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11.
BACKGROUND: Breast milk contains many immunomodulatory factors (soluble CD14 (sCD14), IgA and cytokines) with the potential to influence infant immune development. OBJECTIVE: To determine if changes in breast milk omega-3 polyunsaturated fatty acid (n-3 PUFA) composition as a result of maternal dietary fish oil supplementation during pregnancy can modify levels of these immunological parameters in breast milk. METHOD: In a randomized controlled trial, 83 atopic women received either 4 g fish oil capsules (containing 3.7 g n-3 PUFA) (n = 40) or 4 g olive oil capsules (n = 43) from 20 weeks gestation until delivery. Breast milk was collected 3 days post-partum and fatty acids were analysed by gas liquid chromatography and IgA, sCD14 and cytokines (IL-5, IL-6, IL-10, TNF-alpha and IFN-gamma) were quantitated by ELISA or time resolved fluorescence (TRF). RESULTS: Omega-3 docosahexaenoic acid (DHA; 22:6n-3) and eicosapentaenoic acid (EPA; 20:5n-3) levels were significantly higher (P < 0.001) in breast milk from women supplemented with fish oil (n = 33, DHA mean 1.15%, SD 0.47% and EPA mean 0.16%, SD 0.07%) than in samples from the control group (n = 40, DHA mean 0.50%, SD 0.17% and EPA mean 0.05%, SD 0.02%). Breast milk arachidonic acid (AA; 20:4n-6) levels were significantly lower (P = 0.045) in the fish oil group (mean 0.55%, SD 0.12%) compared with the control group (mean 0.61%, SD 0.14%). Breast milk IgA was positively correlated with DHA (P = 0.046) and 22:5n-3 (P = 0.003), but inversely correlated with linoleic acid (LA; 18:2n-6) (P=0.034). Levels of sCD14 were also positively correlated with 22:5n-3 (P=0.009). Cytokines involved in IgA synthesis (IL-10 and IL-6) were also significantly correlated with both IgA and n-3 PUFA levels, although there were no differences in the levels of breast milk IgA, sCD14 or cytokines between study groups. CONCLUSION: Supplementation with fish oil during pregnancy significantly alters early post-partum breast milk fatty acid composition. omega-3 PUFA levels were positively associated with IgA and sCD14 levels, suggesting a relationship between fatty acid status and mucosal immune function.  相似文献   
12.
The present study investigated the phototoxic effect of bergamot oil and its photosensitive component, bergapten, on sunburn cell (SBC) production in guinea pig skin. The back skin was pretreated with bergamot oil or bergapten and exposed to monochromatic light under various conditions. After irradiation, skin specimens were excised, and histological sections were prepared. The number of sunburn cells in the interfollicular epidermis was counted. The SBC formation by bergamot oil or bergapten plus UVB radiation was the same as that without pretreatment with any photosensitizer. In contrast, a significant number of SBCs were induced by bergamot oil or bergapten plus UVA radiation, but no SBCs were found after the treatment with UVA alone. The result indicates that bergamot oil or bergapten was photosensitized by UVA irradiation. The SBCs were linearly increased in a UV-dose dependent manner. On the basis of the regression lines, an action spectrum and spectral peak for the photosensitizers plus UVA were obtained. The action spectrum for bergamot oil- and bergapten-induced SBC formation was in the ranges of 325–365 nm and 325–350 nm, and their spectral peaks were at 335–345 nm and 335–350 nm, respectively. The data are in good accordance with those estimated from skin erythema reactions. Therefore, counting SBCs is a very useful parameter for quantitative evaluation of phototoxicity.  相似文献   
13.
The antibacterial activity of the volatile oil of Nigella sativa seeds was studied against 37 isolates of Shigella dysenteriae 1, Shigella flexneri, Shigella sonnei and Shigella boydii and 10 strains of Vibrio cholerae and Escherichia coli. Most of the strains were clinically resistant to ampicillin, co-trimoxazole and tetracycline. All the strains tested showed promising sensitivity to the volatile oil. The minimum inhibitory concentration (MIC) of the volatile oil for Shigella, Vibrio and Escherichia strains tested was between 50–400 μg/mL.  相似文献   
14.
15.
N-3 fatty acids only delay early relapse of ulcerative colitis in remission   总被引:4,自引:0,他引:4  
Relapse prevention by dietary n-3 fatty acids (5.1 g/day) was studied in a double-blind, placebo-controlled trial of 64 patients with ulcerative colitis in remission and off steroids. 5-ASA compounds were stopped three months after randomization and clinical disease activity monitored for two years. Macroscopic and histologic activity and extension was assessed by colonoscopy at entry and at exit. Both treatment groups were well matched at start. Nine patients on placebo and eight on n-3 fatty acids stopped taking their medication prematurely. Actuarial relapse-free survival was improved by n-3 fatty acids only during months 2 and 3 (2P<0.05–0.01), but cumulative relapse rate at two years was similar for those taking placebo (18/33=55%) and n-3 fatty acids (18/31=58%). There was also no consistent difference in clinical, macroscopic, and histologic disease activity between treatment groups. The n-3 fatty acids temporarily retard, but do not prevent, relapse of ulcerative colitis.  相似文献   
16.
本实验用纯系CFW小鼠与Wistar大鼠建立“虚证”模型。以环核苷酸系统反应性为指标观察了肉桂挥发油的作用。通过气相色谱及气质联用等方法研究表明,本实验所提取的挥发油中桂皮醛含量约为92%。肉桂挥发油可显著降低“阳虚”——甲状腺素缺乏(甲减)模型升高了的cGMP系统反应性而使其降低了的耗O_2率升高;这是一种治疗作用。肉桂挥发油可显著升高“阴虚”——甲状腺素过多(甲亢)模型已升高了的cAMP系统反应性并使其升高了的耗O_2率进一步升高,这是一种恶化作用。这两种作用与中医对症治疗的原则是一致的。  相似文献   
17.
Objective and Design: Whilst the anti-microbial properties of tea tree oil (TTO) are established, the anti-inflammatory effects of TTO in human skin remain largely anecdotal and require evaluation. This study examined the effect of topically applied TTO on nickel-induced contact hypersensitivity reactions in human dorsal skin.Treatment: TTO (100%), a 5% TTO lotion, a placebo lotion (no TTO), or 100% macadamia oil were applied at days 3 and 5 after nickel exposure.Methods: The flare area and erythema index were measured on days 3, 5 and 7. The regulatory effects of TTO were also investigated on the proliferative response to nickel or polyclonal mitogens by peripheral blood mononuclear cells from nickel-sensitive and control subjects.Results: TTO (100%) significantly reduced the flare area and erythema index when compared to the nickel-only sites. With respect to the erythema index, the anti-inflammatory effects were predominantly, but not exclusively, seen in a subgroup of nickel-sensitive subjects with a prolonged development phase of nickel-induced contact hypersensitivity response. The 5% TTO lotion, the placebo lotion and the 100% macadamia oil were all without significant effect. TTO significantly inhibited proliferation to nickel but not to non-specific polyclonal mitogens by peripheral blood mononuclear cells from nickel-sensitive subjects.Conclusions: Topical application of 100% TTO may have therapeutic benefit in nickel-induced contact hypersensitivity in human skin. The mode of action of TTO requires further investigation, but may be an effect on the antigen presenting cells or the antigen presenting process in nickel-induced contact hypersensitivity, as well as vascular changes associated with this response.Received 14 February 2004; returned for revision 30 June 2004; accepted by J. S. Skotnicki 13 September 2004  相似文献   
18.
Studies on human T-cell lymphotropic virus types I (HTLV-I) and II (HTLV-II) are briefly reviewed from the viewpoint of molecular evolution, with special reference to the evolutionary rate and evolutionary relationships among these viruses. In particular, it appears that, in contrast to the low level of variability of HTLV-I among different isolates, individual isolates form quasispecies structures. Elucidating the mechanisms connecting these two phenomena will be one of the future problems in the study of the molecular evolution of HTLV-I and HTLV-II.  相似文献   
19.
Particle transport by oscillating flow in a tapered channel or in a tapered tube was computed from the complete equations of motion. These geometries represent a simplified model of the divergent flow field of the mammalian bronchial tree. The computed deformation profile of a line of particles, transported by the oscillatory motion, was compared with prior experimental results and analytical calculations. All three methods agree that there is transport in the divergent direction of the tube by an axial stream of steady drift in the core for moderately high frequency of oscillation (Womersley parameter in the range of 1 to 10). Bidirectional flow is established by an annular stream in the convergent direction, with no net flow on integral cycles of the oscillating fluid. At higher frequency, however, the steady stream transforms to a different shape in the tapered tube, with transport in the divergent direction nearer the walls of the tube, rather than in the core. Transport by the continuing streams with oscillatory ventilation of the respiratory tract should deliver medicinal aerosols of low intrinsic particle mobility to the peripheral regions of the lungs.  相似文献   
20.
胡萝卜籽挥发油的抗生育作用   总被引:3,自引:0,他引:3  
胡萝卜籽挥发油对小鼠有抗着床,抗早、中和晚期妊娠作用。对大鼠也有抗着床作用。挥发油中的萜类碳氢化合物部位,对小鼠皮下注射抗早期妊娠的ED_(50)为2.9ml/kg,甲地孕酮和hCG能明显逆转其作用;对假孕小鼠蜕膜瘤有抑制作用,此作用不能被甲地孕酮拮抗,皮下注射于早孕大鼠24、48小时后血浆孕酮浓度明显下降。以上提示其抗早孕作用机制可能与抑制孕酮合成和蜕膜反应有关。此外,挥发油碳氢部分无雌激素和抗雌激素活性,低浓度时对早孕大鼠离体子宫的收缩活动没有影响,高浓度则表现抑制作用。  相似文献   
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