Discovery of anti-cell migration activity of an anti-HIV heterocyclic compound by identification of its binding protein hnRNP M.

One compound sometimes shows two biological functions, becoming important aspect of recent drug discovery. This study began with an attempt to confirm the previously reported molecular mechanism of the anti-human immunodeficiency virus (HIV) heterocyclic compound BMMP [2-(benzothiazol-2-ylmethylthio)-4-methylpyrimidine], i.e., induction of abnormal uncoating of the viral core at the post-entry step. Our mechanistic study gave results consistent with this mechanism. We further attempted to find out the molecular target of BMMP by a pulldown approach using previously synthesized biotinylated BMMP (Biotin-BMMP) and successfully identified heterogenous nuclear ribonucleoprotein M (hnRNP M) as a BMMP-binding protein. This protein was found not to be accountable for the anti-HIV activity of BMMP. As hnRNP M has been reported to promote cancer metastasis, we tested this mechanism and found that BMMP suppressed migration of the human lung carcinoma cell line A549 stimulated with transforming growth factor-ß (TGF-ß). Mechanistic study showed that BMMP suppressed the expression of CD44 mRNA via the regulation of hnRNP M. Furthermore, six new derivatives of BMMP were synthesized, and the patterns of their activities against HIV-1 and cell migration were not uniform, suggesting that the anti-HIV mechanism and the anti-cell migration mechanism of BMMP are independent. Taken together, the anti-cell migration activity of the anti-HIV heterocyclic compound BMMP was newly discovered by identification of its binding protein hnRNP M using a chemical biology approach.

Surface Plasmon Resonance-Based Membrane Protein-Targeted Active Ingredients Recognition Strategy: Construction and Implementation in Ligand Screening from Herbal Medicines.

Membrane proteins (MPs) are playing important roles in several biological processes. Screening new candidate compounds targeting MPs is important for drug discovery. However, it remains challenging to characterize the interactions between MPs and small-molecule ligands in a label-free method. In this study, a surface plasmon resonance (SPR)-based membrane protein-targeted active ingredients recognition strategy was constructed. This strategy contains two major modules: affinity detection module and ligand screening module. Through the combination of these two functional modules, it is feasible to screen small molecular ligands targeting MPs from herbal medicines. First, we have constructed high/low comparative C-X-C chemokine receptor type 4 (CXCR4)-expressed lentiviral particles (LVPs) models and characterized the expression levels. Then we immobilized LVPs on CM5 chips and detected the affinity between AMD3100 and CXCR4 by using affinity detection module. The KD of AMD3100 was 32.48 ± 3.17 nM. Furthermore, the suitability and robustness of the ligand screening module were validated by using AMD3100 as a positive compound. Subsequently, this module was applied in the screening of CXCR4 small molecular ligands from herbal medicine extracts. Senkyunolide I was screened out from Chuanxiong extract. The affinity constant between senkyunolide I and CXCR4 was 2.94 ± 0.36 µM. The Boyden chamber assay revealed that senkyunolide I could inhibit cell migration process. In conclusion, an SPR-based small molecular ligand recognition strategy combined with virus-based membrane protein stabilization method was constructed. The SPR-based membrane protein-targeted active ingredients recognition strategy will be an effective tool to screen target components from complex systems acting on MPs.

Inhibition of 2-Amino-1-methyl-6-phenylimidazo [4,5-b]pyridine (PhIP) Formation by Alkoxy Radical Scavenging of Flavonoids and Their Quantitative Structure-Activity Relationship in a Model System.

The inhibitory effect of 10 flavonoids on the formation of 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) in a creatinine-phenylalanine model system was investigated through electronic spin resonance and a quantitative structure-activity relationship. Alkoxy radicals were observed during the heating process, providing evidence for a radical pathway in the formation of PhIP. The alkoxy radical scavenging capability of the flavonoids was proportional to their inhibition of PhIP formation (IC50 ). We deduced that flavonoid inhibition of PhIP generation occurs via scavenging of alkoxy radicals during the heating process. Multiple linear regression and partial least squares models were used to elucidate the relationship between PhIP inhibition activity and structure characteristics of the flavonoids. The lipo-hydro partition coefficient and molecular fractional polar surface area of the flavonoids were found to be predictive of the inhibition effect.

Isolation and classification of a soil actinomycete capable of sulphur-specific biotransformation of dibenzothiophene, benzothiophene and thianthrene.

AIM: To isolate actinomycete spp with the ability to desulphurize sulphur-containing heterocyclic compounds present in petroleum. METHODS AND RESULTS: Enrichment cultures were set up to select and isolate sulphur heterocycle metabolizing soil micro-organisms. Screening of the microbial isolates for the desulphurization property led to isolation of R3. The isolate was characterized by PCR screening of 16S rRNA genes and classical taxonomic investigations. HPLC analysis of the desulphurization assays with R3 showed ~85% transformation of dibenzothiophene (270 µmol l(-1)), present as the sole sulphur source in basal salt medium, in 4 days. Production of the desulphurized dibenzothiophene metabolite, 2-hydroxybiphenyl, was confirmed by GC/MS analyses. GC/MS analyses also established the ability of R3 to transform benzothiophene to benzothiophene-1-oxide and benzothiophene-1, 1-dioxide, and thianthrene to thianthrene-5-oxide. PCR primers computed based on the desulphurization operon (dszABC) of Rhodococcus erythropolis IGTS8 yielded the predicted amplification products with R3 genomic DNA as template. Southern hybridization and restriction endonuclease digestion profiles indicated that R3 amplicons were homologous to dsz AB. CONCLUSIONS: The enrichment method used in this study yielded an environmental isolate with the ability to transform multiple sulphur heterocycles. The isolate R3 has taxonomic proximity to the Oerskovia sp, order Actinomycetales. The isolate R3 selectively removes sulphur from dibenzothiophene yielding 2-hydroxybiphenyl and sulphate. R3 also transforms benzothiophene and thianthrene in a sulphur-targeted manner. The desulphurization genes in R3 bear similarity to those in R. erythropolis IGTS8. SIGNIFICANCE AND IMPACT OF THE STUDY: The actinomycetes present in soil can remove sulphur from different sulphur heterocycle substrates and have potential as biodesulphurization catalysts.

[Fish intake and risk of prostate cancer]. / Spozycie ryb a ryzyko wystapienia raka prostaty.

The aim of the study was to present the current state of knowledge concerning the relationship between the consumption of fish as materials rich in long chain polyunsaturated fatty acids (LC PUFA) omega-3, and the risk of prostate cancer. Many scientific reports confirm the health benefits from the consumption of fish and protective properties of LC PUFA omega-3 in relation to prostate cancer. However, there are reports that indicate a relationship of the high consumption of PUFA with the risk of prostate cancer. The way of processing and preservation of the fish, and other factors not included in previous studies, could have some importance in the etiology of this disease. High susceptibility of PUFA to oxidation changes and the technological fish processing (smoking, high-temperature cooking methods) contribute to the formation of many compounds, such as polycyclic aromatic hydrocarbons and heterocyclic amines - which may influence the formation of cancers - including prostate cancer. It is necessary to ensure an adequate amount of LC PUFA omega-3 in the diet through the consumption of proper quality fish and fish oils. Particular attention should be paid to the high susceptibility of PUFA to the oxidative processes, and the method of processing, preservation and storage of fish. Also pollution from the environment can significantly reduce the impact of health benefits of PUFA and fish, and even be the cause of cancers, including prostate cancer. Further research in this area should be more targeted to assess the impact of nutritional factors for the development of such tumors.

Concentration-dependent inhibition of Escherichia coli O157:H7 and heterocyclic amines in heated ground beef patties by apple and olive extracts, onion powder and clove bud oil.

The effects of plant compounds on Escherichia coli O157:H7 and two major heat-induced heterocyclic amines (HCAs) MeIQx and PhIP in grilled ground beef patties were determined. Ground beef with added apple and olive extracts, onion powder, and clove bud oil was inoculated with E. coli O157:H7 (107 CFU/g) and cooked to reach 45 °C at the geometric center, flipped and then cooked for another 5 min. Cooled samples were taken for microbiological and HCA analyses. Olive extract at 3% reduced E. coli O157:H7 to below detection. Reductions of up to 1 log were achieved with apple extract. Olive and apple extracts reduced MeIQx by up to 49.1 and 50.9% and PhIP by up to 50.6 and 65.2%, respectively. Onion powder reduced MeIQx and PhIP by 47 and 80.7%, respectively. Inactivation of E. coli O157:H7 and suppression of HCAs in grilled meat were achieved by optimized amounts of selected plant compounds.

Metal-free cleavage efficiency toward DNA by a novel PNA analog-bridged macrocyclic polyamine.

In this report we describe the synthesis of a new class of cyclen-contained compounds with novel peptide nucleic acid (PNA) analog motif. Target bis-cyclen derivative B was prepared and characterized by ESI-MS, NMR and HPLC. Interactions between compound B and calf thymus DNA were studied by thermal denaturation. Results indicate that the DNA binding affinity of B is stronger than that of mono-cyclen compound A, and the binding ability is little affected by the change of ionic strength. Agarose and denaturing polyacrylamide gel electrophoresis were used to assess the DNA cleavage activities. The macrocyclic polyamine-PNA analog conjugate B as a nuclease model can effectively cleave DNA via an oxidative pathway at micromolar concentration (10 µM) without the use of any additional metal ions. Meanwhile, the mono-cyclen compound A shows nearly no DNA cleavage effect under the same conditions.

Photochemistry of trans-Cr(cyclam)(ONO)2+, a nitric oxide precursor.

Experimental and density functional theory (DFT) studies are described that are focused on outlining the reactivity of the known photochemical nitric oxide precursor trans-Cr(cyclam)(ONO)(2)(+) ("CrONO", cyclam = 1,4,8,11-tetrazacycltetradecane). Studies in both aerated and deaerated aqueous media are described as are the roles of both the oxidant O(2) and a reductant such as glutathione in trapping the apparent Cr(IV) photoreaction intermediate trans-Cr(cyclam)(O)(ONO)(+). Also reported and characterized structurally is the Cr(V) product of long-term photolysis in the absence of reducing agents, the trans-dioxo species [trans-Cr(cyclam)(O)(2)](ClO(4)). Photosensitization experiments indicate that at least a significant fraction of the reaction occurs from the lowest energy doublet excited state(s). Lastly, cell culture experiments demonstrate that CrONO has little or no acute toxicity either before or after photolysis.

The effect of green tea and olive oil on the mutagenic activity of heterocyclic amines extracted from common food consumed in Saudi Arabia.

The effect of green tea (GT) and green tea with olive oil (GT+OL) as antioxidants on the formation and mutagenic activity of heterocyclic aromatic amines (HCAs) extracted from beef shawerma, grilled chicken and fried beef liver was examined. HCAs were extracted by blue rayon, analyzed as spiked and unspiked samples with high-performance liquid chromatography and its mutagenic response was assessed by Sallmonela typhimurium 100 in the Ames test. Surprisingly, GT and GT+OL augmented HCAs measured in beef shawerma and grilled chicken but total HCAs measured in GT+OL were less than GT treatment. Both treatments altered the HCA profile as imidazoquinoline type became the most abundant. In control and GT+OL fried beef liver no HCAs were detected, but Trp-P1 was detected in GT treatment. Generally, the mutagenic response of HCAs measured in GT+OL was less than GT in beef shawerma and grilled chicken. However, the mutagenic response of control and 2% GT+OL fried liver was negative. These data suggest that GT concentrations used in this study may induce free radical formation during the Millared reaction due to its pro-oxidative effect, which augmented the HCAs formed and its mutagenic response. In order to optimize both safety and quality of our diets, more need to be done to fully understand the risk of HCAs in food.

Biodegradation of the high explosive hexanitrohexaazaiso-wurtzitane (CL-20).

The aerobic biodegradability of the high explosive CL-20 by activated sludge and the white rot fungus Phanerochaete chrysosporium has been investigated. Although activated sludge is not effective in degrading CL-20 directly, it can mineralize the alkaline hydrolysis products. Phanerochaete chrysosporium degrades CL-20 in the presence of supplementary carbon and nitrogen sources. Biodegradation studies were conducted using various nutrient media under diverse conditions. Variables included the CL-20 concentration; levels of carbon (as glycerol) and ammonium sulfate and yeast extract as sources of nitrogen. Cultures that received CL-20 at the time of inoculation transformed CL-20 completely under all nutrient conditions studied. When CL-20 was added to pre-grown cultures, degradation was limited. The extent of mineralization was monitored by the (14)CO(2) time evolution; up to 51% mineralization was achieved when the fungus was incubated with [(14)C]-CL-20. The kinetics of CL-20 biodegradation by Phanerochaete chrysosporium follows the logistic kinetic growth model.

A new type of five-membered heterocyclic inhibitors of basic metallocarboxypeptidases.

A structure-based virtual screening survey was used to identify potential inhibitors of the human M14 family of metallocarboxypeptidases. A good correlation between docking energy scores and measured K(i) values was observed, indicating an efficient performance of the screening procedure. Among various compounds displaying K(i) values in the low micromolar range, N-(3-chlorophenyl)-4-((5-(3-methoxybenzylthio)-1,3,4-oxadiazol-2-yl)methyl)thiazol-2-amine emerged as the most powerful inhibitor for human carboxypeptidase B (CPB). According to molecular docking, this compound fits into CPB active site cleft through coordination of the catalytic zinc ion with the 1,3,4-oxadiazole moiety. This represents a novel five-membered heterocyclic type of inhibitor for disease-linked metallocarboxypeptidases and an interesting lead for further development.

Androgenic profile and genotoxicity evaluation of testosterone propionate and novel synthesized heterocyclic steroids.

In this study, we tested the androgenic activity of three structurally promising novel synthesized heterocyclic steroids compared with testosterone propionate in male mice. Additionally, the possible genotoxic effects of the novel synthesized heterocyclic steroids in comparison with testosterone propionate on male mice using chromosomal analysis of somatic and germ cells as well as RAPD-PCR were investigated. Male mice were administered with two doses of testosterone propionate, pyridoandrostene derivative 4b, pyrimidinoandrostene derivative 9a and thienoandrostene derivative 12 (200 and 400mg/kg b.w.) daily for 2 weeks. Results indicated that compounds 4b and 12 have androgenic activity as well as testosterone propionate. There were no significant differences in the frequencies of total chromosomal aberrations in both somatic and germ cells as well as no alteration in the DNA bands patterns between control, testosterone propionate and pyridoandrostene 4b treated animals. However, the pyrimidinoandrostene derivative 9a caused significant increase in the mean value of total chromosomal aberrations of both somatic and germ cells (P< or =0.01) as well as enhanced the polymorphic bands patterns as compared to the control and the other tested compounds. On the other hand, thienoandrostene derivative 12 induced significant decrease in the mean values of chromosomal aberrations in both somatic and germ cells, decreased sperm morphological abnormalities, increased the sperm count and motility than control. Our data indicate that testosterone propionate; pyridoandrostene 4b and thienoandrostene derivative 12 have no genotoxic activity. However, pyrimidinoandrostene derivative 9a has genotoxic activity possibly due to a modulation of the different expression of the catalyzing enzyme systems which will be investigated in the nearly future.

Biochemical interpretation of quantitative structure-activity relationships (QSAR) for biodegradation of N-heterocycles: a complementary approach to predict biodegradability.

Prediction of the biodegradability of organic compounds is an ecologically desirable and economically feasible tool for estimating the environmental fate of chemicals. We combined quantitative structure-activity relationships (QSAR) with the systematic collection of biochemical knowledge to establish rules for the prediction of aerobic biodegradation of N-heterocycles. Validated biodegradation data of 194 N-heterocyclic compounds were analyzed using the MULTICASE-method which delivered two QSAR models based on 17 activating (OSAR 1) and on 16 inactivating molecular fragments (GSAR 2), which were statistically significantly linked to efficient or poor biodegradability, respectively. The percentages of correct classifications were over 99% for both models, and cross-validation resulted in 67.9% (GSAR 1) and 70.4% (OSAR 2) correct predictions. Biochemical interpretation of the activating and inactivating characteristics of the molecular fragments delivered plausible mechanistic interpretations and enabled us to establish the following biodegradation rules: (1) Target sites for amidohydrolases and for cytochrome P450 monooxygenases enhance biodegradation of nonaromatic N-heterocycles. (2) Target sites for molybdenum hydroxylases enhance biodegradation of aromatic N-heterocycles. (3) Target sites for hydratation by an urocanase-like mechanism enhance biodegradation of imidazoles. Our complementary approach represents a feasible strategy for generating concrete rules for the prediction of biodegradability of organic compounds.

Pineapple juice labeled with gadolinium: a convenient oral contrast for magnetic resonance cholangiopancreatography.

The aim of our study was to prepare in vitro a pineapple juice (PJ) solution labeled with a minimal gadolinium concentration working as a negative contrast agent in heavily T2-weighted imaging and to assess that solution in vivo as a negative oral contrast agent for magnetic resonance cholangiopancreatography (MRCP). Three PJs were compared in vitro according to their T2. Increasing concentrations of gadolinium (Gd)-DOTA in PJ were assessed in vitro for T2 reduction. Single-shot turbo spin echo T2-weighted MR cholangiopancreatograms were obtained for 35 patients with suspected biliopancreatic duct disease, before and after ingestion of the PJ/Gd-DOTA solution. Signal intensity (SI) measurements of gastroduodenal lumens, pancreatobiliary ducts, and image quality scores were obtained systematically before and after contrast ingestion. The in vitro selected Gd-DOTA concentration in the PJ was 2.76 mmol/l. Ingestion of 180 ml of PJ labeled with 1 ml of Gd-DOTA eliminated efficiently the gastroduodenal SI in MRCP, improving significantly the rates of complete visualization of the pancreatobiliary ducts (P<0.01) and the MRCP image quality scores (P<0.05). All patients easily ingested the contrast solution and found the solution palatable. PJ labeled with gadolinium constituted an efficient and convenient negative oral contrast agent for MRCP.

Thermophilic biodesulfurization of various heterocyclic sulfur compounds and crude straight-run light gas oil fraction by a newly isolated strain Mycobacterium phlei WU-0103.

Various heterocyclic sulfur compounds such as naphtho[2,1-b]thiophene (NTH) and benzo[b]thiophene (BTH) derivatives can be detected in diesel oil, in addition to dibenzothiophene (DBT) derivatives. Mycobacterium phlei WU-0103 was newly isolated as a bacterial strain capable of growing in a medium with NTH as the sulfur source at 50 degrees C. M. phlei WU-0103 could degrade various heterocyclic sulfur compounds, not only NTH and its derivatives but also DBT, BTH, and their derivatives at 45 degrees C. When M. phlei WU-0103 was cultivated with the heterocyclic sulfur compounds such as NTH, NTH 3,3-dioxide, DBT, BTH, and 4,6-dialkylDBTs as sulfur sources, monohydroxy compounds and sulfone compounds corresponding to starting heterocyclic sulfur compounds were detected by gas chromatography-mass spectrometry analysis, suggesting the sulfur-specific desulfurization pathways for heterocyclic sulfur compounds. Moreover, total sulfur content in 12-fold-diluted crude straight-run light gas oil fraction was reduced from 1000 to 475 ppm S, with 52% reduction, by the biodesulfurization treatment at 45 degrees C with growing cells of M. phlei WU-0103. Gas chromatography analysis with a flame photometric detector revealed that most of the resolvable peaks, such as those corresponding to alkylated derivatives of NTH, DBT, and BTH, disappeared after the biodesulfurization treatment. These results indicated that M. phlei WU-0103 may have a good potential as a biocatalyst for practical biodesulfurization of diesel oil.

Impact of environmental exposures on the mutagenicity/carcinogenicity of heterocyclic amines.

Carcinogenic heterocyclic amines are produced from overcooked foods and are highly mutagenic in most short-term test systems. One of the most abundant of these amines, 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), induces breast, colon and prostate tumors in rats. Human dietary epidemiology studies suggest a strong correlation between either meat consumption or well-done muscle meat consumption and cancers of the colon, breast, stomach, lung and esophagus. For over 20 years our laboratory has helped define the human exposure to these dietary carcinogens. In this report we describe how various environmental exposures may modulate the risk from exposure to heterocyclic amines, especially PhIP. To assess the impact of foods on PhIP metabolism in humans, we developed an LC/MS/MS method to analyze the four major PhIP urinary metabolites following the consumption of a single portion of grilled chicken. Adding broccoli to the volunteers' diet altered the kinetics of PhIP metabolism. At the cellular level we have found that PhIP itself stimulates a significant estrogenic response in MCF-7 cells, but even more interestingly, co-incubation of the cells with herbal teas appear to enhance the response. Numerous environmental chemicals found in food or the atmosphere can impact the exposure, metabolism, and cell proliferation response of heterocyclic amines.

Isolation and characterization of Xanthobacter polyaromaticivorans sp. nov. 127W that degrades polycyclic and heterocyclic aromatic compounds under extremely low oxygen conditions.

Two bacterial strains, 127W and T102, were isolated from anoxic crude oil tank sludge as effective degraders of dibenzothiophene (DBT), a model sulfur containing heterocyclic aromatic compound in crude oil. Strain 127W was more tolerant to oxygen limitation than T102 and was capable of degrading two- and three-ring polycyclic and heterocyclic aromatic compounds under both aerobic and low oxygen conditions. Strain 127W degraded 0.082, 0.055, and 0.064 mM of DBT, naphthalene, and anthracene, respectively, in one week with dissolved oxygen < or =0.2ppm (0.006 mM). Degradation by 127W cell-free extracts for DBT was increased by addition of sodium hydrogencarbonate under this oxygen concentration. Phylogenetic analysis of the 16S rRNA gene sequence and physiological characteristics indicate that the strains 127W and T102 belong to new species of the genus Xanthobacter and Pseudomonas stutzeri, respectively. We propose X. polyaromaticivorans sp. nov. 127W.

Experience with indium-111 and yttrium-90-labeled somatostatin analogs.

The high level expression of somatostatin receptors (SSTR) on various tumor cells has provided the molecular basis for successful use of radiolabeled octreotide / lanreotide analogs as tumor tracers in nuclear medicine. Other (nontumoral) potential indications for SSTR scintigraphy are based on an increased lymphocyte binding at sites of inflammatory or immunologic diseases such as thyroid-associated ophthalmology. The vast majority of human tumors seem to over-express the one or the other of five distinct hSSTR subtype receptors. Whereas neuroendocrine tumors frequently overexpress hSSTR2, intestinal adenocarcinomas seem to overexpress more often hSSTR3 or hSSTR4, or both of these hSSTR. In contrast to In-DTPA-DPhe(1)-octreotide (OctreoScan(R)) which binds to hSSTR2 and 5 with high affinity (Kd 0.1-5 nM), to hSSTR3 with moderate affinity (K(d) 10-100 nM) and does not bind to hSSTR1 and hSSTR4, (111)In / (90)Y-DOTA-lanreotide was found to bind to hSSTR2, 3, 4, and 5 with high affinity, and to hSSTR1 with lower affinity (K(d) 200 nM). Based on its unique hSSTR binding profile, (111)In-DOTA-lanreotide was suggested to be a potential radioligand for tumor diagnosis, and (90)Y-DOTA-lanreotide suitable for receptor-mediated radionuclide therapy. As opposed to (111)In-DTPA-DPhe(1)-octreotide and (111)In-DOTA-DPhe(1)-Tyr(3)-octreotide, discrepancies in the scintigraphic results were seen in about one third of (neuroendocrine) tumor patients concerning both the tumor uptake as well as detection of tumor lesions. On a molecular level, these discrepancies seem to be based on a "higherrdquuo; high-affinity binding of (111)In-DOTA-DPhe(1)-Tyr(3)-octreotide to hSSTR2 (K(d) 0.1-1 nM). Other somatostatin analogs with divergent affinity to the five known hSSTR subtype receptors have also found their way into the clinics, such as (99m)Tc-depreotide (NeoSpect(R); NeoTect(R)). Most of the imaging results are reported for neuroendocrine tumors (octreotide analogs) or nonsmall cell lung cancer ((99m)Tc-depreotide), indicating high diagnostic cabability of this type of receptor tracers. Consequently to their use as receptor imaging agents, hSSTR recognizing radioligands have also been implemented for experimental receptor-targeted radionuclide therapy. Beneficial results were reported for high-dose treatment with (111)In-DTPA-DPhe(1)-octreotide, based on the emission of Auger electrons. The Phase IIa study "MAURITIUS" (Multicenter Analysis of a Universal Receptor Imaging and Treatment Initiative, a eUropean Study) showed in progressive cancer patients (therapy entry criteria) with a calculated tumor dose > 10 Gy / GBq (90)Y-DOTA-lanreotide, the proof-of-principle for treating tumor patients with peptide receptor imaging agents. In the "MAURITIUS" study, cummulative treatment doses up to 200 mCi (90)Y-DOTA-lanreotide were given as short-term infusion. Overall treatment results in 70 patients indicated stable tumor disease in 35% of patients and regressive tumor disease in 10% of tumor patients with different tumor entities expressing hSSTR. No acute or chronic severe hematological toxicity, change in renal or liver function parameters due to (90)Y-DOTA-lanreotide treatment, were reported. (90)Y-DOTA-DPhe(1)-Tyr(3)-octreotide may show a higher tumor uptake in neuroendocrine tumor lesions and may therefore be superior for treatment in patients with neuroendocrine tumors. However, there is only limited excess to long-term and survival data at present. Potential indications for (90Y-DOTA-lanreotide are radioiodine-negative thyroid cancer, hepatocellular cancer and lung cancer. Besides newer approaches and recent developments of 188)Re-labeled radioligands, no clinical results on the treatment response are yet available. In conclusion, several radioligands have been implemented on the basis of peptide receptor recognition throughout the last decade. A plentitude of preclinical data and clinical studies confirm their potential use in diagnosis as well as "proof-of-principle" for therapy of cancer patients. However, an optimal radiopeptide formulatioents. However, an optimal radiopeptide formulation does not yet exist for receptor-targeted radionuclide therapy. Ongoing developments may result in peptides more suitable for this kind of receptor-targeted radionuclide therapy.

Characterization of phenolic compounds in virgin olive oil and their effect on the formation of carcinogenic/mutagenic heterocyclic amines in a model system.

Mutagenic heterocyclic amines (HAs) are formed at low levels during cooking of meat and fish, and some of them are considered to be possible human carcinogens. The formation of HAs may be affected by the presence of synthetic or naturally occurring antioxidants. In the present study the effect of virgin olive oil (VOO) phenolic compounds, identified and quantified by LC-MS, on the formation of HAs in a model system was evaluated. An aqueous solution of creatinine, glucose, and glycine was heated in the presence of two samples of VOO differing only in the composition of phenolic compounds. The addition of VOO to the model system inhibited the formation of 2-amino-3-methylimidazo[4,5-f]quinoxaline (IQx), 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx), and 2-amino-3,7,8-trimethylimidazo[4,5-f]quinoxaline (DiMeIQx) by between 30 and 50% compared with the control. Fresh-made olive oil, which contained a high amount of dihydroxyphenylethanol derivatives, inhibited HA formation more than a 1-year-old oil did. The inhibition of HA formation was also verified using phenolic compounds extracted from VOO.