Antegrade in situ fenestration of aortic stent graft: in-vivo experiments using a pig model

2012 ◽  
Vol 53 (7) ◽  
pp. 754-758 ◽  
Author(s):  
Petri Saari ◽  
Markku Lähteenvuo ◽  
Krista Honkonen ◽  
Hannu Manninen
Keyword(s):  
Stent Graft ◽  
Pig Model ◽  
In Vivo Experiments ◽  
Aortic Stent Graft

scholarly journals Enlisting the Ixodes scapularis Embryonic ISE6 Cell Line to Investigate the Neuronal Basis of Tick—Pathogen Interactions

Pathogens ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 70
Author(s):  
Lourdes Mateos-Hernández ◽  
Natália Pipová ◽  
Eléonore Allain ◽  
Céline Henry ◽  
Clotilde Rouxel ◽  
...  
Keyword(s):  
Cell Line ◽  
Peripheral Nerves ◽  
Ixodes Scapularis ◽  
Embryonic Cell ◽  
Cell Subpopulation ◽  
In Vivo Experiments

Neuropeptides are small signaling molecules expressed in the tick central nervous system, i.e., the synganglion. The neuronal-like Ixodes scapularis embryonic cell line, ISE6, is an effective tool frequently used for examining tick–pathogen interactions. We detected 37 neuropeptide transcripts in the I. scapularis ISE6 cell line using in silico methods, and six of these neuropeptide genes were used for experimental validation. Among these six neuropeptide genes, the tachykinin-related peptide (TRP) of ISE6 cells varied in transcript expression depending on the infection strain of the tick-borne pathogen, Anaplasma phagocytophilum. The immunocytochemistry of TRP revealed cytoplasmic expression in a prominent ISE6 cell subpopulation. The presence of TRP was also confirmed in A. phagocytophilum-infected ISE6 cells. The in situ hybridization and immunohistochemistry of TRP of I. scapularis synganglion revealed expression in distinct neuronal cells. In addition, TRP immunoreaction was detected in axons exiting the synganglion via peripheral nerves as well as in hemal nerve-associated lateral segmental organs. The characterization of a complete Ixodes neuropeptidome in ISE6 cells may serve as an effective in vitro tool to study how tick-borne pathogens interact with synganglion components that are vital to tick physiology. Therefore, our current study is a potential stepping stone for in vivo experiments to further examine the neuronal basis of tick–pathogen interactions.

Phosphofructokinase activity and acidosis during short-term tetanic contractions

1991 ◽  
Vol 69 (2) ◽  
pp. 298-304 ◽  
Author(s):  
Lawrence L. Spriet
Keyword(s):  
Glycolytic Enzyme ◽  
Test Tube ◽  
Mammalian Skeletal Muscle ◽  
Short Term ◽  
Short Supply ◽  
In Vivo Experiments ◽  
Anaerobic Energy

Anaerobic energy production is essential for the production of muscular tension when the demand for energy is greater than can be provided aerobically and when oxygen is in short supply. The largest source of anaerobic energy is from the glycolytic pathway. With sustained tetanic contractions, muscle glycolytic activity is high and hydrogen ions (H+) accumulate while tension production decreases. The increasing [H+] and decreasing tension led to the suggestion that H+ inhibits the activity of the regulatory glycolytic enzyme phosphofructokinase (PFK). Early in vitro work confirmed the H+ sensitivity of PFK in the test tube, indicating that little PFK activity should persist at a pH of 6.9–7.0. However, in situ and in vivo experiments suggested that significant PFK activity was maintained during intense contractions when muscle pH decreased to 6.4–6.6. There are several concerns associated with the application of in vitro findings to in vivo exercise situations: (i) there is little in vitro work in mammalian skeletal muscle with substrate and modulator concentrations representative of exercise, (ii) most in vitro analyses of PFK activity are performed following the dilution of the enzyme in mediums with low protein concentration, and (iii) do the modulators identified in vitro exist in high enough in vivo concentrations at rest and during exercise to contribute to the regulation of PFK? More recent in vitro and in situ PFK experiments have overcome some of these concerns. They confirm that during intense, short-term tetanic contractions, PFK activity is well matched to the ATP demand despite decreases in pH to ~6.4–6.5. A combination of decreased inhibitor (ATP) and increased substrate (fructose 6-phosphate) contents coupled with increases in the contents of several positive modulators may be responsible for the maintained PFK activity. This combination reduces the pH-dependent ATP inhibition of PFK and extends the physiological pH range of the enzyme to the range normally measured during this type of muscular activity.Key words: glycolysis, phosphofructokinase, anaerobic metabolism, acidosis.

Emergency aortic stent-graft treatment for malignant aortoesophageal fistula

2017 ◽  
Vol 25 (9) ◽  
pp. 649-652 ◽  
Author(s):  
Pak Chiu Wong ◽  
Yiu Che Chan ◽  
Yuk Law ◽  
Stephen Wing Keung Cheng
Keyword(s):  
Stent Graft ◽  
Esophageal Neoplasms ◽  
Locally Advanced ◽  
Hemodynamic Instability ◽  
Sudden Onset ◽  
Aortoesophageal Fistula ◽  
Aortic Stent Graft ◽  
Esophageal Tumors ◽  
Massive Hematemesis

Two patients with locally advanced squamous cell carcinoma of the mid-esophagus, with esophageal stents in situ, suffered sudden onset of massive hematemesis and hemodynamic instability due to an aortoesophageal fistula. Although their esophageal neoplasms were deemed inoperable and treatment was palliative, the bleeding was successfully stopped with an endovascular aortic stent-graft. They both remained stable with no septic or hemorrhagic complications, and survived for 14 and 16 weeks after the operation. We emphasize that even if esophageal tumors are locally advanced, emergency endovascular management of aortoesophageal fistula is worthwhile for prolongation of survival.

scholarly journals Application of a simple device for "attracting" and "trapping" glioma cells in situ

2021 ◽  
Author(s):  
Haimin Song ◽  
Runwei Yang ◽  
Runbin Lai ◽  
Kaishu Li ◽  
Bowen Ni ◽  
...  
Keyword(s):  
Growth Factor ◽  
Tumor Cells ◽  
Adult Brain ◽  
Tumor Bed ◽  
In Vivo Experiments ◽  
New Strategy ◽  
New Treatment

Glioblastoma multiforme (GBM) is the most malignant adult brain tumor. The current adjuvant therapies for GBM are disappointing, which are based on cytotoxicity strategy. Thus, other ways should be explored to improve the curative effect. According to the strong invasive ability of GBM cells, we assume a new treatment strategy for GBM by developing a new cell trap device (CTD) with some kind of "attractive" medium loaded in it to attract and capture the tumor cells. The in vitro experiment showed that Hepatocyte Growth Factor（HGF）presented stronger chemotaxis on C6 and U87 cell line than the Epidermal Growth Factor (EGF) and Fibroblast Growth Factor (FGF). A simple in vitro CTD loaded with HGF was made and in vivo experiments results showed that HGF successfully attracted tumor cells from tumor bed in situ into the CTD. This study proposes the new strategy for GBM treatment of "attract and trap" tumor cells is proved to be feasible.

Ion-pair strategy for enabling amifostine oral absorption: Rat in situ and in vivo experiments

2013 ◽  
Vol 49 (4) ◽  
pp. 499-504 ◽  
Author(s):  
N. Samiei ◽  
V. Mangas-Sanjuan ◽  
I. González-Álvarez ◽  
M. Foroutan ◽  
A. Shafaati ◽  
...  
Keyword(s):  
Oral Absorption ◽  
Ion Pair ◽  
In Vivo Experiments

scholarly journals Conceptual Framework Development for a Double-Walled Aortic Stent-Graft to Manage Blood Pressure

2020 ◽  
Vol 14 (3) ◽  
Author(s):  
Shannen B. Kizilski ◽  
Omid Amili ◽  
Filippo Coletti ◽  
Rumi Faizer ◽  
Victor H. Barocas
Keyword(s):  
Stent Graft ◽  
Pulse Pressure ◽  
Fe Model ◽  
Flow Loop ◽  
Windkessel Model ◽  
Aortic Stent Graft ◽  
New Treatment ◽  
Gas Layer

Abstract A double-walled stent-graft (DWSG) design with a compressible gas layer was conceived with the goal of treating hypertension in patients receiving an aortic stent-graft. Early prototypes were developed to evaluate the design concept through static measurements from a finite element (FE) model and quasi-static inflation experiments, and through dynamic measurements from an in vitro flow loop and the three-element Windkessel model. The amount of gas in the gas layer and the properties of the flexible inner wall were the primary variables evaluated in this study. Properties of the inner wall had minimal effect on DWSG behavior, but increased gas charge led to increased fluid capacitance and larger reduction in peak and pulse pressures. In the flow loop, placement of the DWSG decreased pulse pressure by over 20% compared to a rigid stent-graft. Capacitance measurements were consistent across all methods, with the maximum capacitance estimated at 0.07 mL/mmHg for the largest gas charge in the 15 cm long prototype. Windkessel model predictions for in vivo performance of a DWSG placed in the aorta of a hypertensive patient showed pulse pressure reduction of 14% compared to a rigid stent-graft case, but pressures never returned to unstented values. These results indicate that the DWSG design has potential to be developed into a new treatment for hypertensive patients requiring an aortic intervention.

Computational modelling of maternal interactions with spermatozoa: potentials and prospects

2011 ◽  
Vol 23 (8) ◽  
pp. 976 ◽  
Author(s):  
Mark Burkitt ◽  
Dawn Walker ◽  
Daniela M. Romano ◽  
Alireza Fazeli
Keyword(s):  
Reproductive Tract ◽  
Computational Modelling ◽  
Female Reproductive Tract ◽  
In Vivo Experiments ◽  
Complex Interactions ◽  
Maternal Communication ◽  
In Silico Models

Understanding the complex interactions between gametes, embryos and the maternal tract is required knowledge for combating infertility and developing new methods of contraception. Here we present some main aspects of spermatozoa interactions with the mammalian oviduct before fertilisation and discuss how computational modelling can be used as an invaluable aid to experimental investigation in this field. A complete predictive computational model of gamete and embryo interactions with the female reproductive tract is a long way off. However, the enormity of this task should not discourage us from working towards it. Computational modelling allows us to investigate aspects of maternal communication with gametes and embryos, which are financially, ethically or practically difficult to look at experimentally. In silico models of maternal communication with gametes and embryos can be used as tools to complement in vivo experiments, in the same way as in vitro and in situ models.

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