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Aberrant expression of fucose or sialic acid containing glycans is prevalent in various cancers, including breast cancer. The addition of fucose and sialic acid to glycans is mediated by fucosyl transferases (FUTs) and sialyl transferases (STs), respectively. To explore the roles of these FUTs and STs in breast cancer, we collected 123 paired breast cancer specimens (tumor tissue and non-tumor tissue) and determined the RNA expression levels of 13 FUTs (FUT1-13) and 13 STs (ST3Gal1-6, ST6Gal1, ST6GalNAc1-4, ST6GalNAc6, ST8Sia1 and ST8Sia4) by q-PCR. The expression of 10 FUTs and 10 STs is significantly higher in tumor tissue than in non-tumor tissue by 1.2-4.09 folds. Notably, expression of FUT1 and ST3Gal1 appeared to be highest in triple negative subtype. Further multivariate Cox regression analysis showed a significant correlation between higher hazard ratios (HRs) for five-year relapse-free survival (RFS) and higher ST3Gal1 expression (N = 16, HR = 2.54, p = 0.02) or lower ST3Gal3 expression (N = 88, HR = 3.44, p < 0.001). As to the joint effects of high expression of ST3Gal1 and low expression of ST3Gal3 (N = 10) compared with low expression of ST3Gal1 and high expression of ST3Gal3 (N = 82), the HR was 5.5 (95% CI = 2.16-14.02, p = 0.0004) for RFS. The two gene additive model displayed a statistically significant HR of 2.33 for RFS (95% CI = 1.48-3.69, p = 0.0003). These results suggest that FUTs and STs play important roles in tumor progression. Citation Format: Yu AL, Liao K-H, Chang C-H, Lin Y-C, Fan T-C, Hung J-T, Yeo H-L, Lin R-J, Yu J-C. Expression levels of sialyl transfereases and fucosyl transferases in breast cancer and their prognostic significance. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P1-08-05.

In power transistor models, it is very important that device capacitances are modelled accurately so that switching losses, EMI filter requirements and gate timing requirements of the converter can be accurately determined. In this paper, a modelling technique utilizing modified sigmoid functions to describe the device capacitances is applied on a GaN HEMT and a silicon MOSFET to develop their corresponding SPICE models. Comparison of switching energies of the transistors under slow-switching conditions suggest that the technique is suitable for modelling both types of transistors. The developed model for the GaN HEMT is also shown to simulate faster than the manufacturer's model under fast switching conditions.

Objectives We have investigated the efficacy of using quantitative fluorescent polymerase chain reaction (QF-PCR) for the prenatal recognition of aneuploidy in chromosomes 13, 18, 21, X and Y. A total of 1115 samples, from mainly southeast Asian patients, were analysed and compared in a blind trial to the results previously obtained cytogenetically. Methods A multiplex PCR involving 15 short tandem repeat (STR) sequences was used. The probability of two or more of these markers being informative was calculated, and this required the multiplex PCR to be modified. Results The QF-PCR and previous cytogenetic results concurred, except for two products of conception (POC). One of these may be a case of complete uniparental disomy that was not recognized cytogenetically. The other was tetraploid, and as such appeared normal using QF-PCR. A mosaic trisomy 18 was correctly identified. The population sample was of a mainly Chinese, ethnic origin, and the allele frequency, size and heterozygosity appeared more restricted than the population groups analysed hitherto. Conclusion The QF-PCR methodology is an efficient cost-effective method of screening for major chromosome aneuploidy, and, for certain referral categories, could be used alone. It also appears to be applicable to patients of different ethnic origins. Copyright © 2004 John Wiley & Sons, Ltd.

The preparation of ethyl 4-ethoxy-2-methylcyclohexa-1,3-diene-1-carboxyate, ethyl 4-isopropoxy- 2-methylcyclohexa-1,3-diene-1-carboxylate, t-butyl 4-isopropoxy-2-methylcyclohexa-1,3-diene-1- carboxylate, ethyl 4-(t-butylcarbonyloxy)-2-methylcyclohexa-1,3-diene-1-carboxylate, and t-butyI 4-(t-butylcarbonyloxy)-2-methylcyclohexa-1,3-diene-1-carboxylate from Hagemann's ester and its t-butyl analogue in the presence of diethyl or diisopropyl sulfates and sodium hydride in dimethyl sulfoxide, or pivaloyl chloride and N,N,N',N'-tetramethylethylenediamine in tetrahydrofuran is described. The foregoing dienol ethers and esters are smoothly deprotonated by lithium diisopropyl- amide in tetrahydrofuran at -78" to give the corresponding ester dienolates, which react regio- specifically with a number of electrophiles, either a or y to the alkoxycarbonyl group of the dienol ether or ester. A number of the products, which are generally obtained in good yields, have been hydrolysed to Hagemann's ester derivatives substituted exclusively at C1.