第四和五章：食品过敏及过敏原信息课件.ppt

1、lOVERVIEW OF FOOD ADEVERSE REACTION 食品不良反应的概述lSYMPTOMS OF ADVERSE FOOD REACTIONS食品过敏反应的症状lPREVALENCE发病率lFOOD ALLERGENS食品过敏原lFOOD ADDITIVES食品添加剂lA classical toxic food reaction is scombroid fish poisoning,due to large amounts of histamine 鲭亚目鱼组胺中毒是典型的动物食品毒性反应。豆类：四季豆、红腰豆、白腰豆。l毒素：植物血球凝集素，皂素，蛋白酶抑制剂，脂肪氧化

2、酶，抗维生素因子等l病发时间：进食后13小时内l症状：恶心呕吐、腹泻等。l研究发现，煮至80未全熟的豆类毒素反而更高，因此必须煮熟煮透煮变色后再吃。l毒素：生氰葡萄糖苷l病发时间：可在数分钟内出现。l症状：喉道收紧、恶心、呕吐、头痛等，严重者甚至死亡。食用时应将竹笋切成薄片，彻底煮熟。l笋含草酸，草酸很容易和钙、锌结合成草酸盐，会影响人体对钙和锌的吸收与利用。l苹果、杏、梨、樱桃、桃、梅子等水果的种子及果核l毒素：生氰葡萄糖苷（氰苷）l病发时间：可在数分钟内出现。l症状：与竹笋相同。此类水果的果肉都没有毒性，果核或种子却含有毒素，儿童最易受影响，吞下后可能中毒，给他们食用时最好去核。l毒素：秋

3、水仙碱l病发时间：一小时内出现。l症状：肠胃不适、腹痛、呕吐、腹泻等。秋水仙碱可破坏细胞核及细胞分裂的能力，令细胞死亡。经过食品厂加工处理的金针或干金针都无毒，如以新鲜金针入菜，则要彻底煮熟。l青色、发芽、腐烂的马铃薯l毒素：茄碱（龙葵素）l病发时间：一小时内出现。l症状：口腔有灼热感、胃痛、恶心、呕吐。l马铃薯发芽或腐烂时，茄碱含量会大大增加，带苦味，而大部分毒素正存在于青色的部分以及薯皮和薯皮下。茄碱进入体内，会干扰神经细胞之间的传递，并刺激肠胃道黏膜、引发肠胃出血。l毒素：银杏酸，银杏酚l症状：胃肠道症状，恐惧感，头痛，惊叫，抽搐，重者意识丧失。潜伏期112小时。l预防：生白果去壳，加水

4、煮熟或炒熟后再吃。熟白果也不能多吃。l有毒成分：毒蝇碱，蜡子树酸，鹿花蕈素，毒肽类等l症状：胃肠炎型，神经精神型，溶血型，脏器损害型生豆浆毒素：皂素；抗胰蛋白酶因子；植物血球凝集素等；l预防措施：文火维持煮沸5分钟；lenzymatic(resulting from an enzymatic defect,e.g.,lactase deficiency),“酶促性的”（因酶缺陷造成，如乳糖酶缺乏症）lpharmacological(depending on the direct effect of,e.g.,vaso-active amines naturally found in foods

5、)“药理学的”（取决于直接效应，如食品中天然存在的血管活性胺）l“Undefined不明确的”Clinical manifestations of IgE-mediated food allergy can remain localized at the site of the primary direct contact,i.e.,一直保持在最初的直接接触部位 the mouth 嘴throat(oral allergy syndrome)咽喉（口腔敏感综合症）the gastroiniesrinal tract(isolated gastrointestinal food allergy)

6、胃肠道（单独的胃肠道食品敏感症）Skin Respiratory tract GI tract Cardievascular S.皮肤 呼吸道 胃肠道 心脏血管系统45%25%20%10%以IgE为媒介的食品敏感综合症分布lAllergen:fresh foods(fruits and vegetables)过敏原：过敏原：新鲜食品（如水果和蔬菜）lSymptom 症状：症状：Itching of the lips,mouth,palate，throat 嘴唇、嘴、上腭咽喉等处立即发痒Hoarseness and/or swelling of the lips,tongue,uvula,and

7、 larynx 嗓音嘶哑，嘴唇、舌头、小舌、喉等肿胀lSymptom 症状：症状：1）The main symptoms of gastrointestinal food allergy are vomiting,nausea,diarrhea,and abdominal pains(colics or cramps).胃肠道主要症状:呕吐、反胃、腹泻以及腹部疼痛（绞痛或痛性痉挛）；2)Skin reactions include local or generalized pruritus,flush,urticaria,angioedema.morbilliform exanthema,an

8、d flare-up of atopic dermatitis 皮肤反应：局部的或无显著特点的搔痒症、面部潮红、风疹、血管性水肿、麻疹样疹病、突发特异性皮炎；3)The symptoms of the upper and the lower respiratory tract are rhinitis(sneezing,pruritus of the nose,nasal stuffiness,and nasal obstruction),larynx edema,cough,wheezing,and bronchial asthma.上呼吸道或稍低些的呼吸道症状：鼻炎（打喷嚏、鼻搔痒症、鼻子

9、不通气、鼻塞）、喉肿、咳嗽、喘息以及支气管哮喘；4)Itching,redness,and watering eyes(conjunctivitis)发痒、充血以及眼睛流泪（结膜炎）.lSymptom 症状：症状：respiratory symptoms 呼吸道综合症 lAllergen:flour,n-amylase,green coffee,castor and soy beans,spices.egg white,and crustaceans 过敏原：过敏原：面粉、-淀粉酶、绿咖啡、海狸香和大豆、调味品、鸡蛋白以及甲壳动物 lAllergen:fish,shrimp,flour,and

10、 pork 过敏原：过敏原：鱼、小虾、面粉和猪肉 lSymptom 症状：症状：Urticarial lesion 风疹lChronic contact with a food may induce protein contact,dermatitis in food handlers 食品操作工人长期接触某种食品会诱导蛋白接触性皮炎。DEFINITIONDEFINITION：The term Heiners syndrome characterizes a milk-induced syndrome with pulmonary disease in infants.Heiner综合症：婴儿

11、因牛奶诱导的肺病 lSymptom 症状：症状：chronic or recurrent pulmonary intiltrates chronic or recurrent pulmonary intiltrates 慢性或慢性或周期性发生的肺渗透周期性发生的肺渗透allergic alveolitis allergic alveolitis 过敏性齿槽炎过敏性齿槽炎a chronic rhinitis a chronic rhinitis 慢性鼻炎慢性鼻炎gastrointestinal blood loss gastrointestinal blood loss 肠胃失血症肠胃失血症ir

12、on deficiency anemia iron deficiency anemia 缺铁性贫血缺铁性贫血chronic cough chronic cough 慢性咳嗽慢性咳嗽recurrent fever recurrent fever 周期性发烧周期性发烧Anorexia Anorexia 厌食厌食Vomiting Vomiting 呕吐呕吐Colic Colic 绞痛绞痛Diarrhea Diarrhea 腹泻腹泻Hemoptysis Hemoptysis 咳血咳血lControl 控制措施：控制措施：linstitution of a milk-free diet饮食中去除牛奶lD

13、efinitionDefinition：damage to the small intestinal mucosa and symptoms of malabsorption定义：定义：小肠黏膜损伤和吸收不良症状lAllergen Allergen 过敏原：过敏原：Gliadin Gliadin 麦醇溶蛋白麦醇溶蛋白present in wheat,rye,barley,and oat present in wheat,rye,barley,and oat 广泛存在于小麦、燕麦、大麦和黑麦中广泛存在于小麦、燕麦、大麦和黑麦中 The peak incidence of symptoms is

14、in infancy after the introduction of cereals;婴儿开始添加谷物类食物时最容易发生这类症状，为第一高峰期；A second peak occurs during the third decade.第二高峰期发生在三十岁。lSymptom 症状：症状：labdominal pain周期性腹部疼痛lloose stools便溏lanorexia厌食lshort stature体态短小ldelayed puberty青春期滞缓lnutritional deficiencies吸收不良lDental enamel hypoplasia 牙科瓷发育不全lrecu

15、rrent aphthae周期性口疮 lControl 控制措施：控制措施：Patients with celiac disease must avoid gliadins and related proteins permanently远离麦醇溶蛋白以及相关蛋白质lDefinition 定义：chronic blistering disease 一种慢性起疱疾病 l Symptom 症状：症状：litchy 发痒lsometimes burning 有时有灼伤感leruption of grouped vesicles on an erythematous ground 在红斑状范围内出现成

16、群泡样出疹 lS o m e D H p a t i e n t s,e v e n w i t h o u t gastrointestinal symptoms,may have villous atrophy similar to that seen in celiac disease有些DH病人甚至在没有出现胃肠道综合症的情况下，也会出现与乳糜泻类似的绒毛状萎缩症，也就是说DH与CD之间有关连。lThe cutaneous manifestations may or may not respond to a gluten-free diet饮食中排除麦醇溶蛋白可能会、也有可能不会改善皮

17、肤症状。lDefinition Definition 定义：定义：elevated eosinophil counts in blood and tissue eosinophilia with release of eosinophii major basic protein 释放嗜曙红细胞主要基本蛋白质后，血液中嗜曙红细胞和嗜曙红血球增多的间质组织内嗜曙红细胞计数值升高 l Clinical manifestations 临床症状：临床症状：l vomiting 呕吐labdominal pain 腹部疼痛lDiarrhea 腹泻l malabsorption 吸收不良lbowel obs

18、truction 肠阻塞lAscites 腹水lThe cause of EG is unknown 起因还不清楚lfood hypersensitivity has been suggested EG可能由食品超敏性引起lDefinition 定义：an inflammatory bowel disease of unknown origin 一种不明起因的炎症性肠病 lNo adverse food reactions have been shown as causative of UC 还不能证明食品不良反应会造成UC lCause Cause 起因：起因：foods and food

19、additives 食品及其添加剂lSymptom Symptom 症状：症状：allergic purpura(widespread hemorrhagic macules and papules,mainly on the lower legs)demonstrated by single challenges变应性紫癜（分布广泛的出血性斑丘疹，主要出现在腿的下部）lDefinition 定义：定义：Lack of the enzyme that cleaves milk sugar,lactose,gives rise to adverse reactions when lactose

20、is consumed.当摄入乳糖时，由于体内缺乏一种能将牛奶糖质-乳糖水解的酶，从而产生不良反应 lThe only food of which lactose is a natural constituent is milk(3.7 g/100 ml cows milk).天 然 含 乳 糖 的 唯 一 食 品 是 牛 奶（3.7g/100ml牛奶）lClassification 分类：分类：1）congenital lactase deficiency先天性乳糖酶缺乏综合征2）primary lactase deficiency初级的乳糖酶缺乏综合征3）secondary lactase

21、 deficiency二级乳糖酶缺乏综合征 1）congenital lactase deficiency先天性乳糖酶缺乏综合征lactase is not present and symptoms will appear when the patient is breast-fed.人体内不存在乳糖酶，当进行人乳哺育时会出现综合征The congenital form is very rare 这种症状极少见2）primary lactase deficiency初级的乳糖酶缺乏综合征seen in most of the worlds population where the produc

22、tion of lactase decreases or disappears from the age of 2 to the teenage years在2-10岁时，乳糖酶分泌下降或消失l Persistent high lactase activity in adult life occurs among relatively few ethnic groups:成年人体内乳糖酶活性一直处于高峰的人群：lnorthern Europeans and their overseas descendants北欧以及沿海后代la few African groups of pastoral t

23、radition Bedouins and other Saudi Arabs一些源于牧人的非洲人、贝都因人和沙特阿拉伯人l certain groups from west India and Pakistan西印度和巴基斯坦部分人群l3）secondary lactase deficiency二级乳糖酶缺二级乳糖酶缺乏综合征乏综合征a consequence of pathological changes in the gut mucosa,as seen in celiac disease or inflammations.乳糜泻或炎症引起内脏黏膜病变的结果 When the gut m

24、ucosa has regained its normal appearance the lactase production reappears 当内脏黏膜恢复正常，乳糖酶也开始重新分泌。lThe symptoms The symptoms 症状：症状：Diarrhea 腹泻gas production 产气Colic 绞痛lControl 控制措施：avoid all products containing even small amounts of lactose 避免食用任何含乳糖的食品 lThe total prevalence of food allergy/food intole

25、rance is not known.总发病率未知lEstimates based on data from one country do not necessarily reflect the prevalence of another country 在某个国家统计得到的数据并不能用到另一个国家，因为：1）frequency and duration of breast feeding 母乳喂养的频率和持续时间2）eating habits饮食习惯3）flora植物群lallergy to cows milk,egg,and fish predominantly begins before

26、 the second year of age 对牛奶、鸡蛋和鱼的过敏性主要发生2岁以前lallergy to fruit,legumes,and vegetables predominantly begins after the second year.对水果、豆类和蔬菜的过敏性主要发生在2岁以后 lTable 1 Prevalence of Rhinitis and Oral Itch in Danish School Children 丹麦学龄儿童中鼻炎和口腔发痒的发病率丹麦学龄儿童中鼻炎和口腔发痒的发病率 Age(yr)Rhinitis(%)Oral itch（%)boys/girls

27、 boys/girls 5-7 9.0/5.7 0/0.38-10 8.5/7.1 0.8/1.111-13 14.0/8-5 1.9/1.514-16 17.3/13.0 2.9/2.0lAdverse reactions to food additives are found in 1-2%of school children 1-2%学龄儿童对食品添加剂有不良反应lThe prevalence in younger children is not known.至今不知小年龄儿童的发病率 lIn European studies the majority of allergic food

28、reactions in adults are caused by fruits.vegetables,and nuts and are related to pollen allergy 在欧洲，大部分成年人食品过敏性反应是由水果、蔬菜和坚果引起的，且与花粉过敏症有关lThe prevalence is around 5%发病率在5%左右lprobably only 0,5%have symptoms other than oral itch.大约只有0.5%不是口腔发痒症状lThe prevalence of allergy to milk,egg,fish.etc.is around 0

29、.2%，牛奶、鸡蛋、鱼等引起的过敏症发病率大约为0.2%lThe estimated frequency was 0.03-0.15%1982年EEC理论计算值：食品添加剂引起的发病率为0.03-0.15%lIn British：theprevalence 大不列颠人：发病率为0.026%lDutch 丹麦：0.4%l10%Danish women have contact allergy caused by nickel.10%丹麦妇女因镍造成接触性过敏症lUp to 10%of these may benefit from a nickel-restricted diet 其中10%以上会

30、因排除镍的饮食而改善lWhat is contact allergensWhat is contact allergens？In dermally sensitized subjects ingestion of the contact allergen may cause skin flare reactions or other symptoms,e.g.,in the gastroinlestinal tract 皮肤敏感症受检者摄入接触性过敏原后会导致皮肤潮间带反应或胃肠道症状等其他症状。lContact AllergensContact Allergens：fragrances 芳香

31、物质food flavors（natural or synthetic）食品风味物Nickel 镍 1）Celiac disease腹部疾病：Cause：wheat gliadin and related proteins起因：小麦麦醇溶蛋白和相关蛋白质The prevalence：0.2-0.5%发病率：0.2-0.5%2）lactase deficiency 乳糖酶缺乏综合征乳糖酶缺乏综合征Cause：Lack of lactase起因：缺乏乳糖酶起因：缺乏乳糖酶 The prevalence：varies from a few percent in northern European c

32、ountries to almost the entire adult population in Asia and Africa 发病率：发病率：从北欧国家到亚洲和非洲国家，从北欧国家到亚洲和非洲国家，成年人发病率相差好几个百分点成年人发病率相差好几个百分点 Conclusion：It is not known whether the prevalence of food allergy or intolerance is increasing 不清楚食品过敏/不耐性的发病率是否有上升趋势 The prevalence of pollen-related food allergies has

33、 increased.与花粉相关食品敏感症的发病率在提高。lAllergens are antigens that give rise to allergy.过敏原是能引起敏感的抗原lPollen花粉lMammals哺乳动物l mites螨lother insects其他昆虫l foods食品lComponent：过敏原成分：过敏原成分：Proteins or glycoproteins with a molecular weight from 3 to 90 kDa,the majority ranging from 10 to 40 kDa 已知结构的过敏原都是蛋白质或糖蛋白，分子量从3k

34、Da到90kDa，大部分在10kDa到40kDa之间lthe first three letters of the genus,space,the first letter of the species,space,and an Arabic number.l XXX X X 属 种 阿拉伯数字lFor example：Lol p 1 refers to the first pollen allergen identified from Lolium perennc,or rye grass Lol p 1表示第一个花粉过敏原，来自Lolium perenne 或黑麦草 majormajor：

35、proteins for which 50%or more of the allergic patients studied have specific IgE“主要的”：能使50%或以上被研究病人具有特异性IgE的蛋白质minorminor“：the remaining allergens are considered minor“次要的”：能使50%以下的被研究病人具有特异性IgE的蛋白质lTo make a complete list of allergenic foods on a global basis is virtually impossible.我们不可能列出一张食品过敏原清

36、单lWhether a food allergen causes significant problems in a population is dependent on several factors：某种食品过敏原是否会在消费者中引起明显的问题取决于以下几个方面：l some are much more frequent sensitizers lhan others有些抗体比其他抗体造成敏感症的次数更多，e.g.,-lactoglobulin in milk or ovomucoid from egg white如：牛奶中的-乳球蛋白或鸡蛋蛋白中的卵类粘蛋白1）The chemical

37、structure,i.e.,the amino acid sequence,and the tertiary structure 化学结构如氨基酸序列，蛋白质三级结构2）heat stability 热稳定性3）digestibility 可消化性4）Structural relationship with epitopes from nonfood allergens 非食品过敏原与抗原决定族之间的结构关系lIn Europe allergy to rice and buckwheat is uncommon.在欧洲，稻米和荞麦一般不引起敏感症lIn Japan rice and buck

38、wheat are common food allergens 在日本，稻米和荞麦通常是食品过敏原。1）aero-allergens：grasses,pollen of trees and herbs，house dust mites，o cat dander 飞散过敏原：草、树或药草的花粉、屋尘螨、猫毛发皮屑 2）work environment：baker工作环境：面包工人3）via the skin：Natural rubber(latex)通过皮肤：天然橡胶1)local species of grass,trees,and herbs and pollution 当地生长的草、树以及

39、药草种类e.g.,Allergy to hazelnuts is common in areas with many birch trees,where birch pollen hay lever is frequent榛实敏感症一般发生在有许多桦树的地区，在这些地区经常发生桦树花粉热2)air pollution空气污染lIn early infancy an increased uptake of antigen takes place at a time when the gut-associated lymphoid tissue is still incompletely deve

40、loped 在幼年早期，在与消化道相关淋巴组织还没有发育好的时候，抗原的摄入量相对较高。1）Albumin,-lactoglobulin,and immunoglobulins of milk are the most important allergens in infants婴儿：清蛋白、-乳球蛋白和免疫球蛋白2）In older children -lactoglobulin,caseins,and I-lactalbumin may be more reactive.大孩子：-乳球蛋白、酪蛋白和-乳白蛋白 3）in adulthood：casein to be the most fre

41、quent allergen 成人期：酪蛋白cross-reactions交叉反应交叉反应lThe majority of patients with allergy to cows milk proteins will also react to proteins from sheeps and goats milk 大部分对牛奶蛋白质有敏感症的病人同样对绵羊奶和山羊奶有敏感症 Cross-reactions between milk from these species is not always present.各种奶之间的交叉反应并不一直存在 l the second most fre

42、quent food allergen in small children after cows milk 在小孩子中大概是仅次于牛奶的食品过敏原 lEgg white proteins are reported to elicit allergic reactions more frequently than egg yolk.鸡蛋蛋白比蛋黄更易引起过敏反应Protein蛋白质Name分类名molecular weight 分子量(kDa)Content in egg white鸡蛋白中的含量(%)Ovomucoid(*key)卵类粘蛋白Gal d 12800011Ovalbumin 卵清蛋

43、白Gal d 24500054Ovotransferrin or conalbumin卵铁传递蛋白或伴清蛋白Gal d 37800012Lysozyme溶菌酶Gal d 4140003.4lcross-reactions交叉反应交叉反应:l allergy to egg can be correlated to allergy to bird feathers 鸡蛋敏感症与鸟类羽毛敏感症之间有相关性 lthe major cross-reacting determinants are the livetins from egg yolk.主要交叉反应的决定因素是蛋黄中的卵黄蛋白 lhazeln

44、ut 榛实lWalnut 胡桃lBrazil nut 巴西坚果lApple 苹果lAlmond 杏仁lPeach 桃子lPlum 李子lCherry 樱桃lPeanut 花生lPeas 豌豆lCarrot 胡萝卜lparsley 欧芹lCelery 芹菜lOrange 橘子lStrawberry 草莓lCereals 谷物1）the age of the patients 病人的年龄2）the methods of diagnosis 诊断方法以及3）the geographic location of the population 地理环境l More than 90%of patients

45、 with sensitization to vegetable foods had concomitant sensitization to pollen 90%以上的蔬菜敏感症总是伴随着花粉敏感症而来 lIn a group of birch pollen allergies the patients with additional hypersensitivity to nuts and apples had：l 在一组同时有另外的坚果和苹果超敏性的桦树花粉敏感症病人中 l(1)more severe symptoms during the pollen seasonl 在花粉季节症状严

46、重加重l(2)higher values of IgE to birch and hazel pollen,l 桦树和榛子花粉的IgE值较高l(3)a larger area of the skin prick test reactive to birch and hazel pollen compared to the group without apple and nut allergy l 与那些没有坚果和苹果超敏性病人相比，桦树和榛子花粉的皮肤穿刺试验反应区域要大得多。lThe symptoms The symptoms 主要症状：主要症状：lMainly from the mouth

47、 and pharynx,with itching,swelling of the lips,tongue,and throat.syndrome.从嘴到咽发痒，嘴唇、舌头以及咽喉肿胀lThese symptoms are called the“oral allergy”“口腔敏感综合症”lcross-reactions交叉反应交叉反应:1）A sensitization to mugwort pollens and different spices,the so-called mugwort-celery-spices syndrome,has been reported 艾蒿及其不同种艾属

48、植物的花粉有致敏性，又称艾蒿-芹菜-香料综合症。2）It was shown by prick,RAST studies,and RAST inhibition experiments 皮肤穿刺、RSAT研究以及RSAT抑制实验证明：a celery-thermolabile allergen seems to be involved in celery-birch-pollen-allergic patients 一种不耐热芹菜过敏原会导致芹菜-桦树-花粉敏感症 a thermostable allergen is involved in celery-mug wort-allergic p

49、atients.一种耐热过敏原会导致芹菜-艾蒿敏感症lPollen-related food allergies are thought to be caused by cross-reactions of pollen-specific IgE antibodies with epitopes of food proteins.花粉特异IgE抗体与食品蛋白质的抗原决定族发生交叉反应，导致了花粉相关食品敏感症 1）Bet v l is the major birch pollen allergen Bet v 1是主要的桦树花粉过敏原lAllergens with cross-reactivi

50、ty to Bet v 1：与Bet v 1有交叉反应的过敏原有：lApples 苹果lHazelnuts 榛实l cherries 樱桃lPears 梨子lCelery 艾蒿l carrots 胡萝卜2）Profilins are widely distributed in the plant kingdom and have been identified as plant pan Allergens.lProfilin广泛分布在植物王国，被称为“植物pan过敏原”l10 to 20%of the pollen-allergic patients are sensitized to pro