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1.
Nat Mater ; 23(6): 775-781, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38182811

RESUMEN

The discovery of superconductivity in infinite-layer nickelates established another category of unconventional superconductors that shares structural and electronic similarities with cuprates. However, key issues of the superconducting pairing symmetry, gap amplitude and superconducting fluctuations are yet to be addressed. Here we utilize static and ultrafast terahertz spectroscopy to address these. We demonstrate that the equilibrium terahertz conductivity and non-equilibrium terahertz responses of an optimally Sr-doped nickelate film (superconducting transition temperature of Tc = 17 K) are in line with the electrodynamics of d-wave superconductivity in the dirty limit. The gap-to-Tc ratio (2Δ/kBTc) is found to be 3.4, indicating that the superconductivity falls in the weak coupling regime. In addition, we observed substantial superconducting fluctuations near Tc that do not extend into the deep normal state as the optimally hole-doped cuprates do. Our results support a d-wave system that closely resembles the electron-doped cuprates.

2.
EMBO J ; 39(13): e103325, 2020 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-32510170

RESUMEN

Communication between myeloid cells and epithelium plays critical role in maintaining intestinal epithelial barrier integrity. Myeloid cells interact with intestinal epithelial cells (IECs) by producing various mediators; however, the molecules mediating their crosstalk remain incompletely understood. Here, we report that deficiency of angiogenin (Ang) in mouse myeloid cells caused impairment of epithelial barrier integrity, leading to high susceptibility to DSS-induced colitis. Mechanistically, myeloid cell-derived angiogenin promoted IEC survival and proliferation through plexin-B2-mediated production of tRNA-derived stress-induced small RNA (tiRNA) and transcription of ribosomal RNA (rRNA), respectively. Moreover, treatment with recombinant angiogenin significantly attenuated the severity of experimental colitis. In human samples, the expression of angiogenin was significantly down-regulated in patients with inflammatory bowel disease (IBD). Collectively, we identified, for the first time to our knowledge, a novel mediator of myeloid cell-IEC crosstalk in maintaining epithelial barrier integrity, suggesting that angiogenin may serve as a new preventive agent and therapeutic target for IBD.


Asunto(s)
Mucosa Intestinal/metabolismo , Células Mieloides/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Ribonucleasa Pancreática/metabolismo , Transducción de Señal , Animales , Comunicación Celular/genética , Colitis/inducido químicamente , Colitis/genética , Colitis/metabolismo , Sulfato de Dextran/toxicidad , Humanos , Mucosa Intestinal/patología , Ratones , Ratones Noqueados , Células Mieloides/patología , Proteínas del Tejido Nervioso/genética , ARN Ribosómico/genética , ARN Ribosómico/metabolismo , Ribonucleasa Pancreática/genética
3.
Small ; : e2402993, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38750614

RESUMEN

2D covalent organic framework (COF) materials with extended conjugated structure and periodic columnar π-arrays exhibit promising applications in organic optoelectronics. However, there is a scarcity of reports on optoelectronic COFs, mainly due to the lack of suitable π-skeletons. Here, two multi-functional optoelectronic 2D COFs DPP-TPP-COF and DPP-TBB-COF are constructed with diketopyrrolopyrrole as electron acceptor (A), and 1,3,6,8-tetraphenylpyrene and 1,3,5-triphenylbenzene as electron donor (D) through imine bonds. Both 2D COFs showed good crystallinities and AA stacking with a rhombic framework for DPP-TPP-COF and hexagonal one for DPP-TBB-COF, respectively. The electron D-A and ordered intermolecular packing structures endow the COFs with broad UV-vis absorptions and narrow bandgaps along with suitable HOMO/LUMO energy levels, resulting in multi-functional optoelectronic properties, including photothermal conversion, supercapacitor property, and ambipolar semiconducting behavior. Among them, DPP-TPP-COF exhibits a high photothermal conversion efficiency of 47% under 660 nm laser irradiation, while DPP-TBB-COF exhibits superior specific capacitance of 384 F g-1. Moreover, P-type doping and N-type doping are achieved by iodine and tetrakis(dimethylamino)ethylene on a single host COF, resulting in ambipolar semiconducting behavior. These results provide a paradigm for the application of multi-functional optoelectronic COF materials.

4.
Langmuir ; 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-39014533

RESUMEN

By combining molecular simulations and experimental measurements, the effect of the Nafion content on the performance of proton-exchange membrane fuel cells (PEMFCs) is explained from the perspective of the triple-phase boundary (TPB). The evaporation process of Nafion solvent is simulated on a triple-phase model to mimic the formation of the TPB, and the influence of the Nafion content on the TPB structure is investigated. When the Nafion content is 1.415 mg/m2, the coverages of Nafion on both Pt particles and the carbon carrier are saturated at 42.1% and 32.7%, respectively. With the increase of Nafion content, the amount of water molecules around Pt particles is increased, and the surrounding O2 content is decreased. The experimental PEMFC performance has confirmed such simulation results, which demonstrates a trend of enhancing first and then weakening with the increase of Nafion content and reaches a maximum with the Nafion content of 2.96 mg/m2. Therefore, the correlation between the structure of the TPB and the cell's efficiency has been established at a molecular level, enabling enhancements in the design of the TPB morphology and an increase in PEMFC efficiency.

5.
Environ Sci Technol ; 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38985512

RESUMEN

While flow-electrode capacitive deionization (FCDI) is recognized as an attractive desalination technology, its practical implementation has been hindered by the ease of scaling and energy-intensive nature of the single-cell FCDI system, particularly when treating brackish water with elevated levels of naturally coexisting SO42- and Ca2+. To overcome these obstacles, we propose and design an innovative ion-selective metathesis FCDI (ISM-FCDI) system, consisting of a two-stage tailored cell design. Results indicate that the specific energy consumption per unit volume of water for the ISM-FCDI is lower (by up to ∼50%) than that of a conventional single-stage FCDI due to the parallel circuit structure of the ISM-FCDI. Additionally, the ISM-FCDI benefits from a conspicuous disparity in the selective removal of ions at each stage. The separate storage of Ca2+ and SO42- by the metathesis process in the ISM-FCDI (46.25% Ca2+, 14.25% SO42- in electrode 1 and 4.75% Ca2+, 35.25% SO42- in electrode 2) can effectively prevent scaling. Furthermore, configuration-performance analysis on the ion-selective migration suggests that the properties of the ion exchange membrane, rather than the carbon species, govern the selectivity of ion removal. This work introduces system-level enhancements aimed at enhancing energy conservation and scaling prevention, providing critical optimization of the FCDI for brackish water softening.

6.
Dig Dis Sci ; 69(4): 1253-1262, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38361148

RESUMEN

BACKGROUND: Intrahepatic cholestasis of pregnancy (ICP) is associated with adverse pregnancy outcomes; however, the underlying mechanisms are not fully understood. AIMS: This study aimed to determine the role of exosomal miR-6891-5p in placental trophoblast dysfunction in ICP and identify new biomarkers for ICP diagnosis. METHODS: Serum samples were collected from ICP patients and healthy pregnant women, and serum exosomes were extracted and identified. Fluorescent dye labeling of exosomes and cell-verified cell phagocytosis were performed. In vitro experiments were conducted by adding taurocholic acid to simulate the ICP environment. Cell proliferation and apoptosis levels were detected using flow cytometry and the cell counting kit-8 assay. Mimics were constructed to overexpress miR-6891-5p in cells, and the binding site between miR-6891-5p and YWHAE was verified using luciferase reporter genes. RESULTS: miR-6891-5p expression was significantly decreased in serum exosomes of ICP patients. Co-culturing with exosomes derived from ICP patients' serum (ICP-Exos) decreased HTR-8/SVeno cell proliferation and increased apoptosis levels. miR-6891-5p upregulation in HTR-8/SVeno cells significantly increased cell viability and reduced cell apoptosis levels, as determined by the cell counting kit-8 assay and flow cytometry. A double luciferase assay confirmed that miR-6891-5p affected the expression of the downstream YWHAE protein. CONCLUSIONS: This study indicates that serum exosomes from ICP patients can impact the apoptosis of placental trophoblast HTR-8/SVeno cells through the miR-6891-5P/YWHAE pathway and can serve as specific molecular markers for ICP diagnosis.


Asunto(s)
Colestasis Intrahepática , Exosomas , MicroARNs , Complicaciones del Embarazo , Femenino , Humanos , Embarazo , Proteínas 14-3-3/metabolismo , Apoptosis , Proliferación Celular , Colestasis Intrahepática/genética , Colestasis Intrahepática/metabolismo , Exosomas/genética , Luciferasas/metabolismo , MicroARNs/sangre , MicroARNs/genética , MicroARNs/metabolismo , Placenta/metabolismo , Complicaciones del Embarazo/genética , Complicaciones del Embarazo/metabolismo
7.
Brain Inj ; 38(7): 524-530, 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38433503

RESUMEN

BACKGROUND: Autophagy is recognized as a promising therapeutic target for traumatic brain injury (TBI). Crocetin is an aglycone of crocin naturally occurring in saffron and has been found to alleviate brain injury diseases. However, whether crocetin affects autophagy after TBI remains unknown. Therefore, we explore crocetin roles in autophagy after TBI. METHODS: We used a weight-dropped model to induce TBI in C57BL/6J mice. Neurological severity scoring (NSS) and grip tests were used to evaluate the neurological level of injury. Brain edema, neuronal apoptosis, neuroinflammation and autophagy were detected by measurements of brain water content, TUNEL staining, ELISA kits and western blotting. RESULTS: Crocetin ameliorated neurological dysfunctions and brain edema after TBI. Crocetin reduced neuronal apoptosis and neuroinflammation and enhanced autophagy after TBI. CONCLUSION: Crocetin alleviates TBI by inhibiting neuronal apoptosis and neuroinflammation and activating autophagy.


Asunto(s)
Apoptosis , Autofagia , Lesiones Traumáticas del Encéfalo , Carotenoides , Modelos Animales de Enfermedad , Ratones Endogámicos C57BL , Fármacos Neuroprotectores , Vitamina A , Animales , Carotenoides/farmacología , Carotenoides/uso terapéutico , Vitamina A/análogos & derivados , Lesiones Traumáticas del Encéfalo/tratamiento farmacológico , Lesiones Traumáticas del Encéfalo/patología , Autofagia/efectos de los fármacos , Apoptosis/efectos de los fármacos , Ratones , Masculino , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/uso terapéutico , Edema Encefálico/tratamiento farmacológico , Encéfalo/efectos de los fármacos , Encéfalo/patología , Neuronas/efectos de los fármacos , Neuronas/patología
8.
Ecotoxicol Environ Saf ; 273: 116127, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38394756

RESUMEN

Alkaline stress poses a significant challenge to the healthy growth of fish. Ginger polysaccharide (GP) is one of the main active substances in ginger and has pharmacological effects, such as anti-oxidation and immune regulation. However, the physiological regulatory mechanism of GP addition to diet on alkalinity stress in crucian carp remains unclear. This study aimed to investigate the potential protective effects of dietary GP on antioxidant capacity, gene expression levels, intestinal microbiome, and metabolomics of crucian carp exposed to carbonate (NaHCO3). The CK group (no GP supplementation) and COG group (NaHCO3 stress and no GP supplementation) were set up. The GPCS group (NaHCO3 stress and 0.4% GP supplementation) was stressed for seven days. Based on these data, GP significantly increased the activities of total antioxidant capacity (T-AOC), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-PX), acid phosphatase (ACP), and alkaline phosphatase (AKP) in carp under alkalinity stress (p < 0.05) and decreased the activity of malon dialdehyde (MDA) (p < 0.05). GP restored the activity of GSH-PX, ACP, and AKP to CK levels. The expression levels of tumor necrosis factor ß (TGF-ß), tumor necrosis factor-alpha (TNF-α), interferon-gamma (IFN-γ), and interleukin 8 (IL-8) genes were decreased, and the expression levels of determination factor kappa-B (NF-κB) and interleukin 10 (IL-10) genes were increased (p < 0.05). Based on 16 S rRNA high-throughput sequencing, GP improved the changes in the intestinal microbial diversity and structural composition of crucian carp caused by NaHCO3 exposure. In particular, GP increased the relative abundance of Proteobacteria and Bacteroidetes and decreased the relative abundance of Actinobacteria. The metabolic response of GP to NaHCO3 exposed crucian carp guts was studied using LC/MS. Compared to the COG group, the GPCS group had 64 different metabolites and enriched 10 metabolic pathways, including lipid metabolism, nucleotide metabolism, and carbohydrate metabolism. The addition of GP to feed can promote galactose metabolism and provide an energy supply to crucian carp, thus alleviating the damage induced by alkalinity stress. In conclusion, GP can mitigate the effects of NaHCO3 alkalinity stress by regulating immune function, intestinal flora, and intestinal metabolism in crucian carp. These findings provide a novel idea for studying the mechanism of salt-alkali tolerance in crucian carp by adding GP to feed.


Asunto(s)
Carpas , Microbioma Gastrointestinal , Zingiber officinale , Animales , Carpa Dorada/metabolismo , Carpas/metabolismo , Antioxidantes/metabolismo , Dieta , Carbonatos , Alimentación Animal/análisis
9.
Sensors (Basel) ; 24(2)2024 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-38257499

RESUMEN

To meet the complex and diverse demands for low-stress mechanical measurements of fabrics and other flexible materials, two integrated multidimensional force sensors with the same structure but different ranges were explored. They can support both rapid and precise low-noise, high-precision, low-cost, easy-to-use, reliable, and intelligent solutions for the complex measurement of fabric mechanics. Having analysed the mechanical relationship of the parallel beam theory, and considering the specific requirements of fabric measurement, a novel multi-dimensional force sensor is designed, capable of measuring tensile, shear, and buckling properties. Finite element analysis is used to simulate the mechanical performance of this sensor for fabric-loading/unloading measurement, and the sensitivity of the mechanical quantity transfer, the amount of sensor deformation, the stress distribution, and the degree of inter-dimensional coupling have been investigated and verified. The basis for subsequent digital processing is achieved by a low-offset, low-temperature-drift, low-power-consumption analogue front end, 24-bit ADC circuit, and signal conditioning electronics, suitable for the measurement of fabric mechanics under low stress, which is like the end-user requirements. The sensor information channel is supported by a host microcontroller with a DSP and a floating-point processing instruction set. Information processing is performed in time-sharing with the support of a multitasking real-time operating system. The purpose of designing this sensor is to facilitate the development of a new testing instrument, which will adopt the advances of current instruments whilst eliminating their shortcomings.

10.
Sensors (Basel) ; 24(11)2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38894084

RESUMEN

Scanning ion conductance microscopy (SICM) enables the non-invasive three-dimensional imaging of live cells and other structures in physiological environments. However, when imaging complex samples, SICM faces challenges such as having a low temporal resolution during slow scanning and a reduced signal-to-noise ratio during fast scanning, making it difficult to simultaneously improve both temporal and spatial resolution. To address these issues, this paper proposes an algorithm for enhancing image resolution under high-speed scanning. Firstly, scanning images are preprocessed using a median filtering algorithm to remove the salt-and-pepper noise generated during high-speed scanning. Next, the Canny edge detection algorithm is employed to extract the edges of the image targets. To avoid blurring the edges, the new edge-directed interpolation (NEDI) algorithm is then used to fill the edges, while non-edge areas are filled using bilinear interpolation, thereby enhancing the image resolution. Finally, the peak signal-to-noise ratio (PSNR) and structural similarity index (SSIM) are used to analyze the imaging of articular chondrocytes. The results show that under a scanning speed of 480 nm/ms, the proposed algorithm improves the temporal resolution of imaging by 60% compared to traditional 2× resolution imaging, increases the peak signal-to-noise ratio of the scanning images by 7 dB, and achieves a structural similarity of 0.97. Therefore, the proposed algorithm effectively removes noise during high-speed scanning and improves the SICM scanning imaging resolution, thereby avoiding the reduction in temporal resolution when scanning larger resolution samples and effectively enhancing the performance of SICM scanning imaging.

11.
Compr Rev Food Sci Food Saf ; 23(1): e13264, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-38284582

RESUMEN

Staphylococcal enterotoxins (SEs), the major virulence factors of Staphylococcus aureus, cause a wide range of food poisoning and seriously threaten human health by infiltrating the food supply chain at different phases of manufacture, processes, distribution, and market. The significant prevalence of Staphylococcus aureus calls for efficient, fast, and sensitive methods for the early detection of SEs. Here, we provide a comprehensive review of the hazards of SEs in contaminated food, the characteristic and worldwide regulations of SEs, and various detection methods for SEs with extensive comparison and discussion of benefits and drawbacks, mainly including biological detection, genetic detection, and mass spectrometry detection and biosensors. We highlight the biosensors for the screening purpose of SEs, which are classified according to different recognition elements such as antibodies, aptamers, molecularly imprinted polymers, T-cell receptors, and transducers such as optical, electrochemical, and piezoelectric biosensors. We analyzed challenges of biosensors for the monitoring of SEs and conclude the trends for the development of novel biosensors should pay attention to improve samples pretreatment efficiency, employ innovative nanomaterials, and develop portable instruments. This review provides new information and insightful commentary, important to the development and innovation of further detection methods for SEs in food samples.


Asunto(s)
Enfermedades Transmitidas por los Alimentos , Intoxicación Alimentaria Estafilocócica , Humanos , Staphylococcus aureus/genética , Intoxicación Alimentaria Estafilocócica/diagnóstico , Intoxicación Alimentaria Estafilocócica/epidemiología , Enterotoxinas/análisis , Espectrometría de Masas
12.
J Youth Adolesc ; 53(8): 1820-1831, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38600263

RESUMEN

Although metacognition plays a pivotal role in theoretical accounts of mind wandering, their longitudinal relationships have not yet been investigated during the important developmental period of early adolescence. This study aimed to examine the developmental trajectories of spontaneous and deliberate mind wandering and the dynamic associations between metacognition and two types of mind wandering in early adolescence. A sample of 4302 Chinese students beginning in Grade 4 (47.4% female; initial Mage = 9.84, SDage = 0.47) completed questionnaires on five occasions over 2.5 years. The results showed that deliberate mind wandering, but not spontaneous mind wandering, gradually increased from Grade 4 to Grade 6. Metacognition was negatively related to spontaneous mind wandering but positively related to deliberate mind wandering. These findings provide empirical evidence for theoretical viewpoints from both individual differences and developmental perspectives.


Asunto(s)
Atención , Metacognición , Humanos , Femenino , Masculino , Estudios Longitudinales , Adolescente , Niño , China , Encuestas y Cuestionarios , Desarrollo del Adolescente , Conducta del Adolescente/psicología , Estudiantes/psicología , Pensamiento
13.
J Youth Adolesc ; 53(2): 331-342, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37737939

RESUMEN

In cross-sectional research, subjective well-being and grit are found to be positively correlated. Their mutually reinforcing effects are particularly relevant for youth entering early adolescence because, during this developmental period, both well-being and grit have been shown to predict consequential outcomes later in life. However, their mutual relation has not yet been investigated in early adolescence. This study, therefore, examined the possibility of a virtuous cycle linking subjective well-being and grit during early adolescence. Self-report questionnaires of grit and subjective well-being were completed by N = 5291 children in China (47.6% girls; initial Mage = 9.69, SDage = 0.59) on six occasions over 3 academic years. In random-intercept cross-lagged panel models (RI-CLPMs), within-person changes in grit predicted within-person changes in subjective well-being 6 months later, and vice versa. Notably, analyses revealed an asymmetry in this cycle: paths from subjective well-being to grit were stronger and more reliable than the converse. Likewise, facet-level analyses showed that the predictive power of the perseverance component (of grit) and the affective component (of subjective well-being), respectively, was greater than the passion and cognitive components, respectively. These findings highlight the potential of boosting happiness for catalyzing positive youth development and, in addition, foreground the utility of studying these composite constructs at the facet level.


Asunto(s)
Emociones , Femenino , Niño , Humanos , Adolescente , Lactante , Masculino , Estudios Longitudinales , Estudios Transversales , Encuestas y Cuestionarios , Autoinforme
14.
J Youth Adolesc ; 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38740645

RESUMEN

Interest in socioeconomic differences in academic motivation has been longstanding. However, previous research has often treated both low- and high-SES students as homogenous groups. This study aims to address this gap by investigating the developmental trajectory profiles of mathematics motivation during early adolescence, with a focus on variations within and across SES groups. Multigroup latent class growth analysis was used on a sample of 3718 early adolescents in China (initial Mage was 9.40 ± 0.52 years; 48.0% girls) across 2 years from grades 4 through 6. The analysis identified three distinct self-determined mathematics motivation trajectory profiles within each SES group: a good-quality profile (i.e., initially high autonomous but low controlled), a high-quantity profile (i.e., initially high both autonomous and controlled), and a low-quantity profile (i.e., initially low both autonomous and controlled). A greater proportion of low-SES students were observed within the low-quantity profile than within the good-quality profile. The study found that the failure-is-enhancing view was a protective factor against two relatively maladaptive motivational trajectory profiles (i.e., high-quantity profile and low-quantity profile), irrespective of socioeconomic background. These findings emphasize the importance of implementing motivational interventions for early adolescents that consider both structural factors (e.g., socioeconomic backgrounds) and psychological factors (e.g., failure beliefs), to foster students' academic development.

15.
Funct Integr Genomics ; 23(2): 87, 2023 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-36932296

RESUMEN

Previous studies have shown that miR-322 regulates the functions of various stem cells. However, the role and mechanism of embryonic stem cell (ESCs) differentiation into cardiomyocytes remains unknown. Celf1 plays a vital role in stem cell differentiation and may be a potential target of miR-322 in ESCs' differentiation. We studied the function of miR-322An using mESCs transfected with lentivirus-mediated miR-322. RT-PCR results indicated that miR-322 increased NKX-2.5, MLC2V, and α-MHC mRNA expression, signifying that miR-322 might promote the differentiation of ESCs toward cardiomyocytes in vitro. The western blotting and immunofluorescence results confirmed this conclusion. In addition, the knockdown of miR-322 expression inhibited ESCs' differentiation toward cardiomyocytes in cultured ESCs in vitro. Western blotting results showed that miR-322 suppressed celf1 protein expression. Furthermore, Western blotting, RT-PCR, and immunofluorescence results showed that celf1 may inhibit ESCs' differentiation toward cardiomyocytes in vitro. Overall, the results indicate that miR-322 might promote ESCs' differentiation toward cardiomyocytes by regulating celf1 expression.


Asunto(s)
Proteínas CELF1 , MicroARNs , Células Madre Embrionarias de Ratones , Miocitos Cardíacos , Diferenciación Celular/genética , MicroARNs/genética , MicroARNs/metabolismo , Miocitos Cardíacos/metabolismo , Animales , Ratones , Proteínas CELF1/genética
16.
Chemistry ; 29(19): e202203361, 2023 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-36449331

RESUMEN

Conjugated polymers with high charge mobilities have drawn increasing attention in organic field-effect transistors (OFETs) in recent years. However, OFETs of conjugated polymers with high mobility and good device stability remain a challenge. In this article, we report a hyperbranched polymer approach to improve the charge mobility and device stability. Three hyperbranched diketopyrrolopyrrole-based polymers were designed and synthesized via linear alkyl side-chain linkers. The results show that 2D topological hyperbranched polymers form stable thin film microstructures, and thus improve the device stability, since the conjugated moiety is interconnected by linear alkyl chain. Besides, the incorporation of linear alkyl chain instead of branching alkyl one reduce steric hindrance, and improve the microstructure ordering as well as the charge mobility. Bar-coated OFETs result demonstrates that the devices mobilities and operational stabilities (bias stability and bending resistance) are both improved. All these indicate that hyperbranched polymer is a potential candidate for future application.

17.
Arch Biochem Biophys ; 743: 109645, 2023 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-37225009

RESUMEN

Deep second-degree burns heal slowly, and promoting the healing process is a focus of clinical research. Sestrin2 is a stress-inducible protein with antioxidant and metabolic regulatory effects. However, its role during acute dermal and epidermal re-epithelialization in deep second-degree burns is unknown. In this study, we aimed to explore the role and molecular mechanism of sestrin2 in deep second-degree burns as a potential treatment target for burn wounds. To explore the effects of sestrin2 on burn wound healing, we established a deep second-degree burn mouse model. Then we detected the expression of sestrin2 by western blot and immunohistochemistry after obtaining the wound margin of full-thickness burned skin. The effects of sestrin2 on burn wound healing were explored in vivo and in vitro through interfering sestrin2 expression using siRNAs or the small molecule agonist of sestrin2, eupatilin. We also investigated the molecular mechanism of sestrin2 in promoting burn wound healing by western blot and CCK-8 assay. Our in vivo and in vitro deep second-degree burn wound healing model demonstrated that sestrin2 was promptly induced at murine skin wound edges. The small molecule agonist of sestrin2 accelerated the proliferation and migration of keratinocytes, as well as burn wound healing. Conversely, the healing of burn wounds was delayed in sestrin2-deficient mice and was accompanied by the secretion of inflammatory cytokines as well as the suppression of keratinocyte proliferation and migration. Mechanistically, sestrin2 promoted the phosphorylation of the PI3K/AKT pathway, and inhibition of PI3K/AKT pathway abrogated the promoting role of sestrin2 in keratinocyte proliferation and migration. Therefore, sestrin2 plays a critical role in activation of the PI3K/AKT pathway to promote keratinocyte proliferation and migration, as well as re-epithelialization in the process of deep second-degree burn wound repair.


Asunto(s)
Quemaduras , Proteínas Proto-Oncogénicas c-akt , Animales , Ratones , Quemaduras/tratamiento farmacológico , Quemaduras/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Piel/metabolismo , Cicatrización de Heridas
18.
Langmuir ; 39(19): 6905-6913, 2023 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-37134210

RESUMEN

Covalent triazine frameworks (CTFs) obtained from the trimerization of aromatic nitriles are expected to be the preferred carrier for single-atom catalysts (SACs). Using density functional theory methods, the oxygen reduction reaction (ORR) performance of a series of 3d, 4d, and 5d transition metals supported on the 6N or 9N pore of the CTF system [M-CTF(6N) or M-CTF(9N)] is explored. At first, 32 kinds of M-CTF(6N) and M-CTF(9N) are screened out with high thermodynamic and electrochemical stability. The binding energy of ORR intermediates and the change of Gibbs free energy in each step of the ORR are calculated. The overpotential of Pd-CTF(6N) is the lowest, which is 0.38 V. Considering that the ORR activity of M-CTFs is mainly limited by the strong binding of *OH, M-CTF(6N) and M-CTF(9N) are further modified by the OH ligand, namely, M-OH-CTF(6N) and M-OH-CTF(9N). After being modified by the OH ligand, due to the weakened binding strength of *OH, all these screened M-CTFs exhibit better ORR activity. Among them, the η values of Cu-OH-CTF(6N), Pd-OH-CTF(6N), Rh-OH-CTF(6N), Ir-OH-CTF(6N), Rh-OH-CTF(9N), and Ir-OH-CTF(9N) are 0.39, 0.38, 0.24, 0.30, 0.31, and 0.33 V, respectively, which possess better ORR activity than the Pt(111) surface (η = 0.45 V). This work highlights the great potential of CTFs as an efficient carrier for SACs.

19.
Macromol Rapid Commun ; 44(23): e2300412, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37713720

RESUMEN

Polydiacetylenes, as a class of conjugated polymers with alternating conjugated C═C and C≡C bonds, have emerged as a promising probe material for biomedical Raman imaging, given their ultrastrong Raman scattering intensity. However, the relationship between the structure, especially the molecular length of polydiacetylenes, and their Raman scattering intensity remains unclear. In this work, a series of water-soluble polydiacetylenes, namely poly(deca-4,6-diynedioic acid) (PDDA) with different molecular weights (MWs), is prepared through controlled polymerization and degradation. The ultraviolet-visible (UV-vis) absorption spectroscopic and Raman spectroscopic studies on these polymers reveal that the Raman scattering intensity of PDDA increases nonlinearly with the MW. The MW-Raman scattering intensity relationship in the polymerization process is completely different from that in the degradation process. In contrast, the Raman scattering intensity increases more linearly with the maximal absorbance of the polymer, and the relationship between the Raman scattering intensity and the maximal absorbance of PDDA in the polymerization process is consistent with that in the degradation process. The Raman scattering intensity of PDDA hence exhibits a better dependence on the effective conjugation length of the polymer, which should guide the future design of conjugated polymers for Raman imaging applications.


Asunto(s)
Polímeros , Espectrometría Raman , Polímeros/química , Espectrometría Raman/métodos , Polímero Poliacetilénico/química , Peso Molecular
20.
BMC Geriatr ; 23(1): 650, 2023 10 11.
Artículo en Inglés | MEDLINE | ID: mdl-37821820

RESUMEN

OBJECTIVES: Klotho, an anti-aging protein, has been identified to control tissue inflammatory responses. The objective of this research is to determine the linkage between soluble Klotho (S-Klotho) level and systemic immune-inflammation index (SII). METHODS: Eligible participants with complete information of S-Klotho level and SII were selected from the National Health and Nutrition Examination Surveys (NHANES). Subsequently, weighted multivariate linear regression and subgroup analysis were carried out to evaluate the association. RESULTS: Totally, 11,108 adults with complete data on S-Klotho level, SII and other important covariates were included in final analysis. Multivariate liner regression revealed that high level of S-Klotho was associated with low level of SII after multivariate adjustments (ß=-0.08, 95%CI:-0.10- -0.05, P < 0.01). When classifying S-Klotho into tertiles, participants in S-Klotho tertile 3 (Q3) showed a decrease in SII level compared with those in the lowest tertile (Q1) (ß=-45.44, 95%CI:-64.41- -26.47, P < 0.01 ). The negative associations remained significant regardless of age and gender, and varied depending on smoking status and BMI subgroups. CONCLUSION: S-Klotho level was negatively related to SII after controlling for covariates. Further studies need to validate current findings and explore the fundamental mechanisms.


Asunto(s)
Envejecimiento , Inflamación , Humanos , Inflamación/diagnóstico , Encuestas Nutricionales
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