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1.
Pharmacogenomics ; 24(5): 243-246, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37014361

RESUMO

On 8-9 November 2022, the European Society of Pharmacogenomics and Personalised Therapy organized its sixth biennial congress, in Belgrade, Serbia (congress website: www.sspt.rs). The congress aimed to address the current status and future perspectives of pharmacogenomics, share latest knowledge in the field of precision medicine and showcase the implementation of clinical applications in pharmacogenomics/pharmacogenetics. The 2 day congress consisted of 17 lectures given by key-opinion leaders and included a poster session plus discussions. The meeting was a great success by generating an informal environment and enabling the exchange of information between 162 participants from 16 different countries.


Assuntos
Farmacogenética , Medicina de Precisão , Humanos
2.
Sci Rep ; 9(1): 2677, 2019 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-30804413

RESUMO

Performance of astronaut pilots during space shuttle landing was degraded after a few weeks of microgravity exposure, and longer-term exposure has the potential to impact operator proficiency during critical landing and post-landing operations for exploration-class missions. Full-motion simulations of operationally-relevant tasks were utilized to assess the impact of long-duration spaceflight on operator proficiency in a group of 8 astronauts assigned to the International Space Station, as well as a battery of cognitive/sensorimotor tests to determine the underlying cause of any post-flight performance decrements. A ground control group (N = 12) and a sleep restriction cohort (N = 9) were also tested to control for non-spaceflight factors such as lack of practice between pre- and post-flight testing and fatigue. On the day of return after 6 months aboard the space station, astronauts exhibited significant deficits in manual dexterity, dual-tasking and motion perception, and a striking degradation in the ability to operate a vehicle. These deficits were not primarily due to fatigue; performance on the same tasks was unaffected after a 30-h period of sleep restriction. Astronauts experienced a general post-flight malaise in motor function and motion perception, and a lack of cognitive reserve apparent only when faced with dual tasks, which had recovered to baseline by four days after landing.


Assuntos
Astronautas/estatística & dados numéricos , Voo Espacial , Astronave , Ausência de Peso , Adulto , Astronautas/psicologia , Cognição/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Percepção de Movimento/fisiologia , Testes Psicológicos/estatística & dados numéricos , Desempenho Psicomotor/fisiologia , Sono/fisiologia , Fatores de Tempo
3.
Nat Med ; 25(3): 517-525, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30664780

RESUMO

The molecular alterations that occur in cells before cancer is manifest are largely uncharted. Lung carcinoma in situ (CIS) lesions are the pre-invasive precursor to squamous cell carcinoma. Although microscopically identical, their future is in equipoise, with half progressing to invasive cancer and half regressing or remaining static. The cellular basis of this clinical observation is unknown. Here, we profile the genomic, transcriptomic, and epigenomic landscape of CIS in a unique patient cohort with longitudinally monitored pre-invasive disease. Predictive modeling identifies which lesions will progress with remarkable accuracy. We identify progression-specific methylation changes on a background of widespread heterogeneity, alongside a strong chromosomal instability signature. We observed mutations and copy number changes characteristic of cancer and chart their emergence, offering a window into early carcinogenesis. We anticipate that this new understanding of cancer precursor biology will improve early detection, reduce overtreatment, and foster preventative therapies targeting early clonal events in lung cancer.


Assuntos
Carcinoma in Situ/genética , Carcinoma de Células Escamosas/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinogênese/genética , Instabilidade Cromossômica/genética , Estudos de Coortes , Variações do Número de Cópias de DNA , Metilação de DNA/genética , Progressão da Doença , Epigenômica , Feminino , Perfilação da Expressão Gênica , Genômica , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Mutação
4.
J Gerontol A Biol Sci Med Sci ; 74(1): 57-61, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-29718110

RESUMO

Background: Epigenetic clocks based on DNA methylation yield high correlations with chronological age in cross-sectional data. Due to a paucity of longitudinal data, it is not known how Δage (epigenetic age - chronological age) changes over time or if it remains constant from childhood to old age. Here, we investigate this using longitudinal DNA methylation data from five datasets, covering most of the human life course. Methods: Two measures of the epigenetic clock (Hannum and Horvath) are used to calculate Δage in the following cohorts: Avon Longitudinal Study of Parents and Children (ALSPAC) offspring (n = 986, total age-range 7-19 years, 2 waves), ALSPAC mothers (n = 982, 16-60 years, 2 waves), InCHIANTI (n = 460, 21-100 years, 2 waves), SATSA (n = 373, 48-99 years, 5 waves), Lothian Birth Cohort 1936 (n = 1,054, 70-76 years, 3 waves), and Lothian Birth Cohort 1921 (n = 476, 79-90 years, 3 waves). Linear mixed models were used to track longitudinal change in Δage within each cohort. Results: For both epigenetic age measures, Δage showed a declining trend in almost all of the cohorts. The correlation between Δage across waves ranged from 0.22 to 0.82 for Horvath and 0.25 to 0.71 for Hannum, with stronger associations in samples collected closer in time. Conclusions: Epigenetic age increases at a slower rate than chronological age across the life course, especially in the oldest population. Some of the effect is likely driven by survival bias, where healthy individuals are those maintained within a longitudinal study, although other factors like the age distribution of the underlying training population may also have influenced this trend.


Assuntos
Envelhecimento/genética , DNA/genética , Epigênese Genética , Longevidade/genética , Metilação de DNA , Humanos
5.
Nat Genet ; 50(11): 1542-1552, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30349119

RESUMO

Imprinting is the preferential expression of one parental allele over the other. It is controlled primarily through differential methylation of cytosine at CpG dinucleotides. Here we combine 285 methylomes and 11,617 transcriptomes from peripheral blood samples with parent-of-origin phased haplotypes, to produce a new map of imprinted methylation and gene expression patterns across the human genome. We demonstrate how imprinted methylation is a continuous rather than a binary characteristic. We describe at high resolution the parent-of-origin methylation pattern at the 15q11.2 Prader-Willi/Angelman syndrome locus, with nearly confluent stochastic paternal methylation punctuated by 'spikes' of maternal methylation. We find examples of polymorphic imprinted methylation unrelated (at VTRNA2-1 and PARD6G) or related (at CHRNE) to nearby SNP genotypes. We observe RNA isoform-specific imprinted expression patterns suggestive of a methylation-sensitive transcriptional elongation block. Finally, we gain new insights into parent-of-origin-specific effects on phenotypes at the DLK1/MEG3 and GNAS loci.


Assuntos
Metilação de DNA/genética , Genoma Humano , Impressão Genômica/fisiologia , Padrões de Herança/genética , Pais , Transcriptoma/genética , Síndrome de Angelman/genética , Estudos de Casos e Controles , Cromossomos Humanos Par 15 , Estudos de Coortes , Ilhas de CpG/genética , Feminino , Loci Gênicos , Humanos , Islândia , Masculino , Polimorfismo de Nucleotídeo Único , Síndrome de Prader-Willi/genética , Locos de Características Quantitativas/genética
6.
Epigenetics ; 13(9): 975-987, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30264654

RESUMO

Age-related changes in DNA methylation were observed in cross-sectional studies, but longitudinal evidence is still limited. Here, we aimed to characterize longitudinal age-related methylation patterns using 1011 blood samples collected from 385 Swedish twins (age at entry: mean 69 and standard deviation 9.7, 73 monozygotic and 96 dizygotic pairs) up to five times (mean 2.6) over 20 years (mean 8.7). We identified 1316 age-associated methylation sites (P<1.3×10-7) using a longitudinal epigenome-wide association study design. We measured how estimated cellular compositions changed with age and how much they confounded the age effect. We validated the results in two independent longitudinal cohorts, where 118 CpGs were replicated in Prospective Investigation of the Vasculature in Uppsala Seniors (PIVUS, 390 samples) (P<3.9×10-5), 594 in Lothian Birth Cohort (LBC, 3018 samples) (P<5.1×10-5) and 63 in both. Functional annotation of age-associated CpGs showed enrichment in CCCTC-binding factor (CTCF) and other transcription factor binding sites. We further investigated genetic influences on methylation and found no interaction between age and genetic effects in the 1316 age-associated CpGs. Moreover, in the same CpGs, methylation differences within twin pairs increased with 6.4% over 10 years, where monozygotic twins had smaller intra-pair differences than dizygotic twins. In conclusion, we show that age-related methylation changes persist in a longitudinal perspective, and are fairly stable across cohorts. The changes are under genetic influence, although this effect is independent of age. Moreover, methylation variability increase over time, especially in age-associated CpGs, indicating the increase of environmental contributions on DNA methylation with age.


Assuntos
Envelhecimento/genética , Metilação de DNA , Epigênese Genética , Idoso , Ilhas de CpG , Feminino , Estudo de Associação Genômica Ampla , Humanos , Masculino , Gêmeos Dizigóticos/genética , Gêmeos Monozigóticos/genética
7.
Bioinformatics ; 33(24): 3982-3984, 2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-28961746

RESUMO

SUMMARY: The Illumina Infinium HumanMethylationEPIC BeadChip is the new platform for high-throughput DNA methylation analysis, effectively doubling the coverage compared to the older 450 K array. Here we present a significantly updated and improved version of the Bioconductor package ChAMP, which can be used to analyze EPIC and 450k data. Many enhanced functionalities have been added, including correction for cell-type heterogeneity, network analysis and a series of interactive graphical user interfaces. AVAILABILITY AND IMPLEMENTATION: ChAMP is a BioC package available from https://bioconductor.org/packages/release/bioc/html/ChAMP.html. CONTACT: a.teschendorff@ucl.ac.uk or s.beck@ucl.ac.uk or a.feber@ucl.ac.uk. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Metilação de DNA , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Software
9.
Am J Trop Med Hyg ; 94(6): 1290-8, 2016 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-27044564

RESUMO

Autonomic dysfunction is common in Chagas disease and diabetes. Patients with either condition complicated by cardiac autonomic dysfunction face increased mortality, but no clinical predictors of autonomic dysfunction exist. Pupillary light reflexes (PLRs) may identify such patients early, allowing for intensified treatment. To evaluate the significance of PLRs, adults were recruited from the outpatient endocrine, cardiology, and surgical clinics at a Bolivian teaching hospital. After testing for Chagas disease and diabetes, participants completed conventional autonomic testing (CAT) evaluating their cardiovascular responses to Valsalva, deep breathing, and orthostatic changes. PLRs were measured using specially designed goggles, then CAT and PLRs were compared as measures of autonomic dysfunction. This study analyzed 163 adults, including 96 with Chagas disease, 35 patients with diabetes, and 32 controls. PLRs were not significantly different between Chagas disease patients and controls. Patients with diabetes had longer latency to onset of pupil constriction, slower maximum constriction velocities, and smaller orthostatic ratios than nonpatients with diabetes. PLRs correlated poorly with CAT results. A PLR-based clinical risk score demonstrated a 2.27-fold increased likelihood of diabetes complicated by autonomic dysfunction compared with the combination of blood tests, CAT, and PLRs (sensitivity 87.9%, specificity 61.3%). PLRs represent a promising tool for evaluating subclinical neuropathy in patients with diabetes without symptomatic autonomic dysfunction. Pupillometry does not have a role in the evaluation of Chagas disease patients.


Assuntos
Doenças do Sistema Nervoso Autônomo/diagnóstico , Doença de Chagas/complicações , Diabetes Mellitus/fisiopatologia , Retinopatia Diabética/diagnóstico , Reflexo Pupilar , Adulto , Doenças do Sistema Nervoso Autônomo/patologia , Doenças do Sistema Nervoso Autônomo/fisiopatologia , Bolívia/epidemiologia , Doença de Chagas/epidemiologia , Doença de Chagas/fisiopatologia , Retinopatia Diabética/epidemiologia , Retinopatia Diabética/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
10.
Nat Commun ; 7: 10458, 2016 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-26822956

RESUMO

Non-CG methylation is an unexplored epigenetic hallmark of pluripotent stem cells. Here we report that a reduction in non-CG methylation is associated with impaired differentiation capacity into endodermal lineages. Genome-wide analysis of 2,670 non-CG sites in a discovery cohort of 25 phenotyped human induced pluripotent stem cell (hiPSC) lines revealed unidirectional loss (Δß=13%, P<7.4 × 10(-4)) of non-CG methylation that correctly identifies endodermal differentiation capacity in 23 out of 25 (92%) hiPSC lines. Translation into a simplified assay of only nine non-CG sites maintains predictive power in the discovery cohort (Δß=23%, P<9.1 × 10(-6)) and correctly identifies endodermal differentiation capacity in nine out of ten pluripotent stem cell lines in an independent replication cohort consisting of hiPSCs reprogrammed from different cell types and different delivery systems, as well as human embryonic stem cell (hESC) lines. This finding infers non-CG methylation at these sites as a biomarker when assessing endodermal differentiation capacity as a readout.


Assuntos
Diferenciação Celular , Metilação de DNA , Endoderma/citologia , Células-Tronco Pluripotentes Induzidas/citologia , Biomarcadores/metabolismo , Estudos de Coortes , Endoderma/metabolismo , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo
11.
Clin Cancer Res ; 22(1): 250-8, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-26169971

RESUMO

PURPOSE: Small intestinal neuroendocrine tumors (SINET) are the commonest malignancy of the small intestine; however, underlying pathogenic mechanisms remain poorly characterized. Whole-genome and -exome sequencing has demonstrated that SINETs are mutationally quiet, with the most frequent known mutation in the cyclin-dependent kinase inhibitor 1B gene (CDKN1B) occurring in only ∼8% of tumors, suggesting that alternative mechanisms may drive tumorigenesis. The aim of this study is to perform genome-wide molecular profiling of SINETs in order to identify pathogenic drivers based on molecular profiling. This study represents the largest unbiased integrated genomic, epigenomic, and transcriptomic analysis undertaken in this tumor type. EXPERIMENTAL DESIGN: Here, we present data from integrated molecular analysis of SINETs (n = 97), including whole-exome or targeted CDKN1B sequencing (n = 29), HumanMethylation450 BeadChip (Illumina) array profiling (n = 69), methylated DNA immunoprecipitation sequencing (n = 16), copy-number variance analysis (n = 47), and Whole-Genome DASL (Illumina) expression array profiling (n = 43). RESULTS: Based on molecular profiling, SINETs can be classified into three groups, which demonstrate significantly different progression-free survival after resection of primary tumor (not reached at 10 years vs. 56 months vs. 21 months, P = 0.04). Epimutations were found at a recurrence rate of up to 85%, and 21 epigenetically dysregulated genes were identified, including CDX1 (86%), CELSR3 (84%), FBP1 (84%), and GIPR (74%). CONCLUSIONS: This is the first comprehensive integrated molecular analysis of SINETs. We have demonstrated that these tumors are highly epigenetically dysregulated. Furthermore, we have identified novel molecular subtypes with significant impact on progression-free survival.


Assuntos
Neoplasias Intestinais/genética , Neoplasias Intestinais/mortalidade , Intestino Delgado/metabolismo , Tumores Neuroendócrinos/genética , Tumores Neuroendócrinos/mortalidade , Adulto , Idoso , Cromossomos Humanos Par 18 , Análise por Conglomerados , Biologia Computacional/métodos , Inibidor de Quinase Dependente de Ciclina p27/genética , Variações do Número de Cópias de DNA , Metilação de DNA , Análise Mutacional de DNA , Epigênese Genética , Exoma , Feminino , Perfilação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Neoplasias Intestinais/diagnóstico , Intestino Delgado/patologia , Masculino , Pessoa de Meia-Idade , Mutação , Metástase Neoplásica , Estadiamento de Neoplasias , Tumores Neuroendócrinos/diagnóstico , Prognóstico , Reprodutibilidade dos Testes
12.
ABNF J ; 27(3): 64-66, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-29443469

RESUMO

Critical thinking is essential in the practice of the nurse generalist, today. Nursing faculty is frequently trying to identify teaching strategies in promoting critical thinking and engaging students in active learning. To close the gap between critical thinking and student success, a school in the south east United States implemented the use of the 'think like a nurse initiative" for incoming junior nursing students. Faculty collaborated to adopt the fundamental and essential nursing concepts for nursing students to support thinking like a nurse.


Assuntos
Atitude do Pessoal de Saúde , Bacharelado em Enfermagem/métodos , Processo de Enfermagem , Recursos Humanos de Enfermagem/psicologia , Estudantes de Enfermagem/psicologia , Pensamento , Adulto , Currículo , Docentes de Enfermagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , North Carolina , Pesquisa em Educação em Enfermagem , Pesquisa Metodológica em Enfermagem , Adulto Jovem
13.
Front Syst Neurosci ; 9: 88, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26106308

RESUMO

Performance on a visuomotor task in the presence of novel vestibular stimulation was assessed in nine healthy subjects. Four subjects had previously been adapted to 120 min exposure to noisy Galvanic vestibular stimulation (GVS) over 12 weekly sessions of 10 min; the remaining five subjects had never experienced GVS. Subjects were seated in a flight simulator and asked to null the roll motion of a visual bar presented on a screen using a joystick. Both the visual bar and the simulator cabin were moving in roll with a pseudorandom (sum of sines) waveform that were uncorrelated. The cross correlation coefficient, which ranges from 1 (identical waveforms) to 0 (unrelated waveforms), was calculated for the ideal (perfect nulling of bar motion) and actual joystick input waveform for each subject. The cross correlation coefficient for the GVS-adapted group (0.90 [SD 0.04]) was significantly higher (t[8] = 3.162; p = 0.013) than the control group (0.82 [SD 0.04]), suggesting that prior adaptation to GVS was associated with an enhanced ability to perform the visuomotor task in the presence of novel vestibular noise.

15.
Genome Med ; 7(1): 11, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25763109

RESUMO

BACKGROUND: Wilms tumours (WTs) are characterised by several hallmarks that suggest epimutations such as aberrant DNA methylation are involved in tumour progression: loss of imprinting at 11p15, lack of recurrent mutations and formation of nephrogenic rests (NRs), which are lesions of retained undifferentiated embryonic tissue that can give rise to WTs. METHODS: To identify such epimutations, we performed a comprehensive methylome analysis on 20 matched trios of micro-dissected WTs, NRs and surrounding normal kidneys (NKs) using Illumina Infinium HumanMethylation450 Bead Chips and functionally validated findings using RNA sequencing. RESULTS: Comparison of NRs with NK revealed prominent tissue biomarkers: 629 differentially methylated regions, of which 55% were hypermethylated and enriched for domains that are bivalent in embryonic stem cells and for genes expressed during development (P = 2.49 × 10(-5)). Comparison of WTs with NRs revealed two WT subgroups; group-2 WTs and NRs were epigenetically indistinguishable whereas group-1 WTs showed an increase in methylation variability, hypomethylation of renal development genes, hypermethylation and relative loss of expression of cell adhesion genes and known and potential new WT tumour suppressor genes (CASP8, H19, MIR195, RB1 and TSPAN32) and was strongly associated with bilateral disease (P = 0.032). Comparison of WTs and NRs to embryonic kidney highlighted the significance of polycomb target methylation in Wilms tumourigenesis. CONCLUSIONS: Methylation levels vary during cancer evolution. We have described biomarkers related to WT evolution from its precursor NRs which may be useful to differentiate between these tissues for patients with bilateral disease.

16.
Methods ; 72: 3-8, 2015 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-25233806

RESUMO

The Illumina HumanMethylation450 BeadChip has become a popular platform for interrogating DNA methylation in epigenome-wide association studies (EWAS) and related projects as well as resource efforts such as the International Cancer Genome Consortium (ICGC) and the International Human Epigenome Consortium (IHEC). This has resulted in an exponential increase of 450k data in recent years and triggered the development of numerous integrated analysis pipelines and stand-alone packages. This review will introduce and discuss the currently most popular pipelines and packages and is particularly aimed at new 450k users.


Assuntos
Ilhas de CpG , Metilação de DNA , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Epigenômica/métodos , Genoma , Genoma Humano , Humanos , Software
17.
Methods ; 72: 9-15, 2015 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-25175075

RESUMO

DNA methylation analysis has become an integral part of biomedical research. For high-throughput applications such as epigenome-wide association studies, the Infinium HumanMethylation450 (450K) BeadChip is currently the platform of choice. However, BeadChip processing relies on traditional bisulfite (BS) based protocols which cannot discriminate between 5-methylcytosine (5mC) and 5-hydroxymethylcytosine (5hmC). Here, we report the adaptation of the recently developed oxidative bisulfite (oxBS) chemistry to specifically detect both 5mC and 5hmC in a single workflow using 450K BeadChips, termed oxBS-450K. Supported by validation using mass spectrometry and pyrosequencing, we demonstrate reproducible (R(2)>0.99) detection of 5hmC in human brain tissue using the optimised oxBS-450K protocol described here.


Assuntos
Metilação de DNA , Epigenômica/métodos , Epigenômica/instrumentação , Humanos , Análise de Sequência com Séries de Oligonucleotídeos/instrumentação , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Reprodutibilidade dos Testes , Análise de Sequência de DNA/métodos
18.
PLoS One ; 9(11): e112131, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25409443

RESUMO

Healthy subjects (N = 10) were exposed to 10-min cumulative pseudorandom bilateral bipolar Galvanic vestibular stimulation (GVS) on a weekly basis for 12 weeks (120 min total exposure). During each trial subjects performed computerized dynamic posturography and eye movements were measured using digital video-oculography. Follow up tests were conducted 6 weeks and 6 months after the 12-week adaptation period. Postural performance was significantly impaired during GVS at first exposure, but recovered to baseline over a period of 7-8 weeks (70-80 min GVS exposure). This postural recovery was maintained 6 months after adaptation. In contrast, the roll vestibulo-ocular reflex response to GVS was not attenuated by repeated exposure. This suggests that GVS adaptation did not occur at the vestibular end-organs or involve changes in low-level (brainstem-mediated) vestibulo-ocular or vestibulo-spinal reflexes. Faced with unreliable vestibular input, the cerebellum reweighted sensory input to emphasize veridical extra-vestibular information, such as somatosensation, vision and visceral stretch receptors, to regain postural function. After a period of recovery subjects exhibited dual adaption and the ability to rapidly switch between the perturbed (GVS) and natural vestibular state for up to 6 months.


Assuntos
Adaptação Fisiológica , Estimulação Elétrica/métodos , Postura , Voo Espacial , Adulto , Astronautas , Medições dos Movimentos Oculares , Movimentos Oculares , Humanos , Masculino , Sensação , Testes de Função Vestibular
19.
Parkinsons Dis ; 2014: 606427, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25101189

RESUMO

A cardinal feature of freezing of gait (FOG) is high frequency (3-8 Hz) oscillation of the legs, and this study aimed to quantify the temporal pattern of lower-body motion prior to and during FOG. Acceleration data was obtained from sensors attached to the back, thighs, shanks, and feet in 14 Parkinson's disease patients performing timed-up-and-go tasks, and clinical assessment of FOG was performed by two experienced raters from video. A total of 23 isolated FOG events, defined as occurring at least 5 s after gait initiation and with no preceding FOG, were identified from the clinical ratings. The corresponding accelerometer records were analyzed within a 4 s window centered at the clinical onset of freezing. FOG-related high-frequency oscillation (an increase in power in the 3-8 Hz band >3 SD from baseline) followed a distal to proximal onset pattern, appearing at the feet, shanks, thighs, and then back over a period of 250 ms. Peak power tended to decrease as the focus of oscillation moved from feet to back. There was a consistent delay (mean 872 ms) between the onset of high frequency oscillation at the feet and clinical onset of FOG. We infer that FOG is characterized by high frequency oscillation at the feet, which progresses proximally and is mechanically damped at the torso.

20.
Age (Dordr) ; 36(3): 9648, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24789080

RESUMO

Aging is a progressive process that results in the accumulation of intra- and extracellular alterations that in turn contribute to a reduction in health. Age-related changes in DNA methylation have been reported before and may be responsible for aging-induced changes in gene expression, although a causal relationship has yet to be shown. Using genome-wide assays, we analyzed age-induced changes in DNA methylation and their effect on gene expression with and without transient induction with the synthetic transcription modulating agent WY14,643. To demonstrate feasibility of the approach, we isolated peripheral blood mononucleated cells (PBMCs) from five young and five old healthy male volunteers and cultured them with or without WY14,643. Infinium 450K BeadChip and Affymetrix Human Gene 1.1 ST expression array analysis revealed significant differential methylation of at least 5 % (ΔYO > 5 %) at 10,625 CpG sites between young and old subjects, but only a subset of the associated genes were also differentially expressed. Age-related differential methylation of previously reported epigenetic biomarkers of aging including ELOVL2, FHL2, PENK, and KLF14 was confirmed in our study, but these genes did not display an age-related change in gene expression in PBMCs. Bioinformatic analysis revealed that differentially methylated genes that lack an age-related expression change predominantly represent genes involved in carcinogenesis and developmental processes, and expression of most of these genes were silenced in PBMCs. No changes in DNA methylation were found in genes displaying transiently induced changes in gene expression. In conclusion, aging-induced differential methylation often targets developmental genes and occurs mostly without change in gene expression.


Assuntos
Envelhecimento/genética , Epigênese Genética/genética , Regulação da Expressão Gênica no Desenvolvimento , Leucócitos Mononucleares/metabolismo , RNA/genética , Adulto , Idoso , Envelhecimento/metabolismo , Células Cultivadas , Metilação de DNA , Genoma Humano , Voluntários Saudáveis , Humanos , Leucócitos Mononucleares/citologia , Masculino , Pessoa de Meia-Idade
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