Development of a risk assessment model for Oman construction industry

Oman as one of the Arabian Gulf countries which have invested billions of dollars in the construction industries, infrastructural services and real estate, but it is clearly identified that risk assessment was not applied for once on these awarded contracts. Lack of knowledge and awareness of risk management or assessment procedures in the construction industry in Oman caused additional cost and time delay in most of the awarded construction projects. This paper aimed at developing a model for risk assessment in the Oman construction industry to save huge amounts of millions of money wasted due to this problem. A field survey of semi-structured questionnaire with face-to-face interviews was carried out in the Oman construction industry including public, contractors and consultants. The research approach relies on data collected from primary and secondary sources. Combination of quantitative and qualitative data analysis was used in analysing the data for the Model development. The risk factors in the Oman construction industry varies from one category to another, the risk factors in government category are more than the consultant category and contractor’s category. Overall, the Oman construction industry has no very high risk factors, which means it has good opportunities for investment. It is expected that the output of this research will have a good and beneficial contribution to save time and money for both public and private sectors in Oman due to expected awareness and improvements in the risk assessment procedure

Perturbation of Mouse Retinal Vascular Morphogenesis by Anthrax Lethal Toxin

Lethal factor, the enzymatic moiety of anthrax lethal toxin (LeTx) is a protease that inactivates mitogen activated protein kinase kinases (MEK or MKK). In vitro and in vivo studies demonstrate LeTx targets endothelial cells. However, the effects of LeTx on endothelial cells are incompletely characterized. To gain insight into this process we used a developmental model of vascularization in the murine retina. We hypothesized that application of LeTx would disrupt normal retinal vascularization, specifically during the angiogenic phase of vascular development. By immunoblotting and immunofluorescence microscopy we observed that MAPK activation occurs in a spatially and temporally regulated manner during retinal vascular development. Intravitreal administration of LeTx caused an early delay (4 d post injection) in retinal vascular development that was marked by reduced penetration of vessels into distal regions of the retina as well as failure of sprouting vessels to form the deep and intermediate plexuses within the inner retina. In contrast, later stages (8 d post injection) were characterized by the formation of abnormal vascular tufts that co-stained with phosphorylated MAPK in the outer retinal region. We also observed a significant increase in the levels of secreted VEGF in the vitreous 4 d and 8 d after LeTx injection. In contrast, the levels of over 50 cytokines other cytokines, including bFGF, EGF, MCP-1, and MMP-9, remained unchanged. Finally, co-injection of VEGF-neutralizing antibodies significantly decreased LeTx-induced neovascular growth. Our studies not only reveal that MAPK signaling plays a key role in retinal angiogenesis but also that perturbation of MAPK signaling by LeTx can profoundly alter vascular morphogenesis

Management of Neovascular AMD

VEGF is the most important regulator of angiogenesis and a potent promoter of vascular permeability in different ocular diseases, including AMD. For this reason, VEGF is a key target in treating ocular neovasculari-zation. Two anti-VEGF agents have achieved regulatory approval, with others in clinical trials. Clinical trials have shown that intravitreal ranibizumab is safe drug and effective, being the first agent to promote visual acuity improvement in patients with wet AMD. Bevacizumab, a monoclonal antibody against VEGF, was approved for intravenous, systemic therapy for different types of cancer. It has been used off-label as an intravitreal injection in wet AMD since 2005 with clinical results similar to ranibizumab. CATT head-to-head trial comparing bevacizumab versus ranibizumab demonstrated that they have similar outcomes when the same treatment regimen is applied. New promising anti-VEGF drugs (VEGF-Trap, KH902, and Pazopanib) are in ongoing clinical trials