Cyanocobalamin (CNCbl), a kind of vitamin B12 (cobalamin, Cbl), which has a special binding capability to rapid dividing cells and proliferating tissue, especially tumors, has been modified and labeled by 99mTc. The optimal labeling condition was determined, and the biodistribution of 99mTc-DTPA-b-CNCbl both in normal mice and TA2 mice bearing MA891 mammary tumors were studied. 99mTc-DTPA-b-CNCbl showed low uptake and rapid clearance in nontarget tissues, and renal excretion. About 40% of uptake at 1 hour remained in the tumor at 12 hours p.i. The satisfying ratio of T/NT was acquired at 6 hours p.i.
Authors:X.L. Liu, B.Y. Lu, C.Y. Wang, Y.J. Wang, H. Zhang, Z.R. Tian, and W.Q. Ji
The aphid Sitobion avenae F. is one of the most harmful pests of wheat growth in the world. A primary field screening test was carried out to evaluate the S. avenae resistance of 527 wheat landraces from Shaanxi. The results indicated that 25 accessions (4.74%) were resistant to S. avenae in the three consecutive seasons, of which accession S849 was highly resistant, and seven accessions were moderately resistant. The majority of S. avenae resistant accessions come from Qinling Mountains. Then, the genetic variability of a set of 33 accessions (25 S. avenae resistant and 8 S. avenae susceptible) originating from Qinling Mountains have been assessed by 20 morphological traits and 99 simple sequence repeat markers (SSRs). Morphological traits and SSRs displayed a high level of genetic diversity within 33 accessions. The clustering of the accessions based on morphological traits and SSR markers showed significant discrepancy according to the geographical distribution, resistance to S. avenae and species of accessions. The highly and moderately resistant landrace accessions were collected from the middle and the east part of Qinling Mountains with similar morphology characters, for example slender leaves with wax, lower leaf area, and high ear density. These S. avenae resistant landraces can be used in wheat aphid resistance breeding as valuable resources.
Authors:B. Chen, L.-W. Li, Y.-J. Lin, Z.-H. Wang, and G.-D. Lu
Rice sheath blight, caused by Rhizoctonia solani, is the most serious disease in the southern rice producing regions of China. The use of resistant varieties is the most economic strategy to control the disease. In this paper, a seedling inoculation method was used to evaluate rice germplasm resources for resistance to sheath blight. A total of 363 rice varieties were evaluated with a set of R. solani isolates. The results indicated that the rice varieties generally lacked resistance to R. solani, and no highly resistant/immune (HR) variety was found. However, two varieties displayed clear resistance (R) and 37 showed moderate resistance (MR) to the fungus. Overall, hybrid rice varieties have better resistance than conventional rice varieties, and among hybrid rice varieties, those with the II-32A sterile line genetic background were the most resistant. The results also indicated significant interactions between rice varieties and pathogen isolates, suggesting that an understanding of local R. solani populations is needed when recommending varieties to local growers.
The heat capacities of chrysanthemic acid in the temperature range from 80 to 400 K were measured with a precise automatic
adiabatic calorimeter. The chrysanthemic acid sample was prepared with the purity of 0.9855 mole fraction. A solid-liquid
fusion phase transition was observed in the experimental temperature range. The melting point, Tm, enthalpy and entropy of fusion, ΔfusHm, ΔfusSm, were determined to be 390.7410.002 K, 14.510.13 kJ mol-1, 37.130.34 J mol-1 K-1, respectively. The thermodynamic functions of chrysanthemic acid, H(T)-H(298.15), S(T)-S(298.15) and G(T)-G(298.15) were reported with a temperature interval of 5 K. The TG analysis under the heating rate of 10 K min-1 confirmed that the thermal decomposition of the sample starts at ca. 410 K and terminates at ca. 471 K. The maximum decomposition
rate was obtained at 466 K. The purity of the sample was determined by a fractional melting method.
Authors:M. Lu, B. Wang, Zh. Li, Y. Fei, L. Wei, and Sh. Gao
Antifreeze protein (AFP) can lower the freezing point by inhibiting the growth of ice crystals. In this article, the thermal
hysteresis activity (THA) of a plant AFP was measured with differential scanning calorimetry (DSC). As is shown, when the
amount of ice in the sample was less than 5% THA of this AFP reached as high as 0.35°C. The secondary structure of this AFP
was studied with circular dichroism (CD). The CD spectrum from 195to 240 nm indicated a well-defined secondary structure consisting
11% α-helix, 34%antiparallel β-sheet and 55% random coil.
Authors:Z.-C. Tan, B. Xue, S.-W. Lu, S.-H. Meng, X.-H. Yuan, and Y.-J. Song
The heat capacities of fenpropathrin in the temperature range from 80 to 400 K were measured with a precise automatic adiabatic calorimeter. The fenpropathrin sample was prepared with the purity of 0.9916 mole fraction. A solid—liquid fusion phase transition was observed in the experimental temperature range. The melting point, Tm, enthalpy and entropy of fusion,
fusSm, were determined to be 322.48±0.01 K, 18.57±0.29 kJ mol–1 and 57.59±1.01 J mol–1 K–1, respectively. The thermodynamic functions of fenpropathrin, H(T)—H(298.15), S(T)—S(298.15) and G(T)—G(298.15), were reported with a temperature interval of 5 K. The TG analysis under the heating rate of 10 K min–1 confirmed that the thermal decomposition of the sample starts at ca. 450 K and terminates at ca. 575 K. The maximum decomposition rate was obtained at 558 K. The purity of the sample was determined by a fractional melting method.