431 research outputs found
Ocorrência de protuberâncias contendo xiloglucano nas paredes celulares da reserva de Hymenaea courbaril L.
Despite the suggestions of its pectic composition, no clear evidence for this has been presented. Here we show the occurrence of such a structure in walls of cells from cotyledons of Hymenaea courbariI L. These cells are known to accumulate large amounts of storage xyloglucan in the wall and, in this case, the protuberances seem to contain this storage polysaccharide rather than pectin. A hypothetical sequence of events leading from wall strands to protuberances was assembled based on scanning electron microscopy observations. On this basis, a tentative model for how polysaccharides are distributed into the wall, near the regions where protuberances are found, is proposed to explain the presence of storage xyloglucan in their composition.Apesar das sugestões da sua composição péctica, não foram apresentadas evidências diretas da sua composição. Neste trabalho é mostrada a ocorrência desta estrutura em paredes de células parenquimáticas de cotilédones de Hymenaea courbaril L. Sabe-se que estas células acumulam grandes quantidades de xiloglucano nas suas paredes e, nesse caso, as protuberâncias parecem conter este polissacarÃdeo na sua constituição. Uma seqüência de eventos que leva ao aparecimento destas protuberâncias é sugerida e um modelo de parede celular é proposto para explicar a presença de xiloglucano de reserva na composição das protuberâncias.415419Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento CientÃfico e Tecnológico (CNPq
Biochemical and morphological responses to abiotc elicitor chitin in suspension-cultured sugarcane cells.
Noise reduction in muon tomography for detecting high density objects
The muon tomography technique, based on multiple Coulomb scattering of cosmic
ray muons, has been proposed as a tool to detect the presence of high density
objects inside closed volumes. In this paper a new and innovative method is
presented to handle the density fluctuations (noise) of reconstructed images, a
well known problem of this technique. The effectiveness of our method is
evaluated using experimental data obtained with a muon tomography prototype
located at the Legnaro National Laboratories (LNL) of the Istituto Nazionale di
Fisica Nucleare (INFN). The results reported in this paper, obtained with real
cosmic ray data, show that with appropriate image filtering and muon momentum
classification, the muon tomography technique can detect high density
materials, such as lead, albeit surrounded by light or medium density material,
in short times. A comparison with algorithms published in literature is also
presented
A diachronic-comparative analysis for the identification of the most powerful prognostic index for localized diffuse large B-cell lymphoma
BACKGROUND:
In the rituximab era, the conventional International Prognostic index (IPI) lost at least in part its predictive power, while the National Comprehensive Cancer Network-IPI (NCCN-IPI) seems to be a new and valid prognosticator. However, it has not yet been evaluated in patients with localized disease and it has not been compared with the modified IPI (mIPI) of the pre-rituximab era. In order to evaluate the different prognosticators and to assess the importance of rituximab and radiotherapy (RT), we carried out the so far largest retrospective analysis of patients with localized diffuse large B-cell lymphoma (DLBCL).
PATIENTS AND METHODS:
We retrospectively assessed clinical and therapeutical data of 1405 patients treated in from 1987 to 2012 in 10 cancer centers in Italy and 1 in Austria.
RESULTS:
All patients underwent an anthracycline containing polychemotherapy and 254 additional rituximab. The median follow-up was 5.7 years (range 0.1-23 years). The 5-year overall survival (OS) was 75%, being significantly superior in those who underwent additional rituximab, while RT consolidation did not improve the outcome of those who received immunochemotherapy. Patients with extranodal disease benefited from the addition of rituximab, while RT did not improve OS of the immunochemotherapy subgroup. In the pre-rituximab era, the mIPI showed a better performance than the others. In rituximab-treated patients, the NCCN-IPI had the highest discriminant value and the 5-years OS varied significantly (P < 0.001) between the three risk groups and was 98% in low-risk patients, 82% in those with a low-intermediate risk and 57% among high-intermediate and high-risk cases.
CONCLUSIONS:
The NCCN-IPI is so far the best prognosticator for patients with localized DLBCL who underwent R-CHOP(-like). The addition of rituximab is indispensable regardless of the risk category and site of involvement, while the addition of RT should be reserved to those cases who are ineligible to rituximab
statistics biomedicine and scientific fraud
A consistent fraction of published data on scientific journals is not reproducible mainly due to insufficient knowledge of statistical methods. Here, we discuss on the use of proper statistical tools in biomedical research and statistical pitfalls potentially undermining the scientific validity of published data. Apart from unaware errors, a growing concern exists regarding data fabrication and scientific misconduct. Indeed, the social impact of false scientific data can be largely unpredictable and devastating, as shown by the worldwide dramatic effects on vaccinations coverage following a retracted paper published on a highly authoritative medical journal. Unfortunately, statistics shows a quite limited power in detecting false science, although a few statistical tools, such as the Benford's law, are known. Taken together, statistics in biomedical sciences i) is a powerful tool to interpret experimental data; ii) has limited power in detecting false science; and iii) first and foremost, is not the result of a simple "click of a mouse", but should be the result of accurate research planning by experienced and knowledgeable users
Clofarabine and Treosulfan as Conditioning for Matched Related and Unrelated Hematopoietic Stem Cell Transplantation: Results from the Clo3o Phase II Trial
A multicenter retrospective clinical study of CD5/CD10-negative chronic B cell leukemias.
CD5-negative chronic B cell lymphoproliferative disorders in leukemic phase (B-CLPD) are heterogeneous and relatively uncommon pathologies that often lack a histopathological definition because of the absence of accessible pathological tissue. We describe the clinical features and evolution-related variables of 156 patients with CD5/CD10-negative B-CLPD (median age 66 years, range 25-86). The median follow-up was 51 months (range 6-216), and overall 3- and 5-year survival was respectively 87 and 76%; 50 patients needed therapy at diagnosis, 56 during follow-up, and 50 remained untreated until the last control. A combined clinical, histological, cytomorphological, immunophenotypical, and cytogenetic diagnostic approach allowed the complete classification of only a minority of patients as being affected by splenic marginal zone or lymphoplasmacytic lymphoma; the majority of cases remained unclassifiable. Multivariate analysis showed that the clinicohematological variables adversely related to overall survival were serum LDH levels and age, whereas high serum LDH levels, hemoglobin levels of <11 g/dl, and splenomegaly related to treatment-free time (in "wait and see" cases); only splenomegaly related to time to progression (in treated patients). In conclusion, our retrospective study describes the clinical features and variables related to evolution in a large group of patients with CD5/CD10-negative chronic B-cell lymphoid leukemias and underlines the fact that a probable lymphoplasmacytic or marginal zone normal cell origin can be supposed in such leukemic forms, but never surely demonstrated
Persistent Unresolved Inflammation in the Mecp2-308 Female Mutated Mouse Model of Rett Syndrome
Rett syndrome (RTT) is a rare neurodevelopmental disorder usually caused by mutations in the X-linked gene methyl-CpG-binding protein 2 (MECP2). Several Mecp2 mutant mouse lines have been developed recapitulating part of the clinical features. In particular, Mecp2-308 female heterozygous mice, bearing a truncating mutation, are a validated model of the disease. While recent data suggest a role for inflammation in RTT, little information on the inflammatory status in murine models of the disease is available. Here, we investigated the inflammatory status by proteomic 2-DE/MALDI-ToF/ToF analyses in symptomatic Mecp2-308 female mice. Ten differentially expressed proteins were evidenced in the Mecp2-308 mutated plasma proteome. In particular, 5 positive acute-phase response (APR) proteins increased (i.e., kininogen-1, alpha-fetoprotein, mannose-binding protein C, alpha-1-antitrypsin, and alpha-2-macroglobulin), and 3 negative APR reactants were decreased (i.e., serotransferrin, albumin, and apolipoprotein A1). CD5 antigen-like and vitamin D-binding protein, two proteins strictly related to inflammation, were also changed. These results indicate for the first time a persistent unresolved inflammation of unknown origin in the Mecp2-308 mouse model
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