[Real-Time Stability Monitoring of Photonic Crystal Sensing System Based on Guided-Mode Resonance Effect].

The detection limit of antibody content has reached level of nanograms per milliliter due to high sensitivity and extremely narrow band of photonic crystal (PC) filter. The PC filter based on guided-mode resonance (GIR) effect can also be applied to detecting the molecular interactions. As the transducing element, one-dimensional PC filters transform biological information to photoelectric signal on optical spectrum analyzer (OSA). The main sensing performance is the change of peak-wavelength of PC filter. The sensing system using PC filter is restricted to the system stability which determines the effectiveness of detecting data. So in this paper, a detecting system we designed is briefly addressed. The morphology and the spectrum of PC filter we fabricated are tested. Considering the coupling light loss and integration of the system, noise signal in spectrum is going to affect the detecting results. To monitor the influence, realization of real-time monitoring the changes of the peak wavelength of PC filter is mainly illustrated. The monitoring is realized by transferring detecting data to computer in time and the results can represent the stability of the system. The program is compiled by Lab VIEW. In our experiment, the shift of 0. 25 nm of the peak wavelength caused by vibration of platform or unsteadiness of light source is within the sensitivity of the PC filter obtained by simulation, so we proposed this system we mentioned can be used in sensing most kind of bulk reagents.

Changes in proteins within germinating seeds of transgenic wheat with an antisense construct directed against the thioredoxin.

Thioredoxin h is closely related to germination of cereal seeds. The mechanism of transgenic wheat seeds with antisense trxs gene, which is responsible for low germination rate was studied through analyzing the changes in proteins of wheat seeds during germination. The antisense trxs could weaken the metabolism of wheat seeds by decreasing the quantity of proteins involved in metabolism, while chloroform-methanol (CM) protein fraction consisted mostly of some low molecular weight proteins (<20 kD). Compared with wild-type wheat seeds, the folding of glutenin in transgenic wheat ones was affected during the wheat maturating. Big glutenin macropolymers could be formed more easily in transgenic wheat seeds than in wild-type wheat ones. Therefore, the degradation speed of glutenin in transgenic wheat seeds was slower than that in wild-type wheat ones during seed germination. In addition, the degradation of some proteins in transgenic wheat embryos was also delayed during germination.

L-carnitine inhibits apoptotic DNA fragmentation induced by a new spin-labeled derivative of podophyllotoxin via caspase-3 in Raji cells.

L-carnitine (beta-hydroxy-trimethylaminobutyric acid) plays an essential metabolic role that consists of transferring the long chain fatty acids through the mitochondrial barrier, thus allowing their energy-yielding oxidation. GP7 (4-[4''-(2'', 2'', 6'', 6''-tetramethyl-l''-piperidinyloxy) amino] -4'-demethyl-epipodophyllotoxin) is a new spin-labeled derivative of podophyllotoxin semi-synthesized by our university. In this study, we examined the activity of L-carnitine in GP7-induced apoptosis in Burkitt's lymphoma cell line, Raji. GP7 induced time- and dose-dependent apoptotic DNA fragmentation accompanied by caspase-3 activation in Raji cells, and the kinetics of caspase-3 activation induced by GP7 was well correlated with that of apoptotic DNA fragmentation. L-carnitine treatment prevented GP7-induced caspase-3 activation, suppressed caspase-3 cleavage and abrogated GP7-induced apoptotic DNA fragmentation in Raji cells. Our findings suggest that L-carnitine is a potent anti-apoptotic agent to human lymphoma cells and may exert its anti-apoptotic effect via inhibition of caspase-3 activity in GP7-treated Raji cells.