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[Effect of an additional cathode on the electrolytic-polishing of titanium specimens with non-aqueous electrolyte].

The purpose of this study was to polish electrolytically a large maxillary denture base-shaped titanium specimen with non-aqueous electrolyte. The test specimen was prepared by bending a sheet of titanium plate. An additional cathode was made by cutting off part of a cylindrical cathode. The effects of the shape and position of the additional cathode were investigated. Selected factors of the additional cathode were as follows: the connecting point between the additional cathode and the cylindrical cathode, the end position of the additional cathode, and the distance between the additional cathode and the titanium specimen. An acceptable polished titanium surface was obtained when the connecting point was below the electrolyte surface, the end position of the additional cathode was at a similar level to the bottom of the specimen, and the distance between the additional cathode and the specimen was 10 mm.

Dental Polishing↗

[Isolation and verification of Triticum aestivum-Eremopyrum orientale addition lines and substitution lines by GISH].

Eremopyrum is a potential genus in wheat improvement. To breed T. aestivum-Er. orientale additional and substitutional lines, chromosome number of 96 BC2F3 individuals were accounted. Fifteen plants with 2n = 43 and eight plants with 2n = 44 were checked out. GISH results of the individuals with 43 chromosomes showed that they blonged to three different monosomic additions. Two disomic additions, one double-monosomic addition, one trible-monosomic addition and one monosomic addition were found in the 2n = 44 individuals. One double-monosomic substitution and one monosomic substitution were obtained. We also proved that it is relatively easier to obtain addition lines in the selfing population than to obtain double-monosomic additions.

In Situ Hybridization↗

Continuous addition of adenosine with a micropump system improves warm whole blood cardioplegia.

BACKGROUND: Micropump additive systems allow for continuous modification of cardioplegia composition during heart surgery. Although the use of such systems in warm heart surgery is theoretically desirable, the role of the systems has been clinically limited by coronary vasoreactivity with higher potassium concentration and unreliable mechanical arrest at lower potassium concentration. Adenosine, a potent coronary vasodilator and arresting agent, has the potential to reduce the potassium concentration required for arrest and to improve distribution of cardioplegia. However, clinical use of adenosine has been limited by a short half-life in blood and difficulty in titrating the dose. This study tested the hypothesis that continuous addition of adenosine with an in-line linear micropump system would facilitate whole blood hyperkalemic perfusion for cardiac surgery. METHODS: Canine hearts (n = 9) were randomized to 20 minutes of arrest with whole blood cardioplegia or cardioplegia with adenosine at either low (0.5 M) or high (8 M) concentration. Potassium was supplemented at an arresting dose (24 mEq/L) for 5 minutes and then at a maintenance dose (6 mEq/L) for an additional 15 minutes. Coronary flow was held constant (4 mL/kg per minute), and aortic root pressure was measured. Myocardial performance was assessed by measurement of the end-diastolic pressure to stroke volume relationship at constant afterload. Myocardial tissue perfusion was evaluated with colored microspheres. RESULTS: During the initial period of high-concentration potassium arrest, coronary resistance rose progressively regardless of adenosine addition. Coronary resistance remained elevated during the period of low potassium perfusion, except when high-concentration adenosine was added. With addition of 8 M adenosine, coronary resistance returned to baseline, and left ventricular endocardial perfusion was augmented. Electromechanical quiescence improved with adenosine perfusion and was complete with high-dose adenosine addition. Function was preserved in all hearts. CONCLUSION: Use of a modern micropump system allowed for continuous addition of adenosine and potassium to whole blood cardioplegia. Adenosine minimized potassium-induced coronary vasoconstriction and improved endocardial perfusion and mechanical quiescence. These findings supported addition of adenosine to the perfusate during warm whole blood cardioplegia.

Adenosine↗

Non-additive genetic effects in animal selection.

Genetic evaluation of purebred farm animals has been carried out for about half a century, employing additive approximation to describe the genetic background. An evaluated animal has been attributed a single breeding value for each trait of the breeding goal. The predicted additive genetic value of an animal equals the average breeding value of its parents. Although the selection based on the additive approach has proved successful, there still is a possibility of increasing the reliability of the breeding value estimation by accounting for non-additive genetic effects of dominance and epistasis, disregarded in the additive model. In the non-additive model, the expected quality of the progeny equals the average of the parents plus an effect resulting from the interaction between the parents. In this case, the evaluated animal may have as many breeding values as there are possible candidates to mate to, for each trait. The dominance and epistatic effects have already been accounted for in selecting animals or populations for some crossbreeding plans (combining ability, heterosis, and recombination loss). Also, using crossbreds for the sake of the breeding value estimation of purebred animals requires removing the non-additive effects from the crossbred performance and distributing the additive component between the purebreds. Combining ability is more and more discussed as a factor for matings within breed to produce terminal progeny.

Journal Article↗

[Influence of water-soluble additives on drug release kinetics from biodegradable poly(lactic-co-glycolic acid) matrix].

AIM: To evaluate the effects of an array of additives on drug release from double-layered poly(lactic-co-glycolic acid) (PLGA) matrices. METHODS: Additives differing in molecular size, hydrophilicity and steric configuration were selected for this study. An anti-proliferative 2-aminochromone, U-86983 (U-86, Pharmacia and Upjohn), was used as a model agent because of our interest in investigating local drug delivery systems for the inhibition of restenosis. RESULTS: In vitro release of U-86 PLGA matrices without additive showed a typical biphasic release kinetics, i.e. a slow diffusion release (Phase I) followed by a fast erosion-mediated release (Phase II). The water-soluble additives in PLGA matrices changed the biphasic release pattern to a near monophasic profile by increasing the release of the Phase I. Increasing the ratio of additives to PLGA in matrices caused a significant increase in U-86 release rates. A high molecular weight water-soluble additive, Pluronic F127, resulted in a matrix showing perfect zero-order release kinetics. The morphologic evaluation of matrices using scanning electron microscopy indicated that the water-soluble additives were leachable and thus generated a highly porous structure in the matrices. Conclusion Water-solubility, molecular size and steric configuration of additives are the important determinants in generating various types of pore structures in polymer matrix which in turn affect the release mechanism and release kinetics.

Biocompatible Materials↗

Poor outcome in patients treated with brachytherapy for diffuse in-stent restenosis. The role of additional stenting despite prolonged antiplatelet therapy.

BACKGROUND: Brachytherapy (IBT) has been the first effective treatment of in-stent restenosis (ISR). However, when IBT is associated with additional stenting, high rates of late thrombosis have been observed. Even though prolongation of a double antiplatelet therapy seems to have overcome this problem, studies analyzing whether additional stenting still remains a negative prognostic factor for restenosis are lacking. AIM: To evaluate outcomes of patients treated for ISR with or without additional stenting and IBT followed by prolonged antiplatelet therapy. METHODS: Seventy-seven consecutive patients treated with beta radiation in 89 lesions with ISR were analyzed according to the need for deploying additional stents: 73 lesions were treated without additional stents (Group 1) and 16 lesions with one or more new stents (Group 2) because of suboptimal results or flow-limiting dissections. Double antiplatelet therapy was administered for 12 months. An angiographic follow-up was scheduled after 6 months. P-values < 0.05 were considered significant. RESULTS: Restenosis rates were 31.5% (23/73) and 62.5% (10/16) in Group 1 (G1) and Group 2 (G2), respectively (p = 0.02). The two groups did not differ for late vessel thrombosis (8 in G1 and 2 in G2). In G2, high rates of recurrence were observed in the additional stent (6/16, 37.5%; p = 0.02 versus edge restenosis and in old stent recurrence in both G1 and G2). CONCLUSIONS: The association of additional stenting with brachytherapy in treatment of ISR is characterized by poor outcomes, even if a prolonged antiplatelet therapy has been administered. These results are related to high restenosis rates observed in the additional stent.

Aged↗

[Studies on newly improved gallium alloy as dental restorative material, by addition of SiC whisker and titanium powder].

Studies on new gallium alloy using liquid alloy of Ga-Sn-In which was stable at room temperature and with Ag-Sn-Cu-Pd-Zn alloy as powder, were undertaken. Two kinds of gallium alloy by addition of SiC whisker and titanium powder were made on an experimental basis for the purpose of improving the property of this alloy (reinforced alloy). Physical properties such as compressive strength, diametral tensile strength, dimensional change and chemical properties such as discoloration, corrosion, quantitative analysis by Inductively Coupled Plasma were measured. Furthermore breakage surface of alloy after tensile test was observed with SEM. The effect of adding SiC whisker and titanium powder to gallium alloy was discussed and the conclusions were as follows; 1) Compressive strength: Initial strength decreased due to addition of SiC whisker and titanium powder. However, it showed a tendency to increase as time elapsed. It approached the same degree of compressive strength after 7 days. 2) Diametral tensile strength: The best results were obtained by addition of 1% SiC whisker to gallium alloy and the optimum trituration time was 13 seconds in this study. 3) Dimensional change: Expansion in the dimensional change was observed in all testing groups which was slightly over the limitation of ISO and ADA No.1 specification. 4) Discoloration: In the case with addition of titanium powder to gallium alloy, an improvement of discoloration was manifested in artificial saliva and 1% NaS, especially prominent in the former. The favorable results were obtained by addition of 10% titanium powder to gallium alloy for discoloration tolerance. 5) Corrosion: The corrosion was low in four kinds of test immersion liquid. The best results were obtained by addition of 10% titanium powder to gallium alloy. 6) Quantitative analysis by Inductively Coupled Plasma: The examined amount of Zn dissolved out from core composition was decreased due to addition of titanium powder. An improvement of amount in dissolution of Ga, Sn and In from matrix was recognized. 7) In physical and chemical experiment's results, it was judged that the addition of 0.5-0.7% SiC whisker and 5-10% titanium powder was useful.

Copper↗

Evaluation of certain food additives and contaminants.

This report represents the conclusions of a Joint FAO/WHO Expert Committee convened to evaluate the safety of various food additives and contaminants, with a view to recommending Acceptable Daily Intakes (ADIs) and tolerable intakes, respectively, and to prepare specifications for the identity and purity of food additives. The first part of the report contains a general discussion of the principles governing the toxicological evaluation of food additives and contaminants (including flavouring agents), and the establishment and revision of specifications. A summary follows of the Committee's evaluations of toxicological data on various specific food additives (furfural, paprika oleoresin, caramel colour II, cochineal extract, carmines, aspartame-acesulfame salt, D-tagatose, benzoyl peroxide, nitrous oxide, stearyl tartrate and trehalose), flavouring agents and contaminants (cadmium and tin), and of intake data on calcium from calcium salts of food additives. Annexed to the report are tables summarizing the Committee's recommendations for ADIs of the food additives and tolerable intakes of the contaminants considered, changes in the status of specifications of these food additives and specific flavouring agents, and further information required or desired.

Flavoring Agents↗

Food additives.

The use of additives to food fulfils many purposes, as shown by the index issued by the Codex Committee on Food Additives: Acids, bases and salts; Preservatives, Antioxidants and antioxidant synergists; Anticaking agents; Colours; Emulfifiers; Thickening agents; Flour-treatment agents; Extraction solvents; Carrier solvents; Flavours (synthetic); Flavour enhancers; Non-nutritive sweeteners; Processing aids; Enzyme preparations. Many additives occur naturally in foods, but this does not exclude toxicity at higher levels. Some food additives are nutrients, or even essential nutritents, e.g. NaCl. Examples are known of food additives causing toxicity in man even when used according to regulations, e.g. cobalt in beer. In other instances, poisoning has been due to carry-over, e.g. by nitrate in cheese whey - when used for artificial feed for infants. Poisonings also occur as the result of the permitted substance being added at too high levels, by accident or carelessness, e.g. nitrite in fish. Finally, there are examples of hypersensitivity to food additives, e.g. to tartrazine and other food colours. The toxicological evaluation, based on animal feeding studies, may be complicated by impurities, e.g. orthotoluene-sulfonamide in saccharin; by transformation or disappearance of the additive in food processing in storage, e.g. bisulfite in raisins; by reaction products with food constituents, e.g. formation of ethylurethane from diethyl pyrocarbonate; by metabolic transformation products, e.g. formation in the gut of cyclohexylamine from cyclamate. Metabolic end products may differ in experimental animals and in man: guanylic acid and inosinic acid are metabolized to allantoin in the rat but to uric acid in man. The magnitude of the safety margin in man of the Acceptable Daily Intake (ADI) is not identical to the "safety factor" used when calculating the ADI. The symptoms of Chinese Restaurant Syndrome, although not hazardous, furthermore illustrate that the whole ADI cannot always be ingested as a single dose on an empty stomach with impunity.

Animals↗

The application of in vitro data in the derivation of the acceptable daily intake of food additives.

The acceptable daily intake (ADI) for food additives is commonly derived from the NOAEL (no-observed-adverse-effect level) in long-term animal in vivo studies. To derive an ADI a safety or uncertainty factor (commonly 100) is applied to the NOAEL in the most sensitive test species. The 100-fold safety factor is considered to be the product of both species and inter-individual differences in toxicokinetics and toxicodynamics. Although in vitro data have previously been considered during the risk assessment of food additives, they have generally had no direct influence on the calculation of ADI values. In this review 18 food additives are evaluated for the availability of in vitro toxicity data which might be used for the derivation of a specific data-derived uncertainty factor. For the majority of the food additives reviewed, additional in vitro tests have been conducted which supplement and support the short- and long-term in vivo toxicity studies. However, it was recognized that these in vitro studies could not be used in isolation to derive an ADI; only when sufficient in vivo mechanistic data are available can such information be used in a regulatory context. Additional short-term studies are proposed for the food additives which, if conducted, would provide data that could then be used for the calculation of data-derived uncertainty factors.

Animals↗

Chemical interactions between additives in foodstuffs: a review.

This paper critically reviews the key literature on food additive-additive chemical interactions published over the last 30 years together with appropriate relevant information on food additive-food component interactions. Five main classes of food additive are included, reflecting the research effort to date: the sulfur (IV) species of preservatives, synthetic food colouring materials, nitrate and nitrite, ascorbic acid, and sorbic acid. Within each class, aspects of the chemistry (reactivity), functionality, stability, use and reactions with other specific food additives are reviewed. Where appropriate, the importance of interactions of food additives with other components of food (i.e. nutrients and non-nutrients) has been assessed and certain aspects of toxicology included. The practical outcome of this review is presented as a set of recommendations for future research in this area. The use of the data in this review is proposed as a training set to develop the framework into a diagnostic tool. This might be used ultimately for the development of a multilevel framework, operating systematically, to understand the important parameters that dictate the outcome of additive interactions.

Drug Interactions↗

Combination of antagonistic yeasts with two food additives for control of brown rot caused by Monilinia fructicola on sweet cherry fruit.

AIMS: To evaluate beneficial effect of two food additives, ammonium molybdate (NH4-Mo) and sodium bicarbonate (NaBi), on antagonistic yeasts for control of brown rot caused by Monilinia fructicola in sweet cherry fruit under various storage conditions. The mechanisms of action by which food additives enhance the efficacy of antagonistic yeasts were also evaluated. METHODS AND RESULTS: Biocontrol activity of Pichia membranefaciens and Cryptococcus laurentii against brown rot in sweet cherry fruit was improved by addition of 5 mmol l(-1) NH4-Mo or 2% NaBi when stored in air at 20 and 0 degrees C, and in controlled atmosphere (CA) storage with 10% O2 + 10% CO2 at 0 degrees C. Population dynamics of P. membranefaciens in the wounds of fruit were inhibited by NH4-Mo at 20 degrees C after 1 day of incubation and growth of C. laurentii was inhibited by NH4-Mo at 0 degrees C in CA storage after 60 days. In contrast, NaBi did not significantly influence growth of the two yeasts in fruit wounds under various storage conditions except that the growth of P. membranefaciens was stimulated after storage for 45 days at 0 degrees C in CA storage. When used alone, the two additives showed effective control of brown rot in sweet cherry fruit and the efficacy was closely correlated with the concentrations used. The result of in vitro indicated that growth of M. fructicola was significantly inhibited by NH4-Mo and NaBi. CONCLUSION: Application of additives improved biocontrol of brown rot on sweet cherry fruit under various storage conditions. It is postulated that the enhancement of disease control is directly because of the inhibitory effects of additives on pathogen growth, and indirectly because of the relatively little influence of additives on the growth of antagonistic yeasts. SIGNIFICANCE AND IMPACT OF THE STUDY: The results obtained in this study suggest that an integration of NH4-Mo or NaBi with biocontrol agents has great potential in commercial management of postharvest diseases of fruit.

Ascomycota↗

Increased osmolality of breast milk with therapeutic additives.

AIM: To evaluate the changes in the osmolality of expressed breast milk (EBM) after the addition of seven additives and four proprietary fortifiers commonly used during neonatal intensive care. METHODS: The osmolality of 5 ml EBM was measured with increasing doses of 6% NaCl, caffeine, sodium ironedetate, folic acid, and multivitamin drops. Sodium acid phosphate and chloral hydrate were added to 8 ml EBM, and the fortifiers were added to standard volumes of EBM. Dose-effect curves were plotted, and the volume of milk that must be added to the above additives to maintain osmolality below 400 mOsm/kg was calculated. RESULTS: The osmolality of the pure additives ranged from 242 to 951 mOsm/kg. There was a significant increase in the osmolality of EBM with increasing doses of all additives except caffeine. The osmolality of EBM with many additives in clinically used dosages potentially exceeded 400 mOsm/kg. The greatest increase occurred with sodium ironedetate syrup, where the osmolality of EBM increased to 951.57 (25.36) mOsm/kg. Proprietary fortifiers increased the osmolality of EBM to a maximum of 395 mOsm/kg. CONCLUSION: Routine additives can significantly increase the osmolality of EBM to levels that exceed current guidelines for premature infant feeding. A simple guide for clinical use is presented, which indicates the amount of milk required as diluent if hyperosmolality is to be avoided.

Dose-Response Relationship, Drug↗

Prevalence of food additive intolerance.

1. The existing prevalence estimates of food additive intolerance are being reviewed. 2. In the EEC report the estimated frequency of food additive intolerance is 0.03% to 0.15% based on data from patient groups. 3. The British population study results in a prevalence estimate of 0.026%. The challenged population is 81 children and adults with a history of reproducible clinical symptoms after ingestion of food additives. 4. In the Danish population study a prevalence of 1-2% is found in children age 5-16. In this study a total of 606 children mainly with atopic disease have been challenged. 5. The prevalence estimates vary with a factor 100. As the results vary so do the study populations. 6. If the different study populations are accounted for, a common conclusion can be drawn: Food additive intolerance is found in adults with atopic symptoms from the respiratory tract and skin. The prevalence estimates are questionable but may be less than 0.15%. In adults and children with reproducible, and with more subjective symptoms, such as headache and behavioural/mood change the prevalence is even lower (0.026%). Food additive intolerance is primarily found in atopic children with cutaneous symptoms where the additive is aggravating an existing disease. The prevalence of food additive intolerance in children age 5-16 is 1-2%.

Adolescent↗

Effects of alcohols and food additives on glutamate receptors expressed in Xenopus oocytes: specificity in the inhibition of the receptors.

To study the effects of food additives on glutamate receptors, they were expressed in Xenopus oocytes that received an injection of poly(A)+ mRNAs prepared from rat brain. The response of the receptors elicited by kainate (KA) and N-methyl-D-aspartate (NMDA) was measured electrophysiologically in the presence and absence of food additives. Both responses elicited by KA and NMDA were inhibited similarly by addition of additives such as caffeine, vanillin or saccharin. However, inhibition of KA-elicited response by food additives followed a competitive inhibition scheme with two binding sites, while that of NMDA-elicited response followed a simple noncompetitive inhibition scheme. Inhibition constants of food additives for both responses were more than 1 mM. So it is unlikely that food additives taken with processed food interrupt signal transmission under physiological conditions. The specificity of inhibition of both responses was examined by adding various compounds to the bathing solutions containing the agonist. Increase of the number of hydroxyl groups in alcohols with the chain of three carbon atoms decreased the potency of inhibition. Potency of the inhibition depended on the species of functional groups. The order of potency of the inhibition by compounds with a chain of six carbon atoms was alcohol = diamine > aldehyde > carboxylic acid. Hexanol inhibited the receptors more strongly than (3Z)-hexen-1-ol. NMDA-elicited response showed little selectivity in inhibition by structural isomers of pentanol, while KA-elicited response showed some selectivity in inhibition by the structural isomers.

Alcohols↗

Whole rolled sunflower seeds with or without additional limestone in lactating dairy cattle rations.

Thirty lactating Holstein cows were in a continuous trial from 21 to 120 days postpartum to evaluate diets containing whole, rolled sunflower seeds with or without additional limestone. Cows were fed individually total mixed rations of (dry matter) 47% corn silage, 9% alfalfa hay, and 44% concentrate. Concentrates were corn and soybean meal (control); corn, soybean meal, and 22% sunflower seeds; or corn, soybean meal, and sunflower seeds plus 3.5% additional limestone. Milk yield (32.2, 32.0, and 32.8 kg/day) was similar among rations. Yield of 4% fat-corrected milk was lower for cows fed sunflower seeds without additional limestone (30.2, 28.1, and 30.2 kg/day) because of lower milk fat percentages (3.57, 3.19, and 3.51). Milk protein percentage tended to be lower for cows fed sunflower seeds with additional limestone (3.01, 2.97, and 2.90). Milk, flavor score was acceptable but tended to be lower for milk from cows fed sunflower seeds with additional limestone (8.4, 8.5, and 7.9). Milk fat from cows fed sunflower seed rations contained less carbon-14:0, 16:0, and 16:1 fatty acids but more carbon-18:0. Dry matter intakes were 21.0, 18.4, and 20.0 kg/day. Dry matter digestibilities, body weight changes, and ruminal volatile fatty acid concentrations were similar among treatments. Total cholesterol in blood serum was elevated in cows fed sunflower seed rations. Insoluble salts of fatty acids were increased in ruminal fluid dry matter from cows fed sunflower seeds but were not increased further by additional limestone. Concentrations of nonesterified carbon-18:1 fatty acids in ruminal fluid dry matter were lower for cows fed sunflower seeds with additional limestone.

Animal Feed↗

Evaluation of certain food additives and contaminants.

This report represents the conclusions of a Joint FAO/WHO Expert Committee convened to evaluate the safety of various food additives and contaminants, with a view to recommending Acceptable Daily Intakes (ADIs) and tolerable intakes, respectively, and to prepare specifications for the identity and purity of food additives. The first part of the report contains a general discussion of the principles governing the toxicological evaluation of food additives (including flavouring agents) and contaminants, assessments of intake, and the establishment and revision of specifications for food additives. A summary follows of the Committee's evaluations of toxicological and intake data on various specific food additives (diacetyltartaric and fatty acid esters of glycerol, quillaia extracts, invertase from Saccharomyces cerevisiae, beta-carotene from Blakeslea trispora, curcumin, phosphates, diphosphates and polyphosphates, hydrogenated poly-1-decene, natamycin, D-tagatose, carrageenan, processed Eucheuma seaweed, curdlan, acetylated oxidized starch, alpha-cyclodextrin and sodium sulfate), flavouring agents and contaminants (3-chloro-1,2-propanediol, 1,3-dichloro-2-propanol, and a large number of polychlorinated dibenzodioxins, polychlorinated dibenzofurans and coplanar polychlorinated biphenyls). Annexed to the report are tables summarizing the Committee's recommendations for ADIs of the food additives and tolerable intakes of the contaminants considered, changes in the status of specifications of these food additives and specific flavouring agents, and further information required or desired.

Animals↗

[Frequency of food additives in mass-consumed food products].

In the effected study we wanted to reveal the richest foods in additives and the most frequent used additives. As material we used a sample formed from 100 food products investigated in a supermarket, and the method consisted in data registration of food additives written on the labels of the original packages with statistical analysis. We could not establish the food additive concentrations in foods because we have no adequate technology. The food groups with the most additives were: meat products (8 types), soft drinks (7), hydrogenated fats and sugar products (6). The most frequent used food additives were: for meat products--support substances (63%); soft drinks--acid, flavor (100%) and preserve (88%) substances; hydrogenated fats--emulsion, flavor, color substances (100%) and for sugar products--emulsion (85%) and flavor substances (78%). In conclusion, food additives with possible noxious effects on health are frequently incorporated in food products.

Diet Surveys↗