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91.
BACKGROUND: Helicobacter pylori, the main cause of gastritis and peptic ulcer, has been associated with idiopathic chronic urticaria (ICU), an immunological skin disorder of unknown origin. Eosinophilic cationic protein (ECP) is a cytotoxic molecule secreted by the activated eosinophils involved in the pathogenesis of ICU. We assessed serum/gastric juice ECP levels and gastric mucosal eosinophil infiltration in ICU patients infected or not with H. pylori and evaluated the modification after bacterium eradication. METHODS: 33 patients with ICU and 25 dyspeptic controls underwent upper gastrointestinal endoscopy for histological evaluation and assessment of H. pylori infection. One-week triple therapy was given to H. pylori-positive patients. Serum and gastric juice ECP levels, eosinophil infiltration from gastric mucosal sections and urticaria symptoms were evaluated in all patients at enrollment and 8 weeks after eradication. RESULTS: 19 of 33 (57%) ICU patients and 16 of 25 (64%) controls were found to be infected with H. pylori. Serum ECP was significantly higher in ICU patients compared to controls, regardless of infectious status. Gastric juice ECP and gastric eosinophil infiltration were significantly higher in infected ICU patients when compared both to uninfected ICU patients and controls. H. pylori eradication determined a significant decrease in gastric juice ECP and gastric eosinophil infiltration only in ICU patients. Moreover, a total or partial remission of urticaria symptoms was observed only in ICU patients in whom the bacterium was eradicated. CONCLUSIONS: Although H. pylori infection affects gastric juice ECP and eosinophil infiltration of ICU patients, the role of the bacterium in the pathogenesis of this skin disorder still remains uncertain.  相似文献   
92.
We assessed the incidence and determinants of bacteremia, pneumonia, and sinusitis/otitis in HIV-positive people receiving cotrimoxazole (CTX) or dapsone-pyrimethamine (DP) for primary prophylaxis of Pneumocystis carinii pneumonia (PCP) and toxoplasmic encephalitis (TE) within a randomized clinical trial. In total, 244 patients were randomized: 122 were assigned to CTX and 122 to DP. In the cohort, 22 bacteremia, 63 pneumonia, and 39 sinusitis/otitis cases were observed. Incidence rates of bacteremia, pneumonia, and sinusitis/otitis as well as the 2-year probability of remaining free from any bacterial infection were not significantly different between the two groups. At multivariate analysis, the risks of developing bacteremia and pneumonia were found to be independently increased by the use of a central venous catheter (hazard ratio [HR], 4.48; p <.05 and HR, 4.13; p <.01, respectively) and by hospitalization (HR, 28.82; p <.05 and HR, 10.15; p <.05, respectively). In conclusion, CTX at the dosage employed for primary PCP/TE prophylaxis does not seem to protect against bacterial infections more than second-line DP.  相似文献   
93.
Recent reports document resolution of human parvovirus B19-related pure red blood cell aplasia (PB19-PRCA) in HIV-infected patients upon commencement of highly active antiretroviral therapy (HAART). This article describes a patient with PB19-PRCA who, despite fully suppressive HAART, required cyclic administration of intravenous human immunoglobulin over a period of 17 months before PB19 seroconversion and subsequent resolution of relapsing severe anemia. All reports in the English literature describing PB19-related hematologic abnormalities in the post-HAART era are also described herein.  相似文献   
94.
95.
Dysmenorrhoea is a recurrent painful disease which causes physicaland psychological stress. The purpose of the present study wasto investigate whether there was a measurable derangement ofimmune cells and immune responses in women with severe primarydysmenorrhoea. On day 26 of one cycle and on days 1 and 3 ofthe following cycle we measured polyclonal, mitogen-inducedlymphocyte proliferation and -endorphin concentration in peripheralblood mononuclear cells obtained from 16 infertile women withnormal pelvis, of whom eight had and eight did not have thedisorder. In women with dysmenorrhoea, polyclonal mitogen-inducedlymphocyte proliferation was lower than in controls on all 3days considered, but the difference was statistically significantonly on day 26 (43 605 ± 9876 µg/ml versus 67 305± 15 249 µg/ml; P < 0.01). Monocyte -endorphinconcentrations in the patients with dysmenorrhoea were significantlyelevated on day 3 compared to controls (67.8 ± 24.3 pg/106cells versus 29.7 ± 6.9 pg/106 cells; P < 0.05). Ourresults demonstrate that immune responses are modified in patientswith primary dysmenorrhoea. These effects are independent ofcirculating hormone concentrations and are consistent with therole of dysmenorrhoea as a stressful event.  相似文献   
96.
The performance of the BD Phoenix Automated Microbiology System (BD Diagnostic Systems, Sparks, Md.) was assessed for identification (ID) and antimicrobial susceptibility testing (AST) for the majority of clinically encountered bacterial isolates in a European collaborative two-center trial. A total of 469 bacterial isolates of the genera Staphylococcus (275 isolates), Enterococcus (179 isolates), and Streptococcus (15 isolates, for ID only) were investigated; of these, 367 were single patient isolates, and 102 were challenge strains tested at one center. Sixty-four antimicrobial drugs were tested, including the following drug classes: aminoglycosides, beta-lactam antibiotics, beta-lactam-beta-lactamase inhibitors, carbapenems, cephems, folate antagonists, quinolones, glycopeptides, macrolides-lincosamides-streptogramin B (MLS), and others. Phoenix ID results were compared to those of the laboratories' routine ID systems (API 32 Staph, API 32 Strep, and VITEK 2 [bioMérieux, Marcy l'Etoile, France]); Phoenix AST results were compared to those of frozen standard broth microdilution (SBM) panels according to NCCLS guidelines (NCCLS document M 100-S 9, approved standard M 7-A 4). Discrepant results were repeated in duplicate. Concordant IDs of 97.1, 98.9, and 100% were observed for staphylococci, enterococci, and streptococci, respectively. For AST results the overall essential agreement was 93.3%; the category agreement was 97.3%; and the very major error rate, major error rate, and minor error rate were 1.2, 1.9, and 1.3%, respectively. In conclusion, the Phoenix ID results showed high agreement with results of the systems to which they were being compared; the AST performance was highly equivalent to that of the SBM reference method.  相似文献   
97.
OBJECTIVE: Estrogens increase serum thyroxine-binding globulin (TBG) and total thyroxine (TT4) concentrations. Serum free thyroxine (FT4) concentrations, however, remain normal. Raloxifene (RAL) is a selective estrogen receptor modulator used to treat postmenopausal osteoporosis. Data on the long-term effects of RAL on thyroid physiology are scanty. We evaluated the effects of RAL administration for 1 year on thyroid function in osteopenic, postmenopausal women. DESIGN: Fifty osteopenic, postmenopausal women were randomly assigned to receive either RAL (60 mg/day, n = 25) or placebo (PL, n = 25) for 1 year, in a double-blind study. Measurements of serum TBG, TT4, FT4, thyroid-stimulating hormone (TSH), thyroid hormone-binding ratio (THBR), FT4 index (FT4-I) and TT4/TBG ratio were carried out at baseline and after 4 and 12 months of therapy. RESULTS: Baseline values were similar in both treatment groups. Serum TBG concentrations were increased during RAL treatment from baseline values of 29.60 +/- 0.9 microg/mL to 31.45 +/- 1.33 and 32.34 +/- 1.37 microg/mL at 4 months and 1 year, respectively (P < 0.05, baseline v 1-year values) but were unchanged during PL treatment. A small, insignificant increase in TT4 and TSH concentrations occurred in the RAL group and no changes in the PL group. All other values were unchanged during either treatment. CONCLUSIONS: These results demonstrate that RAL significantly increased serum TBG levels, but the changes were small and not accompanied by changes in FT4-I, FT4, or TSH concentrations, suggesting that long-term RAL treatment is unlikely to clinically affect the thyroid status in euthyroid, postmenopausal women.  相似文献   
98.
The present study was undertaken with the aim to evaluate the prevalence of thermotolerant Campylobacter spp. in living pheasants in Italy. To achieve this goal, a total of 240 living pheasants, equally shared between female and male birds, were examined. Thermotolerant Campylobacter spp. was isolated in 104 out of 204 (43.3%) living pheasants analysed. Campylobacter coli (100%) and Campylobacter jejuni (13.5%) were identified by polymerase chain reaction. Adult pheasants showed a significantly higher prevalence value (P < 0.05) than younger pheasants.  相似文献   
99.
100.
Transplantation Centers using human cytomegalovirus (HCMV) antigenemia-based preemptive therapy will need to replace in the near future the antigenemia assay with a more standardized and automatable assay, such as a molecular assay quantifying HCMV DNA in blood (DNAemia). Thus, in view of replacing antigenemia with clinically safe cutoff values, DNAemia levels corresponding to antigenemia cutoffs guiding HCMV preemptive therapy were determined retrospectively in solid organ and hematopoietic stem cell transplant recipients (HSCTR) using an "in-house" quantitative PCR (QPCR) method. Since preemptive therapy had prevented appearance of HCMV disease in all patients tested, DNA cutoffs determined retrospectively had to be considered as safe clinically as antigenemia cutoffs used prospectively. However, in solid organ transplant recipients (SOTR), initiating preemptive therapy upon an antigenemia cutoff of 100 pp65-positive leukocytes, a DNAemia cutoff of 300,000 copies/ml blood had positive and negative predictive values of >90%, indicating that a DNAemia cutoff could achieve, in terms of prevention of HCMV disease, the same clinical results as the antigenemia cutoff. In HSCTR, initiating preemptive therapy upon first antigenemia positivity, a DNAemia cutoff of 10,000 copies/ml blood had a positive predictive value of >90%, indicating that the great majority of patients treated under the antigenemia guidance would have been treated also using this DNA cutoff. On the other hand, the negative predictive value of 28.6% indicated that two out of three HSCTR had been treated under the antigenemia guidance having the same levels of viral DNA as the untreated patients. The data suggest that a quantitative cutoff could be adopted as a guiding criterion for preemptive therapy also in HSCTR. Regression analysis allowed to determine the DNAemia (corresponding to QPCR) cutoff values for two commercial assays tested both in solid organ and HSCTR. Retrospective DNAemia cutoff values will be verified for safety in prospective trials.  相似文献   
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