Machine-learned analysis of quantitative sensory testing responses to noxious cold stimulation in healthy subjects.

BACKGROUND: Pain in response to noxious cold has a complex molecular background probably involving several types of sensors. A recent observation has been the multimodal distribution of human cold pain thresholds. This study aimed at analysing reproducibility and stability of this observation and further exploration of data patterns supporting a complex background. METHOD: Pain thresholds to noxious cold stimuli (range 32-0 °C, tonic: temperature decrease -1 °C/s, phasic: temperature decrease -8 °C/s) were acquired in 148 healthy volunteers. The probability density distribution was analysed using machine-learning derived methods implemented as Gaussian mixture modeling (GMM), emergent self-organizing maps and self-organizing swarms of data agents. RESULTS: The probability density function of pain responses was trimodal (mean thresholds at 25.9, 18.4 and 8.0 °C for tonic and 24.5, 18.1 and 7.5 °C for phasic stimuli). Subjects' association with Gaussian modes was consistent between both types of stimuli (weighted Cohen's κ = 0.91). Patterns emerging in self-organizing neuronal maps and swarms could be associated with different trends towards decreasing cold pain sensitivity in different Gaussian modes. On self-organizing maps, the third Gaussian mode emerged as particularly distinct. CONCLUSION: Thresholds at, roughly, 25 and 18 °C agree with known working temperatures of TRPM8 and TRPA1 ion channels, respectively, and hint at relative local dominance of either channel in respective subjects. Data patterns suggest involvement of further distinct mechanisms in cold pain perception at lower temperatures. Findings support data science approaches to identify biologically plausible hints at complex molecular mechanisms underlying human pain phenotypes. SIGNIFICANCE: Sensitivity to pain is heterogeneous. Data-driven computational research approaches allow the identification of subgroups of subjects with a distinct pattern of sensitivity to cold stimuli. The subgroups are reproducible with different types of noxious cold stimuli. Subgroups show pattern that hints at distinct and inter-individually different types of the underlying molecular background.

Superior mesenteric artery syndrome in traumatic brain injury: two cases.

One of the many causes of enteral feeding (EF) intolerance after traumatic brain injury (TBI) is superior mesenteric artery syndrome (SMAS). Although it is reported in pediatric brain injury, few cases are noted in adults. To increase awareness of this medically treatable condition, we present two patients who developed SMAS after sustaining severe brain injury. SMAS results from compression of the duodenum by the SMA against the aorta and risk factors include acute weight loss, prolonged recumbency, and spasticity--all frequently encountered in severe TBI. After gastric decompression, symptoms often resolve with weight gain achieved by conservative treatment; including feeding in the left lateral or prone position, hyperalimentation, or extension of a feeding tube beyond the obstruction. SMAS should be considered in the presence of EF intolerance in severe adult TBI because multiple risk factors may be present.

[Vocational education of the handicapped in the European Community--experiences from the network of vocational rehabilitation services]. / Berufliche Bildung Behinderter in der EG--Erfahrungen aus dem Netzwerk der beruflichen Rehabilitationseinrichtungen.

Organized cooperation in the field of vocational rehabilitation has been established at EC-level more than fifteen years ago, the first meeting of the community network of rehabilitation centres having taken place on the 20th of October, 1975. This cooperation has been intensified and extended by HELIOS, the second action programme on behalf of disabled persons adopted by the Council of Ministers in April 1988, to continue the efforts started by the initial action programme. In the fields of occupational qualification, languages, and new technologies, "Europe 92" will give rise to new challenges that imperatively ask for closer cooperation among rehabilitation workers in the Community. In the framework of HELIOS, this cooperation has already been started.

[Occupational rehabilitation yesterday, today and tomorrow as exemplified by the vocational retraining centers]. / Berufliche Rehabilitation gestern, heute und morgen am Beispiel der Berufsförderungswerke.

Developed in the 1960s, the concept for vocational rehabilitation in the vocational retraining centres has proven its worth also in the face of the great challenges of the 80s. Not all of the partly profound changes which have taken place in the environs of vocational rehabilitation over the last few years had been positive ones. Before this background, it must therefore be asked how the standard attained by the vocational retraining centres is to be viewed and which route the vocational rehabilitation field is going to take in the 90s. The process of societal and technological change over recent years is likely to further accelerate in the 90s, with numerous implications for vocational education and disability policies. Even more so than in the past, this process will require adjustments to be made, but equally give rise to innovative efforts and developments. The demands to be faced by the facilities are therefore going to increase, and major re-structuring processes will have to take place also in the vocational retraining centres.