Fabrications of small diameter compliance bypass conduit using electrospinning of clinical grade polyurethane

Objective Compliance and viscoelastic mismatches of small diameter vascular conduits and host arteries have been the cause of conduit’s failure. Methods To reduce these mismatches, the aim of this study was to develop and characterize a polyurethane conduit, which mimics the viscoelastic behaviors of human arteries. Electrospinning technique was used to fabricate tubular polyurethane conduits with similar properties of the human common carotid artery. This was achieved by manipulating the fiber diameter by altering the syringe flow rate of the solution. The mechanical and viscoelastic properties of the fabricated electrospun polyurethane conduits were, then, compared with commercially available vascular conduits, expanded polytetrafluoroethylene, polyethylene terephthalate (Dacron®) and the healthy human common carotid arteries. In addition, a comprehensive constitutive model was proposed to capture the visco-hyperelastic behavior of the synthetic electrospun polyurethanes, commercial conduits and human common carotid arteries. Results Results showed that increasing the fiber diameter of electrospun polyurethanes from 114 to 190 nm reduced Young’s modulus from 8 to 2 MPa. Also, thicker fiber diameter yielded in higher conduits’ viscosity. Furthermore, the results revealed that proposed visco-hyperelastic model is strongly able to fit the experimental data with great precision which proofs the reliability of the proposed model to address both nonlinear elasticity and viscoelasticity of the electrospun polyurethanes, commercial conduits and human common carotid arteries. Conclusions In conclusion, statistical analysis revealed that the elastic and viscous properties of 190 nm fiber diameter conduit are very similar to that of human common carotid artery in comparison to the commercial expanded polytetrafluoroethylene and Dacron® that are up to nine and seven times stiffer than natural vessels. Therefore, based on our findings, from the mechanical point of view, by considering the amount of Young’s modulus, compliance, distensibility and viscoelastic behavior, the fabricated electrospun polyurethane with fiber diameter of 189.6 ± 52.89 nm is an optimum conduit with promising potential for substituting natural human vessels.

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Synchronous Carotid Bifurcation Endarterectomy and Retrograde Kissing Stenting of the Innominate and Left Common Carotid Artery in a Patient with a Bovine Aortic Arch

Case Reports in Surgery ◽

10.1155/2017/4239829 ◽

2017 ◽

Vol 2017 ◽

pp. 1-4 ◽

Cited By ~ 1

Author(s):

Alessandro Robaldo ◽

Guido Carignano ◽

Alberto Balderi ◽

Claudio Novali

Keyword(s):

Carotid Artery ◽

Aortic Arch ◽

Common Carotid Artery ◽

Carotid Arteries ◽

High Risk Patient ◽

Carotid Bifurcation ◽

Left Common Carotid Artery ◽

The Right ◽

Bovine Aortic Arch ◽

Common Carotid Arteries

Management of the symptomatic multiple stenosis of supra-aortic vessels (MSSVs) in a “bovine” aortic arch (BAA) configuration is infrequently reported. The optimal treatment choice remains debatable. A successful hybrid treatment for a proximal critical stenosis of the innominate and left common carotid artery was performed in a high-risk patient with a tandem symptomatic lesion in the right carotid bifurcation and a concentric vulnerable plaque in the bovine trunk. This case supports the feasibility, safety, and efficacy of a combined carotid bifurcation endarterectomy and retrograde kissing stenting of common carotid arteries with cerebral protection after evaluation of radiological, anatomical, and clinical parameters.

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Acute Effects of Whole-Body Vibration on Dopplerfluxometry of the Common Carotid Artery Parameters among Adult and Elderly Non-Athletes Healthy Dogs

Acta Scientiae Veterinariae ◽

10.22456/1679-9216.104506 ◽

2020 ◽

Vol 48 ◽

Author(s):

Lais Rosa Nagai ◽

Sheila Canevese Rahal ◽

Carmel Dadalto ◽

Bruna Martins Da Silva ◽

Miriam Tsunemi ◽

...

Keyword(s):

Carotid Artery ◽

Common Carotid Artery ◽

Carotid Arteries ◽

Whole Body ◽

Acute Effects ◽

Single Session ◽

Healthy Dogs ◽

The Common ◽

Common Carotid Arteries ◽

Systolic Peak Velocity

Background: Whole-Body Vibration (WBV) is an oscillatory mechanical stimulus spreading throughout the body and considered a type of physical exercise because of the activation of the cardiovascular, musculoskeletal, and neuroendocrine systems. It is a physical exercise modality since it promotes cardiovascular resistance, increase in muscular strength and neurosensitivity, and motor coordination improvement. For use of WBV as an exercise modality for dogs, it is necessary to evaluate the Dopplerfluxometry parameters of the common carotid artery in healthy dogs in order to perform a safe protocol without inducing any cerebral alteration. This study aimed to evaluate the acute effects of WBV on systolic peak velocity (SPV), resistivity (RI), and pulsatility index (PI) of the both common carotid artery among adults and elderly non-athletes healthy dog.Materials, Methods & Results: Fourteen clinically healthy, neutered crossbreed male dogs, non-athlete were divided into two groups of seven dogs, according to the age group: Group 1 (G1)- Adult dogs: age between 12 and 84 months; Group 2 (G2)- Elderly dogs: aged over 84 months. All dogs were submitted to sessions of WBV using the protocol of 30 Hz for 5 min, followed by an increase to 50 Hz for 5 more min and ending with 5 min at 30 Hz, without rest between the variation of the vibration frequency. The systolic peak velocity (SPV), resistivity (RI), and pulsatility index (PI) of the common carotid artery were assessed in two time-points: 5 min before the WBV sessions (5PRE) and 1 min after the WBV (1POS). No significant variations in the SPS, RI, and PI of both common carotid artery of the G1 and G2 were identified. The anatomic reference for the left and right common carotid artery was the right and left extern jugulars veins, which were identified by the venous blood vessel characteristics as endothelium type, and single-phase without systolic peaks wave. Discussion: In humans, WBV is indicated to muscle size and tone increase, therefore it is believed that this modality can present a beneficial result in dogs with muscular atrophy associated with orthopedic surgeries and in cases of osteoarthritis. Irreversible brain damage can be caused by a possible hemodynamic alteration in the common carotid arteries resulted from mechanical vibrations. Parkinson’s disease patients and individuals affected by strokes that went under acute sessions of WBV showed handshake reduction and better proprioception, respectively. The beneficial effect was observed in cervix opening in dogs with metritis. The behavior of sitting of the dogs over 30 kg during WBVsessions was associated with paraparesis. This result was present in medium-size non-athletic dogs weighing from 10.1 to 17.9 kg that went through WBV for 5 consecutive days, using the same vibrating platform. No signs of discomfort during a single session of 10 min of WBV (15 and 21 Hz) were observed in healthy adult horses. Studies using mechanical vibrations on adult healthy dogs did not show significant variation RI of the renal artery. On the other hand, daily use of WBV for 5 days on dogs showed significant enhancement on RI of the femoral artery immediately after it. A single session of WBV (30 and 50 Hz did, for 15 min) do not produce undesirable effects on SPV, RI, and PI of both common carotid arteries in adult and elderly non-athletic healthy dogs.

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Intimomedial thickness of the vertebral arteries complex: A new useful parameter for the assessment of atheroclerotic process?

Vojnosanitetski pregled ◽

10.2298/vsp1109733j ◽

2011 ◽

Vol 68 (9) ◽

pp. 733-738 ◽

Cited By ~ 1

Author(s):

Olivera Jovanikic ◽

Toplica Lepic ◽

Ranko Raicevic ◽

Dragana Veljancic ◽

Andjelka Ristic ◽

...

Keyword(s):

Carotid Artery ◽

Vertebral Artery ◽

Common Carotid Artery ◽

Carotid Arteries ◽

Mean Value ◽

Vertebral Arteries ◽

Significant Difference ◽

The Common ◽

Carotid Circulation ◽

Common Carotid Arteries

Bacground/Aim. An integral part of Doppler ultrasound examination of cervical blood vessels is determination of intimomedial thicknes (IMT) of the common carotid. The aim of the study was to estimate the relations between IMT of the common carotid and vertebral arteries in order to determine if the value of IMT obtained on the vertebral artery could be applied in clinical practice. Methods. We measured IMT in a randomized, prospective and crosssectional study, performed on 50 persons both sexes (29 men and 21 women), at the age from 18 to 79 years (mean age 52.4 ? 17.63 years). All the persons were healthy, what was confirmed with clinical examination and laboratory analyses. Measurements were perfomed from January 2006 until September 2008. Intimomedial thickness was recorded by twodimensional ultrasonography in B-mode on both common carotid arteries: one value was obtained as average of three successeful measurements (measurements were perform on different places). We measured IMT on the first segment of both vertebral arteries, 1.5 cm proximal from the connection of the first and second segments (we got results of the measurement of IMT on the vertebral arteries in the same way: mean value from the three records). Results. (IMT = 0.782 ? 0.248 mm), obtained from 50 healthy persons, was higher than that measured on the vertabral artery on the first segment (IMT = 0.585 ? 0.134 mm). The values of IMT after measurement on two different places were statistically highly different (t = 7.03, SD = 0.028, p < 0.01). Coefficient of variability of IMT values in carotid circulation (CV = 34.4%) was higher than that in vertebral circulation (22.9%). Values of IMT on vertebral arteries were in statistically significant correlation with those in carotid circulation (r = 0.24 and t- = 2.48; p < 0.02). There were no statistically significant difference between IMT measurement on the right and the left side so they were analysed as the same set Conclusion. Values of IMT on the vertebral arteries are one more undependent parameter of doplersonographic examination of cervical vessels, which significantly correlates with IMT values on common carotid artery. Variability of this parameter is lower, and absolute values lower than the same in the common carotid artery. Therefore, this parameter is probably not so sensitive. On the other hand, lower variability of IMT values on the vertebral artery might be of higher specificity for prediction of atherosclerotic progress by the increased values of this parameter than based on IMT values obtained on the common carotid arteries.

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A New Technique to Induce Experimental Myointimal Hyperplasia

Medical Principles and Practice ◽

10.1159/000492575 ◽

2018 ◽

Vol 27 (5) ◽

pp. 415-419

Author(s):

Sami Asfar ◽

Ali Shuaib ◽

Fatemah Al-Otaibi ◽

Sora S. Asfar ◽

Narayana Kilarkaje

Keyword(s):

Carotid Artery ◽

Common Carotid Artery ◽

Carotid Arteries ◽

Contralateral Side ◽

External Carotid Artery ◽

External Carotid ◽

The Common ◽

A New Technique ◽

Histopathological Studies ◽

Common Carotid Arteries

Background: Arterial myointimal hyperplasia (MIH) has a significant impact on the long-term outcomes of vascular procedures such as bypass surgery and angioplasty. In this study, we describe a new and innovative technique to induce MIH using a dental flossing cachet in Wistar rats. Methods: The intimal damage in the common carotid artery was induced by inserting the tip of the dental flossing cachet through the external carotid artery into the common carotid artery and turning it on for 3 rounds of 20 s each (n = 10). After 2 weeks, the rats were anesthetized and the common carotid arteries of the experimental side and the contralateral side (control) were harvested and preserved for histopathological studies. Results: The experimental carotid arteries showed significant intimal proliferation and thickening compared to the controls. The intima/media ratio of the experimental and normal (control) common carotid arteries were 1.274 ± 0.162 and 0.089 ± 0.023 (mean ± SEM), respectively (p < 0.001). Conclusion: This technique is simple, inexpensive, and highly reproducible and it induces sufficient MIH to study this phenomenon in animal models.

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Endovascular Treatment of Aneurysmal Subarachnoid Hemorrhage Associated with Bilateral Common Carotid Artery Occlusion

Interventional Neuroradiology ◽

10.1177/159101990801400411 ◽

2008 ◽

Vol 14 (4) ◽

pp. 447-452 ◽

Cited By ~ 3

Author(s):

T. Meguro ◽

T. Tanabe ◽

K. Muraoka ◽

K. Terada ◽

N. Hirotsune ◽

...

Keyword(s):

Carotid Artery ◽

Common Carotid Artery ◽

Carotid Arteries ◽

Posterior Cerebral Artery ◽

Artery Occlusion ◽

Carotid Artery Occlusion ◽

Double Balloon ◽

Bilateral Common Carotid Artery ◽

Common Carotid Artery Occlusion ◽

Common Carotid Arteries

Cases of aneurysm associated with the occlusion of both common carotid arteries are very rare. We present a case of ruptured aneurysms of the basilar bifurcation and posterior cerebral artery coexisting with bilateral common carotid artery occlusion, successfully treated by endovascular coil embolization with a double-balloon remodeling technique. Finally, we review the literature. A 62-year-old woman presented with severe headache; a computed tomography scan demonstrated subarachnoid hemorrhage. Angiography revealed that the bilateral common carotid arteries were occluded. The muscle branches of the vertebral arteries had anastomosed to the bilateral external carotid arteries. Bilateral posterior communicating arteries had developed and supplied the bilateral internal carotid arteries. Two aneurysms (a saccular aneurysm of the P1 portion of the left posterior cerebral artery and a wide-necked aneurysm of the basilar bifurcation) were also observed. Endovascular embolization of the aneurysms was successfully performed using a double-balloon remodeling technique. The patient made a full recovery after treatment, and the aneurysms remained obliterated 12 months after embolization. We believe that this is the first report of ruptured aneurysms associated with bilateral common carotid artery occlusion successfully treated by endovascular coiling. The double-balloon remodeling technique was useful for treatment of wide-necked basilar bifurcation aneurysm.

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Tortuous Common Carotid Artery: A Report of Four Cases Observed in Cadaveric Dissections

Case Reports in Otolaryngology ◽

10.1155/2016/2028402 ◽

2016 ◽

Vol 2016 ◽

pp. 1-4 ◽

Cited By ~ 3

Author(s):

Joe Iwanaga ◽

Koichi Watanabe ◽

Saga Tsuyoshi ◽

Yoko Tabira ◽

Koh-ichi Yamaki

Keyword(s):

Computed Tomography ◽

Thyroid Gland ◽

Carotid Artery ◽

Common Carotid Artery ◽

Carotid Arteries ◽

Vascular Wall ◽

Anatomical Dissection ◽

First Case ◽

Study Results ◽

Common Carotid Arteries

A tortuous common carotid artery poses a high risk of injury during tracheotomy. Preoperative diagnosis is therefore important to avoid serious complications. We found four cases of tortuous common carotid artery during an anatomical dissection course for students. The first case was a 91-year-old woman who had bilateral tortuous common carotid arteries without arteriosclerosis. Case2was a 78-year-old woman who had bilateral tortuous common carotid arteries without arteriosclerosis. Case3was an 86-year-old woman who died from bladder cancer and who also had a right tortuous common carotid artery without arteriosclerosis. Case4was an 89-year-old woman who had bilateral tortuous common carotid arteries and a tortuous brachiocephalic artery with severe arteriosclerosis. Case4was also examined using computed tomography to evaluate the arteriosclerosis. Computed tomography revealed severe calcification of the vascular wall, which was confirmed in the aortic arch and origins of its branches. In all four cases, the tortuosity was located below the level of the thyroid gland. Based on prior study results indicating that fusion between the carotid sheath and visceral fascia was often evident at the level of the thyroid gland, we speculated that the major region in which tortuosity occurs is at the same level or inferior to the level of the thyroid gland.

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Histological disorders of neurons of phylogenetically different parts of the cerebral cortex in partial, subtotal, stepwise subtotal, and total cerebral ischemia

Journal of Medical Science ◽

10.20883/medical.e493 ◽

2021 ◽

Vol 90 (1) ◽

pp. e493

Author(s):

Lizaveta I. Bon ◽

Nataliya Y. Maksimovich

Keyword(s):

Cerebral Ischemia ◽

Carotid Artery ◽

Parietal Cortex ◽

Common Carotid Artery ◽

Carotid Arteries ◽

Morphological Changes ◽

Oxygen Deficiency ◽

Progressive Increase ◽

Histological Changes ◽

Common Carotid Arteries

Aim. Measure of the histological changes in neurons in the parietal cortex and hippocampus of rats with partial, subtotal, stepwise subtotal, and total cerebral ischemia. Material and Methods. Studies were performed on 84 rats. Partial cerebral ischemia was modelled by ligation of one common carotid artery. Subtotal cerebral ischemia was modelled by ligation of both common carotid arteries. Stepwise subtotal cerebral ischemia was performed by sequential ligation of both common carotid artery with 7-day, 3-day or 1-day intervals. Total cerebral ischemia (CI) was modelled by decapitation. Results. When comparing the morphological changes of neurons in the parietal cortex and hippocampus, we observed that, with the aggravation of the severity of cerebral ischemia, there was a progressive increase in the number of hyperchromic shrivelled neurons and neurons with pericellular oedema. Modelling of more severe types of ischemic damage lead to pronounced morphological changes in neurons – a decrease in size, deformation of the perikaryon, and increase in the degree of neuronal chromatophilia with their wrinkling. Conclusions. The smallest morphological changes in neurons were noted in the partial cerebral ischemia groups and subgroup 1 of stepwise subtotal cerebral ischemia, with an interval between common carotid artery dressings of 7 days. The most obvious morphological changes were observed in the conditions of total cerebral ischemia after 1 day. Changes in the parietal cortex and hippocampus were unidirectional, but in the parietal cortex, which is most sensitive to oxygen deficiency, they were more pronounced.

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The content of ATP Synthase in Cerebral Ischemia of Varying Severity Comparative Analysis

Biotechnology and Bioprocessing ◽

10.31579/2766-2314/064 ◽

2022 ◽

Vol 3 (1) ◽

pp. 01-07

Author(s):

Bon Elizaveta I. ◽

Maksimovich Natalia E. ◽

Karnyushko Olga A. ◽

Zimatkin Sergey M ◽

Lychkovskaya Maria A

Keyword(s):

Cerebral Ischemia ◽

Carotid Artery ◽

Atp Synthase ◽

Parietal Cortex ◽

Common Carotid Artery ◽

Carotid Arteries ◽

Immunohistochemical Method ◽

The Common ◽

Common Carotid Arteries ◽

The Brain

Objective. Evaluation of changes in the content of ATP synthase in the parietal cortex and hippocampus of the brain of rats with ischemia of varying severity in a comparative aspect. Methods. The experiments were performed on 88 male outbred white rats weighing 260 ± 20 g. Brain ischemia was modeled under conditions of intravenous thiopental anesthesia (40-50 mg / kg). Total cerebral ischemia was modeled by decapitation of animals. The brain sampling was carried out 1 hour and 24 hours after decapitation - to study tissue respiration of mitochondria, as well as 1 hour later to determine the content of ATP synthase. Subtotal cerebral ischemia was modeled by simultaneous ligation of both common carotid arteries. The material was taken after 1 hour to determine the content of ATP synthase. Stepwise subtotal cerebral ischemia was performed by sequential ligation of both common carotid arteries with an interval of 7 days. The sampling was carried out 1 hour after ligation of the second common carotid artery in each of the subgroups. Partial cerebral ischemia was modeled by ligation of one common carotid artery on the right. The sampling was carried out 1 hour after the operation. Determination of the content of ATP synthase was carried out by immunohistochemical method using monoclonal antibodies. For this purpose, after decapitation, the brain was quickly removed from the rats, pieces of the cerebral cortex were fixed in zinc-ethanol-formaldehyde at + 4 ° C (overnight), then embeddedвinвparaffin. Results. In the group of stepwise subtotal cerebral ischemia, the smallest decrease in the content of ATP synthase was observed in the 1st subgroup with an interval between dressings of 7 days, while the greatest decrease in the content of the enzyme was noted in the 3rd subgroup with the minimum interval between the dressings of the common carotid artery (1 day). Modeling of more severe types of ischemic damage led to pronounced morphological changes in neurons in the parietal cortex and hippocampus of the rat brain - a decrease in their size, deformation of the perikarya, an increase in the degree of neuronal chromatophilia with their simultaneous wrinkling and subsequent death. These disorders were most pronounced in the 3rd subgroup of stepwise subtotal cerebral ischemia with the shortest interval between dressings, which was 1 day, and in the group of total cerebral ischemia. Conclusion. Thus, the most pronounced decrease in the content of ATP synthase was observed in the groups of total cerebral ischemia, subtotal cerebral ischemia and in the 3rd subgroup of stepwise subtotal cerebral ischemia, with a minimal time interval between the ligation of the common carotid artery. In stepwise subtotal cerebral ischemia with an interval between ligation of the common carotid artery of 7 days, the suppression of the ATP synthase content was not so significant.

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The Structure and the Mechanical Properties of a Newly Fabricated Cellulose-Nanofiber/Polyvinyl-Alcohol Composite

MRS Proceedings ◽

10.1557/opl.2014.141 ◽

2014 ◽

Vol 1621 ◽

pp. 149-154

Author(s):

Yukako Oishi ◽

Atsushi Hotta

Keyword(s):

Electron Microscopy ◽

Mechanical Properties ◽

Young’S Modulus ◽

Young's Modulus ◽

Cellulose Nanofibers ◽

Small Diameter ◽

Short Fiber ◽

Cellulose Nanofiber ◽

Process Conditions ◽

Aspect Ratios

ABSTRACTCellulose nanofibers (Cel-F) were extracted by a simple and harmless Star Burst (SB) method, which produced aqueous cellulose-nanofiber solution just by running original cellulose beads under a high pressure of water in the synthetic SB chamber. By optimizing the SB process conditions, the cellulose nanofibers with high aspect ratios and the small diameter of ∼23 nm were obtained, which was confirmed by transmission electron microscopy (TEM). From the structural analysis of the Cel-F/PVA composite by the scanning electron microscopy (SEM), it was found that the Cel-F were homogeneously dispersed in the PVA matrix. Considering the high molecular compatibility of the cellulose and PVA due to the hydrogen bonding, a good adhesive interface could be expected for the Cel-F and the PVA matrix. The influences of the morphological change in Cel-F on the mechanical properties of the composites were analysed. The Young’s modulus rapidly increased from 2.2 GPa to 2.9 GPa up to 40 SB treatments (represented by the unit Pass), whereas the Young’s modulus remained virtually constant above 40 Pass. Due to the uniform dispersibility of the Cel-F, the Young’s modulus of the 100 Pass composite at the concentration of 5 wt% increased up to 3.2 GPa. The experimental results corresponded well with the general theory of the composites with dispersed short-fiber fillers, which clearly indicated that the potential of the cellulose nanofibers as reinforcement materials for hydrophilic polymers was sufficiently confirmed.

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Pulmonary and systemic vascular smooth muscle mechanical characteristics in newborn sheep

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.1992.263.3.h881 ◽

1992 ◽

Vol 263 (3) ◽

pp. H881-H886 ◽

Cited By ~ 3

Author(s):

J. Belik ◽

A. J. Halayko ◽

K. Rao ◽

N. L. Stephens

Keyword(s):

Carotid Artery ◽

Age Differences ◽

Carotid Arteries ◽

Mechanical Characteristics ◽

Pulmonary Arteries ◽

Developmental Differences ◽

Lower Stress ◽

Optimal Length ◽

Vascular Muscle ◽

Common Carotid Arteries

To investigate the hypothesis that the higher pulmonary vascular resistance in newborn sheep is the result of developmental differences in the vascular muscle mechanical properties, we evaluated pulmonary arteries from newborn and adult sheep and compared them with their respective systemic counterparts (common carotid arteries). The newborn pulmonary artery mechanical stress (13.0 +/- 1.4 mN/mm2) and shortening capacity (11.4 +/- 1.1% of optimal length) were lower (P less than 0.01) than in the adult (20.4 +/- 2.5 and 15.6 +/- 1.3, respectively). The adult carotid artery muscle developed a greater stress (97.6 +/- 18.5 mN/mm2) than the newborn (40.7 +/- 5.0; P less than 0.01), whereas no age differences in shortening capacity were observed (newborn = 19.4 +/- 1.7; adult = 18.4 +/- 1.5% of optimal length). The contraction half-time was similar for the pulmonary and carotid arteries and was not affected by age, whereas the relaxation half-times of the newborn pulmonary (30.7 +/- 2.9 s) and carotid artery (23.3 +/- 1.5) were greater than in the adult (24.9 +/- 2.9 and 14.6 +/- 1.4, respectively; P less than 0.01). The myosin contents of the pulmonary and carotid arteries, as an indicator of the tissue muscle mass, were similar and did not change with age. In conclusion, while the lower stress and shortening capacity of the newborn pulmonary arteries limit their maximum capacity to vasoconstrict, the significantly greater relaxation time of their vascular muscle, a new observation, may account for the higher resistance to blood flow after birth.

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