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1.
Mol Med ; 30(1): 35, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38454322

RESUMO

BACKGROUND: Neuronal ferroptosis plays a critical role in the pathogenesis of cognitive deficits. The present study explored whether artemisinin protected type 2 diabetes mellitus (T2DM) mice from cognitive impairments by attenuating neuronal ferroptosis in the hippocampal CA1 region. METHODS: STZ-induced T2DM mice were treated with artemisinin (40 mg/kg, i.p.), or cotreated with artemisinin and Nrf2 inhibitor MEL385 or ferroptosis inducer erastin for 4 weeks. Cognitive performance was determined by the Morris water maze and Y maze tests. Hippocampal ROS, MDA, GSH, and Fe2+ contents were detected by assay kits. Nrf2, p-Nrf2, HO-1, and GPX4 proteins in hippocampal CA1 were assessed by Western blotting. Hippocampal neuron injury and mitochondrial morphology were observed using H&E staining and a transmission electron microscope, respectively. RESULTS: Artemisinin reversed diabetic cognitive impairments, decreased the concentrations of ROS, MDA and Fe2+, and increased the levels of p-Nr2, HO-1, GPX4 and GSH. Moreover, artemisinin alleviated neuronal loss and ferroptosis in the hippocampal CA1 region. However, these neuroprotective effects of artemisinin were abolished by Nrf2 inhibitor ML385 and ferroptosis inducer erastin. CONCLUSION: Artemisinin effectively ameliorates neuropathological changes and learning and memory decline in T2DM mice; the underlying mechanism involves the activation of Nrf2 to inhibit neuronal ferroptosis in the hippocampus.


Assuntos
Artemisininas , Disfunção Cognitiva , Diabetes Mellitus Tipo 2 , Ferroptose , Animais , Camundongos , Fator 2 Relacionado a NF-E2 , Espécies Reativas de Oxigênio , Disfunção Cognitiva/tratamento farmacológico , Disfunção Cognitiva/etiologia , Hipocampo , Artemisininas/farmacologia , Artemisininas/uso terapêutico , Neurônios
2.
Nanoscale ; 16(9): 4866-4871, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38315558

RESUMO

Owing to its stable graphene-like honeycomb structure, suitable band gap, and nontoxicity, SnC monolayer (ML) has attracted increasing attention in photocatalytic applications. One pertinent obstacle inherent to SnC ML-based photocatalysts has been the high energy barrier in hydrogen evolution reaction (HER) that always requires external energy input and/or strongly acidic conditions. Herein, we propose a two-dimensional (2D) SnC/ZrS2 van der Waals heterostructure (vdWHS) for highly efficient photocatalytic water splitting using first-principles calculations. The results show that the pristine vdWHS is an S-scheme heterostructure that works in acidic conditions for water splitting owing to the high energy barrier in HER. Notably, detailed further investigations show that doping Si in the SnC ML of the vdWHS can solve this high barrier problem, leading to a high-performance low-cost photocatalyst. Our work offers a convenient strategy to solve the notorious high barrier problem in HER that often troubles the SnC ML and other 2D materials such as transition metal dichalcogenide MLs for the design and fabrication of highly efficient photocatalysts.

4.
Cancer Cell ; 41(11): 1927-1944.e9, 2023 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-37738973

RESUMO

Although polymorphic microbiomes have emerged as hallmarks of cancer, far less is known about the role of the intratumor mycobiome as living microorganisms in cancer progression. Here, using fungi-enriched DNA extraction and deep shotgun metagenomic sequencing, we have identified enriched tumor-resident Aspergillus sydowii in patients with lung adenocarcinoma (LUAD). By three different syngeneic lung cancer mice models, we find that A. sydowii promotes lung tumor progression via IL-1ß-mediated expansion and activation of MDSCs, resulting in suppressed activity of cytotoxic T lymphocyte cells and accumulation of PD-1+ CD8+ T cells. This is mediated by IL-1ß secretion via ß-glucan/Dectin-1/CARD9 pathway. Analysis of human samples confirms that enriched A. sydowii is associated with immunosuppression and poor patient outcome. Our findings suggest that intratumor mycobiome, albeit at low biomass, promotes lung cancer progression and could be targeted at the strain level to improve patients with LUAD outcome.


Assuntos
Neoplasias Pulmonares , Micobioma , Células Supressoras Mieloides , Humanos , Animais , Camundongos , Neoplasias Pulmonares/genética , Linfócitos T CD8-Positivos , Pulmão
5.
Nanomaterials (Basel) ; 13(12)2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37368292

RESUMO

GeSe monolayer (ML) has recently attracted much interest due to its unique structure and excellent physical properties that can be effectively tuned through single doping of various elements. However, the co-doping effects on GeSe ML are rarely studied. In this study, the structures and physical properties of Mn-X (X = F, Cl, Br, I) co-doped GeSe MLs are investigated by using first-principle calculations. The formation energy and phonon disspersion analyses reveal the stability of Mn-Cl and Mn-Br co-doped GeSe MLs and instability of Mn-F and Mn-I co-doped GeSe MLs. The stable Mn-X (X = Cl, Br) co-doped GeSe MLs exhibit complex bonding structures with respect to Mn-doped GeSe ML. More importantly, Mn-Cl and Mn-Br co-doping can not only tune magnetic properties, but also change the electronic properties of GeSe MLs, which makes Mn-X co-doped GeSe MLs indirect band semiconductors with anisotropic large carrier mobility and asymmetric spin-dependent band structures. Furthermore, Mn-X (X = Cl, Br) co-doped GeSe MLs show weakened in-plane optical absorption and reflection in the visible band. Our results may be useful for electronic, spintronic and optical applications based on Mn-X co-doped GeSe MLs.

6.
Nanoscale ; 15(5): 2206-2213, 2023 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-36537226

RESUMO

Fe-doped SiGe (Si0.25Ge0.75:Fex, x = 0.01, 0.025, and 0.05) thin films were prepared by radio frequency magnetron sputtering and subsequent rapid thermal annealing on a Ge (100) substrate and their structural, magnetic and magneto-transport properties were investigated. Structural characterization using AFM, SEM, XRD, and HRTEM shows that the obtained samples are polycrystalline and their lattice constants increase with the Fe concentration. Analysis of their electronic and spintronic states using XPS and XMCD reveals that Fe dopants mainly exist as substitutional Fe2+ ions in the SiGe lattice, providing both local magnetic moments and hole carriers. Furthermore, magnetization measurements indicate that all the samples exhibit ferromagnetism, and their Curie temperature increases with the Fe concentration up to 294 K; meanwhile, magneto-transport measurements reveal a giant magnetoresistance (GMR) effect of over 800% and an anomalous Hall effect (AHE), as well as semiconducting behaviors, in the samples. Further analysis suggests that the ferromagnetism comes from a hole-mediated process originating from substitutional Fe dopants in the SiGe matrix and this is enhanced by the tensile strain in the films. The synthesis and high-temperature ferromagnetism of Fe-doped SiGe thin films may play a key role in group IV-based spintronic applications.

7.
Front Pharmacol ; 13: 991597, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36238549

RESUMO

Intestinal aging seriously affects the absorption of nutrients of the aged people. Ginsenoside Rb1 (GRb1) which has multiple functions on treating gastrointestinal disorders is one of the important ingredients from Ginseng, the famous herb in tradition Chinese medicine. However, it is still unclear if GRb1 could improve intestinal aging. To investigate the function and mechanism of GRb1 on improving intestinal aging, GRb1 was administrated to 104-week-old C57BL/6 mice for 6 weeks. The jejunum, colon and feces were collected for morphology, histology, gene expression and gut microbiota tests using H&E staining, X-gal staining, qPCR, Western blot, immunofluorescence staining, and 16S rDNA sequencing technologies. The numbers of cells reduced and the accumulation of senescent cells increased in the intestinal crypts of old mice, and administration of GRb1 could reverse them. The protein levels of CLDN 2, 3, 7, and 15 were all decreased in the jejunum of old mice, and administration of GRb1 could significantly increase them. The expression levels of Tert, Lgr5, mKi67, and c-Myc were all significantly reduced in the small intestines of old mice, and GRb1 significantly increased them at transcriptional or posttranscriptional levels. The protein levels of SIRT1, SIRT3, and SIRT6 were all reduced in the jejunum of old mice, and GRb1 could increase the protein levels of them. The 16S rDNA sequencing results demonstrated the dysbiosis of the gut microbiota of old mice, and GRb1 changed the composition and functions of the gut microbiota in the old mice. In conclusion, GRb1 could improve the intestinal aging via regulating the expression of Sirtuins family and modulating the gut microbiota in the aged mice.

8.
Artigo em Inglês | MEDLINE | ID: mdl-36159565

RESUMO

Objective: We aim to explore the clinical therapeutic effect of alternative wave electroacupuncture combined with Lee's naprapathy therapy on knee osteoarthritis (KOA) (blood stasis due to qi stagnation). Method: 122 patients with KOA treated in our hospital from January 2018 to October 2021 were randomly grouped into a combined group (n = 61) and a control group (n = 61). The combined group was treated with alternative wave electroacupuncture combined with Lee's naprapathy, while the control group was treated with alternative wave electroacupuncture alone. Clinical efficacy of the two groups was observed. The Visual Analogue Scale (VAS), Lysholm Scale, Indexes of Severity for Osteoarthritis (ISOA), and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) were compared before and after treatment, followed up for 3 months and 6 months. The adverse reactions of the two groups were observed. Result: The overall response rate of the combined group (96.72%) was higher than that of the control group (81.97%), and the difference was statistically significant (P < 0.05). After treatment and follow-up for 3 months and 6 months, the Lysholm score of the combined group was higher than that of the control group, while the VAS, ISOA, and WOMAC scores were lower than those of the control group, and the difference between the two was statistically significant (P < 0.05). There were no serious adverse reactions in both groups (P > 0.05). Conclusion: The alternative wave electroacupuncture combined with Lee's naprapathy is effective and safe in treating KOA (blood stasis due to qi stagnation).

9.
Toxicology ; 477: 153278, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35926757

RESUMO

Loperamide is a non-prescription medicine normally used for the treatment of diarrhea. The abuse and misuse of loperamide have been demonstrated to have toxic effects on heart. It is still unclear whether the abuse of loperamide can cause hepatic toxicity. The C57BL/6 mice fed with high fat diet (HFD) or normal food diet (NFD) were administrated with loperamide (5 mg/kg/day) intragastrically once a day for two weeks, after that, the feces, blood, hepatic tissues and intestines were harvested for biochemical and histological detection, and the expression of genes related with lipid metabolism was further checked by qRT-PCR (quantitative real-time polymerase chain reaction) and Western blot. The administration of loperamide caused the constipation in mice fed with NFD or HFD. The content of bile acids was significantly reduced in the feces of mice treated with loperamide, but the content of bile acids was significantly increased in the liver of these mice. The results of H&E staining showed that loperamide administration caused the damage of hepatic tissues, especially for mice fed with HFD. The expression of genes related with the biosynthesis of cholesterol and bile acids, including Hmgcr, Lss, Sqle, Fdps, Idi1, Mvk, Cyp7a1 and Ch25h, was all upregulated in the liver of mice treated with loperamide. Conversely, the expression of Abcg5, Abcb11 and Abcc2, which encode genes for transporting cholesterols and bile acids from hepatocytes to bile respectively, was downregulated in the liver of mice treated with loperamide. At the same time, the expression of Fabp6 and Slc51a, which transport bile acids from intestinal lumen into the blood, was all upregulated in the ileum of mice treated with loperamide. The expression of SHP, which inhibits the transcription of Cyp7a1 in hepatocytes, was significantly downregulated in the hepatic tissues of mice treated with loperamide. These results demonstrated that administration of loperamide caused excessive accumulation of bile acids in the liver of mice via upregulating genes for biosynthesis of cholesterol and bile acid and downregulating genes for discharging cholesterol and bile acids in hepatocytes of mice, moreover, the downregulation of SHP in hepatic tissues might be one of the mechanisms of it, especially for mice fed with HFD.


Assuntos
Ácidos e Sais Biliares , Loperamida , Animais , Ácidos e Sais Biliares/metabolismo , Colesterol/metabolismo , Dieta Hiperlipídica , Fígado , Loperamida/metabolismo , Loperamida/toxicidade , Camundongos , Camundongos Endogâmicos C57BL
11.
Front Immunol ; 13: 843378, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35493520

RESUMO

EpCAM deficiency causes congenital tufting enteropathy (CTE) which is considered as one kinds of very early onset inflammatory bowel disease (IBD). However, functions of EpCAM on regulating the immunity of intestines are still unclear. To study the mechanism of EpCAM on maintaining the intestinal immune homeostasis, the intestines of WT and EpCAM-/- mice at E18.5, P0 and P3 stages were collected for morphological, histological and gene expression tests. Serious inflammation was detected in the small intestines of P3 EpCAM-/- mice. Compared to WT mice, genes related to inflammatory factors and immunity cells, including TNFα, IL-1ß, IL-6, IL-8rb, MIP2, MCP1, Ly6d and Ly6g, were all significantly upregulated and the expression of intestinal abundance matrix metalloproteinases (MMPs) was also significantly increased in the intestines of EpCAM-/- mice at E18.5, P0 and P3 stages. Signals of p38, ERK1/2 and JNK were hyper-activated in the intestines of EpCAM-/- mice. The expression of pIgR was significantly decreased and the expression and activation of transcriptional factors which promote the expression of pIgR were also reduced in the intestines of EpCAM-/- mice compared to WT controls. In conclusion, EpCAM could maintain the immune homeostasis of intestines via keeping the expression of pIgR in the intestinal epithelium.


Assuntos
Diarreia Infantil , Mucosa Intestinal , Animais , Molécula de Adesão da Célula Epitelial/genética , Homeostase , Humanos , Lactente , Mucosa Intestinal/metabolismo , Intestinos/patologia , Camundongos
12.
Bioorg Med Chem ; 53: 116520, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34847494

RESUMO

The increase of concentrations of total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) in the serum of postmenopausal women is the important risk factor of the high morbidity of cardiovascular diseases of old women worldwide. To test the anti-hypercholesterolemia function of dihydroartemisinin (DHA) in postmenopausal women, ovariectomized (OVX) mice were generated, and DHA were administrated to OVX mice for 4 weeks. The blood and liver tissues were collected for biochemical and histological tests respectively. The mRNA and protein expression levels of genes related to metabolism and transport of cholesterol, bile acid and fatty acid in the liver or ileum were checked through qPCR and western blot. DHA could significantly reduce the high concentrations of TC and LDL-C in the serum and the lipid accumulation in the liver of ovariectomized mice. The expression of ABCG5/8 was reduced in liver of OVX mice, and DHA could up-regulate the expression of them. Genes of transport proteins for bile salt transport from blood to bile, including Slc10a1, Slco1b2 and Abcb11, were also significantly up-regulated by DHA. DHA also down-regulated the expression of Slc10a2 in the ileum of OVX mice to reduce the absorption of bile salts. Genes required for fatty acid synthesis and uptake, such as Fasn and CD36, were reduced in the liver of OVX mice, and DHA administration could significantly up-regulate the expression of them. These results demonstrated that DHA could improve hypercholesterolemia in OVX mice through enhancing the vectorial transport of cholesterol and bile acid from blood to bile.


Assuntos
Anticolesterolemiantes/farmacologia , Artemisininas/farmacologia , Ácidos e Sais Biliares/metabolismo , Bile/metabolismo , Colesterol/metabolismo , Hipercolesterolemia/tratamento farmacológico , Animais , Anticolesterolemiantes/química , Artemisininas/química , Bile/química , Ácidos e Sais Biliares/sangue , Transporte Biológico Ativo/efeitos dos fármacos , Colesterol/sangue , Relação Dose-Resposta a Droga , Feminino , Hipercolesterolemia/patologia , Hipercolesterolemia/cirurgia , Camundongos , Camundongos Endogâmicos C57BL , Estrutura Molecular , Ovariectomia , Relação Estrutura-Atividade
13.
Nanotechnology ; 33(41)2022 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-34911044

RESUMO

The structural and electronic properties of two-dimensional (2D) SiAs2/GeAs2van der Waals heterostructure (vdWH) and its applications are investigated by combing first-principles calculations and Silvaco Atlas simulations. The stable SiAs2/GeAs2vdWH exhibits an indirect bandgap of 0.99 eV in type II band alignment for light detection and energy harvesting. The vdWH can exhibit a direct bandgap up to 0.66 eV by applying an appropriate electric field (Eext). Due to theEextinduced charge redistribution, its band alignment can be transformed from type II to type I for light-emitting. Further simulation shows that the band alignment of SiAs2/GeAs2vdWH can be tuned back and forth between type II and type I by gate voltage in a single field-effect transistor for multiple functional applications. These results may be useful for applications of the SiAs2/GeAs2heterostructure in future electronic and optoelectronic devices.

14.
Front Endocrinol (Lausanne) ; 12: 708838, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34276568

RESUMO

The lower incidence of metabolic diseases of women than men and the increasing morbidity of metabolic disorders of menopausal women indicated that hormones produced by ovaries may affect homeostasis of glucose and lipid metabolism, but the underlying mechanisms remain unclear. To explore the functions of ovaries on regulating glucose and lipid metabolism in females, 8 weeks old C57BL/6 mice were preformed ovariectomy and administrated with normal food diet (NFD) or high fat diet (HFD). Six weeks after ovariectomy, blood biochemical indexes were tested and the morphology and histology of livers were checked. The expression levels of genes related to glucose and lipid metabolism in liver were detected through transcriptome analysis, qPCR and western blot assays. 16S rDNA sequence was conducted to analyze the gut microbiota of mice with ovariectomy and different diets. The serum total cholesterol (TC) was significantly increased in ovariectomized (OVX) mice fed with NFD (OVXN), and serum low density lipoprotein-cholesterol (LDL-C) was significantly increased in both OVXN mice and OVX mice fed with HFD (OVXH). The excessive glycogen storage was found in livers of 37.5% mice from OVXN group, and lipid accumulation was detected in livers of the other 62.5% OVXN mice. The OVXN group was further divided into OVXN-Gly and OVXN-TG subgroups depending on histological results of the liver. Lipid drops in livers of OVXH mice were more and larger than other groups. The expression level of genes related with lipogenesis was significantly increased and the expression level of genes related with ß-oxidation was significantly downregulated in the liver of OVXN mice. Ovariectomy also caused the dysbiosis of intestinal flora of OVXN and OVXH mice. These results demonstrated that hormones generated by ovaries played important roles in regulating hepatic glucose and lipid metabolism and communicating with the gut microbiota in females.


Assuntos
Disbiose/patologia , Microbioma Gastrointestinal , Glucose/metabolismo , Homeostase , Lipídeos/análise , Ovariectomia/efeitos adversos , Animais , Dieta Hiperlipídica , Disbiose/microbiologia , Feminino , Camundongos , Camundongos Endogâmicos C57BL
15.
Iran J Basic Med Sci ; 24(5): 629-635, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34249264

RESUMO

OBJECTIVES: Sirt3 may regulate ROS production and might be involved in ß-cell apoptosis, which plays an important role in the progression of type 2 diabetes mellitus (T2DM). Quercetin is a potent anti-oxidative bioflavonoid, but its effects on T2DM remain to be explored. This study aimed to investigate the effects of quercetin on ß-cell apoptosis and explore its mechanisms. MATERIALS AND METHODS: The effects of quercetin were conducted on db/db mice and INS1 cells. Fasting blood glucose was determined by the colorimetric method, serum insulin was measured by enzyme-linked immunosorbent assay (ELISA). Meanwhile, Sirt3 in INS1 cells was knocked down by plasmid transfection. The antioxidant proteins (SOD2 and CAT), apoptosis proteins (cleaved Caspase-3, Bax, and BCL-2), and Sirt3 protein in pancreases and INS1 cells were determined by western blotting. RESULTS: When INS1 cells and diabetic mice were treated with quercetin, the levels of SOD2, CAT, and Sirt3 proteins were increased, the levels of cleaved Caspase-3 and the ratio of Bax to BCL-2 were decreased at different degrees, along with reduced blood glucose levels and elevated insulin levels in diabetic mice. When Sirt3 was knocked down in INS1 cells, increase of two antioxidants and decrease of cell apoptosis generated by quercetin could not occur. CONCLUSION: Quercetin protected islet ß-cells from oxidation-induced apoptosis via Sirt3 in T2DM, which would be beneficial to develop new strategies for preventing ß-cell failure in T2DM.

16.
Phys Chem Chem Phys ; 23(23): 13323-13330, 2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34096566

RESUMO

Vertical van der Waals heterojunctions (HJs) composed of a photocatalytic star material BiOCl monolayer and group-IV Xene monolayer (silicene, germanene etc.) were studied by using first-principles calculations. Formation energy analysis and molecular dynamics simulation show that the BiOCl/Xene bilayer HJs can exist stably up to room temperature. Owing to evident charge redistribution and accumulation occurring between the bilayers, electron-hole puddles form and charge carrier transfer and separation occur in the HJs, which are beneficial to the improvement of photocatalytic performance. The HJ energy bands maintain the Dirac cones with almost linear dispersion curves, suggesting low effective mass and high mobility of carriers, and can be effectively tuned by strain. Our results show that the BiOCl/Xene bilayer HJs with high separation efficiency and high mobility of carriers and strain-adjustable bandgaps provide varieties in the functionalities of 2D van der Waals HJs and show great potentials in photocatalytic applications.

17.
Toxicology ; 450: 152678, 2021 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-33440193

RESUMO

Exposure of humans to second-hand smoking (SHS) increases glucose and lipid metabolic disorders. The link of hepatic metabolic dysfunction to environmental cigarette smoking has been noticed, but the related mechanism is still unclear. C57BL/6 mice with normal food diet (NFD) or high fat diet (HFD) were exposed to 15 min cigarette smoking twice a day in a 0.038 m3 box for 4 weeks, and the concentration of nicotine in the air of the box was 21.05 mg/m3 during the smoke exposure. Liver tissues and serum were collected for gene expression and biochemistry test. The fecal microbiota was also checked through 16S rDNA sequences. Cigarette smoking exposure increased the accumulation of total cholesterol (TC) in liver, and the expression of cholesterol synthesis-related genes was upregulated. The expression of CYP8B1 protein was significantly down-regulated, and the ratio of cholic acid (CA) to chenodeoxycholic acid (CDCA) was significantly reduced in the liver of mice exposed to cigarette smoking especially for HFD group. Cigarette smoking exposure caused insulin resistance in the liver of mice with HFD. The composition of the gut microbiota was altered with the exposure of cigarette smoking, and the change of the distribution of primary bile acids might be one of the reasons. It was concluded that cigarette smoking would break the homeostasis of cholesterol and bile acids metabolism and changed the composition of gut microbiota. Our discoveries confirmed that smoking bans are important for the public health.


Assuntos
Ácidos e Sais Biliares/metabolismo , Colesterol/metabolismo , Fumar Cigarros/efeitos adversos , Dieta Hiperlipídica/efeitos adversos , Disbiose/metabolismo , Microbioma Gastrointestinal/fisiologia , Animais , Disbiose/induzido quimicamente , Microbioma Gastrointestinal/efeitos dos fármacos , Homeostase/efeitos dos fármacos , Homeostase/fisiologia , Exposição por Inalação/efeitos adversos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Poluição por Fumaça de Tabaco/efeitos adversos
18.
Chem Sci ; 11(8): 2193-2199, 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34123311

RESUMO

Herein, we report a three-dimensional (3D) DNA walking nanomachine innovatively constructed from a functionalized 3D DNA track, which runs in an orderly manner with favorable directionality to allow for programming certain pathways of information transduction for some target tasks. The nanomachine was constructed using a departure station of walker (UB + W) and a functionalized 3D track, which was made up of a rolling circle amplification (RCA)-generated backbone chain and numerous triangular rung units with stators (UA + S) assembled into a repeating array along the backbone. A specific domain (SD) was designed at the 5'-end of the backbone to capture the UB + W, and stators with specific RNA substrates were immobilized at the three UA corners for the DNA walker to travel on. Powered by 10-23 DNAzyme, the DNA walker started moving from the SD end to the other end of the track by the autonomous cleavage of RNA substrates. Significantly, the homogeneous distribution of stators in the longitudinal and horizontal extensions paved a specific path for each walker to move along the 3D track. This resulted in random and inactive self-avoiding walking; thus, the nanomachine exhibited good executive ability. These properties allowed the DNA walking nanomachine to program the certain pathways of information transduction for the stepwise and programmed execution of some target tasks, such as the synthesis of specific polyorganics and cargo delivery. We believe that such a 3D DNA walking nanomachine could enrich the concept in the field of dynamic DNA nanotechnology, and may improve the development of novel DNA nanomachines in cargo delivery and composite product synthesis.

19.
RSC Adv ; 10(20): 11990-11993, 2020 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-35496615

RESUMO

Microwave plasma chemical vapor deposition (MPCVD) has been traditionally used to synthesize carbon-based materials such as diamonds, carbon nanotubes and graphene. Here we report that a rapid and catalyst-free growth of SnSe thin films can be achieved by using single-mode MPCVD with appropriate source materials. The analysis combining microscope images, X-ray diffraction patterns and lattice vibration modes shows that the grown thin films were composed of orthorhombic structured SnSe polycrystals. Further thermoelectric (TE) characterization of the SnSe films reveals the high-performance power factor of 3.98 µW cm-1 K-2 at 600 K. Our results may open an avenue for rapid synthesis of new types of materials such as IV-VI compounds and be useful for TE application of these materials.

20.
CNS Neurosci Ther ; 26(2): 167-176, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31423743

RESUMO

AIMS: Our previous study indicated that chronic stress caused autophagy impairment and subsequent neuron apoptosis in hippocampus. However, the mechanism underlying the stress-induced damage to neurons is unclear. In present work, we investigated whether stress-level glucocorticoids (GCs) GCs promoted PC12 cell damage via AMPK/mTOR signaling-mediated autophagy. METHODS: Chronic stress-induced PC12 cell injury model was built by treatment with high level corticosterone (CORT). Cell injury was evaluated by flow cytometry assay and transmission electron microscopy observation. RESULTS: Autophagy flux was measured based on the changes in LC3-II and P62 protein expressions, and the color alteration of mCherry-GFP-LC3-II transfection. Our results showed that CORT not only increased cell injury and apoptosis, but also dysregulated AMPK/mTOR signaling-mediated autophagy flux, as indicated by the upregulated expression of LC3-II and P62 proteins, and the lowered ration of autolysosomes to autophagosomes. Mechanistically, our results demonstrated that autophagy activation by AMPK activator metformin or mTOR inhibitor rapamycin obviously promotes cell survival and autophagy flux, improved mitochondrial ultrastructure, and reduced expression of Cyt-C and caspase-3 in CORT-induced PC12 cells. CONCLUSION: These results indicate that high CORT triggers PC12 cell damage through disrupting AMPK/mTOR-mediated autophagy flux. Targeting this signaling may be a promising approach to protect against high CORT and chronic stress-induced neuronal impairment.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Autofagia/efeitos dos fármacos , Corticosterona/toxicidade , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/genética , Animais , Apoptose/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Citometria de Fluxo , Lisossomos/efeitos dos fármacos , Metformina/farmacologia , Proteínas Associadas aos Microtúbulos/metabolismo , Células PC12 , Fagossomos/efeitos dos fármacos , Ratos , Sirolimo/farmacologia , Serina-Treonina Quinases TOR/antagonistas & inibidores
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