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Integrin α9β1 mediates accelerated cell adhesion and migration through interactions with a number of diverse extracellular ligands. We have shown previously that it directly binds the vascular endothelial growth factors (VEGF) A, C, and D and contributes to VEGF-induced angiogenesis and lymphangiogenesis. Until now, the α9β1 binding site in VEGF has not been identified. Here, we report that the three-amino acid sequence, EYP, encoded by exon 3 of VEGF-A is essential for binding of VEGF to integrin α9β1 and induces adhesion and migration of endothelial and cancer cells. EYP is specific for α9β1 binding and neither requires nor activates VEGFR-2, the cognate receptor for VEGF-A. Following binding to EYP, integrin α9β1 transduces cell migration through direct activation of the integrin signaling intermediates Src and focal adhesion kinase. This interaction is biologically important because it mediates in vitro endothelial cell tube formation, wound healing, and cancer cell invasion. These novel findings identify EYP as a potential site for directed pharmacotherapy. [ABSTRACT FROM AUTHOR]

Seeds of Artemisia annua cv. Jeevanraksha were sown in the nursery in the middle of December in 1997, 1998 and 1999. About 1-month old seedlings were transplanted in the field having sandy loam soil in the subtropical agroclimate of Lucknow, India. The plant tops were sampled fortnightly for leaves during vegetative phase and for leaves and capitula during post-flowering stages for the estimation of artemisinin content. The A. annua plants continued to grow logarithmically in height from the end of rosette phase at about 9 weeks to the pre-flowering stage at about 44 weeks age and attained a height of 3.4 m. The artemisinin content of the leaves was observed to be high from 0.8 to 1.0% in May and 0.8 to 1.3% through late July to late September. Subsequently, plants entered the reproductive phase. While in the vegetative phase, 90% of artemisinin was in the leaves, in the mature plants, about 30% of the artemisinin was in the leaves and 40% was in capitula. In the vegetative stage plants the younger leaves born on the tops of secondary and higher order branches were richer in the artemisinin than the older leaves. The tops of A. annua plants in their vegetative growth phase possessed low levels of essential oil at about 0.2% as compared to 1.2% of essential oil in the full blooming stage plants. The extraction of artemisinin from leaves is more economic than from the mixture of leaves and capitula on account of higher levels of lipids in the extract of the latter. Since A. annua plants grew logarithmically all through vegetative phase from March to late September and artemisinin content in the leaves was high in May and from late July to late September, it is suggested that under the subtropical agroclimates, A. annua crops may be harvested more than once. The ratooning is expected to reduce losses in artemisinin yield resulting from senescence caused dropping of old leaves and favour preponderance of young leaves found richer in artemisinin content. [Copyright &y& Elsevier]

We report an improved H 2 S response of flexible gold (Au)–cobalt phthalocyanine (CoPc) heterojunction thin films at room temperature. The Au–CoPc films exhibit very high charge carrier density at the surface due to (i) the difference in work function of Au and CoPc and (ii) enhanced adsorbed oxygen on the CoPc surface owing to spillover effect. Both of these effects make the Au–CoPc films more oxidative to the H 2 S in comparison to pure CoPc films. The response of the films on exposure to H 2 S is attributed to the shrinkage of the hole accumulation layer of CoPc due to electron transfer from adsorbed electron donor H 2 S. The gas sensing characteristics of the films were found to be stable for the bending radius >20 mm. [ABSTRACT FROM AUTHOR]

Highlights: [•] Flexible PANI–Ag nanocomposites films were synthesized on APTMS modified BOPET. [•] PANI–Ag films exhibit highly selective/sensitive detection of H2S at ppm level. [•] The films prepared on modified BOPET shows enhanced response in comparison to that on pristine one. [ABSTRACT FROM AUTHOR]

TGF-β modulates numerous diverse cellular phenotypes including growth arrest in epithelial cells and proliferation in fibroblasts, Although the Smad pathway is fundamental for the majority of these responses, recent evidence indicates that non-Smad pathways may also have a critical role. Here we report a novel mechanism whereby the nonreceptor tyrosine focal adhesion kinase (FAK) functions as an adaptor necessary for cell type-specific responses to TGF-β. We show that in contrast to Smad actions, non-Smad pathways, including c-Abl, PAK2, and Akt, display an obligate requirement for FAK. Interestingly, this occurs in Src null SYF cells and is independent of FAK tyrosine phosphorylation, kinase activity, and/or proline-rich sequences in the C-terminal FAT domain. FAK binds the phosphatidylinositol 3-kinase (PI3K) p85 regulatory subunit following TGF-β treatment in a subset of fibroblasts but not epithelial cells and has an obligate role in TGF-β-stimulated anchorage-independent growth and migration. Together, these results uncover a new scaffolding role for FAK as the most upstream component regulating the profibrogenic action of TGF-β and suggest that inhibiting this interaction may be useful in treating a number of fibrotic diseases. [ABSTRACT FROM AUTHOR]