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1.
ACS Sens ; 5(6): 1582-1588, 2020 06 26.
Artículo en Inglés | MEDLINE | ID: mdl-32233394

RESUMEN

In light of the importance of and challenges inherent in realizing a wearable healthcare platform for simultaneously recognizing, preventing, and treating diseases while tracking vital signs, the development of simple and customized functional devices has been required. Here, we suggest a new approach for making a stretchable light waveguide which can be combined with integrated functional devices, such as organic photodetectors (PDs) and nanowire-based heaters, for multifunctional healthcare monitoring. Controlling the reflection condition of the medium gave a solid design rule for strong light emission in our stretchable waveguides. Based on this rule, the stretchable light waveguide (up to 50% strain) made of polydimethylsiloxane was successfully demonstrated with strong emissions. We also incorporated highly sensitive organic PDs and silver nanowire-based heaters with the stretchable waveguide for the detection of vital signs, including the heart rate, deep breathing, coughs, and blood oxygen saturation. Through these multifunctional performances, we have successfully demonstrated that our stretchable light waveguide has a strong potential for multifunctional healthcare monitoring.


Asunto(s)
Nanocables , Dispositivos Electrónicos Vestibles , Plata , Signos Vitales
2.
Nat Commun ; 10(1): 1624, 2019 04 03.
Artículo en Inglés | MEDLINE | ID: mdl-30944314

RESUMEN

The original PDF version of this Article contained an error in the Additional information section, which incorrectly included the statement 'This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply 2019'. This has been removed from the PDF version of the Article. The HTML version was correct from the time of publication.

3.
Nat Commun ; 10(1): 570, 2019 02 04.
Artículo en Inglés | MEDLINE | ID: mdl-30718494

RESUMEN

Despite significant development recently, improving the power conversion efficiency of organic photovoltaics (OPVs) is still an ongoing challenge to overcome. One of the prerequisites to achieving this goal is to enable efficient charge separation and small voltage losses at the same time. In this work, a facile synthetic strategy is reported, where optoelectronic properties are delicately tuned by the introduction of electron-deficient-core-based fused structure into non-fullerene acceptors. Both devices exhibited a low voltage loss of 0.57 V and high short-circuit current density of 22.0 mA cm-2, resulting in high power conversion efficiencies of over 13.4%. These unconventional electron-deficient-core-based non-fullerene acceptors with near-infrared absorption lead to low non-radiative recombination losses in the resulting organic photovoltaics, contributing to a certified high power conversion efficiency of 12.6%.

4.
ACS Nano ; 13(2): 1071-1077, 2019 02 26.
Artículo en Inglés | MEDLINE | ID: mdl-30604955

RESUMEN

Because the visible and the infrared (IR) regions take up ∼47% and ∼51% of the energy in the solar spectrum (AM 1.5G standard), respectively, utilizing the visible light for plant growth and the IR light for power generation is potentially extremely exciting. IR-absorbing organic semiconductors, with localized IR absorption and visible-light transmittance, would be promising materials for this purpose. Here, flexible transparent organic photovoltaics (TOPVs) based on IR-absorbing organic materials were proposed, which can be a simple, low-cost, and promising way to utilize the IR light for electricity generation, and the penetrated visible light will be utilized for photosynthesis in plants. A power-conversion efficiency of ∼10% with an average visible transmittance of 34% was achieved for TOPV devices. Meanwhile, the side-by-side comparison showed that plants grown under the TOPVs filtered light, and those under normal sunlight yielded very similar results. These outcomes demonstrated the results from TOPV devices beyond simple photovoltaic applications.


Asunto(s)
Suministros de Energía Eléctrica , Compuestos Orgánicos/química , Energía Solar , Compuestos Orgánicos/síntesis química , Procesos Fotoquímicos , Fotosíntesis , Semiconductores
5.
Nano Lett ; 18(12): 7977-7984, 2018 12 12.
Artículo en Inglés | MEDLINE | ID: mdl-30475629

RESUMEN

The application of tandem structure that integrates multiple subcells into one device is a promising way to realize high efficiency organic solar cells. However, current-matching among different subcells remains as the main challenge for organic tandem photovoltaics. Here, we provide a facile approach to achieve a good current matching via engineering the chemical composition of non-fullerene ternary blend subcells. For the front subcell, a ternary blend of PDBT-T1:TPH-Se:ITIC is selected due to its good thermal stability. The amorphous nature of TPH-Se can sufficiently suppress the unfavorable phase separation of blends during the heat treatment, enabling a sintering in the fabrication of high quality interconnecting layer. A double-junction tandem device is fabricated with a rear subcell consisting of PBDB-T:ITIC. After the optimization of the chemical composition of the front subcell, the power conversion efficiency (PCE) of double-junction tandem device increased from 10.6% using PDBT-T1:TPH-Se binary front subcell to 11.5% using PDBT-T1:TPH-Se:ITIC (1:0.9:0.1) ternary front subcell due to better current matching. In order to further enhance the light absorption in the near-infrared region, a third junction PBDTTT-EFT:IEICO-4F is introduced. The champion cell of triple-junction non-fullerene tandem solar cell achieves a PCE of 13.0% with a high open circuit voltage of 2.52 V.

6.
Science ; 361(6405): 904-908, 2018 08 31.
Artículo en Inglés | MEDLINE | ID: mdl-30166487

RESUMEN

The combination of hybrid perovskite and Cu(In,Ga)Se2 (CIGS) has the potential for realizing high-efficiency thin-film tandem solar cells because of the complementary tunable bandgaps and excellent photovoltaic properties of these materials. In tandem solar device architectures, the interconnecting layer plays a critical role in determining the overall cell performance, requiring both an effective electrical connection and high optical transparency. We used nanoscale interface engineering of the CIGS surface and a heavily doped poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] (PTAA) hole transport layer between the subcells that preserves open-circuit voltage and enhances both the fill factor and short-circuit current. A monolithic perovskite/CIGS tandem solar cell achieved a 22.43% efficiency, and unencapsulated devices under ambient conditions maintained 88% of their initial efficiency after 500 hours of aging under continuous 1-sun illumination.

7.
Nano Lett ; 18(9): 5805-5811, 2018 09 12.
Artículo en Inglés | MEDLINE | ID: mdl-30075074

RESUMEN

The electron transport layer (ETL) plays an important role in determining the device efficiency of organic solar cells (OSCs). A rational design of an ETL for OSCs targets high charge extraction and induction of an optimized active layer morphology. In this Letter, a high mobility In2O3 synthesized via a solution-processed combustion reaction is successfully used as a universal ETL in an organic photovoltaic device. With the modification of a thin layer of polyethylenimine ethoxylated (PEIE), a device based on crystalline In2O3 outperforms its counterpart, ZnO, in both PBDTTT-EFT-based fullerene and nonfullerene systems. As ZnO is replaced by In2O3, the average efficiency increases from 9.5% to 10.5% for PBDTTT-EFT-PC71BM fullerene-based organic solar cells and also increases from 10.8% to 11.5% for PBDTTT-EFT-IEICO-4F nonfullerene-based organic solar cells, respectively. Morphological studies have unraveled the fact that the crystalline In2O3 ETL with highly aligned nanocrystallites has induced the crystallization of polymer into a preferential molecular packing that favors the charge transport across an active layer. From the photophysical study, it is found that charge extraction in the crystalline In2O3 device is significantly faster than in the ZnO device due to the higher mobility of In2O3 and optimized nanomorphology of the active layer.

8.
Nat Commun ; 9(1): 3021, 2018 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-30069012

RESUMEN

Compositional engineering has been used to overcome difficulties in fabricating high-quality phase-pure formamidinium perovskite films together with its ambient instability. However, this comes alongside an undesirable increase in bandgap that sacrifices the device photocurrent. Here we report the fabrication of phase-pure formamidinium-lead tri-iodide perovskite films with excellent optoelectronic quality and stability. Incorporation of 1.67 mol% of 2D phenylethylammonium lead iodide into the precursor solution enables the formation of phase-pure formamidinium perovskite with an order of magnitude enhanced photoluminescence lifetime. The 2D perovskite spontaneously forms at grain boundaries to protect the formamidinium perovskite from moisture and suppress ion migration. A stabilized power conversion efficiency (PCE) of 20.64% (certified stabilized PCE of 19.77%) is achieved with a short-circuit current density exceeding 24 mA cm-2 and an open-circuit voltage of 1.130 V, corresponding to a loss-in-potential of 0.35 V, and significantly enhanced operational stability.

9.
Adv Mater ; 30(28): e1801501, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29782685

RESUMEN

Incorporating narrow-bandgap near-infrared absorbers as the third component in a donor/acceptor binary blend is a new strategy to improve the power conversion efficiency (PCE) of organic photovoltaics (OPV). However, there are two main restrictions: potential charge recombination in the narrow-gap material and miscompatibility between each component. The optimized design is to employ a third component (structurally similar to the donor or acceptor) with a lowest unoccupied molecular orbital (LUMO) energy level similar to the acceptor and a highest occupied molecular orbital (HOMO) energy level similar to the donor. In this design, enhanced absorption of the active layer and enhanced charge transfer can be realized without breaking the optimized morphology of the active layer. Herein, in order to realize this design, two new narrow-bandgap nonfullerene acceptors with suitable energy levels and chemical structures are designed, synthesized, and employed as the third component in the donor/acceptor binary blend, which boosts the PCE of OPV to 11.6%.

10.
Adv Mater ; 30(8)2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29318665

RESUMEN

Recently, a new type of active layer with a ternary system has been developed to further enhance the performance of binary system organic photovoltaics (OPV). In the ternary OPV, almost all active layers are formed by simple ternary blend in solution, which eventually leads to the disordered bulk heterojunction (BHJ) structure after a spin-coating process. There are two main restrictions in this disordered BHJ structure to obtain higher performance OPV. One is the isolated second donor or acceptor domains. The other is the invalid metal-semiconductor contact. Herein, the concept and design of donor/acceptor/acceptor ternary OPV with more controlled structure (C-ternary) is reported. The C-ternary OPV is fabricated by a sequential solution process, in which the second acceptor and donor/acceptor binary blend are sequentially spin-coated. After the device optimization, the power conversion efficiencies (PCEs) of all OPV with C-ternary are enhanced by 14-21% relative to those with the simple ternary blend; the best PCEs are 10.7 and 11.0% for fullerene-based and fullerene-free solar cells, respectively. Moreover, the averaged PCE value of 10.4% for fullerene-free solar cell measured in this study is in great agreement with the certified one of 10.32% obtained from Newport Corporation.

11.
Nano Lett ; 17(1): 269-275, 2017 01 11.
Artículo en Inglés | MEDLINE | ID: mdl-27936782

RESUMEN

The ionic nature of perovskite photovoltaic materials makes it easy to form various chemical interactions with different functional groups. Here, we demonstrate that interfacial chemical interactions are a critical factor in determining the optoelectronic properties of perovskite solar cells. By depositing different self-assembled monolayers (SAMs), we introduce different functional groups onto the SnO2 surface to form various chemical interactions with the perovskite layer. It is observed that the perovskite solar cell device performance shows an opposite trend to that of the energy level alignment theory, which shows that chemical interactions are the predominant factor governing the interfacial optoelectronic properties. Further analysis verifies that proper interfacial interactions can significantly reduce trap state density and facilitate the interfacial charge transfer. Through use of the 4-pyridinecarboxylic acid SAM, the resulting perovskite solar cell exhibits striking improvements to the reach the highest efficiency of 18.8%, which constitutes an ∼10% enhancement compared to those without SAMs. Our work highlights the importance of chemical interactions at perovskite/electrode interfaces and paves the way for further optimizing performances of perovskite solar cells.

12.
BMC Med ; 10: 125, 2012 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-23092393

RESUMEN

BACKGROUND: Clinicians have long appreciated the distinct phenotype of systemic juvenile idiopathic arthritis (SJIA) compared to polyarticular juvenile idiopathic arthritis (POLY). We hypothesized that gene expression profiles of peripheral blood mononuclear cells (PBMC) from children with each disease would reveal distinct biological pathways when analyzed for significant associations with elevations in two markers of JIA activity, erythrocyte sedimentation rate (ESR) and number of affected joints (joint count, JC). METHODS: PBMC RNA from SJIA and POLY patients was profiled by kinetic PCR to analyze expression of 181 genes, selected for relevance to immune response pathways. Pearson correlation and Student's t-test analyses were performed to identify transcripts significantly associated with clinical parameters (ESR and JC) in SJIA or POLY samples. These transcripts were used to find related biological pathways. RESULTS: Combining Pearson and t-test analyses, we found 91 ESR-related and 92 JC-related genes in SJIA. For POLY, 20 ESR-related and 0 JC-related genes were found. Using Ingenuity Systems Pathways Analysis, we identified SJIA ESR-related and JC-related pathways. The two sets of pathways are strongly correlated. In contrast, there is a weaker correlation between SJIA and POLY ESR-related pathways. Notably, distinct biological processes were found to correlate with JC in samples from the earlier systemic plus arthritic phase (SAF) of SJIA compared to samples from the later arthritis-predominant phase (AF). Within the SJIA SAF group, IL-10 expression was related to JC, whereas lack of IL-4 appeared to characterize the chronic arthritis (AF) subgroup. CONCLUSIONS: The strong correlation between pathways implicated in elevations of both ESR and JC in SJIA argues that the systemic and arthritic components of the disease are related mechanistically. Inflammatory pathways in SJIA are distinct from those in POLY course JIA, consistent with differences in clinically appreciated target organs. The limited number of ESR-related SJIA genes that also are associated with elevations of ESR in POLY implies that the SJIA associations are specific for SJIA, at least to some degree. The distinct pathways associated with arthritis in early and late SJIA raise the possibility that different immunobiology underlies arthritis over the course of SJIA.


Asunto(s)
Artritis Juvenil/patología , Patología Molecular , Sedimentación Sanguínea , Niño , Preescolar , Femenino , Perfilación de la Expresión Génica , Humanos , Articulaciones/patología , Leucocitos Mononucleares/inmunología , Masculino
13.
Clin Immunol ; 142(3): 362-72, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22281427

RESUMEN

Systemic juvenile idiopathic arthritis (SJIA) is a chronic autoinflammatory condition. The association with macrophage activation syndrome, and the therapeutic efficacy of inhibiting monocyte-derived cytokines, has implicated these cells in SJIA pathogenesis. To characterize the activation state (classical/M1 vs. alternative/M2) of SJIA monocytes, we immunophenotyped monocytes using several approaches. Monocyte transcripts were analyzed by microarray and quantitative PCR. Surface proteins were measured at the single cell level using flow cytometry. Cytokine production was evaluated by intracellular staining and ELISA. CD14(++)CD16(-) and CD14(+)CD16(+) monocyte subsets are activated in SJIA. A mixed M1/M2 activation phenotype is apparent at the single cell level, especially during flare. Consistent with an M2 phenotype, SJIA monocytes produce IL-1ß after LPS exposure, but do not secrete it. Despite the inflammatory nature of active SJIA, circulating monocytes demonstrate significant anti-inflammatory features. The persistence of some of these phenotypes during clinically inactive disease argues that this state reflects compensated inflammation.


Asunto(s)
Artritis Juvenil/inmunología , Monocitos/inmunología , Células Cultivadas , Niño , Citocinas/biosíntesis , Citocinas/inmunología , Proteínas Ligadas a GPI/inmunología , Expresión Génica , Humanos , Receptores de Lipopolisacáridos/inmunología , Fenotipo , Receptores de IgG/inmunología
14.
Clin Immunol ; 136(2): 257-68, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20462799

RESUMEN

We investigated whether circulating monocytes from patients with systemic juvenile idiopathic arthritis (SJIA) are resistant to apoptosis and which apoptotic pathway(s) may mediate this resistance. A microarray analysis of peripheral blood mononuclear cells (PBMC) of SJIA samples and RT-PCR analysis of isolated monocytes showed that monocytes from active SJIA patients express transcripts that imply resistance to apoptosis. SJIA monocytes incubated in low serum show reduced annexin binding and diminished FasL up-regulation compared to controls. SJIA monocytes are less susceptible to anti-Fas-induced apoptosis and, upon activation of the mitochondrial pathway with staurosporine, show diminished Bid cleavage and Bcl-w down-regulation compared to controls. Exposure to SJIA plasma reduces responses to apoptotic triggers in normal monocytes. Thus, SJIA monocytes are resistant to apoptosis due to alterations in both the extrinsic and intrinsic apoptosis pathways, and circulating factors associated with active SJIA may confer this phenotype.


Asunto(s)
Apoptosis/fisiología , Artritis Juvenil/fisiopatología , Monocitos/fisiología , Adolescente , Anticuerpos/inmunología , Apoptosis/genética , Artritis Juvenil/sangre , Supervivencia Celular , Células Cultivadas , Niño , Proteína Ligando Fas/metabolismo , Perfilación de la Expresión Génica , Regulación de la Expresión Génica/fisiología , Humanos , Mitocondrias/metabolismo , Monocitos/citología , Receptor fas/inmunología
15.
Cancer Res ; 69(12): 5049-56, 2009 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-19491269

RESUMEN

Clinical and animal studies have shown that coexpression of the receptor tyrosine kinases HER2 and epidermal growth factor (EGF) receptor (EGFR) indicates a highly metastatic phenotype of breast cancer. In a cellular model of this phenotype using differential gene expression analysis, we identified TOB1 to be up-regulated depending on EGF stimulation and transduction through phosphorylation of HER2 tyrosine 1248. mRNA expression analysis of breast cancers from a cohort of node-negative patients showed significantly shortened distant metastasis-free survival for patients with high TOB1 expression. In subsequent tissue microarray studies of 725 clinical samples, high HER2 and EGF protein levels were significantly correlated with TOB1 expression in breast cancer, whereas EGFR and EGF levels correlated with TOB1 phosphorylation. We did not observe a correlation between TOB1 expression and cyclin D1, which was previously suggested to mediate the antiproliferative effect of unphosphorylated TOB1. A positive correlation of TOB1 phosphorylation status with proliferation marker Ki67 suggests that elevated TOB1 phosphorylation might abrogate the antiproliferative effect of TOB1 in breast cancer. This suggests a new regulatory role for TOB1 in cancer progression with particular significance in HER2- and/or EGFR-positive breast cancers.


Asunto(s)
Neoplasias de la Mama/metabolismo , Factor de Crecimiento Epidérmico/metabolismo , Receptores ErbB/metabolismo , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Receptor ErbB-2/metabolismo , Transducción de Señal , Proteínas Supresoras de Tumor/metabolismo , Western Blotting , Neoplasias de la Mama/patología , Señalización del Calcio , Línea Celular Tumoral , Proliferación Celular , Humanos , Inmunohistoquímica , Péptidos y Proteínas de Señalización Intracelular/genética , Fosforilación , Pronóstico , ARN Mensajero/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Proteínas Supresoras de Tumor/genética , Regulación hacia Arriba
16.
J Mol Diagn ; 11(2): 117-30, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19225135

RESUMEN

Knowledge of estrogen receptor (ER) and progesterone receptor (PR) status has been critical in the evolution of modern targeted therapy of breast cancer and remains essential for making informed therapeutic decisions. Recently, growth factor receptor HER2/neu (ERBB2) status has made it possible to provide another form of targeted therapy linked to the overexpression of this protein. Presently, pathologists determine the receptor status in formalin-fixed, paraffin-embedded sections using subjective, semiquantitative immunohistochemistry (IHC) assays and quantitative fluorescence in situ hybridization for HER2. We developed a single-tube multiplex TaqMan (mERPR+HER2) assay to quantitate mRNA levels of ER, PR, HER2, and two housekeeping genes for breast cancer formalin-fixed, paraffin-embedded sections. Using data from the discovery sample sets, we evaluated IHC-status-dependent cutoff-point and IHC-status-independent clustering methods for the classification of receptor status and then validated these results with independent sample sets. Compared with IHC-status, the accuracies of the mERPR+HER2 assay with the cutoff-point classification method were 0.98 (95% CI: 0.97-1.00), 0.92 (95% CI: 0.88-0.95), and 0.97 (95% CI: 0.95-0.99) for ER, PR, and HER2, respectively, for the validation sets. Furthermore, the areas under the receiver operating-characteristic curves were 0.997 (95% CI: 0.994-1.000), 0.967 (95% CI: 0.949-0.985), and 0.968 (95% CI: 0.915-1.000) for ER, PR, and HER2, respectively. This multiplex assay provides a sensitive and reliable method to quantitate hormonal and growth factor receptors.


Asunto(s)
Neoplasias de la Mama/diagnóstico , Técnicas de Diagnóstico Molecular/métodos , ARN Mensajero/análisis , Receptor ErbB-2/genética , Receptores de Estrógenos/genética , Receptores de Progesterona/genética , Femenino , Formaldehído/química , Humanos , Adhesión en Parafina , ARN Mensajero/genética , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Fijación del Tejido , Regulación hacia Arriba
17.
Hepatology ; 49(3): 763-74, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19140155

RESUMEN

UNLABELLED: Responsiveness to hepatitis C virus (HCV) therapy depends on viral and host factors. Our aim was to assess sustained virologic response (SVR)-associated early gene expression in patients with HCV receiving pegylated interferon-alpha2a (PEG-IFN-alpha2a) or PEG-IFN-alpha2b and ribavirin with the duration based on genotypes. Blood samples were collected into PAXgene tubes prior to treatment as well as 1, 7, 28, and 56 days after treatment. From the peripheral blood cells, total RNA was extracted, quantified, and used for one-step reverse transcription polymerase chain reaction to profile 154 messenger RNAs. Expression levels of messenger RNAs were normalized with six "housekeeping" genes and a reference RNA. Multiple regression and stepwise selection were performed to assess differences in gene expression at different time points, and predictive performance was evaluated for each model. A total of 68 patients were enrolled in the study and treated with combination therapy. The results of gene expression showed that SVR could be predicted by the gene expression of signal transducer and activator of transcription-6 (STAT-6) and suppressor of cytokine signaling-1 in the pretreatment samples. After 24 hours, SVR was predicted by the expression of interferon-dependent genes, and this dependence continued to be prominent throughout the treatment. CONCLUSION: Early gene expression during anti-HCV therapy may elucidate important molecular pathways that may be influencing the probability of achieving virologic response.


Asunto(s)
Antivirales/uso terapéutico , Perfilación de la Expresión Génica , Hepatitis C Crónica/tratamiento farmacológico , Hepatitis C Crónica/metabolismo , Interferón-alfa/uso terapéutico , Polietilenglicoles/uso terapéutico , Ribavirina/uso terapéutico , Adulto , Antivirales/farmacología , Quimiocina CCL3/genética , Quimiocina CCL3/metabolismo , Quimioterapia Combinada , Femenino , Hepacivirus/efectos de los fármacos , Hepacivirus/fisiología , Hepatitis C Crónica/genética , Humanos , Factor 2 Regulador del Interferón/genética , Factor 2 Regulador del Interferón/metabolismo , Interferón alfa-2 , Interferón-alfa/farmacología , Masculino , Persona de Mediana Edad , Modelos Biológicos , Modelos Genéticos , Proyectos Piloto , Polietilenglicoles/farmacología , Valor Predictivo de las Pruebas , ARN Mensajero/metabolismo , Proteínas Recombinantes , Ribavirina/farmacología , Factor de Transcripción STAT5/genética , Factor de Transcripción STAT5/metabolismo , Factor de Transcripción STAT6/genética , Factor de Transcripción STAT6/metabolismo , Proteínas Supresoras de Tumor/genética , Proteínas Supresoras de Tumor/metabolismo
18.
Proc Natl Acad Sci U S A ; 101(44): 15688-93, 2004 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-15507493

RESUMEN

Although several genes have been implicated in the development of the early-onset autosomal dominant form of Alzheimer's disease (AD), the genetics of late-onset AD (LOAD) is complex. Loci on several chromosomes have been linked to the disease, but so far only the apolipoprotein E gene has been consistently shown to be a risk factor. We have performed a large-scale single-nucleotide polymorphism (SNP)-based association study, across the region of linkage on chromosome 12, in multiple case-control series totaling 1,089 LOAD patients and 1,196 control subjects and report association with SNPs in the glyceraldehyde-3-phosphate dehydrogenase (GAPD) gene. Subsequent analysis of GAPD paralogs on other chromosomes demonstrated association with two other paralogs. A significant association between LOAD and a compound genotype of the three GAPD genes was observed in all three sample sets. Individually, these SNPs make differential contributions to disease risk in each of the casecontrol series, suggesting that variants in functionally similar genes may account for series-to-series heterogeneity of disease risk. Our observations raise the possibility that GAPD genes are AD risk factors, a hypothesis that is consistent with the role of GAPD in neuronal apoptosis.


Asunto(s)
Enfermedad de Alzheimer/enzimología , Enfermedad de Alzheimer/genética , Gliceraldehído-3-Fosfato Deshidrogenasas/genética , Edad de Inicio , Anciano , Alelos , Enfermedad de Alzheimer/etiología , Apolipoproteína E4 , Apolipoproteínas E/genética , Apoptosis , Encéfalo/enzimología , Estudios de Casos y Controles , Cromosomas Humanos Par 12/genética , Expresión Génica , Frecuencia de los Genes , Variación Genética , Genotipo , Humanos , Persona de Mediana Edad , Familia de Multigenes , Degeneración Nerviosa , Polimorfismo de Nucleótido Simple , Factores de Riesgo
19.
Am J Hum Genet ; 75(2): 330-7, 2004 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-15208781

RESUMEN

Rheumatoid arthritis (RA) is the most common systemic autoimmune disease, affecting approximately 1% of the adult population worldwide, with an estimated heritability of 60%. To identify genes involved in RA susceptibility, we investigated the association between putative functional single-nucleotide polymorphisms (SNPs) and RA among white individuals by use of a case-control study design; a second sample was tested for replication. Here we report the association of RA susceptibility with the minor allele of a missense SNP in PTPN22 (discovery-study allelic P=6.6 x 10(-4); replication-study allelic P=5.6 x 10(-8)), which encodes a hematopoietic-specific protein tyrosine phosphatase also known as "Lyp." We show that the risk allele, which is present in approximately 17% of white individuals from the general population and in approximately 28% of white individuals with RA, disrupts the P1 proline-rich motif that is important for interaction with Csk, potentially altering these proteins' normal function as negative regulators of T-cell activation. The minor allele of this SNP recently was implicated in type 1 diabetes, suggesting that the variant phosphatase may increase overall reactivity of the immune system and may heighten an individual carrier's risk for autoimmune disease.


Asunto(s)
Artritis Reumatoide/genética , Mutación Missense , Polimorfismo de Nucleótido Simple , Proteínas Tirosina Fosfatasas/genética , Frecuencia de los Genes , Humanos , Datos de Secuencia Molecular , Especificidad de Órganos/fisiología , Proteína Tirosina Fosfatasa no Receptora Tipo 1 , ARN Mensajero/fisiología
20.
J Rheumatol ; 30(7): 1611-5, 2003 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12858466

RESUMEN

OBJECTIVE: The mechanisms controlling the recruitment of T helper type 1 (Th1) cells to the inflamed synovium are not fully understood. Here, we focus on alpha(1,3)-fucosyltransferase-VII (FucT-VII), an enzyme responsible for the generation of functional P- and E-selectin ligands that is upregulated in Th1 cells. METHODS: Expression of transcripts encoding FucT-VII, interferon-gamma (IFN-gamma), and interleukin 12Rbeta2 (IL-12Rbeta2) were analyzed in T cells purified from synovial fluid (SF) and from peripheral blood (PB) of children with juvenile idiopathic arthritis (JIA) using kinetic reverse transcriptase polymerase chain reaction analysis. Binding of SF and PB T cells to P-selectin was determined by flow cytometry using a soluble P-selectin/IgG1 fusion molecule. Recruitment of T cells to synovial tissue in vivo was studied by analyzing the migration of FucT-VII transfected Jurkat T cells into human rheumatoid synovial tissue grafted into SCID mice. RESULTS: In patients with JIA, the mRNA levels of FucT-VII, as well as of IFN-gamma and IL-12Rbeta2, were up-regulated in SF T cells compared to paired PB T cells. A higher expression of FucT-VII mRNA in SF T cells was associated with increased binding of T cells to P-selectin. Moreover, FucT-VII expression and increased P-selectin binding capacity of T cells were associated with a polyarticular course of oligoarticular JIA. Expression of FucT-VII in Jurkat T cells resulted in an increased accumulation of these cells in human rheumatoid synovial tissue grafted into SCID mice. CONCLUSION: Our data indicate an important role of FucT-VII in the enhanced homing of T cells to the inflamed synovium.


Asunto(s)
Artritis Juvenil/metabolismo , Fucosiltransferasas/metabolismo , Selectina-P/metabolismo , Linfocitos T/enzimología , Adolescente , Adulto , Animales , Células Cultivadas , Niño , Preescolar , Citometría de Flujo , Fucosiltransferasas/genética , Humanos , Lactante , Interferón gamma/genética , Interferón gamma/metabolismo , Células Jurkat , Ratones , Ratones SCID , Selectina-P/genética , ARN Mensajero/metabolismo , Receptores de Interleucina/genética , Receptores de Interleucina/metabolismo , Receptores de Interleucina-12 , Líquido Sinovial/citología , Líquido Sinovial/enzimología , Membrana Sinovial/metabolismo , Membrana Sinovial/patología , Membrana Sinovial/trasplante , Linfocitos T/patología , Transfección , Regulación hacia Arriba
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