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1.
J Orthop Surg Res ; 19(1): 387, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38956661

RESUMO

Spinal cord injury (SCI) is a severe condition with an extremely high disability rate. It is mainly manifested as the loss of motor, sensory and autonomic nerve functions below the injury site. High-frequency transcranial magnetic stimulation, a recently developed neuromodulation method, can increase motor function in mice with spinal cord injury. This study aimed to explore the possible mechanism by which transcranial magnetic stimulation (TMS) restores motor function after SCI. A complete T8 transection model of the spinal cord was established in mice, and the mice were treated daily with 15 Hz high-frequency transcranial magnetic stimulation. The BMS was used to evaluate the motor function of the mice after SCI. Western blotting and immunofluorescence were used to detect the expression of Connexin43 (CX43) and autophagy-related proteins in vivo and in vitro, and correlation analysis was performed to study the relationships among autophagy, CX43 and motor function recovery after SCI in mice. Western blotting was used to observe the effect of magnetic stimulation on the expression of mTOR pathway members. In the control group, the expression of CX43 was significantly decreased, and the expression of microtubule-associated protein 1 A/1b light chain 3 (LC3II) and P62 was significantly increased after 4 weeks of spinal cord transection. After high-frequency magnetic stimulation, the level of CX43 decreased, and the levels of LC3II and P62 increased in primary astrocytes. The BMS of the magnetic stimulation group was greater than that of the control group. High-frequency magnetic stimulation can inhibit the expression of CX43, which negatively regulates autophagic flux. HF-rTMS increased the expression levels of mTOR, p-mTOR and p-S6. Our experiments showed that rTMS can restore hindlimb motor function in mice after spinal cord injury via regulation of the Cx43-autophagy loop and activation of the mTOR signalling pathway.


Assuntos
Autofagia , Conexina 43 , Recuperação de Função Fisiológica , Traumatismos da Medula Espinal , Estimulação Magnética Transcraniana , Animais , Estimulação Magnética Transcraniana/métodos , Traumatismos da Medula Espinal/metabolismo , Traumatismos da Medula Espinal/fisiopatologia , Traumatismos da Medula Espinal/terapia , Recuperação de Função Fisiológica/fisiologia , Conexina 43/metabolismo , Autofagia/fisiologia , Camundongos , Serina-Treonina Quinases TOR/metabolismo , Camundongos Endogâmicos C57BL , Atividade Motora/fisiologia , Modelos Animais de Doenças , Masculino , Feminino
2.
Chem Commun (Camb) ; 60(54): 6949-6952, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38887804

RESUMO

An electrochemical sensor based on porous aromatic cages was reported, which can achieve chiral sensing of DOPA enantiomers. The prepared sensor can achieve a recognition efficiency of up to 2.6 for DOPA enantiomers. The enhanced recognition efficiency could be attributed to the cooperation of intermolecular interactions, and the efficient charge transfer process.

3.
Acta Biomater ; 182: 81-92, 2024 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-38734287

RESUMO

Tuning cell adhesion geometry can affect cytoskeleton organization and the distribution of cytoskeleton forces, which play critical roles in controlling cell functions. To elucidate the geometrical relationship with cytoskeleton force distribution, it is necessary to control cell morphology. In this study, a series of dextral vortex micropatterns were prepared to precisely control cell morphology for investigating the influence of the curvature degree of adhesion curves on intracellular force distribution and stem cell differentiation at a sub-cellular level. Peripherial actin filaments of micropatterned cells were assembled along the adhesion curves and showed different orientations, filament thicknesses and densities. Focal adhesion and cytoskeleton force distribution were dependent on the curvature degree. Intracellular force distribution was also regulated by adhesion curves. The cytoskeleton and force distribution affected the osteogenic differentiation of mesenchymal stem cells through a YAP/TAZ-mediated mechanotransduction process. Thus, regulation of cell adhesion curvature, especially at cytoskeletal filament level, is critical for cell function manipulation. STATEMENT OF SIGNIFICANCE: In this study, a series of dextral micro-vortexes were prepared and used for the culture of human mesenchymal stem cells (hMSCs) to precisely control adhesive curvatures (0°, 30°, 60°, and 90°). The single MSCs on the micropatterns had the same size and shape but showed distinct focal adhesion (FA) and cytoskeleton orientations. Cellular nanomechanics were observed to be correlated with the curvature degrees, subsequently influencing nuclear morphological features. As a consequence, the localization of the mechanotransduction sensor and activator-YAP/TAZ was affected, influencing osteogenic differentiation. The results revealed the pivotal role of adhesive curvatures in the manipulation of stem cell differentiation via the machanotransduction process, which has rarely been investigated.


Assuntos
Diferenciação Celular , Adesões Focais , Mecanotransdução Celular , Células-Tronco Mesenquimais , Osteogênese , Adesões Focais/metabolismo , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Mecanotransdução Celular/fisiologia , Humanos , Osteogênese/fisiologia , Actinas/metabolismo , Adesão Celular , Forma Celular , Proteínas de Sinalização YAP
4.
Environ Res ; 256: 119244, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38810822

RESUMO

Industrial wastewater is a major environmental concern due to its high copper content, which poses significant toxicity to microbial life. Autoinducer-2 (AI-2) can participate in the inter- and intra-species communication and regulate the physiological functions of different bacterial species by producing AI-2 signal molecules. However, there are few research reports on the luxS gene and lsr operon functions for AI-2 in bacteria with a certain tolerance to copper. This study delves into the potential of quorum sensing mechanisms, particularly the AI-2 system, for enhancing microbial resistance to copper toxicity in Klebsiella michiganensis (KM). We detail the critical roles of the luxS gene in AI-2 synthesis and the lsr operon in AI-2 uptake, demonstrating their collective impact on enhancing copper resistance. Our findings show that mutations in the lsr operon, alongside the knockout of the luxS gene in KM strain (KMΔluxSΔlsr), significantly impair the strain's motility (p < 0.0001) and biofilm formation (p < 0.01), underscoring the operon's role in AI-2 transport. These genetic insights are pivotal for developing bioremediation strategies aimed at mitigating copper pollution in wastewater. By elucidating the mechanisms through which KM modulates copper resistance, this study highlights the broader ecological significance of leveraging microbial quorum sensing pathways for sustainable wastewater management.


Assuntos
Proteínas de Bactérias , Liases de Carbono-Enxofre , Cobre , Klebsiella , Óperon , Percepção de Quorum , Cobre/toxicidade , Percepção de Quorum/efeitos dos fármacos , Liases de Carbono-Enxofre/genética , Liases de Carbono-Enxofre/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Klebsiella/genética , Klebsiella/efeitos dos fármacos , Klebsiella/metabolismo , Homosserina/análogos & derivados , Homosserina/metabolismo , Lactonas/metabolismo
5.
J Am Chem Soc ; 146(26): 17854-17865, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38776361

RESUMO

Pancreatic cancer is a highly fatal disease, and existing treatment methods are ineffective, so it is urgent to develop new effective treatment strategies. The high dependence of pancreatic cancer cells on glucose and glutamine suggests that disrupting this dependency could serve as an alternative strategy for pancreatic cancer therapy. We identified the vital genes glucose transporter 1 (GLUT1) and alanine-serine-cysteine transporter 2 (ASCT2) through bioinformatics analysis, which regulate glucose and glutamine metabolism in pancreatic cancer, respectively. Human serum albumin nanoparticles (HSA NPs) for delivery of GLUT1 and ASCT2 inhibitors, BAY-876/V-9302@HSA NPs, were prepared by a self-assembly process. This nanodrug inhibits glucose and glutamine uptake of pancreatic cancer cells through the released BAY-876 and V-9302, leading to nutrition deprivation and oxidative stress. The inhibition of glutamine leads to the inhibition of the synthesis of the glutathione, which further aggravates oxidative stress. Both of them lead to a significant increase in reactive oxygen species, activating caspase 1 and GSDMD and finally inducing pyroptosis. This study provides a new effective strategy for orthotopic pancreatic cancer treatment by dual starvation-induced pyroptosis. The study for screening metabolic targets using bioinformatics analysis followed by constructing nanodrugs loaded with inhibitors will inspire future targeted metabolic therapy for pancreatic cancer.


Assuntos
Glucose , Glutamina , Neoplasias Pancreáticas , Piroptose , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Humanos , Glutamina/química , Glutamina/metabolismo , Glucose/metabolismo , Piroptose/efeitos dos fármacos , Sistema ASC de Transporte de Aminoácidos/metabolismo , Sistema ASC de Transporte de Aminoácidos/antagonistas & inibidores , Nanopartículas/química , Transportador de Glucose Tipo 1/metabolismo , Transportador de Glucose Tipo 1/antagonistas & inibidores , Linhagem Celular Tumoral , Antineoplásicos/farmacologia , Antineoplásicos/química , Antígenos de Histocompatibilidade Menor/metabolismo , Sistema y+ de Transporte de Aminoácidos
6.
Bioact Mater ; 38: 195-206, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38756202

RESUMO

Fully bioresorbable vascular scaffolds (BVSs) aim to overcome the limitations of metallic drug-eluting stents (DESs). However, polymer-based BVSs, such as Abbott's Absorb, the only US FDA-approved BVS, have had limited use due to increased strut thickness (157 µm for Absorb), exacerbated tissue inflammation, and increased risk of major cardiac events leading to inferior clinical performance when compared to metallic DESs. Herein we report the development of a drug-eluting BVS (DE-BVS) through the innovative use of a photopolymerizable, citrate-based biomaterial and a high-precision additive manufacturing process. BVS with a clinically relevant strut thickness of 62 µm can be produced in a high-throughput manner, i.e. one BVS per minute, and controlled release of the anti-restenosis drug everolimus can be achieved by engineering the structure of polymer coatings to fabricate drug-eluting BVS. We achieved the successful deployment of BVSs and DE-BVSs in swine coronary arteries using a custom-built balloon catheter and BVS delivery system and confirmed BVS safety and efficacy regarding maintenance of vessel patency for 28 days, observing an inflammation profile for BVS and DE-BVS that was comparable to the commercial XIENCE™ DES (Abbott Vascular).

7.
Discov Oncol ; 15(1): 186, 2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38796667

RESUMO

Carcinoembryonic antigen-related cell adhesion molecule 6 (CEACAM6) is an immunoglobulin superfamily protein primarily expressed on epithelial surfaces and myeloid cells. It plays a significant role in cancer progression by inhibiting apoptosis, promoting drug resistance, and facilitating cancer cell invasion and metastasis. Overexpression of CEACAM6 has been observed in various cancers, including lung, breast, colorectal, and hepatocellular cancers, and is associated with poorer overall survival and disease-free survival. Its differential expression on tumor cell surfaces makes it a promising cancer marker. This review aims to provide a comprehensive summary of CEACAM6's role in different cancer types, its involvement in signaling pathways, and recent advancements in CEACAM6-targeted treatments.

8.
Sci Rep ; 14(1): 10242, 2024 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-38702415

RESUMO

Cerebral infra-slow oscillation (ISO) is a source of vasomotion in endogenic (E; 0.005-0.02 Hz), neurogenic (N; 0.02-0.04 Hz), and myogenic (M; 0.04-0.2 Hz) frequency bands. In this study, we quantified changes in prefrontal concentrations of oxygenated hemoglobin (Δ[HbO]) and redox-state cytochrome c oxidase (Δ[CCO]) as hemodynamic and metabolic activity metrics, and electroencephalogram (EEG) powers as electrophysiological activity, using concurrent measurements of 2-channel broadband near-infrared spectroscopy and EEG on the forehead of 22 healthy participants at rest. After preprocessing, the multi-modality signals were analyzed using generalized partial directed coherence to construct unilateral neurophysiological networks among the three neurophysiological metrics (with simplified symbols of HbO, CCO, and EEG) in each E/N/M frequency band. The links in these networks represent neurovascular, neurometabolic, and metabolicvascular coupling (NVC, NMC, and MVC). The results illustrate that the demand for oxygen by neuronal activity and metabolism (EEG and CCO) drives the hemodynamic supply (HbO) in all E/N/M bands in the resting prefrontal cortex. Furthermore, to investigate the effect of transcranial photobiomodulation (tPBM), we performed a sham-controlled study by delivering an 800-nm laser beam to the left and right prefrontal cortex of the same participants. After performing the same data processing and statistical analysis, we obtained novel and important findings: tPBM delivered on either side of the prefrontal cortex triggered the alteration or reversal of directed network couplings among the three neurophysiological entities (i.e., HbO, CCO, and EEG frequency-specific powers) in the physiological network in the E and N bands, demonstrating that during the post-tPBM period, both metabolism and hemodynamic supply drive electrophysiological activity in directed network coupling of the prefrontal cortex (PFC). Overall, this study revealed that tPBM facilitates significant modulation of the directionality of neurophysiological networks in electrophysiological, metabolic, and hemodynamic activities.


Assuntos
Eletroencefalografia , Córtex Pré-Frontal , Espectroscopia de Luz Próxima ao Infravermelho , Humanos , Córtex Pré-Frontal/fisiologia , Córtex Pré-Frontal/metabolismo , Masculino , Adulto , Feminino , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Terapia com Luz de Baixa Intensidade/métodos , Adulto Jovem , Descanso/fisiologia , Oxiemoglobinas/metabolismo , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Hemodinâmica/fisiologia , Rede Nervosa/fisiologia , Rede Nervosa/metabolismo
9.
Sci Bull (Beijing) ; 69(12): 1887-1894, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38658235

RESUMO

The efficiency of rigid perovskite/silicon tandem solar cells has reached 33.9%. However, there has been no report on flexible perovskite/silicon tandem solar cells due to the challenge of overcoming the poor light absorption of ultrathin silicon bottom cells while maintaining their mechanical flexibility. Herein, we report the first demonstration of the perovskite/silicon tandem solar cell based on flexible ultrathin silicon. We show that reducing the wafer thicknesses and feature sizes of the light-trapping textures can significantly improve the flexibility of silicon without sacrificing light utilization. In addition, the capping of the perovskite top cells can further improve the device's mechanical durability by shifting the neutral plane toward the silicon surface that is prone to fracture. Finally, the resulting ultrathin (∼30 µm) flexible perovskite/silicon tandem solar cell achieves a certified stabilized efficiency of 22.8% with an extremely high power-to-weight ratio of 3.12 W g-1. Moreover, the flexible tandems exhibit remarkable bending durability, maintaining 98.2% of their initial performance after 3000 bending cycles at a radius of only 1 cm.

10.
RSC Adv ; 14(17): 12096-12106, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38628486

RESUMO

Prussian blue analogues possess numerous advantages as cathode materials for sodium-ion batteries, including high energy density, low cost, sustainability, and straightforward synthesis processes, making them highly promising for practical applications. However, during the synthesis, crystal defects such as vacancies and the incorporation of crystal water can lead to issues such as diminished capacity and suboptimal cycling stability. In the current study, a Y-tube assisted coprecipitation method was used to synthesize iron-based Prussian blue analogues, and the optimized feed flow rate during synthesis contributed to the successful preparation of the material with a formula of Na1.56Fe[Fe(CN)6]0.90□0.10·2.42H2O, representing a low-defect cathode material. This approach cleverly utilizes the Y-tube component to enhance the micro-mixing of materials in the co-precipitation reaction, featuring simplicity, low cost, user-friendly, and the ability to be used in continuous production. Electrochemical performance tests show that the sample retains 69.8% of its capacity after 200 cycles at a current density of 0.5C (1C = 140 mA g-1) and delivers a capacity of 71.9 mA h g-1 at a high rate of 10C. The findings of this research provide important insights for the development of high-performance Prussian blue analogues cathode materials for sodium-ion batteries.

12.
J Mater Chem B ; 12(13): 3249-3261, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38466580

RESUMO

Over the past few decades, the critical role played by cellular contractility associated mechanotransduction in the regulation of cell functions has been revealed. In this case, numerous biomaterials have been chemically or structurally designed to manipulate cell behaviors through the regulation of cellular contractility. In particular, adhesive proteins including fibronectin, poly-L-lysine and collagen type I have been widely applied in various biomaterials to improve cell adhesion. Therefore, clarifying the effects of adhesive proteins on cellular contractility has been valuable for the development of biomaterial design. In this study, reference-free traction force microscopy with a well-organized microdot array was designed and prepared to investigate the relationship between adhesive proteins, cellular contractility, and mechanotransduction. The results showed that fibronectin and collagen type I were able to promote the assembly of focal adhesions and further enhance cellular contraction and YAP activity. In contrast, although poly-L-lysine supported cell spreading and elongation, it was inefficient at inducing cell contractility and activating YAP. Additionally, compared with cellular morphogenesis, cellular contraction was essential for YAP activation.


Assuntos
Fibronectinas , Mecanotransdução Celular , Fibronectinas/metabolismo , Mecanotransdução Celular/fisiologia , Microscopia de Força Atômica , Colágeno Tipo I , Polilisina , Tração , Adesão Celular , Materiais Biocompatíveis
13.
China CDC Wkly ; 6(7): 118-125, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38405601

RESUMO

On July 23, 2022, the World Health Organization (WHO) declared the monkeypox (mpox) outbreak a "Public Health Emergency of International Concern." Since 2022, outbreaks of mpox in many countries around the world have primarily resulted in fatalities among immunocompromised individuals, such as untreated HIV/AIDS patients. Since the eradication of smallpox was declared by the WHO in 1980, the global vaccination against smallpox has been gradually discontinued. China also stopped routine smallpox vaccination in 1981. The protective effect of the smallpox vaccine has decreased over time due to aging and declining immunity in those who were vaccinated. For individuals, timely vaccination against smallpox is an effective means of protection against mpox. However, due to safety concerns with the smallpox vaccine and the limitations of current mpox vaccines, there is no vaccine that is safe, effective, and has low side effects applied in clinical settings. This article provides a comprehensive review of the development of mpox virus (MPXV) vaccines, their application in special populations, and the current state of vaccine research, considering the etiology, transmission, and prevention of the MPXV. Vaccination, as an effective method of epidemic prevention, can provide long-term immune protection and effectively reduce the severity of infection. However, as there is no licensed specific MPXV vaccine available globally, the vaccines currently used for mpox prevention are mostly smallpox vaccines. These smallpox vaccines can offer some degree of protection against mpox by activating cross-protection in the body.

14.
Angew Chem Int Ed Engl ; 63(12): e202319815, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38299255

RESUMO

Piezochromic materials that exhibit pressure-dependent luminescence variations are attracting interest with wide potential applications in mechanical sensors, anticounterfeiting and storage devices. Crystalline porous materials (CPMs) have been widely studied in piezochromism for highly tunable luminescence. Nevertheless, reversible and high-contrast emission response with a wide pressure range is still challenging. Herein, the first example of hierarchical porous cage-based πOF (Cage-πOF-1) with spring structure was synthesized by using aromatic chiral cages as building blocks. Its elastic properties evaluated based on the bulk modulus (9.5 GPa) is softer than most reported CPMs and the collapse point (20.0 GPa) significantly exceeds ever reported CPMs. As smart materials, Cage-πOF-1 displays linear pressure-dependent emission and achieves a high-contrast emission difference up to 154 nm. Pressure-responsive limit is up to 16 GPa, outperforming the CPMs reported so far. Dedicated experiments and density functional theory (DFT) calculations illustrate that π-π interactions-dominated controllable structural shrinkage and porous-spring-structure-mediated elasticity is responsible for the outstanding piezofluorochromism.

15.
bioRxiv ; 2024 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-38405945

RESUMO

Chronic bladder dysfunction due to bladder disease or trauma is detrimental to affected patients as it can lead to increased risk of upper urinary tract dysfunction. Current treatment options include surgical intervention that enlarge the bladder with autologous bowel tissue to alleviate pressure on the upper urinary tract. This highly invasive procedure, termed bladder augmentation enterocystoplasty (BAE), significantly increases risk of patient morbidity and mortality due to the incompatibility between the bowel and bladder tissue. Therefore, patients would significantly benefit from an alternative treatment strategy that can regenerate healthy tissue and restore overall bladder function. Previous research has demonstrated the potential of citrate-based scaffolds co-seeded with bone marrow-derived stem/progenitor cells as an alternative graft for bladder augmentation. Recognizing that contact guidance is known to influence tissue regeneration, we hypothesized that patterned scaffolds would modulate cell responses and improve overall quality of the regenerated bladder tissue. We fabricated microgrooved (MG) scaffolds using citrate-based biomaterial poly(1,8-octamethylene-citrate-co-octanol) (POCO) and co-seeded them with human bone marrow derived mesenchymal stem cells (MSCs) and CD34+ hematopoietic stem/progenitor cells (HSPCs). Microgrooved POCO scaffolds supported MSC and HSPC attachment, and MSC alignment within the microgrooves. All scaffolds were characterized and assessed for bladder tissue regeneration in an established nude rat bladder augmentation model. In all cases, normal physiological function was maintained post-augmentation, even without the presence of stem/progenitor cells. Urodynamic testing at 4-weeks post-augmentation for all experimental groups demonstrated that capacity increased and compliance was normal. Histological evaluation of the regenerated tissue revealed that cell-seeded scaffolds restored normal bladder smooth muscle content and resulted in increased revascularization and peripheral nerve regeneration. The presence of microgrooves on the cell-seeded scaffolds increased microvasculature formation by 20% and urothelium layer thickness by 25% in the regenerating tissue. Thus, this work demonstrates that micropatterning affects bladder regeneration to improve overall anatomical structure and re-establish bladder physiology.

16.
PNAS Nexus ; 3(2): pgae038, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38344009

RESUMO

To date, there are no efficacious translational solutions for end-stage urinary bladder dysfunction. Current surgical strategies, including urinary diversion and bladder augmentation enterocystoplasty (BAE), utilize autologous intestinal segments (e.g. ileum) to increase bladder capacity to protect renal function. Considered the standard of care, BAE is fraught with numerous short- and long-term clinical complications. Previous clinical trials employing tissue engineering approaches for bladder tissue regeneration have also been unable to translate bench-top findings into clinical practice. Major obstacles still persist that need to be overcome in order to advance tissue-engineered products into the clinical arena. These include scaffold/bladder incongruencies, the acquisition and utility of appropriate cells for anatomic and physiologic tissue recapitulation, and the choice of an appropriate animal model for testing. In this study, we demonstrate that the elastomeric, bladder biomechanocompatible poly(1,8-octamethylene-citrate-co-octanol) (PRS; synthetic) scaffold coseeded with autologous bone marrow-derived mesenchymal stem cells and CD34+ hematopoietic stem/progenitor cells support robust long-term, functional bladder tissue regeneration within the context of a clinically relevant baboon bladder augmentation model simulating bladder trauma. Partially cystectomized baboons were independently augmented with either autologous ileum or stem-cell-seeded small-intestinal submucosa (SIS; a commercially available biological scaffold) or PRS grafts. Stem-cell synergism promoted functional trilayer bladder tissue regeneration, including whole-graft neurovascularization, in both cell-seeded grafts. However, PRS-augmented animals demonstrated fewer clinical complications and more advantageous tissue characterization metrics compared to ileum and SIS-augmented animals. Two-year study data demonstrate that PRS/stem-cell-seeded grafts drive bladder tissue regeneration and are a suitable alternative to BAE.

17.
J Colloid Interface Sci ; 662: 807-813, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38382365

RESUMO

Sunlight-driven CO2 reduction to value-added chemicals is an effective strategy to promote carbon recycling. The exploration of catalysts with efficient charge separation is crucially important for highly efficient CO2 photoreduction. In this work, the preparation of metal-cluster-based covalent organic framework (CuABD) integrated features from both metal organic frameworks (MOFs) and covalent organic frameworks (COFs) through the condensation of diamines and functionalized trinuclear copper clusters demonstrate a thoughtful design strategy. The reported yield of 1.3 mmol g-1 h-1 for formic acid (HCOOH) under simulated solar irradiation is impressive, surpassing the performance of many COF- and MOF-based catalysts previously reported. Compared to its isomorphic metal-free structure (named BDFTD) and bare trinuclear Cu cluster which present extremely poor catalytic activities, CuABD displays remarkably enhanced CO2 reduction activity. Experimental and theoretical investigations reveal that the efficient charge transfer between diamine monomer and cyclic trinuclear copper (I) units, and the electron delocalization of the π-conjugated framework are responsible for the appealing catalytic performance. In summary, the work presents a well-structured and scientifically sound exploration of a metal-cluster-based covalent organic framework for efficient CO2 reduction under sunlight.

18.
J Colloid Interface Sci ; 659: 385-396, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38181702

RESUMO

HYPOTHESIS: Chronic wounds, particularly those caused by diabetes, pose a significant challenge for clinical treatment due to their prolonged healing process and associated complications, which can lead to increased morbidity. A biocompatible hydrogel with strong antibacterial properties and the ability to promote angiogenesis can be directly absorbed in the wound site for healing. EXPERIMENTS: A series of self-healing, antibacterial bolaamphiphilic supramolecular self-assembling hydrogels (HLQMes/Cu) were developed based on metal-ligand coordination between various concentrations of Cu2+ solution and the head group of l-histidine methyl ester in HLQMes. This is the first report on the application of bola-molecular supramolecular hydrogels for the treatment of chronic wounds. FINDINGS: The bola-molecular hydrogels reduced the toxicity of copper ions by coordination, and the HLQMes/Cu hydrogel, with 1.3 mg/mL Cu2+ (HLQMes/Cu1.3), demonstrated good biocompatibility and antibacterial properties and effectively enhanced wound healing in a diabetic wound model with full-thickness injuries. Immunohistochemical analysis revealed that the HLQMes/Cu1.3 hydrogel enhanced epithelial formation and collagen deposition in wounds. Immunofluorescence studies confirmed that the HLQMes/Cu1.3 hydrogel attenuated the expression of proinflammatory factor (IL-6) and promoted angiogenesis by upregulating α-SMA and CD31. These findings demonstrate the potential of this bolaamphiphilic supramolecular self-assembling hydrogel as a promising candidate for diabetic wound treatment.


Assuntos
Diabetes Mellitus , Hidrogéis , Humanos , Hidrogéis/farmacologia , Hidrogéis/química , Cobre/farmacologia , Cicatrização , Antibacterianos/química
19.
Dalton Trans ; 53(6): 2541-2550, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38234224

RESUMO

Halide perovskite nanocrystals are innovative luminescent materials for fluorescent probes with high quantum yield and narrow emission bandwidth. However, the limited stability, single-signal response, and separation challenges obstruct their widespread use in water ion detection. Herein, a ratiometric fluorescence sensor based on terbium alginate gel beads (green fluorescent, namely Tb-AG) embedded with powdered CsPbI3@Pb-MOF (red fluorescent) was prepared for fluorescent determination and adsorption of Fe3+. Pb-MOF's protection notably enhances the water stability of CsPbI3, while the energy transfer between CsPbI3@Pb-MOF and Tb3+ elevates the optical performance of CsPbI3@Pb-MOF@Tb-AG. Significantly, Fe3+ markedly suppresses CsPbI3@Pb-MOF red fluorescence at 647 nm, while not noticeably affecting Tb-AG green emission at 528 nm. The sensor exhibited a strong linear response to Fe3+ concentrations ranging from 0 to 90 µM, with a detection limit of 0.44 µM and high selectivity. The CsPbI3@Pb-MOF@Tb-AG-based sensor has been effectively validated through its successful use in detecting Fe3+ in tap and river water samples. Furthermore, CsPbI3@Pb-MOF@Tb-AG demonstrates a notable adsorption capacity of 325.4 mg g-1 Fe3+. Finally, the mechanism of Fe3+ detection and adsorption was determined.

20.
Recent Pat Anticancer Drug Discov ; 19(3): 373-382, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37464821

RESUMO

OBJECTIVE: We aimed to identify critical clinical features to develop an accurate webbased prediction model for estimating the overall survival (OS) of primary breast diffuse large Bcell lymphoma (PB-DLBCL) adult patients. METHODS: We first included all PB-DLBCL cases with available covariates retrieved from the Surveillance, Epidemiology, and End Results database. We sequentially performed univariate and multivariate Cox regression approaches to identify the predictors independently associated with prognosis, and all the predictors that passed these tests were then constructed to build a nomogram for predicting 3-, 5-, and 10-year survival rates of patients. The C-index and the receiver operating characteristic curve (ROC) were used to evaluate the prediction discrimination, and the calibration curve was applied to estimate the calibration. RESULTS: A total of PB-DLBCL adult patients were included (median age was 69 with the interquartile range [IQR] of 57-79 years), of which 466 (70%) were randomly allocated to the development cohort, and the remaining cases were collected for validation. Using three identified independent predictors (i.e., age, stage, and radiation), an accurate nomogram for predicting OS was developed and validated. The C-indices of our nomogram were both relatively acceptable, with 0.74 (95% CI: 0.71-0.78) and 0.72 (95% CI: 0.70-0.75) for the development and validation cohorts, respectively. The calibration curves also accurately predicted the prognosis of PB-DLBCL in all cases. In addition, ROC curves showed our nomogram to possess superior predictive ability compared to any single variable. To visually present this prediction model, a convenient webbased tool was implemented based on our prognostic nomogram. CONCLUSION: For patients with PB-DLBCL, a more convenient and accurate web-based prediction model was developed and validated, which showed relatively good performances in both discrimination and calibration during model development and validation. External evaluation and validation are warranted by further independent studies.


Assuntos
Linfoma Difuso de Grandes Células B , Idoso , Humanos , Pessoa de Meia-Idade , Bases de Dados Factuais , Linfoma Difuso de Grandes Células B/diagnóstico , Linfoma Difuso de Grandes Células B/epidemiologia , Nomogramas , Prognóstico
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