29 research outputs found
Mathematical Description of the Change in Properties of Casuarina Wood Upon Exposure to Gamma Radiation. 1. Changes in the Compressive and Tensile Strength
Casuarina cunninghamiana specimens were exposed to gamma-radiation doses ranging from 104 to 108 rad and tested in compression and tension parallel to grain. The percentage values of the irradiated specimens relative to that of the matched control (Y) were determined. The relationship between (Y) and log gamma radiation dose (X) was represented mathematically by the equation: Y = aXbcx. This equation described the change in compressive and tensile strength very well as was detected from the high correlation coefficients. Generally these properties increased slightly at low levels of radiation, reached a maximum, then decreased gradually thereafter. The reduction in tensile strength was more pronounced than in compressive strength.The threshold dose, i.e., the dose beyond which the properties began to decrease, was calculated. This dose ranged from 3.69 x 106 to 3.76 x 106 rad for compressive strength properties and from 1.51 x 106 to 1.70 x 106 rad for tensile strength properties. This indicated that irradiated casuarina wood had a greater resistance to compression than to tension
The prognostic significance of wild type isocitrate dehydrogenase 2 (IDH2) in breast cancer
Background: Lymphovascular invasion (LVI) is a prerequisite step in breast cancer (BC) metastasis. We have previously identified wild type isocitrate dehydrogenase 2 (IDH2) as a key putative driver of LVI. Thus, we explored the prognostic significance of IDH2 at transcriptome and protein expression levels in pre-invasive and invasive disease.Methods: Utlising, tissue microarrays from a large well annotated BC cohort including ductal carcinoma in situ and invasive breast cancer (IBC), IDH2 was assessed at the transcriptomic and proteomic level. The associations between clinicopathological factors including LVI status, prognosis and the expression of IDH2 were evaluated.Results: In pure DCIS and IBC, high IDH2 protein expression was associated with features of aggressiveness including high nuclear grade, larger size, comedo-necrosis and hormonal receptor negativity and LVI, higher grade, larger tumour size, high NPI, HER2 positivity, and hormonal receptor negativity, respectively. High expression of IDH2 either in mRNA or protein levels was associated with poor patient’s outcome in both DCIS and IBC. Multivariate analysis revealed that IDH2 protein expression was an independent risk factor for shorter BC specific-survival.Conclusion: Further functional studies to decipher the role of IDH2 and its mechanism of action as a driver of BC progression and LVI are warranted
Effect of gamma irradiation on the properties of natural rubber/styrene butadiene rubber blends
Blends of natural rubber (NR) with styrene butadiene rubber (SBR) with varying ratios have been prepared. Vulcanization of the prepared blends has been induced by irradiation of gamma rays with varying doses up to 250 kGy. Mechanical properties, namely tensile strength, tensile modulus at 100% elongation, elongation at break have been followed up as a function of irradiation dose as well as blend composition. Physical properties, namely gel fraction and swelling number have been followed up using benzene as a solvent. Thermal measurements namely thermogravimetric analysis were carried out. The results indicated that the addition of NR has improved the properties of NR / SBR blends. Also NR/SBR blend is thermally stable than NR alone
Molecular Cloning And Sequencing Of Disintegrin Like Domain From Cerastes Cerastes Venom Gland
Disintegrin-like domain was cloned and sequenced from Cerastes cerastes venom gland tissue. Nested RT-PCR was performed using initial primers designed based on the homology of disintegrins from Trimeresurus flavoviridis, Glodius halys , Agkistrodon halys and Trimeresurus macrosquamatus. The homology was reached using BLAST searching tool. The primers were selected using doprimers algorithm. Nested primers were those reported by Yamada et al.,(1999) for Trimeresurus flavoviridis.
The nested PCR product was approximately 150 bP as determined by agarose gel electrophoresis. Cloning of the PCR product was performed using Qiagen PCR cloning system. The construct in pDrive cloning vector was introduced into competent JM109 bacterial cells (Promega). Plasmid DNA minipreps were prepared having the 150bp insert.
Sequence analysis of the insert gave 124 bp which is in extensive sequence homology with many snake venoms disintegrin domain.
Translation of the nucleotides sequence and searching the protein database revealed amino acid sequence of disintegrin with 70% consensus identity. Prosite motif search gave two phosphorylation sites (kinase c and casein kinase 1 ) . One myristoylation site was also identified. Four cysteines seems to form disulfide bonds.
Egyptian Journal of Biochemistry and Molecular Biology Vol. 25 (2) 2007: pp. 180-19
Rational Design and Synthesis of New Selective COX-2 Inhibitors with In Vivo PGE2-Lowering Activity by Tethering Benzenesulfonamide and 1,2,3-Triazole Pharmacophores to Some NSAIDs
New selective COX-2 inhibitors were designed and synthesized by tethering 1,2,3-triazole and benzenesulfonamide pharmacophores to some NSAIDs. Compounds 6b and 6j showed higher in vitro COX-2 selectivity and inhibitory activity (IC50 = 0.04 µM and S.I. = 329 and 312, respectively) than celecoxib (IC50 = 0.05 µM and S.I. = 294). Compound 6e revealed equipotent in vitro COX-2 inhibitory activity to celecoxib. Furthermore, 6b and 6j expressed more potent relief of carrageenan-induced paw edema thickness in mice than celecoxib, with ED50 values of 11.74 µmol/kg and 13.38 µmol/kg vs. 16.24 µmol/kg, respectively. Compounds 6b and 6j inhibited the production of PGE2 with a % inhibition of PGE2 production of 90.70% and 86.34%, respectively, exceeding celecoxib’s percentage (78.62%). Moreover, 6b and 6j demonstrated a gastric safety profile comparable to celecoxib. In conclusion, compounds 6b and 6j better achieved the target goal as more potent and selective COX-2 inhibitors than celecoxib in vitro and in vivo
Imparting aromaticity to 2-pyridone derivatives by O-alkylation resulted in new competitive and non-competitive PIM-1 kinase inhibitors with caspase-activated apoptosis
AbstractNew aromatic O-alkyl pyridine derivatives were designed and synthesised as Proviral Integration Moloney (PIM)-1 kinase inhibitors. 4c and 4f showed potent in vitro anticancer activity against NFS-60, HepG-2, PC-3, and Caco-2 cell lines and low toxicity against normal human lung fibroblast Wi-38 cell line. Moreover, 4c and 4f induced apoptosis in the four tested cancer cell lines with high percentage. In addition, 4c and 4f significantly induced caspase 3/7 activation in HepG-2 cell line. Furthermore, 4c and 4f showed potent PIM-1 kinase inhibitory activity with IC50 = 0.110, 0.095 µM, respectively. Kinetic studies indicated that 4c and 4f were both competitive and non-competitive inhibitors for PIM-1 kinase enzyme. In addition, in silico prediction of physiochemical properties, pharmacokinetic profile, ligand efficiency, ligand lipophilic efficiency, and induced fit docking studies were consistent with the biological and kinetic studies, and predicted that 4c and 4f could act as PIM-1 kinase competitive non-adenosine triphosphate (ATP) mimetics with drug like properties