Validation of human recombinant tissue factor-activated thromboelastography on citrated whole blood from clinically healthy dogs

BACKGROUND: Thromboelastography (TEG) is an analytical method that enables global assessment of hemostatic function in whole blood (WB) with evaluation of both plasma and cellular components of hemostasis. TEG has a largely unused potential in the diagnostic workup and monitoring of dogs with hemostatic disorders and it may be a valuable supplement to traditional coagulation parameters. OBJECTIVES: The objective of this study was to establish a clinically applicable reference interval for a TEG assay using recombinant human tissue factor (TF) as the activator on citrated WB from clinically healthy dogs and to evaluate the stability of citrated WB stored for 30 minutes (T30) and 120 minutes (T120) at room temperature (RT). Additionally, we evaluated the analytical variation in reaction time (R), clotting time (K), angle (alpha), and maximum amplitude (MA). METHODS: Blood was collected from 18 clinically healthy dogs. Duplicate TEG analyses with TF as the activator at a concentration of 1:50,000 were performed on canine citrated WB at T30 and T120. R, K, a, and MAwere analyzed. RESULTS: Mean TEG values at T30/T120 were R = 5.61/4.91 minutes, K = 4.20/3.34 minutes, alpha = 45.33/50.90 degrees , and MA = 47.96/50.19 mm. Significant differences in these values were observed after storage for T30 and T120 at RT, with a tendency towards hypercoagulability at T120. The mean coefficients of variation were low. CONCLUSIONS: Canine citrated WB can be used for TEG analysis with human recombinant TF as the activator when stored at RT for T30 or T120. At both time points, the analytical variation was low, suggesting that TEG analysis may be of value in evaluating dogs with hemostatic disorders. A fixed time point should be chosen for serial measurements.     

铝离子胁迫下大豆根尖柠檬酸的分泌及SGA1基因的表达

为揭示铝离子诱导大豆根尖分泌有机酸的特点及介导有机酸分泌的信号途径,采用溶液培养试验方法调查Al Cl3对大豆品种(广州本地2号)根尖有机酸分泌及SGA1基因表达的影响。结果表明,Al Cl3胁迫下大豆活体根尖分泌柠檬酸,且分泌量随着铝浓度(25、50μmol L–1Al Cl3)和处理时间(2~12 h)的增加而增加;大豆根尖以模式II分泌柠檬酸,处理后的前4 h,分泌速率很低,其后显著提升;有机酸明显分泌的诱导期长达6 h;在50μmol L–1 Al Cl3的溶液中添加异三聚体G蛋白抑制剂百日咳毒素(200 ng m L–1),柠檬酸分泌减少38.7%。RT-PCR分析结果显示,Al Cl3溶液诱导大豆根尖SGA1基因的表达,其表达水平随着铝处理时间(0.5~12.0 h)的延长有提升的趋势,而诱导的SGA1基因表达明显早于有机酸开始分泌时间(6 h)。这些结果表明,铝离子诱导大豆根尖分泌柠檬酸及SGA1基因的表达,异三聚体G蛋白可能作为铝胁迫信号开关器参与有机酸分泌的调控。     

温室甜瓜果实糖酸积累模拟模型研究

通过不同类型温室春、秋茬甜瓜栽培,基于有效积温、日温差积与甜瓜果实蔗糖、柠檬酸间关系的回归分析,建立了甜瓜果实蔗糖、柠檬酸及糖酸比及有效积温与日温差积的模拟模型.结果表明,甜瓜果实蔗糖、柠檬酸及糖酸比均随有效积温与日温差累积的增加呈logistic曲线函数变化,但不同栽培茬口函数模型的常数项有差异,它与日温差累积呈线性关系.验证试验结果表明:该模型能较好地模拟甜瓜果实蔗糖、柠檬酸积累过程与糖酸比变化,可精确预测甜瓜果实的成熟特性,因而在确定甜瓜优质采收期中具有很好的应用价值.     

铝胁迫下大豆根系有机酸积累的特性

为探讨铝胁迫对大豆根系有机酸累积的影响,以大豆品种粤春03-3为研究对象,通过水培方法进行不同时间的铝处理,分别测定大豆根系的相对生长率、以及距根尖0~2和2~4 cm根段的铝含量、苹果酸浓度、柠檬酸浓度和草酸浓度等。结果表明:铝处理明显抑制了大豆根系的生长。随着铝处理时间的延长,0~2 cm根段的铝含量明显降低,而2~4 cm根段的铝含量明显增加。另外,铝胁迫对不同根段的有机酸累积的影响也不同。铝处理6 h显著提高了大豆根系的苹果酸浓度,但对柠檬酸和草酸浓度均无明显影响。铝处理12 h后,0~2 cm根段中3种有机酸的浓度在铝处理和对照之间均无明显差异,但2~4 cm根段的苹果酸浓度和草酸浓度均明显高于对照。说明苹果酸和草酸在大豆根系铝毒的内部忍耐机制中起着重要作用。     

中兽药乌梅颗粒质量标准的研究

为了建立乌梅颗粒的质量标准,采用薄层色谱法(TLC)对乌梅、黄连进行鉴别;用高效液相色谱法测定乌梅颗粒中枸橼酸的含量。色谱条件为Silgreen C18(4.6 mm×250 mm,5μm)色谱柱;流动相为乙腈-0.5%磷酸二氢铵溶液(3∶97)(用磷酸调节p H值至3.0);检测波长为210 nm;流速为0.6 m L/min;柱温为室温。研究建立了乌梅、黄连的薄层色谱定性鉴别的方法;建立了HPLC测定乌梅颗粒中枸橼酸含量的方法。建立的乌梅颗粒鉴别及枸橼酸含量测定方法简单、易于操作、准确度高、重现性好,可用于乌梅颗粒的质量控制。     

Effects of Common Anticoagulants on Routine Plasma Biochemistry of Horse and Comparison with Serum

The effects of various types of anticoagulants on plasma biochemistry have been studied in humans and various animals; however, limited information exists for effects on horse plasma biochemistry. Ten clinically healthy Thoroughbred horses were blood sampled in tubes containing different anticoagulants as well as no anticoagulant. The concentrations of glucose, cholesterol, triglyceride, total bilirubin, blood urea nitrogen (BUN), creatinine, total protein, albumin, calcium, inorganic phosphorus, magnesium and iron, and the activity of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), creatine kinase (CK), and gamma glutamyl transferase (GGT) were measured. Except for the amounts of inorganic phosphorus, magnesium, and GGT, other measured parameters were significantly lower in citrated plasma than in serum. When corrected for dilution, significant differences were seen for the amounts of glucose, cholesterol, triglyceride, bilirubin, calcium, iron, and the activity of ALT, ALP, and CK in citrated plasma. Most parameters did not show any difference; however, significant decreases in BUN, total bilirubin, ALT, and CK activity were seen when heparin was used as an anticoagulant. When compared with serum, using ethylenediaminetetra-acetic acid (EDTA) as an anticoagulant produced a significant difference in the amounts of measured plasma parameters with the exception of GGT, albumin, creatinine, inorganic phosphorus, and triglyceride.     

Chemical forms of iron in xylem sap from graminaceous and non-graminaceous plants

Graminaceous plants can take up iron-phytosiderophore complexes, whereas non-graminaceous plants absorb ferrous ions after the reduction of ferric compounds at the root cell membranes. The iron (Fe) in the roots may be transported to the aerial plant parts through the xylem. We compared the chemical forms in xylem sap collected from the cut stems of three graminaceous plants (rice [Oryza sativa L.], maize [Zea mays L.], barley [Hordenum vulgare L.]) and three non-graminaceous plants (tomato [Lycopersicon esculentum Mill.], soybean [Glycine max Merr.], castor bean [Ricinus communis L.]) grown in composite soils for the concentrations of iron and iron-chelating compounds (nicotianamine, phytosiderophores, citrate). We also fractionated the xylem saps by size-exclusion chromatography to gain insight into the chemical forms of iron. The Fe concentrations in the xylem sap ranged from 9 to 40 μM. Nicotianamine was found in the xylem sap from all the plants examined, with higher concentrations in the non-graminaceous plants. In contrast, phytosiderophores (2’-deoxymugineic acid and mugineic acid) were predominantly detected in the graminaceous plants. The concentrations of free citrate varied greatly (from 4 to 2200 μM) among the six plant species. The xylem sap iron in non-graminaceous plants may form two types of Fe-citrate, whereas in graminaceous plants, the bound Fe forms may be largely two types of Fe-citrate with various Fe-phytosiderophores.     

控释掺混肥对花生生育期间剖面土壤铵态氮和硝态氮含量变化的影响

以普通单质肥料为原料,制备了N：P2O4：K2O比例分别为14：13：15,11：14：17和14：14：17的3种控释掺混肥料,于2007年在山东省泰安市徂徕镇进行田间试验,研究了不同配方控释掺混肥料品种对花生生育期间剖面土壤铵态氮和硝态氮含量动态变化的影响。结果表明,在花生不同生育期不同施肥处理剖面土壤中的铵态氮耕层含量最高,随剖面深度的增加呈现出先降低后升高再降低的变化趋势,硝态氮随剖面土壤深度的增加变化趋势与铵态氮相同,但含量升高的土层随生育期的延长不断加深。与常规肥料相比施用控释掺混肥料能够在结荚期和饱果成熟期提高剖面相同土层土壤中铵态氮的含量,降低硝态氮的含量,减少对地下水产生污染的风险。能克服常规肥料苗期养分过多造成烧苗和生长后期养分供应不足的缺点,不同配方的3种控释掺混肥的一次性施用显著优于一次性施用常规肥料。与普通肥料相比,不同品种控释掺混肥处理提高肥效降低污染风险的效益顺序为：控释掺混肥料1〉控释掺混肥料2〉控释掺混肥料3。     

滴灌施肥对石灰性土壤铁、磷有效性和番茄生长的影响

 研究了石灰性土壤中畦灌和滴灌方式对土壤pH和有效铁、磷含量的影响。结果表明，滴灌施肥可提高水、肥生产效率，增加番茄产量。滴灌条件下根围润湿区土壤可以经常保持较高的含水量，pH高于根外非润湿区和畦灌区，其土壤有效磷的含量高，而土壤有效铁的含量较低。在滴灌施肥条件下配用一定量柠檬酸不仅可降低润湿区土壤pH，还可提高土壤有效铁含量，并增加叶片中铁、磷的含量，进而果实产量也相应地提高。