Phenylglyoxal, a chemical modifying agent for arginine residues, produced rapid inactivation of a rat liver phenol sulfotransferase (3-phosphoadenylylsulfate:phenol sulfotransferase, EC 2.8.2.1). Enzyme inactivation was accompanied by incorporation of 1.5 mol [7−14C]phenylglyoxal per mol enzyme....

Periodate oxidation of eight N6-substituted adenosine derivatives was performed with the aim of oxidizing the vicinal 2′ and 3′ hydroxyl groups of the ribose moiety. A thermodynamical and pharmacological characterization of the products of this transformation allowed us to verify that oxidized...

Endogenous adenosine in the extracellular space inhibits neuronal activity. The roles of adenosine kinase, S-adenosylhomocysteine-hydrolase and adenosine deaminase activities in the regulation of the adenosine levels were investigated in rat hippocampal slices. Iodotubercidin, an inhibitor of ad...

The S-adenosylhomocysteine (SAH) hydrolase inhibitor adenosine dialdehyde was used in isolated guinea pig hearts to determine the contribution of the transmethylation pathway to cardiac adenosine formation. This inhibitor did not alter cardiac hemodynamics but effectively inhibited SAH-hydrolase...

A highly sensitive capillary electrophoresis method has been developed to monitor the activity of nucleotide pyrophosphatases/phosphodiesterases (NPPs) and screen for NPP inhibitors. In this method, p-nitrophenyl 5′-thymidine monophosphate (p-Nph-5′-TMP) was used as an artificial substrate, an...

Purine nucleotide synthesis in protozoa takes place exclusively via the purine salvage pathway and S-adenosyl-l-homocysteine hydrolase (SAHH) is an important enzyme in the Plasmodium salvage pathway which is not present in erythrocytes. Here, we describe the antimalarial effect of 2′3′-dialdeh...

BackgroundIdentification of patients with thiopurine S-methyltransferase (TPMT) deficiency prior to thiopurine drug therapy has become routine clinical practice worldwide. To measure TPMT activity, traditional radiochemical assays have been replaced by chromatographic methods.

The thermal decomposition of nonadeuterio trimethylsulfoxonium iodide, prepared from the nondeuterated salt and deuterium oxide, gives a high yield of methyl-d3 iodide. Direct alkylation of the l-homocysteine anion, generated by the sodium-liquid ammonia reduction of l-methionine by methyl-d3iod...

The microorganisms Scopulariopsis brevicaulis, Candida humicola, and Gliocladium roseum growing aerobically, methylate a range of arsenic compounds to produce R′R″As(CH3) (R′  R″  CH3; R′  n-C4H9, R″  CH3). When l-methionine-methyl-d3 is added to the cultures the CD3 label is incor...

Polyphysa peniculus growing in artificial seawater methylates arsenate to produce a dimethylarsenic derivative, probably dimethylarsinate. When L-methionine-methyl-d3 is added to the culture the CD3 label is incorporated intact in the dimethylarsenic compound to a considerable extent, indicating...

SummaryBackgroundTreatment options for recurrent glioblastoma are scarce, with second-line chemotherapy showing only modest activity against the tumour. Despite the absence of well controlled trials, bevacizumab is widely used in the treatment of recurrent glioblastoma. Nonetheless, whether the ...

A simple, inexpensive and rapid liquid chromatography (LC) method has been developed for the quantitative determination of Lomustine, an chemotherapy drug. Degradation studies were performed on the bulk drug by heating to 60 °C, exposure to UV light at an energy of 200 Wh/m2and to visible light...

SummaryBackgroundThere is an urgent need for more effective therapies for glioblastoma. Data from a previous unrandomised phase 2 trial suggested that lomustine-temozolomide plus radiotherapy might be superior to temozolomide chemoradiotherapy in newly diagnosed glioblastoma with methylation of ...

Mast cell tumours (MCTs) in dogs can present in a variety of forms. Non-resectable, recurrent or metastatic MCTs usually carry a poor prognosis and present a therapeutic challenge. Both toceranib and lomustine have shown single agent activity against MCTs in dogs. In this study, 10 dogs with adv...

Investigation of drug–DNA interaction is important for understanding the drug action at molecular level and for designing specific DNA targeted drug. Lomustine (CCNU = 1-[2-chloroethyl]-3-cyclohexyl-1-nitroso-urea) is an alkylating antineoplastic nitrosourea derivative, used to treat different ...

SummaryBackgroundGlioblastoma is a highly vascularised tumour and there are few treatment options after disease recurrence. Regorafenib is an oral multikinase inhibitor of angiogenic, stromal, and oncogenic receptor tyrosine kinases. We aimed to assess the efficacy and safety of regorafenib in t...

Lomustine is a nitrosourea used for the treatment of cancer. An alkylating agent, lomustine differs from other members of this class in being relatively lipid soluble and therefore capable of crossing the blood-brain barrier. For this reason, lomustine is employed for the treatment of tumors loc...

Electrochemical techniques were used to investigate the behavior of lomustine (CCNU) and its degradation in aqueous solution at a glassy carbon electrode (GCE). The in situ interaction of CCNU and chemically degraded CCNU (cdCCNU) with dsDNA was then investigated in dsDNA incubated solutions, us...

Cadmium has been shown to cause significant inhibition of lymphocyte metabolism, including DNA synthesis, in both in vitro and in vivo studies. In order to understand more clearly the modification of DNA synthesis, this study has examined the metabolism of radiolabelled thymidine in splenocytes ...

Bile acids have been reported to modify DNA synthesis by rodent livers in regeneration, which may be due in part to their ability to interact with the machinery responsible for deoxyribonucleotide synthesis. The aim of this work was to gain information on the effect of taurocholate (TC) on both ...