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51.
BACKGROUND: Nitric oxide (NO) production catalyzed by iNOS (inducible NO synthase) is thought to take place mainly in macrophages after activation by inflammatory mediators. NO is subsequently oxidized to nitrite and nitrate, which are excreted in urine. The concentration of inflammatory mediators in small bowel biopsy specimens from patients with coeliac disease is increased. The latter could induce increased NO production by stimulation of intestinal macrophage iNOS, resulting in high levels of urinary NO oxidation products, nitrite and nitrate (NOx). AIM: In the present study we evaluated the urinary NOx/creatinine ratios in children with active coeliac disease (n = 22), coeliac disease patients on a gluten-free diet (n = 9), healthy (n = 11) and sick control children (n = 18). METHODS: The Griess reagent method was used for measuring urinary NOx. RESULTS: Median NOx/creatinine ratios of active coeliac disease patients, coeliac disease patients on a gluten-free diet, healthy and sick control patients were 1.21, 0.19, 0.10 and 0.13 mmol/mmol, respectively. All active coeliac disease patients showed increased NOx/ creatinine ratios. Urinary NOx/creatinine ratios of the active coeliac disease patients were significantly higher than those of healthy controls (p < 0.0001), sick controls (p < 0.0001) and coeliac disease patients on a gluten-free diet (p < 0.0001). CONCLUSION: The urinary NOx/creatinine ratio is increased in patients with active coeliac disease and reverts to normal on a gluten-free diet.  相似文献   
52.
The EuroQoL EQ-5D and MOS SF-36 are two generic quality of life measures that differ significantly in their design (the former being an index and the latter a profile). Both have been extensively used in evaluating interventions in acute disease. This study tested their comparative performance in a survey of patients with relapsing-remitting multiple sclerosis (MS).
METHODS: 309 patients with diagnosed relapsing-remitting MS were identified through the records of 5 specialist centers in North West England. Patients were contacted by telephone by a specialist MS nurse and asked to complete a set of questionnaires distributed by mail. The questionnaire booklet reproduced the English version of SF-36, together with the EQ-5D and a self completion form of the Barthel. Minimal additional background information was obtained from all respondents; 4 weeks following their completion of the initial booklet, a second identical booklet was sent to the first 200 initial respondents. Patients in this re-test sub-group were asked whether their health status had improved, deteriorated, or remained unchanged over the intervening period.
RESULTS: Of the 200 patients in the test/re-test subgroup, 144 (72%) replied on both occasions. Paired t-tests for the PCS, MCS, and general health perception scores on the SF-36 failed to generate comprehensive evidence of reliability. The weighted index form of the EQ-5D and the visual analogue scale self-ratings provided superior evidence of reliability. Standardized response means for both measures confirmed this general pattern.
CONCLUSION: EQ-5D performs satisfactorily as a generic measure of health-related quality of life in patients with MS.  相似文献   
53.
Bile reflux has been implicated in the pathogenesis and malignant degeneration of Barrett’s esophagus, but clinical studies in patients with adenocareinoma arising in Barrett’s esophagus are lacking. Ambulatory esophageal measurement of acid and bile reflux was performed with the previously validated fiberoptic bilirubin monitoring system (Bilitec) combined with a pH probe in 20 asymptomatie volunteers, 19 patients with gastroesophageal reflux disease (GERD) but no mucosal injury, 45 patients with GERD and erosive esophagitis, 33 patients with GERD and Barrett’s esophagus, and 14 patients with early adenocarcinoma arising in Barrett’s esophagus. Repeat studies were done in 15 patients under medical acid suppression and 16 patients after laparoscopie Nissen fundoplication. The mean esophageal bile exposure time showed an exponential increase from GERD patients without esophagitis to those with erosive esophagitis and benign Barrett’s esophagus and was highest in patients with early carcinoma in Barrett’s esophagus (P <0.01). Pathologic esophageal bile exposure was documented in 18 (54.5%) of 33 patients with benign Barrett’s esophagus and 11 (78.6%) of 14 patients with early adenoearcinoma in Barrett’s esophagus. Nissen fundoplieation but not medical acid suppression resulted in complete suppression of bile reflux. Bile reflux into the esophagus is particularly prevalent in patients with Barrett’s esophagus and early cancer. Bile reflux into the esophagus can be completely suppressed by Nissen fundoplication but not medical acid suppression alone. (J GASTROINTEST SURG 1998;2:333-341.) Presented at the Thirty-Eighth Annual Meeting of The Society for Surgery of the Alimentary Tract, Washington, D.C., May 11–14, 1997  相似文献   
54.
Concentrations of plasma fibrinopeptide A (FPA) were measured by radioimmunoassay in 50 patients with venous thromboembolism or disseminated intravascular coagulation or both. A consistent discrepancy was observed in values obtained with two anti-FPA antisera. Analysis of extracts from plasma of these patients by high-performance liquid chromatography (HPLC) revealed the presence of a phosphorylated and an unphosphorylated form of the A peptide. Differences in concentrations of FPA measured with the two antisera could be accounted for by their different reactivity with phosphorylated FPA (FPA-P). The differences were abolished by treatment with alkaline phosphatase. A good correlation was observed between the FPA-P content of free A- peptide material and of fibrinogen in plasma as determined by HPLC (r = .88, P less than .001, n = 11). In patients with elevated FPA levels, the mean FPA-P content of fibrinogen was significantly higher (P less than .002, n = 13) than in patients with normal FPA levels (n = 8) and in healthy controls (n = 14). Phosphorus in fibrinogen did not correlate with fibrinogen degradation products or fibrinogen levels and became normal on adequate anticoagulation. Therefore, blood-clotting activation may lead to a high phosphate content of fibrinogen and of free FPA in plasma.  相似文献   
55.
In order to test the hypothesis that integrin and uteroglobin (UG) expression in cultured endometrial cells are affected by hormone treatment, Ishikawa-CH endometrial cancer cells were cultured and exposed to oestradiol or oestradiol and progesterone regimens and assayed using immunohistochemistry. We evaluated the intensity of immunohistochemical staining for the integrin monomers alpha(v) and beta1, the dimers alpha(v)beta3 and alpha(v)beta6, and for the secretory protein uteroglobin under various experimental conditions. Cells grown in control media stained positively for the integrin monomers alpha(v) and beta1, the dimer alpha(v)beta3, and for UG. Oestradiol and sequential oestradiol/progesterone reversibly suppressed staining for the dimer alpha(v)beta3. Hormone treatment had no effect on the staining of the beta1 and alpha(v) monomers or UG. The alpha(v)beta6 dimer antibody did not stain under any experimental treatment conditions. These data indicate that expression of the integrin complex alpha(v)beta3 is reversibly suppressed by oestradiol in Ishikawa cells and that these cells may be a good model for studying hormone-driven molecular changes in endometrium.   相似文献   
56.
We investigated the ability of blood B cells, bone marrow (BM) plasma cells, and terminal leukemic plasma cells (T-PCL) from patients with multiple myeloma (MM) to migrate on extracellular matrix proteins. Hyaluronan (HA), but not collagen type I, collagen type IV, or laminin, promoted migration of MM blood B cells, as determined by time-lapse video microscopy. Between 13% and 20% of MM blood B cells migrated on HA with an average velocity of 19 micron/min, and greater than 75% of MM blood B cells exhibited vigorous cell movement and plasma membrane deformation, as did circulating T-PCL and extraskeletal plasma cells from patients with MM. In contrast, plasma cells obtained from BM of patients with MM lacked motility on all substrates tested and did not exhibit cell membrane protrusions or cellular deformation. MM blood B cells and MM plasma cells from all sources examined expressed the HA- binding receptors receptor for HA-mediated motility (RHAMM) and CD44. On circulating MM B cells, both RHAMM and CD44 participated in HA- binding, indicating their expression ex vivo in an activated conformation. In contrast, for the majority of BM plasma cells in the majority of patients with MM, expression of RHAMM or CD44 was not accompanied by HA binding. A minority of patients did have HA-binding BM plasma cells, involving both RHAMM and CD44, as evidenced by partial blocking with monoclonal antibodies (MoAbs) to RHAMM or to CD44. Despite HA binding by both RHAMM and CD44, migration of MM blood B cells on HA was inhibited by anti-RHAMM but not by anti-CD44 MoAbs, indicating that RHAMM but not CD44 mediates motility on HA. Thus, circulating B and plasma cells in MM exhibit RHAMM- and HA-dependent motile behavior indicative of migratory potential, while BM plasma cells are sessile. We speculate that a subset(s) of circulating B or plasma cells mediates malignant spread in myeloma.  相似文献   
57.
58.
Large granular lymphocyte (LGL) leukemia is a rare disease characterized by clonal expansion of LGL associated with chronic neutropenia, multiple auto-antibodies, and occasionally polyarthritis. We studied cell surface antigen expression and functional activity of leukemic LGL from ten such patients. Using two-color flow cytometric analysis, we found that leukemic LGL from all ten patients expressed the CD3 and HNK-1 markers, while cells from only four patients expressed IgG Fc receptors (FcR). The LGL leukemic cells had little or no NK activity (defined as MHC-nonrestricted cytotoxicity against K562 target cells); however, NK activity could be induced in leukemic LGL by in vitro treatment with as little as 0.05 microgram/mL of anti-CD3 monoclonal antibody. Cell sorting experiments demonstrated that NK activity was induced in CD3+ leukemic LGL (either CD3+, HNK-1+ or CD3+, FcR+) with anti-CD3 monoclonal antibody but not in normal CD3+, FcR- T cells. Treatment with purified interleukin 2 (IL 2) also caused direct activation of some CD3+ leukemic LGL. Despite induction with anti-CD3 MAb or IL 2, activated leukemic LGL did not proliferate or express high density IL 2 receptors detectable by cell sorter analysis. Treatment with alpha interferon had minimal effect on NK activity of LGL leukemic cells. These results suggest that leukemic LGL may provide a useful model for examining the signals required for LGL maturation and activation.  相似文献   
59.
Platelets gradually lose their disc shape during storage. The authors studied simultaneous changes in platelet cytosolic Ca2+ (Cai) and the polymerization state of actin as related to the shape. Platelet concentrates were stored under blood bank conditions for up to 10 days. Aliquots were removed and analyzed as follows: platelet Cai and increments in Cai induced by adenosine diphosphate (ADP) were determined by fluorescence of fura-2-loaded cells; loss of disc shape was determined by differences in light scattering intensity induced by stirring; and the ratio of globular and total actin (G/T) of platelets in plasma was determined by a modification of the DNase inhibition assay. Globular actin was found to be 86 +/- 3% of total actin in freshly drawn platelets suspended in plasma. The following changes occurred during storage: G/T in platelet concentrates increased from 63 +/- 5 (day 0) to 74 +/- 2% in the first 24 hours then fell to 33 +/- 6% by day 10. The percent discoid platelets also increased from day 0 to day 1 then fell in the ensuing days. There was an initial drop in Cai from day 0 to day 1, after which Cai increased on days 3 and 6. Globular actin polymerization during storage closely correlated with the change in percent discs (r = 0.95). During 6 days of storage Cai was highly correlated with shape change (r = 0.97) and to a lesser extent (r = 0.87) with the ratio of globular actin. The authors conclude that actin polymerization, shape, and Ca2+ change in a related fashion during storage.  相似文献   
60.
Lozzio  BB; Machado  EA; Mitchell  J; Lozzio  CB; Wust  CJ; Golde  DW 《Blood》1983,61(6):1045-1053
Six human hematopoetic cell lines were successfully heterotransplanted into athymic (nude) and asplenic-athymic (lasat) neonatal mice. The tumors arising from leukemia and lymphoma cells could then be serially transplanted into adult nude mice. Seven days after the fourth serial mouse passage, each mouse was treated with goat immune gamma globulin against K-562 cells. One control group was treated similarly, but with nonimmune (normal) gamma globulin, while another control group was not treated. The goat gamma globulin was not toxic for nude and lasat mice, and the immune, but not the normal, gamma globulin suppressed local subcutaneous growth of myelosarcomas, lymphosarcomas, and Burkitt lymphoma cells. On the other hand, the growth of lung, breast, and prostatic carcinomas and a melanoma of human origin were not altered by the immune gamma globulin. Since suppression of cell growth occurred equally well in decomplemented mice, a complement-mediated cytotoxicity apparently cannot be considered as responsible for the abrogation. The Fab fragment of the immunoglobulin did not suppress the growth of the myelosarcomas. We conclude that antibody suppression of the in vivo proliferation was specific for malignant hematopoietic cells and that the Fc portion of IgG is necessary for in vivo cytolysis of leukemia cells. The most probable mechanisms are direct antibody cytolysis and antibody-dependent macrophage-mediated cytotoxicity.  相似文献   
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