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Biomedical subjects

A Schreiner

Publications and source records attributed to A Schreiner.

At least 19 recordsLinked to original sources
PubMed1995

[Problem-oriented learning at the Göttingen University. Report of a 1 week introductory conference ("sample course")].

In Germany, a reform of the medical academic training is hotly discussed. However, only a few teachers and students can base their arguments on practical experience with new learning methods. Therefore, a one-week-try-out course ("Schnupperkurs Reformstudiengang") was organised at the university of Göttingen to gain experience in the problem-based learning. Tutorials took place according to the principle of the "seven steps" as practised in Maastricht. The students developed their own learning goals guided by a tutor. The acquiring of the subject was achieved by private studies, accompanying seminars, and practical training. An evaluation of the student's opinions on problem based learning and their satisfaction with the course was carried out by a questionnaire and group discussions. Our experiences show an open-mindedness of the academic staff and real enthusiasm on the part of the 21 participating students. Substantial for this success are--according to the results of the survey--the following items: The problem-orientated practical and interdisciplinary approach and teaching in small groups, which enabled a very close relationship between academic staff and students. A try-out-course might be a welcome entry to new forms of learning, because it offers practical experiences in new learning and teaching methods to open-minded lecturers and students. Therefore, such courses can contribute to an evolution at universities as they slowly but smoothly generate the essential competence needed to reform the medical education.

Attitude of Health Personnel↗
PubMed1994

[Diagnostic and prognostic implications of the first epileptic seizure in adulthood].

Actual epidemiological studies show a prevalence rate for active epilepsy in 0.5-1%, whereas single seizures occur in up to 5% of the general population. Assessment of the significance of first epileptic reaction requires precise definition and classification of the episode, a careful analysis of the entire context including thorough case history, and indirect anamnesis. The value of EEG-techniques for this issue is part of a controversial discussion. By means of cranial computerized tomography (cCT), brain tumours were detected as structural correlate in 5 to 16% of first-seizure-patients. In recent studies, estimated risk of seizure recurrence after first unprovoked seizure ranged from 27% to 78%: most of the relapses were observed in the first 6 months after the first event. The wide range of relapse rates is due to the divergent methodological designs (retro- versus prospective design, selection of patients, length of time before study entry) in the different studies. There are conflicting results concerning risk factors and predictive value of the following variables: pathology in the neurostatus, focal seizure type or Todd's paresis, history of febrile seizures, symptomatic genesis, and specific epileptic potentials and time of day of seizure event. In an actual metaanalysis of recent studies, seizure etiology and EEG were the strongest predictors of recurrence. The preliminary results of our prospective study with a strict protocol and first-seizure-design are presented: we observed a seizure relapse in 26.7% of 78 adult patients (age range: 17-84 years) after a mean latency of 4.4 months. Until now, there is no evidence for potential predictors of seizure recurrence.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1994

AIDS education for primary school children in Tanzania: an evaluation study.

OBJECTIVE: To test the effects of an HIV/AIDS education program. DESIGN: A quasi-experimental, nested cross-sectional design including baseline and 6-month follow-up surveys. Schools, stratified according to location, were randomly assigned to intervention (n = 6) or comparison conditions (n = 12). SETTING: Public primary schools in Arusha and Kilimanjaro regions, Tanzania. PARTICIPANTS: A total of 2026 sixth and seventh grade pupils (average age, 14.0 years) participated at baseline (85%) and 1785 at follow-up. INTERVENTION: The program was designed to reduce children's risk of HIV infection and to improve their tolerance of and care for people with AIDS. Local teachers and health workers attended a 1-week training workshop before implementing the program over a 2-3-month period (averaging 20 school hours per class). MAIN OUTCOME MEASURES: Self-reported exposure to AIDS information, communication regarding AIDS; AIDS knowledge, attitudes towards people with AIDS, attitudes towards having sexual intercourse, subjective norms regarding sexual intercourse, and intention to engage in sexual intercourse. RESULTS: Following this program, intervention pupils reported significantly higher scores for the following outcome measures than pupils attending the comparison schools: AIDS information (13.1 versus 10.5; P = 0.0001), AIDS communication (10.9 versus 7.8; P = 0.0001) AIDS knowledge (14.5 versus 11.5; P = 0.0001), attitudes towards people with AIDS (9.0 versus 6.7; P = 0.0008), subjective norms (45.5 versus 43.9; P = 0.011), and intention (1.3 versus 1.4; P = 0.020). No program effect was seen for attitudes towards sexual intercourse (47.0 versus 46.3, P = 0.44). CONCLUSIONS: These results indicate that it is feasible and effective to provide AIDS education for Tanzanian primary school children.

Acquired Immunodeficiency Syndrome↗
PubMed1994

Activation of human effector cells by different bacterial toxins (leukocidin, alveolysin, and erythrogenic toxin A): generation of interleukin-8.

We analyzed the transcription and release of interleukin-8 (IL-8) from human polymorphonuclear granulocytes (PMNs) and a lymphocyte-monocyte-basophil (LMB) cell population stimulated for different time periods (30 min to 16 h) with pore-forming bacterial toxins (Panton-Valentine leukocidin [Luk-PV] and alveolysin [Alv]) as well as with the erythrogenic toxin A (ETA) as a superantigen. At high toxin concentrations (500 ng/10(7) cells), Luk-PV and Alv led to a decreased IL-8 generation from LMBs within the first 30 min; with PMNs, a slight increase in IL-8 release was observed. Under these conditions, stimulation with ETA did not lead to an altered cellular IL-8 release. At lower concentrations (5 and 0.5 ng/10(7) cells), all three toxins led to a continuous increase (over 16 h) in IL-8 release and IL-8 mRNA expression of PMNs and LMBs. Preincubation of the cells with the protein tyrosine kinase inhibitors lavendustin A and tyrphostin 25 led to a reduction of the toxin-mediated effects on IL-8 release and IL-8 mRNA expression when Luk-PV and Alv were used as stimuli. In contrast, IL-8 synthesis in cells which were stimulated with ETA was not influenced by protein tyrosine kinase inhibition. From our data, one may suggest that multiple pathways for IL-8 production are operative in human leukocytes.

Bacterial Proteins↗
PubMed1993

[Antibiotic-induced diarrhea and pseudomembranous colitis].

Although not all antibiotic-induced diarrhoea is pseudomembranous, and not all pseudomembranous colitis is antibiotic-induced, by far the greater proportion of intestinal lesions and diarrhoea occurring in conjunction with Clostridium difficile infection are attributed to previous antibiotic treatment. The article consists in a review of pathogenic, diagnostic, treatment and nosocomial aspects.

Anti-Bacterial Agents↗
PubMed1992

Hypoglycemia presenting as basilar artery thrombosis.

BACKGROUND AND PURPOSE: Following our treatment of a patient with hypoglycemia-induced brain stem symptoms, we examined the possible mechanisms for hypoglycemia presenting as basilar artery disease. CASE DESCRIPTION: We describe a patient who had progressive brain stem symptoms due to a diet-induced hypoglycemia initially diagnosed as basilar artery thrombosis. Symptoms ceased immediately after intravenous glucose. CONCLUSIONS: Before invasive diagnostic and thrombolytic strategies are considered, hypoglycemia as a rare but important cause of acute brain stem dysfunction must be considered in patients suspected to suffer from basilar artery thrombosis.

Adult↗
PubMed1991

Some observations on the development of a 'scoring system' in an expert system for prediction of ovulation.

As part of the construction of an expert system for the diagnosis of infertility we have developed a scoring system for the identification of conditions which can interfere with ovulation. The scores were obtained from a group of clinicians, and the arithmetic means of these scores were used in the actual system. Correlation between the scores obtained from individual clinicians was very poor (r = 0.345 +/- 0.134). Correlation improved when groups of clinicians were compared. Thus scores derived from a group of clinicians will reflect more reliably the 'general medical opinion'. Scores derived from the opinion of clinicians should be regarded with caution until probabilities or weighting factors derived from real clinical data become available.

Expert Systems↗
PubMed1991

Degradation of 2-methylaniline and chlorinated isomers of 2-methylaniline by Rhodococcus rhodochrous strain CTM.

Rhodococcus rhodochrous strain CTM co-metabolized 2-methylaniline and some of its chlorinated isomers in the presence of ethanol as additional carbon source. Degradation of 2-methylaniline proceeded via 3-methylcatechol, which was metabolized mainly by meta-cleavage. In the case of 3-chloro-2-methylaniline, however, only a small proportion (about 10%) was subjected to meta-cleavage; the chlorinated meta-cleavage product was accumulated in the culture fluid as a dead-end metabolite. In contrast, 4-chloro-2-methylaniline was degraded via ortho-cleavage exclusively. Enzyme assays showed the presence of catechol 1,2-dioxygenase and catechol 2,3-dioxygenase as inducible enzymes in strain CTM. Extended cultivation of strain CTM with 2-methylaniline and 3-chloro-2-methylaniline yielded mutants, including R. rhodochrous strain CTM2, that had lost catechol 2,3-dioxygenase activity; these mutants degraded the aromatic amines exclusively via the ortho-cleavage pathway. DNA hybridization experiments using a gene probe revealed the loss of the catechol 2,3-dioxygenase gene from strain CTM2.

Aniline Compounds↗
PubMed1991

Degradation of 2-methylaniline in Rhodococcus rhodochrous: cloning and expression of two clustered catechol 2,3-dioxygenase genes from strain CTM.

Rhodococcus rhodochrous strain CTM degrades 2-methylaniline mainly via the meta-cleavage pathway. Conversion of the metabolite 3-methylcatechol was catalysed by an Mr 156,000 catechol 2,3-dioxygenase (C23OI) comprising four identical subunits of Mr 39,000. The corresponding gene was detected by using an oligonucleotide as a gene probe. This oligonucleotide was synthesized on the basis of a partial amino acid sequence obtained from the purified enzyme from R. rhodochrous. The structural gene of C23OI was located on a 3.5 kb BglII restriction fragment of plasmid pTC1. On the same restriction fragment the gene for a second catechol 2,3-dioxygenase, designated C23OII, was found. This gene coded for the synthesis of the Mr 40,000 polypeptide of the Mr 158,000 tetrameric C23OII. More precise mapping of the structural genes showed that the C23OI gene was located on a 1.2 kb BglII-SmaI fragment and the C23OII gene on the adjacent 1.15 kb SmaI fragment. Comprehensive substrate range analysis showed that C23OII accepted all the substrates that C23OI did, but additionally cleaved 2,3-dihydroxybiphenyl and catechols derived from phenylcarboxylic acids. C23OI exhibited highest activity towards methylcatechols, whereas C23OII cleaved unsubstituted catechol preferentially.

Aniline Compounds↗
PubMed1991

[Occlusion and dysfunction symptoms].

A sample of 81 students were examined for symptoms and signs associated with mandibular dysfunction. Women had a higher prevalence of these signs, which occurred statistically significant more frequently in subjects showing occlusal disturbances.

Adult↗
PubMed1990

Expert systems for the prediction of ovulation: comparison of an expert system shell (Expertech Xi Plus) with a program written in a traditional language (BASIC).

The use of an expert system shell (EXPERTECH Xi Plus) in the construction of an expert system for the diagnosis of infertility has been evaluated. A module was devised for predicting ovulation from the medical history alone. Two versions of this system were constructed, one using the expert system shell, and the other using QuickBASIC. The two systems have been compared with respect to: (1) ease of construction; (2) ease of knowledge base update; (3) help and explanation facilities; (4) diagnostic accuracy; (5) acceptability to patients and clinicians; (6) user-friendliness and ease of use; (7) use of memory space; and (8) run time. The responses of patients and clinicians were evaluated by questionnaires. The predictions made by the computer systems were compared to the conclusions reached by clinicians and to the "gold standard" of day 21 progesterone. The conclusions of this pilot study are: (1) the construction of this expert system was NOT facilitated by the use of this expert system shell; (2) update of the knowledge base was not facilitated either; (3) the expert system shell offered built-in help and explanation facilities, but as the system increased in complexity these became less useful; (4) after initial adjustment of decision thresholds the diagnostic accuracy of the system equalled that of the clinician; (5) the patient response to computer history-taking was very favorable but much less favorable to computer diagnosis; (6) the clinicians took a positive attitude to computer diagnosis; (7) the systems were easy to use; (8) the expert systems shell required much more memory space and had a much slower response time than the system written in BASIC.

Diagnosis, Computer-Assisted↗
PubMed1989

Roxithromycin in the treatment of pneumonia.

An open multicentre study of the efficacy and side effects of roxithromycin, a new macrolide antibiotic, in the treatment of community acquired pneumonia was undertaken. The diagnosis was verified by transtracheal aspiration. Fifty-three patients were studied. In the 49 patients evaluable the clinical efficacy rate was 92% (95% confidence limits 84-100%). Only by measurement of the fall in serum C-reactive protein was it possible to detect a difference in response between pneumonia due to Streptococcus pneumoniae and Haemophilus influenzae. The drug was well tolerated clinically and laboratory abnormalities included transient eosinophilia and elevated liver enzymes in two patients.

Adult↗
PubMed1987

Lucigenin-dependent chemiluminescence in mononuclear phagocytes. Role of superoxide anion.

A method for the measurement of reactive oxygen species generated by activated mononuclear phagocytes by use of lucigenin-dependent chemiluminescence was developed. Opsonized zymosan was used as a stimulant to evaluate the chemiluminescence response of monocytes. A cell-free system in which superoxide anion and hydrogen peroxide were produced by the xanthine-xanthine oxidase reaction was used to examine the role of these radical species in the excitation of lucigenin, and to standardize the chemiluminescence method. It was found that the light emission in lucigenin-dependent chemiluminescence was evoked by the superoxide anion, but other radicals may also be active.

Acridines↗
PubMed1986

In vitro locomotion of blood monocytes in millipore filters--evaluation of the leading front method.

Monocyte migration in millipore filters was measured by the leading front method. The precision, sensitivity and specificity of the method was assessed. The migrational response of monocytes to N-formylmethionylleucyl-phenylalanine (FMLP) was equal in concentrations ranging from 5 X 10(-9) to 5 X 10(-7) M. No dose-response relationship was demonstrated. The random analytical variation of the method was considerable, the mean coefficient of variation of duplicate experiments being 9.05%. The inter-subject variation was also large. A sample size of 30 to 40 individuals would be necessary to demonstrate a 1 SD difference between individuals at a significance level of 0.05 and power of 0.80. It is concluded that the method is able to detect agents which stimulate monocytes at least equally well as FMLP, but may be impracticable for demonstrating changes in monocyte migration, or differences in the migratory response among different populations of monocytes.

Cell Count↗