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摘要： 目的 研究表達型質(zhì)粒載體 pMG36e 在大腸桿菌 JM109 和乳酸乳球菌 MG1363 兩種宿主菌中的遺傳穩定性并觀(guān)察紅霉素對其穩定性的影響。
方法 按經(jīng)典質(zhì)粒遺傳穩定性測定方法，在有選擇壓力（加紅霉素）和無(wú)選擇壓力的條件下，測定 pMG36e 質(zhì)粒在大腸桿菌 JM109 和乳酸乳球菌 MG1363 中的遺傳穩定率。
結果 pMG36e 質(zhì)粒在大腸桿菌 JM109 中連續傳至 120 代時(shí)，在有選擇壓力的條件下，質(zhì)粒穩定率保持在 100% ；無(wú)選擇壓力的條件下為 96% ； pMG36e 質(zhì)粒在乳酸乳球菌 MG1363 中連續傳至 100 代時(shí)，在有選擇壓力和無(wú)選擇壓力的條件下，質(zhì)粒穩定率均為 98% 。
結論 pMG36e 質(zhì)粒在兩種宿主菌中均具有較好的遺傳穩定性。紅霉素對 pMG36e 質(zhì)粒的遺傳穩定性無(wú)顯著(zhù)影響。
關(guān)鍵詞： 質(zhì)粒 遺傳穩定性 紅霉素
中圖分類(lèi)號： Q782 文獻標識碼： A
Study of the genetic stability of expression plasmid vector pMG36e in host bacteria
Wang Chuan ， Zhang Chao-wu ， Du Jiang
Department of Medical Technology, West china School of Public Health,Sichuan University, Chengdu 610041, China
Abstract: Objective To study the genetic stability of expression plasmid vector pMG36e in Escherichia coli JM109 and Lactococcus lactis MG1363/36e and observe the effect of erythomycin for its stability. Methods We used classical method to determine the genetic stable rates of pMG36e in E.coli JM109 and Lactococcus lactis MG1363/36e with or without erythomycin selective pressure. Results When E.coli JM109 were continuously incubated to 120 generations, its pMG36e genetic stable rates were 100% and 96% respectively with or without erythomycin selective pressure. When Lactococcus lactis MG1363/36e were continuously incubated to 100 generations, its pMG36e genetic stable rates were the same 98%, with or without erythomycin selective pressure. Conclusion pMG36e had good genetic stability in this two hosts. Erythomycin selective pressure had no significant effect for the genetic stability of pMG36e.
Key words: plasmid, genetic stability, erythomycin
鋅對應激大鼠海馬金屬硫蛋白亞型表達的調控作用及機制研究
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陳偉強 程義勇 李樹(shù)田 王冬蘭 于志杰 洪燕
軍事醫學(xué)科學(xué)院衛生學(xué)環(huán)境醫學(xué)研究所，天津 300050 |
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摘要：目的 觀(guān)察不同鋅攝入水平對應激大鼠海馬腦區不同金屬硫蛋白亞型表達的影響。
方法 將 Wistar 雄性大鼠隨機分為 8 組：正常對照組、對喂組、缺鋅組和補鋅組及其相應的應激組，分別給予正常飼料、缺鋅飼料和補鋅飼料，以缺鋅動(dòng)物當日的飼料攝入量作為對喂動(dòng)物次日的給料量。動(dòng)物喂飼 1 周后開(kāi)始束縛應激，持續 4 周。以血紅蛋白鎘飽和法測定腦組織金屬硫蛋白含量，分離海馬提取總 RNA ，以 RT-PCR 檢測金屬硫蛋白亞型 MT-1 mRNA 和 MT-3 mRNA 。 結果 缺鋅動(dòng)物出現血鋅含量明顯降低，腦組織金屬硫蛋白含量和海馬金屬硫蛋白 mRNA 的表達均出現降低，但其表達在缺鋅應激組動(dòng)物仍有明顯升高；而補鋅動(dòng)物金屬硫蛋白的表達有所增加，補鋅應激組動(dòng)物的表達增加更加明顯。缺鋅和缺鋅應激組動(dòng)物的血漿皮質(zhì)醇、 IL-1 、 IL-6 和 NO 水平也較其它組顯著(zhù)升高。 結論 缺鋅可降低動(dòng)物腦和海馬組織中金屬硫蛋白的表達，但缺鋅動(dòng)物在接受應激刺激后，金屬硫蛋白的表達仍可明顯增加；而補鋅可增加金屬硫蛋白的表達，補鋅應激使腦組織中金屬硫蛋白的表達升高更為顯著(zhù)；應激對動(dòng)物的損傷作用與其鋅營(yíng)養狀況有關(guān)，缺鋅可降低機體對應激的抵抗能力。
關(guān)鍵詞： 束縛應激 金屬硫蛋白 鋅 皮質(zhì)醇
中圖分類(lèi)號： R151.3 Q513 Q581 文獻標識碼：
Effects of zinc on the expression of metallothionein isoforms in hippocampus of stressed rats
Chen Wei-qiang, Cheng Yi-yong, Li Shu-tian, Wang Dong-lan, et al.
Institute of Health and Environmental Medicine, Academy of Military Medical Sciences, Tianjin 300050, China
Abstract: Objective This study was conducted to evaluate the effects of different doses of zinc on the expression of metallothionein isoforms in hippocampus of stressed rats. Methods The animal model of psychological stress was developed by restraint stress for four weeks. Wistar rats were randomly assigned to eight groups as follows: control group, zinc deficiency group, pair-feed group, zinc complementarity group and their corresponding stressed groups. Results In zinc deficiency group, plasm zinc content was decreased, while in zinc complementarity group it's slightly increased. On the one hand, the expressions of metallothionein in brain and MT-1 mRNA , MT-3 mRNA in hippocampus were downregulated in zinc deficiency group, however, their expressions were evidently enhanced in stressed zinc deficiency group. On the other hand, inductions of metallothionein and it's mRNAs in zinc complementarity group were increased, furthermore, stressed zinc complementarity group has more significantly yield of metallothionein and it's mRNAs. In addition, the levels of plasma cortisol, IL-6, IL-1 and NO were increased clearly in zinc deficiency group and stressed zinc deficiency group. Conclusion Our results suggested that zinc deficiency may decrease while zinc complementarety increase the expressions of metallothionein in brain and MT-1 mRNA, MT-3 mRNA in hippocampus, moreover, stress can increased their expressions dramatically. The impairment of stress on body may be involved with the nutrition status of zinc, and zinc deficiency can lower the body's resistibility to stress. Key words: restraint stress, metallothioneins, zinc, cortisol
基金項目： 國家自然科學(xué)基金資助項目（ No. 30100149 ）
作者簡(jiǎn)介： 陳偉強，男，博士研究生
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BALB/c 小鼠食物過(guò)敏動(dòng)物模型的實(shí)驗研究
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呂相征 劉秀梅 郭云昌 楊曉光
中國疾病預防控制中心營(yíng)養與食品安全所，北京 100050 |
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摘要：目的 BALB/c 小鼠作為食物過(guò)敏動(dòng)物模型的可行性也一直存在爭議，本研究探討 BALB/c 小鼠作為食物過(guò)敏動(dòng)物模型的可行性。
方法 對相應試驗組動(dòng)物分別腹腔注射 0.25ml 20mg/ml 卵清蛋白（ OVA ）、牛血清白蛋白（ BSA ）、大豆胰蛋白酶抑制劑（ TI ）和馬鈴薯酸性磷酸酶（ PAP ）共兩次，間隔為一周。檢測血漿中的組胺水平和血清中特異 IgE 抗體含量，同時(shí)進(jìn)行 皮膚過(guò)敏反應實(shí)驗（ PCA ）。
結果 OVA 、 BSA 、 TI 及 PAP 組 32 倍稀釋血清中均可檢測到特異 IgE 抗體； 血漿中組胺水平較對照組顯著(zhù)升高。 常見(jiàn)致敏食物蛋白質(zhì) OVA 和 TI 、 不常見(jiàn)致敏食物蛋白質(zhì) BSA 和 無(wú)致敏史食物蛋白質(zhì) PAP 均可致使 BALB/c 小鼠產(chǎn)生的過(guò)敏反應。
結論 BALB/c 小鼠不適合作為食物過(guò)敏動(dòng)物模型，本研究為解決 BALB/c 小鼠是否可以作為食物過(guò)敏動(dòng)物模型的爭議提供了理論依據。
關(guān)鍵詞：食物過(guò)敏 動(dòng)物模型 BALB/c 小鼠
中圖分類(lèi)號： R155.3 文獻標識碼： A
Assessment of the BALB/c mice as a suitable animal model for the investigation of food allergy
Lu Xiang-zheng, Liu Xiu-mei, Guo Yun-chang, Yang Xiao-guang
Institute of Nutrition and Food Safety, Chinese Center for Disease Control and Prevention, Beijing 100050, China
Abstract: Objective This study was to develop a suitable model for the investigation for food allergy. Methods BALB/c mice were dosed by intraperitoneally with Ovalbumin, Beef serum albumin , Trypsin inhibitor or Potato acid phosphatase respectively (0.25ml 20mg/ml) on day 0 and again on day 7. Control group was dosed with PBS. Sera form individual animals were analysed for specific IgE and Passive cutaneous anaphylaxis tests . Additionally, the level of histamine in plasma were detected. Results The high titres of specific IgE (1:32) could be provoked in test groups compared with control group. In addition, the level of histamine in plasma of test groups was higher than that in the control group. But there was no statistical significance between group food allergen and group Potato acid phosphatase. Conclusion Although allergic action of BALB/c mice could be provoked, the situation of the allergic action of BALB/c mice to the proteins was very different with the human being. T he BALB/c mice could not be a suitable model for the investigation for food allergy.
Key words: food allergy, animal model, BALB/c mice
基金項目：國家高技術(shù)研究發(fā)展計劃 “863” （ No.2001AA212291 及 2002AA212041 ）； 國家重點(diǎn)基礎研究發(fā)展規劃 “973” （ No. 001CB109007 ）
作者簡(jiǎn)介：呂相征，男，博士研究生
1 通訊作者：劉秀梅，女，研究員，博士生導師 |
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