Effects of Seal Oil and Tuna-Fish Oil on Platelet Parameters and Plasma Lipid Levels in Healthy Subjects

Fish are a rich source of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), two long-chain polyunsaturated n-3 fatty acids (LC n-3 PUFA) with cardiovascular benefits. A related but less-investigated LC n-3 PUFA, docosapentaenoic acid (DPA), is more common in seal oil and pasture-fed red meats. This study compared indicators of platelet function and plasma lipids in healthy volunteers given supplements containing these different fatty acids (FA) for 14 days. Subjects, randomised into three groups of ten, consumed capsules of tuna oil (210 mg EPA, 30 mg DPA, 810 mg DHA), seal oil (340 mg EPA, 230 mg DPA, 450 mg DHA) or placebo (sunola) oil. Supplementary LC n-3 PUFA levels were approximately 1 g/day in both fish and seal oil groups. Baseline dietary FA and other nutrient intakes were similar in all groups. Both fish and seal oil elevated platelet DHA levels (P < 0.01). Seal oil also raised platelet DPA and EPA levels (P < 0.01), and decreased p-selectin (P = 0.01), a platelet activation marker negatively associated with DPA (P = 0.03) and EPA (P < 0.01) but not DHA. Plasma triacylglycerol decreased (P = 0.03) and HDL-cholesterol levels increased (P = 0.01) with seal oil only. Hence, seal oil may be more efficient than fish oil at promoting healthy plasma lipid profiles and lowering thrombotic risk, possibly due to its high DPA as well as EPA content.     

Levels of Lipid Peroxidation in Human Plasma and Erythrocytes: Comparison between Fatty Acids and Cholesterol

Lipid peroxidation has gained renewed attention with increasing evidence showing its biological role in producing toxic compounds and cellular signaling mediators. The assessment of lipid peroxidation levels in vivo is difficult partly because lipids are oxidized by different oxidants by different mechanisms to give versatile types of products, which may undergo metabolism and secondary reactions. In the present study, total hydroxyoctadecadienoic acids (tHODE) and 7α- and 7β-hydroxycholesterol (t7-OHCh) from 44 healthy human subjects were assessed as biomarkers after reduction with sodium borohydride followed by saponification with potassium hydroxide comparing with the prevailing standard 8-isoprostaglandin F_2α (t8-iso-PGF_2α). The average concentrations of tHODE, total 8-isoprostaglandin F_2α (t8-iso-PGF_2α), t7α-OHCh, and t7β-OHCh were 203, 0.727, 87.1, and 156 nmol/l plasma and 1,917, 12.8, 1,372, and 3,854 nmol/l packed erythrocytes, respectively. The ratios of tHODE and t7-OHCh to the parent substrates were 194 and 3,519 μmol tHODE/mol linoleates and 40.9 and 686 μmol t7-OHCh/mol cholesterol in plasma and erythrocytes, respectively. It was found that (1) t7-OHCh in blood was unexpectedly high, as high as or even higher than tHODE, (2) the amounts of tHODE was more than 100 fold higher than t8-iso-PGF_2α (3) the level of lipid oxidation products in erythrocytes was higher than that in plasma, and (4) lipid peroxidation products level tended to increase while antioxidant level decrease with age. These products may be used as potential biomarker for assessment of lipid peroxidation and oxidative stress in vivo.     

Effect of Brazilin on Plasma Lipid Levels in Spontaneously Hypertensive Rats

The levels of plasma lipid and lipoprotein in spontaneous hypertensive male rats (SHR) fed on normal chow diet, SHR fed on normal chow diet containing 2% cholesterol plus 10% olive oil and SHR fed on the same fat rich diet with the administration (100 mg/kg, orally) of brazilin, 7,11b-Dihydrobenz [b] indeno 1,2-d) pyran-3,6a,9,10 [6H]-tetrol, were determined to elucidate the effects of brazilin on the improvement of abnormalities in plasma lipid and lipoprotein concentrations of essential hypertensive rats. Plasma levels of total cholesterol, triglyceride and high density lipoprotein-cholesterol of SHR were significantly changed toward normal physiological values by the treatment with brazilin.     

高压润滑油密封的端面设计对性能的影响

润滑油类密封的设计一直要求很高,由于其良好的润滑性和流动性,在石化企业的设备中应用较为广泛,所以带压的双密封的设计中一般都使用润滑油作为隔离液。高压的润滑油密封是一个设计难题,通过对某厂的密封设计过程和结构的分析,认为可以通过调整密封参数和密封环形状,控制端面锥度和热转角,以达到较好的密封效果。     

油封唇口压力大小及分布的有限元分析

利用ANSYS建立了橡胶油封的2维轴对称模型,分析了过盈量、唇口接触宽度R,弹簧劲度以及后唇角β与油封唇口压力大小及分布的关系。分析结果验证了前人在油封设计及应用选型方面经验的正确性。该分析方法在油封设计及选型方面将起到一定的指导意义。这些分析为油封的构型优化奠定了基础。     

Determination of Blood NOTCH3 Extracellular Domain and Jagged-1 Levels in Healthy Subjects

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is the most common genetic disorder among those responsible for hereditary strokes, and it is caused by a mutation in the NOTCH3 gene on chromosome 19. Blood biomarkers related to the Notch signaling pathway have not been investigated extensively in CADASIL. In this study, we measured the serum and plasma levels of NOTCH3 extracellular domain (N3ECD) and its ligand, Jagged-1, in 279 healthy subjects. The levels of N3ECD and Jagged-1 showed significant correlations in both serum (p < 0.0001, r = 0.2681) and plasma (p < 0.0001, r = 0.4065). The N3ECD levels were significantly higher in the serum than in plasma and tend to increase with age. In contrast, there was no significant difference between the serum and plasma levels of Jagged-1 levels. To summarize, we were able to measure N3ECD and Jagged-1 protein levels in healthy human serum and plasma. Taken together, our findings provide the basis for further studies investigating the clinical use of blood N3ECD and Jagged-1 levels for CADASIL and other Notch signaling-related diseases.     

憋压解封技术在注水井带压解封施工中的应用

随着油田开发进入中后期,油田注水已经成为油田稳产、增产的主要措施,注水井冲检施工越来越多,为了保证足够的地层能量,注水井带压作业已被各油田广泛认可并推广,注水井带压作业解封时,因油管被堵塞器堵死,造成带压解封困难。     

Several Lipid-Related Gene Polymorphisms Interact with Overweight/Obesity to Modulate Blood Pressure Levels

Little is known about the interactions of single nucleotide polymorphisms (SNPs) and overweight/obesity on blood pressure levels. The present study was undertaken to detect 10 lipid-related gene SNPs and their interactions with overweight/obesity on blood pressure levels. Genotyping of ATP-binding cassette transporter A1 (ABCA-1) V825I, acyl-CoA:cholesterol acyltransferase-1 (ACAT-1) rs1044925, low density lipoprotein receptor (LDL-R) AvaII hepatic lipase gene (LIPC) −250G > A, endothelial lipase gene (LIPG) 584C > T, methylenetetrahydrofolate reductase (MTHFR) 677C > T, the E3 ubiquitin ligase myosin regulatory light chain-interacting protein (MYLIP) rs3757354, proprotein convertase subtilisin-like kexin type 9 (PCSK9) E670G, peroxisome proliferator-activated receptor delta (PPARD) +294T > C, and Scavenger receptor class B type 1 (SCARB1) rs5888 was performed in 978 normal weight and 751 overweight/obese subjects. The interactions were detected by factorial regression analysis. The genotypes of ACAT-1 AC, LIPC GA and AA, and SCARB1 TT; LDL-R A-A- and LIPC GA; and SCARB1 TT were interacted with overweight/obesity to increase systolic, diastolic blood pressure (SBP, DBP) and pulse pressure (PP) levels; respectively. The genotypes of ACAT-1 CC; ACAT-1 AA and CC were interacted with overweight/obesity to decrease SBP, PP levels (p < 0.01–0.001); respectively. The differences in blood pressure levels between normal weight and overweight/obese subjects might partly result from different interactions of several SNPs and overweight/obesity.     

Influence of Oil Load and Maltodextrin Concentration on Properties of Tuna Oil Microcapsules Encapsulated in Two-Layer Membrane

The two layers of tuna oil-in-water emulsions containing different oil loads (5–10 wt%) and maltodextrin concentrations (10–20 wt%) were stabilized by a lecithin–chitosan membrane. The liquid emulsions were then spray dried at an inlet air temperature of 180 ± 2°C and an outlet air temperature of 85 ± 5°C. The characteristics of liquid emulsion (creaming and mean droplet size) and spray-dried microcapsules (moisture content, water activity, color, morphology, glass transition temperature, and encapsulation efficiency) were measured. The results suggest that two-layer oil-in-water emulsions are an effective system to produce high oil-loaded microcapsules, which may lead to its wide application for use in food products.     

ZLH型减速机油封的改进

减速机漏油现象普遍存在,文章介绍了对减速机轴封盖进行双重密封形式的改进方法及效果。     

Effects of Virgin Olive Oil on Blood Pressure and Renal Aminopeptidase Activities in Male Wistar Rats

High saturated fat diets have been associated with the development of obesity and hypertension, along with other pathologies related to the metabolic syndrome. In contrast, the Mediterranean diet, characterized by its high content of monounsaturated fatty acids, has been proposed as a dietary factor capable of positively regulating cardiovascular function. These effects have been linked to changes in the local renal renin angiotensin system (RAS) and the activity of the sympathetic nervous system. The main goal of this study was to analyze the role of two dietary fat sources on aminopeptidases activities involved in local kidney RAS. Male Wistar rats (six months old) were fed during 24 weeks with three different diets: the standard diet (S), the standard diet supplemented with virgin olive oil (20%) (VOO), or the standard diet enriched with butter (20%) plus cholesterol (0.1%) (Bch). Kidney samples were separated in medulla and cortex for aminopeptidase activities (AP) assay. Urine samples were collected for routine analysis by chemical tests. Aminopeptidase activities were determined by fluorometric methods in soluble (sol) and membrane-bound (mb) fractions of renal tissue, using arylamide derivatives as substrates. After the experimental period, the systolic blood pressure (SBP) values were similar in standard and VOO animals, and significantly lower than in the Bch group. At the same time, a significant increase in GluAP and IRAP activities were found in renal medulla of Bch animals. However, in VOO group the increase of GluAP activity in renal medulla was lower, while AspAP activity decreased in the renal cortex. Furthermore, the VOO diet also affected other aminopeptidase activities, such as TyrAP and pGluAP, related to the regulation of the sympathetic nervous system and the metabolic rate. These results support the beneficial effect of VOO in the regulation of SBP through changes in local AP activities of the kidney.     

A Comparison of the Levels of Lutein and Zeaxanthin in Corn Germ Oil,Corn Fiber Oil and Corn Kernel Oil

All commercial corn oil is obtained by pressing corn germ and/or extracting the germ with hexane. In the current study, six types of corn oil were prepared by extracting corn germ, corn fiber and ground corn, each with hexane or with ethanol. The levels of lutein, zeaxanthin and other carotenoids were quantitatively analyzed in the six corn oils. The levels of lutein + zeaxanthin in the oil ranged from 2.3 μg/g for hexane-extracted corn germ oil to 220.9 μg/g for ethanol-extracted ground corn oil. These results indicate that a diet that includes 30 g (~2 tbsp) per day of the unrefined corn oil obtained by extracting ground corn with ethanol would provide ~6 mg of lutein + zeaxanthin, the daily dosage that is currently considered to be necessary to slow the progression of age-related macular degeneration. Mention of trade names or commercial products in this publication is solely for the purpose of providing specific information and does not imply recommendation or endorsement by the U.S. Department of Agriculture.     

油品储运厂1号残压往复机填料密封改进

油品储运厂1号残压往复机填料密封故障频繁。文章对压缩机填料环结构进行分析,找出了故障原因。通过对填料密封环进行重新选型,对调整环进行改进,解决了问题。     

波纹管密封和多弹簧密封在炼油厂的应用与改进

波纹管密封和多弹簧密封因其密封性能可靠、安装操作简单,在石油化工行业中得到广泛应用.在应用过程中,也发现了该密封存在的一些问题.通过对冷却系统的改进、检测工具的研制和规范安装程序,大大提高了这类机械密封的使用寿命.     

液压胀接接头的密封压力

根据液压胀接变形曲线及其胀接接头密封机理 ,分析槽边缘的接触正压力 ,进一步确定开槽管板胀接接头密封压力及其与胀接压力和开槽宽度之间的关系     

高压法兰密封泄漏处理

概述了高压法兰透镜垫密封的结构和运行情况。针对泄漏产生的原因、从振动、装配、工艺操作及管件材质等不同角度介绍了减少泄漏的措施。根据密封元件的损坏情况，提出了检修密封元件、改造透镜垫等消除泄漏的方法。     

加压转鼓过滤机的密封及转鼓分析

提出一种加压转鼓过滤机的设计方案。介绍其结构、工作原理、应用领域及特点;对内外转鼓间的填料密封进行理论分析;利用通用有限元软件对复杂载荷联合作用下的外转鼓进行强度和密封分析。有限元数值模拟的结果表明,外转鼓的设计方案满足设计要求,在没有成熟设计理论的背景下,为设计方案的可靠性提供了依据。     

压缩机油封失效分析与对策

机械油封的工作条件与环境是复杂多变的,因而它的失效形式也是诸多因素交互影响所致,文章介绍了油封的结构及密封原理,分析了氢气压缩机油封的失效原因,并针对氢气压缩机油封失效提出了解决措施,在装置检修期间对新氢机油封进行了更换,解决了氢气压缩机油封泄漏问题。     

浅谈汽车发动机油封的现状与发展

对我国汽车发动机油封生产的现状,从原材料、工艺、设备等方面进行了简单分析,指出国内外的差距,并对今后的发展提出几点粗浅的建议。