4-Allyl-4-hydroperoxy-2-methoxycyclohexa-2,5-dienone (5) was synthesized by photooxygenation of commercially available Eugenol in the presence of tetraphenylporphyrin (TPP) as a singlet oxygen sensitizer. The brief and one-pot syntheses of some natural product skeletons were conducted using the corresponding allylic hydroperoxide at different temperatures (0 o C and room temperature) with potas...

A simple and convenient method for the construction of CdSe/ZnS-labeled polysaccharides as bioprobes were developed, which are highly biocompatible and photostable, and have been proven to be suitable for live cell imaging.

A plasmid encoding a recombinant human O6-methylguanine-DNA methyltransferase (MGMT) fused to a fragment of the bacteriophage lambda N protein has been constructed. The fusion protein retained methyltransferase activity when expressed at high levels in E.coli and was purified to essential homogeneity by a simple procedure. Antisera raised against the purified fusion protein recognized MGMT in w...

A synthetic oligonucleotide containing ribozyme sequences targeted to the 5' region of the human O6-methylguanine-DNA methyltransferase (MGMT) mRNA has been constructed. This ribozyme demonstrates cleavage activity in vitro in the presence of Mg2+. To determine whether this ribozyme can function in vivo, HeLa CCL2 cells were transfected with a mammalian expression vector containing the ribozyme...

O(6)-methylguanine-DNA methyltransferase plays vital roles in preventing induction of mutations and cancer as well as cell death related to alkylating agents. Mice defective in the MGMT: gene, encoding the methyltransferase, were used to evaluate cell death-inducing and tumorigenic activities of therapeutic agents which have alkylation potential. MGMT(-/-) mice were considerably more sensitive ...

Catechol O-methyltransferase (COMT) metabolizes catechol moieties by methylating a single hydroxyl group at the meta- or para- hydroxyl position. Hydrophobic amino acids near the active site of COMT influence the regioselectivity of this reaction. Our sequence analysis highlights their importance by showing that these residues are highly conserved throughout evolution. Reaction barriers calcula...

It has previously been shown that incubation of mammalian cell cytosolic extracts with the protein kinase inhibitor tyrphostin A25 results in enhanced transfer of methyl groups from S-adenosyl-[methyl-3H]methionine to proteins. These findings were interpreted as demonstrating tyrphostin stimulation of a novel type of protein carboxyl methyltransferase. We find here, however, that tyrphostin A25...

Aim. Acute pancreatitis is an inflammatory intra-abdominal disease, which takes a severe form in 15-20% of patients and can result in high mortality especially when complicated by acute renal failure. The aim of this study is to assess the possible reduction in the extent of acute kidney injury after administration of eugenol in an experimental model of acute pancreatitis. Materials and Methods...