clinically disabling mental disorder. Many patients with schizophrenia smoke. Research on the effects of smoking on schizophrenia's symptoms are inconsistent. Objective: The study intended to investigate the smoking status of patients with stable schizophrenia to determine the effects of smoking on schizophrenia-related symptoms. Design: The research team performed an case-control study. Setting: The study took place at Beijing Huilongguan Hospital in Beijing, Changping District, China. Participants: Participants were 160 patients at the hospital who had been diagnosed with stable schizophrenia between April 2018 and March 2020. Groups: The research team divided participants into two groups based on their current smoking status: (1) a smoking group with 72 participants and (2) a nonsmoking group with 88 participants. Outcome Measures: The research team: (1) examined the types of antipsychotic drugs that participants received; (2) used a schizophrenia-related scale, the Positive and Negative Syndrome Scale (PANSS), to examine participants' status; (3) examined the smoking habits of the smoking group; and (4) analyzed the correlation between the PANSS score and the smoking group's smoking index. Results: No significant difference existed between the groups in the type of medicine used (P > .05). The smoking group's PANSS total (P = .014), positive symptom (P = .039), and negative symptom (P = .003) scores were significantly lower than those of the nonsmoking group (P < .05). No significant difference existed between the groups in the general psychopathological symptom score (P > .05). The smoking group started smoking between 13 and 24 years of age, with an mean age of 19.11 ± 4.10 years. The group smoked 10-30 cigarettes/d, with a mean smoking amount of 18.4 ± 3.1 cigarettes/d, and the smoking index was 344.7 ± 48.0. The smoking group's smoking index was significantly negatively correlated with the positive symptom, negative symptom, and total PANSS scores (all P = .000). No correlation existed between the smoking index and the general psychopathological symptom score (P > .05). Conclusions: Smoking patients with stable schizophrenia generally exhibit fewer symptoms than nonsmoking patients, which relate to the alleviation of mental tension that smoking can provide.

9.
Chem Biodivers ; 21(5): e202400031, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38448389

RESUMO

Ulcerative colitis has been widely concerned for its persistent upward trend, and the sustained overproduction of pro-inflammatory cytokines such as IL-6 remains a crucial factor in the development of UC. Therefore, the identification of new effective drugs to block inflammatory responses is an urgent and viable therapeutic strategy for UC. In our research, twenty-three 6-acylamino/sulfonamido benzoxazolone derivatives were synthesized, characterized, and evaluated for anti-inflammatory activity against NO and IL-6 production in LPS-induced RAW264.7 cells. The results demonstrated that most of the target compounds were capable of reducing the overexpression of NO and IL-6 to a certain degree. For the most active compounds 3i, 3j and 3 l, the inhibitory activities were superior or equivalent to those of the positive drug celecoxib with a dose-dependent relationship. Furthermore, animal experiments revealed that active derivatives 3i, 3j and 3 l exhibited definitive therapeutical effect on DSS induced ulcerative colitis in mice by mitigating weight loss and DAI score while decreasing levels of pro-inflammatory cytokines such as IL-6 and IFN-γ, simultaneously increasing production of anti-inflammatory cytokines IL-10. In addition, compounds 3i, 3j and 3 l could also inhibit the oxidative stress to alleviate ulcerative colitis by decreasing MDA and MPO levels. These finding demonstrated that compounds 3i, 3j and 3 l hold significant potential as novel therapeutic agents for ulcerative colitis.


Assuntos
Benzoxazóis , Colite Ulcerativa , Interleucina-6 , Animais , Colite Ulcerativa/tratamento farmacológico , Camundongos , Interleucina-6/antagonistas & inibidores , Interleucina-6/metabolismo , Benzoxazóis/química , Benzoxazóis/farmacologia , Benzoxazóis/síntese química , Células RAW 264.7 , Relação Estrutura-Atividade , Lipopolissacarídeos/antagonistas & inibidores , Lipopolissacarídeos/farmacologia , Óxido Nítrico/antagonistas & inibidores , Óxido Nítrico/metabolismo , Óxido Nítrico/biossíntese , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/síntese química , Anti-Inflamatórios/uso terapêutico , Sulfato de Dextrana , Descoberta de Drogas , Estrutura Molecular , Relação Dose-Resposta a Droga
10.
Molecules ; 29(7)2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38611820

RESUMO

The level of fluoride ions (F-) in the human body is closely related to various pathological and physiological states, and the rapid detection of F- is important for studying physiological processes and the early diagnosis of diseases. In this study, the detailed sensing mechanism of a novel high-efficiency probe (PBT) based on 2-(2'-hydroxyphenyl)-benzothiazole derivatives towards F- has been fully investigated based on density functional theory (DFT) and time-dependent density functional theory (TDDFT) methods. F- attacks the O-P bond of PBT to cleavage the dimethylphosphinothionyl group, and the potential products were evaluated by Gibbs free energy and spectroscopic analyses, which ultimately identified the product as HBT-Enol1 with an intramolecular hydrogen bond. Bond parameters, infrared vibrational spectroscopy and charge analysis indicate that the hydrogen bond is enhanced at the excited state (S1), favoring excited state intramolecular proton transfer (ESIPT). The mild energy barrier further evidences the occurrence of ESIPT. Combined with frontier molecular orbital (FMO) analysis, the fluorescence quenching of PBT was attributed to the photoinduced electron transfer (PET) mechanism and the fluorescence turn-on mechanism of the product was attributed to the ESIPT process of HBT-Enol1.

11.
Angew Chem Int Ed Engl ; 63(6): e202311556, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38079027

RESUMO

Nanoscale enzymes anchored to surfaces act as chemical pumps by converting chemical energy released from enzymatic reactions into spontaneous fluid flow that propels entrained nano- and microparticles. Enzymatic pumps are biocompatible, highly selective, and display unique substrate specificity. Utilizing these pumps to trigger self-propelled motion on the macroscale has, however, constituted a significant challenge and thus prevented their adaptation in macroscopic fluidic devices and soft robotics. Using experiments and simulations, we herein show that enzymatic pumps can drive centimeter-scale polymer sheets along directed linear paths and rotational trajectories. In these studies, the sheets are confined to the air/water interface. With the addition of appropriate substrate, the asymmetric enzymatic coating on the sheets induces chemically driven, buoyancy flows that controllably propel the sheet's motion on the air/water interface. The directionality and speed of the motion can be tailored by changing the pattern of the enzymatic coating, type of enzyme, and nature and concentration of the substrate. This work highlights the utility of biocompatible enzymes for generating motion in macroscale fluidic devices and robotics and indicates their potential utility for in vivo applications.


Assuntos
Enzimas , Enzimas/química
12.
Angew Chem Int Ed Engl ; 63(6): e202316242, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-37939352

RESUMO

The interplay of interfacial tensions on droplets results in a range of self-powered motions that mimic those of living systems and serve as a tunable model to understand their complex non-equilibrium behavior. Spontaneous shape deformations and oscillations are crucial features observed in nature but difficult to incorporate in synthetic artificial systems. Here, we report sessile oil-in-water emulsions that exhibit rapid oscillating behavior. The oscillations depend on the nature and concentration of the surfactant, the chemical composition of the oil, and the wettability of the solid substrate. The rapid changes in the contact angle per oscillation are observed using side-view optical microscopy. We propose that the changes in the interfacial tension of the oil droplets is due to the partitioning of the surfactant into the oil phase and the movement of self-emulsified oil out of the parent droplets giving rise to the rhythmic variation in droplet contact-line. The ability to control and understand droplet oscillation can help model similar oscillations in out-of-equilibrium systems in nature and reproduce biomimetic behavior in artificial systems for various applications, such as microfluidic lab-on-a-chip and adaptive materials.

13.
Chembiochem ; 24(5): e202200652, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36592168

RESUMO

Heparin is a commonly used anticoagulant in clinical practice; however, excessive heparin can cause serious adverse reactions. Convenient and accurate detection of heparin levels is thus very important. In this research, a pyrene-based self-assembling fluorescent peptide PyFFRRR was designed for simple, selective, and efficient heparin detection. The guanidine groups in the arginine residues of PyFFRRR bind tightly with heparin, which is highly sulfated, through electrostatic interactions. Charge neutralization facilitated the self-assembly of PyFFRRR, resulting in its spectral response changing from deep blue monomer fluorescence to green excimer fluorescence. PyFFRRR exhibited excellent sensitivity and selectivity for ratiometric detection of heparin. The binding mechanism was investigated by using spectral and simulation tools, and structural observation. Finally, PyFFRRR was employed in human serum samples for ratiometric detection of heparin.


Assuntos
Corantes Fluorescentes , Heparina , Humanos , Heparina/química , Corantes Fluorescentes/química , Peptídeos/química , Anticoagulantes , Espectrometria de Fluorescência/métodos , Pirenos/química
14.
Opt Express ; 31(11): 17629-17644, 2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-37381492

RESUMO

Manufacturing sharp features is one of the most desired requirements for lithography. Here, we demonstrate a dual-path self-aligned polarization interference lithography (Dp-SAP IL) for fabricating periodic nanostructures, featuring high-steepness and high-uniformization. Meanwhile, it can manufacture quasicrystals with adjustable rotation symmetry. We reveal the change of the non-orthogonality degree under different polarization states and incident angles. We find that incident light's transverse electric (TE) wave results in high interference contrast at arbitrary incident angles, with a minimum contrast of 0.9328, that is, realizing the self-alignment of the polarization state of incident light and reflected light. We experimentally demonstrate this approach by fabricating a series of diffraction gratings with periods ranging from 238.3 nm to 851.6 nm. The steepness of each grating is greater than 85 degrees. Different from the traditional interference lithography system, Dp-SAP IL realizes a structure color using two mutually perpendicular and non-interference paths. One path is for the photolithography of patterns onto the sample, and the other path is for generating nanostructures on the patterns. Our technique showcases the feasibility of obtaining high contrast interference fringes by simply tuning the polarization, with the potential for cost-effective manufacturing of nanostructures such as quasicrystals and structure color.

15.
Opt Express ; 31(1): 745-754, 2023 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-36607007

RESUMO

All-solid-state continuous-wave (CW) single-frequency tunable Ti:sapphire (Ti:S) laser is an important source in quantum optics and atomic physics. However, intracavity etalon (IE) locking is easily influenced by the intensity noise of the pump source in the low frequency band. In order to address this issue, a differential detector with dual-photodiodes (PDs) is designed and employed in the experiment. Both PDs are used to detect the lights of the pump source and the built Ti:S laser, respectively. As a result, the influence of the intensity noise of the pump source on the stability of the IE locking is successfully eliminated and the IE is stably locked to the oscillating longitudinal-mode of the laser. On this basis, a stable CW single-frequency tunable Ti:S laser is realized. The presented method is beneficial to attain a stable single-frequency tunable laser with immunity to the intensity noise of the pump source.

16.
Opt Express ; 31(9): 14225-14239, 2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-37157291

RESUMO

In this paper, we present a dual-mode adaptive singular value decomposition ghost imaging (A-SVD GI), which can be easily switched between the modes of imaging and edge detection. It can adaptively localize the foreground pixels via a threshold selection method. Then only the foreground region is illuminated by the singular value decomposition (SVD) - based patterns, consequently retrieving high-quality images with fewer sampling ratios. By changing the selecting range of foreground pixels, the A-SVD GI can be switched to the mode of edge detection to directly reveal the edge of objects, without needing the original image. We investigate the performance of these two modes through both numerical simulations and experiments. We also develop a single-round scheme to halve measurement numbers in experiments, instead of separately illuminating positive and negative patterns in traditional methods. The binarized SVD patterns, generated by the spatial dithering method, are modulated by a digital micromirror device (DMD) to speed up the data acquisition. This dual-mode A-SVD GI can be applied in various applications, such as remote sensing or target recognition, and could be further extended for multi-modality functional imaging/detection.

17.
Opt Lett ; 48(19): 4973-4976, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37773363

RESUMO

A high-average-power and narrow-linewidth nanosecond (ns) pulse 824 nm laser is a crucial source for the generation of deep-ultraviolet (DUV) 248 nm laser by means of the sum-frequency process with the 354.5 nm laser. To this purpose, in this Letter, we present a seed-injection-locked high-average-power ns pulse single-longitudinal-mode (SLM) 824 nm laser. By developing a novel, to the best of our knowledge, pulse-saturated seed-injection locking method, disturbance of the pulse laser on the locking of the injected seed laser is successfully eliminated. As a result, the output power of 824 nm laser is up to 21.2 W at the incident pump power of 48.1 W, and the pulse width is 15 ns. Especially, the signal-to-noise ratio of the detected modulated sideband signal exceeds 28 dB, which ensures that the achieved linewidth of the 824 nm laser is as narrow as 38.8 MHz. These results demonstrate the potential of the proposed pulse saturation seed-injection locking OPO cavity for high-power and narrow-linewidth laser applications.

18.
EMBO Rep ; 22(6): e51649, 2021 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-33855783

RESUMO

Pathological TDP-43 aggregation is characteristic of several neurodegenerative diseases, including amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD-TDP); however, how TDP-43 aggregation and function are regulated remain poorly understood. Here, we show that O-GlcNAc transferase OGT-mediated O-GlcNAcylation of TDP-43 suppresses ALS-associated proteinopathies and promotes TDP-43's splicing function. Biochemical and cell-based assays indicate that OGT's catalytic activity suppresses TDP-43 aggregation and hyperphosphorylation, whereas abolishment of TDP-43 O-GlcNAcylation impairs its RNA splicing activity. We further show that TDP-43 mutations in the O-GlcNAcylation sites improve locomotion defects of larvae and adult flies and extend adult life spans, following TDP-43 overexpression in Drosophila motor neurons. We finally demonstrate that O-GlcNAcylation of TDP-43 promotes proper splicing of many mRNAs, including STMN2, which is required for normal axonal outgrowth and regeneration. Our findings suggest that O-GlcNAcylation might be a target for the treatment of TDP-43-linked pathogenesis.


Assuntos
Esclerose Lateral Amiotrófica , Demência Frontotemporal , Esclerose Lateral Amiotrófica/genética , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Humanos , Splicing de RNA , RNA Mensageiro/genética
19.
Inorg Chem ; 62(31): 12565-12572, 2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37498665

RESUMO

Photocatalytic reduction of excess CO2 in the atmosphere to value-added chemicals by visible light can be an effective solution to fuel shortage and global warming. Considering these issues, we designed and successfully synthesized a trinuclear Re(I)-coordinated organic cage (Re-C4R) as the supramolecular photocatalyst. Photophysical, electrochemical properties, and photocatalytic performance comparison of Re-C4R and its mononuclear analogue Re-bpy are discussed in detail. Notably, the covalent linkage of three Re(I) subunits in Re-C4R leads to TONCO = 691 (per Re(I) site in 4 h) more than three times as much as TONCO = 208 of Re-bpy. Compared to Re-bpy, higher current enhancement in the control CV experiments under CO2 was observed for Re-C4R. CO2 adsorption process can be promoted because of the cryptand structure and multiple amine groups of Re-C4R. Moreover, decay lifetimes of Re-C4R are shorter than those of Re-bpy in the ultrafast transient absorption (TA) and photoluminescence (PL) decay spectra, indicating that the trinuclear cryptate structure of Re-C4R could facilitate electron transfer efficiency during CO2 reduction.

20.
Bioorg Chem ; 140: 106812, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37651894

RESUMO

A total of 17 structurally diverse clerodane diterpenoids, including ten undescribed clerodane diterpenoids (tinopanoids K-T, 1-10) and seven known compounds (11-17), were isolated from the vines and leaves of Tinospora crispa. Compound 3 has not only bear the dominant substituents of γ-hydroxy-α, ß-unsaturated-γ-lactone with anti-inflammatory activity, but also a ternary epoxy structure at C-3/C-4. The planar structures and relative configurations of the clerodane diterpenoids were elucidated by spectroscopic data interpretation. The absolute configurations of compounds 1, 4, 8 and 13 were determined by single-crystal X-ray crystallographic, while that of compound 3 was determined using computed ECD data and single crystal X-ray diffraction of related p-bromobenzoate ester (3a). Subsequently, all compounds were evaluated for their inhibitory effect on nitric oxide (NO) production of LPS-activated BV-2 cells, and compounds 3 and 8 exhibited better NO inhibitory potency, with IC50 values of 5.6 and 13.8 µM than the positive control minocycline (Mino, IC50 = 22.9 µM). The corresponding results of western blot analysis and qRT-PCR revealed that compound 3 can significantly inhibit the inducible nitric oxide synthase (iNOS) and cyclooxygenase 2 (COX-2) protein expressions, mRNA levels of pro-inflammatory cytokins of tumor necrosis factor-α (TNF-α), interleukin 6 (IL-6) and interleukin 1ß (IL-1ß). The underlying mechanism by which compound 3 exerted anti-neuroinflammatory effects was investigated by western blot and immunofluorescence assay, which suggested compound 3 inhibited LPS induced neuroinflammation via the suppression of toll-like receptor 4 (TLR4) dependent Signal Transducer and Activator of Transcription 3 (Stat3) and mitogen-activated protein kinase (MAPK) signaling pathways, and the activation of Heme Oxygenase-1 (HO-1) mediated signals.


Assuntos
Diterpenos Clerodânicos , Tinospora , Diterpenos Clerodânicos/farmacologia , Lipopolissacarídeos/farmacologia , Anti-Inflamatórios/farmacologia , Western Blotting
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