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1.
Biomolecules ; 9(9)2019 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-31480279

RESUMO

Cold stress can induce neuroinflammation in the hippocampal dentate gyrus (DG), but the mechanism underlying neuronal apoptosis induced by cold stress is not well-understood. To address this issue, male and female C57BL/6 mice were exposed to a temperature of 4 °C for 3 h per day for 1 week, and glial cell activation, neuronal apoptosis, and neuroinflammation were evaluated by western blotting, immunofluorescence, terminal deoxynucleotidyl transferase 2'-deoxyuridine 5'-triphosphate (dUTP) nick end labeling, Nissl staining, and immunohistochemistry. Additionally, BV2 cells were treated with different concentrations of cortisol (CORT) for 3 h to mimic stress and molecular changes were assessed by western blotting, immunofluorescence, and co-immunoprecipitation. We found that excess CORT activated glial cells and increased neuroinflammation in the DG of mice exposed to cold temperatures, which was associated with increased acetylation and nuclear factor-κB signaling. These effects were mediated by the acetylation of lysine 9 of histone 3 and lysine 310 of p65, which resulted in increased mitogen-activated protein kinase phosphorylation, nuclear translocation of p65, microglia activation, and acetylation of high-mobility group box 1. Neuroinflammation was more severe in male compared to female mice. These findings provide new insight into the mechanisms of the cold stress response, which can inform the development of new strategies to combat the effects of hypothermia.

2.
Cells ; 8(6)2019 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-31216749

RESUMO

Cold stress can induce neuronal apoptosis in the hippocampus, but the internal mechanism involving neuronal loss induced by cold stress is not clear. In vivo, male and female C57BL/6 mice were exposed to 4 °C, 3 h per day for 1 week. In vitro, HT22 cells were treated with different concentrations of cortisol (CORT) for 3 h. In vivo, CORT levels in the hippocampus were measured using ELISA, western blotting, and immunohistochemistry to assess the neuronal population and oxidation of the hippocampus. In vitro, western blotting, immunofluorescence, flow cytometry, transmission electron microscopy, and other methods were used to characterize the mechanism of mitochondrial damage induced by CORT. The phenomena of excessive CORT-mediated oxidation stress and neuronal apoptosis were shown in mouse hippocampus tissue following cold exposure, involving mitochondrial oxidative stress and endogenous apoptotic pathway activation. These processes were mediated by acetylation of lysine 9 of histone 3, resulting in upregulation involving Adenosine 5'-monophosphate (AMP)-activated protein kinase (APMK) phosphorylation and translocation of Nrf2 to the nucleus. In addition, oxidation in male mice was more severe. These findings provide a new understanding of the underlying mechanisms of the cold stress response and explain the apoptosis process induced by CORT, which may influence the selection of animal models in future stress-related studies.

3.
Nat Commun ; 10(1): 1102, 2019 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-30846687

RESUMO

Nonlinear transmission lines (NLTLs) are nonlinear electronic circuits used for parametric amplification and pulse generation, and it is known that left-handed NLTLs support enhanced harmonic generation while suppressing shock wave formation. We show experimentally that in a left-handed NLTL analogue of the Su-Schrieffer-Heeger (SSH) lattice, harmonic generation is greatly increased by the presence of a topological edge state. Previous studies of nonlinear SSH circuits focused on solitonic behaviours at the fundamental harmonic. Here, we show that a topological edge mode at the first harmonic can produce strong propagating higher-harmonic signals, acting as a nonlocal cross-phase nonlinearity. We find maximum third-harmonic signal intensities five times that of a comparable conventional left-handed NLTL, and a 250-fold intensity contrast between topologically nontrivial and trivial configurations. This work advances the fundamental understanding of nonlinear topological states, and may have applications for compact electronic frequency generators.

4.
J Neurosurg ; : 1-3, 2019 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-30797198

RESUMO

Deep brain stimulation (DBS) is a well-established therapy for patients with advanced Parkinson's disease (PD), dystonia, and other movement disorders. In contrast to the strong positive effects that have been documented for motor symptoms, the effects of DBS on nonmotor symptoms have not been fully elucidated. Some reports suggest that stimulation of the subthalamic nucleus may improve lower urinary tract symptoms in patients with PD; however, reports of the effects of globus pallidus internus (GPi) DBS on urinary symptoms are limited. The authors present the case of a 49-year-old woman with PD who developed severe urinary incontinence after 27 months of GPi DBS. The urinary incontinence disappeared when stimulation was turned off, and reemerged after it was turned on again. After activation of a more dorsal contact in the left electrode, the patient's urinary dynamics returned to normal.

5.
Zhongguo Dang Dai Er Ke Za Zhi ; 21(1): 94-99, 2019 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-30675871

RESUMO

The widespread use of mechanical ventilation technology has contributed to the successful treatment of many children with respiratory failure. At the same time, forced ventilation and changes in normal respiratory physiology and mechanics may lead to respiratory dysfunction and decreased airway clearance ability. Therefore, how to perform a comprehensive and accurate respiratory function assessment, conduct appropriate respiratory function rehabilitation, perform extubation as soon as possible, and shorten the duration of mechanical ventilation based on the children's own physiological characteristics, is a focus of the research on effective weaning from mechanical ventilation in children with severe conditions. This article reviews the advances in the respiratory function assessment and treatment methods in children undergoing invasive mechanical ventilation.


Assuntos
Respiração Artificial , Insuficiência Respiratória , Extubação , Criança , Humanos , Respiração , Desmame do Respirador
6.
Acta Neurol Scand ; 2018 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-30451276

RESUMO

INTRODUCTION: Subthalamic deep brain stimulation (STN-DBS) has been reported to improve the quality of life (QoL) related to Parkinson's disease (PD). However, not all subjects are satisfied with the postsurgical QoL outcome. We aimed to detect the related factors and possible predictors to QoL improvement for those PD patients one year after STN DBS. MATERIALS & METHODS: 45 PD patients with bilateral STN-DBS surgery were included and followed up for 1 year. The Reliable Change Index (RCI) was adapted to determine the individual postsurgical QoL outcome. The changes of QoL were correlated with baseline parameters and the changes of progression parameters using Pearson's correlation. The exploratory stepwise regressions were adopted to detect the extents of baseline variables and progression parameters. The predictors to QoL outcome were detected using the logistic regression analysis. RESULTS: 51.1% of the patients reported a better QoL, 40.0% of patients reported an unchanged QoL, while 8.9% of patients reported a worsening of QoL. The subdomains of mobility, activity of daily living, cognition, and bodily discomfort improved significantly after the surgery. The presurgical factors including QoL, dopaminergic medication burden, disease stages, depression scores and postsurgical reductions in depression and non-motor scores were found to correlate with QoL changes. Furthermore, the greater presurgical QoL burden, lesser dopaminergic medication exposure and earlier disease stages were predictors to QoL improvements. CONCLUSION: The clinicians should carefully evaluate the non-motor symptoms and life quality in those patients at relatively earlier stages and with lower medicine dosage to get more successful DBS outcomes. This article is protected by copyright. All rights reserved.

7.
Haematologica ; 103(9): 1472-1483, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29880605

RESUMO

Acute myeloid leukemia is a disorder characterized by abnormal differentiation of myeloid cells and a clonal proliferation derived from primitive hematopoietic stem cells. Interventions that overcome myeloid differentiation have been shown to be a promising therapeutic strategy for acute myeloid leukemia. In this study, we demonstrate that CRISPR/Cas9-mediated knockout of dihydroorotate dehydrogenase leads to apoptosis and normal differentiation of acute myeloid leukemia cells, indicating that dihydroorotate dehydrogenase is a potential differentiation regulator and a therapeutic target in acute myeloid leukemia. By screening a library of natural products, we identified a novel dihydroorotate dehydrogenase inhibitor, isobavachalcone, derived from the traditional Chinese medicine Psoralea corylifolia Using enzymatic analysis, thermal shift assay, pull down, nuclear magnetic resonance, and isothermal titration calorimetry experiments, we demonstrate that isobavachalcone inhibits human dihydroorotate dehydrogenase directly, and triggers apoptosis and differentiation of acute myeloid leukemia cells. Oral administration of isobavachalcone suppresses subcutaneous HL60 xenograft tumor growth without obvious toxicity. Importantly, our results suggest that a combination of isobavachalcone and adriamycin prolonged survival in an intravenous HL60 leukemia model. In summary, this study demonstrates that isobavachalcone triggers apoptosis and differentiation of acute myeloid leukemia cells via pharmacological inhibition of human dihydroorotate dehydrogenase, offering a potential therapeutic strategy for acute myeloid leukemia.

8.
Chem Biol Drug Des ; 92(1): 1324-1332, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29582555

RESUMO

Plasmodium falciparum dihydroorotate dehydrogenase (PfDHODH) is a promising drug target for antimalarial chemotherapy. In our continuous efforts to develop more potent PfDHODH inhibitors, a unique library of active ingredients from traditional Chinese medicine (TCM) has been collected and was screened in this study. Through the initial screening, we found that coptisine, a natural alkaloid from TCM Coptidis Rhizoma, was a novel and potent inhibitor of PfDHODH with an IC50 value of 1.83 ± 0.08 µm. At the same time, enzyme kinetic analysis using Lineweaver-Burk plot indicated that coptisine is an uncompetitive inhibitor for PfDHODH. Thermal shift assay and molecular docking simulation research reveal that coptisine is capable of binding with PfDHODH. Moreover, coptisine exhibits weak inhibition activity against human DHODH, indicating that coptisine is a selective inhibitor of PfDHODH. Taken together, our study highlights the potential of active ingredients in TCM as valuable resource for discovering novel chemical scaffolds for PfDHODH.

9.
Hu Li Za Zhi ; 64(3): 33-42, 2017 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-28580557

RESUMO

BACKGROUND: Postoperative delirium is a significant complication in elderly patients. The occurrence of delirium may increase the related physical and psychological risks, delay the length of hospital stays, and even lead to death. According to the current evidence-based model, the application of interdisciplinary intervention may effectively prevent delirium, shorten the length of hospital stays, and save costs. PURPOSE: To establish a culturally appropriate interdisciplinary intervention model for preventing postoperative delirium in older Chinese patients. METHODS: The authors adapted the original version of the Hospital Elder Life Program (HELP©) from the Hebrew Senior Life Institute for Aging Research of Harvard University by localizing the content using additional medical resources and translating the modified instrument into Chinese. Furthermore, the final version of this interdisciplinary intervention model for postoperative delirium was developed in accordance with the "guideline of delirium: diagnosis, prevention and management produced by the National Institute for Health and Clinical Excellence in 2010" and the "clinical practice guideline for postoperative delirium in older adults" produced by American geriatrics society in 2014. Finally, the translated instrument was revised and improved using discussions, consultations, and pilot study. RESULTS: The abovementioned procedure generated an interdisciplinary intervention model for preventing postoperative delirium that is applicable to the Chinese medical environment. The content addresses personnel structure and assignment of responsibility; details of interdisciplinary intervention protocols and implementation procedures; and required personnel training. CONCLUSIONS: The revised model is expected to decrease the occurrence of post-operative delirium and other complications in elderly patients, to help them maintain and improve their function, to shorten the length of their hospital stays, and to facilitate recovery.


Assuntos
Delírio/prevenção & controle , Complicações Pós-Operatórias/prevenção & controle , Idoso , Humanos
10.
BMJ Open ; 6(11): e012983, 2016 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-27888176

RESUMO

OBJECTIVE: The purpose of this study was to investigate the characteristics of nailfold capillaroscopy associated with hand-arm vibration syndrome (HAVS). METHODS: In total, 113 male gold miners were recruited: 35 workers who were chronically exposed to vibration and developed vibration-induced white finger were defined as the HAVS group, 39 workers who were exposed to vibration but did not have HAVS were classified as the vibration-exposed controls (VEC) group, and 39 workers without vibration exposure were categorised as the non-VEC (NVEC) group. Video capillaroscopy was used to capture images of the 2nd, 3rd and 4th fingers of both hands. The following nailfold capillary characteristics were included: number of capillaries/mm, avascular areas, haemorrhages and enlarged capillaries. The experiments were carried out in the same winter. All characteristics were evaluated under blinded conditions. RESULTS: Significant differences in all morphological characteristics existed between the groups (p<0.05). Avascular areas in the HAVS, VEC and NVEC groups appeared in 74.3%, 43.6% and 25.0% of participants, respectively. A higher percentage of participants had haemorrhages in the HAVS group (65.7%) compared with the other groups (VEC: 7.7% and NVEC: 7.5%). The number of capillaries/mm, input limb width, output limb width, apical width, and ratio of output limb and input limb all had more than 70% sensitivity or specificity of their cut-off value. CONCLUSIONS: Nailfold capillary characteristics, especially the number of capillaries/mm, avascular areas, haemorrhages, output limb width, input limb width and apical width alterations, revealed significant associations with HAVS.


Assuntos
Dedos/irrigação sanguínea , Síndrome da Vibração do Segmento Mão-Braço/diagnóstico por imagem , Unhas/irrigação sanguínea , Exposição Ocupacional/efeitos adversos , Vibração/efeitos adversos , Adulto , Consumo de Bebidas Alcoólicas/epidemiologia , Estudos de Casos e Controles , China , Estudos Transversais , Dedos/diagnóstico por imagem , Humanos , Modelos Logísticos , Masculino , Angioscopia Microscópica , Pessoa de Meia-Idade , Mineração , Unhas/diagnóstico por imagem , Doenças Profissionais/etiologia , Sensibilidade e Especificidade , Fumar/epidemiologia
11.
J Enzyme Inhib Med Chem ; 31(sup4): 98-105, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27590167

RESUMO

Human lipoxygenases (LOXs) have been emerging as effective therapeutic targets for inflammatory diseases. In this study, we found that four natural 2-arylbenzo[b]furan derivatives isolated from Artocarpus heterophyllus exhibited potent inhibitory activities against human LOXs, including moracin C (1), artoindonesianin B-1 (2), moracin D (3), moracin M (4). In our in vitro experiments, compound 1 was identified as the most potent LOX inhibitor and the moderate subtype selective inhibitor of 12-LOX. Compounds 1 and 2 act as competitive inhibitors of LOXs. Moreover, 1 significantly inhibits LTB4 production and chemotactic capacity of neutrophils, and is capable of protecting vascular barrier from plasma leakage in vivo. In addition, the preliminary structure-activity relationship analysis was performed based on the above four naturally occurring (1-4) and six additional synthetic 2-arylbenzo[b]furan derivatives. Taken together, these 2-arylbenzo[b]furan derivatives, as LOXs inhibitors, could represent valuable leads for the future development of therapeutic agents for inflammatory diseases.


Assuntos
Benzofuranos/farmacologia , Inibidores de Lipoxigenase/química , Inibidores de Lipoxigenase/farmacologia , Lipoxigenase/metabolismo , Artocarpus/química , Benzofuranos/química , Benzofuranos/isolamento & purificação , Relação Dose-Resposta a Droga , Humanos , Lipoxigenase/isolamento & purificação , Inibidores de Lipoxigenase/isolamento & purificação , Estrutura Molecular , Relação Estrutura-Atividade
12.
Int J Ophthalmol ; 9(4): 512-8, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27162721

RESUMO

AIM: To investigate matrix metalloproteinases (MMPs) and tissue inhibitor of metalloproteinases (TIMPs) expression during the progress of fusarium solani (F.solani) keratitis in a rat model. METHODS: A rat model of F.solani keratitis was produced using corneal scarification and a hand-made contact lens. MMPs and TIMPs expressiond were explored in this rat model of F.solani keratitis using real-time polymerase chain reaction (PCR) and DIF. GM6001 (400 µmol/mL) was used to treat infected corneas. The keratitis duration, amount and area of corneal neovascularization (CNV) were evaluated. RESULTS: MMP-3 expression was 66.3 times higher in infected corneas compared to normal corneas. MMP-8, -9, and -13 expressions were significantly upregulated in the mid-period of the infection, with infected-to-normal ratios of 4.03, 39.86, and 5.94, respectively. MMP-2 and -7 expressions increased in the late period, with the infected-to-normal ratios of 5.94 and 16.22, respectively. TIMP-1 expression was upregulated in the early period, and it was 43.17 times higher in infected compared to normal corneas, but TIMP-2, -3, and -4 expressions were mildly downregulated or unchanged. The results of DIF were consistent with the result of real-time PCR. GM6001, a MMPs inhibitor, decreased the duration of F.solani infection and the amount and area of CNV. CONCLUSION: MMPs and TIMPs contributed into the progress of F.solani keratitis.

13.
Clin Hemorheol Microcirc ; 63(4): 335-347, 2016 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-26639766

RESUMO

OBJECTIVE: To explore whether polymorphic variants of the HTR1B gene are associated with the susceptibility of Raynauds' Phenomenon (RP) coursed by vibration. METHODS: 148 subjects exposed to vibration for more than 2 years were classified into either induced white finger (VWF) group (n = 72), or non-VWF group (n = 76). Vibration exposure levels were measured and assessed following ISO 5349-1:2001 protocol. All workers were genotyped by sequencing for the single nucleotide polymorphisms (SNPs) in the 5'-flanking and coding region of HTR1B. Genetic characteristics and linkage disequilibrium (LD) were analyzed with Haploview. Serum serotonin levels of each subject were detected using ELISA. The association between the susceptibility of vascular damage and genotype was analyzed via logistic regression. RESULTS: 7 known SNPs were obtained and their allele frequencies were inserted into the Hardy-Weinberg equilibrium. rs6297 variant genotype had an increased risk of VWF compared with wild genotype (OR = 2.14, 95% CI = 1.04- 4.58, P < 0.05). rs6298 mutant type (AG+GG) was found to have a significant interaction on vibration exposure LN(CEI), accounting for VWF occurrence. LN(5-HT) level is significantly different between the VWF group (x¯±s= 1.99±1.09 ng/mL) and the non-VWF group (x¯±s= 2.72±1.47 ng/mL). CONCLUSIONS: Serotonin levels may affect the progression of secondary RP. Polymorphic variants of the HTR1B gene are associated with the susceptibility of secondary RP in vibration-exposed occupational populations of Chinese Han people.


Assuntos
Braço/patologia , Mãos/patologia , Doenças Profissionais/genética , Doença de Raynaud/genética , Receptor 5-HT1B de Serotonina/genética , Vibração/efeitos adversos , Adulto , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Profissionais/patologia , Polimorfismo de Nucleotídeo Único , Doença de Raynaud/patologia
14.
Phys Rev Lett ; 115(22): 225301, 2015 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-26650309

RESUMO

A chiral d-wave superfluid is a preliminary example of interacting topological matter. However, unlike s-wave superfluids prevalent in nature, its existence requires a strong d-wave interaction, a criterion that is difficult to access in ordinary systems. There is no experimental observation of such unconventional superfluid at the moment. Here, we present a new principle for creating a two-dimensional (2D) chiral d-wave superfluid using periodically driven lattices. Because of an imprinted 2D pseudospin-orbit coupling, where the sublattice index serves as the pseudospin, the s-wave interaction between two hyperfine spin states naturally creates a chiral d-wave superfluid. This scheme can be directly implemented in current experiments.

15.
Yao Xue Xue Bao ; 49(5): 622-6, 2014 May.
Artigo em Chinês | MEDLINE | ID: mdl-25151731

RESUMO

Hypoxia-inducible factor-1 (HIF-1) is a key transcription factor on hypoxia responses in mammalian tissues. HIF-1 plays as a positive factor in solid tumor and leads to hypoxia-driven responses that enhance its downstream gene expression for tumor growth and survival. LXY6099 was obtained by the structural modification and optimization of manassantin A (MA) as a high potent HIF-1 inhibitor. Antitumor activity of LXY6099 was observed in this study. LXY6099 with an IC50 value of 2.46 x 10(-10) mol x L(-1) showed more sensitive inhibition activity to HIF-1 than that of MA detected by reporter gene assay (> 100 folds). It showed strong inhibition on the growth of human solid tumor cell lines. Furthermore, LXY6099 exhibited significant antitumor activity against established human tumor xenografts in nu/nu mice with treatment of MX-1 breast cancer. Thus, LXY6099 as a novel HIF-1 inhibitor could be further developed into anti-cancer agents.


Assuntos
Antineoplásicos/farmacologia , Fator 1 Induzível por Hipóxia/metabolismo , Lignanas/farmacologia , Animais , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Xenoenxertos , Humanos , Camundongos Nus
16.
Mitochondrial DNA ; 25(5): 348-9, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23848213

RESUMO

Abstract The complete mitochondrial genome of Filchnerella beicki Ramme, 1931, which was collected from the Ningxia Hui Autonomous Region of China, is reported here. It is 15,658 bp in length and contains 72.3% AT. All Filchnerella beicki protein-coding sequences start with a typical ATN codon, excluding cox1. The usual termination codon (TAN) and incomplete stop codons (T) were found from 13 protein-coding genes. All tRNA genes could be folded into the typical cloverleaf secondary structure, excluding trnS(AGN) which forms another structure. The sizes of the large and small ribosomal RNA genes are 1315 and 853 bp, respectively. The AT content of the A+T-rich region is 83.1%.


Assuntos
Genoma Mitocondrial , Ortópteros/genética , RNA de Transferência/química , Animais , China , Genes Mitocondriais , Genoma de Inseto , Dados de Sequência Molecular , Ortópteros/citologia , Análise de Sequência de DNA
17.
Artigo em Chinês | MEDLINE | ID: mdl-25608899

RESUMO

OBJECTIVE: To investigate the efficacy of mouse nerve growth factor (mNGF) in treating occupational hand-arm vibration disease (HAVD). METHODS: Sixty-four patients with HAVD were equally and randomly divided into treatment group and control group. The control group was given Salvia miltiorrhiza Bunge and deproteinized extract of calf blood to improve circulation, and also given methylcobalamin tablets and vitamin B6 for neurotrophic treatment. In addition to the above treatments for the control group, the treatment group was also given 30 µg/d mNGF by intramuscular injection for two courses (4 weeks for each course) with a 15-day interval. RESULTS: Both the treatment group and the control group showed significant improvements in clinical symptoms and signs (hand numbness and pain, and reduced senses of touch, pain, and vibration), cold water loading test (CWLT), and electroneuromyography (ENMG) after treatments (P < 0.05). And the treatment group had significantly more improvements than the control group (P < 0.05). CONCLUSION: mNGF can significantly improve hand numbness and pain, reduced senses of touch, pain, and vibration, CWLT, and ENMG, so it has better clinical effect and safety in treating HAVD. Early diagnosis and treatment can improve the outcome of patients with HAVD.


Assuntos
Síndrome da Vibração do Segmento Mão-Braço/tratamento farmacológico , Fator de Crescimento Neural/farmacologia , Animais , Humanos , Camundongos , Doenças Profissionais , Resultado do Tratamento , Vibração
18.
Nanoscale ; 5(24): 12394-8, 2013 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-24162503

RESUMO

Using first-principles molecular dynamics simulations, we demonstrate that the penetration of lithium atoms into a silicon nanowire (SiNW) self-stops once a metallic amorphous Li-Si shell forms. This explains the extended life of crystalline Si cores in SiNW battery electrodes observed in experiments. Metallic Li-Si shells grasp Li atoms and prohibit them from directly segregating through interstitial channels toward the crystalline center of SiNWs. Meanwhile, high pressure develops on the core as it shrinks, due to the expansion and tension in the amorphous shell, which eventually frustrate the step-forward amorphization. We also elucidate the reasons why H-passivated SiNWs are not suitable for studies of lithiation processes.

19.
PLoS One ; 8(7): e69272, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23869239

RESUMO

OBJECTIVE: To comprehensively analyze the relationship between exposure to extremely low frequency electromagnetic fields (ELF-EMFs) and the development of female breast cancer. METHODS: Reports of case-control studies published from 1990 to 2010 were analyzed. The quality effect model was chosen to calculate total odds ratio (OR) depending on the data in studies and quality scores. Subgroup analyses were also performed by the situation of menopause, estrogenic receptor and exposure assessment respectively. RESULTS: For all 23 studies the OR was 1.07, 95% CI=1.02-1.13, for estrogen receptor positive subgroup,OR=1.11, 95% CI=1.03-1.20; for premenopausal subgroup, OR=1.11, 95% CI=1.00-1.23. The results of other subgroups showed no significant association between ELF-EMF and female breast cancer. CONCLUSION: ELF-EMFs might be related to an increased risk for female breast cancer, especially for premenopausal and ER+ females. However, it's necessary to undertake better epidemiologic researches to verify the association between ELF-EMF and female breast cancer due to the limits of current study, especially the one on exposure assessment.


Assuntos
Neoplasias da Mama/etiologia , Campos Eletromagnéticos , Exposição Ambiental , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Humanos , Medição de Risco
20.
Phys Rev Lett ; 110(17): 176403, 2013 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-23679750

RESUMO

We study the competition of disorder and superconductivity for a one-dimensional p-wave superconductor in incommensurate potentials. With the increase in the strength of the incommensurate potential, the system undergoes a transition from a topological superconducting phase to a topologically trivial localized phase. The phase boundary is determined both numerically and analytically from various aspects and the topological superconducting phase is characterized by the presence of Majorana edge fermions in the system with open boundary conditions. We also calculate the topological Z2 invariant of the bulk system and find it can be used to distinguish the different topological phases even for a disordered system.

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