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1.
Nature ; 611(7934): 48-54, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36224392

RESUMEN

Optical vortices are beams of light that carry orbital angular momentum1, which represents an extra degree of freedom that can be generated and manipulated for photonic applications2-8. Unlike vortices in other physical entities, the generation of optical vortices requires structural singularities9-12, but this affects their quasiparticle nature and hampers the possibility of altering their dynamics or making them interacting13-17. Here we report a platform that allows the spontaneous generation and active manipulation of an optical vortex-antivortex pair using an external field. An aluminium/silicon dioxide/nickel/silicon dioxide multilayer structure realizes a gradient-thickness optical cavity, where the magneto-optic effects of the nickel layer affect the transition between a trivial and a non-trivial topological phase. Rather than a structural singularity, the vortex-antivortex pairs present in the light reflected by our device are generated through mathematical singularities in the generalized parameter space of the top and bottom silicon dioxide layers, which can be mapped onto real space and exhibit polarization-dependent and topology-dependent dynamics driven by external magnetic fields. We expect that the field-induced engineering of optical vortices that we report will facilitate the study of topological photonic interactions and inspire further efforts to bestow quasiparticle-like properties to various topological photonic textures such as toroidal vortices, polarization and vortex knots, and optical skyrmions.

2.
Nano Lett ; 23(6): 2158-2165, 2023 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-36854053

RESUMEN

Embodying bosonic and interactive characteristics in two-dimensional space, excitons in transition metal dichalcogenides (TMDCs) have garnered considerable attention. The utilization of the strong-correlation effects, long-range transport, and valley-dependent properties requires customizing exciton decay dynamics. Vacuum-field manipulation allows radiative decay engineering without disturbing intrinsic material properties. However, conventional flat mirrors cannot customize the radiative decay landscape in TMDC's plane or support vacuum-field interference with desired spectrum and polarization properties. Here, we present a meta-mirror platform resolving the issues with more optical degrees of freedom. For neutral excitons of the monolayer MoSe2, the optical layout formed by meta-mirrors manipulated the radiative decay rate in space by 2 orders of magnitude and revealed the statistical correlation between emission intensity and spectral line width. Moreover, the anisotropic meta-mirror demonstrated polarization-dependent radiative decay control. Our platform would be promising to tailor two-dimensional distributions of lifetime, density, diffusion, and polarization of TMDC excitons in advanced opto-excitonic applications.

3.
J Chem Educ ; 100(8): 3138-3143, 2023 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-37577455

RESUMEN

Sanger sequencing, also known as dideoxy sequencing, is a widely used method for DNA sequencing, particularly for cloned plasmids and clinical samples. This technique requires a combination of essential biochemistry skills, such as a chain-termination reaction, gel electrophoresis, and fluorescence detection. Unfortunately, there is a lack of activities that replicate the Sanger sequencing process for students to learn and practice these skills. To address this issue, a manipulative-based Sanger sequencing activity was developed that incorporates colorful pop beads to demonstrate a chain-termination reaction, separation of products, and fluorescence detection. The beads represent deoxynucleotides and dideoxynucleotides, allowing for a visual representation of DNA fragment generation. This kinesthetic learning activity offers a high visual impact for students, aiding in their understanding of the Sanger sequencing process, and can also be used to illustrate polymerase chain reaction (PCR)-based techniques.

4.
Lancet ; 398(10308): 1305-1316, 2021 10 09.
Artículo en Inglés | MEDLINE | ID: mdl-34627490

RESUMEN

BACKGROUND: In patients with acute myocardial infarction receiving potent antiplatelet therapy, the bleeding risk remains high during the maintenance phase. We sought data on a uniform unguided de-escalation strategy of dual antiplatelet therapy (DAPT) from ticagrelor to clopidogrel after acute myocardial infarction. METHODS: In this open-label, assessor-masked, multicentre, non-inferiority, randomised trial (TALOS-AMI), patients at 32 institutes in South Korea with acute myocardial infarction receiving aspirin and ticagrelor without major ischaemic or bleeding events during the first month after index percutaneous coronary intervention (PCI) were randomly assigned in a 1:1 ratio to a de-escalation (clopidogrel plus aspirin) or active control (ticagrelor plus aspirin) group. Unguided de-escalation without a loading dose of clopidogrel was adopted when switching from ticagrelor to clopidogrel. The primary endpoint was a composite of cardiovascular death, myocardial infarction, stroke, or bleeding type 2, 3, or 5 according to Bleeding Academic Research Consortium (BARC) criteria from 1 to 12 months. A non-inferiority test was done to assess the safety and efficacy of de-escalation DAPT compared with standard treatment. The hazard ratio (HR) for de-escalation versus active control group in a stratified Cox proportional hazards model was assessed for non-inferiority by means of an HR margin of 1·34, which equates to an absolute difference of 3·0% in the intention-to-treat population and, if significant, a superiority test was done subsequently. To ensure statistical robustness, additional analyses were also done in the per-protocol population. This trial is registered at ClinicalTrials.gov, NCT02018055. FINDINGS: From Feb 26, 2014, to Dec 31, 2018, from 2901 patients screened, 2697 patients were randomly assigned: 1349 patients to de-escalation and 1348 to active control groups. At 12 months, the primary endpoints occurred in 59 (4·6%) in the de-escalation group and 104 (8·2%) patients in the active control group (pnon-inferiority<0·001; HR 0·55 [95% CI 0·40-0·76], psuperiority=0·0001). There was no significant difference in composite of cardiovascular death, myocardial infarction, or stroke between de-escalation (2·1%) and the active control group (3·1%; HR 0·69; 95% CI 0·42-1·14, p=0·15). Composite of BARC 2, 3, or 5 bleeding occurred less frequently in the de-escalation group (3·0% vs 5·6%, HR 0·52; 95% CI 0·35-0·77, p=0·0012). INTERPRETATION: In stabilised patients with acute myocardial infarction after index PCI, a uniform unguided de-escalation strategy significantly reduced the risk of net clinical events up to 12 months, mainly by reducing the bleeding events. FUNDING: ChongKunDang Pharm, Medtronic, Abbott, and Boston Scientific.


Asunto(s)
Clopidogrel/administración & dosificación , Terapia Antiplaquetaria Doble/métodos , Infarto del Miocardio/tratamiento farmacológico , Ticagrelor/administración & dosificación , Anciano , Aspirina/administración & dosificación , Clopidogrel/efectos adversos , Femenino , Hemorragia/inducido químicamente , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/mortalidad , Infarto del Miocardio/cirugía , Intervención Coronaria Percutánea , República de Corea , Accidente Cerebrovascular , Ticagrelor/efectos adversos , Resultado del Tratamiento
5.
Nat Methods ; 16(8): 771-777, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31308549

RESUMEN

Ubiquitin (Ub) conjugation is an essential post-translational modification that affects nearly all proteins in eukaryotes. The functions and mechanisms of ubiquitination are areas of extensive study, and yet the dynamics and regulation of even free (that is, unconjugated) Ub are poorly understood. A major impediment has been the lack of simple and robust techniques to quantify Ub levels in cells and to monitor Ub release from conjugates. Here, we describe avidity-based fluorescent sensors that address this need. The sensors bind specifically to free Ub, have dissociation constant Kd values down to 60 pM and, together with a newly developed workflow, allow us to distinguish and quantify the pools of free, protein-conjugated and thioesterified forms of Ub from cell lysates. Alternatively, free Ub in fixed cells can be visualized microscopically by staining with a sensor. Real-time assays using the sensors afford unprecedented flexibility and precision to measure deubiquitination of virtually any (poly)Ub conjugate.


Asunto(s)
Técnicas Biosensibles , Homeostasis , Procesamiento Proteico-Postraduccional , Proteínas/metabolismo , Ubiquitina/metabolismo , Ubiquitinación , Células HeLa , Humanos , Unión Proteica , Conformación Proteica , Proteínas/química
6.
Acta Radiol ; 62(10): 1349-1357, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33070634

RESUMEN

BACKGROUND: Tin filter-based spectral shaping has been used for low-dose and ultra-low-dose computed tomography (CT) in several body parts. However, studies of shoulder CT arthrography with spectral shaping are limited. PURPOSE: To investigate image quality and radiation dose of shoulder CT arthrography with tin filter-based spectral shaping at 100 kV (Sn 100 kV) and 140 kV (Sn 140 kV) in comparison with the conventional protocol. MATERIAL AND METHODS: Ninety-nine shoulder CT arthrographies with protocols of Sn 100 kV (n = 32), Sn 140 kV (n = 25), and conventional 120 kV (n = 42) were retrospectively evaluated. Qualitative image quality, CT attenuations of intra-articular contrast mixture and tissues, background noise, contrast-to-noise ratios (CNRs), and figures of merit were assessed. Radiation doses were compared. RESULTS: CT arthrographies with Sn 100 kV and Sn 140 kV yielded approximately 70% and 60% radiation dose reduction, respectively, compared with the conventional 120 kV (P < 0.001). Qualitative image noise and quantitative background noise of Sn 100 kV and Sn 140 kV were significantly less than those of the conventional protocol. Qualitative image contrast, CT attenuations of intra-articular contrast mixture and tissues, and CNRs for Sn 100 were similar to those of the conventional 120 kV. However, Sn 140 kV showed significantly lower qualitative contrast and CNRs than 120 kV. Sn 100 kV was the most dose efficient among the three protocols. CONCLUSION: Shoulder CT arthrography with Sn 100 kV substantially reduced radiation dose and image noise and maintained image contrast, compared with the conventional protocol.


Asunto(s)
Artrografía/métodos , Dosis de Radiación , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Articulación del Hombro/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Estudios Retrospectivos , Estaño
7.
Knee Surg Sports Traumatol Arthrosc ; 28(3): 941-951, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31240378

RESUMEN

PURPOSE: To investigate the clinical, radiological, and histological results of arthroscopic gel-type autologous chondrocyte implantation (GACI) in treating chondral defects of the knee. METHODS: This study prospectively examined five males and five females with a mean age of 40.3 ± 10.3 years who underwent arthroscopic GACI between March 2012 and February 2013. The gel comprised a mixture of 1 ml of fibrinogen plus 0.1-0.2 ml of thrombin. The mean size of chondral defect was 2.9 ± 1.2 cm2 (range 1.2-5.4 cm2). International knee documentation committee (IKDC) subjective score, knee injury and osteoarthritis outcome score (KOOS), knee society score, and visual analog scale (VAS) for pain were assessed preoperatively and during regular follow-up examinations performed for up to 5 years postoperatively. Serial magnetic resonance imaging was performed for up to 2 years after the surgery to observe healing, using the modified magnetic resonance observation of cartilage repair tissue (MOCART) score. In eight patients, second-look arthroscopy was performed at 1 year after the implantation to assess the status of treated cartilage, and a portion of regenerated cartilage was harvested for histologic evaluation. RESULTS: The mean VAS score (p = 0.045), IKDC subjective score (p = 0.041), KOOS pain (p = 0.025), KOOS activities of daily living (p = 0.048), and KOOS quality of life (p = 0.029) showed significant improvement at 5 years after the surgery. The modified MOCART evaluation showed that the scores were 59.5 ± 29.4 and 85.0 ± 8.0 at 12 weeks and 2 years after the operation, respectively. Histologic examination demonstrated a mean regenerated cartilage thickness of 3.5 ± 0.8 mm and a mean Oswestry score of 8.2 ± 1.8. Immunohistochemistry analysis showed that the expression of collagen type II was more evident and more evenly distributed than collagen type I in regenerated cartilage. There was a significant correlation between Oswestry score and change in VAS scale from postoperative 2-5 years. CONCLUSIONS: Arthroscopic GACI produces satisfactory clinical and radiologic outcomes, and histologic evaluation confirms sufficient regeneration of hyaline-like cartilage that correlates with improved symptoms. Therefore, it is an acceptable, minimally invasive, and technically simple option for the restoration of cartilage defects of the knee. LEVEL OF EVIDENCE: IV.


Asunto(s)
Artroscopía/métodos , Enfermedades de los Cartílagos/cirugía , Cartílago Articular/fisiología , Cartílago Articular/cirugía , Condrocitos/trasplante , Articulación de la Rodilla/fisiología , Articulación de la Rodilla/cirugía , Actividades Cotidianas , Adulto , Enfermedades de los Cartílagos/diagnóstico por imagen , Cartílago Articular/diagnóstico por imagen , Femenino , Estudios de Seguimiento , Humanos , Hialina/fisiología , Articulación de la Rodilla/diagnóstico por imagen , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Calidad de Vida , Regeneración , Segunda Cirugía , Trasplante Autólogo , Escala Visual Analógica
8.
Circulation ; 135(3): 251-263, 2017 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-27831500

RESUMEN

BACKGROUND: The relationship of LPA single nucleotide polymorphisms (SNPs), apolipoprotein(a) isoforms, and lipoprotein(a) [Lp(a)] levels with major adverse cardiovascular events (MACE) in different ethnic groups is not well known. METHODS: LPA SNPs, apolipoprotein(a) isoforms, Lp(a), and oxidized phospholipids on apolipoprotein B-100 (OxPL-apoB) levels were measured in 1792 black, 1030 white, and 597 Hispanic subjects enrolled in the Dallas Heart Study. Their interdependent relationships and prospective association with MACE after median 9.5-year follow-up were determined. RESULTS: LPA SNP rs3798220 was most prevalent in Hispanics (42.38%), rs10455872 in whites (14.27%), and rs9457951 in blacks (32.92%). The correlation of each of these SNPs with the major apolipoprotein(a) isoform size was highly variable and in different directions among ethnic groups. In the entire cohort, Cox regression analysis with multivariable adjustment revealed that quartiles 4 of Lp(a) and OxPL-apoB were associated with hazard ratios (95% confidence interval) for time to MACE of 2.35 (1.50-3.69, P<0.001) and 1.89 (1.26-2.84, P=0.003), respectively, versus quartile 1. Addition of the major apolipoprotein(a) isoform and the 3 LPA SNPs to these models attenuated the risk, but significance was maintained for both Lp(a) and OxPL-apoB. Evaluating time to MACE in specific ethnic groups, Lp(a) was a positive predictor and the size of the major apolipoprotein(a) isoform was an inverse predictor in blacks, the size of the major apolipoprotein(a) isoform was an inverse predictor in whites, and OxPL-apoB was a positive predictor in Hispanics. CONCLUSIONS: The prevalence and association of LPA SNPs with size of apolipoprotein(a) isoforms, Lp(a), and OxPL-apoB levels are highly variable and ethnicity-specific. The relationship to MACE is best explained by elevated plasma Lp(a) or OxPL-apoB levels, despite significant ethnic differences in LPA genetic markers.


Asunto(s)
Enfermedades Cardiovasculares/sangre , Lipoproteína(a)/sangre , Polimorfismo de Nucleótido Simple/genética , Adulto , Etnicidad , Femenino , Humanos , Masculino , Estudios Prospectivos , Factores de Riesgo
9.
Small ; 14(43): e1702985, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29280277

RESUMEN

Nanostructured materials make a considerable impact on the performance of lithium-storage characteristics in terms of the energy density, power density, and cycle life. Direct experimental observation, by a comparison of controlled nanostructural uniformity of electrode materials, reveals that the lithium-storage behaviors of mesoporous MoO2 and CuO electrodes are linearly correlated with their nanostructural uniformity. Reversible capacities of mesoporous MoO2 and CuO electrodes with well-developed nanostructures (1569 mA h g-1 for MoO2 and 1029 mA h g-1 for CuO) exceed their theoretical capacity based on the conversion reaction (838 mA h g-1 for MoO2 and 674 mA h g-1 for CuO). Given that exact understanding of the origin of the additional capacity is essential in maximizing the energy density of electrode material, this work may help to gain some insights into the development of high energy-density lithium-storage materials for next-generation lithium rechargeable batteries.

10.
Lipids Health Dis ; 16(1): 172, 2017 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-28899385

RESUMEN

BACKGROUND: The purpose of this study was to describe and analyze the relationship between statin benefit groups based on statin-intensity class of drugs and coronary artery calcium score (CACS) using multidetector computed tomography (MDCT) in an asymptomatic Korean population. METHODS: A total of 3914 asymptomatic individuals (mean age: 55 ± 10 years; male: female = 2649: 1265) who underwent MDCT for health examination between January 2009 and December 2012 were retrospectively enrolled. They were categorized into three groups based on statin-intensity class of drugs (high-intensity (n = 1284, 32.8%); moderate-intensity (n = 1602, 40.9%) and low-intensity (n = 931, 23.8%) statin therapy groups) according to the American College of Cardiology (ACC)/American heart Association (AHA) 2013 guideline and the relationship between CACS and statin benefit group was analyzed. The statin benefit group was defined as individuals who should be considered moderate- and high-intensity statin therapy. RESULTS: Ten-year atherosclerotic cardiovascular disease (ASCVD; 12.6 ± 5.3% vs. 2.9 ± 1.9%, p < 0.001) and CACS (98 ± 270 vs. 3 ± 2, p < 0.001) were significantly higher in the high-intensity group compared to the moderate-intensity statin therapy group. In the high-intensity statin therapy group, age [odds ratio: 1.299 (1.137-1.483), p < 0.001], male gender [odds ratio: 44.252 (1.959-999.784), p = 0.001], and fasting blood glucose [odds ratio: 1.046 (1.007-1.087), p = 0.021] were independent risk factors associated with CACS ≥300 on multivariate logistic regression analysis. CONCLUSIONS: CACS on MDCT might be an important complementary tool for cardiovascular disease risk stratification. This study indicates that individualization of statin therapy as well as lifestyle modification will be useful in asymptomatic individuals, especially those in whom high-intensity statin therapy is required.


Asunto(s)
Calcio/metabolismo , Enfermedades Cardiovasculares/diagnóstico por imagen , Vasos Coronarios/metabolismo , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Anciano , Aterosclerosis/etiología , Aterosclerosis/prevención & control , Enfermedades Cardiovasculares/etiología , Enfermedades Cardiovasculares/prevención & control , Vasos Coronarios/diagnóstico por imagen , Femenino , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/farmacología , Modelos Logísticos , Masculino , Persona de Mediana Edad , Tomografía Computarizada Multidetector/métodos , Factores de Riesgo
11.
J Lipid Res ; 57(4): 706-13, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26848137

RESUMEN

Elevated apoC-III levels predict increased cardiovascular risk when present on LDL and HDL particles. We developed novel high-throughput chemiluminescent ELISAs that capture apoB, lipoprotein (a) [Lp(a)], and apoA-I in plasma and then detect apoC-III on these individual lipoproteins as apoCIII-apoB, apoCIII-Lp(a), and apoCIII-apoAI complexes, respectively. We assessed the effects on these complexes of placebo or 100-300 mg volanesorsen, a generation 2.0+ antisense drug that targets apoC3 mRNA in patients with hypertriglyceridemia, including familial chylomicronemia syndrome (n = 3), volanesorsen monotherapy (n = 51), and as add-on to fibrate (n = 26), treated for 85 days and followed for 176 days. Compared with placebo, volanesorsen was associated with an 82.3 ± 11.7%, 81.3 ± 15.7%, and 80.8 ± 13.6% reduction in apoCIII-apoB, apoCIII-Lp(a), and apoCIII-apoA-I, respectively (300 mg dose;P< 0.001 for all), at day 92. Strong correlations in all assay measures were noted with total plasma apoC-III, chylomicron-apoC-III, and VLDL-apoC-III. In conclusion, novel high-throughput ELISAs were developed to detect lipoprotein-associated apoC-III, including for the first time on Lp(a). Volanesorsen uniformly lowers apoC-III on apoB-100, Lp(a), and apoA-I lipoproteins, and may be a potent agent to reduce triglycerides and cardiovascular risk mediated by apoC-III.


Asunto(s)
Apolipoproteína C-III/sangre , Apolipoproteína C-III/genética , Oligonucleótidos Antisentido/genética , Oligonucleótidos Antisentido/uso terapéutico , Apolipoproteína C-III/metabolismo , Enfermedades Cardiovasculares/sangre , Enfermedades Cardiovasculares/genética , Enfermedades Cardiovasculares/terapia , Femenino , Humanos , Masculino , Persona de Mediana Edad , ARN Mensajero/genética , Triglicéridos/sangre
12.
J Biol Chem ; 290(4): 2251-63, 2015 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-25471371

RESUMEN

The ubiquitin E2 enzymes, Ube2g1 and Ube2r1, are able to synthesize Lys-48-linked polyubiquitins without an E3 ligase but how that is accomplished has been unclear. Although both E2s contain essential acidic loops, only Ube2r1 requires an additional C-terminal extension (184-196) for efficient Lys-48-ubiquitylation activity. The presence of Tyr-102 and Tyr-104 in the Ube2g1 acidic loop enhanced both ubiquitin binding and Lys-48-ubiquitylation and distinguished Ube2g1 from the otherwise similar truncated Ube2r1(1-183) (Ube2r1C). Replacement of Gln-105-Ser-106-Gly-107 in the acidic loop of Ube2r1C (Ube2r1C(YGY)) by the corresponding residues from Ube2g1 (Tyr-102-Gly-103-Tyr-104) increased Lys-48-ubiquitylation activity and ubiquitin binding. Two E2∼UB thioester mimics (oxyester and disulfide) were prepared to characterize the ubiquitin binding activity of the acidic loop. The oxyester but not the disulfide derivative was found to be a functional equivalent of the E2∼UB thioester. The ubiquitin moiety of the Ube2r1C(C93S)-[(15)N]UB(K48R) oxyester displayed two-state conformational exchange, whereas the Ube2r1C(C93S/YGY)-[(15)N]UB(K48R) oxyester showed predominantly one state. Together with NMR studies that compared UB(K48R) oxyesters of the wild-type and the acidic loop mutant (Y102G/Y104G) forms of Ube2g1, in vitro ubiquitylation assays with various mutation forms of the E2s revealed how the intramolecular interaction between the acidic loop and the attached donor ubiquitin regulates Lys-48-ubiquitylation activity.


Asunto(s)
Lisina/química , Enzimas Ubiquitina-Conjugadoras/química , Ubiquitina/química , Secuencia de Aminoácidos , Dominio Catalítico , Disulfuros/química , Ésteres/química , Humanos , Espectroscopía de Resonancia Magnética , Datos de Secuencia Molecular , Mutación , Poliubiquitina/química , Unión Proteica , Conformación Proteica , Homología de Secuencia de Aminoácido , Ubiquitina-Proteína Ligasas/química , Ubiquitinación
13.
Genet Med ; 18(8): 833-41, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-26699760

RESUMEN

PURPOSE: We evaluated the incremental prognostic value of combining the CYP2C19 poor metabolizer (PM) and ABCB1 3435 TT for adverse clinical outcomes over conventional risk factors in a percutaneous coronary intervention (PCI) cohort. METHODS: We enrolled 2,188 patients. The primary end point was a composite of death from any cause, nonfatal myocardial infarction (MI), and stroke during 1-year follow-up. The population was stratified into the following four groups: CYP2C19 EM/IM+ABCB1 3435 CC/CT, CYP2C19 EM/IM+ABCB1 3435 TT, CYP2C19 PM+ABCB1 3435 CC/CT, and CYP2C19 PM+ABCB1 3435 TT. RESULTS: A total of 87 (3.97%) primary end-point events occurred (64 deaths, 8 non-fatal MIs and 15 strokes). Multivariate Cox analysis indicated that CYP2C19 PM+ABCB1 3435 TT status was a significant predictor of the primary end point (hazard ratio = 4.51, 95% confidence interval (CI) = 1.92-10.58). However, addition of combined genetic status to the clinical risk model did not improve the model discrimination (C-statistic = 0.786 (95% CI = 0.734-0.837) to 0.785 (95% CI = 0.733-0.838)) or risk reclassification (categorical net reclassification improvement (0.040, P = 0.32), integrated discrimination improvement (0.021, P = 0.026)). CONCLUSIONS: In a real-world East Asian PCI population taking clopidogrel, although the concurrent presence of CYP2C19 PM and ABCB1 TT is a strong independent predictor of adverse outcomes, the combined status of two at-risk variants does not have an incremental prognostic value beyond that of the conventional clinical risk factors.Genet Med 18 8, 833-841.


Asunto(s)
Pueblo Asiatico/genética , Citocromo P-450 CYP2C19/genética , Mutación , Intervención Coronaria Percutánea/efectos adversos , Inhibidores de Agregación Plaquetaria/administración & dosificación , Subfamilia B de Transportador de Casetes de Unión a ATP/genética , Anciano , Anciano de 80 o más Años , Aspirina/administración & dosificación , Aspirina/farmacocinética , Clopidogrel , Stents Liberadores de Fármacos , Asia Oriental , Femenino , Humanos , Masculino , Persona de Mediana Edad , Variantes Farmacogenómicas , Inhibidores de Agregación Plaquetaria/farmacocinética , Pronóstico , Factores de Riesgo , Ticlopidina/administración & dosificación , Ticlopidina/análogos & derivados , Ticlopidina/farmacocinética
14.
World J Microbiol Biotechnol ; 32(5): 84, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-27038954

RESUMEN

An alkaline-thermostable mannanase from Streptomyces sp. CS428 was produced, purified, and biochemically characterized. The extracellular mannanase (Mn428) was purified to homogeneity with 12.4 fold, specific activity of 2406.7 U/mg, and final recovery of 37.6 %. The purified ß-mannanase was found to be a monomeric protein with a molecular mass of approximately 35 kDa as analyzed by SDS-PAGE and zymography. The first N-terminal amino acid sequences of mannanase enzyme were HIRNGNHQLPTG. The optimal temperature and pH for enzyme were 60 °C and 12.5, respectively. The mannanase activities were significantly affected by the presence of metal ions, modulators, and detergents. Km and Vmax values of Mn428 were 1.01 ± 3.4 mg/mL and 5029 ± 85 µmol/min mg, respectively when different concentrations (0.6-10 mg/mL) of locust bean gum galactomannan were used as substrate. The substrate specificity of enzyme showed its highest specificity towards galactomannan which was further hydrolyzed to produce mannose, mannobiose, mannotriose, and a series of mannooligosaccharides. Mannooligosaccharides can be further converted to ethanol production, thus the purified ß-mannanase isolated from Streptomyces sp. CS428 was found to be attractive for biotechnological applications.


Asunto(s)
Proteínas Bacterianas/química , Mananos/química , Oligosacáridos/química , Streptomyces/enzimología , beta-Manosidasa/química , beta-Manosidasa/metabolismo , Proteínas Bacterianas/aislamiento & purificación , Proteínas Bacterianas/metabolismo , Biocatálisis , Estabilidad de Enzimas , Galactosa/análogos & derivados , Concentración de Iones de Hidrógeno , Hidrólisis , Mananos/metabolismo , Peso Molecular , Oligosacáridos/metabolismo , Streptomyces/química , Especificidad por Sustrato , beta-Manosidasa/aislamiento & purificación
15.
Circulation ; 129(3): 304-12, 2014 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-24097439

RESUMEN

BACKGROUND: The risks and benefits of long-term dual antiplatelet therapy remain unclear. METHODS AND RESULTS: This prospective, multicenter, open-label, randomized comparison trial was conducted in 24 clinical centers in Korea. In total, 5045 patients who received drug-eluting stents and were free of major adverse cardiovascular events and major bleeding for at least 12 months after stent placement were enrolled between July 2007 and July 2011. Patients were randomized to receive aspirin alone (n=2514) or clopidogrel plus aspirin (n=2531). The primary end point was a composite of death resulting from cardiac causes, myocardial infarction, or stroke 24 months after randomization. At 24 months, the primary end point occurred in 57 aspirin-alone group patients (2.4%) and 61 dual-therapy group patients (2.6%; hazard ratio, 0.94; 95% confidence interval, 0.66-1.35; P=0.75). The 2 groups did not differ significantly in terms of the individual risks of death resulting from any cause, myocardial infarction, stent thrombosis, or stroke. Major bleeding occurred in 24 (1.1%) and 34 (1.4%) of the aspirin-alone group and dual-therapy group patients, respectively (hazard ratio, 0.71; 95% confidence interval, 0.42-1.20; P=0.20). CONCLUSIONS: Among patients who were on 12-month dual antiplatelet therapy without complications, an additional 24 months of dual antiplatelet therapy versus aspirin alone did not reduce the risk of the composite end point of death from cardiac causes, myocardial infarction, or stroke. CLINICAL TRIAL REGISTRATION URL: http://www.clinicaltrials.gov. Unique identifier: NCT01186146.


Asunto(s)
Angioplastia Coronaria con Balón , Aspirina/administración & dosificación , Enfermedad de la Arteria Coronaria/tratamiento farmacológico , Stents Liberadores de Fármacos , Ticlopidina/análogos & derivados , Anciano , Aspirina/efectos adversos , Clopidogrel , Terapia Combinada , Enfermedad de la Arteria Coronaria/mortalidad , Quimioterapia Combinada , Femenino , Estudios de Seguimiento , Hemorragia/inducido químicamente , Hemorragia/mortalidad , Humanos , Masculino , Persona de Mediana Edad , Inhibidores de Agregación Plaquetaria/administración & dosificación , Inhibidores de Agregación Plaquetaria/efectos adversos , Estudios Prospectivos , Factores de Riesgo , Ticlopidina/administración & dosificación , Ticlopidina/efectos adversos , Resultado del Tratamiento
16.
Small ; 10(20): 4200-6, 2014 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-24975681

RESUMEN

MicroRNAs (miRNAs) are emerging new biomarkers for many human diseases. To fully employ miRNAs as biomarkers for clinical diagnosis, it is most desirable to accurately determine the expression patterns of miRNAs. The optimum miRNA profiling method would feature 1) highest sensitivity with a wide dynamic range for accurate expression patterns, 2) supreme specificity to discriminate single nucleotide polymorphisms (SNPs), and 3) simple sensing processes to minimize measurement variation. Here, an ultra-specific detection method of miRNAs with zeptomole sensitivity is reported by applying bi-temperature hybridizations on single-crystalline plasmonic nanowire interstice (PNI) sensors. This method shows near-perfect accuracy of SNPs and a very low detection limit of 100 am (50 zeptomole) without any amplification or labeling steps. Furthermore, multiplex sensing capability and wide dynamic ranges (100 am-100 pm) of this method allows reliable observation of the expression patterns of miRNAs extracted from human tissues. The PNI sensor offers combination of ultra-specificity and zeptomole sensitivity while requiring two steps of hybridization between short oligonucleotides, which could present the best set of features for optimum miRNA sensing method.


Asunto(s)
MicroARNs/análisis , Nanocables , Temperatura , Secuencia de Bases , Límite de Detección , MicroARNs/genética , Polimorfismo de Nucleótido Simple
17.
Am J Nephrol ; 40(4): 345-52, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25358406

RESUMEN

BACKGROUND/AIMS: Atrial fibrillation (AF) often coexists with acute myocardial infarction (AMI), and chronic kidney disease (CKD) is a major risk for AMI. However, the combined impact of CKD and AF on the mortality and morbidity in AMI population has not been determined. METHODS: Between January 2004 and December 2009, a total of 4,738 AMI patients were enrolled prospectively. Patients were divided into four groups according to the combined status of CKD and AF. The primary endpoint was a combination of 5-year major adverse cardiac and cerebrovascular events (MACCE). RESULTS: The prevalence of AF was significantly higher in CKD patients than in non-CKD patients (6.76 vs. 3.31%, p < 0.001). The highest cumulative event rate of MACCE and death was observed in patients with both CKD and AF (68.5 and 64.0%), respectively. In multivariable analyses, compared with patients with neither AF nor CKD, hazard ratios (HR) for composite of MACCE were 1.66 (95% CI, 1.14-2.41), 1.24 (95% CI, 1.06-1.46), and 2.10 (95% CI, 1.42-3.13) for patients with AF only, those with CKD only, and those with both CKD and AF, respectively (p for interaction = 0.935). Patients with both CKD and AF had a greatest risk for all-cause mortality (HR 2.54; 95% CI, 1.60-4.53), and the significant synergistic interaction was observed between CKD and AF (p for interaction = 0.015). CONCLUSION: The combined effect of AF and CKD on the risk of MACCE after an AMI is stronger than any separate condition, and it confers a synergistic effect on the all-cause mortality risk.


Asunto(s)
Fibrilación Atrial/complicaciones , Trastornos Cerebrovasculares/etiología , Infarto del Miocardio/complicaciones , Sistema de Registros , Insuficiencia Renal Crónica/complicaciones , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/mortalidad , Estudios Prospectivos , República de Corea/epidemiología
18.
Clin Exp Hypertens ; 36(4): 195-9, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24678899

RESUMEN

Morning blood pressure (BP) surge (MS) has been known to be a predictor of cardiovascular events. Currently, few studies have evaluated the underlying mechanism underlying MS, which may include neurohormonal factors and the renin-angiotensin-aldosterone system (RAAS). This study aimed to examine plasma aldosterone concentration (PAC) and plasma renin activity (PRA) and BP parameters with or without MS in never-treated subjects with essential hypertension. This cross-sectional study included a total of 261 patients (mean age: 48.8 years; 60.5% male) with never-treated essential hypertension who were registered in a working group at The Catholic University of Korea. The patients were divided into the MS group, which was defined as having the highest quartile of morning BP increase from sleep (>31 mmHg; n = 66) and the non-MS group (≤31 mmHg; n = 195). We collected 24-h ambulatory BP, pulse wave velocity, ankle brachial index, PAC and PRA from all patients. The measured PAC and PRA were lower in the MS group than in the non-MS group (PAC: 9.0 ± 5.4 ng/dl versus 12.2 ± 8.7 ng/dl, p < 0.001; PRA: 1.7 ± 1.3 ng/ml/h versus 2.6 ± 3.6 ng/ml/h, p = 0.002). The MS group had greater variations in daytime, nighttime and 24-h systolic blood pressure (SBPs) than the non-MS group (24-h SBP: 15.6 ± 4.4 mm Hg for the non-MS group and 18.9 ± 4.9 mmHg for the MS group; p < 0.001 for each). It is generally accepted that the sympathetic nervous system plays a major role in the regulation of BP variability. Therefore, further studies on sympathetic nervous system activation in hypertensives with extreme MS are needed. MS in enrolled patients who were at relatively low risk in this study may be less affected by the RAAS.


Asunto(s)
Aldosterona/sangre , Presión Sanguínea/fisiología , Ritmo Circadiano , Hipertensión/sangre , Sistema Renina-Angiotensina/fisiología , Renina/sangre , Índice Tobillo Braquial , Biomarcadores/sangre , Monitoreo Ambulatorio de la Presión Arterial , Estudios Transversales , Femenino , Estudios de Seguimiento , Humanos , Hipertensión/fisiopatología , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
19.
JAMA Cardiol ; 9(2): 125-133, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38117483

RESUMEN

Importance: In patients with acute myocardial infarction (AMI) who have high ischemic risk, data on the efficacy and safety of the de-escalation strategy of switching from ticagrelor to clopidogrel are lacking. Objective: To evaluate the outcomes of the de-escalation strategy compared with dual antiplatelet therapy (DAPT) with ticagrelor in stabilized patients with AMI and high ischemic risk following percutaneous coronary intervention (PCI). Design, Setting, and Participants: This was a post hoc analysis of the Ticagrelor vs Clopidogrel in Stabilized Patients With Acute Myocardial Infarction (TALOS-AMI) trial, an open-label, assessor-blinded, multicenter, randomized clinical trial. Patients with AMI who had no event during 1 month of ticagrelor-based DAPT after PCI were included. High ischemic risk was defined as having a history of diabetes or chronic kidney disease, multivessel PCI, at least 3 lesions treated, total stent length greater than 60 mm, at least 3 stents implanted, left main PCI, or bifurcation PCI with at least 2 stents. Data were collected from February 14, 2014, to January 21, 2021, and analyzed from December 1, 2021, to June 30, 2022. Intervention: Patients were randomly assigned to either de-escalation from ticagrelor to clopidogrel or ticagrelor-based DAPT. Main Outcomes and Measures: Ischemic outcomes (composite of cardiovascular death, myocardial infarction, ischemic stroke, ischemia-driven revascularization, or stent thrombosis) and bleeding outcomes (Bleeding Academic Research Consortium type 2, 3, or 5 bleeding) were evaluated. Results: Of 2697 patients with AMI (mean [SD] age, 60.0 [11.4] years; 454 [16.8%] female), 1371 (50.8%; 684 assigned to de-escalation and 687 assigned to ticagrelor-based DAPT) had high ischemic risk features and a significantly higher risk of ischemic outcomes than those without high ischemic risk (1326 patients [49.2%], including 665 assigned to de-escalation and 661 assigned to ticagrelor-based DAPT) (hazard ratio [HR], 1.74; 95% CI, 1.15-2.63; P = .01). De-escalation to clopidogrel, compared with ticagrelor-based DAPT, showed no significant difference in ischemic risk across the high ischemic risk group (HR, 0.88; 95% CI, 0.54-1.45; P = .62) and the non-high ischemic risk group (HR, 0.65; 95% CI, 0.33-1.28; P = .21), without heterogeneity (P for interaction = .47). The bleeding risk of the de-escalation group was consistent in both the high ischemic risk group (HR, 0.64; 95% CI, 0.37-1.11; P = .11) and the non-high ischemic risk group (HR, 0.42; 95% CI, 0.24-0.75; P = .003), without heterogeneity (P for interaction = .32). Conclusions and Relevance: In stabilized patients with AMI, the ischemic and bleeding outcomes of an unguided de-escalation strategy with clopidogrel compared with a ticagrelor-based DAPT strategy were consistent without significant interaction, regardless of the presence of high ischemic risk.


Asunto(s)
Infarto del Miocardio , Intervención Coronaria Percutánea , Humanos , Femenino , Persona de Mediana Edad , Masculino , Inhibidores de Agregación Plaquetaria/uso terapéutico , Ticagrelor/uso terapéutico , Clopidogrel/uso terapéutico , Intervención Coronaria Percutánea/efectos adversos , Infarto del Miocardio/tratamiento farmacológico , Hemorragia/inducido químicamente , Hemorragia/epidemiología
20.
Thromb Haemost ; 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38574757

RESUMEN

BACKGROUND: Dyspnea is frequent during ticagrelor-based dual antiplatelet therapy (DAPT) for acute myocardial infarction (AMI). However, its clinical characteristics or management strategy remains uncertain. METHODS: The study assessed 2,617 AMI patients from the Ticagrelor versus Clopidogrel in Stabilized Patients with AMI (TALOS-AMI) trial. Dyspnea during 1-month ticagrelor-based DAPT and following DAPT strategies with continued ticagrelor or de-escalation to clopidogrel from 1 to 12 months were evaluated for drug adherence, subsequent dyspnea, major adverse cardiovascular events (MACE), and bleeding events. RESULTS: Dyspnea was reported by 538 patients (20.6%) during 1 month of ticagrelor-based DAPT. Adherence to allocated DAPT over the study period was lower in the continued ticagrelor arm than the de-escalation to clopidogrel, particularly among the dyspneic population (81.1% vs. 91.5%, p < 0.001). Among ticagrelor-treated patients with dyspnea, those switched to clopidogrel at 1 month had a lower frequency of dyspnea at 3 months (34.3% vs. 51.7%, p < 0.001) and 6 months (25.5% vs. 38.4%, p = 0.002) than those continued with ticagrelor. In patients with dyspnea in their 1-month ticagrelor-based DAPT, de-escalation was not associated with increased MACE (1.3% vs. 3.9%, hazard ratio [HR]: 0.31, 95% confidence interval [CI]: 0.08-1.11, p = 0.07) or clinically relevant bleeding (3.2% vs. 6.2%, HR: 0.51, 95% CI: 0.22-1.19, p = 0.12) at 1 year. CONCLUSION: Dyspnea is a common side effect among ticagrelor-based DAPTs in AMI patients. Switching from ticagrelor to clopidogrel after 1 month in AMI patients may provide a reasonable option to alleviate subsequent dyspnea in ticagrelor-relevant dyspneic patients, without increasing the risk of ischemic events (NCT02018055).

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