No evidence for brain stem cooling during face fanning in humans.

The interpeak latencies (IPLs) of the acoustically evoked brain stem potentials depend on brain stem temperature. This was used to see whether face fanning during hyperthermia lowers brain stem temperature. In 15 subjects, three thermally stable conditions were maintained by a water bath. In each condition the IPLs were determined in 10 separate trials. In condition A esophageal temperature (Tes) was 36.9 +/- 0.3 degrees C and increased to 38.6 +/- 0.2 degrees C in condition B. In conditions A and B the head was enclosed in a ventilated hood (air temperature 38 degrees C, relative humidity 100%) to suppress any direct heat loss from the head. From conditions A to B the IPL at peaks I-V decreased by 0.146 ms/degrees C change in Tes, reflecting a change in brain stem temperature. In condition C the hood was removed and the face was fanned by a cold air-stream (8-15 degrees C, 4-10 m/s) to maximize direct heat loss from the head. Skin temperature at the sweating forehead decreased from 38 to 23 degrees C, whereas Tes in condition C was maintained at the same level as in condition B (38.5 +/- 0.2 degrees C). The IPL at peaks I-V showed no difference between conditions B and C. It is concluded that face fanning in hyperthermic subjects does not dissociate brain stem temperature from Tes.     

Non-cutaneous peripheral thermosensitivity in the goat (Capra hircus)

1. A 0.2 m2 area of the trunk skin was denervated and its center was externally cooled or warmed, when central body temperature was lowered. 2. When the denervated skin was cooled, the central body temperature, at which shivering occurred, was significantly higher than with warming of the denervated skin. 3. It is concluded that the difference was caused by temperature signals originating from thermoreceptors in tissue layers underneath the denervated skin.     

Absolute β-catenin concentrations in Wnt pathway-stimulated and non-stimulated cells

The intracellular level of the proto-oncoprotein β-catenin is a parameter for the activity of the Wnt pathway, which has been linked to carcinogenesis. The paper introduces a novel sandwich-based ELISA for the determination of the β-catenin concentration in lysates from cells or tissues. The advantages of the method were proven by determining β-catenin levels in cell lines and in cells after activation of the Wnt pathway. Analysis revealed high β-catenin concentrations in the cell lines HeLa, KB, HT1080, MCF-7, U-87 and U-373, which had not been described before. β-Catenin concentrations were compared in HEK293 and C57MG cells after activation of the Wnt pathway. The β-catenin concentrations increased by different factors depending on whether the Wnt pathway was activated by incubation with LiCl or with Wnt-3a-conditioned medium. This finding indicated that the β-catenin level depends on the way and level of Wnt pathway activation. The quantitative analysis of β-catenin in colorectal tumours revealed high β-catenin levels in tumours with truncating mutations in the APC gene.