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1.
Games Health J ; 12(4): 323-329, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36944143

RESUMO

Objective: Pediatric hemiplegia is associated with wide-ranging deficits in arm and hand motor function, neg-atively impacting participation in daily occupations and quality of life. This study investigated whether performance measures generated during therapy videogame play by children with hemiplegia can be valid indicators of upper extremity motor function. Materials and Methods: Ten children with hemiplegia used a custom therapy game system alternatively using their affected and non-affected hand to provide motion capture data that spans a wide range of motor function status. The children also completed a series of standardized outcome measure assessments with each hand, including the Quality of Upper Extremity Skills Test, the Jebsen Taylor Hand Function Test, and the Wolf Motor Function Test. Results: Statistical analysis using the nonparametric Spearman rank correlation revealed high and significant correlation between videogame-derived motion capture measures, characterizing the speed and smoothness of movements, and the standardized outcome measure assessments. Conclusion: The results suggest that a low-cost motion capture system can be used to monitor a child's motor function status and progress during a therapy program.


Assuntos
Paralisia Cerebral , Jogos de Vídeo , Criança , Humanos , Hemiplegia , Qualidade de Vida , Captura de Movimento , Extremidade Superior
2.
OTJR (Thorofare N J) ; 43(3): 446-456, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36960762

RESUMO

This rater-blinded, randomized control trial (RCT) investigated the effectiveness of a Glove Rehabilitation Application for Stroke Patients (GRASP) virtual reality home exercise program (HEP) for upper extremity (UE) motor recovery following stroke. The GRASP system facilitates the use of the affected UE in simulated instrumental activities of daily living (IADLs). Participants were asked to use the system at home in asynchronous telehealth sessions 4 times per week over 8 weeks. A non-blinded occupational therapist (OT) provided synchronous telehealth visits biweekly. Analysis comparing pre- and post-assessment results for the Fugl-Meyer UE assessment (FMUE) shows a clinically important and statistically significant between-group difference for participants completing the GRASP HEP protocol compared with usual and customary care controls. Statistically significant and clinically important differences were also found in Motor Activity Log (MAL) scores. This evidence provides support for the effectiveness of home-based, IADL-focused, virtual reality therapy with telehealth support.


Assuntos
Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Telemedicina , Realidade Virtual , Humanos , Recuperação de Função Fisiológica , Extremidade Superior , Reabilitação do Acidente Vascular Cerebral/métodos , Resultado do Tratamento
3.
Am J Occup Ther ; 74(3): 7403205150p1-7403205150p9, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32365321

RESUMO

IMPORTANCE: Fieldwork educators receive little or no formal training for student supervision and have sought inexpensive, flexible, online options for role-specific continuing education. OBJECTIVE: To investigate the use of online journal clubs to enhance fieldwork educator role competency. DESIGN: Mixed-methods study with a prospective cohort design; 5-wk intervention with 6-mo follow-up. SETTING: Online asynchronous message board system distributed to fieldwork educators affiliated with two occupational therapy programs. PARTICIPANTS: Academic fieldwork coordinators from two universities facilitated online journal clubs for fieldwork educators. Fourteen fieldwork educators participated in the 5-wk journal club, which included reading an article, engaging in online discussion, and creating a personal application plan. RESULTS: Participants demonstrated strong engagement in the online journal club. Postsurvey results revealed strong and positive feedback related to ease of use, relevance of learning, and satisfaction with the experience. At the 6-mo follow-up, 11 of the 14 participants reported implementing a new strategy to support the fieldwork education process, and all reported that the strategy had been helpful. CONCLUSIONS AND RELEVANCE: The use of an online journal club was effective as a method for sharing evidence about the fieldwork educator role and supporting knowledge translation. WHAT THIS ARTICLE ADDS: Online journal clubs can be an effective tool for providing role-specific training in diverse practice settings and parts of the country.


Assuntos
Terapia Ocupacional/educação , Aprendizagem Baseada em Problemas , Leitura , Humanos , Publicações Periódicas como Assunto , Estudos Prospectivos , Estudantes
4.
OTJR (Thorofare N J) ; 39(2): 81-89, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30885076

RESUMO

Hand motor control deficits following stroke can diminish the ability of patients to participate in daily activities. This study investigated the criterion validity of upper extremity (UE) performance measures automatically derived from sensor data during manual practice of simulated instrumental activities of daily living (IADLs) within a virtual environment. A commercial glove orthosis was specially instrumented with motion tracking sensors to enable patients to interact, through functional UE movements, with a computer-generated virtual world using the SaeboVR software system. Fifteen stroke patients completed four virtual IADL practice sessions, as well as a battery of gold-standard assessments of UE motor and hand function. Statistical analysis using the nonparametric Spearman rank correlation reveals high and significant correlation between virtual world-derived measures and the gold-standard assessments. The results provide evidence that performance measures generated during manual interactions with a virtual environment can provide a valid indicator of UE motor status.


Assuntos
Aparelhos Ortopédicos , Paresia/reabilitação , Reabilitação do Acidente Vascular Cerebral , Realidade Virtual , Atividades Cotidianas , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Terapia Ocupacional , Recuperação de Função Fisiológica , Resultado do Tratamento
5.
IEEE Trans Neural Syst Rehabil Eng ; 26(1): 252-260, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29324411

RESUMO

A study was conducted to investigate the effectiveness of virtual activities of daily living (ADL) practice using the SaeboVR software system for the recovery of upper extremity (UE) motor function following stroke. The system employs Kinect sensor-based tracking to translate human UE motion into the anatomical pose of the arm of the patient's avatar within a virtual environment, creating a virtual presence within a simulated task space. Patients gain mastery of 12 different integrated activities while traversing a metaphorical "road to recovery" that includes thematically linked levels and therapist-selected difficulty settings. Clinical trials were conducted under the study named Virtual Occupational Therapy Application. A total of 15 chronic phase stroke survivors completed a protocol involving three sessions per week over eight weeks, during which they engaged in repetitive task practice through performance of the virtual ADLs. Results show a clinically important improvement and statistically significant difference in Fugl-Meyer UE assessment scores in the study population of chronic stroke survivors over the eight-week interventional period compared with a non-interventional control period of equivalent duration. Statistically significant and clinically important improvements are also found in the wolf motor function test scores. These results provide new evidence for the use of virtual ADL practice as a tool for UE therapy for stroke patients. Limitations of the study include non-blinded assessments and the possibility of selection and/or attrition bias.


Assuntos
Atividades Cotidianas , Reabilitação do Acidente Vascular Cerebral/métodos , Extremidade Superior , Realidade Virtual , Idoso , Idoso de 80 Anos ou mais , Braço , Simulação por Computador , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Movimento (Física) , Destreza Motora , Terapia Ocupacional/métodos , Recuperação de Função Fisiológica , Sobreviventes , Resultado do Tratamento
6.
Occup Ther Health Care ; 32(1): 72-78, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29265958

RESUMO

Academic programs are tasked with the responsibility of providing support for fieldwork educators who provide training for their students. This article describes a pilot program wherein nine fieldwork educators participated in a weekly online journal club to gain increased knowledge of evidence-based supervision strategies. Program assessment indicated that an online journal club was feasible and well accepted by the fieldwork educators and that the participants valued the opportunity to connect and discuss the role with other fieldwork educators.


Assuntos
Preceptoria/métodos
7.
Am J Occup Ther ; 69(3): 6903290030p1-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25871604

RESUMO

OBJECTIVE: The purpose of this study was to investigate the behavioral intention to use (BIU) regarding a virtual system for practicing instrumental activities of daily living (IADLs) among people with stroke. METHOD: Fourteen people who had sustained a stroke used a virtual world-based system over four sessions to participate in virtual occupations of preparing meals and putting away groceries. To investigate intention to use the technology, participants responded to a questionnaire based on the Technology Acceptance Model and were interviewed about the experience. RESULTS: Analysis of questionnaire responses revealed favorable attitudes toward the technology and statistically significant correlations between these attitudes and positive BIU. Analysis of qualitative data revealed four themes to support system use: Use of the affected arm increased, the virtual practice was enjoyable, the technology was user-friendly, and the system reflected real-life activities. CONCLUSION: This study shows that participants reported a positive BIU for the virtual system for practicing IADLs.


Assuntos
Atividades Cotidianas , Atitude Frente aos Computadores , Intenção , Reabilitação do Acidente Vascular Cerebral , Interface Usuário-Computador , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Aceitação pelo Paciente de Cuidados de Saúde , Prática Psicológica , Inquéritos e Questionários
8.
IEEE Trans Neural Syst Rehabil Eng ; 23(2): 287-96, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25265612

RESUMO

A study was conducted to investigate the criterion validity of measures of upper extremity (UE) motor function derived during practice of virtual activities of daily living (ADLs). Fourteen hemiparetic stroke patients employed a Virtual Occupational Therapy Assistant (VOTA), consisting of a high-fidelity virtual world and a Kinect™ sensor, in four sessions of approximately one hour in duration. An unscented Kalman Filter-based human motion tracking algorithm estimated UE joint kinematics in real-time during performance of virtual ADL activities, enabling both animation of the user's avatar and automated generation of metrics related to speed and smoothness of motion. These metrics, aggregated over discrete sub-task elements during performance of virtual ADLs, were compared to scores from an established assessment of UE motor performance, the Wolf Motor Function Test (WMFT). Spearman's rank correlation analysis indicates a moderate correlation between VOTA-derived metrics and the time-based WMFT assessments, supporting the criterion validity of VOTA measures as a means of tracking patient progress during an UE rehabilitation program that includes practice of virtual ADLs.


Assuntos
Atividades Cotidianas , Braço/fisiopatologia , Movimento , Paresia/diagnóstico , Paresia/fisiopatologia , Interface Usuário-Computador , Idoso , Idoso de 80 Anos ou mais , Diagnóstico por Computador/métodos , Técnicas de Diagnóstico Neurológico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Monitorização Ambulatorial/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
9.
PLoS One ; 5(2): e9065, 2010 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-20140090

RESUMO

BACKGROUND: Cardiovascular disease (CVD) susceptibility differs between men and women and varies with ethnicity. This variability is not entirely explained by conventional CVD risk factors. We examined differences in circulating levels of 47 novel protein markers of CVD in 2561 men and women of African-American (AA) and non-Hispanic White (NHW) ethnicity, enrolled at geographically distinct sites. METHODOLOGY/PRINCIPAL FINDINGS: Participants (1,324 AAs, mean age 63.5 y, 71% women; 1,237 NHWs, mean age 58.9 y, 57% women) belonged to sibships ascertained on the basis of hypertension. Solid-phase immunoassays and immunoturbidometric, clot-based, chromogenic, and electrophoretic assays were used to measure the 47 protein markers in plasma or serum. Marker levels were log transformed and outliers were adjusted to within 4 SD. To identify markers independently associated with sex or ethnicity, we employed multivariable regression analyses that adjusted for conventional risk factors, prior history of CVD, medication use and lifestyle factors (physical activity, alcohol consumption and education). Generalized estimating equations were used to correct for intrafamilial correlations. After adjustment for the above covariates, female sex was associated with higher levels of 29 markers and lower levels of 6 markers. Female sex was independently associated with higher levels of several inflammatory markers as well as lipoproteins, adipokines, natriuretic peptides, vasoconstrictor peptides and markers of calcification and thrombosis. AA ethnicity was associated with higher levels of 19 markers and lower levels of 6 markers, including higher levels of several inflammatory makers, higher leptin and lower adiponectin levels, lower levels of vasodilator-natriuretic peptides, higher levels of vasoconstrictor-antidiuretic peptides and markers of calcification and thrombosis. CONCLUSIONS/SIGNIFICANCE: Plasma levels of several novel protein markers of CVD differ significantly in the context of sex and ethnicity. These results have implications for individualized CVD risk assessment.


Assuntos
Biomarcadores/sangue , Negro ou Afro-Americano/estatística & dados numéricos , Doenças Cardiovasculares/sangue , População Branca/estatística & dados numéricos , Idoso , Arteriosclerose/sangue , Arteriosclerose/diagnóstico , Arteriosclerose/etnologia , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/etnologia , Feminino , Humanos , Imunoensaio/métodos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Proteoma/análise , Proteômica , Análise de Regressão , Fatores de Risco , Sensibilidade e Especificidade , Fatores Sexuais
10.
Clin Chem ; 56(2): 186-93, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19959625

RESUMO

BACKGROUND: The measurement of multiple protein biomarkers may refine risk stratification in clinical settings. This concept has stimulated development of multiplexed immunoassay platforms that provide multiple, parallel protein measurements on the same specimen. CONTENT: We provide an overview of antibody-based multiplexed immunoassay platforms and discuss technical and operational challenges. Multiplexed immunoassays use traditional immunoassay principles in which high-affinity capture ligands are immobilized in parallel arrays in either planar format or on microspheres in suspension. Development of multiplexed immunoassays requires rigorous validation of assay configuration and analytical performance to minimize assay imprecision and inaccuracy. Challenges associated with multiplex configuration include selection and immobilization of capture ligands, calibration, interference between antibodies and proteins and assay diluents, and compatibility of assay limits of quantification. We discuss potential solutions to these challenges. Criteria for assessing analytical multiplex assay performance include the range of linearity, analytical specificity, recovery, and comparison to a quality reference method. Quality control materials are not well developed for multiplexed protein immunoassays, and algorithms for interpreting multiplex quality control data are needed. SUMMARY: Technical and operational challenges have hindered implementation of multiplexed assays in clinical settings. Formal procedures that guide multiplex assay configuration, analytical validation, and quality control are needed before broad application of multiplexed arrays can occur in the in vitro diagnostic market.


Assuntos
Anticorpos/química , Biomarcadores/sangue , Imunoensaio/métodos , Proteínas/análise
11.
Atherosclerosis ; 206(2): 575-80, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19423112

RESUMO

Osteoprotegerin (OPG), a member of tumor necrosis factor receptor superfamily, has been implicated in vascular disease. We investigated the association of serum OPG with the ankle-brachial index (ABI) and urine albumin:creatinine ratio (UACR), in a bi-ethnic cohort of 1324 African-Americans (mean age 64 years, 71% women) and 1237 non-Hispanic whites (mean age 59 years, 57% women) belonging to hypertensive sibships. Serum levels of OPG were measured by solid phase sandwich immunoassay. ABI was measured using a standard protocol and peripheral arterial disease (PAD) defined as ABI<0.90. UACR was expressed as mg albumin/gm creatinine. Multivariable regression analysis using generalized estimating equations (GEE) were performed to assess whether serum OPG levels were associated with ABI and UACR. After adjustment for conventional risk factors (age, sex, diabetes, waist circumference, history of smoking, total and HDL cholesterol, hypertension), prior history of myocardial infarction or stroke, and medication (renin-angiotensin-aldosterone system inhibitors, statins, aspirin, estrogen) use, higher OPG levels were significantly associated with lower ABI and higher UACR in African-Americans (P=0.001 and P<0.0001, respectively) and non-Hispanic whites (P=0.017 and P=0.002, respectively); the association remained significant after further adjustment for plasma C-reactive protein (CRP) in both ethnic groups. In multivariable logistic regression analysis, higher OPG levels were associated with PAD in African-Americans, independent of the covariates listed above (P=0.026); the association remained significant after additional adjustment for plasma CRP (P=0.047). In non-Hispanic whites, the association of higher OPG levels with PAD was of borderline significance after adjustment for the relevant covariates (P=0.106). We conclude that higher OPG levels are associated with lower ABI and higher UACR, independent of conventional risk factors and plasma CRP.


Assuntos
Albuminúria/urina , Índice Tornozelo-Braço , Creatinina/urina , Osteoprotegerina/sangue , Negro ou Afro-Americano , Idoso , Proteína C-Reativa/metabolismo , Estudos de Coortes , Feminino , Humanos , Hipertensão/sangue , Masculino , Pessoa de Meia-Idade , Análise de Regressão , População Branca
12.
Clin Chem ; 55(6): 1092-9, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19372187

RESUMO

BACKGROUND: Multiplex arrays are increasingly used for measuring protein biomarkers. Advantages of this approach include specimen conservation, limited sample handling, and decreased time and cost, but the challenges of optimizing assay format for each protein, selecting common dilution factors, and establishing robust quality control algorithms are substantial. Here, we use measurements of 15 protein biomarkers from a large study to illustrate processing, analytic, and quality control issues with multiplexed immunoassays. METHODS: We contracted with ThermoScientific for duplicate measurements of 15 proteins in 2322 participants from a community-based cohort, a plasma control, and recombinant protein controls using 2 custom planar microarrays with 6 (panel A) or 9 (panel B) capture antibodies printed in each well. We selected constituent analytes in each panel based on endogenous concentrations and assay availability. Protocols were standardized for sample processing, storage, and freeze-thaw exposures. We analyzed data for effects of deviations from processing protocols, precision, and bias. RESULTS: Measurements were within reportable ranges for each of the assays; however, concentrations for 7 of the 15 proteins were not centered on the dose-response curves. An additional freeze-thaw cycle and erroneous sample dilution for a subset of samples produced significantly different results. Measurements with large differences between duplicates were seen to cluster by analyte, plate, and participant. Conventional univariate quality control algorithms rejected many plates. Plate-specific medians of cohort and plasma control data significantly covaried, an observation important for development of alternative quality control algorithms. CONCLUSIONS: Multiplex measurements present difficult challenges that require further analytical and statistical developments.


Assuntos
Proteínas/química , Controle de Qualidade , Estudos de Coortes , Humanos
13.
Adv Clin Chem ; 46: 295-317, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19004193

RESUMO

Elevated levels of low-density lipoprotein (LDL) cholesterol are a major risk factor for coronary heart disease. However, a significant number of coronary events occur in individuals with "normal" serum LDL cholesterol levels. It has been proposed that coronary heart disease (CHD) risk stratification may be improved by evaluating LDL particle size and number and lipoprotein (a) [Lp(a)] levels in addition to LDL-associated cholesterol levels. This chapter includes a brief review of lipoprotein biology and presents an overview of the association between novel lipoprotein markers and CHD risk. We also discuss methodologies currently available for atherogenic lipid subprofiling.


Assuntos
Aterosclerose/etiologia , LDL-Colesterol/sangue , Doença das Coronárias/etiologia , Animais , Apolipoproteínas B/sangue , LDL-Colesterol/química , Eletroforese , Humanos , Lipoproteína(a)/sangue , Lipoproteínas/química , Lipoproteínas/classificação , Lipoproteínas/fisiologia , Espectroscopia de Ressonância Magnética , Tamanho da Partícula , Ultracentrifugação
14.
BMC Genet ; 8: 59, 2007 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-17760997

RESUMO

BACKGROUND: With the advent of "omics" (e.g. genomics, transcriptomics, proteomics and phenomics), studies can produce enormous amounts of data. Managing this diverse data and integrating with other biological data are major challenges for the bioinformatics community. Comprehensive new tools are needed to store, integrate and analyze the data efficiently. DESCRIPTION: The PhenoGen Informatics website http://phenogen.uchsc.edu is a comprehensive toolbox for storing, analyzing and integrating microarray data and related genotype and phenotype data. The site is particularly suited for combining QTL and microarray data to search for "candidate" genes contributing to complex traits. In addition, the site allows, if desired by the investigators, sharing of the data. Investigators can conduct "in-silico" microarray experiments using their own and/or "shared" data. CONCLUSION: The PhenoGen website provides access to tools that can be used for high-throughput data storage, analyses and interpretation of the results. Some of the advantages of the architecture of the website are that, in the future, the present set of tools can be adapted for the analyses of any type of high-throughput "omics" data, and that access to new tools, available in the public domain or developed at PhenoGen, can be easily provided.


Assuntos
Sistemas de Gerenciamento de Base de Dados , Bases de Dados Genéticas , Genômica , Internet , Perfilação da Expressão Gênica , Locos de Características Quantitativas
15.
Hypertension ; 50(4): 708-14, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17785630

RESUMO

Resistin, a recently discovered proinflammatory cytokine, has been variably associated with insulin resistance, inflammation, and renal dysfunction. We investigated the association of plasma resistin with estimated glomerular filtration rate and albuminuria in 1575 hypertensive adults without known coronary heart disease or stroke (857 blacks and 718 non-Hispanic whites). Resistin was measured by a solid phase sandwich immunoassay, estimated glomerular filtration rate was estimated from serum creatinine, and albuminuria was expressed as urine albumin:creatinine ratio. After adjustment for coronary heart disease risk factors (age, sex, body mass index, smoking history, systolic blood pressure, diabetes, and total and high-density lipoprotein cholesterol) and use of renin-angiotensin blockers and statins, higher plasma resistin levels were associated with lower estimated glomerular filtration rate in both ethnic groups (each P<0.0001); the association remained significant after further adjustment for a marker of insulin resistance (homeostasis model assessment for insulin resistance) and a marker of inflammation (plasma C-reactive protein) and was seen in subjects with and without diabetes (each P<0.0001) in both ethnic groups. Higher plasma resistin levels were associated with a higher urine albumin:creatinine ratio in black subjects with diabetes (P<0.0001) and non-Hispanic white subjects with diabetes (P=0.032), independent of coronary heart disease risk factors, hypertension medication use, and statin use; the association remained significant after additional adjustment for homeostasis model assessment for insulin resistance and C-reactive protein. In adults with hypertension, higher circulating resistin levels were associated with a lower estimated glomerular filtration rate and with increased urine albumin:creatinine ratio in the presence of concomitant diabetes. This association was independent of coronary heart disease risk factors and markers of insulin resistance and inflammation.


Assuntos
Albuminúria/sangue , Taxa de Filtração Glomerular/fisiologia , Hipertensão/sangue , Resistina/sangue , Idoso , Biomarcadores/sangue , População Negra , Creatinina/sangue , Estudos Transversais , Diabetes Mellitus/sangue , Diabetes Mellitus/metabolismo , Diabetes Mellitus/fisiopatologia , Feminino , Humanos , Inflamação/metabolismo , Inflamação/fisiopatologia , Resistência à Insulina/fisiologia , Modelos Lineares , Masculino , Pessoa de Meia-Idade , População Branca
16.
Anticancer Res ; 26(2A): 1039-48, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16619504

RESUMO

Higher soy food intake has been hypothesized to be a major factor explaining the decreased breast cancer risk in Asian countries, compared to those regions of the world consuming predominantly Western-style diets. Consumption of soy isoflavones, particularly genistein, has received considerable attention as the soy component largely responsible for the protective effects hypothesized to result from soy food consumption. However, the impact of adult consumption of soy foods on breast cancer risk in pre-menopausal and menopausal women is not consistent. There are recent epidemiological reports that consumption of soy foods can most effectively reduce breast cancer risk when consumed early in life during the pre-pubertal or adolescent periods. The aim of the present study was to evaluate the effects of physiologically-relevant levels of genistein (0.5 microM and 1 microM), concentrations achievable in the plasma following soy food consumption, on proliferation and expression of select genes in the human breast epithelial cell model. Treatment of the non-neoplastic, immortalized human breast epithelial MCF-10F cells with these low concentrations of genistein was associated with decreased cell proliferation, down-regulation of the protooncogene MET, up-regulation of the breast tumor suppressor gene EGR-1, and up-regulation of the immediate-early response genes FOS and JUN. In addition, genistein treatment was associated with a significant increase in Egr-1 binding to the transcription factor Sp1. Taken together, these genistein-induced changes in gene expressions provide insights into potential mechanisms by which this isoflavone may protect human breast cells against neoplastic transformation.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Proteína 1 de Resposta de Crescimento Precoce/biossíntese , Genisteína/farmacologia , Proteínas Proto-Oncogênicas/biossíntese , Receptores de Fatores de Crescimento/biossíntese , Antineoplásicos/farmacologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proteína 1 de Resposta de Crescimento Precoce/genética , Células Epiteliais/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Genes fos/efeitos dos fármacos , Genes jun/efeitos dos fármacos , Humanos , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas c-fos/biossíntese , Proteínas Proto-Oncogênicas c-fos/genética , Proteínas Proto-Oncogênicas c-jun/biossíntese , Proteínas Proto-Oncogênicas c-jun/genética , Proteínas Proto-Oncogênicas c-met , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Receptores de Fatores de Crescimento/genética , Regulação para Cima/efeitos dos fármacos
17.
Carcinogenesis ; 27(2): 298-306, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16113053

RESUMO

Triterpenoid B-group soyasaponins have been found to induce macroautophagy in human colon cancer cells at concentrations obtainable through consumption of legume foodstuffs. In the present studies the mechanism(s) for this autophagy-inducing action of soyasaponins was evaluated by measuring changes in signal transduction pathways associated with autophagy. Specifically, inhibition of the Akt signaling pathway and enhanced activity of ERK1/2 have previously been implicated in controlling induction of macroautophagy in mammalian cancer cells. Here we show that these pathways are also involved in B-group soyasaponin-induced macroautophagy, as changes in enzyme activities preceded significant increases in autophagic activity. The autophagic capacity of HCT-15 cells was significantly increased by 6 h post-saponin exposure, which led us to measure alterations in signaling events that preceded this time point. We determined that exposure to B-group soyasaponins suppressed Akt activity maximally by 50%, which was associated with a reduction in the activating phosphorylation of the Akt-serine473 residue. In addition, ERK1/2 activity was significantly increased by 60%, and was determined to be necessary for B-group soyasaponin-induced autophagy. The raf-1 kinase has been identified as a potential point of cross-talk between the Akt and ERK1/2 signaling cascades. Following B-group soyasaponin treatment activity of raf-1 was significantly increased by a maximal 200%, suggesting that this enzyme in part modulates the enhanced ERK1/2 activity. These results provide new insights into the signaling events that control induction of autophagy by B-group soyasaponins in human colon cancer cells and suggest that soyasaponins warrant further study as potential colon cancer chemopreventive agents.


Assuntos
Autofagia , Neoplasias do Colo/patologia , Proteínas Proto-Oncogênicas c-akt/fisiologia , Saponinas/farmacologia , Fabaceae/química , Humanos , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Transdução de Sinais , Células Tumorais Cultivadas
18.
Carcinogenesis ; 26(1): 159-67, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15471899

RESUMO

The impact of triterpenoid saponins isolated from soybeans on suppression of colon cancer cell proliferation was evaluated. Experiments were conducted to determine the effects of a purified soybean B-group saponin extract on cell proliferation, cell-cycle distribution and programmed cell death in cultures of human HCT-15 colon adenocarcinoma cells. Treatment of cells with the soyasaponins at concentrations of 25-500 p.p.m. significantly reduced viable cell numbers after 24 and 48 h of exposure. Treatment of cells with 25 and 100 p.p.m. of saponins also resulted in a transient accumulation of cells in the S-phase of the cell cycle that was associated with a significant reduction of cyclin-dependant kinase-2 (CDK-2) activity. More striking was that, when examined by transmission electron microscopy, soyasaponin-treated cells exhibited an approximately 4.5-fold increase in cell morphologies characteristic of Type II non-apoptotic programmed cell death (PCD) including numerous autophagic vacuoles, changes that collectively suggest autophagic cell death. In addition, the protein levels of microtubule-associated protein light chain 3 (LC-3), a specific marker of macroautophagy, increased substantially following soyasaponin treatment. Taken together these results thus indicate that soybean saponins, at physiologically relevant doses, can suppress HCT-15 colon cancer cell proliferation through S-phase cell-cycle delay, and can induce macroautophagy, the hallmark of Type II PCD. These findings suggest that B-group soyasaponins may be another colon-cancer suppressive component of soy that warrants further examination as a potential chemopreventive phytochemical.


Assuntos
Adenocarcinoma/patologia , Autofagia/efeitos dos fármacos , Neoplasias do Colo/patologia , Saponinas/farmacologia , Proteínas de Soja/farmacologia , Adenocarcinoma/ultraestrutura , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Neoplasias do Colo/ultraestrutura , Relação Dose-Resposta a Droga , Humanos , Immunoblotting , Imunoprecipitação , Microscopia Eletrônica de Transmissão , Glycine max/química
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