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1.
New Phytol ; 233(2): 966-982, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34699614

RESUMO

The pathways regulated in ectomycorrhizal (EcM) plant hosts during the establishment of symbiosis are not as well understood when compared to the functional stages of this mutualistic interaction. Our study used the EcM host Eucalyptus grandis to elucidate symbiosis-regulated pathways across the three phases of this interaction. Using a combination of RNA sequencing and metabolomics we studied both stage-specific and core responses of E. grandis during colonization by Pisolithus microcarpus. Using exogenous manipulation of the abscisic acid (ABA), we studied the role of this pathway during symbiosis establishment. Despite the mutualistic nature of this symbiosis, a large number of disease signalling TIR-NBS-LRR genes were induced. The transcriptional regulation in E. grandis was found to be dynamic across colonization with a small core of genes consistently regulated at all stages. Genes associated to the carotenoid/ABA pathway were found within this core and ABA concentrations increased during fungal integration into the root. Supplementation of ABA led to improved accommodation of P. microcarpus into E. grandis roots. The carotenoid pathway is a core response of an EcM host to its symbiont and highlights the need to understand the role of the stress hormone ABA in controlling host-EcM fungal interactions.


Assuntos
Eucalyptus , Micorrizas , Ácido Abscísico/metabolismo , Ácido Abscísico/farmacologia , Basidiomycota , Eucalyptus/microbiologia , Micorrizas/fisiologia , Raízes de Plantas/metabolismo , Simbiose/fisiologia
2.
Am J Clin Hypn ; 64(2): 87-89, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34723768

Assuntos
Hipnose , Humanos
3.
Animals (Basel) ; 11(3)2021 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-33801097

RESUMO

The pathogenesis of steatitis that infrequently occurs in cold-stunned Kemp's ridley sea turtles (KRT; Lepidochelys kempii) has been undetermined. The objectives of this study were to investigate the clinical (n = 23) and histologic findings (n = 11) in cold-stunned KRT, and to compare plasma concentrations of α-tocopherol (vitamin E), thiobarbituric acid reactive substances (TBARS), and the TBARS to vitamin E (T/E) ratio (an assessment of oxidative stress) between cold-stunned KRT with clinically and/or histologically confirmed steatitis (n = 10) and free-ranging KRT (n = 9). None of the cold-stunned turtles had clinically detectable steatitis at admission, and the median number of days to diagnosis of steatitis was 71 (range 33­469). Histologic findings of affected adipose tissue included heterophilic (n = 9) and/or histiocytic (n = 5) steatitis, fat necrosis (n = 7), myonecrosis (n = 2), and intralesional bacteria (n = 6). Cold-stunned KRT had significantly lower plasma vitamin E concentrations (median = 3.5 nmol/g), lower plasma TBARS concentrations (median = 1.6 nmol/g), and higher T/E ratios (median = 0.50), than controls (62.3 nmol/g; 2.1 nmol/g; 0.03, respectively). These results suggest a multifactorial etiology for the development of steatitis in KRT during rehabilitation, including tissue injury, septicemia, and various factors resulting in imbalances of anti-/oxidative status. By highlighting the need to provide more effective vitamin E supplementation, and the need to re-assess specific components of the diet, this study may lead to reduced incidence and improved medical management of steatitis in cold-stunned sea turtles.

4.
BMC Cancer ; 17(1): 418, 2017 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-28619042

RESUMO

BACKGROUND: A high rate of glycolysis leading to elevated lactate content has been linked to poor clinical outcomes in patients with head and neck and cervical cancer treated with radiotherapy. Although the biological explanation for this relationship between lactate and treatment response remains unclear, there is a continued interest in evaluating strategies of targeting metabolism to enhance the effectiveness of radiotherapy. The goal of this study was to investigate the effect of metabolic-targeting through HIF-1α inhibition and the associated changes in glycolysis, oxygen consumption and response on the efficacy of high-dose single-fraction radiotherapy (HD-SFRT). METHODS: HIF-1α wild-type and HIF-1α knockdown FaDu and ME180 xenograft tumors were grown in the hind leg of mice that were placed in an environmental chamber and exposed to different oxygen conditions (air-breathing and hypoxia). Ex vivo bioluminescence microscopy was used to measure lactate and ATP levels and the hypoxic fraction was measured using EF5 immunohistochemical staining. The oxygen consumption rate (OCR) in each cell line in response to in vitro hypoxia was measured using an extracellular flux analyzer. Tumor growth delay in vivo was measured following HD-SFRT irradiation of 20 Gy. RESULTS: Targeting HIF-1α reduced lactate content, and increased both oxygen consumption and hypoxic fraction in these tumors after exposure to short-term continuous hypoxia. Tumors with intact HIF-1α subjected to HD-SFRT immediately following hypoxia exposure were less responsive to treatment than tumors without functional HIF-1α, and tumors irradiated under air breathing conditions regardless of HIF-1α status. CONCLUSIONS: Blocking the HIF1 response during transient hypoxic stress increased hypoxia, reduced lactate levels and enhanced response to HD-SFRT. This strategy of combining hypofractionated radiotherapy with metabolic reprogramming to inhibit anaerobic metabolism may increase the efficacy of HD-SFRT through increased oxygen consumption and complementary killing of radiosensitive and hypoxic, radioresistant cells.


Assuntos
Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Hipóxia/metabolismo , Ácido Láctico/metabolismo , Neoplasias/metabolismo , Consumo de Oxigênio , Trifosfato de Adenosina/metabolismo , Animais , Biomarcadores , Linhagem Celular Tumoral , Modelos Animais de Doenças , Metabolismo Energético/efeitos da radiação , Feminino , Técnicas de Silenciamento de Genes , Glicólise , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Camundongos , Neoplasias/patologia , Neoplasias/radioterapia , Neovascularização Patológica , Doses de Radiação , Carga Tumoral/efeitos da radiação , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Int J Radiat Oncol Biol Phys ; 94(1): 111-117, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-26547383

RESUMO

PURPOSE: Preclinical studies have shown that angiogenesis inhibition can improve response to radiation therapy (RT). The purpose of this phase 1 study was to examine the angiogenesis inhibitor sorafenib in patients with cervical cancer receiving radical RT and concurrent cisplatin (RTCT). METHODS AND MATERIALS: Thirteen patients with stage IB to IIIB cervical cancer participated. Sorafenib was administered daily for 7 days before the start of standard RTCT in patients with early-stage, low-risk disease and also during RTCT in patients with high-risk disease. Biomarkers of tumor vascularity, perfusion, and hypoxia were measured at baseline and again after 7 days of sorafenib alone before the start of RTCT. The median follow-up time was 4.5 years. RESULTS: Initial complete response was seen in 12 patients. One patient died without achieving disease control, and 4 experienced recurrent disease. One patient with an extensive, infiltrative tumor experienced pelvic fistulas during treatment. The 4-year actuarial survival was 85%. Late grade 3 gastrointestinal toxicity developed in 4 patients. Sorafenib alone produced a reduction in tumor perfusion/permeability and an increase in hypoxia, which resulted in early closure of the study. CONCLUSIONS: Sorafenib increased tumor hypoxia, raising concern that it might impair rather than improve disease control when added to RTCT.


Assuntos
Inibidores da Angiogênese/efeitos adversos , Carcinoma de Células Escamosas/terapia , Hipóxia Celular , Quimiorradioterapia/métodos , Niacinamida/análogos & derivados , Compostos de Fenilureia/efeitos adversos , Neoplasias do Colo do Útero/terapia , Inibidores da Angiogênese/administração & dosagem , Antineoplásicos/administração & dosagem , Biomarcadores , Braquiterapia/métodos , Carcinoma de Células Escamosas/irrigação sanguínea , Carcinoma de Células Escamosas/patologia , Cisplatino/administração & dosagem , Esquema de Medicação , Término Precoce de Ensaios Clínicos , Feminino , Seguimentos , Humanos , Niacinamida/administração & dosagem , Niacinamida/efeitos adversos , Oxigênio/metabolismo , Pressão Parcial , Compostos de Fenilureia/administração & dosagem , Tolerância a Radiação/efeitos dos fármacos , Sorafenibe , Fatores de Tempo , Carga Tumoral , Neoplasias do Colo do Útero/irrigação sanguínea , Neoplasias do Colo do Útero/patologia
6.
Pharmacol Res ; 102: 218-34, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26375988

RESUMO

Selenium supplement has been shown in clinical trials to reduce the risk of different cancers including lung carcinoma. Previous studies reported that the antiproliferative and pro-apoptotic activities of methylseleninic acid (MSA) in cancer cells could be mediated by inhibition of the PI3K pathway. A better understanding of the downstream cellular targets of MSA will provide information on its mechanism of action and will help to optimize its use in combination therapies with PI3K inhibitors. For this study, the effects of MSA on viability, cell cycle, metabolism, apoptosis, protein and mRNA expression, and reactive oxygen species production were analysed in A549 cells. FOXO3a subcellular localization was examined in A549 cells and in stably transfected human osteosarcoma U2foxRELOC cells. Our results demonstrate that MSA induces FOXO3a nuclear translocation in A549 cells and in U2OS cells that stably express GFP-FOXO3a. Interestingly, sodium selenite, another selenium compound, did not induce any significant effects on FOXO3a translocation despite inducing apoptosis. Single strand break of DNA, disruption of tumour cell metabolic adaptations, decrease in ROS production, and cell cycle arrest in G1 accompanied by induction of apoptosis are late events occurring after 24h of MSA treatment in A549 cells. Our findings suggest that FOXO3a is a relevant mediator of the antiproliferative effects of MSA. This new evidence on the mechanistic action of MSA can open new avenues in exploiting its antitumour properties and in the optimal design of novel combination therapies. We present MSA as a promising chemotherapeutic agent with synergistic antiproliferative effects with cisplatin.


Assuntos
Antineoplásicos/farmacologia , Núcleo Celular/metabolismo , Fatores de Transcrição Forkhead/metabolismo , Compostos Organosselênicos/farmacologia , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Células 3T3 , Animais , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/metabolismo , Ciclo Celular/efeitos dos fármacos , Linhagem Celular , Linhagem Celular Tumoral , Núcleo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Cisplatino/farmacologia , Proteína Forkhead Box O3 , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Humanos , Camundongos , Fosfatidilinositol 3-Quinases/metabolismo , Transporte Proteico/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo
7.
Carcinogenesis ; 36(4): 469-77, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25586991

RESUMO

Malignant melanoma is the most deadly form of skin cancer. There is a critical need to identify the patients that could be successfully treated by surgery alone and those that require adjuvant treatment. In this study, we demonstrate that the expression of tribbles2 (TRIB2) strongly correlates with both the presence and progression of melanocyte-derived malignancies. We examined the expression of TRIB2 in addition to 12 previously described melanoma biomarkers across three independent full genome microarray studies. TRIB2 expression was consistently and significantly increased in benign nevi and melanoma, and was highest in samples from patients with metastatic melanoma. The expression profiles for the 12 biomarkers were poorly conserved throughout these studies with only TYR, S100B and SPP1 showing consistently elevated expression in metastatic melanoma versus normal skin. Strikingly we confirmed these findings in 20 freshly obtained primary melanoma tissue samples from metastatic lesions where the expression of these biomarkers were evaluated revealing that TRIB2 expression correlated with disease stage and clinical prognosis. Our results suggest that TRIB2 is a meaningful biomarker reflecting diagnosis and progression of melanoma, as well as predicting clinical response to chemotherapy.


Assuntos
Biomarcadores Tumorais/genética , Proteínas Quinases Dependentes de Cálcio-Calmodulina/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Melanoma/genética , Neoplasias Cutâneas/genética , Bases de Dados Factuais , Progressão da Doença , Humanos , Melanoma/diagnóstico , Osteopontina/biossíntese , Prognóstico , Curva ROC , Subunidade beta da Proteína Ligante de Cálcio S100/biossíntese , Neoplasias Cutâneas/diagnóstico , Melanoma Maligno Cutâneo
8.
Biologicals ; 40(5): 369-81, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22884673

RESUMO

Potency testing of most human and veterinary rabies vaccines requires vaccination of mice followed by a challenge test using an intracerebral injection of live rabies virus. NICEATM, ICCVAM, and their international partners organized a workshop to review the availability and validation status of alternative methods that might reduce, refine, or replace the use of animals for rabies vaccine potency testing, and to identify research and development efforts to further advance alternative methods. Workshop participants agreed that general anesthesia should be used for intracerebral virus injections and that humane endpoints should be used routinely as the basis for euthanizing animals when conducting the mouse rabies challenge test. Workshop participants recommended as a near-term priority replacement of the mouse challenge with a test validated to ensure potency, such as the mouse antibody serum neutralization test for adjuvanted veterinary rabies vaccines for which an international collaborative study was recently completed. The workshop recommended that an in vitro antigen quantification test should be a high priority for product-specific validation of human and non-adjuvanted veterinary rabies vaccines. Finally, workshop participants recommended greater international cooperation to expedite development, validation, regulatory acceptance, and implementation of alternative test methods for rabies vaccine potency testing.


Assuntos
Alternativas aos Testes com Animais , Avaliação Pré-Clínica de Medicamentos/métodos , Avaliação Pré-Clínica de Medicamentos/tendências , Vacina Antirrábica , Alternativas aos Testes com Animais/métodos , Alternativas aos Testes com Animais/organização & administração , Animais , Educação/organização & administração , Educação em Veterinária/métodos , Planejamento em Saúde/tendências , Humanos , Cooperação Internacional , Camundongos , Raiva/imunologia , Raiva/veterinária , Vacina Antirrábica/farmacologia , Vacina Antirrábica/normas , Vacina Antirrábica/uso terapêutico , Pesquisa/tendências , Relatório de Pesquisa , Ciência/tendências , Vacinação/métodos , Vacinação/veterinária
9.
Am J Clin Hypn ; 53(1): 27-46, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20718241

RESUMO

In a 2008 pilot study we used DNA microarrays to explore the historical ideo-plastic faculty of therapeutic hypnosis. We documented how to measure changes in activity or experience-dependent gene expression over relatively brief time periods (1 hour and 24 hours) following a single intervention of therapeutic hypnosis (about 1 hour). In the present paper we utilize bioinformatic software to explore the possible meaning and significance of this ideo-plastic faculty of therapeutic hypnosis. Indications suggest that the ideo-plastic process of therapeutic hypnosis may be associated with (1) the heightening of a molecular-genomic signature for the up-regulation (heightened activity) of genes characteristic of stem cell growth, (2) a reduction in cellular oxidative stress, and (3) a reduction in chronic inflammation. We identify these three empirical associations as an initial beta version of the molecular-genomic signature of the ideo-plastic process of therapeutic hypnosis, which can serve as a theoretical and practical guide for clinical excellence by beginners as well as senior professionals. We propose this molecular-genomic level of discourse as a supplement to the traditional cognitive-behavioral description of therapeutic suggestion, hypnosis, and psychotherapy that is consistent with "translational research" currently funded by the National Institute of Mental Health (NIMH).


Assuntos
Biologia Computacional , Regulação da Expressão Gênica/genética , Hipnose/métodos , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Software , Encéfalo/metabolismo , Terapia Cognitivo-Comportamental , Perfilação da Expressão Gênica , Pesquisa em Genética , Humanos , Inflamação/genética , Plasticidade Neuronal/genética , Estresse Oxidativo , Células-Tronco/fisiologia , Pesquisa Translacional Biomédica , Regulação para Cima/genética
10.
Proc Nutr Soc ; 68(1): 98-102, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19040782

RESUMO

Companion animals represent an under-utilised resource. The present paper is designed to encourage collaborative studies. Dogs and cats are out-bred animals that are willing to consume a consistent diet for long periods, so are ideal candidates for prospective studies of naturally-occurring disease. In some studies the effect of diet on survival has been substantial. Food restriction, for example, slows the development of osteoarthritis and increases the lifespan of Labrador retrievers by 2 years, protein and P restriction more than doubles the median survival time of dogs and cats with chronic kidney disease and adding n-3 fats and arginine to the diet of dogs with stage 3 lymphoma improves median survival time by one-quarter. Obesity is also very common in both dogs and cats and is also associated with disease as in human subjects. When interpreting these results, however, it is essential to take into account pathophysiological differences among species. Dogs and cats do not display all the characteristics of metabolic disease in human subjects, they metabolise fat well and atherosclerosis and cardiac infarction are uncommon. Such differences should not, however, preclude further study because differences among species often clarify knowledge. Monitoring of disease in companion animals may also provide a surveillance system for the safety of the food supply, as illustrated by recent outbreaks of acute renal failure and liver failure in cats and dogs in the USA caused respectively by melamine and mycotoxin contamination of pet foods.


Assuntos
Doenças do Gato/prevenção & controle , Dieta/veterinária , Doenças do Cão/prevenção & controle , Promoção da Saúde , Animais , Restrição Calórica/veterinária , Doenças do Gato/terapia , Gatos , Proteínas Alimentares/administração & dosagem , Doenças do Cão/terapia , Cães , Humanos , Longevidade , Modelos Animais , Osteoartrite/prevenção & controle , Osteoartrite/veterinária , Ensaios Clínicos Controlados Aleatórios como Assunto/veterinária , Especificidade da Espécie
11.
Ann Pharmacother ; 41(7): 1124-9, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17578882

RESUMO

BACKGROUND: The majority of Canadians use natural health products (NHPs), most of which are purchased in pharmacies. Community pharmacists regularly field inquiries regarding NHPs. As such, pharmacists are ideally placed to answer questions about NHP use and interactions with other medications. OBJECTIVE: To identify community pharmacists' familiarity with NHPs and NHP-related adverse events (AEs) and their knowledge and ability to counsel on potential and known NHP-drug interactions. METHODS: Survey questions were derived from a literature review of previous surveys, data collected from Health Canada, and in consultation with clinicians, pharmacists, policy-makers, and researchers. A convenience sample of 321 community pharmacists in Alberta and British Columbia were asked to participate. RESULTS: We received responses from 132 pharmacists, resulting in a response rate of 41% (132/321). A total of 19% of the sample had previously reported an adverse event to Health Canada. When asked specifically about NHP-drug interactions/AEs, 47% of pharmacists stated that they had identified a potential interaction; however, only 2 of these reported it to Health Canada. Pharmacists were most familiar (76% of respondents) with the interaction between sertraline and St. John's wort and were least familiar with interactions between NHPs and anti-retrovirals. CONCLUSIONS: This survey provides evidence to suggest that pharmacists encounter reportable NHP-drug interactions, yet rarely choose to report these events. The current lack of available data on NHP AEs makes it difficult to provide patients and healthcare providers with useful strategies for managing AEs and drug interactions. Changes to the current system of monitoring AEs due to NHPs and further education of healthcare professionals regarding NHP-drug interactions is required.


Assuntos
Produtos Biológicos/efeitos adversos , Serviços Comunitários de Farmácia , Interações Ervas-Drogas , Farmacêuticos , Adulto , Produtos Biológicos/metabolismo , Serviços Comunitários de Farmácia/normas , Feminino , Interações Ervas-Drogas/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Farmacêuticos/normas
12.
Med J Aust ; 178(9): 442-3, 2003 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-12720510

RESUMO

We describe a case of acute liver failure and death associated with the use of a preparation containing the "natural" anxiolytic kava (Piper methysticum) and passionflower (Passiflora incarnata). The patient died after a report by the Therapeutic Goods Administration (TGA) warning of the potential for hepatotoxicity associated with the use of kava-containing products. The general public and alternative medicine practitioners need to be aware of the potential for non-prescription drugs to cause serious hepatic reactions.


Assuntos
Kava/efeitos adversos , Falência Hepática/induzido quimicamente , Fitoterapia/efeitos adversos , Preparações de Plantas/efeitos adversos , Terapias Complementares/métodos , Evolução Fatal , Feminino , Humanos , Pessoa de Meia-Idade , Passiflora/efeitos adversos
13.
J Nutr ; 132(6 Suppl 2): 1616S-21S, 2002 06.
Artigo em Inglês | MEDLINE | ID: mdl-12042473

RESUMO

During strenuous exercise, markers of oxidation increase and antioxidant capacity decreases. Antioxidants such as vitamin C may combat this oxidation stress. The benefits of vitamin C to greyhounds undertaking intense sprint exercise has not been investigated. The objective of this experiment was to determine whether a large dose (1 g or 57 mmol) of ascorbic acid influences performance and oxidative stress in greyhounds. Five adult female, trained racing greyhounds were assigned to receive each of three treatments for 4 wk per treatment: 1) no supplemental ascorbate; 2) 1 g oral ascorbate daily, administered after racing; 3) 1 g oral ascorbate daily, administered 1 h before racing. Dogs raced 500 m twice weekly. At the end of each treatment period, blood was collected before and 5 min, 60 min and 24 h after racing. Plasma ascorbate, alpha-tocopherol, thiobarbituric acid-reducing substances (TBARS) and Trolox equivalent antioxidant capacity (TEAC) concentrations were measured and adjusted to compensate for hemoconcentration after racing. TBARS, TEAC and alpha-tocopherol concentrations were unaffected by supplemental vitamin C. Plasma ascorbic acid concentrations 60 min after racing were higher in dogs that received vitamin C before racing than in dogs that either received no vitamin C or received vitamin C after racing. The dogs ran, on average, 0.2 s slower when supplemented with 1 g of vitamin C, equivalent to a lead of 3 m at the finish of a 500-m race. Supplementation with vitamin C, therefore, appeared to slow racing greyhounds.


Assuntos
Ácido Ascórbico/farmacologia , Cães/fisiologia , Atividade Motora/efeitos dos fármacos , Corrida , Animais , Antioxidantes/metabolismo , Ácido Ascórbico/administração & dosagem , Ácido Ascórbico/sangue , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Estresse Oxidativo/efeitos dos fármacos , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Fatores de Tempo , Vitamina E/sangue
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