Hypoxic induction of interleukin-8 gene expression in human endothelial cells.

This is the published version. Copyright 1994 American Society for Clinical Investigation.Because leukocyte-mediated tissue damage is an important component of the pathologic picture in ischemia/reperfusion, we have sought mechanisms by which PMNs are directed into hypoxic tissue. Incubation of human endothelial cells (ECs) in hypoxia, PO2 approximately 14-18 Torr, led to time-dependent release of IL-8 antigen into the conditioned medium; this was accompanied by increased chemotactic activity for PMNs, blocked by antibody to IL-8. Production of IL-8 by hypoxic ECs occurred concomitantly with both increased levels of IL-8 mRNA, based on polymerase chain reaction analysis, and increased IL-8 transcription, based on nuclear run-on assays. Northern analysis of mRNA from hypoxic ECs also demonstrated increased levels of mRNA for macrophage chemotactic protein-1, another member of the chemokine superfamily of proinflammatory cytokines. IL-8 gene induction was associated with the presence of increased binding activity in nuclear extracts from hypoxic ECs for the NF-kB site. Studies with human umbilical vein segments exposed to hypoxia also demonstrated increased elaboration of IL-8 antigen compared with normoxic controls. In mice exposed to hypoxia (PO2 approximately 30-40 Torr), there was increased pulmonary leukostasis, as evidenced by increased myeloperoxidase activity in tissue homogenates. In parallel, increased levels of transcripts for IP-10, a murine homologue in the chemokine family related to IL-8, were observed in hypoxic lung tissue. Taken together, these data suggest that hypoxia constitutes a stimulus for leukocyte chemotaxis and tissue leukostasis

Characteristics of gate-all-around silicon nanowire field effect transistors with asymmetric channel width and source/drain doping concentration

We performed 3D simulations to demonstrate structural effects in sub-20 nm gate-all-around silicon nanowire field effect transistors having asymmetric channel width along the channel direction. We analyzed the differences in the electrical and physical properties for various slopes of the channel width in asymmetric silicon nanowire field effect transistors (SNWFETs) and compared them to symmetrical SNWFETs with uniform channel width. In the same manner, the effects of the individual doping concentration at the source and drain also have been investigated. For various structural conditions, the current and switching characteristics are seriously affected. The differences attributed to the doping levels and geometric conditions are due to the electric field and electron density profile. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4745858]ope

The impact of age on post-operative outcomes of colorectal cancer patients undergoing surgical treatment

BACKGROUND: the purpose of study was to evaluate the impact of age on outcomes in colorectal cancer surgery. METHODS: patients on hospital database treated for colorectal cancer during the period 1995 – 2002 were divided into two groups: Group 1 – patients of 75 years or older (n = 154), and Group 2 – those younger than 75 years (n = 532). RESULTS: In Group 1, for colon cancers, proximal tumors were significantly more common (23% vs. 13.5%, p < 0.05), complicated cases were more frequent (46 % vs. 33%, p = 0.002), bowel obstruction more common at presentation (40% vs. 26.5%, p = 0.001), and more frequent emergency surgery required (24% vs. 14%, p = 0.003). Postoperative overall morbidity was higher in the elderly group, but with no differences in surgical complications rate. Overall 5 year survival was 39% vs. 55% (p = 0.0006) and cancer related 5 year survival was 44% vs. 62% (p = 0.0006). Multivariate Cox analysis showed that age was not an independent risk factor for postoperative mortality. CONCLUSION: Preoperative complications and co-morbidities, more advanced disease, and higher postoperative nonsurgical complication rates adversely affect postoperative outcomes after surgery for colorectal cancer in the elderly