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1.
Article in English | MEDLINE | ID: mdl-38765318

ABSTRACT

Background: Colorectal cancer is a common cause of screening preventable death in Chinese immigrants, but colorectal cancer screening rates remain low in this population. This study evaluated factors associated with colorectal cancer screening behaviors in Chinese Americans living in New York City. Methods: Participants were foreign-born Chinese Americans, aged 50 years or older, who completed internet surveys between November 2020 and May 2021 regarding their colorectal cancer screening behaviors. Data were collected on demographics, health care utilization, participants' levels of health literacy, English proficiency, colorectal cancer perceptions and current colorectal cancer screening behaviors. Bivariate analyses using chi-square or t-tests were performed to examine associations between colorectal cancer screening behaviors and participant characteristics. Results: 103 participants were surveyed with a mean age of 71.3 years. Most participants experienced high rates of socioeconomic disadvantage (i.e., less than a high school education, annual household income <$20,000, limited health literacy, and poor English proficiency). 92% were ever screened, 81% were up-to-date on screening, and 85% expressed intention to screen in the future. Almost all participants had a primary care provider and a language concordant provider. Individuals who intended to screen were more fearful of developing colorectal cancer (3.2 vs 2.8, p=0.02) and perceived a colorectal cancer diagnosis with greater severity (3.0 vs 2.7, p=0.07) than those without intention to screen. Conclusions: In our sample, Chinese immigrants were adversely impacted by multiple social determinants of health but reported high colorectal cancer screening rates. Community-based outreach is critical to ensuring cancer-screening engagement in medically vulnerable populations.

2.
Child Maltreat ; 27(4): 605-614, 2022 11.
Article in English | MEDLINE | ID: mdl-33896222

ABSTRACT

Adverse and advantageous childhood experiences (ACEs and counter-ACEs) during adolescence are understudied. This study examined how childhood experiences affect youth tobacco/alcohol use. Participants included 489 U.S. adolescents (baseline 10-13 years; 51% female) from the first five waves of the Flourishing Families Project. Results of the cross-lagged model showed ACEs were predictive of early tobacco use only. Counter-ACEs in wave two and wave three predicted, respectively, decreased tobacco and decreased alcohol use in the following wave. Counter-ACEs were also correlated with reduced alcohol and tobacco use in later waves. These findings indicate the salience of counter-ACEs over ACEs in persistent and late adolescent substance use, though ACEs may be important to consider to prevent very early initiation of tobacco.


Subject(s)
Adverse Childhood Experiences , Substance-Related Disorders , Adolescent , Alcohol Drinking , Female , Humans , Male , Substance-Related Disorders/epidemiology
3.
Physiother Can ; 72(2): 149-157, 2020.
Article in English | MEDLINE | ID: mdl-32494099

ABSTRACT

Purpose: Panoramic ultrasound imaging (pUSI) is an extended field of view (FOV) imaging technique that enables visualization of larger muscles; however, it is not available in all ultrasound systems. Using an acoustic standoff pad that is compatible with any ultrasound system may be an alternative method to increase FOV, but it has not been used to evaluate limb muscles. The purpose of this study was to evaluate the reliability and feasibility of using pUSI and an acoustic standoff pad to measure the limb muscle cross-sectional area (mCSA). Method: A cross-sectional study was conducted. Using pUSI and an acoustic standoff pad, we obtained B-mode ultrasound images of the rectus femoris, biceps brachii, and lateral gastrocnemius muscles of 26 healthy participants on two occasions 7-10 days apart. The agreement between the two methods was determined using intra-class correlation coefficients (ICCs) and Bland-Altman plots. Test-retest reliability was assessed using ICCs and standard error of measurement (SEM). The feasibility of acquiring and analyzing the images was evaluated using a Likert scale. Results: The acoustic standoff pad and pUSI demonstrated strong agreement (ICC[3,3] > 0.85); however, the mCSAs were different (p < 0.05). Test-retest reliability for each technique was high for all muscles (ICC[3,3] > 0.85; SEM = 0.6-1.5 cm2). Image acquisition was highly feasible, but there were some limitations in analyzing the images. Conclusions: pUSI and an acoustic standoff pad are two reliable techniques for measuring mCSA, but the measurements are not directly comparable. Future studies should evaluate the accuracy of the acoustic standoff pad compared with gold-standard methods.


Objectif : l'imagerie panoramique (IP) est une technique à champ étendu (CÉ) qui permet de visualiser les grands muscles, mais qui n'est pas offerte dans tous les systèmes d'échographie. Un panneau acoustique autonome compatible avec les autres systémes d'échographie peut être utilisé pour accroître l'étendue du champ, mais il n'a pas été utilisé pour évaluer les muscles des membres. La présente étude visait à évaluer la fiabilité de l'IP et la faisabilité de l'utiliser comme panneau acoustique autonome pour mesurer la surface transversale du muscle (STM) du membre. Méthodologie : les chercheurs ont réalisé une étude transversale. Ils ont obtenu des images d'échographie en mode B du muscle droit antérieur de la cuisse, du biceps brachial et des muscles gastrocnémiens latéraux à l'aide de l'IP et d'un panneau acoustique autonome chez 26 sujets en santé à deux reprises (à sept à dix jours d'écart). Ils ont établi la concordance entre les deux méthodes à l'aide des coefficients de corrélation intraclasse (CCI) et des courbes de Bland-Altman. Ils ont évalué la fiabilité test-retest à l'aide des CCI et de l'écart-type de mesure standard (ÉTM). Ils ont évalué la faisabilité d'acquérir et d'analyser les images à l'aide de l'échelle de Likert. Résultats : Le panneau acoustique autonome et l'IP présentaient une forte concordance (CCI[3,3] > 0,85), mais les STM étaient différentes (p < 0,05). La fiabilité test-retest de chaque technique était élevée pour tous les muscles (CCI[3,3] > 0,85; ÉTM = 0,6 à 1,5 cm2). Il était hautement faisable d'acquérir les images, mais il y avait certaines limites à les analyser. Conclusions : Un IP et un panneau acoustique autonome sont deux techniques fiables pour mesurer la STM, mais les mesures ne sont pas directement comparables. De futures études devront évaluer la précision du panneau acoustique autonome par rapport aux méthodes de référence.

4.
Heliyon ; 6(5): e03927, 2020 May.
Article in English | MEDLINE | ID: mdl-32420492

ABSTRACT

Existing literature demonstrates a strong relationship between childhood experiences and adult health outcomes. The Differential Susceptibility to Environment Theory suggests that there are several factors, including personality, that affect a child's sensitivity to adverse and advantageous experiences. A sample of 246 adults (ages 19-57) were asked questions about extroverted personality characteristics, adverse and advantageous childhood experiences (ACEs and counter-ACEs), and several indicators of adult health, including executive functioning, perceived stress levels, depression, and past smoking habits. The sample was then stratified based on level of extroversion scores with the top quartile being labeled as "extroverts", the bottom quartile as "introverts", and those in between as "ambiverts". Regression analyses were then used to assess the relationship between childhood experiences and each adult health outcome. The results of the study showed that the relationship between childhood experiences and adult health was generally stronger among extroverted individuals. These results suggest that extroverts may be more sensitive to environmental influences in childhood as compared to introverts and ambiverts. More research is needed to understand the neurobiological mechanisms that increase environmental sensitivity among extroverts.

5.
Child Abuse Negl ; 96: 104089, 2019 10.
Article in English | MEDLINE | ID: mdl-31362100

ABSTRACT

BACKGROUND: Numerous studies over the past two decades have found a link between adverse childhood experiences (ACEs) and worse adult health outcomes. Less well understood is how advantageous childhood experiences (counter-ACEs) may lead to better adult health, especially in the presence of adversity. OBJECTIVE: To examine how counter-ACEs and ACEs affect adult physical and mental health using Resiliency Theory as the theoretical framework. PARTICIPANTS AND SETTING: Participants were Amazon mTurk users ages 19-57 years (N = 246; 42% female) who completed an online survey. METHODS: We conducted a series of regression analyses to examine how counter-ACEs and ACEs predicted adult health. RESULTS: Corresponding to the Compensatory Model of Resiliency Theory, higher counter-ACEs scores were associated with improved adult health and that counter-ACEs neutralized the negative impact of ACEs on adult health. Contrary to the Protective Factors Model, there was a stronger relationship between ACEs and worse adult health among those with above average counter-ACEs scores compared to those with below average counter-ACEs scores. Consistent with the Challenge Model, counter-ACEs had a reduced positive effect on adult health among those with four or more ACEs compared to those with fewer than four ACEs. CONCLUSIONS: Overall, the findings suggest that counter-ACEs protect against poor adult health and lead to better adult wellness. When ACEs scores are moderate, counter-ACEs largely neutralize the negative effects of ACEs on adult health. Ultimately, the results demonstrate that a public health approach to promoting positive childhood experiences may promote better lifelong health.


Subject(s)
Adverse Childhood Experiences , Health Status , Mental Health , Adult , Female , Humans , Male , Middle Aged , Protective Factors , Surveys and Questionnaires , Young Adult
6.
Health Psychol Open ; 6(1): 2055102919848572, 2019.
Article in English | MEDLINE | ID: mdl-31205734

ABSTRACT

The purpose of this study was to explore the physical, social, and mental health correlates of executive functioning in adults. Our sample consisted of 250 adults aged 18-55 years who participated in a survey. Participants reported on their physical health behaviors, family closeness, and mental health. Using hierarchical linear regression, the final model explained 41 percent of executive functioning in adults. Dispositional forgiveness of situations, stress, and living in a single-family home were the only significant correlates of executive functioning. These results are useful for better understanding possible mechanisms through which to improve executive functioning in adults.

7.
JMIR Mhealth Uhealth ; 7(3): e10794, 2019 03 22.
Article in English | MEDLINE | ID: mdl-30900992

ABSTRACT

BACKGROUND: Mindfulness meditation has become increasingly popular over the last few years, due in part to the increase in mobile apps incorporating the practice. Although studies have demonstrated the potential of mindfulness meditation to positively impact health, little has been uncovered about what predicts engagement in mindfulness meditation. Understanding the predictors of mindfulness meditation may help practitioners and phone app developers improve intervention strategies and app experience. OBJECTIVE: The purpose of this study was to use the Theory of Planned Behavior and Temporal Self-Regulation Theory to determine factors predicting mindfulness meditation mobile app use. METHODS: The sample consisted of 85 undergraduate students with no prior mindfulness meditation experience. During their first laboratory visit, participants completed tasks to measure their executive functioning and a survey to measure Theory of Planned Behavior constructs about mindfulness meditation. Over the following 2 weeks, participants logged the days and minutes that they practiced mindfulness meditation using a phone app. Hierarchical regression modeling was used to analyze the data. RESULTS: After controlling for demographic factors, participant subjective norms (beta=14.51, P=.001) and intentions (beta=36.12, P=.001) were predictive of the number of minutes practicing mindfulness. Participant executive functioning did not predict mindfulness meditation practice, nor did it moderate the link between intentions and mindfulness meditation practice. Participant attitudes (beta=0.44, P<.001) and perceived control (beta=0.42, P=.002) were positively associated with intentions to practice mindfulness. CONCLUSIONS: These results suggest that among college student populations, the Theory of Planned Behavior may be useful in predicting the use of mindfulness meditation phone apps. However, participant executive functioning was not a predictor or moderator of mindfulness practice, and Temporal Self-Regulation Theory may be less useful for explaining mindfulness meditation behaviors using phone apps over a short period of time among college students. The results have implications for public health professionals, suggesting that a focus on subjective norms and intentions may promote mindfulness meditation practice using phone apps.


Subject(s)
Meditation/methods , Mindfulness/instrumentation , Mobile Applications/standards , Social Theory , Cohort Studies , Female , Humans , Male , Mindfulness/methods , Mobile Applications/statistics & numerical data , Students/psychology , Students/statistics & numerical data , Surveys and Questionnaires , Utah , Young Adult
8.
Neurobiol Dis ; 76: 37-45, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25644311

ABSTRACT

MECP2 mutations cause the X-linked neurodevelopmental disorder Rett Syndrome (RTT) by consistently altering the protein encoded by the MECP2e1 alternative transcript. While mutations that simultaneously affect both MECP2e1 and MECP2e2 isoforms have been widely studied, the consequence of MECP2e1 deficiency on human neurons remains unknown. Here we report the first isoform-specific patient induced pluripotent stem cell (iPSC) model of RTT. RTTe1 patient iPS cell-derived neurons retain an inactive X-chromosome and express only the mutant allele. Single-cell mRNA analysis demonstrated they have a molecular signature of cortical neurons. Mutant neurons exhibited a decrease in soma size, reduced dendritic complexity and decreased cell capacitance, consistent with impaired neuronal maturation. The soma size phenotype was rescued cell-autonomously by MECP2e1 transduction in a level-dependent manner but not by MECP2e2 gene transfer. Importantly, MECP2e1 mutant neurons showed a dysfunction in action potential generation, voltage-gated Na(+) currents, and miniature excitatory synaptic current frequency and amplitude. We conclude that MECP2e1 mutation affects soma size, information encoding properties and synaptic connectivity in human neurons that are defective in RTT.


Subject(s)
Induced Pluripotent Stem Cells/pathology , Induced Pluripotent Stem Cells/physiology , Methyl-CpG-Binding Protein 2/genetics , Neurons/pathology , Neurons/physiology , Rett Syndrome/genetics , Action Potentials , Humans , Mutation , Neurons/metabolism , Protein Isoforms , Rett Syndrome/pathology , Rett Syndrome/physiopathology
9.
PLoS One ; 9(4): e91742, 2014.
Article in English | MEDLINE | ID: mdl-24699272

ABSTRACT

Mutations in MECP2 are responsible for the majority of Rett syndrome cases. MECP2 is a regulator of transcription, and has two isoforms, MECP2_e1 and MECP2_e2. There is accumulating evidence that MECP2_e1 is the etiologically relevant variant for Rett. In this study we aim to detect genes that are differentially transcribed in neuronal cells over-expressing either of these two MECP2 isoforms. The human neuroblastoma cell line SK-N-SH was stably infected by lentiviral vectors over-expressing MECP2_e1, MECP2_e2, or eGFP, and were then differentiated into neurons. The same lentiviral constructs were also used to infect mouse Mecp2 knockout (Mecp2(tm1.1Bird)) fibroblasts. RNA from these cells was used for microarray gene expression analysis. For the human neuronal cells, ∼ 800 genes showed >three-fold change in expression level with the MECP2_e1 construct, and ∼ 230 with MECP2_e2 (unpaired t-test, uncorrected p value <0.05). We used quantitative RT-PCR to verify microarray results for 41 of these genes. We found significant up-regulation of several genes resulting from over-expression of MECP2_e1 including SRPX2, NAV3, NPY1R, SYN3, and SEMA3D. DOCK8 was shown via microarray and qRT-PCR to be upregulated in both SK-N-SH cells and mouse fibroblasts. Both isoforms up-regulated GABRA2, KCNA1, FOXG1 and FOXP2. Down-regulation of expression in the presence of MECP2_e1 was seen with UNC5C and RPH3A. Understanding the biology of these differentially transcribed genes and their role in neurodevelopment may help us to understand the relative functions of the two MECP2 isoforms, and ultimately develop a better understanding of RTT etiology and determine the clinical relevance of isoform-specific mutations.


Subject(s)
Biomarkers/metabolism , Cell Differentiation , Fibroblasts/metabolism , Gene Expression Profiling , Methyl-CpG-Binding Protein 2/physiology , Neuroblastoma/genetics , Neurons/metabolism , Animals , Cells, Cultured , Fibroblasts/cytology , Humans , Mice , Mice, Knockout , Neuroblastoma/pathology , Neurons/cytology , Oligonucleotide Array Sequence Analysis , Protein Isoforms , RNA, Messenger/genetics , Real-Time Polymerase Chain Reaction , Reverse Transcriptase Polymerase Chain Reaction
10.
Comput Biol Chem ; 49: 23-35, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24583602

ABSTRACT

In this paper, we present a new statistical pattern recognition method for classifying cytotoxic cellular responses to toxic agents. The advantage of the proposed method is to quickly assess the toxicity level of an unclassified toxic agent on human health by bringing cytotoxic cellular responses with similar patterns (mode of action, MoOA) into the same class. The proposed method is a model-based hierarchical classification approach incorporating principal component analysis (PCA) and functional data analysis (FDA). The cytotoxic cell responses are represented by multi-concentration time-dependent cellular response profiles (TCRPs) which are dynamically recorded by using the xCELLigence real-time cell analysis high-throughput (RTCA HT) system. The classification results obtained using our algorithm show satisfactory discrimination and are validated using biological facts by examining common chemical mechanisms of actions with treatment on human hepatocellular carcinoma cells (HepG2).


Subject(s)
Antineoplastic Agents/classification , Antineoplastic Agents/pharmacology , Principal Component Analysis , Algorithms , Antineoplastic Agents/chemistry , Cell Proliferation/drug effects , Cluster Analysis , Hep G2 Cells , Humans , Time Factors
11.
Front Psychiatry ; 3: 24, 2012.
Article in English | MEDLINE | ID: mdl-22470355

ABSTRACT

Rett syndrome (RTT) is a neurodevelopmental disorder that affects girls due primarily to heterozygous mutations in the X-linked gene encoding methyl-CpG binding protein 2 (MECP2). Random X-chromosome inactivation (XCI) results in cellular mosaicism in which some cells express wild-type (WT) MECP2 while other cells express mutant MECP2. The generation of patient-specific human induced pluripotent stem cells (hiPSCs) facilitates the production of RTT-hiPSC-derived neurons in vitro to investigate disease mechanisms and identify novel drug treatments. The generation of RTT-hiPSCs has been reported by many laboratories, however, the XCI status of RTT-hiPSCs has been inconsistent. Some report RTT-hiPSCs retain the inactive X-chromosome (post-XCI) of the founder somatic cell allowing isogenic RTT-hiPSCs that express only the WT or mutant MECP2 allele to be isolated from the same patient. Post-XCI RTT-hiPSCs-derived neurons retain this allele-specific expression pattern of WT or mutant MECP2. Conversely, others report RTT-hiPSCs in which the inactive X-chromosome of the founder somatic cell reactivates (pre-XCI) upon reprogramming into RTT-hiPSCs. Pre-XCI RTT-hiPSC-derived neurons exhibit random XCI resulting in cellular mosaicism with respect to WT and mutant MECP2 expression. Here we review and attempt to interpret the inconsistencies in XCI status of RTT-hiPSCs generated to date by comparison to other pluripotent systems in vitro and in vivo and the methods used to analyze XCI. Finally, we discuss the relative strengths and weaknesses of post- and pre-XCI hiPSCs in the context of RTT, and other X-linked and autosomal disorders for translational medicine.

12.
Eur J Hum Genet ; 19(12): 1246-55, 2011 Dec.
Article in English | MEDLINE | ID: mdl-21750574

ABSTRACT

Rett syndrome (RTT) is a progressive neurologic disorder representing one of the most common causes of mental retardation in females. To date mutations in three genes have been associated with this condition. Classic RTT is caused by mutations in the MECP2 gene, whereas variants can be due to mutations in either MECP2 or FOXG1 or CDKL5. Mutations in CDKL5 have been identified both in females with the early onset seizure variant of RTT and in males with X-linked epileptic encephalopathy. CDKL5 is a kinase protein highly expressed in neurons, but its exact function inside the cell is unknown. To address this issue we established a human cellular model for CDKL5-related disease using the recently developed technology of induced pluripotent stem cells (iPSCs). iPSCs can be expanded indefinitely and differentiated in vitro into many different cell types, including neurons. These features make them the ideal tool to study disease mechanisms directly on the primarily affected neuronal cells. We derived iPSCs from fibroblasts of one female with p.Q347X and one male with p.T288I mutation, affected by early onset seizure variant and X-linked epileptic encephalopathy, respectively. We demonstrated that female CDKL5-mutated iPSCs maintain X-chromosome inactivation and clones express either the mutant CDKL5 allele or the wild-type allele that serve as an ideal experimental control. Array CGH indicates normal isogenic molecular karyotypes without detection of de novo CNVs in the CDKL5-mutated iPSCs. Furthermore, the iPS cells can be differentiated into neurons and are thus suitable to model disease pathogenesis in vitro.


Subject(s)
Induced Pluripotent Stem Cells/metabolism , Protein Serine-Threonine Kinases/genetics , Rett Syndrome/genetics , Cell Differentiation , Child , Child, Preschool , Female , Humans , Induced Pluripotent Stem Cells/cytology , Male , Mutation , Neurons/cytology , Neurons/metabolism , Protein Serine-Threonine Kinases/metabolism , Rett Syndrome/diagnosis , X Chromosome Inactivation
13.
Hum Mol Genet ; 20(11): 2103-15, 2011 Jun 01.
Article in English | MEDLINE | ID: mdl-21372149

ABSTRACT

Rett syndrome (RTT) is a neurodevelopmental autism spectrum disorder that affects girls due primarily to mutations in the gene encoding methyl-CpG binding protein 2 (MECP2). The majority of RTT patients carry missense and nonsense mutations leading to a hypomorphic MECP2, while null mutations leading to the complete absence of a functional protein are rare. MECP2 is an X-linked gene subject to random X-chromosome inactivation resulting in mosaic expression of mutant MECP2. The lack of human brain tissue motivates the need for alternative human cellular models to study RTT. Here we report the characterization of a MECP2 mutation in a classic female RTT patient involving rearrangements that remove exons 3 and 4 creating a functionally null mutation. To generate human neuron models of RTT, we isolated human induced pluripotent stem (hiPS) cells from RTT patient fibroblasts. RTT-hiPS cells retained the MECP2 mutation, are pluripotent and fully reprogrammed, and retained an inactive X-chromosome in a nonrandom pattern. Taking advantage of the latter characteristic, we obtained a pair of isogenic wild-type and mutant MECP2 expressing RTT-hiPS cell lines that retained this MECP2 expression pattern upon differentiation into neurons. Phenotypic analysis of mutant RTT-hiPS cell-derived neurons demonstrated a reduction in soma size compared with the isogenic control RTT-hiPS cell-derived neurons from the same RTT patient. Analysis of isogenic control and mutant hiPS cell-derived neurons represents a promising source for understanding the pathogenesis of RTT and the role of MECP2 in human neurons.


Subject(s)
Induced Pluripotent Stem Cells/metabolism , Methyl-CpG-Binding Protein 2/genetics , Neurons/pathology , Rett Syndrome/genetics , X Chromosome Inactivation , Brain/cytology , Brain/metabolism , Cell Differentiation , Cell Line , Chromosome Mapping , Chromosomes, Human, X/genetics , DNA Fingerprinting , Exons , Female , Gene Expression Regulation , Genes, X-Linked , Genotype , Humans , Immunohistochemistry , Karyotyping , Male , Methyl-CpG-Binding Protein 2/metabolism , Mutation , Neurons/cytology , Phenotype
14.
Nat Protoc ; 4(12): 1828-44, 2009.
Article in English | MEDLINE | ID: mdl-20010937

ABSTRACT

Generation of induced pluripotent stem (iPS) cells from patients has exciting applications for studying molecular mechanisms of diseases, screening drugs and ultimately for use in cell therapies. However, the low efficiency and heterogeneous nature of reprogramming is a major impediment to the generation of personalized iPS cell lines. We reported in Nature Methods (6, 370-376, 2009) the first selection system to enrich for reprogrammed human iPS cells. Using a lentiviral vector that specifically expresses the enhanced green fluorescence protein and puromycin resistance genes in pluripotent stem cells, it is now possible to mark and enrich for human iPS cell colonies expressing endogenous pluripotency markers. In this study, we describe a detailed protocol for the production of the pluripotent state-specific lentiviral vector and the selection system for the induction of healthy and disease-specific human iPS cells. Overall, preparation of the selection system takes 2 weeks, and the generation of human iPS cells takes approximately 2 months.


Subject(s)
Cell Culture Techniques , Genetic Vectors , Induced Pluripotent Stem Cells/cytology , Lentivirus/genetics , Animals , Biomarkers/metabolism , Drug Resistance/genetics , Fibroblasts/cytology , Fibroblasts/virology , Green Fluorescent Proteins/analysis , Green Fluorescent Proteins/metabolism , Humans , Induced Pluripotent Stem Cells/virology , Mice , Transfection/methods
15.
PLoS One ; 4(8): e6810, 2009 Aug 27.
Article in English | MEDLINE | ID: mdl-19710912

ABSTRACT

BACKGROUND: Rett Syndrome (RTT) is an Autism Spectrum Disorder and the leading cause of mental retardation in females. RTT is caused by mutations in the Methyl CpG-Binding Protein-2 (MECP2) gene and has no treatment. Our objective is to develop viral vectors for MECP2 gene transfer into Neural Stem Cells (NSC) and neurons suitable for gene therapy of Rett Syndrome. METHODOLOGY/PRINCIPAL FINDINGS: We generated self-inactivating (SIN) retroviral vectors with the ubiquitous EF1alpha promoter avoiding known silencer elements to escape stem-cell-specific viral silencing. High efficiency NSC infection resulted in long-term EGFP expression in transduced NSC and after differentiation into neurons. Infection with Myc-tagged MECP2-isoform-specific (E1 and E2) vectors directed MeCP2 to heterochromatin of transduced NSC and neurons. In contrast, vectors with an internal mouse Mecp2 promoter (MeP) directed restricted expression only in neurons and glia and not NSC, recapitulating the endogenous expression pattern required to avoid detrimental consequences of MECP2 ectopic expression. In differentiated NSC from adult heterozygous Mecp2(tm1.1Bird)+/- female mice, 48% of neurons expressed endogenous MeCP2 due to random inactivation of the X-linked Mecp2 gene. Retroviral MECP2 transduction with EF1alpha and MeP vectors rescued expression in 95-100% of neurons resulting in increased dendrite branching function in vitro. Insulated MECP2 isoform-specific lentiviral vectors show long-term expression in NSC and their differentiated neuronal progeny, and directly infect dissociated murine cortical neurons with high efficiency. CONCLUSIONS/SIGNIFICANCE: MeP vectors recapitulate the endogenous expression pattern of MeCP2 in neurons and glia. They have utility to study MeCP2 isoform-specific functions in vitro, and are effective gene therapy vectors for rescuing dendritic maturation of neurons in an ex vivo model of RTT.


Subject(s)
Gene Expression Regulation , Genetic Therapy , Genetic Vectors , Methyl-CpG-Binding Protein 2/genetics , Rett Syndrome/therapy , Animals , Female , Humans , Lentivirus/genetics , Mice , Promoter Regions, Genetic , Transduction, Genetic
16.
Nat Methods ; 6(5): 370-6, 2009 May.
Article in English | MEDLINE | ID: mdl-19404254

ABSTRACT

Induced pluripotent stem (iPS) cells may be of use in regenerative medicine. However, the low efficiency of reprogramming is a major impediment to the generation of patient-specific iPS cell lines. Here we report the first selection system for the isolation of human iPS cells. We developed the EOS (Early Transposon promoter and Oct-4 (Pou5f1) and Sox2 enhancers) lentiviral vector to specifically express in mouse and human embryonic stem cells but not in primary fibroblasts. The bicistronic EOS vector marked emerging mouse and human iPS cell colonies with EGFP, and we used puromycin selection to aid the isolation of iPS cell lines that expressed endogenous pluripotency markers. These lines differentiated into cell types from all three germ layers. Reporter expression was extinguished upon differentiation and therefore monitored the residual pluripotent cells that form teratomas. Finally, we used EOS selection to establish Rett syndrome-specific mouse and human iPS cell lines with known mutations in MECP2.


Subject(s)
Cell Dedifferentiation/genetics , Cell Separation/methods , Genes, Reporter/genetics , Genetic Vectors/genetics , Lentivirus/genetics , Pluripotent Stem Cells/cytology , Pluripotent Stem Cells/metabolism , Animals , Cell Differentiation/drug effects , DNA Transposable Elements/genetics , Embryo, Mammalian/cytology , Embryonic Stem Cells/cytology , Embryonic Stem Cells/metabolism , Enhancer Elements, Genetic/genetics , Fibroblasts/cytology , Fibroblasts/metabolism , Green Fluorescent Proteins/genetics , Green Fluorescent Proteins/metabolism , Humans , Methyl-CpG-Binding Protein 2/genetics , Mice , Mice, Inbred NOD , Mice, Mutant Strains , Mice, SCID , Promoter Regions, Genetic/genetics , Rett Syndrome/genetics , Rett Syndrome/pathology , Teratoma/pathology
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