Manufacturability and Properties of Granules and Tablets Using the Eco-Friendly Granulation Method Green Fluidized Bed Granulation Compared to Direct Compression.

This study aimed to compare the manufacturability and granule and tablet properties of green fluidized bed granulation (GFBG) and of direct compression (DC). Acetaminophen was used as a low compactability model drug. The process time of GFBG to produce final mixtures was comparable to that of DC, and thus GFBG could be considered a simple process.

Importance of free water in controlling granule and tablet properties in a novel granulation method, green fluidized bed granulation (GFBG).

In the pharmaceutical field, green fluidized bed granulation (GFBG) is a novel and eco-friendly manufacturing technology used to produce desired granules via simple blending and spraying steps at ambient temperature using a standard fluidized bed granulator. However, the relations between water content and granule and tablet qualities have not yet been elucidated for GFBG. The purpose of this study was to elucidate the influence of different water quantities used in the GFBG process on granule and tablet qualities.

Novel, lean and environment-friendly granulation method: Green fluidized bed granulation (GFBG).

The Green fluidized bed granulation (GFBG) technology is based on the moisture activated dry granulation (MADG) technique and consists only of a mixing and a spraying process using a fluidized bed granulator, requiring no heating process. This provides a less energy-consuming and environment-friendly granulation method compared to current fluidized bed granulation (FBG) and high-shear granulation (HSG) methods. The aim of this study is to compare and evaluate the manufacturability, and granule and tablet properties among GFBG, MADG, FBG and HSG.

Thermodynamic and kinetic effects of morpholino modification on pyrimidine motif triplex nucleic acid formation under physiological condition.

Due to instability of pyrimidine motif triplex nucleic acid under physiological pH and low magnesium ion concentration, stabilization of the triplex under the physiological condition is crucial in improving its therapeutic potential to artificially control gene expression in vivo. To this end, we investigated the thermodynamic and kinetic effects of morpholino (MOR) modification of triplex-forming oligonucleotide (TFO) on the triplex formation under the physiological condition. The thermodynamic analyses indicated that the MOR modification of TFO not only significantly increased the thermal stability of the triplex but also increased the binding constant for the triplex formation by nearly 2 orders of magnitude.

Synergistic stabilization of nucleic acid assembly by 2'-O,4'-C-methylene-bridged nucleic acid modification and additions of comb-type cationic copolymers.

Stabilization of nucleic acid assemblies, such as duplex and triplex, is quite important for their wide variety of potential applications. Various stabilization methods, including molecular designs of chemically modified nucleotides and hybrid stabilizers, and combinations of different stabilization methods have been developed to increase stability of nucleic acid assemblies. However, combinations of two stabilizing methods have not always yielded desired synergistic effects.

The interaction between the purine motif triplex and the triplex DNA-binding domain of Saccharomyces cerevisiae Stm1 protein.

Saccharomyces cerevisiae Stm1 protein (273 amino acids) is a purine motif triplex DNA-binding protein. We have previously found that Stm(1-113) (amino acids 1-113) is the minimal domain to specifically bind with the purine motif triplex. Here, to reveal the triplex recognition mechanism of Stm(1-113), we have examined the interaction between Stm(1-113) and each of the purine motif triplexes with various lengths and base sequences.

Triplex formation-based artificial transcription factor to regulate target gene expression.

A triplex formation-based artificial transcription factor to recognize any upstream sequence of target genes was developed to regulate the target gene expression. The artificial transcription factor contains a single-stranded RNA to bind with duplex DNA of the upstream sequence of the target gene to form triplex, and an effecter domain, such as activation or repression domain, of transcription factor. Reporter beta-galactosidase activity in yeast was increased 1.

Location of the triplex DNA-binding domain of Saccharomyces cerevisiae Stm1 protein.

Saccharomyces cerevisiae Stm1 protein (273 amino acids) is a purine motif triplex DNA-binding protein. Here, to examine the location of the triplex DNA-binding domain of Stm1 protein, we analyzed the interaction between the purine motif triplex and a series of truncated Stm1 proteins by electrophoretic mobility shift assay. Stm(1-113) (amino acids 1-113) was able to bind with the purine motif triplex.

Computational evaluation of the specific interaction between cation and mismatch base pair.

Ab initio calculations were carried out to characterize the structure and energetic of silver cation (Ag (I)) complex with cytosine (C:Ag:C) and mercury cation (Hg (II)) complex with thymine (T:Hg:T) systems. These metal-modified mismatch base pairs have been optimized using Hatree-Fock method without any symmetry constrains. Using above methods, the models of Ag (I) in a crosslink between O2 carbonyl oxygen of cytosine, O2(C):Ag:O2(C), and Hg (II) in a crosslink between N3 nitrogen atom of thymine, N3(T):Hg:N3(T) were obtained.

Synergistic stabilization of triplex by combination of comb-type cationic copolymer and 2',4'-BNA.

We examined the effect of the combination of the two triplex-stabilizing factors, poly(L-lysine)-graft-dextran (PLL-g-Dex) copolymer and 2'-O,4'-C-methylene bridged nucleic acid (2',4'-BNA) backbone modification of triplex-forming oligonucleotide (TFO), on the pyrimidine motif triplex formation at neutral pH, a condition where pyrimidine motif triplexes are unstable. The combination of both stabilizing factors that was the triplex involving the 2',4'-BNA TFO in the presence of the copolymer synergistically increased the thermal stability of the pyrimidine motif triplex at neutral pH. The present results certainly support the idea that the combination of the stabilizing factors can be a key method for triplex stabilization and may lead to progress in therapeutic applications of the antigene strategy in vivo.

Thermodynamic analyses of purine motif triplex DNA formation.

We analyzed the thermodynamics of purine motif triplex formations involving single mismatches of four different base triplets (A x A:T, T x A:T, A x T:A and T x T:A) by isothermal titration calorimetry. The T x A:T and A x A:T base triplets are the most stable and the A x T:A base triplet is the least stable among the four base triplets. The magnitude of the Gibbs free energy change varies within 1.