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1.
J Am Coll Cardiol ; 73(24): 3118-3131, 2019 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-31221261

RESUMO

BACKGROUND: Subclinical changes on the electrocardiogram are risk factors for cardiovascular mortality. Recognition and knowledge of electrolyte associations in cardiac electrophysiology are based on only in vitro models and observations in patients with severe medical conditions. OBJECTIVES: This study sought to investigate associations between serum electrolyte concentrations and changes in cardiac electrophysiology in the general population. METHODS: Summary results collected from 153,014 individuals (54.4% women; mean age 55.1 ± 12.1 years) from 33 studies (of 5 ancestries) were meta-analyzed. Linear regression analyses examining associations between electrolyte concentrations (mmol/l of calcium, potassium, sodium, and magnesium), and electrocardiographic intervals (RR, QT, QRS, JT, and PR intervals) were performed. The study adjusted for potential confounders and also stratified by ancestry, sex, and use of antihypertensive drugs. RESULTS: Lower calcium was associated with longer QT intervals (-11.5 ms; 99.75% confidence interval [CI]: -13.7 to -9.3) and JT duration, with sex-specific effects. In contrast, higher magnesium was associated with longer QT intervals (7.2 ms; 99.75% CI: 1.3 to 13.1) and JT. Lower potassium was associated with longer QT intervals (-2.8 ms; 99.75% CI: -3.5 to -2.0), JT, QRS, and PR durations, but all potassium associations were driven by use of antihypertensive drugs. No physiologically relevant associations were observed for sodium or RR intervals. CONCLUSIONS: The study identified physiologically relevant associations between electrolytes and electrocardiographic intervals in a large-scale analysis combining cohorts from different settings. The results provide insights for further cardiac electrophysiology research and could potentially influence clinical practice, especially the association between calcium and QT duration, by which calcium levels at the bottom 2% of the population distribution led to clinically relevant QT prolongation by >5 ms.

2.
JMIR Mhealth Uhealth ; 7(1): e11458, 2019 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-30617040

RESUMO

BACKGROUND: Pregnancy can be distressing, particularly if expectant mothers are worried about the well-being of their fetus. Consequently, the desire for reassurance and frequent fetal monitoring is often pronounced. Smart wearable devices and telemedicine are promising tools that could assist women in self-monitoring their pregnancy at home, hence disburdening emergency departments (EDs). They present the possibility to clarify the need for urgent care remotely and offer tighter pregnancy monitoring. However, patients' acceptance of such new technologies for fetal monitoring has not yet been explored extensively. OBJECTIVE: This survey aimed to elucidate the attitudes of women toward self-monitoring of their pregnancy using noninvasive electronic devices. The technical details of the proposed devices were not specified. METHODS: A cross-sectional multicenter study was conducted at the departments of obstetrics of the University Hospitals of Heidelberg and Leipzig, Germany. All patients seen in the obstetrics clinic who were above 18 years were offered participation. We designed a survey questionnaire including validated instruments covering population characteristics, issues in current and past pregnancies, as well as attitudes toward self-monitoring of pregnancy with smart devices. RESULTS: A total of 509 pregnant women with no previous experience in telemedicine participated. Only a small minority of 5.9% (29/493) regarded self-monitoring with wearable devices as an alternative to consulting their physicians. Along these lines, only 7.7% (38/496) strongly believed they would visit the ED less often if such devices were readily available. However, if the procedure were combined with a Web-based telemetric physician consult, 13.5% (66/487) would be highly motivated to use the devices. Furthermore, significantly more women regarded it as an alternative prior to seeing a doctor when they perceived a decline in fetal movements (P<.001). Interestingly, women with university degrees had a higher propensity to engage in pregnancy self-monitoring compared with women without one (37% vs 23%; P=.001). Of the participants, 77.9% (381/489) would like smart wearable devices to measure fetal heart sounds, and 62.6% (306/489) wished to use the devices on their own. Feedback from a doctor or midwife was also very important in their choice of such devices (61.8%, 301/487 wished feedback). The intended frequency of use differed vastly among women, ranging from 13.8% (65/471) who would like to use such a device several times per day to 31.6% (149/471) who favored once per week at most. CONCLUSIONS: Our results point to a skeptical attitude toward pregnancy self-monitoring among pregnant women. Nevertheless, many women are open to using devices for pregnancy monitoring in parallel to consulting their physician. The intention to use such devices several times daily or weekly, expressed by more than half of the participants, highlights the potential of such technologies.

3.
Arch Gynecol Obstet ; 298(6): 1085-1093, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30264201

RESUMO

PURPOSE: Reduction of maternal morbidity and mortality is a major worldwide objective anchored in the millennium goals of the United Nations. To improve fetal and maternal care, a constant attempt to discover groundbreaking technologies is ongoing. One approach is the enhancement of non-invasive fetal ECG devices. Most importantly, acceptance of new technologies by pregnant women is a prerequisite for successful implementation. METHODS: This questionnaire-based study conducted at the University Hospital Heidelberg, Germany between May and June 2017 evaluates pregnant women's attitudes towards a new device for fetal ECG monitoring and its potential home usage. The study population was questioned after exposure to the Parides/Atlantis prototype (Nemo Healthcare, Veldhoven, The Netherlands), whereas the maternal and gestational age-matched control group was left to envision telemedical topics. RESULTS: The prototype and its potential usage in a clinical and telemedical setting was highly accepted, and its comfort and appearance satisfied participants. Its use caused significantly improved telemedical understanding as envision increased (p = 0.0015). Implementation and integration of telemedical devices into antenatal care was significantly preferred by the study group (p = 0.0011), though participants desire more specific features for their personal use. Optional home-based self-monitoring to reduce scheduled doctoral visits (p = 0.0004) as well as self-assessment prior to self-initiated, unscheduled consultation (p < 0.0001) could be affected positively by such a device. Furthermore, it could reduce face-to-face interaction with the care provider (p = 0.0163). CONCLUSIONS: The positive feedback on remote self-monitoring might open options for a more "patient as partners" oriented prenatal care in the future. Safety and reliability remain a major issue. More comprehensive studies with new technologies are needed to diligently ensure quality of care. Finally, results for new technologies must be communicated to pregnant women for their acceptance and usage of new devices.

4.
JMIR Mhealth Uhealth ; 6(8): e10063, 2018 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-30089606

RESUMO

BACKGROUND: The demand for fetal monitoring and constant reassurance is high in pregnant women. Consequently, pregnant women use various health apps and are more likely to visit emergency departments due to subjective but nonurgent complaints. However, electronic health (eHealth) and mobile health (mHealth) solutions are rarely used to prevent nonurgent emergency consultations. To implement modern care solutions, a better understanding of the attitudes, fears, and hopes of health care professionals toward eHealth and mHealth is needed. OBJECTIVE: The aim of this study was to investigate the attitudes of health care professionals in obstetrics toward telemedicine. METHODS: A quantitative Web-based survey on health care professionals in obstetrics in Germany was conducted. The participants included nurses, midwives, and physicians of all age groups and job positions working in hospitals that provide various levels of health care. The questionnaire comprised 24 questions about the characteristics of the study population, views about emergency consultations in obstetrics, attitude toward telemedicine, job satisfaction, and sleeping behavior. RESULTS: In total, 244 health care professionals participated in the Web-based survey. In general, health care professionals were skeptical (170/233, 72.9%) about the use of telemedicine in obstetrics; however, 55.8% (130/233) recognized its potential. Moreover, 72% (62/86) of physicians were optimistic in using apps for pregnancy monitoring, whereas 36.1% (47/130) of nonphysicians (P<.001) were not. Significantly, more nonphysicians rejected such developments (75/130, 57.7% rejected) compared with physicians (24/86, 28%; P<.001). We also found that obstetricians with more than 10 years of work-experience are more skeptical; however, approximately 49% (18/37) of them believed that telemedicine could reduce nonurgent emergency consultations, whereas 73.2% (106/145) of obstetricians with less than 5 years of experience (P=.01) thought otherwise. Our survey revealed a high job satisfaction and a prevalence of regular sleeping problems of 45.9% (91/198) among health care professionals in obstetrics. Surprisingly, both job satisfaction and sleeping problems were independent from the number of night shifts per month (P=.77 and P=.99, respectively). Yet, 56.6% (112/198) of the survey participants thought they would be happier with their job if they had to work fewer night shifts per month. CONCLUSIONS: Our study reveals an ambivalent attitude toward the use of telemedicine among health care professionals in obstetrics in Germany at the moment. Efforts to promote the use of telemedicine should focus on nurses and midwives because these groups are the most skeptical. By contrast, particularly young physicians recognize the potential of apps in patient care and would like to use such technology in pregnancy monitoring.

5.
JAMA Cardiol ; 3(6): 463-472, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29617535

RESUMO

Importance: Tumor necrosis factor α (TNF-α) is a proinflammatory cytokine with manifold consequences for mammalian pathophysiology, including cardiovascular disease. A deeper understanding of TNF-α biology may enhance treatment precision. Objective: To conduct an epigenome-wide analysis of blood-derived DNA methylation and TNF-α levels and to assess the clinical relevance of findings. Design, Setting, and Participants: This meta-analysis assessed epigenome-wide associations in circulating TNF-α concentrations from 5 cohort studies and 1 interventional trial, with replication in 3 additional cohort studies. Follow-up analyses investigated associations of identified methylation loci with gene expression and incident coronary heart disease; this meta-analysis included 11 461 participants who experienced 1895 coronary events. Exposures: Circulating TNF-α concentration. Main Outcomes and Measures: DNA methylation at approximately 450 000 loci, neighboring DNA sequence variation, gene expression, and incident coronary heart disease. Results: The discovery cohort included 4794 participants, and the replication study included 816 participants (overall mean [SD] age, 60.7 [8.5] years). In the discovery stage, circulating TNF-α levels were associated with methylation of 7 cytosine-phosphate-guanine (CpG) sites, 3 of which were located in or near DTX3L-PARP9 at cg00959259 (ß [SE] = -0.01 [0.003]; P = 7.36 × 10-8), cg08122652 (ß [SE] = -0.008 [0.002]; P = 2.24 × 10-7), and cg22930808(ß [SE] = -0.01 [0.002]; P = 6.92 × 10-8); NLRC5 at cg16411857 (ß [SE] = -0.01 [0.002]; P = 2.14 × 10-13) and cg07839457 (ß [SE] = -0.02 [0.003]; P = 6.31 × 10-10); or ABO, at cg13683939 (ß [SE] = 0.04 [0.008]; P = 1.42 × 10-7) and cg24267699 (ß [SE] = -0.009 [0.002]; P = 1.67 × 10-7), after accounting for multiple testing. Of these, negative associations between TNF-α concentration and methylation of 2 loci in NLRC5 and 1 in DTX3L-14 PARP9 were replicated. Replicated TNF-α-linked CpG sites were associated with 9% to 19% decreased risk of incident coronary heart disease per 10% higher methylation per CpG site (cg16411857: hazard ratio [HR], 0.86; 95% CI, 0.78-1.95; P = .003; cg07839457: HR, 0.89; 95% CI, 0.80-0.94; P = 3.1 × 10-5; cg00959259: HR, 0.91; 95% CI, 0.84-0.97; P = .002; cg08122652: HR, 0.81; 95% CI, 0.74-0.89; P = 2.0 × 10-5). Conclusions and Relevance: We identified and replicated novel epigenetic correlates of circulating TNF-α concentration in blood samples and linked these loci to coronary heart disease risk, opening opportunities for validation and therapeutic applications.

6.
Circ Arrhythm Electrophysiol ; 11(2): e005762, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29440187

RESUMO

BACKGROUND: We developed a novel electrocardiographic marker, T-wave area dispersion (TW-Ad), which measures repolarization heterogeneity by assessing interlead T-wave areas during a single cardiac cycle and tested whether it can identify patients at risk for sudden cardiac death (SCD) in the general population. METHODS AND RESULTS: TW-Ad was measured from standard digital 12-lead ECG in 5618 adults (46% men; age, 50.9±12.5 years) participating in the Health 2000 Study-an epidemiological survey representative of the Finnish adult population. Independent replication was performed in 3831 participants of the KORA S4 Study (Cooperative Health Research in the Region of Augsburg; 49% men; age, 48.7±13.7 years; mean follow-up, 8.8±1.1 years). During follow-up (7.7±1.4 years), 72 SCDs occurred in the Health 2000 Survey. Lower TW-Ad was univariately associated with SCD (0.32±0.36 versus 0.60±0.19; P<0.001); it had an area under the receiver operating characteristic curve of 0.809. TW-Ad (≤0.46) conferred a hazard ratio of 10.8 (95% confidence interval, 6.8-17.4; P<0.001) for SCD; it remained independently predictive of SCD after multivariable adjustment for clinical risk markers (hazard ratio, 4.6; 95% confidence interval, 2.7-7.4; P<0.001). Replication analyses performed in the KORA S4 Study confirmed an increased risk for cardiac death (unadjusted hazard ratio, 5.5; 95% confidence interval, 3.2-9.5; P<0.001; multivariable adjusted hazard ratio, 1.9; 95% confidence interval, 1.1-3.5; P<0.05). CONCLUSION: Low TW-Ad, reflecting increased heterogeneity of repolarization, in standard 12-lead resting ECGs is a powerful and independent predictor of SCD in the adult general population.

7.
Mol Ecol ; 27(3): 723-736, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29319892

RESUMO

Theory postulates that dietary specialization in mammalian herbivores is enabled by a specialized set of liver enzymes that process the high concentrations of similar plant secondary metabolites (PSMs) in the diets of specialists. To investigate whether qualitative and quantitative differences in detoxification mechanisms distinguish dietary specialists from generalists, we compared the sequence diversity and gene copy number of detoxification enzymes in two woodrat species: a generalist, the white-throated woodrat (Neotoma albigula) and a juniper specialist, Stephens' woodrat (N. stephensi). We focused on enzymes in the cytochrome P450 subfamily 2B (CYP2B), because previous research suggests this subfamily plays a key role in the processing of PSMs. For both woodrat species, we obtained and sequenced CYP2B cDNA, generated CYP2B phylogenies, estimated CYP2B gene copy number and created a homology model of the active site. We found that the specialist possessed on average ~5 more CYP2B gene copies than the generalist, but the specialist's CYP2B sequences were less diverse. Phylogenetic analysis of putative CYP2B homologs resolved woodrat species as reciprocally monophyletic and suggested evolutionary convergence of distinct homologs on similar key amino acid residues in both species. Homology modelling of the CYP2B enzyme suggests that interspecific differences in substrate preference and function likely result from amino acid differences in the enzyme active site. The characteristics of CYP2B in the specialist, that is greater gene copy number coupled with less sequence variation, are consistent with specialization to a narrow range of dietary toxins.

8.
Front Plant Sci ; 8: 1995, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29209354

RESUMO

Multiple lepidopteran larvae feed successfully on plants containing glucosinolates despite the diverse array of toxic and deterrent breakdown products, such as isothiocyanates (ITCs), formed upon plant damage. While much is known about how specialist lepidopterans metabolize and tolerate glucosinolates, there is little information about the metabolic fate of these plant defense compounds in specialized herbivores. Employing 13C- and 14C-labeled 4-methylsulfinylbutyl glucosinolate (glucoraphanin), we identified and quantified the major detoxification products of glucosinolates and ITCs in selected specialized and generalist larvae. While specialists prevented glucosinolate hydrolysis or diverted hydrolysis to form nitriles, hydrolysis in generalists proceeded to toxic ITCs, of which a portion were conjugated to glutathione. However, a large amount of ITCs remained unmodified, which may have led to the observed negative effects on growth and development. The performance of two generalist-feeding caterpillars, Spodoptera littoralis (African cotton leafworm) and Mamestra brassicae (cabbage moth) on Arabidopsis thaliana Col-0 and various glucosinolate-deficient mutants was investigated from hatching until pupation. We found that glucosinolates negatively affected larval growth and development, but not survival, with aliphatic glucosinolates having stronger effects than indolic glucosinolates, and the combination of the two glucosinolate types being even more detrimental to growth and development. Curiously, last instar larvae grew better on wild type than on non-glucosinolate-containing plant lines, but this could not be attributed to a change in detoxification rate or feeding behavior. Glucosinolates thus appear to be effective defenses against generalist lepidopteran herbivores at least during most stages of larval development. Nevertheless, the reversal of negative effects in the oldest instar is intriguing, and further investigation of this phenomenon may shed light on how generalists adjust their physiology to feed on diets with many different types of plant defense compounds.

9.
Hypertension ; 70(4): 743-750, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28784648

RESUMO

Hypertension represents a major cardiovascular risk factor. The pathophysiology of increased blood pressure (BP) is not yet completely understood. Transcriptome profiling offers possibilities to uncover genetics effects on BP. Based on 2 populations including 2549 individuals, a meta-analyses of monocytic transcriptome-wide profiles were performed to identify transcripts associated with BP. Replication was performed in 2 independent studies of whole-blood transcriptome data including 1990 individuals. For identified candidate genes, a direct link between long-term changes in BP and gene expression over time and by treatment with BP-lowering therapy was assessed. The predictive value of protein levels encoded by candidate genes for subsequent cardiovascular disease was investigated. Eight transcripts (CRIP1, MYADM, TIPARP, TSC22D3, CEBPA, F12, LMNA, and TPPP3) were identified jointly accounting for up to 13% (95% confidence interval, 8.7-16.2) of BP variability. Changes in CRIP1, MYADM, TIPARP, LMNA, TSC22D3, CEBPA, and TPPP3 expression associated with BP changes-among these, CRIP1 gene expression was additionally correlated to measures of cardiac hypertrophy. Assessment of circulating CRIP1 (cystein-rich protein 1) levels as biomarkers showed a strong association with increased risk for incident stroke (hazard ratio, 1.06; 95% confidence interval, 1.03-1.09; P=5.0×10-5). Our comprehensive analysis of global gene expression highlights 8 novel transcripts significantly associated with BP, providing a link between gene expression and BP. Translational approaches further established evidence for the potential use of CRIP1 as emerging disease-related biomarker.


Assuntos
Proteínas de Transporte/genética , Hipertensão , Proteínas com Domínio LIM/genética , Acidente Vascular Cerebral , Adulto , Pressão Sanguínea/genética , Determinação da Pressão Arterial/métodos , Determinação da Pressão Arterial/estatística & dados numéricos , Proteínas Estimuladoras de Ligação a CCAAT/genética , Feminino , Expressão Gênica , Perfilação da Expressão Gênica , Estudo de Associação Genômica Ampla , Humanos , Hipertensão/diagnóstico , Hipertensão/genética , Masculino , Proteínas Proteolipídicas Associadas a Linfócitos e Mielina/genética , Poli(ADP-Ribose) Polimerases/genética , Polimorfismo de Nucleotídeo Único , Fatores de Risco , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/prevenção & controle , Fatores de Transcrição/genética
10.
Genome Biol ; 17(1): 255, 2016 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-27955697

RESUMO

BACKGROUND: Chronic low-grade inflammation reflects a subclinical immune response implicated in the pathogenesis of complex diseases. Identifying genetic loci where DNA methylation is associated with chronic low-grade inflammation may reveal novel pathways or therapeutic targets for inflammation. RESULTS: We performed a meta-analysis of epigenome-wide association studies (EWAS) of serum C-reactive protein (CRP), which is a sensitive marker of low-grade inflammation, in a large European population (n = 8863) and trans-ethnic replication in African Americans (n = 4111). We found differential methylation at 218 CpG sites to be associated with CRP (P < 1.15 × 10-7) in the discovery panel of European ancestry and replicated (P < 2.29 × 10-4) 58 CpG sites (45 unique loci) among African Americans. To further characterize the molecular and clinical relevance of the findings, we examined the association with gene expression, genetic sequence variants, and clinical outcomes. DNA methylation at nine (16%) CpG sites was associated with whole blood gene expression in cis (P < 8.47 × 10-5), ten (17%) CpG sites were associated with a nearby genetic variant (P < 2.50 × 10-3), and 51 (88%) were also associated with at least one related cardiometabolic entity (P < 9.58 × 10-5). An additive weighted score of replicated CpG sites accounted for up to 6% inter-individual variation (R2) of age-adjusted and sex-adjusted CRP, independent of known CRP-related genetic variants. CONCLUSION: We have completed an EWAS of chronic low-grade inflammation and identified many novel genetic loci underlying inflammation that may serve as targets for the development of novel therapeutic interventions for inflammation.


Assuntos
Proteína C-Reativa/genética , Epigênese Genética , Inflamação/genética , Locos de Características Quantitativas/genética , Afro-Americanos , Ilhas de CpG/genética , Metilação de DNA/genética , Grupo com Ancestrais do Continente Europeu , Feminino , Expressão Gênica , Variação Genética , Estudo de Associação Genômica Ampla , Humanos , Inflamação/sangue , Masculino , Motivos de Nucleotídeos/genética
11.
PLoS One ; 11(3): e0152314, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27019061

RESUMO

Epigenetic regulation has been postulated to affect glucose metabolism, insulin sensitivity and the risk of type 2 diabetes. Therefore, we performed an epigenome-wide association study for measures of glucose metabolism in whole blood samples of the population-based Cooperative Health Research in the Region of Augsburg F4 study using the Illumina HumanMethylation 450 BeadChip. We identified a total of 31 CpG sites where methylation level was associated with measures of glucose metabolism after adjustment for age, sex, smoking, and estimated white blood cell proportions and correction for multiple testing using the Benjamini-Hochberg (B-H) method (four for fasting glucose, seven for fasting insulin, 25 for homeostasis model assessment-insulin resistance [HOMA-IR]; B-H-adjusted p-values between 9.2x10(-5) and 0.047). In addition, DNA methylation at cg06500161 (annotated to ABCG1) was associated with all the aforementioned phenotypes and 2-hour glucose (B-H-adjusted p-values between 9.2x10(-5) and 3.0x10(-3)). Methylation status of additional three CpG sites showed an association with fasting insulin only after additional adjustment for body mass index (BMI) (B-H-adjusted p-values = 0.047). Overall, effect strengths were reduced by around 30% after additional adjustment for BMI, suggesting that this variable has an influence on the investigated phenotypes. Furthermore, we found significant associations between methylation status of 21 of the aforementioned CpG sites and 2-hour insulin in a subset of samples with seven significant associations persisting after additional adjustment for BMI. In a subset of 533 participants, methylation of the CpG site cg06500161 (ABCG1) was inversely associated with ABCG1 gene expression (B-H-adjusted p-value = 1.5x10(-9)). Additionally, we observed an enrichment of the top 1,000 CpG sites for diabetes-related canonical pathways using Ingenuity Pathway Analysis. In conclusion, our study indicates that DNA methylation and diabetes-related traits are associated and that these associations are partially BMI-dependent. Furthermore, the interaction of ABCG1 with glucose metabolism is modulated by epigenetic processes.


Assuntos
Metilação de DNA , Diabetes Mellitus Tipo 2/genética , Estudo de Associação Genômica Ampla , Glucose/metabolismo , Membro 1 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Glicemia/análise , Índice de Massa Corporal , Ilhas de CpG , DNA/análise , DNA/sangue , DNA/isolamento & purificação , Diabetes Mellitus Tipo 2/patologia , Epigênese Genética , Feminino , Alemanha , Teste de Tolerância a Glucose , Humanos , Insulina/análise , Masculino , Pessoa de Meia-Idade , Fenótipo
12.
Hum Mol Genet ; 25(21): 4611-4623, 2016 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-28158590

RESUMO

Cigarette smoking is a leading modifiable cause of death worldwide. We hypothesized that cigarette smoking induces extensive transcriptomic changes that lead to target-organ damage and smoking-related diseases. We performed a meta-analysis of transcriptome-wide gene expression using whole blood-derived RNA from 10,233 participants of European ancestry in six cohorts (including 1421 current and 3955 former smokers) to identify associations between smoking and altered gene expression levels. At a false discovery rate (FDR) <0.1, we identified 1270 differentially expressed genes in current vs. never smokers, and 39 genes in former vs. never smokers. Expression levels of 12 genes remained elevated up to 30 years after smoking cessation, suggesting that the molecular consequence of smoking may persist for decades. Gene ontology analysis revealed enrichment of smoking-related genes for activation of platelets and lymphocytes, immune response, and apoptosis. Many of the top smoking-related differentially expressed genes, including LRRN3 and GPR15, have DNA methylation loci in promoter regions that were recently reported to be hypomethylated among smokers. By linking differential gene expression with smoking-related disease phenotypes, we demonstrated that stroke and pulmonary function show enrichment for smoking-related gene expression signatures. Mediation analysis revealed the expression of several genes (e.g. ALAS2) to be putative mediators of the associations between smoking and inflammatory biomarkers (IL6 and C-reactive protein levels). Our transcriptomic study provides potential insights into the effects of cigarette smoking on gene expression in whole blood and their relations to smoking-related diseases. The results of such analyses may highlight attractive targets for treating or preventing smoking-related health effects.


Assuntos
Fumar Cigarros/genética , Expressão Gênica/efeitos dos fármacos , Adulto , Idoso , Fumar Cigarros/sangue , Estudos de Coortes , Ilhas de CpG , Metilação de DNA , Grupo com Ancestrais do Continente Europeu/genética , Feminino , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/genética , Humanos , Leucócitos/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Fumar/genética , Transcriptoma/efeitos dos fármacos
13.
Methods Mol Biol ; 1368: 85-97, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26614070

RESUMO

Microarray profiling of gene expression is widely applied to studies in molecular biology and functional genomics. Experimental and technical variations make not only the statistical analysis of single studies but also meta-analyses of different studies very challenging. Here, we describe the analytical steps required to substantially reduce the variations of gene expression data without affecting true effect sizes. A software pipeline has been established using gene expression data from a total of 3358 whole blood cell and blood monocyte samples, all from three German population-based cohorts, measured on the Illumina HumanHT-12 v3 BeadChip array. In summary, adjustment for a few selected technical factors greatly improved reliability of gene expression analyses. Such adjustments are particularly required for meta-analyses of different studies.


Assuntos
Perfilação da Expressão Gênica/métodos , Monócitos/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Análise de Variância , Feminino , Humanos , Masculino , Técnicas de Amplificação de Ácido Nucleico , Hibridização de Ácido Nucleico , Fenótipo , Controle de Qualidade , RNA Mensageiro/genética , RNA Mensageiro/isolamento & purificação , Coloração e Rotulagem
14.
J Chem Ecol ; 41(12): 1059-68, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26631406

RESUMO

To be considered a dietary specialist, mammalian herbivores must consume large quantities of a plant species considered "difficult" with respect to nutrient or toxin content, and possess specialized adaptations to deal with plant defensive compounds or low nutritional content. Populations of Neotoma lepida in the Great Basin consume Juniperus osteosperma, a plant heavily defended by terpenes, but a detailed dietary analysis of this population is lacking. Therefore, we investigated the extent of dietary specialization in this species in comparison with the better-studied specialist species, N. stephensi. Microhistological analysis of feces from N. lepida revealed that greater than 90% of their diet in nature was comprised of juniper. In laboratory tolerance trials, N. lepida tolerated a diet of 80% J. osteosperma, similar to that observed for N. stephensi. There was no difference in the abilities of N. lepida and N. stephensi to metabolize hexobarbital, a proxy compound for terpene metabolism. In preference tests of native and non-native juniper species, N. lepida did not exhibit a preference for its native or co-occurring juniper, J. osteosperma, over the non-native species, J. monosperma, whereas N. stephensi preferred its native or co-occurring juniper J. monosperma over non-native J. osteosperma. Behavioral and habitat differences between these woodrat species lead to the categorization of N. stephensi as an obligate juniper specialist with a small range that overlaps that of its preferred food, J. monosperma, and N. lepida as a facultative juniper specialist with a large range, and only a portion of its distribution containing populations that feed extensively on J. osteosperma.


Assuntos
Dieta , Herbivoria , Sigmodontinae/fisiologia , Animais , Clima Desértico , Ecossistema , Fezes/química , Hexobarbital/metabolismo , Juniperus , Especificidade da Espécie , Utah
15.
Artigo em Inglês | MEDLINE | ID: mdl-26500701

RESUMO

BACKGROUND: Disease risk and incidence between males and females reveal differences, and sex is an important component of any investigation of the determinants of phenotypes or disease etiology. Further striking differences between men and women are known, for instance, at the metabolic level. The extent to which men and women vary at the level of the epigenome, however, is not well documented. DNA methylation is the best known epigenetic mechanism to date. RESULTS: In order to shed light on epigenetic differences, we compared autosomal DNA methylation levels between men and women in blood in a large prospective European cohort of 1799 subjects, and replicated our findings in three independent European cohorts. We identified and validated 1184 CpG sites to be differentially methylated between men and women and observed that these CpG sites were distributed across all autosomes. We showed that some of the differentially methylated loci also exhibit differential gene expression between men and women. Finally, we found that the differentially methylated loci are enriched among imprinted genes, and that their genomic location in the genome is concentrated in CpG island shores. CONCLUSION: Our epigenome-wide association study indicates that differences between men and women are so substantial that they should be considered in design and analyses of future studies.

16.
Nat Commun ; 6: 8570, 2015 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-26490707

RESUMO

Disease incidences increase with age, but the molecular characteristics of ageing that lead to increased disease susceptibility remain inadequately understood. Here we perform a whole-blood gene expression meta-analysis in 14,983 individuals of European ancestry (including replication) and identify 1,497 genes that are differentially expressed with chronological age. The age-associated genes do not harbor more age-associated CpG-methylation sites than other genes, but are instead enriched for the presence of potentially functional CpG-methylation sites in enhancer and insulator regions that associate with both chronological age and gene expression levels. We further used the gene expression profiles to calculate the 'transcriptomic age' of an individual, and show that differences between transcriptomic age and chronological age are associated with biological features linked to ageing, such as blood pressure, cholesterol levels, fasting glucose, and body mass index. The transcriptomic prediction model adds biological relevance and complements existing epigenetic prediction models, and can be used by others to calculate transcriptomic age in external cohorts.


Assuntos
Envelhecimento/sangue , Transcriptoma , Biomarcadores/sangue , Metilação de DNA , Grupo com Ancestrais do Continente Europeu , Perfilação da Expressão Gênica , Humanos
17.
BMC Med Genomics ; 8: 65, 2015 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-26470795

RESUMO

BACKGROUND: Obesity, defined as pathologically increased body mass index (BMI), is strongly related to an increased risk for numerous common cardiovascular and metabolic diseases. It is particularly associated with insulin resistance, hyperglycemia, and systemic oxidative stress and represents the most important risk factor for type 2 diabetes (T2D). However, the pathophysiological mechanisms underlying these associations are still not completely understood. Therefore, in order to identify potentially disease-relevant BMI-associated gene expression signatures, a transcriptome-wide association study (TWAS) on BMI was performed. METHODS: Whole-blood mRNA levels determined by array-based transcriptional profiling were correlated with BMI in two large independent population-based cohort studies (KORA F4 and SHIP-TREND) comprising a total of 1977 individuals. RESULTS: Extensive alterations of the whole-blood transcriptome were associated with BMI: More than 3500 transcripts exhibited significant positive or negative BMI-correlation. Three major whole-blood gene expression signatures associated with increased BMI were identified. The three signatures suggested: i) a ratio shift from mature erythrocytes towards reticulocytes, ii) decreased expression of several genes essentially involved in the transmission and amplification of the insulin signal, and iii) reduced expression of several key genes involved in the defence against reactive oxygen species (ROS). CONCLUSIONS: Whereas the first signature confirms published results, the other two provide possible mechanistic explanations for well-known epidemiological findings under conditions of increased BMI, namely attenuated insulin signaling and increased oxidative stress. The putatively causative BMI-dependent down-regulation of the expression of numerous genes on the mRNA level represents a novel finding. BMI-associated negative transcriptional regulation of insulin signaling and oxidative stress management provide new insights into the pathogenesis of metabolic syndrome and T2D.


Assuntos
Sangue/metabolismo , Índice de Massa Corporal , Perfilação da Expressão Gênica , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Humanos , Insulina/metabolismo , Masculino , Pessoa de Meia-Idade , Estresse Oxidativo/genética , RNA Mensageiro/genética , Espécies Reativas de Oxigênio/metabolismo , Reticulócitos/metabolismo , Transdução de Sinais/genética
18.
PLoS Genet ; 11(6): e1005274, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26086077

RESUMO

Biological systems consist of multiple organizational levels all densely interacting with each other to ensure function and flexibility of the system. Simultaneous analysis of cross-sectional multi-omics data from large population studies is a powerful tool to comprehensively characterize the underlying molecular mechanisms on a physiological scale. In this study, we systematically analyzed the relationship between fasting serum metabolomics and whole blood transcriptomics data from 712 individuals of the German KORA F4 cohort. Correlation-based analysis identified 1,109 significant associations between 522 transcripts and 114 metabolites summarized in an integrated network, the 'human blood metabolome-transcriptome interface' (BMTI). Bidirectional causality analysis using Mendelian randomization did not yield any statistically significant causal associations between transcripts and metabolites. A knowledge-based interpretation and integration with a genome-scale human metabolic reconstruction revealed systematic signatures of signaling, transport and metabolic processes, i.e. metabolic reactions mainly belonging to lipid, energy and amino acid metabolism. Moreover, the construction of a network based on functional categories illustrated the cross-talk between the biological layers at a pathway level. Using a transcription factor binding site enrichment analysis, this pathway cross-talk was further confirmed at a regulatory level. Finally, we demonstrated how the constructed networks can be used to gain novel insights into molecular mechanisms associated to intermediate clinical traits. Overall, our results demonstrate the utility of a multi-omics integrative approach to understand the molecular mechanisms underlying both normal physiology and disease.


Assuntos
Jejum/sangue , Redes Reguladoras de Genes , Metaboloma , Transcriptoma , Idoso , Feminino , Genoma Humano , Humanos , Masculino , Pessoa de Meia-Idade
19.
PLoS Genet ; 11(5): e1005223, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25955312

RESUMO

The functional consequences of trait associated SNPs are often investigated using expression quantitative trait locus (eQTL) mapping. While trait-associated variants may operate in a cell-type specific manner, eQTL datasets for such cell-types may not always be available. We performed a genome-environment interaction (GxE) meta-analysis on data from 5,683 samples to infer the cell type specificity of whole blood cis-eQTLs. We demonstrate that this method is able to predict neutrophil and lymphocyte specific cis-eQTLs and replicate these predictions in independent cell-type specific datasets. Finally, we show that SNPs associated with Crohn's disease preferentially affect gene expression within neutrophils, including the archetypal NOD2 locus.


Assuntos
Linfócitos/citologia , Neutrófilos/citologia , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Linhagem Celular , Doença de Crohn/genética , Regulação da Expressão Gênica , Estudo de Associação Genômica Ampla/métodos , Humanos , Linfócitos/metabolismo , Neutrófilos/metabolismo , Proteína Adaptadora de Sinalização NOD2/genética , Proteína Adaptadora de Sinalização NOD2/metabolismo , Fenótipo , Análise de Componente Principal , Reprodutibilidade dos Testes
20.
BMC Med ; 13: 48, 2015 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-25857605

RESUMO

BACKGROUND: Excess body weight is a major risk factor for cardiometabolic diseases. The complex molecular mechanisms of body weight change-induced metabolic perturbations are not fully understood. Specifically, in-depth molecular characterization of long-term body weight change in the general population is lacking. Here, we pursued a multi-omic approach to comprehensively study metabolic consequences of body weight change during a seven-year follow-up in a large prospective study. METHODS: We used data from the population-based Cooperative Health Research in the Region of Augsburg (KORA) S4/F4 cohort. At follow-up (F4), two-platform serum metabolomics and whole blood gene expression measurements were obtained for 1,631 and 689 participants, respectively. Using weighted correlation network analysis, omics data were clustered into modules of closely connected molecules, followed by the formation of a partial correlation network from the modules. Association of the omics modules with previous annual percentage weight change was then determined using linear models. In addition, we performed pathway enrichment analyses, stability analyses, and assessed the relation of the omics modules with clinical traits. RESULTS: Four metabolite and two gene expression modules were significantly and stably associated with body weight change (P-values ranging from 1.9 × 10(-4) to 1.2 × 10(-24)). The four metabolite modules covered major branches of metabolism, with VLDL, LDL and large HDL subclasses, triglycerides, branched-chain amino acids and markers of energy metabolism among the main representative molecules. One gene expression module suggests a role of weight change in red blood cell development. The other gene expression module largely overlaps with the lipid-leukocyte (LL) module previously reported to interact with serum metabolites, for which we identify additional co-expressed genes. The omics modules were interrelated and showed cross-sectional associations with clinical traits. Moreover, weight gain and weight loss showed largely opposing associations with the omics modules. CONCLUSIONS: Long-term weight change in the general population globally associates with serum metabolite concentrations. An integrated metabolomics and transcriptomics approach improved the understanding of molecular mechanisms underlying the association of weight gain with changes in lipid and amino acid metabolism, insulin sensitivity, mitochondrial function as well as blood cell development and function.


Assuntos
Expressão Gênica/fisiologia , Metaboloma/fisiologia , Ganho de Peso/fisiologia , Adulto , Estudos de Coortes , Estudos Transversais , Feminino , Redes Reguladoras de Genes , Humanos , Modelos Lineares , Metabolômica , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco
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