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2.
Sci Bull (Beijing) ; 2024 Apr 13.
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.

3.
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.

4.
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
5.
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.

6.
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.

7.
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.

8.
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.

9.
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.

10.
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.

11.
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
12.
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
13.
J Mater Chem B ; 11(48): 11519-11531, 2023 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-38047895

RESUMO

Non-invasive cancer therapies, especially those based on reactive oxygen species, including photodynamic therapy (PDT), have gained much interest. As emerging photodynamic nanocarriers, metal-organic frameworks (MOFs) based on porphyrin can release reactive oxygen species (ROS) to destroy cancer cells. However, due to the inefficient production of ROS by photosensitizers and the over-expression of glutathione (GSH) in the tumor microenvironment (TME), their therapeutic effect is not satisfactory. Therefore, herein, we developed a multi-functional nanoparticle, HN@Cu-MOF, to enhance the efficacy of PDT. We combined chemical dynamic therapy (CDT) and nitric oxide (NO) therapy by initiating sensitization to PDT and cell apoptosis in the treatment of tumors. The Cu2+-doped MOF reacted with GSH to form Cu+, exhibiting a strong CDT ability to generate hydroxyl radicals (˙OH). The Cu-MOF was coated with HN, which is hyaluronic acid (HA) modified by a nitric oxide donor. HN can target tumor cells over-expressing the CD44 receptor and consume GSH in the cells to release NO. Both cell experiments and in vivo experiments showed an excellent tumor inhibitory effect upon the treatment. Overall, the HN@Cu-MOF nanoparticle-integrated NO gas therapy and CDT with PDT led to a significant enhancement in GSH consumption and a remarkable elevation in ROS production.


Assuntos
Nanopartículas , Neoplasias , Humanos , Espécies Reativas de Oxigênio , Resultado do Tratamento , Neoplasias/tratamento farmacológico , Glutationa , Microambiente Tumoral
14.
Front Neurosci ; 17: 1247290, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37916179

RESUMO

Introduction: The quantification of electroencephalography (EEG) microstates is an effective method for analyzing synchronous neural firing and assessing the temporal dynamics of the resting state of the human brain. Transcranial photobiomodulation (tPBM) is a safe and effective modality to improve human cognition. However, it is unclear how prefrontal tPBM neuromodulates EEG microstates both temporally and spectrally. Methods: 64-channel EEG was recorded from 45 healthy subjects in both 8-min active and sham tPBM sessions, using a 1064-nm laser applied to the right forehead of the subjects. After EEG data preprocessing, time-domain EEG microstate analysis was performed to obtain four microstate classes for both tPBM and sham sessions throughout the pre-, during-, and post-stimulation periods, followed by extraction of the respective microstate parameters. Moreover, frequency-domain analysis was performed by combining multivariate empirical mode decomposition with the Hilbert-Huang transform. Results: Statistical analyses revealed that tPBM resulted in (1) a significant increase in the occurrence of microstates A and D and a significant decrease in the contribution of microstate C, (2) a substantial increase in the transition probabilities between microstates A and D, and (3) a substantial increase in the alpha power of microstate D. Discussion: These findings confirm the neurophysiological effects of tPBM on EEG microstates of the resting brain, particularly in class D, which represents brain activation across the frontal and parietal regions. This study helps to better understand tPBM-induced dynamic alterations in EEG microstates that may be linked to the tPBM mechanism of action for the enhancement of human cognition.

15.
Dalton Trans ; 52(47): 17792-17796, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-37969004

RESUMO

Hard-Soft Acid-Base (HSAB) principle plays an important guiding role in the design and synthesis of novel clusters and coordination compounds, in which "soft acids prefer to react with soft bases, while hard acids have an affinity for hard bases". Based on HSAB principle, four Ag/Ti heterometallic clusters, including Ag2Ti10, Ag2Ti11 with "Ti-encapsulated Ag" configurations, and two "Ag-encapsulated Ti" structures Ag2Ti2 and Ag2Ti12, were synthesized under solvothermal conditions. In addition, Ag2Ti12 exhibited an efficient and stable catalytic activity for sulfide oxidation. This work provides not only a new structural model for the modulation of the catalytic oxidative desulfurization properties of Ag/Ti heterometallic clusters but also a new insight of the utilization of phosphine-containing ligands to regulate the structure of Ag/Ti heterometallic clusters.

16.
Res Sq ; 2023 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-37886539

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 PFC. Overall, this study revealed that tPBM facilitates significant modulation of the directionality of neurophysiological networks in electrophysiological, metabolic, and hemodynamic activities.

17.
Membranes (Basel) ; 13(10)2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37887983

RESUMO

The concentration dependence of the conductivity of ion exchange membranes (IEMs), as well as other transport properties, has been well explained by the contemporary two-phase model (Zabolotsky et al., 1993) considering a gel phase and an inter-gel phase filled with electroneutral solution. Here, this two-phase model has been adopted and first applied in electrolytes containing mixed counter-ions to investigate the correlation between the membrane ionic conductivity and its microstructure. For three representative commercial cation exchange membranes (CEMs), the total membrane conductivity (κT) when in equilibrium with mixed MgSO4 + Na2SO4 and H2SO4 + Na2SO4 electrolytes could be well predicted with the experimental composition of counter-ions in the gel and inter-gel phase, as well as the counter-ion mobility in the gel phase when the membrane is in a single electrolyte. It is found that the volume fraction of the inter-gel phase (f2) has little impact on the predicted results. The accuracy of the model can be largely improved by calculating the inter-gel phase conductivity (κin) with the ionic mobility being the same as that in the external solution (obtained via simulation in the OLI Studio), rather than simply as equivalent to the conductivity of the external solution (κs). Moreover, a nonlinear correlation between the CEMs' conductivities and the counter-ion composition in the gel phase is observed in the mixed MgSO4 + Na2SO4 solution, as well as for the Nafion117 membrane in the presence of sulfuric acid. For CEMs in mixed MgSO4 + Na2SO4 electrolytes, the calculated conductivity values considering the interaction parameter σ, similar to the Kohlrausch's law, are closer to the experimental ones. Overall, this work provides new insights into membrane conductivity with mixed counter-ions and testifies to the applicability of the contemporary two-phase model.

18.
Artigo em Inglês | MEDLINE | ID: mdl-37861912

RESUMO

Peripheral artery disease (PAD) is a prevalent cardiovascular disease with risks of limb loss. Our objective is to establish an autologous cell source for vascular regeneration to achieve limb salvage in PAD. Six PAD patients (age 50-80) were enrolled with their peripheral blood collected to derive vascular endothelial cells (ECs) with two different approaches: (1) endothelial progenitor cell (EPC) approach and (2) induced pluripotent stem cell (iPSC) approach. The iPSC approach successfully generated patient-specific ECs for all PAD patients, while the EPC approach did not yield any colony-forming ECs in any of the patients. The patient-derived iPSC-ECs expressed endothelial markers and exhibited endothelial functions. However, elevated inflammatory status with VCAM-1 expression was observed in the patient-derived cells. Pharmacological treatment with resveratrol resulted in patient-specific responses in cell viability and VCAM-1 expression. Our study demonstrates the potential of iPSC-ECs for autologous regenerative therapy in PAD, offering promise for personalized treatments for ischemic PAD. Our study establishes autologous endothelial cells from induced pluripotent stem cells as a cellular resource for regenerative treatments in peripheral artery disease.

19.
Angew Chem Int Ed Engl ; 62(47): e202312733, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-37819157

RESUMO

Chiral induction has been an important topic in chemistry, not only for its relevance in understanding the mysterious phenomenon of spontaneous symmetry breaking in nature but also due to its critical implications in medicine and the chiral industry. The induced chirality of fullerenes by host-guest interactions has been rarely reported, mainly attributed to their chiral resistance from high symmetry and challenges in their accessibility. Herein, we report two new pairs of chiral porous aromatic cages (PAC), R-PAC-2, S-PAC-2 (with Br substituents) and R-PAC-3, S-PAC-3 (with CH3 substituents) enantiomers. PAC-2, rather than PAC-3, achieves fullerene encapsulation and selective binding of C70 over C60 in fullerene carbon soot. More significantly, the occurrence of chiral induction between R-PAC-2, S-PAC-2 and fullerenes is confirmed by single-crystal X-ray diffraction and the intense CD signal within the absorption region of fullerenes. DFT calculations reveal the contribution of electrostatic effects originating from face-to-face arene-fullerene interactions dominate C70 selectivity and elucidate the substituent effect on fullerene encapsulation. The disturbance from the differential interactions between fullerene and surrounding chiral cages on the intrinsic highly symmetric electronic structure of fullerene could be the primary reason accounting for the induced chirality of fullerene.

20.
Bioengineering (Basel) ; 10(9)2023 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-37760145

RESUMO

Transcranial photobiomodulation (tPBM) has been suggested as a non-invasive neuromodulation tool. The repetitive administration of light-emitting diode (LED)-based tPBM for several weeks significantly improves human cognition. To understand the electrophysiological effects of LED-tPBM on the human brain, we investigated alterations by repeated tPBM in vigilance performance and brain networks using electroencephalography (EEG) in healthy participants. Active and sham LED-based tPBM were administered to the right forehead of young participants twice a week for four weeks. The participants performed a psychomotor vigilance task (PVT) during each tPBM/sham experiment. A 64-electrode EEG system recorded electrophysiological signals from each participant during the first and last visits in a 4-week study. Topographical maps of the EEG power enhanced by tPBM were statistically compared for the repeated tPBM effect. A new data processing framework combining the group's singular value decomposition (gSVD) with eLORETA was implemented to identify EEG brain networks. The reaction time of the PVT in the tPBM-treated group was significantly improved over four weeks compared to that in the sham group. We observed acute increases in EEG delta and alpha powers during a 10 min LED-tPBM while the participants performed the PVT task. We also found that the theta, beta, and gamma EEG powers significantly increased overall after four weeks of LED-tPBM. Combining gSVD with eLORETA enabled us to identify EEG brain networks and the corresponding network power changes by repeated 4-week tPBM. This study clearly demonstrated that a 4-week prefrontal LED-tPBM can neuromodulate several key EEG networks, implying a possible causal effect between modulated brain networks and improved psychomotor vigilance outcomes.

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