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61.
62.
BACKGROUND AND OBJECTIVES: The objective of improving the quality of responses of chronic lymphocytic leukemia (CLL) patients has led to the design of protocols that combine fludarabine (FDR) with synergistic drugs. We evaluated the efficacy and toxicity of a schedule that includes fludarabine, ara-C, novantrone and dexamethasone (FAND) for the management of previously treated CLL patients under 60 years old. DESIGN AND METHODS: Thirty-one patients underwent FAND treatment. Twenty-three patients had active disease (relapsed patients: 9; unresponsive to prior therapy: 14). Eight patients had a partial response (PR) to prior therapy and were treated with the aim of further reducing residual disease. The FAND schedule included fludarabine (25 mg/m(2) i.v. days 1-3), ara-C (1 g/m(2) i.v. day 1: 8 patients; days 1-2: 23 patients), novantrone (10 mg/m(2) i.v. day 1) and dexamethasone (20 mg i.v. days 1-3). Infection prophylaxis consisted of fluconazole, acyclovir, trimethoprim/sulfamethoxasole and granulocyte colony-stimulating factor (G-CSF) in the presence of severe neutropenia. RESULTS: A response was observed in 7/14 refractory patients (complete response-CR: 29%), in all 9 relapsed patients (CR: 78%) and in 7/8 patients (CR: 87.5%) treated in PR. Taken together, 18 CRs were obtained and in 14 (78%) this was associated with a flow cytometric remission (CD5+/CD20(weak+) PB lymphocytes: <10%). Severe granulocytopenia occurred after 86 of the 124 administered courses (69%), but only after 10/86 courses (12%) were major infections recorded. In 10/15 mobilized patients (cyclophosphamide + G-CSF: 6 patients; FAND + G-CSF: 9 patients) after FAND > or = 2 x 10(6)/kg CD34+ cells were collected. Nine patients were autografted in CR and showed a longer response duration than the 9 patients in CR who did not receive further therapy after FAND (53 vs 30% at 41 months; p = 0.05). INTERPRETATION AND CONCLUSIONS: FAND associated with extensive infection prophylaxis and G-CSF support is a highly cytoreductive and well-tolerated treatment for CLL patients and in most cases does not hamper subsequent stem cell mobilization.  相似文献   
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64.
Human leucocyte antigen (HLA)-C molecules regulate the function of natural killer cells and may be subdivided into two groups, C(1) and C(2), based on their specificity for inhibitory killer immunoglobulin-like receptors. We analysed the impact of the HLA-C genotype on outcome of HLA-C-matched unrelated donor haematopoietic stem cell transplantation (URD-HSCT) recipients. HLA-C(2) homozygous patients (n = 18) had lower probability of overall survival (P = 0.01) and disease-free survival (P = 0.02), resulting from increased relapse rate (P = 0.02) when compared with both HLA-C(1) homozygous (n = 43) and HLA-C(1),C(2) heterozygous (n = 50) subgroups. Patients lacking HLA-C(1) should, therefore, be considered at increased risk of relapse following HLA-C-matched URD-HSCT.  相似文献   
65.

Objectives

Systemic sclerosis (SSc) causes functional and structural microcirculatory dysfunction, affecting also distal extremities. Optical Near-InfraRed Spectroscopy (NIRS) of blood HbO2 saturation (stO2) is able to evaluate O2 delivery/consumption balance in the explored tissue. The NIRS-sensitive camera non-invasively detects stO2 values in superficial tissues, automatically generating 2D-imaging maps in real time. We aimed at testing whether NIRS hand imaging may evaluate peripheral microcirculatory dysfunction and its spatial heterogeneity in SSc patients compared to controls.

Methods

Forty SSc patients (aged 55.1?±?15.6 years) and twenty-one healthy controls (aged 54.3?±?14.5years, p?=?0.89) were studied by palmar hand NIRS-2D imaging. A blood pressure cuff was applied to the forearm and 3 min ischemia was induced. Images were acquired at basal conditions and every 10 seconds during 3 minutes of ischemia and 5 minutes of reperfusion. Five regions of interest were positioned on each fingertip, from the second to the fifth finger and one on the thenar eminence.

Results

A significant difference was found between controls and SSc patients in basal stO2 (84.3?±?7.5?vs. 75.4?±?10.9%, p?<?0.001), minimum stO2 (65.2?±?8.0?vs. 53.4?±?10.1%, p?<?0.001) and time to maximum stO2 during hyperemia (63?±?38?vs. 85?±?49?s, p?<?0.05). Among clinical characteristics, anti-Scl70 antibody positivity, digital ulcers history and smoke exposure affected NIRS parameters, as well as sildenafil and statins therapy. Conversely, no significant differences were found in NIRS-2D values between different nailfold-videocapillaroscopy patterns.

Conclusion

NIRS-2D imaging is a simple, automated tool to non-invasively detect regional microcirculatory impairment in SSc, which seems to add significant functional information to the morphological picture of nailfold-videocapillaroscopy.  相似文献   
66.
B lymphocytes and epithelial cells are the only cell types known to be infected with Epstein-Barr virus (EBV) in normal individuals. Rarely, EBV also infects other cells, including natural killer (NK) cells, almost always in the context of fatal leukaemias or lymphoproliferative disorders. We report on a 6-year-old previously healthy girl who developed fevers and liver function abnormalities for 3 months. The peripheral blood revealed an abnormal expansion of large granular lymphocytes, comprising 24% of the white blood cells. Flow cytometric analysis of the peripheral blood mononuclear cells showed an abnormal increase of CD16-positive NK cells, 62% of which were EBV-infected by in situ EBER-1 hybridization. The circulating B cells were normal in number, but 18% were infected with EBV by in situ EBER-1 hybridization. Approximately 2 years after resolution of all symptoms and continued good health, 35% of the circulating mononuclear cells were EBV-infected, indicative of persistent expansion of EBV-infected cells. We conclude that abnormal expansions of EBV-infected NK and B cells can be associated with a chronic benign course.  相似文献   
67.
68.
Reliable chemical sensors with high selectivity and sensitivity toward specific target molecules require rational synthesis of receptors, in-depth characterization of their complexation abilities and highly efficient transduction of the molecular recognition event. Here we report a steady-state and time-resolved fluorescence investigation of EtQxBox, a fluorescent conformationally blocked quinoxaline-based cavitand, aimed at assessing its selectivity toward aromatic versus non-aromatic analytes in solution. Fluorescence quenching of the EtQxBox in acetone is observed at increasing concentration of both aromatic (i.e. benzonitrile) and aliphatic (i.e. acetonitrile) compounds. The combination with fluorescence lifetime measurements permits to discriminate the predominantly static quenching of the aromatic analyte, due to non-fluorescent host–guest complex formation, from the mostly dynamic quenching of the non-aromatic compound, resulting from aspecific diffusive collisions between the fluorophore and the quencher. The equilibrium association constants for both the complexes have been estimated using Stern–Volmer model.

We investigate the role of combined static and dynamic quenching in fluorescence transduction of benzonitrile and acetonitrile complexation by a rigid quinoxaline-based cavitand.  相似文献   
69.
Journal of Thrombosis and Thrombolysis - To compare age at 1st ischaemic stroke (IS) in a cohort of juvenile (&lt;?46&nbsp;years of age) IS patients evaluated for the rs1801133...  相似文献   
70.
Since the dawn of medicine, scientists have carefully observed, modeled and interpreted the human body to improve healthcare. At the beginning there were drawings and paintings, now there is three-dimensional modeling. Moving from two-dimensional cultures and towards complex and relevant biomaterials, tissue-engineering approaches have been developed in order to create three-dimensional functional mimics of native organs. The bone marrow represents a challenging organ to reproduce because of its structure and composition that confer it unique biochemical and mechanical features to control hematopoiesis. Reproducing the human bone marrow niche is instrumental to answer the growing demand for human erythrocytes and platelets for fundamental studies and clinical applications in transfusion medicine. In this review, we discuss the latest culture techniques and technological approaches to obtain functional platelets and erythrocytes ex vivo. This is a rapidly evolving field that will define the future of targeted therapies for thrombocytopenia and anemia, but also a long-term promise for new approaches to the understanding and cure of hematologic diseases.  相似文献   
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