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991.
Genetic analysis of the CD28/CTLA4/ICOS (CELIAC3) region in coeliac disease   总被引:2,自引:0,他引:2  
Abstract:  In order to extend our previous findings of genetic linkage to the CD28/CTLA4/ICOS region on chromosome 2q33 ( CELIAC3 ) in coeliac disease (CD), we have investigated 22 genetic markers in 325 Norwegian/Swedish multiplex and simplex CD families. We found both linkage and association with several markers, primarily in the multiplex material. We observed strong linkage disequilibrium (LD) between SNPs (Single Nucleotide Polymorphisms) within an LD block delimited by MH30 and D2S72. A haplotype of this region marked by the alleles −1147*T: + 49*A:CT60*G:CT61*A was significantly associated with CD, suggesting that one or more polymorphisms of this haplotype, possibly −1147*T, are involved in CD susceptibility. The CT60 SNP, a polymorphism found to be most strongly associated with some other immune-mediated diseases, was not associated with CD, as this SNP was part of both associated and non-associated haplotypes. Moreover, our results suggest that CELIAC3 harbours several independent loci contributing to CD susceptibility.  相似文献   
992.
993.
Zusammenfassung Die vorliegende Arbeit gibt eine übersicht über onkozyt?re Metaplasien- und Neoplasien. Dabei werden insbesondere biochemische, zytochemische und molekulargenetische Ergebnisse er?rtert. Bekannt ist, da? in onkozyt?ren Zellen der Nebenschilddrüse sowie auch der Leber bei Zirrhose verst?rkt Defekte der Atmungskette vorkommen. Die zugrundeliegenden molekulargenetischen Mechanismen sind jedoch noch ungekl?rt. Es ist anzunehmen, da? sich onkozyt?re Metaplasien pathogenetisch von onkozyt?ren Neoplasien unterscheiden. Zudem bestehen organabh?ngige Unterschiede in der Prognose onkozyt?rer Neoplasien. Beispielsweise kommen onkozyt?re Karzinome bevorzugt in der Schilddrüse vor, w?hrend sie in anderen Organen vergleichsweise selten sind. Welche molekulargenetischen Mechanismen hierfür verantwortlich sind, ist noch weitgehend unbekannt.   相似文献   
994.
Regional cerebral blood flow was measured with positron emission tomography (PET) in six healthy volunteers at rest and during experimentally induced, sustained cutaneous pain on the dorsum of the right hand or on the dorsum of the right foot. Pain was inflicted by intracutaneous injection of capsaicin, providing a mainly C-fibre nociceptive stimulus. Statistical analysis showed significant activations along the central sulcus (SI) area when comparing pain in the hand to pain in the foot. Separate comparison of both pain states to a baseline revealed different locations along the central sulcus for hand pain and foot pain. The encountered differences are consistent with what is previously known about the somatotopics of non-painful stimuli. When comparing painful stimuli to baseline, the contralateral anterior cingulate gyrus, the ipsilateral anterior insular cortex and the ipsilateral prefrontal cortex were implicated. The results are consistent with an involvement of SI in the spatial discrimination of acute cutaneous pain. Received: 17 October 1996 / Accepted: 12 May 1997  相似文献   
995.
A new paradigm for the treatment of ulcerative colitis has recently been presented: Treatment of the mucosa with lidocaine (2%) enemas for prolonged periods. This therapy was introduced based on the hypothesis that hyperreactive autonomic nerves may play a pathogenetic role in the disease. One hundred consecutive patients have now been treated and the results presented. Theproctitis patients all responded to the treatment, despite previous therapeutic failures in more than two-thirds of the cases. They were treated for 3–12 weeks, but 68% had a relapse (observation period 20 months). Of the 49 patients withproctosigmoiditis, two-thirds had chronic symptoms resistant to previous therapy. One of these patients did not respond to lidocaine, but developed fulminant total colitis. The other patient had therapeutic failure with lidocaine but responded well to subsequent cortisone enemas. The patients were treated until the subsets of T-lymphocytes ( and ) disappeared from the mucosa. This occurred in parallel with symptomatic relief and eventual healing in 83% of the patients after treatment for 6–34 weeks. Of all the patients with proctosigmoiditis, 42% presented with recurrent symptoms (observation period 16 months). Of the 17 patients withleft-sided colitis, all went primarily into remission within 2–4 months, but 23% had a relapse (observation period 13 months). The 6 patients withtotal colitis had symptomatic relief and improvement of histology when treated over 3–8 months. One patient had recurrence after 12 months. Treatment with a local anaesthetic in ulcerative colitis is a new approach to mucosal inflammation. The beneficial effects may be due to blockade of certain neural effects, such as epithelial proliferation and shedding and congestion of the mucosal vasculature, with actions on cells of the immune system.This work was supported by grants from the Swedish MRC (2207, 5520), the Assar Gabrielsson Foundation, and the Ulf Widengren Foundation.  相似文献   
996.
Skin deposits in hereditary cystatin C amyloidosis   总被引:3,自引:0,他引:3  
Summary Clinically normal skin from 47 individuals aged 9–70 years was investigated. Cystatin C amyloid deposits were found in various locations of the skin by light and/or electron microscopy, in all 12 patients with a clinical history of hereditary cystatin C amyloidosis (HCCA). Six asymptomatic individuals, who had the Alu 1 restriction fragment length polymorphism (RFLP) marker reported to cosegregate with the disease, also had cystatin C amyloid deposits in the skin. Three asymptomatic individuals (age 17–46) belonging to the HCCA families were without amyloid in the skin but had Alu 1 RFLP marker. Skin from 12 individuals who served as controls and skin from 14 close relatives of the patients was negative for amyloid. Punch biopsy of the skin is a simple procedure which is of value for the diagnosis of HCCA, even before the appearance of clinical symptoms. This method might also be of use in following progression of the disease.  相似文献   
997.
Myeloperoxidase in human lung lavage   总被引:2,自引:0,他引:2  
Bronchial wash and bronchoalveolar lavage were performed in 12 healthy subjects (five smokers), in order to elucidate whether or not material of neutrophil origin may be phagocytized by lung macrophages in vivo. Cells from different levels in the bronchial tree were obtained by sequential injection and subsequent aspiration of either four 50-ml or five 10-ml aliquots. Each aliquot was used for the determination of total and differential cell counts. The proportion of myeloperoxidase-positive alveolar macrophages was determined by specific immune histochemical staining. The percentage of myeloperoxidase-positive macrophages was highest (median 94.8%, range 37-98.5%) in the 10-ml aliquots and lowest in the last three 50-ml aliquots (median values 1-2.5%) (P less than 0.001). A significant correlation was obtained between the fraction of myeloperoxidase-positive macrophages and the percentage count of bronchoalveolar lavage neutrophils (r = 0.466, P less than 0.05). Furthermore, the cellular myeloperoxidase showed a significant inverse correlation (r = -0.46, P less than 0.05) to the viability of the bronchoalveolar lavage cells. Our findings are compatible with previous demonstrations in animals of neutrophil phagocytosis by lung macrophages and show that this phenomenon in particular occurs in the more proximal airways. The internalization of neutrophils or neutrophil components by airway macrophages may be an important scavenger mechanism for protection of the lung from the deleterious effects of activated neutrophils.  相似文献   
998.
Intraductal papillary growth of mucin producting hypersecreting, columnar cells characterizes a group of rare pancreatic exocrine neoplasms which we propose to call intraductal papillary-mucinous tumors (IPMT). We analysed the histopathology of 26 IPMT in relation to gastro-enteropancreatic marker expression, genetic changes and biology. Four IPMT showing only mild dysplasia were considered to be adenomas. Nine tumours displayed moderate dysplasia and were regarded as borderline. Severe dysplasia-carcinoma in situ changes were found in 13 IPMT which were therefore classified as intraductal carcinomas. Six of these carcinomas were frankly invasive and two of these had lymph node metastases. The invasive component resembled mucinous noncystic carcinoma in all but one tumour which showed a ductal invasion pattern. Immunohistochemically, an intestinal marker type was found in most carcinomas, while gastric type differentiation prevailed among adenomas or borderline tumours. K-ras mutations (seven at codon 12 and one at codon 13) were found in 31% of IPMT (2 adenomas, 1 borderline, 5 carcinomas). Nuclear p53 overexpression was detected in 31% of IPMT (6 carcinomas and 2 borderline IPMT) and correlated with p53 mutations (one at exon 8 and the other at exon 5) in two carcinomas. p53 abnormalities were unrelated to K-ras mutation. c-erbB-2 overexpression was observed in 65% of IPMT, with various grades of dysplasia. Twenty-two of 24 patients are alive and well after a mean post-operative follow-up of 41 months. Only two patients, both with invasive cancer at the time of surgery, died of tumour disease. It is concluded that pancreatic IPMT encompass neoplasms which, in general, have a favorable prognosis, but are heterogeneous in regard to grade of dysplasia and marker expression. Adenoma, borderline tumour, intraductal carcinoma and invasive carcinoma can be differentiated. p53 changes but not K-ras mutation or c-erbB-2 overexpression are related to the grade of malignancy. Most IPMT differ in histological structure, marker expression and behaviour from ductal adenocarcinoma.  相似文献   
999.
Weber  B. H. F.  Stöhr  H.  Siedlaczck  I.  Longmire  J. L.  Deaven  L. L.  Duncan  A. M. V.  Riess  O. 《Chromosome research》1994,2(3):201-207
A cosmid library specific for human chromosome 11 has been constructed from flow-sorted chromosomes. The flow-purified chromosomes were prepared from the hamster/human hybrid line J1 which contains chromosome 11 as the only human chromosome. Individual clones were sampled in 187 microtitre plates, resulting in a total of 17 952 colonies. Hybridization analysis revealed that 83.7% of these clones were of human and 10.4% of hamster origin. The average insert size was estimated at 33.6 kb, and only 2.4% of insert fragments appear to be rearranged. This should result in 494 487 kb of cloned human DNA representing 3.5 chromosome 11 equivalents. We have prepared high-density nylon membranes of the arrayed library containing 1 536 single colonies per filter. We have demonstrated the usefulness of the library in the molecular genetic analysis of human chromosome 11 by testing for the presence of possibly polymorphic simple repeat motifs, by identifying cosmids that contain inserts from the telomeric ends of chromosome 11 and by assessing the potential of the library for rapid chromosome walking.  相似文献   
1000.
Summary Immunotherapy using bacille Calmette-Guérin (BCG) has gained increasing acceptance in the management of superficial bladder cancer. Systemic reactions after intravesical instillation of BCG are rare. However, when the therapy is complicated, the lung often becomes involved. Since the pathogenesis of lung infiltrates after immunotherapy is unknown, we report on a patient who developed a lung infiltrate after receiving BCG immunotherapy for bladder cancer. The infectious etiology was established by culture confirmation of a BCG strain in the broncheoalveolar lavage fluid.Abbreviation BCG bacille Calmette-Guérin  相似文献   
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