First In Vivo Test of Thermoembolization: Turning Tissue Against Itself Using Transcatheter Chemistry in a Porcine Model

SummaryDefibrotide is a polydeoxyribonucleotide with antithrombotic effects in experimental animal models. Most of the actions of this drug have been observed in in vivo test models but no effects have been reported in in vitro systems. In this paper we demonstrate that defibrotide interferes with polymorphonuclear leukocyte-induced human platelet activation in vitro. This effect was not related to any direct interaction with polymorphonuclear leukocytes or platelets, but was due to the inhibition of cathepsin G, the main biochemical mediator of this cell-cell cooperation. Since cathepsin G not only induces platelet activation but also affects some endothelial cell functions, the anticathepsin G activity of defibrotide could help to explain the antithrombotic effect of this drug.

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Comparative Evaluation of In Vitro and In Vivo Assays for the Detection of Avian Infectious Bronchitis Virus as a Contaminant of Live Poultry Vaccines

Alternatives to Laboratory Animals ◽

10.1177/026119299802600508 ◽

1998 ◽

Vol 26 (5) ◽

pp. 629-634

Author(s):

Emiliana Falcone ◽

Edoardo Vignolo ◽

Livia Di Trani ◽

Simona Puzelli ◽

Maria Tollis

Keyword(s):

Infectious Bronchitis Virus ◽

Serological Response ◽

Avian Infectious Bronchitis Virus ◽

Animal Testing ◽

Rt Pcr ◽

Pcr Assay ◽

In Vivo Test ◽

Infectious Bronchitis

A reverse transcriptase polymerase chain reaction (RT-PCR) assay specific for identifying avian infectious bronchitis virus (IBV) in poultry vaccines, and the serological response to IBV induced by the inoculation of chicks with a Newcastle disease vaccine spiked with the Massachusetts strain of IBV, were compared for their ability to detect IBV as a contaminant of avian vaccines. The sensitivity of the IBV-RT-PCR assay provided results which were at least equivalent to the biological effect produced by the inoculation of chicks, allowing this assay to be considered a valid alternative to animal testing in the quality control of avian immunologicals. This procedure can easily be adapted to detect a number of contaminants for which the in vivo test still represents the only available method of detection.

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Wafer-Scale Fabrication and Assembly Method of Multichannel Microelectrode Arrays for ECoG Application

Electronics ◽

10.3390/electronics10030316 ◽

2021 ◽

Vol 10 (3) ◽

pp. 316

Author(s):

Cong Wang ◽

Yu-Chen Wei ◽

Ho-Kun Sung ◽

Alok Kumar ◽

Zhong-Liang Zhou ◽

...

Keyword(s):

Printed Circuit Boards ◽

Electrochemical Impedance ◽

Microelectrode Arrays ◽

Absence Seizure ◽

Curing Conditions ◽

Wafer Scale ◽

In Vivo Test ◽

Assembly Method ◽

Signal Recording

High density electrocorticography (ECoG)-based microelectrode arrays (MEAs) are fabricated to timely record the neural activities to provide the fundamental understanding in neuroscience and biomedical engineering. This paper aims to introduce a device-based concept and wafer-scale fabrication process for MEAs. Flexible and biocompatible polyimide is applied on MEAs to bear all possible stress and strain. Detailed fabrication key techniques, including surface treatment, polyimide stability measurement, evaporation process, and curing conditions, have been discussed thoroughly. Moreover, the fabricated polyimide-based MEAs are surface-mounted on well-packaged printed circuit boards (PCBs) via a slot-type connector without any additional wire bonding to make the signal recording process easier. An absence seizure was recorded during the in vivo test, which shows the availability of signal recording based on the presented MEAs. The proposed MEAs could be remained at the skull, while the connector and PCBs can be disassembled apart. Therefore, the testing sample will get less suffering. To verify the robustness of the fabricated MEAs, the impedance properties were characterized using electrochemical impedance spectroscopy. The measured results indicate an average impedance of 12.3 ± 0.675 kΩ at 1 kHz. In total, 10 groups of MEAs were sample tested, and over 90% of the total 60 channels per 1-MEAs operated efficiently.

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Preclinical Testing of Radiopharmaceuticals for the Detection and Characterization of Osteomyelitis: Experiences from a Porcine Model

Molecules ◽

10.3390/molecules26144221 ◽

2021 ◽

Vol 26 (14) ◽

pp. 4221

Author(s):

Aage Kristian Olsen Alstrup ◽

Svend Borup Jensen ◽

Ole Lerberg Nielsen ◽

Lars Jødal ◽

Pia Afzelius

Keyword(s):

Animal Model ◽

Animal Models ◽

Porcine Model ◽

Animal Experiments ◽

Radioactive Tracers ◽

The Individual ◽

Selection Of

The development of new and better radioactive tracers capable of detecting and characterizing osteomyelitis is an ongoing process, mainly because available tracers lack selectivity towards osteomyelitis. An integrated part of developing new tracers is the performance of in vivo tests using appropriate animal models. The available animal models for osteomyelitis are also far from ideal. Therefore, developing improved animal osteomyelitis models is as important as developing new radioactive tracers. We recently published a review on radioactive tracers. In this review, we only present and discuss osteomyelitis models. Three ethical aspects (3R) are essential when exposing experimental animals to infections. Thus, we should perform experiments in vitro rather than in vivo (Replacement), use as few animals as possible (Reduction), and impose as little pain on the animal as possible (Refinement). The gain for humans should by far exceed the disadvantages for the individual experimental animal. To this end, the translational value of animal experiments is crucial. We therefore need a robust and well-characterized animal model to evaluate new osteomyelitis tracers to be sure that unpredicted variation in the animal model does not lead to a misinterpretation of the tracer behavior. In this review, we focus on how the development of radioactive tracers relies heavily on the selection of a reliable animal model, and we base the discussions on our own experience with a porcine model.

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Strong Antimicrobial and Healing Effects of Beta-Acids from Hops in Methicillin-Resistant Staphylococcus aureus-Infected External Wounds In Vivo

Antibiotics ◽

10.3390/antibiotics10060708 ◽

2021 ◽

Vol 10 (6) ◽

pp. 708

Author(s):

Radek Sleha ◽

Vera Radochova ◽

Jiri Malis ◽

Alexander Mikyska ◽

Milan Houska ◽

...

Keyword(s):

Wound Healing ◽

Porcine Model ◽

Therapeutic Effects ◽

Methicillin Resistant ◽

Antimicrobial Effects ◽

Therapeutic Modalities ◽

Positive Effects ◽

Inflammatory Parameters

Staphylococcus (S.) aureus is an important causative agent of wound infections with increasing incidence in the past decades. Specifically, the emergence of methicillin-resistant S. aureus (MRSA) causes serious problems, especially in nosocomial infections. Therefore, there is an urgent need to develop of alternative or supportive antimicrobial therapeutic modalities to meet these challenges. Purified compounds from hops have previously shown promising antimicrobial effects against MRSA isolates in vitro. In this study, purified beta-acids from hops were tested for their potential antimicrobial and healing properties using a porcine model of wounds infected by MRSA. The results show highly significant antimicrobial effects of the active substance in both the powder and Ambiderman-based application forms compared to both no-treatment control and treatment with Framycoin. Moreover, the macroscopic evaluation of the wounds during the treatment using the standardized Wound Healing Continuum indicated positive effects of the beta-acids on the overall wound healing. This is further supported by the microscopic data, which showed a clear improvement of the inflammatory parameters in the wounds treated by beta-acids. Thus, using the porcine model, we demonstrate significant therapeutic effects of hops compounds in the management of wounds infected by MRSA. Beta-acids from hops, therefore, represent a suitable candidate for the treatment of non-responsive nosocomial tissue infections by MRSA.

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Development of a gel dedicated to gel immersion endoscopy

Endoscopy International Open ◽

10.1055/a-1396-4236 ◽

2021 ◽

Vol 09 (06) ◽

pp. E918-E924

Author(s):

Tomonori Yano ◽

Atsushi Ohata ◽

Yuji Hiraki ◽

Makoto Tanaka ◽

Satoshi Shinozaki ◽

...

Keyword(s):

Electrical Conductivity ◽

Porcine Model ◽

Ex Vivo ◽

In Vitro Experiments ◽

Efficacy And Safety ◽

Coagulative Necrosis ◽

Novel Technique ◽

In Vivo Experiments

Abstract Backgrounds and study aims Gel immersion endoscopy is a novel technique to secure the visual field during endoscopy. The aim of this study was to develop a dedicated gel for this technique. Methods To identify appropriate viscoelasticity and electrical conductivity, various gels were examined. Based on these results, the dedicated gel “OPF-203” was developed. Efficacy and safety of OPF-203 were evaluated in a porcine model. Results In vitro experiments showed that a viscosity of 230 to 1900 mPa·s, loss tangent (tanδ) ≤ 0.6, and hardness of 240 to 540 N/cm2 were suitable. Ex vivo experiments showed electrical conductivity ≤ 220 μS/cm is appropriate. In vivo experiments using gastrointestinal bleeding showed that OPF-203 provided clear visualization compared to water. After electrocoagulation of gastric mucosa in OPF-203, severe coagulative necrosis was not observed in the muscularis but limited to the mucosa. Conclusions OPF-203 is useful for gel immersion endoscopy.

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Defect structures of sodium and chloride co-substituted hydroxyapatite and its osseointegration capacity

Journal of Materials Science ◽

10.1007/s10853-020-05645-9 ◽

2021 ◽

Vol 56 (9) ◽

pp. 5493-5508

Author(s):

Dong Su Yoo ◽

Jung Sang Cho ◽

Yong-Chae Chung ◽

Sang-Hoon Rhee

Keyword(s):

Binding Energies ◽

Dissolution Behavior ◽

Total System ◽

Carbonate Apatite ◽

In Vivo Test ◽

Co Substitution ◽

Constituent Elements ◽

Low Crystalline ◽

Charged Point

AbstractA defect structure and osseointegration capacity of sodium and chloride co-substituted hydroxyapatite (NaClAp) were newly studied. The NaClAp was prepared by reacting H3PO4 and Ca(OH)2 with NaNO3 and NH4Cl followed by sintering; pure hydroxyapatite (HAp) was synthesized as a control. After sintering, the co-substitution of Ca and OH with Na and Cl, respectively, produced charged point defects at Ca and PO4 sites. Also, OH molecules partially adopted a head-on structure. The calculated total system energy of NaClAp was higher, whereas the binding energies between each constituent elements and system were lower than those of HAp. These results suggest that NaClAp was less stable than HAp, due to the formation of various defects by co-substitution of Na and Cl. Indeed, NaClAp exhibited higher dissolution behavior in simulated body fluid (SBF) compared with HAp. Accordingly, this increased the capability to produce low crystalline hydroxyl carbonate apatite, likely due to the increasing degree of apatite supersaturation in SBF. Besides, the NaClAp granules showed noticeable improvements in osseointegration capacity four weeks after in vivo test compared with HAp. Collectively, these results imply that the defects made by multiple ion substitutions are useful to increase osseointegration capacity of hydroxyapatite.

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Dynamic Quantitative Iodine Myocardial Perfusion Imaging with Dual-Layer CT using a Porcine Model

Scientific Reports ◽

10.1038/s41598-019-52458-1 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 2

Author(s):

Kai Scherer ◽

Johannes Hammel ◽

Thorsten Sellerer ◽

Korbinian Mechlem ◽

Bernhard Renger ◽

...

Keyword(s):

Contrast Agent ◽

Perfusion Imaging ◽

Porcine Model ◽

Ct Perfusion ◽

Dual Energy Ct ◽

Beam Hardening ◽

Low Contrast ◽

Time To Peak ◽

Coronary Ct

Abstract Ischemic heart disease is the globally leading cause of death. When using coronary CT angiography, the functional hemodynamics within the myocardium remain uncertain. In this study myocardial CT perfusion imaging using iodine contrast agent demonstrated to strongly improve the assessment of myocardial disorders. However, a retrieval of such dynamics using Hounsfield units from conventional CT poses concerns with respect to beam-hardening effects and low contrast-to-noise ratio (CNR). Dual-energy CT offers novel approaches to overcome aforementioned limitations. Quantitative peak enhancement, perfusion, time to peak and iodine volume measurements inside the myocardium were determined resulting in 0.92 mg/ml, 0.085 mg/ml/s 17.12 s and 29.89 mg/ml*s, respectively. We report on the first extensive quantitative and iodine-based analysis of myocardial dynamics in a healthy porcine model using a dual-layer spectral CT. We further elucidate on the potential of reducing the radiation dose from 135 to 18 mGy and the contrast agent volume from 60 to 30 mL by presenting a two-shot acquisition approach and measuring iodine concentrations in the myocardium in-vivo down to 1 mg/ml, respectively. We believe that dynamic quantitative iodine perfusion imaging may be a highly sensitive tool for the precise functional assessment and monitoring of early myocardial ischemia.

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