Search PubMed⌕ Search

Biomedical subjects

E Larsson

Publications and source records attributed to E Larsson.

220 records · Page 13Linked to original sources

Significance of collateral arterial supply to Wilms' tumours.

The presence of collateral arterial supply was examined by angiography in 19 children with Wilms' tumour. Collateral arterial supply was related to tumour size. Ten of 14 tumours displaying collateral circulation were entirely intrarenal at operation, confirmed by histopathology. Angiography in Wilms' tumour is indicated when the results of urography, ultrasonography or computed tomography are equivocal or extrarenal tumour growth is suggested.

Adolescent↗

Expression of an interferon-gamma-like substance in normal and transplanted rat heart tissue.

The presence of interferon-gamma-like molecules has been reported not only in lymphocytes, but also in certain nerve cells and in normal skeletal muscle. We have studied the reactivity of the anti-interferon-gamma monoclonal antibody DB1 with frozen sections of normal and transplanted rat hearts. Cardiac grafts from PVG donor rats were transplanted to syngeneic PVG recipients or allogeneic Wistar/Kyoto recipient rats with the use of an accessory cervical heart transplantation technique. The allogeneic heart transplants were harvested 4 days and the syngeneic grafts 4 weeks after transplantation. In normal hearts there was a weak but distinct reactivity with the anti-interferon-gamma antibody in most muscle cells. In addition, some lymphocytes and the Purkinje fibers were positive. Hearts transplanted over an allogeneic barrier revealed that staining for interferon-gamma on muscle cells was substantially increased whereas no or only a moderate increase in the anti-interferon-gamma staining was seen in hearts transplanted to syngeneic recipients. These data indicate that interferon-gamma present in rat myocyte may be involved in the pathophysiology of graft rejection and also suggest that interferon-gamma may be of importance for the function of normal rat heart muscle cells.

Animals↗

Modulation of calcium signalling and proliferation in monoblastoid U-937 cells.

The effects of TPA (12-0-tetradecanoylphorbol-13-acetate) and G-protein modulators on the concentration of cytoplasmic Ca2+ ([Ca2+]i), cytoplasmic pH and cell growth were investigated in monoblastoid U-937 cells. The G-protein activator NaF causes a dose-dependent increase of [Ca2+]i, that is partially sensitive to inhibition by pertussis toxin. The [Ca2+]i rise appears to come mainly from extracellular sources, and the Ca2+ influx is mediated by channels insensitive to the Ca2+ blocker verapamil. The Ca2+ ionophore ionomycin causes a biphasic rise of [Ca2+]i, reaching steady state levels slightly higher than those attained with NaF. TPA per se has no effect on [Ca2+]i, but potently reverses the NaF or ionomycin induced [Ca2+]i rise. Also, TPA partially counteracted the acidification induced by NaF. Both NaF and ionomycin per se had no effect on cell growth but partially counteracted TPA induced growth inhibition. Interferon-gamma and tumor necrosis factor-alpha did not affect [Ca2+]i by themselves but lowered the [Ca2+]i of NaF stimulated cells. The cytokines had no effect on cytoplasmic pH. This study indicates that elevations of [Ca2+]i in themselves does not trigger proliferation, but alterations of [Ca2+]i modulates the regulation of U937-cell growth.

Calcium↗