scholarly journals Air leaks: stapling affects porcine lungs biomechanics

2021 ◽  
Author(s):  
Benedicte Bonnet ◽  
Ilyass Tabiai ◽  
George Rakovich ◽  
Frederick P Gosselin ◽  
Isabelle Villemure

During thoracic operations, surgical staplers resect cancerous tumors and seal the spared lung. However, post-operative air leaks are undesirable clinical consequences: staple legs wound lung tissue. Subsequent to this trauma, air leaks from lung tissue into the pleural space. This affects the lung's physiology and patients' recovery. The objective is to biomechanically and visually characterize porcine lung tissue with and without staples in order to gain knowledge on air leakage following pulmonary resection. Therefore, a syringe pump filled with air inflates and deflates eleven porcine lungs cyclically without exceeding 10 cmH2O of pressure. Cameras capture stereo-images of the deformed lung surface at regular intervals while a microcontroller simultaneously records the alveolar pressure and the volume of air pumped. The raw images are then used to compute tri-dimensional displacements and strains with the Digital Image Correlation method (DIC). Air bubbles originated at staple holes of inner row from exposed porcine lung tissue due to torn pleural on costal surface. Compared during inflation, left upper or lower lobe resections have similar compliance (slope of the pressure vs volume curve), which are 9% lower than healthy lung compliance. However, lower lobes statistically burst at lower pressures than upper lobes (p-value<0.046) in ex vivo conditions confirming previous clinical in vivo studies. In parallel, the lung deformed mostly in the vicinity of staple holes and presented maximum shear strain near the observed leak location. To conclude, a novel technique DIC provided concrete evidence of the post-operative air leaks biomechanics. Further studies could investigate causal relationships between the mechanical parameters and the development of an air leak.

Author(s):  
Jan Michael Burg ◽  
Veronika Flatten ◽  
Matthias Witt ◽  
Larissa Derksen ◽  
Uli Weber ◽  
...  

Abstract In particle therapy of lung tumors, modulating effects on the particle beam may occur due to the microscopic structure of the lung tissue. These effects are caused by the heterogeneous nature of the lung tissue and cannot be completely taken into account during treatment planning, because these micro structures are too small to be fully resolved in the planning CT. In several publications, a new material parameter called modulation power (P mod ) was introduced to characterize the effect. For various artificial lung surrogates, this parameter was measured and published by other groups and ranges up to approximately 1000 µm. Studies investigating the influence of the modulation power on the dose distribution during irradiation are using this parameter in the rang of 100 to 800 µm. More precise measurements for P mod on real lung tissue have not yet been published. In this work, the modulation power of real lung tissue was measured using porcine lungs in order to produce more reliable data of P mod for real lung tissue. For this purpose, ex-vivo porcine lungs were frozen in a ventilated state and measurements in a carbon ion beam were performed. Due to the way the lungs were prepared and transferred to a solid state, the lung structures that modulate the beam could also be examined in detail using micro CT imaging. An optimization of the established methods of measuring the modulation power, which takes better account of the typical structures within lung tissue, was developed as well.


2018 ◽  
Vol 65 (12) ◽  
pp. 2827-2836
Author(s):  
Charles Klassen ◽  
Chad E. Eckert ◽  
Jordan Wong ◽  
Jacques P. Guyette ◽  
Jason L. Harris ◽  
...  
Keyword(s):  
Ex Vivo ◽  

1994 ◽  
Vol 72 (05) ◽  
pp. 659-662 ◽  
Author(s):  
S Bellucci ◽  
W Kedra ◽  
H Groussin ◽  
N Jaillet ◽  
P Molho-Sabatier ◽  
...  

SummaryA double-blind, placebo-controlled randomized study with BAY U3405, a specific thromboxane A2 (TX A2) receptor blocker, was performed in patients suffering from severe stade II limb arteriopathy. BAY U3405 or placebo was administered in 16 patients at 20 mg four times a day (from day 1 to day 3). Hemostatic studies were done before therapy, and on day 2 and day 3 under therapy. On day 3, BAY U3405 was shown to induce a highly statistically significant decrease of the velocity and the intensity of the aggregations mediated by arachidonic acid (56 ± 37% for the velocity, 58 ± 26% for the intensity) or by U46619 endoperoxide analogue (36 ± 35% for the velocity, 37 ± 27% for the intensity). Similar results were already observed on day 2. By contrast, such a decrease was not noticed with ADP mediated platelet aggregation. Furthermore, plasma levels of betathrombo-globulin and platelet factor 4 remained unchanged. Peripheral hemodynamic parameters were also studied. The peripheral blood flow was measured using a Doppler ultrasound; the pain free walking distance and the total walking ability distance were determined under standardized conditions on a treadmill. These last two parameters show a trend to improvement which nevertheless was not statistically significant. All together these results encourage further in vivo studies using BAY U3405 or related compounds on a long-term administration.


Author(s):  
Y Madhusudan Rao ◽  
Gayatri P ◽  
Ajitha M ◽  
P. Pavan Kumar ◽  
Kiran kumar

Present investigation comprises the study of ex-vivo skin flux and in-vivo pharmacokinetics of Thiocolchicoside (THC) from transdermal films. The films were fabricated by solvent casting technique employing combination of hydrophilic and hydrophobic polymers. A flux of 18.08 µg/cm2h and 13.37µg/cm2h was achieved for optimized formulations containing 1, 8-cineole and oleic acid respectively as permeation enhancers. The observed flux values were higher when compared to passive control (8.66 µg/cm2h). Highest skin permeation was observed when 1,8-cineole was used as chemical permeation enhancer and it considerably (2-2.5 fold) improved the THC transport across the rat skin. In vivo studies were performed in rabbits and samples were analysed by LC-MS-MS. The mean area under the curve (AUC) values of transdermal film showed about 2.35 times statistically significant (p<0.05) improvement in bioavailability when compared with the oral administration of THC solution. The developed transdermal therapeutic systems using chemical permeation enhancers were suitable for drugs like THC in effective management of muscular pain.    


2019 ◽  
Vol 16 (7) ◽  
pp. 637-644 ◽  
Author(s):  
Hadas Han ◽  
Sara Eyal ◽  
Emma Portnoy ◽  
Aniv Mann ◽  
Miriam Shmuel ◽  
...  

Background: Inflammation is a hallmark of epileptogenic brain tissue. Previously, we have shown that inflammation in epilepsy can be delineated using systemically-injected fluorescent and magnetite- laden nanoparticles. Suggested mechanisms included distribution of free nanoparticles across a compromised blood-brain barrier or their transfer by monocytes that infiltrate the epileptic brain. Objective: In the current study, we evaluated monocytes as vehicles that deliver nanoparticles into the epileptic brain. We also assessed the effect of epilepsy on the systemic distribution of nanoparticleloaded monocytes. Methods: The in vitro uptake of 300-nm nanoparticles labeled with magnetite and BODIPY (for optical imaging) was evaluated using rat monocytes and fluorescence detection. For in vivo studies we used the rat lithium-pilocarpine model of temporal lobe epilepsy. In vivo nanoparticle distribution was evaluated using immunohistochemistry. Results: 89% of nanoparticle loading into rat monocytes was accomplished within 8 hours, enabling overnight nanoparticle loading ex vivo. The dose-normalized distribution of nanoparticle-loaded monocytes into the hippocampal CA1 and dentate gyrus of rats with spontaneous seizures was 176-fold and 380-fold higher compared to the free nanoparticles (p<0.05). Seizures were associated with greater nanoparticle accumulation within the liver and the spleen (p<0.05). Conclusion: Nanoparticle-loaded monocytes are attracted to epileptogenic brain tissue and may be used for labeling or targeting it, while significantly reducing the systemic dose of potentially toxic compounds. The effect of seizures on monocyte biodistribution should be further explored to better understand the systemic effects of epilepsy.


2018 ◽  
Vol 15 (6) ◽  
pp. 531-543 ◽  
Author(s):  
Dominik Szwajgier ◽  
Ewa Baranowska-Wojcik ◽  
Kamila Borowiec

Numerous authors have provided evidence regarding the beneficial effects of phenolic acids and their derivatives against Alzheimer's disease (AD). In this review, the role of phenolic acids as inhibitors of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) is discussed, including the structure-activity relationship. In addition, the inhibitory effect of phenolic acids on the formation of amyloid β-peptide (Aβ) fibrils is presented. We also cover the in vitro, ex vivo, and in vivo studies concerning the prevention and treatment of the cognitive enhancement.


2020 ◽  
Vol 10 ◽  
Author(s):  
Divya Thakur ◽  
Gurpreet Kaur ◽  
Sheetu Wadhwa ◽  
Ashana Puri

Background: Metronidazole (MTZ) is an anti-oxidant and anti-inflammatory agent with beneficial therapeutic properties. The hydrophilic nature of molecule limits its penetration across the skin. Existing commercial formulations have limitations of inadequate drug concentration present at target site, which requires frequent administration and poor patient compliance. Objective: The aim of current study was to develop and evaluate water in oil microemulsion of Metronidazole with higher skin retention for treatment of inflammatory skin disorders. Methods: Pseudo ternary phase diagrams were used in order to select the appropriate ratio of surfactant and co-surfactant and identify the microemulsion area. The selected formulation consisted of Capmul MCM as oil, Tween 20 and Span 20 as surfactant and co-surfactant, respectively, and water. The formulation was characterized and evaluated for stability, Ex vivo permeation studies and in vivo anti-inflammatory effect (carrageenan induced rat paw edema, air pouch model), anti-psoriatic activity (mouse-tail test). Results: The particle size analyses revealed average diameter and polydispersity index of selected formulation to be 16 nm and 0.373, respectively. The results of ex vivo permeation studies showed statistically higher mean cumulative amount of MTZ retained in rat skin from microemulsion i.e. 21.90 ± 1.92 μg/cm2 which was 6.65 times higher as compared to Marketed gel (Metrogyl gel®) with 3.29 ± 0.11 μg/cm2 (p<0.05). The results of in vivo studies suggested the microemulsion based formulation of MTZ to be similar in efficacy to Metrogyl gel®. Conclusion: Research suggests efficacy of the developed MTZ loaded microemulsion in treatment of chronic skin inflammatory disorders.


2019 ◽  
Vol 30 (1) ◽  
pp. 154-155
Author(s):  
Ambria S Moten ◽  
Abbas E Abbas

Abstract It has been previously suggested that lung tissue remains viable without blood supply from the pulmonary artery (PA). However, our experience demonstrates otherwise. We present 2 cases of accidental left lower lobe PA occlusion during upper lobectomy causing ischaemic changes to the remaining lung tissue. Both patients became septic secondary to necrosis of infarcted lung and required completion pneumonectomy. Development of collateral circulation to bypass the occluded PA may occur but is often insufficient to support the affected lung tissue. Unless the patient is medically unfit, resection of the ischaemic lung should be undertaken.


Marine Drugs ◽  
2021 ◽  
Vol 19 (2) ◽  
pp. 48
Author(s):  
Laura Micheli ◽  
Marzia Vasarri ◽  
Emanuela Barletta ◽  
Elena Lucarini ◽  
Carla Ghelardini ◽  
...  

Posidonia oceanica (L.) Delile is traditionally used for its beneficial properties. Recently, promising antioxidant and anti-inflammatory biological properties emerged through studying the in vitro activity of the ethanolic leaves extract (POE). The present study aims to investigate the anti-inflammatory and analgesic role of POE in mice. Inflammatory pain was modeled in CD-1 mice by the intraplantar injection of carrageenan, interleukin IL-1β and formalin. Pain threshold was measured by von Frey and paw pressure tests. Nociceptive pain was studied by the hot-plate test. POE (10–100 mg kg−1) was administered per os. The paw soft tissue of carrageenan-treated animals was analyzed to measure anti-inflammatory and antioxidant effects. POE exerted a dose-dependent, acute anti-inflammatory effect able to counteract carrageenan-induced pain and paw oedema. Similar anti-hyperalgesic and anti-allodynic results were obtained when inflammation was induced by IL-1β. In the formalin test, the pre-treatment with POE significantly reduced the nocifensive behavior. Moreover, POE was able to evoke an analgesic effect in naïve animals. Ex vivo, POE reduced the myeloperoxidase activity as well as TNF-α and IL-1β levels; further antioxidant properties were highlighted as a reduction in NO concentration. POE is the candidate for a new valid strategy against inflammation and pain.


Biomolecules ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 887
Author(s):  
Yun-Ju Huang ◽  
Yu-Chieh Chen ◽  
Hsin-Yuan Chen ◽  
Yi-Fen Chiang ◽  
Mohamed Ali ◽  
...  

Dysmenorrhea is one of the most prevalent disorders in gynecology. Historically, adlay (Coix lachryma-jobi L. var. Ma-yuen Stapf.) has been explored for its anti-tumor, pain relief, anti-inflammatory, and analgesic effects. The aim of this study was to evaluate the effects of adlay seeds on the inhibition of uterine contraction and thus dysmenorrhea relief, in vitro and in vivo. HPLC-MS and GC were used to elucidate the ethyl acetate fraction of adlay testa ethanolic extract (ATE-EA) and ethyl acetate fraction of adlay hull ethanolic extract (AHE-EA). Elucidation yielded flavonoids, phytosterols, and fatty acids. Uterine leiomyomas and normal adjacent myometrial tissue were evaluated by oxytocin- and PG-induced uterine contractility. ATE-EA and AHE-EA suppressed uterine contraction induced by prostaglandin F2 alpha (PGF2α), oxytocin, carbachol, and high-KCl solution ex vivo. In addition, the external calcium (Ca2+) influx induced contraction, and increased Ca2+ concentration was inhibited by ATE-EA and AHE-EA on the uterine smooth muscle of rats. Furthermore, ATE-EA and AHE-EA effectively attenuated the contraction of normal human myometrium tissues more than adjacent uterine leiomyoma in response to PGF2α. 3,5,6,7,8,3′,4′-Heptamethoxyflavone and chrysoeriol produced a remarkable inhibition with values of IC50 = 24.91 and 25.59 µM, respectively. The experimental results showed that treatment with ATE-EA at 30 mg/day effectively decreased the writhing frequency both on the oxytocin-induced writhing test and acetic acid writhing test of the ICR mouse.


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