Characterization of the ablation zones produced by three commercially available systems from a single vendor for radiofrequency thermoablation in an ex vivo swine liver model

Characterization of bladder biopsies, using a combined fiber optic probe-based optical coherence tomography and Raman spectroscopy imaging system that allows a large field-of-view imaging and detection and grading of cancerous bladder lesions.

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Consequences of SUR2[A478V] Mutation in Skeletal Muscle of Murine Model of Cantu Syndrome

Cells ◽

10.3390/cells10071791 ◽

2021 ◽

Vol 10 (7) ◽

pp. 1791

Author(s):

Rosa Scala ◽

Fatima Maqoud ◽

Nicola Zizzo ◽

Giuseppe Passantino ◽

Antonietta Mele ◽

...

Keyword(s):

Skeletal Muscle ◽

Katp Channel ◽

Ex Vivo ◽

Channel Modulation ◽

Flexor Digitorum Brevis ◽

Inflammatory Edema ◽

Flexor Digitorum ◽

Channel Currents

(1) Background: Cantu syndrome (CS) arises from gain-of-function (GOF) mutations in the ABCC9 and KCNJ8 genes, which encode ATP-sensitive K+ (KATP) channel subunits SUR2 and Kir6.1, respectively. Most CS patients have mutations in SUR2, the major component of skeletal muscle KATP, but the consequences of SUR2 GOF in skeletal muscle are unknown. (2) Methods: We performed in vivo and ex vivo characterization of skeletal muscle in heterozygous SUR2[A478V] (SUR2wt/AV) and homozygous SUR2[A478V] (SUR2AV/AV) CS mice. (3) Results: In SUR2wt/AV and SUR2AV/AV mice, forelimb strength and diaphragm amplitude movement were reduced; muscle echodensity was enhanced. KATP channel currents recorded in Flexor digitorum brevis fibers showed reduced MgATP-sensitivity in SUR2wt/AV, dramatically so in SUR2AV/AV mice; IC50 for MgATP inhibition of KATP currents were 1.9 ± 0.5 × 10−5 M in SUR2wt/AV and 8.6 ± 0.4 × 10−6 M in WT mice and was not measurable in SUR2AV/AV. A slight rightward shift of sensitivity to inhibition by glibenclamide was detected in SUR2AV/AV mice. Histopathological and qPCR analysis revealed atrophy of soleus and tibialis anterior muscles and up-regulation of atrogin-1 and MuRF1 mRNA in CS mice. (4) Conclusions: SUR2[A478V] “knock-in” mutation in mice impairs KATP channel modulation by MgATP, markedly so in SUR2AV/AV, with atrophy and non-inflammatory edema in different skeletal muscle phenotypes.

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Design of a force-measuring setup for colorectal compression anastomosis and first ex-vivo results

International Journal of Computer Assisted Radiology and Surgery ◽

10.1007/s11548-021-02371-8 ◽

2021 ◽

Author(s):

Jana Steger ◽

Isabella Patzke ◽

Maximilian Berlet ◽

Stefanie Ficht ◽

Markus Eblenkamp ◽

...

Keyword(s):

Ex Vivo ◽

Tissue Fixation ◽

Force Transmission ◽

Tissue Thickness ◽

Colon Tissue ◽

Device Development ◽

Compression Anastomosis ◽

Technical Requirements ◽

Significant Difference

Abstract Purpose The introduction of novel endoscopic instruments is essential to reduce trauma in visceral surgery. However, endoscopic device development is hampered by challenges in respecting the dimensional restrictions, due to the narrow access route, and by achieving adequate force transmission. As the overall goal of our research is the development of a patient adaptable, endoscopic anastomosis manipulator, biomechanical and size-related characterization of gastrointestinal organs are needed to determine technical requirements and thresholds to define functional design and load-compatible dimensioning of devices. Methods We built an experimental setup to measure colon tissue compression piercing forces. We tested 54 parameter sets, including variations of three tissue fixation configurations, three piercing body configurations (four, eight, twelve spikes) and insertion trajectories of constant velocities (5 mms−1, 10 mms−1,15 mms−1) and constant accelerations (5 mms−2, 10 mms−2, 15 mms−2) each in 5 samples. Furthermore, anatomical parameters (lumen diameter, tissue thickness) were recorded. Results There was no statistically significant difference in insertion forces neither between the trajectory groups, nor for variation of tissue fixation configurations. However, we observed a statistically significant increase in insertion forces for increasing number of spikes. The maximum mean peak forces for four, eight and twelve spikes were 6.4 ± 1.5 N, 13.6 ± 1.4 N and 21.7 ± 5.8 N, respectively. The 5th percentile of specimen lumen diameters and pierced tissue thickness were 24.1 mm and 2.8 mm, and the 95th percentiles 40.1 mm and 4.8 mm, respectively. Conclusion The setup enabled reliable biomechanical characterization of colon material, on the base of which design specifications for an endoscopic anastomosis device were derived. The axial implant closure unit must enable axial force transmission of at least 28 N (22 ± 6 N). Implant and applicator diameters must cover a range between 24 and 40 mm, and the implant gap, compressing anastomosed tissue, between 2 and 5 mm.

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Characterization of radical types, penetration profile and distribution pattern of the topically applied photosensitizer THPTS in porcine skin ex vivo

European Journal of Pharmaceutics and Biopharmaceutics ◽

10.1016/j.ejpb.2021.03.002 ◽

2021 ◽

Author(s):

Lohan SB ◽

Kröger M ◽

Schleusener J ◽

Darvin ME ◽

Lademann J ◽

...

Keyword(s):

Distribution Pattern ◽

Ex Vivo ◽

Porcine Skin ◽

Penetration Profile

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Characterization of Intrinsically Radiolabeled Poly(lactic-co-glycolic acid) Nanoparticles for ex Vivo Autologous Cell Labeling and in Vivo Tracking

Bioconjugate Chemistry ◽

10.1021/acs.bioconjchem.1c00271 ◽

2021 ◽

Author(s):

Massis Krekorian ◽

Gerwin G. W. Sandker ◽

Kimberley R. G. Cortenbach ◽

Oya Tagit ◽

N. Koen van Riessen ◽

...

Keyword(s):

Glycolic Acid ◽

Ex Vivo ◽

Cell Labeling ◽

Autologous Cell

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Author Correction: Feasibility, safety and accuracy of a CT-guided robotic assistance for percutaneous needle placement in a swine liver model

Scientific Reports ◽

10.1038/s41598-021-87093-2 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Boris Guiu ◽

Thierry De Baère ◽

Guillaume Noel ◽

Maxime Ronot

Keyword(s):

Robotic Assistance ◽

Needle Placement ◽

Ct Guided ◽

Liver Model ◽

Swine Liver

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

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About Puncture Testing Applied for Mechanical Characterization of Fetal Membranes

Journal of Biomechanical Engineering ◽

10.1115/1.4028446 ◽

2014 ◽

Vol 136 (11) ◽

Cited By ~ 6

Author(s):

Wilfried Bürzle ◽

Edoardo Mazza ◽

John J. Moore

Keyword(s):

Deformation Behavior ◽

Mechanical Characterization ◽

Ex Vivo ◽

Fetal Membrane ◽

Membrane Rupture ◽

Resistance To Deformation ◽

Ex Vivo Testing ◽

Insight Into

Puncture testing has been applied in several studies for the mechanical characterization of human fetal membrane (FM) tissue, and significant knowledge has been gained from these investigations. When comparing results of mechanical testing (puncture, inflation, and uniaxial tension), we have observed discrepancies in the rupture sequence of FM tissue and significant differences in the deformation behavior. This study was undertaken to clarify these discrepancies. Puncture experiments on FM samples were performed to reproduce previous findings, and numerical simulations were carried out to rationalize particular aspects of membrane failure. The results demonstrate that both rupture sequence and resistance to deformation depend on the samples' fixation. Soft fixation leads to slippage in the clamping, which reduces mechanical loading of the amnion layer and results in chorion rupturing first. Conversely, the stiffer, stronger, and less extensible amnion layer fails first if tight fixation is used. The results provide a novel insight into the interpretation of ex vivo testing as well as in vivo membrane rupture.

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Design and Characterization of Buccoadhesive Liquisolid System of an Antihypertensive Drug

Journal of Drug Delivery ◽

10.1155/2015/574247 ◽

2015 ◽

Vol 2015 ◽

pp. 1-9 ◽

Cited By ~ 1

Author(s):

Nilesh P. Kala ◽

Divyesh H. Shastri ◽

Pragna K. Shelat

Keyword(s):

Ex Vivo ◽

Flow Parameters ◽

Mucoadhesive Polymers ◽

Dissolution Properties ◽

Powder Characteristics ◽

Bioadhesive Polymers ◽

Tablet Formulations ◽

Permeability Studies ◽

Aluminium Silicate

Nifedipine is an antihypertensive BCS class II drug which has poor bioavailability when given orally. The objective of the present study was to increase the bioavailability of nifedipine, by formulation and evaluation of a buccoadhesive liquisolid system using magnesium aluminium silicate (Neusilin) as both carrier and coating material and dissolution media were selected based on the solubility studies. A mixture of carboxymethylcellulose sodium and carbomer was used as mucoadhesive polymers. Buccoadhesive tablets were prepared by direct compression. FTIR studies confirmed no interaction between drug and excipients. XRD studies indicated change/reduction in crystallinity of drug. The powder characteristics were evaluated by different flow parameters to comply with pharmacopoeial specifications. The dissolution studies for liquisolid compacts and tablet formulations were carried out and it was found that nifedipine liquisolid tablets formulated from bioadhesive polymers containing 49% liquisolid system, 17.5% carbomer, and 7.5% carboxymethylcellulose sodium showed the best results in terms of dissolution properties. Prepared formulation batches were evaluated for swelling, bioadhesion strength, ex vivo residence time, and permeability studies. The optimized batch was showing promising features of the system. Formulating nifedipine as a buccoadhesive tablet allows reduction in dose and offers better control over the plasma levels.

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