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51.
We used light and electron microscopy to analyze the eyelid inflammation that develops in transgenic mice that overexpress interleukin-4 (IL-4; Tepper et al, Cell 62:457, 1990). Analysis of alkaline Giemsa-stained plastic sections examined by light microscopy (Dvorak et al, J Exp Med 132:558, 1970), as well as by routine transmission electron microscopy, indicated that the mast cells in the inflammatory eyelid lesions were undergoing piecemeal degranulation, a form of secretion in which the cells' cytoplasmic granules exhibit characteristic morphologic changes that are thought to be associated with the prolonged, vesicle-mediated release of the granules' constituents. Moreover, by using a newly reported enzyme affinity-gold method, which stains histamine based on binding to diamine oxidase-gold (Dvorak et al, J Histochem Cytochem 41:787, 1993), we show that these activated mast cells had released much of their histamine content. The eyelid lesions also exhibited increased numbers of mast cells; interstitial fibrosis, particularly around cutaneous nerves and blood vessels; activated fibroblasts; focal axonal damage; venules with endothelial cells containing numerous vesiculo-vacuolar organelles; and infiltrates of neutrophils and eosinophils. Our findings illustrate that overexpression of the IL-4 gene in vivo can result in eyelid lesions associated with piecemeal degranulation of mast cells, as well as tissue fibrosis and a variety of other pathologic changes. These results also represent the first direct morphologic evidence for histamine secretion by mast cells in vivo.  相似文献   
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From March to August 1984, 26 patients with hereditary hemolytic anemia in northeastern Ohio developed acute, profound red cell aplasia. The patients included 14 males and 12 females 2 to 23 years old, with sickle cell anemia (20 cases), hemoglobin SC-disease (4 cases), sickle- beta-thalassemia (1 case), or hereditary spherocytosis (1 case). All had an acute onset of severe reticulocytopenia and anemia and prodromal symptoms of illness including fever, abdominal symptoms, headache, and arthralgias. Twenty-two received transfusions. Reticulocytosis occurred spontaneously within 2 to 14 days of presentation. In five acute-phase sera, 10(8) to 10(12) viral particles/mL were detected by electron microscopy. Human parvovirus B19 DNA was demonstrated in high concentration by hybridization in the same five acute-phase sera and in low concentration in sera of eight additional patients. The five highly viremic sera inhibited erythroid colony formation in vitro. B19- specific IgM was detected in sera of 24/26 patients, and B19-specific IgG in 21 of 22 patients tested. Our results indicate that human parvovirus B19 was the etiologic agent in this large epidemic of life- threatening acute red cell aplasia in patients with hereditary hemolytic anemia.  相似文献   
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The spectrum of the Guillain-Barre Syndrome (GBS) has recently been widened by the newly identified forms of acute motor axonal neuropathy (AMAN) and acute motor sensory axonal neuropathy (AMSAN). An important question has been raised regarding the possibility for the axon to be a target in immune-mediated damage. Although myelin breakdown is the characteristic feature of classic acute inflammatory demyelinating polyradiculoneuropathy (AIDP), axonal degeneration may occasionally be observed in this form, especially in cases with explosive onset and severe clinical course. Immunohistochemical findings of five frozen sural nerves biopsies of patients with GBS (AIDP variant) tested with a panel of monoclonal antibodies raised against different molecules implicated in immune-mediated processes have principally disclosed an immunoreactivity of tumor necrosis factor-alpha (TNF-alpha) on both Schwann cell membranes and in myelinated and unmyelinated axons. On the other hand, interleukin 1-beta (IL1-beta) labeled Schwann cells, endothelial cells and macrophages; interferon-gamma (IFN-gamma) was observed both in endothelial cells and lymphocytes. Membrane attack complex (C5b-9) deposits were observed on Schwann cell membranes and finally intercellular adhesion molecule-1 (ICAM-1) was localized both on endothelial cells and macrophages. Our findings strongly suggest that TNF-alpha is an important factor in the cascade of events leading to immune-mediated demyelination and axonal damage in GBS.  相似文献   
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BackgroundMen who have sex with men are a risk group for anal human papillomavirus (HPV) and anal cancer. Australia introduced a universal school-based HPV vaccination program in 2013. Self-reported HPV vaccination status has been widely used in clinical and research settings, but its accuracy is understudied.ObjectiveWe aimed to examine the accuracy of self-reported HPV vaccination status among gay and bisexual adolescent males.MethodsWe included 192 gay and bisexual males aged 16-20 years from the Human Papillomavirus in Young People Epidemiological Research 2 (HYPER2) study in Melbourne, Australia. All participants had been eligible for the universal school-based HPV vaccination program implemented in 2013 and were asked to self-report their HPV vaccination status. Written informed consent was obtained to verify their HPV vaccination status using records at the National HPV Vaccination Program Register and the Australian Immunisation Register. We calculated the sensitivity, specificity, positive predictive value, and negative predictive value of self-reported HPV vaccination status.ResultsThe median age of the 192 males was 19 (IQR 18-20) years. There were 128 males (67%) who had HPV vaccination records documented on either registry. Self-reported HPV vaccination had a sensitivity of 47.7% (95% CI 38.8%-56.7%; 61/128), a specificity of 85.9% (95% CI 75.0%-93.4%; 55/64), a positive predictive value of 87.1% (95% CI 77.0%-93.9%; 61/70), and a negative predictive value of 45.1% (95% CI 36.1%-54.3%; 55/122).ConclusionsSelf-reported HPV vaccination status among Australian gay and bisexual adolescent males underestimates actual vaccination and may be inaccurate for clinical and research purposes.  相似文献   
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Although amebic liver abscess can virtually always be successfully treated medically, percutaneous drainage has been advocated recently. In 96 recently treated patients, therapeutic aspiration and percutaneous drainage were rarely needed. Most cases were correctly diagnosed by means of clinical, laboratory, and sonographic findings. Abscesses in only 13 (13.5%) patients were diagnostically aspirated. An abscess in one patient was therapeutically aspirated because the patient was responding slowly to medical therapy. No patient required catheter drainage. The key to successful amebic abscess management is medical therapy. Therapeutic drainage is rarely needed. Successfully treated patients occasionally respond slowly to medical therapy, and successfully treated amebic abscesses may enlarge or become bizarre-appearing on sonograms. This should not prompt therapeutic drainage. Diagnostic aspiration is appropriate when amebic and pyogenic abscesses are indistinguishable using clinical and imaging findings. Rare indications for therapeutic aspiration or drainage include pyogenic superinfection and large, juxtacardiac abscesses (potential intrapericardial rupture).  相似文献   
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BACKGROUND: Triplet regimens were occasionally reported to produce a higher response rate (RR) than doublets in locally advanced or metastatic non-small-cell lung cancer (NSCLC). This trial was conducted to assess (i) whether the addition of cisplatin (CDDP) to either gemcitabine (GEM) and vinorelbine (VNR) or GEM and paclitaxel (PTX) significantly prolongs overall survival (OS) and (ii) to compare the toxicity of PTX-containing and VNR-containing combinations. PATIENTS AND METHODS: Stage III or IV NSCLC patients were randomly assigned to (i) GEM 1000 mg/m(2) and VNR 25 mg/m(2) on days 1 and 8 (GV arm); (ii) GEM 1000 mg/m(2) and PTX 125 mg/m(2) on days 1 and 8 (GT arm); (iii) GV plus CDDP 50 mg/m(2) on days 1 and 8 (PGV arm); and (iv) GT plus CDDP 50 mg/m(2) on days 1 and 8 (PGT arm). Treatments were repeated every 3 weeks for a maximum of six cycles. RESULTS: A total of 433 (stage III, 160; stage IV, 273) patients were randomly allocated to the study. RR was 48% [95% confidence interval (CI), 42% to 54%] for triplets and 35% (95% CI, 32% to 38%) for doublets (P = 0.004). Median progression-free survival (6.1 versus 5.5 months, P = 0.706) and median OS (10.7 versus 10.5 months, P = 0.379) were similar. CDDP significantly increased the occurrence of severe neutropenia (35% versus 13%), thrombocytopenia (14% versus 4%), anaemia (9% versus 3%), vomiting (6% versus 0.5%), and diarrhoea (6% versus 2%). Conversely, frequency of severe neutropenia (30% versus 17%) and thrombocytopenia (11% versus 6%) was significantly higher with VNR-containing regimens. CONCLUSIONS: Adding CDDP to GV or GT significantly increased RR, but did not prolong the OS of patients. Among doublets, the GT regimen should be preferred in view of its better safety profile.  相似文献   
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