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1.
Oncoimmunology ; 6(2): e1216291, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28344861

RESUMO

We demonstrated that γδ T cells of patients given HLA-haploidentical HSCT after removal of αß+ T cells and CD19+ B cells are endowed with the capacity of killing leukemia cells after ex vivo treatment with zoledronic acid (ZOL). Thus, we tested the hypothesis that infusion of ZOL in patients receiving this type of graft may enhance γδ T-cell cytotoxic activity against leukemia cells. ZOL was infused every 28 d in 43 patients; most were treated at least twice. γδ T cells before and after ZOL treatments were studied in 33 of these 43 patients, till at least 7 mo after HSCT by high-resolution mass spectrometry, flow-cytometry, and degranulation assay. An induction of Vδ2-cell differentiation, paralleled by increased cytotoxicity of both Vδ1 and Vδ2 cells against primary leukemia blasts was associated with ZOL treatment. Cytotoxic activity was further increased in Vδ2 cells, but not in Vδ1 lymphocytes in those patients given more than one treatment. Proteomic analysis of γδ T cells purified from patients showed upregulation of proteins involved in activation processes and immune response, paralleled by downregulation of proteins involved in proliferation. Moreover, a proteomic signature was identified for each ZOL treatment. Patients given three or more ZOL infusions had a better probability of survival in comparison to those given one or two treatments (86% vs. 54%, respectively, p = 0.008). Our data indicate that ZOL infusion in pediatric recipients of αß T- and B-cell-depleted HLA-haploidentical HSCT promotes γδ T-cell differentiation and cytotoxicity and may influence the outcome of patients.

2.
Leukemia ; 31(1): 18-25, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27416911

RESUMO

Recurrent molecular markers have been routinely used in acute myeloid leukemia (AML) for risk assessment at diagnosis, whereas their post-induction monitoring still represents a debated issue. We evaluated the prognostic value and biological impact of minimal residual disease (MRD) and of the allelic ratio (AR) of FLT3-internal-tandem duplication (ITD) in childhood AML. We retrospectively screened 494 children with de novo AML for FLT3-ITD mutation, identifying 54 harboring the mutation; 51% of them presented high ITD-AR at diagnosis and had worse event-free survival (EFS, 19.2 versus 63.5% for low ITD-AR, <0.05). Forty-one percent of children with high levels of MRD after the 1st induction course, measured by a patient-specific real-time-PCR, had worse EFS (22.2 versus 59.4% in low-MRD patients, P<0.05). Next, we correlated these parameters with gene expression, showing that patients with high ITD-AR or persistent MRD had characteristic expression profiles with deregulated genes involved in methylation and acetylation. Moreover, patients with high CyclinA1 expression presented an unfavorable EFS (20.3 versus 51.2% in low CyclinA1 group, P<0.01). Our results suggest that ITD-AR levels and molecular MRD should be considered in planning clinical management of FLT3-ITD patients. Different transcriptional activation of epigenetic and oncogenic profiles may explain variability in outcome among these patients, for whom novel therapeutic approaches are desirable.


Assuntos
Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/genética , Tirosina Quinase 3 Semelhante a fms/genética , Criança , Pré-Escolar , Intervalo Livre de Doença , Epigênese Genética/genética , Regulação Leucêmica da Expressão Gênica , Humanos , Neoplasia Residual/genética , Prognóstico , Estudos Retrospectivos
3.
J Clin Endocrinol Metab ; 97(10): 3414-20, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22851490

RESUMO

CONTEXT: Agenesis of the internal carotid artery and hypoplasia of the internal carotid artery are rare congenital abnormalities, involving less than 0.01% of the general population. Congenital hypopituitarism is also a rare condition; thus, the association of the two entities is unlikely to be casual. We describe one pediatric case of agenesis of the internal carotid artery with hypopituitarism and review other known cases. EVIDENCE ACQUISITION AND SYNTHESIS: In this brief clinical case seminar, we summarize the current understanding of this association based on a MEDLINE search of all peer-reviewed publications (original articles and reviews) on this topic between 1980 and 2011. We found nine other cases, mainly diagnosed during childhood. Defects of pituitary function varied among cases; in four, midline anomalies were present. CONCLUSION: There are two theories that are not mutually exclusive to explain the association of congenital vascular malformation and pituitary hypoplasia with hypopituitarism: the first involves hemodynamic mechanisms, and the second, complex neural-crest differentiation and/or migration disorders. Whatever the real physiopathological mechanism responsible for this condition, it could be considered as a new clinical entity.


Assuntos
Artéria Carótida Interna/anormalidades , Hipopituitarismo/congênito , Hipopituitarismo/patologia , Imageamento por Ressonância Magnética , Feminino , Humanos , Lactente
4.
Int J Immunopathol Pharmacol ; 24(4 Suppl): 7-12, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22032779

RESUMO

The nose plays a primary role within the airways, working as a filter and air-conditioner, together with other important functions. Thus, it is not surprising that nasal diseases are associated with several other comorbidities, including both upper and lower airways, such as bronchial hyperresponsiveness (BHR) and asthma. Several studies have investigated the relationship existing between the upper and the lower airways and new insights are rising. Nevertheless, some uncertainties still remain, mainly because nasal disorders are quite heterogeneous, overlapping (i.e. rhinitis-rhinosinusitis-sinusitis, acute or chronic, allergic or non-allergic) and difficult to diagnose, so that, frequently, many studies don’t differentiate between the various conditions. For this reason, the purpose of this review is to systematically analyze present epidemiological, pathophysiological and clinical data on the relationship between nasal diseases and asthma, splitting up three main conditions: allergic rhinitis, chronic rhinosinusitis and nasal polyposis.


Assuntos
Asma/complicações , Doenças Nasais/complicações , Criança , Humanos , Pólipos Nasais/complicações , Pólipos Nasais/fisiopatologia , Rinite Alérgica Perene/complicações , Rinite Alérgica Perene/fisiopatologia , Rinite Alérgica Sazonal/complicações , Rinite Alérgica Sazonal/fisiopatologia
5.
J Cancer ; 2: 341-6, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21716854

RESUMO

Among the novel biologic therapeutics that will increase our ability to cure human cancer in the years to come, T cell therapy is one of the most promising approaches. However, with the possible exception of tumor-infiltrating lymphocytes therapy for melanoma, clinical trials of adoptive T-cell therapy for solid tumors have so far provided only clear proofs-of-principle to build on with further development. Epstein-Barr virus (EBV)-associated malignancies offer a unique model to develop T cell-based immune therapies, targeting viral antigens expressed on tumor cells. In the last two decades, EBV-specific cytotoxic T-lymphocytes (CTL) have been successfully employed for the prophylaxis and treatment of EBV-related lymphoproliferative disorders in immunocompromised hosts. More recently, this therapeutic approach has been applied to the setting of EBV-related solid tumors, such as nasopharyngeal carcinoma. The results are encouraging, although further improvements to the clinical protocols are clearly necessary to increase anti-tumor activity. Promising implementations are underway, including harnessing the therapeutic potential of CTLs specific for subdominant EBV latent cycle epitopes, and delineating strategies aimed at targeting immune evasion mechanisms exerted by tumor cells.

6.
Bone Marrow Transplant ; 41 Suppl 2: S3-7, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18545240

RESUMO

Over the past decade, relevant improvements and refinements have significantly changed the indications, technique and results obtained with allogeneic hematopoietic SCT (HSCT) in childhood. A fundamental turning point in the history of allogeneic HSCT is represented by the use of placental blood, which was first employed in 1988 in a patient with Fanconi anemia, successfully transplanted with cord blood cells from an HLA-identical sibling. Since then, thousands of children were given an allograft of cord blood-derived hematopoietic progenitors, mainly from an unrelated donor. This large clinical experience has documented that, as compared with BMT, cord blood transplantation (CBT) is associated with reduced incidence and severity of GvHD. The outcome of recipients given unrelated CBT has been reported to be at least as good as that of patients transplanted with either BM or peripheral blood mobilized cells of an unrelated volunteer. Another emerging strategy of HSCT is that of using HLA-partially matched relatives as donors of hematopoietic progenitors. The infusion of a huge number of positively in vitro-selected CD34+ cells, with the concomitant removal of T cells, has been demonstrated to permit sustained engraftment of donor hematopoiesis, without the occurrence of GvHD in the majority of patients transplanted from an HLA-disparate relative. In adults given this type of transplantation, the most favorable results have been reported for AMLs and when the donor displays alloreactivity of natural killer cells. It remains to be definitively proved whether these findings documented in adults maintain their value in pediatric patients transplanted from an HLA-disparate family donor. Finally, the last few years have witnessed the emergence of approaches of adoptive cell therapy aimed at optimizing the results of allograft through strategies able to reinforce immune competence against pathogens, as well as against tumor cells, or at modulating donor T-cell alloreactivity.


Assuntos
Transplante de Células-Tronco de Sangue do Cordão Umbilical , Transplante de Células-Tronco Hematopoéticas , Transplante de Medula Óssea/efeitos adversos , Criança , Sobrevivência de Enxerto , Humanos , Imunoterapia Adotiva , Transplante de Células-Tronco Mesenquimais , Transplante Homólogo
7.
J Microsc ; 218(Pt 2): 180-4, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15857379

RESUMO

We consider the effects of different boundaries on the visibility of a specimen detail providing a compositional contrast in scanning electron microscopy, operating with backscattered electrons or secondary electrons. An object characterized by a gradual variation in composition, an As-doped region in Si, is investigated. The different boundaries in the cross-sectioned specimen correspond to the absence or presence of a poly-Si layer on top of the implanted region, deposited after the annealing treatment. It is shown that the interpretation model used for image formation is of paramount relevance for understanding the experimental results, indicating that the boundaries of the doped region are important in hindering or enhancing its visibility. The relevance of experimental parameters such as electron energy and probe dimension is also reported.

8.
Microsc Microanal ; 11(1): 97-104, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15683576

RESUMO

A conventional scanning electron microscope equipped with a LaB6 source has been modified to operate in a scanning transmission mode. Two detection strategies have been considered, one based on the direct collection of transmitted electrons, the other on the collection of secondary electrons resulting from the conversion of the transmitted ones. Two types of specimens have been mainly investigated: semiconductor multilayers and dopant profiles in As-implanted Si. The results show that the contrast obeys the rules of mass-thickness contrast whereas the resolution is always defined by the probe size independently of specimen thickness and beam broadening. The detection strategy may affect the bright field (light regions look brighter) or dark field (heavy regions look brighter) appearance of the image. Using a direct collection of the transmitted electrons, the contrast can be deduced from the angular distribution of transmitted electrons and their collection angles. When collecting the secondary electrons to explain the image contrast, it is also necessary to take into account the secondary yield dependence on the incidence angle of the transmitted electrons.

9.
Ultramicroscopy ; 99(2-3): 201-9, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15093947

RESUMO

The calibration of a modern electron microscope for Lorentz microscopy observations has been performed using diffractogram, Fresnel diffraction fringe analysis and low-angle electron diffraction methods. An example related to the observations of electrostatic fields associated to a thinned reverse-biased p-n junction is also reported.

10.
Ultramicroscopy ; 94(2): 89-98, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12505758

RESUMO

Experimental and theoretical results on image contrast of semiconductor multi-layers in scanning electron microscopy investigation are reported. Two imaging modes have been considered: backscattered electron imaging of bulk specimen and scanning transmission imaging of thinned specimens. The following main results have been reached. The image resolution of the multi-layers is, in both cases, defined by the probe size. The contrast, governed by density and atomic number differences, is affected by the size of the interaction volume in backscattered electron imaging and by the beam broadening in scanning transmission. Operating in the scanning transmission mode, the contrast of bright field images can be easily related to local variation in atomic number and density of the specimen while the dark field image contrast is strongly affected by electron beam energy, detector collection angles and specimen thickness. All these factors are able to produce contrast reversals that are difficult to explain without the support of a suitable simulation code.

11.
Ultramicroscopy ; 88(2): 139-50, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11419875

RESUMO

Numerical simulations of energy filtering effects on backscattered electron images of semiconductor multilayers are reported. The theoretical investigation has been performed for a wide range of energies, 1-40 keV, and for beam incidence angles between 90 degrees (normal incidence) and 20 degrees. Quite a general purpose of this research concerns the investigation of the optimum energy conditions and of their implications. It will be shown that the optimum energy defines an operating context suitable to ensure a compositional contrast enhancement; i.e. a minimum threshold current and a maximum resolution, without energy filtering, independent of the beam incidence angle. This optimum energy, depending on the specimen and its details, is, however, of the order of a few keV or less for specimen details having a size of the order of few nm. When the performance of the electron gun does not allow to work at low energy it is necessary to operate at an energy higher than the optimum one, the energy filtering can produce positive effects. Yet in those circumstances there is an optimum energy loss window suitable to minimise the threshold current. It spreads from 10-30%, depending on the primary energy and size of the compositional detail, for normal incidence, to a few per cent for high incidence angles and high energy. The simulation results for these last conditions are in agreement with the well-known experimental results obtained with the low-loss methods.

12.
Ultramicroscopy ; 65(1-2): 23-30, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8961547

RESUMO

Comparative studies on the ultimate spatial resolution of the Scanning Electron Microscope, using different components of the electron signal have been performed on specimens providing compositional contrast. By operating the microscope in conventional way as well as with a specifically designed set-up we have ascertained that the delocalized components of the signal provide a spatial resolution of the order of the beam size, even if the practical use can be limited by the noise. To amplify the contribution of the delocalized components of the signal, as backscattered electrons by a bulk specimen or forward scattered electrons by a thin specimen, we used a device consisting of a plate of a material with high secondary yield placed above or below the sample. An important practical implication arises from this study. A detecting system consisting of a standard Everhart-Thornley detector coupled with a converter of backscattered or transmitted electrons represents a high performance detecting device for low voltage observations.


Assuntos
Microscopia Eletrônica de Varredura
14.
Minerva Med ; 82(5): 281-4, 1991 May.
Artigo em Italiano | MEDLINE | ID: mdl-2041618

RESUMO

Despite the fact that it is one of the main and most common neuropsychological complications of cerebral ictus, depression is often overlooked and at times even mistaken for poor motivation, above all in patients with marked speech disorders. Several factors (organic, psychological, social, etc.) contribute to depression and for this reason simple pharmacological treatment is often not sufficient. The paper discusses the most important data taken from the literature relating to this topic.


Assuntos
Transtornos Cerebrovasculares/complicações , Transtorno Depressivo/etiologia , Transtornos Cerebrovasculares/psicologia , Transtorno Depressivo/tratamento farmacológico , Humanos
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