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1.
J Prev Alzheimers Dis ; 11(3): 589-600, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38706275

RESUMO

BACKGROUND: Alzheimer's disease (AD), the most common type of irreversible dementia, is predicted to affect 152 million people by 2050. Evidence from large-scale preventive randomized controlled trials (RCTs) on modifiable risk variables in Europe has shown that multi-domain lifestyle treatments for older persons at high risk of dementia may be practical and effective. Given the substantial differences between the Chinese and European populations in terms of demographics and living conditions, direct adoption of the European program in China remains unfeasible. Although a RCT has been conducted in China previously, its participants were mainly from rural areas in northern China and, thus, are not representative of the entire nation.There is an urgent need to establish cohorts that represent different economic, cultural, and geographical situations in order to explore implementation strategies and evaluate the effects of early multi-domain interventions more comprehensively and accurately. MEDTODS: We developed an integrated intervention procedure implemented in urban neighborhood settings, namely China Initiative for Multi-Domain Intervention (CHINA-IN-MUDI). CHINA-IN-MUDI is a 2-year multicenter open-label cluster-randomised controlled trial centered around a Chinese-style multi-domain intervention to prevent cognitive decline. Participants aged 60-80 years were recruited from a nationally representative study, i.e. China Healthy Aging and Dementia Study cohort. An external harmonization process was carried out to preserve the original FINGER design. Subsequently, we standardized a series of Chinese-style intervention programs to align with cultural and socioeconomic status. Additionally, we expanded the secondary outcome list to include genomic and proteomic analyses. To enhance adherence and facilitate implementation, we leveraged an e-health application. RESULTS: Screening commenced in July 2022. Currently, 1,965 participants have been randomized into lifestyle intervention (n = 772) and control groups (n = 1,193). Both the intervention and control groups exhibited similar baseline characteristics. Several lifestyle and vascular risk factors were present, indicating a potential window of opportunity for intervention. The intervention will be completed by 2025. CONCLUSIONS: This project will contribute to the evaluation of the effectiveness and safety of intervention strategies in controlling AD risk and reducing clinical events, providing a basis for public health decision-making in China.


Assuntos
Disfunção Cognitiva , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Alzheimer/prevenção & controle , China/epidemiologia , Disfunção Cognitiva/prevenção & controle , Estilo de Vida
2.
Artigo em Chinês | MEDLINE | ID: mdl-37339898

RESUMO

Objective: This cross-sectional investigation aimed to determine the incidence, clinical characteristics, prognosis, and related risk factors of olfactory and gustatory dysfunctions related to infection with the SARS-CoV-2 Omicron strain in mainland China. Methods: Data of patients with SARS-CoV-2 from December 28, 2022, to February 21, 2023, were collected through online and offline questionnaires from 45 tertiary hospitals and one center for disease control and prevention in mainland China. The questionnaire included demographic information, previous health history, smoking and alcohol drinking, SARS-CoV-2 vaccination, olfactory and gustatory function before and after infection, other symptoms after infection, as well as the duration and improvement of olfactory and gustatory dysfunction. The self-reported olfactory and gustatory functions of patients were evaluated using the Olfactory VAS scale and Gustatory VAS scale. Results: A total of 35 566 valid questionnaires were obtained, revealing a high incidence of olfactory and taste dysfunctions related to infection with the SARS-CoV-2 Omicron strain (67.75%). Females(χ2=367.013, P<0.001) and young people(χ2=120.210, P<0.001) were more likely to develop these dysfunctions. Gender(OR=1.564, 95%CI: 1.487-1.645), SARS-CoV-2 vaccination status (OR=1.334, 95%CI: 1.164-1.530), oral health status (OR=0.881, 95%CI: 0.839-0.926), smoking history (OR=1.152, 95%CI=1.080-1.229), and drinking history (OR=0.854, 95%CI: 0.785-0.928) were correlated with the occurrence of olfactory and taste dysfunctions related to SARS-CoV-2(above P<0.001). 44.62% (4 391/9 840) of the patients who had not recovered their sense of smell and taste also suffered from nasal congestion, runny nose, and 32.62% (3 210/9 840) suffered from dry mouth and sore throat. The improvement of olfactory and taste functions was correlated with the persistence of accompanying symptoms(χ2=10.873, P=0.001). The average score of olfactory and taste VAS scale was 8.41 and 8.51 respectively before SARS-CoV-2 infection, but decreased to3.69 and 4.29 respectively after SARS-CoV-2 infection, and recovered to 5.83and 6.55 respectively at the time of the survey. The median duration of olfactory and gustatory dysfunctions was 15 days and 12 days, respectively, with 0.5% (121/24 096) of patients experiencing these dysfunctions for more than 28 days. The overall self-reported improvement rate of smell and taste dysfunctions was 59.16% (14 256/24 096). Gender(OR=0.893, 95%CI: 0.839-0.951), SARS-CoV-2 vaccination status (OR=1.334, 95%CI: 1.164-1.530), history of head and facial trauma(OR=1.180, 95%CI: 1.036-1.344, P=0.013), nose (OR=1.104, 95%CI: 1.042-1.171, P=0.001) and oral (OR=1.162, 95%CI: 1.096-1.233) health status, smoking history(OR=0.765, 95%CI: 0.709-0.825), and the persistence of accompanying symptoms (OR=0.359, 95%CI: 0.332-0.388) were correlated with the recovery of olfactory and taste dysfunctions related to SARS-CoV-2 (above P<0.001 except for the indicated values). Conclusion: The incidence of olfactory and taste dysfunctions related to infection with the SARS-CoV-2 Omicron strain is high in mainland China, with females and young people more likely to develop these dysfunctions. Active and effective intervention measures may be required for cases that persist for a long time. The recovery of olfactory and taste functions is influenced by several factors, including gender, SARS-CoV-2 vaccination status, history of head and facial trauma, nasal and oral health status, smoking history, and persistence of accompanying symptoms.


Assuntos
COVID-19 , Transtornos do Olfato , Feminino , Humanos , Adolescente , SARS-CoV-2 , Olfato , COVID-19/complicações , Estudos Transversais , Vacinas contra COVID-19 , Incidência , Transtornos do Olfato/epidemiologia , Transtornos do Olfato/etiologia , Distúrbios do Paladar/epidemiologia , Distúrbios do Paladar/etiologia , Prognóstico
3.
Sci Rep ; 13(1): 6333, 2023 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-37072459

RESUMO

Bulk Bi0.5Sr0.5Fe0.5Cr0.5O3 (BSFCO) is a new compound comprising the R3c structure. The structural, magnetic property and exchange bias (EB) details are investigated. The material was in the super-paramagnetic (SP) state at room temperature. Exchange bias usually occurs at the boundary between different magnetic states after field cooling (HFC) acts on the sample. Here the result shows that changing HFC from 1 to 6 T reduces the HEB value by 16% at 2 K at the same time. Meanwhile, HEB diminishes as the ferromagnetic layer thickness increases. The variation of (the thickness of ferromagnetic layer) tFM with the change of HFC leads to the tuning of HEB by HFC in BSFCO bulk. These effects are obviously different from the phenomenon seen in other oxide types.

4.
J Phys Condens Matter ; 33(13): 135803, 2021 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-33527915

RESUMO

In this work we report experimental evidence for the weak high-temperature ferromagnetism in Bi1-x R x FeO3 (R = Dy, Y) compounds by systematic characterizations, excluding the possible side-effects from other iron-based impurities. Remarkable saturated magnetic moment was observed in the Y-substituted samples, Bi1-x Y x FeO3, which is larger than the moment obtained in Bi1-x Dy x FeO3, the Dy-substituted samples with antiferromagnetic background. The physical origin of the weak ferromagnetic transition is discussed and serious lattice distortions have been identified based on the x-ray diffraction and Raman scattering data, although the rhombohedral structure symmetry remains unchanged upon the substitutions. It is believed that the structural distortion suppressed cycloid spin structure is the main factor for the enhanced magnetization in Bi1-x R x FeO3 compounds. Additionally, the Dy3+-Fe3+ antiferromagnetic coupling, which strengthens the antiferromagnetic interaction in Bi1-x Dy x FeO3 compounds, acts as the driving force for the magnetic discrepancy between Bi1-x Y x FeO3 and Bi1-x Dy x FeO3 samples.

5.
Int Nurs Rev ; 66(1): 30-42, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29956825

RESUMO

BACKGROUND: Case management has been adopted in Korea and been recognized as a promising care-coordination method that lowers costs and improves quality of care. However, the effectiveness of case management among individuals with chronic illnesses who reside in the community has yet to be established. AIM: This systematic review identifies and synthesizes recent evidence of case management's effectiveness in managing chronic illnesses among adults in Korea. METHODS: The methodology of this systematic review was guided by the Cochrane processes and PRISMA statements. A search of multiple bibliographic databases to identify studies of case management in the populations of Koreans adult with chronic illnesses was conducted. Studies that met the inclusion criteria were published in English or Korean. Nine empirical peer-reviewed studies published between 2008 and 2016 were selected for review. RESULTS: The retrieved studies show that case management programmes in Korea for adults with chronic illness in the community were led by nurses. There was strong evidence that nurse-led case management was effective in improving psychobehavioural and objective clinical outcomes; however, results for health services utilization outcomes were mixed. CONCLUSION: In future, research with rigorous study designs and large sample size in multiple settings are needed to further assess the effectiveness of case management in Korea. IMPLICATIONS FOR NURSING AND HEALTH POLICY: Nurse-led case management would be of support in the care of chronic illnesses not only in Korea but also in Asian countries which share standard practice of case management with Korea. Nursing leaders should allocate resources to sponsor educational resources and practical strategies for evidence-based case management.


Assuntos
Administração de Caso/organização & administração , Doença Crônica/terapia , Atenção à Saúde/organização & administração , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , República da Coreia
6.
Scand J Rheumatol ; 47(5): 392-399, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29916287

RESUMO

OBJECTIVE: Despite aggressive therapeutic regimens, diffuse alveolar haemorrhage (DAH) is still associated with a high mortality rate in systemic lupus erythematosus (SLE). This study was carried out in patients with SLE-associated DAH with a focus on their therapeutic modality. METHOD: A retrospective review was performed in 839 Han Chinese lupus patients hospitalized for their DAH manifestation from May 2006 to December 2016. RESULTS: There were 24 episodes in 17 cases (2.0% incidence), 15 females and two males aged 19-67 years (mean ± sd 38.2 ± 15.1 years). High disease activity [Systemic Lupus Erythematosus Disease Activity Index 2000 (SLEDAI-2K) 12-31, 19.8 ± 5.6] was found at the onset of DAH. All patients were treated with high-dose corticosteroid, followed by pulse methylprednisolone (70.6%), plasmapheresis (41.2%), pulse cyclophosphamide (35.3%), and rituximab (23.5%). Six patients (35.3%), including three with extracorporeal membrane oxygenation, died owing to acute respiratory failure. All patients receiving rituximab treatment survived with a follow-up period of 12-58 months (40.8 ± 21.1 months), and no further relapse was noted in three cases with a history of recurrent DAH episodes. In addition, there was a significant decrease in their lupus activity (SLEDAI-2K 21.5 ± 6.0 to 6.3 ± 1.7, p = 0.0286). CONCLUSION: In this single-centre series with SLE-associated DAH in Han Chinese patients, a beneficial effect of rituximab therapy was observed.


Assuntos
Hemorragia/etiologia , Pneumopatias/etiologia , Lúpus Eritematoso Sistêmico/complicações , Adulto , Idoso , Povo Asiático , Oxigenação por Membrana Extracorpórea/métodos , Feminino , Glucocorticoides/uso terapêutico , Hemorragia/mortalidade , Hemorragia/terapia , Humanos , Fatores Imunológicos/uso terapêutico , Pneumopatias/mortalidade , Pneumopatias/terapia , Lúpus Eritematoso Sistêmico/mortalidade , Lúpus Eritematoso Sistêmico/terapia , Masculino , Pessoa de Meia-Idade , Plasmaferese/métodos , Alvéolos Pulmonares/patologia , Recidiva , Estudos Retrospectivos , Rituximab/uso terapêutico , Análise de Sobrevida , Taiwan , Adulto Jovem
7.
Int Nurs Rev ; 65(1): 102-113, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29336031

RESUMO

AIM: This qualitative systematic review aimed to identify and synthesize recent qualitative studies to improve understanding of the experiences and perceptions of case management interventions that individuals with chronic illnesses and their caregivers have. BACKGROUND/INTRODUCTION: Case management has been shown to be effective at improving quality of care and lowering costs for individuals with chronic illnesses. However, no qualitative review has been synthesized with recent qualitative studies about case management experiences by individual with chronic illnesses. METHODS: This qualitative systematic review uses a thematic synthesis method to review 10 qualitative studies published within the last 10 years, from 2007 to 2016, thereby identifying and discussing the understandings that individuals with chronic illnesses and their caregivers have about case management. RESULTS: From this synthesis, three themes were identified as facilitators of case management (access to healthcare resources, health status supports and emotional aid) and two themes were identified as barriers to it (low information about case management and time constraints). CONCLUSIONS: This is the first qualitative systematic review of the perceptions and experiences that individuals with chronic illnesses and their caregivers have about case management. The facilitators of case management can be employed to inform patients about the benefits of case management and to improve population health. IMPLICATIONS FOR NURSING AND HEALTH POLICY: The findings about barriers to case management can be used to reform case management for populations with chronic illnesses. These factors should be considered by nursing researchers and healthcare policymakers when implementing case management.


Assuntos
Administração de Caso/organização & administração , Doença Crônica/enfermagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Cuidadores , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pesquisa em Enfermagem , Pesquisa Qualitativa
8.
Int Nurs Rev ; 64(2): 296-308, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27861853

RESUMO

AIM: This systematic review synthesizes recent evidence of the effectiveness of case management in reducing hospital use by individuals with chronic illnesses. BACKGROUND: Hospital use by individuals with chronic illnesses accounts for 66% of healthcare costs in the United States. its has been cited as care coordination that can reduce healthcare costs; however, its effectiveness in improving hospital use outcomes is contradictory, and no review has yet synthesized recent studies of case management with respect to hospital use outcomes. METHODS: This systematic review followed the Cochrane processes and was guided by use of PRISMA statements. Five electronic databases were searched to obtain randomized controlled trials published within the last 10 years that evaluated case management hospital use as a primary outcome by individuals with chronic illnesses. RESULTS: Ten studies published between 2007 and 2015 were retrieved and assessed for risk of methodological bias. All studies used case management as an intervention, focused on transitional care services and reported hospital use, including readmissions and emergency department and hospital visits, as a primary outcome. Analysis of the studies showed that case management greatly reduced hospital readmissions and emergency department visits. LIMITATIONS: Only studies published in English were searched, and retrieved studies tended to report positive results. CONCLUSIONS: There was strong evidence of significant reductions in hospital use with case management as an intervention. However, other results about the efffectiveness of case management remain mixed; more rigorously designed studies with case management interventions are needed. IMPLICATIONS FOR NURSING AND HEALTH POLICY: The complexity and cost of chronic illnesses means that case management should be considered as a tool to improve quality of care and lower healthcare costs.


Assuntos
Administração de Caso , Serviço Hospitalar de Emergência/estatística & dados numéricos , Hospitalização/estatística & dados numéricos , Doença Crônica , Humanos
9.
Sci Rep ; 6: 34767, 2016 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-27713482

RESUMO

The magnetically induced electric polarization behaviors in multiferroic TmMn2O5 in response to varying temperature and magnetic field are carefully investigated by means of a series of characterizations including the high precision pyroelectric current technique. Here polycrystalline rather than single crystal samples are used for avoiding the strong electrically self-polarized effect in single crystals, and various parallel experiments on excluding the thermally excited current contributions are performed. The temperature-dependent electric polarization flop as a major character is identified for different measuring paths. The magneto-current measurements indicate that the electric polarization in the low temperature magnetic phase region has different origin from that in the high temperature magnetic phase. It is suggested that the electric polarization does have multiple components which align along different orientations, including the Mn3+-Mn4+-Mn3+ exchange striction induced polarization PMM, the Tm3+-Mn4+-Tm3+ exchange striction induced polarization PTM, and the low temperature polarization PLT probably associated with the Tm3+ commensurate phase. The observed electric polarization flop can be reasonably explained by the ferrielectric model proposed earlier for DyMn2O5, where PMM and PTM are the two antiparallel components both along the b-axis and PLT may align along the a-axis. Finally, several issues on the unusual temperature dependence of ferroelectric polarizations are discussed.

10.
Sci Rep ; 6: 27840, 2016 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-27297396

RESUMO

It is known that the electro-transport and magnetism of perovskite alkaline-earth ruthenate oxides are sensitive to the lattice distortion associated with the A-site cation size. Orthorhombic CaRuO3 and cubic BaRuO3 exhibit distinctly different electro-transport and magnetic properties from orthorhombic SrRuO3. It has been suggested that SrRuO3 can be robust against some intrinsic/external perturbations but fragile against some others in terms of electro-transport and magnetism, and it is our motivation to explore such stability against the local site cation disorder. In this work, we prepare a set of SrRuO3-based samples with identical averaged A-site size but different A-site cation disorder (size mismatch) by Ca and Ba co-substitution of Sr. It is revealed that the electro-transport and magnetism of SrRuO3 demonstrate relatively high stability against this A-site cation disorder, characterized by the relatively invariable electrical and magnetic properties in comparison with those of SrRuO3 itself. A simple electro-transport network model is proposed to explain quantitatively the measured behaviors. The present work suggests that SrRuO3 as an itinerant electron ferromagnetic metal possesses relatively high robustness against local lattice distortion and cation occupation disorder.

11.
Genet Mol Res ; 15(2)2016 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-27173231

RESUMO

Bone fractures or bones subjected to open conduction and internal fixation are easily infected by bacteria; bacterial lipopolysaccharide (LPS) has been recognized as an important pathogenic factor affecting bone fracture healing. Therefore, the effect of LPS on bone metabolism is relevant for bone healing. In this study, we investigated the effect of LPS on the expression of Toll-like receptor (TLR)-4 (an LPS receptor) by using real-time quantitative PCR and western blotting. We also examined the regulatory role of LPS in osteoblast differentiation by measuring the ALP activity, matrix mineralization, and ALP, OCN, and Runx2 mRNA (essential factors affecting osteoblast differentiation) expression in LPS-treated mouse osteoblast MC3T3-E1 cells. We also evaluated the effect of TLR-4 on LPS-mediated inhibition of osteoblast differentiation using RNA interference. LPS promotes TLR-4 mRNA and protein expression in MC3T3-E1 cells (P < 0.05, P < 0.01 or P < 0.001), and inhibits osteoblast differentiation by downregulating matrix mineralization and ALP activity (P < 0.05, P < 0.01 or P < 0.001), and suppressing the expression ALP, OCN, and Runx2 mRNA in MC3T3-E1 cells (P < 0.05 or P < 0.01). Conversely, RNAi-mediated TLR-4 knockdown abrogates the LPS-mediated inhibition of osteoblast differentiation (P < 0.05 or P < 0.01). In summary, LPS was shown to inhibit osteoblast differentiation by suppressing the expression of ALP, OCN, and Runx2 in a TLR-4-dependent manner. The results of this study may provide insights into the signal pathway of LPS-induced bone loss or delayed bone fracture healing.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Fraturas Ósseas/genética , Osteoblastos/metabolismo , Receptor 4 Toll-Like/biossíntese , Proteínas Adaptadoras de Transdução de Sinal/biossíntese , Animais , Linhagem Celular , Subunidade alfa 1 de Fator de Ligação ao Core/biossíntese , Fraturas Ósseas/tratamento farmacológico , Fraturas Ósseas/patologia , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Lipopolissacarídeos/administração & dosagem , Proteínas de Membrana/biossíntese , Camundongos , Osteoblastos/patologia , Osteogênese/efeitos dos fármacos , RNA Mensageiro/genética , Transdução de Sinais/efeitos dos fármacos , Receptor 4 Toll-Like/genética
12.
Oncogene ; 35(46): 6015-6025, 2016 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-27065318

RESUMO

ErbB2 is a vital breast cancer gene and its overexpression has a decisive role in breast tumor initiation and malignant progression. However, the molecular mechanisms that underlie ErbB2 dysregulation in breast cancer cells remain incompletely understood. In this study, we found that ErbB2 expression is inversely correlated with the level of miR-155, a well-documented oncogenic miRNA, in ErbB2-positive breast tumors. We further determined that miR-155 potently suppresses ErbB2 in breast cancer cells. Mechanistically, miR-155 acts to downregulate ErbB2 via two distinct mechanisms. First, miR-155 represses ErbB2 transcription by targeting HDAC2, a transcriptional activator of ErbB2. Second, miR-155 directly targets ErbB2 via a regulatory element in its coding region. Intriguingly, miR-155 is upregulated by trastuzumab and in turn leads to a reduction of ErbB2 expression in trastuzumab-treated ErbB2-positive breast cancer cells. Functional studies showed that miR-155 inhibits ErbB2-induced malignant transformation of human breast epithelial cells. Thus, our findings reveal an intriguing miR-155-ErbB2 context in regulating the malignant transformation of breast epithelial cells, and thereby indicate a novel mode of action for miR-155 in ErbB2-positive breast cancer.


Assuntos
Neoplasias da Mama/genética , Transformação Celular Neoplásica/genética , Células Epiteliais/metabolismo , MicroRNAs/genética , Receptor ErbB-2/genética , Regiões 3' não Traduzidas , Animais , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Modelos Animais de Doenças , Células Epiteliais/patologia , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Xenoenxertos , Histona Desacetilase 2/genética , Histona Desacetilases/genética , Humanos , Camundongos , Modelos Biológicos , Biossíntese de Proteínas , Interferência de RNA , RNA Mensageiro/genética , Sequências Reguladoras de Ácido Nucleico , Proteínas Repressoras/genética , Trastuzumab/farmacologia
13.
Genet Mol Res ; 14(4): 13779-90, 2015 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-26535693

RESUMO

The US2 protein has been reported to contribute to duck enteritis virus (DEV) infection; however, its kinetics and localization during infection, and whether it is a component of virion, have not been previously reported. To elucidate the function of DEV US2, US2 was amplified by polymerase chain reaction (PCR) and inserted into pET-32a(+); this was expressed, the recombinant US2 protein was purified, and a polyclonal antibody generated. In addition, the kinetics and localization of the US2 gene and protein were determined by quantitative real-time fluorescent PCR, ganciclovir (GCV), and cycloheximide (CHX) treatment, western-blot, and indirect immunofluorescence assay. The packaging of US2 into DEV virions was revealed by a protease protection assay. US2 was found to be transcribed 24 h post-infection (pi) and peaked at 72 h pi; the US2 protein was detected 48 h pi, except in the presence of GCV or CHX. US2 was packed into virions and also localized to the plasma membrane and cytoplasm in infected cells. The results showed that the DEV US2 is a late gene, and that its encoding protein could be a tegument component localized mainly in the cytoplasm. This study provides useful data for the further analysis of DEV US2, including an explanation for the genetic conservation among alphaherpesviruses.


Assuntos
Mardivirus/genética , Proteínas do Envelope Viral/genética , Animais , Linhagem Celular , Patos , Fibroblastos , Expressão Gênica , Mardivirus/efeitos dos fármacos , Transporte Proteico , Proteínas Recombinantes , Proteínas do Envelope Viral/isolamento & purificação , Proteínas do Envelope Viral/metabolismo , Vírion
14.
Phys Chem Chem Phys ; 17(32): 20961-70, 2015 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-26214759

RESUMO

Double-perovskite A2BB'O6 oxides with magnetic B and B' ions and E*-type antiferromagnetic order (E*-AFM, i.e. the ↑↑↓↓ structure) are believed to exhibit promising multiferroic properties, and Y2CoMnO6 (YCMO) is one candidate in this category. However, the microscopic origins for magnetically induced ferroelectricity in YCMO remain unclear. In this study, we perform detailed symmetry analysis on the exchange striction effect and lattice distortion, plus the first-principles calculations on YCMO. The E*-AFM state as the ground state with other competing states such as ferromagnetic and A-antiferromagnetic orders is confirmed. It is observed that the ferroelectricity is generated by the exchange striction associated with the E*-AFM order and chemically ordered Mn/Co occupation. Both the lattice symmetry consideration and first-principles calculations predict that the electric polarization aligns along the b-axis. The calculated polarization reaches up to 0.4682 µC cm(-2), mainly from the ionic displacement contribution. The present study presents a comprehensive understanding of the multiferroic mechanisms in YCMO and is of general significance for predicting emergent multiferroicity in other double-perovskite magnetic oxides.

15.
Sci Rep ; 5: 9922, 2015 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-25909460

RESUMO

The eg-orbital double-exchange mechanism as the core of physics of colossal magnetoresistance (CMR) manganites is well known, which usually covers up the role of super-exchange at the t2g-orbitals. The role of the double-exchange mechanism is maximized in La0.7Ca0.3MnO3, leading to the concurrent metal-insulator transition and ferromagnetic transition as well as CMR effect. In this work, by a set of synchronous Ru-substitution and Ca-substitution experiments on La0.7-yCa0.3+yMn1-yRuyO3, we demonstrate that the optimal ferromagnetism in La0.7Ca0.3MnO3 can be further enhanced. It is also found that the metal-insulator transition and magnetic transition can be separately modulated. By well-designed experimental schemes with which the Mn(3+)-Mn(4+) double-exchange is damaged as weakly as possible, it is revealed that this ferromagnetism enhancement is attributed to the Mn-Ru t2g ferromagnetic super-exchange. The present work allows a platform on which the electro-transport and magnetism of rare-earth manganites can be controlled by means of the t2g-orbital physics of strongly correlated transition metal oxides.

16.
Genet Mol Res ; 13(3): 7184-9, 2014 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-25222224

RESUMO

MicroRNAs (miRNAs) are thought to play a role in cancer development. We conducted a case-control study to investigate the association between polymorphisms in miR-149C>T and hepatocellular carcinoma (HCC) risk. Duplex polymerase chain reaction with the confronting 2-pair primers were taken to genotype miR-149C>T. The association between genotype frequencies of miR-149C>T and risk of HCC was estimated as odds ratios (ORs) and 95% confidence intervals (95%CIs) using conditional regression analysis. Logistical regression analysis showed that the miR-149 CC genotype and C allele were associated with risk of HCC, with adjusted ORs (95%CI) of 2.07 (1.32-3.26) and 1.42 (1.06-2.12), respectively. Using the TT+TC genotype as a reference, individuals carrying the CC genotype were associated with non-significant increased risk of HCC, adjusted OR (95%CI) of 1.37 (0.91-2.07). Subgroup analysis showed that HBV-infected subjects carrying the miR-149 TC+CC genotype (OR=5.85, 95%CI=2.49-13.77) had an increased risk of HCC. In summary, our study found that miRNA-149C>T polymorphism is associated with risk of HCC, especially in HBV-infected patients.


Assuntos
Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , MicroRNAs , Polimorfismo de Nucleotídeo Único , Idoso , Alelos , Povo Asiático , Carcinoma Hepatocelular/etiologia , Carcinoma Hepatocelular/patologia , Estudos de Casos e Controles , China , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Genótipo , Humanos , Neoplasias Hepáticas/etiologia , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Razão de Chances , Fatores de Risco , Carga Tumoral
17.
Poult Sci ; 93(9): 2184-92, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25012848

RESUMO

Duck hepatitis A virus (DHAV) is an infectious pathogen causing fatal duck viral hepatitis in ducklings. Although both the inactivated vaccines and live attenuated vaccines have been used to protect ducklings, DHAV-1 and DHAV-3 still cause significant serious damage to the duck industry in China and South Korea. For rapid detection, differentiation, and epidemic investigation of DHAV in China, a genotype-specific 1-step duplex reverse-transcription (RT) PCR assay was established in this study. The sensitivity and specificity of the developed RT-PCR assay was evaluated with nucleic acids extracted from 2 DHAV reference strains, and 9 other infectious viruses and bacteria. The genotype-specific primers amplified different size DNA fragments encompassing the complete VP1 gene of the DHAV-1 or DHAV-3. The assay detected the liver samples collected from experimentally infected ducklings and dead ducklings collected from different regions of China. Sequence analysis of these DNA fragments indicated that VP1 sequences of DHAV-1 can be used to distinguish wild type and vaccine strains. The phylogenetic analysis of VP1 sequences indicated that the developed RT-PCR assay can be used for epidemic investigation of DHAV-1 and DHAV-3. The developed RT-PCR assay can be used as a specific molecular tool for simultaneous detection, differentiation, and sequencing the VP1 gene of DHAV-1 and DHAV-3, which can be used for understanding the epidemiology and evolution of DHAV.


Assuntos
Patos , Vírus da Hepatite A/genética , Hepatite A/veterinária , Doenças das Aves Domésticas/virologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária , Proteínas Estruturais Virais/genética , Virologia/métodos , Animais , Hepatite A/virologia , Vírus da Hepatite A/classificação , Vírus da Hepatite A/isolamento & purificação , Vírus da Hepatite A/metabolismo , Dados de Sequência Molecular , Filogenia , Sensibilidade e Especificidade , Análise de Sequência de DNA/veterinária , Proteínas Estruturais Virais/metabolismo
18.
J Phys Condens Matter ; 26(30): 305901, 2014 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-25007855

RESUMO

Competing interactions make the magnetic structure of MnWO4 highly frustrated, and only the AF2 phase of the three magnetically ordered phases (AF1, AF2, AF3) is ferroelectric. The high frustration may thus allow a possibility to tune the magnetic structure by means of an electric field via magnetoelectric coupling. By using the pyroelectric current method, we measure the remnant ferroelectric polarization in MnWO4 upon application of a poling electric field via two different roadmaps. It is demonstrated that an electric field as low as 10 kV cm(-1) is sufficient to enhance the stability of a ferroelectric AF2 phase at the expense of a non-ferroelectric AF1 phase. This work suggests that electric field induced electrostatic energy, although small due to weak magnetically induced electric polarization, may effectively tune ferroelectric domain structures, and thus the magnetic structure of highly frustrated multiferroic materials.

19.
Sci Rep ; 4: 3984, 2014 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-24496324

RESUMO

One of the major breakthroughs associated with multiferroicity in recent years is the discovery of ferroelectricity generated by specific magnetic structures in some magnetic insulating oxides such as rare-earth manganites RMnO3 and RMn2O5. An unresolved issue is the small electric polarization. Relatively large electric polarization and strong magnetoelectric coupling have been found in those manganites of double magnetic ions: magnetic rare-earth R ion and Mn ion, due to the strong R-Mn (4f-3d) interactions. DyMn2O5 is a representative example. We unveil in this work the ferrielectric nature of DyMn2O5, in which the two ferroelectric sublattices with opposite electric polarizations constitute the ferrielectric state. One sublattice has its polarization generated by the symmetric exchange striction from the Mn-Mn interactions, while the polarization of the other sublattice is attributed to the symmetric exchange striction from the Dy-Mn interactions. We present detailed measurements on the electric polarization as a function of temperature, magnetic field, and measuring paths. The present experiments may be helpful for clarifying the puzzling issues on the multiferroicity in DyMn2O5 and other RMn2O5 multiferroics.

20.
J Mater Chem B ; 2(12): 1619-1625, 2014 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-32261389

RESUMO

The objective of this research is to investigate the plasma pharmacokinetics and bio-distribution of liposomal daunorubicin plus tamoxifen in breast cancer murine models through intravenous administration. Daunorubicin and tamoxifen plasma levels in pharmacokinetics studies were determined using HPLC. Biodistributions of various carriers loaded with a cyanine dye (cy7) were evaluated using in vivo imaging. After administration, free daunorubicin and tamoxifen were rapidly cleared out from the blood following a two-compartment kinetic model. The clearances and AUC (0-∞) of daunorubicin were (means ± SD): 0.028 ± 0.005 L h-1 kg-1 and 367.489 ± 56.979 µg mL-1 h-1 (liposomes), and 2.235 ± 0.347 L h-1 kg-1 and 4.546 ± 0.704 µg mL-1 h-1 (free drug). By ex vivo imaging 24 h after injection, the fluorescence intensity of liposomal cy7 plus tamoxifen in tumor region was obviously higher than that of free liposomal cy7. In conclusion, tamoxifen can improve pharmacokinetics profile of liposomal daunorubicin with enhanced therapy for breast cancer.

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