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Primary breast diffuse large B‐cell lymphoma (DLBCL) is a rare subtype of non‐Hodgkin lymphoma (NHL) with limited data on pathology and outcome. A multicentre retrospective study was undertaken to determine prognostic factors and the incidence of central nervous system (CNS) relapses. Data was retrospectively collected on patients from 8 US academic centres. Only patients with stage I/II disease (involvement of breast and localized lymph nodes) were included. Histologies apart from primary DLBCL were excluded. Between 1992 and 2012, 76 patients met the eligibility criteria. Most patients (86%) received chemotherapy, and 69% received immunochemotherapy with rituximab; 65% received radiation therapy and 9% received prophylactic CNS chemotherapy. After a median follow‐up of 4·5 years (range 0·6–20·6 years), the Kaplan–Meier estimated median progression‐free survival was 10·4 years (95% confidence interval [CI] 5·8–14·9 years), and the median overall survival was 14·6 years (95% CI 10·2–19 years). Twelve patients (16%) had CNS relapse. A low stage‐modified International Prognostic Index (IPI) was associated with longer overall survival. Rituximab use was not associated with a survival advantage. Primary breast DLBCL has a high rate of CNS relapse. The stage‐modified IPI score is associated with survival.  相似文献   
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Diffuse large B‐cell lymphoma (DLBCL) occasionally presents with circulating malignant cells. The clinical characteristics and long‐term outcomes of these patients have not been described. Twenty‐nine newly diagnosed DLBCL presenting in leukaemic phase were identified between 1996 and 2010, at two institutions. Median age was 48 years, and patients presented with leucocytosis, high lactate dehydrogenase levels, B symptoms, and high International Prognostic Index score. Extra nodal site involvement was observed in all patients and affected the bone marrow (100%), spleen (62%), pleura/lung (41%), liver (21%), bone (17%), bowels (7%) and cerebrospinal fluid (14%). Blood lymphomatous cells co‐expressed CD19, CD20, CD22, CD38, CD45, HLA‐DR and FMC7 in >90%, and kappa or lambda light chain restriction in >50%. Ninety per cent received rituximab and anthracycline‐based chemotherapy. Overall, remission was complete in 54% and partial in 31%; 15% had resistant disease. Median follow‐up was 47 months; 13 (45%) patients remain alive in complete remission. Median progression‐free and overall survivals were 11·5 and 46·7 months, respectively. In summary, patients with DLBCL in leukaemic phase present with high tumour burden and frequent involvement of extra nodal sites. In this uncommon DLBCL subgroup, anthracycline‐based regimens with rituximab are associated with early morbidity and mortality, but yield approximately 50% 4‐year survival.  相似文献   
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Purpose: Rasmussen encephalitis (RE) leads to progressive tissue and function loss of one brain hemisphere and often intractable epilepsy. This is the first randomized prospective treatment trial in RE. Methods: Germany‐wide, patients with suspected recent‐onset RE were recruited and if eligible randomized to tacrolimus or intravenous immunoglobulins (IVIGs). A loss of motor function or hemispheric volume by ≥15% (in patients >12 years at disease onset: ≥8%) led to study exit. Untreated patients served as a historical control group. Key Findings: Over 6.3 years, 21 patients with recent‐onset RE were identified. Sixteen were randomized to tacrolimus (n = 9) or IVIG (n = 7). Immunotreated patients had a longer “survival” than the historical controls. Neither treatment was more efficacious than the other. Two tacrolimus patients experienced serious adverse events. No immunotreated but several untreated patients developed intractable epilepsy. No patient with refractory epilepsy became treatment‐responsive under immunotherapy. Significance: The countrywide incidence rate of diagnosed RE is estimated as 2.4 cases/107 people ≤ age 18/year. Treatment with tacrolimus or IVIG may slow down tissue and function loss and prevent development of intractable epilepsy. However, immunotherapy may “arrest” patients in a dilemma state of pharmacoresistant epilepsy but too good function to be offered functional hemispherectomy. These compounds may therefore contribute to the therapeutic armamentarium for RE patients without difficult‐to‐treat epilepsies.  相似文献   
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Streptococcus pyogenes is a ubiquitous and versatile pathogen that causes a variety of infections with a wide range of severity. The versatility of this organism is due in part to its capacity to regulate virulence gene expression in response to the many environments that it encounters during an infection. We analyzed the expression of two potential virulence factors, sagA and siaA (also referred to as pel and htsA, respectively), in response to conditions of varying cell densities and iron concentrations. The sagA gene was up-regulated in conditioned medium from a wild-type strain but not from sagA-deficient mutants, and the gene was also up-regulated in the presence of streptolysin S (SLS), the gene product of sagA, thus indicating that this gene or its product is involved in density-dependent regulation of S. pyogenes. By comparison, siaA responded in a manner consistent with a role in iron acquisition since it was up-regulated under iron-restricted conditions. Although siaA expression was also up-regulated in the presence of SLS and in conditioned media from both wild-type and sagA-deficient mutants, this up-regulation was not growth phase dependent. We conclude that sagA encodes a quorum-sensing signaling molecule, likely SLS, and further support the notion that siaA is likely involved in iron acquisition.  相似文献   
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There is increasing concern about the toxicity of inhaled multi-walled carbon nanotubes (MWCNTs). Pulmonary macrophages represent the primary cell type involved in the clearance of inhaled particulate materials, and induction of apoptosis in these cells has been considered to contribute to the development of lung fibrosis. We have investigated the apoptotic, inflammogenic, and fibrogenic potential of two types of MWCNTs, characterised by a contrasting average tube length and entanglement/agglomeration. Both nanotube types triggered H2O2 formation by RAW 264.7 macrophages, but in vitro toxicity was exclusively seen with the longer MWCNT. Both types of nanotubes caused granuloma in the mouse lungs. However, the long MWCNT induced a more pronounced pro-fibrotic (mRNA expression of matrix metalloproteinase-8 and tissue inhibitor of metalloproteinase-1) and inflammatory (serum level of monocyte chemotactic protein-1) response. Masson trichrome staining also revealed epithelial cell hyperplasia for this type of MWCNT. Enhanced apoptosis was detected by cleaved caspase 3 immunohistochemistry in lungs of mice treated with the long and rigid MWCNT and, to a lesser extent, with the shorter, highly agglomerated MWCNT. However, staining was merely localised to granulomatous foci, and neither of the MWCNTs induced apoptosis in vitro, evaluated by caspase 3/7 activity in RAW 264.7 cells. In addition, our study reveals that the inflammatory and pro-fibrotic effects of MWCNTs in the mouse lung can vary considerably depending on their composition. The in vitro analysis of macrophage apoptosis appears to be a poor predictor of their pulmonary hazard.  相似文献   
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