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1.
Cell ; 161(3): 595-609, 2015 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-25892225

RESUMEN

Organisms must be able to respond to low oxygen in a number of homeostatic and pathological contexts. Regulation of hypoxic responses via the hypoxia-inducible factor (HIF) is well established, but evidence indicates that other, HIF-independent mechanisms are also involved. Here, we report a hypoxic response that depends on the accumulation of lactate, a metabolite whose production increases in hypoxic conditions. We find that the NDRG3 protein is degraded in a PHD2/VHL-dependent manner in normoxia but is protected from destruction by binding to lactate that accumulates under hypoxia. The stabilized NDRG3 protein binds c-Raf to mediate hypoxia-induced activation of Raf-ERK pathway, promoting angiogenesis and cell growth. Inhibiting cellular lactate production abolishes the NDRG3-mediated hypoxia responses. Our study, therefore, elucidates the molecular basis for lactate-induced hypoxia signaling, which can be exploited for the development of therapies targeting hypoxia-induced diseases.


Asunto(s)
Hipoxia/metabolismo , Ácido Láctico/metabolismo , Hipoxia de la Célula , Línea Celular , Regulación de la Expresión Génica , Humanos , Prolina Dioxigenasas del Factor Inducible por Hipoxia/metabolismo , Péptidos y Proteínas de Señalización Intracelular , Sistema de Señalización de MAP Quinasas , Neovascularización Patológica/metabolismo , Proteínas del Tejido Nervioso/química , Proteínas del Tejido Nervioso/metabolismo , Oxígeno/metabolismo , Unión Proteica , Quinasas raf/metabolismo
2.
Nature ; 619(7971): 755-760, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37438523

RESUMEN

Displays in which arrays of microscopic 'particles', or chiplets, of inorganic light-emitting diodes (LEDs) constitute the pixels, termed MicroLED displays, have received considerable attention1,2 because they can potentially outperform commercially available displays based on organic LEDs3,4 in terms of power consumption, colour saturation, brightness and stability and without image burn-in issues1,2,5-7. To manufacture these displays, LED chiplets must be epitaxially grown on separate wafers for maximum device performance and then transferred onto the display substrate. Given that the number of LEDs needed for transfer is tremendous-for example, more than 24 million chiplets smaller than 100 µm are required for a 50-inch, ultra-high-definition display-a technique capable of assembling tens of millions of individual LEDs at low cost and high throughput is needed to commercialize MicroLED displays. Here we demonstrate a MicroLED lighting panel consisting of more than 19,000 disk-shaped GaN chiplets, 45 µm in diameter and 5 µm in thickness, assembled in 60 s by a simple agitation-based, surface-tension-driven fluidic self-assembly (FSA) technique with a yield of 99.88%. The creation of this level of large-scale, high-yield FSA of sub-100-µm chiplets was considered a significant challenge because of the low inertia of the chiplets. Our key finding in overcoming this difficulty is that the addition of a small amount of poloxamer to the assembly solution increases its viscosity which, in turn, increases liquid-to-chiplet momentum transfer. Our results represent significant progress towards the ultimate goal of low-cost, high-throughput manufacture of full-colour MicroLED displays by FSA.

3.
Cell ; 153(3): 666-77, 2013 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-23622249

RESUMEN

The analysis of exonic DNA from prostate cancers has identified recurrently mutated genes, but the spectrum of genome-wide alterations has not been profiled extensively in this disease. We sequenced the genomes of 57 prostate tumors and matched normal tissues to characterize somatic alterations and to study how they accumulate during oncogenesis and progression. By modeling the genesis of genomic rearrangements, we identified abundant DNA translocations and deletions that arise in a highly interdependent manner. This phenomenon, which we term "chromoplexy," frequently accounts for the dysregulation of prostate cancer genes and appears to disrupt multiple cancer genes coordinately. Our modeling suggests that chromoplexy may induce considerable genomic derangement over relatively few events in prostate cancer and other neoplasms, supporting a model of punctuated cancer evolution. By characterizing the clonal hierarchy of genomic lesions in prostate tumors, we charted a path of oncogenic events along which chromoplexy may drive prostate carcinogenesis.


Asunto(s)
Aberraciones Cromosómicas , Regulación Neoplásica de la Expresión Génica , Genoma Humano , Neoplasias de la Próstata/genética , Adenocarcinoma/genética , Adenocarcinoma/patología , Estudios de Cohortes , Estudio de Asociación del Genoma Completo , Humanos , Masculino , Tumores Neuroendocrinos/genética , Tumores Neuroendocrinos/patología , Neoplasias de la Próstata/patología
4.
Cell ; 146(3): 396-407, 2011 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-21816275

RESUMEN

In E. coli, MinD recruits MinE to the membrane, leading to a coupled oscillation required for spatial regulation of the cytokinetic Z ring. How these proteins interact, however, is not clear because the MinD-binding regions of MinE are sequestered within a six-stranded ß sheet and masked by N-terminal helices. minE mutations that restore interaction between some MinD and MinE mutants were isolated. These mutations alter the MinE structure leading to release of the MinD-binding regions and the N-terminal helices that bind the membrane. Crystallization of MinD-MinE complexes revealed a four-stranded ß sheet MinE dimer with the released ß strands (MinD-binding regions) converted to α helices bound to MinD dimers. These results identify the MinD-dependent conformational changes in MinE that convert it from a latent to an active form and lead to a model of how MinE persists at the MinD-membrane surface.


Asunto(s)
Adenosina Trifosfatasas/química , Proteínas de Ciclo Celular/química , Proteínas de Escherichia coli/química , Escherichia coli/citología , Escherichia coli/metabolismo , Adenosina Trifosfatasas/genética , Adenosina Trifosfatasas/metabolismo , Proteínas Bacterianas/metabolismo , Secuencia de Bases , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Cristalografía por Rayos X , Citocinesis , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Bacterias Gramnegativas/metabolismo , Modelos Biológicos , Modelos Moleculares , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Estructura Secundaria de Proteína , Alineación de Secuencia
5.
Proc Natl Acad Sci U S A ; 120(17): e2221535120, 2023 04 25.
Artículo en Inglés | MEDLINE | ID: mdl-37075071

RESUMEN

Multiple sclerosis (MS) is an incurable autoimmune disease and is currently treated by systemic immunosuppressants with off-target side effects. Although aberrant myeloid function is often observed in MS plaques in the central nervous system (CNS), the role of myeloid cells in therapeutic intervention is currently overlooked. Here, we developed a myeloid cell-based strategy to reduce the disease burden in experimental autoimmune encephalomyelitis (EAE), a mouse model of progressive MS. We developed monocyte-adhered microparticles ("backpacks") for activating myeloid cell phenotype to an anti-inflammatory state through localized interleukin-4 and dexamethasone signals. We demonstrate that backpack-laden monocytes infiltrated into the inflamed CNS and modulated both the local and systemic immune responses. Within the CNS, backpack-carrying monocytes regulated both the infiltrating and tissue-resident myeloid cell compartments in the spinal cord for functions related to antigen presentation and reactive species production. Treatment with backpack-monocytes also decreased the level of systemic pro-inflammatory cytokines. Additionally, backpack-laden monocytes induced modulatory effects on TH1 and TH17 populations in the spinal cord and blood, demonstrating cross talk between the myeloid and lymphoid arms of disease. Backpack-carrying monocytes conferred therapeutic benefit in EAE mice, as quantified by improved motor function. The use of backpack-laden monocytes offers an antigen-free, biomaterial-based approach to precisely tune cell phenotype in vivo, demonstrating the utility of myeloid cells as a therapeutic modality and target.


Asunto(s)
Encefalomielitis Autoinmune Experimental , Esclerosis Múltiple , Ratones , Animales , Esclerosis Múltiple/terapia , Células Mieloides , Sistema Nervioso Central , Monocitos , Ratones Endogámicos C57BL
6.
Nat Mater ; 23(6): 782-789, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38491147

RESUMEN

Coupling of spin and charge currents to structural chirality in non-magnetic materials, known as chirality-induced spin selectivity, is promising for application in spintronic devices at room temperature. Although the chirality-induced spin selectivity effect has been identified in various chiral materials, its Onsager reciprocal process, the inverse chirality-induced spin selectivity effect, remains unexplored. Here we report the observation of the inverse chirality-induced spin selectivity effect in chiral assemblies of π-conjugated polymers. Using spin-pumping techniques, the inverse chirality-induced spin selectivity effect enables quantification of the magnitude of the longitudinal spin-to-charge conversion driven by chirality-induced spin selectivity in different chiral polymers. By widely tuning conductivities and supramolecular chiral structures via a printing method, we found a very long spin relaxation time of up to several nanoseconds parallel to the chiral axis. Our demonstration of the inverse chirality-induced spin selectivity effect suggests possibilities for elucidating the puzzling interplay between spin and chirality, and opens a route for spintronic applications using printable chiral assemblies.

7.
Circ Res ; 132(7): 828-848, 2023 03 31.
Artículo en Inglés | MEDLINE | ID: mdl-36883446

RESUMEN

BACKGROUND: Signaling by cAMP is organized in multiple distinct subcellular nanodomains regulated by cAMP-hydrolyzing PDEs (phosphodiesterases). Cardiac ß-adrenergic signaling has served as the prototypical system to elucidate cAMP compartmentalization. Although studies in cardiac myocytes have provided an understanding of the location and properties of a handful of cAMP subcellular compartments, an overall view of the cellular landscape of cAMP nanodomains is missing. METHODS: Here, we combined an integrated phosphoproteomics approach that takes advantage of the unique role that individual PDEs play in the control of local cAMP, with network analysis to identify previously unrecognized cAMP nanodomains associated with ß-adrenergic stimulation. We then validated the composition and function of one of these nanodomains using biochemical, pharmacological, and genetic approaches and cardiac myocytes from both rodents and humans. RESULTS: We demonstrate the validity of the integrated phosphoproteomic strategy to pinpoint the location and provide critical cues to determine the function of previously unknown cAMP nanodomains. We characterize in detail one such compartment and demonstrate that the PDE3A2 isoform operates in a nuclear nanodomain that involves SMAD4 (SMAD family member 4) and HDAC-1 (histone deacetylase 1). Inhibition of PDE3 results in increased HDAC-1 phosphorylation, leading to inhibition of its deacetylase activity, derepression of gene transcription, and cardiac myocyte hypertrophic growth. CONCLUSIONS: We developed a strategy for detailed mapping of subcellular PDE-specific cAMP nanodomains. Our findings reveal a mechanism that explains the negative long-term clinical outcome observed in patients with heart failure treated with PDE3 inhibitors.


Asunto(s)
AMP Cíclico , Miocitos Cardíacos , Humanos , Proteómica , Hidrolasas Diéster Fosfóricas , Hipertrofia , Adrenérgicos
8.
Genesis ; 62(1): e23584, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-38102875

RESUMEN

A wide variety of CreERT2 driver lines are available for genetic manipulation of adult-born neurons in the mouse brain. These tools have been instrumental in studying fate potential, migration, circuit integration, and morphology of the stem cells supporting lifelong neurogenesis. Despite a wealth of tools, genetic manipulation of adult-born neurons for circuit and behavioral studies has been limited by poor specificity of many driver lines targeting early progenitor cells and by the inaccessibility of lines selective for later stages of neuronal maturation. We sought to address these limitations by creating a new CreERT2 driver line targeted to the endogenous mouse doublecortin locus as a marker of fate-specified neuroblasts and immature neurons. Our new model places a T2A-CreERT2 cassette immediately downstream of the Dcx coding sequence on the X chromosome, allowing expression of both Dcx and CreERT2 proteins in the endogenous spatiotemporal pattern for this gene. We demonstrate that the new mouse line drives expression of a Cre-dependent reporter throughout the brain in neonatal mice and in known neurogenic niches of adult animals. The line has been deposited with the Jackson Laboratory and should provide an accessible tool for studies targeting fate-restricted neuronal precursors.


Asunto(s)
Células-Madre Neurales , Neuronas , Ratones , Animales , Ratones Transgénicos , Neuronas/metabolismo , Células-Madre Neurales/metabolismo , Neurogénesis/genética , Encéfalo
9.
Circulation ; 147(2): 108-117, 2023 01 10.
Artículo en Inglés | MEDLINE | ID: mdl-36342475

RESUMEN

BACKGROUND: Long-term outcomes of antiplatelet monotherapy in patients who receive percutaneous coronary intervention are unknown. The HOST-EXAM (Harmonizing Optimal Strategy for Treatment of Coronary Artery Stenosis-Extended Antiplatelet Monotherapy) Extended study reports the posttrial follow-up results of the original HOST-EXAM trial. METHODS: From March 2014 through May 2018, 5438 patients who maintained dual antiplatelet therapy without clinical events for 12±6 months after percutaneous coronary intervention with drug-eluting stents were randomly assigned in a 1:1 ratio to receive clopidogrel (75 mg once daily) or aspirin (100 mg once daily). The primary end point (a composite of all-cause death, nonfatal myocardial infarction, stroke, readmission attributable to acute coronary syndrome, and Bleeding Academic Research Consortium type 3 or greater bleeding), secondary thrombotic end point (cardiac death, nonfatal myocardial infarction, ischemic stroke, readmission attributable to acute coronary syndrome, and definite or probable stent thrombosis), and bleeding end point (Bleeding Academic Research Consortium type 2 or greater bleeding) were analyzed during the extended follow-up period. Analysis was performed on the per-protocol population (2431 patients in the clopidogrel group and 2286 patients in the aspirin group). RESULTS: During a median follow-up of 5.8 years (interquartile range, 4.8-6.2 years), the primary end point occurred in 12.8% and 16.9% in the clopidogrel and aspirin groups, respectively (hazard ratio, 0.74 [95% CI, 0.63-0.86]; P<0.001). The clopidogrel group had a lower risk for the secondary thrombotic end point (7.9% versus 11.9%; hazard ratio, 0.66 [95% CI, 0.55-0.79]; P<0.001) and secondary bleeding end point (4.5% versus 6.1%; hazard ratio, 0.74 [95% CI, 0.57-0.94]; P=0.016). There was no significant difference in the incidence of all-cause death between the 2 groups (6.2% versus 6.0%; hazard ratio, 1.04 [95% CI, 0.82-1.31]; P=0.742). Landmark analysis at 2 years showed that the beneficial effect of clopidogrel was consistent throughout the follow-up period. CONCLUSIONS: During an extended follow-up of >5 years after randomization, clopidogrel monotherapy compared with aspirin monotherapy was associated with lower rates of the composite net clinical outcome in patients without clinical events for 12±6 months after percutaneous coronary intervention with drug-eluting stents. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT02044250.


Asunto(s)
Síndrome Coronario Agudo , Infarto del Miocardio , Intervención Coronaria Percutánea , Trombosis , Humanos , Clopidogrel/uso terapéutico , Aspirina/efectos adversos , Inhibidores de Agregación Plaquetaria/efectos adversos , Síndrome Coronario Agudo/tratamiento farmacológico , Síndrome Coronario Agudo/cirugía , Quimioterapia Combinada , Infarto del Miocardio/epidemiología , Infarto del Miocardio/tratamiento farmacológico , Hemorragia/inducido químicamente , Hemorragia/tratamiento farmacológico , Intervención Coronaria Percutánea/efectos adversos , Trombosis/tratamiento farmacológico , Resultado del Tratamiento
10.
Circulation ; 147(18): 1358-1368, 2023 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-36871230

RESUMEN

BACKGROUND: Limited data are available on short-term dual antiplatelet therapy (DAPT) after percutaneous coronary intervention using third-generation drug-eluting stents with ultrathin struts and advanced polymer technology. We investigated whether 3- to 6-month DAPT was noninferior to 12-month DAPT after implantation of drug-eluting stents with ultrathin struts and advanced polymer technology. METHODS: We performed an open-label, randomized trial at 37 centers in South Korea. We enrolled patients undergoing percutaneous coronary intervention using the Orsiro biodegradable-polymer sirolimus-eluting stents or the Coroflex ISAR polymer-free sirolimus-eluting stents. Patients with ST-segment-elevation myocardial infarction were excluded. Patients were randomly assigned to receive either 3- to 6-month or 12-month DAPT after percutaneous coronary intervention. The choice of antiplatelet medications was at the physician's discretion. The primary outcome was a net adverse clinical event, a composite of cardiac death, target vessel myocardial infarction, clinically driven target lesion revascularization, stent thrombosis, or major bleeding, defined as Bleeding Academic Research Consortium type 3 or 5 at 12 months. The major secondary outcomes were target lesion failure, a composite of cardiac death, target vessel myocardial infarction, clinically driven target lesion revascularization, and major bleeding. RESULTS: A total of 2013 patients (mean age, 65.7±10.5 years; 1487 males [73.9%]; 1110 [55.1%] presented with acute coronary syndrome) were randomly assigned to 3- to 6-month DAPT (n=1002) or 12-month DAPT (n=1011). The primary outcome occurred in 37 (3.7%) patients in the 3- to 6-month DAPT group and 41 (4.1%) in the 12-month DAPT group. The noninferiority of the 3- to 6-month DAPT group to the 12-month DAPT group was met (absolute risk difference, -0.4% [1-sided 95% CI, -∞% to 1.1%]; P<0.001 for noninferiority). There were no significant differences in target lesion failure (hazard ratio, 0.98 [95% CI, 0.56-1.71], P=0.94) or major bleeding (hazard ratio, 0.82 [95% CI, 0.41-1.61], P=0.56) between the 2 groups. Across various subgroups, the treatment effect of 3- to 6-month DAPT was consistent for net adverse clinical event. CONCLUSIONS: Among patients undergoing percutaneous coronary intervention using third-generation drug-eluting stents, 3- to 6-month DAPT was noninferior to 12-month DAPT for net adverse clinical event. Further research is needed to generalize this finding to other populations and to determine the ideal regimen for 3- to 6-month DAPT. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT02601157.


Asunto(s)
Stents Liberadores de Fármacos , Infarto del Miocardio , Intervención Coronaria Percutánea , Masculino , Humanos , Persona de Mediana Edad , Anciano , Inhibidores de Agregación Plaquetaria/uso terapéutico , Infarto del Miocardio/tratamiento farmacológico , Hemorragia/inducido químicamente , Sirolimus , Muerte , Intervención Coronaria Percutánea/efectos adversos , Resultado del Tratamiento
11.
Eur J Immunol ; 53(5): e2250048, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36815313

RESUMEN

Keratinocytes are pivotal cells in the pathogenesis of atopic dermatitis (AD) as much as Th2 cells. In this sense, regulation of pro-inflammatory features of keratinocytes might be useful for AD patients. P2X7R-mediated activation of NLRP3 inflammasome (N3I) in keratinocytes and myeloid cells plays crucial roles in AD. Nonetheless, inhibition of P2X7R has not been feasible because of polymorphisms and ubiquitous expression of P2X7R. Here, we report that GPCR19 colocalizes with P2X7R, and a GPCR19 agonist (taurodeoxycholate [TDCA]) inhibits the activation of P2X7R. Noncistronically, TDCA inhibits NF-kB activation via the adenylate cyclase-PKA pathway and BzATP-mediated Ca++ mobilization. Cistronically, TDCA suppresses the expression of P2X7R and N3I components in keratinocytes. NLRP3 oligomerization and the production of mature IL-1ß and IL-18 was suppressed by TDCA treatment in keratinocytes. Topical TDCA treatment ameliorates proinflammatory features of AD in mice induced by DNCB, MC903, or oxazolone. Taken together, a GPCR19 agonist such as TDCA might inhibit P2X7R-mediated N3I activation of keratinocytes, which is crucial for the pathogenesis of AD.


Asunto(s)
Dermatitis Atópica , Ratones , Animales , Dermatitis Atópica/tratamiento farmacológico , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Ratones Endogámicos BALB C , Queratinocitos/metabolismo , Inflamasomas/metabolismo , Citocinas/metabolismo
12.
Small ; : e2309634, 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38845070

RESUMEN

A novel green-absorbing organic molecule featuring dual intramolecular chalcogen bonds is synthesized and characterized. This molecule incorporates two such bonds: one between a tellurium atom and the oxygen atom of a carbonyl moiety, and the other between the tellurium atom and the adjacent nitrogen atom within a pyridine moiety. The molecule, featuring dual intramolecular chalcogen bonds exhibits a narrow absorption spectrum and elevated absorption coefficients, closely aligned with a resonance parameter of approximately 0.5. This behavior is due to its cyanine-like characteristics and favorable electrical properties, which are a direct result of its rigid, planar molecular structure. Therefore, this organic molecule forming dual intramolecular chalcogen bonds achieves superior optoelectronic performance in green-selective photodetectors, boasting an external quantum efficiency of over 65% and a full-width at half maximum of less than 95 nm while maintaining the performance after 1000 h of heating aging at 85 °C. Such organic photodetectors are poised to enhance stacked organic photodetector-on-silicon hybrid image sensors, paving the way for the next-generation of high-resolution and high-sensitivity image sensors.

13.
Ophthalmology ; 131(3): 288-301, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37832727

RESUMEN

PURPOSE: To assess the risk of dementia in individuals with newly diagnosed ocular motor cranial neuropathy (OMCN). DESIGN: A nationwide, population-based cohort study using authenticated data from the Korean National Health Insurance Service (KNHIS). PARTICIPANTS: This study included 60 781 patients with OMCN who received a diagnosis between 2010 and 2017 and were followed up through 2018, with an average follow-up of 3.37 ± 2.21 years with a 1-year lag. After excluding patients with disease related to oculomotor dysfunction preceding the OMCN diagnosis, a total of 52 076 patients with OMCN were established. Of these, 23 642 patients who had participated in the National Health Screening Program (NHSP) within 2 years before the OMCN diagnosis were included. After applying the exclusion criteria, the final cohort comprised 19 243 patients and 96 215 age and sex-matched control participants without OMCN. METHODS: We identified patients with newly diagnosed OMCN in the KNHIS database and collected participant characteristics from the health checkup records of the NHSP. The study end point was determined by the first claim with a dementia diagnostic code and antidementia medications. The association of OMCN with dementia risk was examined using Cox proportional hazards regression analysis, adjusting for potential confounding factors. MAIN OUTCOME MEASURES: The main outcome measures were hazard ratios (HRs) and 95% confidence intervals (CIs) for all-cause dementia (ACD), Alzheimer's disease (AD), and vascular dementia (VaD) development in patients with OMCN relative to those without OMCN. RESULTS: Patients with newly diagnosed OMCN demonstrated higher metabolic comorbidities than those without OMCN. New OMCN was associated with an elevated risk of ACD (HR, 1.203; 95% CI, 1.113-1.300), AD (HR, 1.137; 95% CI, 1.041-1.243), and VaD (HR, 1.583; 95% CI, 1.286-1.948), independent of potential confounding factors. The younger age groups exhibited a stronger association between OMCN and ACD (HR, 8.690 [< 50 years] vs. 1.192 [≥ 50 years]; P = 0.0004; HR, 2.517 [< 65 years] vs. 1.099 [≥ 65 years]; P < 0.0001). CONCLUSIONS: This nationwide population-based study assessed the association between OMCN and dementia risk. Our results demonstrated a robust relationship between OMCN and the risk of dementia, particularly in the younger population. FINANCIAL DISCLOSURE(S): The author(s) have no proprietary or commercial interest in any materials discussed in this article.


Asunto(s)
Enfermedad de Alzheimer , Enfermedades de los Nervios Craneales , Humanos , Niño , Estudios de Cohortes , Estudios Retrospectivos , Factores de Riesgo , Enfermedad de Alzheimer/diagnóstico
14.
Ann Neurol ; 94(5): 836-847, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37532684

RESUMEN

OBJECTIVE: The effect of clonal hematopoiesis of indeterminate potential (CHIP) on the manifestation and clinical outcomes of acute ischemic stroke (AIS) has not been fully elucidated. METHODS: Patients with AIS were included from a prospective registry coupled with a DNA repository. Targeted next-generation sequencing on 25 genes that are frequently mutated in hematologic neoplasms was performed. The prevalence of CHIP was compared between patients with AIS and age-matched healthy individuals. A multivariate linear or logistic regression model was used to assess the association among CHIP and stroke severity, hemorrhagic transformation, and functional outcome at 90 days. RESULTS: In total, 380 patients with AIS (mean age = 67.2 ± 12.7 years; 41.3% women) and 446 age-matched controls (mean age = 67.2 ± 8.7 years; 31.4% women) were analyzed. The prevalence of CHIP was significantly higher in patients with AIS than in the healthy controls (29.0 vs 22.0%, with variant allele frequencies of 1.5%, p = 0.024). PPM1D was found to be most significantly associated with incident AIS (adjusted odds ratio [aOR] = 7.85, 95% confidence interval [CI] = 1.83-33.63, p = 0.006). The presence of CHIP was significantly associated with the initial National Institutes of Health Stroke Scale (NIHSS) score (ß = 1.67, p = 0.022). Furthermore, CHIP was independently associated with the occurrence of hemorrhagic transformation (65/110 clonal hematopoiesis positive [CH+] vs 56/270 CH negative [CH-], aOR = 5.63, 95% CI = 3.24-9.77, p < 0.001) and 90-day functional disability (72/110 [CH+] vs 99/270 [CH-], aOR = 2.15, 95% CI = 1.20-3.88, p = 0.011). INTERPRETATION: CH was significantly associated with incident AIS. Moreover, particularly, sequence variations in PPM1D, TET2, and DNMT3A represent a new prognostic factor for AIS. ANN NEUROL 2023;94:836-847.


Asunto(s)
Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Humanos , Femenino , Persona de Mediana Edad , Anciano , Masculino , Hematopoyesis Clonal , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/genética
15.
Acta Neuropathol ; 147(1): 61, 2024 03 25.
Artículo en Inglés | MEDLINE | ID: mdl-38526616

RESUMEN

TMEM106B is a risk modifier of multiple neurological conditions, where a single coding variant and multiple non-coding SNPs influence the balance between susceptibility and resilience. Two key questions that emerge from past work are whether the lone T185S coding variant contributes to protection, and if the presence of TMEM106B is helpful or harmful in the context of disease. Here, we address both questions while expanding the scope of TMEM106B study from TDP-43 to models of tauopathy. We generated knockout mice with constitutive deletion of TMEM106B, alongside knock-in mice encoding the T186S knock-in mutation (equivalent to the human T185S variant), and crossed both with a P301S transgenic tau model to study how these manipulations impacted disease phenotypes. We found that TMEM106B deletion accelerated cognitive decline, hind limb paralysis, tau pathology, and neurodegeneration. TMEM106B deletion also increased transcriptional correlation with human AD and the functional pathways enriched in KO:tau mice aligned with those of AD. In contrast, the coding variant protected against tau-associated cognitive decline, synaptic impairment, neurodegeneration, and paralysis without affecting tau pathology. Our findings reveal that TMEM106B is a critical safeguard against tau aggregation, and that loss of this protein has a profound effect on sequelae of tauopathy. Our study further demonstrates that the coding variant is functionally relevant and contributes to neuroprotection downstream of tau pathology to preserve cognitive function.


Asunto(s)
Proteínas de la Membrana , Proteínas del Tejido Nervioso , Tauopatías , Animales , Humanos , Ratones , Modelos Animales de Enfermedad , Proteínas de la Membrana/genética , Ratones Noqueados , Ratones Transgénicos , Mutación , Proteínas del Tejido Nervioso/genética , Parálisis/genética , Polimorfismo de Nucleótido Simple , Proteínas tau/genética , Proteínas tau/metabolismo , Tauopatías/patología
16.
Respir Res ; 25(1): 213, 2024 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-38762465

RESUMEN

BACKGROUND: Obesity is associated with airway hyperresponsiveness and lung fibrosis, which may reduce the effectiveness of standard asthma treatment in individuals suffering from both conditions. Statins and proprotein convertase subtilisin/kexin-9 inhibitors not only reduce serum cholesterol, free fatty acids but also diminish renin-angiotensin system activity and exhibit anti-inflammatory effects. These mechanisms may play a role in mitigating lung pathologies associated with obesity. METHODS: Male C57BL/6 mice were induced to develop obesity through high-fat diet for 16 weeks. Conditional TGF-ß1 transgenic mice were fed a normal diet. These mice were given either atorvastatin or proprotein convertase subtilisin/kexin-9 inhibitor (alirocumab), and the impact on airway hyperresponsiveness and lung pathologies was assessed. RESULTS: High-fat diet-induced obesity enhanced airway hyperresponsiveness, lung fibrosis, macrophages in bronchoalveolar lavage fluid, and pro-inflammatory mediators in the lung. These lipid-lowering agents attenuated airway hyperresponsiveness, macrophages in BALF, lung fibrosis, serum leptin, free fatty acids, TGF-ß1, IL-1ß, IL-6, and IL-17a in the lung. Furthermore, the increased RAS, NLRP3 inflammasome, and cholecystokinin in lung tissue of obese mice were reduced with statin or alirocumab. These agents also suppressed the pro-inflammatory immune responses and lung fibrosis in TGF-ß1 over-expressed transgenic mice with normal diet. CONCLUSIONS: Lipid-lowering treatment has the potential to alleviate obesity-induced airway hyperresponsiveness and lung fibrosis by inhibiting the NLRP3 inflammasome, RAS and cholecystokinin activity.


Asunto(s)
Dieta Alta en Grasa , Inhibidores de Hidroximetilglutaril-CoA Reductasas , Ratones Endogámicos C57BL , Ratones Transgénicos , Obesidad , Fibrosis Pulmonar , Animales , Masculino , Dieta Alta en Grasa/efectos adversos , Obesidad/tratamiento farmacológico , Obesidad/metabolismo , Ratones , Inhibidores de Hidroximetilglutaril-CoA Reductasas/farmacología , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Fibrosis Pulmonar/prevención & control , Fibrosis Pulmonar/patología , Fibrosis Pulmonar/metabolismo , Fibrosis Pulmonar/tratamiento farmacológico , Inhibidores de PCSK9 , Atorvastatina/farmacología , Atorvastatina/uso terapéutico , Ratones Obesos , Proproteína Convertasa 9/metabolismo , Proproteína Convertasa 9/genética , Anticuerpos Monoclonales/farmacología , Anticuerpos Monoclonales/uso terapéutico , Hiperreactividad Bronquial/prevención & control , Hiperreactividad Bronquial/tratamiento farmacológico , Hiperreactividad Bronquial/metabolismo , Hiperreactividad Bronquial/fisiopatología , Anticuerpos Monoclonales Humanizados
17.
Artículo en Inglés | MEDLINE | ID: mdl-38418215

RESUMEN

BACKGROUND: Optic neuritis (ON) prognosis is influenced by various factors including attack severity, underlying aetiologies, treatments and consequences of previous episodes. This study, conducted on a large cohort of first ON episodes, aimed to identify unique prognostic factors for each ON subtype, while excluding any potential influence from pre-existing sequelae. METHODS: Patients experiencing their first ON episodes, with complete aquaporin-4 (AQP4) and myelin oligodendrocyte glycoprotein (MOG) antibody testing, and clinical data for applying multiple sclerosis (MS) diagnostic criteria, were enrolled. 427 eyes from 355 patients from 10 hospitals were categorised into four subgroups: neuromyelitis optica with AQP4 IgG (NMOSD-ON), MOG antibody-associated disease (MOGAD-ON), ON in MS (MS-ON) or idiopathic ON (ION). Prognostic factors linked to complete recovery (regaining 20/20 visual acuity (VA)) or moderate recovery (regaining 20/40 VA) were assessed through multivariable Cox regression analysis. RESULTS: VA at nadir emerged as a robust prognostic factor for both complete and moderate recovery, spanning all ON subtypes. Early intravenous methylprednisolone (IVMP) was associated with enhanced complete recovery in NMOSD-ON and MOGAD-ON, but not in MS-ON or ION. Interestingly, in NMOSD-ON, even a slight IVMP delay in IVMP by >3 days had a significant negative impact, whereas a moderate delay up to 7-9 days was permissible in MOGAD-ON. Female sex predicted poor recovery in MOGAD-ON, while older age hindered moderate recovery in NMOSD-ON and ION. CONCLUSION: This comprehensive multicentre analysis on first-onset ON unveils subtype-specific prognostic factors. These insights will assist tailored treatment strategies and patient counselling for ON.

18.
Br J Nutr ; : 1-8, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38618917

RESUMEN

The purpose of this study was to compare single- and multi-frequency bioimpedance (BIA) devices against dual-energy X-ray absorptiometry (DXA) for appendicular lean mass (ALM) and muscle quality index (MQI) metrics in Hispanic adults. One hundred thirty-one Hispanic adults (18-55 years) participated in this study. ALM was measured with single-frequency bioimpedance analysis (SFBIA), multi-frequency bioimpedance analysis (MFBIA) and DXA. ALMTOTAL (left arm + right arm + left leg + right leg) and ALMARMS (left arm + right arm) were computed for all three devices. Handgrip strength (HGS) was measured using a dynamometer. The average HGS was used for all MQI models (highest left hand + highest right hand)/2. MQIARMS was defined as the ratio between HGS and ALMARMS. MQITOTAL was established as the ratio between HGS and ALMTOTAL. SFBIA and MFBIA had strong correlations with DXA for all ALM and MQI metrics (Lin's concordance correlation coefficient values ranged from 0·86 (MQIMFBIA-ARMS) to 0·97 (Arms LMSFBIA); all P < 0·001). Equivalence testing varied between methods (e.g. SFBIA v. DXA) when examining the different metrics (i.e. ALMTOTAL, ALMARMS, MQITOTAL and MQIARMS). MQIARMS was the only metric that did not differ from the line of identity and had no proportional bias when comparing all the devices against each other. The current study findings demonstrate good overall agreement between SFBIA, MFBIA and DXA for ALMTOTAL and ALMARMS in a Hispanic population. However, SFBIA and MFBIA have better agreement with DXA when used to compute MQIARMS than MQITOTAL.

19.
BMC Neurol ; 24(1): 14, 2024 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-38166838

RESUMEN

BACKGROUND: Dilated perivascular spaces (DPVS), known as one of imaging markers in cerebral small vessel disease, may be found in patients with moyamoya disease (MMD). However, little is known about DPVS in MMD. The purpose of this study was to investigate the distribution pattern of dPVS in children and adults with MMD and determine whether it is related to steno-occlusive changes of MMD. METHODS: DPVS was scored in basal ganglia (BG) and white matter (WM) on T2-weighted imaging, using a validated 4-point semi-quantitative score. The degree of dPVS was classified as high (score > 2) or low (score ≤ 2) grade. The steno-occlusive changes on MR angiography (MRA) was scored using a validated MRA grading. Asymmetry of DPVS and MRA grading was defined as a difference of 1 grade or higher between hemispheres. RESULTS: Fifty-one patients with MMD (mean age 24.9 ± 21.1 years) were included. Forty-five (88.2%) patients had high WM-DPVS grade (degree 3 or 4). BG-DPVS was found in 72.5% of all patients and all were low grade (degree 1 or 2). The distribution patterns of DPVS degree in BG (P = 1.000) and WM (P = 0.767) were not different between child and adult groups. The asymmetry of WM-DPVS (26%) and MRA grade (42%) were significantly correlated to each other (Kendall's tau-b = 0.604, P < 0.001). CONCLUSIONS: DPVS of high grade in MMD is predominantly found in WM, which was not different between children and adults. The correlation between asymmetry of WM-DPVS degree and MRA grade suggests that weak cerebral artery pulsation due to steno-occlusive changes may affect WM-DPVS in MMD.


Asunto(s)
Enfermedad de Moyamoya , Sustancia Blanca , Adulto , Niño , Humanos , Preescolar , Adolescente , Adulto Joven , Persona de Mediana Edad , Enfermedad de Moyamoya/diagnóstico por imagen , Angiografía por Resonancia Magnética , Imagen por Resonancia Magnética/métodos , Sustancia Blanca/diagnóstico por imagen
20.
Macromol Rapid Commun ; 45(4): e2300555, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38016789

RESUMEN

Molecularly imprinted polymer (L-MIP) for L-tyrosine (L-Tyr) is prepared by the complexation between quaternized poly(4-vinylpyridine/divinylbenzene) (QVP) and poly(acrylamide-co-acrylic acid) (PAmA) in alkaline solution. The L-MIP shows higher enantioselectivity for L-isomers of tyrosine, together with tryptophan (Trp) and phenylalanine (Phe) compared to the D-isomers of them. The sorption isotherms of the three D-enantiomers are converged to one isotherm. It can reflect that the sorption of D-enantiomers can be relied mainly on the common segment, -CH2 -CH(NH2 )-COOH, neglecting any effect of bulkier aromatic groups. The imprinted common segment can be opened on the surface of MIP from the D-enantiomers. For the L-enantiomers, the sorption discrepancies are depended on the size of the aromatic group implying that the phenolic moiety of L-Tyr can be also opened. Thus, the imprinted sites are proposed to be opened on the surface of L-MIP similar to the crop-circle-like. The enantioselectivity factors, αef  = QL /QD , for Tyr, Trp, and Phe are 1.52, 1.30, and 1.52 for L- to D-isomers, respectively. And the uptake differences between D- and L-enantiomers of Tyr, Trp, and Phe are 31.8, 20.7, and 29 mg per 1 g MIP, respectively.


Asunto(s)
Impresión Molecular , Triptófano , Fenilalanina , Polímeros Impresos Molecularmente , Tirosina , Estereoisomerismo
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