In-vivo DEXA in large animal models: Does animal anatomy and positioning hold the clinical standards?

2017 ◽  
Vol 05 (01) ◽  
Author(s):  
Deeksha Malhan ◽  
Thaqif El Khassawna ◽  
Christian Heiss
Keyword(s):  
Animal Models ◽  
Large Animal ◽  
Clinical Standards ◽  
Large Animal Models ◽  
Animal Anatomy

scholarly journals Review: Tissue Engineering of Small-Diameter Vascular Grafts and Their In Vivo Evaluation in Large Animals and Humans

Cells ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 713
Author(s):  
Shu Fang ◽  
Ditte Gry Ellman ◽  
Ditte Caroline Andersen
Keyword(s):  
Animal Models ◽  
Vascular Grafts ◽  
Small Diameter ◽  
Large Animal ◽  
Large Animal Models ◽  
Graft Outcome ◽  
Limited Success ◽  
Large Animals

To date, a wide range of materials, from synthetic to natural or a mixture of these, has been explored, modified, and examined as small-diameter tissue-engineered vascular grafts (SD-TEVGs) for tissue regeneration either in vitro or in vivo. However, very limited success has been achieved due to mechanical failure, thrombogenicity or intimal hyperplasia, and improvements of the SD-TEVG design are thus required. Here, in vivo studies investigating novel and relative long (10 times of the inner diameter) SD-TEVGs in large animal models and humans are identified and discussed, with emphasis on graft outcome based on model- and graft-related conditions. Only a few types of synthetic polymer-based SD-TEVGs have been evaluated in large-animal models and reflect limited success. However, some polymers, such as polycaprolactone (PCL), show favorable biocompatibility and potential to be further modified and improved in the form of hybrid grafts. Natural polymer- and cell-secreted extracellular matrix (ECM)-based SD-TEVGs tested in large animals still fail due to a weak strength or thrombogenicity. Similarly, native ECM-based SD-TEVGs and in-vitro-developed hybrid SD-TEVGs that contain xenogeneic molecules or matrix seem related to a harmful graft outcome. In contrast, allogeneic native ECM-based SD-TEVGs, in-vitro-developed hybrid SD-TEVGs with allogeneic banked human cells or isolated autologous stem cells, and in-body tissue architecture (IBTA)-based SD-TEVGs seem to be promising for the future, since they are suitable in dimension, mechanical strength, biocompatibility, and availability.

scholarly journals Consequences of mitral valve prolapse on chordal tension: Ex vivo and in vivo studies in large animal models

2011 ◽  
Vol 142 (6) ◽  
pp. 1585-1587 ◽  
Author(s):  
Mathieu Granier ◽  
Morten O. Jensen ◽  
Jesper L. Honge ◽  
Alain Bel ◽  
Philippe Menasché ◽  
...  
Keyword(s):  
Mitral Valve ◽  
Animal Models ◽  
Mitral Valve Prolapse ◽  
Ex Vivo ◽  
In Vivo Studies ◽  
Large Animal ◽  
Large Animal Models

scholarly journals Adult Canine Intestinal Derived Organoids: A Novel In Vitro System for Translational Research in Comparative Gastroenterology

2018 ◽  
Author(s):  
Lawrance Chandra ◽  
Dana C Borcherding ◽  
Dawn Kingsbury ◽  
Todd Atherly ◽  
Yoko M Ambrosini ◽  
...  
Keyword(s):  
Animal Models ◽  
Translational Research ◽  
Three Dimensional ◽  
Metabolic Imaging ◽  
Large Animal ◽  
Large Animal Models ◽  
Molecular Features ◽  
Naturally Occurring

AbstractBackgroundLarge animal models, such as the dog, are increasingly being used over rodent models for studying naturally occurring diseases including gastrointestinal (GI) disorders. Dogs share similar environmental, genomic, anatomical, and intestinal physiologic features with humans. To bridge the gap between currently used animal models (e.g. mouse) and humans, and expand the translational potential of the dog model, we developed a three dimensional (3D) canine GI organoid (enteroid and colonoid) system. Organoids have recently gained interest in translational research as this model system better recapitulates the physiological and molecular features of the tissue environment in comparison with two-dimensional cultures.ResultsOrganoids were propagated from isolation of adult intestinal stem cells (ISC) from whole jejunal tissue as well as endoscopically obtained duodenal, ileal and colonic biopsy samples of healthy dogs and GI cases, including inflammatory bowel disease (IBD) and intestinal carcinomas. Intestinal organoids were comprehensively characterized using histology, immunohistochemistry, RNA in situ hybridization and transmission electron microscopy, and organoids mimicked the in vivo tissue environment. Physiological relevance of the enteroid system was defined using functional assays such as Optical Metabolic Imaging (OMI), the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) function assay, and Exosome-Like Vesicles (EV) uptake assay, as a basis for wider applications of this technology in basic, preclinical and translational GI research.ConclusionsIn summary, our findings establish the canine GI organoid systems as a novel model to study naturally occurring intestinal diseases in dogs and humans. Furthermore, canine organoid systems will help to elucidate host-pathogen interactions contributing to GI disease pathogenesis.

scholarly journals Large Animal Models of an In Vivo Bioreactor for Engineering Vascularized Bone

2018 ◽  
Vol 24 (4) ◽  
pp. 317-325 ◽  
Author(s):  
Banu Akar ◽  
Alexander M. Tatara ◽  
Alok Sutradhar ◽  
Hui-Yi Hsiao ◽  
Michael Miller ◽  
...  
Keyword(s):  
Animal Models ◽  
Large Animal ◽  
Large Animal Models ◽  
Vascularized Bone

scholarly journals Charge-switchable polymeric complex for glucose-responsive insulin delivery in mice and pigs

2019 ◽  
Vol 5 (7) ◽  
pp. eaaw4357 ◽  
Author(s):  
Jinqiang Wang ◽  
Jicheng Yu ◽  
Yuqi Zhang ◽  
Xudong Zhang ◽  
Anna R. Kahkoska ◽  
...  
Keyword(s):  
Animal Models ◽  
Insulin Release ◽  
Phenylboronic Acid ◽  
Insulin Delivery ◽  
Fast Response ◽  
Diabetic Mouse ◽  
Glucose Sensing ◽  
Large Animal ◽  
Large Animal Models

Glucose-responsive insulin delivery systems with robust responsiveness that has been validated in animal models, especially in large animal models, remain elusive. Here, we exploit a new strategy to form a micro-sized complex between a charge-switchable polymer with a glucose-sensing moiety and insulin driven by electrostatic interaction. Both high insulin loading efficiency (95%) and loading capacity (49%) can be achieved. In the presence of a hyperglycemic state, the glucose-responsive phenylboronic acid (PBA) binds glucose instantly and converts the charge of the polymeric moiety from positive to negative, thereby enabling the release of insulin from the complex. Adjusting the ratio of the positively charged group to PBA achieves inhibited insulin release from the complex under normoglycemic conditions and promoted release under hyperglycemic conditions. Through chemically induced type 1 diabetic mouse and swine models, in vivo hyperglycemia-triggered insulin release with fast response is demonstrated after the complex is administrated by either subcutaneous injection or transdermal microneedle array patch.

scholarly journals iPSC Therapy for Myocardial Infarction in Large Animal Models: Land of Hope and Dreams

Biomedicines ◽  
2021 ◽  
Vol 9 (12) ◽  
pp. 1836
Author(s):  
Daina Martínez-Falguera ◽  
Oriol Iborra-Egea ◽  
Carolina Gálvez-Montón
Keyword(s):  
Myocardial Infarction ◽  
Animal Models ◽  
Therapeutic Potential ◽  
Cell Types ◽  
Large Animal ◽  
Technical Application ◽  
In Vivo Models ◽  
Large Animal Models ◽  
Induced Pluripotent

Myocardial infarction is the main driver of heart failure due to ischemia and subsequent cell death, and cell-based strategies have emerged as promising therapeutic methods to replace dead tissue in cardiovascular diseases. Research in this field has been dramatically advanced by the development of laboratory-induced pluripotent stem cells (iPSCs) that harbor the capability to become any cell type. Like other experimental strategies, stem cell therapy must meet multiple requirements before reaching the clinical trial phase, and in vivo models are indispensable for ensuring the safety of such novel therapies. Specifically, translational studies in large animal models are necessary to fully evaluate the therapeutic potential of this approach; to empirically determine the optimal combination of cell types, supplementary factors, and delivery methods to maximize efficacy; and to stringently assess safety. In the present review, we summarize the main strategies employed to generate iPSCs and differentiate them into cardiomyocytes in large animal species; the most critical differences between using small versus large animal models for cardiovascular studies; and the strategies that have been pursued regarding implanted cells’ stage of differentiation, origin, and technical application.

scholarly journals Cardiac metabolic imaging using hyperpolarized [1-13C]lactate as a substrate

2020 ◽  
Author(s):  
Angus Z Lau ◽  
Albert P Chen ◽  
Charles H Cunningham
Keyword(s):  
Animal Models ◽  
Small Animal ◽  
Cardiac Metabolism ◽  
Metabolic Imaging ◽  
Attractive Alternative ◽  
Similar Degree ◽  
Large Animal ◽  
Large Animal Models ◽  
Similar Appearance

AbstractHyperpolarized [1-13C]lactate is an attractive alternative to [1-13C]pyruvate as a substrate to investigate cardiac metabolism in vivo; it can be administered safely at a higher dose and can be polarized to a similar degree as pyruvate via dynamic nuclear polarization. While 13C cardiac experiments using HP lactate have been performed in small animal models, it has not been demonstrated in large animal models or humans. Utilizing the same hardware and data acquisition methods used in the first human HP 13C cardiac study, 13C metabolic images were acquired following injections of HP [1-13C]lactate in porcine hearts. Data were also acquired using HP [1-13C]pyruvate for comparison. The 13C bicarbonate signal was localized to the myocardium and had a similar appearance with both substrates for all animals. No 13C pyruvate signal was detected in the experiments following injection of hyperpolarized 13C lactate. The SNR of injected lactate was 88 +/-14% of the SNR of injected pyruvate, and the SNR of bicarbonate in the experiments using lactate as the substrate was 52+/-19% of the SNR in the experiments using pyruvate as the substrate. The lower SNR was likely due to the shorter T1 of [1-13C]lactate as compared to [1-13C]pyruvate and the additional enzyme-catalyzed metabolic conversion step before the 13C nuclei from [1-13C]lactate were detected as 13C bicarbonate. While challenges remain, the potential of HP lactate as a substrate for clinical metabolic imaging of human heart was demonstrated.

scholarly journals In vivo imaging system for explants analysis—A new approach for assessment of cell transplantation effects in large animal models

PLoS ONE ◽  
2017 ◽  
Vol 12 (9) ◽  
pp. e0184588 ◽  
Author(s):  
Weronika Zarychta-Wiśniewska ◽  
Anna Burdzinska ◽  
Radosław Zagozdzon ◽  
Bartosz Dybowski ◽  
Marta Butrym ◽  
...  
Keyword(s):  
Animal Models ◽  
Cell Transplantation ◽  
In Vivo Imaging ◽  
Imaging System ◽  
Large Animal ◽  
New Approach ◽  
Large Animal Models ◽  
In Vivo Imaging System
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