Nature meets nurture: molecular genetics of gastric cancer

The immensity of genes and molecules implicated in gastric carcinogenesis is overwhelming and the relevant importance of some of these molecules is too often unclear. This review serves to bring us up-to-date with the latest findings as well as to look at the larger picture in terms of how to tackle the problem of solving this multi-piece puzzle. In this review, the environmental nurturing of intestinal cancer is discussed, beginning with epidemiology (known causative factors for inducing molecular change), an update of H. pylori research, including the role of inflammation and stem cells in premalignant lesions. The role of E-cadherin in the nature (genotype) of diffuse gastric cancer is highlighted, and finally the ever growing discipline of SNP analysis (including IL1B) is discussed

Indentation fracture toughness and surface flaw analysis of sintered alumina/SiC nanocomposites

The fracture toughness (K1c) of pressureless-sintered monolithic α-alumina and its composites with 5, 10 and 15 vol% SiC nano-sized particles was investigated using Vickers indentation and a new Hertzian (ball) indentation technique. Both methods showed that the fracture toughness of the composites is better than that of alumina, although the results from the Vickers indentations were complicated by a change in crack geometry from median/radial (alumina) to Palmqvist (composites) An analysis of the number and size of surface flaws using the Hertzian test indicates that, for the same polishing treatment, the composites have a better surface finish. © 1996 Elsevier Science Limited

CSF biomarkers of monocyte activation and chemotaxis correlate with magnetic resonance spectroscopy metabolites during chronic HIV disease

BACKGROUND: HIV-associated neurocognitive disorders (HAND) persist despite combination antiretroviral therapy (cART), supporting the need to better understand HIV neuropathogenesis. Magnetic resonance spectroscopy (MRS) of the brain has demonstrated abnormalities in HIV-infected individuals despite cART. We examined the associations between MRS metabolites and selected cerebrospinal fluid (CSF) biomarkers reflecting monocyte/macrophage activation and chemotaxis. METHODS: A multicenter cross-sectional study involving five sites in the United States was conducted. The following CSF biomarkers were measured: soluble CD14 (sCD14), monocyte chemotactic protein 1 (MCP-1), interferon inducible protein 10 (IP-10), and stromal cell derived growth factor 1 alpha (SDF-1α). The following MRS metabolites were measured from basal ganglia (BG), frontal white matter (FWM) and frontal gray matter (FGM): N-acetyl-aspartate (NAA), Myo-inositol (MI), Choline (Cho), and Creatine (Cr). CSF biomarkers were compared to absolute MRS metabolites as well as metabolite/Cr ratios using linear regression. RESULTS: 83 HIV-infected individuals were included, 78% on cART and 37% with HAND. The most robust positive correlations were between MCP-1 and Cho in BG (R(2) 0.179, p<0.001) as well as MCP-1 and MI in FWM (R(2) 0.137, p=0.002). Higher Cr levels in FWM were associated with MCP-1 (R(2) 0. 075, p=0.01) and IP-10 (R(2) 0.106, p=0.003). Comparing biomarkers to MRS metabolite/Cr ratios impacted some relationships, e.g., higher sCD14 levels were associated with lower Cho/Cr ratios in FGM (R(2) 0.224, p<0.001), although higher MCP-1 levels remained associated with Cho/Cr in BG. CONCLUSION: These findings provide evidence that monocyte activation and chemotaxis continue to contribute to HIV-associated brain abnormalities in cART-treated individuals