Design And In Vivo Testing of Novel Single-Stage Tendon Graft Using Polyurethane Nanocomposite Polymer for Tendon Reconstruction

Abstract Background Aspiration testing before filler injection is controversial. Some believe that aspiration can help prevent inadvertent intravascular injection, while others cite false-negative results and question its value given that the needle position always changes somewhat during injection procedures. Objectives To test the relation of false-negative results to the viscosity of the material within the needle lumen and determine whether a less viscous material within the needle lumen could decrease the incidence of false-negative results. Methods In vitro aspiration tests were performed using 30-G and 27-G needle gauges, two cross-linked hyaluronic acid fillers, normal saline bags pressurized at 140 and 10 mmHg to mimic human arterial and venous pressures, and three needle lumen conditions (normal saline, air, and filler). Testing was repeated three times under each study condition (72 tests in total). For in vivo correlation, aspiration tests were performed on femoral arteries and central auricular veins in three rabbits (4–5 aspirations per site, 48 tests in total). Results In vitro and in vivo testing using 30-G needles containing filler both showed false-negative results on aspiration testing. In vitro and in vivo testing using needles containing saline or air showed positive findings. Conclusions False-negative results from aspiration testing may be reduced by pre-filling the needle lumen with saline rather than a filler. The pressurized system may help overcome challenges of animal models with intravascular pressures significantly different from those of humans. The adaptability of this system to mimic various vessel pressures may facilitate physiologically relevant studies of vascular complications.

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Effective decellularisation of human saphenous veins for biocompatible arterial tissue engineering applications: Bench optimisation and feasibility in vivo testing

Journal of Tissue Engineering ◽

10.1177/2041731420987529 ◽

2021 ◽

Vol 12 ◽

pp. 204173142098752

Author(s):

Nadiah S Sulaiman ◽

Andrew R Bond ◽

Vito D Bruno ◽

John Joseph ◽

Jason L Johnson ◽

...

Keyword(s):

Tissue Engineering ◽

Mechanical Strength ◽

Vascular Tissue ◽

Sodium Dodecyl ◽

Host Cells ◽

Replacement Model ◽

In Vivo Testing ◽

Vascular Scaffolds

Human saphenous vein (hSV) and synthetic grafts are commonly used conduits in vascular grafting, despite high failure rates. Decellularising hSVs (D-hSVs) to produce vascular scaffolds might be an effective alternative. We assessed the effectiveness of a detergent-based method using 0% to 1% sodium dodecyl sulphate (SDS) to decellularise hSV. Decellularisation effectiveness was measured in vitro by nuclear counting, DNA content, residual cell viability, extracellular matrix integrity and mechanical strength. Cytotoxicity was assessed on human and porcine cells. The most effective SDS concentration was used to prepare D-hSV grafts that underwent preliminary in vivo testing using a porcine carotid artery replacement model. Effective decellularisation was achieved with 0.01% SDS, and D-hSVs were biocompatible after seeding. In vivo xeno-transplantation confirmed excellent mechanical strength and biocompatibility with recruitment of host cells without mechanical failure, and a 50% patency rate at 4-weeks. We have developed a simple biocompatible methodology to effectively decellularise hSVs. This could enhance vascular tissue engineering toward future clinical applications.

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In vivo testing of the low-flow CO2 removal application of a compact, platform respiratory device

Intensive Care Medicine Experimental ◽

10.1186/s40635-020-00329-9 ◽

2020 ◽

Vol 8 (1) ◽

Author(s):

Alexandra G. May ◽

Ryan A. Orizondo ◽

Brian J. Frankowski ◽

Sang-Ho Ye ◽

Ergin Kocyildirim ◽

...

Keyword(s):

Low Flow ◽

Co2 Removal ◽

In Vivo Testing

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Whither Magnetic Hyperthermia? A Tentative Roadmap

Materials ◽

10.3390/ma14040706 ◽

2021 ◽

Vol 14 (4) ◽

pp. 706

Author(s):

Irene Rubia-Rodríguez ◽

Antonio Santana-Otero ◽

Simo Spassov ◽

Etelka Tombácz ◽

Christer Johansson ◽

...

Keyword(s):

Clinical Trials ◽

Nanoparticle Synthesis ◽

Careful Analysis ◽

Magnetic Hyperthermia ◽

Lessons Learned ◽

In Vivo Testing ◽

Evolution Of Science ◽

Made In ◽

Critical Aspects

The scientific community has made great efforts in advancing magnetic hyperthermia for the last two decades after going through a sizeable research lapse from its establishment. All the progress made in various topics ranging from nanoparticle synthesis to biocompatibilization and in vivo testing have been seeking to push the forefront towards some new clinical trials. As many, they did not go at the expected pace. Today, fruitful international cooperation and the wisdom gain after a careful analysis of the lessons learned from seminal clinical trials allow us to have a future with better guarantees for a more definitive takeoff of this genuine nanotherapy against cancer. Deliberately giving prominence to a number of critical aspects, this opinion review offers a blend of state-of-the-art hints and glimpses into the future of the therapy, considering the expected evolution of science and technology behind magnetic hyperthermia.

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The identification of novel immunogenic antigens as potential Shigella vaccine components

Genome Medicine ◽

10.1186/s13073-020-00824-4 ◽

2021 ◽

Vol 13 (1) ◽

Author(s):

Ruklanthi de Alwis ◽

Li Liang ◽

Omid Taghavian ◽

Emma Werner ◽

Hao Chung The ◽

...

Keyword(s):

Core Genome ◽

Genomic Analysis ◽

Carrier Proteins ◽

Vaccine Candidates ◽

Vaccine Antigens ◽

Bactericidal Antibody ◽

In Vivo Testing ◽

Species Specific ◽

Selection Of

Abstract Background Shigella is a major diarrheal pathogen for which there is presently no vaccine. Whole genome sequencing provides the ability to predict and derive novel antigens for use as vaccines. Here, we aimed to identify novel immunogenic Shigella antigens that could serve as Shigella vaccine candidates, either alone, or when conjugated to Shigella O-antigen. Methods Using a reverse vaccinology approach, where genomic analysis informed the Shigella immunome via an antigen microarray, we aimed to identify novel immunogenic Shigella antigens. A core genome analysis of Shigella species, pathogenic and non-pathogenic Escherichia coli, led to the selection of 234 predicted immunogenic Shigella antigens. These antigens were expressed and probed with acute and convalescent serum from microbiologically confirmed Shigella infections. Results Several Shigella antigens displayed IgG and IgA seroconversion, with no difference in sero-reactivity across by sex or age. IgG sero-reactivity to key Shigella antigens was observed at birth, indicating transplacental antibody transfer. Six antigens (FepA, EmrK, FhuA, MdtA, NlpB, and CjrA) were identified in in vivo testing as capable of producing binding IgG and complement-mediated bactericidal antibody. Conclusions These findings provide six novel immunogenic Shigella proteins that could serve as candidate vaccine antigens, species-specific carrier proteins, or targeted adjuvants.

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Optimized 5-Fluorouridine Prodrug for Co-Loading with Doxorubicin in Clinically Relevant Liposomes

Pharmaceutics ◽

10.3390/pharmaceutics13010107 ◽

2021 ◽

Vol 13 (1) ◽

pp. 107

Author(s):

Debra Wu ◽

Douglas Vogus ◽

Vinu Krishnan ◽

Marta Broto ◽

Anusha Pusuluri ◽

...

Keyword(s):

Single Agent ◽

Molar Ratio ◽

Control Group ◽

Drug Tolerability ◽

Breast Cancer Model ◽

In Vivo Testing ◽

Chemical Profiles ◽

Hydrolysis Of ◽

Doxorubicin Liposomes

Liposome-based drug delivery systems have allowed for better drug tolerability and longer circulation times but are often optimized for a single agent due to the inherent difficulty of co-encapsulating two drugs with differing chemical profiles. Here, we design and test a prodrug based on a ribosylated nucleoside form of 5-fluorouracil, 5-fluorouridine (5FUR), with the final purpose of co-encapsulation with doxorubicin (DOX) in liposomes. To improve the loading of 5FUR, we developed two 5FUR prodrugs that involved the conjugation of either one or three moieties of tryptophan (W) known respectively as, 5FUR−W and 5FUR−W3. 5FUR−W demonstrated greater chemical stability than 5FUR−W3 and allowed for improved loading with fewer possible byproducts from tryptophan hydrolysis. Varied drug ratios of 5FUR−W: DOX were encapsulated for in vivo testing in the highly aggressive 4T1 murine breast cancer model. A liposomal molar ratio of 2.5 5FUR−W: DOX achieved a 62.6% reduction in tumor size compared to the untreated control group and a 33% reduction compared to clinical doxorubicin liposomes in a proof-of-concept study to demonstrate the viability of the co-encapsulated liposomes. We believe that the new prodrug 5FUR−W demonstrates a prodrug design with clinical translatability by reducing the number of byproducts produced by the hydrolysis of tryptophan, while also allowing for loading flexibility.

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DDEL-12. NANOPARTICLE DELIVERY OF DOXORUBICIN FOR THE TREATMENT OF DIFFUSE INTRINSIC PONTINE GLIOMA (DIPG)

Neuro-Oncology ◽

10.1093/neuonc/noaa222.047 ◽

2020 ◽

Vol 22 (Supplement_3) ◽

pp. iii286-iii286

Author(s):

Caitlin Ung ◽

Maria Tsoli ◽

Jie Liu ◽

Domenico Cassano ◽

Dannielle Upton ◽

...

Keyword(s):

Treatment Strategies ◽

Pediatric Brain Tumors ◽

Diffuse Intrinsic Pontine Glioma ◽

Confocal Imaging ◽

Cell Content ◽

Potent Effect ◽

Orthotopic Mouse Model ◽

In Vivo Testing

Abstract DIPGs are the most aggressive pediatric brain tumors. Currently, the only treatment is irradiation but due to its palliative nature patients die within 12 months. Effective delivery of chemotherapy across the blood-brain barrier (BBB) has been a key challenge for the eradication of this disease. We have developed a novel gold nanoparticle functionalised with human serum albumin (Au-NP, 98.8 ±19 nm) for the delivery of doxorubicin. In this study, we evaluated the cytotoxic efficacy of doxorubicin delivered through gold nanoparticles (Au-NP-Dox). We found that DIPG neurospheres were equally sensitive to doxorubicin and Au-NP-Dox (at equimolar concentration) by alamar blue assay. Colony formation assays demonstrated a significantly more potent effect of Au-NP-Dox compared to doxorubicin alone, while the Au-NP had no effect. Furthermore, western blot analysis indicated increased apoptotic markers cleaved Parp, caspase 3/7 and phosphorylated H2AX in Au-NP-Dox treated DIPG neurospheres. Live cell content and confocal imaging demonstrated significantly higher uptake of Au-NP-Dox compared to doxorubicin alone. Treatment of a DIPG orthotopic mouse model with Au-NP-Dox showed no signs of toxicity with stable weights being maintained during treatment. However, in contrast to the above in vitro findings the in vivo study showed no anti-tumor effect possibly due to poor penetration of Au-NP-Dox into the brain. We are currently evaluating whether efficacy can be improved using measures to open the BBB transiently. This study highlights the need for rigorous in vivo testing of new treatment strategies before clinical translation to reduce the risk of administration of ineffective treatments.

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