Comparison of office chairs with fixed forwards or backwards inclining, or tiltable seats

Three adjustments of an office chair seat: one inclining +10 degrees (forwards), one inclining -5 degrees (backwards), and one being freely tiltable from -8 degrees to +19.5 degrees were investigated using two groups of healthy female workers in a field (n = 12), and a laboratory study (n = 10), respectively. The seat adjustments were examined with regard to effects on foot swelling, lumbar muscular load, backrest pressure and subjective acceptability. Desk-work and typing were compared according to lumbar muscular activity, seat movements (tiltable seat), and backrest pressure. Foot swelling tended to increase with increasing seat height but was not influenced by the ability to tilt the seat or not. With the different seat adjustments lumbar muscular activity did not change systematically in spite of greater backrest pressure when the seat inclined backwards. The tiltable seat was preferred to the others. Typing was associated with a more constrained and tens posture than desk work, because movements, transferred to the tiltable seat, decreased and the muscular load increased. Backrest pressure was highest during typing. A tendency towards gradually increasing restlessness (i.e. seat movements) and increasing forward inclination of the tiltable seat with time was observed.     

Electron cytochemical demonstration of sulfhydryl groups in keratohyalin granules and in the peripheral envelope of cornified cells

Summary Although it is widely accepted that sulfhydryl and disulfide groups are important in keratinization, it has generally not proved possible to demonstrate these in the keratohyalin granules.A type of nuclear and cytoplasmic keratohyalin granule and the peripheral envelope adjacent to the plasma membrane in cornified cells show considerable Cytochemical similarity (Jessen, 1970). These sites have now been shown to react highly specifically with silver-methenamine. Blocking experiments indicate that sulfhydryl groups are responsible for this reaction.The findings in the present paper confirm the validity of the previous suggestion that there are several types of keratohyalin granules, of which one type is of widespread occurrence in keratinizing tissue and may be involved in the deposition of the peripheral envelope in cornified cells.The author wishes to thank Dr. H. Moe and Dr. D. P. Knight for valuable discussion. This work was supported by grants from The Danish Medical Research Council (512-149/69 and 512-1008/71) and The Danish Science Research Council (512-1009/71).     

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.     

Irradiated tumor cells adenovirally engineered to secrete granulocyte/macrophage-colony-stimulating factor establish antitumor immunity and eliminate pre-existing tumors in syngeneic mice

The specific aim of this study was to examine the prophylactic as well as the therapeutic efficacies of irradiated mouse CT26 colon cancer cells, infected with recombinant adenoviruses harboring cDNAs specific for granulocyte macrophage-colony-stimulating factor (GM-CSF), interferon (IFN-γ) and monocyte chemotactic protein1 (MCP-1). Results showed that tumor cells secrete the respective cytokines for several days after infection and subsequent irradiation. Vaccination with irradiated GM-CSF-secreting CT26 cells protected 90% of syngeneic mice challenged with live parental cells. On the other hand, vaccination with irradiated IFNγ or MCP-1-secreting CT26 cells totally failed to protect mice from tumor development after challenge with parental cells. None of the tumor-free mice initially vaccinated with irradiated GM-CSF-producing CT26 cells developed tumor upon repeated challenge with parental cells during the entire observation period. The establishment of specific and long-lasting antitumor immunity following vaccination with GM-CSF-producing tumor cells requires the simultaneous presence of GM-CSF and tumor antigen at the vaccine site. Depletion of CD8⁺ cells, but not CD4⁺ cells, blocked the vaccine efficacy of GM-CSF-producing tumor cells. Subcutaneous injection of irradiated GM-CSF-producing CT26 cells also effectively prevented the growth of a small load of parental tumor that was implanted 3 days earlier or the development of metastatic foci in the lung from intravenously injected parental cells either 7 days before or 3 days after vaccination. Our data thus show that, in these experimental tumor models, subcutaneous injection of irradiated tumor cells adenovirally, transduced with the GM-CSF gene leads not only to prevention of growth of subsequently implanted tumor but also to elimination of pre-existing and metastatic tumors.