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1.
Lab Invest ; 101(9): 1142-1152, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34103662

RESUMO

Numerous studies have revealed that hyperglycemia is a pivotal driver of diabetic vascular complications. However, the mechanisms of hyperglycemia-induced endothelial dysfunction in diabetes remain incompletely understood. This study aims to expound on the underlying mechanism of the endothelial dysfunction induced by hyperglycemia from the perspective of long non-coding RNAs (lncRNA). In this study, a downregulation of SNHG15 was observed in the ischemic hind limb of diabetic mice and high glucose (HG)-treated HUVECs. Functionally, the overexpression of SNHG15 promoted cell proliferation, migration, and tube formation, and suppressed cell apoptosis in HG-treated HUVECs. Mechanistically, SNHG15 reduced thioredoxin-interacting protein (TXNIP) expression by enhancing ITCH-mediated ubiquitination of TXNIP. TXNIP overexpression abrogated the protective effect of lncRNA SNHG15 overexpression on HG-induced endothelial dysfunction. The following experiment further confirmed that SNHG15 overexpression promoted angiogenesis of the ischemic hind limb in diabetic mice. In conclusion, SNHG15 is a novel protector for hyperglycemia-induced endothelial dysfunction via decreasing TXNIP expression.


Assuntos
Proteínas de Transporte , Hiperglicemia/metabolismo , RNA Longo não Codificante , Tiorredoxinas , Ubiquitinação/genética , Animais , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Células Cultivadas , Diabetes Mellitus Experimental/metabolismo , Células Endoteliais/citologia , Células Endoteliais da Veia Umbilical Humana , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Tiorredoxinas/genética , Tiorredoxinas/metabolismo
2.
J Endovasc Ther ; 28(1): 44-52, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32748684

RESUMO

Purpose: To report the findings of an in vitro experiment to evaluate the quality of needle fenestrations dilated by different size balloons in various stent-grafts and to investigate the differences between gradual and rapid dilation. Materials and Methods: Fenestrations were made using an 18-G needle in 5 different polyester or expanded polytetrafluoroethylene (ePTFE) stent-grafts: Relay, Valiant, Hercules, TAG, and Ankura. Each stent-graft received 2 groups of fenestrations: one was followed by gradual sequential dilation (4-, 6-, 8-, and 10-mm balloons) and the other by rapid dilation (4- and 10-mm balloons). The pressure was increased to 10 atmospheres or until the balloon was fully inflated with no waist. Quantitative and qualitative evaluations, including fenestration diameter, area, shape, and margins were conducted using light microscopy and scanning electron microscopy. Results: Relay had the strongest resistance to dilation and Ankura the slightest. The maximum length and area of holes expanded as the balloon diameter increased. The fenestrations in polyester devices were mostly elliptical or slit-like, with limited tears but extensive fibers visible in the margin, while ePTFE stent-grafts showed larger fenestration areas with clearer margins. Ankura showed the best quality of fenestrations, which were always circular or square without fabric tears, while the holes in the TAG were square or elliptical but sometimes had a slit after large balloon dilation (≥6 mm). The Relay, Valiant, Hercules, and Ankura devices showed no difference in maximum diameter, fenestration area, or scores of shape and margin (p>0.05). Rapid dilation in the TAG increased the rate of uncontrolled fabric tear, resulting in a larger final diameter (12.90 vs 10.82 mm, p=0.047), smaller area (30.46 vs 41.09 mm2, p=0.028), worse shape (0.75 vs 1.20, p=0.268), and worse margin (0.40 vs 1.00, p=0.174). Though the decreased fenestration shape and margin scores did not reach statistical significance, the trend for decline was more obvious than with the other devices. Conclusion: Materials and structures of the stent-grafts determine the quality of fenestrations dilated by different size balloons. The use of sequential vs rapid balloon dilation is also crucial for fashioning high-quality fenestrations and should be selected judiciously.


Assuntos
Stents , Prótese Vascular , Implante de Prótese Vascular/efeitos adversos , Dilatação , Humanos , Teste de Materiais , Desenho de Prótese , Resultado do Tratamento
3.
J Endovasc Ther ; 27(3): 358-367, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32166999

RESUMO

Purpose: To compare characteristics of acute, subacute, and chronic type B aortic dissection and their influence on long-term results of thoracic endovascular aortic repair (TEVAR). Materials and Methods: In a single-center, retrospective cohort study, 314 patients (median age 52 years; 244 men) with acute (n=165), subacute (n=115), or chronic (n=34) type B aortic dissection underwent TEVAR between January 2009 and December 2013. Patient demographics, risk factors, and imaging characteristics were compared among the groups. Univariable and multivariable Cox regression analyses were performed to identify any factors influencing survival. Results: The acute and subacute patients exhibited more complications at presentation than chronic patients. However, the chronic patients exhibited more aneurysmal dilatation (p<0.001) and true lumen collapse (p<0.001). Over a mean follow-up of 68.1±22.9 months (range 2-108), subacute patients showed a lower reintervention rate (3.6% vs 12.1% vs 12.1%, p=0.045), a lower major complication rate (14.4% vs 33.1% vs 27.3%, p=0.002), and better cumulative overall survival (p=0.03) than the acute and chronic groups, respectively. Furthermore, acute patients developed more stent-graft-induced distal erosion (p=0.017) and retrograde type A dissection (RTAD) (p=0.036), whereas chronic patients had less aortic remodeling in the stented segment (p<0.001), distal thoracic aorta (p<0.001), and abdominal aorta (p=0.047). Finally, multivariable analysis demonstrated age >52 years, visceral malperfusion, and RTAD as independent factors influencing overall survival; aneurysmal dilatation, rupture/impending rupture, and RTAD were independent factors influencing aorta-specific survival. Conclusion: Acute and subacute patients had increased risks of rupture and complications at presentation, whereas chronic patients had increased risks for aneurysmal dilatation. From a long-term perspective, the subacute phase might be an optimal time for TEVAR in cases of type B aortic dissection that do not need emergent interventions. The risk factors influencing survival should be identified, carefully managed, and possibly prevented.


Assuntos
Aneurisma da Aorta Abdominal/cirurgia , Aneurisma da Aorta Torácica/cirurgia , Dissecção Aórtica/cirurgia , Implante de Prótese Vascular , Procedimentos Endovasculares , Doença Aguda , Adulto , Idoso , Idoso de 80 Anos ou mais , Dissecção Aórtica/diagnóstico por imagem , Dissecção Aórtica/mortalidade , Dissecção Aórtica/fisiopatologia , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Aneurisma da Aorta Abdominal/mortalidade , Aneurisma da Aorta Abdominal/fisiopatologia , Aneurisma da Aorta Torácica/diagnóstico por imagem , Aneurisma da Aorta Torácica/mortalidade , Aneurisma da Aorta Torácica/fisiopatologia , Implante de Prótese Vascular/efeitos adversos , Implante de Prótese Vascular/instrumentação , Implante de Prótese Vascular/mortalidade , Doença Crônica , Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/instrumentação , Procedimentos Endovasculares/mortalidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Remodelação Vascular
4.
Eur J Vasc Endovasc Surg ; 55(3): 369-376, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29306627

RESUMO

OBJECTIVES: Endovascular repair of aortic arch pathologies remains challenging. Recently, needle based in situ fenestration (ISF) has shown great potential in endovascular total aortic arch repair (ETAAR). This study aimed to evaluate the feasibility, effectiveness, and safety of ETAAR via needle based ISF, and to present initial experience with this technique. DESIGN AND METHODS: Patients who met the inclusion criteria were enrolled in this prospective study. The supra-arch branches were manually punctured in a retrograde manner using liver biopsy needles (18 gauge/30 cm) in the left common carotid artery (LCCA) and brachiocephalic trunk (BCT), and endo-puncture system or aspiration biopsy needles (21-gauge) in the left subclavian artery (LSA). All the branches were revascularised with bridge stents. Routine follow-up occurred at 1, 3, 6, and 12 months post surgery. RESULTS: Ten patients with arch pathologies underwent ETAAR. Revascularisation of three branches was successfully performed in eight patients, but attempts to create ISF in LSA were unsuccessful in two patients because of tortuosity and sharp angle. The time taken to establish ISF in LCCA and BCT was 100.4s and 489.6s, respectively. Bilateral regional cerebral oxygen saturation (RCOS) decreased after the arch endograft deployment (both, p < .001) and recovered to the pre-operative level once both carotid arteries were reconstructed (left, p = .0856; right, p = .6). The right RCOS was higher with the beneficial effect of extracorporeal circulation (after cTAGs deployment, p < .001; after LCCA revascularised, p = .0148) during the ischaemic period. In one case, the left iliac artery ruptured, but no ISF related or neurological complications occurred. An early follow-up (mean 5.44 months) CTA and ultrasound confirmed patency of all the branch grafts without any endoleak or migration CONCLUSIONS: This study demonstrated that ETAAR via needle based ISF, making full use of off the shelf devices and techniques, can be successfully performed in aortic arch pathologies with a favourable early outcome.


Assuntos
Aorta Torácica/cirurgia , Doenças da Aorta/cirurgia , Implante de Prótese Vascular/instrumentação , Prótese Vascular , Procedimentos Endovasculares/instrumentação , Stents , Adulto , Idoso , Aorta Torácica/diagnóstico por imagem , Aorta Torácica/fisiopatologia , Doenças da Aorta/diagnóstico por imagem , Doenças da Aorta/fisiopatologia , Aortografia/métodos , Implante de Prótese Vascular/efeitos adversos , Tronco Braquiocefálico/cirurgia , Artéria Carótida Primitiva/cirurgia , Circulação Cerebrovascular , Angiografia por Tomografia Computadorizada , Procedimentos Endovasculares/efeitos adversos , Circulação Extracorpórea , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Agulhas , Estudos Prospectivos , Desenho de Prótese , Artéria Subclávia/cirurgia , Fatores de Tempo , Resultado do Tratamento , Grau de Desobstrução Vascular
5.
J Vasc Res ; 54(4): 226-234, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28723696

RESUMO

Advanced glycation end-products (AGEs) have been recognized as an important pathophysiological mechanism in endothelial dysfunction during diabetic atherogenesis. Homeobox (Hox) genes have been identified as playing a regulatory role in the adult cardiovascular system. Regulation of HoxA9EC is involved in diabetic endothelial dysfunction, but the mechanism of HoxA9EC regulation has remained undefined. Here, we sought to investigate how HoxA9EC is regulated in AGE-induced endothelial dysfunction and to explore the mechanism involved. We used human umbilical venous endothelial cells (HUVECs) cocultured with AGEs, and examined endothelial nitric oxide synthase (eNOS) activation, nitric oxide (NO) release, cell migration, and the expression of HoxA9EC and nuclear factor kappa B (NF-κB). AGEs suppressed eNOS activation, NO release, and the migration of HUVECs. Knockout of HoxA9EC also reduced eNOS activation, NO release, and the migration of HUVECs, and the enhancement of HoxA9EC improved the function of HUVECs. Furthermore, AGEs downregulated HoxA9EC expression and activated NF-κB, and the depression of HoxA9EC was significantly attenuated by the NF-κB inhibitor. On the other hand, knockout of HoxA9EC activated NF-κB and the enhancement of HoxA9EC suppressed NF-κB activation. In conclusion, AGEs could induce endothelial dysfunction through NF-κB-dependent HoxA9EC downregulation by reciprocal interaction, and the enhancement of HoxA9EC expression could attenuate the impairment.


Assuntos
Produtos Finais de Glicação Avançada/farmacologia , Proteínas de Homeodomínio/metabolismo , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , NF-kappa B/metabolismo , Movimento Celular/efeitos dos fármacos , Células Cultivadas , Regulação para Baixo , Proteínas de Homeodomínio/genética , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Interferência de RNA , Transdução de Sinais/efeitos dos fármacos , Transfecção
6.
J Vasc Surg ; 64(2): 389-394, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26926933

RESUMO

OBJECTIVE: We report the morphologic findings and treatment of spontaneous isolated dissection of the celiac artery (SIDCA). METHODS: Twenty-three patients with SIDCA presenting between January 2009 and December 2014 were enrolled in this retrospective study. The demographic data, clinical features, morphologic findings, treatment modalities, and follow-up results of these patients were reviewed. We proposed a morphologic classification for SIDCA similar to that of spontaneous isolated dissection of the superior mesenteric artery. RESULTS: Initially, 11 patients were treated endovascularly, and 12 were treated medically. Four patients treated medically had an aggravation of the dissection and needed endovascular salvage. All patients recovered successfully. None of the patients developed abdominal pain, required reintervention, or died. In the medically treated group, the false lumen was completely thrombosed and absorbed in 4 patients, partially thrombosed in 2, and patent in 2. All stents were patent with the false lumen completely thrombosed and absorbed in the endovascular group. CONCLUSIONS: SIDCA can be treated medically in stable patients but requires intensive follow-up. Endovascular therapy can be applied in high-risk patients with recurrent symptoms, visceral malperfusion, or aneurysm. Open surgery should be considered if endovascular repair is not suitable or has failed. The short-term results of endovascular management are encouraging but further evaluation with long-term follow-up is necessary.


Assuntos
Dissecção Aórtica/diagnóstico por imagem , Dissecção Aórtica/terapia , Fármacos Cardiovasculares/uso terapêutico , Artéria Celíaca/diagnóstico por imagem , Angiografia por Tomografia Computadorizada/métodos , Embolização Terapêutica , Procedimentos Endovasculares , Tomografia Computadorizada Espiral , Adulto , Idoso , Idoso de 80 Anos ou mais , Dissecção Aórtica/fisiopatologia , Artéria Celíaca/fisiopatologia , Procedimentos Endovasculares/instrumentação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Fluxo Sanguíneo Regional , Estudos Retrospectivos , Terapia de Salvação , Stents , Fatores de Tempo , Resultado do Tratamento , Grau de Desobstrução Vascular
7.
J Vasc Surg ; 61(6): 1424-31, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25702918

RESUMO

OBJECTIVE: We report our experience of endovascular management and postoperative aortic remodeling of all types of isolated abdominal aortic dissection (IAAD). METHODS: This was retrospective study of 28 IAAD patients treated by endovascular means in our department between January 2007 and July 2013. We reviewed the risk factors, clinical features, computed tomography images, follow-up results, and aortic remodeling of these IAAD patients and propose a new morphologic classification into three types-supraceliac, paravisceral, and infrarenal-according to the location of the primary entry site. RESULTS: There were four supraceliac IAADs, one paravisceral IAAD, and 23 infrarenal IAADs in our case series. Suprarenal (supraceliac + paravisceral) IAAD patients were relatively younger than infrarenal patients (45.2 ± 8.6 years vs 60.6 ± 15.5 years; P < .05). No difference was observed between suprarenal and infrarenal IAADs with respect to true lumen, false lumen, and dissection length on imaging (P > .05). All patients received endovascular treatment. The primary technical success rate was 100%. During a follow-up of 35.7 ± 19.9 months, only one infrarenal patient needed an endovascular reintervention. All patients with supraceliac or infrarenal IAADs were alive at the time of follow-up; however, a paravisceral patient died of a dissecting abdominal aortic aneurysm rupture 21 months after endovascular treatment. In the suprarenal and infrarenal groups, endovascular treatment was associated with a significant decrease in the false lumen size and increase in the true lumen size (P < .05). The maximum abdominal aorta diameter decreased after endovascular treatment in both groups but was statistically significant only in the infrarenal group (P < .05). CONCLUSIONS: IAAD is a rare vascular disease. We propose it should be categorized as supraceliac, paravisceral, and infrarenal IAAD according to the location of the primary entry site. Endovascular treatment for supraceliac and infrarenal IAADs is a safe method with a high technical success rate and promising aortic remodeling, whereas endovascular treatment for paravisceral IAADs remains difficult.


Assuntos
Aneurisma da Aorta Abdominal/cirurgia , Dissecção Aórtica/cirurgia , Implante de Prótese Vascular , Procedimentos Endovasculares , Remodelação Vascular , Adulto , Idoso , Dissecção Aórtica/diagnóstico , Dissecção Aórtica/mortalidade , Dissecção Aórtica/fisiopatologia , Aneurisma da Aorta Abdominal/diagnóstico , Aneurisma da Aorta Abdominal/mortalidade , Aneurisma da Aorta Abdominal/fisiopatologia , Aortografia/métodos , Implante de Prótese Vascular/efeitos adversos , Implante de Prótese Vascular/mortalidade , China , Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/mortalidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Tomografia Computadorizada por Raios X , Resultado do Tratamento
8.
Chaos ; 25(8): 083110, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26328561

RESUMO

We construct a two-parameter family of moon-shaped billiard tables with boundary made of two circular arcs. These tables fail the defocusing mechanism and other known mechanisms that guarantee ergodicity and hyperbolicity. We analytically study the stability of some periodic orbits and prove there is a class of billiards in this family with elliptic periodic orbits. These moon billiards can be viewed as generalization of annular billiards, which all have Kolmogorov-Arnold-Moser islands. However, the novelty of this paper is that by varying the parameters, we numerically observe a subclass of moon-shaped billiards with a single ergodic component.

9.
J Vasc Surg ; 59(1): 165-72, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23992995

RESUMO

OBJECTIVE: To explore a therapy strategy for the spontaneous isolated dissection of the superior mesenteric artery (SIDSMA) based on morphologic classification. METHODS: Forty-two symptomatic patients with SIDSMA presenting with abdominal pain between January 2007 and December 2012 were enrolled in this retrospective study. We proposed a new morphologic classification with subtypes depending on the patency of the true lumen and reviewed the patients' clinical features, risk factors, computed tomography images (morphologic classification, location of entry site, dissection length, and true lumen residual diameter), treatment modalities, and follow-up results. RESULTS: Twenty-four patients received only observation treatment, seven received open surgery, and 11 received endovascular therapy. True lumen residual diameter in the observation group (46.6%) was statistically better than that in the surgery group (0%) and the endovascular group (18.3%) (P < .05). There was clinical progression in three and imaging progression in seven of the observation group, of which two patients received endovascular treatment and one patient died of bowel infarction. There were two clinical progressions and one imaging progression in the surgery group, of which two patients received additional surgery and one patient died of bowel infarction. The endovascular group obtained encouraging results with no progressions or complications. CONCLUSIONS: Symptomatic patients with SIDSMA are at risk of progression. We suggested a morphologic classification to guide the treatment. We recommend observation treatment with close follow-up for patients with patent true lumen flow and endovascular intervention for high-risk patients with true lumen stenosis or occlusion. Surgery is indicated for patients with suspected bowel infarction or arterial rupture.


Assuntos
Dissecção Aórtica/classificação , Dissecção Aórtica/terapia , Procedimentos Endovasculares , Artéria Mesentérica Superior/cirurgia , Procedimentos Cirúrgicos Vasculares , Conduta Expectante , Dor Abdominal/etiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Dissecção Aórtica/complicações , Dissecção Aórtica/diagnóstico por imagem , Dissecção Aórtica/mortalidade , Dissecção Aórtica/cirurgia , Distribuição de Qui-Quadrado , Progressão da Doença , Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/mortalidade , Feminino , Humanos , Masculino , Artéria Mesentérica Superior/diagnóstico por imagem , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Procedimentos Cirúrgicos Vasculares/efeitos adversos , Procedimentos Cirúrgicos Vasculares/mortalidade
10.
Neural Netw ; 173: 106152, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38359640

RESUMO

We introduce the Discrete-Temporal Sobolev Network (DTSN), a neural network loss function that assists dynamical system forecasting by minimizing variational differences between the network output and the training data via a temporal Sobolev norm. This approach is entirely data-driven, architecture agnostic, and does not require derivative information from the estimated system. The DTSN is particularly well suited to chaotic dynamical systems as it minimizes noise in the network output which is crucial for such sensitive systems. For our test cases we consider discrete approximations of the Lorenz-63 system and the Chua circuit. For the network architectures we use the Long Short-Term Memory (LSTM) and the Transformer. The performance of the DTSN is compared with the standard MSE loss for both architectures, as well as with the Physics Informed Neural Network (PINN) loss for the LSTM. The DTSN loss is shown to substantially improve accuracy for both architectures, while requiring less information than the PINN and without noticeably increasing computational time, thereby demonstrating its potential to improve neural network forecasting of dynamical systems.


Assuntos
Algoritmos , Redes Neurais de Computação , Aprendizagem , Memória de Longo Prazo , Previsões
11.
Chaos ; 23(4): 043137, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24387576

RESUMO

In this paper, we study a two-parameter family of convex billiard tables, by taking the intersection of two round disks (with different radii) in the plane. These tables give a generalization of the one-parameter family of lemon-shaped billiards. Initially, there is only one ergodic table among all lemon tables. In our generalized family, we observe numerically the prevalence of ergodicity among the some perturbations of that table. Moreover, numerical estimates of the mixing rate of the billiard dynamics on some ergodic tables are also provided.

12.
Phys Rev E ; 107(3-1): 034217, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37072957

RESUMO

In the present work we explore the concept of solitary wave billiards. That is, instead of a point particle, we examine a solitary wave in an enclosed region and examine its collision with the boundaries and the resulting trajectories in cases which for particle billiards are known to be integrable and for cases that are known to be chaotic. A principal conclusion is that solitary wave billiards are generically found to be chaotic even in cases where the classical particle billiards are integrable. However, the degree of resulting chaoticity depends on the particle speed and on the properties of the potential. Furthermore, the nature of the scattering of the deformable solitary wave particle is elucidated on the basis of a negative Goos-Hänchen effect which, in addition to a trajectory shift, also results in an effective shrinkage of the billiard domain.

13.
Phys Rev E ; 108(2): L022301, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37723734

RESUMO

We introduce a methodology for seeking conservation laws within a Hamiltonian dynamical system, which we term "neural deflation." Inspired by deflation methods for steady states of dynamical systems, we propose to iteratively train a number of neural networks to minimize a regularized loss function accounting for the necessity of conserved quantities to be in involution and enforcing functional independence thereof consistently in the infinite-sample limit. The method is applied to a series of integrable and nonintegrable lattice differential-difference equations. In the former, the predicted number of conservation laws extensively grows with the number of degrees of freedom, while for the latter, it generically stops at a threshold related to the number of conserved quantities in the system. This data-driven tool could prove valuable in assessing a model's conserved quantities and its potential integrability.

14.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 6): m856, 2012 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-22719389

RESUMO

In the title compound, [Cd(NO(3))(2)(C(12)H(12)N(6))(2)](n), the Cd(II) cation is located on an inversion center and is six-coordinated by four N atoms from four 1,3-bis-[(1H-1,2,4-triazol-1-yl)meth-yl]benzene (L) ligands and two O atoms from two nitrate anions in a slightly distorted octa-hedral geometry. The ligands link different Cd(II) ions into a ribbon-like structure along [001]. Two O atoms of the nitrate anion are disordered over two sets of sites with site occupancies of 0.575 (8) and 0.425 (8).

15.
Viruses ; 14(11)2022 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-36366562

RESUMO

Many approaches using compartmental models have been used to study the COVID-19 pandemic, with machine learning methods applied to these models having particularly notable success. We consider the Susceptible-Infected-Confirmed-Recovered-Deceased (SICRD) compartmental model, with the goal of estimating the unknown infected compartment I, and several unknown parameters. We apply a variation of a "Physics Informed Neural Network" (PINN), which uses knowledge of the system to aid learning. First, we ensure estimation is possible by verifying the model's identifiability. Then, we propose a wavelet transform to process data for the network training. Finally, our central result is a novel modification of the PINN's loss function to reduce the number of simultaneously considered unknowns. We find that our modified network is capable of stable, efficient, and accurate estimation, while the unmodified network consistently yields incorrect values. The modified network is also shown to be efficient enough to be applied to a model with time-varying parameters. We present an application of our model results for ranking states by their estimated relative testing efficiency. Our findings suggest the effectiveness of our modified PINN network, especially in the case of multiple unknown variables.


Assuntos
COVID-19 , Humanos , COVID-19/epidemiologia , Pandemias , Modelos Epidemiológicos , Redes Neurais de Computação , Física
16.
Phlebology ; 37(8): 572-578, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35570826

RESUMO

OBJECTIVES: Leiomyosarcoma of the inferior vena cava (IVC) is rare. The study reviewed patients with IVC leiomyosarcoma in our hospital in the past ten years. METHODS: Twenty patients diagnosed with IVC leiomyosarcoma between October 2010 and October 2020 were enrolled. Their clinical manifestations, treatments, and follow-up results were analyzed. RESULTS: The sarcoma was located in the lower IVC segment in six patients, with 13 in the middle and one in the upper IVC segment. Eighteen patients underwent R0 resection. After resection, 16 patients (80%) had primary repair of the IVC, while four patients underwent ligation. During a mean follow-up of 37.7 months, seven patients died due to tumor metastasis, four patients were alive with the tumor recurrence and other nine patients were alive without recurrence. CONCLUSION: The management of the IVC after tumor resection depended on the tumor location and size. R0 resection provided a chance for long term survival.


Assuntos
Leiomiossarcoma , Neoplasias Vasculares , Humanos , Leiomiossarcoma/diagnóstico por imagem , Leiomiossarcoma/patologia , Leiomiossarcoma/cirurgia , Ligadura , Estudos Retrospectivos , Resultado do Tratamento , Neoplasias Vasculares/patologia , Neoplasias Vasculares/cirurgia , Veia Cava Inferior/cirurgia
17.
J Agric Food Chem ; 69(11): 3452-3465, 2021 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-33724017

RESUMO

An efficient technique using citric acid and glucose based natural deep eutectic solvent (G-C-NADES) was developed to obtain ultrahigh deamidated wheat gluten (UDWG) (deamidation degree (DD) > 90%). FTIR and 1H NMR indicated intensive hydrogen bonds (HBs) in G-C-NADES supermolecules. Quantum chemical calculations and molecular dynamic simulations demonstrated that 10 wt % diluted G-C-NADES still had a myriad of HBs. Physicochemical results showed UDWG had DD up to 92.45% after G-C-NADES deamidation, that is, 22% higher than citric-acid-DWG with a weak degree of hydrolysis (1.75%). Conformational characterization demonstrated the obvious conversion from α-helix to ß-sheet via FTIR, the least amount of disulfide bonds by Raman spectra, and more exposure of tryptophan residues by fluorescence measurement for UDWG. It is proven that enhanced accessible conformation of WG reached with HBs of G-C-NADESs could contribute to the improvement on nucleophilic attack of deamidation, declaring that G-C-NADES might be a potential solvent for obtaining an ultrahigh deamidation for WG to successfully guarantee the safety of wheat gluten based cereal food regarding to lowering its allergy.


Assuntos
Ácido Cítrico , Triticum , Glucose , Glutens , Solventes
18.
Cell Cycle ; 20(14): 1389-1401, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34223793

RESUMO

Vascular endothelial dysfunction is associated with the progress of many diseases. Circular RNAs (circRNAs) take part in the dysfunction of vascular endothelium. CircRNA hsa_circ_0008360 (circ_0008360) is dysregulated in high glucose-treated vascular endothelium, while the role and mechanism of circ_0008360 in high glucose-induced dysfunction remain unknown. Human umbilical vascular endothelium cells (HUVEC) were stimulated via high glucose. The abundances of circ_0008360, miR-186-5p and cyclin D2 (CCND2) were examined via quantitative real-time polymerase chain reaction or western blot. Vascular endothelial dysfunction was assessed via cell viability, apoptosis, migration and tube formation. The target relationship between miR-186-5p and circ_0008360 or CCND2 was analyzed via dual-luciferase reporter, RNA pull-down and RNA immunoprecipitation analyses. Circ_0008360 expression was enhanced in high-glucose-treated HUVEC. Circ_0008360 silence mitigated high glucose-induced suppression of viability, migration, tube formation, and increase in apoptosis in HUVEC. MiR-186-5p was sponged by circ_0008360, and miR-186-5p inhibition reversed the effect of circ_0008360 silence on high glucose-induced vascular endothelial dysfunction. MiR-186-5p alleviated high glucose-induced vascular endothelial dysfunction via targeting CCND2. CCND2 interference abolished the aggravated effect of circ_0008360 on high glucose-induced vascular endothelial dysfunction. Circ_0008360 knockdown attenuated high glucose-induced vascular endothelial dysfunction via regulating miR-186-5p and CCND2, indicating circ_0008360 might act as a target for the treatment of vascular endothelial dysfunction.Abbreviations: circRNAs, circular RNAs; HUVEC, human umbilical vascular endothelium cells; CCND2, cyclin D2; XPNPEP3, X-prolyl aminopeptidase 3; ceRNAs, competing endogenous RNAs; miRNAs, microRNAs; qRT-PCR, quantitative real-time polymerase chain reaction; RIP, RNA immunoprecipitation; HIF-1α, hypoxia inducible factor 1 alpha; TLR3, toll-like receptor 3; AKAP12, A-Kinase Anchoring Protein 12; ox-LDL, oxidized low-density lipoprotein; HG, high glucose; NG, normal glucose.


Assuntos
MicroRNAs , RNA Circular , Apoptose/genética , Proliferação de Células/genética , Ciclina D2/genética , Glucose/farmacologia , Humanos , MicroRNAs/metabolismo , RNA Circular/genética
19.
Life Sci ; : 119255, 2021 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-33636173

RESUMO

OBJECTIVE: Numerous evidence indicates that hyperglycemia is a pivotal driver of the vascular complications of diabetes. However, the mechanisms of hyperglycemia-induced endothelial dysfunction in diabetes remain incompletely understood. This study aims to expound on the underlying mechanism of the endothelial dysfunction induced by hyperglycemia from the perspective of long non-coding RNAs (lncRNA). MATERIALS AND METHODS: Cell proliferation, migration, apoptosis, and tube formation were measured by cell counting kit-8 assay, transwell assay, flow cytometry, and tube formation assay, respectively. RNA pull-down and RNA-binding protein immunoprecipitation were used to detect the interaction between lncRNA SNHG15 and thioredoxin-interacting protein (TXNIP). Co-immunoprecipitation was used to detect the ubiquitination level of TXNIP and the interaction between TXNIP and E3 ubiquitin ligase ITCH. RESULTS: A downregulation of SNHG15 was observed in the ischemic hind limb of diabetic mice and high glucose (HG)-treated HUVECs. Functionally, the overexpression of SNHG15 promoted cell proliferation, migration, and tube formation, and suppressed cell apoptosis in HG-treated HUVECs. Mechanically, SNHG15 reduced TXNIP expression by enhancing ITCH-mediated ubiquitination of TXNIP. TXNIP overexpression abrogated the protective effect of LncRNA SNHG15 overexpression on HG-induced endothelial dysfunction. The following experiment further confirmed that SNHG15 overexpression promoted angiogenesis of the ischemic hind limb in diabetic mice. CONCLUSION: SNHG15 is a novel protector for hyperglycemia-induced endothelial dysfunction via decreasing TXNIP expression.

20.
J Endovasc Ther ; 17(5): 617-21, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20939719

RESUMO

PURPOSE: To report a prospective study that explored the therapeutic strategies in the treatment of type B aortic intramural hematoma (IMH) and evaluated the role of endovascular repair. METHODS: Between January 2001 and December 2009, 56 consecutive patients were enrolled in a prospective study to evaluate stent-graft repair versus medical therapy for acute type B IMH (patients with type A IMH excluded). Patients who had penetrating atherosclerotic ulcers, maximum aortic diameter >45 mm, hematoma thickness >10 mm, or sustained chest or back pain despite maximal medical therapy received endovascular stent-grafts (n=33; mean age 60 years, range 33-86), while other patients (n=23; mean age 56 years, range 29-83) received conservative therapy. RESULTS: Stent-grafts were implanted successfully as scheduled in 33 patients as elective procedures; there were no complications related to the procedure. The mean follow-up up was 28±15 months (range 3-108). In the medically treated patients, there were 6 (26%) cases of IMH progression (4 treated with stent-grafts) and 2 (9%) deaths versus no IMH progression or death in the stent-graft patients. The thickness of the hematoma was reduced in all 37 patients receiving stent-grafts, and the maximum aortic diameter decreased in 19 of these patients. The 17 surviving patients in the medical group also showed regression of the hematoma in follow-up. CONCLUSION: Type B IMH is a potentially lethal disease, and the application of endovascular stent-grafts achieved an encouraging result in this study. Therefore, a more optimistic strategy, including endovascular repair, should be considered and evaluated in the future.


Assuntos
Doenças da Aorta/cirurgia , Implante de Prótese Vascular , Procedimentos Endovasculares , Hematoma/cirurgia , Doença Aguda , Adulto , Idoso , Idoso de 80 Anos ou mais , Analgésicos/uso terapêutico , Anti-Hipertensivos/uso terapêutico , Doenças da Aorta/diagnóstico , Doenças da Aorta/tratamento farmacológico , Doenças da Aorta/mortalidade , Prótese Vascular , Implante de Prótese Vascular/efeitos adversos , Implante de Prótese Vascular/instrumentação , China , Procedimentos Cirúrgicos Eletivos , Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/instrumentação , Feminino , Hematoma/diagnóstico , Hematoma/tratamento farmacológico , Hematoma/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Stents , Fatores de Tempo , Resultado do Tratamento
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