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OBJECTIVE: To describe epidemiological, clinical, and immunological characteristics and the longterm course of persistent mixed cryoglobulinemia (MC) in patients infected with hepatitis C virus (HCV). METHODS: Retrospective study of HCV infected patients (HCV RNA positive) who had persistent positive MC, with 2 immunochemical typings of MC carried out after 24-month minimum interval. RESULTS: In total, 125 patients were studied, aged 52 +/- 13 years at diagnosis of MC, with duration of HCV infection of 18 +/- 10 years. At entry, 60 patients had type II MC, 53 patients had type III, and 12 patients had the oligoclonal type. At the second immunochemical typing, after a mean interval of 45 +/- 20 months, MC was type II in 72 patients, type III in 39 patients, and the oligoclonal type in 14 patients. The proportion of cases of MC with the same immunochemical type was higher among patients with type II (78%) than type III (59%) or oligoclonal MC (17%) (p < 0.01). The MC that changed turned more to type II (55.5%) than type III (29%) or the oligoclonal type (15.5%) (p = 0.0002). MC vasculitis (purpura, arthralgia, peripheral neuropathy, renal involvement) and other extrahepatic manifestations (polyarteritis nodosa, lymphoma) in 60/125 patients was associated with advanced age (p < 0.01), a longer duration of infection (p < 0.05), type II MC (odds ratio = 5, p < 0.01), and a higher MC serum level (p < 0.01). CONCLUSION: During chronic active HCV infection, type II MC is more stable over time than type III and oligoclonal MC. The oligoclonal type appears to be an intermediate stage in the course of type III changing to type II MC. Symptomatic persistent HCV MC was associated with advanced age, longer duration of HCV infection, type II MC, and a higher MC serum level.  相似文献   
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A large, multicentre, retrospective survey of patients with hairy cell leukaemia (HCL) was conducted in France to determine the frequency of second malignancies and to analyse the long‐term effects of the established purine nucleoside analogues (PNAs), cladribine and pentostatin. The survey retrospectively reviewed the medical history of patients and their immediate family, clinical and biological presentation at the time of HCL diagnosis, treatment choice, response to treatment, time to relapse and cause of death. Data were collected for 487 patients with HCL. Of the patients included in the survey, 18% (88/487) had a familial history of cancers, 8% (41/487) presented with malignancies before HCL diagnosis and 10% (48/487) developed second malignancies after HCL was diagnosed. An excess incidence of second malignancies was observed, with a standardized incidence ratio (SIR) of 1·86 (95% confidence interval (CI): 1·34–2·51), with no significant difference between PNAs. For second haematological malignancies alone, the SIR was markedly increased at 5·32 (95% CI: 2·90–8·92). This study highlights the high frequency of cancers in HCL patients and their family members. The frequency of second malignancies is notably increased, particularly for haematological malignancies. The respective role of pentostatin and cladribine in the development of second malignancies is debatable.  相似文献   
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Background

We recently assigned a new fibrinolytic function to cell-derived microparticles in vitro. In this study we explored the relevance of this novel property of microparticles to the in vivo situation.

Design and Methods

Circulating microparticles were isolated from the plasma of patients with thrombotic thrombocytopenic purpura or cardiovascular disease and from healthy subjects. Microparticles were also obtained from purified human blood cell subpopulations. The plasminogen activators on microparticles were identified by flow cytometry and enzyme-linked immunosorbent assays; their capacity to generate plasmin was quantified with a chromogenic assay and their fibrinolytic activity was determined by zymography.

Results

Circulating microparticles isolated from patients generate a range of plasmin activity at their surface. This property was related to a variable content of urokinase-type plasminogen activator and/or tissue plasminogen activator. Using distinct microparticle subpopulations, we demonstrated that plasmin is generated on endothelial and leukocyte microparticles, but not on microparticles of platelet or erythrocyte origin. Leukocyte-derived microparticles bear urokinase-type plasminogen activator and its receptor whereas endothelial microparticles carry tissue plasminogen activator and tissue plasminogen activator/inhibitor complexes.

Conclusions

Endothelial and leukocyte microparticles, bearing respectively tissue plasminogen activator or urokinase-type plasminogen activator, support a part of the fibrinolytic activity in the circulation which is modulated in pathological settings. Awareness of this blood-borne fibrinolytic activity conveyed by microparticles provides a more comprehensive view of the role of microparticles in the hemostatic equilibrium.Key words: fibrinolytic microparticles, plasmin, plasminogen, uPA, tPA  相似文献   
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We report the case of a 33-year-old pregnant woman. The third-trimester ultrasound scan during pregnancy revealed fetal bilateral ventricular dilatation, macrosomia and a transverse diameter of the cerebellum at the 30th centile. A brain MRI scan at 31 weeks of gestation led to a diagnosis of hypoplasia of the cerebellar vermis without hemisphere abnormalities and a non compressive expansion of the cisterna magna. The fetal karyotype was 46,XX. The pregnancy was terminated and array-CGH analysis of the fetus identified a 238 kb de novo deletion on chromosome Xp12, encompassing part of OPHN1 gene. Further studies revealed a completely skewed pattern of X inactivation. OPHN1 is involved in X-linked mental retardation (XLMR) with cerebellar hypoplasia and encodes a Rho-GTPase-activating protein called oligophrenin-1, which is produced throughout the developing mouse brain and in the hippocampus and Purkinje cells of the cerebellum in adult mice. Neuropathological examination of the female fetus revealed cerebellar hypoplasia and the heterotopia of Purkinje cells at multiple sites in the white matter of the cerebellum. This condition mostly affects male fetuses in humans. We report here the first case of a de novo partial deletion of OPHN1, with radiological and neuropathological examination, in a female fetus.  相似文献   
58.

Objectives

The association between periodontal disease and adverse pregnancy outcomes (APO), primarily preterm birth (PTB), is still controversially discussed in the literature. Therefore, the aim of the present systematic review was to analyze the existing literature on the potential association between inflammatory mediators detected in gingival crevicular fluid (GCF) and APO.

Materials and methods

MEDLINE (PubMed) and EMBASE databases were searched for entries up to April 2012 and studies were selected by two independent reviewers.

Results

The majority of the eight studies included confirmed a positive association between GCF mediators, such as interleukin-1β, prostaglandin E2, and tumor necrosis factor-alpha, and APO. Due to the heterogeneity and variability of the available studies, no meta-analysis could be performed.

Conclusions

A positive association between GCF inflammatory mediator levels and APO/PTB might be present but the results need to be considered with great caution because of the heterogeneity and variability among the studies. Further studies with an adequate number of patients allowing for an appropriate analysis are warranted to definitely confirm this association.

Clinical relevance

The present findings suggest that an association between GCF inflammatory mediator levels and APO might exist.  相似文献   
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