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1.
Eur Rev Med Pharmacol Sci ; 26(21): 7797-7812, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36394728

RESUMO

OBJECTIVE: Obesity is characterized by excess fat accumulation and closely associated with insulin resistance and type 2 diabetes. We aimed at exploring the potential effect and mechanism of escin for the treatment of obesity using network pharmacology, and to verify the effect of escin on obese mice. MATERIALS AND METHODS: Escin targets were predicted by DrugBank and SwissTarget database. Potential targets for the treatment of obesity were identified based on the DisGeNET database. Comparative analysis was used to investigate the overlapping genes between escin targets and obesity treatment-related targets. Using STRING database and Cytoscape to analyze interactions among overlapping genes, hub genes were identified. Gene Ontology (GO) function and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis were conducted in DAVID. High-fat diet (HFD) -induced obese mice were used to observe the anti-obesity effects of escin. The body weight, relevant biochemical markers and HE staining of fat and liver tissues were determined after escin was administered for 18 weeks. RESULTS: We screened 53 overlapping genes for escin and obesity. The mechanism of intervention of escin in treating obesity may involve 10 hub targets (STAT3, MTOR, NR3C1, IKBKB, PTGS2, MMP9, PRKCA, PRKCD, AR, CYP3A4). The screening and enrichment analysis revealed that the treatment of obesity using escin primarily involved 10 GO enriched terms and 13 related pathways. In vivo, escin can reduce the body weight of obese mice induced by HFD and improve lipid metabolism through lowering triglycerides (TG), total cholesterol (TC), and density lipoprotein (LDL) levels and increasing high density lipoprotein (HDL) levels and decreasing leptin level and increasing adiponectin (ADPN) level. Escin can regulate glucose metabolism caused by obesity through decreasing fasting glucose, postprandial blood glucose and regulating the level of insulin. These obese mice induced by HFD displayed the increased insulin resistance that was associated with the increased inflammatory cytokines, including interleukin 6 (IL-6), tumor necrosis factor α (TNF-α), and monocyte chemoattractant protein-1 (MCP-1). Escin may antagonize the increase of MCP-1 and partially antagonize the low-grade inflammation caused by obesity. From the morphological changes of fat and liver tissues stained by HE stain, escin could decrease the size of adipocytes and improve liver necrosis and fatty degeneration in obese mice fed by HFD. CONCLUSIONS: The network pharmacology of escin in treating obesity may involve 10 hub targets (STAT3, MTOR, NR3C1, IKBKB, PTGS2, MMP9, PRKCA, PRKCD, AR, CYP3A4), 10 GO enriched terms and 13 related pathways. In vivo, escin can be potentially used to prevent or treat obesity through reducing the weight, improving glucose and lipid metabolism, partially antagonizing the low-grade inflammation, and improved insulin resistance.


Assuntos
Diabetes Mellitus Tipo 2 , Resistência à Insulina , Animais , Camundongos , Ciclo-Oxigenase 2 , Citocromo P-450 CYP3A/uso terapêutico , Diabetes Mellitus Tipo 2/complicações , Dieta Hiperlipídica , Escina/uso terapêutico , Glucose/metabolismo , Quinase I-kappa B , Inflamação/metabolismo , Metaloproteinase 9 da Matriz , Camundongos Obesos , Obesidade , Serina-Treonina Quinases TOR
2.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 33(4): 346-352, 2021 Aug 19.
Artigo em Chinês | MEDLINE | ID: mdl-34505440

RESUMO

OBJECTIVE: To investigate the population dynamics and Echinococcus infections in small rodents around human settlement in Yushu City, Qinghai Province. METHODS: Rodents were captured using the mouse trap method in pastures from Batang Township and Longbao Township of Yushu City, Qinghai Province on May, August and October, 2018. The body weight and snout-vent length of all captured rodents were measured, and the species was identified according to the rodent morphology. Genomic DNA was extracted from rodent liver specimens and lesion specimens, and the mitochondrial cox1 gene of Echinococcus was amplified using PCR assay for identification of parasite species. In addition, the tissue specimens positive for PCR assay were sampled for pathological examinations. The prevalence of Echinococcus infections was estimated in rodents, and a phylogenetic tree was created based on Echinococcus cox1 gene sequences. RESULTS: A total of 285 small rodents were captured, including 143 Ochotona curzoniae (50.2%), 141 Lasiopodomys fuscus (49.5%), and 1 Neodon irene (0.3%), and there was a remarkable variation in habitat selection among these three rodent species. The number of L. fuscus correlated positively with vegetation coverage (r = 0.350, P = 0.264), with the greatest number seen in August, and the number of O. curzoniae negatively with vegetation coverage (r = -0.371, P = 0.235), with the highest number seen in August and the lowest number in May. The female/male ratios of O. curzoniae and voles were 1:0.96 and 0.82:1, respectively. The body weight (r = 0.519, P < 0.01) and snout-vent length (r = 0.578, P < 0.01) of O. curzoniae showed a tendency towards a rise with month, while the body weight (r = -0.401, P < 0.01) and snout-vent length (r = -0.570, P < 0.01) of voles presented a tendency towards a reduction with month. No Echinococcus infection was detected in voles, while 2.1% prevalence of E. shiquicus infection was seen in O. curzoniae. Phylogenetic analysis revealed consistent sequences of cox1 gene from E. shiquicus in Yushu City of Qinghai Province and Shiqu County, Ganzi Tibetan Autonomous Prefecture of Sichuan Province. CONCLUSIONS: The small rodents around the human settlement in Yushu City of Qinghai Province mainly include O. curzoniae and L. fuscus, with the greatest numbers seen in May and August, respectively. Following the concerted efforts for echinococcosis control, the prevalence of Echinococcus infections is low in small rodents around the human settlement in Yushu City; however, there is still a risk of echinococcosis transmission.


Assuntos
Equinococose , Echinococcus , Animais , China/epidemiologia , Equinococose/epidemiologia , Echinococcus/genética , Feminino , Humanos , Masculino , Camundongos , Filogenia , Dinâmica Populacional , Roedores
3.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 32(4): 414-418, 2020 Jun 11.
Artigo em Chinês | MEDLINE | ID: mdl-32935520

RESUMO

OBJECTIVE: To analyze the advantages, disadvantages, opportunities and challenges for schistosomiasis elimination in Laos, so as to propose the corresponding healthy policies and suggestions. METHODS: A SWOT analysis was performed to analyze the strength, weakness, opportunity and threat for the schistosomiasis elimination program in Laos, and the corresponding policy suggestions were proposed. RESULTS: The national schistosomiasis elimination program of Laos receives governmental emphases and great supports. A strategy based on mass drug administration was proposed and a sentinel site-bases surveillance system has been built for schistosomiasis elimination in Laos; however, there are several challenges for the national schistosomiasis elimination program in Laos, including insufficient financial supports, inadequate professional capability, weak schistosomiasis control awareness in community populations and difficulty in vector control. CONCLUSIONS: Persistent governmental leadership, increasing financial supports, strengthening professional team building and improving schistosomiasis control awareness in community populations are required to facilitate the progress towards schistosomiasis elimination in Laos.


Assuntos
Erradicação de Doenças , Programas Nacionais de Saúde , Esquistossomose , Erradicação de Doenças/normas , Humanos , Laos , Programas Nacionais de Saúde/economia , Programas Nacionais de Saúde/normas , Controle de Pragas , Esquistossomose/prevenção & controle
4.
Eur Rev Med Pharmacol Sci ; 24(10): 5734-5741, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32495909

RESUMO

OBJECTIVE: Many parallel-group studies of migraine prophylaxis using valproate medications were reported in recent decades. This meta-analysis assessed the efficacy and safety of valproate medications for migraine prophylaxis in adults. MATERIALS AND METHODS: Searches were conducted in five databases: PubMed, Wiley, ScienceDirect, Web of Science, and the Cochrane Library. The data were acquired through December 31, 2018. Two independent authors searched for controlled clinical trials involving the use of valproate medications in migraine prophylaxis. Studies that met the inclusion criteria were assessed, and their methodological quality was examined. RESULTS: Seven placebo-controlled studies (782 participants) and seven controlled trials against active comparators (554 participants) were included in the final analysis. The active treatment of valproate medications was significantly superior to placebo (OR, 4.02; 95% CI 2.17-7.44; I2 = 66%). Compared with the other active comparators, there were no significant differences between treatments in the proportion of responders. CONCLUSIONS: Valproate medications were more effective than placebo in migraine prevention, with statistically significant differences. Both valproate and the other active comparators were well-tolerated, and no significant difference was noted in efficacy and safety for the prophylaxis of migraine.


Assuntos
Anticonvulsivantes/uso terapêutico , Transtornos de Enxaqueca/tratamento farmacológico , Ácido Valproico/uso terapêutico , Adulto , Anticonvulsivantes/efeitos adversos , Humanos , Ácido Valproico/efeitos adversos
5.
Animal ; 14(11): 2414-2422, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32423522

RESUMO

The meat quality of chicken is an important factor affecting the consumer's health. It was hypothesized that n-3 polyunsaturated fatty acid (n-3 PUFA) could be effectively deposited in chicken, by incorporating antioxidation of soybean isoflavone (SI), which led to improved quality of chicken meat for good health of human beings. Effects of partial or complete dietary substitution of lard (LA) with linseed oil (LO), with or without SI on growth performance, biochemical indicators, meat quality, fatty acid profiles, lipid-related health indicators and gene expression of breast muscle were examined in chickens. A total of 900 males were fed a corn-soybean meal diet supplemented with 4% LA, 2% LA + 2% LO and 4% LO and the latter two including 30 mg SI/kg (2% LA + 2% LO + SI and 4% LO + SI) from 29 to 66 days of age; each of the five dietary treatments included six replicates of 30 birds. Compared with the 4% LA diet, dietary 4% LO significantly increased the feed efficiency and had no negative effect on objective indices related to meat quality; LO significantly decreased plasma triglycerides and total cholesterol (TCH); abdominal fat percentage was significantly decreased in birds fed the 4% LO and 4% LO + SI diets. Chickens with LO diets resulted in higher contents of α-linolenic acid (C18:3n-3), EPA (C20:5n-3) and total n-3 PUFA, together with a lower content of palmitic acid (C16:0), lignoceric acid (C24:0), saturated fatty acids and n-6:n-3 ratio in breast muscle compared to 4% LA diet (P < 0.05); they also significantly decreased atherogenic index, thrombogenic index and increased the hypocholesterolemic to hypercholesterolemic ratio. Adding SI to the LO diets enhanced the contents of EPA and DHA (C22:6n-3), plasma total superoxide dismutase, reduced glutathione (GSH)/oxidized glutathione and muscle GSH content, while decreased plasma total triglyceride and TCH and malondialdehyde content in plasma and breast muscle compared to its absence (P < 0.05). Expression in breast muscle of fatty acid desaturase 1 (FADS1), FADS2, elongase 2 (ELOVL2) and ELOVL5 genes were significantly higher with the LO diets including SI than with the 4% LA diet. Significant interactions existed between LO level and inclusion of SI on EPA and TCH contents. These findings indicate that diet supplemented with LO combined with SI is an effective alternative when optimizing the nutritional value of chicken meat for human consumers.


Assuntos
Galinhas , Isoflavonas , Metabolismo dos Lipídeos/genética , Ração Animal/análise , Animais , Dessaturase de Ácido Graxo Delta-5 , Dieta/veterinária , Ácidos Graxos , Expressão Gênica , Óleo de Semente do Linho , Lipídeos , Carne/análise , Músculos/metabolismo , Glycine max
6.
Artigo em Chinês | MEDLINE | ID: mdl-32062891

RESUMO

Objective: To detect the prevalence of sleep disorders among metro staff and to analyze influencing effects of effort reward imbalance (ERI) on it. Methods: In January 2015, subway driver, dispatcher and station operator from Guangzhou subway were selected as the research object in the whole group sampling method. A total of 1200 questionnaires were distributed and 1124 were valid questionnaires, and the effective questionnaire recovery rate was 93.7%. Based on the effort reward imbalance questionnaire and the self-administered sleep questionnaire, the data of the general demographic characteristics, life satisfaction, occupational stress and sleep status of the respondents were collected. Epi.data3.1 and spss19.0 were used for analyzing. Results: A total of 1124 subway employees were surveyed, with an average age of (28±5) years; the working age was (4.5±3.6) years. ERI occupied 24.7% (278/1124) of the study population and sleep disorders as 42.2% (474/1124) . Single factor analysis showed that marital status, educational level, work position, life satisfaction and ERI could significantly influence sleep disorders of metro staff (P<0.05) . Logistic regression showed that higher effort (adjusted OR=2.56, 95%CI: 1.79-3.68) , lower reward (adjusted OR=1.90, 95%CI: 1.34-2.68) and ERI (adjusted OR=2.33, 95%CI: 1.69-3.22) could increase the risk of sleep disorders after the confounding factors were controlled. ERI (adjusted OR=2.89, 95% CI: 1.80-4.64) , and over commitment (adjusted OR=4.64, 95%CI: 2.81-7.68) could influence the risk of sleep disorders independently when over commitment was evaluated as a moderating variable. Conclusion: Occupational stress as ERI could influence the risk of sleep disorders among metro staff. The situation should not be neglected for occupational health of metro staff.


Assuntos
Saúde Ocupacional , Estresse Ocupacional , Recompensa , Transtornos do Sono-Vigília/epidemiologia , Adulto , China , Estudos Transversais , Humanos , Satisfação no Emprego , Inquéritos e Questionários , Adulto Jovem
7.
Animal ; 14(6): 1322-1332, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31915098

RESUMO

The fatty acid composition of chicken's meat is largely influenced by dietary lipids, which are often used as supplements to increase dietary caloric density. The underlying key metabolites and pathways influenced by dietary oils remain poorly known in chickens. The objective of this study was to explore the underlying metabolic mechanisms of how diets supplemented with mixed or a single oil with distinct fatty acid composition influence the fatty acid profile in breast muscle of Qingyuan chickens. Birds were fed a corn-soybean meal diet supplemented with either soybean oil (control, CON) or equal amounts of mixed edible oils (MEO; soybean oil : lard : fish oil : coconut oil = 1 : 1 : 0.5 : 0.5) from 1 to 120 days of age. Growth performance and fatty acid composition of muscle lipids were analysed. LC-MS was applied to investigate the effects of CON v. MEO diets on lipid-related metabolites in the muscle of chickens at day 120. Compared with the CON diet, chickens fed the MEO diet had a lower feed conversion ratio (P < 0.05), higher proportions of lauric acid (C12:0), myristic acid (C14:0), palmitoleic acid (C16:1n-7), oleic acid (C18:1n-9), EPA (C20:5n-3) and DHA (C22:6n-3), and a lower linoleic acid (C18:2n-6) content in breast muscle (P < 0.05). Muscle metabolome profiling showed that the most differentially abundant metabolites are phospholipids, including phosphatidylcholines (PC) and phosphatidylethanolamines (PE), which enriched the glycerophospholipid metabolism (P < 0.05). These key differentially abundant metabolites - PC (14:0/20:4), PC (18:1/14:1), PC (18:0/14:1), PC (18:0/18:4), PC (20:0/18:4), PE (22:0/P-16:0), PE (24:0/20:5), PE (22:2/P-18:1), PE (24:0/18:4) - were closely associated with the contents of C12:0, C14:0, DHA and C18:2n-6 in muscle lipids (P < 0.05). The content of glutathione metabolite was higher with MEO than CON diet (P < 0.05). Based on these results, it can be concluded that the diet supplemented with MEO reduced the feed conversion ratio, enriched the content of n-3 fatty acids and modified the related metabolites (including PC, PE and glutathione) in breast muscle of chickens.


Assuntos
Galinhas/fisiologia , Gorduras Insaturadas na Dieta/farmacologia , Ácidos Graxos/metabolismo , Músculo Esquelético/fisiologia , Animais , Dieta/veterinária , Gorduras Insaturadas na Dieta/administração & dosagem , Suplementos Nutricionais , Ácidos Graxos/química , Metabolismo dos Lipídeos , Metaboloma
9.
Phys Rev Lett ; 122(1): 016802, 2019 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-31012670

RESUMO

The surface of diamond is reported to undergo nonablative photochemical etching when exposed to ultraviolet (UV) radiation which allows controlled single and partial layer removal of lattice layers. Oxygen termination of surface dangling bonds is known to be crucial for the etching process; however, the exact mechanism of carbon ejection remains unclear. We investigate the interaction of UV laser pulses with oxygen-terminated diamond surfaces using atomic-scale surface characterization combined with first-principles time-dependent density functional theory calculations. We present evidence for laser-induced desorption (LID) from carbonyl functional groups at the diamond {001} surface. The doubly bonded carbonyl group is photoexcited into a triply bonded CO-like state, including scission of the underlying C─C bonds. The carbon removal process in LID is atom by atom; therefore, this mechanism provides a novel "top-down" approach for creating nanostructures on the surface of diamond and other carbon-containing semiconductors.

10.
Artigo em Chinês | MEDLINE | ID: mdl-30669195

RESUMO

The pathogenesis of allergic rhinitis (AR) has not well been clarified, and the imbalance of immune system is its important feature. Interaction between innate and adaptive immune cells and inflammatory mediators secreted by them triggers, maintains and aggravates AR. In this review, Toll-like receptor signaling pathways are used as a bridge to systematically analyze the mechanisms of innate and adaptive immunity in the development of AR.

11.
Beijing Da Xue Xue Bao Yi Xue Ban ; 50(1): 85-90, 2018 Feb 18.
Artigo em Chinês | MEDLINE | ID: mdl-29483728

RESUMO

OBJECTIVE: Three kinds of zirconia specimens were made respectively by milling of the prisintered blocks and by three dimensional (3D) gel deposition for in vitro evaluation of their optical translucency under three different thicknesses and their color masking effect on discolored teeth. The study aims for establishing the principle for guiding the materials selection in clinical practice. METHODS: Ninety A2-colored zirconia disc specimens with diameter of 14 mm were prepared and were divided into three groups (n=30). (1) Group CZ, by milling of the presintered blanks; (2) Group NZW, by 3D gel deposition, without a color masking opaque inner layer; (3) Group NZY, by 3D gel deposition, with a color masking opaque inner layer. Furthermore, each group was divided into three sub-groups (n=10) according to the sample thickness, i.e., 0.6, 1.0 and 1.5 mm, respectively. The maxillary anterior teeth with severe discoloration, extracted owing to periodontal disease, were collected and embedded. By gentle gridding and polishing a plane, larger than 6 mm2×6 mm2, was generated on the labial surface of each tooth. Chromatic values(CIE1976-L*a*b*) of the zirconia samples in the nine sub-groups were measured by the spectrophotometer Crystaleye in front of the black or white background in a cassette, and the translucency parameter (TP) values were calculated for each sample. Thereafter the zirconia specimens were bonded onto the labial surface of the polished teeth for measuring the chromatic values, using the chromatic value of the medium 1/3 of the standardized Vita A2 as a control. The color aberration ΔE between each zirconia specimen and the control value was calculated, respectively. The results were statistically analyzed by One-way ANOVA and Bonferroni. RESULTS: (1) The optical transparency of the three kinds of zirconia disc specimens with the thickness of 0.6, 1.0 and 1.5 mm was 14.09, 12.31 and 10.45 for group CZ; 19.84, 16.54 and 12.44 for group NZW;14.81, 13.16 and 11.92 for group NZY. In each group, the degree of optical transparency of the specimens showed a clear tendency as in the sub-group 0.6 mm >1.0 mm >1.5 mm. The TP value of the specimens in the three groups with the same thickness showed a tendency of the group NZW >group NZY >group CZ. (2) After bonding onto the polished labial surface of the teeth, the color aberration ΔE of the specimens with the thickness of 0.6, 1.0 and 1.5 mm was calculated to be 10.77, 9.94 and 8.50 for group CZ; 6.84, 5.89 and 5.29 for group NZW; 4.16, 3.92 and 3.67 for group NZY. In each group, the color aberration of the specimens showed a clear tendency as in the sub-group 0.6 mm >1.0 mm >1.5 mm; the color aberration of the three groups with the same thickness was in the order of the group CZ >group NZW >group NZY. CONCLUSION: In all the specimen groups with a fixed specimen thickness, the optical translucency of the specimen was the highest in group NZW made by 3D gel deposition, and the best color masking effect was obtained in specimens with a color masking opaque inner layer in group NZY, where a thickness of 0.6 mm was sufficient enough for obtaining the ideal color masking effect.


Assuntos
Cerâmica , Descoloração de Dente , Zircônio , Cor , Humanos , Teste de Materiais
12.
J Phys Chem A ; 121(47): 9058-9063, 2017 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-29111726

RESUMO

The potential of C60 as a nucleic acid base (NAB) optical sensor is theoretically explored. We investigate the adsorption of four NABs, namely, adenine, cytosine, guanine, and thymine, on C60 in the gas phase. For the optimal NAB@C60 adsorption configurations, obtained using a dispersion-corrected density functional, we calculate the vis-near-ultraviolet optical response using time-dependent density functional theory. While the isolated C60 and NAB molecules do not exhibit visible optical excitation, we find that C60/NAB conjugation gives rise to distinct spectral features in the visible range. These results suggest that C60 conjugation can be applied for photodetection of individual NABs.

13.
J Phys Chem Lett ; 8(10): 2189-2194, 2017 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-28457138

RESUMO

Density functional theory and nonequilibrium Green's function calculations have been used to explore spin-resolved transport through the high-spin state of an iron(II)sulfur single molecular magnet. Our results show that this molecule exhibits near-perfect spin filtering, where the spin-filtering efficiency is above 99%, as well as significant negative differential resistance centered at a low bias voltage. The rise in the spin-up conductivity up to the bias voltage of 0.4 V is dominated by a conductive lowest unoccupied molecular orbital, and this is accompanied by a slight increase in the magnetic moment of the Fe atom. The subsequent drop in the spin-up conductivity is because the conductive channel moves to the highest occupied molecular orbital, which has a lower conductance contribution. This is accompanied by a drop in the magnetic moment of the Fe atom. These two exceptional properties, and the fact that the onset of negative differential resistance occurs at low bias voltage, suggests the potential of the molecule in nanoelectronic and nanospintronic applications.

14.
Phys Chem Chem Phys ; 19(18): 11485-11491, 2017 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-28425542

RESUMO

Perovskite zirconates such as SrZrO3 exhibit improved proton solubility and conductivity when doped with trivalent cations substituting at the Zr site. In this work, we present a detailed study of Sc and Y dopants in SrZrO3 based on first-principles, hybrid density-functional calculations. When substituting at the Zr site (ScZr, YZr), both dopants give rise to a single, deep acceptor level, where the neutral impurity forms a localized hole polaron state. The ε(0/-) charge transition levels are 0.60 eV and 0.58 eV above the valence-band maximum for ScZr and YZr, respectively. Under certain growth conditions, Sc and Y will form self-compensating donor species by substituting at the Sr site (ScSr, YSr), and this is detrimental to proton conductivity. Due to its larger ionic radius, Y exhibits a greater tendency than Sc to self-compensate at the Sr site. We also investigated the proton-dopant association. The binding energy of a proton to a negatively charged acceptor impurity is 0.41 eV for Sc and 0.31 eV for Y, indicating that proton transport is limited by trapping at impurity sites.

16.
Phys Rev Lett ; 117(22): 227202, 2016 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-27925730

RESUMO

Here we present a study of magnetism in Co_{0.05}Ti_{0.95}O_{2-δ} anatase films grown by pulsed laser deposition under a variety of oxygen partial pressures and deposition rates. Energy-dispersive spectrometry and transmission electron microscopy analyses indicate that a high deposition rate leads to a homogeneous microstructure, while a very low rate or postannealing results in cobalt clustering. Depth resolved low-energy muon spin rotation experiments show that films grown at a low oxygen partial pressure (≈10^{-6} torr) with a uniform structure are fully magnetic, indicating intrinsic ferromagnetism. First principles calculations identify the beneficial role of low oxygen partial pressure in the realization of uniform carrier-mediated ferromagnetism. This work demonstrates that Co:TiO_{2} is an intrinsic diluted magnetic semiconductor.

17.
Zhonghua Nei Ke Za Zhi ; 55(11): 872-874, 2016 Nov 01.
Artigo em Chinês | MEDLINE | ID: mdl-27801344

RESUMO

The expression of CD107a, NKG2D on the surface of natural killer (NK) cells and serum soluble major histocompatibility complex class Ⅰ chain-related A (sMICA) level in patients with extranodal NK/T cell lymphoma, nasal type (ENKL) were detected.We found that CD107a expression was reduced on the surface of NK cells, suggesting impaired NK cell activity in ENKL patients, which may result from decreased NKG2D expression.


Assuntos
Antígenos de Histocompatibilidade Classe I/sangue , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Linfoma Extranodal de Células T-NK/imunologia , Subfamília K de Receptores Semelhantes a Lectina de Células NK/metabolismo , Neoplasias Nasais/imunologia , Antígenos de Histocompatibilidade Classe I/metabolismo , Humanos , Linfoma Extranodal de Células T-NK/sangue , Linfoma Extranodal de Células T-NK/patologia , Neoplasias Nasais/sangue , Neoplasias Nasais/patologia
18.
Phys Chem Chem Phys ; 18(31): 21315-21, 2016 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-27426253

RESUMO

Based on density-functional theory and non-equilibrium Green's function calculations, we demonstrate that endohedral metallofullerenes (EMFs) are reactive to open-shell gases, and therefore have the potential application as selective open-shell gas sensors. The adsorption of eight gas species (CO, H2O, H2S, NO2, NO, SO2, O2 and NH3) on three EMFs (M@C60, M = Ca, Na and Sr) shows that the adsorption energies of the EMFs towards NO2 and NO are significantly higher than the closed-shell species. Moreover, the high selectivity appears relatively insensitive to the inserted metal atoms. The calculated current-voltage characteristics of gold-M@C60-gold structures (M = Ca, Na) show that the adsorption of NO2 leads to significant change in conductivity, suggesting a potential application as an EMF gas resistive sensing device.

19.
Phys Chem Chem Phys ; 18(24): 16224-8, 2016 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-27252042

RESUMO

Through first-principles calculations using the nonequilibrium Green's function formalism together with density functional theory, we study the conductance of double-vacancy zigzag graphene nanoribbons doped with four transition metal atoms Ti, V, Cr and Fe. We show that Ti doping induces large spin-filtering with an efficiency in excess of 90% for bias voltages below 0.5 V, while the other metal adatoms do not induce large spin filtering. This is despite the fact that the Ti dopant possesses small spin moment, while large moments reside on V, Cr and Fe dopants. Our analysis shows that the suppression of transmission in the spin-down channel in the Ti-doped graphene nanoribbon, thus the large spin filtering efficiency, is due to transmission anti-resonance arising from destructive quantum interference. These findings suggest that the decoration of graphene with titanium, and possibly other transition metals, can act as effective spin filters for nanospintronic applications.

20.
J Chem Phys ; 144(2): 021101, 2016 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-26772547

RESUMO

Based on the nonequilibrium Green's function formalism and density-functional theory, we investigate the onset of electrical rectification in a single C59N molecule in conjunction with gold electrodes. Our calculations reveal that rectification is dependent upon the anchoring of the Au atom on C59N; when the Au electrode is singly bonded to a C atom (labeled here as A), the system does not exhibit rectification, whereas when the electrode is connected to the C-C bridge site between two hexagonal rings (labeled here as B), transmission asymmetry is observed, where the rectification ratio reaches up to 2.62 at ±1 V depending on the N doping site relative to the anchoring site. Our analysis of the transmission mechanism shows that N doping of the B configuration causes rectification because more transmission channels are available for transmission in the B configuration than in the A configuration.

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