Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 204
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Stroke ; 54(9): 2254-2264, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37577801

RESUMO

BACKGROUND: To determine if low-frequency repetitive transcranial magnetic stimulation targeting the primary motor cortex contralateral (M1CL) to the affected corticospinal tract in patients with hemiparetic stroke augments intensive training-related clinical improvement; an extension of the NICHE trial (Navigated Inhibitory rTMS to Contralesional Hemisphere Trial) using an alternative sham coil. METHODS: The present E-FIT trial (Electric Field Navigated 1Hz rTMS for Post-stroke Motor Recovery Trial) included 5 of 12 NICHE trial outpatient US rehabilitation centers. The stimulation protocol remained identical (1 Hz repetitive transcranial magnetic stimulation, M1CL, preceding 60-minute therapy, 18 sessions/6 wks; parallel arm randomized clinical trial). The sham coil appearance mimicked the active coil but without the weak electric field in the NICHE trial sham coil. Outcomes measured 1 week, and 1, 3, and 6 months after the end of treatment included the following: upper extremity Fugl-Meyer (primary, 6 months after end of treatment), Action Research Arm Test, National Institutes of Health Stroke Scale, quality of life (EQ-5D), and safety. RESULTS: Of 60 participants randomized, 58 completed treatment and were included for analysis. Bayesian analysis of combined data from the E-FIT and the NICHE trials indicated that active treatment was not superior to sham at the primary end point (posterior mean odds ratio of 1.94 [96% credible interval of 0.61-4.80]). For the E-FIT intent-to-treat population, upper extremity Fugl-Meyer improvement ≥5 pts occurred in 60% (18/30) active group and 50% (14/28) sham group. Participants enrolled 3 to 6 months following stroke had a 67% (31%-91% CI) response rate in the active group at the 6-month end point versus 50% in the sham group (21.5%-78.5% CI). There were significant improvements from baseline to 6 months for both active and sham groups in upper extremity Fugl-Meyer, Action Research Arm Test, and EQ-5D (P<0.05). Improvement in National Institutes of Health Stroke Scale was observed only in the active group (P=0.004). Ten serious unrelated adverse events occurred (4 active group, 6 sham group, P=0.72). CONCLUSIONS: Intensive motor rehabilitation 3 to 12 months after stroke improved clinical impairment, function, and quality of life; however, 1 Hz-repetitive transcranial magnetic stimulation was not an effective treatment adjuvant in the present sample population with mixed lesion location and extent. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT03010462.


Assuntos
Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Humanos , Reabilitação do Acidente Vascular Cerebral/métodos , Qualidade de Vida , Teorema de Bayes , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/terapia , Estimulação Magnética Transcraniana/métodos , Resultado do Tratamento , Extremidade Superior , Recuperação de Função Fisiológica
2.
Eur J Neurosci ; 57(4): 619-632, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36512398

RESUMO

Cross-education is the phenomenon where training of one limb can cause neuromuscular adaptations in the opposite untrained limb. This effect has been reported to be greater after eccentric (ECC) than concentric (CON) strength training; however, the underpinning neurophysiological mechanisms remain unclear. Thus, we compared responses to transcranial magnetic stimulation (TMS) in both motor cortices following single sessions of unilateral ECC and CON exercise of the elbow flexors. Fourteen healthy adults performed three sets of 10 ECC and CON right elbow flexor contractions at 75% of respective maximum on separate days. Elbow flexor maximal voluntary isometric contraction (MVIC) torques were measured before and after exercise, and responses to single- and paired-pulse TMS were recorded from the non-exercised left and exercised right biceps brachii. Pre-exercise and post-exercise responses for ECC and CON were compared by repeated measures analyses of variance (ANOVAs). MVIC torque of the exercised arm decreased (p < 0.01) after CON (-30 ± 14%) and ECC (-39 ± 13%) similarly. For the non-exercised left biceps brachii, resting motor threshold (RMT) decreased after CON only (-4.2 ± 3.9% of maximum stimulator output [MSO], p < 0.01), and intracortical facilitation (ICF) decreased (-15.2 ± 20.0%, p = 0.038) after ECC only. For the exercised right biceps, RMT increased after ECC (8.6 ± 6.2% MSO, p = 0.014) but not after CON (6.4 ± 8.1% MSO, p = 0.066). Thus, unilateral ECC and CON elbow flexor exercise modulated excitability differently for the non-exercised hemisphere. These findings suggest that responses after a single bout of exercise may not reflect longer term adaptations.


Assuntos
Braço , Músculo Esquelético , Adulto , Humanos , Músculo Esquelético/fisiologia , Cotovelo , Contração Isométrica , Terapia por Exercício , Contração Muscular/fisiologia
3.
Brain ; 145(4): 1338-1353, 2022 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-35025994

RESUMO

Clinicians and scientists alike have long sought to predict the course and severity of chronic post-stroke cognitive and motor outcomes, as the ability to do so would inform treatment and rehabilitation strategies. However, it remains difficult to make accurate predictions about chronic post-stroke outcomes due, in large part, to high inter-individual variability in recovery and a reliance on clinical heuristics rather than empirical methods. The neuroanatomical location of a stroke is a key variable associated with long-term outcomes, and because lesion location can be derived from routinely collected clinical neuroimaging data there is an opportunity to use this information to make empirically based predictions about post-stroke deficits. For example, lesion location can be compared to statistically weighted multivariate lesion-behaviour maps of neuroanatomical regions that, when damaged, are associated with specific deficits based on aggregated outcome data from large cohorts. Here, our goal was to evaluate whether we can leverage lesion-behaviour maps based on data from two large cohorts of individuals with focal brain lesions to make predictions of 12-month cognitive and motor outcomes in an independent sample of stroke patients. Further, we evaluated whether we could augment these predictions by estimating the structural and functional networks disrupted in association with each lesion-behaviour map through the use of structural and functional lesion network mapping, which use normative structural and functional connectivity data from neurologically healthy individuals to elucidate lesion-associated networks. We derived these brain network maps using the anatomical regions with the strongest association with impairment for each cognitive and motor outcome based on lesion-behaviour map results. These peak regional findings became the 'seeds' to generate networks, an approach that offers potentially greater precision compared to previously used single-lesion approaches. Next, in an independent sample, we quantified the overlap of each lesion location with the lesion-behaviour maps and structural and functional lesion network mapping and evaluated how much variance each could explain in 12-month behavioural outcomes using a latent growth curve statistical model. We found that each lesion-deficit mapping modality was able to predict a statistically significant amount of variance in cognitive and motor outcomes. Both structural and functional lesion network maps were able to predict variance in 12-month outcomes beyond lesion-behaviour mapping. Functional lesion network mapping performed best for the prediction of language deficits, and structural lesion network mapping performed best for the prediction of motor deficits. Altogether, these results support the notion that lesion location and lesion network mapping can be combined to improve the prediction of post-stroke deficits at 12-months.


Assuntos
Encéfalo , Acidente Vascular Cerebral , Encéfalo/patologia , Mapeamento Encefálico/métodos , Humanos , Idioma , Imageamento por Ressonância Magnética/métodos , Neuroimagem , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/patologia
4.
Int J Mol Sci ; 24(13)2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37445934

RESUMO

The process of human embryonic mammary development gives rise to the structures in which mammary cells share a developmental lineage with skin epithelial cells such as keratinocytes. As some breast carcinomas have previously been shown to express high levels of involucrin, a marker of keratinocyte differentiation, we hypothesised that some breast tumours may de-differentiate to a keratinocyte-derived 'evolutionary history'. To confirm our hypothesis, we investigated the frequency of involucrin expression along with that of Brk, a tyrosine kinase expressed in up to 86% of breast carcinomas whose normal expression patterns are restricted to differentiating epithelial cells, most notably those in the skin (keratinocytes) and the gastrointestinal tract. We found that involucrin, a keratinocyte differentiation marker, was expressed in a high proportion (78%) of breast carcinoma samples and cell lines. Interestingly, tumour samples found to express high levels of involucrin were also shown to express Brk. 1,25-dihydroxyvitamin D3, a known differentiation agent and potential anti-cancer agent, decreased proliferation in the breast cancer cell lines that expressed both involucrin and Brk, whereas the Brk/involucrin negative cell lines tested were less susceptible. In addition, responses to 1,25-dihydroxyvitamin D3 were not correlated with vitamin D receptor expression. These data contribute to the growing body of evidence suggesting that cellular responses to 1,25-dihydroxyvitamin D3 are potentially independent of vitamin D receptor status and provide an insight into potential markers, such as Brk and/or involucrin that could predict therapeutic responses to 1,25-dihydroxyvitamin D3.


Assuntos
Neoplasias da Mama , Receptores de Calcitriol , Humanos , Feminino , Neoplasias da Mama/metabolismo , Colecalciferol , Calcitriol , Proteínas de Neoplasias/metabolismo , Proteínas Tirosina Quinases
5.
J Cell Sci ; 133(7)2020 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-32269093

RESUMO

ADAMTS-1 is an extracellular protease with critical roles in organogenesis and angiogenesis. Here we demonstrate a functional convergence of ADAMTS-1 and the transmembrane heparan sulfate proteoglycan syndecan-4 in influencing adhesion, migration and angiogenesis. Knockdown of ADAMTS-1 in endothelial cells resulted in a parallel reduction in cell surface syndecan-4, attributable to increased matrix metalloproteinase-9 (MMP9) activity. Knockdown of either ADAMTS-1 or syndecan-4 increased cellular responses to vascular endothelial growth factor A isoform VEGFA164, and increased ex vivo aortic ring microvessel sprouting. On fibronectin, knockdown of either protein enhanced migration and promoted formation of long α5 integrin-containing fibrillar adhesions. However, integrin α5 null cells still showed increased migration in response to ADAMTS-1 and syndecan-4 siRNA treatment. Plating of naïve endothelial cells on cell-conditioned matrix from ADAMTS-1 and syndecan-4 knockdown cells demonstrated that the altered adhesive behaviour was matrix dependent, and this correlated with a lack of expression of fibulin-1: an extracellular matrix co-factor for ADAMTS-1 that is known to inhibit migration. These findings support the notion that ADAMTS-1 and syndecan-4 are functionally interconnected in regulating cell migration and angiogenesis, via collaboration with MMP9 and fibulin-1.This article has an associated First Person interview with the first author of the paper.


Assuntos
Sindecana-4 , Fator A de Crescimento do Endotélio Vascular , Proteína ADAMTS1 , Animais , Adesão Celular , Movimento Celular , Células Endoteliais , Humanos , Camundongos , Neovascularização Patológica , Sindecana-1 , Sindecana-2 , Sindecana-4/genética
6.
Spinal Cord ; 60(6): 522-532, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35094007

RESUMO

STUDY DESIGN: Clinical trial. OBJECTIVE: To demonstrate that a 12-week exoskeleton-based robotic gait training regimen can lead to a clinically meaningful improvement in independent gait speed, in community-dwelling participants with chronic incomplete spinal cord injury (iSCI). SETTING: Outpatient rehabilitation or research institute. METHODS: Multi-site (United States), randomized, controlled trial, comparing exoskeleton gait training (12 weeks, 36 sessions) with standard gait training or no gait training (2:2:1 randomization) in chronic iSCI (>1 year post injury, AIS-C, and D), with residual stepping ability. The primary outcome measure was change in robot-independent gait speed (10-meter walk test, 10MWT) post 12-week intervention. Secondary outcomes included: Timed-Up-and-Go (TUG), 6-min walk test (6MWT), Walking Index for Spinal Cord Injury (WISCI-II) (assistance and devices), and treating therapist NASA-Task Load Index. RESULTS: Twenty-five participants completed the assessments and training as assigned (9 Ekso, 10 Active Control, 6 Passive Control). Mean change in gait speed at the primary endpoint was not statistically significant. The proportion of participants with improvement in clinical ambulation category from home to community speed post-intervention was greatest in the Ekso group (>1/2 Ekso, 1/3 Active Control, 0 Passive Control, p < 0.05). Improvements in secondary outcome measures were not significant. CONCLUSIONS: Twelve weeks of exoskeleton robotic training in chronic SCI participants with independent stepping ability at baseline can improve clinical ambulatory status. Improvements in raw gait speed were not statistically significant at the group level, which may guide future trials for participant inclusion criteria. While generally safe and tolerable, larger gains in ambulation might be associated with higher risk for non-serious adverse events.


Assuntos
Exoesqueleto Energizado , Procedimentos Cirúrgicos Robóticos , Robótica , Traumatismos da Medula Espinal , Terapia por Exercício , Marcha , Humanos , Traumatismos da Medula Espinal/complicações , Caminhada
7.
Br J Cancer ; 122(10): 1467-1476, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32203215

RESUMO

BACKGROUND: Unsupervised learning methods, such as Hierarchical Cluster Analysis, are commonly used for the analysis of genomic platform data. Unfortunately, such approaches ignore the well-documented heterogeneous composition of prostate cancer samples. Our aim is to use more sophisticated analytical approaches to deconvolute the structure of prostate cancer transcriptome data, providing novel clinically actionable information for this disease. METHODS: We apply an unsupervised model called Latent Process Decomposition (LPD), which can handle heterogeneity within individual cancer samples, to genome-wide expression data from eight prostate cancer clinical series, including 1,785 malignant samples with the clinical endpoints of PSA failure and metastasis. RESULTS: We show that PSA failure is correlated with the level of an expression signature called DESNT (HR = 1.52, 95% CI = [1.36, 1.7], P = 9.0 × 10-14, Cox model), and that patients with a majority DESNT signature have an increased metastatic risk (X2 test, P = 0.0017, and P = 0.0019). In addition, we develop a stratification framework that incorporates DESNT and identifies three novel molecular subtypes of prostate cancer. CONCLUSIONS: These results highlight the importance of using more complex approaches for the analysis of genomic data, may assist drug targeting, and have allowed the construction of a nomogram combining DESNT with other clinical factors for use in clinical management.


Assuntos
Biomarcadores Tumorais/sangue , Perfilação da Expressão Gênica/estatística & dados numéricos , Neoplasias da Próstata/genética , Transcriptoma/genética , Regulação Neoplásica da Expressão Gênica/genética , Genômica/estatística & dados numéricos , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Prognóstico , Intervalo Livre de Progressão , Modelos de Riscos Proporcionais , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/sangue , Neoplasias da Próstata/patologia , Medição de Risco , Fatores de Risco
8.
EMBO Rep ; 19(7)2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29794156

RESUMO

Integrin ß3 is seen as a key anti-angiogenic target for cancer treatment due to its expression on neovasculature, but the role it plays in the process is complex; whether it is pro- or anti-angiogenic depends on the context in which it is expressed. To understand precisely ß3's role in regulating integrin adhesion complexes in endothelial cells, we characterised, by mass spectrometry, the ß3-dependent adhesome. We show that depletion of ß3-integrin in this cell type leads to changes in microtubule behaviour that control cell migration. ß3-integrin regulates microtubule stability in endothelial cells through Rcc2/Anxa2-driven control of active Rac1 localisation. Our findings reveal that angiogenic processes, both in vitro and in vivo, are more sensitive to microtubule targeting agents when ß3-integrin levels are reduced.


Assuntos
Adesão Celular/genética , Movimento Celular/genética , Integrina beta3/genética , Animais , Anexina A2/genética , Proteínas Cromossômicas não Histona/genética , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Endotélio Vascular , Regulação da Expressão Gênica/genética , Humanos , Espectrometria de Massas , Camundongos , Microtúbulos/genética , Microtúbulos/patologia , Neoplasias/genética , Neoplasias/patologia , Neovascularização Patológica/genética , Neovascularização Patológica/patologia , Proteínas rac1 de Ligação ao GTP/genética
9.
Blood ; 130(14): 1649-1660, 2017 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-28733324

RESUMO

Improvements in the understanding of the metabolic cross-talk between cancer and its microenvironment are expected to lead to novel therapeutic approaches. Acute myeloid leukemia (AML) cells have increased mitochondria compared with nonmalignant CD34+ hematopoietic progenitor cells. Furthermore, contrary to the Warburg hypothesis, AML relies on oxidative phosphorylation to generate adenosine triphosphate. Here we report that in human AML, NOX2 generates superoxide, which stimulates bone marrow stromal cells (BMSC) to AML blast transfer of mitochondria through AML-derived tunneling nanotubes. Moreover, inhibition of NOX2 was able to prevent mitochondrial transfer, increase AML apoptosis, and improve NSG AML mouse survival. Although mitochondrial transfer from BMSC to nonmalignant CD34+ cells occurs in response to oxidative stress, NOX2 inhibition had no detectable effect on nonmalignant CD34+ cell survival. Taken together, we identify tumor-specific dependence on NOX2-driven mitochondrial transfer as a novel therapeutic strategy in AML.


Assuntos
Leucemia Mieloide Aguda/patologia , Glicoproteínas de Membrana/metabolismo , Células-Tronco Mesenquimais/patologia , Mitocôndrias/patologia , NADPH Oxidases/metabolismo , Superóxidos/metabolismo , Animais , Antígenos CD34/metabolismo , Células-Tronco Hematopoéticas/metabolismo , Células-Tronco Hematopoéticas/patologia , Humanos , Leucemia Mieloide Aguda/metabolismo , Células-Tronco Mesenquimais/metabolismo , Camundongos , Mitocôndrias/metabolismo , NADPH Oxidase 2 , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Células Tumorais Cultivadas
10.
Blood ; 129(10): 1320-1332, 2017 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-28049638

RESUMO

Despite currently available therapies, most patients diagnosed with acute myeloid leukemia (AML) die of their disease. Tumor-host interactions are critical for the survival and proliferation of cancer cells; accordingly, we hypothesize that specific targeting of the tumor microenvironment may constitute an alternative or additional strategy to conventional tumor-directed chemotherapy. Because adipocytes have been shown to promote breast and prostate cancer proliferation, and because the bone marrow adipose tissue accounts for up to 70% of bone marrow volume in adult humans, we examined the adipocyte-leukemia cell interactions to determine if they are essential for the growth and survival of AML. Using in vivo and in vitro models of AML, we show that bone marrow adipocytes from the tumor microenvironment support the survival and proliferation of malignant cells from patients with AML. We show that AML blasts alter metabolic processes in adipocytes to induce phosphorylation of hormone-sensitive lipase and consequently activate lipolysis, which then enables the transfer of fatty acids from adipocytes to AML blasts. In addition, we report that fatty acid binding protein-4 (FABP4) messenger RNA is upregulated in adipocytes and AML when in coculture. FABP4 inhibition using FABP4 short hairpin RNA knockdown or a small molecule inhibitor prevents AML proliferation on adipocytes. Moreover, knockdown of FABP4 increases survival in Hoxa9/Meis1-driven AML model. Finally, knockdown of carnitine palmitoyltransferase IA in an AML patient-derived xenograft model improves survival. Here, we report the first description of AML programming bone marrow adipocytes to generate a protumoral microenvironment.


Assuntos
Adipócitos/patologia , Células da Medula Óssea/patologia , Leucemia Mieloide Aguda/patologia , Microambiente Tumoral/fisiologia , Adipócitos/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Western Blotting , Células da Medula Óssea/metabolismo , Técnicas de Cocultura , Proteínas de Ligação a Ácido Graxo/metabolismo , Feminino , Citometria de Fluxo , Xenoenxertos , Humanos , Imuno-Histoquímica , Leucemia Mieloide Aguda/metabolismo , Masculino , Camundongos , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase Via Transcriptase Reversa
11.
Stroke ; 49(9): 2138-2146, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30354990

RESUMO

Background and Purpose- We aimed to determine whether low-frequency electric field navigated repetitive transcranial magnetic stimulation to noninjured motor cortex versus sham repetitive transcranial magnetic stimulation avoiding motor cortex could improve arm motor function in hemiplegic stroke patients when combined with motor training. Methods- Twelve outpatient US rehabilitation centers enrolled participants between May 2014 and December 2015. We delivered 1 Hz active or sham repetitive transcranial magnetic stimulation to noninjured motor cortex before each of eighteen 60-minute therapy sessions over a 6-week period, with outcomes measured at 1 week and 1, 3, and 6 months after end of treatment. The primary end point was the percentage of participants improving ≥5 points on upper extremity Fugl-Meyer score 6 months after end of treatment. Secondary analyses assessed changes on the upper extremity Fugl-Meyer and Action Research Arm Test and Wolf Motor Function Test and safety. Results- Of 199 participants, 167 completed treatment and follow-up because of early discontinuation of data collection. Upper extremity Fugl-Meyer gains were significant for experimental ( P<0.001) and sham groups ( P<0.001). Sixty-seven percent of the experimental group (95% CI, 58%-75%) and 65% of sham group (95% CI, 52%-76%) improved ≥5 points on 6-month upper extremity Fugl-Meyer ( P=0.76). There was also no difference between experimental and sham groups in the Action Research Arm Test ( P=0.80) or the Wolf Motor Function Test ( P=0.55). A total of 26 serious adverse events occurred in 18 participants, with none related to the study or device, and with no difference between groups. Conclusions- Among patients 3 to 12 months poststroke, goal-oriented motor rehabilitation improved motor function 6 months after end of treatment. There was no difference between the active and sham repetitive transcranial magnetic stimulation trial arms. Clinical Trial Registration- URL: https://www.clinicaltrials.gov . Unique identifier: NCT02089464.


Assuntos
Córtex Motor , Reabilitação do Acidente Vascular Cerebral/métodos , Acidente Vascular Cerebral/terapia , Estimulação Magnética Transcraniana/métodos , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Acidente Vascular Cerebral/fisiopatologia , Resultado do Tratamento , Extremidade Superior/fisiopatologia
12.
J Stroke Cerebrovasc Dis ; 27(12): 3621-3625, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30314762

RESUMO

OBJECTIVE: To compare the effects of Transcranial Direct Current Stimulation (tDCS) versus Galvanic Vestibular Stimulation (GVS) on Lateropulsion following stroke. METHODS: Patients with Stroke and Burke Lateropulsion Scale (BLS) scores greater than or equal to 2 gave informed consent to receive sinusoidal 1 Hz DC (0-2 mA) anodal stimulation over the affected parietal cortex versus similar GVS with ipsilesional mastoidal anode. Seated haptic center of pressure (COP-X) was measured using an AMTI analog-to-digital forceplate. An inclinometer (Biopac ) measured lateral thoracic tilt. COP-X Power Spectra were analyzed over 3 frequency intervals: 0-.3 Hz, .3-1 Hz, and 1-3 Hz. RESULTS: Six males/4 females age 66 ± 9.5 standard deviation with admission BLS scores of 5.4 ± 3.7 within 8.6 ± 8.1 days poststroke were enrolled. COP-X medial-lateral speed increased for both the tDCS and the GVS protocols compared to sham condition. Fourier Analysis of COP-X velocity for 0-.3 Hz responses showed a significant increase for tDCS stimulation. The .3-1 Hz responses for the tDCS condition were decreased from baseline. Lateral thoracic tilt showed significant improvement for tDCS compared to Sham stimulation at 10 minutes and for GVS versus Sham at 15 minutes. DISCUSSION: Anodal tDCS over the ipsilesional PIVC increases low frequency postural responses usually attributed to visual control with down regulation of median frequency vestibular responses, biasing postural control toward more dependence on visual as opposed to vestibular control. CONCLUSIONS: 2 mA sinusoidal 1 Hz anodal tDCS over the ipsi-lesional PIVC or similar ipsi-lesional anodal GVS improve Lateropulsion following stroke.


Assuntos
Terapia por Estimulação Elétrica/métodos , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral/complicações , Doenças Vestibulares/etiologia , Doenças Vestibulares/terapia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Lobo Parietal , Projetos Piloto , Postura , Acidente Vascular Cerebral/fisiopatologia , Resultado do Tratamento , Núcleos Vestibulares
13.
Breast Cancer Res ; 19(1): 33, 2017 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-28330493

RESUMO

BACKGROUND: Normal myoepithelial cells (MECs) play an important tumour-suppressor role in the breast but display an altered phenotype in ductal carcinoma in situ (DCIS), gaining tumour-promoter functions. Matrix metalloproteinase-8 (MMP-8) is expressed by normal MECs but is lost in DCIS. This study investigated the function of MMP-8 in MECs and the impact of its loss in DCIS. METHODS: Primary normal and DCIS-associated MECs, and normal (N-1089) and DCIS-modified myoepithelial (ß6-1089) cell lines, were used to assess MMP-8 expression and function. ß6-1089 lacking MMP-8 were transfected with MMP-8 WT and catalytically inactive MMP-8 EA, and MMP-8 in N-1089 MEC was knocked down with siRNA. The effect on adhesion and migration to extracellular matrix (ECM), localisation of α6ß4 integrin to hemidesmosomes (HD), TGF-ß signalling and gelatinase activity was measured. The effect of altering MEC MMP-8 expression on tumour cell invasion was investigated in 2D and 3D organotypic models. RESULTS: Assessment of primary cells and MEC lines confirmed expression of MMP-8 in normal MEC and its loss in DCIS-MEC. Over-expression of MMP-8 WT but not MMP-8 EA in ß6-1089 cells increased adhesion to ECM proteins and reduced migration. Conversely, knock-down of MMP-8 in N-1089 reduced adhesion and increased migration. Expression of MMP-8 WT in ß6-1089 led to greater localisation of α6ß4 to HD and reduced retraction fibre formation, this being reversed by MMP-8 knock-down in N-1089. Over-expression of MMP-8 WT reduced TGF-ß signalling and gelatinolytic activity. MMP-8 knock-down enhanced TGF-ß signalling and gelatinolytic activity, which was reversed by blocking MMP-9 by knock-down or an inhibitor. MMP-8 WT but not MMP-8 EA over-expression in ß6-1089 reduced breast cancer cell invasion in 2D and 3D invasion assays, while MMP-8 knock-down in N-1089 enhanced cancer cell invasion. Staining of breast cancer cases for MMP-8 revealed a statistically significant loss of MMP-8 expression in DCIS with invasion versus pure DCIS (p = 0.001). CONCLUSIONS: These data indicate MMP-8 is a vital component of the myoepithelial tumour-suppressor function. It restores MEC interaction with the matrix, opposes TGF-ß signalling and MMP-9 proteolysis, which contributes to inhibition of tumour cell invasion. Assessment of MMP-8 expression may help to determine risk of DCIS progression.


Assuntos
Carcinoma Ductal de Mama/genética , Carcinoma Ductal de Mama/metabolismo , Carcinoma Intraductal não Infiltrante/genética , Carcinoma Intraductal não Infiltrante/metabolismo , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Células Epiteliais/metabolismo , Metaloproteinase 8 da Matriz/deficiência , Biomarcadores Tumorais , Carcinoma Ductal de Mama/patologia , Carcinoma Intraductal não Infiltrante/patologia , Adesão Celular , Linhagem Celular Transformada , Linhagem Celular Tumoral , Movimento Celular , Sobrevivência Celular , Feminino , Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Imuno-Histoquímica , Integrina alfa6beta4/metabolismo , Metaloproteinase 8 da Matriz/genética , Metaloproteinase 8 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Comunicação Parácrina , Transporte Proteico , Proteólise , Transdução de Sinais , Fator de Crescimento Transformador beta/metabolismo
14.
Circ Res ; 114(1): 79-91, 2014 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-24103390

RESUMO

RATIONALE: The dramatic upregulation of αvß3-integrin that occurs in the vasculature during tumor growth has long suggested that the endothelial expression of this molecule is an ideal target for antiangiogenic therapy to treat cancer. This discovery led to the development of small-molecule inhibitors directed against αvß3-integrin that are currently in clinical trials. In 2002, we reported that ß3-integrin-knockout mice exhibit enhanced tumor growth and angiogenesis. However, as ß3-integrin is expressed by a wide variety of cells, endothelial cell-specific contributions to tumor angiogenesis are muddied by the use of a global knockout of ß3-integrin function. OBJECTIVE: Our aim was to examine the endothelial-specific contribution ß3-integrin makes to tumor growth and angiogenesis. METHODS AND RESULTS: We have crossed ß3-integrin-floxed (ß3-floxed) mice to 2 endothelial-specific Cre models and examined angiogenic responses in vivo, ex vivo, and in vitro. We show that acute depletion of endothelial ß3-integrin inhibits tumor growth and angiogenesis preventatively, but not in already established tumors. However, the effects are transient, and long-term depletion of the molecule is ineffective. Furthermore, long-term depletion of the molecule correlates with many molecular changes, such as reduced levels of focal adhesion kinase expression and a misbalance in focal adhesion kinase phosphorylation, which may lead to a release from the inhibitory effects of decreased endothelial ß3-integrin expression. CONCLUSIONS: Our findings imply that timing and length of inhibition are critical factors that need to be considered when targeting the endothelial expression of ß3-integrin to inhibit tumor growth and angiogenesis.


Assuntos
Células Endoteliais/metabolismo , Endotélio Vascular/metabolismo , Integrina alfaVbeta3/genética , Neoplasias Experimentais/irrigação sanguínea , Neovascularização Patológica/metabolismo , Animais , Adesão Celular , Linhagem Celular Tumoral , Proliferação de Células , Células Endoteliais/patologia , Endotélio Vascular/patologia , Proteína-Tirosina Quinases de Adesão Focal/genética , Proteína-Tirosina Quinases de Adesão Focal/metabolismo , Integrina alfaVbeta3/metabolismo , Pulmão/irrigação sanguínea , Pulmão/patologia , Camundongos , Camundongos Endogâmicos C57BL , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Neovascularização Patológica/patologia
15.
Neuromodulation ; 19(3): 249-53, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26817797

RESUMO

OBJECTIVES: To assess feasibility and tolerability of long-term distributed therapeutic rTMS for refractory tinnitus, distributed over seven months. MATERIALS AND METHODS: Eight subjects with refractory tinnitus underwent five weekly sessions of 1800 pulses of 1 Hz rTMS targeted toward the temporoparietal junction. Five weeks later (study week 10), subjects meeting predefined responder criteria entered a monthly rTMS treatment phase, for the next five months. Outcome measures were subject satisfaction and compliance, tinnitus severity daily diaries, standardized tinnitus self-rating scales, and adverse events. RESULTS: Subject satisfaction was high, and compliance was virtually 100%. The tinnitus handicap inventory and mini-tinnitus questionnaire scores improved significantly at study week 5 compared with baseline. There were four responders at study week 5; three responders at study week 10; and one responder at study week 30. There were no serious adverse events. CONCLUSIONS: Our study demonstrated that rTMS can be delivered in a distributed schedule that is well-tolerated, feasible and may prove to be clinically beneficial. A long-term distributed rTMS schedule for tinnitus may warrant investigation as an alternative to the short-term aggregated treatment schedules more frequently used previously. For the many varied therapeutic uses of rTMS (established and investigational), treatment schedules are relatively unexplored, and deserve further attention.


Assuntos
Zumbido/terapia , Estimulação Magnética Transcraniana/métodos , Adulto , Idoso , Estudos de Viabilidade , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Inquéritos e Questionários
16.
Breast Cancer Res ; 17: 38, 2015 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-25848906

RESUMO

INTRODUCTION: Matrix metalloproteinase-8 (MMP-8; neutrophil collagenase) is an important regulator of innate immunity that has oncosuppressive actions in numerous tumor types. METHODS: We have intercrossed Mmp8-null mice with the Polyoma virus middle T oncogene-driven (MMTV-PyMT) mouse model of mammary cancer to explore the effects of loss of MMP-8 on the incidence and progression of mammary carcinomas. RESULTS: In this aggressive mouse model of breast cancer, loss of MMP-8 accelerated tumor onset even further, such that 90% of MMTV-PyMT; Mmp8-null female mice were tumor-bearing at the time of weaning. Throughout the 14 weeks of the model, tumor burden increased in homozygous Mmp8-null mice compared to Mmp8-wild-type and -heterozygote animals. Likewise, lung metastasis dramatically increased in the MMTV-PyMT; Mmp8-null mice. Immunohistochemistry revealed that tumors in wild-type, Mmp8-heterozygotes and -null animals had similar vascular density at 8 weeks, but at 10 weeks Mmp8-wild-type tumors had a lower vascularity than their heterozygote and null counterparts. No differences in macrophage infiltration were apparent throughout primary tumor development, though at 10 weeks a drop in neutrophil infiltrates was observed in Mmp8-wild-type tumors. Using quantitative real-time RT-PCR, we tracked the expression of the entire Mmp and Timp gene families, observing a significant decrease in Mmp3 expression in Mmp8-null tumors compared to wild-type and heterozygotes throughout the time course of the model, which was confirmed at the protein level. CONCLUSIONS: These findings provide novel insight into the suppressive action of MMP-8 on mammary tumorigenesis and metastasis, and indicate that the loss of MMP-8 likely has pleiotropic effects on innate immunity and angiogenesis that are reflected in changes in the protease web.


Assuntos
Antígenos Virais de Tumores/genética , Neoplasias Mamárias Experimentais/etiologia , Neoplasias Mamárias Experimentais/patologia , Vírus do Tumor Mamário do Camundongo/genética , Metaloproteinase 8 da Matriz/genética , Infecções por Retroviridae/complicações , Infecções Tumorais por Vírus/complicações , Animais , Transformação Celular Neoplásica , Progressão da Doença , Feminino , Mediadores da Inflamação/metabolismo , Neoplasias Pulmonares/secundário , Metaloproteinase 8 da Matriz/metabolismo , Camundongos , Camundongos Knockout , Família Multigênica , Metástase Neoplásica , Neovascularização Patológica/genética , Infiltração de Neutrófilos
17.
Int J Cancer ; 136(4): E14-26, 2015 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-25099234

RESUMO

The ADAMTS proteinases are a family of secreted, matrix-associated enzymes that have diverse roles in the regulation of tissue organization and vascular homeostasis. Several of the 19 human family members have been identified as having either tumor promoting or suppressing roles. We previously demonstrated that decreased ADAMTS15 expression correlated with a worse clinical outcome in mammary carcinoma (e.g., Porter et al., Int J Cancer 2006;118:1241-7). We have explored the effects of A Disintegrin and Metalloproteinase with Thrombospondin motifs-15 (ADAMTS-15) on the behavior of MDA-MB-231 and MCF-7 breast cancer cells by stable expression of either a wild-type (wt) or metalloproteinase-inactive (E362A) protein. No effects on mammary cancer cell proliferation or apoptosis were observed for either form of ADAMTS-15. However, both forms reduced cell migration on fibronectin or laminin matrices, though motility on a Type I collagen matrix was unimpaired. Knockdown of syndecan-4 attenuated the inhibitory effects of ADAMTS-15 on cell migration. In contrast to its effects on cell migration, wt ADAMTS-15 but not the E362A inactive mutant inhibited endothelial tubulogenesis in 3D collagen gels and angiogenesis in the aortic ring assay. In experimental metastasis assays in nude mice, MDA-MB-231 cells expressing either form of ADAMTS-15 showed reduced spread to the liver, though lung colonization was enhanced for cells expressing wt ADAMTS-15. These studies indicate that extracellular ADAMTS-15 has multiple actions on tumor pathophysiology. Via modulation of cell-ECM interactions, which likely involve syndecan-4, it attenuates mammary cancer cell migration independent of its metalloproteinase activity; however, its antiangiogenic action requires catalytic functionality, and its effects on metastasis in vivo are tissue niche-dependent.


Assuntos
Proteínas ADAM/fisiologia , Neoplasias da Mama/enzimologia , Neoplasias Hepáticas/enzimologia , Proteínas ADAMTS , Proteína ADAMTS1 , Animais , Neoplasias da Mama/patologia , Movimento Celular , Matriz Extracelular/enzimologia , Feminino , Células Endoteliais da Veia Umbilical Humana/fisiologia , Humanos , Neoplasias Hepáticas/secundário , Células MCF-7 , Camundongos Nus , Transplante de Neoplasias , Neovascularização Patológica/enzimologia , Especificidade de Órgãos , Sindecana-4/metabolismo , Microambiente Tumoral
18.
Arch Phys Med Rehabil ; 96(4 Suppl): S114-21, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25461825

RESUMO

OBJECTIVE: To investigate the effects of anodal transcranial direct current stimulation (a-tDCS) intensity on corticospinal excitability and affected muscle activation in individuals with chronic spinal cord injury (SCI). DESIGN: Single-blind, randomized, sham-controlled, crossover study. SETTING: Medical research institute and rehabilitation hospital. PARTICIPANTS: Volunteers (N = 9) with chronic SCI and motor dysfunction in wrist extensor muscles. INTERVENTIONS: Three single session exposures to 20 minutes of a-tDCS (anode over the extensor carpi radialis [ECR] muscle representation on the left primary motor cortex, cathode over the right supraorbital area) using 1 mA, 2 mA, or sham stimulation, delivered at rest, with at least 1 week between sessions. MAIN OUTCOME MEASURES: Corticospinal excitability was assessed with motor-evoked potentials (MEPs) from the ECR muscle using surface electromyography after transcranial magnetic stimulation. Changes in spinal excitability, sensory threshold, and muscle strength were also investigated. RESULTS: Mean MEP amplitude significantly increased by approximately 40% immediately after 2mA a-tDCS (pre: 0.36 ± 0.1 mV; post: 0.47 ± 0.11 mV; P = .001), but not with 1 mA or sham. Maximal voluntary contraction measures remained unaltered across all conditions. Sensory threshold significantly decreased over time after 1mA (P = .002) and 2mA (P = .039) a-tDCS and did not change with sham. F-wave persistence showed a nonsignificant trend for increase (pre: 32% ± 12%; post: 41% ± 10%; follow-up: 46% ± 12%) after 2 mA stimulation. No adverse effects were reported with any of the experimental conditions. CONCLUSIONS: The a-tDCS can transiently raise corticospinal excitability to affected muscles in patients with chronic SCI after 2 mA stimulation. Sensory perception can improve with both 1 and 2 mA stimulation. This study gives support to the safe and effective use of a-tDCS using small electrodes in patients with SCI and highlights the importance of stimulation intensity.


Assuntos
Potencial Evocado Motor/fisiologia , Tratos Piramidais/fisiopatologia , Traumatismos da Medula Espinal/reabilitação , Estimulação Transcraniana por Corrente Contínua/métodos , Adulto , Doença Crônica , Estudos Cross-Over , Eletromiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/fisiopatologia , Modalidades de Fisioterapia , Método Simples-Cego , Estimulação Transcraniana por Corrente Contínua/efeitos adversos , Estimulação Magnética Transcraniana/métodos , Punho/fisiopatologia
19.
J Biol Chem ; 288(23): 16282-16294, 2013 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-23632023

RESUMO

Matrix metalloproteinase 8 (MMP-8) is a tumor-suppressive protease that cleaves numerous substrates, including matrix proteins and chemokines. In particular, MMP-8 proteolytically activates IL-8 and, thereby, regulates neutrophil chemotaxis in vivo. We explored the effects of expression of either a WT or catalytically inactive (E198A) mutant version of MMP-8 in human breast cancer cell lines. Analysis of serum-free conditioned media from three breast cancer cell lines (MCF-7, SK-BR-3, and MDA-MB-231) expressing WT MMP-8 revealed elevated levels of IL-6 and IL-8. This increase was mirrored at the mRNA level and was dependent on MMP-8 catalytic activity. However, sustained expression of WT MMP-8 by breast cancer cells was non-permissive for long-term growth, as shown by reduced colony formation compared with cells expressing either control vector or E198A mutant MMP-8. In long-term culture of transfected MDA-MB-231 cells, expression of WT but not E198A mutant MMP-8 was lost, with IL-6 and IL-8 levels returning to base line. Rare clonal isolates of MDA-MB-231 cells expressing WT MMP-8 were generated, and these showed constitutively high levels of IL-6 and IL-8, although production of the interleukins was no longer dependent upon MMP-8 activity. These studies support a causal connection between MMP-8 activity and the IL-6/IL-8 network, with an acute response to MMP-8 involving induction of the proinflammatory mediators, which may in part serve to compensate for the deleterious effects of MMP-8 on breast cancer cell growth. This axis may be relevant to the recognized ability of MMP-8 to orchestrate the innate immune system in inflammation in vivo.


Assuntos
Neoplasias da Mama/metabolismo , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Interleucina-6/biossíntese , Interleucina-8/biossíntese , Metaloproteinase 8 da Matriz/biossíntese , Proteínas de Neoplasias/biossíntese , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Feminino , Humanos , Mediadores da Inflamação/metabolismo , Interleucina-6/genética , Interleucina-8/genética , Metaloproteinase 8 da Matriz/genética , Proteínas de Neoplasias/genética
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA