successful-orthotopic-liver-transplantation-mice-utilizing

Successful Orthotopic Liver Transplantation in Mice Utilizing Microcomputed Tomography Angiography

Microcomputed tomography (microCT) angiography is an invaluable resource to researchers. New advances in this technology have allowed for high-quality ...

The Ohio State University

Breast cancer resistance to therapy can result from expression of antiapoptotic genes. Survivin is an antiapoptotic gene that is over expressed in most human tumors. RNA interference using short interfering RNA (siRNA) can be used to specifically inhibit survivin expression. A novel siRNA targeting survivin was used to process MCF-7 cells. Cellular survivin mRNA and protein levels were determined by real-time qRT-PCR and Western blot, respectively. Cellular morphology and cell cycle were determined by fluorescence microscopy and flow cytometry. Cell proliferation was measured by MTT assay. Our data showed that the novel survivin-targeted siRNA could efficiently knockdown the expression of survivin, inhibit cell proliferation and cell cycle, especially at the G2/M checkpoint. These data suggest that the siRNA has potential for therapeutic applications.

Antitumor activity of a novel survivin siRNA.

Stem-cell therapy has the potential to regenerate damaged heart tissue after a heart attack. Injectable hydrogels may be used as stem-cell carriers to improve cell retention in the heart tissue. However, current hydrogels are not ideal to serve as cell carriers because most of them block blood vessels after solidification. In addition, these hydrogels have a relatively slow gelation rate (typically >60 s), which does not allow them to quickly solidify upon injection, so as to efficiently hold cells in the heart tissue. As a result, the hydrogels and cells are squeezed out of the tissue, leading to low cell retention. To address these issues, we have developed hydrogels that can quickly solidify at the pH of an infarcted heart (6-7) at 37 °C but cannot solidify at the pH of blood (7.4) at 37 °C. These hydrogels are also clinically attractive because they can be injected through catheters commonly used for minimally invasive surgeries. The hydrogels were synthesized by free-radical polymerization of N-isopropylacrylamide, propylacrylic acid, hydroxyethyl methacrylate-co-oligo(trimethylene carbonate), and methacrylate poly(ethylene oxide) methoxy ester. Hydrogel solutions were injectable through 0.2-mm-diameter catheters at pH 8.0 at 37 °C, and they can quickly form solid gels under pH 6.5 at 37 °C. All of the hydrogels showed pH-dependent degradation and mechanical properties with less mass loss and greater complex shear modulus at pH 6.5 than at pH 7.4. When cardiosphere-derived cells (CDCs) were encapsulated in the hydrogels, the cells were able to survive during a 7-day culture period. The surviving cells were differentiated into cardiac cells, as evidenced by the expression of cardiac markers at both the gene and protein levels, such as cardiac troponin T, myosin heavy chain α, calcium channel CACNA1c, cardiac troponin I, and connexin 43. The gel integrity was found to largely affect CDC cardiac differentiation. These results suggest that the developed dual-sensitive hydrogels may be promising carriers for cardiac cell therapy.

pH-Sensitive and Thermosensitive Hydrogels as Stem-Cell Carriers for Cardiac Therapy.

5xxx series aluminum alloys, as Al-4.5Mg-1.0Mn (AA5083), are strengthened by Mg solid solution and work hardening. A drawback of this alloy is the fact that β phase, Al3Mg2, can precipitate on grain boundaries causing sensitization and intergranular corrosion, which is detrimental to the integrity of the structure. Metallography is an important technique to study the grain structure and highly sought for intergranular corrosion evaluation; however, revealing the grains of completely un-sensitized AA5083 is challenging. This paper introduces a new procedure to etch AA5083 samples that were solutionized at 450°C for 1.5 h. The new procedure is a two-step etching method, including a phosphoric acid pre-etching step and a Weck's reagent coloring step. Solutionized, lightly sensitized, and as-received AA5083 were evaluated, and the grains were observed using optical microscopy. The microetching mechanism was further studied by optical profilometry, atomic force microscopy, scanning electron microscopy, and energy dispersive spectrometry. The phosphoric acid created a surface profile determined by the grain orientations and its reactivity, and the Weck's reagent was then able to color grains by preferential MnO2 formation over some pre-etched grains. Moreover, the final polishing with colloidal silica was essential to reach a high contrast image.

Mechanism of Etching of Al-4.5Mg-1.0Mn Alloy.

Multiple negative regulators restrict the ability of T cells to attack tumors. This work demonstrates the role of PI3K-interacting protein 1 (Pik3ip1) in restraining T-cell responses and antitumor immunity.

Pik3ip1 Is a Negative Immune Regulator that Inhibits Antitumor T-Cell Immunity.

Glioma is one of the most aggressive and common malignant brain tumors. Due to the presence of the blood-brain barrier (BBB), the effectiveness of therapeutics is greatly affected. In this work, to develop an efficient anti-glioma drug with targeting and which was able to cross the BBB, cell-penetrating peptides (R8) and transferrin co-modified doxorubicin (DOX)-loaded liposomes (Tf-LPs) were prepared. Tf-LPs possessed a spherical shape and uniform size with 128.64 nm and their ξ-potential was 6.81 mV. Tf-LPs were found to be stable in serum within 48 h. Uptake of Tf-LPs in both U87 and GL261 cells was analyzed by confocal laser scanning microscopy and by flow cytometry. Tf-LPs were efficiently taken up by both U87 and GL261 cells. Moreover, Tf-LPs exhibited sustained-release. The cumulative release of DOX from Tf-LPs reached ~50.0% and showed excellent anti-glioma efficacy. Histology of major organs, including brain, heart, liver, spleen, lungs and kidney, and the bodyweight of mice, all indicated low toxicity of Tf-LPs. In conclusion, Tf-LPs showed great promise as an anti-glioma therapeutic agent.

Cell-Penetrating Peptide and Transferrin Co-Modified Liposomes for Targeted Therapy of Glioma.

There are limited data on the association of membranous septum (MS) morphology and transcatheter heart valve (THV) implantation depth, and the development of new conduction abnormalities (CA) after transcatheter aortic valve implantation (TAVI).

Membranous septum morphology and risk of conduction abnormalities after transcatheter aortic valve implantation.

Technical Considerations for Transcatheter Aortic Valve Replacement With the Navitor Transcatheter Heart Valve.

The authors sought to investigate whether a patient-specific implantation technique during transcatheter aortic valve replacement (TAVR) can result in a safe and reproducible neo-commissural alignment of self-expanding transcatheter heart valves (THVs).

Patient-Specific Implantation Technique to Obtain Neo-Commissural Alignment With Self-Expanding Transcatheter Aortic Valves.

The aim of this study was to assess cusp symmetry and coronary ostial eccentricity and its impact on coronary access following transcatheter aortic valve replacement (TAVR) using a patient-specific commissural alignment implantation technique.

Cusp Symmetry and Coronary Ostial Eccentricity and its Impact on Coronary Access Following TAVR.

Calcium-Induced Infolding of a Self-Expanding Transcatheter Aortic Valve in Type 1 Bicuspid Aortic Valve Stenosis.

When reviewing our publications, an error in article [...].

Article	Year
Antitumor activity of a novel survivin siRNA. Pakistan journal of pharmaceutical sciences\| PubMed ID: 26525031	2015
pH-Sensitive and Thermosensitive Hydrogels as Stem-Cell Carriers for Cardiac Therapy. ACS applied materials & interfaces\| PubMed ID: 27064934	2016
Mechanism of Etching of Al-4.5Mg-1.0Mn Alloy. Microscopy and microanalysis : the official journal of Microscopy Society of America, Microbeam Analysis Society, Microscopical Society of Canada\| PubMed ID: 30047348	2018
Pik3ip1 Is a Negative Immune Regulator that Inhibits Antitumor T-Cell Immunity. Clinical cancer research : an official journal of the American Association for Cancer Research\| PubMed ID: 31350312	2019
Cell-Penetrating Peptide and Transferrin Co-Modified Liposomes for Targeted Therapy of Glioma. Molecules (Basel, Switzerland)\| PubMed ID: 31574945	2019
Membranous septum morphology and risk of conduction abnormalities after transcatheter aortic valve implantation. EuroIntervention : journal of EuroPCR in collaboration with the Working Group on Interventional Cardiology of the European Society of Cardiology\| PubMed ID: 34338638	2022
Technical Considerations for Transcatheter Aortic Valve Replacement With the Navitor Transcatheter Heart Valve. JACC. Cardiovascular interventions\| PubMed ID: 34538600	2021
Patient-Specific Implantation Technique to Obtain Neo-Commissural Alignment With Self-Expanding Transcatheter Aortic Valves. JACC. Cardiovascular interventions\| PubMed ID: 34538602	2021
Cusp Symmetry and Coronary Ostial Eccentricity and its Impact on Coronary Access Following TAVR. JACC. Cardiovascular interventions\| PubMed ID: 35057982	2022
Calcium-Induced Infolding of a Self-Expanding Transcatheter Aortic Valve in Type 1 Bicuspid Aortic Valve Stenosis. JACC. Cardiovascular interventions\| PubMed ID: 35093275	2022
Correction: Wang et al. Cell-Penetrating Peptide and Transferrin Co-Modified Liposomes for Targeted Therapy of Glioma. 2019, , 3540. Molecules (Basel, Switzerland)\| PubMed ID: 36080509	2022

Xi Wang

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