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Kristian Bartnes

Publications and source records attributed to Kristian Bartnes.

7 recordsLinked to original sources
PubMed2006

[When should the trauma team be activated?].

BACKGROUND: On admission to hospital, severely injured patients should be received by a trauma team so that the prospects of early life-saving treatment are not precluded. Considerations about use of resources indicate that the team is not activated when the likelihood of serious injury is low. A recommendation with criteria for activation of the trauma team has been established at the University Hospital of North Norway. We have studied how the recommendations were followed and calculated over- and under-triage and to highlight the question of whether activation should rather be automatically implemented based on predefined criteria. MATERIAL AND METHODS: We use descriptive statistics to analyse compliance with the recommendation as well as pre- and intra-hospital data for trauma patients who prior to admission were recognised as having fulfilled the criteria. RESULTS: Of the 109 trauma victims who, according to the recommendation, from 1 June 2001 to 31 May 2002 should have been received by the trauma team, 59 were received by a surgeon alone. Given that all patients with an injury severity score of 16 or more should be received by a trauma team, under-utilisation of the team was 50%, whereas the proportion of excess calls was 58%. Elimination of under-utilisation among this group of patients would, by strict adherence to the criteria, have conferred a very modest increase in the proportion of superfluous calls to 61%. INTERPRETATION: The trauma team should be activated automatically in accordance with predefined criteria.

Adolescent↗
PubMed2006

Coronary bypass graft patency cannot be determined by multidetector spiral computed tomography.

OBJECTIVES: Angiography by selective catheterization is the reference standard for coronary bypass graft patency assessment but carries a risk of serious complications. We have investigated whether 16-slice multidetector spiral computed tomography (MDCT) can substitute for selective angiography. DESIGN: Two to three years after coronary artery bypass grafting, 45 patients with a total of 156 bypasses (100 single and 28 sequential grafts) were examined with both MDCT and conventional selective angiography on the same day. The bypasses were classified as patent, stenotic or occluded. RESULTS: The likelihood ratio for MDCT-detected occlusion was 40, reflecting a fairly high combined sensitivity and specificity. However, 24% of the distal anastomoses could not be evaluated by MDCT, mainly because of respiratory movements, artifacts due to metal clips, and small vessel dimensions. Moreover, seven out of 117 bypasses (6%) deemed evaluable by MDCT were wrongly classified by this method. CONCLUSIONS: At present, 16-slice MDCT cannot replace selective angiography for assessment of coronary bypass graft patency since 24% of bypasses could not be evaluated by this method, and an error rate of 6% is unacceptable.

Adult↗
PubMed2003

Spontaneously formed tumorigenic hybrids of Meth A sarcoma cells and macrophages in vivo.

We have recently demonstrated that malignant cells can hybridize with tissue macrophages in vitro, giving rise to tumorigenic hybrids. We now demonstrate that this can occur spontaneously in vivo as a result of fusion between inoculated Meth A sarcoma cells and host cells, presumably macrophages. Thus, from tumor cell suspensions prepared by collagenase perfusion and density centrifugation, hybrid cells could be isolated that were neoplastic but in contrast to Meth A expressed macrophage markers and had phagocytic capacity. Their morphologic features were intermediate between Meth A and macrophages. By taking advantage of a semiallogeneic experimental system by inoculation of Meth A cells from BALB/c (H-2 K(d)) into (BALB.K x BALB/c) F(1) (H-2(k/d)), hybrid cells from these tumors could be shown to express MHC antigens of both the Meth A and the host haplotypes. Hybrid cells grew faster than Meth A cells in vivo, indicating acquisition of growth-promoting properties through heterotypic cell fusion.

Animals↗
PubMed2002

Spontaneously formed tumorigenic hybrids of Meth A sarcoma and macrophages grow faster and are better vascularized than the parental tumor.

Macrophages and Meth A sarcoma cells spontaneously fuse and give rise to tumorigenic hybrid cell lines with a mixed phenotype. We report here that the hybrid tumors grow faster and have a strikingly better developed vasculature than the parent sarcoma. Thus, electron microscopy and immunohistochemical analysis revealed that in the most active areas of neovascularization, the tumors that emerged from inocula of monoclonal hybrid cell populations had a microvessel density nearly twice that of Meth A tumors after 1 week of growth. Moreover, the proportion of vessels associated with pericytes, detected by staining for smooth muscle alpha-actin, was 3 times higher in the hybrid tumors, attesting to the more advanced differentiation of their vasculature. The collagenous stroma component was also more extensive in the hybrid tumors. Concentration of the angiogenic proteins vascular endothelial growth factor (VEGF) and transforming growth factor-beta (TGF-beta) were significantly higher in supernatants of hybrid cell cultures compared with Meth A cultures. These observations indicate that the growth advantage of the hybrid tumors over the parental sarcoma is due to a higher angiogenic capacity. Because the malignant features of many tumors correlate with angiogenesis and because macrophages are known to be major producers of angiogenic factors, our data open the possibility that the intense neovascularization of highly aggressive cancers in some cases reflects the acquisition of macrophage traits by heterotypic cell fusion.

Animals↗
PubMed2002

Spontaneous hybridization of macrophages and Meth A sarcoma cells.

We present evidence of hybridization between Meth A sarcoma cells and syngeneic as well as semigeneic peritoneal macrophages. The resultant hybrids are characterized by morphology, membrane markers, ploidy, chromosomal content and functional features. Briefly, after a few days of coculture, cells appeared with morphology intermediate between the 2 original cell types. Typical macrophage surface molecules appeared in the hybrids. Meth A cells were labeled with red fluorescence and macrophages with green fluorescence. After 4 days in vitro, hybrids with yellow fluorescence appeared. Macrophages from BALB.K mice (H-2 K(k)) were cocultivated with Meth A cells from BALB/c mice (H-2 K(d)). The semigeneic hybrids displayed both specificities, as demonstrated by flow cytometry. The hybrids appeared moderately phagocytic, less so than the macrophages and markedly more so than the essentially nonphagocytic Meth A cells. The hybrids had a mean number of 76 chromosomes, as opposed to 53 in the Meth A cells and 40 in the macrophages. The macrophage DNA index was set at 1; Meth A cells were found to have an index of 1.6 in G1 phase, and the hybrids had a 2.6 index. The hybrids grew more slowly in vitro than Meth A cells, but grew faster in vivo.

Aneuploidy↗
PubMed2002

[Long-term results with the left internal mammary artery as coronary bypass].

BACKGROUND: From 1986 we have routinely used the left internal mammary artery instead of autologous vein as bypass to the left anterior descending coronary artery. MATERIAL AND METHODS: A cohort of 52 patients has been followed up for up to 12 years. Six years postoperatively, 40 patients were evaluated by clinical examination, exercise testing and serum lipid assessment. Of these, 38 underwent angiography of the native coronary arteries and of all grafts, which represented 47 left internal mammary artery, 90 saphenous vein, and 3 right internal mammary artery bypasses. Information regarding angina recurrence and the need for repeated revascularisation was obtained from hospital records. Twelve-year mortality data were provided by public registers. RESULTS: Fifty patients were discharged alive. Two serious complications, of which one was fatal, were directly related to the use of the left internal mammary artery. After six years, all the re-examined patients had improved their exercise tolerance; 25 (63%) were angina-free. 44 (94%) left internal mammary artery and 67 (74%) saphenous vein bypasses were patent. Tobacco consumption was considerably reduced over the first six years postoperatively while mean triglyceride and cholesterol levels remained moderately elevated. After 12 years, 18 patients were deceased, half of them from coronary heart disease. INTERPRETATION: Our results are in accordance with large, international studies.

Adult↗