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1.
Plant Physiol Biochem ; 115: 200-211, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28376412

RESUMEN

Molybdenum (Mo)-an essential element of plants-is involved in nitrogen (N) metabolism. Plants tend to accumulate more nitrate and show lower nitrogen use efficiency (NUE) under Mo-deficient conditions. Improving NUE in fruits reduces the negative effect of large applications of chemical fertilizer, but the mechanisms underlying how Mo enhances NUE remain unclear. We cultivated strawberry seedlings sprayed with 0, 67.5, 135, 168.75, or 202.5 g Mo·ha-1 in a non-soil culture system. The Mo concentration in every plant tissue analyzed increased gradually as Mo application level rose. Mo application affected iron, copper, and selenium adsorption in roots. Seedlings sprayed with 135 g Mo·ha-1 had a higher [15N] shoot:root (S:R) ratio, and 15NUE, and produced higher molybdate transporter type 1 (MOT1) expression levels in the roots and leaves. Seedlings sprayed with 135 g Mo·ha-1 also had relatively high nitrogen metabolic enzyme activities and up-regulated transcript levels of nitrate uptake genes (NRT1.1; NRT2.1) and nitrate-responsive genes. Furthermore, there was a significantly lower NO3- concentration in the leaves and roots, a higher NH4+ concentration in leaves, and a higher glutamine/glutamate (Gln/Glu) concentration at 135 g Mo·ha-1. Seedlings sprayed with 202.5 g Mo·ha-1 showed the opposite trend. Taken together, these results suggest that a 135 g Mo·ha-1 application was optimal because it enhanced NO3- transport from the roots to the shoots and increased NUE by mediating nitrogen metabolic enzyme activities, nitrate transport, and nitrate assimilation gene activities.


Asunto(s)
Fragaria/efectos de los fármacos , Molibdeno/toxicidad , Nitratos/metabolismo , Plantones/efectos de los fármacos , Cobre/metabolismo , Fragaria/metabolismo , Hierro/metabolismo , Isótopos de Nitrógeno , Plantones/metabolismo , Selenio/metabolismo
2.
Food Sci Nutr ; 4(6): 858-868, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27826436

RESUMEN

Strawberry fruits (cv. Benihoppe, Tochiotome, Sachinoka, and Guimeiren) were harvested and evaluated the flavor and nutritional parameters. By principal component analysis and hierarchical clustering analysis, differences were observed based on the volatile compounds composition, sugar and acid concentration, sweetness, and total soluble sugars/total organic acids of the four varieties. A total of 37, 48, 65, and 74 volatile compounds were identified and determined in cv. Benihoppe, Tochiotome, Sachinoka, and Guimeiren strawberry fruits extracted by head-space solid-phase microextraction (HS-SPME), respectively. Esters significantly dominated the chemical composition of the four varieties. Furaneol was detected in cultivars of Sachinoka and Guimeiren, but mesifuran was only found in cv. Tochiotome. Tochiotome and Sachinoka showed higher content of linalool and (E)-nerolidol. Sachinoka showed the highest content of total sugars and total acids. Guimeiren showed higher sweetness index than the other three cultivars. Firmness of Tochiotome was highest among all the varieties. The highest total soluble solids TSS value was found in cv. Sachinoka, followed by the Guimeiren and Tochiotome varieties. Sachinoka had the highest titratable acidity TA value. The content of ascorbic acid (AsA) of cv. Tochiotome was higher than the others, but there was no significant difference in cultivars of Benihoppe, Tochiotome, and Sachinoka. Fructose and glucose were the major sugars in all cultivars. Citric acid was the major organic acid in cv. Tochiotome, cv. Sachinoka, and cv. Guimeiren. Tochiotome had higher ratios of TSS/TA and total sugars/total organic acids than others, arising from its lower acid content. The order of the comprehensive evaluation score was Sachinoka>Guimeiren>Tochiotome>Benihoppe.

3.
Plant Physiol Biochem ; 104: 54-70, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27107182

RESUMEN

Dormancy is a biological characteristic developed to resist the cold conditions in winter. The bZIP transcription factors are present exclusively in eukaryotes and have been identified and classified in many species. bZIP proteins are known to regulate numerous biological processes, however, the role of bZIP in bud dodormancy has not been studied extensively. In total, 50 PpbZIP transcription factor-encoding genes were identified and categorized them into 10 groups (A-I and S). Similar intron/exon structures, additional conserved motifs, and DNA-binding site specificity supported our classification scheme. Additionally, chromosomal distribution and collinearity analyses suggested that expansion of the PpbZIP transcription factor family was due to segment/chromosomal duplications. We also predicted the dimerization properties based on characteristic features of the leucine zipper and classified PpbZIP proteins into 23 subfamilies. Furthermore, qRT-PCR results indicated that PpbZIPs genes may be involved in regulating dormancy. The same gene of different species might participate in different regulating networks through interactions with specific partners. Our expression profiling results complemented the microarray data, suggesting that co-expression patterns of bZIP transcription factors during dormancy differed among deciduous fruit trees. Our findings further clarify the molecular characteristics of the PpbZIP transcription factor family, including potential gene functions during dormancy. This information may facilitate further research on the evolutionary history and biological functions of bZIP proteins in peach and other rosaceae plants.


Asunto(s)
Flores/genética , Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Leucina Zippers/genética , Proteínas de Plantas/genética , Prunus persica/genética , Secuencia de Aminoácidos , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/química , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/genética , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/metabolismo , Sitios de Unión , Cromosomas de las Plantas/genética , Secuencia Conservada , ADN de Plantas/metabolismo , Intrones/genética , Familia de Multigenes , Motivos de Nucleótidos/genética , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Multimerización de Proteína , Sitios de Empalme de ARN/genética , Empalme del ARN/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Alineación de Secuencia
4.
Neuropsychology ; 30(6): 685-96, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27054437

RESUMEN

OBJECTIVE: Unwillingness to expend more effort to pursue high value rewards has been associated with motivational anhedonia in schizophrenia (SCZ) and abnormal dopamine activity in the nucleus accumbens (NAcc). The authors hypothesized that dysfunction of the NAcc and the associated forebrain regions are involved in the impaired effort expenditure decision-making of SCZ. METHOD: A 2 (reward magnitude: low vs. high) × 3 (probability: 20% vs. 50% vs. 80%) event-related fMRI design in the effort-expenditure for reward task (EEfRT) was used to examine the neural response of 23 SCZ patients and 23 demographically matched control participants when the participants made effort expenditure decisions to pursue uncertain rewards. RESULTS: SCZ patients were significantly less likely to expend high level of effort in the medium (50%) and high (80%) probability conditions than healthy controls. The neural response in the NAcc, the posterior cingulate gyrus and the left medial frontal gyrus in SCZ patients were weaker than healthy controls and did not linearly increase with an increase in reward magnitude and probability. Moreover, NAcc activity was positively correlated with the willingness to expend high-level effort and concrete consummatory pleasure experience. CONCLUSION: NAcc and posterior cingulate dysfunctions in SCZ patients may be involved in their impaired effort expenditure decision-making. (PsycINFO Database Record


Asunto(s)
Toma de Decisiones/fisiología , Giro del Cíngulo/fisiopatología , Imagen por Resonancia Magnética/métodos , Motivación/fisiología , Núcleo Accumbens/fisiopatología , Recompensa , Esquizofrenia/fisiopatología , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad
5.
Artículo en Inglés | MEDLINE | ID: mdl-26192817

RESUMEN

BACKGROUND: Anhedonia, the loss of interest or pleasure in reward processing, is a hallmark feature of major depressive disorder (MDD), but its underlying neurobiological mechanism is largely unknown. The present study aimed to examine the underlying neural mechanism of reward-related decision-making in patients with MDD. METHOD: We examined behavioral and neural responses to rewards in patients with first-episode MDD (N=25) and healthy controls (N=25) using the Effort-Expenditure for Rewards Task (EEfRT). The task involved choices about possible rewards of varying magnitude and probability. We tested the hypothesis that individuals with MDD would exhibit a reduced neural response in reward-related brain structures involved in cost-benefit decision-making. RESULTS: Compared with healthy controls, patients with MDD showed significantly weaker responses in the left caudate nucleus when contrasting the 'high reward'-'low reward' condition, and blunted responses in the left superior temporal gyrus and the right caudate nucleus when contrasting high and low probabilities. In addition, hard tasks chosen during high probability trials were negatively correlated with superior temporal gyrus activity in MDD patients, while the same choices were negatively correlated with caudate nucleus activity in healthy controls. CONCLUSIONS: These results indicate that reduced caudate nucleus and superior temporal gyrus activation may underpin abnormal cost-benefit decision-making in MDD.


Asunto(s)
Núcleo Caudado/fisiopatología , Toma de Decisiones/fisiología , Trastorno Depresivo Mayor/fisiopatología , Motivación/fisiología , Recompensa , Lóbulo Temporal/fisiopatología , Adulto , Anhedonia/fisiología , Mapeo Encefálico , Trastorno Depresivo Mayor/psicología , Femenino , Lateralidad Funcional , Humanos , Imagen por Resonancia Magnética , Masculino , Pruebas Neuropsicológicas , Probabilidad , Escalas de Valoración Psiquiátrica , Procesamiento de Señales Asistido por Computador
6.
Psychiatry Res ; 234(1): 144-51, 2015 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-26382106

RESUMEN

Cerebral morphological abnormalities in major depressive disorder (MDD) may be modulated by antidepressant treatment and course of illness in chronic medicated patients. The present study examined cortical thickness in patients with untreated first-episode MDD to elucidate the early pathophysiology of this illness. Here, we examined cortical thickness in patients with first-episode MDD (N=27) and healthy controls (N=27) using an automated surface-based method (in FreeSurfer). By assessing the correlation between caudate volume and cortical thickness at each vertex on the cortical surface, a caudate-cortical network was obtained for each group. Subsequent analysis was performed to assess the effect of anhedonia by the Temporal Experience of Pleasure Scale. We observed increased cortical thickness at the right orbital frontal cortex and the left inferior parietal gyrus in MDD patients compared with healthy controls. Furthermore, morphometric correlational analysis using cortical thickness measurement revealed increased caudate-cortical connectivity in the bilateral superior parietal gyrus in MDD patients. All changes were not related to anhedonia. These preliminary findings may reflect disorder manifestation close to illness onset and may provide insight into the early neurobiology of MDD.


Asunto(s)
Anhedonia/fisiología , Corteza Cerebral/patología , Trastorno Depresivo Mayor/patología , Lóbulo Frontal/patología , Lóbulo Parietal/patología , Adulto , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Tamaño de los Órganos , Adulto Joven
7.
Psychiatry Res ; 220(3): 874-82, 2014 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-25262638

RESUMEN

Anhedonia is a hallmark symptom of major depressive disorder (MDD). Preliminary findings suggest that anhedonia is characterized by reduced reward anticipation and motivation of obtaining reward. However, relatively little is known about reward-based decision-making in depression. We tested the hypothesis that anhedonia in MDD may reflect specific impairments in motivation on reward-based decision-making and the deficits might be associated with depressive symptoms severity. In study 1, individuals with and without depressive symptoms performed the modified version of the Effort Expenditure for Rewards Task (EEfRT), a behavioral measure of cost/benefit decision-making. In study 2, MDD patients, remitted MDD patients and healthy controls were recruited for the same procedures. We found evidence for decreased willingness to make effort for rewards among individuals with subsyndromal depression; the effect was amplified in MDD patients, but dissipated in patients with remitted depression. We also found that reduced anticipatory and consummatory pleasure predicted decreased willingness to expend efforts to obtain rewards in MDD patients. For individuals with subsyndromal depression, the impairments were correlated with anticipatory anhedonia but not consummatory anhedonia. These data offer novel evidence that motivational deficits in MDD are correlated with depression severity and predicted by self-reported anhedonia.


Asunto(s)
Toma de Decisiones , Trastorno Depresivo Mayor/diagnóstico , Trastorno Depresivo Mayor/psicología , Trastorno Depresivo/diagnóstico , Trastorno Depresivo/psicología , Motivación , Adolescente , Adulto , Anhedonia , Anticipación Psicológica , Femenino , Humanos , Masculino , Persona de Mediana Edad , Recompensa , Adulto Joven
8.
Ying Yong Sheng Tai Xue Bao ; 21(3): 675-82, 2010 Mar.
Artículo en Chino | MEDLINE | ID: mdl-20560324

RESUMEN

This paper studied the effects of Ca(2+) -carrier A23187 and Ca(2+) -chelator EGTA on the bud differentiation of cut flower chrysanthemum (Dendranthema grandiflorium 'Shenma') under photoperiodic induction, as well as the Ca2+ distribution and the sucrose, soluble sugar, and starch contents in 'Shenma' leaves during the differentiation. In the control, the leaf Ca2+ content was lower at the vegetative stage of apical bud (I), increased rapidly and reached a peak at the stage of initial differentiation (II), and decreased then. At stage I, the Ca2+ was mainly allocated in vacuole, cell wall, and cell lacuna; while at stage II, it was more in cytoplasm. Compared with the control, the leaf Ca2+ content of A23187-treated plants increased significantly, and the days of initiation and ending of bud differentiation were advanced by 2 days and 3 days, respectively. On the other hand, the leaf Ca2+ content of EGTA-treated plants decreased significantly, and the days of initiation and ending of bud differentiation were postponed by 4 days and 8 days, respectively. For both A23187- and EGTA-treated plants, their leaf Ca2+ at stage II was more allocated in cytoplasm. The leaf sucrose and soluble sugar contents of A23187-treated plants reached a peak on the 2nd day after treatment, and the time to reach the peak was shortened by 2 days, compared with the control, which was consistent with the peak time of Ca2+. The leaf sucrose and soluble sugar contents of EGTA-treated plants had no significant changes on the 2nd day of treatment, but increased rapidly and reached the peak on the 8th day of treatment (stage II), and then decreased. However, the leaf sucrose and soluble sugar contents during the whole period of bud differentiation were higher than those before photoperiodic induction. The leaf starch content of A23187-treated plants and the control decreased 2 days after treatment, while that of EGTA-treated plants began to decrease 8 days after treatment, and maintained at a lower level by the end of bud differentiation. The results indicated that Ca2+ and carbohydrates participated in the flower formation of chrysanthemum under photoperiodic induction.


Asunto(s)
Calcimicina/farmacología , Calcio/metabolismo , Carbohidratos/biosíntesis , Chrysanthemum/metabolismo , Ácido Egtácico/farmacología , Quelantes/farmacología , Chrysanthemum/efectos de los fármacos , Chrysanthemum/fisiología , Flores/efectos de los fármacos , Flores/fisiología , Fotoperiodo
9.
World J Gastroenterol ; 16(7): 886-96, 2010 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-20143469

RESUMEN

AIM: To perform a meta-analysis of observational studies and randomized controlled trials (RCTs) on the association between Helicobacter pylori (H. pylori) and iron deficiency anemia (IDA). METHODS: A defined search strategy was used to search Medline, Embase, the Cochrane Library, Clinical Trials, Cochrane Central Register of Controlled Trials, Premedline and Healthstar. Odds ratio (OR) was used to evaluate observational epidemiology studies, and weighted mean difference (WMD) was used to demonstrate the difference between control and intervention groups. RESULTS: Fifteen observational studies and 5 RCTs were identified and used for calculation. The pooled OR for observational studies was 2.22 (95% CI: 1.52-3.24, P < 0.0001). The WMD for hemoglobin (HB) was 4.06 g/L (95% CI: -2.57-10.69, P = 0.01), and the WMD for serum ferritin (SF) was 9.47 mug/L (95% CI: -0.50-19.43, P < 0.0001). Results were heterogeneous for all comparisons. CONCLUSION: This meta-analysis on observational studies suggests an association between H. pylori and IDA. In RCTs, eradication of H. pylori can improve HB and SF levels but not significantly.


Asunto(s)
Anemia Ferropénica/microbiología , Infecciones por Helicobacter/microbiología , Helicobacter pylori/patogenicidad , Adolescente , Adulto , Anciano , Anemia Ferropénica/sangre , Anemia Ferropénica/tratamiento farmacológico , Antibacterianos/uso terapéutico , Biomarcadores/sangre , Distribución de Chi-Cuadrado , Niño , Preescolar , Medicina Basada en la Evidencia , Femenino , Ferritinas/sangre , Infecciones por Helicobacter/sangre , Infecciones por Helicobacter/complicaciones , Infecciones por Helicobacter/tratamiento farmacológico , Hemoglobinas/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Ensayos Clínicos Controlados Aleatorios como Asunto , Medición de Riesgo , Factores de Riesgo , Resultado del Tratamiento , Adulto Joven
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