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101.
Effect of interleukin 1 polymorphisms on gastric mucosal interleukin 1beta production in Helicobacter pylori infection 总被引:20,自引:0,他引:20
Hwang IR Kodama T Kikuchi S Sakai K Peterson LE Graham DY Yamaoka Y 《Gastroenterology》2002,123(6):1793-1803
BACKGROUND & AIMS: Although epidemiological studies suggest that interleukin (IL)-1 genetic polymorphisms are involved in Helicobacter pylori-related gastric carcinogenesis, the data are conflicting regarding the effects of these polymorphisms on IL-1beta production. METHODS: IL-1B-511 polymorphism was genotyped by polymerase chain reaction (PCR)-restriction fragment length polymorphism, and IL-1RN variable number of tandem repeats was determined by PCR. Mucosal IL-1beta levels were measured by enzyme-linked immunosorbent assay. To determine which factors influence mucosal IL-1beta levels, gastric inflammation, and atrophy, multiple regression analyses were performed. RESULTS: We studied 117 H. pylori-infected Japanese patients. Carriers of the IL-1B-511T/T genotype or IL-1RN*2 allele had higher mucosal IL-1beta levels than noncarriers (partial regression coefficient [PRC] +/- SE), TT versus CC: 37.6 +/- 6 [antrum] and 32.1 +/- 6 [corpus] pg/mg protein (P < 0.001 for each), *1/*2 versus *1/*1: 24 +/- 8 [antrum] (P <0.01) and 36.5 +/- 7 [corpus] (P <0.001). Simultaneous carriers of IL-1B-511T/T genotype and IL-1RN*2 allele had the highest IL-1beta levels (82.9 +/- 12 [antrum] and 87.2 +/- 11 [corpus]) and showed a synergistic effect between 2 loci. The *1/*2 carriers were closely related to atrophy (PRC +/- SE; 0.87 +/- 0.4 [antrum] and 0.93 +/- 0.4 [corpus], P < 0.05), whereas being a carrier of the -511T/T genotype was related to severe gastric inflammation. CONCLUSIONS: IL-1 genetic polymorphisms influenced H. pylori-related gastric mucosal IL-1beta levels and were related to gastric inflammation and atrophy, factors thought to be important in gastric carcinogenesis. 相似文献
102.
103.
McMurray J Cohen-Solal A Dietz R Eichhorn E Erhardt L Hobbs FD Krum H Maggioni A McKelvie RS Piña IL Soler-Soler J Swedberg K 《European journal of heart failure》2005,7(5):710-721
Surveys of prescribing patterns in both hospitals and primary care have usually shown delays in translating the evidence from clinical trials of pharmacological agents into clinical practice, thereby denying patients with heart failure (HF) the benefits of drug treatments proven to improve well-being and prolong life. This may be due to unfamiliarity with the evidence-base for these therapies, the clinical guidelines recommending the use of these treatments or both, as well as concerns regarding adverse events. ACE inhibitors have long been the cornerstone of therapy for systolic HF irrespective of aetiology. Recent trials have now shown that treatment with beta-blockers, aldosterone antagonists and angiotensin receptor blockers also leads to substantial improvements in outcome. In order to accelerate the safe uptake of these treatments and to ensure that all eligible patients receive the most appropriate medications, a clear and concise set of clinical recommendations has been prepared by a group of clinicians with practical expertise in the management of HF. The objective of these recommendations is to provide practical guidance for non-specialists, in order to increase the use of evidenced based therapy for HF. These practical recommendations are meant to serve as a supplement to, rather than replacement of, existing HF guidelines. 相似文献
104.
Li H Groop L Nilsson A Weng J Tuomi T 《The Journal of clinical endocrinology and metabolism》2003,88(6):2767-2774
Our previous results have suggested that genes outside the human leukocyte antigen (HLA) class II locus may affect the phenotype of type 2 diabetic patients from families with both type 1 and type 2 diabetes (mixed type 1/2). To study whether the TNF alpha gene could be such a modifying gene, we studied TNF alpha promoter polymorphisms (G-->A substitution at positions -308 and -238) in relation to HLA-DQB1 genotypes in type 2 patients from mixed type 1/2 families or common type 2 diabetes families as well as in patients with adult-onset type 1 diabetes and control subjects. The TNF alpha(308) AA/AG genotype frequency was increased in adult onset type 1 patients (55%, 69 of 126), but it was similar in type 2 patients from type 1/2 families (35%, 33/93) or common type 2 families (31%, 122 of 395), compared with controls (33%, 95/284; P < 0.0001 vs. type 1). The TNF alpha(308) A and DQB1*02 alleles were in linkage disequilibrium in type 1 patients (Ds = 0.81; P < 0.001 vs. Ds = 0.25 in controls) and type 2 patients from type 1/2 families (Ds = 0.59, P < 0.05 vs. controls) but not in common type 2 patients (Ds = 0.39). The polymorphism was associated with an insulin-deficient phenotype in the type 2 patients from type 1/2 families only together with DQB*02, whereas the common type 2 patients with AA/AG had lower waist to hip ratio [0.92 (0.12) vs. 0.94 (0.11), P = 0.008] and lower fasting C-peptide concentration [0.48 (0.47) vs. 0.62 (0.46) nmol/liter, P = 0.020] than those with GG, independently of the presence of DQB1*02. In conclusion, TNF alpha is unlikely to be the second gene in the HLA area responsible for our previous findings in type 1/2 patients. However, we could show an association between TNF alpha(308) polymorphism and the phenotype of common type 2 diabetes. 相似文献
105.
Histological patterns of gastritis in H. pylori-infected individuals with a family history of gastric cancer 总被引:9,自引:0,他引:9
Sepulveda A Peterson LE Shelton J Gutierrez O Graham DY 《The American journal of gastroenterology》2002,97(6):1365-1370
OBJECTIVE: Different types of chronic gastritis, including antral predominant, corpus predominant, and multifocal pangastritis, are associated with Helicobacter pylori infection. Specific patterns of H. pylori gastritis that might characterize individuals with family histories of noncardia gastric cancer (GC) were investigated. METHODS: Histopathological changes associated with H. pylori gastritis were assessed in 111 individuals with family histories of GC and in 77 without from a region with high prevalence of H. pylori infection and GC. Gastric biopsies were taken from 12 sites (antrum, five; corpus, six; and cardia, one). RESULTS: Individuals (age < 36 yr) with family histories of GC developed pangastritis and had higher H. pylori bacterial scores (p < 0.05) in the gastric corpus, whereas those without family histories of GC typically had antral predominant gastritis. The correlation between density of polymorphonuclear leukocytes and density of H. pylori at each biopsy site was statistically significant (p < 0.01). Pangastritis was associated with a higher density of lymphoid aggregates and follicles (p < 0.05) in the corpus of younger individuals (age < 36) and in the antrum of older individuals (age > or = 48) with positive family histories of GC. CONCLUSIONS: Pangastritis and high lymphoid follicle density associated with H. pylori infection were found in patients with family histories of GC. Because a family history of gastric carcinoma is associated with increased risk of gastric cancer development, characterization of histological patterns of gastritis may be applicable to gastric cancer screening and surveillance, especially in relatively young at-risk populations. 相似文献
106.
The Cdx2 homeobox gene has a tumour suppressor function in the distal colon in addition to a homeotic role during gut development 总被引:6,自引:0,他引:6
Bonhomme C Duluc I Martin E Chawengsaksophak K Chenard MP Kedinger M Beck F Freund JN Domon-Dell C 《Gut》2003,52(10):1465-1471
BACKGROUND: During development, the homeobox gene Cdx2 exerts a homeotic function, providing the positional information necessary for correct specification of the midgut endoderm. This is illustrated by the non-neoplastic gastric-type heteroplasias present at birth in the pericaecal region of Cdx2(+/-) mice. Furthermore, intestinal expression of Cdx2 continues throughout life but diminishes in colorectal cancers compared with adjacent normal tissue, suggesting a role in tumorigenesis. Aim: To investigate the consequence of altered Cdx2 expression on colon tumour initiation and/or progression. METHODS: Heterozygous Cdx2(+/-) mice were analysed for spontaneous malignant tumours and for tumour development after treatment with a DNA mutagen, azoxymethane. RESULTS: Cdx2(+/-) mice did not spontaneously develop malignant tumours. After azoxymethane treatment, the gastric-like heteroplasias in the pericaecal region did not evolve into cancer indicating that they are not precancerous lesions. However, azoxymethane treated Cdx2(+/-) mice developed tumours specifically in the distal colon 12 weeks after azoxymethane treatment whereas no tumours were found in wild-type littermates at this stage. Histopathological and molecular analyses indicated that these tumours were invasive adenocarcinomas that recapitulated the malignant sequence observed in the majority of sporadic colorectal cancers in human. In addition, we found that the colonic epithelium was less sensitive to radiation induced apoptosis in Cdx2(+/-) than in wild-type mice. CONCLUSION: This study provides the first experimental evidence that Cdx2 is a tumour suppressor gene involved in cancer progression in the distal colon. This action in adults is functionally and geographically distinct from its homeotic role during gut development. 相似文献
107.
Castaños-Vélez E Heiden T Lindvall C Capello D Sandlund A Imreh S Blennow E Andersson LC Gaidano G Nordenskjöld M Biberfeld P 《AIDS research and human retroviruses》2002,18(5):383-390
Simian AIDS-related lymphomas (sARL) of cynomolgus monkeys infected with a simian immunodeficiency virus (SIVsm) were studied in relation to growth in severe combined immunodeficient (SCID) mice, karyotype abnormalities, and DNA sequence of the first noncoding region of the Bcl-6 gene. The tumors were diffuse large B cell lymphomas and expressed a simian homolog to Epstein-Barr virus (HVMF-1) in 12 of 13 primary tumors and corresponding cell lines. A tested cell line was tumorigenic in SCID mice. Tumors in the SCID mice showed cell growth features similar to those in the original lymphoma, suggesting that no subpopulation with growth advantage was selected for in the mice. Spectral karyotype analysis of sARL cell lines showed normal cytogenetic features except for a trisomy of monkey chromosome 2 (corresponding to human chromosomes 7 and 21) in two of five sARL lines, which was not recovered in SCID tumors established from the same cell line. Sequence analysis of a Bcl-6 gene fragment showed sequence variations indicative of population polymorphism(s) in 10 of 13 sARLs, and no evidence of Bcl-6 mutations. Thus Bcl-6 mutations in the first noncoding region are irrelevant for sARL development in cynomolgus monkeys and for tumorigenicity of sARL cell lines. We also demonstrate that no cytogenetic alterations are needed for the development of highly aggressive lymphomas in the SIV-immunosuppressed host. 相似文献
108.
Deininger M Pönisch W Krahl R Leiblein S Edel E Lange T Fiedler F Freund M Franke A Pasold R von Grünhagen U Herold M Dölken G Hoffmann FA Uhle R Schultze W Steglich J Schwarzer A Richter P Winkelmann C Kettner E Dachselt K Subert R Schwalbe E Doepper J Helbig W Niederwieser D;East German Study Group Haematology/Oncology 《Bone marrow transplantation》2001,27(11):1125-1132
Mobilised peripheral blood stem cells are widely used for autografting in patients with chronic myeloid leukaemia (CML) and it is generally thought that a high proportion of Ph-negative progenitor cells in the graft is desirable. We report here the results of 91 stem cell mobilisations performed with various chemotherapy regimens followed by G-CSF. We show that mobilisation of Ph-negative cells is possible after diagnosis as well as in advanced stages of the disease. The yield of Ph-negative cells is highly dependent on the chemotherapy regimen: while the combination of idarubicin and cytarabin for 3-5 days (IC3-5) mobilised Ph-negative cells in most patients, high-dose cyclophosphamide was ineffective. Mobilisation of Ph-negative progenitor cells after IC3 was at least as effective as after IC5; however, less apheresis sessions were required, and toxicity was much reduced after IC3. Compared to historical controls, IC was equally effective as the widely used ICE/miniICE (idarubicin, cytarabin, etoposide) protocol. No correlation was found between graft quality and the cytogenetic response to subsequent treatment with interferon-alpha. We conclude that IC3 is an effective and well-tolerated regimen for mobilising Ph-negative cells that compares well with more aggressive approaches such as IC5 and ICE/miniICE. 相似文献
109.
Brain monoglyceride lipase participating in endocannabinoid inactivation 总被引:24,自引:0,他引:24
Dinh TP Carpenter D Leslie FM Freund TF Katona I Sensi SL Kathuria S Piomelli D 《Proceedings of the National Academy of Sciences of the United States of America》2002,99(16):10819-10824
The endogenous cannabinoids (endocannabinoids) are lipid molecules that may mediate retrograde signaling at central synapses and other forms of short-range neuronal communication. The monoglyceride 2-arachidonoylglycerol (2-AG) meets several criteria of an endocannabinoid substance: (i) it activates cannabinoid receptors; (ii) it is produced by neurons in an activity-dependent manner; and (iii) it is rapidly eliminated. 2-AG inactivation is only partially understood, but it may occur by transport into cells and enzymatic hydrolysis. Here we tested the hypothesis that monoglyceride lipase (MGL), a serine hydrolase that converts monoglycerides to fatty acid and glycerol, participates in 2-AG inactivation. We cloned MGL by homology from a rat brain cDNA library. Its cDNA sequence encoded for a 303-aa protein with a calculated molecular weight of 33,367 daltons. Northern blot and in situ hybridization analyses revealed that MGL mRNA is heterogeneously expressed in the rat brain, with highest levels in regions where CB(1) cannabinoid receptors are also present (hippocampus, cortex, anterior thalamus, and cerebellum). Immunohistochemical studies in the hippocampus showed that MGL distribution has striking laminar specificity, suggesting a presynaptic localization of the enzyme. Adenovirus-mediated transfer of MGL cDNA into rat cortical neurons increased MGL expression and attenuated N-methyl-D-aspartate/carbachol-induced 2-AG accumulation in these cells. No such effect was observed on the accumulation of anandamide, another endocannabinoid lipid. The results suggest that hydrolysis by means of MGL is a primary mechanism for 2-AG inactivation in intact neurons. 相似文献
110.
Ostgren CJ Lindblad U Melander O Melander A Groop L Råstam L 《Journal of hypertension》2003,21(9):1657-1662
OBJECTIVE: This study explored whether the Pro12Ala polymorphism in the peroxisome proliferator-activated receptor-gamma (PPARgamma) is associated with blood pressure in subjects with type 2 diabetes. DESIGN: A community-based, cross-sectional observation study. SETTING: Primary care. PATIENTS: One hundred and ninety-two men and 192 women with type 2 diabetes who consecutively underwent annual follow-up. MAIN OUTCOME MEASURE: The PPARgammaPro12Ala genotype was determined by polymerase chain reaction-based techniques. Associations between genotype and blood pressure were analysed by linear regression and expressed as differences in blood pressure (delta) with 95% confidence interval (CI). RESULTS: The mean systolic blood pressure and the diastolic blood pressure were 160 mmHg (standard deviation = 22.8) and 84 mmHg (standard deviation = 9.6), respectively. Subjects with Pro/Ala (24%) or Ala/Ala (2%) had lower diastolic blood pressure (delta = 2.8; 95% CI, 0.6-5.0) when adjusted for age and gender compared with Pro/Pro subjects (74%). This association was restricted to men (delta = 4.4; 95% CI, 1.3-7.4), who also had a borderline significant difference in systolic blood pressure (delta = 6.9; 95% CI, -0.8 to 13.8). In men the difference in diastolic blood pressure remained after adjustment for age, body mass index, serum triglycerides, serum insulin and haemoglobin A(1c) (delta = 4.6; 95% CI, 1.1-8.1). A subanalysis of normotensive men (n = 100) confirmed the difference associated with the Pro12Ala polymorphism in diastolic blood pressure (delta = 5.2; 95% CI, 0.6-10.0). CONCLUSIONS: The common Pro12Ala polymorphism in PPARgamma is associated with lower diastolic blood pressure in male subjects with type 2 diabetes. 相似文献