Biomedical subjects

Jürgen Koehler

Publications and source records attributed to Jürgen Koehler.

3 recordsLinked to original sources

PubMed2006

Multiple sclerosis and the autonomic nervous system.

Symptoms related to alterations of the autonomic nervous system are frequent in patients with multiple sclerosis (MS). Bladder or bowel dysfunction or impairment of sexual performance is highly distressing for most MS patients,whereas the clinical relevance of other autonomic symptoms is less clear. Cardiovascular autonomic alterations might relate to clinical signs such as orthostatic intolerance; a relationship with fatigue is uncertain. However, the frequency of abnormal findings in tests for the cardiovascular autonomic system varies due to the lack of standardized test performance or differentially used cut-off values. The incidence of additional symptoms such as pupillomotor or sweating alterations and especially their relationship to overall autonomic nervous system abnormalities is not well known. Although their impact on daily life is low, they can at least serve as diagnostic tools. Beside these clinical aspects, alterations of the autonomic nervous system have also been reported to alter immunological cascades in experimental conditions. However, corresponding results have not been confirmed in clinical trials yet.

Autonomic Nervous System↗

PubMed2004

Kappa free light chains in cerebrospinal fluid as markers of intrathecal immunoglobulin synthesis.

BACKGROUND: Intrathecal immunoglobulin synthesis is observed in several inflammatory disorders of the central nervous system, but its detection by current laboratory tests is either tedious or relatively insensitive. We assessed the diagnostic accuracy of an assay for kappa free light chains (kappaFLC) in cerebrospinal fluid (CSF) and serum, and compared it with traditional tests for intrathecal immunoglobulin synthesis. METHODS: kappaFLCs were measured by nephelometry in CSF/serum pairs from 112 patients. Samples were excluded if blood contamination of CSF as a result of traumatic lumbar puncture (n = 12) or monoclonal bands in both CSF and serum (n = 5) were present. The remaining sample pairs were grouped according to the presence (n = 71) or absence (n = 24) of oligoclonal bands. Data were analyzed as kappaFLC concentrations in CSF, as kappaFLC CSF/serum ratios, and by use of the quotient diagram described previously for immunoglobulins. RESULTS: Both kappaFLC concentrations in CSF and the kappaFLC CSF/serum ratio identified patients with oligoclonal bands with high specificity and sensitivity. The areas under the ROC curves were 0.991 (95% confidence interval, 0.944-0.998) and 0.978 (0.924-0.996), respectively. Exclusion of patients with impaired blood-CSF barrier function further improved diagnostic accuracy. To account for patients with impaired blood-CSF barrier function, data were also analyzed in a quotient diagram. Only two patients without detectable oligoclonal bands would have been misclassified by this approach. CONCLUSIONS: Our data indicate that the nephelometric assay for kappaFLCs in CSF reliably detects intrathecal immunoglobulin synthesis. This automated and quantitative method could simplify the diagnostic procedure for CSF analysis in the routine laboratory.

Adolescent↗

PubMed2004

Masseter reflex in childhood and adolescence.

We report normative data of masseter reflex from a group of 54 children 2-16 years of age. For statistical analysis, the patients were divided into five age groups: 2-4, 5-7, 8-10, 11-13, and 14-16 years of age. A tap to the chin, using a hammer with a trigger device, elicited the masseter reflex. The response was recorded by surface electrodes. The onset latency and peak-to-peak amplitude of the averaged curve of eight reflex responses were measured. The reflex response could be recorded in all children and adolescents of all groups. The mean latency shortened from age 2 to 7 and was stable at the age of 8 years. As a sign of maturation, the increase of amplitude corresponded to the shortening of latency and was also stable at the age of 8 years. Abnormal side differences in latency of 0.9 ms (age group 2-4 years), 1.1 ms (age group 5-7 years), and 0.8 ms (age group 8-16 years) were evaluated. An amplitude ratio (lower amplitude divided by higher one) above 0.33 was calculated as normal.

Adolescent↗