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1.
Adv Mater ; : e2313752, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38576272

RESUMO

Conventional conductive materials such as metals are crucial functional components of conductive systems in diverse electronic instruments. However, their severe intrinsic impedance mismatch with air dielectric causes strong reflection of incident electromagnetic waves, and the resulting low electromagnetic transmissivity typically interferes with surrounding electromagnetic signal communications in modern multifunction-integrated instruments. Herein, graphene glass fiber fabric (GGFF) that merges intrinsic electrical and electromagnetic properties of graphene with dielectric attributes and highly porous macrostructure of glass fiber fabric (GFF) is innovatively developed. Using a novel decoupling chemical vapor deposition growth strategy, high-quality and layer-limited graphene is prepared on noncatalytic nonmetallic GFF in a controlled manner; this is pivotal to realizing GGFF with the desired compatibility among high conductivity, low electromagnetic reflectivity, and high electromagnetic transmissivity. At the same sheet resistance over a wide range of values (250-3000 Ω·sq-1), the GGFF exhibits significantly lower electromagnetic reflectivity (by 0.42-0.51) and higher transmissivity (by 0.27-0.62) than those of its metal-based conductive counterpart (CuGFF). The material design strategy reported herein provides a constructive solution to eliminate the incompatibility between electrical conductivity and electromagnetic transmissivity faced by conventional conductive materials, spotlighting the applicability of GGFF in electric heating scenarios in radar, antenna, and stealth systems.

2.
Dalton Trans ; 53(19): 8264-8268, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38656395

RESUMO

Boron compounds have attracted the attention of chemists because of their unique catalytic properties and potential wider material applications. Although group 13 metal compounds, which are based on the bis-(benzoxazol-2-yl)-methane system (Box, ({NCOC6H4}2CH2)), have been reported in the last several years, boron containing Box compounds were still missing. Now we report their successful syntheses and spectroscopic characterisation in this work. The borane compound [({NCOC6H3}2CH)BH2] (1) and haloboranes [({NCOC6H3}2CH)BF2] (2), [({NCOC6H3}2CH)BCl2] (3) and [({NCOC6H3}2CH)BBr2] (4) were characterised in the solid state by single crystal X-ray diffraction and in solution by NMR techniques. In addition, the fluorescence properties of compounds 1-4 are communicated.

3.
Biomed Pharmacother ; 170: 116053, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38118349

RESUMO

BACKGROUND: Endoplasmic reticulum (ER) stress-induced nerve cell damage has been known to be a hallmark feature of Mn-induced parkinsonism pathogenesis. However, several compensatory machineries, such as unfolded protein response (UPR), autophagy, and immune response, play an essential role in this damage, and the underlying molecular mechanisms are poorly understood. METHODS: Neurobehavioral impairment was assessed using catwalk gait analysis and open field test. RNA-seq analyzed the differentially expressed genes (DEGs). TUNEL staining and immunohistochemical analysis evaluated the nerve cells apoptosis and microglial cell activation. Flow cytometry assay measured microglia M1/M2 polarization. Western blotting measured protein expression. Immunofluorescence staining was used to observe the target molecules' subcellular localization. RESULTS: The study revealed that Mn caused a reduction in motor capacity, nerve cell apoptosis, and microglia activation with an imbalance in M1/M2 polarization, coupled with NF-κB signaling and PERK signaling activation. 4-PBA pretreatment could counteract these effects, while 3-MA administration exacerbated them. Additionally, autophagy could be activated by Mn. This activation could be further upregulated by 4-PBA pretreatment, whereas it was suppressed under 3-MA administration. Mn also decreased inactive GSK-3ß, increased STAT3 signaling activation, and increased colocalization of GSK-3ß and STAT3. These effects were strengthened by 4-PBA pretreatment, while 3-MA administration reversed them. DISCUSSION: This study suggests that autophagy and M2 microglia polarization might be protective in Mn-induced ER stress damage, possibly through GSK-3ß-ULK1 autophagy signaling and STAT3 signaling activation.


Assuntos
Manganês , Microglia , Humanos , Manganês/farmacologia , Glicogênio Sintase Quinase 3 beta/metabolismo , Doenças Neuroinflamatórias , Estresse do Retículo Endoplasmático/fisiologia , Autofagia
4.
Angew Chem Int Ed Engl ; 63(9): e202317416, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38135667

RESUMO

Aminosilylene, comprising reactive NH- and Si(II) sites next to each other, is an intriguing class of compounds due to its ability to show diverse reactivity. However, stabilizing the reactive NH- group next to the free Si(II) atom is challenging and has not yet been achieved. Herein, we report the first examples of base stabilized free aminosilylenes Ar*NHSi(PhC(Nt Bu)2 ) (1 a) and Mes*NHSi(PhC(Nt Bu)2 ) (1 b) (Ar*=2,6-dibenzhydryl-4-methylphenyl and Mes*=2,4,6-tri-tert-butylphenyl), tolerating a NH- group next to the naked Si(II) atom. Remarkably, 1 a and 1 b exhibited interesting differences in their reactivity upon heating. With 1 a, an intramolecular C(sp3 )-H activation of one of the benzhydryl methine hydrogen atoms to the Si(II) atom produced the five-membered cyclic silazane 2. However, with 1 b, a rare 1,2-hydrogen shift to the Si(II) atom afforded a silanimine 3, with a hydride ligand attached to an unsaturated silicon atom. Further, the coordination capabilities of 1 a were also tested with Ru(II) and Fe(0) precursors. Treatments of 1 a with [Ru(η6 -p-cymene)Cl2 ]2 led to the isolation of a η6 -arene tethered complex [RuCl2 {Ar*NHSi(PhC(t BuN)2 )-κ1 -Si-η6 -arene}] (4), whereas with the Fe(CO)5 precursor a Fe(0) complex [Fe(CO)4 {Ar*NHSi(PhC(t BuN)2 )-κ1 -Si}] (5) was obtained. Density functional theory (DFT) calculations were conducted to shed light on the structural, bonding, and energetic aspects in 1-5.

5.
IUCrJ ; 10(Pt 6): 766-771, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37910142

RESUMO

Phosphorus exists in several different allotropes: white, red, violet and black. For industrial and academic applications, white phosphorus is the most important. So far, three polymorphs of white phosphorus, all consisting of P4 tetrahedra, have been described. Among these, ß-P4 crystallizes in the space group P1 and γ-P4 in the space group C2/m. α-P4 forms soft plastic crystals with a proposed structure in the cubic space group I43m with the lattice constant a = 18.51 (3) Å, consisting of 58 rotationally disordered tetrahedra and thus is similar to the structure of α-Mn. Here we present a new polymorph, δ-P4. It crystallizes as a sixfold twin with the cell dimensions a = 18.302 (2), b = 18.302 (2), c = 36.441 (3) Šin the space group P212121 with 29 P4 tetrahedra in the asymmetric unit. The arrangement resembles the structure of α-Mn, but δ-P4 differs from α-P4. DFT calculations show δ-P4 to be metastable at a similar energy level to that of γ-P4.

6.
Psychopharmacology (Berl) ; 240(9): 1865-1876, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37490132

RESUMO

BACKGROUND: Diabetic encephalopathy is manifested by cognitive dysfunction. Salidroside, a nature compound isolated from Rhodiola rosea L, has the effects of anti-inflammatory and antioxidant, hypoglycemic and lipid-lowering, improving insulin resistance, inhibiting cell apoptosis, and protecting neurons. However, the mechanism by which salidroside alleviates neuronal degeneration and improves learning and memory impairment in diabetic mice remains unclear. OBJECTIVE: To investigate the effects and mechanisms of salidroside on hippocampal neurons in streptozotocin-induced diabetic mice. MATERIALS AND METHODS: C57BL/6 mice were randomly divided into 4 groups to receive either sham (control group (CON)), diabetes mellitus (diabetes group (DM)), diabetes mellitus + salidroside (salidroside group (DM + SAL)), and diabetes mellitus + salidroside + phosphatidylinositol 3-kinase (PI3K) inhibitor LY294002 (diabetes mellitus + salidroside + LY294002 group (DM + SAL + LY294002)). After 12 weeks of diabetes onset, the cognitive behaviors were tested using Morris water maze. The number of hippocampal neurons was detected by Nissl staining. The expressions of PI3K, p-PI3K, Akt, p-Akt, GSK-3ß, p-GSK-3ß, cleaved caspase-3, caspase-3, Bax, Bcl-2, MAP2, and SYN in the hippocampus were detected by Western blot. Moreover, the expression of MAP2 and SYN in the hippocampus was further confirmed by immunofluorescence staining. RESULTS: Salidroside increased the time of diabetic mice in the platform quadrant and reduced the escape latency of diabetic mice. Salidroside also increased the expression of p-PI3K, p-Akt, p-GSK-3ß, MAP2, SYN, Bcl-2, while suppressed the expression of cleaved caspase-3, caspase3, and Bax in the DM + SAL group compared with the DM group (P < 0.05). The Nissl staining showed that the number of hippocampus neurons in the DM + SAL group was increased with the intact, compact, and regular arrangement, compared with the DM groups (P < 0.05). Interestingly, the protective effects of salidroside on diabetic cognitive dysfunction, hippocampal morphological alterations, and protein expressions were abolished by inhibition of PI3K with LY294002. CONCLUSIONS: Salidroside exerts neuroprotective properties in diabetic cognitive dysfunction partly via activating the PI3K/Akt/GSK-3ß signaling pathway.


Assuntos
Encefalopatias , Hipocampo , Hipoglicemia , Fármacos Neuroprotetores , Animais , Camundongos , Apoptose/efeitos dos fármacos , Proteína X Associada a bcl-2/metabolismo , Caspase 3/metabolismo , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/metabolismo , Glicogênio Sintase Quinase 3 beta/metabolismo , Hipocampo/efeitos dos fármacos , Hipocampo/patologia , Camundongos Endogâmicos C57BL , Neurônios , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Fosfatidilinositol 3-Quinase/metabolismo , Fosfatidilinositol 3-Quinase/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Fosfatidilinositol 3-Quinases/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Transdução de Sinais , Encefalopatias/tratamento farmacológico , Hipoglicemia/tratamento farmacológico
7.
Materials (Basel) ; 16(10)2023 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-37241483

RESUMO

The various forms of cellulose-based materials possess high mechanical and thermal stabilities, as well as three-dimensional open network structures with high aspect ratios capable of incorporating other materials to produce composites for a wide range of applications. Being the most prevalent natural biopolymer on the Earth, cellulose has been used as a renewable replacement for many plastic and metal substrates, in order to diminish pollutant residues in the environment. As a result, the design and development of green technological applications of cellulose and its derivatives has become a key principle of ecological sustainability. Recently, cellulose-based mesoporous structures, flexible thin films, fibers, and three-dimensional networks have been developed for use as substrates in which conductive materials can be loaded for a wide range of energy conversion and energy conservation applications. The present article provides an overview of the recent advancements in the preparation of cellulose-based composites synthesized by combining metal/semiconductor nanoparticles, organic polymers, and metal-organic frameworks with cellulose. To begin, a brief review of cellulosic materials is given, with emphasis on their properties and processing methods. Further sections focus on the integration of cellulose-based flexible substrates or three-dimensional structures into energy conversion devices, such as photovoltaic solar cells, triboelectric generators, piezoelectric generators, thermoelectric generators, as well as sensors. The review also highlights the uses of cellulose-based composites in the separators, electrolytes, binders, and electrodes of energy conservation devices such as lithium-ion batteries. Moreover, the use of cellulose-based electrodes in water splitting for hydrogen generation is discussed. In the final section, we propose the underlying challenges and outlook for the field of cellulose-based composite materials.

8.
J Colloid Interface Sci ; 647: 43-51, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37244175

RESUMO

Hexagonal boron nitride (BN) is an attractive filler candidate for thermal interface materials, but the thermal conductivity enhancement is limited by the anisotropic thermal conductivity of BN and disordered thermal pathways in the polymer matrix. Herein, a facile and economic ice template method is proposed, wherein BN modified by tannic acid (BN-TA) directly self-assemble to form vertically aligned nacre-mimetic scaffold without additional binders and post-treatment. The effects of the BN slurry concentration and the ratio of BN/TA on three-dimensional (3D) skeleton morphology are fully investigated. The corresponding polydimethylsiloxane (PDMS) composite via vacuum-impregnation achieves a high through-plane thermal conductivity of 3.8 W/mK at a low filler loading of 18.7 vol%, which is 2433% and 100% higher than that of pristine PDMS and the PDMS composite with randomly distributed BN-TA, respectively. The finite element analysis results theoretically demonstrate the superiority of the highly longitudinally ordered 3D BN-TA skeleton in axial heat transfer. Additionally, 3D BN-TA/PDMS exhibits excellent practical heat dissipation capability, lower thermal expansion coefficient, and enhanced mechanical properties. This strategy offers an anticipated perspective for developing high-performance thermal interface materials to address the thermal challenges of modern electronics.

9.
Ecotoxicol Environ Saf ; 256: 114872, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37027942

RESUMO

Manganese (Mn), as one of the environmental risk factors for Parkinson's disease (PD), has been widely studied. Though autophagy dysfunction and neuroinflammation mainly are responsible for the causative issue of Mn neurotoxicity, the molecular mechanism of parkinsonism caused by Mn has not been explored clearly. The results of in vivo and in vitro experiments showed that overexposure to Mn caused neuroinflammation impairment and autophagy dysfunction, accompanied by the increase of IL-1ß, IL-6, and TNF-α mRNA expression, and nerve cell apoptosis, microglia cell activation, NF-κB activation, poor neurobehavior performance. This is due to Mn-induced the downregulation of SIRT1. Upregulation of SIRT1 in vivo and in vitro could alleviate Mn-induced autophagy dysfunction and neuroinflammation, yet these beneficial effects were abolished following 3-MA administration. Furthermore, we found that Mn interfered with the acetylation of FOXO3 by SIRT1 in BV2 cells, leading to a decrease in the nuclear translocation of FOXO3, and its binding of LC3B promoter and transcription activity. This could be antagonized by the upregulation of SIRT1. Finally, it is proved that SIRT1/FOXO3-LC3B autophagy signaling involves in Mn-induced neuroinflammation impairment.


Assuntos
Manganês , Doenças Neuroinflamatórias , Autofagia , Proteína Forkhead Box O3/metabolismo , Manganês/metabolismo , Microglia , Sirtuína 1/metabolismo , Animais , Camundongos
10.
Acta Diabetol ; 60(5): 631-644, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36717397

RESUMO

BACKGROUND: CD4 + T helper (Th)22 cells play a regulatory role in autoimmune diseases such as type 1 diabetes mellitus. The Th22-related cytokine interleukin (IL)-22, the expression of which is increased in diabetes mellitus (DM), can act as a neurotrophic factor to protect neurons from apoptosis. Paradoxically, neuronal apoptosis and learning and memory decline occur in DM. In this study, we investigated the relationship between IL-22 and its receptors IL-22Rα1 and IL-22 binding protein (IL-22BP, a soluble inhibitor of IL-22) in diabetic encephalopathy (DE) and the effects of IL-22 on hippocampal neurons, learning and memory. METHODS: A C57BL/6 mouse model of diabetes was constructed by intraperitoneal injection of streptozotocin. The mice were randomly divided into 4 groups: the control group, diabetes group, diabetes + recombinantIL-22 (rIL-22) group and diabetes + IL-22BP group. The Morris water maze test was used to evaluate learning and memory, the expression of IL-22 was measured by ELISA, and Evans Blue staining was used to evaluate blood-brain barrier permeability. Quantitative reverse transcription polymerase chain reaction (RT-qPCR) was used to measure the mRNA expression of IL-22 and IL-22Rα1 in the hippocampus. The morphology and number of hippocampal neurons were assessed by Nissl staining, and TUNEL staining was used to detect hippocampal neuronal apoptosis. Immunofluorescence was used to analyze IL-22Rα1 expression and localization in hippocampus, and Western blotting was used to evaluate the expression of IL-22, IL-22Rα1, IL-22BP, and the apoptosis related proteins Caspase-3 and C-caspase-3. RESULTS: Compared with those in the control group, mice in the diabetes group showed cognitive decline; apoptosis of hippocampal neurons; increased expression of hippocampal Caspase-3, C-Caspase-3, IL-22, IL-22Rα1, and IL-22BP; and a decreased IL-22/IL-22BP ratio. Learning and memory were improved, neuronal apoptosis was attenuated, IL-22Rα1 expression and the IL-22/IL-22BP ratio were increased, and caspase-3 and C-caspase-3 expression was decreased in the rIL-22-treated group compared with the diabetes group. IL-22BP treatment aggravated diabetic cognitive dysfunction and pathological alterations in the hippocampus, decreased the IL-22/IL-22BP ratio, and increased the expression of caspase-3 and C-caspase-3 in mice with diabetes. CONCLUSION: A decrease in the IL-22/IL-22BP ratio plays an important role in diabetic cognitive dysfunction, and rIL-22 can effectively alleviate DE. Herein, we shed light on the interaction between IL-22 and IL-22BP as therapeutic targets for DM.


Assuntos
Disfunção Cognitiva , Diabetes Mellitus Experimental , Ratos , Camundongos , Animais , Caspase 3/metabolismo , Ratos Sprague-Dawley , Diabetes Mellitus Experimental/metabolismo , Camundongos Endogâmicos C57BL , Disfunção Cognitiva/etiologia , Interleucinas/genética , Interleucinas/farmacologia , Interleucinas/uso terapêutico , Apoptose , Interleucina 22
11.
ACS Appl Mater Interfaces ; 15(5): 7578-7591, 2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36716404

RESUMO

The effective integration of multiple functions into electromagnetic wave-absorbing (EWA) materials is the future development direction but remains a huge challenge. A rational selection of components and the design of structures can make the material have excellent EWA performance and heat dissipation. Herein, the core-shell structured boron nitride@nitrogen-doped carbon (BN@NC) is prepared by using waterborne polyurethane (WPU) as the carbon source via a facile pyrolysis treatment process, where NC is used as the conductive loss shell, and BN serves as an impedance matching core and dominant heat transfer media. As a result, the BN@NC-900 filled with paraffin wax yields a minimum reflection loss of -42.2 dB at 2.2 mm and an effective absorbing bandwidth of 4.48 GHz at 1.8 mm, and its thermal conductivity reaches up to 0.92 W/m·K in epoxy resin. Most importantly, flexible BN@NC/WPU films are prepared and simultaneously achieve the dual-functional capability of efficiently dissipating heat and electromagnetic waves (-50.0 dB). Besides, an attractive multiband absorption feature (>99%) from C to Ku bands is realized and a strong absorbing over -27.0 dB at the S band (2.88 GHz) is even achieved. This study may pave a new route for the rational design of multifunctional EWA materials.

12.
Adv Mater ; 35(18): e2209897, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36720106

RESUMO

Solar heating and radiative cooling techniques have been proposed for passive space thermal management to reduce the global energy burden. However, the currently used single-function envelope/coating materials can only achieve static temperature regulation, presenting limited energy savings and poor adaption to dynamic environments. In this study, a sandwich-structured fabric, composed of vertical graphene, graphene glass fiber fabric, and polyacrylonitrile nanofibers is developed, with heating and cooling functions integrated through multiband, synergistic, (solar spectrum and mid-infrared ranges) and asymmetric optical modulations on two sides of the fabric. The dual-function fabric demonstrates high adaption to the dynamic environment and superior performance in a zero-energy-input temperature regulation. Furthermore, it demonstrates ≈15.5 and ≈31.1 MJ m-2 y-1 higher annual energy savings compared to those of their cooling-only and heating-only counterparts, corresponding to ≈173.7 MT reduction in the global CO2 emission. The fabric exhibits high scalability for batch manufacturing with commercially abundant raw materials and facile technologies, providing a favorable guarantee of its mass production and use.

13.
Neuroscience ; 512: 47-58, 2023 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-36509381

RESUMO

Diabetes is frequently accompanied by cognitive impairment with insidious onset, and progressive cognitive and behavioral changes. ß-1, 3-galactosyltransferase 2 (B3galt2) contributes to glycosylation, showing a clue for neuronal apoptosis, proliferation and differentiation. However, the role of B3galt2 in diabetic cognitive dysfunction (DCD) has not been investigated. In the present study, we aimed to explore the role of B3galt2 in DCD. Additionally, the potential therapeutic effects of salidroside on DCD was also explored. Diabetic C57BL/6J mice showed cognitive dysfunction together with down-regulated B3galt2. Overexpression of B3galt2 reversed the cognitive decline of diabetic C57BL/6J. Moreover, cognitive impairment was aggravated in B3galt2+/- diabetic mice compared with C57BL/6J diabetic mice. Immunohistochemistry fluorescence indicated that B3galt2 and F3/Contactin were co-localized in the hippocampal regions. Importantly, the expression of F3/Contactin can be regulated by the manipulation of B3galt2, overexpression of which assuaged hippocampal neuronal damage, protected the synapsin, and reduced neuronal apoptosis in diabetic mice. Interestingly, SAL alleviated DCD and reversed the expression of B3galt2 in diabetic C57BL/6J mice. These findings indicate that inhibition of B3galt2/F3/Contactin pathway contributes to DCD, and participates in SAL reversed DCD.


Assuntos
Disfunção Cognitiva , Diabetes Mellitus Experimental , Camundongos , Animais , Contactina 1/metabolismo , Camundongos Endogâmicos C57BL , Contactinas , Transdução de Sinais
14.
Int J Mol Sci ; 23(19)2022 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-36232647

RESUMO

The misuse and mismanagement of antibiotics have made the treatment of bacterial infections a challenge. This challenge is magnified when bacteria form biofilms, which can increase bacterial resistance up to 1000 times. It is desirable to develop anti-infective materials with antibacterial activity and no resistance to drugs. With the rapid development of nanotechnology, anti-infective strategies based on metal and metal oxide nanomaterials have been widely used in antibacterial and antibiofilm treatments. Here, this review expounds on the state-of-the-art applications of metal and metal oxide nanomaterials in bacterial infective diseases. A specific attention is given to the antibacterial mechanisms of metal and metal oxide nanomaterials, including disrupting cell membranes, damaging proteins, and nucleic acid. Moreover, a practical antibiofilm mechanism employing these metal and metal oxide nanomaterials is also introduced based on the composition of biofilm, including extracellular polymeric substance, quorum sensing, and bacteria. Finally, current challenges and future perspectives of metal and metal oxide nanomaterials in the anti-infective field are presented to facilitate their development and use.


Assuntos
Anti-Infecciosos , Infecções Bacterianas , Nanoestruturas , Ácidos Nucleicos , Antibacterianos/uso terapêutico , Anti-Infecciosos/uso terapêutico , Bactérias/metabolismo , Infecções Bacterianas/tratamento farmacológico , Infecções Bacterianas/microbiologia , Biofilmes , Matriz Extracelular de Substâncias Poliméricas , Humanos , Ácidos Nucleicos/metabolismo , Óxidos/metabolismo , Plâncton
15.
Cell Tissue Res ; 390(3): 367-383, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36201050

RESUMO

T helper 22 (Th22) cells have been implicated in diabetic retinopathy (DR), but it remains unclear whether Th22 cells involve in the pathogenesis of DR. To investigate the role of Th22 cells in DR mice, the animal models were established by intraperitoneal injection of STZ and confirmed by fundus fluorescein angiography and retinal haematoxylin-eosin staining. IL-22BP was administered by intravitreal injection. IL-22 level was measured by ELISA in vivo and in vitro. The expression of IL-22Rα1 in the retina was assessed by immunofluorescence. We assessed GFAP, VEGF, ICAM-1, inflammatory-associated factors and the integrity of blood-retinal barrier in control, DR, IL-22BP, and sham group. Müller cells were co-cultured with Th22 cells, and the expression of the above proteins was measured by immunoblotting. Plasmid transfection technique was used to silence Act1 gene in Müller cells. Results in vivo and in vitro indicated that Th22 cells infiltrated into the DR retinal and IL-22Rα1 expressed in Müller cells. Th22 cells promoted Müller cells activation and inflammatory factor secretion by secreting IL-22 compared with high-glucose stimulation alone. In addition, IL-22BP ameliorated the pathological alterations of the retina in DR. Inhibition of the inflammatory signalling cascade through Act1 knockdown alleviated DR-like pathology. All in all, the results suggested that Th22 cells infiltrated into the retina and secreted IL-22 in DR, and then IL-22 binding with IL-22Rα1 activated the Act1/TRAF6 signal pathway, and promoted the inflammatory of Müller cells and involved the pathogenesis of DR.


Assuntos
Diabetes Mellitus Experimental , Retinopatia Diabética , Camundongos , Animais , Células Ependimogliais/patologia , Fator 6 Associado a Receptor de TNF/metabolismo , Diabetes Mellitus Experimental/patologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Retina/metabolismo
16.
Adv Sci (Weinh) ; 9(36): e2204624, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36285805

RESUMO

Heat is abundantly available from various sources including solar irradiation, geothermal energy, industrial processes, automobile exhausts, and from the human body and other living beings. However, these heat sources are often overlooked despite their abundance, and their potential applications remain underdeveloped. In recent years, important progress has been made in the development of high-performance thermoelectric materials, which have been extensively studied at medium and high temperatures, but less so at near room temperature. Silver-based chalcogenides have gained much attention as near room temperature thermoelectric materials, and they are anticipated to catalyze tremendous growth in energy harvesting for advancing internet of things appliances, self-powered wearable medical systems, and self-powered wearable intelligent devices. This review encompasses the recent advancements of thermoelectric silver-based chalcogenides including binary and multinary compounds, as well as their hybrids and composites. Emphasis is placed on strategic approaches which improve the value of the figure of merit for better thermoelectric performance at near room temperature via engineering material size, shape, composition, bandgap, etc. This review also describes the potential of thermoelectric materials for applications including self-powering wearable devices created by different approaches. Lastly, the underlying challenges and perspectives on the future development of thermoelectric materials are discussed.


Assuntos
Prata , Dispositivos Eletrônicos Vestíveis , Humanos , Catálise , Engenharia , Temperatura Alta
17.
Front Cardiovasc Med ; 9: 821672, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35391838

RESUMO

Backgrounds and Objectives: Drug-coated balloons (DCBs) have shown promising benefits in improving the outcomes for patients with peripheral artery disease. Several randomized clinical trials have reported that paclitaxel-coated balloon significantly reduce the rates of restenosis and the need for reintervention in comparison with regular balloon angioplasty. Due to the differences in excipients, paclitaxel dose, and coating techniques, variable clinical outcomes have been observed with different DCBs. In this study, we aimed to evaluate the safety and efficacy of a novel ZENFlow carrier-free DCB in the treatment of femoropopliteal artery occlusive disease. Methods: In this randomized controlled trial conducted at 15 sites, 192 patients with Rutherford class 3-5 were randomly assigned into two groups: drug-coated balloon group and percutaneous transluminal angioplasty group. The primary endpoint was a late lumen loss at 6 months based on blinded angiographic core laboratory evaluations, and the secondary endpoints included primary patency rate, binary restenosis, clinically driven target lesion revascularization, ankle-brachial index, Rutherford class change, and major adverse events. Results: In this multicenter trial, 93 patients received DCB angioplasty, whereas 99 patients underwent regular balloon angioplasty. The late lumen loss at 6-month follow-up was 0.50 ± 0.82 and 1.69 ± 0.87 mm in the drug-coated balloon and percutaneous transluminal angioplasty groups, respectively (p < 0.001). During the 12-month follow-up period, the drug-coated balloon group showed a significantly higher primary patency rate (54 vs. 31.3%, p = 0.009) and markedly lower rates of target vessel restenosis (22.1 vs. 64.3%, p < 0.001) and clinically driven target lesion revascularization rate (5.4 vs. 19.2%, p = 0.006) than the percutaneous transluminal angioplasty group. Compared with the percutaneous transluminal angioplasty group, the drug-coated balloon group had significant improvements in the ankle-brachial index and Rutherford class. The all-cause mortality rate was comparable, and no device-related deaths occurred in either groups. Conclusions: Balloon angioplasty using a ZENFlow carrier-free drug-coated balloon is a safe and effective treatment method for femoropopliteal artery lesions. This novel drug-coated balloon catheter achieved satisfactory early and 1-year outcomes in this trial. Clinical Trial Registration: https://clinicaltrials.gov, identifier: NCT03844724.

18.
J Colloid Interface Sci ; 619: 388-398, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35398769

RESUMO

HYPOTHESIS: The practical applications of boron nitride nanosheet (BNNS) are dramatically limited by the harsh exfoliation and surface functionalization conditions due to the hydrophobic and chemically inert nature. This issue can be improved by selecting efficient modifiers with hydrophilic groups. EXPERIMENTS: A green and scalable amino acid-assisted ball milling method is presented to exfoliate and functionalize BNNS simultaneously. The different interactions between BNNS and four amino acids (tryptophan (Trp), phenylalanine (Phe), arginine (Arg), lysine (Lys)) are thoroughly investigated to rationalize the thermal and mechanical properties of their corresponding epoxy (EP) composites. FINDING: Trp and Phe display higher functionalization degree and dispersibility of BNNS than Arg and Lys thanks to the additional π-π interactions between the aromatic groups and BNNS. Moreover, both BNNS-Trp/EP and BNNS-Phe/EP exhibit higher cross-plane thermal conductivity of 2.1 and 1.96 W m-1 K-1 at 30 wt% filler loading. In addition, the mechanical strengths of all these amino acids functionalized BNNS filled epoxy composites are significantly enhanced due to stronger interfacial interactions between fillers and epoxy matrix. Thus, this work paves the way for the facile mass production of functionalized BNNS and expedites their applications in thermal interface materials of electronic components.


Assuntos
Aminoácidos , Compostos de Boro , Compostos de Boro/química , Resinas Epóxi , Condutividade Térmica
19.
ACS Nano ; 16(2): 2577-2584, 2022 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-35107258

RESUMO

Radiant heating, as a significant thermal management technique, is best known for its high thermal effect, media-free operation, good penetration, and compatibility for different heated shapes. To promote sustainable development in this area, developing advanced infrared radiation material is in high demand. In this work, a lightweight, flexible dual-emitter infrared electrothermal material, graphene glass fiber (GGF), is developed by chemical vapor deposition (CVD) method, with both graphene and glass fiber as the radiation elements. Large-area GGF fabric (GGFF) exhibits wavelength-independent high infrared emissivity (0.92) and thermal radiation efficiency (79.4%), as well as ultrafast electrothermal response (190.7 °C s-1 at 9.30 W cm-2) and uniform heating temperature. The superior radiant heating capability of GGFF to traditional alloy heating wires can achieve 33.3% energy saving. GGF can promote the development of efficient and energy-saving heat management technology.

20.
ACS Appl Mater Interfaces ; 12(41): 46549-46556, 2020 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-32964711

RESUMO

Nd2Fe14B has attracted intensive attention because of its excellent magnetic properties since 1980s. However, large demands for the expensive rare earth (mainly refers to Nd/Pr/Dy) limit its wider applications. Investigations of Ce-doped Nd2Fe14B have been attempted recently and multi-main-phase (MMP) (Nd,Ce)2Fe14B provides a promising way for the preparation of high-performance Ce-doped permanent magnets even though the inner mechanism has not been absolutely understood. We synthesized Ce-doped Nd2Fe14B nanostructures by the chemical method and successfully realized the obvious property enhancement of the MMP sample compared with that of the single-main-phase one. The coercivity of the MMP nanostructures is nearly 4.5 kOe with a remanence ratio of 0.36 before magnetic orientation, which is much larger than that of the SMP sample (1.7 kOe and 0.21), respectively. The property enhancement mechanism of the MMP sample analyzed mainly by first-order reversal curves could be concluded in three aspects: first, the content of α-Fe will be decreased; hence, the difficulty of the magnetic nucleation is increased. Second, the exchange coupling effect between the adjacent magnetic structures will be strengthened significantly. Last, the grain boundary phases with various magnetic features are formed, enhancing the magnetic pinning effect and specially tuning the inner interactions. This work is helpful for the deeper understanding of the property enhancement mechanism in MMP nanomagnets and provides an instructive way for the effective design and preparation of high-performance MMP Ce-doped Nd2Fe14B nanomagnets.

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