16 research outputs found

    Genetic and Molecular Characterization of a New EMS-Induced Mutant without the Third Glucose Moiety at the C-3 Sugar Chain of Saponin in Glycine max (L.) Merr.

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    Saponin, a secondary metabolite, is produced by various plant species, including soybean (Glycine max (L.) Merr.). Soybeans synthesize triterpenoid saponins, which are classified by their aglycone structure and sugar chain composition. Here, we characterized an ethyl methanesulfonate-induced mutant, PE1539, without saponin and with a glucose moiety at the third position of the C-3 sugar chain. The saponin phenotype of PE1539 is described by the accumulation of Ab-gamma g saponin and deficiency of Ab-alpha g saponin and DDMP-alpha g saponin, similar to a previously reported sg-3 mutant in soybean. Genetic analysis showed that the saponin phenotype of PE1539 is controlled by a recessive mutation. We mapped the gene responsible for the phenotype of PE1539 and the mapped region included Sg-3 (Glyma.10G104700). Further analysis of Sg-3 in PE1539 using DNA sequencing revealed a single-nucleotide substitution in the exon (G804A), resulting in a premature stop codon; thus, PE1539 produced a PSPG box-truncated protein. Saponin phenotype analysis of the F-2 population-from a cross between wild-type Uram and PE1539-showed that the phenotype of saponin was cosegregated with the genotype of Sg 3. Quantitative real-time PCR showed reduced expression of Sg-3 in PE1539 cells. Together, our data indicate that the saponin phenotype of PE1539 results from a mutation in Sg-3

    The relationship between mental representations of self and social evaluation: Examining the validity and usefulness of visual proxies of self-image.

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    Reverse correlation (RC) method has been recently used to visualize mental representations of self. Previous studies have mainly examined the relationship between psychological aspects measured by self-reports and classification images of self (self-CIs), which are visual proxies of self-image generated through the RC method. In Experiment 1 (N = 118), to extend the validity of self-CIs, we employed social evaluation on top of self-reports as criterion variables and examined the relationship between self-CIs and social evaluation provided by clinical psychologists. Experiment 1 revealed that the valence ratings of self-CIs evaluated by independent raters predicted social evaluation after controlling for the effects of self-reported self-esteem and extraversion. Furthermore, in Experiment 2 (N = 127), we examined whether a computational scoring method - a method to assess self-CIs without employing independent raters - could be applied to evaluate the valence of participants self-CIs. Experiment 2 found that the computational scores of self-CIs were comparable to independent valence ratings of self-CIs. We provide evidence that self-CIs can add independent information to self-reports in predicting social evaluation. We also suggest that the computational scoring method can complement the independent rating process of self-CIs. Overall, our findings reveal that self-CIs are a valid and useful tool to examine self-image more profoundly

    Design of a circular dual-loop antenna for a GPS array element using an extended cavity structure

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    This article proposes a circular dual-loop antenna for a very small Global Positioning System array with an extended cavity structure. The antenna element consists of lower and upper circular loops printed on a high-dielectric ceramic substrate and an extended cavity structure above the ground plane to improve the isolation characteristic. To demonstrate the suitability of the proposed antenna, antenna characteristics are measured in a full-anechoic chamber, and its performances such as bore-sight gain, mutual coupling, and near-field as a function of extended cavity height are analyzed. The results confirm that the proposed antenna structure can minimize the gain degradation by improving the isolation characteristic and is therefore suitable for use in very small arrays

    Online learning performance and engagement during the COVID-19 pandemic: Application of the dual-continua model of mental health.

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    The COVID-19 pandemic has led to an abrupt transition from face-to-face learning to online learning, which has also affected the mental health of college students. In this study, we examined the relationship between students adjustment to online learning and their mental health by using the Dual-Continua Model. The model assumes that mental disorder and mental well-being are related yet distinct factors of mental health. For this purpose, 2,933 college students completed an online survey around the beginning of the Fall semester of 2020 (N = 1,724) and the Spring semester of 2021 (N = 1,209). We assessed participants mental well-being, mental disorders, and academic distress by means of the online survey. In addition, we incorporated grades and log data accumulated in the Learning Management System (LMS) as objective learning indicators of academic achievement and engagement in online learning. Results revealed that two dimensions of mental health (i.e., mental well-being and mental disorder) were independently associated with all objective and subjective online learning indicators. Specifically, languishing (i.e., low levels of mental well-being) was negatively associated with student engagement derived from LMS log data and academic achievement and was positively associated with self-reported academic distress even after we controlled for the effects of mental disorder. In addition, mental disorder was negatively related to student engagement and academic achievement and was positively related to academic distress even after we controlled for the effects of mental well-being. These results remained notable even when we controlled for the effects of sociodemographic variables. Our findings imply that applying the Dual-Continua Model contributes to a better understanding of the relationship between college students mental health and their adaptation to online learning. We suggest that it is imperative to implement university-wide interventions that promote mental well-being and alleviate psychological symptoms for students successful adjustment to online learning

    Development and validation of COVID-19 Impact Scale.

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    BACKGROUND: As the COVID-19 (Coronavirus disease 2019) pandemic is prolonged, psychological responses to the pandemic have changed, and a new scale to reflect these changes needs to be developed. In this study, we attempt to develop and validate the COVID-19 Impact Scale (CIS) to measure the psychological stress responses of the COVID-19 pandemic, including emotional responses and difficulty with activities of daily living. METHODS: We recruited 2152 participants. Participants completed the CIS, the Fear of COVID-19 Scale (FCV-19S), and other mental health related measures. The factor structure, reliability, and validity of the CIS were analyzed. In addition, the validity of the scale was confirmed by its relationships to the existing measures assessing fear of COVID-19, depression, anxiety, subjective well-being, and suicidal ideation. RESULTS: Using exploratory factor analysis (N1 = 1076), we derived a one-factor structure. In confirmatory factor analysis (N2 = 1076), the one-factor model showed good to excellent fitness. The CIS was positively correlated with depression, anxiety, suicidal ideation, fear of COVID-19 and negatively correlated with subjective well-being. The FCV-19S did not show significant correlations with subjective well-being or suicidal ideation, and FCV-19Ss explanatory powers on depression and anxiety were lower than those of the CIS. CONCLUSIONS: These results support that the CIS is a valid assessment of emotional problems and deterioration of the quality of life caused by the COVID-19 pandemic. Finally, the limitations of this study and future research directions are discussed

    Development and validation of COVID-19 Impact Scale

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    Biochemical reprogramming of tumors for active modulation of receptor-mediated nanomaterial delivery

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    Here we report that reactive oxygen species (ROS) can reprogram cancer cells to increase the expression of specific receptors and modulate the delivery of nanomaterials. Gold and gamma-polyglutamic acid (gamma-PGA) hybrid nanoparticles (PGANP) were prepared via a facile single-step process. Gold nanoclusters in PGANP were dispersed within the tangled gamma-PGA matrix of the nanoparticles. The condensed assembly of gold nanoclusters in gamma-PGA matrix enabled the interparticle plasmon coupling effect, which lacks in single gold nanoparticles. Compared with gold nanoparticles of the similar sizes, PGANP showed significantly higher absorbance at near infrared (NIR) wavelength and light-to-heat converting ratios, resulting in greater temperature increase upon NIR light irradiation. Pretreatment of HeLa cancer cells with methylene blue (MB) generated reactive oxygen species. The ROS reprogrammed the cancer cells to express higher cell membrane levels of gamma glutamyl transferase (GGT), which is known to bind to gamma-PGA of PGANP. MB pretreatment significantly enhanced delivery of PGANP to cancer cells. Cancer cells internalized PGANP to a greater extent and, were highly susceptible to irradiation with NIR light, which reduced cell viability to near zero. In vivo, MB pretreatment of HeLa xenograft mice increased the expression of GGT in tumor tissues. In mice pretreated with MB and exposed to NIR irradiation, PGANP treatment resulted in complete tumor ablation. The strategy of actively reprogramming tumor membrane levels of target receptors could be widely applied to overcome the heterogeneity of cancer cells. Although we used interparticle plasmon coupling effect-based PGANP for proving the concept of receptor-modulated delivery, this strategy could be broadly applicable to the active modulation of the receptor-mediated delivery of anticancer nanomaterials.Y

    Effects of Saffron Extract (Affron<sup>®</sup>) with 100 mg/kg and 200 mg/kg on Hypothalamic–Pituitary–Adrenal Axis and Stress Resilience in Chronic Mild Stress-Induced Depression in Wistar Rats

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    Stress-related symptoms are a global concern, impacting millions of individuals, yet effective and safe treatments remain scarce. Although multiple studies have highlighted the stress- alleviating properties of saffron extract, the underlying mechanisms remain unclear. This study employs the unpredictable chronic mild stress (CMS) animal model to investigate the impact of a standardized saffron extract, Affron® (AFN), on hypothalamic–pituitary–adrenal (HPA) axis regulation and neuroplasticity in Wistar rats following repeated oral administration. The research evaluates AFN’s effects on various stress-related parameters, including hypothalamic gene expression, stress hormone levels, and the sucrose preference test. In animals subjected to continuous unpredictable CMS, repetitive administration of AFN at doses of 100 mg/kg and 200 mg/kg effectively normalized HPA axis dysregulation and enhanced neuroplasticity. Increased concentrations of AFN demonstrated greater efficacy. Following AFN oral administration, adrenocorticotropic and corticosterone hormone levels exhibited significant or nearly significant reductions in comparison to subjects exposed to stress only. These changes align with the alleviation of stress and the normalization of the HPA axis. These findings elucidate AFN’s role in stress mitigation, affirm its health benefits, validate its potential as a treatment for stress-related symptoms, confirm its physiological effectiveness, and emphasize its therapeutic promise
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