108 research outputs found

    Mutations in Exons 8 and 11 of c-kit Gene in Canine Subcutaneous Mast Cell Tumors and Their Association with Cell Proliferation

    Get PDF
    The prognostic significance of internal tandem duplication (ITD) mutations in exons 8 and 11 of c-kit has been well-described for canine cutaneous mast cell tumors (MCTs), but c-kit mutations have rarely been reported in subcutaneous MCTs. The objective of this study was to identify the prevalence of ITD mutations in exons 8 and 11 of c-kit in canine subcutaneous MCTs and to investigate its association with histologic grade, KIT pattern, and proliferation markers. ITD mutations in exons 8 and 11 of c-kit, mitotic count, Ki67 index, AgNOR number, Ki67xAgNOR score, KIT pattern, and histologic grade (two-tier system) were retrospectively recorded for 216 dogs with subcutaneous MCTs. ITD mutations in exons 8 and 11 of c-kit were detected in 23 (10.6%) and 12 (5.56%) subcutaneous MCTs, respectively. Exon 11 mutations were significantly associated with Kiupel high grade (p < 0.001) and increased mitotic count (p < 0.001) compared to subcutaneous MCTs with no mutations in exons 8 or 11 (p = 0.002) or subcutaneous MCTs with a mutation in exon 8 (p = 0.001). There was no significant association of either c-kit mutation with KIT patterns or proliferation activity. This study identified a higher prevalence of ITD mutations in exons 8 and 11 of c-kit in subcutaneous MCTs than previously reported. Like their cutaneous counterpart, subcutaneous MCTs with exon 11 mutations were more likely to be histologically high grade and have a higher mitotic count, whereas such associations were not observed in subcutaneous MCTs with exon 8 mutations

    Evaluation of CD45 protein expression and transcript in canine small clear cell/T zone lymphoma.

    Get PDF
    Canine small clear cell lymphoma is a peculiar lymphoma entity with T-zone histopathological pattern andindolent clinical course. From an immunophenotypic point of view the main feature is the lack of CD45 staining by flow-cytometry (FC), which accounts for >95% of cases. Underlying mechanisms have never been investigated.Aim of this work was to evaluate CD45 protein and mRNA expression in small clear cell lymphoma.Lymph nodes of 18 cases and 11 controls, with either reactive hyperplasia or CD45-positive high grade T-cell lymphoma, were investigated. FC was performed on lymph node fine needle aspiration and CD45 median fluorescence intensity (MFI) was then evaluated on small clear cells and normal residual T-lymphocytes. CD45 surface expression was also evaluated by immunohistochemical reaction on paraffin wax-embedded lymph node sections.Quantitative real-time RT-PCR was performed on cases and controls. Total RNA was isolated from cell suspension in RNA later. The generated CD45cDNA was amplified and ΔΔCt method was used for the relative mRNA quantification.CD45-MFI in neoplastic cells was <1% compared to normal residual T-lymphocytes in the same sample. Cells were also negative for CD45 stain on histopathological preparations. RT-PCR showed a significantly lower amount of CD45 transcript in neoplastic samples compared to controls, likely due to the residual population.Results showed the lack of CD45 surface antigen and the virtually absence of CD45-mRNA in small clear cell lymphoma. We hypothesize a possible genomic/epigenomic aberration; further studies are in progress to investigate the pathogenesis of this aberrancy and the possible linkage to lymphomagenesis

    POT1 mutations are frequent and associated with Ki-67 index in canine diffuse large B-cell lymphoma

    Get PDF
    Diffuse large B-cell lymphoma (DLBCL) represents one of the most frequent and deadliest neoplasia in dogs worldwide and is characterized by a remarkable degree of clinical heterogeneity, with poor chances to anticipate the outcome. Even if in the last years some recurrently mutated genes have been identified, the genetic origin of canine DLBCL (cDLBCL) is not yet completely understood. The aim of the present study was to assess the prevalence of POT1 mutations in cDLBCL and to elucidate the role of such gene in the pathogenesis of this tumor. Mutations in POT1 were retrieved in 34% of cases, in line with previous reports, but no significant associations with any clinico-pathological variable were identified. Likewise, POT1 mutations are not predictive of worse prognosis. Interestingly, Ki-67 index was significantly higher in dogs harboring POT1 mutations compared to wild-type ones. These results suggest that POT1 mutations may exert their pathogenic role in cDLBCL by promoting cellular proliferation

    Phenotypical Characterization and Clinical Outcome of Canine Burkitt-Like Lymphoma

    Get PDF
    In dogs, Burkitt-like lymphoma (B-LL) is rare tumor and it is classified as a high-grade B-cell malignancy. The diagnosis is challenging because of the similar histologic appearance with other histotypes, no defined phenotypical criteria and poorly described clinical aspects. The aim of the study was to provide a detailed description of clinical and morphological features, as well as immunophenotypical profile of B-LL in comparison with the human counterpart. Thirteen dogs with histologically proven B-LL, for which a complete staging and follow-up were available, were retrospectively selected. Immunohistochemical expression of CD20, PAX5, CD3, CD10, BCL2, BCL6, MYC, and caspase-3 was evaluated. Histologically, all B-LLs showed a diffuse architecture with medium to large-sized cells, high mitotic rate and diffuse starry sky appearance. B-phenotype of neoplastic cells was confirmed both by flow-cytometry and immunohistochemistry. Conversely, B-LLs were negative for BCL2 and MYC, whereas some cases co-expressed BCL6 and CD10, suggesting a germinal center B-cell origin. Disease stage was advanced in the majority of cases. All dogs received CHOP-based chemotherapy with or without immunotherapy. Despite treatment, prognosis was poor, with a median time to progression and survival of 130 and 228 days, respectively. Nevertheless, ~30% of dogs survived more than 1 year. An increased apoptotic index, a high turnover index and caspase-3 index correlated with shorter survival. In conclusion, canine B-LL shows phenotypical differences with the human counterpart along with features that might help to differentiate this entity from diffuse large B-cell lymphoma

    A Retrospective Clinico-Pathologic Study of 35 Dogs with Urethral Transitional Cell Carcinoma Undergoing Treatment

    Get PDF
    : Chemotherapy and cyclooxygenase inhibitors (COXi) are primary treatments for canine urethral transitional cell carcinoma (uTCC), a tumor known for its aggressiveness and poor prognosis. This retrospective study aimed to evaluate the clinico-pathological characteristics, treatment modalities, and prognostic factors of 35 dogs with confirmed uTCC that received chemotherapy and COXi. Upon admission, urethral obstruction (UO) and urinary tract infection (UTI) were observed in seven (20%) dogs each. Gemcitabine (n = 20; 57.1%) and vinblastine (n = 10; 28.6%) were commonly used as first-line therapies, with four dogs also receiving radiation therapy. Based on RECIST, one (2.9%) dog achieved complete remission, nine (25.7%) partial remission, 20 (57.14%) showed stable disease, and five (14.3%) progressed. Among dogs with UO, six (85.7%) showed resolution or improvement after the first chemotherapy dose. The median time to local progression was 171 days (range: 107-235), and the median survival time was 333 days (range: 158-508). Dogs with UO upon admission had a higher risk of local progression, while both UO and UTI were associated with an increased risk of overall disease progression and tumor-related death. Additionally, gemcitabine significantly improved metastatic control. This study identified UO and UTI as negative prognostic factors, highlighting the importance of a multimodal approach in managing uTCC

    Long Non-Coding RNAs as Molecular Signatures for Canine B-Cell Lymphoma Characterization

    Get PDF
    Background: Diffuse large B-cell lymphoma (DLBCL), marginal zone lymphoma (MZL) and follicular lymphoma (FL) are the most common B-cell lymphomas (BCL) in dogs. Recent investigations have demonstrated overlaps of these histotypes with the human counterparts, including clinical presentation, biologic behavior, tumor genetics, and treatment response. The molecular mechanisms that underlie canine BCL are still unknown and new studies to improve diagnosis, therapy, and the utilization of canine species as spontaneous animal tumor models are undeniably needed. Recent work using human DLBCL transcriptomes has suggested that long non-coding RNAs (lncRNAs) play a key role in lymphoma pathogenesis and pinpointed a restricted number of lncRNAs as potential targets for further studies. Results: To expand the knowledge of non-coding molecules involved in canine BCL, we used transcriptomes obtained from a cohort of 62 dogs with newly-diagnosed multicentric DLBCL, MZL and FL that had undergone complete staging work-up and were treated with chemotherapy or chemo-immunotherapy. We developed a customized R pipeline performing a transcriptome assembly by multiple algorithms to uncover novel lncRNAs, and delineate genome-wide expression of unannotated and annotated lncRNAs. Our pipeline also included a new package for high performance system biology analysis, which detects high-scoring network biological neighborhoods to identify functional modules. Moreover, our customized pipeline quantified the expression of novel and annotated lncRNAs, allowing us to subtype DLBCLs into two main groups. The DLBCL subtypes showed statistically different survivals, indicating the potential use of lncRNAs as prognostic biomarkers in future studies. Conclusions: In this manuscript, we describe the methodology used to identify lncRNAs that differentiate B-cell lymphoma subtypes and we interpreted the biological and clinical values of the results. We inferred the potential functions of lncRNAs to obtain a comprehensive and integrative insight that highlights their impact in this neoplasm

    Vortex-induced nonlinearity and the effects of ion irradiation on the high-frequency response of NbTi films

    Get PDF
    The microwave response of superconducting devices can be affected by nonlinearity effects of both intrinsic and extrinsic origin. In this study, we report on the nonlinear behavior of NbTi microwave resonators, in the presence of dc magnetic fields up to 4 T. The aim of this work is to characterize the vortex-induced nonlinearity, which in these conditions of frequency (11 GHz) and fields is expected to give the major contribution to dissipation, when the circulating rf current exceeds a given threshold. Nonlinearity is investigated by analyzing -degradation and resonance curve distortion as a function of the input rf power, while the emergence of sharp discontinuities is associated to the existence of an rf limiting current density. The current densities corresponding to the onset of these features are compared to the critical current density from dc measurements, helping us to outline a comprehensive picture. Moreover, the pinning constant was extracted as a function of temperature by means of a Gittleman–Rosenblum analysis, revealing the prominent role of type pinning. We also analyzed the effects of introducing controlled artificial disorder and pinning sites through 1.5-MeV proton irradiation. After irradiation, we observed an increase of both the pinning constant and the in-field nonlinearity threshold and limiting current

    Education in the stricto sensu: Perspectives and Development of Continuing Interdisciplinary Practice

    Get PDF
    El Programa de Maestría Académica en Enseñanza PPGEn fue creado vía Término de Cooperación Técnica Científica entre el Instituto Federal de Educación, Ciencia y Tecnología de Mato Grosso-IFMT y Universidad de Cuiabá-UNIC, mediante Resolución CONSUP IFMT nº 100 el 26 de noviembre de. El curso tiene por objetivo el desarrollo de un trabajo interdisciplinario que integre las diversas áreas del conocimiento. Este artículo resulta de la práctica de la investigadora como docente del Programa y tiene por objetivo comprender sobre la enseñanza de la formación ofrecida por el programa a sus discentes en la perspectiva interdisciplinaria. Se trata de una investigación cualitativa, que utilizó como metodología las Narrativas de Formación, que trabaja puntualmente con recorridos personales y colectivos de sujetos involucrados en ambientes educativos. Como resultado, se percibió que la práctica desarrollada en el Máster en Enseño ocurre mediante la percepción de que el profesor es por excelencia investigador, posibilidad que la práctica interdisciplinaria desarrollada mediante acciones colectivas ha generado. Esta ha sido realizada como reflexión de la acción pedagógica educativa, para posibilitar que el docente la examine con la mirada de quien es mediador del proceso de construcción de saberes.O Programa de Mestrado Acadêmico em Ensino PPGEn foi criado via Termo de Cooperação Técnico Científico (Autores, verifiquem se é cientifico ou cientifica???) entre Instituto Federal de Educação, Ciência e Tecnologia de Mato Grosso- IFMT e Universidade de Cuiabá- UNIC, mediante Resolução CONSUP IFMT nº 100 em 26 de novembro de 2015.O curso tem por intento o desenvolvimento de um trabalho interdisciplinar que integre as diversas áreas do conhecimento. Este artigo resulta da prática da pesquisadora como docente do Programa e tem por objetivo compreender sobre o ensino da formação oferecida pelo programa aos seus discentes na perspectiva interdisciplinar. Os autores que sustentam o estudo discutem sobre formação de professores que envolvem saberes docentes, professor reflexivo e interdisciplinaridade. Trata-se de uma pesquisa qualitativa, que utilizou como metodologia as Narrativas de Formação, que trabalha pontualmente com percursos pessoais e coletivos de sujeitos envolvidos em ambientes educativos. Como resultado, percebeu-se que a prática desenvolvida no Mestrado em Ensino ocorre mediante a percepção de que o professor é por excelência pesquisador, possibilidade que a prática interdisciplinar desenvolvida mediante ações coletivas tem gerado. Esta tem sido realizada como reflexão da ação pedagógica educativa, para possibilitar que o docente a examine com o olhar de quem é mediador do processo de construção de saberes.The Academic Master's Program in Teaching PPGEn was created by means of a Technical Scientific Cooperation Agreement between the Federal Institute of Education, Science and Technology of Mato Grosso - IFMT and University of Cuiabá-UNIC, through Resolution CONSUP IFMT nº 100 on November 26 The course aims to develop an interdisciplinary work that integrates the different areas of knowledge. This article results from the practice of the researcher as a teacher of the Program and aims to understand about the teaching of the training offered by the program to its students in the interdisciplinary perspective. It is a qualitative research that used as a methodology the Training Narratives, which works punctually with personal and collective paths of subjects involved in educational environments. As a result, it was realized that the practice developed in the Master in Teaching takes place through the perception that the teacher is par excellence researcher, possibility that the interdisciplinary practice developed through collective actions has generated. This has been done as a reflection of educational pedagogical action, to enable the teacher to examine it with the look of who is mediator of the process of knowledge construction
    corecore