尿素和氢氧化钙处理玉米秸对体外瘤胃内环境的影响

为了研究尿素和氢氧化钙处理玉米秸对体外瘤胃内环境的影响,采用2因素3水平完全交叉试验设计,将尿素和氢氧化钙均按玉米秸干物质质量的2%、3%和4%的量分别添加,共9个试验组和1个对照组(添加量为0),通过短期人工瘤胃技术研究不同水平尿素和氢氧化钙处理玉米秸对瘤胃液pH值、氨氮(NH3-N)质量浓度、微生物蛋白(MCP)产量和挥发性脂肪酸(VFA)浓度的影响。结果表明,不同水平尿素和氢氧化钙处理玉米秸对瘤胃液pH值影响不显著(P>0.05);对氨氮质量浓度影响显著或极显著(P<0.05或P<0.01),但均在正常范围内;在MCP产量方面,第6、7、8组和第10组极显著高于对照、第2、3、4组和第9组(P<0.01),分别比对照组高26.74%、27.91%、36.05%和32.56%,第7、8组和第10组3个组间无显著差异(P>0.05),第8组和第10组显著高于第5组和第6组(P<0.05),第7组和第5、6组间无显著差异(P>0.05);第10组的乙酸、丙酸和丁酸3种挥发性脂肪酸总浓度极显著高于对照组(P<0.01),比对照组高84.59%,第10组极显著或显著高于其他试验组(P<0.01或P<0.05)。结果显示,第10组即尿素和氢氧化钙处理玉米秸时,添加水平均为其干物质量的4%是最适宜的。     

Evaluation of the antioxidant capacity of individual phenolic compounds in virgin olive oil

Virgin olive oil has a high resistance to oxidative deterioration due to its tryacylglycerol composition low in polyunsaturated fatty acids and due to the presence of a group of phenolic antioxidants composed mainly of polyphenols and tocopherols. We isolated several phenolic compounds of extra virgin olive oil (phenyl-ethyl alcohols, lignans, and secoiridoids) by semipreparative high-performance liquid chromatography (HPLC) and identified them using ultraviolet, atmospheric pressure chemical ionization, and electrospray ionization MS detection. The purity of these extracts was confirmed by analytical HPLC using two different gradients. Finally, the antioxidant capacity of the isolated compounds was evaluated by measuring the radical scavenging effect on 1,1-diphenyl-2-picrylhydrazyl radical, by accelerated oxidation in a lipid model system (OSI, oxidative stability instrument), and by an electrochemical method.     

Two G protein oncogenes in human endocrine tumors

Somatic mutations in a subset of growth hormone (GH)-secreting pituitary tumors convert the gene for the alpha polypeptide chain (alpha s) of Gs into a putative oncogene, termed gsp. These mutations, which activate alpha s by inhibiting its guanosine triphosphatase (GTPase) activity, are found in codons for either of two amino acids, each of which is completely conserved in all known G protein alpha chains. The likelihood that similar mutations would activate other G proteins prompted a survey of human tumors for mutations that replace either of these two amino acids in other G protein alpha chain genes. The first gene so far tested, which encodes the alpha chain of Gi2, showed mutations that replaced arginine-179 with either cysteine or histidine in 3 of 11 tumors of the adrenal cortex and 3 of 10 endocrine tumors of the ovary. The mutant alpha i2 gene is a putative oncogene, referred to as gip2. In addition, gsp mutations were found in 18 of 42 GH-secreting pituitary tumors and in an autonomously functioning thyroid adenoma. These findings suggest that human tumors may harbor oncogenic mutations in various G protein alpha chain genes.     

杜仲提取物对三黄鸡生产性能和胴体品质的影响

为探明杜仲提取物在肉鸡日粮中的适宜添加量,选用1日龄健康三黄鸡150只,随机分为5组,每组3个重复,分别饲喂5种不同日粮,第5组为空白对照组,第1,2,3,4组为试验组,在基础日粮中分别添加1500,2000,2500g／t的杜仲提取物或50mg／kg的黄霉素（效价为8％）．试验分两个阶段饲养（0-4周龄和5～10周龄）．试鸡自由采食和饮水．结果表明,日粮中添加杜仲提取物能显著提高三黄鸡平均日增重,提高饲料转化率,改善三黄鸡胴体品质,且能明显提高胸肌率．建议在肉鸡日粮中添加2000-2500g／t的杜仲提取物．     

不同品种滴灌棉花水氮效应差异性比较

研究选取当地两个主栽棉花品种,通过不同水、氮用量研究棉花品种间在产量、氮肥吸收利用和水分利用效率的差异性。结果表明:标杂A1品种总体表现要优于新路早33号,干物质积累和籽棉产量上在低水条件下(3 600m3/hm2)品种间差异不显著,中、高水处理下(4 500m3/hm2,5 400m3/hm2)品种间差异均达到显著水平;两个施氮水平下(240kg/hm2,320kg/hm2)品种间总吸氮量和氮肥利用效率差异均显著;低水处理下两个施氮水平品种间水分利用效率差异不显著,中水处理下品种间水分利用效率差异显著,高水低氮处理水分利用效率在两个品种间差异不显著,但在高水高氮施用量条件下差异表现显著。     

Effects of different active constituents of Gynostemma pentaphyllum on mitochondrial energy metabolism-related proteins in endothelial cells induced by ox-LDL

AIM To investigate the effects of different components of Gynostemma pentaphyllum ［gypenosides (Gps), gypenoside XLIX (GpXLIX) and ginsenoside Rb3 (GRb3)］ on mitochondrial energy metabolism-related proteins in endothelial cells induced by oxidized low-density lipoprotein (ox-LDL). METHODS EA.hy926 cells were divided into control group, model group, Gps group, GpXLIX group and GRb3 group. The cells in control group were cultured only in DMEM complete medium. The cells in model group were treated with 100 mg/L ox-LDL for 48 h. The cells in Gps group, GpXLIX group and GRb3 group were treated with 100 mg/L ox-LDL for 24 h, and then treated with Gps, GpXLIX and GRb3 at 100 mg/L for another 24 h, respectively. The ATP content in each group was detected by ELISA. The expression levels of mitochondrial energy metabolism-related proteins, cytochrome C oxidase subunit 5a （Cox5a）, NADH:ubiquinone oxidoreductase core subunit S1 （Ndufs1）, ATP synthase F1 subunit alpha (ATP5a) and cytochrome C (Cyt C）, were determined by Wes automatic Western blot quantitative analysis system and Western blot. RESULTS Compared with control group, the ATP content in model group was decreased (P<0.01). After drug intervention, the ATP content increased to different degrees in Gps group, GpXLIX group and GRb3 group (P<0.01). The results of Wes automatic Western blot quantitative analysis system were consistent with those of Western blot. These results showed that compared with control group, the protein expression of Cox5a, Ndufs1 and ATP5a in model group was decreased, and the protein expression of Cyt C was increased (P<0.01). After intervention, the protein expression of Cox5a, Ndufs1 and ATP5a was increased and the protein expression of Cyt C was decreased in Gps group, GpXLIX group and GRb3 group (P<0.05 or P<0.01). Among them, the effect of Gps on the protein expression of Cox5a, Ndufs1 and Cyt C was significantly stronger than those of the 2 monomer components, and the effect of GRb3 was found to be superior in the 2 monomer components. The effect of GpXLIX on ATP5a protein was superior to the other 2 components. CONCLUSION Gynostemma total saponins and related active ingredients protect ox-LDL-induced endothelial cells by affecting mitochondrial energy metabolism-related proteins, thereby preventing and treating atherosclerosis.     

Increased frequency of phytosanitary pod removal in cacao (Theobroma cacao) increases yield economically in eastern Peru

Diseases caused by Moniliophthora roreri (moniliasis), Crinipellis perniciosa (witches’ broom) and Phytophthora palmivora (black pod) are the most important factors limiting cocoa production in Peru and cultural management is considered to be the only practical means of control for the smallholder. The objective of this study was to develop an epidemiologically and economically sound control recommendation based on the frequency of phytosanitary pod removal. Weekly removal of diseased pods reduced the incidence of diseases significantly in comparison with fortnightly removal. In three fields, moniliasis was decreased by 26–41%, black pod by 35–66% and witches’ broom on pods by 14–57%. The cumulative effect was a consistent yield increase from an average of 504–660 kg ha⁻¹ yr⁻¹. Returns compensated for increased labour costs. Weekly pod removal was 32% more profitable. Time-course analyses indicated that weekly removal should be practised throughout the year under field conditions of eastern Peru.     

Retrospective Study: Incidence of ionized hypocalcemia in septic dogs and its association with morbidity and mortality: 58 cases (2006–2007)

Objective – To determine the incidence rate and prognostic significance of ionized hypocalcemia (iHCa) among septic dogs. Design – Retrospective study Setting – Veterinary teaching hospital Animals – Fifty‐eight septic dogs that were presented to Cornell University Hospital for Animals between January 2006 and December 2007. Procedure – Cases were diagnosed with sepsis if they exhibited 2 or more criteria of the systemic inflammatory response syndrome with a concurrent documented infectious focus. Cases were excluded if diagnosed with a concurrent illness reportedly associated with calcium derangements. Lowest, mean, and highest blood ionized calcium concentrations were recorded and statistically analyzed for an association with morbidity, as measured by duration of hospitalization and number of blood product transfusions, and outcome. In addition, the incidence rate of iHCa was recorded. Results – Of the 58 cases included in this study, iHCa was documented in 4 of 6 (67%) patients that died, 5 of 19 (26%) euthanized patients and 5 of 33 (15%) patients that survived to discharge, with an overall incidence of 24%. Dogs that died during hospitalization had more severe iHCa than patients that were discharged or euthanized as well as significantly lower mean ionized calcium concentrations than patients who were discharged. Severity of iHCa was also associated with a longer duration of hospitalization. The highest ionized calcium concentration was not associated with outcome. Conclusion and Clinical Relevance – This study is the first to document the incidence of iHCa among septic dogs. Because both low mean ionized calcium and the lowest documented ionized calcium concentration are associated with poor outcome, it is likely that both the severity and duration of hypocalcemia are important in these patients. Further prospective studies investigating the prognostic significance, etiology and treatment of iHCa among septic veterinary patients are needed to better understand its role in sepsis.