Identification of binding domains in the sodium channel Na(V)1.8 intracellular N-terminal region and annexin II light chain p11

In human brain the Aβ peptide is produced mainly by neurons and the overexpression of amyloid precursor protein (APP) that involves an increase in Aβ secretion, has been observed in some areas of the Alzheimer's disease patients brain. We have generated two stably transfected human neuroblastoma lines which overexpress APP; both of them secreted Aβ and showed morphological changes and cell death with apoptotic program characteristics. Interestingly, coculture experiments with the untransfected human neuroblastoma cell line showed that the Aβ peptide was not responsible for the death in those cell lines; additionally, we indicate that upon cell death, Aβ peptide is secreted into cell medium.     

Keratocan-deficient mice display alterations in corneal structure

Keratocan (Kera) is a cornea-specific keratan sulfate proteoglycan (KSPG) in the adult vertebrate eye. It belongs to the small leucine-rich proteoglycan (SLRP) gene family and is one of the major components of extracellular KSPG in the vertebrate corneal stroma. The Kera gene is expressed in ocular surface tissues including cornea and eyelids during morphogenesis. Corneal KSPGs play a pivotal role in matrix assembly, which is accountable for corneal transparency. In humans, mutations of the KERA gene are associated with cornea plana (CNA2) that manifests decreases in vision acuity due to the flattened forward convex curvature of cornea. To investigate the biological role of the Kera gene and to establish an animal model for corneal plana, we generated Kera knockout mice via gene targeting. Northern and Western blotting and immunohistochemical analysis showed that no Kera mRNA or keratocan protein was detected in the Kera-/- cornea. The expression levels of other SLRP members including lumican, decorin, and fibromodulin were not altered in the Kera-/- cornea as compared with that of the wild-type littermates. Mice lacking keratocan have normal corneal transparency at the age of 12 months. However, they have a thinner corneal stroma and a narrower cornea-iris angle of the anterior segment in comparison to the wild-type littermates. As demonstrated by transmission electron microscopy, Kera-/- mice have larger stromal fibril diameters and less organized packing of collagen fibrils in stroma than those of wild type. Taken together, our results showed that ablation of the Kera gene resulted in subtle structural alterations of collagenous matrix and did not perturb the expression of other SLRPs in cornea. Keratocan thus plays a unique role in maintaining the appropriate corneal shape to ensure normal vision.     

Biochemical Changes in Seed of Pinus radiata D. Don during Stratification

Stratification at 0 °C accelerates subsequent germinationof seed of Pinus radiata D. Don when transferred to 25 °C;the effect of low temperature is on the megagametophyte, notthe embryo. Organic acids, sucrose, and organic phosphates accumulatein the seed during stratification but lipase and invertase havelow activities which do not increase during treatment at 0 °C.We conclude that this accumulation of metabolites underliesthe increase in rate of germination of stratified seed. Treatingseeds at 0 °C rather than 5 °C separates effects dueto stratification and growth.     

Decontamination ofFusarium mycotoxins,nivalenol, deoxynivalenol,and zearalenone,in barley by the polishing process

Korean dehusked and unhusked barley naturally contaminated withFusarium mycotoxins were polished using a Satake Grain Testing Mill. The pearled barley and bran fractions with different degrees of polishing were analyzed for nivalenol (NIV) and deoxynivalenol (DON) by gas chromatography with an electron capture detector, and for zearalenone (ZEN) by high-performance liquid chromatography with a fluorescence detector. NIV was detected in all the pearled barley fractions, but DON and ZEN were not detected in ≥27 % pearled barley fractions from dehusked barley and ≥36% pearled barley fractions from unhusked barley. However, for all degrees of polishing, NIV, DON, and ZEN were detected in bran fractions. The levels of NIV, DON, and ZEN in the bran fractions increased several fold over the original barley. Polishing was effective in removing DON and ZEN from the naturally contaminated barley, but not NIV.     

夜蛾趋光特性的研究:棉铃虫和烟青虫成虫对单色光的反应

从333毫微米到656毫微米的波长范围内,棉铃虫和烟青虫成虫对于13种单色光的趋光特性极其相似。根据波长选择实验获得的反应曲线有三个峰,最高峰值波长均为333毫微米。对于这种波长的反应数量比对365毫微米多出2.5—3.4倍。甚至当365毫微米的辐射强度升高为333毫微米的2倍时也不能缩小这种差异。选择特性不因羽化后的天数增加而发生改变。