Outside Of Vessel Research Articles

Abstract WMP110: Endogenous Angiogenic Cerebral Endothelial Cell Derived Small Extracellular Vesicles Actively Communicate to Neurons and Astrocytes After Stroke

While ex-vivo studies have shown that small extracellular vesicles (sEVs) isolated from cerebral endothelial cells (CEC-sEVs) can be internalized by neurons leading to enhancement of neurite remodeling, whether such communication are present in ischemic brain is not known. Using CEC-sEV reporter mice, we investigated whether endogenous CEC-sEV mediate communication between CECs and neural cells after stroke. A CEC-specific/sEV reporter mouse line was generated by crossing Slco1c1- CreERT2 mice with CD63-GFP loxP/loxP mice. The adult reporter mice were subjected to middle cerebral artery occlusion or sham operation after tamoxifen injection (n=4/group). 3D confocal microscopic analysis revealed that GFP signals in sham operated reporter mice were primarily localized within cerebral vessels, while extravascular GFP signals were also detected throughout the entire brain, suggesting that endogenous sEVs are specific to CECs and CEC-sEVs are released into brain parenchyma. Compared to the sham mice, ischemia induced robust angiogenesis in the peri-infarct areas assessed by increasing vascular density at day 7 and 42 post stroke, where the GFP signals within endothelium increased by 56% and 28%, respectively. The GFP signals within parenchyma (outside of vessels) of the peri-infarct areas were augmented by 21% and 24% at day 7 and 42 post stroke, respectively, suggesting that stroke increases CEC-sEVs secretion at peri-infarct angiogenic sites. Immunofluorescent staining showed that the increased parenchymal GFP signals in peri-infarct areas were localized within GFAP + astrocytes by 36% and 21% of total parenchymal GFP signals at day 7 and 42 post stroke, respectively. Moreover, the GFP signals within the peri-infarct MAP2 + neurons were significantly augmented by 22% at day 42 but not at day 7 after stroke compared to the sham group. Stroke did not alter GFP signals within IBA1 + microglia in the reporter mice. In conclusion, our in vivo data for the first time demonstrate that stroke increases the release of CEC-sEVs at peri-infarct angiogenic sites, where they actively communicate with astrocytes and neurons during stroke recovery. These data suggest that endogenous CEC-sEVs may regulate neurovascular function contributing to stroke recovery.

Customized 3D printed bioreactors for decellularization-High efficiency and quality on a budget.

Decellularization (DC) of biomaterials with bioreactors is widely used to produce scaffolds for tissue engineering. This study uses 3D printing to develop efficient but low-cost DC bioreactors. Two bioreactors were developed to decellularize pericardial patches and vascular grafts. Flow profiles and pressure distribution inside the bioreactors were optimized by steady-state computational fluid dynamics (CFD) analysis. Printing materials were evaluated by cytotoxicity assessment. Following evaluation, all parts of the bioreactors were 3D printed in a commercial fused deposition modeling printer. Samples of bovine pericardia and porcine aortae were decellularized using established protocols. An immersion and agitation setup was used as a control. With histological assessment, DNA quantification and biomechanical testing treatment effects were evaluated. CFD analysis of the pericardial bioreactor revealed even flow and pressure distribution in between all pericardia. The CFD analysis of the vessel bioreactor showed increased intraluminal flow rate and pressure compared to the vessel's outside. Cytotoxicity assessment of the used printing material revealed no adverse effect on the tissue. Complete DC was achieved for all samples using the 3D printed bioreactors while DAPI staining revealed residual cells in aortic vessels of the control group. Histological analysis showed no structural changes in the decellularized samples. Additionally, biomechanical properties exhibited no significant change compared to native samples. This study presents a novel approach to manufacturing highly efficient and low budget 3D printed bioreactors for the DC of biomaterials. When compared to standard protocols, the bioreactors offer a cost effective, fast, and reproducible approach, which vastly improves the DC results.

Suppression of runaway current by magnetic energy transfer in J-TEXT

For disruptions without mitigation, a large amount of thermal energy and poloidal magnetic energy will be dissipated inside the vacuum vessel (VV). A slow current quench may be accompanied by a large halo current, while a fast current quench often causes large eddy current, which will result in electromagnetic force. At the same time, fast current quench will induce strong toroidal electric field, which will result in a large fraction of runaway current and the hitting of runaway beam on first wall. The disruption mitigation is essential for large scale tokamak. The existing methods to mitigate disruptions, such as massive gas injection and resonant magnetic perturbations, are aimed at increasing the runaway generation threshold or the lose rate of runaway electrons. It may not work for ITER with Ip = 15 MA operation. The root of runaway generation is the large toroidal electric field induced by fast current quench and the large avalanche factor with high plasma current. The reduction of toroidal electric field is favor for the runaway suppression. The magnetic energy transfer (MET) based on electromagnetic coupling for disruption mitigation has been proposed on J-TEXT. It has the advantage of transferring the magnetic energy to outside of vessel by the electromagnetic coupling. It accelerates the current quench (CQ) rate and reduces the toroidal electric field at the same time. The runaway current has been suppressed by the MET system on J-TEXT. The experimental results show that the MET can reduce the energy dissipated in the VV by 20 % through transferring of energy to outside of VV. The MET can increase the CQ rate about 50.7 % and decrease the loop voltage about 35.3 %. The MET provides a new idea to transfer the magnetic energy and to suppress runaway current for disruption mitigation in future devices.

S2231 Successful Endoscopic Therapy of Acute Lower GI Bleeding From Serosal Vessel Within a Contained Perforation Abscess Cavity

INTRODUCTION: We present a case of successful colonoscopic therapy of bleeding from a serosal vessel within a contained perforation cavity. CASE DESCRIPTION/METHODS: A 66 year old woman developed severe necrotizing post ERCP pancreatitis with walled off necrosis, multiple abdominal abscesses, and duodenal and colon perforation. She was transferred for evaluation of recurrent lower gastrointestinal bleeding which had been managed with transfusions due to her severe comorbidities. CT showed multiple abdominal collections with the dominant peripancreatic collection communicating with the descending colon. Colonoscopy showed large amount of blood clots and ischemic looking ulcers from 30-35cm from the anus. The scope could not be passed beyond 35cm due to stricture. A cavity was seen at 30cm which corresponded to the perforation from the peripancreatic collection seen on CT. This was filled with large amount of clots. The patient was managed conservatively and discharged back to the nursing facility. She was transferred back 6 weeks later with worsening bleeding. Repeat CT showed worsening abdominal abscesses and a drainage catheter was placed in to the loculated collection near the descending colon. CT angiogram showed bleeding from the stomach. Endoscopy was unremarkable. Sigmoidoscopy showed the known cavity at 30cm which was filled with clots and red blood. The drainage catheter was seen within the cavity. Once blood was cleared a stigmata of recent hemorrhage was seen and obliterated with hemostatic forceps. The bleeding stopped and patient was discharged back to the nursing home. DISCUSSION: Our patient presented with lower gastrointestinal bleeding from a non-gastrointestinal source since her bleeding occurred from a vessel outside of the colon. The blood drained through the colon through the perforation which is why she did not have significant bleeding nor fluid output through her drain since they drained preferentially through the large colonic fistula. Recognition of the stigmata of recent hemorrhage within the abscess cavity and hemostasis resolved the bleeding. It is safe to endoscope cavities communicating with the gut, especially when they are chronic and also have external drainage as in our patient since any CO2 insufflation or irrigation would drain outside of the body. Therefore such cavities including peripancreatic walled off necrosis, abscess, or contained perforation could be evaluated for cause of bleeding which can be safely treated using conventional hemostasis.Figure 1.: Blood clots (triangle) filling the perforated abscess is seen on the left and colon lumen (arrow) on the right.Figure 2.: Stigmata of recent hemorrhage (arrow) seen after clots cleared.Figure 3.: Percutaneous drain (triangle) is seen on the left and obliterated stigmata (arrow) on the bottom.

Evaluation of Iridium_192 radioisotope dosimeter calculations for vascular Brachiotherapy

Introduction: One of the most effective means for treatment of coronary arteries cramp (CHD) is coronary intravascular Brachiotherapy. In this study, with use of MCNP code, in order to invastigating the score of ditribution of absorbed dose, drope in dose, and simulation mean, radiation doses around iridium_192 radioactive has been done. Materials and Methods: For this purpose, ORNL Fantum standard and human vessel has been chosen. In Fantum and simulation site, the rate of received dose from photon spring radiation with average energy about 0.38 Mg electron volt is well-performed. Results: Results show the importance of the amount of electron absorbed doses from photon interaction with a material in way of intravascular Brachiotherapy. This although shows that with the use of gama or photon, a great amount of dose will absorb in outside of vessel. This high amount in outside of vessel shows the importance of created electrons with use of interaction between photon and the material.

Analysis of the configurations and heat transfer of corium pool in RPV lower plenum

The corium containing stainless steel, partially oxidized zirconium cladding and fuel materials in the lower plenum may separate into immiscible liquids at high temperatures that influence the heat flux into vessel during in-vessel melt retention (IVR). In this work, the stratification of the corium in the lower plenum and the distribution of heat flux on the outside of vessel for AP1000 were assessed by three well-accepted 3-layer models developed by Esmaili & Khatib-Rahbar (model 1), Seiler (model 2), Salay & Fichot (model 3) respectively. In addition, the heat transfer in the corium is analyzed for a typical 1000 MWe Advanced PWR in China after a hypothetical station blackout accident. The results shown that the maximum heat flux of corium pool obtained by model 1 and 2 are both smaller than the CHF of AP600. Although it is slightly larger in model 2, enough safety margin is still retained compared with the CHF of AP1000.

음향방출 에너지 기반 손상 위치표정 기법을 이용한 복합재 CNG 탱크의 충격 신호 위치표정

음향방출기법은 구조물에 존재하는 손상 및 손상 메커니즘을 규명하는 가장 유효한 비파괴검사 수단으로 널리 이용되고 있다. 그러나 기존의 손상위치표정 기법은 탄성파 전파 속도에 크게 의존하는 기법의 한계에 의하여 복합재료 또는 이종의 재료로 구성된 구조물에서의 손상을 탐지하기 어려운 한계점을 가지고 있다. 최근 다양한 분야에서 사용되고 있는 압축천연가스(CNG) 저장용기는 무게와 강성의 효율을 위하여 복합재료를 사용하여 외부를 보강하는 새로운 형태의 구조를 사용하고 있다. 이러한 다층 복합소재의 사용으로 기존의 손상탐지기법으로는 저장용기의 외부에서 가해지는 충격 혹은 결함에 의한 저장탱크에 발생한 손상의 측정이 매우 어렵게 되었다. 이러한 한계를 극복하기 위하여 본 연구에서는 선행연구를 통하여 개발된 에너지 기반 contour D/B map 기법을 이용하여 4 가지 형식의 CNG 저장탱크에 발생한 외부 충격 신호의 손상 위치를 측정하였다. 각각의 형식의 저장탱크에서 측정된 손상 위치 결과를 비교 분석하여 새로운 기법의 측정 성능을 알아보았다. Acoustic emission (AE) is one of the most powerful techniques for detecting damages and identify damage location during operations. However, in case of the source location technique, there is some limitation in conventional AE technology, because it strongly depends on wave speed in the corresponding structures having heterogeneous composite materials. A compressed natural gas(CNG) pressure vessel is usually made of carbon fiber composite outside of vessel for the purpose of strengthening. In this type of composite material, locating impact damage sources exactly using conventional time arrival method is difficult. To overcome this limitation, this study applied the previously developed Contour D/B map technique to four types of CNG storage tanks to identify the source location of damages caused by external shock. The results of the identification of the source location for different types were compared.

Creating an arteriovenous fistula in patients with chronic kidney disease stage 5

Aim. Comparative assessment of microsurgical and traditional methods for creating an arteriovenous fistula for long-term hemodialysis in patients with chronic renal failure.Methods. Results of arteriovenous fistula surgeries for creating arteriovenous fistula for long-term hemodialysis in 169 patients with chronic renal failure in the period from 2008 to 2013 were analyzed. The main group included 87 patients in whom arteriovenous fistula was formed by microsurgery. For fistula thrombosis prophylaxis, 40 mg of nadroparin calcium (fraxiparine) was used in this group after surgery as a postoperative bolus, followed by 7 days subcutaneous administration. Arteriovenous fistula in patients of the main group underwent anti-thrombogenic treatment: paravasal tissues and vessel outside were irrigated by 1% sodium chloride methylthioninium (methylene blue) after the main phase of the operation, followed by lysine acetylsalicylate standard solution after 2 minutes. The control group included 82 patients in whom fistula was created conventionally without using microsurgical techniques. For arteriovenous fistula thrombosis prevention, 5000 IU of sodium heparin was used 4 times a day in patients of the control group.Results. In the main group, five cases of fistula thrombosis were observed in patients with diabetes mellitus and two in patients with chronic glomerulonephritis. In the control group, arteriovenous fistula thrombosis in the early postoperative period was recorded in 13 patients with diabetes mellitus, in four - with chronic glomerulonephritis, and in one - with polycystic kidney disease. In one (1.15%) patient of the main group and in three (3.66%) in the control group, wound infection associated with inflammatory processes development at the surgical wound was noted.Conclusion. Microsurgical formation of arteriovenous fistula in patients with terminal stage of chronic kidney disease is the method of choice (especially with concomitant diabetes mellitus), allowing to significantly reduce the risk for arteriovenous fistula thrombosis and therefore reduce the number of unsatisfactory results.

Feasibility of tissue characterization of coronary plaques using 320-detector row computed tomography: comparison with integrated backscatter intravascular ultrasound

Recently, a new generation of multi-detector row computed tomography (CT) with 320-detector rows (DR) has become available in the clinical settings. The purpose of the present study was to determine the cutoff values of Hounsfield unit (HU) for discrimination of plaque components by comparing HU of coronary plaques with integrated backscatter intravascular ultrasound (IB-IVUS) serving as a gold standard. Seventy-seven coronary atherosclerotic lesions in 77 patients with angina were visualized by both 320-DR CT (Aquilion One, Toshiba, Japan) and IB-IVUS at the same site. To determine the thresholds for discrimination of plaque components, we compared HU with IB values as a gold standard. Optimal thresholds were determined from receiver operating characteristic (ROC) curves analysis. The HU values of lipid pool (n = 115), fibrosis (n = 93), vessel lumen and calcification (n = 73) were 28 ± 19 HU (range -18 to 69 HU), 98 ± 31 HU (44 to 195 HU), 357 ± 65 HU (227 to 534 HU) and 998 ± 236 HU (366 to 1,489 HU), respectively. The thresholds of 56 HU, 210 HU and 490 HU were the most reliable predictors of lipid pool, fibrosis, vessel lumen and calcification, respectively. Lipid volume measured by 320-DR CT was correlated with that measured by IB-IVUS (r = 0.63, p < 0.05), whereas fibrous volume measured by 320-DR CT was not. Lipid volume measured by 320-DR CT was correlated with that measured by IB-IVUS, whereas fibrous volume was not correlated with that measured by IB-IVUS because manual exclusion of the outside of vessel hindered rigorous discrimination between fibrosis and extravascular components.

Angiotropism of Human Melanoma: Studies Involving In Transit and Other Cutaneous Metastases and the Chicken Chorioallantoic Membrane

Melanoma cell migration along the outside of vessels has been termed "extravascular migratory metastasis" (EVMM), as distinct from intravascular dissemination. Previous studies in both human and experimental melanoma models have shown angiotropism of melanoma cells, suggesting EVMM. Our objectives are to study the mechanism of dissemination of human melanoma cells in the chick chorioallantoic membrane (CAM) and to compare the histopathology in the CAM with that of patients with in transit and other cutaneous melanoma metastases. Human and murine melanoma cells were inoculated onto the CAM and observed over a 10-day period for tumor dissemination. Both human melanoma specimens from 26 patients and melanoma cells growing on the CAM showed the presence of tumor cell angiotropism at the invasive front of the tumor and at some distance from the tumor mass. In addition, a clear progression of melanoma cells spreading on the CAM was observed along the abluminal surface of vessels, where they occupied a perivascular location. By day 10 after injection, small micrometastases had developed along vessels, in a pattern similar to that in transit and other cutaneous melanoma metastases. In addition, the results suggested that the number of micrometastases directly correlated with increasing tumor volume. Taken together, these data suggest that the CAM is a relevant model for studying tumor cell dissemination, and that EVMM may be a mechanism by which some melanoma cells spread to nearby and even distant sites.

Pericyte-Like Location of GFP-Tagged Melanoma Cells: Ex Vivo and In Vivo Studies of Extravascular Migratory Metastasis

Previous studies have demonstrated that some tumor cells occupy a pericyte-like location in melanoma, forming angio-tumoral complexes. We hypothesized that these tumor cells are migrating along the abluminal surface of the endothelium, a mechanism termed "extravascular migratory metastasis." In the present study, we have used human and murine melanoma cells that stably express enhanced green fluorescence protein (GFP) to examine, in an ex vivo co-culture model, melanoma cell interactions with vessels that have sprouted from rat aortic rings. We also used in vivo tumor growth on the chick chorioallantoic membrane (CAM) to observe the dissemination pathway of melanoma cells. In the ex vivo rat aorta system, we observed a pericyte-like location of tumor cells that were spreading along the vascular channels. For examination of the CAM in vivo, we have used the Lugassy preparation, allowing one to obtain striking images of the relationship between fluorescent GFP cells and microvessels. Melanoma cells were found cuffing the outside of vessels around the tumor. Tumor cells were observed along the vessels several centimeters from the tumor. Confocal microscopy and histopathology confirmed the pericyte-like location of tumor cells, without any observable intravasation. The results indicate that melanoma cells can migrate along the abluminal surface of vessels. This study also demonstrates that these models can provide quantitation analysis that may prove useful in elucidating the molecular interactions involved in extravascular migratory metastasis.

Safety aspects of heavy metal-cooled accelerator-driven waste

Accelerator-driven, subcritical lead I bismuth cooled systems have several safety advantages. The critical accident initiators in such systems lead only to a relatively slow coolant heat-up that should be noticed by the reactor operators who will initiate a shutting down of the accelerator. This decreases the reactor power to decay heat levels. If the coolant temperature increase should go unnoticed, passive systems will lead to an automatic shutdown of the accelerator or a blocking of the proton beam. Emergency decay heat removal by natural air circulation cooling of the vessel outside is an attractive option for such a system. If no active or passive beam shut-off took place during a coolant overheating due to a significant Loss of Heat Sink (LOHS) accident, a core melt could eventually occur. Oxide fuel would probably mix with the heavy metal coolant with its high boiling point and circulate in the primary system in a coolable fashion. This type of scenario seems to have happened in a core melt accident in a Russian Alpha submarine with its lead / bismuth cooled critical reactor.

A Review of Corrosion Resistant Linings

Introduction There is more than sufficient information available to consultant, design, production and works engineers with respect to protective paint systems for the outside of vessels, but a very limited amount of literature readily accessible when one considers internal protection. Although BS CP 3003, and to some extent CP 2008 with BS 570. 2594, 2654 and 4950 assist with basic concepts, it has become apparent that many engineers would welcome brief non‐technical details of the range of linings available.

A PRACTICAL APPARATUS FOR ASPIRATING AND WASHING THE PLEURA

This apparatus works on the principle of withdrawing the purulent exudate, at the same time introducing into the pleura a mild antiseptic solution, following which air can be sub-stituted. It consists of a graduated bottle containing 1,000 cc., and a cork with two openings into which pass two metal tubes. The right tube is connected to a rubber bulb. The left tube is connected to an especially constructed cock with four openings. The upper opening of the cock connects by a metal tube to the inside of the bottle; the left opening is connected to a pleura needle. The lower opening is connected by a rubber tube to a 100 cc. glass syringe. The right opening is a metal tube with a two way cock so that when the cock is open, fluid can be forced from the pleura to a receiving vessel outside; or, if the cock