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1.
Cell ; 185(10): 1777-1792.e21, 2022 05 12.
Artículo en Inglés | MEDLINE | ID: mdl-35512705

RESUMEN

Spatially resolved transcriptomic technologies are promising tools to study complex biological processes such as mammalian embryogenesis. However, the imbalance between resolution, gene capture, and field of view of current methodologies precludes their systematic application to analyze relatively large and three-dimensional mid- and late-gestation embryos. Here, we combined DNA nanoball (DNB)-patterned arrays and in situ RNA capture to create spatial enhanced resolution omics-sequencing (Stereo-seq). We applied Stereo-seq to generate the mouse organogenesis spatiotemporal transcriptomic atlas (MOSTA), which maps with single-cell resolution and high sensitivity the kinetics and directionality of transcriptional variation during mouse organogenesis. We used this information to gain insight into the molecular basis of spatial cell heterogeneity and cell fate specification in developing tissues such as the dorsal midbrain. Our panoramic atlas will facilitate in-depth investigation of longstanding questions concerning normal and abnormal mammalian development.


Asunto(s)
Organogénesis , Transcriptoma , Animales , ADN/genética , Embrión de Mamíferos , Femenino , Perfilación de la Expresión Génica/métodos , Mamíferos/genética , Ratones , Organogénesis/genética , Embarazo , Análisis de Secuencia de ARN/métodos , Análisis de la Célula Individual/métodos , Transcriptoma/genética
2.
Nature ; 577(7791): 537-542, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31830756

RESUMEN

Our understanding of how human embryos develop before gastrulation, including spatial self-organization and cell type ontogeny, remains limited by available two-dimensional technological platforms1,2 that do not recapitulate the in vivo conditions3-5. Here we report a three-dimensional (3D) blastocyst-culture system that enables human blastocyst development up to the primitive streak anlage stage. These 3D embryos mimic developmental landmarks and 3D architectures in vivo, including the embryonic disc, amnion, basement membrane, primary and primate unique secondary yolk sac, formation of anterior-posterior polarity and primitive streak anlage. Using single-cell transcriptome profiling, we delineate ontology and regulatory networks that underlie the segregation of epiblast, primitive endoderm and trophoblast. Compared with epiblasts, the amniotic epithelium shows unique and characteristic phenotypes. After implantation, specific pathways and transcription factors trigger the differentiation of cytotrophoblasts, extravillous cytotrophoblasts and syncytiotrophoblasts. Epiblasts undergo a transition to pluripotency upon implantation, and the transcriptome of these cells is maintained until the generation of the primitive streak anlage. These developmental processes are driven by different pluripotency factors. Together, findings from our 3D-culture approach help to determine the molecular and morphogenetic developmental landscape that occurs during human embryogenesis.


Asunto(s)
Técnicas de Cultivo de Célula/métodos , Embrión de Mamíferos/citología , Embrión de Mamíferos/embriología , Desarrollo Embrionario , Línea Primitiva/citología , Línea Primitiva/embriología , Amnios/citología , Amnios/embriología , Blastocisto/citología , Diferenciación Celular , Linaje de la Célula , Polaridad Celular , Colágeno , Combinación de Medicamentos , Epitelio/embriología , Gastrulación , Estratos Germinativos/citología , Estratos Germinativos/embriología , Humanos , Laminina , Proteoglicanos , RNA-Seq , Análisis de la Célula Individual , Factores de Transcripción/metabolismo , Transcriptoma , Trofoblastos/citología , Saco Vitelino/citología , Saco Vitelino/embriología
3.
Neuroimage ; 285: 120472, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38007187

RESUMEN

Dynamic functional networks (DFN) have considerably advanced modelling of the brain communication processes. The prevailing implementation capitalizes on the system and network-level correlations between time series. However, this approach does not account for the continuous impact of non-dynamic dependencies within the statistical correlation, resulting in relatively stable connectivity patterns of DFN over time with limited sensitivity for communication dynamic between brain regions. Here, we propose an activation network framework based on the activity of functional connectivity (AFC) to extract new types of connectivity patterns during brain communication process. The AFC captures potential time-specific fluctuations associated with the brain communication processes by eliminating the non-dynamic dependency of the statistical correlation. In a simulation study, the positive correlation (r=0.966,p<0.001) between the extracted dynamic dependencies and the simulated "ground truth" validates the method's dynamic detection capability. Applying to autism spectrum disorders (ASD) and COVID-19 datasets, the proposed activation network extracts richer topological reorganization information, which is largely invisible to the DFN. Detailed, the activation network exhibits significant inter-regional connections between function-specific subnetworks and reconfigures more efficiently in the temporal dimension. Furthermore, the DFN fails to distinguish between patients and healthy controls. However, the proposed method reveals a significant decrease (p<0.05) in brain information processing abilities in patients. Finally, combining two types of networks successfully classifies ASD (83.636 % ± 11.969 %,mean±std) and COVID-19 (67.333 % ± 5.398 %). These findings suggest the proposed method could be a potential analytic framework for elucidating the neural mechanism of brain dynamics.


Asunto(s)
Trastorno del Espectro Autista , COVID-19 , Humanos , Imagen por Resonancia Magnética/métodos , Vías Nerviosas/fisiología , Encéfalo/fisiología , Mapeo Encefálico/métodos , Comunicación
4.
Ophthalmology ; 131(2): 179-187, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37709170

RESUMEN

PURPOSE: To determine early endophthalmitis incidence and risk factors after glaucoma surgeries in the Medicare population. DESIGN: Retrospective, longitudinal study. PARTICIPANTS: Medicare Fee-for-Service (FFS) and Medicare Advantage beneficiaries in the United States aged 65 years or older undergoing glaucoma surgery. METHODS: Medicare claims were used to identify all patients who underwent glaucoma, cataract, or combined cataract/glaucoma surgery from 2016 to 2019. Endophthalmitis cases within 42 days of the index surgery were identified using the diagnostic codes. Multivariable logistic regression models were used to evaluate factors associated with postoperative endophthalmitis. MAIN OUTCOME MEASURES: The 42-day postoperative endophthalmitis incidence and risk factors associated with endophthalmitis after glaucoma surgery. RESULTS: There were 466 928 glaucoma surgeries, of which 310 823 (66.6%) were combined with cataract surgery. Cataract surgeries alone (n = 8 460 360) served as a reference group. Microinvasive glaucoma surgeries constituted most glaucoma procedures performed (67.8%), followed by trabeculectomy (14.0%), tube shunt (10.9%), and other procedures (7.3%). There were 572 cases of endophthalmitis identified after all glaucoma surgeries. Endophthalmitis incidence after glaucoma, combined cataract/glaucoma, and cataract surgeries alone was 1.5 (95% confidence interval [CI], 1.3-1.7), 1.1 (95% CI, 1.0-1.2), and 0.8 (95% CI, 0.8-0.8) per 1000 procedures, respectively. The median day of diagnosis of endophthalmitis was later for glaucoma surgeries (16.5 days) compared with combined cataract/glaucoma or cataract surgeries alone (8 and 6 days, respectively). Compared with microinvasive glaucoma surgery (MIGS), tube shunts were the only surgery type to be a significant risk factor for endophthalmitis for both stand-alone (adjusted odds ratio [aOR], 1.8, P = 0.002) and combined surgery (aOR 1.8, P = 0.047). The other risk factor for both stand-alone (aOR 1.1, P = 0.001) and combined (aOR 1.06, P = 0.049) surgeries was the Charlson Comorbidity Index (CCI). Age (aOR 1.03, P = 0.004) and male gender (1.46, P = 0.001) were significant risk factors for combined cataract and glaucoma surgeries. CONCLUSIONS: Compared with cataract surgery, early endophthalmitis incidence was higher for both glaucoma and combined cataract/glaucoma surgeries, with the highest incidence among tube shunts. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.


Asunto(s)
Extracción de Catarata , Catarata , Endoftalmitis , Glaucoma , Humanos , Anciano , Masculino , Estados Unidos/epidemiología , Medicare , Estudios Retrospectivos , Incidencia , Estudios Longitudinales , Endoftalmitis/epidemiología , Endoftalmitis/etiología , Endoftalmitis/diagnóstico , Extracción de Catarata/efectos adversos , Factores de Riesgo , Catarata/complicaciones , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Glaucoma/epidemiología , Glaucoma/cirugía , Glaucoma/complicaciones
5.
Ecotoxicol Environ Saf ; 278: 116432, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38728947

RESUMEN

Cadmium (Cd) pollution is a serious global environmental problem, which requires a global concern and practical solutions. Microbial remediation has received widespread attention owing to advantages, such as environmental friendliness and soil amelioration. However, Cd toxicity also severely deteriorates the remediation performance of functional microorganisms. Analyzing the mechanism of bacterial resistance to Cd stress will be beneficial for the application of Cd remediation. In this study, the bacteria strain, up to 1400 mg/L Cd resistance, was employed and identified as Proteus mirabilis Ch8 (Ch8) through whole genome sequence analyses. The results indicated that the multiple pathways of immobilizing and detoxifying Cd maintained the growth of Ch8 under Cd stress, which also possessed high Cd extracellular adsorption. Firstly, the changes in surface morphology and functional groups of Ch8 cells were observed under different Cd conditions through SEM-EDS and FTIR analyses. Under 100 mg/L Cd, Ch8 cells exhibited aggregation and less flagella; the Cd biosorption of Ch8 was predominately by secreting exopolysaccharides (EPS) and no significant change of functional groups. Under 500 mg/L Cd, Ch8 were present irregular polymers on the cell surface, some cells with wrapping around; the Cd biosorption capacity exhibited outstanding effects (38.80 mg/g), which was mainly immobilizing Cd by secreting and interacting with EPS. Then, Ch8 also significantly enhanced the antioxidant enzyme activity and the antioxidant substance content under different Cd conditions. The activities of SOD and CAT, GSH content of Ch8 under 500 mg/L Cd were significantly increased by 245.47%, 179.52%, and 241.81%, compared to normal condition. Additionally, Ch8 significantly induced the expression of Acr A and Tol C (the resistance-nodulation-division (RND) efflux pump), and some antioxidant genes (SodB, SodC, and Tpx) to reduce Cd damage. In particular, the markedly higher expression levels of SodB under Cd stress. The mechanism of Ch8 lays a foundation for its application in solving soil remediation.


Asunto(s)
Cadmio , Proteus mirabilis , Contaminantes del Suelo , Cadmio/toxicidad , Contaminantes del Suelo/toxicidad , Biodegradación Ambiental
6.
Phys Rev Lett ; 131(4): 046601, 2023 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-37566870

RESUMEN

We report a topological phase transition in quantum-confined cadmium arsenide (Cd_{3}As_{2}) thin films under an in-plane Zeeman field when the Fermi level is tuned into the topological gap via an electric field. Symmetry considerations in this case predict the appearance of a two-dimensional Weyl semimetal (2D WSM), with a pair of Weyl nodes of opposite chirality at charge neutrality that are protected by space-time inversion (C_{2}T) symmetry. We show that the 2D WSM phase displays unique transport signatures, including saturated resistivities on the order of h/e^{2} that persist over a range of in-plane magnetic fields. Moreover, applying a small out-of-plane magnetic field, while keeping the in-plane field within the stability range of the 2D WSM phase, gives rise to a well-developed odd integer quantum Hall effect, characteristic of degenerate, massive Weyl fermions. A minimal four-band k·p model of Cd_{3}As_{2}, which incorporates first-principles effective g factors, qualitatively explains our findings.

7.
Clin Lab ; 69(9)2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37702689

RESUMEN

BACKGROUND: Anaplastic lymphoma kinase-positive (ALK+) large cell lymphoma (ALCL) is a systemic lymphoma. The invasion of the head and neck bone and skin by ALK+ ALCL is relatively uncommon in children. METHODS: We describe a 13-year-old boy diagnosed with ALK+ ALCL. RESULTS: He went a surgery of sampling biopsy procedure. Then the boy was treated with six cycles of adjuvant chemotherapy with Non-Hodgkin's Lymphoma-Berlin-Frankfurt-Munster (NHL-BFM)-90 K3 arm. Then, he achieved partial remission (PR). CONCLUSIONS: It is common for children to develop ALCL, which grows rapidly. Therefore, a sampling biopsy procedure and NHL-BFM-90 K3 were necessary for the patient.


Asunto(s)
Linfoma Anaplásico de Células Grandes , Masculino , Niño , Humanos , Adolescente , Linfoma Anaplásico de Células Grandes/diagnóstico , Linfoma Anaplásico de Células Grandes/tratamiento farmacológico , Quinasa de Linfoma Anaplásico , Biopsia , Cuello
8.
Sleep Breath ; 2023 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-37775619

RESUMEN

PURPOSE: Intermittent hypoxia (IH) is a hallmark of obstructive sleep apnea (OSA), which is related to tumorigenesis and progression. Although micro-ribonucleic acid-210-3p (miR-210-3p) is correlated with hypoxia-induced tumor development, its role in the relationship between IH and tumor function remains poorly understood. The present work focused on elucidating the molecular mechanism through which miR-210-3p drives tumor progression under IH. METHODS: MiR-210-3p levels were quantified within tumor samples from patients with lung adenocarcinoma who had or did not have OSA. Correlations between miR-210-3p and polysomnographic variables were analyzed. For in vitro experiments, miR-210-3p was inhibited or overexpressed via transfection under IH conditions. Cell viability, growth, invasion and migration assays were carried out. For in vivo modeling of IH using mouse xenografts, a miR-210-3p antagomir was intratumorally injected, tumor biological behaviors were evaluated, and reverse transcription-quantitative polymerase chain reaction (RT-qPCR), immunohistochemistry and western blot were carried out for detecting miR-210-3p and E2F transcription factor 3 (E2F3) expression. RESULTS: For patients with lung adenocarcinoma and OSA, high miR-210-3p levels showed positive relation to polysomnographic variables, such as oxygen desaturation index, apnea-hypopnea index, and proportion of total sleep time with oxygen saturation in arterial blood < 90%. IH enhanced tumor viability, proliferation, migration, and invasion, downregulated E2F3 expression, and increased miR-210-3-p levels. miR-210-3p overexpression induced similar changes. These changes were reversed by miR-210-3p inhibition in vitro or miR-210-3p antagomir through intratumoral injection in vivo. CONCLUSIONS: IH-induced tumor development is driven through miR-210-3p by E2F3 suppression. MiR-210-3p represents a potential therapeutic target among patients with concomitant cancer and OSA.

9.
Sensors (Basel) ; 23(1)2023 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-36617047

RESUMEN

For assembly of trans-scale micro-device capsule fill tube assemblies (CFTA) for inertial confinement fusion (ICF) targets, a high-precision space assembly approach based on micro-vision is proposed in this paper. The approach consists of three modules: (i) a posture alignment module based on a multi-vision monitoring model that is designed to align two trans-scale micro-parts in 5DOF while one micro-part is in ten microns and the other one is in hundreds of microns; (ii) an insertion depth control module based on a proposed local deformation detection method to control micro-part insertion depth; (iii) a glue mass control module based on simulation research that is designed to control glue mass quantitatively and to bond micro-parts together. A series of experiments were conducted and experimental results reveal that attitude alignment control error is less than ±0.3°, position alignment control error is less than ±5 µm, and insertion depth control error is less than ±5 µm. Deviation of glue spot diameter is controlled at less than 15 µm. A CFTA was assembled based on the proposed approach, the position error in 3D space measured by computerized tomography (CT) is less than 5 µm, and glue spot diameter at the joint is 56 µm. Through volume calculation by the cone calculation formula, the glue mass is about 23 PL when the cone height is half the diameter.


Asunto(s)
Tomografía Computarizada de Haz Cónico , Tomografía Computarizada de Haz Cónico/métodos , Microtomografía por Rayos X/métodos
10.
Phys Rev Lett ; 128(2): 026403, 2022 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-35089764

RESUMEN

We theoretically study the correlated insulator states, quantum anomalous Hall (QAH) states, and field-induced topological transitions between different correlated states in twisted multilayer graphene systems. Taking twisted bilayer-monolayer graphene and twisted double-bilayer graphene as examples, we show that both systems stay in spin-polarized, C_{3z}-broken insulator states with zero Chern number at 1/2 filling of the flat bands under finite displacement fields. In some cases these spin-polarized, nematic insulator states are in the quantum valley Hall (QVH) phase by virtue of the nontrivial band topology of the systems. The spin-polarized insulator state is quasidegenerate with the valley polarized state if only the dominant intravalley Coulomb interaction is included. Such quasidegeneracy can be split by atomic on-site interactions such that the spin-polarized, nematic state become the unique ground state. Such a scenario applies to various twisted multilayer graphene systems at 1/2 filling, thus can be considered as a universal mechanism. Moreover, under vertical magnetic fields, the orbital Zeeman splittings and the field-induced change of charge density in twisted multilayer graphene systems would compete with the atomic Hubbard interactions, which can drive transitions from spin-polarized zero-Chern-number states to valley-polarized QAH states with small onset magnetic fields.

11.
J Org Chem ; 87(13): 8437-8444, 2022 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-35679839

RESUMEN

An organocatalyzed, formal (3+3) cycloaddition reaction is described for the practical synthesis of substituted pyridines. Starting from readily available enamines and enal/ynal/enone substrates, the protocol affords tri- or tetrasubstituted pyridine scaffolds bearing various functional groups. This method was demonstrated on a 50 g scale, enabling the synthesis of 2-isopropyl-4-methylpyridin-3-amine, a raw material used for the manufacture of sotorasib. Mechanistic analysis using two-dimensional nuclear magnetic resonance (NMR) spectrometry revealed the transformation proceeds through the reversible formation of a stable reaction off-cycle species that precedes pyridine formation. In situ reaction progress kinetic analysis and control NMR studies were employed to better understand the role of FeCl3 and pyrrolidine hydrochloride in promoting the reaction.


Asunto(s)
Aldehídos , Cetonas , Aldehídos/química , Catálisis , Reacción de Cicloadición , Cetonas/química , Cinética , Piridinas/química
12.
Chem Soc Rev ; 50(19): 10733-10742, 2021 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-34382626

RESUMEN

Construction of new carbon-carbon bonds is the cornerstone of organic chemistry. Organometallic reagents are amongst the most robust and versatile nucleophiles for this purpose. Polarization of the metal-carbon bonds in these reagents facilitates their reactions with a vast array of electrophiles to achieve chemical diversification. The dependence on stoichiometric quantities of metals and often organic halides as feedstock precursors, which in turn produces copious amounts of metal halide waste, is the key limitation of the classical organometallic reactions. Inspired by the classical Wolff-Kishner reduction converting carbonyl groups in aldehydes or ketones into methylene derivatives, our group has recently developed strategies to couple various alcohols, aldehydes, and ketones with a broad range of both hard and soft carbon electrophiles in the presence of catalytic amounts of transition metals, via the hydrazone derivatives: i.e., as organometallic reagent surrogates. This Tutorial Review describes the chronological development of this concept in our research group, detailing its creation in the context of a deoxygenation reaction and evolution to a more general carbon-carbon bond-forming strategy. The latter is demonstrated by the employment of carbonyl-derived alkyl carbanions in various transition-metal catalyzed chemical transformations, including 1,2-carbonyl/imine addition, conjugate addition, carboxylation, olefination, cross-coupling, allylation, alkylation and hydroalkylation.

13.
Opt Express ; 29(21): 34126-34134, 2021 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-34809210

RESUMEN

High brightness Si nanocrystal white light-emitting diodes (WLED) based on differentially passivated silicon nanocrystals (SiNCs) are reported. The active layer was made by mixing freestanding SiNCs with hydrogen silsesquioxane, followed by annealing at moderately high temperatures, which finally led to a continuous spectral light emission covering red, green and blue regimes. The photoluminescence quantum yield (PLQY) of the active layer was 11.4%. The SiNC WLED was composed of a front electrode, electron transfer layer, front charge confinement layer, highly luminescent active layer, rear charge confinement layer, hole transfer layer, textured p-type Si substrate and aluminum rear electrode from top to bottom. The peak luminance of the SiNC WLED achieved was 2060 cd/m2. The turn-on voltage was 3.7 V. The chromaticity of the SiNC WLED indicated white light emission that could be adjusted by changing the annealing temperature of the active layer with color temperatures ranging from 3686 to 5291 K.

14.
Epilepsia ; 62(10): 2426-2438, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34346086

RESUMEN

OBJECTIVE: Seizure occurs when the balance between excitatory and inhibitory (E/I) inputs to neurons is perturbed, resulting in abnormal electrical activity. This study investigated whether an existing E/I imbalance in neural networks is a useful diagnostic biomarker for Rolandic epilepsy by a resting-state dynamic causal modeling-based support vector machine (rs-DCM-SVM) algorithm. METHODS: This multicenter study enrolled a discovery cohort (76 children with Rolandic epilepsy and 76 normal controls [NCs]) and a replication cohort (59 children with Rolandic epilepsy and 60 NCs). Spatial independent component analysis was used to seven canonical neural networks, and a total of 25 regions of interest were selected from these networks. The rs-DCM-SVM classifier was used for individual classification, consensus feature selection, and feature ranking. RESULTS: The rs-DCM-SVM classifier showed that the E/I imbalance in brain networks is a useful neuroimaging biomarker for Rolandic epilepsy, with an accuracy of 88.2% and 81.5% and an area under curve of .92 and .83 in the discovery and the replication cohorts, respectively. Consensus brain regions with the highest contributions to the classification were located within the epilepsy-related networks, indicating that this classifier was suitable. Consensus functional connection pairs with the highest contributions to the classification were associated with an excitation network loop and an inhibition network loop. The excitation loop mediated the integration of advanced cognitive networks (subcortex, dorsal attention, default mode, executive control, and salience networks), whereas the inhibition loop was involved in the segregation of sensorimotor and language networks. The two loops showed functional segregation. SIGNIFICANCE: Brain E/I imbalance has potential to serve as a biomarker for individual classification in children with Rolandic epilepsy, and might be an important mechanism for causing seizures and cognitive impairment in children with Rolandic epilepsy.


Asunto(s)
Epilepsia Rolándica , Biomarcadores , Encéfalo/diagnóstico por imagen , Niño , Electroencefalografía , Humanos , Imagen por Resonancia Magnética/métodos , Convulsiones , Máquina de Vectores de Soporte
15.
Nature ; 527(7579): 495-8, 2015 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-26607545

RESUMEN

Fermions--elementary particles such as electrons--are classified as Dirac, Majorana or Weyl. Majorana and Weyl fermions had not been observed experimentally until the recent discovery of condensed matter systems such as topological superconductors and semimetals, in which they arise as low-energy excitations. Here we propose the existence of a previously overlooked type of Weyl fermion that emerges at the boundary between electron and hole pockets in a new phase of matter. This particle was missed by Weyl because it breaks the stringent Lorentz symmetry in high-energy physics. Lorentz invariance, however, is not present in condensed matter physics, and by generalizing the Dirac equation, we find the new type of Weyl fermion. In particular, whereas Weyl semimetals--materials hosting Weyl fermions--were previously thought to have standard Weyl points with a point-like Fermi surface (which we refer to as type-I), we discover a type-II Weyl point, which is still a protected crossing, but appears at the contact of electron and hole pockets in type-II Weyl semimetals. We predict that WTe2 is an example of a topological semimetal hosting the new particle as a low-energy excitation around such a type-II Weyl point. The existence of type-II Weyl points in WTe2 means that many of its physical properties are very different to those of standard Weyl semimetals with point-like Fermi surfaces.

16.
Cardiovasc Diabetol ; 19(1): 71, 2020 05 30.
Artículo en Inglés | MEDLINE | ID: mdl-32473648

RESUMEN

BACKGROUND: Postprandial hyperglycemia was reported to play a key role in established risk factors of coronary artery diseases (CAD) and cardiovascular events. Serum 1,5-anhydroglucitol (1,5-AG) levels are known to be a clinical marker of short-term postprandial glucose (PPG) excursions. Low serum 1,5-AG levels have been associated with occurrence of CAD. However, the relationship between 1,5-AG levels and coronary plaque rupture has not been fully elucidated. The aim of this study was to evaluate 1,5-AG as a predictor of coronary plaque rupture in diabetic patients with acute coronary syndrome (ACS). METHODS: A total of 144 diabetic patients with ACS were included in this study. All patients underwent intravascular ultrasound examination, which revealed 49 patients with plaque rupture and 95 patients without plaque rupture in the culprit lesion. Fasting blood glucose (FBG), hemoglobin A1c (HbA1c) and 1,5-AG levels were measured before coronary angiography. Fasting urinary 8-iso-prostaglandin F2α (8-iso-PGF2α) level was measured and corrected by creatinine clearance. RESULTS: Patients with ruptured plaque had significantly lower serum 1,5-AG levels, longer duration of diabetes, higher HbA1c and FBG levels than patients without ruptured plaque in our study population. In multivariate analysis, low 1,5-AG levels were an independent predictor of plaque rupture (odds ratio 3.421; P = 0.005) in diabetic patients with ACS. The area under the receiver-operating characteristic curve for 1,5-AG (0.658, P = 0.002) to predict plaque rupture was superior to that for HbA1c (0.587, P = 0.087). Levels of 1,5-AG were significantly correlated with urinary 8-iso-prostaglandin F2α levels (r = - 0.234, P = 0.005). CONCLUSIONS: Serum 1,5-AG may identify high risk for coronary plaque rupture in diabetic patients with ACS, which suggests PPG excursions are related to the pathogenesis of plaque rupture in diabetes.


Asunto(s)
Síndrome Coronario Agudo/sangre , Enfermedad de la Arteria Coronaria/sangre , Vasos Coronarios/diagnóstico por imagen , Desoxiglucosa/sangre , Diabetes Mellitus Tipo 2/sangre , Placa Aterosclerótica , Ultrasonografía Intervencional , Síndrome Coronario Agudo/diagnóstico por imagen , Síndrome Coronario Agudo/orina , Anciano , Biomarcadores/sangre , Biomarcadores/orina , Glucemia/metabolismo , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/orina , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/orina , Dinoprost/análogos & derivados , Dinoprost/orina , Femenino , Hemoglobina Glucada/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Prospectivos , Rotura Espontánea
17.
Phys Rev Lett ; 124(7): 076403, 2020 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-32142316

RESUMEN

Exploration of the novel relationship between magnetic order and topological semimetals has received enormous interest in a wide range of both fundamental and applied research. Here we predict that "soft" ferromagnetic material EuB_{6} can achieve multiple topological semimetal phases by simply tuning the direction of the magnetic moment. Explicitly, EuB_{6} is a topological nodal-line semimetal when the moment is aligned along the [001] direction, and it evolves into a Weyl semimetal with three pairs of Weyl points by rotating the moment to the [111] direction. Interestingly, we identify a composite semimetal phase featuring the coexistence of a nodal line and Weyl points with the moment in the [110] direction. Topological surface states and anomalous Hall conductivity, which are sensitive to the magnetic order, have been computed and are expected to be experimentally observable. Large-Chern-number quantum anomalous Hall effect can be realized in its [111]-oriented quantum-well structures.

18.
Phys Rev Lett ; 124(23): 239902, 2020 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-32603163

RESUMEN

This corrects the article DOI: 10.1103/PhysRevLett.117.056805.

19.
Retina ; 40(9): 1783-1792, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31584558

RESUMEN

PURPOSE: To determine the ability of nonperfusion, vessel density, and morphologic measurements using projection-resolved optical coherence tomography angiography to detect early retinal microvasculature impairments in diabetes mellitus. METHODS: A retrospective review was performed on Type 2 diabetes mellitus patients with no diabetic retinopathy (DR) or mild nonproliferative DR and age-matched controls imaged with optical coherence tomography angiography. Foveal avascular zone-related metrics and extrafoveal avascular area were measured in optical coherence tomography angiography images. Vessel density and fractal dimension were calculated with and without a skeletonization process. The vessel diameter index and vessel tortuosity were computed. The area under the receiver operating characteristic curve (AUC) estimated diagnostic performances. RESULTS: Dilated capillary diameter was observed in the deep capillary plexus in the diabetic groups. Vessel density and fractal dimension of skeletonized deep capillary plexus significantly and progressively decreased in the no DR and mild nonproliferative DR groups compared with controls. Superficial extrafoveal avascular area, vessel density, and fractal dimension of the skeletonized deep capillary plexus had the highest diagnostic performance to differentiate mild nonproliferative DR from control eyes, with AUCs of 0.885, 0.876, and 0.876, respectively. CONCLUSION: Vessel density and fractal dimension from the skeletonized deep capillary network may be the most sensitive for detecting early retinal capillary loss in diabetes mellitus.


Asunto(s)
Diabetes Mellitus Tipo 2/diagnóstico , Retinopatía Diabética/diagnóstico , Vasos Retinianos/patología , Anciano , Área Bajo la Curva , Diabetes Mellitus Tipo 2/fisiopatología , Retinopatía Diabética/fisiopatología , Diagnóstico Precoz , Femenino , Angiografía con Fluoresceína , Fóvea Central/irrigación sanguínea , Humanos , Masculino , Microvasos/patología , Persona de Mediana Edad , Curva ROC , Vasos Retinianos/diagnóstico por imagen , Estudios Retrospectivos , Tomografía de Coherencia Óptica
20.
Nano Lett ; 19(3): 1736-1742, 2019 03 13.
Artículo en Inglés | MEDLINE | ID: mdl-30720286

RESUMEN

Two-dimensional transition metal dichalcogenides (TMDCs) are recently emerged electronic systems with various novel properties, such as spin-valley locking, circular dichroism, valley Hall effect, and superconductivity. The reduced dimensionality and large effective masses further produce unconventional many-body interaction effects. Here we reveal strong interaction effects in the conduction band of MoS2 by transport experiment. We study the massive Dirac electron Landau levels (LL) in high-quality MoS2 samples with field-effect mobilities of 24 000 cm2/(V·s) at 1.2 K. We identify the valley-resolved LLs and low-lying polarized LLs using the Lifshitz-Kosevitch formula. By further tracing the LL crossings in the Landau fan diagram, we unambiguously determine the density-dependent valley susceptibility and the interaction enhanced g-factor from 12.7 to 23.6. Near integer ratios of Zeeman-to-cyclotron energies, we discover LL anticrossings due to the formation of quantum Hall Ising ferromagnets, the valley polarizations of which appear to be reversible by tuning the density or an in-plane magnetic field. Our results provide evidence for many-body interaction effects in the conduction band of MoS2 and establish a fertile ground for exploring strongly correlated phenomena of massive Dirac electrons.

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