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S Johansen

Publications and source records attributed to S Johansen.

At least 73 records · Page 4Linked to original sources
PubMed1990

Organization of the mitochondrial genome of Atlantic cod, Gadus morhua.

The mitochondrial DNA (mtDNA) from the Atlantic cod, Gadus morhua, was mapped using 11 different restriction enzymes and cloned into plasmid vectors. Sequence data obtained from more than 10 kilobases of cod mtDNA show that the genome organization, genetic code, and the overall codon usage have been conserved throughout the evolution of vertebrates. Comparison of the derived amino acid sequences of proteins encoded by cod mtDNA to the ones encoded by Xenopus laevis mtDNA revealed that the amino acid identity range from 46% to 93% for the different proteins. ND4L is most divergent while COI is most conserved. GUG was found as the translation initiation codon of the COI gene, indicating a dual coding function for this codon. The sequences of the 997 base pair displacement-loop (D-loop)-containing region and the origin of L-strand replication (oriL), are presented. Only few of the primary and secondary structure features found to be conserved among mammalian mitochondrial D-loops, can be identified in cod. Presence of CSB-2 in the D-loop-containing region and the conserved hairpin structure at oriL, indicates that replication of bony fish mtDNA may follow the same general scheme as described for higher vertebrates.

Amino Acid Sequence↗
PubMed1990

Galactose removal kinetics during hypoxia in perfused pig liver: reduction of Vmax, but not of intrinsic clearance Vmax/Km.

The galactose elimination kinetics was examined in five perfused pig livers of 1.2 kg during hypoxia induced by administration of 2, 4 or 7% oxygen in the oxygenator instead of 20% as used in nine control experiments, previously published. Galactose was given as four to five successive constant infusion rates so that successive steady-state period with galactose concentrations from 0.04 to 5 mmol l-1 were obtained in each experiment. From the relationship between the calculated elimination rate and the perfusate galactose concentration, values of the maximal elimination rate Vmax and the half saturation concentration Km were calculated. Both Vmax and Km were reduced by hypoxia: the lower the oxygen supply, the greater the reduction. Vmax was about 0.08 mmol min-1 kg-1 liver at 2% oxygen and about 0.18 mmol min-1 kg-1 liver at 4-7% oxygen; both being significantly lower than the value of 0.43 mmol min-1 kg-1 liver at 20% oxygen. Km was about 0.07 mmol l-1 at 2% oxygen and 0.13 mmol l-1 at 7% oxygen; both significantly lower than the value of 0.23 mmol l-1 at 20% oxygen. A nearly parallel reduction of liver ATP concentration and galactose Vmax indicates that the galactose Vmax may reflect the phosphorylation capacity of the liver cells. The Vmax/Km ratio (intrinsic hepatic clearance) was unchanged during hypoxia.

Animals↗
PubMed1989

[Alpha 1-antitrypsin deficiency and emphysema. Replacement therapy?].

We present three patients with homozygous alpha-1-antitrypsin deficiency and pulmonary emphysema. They demonstrate the typical patterns of this syndrome: panlobular emphysema, early age of onset, serum alpha-1-antitrypsin below 35% of normal and phenotype PiZZ. We discuss epidemiology, pathogenesis and clinical manifestations, and review the experience concerning replacement therapy using alpha-1-antitrypsin derived from human plasma. We strongly point out the importance of stopping cigarette smoking in such patients.

Adolescent↗
PubMed1989

Formation of chlorinated PAH--a possible health hazard from water chlorination.

Four PAH compounds, fluorene, anthracene, fluoranthene and benzo(a)pyrene were dissolved in humus poor (lake) and humus rich water. The samples were chlorinated, stored for three days, and extracted with cyclohexane. Chlorinated derivatives of the four compounds were synthesised and used as calibration standards for quantitative analysis of the corresponding chlorinated PAH formed during the experiment. The synthesized chlorinated PAH were tested for mutagenic activity by the Ames test, and their octanol/water partition coefficient (Pow) were determined by thin layer chromatography. Chlorinated fluorene, fluoranthene and benzo(a)pyrene were formed during chlorination of PAH polluted lake water, but not during chlorination of the humus rich water samples. All chlorinated PAH except 9,10-dichloroanthracene, acted as strong mutagens both in the presence and in the absence of metabolic activation, while benzo(a)pyrene was the only mutagen active parent PAH. The determined Pow showed high lipophilicity for all chlorinated PAH. Theoretically determined bioconcentration factors (BCF) were found to be extremely high, and increased with increasing ring number and increasing number of chlorine atoms attached to the ring.

Anthracenes↗
PubMed1988

A model for forecasting intermittent skilled home nursing needs.

The problem of forecasting the need and the cost for post-discharge skilled home nursing services is addressed by a simple statistical model. The model, assumptions, and simple calculations are described. Use of the model is illustrated with 7598 cancer patients and 2337 myocardial infarction patients. Simulation of the impact of changes in the health care delivery system toward greater and lesser severity of hospitalized patients is carried out. Two key projections illustrating the model's output are the number of patients with these diseases who will need care and the cost of that care.

Costs and Cost Analysis↗
PubMed1988

Nucleotide sequence of the Physarum polycephalum small subunit ribosomal RNA as inferred from the gene sequence: secondary structure and evolutionary implications.

The nucleotide sequence of the Physarum polycephalum small subunit ribosomal RNA (SSU rRNA) gene has been determined. Sequence data indicate that the mature 19S SSU rRNA is 1,964 nucleotides long. A complete secondary structure model for P. polycephalum SSU rRNA has been constructed on the basis of the Escherichia coli 16S rRNA model and data from comparative analyses of 28 different eukaryotic sequences. A "four-helix" model is presented for the central domain variable region. This model can be applied both to vertebrate and most lower eukaryotic SSU rRNAs. The increased size of P. polycephalum SSU rRNA relative to the smaller SSU rRNAs from such other lower eukaryotes, as Dictyostelium, Tetrahymena or Saccharomyces is due mainly to three G+C-rich insertions found in two regions known to be of variable length in eukaryotes. In a phylogenetic tree constructed from pairwise comparisons of eukaryotic SSU rRNA sequences, the acellular myxomycete P. polycephalum is seen to diverge before the appearance of the cellular myxomycete Dictyostelium discoideum.

Base Sequence↗
PubMed1986

Coronary artery thrombosis and elevated urine immunoreactive thromboxane B2.

Immunoreactive thromboxane B2 (i-TXB2) was measured by radio-immunoassay (RIA) in urines collected over eight hours on the day of admission in 25 patients who were admitted with the diagnosis of myocardial infarction. In 16 of the patients myocardial infarction was confirmed by ECG and plasma enzymes. Another patient presented with pulmonary embolism and the remaining eight patients had angina pectoris. A further eight hour urine collection was obtained 24 hours later from eleven of the sixteen patients with myocardial infarction. In these eleven patients myocardial infarction was associated with five fold higher urine i-TXB2 (2.72 +/- 0.48 ng/ml) at the day of admission when compared to patients admitted under the same diagnosis but found to have angina only (0.51 +/- 0.08 ng/ml, p less than 0.001). In patients with myocardial infarction the urine i-TXB2 values were reduced 24 hours later (1.58 +/- 0.27 ng/ml, p less than 0.01). One patient was followed with urine i-TXB2 from three days prior to diagnosis of myocardial infarction and to one day prior to a second infarction. In this patient i-TXB2 was highest three days prior to infarction. We conclude that this early elevation of urine i-TXB2 three days prior to diagnosis of infarction and the increased i-TXB2 in patients with myocardial infarction when compared to patients with angina suggest thromboxane is probably released from activated platelets prior to infarction. We suggest that urine i-TXB2 may be of value in the differential diagnosis between myocardial infarction and angina.

Aged↗
PubMed1986

Pharmacokinetics of ciprofloxacin and effect of repeated dosage on salivary and fecal microflora.

The pharmacokinetics of ciprofloxacin was studied in 12 volunteers during a 5-day course of 500 mg of ciprofloxacin given orally twice a day. The effects on the microflora of saliva and feces were also examined. Serum and urine samples were assayed for ciprofloxacin microbiologically, and the salivary and fecal microflora were examined quantitatively after processing onto a series of selective media. Fecal samples were also investigated for the presence of Clostridium difficile and its cytotoxin. The MICs for new colonizing bacteria were examined in the salivary and fecal samples. There was no accumulation during the course of 5 days with peak serum concentrations identical (2.8 and 2.3 mg/liter) after the first and final doses, and the areas under the serum curves were similar (9.6 mg/liter). The serum half-life was 2.5 h on both days. The changes in the salivary flora were minor and affected only the neisseriae. In the fecal flora, the numbers of enterobacteria and enterococci decreased markedly, whereas the changes in anaerobic flora (anaerobic cocci, fusobacteria, and bacteroids) were not so pronounced. However, 14 days after the drug was discontinued, the salivary and fecal flora were normalized in all respects. No new colonization of ciprofloxacin-resistant bacteria for which MICs were above 1.0 mg/liter was observed. C. difficile or its cytotoxin was not detected.

Adult↗
PubMed1986

Comparison of two prospective rate-setting models: the DRG and PIR models.

The article compares two statistical prospective hospital reimbursement models: the diagnosis-related group (DRG) model and the prospective individualized reimbursement (PIR) model. Both models are applied to the same variables from the same data set, a random sample of 10,000 hospital discharges in Maryland in 1983. For comparative purposes, the two statistical models are allowed to differ only in their treatment of the predictive variable, "patient age." The criteria of comparison and results (DRG and PIR, respectively) are: number of patient groups required (469 and 337); accuracy of prediction of length of stay (38 percent and 45 percent of the total variation is explained by the models); correction for sampling bias (0 and 2.4 percent additional explained variation); and accuracy of prediction of total charges ($526 and $262 average error per patient).

Adolescent↗
PubMed1985

Pulmonary ventilation in long-term beta-adrenergic blockade after myocardial infarction.

In a double-blind, randomized study, the long-term effects of timolol and placebo on FEV1, PEFR, FVC, VC, respiratory rate and heart rate were compared in 32 patients surviving acute myocardial infarction, 17 on timolol and 15 on placebo. The patients were assessed before and after 1, 3 and 6 months of medication, and then every 6 months for up to 2 years; the mean observation period was 17.4 months. Timolol decreased FEV1 significantly (9-17%) throughout the study. PEFR and FVC fell by 4-13% and 9-11%, respectively, on timolol; the reductions were significant at 3, 6 and 24 months, and at 1, 3 and 6 months, respectively. VC showed only small changes and respiratory rate did not change. In only one patient were the changes in pulmonary function of clinical relevance. Thus, significant, persisting airways dysfunction was induced by long-term beta-adrenergic blockade in patients surviving myocardial infarction.

Adrenergic beta-Antagonists↗
PubMed1985

Turnover rate of interstitial albumin in rat skin and skeletal muscle. Effects of limb movements and motor activity.

Fractional removal rate (FRR) of radioactive-labelled human serum albumin (I-HSA) injected subcutaneously or intramuscularly was determined by external gamma-detecting equipment. Radioactivity over the injection site fell monoexponentially during registration periods up to 6 h. The FRR was calculated as the turnover rate constant of the radioactivity removal. The FRR fell into one of two ranges: in anaesthetized rats FRR was 0.02-0.03 h-1, and in awake and freely moving rats FRR was 0.08-0.11 h-1. In awake rats, FRR was similar during day and night (spontaneous motor activity is four times higher during the night). Passive limb movements at 1 Hz in anaesthesia increased FRR in skin to that in awake rats, while FRR in skeletal muscle was unchanged. Immobilization resulted in FRR similar to that in anaesthesia. Interstitial albumin mass did not change during 6 h of anaesthesia. It is concluded that the observed FRR reflects steady state changes in albumin turnover. In the awake and freely moving rats at least 3/4 of the removal of albumin is by the lymphatics. Calculated lymph flow was 10 microliters g-1 h-1 and 40 microliters g-1 h-1 in skeletal muscle and skin respectively with corresponding figures during anaesthesia of 3 microliters g-1 h-1 and 10 microliters g-1 h-1 respectively.

Animals↗
PubMed1983

Ethanol metabolism in heavy drinkers after massive and moderate alcohol intake.

Some alcoholics have a regular daily alcohol consumption of more than 100 g. In preliminary observations we had the impression that the claimed alcohol intake in such 'heavy drinkers' was higher than could be accounted for by the ethanol elimination rate as measured routinely at 10 mmol/l (0.5 g/l). We therefore measured the ethanol elimination rate at very high blood ethanol concentrations of 40-80 mmol/l (2-4 g/l) found in eight alcoholics following heavy alcohol intake by measuring the falling blood ethanol concentrations until being less than 1 mmol/l. The elimination rate, on average 83 mumol/min per 1 blood, was about 49% higher than the elimination rate measured at 10 mmol/l in the same subject, being on average 58 mumol/min per 1/blood (paired t-test, P less than 0.05). The elimination rate following the high initial ethanol concentrations remained high until the concentration was below 5 mmol/l. Calculations of elimination rates are based on a number of assumptions concerning the physiologic and metabolic conditions. We examined specifically if the concentration-time curves could be adequately described by assuming metabolism according to a Michaelis-Menten pathway with a low Km value (simulating alcoholdehydrogenase with Km 0.2 mmol/l) or by assuming metabolism by two pathways with an alternative high-Km pathway with Km about 10 mmol/l. It was not necessary, in the statistical analysis, to include an alternative high-Km pathway. On the other hand, the data does give room for up to 50% elimination via such alternative pathways. The elimination rate at the high concentrations corresponded roughly to the claimed daily alcohol intake; furthermore the measured elimination rate at the lower concentrations were similar to values in non-alcoholics.

Alcohol Drinking↗
PubMed1982

[Acute scrotum].

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Acute Disease↗
PubMed1982

Hepatic galactose elimination kinetics in the intact pig.

The hepatic galactose elimination kinetics was studied in eight anaesthetized pigs by hepatic vein catheterization. Galactose was given as successive constant intravenous infusions so that steady-state concentrations, ranging from 50 mumol/l to 8 mmol/l, were obtained. Concentrations were measured in a peripheral artery and in the hepatic veins. Hepatic blood flow was determined by constant infusion of indocyanine green. The elimination kinetics is described by a mathematical model which assumes that the liver sinusoids are perfused with unidirectional blood flow and that the elimination in the hepatocytes takes place according to Michaelis-Menten kinetics. This creates a decreasing sinusoidal blood concentration from the inlet to the outlet of the liver. The estimated maximal elimination rate, Vmax, was on average 0.67 mmol min-1 kg-1 liver (range 0.55-0.95) and the half saturation concentration Km 0.25 mmol/l (0.12-0.58). The estimate of Km is similar to the value found in the isolated perfused pig liver (0.23 mmol/l), whereas the estimate of Vmax is about 50% higher (0.43 mmol min-1 kg-1 liver), probably due to both extrahepatic elimination in the splanchnic area and a better function of the liver in situ than in the isolated preparation.

Animals↗