CB·氨基酸在猪卵母细胞孤雌激活及体外培养中的作用

[目的]研究CB、氨基酸在猪卵母细胞孤雌激活及体外培养体系中的作用,为优化相关技术体系提供依据。[方法]卵母细胞经体外成熟培养,采用不同孤雌激活方法(Ele.+CB组、CB组、Ele.组、对照组),研究CB在激活中的作用。激活后采用PZM3培养液,并去除氨基酸成分,探索氨基酸对体外培养胚胎的作用。[结果]CB+Ele.组的卵裂率显著地高于其他3组(P<0.05),囊胚率为32.7%,囊胚细胞数为61.4,而其他3组均未出现囊胚。电激活(脉冲电压100 V/mm,脉冲时程100μs,脉冲次数1次)联合CB处理,可激活卵母细胞体外发育至囊胚,CB有助于提高卵裂率、囊胚率。添加氨基酸的培养液中的卵母细胞的卵裂率、囊胚率、囊胚细胞数显著提高(P<0.05),表明氨基酸能提高猪孤雌激活胚胎培养效果。[结论]添加CB、氨基酸在猪卵母细胞孤雌激活及体外培养体系中能提高胚胎的培养效果。     

简易气调贮藏对冬枣果实乙醇、有机酸含量及相关酶活性的影响

该文研究了简易气调贮藏(0℃)对冬枣贮藏期间乙醇、有机酸含量及相关酶活性变化的影响,探讨了冬枣乙醇发酵机制。结果表明：随着贮期的延长,对照积累了较高的乙醇和乙醛含量,丙酮酸脱羧酶(PDC)和乙醇脱氢酶(ADH)的活性提高,有机酸水平降低;而简易气调贮藏延缓了乙醇和乙醛含量的增加,降低了PDC和ADH的活性,并保持了较高的有机酸含量。有机酸中柠檬酸、t-顺乌头酸、琥珀酸和延胡索酸含量随着贮期的延长逐渐下降,苹果酸前期下降,后略有增加;而丙酮酸含量前期增加峰值出现后下降,推测丙酮酸的增加与进入三羧酸循环的有机酸流量的降低是导致冬枣果实乙醇发酵的机制之一。     

NdCl3对水分亏缺下小麦种子荫发与幼苗抗旱性的影响

研究结果表明,当培养液含35μmol/LNdCl₃时,小麦种子在0%～30%PEG中萌发率与萌发势均明显提高.控制土壤含水量为18%、12%、8%的盆栽试验亦证明700μmol/LNdCl₃浸种可促进小麦的出苗率和出苗速度.以350、700;μmol/LNdCl₃浸种的麦苗,在停止浇水进行干旱处理后叶片RWC、叶绿素含量均高于对照,而3500μmol/LNdCl₃浸种,上述指标则低于对照,虽然350～3500μmol/LNdCl₃浸种都降低了质膜电解质外渗,尤以700μmol/L为最,但均不改变膜极性脂肪酸的配比.     

黑龙江林蛙输卵管营养成份分析

本实验用日立８３５—５０氨基酸分析仪、岛津ＧＣ—９Ａ气相色谱仪、索氏脂肪提取器分别测定了黑龙江林蛙输卵管阴干制品中氨基酸、脂肪酸、脂肪的含量。测得氨基酸总和为５０．７９％（伊春）、４７．４８％（大兴安岭）；脂肪酸总和为２．４４６９ｍｇ／ｇ（伊春）、２．７９３１ｍｇ／ｇ（大兴安岭）；脂肪为３．４６％（伊春）、３．１１％（大兴安岭）。结果表明，黑龙江林蛙输卵管是一种高蛋白、低脂肪的滋补品且具有较高的药用价值。     

Fatty acid status in captive and free-ranging black rhinoceroses (Diceros bicornis)

The fatty acid (FA) patterns of plasma/serum triglycerides (TG), phospholipids (PL) and cholesteryl esters (CE) of captive and free-ranging black rhinoceroses (Diceros bicornis) were investigated. Free-ranging animals (n = 28) stemmed from four different regions. Captive animals sampled included specimens from North American (n = 11) and three different European facilities (n = 6). The European animals were tested on 1-4 different diets, resulting in a total of 15 blood samples. Regardless of differences between the free-ranging animals from different regions, differences between captive and free-ranging animals were relatively uniform: captive animals had higher overall proportions of polyunsaturated fatty acid (PUFA), due to levels of linoleic acid (LA, 18:2n6) that were drastically increased as compared to free-ranging animals. In contrast, levels of alpha-linolenic acid (ALA, 18:3n3) were consistently lower on conventional zoo diets. n6/n3 ratios for TG, PL and CE were 1.6, 10 and 8 in samples from free-ranging animals, respectively, as compared to 4.1-16.3, 16-148 and 40-277 in samples from captive animals. There was a distinct correlation between the proportion of grain-based products (commercial concentrates, plain grains and bread) in the diets of the European animals and the measured levels of n6 PUFA. An animal from a facility with a very low proportion of grain products in the diet nevertheless had high LA readings, most probably due to the use of sunflower oil as 2% (dry matter basis) of its diet. One animal that received a high proportion of grass meal pellets due to an oral disease had increased ALA contents after the diet change. These results allow conclusions on the suitability of diets fed in captivity: the black rhinoceros is prone to several uncommon diseases that have been suspected to be linked to oxidative damage, possibly due to the disposition of this species to excessive iron storage. An unnatural dietary loading with PUFAs would exacerbate this problem. Additionally, n6 FAs are known as precursors of pro-inflammatory mediators, and their overrepresentation could therefore exacerbate any inflammatory processes. Therefore, the current practice of using grain-based feeds as major ingredients in captive rhinoceros diets is discouraged. Diet items containing ALA (a precursor of anti-inflammatory mediators) such as, fresh grass, fresh browse, the respective silages should be included at higher levels in diets for captive black rhinoceroses. Grass meal pellets, although a good source of ALA and linked with high levels of ALA in an animal of this study, must be chosen with care for black rhinoceroses due to their particular proneness for high iron contents.     

短链脂肪酸介导的肠上皮和抗炎调节研究进展

哺乳动物体中的肠道菌群是细菌生态系统的组成部分,从动物出生时起,这些微生物就对免疫系统的发育、功能和调节起着非常重要的作用。当前,越来越多的研究集中在微生物对宿主细胞代谢的影响上。短链脂肪酸(SCFA)作为肠道菌群的一种代谢产物,对肠道稳态的维持具有重要作用。SCFA是肠道上皮细胞的重要燃料,能增强肠屏障功能。作为信号分子,SCFA可以通过细胞表面G蛋白偶联受体(GPCR)发出信号,从而激活控制免疫功能的信号级联反应;还可以通过底物转运蛋白进入细胞,抑制组蛋白脱乙酰化酶(HDAC),最终达到降低肠道炎症反应。本文综述了微生物SCFA的产生及其对肠道黏膜的影响,并通过激活细胞表面GPCR以及抑制组蛋白去乙酰化酶(HDACs)来调节免疫反应的作用。     

Responses of Soil Enzyme Activities and Microbial Community Composition to Moisture Regimes in Paddy Soils Under Long-Term Fertilization Practices

The effects of fertilization on activity and composition of soil microbial community depend on nutrient and water availability;however,the combination of these factors on the response of microorganisms was seldom studied.This study investigated the responses of soil microbial community and enzyme activities to changes in moisture along a gradient of soil fertility formed within a long-term(24 years)field experiment.Soils(0–20 cm)were sampled from the plots under four fertilizer treatments:i)unfertilized control(CK),ii)organic manure(M),iii)nitrogen,phosphorus,and potassium fertilizers(NPK),and iv)NPK plus M(NPK+M).The soils were incubated at three moisture levels:constant submergence,five submerging-draining cycles(S-D cycles),and constant moisture content at 40%water-holding capacity(low moisture).Compared with CK,fertilization increased soil organic carbon(SOC) by 30.1%–36.3%,total N by 27.3%–38.4%,available N by 35.9%–56.4%,available P by 61.4%–440.9%,and total P by 28.6%–102.9%.Soil fertility buffered the negative effects of moisture on enzyme activities and microbial community composition.Enzyme activities decreased in response to submergence and S-D cycles versus low moisture.Compared with low moisture,S-D cycles increased total phospholipid fatty acids(PLFAs)and actinomycete,fungal,and bacterial PLFAs.The increased level of PLFAs in the unfertilized soil after five S-D cycles was greater than that in the fertilized soil.Variations in soil microbial properties responding to moisture separated CK from the long-term fertilization treatments.The coefficients of variation of microbial properties were negatively correlated with SOC,total P,and available N.Soils with higher fertility maintained the original microbial properties more stable in response to changes in moisture compared to low-fertility soil.     

Relation between Habitual Diet and Canine Mammary Tumors in a Case-Control Study

In the present case-control study several dietary and nutritional factors were investigated to determine if a relationship exists between diet and development of mammary tumors in female dogs. Control female dogs (n = 86) were compared with a case group of dogs (n = 102) with dysplasias or tumors of the mammary gland. A questionnaire providing information on the dog's body conformation and dietary and reproductive histories was answered by the owners. Serum selenium and retinol concentrations and the fatty acid profile in subcutaneous adipose tissue were analyzed as indicators of nutritional status. Obesity at 1 year of age and 1 year before the diagnosis of mammary nodules was found to be significantly related to a higher prevalence of mammary tumors and dysplasias. The intake of homemade meals (compared to that of commercial foods) was also significantly related to a higher incidence of tumors and dysplasias. Other significant risk factors were a high intake of red meat, especially beef and pork, and a low intake of chicken. The subcutaneous fatty acid profile and the serum selenium concentration were not significantly different in the cases and the controls, with the exception of C18:1 fatty acid (oleic acid) content, which was significantly higher in the cases than in healthy controls. Serum retinol concentration was significantly lower in the cases than in the controls. In the multivariate analysis, older age, obesity at 1 year of age, and a high red meat intake were independently and significantly associated with the risk of developing mammary tumor and dysplasias.     

不同发育时期澳洲坚果果皮抗氧化物质成分分析

以云南省永德县大雪山乡澳洲坚果种植基地广泛种植的优良品种O.C.为研究材料,利用超高效液相色谱-串联质谱（UPLC-MS/MS）的技术方法,对该品种花后30天、60天和90天的果皮进行代谢组学分析,探究不同发育时期澳洲坚果果皮酚酸类物质组分及含量的变化,为果皮中酚酸类抗氧化物质的开发和利用提供参考依据。结果表明：不同发育时期果皮中的酚酸类物质组分及含量有较大差异,在检测到的114个代谢物中,绿原酸 (3-O-咖啡酰奎宁酸)、1-O-阿魏酰-D-葡萄糖和1-O-对香豆酰-β-D-葡萄糖等物质的含量在花后30天最高,表明发育前期需要大量能量物质作为生长代谢原料;熊果苷、6''-咖啡酰熊果苷、红景天苷、龙胆酸、阿魏酸、3,4-二没食子酰莽草酸、没食子苯乙酮、原儿茶酸、水杨酸以及豆腐果苷等多种物质在花后60天及90天含量较高;6''-对香豆酰熊果苷和3,4-二甲氧基肉桂酸为花后90天标志性物质。结论： 本文分析测试了澳洲坚果果实不同发育期果皮中酚酸类物质的种类及含量变化,发现果皮中含有美白、抗菌等活性成分,具有一定的药用价值,为今后澳洲坚果早期落果及采后果皮加工利用、保健品及药物开发等奠定了很好的基础。