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81.
The new American Dietary Guidelines now recommend optimizing the types of fat consumed instead of reducing or eliminating fat from the diet. Chicken eggs are a means to deliver essential and beneficial human dietary fatty acids (FA), and can be staple component of healthy eating behavior. Additionally, polyunsaturated fatty acids can be increased in the avian egg yolk by simply incorporating selected lipid sources into the avian diet. Poultry feed rich in omega‐3 FA (omega‐3) has allowed commercialization of enriched eggs containing up to 600 mg of omega‐3. Conjugated linoleic acid (CLA) has also been used in the research setting to enrich eggs to provide a portion of the 3–4 g CLA day?1 needed to promote weight loss to combat obesity. However, Americans consume only 50% of the omega‐3 recommended adequate intake, and average CLA consumption is under 600 mg day?1. While a variety of foods are naturally rich in omega‐3, conventional sources of CLA are limited to bovine milk and meat, which do not provide enough CLA to produce clinical effects in a balanced diet. Since eggs and egg‐based products are common in the Western diet, eggs enriched with both omega‐3 and CLA using dietary additions to poultry feed may promote consumption of the recommended levels of these FA. This article reviews the design of poultry eggs with enhanced lipid profiles through dietary intervention, and discusses the future direction of enriched egg research.  相似文献   
82.
The innate immune system of the skin is thought to depend largely on a multi-layered mechanical barrier supplemented by epidermis-derived antimicrobial peptides. To date, there are no reports of antimicrobial antibody secretion by the epidermis. In this study, we report the expression of functional immunoglobulin G (IgG) and immunoglobulin A (IgA), previously thought to be only produced by B cells, in normal human epidermal cells and the human keratinocyte line HaCaT. While B cells express a fully diverse Ig, epidermal cell-expressed IgG or IgA showed one or two conservative VHDJH rearrangements in each individual. These unique VDJ rearrangements in epidermal cells were found neither in the B cell-derived Ig VDJ databases published by others nor in our positive controls. IgG and IgA from epidermal cells of the same individual had different VDJ rearrangement patterns. IgG was found primarily in prickle cells, and IgA was mainly detected in basal cells. Both epidermal cell-derived IgG and IgA showed potential antibody activity by binding pathogens like Staphylococcus aureus, the most common pathogenic skin bacteria, but the microbial-binding profile was different. Our data indicates that normal human epidermal cells spontaneously express IgG and IgA, and we speculate that these Igs participate in skin innate immunity.  相似文献   
83.
Branched polyethyleneimine (bPEI) was used to modify the surface of Fe3O4 nanoparticles coated with silica layer, and then, it was treated with ethyl iodide to prepare Fe3O4@SiO2@Ethylated‐bPEI. In the next step, the yolk–shell structure was gained by selectively etching the SiO2 middle layer. Finally, copper(I) was introduced to the yolk–shell Fe3O4@Ethylated‐bPEI and the activity of the catalyst was evaluated for atom transfer radical polymerization (ATRP) of styrene, led to obtain the well‐defined polymer with relatively low polydispersity. The toxicity of the residual copper in the polymer product was a limiting issue for applicability of ATRP reactions especially for biological purposes. In this report, the copper content in the polymer was reduced to the excellent value of 1.1 ppm. Moreover, the magnetic isolation, recyclability, and remove the need for an external ligand were other advantages of the synthesized catalyst which makes it suitable for employing in ATRP reactions. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42337.  相似文献   
84.
Hepatitis B often progresses to decompensated liver cirrhosis requiring orthotopic liver transplantation (OLT). Although newer nucleos(t)ide analogues result in >90% viral and hepatitis activity control, severely decompensated patients still need OLT because of drug-resistant virus, acute exacerbation, or hepatocellular carcinoma. Acute hepatitis B is also an indication for OLT, because it can progress to fatal acute liver failure. After OLT, the hepatitis B recurrence rate is >80% without prevention, while >90% of transplant recipients are clinically controlled with combined hepatitis B immunoglobulin (HBIG) and nucleos(t)ide analogue treatment. However, long-term HBIG administration is associated with several unresolved issues, including limited availability and extremely high cost; therefore, several treatment protocols with low-dose HBIG, combined with nucleos(t)ide analogues, have been investigated. Another approach is to induce self-producing anti-hepatitis B virus (HBV) antibodies using an HBV envelope (HBs) antigen vaccine. Patients who are not HBV carriers, such as those with acutely infected liver failure, are good candidates for vaccination. For chronic HBV carrier liver cirrhosis patients, a successful vaccine response can only be achieved in selected patients, such as those treated with experimentally reduced immunosuppression protocols. The present protocol for post-OLT HBV control and the future prospects of newer treatment strategies are reviewed.  相似文献   
85.
采用胶柬毛细管电动色谱法分离测定了人血清白蛋白和人免疫球蛋白。结果表明,人血清白蛋白和人免疫球蛋白样量在10-500μ/mL范围内线性关系良好,相关系数r=0.9959~0.9988,迁移时间和峰面积的相对标准偏差分别小于2.04%和4.62%,回收率在92.2%-108.7%之间。建立的方法在优化条件下,可在5min内完成人血清白蛋白和人免疫球蛋白的分析测定。  相似文献   
86.
 Subchronic toxicity dietary studies were conducted in albino rats on the safety aspects of residual β-cyclodextrin in egg samples treated for cholesterol removal at concentrations of 250, 125 and 20 ppm for a period of 90 days. Daily food intake, body weight gain, relative organ weights, histopathology, haematology and serum enzyme activities were studied. The study however, did not reveal any toxicity at any of the levels tested. It can therefore be concluded from the present study that β-cyclodextrin-treated egg samples do not cause any toxicity. Received: 28 September 1999  相似文献   
87.
目的考察不同实验条件对静注人免疫球蛋白(pH 4)多聚体含量的影响及多聚体含量增加对家兔存活状态的影响。方法取静注人免疫球蛋白(pH 4),经干热破坏试验、湿热加速试验、紫外线照射试验、X射线照射试验及冰冻破坏试验,观察不同实验条件对其多聚体含量的影响;并取湿热加速试验和冰冻处理的样品注射家兔,观察多聚体含量增加对家兔存活状态的影响。结果静注人免疫球蛋白(pH 4)的多聚体含量随贮存温度的升高、时间的延长而增加,紫外线、X射线照射及冰冻处理均不影响多聚体含量;多聚体含量愈高,家兔存活状态愈差,多聚体含量达80%以上时,可致家兔死亡。结论高温可显著影响多聚体含量,多聚体含量增加与家兔存活状态呈负相关。  相似文献   
88.
The objectives were to determine the effects of dietary cation-anion difference (DCAD) fed to pregnant cows during the last 22 d of gestation on offspring acid-base balance, metabolism, growth, and health preweaning. A total of 132 nulliparous Holstein cows were enrolled at 250 (248 to 253) d of gestation in a randomized block design. Cows were blocked by genomic merit of energy-corrected milk yield and assigned randomly to diets varying in DCAD: +200 (P200, n = 43), ?50 (N50, n = 45), or ?150 (N150, n = 44) mEq/kg of dry matter (DM). Newborn calves (15 males and 28 females in P200, 22 males and 23 females in N50, and 18 males and 26 females in N150) were followed for the first 7 or 56 d of age if males or females, respectively. Measures of acid-base balance and concentrations of minerals in blood were measured in all calves on d 0 before colostrum feeding, and on d 1, 3, and 7. Each calf was fed 3.78 L of colostrum from the respective treatment, and apparent efficiency of IgG absorption was determined. All calves were weighed at birth, and females were weighed again at 21, 42, and 56 d of age. Concentrations in serum of total calcium (tCa), total magnesium (tMg), and total phosphorus (tP) were measured up to 56 d of age; intakes of milk and starter grain DM were measured daily from 21 to 56 d of age; and incidence of disease was recorded for the first 56 d of age in females. Treatment did not affect acid-base balance measured in all calves. Calves were born with metabolic and respiratory acidosis, which reversed by 1 d of age. In the first 24 h after birth, blood pH increased from 7.215 to 7.421 and bicarbonate from 26.2 to 31.7 mM, whereas partial pressure of CO2 decreased from 64.1 to 48.7 mm of Hg in all treatments. Maternal DCAD did not affect colostrum IgG content fed to calves (P200 = 95.0 vs. N50 = 91.0 vs. N150 = 97.1 ± 4.1 g/L) or apparent efficiency of IgG absorption (P200 = 33.1 vs. N50 = 33.1 vs. N150 = 34.2 ± 1.9%). Males were born heavier than females, but maternal DCAD did not affect birth weight of all calves (P200 = 37.7 vs. N50 = 37.3 vs. N150 = 37.8 ± 0.7 kg) or daily weight gain in females in the first 56 d of life (P200 = 0.80 vs. N50 = 0.81 vs. N150 = 0.77 ± 0.03 kg/d). Treatment did not affect intake of milk (P200 = 1.11 vs. N50 = 1.04 vs. N150 = 1.19 ± 0.06 kg/d) or starter grain DM (P200 = 0.27 vs. N50 = 0.27 vs. N150 = 0.21 ± 0.06 kg/d), or measures of feed efficiency. Treatment did not affect concentrations of minerals in serum, morbidity, or age at morbidity. Manipulating the DCAD of pregnant nulliparous dams during late gestation did not affect offspring performance in the first 2 mo of age.  相似文献   
89.
牛初乳中富含营养物质和多种活性成分,尤其是IgG的含量特别高。以产犊后48h内的牛初乳为原料,研究不同的超高压处理条件对牛初乳中IgG活性的影响,采用ELISA方法检测经过超高压处理后样品中IgG的活性。结果显示,在压力500MPa、温度35℃、时间20min条件下处理牛初乳,其IgG活性提高率达到最大。   相似文献   
90.
The activation and degranulation of immune cells play a pivotal role in allergic inflammation, a pathological condition that includes anaphylaxis, pruritus, and allergic march-related diseases. In this study, trifuhalol A, a phlorotannin isolated from Agarum cribrosum, inhibited the degranulation of immune cells and the biosynthesis of IL-33 and IgE in differentiated B cells and keratinocytes, respectively. Additionally, trifuhalol A suppressed the IL-33 and IgE-mediated activation of RBL-2H3 cells through the regulation of the TAK1 and MK2 pathways. Hence, the effect of trifuhalol A on allergic inflammation was evaluated using a Compound 48/80-induced systemic anaphylaxis mouse model and a house dust mite (HDM)-induced atopic dermatitis (AD) mouse model. Trifuhalol A alleviated anaphylactic death and pruritus, which appeared as an early-phase reaction to allergic inflammation in the Compound 48/80-induced systemic anaphylaxis model. In addition, trifuhalol A improved symptoms such as itching, edema, erythema, and hyperkeratinization in HDM-induced AD mice as a late-phase reaction. Moreover, the expression of IL-33 and thymic stromal lymphopoietin, inflammatory cytokines secreted from activated keratinocytes, was significantly reduced by trifuhalol A administration, resulting in the reduced infiltration of immune cells into the skin and a reduction in the blood levels of IgE and IL-4. In summarizing the above results, these results confirm that trifuhalol A is a potential therapeutic candidate for the regulation of allergic inflammation.  相似文献   
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