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Cellulose hydrogels, formed either through physical or chemical cross-linking into a three-dimensional network from cellulose or its derivatives, are renowned for their exceptional water absorption capacities and biocompatibility. Rising demands for sustainable materials have spurred interest in cellulose hydrogels, attributed to their abundant supply, biodegradability, and non-toxic nature. These properties highlight their extensive potential across various sectors including biomedicine, the food industry, and environmental protection. Cellulose hydrogels are particularly advantageous in applications such as drug delivery, wound dressing, and water treatment. Recent large-scale studies have advanced our understanding of cellulose preparation and its applications. This review delves into the fundamental concepts, preparation techniques, and current applications of cellulose hydrogels in diverse fields. It also discusses the latest advances in nano-lignin-based hydrogels, providing a comprehensive overview of this promising material and offering insights and guidance for future research and development.
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The effects of 5-methyltetrahydrofolate (5-MTHF) on a rat model of Alzheimer's disease (AD) induced by D-galactose (D-gal) and aluminum chloride (AlCl3) were investigated. Wistar rats were given an i.p. injection of 60 mg/kg D-gal and 10 mg/kg AlCl3 to induce AD and three doses of 1 mg/kg, 5 mg/kg or 10 mg/kg 5-MTHF by oral gavage. A positive control group was treated with 1 mg/kg donepezil by gavage. Morris water maze performance showed that 5 and 10 mg/kg 5-MTHF significantly decreased escape latency and increased the number of platform crossings and time spent in the target quadrant for AD rats. The administration of 10 mg/kg 5-MTHF decreased the brain content of amyloid ß-protein 1-42 (Aß1-42) and phosphorylated Tau protein (p-Tau) and decreased acetylcholinesterase and nitric oxide synthase activities. Superoxide dismutase activity, vascular endothelial growth factor level and glutamate concentration were increased, and malondialdehyde, endothelin-1, interleukin-6, tumor necrosis factor-alpha and nitric oxide decreased. The administration of 10 mg/kg 5-MTHF also increased the expression of disintegrin and metallopeptidase domain 10 mRNA and decreased the expression of ß-site amyloid precursor protein cleavage enzyme 1 mRNA. In summary, 5-MTHF alleviates memory impairment in a D-gal- and AlCl3-exposed rat model of AD. The inhibition of Aß1-42 and p-Tau release, reduced oxidative stress, the regulation of amyloid precursor protein processing and the release of excitatory amino acids and cytokines may be responsible.
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Enfermedad de Alzheimer , Animales , Ratas , Acetilcolinesterasa/metabolismo , Cloruro de Aluminio/toxicidad , Enfermedad de Alzheimer/inducido químicamente , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/metabolismo , Péptidos beta-Amiloides/toxicidad , Precursor de Proteína beta-Amiloide/efectos adversos , Precursor de Proteína beta-Amiloide/metabolismo , Modelos Animales de Enfermedad , Galactosa/toxicidad , Hipocampo/metabolismo , Aprendizaje por Laberinto/fisiología , Trastornos de la Memoria/inducido químicamente , Trastornos de la Memoria/tratamiento farmacológico , Estrés Oxidativo , Ratas Wistar , ARN Mensajero/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismoRESUMEN
Atherosclerosis is a chronic inflammatory disease that leads to tissue ischemia. As the biologically active form of folic acid, L-5-methyltetrahydrofolate (L-5-MTHF) can improve endothelial function. And Seal oil plays a beneficial role in the progression of atherosclerosis. The study aims to evaluate beneficial effects of L-5-MTHF alone or in combination with Seal oil on atherosclerosis. Seventy-two male Wistar rats were randomly divided into 6 groups: control (normal diet), atherosclerosis (high-fat diet), folic acid (high-fat+3 mg/kg folic acid), low-dose L-5-MTHF (high-fat+3 mg/kg L-5-MTHF), low-dose L-5-MTHF+Seal oil (high-fat+3 mg/kg L-5-MTHF+0.5 g/kg Seal oil), high-dose L-5-MTHF (high-fat+10 mg/kg L-5-MTHF). After 13 wk, rats were sacrificed. Rats exhibiting atherosclerosis had dyslipidemia and serious aortic lesions. Supplementation with low-dose L-5-MTHF+Seal oil or use of high-dose L-5-MTHF increased serum folate concentrations, decreased homocysteine levels, improved the serum lipid profile, up-regulated expression of NO and NOS, enhancement of the antioxidant properties of GSH-Px activity and reduction in the concentration of MDA, levels of Olr1 and RelA mRNA decreased in aortic tissues, and expression of inflammatory factors, TNF-α, IL-6, IL-1ß and endothelial cell injury factors ET-1 and sICAM-1, were also down-regulated. In addition, HD-L-5-MTHF increased the antioxidant activity of serum SOD. We conclude that L-5-MTHF has obvious anti-inflammatory and antioxidant effects on diseased blood vessels. The intervention of L-5-MTHF alone or in combination with Seal oil can improve atherosclerosis in rats and reduce the occurrence of aortic lesions. The anti-atherosclerotic mechanism may be related to down-regulation of Olr1 and RelA expression.
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Aterosclerosis , Tetrahidrofolatos , Animales , Antioxidantes/farmacología , Aterosclerosis/tratamiento farmacológico , Aterosclerosis/etiología , Aterosclerosis/prevención & control , Ácido Fólico/farmacología , Masculino , Ratas , Ratas WistarRESUMEN
BACKGROUND: A balanced intake of trace elements is beneficial for chronic diseases such as hypertension. However, the available information regarding trace elements that may be independently associated with hypertension is limited, and the relationship between this disorder and element ratios also remains unclear. METHODS: A total of 6,754 subjects from rural China were selected, after exclusion of patients who were under 18, had incomplete data or had additional related disorders, by multi-stage simple random and cluster sampling (participation rate: 95.22 %). Subjects were divided into a hypertensive (H) and a control (C) group. Data were collected on blood pressure and 12 serum trace elements were measured by flame atomic absorption spectrometry and inductively coupled plasma-mass spectrometry. Other basic information was collated from questionnaires and biochemical indicators were measured via kits. RESULTS: Differences in serum levels of magnesium (Mg(mg/l): H: 27.43 ± 12.72; C: 26.33 ± 12.16), iron (Fe(mg/l): H: 1.99 ± 1.24; C: 1.84 ± 1.16), copper (Cu(mg/l): H: 1.19 ± 0.37; C: 1.10 ± 0.36), boron (B(µg/l): H: 50.00 ± 25.21; C: 47.57 ± 26.25), selenium (Se(µg/l): H: 125.12 ± 32.81; C: 118.80 ± 29.72) and chromium (Cr(µg/l): H: 8.77 ± 10.12; C: 10.12 ± 10.72) between the hypertensive and control groups were found. There were no differences in serum contents of calcium (Ca(mg/l): H: 112.43 ± 58.25; C: 111.00 ± 59.49), zinc (Zn(mg/l): H: 1.50 ± 1.97; C: 1.44 ± 1.88), arsenic (As(µg/l): H: 4.17 ± 3.94; C: 4.10 ± 4.00), manganese (Mn(µg/l): H: 4.15 ± 4.03; C: 4.07 ± 4.05), cadmium (Cd(µg/l): H: 1.14 ± 1.11; C: 1.18 ± 1.12) or lead (Pb(µg/l): H: 4.22 ± 8.90; C: 4.26 ± 10.25). The serum Cr and Cd concentrations of hypertensive men were lower than that of male controls while Mg, Cu, Ca and Se concentrations in male controls were lower. Further differences were apparent and Fe, B, Se, Mg and Cu all showed higher levels in hypertensive females whereas Cr concentrations were higher in female controls. Serum Zn and B levels showed age-related variations among hypertensive patients and concentrations of serum Cu, Zn, Se and B showed age-related variations among control subjects. For hypertensive patients, the odds ratio (OR) and 95 % confidence interval (CI) for the association of serum Cu, Se and Cr levels with hypertension were Cu: 1.36 (1.12-1.66); Se: 1.03 (1.01-1.05); Cr: 0.89 (0.83-0.96). Moreover, when the participants in the grouping with the highest copper/zinc (Cu/Zn) and magnesium/manganese (Mg/Mn) ratios were compared with the reference group, the OR and 95 % CI for hypertension were 1.22 (1.04-1.44) and 1.20 (1.01-1.42), respectively. CONCLUSIONS: Levels of serum trace elements showed age- and sex-related differences in a group of rural Chinese adults with hypertension and healthy participants. Serum concentrations of Cu, Se and Cr may be independently associated with hypertension. Higher serum ratios of Cu:Zn and Mg:Mn may also be associated with hypertension. Further randomized trials are necessary to elucidate the true relationship between levels of Cu, Se, Cr, Cu:Zn, Mg:Mn and hypertension.
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Exposición a Riesgos Ambientales/estadística & datos numéricos , Hipertensión , Oligoelementos , Cadmio , Cobre , Estudios Transversales , Femenino , Humanos , Hipertensión/epidemiología , Hipertensión/metabolismo , Magnesio , Masculino , Manganeso , Espectrofotometría Atómica , Oligoelementos/análisis , Oligoelementos/metabolismo , ZincRESUMEN
Functional aerogels composed of regenerated cellulose and tungsten oxide were fabricated by implanting tungsten-oxide nanodots into regenerated cellulose fiber. This superfast photochromic property benefitted from the small size and even distribution of tungsten oxide, which was caused by the confinement effect of the regenerated cellulose fiber. The composite was characterized using XRD and TEM to illustrate the successful loading of tungsten oxide. The composite turned from pale white to bright blue under ambient solar irradiation in five seconds. The evidence of solar absorption and electron paramagnetic resonance (EPR) demonstrated the fast photochromic nature of the composite and its mechanism. Furthermore, carbon fiber filled with preferential growth tungsten-oxide nanorods was obtained by annealing the photochromic composite in a N2 atmosphere. This annealed product exhibited good absorption across the whole solar spectrum and revealed an excellent photothermal conversion performance. The water evaporation rate reached 1.75 kg m-2 h-1 under one sun illumination, which is 4.4 times higher than that of pure water. The photothermal conversion efficiency was 85%, which shows its potential application prospects in seawater desalination.