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A new, accelerated design scheme for photoinitiators based on an advanced machine learning framework is studied. Design space for photoinitiators is set by over 120 unique oxime ester compounds synthesized and measured for their photosensitivity. Then, an automated machine learning algorithm is used for rapidly identifying the best quantitative structure–property relationship (QSPR) models among hundreds that are generated, ranked, and validated in an automated fashion to predict photosensitivity. Top-performing models are highly predictive with coefficients of determination of around 0.8 for compounds that are unknown to the models. Visual interpretation of the predictive models based on atom-site contributions offers a clear and intuitive direction to design new photoinitiators. Based on the machine learning-assisted analysis, three new oxime ester compounds were pushed for synthesis and further evaluation as novel photoinitiators. Experimental validation confirms high photosensitivity in all of the newly synthesized candidates. The work demonstrates the value of combining synthesis with the automated machine learning framework as a fast and reliable measure, which provides unbiased insights often hidden in high-dimensional data space.

Actinobacillus pleuropneumoniaeis the etiologic agent of porcine pleuropneumonia, a highly contagious pulmonary disease in pigs with major economic losses for pig producers worldwide. Whereas A. pleuropneumoniaeisolates are divided into 15 serotypes, the isolates secrete 4 types of exotoxins (ApxI, ApxII, ApxIII, and ApxIV), which are known as major virulence factors. In the current study, the ApxIA, ApxIIA, and ApxIIIAgenes were amplified and their recombinant proteins expressed in Escherichia coliM15 cells. The antigenicity of each recombinant protein was demonstrated by Western blot and enzyme-linked immunosorbent assay (ELISA) using sera from pigs vaccinated with a subunit vaccine. When ELISAs using the recombinant antigens were optimized and then applied to sera from 320 randomized pigs in Korea, an observed increase in seroprevalence was found among sows in comparison with weaned piglets and growing pigs, indicating an age-dependent seroprevalence. The results obtained in the study suggest that the developed ELISAs may be useful for A. pleuropneumoniaevaccination strategy as a screening tool for pig herds as well as for detection of specific antibodies to Apx exotoxins.

Adherence factors and enterotoxins are major virulence factors of enterotoxigenic Escherichia coli(ETEC). Antibiotics have been used frequently for the treatment and prevention of ETEC infection in piggeries worldwide, including Korea. Therefore, data on both virulence profiles and antibiotic resistance patterns are useful in the epidemiological study of ETEC. A total number of 198 E. colifield isolates were examined. The most prevalent pathotype was F1, followed by a combination of F1 and EAST1. All of the 71 isolates were resistant to more than 2 antibiotics used in a disk diffusion test, and 87.94% of the isolates were found to be resistant to more than 4 antibiotics. Investigations were also conducted to correlate the virulence gene profiles with antibiogram and pulsed-field gel electrophoresis (PFGE). Although a high degree of polymorphism was noted among strains having the same virulence patterns, the highest similarity pattern was observed carrying the same virulence profiles and similar antibiogram. Thus, investigation of both virulence profiles and antibiogram is essential to the epidemiological study of ETEC. Moreover, the PFGE method might be applicable as a tool to reveal genetic relatedness among E. colistrains from piggeries in Korea.

Catechins, components of green tea, reduce the incidence of cardiovascular diseases such as atherosclerosis. Angiotensin II (Ang II) is highly implicated in the proliferation of vascular smooth muscle cells (VSMC), resulting in atherosclerosis. The acting mechanisms of the catechins remain to be defined in the proliferation of VSMC induced by Ang II. Here we report that catechin, epicatechin (EC), epicatechingallate (ECG) or epigallocatechingallate (EGCG) significantly inhibits the Ang II-induced [3H]thymidine incorporation into the primary cultured rat aortic VSMC. Ang II increases the phosphorylation of the extracellular signal-regulated protein kinase 1/2 (ERK 1/2), c-jun-N-terminal kinase 1/2 (JNK 1/2), or p38 mitogen-activated protein kinases (MAPKs) and mRNA expression of c-jun and c-fos. The EGCG pretreatment inhibits the Ang II-induced phosphorylation of ERK 1/2, JNK 1/2, or p38 MAPK, and the expression of c-jun or c-fos mRNA. U0126, a MEK inhibitor, SP600125, a JNK inhibitor, or SB203580, a p38 inhibitor, attenuates the Ang II-induced [3H]thymidine incorporation into the VSMC. In conclusion, catechins inhibit the Ang II-stimulated VSMC proliferation via the inhibition of the Ang II-stimulated activation of MAPK and activator protein-1 signaling pathways. The antiproliferative effect of catechins may be associated with the reduced risk of cardiovascular diseases by the intake of green tea. Catechins may be useful in the development of prevention and therapeutics of vascular diseases.

3,4‐Di‐(2′‐hydroxyethoxy)‐4′‐nitrostilbene was prepared and condensed with terephthaloyl chloride, adipoyl chloride, and sebacoyl chloride to yield novel Y‐type polyesters containing NLO‐chromophore dioxynitrostilbenyl groups, which constituted parts of the polymer backbone. Polymers were found soluble in common organic solvents such as acetone and N,N‐dimethylformamide. They showed thermal stability up to 300 °C in thermogravimetric analysis with glass‐transition temperatures obtained from differential scanning calorimetry in the range 110–152 °C. The second harmonic generation (SHG) coefficients (d33) of poled polymer films at a 1064 cm−1 fundamental wavelength were around 3.51 × 10−8 esu. The dipole alignment exhibited high thermal stability even at 10 °C higher than the glass‐transition temperature, and there was no SHG decay below 120 °C for one of these polymers due to the partial main‐chain character of polymer structure, which was acceptable for NLO device applications. Copyright © 2005 Society of Chemical Industry

3,4‐Di‐(2′‐hydroxyethoxy)‐4′‐nitrostilbene (2) was prepared by the reaction of 2‐iodoethanol with 3,4‐dihydroxy‐4′‐nitrostilbene. Diol 2 was condensed with 2,4‐toluenediisocyanate, 3,3′‐dimethoxy‐4,4′‐biphenylenediisocyanate and 1,6‐hexamethylenediisocyanate to yield novel Y‐type polyurethanes 3–5 containing dioxynitrostilbene as a non‐linear optical (NLO)‐chromophore. Polymers 3–5 were soluble in common organic solvents, such as acetone and DMF. These polymers showed thermal stability up to 280 °C in TGA thermograms with Tg values in the range of 100–143 °C in DSC thermograms. The approximate lengths of aligned NLO‐chromophores of the polymers estimated from AFM images were around 2 nm. The SHG coefficients (d33) of poled polymer films were around 4.5 × 10−8 esu. Poled polymer films had improved temporal and long‐term thermal stability owing to the hydrogen bonding of urethane linkage and the main‐chain character of the polymer structure, which are acceptable for NLO device applications. Copyright © 2004 Society of Chemical Industry

2,4-Di-(2′,2′-dicyanovinyl)-1-(2′-vinyloxyethoxy)benzene and 2,4-di-(2′-carbomethoxy-2′-cyanovinyl)-1-(2′-vinyloxyethoxy)benzene were prepared by condensation of 4-(2′-vinyloxyethoxy)isophthaldehyde with malononitrile and methyl cyanoacetate, respectively. The two vinyl monomers were polymerized with boron trifluoride etherate as a cationic initiator to yield poly(vinyl ether)s containing two oxybenzylidenemalononitrile and oxybenzylidenecyanoacetate groups, which are effective chromophores for second-order nonlinear optical applications. These polymers were soluble in common organic solvents such as acetone and dimethyl sulforide. They showed thermal stabilities up to 300 °C from thermogravimetric analysis (TGA), with differential scanning calorimeter (DSC) thermograms giving T_g values in the range 73-87 °C. The second harmonic generation (SHG) coefficients (d₃₃) of poled polymer films were around 1.8 × 10⁻⁹ esu, and these polymers showed good long-term thermal stability for 60 days at room temperature, which is acceptable for nonlinear optical (NLO) device applications. Copyright © 2004 Society of Chemical Industry

Resveratrol has been shown to possess antioxidant and anticancer activities, but little is known on the effect of resveratrol derivatives. Recently we have isolated resveratrol and its dimers and trimers from peony (Paeonia lactiflora) seeds, and reported their strong antioxidant and cytotoxic activity. In the present study, we have evaluated cellular effects of resveratrol derivatives; viniferin, gnetin H, and suffruticosol B on the proliferation and apoptosis in HL-60 cells in vitro. All resveratrol and its derivatives reduced viability of HL-60 cells in a dose-dependent manner with their IC50values of 20-90 µM. Ascending orders of IC50values were suffruticosol B, gnetin H, viniferin and resveratrol respectively. HL-60 cells treated with the four stilbenes exhibited the distinct morphological changes characteristics of cell apoptosis such as chromatin condensation, apoptotic bodies, and DNA fragmentations. A time-dependent histogram of the cellular DNA analyzed by flow cytometry revealed a rapid increase in subdiploid cells and a concomitant decrease in diploid cells exposed to 100 µM resveratrol for 0-24 h. Cells treated with 25 µM of resveratrol, viniferin, gnetin H, and suffruticosol B for 24 h resulted in increment of sub-G1 population by 51, 5, 11 and 59%, respectively. Treatment of cells with 0-20 µM resveratrol for 5 h produced a concentration-dependent decrease in cytochrome P450 (CYP) 1B1 mRNA levels. Suffruticosol B also suppressed CYP1B1 gene expression. These results demonstrated that resveratrol oligomers also strongly suppressed HL-60 cell proliferation, and induced DNA damage. In addition, CYP1B1 gene supression may suggest an involvement in the resveratrol-induced apoptosis in HL-60 cells.

It has been suggested that various vasoactive substances and growth factors are involved in left-ventricular myocardial hypertrophy and failure. However, limited data are available on the role of humoral factors involved in right-ventricular (RV) hypertrophy. To examine implications of humoral factors involved in the development of RV hypertrophy, altered mRNA expressions of the renin–angiotensin system (RAS), transforming growth factor (TGF)- β1, endothelin-1 and nitric oxide synthase (NOS) were investigated in monocrotaline (MCT)-induced pulmonary hypertensive rats. Male Sprague–Dawley rats were treated with MCT (60 mg kg−1, s.c.) to induce a selective RV hypertrophy. Three or 6 weeks later, the heart was removed to determine the tissue gene expressions in the right and left ventricles (LV) by reverse transcription-polymerase chain reaction due to the relatively low mRNA expression levels of the RAS components in the ventricle (n= 6 in each group). MCT-treated rats showed a selective RV hypertrophy at weeks 3 and 6 of MCT treatment (the ratios of RV/body weight were 1.5- and 2.2-fold higher than the controls, respectively). Levels of renin and angiotensinogen mRNAs in the hypertrophied RV were significantly increased at both weeks 3 and 6 of MCT treatment. The angiotensin-converting enzyme mRNA level also increased approximately 2-fold at week 3. In contrast, RAS component mRNAs in the LV were not significantly altered by MCT treatment, except for a 1.8-fold increase of angiotensinogen mRNA at week 3. The expression of Ang II receptors, either AT1Aor AT1B, was not significantly altered by MCT treatment. Furthermore, MCT treatment significantly increased TGF-β1mRNA levels in the RV at weeks 3 and 6, while it did not significantly affect them in the LV. Endothelin-1 mRNA expression was significantly higher in the RV at week 3, but was normalized at week 6 of MCT treatment. The gene expression of the endothelial constitutive isoform of NOS was increased in the RV at weeks 3 and 6, but not in the LV. Elevated gene expression of local RAS, along with TGF- β1and endothelin-1 in the present study may contribute to the development of RV hypertrophy. On the contrary, an enhanced ecNOS expression may be a mechanism counteracting the hypertrophy.

We formulate a pair of multiobjective nonlinear generalized symmetric dual variational problems involving vector-valued functions which unify the Wolfe and Mond–Weir models. For a special case, our problems become the symmetric dual pair of D. S. Kim and W. J. Lee (1998,J. Math. Anal. Appl.218, 34–48). Under invexity assumptions, we establish weak, strong, and converse duality theorems for our variational problems by using the concept of efficiency. Also, we give the static case of our multiobjective generalized symmetric duality results. Several known results are obtained as special cases.

We formulate a pair of multiobjective nonlinear symmetric dual variational problems. For the single objective problems our problems become the symmetric dual pair of I. Smart and B. Mond (J. Math. Anal. Appl.152, 1990, 536–545). Under invexity assumptions, we establish the weak, strong, converse, and self duality theorems for our variational problems by using the concept of efficiency. Also, we give the static case of our symmetric duality results.

For Abstract see ChemInform Abstract in Full Text.

For Abstract see ChemInform Abstract in Full Text.