血吸虫病和激动的肠炎的诊断和流行病学的Toolszjr.pptx

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1、The Association of Schistosomiasis and Inflammatory Bowel Disease with Colorectal Cancer:Tools for Diagnosis and EpidemiologyPeter Chun,Ph.D In Egypt,schistosomiasis(from S.haematobium and mansoni)has been strongly linked to bladder cancer.The evidence includes:n nEpidemiological evidencen nExperime

2、ntally induced schistosomiasisn nHistopathology n nAge and gender ratios M.H.Mostafa et al.Relationship between Schistosomiasis and Bladder Cancer.Clin Microbiol Rev 1999.12(1)97-111The evidence linking S.manosini&haematobium infection to cancer of the large intestine is scant,but intestinal infesta

3、tion with S.japonicum is considered a significant contributory factor to the development of cancer of the colon and rectum.A.Ishii et al.Parasitic infection and cancer:with special emphasis on Schistosoma japonicum infections(Trematoda).A review.Mutat Res.1994 305(2)273-81n nColorectal cancer correl

4、ates with prevalence and intensity Colorectal cancer correlates with prevalence and intensity of shistosome infection.of shistosome infection.n nThe age of onset of cancer is lower in areas of shcistosome The age of onset of cancer is lower in areas of shcistosome endemicity and length of survival i

5、s shorter.endemicity and length of survival is shorter.n nAffected individuals usually have a long history of Affected individuals usually have a long history of inflammatory large bowel symptoms.inflammatory large bowel symptoms.n nThe cancers correspond in anatomic location to the area The cancers

6、 correspond in anatomic location to the area most affected by the parasite.most affected by the parasite.Z.Xu et at.Schsitosoma japonicum and colorectal cancer:an epidemiological study in the Peoples Republic of China.Int J Cancer.1984.34(3):315-8C.Ming-Chai et al.Evolution of colorectal cancer in s

7、chistosomiasis:transitional mucosal changes adjacent to large intestinal carconoma in colectomy specimens Cancer 1980.46(7):1661-75Chen et al.Colorectal cancer and schistosomiasis.Lancet 1981 971-3ES.Zhao et al.Carconoma of the large instestine with schistosomiasisanalysis of 279 cases.Zhonghua Zhon

8、g Liu Za Zhi.1981 3(1):67-9ES Zhao.Cancer of the colon and schistosomiasis.J R Soc Med.1981 74(9):645K.Shindo.Significance of schistosomiasis japonica in the development of cancer of the large intestine.Dis Colon Rectum 1976;(19)460-9K.Inoguchi et al.The correlation between primary colorectal carcin

9、oma and schistosomiasis japonica.Igakku Kenkyu 1978;(48)93-9K.Matsuda et al.Possible Associations of Rectal Carcinoma with Schistosoma japonicum Infection and Membranous Nephropathy:a Case Report with a Review.Japanese J Clin Oncol(29)576-581 Pathologically,patients with colonic schistosomiasis mani

10、fest epithelial dysplasia,and resemble the changes found in long-standing chronic ulcerative colitis.Chen et al.considered these dysplastic changes as premalignant lesions.Chen et al.Colorectal cancer and schistosomiasis.Lancet 1981 971-3The evidence associating colorectal cancer and ulcerative coli

11、tis and Crohns disease is strong.Tumors often occur at the site of chronic inflammation.The absolute risk of developing colorectal hanker is high when extensive disease begins at a young age.40%of patients diagnosed with pancolitis from ulcerative colitis before age 15 years developed colon cancer d

12、uring 20 years of follow up in a population-based linkage study in Sweden.DK Podolsky.Inflammatory bowel disease.N Engl J Med.2002.347:417-429S.japonicum lays a very large number of egg,and represents a constant source of irritation.Inflammation involves a series of host reponses that is designed to

13、 promote healing and tissue regeneration.These include recruiting specific types of cells,release of mediators and interactions of chemokines with various targets that affect cytological changes.Leukocytes generate reactive oxygen and nitrogen radicals which can damage proteins,membranes and DNA(inc

14、luding the genes controlling cell growth&proliferation).Inflammatory cells also release factors that inhibit apoptosis,induce angiogenesis,and impair certain immune responses.Collectively,these factors can accelerate mutagenesis,promote the survival and clonal proliferation of mutated cells,some of

15、which may become invasive and metastatic.M.Thun et al.Inflammation and cancer:an epidemiological perspecitive.In 2004 Cancer and Inflammation.Wiley,Chichester(Novartis Foundation Symposium 256).P6-28.We describe here two membrane based colloidal gold tests which can aid in the detection of inflammat

16、ory bowel disease and schistosomiasis.Both are easy to perform and can be done at the clinic level at the same time that other screening tests for colorectal cancer are done.We propose the use of these new tests to secure large scale epidemiological evidence linking these two diseases to colorectal

17、cancer in ChinaTests for Fecal Occult BloodChemical TestsChemical Testsn nPrinciple:Based on Principle:Based on peroxidase activity of peroxidase activity of heme.heme.n nAdvantages:Sensitive,Advantages:Sensitive,Inexpensive.Will detect Inexpensive.Will detect digested blood.digested blood.Quantitat

18、ion possible.Quantitation possible.n nDisadvantages:Not Disadvantages:Not specific.Dietary specific.Dietary restriction required.restriction required.Immunological TestsImmunological Testsn nPrinciple:Based on Principle:Based on detection of human detection of human hemoglobin.hemoglobin.n nAdvantag

19、es:Very specific.Advantages:Very specific.No dietary restrictions.No dietary restrictions.n nDisadvantages:Disadvantages:Expensive.More complex Expensive.More complex to perfom.to perfom.Examples of Chemical Testsn nChromogens:O-tolidine/Benzidine,Guaic,Chromogens:O-tolidine/Benzidine,Guaic,Pyramido

20、n.Pyramidon.Example of Immunological TestA comparison was made among four neutrophil-derived proteins in A comparison was made among four neutrophil-derived proteins in stool as an indicator of disease activity in ulcerative colitis.stool as an indicator of disease activity in ulcerative colitis.The

21、re is a need for a rapid test for lactoferrin.n nAn immunochromatographic test using polyclonal antibodies:a sandwich immunoassay with colloidal gold as visualization reagent.Instruments which allow for quantitationInstruments which allow for quantitationFlow through membrane test for detecting S.ja

22、ponicum antibodiesTTest spotAntigenControl spotProtein ACTest Procedure1.Wet membrane2.Add serumFlow through membrane test for detecting S.japonicum antibodiesTC*Specific anti-S.japonicum antibodies are captured on the antigen test spot.*Serum antibodies are nonspecifically captured on Protein A con

23、trol spot via its Fc region.0YYFcFlow through membrane test for detecting S.japonicum antibodiesTC 3.Wash 4.Add Protein-A Gold 5.WashYYFcAARed spot on T indicates a positive result.Absence of red spot indicates negative.Red spot on C indicates correct procedure.Absence indicates wrong procedure.YY=Serum antibody(nonspecific)=Specific anti-S.japonicum antibodyProcedure continuedThank you The staff of MedTrend Diagnostic Forumfrom