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1.
BMC Med Educ ; 24(1): 448, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38658906

RESUMO

OBJECTIVES: This study aimed to investigate the utility of the RAND/UCLA appropriateness method (RAM) in validating expert consensus-based multiple-choice questions (MCQs) on electrocardiogram (ECG). METHODS: According to the RAM user's manual, nine panelists comprising various experts who routinely handle ECGs were asked to reach a consensus in three phases: a preparatory phase (round 0), an online test phase (round 1), and a face-to-face expert panel meeting (round 2). In round 0, the objectives and future timeline of the study were elucidated to the nine expert panelists with a summary of relevant literature. In round 1, 100 ECG questions prepared by two skilled cardiologists were answered, and the success rate was calculated by dividing the number of correct answers by 9. Furthermore, the questions were stratified into "Appropriate," "Discussion," or "Inappropriate" according to the median score and interquartile range (IQR) of appropriateness rating by nine panelists. In round 2, the validity of the 100 ECG questions was discussed in an expert panel meeting according to the results of round 1 and finally reassessed as "Appropriate," "Candidate," "Revision," and "Defer." RESULTS: In round 1 results, the average success rate of the nine experts was 0.89. Using the median score and IQR, 54 questions were classified as " Discussion." In the expert panel meeting in round 2, 23% of the original 100 questions was ultimately deemed inappropriate, although they had been prepared by two skilled cardiologists. Most of the 46 questions categorized as "Appropriate" using the median score and IQR in round 1 were considered "Appropriate" even after round 2 (44/46, 95.7%). CONCLUSIONS: The use of the median score and IQR allowed for a more objective determination of question validity. The RAM may help select appropriate questions, contributing to the preparation of higher-quality tests.


Assuntos
Eletrocardiografia , Humanos , Consenso , Reprodutibilidade dos Testes , Competência Clínica/normas , Avaliação Educacional/métodos , Cardiologia/normas
2.
Heart Vessels ; 39(5): 454-463, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38321356

RESUMO

Cardioembolic stroke is a serious disease with poor prognosis, whose main embolic source is the left atrial appendage (LAA). Left atrial (LA) strain evaluated by the two-dimensional (2D) speckle tracking technique has been proposed. However, the commonly used peak LA strain reflects only LA reservoir function. The LA strain also includes indicators of the other LA functions, such as booster pump function, which reflects active contraction of the LA. This study aimed to investigate whether a newly developed parameter, the left atrial strain time integral (LASTI), can evaluate LAA dysfunction more accurately in patients with acute stroke. We measured LA strain using a 2D speckle tracking method in 168 patients with acute stroke and 20 age-matched control subjects. LASTI was calculated as the area under the LA strain curve in one cardiac cycle. LAA dysfunction was defined as LAA thrombus and/or severe spontaneous echo contrast by transesophageal echocardiography. LASTI was significantly lower in patients with LAA dysfunction than those without. LASTI was a better correlation with LAA blood flow velocity measured by transesophageal echocardiography than peak LA strain. Multivariate logistic regression analysis showed that LASTI was an independent predictor of LAA dysfunction after adjustment for conventional risk factors. LASTI can be a feasible parameter for predicting LAA dysfunction in patients with acute stroke.


Assuntos
Apêndice Atrial , Fibrilação Atrial , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Apêndice Atrial/diagnóstico por imagem , AVC Isquêmico/complicações , Fibrilação Atrial/complicações , Fibrilação Atrial/diagnóstico , Átrios do Coração , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/etiologia , Ecocardiografia Transesofagiana/métodos
3.
Phys Rev Lett ; 131(23): 236702, 2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38134797

RESUMO

Certain types of media breaking both space-inversion (P) and time-reversal (T) symmetries but preserving their combination PT exhibit the polarization rotation of reflected light even when that of transmitted light is prohibited. Such an effect is termed nonreciprocal rotation of reflected light (NRR). Although NRR shows nearly the same phenomenon as the magnetooptical Kerr effect or, equivalently, the Hall effect at optical frequencies, its origin is distinct and ascribed to a magnetoelectric (ME) effect at optical frequencies, i.e., the optical ME effect. Here we show the observation of NRR in a metallic antiferromagnet TbB_{4}. The result demonstrates that the ME effect in a metallic system, which is considered to be ill defined, can be detected using reflected light. Furthermore, we spatially resolve antiferromagnetic domains in TbB_{4} by microscope observations of NRR. Our work offers a unique way to probe the ME effect in metallic systems.

4.
J Clin Med ; 12(19)2023 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-37834976

RESUMO

In the present prospective case series study, we investigated the lesion-detection ability of an AI-equipped colonoscopy as an addition to colonoscopy (CS) screening. Participants were 100 patients aged ≥20 years who had not undergone CS at the study site in the last 3 years and passed the exclusion criteria. CS procedures were conducted using conventional white light imaging and computer-aided detection (CADe). Adenoma detection rate (ADR; number of individuals with at least one adenoma detected) was compared between the conventional group and the CADe group. Of the 170 lesions identified, the ADR of the CADe group was significantly higher than the ADR of the conventional group (69% vs. 61%, p = 0.008). For the expert endoscopists, although ADR did not differ significantly, the mean number of detected adenomas per procedure (MAP) was significantly higher in the CADe group than in the conventional group (1.7 vs. 1.45, p = 0.034). For non-expert endoscopists, ADR and MAP were significantly higher in the CADe group than in the conventional group (ADR 69.5% vs. 56.6%, p = 0.016; MAP 1.66 vs. 1.11, p < 0.001). These results indicate that the CADe function in CS screening has a positive effect on adenoma detection, especially for non-experts.

5.
J Cardiol Cases ; 28(4): 150-152, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37818434

RESUMO

A 68-year-old woman with idiopathic dilated cardiomyopathy presented with a wide QRS complex regular tachycardia five days after mitral valve replacement. Adenosine triphosphate (ATP) was administered to make the correct diagnosis; however, tachycardia eventually transitioned to ventricular fibrillation, which required cardioversion. Although ATP is considered a relatively safe drug, it can cause unexpected, life-threatening arrhythmias. Careful monitoring and preparation are advised during ATP administration in the event of a regular wide QRS complex tachycardia in patients with irritable conditions. Learning objective: Adenosine triphosphate (ATP) is considered a safe drug that is often used to manage wide QRS complex tachycardia. Herein, we present a case of regular, wide QRS complex tachycardia in a patient who underwent mitral valve replacement. Tachycardia degenerated into ventricular fibrillation soon after ATP administration, probably because of sympathetic overdrive secondary to the ATP infusion. It is advisable to use ATP with caution, especially in irritable cases such as in the early post-cardiac surgery period.

6.
J Cardiol Cases ; 28(4): 168-171, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37818436

RESUMO

A 74-year-old man who had undergone surgical aortic valve replacement with the SOLO SMART stentless bioprosthetic valve 25 mm (LivaNova PLC, London, UK) and mitral valve replacement with MOSAIC 29 mm (Medtronic, Minneapolis, USA) 4 years previously was diagnosed with congestive heart failure, and transferred to our hospital. Echocardiography revealed severe aortic regurgitation caused by degraded bioprosthetic valve. He required continuous dobutamine administration to maintain hemodynamics. As a result of heart team discussion, we decided to perform transcatheter valve-in-valve implantation (ViV-TAVI) using balloon expandable valve (Sapien 3, Edwards Lifesciences, Irvine, USA). Since SOLO SMART stentless valve was placed to Valsalva sinus at the supra-annular level with continuous sutures, we planned to anchor TAVI valve 4 mm to the left ventricular side from the bottom of the failed stentless valve. Two pigtail catheters were placed at the bottom of the failed stentless valve leaflet to mark the nadir of stentless valve. After ViV-TAVI, the patient no longer required catecholamine administration and was discharged home one month later. This is the first case of ViV-TAVI using balloon expandable valve for failed SOLO SMART stentless bioprosthetic valve in a Japanese patient. Learning objective: Transcatheter valve-in-valve implantation (ViV-TAVI) for stentless valves is known to be technically challenging due to poor fluoroscopic visibility. Because the SOLO SMART stentless bioprosthetic valve is sutured to the wall of the sinus of Valsalva above the annulus, the landing point of transcatheter heart valve is at a native annulus which is lower than the bottom of the SOLO SMART leaflet. We describe the first Japanese case of ViV-TAVI with balloon expandable valve for the SOLO SMART stentless bioprosthetic valve.

8.
J Cardiol ; 82(5): 388-397, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37343930

RESUMO

BACKGROUND: Although remote monitoring (RM) after pacemaker implantation is common, its cost-effectiveness has not been fully investigated. Therefore, we assessed the cost-effectiveness of RM compared with conventional follow-up (CFU) in Japanese patients with pacemakers. METHODS: A Markov model was constructed to analyze costs and quality-adjusted life years after pacemaker implantation. The target population was Japanese patients implanted with a dual-chamber pacemaker for bradycardia. Transition probabilities (e.g. atrial fibrillation, stroke, and device trouble) were obtained from literature and expert sources. Additionally, stroke risk was determined according to anticoagulation and CHADS2 scores. We used a 10-year horizon with sensitivity analyses for significant variables. RESULTS: Compared to CFU, RM was more effective; however, it was also more expensive. When the range of the Japanese willingness-to-pay threshold was considered to be ¥5,000,000, RM was at least cost-neutral relative to the CFU in all elderly patients with pacemakers for bradycardia. The cost-effectiveness of RM relative to CFU could be higher for patients with high CHADS2 scores, especially in patients with a CHADS2 score ≥ 3. Scenario analyses changing the interval between visits to an in-office evaluation in the CFU also demonstrated the same conclusions. In particular, when the interval between office visits was 1 year for the CFU, the RM could be more cost-effective. CONCLUSIONS: This study demonstrated that RM can be a cost-effective option for Japanese patients, especially those with high CHADS2 scores and long-term intervals between office visits.


Assuntos
Fibrilação Atrial , Marca-Passo Artificial , Acidente Vascular Cerebral , Humanos , Idoso , Bradicardia/etiologia , Bradicardia/terapia , Análise de Custo-Efetividade , Japão , Análise Custo-Benefício , Fibrilação Atrial/epidemiologia
9.
J Ethnopharmacol ; 314: 116605, 2023 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-37178982

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Bu-Zhong-Yi-Qi-Tang is a famous traditional Chinese medicine formula that has been prevalent in China for over 700 years to treat spleen-qi deficiency related diseases, such as gastrointestinal and respiratory disorders. However, the bioactive components responsible for regulating spleen-qi deficiency remain unclear and have puzzled many researchers. AIM OF THE STUDY: The current study focuses on efficacy evaluation of regulating spleen-qi deficiency and screening the bioactive components of Bu-Zhong-Yi-Qi-Tang. MATERIALS AND METHODS: The effects of Bu-Zhong-Yi-Qi-Tang were evaluated through blood routine examination, immune organ index, and biochemical analysis. Metabolomics was utilized to analyze the potential endogenous biomarkers (endobiotics) in the plasma, and the prototypes (xenobiotics) of Bu-Zhong-Yi-Qi-Tang in the bio-samples were characterized using ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry. Then, these endobiotics were used as "bait" to predict targets based on network pharmacology and to screen potential bioactive components from the absorbed prototypes in the plasma by constructing an "endobiotics-targets-xenobiotics" association network. Further, the anti-inflammatory activities of representative compounds (calycosin and nobiletin) were validated through poly(I:C)-induced pulmonary inflammation mice model. RESULTS: Bu-Zhong-Yi-Qi-Tang exhibited immunomodulatory and anti-inflammatory activities in spleen-qi deficiency rat, as supported by the observation of increased levels of D-xylose and gastrin in serum, an increase in the thymus index and number of lymphocytes in blood, as well as a reduction in the level of IL-6 in bronchoalveolar lavage fluid. Furthermore, plasma metabolomic analysis revealed a total of 36 Bu-Zhong-Yi-Qi-Tang related endobiotics, which were mainly enriched in primary bile acids biosynthesis, the metabolism of linoleic acid, and the metabolism of phenylalanine pathways. Meanwhile, 95 xenobiotics were characterized in plasma, urine, small intestinal contents, and tissues of spleen-qi deficiency rat after Bu-Zhong-Yi-Qi-Tang treatment. Using an integrated association network, six potential bioactive components of Bu-Zhong-Yi-Qi-Tang were screened. Among them, calycosin was found to significantly reduce the levels of IL-6 and TNF-α in the bronchoalveolar lavage fluid, increase the number of lymphocytes, while nobiletin dramatically decreased the levels of CXCL10, TNF-α, GM-CSF, and IL-6. CONCLUSION: Our study proposed an available strategy for screening bioactive components of BYZQT regulating spleen-qi deficiency based on "endobiotics-targets-xenobiotics" association network.


Assuntos
Medicamentos de Ervas Chinesas , Baço , Camundongos , Ratos , Animais , Fator de Necrose Tumoral alfa/farmacologia , Interleucina-6 , Xenobióticos/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Medicamentos de Ervas Chinesas/química , Anti-Inflamatórios/farmacologia
11.
J Am Chem Soc ; 145(14): 8090-8098, 2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-36988395

RESUMO

Ferroaxial order, characterized by a rotational arrangement of electric dipoles, attracts increasing attention in terms of a new family of ferroic orders. However, there has been no chemical guideline for exploring crystalline materials showing ferroaxial order, namely ferroaxial materials. Here, we present a chemical guideline grounded in staggered polyhedral connectivity, which we propose as a structural prerequisite for ferroaxial order, and the second-order Jahn-Teller (SOJT) theory extended from molecular orbitals to electronic band structures. Na-superionic conductors (NASICON) including NaM2(PO4)3 (M = early-transition or post-transition metal) are identified as potential ferroaxial materials because of their staggered structures composed of MO6 octahedra and PO4 tetrahedra. However, ferroaxial phase transitions hardly occur in some of the NASICON systems, which offers a platform to uncover a hidden factor playing an important role in driving this system into ferroaxial states. Our first-principles calculations demonstrate that a ferroaxial phase transition in NASICON systems occurs only when SOJT interaction is symmetrically allowed, that is, energy-lowering chemical bonds are formed as a consequence of the distortion. Our proposals would be not limited to NASICON systems but applicable to a variety of compounds and provide new insight into the exploration of displacive-type ferroaxial materials.

12.
Eur Heart J Digit Health ; 4(2): 119-124, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36974263

RESUMO

Aims: Currently, virtual reality (VR) constitutes a vital aspect of digital health, necessitating an overview of study trends. We classified type A studies as those in which health care providers utilized VR devices and type B studies as those in which patients employed the devices. This study aimed to analyse the characteristics of each type of studies using natural language processing (NLP) methods. Methods and results: Literature related to VR in cardiovascular research was searched in PubMed between 2010 and 2022. The characteristics of studies were analysed based on their classification as type A or type B. Abstracts of the studies were used as corpus for text mining. A binary logistic regression model was trained to automatically categorize the abstracts into the two study types. Classification performance was evaluated by accuracy, precision, recall, F-1 score, and c-statistics of the receiver operator curve (ROC) analysis. In total, 171 articles met the inclusion criteria, where 120 (70.2%) were type A studies and 51 (29.8%) were type B studies. Type A studies had a higher proportion of case reports than type B studies (18.3% vs. 3.9%, P = 0.01). As for abstract classification, the binary logistic regression model yielded 88% accuracy and an area under the ROC of 0.98. The words 'training', '3d', and 'simulation' were the most powerful determinants of type A studies, while the words 'patients', 'anxiety', and 'rehabilitation' were more indicative for type B studies. Conclusions: NLP methods revealed the characteristics of the two types of VR-related research in cardiology.

13.
Lab Invest ; 103(6): 100105, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36842278

RESUMO

Patient-derived tumor organoids have considerable potential as an in vitro diagnostic tool for drug susceptibility testing. In the present study, we investigated whether bile collected for diagnostic purposes could be a potential source for the establishment of biliary cancer organoids. Among 68 cases of biliary cancer, we successfully generated 60 bile-derived organoids (BDOs) from individual patients. Consistent with previous reports that described biliary cancer organoids from surgical tissues, the BDOs showed diverse morphologies such as simple cysts, multiloculated cysts, thick capsulated cysts, and solid masses. They also harbored mutations in KRAS and TP53 at frequencies of 15% and 55%, respectively. To enrich the cancer organoids by removing contaminated noncancerous components of BDOs, we attempted to verify the effectiveness of 3 different procedures, including repeat passage, xenografting, and selection with an MDM2 inhibitor for TP53 mutation-harboring BDOs. By monitoring the sequence and expression of mutated TP53, we found that all these procedures successfully enriched the cancer organoids. Our data suggest that BDOs can be established with minimal invasiveness from almost all patients with biliary cancers, including inoperable cases. Thus, despite some limitations with respect to the characterization of BDOs and methods for the enrichment of cancer cell-derived organoids, our data suggest that BDOs could have potential applications in personalized medicine.


Assuntos
Cistos , Mycobacterium tuberculosis , Humanos , Bile/metabolismo , Testes de Sensibilidade Microbiana , Organoides/patologia , Cistos/metabolismo , Cistos/patologia
14.
Jpn J Radiol ; 41(8): 843-853, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36811719

RESUMO

PURPOSE: To evaluate left atrial (LA) function in patients with hypertrophic cardiomyopathy (HCM) by LA strain assessment using cardiac computed tomography (CT-derived LA strain). MATERIALS AND METHODS: This was a retrospective study of 34 patients with HCM and 31 non-HCM patients who underwent cardiac computed tomography (CT) using retrospective electrocardiogram-gated mode. CT images were reconstructed every 5% (0-95%) of the RR intervals. CT-derived LA strain (reservoir [LASr], conduit [LASc], and booster pump strain [LASp]) were semi-automatically analyzed using a dedicated workstation. We also measured the left atrial volume index (LAVI) and left ventricular longitudinal strain (LVLS) for the left atrial and ventricular functional parameters to assess the relationship with CT-derived LA strain. RESULTS: CT-derived LA strain significantly correlated with LAVI: r = - 0.69, p < 0.001 for LASr; r = - 0.70, p < 0.001 for LASp; and r = - 0.35, p = 0.004 for LASc. CT-derived LA strain also significantly correlated with LVLS: r = - 0.62, p < 0.001 for LASr; r = - 0.67, p < 0.001 for LASc; and r = - 0.42, p = 0.013 for LASp. CT-derived LA strain in patients with HCM was significantly lower than that in non-HCM patients: LASr (20.8 ± 7.6 vs. 31.7 ± 6.1%, p < 0.001); LASc (7.9 ± 3.4 vs. 14.2 ± 5.3%, p < 0.001); and LASp (12.8 ± 5.7 vs. 17.6 ± 4.3%, p < 0.001). Additionally, CT-derived LA strain showed high reproducibility; inter-observer correlation coefficients were 0.94, 0.90, and 0.89 for LASr, LASc, and LASp, respectively. CONCLUSION: CT-derived LA strain is feasible for quantitative assessment of left atrial function in patients with HCM.


Assuntos
Fibrilação Atrial , Cardiomiopatia Hipertrófica , Humanos , Estudos Retrospectivos , Reprodutibilidade dos Testes , Átrios do Coração/diagnóstico por imagem , Cardiomiopatia Hipertrófica/diagnóstico por imagem , Tomografia
15.
Pacing Clin Electrophysiol ; 46(2): 152-160, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36524673

RESUMO

BACKGROUND: Although premature atrial contractions (PACs) just after catheter ablation (CA) for atrial fibrillation (AF) are common, their clinical significance is uncertain. This study aimed to evaluate whether the PAC burden after an initial CA for AF was associated with late recurrence. METHODS: We enrolled 346 patients with AF (median age, 65 years; 30% female; 57% with paroxysmal AF) who underwent an initial radiofrequency CA and a 24-h Holter monitoring the day after the procedure. PAC was defined as supraventricular complexes occurring ≥30% earlier than expected compared with a previous RR interval, and the number of PAC/24 h during post-procedural Holter monitoring was analyzed. RESULTS: AF recurred in 106 patients (31%) during a median follow-up of 19 months. These patients had significantly more PAC/24 h than those without (median [interquartile range], 891 [316-4351] beats vs. 409 [162-1,303] beats; p < 0.01). The number of PACs was independently associated with AF recurrence after adjustment for clinical parameters and left atrial (LA) enlargement. Receiver operating characteristic (ROC) curve analysis revealed that 1431 PAC/24 h was the optimal cut-off value for predicting AF recurrence. Adding the PAC/24 h to the prediction model with LA diameter appeared to correctly reclassify patients who were thought to be at high risk for AF recurrence into the low-risk group and vice versa. CONCLUSIONS: The number of PACs was an independent risk factor for AF recurrence. A 24-h Holter recording the day after an initial CA is a simple and beneficial tool for the risk stratification of AF recurrence.


Assuntos
Fibrilação Atrial , Complexos Atriais Prematuros , Ablação por Cateter , Humanos , Feminino , Idoso , Masculino , Resultado do Tratamento , Fatores de Risco , Ablação por Cateter/efeitos adversos , Recidiva
16.
Front Pharmacol ; 13: 1015486, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36304166

RESUMO

Pulmonary inflammation caused by respiratory tract viral infections is usually associated with acute exacerbation of respiratory diseases, such as asthma and chronic obstructive pulmonary disease (COPD). Therefore, maintaining the pulmonary immune homeostasis is particular important for prevention of the acute exacerbation. Bu-Zhong-Yi-Qi-Tang (BZYQT), a traditional Chinese medicine formula, has been broadly used to improve respiratory and gastrointestinal disorders in China for over 700 years. Previously, we have found the regulatory activity of BZYQT on the lower respiratory immune system, while its potential effects during pulmonary inflammation remain unknown. Thus, the current study focused on deciphering its immunomodulatory effect and potential mechanism against pulmonary inflammation by using a viral RNA analogue, poly (I:C), induced murine pulmonary inflammation model and BEAS-2B cell model coupled with network pharmacology. Inflammatory cells in the bronchoalveolar lavage fluid were counted through microscope examination according to the cell's morphology and staining characteristics; protein and gene levels of inflammatory mediators were determined with Elisa and quantitative PCR, respectively; network pharmacology was conducted based on 46 BZYQT-related potential bioactive components, pulmonary inflammation and immune-related targets. Our results indicated that the recruitment of neutrophils and the expression of Adgre1 (encoding the F4/80, which is a macrophage marker) in the lung induced by poly (I:C) were significantly reduced after BZYQT treatment, and these effects were further demonstrated to be related to the interference of leukocyte transendothelial migration from the decreased levels of CXCL10, IL-6, TNF-α, CXCL2, ICAM-1, VCAM-1, and E/P-selectins. Furthermore, BZYQT inhibited the CXCL10, TNF-α, and IFN-ß expression of poly (I:C)-challenged BEAS-2B cells in a dose-dependent manner. Through integrating results from network pharmacology, experiments, and the published literature, isoliquiritigenin, Z-ligustilide, atractylenolide I, atractylenolide III, formononetin, ferulic acid, hesperidin, and cimigenoside were presumed as the bioactive components of BZYQT against pulmonary inflammation. Overall, our findings demonstrated that BZYQT possesses a pronounced immunomodulatory effect on poly (I:C)-induced pulmonary inflammation, which provides a pharmacological basis for BZYQT in the treatment of respiratory disorders.

17.
Front Robot AI ; 9: 903450, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36246490

RESUMO

In this study, HcVGH, a method that learns spatio-temporal categories by segmenting first-person-view (FPV) videos captured by mobile robots, is proposed. Humans perceive continuous high-dimensional information by dividing and categorizing it into significant segments. This unsupervised segmentation capability is considered important for mobile robots to learn spatial knowledge. The proposed HcVGH combines a convolutional variational autoencoder (cVAE) with HVGH, a past method, which follows the hierarchical Dirichlet process-variational autoencoder-Gaussian process-hidden semi-Markov model comprising deep generative and statistical models. In the experiment, FPV videos of an agent were used in a simulated maze environment. FPV videos contain spatial information, and spatial knowledge can be learned by segmenting them. Using the FPV-video dataset, the segmentation performance of the proposed model was compared with previous models: HVGH and hierarchical recurrent state space model. The average segmentation F-measure achieved by HcVGH was 0.77; therefore, HcVGH outperformed the baseline methods. Furthermore, the experimental results showed that the parameters that represent the movability of the maze environment can be learned.

18.
Int Heart J ; 63(4): 734-741, 2022 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-35831143

RESUMO

Left atrial (LA) dysfunction is known to be a more sensitive prognostic marker than left ventricular (LV) dysfunction in patients with heart failure (HF). Persistent LA overload increases LA stiffness which impairs LA relaxation. The aim of this study was to investigate whether LA filling time is associated with clinical outcomes in patients with HF. Two-dimensional speckle tracking echocardiography (2DSTE) was performed at discharge, to measure LA and LV strain in 179 HF patients admitted to our hospital. The LA filling time index (LAFTI) was defined as the time from onset of the R wave to the peak LA systolic strain divided by the R-R interval. All patients were prospectively followed with cardiac events including cardiac death and rehospitalization for HF. There were 64 cardiac events during a median follow-up period of 451 days. There were no significant differences in heart rate, severity of HF at discharge, etiology of HF, severity of mitral regurgitation, or LV global longitudinal strain between the cardiac event group and no cardiac event group. Patients with cardiac events had significantly higher levels of brain natriuretic peptide (BNP), ratio of the E wave to e' (E/e'), left atrial volume index (LAVI), and lower LAFTI than those without. Kaplan-Meier analysis showed that patients with lower LAFTI were associated with higher cardiac event rates. Multivariate Cox hazard analysis showed that LAFTI was independently associated with the cardiac events after adjustment for confounding factors. In conclusion, LAFTI is a feasible predictor for cardiac events in patients with HF.


Assuntos
Insuficiência Cardíaca , Disfunção Ventricular Esquerda , Função do Átrio Esquerdo/fisiologia , Ecocardiografia/métodos , Átrios do Coração/diagnóstico por imagem , Humanos , Prognóstico , Volume Sistólico
19.
J Cardiol Cases ; 25(6): 389-391, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35685262

RESUMO

In extracardiac Fontan, an epicardial pacemaker implantation has many limitations, especially given that it is highly invasive and a high-risk procedure due to repeat thoracotomy. Herein we illustrate a case with the possibility of transvenous pacing in extracardiac Fontan being less invasive and lower risk transvenous dual-chamber pacemaker implantation by electrophysiological assessment. .

20.
Neural Netw ; 150: 293-312, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35339010

RESUMO

Building a human-like integrative artificial cognitive system, that is, an artificial general intelligence (AGI), is the holy grail of the artificial intelligence (AI) field. Furthermore, a computational model that enables an artificial system to achieve cognitive development will be an excellent reference for brain and cognitive science. This paper describes an approach to develop a cognitive architecture by integrating elemental cognitive modules to enable the training of the modules as a whole. This approach is based on two ideas: (1) brain-inspired AI, learning human brain architecture to build human-level intelligence, and (2) a probabilistic generative model (PGM)-based cognitive architecture to develop a cognitive system for developmental robots by integrating PGMs. The proposed development framework is called a whole brain PGM (WB-PGM), which differs fundamentally from existing cognitive architectures in that it can learn continuously through a system based on sensory-motor information. In this paper, we describe the rationale for WB-PGM, the current status of PGM-based elemental cognitive modules, their relationship with the human brain, the approach to the integration of the cognitive modules, and future challenges. Our findings can serve as a reference for brain studies. As PGMs describe explicit informational relationships between variables, WB-PGM provides interpretable guidance from computational sciences to brain science. By providing such information, researchers in neuroscience can provide feedback to researchers in AI and robotics on what the current models lack with reference to the brain. Further, it can facilitate collaboration among researchers in neuro-cognitive sciences as well as AI and robotics.


Assuntos
Neurociências , Robótica , Inteligência Artificial , Encéfalo , Cognição , Humanos
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