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Puopolo M Ladogana A Almonti S Daude N Bevivino S Petraroli R Poleggi A Quanguo L Pocchiari M 《Journal of clinical epidemiology》2003,56(5):494-499
The objective was to identify any possible cases of variant Creutzfeldt-Jakob disease (CJD) in Italy, and to estimate the trends in mortality from sporadic CJD for 1993-2000. CJD cases were ascertained through direct notification to the Registry; 382 definite or probable sporadic CJD patients, but no cases of variant CJD were identified. The average yearly mortality rate was 1.04 cases per million inhabitants, with an increase in deaths in the 60-69 and > or =70 year age groups. Survival was shorter in male respect to female and in patients with an age at onset > or =65 years. CJD cases were uneven distributed among different regions in the period 1993-1995, but not herein after. The rise in mortality from sporadic CJD in Italy likely reflects increased awareness and better diagnosis during the years. However, continuous notification and postmortem examination of all suspected cases are recommended for optimal surveillance. 相似文献
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Gibson PR Rosella O Wilson AJ Mariadason JM Rickard K Byron K Barkla DH 《Carcinogenesis》1999,20(4):539-544
Butyrate may have paradoxical effects on epithelial cells of similar origin. This study aimed to examine the hypothesis that one mechanism that dictates a cell's response to butyrate is its state of activation. First, the responses to 24 h exposure to butyrate (1-2 mM) of normal and neoplastic human colonic epithelial cells activated by their isolation and primary culture, and of colon cancer cell lines, LIM1215 and Caco-2, were examined. In primary cultures of normal and cancer cells, butyrate had no effect on alkaline phosphatase activities but significantly suppressed urokinase receptor expression by a mean +/- SEM of 30 +/- 12% and 36 +/- 9%, respectively. Interleukin-8 secretion was suppressed by 44 +/- 7% in normal cells (P < 0.05) but was unchanged in cancer cells. In contrast, the cell lines significantly increased alkaline phosphatase activities by >50%, urokinase receptor expression >2-fold and interleukin-8 secretion >3-fold in response to butyrate. Secondly, the effect of butyrate on Caco-2 cells was examined with or without prior exposure to a specific activating stimulus [tumour necrosis factor alpha (TNF alpha)]. Interleukin-8 secretion increased by 145 +/- 23% and 132 +/- 17% on 24 h exposure to 2 mM butyrate or 0.1 microM TNF alpha alone, respectively. However, in cells pre-treated with TNF alpha, butyrate significantly inhibited secretion by 34 +/- 7% below unstimulated levels. The response to butyrate of urokinase receptor, whose expression was not stimulated by TNF alpha, was unchanged. These effects were mimicked by trichostatin A, an inhibitor of histone deacetylase, suggesting that butyrate's paradoxical effects may have been operating by the same mechanism. In conclusion, some of the paradoxical effects of butyrate do not appear to represent inherent differences between normal and transformed cells. Rather, the response may be determined by the state of activation of the cells. 相似文献
36.
Genetics of ABO, H, Lewis, X and Related Antigens 总被引:14,自引:0,他引:14
The present knowledge on chemical, enzymatic, serologic and genetic aspects of ABH antigens is reviewed in an effort to produce a simple and coherent genetic model for the biosynthesis of these antigens and chemically related structures. The genetic control of type 1 (Le(a), Le(b), Le(c) and Le(d)), type 2 (X, Y, I, and H), type 3 and type 4 ABH and related antigens in different animal and human tissues is analyzed, taking into account the properties of the glycosyltransferases which are involved in their synthesis and considering possible competition for common acceptor and donor substrates. The phylogeny of ABH determinants shows that they appeared as tissular antigens much earlier than as red cell antigens. The ontogeny of ABH antigens suggests that they behave as differentiation antigens, and an effort is made to correlate their tissular distribution in the adult with the embryological origin of each tissue. 相似文献
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E Tagliabue F Centis M Campiglio A Mastroianni S Martignone R Pellegrini P Casalini C Lanzi S Ménard M I Colnaghi 《International journal of cancer. Journal international du cancer》1991,47(6):933-937
In order to obtain further information on the biological role of the HER2/neu oncoprotein monoclonal antibodies (MAbs) were produced against the p185 extracellular domain. To immunize the mice and screen the hybridoma supernatants we selected a lung adenocarcinoma cell line (Calu-3), which demonstrated an over-expression of p185HER2 measured as the reactivity with polyclonal rabbit serum to the 14-amino-acid carboxy-terminal-HER2/neu. Two MAbs, designated MGR2 (IgG1) and MGR3 (IgG2), selected for reactivity on Calu-3 and negativity on A43I live cells, the reference target cell for EGF receptor expression, were found to immunoprecipitate a 185-kDa molecule. Immunodepletion experiments with the polyclonal antiserum and cross-competition experiments indicated that the 2 reagents recognized 2 different epitopes located on the p185HER2 molecule. One of the 2 MAbs, MGR3, was found to internalize, induce p185HER2 phosphorylation and inhibit tumor cell growth in vitro. These results indicate that MGR3 is directed against a determinant located in the p185HER2 ligand binding site and may compete with the p185HER2 ligand, but is incapable of inducing a complete mitotic signal. 相似文献
39.
M Andreani C Carcassi S Nesci M Manna F Centis G La Nasa M L Manca P Cornaglia-Ferraris S Orru G Lucarelli 《Haematologica》1991,76(4):285-288
BACKGROUND. In this work we investigated whether serologically HLA class II compatible donor-recipient pairs showed differences in restriction fragment length patterns, and whether there is a correlation between the genomic differences observed and the incidence of rejection and acute graft versus host disease (GVHD). METHODS. High molecular weight DNA was extracted from thirty-three transplanted thalassemic patients and from their genotypically HLA identical donors. The DNA was digested with TaqI and PstI restriction enzymes, separated by horizontal electrophoresis and transferred onto nylon filters. RESULTS. Differences at the molecular level were observed in only one patient, who rejected the transplant respect to his donor when DNA was digested with the TaqI restriction enzyme and hybridized with DPB cDNA probe. CONCLUSIONS. Although the molecular analysis revealed a difference between a patient who rejected the transplant and his donor, the RFLP typing confirmed the serological identity of the HLA class II antigens in all the other donor-recipient pairs studied. 相似文献
40.
Alberto Bartorelli Roberto Accinni Rosella Ferrara Carla Biancardi Giovanni Dragoni 《International Journal of Clinical & Laboratory Research》1976,6(1):79-84
Summary The two methods used to analyze 384 plasma samples were the carcinoembryonic antigen test (CRT) performed at the Roche laboratories
and the direct radioimmunoassay plasma carcinoembryonic antigen (DRPC) technique. The first test, which is quantitative, gave
many false positives below the 5 ng/ml level (also when used in a larger series of 4,628 subjects), thus invalidating its
use for detection of gastrointestinal neoplasms. The DRPC technique was positive in 62.3 % of 101 cases of gastrointestinal
adenocarcinoma and gave very few false positives. 相似文献