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G Knudsen

Publications and source records attributed to G Knudsen.

9 recordsLinked to original sources
PubMed2000

GATA-1- and FOG-dependent activation of megakaryocytic alpha IIB gene expression.

FOG is a multitype zinc finger protein that is essential for megakaryopoiesis, binds to the amino-terminal finger of GATA-1, and modulates the transcription of GATA-1 target genes. Presently investigated are effects of FOG and GATA-1 on the transcription of the megakaryocytic integrin gene, alpha IIb. In GATA-1-deficient FDCER cells (in the presence of endogenous FOG), ectopically expressed GATA-1 activated transcription 3-10-fold both from alpha IIb templates and the endogenous alpha IIb gene. The increased expression of FOG increased reporter construct transcription 30-fold overall. Unexpectedly, alphaIIb gene transcription also was stimulated efficiently upon the ectopic expression in of FOG per se. This occurred in the absence of any detectable expression of GATA-1 and was observed in multiple independent sublines for both the endogenous alpha IIb gene and transfected constructs yet proved to depend largely upon conserved GATA elements 457 and 55 base pairs upstream from the transcriptional start site. In 293 cells, FOG plus GATA-1 but not FOG alone only moderately stimulated alpha IIb transcription, and no direct interactions of FOG with the alpha IIb promoter were detectable. Thus, FOG acts in concert with GATA-1 to stimulate alpha IIb expression but also can act via a GATA-1-independent route, which is proposed to involve additional hematopoietic-restricted cofactors (possibly GATA-2).

Base Sequence↗
PubMed1995

Prophylaxis of venographically diagnosed deep vein thrombosis in gastrointestinal surgery. Multicentre trials 20 mg and 40 mg enoxaparin versus dextran.

OBJECTIVE: To compare enoxaparin and dextran 70 for the prophylaxis of venographically diagnosed deep vein thrombosis (DVT) after gastrointestinal operations. DESIGN: Part 1: randomised double blind trial; Part 2: single blind study with historical controls. SETTING: Eight Norwegian hospitals. SUBJECTS: 381 Patients undergoing elective gastrointestinal operations. INTERVENTIONS: Part 1 (n = 329): enoxaparin 20 mg subcutaneously starting two hours before operation and continuing until the patient was fully mobilised or had had 10 injections and a placebo infusion of 0.9% sodium chloride, or dextran 70,500 ml at the start of the operation, on the evening of operation, and on the first, third, and fifth postoperative days and placebo subcutaneous injections. Part 2 (n = 52): enoxaparin 40 mg in the same regimen as part 1 (compared with 39 historical controls). Venograms 4-6 days post-operatively. MAIN OUTCOME MEASURE: Venographically confirmed DVT. RESULTS: Part 1: Because of the high overall incidence of DVT an interim analysis was done which showed 33/101 DVT (33%) among high risk patients in the enoxaparin 20 mg group and 33/107 (31%) in the dextran 70 group. The corresponding figures for patients at medium risk were 2/27 (7%) for enoxaparin 20 mg and 5/27 (19%) for dextran 70 (95% confidence interval (CI) for the difference--11.9 to 9.8). Part 2: the dose of enoxaparin was therefore increased to 40 mg and prophylaxis restricted to patients with cancer. There were 6/49 DVT (12%), which was compared with a random sample from the dextran 70 group from part 1 (historical controls) in which the incidence was 15/39 (38%, 95% CI of the difference 4.0 to 8.4). There were no pulmonary emboli, only 4 thrombi were above the knee and there were 4, 1 and 3 clinical DVT in the 20 mg and 40 mg enoxaparin, and dextran 70 groups, respectively. CONCLUSIONS: Enoxaparin 20 mg and dextran 70 are effective prophylaxis for patients at medium risk, but enoxaparin 40 mg is required for those at high risk.

Adult↗
PubMed1992

Development of a gene transfer system for curing of plasmids in the marine fish pathogen Vibrio salmonicida.

All reported natural isolates of the marine fish pathogen Vibrio salmonicida contain plasmids, and in another marine fish pathogen, Vibrio anguillarum, it has been shown that a plasmid is important for expression of virulence by the organism. To study the function of the plasmids in V. salmonicida, we developed a gene transfer system based on the plasmid RSF1010 replicon. The gene transfer system was used to construct a plasmid-free strain, and this strain was found to behave similarly to the wild type in a fish pathogenicity test based on intraperitoneal injection of the bacteria. We were unable to detect any other phenotypic differences between the two strains. It could therefore be concluded that at least in the V. salmonicida strain tested, extrachromosomal DNA is not required for expression of virulence.

Animals↗
PubMed1989

The non-linear relationship between nerve conduction velocity and skin temperature.

Median motor and sensory nerves were examined in 20 healthy subjects. Superficial stimulating and recording electrodes were used, and the nerves were examined at natural skin temperature, after cooling and after heating of the arm. The conduction velocity for the fastest and slow conducting sensory fibres (temperature range 17-37 degrees C), and for the fastest conducting motor fibres (temperature range 19-38 degrees C) increased non-linearly with increase in skin temperature. Similarly, distal motor latencies increased non-linearly with decrease in skin temperature. The effect of temperature was most pronounced in the low temperature range, and change in conduction velocity per degree centigrade was reduced toward higher skin temperature. Sensory nerve response duration increased linearly with decline in skin temperature. Sensory and motor amplitude did not show any significant relation to skin temperature.

Adult↗
PubMed1989

Nerve conduction velocity in man during deep diving to 360 msw.

The function of the sensory and motor median nerves was examined in 6 divers during a simulated dive to 360 meters of seawater (msw), with a mixture of helium and oxygen (heliox) as breathing gas. Divers were examined in the compression chamber before the dive, at 360, 300, 240, 130, 50, and 5 msw, and with skin temperatures ranging from 29.2 degrees to 35.2 degrees C. Examinations were performed with superficial stimulating and recording electrodes. Fast sensory nerve conduction decreased with increase in hyperbaric pressure and with decrease in skin temperature. There was no significant correlation between slow sensory conduction and hyperbaric pressure. Distal motor latency increased with increase in hyperbaric pressure and with decrease in skin temperature. The effect of pressure was independent of temperature. No significant functional changes were detected in the main nerve trunk proximal to the wrist or in the F-wave responses.

Adult↗
PubMed1988

A Danish randomized trial comparing breast-preserving therapy with mastectomy in mammary carcinoma. Preliminary results.

The present study comprises 847 women operated upon for invasive breast carcinoma at 19 surgical departments and enrolled in protocol DBCG-82TM from January 1983 to November 1987. Among them 662 (78%) were allocated for breast-preserving therapy or mastectomy by randomization, while 185 patients (22%) did not accept randomization. Within the randomized group 6% could not be entered into adjuvant protocols, i.e. subsequent programmes of postoperative therapy and follow-up. This left 619 evaluable patients. In the non-randomized series 26% did not fulfil the demands for entrance into the adjuvant protocols, leaving 136 evaluable patients, 60 of whom had chosen a breast-preserving operation and 76 mastectomy. In the randomized series the patients in the two treatment arms were comparable in age, menopausal status, site of tumour, pathoanatomical diameter of the tumour, number of removed axillary lymph nodes, number of metastatic axillary lymph nodes, and distribution on adjuvant regimens. Ninety per cent of the patients in the randomized group accepted the method offered, whereas 10% declined and wanted the alternate form of operation. The median follow-up period was approximately 1.75 years. The cumulative recurrence rate in the randomized group was 13% and in the non-randomized group 7%. These results are preliminary. Life-table analyses have not so far demonstrated differences in recurrence-free survival either in the randomized or the non-randomized series.

Adult↗
PubMed1983

Observer variability of and comparison between visual and central bearing point methods of evaluating denture occlusion.

Central bearing point and visual methods were used in the study of repeated recordings of occlusion in 30 patients with old complete dentures. The results were classified into di- and trichotomous categories. Intra- and interexaminer variability were generally high. In addition, significant differences were found between the examiners in the level of recording denture occlusion. The use of trichotomous categories increased the variability to an unacceptable level. The variability with the central bearing point method was higher than with the visual method. However, occlusal discrepancies were found with significantly higher frequencies with the central bearing point method than with the visual method.

Aged↗