7 resultados para Restricted dissimilarity function

em DI-fusion - The institutional repository of Université Libre de Bruxelles


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Recent evidence suggests that in addition to their well known stimulatory properties, dendritic cells (DCs) may play a major role in peripheral tolerance. It is still unclear whether a distinct subtype or activation status of DC exists that promotes the differentiation of suppressor rather than effector T cells from naive precursors. In this work, we tested whether the naturally occurring CD4+ CD25+ regulatory T cells (Treg) may control immune responses induced by DCs in vivo. We characterized the immune response induced by adoptive transfer of antigen-pulsed mature DCs into mice depleted or not of CD25+ cells. We found that the development of major histocompatibility complex class I and II-restricted interferon gamma-producing cells was consistently enhanced in the absence of Treg. By contrast, T helper cell (Th)2 priming was down-regulated in the same conditions. This regulation was independent of interleukin 10 production by DCs. Of note, splenic DCs incubated in vitro with Toll-like receptor ligands (lipopolysaccharide or CpG) activated immune responses that remained sensitive to Treg function. Our data further show that mature DCs induced higher cytotoxic activity in CD25-depleted recipients as compared with untreated hosts. We conclude that Treg naturally exert a negative feedback mechanism on Th1-type responses induced by mature DCs in vivo.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The elderly population has been neglected by the traditional approach to clinical breast cancer research. Elderly women have been underrepresented in breast cancer clinical trials, with the majority of studies being restricted to patients aged < 70 years. Elderly patients frequently have comorbidities and/or impaired organ function. These facts may often lead to death from causes other than cancer, thus nullifying any possible benefit of adjuvant treatment; furthermore, they render extrapolation of standard treatment recommendations to the elderly potentially hazardous, particularly with respect to chemotherapy. Therefore, specific clinical trials are needed to investigate adjuvant treatments tailored for the heterogeneous older population.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Treatment regimens for solid tumours have been extensively investigated for their physical toxic effects, but far less is known about the potential impairment of cognitive function by anticancer treatment regimens. Here, we review published studies that examined cognitive function in adult patients receiving systemic therapy for solid tumours. Our review suggests that patients can experience cognitive changes related to their treatment. However, several studies had methodological limitations, such as use of a limited sample size, lack of baseline assessment, and lack of control for potential confounding factors. Better designed clinical trials are required so that the difficulties patients face in terms of reduced cognitive function as a result of anticancer treatment can be fully elucidated. These trials should have sufficient statistical power and, importantly, should also be prospective.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Novel immune-type receptors (NITRs) are encoded by large multi-gene families and share structural and signaling similarities to mammalian natural killer receptors (NKRs). NITRs have been identified in multiple bony fish species, including zebrafish, and may be restricted to this large taxonomic group. Thirty-nine NITR genes that can be classified into 14 families are encoded on zebrafish chromosomes 7 and 14. Herein, we demonstrate the expression of multiple NITR genes in the zebrafish ovary and during embryogenesis. All 14 families of zebrafish NITRs are expressed in hematopoietic kidney, spleen and intestine as are immunoglobulin and T cell antigen receptors. Furthermore, all 14 families of NITRs are shown to be expressed in the lymphocyte lineage, but not in the myeloid lineage, consistent with the hypothesis that NITRs function as NKRs. Sequence analyses of NITR amplicons identify known alleles and reveal additional alleles within the nitr1, nitr2, nitr3, and nitr5 families, reflecting the recent evolution of this gene family.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Background. In clinical practice and in clinical trials, echocardiography and scintigraphy are used the most for the evaluation of global left ejection fraction (LVEF) and left ventricular (LV) volumes. Actually, poor quality imaging and geometrical assumptions are the main limitations of LVEF measured by echocardiography. Contrast agents and 3D echocardiography are new methods that may alleviate these potential limitations. Methods. Therefore we sought to examine the accuracy of contrast 3D echocardiography for the evaluation of LV volumes and LVEF relative to MIBI gated SPECT as an independent reference. In 43 patients addressed for chest pain, contrast 3D echocardiography (RT3DE) and MIBI gated SPECT were prospectively performed on the same day. The accuracy and the variability of LV volumes and LVEF measurements were evaluated. Results. Due to good endocardial delineation, LV volumes and LVEF measurements by contrast RT3DE were feasible in 99% of the patients. The mean LV end-diastolic volume (LVEDV) of the group by scintigraphy was 143 65 mL and was underestimated by triplane contrast RT3DE (128 60 mL; p < 0.001) and less by full-volume contrast RT3DE (132 62 mL; p < 0.001). Limits of agreement with scintigraphy were similar for triplane andfull-volume, modalities with the best results for full-volume. Results were similar for calculation of LV end-systolic volume (LVESV). The mean LVEF was 44 16% with scintigraphy and was not significantly different with both triplane contrast RT3DE (45 15%) and full-volume contrast RT3DE (45 15%). There was an excellent correlation between two different observers for LVEDV, LVESV and LVEF measurements and inter observer agreement was also good for both contrast RT3DE techniques. Conclusion. Contrast RT3DE allows an accurate assessment of LVEF compared to the LVEF measured by SPECT, and shows low variability between observers. Although RT3DE triplane provides accurate evaluation of left ventricular function, RT3DE full-volume is superior to triplane modality in patients with suspected coronary artery disease. © 2009 Cosyns et al; licensee BioMed Central Ltd.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

For pt.I see ibid. vol.3, p.195 (1987). The authors have shown that the resolution of a confocal scanning microscope can be improved by recording the full image at each scanning point and then inverting the data. These analyses were restricted to the case of coherent illumination. They investigate, along similar lines, the incoherent case, which applies to fluorescence microscopy. They investigate the one-dimensional and two-dimensional square-pupil problems and they prove, by means of numerical computations of the singular value spectrum and of the impulse response function, that for a signal-to-noise ratio of, say 10%, it is possible to obtain an improvement of approximately 60% in resolution with respect to the conventional incoherent light confocal microscope. This represents a working bandwidth of 3.5 times the Rayleigh limit.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Cryopreservation of ovarian tissue has been proposed for storing gametes of young patients at high risk of premature ovarian failure. Autotransplantation has recently provided some promising results and is still the unique option to restore ovarian function from cryopreserved ovarian tissue in humans. In this article, we analyse data from the combined orthotopic and heterotopic transplantation of cryopreserved ovarian tissue that restored the ovarian function and fertility. Orthotopic transplantation of cryopreserved ovarian tissue at ovarian and peritoneal sites, together with a heterotopic transplantation at the abdominal subcutaneous site, was performed to restore the ovarian function of a 29-year-old woman previously treated with bone marrow transplantation (BMT) for Hodgkin's disease. Ovarian reserve markers progressively suppress within values 5 months after the transplantation (basal FSH 5 mUI/ml and inhibin B 119 ng/ml). Follicular development was observed at all transplantation sites but was predominant at the ovarian site. Six natural cycles were fully documented and analysed. The patient became spontaneously pregnant following the sixth cycle, but unfortunately she later miscarried. Combined orthotopic and heterotopic transplantations succeeded in the restoration of normal spontaneous cycles. Furthermore, this spontaneous pregnancy confirmed the efficiency of this procedure for restoring human fertility.