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41.
42.
AIM:To study the inflammatory bowel disease-5 locus(IBD5)and interleukin-23 receptor(IL23R)gene variants in UC patients and test for gene-gene interaction.METHODS:The study population(n=625)was comprised of 320 unrelated ulcerative colitis(UC)patients with Caucasian origin and 316 age-and gendermatched,healthy controls.Five variants in the IBD5 locus(IGR2198a1 rs11739135,IGR2096a1 rs12521868,IGR2230a1 rs17622208,SLC22A4 rs1050152 and SLC22A5 rs2631367)and two of the IL23R gene(rs1004819,rs2201841)were analysed.PCR and restriction fragment length polymorphism methods were used for genotyping,the SLC22A4 rs1050152 genotypes were determined by direct sequencing.Interactions and specific genotype combinations of the seven variants were tested by binary logistic regression analysis.The IL23R genotypes were stratified by IBD5 genotypes for further interaction analyses.RESULTS:For the IL23R rs1004819 A allele we found significantly higher allele frequency(P=0.032)in UC patients compared to control subjects.The SNP rs1004819 showed significant association with UC risk for carriers(P=0.004,OR=1.606;95%CI:1.160-2.223)and the SNP rs2201841 for homozygotes(P=0.030,OR=1.983;95%CI:1.069-3.678).Individually none of the IBD5 markers conferred risk to UC development.There was no evidence for statistical interaction either between IBD5 loci and IL23R genes using logistic regression analysis.After genotype stratification,we could detect a positive association on the background of rs1004819 A allele for SLC22A4 T,SLC22A5 C,IGR2198a1 C or IGR2096a1 T allele,the highest OR was calculated in the presence of SLC22A4T allele(P=0.005,OR=2.015;95%CI:1.230-3.300).There was no association with UC for any combinations of rs1004819 and IGR2230a1.The IL23R rs2201841homozygous genotype and IBD5 carrier status together did not confer susceptibility for UC.CONCLUSION:The present study has shown that UC susceptibility genes are likely to act in a complex interactive manner similar to CD.  相似文献   
43.
Composite endpoints are commonly used as the primary measure of efficacy in heart failure clinical trials to assess the overall treatment effect and to increase the efficiency of trials. Clinical trials still must enrol large numbers of patients to accrue a sufficient number of outcome events and have adequate power to draw conclusions about the efficacy and safety of new treatments for heart failure. Additionally, the societal and health system perspectives on heart failure have raised interest in ascertaining the effects of therapy on outcomes such as repeat hospitalization and the patient's burden of disease. Thus, novel methods for using composite endpoints in clinical trials (e.g. clinical status composite endpoints, recurrent event analyses) are being applied in current and planned trials. Endpoints that measure functional status or reflect the patient experience are important but used cautiously because heart failure treatments may improve function yet have adverse effects on mortality. This paper discusses the use of traditional and new composite endpoints, identifies qualities of robust composites, and outlines opportunities for future research.  相似文献   
44.
Summary.  A 398 bp fragment of the capsid protein (VP60) gene of 39 clinical samples of rabbit haemorrhagic disease virus (RHDV) and 17 of European brown hare syndrome virus (EBHSV), collected between 1981 and 1995 from 17 countries, was amplified by PCR and directly sequenced. The alignment of the nucleotide sequences and the subsequently constructed phylogenetic tree clearly separated RHDV from EBHSV as phylogenetic entities. The nucleotide homology rates between the RHDV and EBHSV groups ranged between 52.6% and 60.0%. The homology rates within the groups were much higher, 89.4% to 100% for the RHDV samples, and 89.4% to 100% for the EBHSV specimens. No intermediate viruses were found. Despite the high homology, three main branches could be identified in the phylogenetic tree of the RHDV samples, corresponding to the epizootiological data, while the EBHSV dendrogram did not show such well defined branches. The present results support the classification of RHDV and EBHSV as two distinct members of the Caliciviridae family. Nevertheless, a comparison with previously determined sequences of other caliciviruses shows that RHDV and EBHSV are more closely related to each other than to any other calicivirus. Received July 30, 1996 Accepted October 25, 1996  相似文献   
45.
Tuberculosis (TB) continues to be a major health problem due to lack of accurate, rapid, and cost-effective diagnostic tests. Serodiagnostic tests incorporating highly specific region of difference (RD) antigens (early secretory antigenic target 6 [ESAT-6], culture filtrate protein 10 [CFP-10], culture filtrate protein 21 [CFP-21], and mycobacterial protein from species tuberculosis 64 [MPT-64]) have recently been shown to be promising for specific diagnosis of TB in our lab. However, only few studies have reported the use of synthetic peptides of RD antigens, and none has used them to differentiate TB from sarcoidosis, a close mimic of smear-negative pulmonary TB (PTB) with entirely different management. The present study was conducted with an aim to study the utility of B-cell epitopes based peptides of RD1 (ESAT-6, CFP-10) and RD2 (CFP-21, MPT-64) antigens for immunodiagnosis of PTB for which sputum smear-positive PTB patients, sputum smear-negative PTB patients, sarcoidosis patients, and healthy controls (n = 24/group) were recruited. Bioinformatic software Bcepred was used to predict linear B-cell epitopes, using physico-chemical properties on a non-redundant dataset. Seven peptides as representative B-cell epitopes of ESAT-6, CFP-10, CFP-21, and MPT-64 were evaluated as targets of the antibody responses in TB patients and controls by enzyme-linked immunosorbent assay (ELISA). The current study showed sensitivity with individual peptides ranging from 37.5% to 83.3% for smear positive, 25% to 58.3% for smear negative as compared to 4.16% to 20.8% for sarcoidosis. Four out of 7 peptides that showed higher reactivity with TB patients and better discrimination from sarcoidosis patients representing ESAT-6, CFP-10, CFP-21, and MPT-64 were selected for multiepitope ELISA. The combination of peptides yielded 83.3% sensitivity for smear positive, 62.5% for smear negative, and only 4.16% for sarcoidosis. The specificity, however, for all the peptides/combination was 100%. Combination of peptides has proven to be better than individual peptides as per the latest criteria of the World Health Organization according to which a test that can replace smear microscopy with sensitivity of >90% for smear-positive patients and >65% for smear-negative TB patients with a specificity >95%, and thus, the present study suggests that a test based on combination of peptides selected from mycobacterial RD1 and RD2 antigens could be important for promoting an early diagnosis and management of otherwise difficult to diagnose smear-negative PTB patients. Moreover, it can also be used to discriminate sarcoidosis from PTB, thus preventing the misdiagnosis and mismanagement.  相似文献   
46.
Inhalation of foreign body into the tracheobronchial tree is a medical emergency sometimes resulting into sudden death. The current mortality rate due to foreign body inhalation ranges from 0% to 1.8%. Children with or without positive history of aspiration were examined and diagnosis was made on the basis of history, clinical findings, radiological evaluation and strong index of suspicion. A review of 30 cases of suspected foreign body aspiration revealed, children between 6 months were found to be very vulnerable to aspiration. Majority of children were boys. 80% of the patients had positive history of inhalation. Only 50% of the patients presented immediately i.e. within 24 hours after aspiration. Common symptoms were cough and respiratory distress. Decreased air entry was the significant clinical sign (50%). Obstructive emphysema and mediastinal shift were found in the majority of cases (50%). Rigid bronchoscopy under general anaesthesia and patient ventilating using a jet ventilator is a very safe and effective technique.  相似文献   
47.
The thymus provides an optimal cellular and humoral microenvironment for a cell line committed differentiation of haematopoietic stem cells. The immigration process requires the secretion of at least one peptide, called thymotaxin, by cells of the reticulo-epithelial (RE) network of the thymic stromal cellular microenvironment. The thymic RE cells are functionally specialised based on their intrathymic location and this differentiation is modulated by various interaction signals of differentiating Thymocytes and other nonlymphatic, haematopoietic stem cells. The subcapsular, endocrine, RE cell layer is comprised of cells filled with periodic acid Shiff's-positive granules, which also express A2B5/TE4 cell surface antigens and MHC Class I (HLA A, B, C) molecules. Thymic nurse cells also produce thymosins beta 3 and beta 4 and display a neuroendocrine cell specific immunophenotype (IP): Thy-1+, A2B5+, TT+, TE4+, UJ13/A+, UJ127.11+, UJ167.11+, UJ181.4+ and presence of common leukocyte antigen (CLA+). Cortical RE cells express a surface antigen, gp200-MR6, which plays a significant role of thymocyte differentiation. Medullar RE cells display MHC Class II (HLA-DP, HLA-DQ, HLA-DR) molecule restriction. Thymic RE cells also produce numerous cytokines that are important in various stages of haematopoietic cell activation and differentiation. The co-existence of pituitary hormone and neuropeptide secretion, as well as the production of a number of interleukins and growth factors, and expression of receptors for all, by RE cells is an unique molecular biological phenomenon. Thymic neuroendocrine polypeptides are the source of self antigens presented by the MHC molecules to differentiating haematopoietic stem cells. On the level of individual RE cells, the numerous projections associated with a single cell, which engulf developing lymphocytes, nurturing and guiding them in their maturation, may differ in their hormone production and/or hormone receptor expression profile, thus allowing a single cell to be involved in distinct, separate steps of the T-cell and other haematopoietic cell maturation process. Thymic RE cells represent an important cellular and humoural network within the thymic microenvironment and are involved in the homeopathic regulation mechanisms of the multicellular organism. The intrathymic T-lymphocyte selection is a complex, multistep process, influenced by several functionally specialised RE cells and under immuno-neuroendocrine regulation control reflecting the dynamic changes of the mammalian organism.  相似文献   
48.
Strictureplasty for obstructive Crohn's disease is still controversial because lesions are left in place and the suture is performed on a diseased bowel. Many surgeons prefer to perform bowel resection, hoping for fewer complications and a lower recurrence rate. In this paper, the authors reports their strictureplasty experience. They performed a systematic retrospective review of the patients suffering from Crohn's disease who underwent strictureplasties during a 10-year period in the abdominal surgery department of the University Hospital of Liège Sart Tilman, and studied the short- and long-term clinical results of 68 strictureplasties performed in 18 patients. Median follow-up was 63 months (range 12 to 144). Mortality was 0% and septic morbidity was 11% (one wound abscess and one leakage). Among the 16 patients available for the latest follow-up, symptomatic stenotic recurrence had to be medically treated in hospital for 4 patients (25%) with a recurrence delay range of 19 to 49 months. Stenosis recurrence needed re-intervention in one patient 48 months after surgery: stenosis occurred at a distance from the corrected site. These results confirmed that strictureplasty is a safe and efficient procedure in selected patients undergoing surgery for obstructive Crohn's disease.  相似文献   
49.
The survey was undertaken by ESWI in order to investigate the comparability of the laboratory diagnostic methods and the influenza surveillance systems used in 24 European countries. The results indicate considerable consensus in the general approaches to collection and use of clinical specimens, rapid diagnostic techniques, virus isolation techniques in eggs or/and MDCK cell lines, virus identification and use of inhibition of hemagglutination (IHA) and complement fixation (CF) tests for serological diagnostics. However, the details of the techniques used are somewhat heterogeneous: antigen detection methods (immunofluorescence versus immuno adsorbent assay), isolation methods (eggs versus tissue culture), reagents (locally produced, WHO, commercial) are not always equivalent and results are therefore not really comparable. Some of these discrepancies are due to a lack of resources or a lack of priority for influenza in the country. The greatest differences between individual countries exist in the epidemiological part of surveillance programmes. The mode of collection of influenza related mortality and absentism from work varies considerably in different countries. These findings indicate the need to harmonize viral procedures and surveillance systems in European countries in order to improve validity and comparability of results and as a prerequisite for early information on influenza etiology and spread.  相似文献   
50.
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