Synthetic mRNA – emerging new class of drug for tissue regeneration

Nanofibers produced by electrospinning represent a new class of promising scaffolds to support nerve regeneration. Here, we found that the blended solutions of chitosan (CS) with Poly (vinyl alcohol) (PVA) are appropriate for electrospinning when they form conductive, unstructured fluids displaying plasticity, rather than elasticity, in the bulk and at the interface. We then studied that utilize electrospun nanofibers to manipulate biological processes relevant to nervous tissue regeneration, including stem cell differentiation, guidance of neurite extension, and peripheral nerve injury treatments. The main objective of this article is to provide valuable methods for investigating the mechanisms of neurite growth on novel nanofibrous scaffolds and optimization of the nanofiber scaffolds and conduits for repairing peripheral nerve injuries.

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Enhancement of synthetic mRNA translation efficiency through engineered poly(A) tails

10.1101/2021.08.30.458298 ◽

2021 ◽

Author(s):

Yusheng Liu ◽

Hu Nie ◽

Rongrong Sun ◽

Jiaqiang Wang ◽

Falong Lu

Keyword(s):

Mrna Translation ◽

Human Cells ◽

Translation Efficiency ◽

New Class ◽

Novel Approach ◽

Synthetic Mrna

SUMMARYIn vitro transcribed (IVT) mRNA represents a new class of drug in both therapeutics and vaccines. Improving the translation efficiency of IVT mRNA remains a core challenge for mRNA-based applications. Here, using IVT mRNAs with poly(A) tails containing non-A residues which were recently revealed to be widespread in RNA poly(A) tails1,2, we unexpectedly find that non-A residues can effectively promote the mRNA translation. To further support our finding, we provide evidence that non-A residues associated with enhanced mRNA translation efficiency transcriptome-wide in mouse and human cells. Together, our study provides a novel approach to enhance mRNA translation efficiency by inclusion of non-A residues in the mRNA poly(A) tails, holding great potential to promote mRNA-based therapeutics and vaccines.

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Synthetic mRNA expressed Cas13a mitigates RNA virus infections

10.1101/370460 ◽

2018 ◽

Cited By ~ 4

Author(s):

Swapnil S. Bawage ◽

Pooja M. Tiwari ◽

Philip J. Santangelo

Keyword(s):

Influenza Virus ◽

Respiratory Syncytial Virus ◽

Nucleic Acids ◽

Rna Virus ◽

Virus Infections ◽

Viral Pathogens ◽

New Class ◽

Syncytial Virus ◽

Synthetic Mrna ◽

Over Time

AbstractThe emergence of the CRISPR-Cas system as a technology has transformed our ability to modify nucleic acids. Prokaryotes evolved one member of this family, CRISPR-Cas effector, Cas13a, as an RNA-guided ribonuclease that protects them from invading bacteriophages. Here, we demonstrate that Cas13a can be programmed to target eukaryotic viral pathogens, influenza virus A (IVA) and human respiratory syncytial virus (hRSV) in human cells. We designed synthetic mRNA coding for Cas13a, which when guided by CRISPR RNAs (crRNA) to target influenza virus or hRSV RNA, significantly mitigates these infections both prophylactically, therapeutically, and over time. These data demonstrate a possible new class of synthetic mRNA-powered anti-viral interventions.One Sentence SummarycrRNA guided Cas13a halts RNA virus infections

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In Situ microscopy of the anodic etching of silicon

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100137537 ◽

1995 ◽

Vol 53 ◽

pp. 232-233

Author(s):

Frances M. Ross ◽

Peter C. Searson

Keyword(s):

Composite Structures ◽

High Surface ◽

High Surface Area ◽

Chemical Properties ◽

Selective Etching ◽

Silicon On Insulator ◽

Second Phase ◽

Porous Layers ◽

New Class ◽

Porous Semiconductors

Porous semiconductors represent a relatively new class of materials formed by the selective etching of a single or polycrystalline substrate. Although porous silicon has received considerable attention due to its novel optical properties1, porous layers can be formed in other semiconductors such as GaAs and GaP. These materials are characterised by very high surface area and by electrical, optical and chemical properties that may differ considerably from bulk. The properties depend on the pore morphology, which can be controlled by adjusting the processing conditions and the dopant concentration. A number of novel structures can be fabricated using selective etching. For example, self-supporting membranes can be made by growing pores through a wafer, films with modulated pore structure can be fabricated by varying the applied potential during growth, composite structures can be prepared by depositing a second phase into the pores and silicon-on-insulator structures can be formed by oxidising a buried porous layer. In all these applications the ability to grow nanostructures controllably is critical.

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The microtubule associated protein (MAP) tau forms a new class of triple-stranded left-hand helical fibrous protein polymer

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100123106 ◽

1992 ◽

Vol 50 (1) ◽

pp. 540-541

Author(s):

G. C. Ruben ◽

K. Iqbal ◽

I. Grundke-Iqbal ◽

H. Wisniewski ◽

T. L. Ciardelli ◽

...

Keyword(s):

Axial Ratio ◽

Normal Structure ◽

Paired Helical Filaments ◽

Left Hand ◽

New Class ◽

Protein Polymer ◽

Fibrous Protein ◽

Protein Map ◽

Neurotransmitter Transport ◽

Alzheimer Neurofibrillary Tangles

In neurons, the microtubule associated protein, tau, is found in the axons. Tau stabilizes the microtubules required for neurotransmitter transport to the axonal terminal. Since tau has been found in both Alzheimer neurofibrillary tangles (NFT) and in paired helical filaments (PHF), the study of tau's normal structure had to preceed TEM studies of NFT and PHF. The structure of tau was first studied by ultracentrifugation. This work suggested that it was a rod shaped molecule with an axial ratio of 20:1. More recently, paraciystals of phosphorylated and nonphosphoiylated tau have been reported. Phosphorylated tau was 90-95 nm in length and 3-6 nm in diameter where as nonphosphorylated tau was 69-75 nm in length. A shorter length of 30 nm was reported for undamaged tau indicating that it is an extremely flexible molecule. Tau was also studied in relation to microtubules, and its length was found to be 56.1±14.1 nm.

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Study of segregation in La1.8Sr0.2CuO4 superconductor by STEM-EDS microanalysis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100125294 ◽

1987 ◽

Vol 45 ◽

pp. 54-55

Author(s):

T. F. Kelly ◽

P. J. Lee ◽

E. E. Hellstrom ◽

D. C. Larbalestier

Keyword(s):

Rare Earth ◽

High Field ◽

Transport Current ◽

Total Thickness ◽

New Class ◽

Ceramic Superconductors ◽

Current Densities ◽

Group Ii ◽

Eds Microanalysis

Recently there has been much excitement over a new class of high Tc (>30 K) ceramic superconductors of the form A1-xBxCuO4-x, where A is a rare earth and B is from Group II. Unfortunately these materials have only been able to support small transport current densities 1-10 A/cm2. It is very desirable to increase these values by 2 to 3 orders of magnitude for useful high field applications. The reason for these small transport currents is as yet unknown. Evidence has, however, been presented for superconducting clusters on a 50-100 nm scale and on a 1-3 μm scale. We therefore planned a detailed TEM and STEM microanalysis study in order to see whether any evidence for the clusters could be seen.A La1.8Sr0.2Cu04 pellet was cut into 1 mm thick slices from which 3 mm discs were cut. The discs were subsequently mechanically ground to 100 μm total thickness and dimpled to 20 μm thickness at the center.

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Electronic structure studies of conducting polymers by electron energy-loss spectroscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100163265 ◽

1996 ◽

Vol 54 ◽

pp. 160-161

Author(s):

J. Fink

Keyword(s):

Electronic Structure ◽

Conducting Polymers ◽

Conjugated Polymers ◽

Electron Acceptors ◽

Electron Donors ◽

Light Emitting ◽

One Dimensional ◽

New Class ◽

Electrical Conductivities ◽

Electron Energy Loss

Conducting polymers comprises a new class of materials achieving electrical conductivities which rival those of the best metals. The parent compounds (conjugated polymers) are quasi-one-dimensional semiconductors. These polymers can be doped by electron acceptors or electron donors. The prototype of these materials is polyacetylene (PA). There are various other conjugated polymers such as polyparaphenylene, polyphenylenevinylene, polypoyrrole or polythiophene. The doped systems, i.e. the conducting polymers, have intersting potential technological applications such as replacement of conventional metals in electronic shielding and antistatic equipment, rechargable batteries, and flexible light emitting diodes.Although these systems have been investigated almost 20 years, the electronic structure of the doped metallic systems is not clear and even the reason for the gap in undoped semiconducting systems is under discussion.

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Mechanochemical changes on cyclometalated Ir(iii) acyclic carbene complexes – design and tuning of luminescent mechanochromic transition metal complexes

Inorganic Chemistry Frontiers ◽

10.1039/c9qi01278h ◽

2020 ◽

Vol 7 (3) ◽

pp. 786-794 ◽

Cited By ~ 3

Author(s):

Jingqi Han ◽

Kin-Man Tang ◽

Shun-Cheung Cheng ◽

Chi-On Ng ◽

Yuen-Kiu Chun ◽

...

Keyword(s):

Transition Metal ◽

Metal Complexes ◽

Transition Metal Complexes ◽

Carbene Complexes ◽

New Class

A new class of luminescent cyclometalated Ir(iii) complexes with readily tunable mechanochromic properties derived from the mechanically induced trans-to-cis isomerization have been developed.

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Amino-functional polyethers: versatile, stimuli-responsive polymers

Polymer Chemistry ◽

10.1039/d0py00466a ◽

2020 ◽

Vol 11 (24) ◽

pp. 3940-3950 ◽

Cited By ~ 2

Author(s):

Patrick Verkoyen ◽

Holger Frey

Keyword(s):

Ring Opening ◽

Review Article ◽

Stimuli Responsive ◽

New Class ◽

Stimuli Responsive Polymers ◽

Responsive Polymers

Amino-functional polyethers have emerged as a new class of “smart”, i.e. pH- and thermoresponsive materials. This review article summarizes the synthesis and applications of these materials, obtained from ring-opening of suitable epoxide monomers.

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Decellularized bone extracellular matrix in skeletal tissue engineering

Biochemical Society Transactions ◽

10.1042/bst20190079 ◽

2020 ◽

Vol 48 (3) ◽

pp. 755-764

Author(s):

Benjamin B. Rothrauff ◽

Rocky S. Tuan

Keyword(s):

Tissue Engineering ◽

Bone Regeneration ◽

Tissue Regeneration ◽

Animal Studies ◽

Tumor Resection ◽

Regenerative Capacity ◽

Skeletal Tissue ◽

Large Bone

Bone possesses an intrinsic regenerative capacity, which can be compromised by aging, disease, trauma, and iatrogenesis (e.g. tumor resection, pharmacological). At present, autografts and allografts are the principal biological treatments available to replace large bone segments, but both entail several limitations that reduce wider use and consistent success. The use of decellularized extracellular matrices (ECM), often derived from xenogeneic sources, has been shown to favorably influence the immune response to injury and promote site-appropriate tissue regeneration. Decellularized bone ECM (dbECM), utilized in several forms — whole organ, particles, hydrogels — has shown promise in both in vitro and in vivo animal studies to promote osteogenic differentiation of stem/progenitor cells and enhance bone regeneration. However, dbECM has yet to be investigated in clinical studies, which are needed to determine the relative efficacy of this emerging biomaterial as compared with established treatments. This mini-review highlights the recent exploration of dbECM as a biomaterial for skeletal tissue engineering and considers modifications on its future use to more consistently promote bone regeneration.

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