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Increased mucosal inflammatory cytokines in children with Helicobacter pylori-associated gastritis 总被引:2,自引:0,他引:2
N Kütükçüler S Aydogdu D Göksen S çaglayan RV Yagcyi 《Acta paediatrica (Oslo, Norway : 1992)》1997,86(9):928-931
The concentrations of tumour necrosis factor-alpha (TNF-α), interleukin-6 (IL-6) and IL-1-β in tissue homogenates of gastric mucosal biopsy specimens, and in gastric juice samples from Helicobacter pylori-positive and -negative children, were determined. The study population comprised 30 children with recurrent abdominal pain attending upper gastrointestinal endoscopy. Of these patients 18 were infected with H. pylori. Cytokine concentrations in gastric biopsy homogenate supernatants and in gastric juice were measured by enzyme-linked immunosorbent assay (ELISA). TNF-α levels in gastric juice and in gastric biopsy homogenate supernatants in patients with H. pylori-positive gastritis were found to be significantly higher than those in children without H. pylori infection. IL-6 levels were also higher in H. pylori -infected subjects, but the difference in IL-6 concentrations measured in gastric juice and biopsy homogenate supernatants did not reach statistical significance. IL-1-β concentrations in both specimens showed no significant difference between the two groups of children. It was suggested that increased levels of inflammatory cytokines, especially TNF-α and IL-6 generated locally within the gastric mucosa might be implicated in the pathogenesis of H. pylori-associated gastritis in childhood. 相似文献
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Ronny A. Bell PhD MS ; Sara A. Quandt PhD ; Thomas A. Arcury PhD ; Beverly M. Snively PhD ; Jeanette M. Stafford MS ; Shannon L. Smith MA ; Anne H. Skelly PhD RN 《The Journal of rural health》2005,21(3):198-205
PURPOSE: Residents in rural communities in the United States, especially ethnic minority group members, have limited access to primary and specialty health care that is critical for diabetes management. This study examines primary and specialty medical care utilization among a rural, ethnically diverse, older adult population with diabetes. METHODS: Data were drawn from a cross-sectional face-to-face survey of randomly selected African American (n=220), Native American (n=181), and white (n=297) Medicare beneficiaries > or =65 years old with diabetes in 2 rural counties in central North Carolina. Participants were asked about utilization of a primary care doctor and of specialists (nutritionist, diabetes specialist, eye doctor, bladder specialist, kidney specialist, heart specialist, foot specialist) in the past year. FINDINGS: Virtually all respondents (99.0%) reported having a primary care doctor and seeing that doctor in the past year. About 42% reported seeing a doctor for diabetes-related care. On average, participants reported seeing 2 specialists in the past year, and 54% reported i seeing >1 specialist. Few reported seeing a diabetes specialist (5.7%), nutritionist (10.9%), or kidney specialist (17.5%). African Americans were more likely than others to report seeing a foot specialist (P < .01), while men were more likely than women to have seen bladder specialist (P = .02), kidney specialist (P = .001), and heart specialist (P = .004), after adjusting for potential confounders. Predictors of the number of specialists seen include gender, education, poverty status, diabetes medication use, and self-rated health. CONCLUSIONS: These data indicate low utilization of specialty diabetes care providers across ethnic groups and reflect the importance of primary care providers in diabetes care in rural areas. 相似文献
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An acquired G-CSF receptor mutation results in increased proliferation of CMML cells from a patient with severe congenital neutropenia. 总被引:1,自引:0,他引:1
M Germeshausen H Schulze C Kratz L Wilkens R Repp K Shannon K Welte M Ballmaier 《Leukemia》2005,19(4):611-617
Severe congenital neutropenia (CN) is characterized by a maturation arrest of myelopoiesis at the promyelocyte stage. Treatment with pharmacological doses of recombinant human granulocyte colony-stimulating factor (rh-G-CSF) stimulates neutrophil production and decreases the risk of major infectious complications. However, approximately 15% of CN patients develop myeloid malignancies that have been associated with somatic mutations in the G-CSF receptor (G-CSFR) and RAS genes as well as with acquired monosomy 7. We report a CN patient with chronic myelomonocytic leukemia (CMML) who never received rh-G-CSF. Molecular analysis demonstrated a somatic G-CSFR mutation (C2390T), which led to expression of a truncated G-CSFR protein in the CMML. Normal G-CSFR expression was unexpectedly absent in primary and cultured CMML. In addition, CMML cells showed monosomy 7 and an oncogenic NRAS mutation. In vitro culture revealed a G-CSF-dependent proliferation of CMML cells, which subsequently differentiated along the monocytic/macrophage lineage. Our results provide direct evidence for the in vivo expression of a truncated G-CSFR in leukemic cells, which emerged in the absence of rh-G-CSF treatment and transduces proliferative signals. 相似文献
97.
Elizabeth Tan-Chiu Greg Yothers Edward Romond Charles E Geyer Michael Ewer Deborah Keefe Richard P Shannon Sandra M Swain Ann Brown Louis Fehrenbacher Victor G Vogel Thomas E Seay Priya Rastogi Eleftherios P Mamounas Norman Wolmark John Bryant 《Journal of clinical oncology》2005,23(31):7811-7819
PURPOSE: Trastuzumab is effective in treating human epidermal growth factor receptor 2 (HER2) -positive breast cancer, but it increases frequency of cardiac dysfunction (CD) when used with or after anthracyclines. PATIENTS AND METHODS: National Surgical Adjuvant Breast and Bowel Project trial B-31 compared doxorubicin and cyclophosphamide (AC) followed by paclitaxel with AC followed by paclitaxel plus 52 weeks of trastuzumab beginning concurrently with paclitaxel in patients with node-positive, HER2-positive breast cancer. Initiation of trastuzumab required normal post-AC left ventricular ejection fraction (LVEF) on multiple-gated acquisition scan. If symptoms suggestive of congestive heart failure (CHF) developed, source documents were blindly reviewed by an independent panel of cardiologists to determine whether criteria were met for a cardiac event (CE), which was defined as New York Heart Association class III or IV CHF or possible/probable cardiac death. Frequencies of CEs were compared between arms. RESULTS: Among patients with normal post-AC LVEF who began post-AC treatment, five of 814 control patients subsequently had confirmed CEs (four CHFs and one cardiac death) compared with 31 of 850 trastuzumab-treated patients (31 CHFs and no cardiac deaths). The difference in cumulative incidence at 3 years was 3.3% (4.1% for trastuzumab-treated patients minus 0.8% for control patients; 95% CI, 1.7% to 4.9%). Twenty-seven of the 31 patients in the trastuzumab arm have been followed for > or = 6 months after diagnosis of a CE; 26 were asymptomatic at last assessment, and 18 remained on cardiac medication. CHFs were more frequent in older patients and patients with marginal post-AC LVEF. Fourteen percent of patients discontinued trastuzumab because of asymptomatic decreases in LVEF; 4% discontinued trastuzumab because of symptomatic cardiotoxicity. CONCLUSION: Administering trastuzumab with paclitaxel after AC increases incidence of CHF and lesser CD. Potential cardiotoxicity should be carefully considered when discussing benefits and risks of this therapy. 相似文献
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