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1.
Neural Regen Res ; 20(3): 695-714, 2025 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38886936

RESUMO

Alzheimer's disease, the primary cause of dementia, is characterized by neuropathologies, such as amyloid plaques, synaptic and neuronal degeneration, and neurofibrillary tangles. Although amyloid plaques are the primary characteristic of Alzheimer's disease in the central nervous system and peripheral organs, targeting amyloid-beta clearance in the central nervous system has shown limited clinical efficacy in Alzheimer's disease treatment. Metabolic abnormalities are commonly observed in patients with Alzheimer's disease. The liver is the primary peripheral organ involved in amyloid-beta metabolism, playing a crucial role in the pathophysiology of Alzheimer's disease. Notably, impaired cholesterol metabolism in the liver may exacerbate the development of Alzheimer's disease. In this review, we explore the underlying causes of Alzheimer's disease and elucidate the role of the liver in amyloid-beta clearance and cholesterol metabolism. Furthermore, we propose that restoring normal cholesterol metabolism in the liver could represent a promising therapeutic strategy for addressing Alzheimer's disease.

2.
JMIR Public Health Surveill ; 10: e52536, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39092523

RESUMO

Background: Hypertension is the most prevalent chronic disease among China's older population, which comprises a growing proportion of the overall demographic. Older individuals with chronic diseases have a higher risk of developing depressive symptoms than their healthy counterparts, as evidenced in China's older population, where patients with hypertension exhibit varying rates of depression depending on residing in urban or rural areas. Objective: This study aimed to investigate factors influencing and contributing to the disparities in depressive symptoms among older urban and rural patients with hypertension in China. Methods: We used a cross-sectional study design and derived data from the 8th Chinese Longitudinal Health Longevity Survey of 2018. The Fairlie model was applied to analyze the factors contributing to disparities in depressive symptoms between urban and rural older populations with hypertension. Results: The sample size for this study was 5210, and 12.8% (n=669) of participants exhibited depressive symptoms. The proportions of depressive symptoms in rural and urban areas were 14.1% (n=468) and 10.7% (n=201), respectively. In rural areas, years of education (1-6 years: odds ratio [OR] 0.68, 95% CI 1.10-1.21; ≥7 years: OR 0.47, 95% CI 0.24-0.94), alcohol consumption (yes: OR 0.52, 95% CI 0.29-0.93), exercise (yes: OR 0.78, 95% CI 0.56-1.08), and sleep duration (6.0-7.9 hours: OR 0.29, 95% CI 0.17-0.52; 8.0-9.9 hours: OR 0.24, 95% CI 0.13-0.43; ≥10.0 hours: OR 0.22, 95% CI 0.11-0.41) were protective factors against depressive symptoms in older adults with hypertension, while gender (female: OR 1.94, 95% CI 1.33-2.81), self-reported income status (poor: OR 3.07, 95% CI 2.16-4.37), and activities of daily living (ADL) dysfunction (mild: OR 1.69, 95% CI 1.11-2.58; severe: OR 3.03, 95% CI 1.46-6.32) were risk factors. In urban areas, age (90-99 years: OR 0.37, 95% CI 0.16-0.81; ≥100 years: OR 0.19, 95% CI 0.06-0.66), exercise (yes: OR 0.33, 95% CI 0.22-0.51), and sleep duration (6.0-7.9 hours: OR 0.27, 95% CI 0.10-0.71; 8.0-9.9 hours: OR 0.16, 95% CI 0.06-0.44; ≥10.0 hours: OR 0.18, 95% CI 0.06-0.57) were protective factors, while years of education (1-6 years: OR 1.91, 95% CI 1.05-3.49), self-reported income status (poor: OR 2.94, 95% CI 1.43-6.08), and ADL dysfunction (mild: OR 2.38, 95% CI 1.39-4.06; severe: OR 3.26, 95% CI 1.21-8.76) were risk factors. The Fairlie model revealed that 91.61% of differences in depressive symptoms could be explained by covariates, including years of education (contribution 63.1%), self-reported income status (contribution 13.2%), exercise (contribution 45.7%), sleep duration (contribution 20.8%), ADL dysfunction (contribution -9.6%), and comorbidities (contribution -22.9%). Conclusions: Older patients with hypertension in rural areas had more depressive symptoms than their counterparts residing in urban areas, which could be explained by years of education, self-reported income status, exercise, sleep duration, ADL dysfunction, and comorbidities. Factors influencing depressive symptoms had similarities regarding exercise, sleep duration, self-reported income status, and ADL dysfunction as well as differences regarding age, gender, years of education, and alcohol consumption.


Assuntos
Depressão , Hipertensão , População Rural , População Urbana , Humanos , Estudos Transversais , Masculino , Feminino , Hipertensão/epidemiologia , Hipertensão/psicologia , Idoso , China/epidemiologia , População Rural/estatística & dados numéricos , População Urbana/estatística & dados numéricos , Depressão/epidemiologia , Depressão/psicologia , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Fatores de Risco
3.
Cell Mol Life Sci ; 81(1): 340, 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39120696

RESUMO

Copper is a trace element essential for numerous biological activities, whereas the mitochondria serve as both major sites of intracellular copper utilization and copper reservoir. Here, we investigated the impact of mitochondrial copper overload on the tricarboxylic acid cycle, renal senescence and fibrosis. We found that copper ion levels are significantly elevated in the mitochondria in fibrotic kidney tissues, which are accompanied by reduced pyruvate dehydrogenase (PDH) activity, mitochondrial dysfunction, cellular senescence and renal fibrosis. Conversely, lowering mitochondrial copper levels effectively restore PDH enzyme activity, improve mitochondrial function, mitigate cellular senescence and renal fibrosis. Mechanically, we found that mitochondrial copper could bind directly to lipoylated dihydrolipoamide acetyltransferase (DLAT), the E2 component of the PDH complex, thereby changing the interaction between the subunits of lipoylated DLAT, inducing lipoylated DLAT protein dimerization, and ultimately inhibiting PDH enzyme activity. Collectively, our study indicates that mitochondrial copper overload could inhibit PDH activity, subsequently leading to mitochondrial dysfunction, cellular senescence and renal fibrosis. Reducing mitochondrial copper overload might therefore serve as a strategy to rescue renal fibrosis.


Assuntos
Senescência Celular , Cobre , Fibrose , Rim , Mitocôndrias , Complexo Piruvato Desidrogenase , Cobre/metabolismo , Mitocôndrias/metabolismo , Fibrose/metabolismo , Animais , Complexo Piruvato Desidrogenase/metabolismo , Rim/metabolismo , Rim/patologia , Di-Hidrolipoil-Lisina-Resíduo Acetiltransferase/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Humanos , Nefropatias/metabolismo , Nefropatias/patologia , Ciclo do Ácido Cítrico
4.
ACS Appl Mater Interfaces ; 16(32): 42221-42229, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39088744

RESUMO

Quasi-two-dimensional (quasi-2D) layered perovskites with mixed dimensions offer a promising avenue for stable and efficient solar cells. However, randomly distributed three-dimensional (3D) perovskites near the film surface limit the device performance of quasi-2D perovskites due to increased nonradiative recombination and ion migration. Herein, we construct a 2D (n = 4 top)-3D-2D (n = 2 bottom) heterostructure of quasi-2D perovskites by using 3-chlorobenzylamine iodine, which can effectively reduce defect density and restrain ion migration. A champion efficiency of 22.22% for quasi-2D perovskite solar cells is achieved due to remarkably reduced nonradiative voltage loss and increased electron extraction. Additionally, the 2D-3D-2D perovskite solar cells also exhibit excellent thermal and humidity stabilities, retaining over 90 and 85% of the initial efficiencies after 2000 h under a heat stress of 65 °C and at air ambient of ∼50% humidity, respectively. Our results provide a general approach to tune perovskite films for suppressing ion migration and achieving high-performance perovskite solar cells.

5.
Regen Biomater ; 11: rbae078, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39055303

RESUMO

The intricate nature of oral-maxillofacial structure and function, coupled with the dynamic oral bacterial environment, presents formidable obstacles in addressing the repair and regeneration of oral-maxillofacial bone defects. Numerous characteristics should be noticed in oral-maxillofacial bone repair, such as irregular morphology of bone defects, homeostasis between hosts and microorganisms in the oral cavity and complex periodontal structures that facilitate epithelial ingrowth. Therefore, oral-maxillofacial bone repair necessitates restoration materials that adhere to stringent and specific demands. This review starts with exploring these particular requirements by introducing the particular characteristics of oral-maxillofacial bones and then summarizes the classifications of current bone repair materials in respect of composition and structure. Additionally, we discuss the modifications in current bone repair materials including improving mechanical properties, optimizing surface topography and pore structure and adding bioactive components such as elements, compounds, cells and their derivatives. Ultimately, we organize a range of potential optimization strategies and future perspectives for enhancing oral-maxillofacial bone repair materials, including physical environment manipulation, oral microbial homeostasis modulation, osteo-immune regulation, smart stimuli-responsive strategies and multifaceted approach for poly-pathic treatment, in the hope of providing some insights for researchers in this field. In summary, this review analyzes the complex demands of oral-maxillofacial bone repair, especially for periodontal and alveolar bone, concludes multifaceted strategies for corresponding biomaterials and aims to inspire future research in the pursuit of more effective treatment outcomes.

6.
J Biol Chem ; 300(8): 107512, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38960037

RESUMO

The Hippo-YAP signaling pathway plays a central role in many biological processes such as regulating cell fate, organ size, and tissue growth, and its key components are spatiotemporally expressed and posttranslationally modified during these processes. Neddylation is a posttranslational modification that involves the covalent attachment of NEDD8 to target proteins by NEDD8-specific E1-E2-E3 enzymes. Whether neddylation is involved in Hippo-YAP signaling remains poorly understood. Here, we provide evidence supporting the critical role of NEDD8 in facilitating the Hippo-YAP signaling pathway by mediating neddylation of the transcriptional coactivator yes-associated protein 1 (YAP1). Overexpression of NEDD8 induces YAP1 neddylation and enhances YAP1 transactivity, but inhibition of neddylation suppresses YAP1 transactivity and attenuates YAP1 nuclear accumulation. Furthermore, inhibition of YAP1 signaling promotes MLN4924-induced ovarian granulosa cells apoptosis and disruption of nedd8 in zebrafish results in downregulation of yap1-activated genes and upregulation of yap1-repressed genes. Further assays show that the xiap ligase promotes nedd8 conjugates to yap1 and that yap1 neddylation. In addition, we identify lysine 159 as a major neddylation site on YAP1. These findings reveal a novel mechanism for neddylation in the regulation of Hippo-YAP signaling.

7.
Neural Regen Res ; 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38993129

RESUMO

ABSTRACT: The M1/M2 phenotypic shift of microglia after spinal cord injury plays an important role in the regulation of neuroinflammation during the secondary injury phase of spinal cord injury. Regulation of shifting microglia polarization from M1 (neurotoxic and proinflammatory type) to M2 (neuroprotective and anti-inflammatory type) after spinal cord injury appears to be crucial. Tryptanthrin possesses an anti-inflammatory biological function. However, its roles and the underlying molecular mechanisms in spinal cord injury remain unknown. In this study, we found that tryptanthrin inhibited microglia-derived inflammation by promoting polarization to the M2 phenotype in vitro. Tryptanthrin promoted M2 polarization through inactivating the cGAS/STING/NF-κB pathway. Additionally, we found that targeting the cGAS/STING/NF-κB pathway with tryptanthrin shifted microglia from the M1 to M2 phenotype after spinal cord injury, inhibited neuronal loss, and promoted tissue repair and functional recovery in a mouse model of spinal cord injury. Finally, using a conditional co-culture system, we found that microglia treated with tryptanthrin suppressed endoplasmic reticulum stress-related neuronal apoptosis. Taken together, these results suggest that by targeting the cGAS/STING/NF-κB axis, tryptanthrin attenuates microglia-derived neuroinflammation and promotes functional recovery after spinal cord injury through shifting microglia polarization to the M2 phenotype.

8.
Vet Res ; 55(1): 85, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38970094

RESUMO

Phage therapy holds promise as an alternative to antibiotics for combating multidrug-resistant bacteria. However, host bacteria can quickly produce progeny that are resistant to phage infection. In this study, we investigated the mechanisms of bacterial resistance to phage infection. We found that Rsm1, a mutant strain of Salmonella enteritidis (S. enteritidis) sm140, exhibited resistance to phage Psm140, which was originally capable of lysing its host at sm140. Whole genome sequencing analysis revealed a single nucleotide mutation at position 520 (C → T) in the rfbD gene of Rsm1, resulting in broken lipopolysaccharides (LPS), which is caused by the replacement of CAG coding glutamine with a stop codon TAG. The knockout of rfbD in the sm140ΔrfbD strain caused a subsequent loss of sensitivity toward phages. Furthermore, the reintroduction of rfbD in Rsm1 restored phage sensitivity. Moreover, polymerase chain reaction (PCR) amplification of rfbD in 25 resistant strains revealed a high percentage mutation rate of 64% within the rfbD locus. We assessed the fitness of four bacteria strains and found that the acquisition of phage resistance resulted in slower bacterial growth, faster sedimentation velocity, and increased environmental sensitivity (pH, temperature, and antibiotic sensitivity). In short, bacteria mutants lose some of their abilities while gaining resistance to phage infection, which may be a general survival strategy of bacteria against phages. This study is the first to report phage resistance caused by rfbD mutation, providing a new perspective for the research on phage therapy and drug-resistant mechanisms.


Assuntos
Mutação Puntual , Fagos de Salmonella , Salmonella enteritidis , Salmonella enteritidis/virologia , Salmonella enteritidis/fisiologia , Salmonella enteritidis/genética , Fagos de Salmonella/fisiologia , Fagos de Salmonella/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo
9.
BMC Ophthalmol ; 24(1): 298, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39030533

RESUMO

BACKGROUND: To establish a normative database for macular vessel density (VD) measured by optical coherence tomography angiography (OCTA) and explore the parameters related to the VD. METHODS: An observational study in epidemiology. 5840 healthy elderly participants in Beichen district, Tianjin, China underwent detailed ophthalmic and systemic examinations. OCTA was performed in all subjects using a 6 × 6-mm line scan mode centered on the macula and the built-in software was used to quantify VD and stratify the retina. RESULTS: One thousand four hundred sixty-one healthy elderly citizens (30.4% men) were included, with a median age of 60.0 years (8.0 years) and an age range of 50 to 87 years.VDs in the different plexuses: superficial capillary plexus (SCP) 43.9% (3.2%), deep capillary plexus (DCP) 44.3% (2.8%), outer capillary plexus (OCP) 21.9% (5.9%), choriocapillaris (CC) 52.1% (1.4%). 90% medical reference range of the VDs at different plexuses was reported. Age was correlated with the VDs of each capillary plexus. Sex was correlated with the VDs of DCP and OCP, and the VDs of DCP (p < 0.001) and OCP (p = 0.015) in women were higher than that in men. After age and sex adjustment, choroid average thickness was positively correlated with VDs of SCP (R = 0.067, p = 0.010) and DCP (R = 0.108, p < 0.001), ganglion cell layer (GCL) average thickness (R = 0.072, p = 0.006) was positively correlated with the VD of OCP, best-corrected visual acuity (BCVA) (R = 0.082, p = 0.002) was positively correlated with the VD of CC. CONCLUSIONS: In this study, the normative VD database of the Chinese urban healthy elderly population measured by the OCTA was established, and parameters related to the VD of each capillary plexus were analyzed, providing new ideas for the future study of the relationship between macular VD and disease. TRIAL REGISTRATION: The Beichen Eye Study had been registered on the Chinese Clinical Trial Registry website (registry number: ChiCTR2000032280) on April 25, 2020.


Assuntos
Angiofluoresceinografia , Vasos Retinianos , Tomografia de Coerência Óptica , Humanos , Tomografia de Coerência Óptica/métodos , Idoso , Masculino , Feminino , Vasos Retinianos/diagnóstico por imagem , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , China/epidemiologia , Angiofluoresceinografia/métodos , Valores de Referência , População Urbana , Macula Lutea/diagnóstico por imagem , Macula Lutea/irrigação sanguínea , Voluntários Saudáveis , Fundo de Olho , Densidade Microvascular , População do Leste Asiático
10.
Front Vet Sci ; 11: 1395188, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39011320

RESUMO

Aims: Clostridium perfringens is one of the major anaerobic pathogen causing food poisoning and animal enteritis. With the rise of antibiotic resistance and the restrictions of the use of antibiotic growth promoting agents (AGPs) in farming, Clostridium enteritis and food contamination have become more common. It is time-consuming and labor-intensive to confirm the detection by standard culture methods, and it is necessary to develop on-site rapid detection tools. In this study, a combination of recombinase polymerase amplification (RPA) and lateral flow biosensor (LFB) was used to visually detect C. perfringens in chicken meat and milk. Methods and results: Two sets of primers were designed for the plc gene of C. perfringens, and the amplification efficiency and specificity of the primers. Selection of primers produces an amplified fragment on which the probe is designed. The probe was combined with the lateral flow biosensor (LFB). The reaction time and temperature of RPA-LFB assay were optimized, and the sensitivity of the assay was assessed. Several common foodborne pathogens were selected to test the specificity of the established method. Chicken and milk samples were artificially inoculated with different concentrations (1 × 102 CFU/mL to 1 × 106 CFU/mL) of C. perfringens, and the detection efficiency of RPA-LFB method and PCR method was compared. RPA-LFB can be completed in 20 min and the results can be read visually by the LFB test strips. The RPA-LFB has acceptable specificity and the lowest detection limit of 100 pg./µL for nucleic acid samples. It was able to stably detect C. perfringens contamination in chicken and milk at the lowest concentration of 1 × 104 CFU/mL and 1 × 103 CFU/mL, respectively. Conclusion: In conclusion, RPA-LFB is specific and sensitive. It is a rapid, simple and easy-to-visualize method for the detection of C. perfringens in food and is suitable for use in field testing work.

11.
iScience ; 27(7): 110210, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39055914

RESUMO

Pseudomonas aeruginosa is a common opportunistic pathogen. The potential efficacy of phage therapy has attracted the attention of researchers, but efficient gene-editing tools are lacking, limiting the study of their biological properties. Here, we designed a type V CRISPR-Cas12a system for the gene editing of P. aeruginosa phages. We first evaluated the active cutting function of the CRISPR-Cas12a system in vitro and discovered that it had a higher gene-cutting efficiency than the type II CRISPR-Cas9 system in three different P. aeruginosa phages. We also demonstrated the system's ability to precisely edit genes in Escherichia coli phages, Salmonella phages, and P. aeruginosa phages. Using the aforementioned strategies, non-essential P. aeruginosa phage genes can be efficiently deleted, resulting in a reduction of up to 5,215 bp (7.05%). Our study has provided a rapid, efficient, and time-saving tool that accelerates progress in phage engineering.

12.
Cancer Lett ; 598: 217115, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39025428

RESUMO

Gut microbiota contributes to the homeostasis of immune system and is related to various diseases such as tumorigenesis. Ferroptosis, a new type of cell death, is also involved in the disease pathogenesis. Recent studies have found the correlations of gut microbiota mediated ferroptosis and immune cell death. Gut microbiota derived immunosuppressive metabolites, which can promote differentiation and function of immune cells, tend to inhibit ferroptosis through their receptors, whereas inflammatory metabolites from gut microbiota also affect the differentiation and function of immune cells and their ferroptosis. Thus, it is possible for gut microbiota to regulate immune cell ferroptosis. Indeed, gut microbiota metabolite receptor aryl hydrocarbon receptor (AhR) can affect ferroptosis of intestinal intraepithelial lymphocytes, leading to disease pathogenesis. Since immune cell ferroptosis in tumor microenvironment (TME) affects the occurrence and development of tumor, the modulation of gut microbiota in these cell ferroptosis might influence on the tumorigenesis, and also immunotherapy against tumors. Here we will summarize the recent advance of ferroptosis mediated by gut microbiota metabolites, which potentially acts as regulator(s) on immune cells in TME for therapy against tumor.

14.
Food Chem ; 455: 139873, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-38850987

RESUMO

The kind of compounding emulsifier used and the amount of compounding have a significant impact on the emulsion's stability. In this study, the average particle size, Zeta potential, emulsification index, laser confocal microstructure, and rheological properties shows that the ratio of monoglyceride-xanthan gum and sucrose ester-xanthan gum could maintain the good stability of the emulsion in a certain range, and the monoglyceride and sucrose ester compounding could effectively improve the stability of the emulsion in a specific ratio (7:3). The results of fluorescence spectroscopy, Fourier transform infrared spectroscopy and sodium dodecyl sulfate polyacrylamide gel electrophoresis indicated that the simultaneous complexation of three substances was more likely to produce hydrophobic interactions with walnut proteins than the simultaneous complexation of two substances. Also confirmed were the hydrogen bonding connections between the proteins and the monoglyceride, sucrose ester, and xanthan gum. Monoglyceride and xanthan gum complexes were also found to stabilize more proteins.


Assuntos
Emulsificantes , Emulsões , Juglans , Polissacarídeos Bacterianos , Polissacarídeos Bacterianos/química , Emulsificantes/química , Juglans/química , Emulsões/química , Tamanho da Partícula , Leite/química , Reologia , Interações Hidrofóbicas e Hidrofílicas , Animais
15.
PeerJ ; 12: e17341, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38827281

RESUMO

Phosphorus is one of the lowest elements absorbed and utilized by plants in the soil. SPX domain-containing genes family play an important role in plant response to phosphate deficiency signaling pathway, and related to seed development, disease resistance, absorption and transport of other nutrients. However, there are no reports on the mechanism of SPX domain-containing genes in response to phosphorus deficiency in eggplant. In this study, the whole genome identification and functional analysis of SPX domain-containing genes family in eggplant were carried out. Sixteen eggplant SPX domain-containing genes were identified and divided into four categories. Subcellular localization showed that these proteins were located in different cell compartments, including nucleus and membrane system. The expression patterns of these genes in different tissues as well as under phosphate deficiency with auxin were explored. The results showed that SmSPX1, SmSPX5 and SmSPX12 were highest expressed in roots. SmSPX1, SmSPX4, SmSPX5 and SmSPX14 were significantly induced by phosphate deficiency and may be the key candidate genes in response to phosphate starvation in eggplant. Among them, SmSPX1 and SmSPX5 can be induced by auxin under phosphate deficiency. In conclusion, our study preliminary identified the SPX domain genes in eggplant, and the relationship between SPX domain-containing genes and auxin was first analyzed in response to phosphate deficiency, which will provide theoretical basis for improving the absorption of phosphorus in eggplants through molecular breeding technology.


Assuntos
Regulação da Expressão Gênica de Plantas , Proteínas de Plantas , Solanum melongena , Solanum melongena/genética , Solanum melongena/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Ácidos Indolacéticos/metabolismo , Genoma de Planta/genética , Família Multigênica , Fósforo/metabolismo , Fósforo/deficiência , Genes de Plantas , Fosfatos/metabolismo , Fosfatos/deficiência
16.
Carbohydr Polym ; 340: 122234, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-38858015

RESUMO

Porous starch materials are promising in several applications as renewable natural biomaterials. This study reports an approach combining methacrylation of starch and chemical crosslinked cryogelation to fabricate highly elastic macroporous starch (ST-MA) cryogels with impressed water/oil absorption capacity and wet thermal stability among starch based porous materials. Five different types of starch, including pea, normal corn, high amylose corn, tapioca, and waxy maize starch with different amylose content, have been studied. The methacrylation degree is not related with amylose content. All cryogels exhibited excellent compressive elasticity enduring 90 % deformation without failure and good robustness in cyclic tests. The ST-MA cryogels from pea starch exhibited the highest Young's modulus and compressive strength among five types of starch. These covalent cryogels exhibit high wet-thermal stability and enzymatic hydrolysis stability, while still are biodegradable. The dry ST-MA sponges (2 wt%) showed outstanding liquid absorption capacity, absorbing ~40 folds (g/g) of water or ~ 36 folds (g/g) of oil respectively. All types of starch have similar liquid absorption performance. This study provides a universal approach to fabricate highly elastic covalent starch macroporous materials with impressed liquid absorption capacity and outstanding stability, especially wet-thermal stability, and may expand their applications.

18.
Sheng Li Xue Bao ; 76(3): 487-495, 2024 Jun 25.
Artigo em Chinês | MEDLINE | ID: mdl-38939942

RESUMO

Copper is a vital trace metal element necessary for the functioning of living organisms. It serves as a co-factor or structural component in numerous enzymes, participating in crucial biological metabolic processes. Disruptions in copper homeostasis, whether inherited or acquired, such as copper overload, deficiency, or uneven distribution, can contribute to or exacerbate various diseases, including Menkes disease, Wilson's disease, neurodegenerative disorders, anemia, cardiovascular diseases, kidney diseases and cancer. Recent research has highlighted the close correlation between chronic kidney disease and intracellular copper overload. Therefore, renal cells must establish a well-organized and efficient copper regulation network to maintain intracellular copper homeostasis. This review summarizes the processes of copper uptake, intracellular trafficking, storage, and excretion in renal cells, and elucidates the underlying mechanisms involved, aiming to provide a theoretical foundation and potential therapeutic targets for the fundamental investigation and clinical management of kidney-related diseases.


Assuntos
Cobre , Homeostase , Rim , Homeostase/fisiologia , Humanos , Cobre/metabolismo , Rim/metabolismo , Rim/fisiologia , Animais , Proteínas de Transporte de Cátions/metabolismo , Proteínas de Transporte de Cátions/fisiologia , Nefropatias/metabolismo , Adenosina Trifosfatases/metabolismo , Adenosina Trifosfatases/fisiologia , ATPases Transportadoras de Cobre/metabolismo , ATPases Transportadoras de Cobre/genética , Transportador de Cobre 1/metabolismo
19.
PLoS One ; 19(6): e0299088, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38829887

RESUMO

Although an increasing number of studies have examined issues relating to the preservation and development of intangible cultural heritage (ICH), there has been limited research on how tourists perceive ICH. Moreover, UNESCO asserts that the concept of "authenticity" is not applicable to ICH, and so far, no valid instrument for measuring tourists' subjective perceptions of ICH has been developed, even though their perceptions play a very important role in the preservation and development of ICH. Therefore, this paper aims to develop a measurement scale for ICH image, using both qualitative and quantitative research methods. Participant observation, semi-structured in-depth interviews, secondary data collection, and a literature review were conducted to generate the initial scale items, and then the main surveys were conducted to collect data for the model tests. Four dimensions were extracted by exploratory factor analysis: transmission, localization, vitality, and association. The reliability and validity of the measurement model were demonstrated through confirmatory factor analysis. We further determined that the transmission, vitality, and association of ICH image have a positive impact on tourists' revisit intention. The paper highlights the crucial role of ICH image in sustainable tourism development. The theoretical and managerial implications of the study are discussed, followed by suggestions for future research.


Assuntos
Turismo , Humanos , Feminino , Masculino , Adulto , Inquéritos e Questionários , Cultura , Reprodutibilidade dos Testes , Análise Fatorial , Pessoa de Meia-Idade
20.
J Phys Chem Lett ; 15(26): 6835-6840, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38917057

RESUMO

Organic-inorganic hybrid ternary copper halides offer a broader spectrum of structural possibilities for finely tuning their optoelectronic properties. Herein, we demonstrate for the first time the potential of [N(C2H5)4]2[Cu2Br4], a zero-dimensional hybrid copper halide [(TEA)2Cu2Br4], for ultraviolet (UV) photodetection. A self-powered, visible-blind UV photodetector based on a (TEA)2Cu2Br4/GaN heterojunction architecture is developed, exhibiting a high responsivity, a high detectivity, and fast response speeds. The device demonstrates exceptional stability against environmental oxygen/moisture, heat, and UV light illumination, surpassing the stability of reported copper-based UV photodetectors. Our work highlights the significant potential of (TEA)2Cu2Br4 as a lead-free, stable, and efficient material for next-generation UV photodetection technology.

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