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1.
Ultrason Sonochem ; : 104875, 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31796329

RESUMO

Episodic release of bioactive compounds is often necessary for appropriate biological effects under specific physiological conditions. Here, we aimed to develop an injectable, biocompatible, and thermosensitive hydrogel system for ultrasound (US)-triggered drug release. An mPEG-PLGA-BOX block copolymer hydrogel was synthesized. The viscosity of 15 wt% hydrogel is 0.03 Pa*s at 25 °C (liquid form) and 34.37 Pa*s at 37 °C (gel form). Baseline and US-responsive in vitro release profile of a small molecule (doxorubicin) and that of a large molecule (FITC-dextran), from the hydrogel, was tested. A constant baseline release was observed in vitro for 7 d. When triggered by US (1 MHz, continuous, 0.4 W/cm2), the release rate increased by approximately 70 times. Without US, the release rate returned to baseline. Baseline and US-responsive in vivo release profile of doxorubicin was tested by subcutaneous injection in the back of mice and rats. Following injection into the subcutaneous layer, in vivo results also suggested that the hydrogels remained in situ and provided a steady release for at least 7 d; in the presence of the US-trigger, in vivo release from the hydrogel increased by approximately 10 times. Therefore, the mPEG-PLGA-BOX block copolymer hydrogel may serve as an injectable, biocompatible, and thermosensitive hydrogel system that is applicable for US-triggered drug release.

2.
Sci Rep ; 9(1): 15614, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31666607

RESUMO

Traumatic cerebral contusion and intracerebral hemorrhages (ICH) commonly result from traumatic brain injury and are associated with high morbidity and mortality rates. Current animal models require craniotomy and provide less control over injury severity. This study proposes a highly reproducible and controllable traumatic contusion and ICH model using non-invasive extracorporeal shockwaves (ESWs). Rat heads were exposed to ESWs generated by an off-the-shelf clinical device plus intravenous injection of microbubbles to enhance the cavitation effect for non-invasive induction of injury. Results indicate that injury severity can be effectively adjusted by using different ESW parameters. Moreover, the location or depth of injury can be purposefully determined by changing the focus of the concave ESW probe. Traumatic contusion and ICH were confirmed by H&E staining. Interestingly, the numbers of TUNEL-positive cells (apoptotic cell death) peaked one day after ESW exposure, while Iba1-positive cells (reactive microglia) and GFAP-positive cells (astrogliosis) respectively peaked seven and fourteen days after exposure. Cytokine assay showed significantly increased expressions of IL-1ß, IL-6, and TNF-α. The extent of brain edema was characterized with magnetic resonance imaging. Conclusively, the proposed non-invasive and highly reproducible preclinical model effectively simulates the mechanism of closed head injury and provides focused traumatic contusion and ICH.

3.
Hum Brain Mapp ; 40(11): 3192-3202, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-30941797

RESUMO

Nonrapid eye movement (NREM) sleep is associated with fading consciousness in humans. Recent neuroimaging studies have demonstrated the spatiotemporal alterations of the brain functional connectivity (FC) in NREM sleep, suggesting the changes of information integration in the sleeping brain. However, the common stationarity assumption in FC does not satisfactorily explain the dynamic process of information integration during sleep. The dynamic FC (dFC) across brain networks is speculated to better reflect the time-varying information propagation during sleep. Accordingly, we conducted simultaneous EEG-fMRI recordings involving 12 healthy men during sleep and observed dFC across sleep stages using the sliding-window approach. We divided dFC into two aspects: mean dFC (dFCmean ) and variance dFC (dFCvar ). A high dFCmean indicates stable brain network integrity, whereas a high dFCvar indicates instability of information transfer within and between functional networks. For the network-based dFC, the dFCvar were negatively correlated with the dFCmean across the waking and three NREM sleep stages. As sleep deepened, the dFCmean decreased (N0~N1 > N2 > N3), whereas the dFCvar peaked during the N2 stage (N0~N1 < N3 < N2). The highest dFCvar during the N2 stage indicated the unstable synchronizations across the entire brain. In the N3 stage, the overall disrupted network integration was observed through the lowest dFCmean and elevated dFCvar, compared with N0 and N1. Conclusively, when the network specificity (dFCmean ) breaks down, the consciousness dissipates with increasing variability of information exchange (dFCvar ).

4.
Biosens Bioelectron ; 131: 53-59, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30826650

RESUMO

This investigation develops a label-free and reagentless aptasensor, based on a capacitive transducer with simple face-to-face electrode pairs. The electrode pairs of the transducer are composed of a gold electrode and an indium tin oxide film with micrometer separation with a double-side polyethylene terephthalate tape. Aptamers and 1-dodecanethiol are modified to form a self-assembled monolayer (SAM) on the gold electrode surfaces, and function as bio-recognition elements and preventers of non-specific protein binding, respectively. Electrochemical characterization results indicate that the SAM also forms an effective insulating layer, which is sufficient for capacitive sensing. The feasibility of the capacitive biosensor is validated using thrombin as a model analyte. The ultra-small value changes of capacitance originating from thrombin binding with the aptamers modified on the biosensor were measured with a home-made capacitance measuring circuit based on switched capacitor (SC) technology. The developed biosensor has detection limits of 1 pM and 10 pM of thrombin in phosphate buffered saline and mimic serum solution, respectively. The linear range for thrombin detection in human serum solution is from 10 pM to 1 µM, with a regression coefficient of 0.98. Additionally, the proposed aptasensor does not have significant levels of non-specific binding of bovine serum albumin and human serum albumin. Accordingly, the combination of SC and SAM bringing capacitive transduction at the forefront of ultrasensitive label-free and reagentless biosensing devices, particularly for point-of-care clinical analysis, which adopts small numbers of biological samples with low analyte concentrations.


Assuntos
Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais , Técnicas Eletroquímicas , Trombina/isolamento & purificação , Aptâmeros de Nucleotídeos/genética , Eletrodos , Ouro/química , Humanos , Limite de Detecção , Trombina/química , Trombina/genética , Compostos de Estanho/química
5.
Int J Biometeorol ; 63(2): 259-268, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30680621

RESUMO

Dengue is one of the most rapidly spreading mosquito-borne viral diseases in the world. An increase in the incidence of dengue is commonly thought to be a consequence of variability of weather conditions. Taiwan, which straddles the Tropic of Cancer, is an excellent place to study the relationship between weather conditions and dengue fever cases since the island forms an isolated geographic environment. Therefore, clarifying the association between extreme weather conditions and annual dengue incidence is one of important issues for epidemic early warning. In this paper, we develop a Poisson regression model with extreme weather parameters for prediction of annual dengue incidence. A leave-one-out method is used to evaluate the performance of predicting dengue incidence. Our results indicate that dengue transmission has a positive relationship with the minimum temperature predictors during the early summer while a negative relationship with all the maximum 24-h rainfall predictors during the early epidemic phase of dengue outbreaks. Our findings provide a better understanding of the relationships between extreme weather and annual trends in dengue cases in Taiwan and it could have important implications for dengue forecasts in surrounding areas with similar meteorological conditions.


Assuntos
Dengue/epidemiologia , Modelos Estatísticos , Tempo (Meteorologia) , Clima , Previsões , Humanos , Incidência , Distribuição de Poisson , Análise de Regressão , Taiwan/epidemiologia
6.
Mon Not R Astron Soc ; 480(2): 1666-1675, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30581240

RESUMO

Using high-resolution simulations from the FIRE-2 (Feedback In Realistic Environments) project, we study the effects of discreteness in stellar feedback processes on the evolution of galaxies and the properties of the interstellar medium (ISM). We specifically consider the discretization of supernovae (SNe), including hypernovae (HNe), and sampling the initial mass function (IMF). We study these processes in cosmological simulations of dwarf galaxies with z = 0 stellar masses M * ~ 104-3 × 106 M⊙ (halo masses ~109-1010 M⊙). We show that the discrete nature of individual SNe (as opposed to a model in which their energy/momentum deposition is continuous overtime, similar to stellar winds) is crucial in generating a reasonable ISM structure and galactic winds and in regulating dwarf stellar masses. However, once SNe are discretized, accounting for the effects of IMF sampling on continuous mechanisms such as radiative feedback and stellar mass-loss (as opposed to adopting IMF-averaged rates) has weak effects on galaxy-scale properties. We also consider the effects of rare HNe events with energies ~1053 erg. The effects of HNe are similar to the effects of clustered explosions of SNe - which are already captured in our default simulation setup - and do not quench star formation (provided that the HNe do not dominate the total SNe energy budget), which suggests that HNe yield products should be observable in ultra-faint dwarfs today.

7.
Sci Rep ; 8(1): 2218, 2018 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-29396523

RESUMO

Despite extensive efforts in recent years, the blood-brain barrier (BBB) remains a significant obstacle for drug delivery. This study proposes using a clinical extracorporeal shockwave instrument to open the BBB, combined with a laser assisted bi-axial locating platform to achieve non-invasive, controllable-focus and reversible BBB opening in the brains of rats. Under shockwave treatment with an intensity level of 5 (P-9.79 MPa, energy flux density (EFD) 0.21 mJ/mm2) and a pulse repetition frequency of 5 Hz, the BBB could be opened after 50 shocks without the use of an ultrasound contrast agent. With the proposed method, the BBB opening can be precisely controlled in terms of depth, size and location. Moreover, a shockwave based gene transfection was demonstrated using a luciferase gene.


Assuntos
Barreira Hematoencefálica/efeitos da radiação , Tratamento por Ondas de Choque Extracorpóreas/métodos , Terapia Genética/métodos , Ondas de Choque de Alta Energia , Transfecção , Animais , Encéfalo/efeitos da radiação , Genes Reporter , Luciferases/análise , Luciferases/genética , Ratos
8.
Bioelectrochemistry ; 118: 31-37, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28708990

RESUMO

The efficacy of genomic medicine depends on gene transfer efficiency. In this area, electroporation has been found to be a highly promising method for physical gene transfer. However, electroporation raises issues related to electrical safety, tissue damage, and the number of required wounds. Concentric-type needle electrodes seek to address these issues by using a lower bias (10V), a single wound, fewer processing steps, and a smaller working area (≈10mm3), thus offering greater accuracy and precision. Moreover, the needle can be arrayed to simultaneously treat several target regions. This paper proposes a novel method using concentric-type needle electrodes to improve the efficacy of genomic medicine in terms of electrical safety, human factor and usability engineering.


Assuntos
Eletroporação/instrumentação , Agulhas , Animais , Eletrodos , Técnicas de Transferência de Genes/instrumentação , Camundongos , Peixe-Zebra/genética
9.
Stress Health ; 33(3): 233-243, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27509839

RESUMO

Greater risk of post-traumatic stress disorder (PTSD) is seen in individuals exposed to interpersonal traumatic events. Based on an attachment perspective, interpersonal trauma exposure may activate one's attachment insecurity system and disrupt affect, behaviour and interpersonal function, which may in turn create more difficulties to cope with interpersonal traumas and exacerbate PTSD symptomatology. The present study examined whether attachment anxiety relative to attachment avoidance would be a stronger predictor of greater PTSD symptoms following interpersonal traumas versus impersonal traumas in a Taiwanese sample. One hundred and sixty-two trauma-exposed Taiwanese young adults completed the measures of symptoms of depression, anxiety and PTSD, and attachment anxiety and attachment avoidance. In this Taiwanese study, higher attachment anxiety was observed in individuals who were exposed to interpersonal traumas. The interpersonal trauma group reported greater PTSD symptoms than did the impersonal trauma group. Specifically, after controlling for age, occurrence of trauma and distress of trauma, attachment anxiety, but not attachment avoidance, predicted more PTSD total severity and avoidance symptoms in the interpersonal trauma group. The findings may be pertinent to attachment anxiety-related hyperactivating strategies, as well as specific cultural values and a forbearance strategy applied to regulate traumatic distress in a collectivist society. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Transtornos de Ansiedade/fisiopatologia , Ansiedade/fisiopatologia , Relações Interpessoais , Acontecimentos que Mudam a Vida , Apego ao Objeto , Transtornos de Estresse Pós-Traumáticos/fisiopatologia , Adolescente , Adulto , Ansiedade/epidemiologia , Ansiedade/etiologia , Transtornos de Ansiedade/epidemiologia , Transtornos de Ansiedade/etiologia , Depressão/epidemiologia , Depressão/fisiopatologia , Humanos , Índice de Gravidade de Doença , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Transtornos de Estresse Pós-Traumáticos/etiologia , Taiwan/epidemiologia , Adulto Jovem
10.
Biometrics ; 72(4): 1226-1234, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-26953633

RESUMO

In applying scan statistics for public health research, it would be valuable to develop a detection method for multiple clusters that accommodates spatial correlation and covariate effects in an integrated model. In this article, we connect the concepts of the likelihood ratio (LR) scan statistic and the quasi-likelihood (QL) scan statistic to provide a series of detection procedures sufficiently flexible to apply to clusters of arbitrary shape. First, we use an independent scan model for detection of clusters and then a variogram tool to examine the existence of spatial correlation and regional variation based on residuals of the independent scan model. When the estimate of regional variation is significantly different from zero, a mixed QL estimating equation is developed to estimate coefficients of geographic clusters and covariates. We use the Benjamini-Hochberg procedure (1995) to find a threshold for p-values to address the multiple testing problem. A quasi-deviance criterion is used to regroup the estimated clusters to find geographic clusters with arbitrary shapes. We conduct simulations to compare the performance of the proposed method with other scan statistics. For illustration, the method is applied to enterovirus data from Taiwan.


Assuntos
Análise por Conglomerados , Monitoramento Epidemiológico , Modelos Estatísticos , Saúde Pública/estatística & dados numéricos , Biometria/métodos , Simulação por Computador , Surtos de Doenças/estatística & dados numéricos , Infecções por Enterovirus/epidemiologia , Humanos , Probabilidade , Taiwan/epidemiologia , Topografia Médica
11.
Cephalalgia ; 36(14): 1324-1333, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26853805

RESUMO

OBJECTIVE: The objective of this article is to investigate the neurological substrates associated with medication overuse (MO) in patients with chronic migraine (CM). METHODS: We recruited age- and sex-matched CM patients with MO (CMwMO), CM patients without MO (CMwoMO), and healthy controls (HCs). Magnetic resonance T1-weighted images were processed by voxel-based morphometry, and the findings were correlated with clinical variables and treatment responses. RESULTS: A total of 66 patients with CM (half with MO) and 33 HCs completed the study. Patients with CMwMO compared to the patients with CMwoMO showed gray matter volume (GMV) decrease in the orbitofrontal cortex and left middle occipital gyrus as well as GMV increase in the left temporal pole/parahippocampus. The GMV changes explained 31.1% variance of the analgesics use frequency. The patients who responded to treatment had greater GMV in the orbitofrontal cortex (p = 0.028). Patients with CM (with and without MO), compared with HCs, had decreased GMV at multiple brain areas including the frontal, temporal and occipital lobes, precuneus and cerebellum. CONCLUSIONS: Our study showed GMV changes in CMwMO patients compared to the CMwoMO patients. These three cerebral regions accounted for significant variance in analgesics use frequency. Moreover, the GMV of the orbitofrontal cortex was predictive of the response to MO treatments.


Assuntos
Substância Cinzenta/diagnóstico por imagem , Transtornos da Cefaleia Secundários/diagnóstico por imagem , Imagem por Ressonância Magnética/tendências , Transtornos de Enxaqueca/diagnóstico por imagem , Uso Excessivo de Medicamentos Prescritos/tendências , Adulto , Doença Crônica , Feminino , Substância Cinzenta/metabolismo , Transtornos da Cefaleia Secundários/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos de Enxaqueca/metabolismo
12.
Sci Rep ; 5: 9804, 2015 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-25913508

RESUMO

Controlling plant viruses by genetic engineering, including the globally important Papaya ringspot virus (PRSV), mainly involves coat protein (CP) gene mediated resistance via post-transcriptional gene silencing (PTGS). However, the breakdown of single- or double-virus resistance in CP-gene-transgenic papaya by more virulent PRSV strains has been noted in repeated field trials. Recombination analysis revealed that the gene silencing suppressor HC-Pro or CP of the virulent PRSV strain 5-19 is responsible for overcoming CP-transgenic resistance in a sequence-homology-independent manner. Transient expression assays using agro-infiltration in Nicotiana benthamiana plants indicated that 5-19 HC-Pro exhibits stronger PTGS suppression than the transgene donor strain. To disarm the suppressor from the virulent strain, transgenic papaya lines were generated carrying untranslatable 5-19 HC-Pro, which conferred complete resistance to 5-19 and other geographic PRSV strains. Our study suggested the potential risk of the emergence of more virulent virus strains, spurred by the deployment of CP-gene-transgenic crops, and provides a strategy to combat such strains.


Assuntos
Carica/genética , Carica/virologia , Vírus de Plantas/patogenicidade , Plantas Geneticamente Modificadas/virologia , Transgenes/genética , Virulência/genética , Proteínas do Capsídeo/genética , Doenças das Plantas/genética , Doenças das Plantas/prevenção & controle , Doenças das Plantas/virologia , Plantas Geneticamente Modificadas/genética , Homologia de Sequência do Ácido Nucleico
13.
Mol Plant Microbe Interact ; 27(9): 944-55, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24804808

RESUMO

Cross-protection triggered by a mild strain of virus acts as a prophylaxis to prevent subsequent infections by related viruses in plants; however, the underling mechanisms are not fully understood. Through mutagenesis, we isolated a mutant strain of Turnip mosaic virus (TuMV), named Tu-GK, that contains an Arg182Lys substitution in helper component-proteinase (HC-Pro(K)) that confers complete cross-protection against infection by a severe strain of TuMV in Nicotiana benthamiana, Arabidopsis thaliana Col-0, and the Arabidopsis dcl2-4/dcl4-1 double mutant defective in DICER-like ribonuclease (DCL)2/DCL4-mediated silencing. Our analyses showed that HC-Pro(K) loses the ability to interfere with microRNA pathways, although it retains a partial capability for RNA silencing suppression triggered by DCL. We further showed that Tu-GK infection triggers strong salicylic acid (SA)-dependent and SA-independent innate immunity responses. Our data suggest that DCL2/4-dependent and -independent RNA silencing pathways are involved, and may crosstalk with basal innate immunity pathways, in host defense and in cross-protection.


Assuntos
Proteínas de Arabidopsis/genética , Proteínas de Ciclo Celular/genética , Proteção Cruzada , Cisteína Endopeptidases/genética , Doenças das Plantas/imunologia , Potyvirus/genética , Ribonuclease III/genética , Proteínas Virais/genética , Motivos de Aminoácidos , Substituição de Aminoácidos , Arabidopsis/imunologia , Arabidopsis/virologia , Proteínas de Arabidopsis/metabolismo , Proteínas de Ciclo Celular/metabolismo , Cisteína Endopeptidases/metabolismo , Regulação da Expressão Gênica de Plantas , Sequenciamento de Nucleotídeos em Larga Escala , MicroRNAs/genética , Modelos Biológicos , Mutação , Doenças das Plantas/virologia , Folhas de Planta/imunologia , Folhas de Planta/virologia , Plantas Geneticamente Modificadas , Potyvirus/fisiologia , Interferência de RNA , Ribonuclease III/metabolismo , Ácido Salicílico/metabolismo , Plântula/imunologia , Plântula/virologia , Análise de Sequência de RNA , Tabaco/imunologia , Tabaco/virologia , Proteínas Virais/metabolismo
14.
Mar Drugs ; 11(10): 3902-25, 2013 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-24132179

RESUMO

Deep ocean water (DOW) has, in previous studies, been found to be a novel anti-obesity drink and useful in raising Monascus-produced monascin and ankaflavin levels. This may resolve the limited anti-obesity ability of red mold dioscorea (RMD) known as the Monascus purpureus-fermented Disocorea batatas. This study aims to compare the anti-obesity effect of DOW-cultured RMD (DOW-RMD) and ultra-pure water-cultured RMD (UPW-RMD) in rats fed on a high fat diet. Moreover, the effect of ions composition of DOW and DOW-influenced functional metabolites change of RMD on the differentiation and lipogenesis regulation were investigated using 3T3-L1 pre-adipocytes. In the animal test, compared to UPW-RMD, DOW-RMD possessed better ability to inhibit increases in weight gain, and better feed efficiency, body-fat pad and cross-sectional area of adipocytes. In the cell test, the anti-obesity abilities of DOW-RMD in inhibiting PPARγ and C/EBPα expression in differentiation and lipoprotein lipase activity in lipogenesis were contributed to by the DOW-increased monascin and ankaflavin levels and the ions of DOW, respectively.


Assuntos
Fármacos Antiobesidade/farmacologia , Dioscorea/metabolismo , Fungos/metabolismo , Monascus/metabolismo , Obesidade/tratamento farmacológico , Água/metabolismo , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Animais , Fermentação , Flavinas/metabolismo , Compostos Heterocíclicos com 3 Anéis/metabolismo , Lipídeos/sangue , Masculino , Obesidade/sangue , Ratos , Ratos Sprague-Dawley , Água do Mar
15.
Artigo em Inglês | MEDLINE | ID: mdl-23840269

RESUMO

Drug resistance and tumor recurrence are major obstacles in treating lung cancer patients. Accumulating evidence considers lung cancer stem cells (CSCs) as the major contributor to these clinical challenges. Agents that can target lung CSCs could potentially provide a more effective treatment than traditional chemotherapy. Here, we utilized the side-population (SP) method to isolate lung CSCs from A549 and PC-9 cell lines. Subsequently, a high throughput platform, connectivity maps (CMAPs), was used to identify potential anti-CSC agents. An antibiotic, antimycin A (AMA), was identified as a top candidate. SP A549 cells exhibited an elevated stemness profile, including Nanog, ß -catenin, Sox2, and CD133, and increased self-renewal ability. AMA treatment was found to suppress ß -catenin signaling components and tumor sphere formation. Furthermore, AMA treatment decreased the proliferation of gefitinib-resistant PC-9/GR cells and percentage of SP population. AMA demonstrated synergistic suppression of PC-9/GR cell viability when combined with gefitinib. Finally, AMA treatment suppressed tumorigenesis in mice inoculated with A549 SP cells. Collectively, we have identified AMA using CMAP as a novel antilung CSC agent, which acts to downregulate ß -catenin signaling. The combination of AMA and targeted therapeutic agents could be considered for overcoming drug resistance and relapse in lung cancer patients.

16.
Risk Anal ; 32(9): 1535-46, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22300232

RESUMO

This study explored how individuals in Taiwan perceive the risk of earthquake and the relationship of past earthquake experience and gender to risk perception. Participants (n= 1,405), including earthquake survivors and those in the general population without prior direct earthquake exposure, were selected and interviewed through a computer-assisted telephone interviewing procedure using a random sampling and stratification method covering all 24 regions of Taiwan. A factor analysis of the interview data yielded a two-factor structure of risk perception in regard to earthquake. The first factor, "personal impact," encompassed perception of threat and fear related to earthquakes. The second factor, "controllability," encompassed a sense of efficacy of self-protection in regard to earthquakes. The findings indicated prior earthquake survivors and females reported higher scores on the personal impact factor than males and those with no prior direct earthquake experience, although there were no group differences on the controllability factor. The findings support that risk perception has multiple components, and suggest that past experience (survivor status) and gender (female) affect the perception of risk. Exploration of potential contributions of other demographic factors such as age, education, and marital status to personal impact, especially for females and survivors, is discussed. Future research on and intervention program with regard to risk perception are suggested accordingly.


Assuntos
Terremotos , Percepção , Medição de Risco , Fatores Sexuais , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Taiwan
17.
Mol Plant Pathol ; 13(3): 303-17, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21929564

RESUMO

MicroRNAs (miRNAs) regulate the abundance of target mRNAs by guiding cleavage at sequence complementary regions. In this study, artificial miRNAs (amiRNAs) targeting conserved motifs of the L (replicase) gene of Watermelon silver mottle virus (WSMoV) were constructed using Arabidopsis pre-miRNA159a as the backbone. The constructs included six single amiRNAs targeting motifs A, B1, B2, C, D of E, and two triple amiRNAs targeting motifs AB1E or B2DC. Processing of pre-amiRNAs was confirmed by agro-infiltration, and transgenic Nicotiana benthamiana plants expressing each amiRNA were generated. Single amiRNA transgenic lines expressing amiR-LB2 or amiR-LD showed resistance to WSMoV by delaying symptom development. Triple amiRNA lines expressing amiR-LB2, amiR-LD and amiR-LC provided complete resistance against WSMoV, with no indication of infection 28 days after inoculation. Resistance levels were positively correlated with amiRNA expression levels in these single and triple amiRNA lines. The triple amiR-LAB1E line did not provide resistance to WSMoV. Similarly, the poorly expressed amiR-LC and amiR-LE lines did not provide resistance to WSMoV. The amiR-LA- and amiR-LB1-expressing lines were susceptible to WSMoV, and their additional susceptibility to the heterologous Turnip mosaic virus harbouring individual target sequences indicated that these two amiRNAs have no effect in vivo. Transgenic lines expressing amiR-LB2 exhibited delayed symptoms after challenge with Peanut bud necrosis virus having a single mismatch in the target site. Overall, our results indicate that two amiRNAs, amiR-LB2 and amiR-LD, of the six designed amiRNAs confer moderate resistance against WSMoV, and the triple construct including the two amiRNAs provides complete resistance.


Assuntos
MicroRNAs/genética , Plantas Geneticamente Modificadas/virologia , RNA Replicase/genética , RNA de Plantas/genética , RNA Viral/genética , Tabaco/virologia , Doenças das Plantas/virologia , Vírus de Plantas/genética , Vírus de Plantas/patogenicidade , Plantas Geneticamente Modificadas/genética , Tabaco/genética
18.
J Agric Food Chem ; 59(15): 8199-207, 2011 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-21732592

RESUMO

Red mold dioscorea (RMD) produced by Monascus sp. was proven to be a hypolipidemic functional food. Deep ocean water (DOW), that is, water obtained from over 200 m deep in the ocean, was found to promote the growth of fungus via its mineral richness. On the basis of the advantages, this study used 650 m DOW as the culture water to culture Monascus purpuresus NTU 568 and produce the DOW-RMD. The goal of this study is to compare the difference between DOW-RMD and reverse osmosis water-cultured RMD (ROW-RMD) on the hypolipidemic effect. Hyperlipidemic hamsters were fed a high-cholesterol diet and administered various doses of DOW-RMD or ROW-RMD for 8 weeks. After sacrifice, biochemical analyses in serum, liver, and feces were carried out. The results showed that DOW-RMD had a greater effect on lowering cholesterol levels and lipid peroxidation in serum and lipid plaque in heart aorta than ROW-RMD. However, DOW was likely to modulate the Monascus metabolite biosynthesis pathway toward the formation of hypolipidemic yellow pigments (such as monascin and ankaflavin) rather than red pigments and the mycotoxin citrinin. In addition, the DOW with higher Mg(2+) ion was proven to absorb into DOW-RMD; however, the accumulation of Mg(2+) ions should contribute a greater hypolipidemic effect to DOW-RMD. Comprehensively, the DOW-induced metabolism modulation and the ions of DOW were a benefit to the development of safe DOW-RMD with low citrinin levels and high hypolipidemic, antiatherosclerosis, and anti-fatty liver effects.


Assuntos
Dioscorea/microbiologia , Hiperlipidemias/tratamento farmacológico , Hipolipemiantes/metabolismo , Monascus/metabolismo , Preparações de Plantas/metabolismo , Animais , Cricetinae , Meios de Cultura/análise , Meios de Cultura/metabolismo , Dioscorea/metabolismo , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Fermentação , Humanos , Hiperlipidemias/metabolismo , Hipolipemiantes/administração & dosagem , Hipolipemiantes/efeitos adversos , Masculino , Mesocricetus , Monascus/crescimento & desenvolvimento , Preparações de Plantas/administração & dosagem , Preparações de Plantas/efeitos adversos , Água do Mar/análise , Água do Mar/microbiologia
19.
J Agric Food Chem ; 58(16): 9013-9, 2010 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-20666456

RESUMO

Monascus-fermented red mold dioscorea (RMD) has been proven to possess greater hypolipidemic effect than red mold rice (RMR) even though they include equal levels of cholesterol-lowering agent monacolin K. However, higher concentrations of yellow pigments (monascin and ankaflavin) were found in RMD than in RMR. In this study, purified monascin and ankaflavin were administered to hyperlipidemic hamsters for 8 weeks, respectively, to test whether these two compounds were novel hypolipidemic ingredients. In the statistical results, monascin and ankaflavin showed significant effect on lowering cholesterol, triglyceride, and low-density lipoprotein cholesterol levels in serum, as well as aorta lipid plaque (p < 0.05). Importantly, monascin and ankaflavin, unlike monacolin K, were able to perform up-regulation rather than down-regulation on high-density lipoprotein cholesterol (HDL-C) levels in serum. This finding not only explained why RMD showed greater hypolipidemic and HDL-C-raising effect than RMR but also proved that monascin and ankaflavin would act as novel and potent hypolipidemic ingredients.


Assuntos
HDL-Colesterol/sangue , Dioscorea/metabolismo , Flavinas/farmacologia , Compostos Heterocíclicos com 3 Anéis/farmacologia , Hipolipemiantes/farmacologia , Animais , Metabolismo Basal/efeitos dos fármacos , Densidade Óssea/efeitos dos fármacos , Cricetinae , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Mesocricetus
20.
Transgenic Res ; 19(4): 621-35, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19943109

RESUMO

Papaya production is seriously limited by Papaya ringspot virus (PRSV) worldwide and Papaya leaf-distortion mosaic virus (PLDMV) in Eastern Asia. An efficient transformation method for developing papaya lines with transgenic resistance to these viruses and commercially desirable traits, such as hermaphroditism, is crucial to shorten the breeding program for this fruit crop. In this investigation, an untranslatable chimeric construct pYP08 containing truncated PRSV coat protein (CP) and PLDMV CP genes coupled with the 3' untranslational region of PLDMV, was generated. Root segments from different portions of adventitious roots of in vitro multiple shoots of hermaphroditic plants of papaya cultivars 'Tainung No. 2', 'Sunrise', and 'Thailand' were cultured on induction medium for regeneration into somatic embryos. The highest frequency of somatic embryogenesis was from the root-tip segments of adventitious roots developed 2-4 weeks after rooting in perlite medium. After proliferation, embryogenic tissues derived from somatic embryos were wounded in liquid-phase by carborundum and transformed by Agrobacterium carrying pYP08. Similarly, another construct pBG-PLDMVstop containing untranslatable CP gene of PLDMV was also transferred to 'Sunrise' and 'Thailand', the parental cultivars of 'Tainung No. 2'. Among 107 transgenic lines regenerated from 349 root-tip segments, nine lines of Tainung No. 2 carrying YP08 were highly resistant to PRSV and PLDMV, and 9 lines (8 'Sunrise' and 1 'Thailand') carrying PLDMV CP highly resistant to PLDMV, by a mechanism of post-transcriptional gene silencing. The hermaphroditic characteristics of the transgenic lines were confirmed by PCR with sex-linked primers and phenotypes of flower and fruit. Our approach has generated transgenic resistance to both PRSV and PLDMV with commercially desirable characters and can significantly shorten the time-consuming breeding programs for the generation of elite cultivars of papaya hybrids.


Assuntos
Carica/genética , Carica/imunologia , Imunidade Inata/genética , Brotos de Planta/genética , Transformação Genética/fisiologia , Carica/embriologia , Carica/virologia , Células Cultivadas , Clonagem Molecular , Transtornos do Desenvolvimento Sexual/embriologia , Transtornos do Desenvolvimento Sexual/genética , Desenvolvimento Embrionário/genética , Desenvolvimento Embrionário/fisiologia , Vírus do Mosaico/imunologia , Doenças das Plantas/genética , Doenças das Plantas/imunologia , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Brotos de Planta/metabolismo , Plantas Geneticamente Modificadas , Sementes , Viroses/genética , Viroses/imunologia
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