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1.
Nature ; 632(8026): 782-787, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39143208

RESUMO

Hot-carrier transistors are a class of devices that leverage the excess kinetic energy of carriers. Unlike regular transistors, which rely on steady-state carrier transport, hot-carrier transistors modulate carriers to high-energy states, resulting in enhanced device speed and functionality. These characteristics are essential for applications that demand rapid switching and high-frequency operations, such as advanced telecommunications and cutting-edge computing technologies1-5. However, the traditional mechanisms of hot-carrier generation are either carrier injection6-11 or acceleration12,13, which limit device performance in terms of power consumption and negative differential resistance14-17. Mixed-dimensional devices, which combine bulk and low-dimensional materials, can offer different mechanisms for hot-carrier generation by leveraging the diverse potential barriers formed by energy-band combinations18-21. Here we report a hot-emitter transistor based on double mixed-dimensional graphene/germanium Schottky junctions that uses stimulated emission of heated carriers to achieve a subthreshold swing lower than 1 millivolt per decade beyond the Boltzmann limit and a negative differential resistance with a peak-to-valley current ratio greater than 100 at room temperature. Multi-valued logic with a high inverter gain and reconfigurable logic states are further demonstrated. This work reports a multifunctional hot-emitter transistor with significant potential for low-power and negative-differential-resistance applications, marking a promising advancement for the post-Moore era.


Assuntos
Temperatura Alta , Transistores Eletrônicos , Grafite/química
2.
Proc Natl Acad Sci U S A ; 121(34): e2320257121, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39150784

RESUMO

Lysosomal degradation pathways coordinate the clearance of superfluous and damaged cellular components. Compromised lysosomal degradation is a hallmark of many degenerative diseases, including lysosomal storage diseases (LSDs), which are caused by loss-of-function mutations within both alleles of a lysosomal hydrolase, leading to lysosomal substrate accumulation. Gaucher's disease, characterized by <15% of normal glucocerebrosidase function, is the most common LSD and is a prominent risk factor for developing Parkinson's disease. Here, we show that either of two structurally distinct small molecules that modulate PIKfyve activity, identified in a high-throughput cellular lipid droplet clearance screen, can improve glucocerebrosidase function in Gaucher patient-derived fibroblasts through an MiT/TFE transcription factor that promotes lysosomal gene translation. An integrated stress response (ISR) antagonist used in combination with a PIKfyve modulator further improves cellular glucocerebrosidase activity, likely because ISR signaling appears to also be slightly activated by treatment by either small molecule at the higher doses employed. This strategy of combining a PIKfyve modulator with an ISR inhibitor improves mutant lysosomal hydrolase function in cellular models of additional LSD.


Assuntos
Fibroblastos , Glucosilceramidase , Doenças por Armazenamento dos Lisossomos , Lisossomos , Fosfatidilinositol 3-Quinases , Humanos , Fosfatidilinositol 3-Quinases/metabolismo , Lisossomos/metabolismo , Lisossomos/efeitos dos fármacos , Glucosilceramidase/metabolismo , Glucosilceramidase/genética , Fibroblastos/metabolismo , Fibroblastos/efeitos dos fármacos , Doenças por Armazenamento dos Lisossomos/tratamento farmacológico , Doenças por Armazenamento dos Lisossomos/genética , Doenças por Armazenamento dos Lisossomos/metabolismo , Doença de Gaucher/tratamento farmacológico , Doença de Gaucher/genética , Doença de Gaucher/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase/farmacologia
3.
Mol Psychiatry ; 2024 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-39003414

RESUMO

Neuroligin-3 (Nlgn3) is an autism-associated cell-adhesion molecule that interacts with neurexins and is robustly expressed in both neurons and astrocytes. Neuronal Nlgn3 is an essential regulator of synaptic transmission but the function of astrocytic Nlgn3 is largely unknown. Given the high penetrance of Nlgn3 mutations in autism and the emerging role of astrocytes in neuropsychiatric disorders, we here asked whether astrocytic Nlgn3 might shape neural circuit properties in the cerebellum similar to neuronal Nlgn3. Imaging of tagged Nlgn3 protein produced by CRISPR/Cas9-mediated genome editing showed that Nlgn3 is enriched in the cell body but not the fine processes of cerebellar astrocytes (Bergmann glia). Astrocyte-specific knockout of Nlgn3 did not detectably alter the number of synapses, synaptic transmission, or astrocyte morphology in mouse cerebellum. However, spatial transcriptomic analyses revealed a significant shift in gene expression among multiple cerebellar cell types after the deletion of astrocytic Nlgn3. Hence, in contrast to neuronal Nlgn3, astrocytic Nlgn3 in the cerebellum is not involved in shaping synapses but may modulate gene expression in specific brain areas.

4.
Artigo em Inglês | MEDLINE | ID: mdl-38761998

RESUMO

BACKGROUND: Previous studies implied that local M2 polarization of macrophage promoted mucosal edema and exacerbated TH2 type inflammation in chronic rhinosinusitis with nasal polyps (CRSwNP). However, the specific pathogenic role of M2 macrophages and the intrinsic regulators in the development of CRS remains elusive. OBJECTIVE: We sought to investigate the regulatory role of SIRT5 in the polarization of M2 macrophages and its potential contribution to the development of CRSwNP. METHODS: Real-time reverse transcription-quantitative PCR and Western blot analyses were performed to examine the expression levels of SIRT5 and markers of M2 macrophages in sinonasal mucosa samples obtained from both CRS and control groups. Wild-type and Sirt5-knockout mice were used to establish a nasal polyp model with TH2 inflammation and to investigate the effects of SIRT5 in macrophage on disease development. Furthermore, in vitro experiments were conducted to elucidate the regulatory role of SIRT5 in polarization of M2 macrophages. RESULTS: Clinical investigations showed that SIRT5 was highly expressed and positively correlated with M2 macrophage markers in eosinophilic polyps. The expression of SIRT5 in M2 macrophages was found to contribute to the development of the disease, which was impaired in Sirt5-deficient mice. Mechanistically, SIRT5 was shown to enhance the alternative polarization of macrophages by promoting glutaminolysis. CONCLUSIONS: SIRT5 plays a crucial role in promoting the development of CRSwNP by supporting alternative polarization of macrophages, thus providing a potential target for CRSwNP interventions.

5.
Analyst ; 149(5): 1489-1495, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38314794

RESUMO

A novel cyclooxygenase-2 (COX-2) targeted H2S-activated cancer-specific fluorescent probe, namely, COX2-H2S, was designed and synthesized, with naphthalimide as the fluorophore and indomethacin as the targeting group. This H2S-sensing probe was developed to differentiate tumor cells from normal cells and was tested in living cells, Caenorhabditis elegans (C. elegans), and zebrafish. The probe could successfully be used for imaging endogenous and exogenous H2S in living cells, demonstrating high sensitivity and specificity and strong anti-interference. COX2-H2S had the ability to not only discern cancer cells from normal cells but also specifically recognize 9L/lacZ cells from other glioblastoma cells (U87-MG and LN229). It could also be successfully applied for the fluorescent live imaging of H2S in both C. elegans and zebrafish.


Assuntos
Sulfeto de Hidrogênio , Neoplasias , Animais , Humanos , Caenorhabditis elegans , Ciclo-Oxigenase 2 , Corantes Fluorescentes , Sulfeto de Hidrogênio/análise , Neoplasias/diagnóstico por imagem , Imagem Óptica/métodos , Peixe-Zebra , Linhagem Celular Tumoral
6.
Bioorg Chem ; 144: 107111, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38218068

RESUMO

To mine fascinating molecules from the rhizomes of Atractylodes chinensis, the known molecular formula of atrachinenin A was used as a bait to search LC-HRMS data in different subfractions. Sixteen new meroterpenoids, atrachinenins D-S (1-16) including three unprecedented carbon skeletons (1-5) and eleven new oxygen-bridged hybrids (6-16) were obtained by the targeted isolation. Their structures and absolute configurations were elucidated by the spectroscopic data and electronic circular dichroism (ECD) calculations. The isolated compounds were evaluated for their inhibitory activity of NO production and compounds 1, 4, 8, and 13 showed moderate anti-inflammatory activity. The proposed biosynthetic pathways of 1-5 were also discussed.


Assuntos
Atractylodes , Atractylodes/química , Hidroquinonas , Anti-Inflamatórios , Dicroísmo Circular , Estrutura Molecular
7.
Acta Pharmacol Sin ; 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38914677

RESUMO

Mesenchymal stem cell-derived extracellular vesicles (MSC-EVs) have obvious advantages over MSC therapy. But the strong procoagulant properties of MSC-EVs pose a potential risk of thromboembolism, an issue that remains insufficiently explored. In this study, we systematically investigated the procoagulant activity of large EVs derived from human umbilical cord MSCs (UC-EVs) both in vitro and in vivo. UC-EVs were isolated from cell culture supernatants. Mice were injected with UC-EVs (0.125, 0.25, 0.5, 1, 2, 4 µg/g body weight) in 100 µL PBS via the tail vein. Behavior and mortality were monitored for 30 min after injection. We showed that these UC-EVs activated coagulation in a dose- and tissue factor-dependent manner. UC-EVs-induced coagulation in vitro could be inhibited by addition of tissue factor pathway inhibitor. Notably, intravenous administration of high doses of the UC-EVs (1 µg/g body weight or higher) led to rapid mortality due to multiple thrombus formations in lung tissue, platelets, and fibrinogen depletion, and prolonged prothrombin and activated partial thromboplastin times. Importantly, we demonstrated that pulmonary thromboembolism induced by the UC-EVs could be prevented by either reducing the infusion rate or by pre-injection of heparin, a known anticoagulant. In conclusion, this study elucidates the procoagulant characteristics and mechanisms of large UC-EVs, details the associated coagulation risk during intravenous delivery, sets a safe upper limit for intravenous dose, and offers effective strategies to prevent such mortal risks when high doses of large UC-EVs are needed for optimal therapeutic effects, with implications for the development and application of large UC-EV-based as well as other MSC-EV-based therapies.

8.
Graefes Arch Clin Exp Ophthalmol ; 262(7): 2189-2198, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38349421

RESUMO

PURPOSE: To compare corneal haze between active ulcer and healed scarring using a Scheimpflug densitometry. MATERIALS AND METHODS: A prospective longitudinal study enrolled 30 patients (30 eyes) with ulcerative keratitis (UK). Each subject's corneal optical density (COD) was measured with a Scheimpflug corneal densitometry, Pentacam® AXL (Oculus GmbH, Wetzlar, Germany), at the active ulcerative and complete scarring stage. The COD data were analyzed through distinct methods (inbuilt, sorted annular partitions, and ulcer-matching densitometric maps). We compared different CODs to select the better index for clinically monitoring the transition from corneal ulceration to healed scar. RESULTS: The CODs of the periphery (P = 0.0024) and outside of the active ulcer (P = 0.0002) significantly decreased after scarring. Partitioning the cornea into different depths and annular zones, the anterior layer, center layer, and the 2-6 mm annular zone had a more remarkable COD decrease after scar formation. The 3rd-sorted COD in the anterior layer revealed the highest area under the receiver-operating characteristic curves (0.709), in which 90% of subjects had COD reduction during the ulcer-to-scar transition. CONCLUSIONS: Aside from subjective judgment based on clinical signs, the Scheimpflug tomography-based densitometry could provide objective and efficient monitoring of the corneal opacity evolution in UK patients. Because the 3rd-sorted annular COD is a better index than the inbuilt or mapping CODs in differentiating active ulcers from healed scars, this COD could be a clinically promising parameter to monitor the progression of UK patients.


Assuntos
Córnea , Úlcera da Córnea , Densitometria , Humanos , Estudos Prospectivos , Feminino , Masculino , Densitometria/métodos , Pessoa de Meia-Idade , Úlcera da Córnea/diagnóstico , Córnea/patologia , Córnea/diagnóstico por imagem , Seguimentos , Adulto , Cicatrização , Cicatriz/diagnóstico , Cicatriz/etiologia , Idoso , Curva ROC , Acuidade Visual , Topografia da Córnea/métodos , Opacidade da Córnea/diagnóstico , Opacidade da Córnea/etiologia , Opacidade da Córnea/fisiopatologia
9.
BMC Geriatr ; 24(1): 222, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38439017

RESUMO

BACKGROUND: This study aimed to investigate the association of high-sensitivity C-reactive protein (hs-CRP) with incident frailty as well as its effects on pre-frailty progression and regression among middle-aged and older adults. METHODS: Based on the frailty index (FI) calculated with 41 items, 6890 eligible participants without frailty at baseline from China Health and Retirement Longitudinal Study (CHARLS) were categorized into health, pre-frailty, and frailty groups. Logistic regression models were used to estimate the longitudinal association between baseline hs-CRP and incident frailty. Furthermore, a series of genetic approaches were conducted to confirm the causal relationship between CRP and frailty, including Linkage disequilibrium score regression (LDSC), pleiotropic analysis, and Mendelian randomization (MR). Finally, we evaluated the association of hs-CRP with pre-frailty progression and regression. RESULTS: The risk of developing frailty was 1.18 times (95% CI: 1.03-1.34) higher in participants with high levels of hs-CRP at baseline than low levels of hs-CRP participants during the 3-year follow-up. MR analysis suggested that genetically determined hs-CRP was potentially positively associated with the risk of frailty (OR: 1.06, 95% CI: 1.03-1.08). Among 5241 participants with pre-frailty at baseline, we found pre-frailty participants with high levels of hs-CRP exhibit increased odds of progression to frailty (OR: 1.39, 95% CI: 1.09-1.79) and decreased odds of regression to health (OR: 0.84, 95% CI: 0.72-0.98) when compared with participants with low levels of hs-CRP. CONCLUSIONS: Our results suggest that reducing systemic inflammation is significant for developing strategies for frailty prevention and pre-frailty reversion in the middle-aged and elderly population.


Assuntos
Proteína C-Reativa , Fragilidade , Idoso , Humanos , Pessoa de Meia-Idade , Estudos Longitudinais , Proteína C-Reativa/genética , Fragilidade/diagnóstico , Fragilidade/epidemiologia , Fragilidade/genética , Estudos de Coortes , Inflamação
10.
Aging Clin Exp Res ; 36(1): 140, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38965150

RESUMO

BACKGROUND: Sarcopenia has been reported to play an important role in frailty syndrome. The serum creatinine/serum cystatin C ratio (Scr/Cys C ratio) has recently been recognized as a valuable indicator for assessing sarcopenia. However, few studies have examined the association between serum creatinine/serum cystatin C ratio and frailty. The objective of this study is to investigate the relationship between the serum creatinine/serum cystatin C ratio and frailty among older adults residing in the community. METHODS AND MATERIALS: A Total of 1926 community-dwelling older adults aged ≥ 60 years in the 2011 waves of the China Health and Retirement Longitudinal Study (CHARLS) were included. The participants' frailty status was determined using a 39 item frailty index (FI), which classified individuals as "robust" (FI ≤ 0.1), "pre-frailty" (0.1 < FI < 0.25), or "frailty" (FI ≥ 0.25). The Scr/Cys C ratio was determined by dividing the serum creatinine level (mg/dL) by the cystatin C level (mg/L). The one-way analysis of variance(ANOVA) and Chi-squared test (χ2)were applied to compare the differences between the 3 groups. Both linear regression and logistic regression models were used to further investigate the relationship between Scr/Cys C ratio and frailty. RESULTS: After adjusting for potential confounding factors, the study revealed that participants in the Q1 quartile of Scr/Cys C ratio had increased odds of frailty (Q1vs.Q4: OR = 1.880, 95% CI 1.126-3.139, p = 0.016) compared with those in the Q4 quartile group. In fully adjusted logistic regression models, male participants in the Q2 quartile of Scr/Cys C ratio were significantly correlated with higher odds of pre-frailty (Q2 vs.Q4: OR = 1.693, 95%CI 1.040-2.758, p = 0.034). However, this correlation was not observed in females (OR = 0.984, 95% CI 0.589-1.642, p = 0.950,). Additionally, the study observed an increase in both the frailty index and the incidence of frailty as age increased in both males and females. CONCLUSION: Among community-dwelling older adults, lower Serum creatinine to cystatin C ratio were found to be associated with increased odds of frailty prevalence in males.


Assuntos
Creatinina , Cistatina C , Fragilidade , Vida Independente , Humanos , Cistatina C/sangue , Masculino , Idoso , Creatinina/sangue , Feminino , Fragilidade/sangue , Fragilidade/epidemiologia , Idoso de 80 Anos ou mais , Incidência , Pessoa de Meia-Idade , Idoso Fragilizado/estatística & dados numéricos , China/epidemiologia , Estudos Longitudinais , Sarcopenia/sangue , Sarcopenia/epidemiologia , Fatores Sexuais , Biomarcadores/sangue , Avaliação Geriátrica/métodos
11.
Nursing ; 54(3): 30-38, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38386448

RESUMO

ABSTRACT: Debridement is a core component of chronic wound management. Although various debridement methods exist, each carries a unique patient risk level. This article discusses the different normal tissue components that are critical to safe debridement practice, various methods of wound debridement for nurses, and the importance of an interprofessional team and consulting a wound specialist.


Assuntos
Desbridamento , Humanos
12.
Zhongguo Zhong Yao Za Zhi ; 49(13): 3627-3635, 2024 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-39041135

RESUMO

This study investigated the effects of ergosterol peroxide(EP) on the proliferation and apoptosis of MCF-7 breast cancer cells, explored its possible mechanisms of action, and verified the effects and mechanisms by in vitro experiments. Network pharmaco-logy was used to screen the target proteins of EP and construct target networks and protein-protein interaction(PPI) networks to predict the potential target proteins and related pathways involved in EP anti-breast cancer effects. The MTT assay was performed to measure the inhibitory effect of EP on MCF-7 cell proliferation, and the colony formation assay was used to assess the cell cloning ability. Flow cytometry and laser confocal microscopy were employed to evaluate cell apoptosis, mitochondrial membrane potential and reactive oxygen species(ROS) levels. Western blot analysis was conducted to examine the expression levels of B-cell lymphoma 2(Bcl-2), Bcl-2-associated X protein(Bax), cytochrome C(Cyt C), caspase-7, cleaved caspase-7, phosphatidylinositol 3-kinase(PI3K), and se-rine/threonine kinase B(AKT) in MCF-7 cells treated with EP. The results of network pharmacology prediction yielded 173 common targets between EP and breast cancer; the results of Kyoto Encyclopedia of Genes and Genomes(KEGG) enrichment analysis showed that EP treatment for breast cancer mainly affected the signaling pathways such as cancer pathway, PI3K-AKT signaling pathway, cellular senescence signaling pathway, and viral carcinogenesis pathway; and the MTT assay results showed that the viability of MCF-7 cells in the EP group was significantly lower than that in the control group, exhibiting a time-and concentration-dependent trend, and EP can inhibit colony formation of MCF-7 breast cancer cells. Treatment with 10, 20, and 40 µmol·L~(-1) EP for 24 h resulted in a significant increase in the total apoptosis rate of MCF-7 cells, a significant decrease in mitochondrial membrane potential, and a significant increase in ROS levels. In addition, treatment with EP led to an upregulation of Cyt C, Bax, and cleaved caspase-7 protein expression, and a downregulation of p-PI3K, p-AKT, and Bcl-2 protein expression in MCF-7 cells. Studies have shown that EP inhibits MCF-7 breast cancer cell proliferation and reduces colony formation by a mechanism that may be related to the PI3K-AKT pathway mediating the mitochondrial apoptotic pathway.


Assuntos
Apoptose , Neoplasias da Mama , Proliferação de Células , Ergosterol , Farmacologia em Rede , Humanos , Células MCF-7 , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Ergosterol/análogos & derivados , Ergosterol/farmacologia , Feminino , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Citocromos c/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/genética
13.
Huan Jing Ke Xue ; 45(1): 376-385, 2024 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-38216487

RESUMO

Per- and polyfluoroalkyl substances (PFAS) are a class of persistent organic pollutants that have attracted much attention in recent years, which has the characteristics of diverse species, refractory degradation, long-distance transportation, easy bioaccumulation, etc. The distribution, accumulation, and potential toxicity of PFAS in water and organisms have received extensive attention worldwide. However, studies on PFAS distribution and transportation in soil are still hovering at a preliminary stage. The PFAS pollution surveys in Chinese soils are mainly concentrated in the economically developed eastern regions. The types and concentrations of PFAS in soils are directly related to the industrial types, atmospheric deposition, and human activities in these surveyed areas, which are similar to foreign soil surveys. Traditional perfluoro carboxylic acid (PFCAs) and perfluoro octane sulfonate (PFSAs) are the most important types of PFAS in Chinese soils. This study reviewed the distribution characteristics, transportation pathways, and influencing factors of PFAS in Chinese soils, as well as domestic and foreign control policies on PFAS pollution. Meanwhile, this study further pointed out the shortcomings of the current research on the distribution and control of PFAS in soil in order to provide a reference for the investigation, research, and control of PFAS pollution in Chinese soils.

14.
ACS Omega ; 9(22): 24095-24104, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38854553

RESUMO

Herein, we propose a Carbopol hydrogel-based oxygen nanodelivery "nanohyperbaric" system as a wound dressing material for an enhanced wound healing process. Oxygen nanobubbles (ONBs) were used to supply oxygen, and collagenase was added in the gel as a drug model. Both oxygen and collagenase would benefit the wound healing process, and the Carbopol hydrogel serves as the matrix to load ONBs and collagenase in the wound dressing. The obtained ONB-embedded Carbopol hydrogel with collagenase (ONB-CC) could provide 12.08 ± 0.75 µg of oxygen from 1 mL of ONB-CC and exhibited a notable capacity to prolong the oxygen holding for up to 3 weeks and maintained the enzymatic activity of collagenase at more than 0.05 U per 0.1 mL of ONB-CC for up to 17 days. With HDFa cells, the ONB-CC did not show a notable effect on the cell viability. In a scratch assay, the oxygen from ONBs or collagenase aided cell migration; further, the ONB-CC induced the most obvious scratch closure, indicating an improvement in wound healing as a cocktail in the ONB-CC. The mRNA expression further demonstrated the effectiveness of the ONB-CC. Studies in rats with punched wounds treated with the ONB-CC dressing showed improved wound closure. Histopathological images showed that the ONB-CC dressing enhanced re-epithelization and formation of new blood vessels and hair follicles. The proposed ONB-CC has excellent potential as an ideal wound dressing material to accelerate wound healing by integration of multiple functions.

15.
J Colloid Interface Sci ; 673: 104-112, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38875782

RESUMO

Flexible electrodes based on conversion-type materials have potential applications in low-cost and high-performance flexible sodium-ion batteries (FSIBs), owing to their high theoretical capacity and appropriate sodiation potential. However, they suffer from flexible electrodes with poor mechanical properties and sluggish reaction kinetics. In this study, freestanding CoS2 nanoparticles coupled with graphene oxides and carbon nanotubes (CoS2/GO/CNTs) flexible films with robust and interconnected architectures were successfully synthesized. CoS2/GO/CNTs flexible film displays high electronic conductivity and superior mechanical properties (average tensile strength of 21.27 MPa and average toughness of 393.18 KJ m-3) owing to the defect bridge for electron transfer and the formation of the π-π interactions between CNTs and GO. In addition, the close contact between the CoS2 nanoparticles and carbon networks enabled by the Co-N chemical bond prevents the self-aggregation of the CoS2 nanoparticles. As a result, the CoS2/GO/CNTs flexible film delivered superior rate capability (213.5 mAh g-1 at 6 A g-1, better than most reported flexible anode) and long-term cycling stability. Moreover, the conversion reaction that occurred in the CoS2/GO/CNTs flexible film exhibited pseudocapacitive behavior. This study provides meaningful insights into the development of flexible electrodes with superior mechanical properties and electrochemical performance for energy storage.

16.
Sci Total Environ ; 915: 169949, 2024 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-38220004

RESUMO

Spatial arrangement is a key factor in maintaining community yield and stability via regulating component intra-/interspecific competition in an alpine climate environment. A 2-yr field trial was conducted on the Qinghai Tibetan Plateau, including cross row (S_C), double row (S_D), single row (S_R), broadcast (M_B), dependent row (M_D) and independent row (M_I). Our results showed that S_C could avoid intraspecific competition by reasonable spatial arrangement, which favored the dominant component growth (1st year: leaf; 2nd year: stem and reproductive organ). For mixed communities, RII (relative interaction intensity) implied that interspecific competition also embodied on dominant component, and higher Elymus nutans component advantages seriously limited Onobrychis viciifolia's components growth in the 2nd year. More details displayed that E. nutans in M_B or M_D produced the maximum system yield via increasing leaf investment at the initial stages and stem investment after July 2019. Besides, M_I possessed lower component numbers than M_B and M_D in the unit area. PCA analysis revealed that component numbers or biomasses changed synchronously, besides the E. nutans of S_C, M_B, and M_D presented significant discrepancies compared to other treatments in September 2019, which verified the effect of sowing patterns on component growth (P < 0.05), but O. viciifolia in different sowing patterns was similar in the 2nd year. Considering the adaptability and production for the environment of the Qinghai Tibetan Plateau, S_C is recommended for the promoted effect on component biomasses. M_B and M_D, with the merit of spacing utilization as well as higher resistance to variation in seasonal growth conditions via optimizing interspecific relationships for mixed communities, are adapted for increasing yield via component harvesting. Our results unveiled the potential of optimizing spatial usage efficiency via controlling component growth characteristics and stressed the importance of dynamic change of dominant components to enhance forage system production in alpine regions.


Assuntos
Elymus , Tibet , Pradaria , Clima , Biomassa
17.
Bioact Mater ; 35: 67-81, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38312517

RESUMO

Hypoxia, excessive reactive oxygen species (ROS), and impaired angiogenesis are prominent obstacles to wound healing following trauma and surgical procedures, often leading to the development of keloids and hypertrophic scars. To address these challenges, a novel approach has been proposed, involving the development of a cascade enzymatic reaction-based nanocarriers-laden wound dressing. This advanced technology incorporates superoxide dismutase modified oxygen nanobubbles and catalase modified oxygen nanobubbles within an alginate hydrogel matrix. The oxygen nano chamber functions through a cascade reaction between superoxide dismutase and catalase, wherein excessive superoxide in the wound environment is enzymatically decomposed into hydrogen peroxide, and this hydrogen peroxide is subsequently converted into oxygen by catalase. This enzymatic cascade effectively controls wound inflammation and hypoxia, mitigating the risk of keloid formation. Concurrently, the oxygen nanobubbles release oxygen continuously, thus providing a sustained supply of oxygen to the wound site. The oxygen release from this dynamic system stimulates fibroblast proliferation, fosters the formation of new blood vessels, and contributes to the overall wound healing process. In the rat full-thickness wound model, the cascade reaction-based nano oxygen chamber displayed a notable capacity to expedite wound healing without scarring. Furthermore, in the pilot study of porcine full-thickness wound healing, a notable acceleration of tissue repair was observed in the conceived cascade reaction-based gel treated group within the 3 days post-surgery, which represents the proliferation stage of healing process. These achievements hold significant importance in ensuring the complete functional recovery of tissues, thereby highlighting its potential as a promising approach for enhancing wound healing outcomes.

18.
Technol Health Care ; 32(3): 1657-1666, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38108366

RESUMO

BACKGROUND: Acute pancreatitis (AP) is a severe condition with complications that can impact multiple organ systems throughout the body. Specifically, the diffusion of peripancreatic effusion to the pleural cavity is a significant phenomenon in AP. However, its pathways and implications for disease severity are not fully understood. OBJECTIVE: This study aims to investigate the anatomical routes of peripancreatic effusion diffusion into the pleural cavity in patients with AP and to analyze the correlation between the severity of pleural effusion (PE) and the computed tomography severity index (CTSI) and acute physiology and chronic health evaluation II (APACHE II) scoring system. METHODS: 119 patients with AP admitted to our institution were enrolled in this study (mean age 50 years, 74 male and 45 female). Abdominal CT was performed, and the CTSI and APACHE II index were used to evaluate the severity of the AP, Meanwhile, the prevalence and semiquantitative of PE were also mentioned. The anatomical pathways of peripancreatic effusion draining to pleural were analyzed. Finally, the correlation relationship between the severity of AP and the PE was analyzed. RESULTS: In 119 patients with AP, 74.8% of patients had PE on CT. The anatomic pathways of peripancreatic effusion draining to pleural included esophageal hiatus in 33.7% of patients, aortic hiatus in 6.7% of patients and inferior vena cava hiatus in 3.37% of patients. The rating of PE on CT was correlated with CTSI scores (r= 0.449, P= 0.000) and was slightly correlated with the APACHE II scores (r= 0.197, P= 0.016). CONCLUSION: PE is a common complication of AP, which can be caused by anatomic pathways such as diaphragmatic hiatus. Due to its correlation with the CTSI score, the PE may be a supplementary indicator in determining the severity of AP.


Assuntos
Pancreatite , Derrame Pleural , Índice de Gravidade de Doença , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Derrame Pleural/diagnóstico por imagem , Derrame Pleural/epidemiologia , Pancreatite/diagnóstico por imagem , Pancreatite/complicações , Adulto , Idoso , APACHE , Tomografia Computadorizada por Raios X/métodos , Doença Aguda , Tomografia Computadorizada Multidetectores/métodos
19.
Int J Biol Macromol ; 273(Pt 1): 132993, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38862049

RESUMO

Low ionic conductivity and poor interface stability of poly(ethylene oxide) (PEO) restrict the practical application as polymeric electrolyte films to prepare solid-state lithium (Li) metal batteries. In this work, biomass-based carboxymethyl chitosan (CMCS) is designed and developed as organic fillers into PEO matrix to form composite electrolytes (PEO@CMCS). Carboxymethyl groups of CMCS fillers can promote the decomposition of Lithium bis(trifluoromethane sulfonimide) (LiTFSI) to generate more lithium fluoride (LiF) at CMCS/PEO interface, which not only forms ionic conductive network to promote the rapid transfer of Li+ but also effectively enhances the interface stability between polymeric electrolyte and Li metal. The enrichment of carboxyl, hydroxyl, and amidogen functional groups within CMCS fillers can form hydrogen bonds with ethylene oxide (EO) chains to improve the tensile properties of PEO-based electrolyte. In addition, the high hardness of CMCS additives can also strengthen mechanical properties of PEO-based electrolyte to resist penetration of Li dendrites. LiLi symmetric batteries can achieve stable cycle for 2500 h and lithium iron phosphate full batteries can maintain 135.5 mAh g-1 after 400 cycles. This work provides a strategy for the enhancement of ion conductivity and interface stability of PEO-based electrolyte, as well as realizes the resource utilization of biomass-based CMCS.


Assuntos
Quitosana , Condutividade Elétrica , Fontes de Energia Elétrica , Eletrólitos , Lítio , Polietilenoglicóis , Quitosana/química , Quitosana/análogos & derivados , Polietilenoglicóis/química , Lítio/química , Eletrólitos/química , Íons/química
20.
Nat Commun ; 15(1): 3435, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38653959

RESUMO

Wound healing is an obvious clinical concern that can be hindered by inadequate angiogenesis, inflammation, and chronic hypoxia. While exosomes derived from adipose tissue-derived stem cells have shown promise in accelerating healing by carrying therapeutic growth factors and microRNAs, intracellular cargo delivery is compromised in hypoxic tissues due to activated hypoxia-induced endocytic recycling. To address this challenge, we have developed a strategy to coat oxygen nanobubbles with exosomes and incorporate them into a polyvinyl alcohol/gelatin hybrid hydrogel. This approach not only alleviates wound hypoxia but also offers an efficient means of delivering exosome-coated nanoparticles in hypoxic conditions. The self-healing properties of the hydrogel, along with its component, gelatin, aids in hemostasis, while its crosslinking bonds facilitate hydrogen peroxide decomposition, to ameliorate wound inflammation. Here, we show the potential of this multifunctional hydrogel for enhanced healing, promoting angiogenesis, facilitating exosome delivery, mitigating hypoxia, and inhibiting inflammation in a male rat full-thickness wound model.


Assuntos
Exoma , Nanopartículas , Oxigênio , Cicatrização , Nanopartículas/administração & dosagem , Cicatrização/efeitos dos fármacos , Hipóxia , Oxigênio/administração & dosagem , Oxigênio/farmacologia , Hidrogéis , Neovascularização Fisiológica/efeitos dos fármacos , Humanos , Células Cultivadas , Células-Tronco Mesenquimais/efeitos dos fármacos , Sistemas de Liberação de Medicamentos , Masculino , Animais , Ratos
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