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1.
Ann Clin Transl Neurol ; 8(2): 308-320, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33350601

RESUMO

OBJECTIVE: The expanding power and accessibility of personal technology provide an opportunity to reduce burdens and costs of traditional clinical site-centric therapeutic trials in Parkinson's disease and generate novel insights. The value of this approach has never been more evident than during the current COVID-19 pandemic. We sought to (1) establish and implement the infrastructure for longitudinal, virtual follow-up of clinical trial participants, (2) compare changes in smartphone-based assessments, online patient-reported outcomes, and remote expert assessments, and (3) explore novel digital markers of Parkinson's disease disability and progression. METHODS: Participants from two recently completed phase III clinical trials of inosine and isradipine enrolled in Assessing Tele-Health Outcomes in Multiyear Extensions of Parkinson's Disease trials (AT-HOME PD), a two-year virtual cohort study. After providing electronic informed consent, individuals complete annual video visits with a movement disorder specialist, smartphone-based assessments of motor function and socialization, and patient-reported outcomes online. RESULTS: From the two clinical trials, 226 individuals from 42 states in the United States and Canada enrolled. Of these, 181 (80%) have successfully downloaded the study's smartphone application and 161 (71%) have completed patient-reported outcomes on the online platform. INTERPRETATION: It is feasible to conduct a large-scale, international virtual observational study following the completion of participation in brick-and-mortar clinical trials in Parkinson's disease. This study, which brings research to participants, will compare established clinical endpoints with novel digital biomarkers and thereby inform the longitudinal follow-up of clinical trial participants and design of future clinical trials.


Assuntos
Aplicativos Móveis , Doença de Parkinson/fisiopatologia , Medidas de Resultados Relatados pelo Paciente , Projetos de Pesquisa , Smartphone , Telemedicina , Comunicação por Videoconferência , COVID-19 , Canadá , Ensaios Clínicos como Assunto , Progressão da Doença , Seguimentos , Humanos , Estudos Longitudinais , SARS-CoV-2 , Estados Unidos
2.
Br J Radiol ; 87(1042): 20140100, 2014 10.
Artigo em Inglês | MEDLINE | ID: mdl-25062448

RESUMO

OBJECTIVE: To compare the degree of small bowel distension achieved by 3% sorbitol, a high osmolarity solution, and a psyllium-based bulk fibre as oral contrast agents (OCAs) in MR enterography (MRE). METHODS: This retrospective study was approved by our institutional review board. A total of 45 consecutive normal MRE examinations (sorbitol, n = 20; psyllium, n = 25) were reviewed. The patients received either 1.5 l of 3% sorbitol or 2 l of 1.6 g kg(-1) psyllium prior to imaging. Quantitative small bowel distension measurements were taken in five segments: proximal jejunum, distal jejunum, proximal ileum, distal ileum and terminal ileum by two independent radiologists. Distension in these five segments was also qualitatively graded from 0 (very poor) to 4 (excellent) by two additional independent radiologists. Statistical analysis comparing the groups and assessing agreement included intraclass coefficients, Student's t-test and Mann-Whitney U-test. RESULTS: Small bowel distension was not significantly different in any of the five small bowel segments between the use of sorbitol and psyllium as OCAs in both the qualitative (p = 0.338-0.908) and quantitative assessments (p = 0.083-0.856). The mean bowel distension achieved was 20.1 ± 2.2 mm for sorbitol and 19.8 ± 2.5 mm for psyllium (p = 0.722). Visualization of the ileum was good or excellent in 65% of the examinations in both groups. CONCLUSION: Sorbitol and psyllium are not significantly different at distending the small bowel and both may be used as OCAs for MRE studies. ADVANCES IN KNOWLEDGE: This is the first study to directly compare the degree of distension in MRE between these two common, readily available and inexpensive OCAs.


Assuntos
Meios de Contraste , Intestino Delgado/efeitos dos fármacos , Imageamento por Ressonância Magnética , Psyllium , Sorbitol , Administração Oral , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Meios de Contraste/administração & dosagem , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Concentração Osmolar , Polissacarídeos , Psyllium/administração & dosagem , Estudos Retrospectivos , Sorbitol/administração & dosagem , Adulto Jovem
3.
Eur J Radiol ; 83(9): 1620-5, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24976500

RESUMO

OBJECTIVE: To determine the change in apparent diffusion coefficient (ADC) of uterine fibroids following uterine fibroid embolisation (UFE), and if the ADC change correlates with either volume loss or degree of contrast enhancement post-UFE. MATERIALS AND METHODS: This study was approved by our institutional review board with waiver of consent. The pelvic MRI examinations, including diffusion-weighted MRI (DWI) using 4 b-values, of 50 consecutive patients prior to and 6 months post-UFE were analyzed. The volume, ADC and amount of enhancement were calculated for each fibroid both pre- and post-UFE. The percent residual enhancement for each fibroid was categorized as either: no (0-1%) residual enhancement or residual (>1%) enhancement. Statistical analysis compared ADC, enhancement and volume for each fibroid pre- and post-UFE using paired t-tests and Pearson correlation coefficients. RESULTS: The mean ADC of all (n=88) fibroids pre-UFE was 1.30±0.20×10(-3)mm(2)/s, and increased to 1.68±0.24×10(-3)mm(2)/s post-UFE (p<0.0001). Lower pre-UFE ADC correlated with greater ADC change post-UFE (r=-0.50; p<0.0001). There was no correlation between ADC change and volume change post-UFE (r=0.07; p=0.59). However, fibroids with no residual enhancement post-UFE had larger ADC change than those with residual enhancement (p=0.003). CONCLUSION: The ADC of fibroids rises post-UFE. ADC change post-UFE is associated with the degree of loss of enhancement and may therefore be valuable in predicting response to treatment in pre-procedural counseling.


Assuntos
Imagem de Difusão por Ressonância Magnética/métodos , Embolização Terapêutica/métodos , Leiomioma/diagnóstico , Leiomioma/terapia , Neoplasias Uterinas/diagnóstico , Neoplasias Uterinas/terapia , Adulto , Meios de Contraste , Feminino , Humanos , Aumento da Imagem/métodos , Meglumina/análogos & derivados , Pessoa de Meia-Idade , Compostos Organometálicos , Resultado do Tratamento , Útero/patologia
4.
Pancreatology ; 14(4): 268-74, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25062875

RESUMO

BACKGROUND/OBJECTIVES: To compare pancreas volume (PV) measurement using MRI-based planimetry in patients with Type 2 diabetes mellitus (DM) to PV in normoglycemic individuals. METHODS: Our institutional review board granted approval of this retrospective study with waiver of informed consent. We searched 2296 consecutive abdominal MRI studies performed at our hospital on patients with no pancreas pathology between September 1, 2010 and February 28, 2013, for those who also had a fasting plasma glucose and/or hemoglobin A1C within six months of the MRI examination. For those patients who met biochemical criteria for DM, we used medication and clinical records to confirm that 32 of these patients had Type 2 DM. The pancreas contours of 32 Type 2 diabetics and 50 normoglycemic individuals were then traced on non-gadolinium T1-weighted 3D fat suppressed gradient echo images by a radiologist trained in abdominal MRI to calculate PV. PV index (PVI) was calculated as PV/weight to adjust PV for each patient's weight. PVs and PVIs in both cohorts were compared using t-tests and regression models correcting for weight, age and gender. RESULTS: Patients with Type 2 DM had significantly lower PVs than normoglycemic individuals (72.7 ± 20.7 cm(3) versus 89.6 ± 22.7 cm(3), p < 0.001), and significantly lower PVIs (1.0 ± 0.3 cm(3)/kg versus 1.3 ± 0.3 cm(3)/kg, p < 0.001). Using regression models, we found that given the same age, weight and gender, the PV in a patient with Type 2 DM was 17.9 mL (20%) lower compared to a normoglycemic individual (p < 0.001). CONCLUSION: PV is reduced in Type 2 DM compared to normoglycemic individuals and can be measured using MRI without contrast injection.


Assuntos
Diabetes Mellitus Tipo 2/patologia , Imageamento por Ressonância Magnética/métodos , Pâncreas/patologia , Adulto , Idoso , Anatomia Transversal , Glicemia/metabolismo , Estudos de Coortes , Feminino , Humanos , Imageamento Tridimensional , Masculino , Pessoa de Meia-Idade , Imagens de Fantasmas , Estudos Retrospectivos
5.
J Biol Chem ; 284(43): 29893-904, 2009 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-19625257

RESUMO

The pleiotropic cytokines, transforming growth factor beta1 (TGFbeta1), and tumor necrosis factor (TNF) play critical roles in tissue homeostasis in response to injury and are implicated in multiple human diseases and cancer. We reported that the loss of Timp3 (tissue inhibitor of metalloproteinase 3) leads to abnormal TNF signaling and cardiovascular function. Here we show that parallel deregulation of TGFbeta1 and TNF signaling in Timp3(-/-) mice amplifies their cross-talk at the onset of cardiac response to mechanical stress (pressure overload), resulting in fibrosis and early heart failure. Microarray analysis showed a distinct gene expression profile in Timp3(-/-) hearts, highlighting activation of TGFbeta1 signaling as a potential mechanism underlying fibrosis. Neonatal cardiomyocyte-cardiofibroblast co-cultures were established to measure fibrogenic response to agonists known to be induced following mechanical stress in vivo. A stronger response occurred in neonatal Timp3(-/-) co-cultures, as determined by increased Smad signaling and collagen expression, due to increased TNF processing and precocious proteolytic maturation of TGFbeta1 to its active form. The relationship between TGFbeta1 and TNF was dissected using genetic and pharmacological manipulations. Timp3(-/-)/Tnf(-/-) mice had lower TGFbeta1 than Timp3(-/-), and anti-TGFbeta1 antibody (1D11) negated the abnormal TNF response, indicating their reciprocal stimulatory effects, with each manipulation abolishing fibrosis and improving heart function. Thus, TIMP3 is a common innate regulator of TGFbeta1 and TNF in tissue response to injury. The matrix-bound TIMP3 balances the anti-inflammatory and proinflammatory processes toward constructive tissue remodeling.


Assuntos
Fibrose Endomiocárdica/metabolismo , Transdução de Sinais , Inibidor Tecidual de Metaloproteinase-3 , Fator de Crescimento Transformador beta1/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Animais , Células Cultivadas , Técnicas de Cocultura , Colágeno/biossíntese , Colágeno/genética , Fibrose Endomiocárdica/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/genética , Humanos , Camundongos , Camundongos Knockout , Análise de Sequência com Séries de Oligonucleotídeos , Proteínas Smad/genética , Proteínas Smad/metabolismo , Fator de Crescimento Transformador beta1/genética , Fator de Necrose Tumoral alfa/genética
6.
J Proteome Res ; 5(5): 1143-54, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16674103

RESUMO

Transforming growth factor-beta (TGF-beta) induces epithelial-mesenchymal transition (EMT) of epithelial cells in both normal embryonic development and certain pathological contexts. Here, we show that TGF-beta induced-EMT in human lung cancer cells (A549; adenocarcinoma cells) mediates tumor cell migration and invasion phenotypes. To gain insights into molecular events during EMT, we employed a global stable isotope labeled profiling strategy using iTRAQ reagents, followed by 2DLC-MS/MS, which identified a total of 51 differentially expressed proteins during EMT; 29 proteins were up-regulated and 22 proteins were down-regulated. Down-regulated proteins were predominantly enzymes involved in regulating nutrient or drug metabolism. The majority of the TGF-beta-induced proteins (such as tropomyosins, filamin A, B, & C, integrin-beta1, heat shock protein27, transglutaminase2, cofilin, 14-3-3 zeta, ezrin-radixin-moesin) are involved in the regulation of cell migration, adhesion and invasion, suggesting the acquisition of a invasive phenotype.


Assuntos
Adenocarcinoma/patologia , Neoplasias Pulmonares/patologia , Espectrometria de Massas/métodos , Proteínas/análise , Proteômica/métodos , Adenocarcinoma/tratamento farmacológico , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Cromatografia Líquida/métodos , Células Epiteliais/patologia , Humanos , Processamento de Imagem Assistida por Computador , Neoplasias Pulmonares/tratamento farmacológico , Mesoderma/patologia , Invasividade Neoplásica , Fenótipo , Proteínas/efeitos dos fármacos , Proteínas/metabolismo , Software , Fator de Crescimento Transformador beta/farmacologia
7.
Neoplasia ; 7(3): 294-301, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15799829

RESUMO

Activation of peroxisome proliferator-activated receptor-gamma (PPAR-gamma) results in inhibition of tumor growth in various types of cancers, but the mechanism(s) by which PPAR-gamma induces growth arrest has not been completely defined. In a recent study, we demonstrate that treatment of A549 (human non small cell lung cancer cell line) tumor-bearing SCID mice with PPAR-gamma ligands troglitazone (Tro) and pioglitazone significantly inhibits primary tumor growth. In this study, immunohistochemical analysis of Tro-treated and Pio-treated tumors with factor VIII antibody revealed a significant reduction in blood vessel density compared to tumors in control animals, suggesting inhibition of angiogenesis. Further analysis showed that treatment of A549 cells in vitro with Tro or transient transfection of A549 cells with constitutively active PPAR-gamma (VP16-PPAR-gamma) construct blocked the production of the angiogenic ELR+CXC chemokines IL-8 (CXCL8), ENA-78 (CXCL5), and Gro-alpha (CXCL1). Similarly, an inhibitor of NF-kappa B activation (PDTC) also blocked CXCL8, CXCL5, and CXCL1 production, consistent with their NF-kappa B-dependent regulation. Conditioned media from A549 cells induce human microvascular endothelial cell (HMVEC) chemotaxis. However, conditioned media from Tro-treated A549 cells induced significantly less HMVEC chemotaxis compared to untreated A549 cells. Furthermore, PPAR-gamma activation inhibited NF-kappa B transcriptional activity, as assessed by TransAM reporter gene assay. Collectively, our data suggest that PPAR-gamma ligands can inhibit tumor-associated angiogenesis by blocking the production of ELR+CXC chemokines, which is mediated through antagonizing NF-kappaB activation. These antiangiogenic effects likely contribute to the inhibition of primary tumor growth by PPAR-gamma ligands.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/patologia , Neovascularização Patológica , PPAR gama/metabolismo , Prolina/análogos & derivados , Motivos de Aminoácidos , Animais , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Células Cultivadas , Quimiocina CXCL1 , Quimiocina CXCL11 , Quimiocina CXCL5 , Quimiocinas CXC/metabolismo , Quimiocinas CXC/farmacologia , Quimiotaxia , Cromanos/farmacologia , Meios de Cultivo Condicionados/farmacologia , Relação Dose-Resposta a Droga , Endotélio Vascular/citologia , Ensaio de Imunoadsorção Enzimática , Fator VIII/química , Humanos , Imuno-Histoquímica , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Interleucina-8/metabolismo , Ligantes , Neoplasias Pulmonares/metabolismo , Camundongos , Camundongos SCID , Microcirculação , NF-kappa B/metabolismo , Transplante de Neoplasias , Pioglitazona , Prolina/farmacologia , Tiazolidinedionas/farmacologia , Tiocarbamatos/farmacologia , Transfecção , Troglitazona
8.
Int J Hematol ; 75(3): 289-97, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11999358

RESUMO

Labeling index (LI), apoptosis, levels of 2 pro-apoptotic cytokines tumor necrosis factor-alpha (TNF-alpha) and transforming growth factor-beta(TGF-beta), and the number of monocyte/macrophage cells that are the likely source of the cytokines were simultaneously measured in plastic-embedded bone marrow (BM) biopsy sections of 145 patients with myelodysplastic syndromes (MDS). TNF-alpha was correlated with TGF-beta (P = .001) and with monocyte/macrophage cells (P = .003). Patients with excess blasts in their marrows had a higher TGF-beta level (P = .01) and monocyte/macrophage number (P = .05). In a linear regression model,TGF-beta emerged as the most significant biological difference between patients who have excess of blasts and those who do not (P = .01). We conclude that in addition to TNF-alpha, TGF-beta also plays a significant role in the initiation and pathogenesis of MDS, and that a more precise definition of its role will likely identify better preventive and therapeutic strategies.


Assuntos
Apoptose , Células da Medula Óssea/patologia , Citocinas/análise , Macrófagos/patologia , Monócitos/patologia , Síndromes Mielodisplásicas/patologia , Anemia Refratária/patologia , Anemia Refratária com Excesso de Blastos/patologia , Animais , Divisão Celular , Feminino , Humanos , Leucemia Mielomonocítica Crônica/patologia , Masculino , Análise de Regressão , Fase S , Fator de Crescimento Transformador beta/análise , Fator de Necrose Tumoral alfa/análise
9.
Br J Haematol ; 116(3): 564-75, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11849212

RESUMO

Mitochondria (mt) play an important role in both apoptosis and haem synthesis. The present study was conducted to determine DNA mutations in mitochondrial encoded cytochrome c-oxidase I and II genes. Bone marrow (BM) biopsy and aspirate, peripheral blood (PB) and buccal smear samples were collected from 20 myelodysplastic syndrome (MDS) patients and 10 age-matched controls. Cytochrome c-oxidase I (CO I) and II (CO II) genes were amplified using polymerase chain reaction and sequenced. CO I mutations were found in 13/20 MDS patients and the CO II gene in 2/10 normal and 12/20 MDS samples, irrespective of MDS subtype. Mutations were substitutional, deletional and insertional. CO I mutations were most common at nucleotide positions 7264 (25%) and 7289 (15%), and CO II mutations were most common at nucleotide positions 7595 (40%) and 7594 (30%), suggesting the presence of potential 'hot-spots'. Mutations were not found in buccal smears of MDS patients and were significantly higher in MDS samples compared with age-matched controls in all cell fractions (P < 0.05), with bone marrow high-density fraction (BMHDF) showing a higher mutation rate than other fractions (P < 0.05). MDS marrows showed higher levels of apoptosis than normal controls (P < 0.05), and apoptosis in BMHDF was directly related to cytochrome c-oxidase I gene mutations (P < 0.05). Electron microscopy revealed apoptosis affecting all haematopoietic lineages with highly abnormal, iron-laden mitochondria. These results suggest a role for mt-DNA mutations in the excessive apoptosis and resulting cytopenias of MDS patients.


Assuntos
DNA Mitocondrial/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Mitocôndrias/enzimologia , Mutação , Síndromes Mielodisplásicas/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Apoptose , Células da Medula Óssea/enzimologia , Células da Medula Óssea/ultraestrutura , Feminino , Humanos , Marcação In Situ das Extremidades Cortadas , Masculino , Pessoa de Meia-Idade , Mitocôndrias/ultraestrutura , Síndromes Mielodisplásicas/enzimologia , Síndromes Mielodisplásicas/patologia
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