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A Nissen

Publications and source records attributed to A Nissen.

13 recordsLinked to original sources
PubMed2000

Drug resistance-associated factors in primary and secondary glioblastomas and their precursor tumors.

Malignant gliomas are largely resistant to current chemotherapeutic strategies often displaying a multidrug-resistant phenotype. Mechanisms involved in drug resistance are reduced cellular drug accumulation through membrane efflux pumps, drug detoxification as well as alterations in drug target specificity. In 27 primary and 17 secondary glioblastomas and their astrocytic precursor tumors, we studied the immunohistochemical expression profile of P-glycoprotein (P-gp), multidrug resistance-associated protein (MRP), lung resistance-related protein (LRP), metallothionein, and topoisomerase II alpha. Glial tumor cells in all glioblastomas showed constant up-regulation of LRP, MRP, and topoisomerase II alpha. P-gp was found in 90% of the primary and 60% of the secondary glioblastomas. In precursor tumors, these drug resistance-related factors were expressed in varying proportions. Metallothionein, also found in normal and activated astrocytes, was retained in all neoplastic phenotypes. Furthermore, metallothionein, P-gp, LRP, and topoisomerase II alpha were strongly expressed by normal and neoplastic vessels which may confer to impaired penetration of therapeutic agents through the blood-brain and blood-tumor barrier. However, the expression profiles of drug resistance-related proteins neither differed between primary and secondary glioblastomas nor revealed any correlation to precursor or recurrent tumors. Nevertheless, inhibition of these factors may be promising approaches to the management of malignant gliomas.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1999

[National surveillance of Helicobacter pylori eradication in Denmark. Results based on registration of 34.582 drug prescriptions].

We wanted to characterize the use of H. pylori eradication therapy in Denmark (inhabitants 5,227,862). All H. pylori eradication treatments from a nation wide database covering all drug prescriptions in the period January 1994-June 1996 were identified. We found 28,784 out-patients having a prescription with drugs for H. pylori eradication, accounting for 34,582 prescriptions in total. The incidence of new consumers was 220 per 10(5) inhabitants per year, with a maximum at 70-79 years of age. Eighty-six percent of the patients had only one treatment course. Forty-five percent had an anti-ulcer drug prescribed 1-12 months after the H. pylori eradication therapy. Consumption of antibiotics used for H. pylori eradication accounted for 1.4% of the total consumption of antibiotics. In conclusion, the incidence of H. pylori eradication therapy was fairly stable but with changes in the pattern of drug regimens used. Anti-ulcer drugs were often given after H. pylori eradication therapy, suggesting an inappropriate use of eradication treatment.

Adult↗
PubMed1998

National surveillance of Helicobacter pylori eradication therapy in Denmark. Results from registration of 34,582 prescriptions.

BACKGROUND: We wanted to characterize the use of Helicobacter pylori eradication therapy in Denmark (5,227,862 inhabitants). METHODS: All H. pylori eradication treatments from a nationwide database including all redeemed drug prescriptions in the period January 1994 to June 1996 were identified. So were all outpatients receiving a drug prescription for H. pylori eradication. RESULTS: We recorded 34,582 prescriptions for H. pylori eradication therapy given to 28,784 patients. The incidence of new consumers was 220 per 10(5) inhabitants per year, with a maximum at 70-79 years of age. Eighty-six per cent of the patients had only one treatment course. In 16% of the eradication therapies, nonsteroid anti-inflammatory drugs had been prescribed within the previous 3 months, and 45% had an anti-ulcer drug prescribed 1-12 months after the H. pylori eradication therapy. Consumption of antibiotics used for H. pylori eradication accounted for 1.4% of the total consumption of antibiotics. CONCLUSIONS: The incidence of H. pylori eradication therapy was fairly stable but with changes in the pattern of drug regimens used. Anti-ulcer drugs were often given after H. pylori eradication therapy, suggesting an inappropriate use of treatment.

Adolescent↗
PubMed1996

[Individual-based statistics on drug utilization].

The Danish retail pharmacies' drug subsidy system is completely computerised. The data are person-identifiable, making it possible to chart the population's drug use from the perspective of the individual users. We undertook an analysis to explore the potential of this data source and to analyse the heavy drug users specifically. The analysis encompassed all 890,352 prescriptions presented by Odense citizens in 1991. There was a total sales volume of 32 million defined daily doses, consumed by 113,468 adult drug users, corresponding to 65.1% percent of the adult population. We found 2388 heavy drug users defined by an annual purchase of more than 2000 defined daily doses. Heavy drug users accounted for 1.4% of the adult population and 22.9% of drug sales. Heavy drug users were remarkably well characterised by their main therapeutic class which constituted a median of 47% of their drug use. A median of 97% of each heavy user's drugs were issued by one main prescriber. We conclude that heavy drug use generally can be ascribed to severe disease rather than to irresponsible prescribing. For the most important drug classes, we present various epidemiological measures of drug use, including one-year prevalence, incidence, duration of therapy and some measures of skewness in utilization. If analysed regularly these measures can disclose subtle trends in clinical drug use that would not be evident from the wholesale figures.

Adult↗
PubMed1996

Long-range air pollution and its impact on heavy metal accumulation in dippers Cinclus cinclus in Norway.

Heavy metals such as cadmium, lead and zinc are deposited in Norway as long-range transported air pollution, while copper deposition is of mainly local origin. This study examined whether the deposition influences the metal concentrations in dippers Cinclus cinclus. The lead concentration in dippers reflected the deposition pattern of long-range air pollution, with higher concentrations in Southern Norway than Central Norway and a significant decrease (>/=40%) between 1987 and 1994. For cadmium, copper and zinc there were no geographical or temporal variations in metal concentrations. For zinc, this lack of geographic and temporal variation probably reflects the fact that it is a homeostatically regulated metal. For both cadmium and copper, local sources are probably more important than long-range sources. Zinc and copper was at higher level in livers of females than in males during the egg laying period. The concentrations of zinc and copper in livers were positively correlated.

Journal Article↗
PubMed1994

Individualized drug utilization statistics. Analysing a population's drug use from the perspective of individual users.

The Danish retail pharmacies' drug subsidy system is completely computerized. The data are person-identifiable, making it possible to chart the population's drug use from the perspective of individual users. We decided to explore the potential of this data source and to analyse heavy drug users specifically. The analysis encompassed all 890,352 prescriptions presented by citizens of Odense in 1991. There was a total sales volume of 32 million defined daily doses consumed by 113,468 adult drug users, corresponding to 65.1% of the adult population. We found 2388 heavy drug users, defined by an annual purchase of more than 2000 defined daily doses. Heavy drug users accounted for 1.4% of the adult population and 22.9% of drug sales. They were remarkably well characterized by their main therapeutic class, which constituted a median of 47% of their drug use. A median of 97% of each heavy user's drugs were issued by one main prescriber. We conclude that heavy drug use can generally be ascribed to severe disease rather than to irresponsible prescribing. For the most important drug classes, we present various epidemiological measures of drug use, including 1-year prevalence, incidence, duration of therapy and some measures of skewness in utilization. If analysed regularly these measures can disclose subtle trends in clinical drug use that would not be evident from the wholesale figures.

Age Distribution↗
PubMed1992

Use of cimetidine and other peptic ulcer drugs in Denmark 1977-1990 with analysis of the risk of gastric cancer among cimetidine users.

The prevalence of use of peptic ulcer drugs in the Danish population is described at two points in time using registrations of applications for reimbursement. In 1977-81, the prevalence of use of cimetidine was 0.4% in men and 0.2% in women. In 1989-90, the prevalence of use of peptic ulcer drugs was 1.3% in men and 1.2% in women. The increase in prevalence was apparent in all age groups, but most pronounced at relatively old age. The median age of users increased from 55 years in 1977-81 to 63 years in 1989-90. The data indicated that a third of those who used peptic ulcer drugs in 1977-81 also used these drugs in 1989-90, conditional on surviving this period. The probability of becoming a long term user was highest for those who were 50-69 years in 1977-81. The incidence of gastric cancer was investigated in the cohort of persons who used cimetidine in 1977-81. An excess risk of gastric cancer was apparent in the first years after start of cimetidine use. This is thought to reflect a selection bias. Significantly increased incidence was also observed in women seven years or longer after start of cimetidine use (RR = 4.7; 95% CI: 1.7-10.3). This estimate was, however, based on only six cases, and a similar pattern was not observed in men.

Adult↗
PubMed1991

[The market of synonymous preparations in Denmark 1985-1990. A comparison of prices and quantities on the market].

The development of the market for synonymous drugs is investigated on the basis of groups of synonymous drugs in oral dosage forms where the difference between the price of the original preparation and the synonymous preparation(s) is at least 10%. The number of synonymous preparations has increased from 124 distributed among 76 groups in 1985 to 210 distributed amon 102 groups in 1990. In 1990, the total sale of synonymous groups constituted 31% of the total drug turnover. The cheap preparations constituted 47% of the sale in the synonymous groups. In 1985, the distributions were 27% and 44%, respectively. In 1990, the cheap preparations constituted 56% of the synonymous groups for preparations on the Danish market for the entire period form 1985 to 1990. Measured quantitatively (in defined daily dose), the consumption of the cheap preparations is greater than that indicated by the sale, 68% and 53%, respectively for the 15 largest synonymous groups in 1990. Consumption of the cheap preparations is high (75%) in group A (alimentary tract and metabolism) and considerably less (33%) in group R (respiratory system). Greater consumption of cheap preparations is observed within the synonymous groups with the greatest sale. The price level of the original preparations was only altered in a few cases after the synonymous preparations were marketed.

Denmark↗
PubMed1978

Occlusion of inferior vena cava--features by radionuclide venography.

Six adults with inferior vena caval obstruction are presented. Three were the results of surgical intervention, two were secondary to large thrombi, and one was due to pressure from a large renal-cell carcinoma and adjacent nodes. All underwent a modified approach of radionuclide venography, using a moderately large volume of sodium pertechnetate. Features characteristic of inferior vena caval obstruction were demonstrated in five of the six patients, and these various features are described and discussed.

Adenocarcinoma↗
PubMedDate not supplied

Expression of adhesion factors and degrading proteins in primary and secondary glioblastomas and their precursor tumors.

In tumor tissue specimens of 27 primary and 17 secondary glioblastomas and the precursor lesions, the immunohistochemical expression patterns of the membrane protein CD44s, the basal lamina proteins laminin, collagen IV, and fibronectin, the lectin galectin-3 recognizing tenascin and N-CAM as well as of the matrix-degrading enzymes matrix metalloproteinase MMP-2 and MMP-9, and cathepsin D were studied. Besides expression of basal lamina proteins in vessels, all glioblastomas and the precursor lesions showed strong immunoreactivity of CD44s, tenascin, galectin-3, and N-CAM which were restricted to solid tumor masses. Present in solid tumor areas, MMP-2, MMP-9 and cathepsin D were also strongly expressed by single tumors cells invading adjacent brain tissue at the infiltrative margin. Neither the expression pattern in primary and secondary glioblastomas nor in the precursor tumors revealed significant differences. There was also no intraindividual constant expression pattern during glioma progression or correlation with malignancy. Restricted expression of CD44s, galectin-3, tenascin and N-CAM in solid tumor masses seems to contribute to homotypic tumor cell adhesion while single tumor cells abolish this expression profile and acquire invasive activities by expression of cathepsin D, MMP-2 and MMP-9.

Adult↗