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Terahertz (THz) tomographic imaging based on time-resolved THz signals has raised significant attention due to its non-invasive, non-destructive, non-ionizing, material-classification, and ultrafast-frame-rate nature for object exploration and inspection. However, the material and geometric information of the tested objects is inherently embedded in the highly distorted THz time-domain signals, leading to substantial computational complexity and the necessity for intricate multi-physics models to extract the desired information. To address this challenge, we present a THz multi-dimensional tomographic framework and multi-scale spatio-spectral fusion Unet (MS3-Unet), capable of fusing and collaborating the THz signals across diverse signal domains. MS3-Unet employs multi-scale branches to extract spatio-spectral features, which are subsequently processed through element-wise adaptive filters and fused to achieve high-quality THz image restoration. Evaluated by geometry-variant objects, MS3-Unet outperforms other peer methods in PSNR and SSIM. In addition to the superior performance, the proposed framework additionally provides high scalable, adjustable, and accessible interface to collaborate with different user-defined models or methods.
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Data acquisition, image processing, and image quality are the long-lasting issues for terahertz (THz) 3D reconstructed imaging. Existing methods are primarily designed for 2D scenarios, given the challenges associated with obtaining super-resolution (SR) data and the absence of an efficient SR 3D reconstruction framework in conventional computed tomography (CT). Here, we demonstrate BLIss, a new approach for THz SR 3D reconstruction with sparse 2D data input. BLIss seamlessly integrates conventional CT techniques and variational framework with the core of the adapted Euler-Elastica-based model. The quantitative 3D image evaluation metrics, including the standard deviation of Gaussian, mean curvatures, and the multi-scale structural similarity index measure (MS-SSIM), validate the superior smoothness and fidelity achieved with our variational framework approach compared with conventional THz CT modal. Beyond its contributions to advancing THz SR 3D reconstruction, BLIss demonstrates potential applicability in other imaging modalities, such as X-ray and MRI. This suggests extensive impacts on the broader field of imaging applications.
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PR65 is the HEAT repeat scaffold subunit of the heterotrimeric protein phosphatase 2A (PP2A) and an archetypal tandem repeat protein. Its conformational mechanics plays a crucial role in PP2A function by opening/closing substrate binding/catalysis interface. Using in silico saturation mutagenesis, we identified PR65 "hinge" residues whose substitutions could alter its conformational adaptability and thereby PP2A function, and selected six mutations that were verified to be expressed and soluble. Molecular simulations and nanoaperture optical tweezers revealed consistent results on the specific effects of the mutations on the structure and dynamics of PR65. Two mutants observed in simulations to stabilize extended/open conformations exhibited higher corner frequencies and lower translational scattering in experiments, indicating a shift toward extended conformations, whereas another displayed the opposite features, confirmed by both simulations and experiments. The study highlights the power of single-molecule nanoaperture-based tweezers integrated with in silico approaches for exploring the effect of mutations on protein structure and dynamics.
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Simulación de Dinámica Molecular , Pinzas Ópticas , Mutación Puntual , Conformación Proteica , Proteína Fosfatasa 2/genética , Proteína Fosfatasa 2/química , Proteína Fosfatasa 2/metabolismo , HumanosRESUMEN
Background: The value of semiquantitative resting myocardial perfusion imaging (MPI) in coronary artery disease (CAD) is limited. At present, quantitative MPI can be performed by a new cadmium zinc tellurium single-photon emission computed tomography (CZT-SPECT) scan. The quantitative index of resting myocardial blood flow (MBF) has received little attention, and its manifestations and clinical value in the presence of unstable coronary blood flow have not been clarified. Purpose: In patients with ST-segment elevation myocardial infarction (STEMI), whether resting MBF can provide additional value of blood flow than semi-quantitative resting MPI is not sure. We also explored the influencing factors of resting MBF. Methods: This was a retrospective clinical study. We included 75 patients with STEMI in the subacute phase who underwent resting MPI and dynamic scans after reperfusion therapy. General patient information, STEMI-related data, MPI, gated MPI (G-MPI), and resting MBF data were collected and recorded. According to the clinically provided culprit vessels, the resting MBF was divided into ischemic MBF and non-ischemic MBF. The paired Wilcoxon signed-rank test was used for resting MBF. The receiver operating characteristic (ROC) curves were used to determine the optimal threshold for ischemia, and multiple linear regression analysis was used to analyze the influencing factors of resting MBF. Results: There was a statistically significant difference between the ischemic MBF and non-ischemic MBF [0.59 (0.47-0.72) vs. 0.76 (0.64-0.93), p < 0.0001]. The ROC curve analysis revealed that resting MBF could identify ischemia to a certain extent, with a cutoff value of 0.5975, area under the curve (AUC) = 0.666, sensitivity = 55.8%, and specificity = 68.7%. Male sex and summed rest score (SRS) were influencing factors for resting MBF. Conclusion: To a certain extent, resting MBF can suggest residual ischemia after reperfusion therapy in patients with STEMI. There was a negative correlation between male sex, SRS, and ischemic MBF. A lower resting MBF may be associated with more severe myocardial ischemia.
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This study aimed to characterize the sensory profiles of wines produced using the flash détente (FD) technique and to identify the flavor compounds contributing to the sensory characteristics. The FD technique was applied to two major grape varieties, Cabernet Sauvignon and Marselan, from the Changli region of China to produce high-quality wines with aging potential. Compared to the traditional macerated wines, the FD wines showed greater color intensity, mainly due to the higher levels of anthocyanins. Regarding the aroma characteristics, FD wines were found to have a more pronounced fruitness, especially fresh fruit note, which was due to the contribution of higher concentration of esters. Concurrently, FD wines showed an increased sweet note which was associated with increased lactones and furanones. In addition, FD wines exhibited reduced green and floral notes due to lower levels of C6 alcohols and C13-norisoprenoids. With regard to mouthfeel, FD wines presented greater astringency and bitterness, which was due to the higher levels of phenolics. The total concentration of condensed tannins and condensed tannins for each degree of polymerization was considerably higher in FD wines due to the strong extraction of the FD technique. A significant increase in grape-derived polysaccharides and glycerol was also found in FD wines, contributing to a fuller body. This study contributed to an increase in the knowledge of the Changli region and demonstrated that the FD technique could be applied to the wine production in this region to address the negative impacts of rainfall in individual vintages.
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Proantocianidinas , Vino , Antocianinas , AstringentesRESUMEN
Sub-terahertz (Sub-THz) waves possess exceptional attributes, capable of penetrating non-metallic and non-polarized materials while ensuring bio-safety. However, their practicality in imaging is marred by the emergence of troublesome speckle artifacts, primarily due to diffraction effects caused by wavelengths comparable to object dimensions. In addressing this limitation, we present the Diffuser-aided sub-THz Imaging System (DaISy), which utilizes a diffuser and a focusing lens to convert coherent waves into incoherent counterparts. The cornerstone of our progress lies in a coherence theory-based theoretical framework, pivotal for designing and validating the THz diffuser, and systematically evaluating speckle phenomena. Our experimental results utilizing DaISy reveal substantial improvements in imaging quality and nearly diffraction-limited spatial resolution. Moreover, we demonstrate a tangible application of DaISy in the scenario of security scanning, highlighting the versatile potential of sub-THz waves in miscellaneous fields.
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Mitophagy is a process that selectively removes excess or damaged mitochondria and plays an important role in regulating intracellular mitochondrial mass and maintaining mitochondrial energy metabolism. TANK-binding kinase 1 (TBK1) is a multifunctional serine/threonine protein kinase, which is involved in the regulation of PTEN-induced putative kinase 1 (PINK1)/Parkin-dependent and -independent mitophagy. Recent studies have shown that TBK1 phosphorylates the autophagy related proteins, such as optineurin (OPTN), p62/sequestosome-1, Ras-related GTP binding protein 7 (Rab7), and mediates the binding of nuclear dot protein 52 (NDP52) to UNC-51 like autophagy activating kinase 1 (ULK1) complex, as well as the binding of TAX1-binding protein 1 (TAX1BP1) to microtubule-associated protein 1 light chain 3 (LC3), thereby enhancing PINK1/Parkin-dependent mitophagy. In addition, TBK1 is a direct substrate of AMP-activated protein kinase (AMPK)/ULK1 pathway, and its activation phosphorylates dynamin-related protein 1 (Drp1) and Rab7 to promote PINK1/Parkin-independent mitophagy. This article reviews the role and mechanism of TBK1 in regulating PINK1/Parkin-dependent and -independent mitophagy.
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Mitofagia , Ubiquitina-Proteína Ligasas , Proteínas Quinasas Activadas por AMP , Autofagia , Metabolismo EnergéticoRESUMEN
This study explores the impact of bank market structure on firm innovation in China using a two-way fixed effects model. Our analysis is based on a dataset comprising 2,412,316 firm-city level observations. Our findings suggest that there exists a U-shaped relationship between bank market structure and firm innovation in China. Specifically, we identify that the financing channel is a crucial pathway through which bank market structure influences firm innovation. Moreover, our results indicate that this relationship is mainly driven by small firms and innovative firms, and is more pronounced in regions with stronger intellectual property rights protection or greater openness to foreign markets. In sum, this study contributes to the existing literature by advancing our understanding of the impact of bank market structure on innovation in Chinese firms.
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Internacionalidad , ChinaRESUMEN
BACKGROUND: Fat-suppressed (FS) T2-weighed turbo spin-echo (TSE) sequence was used to detect the signal of the thymus and the characteristics of the thymus location, measure the two-dimensional diameter at specific levels, and analyze the association with gestational weeks. METHODS: This study involved 51 fetal specimens. Post-mortem MRI scanning was implemented with a 3.0-T MRI system. T2-weighted imaging (T2WI) features of the thymus in fetuses were quantitatively investigated with DICOM images. Statistical analysis was done with the Chi-Square test, oneway ANOVA, and Student's t-test. RESULTS: There was heterogeneity in the morphology of the fetal thymus. FS T2-weighted TSE sequence clearly exhibited the microstructure of the fetal thymus. The thymus extensively showed a lobulated appearance. The central signal is much higher than the peripheral signal in each lobule. In addition, FS-T2WI images can clearly show the interlobular septum, which is filled with fluid and presents a linear high signal. The signal intensity of fetal thymus increased with gestational weeks. The diameter measured in a particular plane was highly correlated with gestational week. CONCLUSION: FS T2-weighted TSE sequence provides high-resolution images of the fetal thymus. The change in signal intensity, location, and two-dimensional diameter in a specific plane can be used as a research direction for the fetal thymus.
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In biological organisms, metal ion-binding proteins participate in numerous metabolic activities and are closely associated with various diseases. To accurately predict whether a protein binds to metal ions and the type of metal ion-binding protein, this study proposed a classifier named MIBPred. The classifier incorporated advanced Word2Vec technology from the field of natural language processing to extract semantic features of the protein sequence language and combined them with position-specific score matrix (PSSM) features. Furthermore, an ensemble learning model was employed for the metal ion-binding protein classification task. In the model, we independently trained XGBoost, LightGBM, and CatBoost algorithms and integrated the output results through an SVM voting mechanism. This innovative combination has led to a significant breakthrough in the predictive performance of our model. As a result, we achieved accuracies of 95.13% and 85.19%, respectively, in predicting metal ion-binding proteins and their types. Our research not only confirms the effectiveness of Word2Vec technology in extracting semantic information from protein sequences but also highlights the outstanding performance of the MIBPred classifier in the problem of metal ion-binding protein types. This study provides a reliable tool and method for the in-depth exploration of the structure and function of metal ion-binding proteins.
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Porous materials with d3 electronic configuration open metal sites have been proved to be effective adsorbents for N2 capture and N2 /O2 separation. However, the reported materials remain challenging to address the trade-off between adsorption capacity and selectivity. Herein, we report a robust MOF, MIL-102Cr, that features two binding sites, can synergistically afford strong interactions for N2 capture. The synergistic adsorption site exhibits a benchmark Qst of 45.0â kJ mol-1 for N2 among the Cr-based MOFs, a record-high volumetric N2 uptake (31.38â cm3 cm-3 ), and highest N2 /O2 selectivity (13.11) at 298â K and 1.0â bar. Breakthrough experiments reveal that MIL-102Cr can efficiently capture N2 from a 79/21â N2 /O2 mixture, providing a record 99.99 % pure O2 productivity of 0.75â mmol g-1 . In situ infrared spectroscopy and computational modelling studies revealed that a synergistic adsorption effect by open Cr(III) and fluorine sites was accountable for the strong interactions between the MOF and N2 .
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PR65 is the HEAT-repeat scaffold subunit of the heterotrimeric protein phosphatase 2A (PP2A) and an archetypal tandem-repeat protein, forming a spring-like architecture. PR65 conformational mechanics play a crucial role in PP2A function by opening/closing the substrate-binding/catalysis interface. Using in-silico saturation mutagenesis we identified "hinge" residues of PR65, whose substitutions are predicted to restrict its conformational adaptability and thereby disrupt PP2A function. Molecular simulations revealed that a subset of hinge mutations stabilized the extended/open conformation, whereas another had the opposite effect. By trapping in nanoaperture optical tweezer, we characterized PR65 motion and showed that the former mutants exhibited higher corner frequencies and lower translational scattering, indicating a shift towards extended conformations, whereas the latter showed the opposite behavior. Thus, experiments confirm the conformations predicted computationally. The study highlights the utility of nanoaperture-based tweezers for exploring structure and dynamics, and the power of integrating this single-molecule method with in silico approaches.
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Purpose: To analyze the independent associations of miRNA-146a and miRNA-223 with rheumatoid arthritis (RA) and evaluate their predictive values for RA. Patients and Methods: A total of 68 RA patients were selected as cases, and meanwhile 68 patients with a traumatic knee condition were selected as controls by matching to the cases according to sex and age at the ratio of 1:1. The independent associations of miRNA-146a and miRNA-223 with RA were identified by binary logistic regression analysis. Receiver operating characteristic (ROC) curve was used to evaluate their predictive values for RA. Results: MiRNA-146a and miRNA-223 expression levels in both synovial tissues and serums were statistically higher in cases than in controls, and their expression levels in serums were not statistically different from those in synovial tissues in both cases and controls. The expression levels of miRNA-146a and miRNA-223 in synovial tissues were independently associated with RA, as well as the expression levels of miRNA-146a and miRNA-223 in serums. The area under curve (AUC) of combination of miRNA-146a and miRNA-223 in synovial tissues for the prediction of RA was 0.910 [95% confidence interval (CI): 0.863-0.962], and the AUC of combination of miRNA-146a and miRNA-223 in serums was 0.904 (95% CI: 0.851-0.957). Their difference was not statistically significant (P=0.873), but the AUC of combination prediction was statistically higher than those of individual predictions (synovial tissues: 0.910 vs 0.773, P=0.005, 0.910 vs 0.788, P=0.009; serums: 0.904 vs 0.766, P=0.005, 0.904 vs 0.784, P=0.011). Conclusion: MiRNA-146a and miRNA-223 in both synovial tissues and serums could be applied in predicting RA, and their combination could elevate the predictive value significantly.
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Terahertz (THz) tomographic imaging has recently attracted significant attention thanks to its non-invasive, non-destructive, non-ionizing, material-classification, and ultra-fast nature for object exploration and inspection. However, its strong water absorption nature and low noise tolerance lead to undesired blurs and distortions of reconstructed THz images. The diffraction-limited THz signals highly constrain the performances of existing restoration methods. To address the problem, we propose a novel multi-view Subspace-Attention-guided Restoration Network (SARNet) that fuses multi-view and multi-spectral features of THz images for effective image restoration and 3D tomographic reconstruction. To this end, SARNet uses multi-scale branches to extract intra-view spatio-spectral amplitude and phase features and fuse them via shared subspace projection and self-attention guidance. We then perform inter-view fusion to further improve the restoration of individual views by leveraging the redundancies between neighboring views. Here, we experimentally construct a THz time-domain spectroscopy (THz-TDS) system covering a broad frequency range from 0.1 to 4 THz for building up a temporal/spectral/spatial/material THz database of hidden 3D objects. Complementary to a quantitative evaluation, we demonstrate the effectiveness of our SARNet model on 3D THz tomographic reconstruction applications. Supplementary Information: The online version contains supplementary material available at 10.1007/s11263-023-01812-y.
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Numerous studies have found that repetitive transcranial magnetic stimulation (rTMS) modulates plasticity. rTMS has often been used to change neural networks underlying learning, often under the assumption that the mechanism of rTMS-induced plasticity should be highly similar to that associated with learning. The presence of visual perceptual learning (VPL) reveals the plasticity of early visual systems, which is formed through multiple phases. Hence, we tested how high-frequency (HF) rTMS and VPL modulate the effect of visual plasticity by investigating neurometabolic changes in early visual areas. We employed an excitatory-to-inhibitory (E/I) ratio, which refers to glutamate concentration divided by GABA+ concentration, as an index of the degree of plasticity. We compared neurotransmitter concentration changes after applying HF rTMS to the visual cortex with those after training in a visual task, in otherwise identical procedures. Both the time courses of the E/I ratios and neurotransmitter contributions to the E/I ratio significantly differed between HF rTMS and training conditions. The peak E/I ratio occurred 3.5 h after HF rTMS with decreased GABA+, whereas the peak E/I ratio occurred 0.5 h after visual training with increased glutamate. Furthermore, HF rTMS temporally decreased the thresholds for detecting phosphene and perceiving low-contrast stimuli, indicating increased visual plasticity. These results suggest that plasticity in early visual areas induced by HF rTMS is not as involved in the early phase of development of VPL that occurs during and immediately after training.
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Aprendizaje Espacial , Estimulación Magnética Transcraneal , Estimulación Magnética Transcraneal/métodos , Redes Neurales de la Computación , Ácido gamma-AminobutíricoRESUMEN
BACKGROUND: With improved resolution and sensitivity, the cadmium zinc telluride (CZT) detector measures myocardial blood flow (MBF) and myocardial flow reserve (MFR) via single photon emission computed tomography (SPECT). Recently, many studies have used vasodilator stress to obtain quantitative indexes. However, dobutamine used as a pharmaceutical stress has been rarely used to quantify myocardial perfusion using CZT-SPECT. Our study retrospectively analyzed the blood flow performance of 99mTc-Sestamibi (99mTc -MIBI) CZT-SPECT comparing dobutamine to adenosine. PURPOSE: The study aims to explore whether dobutamine stress can be used for the myocardial perfusion quantitative analysis via CZT-SPECT as well as compare dobutamine MBF and MFR to adenosine. METHODS: It was a retrospective study. A total of 68 patients with suspected or known coronary artery disease (CAD) were consecutively enrolled in this study. Thirty-four patients underwent dobutamine stress 99mTc-MIBI CZT-SPECT. Another thirty-four patients underwent adenosine stress 99mTc-MIBI CZT-SPECT. Patient characteristics, myocardial perfusion imaging (MPI) results, gated-myocardial perfusion imaging (G-MPI) results and quantitative analysis of MBF and MFR were collected. RESULTS: In dobutamine stress group, stress MBF was significantly higher than rest MBF (median [interquartile range], 1.63 [1.46-1.94] vs. 0.89 [0.73-1.06], P < 0.001). In adenosine stress group, similar results were observed (median [interquartile range], 2.01 [1.34-2.20] vs. 0.88 [0.75-1.01], P < 0.001). When comparing the dobutamine and adenosine stress group, global MFR showed significant differences (median [interquartile range], the dobutamine group: 1.88 [1.67-2.38] vs. the adenosine group: 2.19 [1.87-2.64], P = 0.037). CONCLUSION: MBF and MFR can be measured using dobutamine 99mTc -MIBI CZT-SPECT. In small sample single-center study, there was a difference in MFR produced by adenosine and dobutamine within the suspected or the known CAD population.
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Enfermedad de la Arteria Coronaria , Imagen de Perfusión Miocárdica , Humanos , Dobutamina , Estudios Retrospectivos , Cadmio , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Tomografía Computarizada de Emisión de Fotón Único/métodos , Tecnecio Tc 99m Sestamibi , Adenosina , Zinc , Imagen de Perfusión Miocárdica/métodosRESUMEN
PR65, a horseshoe-shaped scaffold composed of 15 HEAT (observed in Huntingtin, elongation factor 3, protein phosphatase 2A, and the yeast kinase TOR1) repeats, forms, together with catalytic and regulatory subunits, the heterotrimeric protein phosphatase PP2A. We examined the role of PR65 in enabling PP2A enzymatic activity with computations at various levels of complexity, including hybrid approaches that combine full-atomic and elastic network models. Our study points to the high flexibility of this scaffold allowing for end-to-end distance fluctuations of 40-50 Å between compact and extended conformations. Notably, the intrinsic dynamics of PR65 facilitates complexation with the catalytic subunit and is retained in the PP2A complex enabling PR65 to engage the two domains of the catalytic subunit and provide the mechanical framework for enzymatic activity, with support from the regulatory subunit. In particular, the intra-repeat coils at the C-terminal arm play an important role in allosterically mediating the collective dynamics of PP2A, pointing to target sites for modulating PR65 function.
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Proteína Fosfatasa 2 , Proteína Fosfatasa 2/genética , Regulación Alostérica , Unión Proteica , Dominio CatalíticoRESUMEN
COVID-19 pandemic caused a significant increase in medical and infected domestic waste, greatly increasing risk of human infected with SARS-CoV-2. Therefore, it is critical to prevent the spread of SARS-CoV-2 from solid waste to humans. Current commercial disinfectants present a high carbon footprint issue. Hence, we prepared a renewable wheat straw-based bio-liquid that can damage SARS-CoV-2 RNA and protein. The wet thermochemical extraction (WTE) bio-liquid, with total organic carbon concentration exceeding 1892 mg/L, could effectively damage the virus. However, dry thermochemical extraction (DTE) samples were not efficient due to their low content of effective compounds. The life cycle assessment showed that WTE bio-liquid production implies lower energy and environmental negative impacts than DTE. Moreover, the process by-product, char, can simultaneously reduce 3.1 million tonnes of global CO2 emissions while used as coal substitute. Yield of bio-liquid extremely exceed commercial disinfectant with just 1 % wheat straw utilisation, which meet the demand of processing solid waste. Further, their costs are significantly lower than commercial disinfectants, which are suitable for developing countries. Therefore, the antiviral bio-liquid produced from agricultural straw can be a new way to meet the needs of preventing the spread of SARS-CoV-2 and resume the sustainable development of society.
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COVID-19 , Desinfectantes , Humanos , Animales , Residuos Sólidos , SARS-CoV-2 , Biomasa , Pandemias/prevención & control , ARN Viral , COVID-19/prevención & control , Huella de Carbono , Estadios del Ciclo de VidaRESUMEN
BACKGROUND: It remains a challenge to judge whether comatose patients with acute intracerebral hemorrhage (ICH) can wake up. Here, we aimed to investigate the changes in right ventricle-pulmonary artery (RV-PA) coupling over time in these patients and to evaluate its performance for discriminating between those who woke up within 60 days and those who did not. METHODS: Thirty-five comatose patients with acute spontaneous ICH underwent bedside echocardiography on days 1, 3, and 5 after onset with the measurement of tricuspid annular plane systolic excursion and mean pulmonary artery pressure. The RV-PA coupling (the ratio of tricuspid annular plane systolic excursion to mean pulmonary artery pressure) was calculated. RESULTS: Within 60 days of the onset of coma, 11 individuals awakened and survived, and 24 individuals died. In awakened patients, RV-PA couplings did not differ among days 1, 3, and 5 (1.62 ± 0.38 vs. 1.61 ± 0.32 vs. 1.64 ± 0.25 mm/mm Hg, P > 0.05), whereas in unawakened patients, they decreased drastically from day 1 to day 3 and then to day 5 (1.26 ± 0.32 vs. 0.63 ± 0.05 vs. 0.43 ± 0.06 mm/mm Hg, P < 0.05). The area under receiver operating characteristic curve of 0.992 for the ratio of RV-PA coupling on day 5 to day 1 of the coma was superior to that for the Glasgow Coma Scale (area under receiver operating characteristic curve of 0.606) in the discrimination of comatose patients with ICH who woke up within 60 days from those who did not. The optimal cutoff value was 0.536, with a sensitivity of 100.00%, a specificity of 96.24%, and an accuracy of 97.13%. CONCLUSIONS: Right ventricle-pulmonary artery coupling demonstrated a high performance for discriminating comatose patients with ICH who woke up within 60 days from those who did not.