Biomedical subjects

K Andersen

Publications and source records attributed to K Andersen.

At least 55 records · Page 3Linked to original sources

PubMed1999

Characteristics of elderly who develop Alzheimer's disease during the next two years-a neuropsychological study using CAMCOG. The Odense Study.

OBJECTIVE: The aim of the study was to determine which cognitive functions first deteriorate in Alzheimer's disease (AD) and to identify persons who would become demented 2 years following an initial examination. PARTICIPANTS: A total of 2452 initially non-demented persons, aged 65-84 years and randomly drawn from the population, who were examined 2 years apart. MEASURES: CAMCOG, the cognitive section of CAMDEX (The Cambridge Mental Disorders of the Elderly Examination). Fourteen composite measures were constructed of the 60 CAMCOG items. RESULTS: During the 2-year period, 102 developed AD; this group had significantly lower scores on all of the 14 composite measures at baseline examination than the subjects who remained non-demented. The incident demented were significantly older than the non-demented, had less formal schooling, were more often unskilled and had lower verbal intellectual level. Logistic regression analyses showed that especially higher age, together with reduced recent and remote memory, low category verbal fluency and attentional deficiency, characterized incident demented 2 years before the diagnosis was made. CONCLUSIONS: Cognitive changes, which develop years before the AD diagnosis, can be identified by means of CAMCOG, but this instrument does not allow identification of persons who later develop AD with sufficient precision.

Aged↗

PubMed1999

Admission risk assessment by cardiac troponin T in unstable coronary artery disease: additional prognostic information from continuous ST segment monitoring. TRIM study group. Thrombin Inhibition in Myocardial Ischemia.

OBJECTIVES: We investigated whether the addition of 24 h of continuous vectorcardiography ST segment monitoring (cVST) for an early (within 24 h of the latest episode of angina) determination of cardiac troponin T (cTnT) could provide additional prognostic information in patients with unstable coronary artery disease (UCAD), i.e., unstable angina and non-Q wave myocardial infarction. BACKGROUND: Determination of cTnT at admission and cVST are individually reported to be valuable techniques for the risk assessment of patients with UCAD. METHODS: Two hundred and thirty-two patients suspected of UCAD were studied. Patients were followed for 30 days, and the occurrence of cardiac death or acute myocardial infarction (AMI) were registered. RESULTS: One ST segment episode or more (relative risk [RR] 7.43, p = 0.012), a cTnT level > or = 0.20 microg/liter (RR 3.85, p = 0.036) or prestudy medication with calcium antagonists (RR 3.31, p = 0.041) were found to carry independent prognostic information after multivariate analysis of potential risk variables. By combining a cTnT determination and subsequent cVST for 24 h, subgroups of patients at high (25.8%) (n = 31), intermediate (3.1%) (n = 65) and low risk (1.7%) (n = 117) of death or AMI could be identified. CONCLUSIONS: Twenty-four hours of cVST provides additional prognostic information to that of an early cTnT determination in patients suspected of having UCAD. The combination of biochemical and electrocardiographic methods provides powerful and accurate risk stratification in UCAD.

Adult↗

PubMed1999

Prognostic value of maximum ST-vector magnitude during the first 24 h of vectorcardiographic monitoring in patients with unstable angina pectoris.

AIMS: To assess the prognostic importance of alternate ways of quantifying myocardial ischaemia by continuous ST analysis, the maximum ST vector magnitude and the area under the ST vector magnitude trend curve during the first 24 h of continuous ST monitoring. METHODS AND RESULTS: During a 22-month period from 1991 to 1993, 195 patients admitted to our CCU with suspected unstable angina pectoris, were included in the study. During the first 24 h the patients were monitored for ischaemic episodes with computerized vectorcardiography, using a MIDA 1000 system. Twenty seven (14%) of the 195 patients died or had a non-fatal myocardial infarction within 1 year and the maximum ST vector magnitude among those patients was, on average, 201 microV compared with 118 microV in patients who survived 1 year free of myocardial infarction (P<0.01). The area under the ST vector magnitude trend curve was, on average, 1598 microVmin compared with 164 microVmin (P<0.01). By multivariate analysis, the maximum ST vector magnitude emerged as a superior predictor of death or myocardial infarction, compared with the area under the ST vector magnitude trend curve and the number of ST vector magnitude and ST change vector magnitude episodes. The maximum ST vector magnitude and age were independent predictors of death or non-fatal myocardial infarction within 1 year. CONCLUSION: Maximum ST vector magnitude during the first 24 h of vectorcardiographic monitoring seems to be a strong predictor of subsequent death or non-fatal myocardial infarction.

Aged↗

PubMed1999

Improved one-year survival after acute myocardial infarction in Icelandbetween 1986 and 1996.

During the last decade the treatment of patients with acute myocardial infarction (AMI) has changed dramatically. In order to evaluate the overall impact of these changes on mortality and morbidity, we collected data on all patients hospitalized for AMI in Reykjavik, Iceland, during the calendar years of 1986 and 1996. Demographical characteristics of AMI patients did not change significantly between study periods. One-year mortality decreased from 26.3 to 19.7% (p < 0.05). Patients discharged with aspirin or beta-antagonists as well as those who received thrombolytic therapy had decreased 1-year mortality both years. Patients discharged with diuretics, digoxin or antiarrhythmics had increased 1-year mortality. We conclude that the 25% reduction in 1-year mortality is partially due to changes in therapy.

Aged↗

PubMed1999

No advantage from splinting the wrist after open carpal tunnel release. A randomized study of 82 wrists.

To study the value of postoperative splinting after open carpal tunnel surgery, we randomly selected 82 wrists for 4 weeks of postoperative immobilization or no immobilization. The distributions of scar discomfort or pain and "pillar pain" were equal in the two groups both at 6 weeks and 6 months. Median sick leave was 6 weeks in both groups. Median VAS values for persistent discomfort and pain at 2 weeks, 6 weeks and 6 months were similar in the two groups. Grip strength was reduced compared to preoperative values by about 20% and keypinch strength by about 10% in both groups at 6 weeks and had returned to normal by 6 months. Pinch between the thumb and the tips of fingers 4 and 5 was considerably reduced postoperatively, but similar in both groups. We conclude that 4 weeks of postoperative immobilization confers no detectable benefit.

Absenteeism↗

PubMed1998

[Continuous ECG monitoring. A valuable technique in acute myocardial infarction].

Early diagnosis of acute myocardial infarction is important to enable myocardial injury to be limited by means of various treatments. Monitoring of vessel patency with vector cardiography or continuous 12-lead ECG recording is a form of surveillance that has been widely accepted in Sweden. In post-reperfusion therapy monitoring, there is approximately 80 per cent agreement between monitoring ST-segment changes and acute coronary cardiography. For risk stratification of patients with unstable angina or non-Q-wave infarction, ST-segment monitoring manifests great predictive power which is further enhanced by its combination with the measurement of highly specific markers of myocardial injury. Computerised techniques for continuous monitoring of multiple ECG leads have contributed much to our understanding of the dynamics of acute coronary heart disease. Valuable prognostic information is available in real time, early identification of myocardial injury is possible, and treatment strategies can be based upon more reliable grounds.

Electrocardiography, Ambulatory↗

PubMed1998

Heparin is more effective than inogatran, a low-molecular weight thrombin inhibitor in suppressing ischemia and recurrent angina in unstable coronary disease. Thrombin Inhibition in Myocardial Ischemia (TRIM) Study Group.

Thrombin has been suggested as one of the main pharmacologic targets in unstable coronary syndromes. Electrocardiographic signs of ischemia during continuous monitoring convey prognostic information in these patients. This study assessed the anti-ischemic and clinical effects of the novel low-molecular weight thrombin inhibitor inogatran in patients with unstable angina and non-Q-wave infarction without persistent ST-segment elevation on hospital admission. Within 24 hours of the last episode of chest pain, 324 patients were randomized to 72 hours of treatment with inogatran or heparin. Continuous ST-segment analysis with computerized vectorcardiography was used to monitor ischemia for 24 hours. The occurrence of cardiac events during the first 7 days were studied and compared with ischemic episodes during the initial 24 hours. The heparin-treated patients had less episodes of ischemia (ST vector magnitude [ST-VM]: 1 +/- 2.6 vs 2 +/- 4.5, p < 0.001 and ST change vector magnitude [STC-VM]: 3 +/- 4.7 vs 6 +/- 7.6, p < 0.001) than the patients receiving inogatran. This was paralleled by a lower incidence of the combined end point of death, nonfatal infarction, refractory or recurrent angina during the first 7 days for the heparin-treated patients (35%) compared with the inogatran-treated patients (50%) (p < 0.05). Patients who had episodes of ischemia in spite of anti-ischemic therapy were at increased risk of all events studied. Heparin is more effective than inogatran in suppressing myocardial ischemia and clinical events at short-term follow-up. Continuous ST-segment monitoring with vectorcardiography identifies nonresponders who are at an increased level of risk.

Adult↗

PubMed1998

A single conserved amino acid in the coat protein gene of pea seed-borne mosaic potyvirus modulates the ability of the virus to move systemically in Chenopodium quinoa.

Two isolates of pea seed-borne mosaic potyvirus, DPD1 and NY, which both infect pea (Pisum sativum) systemically, differ in their ability to move long distance in Chenopodium quinoa. DPD1 spreads to uninoculated leaves, whereas NY is restricted to the inoculated leaves. The NY isolate was found to move from cell to cell infecting all parts of the inoculated leaves, including the petiole. The coat protein (CP) coding region was identified as the determinant of long-distance movement. Virus chimeras containing the CP coding sequence of NY were restricted to inoculated leaves, whereas chimeras containing the CP coding sequence of DPD1 infected C. quinoa systemically. Mutational analysis of the CP demonstrated that changing the serine at position 47 of the NY CP to proline was sufficient to permit systemic spread of the NY(S47P) mutant. The reverse mutant, DPD1(P47S), in which the proline at position 47 of the CP was changed to serine, was restricted to inoculated leaves. The movement characteristics and CP sequences of 10 additional PSbMV isolates were determined. All isolates caused systemic infection in pea. In C. quinoa 6 of the isolates that were restricted to inoculated leaves had a serine at position 47. Two isolates that infected C. quinoa systemically had a proline at position 47. Two isolates, S6 and NEP-1, infected C. quinoa systemically, but had a serine at position 47 of the CP. This shows that although a proline/serine difference at position 47 of the CP determined systemic spread of the isolates DPD1 and NY, this amino acid alone does not govern the spread of PSbMV in C. quinoa.

Amino Acid Sequence↗

PubMed1998

Kinetics of conjugative transfer: a study of the plasmid pXO16 from Bacillus thuringiensis subsp. israelensis.

The aggregation-mediated conjugation system of Bacillus thuringiensis subsp. israelensis, encoded by the 200-kb plasmid pXO16, is highly potent in transferring itself and efficient in mobilizing other nonconjugative plasmids. The present study reveals some salient features of this conjugation system. Our observations can be summarized as follows: (i) The conjugative transfer takes about 3(1/2) to 4 min. For a 200-kb plasmid this corresponds to about 1 kb per second. (ii) The ability to transfer the plasmid seems to be evenly distributed among the donors. (iii) Functionally, the mating complex was found to consist of one donor and one recipient cell, even though aggregates comprising thousands of interconnected cells are formed. (iv) Having donated the plasmid, the donor needs a "period of recovery" of about 10 min before it can redonate the plasmid. (v) Secondary transfer, i.e., transfer from newly formed transconjugants, is delayed about 40 min. This maturation time exceeds the generation time, and it may indicate that to display donor activity, a surface protein (the aggregation substance) has to be uniformly incorporated into the cell wall. Lastly, we found that when the experiments were sufficiently short and when the recipient cells were in excess compared with the donors, the process of conjugation could be reasonably described by a kinetic model analogous to the Michaelis-Menten model for enzyme catalysis. This allowed us to estimate (vi) the maximal conjugation rate to be about 0.05 transconjugant per donor per minute, and (vii) the Km value, i.e., the concentration of recipient that results in half of the maximal conjugation rate, to be about 4 x 10(6) recipients/ml.

Bacillus thuringiensis↗

PubMed1998

Distribution of whaleworm (Anisakis simplex, Nematoda, Ascaridoidea) L3 larvae in three species of marine fish; saithe (Pollachius virens (L.)), cod (Gadus morhua L.) and redfish (Sebastes marinus (L.)) from Norwegian waters.

The frequency distribution of Anisakis simplex L3 larvae between host tissues was investigated in three host species: saithe, cod and redfish. Fish were sampled from Norwegian coastal waters and examined for the presence of A. simplex in muscle and viscera. In all three of the host species, A. simplex larvae were most frequently detected in the viscera; the percentages of total infection for saithe, cod and redfish were 99.6%, 97.8% and 88.0%, respectively. In general, the distribution patterns of A. simplex L3 between muscle and viscera were not significantly affected by host size. The observations that distributions vary between species and are not affected by host size do not support an earlier hypothesis which states that A. simplex L3 distributions are determined by an optimal pre-encapsulation migratory distance within host tissues. In contrast, it is suggested that A. simplex L3 distributions are governed by the conditions encountered within host tissues, and are possibly related to the availability of nutrients.

Animals↗

PubMed1998

Radiosynthesis of [11C]Lu 29-024: a potential radiotracer for 5HT2 receptors PET studies.

For mapping 5-HT2 receptors in the central nervous system with positron emission tomography (PET), 2,5-dimethyl-3-(4-fluorophenyl)-1-(1-[11C]methyl-4-piperidinyl)-1H-indol e ([11C]Lu29-024) has been prepared. The precursor for the radiosynthesis of [11C]Lu29-024 was obtained in an overall yield of 53% by a convenient five-step synthesis; its reaction with [11C]methyl iodide afforded [11C]Lu29-024 in 35-50% radiochemical yield (decay corrected) in 45 to 50 min with a specific radioactivity ranging from 11 to 15 GBq/micromol. Following i.v. injections into rats, the analysis of plasma samples showed that the metabolism of [11C]Lu29-024 was rapid and extensive (60% of the original tracer was metabolized at 40 min). In contrast, only unmetabolized [11C]Lu29-024 could be detected in brain tissue. These biological results suggest that labeled metabolites have no access to brain tissue and further propose [11C]Lu29-024 as an interesting tool for PET studies of brain 5HT2 receptors.

Animals↗

PubMed1998

Enzyme-linked immunosorbent assay of epidermal growth factor receptor in lung cancer: comparisons with immunohistochemistry, clinicopathological features and prognosis.

The prognostic role of epidermal growth factor receptor (EGFR) remains controversial in patients with lung cancer. Previous assays for EGFR have primarily been qualitative or, at best, semiquantitative. In the present study, using fresh-frozen tissue from 190 unselected lung cancer patients, quantification of EGFR (EGFR(ELISA)) using a recently developed enzyme-linked immunosorbent assay (ELISA) technique was compared with results (EGFR(IHC)) obtained using immunohistochemistry (IHC). Correlation between results obtained by the two different techniques was highly significant (r(s) = 0.63, P < 0.001, n = 190). This correlation improved even further (r(s) = 0.76) when sections were estimated using an IHC score that took into account percentage staining, intensity and relative tumour area. Furthermore, the relationship between clinicopathological features and prognosis was identical for the two methods. The expression of EGFR was highest in squamous cell carcinomas, but it was not correlated with other characteristics such as age, sex, histological grading, stage or prognosis. We conclude that evaluation of EGFR content using IHC and ELISA produces comparable results.

Adult↗

PubMed1998

Allergens in combination have a synergistic effect on the elicitation response: a study of fragrance-sensitized individuals.

Perfume ingredients were chosen as model substances to study the effect of allergens in combination on the elicitation response. Two groups of eczema patients were studied. One consisted of 18 subjects with a contact allergy to two fragrance substances and the other was a control group of 15 subjects allergic to only one of the same two fragrance substances. The test and matched control subject were patch tested in exactly the same way with two allergens applied in serial dilution in separate chambers on one side and combined in one chamber on the other side of the upper back. The assessment of reactions was carried out on day 3 by clinical grading and laser Doppler flowmetry, and the extent of the reaction was measured in millimetres. The data were analysed by logistic dose-response models. It was found that the combination of two allergens in individuals allergic to both substances had a synergistic effect on the elicitation response evaluated by all three methods. The 1 : 1 mixtures of the two allergens elicited responses as if the doses were three to four times higher than those actually used, which is significantly more than expected if an additive effect had been present. In the control group, no increased response was seen to the combined allergens compared with the allergens tested separately. The synergistic effect demonstrated is likely to apply to other contact allergens as well and should be taken into account in designing diagnostic tests and performing safety assessments.

Allergens↗

PubMed1998

Role of echocardiography in systemic arterial embolism. A review with recommendations.

The ability of echocardiography to diagnose sources of embolism and the role of the examination in the prediction of thromboembolism are reviewed. In addition, the yield of transthoracic (TTE) and transoesophageal echocardiography (TEE) is analysed in patients with suspected embolism and guidelines are proposed for performing echocardiography in this setting. In general, echocardiography is reliable for diagnosing sources of embolism and this applies in particular to TEE in the case of atrial, valvular, and aortic abnormalities. However, the method is useful for predicting embolism in a few cases only. There is a substantial risk in the event of mobile or protruding thrombi, but screening for these and other markers of thromboembolism seems to be unproductive in most groups of risk patients. Yet, in the presence of atrial fibrillation, echocardiography may be helpful in defining patients with an otherwise normal heart and low risk of embolism--and in defining the relatively rare patient with a clinically low-risk profile but moderate-to-severe left ventricular systolic dysfunction and a high risk of embolism. TEE-guided conversion of atrial fibrillation without weeks of preceding anticoagulation may prove useful, after further investigation. The risk of embolism in relation to the size and mobility of valvular vegetations has remained controversial. In patients with suspected recent embolism, TTE results in less than 5% new therapeutic consequences. In those with a normal TTE, the yield of TEE seems to be equally low. We therefore recommend a selective strategy: TTE and TEE can be omitted when a cardiac source of embolism appears from the clinical setting and in most patients with an obvious predisposition to cerebrovascular disease. However, in the latter cases TTE should be performed if indicated by the clinical situation, e.g. in the presence of fever and murmur. TTE is also recommended when there are no obvious markers of primary vascular disease. To preclude very rare sources of embolism (e.g. atrial thrombi despite sinus rhythm), supplementary TEE is recommended in younger patients in whom primary vascular disease is very unlikely. The diagnosis by TEE of common conditions such as atrial septal aneurysms and patent foramen ovale cannot, however, be taken as proof of the mechanism of a systemic arterial occlusive event; thus it is difficult to change therapy on the basis of such diagnoses.

Algorithms↗

PubMed1998

Noncardiac thoracic surgery in children. A retrospective study.

A retrospective study of noncardiac thoracic surgery in children (age < 16 years) comprised 126 patients consecutively operated on over a 10-year period. The surgical procedures included chest-tube insertion for neonatal pneumothorax in 33 children, 12 of whom died within 5 days after birth. Primary intrathoracic disorders were treated in 55 cases, mainly congenital pulmonary malformations in the youngest and traumatic conditions in the oldest. There were no early postoperative deaths in this group, but seven children were dead at the time of follow-up. In 38 children surgery was performed for involvement of intrathoracic organs secondary to other, often malignant diseases. Eleven of these children were dead at follow-up. Noncardiac thoracic surgery is thus required for a number of reasons in children and is well tolerated, although serious primary disease can increase mortality.

Adolescent↗

PubMed1998

Focal, continuous spikes suggest cortical developmental abnormalities. Clinical, MRI and neuropathological correlates.

OBJECTIVES: Widespread use of MRI now gives us increased insights into the different expressions of malformations of cortical development (MCD). The heterogeneity of these disorders are reflected by their varied clinical and neuroimaging features. Characteristic and intense scalp EEG abnormalities have been described in some patients. MATERIAL AND METHODS: We report the MRI and clinical findings of 3 adult patients (age 32-36) with a peculiar EEG pattern of distinct, localized, fast, continuous spiking. These patients represent all patients with such EEG findings that have been recognized by the first author during 9 years. RESULTS: MRI showed MCDs in all, respectively hemimegalencephaly, a subcortical heterotopion, and a focal cortical dysgenesis. The EEG findings had been stable since childhood and were posteriorly located. Two patients had fairly well controlled epilepsy in adult age. The third patient was incapacitated by persistent seizures and was treated with surgery. Histologically cortical dysplasia with neuronal clusters was found in this patient. Variable degrees of cognitive dysfunction were present in all. CONCLUSION: Focal, continuous, fast spiking is an unusual scalp EEG pattern. It is not an inevitable sign of severe epilepsy. It may suggest an MCD. It is not yet clear to what extent such findings are predictive of a dysgenetic etiology of epilepsy.

Action Potentials↗

PubMed1998

Smoking habits among pregnant women in Norway 1994-95.

AIMS: To investigate the smoking prevalence the last three months before pregnancy and at 18 weeks of gestation among women in Norway and to evaluate the impact of pre-pregnancy smoking habits, maternal age, level of education, civil status and parity on smoking cessation. MATERIAL AND METHODS: A prospective, multicenter survey. The study population included 4 766 pregnant women who attended a routine ultrasound examination at 18 weeks of pregnancy in six Norwegian hospitals during the period from September 1994 to March 1995. Smoking habits before and during pregnancy were recorded. RESULTS: The point prevalence of self-reported daily smoking among the women three months before the pregnancy was 34%. At 18 weeks of pregnancy, 21% of the women reported smoking daily (p<0.001). A multiple logistic regression analysis revealed that a low number of cigarettes smoked per day during the last three months before pregnancy was the best predictor for smoking cessation. Educational level, maternal age, parity and civil status were also statistically significant contributors to smoking cessation. Eighty percent of the women who were unable to stop smoking, reported a reduction in cigarette consumption. The mean number of cigarettes per day was reduced from 13.9 before pregnancy to 7.3 at 18 weeks of pregnancy (p<0.001). CONCLUSION: In a national survey, 21% of the pregnant women reported smoking daily in the second trimester. Thirty-eight percent of the women who were daily smokers before the pregnancy stopped smoking in early pregnancy. A low cigarette consumption prior to the pregnancy was the best predictor for smoking cessation.

Adolescent↗

PubMed1998

Minimally invasive direct coronary artery bypass grafting without cardiopulmonary bypass in combination with intraoperative percutaneous transluminal coronary angioplasty for palliative coronary revascularization in a heart transplant recipient.

The use of minimally invasive direct coronary artery bypass grafting without cardiopulmonary bypass in combination with intraoperative percutaneous transluminal coronary angioplasty for myocardial revascularization in a heart transplant recipient is reported.

Angioplasty, Balloon, Coronary↗