Efficient Colorimetric Fluoride Anion Chemosensors With Varied Colors Based on Simple Aminobenzodifuranone Organic Π-Conjugated Dyes.

High selectivity and sensitivity detection of fluoride anions (F-) in an organic solution by the naked eye has always been a challenge. In this investigation, a simple compound based on aminobenzodifuranone (ABDF) was designed and synthesized. Deprotonation of the amino moiety caused by F- is responsible for a color change from dark blue to various colors (colorless, yellow, orange, and red) in different common organic solvents due to a blue shift over 200 nm in the UV/Vis spectrum. The color change is quite visible to the naked eye under ambient light. The detection limit for F- can reach a concentration of as low as 5.0 × 10-7 M with high selectivity, even in a solution containing multiple anions.

[Effects of exogenous spermidine on mitochondrial function of tomato seedling roots under salinity-alkalinity stress].

Two cultivars of tomato (Solanum lycopersicum, cvs. 'Jinpengchaoguan' and 'Zhongza No. 9', with the former being more tolerant to saline-alkaline stress) seedlings grown hydroponically were subjected to salinity-alkalinity stress condition (NaCl: Na2SO4:NaHCO3:Na2CO3 = 1:9:9:1) without or with foliar application of 0.25 mmol . L-1 spermidine (Spd), and the root morphology and physiological characteristics of mitochondrial membrane were analyzed 8 days after treatment, to explore the protective effects of exogenous Spd on mitochondrial function in tomato roots under salinity-alkalinity stress. The results showed that the salinity-alkalinity stress increased the concentrations of both mitochondrial H2O2 and MDA as well as the mitochondrial membrane permeability in the roots of the two cultivars, while it decreased the mitochondrial membrane fluidity, membrane potential, Cyt c/a and H+-ATPase activity, which impaired the mitochondria and therefore inhibited the root growth; and these effects were more obvious in 'Zhongza No. 9' than in 'Jinpengechaoguan'. Under the salinity-alkalinity stress, foliar application Spd could effectively decrease the concentrations of mitochondrial H2O2 and MDA and mitochondrial membrane permeability, while increased the mitochondrial membrane fluidity, membrane potential, Cyt c/a and H+-ATPase activity. These results suggested that exogenous Spd could effectively mitigate the damage on mitochondria induced by salinity-alkalinity stress, and the alleviation effect was more obvious in 'Zhongza No. 9' than in 'Jinpengchaoguan'.

[Effect of exogenous γ-aminobutyric acid on NO3--N assimilation in muskmelon under Ca(NO3)2 stress]. / 外源γ-æ°¨åŸºä¸é ¸å¯¹Ca(NO3)2胁迫下甜瓜幼苗NO3--N同化的影响.

The effect of exogenous γ-aminobutyric acid (GABA) on NO3--N assimilation in muskmelon under Ca(NO3)2 stress was investigated in ' Yipintianxia 208', a salt-sensitive melon variety cultured under deep flow hydroponics which simulated soil salinization. The results showed that under Ca(NO3)2 stress, the activities of nitrate reductase (NR), glutamate synthetase (GS) and glutamate amino transferase (GOGAT) in muskmelon seedlings were significantly reduced, while the activities of glutamate dehydrogenase (GDH), glutamate oxaloacetate transaminase (GOT) and glutamate pyruvate aminotransferase (GPT) were enhanced, leading to increased contents of NH4+-N and total amino acids, and decreased contents NO3--N and soluble protein in muskmelon, which further severely inhibited plant growth and photosynthesis of muskmelon seedlings. Exogenous GABA effectively improved the absorption of NO3--N in muskmelon roots and its transportation from root to shoot under Ca(NO3)2 stress, and improved NH4+-N assimilation by enhancing NR, GS and GOGAT activities in muskmelon seedlings. Exogenous GABA also reduced NH4+ release by limiting GDH deamination, thus further alleviated the toxication of NH4+-N induced by Ca(NO3)2 stress. In addition, foliage spraying of GABA could regulate amino acids metabolic pathways and promote protein synthesis. The results suggested that exogenous GABA could improve NO3--N assimilation and regulate amino acids metabolism to alleviate Ca(NO3)2 stress damage in muskmelon seedlings.

[Response of reactive oxygen metabolism in melon chloroplasts to short-term salinity-alkalinity stress regulated by exogenous γ-aminobutyric acid].

The regulatory effect of exogenous γ-aminobutyric acid (GABA) on metabolism of reactive oxygen species (ROS) in melon chloroplasts under short-term salinity-alkalinity stress were investigated in melon variety 'Jinhui No. 1', which was cultured with deep flow hydroponics. The result showed that under salinity-alkalinity stress, the photosynthetic pigment content, MDA content, superoxide anion (O2·) production rate and hydrogen peroxide (H2O2) content in chloroplast increased significantly, the contents of antioxidants ascorbic acid (AsA) and glutathione (GSH) increased, and the activities of H⁺-ATPase and H⁺-PPiase were inhibited obviously. With exogenous GABA application, the accumulations of O2·, MDA and H2O2 induced by salinity-alkalinity stress were inhibited. Exogenous GABA alleviated the increase of photosynthetic pigment content, improved the activity of SOD, enzymes of AsA-GSH cycle, total AsA and total GSH while decreased the AsA/DHA ratio and GSH/GSSH ratio. Foliar GABA could enhance the H⁺-ATPase and H⁺-PPiase activities. Our results suggested that the exogenous GABA could accelerate the ROS metabolism in chloroplast, promote the recycle of AsA-GSH, and maintain the permeability of cell membrane to improve the ability of melon chloroplast against salinity-alkalinity stress.

Blood rheological properties are strongly related to the metabolic syndrome in middle-aged Chinese.

The current investigation sought to evaluate the relation between hemorheological properties and the metabolic syndrome. 1400 office workers aged 35 to 59 years were enrolled in this study. Waist circumference and blood pressure were determined. Plasma high-density lipoprotein (HDL cholesterol), triglyceride, fasting blood glucose, plasma insulin and whole blood viscosity (WBV) at a high-shear rate of 200 s(-1) were measured at the attendance. Metabolic syndrome was defined according to National Cholesterol Education Program (NCEP)/ATP III guidelines. The metabolic syndrome was identified in 18% of this sedentary population. Mean WBV was 4.71+/-0.56 mPa s. One-way ANOVA indicated WBV increased across subjects with 0-4 metabolic syndrome components (F=3.86, p<0.01). The highest vs. lowest quartiles of WBV occurred significantly more often among subjects as the number of metabolic syndrome components increased. Across five categories of the metabolic syndrome, the frequencies of the occurrence of the highest vs. lowest quartiles were: 0.40, 0.87, 1.31, 1.92, and 4.80, respectively, showing a significant correlation (R=0.817, p<0.05). Univariate logistic regression analysis showed that the prevalence of hyperviscosity was predicted positively by waist circumference (OR=1.018, 95% CI: 1.002-1.035, p<0.05) and negatively by HDL cholesterol (OR=0.295, 95% CI: 0.133-0.680, p<0.01), independently of age, sex, and smoking status. In summary, this study has shown that WBV is strongly related to the severity of the metabolic syndrome. We suggest that the hemorheological parameters could potentially be used as an additional indicator of the metabolic syndrome.