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Biomedical subjects

U Graf

Publications and source records attributed to U Graf.

At least 37 records · Page 2Linked to original sources
PubMed1995

[Neurolinguistic programming in physician-patient communication. Basic principles of the procedure--examples for application in surgery].

Neurolinguistic programming (NLP) is a means of improving physician-patient communication that can be learned by any doctor. The present article first describes some of the fundamentals of NLP and then provides examples taken from the field of surgery-in the first instance dealing with the treatment of painful conditions by means of trance or dissociation and, secondly, on the influencing of expectations and the restructuring (reframing) of doctrines in a patient with malignant disease.

Aged↗
PubMed1995

Analysis of the relationship between age of larvae at mutagen treatment and frequency and size of spots in the wing somatic mutation and recombination test in Drosophila melanogaster.

The relationship between the induction of mutant clones and the time of mutagen treatment was studied in the somatic mutation and recombination test (SMART) in wing cells of Drosophila melanogaster. Larvae trans-heterozygous for the recessive marker mutations multiple wing hairs (mwh) and flare (flr) were produced. Batches of these larvae were then treated with mutagen at different ages spanning all three larval instars. Methyl methanesulfonate was fed acutely for 2 h by immersing the larvae in a solution of the mutagen mixed with powdered cellulose. Wings of the surviving adult flies were mounted and scored for the presence of spots. The frequency and size of single and twin spots were recorded separately. Twin spots are produced exclusively by mitotic recombination, whereas single spots can result from various types of mutational and exchange events. There exists a clear correlation between time of induction and frequency as well as size of the single spots. In young larvae only few but very large spots are induced, whereas in older larvae the frequencies are considerably increased but the sizes are smaller. The twin spots show a different relationship. Practically no twin spots are found in very young and in very old larvae. The results demonstrate that in the wing spot test the optimal age of the larvae for mutagen treatment is 72 h.

Animals↗
PubMed1995

Genotoxic activity of environmentally important polycyclic aromatic hydrocarbons and their nitro derivatives in the wing spot test of Drosophila melanogaster.

The genotoxicity of three polycyclic aromatic hydrocarbons (PAHs) and of three of their nitro derivatives was evaluated in the wing Somatic Mutation And Recombination Test (SMART) in Drosophila melanogaster. Two crosses were used, i.e. the standard cross (ST) and the improved high bioactivation cross (HB) which is characterised by an increased sensitivity to the genotoxic effects of promutagens and procarcinogens. Larvae trans-heterozygous for the two recessive wing cell markers multiple wing hairs (mwh) and flare (flr3) were fed with the test compounds for 48 h. The wings of the surviving flies were analysed for the occurrence of single and twin spots. Naphthalene, 1-nitronaphthalene and 1,5-dinitronaphthalene proved to be more genotoxic in the HB cross than in the ST cross. Anthracene showed a clear genotoxic activity only in the HB cross whereas it was negative in the ST cross. 9-Nitroanthracene gave inconsistent results in both crosses. Phenanthrene was negative in the ST cross, but weakly positive in the HB cross. These results demonstrate that the genotoxic activity of these PAHs and their nitro derivatives can be detected with the somatic cells of the wing imaginal discs of larvae with high bioactivation capacity.

Animals↗
PubMed1995

Tannic acid is not mutagenic in germ cells but weakly genotoxic in somatic cells of Drosophila melanogaster.

Tannic acid (TA) was tested for genotoxic activity in three different assays (1-3) in Drosophila melanogaster by feeding of larvae or adult flies. TA did not induce sex-linked recessive lethals (1) nor sex-chromosome loss, mosaicism or non-disjunction (2) in male germ cells. In the wing somatic mutation and recombination test (SMART) (3) TA was found to be toxic for larvae of the high bioactivation cross and produced a weak positive response. These results suggest that this compound, when administered orally to larvae or adults of D. melanogaster, is not mutagenic and clastogenic in male germ cells, but weakly genotoxic in somatic cells of the wing imaginal disk.

Animals↗
PubMed1994

Time-resolved flow cytometry for the measurement of lanthanide chelate fluorescence: II. Instrument design and experimental results.

A time-resolved flow cytometer capable of measuring a luminescence with a decay time in the range of 10 microseconds to 2 ms, typical for some lanthanide chelates, is presented. The instrument permits acquisition of conventional light scatter and prompt fluorescence signals as well as detection of slowly decaying luminescence by a photon counting unit for a selectable time period of 1 microsecond to 1 ms. During photon counting, the laser beam is turned off by an acoustooptic deflector. The design of a flow chamber with an average geometrical light collection efficiency of 35% over a distance of 1.7 mm is presented and analyzed by ray tracing. A pulse processing system featuring digital integration of the conventional signals and a transputer system for the acquisition and the transfer of the measured parameter values to a host computer is described. Instrument function is verified with lyophilized human lymphocytes stained for the CD8 antigen with dye-loaded liposomes. Quantitation of cell-associated europium chelate fluorescence, displaying a decay time of 1.6 ms, is demonstrated. Elimination of fast decaying background emission generated by DNA-associated ethidium bromide is shown. The background generated by instrument components in the time-gated measurement channel is characterized, and measures for its complete elimination are discussed.

Chelating Agents↗
PubMed1994

Genotoxicity testing of different types of beverages in the Drosophila wing Somatic Mutation And Recombination Test.

Five wines and one brandy of Spanish origin as well as three herbal teas and ordinary black tea were tested for genotoxicity in the wing Somatic Mutation And Recombination Test (SMART) which makes use of the two recessive wing cell markers multiple wing hairs (mwh) and flare (flr3) on the left arm of chromosome 3 of Drosophila melanogaster. 3-day-old larvae trans-heterozygous for these two markers were fed the beverages at different concentrations and for different feeding periods using Drosophila instant medium. Somatic mutations or mitotic recombinations induced in the cells of the wing imaginal discs give rise to mutant single or twin spots on the wing blade of the emerging adult flies showing either the mwh phenotype or/and the flr phenotype. One of the red wines showed a clear genotoxic activity that was not due to its ethanol content. Two herbal teas (Urtica dioica, Achillea millefolium) and black tea (Camellia sinensis) proved to be weakly genotoxic as well. Furthermore, it was shown that quercetin and rutin, two flavonols present in beverages of plant origin, also exhibited weak genotoxic activity in the somatic cells of Drosophila. These results demonstrate that Drosophila in vivo somatic assays can detect the genotoxicity of complex mixtures such as beverages. In particular, it is possible to administer these test materials in the same form as that in which they are normally consumed.

Alcoholic Beverages↗
PubMed1993

Structure-activity relationships of tricyclic antidepressants and related compounds in the wing somatic mutation and recombination test of Drosophila melanogaster.

Four antidepressants and one neuroleptic drug were tested for genotoxicity using the somatic mutation and recombination test (SMART) in wing cells of Drosophila melanogaster. Three-day-old larvae trans-heterozygous for two linked recessive wing hair mutations (multiple wing hairs and flare) were fed the test compounds in water or solvents mixed with a standard dry food for 48 h. Wings of the emerging adult flies were scored for the presence of spots of mutant cells which can result from either somatic mutation or mitotic recombination. The tricyclic antidepressant clomipramine, which is closely related to imipramine (previously shown to be genotoxic in somatic cells of Drosophila), was clearly genotoxic at concentrations above 10 mM. The structurally related antidepressants lofepramine and mianserin were positive only at 100 mM which is the maximum tolerated dose. The antidepressant maprotiline and the antipsychotic chlorpromazine, which are distinguished from the other compounds by a 6-membered central ring instead of a 7-membered one, were not genotoxic in the same dose range. These results lend further support for the hypothesis that an N atom in the heterocyclic 7-membered ring of the tricyclic molecule is responsible for the genotoxic property of the compounds in Drosophila.

Animals↗
PubMed1992

The genotoxicity of chromium(VI) oxide in the wing spot test of Drosophila melanogaster is over 90% due to mitotic recombination.

Chromium(VI) oxide and chromium(III) chloride were tested in the wing somatic mutation and recombination test (SMART) in Drosophila melanogaster according to standard procedures. The hexavalent compound was highly genotoxic in both chronic and acute treatments whereas the trivalent one was clearly negative. Further analysis of wings carrying an inversion chromosome which eliminates all recombination events showed that over 90% of the spots induced by chromium(VI) oxide are due to mitotic recombination.

Animals↗
PubMed1992

Improved high bioactivation cross for the wing somatic mutation and recombination test in Drosophila melanogaster.

The two tester strains of the high bioactivation (HB) cross for the wing somatic mutation and recombination test (SMART) in Drosophila melanogaster developed by Frölich and Würgler possess high metabolic capacity to activate promutagens. These strains contain chromosomes 1 and 2 of the DDT-resistant stock Oregon R(R) which exhibits a high constitutive level of cytochrome P450. However, they show several disadvantages for routine application, such as disturbed wing hair patterns in certain areas of the wing, making spot classification difficult, and a delay in development of the larvae. We have established and evaluated an improved HB cross (ORR; flr3 females and mwh males) producing ORR heterozygous individuals. These develop normally and have a normal, undisturbed wing hair pattern while exhibiting high bioactivation. The hybrid larvae of the improved HB cross show P450-dependent bioactivation capacity equal to or even slightly higher than those of the original HB cross. This was demonstrated by measuring the genotoxic activity of the promutagens diethylnitrosamine, 7,12-dimethylbenz[a]anthracene, N-nitrosopyrrolidine, and urethane. In addition, the improved HB cross has a sensitivity to the direct-acting alkylating agent ethyl nitrosourea equal to that of the standard cross. The main advantage of the improved HB cross is to combine the high bioactivation capacity with the ease of scoring the wings using the same criteria as for the standard cross.

Animals↗
PubMed1992

The potential genotoxicity of sorbates: effects on cell cycle in vitro in V79 cells and somatic mutations in Drosophila.

Sodium sorbate, potassium sorbate and an oxidation product of sodium sorbate, 4,5-epoxy-2-hexenoic acid, were tested for their genotoxic potential in cultured V79 Chinese hamster cells and in somatic cells of Drosophila melanogaster (wing spot test, SMART). In Drosophila only the epoxide showed a weak genotoxic effect. In V79 cells, freshly prepared sodium sorbate solutions at the highest concentrations only (2.5 mg/ml, 24 hr exposure) arrested mitosis at the G2/M cell cycle phase and potassium sorbate (2.5 mg/ml) had no effect. This arrest was reversible after a 24-hr recovery interval. Sodium sorbate solutions stored for up to 208 days were cytotoxic at 2.5 mg/ml, induced cell cycle arrest in the G2/M phase and increased cellular protein content, indicating an action similar to spindle poisoning and a chemical stress reaction (adaptation processes, modification of transcription). Potassium sorbate solutions stored for 28 days were also cytotoxic. With 4,5-epoxy-2-hexenoic acid at concentrations up to 0.01 mg/ml no effects were seen. At higher concentrations (at least 0.1 mg/ml) cell killing was observed, which probably resulted from unphysiologically lowered pH in the culture medium. Overall, the results are interpreted as an indication of a weak genotoxic potential of stored sodium sorbate solutions. Thus, sorbic acid and its potassium salt at the concentrations used for food preservation can still be considered as safe for human consumption.

Animals↗
PubMed1992

Genotoxicity of 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) and related compounds in Drosophila.

The potent food mutagen and carcinogen 2-amino-3-methylimidazo[4,5- f]quinoline (IQ) and the structurally related heterocyclic aromatic amines 2-aminoimidazo[4,5-f]quinoline (demethyl-IQ) and 2-amino-1-methylimidazo[4,5-f]quinoline (iso-IQ) were assayed for genotoxicity in the wing somatic mutation and recombination test (SMART) as well as in the sex-linked recessive lethal (SLRL) test in Drosophila melanogaster. In addition, 3-methyl-2-nitroimidazo[4,5-f]quinoline (nitro-IQ), 2-nitrofluorene and 1,8-dinitropyrene were also assayed in the wing spot test. IQ was clearly mutagenic in the SLRL test with highest activity in spermatids. Iso-IQ was more active than IQ whereas demethyl-IQ was inactive in this test. The same pattern of results was obtained in the wing SMART: iso-IQ produced greater than 2-fold higher frequencies of spots than IQ and demethyl-IQ was clearly negative. In addition, nitro-IQ exhibited an approximately equal genotoxic activity as IQ. 2-Nitrofluorene and 1,8-dinitropyrene were both inactive in the wing spot test. These data provide good evidence for a correlation of genotoxic effects in germinal and somatic cells, and for the practical advantage of the wing spot test in Drosophila. Moreover, the results show structure-activity relationships among the heterocyclic aromatic amines and nitro compounds similar to those found in Salmonella.

Animals↗
PubMed1991

[Environmental chemicals: their clinical significance in rheumatology].

Over the past years, various illnesses including features of connective tissue disorders (e.g. systemic sclerosis, systemic lupus erythematosus, mixed connective tissue disease), and rheumatoid arthritis, seemingly related to exposure to environmental materials have been reported. This paper presents some typical case reports and review major environmental associations seen in rheumatology, along with their epidemiology, clinical and laboratory features, possible pathogenesis, prognosis, and potential therapy.

Adult↗
PubMed1991

Genotoxicity evaluation of five tricyclic antidepressants in the wing somatic mutation and recombination test in Drosophila melanogaster.

Five tricyclic antidepressants were tested for genotoxicity using the somatic mutation and recombination test (SMART) in wing cells of Drosophila melanogaster. Three-day-old larvae trans-heterozygous for 2 linked recessive wing hair mutants (multiple wing hairs and flare) were fed the test compounds in water mixed with a standard dry food for 48 h. Wings of the emerging adult flies were scored for the presence of spots of mutant cells which can be the consequence of either somatic mutation or mitotic recombination. Desipramine and imipramine were clearly genotoxic at concentrations above 1 mM whereas amitriptyline, nortriptyline and protriptyline were not genotoxic at concentrations up to 100 mM. This seems to implicate the nitrogen atom at position 5 in the 7-membered ring of the tricyclic molecule as being responsible for the genotoxic property of the compounds in Drosophila.

Amitriptyline↗
PubMed1991

The genotoxicity of nitrilotriacetic acid (NTA) in a somatic mutation and recombination test in Drosophila melanogaster.

The genotoxicity of a chelating agent, the trisodium salt of nitrilotriacetic acid (NTA), was assessed in a somatic mutation and recombination test (SMART) in Drosophila melanogaster employing the wing hair markers mwh and flr3. The experiments were performed in parallel in two different laboratories (Padua, Italy and Schwerzenbach, Switzerland). The effectively absorbed doses of NTA, which was administered by feeding to larvae, were determined by a sensitive method employing [3H]leucine which allowed individual consumption levels to be measured. The particular pattern of clone induction produced by this compound suggests that NTA is active in inducing mitotic recombination and possibly aneuploidy in somatic cells of Drosophila. This is discussed in relation to the data present in the literature regarding the genotoxicity of NTA in a variety of experimental systems.

Animals↗
PubMed1991

[The OFFER self concept questionnaire for adolescents and the success of inpatient psychotherapy].

The OFFER-Self-Image-Questionnaire reflect psychotherapeutic effects under special conditions. The OFFER-Self-Image-Questionnaire was used to evaluate outcome of in-patient psychotherapy in 15 adolescents. An increase of 8 or more points on the standard scale between the first and fourth week was associated with favourable outcome while an increase of 7 or less points indicated less favourable outcome.

Adolescent↗
PubMed1990

On the use of excision repair defective cells in the wing somatic mutation and recombination test in Drosophila melanogaster.

Ten chemical mutagens were tested in the wing somatic mutation and recombination test in Drosophila melanogaster. This assay makes use of genetic markers expressed on the wing of adult flies. Larvae which are trans-heterozygous for mwh (multiple wing hairs) and flr (flare) were fed with the compounds either acutely (2, 4, or 6 hr) or chronically (48 or 72 hr), or were treated by inhalation (1 hr). Genetic changes induced in the somatic cells of the wing imaginal discs lead to the formation of mutant clones on the wing (mwh and/or flr). Single spots are produced by point mutation, chromosome breakage, and mitotic recombination; twin spots are produced exclusively by mitotic recombination. All 10 mutagens belonging to different chemical classes were clearly positive in this assay. However, the choice of the optimal treatment conditions (concentration of compound, duration of treatment, age of larvae at treatment) is essential. Eight of the compounds were also tested in excision repair defective cells by introducing the mei-9L1 mutation into the test system. This seems not to improve the detection capacity of the assay, mainly because only small spots are found in excision repair defective wings. In addition, the frequencies of spots in these wings are enhanced four to five times, which makes the scoring more tedious. For these and other practical reasons the use of this specific cross is not recommended in the wing spot test for routine screening purposes.

Animals↗
PubMed1990

[F-waves and H-reflexes in hemispastic syndrome].

Canalized F-waves and H-reflexes occurring on small hand and foot muscles are to be considered symptoms of central disinhibition. Occurrence of these waves and reflexes in patients with hemispastic syndrome is analyzed and correlated with clinical aspects.

Adolescent↗