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1.
Nat Cell Biol ; 22(3): 310-320, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32144411

RESUMO

Although metastasis remains the cause of most cancer-related mortality, mechanisms governing seeding in distal tissues are poorly understood. Here, we establish a robust method for the identification of global transcriptomic changes in rare metastatic cells during seeding using single-cell RNA sequencing and patient-derived-xenograft models of breast cancer. We find that both primary tumours and micrometastases display transcriptional heterogeneity but micrometastases harbour a distinct transcriptome program conserved across patient-derived-xenograft models that is highly predictive of poor survival of patients. Pathway analysis revealed mitochondrial oxidative phosphorylation as the top pathway upregulated in micrometastases, in contrast to higher levels of glycolytic enzymes in primary tumour cells, which we corroborated by flow cytometric and metabolomic analyses. Pharmacological inhibition of oxidative phosphorylation dramatically attenuated metastatic seeding in the lungs, which demonstrates the functional importance of oxidative phosphorylation in metastasis and highlights its potential as a therapeutic target to prevent metastatic spread in patients with breast cancer.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Transcriptoma , Animais , Neoplasias da Mama/metabolismo , Metabolismo Energético , Feminino , Humanos , Camundongos Endogâmicos NOD , Camundongos SCID , Mitocôndrias/metabolismo , Metástase Neoplásica , Fosforilação Oxidativa , Análise de Sequência de RNA , Análise de Célula Única , Transcrição Gênica
2.
Oxid Med Cell Longev ; 2019: 7404815, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31934268

RESUMO

Alzheimer's disease (AD) is the most prevalent form of dementia and is associated with loss of memory, amyloid-beta plaque buildup, and neurofibrillary tangles. These features might be a result of neuronal cell death in the cerebral cortex and hippocampal regions of the brain. AD pathologies can be attributed to a variety of biochemical consequences including mitochondrial dysfunction, increased oxidative stress, and autophagy inhibition. Unfortunately, current therapeutics are limited only to symptomatic relief and do not halt the progression of neurodegeneration. Previous in vitro experiments have shown that a water-soluble formulation of coenzyme-Q10, Ubisol-Q10, can stabilize the mitochondria, prevent oxidative stress, and inhibit premature senescence in fibroblasts of AD patients. Since autophagy plays a critical role in maintenance and survival of neurons, we hypothesized that Ubisol-Q10 treatment could result in resumption of autophagy. Indeed, we observed induction of autophagy by Ubisol-Q10 treatment in AD fibroblasts as well as in the brains of transgenic AD mice. We found increased expression of autophagy-related genes beclin-1 and JNK1 following Ubisol-Q10 treatment of AD fibroblasts. These results were confirmed at the protein level by immunofluorescence and Western blotting. Interestingly, despite reduction of oxidative stress in cells due to Ubisol-Q10 treatment, autophagy inhibition leads to resumption of premature senescence in these PS-1 mutated fibroblasts indicating that autophagy is critical to prevent the senescence phenotype. Withdrawal of Ubisol-Q10 treatment also leads to the return of the senescence phenotype in AD fibroblasts indicating that constant supplementation of Ubisol-Q10 is required. Additionally, Ubisol-Q10 supplementation in the drinking water of double transgenic AD mice leads to increased expression of beclin-1 and JNK1 in the cortical region. Thus, the activation of autophagy by Ubisol-Q10 could be the mechanism for its ability to halt the progression of AD pathology in transgenic AD mice shown previously.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Córtex Cerebral/metabolismo , Fibroblastos/fisiologia , Mutação/genética , Presenilina-1/genética , Ubiquinona/análogos & derivados , Animais , Autofagia , Proteína Beclina-1/genética , Proteína Beclina-1/metabolismo , Morte Celular , Senescência Celular/efeitos dos fármacos , Córtex Cerebral/efeitos dos fármacos , Modelos Animais de Doenças , Fibroblastos/efeitos dos fármacos , Humanos , Camundongos , Camundongos Transgênicos , Proteína Quinase 8 Ativada por Mitógeno/genética , Proteína Quinase 8 Ativada por Mitógeno/metabolismo , Neuroproteção , Ubiquinona/química , Ubiquinona/uso terapêutico , Regulação para Cima
3.
BMC Health Serv Res ; 18(1): 970, 2018 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-30558605

RESUMO

BACKGROUND: Chronic back disorders (CBD) are prevalent, costly, and among the most common reasons for seeking primary care; however, little is known regarding the comparative use of family physician, chiropractic, and physiotherapy services among people with CBD in Canada. Elucidating these differences may identify potential gaps in access to care and inform the development of strategies to improve access. The research objectives were to investigate patterns of health care use and to profile factors associated with self-reported use of family physicians, chiropractors, and physiotherapists among adult Canadians with CBD. METHODS: The combined 2009 and 2010 Canadian Community Health Surveys conducted by Statistics Canada were used to investigate self-reported health care use among adults with CBD. This complex survey employs population weights and bootstrapping to be representative of the Canadian population. Following descriptive analyses, we used multiple logistic regression to profile self-reported health care use while statistically controlling for possible confounding effects. RESULTS: The majority of adult respondents with CBD sought care only with a family physician (53.8%), with 20.9% and 16.2% seeking care with combined family physician/chiropractor or family physician/physiotherapist, respectively. Few respondents sought care only with a chiropractor (2.5%) or physiotherapist (1.0%). After adjustment, differential patterns of utilization (p < 0.05) were evident between provider groups with respect to age, gender, socioeconomic status, rural/urban residence, functional limitations, and presence of co-morbidities. CONCLUSIONS: This research highlights potential inequities in access to physiotherapists and chiropractors in relation to family physicians among adult Canadians with CBD, particularly among lower socioeconomic status and rural/remote populations.


Assuntos
Dor nas Costas/terapia , Quiroprática/estatística & dados numéricos , Medicina de Família e Comunidade/estatística & dados numéricos , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Modalidades de Fisioterapia/estatística & dados numéricos , Adolescente , Adulto , Distribuição por Idade , Idoso , Dor nas Costas/epidemiologia , Canadá/epidemiologia , Dor Crônica/epidemiologia , Serviços de Saúde Comunitária/estatística & dados numéricos , Comorbidade , Utilização de Instalações e Serviços , Feminino , Inquéritos Epidemiológicos , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Fisioterapeutas/estatística & dados numéricos , Médicos de Família/estatística & dados numéricos , Prevalência , Saúde da População Rural/estatística & dados numéricos , Autorrelato , Inquéritos e Questionários , Adulto Jovem
4.
BMC Oral Health ; 16: 3, 2016 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-26762247

RESUMO

BACKGROUND: Numerous strategies have been proposed to decrease orthodontic treatment time. Photobiomodulation (PBM) has previously been demonstrated to assist in this objective. The aim of this study was to test if intraoral PBM increases the rate of tooth alignment and reduces the time required to resolve anterior dental crowding. METHODS: Nineteen orthodontic subjects with Class I or Class II malocclusion and Little's Irregularity Index (LII) ≥ 3 mm were selected from a pool of applicants, providing 28 total arches. No cases required extraction. The test group (N = 11, 18 arches, 10 upper, 8 lower) received daily PBM treatment with an intraoral LED device (OrthoPulse™, Biolux Research Ltd.) during orthodontic treatment, while the control group (N = 8, 10 arches, 3 upper, 7 lower) received only orthodontic treatment. The PBM device exposed the buccal side of the gums to near-infrared light with a continuous 850-nm wavelength, generating an average daily energy density of 9.5 J/cm(2). LII was measured at the start (T0) of orthodontic treatment until alignment was reached (T1, where LII ≤ 1 mm). The control group was mostly bonded with 0.018-in slot self-ligating SPEED brackets (Hespeler Orthodontics, Cambridge, ON. Canada), while conventionally-ligating Ormco Mini-Diamond twins were used on the PBM group (Ormco, Glendora, Calif. USA). Both groups progressed through alignment with NiTi arch-wires from 0.014-in through to 0.018-in (Ormco), with identical arch-wire changes. The rate of anterior alignment, in LII mm/week, and total treatment time was collected for both groups. Cox proportional hazards models were used to compare groups and while considering age, sex, ethnicity, arch and degree of crowding. RESULTS: The mean alignment rate for the PBM group was significantly higher than that of the control group, with an LII change rate of 1.27 mm/week (SD 0.53, 95 % CI ± 0.26) versus 0.44 mm/week (SD 0.20, 95 % CI ± 0.12), respectively (p = 0.0002). The treatment time to alignment was significantly smaller for the PBM group, which achieved alignment in 48 days (SD 39, 95 % CI ± 39), while the control group took 104 days (SD 55, 95 % CI ±19, p = 0.0053) on average. These results demonstrated that intraoral PBM increased the average rate of tooth movement by 2.9-fold, resulting in a 54 % average decrease in alignment duration versus control. The average PBM compliance to daily treatments was 93 % during alignment. CONCLUSIONS: Under the limitations of this study, the findings suggest that intraoral PBM could be used to decrease anterior alignment treatment time, which could consequently decrease full orthodontic treatment time. However, due to its limitations, further research in the form of a large, randomized trial is needed. TRIAL REGISTRATION: ClinicalTrials.gov NCT02267837 . Registered 10 October 2014.


Assuntos
Má Oclusão/terapia , Fototerapia/métodos , Técnicas de Movimentação Dentária/métodos , Humanos , Braquetes Ortodônticos , Fios Ortodônticos , Doses de Radiação , Fatores de Tempo
5.
PLoS One ; 9(11): e113250, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25401766

RESUMO

BACKGROUND: Currently chemotherapy is limited mostly to genotoxic drugs that are associated with severe side effects due to non-selective targeting of normal tissue. Natural products play a significant role in the development of most chemotherapeutic agents, with 74.8% of all available chemotherapy being derived from natural products. OBJECTIVE: To scientifically assess and validate the anticancer potential of an ethanolic extract of the fruit of the Long pepper (PLX), a plant of the piperaceae family that has been used in traditional medicine, especially Ayurveda and investigate the anticancer mechanism of action of PLX against cancer cells. MATERIALS & METHODS: Following treatment with ethanolic long pepper extract, cell viability was assessed using a water-soluble tetrazolium salt; apoptosis induction was observed following nuclear staining by Hoechst, binding of annexin V to the externalized phosphatidyl serine and phase contrast microscopy. Image-based cytometry was used to detect the effect of long pepper extract on the production of reactive oxygen species and the dissipation of the mitochondrial membrane potential following Tetramethylrhodamine or 5,5,6,6'-tetrachloro-1,1',3,3'-tetraethylbenzimidazolylcarbocyanine chloride staining (JC-1). Assessment of PLX in-vivo was carried out using Balb/C mice (toxicity) and CD-1 nu/nu immunocompromised mice (efficacy). HPLC analysis enabled detection of some primary compounds present within our long pepper extract. RESULTS: Our results indicated that an ethanolic long pepper extract selectively induces caspase-independent apoptosis in cancer cells, without affecting non-cancerous cells, by targeting the mitochondria, leading to dissipation of the mitochondrial membrane potential and increase in ROS production. Release of the AIF and endonuclease G from isolated mitochondria confirms the mitochondria as a potential target of long pepper. The efficacy of PLX in in-vivo studies indicates that oral administration is able to halt the growth of colon cancer tumors in immunocompromised mice, with no associated toxicity. These results demonstrate the potentially safe and non-toxic alternative that is long pepper extract for cancer therapy.


Assuntos
Apoptose/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Piper/química , Extratos Vegetais/farmacologia , Animais , Western Blotting , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Humanos , Técnicas Imunoenzimáticas , Técnicas In Vitro , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Neoplasias/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
6.
Prog Orthod ; 14: 30, 2013 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-24326198

RESUMO

BACKGROUND: Numerous strategies have been proposed to decrease the treatment time a patient requires in orthodontic treatment. Recently, a number of device-accelerated therapies have emerged in orthodontics. Photobiomodulation is an emerging area of science that has clinical applications in a number of human biological processes. The aim of this study was to determine if photobiomodulation reduces the treatment time in the alignment phase of orthodontic treatment. METHODS: This multicenter clinical trial was performed on 90 subjects (73 test subjects and 17 controls), and Little's Index of Irregularity (LII) was used as a measure of the rate of change of tooth movement. Subjects requiring orthodontic treatment were recruited into the study, and the LII was measured at regular time intervals. Test subjects used a device which produced near-infrared light with a continuous 850-nm wavelength. The surface of the cheek was irradiated with a power density of 60 mW/cm2 for 20 or 30 min/day or 60 min/week to achieve total energy densities of 72, 108, or 216 J/cm2, respectively. All subjects were fitted with traditional orthodontic brackets and wires. The wire sequences for each site were standardized to an initial round alignment wire (014 NiTi or 016 NiTi) and then advanced through a progression of stiffer arch wires unit alignment occurred (LII<1 mm). RESULTS: The mean LII scores at the start of the clinical trial for the test and control groups were 6.35 and 5.04 mm, respectively. Multi-level mixed effect regression analysis was performed on the data, and the mean rate of change in LII was 0.49 and 1.12 mm/week for the control and test groups, respectively. CONCLUSIONS: Photobiomodulation produced clinically significant changes in the rates of tooth movement as compared to the control group during the alignment phase of orthodontic treatment.


Assuntos
Fototerapia/métodos , Técnicas de Movimentação Dentária/métodos , Adolescente , Adulto , Estudos de Casos e Controles , Criança , Estudos de Coortes , Feminino , Humanos , Raios Infravermelhos/uso terapêutico , Masculino , Má Oclusão Classe I de Angle/terapia , Braquetes Ortodônticos , Fios Ortodônticos , Doses de Radiação , Fatores de Tempo , Técnicas de Movimentação Dentária/instrumentação , Resultado do Tratamento , Adulto Jovem
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