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541.
We examined the lateral flow strip assay for identifying unauthorized genetically modified (GM) rice. The GM rice expresses the Bacillus thuringiensis (Bt) toxin, CryIAc protein, which confers tolerance to insects. The recombinant CryIAc protein was prepared from the inclusion bodies of an E. coli. strain into which the CryIAc gene had been inserted, using gel filtration chromatography. The lateral flow strip assay for the identification of GM cotton which also expresses CryIAc protein, was applied to unpolished rice and polished rice spiked with recombinant CryIAc protein. The spiked recombinant CryIAc protein was clearly detected at the level of 0.012 microg/g in both the unpolished and polished rice. After loading of the extract on the strip, a 60 -minute stand time is necessary to clearly detect CryIAc protein. The detection limit was approximately 12 ng CryIAc protein per gram of rice. These results suggest that the lateral flow strip assay for GM cotton can be used to detect CryIAc protein expressed in GM rice.  相似文献   
542.
The pathogenesis of diabetic vascular complications involves the formation of advanced glycation end-products (AGEs). AGEs accumulate slowly in the body with age and more rapidly in individuals with diabetes mellitus. An abnormally elevated blood glucose level in diabetes mellitus causes the formation of AGEs. Also, oxidative reactions contribute significantly to the formation of AGEs. The antioxidant flavonoids, quercetin, isoquercitrin, hyperin and cacticin from plants, decrease the formation of AGEs. This activity was examined using an in vitro glycation reaction. Of the tested compounds, isoquercitrin and hyperin showed a strong inhibitory activity against the formation of AGEs. These compounds showed inhibitory activities that were more potent than the positive control, aminoguanidine. These results suggest that isoquercitrin and hyperin may be promising agents to treat glycation-associated diseases.  相似文献   
543.
Intercalation into 1D transition metal trichalcogenides (TMTs) in which fibers are bonded by a weak van der Waals force can be expected to create various intercalation compounds and develop unique physical properties according to the combination of the host materials and guest ions. However, structural changes via intercalation into 1D TMTs are not as simple as those in 2D transition metal dichalcogenides (TMDs) and are still not understood comprehensively. ZrTe3: a typical compound with a 1D trigonal prismatic structure, belongs to TMTs. Herein, through the Ag introduction to ZrTe3 via solid-state intercalation, a novel crystal phase with a 1D octahedral structure and a quasi-amorphous (QA) phase during the structural transition are discovered; the QA phase is a novel state of matter in which long-range order is lost while retaining 1D order. Based on the Ag concentration, the transport properties are flexibly modulated from superconductivity to semiconductivity. Density functional theory calculations indicate the attraction between Ag ions and the pair diffusion due to their attraction. Furthermore, judging the attraction or repulsion between guest ions predicts whether to induce a QA phase or simple lattice expansion like the intercalation into 2D TMDs.  相似文献   
544.
The complex [Ir(cod)Cl]2/DPPF or rac‐BINAP is an efficient catalyst for the [2+2+2] cycloaddition of α,ω‐diynes with cyanamides. A wide range of cyanamides derived from secondary amines are good coupling partners for α,ω‐diynes. The reaction of unsymmetrical α,ω‐diynes possessing two different internal alkyne moieties with cyanamides is regioselective. A competitive experiment showed that cyanamide is more reactive than nitrile. This higher reactivity of cyanamide than nitrile was analyzed based on density functional theory (DFT) calculations at the B3LYP level.

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