渗透胁迫对小麦胚芽鞘内多胺的种类、形态和含量的影响

用高压液相色谱法研究了豫麦18（抗旱性较强）和扬麦9号（抗旱性较弱）小麦胚芽鞘中三种不同形态的多胺（polyamine,PA）：游离态多胺（PA）、高氯酸可溶性结合态多胺（ps结合态PA）和高氯酸不溶性结合态多胺（PIS结合态PA）与渗透胁迫的关系。结果发现：渗透胁迫2d,豫麦18胚芽鞘中的游离态Spd和游离态Spm的含量明显上升,而扬麦9号的游离态Put的上升明显。S-腺苷蛋氨酸脱羧酶（S—AMDC）的抑制剂——甲基乙二醛-双（鸟嘌呤腙）（MGBG）处理豫麦18,明显抑制了渗透胁迫诱导的游离态Spd和游离态Spm的增加,并且加重了渗透胁迫伤害,外源Spd处理扬麦9号明显促进了渗透胁迫诱导的游离态Spd和游离态Spm的增加,并且减缓了渗透胁迫的伤害。渗透胁迫下,豫麦18胚芽鞘中的PS结合态PA和PIS结合态PA的上升幅度都明显大于扬麦9号。菲咯啉（o—Phen）抑制渗透胁迫下PIS结合态PA的合成并加重了渗透胁迫对胚芽鞘的伤害。这些结果表明：小麦胚芽鞘中的游离态Spd、游离态Spm、PS结合态PA和PIS结合态PA的升高有利于增强渗透胁迫抗性。     

水分胁迫下丛枝菌根真菌对枳实生苗生长和渗透调节物质含量的影响

采用盆栽试验研究了水分胁迫下接种丛枝菌根真菌摩西球囊霉(Glomaus mosseae)对枳[Poncirustrifoliat(L.)Raf.]实生苗的生长和渗透调节物质含量的影响.结果表明,在土壤含水量为20%、16%和12%条件下,接种G.mosseae能够增加植株的生长(株高、茎粗、叶面积、地上部干重、地下部干重和植株干重),促进植株根系活跃吸收面积和根际土壤有效磷的吸收,提高叶片和根系可溶性糖含量的积累,降低叶片脯氨酸含量,增强植株的水分利用效率(达20%～40%),使枳实生苗的抗旱能力得到增强.土壤含水量为20%和16%条件下接种G.mosseae对植株的效果较土壤含水量为12%条件下更显著.12%的土壤含水量严重抑制Gmosseae的侵染,说明丛枝菌根侵染程度轻,其对植物的效果也差.     

Effects of indole‐3‐butyric acid on growth,pigments and UV‐screening compounds in Nostoc linckia

In the present research, the effect of indole‐3‐butyric acid (IBA) on the growth, and the production of some primary and secondary metabolites was studied in Nostoc linckia. In this respect, algae cultures were supplied with 0, 0.01, 0.1, 1, 10, and 100 μM IBA for 14 days. IBA at concentrations of 10 and 100 μM induced algal growth expressed as fresh weight in N. linckia. Treatment with IBA at all concentrations stimulated heterocyst formation. In addition, low concentrations of IBA (0.01, 0.1, and 1 μM) had a stimulatory effect on chlorophyll a and carotenoids accumulation. In contrast, higher concentrations of IBA induced the accumulation of phycocyanin, allophycocyanin, and phycoerythrin in the treated algae. In this case, IBA at the concentration of 10 μM was more effective. A significant decrease in protein content was observed in the algae treated by 0.01 μM IBA. All concentrations of IBA caused a decrease in sugar content, but lower concentrations were more effective. IBA application in all of the concentrations except 100 μM increased oligosaccharide‐linked mycosporine‐like amino acids (OS‐MAAs) content. Lower concentrations had a more significant effect on increasing OS‐MAAs content. However the concentrations of 10 and 100 μM IBA decreased scytonemin content. These results indicated the stimulatory impact of IBA on weight, heterocyst formation, and photosynthetic pigments in N. linckia.     

Enantiomers of fuscumol acetate comprise the aggregation‐sex pheromone of the South American cerambycid beetle Psapharochrus maculatissimus,and likely pheromones of the cerambycids Eupromerella plaumanni and Hylettus seniculus

There is increasing evidence that pheromone chemistry within the large coleopteran family Cerambycidae is often highly conserved, with numerous related species sharing the same pheromone components. As a result, traps containing these components can attract multiple cerambycid species simultaneously. In the present study, we exploited this concept in the identification of the male‐produced aggregation‐sex pheromone of the South American species Psapharochrus maculatissimus (Bates) (Coleoptera: Cerambycidae, subfamily Lamiinae, tribe Acanthoderini). Initially, live adults of both sexes were caught using a trap baited with a lure containing a blend of known cerambycid pheromone components. Headspace volatiles were collected from live beetles and analyzed by coupled gas chromatography‐mass spectrometry. Males of P. maculatissimus sex‐specifically produced a 1:38 blend of (R)‐fuscumol acetate ([2R,5E]‐6,10‐dimethylundeca‐5,9‐dien‐2‐yl acetate) and (S)‐fuscumol acetate, which were both components of the pheromone lures to which they had been attracted. In more focused field trials, traps baited with the (S)‐enantiomer, or a blend approximating the natural 1:38 ratio of (R)‐ to (S)‐enantiomers, attracted adults of both sexes in approximately equal numbers. During bioassays, adults of the lamiine species Eupromerella plaumanni (Fuchs) (tribe Acanthoderini) and Hylettus seniculus (Germar) (Acanthocinini) also were attracted, but to different lures, with E. plaumanni being attracted to the racemic mixture of the two enantiomers of fuscumol acetate, whereas H. seniculus was attracted specifically to (R)‐fuscumol acetate. Our results suggest that differences between these sympatric species in the stereochemistry of fuscumol acetate impart species‐specificity to pheromone communication channels, similar to what has been found recently with lamiine species from other continents.     

等渗Ca(NO3)2和NaCl胁迫对黄瓜幼苗生长及渗透调节物质含量的影响

采用营养液培养方法,以耐盐性较弱的‘津春2号’黄瓜品种为试材,研究了等渗Ca(NO3)2和NaCl胁迫对黄瓜幼苗生长、根系电解质渗透率、根系活力、Na+和K+含量及渗透调节物质含量的影响。结果显示:(1)在84mmol.L-1 NaCl和56mmol.L-1 Ca(NO3)2等渗胁迫下,黄瓜幼苗鲜重和干重均显著下降,且NaCl处理下降的幅度大于等渗Ca(NO3)2处理。(2)NaCl主要通过对黄瓜根系的伤害来抑制植株生长,表现为根系活力下降、根系质膜透性增大、Na+大量积累、K+含量显著下降、Na+/K+明显上升,最终导致根冠比下降;而Ca(NO3)2处理对根系质膜透性、K+含量、Na+/K+的影响均小于NaCl胁迫,且根系活力和根冠比上升,但Ca(NO3)2胁迫后叶片含水量和渗透调节能力均小于NaCl胁迫。(3)NaCl胁迫条件下,黄瓜幼苗内渗透调节物质以可溶性糖为主,而Ca(NO3)2胁迫以可溶性蛋白为主。研究表明,NaCl胁迫对黄瓜幼苗的伤害大于等渗Ca(NO3)2,NaCl主要通过破坏根系质膜结构影响植株生长,而Ca(NO3)2主要通过引起地上部生理干旱来影响植株生长。     

A Comparative Study on Hulled Adlay and Unhulled Adlay through Evaluation of Their LPS‐Induced Anti‐Inflammatory Effects,and Isolation of Pure Compounds

Coicis semen (=the hulled seed of Coix lacryma‐jobi L. var. ma‐yuen (Rom.Caill. ) Stapf ; Gramineae), commonly known as adlay and Job's tears, is widely used in traditional medicine and as a nutritious food. Bioassay‐guided fractionation of the AcOEt fraction of unhulled adlays, using measurement of nitric oxide (NO) production on lipopolysaccharide (LPS)‐stimulated RAW 264.7 macrophage cells, led to the isolation and identification of two new stereoisomers, (+)‐(7′S,8′R,7″S,8″R)‐guaiacylglycerol β‐O‐4′‐dihydrodisinapyl ether ( 1 ) and (+)‐(7′S,8′R,7″R,8″R)‐guaiacylglycerol β‐O‐4′‐dihydrodisinapyl ether ( 2 ), together with six known compounds, 3 – 8 . Compounds 3 and 4 exhibited inhibitory activities on LPS‐induced NO production with IC₅₀ values of 1.4 and 3.7 μM , respectively, and suppressed inducible nitric oxide synthase (iNOS) and cyclooxygenase‐2 (COX‐2) protein expressions in RAW 264.7 macrophage cells. Simple high‐performance liquid chromatography with ultraviolet detection (HPLC/UV) was used to compare the AcOEt fraction of unhulled adlays responsible for the anti‐inflammatory activity in RAW 264.7 cells and the inactive AcOEt fraction of hulled adlays.     

Effects of UV‐A exposures on longevity and reproduction in Helicoverpa armigera,and on the development of its F1 generation

Abstract Helicoverpa armigera adults display a conspicuous positive phototactic behavior to light stimuli, and are especially sensitive to ultraviolet (UV) light. The effects of UV‐A (longwave) exposures on adult longevity and reproduction in H. armigera were investigated, as well as the development of the F₁ generation. Paired adults were exposed to UV‐A for various time periods (0, 1, 5 and 9 h/day), until the end of adult life. The results showed that adult longevity decreased with increasing exposure time for both sexes, and a significant decrease was observed after exposure for 5 and 9 h/day. Fecundity increased when adults were exposed for 1 and 5 h/day, and a significant difference was observed in the 5 h/day group. Oviposition rates of females in all treatments were significantly higher than in the control. Exposure to UV‐A for longer periods (5 and 9 h/day) caused a decline in cumulative survival of F₁ immature stages, but no significant differences were found in egg hatch, pupation and eclosion. The developmental periods of F₁ larvae were significantly prolonged after exposure to UV‐A for 5 and 9 h/day. UV‐A radiation had no significant effects on F₁ pupal period.     

Effects of UV‐A Radiation on Desmodesmus armatus: Changes in Growth Rate,Pigment Content and Morphological Appearance

Laboratory cultures of Desmodesmus armatus (R. Chod. ) Hegew. were grown under different levels of photosynthetically active radiation (PAR) supplemented with 3.75 mW · cm^–2 UV‐A radiation. Growth rate was monitored daily, chlorophyl‐a concentration, total carotenoid content, cell number and the relative abundance of different coenobial forms was determined at the end of each experiment. Exposure to UV‐A radiation resulted in an increasing inhibition of growth towards higher PAR levels, reaching 100% at 400 µmol · m^–2 · s^–1. Cellular carotenoid content was higher in the presence of UV‐A radiation, on the other hand no differences were observed in cellular chlorophyll‐a concentration. UV‐A radiation also induced changes in coenobium formation with a decreasing proportion of 4‐celled coenobia and an increase in the abundance of 2‐celled and teratologic coenobia, suggesting that high intensity UV‐A radiation may influence cell cycle events or morphology development. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Protective Antioxidant Effects of Amentoflavone and Total Flavonoids from Hedyotis diffusa on H2O2‐Induced HL‐O2 Cells through ASK1/p38 MAPK Pathway

In this study, total flavonoids and total triterpenoid acid were extracted with ethyl acetate from Hedyotis diffusa Willd, and hepatoprotective activities of them and five compounds from total flavonoids against H₂O₂ induced hepatocyte damage on HL‐02 cells were determined. In particular, amentoflavone and total flavonoids had influence on the leakage of ALT, AST, LDH, the activities of SOD and the content of MDA. They effectively reduced the loss of MMP, the release of Cyt C, and then inhibited activation of caspase‐3/caspase‐9 cascade in hepatotoxic cells. The contents of ROS were significantly reduced to inhibit p38 in amentoflavone and flavonoids groups which decreased ASK1 and p‐p38 levels through increasing thioredoxin Trx1 and reductase TrxR1. These results suggesting that the antioxidant protection of amentoflavone and flavonoids might be reducing ROS to inhibit the H₂O₂‐induced upstream of pathway via increasing levels of Trx1 and TrxR1, which were pivotal in blocking the down streaming effectors of ASK1/p38 MAPK pathway and alleviating hepatotoxicity.     

部分根系供磷对黄瓜根系和幼苗生长及根系酸性磷酸酶活性影响

通过分根处理研究了部分根系供磷对黄瓜幼苗生长、植株体内的含磷量及根系酸性磷酸酶活性的影响。结果表明 ,2 0 %根系缺磷 (1条根缺磷 ,4条根供磷 )可以促进根系及植株地上部的生长 ,其根系及地上部的生物量分别是正常生长植株的 1.39倍和 1.2 1倍。2 0 %根系缺磷 ,还可以促进其它供磷根系对磷的吸收。分根处理后 ,2 0 %根系缺磷不影响植物对磷营养的需要 ,但却表现出了R/S比增大的典型缺磷反应 ,说明植物感应缺磷根系起着比地上部更为重要的作用。分根处理后不供磷根系的酸性磷酸酶活性显著高于供磷根系的酸性磷酸酶活性 ,并且根系的酸性磷酸酶活性只与根系的含磷量显著相关 ,与地上部的磷营养状况关系不明显。这说明 ,缺磷条件下 ,黄瓜植株根系分泌酸性磷酸酶活性的增高 ,是黄瓜根系对低磷胁迫的适应性机理 ,而不是地上部改善体内磷营养的调控机理。     

Differential responses to oxidative stress and calcium influx on expression of the transforming growth factor‐β family in myoblasts and myotubes

Changes in gene expression of TGF‐β family members and their receptors in response to treatment with H₂O₂ and a calcium ionophore, A23187, were examined in C2C12 myoblasts and myotubes. The expression of Myf5, an initial regulator of myogenesis, was increased by A23187, and H₂O₂ inhibited the up‐regulation of Myf5. Treatment with H₂O₂ decreased the expression of MHC IIb, a protein component of the myofibrils, irrespective of the presence of A23187, suggesting an inhibitory role of oxidative stress for myogenesis. Expression of ligands and receptors for the TGF‐β family was modulated in response to H₂O₂ and A23187. Treatment with H₂O₂ decreased expression of TGF‐β3, BMP‐4, ALK4, ALK5, and ActRIIB, and increased expression of inhibin α and inhibin βA in either the myoblast stage or the myotube stage, or both. A23187 potentiated down‐regulation of BMP‐4 and ALK4 expression, and up‐regulation of TGF‐β1, TGF‐β2, inhibin α, inhibin βA, ALK2, and ALK3 expression. These results indicate that oxidative stress and Ca²⁺ influx affect expression of the TGF‐β family in C2C12 myoblasts and myotubes. Copyright © 2009 John Wiley & Sons, Ltd.     

Differential Effect of DDT,DDE, and DDD on COX‐2 Expression in the Human Trophoblast Derived HTR‐8/SVneo Cells

The purpose of this study was to investigate the effect of 1,1,1‐trichloro‐2,2‐bis‐(chlorophenyl)ethane (DDT), 1,1‐bis‐(chlorophenyl)‐2,2‐dichloroethene (DDE), and 1,1‐dichloro‐2,2‐bis(chlorophenyl)ethane (DDD) isomers on COX‐2 expression in a human trophoblast‐derived cell line. Cultured HTR‐8/SVneo trophoblast cells were exposed to DDT isomers and its metabolites for 24 h, and COX‐2 mRNA and protein expression were assessed by RT‐PCR, Western blotting, and ELISA. Prostaglandin E₂ production was also measured by ELISA. Both COX‐2 mRNA and protein were detected under control (unexposed) conditions in the HTR‐8/SVneo cell line. COX‐2 protein expression and prostaglandin E₂ production but not COX‐2 mRNA levels increased only after DDE and DDD isomers exposure. It is concluded that DDE and DDD exposure induce the expression of COX‐2 protein, leading to increased prostaglandin E2 production. Interestingly, the regulation of COX‐2 by these organochlorines pesticides appears to be at the translational level. © 2012 Wiley Periodicals, Inc. J Biochem Mol Toxicol 26:454‐460, 2012; View this article online at wileyonlinelibrary.com . DOI 10:1002/jbt.21444     

First Syntheses of Melophlins P,Q, and R,and Effects of Melophlins on the Growth of Microorganisms and Tumor Cells

The marine tetramic acid (=1,5‐dihydro‐4‐hydroxy‐2H‐pyrrol‐2‐ones) derivatives melophlin P, Q, and R ( 1p – 1r , resp.) were synthesized for the first time in only four steps. Together with the congenerous melophlins A–C and G, they were also tested for antimicrobial and cytotoxic effects. Melophlins B, C, P, Q, and R, which share a 5‐Me residue, showed some antibacterial activity, mainly in Gram‐positive bacteria. Melophlins B, C, and R, which have Me‐branched 3‐acyl side chains in common, inhibited the growth of cells of human KB‐3‐1 cervix carcinoma, A‐498 kidney carcinoma, and U‐937 leukemia with IC₅₀ values <10 μM . They were similar in activity to cisplatin. Melophlin Q, also Me‐branched, was astoundingly specific in inhibiting A‐498 kidney cancer cells, while melophlin P inhibited U‐937 leukemia cells particularly well. The position of the Me branch is decisive for the magnitude of the antiproliferative effect of the melophlin couples B/C and R/Q.     

UV‐radiation effects on photosynthesis and photoprotection in gametophytic and sporophytic stages of the freshwater red alga Kumanoa ambigua (Rhodophyta,Batrachospermales)

The aim of this study was to analyze the photosynthetic performance of gametophytic and sporophytic (‘Chantransia’) stages of Kumanoa ambigua in culture under UV radiation. We hypothesized that both life history stages of K. ambigua would exhibit different photosynthetic responses to UVR exposure. Experiments were performed under three conditions: (i) photosynthetically active radiation (PAR) only (400–700 nm), P control; (ii) PAR + UVA (320–700 nm), PA treatment; and (iii) PAR + UVA + UVB (280–700 nm), PAB treatment. The photosynthetic parameters were measured as in vivo chlorophyll a fluorescence. Differences were found between life stages, observing higher values of NPQ and effective quantum yields (ΔF/F_m′) under UVA and PAR in gametophytes compared to sporophytes. One type of mycosporine‐like amino acid (MAA) was detected in the gametophyte in all treatments, but not in the ‘Chantransia’ stage. The increased photosynthetic performance for some parameters and the presence of MAA in gametophyte suggest that it is less sensitive to UV radiation, particularly UVA, in comparison to sporophyte under culture conditions. This approach is relevant for a better understanding of the adaptation and physiological acclimation of freshwater Rhodophyta to varying light climates in terms of global changes.     

The effects of the DNA methyltranfserases inhibitor 5‐Azacitidine on ageing,oxidative stress and DNA methylation of adipose derived stem cells

Human adipose tissue is a great source of adult mesenchymal stem cells (MSCs) which are recognized from their ability to self‐renew and differentiation into multiple lineages. MSCs have promised a vast therapeutic potential in treatment many diseases including tissue injury and immune disorders. However, their regenerative potential profoundly depends on patients’ age. Age‐related deterioration of MSC is associated with cellular senescence mainly caused by increased DNA methylation status, accumulation of oxidative stress factors and mitochondria dysfunction. We found that DNA methyltransferase (DNMT) inhibitor i.e. 5‐Azacytidine (5‐AZA) reversed the aged phenotype of MSCs. Proliferation rate of cells cultured with 5‐AZA was increased while the accumulation of oxidative stress factors and DNA methylation status were decreased. Simultaneously the mRNA levels of TET proteins involved in demethylation process were elevated in those cells. Moreover, cells treated with 5‐AZA displayed reduced reactive oxygen species (ROS) accumulation, ameliorated superoxide dismutase activity and increased BCL‐2/BAX ratio in comparison to control group. Our results indicates that, treating MSCs with 5‐AZA can be justified therapeutic intervention, that can slow‐down and even reverse aged‐ related degenerative changes in those cells.     

Purification and Characterization of Glucose 6‐Phosphate Dehydrogenase, 6‐Phosphogluconate Dehydrogenase,and Glutathione Reductase from Rat Heart and Inhibition Effects of Furosemide,Digoxin, and Dopamine on the Enzymes Activities

The present study was aimed to investigate characterization and purification of glucose–6‐phosphate dehydrogenase, 6‐phosphogluconate dehydrogenase, and glutathione reductase from rat heart and the inhibitory effect of three drugs. The purification of the enzymes was performed using 2',5'‐ADP sepharose 4B affinity material. The subunit and the natural molecular weights were analyzed by SDS‐PAGE and gel filtration. Biochemical characteristics such as the optimum temperature, pH, stable pH, and salt concentration were examined for each enzyme. Types of product inhibition and K_i values with K_m and V_max values of the substrates and coenzymes were determined. According to the obtained K_i and IC₅₀ values, furosemide, digoxin, and dopamine showed inhibitory effect on the enzyme activities at low millimolar concentrations in vitro conditions. Dopamine inhibited the activity of these enzymes as competitive, whereas furosemide and digoxin inhibited the activity of the enzyme as noncompetitive.