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K Jensen

Publications and source records attributed to K Jensen.

At least 145 records · Page 8Linked to original sources
PubMed1995

Introduction of a novel self-injector for sumatriptan. A controlled clinical trial in general practice.

A novel self-injector for the administration of subcutaneous sumatriptan in the treatment of migraine attacks was tested in 138 patients recruited by family physicians in Denmark: 108 patients completed the initial double-blind, crossover part of the study. Sumatriptan 6 mg s.c. was significantly better than placebo at 30, 60, 90 and 120 min after injection in relieving moderate or severe headache to mild or none as well as relieving any headache to none. At 60 min after injection, the treatment response rate was 61% for sumatriptan and 6% for placebo. During the following open-phase trial of four attacks treated with sumatriptan, treatment response rates were 68-74%. During the total of 538 attacks treated, 12 attempts at using the self-injector failed. In the double-blind and open phases, 81% and 90% of patients respectively found the device easy or very easy to use. Adverse effects were benign and short-lasting, but led seven patients to discontinue the study. In conclusion, subcutaneous sumatriptan administered with a novel self-injector is an effective treatment for migraine compared to placebo in patients treated by their family physician.

Adult↗
PubMed1995

Gliadin-specific T cell responses in peripheral blood of healthy individuals involve T cells restricted by the coeliac disease associated DQ2 heterodimer.

Coeliac disease (CD) is probably caused by an abnormal immune response towards wheat gliadin in the small intestine. We found that gliadin-specific T cells from the small intestinal mucosa of HLA-DQ2 positive CD patients were almost exclusively restricted by the disease-associated DQ2 molecule. In the peripheral blood of CD patients, a large proportion of gliadin-specific T cells were found to be restricted by DQ molecules, including DQ2, but many were instead restricted by DR or DP molecules of the patient. We have now investigated gliadin-specific T cell responses in peripheral blood from healthy individuals. Four of 20 persons tested had strong in vitro responses and were used as donors for gliadin-specific T cell clones. We found gliadin-specific T cells restricted by the CD-associated DQ2 molecule in peripheral blood for two of these four individuals. It is the presence of such T cells also in the small intestinal mucosa which seems typical of CD.

Antibodies, Monoclonal↗
PubMed1995

The use of non-medical/alternative treatment in multiple sclerosis. A 5 year follow-up study.

Forty-nine patients (22 males, 27 females) were examined and interviewed with 5 years interval in order to determine the extent of the use of non-medical (alternative) treatment and whether the use influenced the natural course of multiple sclerosis (MS). Using clinical course, Kurtzke Disability Status scale, bladder and bowel function, neuropsychological tests, psychological tests, divorce and self-assessment score as parameters, it was found that non-medical treatment did not alter the course of MS. To confirm this result a clinical trial in a controlled design is needed. The use of non-medical treatment declined over the 5 years from 55% to 27%. The use of non-medical treatment could be interpreted as an indicator of psycho-social difficulties in MS patients.

Adult↗
PubMed1994

Classification of wheat varieties by isoelectric focusing patterns of gliadins and neural network.

Classification of wheat varieties, using isoelectric focusing patterns of the gliadins, image processing and neural networks, is described. The method was compared to a statistical classification method, discriminant analysis. The isoelectric point and the area of each band were calculated by image processing. Different methods of presenting the electrophoretic patterns to the neural network were studied. The most effective method was transformation of the electrophoretic pattern to a small (11 x 47 pixels) representation of the original digitized image, which was presented to the neural network as a vector. The neural network was trained with a number of patterns and tested with new patterns from different electrophoretic runs of the same wheat varieties. In this study we used ten different wheat varieties and the neural network was able to classify 95.5% of the patterns correctly. The statistical classification method classified the same data set 91.8% correctly. We conclude that both the neural network and discriminant analysis were able to classify the patterns correctly with a high degree of certainty. The patterns that were misclassified were indistinguishable by visual inspection.

Discriminant Analysis↗
PubMed1994

The Mallory body: morphological, clinical and experimental studies (Part 1 of a literature survey).

To aid understanding of markers of disease and predictors of outcome in alcohol-exposed systems, we undertook a literature survey of more than 700 articles to view the morphological characteristics and the clinical and experimental epidemiology of the Mallory body. Mallory bodies are filaments of intermediate diameter that contain intermediate filament components (e.g., cytokeratins) observable by conventional light microscopy or immunohistochemical methods, identical in structure regardless of initiating factors or putative pathogenesis. Although three morphological types can be identified under electron microscopy (with fibrillar structure parallel, random or absent), they remain stereotypical manifestations of hepatocyte injury. A summary of the conditions associated with Mallory bodies in the literature and their validity and potential etiological relationships is presented and discussed, including estimates on the combined light microscopic and immunohistochemical prevalences and kinetics. Emphasis is placed on proper confounder control (in particular, alcohol history), which is highly essential but often inadequate. These conditions include (mean prevalence of Mallory bodies in parentheses): Indian childhood cirrhosis (73%), alcoholic hepatitis (65%), alcoholic cirrhosis (51%), Wilson's disease (25%), primary biliary cirrhosis (24%), nonalcoholic cirrhosis (24%), hepatocellular carcinoma (23%), morbid obesity (8%) and intestinal bypass surgery (6%). Studies in alcoholic hepatitis strongly suggest a hit-and-run effect of alcohol, whereas other chronic liver diseases show evidence of gradual increase in prevalence of Mallory bodies with severity of hepatic pathology. Mallory bodies in cirrhosis do not imply alcoholic pathogenesis. Obesity, however, is associated with alcoholism and diabetes, and Mallory bodies are only present in diabetic patients if alcoholism or obesity complicates the condition. In addition, case studies on diseases in which Mallory bodies have been identified, along with pharmacological side effects and experimental induction of Mallory bodies by various antimitotic and oncogenic chemicals, are presented. Mallory bodies occur only sporadically in abetalipoproteinemia, von Gierke's disease and focal nodular hyperplasia and during hepatitis due to calcium antagonists or perhexiline maleate. Other conditions and clinical drug side effects are still putative. Finally, a variety of experimental drugs have been developed that cause Mallory body formation, but markedly different cell dynamics and metabolic pathways may raise questions about the relevance of such animal models for human Mallory body formation. In conclusion, the Mallory body is indicative but not pathognomonic of alcohol involvement. A discussion on theories of development and pathological significance transcending the clinical frameworks will be presented in a future paper.

Abetalipoproteinemia↗
PubMed1994

Multiple sclerosis: correlation of anxiety, physical impairment and cognitive dysfunction.

The aim of the study was to examine the correlation between anxiety and physical impairment and to discover whether anxiety correlated with specific forms of cognitive dysfunction. Ninety-four patients (42 females, 52 males) with definite MS entered the study. Anxiety was measured using the State-Trait Anxiety Inventory, physical impairment by means of the Kurtzke Disability Status scale, and cognitive impairment by using the Trail Making, Symbol Digit Modalities, Auditory Verbal Learning, Story Recall and the Recurring Figures tests. Moderately handicapped patients (DSS 4-5) showed signs of anxiety, and physical impairment correlated with anxiety (p < 0.05; d.f. 1.92). Trail Making also correlated with anxiety (p < 0.01; d.f. 1.86). On the basis of the results of this and previous studies, it is concluded that anxiety can be a sign of cognitive dysfunction, physical impairment or social strain.

Adult↗
PubMed1994

The effect of metoprolol upon blood pressure, cerebral blood flow and oxygen consumption in patients subjected to craniotomy for cerebral tumours.

Hypertension and cerebral hyperperfusion are often seen in the immediate postoperative period after craniotomy for supratentorial tumours. Metoprolol is known to attenuate the postoperative hypertensive response after hypotensive anaesthesia and this study was carried out to evaluate the effect of metoprolol on cerebral blood flow (CBF) and cerebral metabolic rate of oxygen (CMRO2) before extubation and cerebral arteriovenous oxygen content difference (AVDO2), mean arterial blood pressure (MABP), PaO2 and PaCO2 in a 180-min period after extubation. Twenty patients anaesthetized with thiopentone, fentanyl, nitrous oxide 67%, and halothane 0.5% were randomized to receive intravenous metoprolol or placebo at the end of the peroperative period. There were no significant differences in CBF- and CMRO2 values between the two groups. In the period between closure of the dura and 5 min after extubation, an increase in MABP was observed in the control group (P < 0.05), but not in the metoprolol group. During the same period a decrease in AVDO2 was observed in both groups (P < 0.05); during the next 10 min an increase was observed, but with no difference in AVDO2 values between the groups. A higher level of PaO2 in the metoprolol group was observed in the postoperative period. These findings suggest that peroperative treatment with metoprolol reduces postoperative MABP but does not influence the cerebral blood flow and metabolism.

Adult↗
PubMed1994

The Bullard laryngoscope. Reports of two cases of difficult intubation.

The Bullard laryngoscope is a new combination of a fibreoptic light source and an anatomically shaped rigid blade, to aid visualization of the larynx. We present two patients with expected severe difficult endotracheal intubation and describe their anaesthetic management. Our experience confirms previous observations which showed that the Bullard laryngoscope provides an excellent view of the vocal cords in patients with severe difficult airways.

Epiglottis↗
PubMed1994

Effect of pregnancy on the prognosis for multiple sclerosis. A 5-year follow up investigation.

INTRODUCTION: The purpose of the study was to evaluate the effect of pregnancy and childbirth on the longterm prognosis for women with multiple sclerosis (MS). METHOD AND MATERIAL: A cohort of 39 women with definite MS were identified on 1.1.1986 using a reproducible selection method. The investigation was initiated in 1986 when handicap was evaluated by Kurtzke Disability Status Score (DSS). At a 5-year follow up 4 had died and 6 could not participate. There were 29 women in the investigation of whom 7 were childless, 10 had onset of MS at least 6 months after last childbirth, and 12 had onset of MS before or in connection with childbirth. Age and disease duration of the group was uniform. RESULT: At follow up the DSS significantly deteriorated (p = 0.008). The deterioration was seen particularly for childless women (p = 0.03) and women with onset of MS before or in connection with childbirth (p = 0.005). CONCLUSION: On the basis of this prospective investigation and the literature, it may be concluded that it is unlikely that pregnancy and childbirth have an influence on the longterm prognosis for MS. However, the conclusion must be interpreted with caution as the number of patients is small.

Adult↗
PubMed1994

Attempted suicide and contact with the primary health authorities.

In a study describing suicide attempters' approach to the health and social welfare authorities prior to a suicide attempt, it was found that one-fourth of the patients seeking help requested therapeutic consultations and only a few asked for medicinal treatment. Forty-four percent had taken newly prescribed medicine for the parasuicide. It is concluded that the availability of psychological support and a more restrictive prescription of medicine could have a preventive effect on parasuicidal behaviour. Patients suffering from depression and pain have more often than other patients been in contact with their general practitioner prior to the suicide attempt. Postgraduate courses for practitioners on depression diagnostics and suicidal behaviour are proposed as a measure in suicide prevention.

Adult↗
PubMed1994

Evaluation of methods for the detection of nasal carriage of Staphylococcus aureus.

In the present study we investigate the optimal methodology for determination of the nasal carriage rate of Staphylococcus aureus. Tests were performed on 91 healthy laboratory staff. The reproducibility of different sampling, transportation, storage and culture methods was examined. We compared sterile dry cotton wool swabs with sterile dry cotton wool swabs impregnated with charcoal and 5% blood agar plates with mannitol salt agar plates after different incubation periods. Finally, we investigated the detection rate for S. aureus following direct plating compared to storage in Stuart's transport medium for 7 days. There were no differences in isolation rates from the right or left nostril using either cotton or charcoal swabs. Charcoal swabs gave an increased isolation rate as compared to cotton swabs, and incubation in broth enrichment medium containing 6.5% NaCl also increased the isolation rate. Storage in Stuart's transport medium for 7 days gave an increase in isolation rate as compared to direct plating on blood agar. With mannitol salt agar plates the increase in isolation rate when incubation was performed for from 2 to 4, 2 to 7, and 4 to 7 days was 5.9%, 16.7%, and 11.5%, respectively. For the detection of S. aureus nasal carriers we find the use of charcoal swabs and Stuart's transport medium combined with cultivation on mannitol salt agar for 7 days to be the optimal method.

Adult↗
PubMed1994

Estimation of nitrification and denitrification from microprofiles of oxygen and nitrate in model sediment systems.

The coupling between nitrification and denitrification and the regulation of these processes by oxygen were studied in freshwater sediment microcosms with O(2) and NO(3) microsensors. Depth profiles of nitrification (indicated as NO(3) production), denitrification (indicated as NO(3) consumption), and O(2) consumption activities within the sediment were calculated from the measured concentration profiles. From the concentration profiles, it was furthermore possible to distinguish between the rate of denitrification based on the diffusional supply of NO(3) from the overlying water and the rate based on NO(3) supplied by benthic nitrification (D(w) and D(n), respectively). An increase in O(2) concentration caused a deeper O(2) penetration while a decrease in D(w) and an increase in D(n) were observed. The relative importance for total denitrification of NO(3) produced by nitrification thus increased compared with NO(3) supplied from the water phase. The decrease in D(w) at high oxygen was due to an increase in diffusion path for NO(3) from the overlying water to the denitrifying layers in the anoxic sediment. At high O(2) concentrations, nitrifying activity was restricted to the lower part of the oxic zone where there was a continuous diffusional supply of NH(4) from deeper mineralization processes, and the long diffusion path from the nitrification zone to the overlying water compared with the path to the denitrifying layers led to a stimulation in D(n).

Journal Article↗
PubMed1994

Simulation Model of the Coupling between Nitrification and Denitrification in a Freshwater Sediment.

A model was constructed to simulate the results of experiments which investigated nitrification and denitrification in the freshwater sediment of Lake Vilhelmsborg, Denmark (K. Jensen, N. P. Sloth, N. Risgaard-Petersen, S. Rysgaard, and N. P. Revsbech, Appl. Environ. Microbiol. 60:2094-2100, 1994). The model output faithfully represented the profiles of O(2) and NO(3) and rates of nitrification, denitrification, and O(2) consumption as the O(2) concentration in the overlying water was increased from 10 to 600 muM. The model also accurately predicted the response, to increasing O(2) concentrations, of the integrated (micromoles per square meter per hour) rates of nitrification and denitrification. The simulated rates of denitrification of NO(3) diffusing from the overlying water (D(w)) and of NO(3) generated by nitrification within the sediment (D(n)) corresponded to the experimental rates as the O(2) concentration in the overlying water was altered. The predicted D(w) and D(n) rates, as NO(3) concentration in the overlying water was changed, closely resembled those determined experimentally. The model was composed of 41 layers 0.1 mm thick, of which 3 represented the diffusive boundary layer in the water. Large first-order rate constants for nitrification and denitrification were required to completely oxidize all NH(4) diffusing from the lower sediment layers and to remove much of the NO(3) produced. In addition to the flux of NH(4) from below, the model required a flux of an electron donor, possibly methane. Close coupling between nitrification and denitrification, achieved by allowing denitrification to tolerate some O(2) ( approximately 10 muM), was necessary to reproduce the real data. Spatial separation of the two processes (no toleration by denitrification of O(2)) resulted in too high NO(3) concentrations and too low rates of denitrification.

Journal Article↗
PubMed1994

Interaction of several related GC-box- and GT-box-binding proteins with the intronic enhancer is required for differential expression of the gb110 gene in embryonal carcinoma cells.

The molecular mechanisms by which expression of a gene is down-regulated after differentiation of F9 embryonal carcinoma cells into parietal endoderm-like cells was studied by characterizing the cis- and trans-regulatory elements of the gb110 gene. This gene encodes a putative RNA helicase, and its expression is down-regulated when F9 cells are differentiated with retinoic acid and cyclic AMP. The 5'-flanking region of the gene has all of the features of a GC-rich island promoter and seems to play only a minor role, if any, in the regulated expression. A 133-bp enhancer in the first intron was identified by transient chloramphenicol acetyltransferase assays that activated expression in undifferentiated F9 cells about 50- to 100-fold. As this enhancer was not active in differentiated F9 cells, it seems to be the prime mediator of the differentiation-specific down-regulation of the gb110 gene. Four different protein-binding sites, three of which contain GC- and GT-box motifs, were identified in the enhancer element. The fourth site, interacting with previously described transcription factor FTZ-F1/ELP, seems to be of minor importance for the activity of the enhancer. Mutational analysis showed that the cooperative interaction of several most likely related proteins with the three GC- and GT-box motifs was required for full enhancer activity. On the basis of their binding properties, at least two of these proteins seem to be identical or closely related to ubiquitous transcription factor Sp1. One of the GT-box-binding proteins was present in undifferentiated F9 cells but not, however, in its differentiated derivatives. The cell specificity of this transcription factor explains why the gb110 gene is not expressed or expressed only at low levels in parietal endoderm-like cells.

Animals↗
PubMed1994

Attempted suicide, depression and physical diseases: a 1-year follow-up study.

In the period January 1, 1990 to March 31, 1991 a sample of suicide attempters admitted to the Department of Psychiatry, Odense University Hospital, underwent a structured interview. In the study 52% of the patients interviewed were found to suffer from a somatic disease, and 21% were daily on analgesics for pain. Patients that suffered from a somatic disease differed from other suicide attempters in depression score, age, pain and the presence of psychosis. Fewer of the somatically ill suicide attempters had a psychosis. Patients complaining of pain were more often depressed and abused medicine. Statistically, the risk of repetition of parasuicide for patients with a somatic disease but without depression was significantly less. The 7 patients committing suicide were older and a tendency was found towards painful somatic diseases and depression as risk factors for suicide.

Adult↗
PubMed1994

The Mallory body: theories on development and pathological significance (Part 2 of a literature survey).

Drawing on data from a previously published literature survey on the clinical and experimental epidemiology of the Mallory body, we discuss current theories on its development in a pro et contra manner. Conclusions have been largely left open to the interpretations of the reader because many are still speculative. The main results of this study characterize Mallory bodies as stereotypical histological byproducts to diverse hepatic injuries (mostly alcohol associated) of questionable pathogenic importance. The temporal characteristics of Mallory bodies cast doubt on their role in hepatic neoplasia both as a disease marker and a causative agent, and prognosis studies suggest that they may be considered preterminal markers in some nonalcoholic liver diseases but remain prognostically unimportant in most studies on alcoholic patients. By similar line of inquiry, no consistent relationships may be found with disease severity or duration in alcoholic liver diseases. The roles of vitamin A deficiency and protein-calorie malnutrition are circumstantial. Drugs known to have calcium-antagonist properties and the physiological characteristics of the stress-response protein ubiquitin support the concept of defective protein systems in Mallory body pathogenesis. Disproportionate hepatic copper accumulation seems both epidemiologically and topographically associated with Mallory bodies, but these connections are largely unsupported by exposure studies. Many arguments still downplay the importance of uncoordinated changes in hepatic oxygen delivery and consumption, but ischemia-reperfusion studies suggest a role of oxygen-derived free radicals in the liver injuries under scrutiny. Finally, the role of Mallory bodies in the control system of hepatocyte function is addressed, and indirect evidence lends credence to a cybernetic approach in future study designs. It is reasonable to assume that different elements of a multifactorial setting operate with varying intensity over time as this may account for some of the controversies that exist. In conclusion, the biological significance of Mallory bodies is still mystery. It is not known whether Mallory bodies represent an epiphenomenon or play a role themselves in the initiation and continuation of liver damage.

Animals↗
PubMed1994

Multiple sclerosis: methodological aspects of cognitive testing.

In a cross-sectional study of 94 patients (42 males, 52 females) with definite multiple sclerosis (MS) in the age range 25-55 years, the correlation of neuropsychological tests with the ability to read TV-subtitles and with the use of sedatives is examined. A logistic regression analysis reveals a significant correlation between results of an attention and perceptual motor speed test i.e. Symbol Digit Modalities test and the ability to read TV-subtitles, but no correlation was found with another attention and perceptual motor speed test, or verbal or visual memory. No correlation between the use of sedatives and results on neuropsychological tests was found. Anxiety was not correlated with the ability to read TV-subtitles. It is concluded that visual deficits but not the use of sedatives may be a confounding factor in neuropsychological testing in MS.

Adult↗