1,348 research outputs found
Primary Hepatosplenic Large B-Cell Lymphoma: A Rare Aggressive Tumor
Diffuse large B-cell lymphoma is the most common form of lymphoma. It usually begins in the lymph nodes; up to 40% may have an extranodal presentation. According to a definition of primary extranodal lymphoma with presentation only in extranodal sites, there are reports of large B-cell lymphomas limited to liver or spleen as separate entities, and to date there have been only three documented cases of primary hepatosplenic presentation. This paper reports a fourth case. Due to a review of the literature and the clinical course of the case reported, we conclude that primary hepatosplenic large B-cell lymphoma has been found predominantly in females older than 60 years. The patients reported had <2 months of evolution prior to diagnosis, prominent B symptoms, splenomegaly in three and hepatomegaly in two, none with lymph node involvement. All had thrombocytopenia and abnormal liver function tests; three had anemia and elevated serum lactic dehydrogenase levels, two with hemophagocytosis in bone marrow. Because of the previously mentioned data, it can be stated that primary hepatosplenic lymphoma is an uncommon and aggressive form of disease that requires immediate recognition and treatment
One for All—A Highly Efficient and Versatile Method for Fluorescent Immunostaining in Fish Embryos
Background: For the detection and sub-cellular (co)-localization of proteins in the context of the tissue or organism immunostaining in whole mount preparations or on sections is still the best approach. So far, each antibody required its own fixation and antigen retrieval protocol so that optimizing immunostaining turned out to be tedious and time consuming. Methodology/Principal Finding: Here we present a novel method to efficiently retrieve the antigen in a widely applicable standard protocol, facilitating fluorescent immunostaining of both cryosections and whole mount preparations in zebrafish (Danio rerio) and medaka (Oryzias latipes). Conclusions/Significance: Our method overcomes the loss of sections and damage of tissue and cell morphology, and allows parallel immunostaining in multiple colors, co-immunostaining with fluorescent proteins in transgenic fish lines and in combination with whole mount in situ hybridization
Regulation of articular chondrocyte catabolic genes by growth factor interaction
Osteoarthritis is characterized by a loss of articular cartilage homeostasis in which degradation exceeds formation. Several growth factors have been shown to promote cartilage formation by augmenting articular chondrocyte anabolic activity. This study tests the hypothesis that such growth factors also play an anti-catabolic role. We transferred individual or combinations of the genes encoding insulin- like growth factor I, bone morphogenetic protein-2, bone morphogenetic protein-7, transforming growth factor-β1 and fibroblast growth factor-2, into adult bovine articular chondrocytes and measured the expression of catabolic marker genes encoding A disintegrin and metalloproteinase with thrombospondin motifs-4 and −5, matrix metalloproteinases-3 and −13, and interleukin-6. When delivered individually, or in combination, these growth factor transgenes differentially regulated the direction, magnitude and time course of expression of the catabolic marker genes. In concert, the growth factor transgenes regulated the marker genes in an interactive fashion that ranged from synergistic inhibition to synergistic stimulation. Synergistic stimulation prevailed over synergistic inhibition, reaching maxima of 15.2-fold and 2.7-fold, respectively. Neither the magnitude nor the time course of the effect of the transgene combinations could be predicted on the basis of the individual transgene effects. With few exceptions, the data contradict our hypothesis. The results demonstrate that growth factors that are traditionally viewed as chondrogenic tend also to promote catabolic gene expression. The competing actions of these potential therapeutic agents add an additional level of complexity to the selection of regulatory factors for restoring articular cartilage homeostasis or promoting repair
The plant pathogen Pseudomonas syringae pv. tomato is genetically monomorphic and under strong selection to evade tomato immunity
addresses: Department of Plant Pathology, Physiology, and Weed Science, Virginia Tech, Blacksburg, Virginia, United States of America.notes: PMCID: PMC3161960types: Journal Article; Research Support, U.S. Gov't, Non-P.H.S.This is an open-access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.Recently, genome sequencing of many isolates of genetically monomorphic bacterial human pathogens has given new insights into pathogen microevolution and phylogeography. Here, we report a genome-based micro-evolutionary study of a bacterial plant pathogen, Pseudomonas syringae pv. tomato. Only 267 mutations were identified between five sequenced isolates in 3,543,009 nt of analyzed genome sequence, which suggests a recent evolutionary origin of this pathogen. Further analysis with genome-derived markers of 89 world-wide isolates showed that several genotypes exist in North America and in Europe indicating frequent pathogen movement between these world regions. Genome-derived markers and molecular analyses of key pathogen loci important for virulence and motility both suggest ongoing adaptation to the tomato host. A mutational hotspot was found in the type III-secreted effector gene hopM1. These mutations abolish the cell death triggering activity of the full-length protein indicating strong selection for loss of function of this effector, which was previously considered a virulence factor. Two non-synonymous mutations in the flagellin-encoding gene fliC allowed identifying a new microbe associated molecular pattern (MAMP) in a region distinct from the known MAMP flg22. Interestingly, the ancestral allele of this MAMP induces a stronger tomato immune response than the derived alleles. The ancestral allele has largely disappeared from today's Pto populations suggesting that flagellin-triggered immunity limits pathogen fitness even in highly virulent pathogens. An additional non-synonymous mutation was identified in flg22 in South American isolates. Therefore, MAMPs are more variable than expected differing even between otherwise almost identical isolates of the same pathogen strain
Comparison of methods for the detection of biofilm production in coagulase-negative staphylococci
<p>Abstract</p> <p>Background</p> <p>The ability of biofilm formation seems to play an essential role in the virulence of coagulase-negative staphylococci (CNS). The most clearly characterized component of staphylococcal biofilms is the polysaccharide intercellular adhesin (PIA) encoded by the <it>icaADBC </it>operon. Biofilm production was studied in 80 coagulase-negative staphylococci (CNS) strains isolated from clinical specimens of newborns with infection hospitalized at the Neonatal Unit of the University Hospital, Faculty of Medicine of Botucatu, and in 20 isolates obtained from the nares of healthy individuals without signs of infection. The objective was to compare three phenotypic methods with the detection of the <it>icaA</it>, <it>icaD </it>and <it>icaC </it>genes by PCR.</p> <p>Findings</p> <p>Among the 100 CNS isolates studied, 82% tested positive by PCR, 82% by the tube test, 81% by the TCP assay, and 73% by the CRA method. Using PCR as a reference, the tube test showed the best correlation with detection of the <it>ica </it>genes, presenting high sensitivity and specificity.</p> <p>Conclusions</p> <p>The tube adherence test can be indicated for the routine detection of biofilm production in CNS because of its easy application and low cost and because it guarantees reliable results with excellent sensitivity and specificity.</p
Dusty Planetary Systems
Extensive photometric stellar surveys show that many main sequence stars show
emission at infrared and longer wavelengths that is in excess of the stellar
photosphere; this emission is thought to arise from circumstellar dust. The
presence of dust disks is confirmed by spatially resolved imaging at infrared
to millimeter wavelengths (tracing the dust thermal emission), and at optical
to near infrared wavelengths (tracing the dust scattered light). Because the
expected lifetime of these dust particles is much shorter than the age of the
stars (>10 Myr), it is inferred that this solid material not primordial, i.e.
the remaining from the placental cloud of gas and dust where the star was born,
but instead is replenished by dust-producing planetesimals. These planetesimals
are analogous to the asteroids, comets and Kuiper Belt objects (KBOs) in our
Solar system that produce the interplanetary dust that gives rise to the
zodiacal light (tracing the inner component of the Solar system debris disk).
The presence of these "debris disks" around stars with a wide range of masses,
luminosities, and metallicities, with and without binary companions, is
evidence that planetesimal formation is a robust process that can take place
under a wide range of conditions. This chapter is divided in two parts. Part I
discusses how the study of the Solar system debris disk and the study of debris
disks around other stars can help us learn about the formation, evolution and
diversity of planetary systems by shedding light on the frequency and timing of
planetesimal formation, the location and physical properties of the
planetesimals, the presence of long-period planets, and the dynamical and
collisional evolution of the system. Part II reviews the physical processes
that affect dust particles in the gas-free environment of a debris disk and
their effect on the dust particle size and spatial distribution.Comment: 68 pages, 25 figures. To be published in "Solar and Planetary
Systems" (P. Kalas and L. French, Eds.), Volume 3 of the series "Planets,
Stars and Stellar Systems" (T.D. Oswalt, Editor-in-chief), Springer 201
Determinantes psicológicos de la adherencia al tratamiento del VIH en una universidad pública del Estado de México
La adherencia al tratamiento al ser una fase sustancial del sistema de salud pública refleja una problemática institucional en cuanto a valores y normas no siempre compatibles entre profesionistas y familiares de portadores de VIH / SIDA cuyo propósito es reducir los efectos de la enfermedad en la calidad de vida y el bienestar subjetivo. Precisamente, el objetivo del presente estudio fue modelar los factores determinantes de la adherencia al tratamiento con la finalidad de discutir y complementar los hallazgos de la literatura revisada.Se llevó a cabo un estudio no experimental, trasversal y correlacional con una selección no probabilística de 194 estudiantes de una universidad pública del Estado de México. A partir de un modelo de regresión lineal múltiple ⌠β = 0,702; R = 0,645; R2 = 0,080; R2 ajustada = 0,070; p < 0,001⌡ se encontró que la percepción del tipo de relación de pareja determinó la adherencia al tratamiento. Con base en los resultados de los estudios citados se advierten líneas de investigación relativas al efecto de la disponibilidad de tratamientos y medicamentos sobre la adherencia al tratamiento
Indivo: a personally controlled health record for health information exchange and communication
<p>Abstract</p> <p>Background</p> <p>Personally controlled health records (PCHRs), a subset of personal health records (PHRs), enable a patient to assemble, maintain and manage a secure copy of his or her medical data. Indivo (formerly PING) is an open source, open standards PCHR with an open application programming interface (API).</p> <p>Results</p> <p>We describe how the PCHR platform can provide standard building blocks for networked PHR applications. Indivo allows the ready integration of diverse sources of medical data under a patient's control through the use of standards-based communication protocols and APIs for connecting PCHRs to existing and future health information systems.</p> <p>Conclusion</p> <p>The strict and transparent personal control model is designed to encourage widespread participation by patients, healthcare providers and institutions, thus creating the ecosystem for development of innovative, consumer-focused healthcare applications.</p
The ADAMTS (A Disintegrin and Metalloproteinase with Thrombospondin motifs) family
The ADAMTS (A Disintegrin and Metalloproteinase with Thrombospondin motifs) enzymes are secreted, multi-domain matrix-associated zinc metalloendopeptidases that have diverse roles in tissue morphogenesis and patho-physiological remodeling, in inflammation and in vascular biology. The human family includes 19 members that can be sub-grouped on the basis of their known substrates, namely the aggrecanases or proteoglycanases (ADAMTS1, 4, 5, 8, 9, 15 and 20), the procollagen N-propeptidases (ADAMTS2, 3 and 14), the cartilage oligomeric matrix protein-cleaving enzymes (ADAMTS7 and 12), the von-Willebrand Factor proteinase (ADAMTS13) and a group of orphan enzymes (ADAMTS6, 10, 16, 17, 18 and 19). Control of the structure and function of the extracellular matrix (ECM) is a central theme of the biology of the ADAMTS, as exemplified by the actions of the procollagen-N-propeptidases in collagen fibril assembly and of the aggrecanases in the cleavage or modification of ECM proteoglycans. Defects in certain family members give rise to inherited genetic disorders, while the aberrant expression or function of others is associated with arthritis, cancer and cardiovascular disease. In particular, ADAMTS4 and 5 have emerged as therapeutic targets in arthritis. Multiple ADAMTSs from different sub-groupings exert either positive or negative effects on tumorigenesis and metastasis, with both metalloproteinase-dependent and -independent actions known to occur. The basic ADAMTS structure comprises a metalloproteinase catalytic domain and a carboxy-terminal ancillary domain, the latter determining substrate specificity and the localization of the protease and its interaction partners; ancillary domains probably also have independent biological functions. Focusing primarily on the aggrecanases and proteoglycanases, this review provides a perspective on the evolution of the ADAMTS family, their links with developmental and disease mechanisms, and key questions for the future
PhosTryp: a phosphorylation site predictor specific for parasitic protozoa of the family trypanosomatidae
<p>Abstract</p> <p>Background</p> <p>Protein phosphorylation modulates protein function in organisms at all levels of complexity. Parasites of the <it>Leishmania </it>genus undergo various developmental transitions in their life cycle triggered by changes in the environment. The molecular mechanisms that these organisms use to process and integrate these external cues are largely unknown. However <it>Leishmania </it>lacks transcription factors, therefore most regulatory processes may occur at a post-translational level and phosphorylation has recently been demonstrated to be an important player in this process. Experimental identification of phosphorylation sites is a time-consuming task. Moreover some sites could be missed due to the highly dynamic nature of this process or to difficulties in phospho-peptide enrichment.</p> <p>Results</p> <p>Here we present PhosTryp, a phosphorylation site predictor specific for trypansomatids. This method uses an SVM-based approach and has been trained with recent <it>Leishmania </it>phosphosproteomics data. PhosTryp achieved a 17% improvement in prediction performance compared with Netphos, a non organism-specific predictor. The analysis of the peptides correctly predicted by our method but missed by Netphos demonstrates that PhosTryp captures <it>Leishmania</it>-specific phosphorylation features. More specifically our results show that <it>Leishmania </it>kinases have sequence specificities which are different from their counterparts in higher eukaryotes. Consequently we were able to propose two possible <it>Leishmania</it>-specific phosphorylation motifs.</p> <p>We further demonstrate that this improvement in performance extends to the related trypanosomatids <it>Trypanosoma brucei </it>and <it>Trypanosoma cruzi</it>. Finally, in order to maximize the usefulness of PhosTryp, we trained a predictor combining all the peptides from <it>L. infantum, T. brucei and T. cruzi</it>.</p> <p>Conclusions</p> <p>Our work demonstrates that training on organism-specific data results in an improvement that extends to related species. PhosTryp is freely available at <url>http://phostryp.bio.uniroma2.it</url></p
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