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1.
Vet Comp Oncol ; 16(2): 253-261, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29235249

RESUMO

Hemangiosarcoma (HSA) is a highly malignant tumour with aggressive biological behaviour. HSAs are more common in dogs than other domestic animals. The median survival time of dogs with HSA remains short, even with chemotherapy and surgery. Therefore, there is a critical need to improve the adjuvant chemotherapeutic regimens to improve clinical outcomes in dogs with HSA. Resveratrol has been shown to possess strong anti-proliferative and/or pro-apoptotic properties in human cancer cell lines. Nevertheless, the potential anticancer effects of resveratrol have not been reported in canine HSAs. The objective of this study is to determine the growth inhibitory effects of resveratrol in HSA cells when used alone or in combination with doxorubicin, a commonly used chemotherapeutic agent. Frog and DD-1 canine HSA cell lines were treated with varying concentrations of resveratrol with and without doxorubicin. Cell viability was measured by the MTT assay. The expression of apoptotic proteins, activation of p38 mitogen-activated protein kinase (MAPK), AMP-activated protein kinase (AMPK) and extracellular signal-regulated kinase 1/2 (ERK1/2) were assessed by western blotting. Similar to human cancer cell lines, resveratrol markedly inhibited the growth and induced apoptosis in both HSA cell lines. Mechanistically, resveratrol activated p38 MAPK, but did not affect the AMPK or the ERK1/2 pathways. Additional experiments showed that resveratrol augmented the growth-inhibitory and apoptotic effects of doxorubicin in both HSA cell lines. These findings suggest that resveratrol has pro-apoptotic effects in canine HSA cells; therefore, its use as a potential adjunct therapy in canine HSA patients warrants further investigation.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Doenças do Cão/tratamento farmacológico , Hemangiossarcoma/veterinária , Estilbenos/farmacologia , Análise de Variância , Animais , Antibióticos Antineoplásicos , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Anuros , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral/efeitos dos fármacos , Doenças do Cão/patologia , Cães , Doxorrubicina/farmacologia , Hemangiossarcoma/tratamento farmacológico , Hemangiossarcoma/patologia , Resveratrol
2.
Vet Comp Oncol ; 15(3): 868-880, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27001524

RESUMO

One of the primary objectives of the Oncology Pathology Working Group (OPWG), a joint initiative of the Veterinary Cancer Society and the American College of Veterinary Pathologists, is for oncologists and pathologists to collaboratively generate consensus documents to standardize aspects of and provide guidelines for oncologic pathology. Consensus is established through review of relevant peer-reviewed literature relative to a subgroup's particular focus. In this document, the authors provide descriptions of the literature reviewed, the review process, and a summary of the information gathered on immunocytochemistry. The intent of this publication is to help educate practitioners and pathologists on the process of immunocytochemistry and to provide a guide for the use of this technique in veterinary medicine. This document represents the opinions of the working group and the authors and does not constitute a formal endorsement by the American College of Veterinary Pathologists or the Veterinary Cancer Society.


Assuntos
Imuno-Histoquímica/veterinária , Neoplasias/veterinária , Patologia Veterinária/métodos , Animais , Anticorpos/imunologia , Imuno-Histoquímica/métodos , Imuno-Histoquímica/tendências , Neoplasias/imunologia , Neoplasias/patologia , Patologia Veterinária/tendências , Guias de Prática Clínica como Assunto
3.
J Comp Pathol ; 156(1): 37-41, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28011041

RESUMO

The pathogenesis of canine T-cell lymphoma remains incompletely understood, partly because there are no well-established in-vivo models to study these malignancies. For this study, we generated a patient-derived tumour xenograft (PDTX) from a 10-year-old neutered male golden retriever dog with enteropathy-associated intestinal T-cell lymphoma, large cell type. One of two female, 15-week-old beige/nude/XID mice developed a visible tumour 7 weeks after sections of tumour material from the spleen were surgically implanted. The histological appearance, immunophenotype and clonal antigen receptor rearrangements of the tumour from the recipient mouse showed that it was derived from the primary canine tumour. Our results indicate that immunodeficient mice are receptive hosts to develop in-vivo PDTX models to study the pathogenesis and management of canine T-cell lymphomas.


Assuntos
Modelos Animais de Doenças , Doenças do Cão , Linfoma de Células T Associado a Enteropatia/veterinária , Animais , Cães , Feminino , Xenoenxertos , Masculino , Camundongos , Camundongos Nus
4.
Vet Pathol ; 52(1): 107-19, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24577721

RESUMO

Chronic wasting disease (CWD) is an efficiently transmitted, fatal, and progressive prion disease of cervids with an as yet to be fully clarified host range. While outbred domestic cats (Felis catus) have recently been shown to be susceptible to experimental CWD infection, the neuropathologic features of the infection are lacking. Such information is vital to provide diagnostic power in the event of natural interspecies transmission and insights into host and strain interactions in interspecies prion infection. Using light microscopy and immunohistochemistry, we detail the topographic pattern of neural spongiosis (the "lesion profile") and the distribution of misfolded prion protein in the primary and secondary passage of feline CWD (Fel(CWD)). We also evaluated cellular and subcellular associations between misfolded prion protein (PrP(D)) and central nervous system neurons and glial cell populations. From these studies, we (1) describe the novel neuropathologic profile of Fel(CWD), which is distinct from either cervid CWD or feline spongiform encephalopathy (FSE), and (2) provide evidence of serial passage-associated interspecies prion adaptation. In addition, we demonstrate through confocal analysis the successful co-localization of PrP(D) with neurons, astrocytes, microglia, lysosomes, and synaptophysin, which, in part, implicates each of these in the neuropathology of Fel(CWD). In conclusion, this work illustrates the simultaneous role of both host and strain in the development of a unique Fel(CWD) neuropathologic profile and that such a profile can be used to discriminate between Fel(CWD) and FSE.


Assuntos
Doenças do Gato/patologia , Príons/fisiologia , Doença de Emaciação Crônica/patologia , Animais , Astrócitos/metabolismo , Astrócitos/patologia , Doenças do Gato/metabolismo , Gatos , Sistema Nervoso Central/metabolismo , Sistema Nervoso Central/patologia , Neurônios/metabolismo , Neurônios/patologia , Inoculações Seriadas/veterinária , Sinaptofisina/metabolismo
5.
J Vet Intern Med ; 28(3): 878-86, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24655022

RESUMO

BACKGROUND: Canine T-cell lymphoma (TCL) is clinically and histologically heterogeneous with some forms, such as T-zone lymphoma (TZL), having an indolent course. Immunophenotyping is an important tool in the classification of TCL in people, and can be equally useful in dogs. HYPOTHESIS/OBJECTIVES: We hypothesized that loss of expression of the CD45 antigen is a specific diagnostic feature of TZL. ANIMALS: Twenty dogs with concurrent histology and immunophenotyping by flow cytometry were studied in depth. An additional 494 dogs diagnosed by immunophenotyping were used to characterize the population of dogs with this disease. METHODS: Lymph node biopsies from 35 dogs with TCL were classified by 2 pathologists using WHO criteria. Twenty lymph nodes were from dogs with CD45- TCL and 15 were from CD45+ TCL. The pathologists were blinded to the flow cytometry findings. Outcome information was sought for the 20 dogs with CD45- lymphoma, and population characteristics of the additional 494 dogs were described. RESULTS: All 20 CD45- cases were classified as TZL. The 15 CD45+ cases were classified as aggressive TCL and are described in an accompanying paper. TZL cases had a median survival of 637 days. Examination of 494 additional dogs diagnosed with TZL by immunophenotyping demonstrated that 40% of cases are in Golden Retrievers, are diagnosed at a median age of 10 years, and the majority have lymphadenopathy and lymphocytosis. CONCLUSIONS: TZL has unique immunophenotypic features that can be used for diagnosis.


Assuntos
Doenças do Cão/imunologia , Linfoma de Células T/veterinária , Animais , Doenças do Cão/diagnóstico , Doenças do Cão/patologia , Cães , Feminino , Citometria de Fluxo/veterinária , Imunofenotipagem , Antígenos Comuns de Leucócito/imunologia , Linfonodos/patologia , Linfoma de Células T/diagnóstico , Linfoma de Células T/imunologia , Linfoma de Células T/patologia , Masculino
6.
J Vet Intern Med ; 28(2): 538-46, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24495161

RESUMO

BACKGROUND: Canine T-cell lymphoma (TCL) is conventionally considered an aggressive disease, but some forms are histologically and clinically indolent. CD4 TCL is reported to be the most common subtype of TCL. We assessed flow cytometric characteristics, histologic features when available, and clinical outcomes of CD4+ TCL to determine if flow cytometry can be used to subclassify this group of lymphomas. OBJECTIVE: To test the hypothesis that canine CD4+ T-cell lymphoma (TCL) is a homogeneous group of lymphomas with an aggressive clinical course. ANIMALS: Sixty-seven dogs diagnosed with CD4+ TCL by flow cytometry and treated at 1 of 3 oncology referral clinics. METHODS: Retrospective multivariable analysis of outcome in canine CD4+ TCL including patient characteristics, treatment, and flow cytometric features. RESULTS: The majority of CD4+ TCL were CD45+, expressed low class II MHC, and exhibited an aggressive clinical course independent of treatment regimen (median survival, 159 days). Histologically, CD4+ TCL were classified as lymphoblastic or peripheral T cell. Size of the neoplastic lymphocytes had a modest effect on both PFI and survival in this group. A small number of CD4+ TCL were CD45- and class II MHC high, and exhibited an apparently more indolent clinical course (median survival not yet reached). CONCLUSIONS AND CLINICAL IMPORTANCE: Although the majority of CD4+ TCL in dogs had uniform clinical and flow cytometric features and an aggressive clinical course, a subset had a unique immunophenotype that predicts significantly longer survival. This finding strengthens the utility of flow cytometry to aid in the stratification of canine lymphoma.


Assuntos
Contagem de Linfócito CD4/veterinária , Doenças do Cão/sangue , Linfoma de Células T/veterinária , Animais , Antineoplásicos/uso terapêutico , Linfócitos T CD4-Positivos/patologia , Doenças do Cão/diagnóstico , Doenças do Cão/tratamento farmacológico , Doenças do Cão/patologia , Cães , Feminino , Citometria de Fluxo/veterinária , Linfoma de Células T/sangue , Linfoma de Células T/diagnóstico , Linfoma de Células T/tratamento farmacológico , Linfoma de Células T/patologia , Masculino , Estudos Retrospectivos , Resultado do Tratamento
7.
Transplant Proc ; 41(3): 916-8, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19376388

RESUMO

AIMS: To evaluate pancreas graft function, use of insulin, cholesterol, triglyceride levels, prescription of lipid-lowering drugs, and immunosuppressive regimens among recipients of simultaneous pancreas-kidney transplants (SPKT), who had initial immunosuppression with tacrolimus, sirolimus, and corticosteroids. METHODS: From 2000 to 2007, we performed 73 SKPT, among which we conducted a retrospective data analysis on 51 medical records of patients who had been followed for at least 6 to 72 months. We excluded from the analysis eight recipients who died before 6 months: eight with early pancreas graft losses and six for continued follow-up in other centers. RESULTS: There were four pancreas graft losses after 6 months due in two diabetes mellitus recurrence, one posttuberculosis treatment, and one after use of nonsteroidal inflammatory medication. Mean plasma glucose levels ranged from 84 to 103 mg/dL, while glycosylated hemoglobin (HbA1) levels ranged from 5.7% to 6.2%. At 6, 12, 36, and 60 months, 80%, 91%, 86%, and 75% of recipients, respectively, had HbA1 lower than 6.5%. In the same period, 10%, 8%, 10%, and 11% of recipients became insulin-dependent. Mean cholesterol levels (mg/dL) at 6, 12, 36, and 60 month were 190, 180, 196 and 193, while triglyceride levels (mg/dL) were 162, 129, 106, and 113 respectively. Recipient's rate of lipid-lowering drug use was 18%, 21%, 20%, and 22% at 6, 12, 36, and 60 months. Mean serum creatinine levels (mg/dL) with standard deviations were 1.3 +/- 0.4, 1.5 +/- 0.4, 1.6 +/- 0.5, 1.8 +/- 0.9, at 6, 12, 36 and 60 months respectively. Nineteen recipients had sirolimus suspended and 14 recipients, tacrolimus suspended as well for various reasons. CONCLUSION: Mean plasma glucose levels were normal during the period. About 10% of recipients became insulin-dependent and 20% required lipid-lowering drugs. The immunosuppressive regimen protocol had to be changed in 60% of patients.


Assuntos
Colesterol/sangue , Diabetes Mellitus Tipo 1/cirurgia , Nefropatias Diabéticas/cirurgia , Imunossupressores/uso terapêutico , Falência Renal Crônica/cirurgia , Transplante de Rim/fisiologia , Transplante de Pâncreas/fisiologia , Triglicerídeos/sangue , Glicemia/metabolismo , Seguimentos , Hemoglobinas Glicadas/metabolismo , Humanos , Hipolipemiantes/uso terapêutico , Transplante de Rim/imunologia , Transplante de Rim/mortalidade , Transplante de Pâncreas/imunologia , Transplante de Pâncreas/mortalidade , Seleção de Pacientes , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento
8.
Soc Neurosci ; 4(6): 518-27, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-18633835

RESUMO

Recent reports of successful fMRI-based discrimination between lie and truth in single subjects raised the interest of prospective users and a public concern about the potential scope of this technology. The increased scrutiny highlighted the lack of controlled "real life", i.e. prospective clinical trials of this technology that conform to the common standards of medical device development. The ethics of conducting such trials given the paucity of data on fMRI-based lie detection has also been questioned. To probe the potential issues of translating the laboratory research into practice, we conducted a case study in which we adapted the standard Guilty Knowledge Test (GKT), a well-established model of producing deception, to the common scenario of lying on a resume. The task consisted of questions about pertinent items on the subject's resume, three of which could be independently verified as truth (KNOWN) and three that could not be verified and were thus termed UNKNOWN. The subject had an incentive to lie on all UNKNOWN items, and on debriefing confirmed that he had done so. Data was preprocessed, masked with a priori regions of interest, thresholded, and qualitatively evaluated for consistency with the previously reported prefronto-parietal Lie > Truth pattern. Deceptive responses to two out of the three UNKNOWN items were associated with the predicted prefronto-parietal fMRI pattern. In the third UNKNOWN this pattern was absent, and instead, increased limbic (amygdala and hippocampus) response was observed. Based on published prefronto-parietal Lie response pattern, only the first two items could be categorized as Lie. If confirmed, this demonstration of amygdala and hippocampus activation in a Lie > Truth contrast illustrates the need to integrate the limbic system and its emotional and cognitive correlates into the existing model of deception. Our experiment suggests an approach to a naturalistic scenario and the research questions that need to be answered in order to set the stage for prospective clinical trials of fMRI-based lie detection.


Assuntos
Detecção de Mentiras/psicologia , Imageamento por Ressonância Magnética/métodos , Ensaios Clínicos como Assunto , Cognição/fisiologia , Interpretação Estatística de Dados , Enganação , Emoções/fisiologia , Culpa , Humanos , Processamento de Imagem Assistida por Computador , Sistema Límbico/fisiologia , Masculino , Pessoa de Meia-Idade , Lobo Parietal/fisiologia , Córtex Pré-Frontal/fisiologia
9.
Neurocase ; 14(1): 59-67, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18569732

RESUMO

We studied the cognitive basis of the functional magnetic resonance imaging (fMRI) pattern of deception in three participants performing the Concealed Information Test (CIT). In all participants, the prefrontoparietal lie activation was similar to the pattern derived from the meta-analysis (N = 40) of our previously reported fMRI CIT studies and was unchanged when the lie response was replaced with passive viewing of the target items. When lies were replaced with irrelevant responses, only the left inferior gyrus activation was common to all subjects. This study presents a systematic strategy for testing the cognitive basis of deception models, and a qualitative approach to single-subject truth-verification fMRI tests.


Assuntos
Mapeamento Encefálico/métodos , Córtex Cerebral/fisiologia , Cognição/fisiologia , Enganação , Detecção de Mentiras/psicologia , Imageamento por Ressonância Magnética/métodos , Adulto , Córtex Cerebral/anatomia & histologia , Feminino , Lobo Frontal/anatomia & histologia , Lobo Frontal/fisiologia , Lateralidade Funcional/fisiologia , Humanos , Masculino , Processos Mentais/fisiologia , Pessoa de Meia-Idade , Modelos Neurológicos , Testes Neuropsicológicos/normas , Comportamento Verbal/fisiologia
10.
Transplant Proc ; 39(2): 353-4, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17362728

RESUMO

PURPOSE: The purpose of this study was to compare the Belzer vs Custodiol solutions for cadaveric kidney perfusion in relation to delayed graft function, renal function, acute rejection episodes, and patient and graft survivals. METHODS: This randomized prospective study included 42 kidneys and 9 simultaneous kidney and pancreas recipients from December 2002 to February 2004, namely 24 in the Custodiol arm and 27 in the Belzer arm. We analyzed delayed graft function frequency, acute rejection episodes (biopsy proven), renal function (creatinine at 1, 6, and 12 months), as well as graft and patient survivals. Categorical and continuous variables were evaluated as appropriate. RESULTS: We failed to observe a difference in the immunosuppressant drug protocol, cold ischemia time, or mean recipient or donor age. The prevalence of delayed graft function was 63% among the Belzer arm, and 50% among the Custodiol arm (P = NS). The renal function was the same in both arms at 1, 6, and 12 months. The graft survival after 3 months was 94% among the Belzer group (death from sepsis), and 95% among the Custodiol group (nonfunctioning graft). At 1 year, the results were 78% among the Belzer group (4 deaths from cardiovascular or infectious complications and 2 graft losses), and 79% among the Custodiol group (3 deaths, 1 primary nonfunctioning graft, and 1 graft loss; P = NS). After 12 months follow-up, patient survival was 84% among the Belzer group, and 86% among the Custodiol group. In the first year, the incidences of biopsy-proven acute rejection episodes were 37% among the Belzer group, and 33% among the Custodiol group. CONCLUSION: Custodiol solution achieved similar results compared with Belzer solution.


Assuntos
Transplante de Rim/imunologia , Soluções para Preservação de Órgãos , Doença Aguda , Adenosina , Alopurinol , Feminino , Glucose , Glutationa , Rejeição de Enxerto/epidemiologia , Humanos , Imunossupressores/uso terapêutico , Insulina , Transplante de Rim/mortalidade , Tempo de Internação , Masculino , Manitol , Transplante de Pâncreas/imunologia , Transplante de Pâncreas/mortalidade , Complicações Pós-Operatórias/epidemiologia , Cloreto de Potássio , Procaína , Estudos Prospectivos , Rafinose , Análise de Sobrevida
11.
Proc Natl Acad Sci U S A ; 100(13): 7931-6, 2003 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-12792019

RESUMO

Both amplitude and phase of rhythmic slow-wave electroencephalographic activity are physiological correlates of learning and memory in rodents. In humans, oscillatory amplitude has been shown to correlate with memory; however, the role of oscillatory phase in human memory is unknown. We recorded intracranial electroencephalogram from human cortical and hippocampal areas while subjects performed a short-term recognition memory task. On each trial, a series of four list items was presented followed by a memory probe. We found agreement across trials of the phase of oscillations in the 7- to 16-Hz range after randomly timed stimulus events, evidence that these events either caused a phase shift in the underlying oscillation or initiated a new oscillation. Phase locking in this frequency range was not generally associated with increased poststimulus power, suggesting that stimulus events reset the phase of ongoing oscillations. Different stimulus classes selectively modulated this phase reset effect, with topographically distinct sets of recording sites exhibiting preferential reset to either probe items or to list items. These findings implicate the reset of brain oscillations in human working memory.


Assuntos
Hipocampo/fisiologia , Memória , Neocórtex/fisiologia , Lesões Encefálicas/patologia , Mapeamento Encefálico , Eletroencefalografia , Epilepsia/patologia , Hipocampo/anatomia & histologia , Humanos , Neocórtex/anatomia & histologia , Oscilometria , Fatores de Tempo
14.
Curr Opin Neurobiol ; 11(6): 739-44, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11741027

RESUMO

Recent physiological studies have implicated theta - a high-amplitude 4-8 Hz oscillation that is prominent in rat hippocampus during locomotion, orienting and other voluntary behaviors - in synaptic plasticity, information coding and the function of working memory. Intracranial recordings from human cortex have revealed evidence of high-amplitude theta oscillations throughout the brain, including the neocortex. Although its specific role is largely unknown, the observation of human theta has begun to reveal an intriguing connection between brain oscillations and cognitive processes.


Assuntos
Eletroencefalografia , Roedores/fisiologia , Animais , Hipocampo/fisiologia , Humanos , Camundongos , Ratos
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