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1.
艾蒿花粉主要变应原的分离、纯化与鉴定   总被引:6,自引:0,他引:6  
目的 对我国蒿属花粉中常见、重要的变应原艾蒿花粉进行分离、鉴定与纯化。方法采用不同的提取液得到艾蒿花粉粗浸液 ,经饱和 (NH4 ) 2 SO4 分级沉淀后用聚丙烯酰胺凝胶电泳 (SDS PAGE)分离蛋白质组分 ,并用凝胶成像系统测定各组分的相对分子质量 (Mr) ;采用Westernblot鉴定其主要及次要变应原 ;通过DEAE CelluloseDE 32离子交换层析 (ionexchangechromatography ,IEC)和SephadexG 75凝胶层析 (gelchromatography)对艾蒿花粉变应原进行纯化。结果 分离后得到 2 0多种蛋白质组分 ,其中Mr 为 5 8× 1 0 3、38× 1 0 3、2 5× 1 0 3、2 0× 1 0 3、1 6× 1 0 3等 5个条带蛋白含量最丰富 ;分离到的蛋白质组分中有 9种蛋白能与确诊的蒿属花粉过敏患者血清中蒿属花粉特异性IgE结合 ,其中Mr 为 6 2× 1 0 3、4 3× 1 0 3、38× 1 0 3的蛋白条带的结合率最高 ;经纯化后仅得到Mr 为 6 2× 1 0 3的主要变应原。结论 艾蒿花粉的主要变应原Mr 分别为 6 2× 1 0 3、4 3× 1 0 3和 38× 1 0 3,层析技术可以对Mr 为6 2× 1 0 3的主要变应原成分进行纯化。  相似文献   

2.
目的对我国南方常见的棕榈科植物王棕花粉(Roystonea regia pollen)变应原蛋白进行分离、分析与鉴定,为标准化变应原疫苗的研制提供基础。方法取常规方法制备的王棕花粉浸出液,采用SDS.PAGE分离王棕花粉蛋白质组分,测定其相对分子量,同时用10例对王棕花粉过敏的患者血清作Western-blot鉴定其变应原及主要变应原成分。结果SDS.PAGE显示王棕花粉有10条可辨蛋白带,其中主要条带有8条,分别为100000、66000、38000、36000、29000、30000、24000、16000和14000Mr,Western—blot结果表明,10例王棕花粉过敏患者血清全部呈阳性反应,有66000、24000、16000和14000Mr共4条致敏条带,其中分子量在16000和14000Mr的蛋白为主要变应原。结论王棕花粉变应原的分析与鉴定为临床王棕花粉变态反应疾病的诊断和治疗奠定了基础。  相似文献   

3.
姚敏 《基础医学与临床》2011,31(9):1036-1039
 【摘要】 目的 对重阳木花粉变应原蛋白进行分析、鉴定与纯化。方法 提取这重阳木花粉的粗提液,通过十二烷基硫酸钠-聚丙烯酰胺凝胶电泳(SDS - PAGE)分离粗提液蛋白质组分并测定其分子量,收集过敏病人血清,采用免疫印迹(Western - blotting)法鉴定其变应原成分,通过离子交换层析对重阳木花粉变应原进行初步纯化和免疫印迹鉴定。结果 重阳木花粉有18条主要蛋白带,12 000Mr和14 000Mr为重阳木花粉特异性变应原;通过离子交换层析方法纯化出重阳木花粉分子量为12 000Mr和14 000Mr的变应原主要分布在II峰中。结论 对重阳木花粉变应原进行了初步的分离、鉴定和纯化,为临床重阳木花粉过敏疾病的诊断和治疗奠定了基础。  相似文献   

4.
青蒿花粉变应原Art a1基因的克隆、表达及特性鉴定   总被引:2,自引:1,他引:1  
目的克隆、表达和鉴定青蒿花粉变应原Arta1。方法在成功构建青蒿花粉cDNA文库的基础上,用蒿属花粉过敏患者的阳性混合血清进行免疫学筛选,所获阳性克隆亚克隆入pET24a(+),经IPTG诱导表达后,通过Ni2+亲和层析柱对重组变应原进行纯化,并采用Westernblot和ELISA检测其IgE结合活性。结果选用阳性血清从青蒿花粉cDNA文库中筛选到1个阳性克隆,经序列测定,该基因与GenBank中已知基因无明显同源性,含有长度为609bp的开放阅读框,编码203个氨基酸,命名为Arta1;该重组变应原在大肠杆菌中高效表达为相对分子质量(Mr)为22.7×103蛋白,进一步在Ni2+亲和层析柱得到高度纯化;免疫学分析表明重组变应原有良好的IgE结合活性。结论本研究克隆和鉴定了一个青蒿花粉主要变应原Arta1(登录号为:CK700713),为花粉过敏性疾病的诊断和免疫治疗及进一步的实验研究奠定基础。  相似文献   

5.
重阳木花粉过敏原的分离、纯化和鉴定   总被引:1,自引:1,他引:0  
目的对重阳木花粉变应原蛋白进行分离、纯化和鉴定。方法采用Coca s液提取重阳木花粉的粗提液,通过十二烷基硫酸钠-聚丙烯酰胺凝胶电泳(SDS-PAGE)分离粗提液蛋白质组分,并测定其分子质量;收集过敏患者血清,用Western blot法鉴定其变应原成分;通过离子交换层析对重阳木花粉变应原进行初步纯化和免疫印迹鉴定。结果分离得到重阳木花粉18条蛋白带,其中分子质量为12和14 ku的是重阳木花粉的特异性变应原,通过离子交换柱层析方法纯化得到其相应的纯化蛋白。结论对重阳木花粉变应原进行了初步的分离、纯化和鉴定,为临床重阳木花粉过敏疾病的诊断和治疗奠定了基础。  相似文献   

6.
目的 对椰子花粉的变应原组分进行初步的分离、鉴定及纯化.方法 提取椰子花粉粗提液,用十二烷基硫酸钠.聚丙烯酰胺凝胶电泳(sDS-PAGE)分离椰子花粉的蛋白质组分并测定其相对分子质量,采用免疫印迹法鉴定其变应原成分,并通过离子交换层析对椰子花粉变应原进行初步分离纯化,免疫印迹进行检测.结果 SDS-PAGE显示椰子花粉粗提液有10条蛋白带,其中相对分子质量(肘,)为60 000、50 000、35 000、28 000、19 000、16 000和14 000的蛋白可与椰子花粉过敏性病人血清IgE结合,且M,50 000、16 000和14 000为主要变应原;离子交换层析结果显示主要过敏原成分主要分布在V峰中.结论 对椰子花粉变应原进行了初步的分离、鉴定和纯化,为临床椰子花粉变态反应疾病的诊断和治疗奠定了基础.  相似文献   

7.
目的对油菜花粉的变应原组分进行鉴定及初步的分离及纯化。方法提取油菜花粉粗提液,然后通过十二烷基硫酸钠-聚丙烯酰胺凝胶电泳(SDS-PAGE)分离油菜花粉的蛋白质组分并测定其相对分子质量,采用免疫印迹(Western blotting)法鉴定其变应原成分,并通过离子交换层析对油菜花粉变应原进行初步分离纯化,免疫印迹进行检测。结果油菜花粉粗提液有10余条蛋白带,其中相对分子质量为30 000、25 000、15 000和10 000的蛋白可与油菜花粉过敏性病人血清IgE结合,其中15 000和10 000为主要变应原;离子交换层析结果显示主要过敏原成分主要分布在Ⅰ、Ⅱ和Ⅲ峰中。结论对油菜花粉变应原进行了初步的分离、鉴定和纯化,为临床油菜花粉变态反应疾病的诊断和治疗奠定了基础。  相似文献   

8.
目的对短穗鱼尾葵花粉粗浸液的主要变应原进行分析、鉴定。方法通过SDS-PAGE分析短穗鱼尾葵花粉蛋白质组份,采用Western blotting鉴定主要变应原,以短穗鱼尾葵花粉粗浸液包板,摸索出其包被浓度、血清稀释度和酶结合物浓度,采用BSA-ELISA法对短穗鱼尾葵花粉过敏患者血清进行初步检测,并与皮肤挑刺试验比较。结果短穗鱼尾葵花粉粗浸液SDS-PAGE显示有30余条蛋白条带,其中主要蛋白条带有10条,Western blotting显示5例短穗鱼尾葵花粉过敏患者的混合血清能与其中3条蛋白条带起反应,分子量分别是26000、14000和12000Mr。BSA-ELISA检测短穗鱼尾葵花粉特异性IgE,最适粗浸液稀释度为1:100,血清稀释倍数为1:5,生物素化抗体为1:1000,辣根过氧化物酶标记的链霉亲和素(strepavidin-HRP)为1:1000。在此条件下BSA-ELISA与浸液皮试比较,检出结果与皮试阳性患者血清符合率为90%,与皮试阴性患者符合率为80%,与健康人对照检测符合率为100%。结论本实验对短穗鱼尾葵花粉主要变应原进行了分离和鉴定,BSA-ELISA法测定结果与皮肤挑刺试验初步比较符合率较好。  相似文献   

9.
目的 对粉尘螨(Dermatophagoides farinae)变应原进行分离和鉴定其特异性变应原组分. 方法 采用ELISA检测粉尘螨变应原的生物活性.按常规方法制备粉尘螨浸出液,经SDS-PAGE分离,测定各组分的相对分子质量(M,);同时用对螨过敏的60例病人混合血清(建立血清库)作探针进行Westem blot,鉴定其特异性变应原组分. 结果 SDS-PAGE显示粉尘螨有15条蛋白带,Mr在14×103-109×103之间,其中主带有9条,M,分别为109×103、100×103、86×103、62×103、56×103、36×103、28 x103、19×103、14×103;Western blot结果表明,浸出液中共有5条致敏条带,其M,分别为109×103、100×103、36×103、28 x 103、14×103;经ELISA检测粉尘螨浸出液具有生物活性. 结论 粉尘螨的特异性变应原有5条,分别为109×103、100×103、36×103、28×103、14×103,其浸出液有稳定的生物活性.该研究为开发适合我国人群的粉尘螨标准化试剂提供了试验依据.  相似文献   

10.
目的:表达、纯化和鉴定法国梧桐花粉主要变应原基因Platanus acerifolia pollen allergen1(Pla a1)。方法:首先根据文献查找并在GenBank获取法国梧桐花粉主要变应原基因序列Pla a1,利用DNAStar软件进行密码子优化;合成全基因;将Pla a1与载体pET-44a连接后转入大肠杆菌Rosetta中进行诱导并优化目的蛋白表达;利用亲和层析法纯化该外源表达蛋白;应用Western blot,利用法桐花粉过敏患者血清鉴定纯化后的目的蛋白的抗原性。结果:成功构建了pET44a-Pla a1阳性质粒;获得了法桐花粉主要变应原重组蛋白Pla a1;对该重组蛋白进行了亲和层析纯化;免疫印记法表明重组蛋白具有一定的抗原性。结论:首次利用密码子优化的方法获得融合Strep TagⅡ的法桐花粉过敏原重组蛋白Pla a1,为制备高纯度变应原、重组低致敏过敏原及变应原核酸疫苗奠定基础。  相似文献   

11.
BACKGROUND: Artemisia vulgaris is a widespread weed in the Mediterranean area and several allergens have been detected in its pollen. One of them, Art v 3, belongs to the lipid-transfer protein (LTP) family and its prevalence in Artemisia-sensitized patients or its relationship with other LTP allergens is not clear. OBJECTIVE: To assess the pattern of sensitization to an array of mugwort allergens in a Mediterranean population, and to study the cross-reactivity of Art v 3 with Pru p 3 and Par j 1, relevant LTP allergens in the area. METHODS: Skin prick test was performed with whole extracts (A. vulgaris, Parietaria judaica and peach) and pure natural allergens Art v 1, Art v 3, Art v 60 kDa and Par j 1 in 24 mugwort-allergic patients from a Mediterranean area. In vitro assays included measurement of specific IgE and ELISA inhibition among LTP allergens. RESULTS: The three Artemisia allergens elicited a positive skin response in 70-80% of the patients. Seven patients were clearly sensitized to Par j 1 and 11 to Pru p 3. There was no correlation between Par j 1 and Pru p 3 sensitization, but a highly significant correlation was found between peach extract and Art v 3 as regards the skin response. No IgE cross-reactivity was observed between Art v 3/Par j 1 or Pru p 3/Par j 1. In contrast, Art v 3 significantly inhibited the binding to Pru p 3 of IgE from three patients' sera out of six studied, but Pru p 3 was not able to inhibit the IgE binding to Art v 3. CONCLUSION: Art v 3 is a major mugwort allergen and in some patients with IgE to both Art v 3 and Pru p 3, Art v 3 behaves as the primary sensitizing agent.  相似文献   

12.
The pollen of Artemisia has been considered as the main late summer-autumn allergen source in this country. To identify its allergenic components, Artemisia princeps pollen extracts were separated by 10% sodium dodecylsulfate polyacrylamide gel electrophoresis (SDS-PAGE), and transferred to nitrocellulose membrane, where IgE binding components were detected by the reaction with sera of twenty Artemisia-allergic patients and 125I-anti-human IgE, sixteen components in the molecular range of 10,000 and 85,000 daltons were detected. Twelve bands bound to IgE from 50% of the sera tested, and two bands (37,000, 23,000 daltons) showed the highest (85%) frequency of IgE-binding in twenty sera tested. When the gel of SDS-PAGE with Artemisia pollen extracts was sliced into 11 allergenic groups (AG) and the protein of each AG was obtained by the gel elution method, the wormwool-RAST inhibition test showed that the AG 10 demonstrated to be the most potent, and the AG 7 was the next. Six AGs showed significant responses (more than 100% of wheal size to histamine, 1 mg/ml) on the skin prick test in more than 50% of the patients tested. It is suggested that electrophoretic transfer analysis with SDS-PAGE may be a valuable method for Artemisia allergen identification, and the possibility of partial purification of allergens by employing gel elution is discussed.  相似文献   

13.
BACKGROUND: Lipid-transfer proteins (LTPs), but not Bet v 1 homologues, have been identified as major allergens of apple and peach in the Rosaceae fruit-allergic population in the Mediterranean area. Many of these patients show cosensitization to mugwort pollen. LTPs have an ubiquitous distribution in tissues of many plant species, and have been proposed as a novel type of plant panallergens. OBJECTIVE: We sought to isolate LTPs from Artemisia pollen and from a plant food not belonging to the Rosaceae family, such as chestnut nut, and to compare their amino acid sequences and IgE-binding capacities with those of apple and peach LTPs. METHODS: Allergens (LTPs) were isolated by different chromatographic methods (gel-filtration, ion exchange and/or reverse-phase HPLC), and characterized by N-terminal amino acid sequencing and MALDI analysis. Specific IgE-quantification and immunodetection, as well as immunoblot and ELISA inhibition assays, were carried out using sera from patients allergic to both apple and peach. RESULTS: Purified LTPs from Artemisia pollen and from chestnut seed showed molecular masses about 9 700d, and 43-50% sequence identity with the equivalent allergens of apple and peach in the first 30 N-terminal residues, which comprise about one third of the total amino acid sequence. A similar degree of sequence identity (50%) was found between the Artemisia and chestnut proteins. Both isolated LTPs bound specific IgE of sera from Rosaceae fruits allergic patients. However, substantially lower values of specific IgE-binding and maximum ELISA inhibition percentages were obtained for Artemisia and chestnut LTPs when compared to those from apple and peach. CONCLUSION: LTPs from Artemisia pollen and chestnut crossreact with allergens (LTPs) of Rosaceae fruits, but significant differences in specific IgE-binding capacities were observed among members of the plant LTP family. Thus, further studies are needed to evaluate the clinical significance of the observed cross-reactivities of plant LTPs.  相似文献   

14.
Background An association between sensitization to Compositae pollens and hypersensitivity to hazelnut has been previously described. There is no previous in vitro study about crossreactivity between mugwort pollen and hazelnut. Objectives To study mugwort pollen and hazelnut allergens and to assess if there is IgE crossreactivity between mugwort pollen and hazelnut. Methods A serum pool formed by 28 individual sera with specific IgE to mugwort pollen and hazelnut was used to investigate IgE crossreactivity. RAST-inhibition, SDS-PAGE/IEF immunoblotting inhibition assays were performed by preineubation of the sera with mugwort pollen and hazelnut. Results RAST to hazelnut was inhibited up to 63% by mugwort pollen, but the mugwort pollen RAST was only inhibited up to 36% by hazelnut. In SDS-PAGE immunoblotting mugwort pollen showed nine allergens ranging from < 16 to 65kDa and hazelnut had four main allergens: 42kDa, 17kDa and < 16kDa (two bands). In the SDS-PAGE immunoblotting inhibition hazelnut partially inhibited all the mugwort pollen bands, except that with 19kDa, whereas mugwort pollen produced a nearly total inhibition of all the hazelnut allergens. In isoeleetrofocusing immunoblotting mugwort pollen had two groups of allergens: pI 7.5–8.5 and pi 3.5–5.2 and hazelnut one group of allergens: pI 5.2–5.8. In the isoeleetrofocusing immunoblotting inhibition hazelnut produced a partial inhibition of all the bands of mugwort pollen and mugwort pollen partially inhibited all the allergenic bands of hazelnut. Conclusions The RAST and SDS-PAGE/IEF immunoblotting inhibition results provide evidence of IgE cross reactivity between mugwort pollen and hazelnut allergens. The inhibition of hazelnut by mugwort pollen is higher than the inhibition of mugwort pollen by hazelnut in both RAST inhibition and SDS-PAGE immunoblotting inhibition. These results suggest that mugwort pollen allergens would behave as primary immunogens in the association between sensitivity to mugwort pollen and hazelnut.  相似文献   

15.
Background Beech and oak pollen are potential allergen sources with a world‐wide distribution. Objective We aimed to characterize the allergen profile of beech and oak pollen and to study cross‐reactivities with birch and grass pollen allergens. Methods Sera from tree pollen‐allergic patients with evidence for beech and oak pollen sensitization from Basel, Switzerland, (n=23) and sera from birch pollen‐allergic patients from Vienna, Austria, (n=26) were compared in immunoblot experiments for IgE reactivity to birch (Betula pendula syn. verrucosa), beech (Fagus sylvatica) and oak (Quercus alba) pollen allergens. Subsequently, beech and oak pollen allergens were characterized by IgE inhibition experiments with purified recombinant and natural allergens and with allergen‐specific antibody probes. Birch‐, beech‐ and oak pollen‐specific IgE levels were determined by ELISA. Results Beech and oak pollen contain allergens that cross‐react with the birch pollen allergens Bet v 1, Bet v 2 and Bet v 4 and with the berberine bridge enzyme‐like allergen Phl p 4 from timothy grass pollen. Sera from Swiss and Austrian patients exhibited similar IgE reactivity profiles to birch, beech and oak pollen extracts. IgE levels to beech and oak pollen allergens were lower than those to birch pollen allergens. Conclusion IgE reactivity to beech pollen is mainly due to cross‐reactivity with birch pollen allergens, and a Phl p 4‐like molecule represented another predominant IgE‐reactive structure in oak pollen. The characterization of beech and oak pollen allergens and their cross‐reactivity is important for the diagnosis and treatment of beech and oak pollen allergy.  相似文献   

16.
H. Ipsen    H. Formgren    H. Løswenstein  L. Ingemann 《Allergy》1985,40(4):289-294
A reference extract of mugwort pollen (Artemisia vulgaris) was characterized by crossed immunoelectrophoresis (CIE), crossed radio immunoelectrophoresis (CRIE) and quantitative skin prick test (QSPT). CIE revealed that the extract contained at least 42 distinct antigens of which 24 migrated towards the anode and 18 towards the cathode at pH 8.6. A CRIE analysis of the crude mugwort pollen extract, performed with sera from 29 mugwort-allergic patients, showed that 10 antigens may be considered allergens; one was classified as a major allergen, five as intermediate allergens, and four as minor allergens. The QSPT performed on the same 29 allergic patients established that 17.4 micrograms lyophilised reference mugwort pollen extract per ml had a biological potency of 1 HEP (histamine equivalent by prick test).  相似文献   

17.
BACKGROUND: Patients suffering from allergic rhinoconjunctivitis and dyspnoea during summer may exhibit these symptoms after contact with flowers or dietary products of the elderberry tree Sambucus nigra. OBJECTIVE: Patients with a history of summer hayfever were tested in a routine setting for sensitization to elderberry. Nine patients having allergic symptoms due to elderberry and specific sensitization were investigated in detail. We studied the responsible allergens in extracts from elderberry pollen, flowers and berries, and investigated cross-reactivity with allergens from birch, grass and mugwort. METHODS: Sera from patients were tested for IgE reactivity to elderberry proteins by one-dimensional (1D) and 2D electrophoresis/immunoblotting. Inhibition studies with defined allergens and elderberry-specific antibodies were used to evaluate cross-reactivity. The main elderberry allergen was purified by gel filtration and reversed-phase HPLC, and subjected to mass spectrometry. The in-gel-digested allergen was analysed by the MS/MS sequence analysis and peptide mapping. The N-terminal sequence of the predominant allergen was analysed. RESULTS: 0.6% of 3668 randomly tested patients showed positive skin prick test and/or RAST to elderberry. IgE in patients' sera detected a predominant allergen of 33.2 kDa in extracts from elderberry pollen, flowers and berries, with an isoelectric point at pH 7.0. Pre-incubation of sera with extracts from birch, mugwort or grass pollen rendered insignificant or no inhibition of IgE binding to blotted elderberry proteins. Specific mouse antisera reacted exclusively with proteins from elderberry. N-terminal sequence analysis, as well as MS/MS spectrometry of the purified elderberry allergen, indicated homology with ribosomal inactivating proteins (RIPs). CONCLUSION: We present evidence that the elderberry plant S. nigra harbours allergenic potency. Independent methodologies argue for a significant homology of the predominant 33.2 kDa elderberry allergen with homology to RIPs. We conclude that this protein is a candidate for a major elderberry allergen with designation Sam n 1.  相似文献   

18.
Purification of Art v I, a relevant allergen of Artemisia vulgaris pollen   总被引:2,自引:0,他引:2  
An allergenic protein from Artemisia vulgaris pollen has been purified to homogeneity. Its molecular weight in native conditions is 47,000. The purified allergen, hereafter denominated Art v I, is a monomeric protein. It is a clinically relevant allergen since, at least, 70% of the individuals allergic to Artemisia vulgaris pollen have specific IgE in serum and in mast cells, demonstrated by ELISA and skin prick tests, respectively.  相似文献   

19.
BACKGROUND: Pollinosis to Chenopodium album has been reported, but no data are available on its allergenic proteins. METHODS: An allergen from C. album pollen has been isolated by means of gel permeation and reverse-phase high-performance liquid chromatography. Molecular characterization was achieved by concanavalin A reaction, mass spectrometry, Edman degradation and cDNA sequence. Antigenic analyses were performed by immunoblotting, ELISA, and ELISA inhibition, using sera from allergic patients, two Ole e 1-specific monoclonal antibodies and an Ole e 1-specific polyclonal antiserum. RESULTS: The isolated allergen, Che a 1, is a glycoprotein of molecular mass 17.088 kD and 143 amino acid residues, whose sequence exhibits 27-45% identity with known members of the Ole e 1-like protein family. 77% of sera from patients allergic to chenopod pollen were reactive to Che a 1. No correlation was found between the IgE reactivities to Che a 1 and Ole e 1, the major allergens from olive pollen, and both allergens display low, although detectable, IgE and IgG cross-reactivities. CONCLUSIONS: Che a 1, a relevant allergen from chenopod pollen, is structurally related to the Ole e 1-like protein family, but exhibits significant differences on its polypeptide sequence that could explain its different antigenic behavior and limited cross-reactivity.  相似文献   

20.
BACKGROUND: Sera of patients allergic to olive (Olea europaea) pollen were used to analyze the IgE cross-reactivity between olive-pollen extract and other pollens obtained from phylogenetically unrelated species. METHODS: We used IgE immunostaining of pollen extracts blotted to nitrocellulose membranes after SDS-PAGE and inhibition analysis of this binding. RESULTS: A high inhibition of the IgE binding on olive-pollen extract was exhibited by birch, mugwort, pine, and cypress pollens, suggesting that these extracts contain proteins which share common epitopes and thus can be recognized by olive-allergic sera. IgE binding to Gramineae pollen extracts was not inhibited by olive-pollen extract, indicating a primary sensitization of the patients to these species. From the inhibition assays, the presence of an allergen of 45 kDa in the olive pollen, which has no homologous counterparts in other allergenic species, has been inferred. CONCLUSIONS: Olive pollen contains allergens which cross-react with pollens from unrelated species, a fact that could simplify the diagnosis and treatment of pollinosis.  相似文献   

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