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41.
This study reports on the immunocytochemical localization of tumor necrosis factor-alpha (TNFα) in immune-mediated demyelination and Wallerian degeneration of the rat peripheral nervous system (PNS) using teased nerve fiber preparations. In experimental autoimmune neuritis induced by active immunization (EAN) or by adoptive transfer of autoreactive T cells (AT-EAN), macrophages passing blood vessels as well as macrophages adherent to nerve fibers were TNFα-positive. Large post-phagocytic macrophages at later stages of demyelination were TNFα-negative. Intraperitoneal application of an anti-TNFα antibody to EAN rats significantly reduced the degree of inflammatory demyelination, suggesting a pathogenic role for TNFα. After nerve transection only macrophages located within degenerating nerve fibers were TNFα-positive, while those entering and leaving nerves were negative. TNFα produced by macrophages seems to bevolved in immune-mediated demyelination and non-immune myelin degradation after axotomy. While interferon-gamma (IFNγ) is present in EAN nerves and may act as a local stimulus for TNF expression, the nature of this signal in Wallerian degeneration in the absence of IFNγ is unknown.  相似文献   
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Background

Permanent low-dose-rate brachytherapy (BT) with iodine 125 is an established curative treatment for localized prostate cancer. After treatment, prostate-specific antigen (PSA) kinetics may show a transient rise (PSA bounce). Our aim was to investigate the association of PSA bounce with biochemical control.

Patients and methods

Patients treated with BT in Switzerland were registered in a prospective database. Only patients with a follow-up of at least 2 years were included in our analysis. Clinical follow-up and PSA measurements were assessed after 1.5, 3, 6, and 12 months, and annually thereafter. If PSA increased, additional follow-up visits were scheduled. Cases of PSA bounce were defined as a rise of at least 0.2 ng/ml above the initial PSA nadir with a subsequent decline to or below the initial nadir without treatment. Biochemical failure was defined as a rise to nadir +?2 ng/ml.

Results

Between March 2001 and November 2010, 713 patients with prostate cancer undergoing BT with at least 2 years of follow-up were registered. Median follow-up time was 41 months. Biochemical failure occurred in 28 patients (3.9?%). PSA bounce occurred in 173 (24.3?%) patients; only three (1.7?%) patients with PSA bounce developed biochemical failure, in contrast to 25 (4.6?%) patients without previous bounce (p?<?0.05). The median time to bounce was 12 months, the median time to biochemical failure was 30 months. The median bounce increase was 0.78 ng/ml. Twenty-eight patients with bounce (16.5?%) had a transient PSA rise of +?2 ng/ml above the nadir.

Conclusion

In most cases, an early increase in PSA after BT indicates PSA bounce and is associated with a lower risk of biochemical failure.
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The immune response to pneumococcal capsular polysaccharides (CPSs) and to the pneumococcal surface proteins cell wall-associated serine proteinase A (PrtA), pneumococcal surface protein A (PspA), and Streptococcus pneumoniae pullulanase A was evaluated in 45 patients with invasive pneumococcal disease compared with healthy adults. In serum from patients with meningitis and pneumonia, CPS antibody levels were low, compared with healthy adults; antibody levels did not differ between groups and did not change between phases. Levels of immunoglobulin G directed against the investigated pneumococcal surface proteins in patients with invasive pneumococcal disease were in the same range as in healthy adults. However, median PrtA and PspA antibody levels tended to increase during early convalescent phase. Low levels of CPS antibody, rather than of antibodies directed against the pneumococcal surface proteins, may predispose to invasive pneumococcal infection.  相似文献   
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Eosinophilia is frequently detectable in certain myeloid neoplasms and various reactive conditions, but it may also occur in the absence of an apparent underlying disease, or, rarely, as a paraneoplastic feature with solid tumors. In myeloid neoplasms, eosinophils are considered to belong to the malignant clone in most cases, whereas in all other conditions, eosinophilia is a reactive process triggered by eosinopoietic cytokines. Excessive accumulation of eosinophils, also termed hypereosinophilia (HE), is typically seen in eosinophilic leukemias, but it may also occur in other neoplasms and reactive disorders. HE-related end organ damage may develop in patients with reactive HE but also in those with hematologic malignancies. During the past few years, our knowledge about HE and HE-related organ damage in hematologic and nonhematologic disorders has improved considerably. Moreover, proposals for the definition and classification of eosinophil disorders have been generated by various expert groups and by the World Health Organization (WHO). However, several questions related to eosinophils and HE remain open, and many aspects of the definition and classification of eosinophil disorders and related pathologies remain controversial. In the current article, these open issues are discussed with special reference to the 2008 WHO classification of myeloid neoplasms and other classifications proposed by immunologists and various expert panels, as well as definitions and criteria recently proposed in a multidisciplinary consensus proposal.  相似文献   
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