GnIH通过p38MAPK信号通路对猪卵巢颗粒细胞自噬与凋亡的影响

【目的】细胞自噬和凋亡存在着相互制约,p38MAPK信号通路作为细胞凋亡的主要调控通路之一,也对细胞自噬存在促进和抑制的双重作用。已有研究表明,促性腺激素抑制激素(gonadotropin-inhibitory hormone , GnIH)对细胞自噬与凋亡均有影响,但作用机制尚不明确。故探究GnIH通过p38MAPK信号通路对猪卵巢颗粒细胞（pGCs）自噬与凋亡的影响及其机理,为解决母猪的产子率以及同期发情等问题提供参考。【方法】min、10 min、30 min、60 min、90 min)分组,用Western blot检测猪卵巢颗粒细胞p38与p-p38的蛋白表达量变化;2、验证GnIH对p38MAPK信号通路的影响：按（空白对照、GnIH、p38激活剂（U-46619）、U-46619+GnIH）分组,用Western blot检测p38与p-p38的蛋白表达量变化;3、探究不同浓度GnIH对自噬和凋亡的影响：按（空白对照、10 ^-6mol·L ^-1 GnIH、10 ^-8mol·L ^-1 GnIH、10 ^-10mol·L ^-1 GnIH、10 ^-12mol·L ^-1 GnIH）分组,用Western blot检测自噬与凋亡标志性蛋白的表达量变化;4、验证不同浓度GnIH通过p38信号通路对自噬和凋亡的影响：将细胞分成6组（空白对照、U-46619、U-46619+10 ^-6 mol·L ^-1 GnIH、U-46619+10 ^-8mol·L ^-1 GnIH、U-46619+10 ^-10mol·L ^-1 GnIH、U-46619+10 ^-12mol·L ^-1 GnIH）,用Western blot检测自噬与凋亡标志性蛋白的表达量变化。【结果】1. GnIH孵育10 min后,显著降低p38与p-p38的蛋白表达量（P<0.05）,提示,GnIH对p38MAPK信号通路的最佳作用时间为10 min;2. U-46619显著促进pGCs的p38磷酸化水平（P<0.05）,GnIH显著抑制pGCs的p38磷酸化水平（P<0.05）,提示,U-46619使p38MAPK信号通路活化,GnIH对p38MAPK信号通路的活化有抑制作用;3. 当 GnIH的浓度为10 ^-6 mol·L ^-1时,pGCs的自噬和凋亡水平显著升高（P<0.05）,随着GnIH浓度的降低,pGCs的自噬水平逐渐升高（P<0.05）,pGCs的凋亡水平逐渐降低（P<0.05）,提示,高浓度GnIH可以促进自噬和凋亡,随着GnIH浓度的降低,自噬水平逐渐升高,而凋亡水平逐渐下降;4. 加入U-46619后,GnIH使pGCs的自噬显著上调（P<0.05）,并且使pGCs的凋亡显著下调（P<0.05）,提示,不同浓度GnIH通过p38MAPK信号通路影响pGCs的自噬和凋亡。【结论】GnIH可能通过抑制p38MAPK信号通路的活化,上调pGCs的自噬,减少pGCs的凋亡。     

黄芩苷通过上调miR-126诱导乳腺癌细胞凋亡的机制研究

目的 用黄芩苷干预人乳腺癌细胞株MDA-MB-231,观察黄芩苷对乳腺癌细胞增殖、凋亡的影响及作用机制。方法 用qRT-PCR检测miR-126的表达变化,Western-blot检测Bcl-2、Caspase-9、Caspase-3、p-p38和p53的表达,MTT法检测细胞增殖,流式细胞术检测细胞凋亡。结果 miR-126在乳腺癌MDA-MB-231细胞中的表达比正常乳腺细胞低,黄芩苷干预乳腺癌细胞后miR-126上调最为明显（P<0.05）。用miR-126 mimics、miR-126 inhibitors转染乳腺癌细胞,Western-blot显示黄芩苷及miR-126 mimics作用于人乳腺癌细胞后Bcl-2表达水平下降,Caspase-9和Caspase-3的裂解产物、p-p38、p53表达增加,差异有统计学意义（P<0.05）。MTT法显示黄芩苷和miR-126 均可抑制乳腺癌细胞的增殖,流式细胞术显示黄芩苷与miR-126 mimics促进癌细胞凋亡。结论 黄芩苷可以抑制乳腺癌细胞的增殖,促进其凋亡,其机制可能与通过上调miR-126调节凋亡相关基因有关。     

2-辛亚砜-5,8-二甲氧基-1,4萘醌通过ROS/Akt通路诱导HepG2细胞凋亡

为研究修饰后的萘醌类衍生物对人肝癌细胞株HepG2诱导细胞凋亡作用及其机制。采用MTT、流式和Western blot方法观察2-辛亚砜-5,8-二甲氧基-1,4萘醌对人肝癌细胞的生长作用。结果表明:2-辛亚砜-5,8-二甲氧基-1,4萘醌可通过促进早期ROS水平升高,抑制Akt的磷酸化水平,并选择性地激活p38,ERK信号通路,从而抑制肝癌细胞株HepG2细胞的增殖并诱导其发生凋亡。     

Promotion and Inhibition of Ruminal Epithelium Growth by Butyric Acid and Insulin-Like Growth Factor-1 (IGF-1) in Dairy Goats

Isolated ruminal epithelia from caudal blind sacs of dairy goats were incubated with butyrate and insulin-like growth factor-1 (IGF-1) at different concentrations. Proportions of ruminal epithelium in different phases of the cell division cycle were determined by flow cytometric analysis. The proportion of epithelial cells in S phase and G₂-M phase (P_S&G2-M) increased significantly (P<0.01) whereas the proportion of epithelial cells in G₀-G₁ phase (P_G0-G1) decreased after incubation with IGF-1. P_S&G2-M decreased whereas P_G0-G1 increased markedly (P<0.01) after incubation with sodium butyrate. P_S&G2-M incubated with IGF-1 and butyrate sodium together increased more than that incubated with IGF-1 alone; P_G0-G1, however, decreased significantly (P<0.01). Our results indicate that IGF-1 enhances whereas sodium butyrate inhibits the proliferation of rumen epithelial cells. Furthermore, butyrate and IGF-1, together, have a synergic effect on the proliferation of rumen epithelium.     

β-伴大豆球蛋白通过p38/JNK MAPK信号通路引起IPEC-J2细胞损伤

采用细胞体外培养技术,研究不同浓度7S(β-伴大豆球蛋白)对IPEC-J2(猪小肠上皮细胞)的影响。实验分为6组,A(对照组)、B(1 mg·mL^-1 7S)、C(5 mg·mL^-1 7S)、D(10 mg·mL^-1 7S)、E(5 mg·mL^-1 7S+1 μmol·L^-1 SP600125)、F(5 mg·mL^-1 7S+1 μmol·L^-1 SB202190),24 h后,用CCK-8法检测细胞存活率,收集细胞用ELISA法检测NO、5-HT、IL-6和IL-10含量,用Western blot法检测p-JNK、p-p38、Bcl-2蛋白表达量,用PCR法检测Bad、Bax、Bcl-2、Bcl-x_L和Caspase-3 mRNA相对表达量。检测结果表明:C组和D组的IPEC-J2细胞活性极显著降低(P<0.01),E组和F组的细胞活性显著高于C组(P<0.05),说明7S促进炎性细胞因子NO、5-HT和IL-6的分泌,降低IL-10的分泌,添加抑制剂使细胞因子NO、5-HT和IL-6分泌减少,IL-10的分泌增多;同时7S促进p-JNK、p-p38蛋白表达,降低Bcl-2蛋白表达,添加抑制剂可抑制p-JNK、p-p38蛋白表达,使Bcl-2蛋白表达增高。Bcl-2/Bax mRNA比值随7S浓度增加而降低,Bax/Bcl-x_l比值随7S浓度增加而升高,Caspase-3 mRNA相对表达量随7S浓度增加而升高。添加抑制剂后Bcl-2/Bax比值增高,Bax/Bcl-x_l比值降低,Caspase-3 mRNA降低。结果表明,7S通过p38/JNK MAPK信号通路引起仔猪肠上皮细胞损伤。     

基于p38 MAPK信号通路研究养阴润目丸治疗干眼兔的作用机制

目的 探讨基于p38 MAPK信号通路研究养阴润目丸治疗干眼兔的作用机制。方法 采用氢溴酸东莨菪碱皮下注射途径制备干眼兔模型,按随机数字表法分成模型组、p38抑制剂组、阳性药物（杞菊地黄丸）组和低、中、高剂量养阴润目丸组,同步设不造模的正常组,6只/组。各组按相应处理方式连续干预2周后,检测各组兔泪液分泌量、泪腺病理形态、泪腺组织凋亡细胞的表达及泪腺组织中p38 MAPK、Bax、Bcl-2蛋白和mRNA表达情况。结果 养阴润目丸组和阳性药物组能增加干眼兔模型泪液分泌量,抑制泪腺细胞的凋亡,下调p38 MAPK、Bax的蛋白和mRNA表达,上调Bcl-2的蛋白和mRNA表达水平,与模型组比较,差异均有统计学意义（P<0.05）。结论 养阴润目丸能够通过纠正Bax/Bcl-2失衡,改善干眼泪腺细胞凋亡,进而减轻泪腺细胞损伤,恢复泪腺细胞的代谢功能,与调控p38 MAPK的关系极为密切,这可能是其治疗干眼的重要机制之一。     

γ-亚麻酸在RAW264.7细胞中的抗炎症作用机制

[目的]探讨γ-亚麻酸（GLA）对脂多糖（LPS）诱导的RAW264.7细胞产生炎症介质的影响及其机制。[方法]以体外培养的巨噬细胞系RAW264.7细胞为研究对象,待细胞生长至融合状态后加入不同浓度（0、12.5、25、50μmol/L）的GLA预孵4 h,利用100 ng/m l的脂多糖（LPS）刺激12.0 h或0.5 h,同时设空白对照和LPS对照,利用蛋白印迹法检测诱生型一氧化氮合酶（iNOS）、环加氧酶-2（COX-2）蛋白的表达以及对IκBα、p-JNK/SAPK（Thr183/Tyr185）、p38 MAPK、p-p38 MAPK（Thr 180/Tyr182）、ERK1/2、p-ERK1/2的影响。[结果]GLA可以显著抑制LPS诱导的RAW264.7细胞中iNOS和COX-2的蛋白表达（P〈0.05）,且在0~50μmol/L GLA浓度范围内存在剂量依赖关系。GLA可以显著抑制IκBα的降解（P〈0.05）,从而抑制NFκ-B的激活。GLA可以显著抑制LPS诱导的JNK1/2以及ERK1/2的磷酸化（P〈0.05）,对p38的磷酸化没有显著影响。[结论]GLA具有很好的消炎功效。抑制JNK1/2和ERK1/2的磷酸化、抑制NF-κB的激活可能是GLA发挥生物学效应的重要机制。     

芦荟粉对西伯利亚鲟生长和血液生化指标的影响

以体重（23.5±3.6） g西伯利亚鲟（Acipenser baerii Brandt）为对象,研究芦荟粉对其生长和血液生化指标的影响。试验共分6个处理,处理G₁~G₅组芦荟粉的添加量分别为0、0.125%、0.250%、0.500%、1.000%,处理G₆组添加25 mg/kg大蒜素作为药物对照组。饲养期为56 d。试验结果表明,与G1和G6相比,饲料中添加芦荟粉对西伯利亚鲟增重率、特定生长率、饵料系数等无显著影响（P>0.05）;当饲料中芦荟粉的添加量为0.250%和0.500%时,血浆超氧化物岐化酶活力显著提高（P<0.05）;当饲料中芦荟粉的添加量为0.125%和0.250%时,血浆丙二醛含量显著降低（P<0.05）;饲料中添加0.250%~0.500%的芦荟粉可提高鱼体的抗氧化能力;饲料中添加芦荟粉对西伯利亚鲟血浆球蛋白、谷丙转氨酶活力、血糖、补体C3、补体C4、酸性磷酸酶活力、碱性磷酸酶活力等无显著影响（P>0.05）。     

Variations in chlorophyll content,stomatal conductance,and photosynthesis in Setaria EMS mutants

Chlorophyll (Chl) content, especially Chl b content, and stomatal conductance (G_s) are the key factors affecting the net photosynthetic rate (P_n). Setaria italica, a diploid C₄ panicoid species with a simple genome and high transformation efficiency, has been widely accepted as a model in photosynthesis and drought-tolerance research. The current study characterized Chl content, G_s, and P_n of 48 Setaria mutants induced by ethyl methanesulfonate. A total of 24, 34, and 35 mutants had significant variations in Chl content, G_s, and P_n, respectively. Correlation analysis showed a positive correlation between increased G_s and increased P_n, and a weak correlation between decreased Chl b content and decreased P_n was also found. Remarkably, two mutants behaved with significantly decreased Chl b content but increased P_n compared to Yugu 1. Seven mutants behaved with significantly decreased G_s but did not decrease P_n compared to Yugu 1. The current study thus identified various genetic lines, further exploration of which would be beneficial to elucidate the relationship between Chl content, G_s, and P_n and the mechanism underlying why C₄ species are efficient at photosynthesis and water saving.     

加味丹参饮抑制p38MAPK表达保护缺氧/复氧乳鼠心肌细胞损伤的实验研究

目的 观察加味丹参饮含药血清对缺氧/复氧（hypoxia/reoxygenation,H/R）乳鼠心肌细胞p38 MAPK蛋白表达的影响,以探讨其保护心肌的作用机制。方法 将20只SD乳鼠的心肌细胞进行原代培养,建立H/R模型并随机分为H/R组、SB203580（p38MAPK阻断剂组）、加味丹参饮含药血清组,正常心肌细胞组作为对照组。采用T淋巴细胞化学染色法鉴定心肌细胞,罗丹明B（Rhodamine B）染色法观察细胞形态,MTT比色法检测含药血清对乳鼠心肌细胞的毒性,Western-blot法检测MKK3（促分裂原活化蛋白激酶-激酶3）、MKK6（促分裂原活化蛋白激酶-激酶6）、p38MAPK、phospho-p38MAPK蛋白表达。结果 与正常血清对照组比较,H/R组MKK3、MKK6的蛋白表达增多,p38MAPK通路阻断剂SB203580和加味丹参饮均不能减少其表达;p38MAPK、phospho-p38MAPK在H/R时表达均增加（P<0.01）,而SB203580和加味丹参饮含药血清均能减少其表达（P<0.01）。结论 加味丹参饮含药血清预处理可通过抑制缺氧,复氧心肌细胞p38MAPK信号通路发挥保护作用,抑制p38MAPK表达及其磷酸化,减轻心肌细胞损伤,起到保护心肌细胞的作用。     

Relations Between Photosynthetic Parameters and Seed Yields of Adzuki Bean Cultivars (Vigna angularis

The study comparatively examined the leaf photosynthetic capacities of different adzuki bean cultivars, high-yield 2000-75 and Jihong 9218, and low-yield Hongbao 1 and Wanxuan 1 from flowering to ripening. It showed that after flowering, the leaves of the cultivars gradually aged, the leaf chlorophyll (Chl.), soluble protein (SP) contents, net photosynthetic rates (P_n), transpiration rates (T_r) and stomatal conductance (G_s) of the cultivars tended to decline, but the leaf intercellular CO₂ concentration (C_i) of the cultivars tended to rise. The leaf photosynthetic capacities of the cultivars decreased gradually from the lower to the upper nodes. The dry seed yields of the cultivars were positively correlated with their leaf Chl., SP, P_n, and T_r and G_s, and negatively associated with their leaf C_i. At the late growth stages, the high-yield cultivars maintained higher leaf Chl. contents, SP contents, P_n, T_r, and G_s than the low-yield cultivars, indicating that leaf photosynthetic capacity was one of important yield-affecting factors of adzuki bean. Therefore, it was important for a crop at the crucial stage of yield formation to maintain a high leaf chlorophyll content and a high leaf photosynthetic capacity and delay leaf aging.     

秸秆和硫酸铝对淡黑钙土有机矿质复合体及有机碳分布的影响

以吉林省典型土壤淡黑钙土为研究对象,采用室内恒温培养法研究在不同秸秆和硫酸铝添加量下,淡黑钙土中有机矿质复合体的含量及有机碳在其中的分布,探讨有机矿质复合体对淡黑钙土固碳的贡献。结果表明:对于秸秆和硫酸铝添加的所有处理,复合体含量均表现为G_1(钠分散组)G_0(水分散组)G_2(钠质研磨分散组);与对照相比,秸秆和硫酸铝添加使得淡黑钙土中G_0组复合体的含量降低,G_2组复合体的含量明显上升,而对G_1组复合体的含量影响不大。单位质量复合体中有机碳的含量大小表现为G_2G_0G_1,G_2组复合体中的有机碳含量最高(平均含量为95.92 g·kg~(-1)),约为单位质量G_0组和G_1组复合体中有机碳含量的3倍,G_0组(平均含量为33.89 g·kg~(-1))略高于G_1组(平均含量为32.25 g·kg~(-1))。秸秆和硫酸铝添加均有助于提高G_0组复合体中有机碳的含量;而G_1组复合体有机碳含量的变化主要受秸秆添加量的影响,随着秸秆添加量的增加,G_1组复合体有机碳含量增加;秸秆对G_2组复合体中有机碳含量的提高具有促进作用,而硫酸铝的影响则相反。各组复合体对淡黑钙土固碳的贡献率取决于土壤中复合体的含量及单位质量复合体中有机碳的含量,其对固碳贡献的大小顺序为G_1G_0G_2;有机矿质复合体(G_0+G_1+G_2)质量仅占淡黑钙土质量的约四分之一,但其对于淡黑钙土固碳的贡献却为61.96%~73.56%。     

低温胁迫时间对4种幼苗生理生化及光合特性的影响

以盐肤木(Rhus chinensis)、假连翘(Duranta repens)、老鸭嘴(Thunbergia erecta)和葛藤(Pueraria lobata)4种幼苗为试验材料,研究了人工模拟下的低温胁迫环境(6 ℃)对幼苗叶片生理生化及光合特性的影响。结果表明:(1) 随低温胁迫的延长,假连翘幼苗的叶绿素含量先升后降,其余3种幼苗持续下降,低温解除后均显著回升;4种幼苗的脯氨酸含量持续上升或波动;葛藤幼苗的可溶性蛋白质含量先升后降,其余幼苗显著上升, 且低温解除后有所增加;4种幼苗叶片可溶性糖含量以及丙二醛含量呈增加趋势,SOD活性持续上升或先升后降。低温解除后,盐肤木幼苗的SOD活性略有上升,其余幼苗显著下降。(2) 随低温胁迫的延长,4种幼苗的净光合速率(P_n)、气孔导度(G_s)、蒸腾速率(T_r)均持续下降,假连翘的胞间CO₂浓度(C_i)持续上升,其余幼苗先降后升。低温解除后4种幼苗叶片P_n、G_s、T_r均有不同程度的回升,C_i有不同程度的下降。低温胁迫和恢复48 h期间,4种幼苗的脯氨酸、可溶性糖、可溶性蛋白质含量的增加和SOD活性的稳定或增加,减轻了幼苗叶片细胞的膜脂过氧化程度, 维持了细胞膜的完整性,是幼苗对低温胁迫适应性反应的重要调节机制。恢复48 h时的P_n、G_s和Tr均有不同程度的回升,C_i有不同程度的下降,说明4种幼苗有一定的抗寒能力。(3)用主成分分析法分别对生理生化指标和光合生理指标进行分析,均得出4种幼苗的抗寒性顺序为葛藤>盐肤木>老鸭嘴>假连翘,这一结果可为采矿石废弃地生态恢复的植物筛选提供科学依据。     

两种高质牧草不同生育期光合生理日变化及光响应特征

于2010年5月25日(拔节、分枝期)、7月6日(抽穗、结荚期)、8月25日(开花期)晴朗天气,采用LI-6400便携式光合作用测定系统对新引1号东方山羊豆和柳枝稷各项光合生理生态指标进行了测定.结果表明:(1)新引1号东方山羊豆净光合速率(Pn)日变化呈双峰曲线,存在“光合午休”现象;分枝期Pn、光能利用效率(LUE)、水分利用效率(WUE)日均值高于结荚期,而结荚期的叶温(Tl)、蒸腾速率(Tr)、气孔导度(Gs)、胞间CO2浓度(Ci)日均值高于分枝期.(2)柳枝稷的Pn日变化呈单峰曲线,拔节期Pn、Tr日均值高于抽穗期,开花期最低;WUE与Ci日均值在开花期最高,拔节期次之,抽穗期最小;Tl、LUE日均值在抽穗期最高,拔节期次之,开花期最小.(3)Pn与Tr、Gs、叶片气孔限制值(Ls)、光合有效辐射(PAR)具有极显著正相关关系,与Ci呈极显著负相关;Tr与Gs、叶温下蒸汽压亏缺(Vpdl)、气温(Ta)、Tl、PAR均呈极显著正相关关系,与大气CO2浓度(Ca)呈显著负相关;Tl、Gs与PAR呈极显著正相关.(4)通过光响应曲线的绘制及相关生理指标的计算,结合相关评价标准,得出柳枝稷为阳生植物,而新引1号东方山羊豆为耐荫植物,且柳枝稷比新引1号东方山羊豆对光环境的适应性强.     

EM38 for volumetric soil water content estimation in the root-zone of deep vertosol soils

Electromagnetic induction sensors, such as EM38, are used widely for monitoring and mapping soil attributes via the apparent electrical conductivity (EC_a) of the soil. The sensor response is the depth-integrated combination of the depth-response function of the EM38 and ‘local’ electrical conductivity (EC_az) at depth. In deep, Vertosol soils, assuming the instrument depth-response function is not perturbed by the soil and where volumetric moisture content at depth (θ_v(z)) dominates EC_az, EM38 should be capable of predicting average moisture content without recourse to mathematically complicated, and unstable profile inversion processes. Firstly a multi-height EM38 experiment was conducted over deep Vertosol soils to confirm the veracity of the EM38 depth-response function and test the concomitant hypothesis of the EM38 response being an integrated (i.e. additive) combination of depth-response function and θ_v(z). Secondly, depth profiles of moisture content were used to calibrate the EM38 to infer average θ_v(z) within the ‘root-zone’ of crop plants—here taken to be surface—0.8 m and surface—1.2 m. EM38 calibration was performed using soil samples acquired from both extracted cores and excavated pits. Mathematical summation of measured θ_v(z) from sectioned cores and the known depth-response function of the EM38 was found to explain 99% and 97% of the variance in measured EC_a for horizontal and vertical dipole configurations at multiple sensor heights above the ground. Average θ_v from surface to 0.8 m () and surface to 1.2 m () explained only 37% and 46% of the variance in on-ground EC_a for vertical dipole configuration measurements compared to 55% and 56% of the variance for horizontal dipole configuration. In a separate validation experiment, the shape of the vertical moisture profile proved highly influential in determining the ability of the calibration equations to infer underlying average moisture content, especially where the depth profile shapes differed between sensor calibration and subsequent field validation (for example following rainfall or irrigation).     

Hydrogen Sulfide May Function Downstream of Nitric Oxide in Ethylene-Induced Stomatal Closure in Vicia faba L.

Pharmacological, laser scanning confocal microscopic (LSCM), and spectrophotographic approaches were used to study the roles of hydrogen sulfide (H₂S) and nitric oxide (NO) in signaling transduction of stomatal movement in response to ethylene in Vicia faba L. Ethylene treatment resulted in the dose-dependent stomatal closure under light, and this effect was blocked by the inhibitors of H₂S biosynthesis in V. faba L. Additionally, ethylene induces H₂S generation and increases L-/D-cysteine desulfhydrase (pyridoxalphosphate-dependent enzyme) activity in leaves of V. faba L. Inhibitors of H₂S biosynthesis have no effect on the ethylene-induced stomatal closure, NO accumulation, and nitrate reductase (NR) activity in guard cells or leaves of V. faba L. Moreover, the ethylene-induced increase of H₂S levels and L-/D-cysteine desulfhydrase activity declined when NO generation was inhibited. Therefore, we conclude that H₂S and NO probably are involved in the signal transduction pathway of ethylene-induced stomatal closure. H₂S may represent a novel component downstream of NO in the ethylene-induced stomatal movement in V. faba L.     

紫云英翻压条件下氮肥运筹对双季稻产量和肥料利用率的影响

在早稻-晚稻-紫云英轮作模式下,研究连续3年（2011-2013年）紫云英翻压还田下氮肥运筹对水稻增产效果、肥料利用率及经济效益的影响。本研究通过田间小区试验分析比较了紫云英翻压（G）下5种不同施氮模式（氮肥按照基肥/蘖肥/穗肥比例100/0/0、70/30/0、70/0/30、50/50/0、50/30/20分别设置G₁、G₂、G₃、G₄、G₅处理）及单施化肥配合氮肥运筹50/30/20比例（F₁）和不施肥处理（CK）共7种处理,对早、晚稻产量、产量稳定性及肥料利用率的影响。试验结果表明,在早稻施肥处理中,相同氮肥运筹G₅的早稻产量、产量稳定性和可持续性比F₁分别提高7.77%、33.47%和3.89%。在不同氮肥运筹之间,G₅和G₃均具有较高的早稻产量及产量稳定性。在晚稻中,G₅晚稻产量显著高于F₁,但产量稳定性和可持续性较差;对比5个氮肥运筹,G₅具有较高的晚稻产量和产量稳定性。相同氮肥运筹下,G₅的化肥偏生产力和化肥农学效率均高于F₁,整个轮作周期里分别提高9.35%和22.60%。折算经济效益,早稻各个处理之间经济收益相差不大,晚稻在G₅的施肥方式下经济效益最高。综合水稻产量、产量稳定性以及肥料利用率,在紫云英翻压条件下G₃和G₅分别是早稻和晚稻的最佳施肥方式。     

γ-亚麻酸在RAW264.7细胞中的抗炎症作用机制（英文）

[目的]探讨γ-亚麻酸（GLA）对脂多糖（LPS）诱导的RAW264.7细胞产生炎症介质的影响及其机制。[方法]采用体外培养的巨噬细胞系RAW264.7细胞,待细胞生长至融合状态后加入不同浓度（0、12.5、25、50μmol/L）的GLA预孵4h,利用100ng/ml的脂多糖（LPS）刺激12h或0.5h,同时设空白对照和LPS对照,利用蛋白印迹法检测诱生型一氧化氮合酶（iNOS）、环加氧酶-2（COX-2）蛋白的表达以及对IκBα、p-JNK/SAPK（Thr183/Tyr185）、p38MAPK、p-p38MAPK（Thr180/Tyr182）、ERK1/2、p-ERK1/2的影响。[结果]GLA可以显著抑制LPS诱导的RAW264.7细胞中iNOS和COX-2的蛋白表达（P〈0.05）,且在0～50μmol/LGLA浓度范围内存在剂量依赖关系。GLA可以显著抑制IκBα的降解（P〈0.05）,从而抑制NF-κB的激活。GLA可以显著抑制LPS诱导的JNK1/2以及ERK1/2的磷酸化（P〈0.05）,对p38的磷酸化没有显著的影响。[结论]GLA具有很好的消炎功效。抑制JNK1/2以及ERK1/2的磷酸化、抑制NF-κB的激活可能是其发挥生物学效应的重要机制。     

Effect of the gene silencing of phosphorus transporters on phosphorus absorption across primary cultured duodenal epithelial cell monolayers of chick embryos

The aim of the study was to investigate whether phosphorus (P) transporters, type IIb sodium-dependent phosphate cotransporter (NaP-IIb) and inorganic phosphate transporter 2 (PiT2), were directly involved in P absorption across primary cultured duodenal epithelial cell monolayers of chick embryos. The siRNAs against NaP-IIb or PiT2 were designed, synthesized and transfected into primary cultured duodenal epithelial cells of chick embryos. Then, the inhibitory efficiency of siRNAs against NaP-IIb or PiT2 was analyzed, and the most efficacious siRNAs were selected to be used for subsequent P absorption experiments. Briefly, primary cultured duodenal epithelial cells of chick embryos were transfected with either NaP-IIb or PiT2 siRNAs and grown in confluent monolayers on transwell plates. The untransfected or transfected cell monolayers were then incubated in an uptake medium containing 0 or 0.25 mmol L^–1 of P as KH₂PO₄ to measure the P absorption across duodenal epithelial cell monolayers. The results showed that among the siRNAs designed, si-1372 and si-890 were demonstrated to be the most effective in inhibiting the NaP-IIb and PiT2 expressions, respectively. Supplemental P increased (P=0.065) the protein abundance of PiT2 and enhanced (P<0.0001) P absorption in primary cultured duodenal epithelial cell of chick embryos. Furthermore, NaP-IIb silencing decreased (P=0.07) P absorption across duodenal epithelial cell monolayers, while PiT2 silencing had no effect (P=0.345). It is concluded that the NaP-IIb, but not PiT2, might be directly involved in the P absorption of chick duodenal epithelial cells.