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1.
J Immunother Cancer ; 8(2)2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33268350

RESUMO

Since the publication of the Society for Immunotherapy of Cancer's (SITC) original cancer immunotherapy biomarkers resource document, there have been remarkable breakthroughs in cancer immunotherapy, in particular the development and approval of immune checkpoint inhibitors, engineered cellular therapies, and tumor vaccines to unleash antitumor immune activity. The most notable feature of these breakthroughs is the achievement of durable clinical responses in some patients, enabling long-term survival. These durable responses have been noted in tumor types that were not previously considered immunotherapy-sensitive, suggesting that all patients with cancer may have the potential to benefit from immunotherapy. However, a persistent challenge in the field is the fact that only a minority of patients respond to immunotherapy, especially those therapies that rely on endogenous immune activation such as checkpoint inhibitors and vaccination due to the complex and heterogeneous immune escape mechanisms which can develop in each patient. Therefore, the development of robust biomarkers for each immunotherapy strategy, enabling rational patient selection and the design of precise combination therapies, is key for the continued success and improvement of immunotherapy. In this document, we summarize and update established biomarkers, guidelines, and regulatory considerations for clinical immune biomarker development, discuss well-known and novel technologies for biomarker discovery and validation, and provide tools and resources that can be used by the biomarker research community to facilitate the continued development of immuno-oncology and aid in the goal of durable responses in all patients.


Assuntos
Biomarcadores Tumorais/imunologia , Imunoterapia/métodos , Neoplasias/imunologia , Neoplasias/terapia , Humanos
2.
Environ Sci Process Impacts ; 22(2): 364-380, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31942891

RESUMO

River islands (Ait or Eyot) within the inner tidal Thames serve as unique recorders of current and historical estuarine chemical pollution. Sediment cores from Chiswick Ait were assessed for contamination using Microtox® solid phase bioassay, stable isotopes (δ13C, δ15N), heavy metals and polychlorinated biphenyls (PCBs). Microtox® classified these sediments as non-toxic to moderately toxic and bulk isotopes identified a change in organic input. Metals Cu, Zn, Cr, Ni, Cd, Hg and Ag showed parallel rise, peak and fall profiles which when allied to a 207/208Pb and 137Cs based chronology supported major changes in trace metal contributions corresponding to approximate input times of 1940 (rise), 1963 (peak) and 1985 (fall). Metals ranged from Cu 15 to 373 mg kg-1 (mean 141 mg kg-1), Zn 137 to 1331 mg kg-1 (mean 576 mg kg-1), Cr 14-351 mg kg-1 (mean 156 mg kg-1), Pb 10 to 1506 mg kg-1 (mean 402 mg kg-1), As 1 to 107 (mean 38 mg kg-1), Ni 11 to 113 mg kg-1 (mean 63 mg kg-1), Cd 0.2 to 53 mg kg-1 (mean 9 mg kg-1), Hg 1 to 8 mg kg-1 (mean 4.6 mg kg-1) and Ag from 0.7 to 50 mg kg-1 (mean 7.5 mg kg-1). Down core total PCBs ranged from 10.5 to 121 µg kg-1 and mean of 39 µg kg-1. The rise, peak and fall of Cu, Zn, Cr, Ni, Cd and Ag pollution matched local sewage works' treatment discharge records. Whereas the Hg, Pb and As profiles were disconnected, reflecting alternative historic sources and or partitioning behaviour. Comparison to marine sediment quality guidelines indicate that Zn, Pb, Ni, Cd and Hg exceed action level 2, whereas sedimentary Cu, Cr and As concentrations were above action level 1 (no action) but below action level 2 (further investigation required). The river islands of the tidal Thames capture a unique contaminant chemistry record due in part to their location in the tidal frame (salinity minimum) and close proximity to west London.


Assuntos
Metais Pesados , Bifenilos Policlorados , Poluentes Químicos da Água , China , Monitoramento Ambiental , Estuários , Sedimentos Geológicos , Londres , Metais Pesados/toxicidade , Bifenilos Policlorados/toxicidade , Rios , Poluentes Químicos da Água/toxicidade
3.
Environ Geochem Health ; 42(4): 1109-1115, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31175489

RESUMO

Understanding the risks of a developing unconventional hydrocarbons industry, including shale gas, to the chemical quality of surface water and groundwater involves firstly establishing baseline compositions against which any future changes can be assessed. Contaminants of geogenic origin are of particular interest and radon has been identified as one potential contaminant from shale sources. Robust measurement and monitoring of radon in water at environmental concentrations is essential for ensuring protection of water sources and maintaining public confidence. Traditional techniques for Rn-222 determination in water, such as inference by gamma spectrometry and direct alpha counting, are impractical for direct field measurement, and the relatively short half-life of Rn-222 (~ 3.82 days) means that longer analytical protocols from field to the laboratory may result in greater uncertainty for Rn-222 activity. Therefore, a rapid and low-cost method would be beneficial. We have developed and refined a laboratory procedure for Rn-222 monitoring using liquid scintillation counting (LSC). The accuracy of Rn-222 activities obtained via this procedure was evaluated by the analysis of almost 200 water samples collected from streams and boreholes as part of a detailed baseline investigation in the Vale of Pickering, Yorkshire, one potential location for future shale gas exploration. LSC was preferred for measurement of Rn-222 and had comparable accuracy to gamma spectrometry and direct alpha counting. The methodology provided a rapid, portable and low-maintenance option relative to the two established techniques and is shown to be a favourable choice for the measurement of radon in surface water and groundwater at environmental concentrations.


Assuntos
Água Doce/análise , Radônio/análise , Contagem de Cintilação/métodos , Poluentes Radioativos da Água/análise , Água Subterrânea/análise , Monitoramento de Radiação , Rios , Espectrometria gama/métodos , Reino Unido
4.
J Vet Intern Med ; 32(1): 394-405, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29194765

RESUMO

BACKGROUND: KIT inhibitors, such as toceranib (TOC), and vinblastine (VBL) have not been prospectively compared in the treatment of macroscopic mast cell tumors (MCTs). Also, it is unknown whether VBL or TOC is superior for treating MCT without c-kit mutations. HYPOTHESIS/OBJECTIVES: To determine the value of KIT genotyping and localization in treatment decisions for dogs with macroscopic MCT. We hypothesized that c-kit mutated MCT would have a better response to TOC than VBL. ANIMALS: Eighty-eight client-owned dogs with macroscopic MCT. METHODS: Prospective, randomized trial. Dogs were randomized to TOC (2.75 mg/kg EOD) or VBL (2.5 mg/m2 weekly × 4 then EOW) by KIT localization and c-kit mutation status using an adaptive randomization scheme. RESULTS: Sixty dogs were allocated to TOC and 28 to VBL. Of the dogs receiving TOC, 20% had c-kit mutations, compared to 30% receiving VBL (P = 0.74). Overall response rates were 46% (TOC) and 30% (VBL) (odds ratio = 1.56 [0.62-3.92]; P = 0.28). Median progression-free survival (PFS) for dogs receiving VBL was 78 days (7-1,521) and for TOC 95.5 (14-990); hazard ratio (HR) = 1.34 [0.72-2.50]; P = 0.36. Median overall survival (OS) was 241.5 days (10-1,521) for the VBL group and 159 (20-990) for the TOC group; HR = 0.80 ([0.45-1.41]; P = 0.44). CONCLUSIONS AND CLINICAL IMPORTANCE: Neither PFS nor OS was significantly different between treatment groups. As the proportion of dogs with c-kit mutations was not different between treatment groups in this population of dogs, c-kit mutation status did not predict treatment response.


Assuntos
Doenças do Cão/tratamento farmacológico , Indóis/uso terapêutico , Mastocitose Cutânea/veterinária , Prednisona/uso terapêutico , Proteínas Proto-Oncogênicas c-kit/genética , Pirróis/uso terapêutico , Vimblastina/uso terapêutico , Animais , Antineoplásicos/uso terapêutico , Intervalo Livre de Doença , Cães , Feminino , Masculino , Mastocitose Cutânea/tratamento farmacológico , Mastocitose Cutânea/genética , Mutação , Estudos Prospectivos
5.
Vet Pathol ; 54(3): 387-394, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28129097

RESUMO

Canine cutaneous mast cell tumor (MCT) is the most common canine skin tumor and exhibits variable biologic behavior. Signaling through the KIT receptor tyrosine kinase promotes cellular proliferation and survival and has been shown to play a role in MCT progression. Despite investigations into numerous biomarkers and the proposal of several grading schemas, no single marker or grading system can accurately predict outcome in canine MCT. The first aim of this study was to develop an immunohistochemical assay to measure phosphorylated KIT (pKIT) to investigate its association with 2 commonly used grading systems and other established prognostic markers for canine MCT. Thirty-four archived MCTs were evaluated for expression of pKIT and Ki-67, KIT localization, mitotic count, mutations in exons 8 and 11 in c-kit, and grading by the Patnaik and 2-tier systems. Expression of pKIT was significantly ( P < .05) correlated with the 2-tier grading scheme and c-kit mutation. Correlation approached significance ( P = .06) with Mitotic Index (MI) and Ki-67. An additional aim was to determine whether pKIT labeling provides a pharmacodynamic marker for predicting response to the receptor tyrosine kinase inhibitor toceranib (TOC). MCTs from 4 of 7 patients demonstrated a partial response to TOC. pKIT expression was assessed by immunohistochemistry in biopsies obtained before and 6 hours after the patients were treated with TOC. Reduced pKIT expression after TOC treatment was demonstrated in 3 of the 4 patients with a partial response compared to 1 of the 3 nonresponders. Collectively, these results demonstrate that immunohistochemical detection of pKIT may be a clinically relevant assay to evaluate the activation status of the major oncogenic pathway in canine MCT.


Assuntos
Doenças do Cão/patologia , Mastocitose Cutânea/veterinária , Proteínas Proto-Oncogênicas c-kit/metabolismo , Animais , Biomarcadores , Doenças do Cão/diagnóstico , Cães , Mastocitose Cutânea/diagnóstico , Mastocitose Cutânea/patologia , Fosforilação , Prognóstico , Estudos Retrospectivos
6.
Vet Comp Oncol ; 14(4): 371-383, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25212092

RESUMO

Feline oral squamous cell carcinoma (SCC) has very poor prognosis. Here, a retrospective pilot study was conducted on 20 feline oral SCC patients who underwent stereotactic radiation therapy (SRT), to evaluate: (1) the value of putative tumour initiating cell (TIC) markers of human head and neck SCC (CD44, Bmi-1); (2) telomere length (TL) specifically in putative TICs; and (3) tumour relative telomerase activity (TA). Significant inverse correlations were found between treatment outcomes and Bmi-1 expression, supporting the predictive value of Bmi-1 as a negative prognostic indicator. While TL exhibited a wide range of variability, particularly in very short fractions, many tumours possessed high levels of TA, which correlated with high levels of Bmi-1, Ki67 and EGFR. Taken together, our results imply that Bmi-1 and telomerase may represent novel therapeutic targets in feline oral SCC, as their inhibition - in combination with SRT - would be expected to have beneficial treatment outcome.


Assuntos
Carcinoma de Células Escamosas/veterinária , Doenças do Gato/patologia , Neoplasias Bucais/veterinária , Células-Tronco Neoplásicas/patologia , Telomerase/metabolismo , Animais , Biomarcadores Tumorais , Carcinoma de Células Escamosas/patologia , Doenças do Gato/terapia , Gatos , Feminino , Masculino , Neoplasias Bucais/patologia , Valor Preditivo dos Testes , Telômero
7.
Vet Comp Oncol ; 14(2): e45-57, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24923332

RESUMO

Canine lymphoma (LSA) and osteosarcoma (OS) have high mortality rates and remain in need of more effective therapeutic approaches. Survivin, an inhibitor of apoptosis (IAP) family member protein that inhibits apoptosis and drives cell proliferation, is commonly elevated in human and canine cancer. Survivin expression is a negative prognostic factor in dogs with LSA and OS, and canine LSA and OS cell lines express high levels of survivin. In this study, we demonstrate that survivin downregulation in canine LSA and OS cells using a clinically applicable locked nucleic acid antisense oligonucleotide (EZN-3042, Enzon Pharmaceuticals, Piscataway Township, NJ, USA) inhibits growth, induces apoptosis and enhances chemosensitivity in vitro, and inhibits survivin transcription and protein production in orthotopic canine OS xenografts. Our findings strongly suggest that survivin-directed therapies might be effective in treatment of canine LSA and OS and support evaluation of EZN-3042 in dogs with cancer.


Assuntos
Apoptose/efeitos dos fármacos , Doenças do Cão/metabolismo , Proteínas Inibidoras de Apoptose/antagonistas & inibidores , Linfoma/veterinária , Oligonucleotídeos/farmacologia , Osteossarcoma/veterinária , Animais , Linhagem Celular Tumoral , Doenças do Cão/tratamento farmacológico , Cães , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Proteínas Inibidoras de Apoptose/metabolismo , Linfoma/tratamento farmacológico , Camundongos , Neoplasias Experimentais/tratamento farmacológico , Osteossarcoma/tratamento farmacológico , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
8.
Vet Comp Oncol ; 14(1): 39-57, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23815402

RESUMO

This study evaluated molecular characteristics that are potentially prognostic in cats with oral squamous cell carcinoma (SCC) that underwent stereotactic radiation therapy (SRT). Survival time (ST) and progression-free interval (PFI) were correlated with mitotic index, histopathological grades, Ki67 and epidermal growth factor receptor expressions, tumour microvascular density (MVD), and tumour oxygen tension (pO(2)). Median ST and PFI were 106 and 87 days, respectively (n = 20). Overall response rate was 38.5% with rapid improvement of clinical symptoms in many cases. Patients with higher MVD or more keratinized SCC had significantly shorter ST or PFI than patients with lower MVD or less keratinized SCC (P = 0.041 and 0.049, respectively). Females had significantly longer PFI and ST than males (P ≤ 0.016). Acute toxicities were minimal. However, treatment-related complications such as fractured mandible impacted quality of life. In conclusion, SRT alone should be considered as a palliative treatment. MVD and degree of keratinization may be useful prognostic markers.


Assuntos
Carcinoma de Células Escamosas/veterinária , Doenças do Gato/radioterapia , Neoplasias Bucais/veterinária , Técnicas Estereotáxicas/veterinária , Animais , Carcinoma de Células Escamosas/radioterapia , Gatos , Receptores ErbB/genética , Receptores ErbB/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Imuno-Histoquímica , Antígeno Ki-67/genética , Antígeno Ki-67/metabolismo , Masculino , Neoplasias Bucais/radioterapia , Consumo de Oxigênio , Prognóstico , Análise de Sobrevida
9.
Vet Comp Oncol ; 14(3): 236-44, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24593773

RESUMO

Lymphangiosarcomas are uncommon vascular neoplasms that arise from lymphatic endothelial cells (LECs). They efface and replace normal subcutaneous tissue and are characterised by arborising, vascular channels lined by a single layer of pleomorphic endothelial cells and a paucity of erythrocytes. Lymphangiosarcomas are architecturally similar to hemangiosarcomas, a common malignancy of vascular origin arising from blood vascular endothelial cells. Common immunohistochemical markers for vascular endothelium, such as Factor VIII-related antigen (F8RA) and CD31, have traditionally been used to confirm the diagnosis of tumours of vascular origin. However, these markers fail to differentiate between lymphangiosarcoma and hemangiosarcoma, which often show overlapping morphologic features, disparate clinical behaviour and require different treatment modalities. Here we describe the use of two novel LEC-specific markers, lymphatic vessel endothelial receptor-1 (LYVE-1) and prospero-related homeobox gene-1 (PROX-1), to further differentiate between vascular tumours of lymphatic (lymphangiosarcoma) and blood (hemangiosarcoma) endothelial cell origin in the dog.


Assuntos
Doenças do Cão/classificação , Células Endoteliais/metabolismo , Hemangiossarcoma/veterinária , Proteínas de Homeodomínio/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Neoplasias Vasculares/veterinária , Proteínas de Transporte Vesicular/metabolismo , Animais , Anticorpos , Biomarcadores Tumorais , Doenças do Cão/metabolismo , Cães , Regulação Neoplásica da Expressão Gênica/fisiologia , Hemangiossarcoma/classificação , Proteínas de Homeodomínio/genética , Proteínas Supressoras de Tumor/genética , Neoplasias Vasculares/diagnóstico , Neoplasias Vasculares/metabolismo , Proteínas de Transporte Vesicular/genética
10.
Vet Pathol ; 49(5): 771-4, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21900543
11.
Cancer Res ; 72(1): 249-59, 2012 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-22068035

RESUMO

Osteosarcoma has a high mortality rate and remains in need of more effective therapeutic approaches. Survivin is an inhibitor of apoptosis family member protein that blocks apoptosis and drives proliferation in human cancer cells where it is commonly elevated. In this study, we illustrate the superiority of a canine osteosarcoma model as a translational tool for evaluating survivin-directed therapies, owing to the striking similarities in gross and microscopic appearance, biologic behavior, gene expression, and signaling pathway alterations. Elevated survivin expression in primary canine osteosarcoma tissue correlated with increased histologic grade and mitotic index and a decreased disease-free interval (DFI). Survivin attenuation in canine osteosarcoma cells inhibited cell-cycle progression, increased apoptosis, mitotic arrest, and chemosensitivity, and cooperated with chemotherapy to significantly improve in vivo tumor control. Our findings illustrate the utility of a canine system to more accurately model human osteosarcoma and strongly suggest that survivin-directed therapies might be highly effective in its treatment.


Assuntos
Neoplasias Ósseas/veterinária , Proteínas de Neoplasias/metabolismo , Osteossarcoma/veterinária , Animais , Apoptose , Neoplasias Ósseas/metabolismo , Neoplasias Ósseas/patologia , Linhagem Celular Tumoral , Modelos Animais de Doenças , Cães , Imunofluorescência , Inativação Gênica , Camundongos , Proteínas de Neoplasias/fisiologia , Osteossarcoma/metabolismo , Osteossarcoma/patologia , RNA Interferente Pequeno , Reação em Cadeia da Polimerase Via Transcriptase Reversa
12.
Vet Pathol ; 49(4): 693-703, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21712517

RESUMO

Immunohistochemistry allows the localization of proteins to specific regions of the nephron. This article reports the identification and localization of proteins in situ within normal canine, feline, and mouse kidney by immunohistochemistry; maps their distribution; and compares results to previously reported findings in other species. The proteins investigated are aquaporin 1, aquaporin 2, calbindin D-28k, glutathione S-transferase-α, and Tamm-Horsfall protein. Aquaporins are integral membrane proteins involved in water transport across cell membranes. Calbindin D-28k is involved in renal calcium metabolism. Glutathione S-transferase-α is a protein that aids in detoxification and drug metabolism. The role of Tamm-Horsfall protein is not fully understood. Proposed functions include inhibition of calcium crystallization and reduction of bacterial urinary tract infection. The authors' findings in the dog are similar to those in other species: Specifically, the authors localize aquaporin 1 to the proximal convoluted tubule epithelium, vasa recta endothelium, and descending thin limbs; aquaporin 2 to collecting duct epithelium; and calbindin D-28k within distal convoluted tubule epithelium. Glutathione S-transferase-α has variable expression and is found in only the renal transitional epithelium in some individuals, in only the proximal straight tubules in others, or in both locations in others. Tamm-Horsfall protein localizes to thick ascending limb epithelium. These findings are similar in the cat, with the exception that aquaporin 1 is located in glomerular podocytes, in addition to proximal convoluted tubule epithelium, and glutathione S-transferase-α is found solely within the proximal convoluted tubule within all kidney samples examined. The mouse kidney is almost identical to the dog but expresses glutathione S-transferase-α in the glomeruli only.


Assuntos
Gatos/fisiologia , Cães/fisiologia , Rim/metabolismo , Proteínas de Membrana/metabolismo , Camundongos/fisiologia , Transporte Proteico/fisiologia , Animais , Regulação da Expressão Gênica/fisiologia , Proteínas de Membrana/genética
13.
Vet Pathol ; 45(6): 825-8, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18984785

RESUMO

The enzyme cyclooxygenase-2 (COX-2) is expressed in some tumor and stromal tissues, and catalyzes production of prostaglandins with growth stimulatory, antiapoptotic, proangiogenic, and immunosuppressive properties. Pharmacologic inhibition of COX-2 is associated with antitumor activity in various human and canine malignancies. The purpose of this study was to assess COX-2 expression in a series of equine sarcoids, melanomas, and squamous-cell carcinomas (SCC). COX-2 expression was assessed in formalin-fixed paraffin-embedded tissues from 14 sarcoids, 11 melanomas, and 37 SCC that represent various anatomic sites by using standard immunohistochemical methods. COX-2 was expressed in 2 of 14 sarcoids, 7 of 11 melanomas, and 32 of 37 SCC, 56% of which demonstrated moderate-to-strong immunoreactivity. There were no differences in expression between anatomic sites. In conclusion, most equine SCC and many melanomas appear to express COX-2 and thus could respond to COX-2 inhibitor therapy.


Assuntos
Ciclo-Oxigenase 2/metabolismo , Doenças dos Cavalos/enzimologia , Neoplasias/veterinária , Animais , Ciclo-Oxigenase 2/genética , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Cavalos , Neoplasias/enzimologia
14.
J Vet Intern Med ; 22(4): 989-95, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18647159

RESUMO

BACKGROUND: Survivin, a member of the inhibitor of apoptosis protein family, has a dual role in tumor cell proliferative and antiapoptotic pathways. Survivin expression has been shown to be a negative prognostic factor in several cancers of humans, including B-cell non-Hodgkin's lymphoma. HYPOTHESES: High survivin expression will be a negative prognostic factor in dogs with lymphoma (LSA) treated with chemotherapy. In addition, survivin expression will be upregulated in relapsed canine LSA when compared with patient-matched, pretreatment biopsies. ANIMALS: Thirty-one client-owned dogs with stage IIIa or IVa LSA. METHODS: Retrospective evaluation of survivin immunoreactivity was performed on pretreatment lymph node biopsies and patient-matched samples obtained from dogs at relapse after being treated with an abbreviated CHOP-based protocol. RESULTS: In this population of dogs presenting with stage IIIa or IVa B-cell LSA, those dogs that had high survivin immunoreactivity scores had a significantly (P < .01, hazard ratio = 0.30) shorter median disease-free interval than did dogs with low survivin immunoreactivity scores (171 days versus 321 days, respectively). Survivin immunoreactivity was not significantly different in relapsed canine LSA when compared with patient-matched, pretreatment biopsies. CONCLUSIONS AND CLINICAL IMPORTANCE: Survivin expression is a negative prognostic factor that can predict early treatment failure of dogs that present with stage IIIa or IVa, B-cell LSA when treated with a CHOP-based protocol.


Assuntos
Doenças do Cão/metabolismo , Linfoma/veterinária , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas de Neoplasias/metabolismo , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Ciclofosfamida/uso terapêutico , Doenças do Cão/tratamento farmacológico , Cães , Doxorrubicina/uso terapêutico , Feminino , Regulação Neoplásica da Expressão Gênica , Linfoma/tratamento farmacológico , Linfoma/metabolismo , Masculino , Proteínas Associadas aos Microtúbulos/genética , Proteínas de Neoplasias/genética , Prednisona/uso terapêutico , Recidiva , Fatores de Tempo , Vincristina/uso terapêutico
15.
Vet Comp Oncol ; 6(2): 133-40, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19178673

RESUMO

Hypoxia in tumours has been associated with an increased resistance to radiation and chemotherapy, and increased metastatic potential. Hypoxia-inducible factor 1-alpha (HIF-1alpha) is a transcription factor induced by hypoxia. Glucose transporter 1 (GLUT-1), a downstream product of HIF-1alpha pathway activation, is over-expressed in a variety of human tumours. The purpose of this study was to determine if GLUT-1 is expressed in canine osteosarcomas (OSAs) and if the expression is related to tumour necrosis and outcome. Immunohistochemistry was performed on 44 histologically confirmed OSA tissue samples to assess expression of GLUT-1. Of 44 cases, 27 (61%) expressed GLUT-1. There was no statistical correlation between GLUT-1 and disease-free interval, survival time or percentage of necrosis. As hypothesized, GLUT-1 is present in canine appendicular OSAs. A more objective evaluation of GLUT-1 and other proteins in the HIF-1alpha pathway may be warranted.


Assuntos
Neoplasias Ósseas/veterinária , Doenças do Cão/metabolismo , Transportador de Glucose Tipo 1/metabolismo , Osteossarcoma/veterinária , Animais , Biomarcadores Tumorais/sangue , Neoplasias Ósseas/metabolismo , Neoplasias Ósseas/patologia , Intervalo Livre de Doença , Doenças do Cão/patologia , Cães , Feminino , Regulação Neoplásica da Expressão Gênica , Subunidade alfa do Fator 1 Induzível por Hipóxia , Imuno-Histoquímica/veterinária , Masculino , Necrose , Osteossarcoma/metabolismo , Osteossarcoma/patologia , Prognóstico , Resultado do Tratamento
16.
Adv Space Res ; 31(1): 7-16, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12577893

RESUMO

Today, the tools are in our hands to enable us to travel away from our home planet and become citizens of the solar system. Even now, we are seriously beginning to develop the robust infrastructure that will make the 21st century the Century of Space Travel. But this bold step must be taken with due concern for the health, safety and wellbeing of future space explorers. Our long experience with space biomedical research convinces us that, if we are to deal effectively with the medical and biomedical issues of exploration, then dramatic and bold steps are also necessary in this field. We can no longer treat the human body as if it were composed of muscles, bones, heart and brain acting independently. Instead, we must lead the effort to develop a fully integrated view of the body, with all parts connected and fully interacting in a realistic way. This paper will present the status of current (2000) plans by the National Space Biomedical Research Institute to initiate research in this area of integrative physiology and medicine. Specifically, three example projects are discussed as potential stepping stones towards the ultimate goal of producing a digital human. These projects relate to developing a functional model of the human musculoskeletal system and the heart.


Assuntos
Fenômenos Fisiológicos Cardiovasculares , Marte , Modelos Biológicos , Fenômenos Fisiológicos Musculoesqueléticos , Voo Espacial , Ausência de Peso , Adaptação Fisiológica , Medicina Aeroespacial , Simulação por Computador , Ergonomia , Humanos , Modelos Anatômicos , Músculo Esquelético/fisiologia
17.
Med Sci Sports Exerc ; 33(1): 75-80, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11194115

RESUMO

UNLABELLED: Previous investigators have suggested that maximal exercise performed 24 h before the end of bed rest, a spaceflight analog, restores prebed rest plasma volume, baroreflex responses, and orthostatic tolerance. PURPOSE: In this case report, we examined the effect of a similar exercise protocol 24 h before a Shuttle landing on the orthostatic responses of four crewmembers (EX) after spaceflights of 8-14 d. Four additional crewmembers (CON) served as controls and did not perform exercise during the final day of the flight. METHODS: Each crewmember performed a 10-min stand test approximately 10 d before launch (L-10) and within 1-2 h of landing (R+0). Cardiac stroke volume was measured (Doppler ultrasound) supine and during each min of standing for three EX and three CON subjects. RESULTS: Preflight, all crewmembers completed the stand test and each group had similar heart rate and blood pressure responses. Postflight, all subjects also completed the 10-min stand test. Each group had similarly elevated supine and standing heart rates, elevated diastolic and mean arterial blood pressures, and reduced pulse pressures compared to L-10. However, postflight cardiac output, mean +/- SEM, (EX: 4.5+/-0.6 L x min(-1); CON: 3.1+/-0.3 L x min(-1)) and stroke volume (EX: 43+/-7 mL x beat; CON: 30+/-6 mL x beat) were higher after 10 min standing in the EX subjects compared to CON subjects. CONCLUSIONS: For these four crewmembers, maximal exercise performed 24 h before landing may have helped maintain stroke volume but did not maintain heart rate and blood pressure responses during standing compared to preflight.


Assuntos
Exercício Físico/fisiologia , Hipotensão Ortostática/prevenção & controle , Voo Espacial , Adulto , Feminino , Humanos , Masculino , Estados Unidos
19.
J Cardiovasc Diagn Proced ; 14(2): 53-7, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-11539935

RESUMO

This article presents selected findings obtained with Holter monitoring from two crew members of the expedition, performed during a 175-day space mission on board orbital space station "MIR." Using mathematical processing of daily cardiointervals files, 5-minute sections of records were analyzed consecutively. Then, the average daily values of indices, the average-per-every-eight-hours values (morning, evening, night) and mean values per hour were computed. The results of analysis showed that prolonged exposure of man to microgravity conditions leads to important functional alteration in human neuroautonomic regulatory mechanisms. Both crew members had significant increase of heart rate, the rise of stress index, the decrease in power of the spectrum in the range of respiratory sinus arrhythmia. These marked signs of activation of the sympathetic section of the vegetative nervous system showed individual variations. The analysis of the daily collection of cardiointervals with Holter monitoring allows us to understand and forecast the functional feasibilities of the human organism under a variety of stress conditions associated with acute and chronic microgravity exposure.


Assuntos
Adaptação Fisiológica , Eletrocardiografia Ambulatorial , Frequência Cardíaca , Voo Espacial , Estresse Fisiológico , Ausência de Peso , Medicina Aeroespacial , Arritmia Sinusal/fisiopatologia , Humanos , Masculino , Sistema Nervoso Parassimpático , Sistema Nervoso Simpático , Fatores de Tempo
20.
Am J Cardiol ; 79(8): 1153-5, 1997 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-9114789

RESUMO

This study represents the first systematic evaluation of dysrhythmias before, during, and after spaceflight including extravehicular activity (EVA). The data, based on 7 Shuttle crew members, revealed a nonsignificant decrease in ventricular and supraventricular ectopy during EVA, suggesting that the incidence of dysrhythmias is no greater during EVA than with any other phase of a mission or preflight.


Assuntos
Arritmias Cardíacas/fisiopatologia , Voo Espacial , Adulto , Eletrocardiografia Ambulatorial , Feminino , Humanos , Incidência , Masculino , Índice de Gravidade de Doença , Astronave , Ausência de Peso
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