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1.
J Thorac Imaging ; 39(2): 101-110, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37265250

RESUMO

PURPOSE: The purpose of this study was to investigate the effect of integrated evaluation of resting static computed tomography perfusion (CTP) and coronary computed tomography angiography (CCTA)-derived fractional flow reserve (FFR CT ) on therapeutic decision-making and predicting major adverse cardiovascular events (MACEs) in patients with suspected coronary artery disease. MATERIALS AND METHODS: In this post hoc analysis of a prospective trial of CCTA in patients assigned to either CCTA or CCTA plus FFR CT arms, 500 patients in the CCTA plus FFR CT arm were analyzed. Both resting static CTP and FFR CT were evaluated by using the conventional CCTA. Perfusion defects in the myocardial segments with ≥50% degree of stenosis in the supplying vessels were defined as resting static CTP positive, and any vessel with an FFR CT value of ≤0.80 was considered positive. Patients were divided into 3 groups: (1) negative CTP-FFR CT match group (resting static CTP-negative and FFR CT -negative group); (2) mismatch CTP-FFR CT group (resting static CTP-positive and FFR CT -negative or resting static CTP-negative and FFR CT -positive group); and (3) positive CTP-FFR CT match group (resting static CTP-positive and FFR CT -positive group). We compared the revascularization-to-invasive coronary angiography ratio and the MACE rate among 3 subgroups at 1- and 3-year follow-ups. The adjusted Cox hazard proportional model was used to assess the prognostic value of FFR CT and resting static CTP to determine patients at risk of MACE. RESULTS: Patients in the positive CTP-FFR CT match group were more likely to undergo revascularization at the time of invasive coronary angiography compared with those in the mismatch CTP-FFR CT group (81.4% vs 57.7%, P =0.033) and the negative CTP-FFR CT match group (81.4% vs 33.3%, P= 0.001). At 1- and 3-year follow-ups, patients in the positive CTP-FFR CT match group were more likely to have MACE than those in the mismatch CTP-FFR CT group (10.5% vs 4.2%, P= 0.046; 35.6% vs 9.4%, P <0.001) and the negative CTP-FFR CT match group (10.5% vs 0.9%, P <0.001; 35.6% vs 5.4%, P <0.001). A positive CTP-FFR CT match was strongly related to MACE at 1-year (hazard ratio=8.06, P= 0.003) and 3-year (hazard ratio=6.23, P <0.001) follow-ups. CONCLUSION: In patients with suspected coronary artery disease, the combination of FFR CT with resting static CTP could guide therapeutic decisions and have a better prognosis with fewer MACE in a real-world scenario.


Assuntos
Doença da Artéria Coronariana , Estenose Coronária , Reserva Fracionada de Fluxo Miocárdico , Imagem de Perfusão do Miocárdio , Humanos , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/terapia , Imagem de Perfusão do Miocárdio/métodos , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Tomografia Computadorizada por Raios X/métodos , Ensaios Clínicos como Assunto
2.
Opt Express ; 30(20): 35444-35456, 2022 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-36258495

RESUMO

High-order harmonic generation (HHG) from the interaction of ultra-intense laser pulses with atoms is an important tabletop short-wave coherent light source. Accurate quantum simulations of it present large computational difficulties due to multi-electron multidimensional effects. In this paper, the time-dependent response of hydrogen atoms is calculated using a time-series prediction scheme, the HHG spectrum is reconstructed very accurately. The accuracy of the forecasting is further improved by using a neural network scheme. This scheme is also applied to the simulation of the harmonic emission on multi-electron systems, and the applicability of the scheme is confirmed by the harmonic calculation of complex systems. This method is expected to simulate the nonlinear dynamic process of multi-electron atoms and molecules irradiated by intense laser pulses quickly and accurately.

3.
J Phys Chem A ; 125(3): 770-776, 2021 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-33433217

RESUMO

The temporal delayed orthogonal pulse pairs generated by the phase shaping technique are used to study the coherent control of the rotational wave packet dynamics in air. By continuously changing the intrapulse delay of the pump pulse, we measured the corresponding revival signals and obtained a two-dimensional rotational coherent spectrum (2D RCS). An additive property of the rotational dynamics is observed from the revival signals. Moreover, combining with the coherent control model, we find that the 2D RCS can be used to demonstrate the control over the underlying Raman rotational excitation. A beat frequency-dependent oscillation of each rotational transition is obtained. The transition process is revealed from the Fourier transformation about the pump delay. The scheme of this work can be used for further control and detection of the rotational wave packet and can be extended to other molecular dynamic researches.

4.
BMJ Case Rep ; 20122012 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-22665866

RESUMO

An older male with multiple medical comorbidities presented to the emergency room after 3 days of worsening right upper quadrant pain. The patient had an elevated white blood cell count and mildly elevated liver functions. Initial ultrasound was equivocal and further imaging with CT scan was obtained. The CT scan was read as suggestive of cholecystitis, however a hepatobiliary scintigraphy (HIDA) scan was ordered for confirmation, as the patient was a poor operative candidate. The HIDA demonstrated no bile duct or small bowel activity on initial images or delays, however a classic 'hot rim' sign was present, confirming acute cholecystitis. The patient ultimately underwent percutaneous cholecystostomy with drainage for treatment where acute cholecystitis was confirmed. Upon retrospective review, the CT demonstrated hyperaemia surrounding the gallbladder fossa, which is the CT scan equivalent of a scintigraphic 'hot rim' sign. This is an uncommon example of a radiologic sign correlation between multiple imaging modalities.


Assuntos
Colecistite Aguda/diagnóstico por imagem , Idoso , Colecistite Aguda/diagnóstico , Colecistite Aguda/cirurgia , Colecistografia , Colecistostomia , Diagnóstico Diferencial , Vesícula Biliar/diagnóstico por imagem , Humanos , Masculino , Cintilografia , Tomografia Computadorizada por Raios X
5.
Mech Dev ; 116(1-2): 169-72, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12128218

RESUMO

Patterning of the central nervous system is regulated by a signaling center located at the midbrain-hindbrain boundary (MHB), or isthmus organizer. Fibroblast growth factors secreted from the MHB are required and sufficient to direct the ordered growth and regionalization of the midbrain and anterior hindbrain. In an unbiased secretion cloning screen of Xenopus gastrula embryos we identified a novel gene, which we designated as Isthmin (xIsm) due to its prominent expression at the MHB. xIsm encodes a secreted protein of 449 amino acids containing one copy of the thrombospondin type 1 repeat (TSR). We also found orthologous Isthmin genes in human (hIsm) and mouse (mIsm), as well as a gene encoding an Isthmin-like human unknown protein (hIsm-l). The conservation of a unique carboxy-terminal region between hIsm and hIsm-l suggests that Isthmin is the founding member of a new family of secreted proteins. xIsm was strongly expressed maternally in the Xenopus egg and showed zygotic expression in the ventral blastopore lip, notochord, and MHB. Additional expression domains were detected in neural crest, ear vesicle, and developing blood islands. Interestingly, xIsm was co-expressed with Fibroblast growth factor-8 (xFgf-8) at multiple sites including the MHB, indicating that these two genes are part of a synexpression group which also includes sprouty and sef homologs.


Assuntos
Fatores de Crescimento de Fibroblastos/genética , Mesencéfalo/embriologia , Proteínas do Tecido Nervoso/genética , Rombencéfalo/embriologia , Xenopus/embriologia , Xenopus/genética , Sequência de Aminoácidos , Animais , Fator 8 de Crescimento de Fibroblasto , Humanos , Hibridização In Situ , Camundongos , Dados de Sequência Molecular , Proteínas do Tecido Nervoso/metabolismo , Organizadores Embrionários , Homologia de Sequência de Aminoácidos
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