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Sialylation, which is considered as a critical quality attribute, plays important roles in pharmacokinetics of recombinant proteins. Terminal sialic acids of glycoproteins are modulated by intracellular sialyltransferase (ST) and extracellular sialidase. Since CHO cells producing recombinant proteins can only transfer α2,3-sialic acid to a nascent oligosaccharide, inactivation of α2,6-ST results in a different composition of glycan with human proteins, which have predominantly α2,6-linkages. To overcome this problem and maximize total sialic acid contents, we used glucocorticoids (GCs) that are classified as a steroid hormone in CHO cells expressing both α2,3-ST and α2,6-ST. This study was performed to determine the effect of GCs on CHO cell cultures and sialylation of Fc-fusion protein. We observed that all cultures supplemented with GCs reduced the titer of the Fc-fusion protein, but enhanced the sialylation level, when compared to those of control. Especially, addition of corticosterone increases the levels of α2,6-sialylation as well as the total contents of sialic acid. Enhanced sialic acid contents are thought to be due to the intracellular improvement by sialylatransferase and the inhibition of sialidase. In conclusion, GCs can be utilized as an effective medium additive to improve the quality of biopharmaceuticals using CHO cell cultures.

The optimal transfection conditions for efficient transgene delivery into a specific cell type should be empirically determined, particularly in cases involving unusual cell types. We compared the conditions for effective introduction of transgenes into Siberian sturgeon (Acipenser baerii) cell lines by evaluating the cytotoxicity and transfection efficiency of three commercially available transfection reagents: Lipofectamine 2000, X-tremeGENE HP DNA Transfection Reagent, and GeneJuice Transfection Reagent. Plasmid vectors containing the gene encoding enhanced green fluorescent protein were mixed with each of the transfection reagents using reagent-to-plasmid ratios of 1:1, 2:1, and 4:1. Then, the complexes were used to transfect three Siberian sturgeon cell lines derived from the heart, head kidney, and gonad. Cytotoxicity and transfection efficiency were measured via flow cytometry after propidium iodide staining. No significant cytotoxicity was observed at the optimal treatment conditions in all cases, with the exception of Lipofectamine 2000-treated gonad-derived cells. Although the transfection efficiencies in A. baerii cells were generally low, X-tremeGENE HP DNA Transfection Reagent showed the highest transfection efficiency at ratios of 2:1 or 4:1, depending on the cell type. Hence, X-tremeGENE HP DNA Transfection Reagent can be used to effectively transfer foreign genes into three A. baerii cell lines.

The platinum compartment complex [Pt(L)] (1) was synthesized by refluxing a mixture of [PtCl2(SMe2)2], the free ligand (H2L = N,N′-bis(3-methoxysalicylidenimino-1,3-diaminopropane)), and triethylamine in methanol. Complex 1, the first platinum complex of the N2O2–O2O′2-type bi-compartmental ligand, was treated with lanthanide nitrates to give bimetallic Pt–Ln compartment complexes [PtLn(L)(NO3)3] (Ln = Eu (2), Tb (3)). The corresponding palladium analogues, [PdLn(L)(NO3)3] (Ln = Eu (4), Tb (5)), could be prepared from the palladium compartment complex [Pd(L)] and lanthanide nitrates. Structures of all complexes were determined by single X-ray crystallography. Emission quenching of the Ln3+ ions was observed for complexes 2–5 and ascribed to the radiation-less energy loss from excited Ln3+ to M2+ (Ln = Eu, Tb; M = Pd, Pt).

An air-stable N-heterocyclic carbene-copper thiophene-2-carboxylate (CuTC) complex has been prepared for the stereoselective hydroboration of terminal alkynes using pinacolborane (HBpin) or 1,8-naphthalenediaminatoborane (HBdan). The newly synthesized complex can be directly activated by hydroboranes without a cocatalyst such as a base, and exhibits high reactivity for the hydroboration of alkynes under mild conditions. A gram-scale hydroboration of terminal phenylacetylene demonstrated the applicability of the copper complex for the preparation of alkenyl boronates.

A series of novel Nb(V) tBu-imido/N-alkoxy carboxamide complexes, NbCl2(NtBu)(pyridine)(edpa) (1), NbCl2(NtBu)(pyridine)(mdpa) (2), and Nb(NtBu)(mdpa)3 (3), were successfully synthesized by metathesis reaction between Nb(NtBu)Cl3(py)2 and several equivalents of Na(edpa) (edpaH = Nethoxy-2,2-dimethylpropanamide) and Na(mdpa) (mdpaH = N-methoxy-2,2-dimethylpropanamide). These complexes could potentially serve as precursors for Nb-containing thin films. Compounds 1–3 were characterized by FT-IR and 1H and 13C NMR spectroscopies, elemental analysis, and thermogravimetric analysis (TGA). Single crystal X-ray diffraction analysis suggested that complex 3 has a distorted pentagonal bipyramidal geometry around the central Nb atom, with three bidentate mdpa ligands and one tBu imido group saturating the coordination. TGA analysis revealed that the thermal characteristics of 3 were superior to those of 1 and 2. All prepared complexes were able to be distilled or sublimed and expected potential precursors for the fabrication of thin films.

This paper reports the synthesis, crystal structures, and thermal behavior of two zinc–gadolinium (3d–4f) coordination polymers by adjusting the connectivity of a secondary building unit (SBU) with two pyridyl–carboxylic acids as linkers. As a SBU, the Zn–Gd compartment compound, [ZnGd(L)(NO3 )(CH3CN)(H2O)4](NO3 )2(H2O) (H2L = 1,3-bis((3-methoxysalicylidene)amino)propane), was used. Under microwave heating conditions, the SBU reacted with 4-pyridinepropionic acid (4-Hppa) and 4-pyridinecarboxylate (4-Hpca) to create a 1D polymer, [ZnGd(L)(NO3 )2(4-ppa)(EtOH)], and a 2D polymer, [ZnGd(L)(NO3 )2(4-pca)], respectively. Dimensionality of the products appeared to depend on the continuity of π conjugation of the external linking ligand.

This paper describes the preparation of four 3d–4f (3d = Zn; 4f = Eu, Tb) coordination polymers and their emission quenching of the lanthanide ions. Two dinuclear Zn–Ln compartment compounds, [ZnLn(L)(NO3)(CH3CN)(H2O)4](NO3)2(H2O) (Ln = Eu, Tb), were prepared at room temperature by stirring an acetonitrile solution containing [Zn(L)] (H2 L = 1,3-bis((3-methoxysalicylidene)amino)propane) and Ln(NO3)3·n(H2O). When these compounds were treated with 4-pyridinepropionic acid (4-Hppa) under microwave-heating conditions, one-dimensional Zn–Ln coordination polymers were formed: [ZnLn(L)(NO3)2(4-ppa)(EtOH)] (Ln = Eu (1), Tb (2)). By contrast, these compounds reacted with pyridine-4-carboxylic acid (4-Hpca) to give two-dimensional Zn–Ln coordination polymers: [ZnLn(L)(NO3)2(4-pca)(H2O)] (Ln = Eu (3), Tb (4)). All the compounds (1–4) exhibited the emission quenching of the Ln3+ ion, probably due to the Ln3+ → Zn2+ energy transfer.

The Pd(II) bis(benzonitrile) complex [Pd(PhCN)2Cl2] reacted with a mixture of 2-hydroxy-3-methoxybenzaldehyde, 1,3-diaminopropane, and triethylamine in acetonitrile to produce [Pd(L1)Cl] (HL1 = (E)-2-(((3-aminopropyl)imino)methyl)-6-methoxyphenol) (1), which contains an imine–amine-type macrocyclic ligand and a chloro ligand. Complex 1 was converted into a cyclohexane-like palladacycle, [Pd(NH2CH2CH2CH2NH2)Cl2] (2), when heated in acetonitrile at 80 °C for 60 h. The palladium compartment complex [Pd(L2)] (H2 L2 = N,N′-bis(3-methoxysalicylidenimino-1,3-diaminopropane) (3) was obtained from the free bis(imine) ligand (H2L2) and [Pd(PhCN)2Cl2] or Pd(OAc)2 in methanol. All complexes were structurally characterized by X-ray diffraction. Complex 3 is the first structurally characterized palladium compartment complex, in which the compartment ligand has an inner N2O2 and an outer O2O′2 compartments. The coordination geometry of the palladium metal in all complexes (1–3) can be best described as square-planar.

We introduce a transparent windshield-glass heater produced via transparent electrodes using silver nanowire (AgNW) networks for conventional use in the automobile industry. A high-quality conducting hybrid film is deposited on a plasma-treated glass substrate by spraying AgNWs, immersing the sprayed product in positively charged adhesive polymer solution, and then spraying negatively charged graphene oxide (GO) and a silane layer as an over-coating layer (OCL).The results of heating tests conducted after adhesion tests show that the sheet resistance changes with the application of polymer glue. Surprisingly, the transmittance of the film with the GO OCL is higher than that of the film without the GO OCL. Heating and defrosting tests are carefully conducted via infrared (IR) monitoring. Adhesive-polymer-treated and GO-protected AgNW transparent glass heaters exhibit the best performance with low sheet resistance; thus, through strong electrostatic interaction among the substrate, adhesive layer, and OCL, our AgNW hybrid glass heater can reach the target temperature with a standard vehicle voltage of 12 V in a short period of time.

In this paper, a cost-effective method for mass production of optically transparent super-hydrophobic PDMS thin film is proposed and characterized. The dual-scaled micro-/nano PDMS patterns are re-replicated using a photoresist mold (reverse image), PDMS mold (dual-scaled positive structures) and UV curable polyurethane acrylate (PUA, negative structures) mold. The PUA mold can be employed as a reusable mold for continuous production of the super-hydrophobic PDMS thin film in a home-made roll-to-roll system. The proposed method is extremely simple and cost-effective in comparing with previous methods. Thanks to the proposed PUV mold and the roll to roll system, continuous production of transparent super-hydrophobic PDMS film is possible, which will be a basis for mass production. The experimental results reveal that the proposed method has great potential to extend the utility of the optically transparent super-hydrophobic thin film.

In this study, the relationship between the steric hindrance of the alpha carbon substituent group of aminoalkoxy ligand and formation of germanium telluride (GeTe) and antimony telluride (Sb2Te3) was elucidated. A series of germanium and antimony precursors was prepared using aminoalkoxide-type bidentate ligands of different sizes such as dmampH, dmapH and dmaeH. These precursor materials were further treated with bis(trimethylsilyl)telluride in hexadecane through thermal reaction and studied with powder X-ray diffraction (pXRD) to compare the formation of germanium telluride (GeTe) and antimony telluride (Sb2Te3) alloys which are potential precursor materials for phase change random access memory devices. While the pXRD patterns of the thermal reaction materials of compounds 2 and 3 at 190 °C revealed a rhombohedral phase of GeTe and tellurium, compounds 5 and 6 at 190 °C showed a rhombohedral phase of Sb2Te3 and tellurium at this temperature. These results suggested that the formation of chalcogenide alloys was more favorable when relatively less bulk ligand was used.

Polyamide (PA) oligomers, which are the hard segment of poly(ether-block-amide) (PEBA), presenting thermoplastic and high performance elastomeric properties were prepared by polycondensation between 4-aminobenzoic acid and 12-aminododecanoic acid. Subsequently PEBAs were obtained by addition polymerization of the PA oligomers and various molecular weights of poly(tetramethylene glycol) (PTMG). The structure of the final PEBA was identified by using FTIR and NMR and the thermal properties depending on changes in the structure of hard segment were collected by using DSC and UTM analysis. As the results, the melt temperature (), the initial modulus, and the maximum strength of PEBAs increased with an increase in aromatic moiety up to 30% without reducing crystallinity.

Previous work has shown that certain steroidal bis-(N-pheny)ureas, derived from cholic acid, form crystals in the P6(1) space group with unusually wide unidimensional pores. A key feature of the nanoporous steroidal urea (NPSU) structure is that groups at either end of the steroid are directed into the channels and may in principle be altered without disturbing the crystal packing. Herein we report an expanded study of this system, which increases the structural variety of NPSUs and also examines their inclusion properties. Nineteen new NPSU crystal structures are described, to add to the six which were previously reported. The materials show wide variations in channel size, shape, and chemical nature. Minimum pore diameters vary from similar to 0 up to 13.1 angstrom, while some of the interior surfaces are markedly corrugated. Several variants possess functional groups positioned in the channels with potential to interact with guest molecules. Inclusion studies were performed using a relatively accessible tris-(N-phenyl)urea. Solvent removal was possible without crystal degradation, and gas adsorption could be demonstrated. Organic molecules ranging from simple aromatics (e.g., aniline and chlorobenzene) to the much larger squalene (M-w = 411) could be adsorbed from the liquid state, while several dyes were taken up from solutions in ether. Some dyes gave dichroic complexes, implying alignment of the chromophores in the NPSU channels. Notably, these complexes were formed by direct adsorption rather than cocrystallization, emphasizing the unusually robust nature of these organic molecular hosts.

Among 23 cytochrome P450s, CYP125A4 was proposed as a putative monooxygenase based on the high level of amino acid sequence homology (54% identity and 75% similarity) with the well characterized C27-steroid CYP125A1. Utilizing MTBCYP125A1 as a template, homology modeling of SPCYP125A4 was conducted by Accelrys Discovery Studio 3.1 software. The modeled SPCYP125A4 structure with lowest energy value was subsequently assessed for its stereochemical quality and side-chain environment. The final model was generated by showing its active site through the molecular dynamics. The docking of steroids showed broad specificity of SPCYP125A4 with different orientation of ligand within active site facing the heme. One poses of C27-steroid with C26 facing the heme with distance of 3.734 from the Fe were predominant.

The objective of this study was to examine the effects of steam flaking treatment of corn grains imported from USA and India on in vitro gas production, microbial growth and contents of aflatoxin and ochratoxin A. Each treatment was composed of total 4 treatments including (1) USCW (US com-whole type), (2) USCF (US corn-flaked type), (3) IDCW (India corn-whole type) and (4) IDCF (India orn-flaked type) with 4 replications 6 incubation times (3, 6, 9, 12, 18 and 24 hr). Mycotoxin (aflatoxin & ochratoxin A) contents in test corns tended to increase gradually with increasing logistics periods from the harbor, hopper, silo to processing line. The contents of aflatoxin in India corn (IDCW) and US corn (USCW) were 11.71 and 1.78 ppb, respectively when measured at the hopper. After steam flaking, both contents of aflatoxin in USCW and IDCW were 0.00 ppb. It means that Aspergillus flavus could be decreased by steam flaking. However, this trend was not observed in ochratoxin content. The gas production rate of USA corns (USCW & USCF) was significantly (p than whole corns (USCW & IDCW) after 3 hr incubation in in vitro experiment. pH value was optimally maintained for microbial growth during whole incubation times with the value of 6.05 to 6.54, and was not significantly different between treatments, but USCF was somewhat lower than other treatments. pH value decreased following 12 hr of incubation but gas production increased rapidly during the same period. In addition, in vitro microbial growth rates also increased with up to 18 hr of incubation period, thereafter experienced a decrease with extended incubation time. In conclusion, US corn was superior to India corn by origin based on the results of in vitro and mycotoxin contents. And steam flaking process of imported corns tended to decrease mycotoxin contents such as aflatoxin and ochratoxin A as well as improve in vitro gas production and microbial growth rates.

This study was conducted to investigate the effects of steam flaking of corn grains on in situ dry matter degradability in the rumen and contents of mycotoxins (aflatoxin, ochratoxin) during storage. Yellow dent corns imported from USA and India were flaked, and stored for 8 weeks under the standard temperature and pressure (STP; / 1 atm.). Experimental treatments were composed of four corn grains (untreated-USA corn, USCW; steam flaked-USA corn, USCF; untreated-India corn, IDCW; steam flaked-India corn, IDCF) with 4 replications according to 9 storage periods (0, 1, 2, 3, 4, 5, 6, 7, 8 week). Two ruminally cannulated Holstein bulls were used for in situ trial. Pathogen contamination trial was performed by comparing the mycotoxin contents in corns during storage periods. Dry matter disappearance rate in the rumen was about 3.0 to 44.1% higher (P

Development of an in situ technique for measuring electrochemical impedance spectra in real time during an electrochemical experiment is described. The technique is based on staircase voltammetry with relatively large step heights, in which a series of increasing potential steps are applied to an electrochemical system, and the resulting currents are sampled. The first derivatives of the currents thus obtained are then converted to ac current signals in frequency domain, and impedances are computed from them. To demonstrate the technique as a tool for studying the electrode/electrolyte interface during the electrochemical reaction, we chose an electrochemical oxidation reaction of aniline, whose reaction products have been known to continuously change the electrode surface due to the polymer film growth on its surface, and report a number of observations that would not have been obtained without such in situ experiments. A suggestion is also made on the use of staircase voltammetry for mechanistic studies on complex electrochemical reactions by simply varying the sampling time.