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Abstract  

By substututing99Mo for the Mo in the reconstituted MoFe protein, the nuclear quadrupole interactions (NQI) of99Mo have been measured using the perturbed angular correlations (PAC). Two well-defined electric quadrupole interaction parameters have been observed. The configuration of the M-Center of the MoFe protein is identified by the quadrupole couplign constant Q1(412(9)MHz) and the asymmetry parameter 1(0.49(5)). Other parameters, VQ2(1939(13)MHz) and 1(0.90(1)), may correspond to a deformation M—Center of MoFe protein.

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Chemokine a nd antibody response profiles were investigated in children and adults with severe or uncomplicated Plasmodium falciparum malaria; the aim was to reveal which profiles are associated with severe disease, as often seen in nonimmune children, or with mild and uncomplicated disease, as seen in semi-immune adults. Blood samples were obtained from children under 5 years of age as well as adults with falciparum malaria. Classification of malaria was performed according to parasite densities and hemoglobin concentrations. Plasma levels of chemokines (IL-8, IP-10, MCP-4, TARC, PARC, MIP-1δ, eotaxins) were quantified, and antibody responses (IgE, IgG1, and IgG4) to P. falciparum, Entamoeba histolytica-specific antigen, and mite allergen extracts were determined. In children with severe malaria proinflammatory, IL-8, IP10, MIP-1δ, and LARC were at highly elevated levels, suggesting an association with severe disease. In contrast, the Th2-type chemokines TARC, PARC, and eotaxin-2 attained in children the same levels as in adults suggesting the evolution of immune regulatory components. In children with severe malaria, an elevated IgG1 and IgE reactivity to mite allergens and intestinal protozoan parasites was observed. In conclusion, exacerbated proinflammatory chemokines together with IgE responses to mite allergens or E. histolytica-specific antigen extract were observed in children with severe falciparum malaria.

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Abstract  

The damage in the pup rat brain with low-level mercury exposure, and the concentration variation of trace elements in the rat hippocampus was determined by synchrotron radiation X-ray fluorescence technique (SRXRF). Meanwhile, the levels and activities of glutathione (GSH), glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), catalase (CAT) and malondialdehyde (MDA) in the hippocampus were also measured. The results showed that the low dose of inorganic mercury prenatal and postnatal exposure could lead to the significant increase of both copper and zinc contents and remarkable decrease of iron content in pup rat brain. Compared to the control group, the activities of antioxidant enzymes such as GSH-Px, SOD, the contents of GSH and MDA in the pup rat hippocampus of mercury-exposed group fell down obviously.

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Abstract  

To investigate the effects of lanthanum exposure on regional distribution of inorganic elements in rat brain. Wistar rats were exposed to lanthanum chloride through oral administration at 0, 0.1, 2, and 40 mg/kg concentration for 6 months. The elements such as Cl, K, Ca, Fe, Cu, and Zn were identified in the brain slices by synchrotron radiation X-ray fluorescence (SRXRF) analysis. Differences of brain elemental distributions were noticed. Cl, Ca, and Zn were primarily concentrated in hippocampus of the controls. With the increase of the lanthanum dosage, the Ca and Zn levels significantly decreased, while the Cu levels significantly elevated in cortex, hippocampus and thalamus. Our results suggest that subchronic lanthanum exposure in rats appears to change elemental distributions in brain.

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Abstract  

The thermal mechanical properties and degradation behaviors were studied on fibers prepared from two high-performance, heterocyclic polymers, poly(p-phenylenebenzobisthiazole) (PBZT) and poly(p-phenylenebenzobisoxazole) (PBZO). Our research demonstrated that these two fibers exhibited excellent mechanical properties and outstanding thermal and thermo-oxidative stability. Their long-term mechanical tensile performance at high temperatures was found to be critically associated with the stability of the C—O or C—S linkage at the heterocyclic rings on these polymers' backbones. PBZO fibers with the C—O linkages displayed substantially higher thermal stability compared to PBZT containing C—S linkages. High resolution pyrolysis-gas chromatography/mass spectrometry provided the information of the pyrolyzates' compositions and distributions as well as their relationships with the structures of PBZT and PBZO. Based on the analysis of the compositions and distributions of all pyrolyzates at different temperatures, it was found that the thermal degradation mechanisms for both of these heterocyclic polymers were identical. Kevlar®-49 fibers were also studied under the same experimental conditions in order to make a comparison of thermo-oxidative stability and long-term mechanical performance at high temperatures with PBZO and PBZT fibers. The data of two high-performance aromatic polyimide fibers were also included as references.

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Abstract  

Positron annihilation lifetime (PAL) experiments are performed in polycarbonate (PC) exposed to CO2 and He gases as a function of time and pressure. In PC/CO2 systems, hole size and fraction reduced from PAL data increase as a function of CO2 pressure and exposure time. Significant hysteresis in positron lifetime data is observed during CO2 abasorption/desorption. In PC/He systems, no variation is observed. Hole size distribution in the CO2-exposed polymers is found to be significantly broader than in unexposed samples. The high sensitivity of PAL results to CO2 exposure of PC is thought to relate to the microstructural changes in the polymer matrix, such as penetrant plasticization, gas hydrostatic pressure effect, and molecular filling and creation of holes.

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Cereal Research Communications
Authors: D. Huang, H. Zhang, M. Tar, Y. Zhang, F. Ni, J. Ren, D. Fu, L. Purnhauser, and J. Wu

Stripe or yellow rust (Yr), caused by Puccinia striiformis Westend. (Pst), is one of the most important wheat diseases worldwide. New aggressive Pst races can spread quickly, even between countries and continents. To identify and exploit stripe rust resistance genes, breeders must characterize first the Pst resistance and genotypes of their cultivars. To find new sources of resistances it is important to study how wheat varieties respond to Pst races that predominate in other continents. In this study we evaluated stripe rust resistance in 53 Hungarian winter wheat cultivars in China. Twenty-four cultivars (45.3%) had all stage resistance (ASR) and 1 (1.9%) had adult-plant resistance (APR), based on seedling tests in growth chambers and adult-plant tests in fields. We molecularly genotyped six Yr resistance genes: Yr5, Yr10, Yr15, Yr17, Yr18, and Yr36. Yr18, an APR gene, was present alone in five cultivars, and in ‘GK Kapos’, that also had seedling resistance. The other five Yr genes were absent in all cultivars tested.

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Journal of Thermal Analysis and Calorimetry
Authors: F. Xu, L. Sun, J. Zhang, Y. Qi, L. Yang, H. Ru, C. Wang, X. Meng, X. Lan, Q. Jiao, and F. Huang

Abstract  

Heat capacities of the carbon nanotubes (CNTs) with different sizes have been measured by modulated temperature differential scanning calorimetry (MDSC) and reported for the first time. The results indicated the values of C p increased with shortening length of CNTs when the diameters of CNTs were between 60 and 100 nm. However, the values of C p of CNTs were not affected by their diameter when the lengths of CNTs were 1–2 um, or not affected by the length of CNTs when their diameters were below 10 nm. The thermal stabilities of the CNTs have been studied by TG-DTG-DSC. The results of TG-DTG showed that thermal stabilities of CNTs were enhanced with their diameters increase. With lengths increase, the thermal stabilities of CNTs increased when their diameters were between 60 and 100 nm, but there is a slight decrease when their diameters were less than 60 nm. The further DSC analyses showed both released heat and T onset increased with the increase of CNTs diameters, which confirms the consistency of the results from both TG-DTG and DSC on CNTs thermal stability.

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Shuganjieyu (SGJY) capsule is a classical formula widely used in Chinese clinical application. In this paper, an ultra-performance liquid chromatography coupled with electrospray ionization and ion trap mass spectrometry has been established to separate and identify the chemical constituents of SGJY and the multiple constituents of SGJY in rats. The chromatographic separation was performed on a C18 RRHD column (150 × 2.1 mm, 1.8 μm), while 0.1% formic acid–water and 0.1% formic acid–acetonitrile was used as mobile phase. Mass spectral data were acquired in both positive and negative modes. On the basis of the characteristic retention time (R t) and mass spectral data with those of reference standards and relevant references, 73 constituents from the SGJY and 15 ingredients including 10 original constituents and 5 metabolites from the rat plasma after oral administration of SGJY were identified or tentatively characterized. This study provided helpful chemical information for further pharmacology and active mechanism research on SGJY.

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