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1.
BMC Cardiovasc Disord ; 24(1): 178, 2024 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-38521897

RESUMEN

AIMS: The current management of patients with atrial fibrillation (AF) and concomitant heart failure (HF) remains a significant challenge. Catheter ablation (CA) has been shown to improve left ventricular ejection fraction (LVEF) in these patients, but which patients can benefit from CA is still poorly understood. The aim of our study was to determine the predictors of improved ejection fraction in patients with persistent atrial fibrillation (PeAF) complicated with HF undergoing CA. METHODS AND RESULTS: A total of 435 patients with persistent AF underwent an initial CA between January 2019 and March 2023 in our hospital. We investigated consecutive patients with left ventricular systolic dysfunction (LVEF < 50%) measured by transthoracic echocardiography (TTE) within one month before CA. According to the LVEF changes at 6 months, these patients were divided into an improved group (fulfilling the '2021 Universal Definition of HF' criteria for LVEF recovery) and a nonimproved group. Eighty patients were analyzed, and the improvement group consisted of 60 patients (75.0%). In the univariate analysis, left ventricular end-diastolic diameter (P = 0.005) and low voltage zones in the left atrium (P = 0.043) were associated with improvement of LVEF. A receiver operating characteristic analysis determined that the suitable cutoff value for left ventricular end-diastolic diameter (LVDd) was 59 mm (sensitivity: 85.0%, specificity: 55.0%, area under curve: 0.709). A multivariate analysis showed that LVDd (OR = 0.85; 95% CI: 0.76-0.95, P = 0.005) and low voltage zones (LVZs) (OR = 0.26; 95% CI: 0.07-0.96, P = 0.043) were significantly independently associated with the improvement of LVEF. Additionally, parameters were significantly improved regarding the left atrial diameter, LVDd and ventricular rate after radiofrequency catheter ablation (all p < 0.05). CONCLUSIONS: The improvement of left ventricular ejection fraction (LVEF) occurred in 75.0% of patients. Our study provides additional evidence that LVDd < 59 mm and no low voltage zones in the left atrium can be used to jointly predict the improvement of LVEF after atrial fibrillation ablation.


Asunto(s)
Fibrilación Atrial , Ablación por Catéter , Insuficiencia Cardíaca , Disfunción Ventricular Izquierda , Humanos , Fibrilación Atrial/diagnóstico , Fibrilación Atrial/cirugía , Fibrilación Atrial/complicaciones , Función Ventricular Izquierda , Volumen Sistólico , Insuficiencia Cardíaca/diagnóstico por imagen , Insuficiencia Cardíaca/complicaciones , Disfunción Ventricular Izquierda/etiología , Disfunción Ventricular Izquierda/complicaciones , Ablación por Catéter/efectos adversos , Ablación por Catéter/métodos , Resultado del Tratamiento
2.
Phys Rev Lett ; 130(15): 153202, 2023 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-37115898

RESUMEN

We report optical trapping of a polyatomic molecule, calcium monohydroxide (CaOH). CaOH molecules from a magneto-optical trap are sub-Doppler laser cooled to 20(3) µK in free space and loaded into an optical dipole trap. We attain an in-trap molecule number density of 3(1)×10^{9} cm^{-3} at a temperature of 57(8) µK. Trapped CaOH molecules are optically pumped into an excited vibrational bending mode, whose ℓ-type parity doublet structure is a potential resource for a wide range of proposed quantum science applications with polyatomic molecules. We measure the spontaneous, radiative lifetime of this bending mode state to be ∼0.7 s.

3.
J Magn Reson Imaging ; 58(1): 135-144, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36326149

RESUMEN

BACKGROUND: Left atrial (LA) strain is associated with structural remodeling of the LA. Whether there is an association between LA strain obtained by cardiac magnetic resonance imaging (MRI) and new-onset atrial fibrillation (AF) after ST-segment elevation myocardial infarction (STEMI) is unclear. PURPOSE: To investigate the relationship between LA strain and new-onset AF after STEMI. STUDY TYPE: Retrospective. POPULATION: Three hundred and seventy-nine STEMI patients were enrolled, of which 26 had new-onset AF. FIELD STRENGTH/SEQUENCE: 3.0 T, balanced turbo field echo sequence. ASSESSMENT: Patients were divided into w/o AF group and new-onset AF group. Cardiac MRI images were analyzed using cardiovascular imaging software CVI 42 (Circle Cardiovascular Imaging, Canada). An automatic tracing algorithm was applied to obtain strain values. The reservoir strain, conduit strain, and booster strain were included in model 1, model 2, and model 3, respectively. STATISTICAL TESTS: Student's t-test, Mann-Whiney U test, and chi-square test were performed. Variables with a P ≤ 0.05 were incorporated into the logistic regression analysis. Area under curve of receiver operating characteristic was used to assess the ability of LA strain to identify new-onset AF. Bayesian information criterion, Akaike information criterion, and C-index were used to make comparisons between three models. P < 0.05 was considered statistically significant. RESULTS: Three models were used to assess LA strain identification ability for new-onset AF. After including multiple factors, right coronary artery (RCA), LVEF, and reservoir strain were still risk factors for new-onset AF in model 1. In model 2, age, RCA, LVEF, and conduit strain were still risk factors for new-onset AF. In model 3, RCA, LVEF, LVEDVi, and booster strain were still risk factors for new-onset AF. Model 2 has a stronger identification ability than others. DATA CONCLUSION: LA strain associated with new-onset AF after STEMI. The model including conduit strain was the best-fit one. LEVEL OF EVIDENCE: 4 TECHNICAL EFFICACY: Stage 3.


Asunto(s)
Fibrilación Atrial , Infarto del Miocardio con Elevación del ST , Humanos , Fibrilación Atrial/complicaciones , Fibrilación Atrial/diagnóstico por imagen , Infarto del Miocardio con Elevación del ST/diagnóstico por imagen , Infarto del Miocardio con Elevación del ST/complicaciones , Infarto del Miocardio con Elevación del ST/patología , Estudios Retrospectivos , Teorema de Bayes , Valor Predictivo de las Pruebas , Atrios Cardíacos/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos
4.
Ann Bot ; 131(7): 1097-1106, 2023 08 25.
Artículo en Inglés | MEDLINE | ID: mdl-36661261

RESUMEN

BACKGROUND AND AIMS: The abundance or decline of fern populations in response to environmental change has been found to be largely dependent on specific physiological properties that distinguish ferns from angiosperms. Many studies have focused on water use efficiency and stomatal behaviours, but the effects of nutrition acquirement and utilization strategies on niche competition between ferns and flowering plants are rarely reported. METHODS: We collected 34 ferns and 42 angiosperms from the Botanic Garden of Hokkaido University for nitrogen (N), sulphur (S), NO3- and SO42- analysis. We then used a hydroponic system to compare the different N and S utilization strategies between ferns and angiosperms under N deficiency conditions. KEY RESULTS: Ferns had a significantly higher NO3--N concentration and NO3--N/N ratio than angiosperms, although the total N concentration in ferns was remarkably lower than that in the angiosperms. Meanwhile, a positive correlation between N and S was found, indicating that nutrient concentration is involved in assimilation. Pteris cretica, a fern species subjected to further study, maintained a slow growth rate and lower N requirement in response to low N stress, while both the biomass and N concentration in wheat (Triticum aestivum) responded quickly to N deficiency conditions. CONCLUSIONS: The different nutritional strategies employed by ferns and angiosperms depended mainly on the effects of phylogenetic and evolutionary diversity. Ferns tend to adopt an opportunistic strategy of limiting growth rate to reduce N demand and store more pooled nitrate, whereas angiosperms probably utilize N nutrition to ensure as much development as possible under low N stress. Identifying the effects of mineral nutrition on the evolutionary results of ecological competition between plant species remains a challenge.


Asunto(s)
Helechos , Magnoliopsida , Magnoliopsida/fisiología , Filogenia , Helechos/fisiología , Evolución Biológica , Triticum
5.
Artículo en Inglés | MEDLINE | ID: mdl-37160503

RESUMEN

CONTEXT: A nomogram model affecting the activated clotting time (ACT) targeting rate during radiofrequency ablation of atrial fibrillation (RFCA) in China. PURPOSE: The aim of this study is to develop and validate a nomogram model for predicting the activated clotting time targeting rate after the initial bolus heparin dosages during the radiofrequency catheter ablation of atrial fibrillation in China. METHODS AND RESULTS: A retrospective observational study was conducted on the data of 465 patients with atrial fibrillation who underwent radiofrequency catheter ablation (RFCA) from October 2019 to June 2022. All patients were randomized into a training cohort (70%; n = 325) and a validation cohort (30%; n = 140). Independent risk factors were identified using univariate and multifactorial logistic regression analysis. The predictive nomogram model was established using R software. The nomogram was developed and evaluated based on differentiation, calibration, and clinical efficacy using concordance statistic (C-statistic), calibration plots, and decision curve analysis (DCA), respectively. The nomogram was established using three variables, including sex (OR 1.01, 95% CI 0.29-1.76, P = 0.007), heparin dose (OR 0.04; 95%CI 0.02-0.05, P < 0.001), and the baseline ACT (OR 0.03; 95%CI 0.02-0.04, P < 0.001). The C-statistic of the nomogram was 0.736 (95%CI 0.675-0.732) in the training cohort and 0.700 (95%CI 0.622-0.721) in the validation cohort. The calibration plots showed good agreement between the predictions and observations in the training and validation cohorts. The clinical decision curve also proves that the map is useful in clinical settings. CONCLUSION: The nomogram model has good discrimination and accuracy, which can screen attainment groups intuitively and individually, and has a certain predictive value for the probability of ACT reaching the target after the adequate dosage of initial heparin in Chinese patients with atrial fibrillation.

6.
Artículo en Inglés | MEDLINE | ID: mdl-38103153

RESUMEN

BACKGROUND: The objective of this study is to establish and validate a nomogram model for predicting the probability of silent cerebral infarction following ablation of atrial fibrillation. METHODS AND RESULTS: A retrospective observational study was conducted on the data of 238 patients with atrial fibrillation who underwent radiofrequency ablation in our hospital from October 2019 to December 2022. LASSO regression and multivariate logistics regression analysis were used to assess the independent risk factors for silent cerebral infarction after ablation. The AUC of the predictive model was 0.733 (95% CI, 0.649-0.816) and the internal validation (bootstrap = 1000) of the bootstrap method was 0.733 (95% CI 0.646-0.813). The Hosmer-Lemeshow test yields an insignificant p-value of X-squared = 10.212 and p-value = 0.2504, thus indicating an insignificant difference between predicted and observed values and good calibration results. The clinical impact curve (CIC) and clinical decision curve also prove that this graph is useful in the clinical setting. CONCLUSION: We developed an easy-to-use nomogram model to predict the probability of silent cerebral infarction following radiofrequency ablation of atrial fibrillation. This model can provide a valid assessment of the probability of postoperative silent cerebral infarction in patients undergoing radiofrequency ablation of atrial fibrillation.

7.
Phys Chem Chem Phys ; 25(47): 32613-32621, 2023 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-38009218

RESUMEN

A relativistic coupled-cluster study of the low-lying electronic states in the radium monohydroxide molecule (RaOH), a radioactive polyatomic molecule of interest to laser cooling and to the search of new physics beyond the Standard Model, is reported. The level positions of the A2Π1/2 and C2Σ states have been computed with an accuracy of around 200 cm-1 to facilitate spectroscopic observation of RaOH using laser induced fluorescence spectroscopy, thereby exploiting the systematic convergence of electron-correlation and basis-set effects in relativistic coupled-cluster calculations. The energy level for the B2Δ3/2 state has also been calculated accurately to conclude that the B2Δ3/2 state lies above the A2Π1/2 state. This confirms X2Σ â†” A2Π1/2 as a promising optical cycling transition for laser cooling RaOH.

8.
J Chem Phys ; 159(24)2023 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-38153147

RESUMEN

A first implementation of analytic gradients for spinor-based relativistic equation-of-motion coupled-cluster singles and doubles method using an exact two-component Hamiltonian augmented with atomic mean-field spin-orbit integrals is reported. To demonstrate its applicability, we present calculations of equilibrium structures and harmonic vibrational frequencies for the electronic ground and excited states of the radium mono-amide molecule (RaNH2) and the radium mono-methoxide molecule (RaOCH3). Spin-orbit coupling is shown to quench Jahn-Teller effects in the first excited state of RaOCH3, resulting in a C3v equilibrium structure. The calculations also show that the radium atoms in these molecules serve as efficient optical cycling centers.

9.
J Nanobiotechnology ; 21(1): 483, 2023 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-38104180

RESUMEN

Salmonellosis is a globally extensive food-borne disease, which threatens public health and results in huge economic losses in the world annually. The rising prevalence of antibiotic resistance in Salmonella poses a significant global concern, emphasizing an imperative to identify novel therapeutic agents or methodologies to effectively combat this predicament. In this study, self-assembly hydrogen sulfide (H2S)-responsive nanoprodrugs were fabricated with poly(α-lipoic acid)-polyethylene glycol grafted rhein and geraniol (PPRG), self-assembled into core-shell nanoparticles via electrostatic, hydrophilic and hydrophobic interactions, with hydrophilic exterior and hydrophobic interior. The rhein and geraniol are released from self-assembly nanoprodrugs PPRG in response to Salmonella infection, which is known to produce hydrogen sulfide (H2S). PPRG demonstrated stronger antibacterial activity against Salmonella compared with rhein or geraniol alone in vitro and in vivo. Additionally, PPRG was also able to suppress the inflammation and modulate gut microbiota homeostasis. In conclusion, the as-prepared self-assembly nanoprodrug sheds new light on the design of natural product active ingredients and provides new ideas for exploring targeted therapies for specific Enteropathogens. Graphical  illustration for construction of self-assembly nanoprodrugs PPRG and its antibacterial and anti-inflammatory activities on experimental Salmonella infection in mice.


Asunto(s)
Sulfuro de Hidrógeno , Infecciones por Salmonella , Animales , Ratones , Salmonella typhimurium , Sulfuro de Hidrógeno/química , Infecciones por Salmonella/tratamiento farmacológico , Infecciones por Salmonella/microbiología , Antibacterianos/farmacología
10.
Environ Microbiol ; 24(11): 5019-5038, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35726890

RESUMEN

Magnetotactic bacteria (MTB) biomineralize intracellular magnetic nanocrystals and swim along geomagnetic field lines. While few axenic MTB cultures exist, living cells can be separated magnetically from natural environments for analysis. The bacterial universal 27F/1492R primer pair has been used widely to amplify nearly full-length 16S rRNA genes and to provide phylogenetic portraits of MTB communities. However, incomplete coverage and amplification biases inevitably prevent detection of some phylogenetically specific or non-abundant MTB. Here, we propose a new formulation of the upstream 390F primer that we combined with the downstream 1492R primer to specifically amplify 1100-bp 16S rRNA gene sequences of sulfate-reducing MTB in freshwater sediments from Lake Weiyanghu, Xi'an, northwestern China. With correlative fluorescence in situ hybridization and scanning/transmission electron microscopy, three novel MTB strains (WYHR-2, WYHR-3 and WYHR-4) from the Desulfobacterota phylum were identified phylogenetically and structurally at the single-cell level. Strain WYHR-2 produces bullet-shaped magnetosome magnetite, while the other two strains produce both cubic/prismatic greigite and bullet-shaped magnetite. Our results expand knowledge of bacterial diversity and magnetosome biomineralization of sulfate-reducing MTB. We also propose a general strategy for identifying and characterizing uncultured MTB from natural environments.


Asunto(s)
Desulfovibrio , Magnetosomas , ARN Ribosómico 16S/genética , ADN Ribosómico/genética , Sulfatos/análisis , Filogenia , Óxido Ferrosoférrico/análisis , Hibridación Fluorescente in Situ , Magnetosomas/genética , Magnetosomas/química , Lagos/microbiología , Microscopía Electrónica , Desulfovibrio/genética
11.
Phys Chem Chem Phys ; 24(22): 13587-13596, 2022 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-35616685

RESUMEN

A benchmark computational study of K-edge core-ionization energies of third-row elements using relativistic delta-coupled-cluster (ΔCC) methods and a revised core-valence separation (CVS) scheme is reported. High-level relativistic (HLR) corrections beyond the spin-free exact two-component theory in its one-electron variant (SFX2C-1e), including the contributions from two-electron picture-change effects, spin-orbit coupling, the Breit term, and quantum electrodynamics effects, have been taken into account and demonstrated to play an important role. Relativistic ΔCC calculations are shown to provide accurate results for core-ionization energies of third-row elements. The SFX2C-1e-CVS-ΔCC results augmented with HLR corrections show a maximum deviation of less than 0.5 eV with respect to experimental values.

12.
J Phys Chem A ; 126(27): 4537-4553, 2022 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-35763592

RESUMEN

An extension of the exact two-component theory with atomic mean-field integrals (the X2CAMF scheme) to the treatment of the Breit term together with efficient implementation using an atomic Dirac-Coulomb-Breit Hartree-Fock program is reported. The accuracy of the X2CAMF scheme for treating the contributions from the Breit term to the molecular properties is demonstrated using benchmark calculations of equilibrium bond lengths, harmonic frequencies, and dipole moments for molecules containing elements across the periodic table. Calculations of the properties for molecules containing period four elements aiming at high accuracy as well as for Th- and U-containing molecules are also presented and compared with experimental results to demonstrate the usefulness of the X2CAMF scheme in combination with accurate treatments of electron correlation by the coupled-cluster (CC) methods. The combination of CC methods and the X2CAMF scheme shows potential to extend the accuracy of CC calculations to heavy elements, e.g., to computational heavy-element thermochemistry.

13.
J Chem Phys ; 156(15): 151101, 2022 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-35459315

RESUMEN

Development of analytic gradients for relativistic coupled-cluster singles and doubles augmented with a non-iterative triples [CCSD(T)] method using an all-electron exact two-component Hamiltonian with atomic mean-field spin-orbit integrals (X2CAMF) is reported. This enables efficient CC geometry optimizations with spin-orbit coupling included in orbitals. The applicability of the implementation is demonstrated using benchmark X2CAMF-CCSD(T) calculations of equilibrium structures and harmonic vibrational frequencies for methyl halides, CH3X (X = Br, I, and At), as well as calculations of rotational constants and infrared spectrum for RaSH+, a radioactive molecular ion of interest to spectroscopic study.

14.
Drug Dev Res ; 83(6): 1455-1466, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35862278

RESUMEN

The aim of this study was to elucidate the mechanism underlying the effects of Kukoamine A (KuA) treatment on endotoxin-induced lung injury/inflammation. The study was performed in lipopolysaccharide (LPS)-exposed mouse models of lung injury and LPS-induced alveolar epithelial cell model. Relevant kits were used to detect levels of inflammation-related indicators, oxidative stress indicators, and mitochondrial function. Hematoxylin and eosin staining was to detect lung injury. Then, C-C motif chemokine receptor 5 (CCR5) overexpression plasmid was transfected into alveolar epithelial cells to investigate the mechanism of KuA in lung injury. The results showed that LPS induction increased the expression of inflammatory factors, oxidative stress markers, and mitochondrial dysfunction in both animal and cellular models. In the mouse model, KuA treatment improved lung tissue injury, decreased wet-to-dry ratio and MPO levels, reduced the expression of inflammatory factors, and ameliorated oxidative stress and mitochondrial dysfunction. The protective effect of KuA in the cell model remained whereas was markedly reversed after CCR5 overexpression. Taken together, KuA might improve LPS-induced lung injury by inhibiting CCR5. This might also provide a novel theory for KuA in the treatment of lung injury.


Asunto(s)
Lesión Pulmonar Aguda , Receptores de Quimiocina , Espermina , Lesión Pulmonar Aguda/inducido químicamente , Lesión Pulmonar Aguda/tratamiento farmacológico , Animales , Modelos Animales de Enfermedad , Inflamación , Lipopolisacáridos , Pulmón , Ratones , Estrés Oxidativo , Receptores CCR5 , Receptores de Quimiocina/antagonistas & inhibidores , Espermina/análogos & derivados , Espermina/farmacología
15.
J Environ Manage ; 303: 114167, 2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-34861505

RESUMEN

In recent decades, rapid urbanization and intensified global climate change have resulted in a significant difference of environment and resources distribution on space, which would cause trouble for accurate assessment of regional ecological sustainable development, especially in the large urban agglomerations. The parameters used in previous assessment methods have normally ignored spatial heterogeneity, leading to deviations in the evaluation accuracies against the context above. By incorporating remote sensing technology, this study proposed an improved emergy ecological footprint (EEF) method and a novel ecological sustainability index to comprehensively analyze the variability of ecological security states (ESS) from 1994 to 2018 in the Guangdong-Hong Kong-Macao Greater Bay Area (GBA) and to predict its sustainable growth potential based on a combined factorial decomposition and scenario analysis. Results showed that the pixel-based emergy analysis revealed significant heterogeneity over time and space under the impact of climate change and intense land use activities during the study period. The emergy carrying capacity per capita (ecc) and the emergy ecological footprint per capita (eef) also showed a significant difference between the nine cities in the GBA. In addition, the traditional EEF method, which does not consider the spatiotemporal variation, has indeed overestimated the GBA's ecc by 15% compared with our results. The ESS of the GBA gradually worsened from slight insecurity in the 1990s to moderate insecurity in 2018. If the current trends in socio-economic activities and climate change continue according to the RCP8.5 scenario in the IPCC, the ESS of the GBA will reach the extreme insecurity state in 2050. However, our scenarios show that industrial structure adjustment, energy structure optimization, and especially biological resource conservation can reduce the EFI by approximately 6.52%, 23.4%, and 30.6%, respectively. Consequently, effective implementation of the above measures can limit the increase both in emergy ecological deficit and emergy ecological footprint intensity (EFI) and, together, contribute to a higher security status in the GBA in 2050.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , China , Hong Kong , Macao , Estudios Prospectivos , Estudios Retrospectivos
16.
J Am Chem Soc ; 143(20): 7688-7697, 2021 05 26.
Artículo en Inglés | MEDLINE | ID: mdl-33983734

RESUMEN

Methylation of DNA at CpG sites is a major mark for epigenetic regulation, but how transcription factors are influenced by CpG methylation is not well understood. Here, we report the molecular mechanisms of how the TCF (T-cell factor) and GEF (glucose transporter 4 enhancer factor) families of proteins selectively target unmethylated DNA sequences with a C-clamp type zinc finger domain. The structure of the C-clamp domain from human GEF family protein HDBP1 (C-clampHDBP1) in complex with DNA was determined using NMR spectroscopy, which adopts a unique zinc finger fold and selectively binds RCCGG (R = A/G) DNA sequences with an "Arg···Trp-Lys-Lys" DNA recognition motif inserted in the major groove. The CpG base pairs are central to the binding due to multiple hydrogen bonds formed with the backbone carbonyl groups of Trp378 and Lys379, as well as the side chain ε-amino groups of Lys379 and Lys380 from C-clampHDBP1. Consequently, methylation of the CpG dinucleotide almost abolishes the binding. Homology modeling reveals that the C-clamp domain from human TCF1E (C-clampTCF1E) binds DNA through essentially the same mechanism, with a similar "Arg···Arg-Lys-Lys" DNA recognition motif. The substitution of tryptophan by arginine makes C-clampHDBP1 prefer RCCGC DNA sequences. The two signature DNA recognition motifs are invariant in the GEF and TCF families of proteins, respectively, from fly to human. The recognition of the CpG dinucleotide through two consecutive backbone carbonyl groups is the same as that of the CXXC type unmethylated CpG DNA binding domains, suggesting a common mechanism shared by unmethylated CpG binding proteins.


Asunto(s)
Cisteína/química , ADN/química , Islas de CpG , Humanos
17.
BMC Cardiovasc Disord ; 21(1): 442, 2021 09 16.
Artículo en Inglés | MEDLINE | ID: mdl-34530731

RESUMEN

BACKGROUND: Thromboembolic events are the most serious complication of atrial fibrillation (AF), and the left atrial appendage (LAA) is the most important site of thrombosis in patients with AF. During the period of COVID-19, a non-invasive left atrial appendage detection method is particularly important in order to reduce the exposure of the virus. This study used CT three-dimensional reconstruction methods to explore the relationship between LAA morphology, LAA orifice area and its mechanical function in patients with non-valvular atrial fibrillation (NVAF). METHODS: A total of 81 consecutive patients with NVAF (36 cases of paroxysmal atrial fibrillation and 45 cases of persistent atrial fibrillation) who were planned to undergo catheter radiofrequency ablation were enrolled. All patients were examined by transthoracic echocardiography (TTE), TEE, and computed tomography angiography (CTA) before surgery. The LAA orifice area was obtained according to the images of CTA. According to the left atrial appendage morphology, it was divided into chicken wing type and non-chicken wing type. At the same time, TEE was performed to determine left atrial appendage flow velocity (LAAFV), and the relationship between the left atrial appendage orifice area and LAAFV was analyzed. RESULTS: The LAAFV in Non-chicken wing group was lower than that in Chicken wing group (36.2 ± 15.0 cm/s vs. 49.1 ± 22.0 cm/s, p-value < 0.05). In the subgroup analysis, the LAAFV in Non-chicken wing group was lower than that in Chicken wing group in the paroxysmal AF (44.0 ± 14.3 cm/s vs. 60.2 ± 22.8 cm/s, p-value < 0.05). In the persistent AF, similar results were observed (29.7 ± 12.4 cm/s vs. 40.8 ± 17.7 cm/s, p-value < 0.05). The LAAFV in persistent AF group was lower than that in paroxysmal AF group (34.6 ± 15.8 cm/s vs. 49.9 ± 20.0 cm/s, p-value < 0.001). The LAAFV was negatively correlated with left atrial dimension (R = - 0.451, p-value < 0.001), LAA orifice area (R= - 0.438, p-value < 0.001) and left ventricular mass index (LVMI) (R= - 0.624, p-value < 0.001), while it was positively correlated with LVEF (R = 0.271, p-value = 0.014). Multiple linear regression analysis showed that LAA morphology (ß = - 0.335, p-value < 0.001), LAA orifice area (ß = - 0.185, p-value = 0.033), AF type (ß = - 0.167, p-value = 0.043) and LVMI (ß = - 0.465, p-value < 0.001) were independent factors of LAAFV. CONCLUSIONS: The LAA orifice area is closely related to the mechanical function of the LAA in patients with NVAF. The larger LAA orifice area and LVMI, Non-chicken wing LAA and persistent AF are independent predictors of decreased mechanical function of LAA, and these parameters might be helpful for better management of LA thrombosis.


Asunto(s)
Apéndice Atrial , Fibrilación Atrial , COVID-19 , Atrios Cardíacos , Procesamiento de Imagen Asistido por Computador/métodos , Imagenología Tridimensional/métodos , Apéndice Atrial/diagnóstico por imagen , Apéndice Atrial/patología , Apéndice Atrial/fisiopatología , Fibrilación Atrial/complicaciones , Fibrilación Atrial/diagnóstico , Velocidad del Flujo Sanguíneo , COVID-19/epidemiología , COVID-19/prevención & control , Ablación por Catéter/métodos , China/epidemiología , Angiografía por Tomografía Computarizada/métodos , Ecocardiografía/métodos , Femenino , Atrios Cardíacos/diagnóstico por imagen , Atrios Cardíacos/patología , Atrios Cardíacos/fisiopatología , Humanos , Control de Infecciones/métodos , Control de Infecciones/organización & administración , Masculino , Persona de Mediana Edad , Innovación Organizacional , Cuidados Preoperatorios/métodos , Ajuste de Riesgo , SARS-CoV-2 , Tromboembolia/etiología , Tromboembolia/prevención & control
18.
J Chem Phys ; 154(6): 064110, 2021 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-33588557

RESUMEN

A formulation of analytic energy first derivatives for the coupled-cluster singles and doubles augmented with noniterative triples [CCSD(T)] method with spin-orbit coupling included at the orbital level and an implementation for evaluation of first-order properties are reported. The standard density-matrix formulation for analytic CC gradient theory adapted to complex algebra has been used. The orbital-relaxation contributions from frozen core, occupied, virtual, and frozen virtual orbitals to analytic spin-orbit CCSD(T) gradients are fully taken into account and treated efficiently, which is of importance to calculations of heavy elements. Benchmark calculations of first-order properties including dipole moments and electric-field gradients using the corresponding exact two-component property integrals are presented for heavy-element containing molecules to demonstrate the applicability and usefulness of the present analytic scheme.

19.
J Chem Phys ; 155(9): 091101, 2021 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-34496585

RESUMEN

We report a generally applicable computational and experimental approach to determine vibronic branching ratios in linear polyatomic molecules to the 10-5 level, including for nominally symmetry-forbidden transitions. These methods are demonstrated in CaOH and YbOH, showing approximately two orders of magnitude improved sensitivity compared with the previous state of the art. Knowledge of branching ratios at this level is needed for the successful deep laser cooling of a broad range of molecular species.

20.
Angew Chem Int Ed Engl ; 60(8): 4289-4299, 2021 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-33140558

RESUMEN

Materials with multifunctionality or multiresponsiveness, especially polymers derived from green, renewable precursors, have recently attracted significant attention resulting from their technological impact. Nowadays, vegetable-oil-based waterborne polyurethanes (WPUs) are widely used in various fields, while strategies for simultaneous realization of their self-healing, reprocessing, shape memory as well as high mechanical properties are still highly anticipated. We report development of a multifunctional castor-oil-based waterborne polyurethane with high strength using controlled amounts of dithiodiphenylamine. The polymer networks possessed high tensile strength up to 38 MPa as well as excellent self-healing efficiency. Moreover, the WPU film exhibited a maximum recovery of 100 % of the original mechanical properties after reprocessing four times. The broad glass-transition temperature of the samples endowed the films with a versatile shape-memory effect, including a dual-to-quadruple shape-memory effect.

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