ABSTRACT
Smoking cessation is necessary to reach a higher quality of life, and, for a cancer patient, it represents an important step in improving the outcome of both prognosis and therapy. Being a cancer patient addicted to nicotine may be a critical situation. We conducted a survey to monitor how many comprehensive cancer centres in Italy have an outpatient smoker clinic and which kinds of resources are available. We also inquired about inpatient services offering psychological and pharmacological support for smoking cessation, reduction, or care of acute nicotine withdrawal symptoms. What we have witnessed is a significant gap between guidelines and services. Oncologists and cancer nurses are overscheduled, with insufficient time to engage in discussion on a problem that they do not consider directly related to cancer treatment. Furthermore, smoking habits and limited training in tobacco dependence and treatment act as an important barrier and lead to the undervaluation of smokers' needs.
ABSTRACT
A cancer patient who smokes is a very fragile person and we identify in scientific literature three main areas of clinical practice and research to develop the care of smokers with cancer. (i) Telling facts: smoking impacts on the survival and on the outcomes of surgery, chemo-, radio- and biological therapies. The aim of our intervention was to enable patients to make informed choices about smoking. (ii) Offering sensitive and effective smoking cessation like an instrument of patient empowerment to motivate change in smoker patient lifestyle. (iii) Assisting smoker patients if they develop acute nicotine withdrawal symptoms. Smoking care and nicotine replacement therapy can support temporary abstinence during the inpatient stay and providing patients with an opportunity for smoking cessation can prompt a future permanent quit attempt. Comprehensive cancer centers must act like a promoter of a better smokers' care, applying guidelines to their reality and try to do more research on smokers' needs and on the resources to assist them. Only the alliance between victims of smoking addiction and health personnel can give a chance against the tobacco epidemic.
Subject(s)
Neoplasms/psychology , Smoking Cessation/methods , Behavior Therapy , Humans , Smoking Cessation/psychologyABSTRACT
A new spectrophotometric assay for the determination of the polyphenolic content of olive oil is presented. It is a substrate-recycling assay for phenolic compounds that employs tyrosinase in the presence of excess NADH. The reaction of various phenols with the enzyme produces an o-quinone, which is detected by recycling between reactions with the enzyme and NADH. The method offers some advantages over the classical methods employed to determine the polyphenolic content of olive oil, that is, ease and reproducibility of the analysis, highly increased sensitivity, and selectivity toward phenolic compounds. The amount of total polyphenols was determined in virgin olive oils both with the Folin-Ciocalteu reagent and with the proposed enzymatic method. The results suggest a better estimation of the polyphenol content, as compared with the colorimetric method. This has to be attributed to the different reactivities of the two methods toward phenols and catechols. Finally, the enzymatic method demonstrates that there is a linear relationship between the olive oil phenolic content and the antioxidative capacity of oil extracts.
Subject(s)
Flavonoids , Phenols/analysis , Plant Oils/chemistry , Polymers/analysis , Monophenol Monooxygenase/metabolism , NAD , Olive Oil , Polyphenols , Spectrophotometry/methodsABSTRACT
We followed for a period of six months, 54 patients of over 60 years old, submitted to hemodialitic treatment. We gave human recombinant erythropoietin, average dosage 50 UI/Kg subcutaneously on alternative days, folic acid and iron supplements together with a proteic supply of 1.2 g/Kg/die (35 Kcal/Kg). The medullary response has been monitored with hematochemical tests; blood pressure and nutritional conditions have been evaluated. Furthermore, the patients were given a questionnaire to evaluate their quality of life. At the end of the follow up, 50 patients responded positively to therapy. These patients showed an increase of RBC (from 2,789,780 +/- 259,310 to 3,313,110 +/- 472,780 p < 0.001) of HCT (from 21.86% +/- 2.16% to 27.18 +/- 2.74% p < 0.0001) and of Hb (from 7.72 +/- 1.12 g/dl to 9.28 +/- 0.98 g/dl p < 0.006). Total protein and albumin increased too. Furthermore they showed a progressive increase of "performance status". Our results confirm efficacy of erythropoietin in the treatment of anemia in elderly hemodialized patients.
Subject(s)
Erythropoietin/therapeutic use , Kidney Failure, Chronic/therapy , Quality of Life , Renal Dialysis , Age Factors , Aged , Aged, 80 and over , Anemia, Iron-Deficiency/drug therapy , Anemia, Iron-Deficiency/etiology , Dose-Response Relationship, Drug , Erythropoietin/administration & dosage , Female , Humans , Kidney Failure, Chronic/psychology , Male , Renal Dialysis/adverse effects , Renal Dialysis/psychologyABSTRACT
Cysteamine is oxidatively deaminated by lentil amine oxidase. It shows saturation kinetic K(m) = 9 x 10(-4) M like other substrates, but the aldehyde produced leads to loss of enzyme activity, which is restored by dialysis. When putrescine is the substrate of the amine oxidase cysteamine behaves like a competitive inhibitor, and shows Ki = 5 x 10(-5) M. The possible involvement of the oxidation of cysteamine and the inhibitory effects of thioacetaldehyde in the cystamine oxidation by amine oxidase is discussed.
Subject(s)
Amine Oxidase (Copper-Containing) , Cysteamine/metabolism , Fabaceae/enzymology , Oxidoreductases Acting on CH-NH Group Donors/metabolism , Plants, Medicinal , Cystamine/metabolism , Kinetics , Models, Chemical , Oxidation-Reduction , Oxygen/metabolismABSTRACT
Cystathionamine and lanthionamine are good substrates for lentil seedlings amine oxidase. One mole of hydrogen peroxide and one mole of ammonia per mole of substrate are produced, indicating that only one amino group is oxidized to aldehyde. The aminoaldehydes so originated undergo cyclization by intramolecular Schiff base formation. The pH optimum for the oxidation of either cystathionamine or lanthionamine is 7.0 in potassium phosphate buffer. The Km values are 0.61 and 0.84 mM respectively, similar to that for cystamine (0.8 mM).
Subject(s)
Amine Oxidase (Copper-Containing)/metabolism , Cystathionine/analogs & derivatives , Ethylamines/metabolism , Fabaceae/enzymology , Plants, Medicinal , Sulfides/metabolism , Aldehydes/metabolism , Ammonia/metabolism , Cystathionine/metabolism , Hydrogen Peroxide/metabolism , Kinetics , Oxidation-Reduction , Oxygen/metabolism , Spectrum AnalysisABSTRACT
S-(3-aminopropyl)cysteine and Se-(3-aminopropyl)selenocysteine are deaminated by bovine liver glutamine transaminase. The corresponding alpha-keto acids, S-(3-aminopropyl)-thiopyruvic acid and Se-(3-aminopropyl)selenopyruvic acid, are produced which spontaneously cyclize to ketimine derivatives. They have been identified by comparing their UV absorption spectra and some chemical or chromatographic properties with chemically synthesized authentic samples. Also S-(2-aminoethyl)homocysteine is the substrate for the enzyme. Kinetic parameters determined in comparison to thialysine and selenalysine show that neither the presence of a sulphur or a selenium atom nor the relative position of the atom in the carbon chain appreciably affects the substrate specificity of the enzyme. However, the length of the carbon chain has some influence on it.
Subject(s)
Amino Acids, Sulfur/metabolism , Amino Acids/metabolism , Selenium/metabolism , Transaminases/metabolism , Animals , Cattle , Chromatography, High Pressure Liquid , Cysteine/analogs & derivatives , Cysteine/metabolism , Keto Acids/metabolism , Kinetics , Liver/enzymology , Lysine/analogs & derivatives , Lysine/metabolism , Methionine/metabolism , Organoselenium Compounds/metabolism , Spectrophotometry, Ultraviolet , Substrate SpecificitySubject(s)
Escherichia coli/drug effects , Organoselenium Compounds , Ovary/cytology , Protein Synthesis Inhibitors/pharmacology , Selenium/pharmacology , Animals , Cells, Cultured , Cricetinae , Cricetulus , Cysteine/pharmacology , Drug Resistance , Escherichia coli/genetics , Escherichia coli/physiology , Female , Lysine/metabolism , Lysine/pharmacology , Lysine-tRNA Ligase/antagonists & inhibitors , Lysine-tRNA Ligase/metabolism , Mutation , Ovary/drug effectsABSTRACT
The intracellular transport and the activation of lysine, thialysine and selenalysine have been investigated in a thialysine-resistant CHO cell mutant strain in comparison with the parental strain. The cationic amino acid transport system responsible for the transport of these 3 amino acids shows no differences between the 2 strains as regards its affinity for each of these amino acids. On the other hand the Vmax of the transport system in the mutant is about double that in the parental strain. The lysyl-tRNA synthetase, assayed both as ATP = PPi exchange reaction and lysyl-tRNA synthesis, shows a lower affinity for thialysine and selenalysine than for lysine in both strains; in the mutant, however, the difference is even greater. Thus the thialysine resistance of the mutant is mainly due to the properties of its lysyl-tRNA synthetase, which shows a greater difference of the affinities for lysine and thialysine with respect to the parental strain.
Subject(s)
Cysteine/analogs & derivatives , Organoselenium Compounds , Adenosine Triphosphate/metabolism , Animals , Arginine/metabolism , Biological Transport , Cricetinae , Cysteine/metabolism , Cysteine/toxicity , Diphosphates/metabolism , Drug Resistance , Kinetics , Lysine/analogs & derivatives , Lysine/pharmacology , Lysine-tRNA Ligase/antagonists & inhibitors , Selenium/pharmacologyABSTRACT
CHO cells can incorporate thialysine and selenalysine in their proteins in substitution of lysine. Data are reported in the present paper showing that proteins containing either thialysine or selenalysine are unstable and quite rapidly degraded. The degradation rate is strictly related to the extent of protein lysine substitution. At similar extent of substitution, selenalysine-containing proteins are more unstable that thialysine-containing ones.
Subject(s)
Cysteine/analogs & derivatives , Lysine/analogs & derivatives , Organoselenium Compounds , Proteins/metabolism , Selenium/metabolism , Amino Acids/analysis , Animals , Cells, Cultured , Cricetinae , Cricetulus , Cysteine/metabolism , Isoleucine/metabolism , Leucine/metabolism , Lysine/metabolism , Protein Biosynthesis , Protein Hydrolysates/analysisABSTRACT
CHO cells allowed to grow in a medium containing selenalysine can utilize it for protein synthesis. Selenalysine is incorporated into cell proteins in substitution of lysine: a maximum of 5% of protein lysine can be substituted. Protein lysine substitution by selenalysine can be correlated to the reduced viability of cells grown in its presence.
Subject(s)
Lysine/analogs & derivatives , Organoselenium Compounds , Selenium/metabolism , Animals , Cell Line , Cricetinae , Cricetulus , Female , Kinetics , Lysine/metabolism , Lysine/pharmacology , OvaryABSTRACT
Data reported in this paper show that both lysine transport systems in E. coli KL16 can be repressed by lysine and its isologs, thialysine and selenalysine, whereas they are not repressed by ornithine. The repression is specific on lysine transport systems; it is evident with 0.01 mM lysine or isolog concentration and reaches a maximum with 0.1 mM concentration. By comparing the extent of repression by lysine and its isologs, lysine gives the highest and selenalysine the lowest degree of repression. The shift from the repressed to the depressed state is rather immediate once the amino acid is removed from the culture medium.
Subject(s)
Escherichia coli/metabolism , Lysine/metabolism , Organoselenium Compounds , Biological Transport/drug effects , Cysteine/analogs & derivatives , Cysteine/pharmacology , Kinetics , Lysine/analogs & derivatives , Lysine/pharmacology , Ornithine/pharmacology , Selenium/pharmacologySubject(s)
Aspartate Kinase/antagonists & inhibitors , Cysteine/analogs & derivatives , Escherichia coli/enzymology , Lysine/analogs & derivatives , Organoselenium Compounds , Phosphotransferases/antagonists & inhibitors , Selenium/pharmacology , Cysteine/pharmacology , Escherichia coli/drug effects , Hot Temperature , Kinetics , Lysine/pharmacologyABSTRACT
Selenalysine can be utilized in substitution of lysine by a lysine requiring E. coli mutant. The presence of some lysine in the culture medium is necessary to allow selenalysine utilization for growth; in the presence of an excess of lysine, selenalysine is not utilized. When utilized, selenalysine gives rise to an increase of final growth. However, it shows some toxic effects as demonstrated by the decrease of both growth rate and cell viability. Selenalysine is incorporated into proteins in substitution of lysine. Up to a maximum of 50% of total protein lysine can be substituted. The decrease of cell viability is correlated with the extent of lysine substitution.
Subject(s)
Escherichia coli/growth & development , Lysine/analogs & derivatives , Lysine/metabolism , Mutation , Organoselenium Compounds , Protein Biosynthesis , Selenium/metabolism , Cell Division , Escherichia coli/metabolismSubject(s)
Amino Acids/metabolism , Organoselenium Compounds , Proline/analogs & derivatives , Selenium/metabolism , Sulfur/metabolism , Animals , Escherichia coli/metabolism , Kinetics , Liver/metabolism , Lysine/analogs & derivatives , Lysine/metabolism , Proline/metabolism , Rats , Reticulocytes/metabolism , Structure-Activity RelationshipABSTRACT
The presence of selenalysine in the culture medium at concentration ranging from 0.05 to 0.3 mM inhibits Escherichia coli growth rate and cell viability. The inhibition of cell growth rate can be imputed to the inhibition of protein synthesis and can be only partially reverted by lysine. Selenalysine is incorporated into cellular proteins in substitution of and in competition with lysine, reaching the value of about 1% as molar fraction with respect to the total amino acids, and substituting up to 14% of protein lysine. The effect of selenalysine on cell viability can be correlated to the extent of its incorporation into proteins, and can be completely reverted by lysine. However, substitution up to 5% of protein lysine by selenalysine does not affect the viability, thus indicating that some degree of substitution can be well tolerated by the cell.
Subject(s)
Bacterial Proteins/biosynthesis , Escherichia coli/growth & development , Lysine/analogs & derivatives , Organoselenium Compounds , Selenium/metabolism , Cell Survival/drug effects , Escherichia coli/metabolism , Kinetics , Lysine/metabolism , Lysine/pharmacology , Selenium/pharmacologyABSTRACT
Beta-Selenaproline, a proline analog having the beta-methylene group substituted by a selenium atom, has been tested in ATP-PPi exchange reaction catalyzed by either Escherichia coli or rat liver aminoacyl-tRNA synthetases. It has been shown that with both enzymatic systems beta-selenaproline does not give rise to ATP-PPi exchange, but specifically inhibits proline activation. The inhibition is of fully competitive type and the Ki values, lower than the Km values for proline, show that beta-selenaproline binds to the synthetases with high affinity. The inability to form the complex with AMP, taking into account also the behavior of gamma-selenaproline and other proline analogs, has been ascribed to the presence of the selenium atom in the beta-position.
Subject(s)
Organoselenium Compounds , Proline/analogs & derivatives , Proline/metabolism , Selenium/pharmacology , Adenosine Triphosphate/metabolism , Amino Acyl-tRNA Synthetases/metabolism , Animals , Diphosphates/metabolism , Escherichia coli/enzymology , Kinetics , Liver/enzymology , Proline/pharmacology , Rats , Selenium/metabolismABSTRACT
Details are reported for the synthesis of Se-carboxymethylselenohomocysteamine from selenohomocysteamine and monochloroacetic acid. Data on its behaviour on paper and ion-exchange chromatography are also reported, which allow its identification.
Subject(s)
Cysteamine/analogs & derivatives , Organoselenium Compounds , Selenium/chemical synthesis , Acetates , Amino Acids/analysis , Chemical Phenomena , Chemistry , Chromatography, Ion Exchange , Chromatography, Paper , Cysteamine/chemical synthesis , Cysteine/analogs & derivatives , Selenocysteine/analogs & derivatives , Spectrophotometry, InfraredABSTRACT
CMSeC labeled with 14C in the carboxymethyl moiety was incubated with snake venom L-aminoacid oxidase. As the product of the reaction only one ketoacid was detected, which retained all the radioactivity of the oxidized substrate. This clearly shows that no breakdown of the C-Se bond of CMSeC occurs during its oxidation, and confirms previously reported data indicating that the ketoacid arising from CMSeC is CMSeP.