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U Baumann

Publications and source records attributed to U Baumann.

At least 91 records · Page 5Linked to original sources
PubMed1987

Binding of DNA hairpins to an assembler-strand as part of a primordial translation device.

A crucial event in the process leading to the origin of life is the emergence of a simple translation device. To approach experimental realization of this device the binding ability of short DNA hairpins to complementary oligonucleotides fixed on a solid support was investigated. The binding is achieved by base pairing between the loop nucleotides of the hairpins containing different numbers of adenosine residues and oligothymidylates covalently linked to cellulose. The loop has to consist of at least five nucleotides to achieve binding. The exact number of established base pairs was determined in two ways. First, the elution temperatures of hairpins and those of oligoadenylates which had the length of the loop were compared. Secondly, the architecture of the loop was analyzed by means of the single-strand-specific nuclease from mung bean acting as structural probe. Only n-2 of n loop nucleotides of a hairpin are able to form base pairs. Therefore, a strong evidence for the formation of a triplet of base pairs between primeval tRNA and mRNA sufficient to stabilize the complex enzyme-free is given.

Base Sequence↗
PubMed1986

Conformational analysis of hairpin oligodeoxyribonucleotides by a single-strand-specific nuclease.

Hairpin-forming oligodeoxynucleotides d[ATCCTA(A)NTAGGAT] with n = 3-6 were subjected to nuclease digestion with the nuclease from mung bean. Cleavage occurs only in the loop region of the hairpin molecules. In detail, the number and intensity of cleavage sites were determined in relation to the length of the loop, the temperature and the salt concentration. The restricted accessibility of mung bean nuclease to the loop bases adjacent to the helical region of all hairpins is due to a reduced exposure of these bases in presence of a certain Mg2+ concentration. With increasing temperature the exposure of these bases is increased. It is deduced that the bases adjacent to the helix increase the length of the latter by stacking, the degree of which is dependent on the number of loop bases.

Binding Sites↗
PubMed1986

[Evaluation of psychotherapy--basic research perspectives].

Four models of psychotherapy research and evaluation are presented. Eysenck's model of experimental psychology implies the call for control groups; Kiesler's model emphasizes the consideration of differential aspects regarding patients, therapists, techniques and outcome measures. Limitations of traditional models are discussed. New approaches should project psychotherapy research with reference to the phase model used in pharmacological research and take into account various perspectives for the psychotherapy field. Some data on the influence of priests/vicars and dowsers serve to exemplify the necessity of macro-research.

Evaluation Studies as Topic↗
PubMed1985

Analysis of modification-dependent structural alterations in the anticodon loop of Escherichia coli tRNAArg and their effects on the translation of MS2 RNA.

The conformation of the anticodon loop of Escherichia coli tRNAArg was investigated. It is shown that the structure of the anticodon loop is influenced by the base composition of the anticodon stem, and the natural modification of the nucleoside residue 32 in the anticodon loop. The structural effects detected by analysis of the accessibility of the anticodon loop to nuclease S1 could be correlated with the ability of different Arg-tRNAArg species to suppress frame-shifting during translation of MS2 RNA.

Anticodon↗
PubMed1985

Self-rating data as a selecting factor in clinical trials of psychotropic drugs.

In psychiatry the relationship between rating by others and self-rating has been discussed again and again. The question has been raised as to the influence of complete data material (all patients with self-rating and rating by others) on results, in comparison to results where patients without self-rating are not taken into evaluation. This question was answered by conducting a double-blind study which included two pharmacologically active substances (amitriptylinoxide and trazodone) and two sub-samples of patients (patients with rating by others and self-rating, and patients with rating by others alone). The trial was performed in a total of 57 in-patients suffering from endogenous depression (ICD 296.1) who received drug treatment for 21 days. The effect was assessed multi-methodically. While no differences between the two drugs were seen in the sub-sample "self-rating and rating by others", amitriptylinoxide proved to be superior to trazodone in the sub-sample "rating by others". On the basis of these findings the use of rating by others and self-rating procedures will be considered.

Adolescent↗
PubMed1983

Multimethodological approach in psychiatric predictor research.

The discussion of some methodological problems of predictor studies led to the following conclusions: 1. Different outcome criteria result in a different classification of patients as responders or non-responders. 2. Predictor variables and outcome criteria should be better defined. 3. The clinical relevance of a result can be estimated by calculating the proportion of explained variance. 4. Cross validation of results is necessary. 5. Changes during a test therapy of 10 days result in a relatively reliable prediction of outcome in acute schizophrenia and depression.

Antidepressive Agents↗
PubMed1981

Recent developments concerning the AMDP System. AMDP Congress 1980.

A report is given about the meeting of the Association of Methodology and Documentation in Psychiatry (AMDP), which took place in Basle from October 9-11, 1980. The meeting was divided in two parts: 1. Training seminar in psychopathology. 2. Scientific session. The following points were discussed by study groups: - The use of the AMDP-systems in diagnostics - Development of a scale in the AMDP-system - Problems of graduation of symptoms - Assessment of intact areas of the personality - Documentation of neurotic features - General problems of the measurement of changes. The results of the study groups are presented, and the future tasks of the AMDP-groups are described.

Humans↗
PubMed1980

[A comparison of four symptom lists (author's transl)].

At present there are four lists of symptoms in German (BL, FBL, BFB, KASSL) for which sufficient empirical data permit an evaluation. The BL, FBL, and BFB lists relate to items of the physiologic and physiologic/psychic fields, whereas the items of the KASSL refer more to psychic problems. With all four procedures the computation of global scores is justified by factor and item analyses, although the results of the BFB are least satisfactory. Information about reliability exists for all lists and point to favorable formal characteristics, i.e., symptom scores permit reliable assessment. The importance of symptom configurations is still ambiguous and needs further investigation. Measuring change with the four lists is a problem which is unsolved and needs further reflection. Because of its broad basis of test information the BL global score is recommended for use.

Humans↗
PubMed1979

[Interrater reliability of diagnosis, AMP syndromes and AMP symptoms (author's transl)].

Psychic disorders can be classified into three levels: symptom, syndrome, and diagnosis. For each of these levels of reference, interrater reliability has been calculated. For this purpose, 48 patients (25 depressives and 23 schizophrenics) were interviewed by two raters each and the diagnoses were registered on the AMP system (forms 3 and 4). Additionally, each rather made an ICD diagnosis. With ICD numbers of three digits interrater reliability amounted to Kappa = 0.84; with ICD numbers of four digits it amounted to Kappa = 0.65. According to the degree of accuracy, numerical agreement with the AMP syndromes lies between Kappa = 0.61 and 0.85. Single symptoms had the lowest reliability (median: Kappa 0.45 and 0.53). Reasons for these differences and possibilities for improvement are discussed.

Adolescent↗
PubMed1979

Long-term effects of interval laparoscopic sterilization by bipolar electrocoagulation on menstruation.

We studied the menstrual patterns of 258 patients before and after laparoscopic sterilization by bipolar diathermy. The observed changes were obtained were mainly related to the kind of contraception used before sterilization. The frequency of menstrual disorders after sterilization were compared to those in a control group of non-sterilized women matched for age and parity: 12--42 months after the operation, the sterilized women did not have more irregular cycles, menorrhagia, metrorrhagia, hysmenorrhea or dyspareunia than the control group but the sterilized women did have a slightly higher incidence of polymenorrhea (p less than 0.05) and menses lasting less than 3 days (p less than 0.01). We conclude that interval laparoscopic sterilization by bipolar diathermy can be recommended for patients with normal menstrual cycles.

Adult↗