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1.
The effect of extremely-low-frequency pulsed magnetic fields (PMF) on the response of human peripheral blood mononuclear cells to mitogenic stimulation is reported. We investigated 25 healthy control subjects. Mitogen-stimulated mononuclear cells were exposed to PMF for 72 h and an inhibition of 3H-thymidine uptake was observed in all but one subject. The degree of inhibition of 3H-thymidine uptake was as much as 60%. There was no significant difference between the blastogenic responses of mononuclear cells exposed to PMF for 12 h and control cultures. This study establishes an inhibitory effect of PMF on an in vitro measure of immune function.  相似文献   

2.
In the present study, intensive investigation was made on the effect of seaweed liquid fertilizer (SLF) of Codium decorticatum on the seed germination yield biochemical and pigment characteristic of Capsium annum under laboratory conditions and in pots. Different concentrations such as 10%, 20%, 30%, 40% and 50% of SLF were prepared using distilled water. The seeds were soaked in 10 h for each SLF concentration then placed in separate Petri plates. Similarly, water soaked seeds were used as controls. Application of a lower concentration (20%) of SLF Showed maximum seed germination, fresh weight, dry weight, root and shoot length, number of branches, leaf area, number of pods and content of total chlorophyll, chl a, and chl b, protein, carbohydrate and lipids were observed. Therefore, the results of the present study suggested that the SLF of C. decortianum could serve as an alternative bio-fertilizer as is eco-friendly, cost-effective, deliver substantial economic and environmental benefits to farmer.  相似文献   

3.
Summary (Gamma aminobutyric acid) GABA was applied to cultures of mouse neuroblastoma cells of different ages at concentrations ranging from 10-4 to 10-6 M. The cultures were exposed to GABA either in short term experiments for 2 h to 2 days or for longer periods by adding the substance twice within 10 days at 5-day intervals. The following effects were observed: (1) There was a strong proliferation of coated vesicles, appearing to derive from the Golgi complex and the rough endoplasmic reticulum (RER), and also showing all intermediate stages of fusion and pinching off from the plasma membranes. (2) In numerous areas, electron-dense material aggregated at the inner aspect of the plasma membrane and around small invaginations of the plasmalemma. (3) The number and area of specialized contacts increased between cells and their processes. (4) Similar to cultures free of GABA, varicosities and terminal swellings of the cells and their processes were filled with small round vesicles, 40–60 nm in diameter, or with smooth, very large, empty-appearing vesicular inclusions, or with flat pleiomorphic vesicles. In addition, mitochondria and some formations of the smooth endoplasmic reticulum (SER) appeared, and primitive contacts (symmetrical densities) were formed. (5) Dense-cored vesicles were found peripherally and linearly arranged, surrounded by an electron-dense substance. (6) Electron-dense material of unknown origin was seen between cells or their processes near the peripherally arranged dense-cored vesicles. Exogenous GABA may play a specific role in the early stages of synaptogenesis, since it showed a positive effect on the neuroblastoma cells, which in the absence of GABA are only capable of forming primitive or immature presynaptic elements. The significance of the peripheral accumulation of dense-cored vesicles, accompanied by an amorphous, electron-dense substance occurring both intra- and extracellularly is discussed.  相似文献   

4.
Aims: Eating raw or insufficiently cooked bivalve molluscs contaminated with human noroviruses (NVs) can result in acute cases of gastroenteritis in humans. Manila clams (Ruditapes philippinarum) are particularly prone to exposure to NVs due to the brackish environment in which they are farmed which is known to be susceptible to human faecal contamination. High hydrostatic pressure processing (HHP) is a food treatment technique that has been shown to inactivate NV. Methods and results: In this study we investigated the ability of HHP to inactivate murine norovirus (MNV‐1), a recognised surrogate for NV, in experimentally contaminated manila clams. Pools of contaminated live clams were subjected to hydrostatic pressure ranging from 300 to 500 MPa for different time intervals of between one and 10 min. The trial was repeated three times, at monthly intervals. Conclusions: Virus vitality post‐treatment was assessed and the data obtained indicates that the use of high hydrostatic pressures of at least 500 MPa for 1 min was effective in inactivating MNV‐1. Significance and Impact of the Study: HHP results to be an effective technique that could be applied to industrial process to obtain safe Manila clams ready to eat.  相似文献   

5.
Interleukin I (IL-1) is a lymphocyte stimulant released by human monocytes cultured for 18–24 hours in tissue culture medium containing 5% serum and the non-specific immunostimulant lipopolysaccharide (LPS). Human IL-1 is found in the conditioned medium in a low molecular weight (~ 13,000) and a high molecular weight (~ 85,000) form. The high MW activity may result from the formation of a complex between IL-1 and serum constituents. During the course of purification, the low MW IL-1 activity is often recovered in a high MW form. Hollow fiber diafiltration and membrane ultrafiltration has been found to rapidly separate low MW IL-1 from all measurable protein with a yield of 4% of the original activity. The IL-1 which converts to the high MW form during the purification is recoverable, 21% of the original activity, but contains small amounts of serum proteins. Isoelectric focusing (IEF) of the low MW IL-1 resulted in a very highly purified sample which was analyzed by polyacrylamide gel electrophoresis (PAGE). Utilizing a new staining procedure which detects less than 1 ng of protein per band, the IEF-purified IL-1 revealed trace quantities ( < 1 ng) of a slowly migrating protein similar to immunoglobulin and no other bands. There were no bands which corresponded with the known electrophoretic mobility of IL-1. Since the samples applied to the gel contained significant biological activity, this result implies that human IL-1 is biologically active in picogram quantities.  相似文献   

6.
比较广西北部湾石莼(Ulva lactuca L.)、海带(Laminaria japonica)、裙带菜(Undaria pinnatifida Surin-gar)、紫菜(Porphyra)的单糖组成及抗氧化活性的差异,揭示多糖结构与其体外抗氧化活性的关系。利用PMP柱前衍生化HPLC分析海藻多糖的单糖组成,采用羟自由基清除试验、超氧阴离子自由基清除试验及DPPH自由基清除试验指征其体外抗氧化活性,结果表明,4种海藻多糖的单糖组成在主成分空间分布离散,石莼及紫菜主要由葡萄糖组成,海带主要由甘露糖组成,裙带菜则主要由半乳糖组成;其体外抗氧化活性存在显著差异,裙带菜多糖对DPPH的清除能力(半抑制浓度IC50值为0. 56±0. 02 mg/mL)显著高于其他3种海藻多糖;石莼、裙带菜与海带对羟自由基均有较强的清除活性,而紫菜多糖对羟自由基的清除能力较差(IC50值为26. 59±0. 98mg/mL);石莼与裙带菜对超氧阴离子的清除活性较强,显著高于海带与紫菜,其中石莼显著高于裙带菜,IC50值分别为1. 61±0. 17、2. 73±0. 06 mg/mL。相关性分析及冗余分析结果表明,对抗氧化活性影响较为显著的因子为葡萄糖(Glc)、核糖(Rib)、木糖(Xyl)(P <0. 01)。  相似文献   

7.
We examined the effects of berberrubine, a protoberberine alkaloid, on interleukin-8 (IL-8) and monocyte chemotactic protein-1 (MCP-1) expression in a human retinal pigment epithelial cell line (ARPE-19) stimulated with interleukin-1beta (IL-1beta) or tumor necrosis factor alpha (TNF-alpha). ARPE-19 cells were cultured to confluence. Berberrubine and IL-1beta or TNF-alpha were added to the medium. IL-8 and MCP-1 protein concentrations were measured using enzyme-linked immunosorbent assay. IL-8 and MCP-1 mRNA were measured by real time polymerase chain reaction. Nuclear factor kappaB (NF-kappaB) translocation was examined by immunofluorescent staining/microscopy. Berberrubine dose-dependently inhibited IL-8 and MCP-1 protein levels in the media and mRNA expression of the cells stimulated with IL-1beta or TNF-alpha. Immunofluorescent staining/microscopy of NF-kappaB in the nucleus of unstimulated cells was faint (51+/-14 arbitrary units). Fluorescein was dense (215+/-42 or 170+/-24 arbitrary units, respectively) 30 min after stimulation with IL-1beta or TNF-alpha and was decreased to 62+/-18 or 47+/-16 arbitrary units, respectively, by berberrubine. Berberrubine dose-dependently inhibited IL-8 and MCP-1 expression and protein secretion induced by IL-1beta or TNF-alpha. Possibly, the effect on chemotactic factors may be via suppression of NF-kappaB translocation.  相似文献   

8.
Lei J  Wang Z  Hui D  Yu W  Zhou D  Xia W  Chen C  Zhang Q  Wang Z  Zhang Q  Xiang AP 《Cellular immunology》2011,271(1):147-156
Mesenchymal stem cells (MSCs) have potent regulatory effects on immune and inflammatory responses. Recently the findings of functional TLR expression on MSC implicates these receptors in the function established for MSCs. Here we specially investigated the effects of TLR2, 4 ligation in mice MSC on migration, modulation of allogeneic mixed lymphocytes reaction (allo-MLR) and inducing Treg cells. We demonstrated that ligation of TLR2, but not TLR4, could significantly inhibit migration of MSC, impair MSC-mediated immunosuppression on allo-MLR, and reduce MSC-mediated expansion of CD4+CD25+Foxp3+ regulatory T cells. Compared with TLR4 activated MSCs and non-TLR activated MSC, TLR2 activation induced a relatively lower level of CXCL-10 mRNA and protein expressions which has been elucidated to act in concert with other soluble factor in MSC-mediated immunomodulation. These data indicate that TLR2 and TLR4 ligation had different effects on immunomodulatory capability of murine BMSCs, which should be considered in their use for treating inflammatory diseases.  相似文献   

9.
Photoinhibition of photosynthesis in the brown alga, Dictyota dichotoma, was studied with a PAM fluorometer (Walz, Effeltrich, Germany) and a homemade oxygen measuring device. As a measure of fluorescence, Fv/Fm, and for the photosynthetic yield, ΔF/Fm', were used. Oxygen measurements show clearly that the observed degree, as well as the time course, of photoinhibition depends on the fluence rate of the light used to measure changes of the production rate. After photoinhibition of photosynthesis the depression of oxygen production caused by non-saturating fluence rates was generally much more pronounced than that caused by saturating or nearly saturating fluence rates. At minimal photoinhibition the initial slope and the convexity of the fluence rate-response curve of oxygen evolution decrease, whereas the level of light saturation decreases only after strong photoinhibition. Nevertheless, at different degrees of photoinhibition, changes in the degree of the upper bending of the fluence rate-response curve of oxygen production are also linearly correlated to changes in the fluorescence ratios (Fv/Fm and ΔF/Fm'). The action spectrum of photoinhibition, calculated on the basis of changes of Fv/Fm, indicates that the reaction center of PS I is not involved in photoinhibition. The lower effectiveness of blue light in comparison to effects of green and red light may be due to chloroplast displacement, as in the so-called strong light position, the light absorbed by the thalli in vivo is decreased.  相似文献   

10.
The effect of diets enriched with fat containing different fatty acids on glucose and glutamine metabolism of mesenteric lymph nodes lymphocytes, spleen, and thymus and lymphocyte proliferation was examined. The following fat-rich diets were tested: (1) standard chow (CC); (2) medium chain saturated fatty acids (MS)—coconut fat oil; (3) long chain saturated fatty acids (LS)—cocoa butter; (4) monounsaturated fatty acids (MU)—canola oil (n-9); (5) polyunsaturated fatty acids (PU)—soybean oil (n-6). Of the fat-rich diets tested, MS was the one to present the least pronounced effect. Lymphocyte proliferation was reduced by LS (64 per cent), MU (55 per cent), and PU (60 per cent). Hexokinase activity was enhanced in lymph node lymphocytes by PU (67 per cent), in the spleen by MS (42 per cent), and in the thymus by PU (30 per cent). This enzyme activity was reduced in the spleen (33 per cent) by LS and MU (35 per cent). In the thymus, this enzyme activity was reduced by LS (26 per cent) and MU (13 per cent). Maximal phosphate-dependent glutaminase activity was raised in lymphocytes by MS (70 per cent) and MU (20 per cent). This enzyme activity, however, was decreased in lymphocytes by PU (26 per cent), in the spleen by LS (15 per cent), and in the thymus by MU (44 per cent). Citrate synthase activity was increased in lymphocytes by MU (35 per cent), in the spleen by LS (56 per cent) and MU (68 per cent), and in the thymus by LS (42 per cent). This enzyme activity was decreased in lymphocytes by PU (24 per cent) only. [U-14C]-Glucose decarboxylation was raised by all fat-rich diets; MS (88 per cent), LS (39 per cent), MU (33 per cent), and PU (50 per cent), whereas [U-14C]-glutamine decarboxylation was increased by LS (53 per cent) and MU (55 per cent) and decreased by MS (17 per cent). The results presented indicate that the reduction in lymphocyte proliferation due to LS, LU and PU could well be a consequence of changes in glucose and glutamine metabolism. Copyright © 1998 John Wiley & Sons, Ltd.  相似文献   

11.
采用生物活性法和/或酶联免疫吸附法以及乳酸脱氢酶释放法,研究了人类疱疹病毒6型(HHV-6)南京地方株CNS对人外周血单个核细胞(PBMCs)的IL—6、IL-8的诱生和NK活性的影响,并与国外的GS株作比较。结果发现,HHV—6CN8、GS两株病毒感染均可诱导PBMCs产生IL-8,48h达到峰值。两株病毒所诱生的IL-8水平并无显著性差异(P>0.05),并可抑制IL-6的产生,但GS株的抑制作用强于CNS株(P<0.05)。HHV-6体外感染12~24h可以增强NK活性,且CN8株诱导的NK活性高于GS株(P<0.05),之后NK活性逐渐减弱。以上结果提示:HHV-6感染可以通过诱生细胞因子和改变NK活性而影响人的免疫功能,而A组的GS株对免疫功能的抑制作用大于B组的CN8株。  相似文献   

12.
Hydroxytyrosol‐rich extract (HRE) and hydroxytyrosol‐rich olive mill wastewater (HROMW) were used as exogenous growth enhancers to stimulate tomato seedling vigor. The tomato seeds soaking in 10% w/v HROMW or HRE solutions were optimum in maximally enhancing seedling performance according to biochemical seed vigor parameters. Biochemical parameters as the average glucose‐6‐phosphate dehydrogenase (G6PDH) activity in HRE‐treated seeds (915.11 nmoles min?1 mg?1 protein) was higher than control (629.58 nmoles min?1 mg?1 protein) and correlated with the increased phenolic content (3530 μg g?1 fw) and 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH)‐based antioxidant activity (70.60%), respectively. Some key enzymes, guaiacol peroxidase (GPX) (6100.65 nmoles min?1 mg?1 protein) and catalase (2.04 μmoles min?1 mg?1 protein), were also higher in response to treatments and correlated with enhanced phenolic content and antioxidant activity. This study supports the hypothesis that the exogenous phenolic application stimulates the pentose phosphate pathway through an over‐expression of endogenous phenolic synthesis and an increase in free‐radical scavenging antioxidant activity. Therefore, the current study indicates the enhancement of seed vigor by HRE especially and HROMW as reflected by the stimulation of biochemical responses.  相似文献   

13.
MDP, a synthetic muramyl dipeptide, is capable of increasing the primary in vitro antibody response, to sheep erythrocytes, of purified B cells restored with a monokine and helper T cell factors, including Interleukin 2 and the late-acting T cell replacing factor (TRF). First, the possibility that the adjuvanticity of MDP could be due to the elaboration of Interleukin 1, caused by its effect on macrophages, was excluded. In addition, a kinetic study showed that the effect of MDP was greater when added later, concomitantly with or one day after the helper T cell factors. Therefore, it appears that MDP acts directly on B cells, in a late stage of their differentiation to antibody-producing cells.  相似文献   

14.
Saikosaponin‐d (Ssd) is a triterpene saponin derived from the medicinal plant, Bupleurum falcatum L. (Umbelliferae). Previous findings showed that Ssd exhibits a variety of pharmacological and immunomodulatory activities including anti‐inflammatory, anti‐bacterial, anti‐viral and anti‐cancer effects. In the current study we have investigated the effects of Ssd on activated mouse T lymphocytes through the NF‐κB, NF‐AT and AP‐1 signaling pathways, cytokine secretion, and IL‐2 receptor expression. The results demonstrated that Ssd not only suppressed OKT3/CD28‐costimulated human T cell proliferation, it also inhibited PMA, PMA/Ionomycin and Con A‐induced mouse T cell activation in vitro. The inhibitory effect of Ssd on PMA‐induced T cell activation was associated with down‐regulation of NF‐κB signaling through suppression of IKK and Akt activities. In addition, Ssd suppressed both DNA binding activity and the nuclear translocation of NF‐AT and activator protein 1 (AP‐1) of the PMA/Ionomycin‐stimulated T cells. The cell surface markers like IL‐2 receptor (CD25) were also down‐regulated together with decreased production of pro‐inflammatory cytokines of IL‐6, TNF‐α and IFN‐γ. These results indicate that the NF‐κB, NF‐AT and AP‐1 (c‐Fos) signaling pathways are involved in the T cell inhibition evoked by Ssd, so it can be a potential candidate for further study in treating T cell‐mediated autoimmune conditions. J. Cell. Biochem. 107: 303–315, 2009. © 2009 Wiley‐Liss, Inc.  相似文献   

15.
We generated and characterized novel antibody-cytokine fusion proteins (“immunocytokines”) based on murine interleukin-7 (IL7), an immunomodulatory protein which has previously shown anti-cancer activity in preclinical models and whose human counterpart is currently being investigated in clinical trials. The sequential fusion of the clinical-stage antibody fragment scFv(F8), specific to a tumor-associated splice isoform of fibronectin, yielded an immunocytokine (termed “F8-mIL7”) of insufficient pharmaceutical quality and in vivo tumor targeting performance, with a striking dose dependence on tumor targeting selectivity. By contrast, a novel immunocytokine design (termed “F8-mIL7-F8”), in which two scFv moieties were fused at the N- and C-terminus of murine IL7, yielded a protein of excellent pharmaceutical quality and with improved tumor-targeting performance [tumor: blood ratio = 16:1, 24 h after injection]. Both F8-mIL7 and F8-mIL7-F8 could induce tumor growth retardation in immunocompetent mice, but were not able to eradicate F9 tumors. The combination of F8-mIL7-F8 with paclitaxel led to improved therapeutic results, which were significantly better compared to those obtained with saline treatment. The study indicates how the engineering of novel immunocytokine formats may help generate fusion proteins of acceptable pharmaceutical quality, for those immunomodulatory proteins which do not lend themselves to a direct fusion with antibody fragments.  相似文献   

16.
17.
Effect of feeding 4.23, 16.94 and 27.53 mg of retinol daily for 10 days on the liver lipids of adult rats has been studied. Feeding of different amounts of retinol produced dose dependent toxicity symptoms in rats. Retinol feeding resulted in significant elevations of liver total lipids, total fatty acids, and glycerides, The amounts of liver esterified cholesterol were significantly raised in rats fed different amounts of retinol. Acetate-1-14C incorporation was increased in liver total cholesterol of rats fed 27.53 mg retinol and in free cholesterol of all retinol fed rats. Total 14C activity of hepatic triglycerides of retinol fed rats was the same as that of control, but their specific activity was decreased. Significant alterations were noted in phosphatidyl serine, lysophosphatidyl choline, lysophosphatidyl ethanolamine, sphingomyelin, phosphatidyl choline, phosphatidyl ethanolamine and phosphatidic acid and polyglycerophosphate fractions in liver rats fed different amounts of retinol.  相似文献   

18.
It is known that exogenous RNA molecules can be taken up by eukaryotic cells and can exert a variety of biological effects both in vitro and in vivo. The modulation of human lymphocytes by exogenous RNAs has medical implications. The exogenous RNA used in this study was obtained from lymphoid organs of animals immunized with the synthetic peptide p12 of HIV-1 and was referred to as p12-RNA. Human lymphocytes were transfected with the p12-RNA and the transfer of immunoreactivity of p12 was assessed by the lymphocyte proliferation and the leukocyte adherence inhibition assays. Our results indicate that the transfer of cellular immune response to the p12 occurred in 9 donors (60%) who were named responsive individuals whereas 6 donors (40%) were non-responsives. We also found that the calcium phosphate-mediated RNA uptake method is effective in converting non-responsive into responsive donors. The calcium phosphate-mediated RNA uptake may also be used to increase the efficiency of RNA transfection in other models with medical implications and to contribute to a better understanding of the molecular events involved in the uptake of RNA. Our findings give support for the use of exogenous RNAs obtained from lymphoid organs of immunized animals with synthetic peptides of HIV-1 in the immune reconstitution of individuals infected with HIV-1.  相似文献   

19.
目的:探究腹腔镜结肠癌根治术患者采用全麻复合硬膜外麻醉的效果及对相关指标的影响。方法:选取120例于2016年9月到2018年10月期间在我院进行腹腔镜结肠癌根治术的患者,按随机数字表法分为对照组(n=60)和复合组(n=60),对照组采用全麻,复合组采用全麻复合硬膜外麻醉。观察两组患者的麻醉效果;记录两组患者麻醉诱导前(T_0)、气腹前(T_1)、气腹后15 min(T_2)、气腹结束后(T_3)和出室即刻(T_4)的舒张压(DBP)、收缩压(SBP)和心率(HR)的变化;手术前、麻醉复苏前和术后1天的胰岛素抵抗指数(IR)、血糖水平(BS)、肾上腺素(AD)以及血清皮质醇(Cor)水平的变化;麻醉前、麻醉后2 h、术后1天和术后3天的CD3~+、CD4~+、CD4~+/CD8~+的水平变化。结果:复合组患者的麻醉诱导时间、自主呼吸恢复时间和苏醒时间明显短于对照组,麻醉维持时间明显长于对照组(P0.05)。复合组患者在T_2、T_3、T4时间点的DBP、SBP和HR明显低于对照组(P0.05)。麻醉复苏前和手术后1天,复合组患者的IR、BS、AD、Cor的水平明显低于对照组(P0.05)。麻醉后2 h、术后1天和术后3天的CD3~+、CD4~+、CD4~+/CD8~+明显高于对照组(P0.05)。结论:对腹腔镜结肠癌根治手术患者进行全麻符合硬膜外麻醉可以提高麻醉效果,减少对血流动力学的影响,减轻应激反应,减少对患者细胞免疫功能的影响。  相似文献   

20.
SYNOPSIS. The effect of temperature on photoaccumulation and photophobic response of Volvox aureus were studied. The algae exhibited positive photoaccumulation at room temperature and negative at low temperature. When stimulated with light of intermediate intensiy (~ 5 × 103 lux), the phobic response of the algae consisted of a decrease in the frequency or the cessation of flagellar movement in the anterior cells. At room temperature, an increase in light intensity elicited the phobic response, whereas at low temperature a decrease in light intensity was the effective stimulus. The phobic response lasted only a few seconds. The positive and negative photoaccumulations of the algae could be explained by the brief cessation of flagellar movement in the anterior cells, elicited by an increase of stimulus light at room temperature or a decrease of stimulus at low temperature.  相似文献   

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