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Pristine graphene is fairly inert chemically, and as such, most application-driven studies use graphene oxide, or reduced graphene oxide. Using substrates to modulate the reactivity of graphene represents a unique strategy in the covalent functionalization of this otherwise fairly inert material. It was found that the reactivity of pristine graphene towards perfluorophenyl azide (PFPA) can be enhanced by a metal substrate on which graphene is supported. Results on the extent of functionalization, defect density, and reaction kinetics all show that graphene supported on Ni (G/Ni) has the highest reactivity toward PFPA, followed by G/Cu and then G/silicon wafer. DFT calculations suggest that the metal substrate stabilizes the physisorbed nitrene through enhanced electron transfer to the singlet nitrene from the graphene surface assisted by the electron rich metal substrate. The G/Ni substantially stabilizes the singlet nitrene relative to G/Cu and the free-standing graphene. The product structure is also predicted to be substrate dependent. These findings open up opportunities to enhance the reactivity of pristine graphene simply through the selection of the substrate. This also represents a new and powerful approach to increasing the reactivity of singlet nitrenes through direct electronic communication with graphene.

There are a limited number of validated questionnaires available for use in the clinical screening for allergic rhinitis (AR) in children ≤3 years old. We developed a novel self-reported questionnaire and assessed its accuracy and reliability.After establishing a pool of items, which were screened by experts, the Young Children Allergic Rhinitis Questionnaire (YCAR-Q) was administered to a birth cohort in the Shunyi District (Beijing, China). The electronic version of the YCAR-Q was distributed through the online community. Children were invited to visit a physician for examination. The diagnostic criteria included symptoms, physical examination findings, and specific serum immunoglobulin E tests. Each item on the questionnaire was evaluated, and the questionnaire's internal consistency, content validity, criterion-related validity, and diagnostic accuracy were assessed.The six-item YCAR-Q was distributed to 7423 parents, and 3037 valid questionnaires were recovered. In total, 1521 children visited a physician for examination, of which 82 were found to have AR. In terms of internal consistency, Cronbach's coefficient was 0.777 and all six questionnaire items were retained. The average scale-level content validity index value was 1. The area under the curve was 0.759. The total scores ranged from 0 to 6, and the cutoff value for diagnosing AR was 3, with a sensitivity of 68.29% and a specificity of 76.58%.This cross-sectional study indicated that the YCAR-Q could detect AR in children ≤3 years old. This brief and simple test may be used effectively in clinical practice.

BACKGROUND The mechanism of epithelial to mesenchymal transition (EMT) could be adopted by tumor cells for migration and invasion. We have reported that ARCaPE human prostate cancer cells undergo EMT-like changes during xenograft growth in athymic mice. METHODS In this report, we assessed the extent of EMT by tracking changes in cloned ARCaPE cells expressing red fluorescence protein during successive orthotopic prostate tumor formation. Cancer cells with stromal-like morphology were isolated and examined for EMT-like changes. RESULTS EMT-like morphologic and expression changes were detected after one round of in vivo tumor formation. Importantly, when recovered tumor cells were used in second round xenograft tumor formation, a large fraction of ARCaPE cells showed drastic EMT-like changes, with markedly enlarged cell size and divergent cell shapes similar to those of mesenchymal stromal cells. The morphologic change was accompanied by increased growth and metastasis, as tumor incidence increased while red fluorescent tumor cells could be detected from circulating blood, bone marrow, peritoneal ascites, and lung of the tumor-bearing mice. Recovered clones from these samples had lost epithelial markers but many showed activated stromal marker vimentin expression. The EMT appeared permanent since the newly acquired morphology was sustained after continuous passages. CONCLUSIONS Results from this study demonstrate that through interaction with the host tumor microenvironment, cancer cells acquire cellular plasticity. During xenograft tumor formation and metastasis, a single clone of cancer cells could yield a heterogeneous population, with a substantial number of tumor cells adopting mesenchymal stroma-like phenotypes. Prostate 70: 518–528, 2010. © 2009 Wiley-Liss, Inc.

A study was conducted to determine the effects of graded levels of dietary inclusion of a cysteamine (Cs) preparation on growth performance, carcass quality, plasma hormone levels, gastric pH and occurrence of gastric ulcer in finishing pigs. A total of 384 Landrace × Large White finishing pigs, (192 gilts and 192 barrows) with an average initial body weight of 66.05 ± 0.623kg (mean ± SEM) were randomly divided into 24 floor pens, with eight gilts and eight barrows in each pen (9.2m 2 )a s one experimental unit. The 24 pens of pigs were randomly allocated to one of three diets: (1) a maize/soybean meal basal diet; (2) the basal diet plus 30mgCskg −1 diet; and (3) the basal diet plus 50mgCskg −1 diet. Dietary supplementation of Cs had quadratic effects (P 0.05) on plasma growth hormone, insulin and T4 levels. There were no apparent pathological changes seen in the stomach mucosa of pigs fed at 30mgCskg −1 compared with the control diet. It is concluded that a low dose of dietary inclusion of Cs at 30mgkg −1 can improve growth performance and carcass quality without adverse effects on the stomach in finishing pigs.  2005 Society of Chemical Industry

This study investigated postnatal changes of skeletal muscle protein fractional synthesis rates (FSR) and their correlations with serum concentrations of hormones (insulin, growth hormone and corti...

The Na+-neutral amino acid (AA) transporter B0 functions for the uptake of luminal neutral AA across the gut apical membrane. The aim of this study was to quantify B0 mRNA expression along the jeju...