Toxicological effects of rare earth yttrium on wheat seedlings（Triticum aestivum）

This study examined the biochemical responses of wheat（Triticum aestivum） to the stress of rare earth yttrium（Y） and showed that 25–100 mg/kg Y treatments evidently increased the biomass（root mass,shoot mass and leaf mass）,accompanied by a significant（p0.05） increase in the chlorophyll（CHL） content in wheat leaves.Increased malondialdehyde（MDA） levels were detected in wheat shoots（stem and leaf） and roots too,indicating the presence of poisoning active oxygen species（AOS）.The MDA content in wheat roots increased with the augmentation of Y concentration.These results indicated that there was a dose-dependent effect of Y on the changes of MDA content in wheat roots.Although the activities of superoxide dismutases（SOD）,peroxidases（POD） and catalases（CAT） in wheat shoots and roots irregularly fluctuated with the increase in Y concentration,25–100 mg/kg Y significantly（p0.01） increased the activities of SOD and POD.In general,the dose-dependent effects of Y on the activity of antioxidant enzymes were insignificant.Our data also indicated that the increase in SOD and POD activities could be used as a good biomarker for the stress induced by low concentrations of Y.     

Alleviation Effect of Lanthanum on Cadmium Stress in Seedling Hydroponic Culture of Kidney Bean and Corn

Since1970s,rare earths(RE)have been exten-sively used as micro-fertilizers for crops in China.Ithas already been proved that REcani mprove the pro-duction and quality of crops.However,there havebeen a fewinvestigations about using RE as regulatorin pollution ecology.For example,An et al[1]studiedthe effects of O3on wheat growth and the protectiveeffect of RE.Yan and Zhou et al[2,3]discussed theprotective effect of RE on plants under acid rainstress.Jia et al[4]and Hu et al[5]reported th…     

Toxic Effects of Lanthanum, Cerium, Chromium and Zinc on Potamogeton Malaianus

iththerapiddevelopmentofrareearthindustryandextensiveapplicationofrareearthinagriculture ,agreatmanyofrareearthelements (REEs)werere leasedintoenvironment ,especiallywaterenviron ment ,andtheconsequentseriousenvironmentpollu tionhasattractedpeople′satten…     

Effect of La-Gly on Physiological and Biochemical Characteristics of Glycine max Seedling under Pb Stress

ＴｈｅｒｅｈａｖｅｂｅｅｎｓｏｍｅｒｅｐｏｒｔｓｏｎｔｈｅｍｅｃｈａｎｉｓｍｏｆｔｈｅｓｔｒｅｓｓｉｎｊｕｒｙｂｙＰｂｐｏｌｌｕｔｉｏｎｉｎｐｌａｎｔ[1～ 4] .ＴｈｅｉｎｊｕｒｙｕｎｄｅｒＰｂｓｔｒｅｓｓｗａｓｒｅｌａｔｅｄｔｏｔｈｅｄｅｓｔｒｏｙｏｆｓｕｐｅｒｍｉｃｒｏｓｔｒｕｃｔｕｒｅｏｆｃｅｌｌｎｕｃｌｅｕｓｅｓ,ｍｉｔｏｃｈｏｎｄｒｉｏｎ ,ｃｈｌｏｒｏｐｈａｓｔ[5] ,ｓｏｔｈａｔｔｈｅｃｏｎｔｅｎｔｓｏｆｔｈｅｃｈｌｏｒｏｐｈｙｌｌａｎｄａｓｃｏｒｂｉｃａｃｉｄ[1 ,4,5] ,ｔｈｅａｃｔｉｖｉ…     

Lanthanum Relieved Toxic Effects Caused by Nickel in Hydrocharis dubia B L. Backer Leaves

Rareearthelementshaveextensivelybiologicaleffectsonplants ,animalsandhumanbeingsinthebiosphere[1,2 ] .Researchershavefoundthatrareearthelementscouldpromotetheresistanceofplantagainstsalt[3] ,inundation[4 ] ,aridity[5] andacidrain[6 ] etal .However ,fewreportswereontheirabilityofrelievingthestressofheavymetaltotheplant .Lanthanum(La) ,asanimportantrareearthelement ,alwayspar ticipatesinorinterfereswiththeprocessofbiologicalreactions[7] .ThispapermainlydealtwiththeeffectsofLaonHydrocharisdubia…     

Effect of Lanthanum on Rice Growth and Physiological Parameters with Split-Root Nutrient Solution Culture

Ａｌｏｔｏｆｗｏｒｋｈａｓｂｅｅｎｄｏｎｅｏｎｔｈｅｅｆｆｅｃｔｏｆｒａｒｅｅａｒｔｈｅｌｅｍｅｎｔｓｏｎｐｌａｎｔｇｒｏｗｔｈａｎｄｐｈｙｓｉｏｌｏｇｉｃａｌａｃｔｉｖ ｉｔｉｅｓ .ＲｅｓｕｌｔｓｈａｖｅｓｈｏｗｎｔｈａｔＲＥＥｓａｐｐｌｉｅｄｂｙｆｏｌｉａｒｓｐｒａｙｓ ,ｓｅｅｄｔｒｅａｔｍｅｎｔｓｏｒａｄｄｉｔｉｏｎｔｏｔｈｅｓｏｉｌｓａｎｄｓｏ ｌｕｔｉｏｎｍｅｄｉａｃａｎｉｎｃｒｅａｓｅｇｒａｉｎｃｒｏｐｓ ,ｅｃｏｎｏｍｉｃｃｒｏｐｓ ,ａｎｄｖｅｇｅｔａｂｌｅｓｂｙ 5 0 %～ 12 % ,8 0 %…     

Effects of La^3＋ on ATPase Activities of Plasma Membrane Vesicles Isolated from Casuarina Equisetifolia Seedlings under Acid Rain Stress

Asamainkindofmembranetransporter ,plasmamembraneATPasesfacilitatethetransportofminerals ,sugars,metabolites ,andothercompoundsacrossthemembraneofthecells ,onlybywhichcouldplantcellscommunicatewithenvironmenttotransfersubstanceandinformation ,whichisessentialforplantgrowthandcellularhomeostasis[1] .Astheexperimentmateri als ,thehighlypurifiedplasmamembranevesiclesfromCasuarinaequisetifoliaseedlingscultivatedunderartificialacidrainstress ,wereisolatedbyaqueoustwo-phasepartitioningmethods .Thest…     

Nitric Oxide Alleviates Oxidative Stress Caused by Lanthanum in Rice Leaves

The effect of NO on lanthanum-induced antioxidant activities in rice was evaluated. The results showed that the uptake and translocation of La from root to shoot were obviously inhibited by 10μmol·L^-1 sodium nitropmsside （SNP）, a donor of NO, in the seedlings grown in Mura B nutrient solution with 100μmol·L^-1 La. Although the content of ascorbate acid （AsA） were scarcely affected by La or NO in our experiment, La decreased significantly the activity of SOD and content of GSH, while promoted H202 content in leaves. Furthermore, NO blocked these La effects. Taken together, the results suggested that NO relieved La toxicity in rice. A possible role for NO effects on antioxidant activity was discussed.     

Effect of Lanthanum on Disease Resistance Related Enzymes of Rape

Thegrowthandtheabilitytoresistdiseaseofcropscanbeincreasedbyrareearthelements (REEs)ofsuitableconcentration[1,2 ] .ReportsshowedthatsprayingREEscandecreasethediseaseindexesofin fectedplants .Zhangetalfoundthatthegrowthofapathogenofrapeformingsclerotium (Sclerotiniascle rotiorum )couldbeinhibitedbyREEsofacertaincon centration[3] .ButonlyafewreportshavestudiedthemechanismofthediseaseresistanceinducedbyREEs.EspeciallytheactivityofenzymesrelatedtodiseaseresistanceaffectedbyREEs ,aswellasthe…     

Effect of Lanthanum （Ⅲ） on Reactive Oxygen Metabolism of Soybean Seedlings under Supplemental UV-B Irradiation

The effect of lanthanum （Ⅲ） on reactive oxygen metabolism of soybean seedlings under elevated ultraviolet-B radiation（UV-B：280~320 nm）at 0.15 and 0.45 W·cm-2 levels respectively was studied through hydroponics in the laboratory.Plasmolemma permeability and contents of malonadialdehyde（MDA）,hydrogen peroxide（H2O2）,and proline gradually increased during the imposition of UV-B radiation and subsequently decreased during recovery from UV-B stress.The dynamic tendency of catalase（CAT）activity was similar to that of the above four indices.The activity of peroxidase（POD）initially increased,then remained at a high level,and finally dropped steeply when soybean seedlings were exposed to a low dosage of UV-B radiation.However,POD activity rose throughout and declined slightly on the eleventh day when soybean seedlings were stressed by a high dosage.With the addition of La （Ⅲ） of 20 mg·L-1,the rising tendency of plasmolemma permeability and contents of MDA,H2O2,and proline were slowed down during the stress period,whereas the declining speed was accelerated during the recovery period.The activities of CAT and POD were higher than those without La （Ⅲ） in all experiments.It suggested that the regulative effect of La （Ⅲ） on antioxidant enzymes such as CAT and POD could strengthen their capacities to scavenge reactive oxygen species（ROS）,decrease contents of MDA and proline,and maintain normal plasmolemma permeability.Further more,the protective potential of La （Ⅲ） was better under low UV-B radiation than under a high one.     

Effect of Neodymium on Physiological Activities in Oilseed Rape during Calcium Starvation

The effects of RE on increasing crop productivity and stress tolerance were reported inpast years[' '2). La ion acts as a calcium-influxinhibitor by displacing Ca2 from cell wallsand occupying Ca2 -binding sites on the plasmalemma, as effective as Ca in the deferral ofsenescence. Besides blocking calcium channels, La has been frequently reported to mimicCa2 effect on plant ion transport. Migliaccioet al. found that both Ca2 and La3 stimulated auxin uptake into pea epicotyl segmentsfr…     

Toxicological effects and risk assessment of lanthanum ions on leaves of Vicia faba L.seedlings

Vicia faba L.seedlings were hydroponically cultivated in 0-12 mg/L of extraneous lanthanum(La) for 15 d to investigate ecotoxicological effects and risk assessment of rare earth elements(REEs).The results showed that reactive oxygen species(ROS) production suchas superoxide radical(O2.-) and hydrogen peroxide(H2O2) were overproduced at higher concentrations of La,resulting in oxidatively modified proteins and shoot growth retardation.While,superoxide dismutase(SOD),catalase(CAT),ascorbate peroxidase(APX) and guaiacolperoxidase(GPX) isoenzymes were elevated to some extent to eliminate excess of ROS.HSP70 production and endopeptidase isoenzymeswere also enhanced,which were involved in repairing or degradation of the oxidatively modified proteins due to La.Thus,the antioxidantisoenzymes,endoprotease isoenzymes and HSP70 worked cooperatively to alleviate the La-induced oxidative damage.The significant enhancement of CAT and APX isoenzymes and HSP70 could also be used as early bioindicators of La-polluted solution.The threshold doserange was firstly delimited as 1-2 mg/L of extraneous La,corresponding to 7.34-9.37 μg/g dry weight in the leaves.These results would behelpful to further understand the toxicological effects and possible mechanisms of REE(s) on crop seedlings.     

Influence of lanthanum level and interactions with nitrogen source on early development of Juglans nigra

Rare earth elements have been used for 30 years in Chinese agriculture to improve growth and yield. Numerous scientific studies have shown improvements in physiology, mineral nutrition, and growth, though deleterious effects may also occur. Very few studies have been performed on woody species. We exponentially fertilized one-year old black walnut (Juglans nigra L.) seedlings with 0, 0.1, 1, 10, or 100 mg lanthanum (La) and 800 mg nitrogen (N) as NaNO3, (NH4)2SO4, NH4NO3, or no N. One month following final fertilization, growth, mineral nutrition, photosynthesis, chlorophyll, and nitrate reductase activity were assessed. Plants fertilized with the highest level of La had reduced fine root growth, concentrations of magnesium, calcium, nickel, and phosphorus, photosynthesis levels, and chlorophyll a content. Foliar La concentration showed an interaction effect, with three to four times greater concentration in plants fed at 100 mg La to those given 10 mg La for (NH4)2SO4 and NH4NO3 treatments. The results suggested no beneficial effects of La addition at levels used in this study and interactions between N source and La levels did not have an important impact on the growth, mineral nutrition, or physiology of black walnut seedlings.     

Effects of chitosan-RE³⁺-bentonite on growth of Chlorella vulgaris

Bentonite was modified with chitosan and REIs(La3+,Ce3+) to form chitosan-RE3+-bentonite(CRB) . CRB were characterized by DSC and FT-IR. And the inhibitory effects of CRB on the growth of Chlorella vulgaris were investigated. The results indicated that CRB could inhibit the growth of Chlorella vulgaris. The relative conductivity and the generation of malondialdehyde(MDA) increased. In addition,the superoxide dismutase(SOD) and peroxidase(POD) activities decreased. So CRB could be a promising algaecide agent.     

Antioxidative Capacity of Irbesartan

The author investigated the antioxidant effect of irbesartan[2-butyl-3-({4-[2-(2H-1,2,3,4-tetrazol-5-yl)phenyl]phenyl}methyl)-1,3-diazaspiro[4.4]non-1-en-4-one],an angiotensin receptor biocker(ARB),on the oxidation of erythrocytes induced by 2,2-[azobis(2-amidinopropane)hydrochloride](AAPH)and H2O2.The value of half concentration(IC50)of irbesartan to scavenge radicals was measured by reacting it with 2,2-[azinobis(3-ethylbenzothiazoline-6-sulfonate)radical cation](ABTS+).Activities of the catalase(CAT),superoxide dismutase(SOD),glutathione peroxidase(GSH-Px)and the content of malondialdehyde(MDA)in liver tissue and blood serum of normal-rats were measured by means of spectrophotometry to study the antioxidation function of irbesartan.Results of experiments show that irbesartan can scavenge ABTS+ and superoxide radicals effectively as well as inhibit AAPH-,H2O2-induced hemolysis of erythrocytes,Irbesartan can also increase the activities of GSH-Px,SOD,CAT and decrease the content of MDA of normal rats.So irbesartan is a good antioxidant.     

Effects of Lanthanum on Redox Systems in Plasma Membranes of Casuarina equisetifolia Seedlings Under Acid Rain Stress

Theplasmamembraneisapenetrablebarrier ,whichcancontroltheexchangeofsubstancesacrossmembranesincells ,andalsoistheintermediumandreceptorofenergyorinformationtransferencebetweencellsandenvironment.Theplasmamembraneredoxsystem(PMRS)meanstheelectrontransferchainsonplasmamembrane .Owingtohavethepossibilityofejectingprotons ,energizingplasmamembraneandhavingthefunctionofacceleratingtransportationofsoluteacrossmembrane ,theplasmamembraneredoxsystemswerepaidmuchattentionto[1] .Acidrainisoneofthemost…     

Toxic Effect of Cd^2＋ on Potamogeton crispus Alleviated by Exogenous Nd^3＋

Cadmiumis non-nutrition element for the plantgrowth,it can cause potential threat to the environ-ment safety as it remains in the nature for a very longti me,and once its concentrations reach or exceed acertainthreshold value,it will interfere withthe met…     

Effects of Lanthanum on Root Growth and Senescence of GF43 （ Prunus domestica ） Plantlet in Vitro

The effect and the action mechanism of lanthanum on GF43 plantlet in vitro were studied. The results of experiments show that root growth rate and dry weight of GF43 by LaCI3 treatments increase. The activities of antioxidant enzymes in root system such as superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD) apparently enhance. Moreover O^-2 and malond ialdehyde (MDA) contents and cell membrane permeability of GF43 are decreased by LaC13. The relatively stable membrane structure of cell could also be maintained and the root ageing of GF43 plantlet in vitro delays.     

A multicenter, investigator-blinded, randomized comparison of oral levofloxacin and oral clarithromycin in the treatment of acute bacterial sinusitis

The effects of Vitamin E administration on antioxidant enzyme activities and nitrite-nitrate levels of the reperfused rat kidney tissues were investigated by performing a 60 min ischemia followed by 24 and 72 hours of reperfusion. Vitamin E administration or the placebo (SF) was applied as 100 mg/kg BW. As expected, catalase (CAT) (p<0.05) and superoxide dismutase (SOD) (p<0.05) activities of ischemia/reperfused (I/R) kidney tissue were lower and malondialdehyde (MDA) levels were higher than control kidneys in both SF and vitamin E treated groups following 24 h reperfusion. During reperfusion of long term (72 h), vitamin E triggered a decrease in the MDA levels in the ischemic tissue, while it did not provoke a significant effect on SOD and catalase activities. Total nitrite levels of ischemic tissues in both of the groups were higher than matched control kidneys and this elevation was more clear in the vitamin E treated group. Our results showed that vitamin E has a protective effect on I/R injury, by a direct chain breaking effect on lipid peroxidation (LPO) and hence preventing the nitric oxide (NO) reservoir of ischemic tissue. Alfa-tocopherol may be a promising agent for the prevention of tissue injury caused by free oxygen radicals.     

Effect of NdCl_3 on the Injury of Membrane and ABA Content under Osmotic Stress

ＥｆｆｅｃｔｏｆＮｄＣｌ_３ｏｎｔｈｅＩｎｊｕｒｙｏｆＭｅｍｂｒａｎｅａｎｄＡＢＡＣｏｎｔｅｎｔｕｎｄｅｒＯｓｍｏｔｉｃＳｔｒｅｓｓ￥ＡｎＪｉａｎｐｉｎｇ（安建平）（ＢｉｏｌｏｇｙＤｅｐａｒｔｍｅｎｔ，ＴｉａｎｓｈｕｉＮｏｒｍａｌＣｏｌｌｅｇｅ，Ｔｉ?..