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1.
High mobility group box 1 protein (HMGB1), a potent pro-inflammatory cytokine, contributes to the pathogenesis of diverse inflammatory and infectious disorders. Some studies have illustrated the potential effect of HMGB1 on regulatory T cells (Tregs). Astragaloside IV (AST IV) isolated from a Chinese herb, Astragalus mongholicus, is known to have a variety of immunomodulatory activities. However, it is not yet clear whether AST IV possesses potential regulatory effect on the pro-inflammatory ability of HMGB1 with subsequent activation of Tregs. This study was carried out to investigate the antagonistic effects of different doses of AST IV on the immune function of Tregs mediated by HMGB1 in vitro. Tregs isolated from the spleens of mice were co-cultured with HMGB1 and/or AST IV. Cell phenotypes of Tregs were analyzed, and the contents of various cytokines in the cell supernatants as a result of co-culture and the proliferation of CD4+CD25 T cells were determined. Results showed that HMGB1 stimulation resulted in significantly down-regulation of expressions of Tregs cell phenotypes. However, AST IV can rival the suppressing effect of HMGB1 on immune function of Tregs with a dose-dependent in vitro. These results indicate that AST IV has the potential therapeutic action on inflammation augmented by HMGB1.  相似文献   

2.
3种白刺耐盐性的对比分析   总被引:7,自引:5,他引:2       下载免费PDF全文
以2年生西伯利亚白刺、齿叶白刺和唐古特白刺苗为材料,设置0、100、200、300、400 mmol.L-1NaCl 5种盐浓度开展胁迫试验,测定并对比分析其对盐胁迫的生长及生理生化响应。结果表明:低盐浓度处理促使白刺生长速度和生物量增加、叶绿素含量增高,高盐浓度处理下这种促进作用降低;在100 mmol.L-1的盐处理下,唐古特白刺、西伯利亚白刺、齿叶白刺叶绿素含量均达最高,分别为0.72、0.78、0.61 mg.g-1;在400 mmol.L-1的盐处理下,唐古特白刺、西伯利亚白刺、齿叶白刺生物量为最低,分别为10.49、12.42、10.19 g.株-1,仅为对照的75%79%;3种白刺中,唐古特白刺的Na+/K+最高,施盐处理下西伯利亚白刺的Na+/K+均高于对照,而齿叶白刺则低于对照;随着盐浓度的增加,3种白刺叶片中可溶性蛋白的含量递增,可溶性糖含量则先增后减;低盐浓度处理的唐古特和西伯利亚白刺叶片中MDA含量比对照低,齿叶白刺却比对照高;3种白刺的POD和SOD活性在盐处理下高于对照,其中唐古特白刺叶片中POD活性最低,齿叶白刺中SOD活性最高;3种白刺在盐胁迫下均能正常生长。  相似文献   

3.
宽叶杜香叶柄再生体系建立及种质离体保存研究   总被引:1,自引:1,他引:1       下载免费PDF全文
The tender leafstalks of Ledum palustre var.dilatatum were used as explants for the experiment.Uniform design for the most suitable media for shoots regeneration immediately at base of tender leafstalks,rooting and germplasm conservation in vitro was screened.The results showed that N6+ZT 2.65 mg·L-1+IAA 0.05 mg·L-1 was fits for shoots regeneration,the frequency of shoots induction was higher than 92.5%;MS(modified)+IAA 0.1 mg·L-1+Kt 0.75 mg·L-1 for rooting,the rate of rooting was 98%;N-68+B9 2.5 mg·L-1+ Ph...  相似文献   

4.
Evidences have suggested that Tectona grandis (TG) attenuates gastric mucosal injury; however its mechanism has not yet been established. The aim of present study was to evaluate the gastroprotective mechanism of ethanolic extract of TG (E-EtOH), butanolic fraction (Fr-Bu) and to identify its active constituents. Anti-ulcer activities were evaluated against cold restraint (CRU) and pyloric ligation (PL) induced gastric ulcer models and further confirmed through H+ K+-ATPase inhibitory activity. Cytoprotective activity was evaluated in alcohol (AL) induced gastric ulcer model and further through PGE2 level. E-EtOH and Fr-Bu attenuated ulcer formation in CRU. Moreover E-EtOH and Fr-Bu displayed potent anti-secretory activity as evident through reduced free acidity and pepsin activity in PL, confirmed further by in vitro inhibition of H+ K+-ATPase activity. In addition cytoprotective potential of E-EtOH and Fr-Bu were apparent with protection in AL model, increased PGE2 content and enhanced mucin level in PL. Phytochemical investigations of Fr-Bu yielded terpenoides and a phenolic glycoside, verbascoside. The anti-secretory mechanism of verbascoside mediated apparently through inhibition of H+ K+-ATPase with corresponding decrease in plasma gastrin level, is novel to our finding. Gastroprotection elicited by TG might be through proton pump inhibition and consequent augmentation of the defensive mechanism.  相似文献   

5.
One new guaiane-type sesquiterpene (1) was isolated from Saussurea laniceps. The structure of the new compound was elucidated by spectroscopic data analysis. The immunomodulatory activity of compound 1 was evaluated. It was found that compound 1 showed significant inhibition for proliferation of murine T cells in vitro.  相似文献   

6.
为探究CDPK基因在木材形成过程中的作用,本研究在基因组水平上对杨树CDPKs基因家族的成员进行分析,找到32个CDPKs及10个CRKs成员。对CDPK基因家族成员在杨树中表达特性进行了分析,发现其家族成员在不同组织、不同发育阶段以及毛白杨次生维管发育不同时期的表达特性不同。分析杨树CDPK基因家族中3个基因Pt CPK1、Pt CPK6、Pt CPK15,其蛋白质一级结构均存在1个跨膜区,其蛋白定位在细胞膜上。  相似文献   

7.
为提高猴头菌菌株CB1锰过氧化物酶(MnP)基因的表达产量,采用PEG/CaCl2介导的原生质体转化方法,将携带有He-mnp1的重组质粒pLB01/He-mnp1转入到构巢曲霉尿嘧啶尿苷营养缺陷菌株TN02A7的原生质体中,获得了转化子菌株TN02A7-He-mnp1,并在乙醇脱氢酶启动子alcA(p)控制下实现了异源表达。将TN02A7-He-mnp1、TN02A7、构巢曲霉野生型菌株WJA01、猴头菌菌株CB1在相同的木质素环境下进行培养并检测MnP酶活性,结果表明:转化子菌株TN02A7-He-mnp1在0.05 g.L-1血红素的情况下、诱导96 h后酶活性最高为38.31 U.L-1,比不添加血红素的酶活力高8.64倍,但比猴头菌菌株CB1的酶活力低,而TN02A7与WJA01始终无MnP酶活性,说明基因He-mnp1已经成功地被转化到TN02A7-He-mnp1中,并在木质素环境下得到表达,血红素是重组MnP基因异源表达的限制性因素之一。本文为生产MnP和提高MnP产量提供了新的途径。  相似文献   

8.
卷荚相思组培快繁技术研究   总被引:1,自引:0,他引:1       下载免费PDF全文
[目的]建立16年生卷荚相思优树组培快繁技术体系。[方法]以16年生卷荚相思优树的当年新生枝条带腋芽茎段为材料,对卷荚相思外植体进行消毒、初代培养、增殖培养、生根培养和移植等。[结果]表明:通过对16年生卷荚相思成年优树采条进行扦插,以扦插苗建立采穗圃,选取采穗圃中当年生健康无病虫害枝条的中段为外植体,最佳消毒方式为75%的酒精处理0.5 min和0.1%的升汞处理18 min,其存活率达69.33%,芽诱导率达86.67%;最佳初代培养基为改良MS+蔗糖40 g·L-1,出芽率为91.33%。最佳增殖培养基为MS+6-BA 0.5 mg·L-1+NAA 0.1 mg·L-1+蔗糖30 g·L-1,35 d增殖倍数可达3.50倍;最佳生根培养基为1/2 MS+IBA 0.25 mg·L-1+NAA 0.5 mg·L-1+蔗糖40 g·L-1,15 d生根率为96.11%;将生根苗移植至以沙为基质的营养杯中,存活率为71.11%。[结论]研究解决了16年生卷荚相思成年优树外植体污染率高和芽诱导率低等问题,建立的组培快繁技术体系对今后加快卷荚相思良种选育及优质苗木大量扩繁具有重要作用。  相似文献   

9.
Significant increases in aboveground biomass production have been observed when Eucalyptus is planted with a nitrogen-fixing species due to increased nutrient availability and more efficient use of light. Eucalyptus and Acacia are among the most popular globally planted genera with the area of Eucalyptus plantations alone expanding to over 19 Mha over the past two decades. Despite this, little is known about how nutrition and light availability in mixed-species tree plantations influence water use and water use efficiency (WUE). This study examined to what extent water use and WUE have been influenced by increased resource availability and growth in mixed-species plantations. Monocultures of Eucalyptus globulus Labill. and Acacia mearnsii de Wildeman and 1:1 mixtures of these species were planted. Growth and transpiration were measured between ages 14 and 15 years. Aboveground biomass increment (Mg ha−1) was significantly higher in mixtures (E. globulus; 4.8 + A. mearnsii; 0.9) than E. globulus (3.3) or A. mearnsii monocultures (1.6). Annual transpiration (mm) measured using the heat pulse technique was also higher in mixtures (E. globulus; 285 + A. mearnsii; 134) than in E. globulus (358) and A. mearnsii (217) monocultures. Mixtures exhibited higher WUE than monocultures due to significant increases in the WUE of E. globulus in mixtures (1.69 kg aboveground biomass per cubic metre water transpired) compared to monocultures (0.94). The differences in WUE appear to result from increases in canopy photosynthetic capacity and above- to belowground carbon allocation in mixtures compared to monocultures. Although further studies are required and operational issues need to be resolved, the results of this study suggest that mixed eucalypt–acacia plantations may be used in water-limited environments to produce a given amount of wood with less water than eucalypt monocultures. Alternatively, because mixtures can be more productive and use more water per unit land area (but use it more efficiently), they could be utilized in recharge zones where rising water tables and salinity result from the replacement of vegetation (fast growing trees) that uses higher quantities of water with vegetation (shallow rooted annual crops) that use lower quantities of water.  相似文献   

10.
本研究从日本落叶松中克隆到一个谷胱苷肽还原酶(GR)基因,命名为LaGR。该基因编码563个氨基酸组成的蛋白质,预测分子量为61.06 kDa。表达模式分析发现LaGR基因在芽、成熟针叶、茎韧皮部和根韧皮部均表达,是组成型表达基因。蛋白质亚细胞定位研究发现LaGR蛋白定位在叶绿体。在大肠杆菌中表达并纯化了LaGR重组蛋白。酶学性质分析发现,LaGR蛋白对底物GSSG和NADPH具有较高的催化活性和亲和力,是热稳定蛋白,而且最适pH值范围在7.0 9.0之间。Cd2+、Pb2+和Cu2+等重金属离子对LaGR蛋白的催化活性具有明显的抑制作用。将LaGR蛋白的第528位His突变为Gln后,其突变蛋白的催化活性显著降低,而且与野生型LaGR蛋白相比,突变蛋白的动力学常数、最适pH值范围和热稳定性均发生了显著变化,预示着第528位的His在LaGR的催化特性和蛋白结构稳定性方面发挥着重要作用。  相似文献   

11.
This study examined the analgesic and anti-inflammatory actions of cis-mulberroside A isolated from Ramulus mori in several models of inflammatory pain in mice. Cis-mulberroside A (25 and 50 mg/kg) given by p.o. route 30 min before challenge produced a dose-dependent inhibition of the acetic acid-induced pain and Evans blue leakage in mice. In addition, this compound exhibited significant systemic anti-inflammatory activity in carrageenan-induced mouse paw edema in a concentration-related manner (33.1–68.5% inhibition), and similar results were achieved in formalin test. Suppressive effects of cis-mulberroside A on the production of NO and expression of inducible nitric oxide synthase (iNOS) in lipopolysaccharide (LPS)-stimulated macrophages were also assessed. Collectively, cis-mulberroside A showed high analgesic and anti-inflammatory activities. The above results will be the supporting evidence for the potential anti-rheumatoid activity of R.mori in Chinese traditional medicine.  相似文献   

12.
以白花泡桐优树‘白优2号’为试验材料,通过组织培养和试管嫁接方法,对白花泡桐优树材料的幼化技术进行了研究.结果表明:外植体初代培养萌发的嫩芽为最适合的接穗;‘建始桐3号’为试管嫁接较合适的砧木;采用劈接进行;MS+ NAA0.3 mg·L-1+蔗糖30 g·L-1为试管嫁接培养基;继代增殖和生根培养基分别为1/2MS ...  相似文献   

13.
Annona squamosa (AS) has traditionally been used as ethnomedicine. We have earlier extracted and fractionated the twigs of AS based upon its bioactivity and observed its immune potentiating activity that was localized in its three fractions. Present communication deals with the phytochemical analysis and pharmacological investigation of the most active chloroform fraction that led to isolation and identification of a number of compounds whose structures were elucidated using 1D and 2D NMR spectroscopic analysis. Amongst the twelve pure compounds isolated, five compounds Lanuginosine (1), (+) -O- methylarmepavine (2), (+)-anomuricine (3), Isocorydine (4), and N-methyl-6, 7-dimethoxyisoquinolone (5) were evaluated in vivo for their immune modifier activities in BALB/c mice after oral administration at three log doses of 0.3, 1.0 and 3.0 mg/kg for 14 consecutive days. Of these, three compounds (1, 2 and 5) showed dose dependent immune stimulating activity. However, the uppermost activity was noted in the compound N-methyl-6, 7-dimethoxyisoquinolone at the 3.0 mg/kg oral dose. The activity was assessed in the form of increased splenic T and B cellular proliferation, up-regulated CD4+, CD8+ and CD19+ cell population and accentuation in the peritoneal macrophage function. The compound possibly acted modifying the expression of Th1- and Th2- cytokines via stimulation of pro-inflammatory Th1 cytokines IL-2 and IFN-γ. These results warrant the use of the above compounds as an efficient immune-stimulant or immune-adjuvant against diseases with immune suppression. The analogs of the compound may further be chemically synthesized to achieve desired immune modifying activity.  相似文献   

14.
We used an isotopic approach to evaluate the effects of three afforestation methods on the ecophysiology of an Aleppo pine plantation in semiarid Spain. The site preparation methods tested were excavation of planting holes (H), subsoiling (S), and subsoiling with addition of urban solid refuse to soil (S + USR). Five years after plantation establishment, trees in the S + USR treatment were over three times larger than those in the S treatment, and nearly five-fold larger than those planted in holes. Differences in tree biomass per hectare were even greater due to disparities in initial planting density and pine tree mortality among treatments. Pine trees in the S + USR treatment showed higher foliar P concentration, δ13C and δ15N than those in the S or H treatments. Foliar δ15N data proved that trees in the S + USR treatment utilized USR as a source of nitrogen. Foliar δ13C and δ18O data suggest that improved nutrient status differentially stimulated photosynthesis over stomatal conductance in the pine trees of the S + USR treatment, thus enhancing water use efficiency and growth. In the spring of 2002, trees in the S + USR treatment exhibited the most negative predawn water potentials of all the treatments, indicating that the rapid early growth induced by USR accelerated the onset of intense intra-specific competition for water. The results of this study have implications for the establishment and management of Aleppo pine plantations on semiarid soils. Planting seedlings at low density and/or early thinning of pine stands are strongly recommended if fast tree growth is to be maintained beyond the first few years after USR addition to soil. Foliar C, O and N isotope measurements can provide much insight into how resource acquisition by trees is affected by afforestation techniques in pine plantations under dry climatic conditions.  相似文献   

15.
Two new triterpenoids (1, 2), together with one flavonoid glycoside and thirteen known triterpenoids were isolated from the roots of Actinidia chinensis Planch (Actinidiaceae). The structures of the new constituents were elucidated as 12α-chloro-2α, 3β, 13β, 23-tetrahydroxyolean-28-oic acid-13-lactone (1), 2α, 3α, 19α, 23, 24-pentahydroxyurs-12-en-28-oic acid (2). Structure elucidation was accomplished by 1D, 2D NMR spectra (HMQC, HMBC, 1H-1H COSY, TOCSY, and NOESY) and mass spectrometry (ESIMS). Moreover, two known triterpenoids showed positive cytotoxic activity against LOVO and HepG2 cell lines.  相似文献   

16.
This study was aimed to clarify the mechanism of gastroprotection by Vanillosmopsis arborea Baker essential oil (EOVA) using ethanol-induced gastric mucosal damage in mice. Gastric lesions were significantly reduced by EOVA (200 and 400 mg/kg). Chemical analysis showed that the major compound of EOVA was α-bisabolol. Pretreatment of mice with yohimbine, the α2-antagonist, greatly suppressed the gastroprotective effect of OEVA. Furthermore, OEVA gastroprotection was not attenuated in mice pretreated with indomethacin, L-NAME or glibenclamide, the respective inhibitors of cyclooxygenase, nitric oxide synthase and K+ATP channel activation. These data suggest that OEVA affords gastroprotection most possibly by α2-receptor activation.  相似文献   

17.
Six new acylphloroglucinol derivatives, sampsonols A-F (16), were isolated from the petroleum ether extract of the aerial parts of Hypericum sampsonii. The structures and relative configurations of sampsonols A-F were elucidated by extensive spectroscopic analyses. All these compounds were tested for their in vitro cytotoxic and anti-inflammatory activities. Sampsonols A and B (1 and 2) showed significant cytotoxicity against four human tumor cell lines with IC50 values in the range of 13–28 μM, whereas sampsonols C and F (3 and 6) showed potent inhibitory activities against LPS-induced NO production in RAW 264.7 macrophages with IC50 values of 27.3 and 29.3 μM, respectively.  相似文献   

18.
19.
玫瑰(Rosa rugosa Thunb.)又称玫瑰花,是蔷薇科 (Rosaceae) 蔷薇属(Rosa L.)落叶灌木.该种为国家三级重点保护植物.<中国珍稀濒危保护植物名录(第一册)>中定为濒危种,<中国物种红色名录>定为易危种[1],<吉林省野生动植物保护管理暂行条例>中定其为省级一类重点保护植物.是待开发的野生珍稀濒危药用植物,花、果、根入药,主治吐血、痛经、咯血、乳痈、月经不调等症.该种玫瑰具有喜光,耐寒,耐贫瘠,抗风等特性,可防止高山苔原带的水土流失,对维护生态平衡,美化天池环境以及引种驯化、开发利用于作护坡保土、园林绿化和培育玫瑰新品种;对研究该属植物的系统发育与地理分布也有重要科学价值.玫瑰在长白山区数量非常稀少,仅在珲春市敬信乡有零星分布.近年来,由于旅游设施及道路的修建等人为因素的干扰,其生境遭到严重破坏.又因玫瑰的天然更新能力非常弱,其种子成熟度小,种子繁殖可操作性极差,插条繁殖生根率和移栽成活率也极低,使其开发及利用受到极大限制.因此,在保护好现有野生资源的同时,本研究以玫瑰新生嫩茎为外植体,利用植物组织培养方法,采用均匀设计法,以期筛选出玫瑰嫩茎离体培养各阶段的培养基.目前,与其同属的其他种植物的离体培养已有报道,但关于该种玫瑰植株再生体系的研究迄今未见.  相似文献   

20.
胸苷酸激酶是d TTP从头合成和补救途径的关键酶,催化d TMP形成d TDP,在DNA复制和生物的生存中发挥着必不可少的作用。本文在前期研究的基础上,对从泡桐丛枝(Pa WB)植原体中获得的的3个同源蛋白TMK-a-1、TMK-a-2及TMK-b与已报道的小麦蓝矮(WBD)、洋葱黄化(OY-W)植原体的TMK-a、TMK-b的氨基酸序列进行了比对和相似性分析,结果显示Pa WBPS TMK-b与WBD TMK-2和OY-W TMK-b之间的相似性分别为95.65%和99.03%;Pa WBPS TMK-a-1与Pa WBPS TMK-a-2的相似性为90.57%,且二者与WBD TMK-1和OY-W TMK-a之间的相似性为87.32%-94.26%;而Pa WBPS、WBD、OY-W三种植原体的TMK-a与TMK-b之间的相似性仅为22.22%-25.95%。构建了Pa WBPS TMK-b、TMK-a-1、TMK-a-2的p ET28a原核表达载体,对Pa WBPS TMK-b、TMK-a-1、TMK-a-2 3种蛋白进行了原核表达,经Ni-NTA柱纯化后,利用双酶法进行了胸苷酸激酶催化活性测定,结果表明,Pa WBPS TMK-b具有较高的胸苷酸激酶活性,为85.96±0.74 U·mg-1,而Pa WBPS TMK-a-1和TMK-a-2几乎没有胸苷酸激酶活性。本文为进一步研究胸苷酸激酶在植原体繁殖过程中的作用机理奠定了基础。  相似文献   

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