Volumetric analysis of effectiveness of embolization for preventing type II endoleaks following endovascular aortic aneurysm repair.

OBJECTIVE: The presence of endoleak was associated with the failure of endovascular aortic aneurysm repair (EVAR) treatment. The key to eliminating type II endoleak has shifted from reintervention to prevention. This study aimed to evaluate the effectiveness and safety of applying fibrin sealant to prevent type II endoleak in conjunction with EVAR. METHODS: All patients with abdominal aortic aneurysm who underwent EVAR from June 2019 to July 2021 were reviewed. Patients were grouped as Group A: standard EVAR with preemptive embolization and Group B: standard EVAR alone. The primary endpoint was the incidence of type II endoleak. The secondary endpoints were aneurysm sac regression, the inferior mesenteric artery patency, the numbers of patent lumbar arteries, and all-cause mortality. RESULTS: A total of 104 patients were included in Group A, and 116 were included in Group B. Technical success rate was 100%. The overall incidence of type II endoleak in Group A was significantly lower than that in Group B (4.8% vs 19.0%). The mean time of freedom from type II endoleak was 22.71 months for Group A (95% confidence interval, 21.59-23.83 months) and 19.89 months for Group B (95% confidence interval, 18.08-21.70 months). The Kaplan-Meier estimate of freedom from type II endoleak showed a significantly longer duration of freedom from type II endoleak in Group A (81.0% vs 95.2%). Group A showed a continuous sac regression tendency. In Group B, the sac volume decreased within 12 months but increased by 3.07 cm3 at 24 months. No complications were noted in both groups. CONCLUSIONS: Nonselective preemptive embolization with porcine fibrin sealant during EVAR was safe and effective in preventing type II endoleak in the short and mid-term. Preemptive embolization can lead to a significantly higher sac regression rate. Larger patient populations and longer follow-ups with randomized control designed trials are expected to verify the long-term effectiveness and safety of preemptive embolization in preventing type II endoleak.

Successful Endovascular Repair in a Patient with Isolated Proximal Subclavian Artery Dissecting Aneurysm: Case Report and Literature Review.

Spontaneous isolated subclavian artery dissecting aneurysm is rare. This is to our knowledge the first case in the world's literature to report a patient with subclavian artery dissecting aneurysm. Although the endovascular approach of treating subclavian artery pathologies is not challenging, the choice of using a covered stent for this patient was a new attempt in treating subclavian artery dissections. This case report highlights the possibility and safety of using covered stent in treating patients with subclavian artery dissecting aneurysms after reassuring the patency of the cerebral circulation system.

Complete Endovascular Repair for Abdominal Aortic Aneurysm With Concomitant Aorto-Left Retroaortic Renal Vein Fistula.

BACKGROUND: Abdominal aortic aneurysm (AAA) with concomitant aorto-retroarotic left renal vein fistula (ALRVF) is an extremely rare clinical condition. With the recent development of endovascular techniques, repair of such conditions with a complete minimal invasive approach is now possible. We reported here a case of endovascular repair of AAA with concomitant ALRVF. CASE PRESENTATION: A 62-year-old gentleman presenting with AAA and concomitant ALRVF underwent complete endovascular repair, including an endovascular aortic aneurysm repair (EVAR) with bifurcated aortic graft as well as embolization of the aneurysm sac and deployment of a covered stent in the left retroarotic renal vein to achieve sealing of the arterial-venous fistula. The patient required no blood transfusion and no ICU stay. He has been followed up closely for 4 years and has been well clinically. Aneurysm sac size has remained stable. CONCLUSIONS: Endovascular repair can be a safe and reliable surgical alternative to treat AAA with concomitant ALRVF. But long-term follow up and more clinical data are required to verify the durability of endovascular repair for such conditions.

[The treatment strategy of special distal landing zones in endovascular repair of abdominal aortic aneurysm].

OBJECTIVE: To study the assessment and management for abdominal aortic aneurysm (AAA)'s special distal landing zones in endovascular repair (EVAR). METHODS: The clinic data of 66 AAA patients with complicated distal landing zones From January 2007 to December 2010 was retrospectively analyzed. There were 45 male and 21 female patients, aged from 53 to 87 years with a mean of 62 years. All patients underwent the CT angiography examination (1 to 2 mm interval) to obtain the necessary anatomical data. In this group, there were 20 cases with type I and IIA lesions, including 10 cases with narrow common iliac arteries/external iliac arteries (> 50%), 6 cases with seriously distorted common iliac arteries/external iliac arteries, 4 cases with the characters of the above, 16 cases with bilateral common iliac aneurysms, 46 cases with bilateral common iliac aneurysms combined internal iliac aneurysms (unilateral 32 cases, bilateral 14 cases). The vascular stent-grafts' usage was as follow: Metronic 46 cases, COOK 14 cases, Microport 4 cases, Lifetech 2 cases. RESULTS: The mean operative time was 90 min. There were significant stent-graft shortening in 22 cases (33.3%), type II endoleak in 18 cases (27.3%), type III endoleak in 5 cases (7.6%), iliac stents' stenosis (> 50%) in 2 cases (3.0%), type II combined with type III endoleak in 5 cases (7.6%), iliac stents' stenosis combined with type III endoleak in 4 cases (6.1%). Patients were followed for a mean of 22 months (range from 3 to 36 months), during the time of follow-up, the following conditions were observed: stent-graft displacement (to the remote < 10 mm) in 2 cases (3.0%), iliac stents restenosis (> 50%) 2 cases, type II endoleak healed in 18 cases (18/23, 78.3%), and no type III endoleak remained. The fatality rate was 3.0% (2/66). CONCLUSIONS: Special distal landing zones increased the operative complication rate in EVAR. Being familiar with the features of stent-graft and appropriate use of various surgical management can increase the success ratio of EVAR.

Full particle-in-cell simulation of the formation and structure of a collisional plasma shock wave.

The formation and structure of a collisional shock wave in a fully ionized plasma is studied via full particle-in-cell simulations, which allows the complex momentum and energy transfer processes between different charged particles to be treated self-consistently. The kinetic energy of the plasma flow drifting towards a reflecting piston is found to be rapidly converted into thermal motion under the cooperative effects of ion-ion collisions, ion-electron collisions, and electric field charged-particle interactions. The subsequent shock evolution is influenced by the "precursor" ion beam before a quasisteady state is reached. The shock wave structure is then analyzed from a two-fluid transport viewpoint, which is found to be affected by "flux-limiting" electron transport, the nonthermal ions, and the charge separation electric field.

Cyclic tensile strain facilitates proliferation and migration of human aortic smooth muscle cells and reduces their apoptosis via miRNA-187-3p.

The cardiovascular is a system that contains extremely complex mechanical factors, in which the circulatory flow of blood has rich mechanical laws. Many studies have revealed that mechanical factors play a very important role in the process of revascularization. Hence, it is essential to investigate the mechanical factors in the process of revascularization in depth. A cyclic tensile strain (CTS) was applied to human aortic smooth muscle cells (HASMCs) at a frequency of 1 Hz and amplitudes of 5%, 10% and 15%, respectively. SmallRNA-seq was used to identify differentially expressed miRNAs (DE-miRNAs) responding to CTS in HASMCs. Starbase database predicted the target genes of DE-miRNAs. Metascape was applied for GO and KEGG pathway enrichment analysis and protein-protein interaction network construction. The proliferation and migration of CTS-treated HASMCs were significantly enhanced, and apoptosis were significantly reduced compared to the control group. SmallRNA-seq results demonstrated that 55, 16 and 16 DE-miRNAs were present in 5%, 10% and 15% CTS-treated HASMCs, respectively. Compared to controls, with miR-26a-2-3p and miR-187-3p being the intersection of these DE-miRNAs. Starbase database identified 189 common target genes for miR-26a-2-3p and miR-187-3p. Common target genes are mainly enriched in the basolateral plasma membrane and endocytosis. Further, in vitro experiments exhibited that CTS upregulated miR-187-3p expression, and miR-187-3p enhanced the proliferation and migration of HASMCs and reduced their apoptosis. It is suggested that miR-187-3p may be an important target for CTS participate in the process of cardiovascular disease.[Figure: see text].

Generation of strong quasistatic magnetic fields in interactions of ultraintense and short laser pulses with overdense plasma targets.

An analytical fluid model is proposed for the generation of strong quasistatic magnetic fields during normal incidence of a short ultraintense Gaussian laser pulse with a finite spot size on an overdense plasma. The steepening of the electron density profile in the originally homogeneous overdense plasma and the formation of electron cavitation as the electrons are pushed inward by the laser are included self-consistently. It is shown that the appearance of the cavitation plays an important role in the generation of quasistatic magnetic fields: the strong plasma inhomogeneities caused by the formation of the electron cavitation lead to the generation of a strong axial quasistatic magnetic field Bz. In the overdense regime, the generated quasistatic magnetic field increases with increasing laser intensity, while it decreases with increasing plasma density. It is also found that, in a moderately overdense plasma, highly intense laser pulses can generate magnetic fields approximately 100 MG and greater due to the transverse linear mode conversion process.

Self-generated magnetic dipoles in weakly magnetized beam-plasma system.

A self-generation mechanism of magnetic dipoles and the anomalous energy dissipation of fast electrons in a magnetized beam-plasma system are presented. Based on two-dimensional particle-in-cell simulations, it is found that the magnetic dipoles are self-organized and play important roles in the beam electron energy dissipation. These dipoles drift slowly in the direction of the return flow with a quasisteady velocity, which depends upon the magnetic amplitude of the dipole and the imposed external magnetic field. This dipole formation provides a mechanism for the anomalous energy dissipation of a relativistic electron beam, which would play an important role in collisionless shock and ion shock acceleration.

Magnetic-field generation and electron-collimation analysis for propagating fast electron beams in overdense plasmas.

An analytical fluid model is proposed for artificially collimating fast electron beams produced in the interaction of ultraintense laser pulses with specially engineered low-density-core-high-density-cladding structure targets. Since this theory clearly predicts the characteristics of the spontaneously generated magnetic field and its dependence on the plasma parameters of the targets transporting fast electrons, it is of substantial relevance to the target design for fast ignition. The theory also reveals that the rapid changing of the flow velocity of the background electrons in a transverse direction (perpendicular to the flow velocity) caused by the density jump dominates the generation of a spontaneous interface magnetic field for these kinds of targets. It is found that the spontaneously generated magnetic field reaches as high as 100 MG, which is large enough to collimate fast electron transport in overdense plasmas. This theory is also supported by numerical simulations performed using a two-dimensional particle-in-cell code. It is found that the simulation results agree well with the theoretical analysis.

Enhancing the number of high-energy electrons deposited to a compressed pellet via double cones in fast ignition.

Particle-in-cell simulations aimed at improving the coupling efficiency of input laser energy deposited to a compressed core by using a double cone are described. It is found that the number of high-energy electrons escaping from the sides of the cone is greatly reduced by the vacuum gap inside the wing of the double cone. Two main mechanisms to confine high-energy electrons are found. These mechanisms are the sheath electric field at the rear of the inner cone wing and the quasistatic magnetic field inside the vacuum gap. The generation mechanism for the quasistatic magnetic fields is discussed in detail. It is found that the quasistatic fields continue to confine the high-energy electrons for longer than a few picoseconds. The double cones provide confinement and focusing of about 15% of the input energy for deposition in the compressed core.

Induction of cyp3a in primary cultures of human hepatocytes by ginkgolides a and B.

1. The present study was designed to determine the effects of ginkgolide A, ginkgolide B and quercetin on CYP3A protein expression and enzyme activity in primary cultures of human hepatocytes. 2. Hepatocytes were pretreated with ginkgolide A, ginkgolide B and quercetin (at 1, 3, 10 and 30 micromol/L) for 48 h and then exposed to testosterone (250 micromol/L) for 30 min. Rifampin (10 micromol/L) and phenobarbital (2 mmol/L) were used as positive controls. The CYP3A activity was measured by the amount of 6beta-hydroxytestosterone in the culture medium and CYP3A protein in hepatocyte lysate was semiquantified by immunoblotting. 3. Compared with the vehicle control, ginkgolides A and B, at 30 micromol/L, significantly induced CYP3A protein expression (2.1- and 2-fold, respectively; both P < 0.01) and markedly induced CYP3A-mediated testosterone 6beta-hydroxylation (2.5-fold each; P < 0.05 for ginkgolide A; P > 0.05 for ginkgolide B). Quercetin had no apparent induction. 4. Ginkgolide A and ginkgolide B can induce CYP3A protein expression and enzyme activity in primary cultures of human hepatocytes at higher doses.