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1.
Adv Sci (Weinh) ; : e2307185, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38958448

RESUMO

Motor learning (ML), which plays a fundamental role in growth and physical rehabilitation, involves different stages of learning and memory processes through different brain regions. However, the neural mechanisms that underlie ML are not sufficiently understood. Here, a previously unreported neuronal projection from the dorsal hippocampus (dHPC) to the zona incerta (ZI) involved in the regulation of ML behaviors is identified. Using recombinant adeno-associated virus, the projections to the ZI are surprisingly identified as originating from the dorsal dentate gyrus (DG) and CA1 subregions of the dHPC. Furthermore, projection-specific chemogenetic and optogenetic manipulation reveals that the projections from the dorsal CA1 to the ZI play key roles in the acquisition and consolidation of ML behaviors, whereas the projections from the dorsal DG to the ZI mediate the retrieval/retention of ML behaviors. The results reveal new projections from the dorsal DG and dorsal CA1 to the ZI involved in the regulation of ML and provide insight into the stages over which this regulation occurs.

2.
ChemSusChem ; : e202400900, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38994916

RESUMO

Finding suitable bifunctional catalysts for industrial hydrogen production is the key to fully building a hydrogen energy society. Here we report a modulation of the surface morphology of electrodeposited CoP to form hydrangea-like Cobalt-Iron bimetallic phosphide (B-CoFeP@CoP) via ion-exchange and NaBH4-assisted methods. This catalyst exhibited excellent bifunctional catalytic capability at high current densities, achieving a current density of 500 mA cm-2 at a small overpotential (387 mV for OER and 252 mV for HER). When assembled into an OWS electrolyzer, this catalyst showed a fairly low cell voltage (≈1.88 V) at 500 mA cm-2 current density.,Furthermore, B-CoFeP@CoP shows ceaseless durability over 120 h in both freshwater and seawater with almost no change in the cell voltage. A combined experimental and theoretical study identified that the unique hydrangea-like structure provided a larger electrochemically active surface area and more effective active sites. Further analysis indicates that during the OER process, phosphides ensure that bimetallic active sites adsorb more OOH * intermediates and further DFT calculations showed that B-Fe2P and B-Co2P acted as active centers for dissociation of H2O and desorption of H2, respectively, to synergistically catalyze the HER process.

3.
Nat Commun ; 15(1): 5970, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39043666

RESUMO

Vacuolar protein sorting 35 (VPS35), the core component of the retromer complex which regulates endosomal trafficking, is genetically linked with Parkinson's disease (PD). Impaired vision is a common non-motor manifestation of PD. Here, we show mouse retinas with VPS35-deficient rods exhibit synapse loss and visual deficit, followed by progressive degeneration concomitant with the emergence of Lewy body-like inclusions and phospho-α-synuclein (P-αSyn) aggregation. Ultrastructural analyses reveal VPS35-deficient rods accumulate aggregates in late endosomes, deposited as lipofuscins bound to P-αSyn. Mechanistically, we uncover a protein network of VPS35 and its interaction with HSC70. VPS35 deficiency promotes sequestration of HSC70 and P-αSyn aggregation in late endosomes. Microglia which engulf lipofuscins and P-αSyn aggregates are activated, displaying autofluorescence, observed as bright dots in fundus imaging of live animals, coinciding with pathology onset and progression. The Rod∆Vps35 mouse line is a valuable tool for further mechanistic investigation of αSyn lesions and retinal degenerative diseases.


Assuntos
Degeneração Retiniana , Proteínas de Transporte Vesicular , alfa-Sinucleína , Animais , alfa-Sinucleína/metabolismo , alfa-Sinucleína/genética , Proteínas de Transporte Vesicular/metabolismo , Proteínas de Transporte Vesicular/genética , Camundongos , Degeneração Retiniana/genética , Degeneração Retiniana/metabolismo , Degeneração Retiniana/patologia , Células Fotorreceptoras Retinianas Bastonetes/metabolismo , Células Fotorreceptoras Retinianas Bastonetes/patologia , Endossomos/metabolismo , Microglia/metabolismo , Microglia/patologia , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia , Retina/metabolismo , Retina/patologia , Camundongos Knockout , Modelos Animais de Doenças , Humanos , Sinapses/metabolismo , Sinapses/patologia , Masculino
4.
Front Neurosci ; 18: 1423389, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39035776

RESUMO

Objective: Patients with temporal lobe epilepsy (TLE) often exhibit neurocognitive disorders; however, we still know very little about the pathogenesis of cognitive impairment in patients with TLE. Therefore, our aim is to detect changes in the structural connectivity networks (SCN) of patients with TLE. Methods: Thirty-five patients with TLE were compared with 47 normal controls (NC) matched according to age, gender, handedness, and education level. All subjects underwent thin-slice T1WI scanning of the brain using a 3.0 T MRI. Then, a large-scale structural covariance network was constructed based on the gray matter volume extracted from the structural MRI. Graph theory was then used to determine the topological changes in the structural covariance network of TLE patients. Results: Although small-world networks were retained, the structural covariance network of TLE patients exhibited topological irregularities in regular architecture as evidenced by an increase in the small world properties (p < 0.001), normalized clustering coefficient (p < 0.001), and a decrease in the transfer coefficient (p < 0.001) compared with the NC group. Locally, TLE patients showed a decrease in nodal betweenness and degree in the left lingual gyrus, right middle occipital gyrus and right thalamus compared with the NC group (p < 0.05, uncorrected). The degree of structural networks in both TLE (Temporal Lobe Epilepsy) and control groups was distributed exponentially in truncated power law. In addition, the stability of random faults in the structural covariance network of TLE patients was stronger (p = 0.01), but its fault tolerance was lower (p = 0.03). Conclusion: The objective of this study is to investigate the potential neurobiological mechanisms associated with temporal lobe epilepsy through graph theoretical analysis, and to examine the topological characteristics and robustness of gray matter structural networks at the network level.

5.
Materials (Basel) ; 17(13)2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38998440

RESUMO

Cerium-based materials (CeO2-x) are of significant interest in the development of vacancy-modulated resistive switching (RS) memory devices. However, the influence of grain boundaries on the performance of memristors is very limited. To fill this gap, this study explores the influence of grain boundaries in cerium-based thin film resistive random-access memory (RRAM) devices. Sm0.2Ce0.8O2-x (SDC20) thin films were deposited on (100)-oriented Nb-doped SrTiO3 (NSTO) and (110)-oriented NSTO substrates using pulsed laser deposition (PLD). Devices constructed with a Pt/SDC20/NSTO structure exhibited reversible and stable bipolar resistive switching (RS) behavior. The differences in conduction mechanisms between single-crystal and polycrystalline devices were confirmed, with single-crystal devices displaying a larger resistance window and higher stability. Combining the results of XPS and I-V curve fitting, it was confirmed that defects near the grain boundaries in the SDC-based memristors capture electrons, thereby affecting the overall performance of the RRAM devices.

6.
Eur J Med Chem ; 276: 116670, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-39018922

RESUMO

Development of resistance to therapy-induced cell death is a major hurdle in the effective treatment of advanced solid tumors. Erastin and RSL3 were originally found to induce synthetic lethality by induction of a novel form of cell death termed ferroptosis. Emerging evidence suggests that ferroptosis inducers enhance chemosensitivity of classic therapeutic agents by triggering ferroptotic cell death. In this study we evaluated the effects of erastin and RSL3 on the resistance of docetaxel, doxorubicin, and cisplatin, and revealed a mechanism whereby these ferroptosis inducers augment docetaxel efficacy in non-small cell lung cancer by regulating redox signaling to promote ferroptosis. Transcriptome analysis revealed that combination treatment modulated not only p53 signaling pathway but also immune responses and several signaling pathways including MAPK, NF-κB and PI3K/Akt. Considering that glutathione peroxidase 4 (GPX4) serves as the main effector to protect cells from ferroptosis, this study identified three novel non-covalent GPX4 inhibitors with the aid of pharmacophore-based virtual screening. The new ferroptosis-inducing compounds synergized with docetaxel to increase the cytotoxicity by promoting ferroptotic cell death in docetaxel-resistant A549/DTX cells. Collectively, the induction of ferroptosis contributed to docetaxel-induced cytotoxic effects and overcame drug resistance in A549/DTX cells. Ferroptosis has a great potential to become a new approach to attenuate resistance to some classic therapeutic drugs in cancer patients.

7.
J Neurosci Methods ; 409: 110217, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38964477

RESUMO

BACKGROUND: Parkinson's patients have significant autonomic dysfunction, early detect the disorder is a major challenge. To assess the autonomic function in the rat model of rotenone induced Parkinson's disease (PD), Blood pressure and ECG signal acquisition are very important. NEW METHOD: We used telemetry to record the electrocardiogram and blood pressure signals from awake rats, with linear and nonlinear analysis techniques calculate the heart rate variability (HRV) and blood pressure variability (BPV). we applied nonlinear analysis methods like sample entropy and detrended fluctuation analysis to analyze blood pressure signals. Particularly, this is the first attempt to apply nonlinear analysis to the blood pressure evaluate in rotenone induced PD model rat. RESULTS: HRV in the time and frequency domains indicated sympathetic-parasympathetic imbalance in PD model rats. Linear BPV analysis didn't reflect changes in vascular function and blood pressure regulation in PD model rats. Nonlinear analysis revealed differences in BPV, with lower sample entropy results and increased detrended fluctuation analysis results in the PD group rats. COMPARISON WITH EXISTING METHODS AND CONCLUSIONS: our experiments demonstrate the ability to evaluate autonomic dysfunction in models of Parkinson's disease by combining the analysis of BPV with HRV, consistent with autonomic impairment in PD patients. Nonlinear analysis by blood pressure signal may help in early detection of the PD. It indicates that the fluctuation of blood pressure in the rats in the rotenone model group tends to be regular and predictable, contributes to understand the PD pathophysiological mechanisms and to find strategies for early diagnosis.

8.
Talanta ; 279: 126578, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39032458

RESUMO

Accurate detection of ascorbic acid (AA) plays a significant role in food and human physiological processes. Herein, a three-dimensional flexible leaf-like nitrogen-doped hierarchical carbon nanoarrays with high-density carbon nanotube "tentacle" architecture (NC/CNT-Co), which possesses high specific surface area, plenty of active defect sites, and various pore size distributions, was synthesized by the pyrolysis of zeolitic imidazolate framework (ZIF(Co)), while g-C3N4 acted as carbon source and heteroatom doping agent. Benefiting from its unique structure and surface properties, a selective and highly sensitive AA sensor was developed using this material. Compared to powder materials, NC/CNT-Co modified CF (CF@NC/CNT-Co) which don't be extra decorated, exhibits lower detection limit (1 µM), a wider linear range (20-1400 µM), and better stability, showing higher performance in electrocatalysis and detection of AA. Furthermore, CF@NC/CNT-Co also demonstrates high resistance to interference and fouling in AA detection. Particularly, the prepared CF@NC/CNT-Co electrode could determine AA in beverage samples with a recovery rate of 96.3-103.5 %. Therefore, the three-dimensional NC/CNT-Co hierarchical structure can be provided as an original electrode nanomaterial suitable for the selective and sensitive detection of AA, with a wide range of practical applications from food analysis to the pharmaceutical industry.

9.
Int J Nanomedicine ; 19: 5837-5858, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38887692

RESUMO

Purpose: Phototherapy, known for its high selectivity, few side effects, strong controllability, and synergistic enhancement of combined treatments, is widely used in treating diseases like cervical cancer. Methods: In this study, hollow mesoporous manganese dioxide was used as a carrier to construct positively charged, poly(allylamine hydrochloride)-modified nanoparticles (NPs). The NP was efficiently loaded with the photosensitizer indocyanine green (ICG) via the addition of hydrogen phosphate ions to produce a counterion aggregation effect. HeLa cell membrane encapsulation was performed to achieve the final M-HMnO2@ICG NP. In this structure, the HMnO2 carrier responsively degrades to release ICG in the tumor microenvironment, self-generates O2 for sensitization to ICG-mediated photodynamic therapy (PDT), and consumes GSH to expand the oxidative stress therapeutic effect [chemodynamic therapy (CDT) + PDT]. The ICG accumulated in tumor tissues exerts a synergistic PDT/photothermal therapy (PTT) effect through single laser irradiation, improving efficiency and reducing side effects. The cell membrane encapsulation increases nanomedicine accumulation in tumor tissues and confers an immune evasion ability. In addition, high local temperatures induced by PTT can enhance CDT. These properties of the NP enable full achievement of PTT/PDT/CDT and targeted effects. Results: Mn2+ can serve as a magnetic resonance imaging agent to guide therapy, and ICG can be used for photothermal and fluorescence imaging. After its intravenous injection, M-HMnO2@ICG accumulated effectively at mouse tumor sites; the optimal timing of in-vivo laser treatment could be verified by near-infrared fluorescence, magnetic resonance, and photothermal imaging. The M-HMnO2@ICG NPs had the best antitumor effects among treatment groups under near-infrared light conditions, and showed good biocompatibility. Conclusion: In this study, we designed a nano-biomimetic delivery system that improves hypoxia, responds to the tumor microenvironment, and efficiently loads ICG. It provides a new economical and convenient strategy for synergistic phototherapy and CDT for cervical cancer.


Assuntos
Verde de Indocianina , Compostos de Manganês , Imagem Multimodal , Nanopartículas , Fotoquimioterapia , Fármacos Fotossensibilizantes , Microambiente Tumoral , Neoplasias do Colo do Útero , Neoplasias do Colo do Útero/terapia , Neoplasias do Colo do Útero/diagnóstico por imagem , Neoplasias do Colo do Útero/tratamento farmacológico , Feminino , Microambiente Tumoral/efeitos dos fármacos , Humanos , Verde de Indocianina/química , Verde de Indocianina/farmacologia , Fotoquimioterapia/métodos , Animais , Células HeLa , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/química , Nanopartículas/química , Compostos de Manganês/química , Compostos de Manganês/farmacologia , Camundongos , Imagem Multimodal/métodos , Terapia Fototérmica/métodos , Óxidos/química , Óxidos/farmacologia , Camundongos Endogâmicos BALB C , Poliaminas/química , Poliaminas/farmacologia , Imageamento por Ressonância Magnética/métodos
10.
Int Wound J ; 21(6): e14940, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38888416

RESUMO

Bacterial infection is the most common complication in wound healing, highlighting an urgent need for the development of innovative antibacterial technologies and treatments to address the growing threats posed by bacterial infections. Black phosphorus nanosheets (BPNSs), as a promising two-dimensional nanomaterial, have been utilized in treating infected wounds. However, BP's limited stability restricts its application. In this study, we enhance BP's stability and its antibacterial properties by anchoring gallium ions (Ga3+) onto BP's surface, creating a novel antibacterial platform. This modification reduces BP's electron density and enhances its antibacterial capabilities through a synergistic effect. Under near-infrared (NIR) irradiation, the BP/Ga3+ combination exerts antibacterial effects via photothermal therapy (PTT) and photodynamic therapy (PDT), while also releasing Ga3+. The Ga3+ employ a 'Trojan horse strategy' to disrupt iron metabolism, significantly boosting the antibacterial efficacy of the complex. This innovative material offers a viable alternative to antibiotics and holds significant promise for treating infected wounds and aiding skin reconstruction.


Assuntos
Antibacterianos , Gálio , Fósforo , Cicatrização , Gálio/farmacologia , Gálio/uso terapêutico , Cicatrização/efeitos dos fármacos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Humanos , Animais , Nanoestruturas/uso terapêutico , Infecção dos Ferimentos/tratamento farmacológico , Fotoquimioterapia/métodos , Infecções Bacterianas/tratamento farmacológico , Camundongos , Terapia Fototérmica/métodos
11.
Molecules ; 29(11)2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38893498

RESUMO

Due to the high content of impurities such as proteins in tamarind seed polysaccharide (TSP), they must be separated and purified before it can be used. TSP can disperse in cold water, but a solution can only be obtained by heating the mixture. Therefore, it is important to understand the dispersion and dissolution process of TSP at different temperatures to expand the application of TSP. In this study, pasting behavior and rheological properties as a function of temperature were characterized in comparison with potato starch (PS), and their relationship with TSP molecular features and microstructure was revealed. Pasting behavior showed that TSP had higher peak viscosity and stronger thermal stability than PS. Rheological properties exhibited that G' and G'' of TSP gradually increased with the increase in temperature, without exhibiting typical starch gelatinization behavior. The crystalline or amorphous structure of TSP and starch was disrupted under different temperature treatment conditions. The SEM results show that TSP particles directly transformed into fragments with the temperature increase, while PS granules first expanded and then broken down into fragments. Therefore, TSP and PS underwent different dispersion mechanisms during the dissolution process: As the temperature gradually increased, TSP possibly underwent a straightforward dispersion and was then dissolved in aqueous solution, while PS granules initially expanded, followed by disintegration and dispersion.


Assuntos
Polissacarídeos , Reologia , Sementes , Amido , Tamarindus , Temperatura , Tamarindus/química , Polissacarídeos/química , Sementes/química , Viscosidade , Amido/química , Fenômenos Químicos
12.
J Colloid Interface Sci ; 672: 574-588, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-38852358

RESUMO

In this paper, microgels with uniform particle size were prepared by physically cross-linking the hydrophobically modified chitosan (h-CS) with sodium phytate (SP). The effects of cross-linking density on the interfacial adsorption kinetics, viscoelasticity, stress relaxation, and micorheological properties of the hydrophobically modified chitosan microgels (h-CSMs) at the oil-water interface were extensively investigated by the dilatational rheology, compressional rheology, and particle tracing microrheology. The results were correlated with the particle size, morphology, and elasticity of the microgels characterized by dynamic light scattering and atomic force microscopy. It was found that with the increase of cross-linking density, the h-CSMs changed from a polymer-like state to ultra-soft fussy spheres with higher elastic modulus. The compression isotherms demonstrated multi-stage increase caused by the interaction between the shells and that between the cores of the microgels successively. As the increase of cross-linking density, the h-CSMs diffused slower to the oil-water interface, but demonstrating faster permeation adsorption and rearrangement at the oil-water interface, finally forming interfacial layers of higher viscoelastic modulus due to the core-core interaction. Both the initial tension relaxation and the microgel rearrangement after interface expansion became faster as the microgel elasticity increased. The interfacial microrheology demonstrated dynamic caging effect caused by neighboring microgels. This article provides a more comprehensive understanding of the behaviors of polysaccharide microgels at the oil-water interface.

13.
Mol Med ; 30(1): 93, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38898476

RESUMO

BACKGROUND: The epithelial-mesenchymal transition (EMT) of human bronchial epithelial cells (HBECs) is essential for airway remodeling during asthma. Wnt5a has been implicated in various lung diseases, while its role in the EMT of HBECs during asthma is yet to be determined. This study sought to define whether Wnt5a initiated EMT, leading to airway remodeling through the induction of autophagy in HBECs. METHODS: Microarray analysis was used to investigate the expression change of WNT5A in asthma patients. In parallel, EMT models were induced using 16HBE cells by exposing them to house dust mites (HDM) or interleukin-4 (IL-4), and then the expression of Wnt5a was observed. Using in vitro gain- and loss-of-function approaches via Wnt5a mimic peptide FOXY5 and Wnt5a inhibitor BOX5, the alterations in the expression of the epithelial marker E-cadherin and the mesenchymal marker protein were observed. Mechanistically, the Ca2+/CaMKII signaling pathway and autophagy were evaluated. An autophagy inhibitor 3-MA was used to examine Wnt5a in the regulation of autophagy during EMT. Furthermore, we used a CaMKII inhibitor KN-93 to determine whether Wnt5a induced autophagy overactivation and EMT via the Ca2+/CaMKII signaling pathway. RESULTS: Asthma patients exhibited a significant increase in the gene expression of WNT5A compared to the healthy control. Upon HDM and IL-4 treatments, we observed that Wnt5a gene and protein expression levels were significantly increased in 16HBE cells. Interestingly, Wnt5a mimic peptide FOXY5 significantly inhibited E-cadherin and upregulated α-SMA, Collagen I, and autophagy marker proteins (Beclin1 and LC3-II). Rhodamine-phalloidin staining showed that FOXY5 resulted in a rearrangement of the cytoskeleton and an increase in the quantity of stress fibers in 16HBE cells. Importantly, blocking Wnt5a with BOX5 significantly inhibited autophagy and EMT induced by IL-4 in 16HBE cells. Mechanistically, autophagy inhibitor 3-MA and CaMKII inhibitor KN-93 reduced the EMT of 16HBE cells caused by FOXY5, as well as the increase in stress fibers, cell adhesion, and autophagy. CONCLUSION: This study illustrates a new link in the Wnt5a-Ca2+/CaMKII-autophagy axis to triggering airway remodeling. Our findings may provide novel strategies for the treatment of EMT-related diseases.


Assuntos
Asma , Autofagia , Células Epiteliais , Transição Epitelial-Mesenquimal , Proteína Wnt-5a , Humanos , Proteína Wnt-5a/metabolismo , Proteína Wnt-5a/genética , Asma/metabolismo , Asma/patologia , Asma/genética , Células Epiteliais/metabolismo , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Brônquios/metabolismo , Brônquios/patologia , Masculino , Linhagem Celular , Feminino , Pessoa de Meia-Idade , Transdução de Sinais , Adulto
14.
Nanoscale ; 16(25): 12237-12247, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38847457

RESUMO

In the field of hydrogen production, MoS2 demonstrates good catalytic properties for the hydrogen evolution reaction (HER) which improve when doped with metal cations. However, while the role of sulfur atoms as active sites in the HER is largely reported, the role of metal atoms (i.e. molybdenum or the dopant cations) has yet to be studied in depth. To understand the role of the metal dopant, we study MoS2 thin films doped with Co and Mn ions. We identify the contribution of the electronic bands of the Mn and Co dopants to the integral valence band of the material using in situ resonant photoemission measurements. We demonstrate that Mn and Co dopants act differently: Mn doping favors the shift of the S-Mo hybridized band towards the Fermi level, while in the case of Co doping it is the less hybridized Co band that shifts closer to the Fermi level. Doping with Mn increases the effectiveness of S as the active site, thus improving the HER, while doping with Co introduces the metallic site of Co as the active site, which is less effective in improving HER properties. We therefore clarify the role of the dopant cation in the electronic structure determining the active site for hydrogen adsorption/desorption. Our results pave the way for the design of efficient materials for hydrogen production via the doping route, which can be extended to different catalytic reactions in the field of energy applications.

15.
Sci Rep ; 14(1): 13670, 2024 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-38871968

RESUMO

Cervical cancer, one of the most common gynecological cancers, is primarily caused by human papillomavirus (HPV) infection. The development of resistance to chemotherapy is a significant hurdle in treatment. In this study, we investigated the mechanisms underlying chemoresistance in cervical cancer by focusing on the roles of glycogen metabolism and the pentose phosphate pathway (PPP). We employed the cervical cancer cell lines HCC94 and CaSki by manipulating the expression of key enzymes PCK1, PYGL, and GYS1, which are involved in glycogen metabolism, through siRNA transfection. Our analysis included measuring glycogen levels, intermediates of PPP, NADPH/NADP+ ratio, and the ability of cells to clear reactive oxygen species (ROS) using biochemical assays and liquid chromatography-mass spectrometry (LC-MS). Furthermore, we assessed chemoresistance by evaluating cell viability and tumor growth in NSG mice. Our findings revealed that in drug-resistant tumor stem cells, the enzyme PCK1 enhances the phosphorylation of PYGL, leading to increased glycogen breakdown. This process shifts glucose metabolism towards PPP, generating NADPH. This, in turn, facilitates ROS clearance, promotes cell survival, and contributes to the development of chemoresistance. These insights suggest that targeting aberrant glycogen metabolism or PPP could be a promising strategy for overcoming chemoresistance in cervical cancer. Understanding these molecular mechanisms opens new avenues for the development of more effective treatments for this challenging malignancy.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Glicogênio , Células-Tronco Neoplásicas , Fosfoenolpiruvato Carboxiquinase (GTP) , Espécies Reativas de Oxigênio , Neoplasias do Colo do Útero , Humanos , Feminino , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/tratamento farmacológico , Neoplasias do Colo do Útero/patologia , Espécies Reativas de Oxigênio/metabolismo , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/efeitos dos fármacos , Animais , Camundongos , Linhagem Celular Tumoral , Fosfoenolpiruvato Carboxiquinase (GTP)/metabolismo , Fosfoenolpiruvato Carboxiquinase (GTP)/genética , Glicogênio/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Glicogenólise , Via de Pentose Fosfato/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos
16.
Histol Histopathol ; : 18764, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38835215

RESUMO

BACKGROUND: Hyperglycemia is a risk factor for impaired renal function, including cellular metabolic disturbance, apoptosis, inflammation, and histologic lesion. This study aims to investigate the potential therapeutic targeting of cyclin-dependent kinase 5 (Cdk5) in hyperglycemia-induced podocyte dysfunction and renal damage. METHODS: Cell viability and apoptosis of podocytes were assessed through CCK-8 and TUNEL staining, respectively, following exposure to normal glucose (NG; 5 mM), high glucose (HG; 30 mM), or treatment with Cdk5 inhibitors (trans-resveratrol, myricetin, salvianolic acid A, and BML-259). Diabetic mice were established by intraperitoneal injection of freshly streptozotocin (STZ), which was given at a dose of 35 mg/kg in five successive injections. Additionally, histochemical staining was employed to evaluate the morphologic lesion of the kidney. RESULTS: Cdk5 was found to be activated by HG stimulation both in vitro and in vivo. Notably, the inhibition of Cdk5 effectively mitigated the podocyte dysfunction induced by HG, including growth inhibition, membrane damage, and apoptosis. The compounds Trans-resveratrol, myricetin, salvianolic acid A, and BML-259 exhibited low binding energy values of -8.032 kcal/mol, -8.693 kcal/mol, -8.743 kcal/mol, and -10.952 kcal/mol, respectively, indicating strong and stable binding affinity between these candidates and Cdk5. The results of in vivo experimental analysis demonstrate that Cdk5 inhibitors, namely trans-resveratrol, myricetin, salvianolic acid A, and BML-259, confer protection against tubular and glomerular lesions induced by hyperglycemia. CONCLUSION: Both myricetin and BML-259 exhibit comparable protective effects on renal injury by inhibiting Cdk5.

17.
Ying Yong Sheng Tai Xue Bao ; 35(4): 1025-1032, 2024 Apr 18.
Artigo em Chinês | MEDLINE | ID: mdl-38884237

RESUMO

In this study, we explored the thickness influence of undecomposed litter layer and semi-decomposed litter layer on the natural regeneration in an artificial pure forest of Larix principis-rupprechtii in the forest area of Guandi Mountain. We divided the litter into an undecomposed layer and a semi-decomposed layer, which was further divided into eight groups based on the thickness. The results showed that when the thickness of undecomposed layer was 0.32-0.83 cm, and that of semi-decomposed layer was 0.18-0.89 cm, the regeneration index was larger (≥0.15), and the regeneration was better. When the thickness of undecomposed layer was more than 1.1 cm and that of semi-decomposed layer was more than 0.5 cm, the regeneration index was smaller (≤0.07), and the rege-neration of understory was worse. Results of redundancy analysis showed that the undecomposed layer thickness of litter had a high and stable explanatory ability for natural regeneration, with a contribution rate of 38.7%, while the semi-decomposed layer thickness had no significant effect on natural regeneration. Structural equation modeling revealed that the thickness of undecomposed layer of litter increased the mechanical resistance to seed germination which had a negative direct effect on natural regeneration (-0.617), and a positive indirect effect on natural rege-neration by influencing the content of alkali-hydrolyzed nitrogen and available phosphorus (+0.178). The combined effects (-0.439) showed an inhibitory effect on the natural regeneration. In conclusion, the thickness of undecomposed layer of litter under L. principis-rupprechtii was most closely related to natural regeneration, and the thickness of semi-decomposed layer had a minimal effect on natural regeneration.


Assuntos
Larix , Larix/crescimento & desenvolvimento , China , Folhas de Planta/crescimento & desenvolvimento , Conservação dos Recursos Naturais , Ecossistema , Florestas , Solo/química
18.
J Clin Epidemiol ; 173: 111429, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38880436

RESUMO

OBJECTIVES: Patient and public versions of guidelines (PVGs) have gradually gained wide recognition and attention from the public and the society due to their scientific, professional, and authoritative characteristics. This study aims to survey the awareness and knowledge of PVGs among stakeholders in China. STUDY DESIGN AND SETTING: This was a cross-sectional survey among stakeholders (guideline developers, clinicians, journal editors, patients, and the public) in China. We self-designed the questionnaire and distributed it through the Questionnaire Star platform. The primary outcomes were awareness of PVGs and opinions about the development methodology, writing, dissemination, and implementation of PVGs. The Kruskal-Wallis H test and post hoc multiple comparison tests were used to compare the levels of awareness of PVGs between different subgroups of respondents. RESULTS: A total of 1319 valid questionnaires were collected: 722 from guideline developers, 136 from clinicians, 83 from journal editors, 284 from patients, and 94 from members of the public. Of all respondents, 253 (19.2%) had not heard of PVGs, 349 (26.5%) had heard of PVGs but had no further knowledge, 475 (36.0%) had some knowledge of PVGs, and 242 (18.3%) were familiar with or had participated in the development of PVGs. Guideline developers, clinicians, and journal editors had higher awareness than patients and the public. Higher education and older age also correlated with higher awareness of PVGs. More than half (52.9%) of guideline developers considered that both rewriting of the source guidelines and direct development as independent documents were appropriate methods for developing PVGs. The survey respondents agreed that clinicians (97.3%), guideline methodologists (76.6%), representatives of patients and the public (74.5%), and medical editors or writers (63.4%) should participate in the development of PVGs. More than 80% of the respondents agreed that the quality of evidence and strength of recommendations should be presented; however, there was no consensus in the form of presentation. CONCLUSIONS: The level of awareness of PVGs among stakeholders in China is relatively low and differs between different stakeholder groups, but the majority of key stakeholders have a positive attitude toward PVGs. The collection of the perspectives and opinions on the development methods, writing, dissemination, and implementation provides a key reference and basis for the future optimization and improvement of PVGs development.

19.
Nat Commun ; 15(1): 5239, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38937448

RESUMO

Tuberculosis remains a large global disease burden for which treatment regimens are protracted and monitoring of disease activity difficult. Existing detection methods rely almost exclusively on bacterial culture from sputum which limits sampling to organisms on the pulmonary surface. Advances in monitoring tuberculous lesions have utilized the common glucoside [18F]FDG, yet lack specificity to the causative pathogen Mycobacterium tuberculosis (Mtb) and so do not directly correlate with pathogen viability. Here we show that a close mimic that is also positron-emitting of the non-mammalian Mtb disaccharide trehalose - 2-[18F]fluoro-2-deoxytrehalose ([18F]FDT) - is a mechanism-based reporter of Mycobacteria-selective enzyme activity in vivo. Use of [18F]FDT in the imaging of Mtb in diverse models of disease, including non-human primates, successfully co-opts Mtb-mediated processing of trehalose to allow the specific imaging of TB-associated lesions and to monitor the effects of treatment. A pyrogen-free, direct enzyme-catalyzed process for its radiochemical synthesis allows the ready production of [18F]FDT from the most globally-abundant organic 18F-containing molecule, [18F]FDG. The full, pre-clinical validation of both production method and [18F]FDT now creates a new, bacterium-selective candidate for clinical evaluation. We anticipate that this distributable technology to generate clinical-grade [18F]FDT directly from the widely-available clinical reagent [18F]FDG, without need for either custom-made radioisotope generation or specialist chemical methods and/or facilities, could now usher in global, democratized access to a TB-specific PET tracer.


Assuntos
Mycobacterium tuberculosis , Tomografia por Emissão de Pósitrons , Trealose , Tuberculose , Animais , Mycobacterium tuberculosis/metabolismo , Tomografia por Emissão de Pósitrons/métodos , Trealose/metabolismo , Tuberculose/diagnóstico por imagem , Tuberculose/microbiologia , Tuberculose/metabolismo , Humanos , Camundongos , Radioisótopos de Flúor , Fluordesoxiglucose F18/metabolismo , Fluordesoxiglucose F18/química , Compostos Radiofarmacêuticos/metabolismo , Modelos Animais de Doenças , Feminino
20.
Fundam Res ; 4(1): 178-187, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38933846

RESUMO

Theranostic agents that can be sensitively and specifically activated by the tumor microenvironment (TME) have recently attracted considerable attention. In this study, TME-activatable 3,3',5,5'-tetramethylbenzidine (TMB)-copper peroxide (CuO2)@poly(lactic-co-glycolic acid) (PLGA)@red blood cell membrane (RBCM) (TCPR) nanoparticles (NPs) for second near-infrared photoacoustic imaging-guided tumor-specific photothermal therapy were developed by co-loading CuO2 NPs and TMB into PLGA camouflaged by RBCMs. As an efficient H2O2 supplier, once exposed to a proton-rich TME, CuO2 NPs can generate H2O2 and Cu2+, which are further reduced to Cu+ by endogenous glutathione. Subsequently, the Cu+-mediated Fenton-like reaction produces cytotoxic ·OH to kill the cancer cells and induce TMB-mediated photoacoustic and photothermal effects. Combined with the RBCM modification-prolonged blood circulation, TCPR NPs display excellent specificity and efficiency in suppressing tumor growth, paving the way for more accurate, safe, and efficient cancer theranostics.

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