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Adoption of DNA as a data storage medium could be accelerated with specialized synthesis processes and codecs. The authors describe TdT-mediated DNA synthesis in which data is stored in transitions between non-identical nucleotides and the use of synchronization markers to provide error tolerance.

Bioorthogonal reactions are known as types of chemical reactions without the interference from biological reactions within the living systems. The requirements for such reactions include activities in aqueous environment, mild temperature, and physiological pH. One of the facile ways, for detecting bioorthogonal reactions, is covalently attaching a florescent compound to biomolecules such as proteins. In this work, two novel derivatives of fluorescein, 5(6)acylchloride fluorescein and 5(6)thiophenol fluorescein, were synthesized. The products were confirmed using 1H NMR. Subsequently, the reactions of the synthesized derivatives of with Bovine Serum Albumin (BSA) and Hen Egg white lysozyme (HEWL), under physiological conditions, were investigated. The advantages of reactions of the derivatives with proteins can include selectivity towards lysine, high kinetics of reactions, and low concentrations of reactants.The fluorescein-attached proteins were purified using size-exclusion chromatography and dialysis. The success of covalent attachments to proteins was confirmed using SDS-poly acrylamide gel electrophoresis. The reactivity of 5(6)thiophenol fluorescein towards BSA was investigated at pH 7 and pH 9.

Objective: MiR-302-367 is a cluster of polycistronic microRNAs that are exclusively expressed in embryonic stem (ES) cells. The miR-302-367 promoter is functional during embryonic development but is turned off in later stages. Motivated by the cancer stem cell hypothesis, we explored the potential expression of miR-302 in brain tumor cell lines. Materials and Methods: In the present experimental study, we have tried to expand our knowledge on the expression pattern and functionality of miR302 cluster by quantifying its expression in a series of glioma (A-172, 1321N1, U87MG) and medulloblastoma (DAOY) cell lines. To further assess the functionality of miR-302 in these cell lines, we cloned its promoter core region upstream of the enhanced green fluorescent protein (EGFP) or luciferase encoding genes. Results: Our data demonstrated a very low expression of miR-302 in glioma cell lines, compared with that of embryonal carcinoma cell line NT2 being used as a positive control. The expression of miR-302 promoter-EGFP construct in the aforementioned cell lines demonstrated GFP expression in a rare subpopulation of the cells. Serum deprivation led to the generation of tumorospheres, enrichment of miR-302 positive cells and upregulation of a number of pluripotency genes. Conclusion: Taken together, our data suggest that miR-302 could potentially be used as a novel putative cancer stem cell marker to identify and target cancer stem cells within tumor tissues.

In searching for alternative ways to reduce or inhibit amyloid formation, we have studied this process using hen egg white lysozyme (HEWL) in the presence of a low concentration of protic ionic liquids. The ionic liquids were synthesized in a combinatorial fashion maintaining the cationic part (tetramethylguanidinium) with alteration of the anionic component of each compound tested. It was observed that one of these compounds (tetramethylguanidinium acetate) inhibited amyloid formation of HEWL in vitro by nearly 50%. Examination under transmission electron microscopy confirmed the fibril inhibition, and fibrils were observed to be morphologically thinner. To investigate the mechanism of inhibition, intrinsic fluorescence, ANS binding, and circular dichroism analyses were performed. These analyses indicated that the native structure of HEWL was maintained in the presence of the ionic liquid. Performing native PAGE and nondenaturing agarose electrophoresis, it became evident that some of the intermediate oligomers were not converted to protofibrils and that the oligomers were trapped in more stable conformations. Additionally, it was observed that this inhibitory effect was related to the ionic liquid itself and not the solvated ions. It also became evident that the carboxyl functional group was important in the inhibition. The size of the anions and kosmotropicity did not play significant roles in the fibril inhibition. [ABSTRACT FROM AUTHOR]

SO3H-functionalized ionic liquid was successfully applied as a water tolerant-acidic catalyst for the one-pot domino approach quinoline synthesis in aqueous medium. Various types of quinolines from 2-aminoaryl ketones and β-ketoesters/ketones were prepared in 85−98% yields using the catalytic system of SO3H-functionalized ionic liquid/H2O. The ionic liquids was synthesized in a combinatorial fashion. The quinoline products could be conveniently separated from the reaction mixture by filtration, indicating that the whole process was performed in water and exemplifying a green chemistry. More importantly, the catalyst could be easily recycled for five times without loss of much activity. The catalytic system, reported here, possesses advantages of both homogeneous and heterogeneous catalysts. [ABSTRACT FROM AUTHOR]

Keratinocyte Growth Factor (KGF) is a paracrine-acting and epithelium-specific growth factor produced by cells of mesenchymal origin. Based on preclinical data, recombinant KGF plays a critical role in protecting and repairing of damaged epithelial tissues. Despite great efforts to express recombinant human KGF(rhKGF) in different organisms, attempts for finding appropriate protein expression system with the ability of producing a properly folded and processed KGF needs further investigation. Pichia pastoris has been used successfully and extensively for production of industrial enzymes and pharmaceutical proteins. Herein, we investigated the affect of pro-region-α-factor early deletion on production and secretion of rhKGF in Pichia pastoris. Initially, expression of human KGF induced in MCF-7 cell line treated with 1, 25-Dihydroxy vitamin D3. The coding sequence of full-length rhKGF194 was then cloned into the yeast integrative expression vector, downstream of α-factor and was integrated into P. pastoris genome. KGF protein was expressed in P. pastoris x33 cells, usingα-factor signal peptide for translocation of KGF to ER. An internal human signal peptide was also arranged after α-factorfor early removal of the pro-region in ER. RT-PCR results demonstrated that KGF mRNA was expressed successfully after induction by methanol. Recombinant KGF protein expression was detected by Western blotting in cell lysats, but not in conditioned media. A molecular weight of 17 kD for rhKGF194 indicates that the α-factor and internal human signal peptideshad been removed in x33 cells. The results indicate that in the absence of pro-region-α-factor, the recombinant KGF protein was not efficiently processed and transported within the biosynthesis-secretory pathway. As KGF protein is an unstable growth factor and tend to aggregate because of some native properties, It seems that presence of a chaperon molecule fusion with KGF is necessary for efficient secretion of the recombinant protein.

PURPOSE: To investigate and compare the expression of OCT4B1 between tumor and non-tumor bladder tissues. MATERIALS AND METHODS: We investigated the expression of OCT4B1 in 30 tumor and non-tumor surgical specimens of the bladder, using the TaqMan real-time polymerase chain reaction approach and by carefully designing primers and probes specific for the amplification of the variant. RESULTS: Most tumor and non-tumor samples of the bladder showed OCT4B1 expression, but its expression level was significantly higher in the tumors (P < .002). Moreover, the up-regulation of OCT4B1 was more significant in high-grade tumors compared to the low-grade ones (P < .05). We have also employed the RNA interference strategy to evaluate the functional role of OCT4B1 in a bladder cancer cell line, 5637. Suppression of OCT4B1 caused some changes in cell cycle distribution, and significantly elevated the rate of apoptosis in the cells. CONCLUSION: Our findings suggest that OCT4B1 plays a potential role in tumor initiation and/or progression of the bladder cancer. Additionally, OCT4B1 can be regarded as a new tumor marker for detection, classification, and treatment of the bladder cancer. However, more experimental studies are needed to replicate our findings.

Purpose: To investigate and compare the expression of OCT4B1 between tumor and non-tumor bladder tissues. Materials and Methods: We investigated the expression of OCT4B1 in 30 tumor and non-tumor surgical specimens of the bladder, using the TaqMan real-time polymerase chain reaction approach and by carefully designing primers and probes specific for the amplification of the variant. Results: Most tumor and non-tumor samples of the bladder showed OCT4B1 expression, but its expression level was significantly higher in the tumors (P < .002). Moreover, the up-regulation of OCT4B1 was more significantly in high-grade tumors compared to the low-grade ones (P < .005). We have also employed the RNA interference strategy to evaluate the functional role of OCT4B1 in a bladder cancer cell line, 5637. Suppression of OCT4B1 caused some changes in cell cycle distribution, and significantly elevated the rate of apoptosis in the cells. Conclusion: Our findings suggest that OCT4B1 plays a potential role in tumor initiation and/or progression of the bladder cancer. Additionally, OCT4B1 can be regarded as a new tumor marker for detection, classification, and treatment of the bladder cancer. However, more experimental studies are needed to replicate our findings. [ABSTRACT FROM AUTHOR]

SO(3)H-functionalized ionic liquid was successfully applied as a water tolerant-acidic catalyst for the one-pot domino approach quinoline synthesis in aqueous medium. Various types of quinolines from 2-aminoaryl ketones and beta-ketoesters/ketones were prepared in 85-98% yields using the catalytic system of SO(3)H-functionalized ionic liquid/H(2)O. The ionic liquids was synthesized in a combinatorial fashion. The quinoline products could be conveniently separated from the reaction mixture by filtration, indicating that the whole process was performed in water and exemplifying a green chemistry. More importantly, the catalyst could be easily recycled for five times without loss of much activity. The catalytic system, reported here, possesses advantages of both homogeneous and heterogeneous catalysts.