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Metal halide perovskite nanocrystals (NCs) have been widely studied for application in photonics and optoelectronics due to their excellent photoelectric properties. Perovskite NCs with narrow luminescence linewidth and high photoluminescence quantum yield are excellent assembly modules for building large-scale NC superlattices. The coupling of optics and electricity in such excellent aggregates gives them exceptional collective photoelectric performance, such as superfluorescence, red-shifted emission, coupling-enhanced electron transport, etc. Perovskite NC superlattices are expected to become another hot research topic in optoelectronics. Here, we focus on the collective behavior of superlattices and review the recent progress of the self-assembly, collective photoelectric properties, and applications of perovskite NC superlattices. Finally, a few challenges and prospects are indicated.
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Traditional Bas-relief modeling methods are often limited to inefficient and difficult to be altered after the product is formed. This paper presents a novel method for bas-relief modeling from RGB monocular images with regional division characteristics. The problem discussed in this paper involves edge detection, region division, height value recovery and three-dimensional reconstruction of image. In our framework, we can automatically obtain the pixel height of each area in the image and can adjust the concave-convex relationship of each image area to obtain a bas-relief modeling which can be printed directly in 3D. The edge detection algorithm used Gaussian difference pyramid to combine the luminance information and chrominance information of digital image; the regions of the RGB monocular image are divided by the improved connected-component labeling algorithm;and the 3D pixel point cloud of each region is calculated by the shape-from-shading algorithm. Different from previous work, our method can fully obtain the image height field data and completely restored the depth information,which makes it possible to use any RGB monocular image for bas-relief modeling. Experiments with groups of images show that our method can effectively generate bas-relief modeling.
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This paper discusses the short-term memory of vibro-tactile perception of human fingertips. By using a self-developed vibro-tactile expression device, a recall experiment was firstly carried out among 20 subjects aged 20-30 (10 males and 10 females) to discover the memory span about the vibro-tactile perception of human fingertips. Within this memory span, a cognitive experiment analyzing the recognition accuracy and the reaction time was carried out. The results showed: (1) The vibro-tactile memory span of human fingertip is 4 ± 1; (2) The vibro-tactile memory span increases as the discrete intensity between vibration stimuli increases; (3) Too long or too short vibration duration will reduce the vibro-tactile memory span, and the optimal vibration duration for men is 400 ms, for women is 300 ms; (4) The more the number of vibration stimuli is perceived by the human fingertip, the lower the recognition accuracy and the longer the reaction time it needs; (5) Compared with the vibration stimuli in disorder, people are more likely to remember the vibration stimuli in increasing/decreasing order; (6) The information extraction mechanism of the short-term memory about fingertip vibro-tactile perception bases a point to point scanning process among these stimuli. These results help to understand the human fingertip tactile characteristics and provide a physiological basis for the study of tactile feedback technologies.
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Memoria a Corto Plazo , Percepción del Tacto , Adulto , Femenino , Dedos , Humanos , Masculino , Tacto , Vibración , Adulto JovenRESUMEN
Alzheimer's disease (AD) is a progressive neurodegenerative disorder associated with synaptic dysfunction, pathological accumulation of ß-amyloid peptide 1-42 (Aß1-42 ), and neuronal loss. The self-association of Aß1-42 monomers (Aß-M) into soluble oligomers seems to be crucial for the development of neurotoxicity. Previous publications have shown that Aß oligomers and dimers might play key roles in inducing AD. The role of Aß-M was rarely investigated and still unclear in AD. To understand the effects of Aß-M on neurons and other cell types in the brain could be the key to understand its function. In our study, we found that Aß-M expression slowly induced cell apoptosis within 48 hours after transfection, ß2 adrenergic receptor (ß2AR) interacted with Aß-M in the pull-down and the yeast two-hybrid assays, and Aß-M played a major role in inducing phosphorylation of Tau at Ser-214, c-Jun N-terminal kinase (JNK) at Thr-183/Tyr-185, p70 ribosomal protein S6 kinase (p70S6K) at Thr-389. We also discovered that ß2AR, G protein-coupled receptor kinase 2 (GRK2), and protein kinase A (PKA) mediated the phosphorylation of Tau and JNK. Aß-M induced phosphorylation of Tau at Ser-214 through both ß2AR-cAMP/PKA-JNK and ß2AR-GRK signaling pathways. Mitogen-activated protein kinase kinase (MEK) mediated the phosphorylation of p70S6K induced by Aß-M.
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Enfermedad de Alzheimer/metabolismo , Péptidos beta-Amiloides/metabolismo , Fragmentos de Péptidos/metabolismo , Receptores Adrenérgicos beta 2/metabolismo , Transducción de Señal , Proteínas tau/metabolismo , Proteínas Quinasas Activadas por AMP/metabolismo , Animales , Apoptosis , Línea Celular Tumoral , Células Cultivadas , Humanos , MAP Quinasa Quinasa 4/metabolismo , Ratones , FosforilaciónRESUMEN
OBJECTIVE: To investigate the effects of Tangnaikang (TNK), a mixture of five herbal plant extracts, on inflammation-mediated insulin resistance and B-cell apoptosis in SHR.Cg-Leprcp/NDmcr (SHR-cp) rats. METHODS: Seven-week-old SHR-cp rats were randomly divided into a control (CON) group and a TNK (3.24 g/kg) group. Wistar-Kyoto rats at the same age were used as the normal control group. After 7 weeks of continuous intragastric administration of TNK, the glucose metabolic status and insulin sensitivity of the rats were evaluated by assessing fasting serum glucose (FBG), the oral glucose tolerance test (OGTT), fasting serum insulin (FINS), and the insulin sensitivity index (ISI). Serum tumor necrosis factor-a (TNF-a), interleukin-6 (IL-6), C-reactive protein (CRP) and adiponectin were measured via enzyme-linked immunosorbent assays. Macrophage infiltration and apoptosis in adipose tissues were detected through F4/80 immunohistochemistry and the terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. Islet morphology and B-cell apoptosis were investigated using double immunofluorescence staining and the TUNEL assay. The expression of cytokine genes in adipose tissue, the liver, and the pancreas was detected in real-time polymerase chain reaction assays. The expression and phosphorylation levels of insulin signaling-, inflammation-, and B-cell survival-related proteins in the liver and pancreas of SHR-cp rats were detected by western blotting. RESULTS: TNK (3.24 g/kg) treatment significantly decreased body weight, FBG and FINS; improved impaired glucose tolerance; increased the ISI; reduced serum levels of TNF-a, CRP and IL-6; and increased serum adiponectin. The mRNA expression of inflammatory markers was markedly reduced in the liver, pancreas, and adipose tissue. F4/80- and TUNEL-positive cells in adipose tissues were decreased, as was the number of TUNEL-positive B-cells. The phosphorylation of c-Jun N-terminal kinase and that of insulin receptor substrate-1 at serines 307 and 1101 was significantly decreased. In the pancreas, the expression of nuclear factor kappa-light chain-enhancer of activated B cells-p65 was significantly decreased, and phosphoinositide 3-kinase and IRS-2 were significantly increased. CONCLUSION: TNK was able to improve insulin resistance and B-cell apoptosis in SHR-cp rats, which might be associated with its ability to relieve the overall and local metabolic inflammatory responses observed in SHR-cp rats.
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OBJECTIVE: To assess the effect of a mixture of five herbal extracts (FT-5) on insulin resistance, glucose/lipid metabolism, hepatic steatosis, and to investigate whether the combination of FT-5 and pioglitazone would provide a robust effect on diabetes treatment, while may minimize undesirable side-effects of pioglitazone in diabetic Ay gene (KKAy) mice. METHODS: Seven-week-old KKAy mice were randomly divided into five groups: control (CON) group, FT-5 (2.0 g/kg) group, pioglitazone (20 mg/kg) (PIO) group, pioglitazone (20 mg/kg) + FT-5 (2.0 g/kg) (P + F) group. Age-matched C57BL/6J mice were used as the control group. After seven weeks of continuous intragastric administration of medication, the glucose metabolism, insulin sensitivity and lipid metabolism of KKAy mice were evaluated by assessing the fasting blood glucose (FBG), oral glucose tolerance test (OGTT), fasting serum insulin (FINS), insulin tolerance test (ITT), homeostasis model of assessment-insulin resistance index (HOMA-IR), total cholesterol (TC), total triglycerides (TG), and free fatty acids (FFA) in plasma and liver. Plasma and hepatic adiponectin were measured via enzyme-linked immunosorbent assays. Genes related to adipogenesis and lipolysis in white adipose tissues (WAT) and liver were examined by real-time polymerase chain reaction. Lipid metabolism-related protein expression in the liver of KKAy mice were detected by Western blotting. RESULTS: PIO treatment remarkably improved insulin resistance. However, it also showed substantial side effects. FT-5 group exhibited no significant decrease in serum glucose. However, it reduced fasting plasma TG levels and improved hepatic steatosis of KKAy mice. P + F group showed improved insulin resistance and similar body weight gain, as compared with control group. The mRNA expression of genes related to fatty acid oxidation was markedly up-regulated in the liver of P + F group. Pioglitazone administration markedly decreased the phosphorylation levels of AMPK, as compared with all other groups. Besides, even though plasma adiponectin increased in PIO, FT-5, P + F group, adipoR2 gene expression significantly decreased in the liver of PIO group. CONCLUSION: FT-5 decreased plasma TG and alleviated aggravating hepatic steatosis induced by pioglitazone in KKAy mice. FT-5's mechanism might be associated with its ability to activate the AdipoR2/AMPK pathway.
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Increased energy intake and reduced physical activity can lead to obesity, diabetes and metabolic syndrome. Transcriptional modulation of metabolic networks has become a focus of current drug discovery research into the prevention and treatment of metabolic disorders associated with energy surplus and obesity. Tang-Nai-Kang (TNK), a mixture of five herbal plant extracts, has been shown to improve abnormal glucose metabolism in patients with pre-diabetes. Here, we report the metabolic phenotype of SHR.Cg-Leprcp/NDmcr (SHR/cp) rats treated with TNK. Pre-diabetic SHR/cp rats were randomly divided into control, TNK low-dose (1.67 g/kg) and TNK high-dose (3.24 g/kg) groups. After high-dose treatment for 2 weeks, the serum triglycerides and free fatty acids in SHR/cp rats were markedly reduced compared to controls. After 3 weeks of administration, the high dose of TNK significantly reduced the body weight and fat mass of SHR/cp rats without affecting food consumption. Serum fasting glucose and insulin levels in the TNK-treated groups decreased after 6 weeks of treatment. Furthermore, TNK-treated rats exhibited obvious improvements in glucose intolerance and insulin resistance. The improved glucose metabolism may be caused by the substantial reduction in serum lipids and body weight observed in SHR/cp rats starting at 3 weeks of TNK treatment. The mRNA expression of NAD+-dependent deacetylase sirtuin 1 (SIRT1) and genes related to fatty acid oxidation was markedly up-regulated in the muscle, liver and adipose tissue after TNK treatment. Furthermore, TNK promoted the deacetylation of two well-established SIRT1 targets, PPARγ coactivator 1α (PGC1α) and forkhead transcription factor 1 (FOXO1), and induced the phosphorylation of AMP-activated protein kinase (AMPK) and acetyl-CoA carboxylase (ACC) in different tissues. These observations suggested that TNK may be an alternative treatment for pre-diabetes and metabolic syndrome by inducing a gene expression switch toward fat oxidation through the activation of SIRT1 and AMPK signaling.
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Diabetes Mellitus/tratamiento farmacológico , Medicamentos Herbarios Chinos/administración & dosificación , Ácidos Grasos no Esterificados/sangre , Síndrome Metabólico/tratamiento farmacológico , Triglicéridos/sangre , Proteínas Quinasas Activadas por AMP/sangre , Animales , Peso Corporal , Diabetes Mellitus/sangre , Diabetes Mellitus/patología , Metabolismo Energético/efectos de los fármacos , Regulación de la Expresión Génica/efectos de los fármacos , Glucosa/metabolismo , Humanos , Insulina/sangre , Síndrome Metabólico/sangre , Síndrome Metabólico/patología , Ratas , Sirtuina 1/sangreRESUMEN
BACKGROUND: Chinese medicine comprised of all natural herbs is widespread used in the treatment of diabetic nephropathy (DN). Podocyte contributes to the integrity of glomerular filtration barrier whose injury plays an important role in the initiation and progression of DN. Our study aimed to investigate the effect of Qiwei granules on podocyte lesion in diabetic KK-A(y) mice kidney and its underlying mechanism. METHODS: Twelve-week-old male KK-A(y) mice were randomly divided in vehicle group and Qiwei granules group, while C57BL/6J mice were used as normal control. The mice were gavage with 1.37 g/kg/day Qiwei granules or water for 10 weeks. We measured water, food intake and body weight (BW) and fasting blood glucose (FBG) every 2 weeks, and urine protein every 4 weeks. At the end of the experiment, all surviving mice were sacrificed. The kidney weight and serum renal parameters were measured, and the renal morphology was observed. To search the underlying mechanism, we examined the podocyte positive marker, slit diaphragm protein expression and some involved cell signal pathway. RESULTS: Qiwei granules treatment significantly improved the metabolic parameters, alleviated the urinary protein, and protected renal function in KK-A(y) mice. In addition, the glomerular injuries and podocyte lesions were mitigated with Qiwei granules treatment. Furthermore, Qiwei granules increased expression of nephrin, CD2AP, and integrin alpha3beta1 in the podocytes of KK-A(y) mice. Qiwei granules improved the phosphoration of Akt and inhibited cleaved caspase-3 protein expression. CONCLUSION: These finding suggest that Qiwei granules protects the podocyte from the development of DN via improving slit diaphragm (SD) molecules expression and likely activating Akt signaling pathway in KK-A(y) mice.
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Nefropatías Diabéticas/tratamiento farmacológico , Medicamentos Herbarios Chinos/uso terapéutico , Riñón/efectos de los fármacos , Magnoliopsida , Fitoterapia , Podocitos/efectos de los fármacos , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Animales , Biomarcadores/metabolismo , Peso Corporal , Caspasa 3/metabolismo , Proteínas del Citoesqueleto/metabolismo , Nefropatías Diabéticas/metabolismo , Nefropatías Diabéticas/patología , Medicamentos Herbarios Chinos/farmacología , Integrina alfa3beta1/metabolismo , Riñón/metabolismo , Riñón/patología , Masculino , Proteínas de la Membrana/metabolismo , Ratones , Ratones Endogámicos C57BL , Podocitos/patología , Sustancias Protectoras/farmacología , Transducción de Señal/efectos de los fármacosRESUMEN
OBJECTIVE: To investigate the synergism inhibition of curcumin combined with cisplatin on T24 bladder carcinoma cells and the down-regulating effect of curcumin on the Keapl-Nrf2 pathway, a well recognized anti-drug pathway in almost drugged tumor cells. METHODS: T24 cells were cultured and treated with increasing concentrations of curcumin(5 ,10 and 20 µmol/mL) combined with cisplatin(30 µg/mL) for 24 hours. The inhibitory effects on T24 cells were tested with MTI colorimetric assay. Nuclear Nrf2 and Keapl , cytoplasmic Keapl and two typical phase II enzymes (GSTP1 and NQOl) were checked with Western blotting. RESULTS: The proliferation of T24 cells was significantly inhibited by different concentrations of curcumin combined with cisplatin. After the treatment with different concentrations of curcumin, Nuclear Nrf2 was decreased but Keapl was increased, and GSTP1 and NQO1 were decreased. CONCLUSION: Synergism inhibition of curcumin combined with cisplatin on T24 bladder carcinoma cells is observed in this research. The Keapl-Nrf2 pathway in T24 cells is down-regulated by curcumin. The expression of typical phase I enzymes (GSTP1 and NQO1) mediated by Nrf2 are decreased by curcumin. The sensitivity of tumor cells to chemotherapeutic drugs is then enhanced. These may be the mechanism of synergism effect of curcumin combined with cisplatin.