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1.
Heliyon ; 10(8): e28863, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38638974

RESUMEN

Background: As a scaffold protein, calcium/calmodulin-dependent serine protein kinase (CASK) has been extensively studied in a variety of tissues throughout the body. The Cask gene is ubiquitous in several tissues, such as the neurons, islets, heart, kidneys and sperm, and is mostly localised in the cytoplasm adjacent to the basement membrane. CASK binds to a variety of proteins through its domains to exerting its biological activity. Scope of review: Here, we discuss the role of CASK in multiple tissues throughout the body. The role of different CASK domains in regulating neuronal development, neurotransmitter release and synaptic vesicle secretion was emphasised; the regulatory mechanism of CASK on the function of pancreatic islet ß cells was analysed; the role of CASK in cardiac physiology, kidney and sperm development was discussed; and the role of CASK in different tumours was compared. Finally, we clarify the importance of the Cask gene in the body, and how deletion or mutation of the Cask gene can have adverse consequences. Major conclusions: CASK is a conserved gene with similar roles in various tissues. The function of the Cask gene in the nervous system is mainly involved in the development of the nervous system and the release of neurotransmitters. In the endocrine system, an involvement of CASK has been reported in the process of insulin vesicle transport. CASK is also involved in cardiomyocyte ion channel regulation, kidney and sperm development, and tumour proliferation. CASK is an indispensable gene for the whole body, and CASK mutations can cause foetal malformations or death at birth. In this review, we summarise the biological functions and pathological mechanisms of CASK in various systems, thereby providing a basis for further in-depth studies of CASK functions.

2.
Chemphyschem ; 25(7): e202400213, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38488296

RESUMEN

The front cover artwork is provided by Rui Cao's group at Shaanxi Normal University. The image shows the design of Co-porphyrin-engineered phenolic resins with intramolecular phenolic hydroxyl groups to facilitate proton and electron transfers for efficient oxygen electrocatalysis, which is bioinspired by cytochrome c oxidases, and shows the excellent performance of Zn-air batteries assembled with the hybrid material. Read the full text of the Research Article at 10.1002/cphc.202400017.

3.
Knee ; 48: 83-93, 2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-38555717

RESUMEN

OBJECTIVE: To investigate the effects of astaxanthin (AST) on mouse osteoarthritis (OA) and lipopolysaccharide (LPS)-induced ATDC5 cell damage and to explore whether SIRT1 protein plays a role. METHODS: In this study, some mouse OA models were constructed by anterior cruciate ligament transection (ACLT). Imaging, molecular biology and histopathology methods were used to study the effect of AST administration on traumatic OA in mice. In addition, LPS was used to stimulate ATDC5 cells to mimic the inflammatory response of OA. The effects of AST on the cell activity, inflammatory cytokines, matrix metalloproteinases and collagen type II levels were studied by CCK8 activity assay, reverse transcription polymerase chain reaction and protein imprinting. The role of SIRT1 protein was also detected. RESULTS: In the mouse OA model, the articular surface collapsed, the articular cartilage thickness and cartilage matrix protein abundance were significantly decreased, while the expression of inflammatory cytokines and matrix metalloproteinases was increased; but AST treatment reversed these effects. Meanwhile, AST pretreatment could partially reverse LPS-induced ATDC5 cell damage and upregulate SIRT1 expression, but this protective effect of AST was attenuated by concurrent administration of the SIRT1 inhibitor Ex527. CONCLUSION: AST can protect against the early stages of OA by affecting SIRT1 signalling, suggesting that AST might be a potential therapeutic agent for OA treatment.

4.
Angew Chem Int Ed Engl ; 63(13): e202401074, 2024 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-38311965

RESUMEN

The electronic structure of metal complexes plays key roles in determining their catalytic features. However, controlling electronic structures to regulate reaction mechanisms is of fundamental interest but has been rarely presented. Herein, we report electronic tuning of Cu porphyrins to switch pathways of the hydrogen evolution reaction (HER). Through controllable and regioselective ß-oxidation of Cu porphyrin 1, we synthesized analogues 2-4 with one or two ß-lactone groups in either a cis or trans configuration. Complexes 1-4 have the same Cu-N4 core site but different electronic structures. Although ß-oxidation led to large anodic shifts of reductions, 1-4 displayed similar HER activities in terms of close overpotentials. With electrochemical, chemical and theoretical results, we show that the catalytically active species switches from a CuI species for 1 to a Cu0 species for 4. This work is thus significant to present mechanism-controllable HER via electronic tuning of catalysts.

5.
Water Res ; 252: 121184, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38377699

RESUMEN

Singlet oxygen (1O2) is extensively employed in the fields of chemical, biomedical and environmental. However, it is still a challenge to produce high- concentration 1O2 by dioxygen activation. Herein, a system of carbon-supported rare-earth oxide nanocluster and single atom catalysts (named as RE2O3/RE-C, RE=La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Sc and Y) with similar morphology, structure, and physicochemical characteristic are constructed to activate dissolved oxygen (DO) to enhance 1O2 production. The catalytic activity trends and mechanisms are revealed experimentally and are also proven by theoretical analyses and calculations. The 1O2 generation activity trend is Gd2O3/Gd-C>Er2O3/Er-C>Sm2O3/Sm-C>pristine carbon (C). More than 95.0% of common antibiotics (ciprofloxacin, ofloxacin, norfloxacin and carbamazepine) can be removed in 60 min by Gd2O3/Gd-C. Density functional theory calculations indicate that Gd2O3 nanoclusters and Gd single atoms exhibit the moderate adsorption energy of ·O2- to enhance 1O2 production. This study offers a universal strategy to enhance 1O2 production in dioxygen activation for future application and reveals the natural essence of basic mechanisms of 1O2 production via rare-earth oxide nanoclusters and rare-earth single atoms.


Asunto(s)
Metales de Tierras Raras , Oxígeno Singlete , Óxidos/química , Oxígeno , Antibacterianos , Metales de Tierras Raras/análisis , Metales de Tierras Raras/química
6.
Chemphyschem ; 25(7): e202400017, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38319009

RESUMEN

Using functionalized supporting materials for the immobilization of molecular catalysts is an appealing strategy to improve the efficiency of molecular electrocatalysis. Herein, we report the covalent tethering of cobalt porphyrins on phenolic resins (PR) for improved electrocatalytic oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). A cobalt porphyrin bearing an alkyl bromide substituent was covalently tethered on phenolic resins, through the substitution reaction of alkyl bromides with phenolic hydroxyl groups, to afford molecule-engineered phenolic resins (Co-PR). The resulted Co-PR was efficient for electrocatalytic ORR and OER by displaying an ORR half-wave potential of E1/2=0.78 V versus RHE and an OER overpotential of 420 mV to get 10 mA/cm2 current density. We propose that the many residual phenolic hydroxyl groups on PR will surround the tethered Co porphyrin and play critical roles in facilitating proton and electron transfers. Importantly, Co-PR outperformed unmodified PR and PR loaded with Co porphyrins through simple physical adsorption (termed Co@PR). The zinc-air battery assembled using Co-PR displayed a performance comparable to that using Pt/C+Ir/C. This work is significant to present phenolic resins as a functionalized material to support molecular electrocatalysts and demonstrate the strategy to improve molecular electrocatalysis with the use of phenolic resin residues.

7.
J Am Chem Soc ; 146(5): 3545-3552, 2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38277257

RESUMEN

Atom-precise metal nanoclusters (NCs) with large bulk (nuclearity >60) are important species for insight into the embryonic phase of metal nanoparticles and their top-down etching synthesis. Herein, we report a metastable rod-shaped 70-nuclei copper-hydride NC, [Cl@Cu70H22(PhC≡C)29(CF3COO)16]2+ (Cu70), with Cl- as the template, in which the Cl@Cu59 kernel adopts a distinctive metal packing mode along the bipolar direction, and the protective ligand shell exhibits corresponding site differentiation. In terms of metal nuclearity, Cu70 is the largest alkynyl-stabilized Cu-hydride cluster to date. As a typical highly active intermediate, Cu70 could undergo a transformation into a series of robust modularly assembled Cu clusters (B-type Cu8, A-A-type Cu22, A-B-type Cu23, and A-B-A-type Cu38) upon etching by p-tert-butylthiacalix[4]arene (H4TC4A), which could not be achieved by "one-pot" synthetic methods. Notably, the patterns of A and B blocks in the Cu NCs could be effectively modulated by employing appropriate counterions and blockers, and the modular assembly mechanism was illustrated through comprehensive solution chemistry analysis using HR-ESI-MS. Furthermore, catalytic investigations reveal that Cu38 could serve as a highly efficient catalyst for the cycloaddition of propargylic amines with CO2 under mild conditions. This work not only enriched the family of high-nuclear copper-hydride NCs but also provided new insights into the growth mechanism of metal NCs.

8.
Angew Chem Int Ed Engl ; 62(51): e202312255, 2023 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-37921242

RESUMEN

In nature, cytochrome c oxidases catalyze the 4e- oxygen reduction reaction (ORR) at the heme/Cu site, in which CuI is used to assist O2 activation. Because of the thermodynamic barrier to generate CuI , synthetic Fe-porphyrin/Cu complexes usually show moderate electrocatalytic ORR activity. We herein report on a Co-corrole/Co complex 1-Co for energy-efficient electrocatalytic ORR. By hanging a CoII ion over Co corrole, 1-Co realizes electrocatalytic 4e- ORR with a half-wave potential of 0.89 V versus RHE, which is outstanding among corrole-based electrocatalysts. Notably, 1-Co outperforms Co corrole hanged with CuII or ZnII . We revealed that the hanging CoII ion can provide an electron to improve O2 binding thermodynamically and dynamically, a function represented by the biological CuI ion of the heme/Cu site. This work is significant to present a remarkable ORR electrocatalyst and to show the vital role of a second-sphere redox-active metal ion in promoting O2 binding and activation.

9.
Artículo en Inglés | MEDLINE | ID: mdl-37531312

RESUMEN

As an advanced technique in remote sensing, hyperspectral target detection (HTD) is widely concerned in civilian and military applications. However, the limitation of prior and heterogeneous backgrounds makes HTD models sensitive to data corruption under various interference from the environment. In this article, a novel united HTD framework based on the concept of transformer is proposed to extract HTD based on transformer via spectral-spatial similarity (HTD-TS 3 ) under weak supervision, which opens up more flexible ways to study HTD. For the first time, the transformer mechanism is introduced into the HTD task to extract spectral and spatial features in a unified optimization procedure. By modeling long-range dependence among spectra, it realizes spectral-spatial joint inference based on long-range context, which addresses the issues of insufficient utilization of spatial information. To provide samples for weakly supervised learning (WSL), the coarse sample selection and spectral sequence construction in an efficient way are proposed, which makes full use of limited prior information. Finally, an exponential constrained nonlinear function is adopted to acquire pixel-level prediction via combining discriminative spectral-spatial features and coarse spatial information. Experiments on real hyperspectral images (HSIs) captured by different sensors at various scenes verify the effectiveness and efficiency of HTD-TS 3 .

10.
Environ Sci Pollut Res Int ; 30(27): 70731-70741, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37155091

RESUMEN

Adsorption of vanadium from wastewater defends the environment from toxic ions and contributes to recover the valuable metal. However, it is still challenging for the separation of vanadium (V5+) and chromium (Cr6+) because of their similar properties. Herein, a kind of CeO2 nanorod containing oxygen vacancies is facilely synthesized which displays ultra-high selectivity of V5+ against various competitive ions (i.e., Fe, Mn, Cr, Ni, Cu, Zn, Ga, Cd, Ba, Pb, Mg, Be, and Co). Moreover, a large separation factor (SFV/Cr) of 114,169.14 for the selectivity of V5+ is achieved at the Cr6+/V5+ ratio of 80 with the trace amount of V5+ (~ 1 mg/L). The results show that the process of V5+ uptake is the monolayer homogeneous adsorption and is controlled by external and intraparticle diffusions. In addition, it also shows that V5+ is reduced to V3+ and V4+ and then formation of V-O complexation. This work offers a novel CeO2 nanorod material for efficient separation of V5+ and Cr6+ and also clarifies the mechanism of the V5+ adsorption on the CeO2 surface.


Asunto(s)
Vanadio , Contaminantes Químicos del Agua , Cromo/análisis , Iones , Aguas Residuales , Adsorción , Contaminantes Químicos del Agua/análisis
11.
Angew Chem Int Ed Engl ; 62(1): e202214449, 2023 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-36344440

RESUMEN

Synthesizing large-area free-standing covalent organic framework (COF) films is of vital importance for their applications but is still a big challenge. Herein, we reported the synthesis of large metalloporphyrin-based COF films and their applications for oxygen electrocatalysis. The reaction of meso-benzohydrazide-substituted metal porphyrins with tris-aldehyde linkers afforded free-standing COF films at the liquid-air interface. These films can be scaled up to 3000 cm2 area and display great mechanical stability and structural integrity. Importantly, the Co-porphyrin-based films are efficient for electrocatalytic O2 reduction and evolution reactions. A flexible, all-solid-state Zn-air battery was assembled using the films and showed high performance with a charge-discharge voltage gap of 0.88 V at 1 mA cm-2 and high stability under bent conditions (0° to 180°). This work thus presents a strategy to synthesize functionalized COF films with high quality for uses in flexible electronics.

12.
Clin Neurol Neurosurg ; 212: 107082, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34902752

RESUMEN

OBJECTIVE: To evaluate the curative efficacy by comparing perioperative characteristics and 1.5-year observational outcomes in 1-segment lumbar spondylolisthesis between traditional minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) and optimized Endoscopic TLIF techniques. METHODS: The study was a single-center, randomized controlled trial comparing two different treatment approaches for 1-segment lumbar spondylolisthesis. 102 patients treated by MIS-TLIF (48 cases) or Endo-TLIF (54 cases) were included from March 2018 to April 2019. Perioperative parameters and clinical outcomes were evaluated. Degree of slip were measured, and fusion rates were determined at 18 months after surgery. RESULTS: The Endo-TLIF group had similar return to work time and rate. Blood loss, left bed time, analgesic ratio were significantly less in Endo-TLIF group. The Endo-TLIF group had a significantly longer operative time. Significant postoperative reduction in %slip was showed in both groups. The VAS and ODI improved significantly in both groups after surgery. Significant decreases in low-back pain in Endo-TLIF group were found at postoperative day 1 and 3 months. The fusion rate in the two groups was similar. CONCLUSION: Endo-TLIF surgery with a C-shaped working tube and a visualization system may be regarded as an efficient alternative surgery for 1-segment lumbar spondylolisthesis. It is a safe and minimally invasive way to perform this surgery and has shown satisfactory clinical outcomes. TRIAL REGISTRATION: ChiCTR1800015197, 13 March 2018. TRIAL REGISTRY: Chinese Clinical Trial Registry. Registered 13 March 2018. http://www.chictr.org.cn/showproj.aspx?proj=25865.


Asunto(s)
Artroscopía , Vértebras Lumbares/cirugía , Evaluación de Resultado en la Atención de Salud , Fusión Vertebral , Espondilolistesis/cirugía , Anciano , Artroscopía/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Estudios Prospectivos , Fusión Vertebral/instrumentación , Fusión Vertebral/métodos
13.
Am J Transl Res ; 13(10): 11107-11125, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34786046

RESUMEN

The biomarker p16 plays a role in aging and is upregulated in aged organs and cells, including bone marrow mesenchymal stem cells (BM-MSCs), which play a leading role in fracture healing. Several studies have reported delayed fracture healing in geriatric mice. However, the relationship between p16 expression and fracture healing in geriatric mice remains poorly understood. In this study, we found that fracture healing was accelerated in p16 deletion (p16-/-) mice, and the number of migrated BM-MSCs from p16-/- mice increased. The expressions of SDF-1 and CXCR4 were also upregulated in p16-/- mice. Increased cell percentage at S phase in cell cycle, enhanced expressions of CDK4/6, pRB, and E2F1, decreased expression of RB, and elevated expressions of SOX9, PCNA, and COL2A1 were detected in p16-/- mice. The expressions of COL10A1, MMP13, OSTERIX, and COL1A1 were also high in p16-/- mice. Moreover, the expressions of p-AKT, p-mTOR, HIF-1α, and VEGF-A in BM-MSCs and expression of VEGF-A in callus were upregulated in p16-/- mice. The expression of VEGF in the serum of p16-/- mice was also higher than that of wild type mice. Thus, deletion of p16 enhances migration, division, and differentiation of BM-MSCs, promotes proliferation and maturation of chondrocytes, activates osteoblastogenesis, and facilitates vascularization to accelerate fracture healing, providing a novel strategy to treat fracture in the elderly.

14.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 35(7): 862-867, 2021 Jul 15.
Artículo en Chino | MEDLINE | ID: mdl-34308594

RESUMEN

OBJECTIVE: To observe the effect of using tungsten drills to prepare mouse knee osteochondral injury model by comparing with the needle modeling method, in order to provide an appropriate animal modeling method for osteochondral injury research. METHODS: A total of 75 two-month-old male C57BL/6 mice were randomly divided into 3 groups ( n=25). Mice in groups A and B were used to prepare the right knee osteochondral injury models by using needles and tungsten drills, respectively; group C was sham-operation group. The general condition of the mice was observed after operation. The samples were taken at 1 day and 1, 2, 4, and 8 weeks after modeling, and HE staining was performed. The depth, width, and cross-sectional area of the injury site at 1 day in groups A and B were measured, and the percentage of the injury depth to the thickness of the articular cartilage (depth/thickness) was calculated. Toluidine blue staining and immunohistochemical staining for collagen type Ⅱ were performed at 8 weeks, and the International Cartilage Research Society (ICRS) score was used to evaluate the osteochondral healing in groups A and B. RESULTS: All mice survived to the completion of the experiment. HE staining showed that group C had normal cartilage morphology. At 1 day after modeling, the injury in group A only broke through the cartilage layer and reached the subchondral bone without entering the bone marrow cavity; the injury in group B reached the bone marrow cavity. The depth, width, cross-sectional area, and depth/thickness of the injury in group A were significantly lower than those in group B ( P<0.05). At 1, 2, 4, and 8 weeks after modeling, there was no obvious tissue filling in the injured part of group A, and no toluidine blue staining and expression of collagen type Ⅱ were observed at 8 weeks; while the injured part of group B was gradually filled with tissue, the toluidine blue staining and the expression of collagen type Ⅱ were seen at 8 weeks. At 8 weeks, the ICRS score of group A was 8.2±1.3, which was lower than that of group B (13.6±0.9), showing significant difference ( t=-7.637, P=0.000). CONCLUSION: The tungsten drills can break through the subchondral bone layer and enter the bone marrow cavity, and the injury can heal spontaneously. Compared with the needle modeling method, it is a better method for modeling knee osteochondral injury in mice.


Asunto(s)
Cartílago Articular , Traumatismos de la Rodilla , Animales , Modelos Animales de Enfermedad , Articulación de la Rodilla , Masculino , Ratones , Ratones Endogámicos C57BL , Cicatrización de Heridas
15.
Int J Biol Macromol ; 140: 877-885, 2019 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-31446107

RESUMEN

A category of polyethylene glycol-polyurethane (PU) foams were prepared by chitosan (CS) with different molecular weight as chain extender. The activity group, CS grafting degree, crystallization behavior, morphology, thermal stability, mechanical properties, hydrophilicity, protein adsorption and degradation in vitro of PU-CS composite foams were investigated. The experimental results indicated that better group reactivity (-NH2 and -OH) in CS with low molecular weight led to the higher CS grafting degree (78.9% and 98.3%) in the PU foams modified by aminoglucose (CA) and chito-oligosaccharide in 3000 g/mol (CS3K). The disordered crystallization behavior of PU-CA composite foams appeared due to both -NH2 and C6-OH in CA with high activity. However, a clear crystallization diffuse peak in PU-CS3K similar to that in pure PU was presented because the activity of -NH2 in CS3K was relatively high. The phase separation and disorder bubble holes appeared in PU-CS composite foam when CS with high molecular weight in 30,000 g/mol and 300,000 g/mol (CS30K and CS300K) were used. It was the high grafting degree of CS that PU-CS3K had relatively high thermal stability. With the increase of CS molecular weight, the tensile strength, the hydrophobicity, the protein adsorption and the degradation rate of PU-CS composite foam increased. Although pure PU and PU-CS composite foam with low molecular weight of CS (CA and CS3K) have similar hydrophilicity, the adsorption amount of BSA on the latter increases obviously owing to the electrostatic adsorption of amino groups, and the degradation rate of latter during the early stage of degradation is lower than that of former due to the relatively large number of chemical crosslinking sites. These experimental results presented new suggestions for the research and application of CS in PU based biomaterials.


Asunto(s)
Quitosano/química , Polietilenglicoles/química , Poliuretanos/química , Adsorción , Interacciones Hidrofóbicas e Hidrofílicas , Fenómenos Mecánicos , Estructura Molecular , Peso Molecular , Espectroscopía Infrarroja por Transformada de Fourier , Termogravimetría , Difracción de Rayos X
16.
Oncol Rep ; 33(5): 2495-503, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25779224

RESUMEN

Human monopolar spindle-one-binder 2 (hMOB2) is a member of the hMOB family of proteins, and it has been reported to regulate the nuclear-Dbf2-related kinase (NDR) activation. However, the function of hMOB2 expression in tumor cell adhesion and motility has not been addressed. Herein, the lentiviral-mediated overexpression and the knockdown of hMOB2 in HepG2 and SMMC-7721 cells was established. It was demonstrated that overexpression of hMOB2 significantly reduced the cell motility and enhanced the cell-matrix adhesion, while the hMOB2 knockdown decreased not only the cell motility, but also the cell-matrix adhesion. Immunofluorescence results showed that both hMOB2 overexpression and knockdown altered assembly of the focal adhesions and the actin cytoskeleton rearrangement. Furthermore, the focal adhesion kinase (FAK)-Src-paxillin signal pathway activated by hMOB2 was confirmed to be involved in controlling the cell motility and the cell-matrix adhesion. These results demonstrated that the altered cell-matrix adhesion and cell motility induced by hMOB2 expression was caused by the assembly of focal adhesions as well as the actin cytoskeleton rearrangement through the activation of the FAK-Src-paxillin signal pathway, unveiling a novel mechanism of cell motility and cell-matrix adhesion regulation induced by hMOB2 expression.


Asunto(s)
Adhesión Celular/genética , Movimiento Celular/genética , Adhesiones Focales/genética , Invasividad Neoplásica/genética , Proteínas del Tejido Nervioso/genética , Citoesqueleto de Actina/genética , Adhesión Celular/fisiología , Línea Celular , Línea Celular Tumoral , Movimiento Celular/fisiología , Activación Enzimática/genética , Matriz Extracelular/genética , Matriz Extracelular/patología , Quinasa 1 de Adhesión Focal/genética , Adhesiones Focales/patología , Genes src/genética , Células HEK293 , Células Hep G2 , Humanos , Invasividad Neoplásica/patología , Paxillin/genética , Transducción de Señal/genética
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