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21.
cagA-Positive Helicobacter pylori Populations in China and The Netherlands Are Distinct 总被引:9,自引:0,他引:9
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Arie van der Ende Zhi-Jun Pan Aldert Bart Ren W. M. van der Hulst Monique Feller Shu-Dong Xiao Guido N. J. Tytgat Jacob Dankert 《Infection and immunity》1998,66(5):1822-1826
The aim of this research was to study whether and to what extent Chinese cagA-positive Helicobacter pylori isolates differ from those in The Netherlands. Analysis of random amplified polymorphic DNA (RAPD)-PCR-assessed DNA fingerprints of chromosomal DNA of 24 cagA-positive H. pylori isolates from Dutch (n = 12) and Chinese (n = 10) patients yielded the absence of clustering. Based on comparison of the sequence of a 243-nucleotide part of cagA, the Dutch (group I) and Chinese (group II) H. pylori isolates formed two separate branches with high confidence limits in the phylogenetic tree. These two clusters were not observed when the sequence of a 240-bp part of glmM was used in the comparison. The number of nonsynonymous substitutions was much higher in cagA than in glmM, indicating positive selection. The average levels of divergence of cagA at the nucleotide and protein levels between group I and II isolates were found to be high, 13.3 and 17.9%, respectively. Possibly, the pathogenicity island (PAI) that has been integrated into the chromosome of the ancestor of H. pylori now circulating in China contained a different cagA than the PAI that has been integrated into the chromosome of the ancestor of H. pylori now circulating in The Netherlands. We conclude that in China and The Netherlands, two distinct cagA-positive H. pylori populations are circulating. 相似文献
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George J Barshack I Keren P Gazit A Levitzki A Keren G Roth A 《Experimental and molecular pathology》2005,78(3):233-238
BACKGROUND: Inflammation has been shown to play an important role in promoting the response to arterial injury and proinflammatory cytokines, such as tumor necrosis factor (TNF) alpha, are candidate mediators. AG-556 is a tyrosine kinase inhibitor proven to be effective in a model of multiple sclerosis-like syndrome in mice due to its immunomodulating effect. In the current study, we investigated the effect of the tyrphostin AG-556 on neointimal thickening and cytokine profile in a model of arterial injury in the mouse. METHODS: Injury was induced by external cuff placement on the left femoral artery of wild-type C57BL/6 mice. AG-556 dissolved in DMSO was injected intraperitoneally daily to the injured mice in a dosage of 2 mg/mouse. Control mice received DMSO injections. Histological analysis was carried out to assess neointimal formation. Splenocytes were cultured in the absence and presence of a mitogen for evaluation of thymidine incorporation and cytokine production. RESULTS: AG-556 treatment significantly attenuated intimal thickening (43,000+/-17,000 microm2; n=11) when compared to DMSO administration (286,000+/-127,000 microm2; n=10; P<0.05). Basal interferon-gamma production by splenocytes from AG-556-treated mice was increased by approximately 20-fold in comparison with levels in DMSO-treated animals, whereas Con-A induced secretion of the cytokine was similar between both groups. Levels of TNF-alpha, IL-4 and IL-10 in the culture supernatant from treated and non-treated animals did not differ significantly. CONCLUSION: The tyrosine kinase inhibitor AG-556 may have a role in the reduction of intimal thickening. The effect could be mediated via an immune modulating effect involving a significant increase in the smooth muscle cell inhibitory cytokine IFN-gamma. 相似文献
24.
van Galen JC Dukers DF Giroth C Sewalt RG Otte AP Meijer CJ Raaphorst FM 《European journal of immunology》2004,34(7):1870-1881
Polycomb group (PcG) genes encode two chromatin-binding protein complexes, the PRC1 and the PRC2 PcG complexes, which are essential for the maintenance of cell identity and play a role in oncogenesis. PcG complexes were recently identified as novel regulators of hematopoiesis, and appear to be expressed in a non-overlapping pattern in resting and mature follicular B cells. Using highly specific antisera in combination with immunohistochemistry and triple immunofluorescence, we investigated the expression pattern of nine human PcG genes in germinal center (GC) B cells and highly purified germinal center B cell subpopulations. PcG proteins were detected in characteristic binding patterns that were not necessarily related to mutually exclusive expression of the two PcG complexes. We conclude that the two PcG complexes are expressed throughout GC development, and that the fine composition of each complex is determined by the differentiation status of the cell. In addition, a subset of dividing cells with a centrocyte CD marker profile was identified that co-expresses core components of the PRC1 and PRC2 complex. We propose that these cells reflect a transitional stage between resting and dividing follicular B lymphocytes, and that they possibly represent the healthy precursors of nodal large B cell lymphomas. 相似文献
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Reuvit Halperin Arie Herman Abraham Golan Eran Hadas David Schneider Ian Bukovsky Raphael Ron-El 《American journal of reproductive immunology (New York, N.Y. : 1989)》1996,35(2):102-105
PROBLEM: To examine the relationship between the concentration of uterine fluid human decidua-associated protein (hDP) 200, identified as a monoclonal rheumatoid factor, and different phases of the menstrual cycle. METHODS: Sequential measurements of hDP 200 concentration in uterine fluid were performed in 11 normal ovulatory women, aged 22–36 years. The samples were collected in early proliferative phase, late proliferative phase, periovulatory period, early secretory phase, and late secretory phase. RESULTS: Consistent fluctuations of hDP 200 levels in uterine fluid were found throughout the menstrual cycle. High levels were found during early proliferative phase and periovulatory period related to significantly lower levels during late proliferative and early luteal phases. CONCLUSION: There is menstrual phase dependent variation in the uterine fluid levels of hDP 200. 相似文献
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28.
Graaff Esther de; Rouillard Patricia; J.Willems Patrick; P.T.Smits Arie; Rousseau Francois; A.Oostra Ben 《Human molecular genetics》1995,4(1):45-49
The fragile X syndrome is the most frequent cause of inheritedmental retardation. The molecular mechanism of the disorderis based on the expansion of a CGG repeat in the 5' UTR of theFMR1 gene In the majority of fragile X patients. The instabilityof this CGG repeat containing region is not restricted to theCGG repeat Itself but expands to the flanking region as well.We describe four unrelated fragile X patients that are mosaicfor both a full mutation and a small deletion in the CGG repeatcontaining region. Sequence analysis of the regions surroundingthe deletions showed that both the (CGG)n repeat and some flankingsequences were missing in all four patients. The 5' breakpointsof the deletions were found to be located between 7553bp proximal to the CGG repeat. This suggests the presence ofa hot spot region for deletions in the CGG repeat region ofthe FMR1 gene and emphasizes the instability of this regionIn the presence of an expanded CGG repeat. 相似文献
29.
Hosal SA Apel RL Freeman JL Azadian A Rosen IB LiVolsi VA Asa SL 《Endocrine pathology》1997,8(1):21-28
Molecular analyses of thyroid tumors have documented mutations in the tumor suppressor p53 gene almost exclusively in anaplastic
carcinomas. In contrast, immunohistochemistry has localized p53 in differentiated papillary and follicular thyroid cancers.
To establish the significance of p53 immunolocalization in these lesions, 78 thyroid tumors of follicular derivation were
examined. All tumors were classified by strict criteria and the extent of tumor was determined morphologically. Immunohistochemical
staining for p53 was performed on paraffin sections of formalin-fixed tumor tissue. The results of staining were correlated
with diagnosis, tumor extent and clinical outcome. Immunopositivity for p53 was diffuse and strong in all five anaplastic
carcinomas examined. There was no staining in five of six follicular adenomas. Four of nine follicular carcinomas had some
degree of nuclear staining, but this was focal; all nine tumors were confined to the thyroid at the time of examination. Of
49 papillary carcinomas, 26 were intrathyroidal, and 7 of these were occult; there was no p53 positivity in any occult lesion
and only 5 of the 19 palpable lesions stained. In contrast, among 23 papillary carcinomas with extrathyroidal extension or
metastases, only 9 were negative for p53 immunoreactivity. Five of seven tall cell papillary carcinomas and one of two insular
carcinomas had p53 immunopositivity and this correlated with aggressive behavior. These results support the tumorigenic role
of p53 mutations postulated for anaplastic thyroid carcinomas and indicate that localization of p53 by immunohistochemistry
is a useful prognostic index of clinical behavior in differentiated thyroid carcinomas of follicular cell derivation. 相似文献
30.
Sarah A. Collier Li Deng Elizabeth A. Adam Katharine M. Benedict Elizabeth M. Beshearse Anna J. Blackstock Beau B. Bruce Gordana Derado Chris Edens Kathleen E. Fullerton Julia W. Gargano Aimee L. Geissler Aron J. Hall Arie H. Havelaar Vincent R. Hill Robert M. Hoekstra Sujan C. Reddy Elaine Scallan Erin K. Stokes Jonathan S. Yoder Michael J. Beach 《Emerging infectious diseases》2021,27(1):140
Provision of safe drinking water in the United States is a great public health achievement. However, new waterborne disease challenges have emerged (e.g., aging infrastructure, chlorine-tolerant and biofilm-related pathogens, increased recreational water use). Comprehensive estimates of the health burden for all water exposure routes (ingestion, contact, inhalation) and sources (drinking, recreational, environmental) are needed. We estimated total illnesses, emergency department (ED) visits, hospitalizations, deaths, and direct healthcare costs for 17 waterborne infectious diseases. About 7.15 million waterborne illnesses occur annually (95% credible interval [CrI] 3.88 million–12.0 million), results in 601,000 ED visits (95% CrI 364,000–866,000), 118,000 hospitalizations (95% CrI 86,800–150,000), and 6,630 deaths (95% CrI 4,520–8,870) and incurring US $3.33 billion (95% CrI 1.37 billion–8.77 billion) in direct healthcare costs. Otitis externa and norovirus infection were the most common illnesses. Most hospitalizations and deaths were caused by biofilm-associated pathogens (nontuberculous mycobacteria, Pseudomonas, Legionella), costing US $2.39 billion annually. 相似文献