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1.
Opt Express ; 31(11): 17782-17791, 2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-37381503

RESUMO

Multipartite entanglements are essential resources for proceeding tasks in quantum information science and technology. However, generating and verifying them present significant challenges, such as the stringent requirements for manipulations and the need for a huge number of building-blocks as the systems scale up. Here, we propose and experimentally demonstrate the heralded multipartite entanglements on a three-dimensional photonic chip. Integrated photonics provide a physically scalable way to achieve an extensive and adjustable architecture. Through sophisticated Hamiltonian engineering, we are able to control the coherent evolution of shared single photon in the multiple spatial modes, dynamically tuning the induced high-order W-states of different orders in a single photonic chip. Using an effective witness, we successfully observe and verify 61-partite quantum entanglements in a 121-site photonic lattice. Our results, together with the single-site-addressable platform, offer new insights into the accessible size of quantum entanglements and may facilitate the developments of large-scale quantum information processing applications.

2.
J Endovasc Ther ; : 15266028221111295, 2022 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-35852439

RESUMO

PURPOSE: False lumen (FL) expansion often occurs in type B aortic dissection (TBAD) and has been associated with the presence of re-entry tears. This longitudinal study aims to elucidate the role of re-entry tears in the progression of TBAD using a controlled swine model, by assessing aortic hemodynamics through combined imaging and computational modeling. MATERIALS AND METHODS: A TBAD swine model with a primary entry tear at 7 cm distal to the left subclavian artery was created in a previous study. In the current study, reintervention was carried out in this swine model to induce 2 additional re-entry tears of approximately 5 mm in diameter. Computed tomography (CT) and 4-dimensional (4D) flow magnetic resonance imaging (MRI) scans were taken at multiple follow-ups before and after reintervention. Changes in aortic volume were measured on CT scans, and hemodynamic parameters were evaluated based on dynamic data acquired with 4D-flow MRI and computational fluid dynamics simulations incorporating all available in vivo data. RESULTS: Morphological analysis showed FL growth of 20% following the initial TBAD-growth stabilized after the creation of additional tears and eventually FL volume reduced by 6%. Increasing the number of re-entry tears from 1 to 2 caused flow redistribution, with the percentage of true lumen (TL) flow increasing from 56% to 78%; altered local velocities; reduced wall shear stress surrounding the tears; and led to a reduction in FL pressure and pressure difference between the 2 lumina. CONCLUSION: This study combined extensive in vivo imaging data with sophisticated computational methods to show that additional re-entry tears can alter dissection hemodynamics through redistribution of flow between the TL and FL. This helps to reduce FL pressure, which could potentially stabilize aortic growth and lead to reversal of FL expansion. This work provides a starting point for further study into the use of fenestration in controlling undesirable FL expansion. CLINICAL IMPACT: Aortic growth and false lumen (FL) patency are associated with the presence of re-entry tears in type B aortic dissection (TBAD) patients. Guidelines on how to treat re-entry tears are lacking, especially with regards to the control and prevention of FL expansion. Through a combined imagining and computational hemodynamics study of a controlled swine model, we found that increasing the number of re-entry tears reduced FL pressure and cross lumen pressure difference, potentially stabilising aortic growth and leading to FL reduction. Our findings provide a starting point for further study into the use of fenestration in controlling undesirable FL expansion.

3.
Pharm Res ; 39(1): 41-56, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35044591

RESUMO

PURPOSE: This study establishes a multiphysics simulation platform for both conventional and targeted thrombolysis using tissue plasminogen activator (tPA). Based on our computational results, the effects of therapeutic parameters on the dynamics of thrombolysis and the risk of side effects are investigated. METHODS: The model extends our previously developed one-dimensional(1D) mathematical models for fibrinolysis by incorporating targeted thrombolysis. It consists of two parts: (i) a coupled mathematical model of systemic pharmacokinetics (PK) and pharmacodynamics (PD) and local PD in a 1D occluded artery, and (ii) a mechanistic model for a targeted thrombolytic system via activated platelet-targeted tPA-loaded nanovesicles (tPA-NV), with model parameters derived from our in vitro experiments. A total of 16 therapeutic scenarios are simulated by varying the clot location and composition as well as the dosing regimen with free tPA or tPA-NV. RESULTS: Our simulation results indicate that tPA-NV offers several advantages over free tPA for thrombolysis. It reduces systemic exposure of tPA, thereby minimising the risk of bleeding complications. Simulations with different tPA-NV doses reveal that tPA-NV at 10% of the recommended dose can be as effective as the standard regimen with the full recommended dose of free tPA, demonstrating the potential of our tPA-NV as a new thrombolytic strategy with a reduced tPA dose. Moreover, faster recanalisation can be achieved with tPA-NV, especially for platelet-rich(or fibrin-poor) clots. CONCLUSIONS: Our simulation platform for thrombolysis with well-tuned model parameters can be used to evaluate and optimise treatment regimens of existing and new thrombolytic therapies via benefit/risk assessment under various therapeutic scenarios.


Assuntos
Fibrinólise , Ativador de Plasminogênio Tecidual , Fibrinolíticos/farmacologia , Nanomedicina , Terapia Trombolítica/métodos , Ativador de Plasminogênio Tecidual/farmacologia , Ativador de Plasminogênio Tecidual/uso terapêutico
4.
Opt Express ; 29(5): 7746-7756, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33726270

RESUMO

The implementation of quantum information technologies requires the development of integrated quantum chips. Femtosecond laser direct writing (FLDW) waveguides and superconducting nanowire single-photon detectors (SNSPDs) have been widely applied in integrated quantum photonic circuits. In this work, a novel FLDW waveguide-coupled SNSPD was designed and realized by integrating FLDW waveguides and conventional SNSPDs together. Through a COMSOL simulation, a waveguide end face-nanowire optical coupling structure was designed and verified. The simulation results showed that the FLDW waveguide-coupled SNSPD device, which had a target wavelength of 780 nm, can achieve 87% optical absorption. Then the preparation process of the FLDW waveguide-coupled SNSPD device was developed, and the fabricated device achieved a system detection efficiency of 1.7% at 10 Hz dark count rate. Overall, this method provides a feasible single-photon detector solution for future on-chip integrated quantum photonic experiments and applications.

5.
Phys Rev Lett ; 126(11): 110501, 2021 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-33798380

RESUMO

Quantum computation promises intrinsically parallel information processing capacity by harnessing the superposition and entanglement of quantum states. However, it is still challenging to realize universal quantum computation due that the reliability and scalability are limited by unavoidable noises on qubits. Nontrivial topological properties like quantum Hall phases are found capable of offering protection, but require stringent conditions of topological band gaps and broken time-reversal symmetry. Here, we propose and experimentally demonstrate a symmetry-induced error filtering scheme, showing a more general role of geometry in protection mechanism and applications. We encode qubits in a superposition of two spatial modes on a photonic Lieb lattice. The geometric symmetry endows the system with topological properties featuring a flat band touching, leading to distinctive transmission behaviors of π-phase qubits and 0-phase qubits. The geometry exhibits a significant effect on filtering phase errors, which also enables it to monitor phase deviations in real time. The symmetry-induced error filtering can be a key element for encoding and protecting quantum states, suggesting an emerging field of symmetry-protected universal quantum computation and noisy intermediate-scale quantum technologies.

6.
J Biomech Eng ; 143(8)2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-33764388

RESUMO

A computational approach is used to investigate potential risk factors for distal stent graft-induced new entry (dSINE) in aortic dissection (AD) patients. Patient-specific simulations were performed based on computed tomography images acquired from six AD patients (three dSINE and three non-dSINE) to analyze the correlation between anatomical characteristics and stress/strain distributions. Sensitivity analysis was carried out using idealized models to independently assess the effect of stent graft length, stent tortuosity and wedge apposition angle at the landing zone on key biomechanical variables. Mismatch of biomechanical properties between the stented and nonstented regions led to high stress at the distal stent graft-vessel interface in all patients, as well as shear strain in the neighboring region, which coincides with the location of tear formation. Stress was observed to increase with the increase of stent tortuosity (from 263 kPa at a tortuosity angle of 50 deg to 313 kPa at 30 deg). It was further amplified by stent graft landing at the inflection point of a curve. Malapposition of the stent graft led to an asymmetrical segment within the aorta, therefore changing the location and magnitude of the maximum von Mises stress substantially (up to +25.9% with a +25 deg change in the distal wedge apposition angle). In conclusion, stent tortuosity and wedge apposition angle serve as important risk predictors for dSINE formation in AD patients.


Assuntos
Stents
7.
Arch Gynecol Obstet ; 303(6): 1501-1511, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33471216

RESUMO

PURPOSE: Adenomyosis is a diffuse or localized disease. Our previous study has indicated that tanshinone IIA (TSIIA) inhibits the proliferation, migration, and induces apoptosis of ectopic endometrial stromal cells (EESCs) of adenomyosis. However, the complex molecular mechanism of TSIIA in adenomyosis remains unclear. The objective of this study was to explore the complex molecular mechanism of TSIIA on EESCs. METHODS: In our present study, we used the proteomics approach iTRAQ (isobaric tags for relative and absolute quantitation) combined with LC-MS/MS (liquid chromatography-mass spectrometry) to investigate changes in the protein profile of EESCs treated with TSIIA. Differential proteins were analyzed by employing bioinformatics tools and the Kyoto Encyclopedia of Genes and Genomes (KEGG) database. In TSIIA treated EESCs, the protein expression levels of TNFRSF10D, PLEKHM1, FECH, and TPM1A were detected by western blotting. RESULTS: Quantitative results revealed 267 significantly differential proteins in TSIIA pretreated EESCs. Gene Ontology (GO) analysis presented an overview of dysregulated proteins in the biological process (BP), cell component (CC), and molecular function (MF) categories. Interestingly, we observed that differential proteins in the extracellular matrix (ECM)-receptor interaction pathway and estrogen signaling pathway were all involved in the focal adhesion pathway, which plays essential roles in the TSIIA-mediated inhibition of EESC proliferation and migration. Furthermore, some significantly differential proteins, which may be potential targets for the treatment of adenomyosis in the future, were validated by western blotting. CONCLUSIONS: Our study provides a useful method to detect the detailed mechanism underlying the efficacy of TSIIA on EESCs.


Assuntos
Adenomiose , Abietanos , Proliferação de Células , Cromatografia Líquida , Feminino , Humanos , Proteômica , Células Estromais , Espectrometria de Massas em Tandem
8.
Int J Environ Health Res ; 31(1): 54-62, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31184496

RESUMO

To evaluate the association between ambient air pollution and hyperuricemia, we prospectively followed 1748 traffic police officers without hyperuricemia at baseline (2009-2014) from 11 districts in Guangzhou, China. We calculated six-year average PM10, SO2 and NO2 concentrations using data collected from air monitoring stations. The hazard ratios for hyperuricemia per 10 µg/m3 increase in air pollutants were 1.46 (95% CI: 1.28-1.68) for PM10, 1.23 (95% CI: 1.00-1.51) for SO2, and 1.43 (95% CI: 1.26-1.61) for NO2. We also identified changes in the ratio of serum uric acid to serum creatinine concentrations (ua/cre) per 10 µg/m3 increase in air pollutants as 11.54% (95% CI: 8.14%-14.93%) higher for PM10, 5.09% (95% CI: 2.76%-7.42%) higher for SO2, and 5.13% (95% CI: 2.35%-7.92%) higher for NO2, respectively. Long-term exposure to ambient air pollution was associated with a higher incidence of hyperuricemia and an increase in ua/cre among traffic police officers.


Assuntos
Poluentes Atmosféricos/efeitos adversos , Poluição do Ar/efeitos adversos , Exposição Ambiental/efeitos adversos , Hiperuricemia/epidemiologia , Ácido Úrico/sangue , Adulto , China/epidemiologia , Feminino , Humanos , Hiperuricemia/induzido quimicamente , Incidência , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Prospectivos
9.
J Endovasc Ther ; 27(3): 396-404, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32364001

RESUMO

Purpose: To report a study that assesses the influence of the distance between the distal end of a thoracic stent-graft and the first reentry tear (SG-FRT) on the progression of false lumen (FL) thrombosis in patients who underwent thoracic endovascular aortic repair (TEVAR). Materials and Methods: Three patient-specific geometrical models were reconstructed from postoperative computed tomography scans. Two additional models were created by artificially changing the SG-FRT distance in patients 1 and 2. In all 5 models, computational fluid dynamics simulations coupled with thrombus formation modeling were performed at physiological flow conditions. Predicted FL thrombosis was compared to follow-up scans. Results: There was reduced false lumen flow and low time-averaged wall shear stress (TAWSS) in patients with large SG-FRT distances. Predicted thrombus formation and growth were consistent with follow-up scans for all patients. Reducing the SG-FRT distance by 30 mm in patient 1 increased the flow and time-averaged wall shear stress in the upper abdominal FL, reducing the thrombus volume by 9.6%. Increasing the SG-FRT distance in patient 2 resulted in faster thoracic thrombosis and increased total thrombus volume. Conclusion: The location of reentry tears can influence the progression of FL thrombosis following TEVAR. The more distal the reentry tear in the aorta the more likely it is that FL thrombosis will occur. Hence, the distal landing zone of the stent-graft should be chosen carefully to ensure a sufficient SG-FRT distance.


Assuntos
Aneurisma da Aorta Torácica/cirurgia , Dissecção Aórtica/cirurgia , Implante de Prótese Vascular , Procedimentos Endovasculares , Hemodinâmica , Trombose/fisiopatologia , Dissecção Aórtica/diagnóstico por imagem , Dissecção Aórtica/fisiopatologia , Aneurisma da Aorta Torácica/diagnóstico por imagem , Aneurisma da Aorta Torácica/fisiopatologia , Aortografia , Prótese Vascular , Implante de Prótese Vascular/efeitos adversos , Implante de Prótese Vascular/instrumentação , Angiografia por Tomografia Computadorizada , Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/instrumentação , Humanos , Modelos Cardiovasculares , Modelagem Computacional Específica para o Paciente , Desenho de Prótese , Fatores de Risco , Stents , Trombose/diagnóstico por imagem , Resultado do Tratamento , Remodelação Vascular
10.
Eur J Vasc Endovasc Surg ; 58(3): 415-425, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31337584

RESUMO

OBJECTIVE: Haemodynamic and geometric factors play pivotal roles in the propagation of acute type B aortic dissection (TBAD). The aim of this study was to evaluate the association between dissection level within all aortic layers and the propagation of acute TBAD in porcine aorta. METHODS: In twelve pigs, two models of TBAD were created. In model A (n = 6), the aortic wall tear was superficial and close to the intima (thin intimal flap), whereas in model B (n = 6) it was deep and close to the adventitia (thick intimal flap). Dissection propagation was evaluated using angiography or computed tomography scans, and the haemodynamic measurements were acquired using Doppler wires. Most pigs were followed up at 1, 3, 6, 12, 18, and up to 24 months; four animals were euthanised at three and six months, respectively (two from each group). RESULTS: Both models were successfully created. No statistical difference was observed for the median antegrade propagation distance intra-operatively between the two models (p = .092). At 24 months, the longitudinal propagation distance was significantly greater in model B than in model A (p = .016). No statistical difference in retrograde propagation was noted (p = .691). Over time, aortic wall dissection progressed most notably over the first three months in model A, whereas it continued over the first 12 months in model B. Flow velocity was significantly greater in the true lumen than in false lumen at the level of the primary tear (p = .001) and in the middle of the dissection (p = .004). The histopathological images at three and six months demonstrated the fibres were stretched linearly at the outside wall of false lumen in both models, while the depth of intimal tears developed to be superficial and similar at the distal dissection. CONCLUSION: In this swine model of TBAD, a deeper intimal tear resulted in greater dissection propagation.


Assuntos
Aorta Torácica/diagnóstico por imagem , Aneurisma da Aorta Torácica/diagnóstico , Dissecção Aórtica/diagnóstico , Velocidade do Fluxo Sanguíneo/fisiologia , Doença Aguda , Dissecção Aórtica/fisiopatologia , Animais , Aorta Torácica/fisiopatologia , Aneurisma da Aorta Torácica/fisiopatologia , Angiografia por Tomografia Computadorizada/métodos , Modelos Animais de Doenças , Progressão da Doença , Feminino , Masculino , Prognóstico , Índice de Gravidade de Doença , Suínos , Ultrassonografia Doppler/métodos
11.
J Vasc Surg ; 67(4): 1026-1033.e2, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29097043

RESUMO

OBJECTIVE: Stent graft (SG)-induced new entry (SINE) and retrograde type A dissection (RTAD) are serious device-related complications occurring after thoracic endovascular aortic repair (TEVAR) for Stanford type B aortic dissection (TBAD) and may lead to endograft-related complications including retrograde dissection and death. The purpose of this study was to investigate the incidence and risk factors for the development of RTAD and SINE after TEVAR for TBAD and to identify the complications associated with this. METHODS: From April 2005 to October 2013, there were 997 patients who underwent TEVAR for TBAD; 852 were followed up (0-6 years; mean, 2.6 years), and 59 SINEs developed in 53 patients. The oversizing ratio and incidence of RTAD and SINE were compared between proximal bare stent (PBS) and non-PBS groups and RTAD and SINE and non-RTAD and non-SINE groups. The baseline characteristics and SG configurational factors potentially affecting both RTAD and distal SINE were analyzed. RESULTS: There was no significant difference between PBS and non-PBS groups in the incidence of RTAD. A greater oversizing ratio was related to a higher distal SINE rate. SINE was seen more frequently in smokers and in patients with hypertension, Marfan syndrome, and TEVAR in the chronic phase and less frequently in complicated dissection cases. Device-related factors for SINE were SG with a connecting bar and SG length <165 mm. The SG length <165 mm increased the overall proximal and distal SINE incidence in multivariate analysis. CONCLUSIONS: The presence of a PBS is not associated with a higher RTAD rate, whereas the use of an SG with a connecting bar and length <165 mm increases the risk of RTAD and SINE after TEVAR.


Assuntos
Aorta Torácica/cirurgia , Aneurisma da Aorta Torácica/epidemiologia , Dissecção Aórtica/epidemiologia , Implante de Prótese Vascular/efeitos adversos , Implante de Prótese Vascular/instrumentação , Prótese Vascular , Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/instrumentação , Stents , Adulto , Idoso , Idoso de 80 Anos ou mais , Dissecção Aórtica/diagnóstico por imagem , Aorta Torácica/diagnóstico por imagem , Aneurisma da Aorta Torácica/diagnóstico por imagem , Aortografia/métodos , Distribuição de Qui-Quadrado , China/epidemiologia , Angiografia por Tomografia Computadorizada , Feminino , Humanos , Incidência , Modelos Logísticos , Masculino , Metais , Pessoa de Meia-Idade , Análise Multivariada , Desenho de Prótese , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
12.
J Endovasc Ther ; 25(5): 571-577, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30056791

RESUMO

PURPOSE: To explore the potential role of morphological factors and wall stress in the formation of stent-graft-induced new entries (SINE) based on computed tomography (CT) images after thoracic endovascular aortic repair (TEVAR). CASE REPORT: Two female patients aged 59 years (patient 1) and 44 years (patient 2) underwent TEVAR for type B dissection in the chronic (patient 1) or subacute (patient 2) phase. CT scans at 3-month follow-up showed varying degrees of false lumen thrombosis in both patients. At 14-month follow-up, a SINE was observed in patient 1 while the dissected aorta in the other patient remained stable. Morphological and finite element analyses were performed based on the first follow-up CT images. The computational results showed that the SINE patient had higher stent-graft tortuosity than the non-SINE patient and much higher wall stress in the region close to the distal SINE. CONCLUSION: This case study suggests that high stent-graft tortuosity can lead to high wall stress, which is potentially linked to the formation of SINE. Further large population-based studies are needed to confirm this preliminary finding.


Assuntos
Aneurisma da Aorta Torácica/cirurgia , Dissecção Aórtica/cirurgia , Implante de Prótese Vascular/instrumentação , Prótese Vascular , Procedimentos Endovasculares/instrumentação , Stents , Adulto , Dissecção Aórtica/diagnóstico por imagem , Dissecção Aórtica/fisiopatologia , Aneurisma da Aorta Torácica/diagnóstico por imagem , Aneurisma da Aorta Torácica/fisiopatologia , Aortografia/métodos , Implante de Prótese Vascular/efeitos adversos , Angiografia por Tomografia Computadorizada , Procedimentos Endovasculares/efeitos adversos , Feminino , Análise de Elementos Finitos , Humanos , Pessoa de Meia-Idade , Modelagem Computacional Específica para o Paciente , Projetos Piloto , Fluxo Sanguíneo Regional , Estresse Mecânico , Resultado do Tratamento
13.
Opt Express ; 24(12): 12607-16, 2016 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-27410282

RESUMO

Quantum interference and quantum correlation, as two main features of quantum optics, play an essential role in quantum information applications, such as multi-particle quantum walk and boson sampling. While many experimental demonstrations have been done in one-dimensional waveguide arrays, it remains unexplored in higher dimensions due to tight requirement of manipulating and detecting photons in large-scale. Here, we experimentally observe non-classical correlation of two identical photons in a fully coupled two-dimensional structure, i.e. photonic lattice manufactured by three-dimensional femtosecond laser writing. Photon interference consists of 36 Hong-Ou-Mandel interference and 9 bunching. The overlap between measured and simulated distribution is up to 0.890 ± 0.001. Clear photon correlation is observed in the two-dimensional photonic lattice. Combining with controllably engineered disorder, our results open new perspectives towards large-scale implementation of quantum simulation on integrated photonic chips.

14.
J Endovasc Ther ; 23(5): 809-20, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27225213

RESUMO

PURPOSE: To quantify the hemodynamic impact of a flared renal stent on the performance of fenestrated stent-grafts (FSGs) by analyzing flow patterns and wall shear stress-derived parameters in flared and nonflared FSGs in different physiologic scenarios. METHODS: Hypothetical models of FSGs were created with and without flaring of the proximal portion of the renal stent. Flared FSGs with different dilation angles and protrusion lengths were examined, as well as a nonplanar flared FSG to account for lumbar curvature. Laminar and pulsatile blood flow was simulated by numerically solving Navier-Stokes equations. A physiologically realistic flow rate waveform was prescribed at the inlet, while downstream vasculature was modeled using a lumped parameter 3-element windkessel model. No slip boundary conditions were imposed at the FSG walls, which were assumed to be rigid. While resting simulations were performed on all the FSGs, exercise simulations were also performed on a flared FSG to quantify the effect of flaring in different physiologic scenarios. RESULTS: For cycle-averaged inflow of 2.94 L/min (rest) and 4.63 L/min (exercise), 27% of blood flow was channeled into each renal branch at rest and 21% under exercise for all the flared FSGs examined. Although the renal flow waveform was not affected by flaring, flow within the flared FSGs was disturbed. This flow disturbance led to high endothelial cell activation potential (ECAP) values at the renal ostia for all the flared geometries. Reducing the dilation angle or protrusion length and exercise lowered the ECAP values for flared FSGs. CONCLUSION: Flaring of renal stents has a negligible effect on the time dependence of renal flow rate waveforms and can maintain sufficient renal perfusion at rest and exercise. Local flow patterns are, however, strongly dependent on renal flaring, which creates a local flow disturbance and may increase the thrombogenicity at the renal ostia. Smaller dilation angles, shorter protrusion lengths, and moderate lower limb exercise are likely to reduce the risk of thrombosis in flared geometries.


Assuntos
Aneurisma da Aorta Abdominal/cirurgia , Implante de Prótese Vascular/instrumentação , Prótese Vascular , Procedimentos Endovasculares/instrumentação , Exercício Físico , Hemodinâmica , Artéria Renal/cirurgia , Descanso , Stents , Aneurisma da Aorta Abdominal/fisiopatologia , Velocidade do Fluxo Sanguíneo , Implante de Prótese Vascular/efeitos adversos , Simulação por Computador , Procedimentos Endovasculares/efeitos adversos , Humanos , Teste de Materiais , Modelos Cardiovasculares , Desenho de Prótese , Artéria Renal/fisiopatologia , Circulação Renal , Trombose/etiologia , Trombose/fisiopatologia , Fatores de Tempo
15.
Bioorg Med Chem Lett ; 26(4): 1310-3, 2016 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-26786699

RESUMO

A series of novel α-amino phosphonate derivatives containing a uracil moiety 3a-3l were designed and synthesized by a Lewis acid (magnesium perchlorate) catalyzed the Kabachnik-Fields reaction. The bioassays {in vitro, in vivo [Glass House 1 (GH1) and Glass House 2 (GH2)]} showed that most of compounds 3 exhibited excellent and selective herbicidal activities; for example, in GH1 test, compounds 3b, 3d, 3f, 3h and 3j showed excellent and wide spectrum herbicidal activities at the dose of 1000 g/ha, and compounds 3b and 3j exhibited 100% inhibition activities against the four plants in both post- and pre-emergence treatments. Moreover, most of compounds 3 showed higher inhibition against Amaranthus retroflexus and Digitaria sanguinalis than Glyphosate did in pre-emergence treatment. In GH2 test, the four compounds (3b, 3d, 3h and 3j) exhibited 100% inhibition against Solanum nigrum, Amaranthus retroflexus and Ipomoea hederacea in post-emergence treatment and displayed 100% inhibition against Solanum nigrum, Amaranthus retroflexus in pre-emergence treatment at the rate of 250 g/ha, and compound 3b showed the best and broad spectrum herbicidal activities against the six test plants. However, the four compounds displayed weaker herbicidal activities against Lolium perenne and Echinochloa crus-galli than the other four plants at the rate of 250 g/ha in both pre- and post-emergence treatments. So, compounds 3 can be used as a lead compound for further structure optimization for developing potential selective herbicidal agent. Their preliminary structure-activity relationships were also investigated.


Assuntos
Herbicidas/síntese química , Ácidos Fosforosos/química , Uracila/química , Amaranthus/efeitos dos fármacos , Digitaria/efeitos dos fármacos , Glicina/análogos & derivados , Glicina/toxicidade , Herbicidas/química , Herbicidas/toxicidade , Ipomoea/efeitos dos fármacos , Ácidos Fosforosos/síntese química , Ácidos Fosforosos/toxicidade , Solanum nigrum/efeitos dos fármacos , Relação Estrutura-Atividade , Glifosato
16.
J Math Biol ; 73(5): 1205-1226, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27007280

RESUMO

Aortic dissection is a major aortic catastrophe with a high morbidity and mortality risk caused by the formation of a tear in the aortic wall. The development of a second blood filled region defined as the "false lumen" causes highly disturbed flow patterns and creates local hemodynamic conditions likely to promote the formation of thrombus in the false lumen. Previous research has shown that patient prognosis is influenced by the level of thrombosis in the false lumen, with false lumen patency and partial thrombosis being associated with late complications and complete thrombosis of the false lumen having beneficial effects on patient outcomes. In this paper, a new hemodynamics-based model is proposed to predict the formation of thrombus in Type B dissection. Shear rates, fluid residence time, and platelet distribution are employed to evaluate the likelihood for thrombosis and to simulate the growth of thrombus and its effects on blood flow over time. The model is applied to different idealized aortic dissections to investigate the effect of geometric features on thrombus formation. Our results are in qualitative agreement with in-vivo observations, and show the potential applicability of such a modeling approach to predict the progression of aortic dissection in anatomically realistic geometries.


Assuntos
Aneurisma Aórtico/patologia , Dissecção Aórtica/patologia , Modelos Biológicos , Trombose/patologia , Humanos
17.
J Endovasc Ther ; 22(4): 578-90, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25979146

RESUMO

PURPOSE: To report a computational study assessing the hemodynamic outcomes of branched stent-grafts (BSGs) for different anatomic variations. METHODS: Idealized models of BSGs and fenestrated stent-grafts (FSGs) were constructed with different visceral takeoff angles (ToA) and lateral aortic neck angles. ToA was defined as the angle between the centerlines of the main stent-graft and side branch, with 90° representing normal alignment, and 30° and 120° representing angulated side branches. Computational simulations were performed by solving the conservation equations governing the blood flow under physiologically realistic conditions. RESULTS: The largest renal flow recirculation zones (FRZs) were observed in FSGs at a ToA of 30°, and the smallest FRZ was also found in FSGs (at a ToA of 120°). For straight-neck stent-grafts with a ToA of 90°, mean flow in each renal artery was 0.54, 0.46, and 0.62 L/min in antegrade BSGs, retrograde BSGs, and FSGs, respectively. For angulated stent-grafts, the corresponding values were 0.53, 0.48, and 0.63 L/min. All straight-neck stent-grafts experienced equal cycle-averaged displacement forces of 1.25, 1.69, and 1.95 N at ToAs of 30°, 90°, and 120°, respectively. Angulated main stent-grafts experienced an equal cycle-averaged displacement force of 3.6 N. CONCLUSION: The blood flow rate in renal arteries depends on the configuration of the stent-graft, with an FSG giving maximum renal flow and a retrograde BSG resulting in minimum renal flow. Nevertheless, the difference was small, up to 0.09 L/min. Displacement forces exerted on stent-grafts are very sensitive to lateral neck angle but not on the configuration of the stent-graft.


Assuntos
Aneurisma da Aorta Abdominal/fisiopatologia , Aneurisma da Aorta Abdominal/cirurgia , Velocidade do Fluxo Sanguíneo/fisiologia , Implante de Prótese Vascular/métodos , Prótese Vascular , Procedimentos Endovasculares/métodos , Stents , Humanos , Resultado do Tratamento
18.
Metab Brain Dis ; 30(4): 1027-34, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25875132

RESUMO

Type 2 diabetes mellitus (T2DM) is associated with cognitive dysfunction. Previous studies have reported the relationship between cerebral metabolite changes and glucose levels. However, the specific aspects of cognition that are affected by metabolic changes in T2DM- related cognitive impairment remain undetermined. In this study, 188 T2DM patients and 266 controls were recruited. Proton magnetic resonance spectra with a single voxel stimulated echo acquisition mode (STEAM) were acquired from the left hippocampus and the frontal lobe. Presence of T2DM negatively affected the scores of Mini-Mental State Examination (MMSE), sub-tests (i.e., attention and language) of MMSE, Montreal Cognitive Assessment (MoCA) according to the Beijing version, and sub-tests (i.e., visuospatial/executive reasoning, attention, and language) of MoCA, rather than the Wechsler Memory Scale - Revised in China (WMS-RC), and all memory sub-tests contained with the MMSE and MoCA frameworks. T2DM positively affected creatine and myoinositol peak areas from the left hippocampus, rather than metabolites in the left frontal lobe. Negative correlations were shown between the left hippocampal myoinositol levels and language scores, and between the left hippocampal creatine levels and visuospatial/executive scores in T2DM. These findings suggest that T2DM may be an independent risk factor for cognitive impairment. Further, the cognitive domains of visuospatial /executive reasoning, attention and language may be predominantly impaired in the early phases of T2DM-related cognitive impairment. In addition, left hippocampal myoinositol and creatine concentrations were associated with cognitive impairment in patients with T2DM.


Assuntos
Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/metabolismo , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/metabolismo , Hipocampo/metabolismo , Idoso , China/epidemiologia , Transtornos Cognitivos/epidemiologia , Diabetes Mellitus Tipo 2/epidemiologia , Feminino , Hipocampo/patologia , Humanos , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos
19.
J Urol ; 192(5): 1410-7, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24769027

RESUMO

PURPOSE: We evaluated whether glans preserving surgery would be more helpful for patients to regain satisfactory sexual competency postoperatively than conventional partial amputation. MATERIALS AND METHODS: From 2004 to 2012 at 4 centers a total of 135 men treated with glans preserving surgery and 36 treated with partial amputation were selected for evaluation from a total of 273 consecutive patients with penile cancer. Subjective evaluation for patient sexual performance was investigated using the IIEF-15. Objective evaluation was done using the audiovisual sexual stimulation test with the RigiScan® Plus. The degree of satisfaction with penile appearance, and patient confidence and partner acceptability for intercourse were evaluated by 5-point scales. RESULTS: Patients treated with glans preserving surgery had better performance in 4 IIEF-15 domains (erectile function, orgasmic function, intercourse satisfaction and overall satisfaction) and 1 RigiScan parameter (tip rigidity) (each p <0.01). They also had significantly higher appearance satisfaction (64.4% vs 13.9%) and intercourse confidence (55.6% vs 5.6%) than men who underwent partial amputation. Sexual partners in the glans preserving group also showed significantly higher appearance satisfaction (51.1% vs 5.6%) and intercourse acceptability (37.8% vs 16.7%) than in the partial amputation group. CONCLUSIONS: Glans preserving surgery effectively preserves the functional anatomy and cosmetic appearance of the glans penis. Glans preservation contributes to minimizing postoperative erectile dysfunction and negative psychological impediments, and promotes return to satisfactory sexual performance. Patients treated with glans preservation have more advantages in obtaining sexual acceptance from their partners than those who undergo amputation.


Assuntos
Pênis/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Sexualidade/fisiologia , Procedimentos Cirúrgicos Urológicos Masculinos , Adulto , Idoso , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Satisfação do Paciente , Ereção Peniana/fisiologia , Período Pós-Operatório , Estudos Retrospectivos , Resultado do Tratamento
20.
Mutat Res ; 761: 49-52, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24472300

RESUMO

The catalytic subunit of DNA polymerase epsilon (POLE1) functions primarily in nuclear DNA replication and repair. Recently, POLE1 mutations were detected frequently in colorectal and endometrial carcinomas while with lower frequency in several other types of cancer, and the p.P286R and p.V411L mutations were the potential mutation hotspots in human cancers. Nevertheless, the mutation frequency of POLE1 in ovarian cancer still remains largely unknown. Here, we screened a total of 251 Chinese samples with distinct subtypes of ovarian carcinoma for the presence of POLE1 hotspot mutations by direct sequencing. A heterozygous somatic POLE1 mutation, p.S297F (c.890C>T), but not p.P286R and p.V411L hotspot mutations observed in other cancer types, was identified in 3 out of 37 (8.1%) patients with ovarian endometrioid carcinoma; this mutation was evolutionarily highly conserved from Homo sapiens to Schizosaccharomyces. Of note, the POLE1 mutation coexisted with mutation in the ovarian cancer-associated PPP2R1A (protein phosphatase 2, regulatory subunit A, α) gene in a 46-year-old patient, who was also diagnosed with ectopic endometriosis in the benign ovary. In addition, a 45-year-old POLE1-mutated ovarian endometrioid carcinoma patient was also diagnosed with uterine leiomyoma while the remaining 52-year-old POLE1-mutated patient showed no additional distinctive clinical manifestation. In contrast to high frequency of POLE1 mutations in ovarian endometrioid carcinoma, no POLE1 mutations were identified in patients with other subtypes of ovarian carcinoma. Our results showed for the first time that the POLE1 p.S297F mutation, but not p.P286R and p.V411L hotspot mutations observed in other cancer types, was frequent in Chinese ovarian endometrioid carcinoma, but absent in other subtypes of ovarian carcinoma. These results implicated that POLE1 p.S297F mutation might be actively involved in the pathogenesis of ovarian endometrioid carcinoma, but might not be actively involved in other subtypes of ovarian carcinoma.


Assuntos
Povo Asiático/genética , Carcinoma Endometrioide/genética , DNA Polimerase II/genética , Neoplasias do Endométrio/genética , Mutação , Neoplasias Epiteliais e Glandulares/genética , Neoplasias Ovarianas/genética , Adolescente , Adulto , Idoso , Sequência de Aminoácidos , Carcinoma Epitelial do Ovário , Criança , Pré-Escolar , Feminino , Heterozigoto , Humanos , Pessoa de Meia-Idade , Dados de Sequência Molecular , Proteínas de Ligação a Poli-ADP-Ribose , Alinhamento de Sequência , Adulto Jovem
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