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  • Author or Editor: Q. Zhang x
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Abstract  

Two sufficient conditions for a finite group G to be p-supersolvable have been obtained. For example (Theorem 1.1), let N be a normal subgroup of G such that G/N is p-supersolvable for a fixed odd prime p and let N p be a Sylow p-subgroup of N. Suppose that N is p-solvable and Ω1(N p) is generated by the subgroups of order p of N p which are normal in N G(N p). Then G is p-supersolvable.

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Abstract  

Fingernails of pathologically diagnosed normal people, light esophageal epitheliosis patients, severe esophageal epitheliosis patients and esophageal cancer patients were irradiated and their elemental contents were determined by INAA. Multivariate statistical treatment of Ca, Cl, K. Mg, Se and Zn data shows that esophageal cancer patients are distinguishable from non-cancer patients. The accuracy computed by neural networks is greater than 80%.

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Abstract  

By using 188Re as a radiotracer, the extraction behavior of Re(VII) by a tertiary amine extractant N-235 from HCl and the back-extraction behavior of Re(VII) by HNO3 and ammonia were studied. A chemical separation procedure, which combined the acid alumina column and solvent extraction was established. The procedure was rapid and efficient for the separation of 186Re from 186W irradiated by 16 MeV deuterons. No-carrier-added 186ReO4 saline solution with high specific volume activity was obtained. The overall recovery yield of 186Re was about 85%.

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Summary

High-performance capillary electrophoresis with amperometric detection (CE-AD) has been used for analysis of eight bioactive components of the leaves, stems, and roots of Valeriana wallichii DC, after a relatively simple extraction procedure with ethanol. Under the optimum conditions, the eight components can be well separated or (apigenin and luteolin) separated nearly to baseline within 23 min by use of 50 mM borax (pH 9.2) as running buffer and a separation potential of 16 kV. Linearity was excellent over two orders of magnitude of concentration and detection limits (S/N = 3) ranged from 1.7 × 10−7 to 1.8 × 10−8 g mL−1. This method was used for comparison of the concentrations of the bioactive compounds in different parts of the plant on the basis of their electropherograms or ‘characteristic electrochemical profiles’. Assay results were satisfactory.

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Abstract

Th17 cells, a class of CD4+ T cells, have been identified as novel effector cells, which play a pivotal role in several inflammatory and autoimmune diseases. 1,25-Dihydroxyvitamin D3 (1,25(OH)2D3), the active form of vitamin D, has emerged as a direct regulator of immune system function in humans. Accumulating reports demonstrated that 1,25(OH)2D3 possessed anti-inflammatory activity on Th17 cells to maintain immunologic homeostasis. This report will review the novel immune regulatory role of 1,25(OH)2D3 in its potential use for Th17 cell-related inflammatory and autoimmune conditions.

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Salt stress is one of the major abiotic stress which severely limits plant growth and reduces crop productivity across the world. In the present study, the effects of exogenous pyridoxal-5-phosphate (vitamin B6, VB6) on seedling growth and development of wheat under salt stress were investigated. The results showed that exogenous application of pyridoxal-5-phosphate (VB6) significantly increased the RWC, biomass, the concentration of photosynthetic pigments, proline, the activities of superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), together with decreasing the content of Malondiadehyde (MDA) and hydrogen peroxide (H2O2) in wheat leaves under salt stress. Meanwhile, the transcript level of P5CR, P5CS, SOD, TaSOS1 and TaSOS4 were also up-regulated after treatment with pyridoxal-5-phosphate. VB6 acts as a signal in regulating the activities of plant antioxidant enzymes and SOS pathway to improve resistance to salt stress. The current study results may give an insight into the regulatory roles of VB6 in improving salt stress and VB6 could be an easily and effective method to improve salt-stress tolerance to wheat in the field condition. It is urgency to understand the molecular mechanism of VB6 to enhance the salt tolerance of wheat in the next work.

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Berberine, a primary pharmacological active constitute of Coptidis Rhizoma, could inhibit neuronal apoptosis in cerebral ischemia. Here, we aimed to investigate whether and how HIF-1 is implicated in the anti-apoptosis effect of berberine on neurons under hypoxia/ischemia. Viability of PC12 cells treated with berberine prior to or following CoCl2-induced hypoxia was evaluated. Annexin V-PI staining was employed to analyse cell apoptosis ratio. HIF-1α and apoptosis-associated molecules were detected via Western blotting. TUNEL and immunohistochemistry were used to demonstrate apoptosis, HIF-1α and p53 levels in cerebral tissue of middle cerebral artery occlusion (MCAO) rats. Berberine pretreatment promoted PC12 cells survival and inhibited apoptosis under hypoxia condition. At the same time, it decreased cell viability and enhancement of apoptosis were observed with berberine treatment under hypoxia. Decreased HIF-1α, caspase 9, caspase 3 and increased Bcl-2/Bax ratio were responsible for the anti-apoptosis of berberine pretreatment. However, pro-apoptosis by berberine under hypoxia was indicated with opposing regulation of those molecules. Significant reduction of apoptosis, HIF-1α and p53 were found in cerebral tissue of MCAO rats treated with berberine. The present study suggests that berberine regulates neuronal apoptosis in cerebral ischemia, which might be dependent on the degree of cell injury. HIF-1 and the followed apoptotic pathway are involved in those effects of berberine.

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Authors: B. Lin, L. Yang, H. Dai, Q. Hou and L. Zhang

Abstract  

Soybean oil based polyols (5-OH polyol, 10-OH polyol and 15-OH polyol) were synthetised from epoxidized soybean oil. The melting peak of polyols and the relationship between melting peak and the number-average functionality of hydroxyl in polyols were investigated by differential scanning calorimetry (DSC). The thermal decomposition of polyols and some of their thermal properties by thermogravimetry (TG) and derivative thermogravimetry (DTG) were also studied. The thermal stability of polyols in a nitrogen atmosphere was very close hence they had a same baseplate of triglyceride for polyols. The extrapolated onset temperature of polyols in their thermal mass loss, first step had a decreasing order: 5-OH polyol>10-OH polyol>15-OH polyol due to the difficulty in forming multiple elements ring of them had the same order. The thermal behavior of polyols under non-isothermal conditions using Friedman’s differential isoconversional method with different heating rates indicated that the 5-OH polyol had the lowest activation energy in thermal decomposition amongst these polyols according to the same fractional mass loss because of the weakest intramolecular oligomerization. The 15-OH polyol was prior to reach the mass loss region because the six-member ring is more stable than the three-member ring from 10-OH polyol and more easily formed.

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Abstract  

A fully automated adiabatic calorimeter controlled on line by a computer used for heat capacity measurements in the temperature range from 80 to 400 K was constructed. The hardware of the calorimetric system consisted of a Data Acquisition/Switch Unit, 34970A Agilent, a 7 1/2 Digit Nano Volt /Micro Ohm Meter, 34420A Agilent, and a P4 computer. The software was developed according to modern controlling theory. The adiabatic calorimeter consisted mainly of a sample cell equipped with a miniature platinum resistance thermometer and an electric heater, two (inner and outer) adiabatic shields, two sets of six junction differential thermocouple piles and a high vacuum can. A Lake Shore 340 Temperature Controller and the two sets of differential thermocouples were used to control the adiabatic conditions between the cell and its surroundings. The reliability of the calorimeter was verified by measuring the heat capacities of synthetic sapphire (α-Al2O3), Standard Reference Material 720. The deviation of the data obtained by this calorimeter from those published by NIST was within ±0.1% in the temperature range from 80 to 400 K.

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Summary

A reversed-phase high-performance liquid chromatographic method was developed for the first time to simultaneously determine salicin and eight flavonoids in leaves of Salix matsudana, that is salicin, luteolin-7-O-glucoside, myricetin, apigenin-3′-oxyethyl-7-O-glucoside, rutin, quercetin, luteolin, kaempferol and apigenin. The separation of these compounds was achieved on a reversed phase C18 column (250 × 4.6 mm, 5 μm), with linear gradient of methanol in 0.2% phosphoric acid solution with a flow rate of 1.0 mL/min with UV detection at 246 nm. The calibration curves for the determination of all analytes showed good linearity over the investigated ranges (r > 0.999). The % relative standard deviation (% RSD) values were less than 0.34%, and the recoveries were between 95.79% and 99.94%. The values of luteolin-7-O-glucoside, salicin, myricetin, apigenin-3′-oxyethyl-7-O-glucoside, rutin, quercetin, luteolin, kaempferol, and apigenin were 1.0 μg g−1, 20.0 μg g−1, 32.9 μg g−1, 2.0 μg g−1, 29.5 μg g−1, 6.0 μg g−1, 1.0 μg g−1, 3.5 μg g−1, and apigenin was not found in the sample. This developed method can be used for evaluating the quality of different plant materials.

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