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1.
Ying Yong Sheng Tai Xue Bao ; 30(7): 2156-2164, 2019 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-31418217

RESUMO

A three-factor experiment with air temperature manipulation, soil temperature manipulation and nutrients distribution pattern was conducted in Forest Ecosystem and Global Change Research Station of Fujian Normal University in Chenda, Sanming, Fujian Province. We examined the effects of heterogeneous distribution of soil resources and warming on underground and aboveground growth of Chinese fir (Cunninghamia lanceolata) seedlings, and whether warming could change the recognition of fine roots to the heterogeneous distribution of soil resources, to understand the response of Chinese fir seedlings to heterogeneous distribution of soil resources under the background of global warming. The results showed that the recognition degree of Chinese fir to the nutrients distribution pattern was mainly reflected by the absorbing root (0-1 mm diameter class) rather than by the 1-2 mm diameter class fine roots. There were no significant effects of warming on the ratio of fine root biomass between nutrient-poor and nutrient-rich patches, the coefficient of nutrients-avoidance and the coefficient of nutrients-preference of fine roots of young Chinese fir except for the single air warming. Chinese fir had higher fine root biomass (0-1 mm diameter class) and lower height in the heterogeneous soil resource environment. Air warming decreased the biomass of fine roots (both 0-1 and 0-2 mm diameter classes) and increased the height of trees. Soil warming decreased the fine root biomass of 1-2 mm diameter class and increased the height of trees and the length of lateral branches. There was no significant interactive effect of air warming, soil warming and heterogeneity of soil resource on aboveground and belowground growth of Chinese fir. The results demonstrated that the absorbing roots of Chinese fir seedlings could recognize the heterogeneous distribution of soil resources,which was not altered by warming.


Assuntos
Cunninghamia , Biomassa , Raízes de Plantas , Plântula , Solo , Árvores
2.
Am J Physiol Renal Physiol ; 317(7): F12-F22, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31042059

RESUMO

Metabolic syndrome (MetS) is associated with nutrient surplus and kidney hyperfiltration, accelerating chronic renal failure. The potential involvement of podocyte damage in early MetS remains unclear. Mitochondrial dysfunction is an important determinant of renal damage, but whether it contributes to MetS-related podocyte injury remains unknown. Domestic pigs were studied after 16 wk of diet-induced MetS, MetS treated with the mitochondria-targeted peptide elamipretide (ELAM; 0.1 mg·kg-1·day-1 sc) for the last month of diet, and lean controls (n = 6 pigs/group). Glomerular filtration rate (GFR) and renal blood flow (RBF) were measured using multidetector computed tomography, and podocyte and mitochondrial injury were measured by light and electron microscopy. Urinary levels of podocyte-derived extracellular vesicles (pEVs; nephrin positive/podocalyxin positive) were characterized by flow cytometry. Body weight, blood pressure, RBF, and GFR were elevated in MetS. Glomerular size and glomerular injury score were also elevated in MetS and decreased after ELAM treatment. Evidence of podocyte injury, impaired podocyte mitochondria, and foot process width were all increased in MetS but restored with ELAM. The urinary concentration of pEVs was elevated in MetS pigs and directly correlated with renal dysfunction, glomerular injury, and fibrosis and inversely correlated with glomerular nephrin expression. Additionally, pEV numbers were elevated in the urine of obese compared with lean human patients. Early MetS induces podocyte injury and mitochondrial damage, which can be blunted by mitoprotection. Urinary pEVs reflecting podocyte injury might represent early markers of MetS-related kidney disease and a novel therapeutic target.

3.
Ying Yong Sheng Tai Xue Bao ; 29(11): 3569-3576, 2018 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-30460803

RESUMO

This study was carried out to analyze the changes of growth, the contents of carbohydrates and soluble protein of Zoysia japonica clonal ramets under nutrient heterogeneity, where the connected and disconnected ramets were treated with different nutrient levels. The results indicated that under the nutrient heterogeneity the parent ramets in middle or high nutrient levels improved the aboveground biomass, belowground biomass, and total biomass, with the enhancement of 32.5%, 22.1% and 24.8% at high nutrient level, respectively, reduced the root/shoot ratio, the contents of soluble sugar and non-structural carbohydrates (NSC), with the reduction of 7.7%, 15.2% and 13.1% in high nutrient level, respectively, but had no significant impacts on the contents of starch, cellulous, and soluble protein of the connected daughter ramets. The daughter ramets in middle and high nutrient levels had no significant impacts on the growth and the contents of carbohydrates and soluble protein of the connected parent ramets. There was a significant physiological integration effects from parent to the daughter ramets on the biomass, root/shoot, the contents of soluble sugar and NSC. The intensity of physiological integration was proportional to the nutrient gradient of ramets, but had no significant physiological integration effects on the contents of starch, cellulous and soluble protein. The daughter ramets had no physiological integration for any indicator of the parent ramets. There was a unidirectional physiological integration between parent and daughter ramets of Z. japonica.

4.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 36(5): 493-497, 2018 Oct 01.
Artigo em Chinês | MEDLINE | ID: mdl-30465341

RESUMO

OBJECTIVE: This study aimed to evaluate the clinical effect of pulp-less molars with defects of different degrees repaired by cast ceramic onlays of three marginal types. METHODS: A total of 165 endodontically treated molars of 105 patients were included in this study and were divided into three kinds of defect (mild, moderate, severe) according to the number of remaining axial walls. Each defect was divided into three groups according to the shape of edge to edge, bevel edge, and concave shoulder. After tooth preparation, the casting of ceramic onlays was performed. Treatment follow-up was done for the evaluation of the success and survival rates of three groups under the same defect. RESULTS: The average follow-up was 925.44 days. Under the mild defect, the success and survival rates of the edge to edge onlays were respectively 100% and 100%; bevel edge onlays, 100% and 100%; and concave shoulder onlays, 94.4% and 100%. Under the moderate defect, the success and survival rates of the edge to edge onlays were respectively 96.0% and 100%; bevel edge onlays, 80.0% and 93.3%; and concave shoulder onlays, 95.2% and 95.2%. Under the severe defect, the success and survival rates of the edge to edge onlays were respectively 95.2% and 100%; bevel edge onlays, 73.7% and 89.5%; and concave shoulder onlays, 73.3% and 80.0%. Under different defects, the success or survival rates of the three kinds of onlays had no significant difference (P>0.05). CONCLUSIONS: The edge to edge type is the most preferable way of onlay tooth preparation and can achieve good clinical results in the mild, middle, and severe tooth defection with root canal treatment.

5.
J Chem Inf Model ; 58(8): 1662-1668, 2018 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-30044626

RESUMO

Molecular docking, which mainly includes pose prediction and binding affinity calculation, has become an important tool for assisting structure-based drug design. Correctly predicting the ligand binding pose to a protein target enables the estimation of binding free energy using various tools. Previous studies have shown that the consensus method can be used to improve the docking performance with respect to compound scoring and pose prediction. In this report, a novel consensus docking strategy was proposed, which uses a dynamic benchmark data set selection to determine the best program combinations to improve the docking success rate. Using the complexes from PDBbind as a benchmark data set, a 4.9% enhancement in success rate was achieved compared with the best program.

6.
Ying Yong Sheng Tai Xue Bao ; 29(3): 811-817, 2018 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-29722223

RESUMO

This study was carried out to analyze the changes of growth and photosynthesis of clonal ramets under nutrient heterogeneity, where the connected and disconnected ramets were treated with different nutrient levels. The results showed that under the nutrient heterogeneity the parent ramets in middle or high nutrient levels improved leaf length, leaf width, root mass, leaf mass, net photosynthetic rate, stomatal conductance, transpiration rate and water use efficiency of the connected daughter ramets, with an increase of 16.0%, 8.3%, 24.4%, 58.1%, 30.3%, 54.0%, 9.2% and 21.9% in high nutrient level, respectively, but reduced the root/shoot and intercellular CO2 concentration of the connected daughter ramets, with a decreases of 21.6% and 31.5% in high nutrient level, respectively. In contrast, the daughter ramets in the middle or high nutrient level had no significant impacts on the growth and photosynthesis of the connected parent ramets. There was a physiological integration from the parent ramets to the daughter ramets. The larger the nutrient differences of ramets was, the stronger the intensity of physiological integration was. The daughter ramets were the unidirectional beneficiary from the physiological integration, as the daughter ramets benefited from the parent ramets but had no positive effects on the daughter ramets.


Assuntos
Fotossíntese , Poaceae/fisiologia , Folhas de Planta , Água
7.
Sci Rep ; 8(1): 3680, 2018 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-29487404

RESUMO

Tibial dyschondroplasia (TD) is the most-prevalent leg disorder in fast-growing chickens; it is intractable and characterized by abnormal endochondral bone formation of proximal tibial growth-plates (TGPs). Previous studies have shown that bone is a highly vascularized tissue dependent on the coordinated coupling between angiogenesis and osteogenesis, but the underlying mechanisms of bone formation and bone remodeling are poorly defined in TD chickens. Here, we observed that inhibition of vasculogenesis and angiogenesis remarkably impaired vascular invasion in the hypertrophic chondrocyte zone of the TGPs, resulting in the massive death of chondrocytes due to a shortage of blood vessels and nutrients. Moreover, the balance of the OPG (osteoprotegerin)/RANKL (receptor activator of nuclear factor-kB ligand) system is also severely disrupted during the osteogenesis process while coupling with angiogenesis, both of which eventually lead to abnormal endochondral bone formation in TD chickens. Thus, the process of vascular formation in endochondral bone appears to initiate the pathological changes in TD, and improvement of this process during coupling with osteogenesis may be a potential therapeutic approach to treat this intractable disease.

8.
Sci Rep ; 8(1): 3148, 2018 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-29453378

RESUMO

Whether plants are able to adapt to environmental changes depends on their genetic characteristics and phenotypic plastic responses. We investigated the phenotypic responses of 7 populations of an important dominant species in semi-arid steppe of China - Stipa grandis, and then distinguished which adaptive mechanism(s), phenotypic plasticity or local adaptation, was/were involved in this species to adapt to environmental changes. (1) All traits were significantly influenced by the interaction of population and growth condition and by population in each condition, and inter-population variability (CVinter) was larger in the field than in the common garden for 8/9 traits, indicating that both phenotypic plasticity and genetic differentiation controlled the phenotypic differences of S. grandis. (2) From a functional standpoint, the significant relationships between the values of traits in the common garden and the environmental variables in their original habitats couldn't support local habitat adaptation of these traits. (3) Low CVintra, low quantitative differentiation among populations (Q ST ), and low plasticity shown in the western populations indicated the very low adaptive potential of S. grandis to environmental changes. (4) From the original habitats to the common garden which is far away from S. grandis distribution region, positive phenotypic responses were found in several populations, indicating that some original habitats have become unfavorable for S. grandis.

9.
Food Funct ; 9(1): 371-378, 2018 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-29214257

RESUMO

Aging is a complex process that is accompanied by neurological damage. Chronic injection of d-galactose (d-gal) can accelerate the aging process similar to natural aging and is commonly used to build an aging model to investigate aging. In the present study, the effects of piceatannol on d-gal-induced aging in mice were evaluated. Piceatannol treatment showed an observable anti-aging effect. Results obtained in vivo showed that piceatannol retained spontaneous motor activity and enhanced spatial learning and memory abilities in mice in which aging was induced by d-gal. Morphometric analysis displayed that piceatannol prevented d-gal-induced neuronal loss, increased the number of Nissl bodies, and promoted cell proliferation in the hippocampus and cortex. Piceatannol also significantly decreased the level of MDA and elevated SOD and CAT activity in the hippocampal and cortical tissues. Furthermore, western blotting results revealed that piceatannol treatment noticeably reversed the suppression of Nrf2 nuclear translocation and increased the expressions of HO-1 and NOQ1 in mice with aging induced by d-gal. Furthermore, piceatannol activated the Nrf2 pathway in natural aging mice, whereas treatment with the Nrf2 inhibitor brusatol reversed the increased expressions of Nrf2, HO-1, and NOQ1. In conclusion, treatment with piceatannol ameliorates behavioral disorder and brain injury in an aging mouse model; this suggests that piceatannol is a promising pharmaceutical candidate for the treatment of age-associated diseases.


Assuntos
Envelhecimento/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/metabolismo , Doenças do Sistema Nervoso/tratamento farmacológico , Fármacos Neuroprotetores/administração & dosagem , Envelhecimento/metabolismo , Animais , Modelos Animais de Doenças , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Humanos , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Memória/efeitos dos fármacos , Camundongos , Fator 2 Relacionado a NF-E2/genética , Doenças do Sistema Nervoso/genética , Doenças do Sistema Nervoso/metabolismo , Doenças do Sistema Nervoso/psicologia , Estresse Oxidativo/efeitos dos fármacos , Estilbenos
10.
Antioxid Redox Signal ; 28(14): 1323-1337, 2018 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-28874056

RESUMO

AIMS: Ceruloplasmin (CP), a ferrous oxidase enzyme, plays an important role in regulating iron metabolism and redox reactions. Previous studies showed that CP deficiency contributes to Parkinson's disease by increasing iron accumulation and oxidative stress in the substantia nigra. However, the role of CP in Alzheimer's disease (AD) is unclear. We hypothesized that the lack of CP gene expression would affect the pathogenesis and damage of AD by promoting abnormal iron levels and oxidative stress. RESULTS: AD mouse models were induced in CP knockout mouse either by injection of Aß25-35 into the lateral ventricle of the brain or transgenic APP expression. CP levels were decreased significantly in the hippocampus of AD patients, as well as Aß-CP+/+ and APP-CP+/+ mice. Compared to control AD mice, CP gene deletion increased memory impairment and iron accumulation, which could be associated with elevated reactive oxygen species (ROS) levels and lead to cell apoptosis mediated through the Bcl-2/Bax and Erk/p38 signaling pathways in Aß-CP-/- and APP-CP-/- mice. In contrast, the restoration of CP expression to CP-/- mice through injection of an exogenous expression plasmid into the brain ventricle alleviated Aß-induced neuronal damage in the hippocampus. INNOVATION: CP alterations in iron contents were mediated through DMT1(-IRE) and changes in ROS levels, which in turn attenuated the progression of AD through the Erk/p38 and Bcl-2/Bax signaling pathways. CONCLUSION: Our results show a protective role of CP in AD and suggest that regulating CP expression in the hippocampus may provide a new neuroprotective strategy for AD. Antioxid. Redox Signal. 28, 1323-1337.

11.
Sci Rep ; 7(1): 9089, 2017 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-28831181

RESUMO

Tibial dyschondroplasia (TD) is an intractable poultry problem that is characterized by the appearance of non-vascularized and non-mineralized cartilage masses in tibial growth plates (TGPs). However, the role of angiogenesis inhibition in the occurrence of TD remains unknown. In this study, we found that, compared to low-altitude Arbor Acres chickens (AACs), high-altitude Tibetan chickens showed higher tibial vascular distributions that were accompanied by up-regulation of hypoxia-inducible factor-1α (HIF-1α), vascular endothelial growth factor A (VEGFA) and VEGF receptors. These observations provide insights into hypoxia-induced angiogenesis, which may be related to the absence of TD in high-altitude native Tibetan chickens. Importantly, hypoxia experiments also showed that during hypoxia, tibial angiogenesis was enhanced, which was due to pro-angiogenic factor up-regulation (including VEGFA, VEGFR1, VEGFR2, and IL-8), in AACs. Moreover, we observed that thiram-induced TD could strongly inhibit tibial angiogenesis in the hypertrophic zone through coordinated down-regulation of HIF-1α and pro-angiogenic factors, leading to a disruption in the blood supply to the TGP. Taken together, these findings reveal that the occurrence of TD is highly associated with inhibition of tibial angiogenesis through down-regulated expression of HIF-1α, VEGFA and VEGF receptors, which results in suppression of TGP development.

12.
Molecules ; 22(7)2017 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-28753960

RESUMO

A new triterpene glycoside ilexdunnoside A (1) and a new sulfated triterpene derivative ilexdunnoside B (2), together with five known analogues 3-7 were isolated from the roots of Ilex dunniana Levl. The structures were established by NMR spectroscopic analysis and acid hydrolysis. Results of an in vivo study of the biological activity showed that 75% ethanol and n-butanol extracts of the plant displayed anti-inflammatory activities against ear edema in mice, with inhibition rates of 23.5% and 37.5%, respectively, at a dose of 50 mg/kg. Furthermore, Compounds 1, 2 and 3 exhibited moderate indirect inhibitory effects on lipopolysaccharide-induced NO production in BV2 microglial cells in vitro, with IC50 values of 11.60, 12.30 and 9.70 µM, respectively.


Assuntos
Anti-Inflamatórios/farmacologia , Glicosídeos/farmacologia , Ilex/química , Inflamação/tratamento farmacológico , Raízes de Plantas/química , Triterpenos/farmacologia , Animais , Anti-Inflamatórios/química , Linhagem Celular , Edema/tratamento farmacológico , Glicosídeos/química , Camundongos , Triterpenos/química
13.
Rejuvenation Res ; 20(6): 462-472, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28622086

RESUMO

In this study, we evaluated the protective effects of naringenin on aging mice induced by d-galactose (d-gal). Open field test and Morris water maze test were performed to evaluate the effect of naringenin on behavioral dysfunction. Hematoxylin-eosin staining, TUNEL staining, and Nissl staining were used to estimate the effect of naringenin on neurological deficits. Furthermore, naringenin markedly activated PI3K/Akt signaling, eventually promoted the nuclear translocation of nuclear factor-erythroid 2-related factor 2, and induced the expression of heme oxygenase 1 and NAD(P)H-quinone oxidoreductase 1. Superoxide dismutase (SOD), catalase (CAT), and thiobarbituric acid reactive substances (TBARS) assays were conducted to evaluate oxidative stress in d-gal-induced aging mice. Our finding demonstrated that naringenin was a promising agent for attenuating the aging process, and enhancing endogenous antioxidant defense capacity was a reliable strategy to delay the senescence process.


Assuntos
Envelhecimento/patologia , Comportamento Animal , Encéfalo/fisiopatologia , Flavanonas/farmacologia , Fator 2 Relacionado a NF-E2/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Apoptose/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Encéfalo/patologia , Modelos Animais de Doenças , Flavanonas/química , Galactose , Masculino , Memória/efeitos dos fármacos , Camundongos Endogâmicos ICR , Atividade Motora/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Tamanho do Órgão/efeitos dos fármacos , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Aprendizagem Espacial/efeitos dos fármacos
14.
J Asian Nat Prod Res ; 19(2): 188-193, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28252343

RESUMO

Phytochemistry investigation on Pteris ensiformis led to the isolation of a new ent-kaurane diterpenoid, ent-kaurane-6ß,16α-diol-3-one (1), along with five known diterpenoids (2-6) and three known sesquiterpenes (7-9). Their structures were established by means of spectroscopic methods. The ethanol extract and the isolated compounds (1-9) were evaluated for their antitumor activity against three cancer cell lines.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Diterpenos de Caurano/isolamento & purificação , Diterpenos de Caurano/farmacologia , Pteris/química , Antineoplásicos Fitogênicos/química , Diterpenos/química , Diterpenos/isolamento & purificação , Diterpenos/farmacologia , Diterpenos de Caurano/química , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular
16.
Medicine (Baltimore) ; 95(33): e4548, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27537579

RESUMO

The purpose of this study was to explore the effect of lower limb rehabilitation gymnastics on postoperative rehabilitation in elderly patients with femoral shaft fracture after undergoing intramedullary nail fixation surgery.We collected medical records of elderly patients aged ≥ 60 years with femoral shaft fracture between 03/2010 and 03/2015 in Longyao County Hospital. Totally, 160 patients were identified and divided into the intervention group (n = 80) and the control group (n = 80). During the postoperative period, the intervention group received lower limb rehabilitation gymnastics treatment for 3 months, but the control group did not. All patients were routinely asked to return hospital for a check in the 1st postoperative week, as well as the 2nd week, the 1st month, and the 3rd month, after surgery. The clinical rehabilitation effect was evaluated by checking lower limb action ability, detecting the lower limb deep venous thrombosis (DVT), scoring muscle strength of quadriceps and visual analog scale (VAS) score, and performing satisfaction survey.At the 1st week and 2nd week after surgery, the clinical rehabilitation effect in the intervention group was better regarding lower limb action ability, lower limb DVT, muscle strength of quadriceps, VAS score, and patient satisfaction, as compared with the control group. However, there was no significant difference at the 1st month and the 3rd month after surgery when comparing the intervention group to the control group.In the early postoperative stage, lower limb rehabilitation gymnastics can effectively improve the recovery of lower limb function, beneficial to reducing postoperative complications such as lower limb DVT and muscle atrophy, and increasing patient satisfaction rate.


Assuntos
Fraturas do Fêmur/reabilitação , Fixação Intramedular de Fraturas/reabilitação , Ginástica , Idoso , Estudos de Casos e Controles , Fraturas do Fêmur/cirurgia , Ginástica/fisiologia , Humanos , Perna (Membro)/fisiologia , Masculino , Força Muscular/fisiologia , Satisfação do Paciente , Estudos Retrospectivos , Trombose Venosa/prevenção & controle
17.
Environ Sci Pollut Res Int ; 23(13): 13531-42, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27030239

RESUMO

Perfluorooctanoic acid (PFOA) is extremely persistent and bioaccumulative in the environment; thus, it is very urgent to investigate an effective and moderate technology to treat the pollution of PFOA. In this study, a process combined iron and granular activated carbon (Fe(0)/GAC) micro-electrolysis with VUV-Fenton system is employed for the remediation of PFOA. Approximately 50 % PFOA (10 mg L(-1)) could be efficiently defluorinated under the following conditions: pH 3.0, dosage of Fe 7.5 g L(-1), dosage of GAC 12.5 g L(-1), and concentration of H2O2 22.8 mmol L(-1). Meanwhile, during the process, evident defluorination was observed and the concentration of fluoride ion was eventually 3.23 mg L(-1). The intermediates including five shorter-chain perfluorinated carboxylic acids (PFCAs), i.e., C7, C6, C5, C4, and C3, were also analyzed by high-performance liquid chromatography tandem mass spectrometry (HPLC/MS/MS) and defluorination mechanisms of PFOA was proposed, which involved photochemical of OH·, direct photolysis (185-nm VUV), and photocatalytic degradation of PFOA in the presence of Fe(3+) (254-nm UV).


Assuntos
Caprilatos/química , Caprilatos/efeitos da radiação , Eletrólise/métodos , Fluorcarbonetos/química , Fluorcarbonetos/efeitos da radiação , Peróxido de Hidrogênio/química , Fotólise , Carbono/análise , Carbono/metabolismo
18.
Phys Chem Chem Phys ; 18(4): 3080-5, 2016 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-26742089

RESUMO

Using first-principles calculations, we investigate the strain effects on the charge density wave states of monolayer and bilayer 1T-TaS2. The modified stability of the charge density wave in the monolayer is understood in terms of the strain dependent electron localization, which determines the distortion amplitude. On the other hand, in the bilayer, the effect of strain on the interlayer interaction is also crucial. The rich phase diagram under strain opens new venues for applications of 1T-TaS2. We interpret the experimentally observed insulating state of bulk 1T-TaS2 as inherited from the monolayer by effective interlayer decoupling.

19.
Chin J Nat Med ; 14(10): 757-768, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28236405

RESUMO

Herpetospermum caudigerum lignans (HTL), one of the potential drugs with anti-hepatitis B virus and hepatoprotective effects, has limited clinical applications because of poor aqueous solubility and low bioavailability. Both herpetrione (HPE) and herpetin (HPN) are the most abundant ingredients in HTL and exhibit weak acidity. The purpose of the present study was to produce dried preparations of HTL (composed of HPE and HPN) nanosuspensions (HTL-NS) with high redispersibility using lyophilization technology. The HTL-NS was prepared by utilizing precipitation-combined homogenization technology based on acid-base neutralization reactions, and critical formulation and process parameters affecting the characteristics of HTL-NS were optimized. The resultant products were characterized by particle size analysis, SEM, XRD, stability, solubility, dissolution and in vivo bioavailability. HTL-NS showed near-spherical-shaped morphology and the size was 243 nm with a narrow PDI value of 0.187. The dried preparations with a relatively large particle size of 286 nm and a PDI of 0.215 were achieved by using 4% (W/V) mannitol as cryoprotectants, and had a better stability at 4 or 25 °C for 2 months, compared to HTL-NS. In the in vitro test, the dried preparations showed markedly increased solubility and dissolution velocity. Besides, in the in vivo evaluation, it exhibited significant increases in AUC0-t, Cmax,MRT and a decrease in Tmax, compared to the raw drug. In conclusion, our results provide a basis for the development of a drug delivery system for poorly water-soluble ingredients with pH-dependent solubility.


Assuntos
Química Farmacêutica/métodos , Lignanas/química , Lignanas/farmacocinética , Nanopartículas/química , Animais , Disponibilidade Biológica , Linhagem Celular , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Humanos , Lignanas/administração & dosagem , Masculino , Nanopartículas/administração & dosagem , Tamanho da Partícula , Ratos , Ratos Wistar , Solubilidade , Difração de Raios X
20.
J Child Neurol ; 31(3): 271-6, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26071373

RESUMO

The purpose of the present study was to investigate the possible association between temporal lobe epilepsy and NRG1 gene polymorphisms. A total of 73 patients and 69 controls were involved in this study. Genomic DNAs from the patients and controls were genotyped by polymerase chain reaction-ligase detection reaction method. There was an association of rs35753505 (T>C) with temporal lobe epilepsy (χ(2) = 6.730, P = .035). The frequency of risk allele C of rs35753505 was significantly higher (69.9%) in patients compared to controls (55.8%) (χ(2) = 6.023, P = .014). Interestingly, the significant difference of NRG1 genotype and allele frequency only existed among males, but not females. In addition, no statistically significant association was found between rs6994992, rs62510682 polymorphisms, and temporal lobe epilepsy. These data indicate that rs35753505 of NRG1 plays an important role in conferring susceptibility to the temporal lobe epilepsy in a Chinese Han population.


Assuntos
Epilepsia do Lobo Temporal/genética , Predisposição Genética para Doença , Neuregulina-1/genética , Polimorfismo de Nucleotídeo Único , Grupo com Ancestrais do Continente Asiático/genética , Criança , China , Feminino , Frequência do Gene , Estudos de Associação Genética , Técnicas de Genotipagem , Humanos , Masculino , Reação em Cadeia da Polimerase , Caracteres Sexuais
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