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1.
Gastroenterology ; 162(4): 1160-1170.e1, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34995536

RESUMO

BACKGROUND & AIMS: Hepatocellular carcinogenesis of hepatitis B virus (HBV) infection may arise from integration of viral DNA into the host genome. We aimed to gauge the effect of viral inhibition on transcriptionally active HBV-host integration events and explore the correlation of viral integrations with host gene dysregulation. METHODS: We leveraged data and biospecimens from an interventional trial, in which patients with HBV viremia above 2000 IU/mL and minimally raised serum liver enzyme were randomized to receive tenofovir disoproxil fumarate (TDF) or placebo for 3 years. Total RNA-sequencing was performed on paired liver biopsies taken before and after the 3-year intervention in 119 patients. Virus-host chimeric reads were captured to quantify the number of distinct viral integrations. Dysregulation of a host gene disrupted by viral integration was defined by aberrant expression >2 standard deviations away from samples without viral integration. RESULTS: The TDF (n = 64) and placebo groups (n = 55) were comparable at baseline. Expressed viral integrations were detected in all pre- and posttreatment samples. The number of distinct viral integrations significantly correlated with circulatory biomarkers indicative of viral activities including HBV DNA, RNA, and viral antigens (P < .0003 for all correlations). Moreover, TDF vs placebo achieved a significantly greater reduction in distinct viral integrations, with 3.28-fold and 1.81-fold decreases in the expressed integrations per million reads, respectively (analysis of covariance, P = .037). Besides, viral integrations significantly correlated with host gene dysregulation. CONCLUSION: Inhibition of viral replication reduces the number of transcriptionally active distinct HBV-host DNA integrations in patients with substantial viremia. Given the mutagenic potentials of viral integrations, such treatment effects should be considered in patient management.


Assuntos
Hepatite B Crônica , Hepatite B , Antivirais/farmacologia , Antivirais/uso terapêutico , DNA Viral/genética , Hepatite B/tratamento farmacológico , Hepatite B/genética , Vírus da Hepatite B , Hepatite B Crônica/tratamento farmacológico , Humanos , RNA , Tenofovir/uso terapêutico , Resultado do Tratamento , Carga Viral , Viremia/tratamento farmacológico , Viremia/genética , Integração Viral , Replicação Viral
2.
Am J Hum Genet ; 103(4): 535-552, 2018 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-30290150

RESUMO

Although recent studies provide evidence for a common genetic basis between complex traits and Mendelian disorders, a thorough quantification of their overlap in a phenotype-specific manner remains elusive. Here, we have quantified the overlap of genes identified through large-scale genome-wide association studies (GWASs) for 62 complex traits and diseases with genes containing mutations known to cause 20 broad categories of Mendelian disorders. We identified a significant enrichment of genes linked to phenotypically matched Mendelian disorders in GWAS gene sets; of the total 1,240 comparisons, a higher proportion of phenotypically matched or related pairs (n = 50 of 92 [54%]) than phenotypically unmatched pairs (n = 27 of 1,148 [2%]) demonstrated significant overlap, confirming a phenotype-specific enrichment pattern. Further, we observed elevated GWAS effect sizes near genes linked to phenotypically matched Mendelian disorders. Finally, we report examples of GWAS variants localized at the transcription start site or physically interacting with the promoters of genes linked to phenotypically matched Mendelian disorders. Our results are consistent with the hypothesis that genes that are disrupted in Mendelian disorders are dysregulated by non-coding variants in complex traits and demonstrate how leveraging findings from related Mendelian disorders and functional genomic datasets can prioritize genes that are putatively dysregulated by local and distal non-coding GWAS variants.


Assuntos
Herança Multifatorial/genética , Polimorfismo de Nucleotídeo Único/genética , Locos de Características Quantitativas/genética , Feminino , Predisposição Genética para Doença/genética , Estudo de Associação Genômica Ampla/métodos , Humanos , Masculino , Fenótipo , Regiões Promotoras Genéticas/genética , Sítio de Iniciação de Transcrição/fisiologia
3.
Opt Express ; 26(21): 28002-28012, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-30469856

RESUMO

Integrated optical computing attracts increasing interest recently as Moore's law approaches the physical limitation. Among all the approaches of integrated optical computing, directed logic that takes the full advantage of integrated photonics and electronics has received lots of investigation since its first introduction in 2007. Meanwhile, as integrated photonics matures, it has become critical to develop automated methods for synthesizing optical devices for large-scale optical designs. In this paper, we propose a general electro-optic (EO) logic in a higher level to explore its potential in integrated computing. Compared to the directed logic, the EO logic leads to a briefer design with shorter optical paths and fewer components. Then a comprehensive gate library based on EO logic is summarized. At last, an And-Inverter Graphs (AIGs) based automated logic synthesis algorithm is described as an example to implement the EO logic, which offers an instruction for the design automation of high-speed integrated optical computing circuits.

4.
Opt Lett ; 43(5): 983-986, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29489761

RESUMO

Due to the projected saturation of Moore's law, as well as the drastically increasing trend of bandwidth with lower power consumption, silicon photonics has emerged as one of the most promising alternatives that has attracted a lasting interest due to the accessibility and maturity of ultra-compact passive and active integrated photonic components. In this Letter, we demonstrate a ripple-carry electro-optic 2-bit full adder using microdisks, which replaces the core part of an electrical full adder by optical counterparts and uses light to carry signals from one bit to the next with high bandwidth and low power consumption per bit. All control signals of the operands are applied simultaneously within each clock cycle. Thus, the severe latency issue that accumulates as the size of the full adder increases can be circumvented, allowing for an improvement in computing speed and a reduction in power consumption. This approach paves the way for future high-speed optical computing systems in the post-Moore's law era.

5.
EBioMedicine ; 106: 105232, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38991381

RESUMO

BACKGROUND: Abdominal obesity increases the risk for non-alcoholic fatty liver disease (NAFLD), now known as metabolic dysfunction-associated steatotic liver disease (MASLD). METHODS: To elucidate the directional cell-type level biological mechanisms underlying the association between abdominal obesity and MASLD, we integrated adipose and liver single nucleus RNA-sequencing and bulk cis-expression quantitative trait locus (eQTL) data with the UK Biobank genome-wide association study (GWAS) data using colocalization. Then we used colocalized cis-eQTL variants as instrumental variables in Mendelian randomization (MR) analyses, followed by functional validation experiments on the target genes of the cis-eQTL variants. FINDINGS: We identified 17 colocalized abdominal obesity GWAS variants, regulating 17 adipose cell-type marker genes. Incorporating these 17 variants into MR discovers a putative tissue-of-origin, cell-type-aware causal effect of abdominal obesity on MASLD consistently with multiple MR methods without significant evidence for pleiotropy or heterogeneity. Single cell data confirm the adipocyte-enriched mean expression of the 17 genes. Our cellular experiments across human adipogenesis identify risk variant -specific epigenetic and transcriptional mechanisms. Knocking down two of the 17 genes, PPP2R5A and SH3PXD2B, shows a marked decrease in adipocyte lipidation and significantly alters adipocyte function and adipogenesis regulator genes, including DGAT2, LPL, ADIPOQ, PPARG, and SREBF1. Furthermore, the 17 genes capture a characteristic MASLD expression signature in subcutaneous adipose tissue. INTERPRETATION: Overall, we discover a significant cell-type level effect of abdominal obesity on MASLD and trace its biological effect to adipogenesis. FUNDING: NIH grants R01HG010505, R01DK132775, and R01HL170604; the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program (Grant No. 802825), Academy of Finland (Grants Nos. 333021), the Finnish Foundation for Cardiovascular Research the Sigrid Jusélius Foundation and the Jane and Aatos Erkko Foundation; American Association for the Study of Liver Diseases (AASLD) Advanced Transplant Hepatology award and NIH/NIDDK (P30DK41301) Pilot and Feasibility award; NIH/NIEHS F32 award (F32ES034668); Finnish Diabetes Research Foundation, Kuopio University Hospital Project grant (EVO/VTR grants 2005-2021), the Academy of Finland grant (Contract no. 138006); Academy of Finland (Grant Nos 335443, 314383, 272376 and 266286), Sigrid Jusélius Foundation, Finnish Medical Foundation, Finnish Diabetes Research Foundation, Novo Nordisk Foundation (#NNF20OC0060547, NNF17OC0027232, NNF10OC1013354) and Government Research Funds to Helsinki University Hospital; Orion Research Foundation, Maud Kuistila Foundation, Finish Medical Foundation, and University of Helsinki.

6.
Commun Med (Lond) ; 3(1): 2, 2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36596885

RESUMO

BACKGROUND: Remdesivir (RDV) is an intravenous antiviral with activity against SARS-CoV-2 for treatment of hospitalized COVID-19 patients with moderate-to-severe disease. Biomarkers associated with clinical outcomes have been identified for COVID-19, but few evaluated in context of antiviral treatment. Here, we assessed baseline (day 1, prior to first RDV dose) biomarkers and the impact of RDV treatment on longitudinal biomarker readouts. METHODS: Recently, RDV was evaluated in high-risk, non-hospitalized patients with confirmed SARS-CoV-2 infection and was highly effective at preventing disease progression. The randomized, double-blind, placebo-controlled Phase 3 study included 562 participants who received at least 1 dose of study drug, of which 312 consented for longitudinal biomarker assessments at baseline, day 3, and day 14. We assessed sixteen baseline biomarkers and the impact of RDV treatment on longitudinal biomarker readouts. RESULTS: Six well-known, inflammation-associated biomarkers are elevated at baseline in participants meeting the primary endpoint of hospitalization or death by day 28. Moreover, in comparison to placebo, biomarkers in RDV-treated participants show accelerated improvement, including reduction of soluble angiopoietin-2, D-dimer, and neutrophil-to-lymphocyte ratio, as well as an increase in lymphocyte counts. CONCLUSIONS: Overall, the findings in this study suggest that RDV treatment may accelerate the improvement of multiple biomarkers of COVID-19 severity, which are associated with better clinical outcomes during infection. These findings have implications for better understanding the activity of antiviral treatments in COVID-19.


Certain cells and proteins in the blood can act as markers of COVID-19 severity. However, little is known about the impact of antiviral treatments on these markers. Here, we measured protein and cell markers in patient samples before treatment and those taken during the course of COVID-19 in high-risk non-hospitalized patients treated with or without the antiviral remdesivir (RDV). Several markers were improved with RDV treatment, including those associated with normal responses from the immune system and factors involved in blood clotting. These findings further our understanding of the activity of antivirals in COVID-19 and inform future studies to understand how patients with an increased risk of COVID-19 disease progression respond to these treatments.

7.
Nat Commun ; 14(1): 4214, 2023 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-37452040

RESUMO

Obesity-induced adipose tissue dysfunction can cause low-grade inflammation and downstream obesity comorbidities. Although preadipocytes may contribute to this pro-inflammatory environment, the underlying mechanisms are unclear. We used human primary preadipocytes from body mass index (BMI) -discordant monozygotic (MZ) twin pairs to generate epigenetic (ATAC-sequence) and transcriptomic (RNA-sequence) data for testing whether increased BMI alters the subnuclear compartmentalization of open chromatin in the twins' preadipocytes, causing downstream inflammation. Here we show that the co-accessibility of open chromatin, i.e. compartmentalization of chromatin activity, is altered in the higher vs lower BMI MZ siblings for a large subset ( ~ 88.5 Mb) of the active subnuclear compartments. Using the UK Biobank we show that variants within these regions contribute to systemic inflammation through interactions with BMI on C-reactive protein. In summary, open chromatin co-accessibility in human preadipocytes is disrupted among the higher BMI siblings, suggesting a mechanism how obesity may lead to inflammation via gene-environment interactions.


Assuntos
Inflamação , Obesidade , Humanos , Índice de Massa Corporal , Cromatina , Inflamação/genética , Obesidade/metabolismo , Gêmeos Monozigóticos
8.
Cell Rep Med ; 4(4): 101016, 2023 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-37075704

RESUMO

Nonalcoholic steatohepatitis (NASH) is the most common chronic liver disease globally and a leading cause for liver transplantation in the US. Its pathogenesis remains imprecisely defined. We combined two high-resolution modalities to tissue samples from NASH clinical trials, machine learning (ML)-based quantification of histological features and transcriptomics, to identify genes that are associated with disease progression and clinical events. A histopathology-driven 5-gene expression signature predicted disease progression and clinical events in patients with NASH with F3 (pre-cirrhotic) and F4 (cirrhotic) fibrosis. Notably, the Notch signaling pathway and genes implicated in liver-related diseases were enriched in this expression signature. In a validation cohort where pharmacologic intervention improved disease histology, multiple Notch signaling components were suppressed.


Assuntos
Aprendizado Profundo , Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatopatia Gordurosa não Alcoólica/complicações , Transcriptoma/genética , Progressão da Doença , Cirrose Hepática/genética , Cirrose Hepática/tratamento farmacológico
9.
EBioMedicine ; 92: 104620, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37224770

RESUMO

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) is a fast-growing, underdiagnosed, epidemic. We hypothesise that obesity-related inflammation compromises adipose tissue functions, preventing efficient fat storage, and thus driving ectopic fat accumulation into the liver. METHODS: To identify adipose-based mechanisms and potential serum biomarker candidates (SBCs) for NAFLD, we utilise dual-tissue RNA-sequencing (RNA-seq) data in adipose tissue and liver, paired with histology-based NAFLD diagnosis, from the same individuals in a cohort of obese individuals. We first scan for genes that are differentially expressed (DE) for NAFLD in obese individuals' subcutaneous adipose tissue but not in their liver; encode proteins secreted to serum; and show preferential adipose expression. Then the identified genes are filtered to key adipose-origin NAFLD genes by best subset analysis, knockdown experiments during human preadipocyte differentiation, recombinant protein treatment experiments in human liver HepG2 cells, and genetic analysis. FINDINGS: We discover a set of genes, including 10 SBCs, that may modulate NAFLD pathogenesis by impacting adipose tissue function. Based on best subset analysis, we further follow-up on two SBCs CCDC80 and SOD3 by knockdown in human preadipocytes and subsequent differentiation experiments, which show that they modulate crucial adipogenesis genes, LPL, SREBPF1, and LEP. We also show that treatment of the liver HepG2 cells with the CCDC80 and SOD3 recombinant proteins impacts genes related to steatosis and lipid processing, including PPARA, NFE2L2, and RNF128. Finally, utilizing the adipose NAFLD DE gene cis-regulatory variants associated with serum triglycerides (TGs) in extensive genome-wide association studies (GWASs), we demonstrate a unidirectional effect of serum TGs on NAFLD with Mendelian Randomization (MR) analysis. We also demonstrate that a single SNP regulating one of the SBC genes, rs2845885, produces a significant MR result by itself. This supports the conclusion that genetically regulated adipose expression of the NAFLD DE genes may contribute to NAFLD through changes in serum TG levels. INTERPRETATION: Our results from the dual-tissue transcriptomics screening improve the understanding of obesity-related NAFLD by providing a targeted set of 10 adipose tissue-active genes as new serum biomarker candidates for the currently grossly underdiagnosed fatty liver disease. FUNDING: The work was supported by NIH grants R01HG010505 and R01DK132775. The Genotype-Tissue Expression (GTEx) Project was supported by the Common Fund of the Office of the Director of the National Institutes of Health, and by NCI, NHGRI, NHLBI, NIDA, NIMH, and NINDS. The KOBS study (J. P.) was supported by the Finnish Diabetes Research Foundation, Kuopio University Hospital Project grant (EVO/VTR grants 2005-2019), and the Academy of Finland grant (Contract no. 138006). This study was funded by the European Research Council under the European Union's Horizon 2020 research and innovation program (Grant No. 802825 to M. U. K.). K. H. P. was funded by the Academy of Finland (grant numbers 272376, 266286, 314383, and 335443), the Finnish Medical Foundation, Gyllenberg Foundation, Novo Nordisk Foundation (grant numbers NNF10OC1013354, NNF17OC0027232, and NNF20OC0060547), Finnish Diabetes Research Foundation, Finnish Foundation for Cardiovascular Research, University of Helsinki, and Helsinki University Hospital and Government Research Funds. I. S. was funded by the Instrumentarium Science Foundation. Personal grants to U. T. A. were received from the Matti and Vappu Maukonen Foundation, Ella och Georg Ehrnrooths Stiftelse and the Finnish Foundation for Cardiovascular Research.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/complicações , Estudo de Associação Genômica Ampla , Obesidade/complicações , Obesidade/genética , Obesidade/metabolismo , Fígado/metabolismo , Biomarcadores/metabolismo
10.
Epigenetics ; 17(13): 1849-1862, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35746833

RESUMO

Obesity perturbs central functions of human adipose tissue, centred on differentiation of preadipocytes to adipocytes, i.e., adipogenesis. The large environmental component of obesity makes it important to elucidate epigenetic regulatory factors impacting adipogenesis. Promoter Capture Hi-C (pCHi-C) has been used to identify chromosomal interactions between promoters and associated regulatory elements. However, long range interactions (LRIs) greater than 1 Mb are often filtered out of pCHi-C datasets, due to technical challenges and their low prevalence. To elucidate the unknown role of LRIs in adipogenesis, we investigated preadipocyte differentiation to adipocytes using pCHi-C and bulk and single nucleus RNA-seq data. We first show that LRIs are reproducible between biological replicates, and they increase >2-fold in frequency across adipogenesis. We further demonstrate that genomic loci containing LRIs are more epigenetically repressed than regions without LRIs, corresponding to lower gene expression in the LRI regions. Accordingly, as preadipocytes differentiate into adipocytes, LRI regions are more likely to contain repressed preadipocyte marker genes; whereas these same LRI regions are depleted of actively expressed adipocyte marker genes. Finally, we show that LRIs can be used to restrict multiple testing of the long-range cis-eQTL analysis to identify variants that regulate genes via LRIs. We exemplify this by identifying a putative long range cis regulatory mechanism at the LYPLAL1/TGFB2 obesity locus. In summary, we identify LRIs that mark repressed regions of the genome, and these interactions increase across adipogenesis, pinpointing developmental regions that need to be repressed in a cell-type specific way for adipogenesis to proceed.


Assuntos
Adipogenia , Metilação de DNA , Camundongos , Animais , Humanos , Adipogenia/genética , Células 3T3-L1 , Diferenciação Celular/genética , Obesidade/genética , Obesidade/metabolismo , Expressão Gênica
11.
HGG Adv ; 3(1): 100056, 2022 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-35047847

RESUMO

The prevalence of non-alcoholic fatty liver disease (NAFLD), now also known as metabolic dysfunction-associated fatty liver disease (MAFLD), is rapidly increasing worldwide due to the ongoing obesity epidemic. However, currently the NALFD diagnosis requires non-readily available imaging technologies or liver biopsy, which has drastically limited the sample sizes of NAFLD studies and hampered the discovery of its genetic component. Here we utilized the large UK Biobank (UKB) to accurately estimate the NAFLD status in UKB based on common serum traits and anthropometric measures. Scoring all individuals in UKB for NAFLD risk resulted in 28,396 NAFLD cases and 108,652 healthy individuals at a >90% confidence level. Using this imputed NAFLD status to perform the largest NAFLD genome-wide association study (GWAS) to date, we identified 94 independent (R2 < 0.2) NAFLD GWAS loci, of which 90 have not been identified before; built a polygenic risk score (PRS) model to predict the genetic risk of NAFLD; and used the GWAS variants of imputed NAFLD for a tissue-aware Mendelian randomization analysis that discovered a significant causal effect of NAFLD on coronary artery disease (CAD). In summary, we accurately estimated the NAFLD status in UKB using common serum traits and anthropometric measures, which empowered us to identify 90 GWAS NAFLD loci, build NAFLD PRS, and discover a significant causal effect of NAFLD on CAD.

12.
Opt Express ; 19(16): 14892-902, 2011 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-21934850

RESUMO

A parallel-coupled dual racetrack silicon micro-resonator structure is proposed and analyzed for M-ary quadrature amplitude modulation. The over-coupled, critically coupled, and under-coupled scenarios are systematically studied. Simulations indicate that only the over-coupled structures can generate arbitrary M-ary quadrature signals. Analytic study shows that the large dynamic range of amplitude and phase of a modulated over-coupled structure stems from the strong cross-coupling between two resonators, which can be understood through a delicate balance between the direct sum and the "interaction" terms. Potential asymmetries in the coupling constants and quality factors of the resonators are systematically studied. Compensations for these asymmetries by phase adjustment are shown feasible.

13.
Genome Med ; 13(1): 123, 2021 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-34340684

RESUMO

BACKGROUND: Obesity predisposes individuals to multiple cardiometabolic disorders, including type 2 diabetes (T2D). As body mass index (BMI) cannot reliably differentiate fat from lean mass, the metabolically detrimental abdominal obesity has been estimated using waist-hip ratio (WHR). Waist-hip ratio adjusted for body mass index (WHRadjBMI) in turn is a well-established sex-specific marker for abdominal fat and adiposity, and a predictor of adverse metabolic outcomes, such as T2D. However, the underlying genes and regulatory mechanisms orchestrating the sex differences in obesity and body fat distribution in humans are not well understood. METHODS: We searched for genetic master regulators of WHRadjBMI by employing integrative genomics approaches on human subcutaneous adipose RNA sequencing (RNA-seq) data (n ~ 1400) and WHRadjBMI GWAS data (n ~ 700,000) from the WHRadjBMI GWAS cohorts and the UK Biobank (UKB), using co-expression network, transcriptome-wide association study (TWAS), and polygenic risk score (PRS) approaches. Finally, we functionally verified our genomic results using gene knockdown experiments in a human primary cell type that is critical for adipose tissue function. RESULTS: Here, we identified an adipose gene co-expression network that contains 35 obesity GWAS genes and explains a significant amount of polygenic risk for abdominal obesity and T2D in the UKB (n = 392,551) in a sex-dependent way. We showed that this network is preserved in the adipose tissue data from the Finnish Kuopio Obesity Study and Mexican Obesity Study. The network is controlled by a novel adipose master transcription factor (TF), TBX15, a WHRadjBMI GWAS gene that regulates the network in trans. Knockdown of TBX15 in human primary preadipocytes resulted in changes in expression of 130 network genes, including the key adipose TFs, PPARG and KLF15, which were significantly impacted (FDR < 0.05), thus functionally verifying the trans regulatory effect of TBX15 on the WHRadjBMI co-expression network. CONCLUSIONS: Our study discovers a novel key function for the TBX15 TF in trans regulating an adipose co-expression network of 347 adipose, mitochondrial, and metabolically important genes, including PPARG, KLF15, PPARA, ADIPOQ, and 35 obesity GWAS genes. Thus, based on our converging genomic, transcriptional, and functional evidence, we interpret the role of TBX15 to be a main transcriptional regulator in the adipose tissue and discover its importance in human abdominal obesity.


Assuntos
Tecido Adiposo/metabolismo , Regulação da Expressão Gênica , Obesidade Abdominal/genética , Obesidade Abdominal/metabolismo , Proteínas com Domínio T/metabolismo , Transativadores/metabolismo , Adipócitos , Adiposidade/genética , Idoso , Algoritmos , Biomarcadores , Índice de Massa Corporal , Células Cultivadas , Biologia Computacional/métodos , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Suscetibilidade a Doenças , Perfilação da Expressão Gênica , Técnicas de Silenciamento de Genes , Redes Reguladoras de Genes , Estudo de Associação Genômica Ampla , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Escore Lod , Masculino , Pessoa de Meia-Idade , Relação Cintura-Quadril
14.
Opt Express ; 18(15): 16227-33, 2010 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-20721008

RESUMO

In this paper, we reported high speed optical test on polymeric optical waveguide array with embedded 45 masculine micro-mirrors on flexible substrate for out-of-plane optical interconnects. The waveguide array was bent with curvature ranging from 61 mm to 5mm. As the bending radius decreases, the average insertion loss increases from 3.4 dB to 7.7 dB for single-mode fiber (SMF) coupling and from 5.5 dB to 7.9 dB for multi-mode fiber (MMF) coupling, respectively. Eye-diagrams under such bending conditions show that the Q factor decreases from 8.0 to 6.1 and the calculated bit error rate (BER) increases from 10(-16) to 10(-10) at 10 Gbps.

15.
Opt Express ; 18(1): 378-85, 2010 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-20173857

RESUMO

In this paper, we presented fabrication of nickel based metal mold with 45 degrees tilted surfaces on both ends of the channel waveguide through electroplating process. To obtain a precise 45 degrees tilted angle, a 50microm thick SU-8 layer was UV exposed under de-ionized water, with repeatable error control of 0.5 degrees . The polymeric waveguide array with 45 degrees micro-mirrors, which is formed by a UV imprinting method with the fabricated metallic mold, shows total insertion losses around 4dB, propagation loss around 0.18dB/cm and 75% coupling efficiency.


Assuntos
Compostos de Epóxi/química , Lentes , Níquel/química , Dispositivos Ópticos , Polímeros/química , Refratometria/instrumentação , Transdutores , Desenho Assistido por Computador , Desenho de Equipamento , Análise de Falha de Equipamento , Miniaturização , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Propriedades de Superfície
16.
Nat Commun ; 11(1): 2154, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32358492

RESUMO

The past two decades have witnessed the stagnation of the clock speed of microprocessors followed by the recent faltering of Moore's law as nanofabrication technology approaches its unavoidable physical limit. Vigorous efforts from various research areas have been made to develop power-efficient and ultrafast computing machines in this post-Moore's law era. With its unique capacity to integrate complex electro-optic circuits on a single chip, integrated photonics has revolutionized the interconnects and has shown its striking potential in optical computing. Here, we propose an electronic-photonic computing architecture for a wavelength division multiplexing-based electronic-photonic arithmetic logic unit, which disentangles the exponential relationship between power and clock rate, leading to an enhancement in computation speed and power efficiency as compared to the state-of-the-art transistors-based circuits. We experimentally demonstrate its practicality by implementing a 4-bit arithmetic logic unit consisting of 8 high-speed microdisk modulators and operating at 20 GHz. This approach paves the way to future power-saving and high-speed electronic-photonic computing circuits.

17.
Nat Metab ; 1(6): 630-642, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31538139

RESUMO

Identifying gene-environment interactions (GxEs) contributing to human cardiometabolic disorders is challenging. Here we apply a reverse GxE candidate search by deriving candidate variants from promoter-enhancer interactions that respond to dietary fatty acid challenge through altered chromatin accessibility in human primary adipocytes. We then test all variants residing in the lipid-responsive open chromatin sites within adipocyte promoter-enhancer contacts for interaction effects between the genotype and dietary saturated fat intake on body mass index (BMI) in the UK Biobank. We discover 14 novel GxE variants in 12 lipid-responsive promoters, including well-known lipid genes (LIPE, CARM1, and PLIN2) and novel genes, such as LDB3, for which we provide further functional and integrative genomics evidence. We further identify 24 GxE variants in enhancers, totaling 38 new GxE variants for BMI in the UK Biobank, demonstrating that molecular genomics data produced in physiologically relevant contexts can discover new functional GxE mechanisms in humans.


Assuntos
Índice de Massa Corporal , Interação Gene-Ambiente , Células Cultivadas , Gorduras na Dieta/administração & dosagem , Humanos , Modelos Genéticos , Obesidade/genética , Obesidade/metabolismo
18.
Nat Commun ; 9(1): 3472, 2018 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-30135520

RESUMO

In the original version of this Article, Supplementary Table 10 contained incorrect primer sequences for the mobility shift assay for SNP rs4776984. These errors have now been fixed and the corrected version of the Supplementary Information PDF is available to download from the HTML version of the Article.

19.
Nat Commun ; 9(1): 1512, 2018 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-29666371

RESUMO

Increased adiposity is a hallmark of obesity and overweight, which affect 2.2 billion people world-wide. Understanding the genetic and molecular mechanisms that underlie obesity-related phenotypes can help to improve treatment options and drug development. Here we perform promoter Capture Hi-C in human adipocytes to investigate interactions between gene promoters and distal elements as a transcription-regulating mechanism contributing to these phenotypes. We find that promoter-interacting elements in human adipocytes are enriched for adipose-related transcription factor motifs, such as PPARG and CEBPB, and contribute to heritability of cis-regulated gene expression. We further intersect these data with published genome-wide association studies for BMI and BMI-related metabolic traits to identify the genes that are under genetic cis regulation in human adipocytes via chromosomal interactions. This integrative genomics approach identifies four cis-eQTL-eGene relationships associated with BMI or obesity-related traits, including rs4776984 and MAP2K5, which we further confirm by EMSA, and highlights 38 additional candidate genes.


Assuntos
Adipócitos/metabolismo , Adiposidade/genética , Cromossomos Humanos/genética , Predisposição Genética para Doença , Obesidade/genética , Tecido Adiposo/citologia , Idoso , Índice de Massa Corporal , Células Cultivadas , Estudos de Coortes , Finlândia , Regulação da Expressão Gênica/fisiologia , Biblioteca Gênica , Redes Reguladoras de Genes/fisiologia , Genômica/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/metabolismo , Fenótipo , Polimorfismo de Nucleotídeo Único , Cultura Primária de Células , Regiões Promotoras Genéticas/genética , Locos de Características Quantitativas/genética
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