BACKGROUND: CRC is one of the most common cancers in the world. K-ras is proto-oncogene with GTPase activity that is lost when the gene is mutated. Analysis of K-ras mutational status is very important for CRC treatment, being the most important predictors of resistance to targeted therapy. OBJECTIVE: This study aims to determine the frequency and spectrum of K-ras mutation among Iraqi patients with sporadic CRC. PATIENTS, MATERIALS AND METHODS: This study enrolled 35 cases with sporadic CRC; their clinicopathological parameters were analyzed. The FFPE blocks were used for DNA extraction; PCR amplification of K-ras gene and hybridization of allele-specific oligoprobes were performed. The assay covers 29 mutations in the K-ras gene (codons 12, 13, 59, 60, 61, 117 and 146). RESULTS: The majority of cases have left colonic tumours (57%), without LN involvement (57.1%), of non-mucinous adenocarcinoma histology (85.7%), grade II (82.9%) and stage III (37.1%) tumours. Fourteen mutations were detected in 13 (37%) patients with K-ras mutations; 10 (71.4%) mutations were in codon 12 while 4(28.6%) were in codon 13. The most frequent mutation was the G>T transversions [9 (64.4%)] and the most frequent mutation type was GGT>TGT (GLY>CYS) at codon 12. CONCLUSION: The incidence of K-ras mutations lies in the middle of the reported figures worldwide; the majority of mutations occurred at codon 12 followed by codon 13; predominantly of G>T transversion and Gly12Cys type that has a poorer prognosis.
Two simple methods for the determination of eugenol were developed. The first depends on the oxidative coupling of eugenol with p-amino-N,N-dimethylaniline (PADA) in the presence of K3[Fe(CN)6]. A linear regression calibration plot for eugenol was constructed at 600 nm, within a concentration range of 0.25-2.50 μg.mL–1 and a correlation coefficient (r) value of 0.9988. The limits of detection (LOD) and quantitation (LOQ) were 0.086 and 0.284 μg.mL–1, respectively. The second method is based on the dispersive liquid-liquid microextraction of the derivatized oxidative coupling product of eugenol with PADA. Under the optimized extraction procedure, the extracted colored product was determined spectrophotometrically at 618 nm. A l
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