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E Rasmussen

Publications and source records attributed to E Rasmussen.

At least 19 recordsLinked to original sources
PubMed2006

A prospective study of medically treated acute type B aortic dissection.

OBJECTIVE: To study prospectively aneurysm formation, need of surgery, incidence of rupture and mortality in patients with conservatively treated acute type B aortic dissection. METHODS: All patients referred to us with acute type B dissection between January 1990 and December 2001 were candidates for this prospective treatment and follow-up study. Patients deemed not to be in need of acute surgical repair were included after aggressive antihypertensive treatment. The follow-up protocol included close blood pressure control, clinic visits with physical examination, chest x-ray and spiral CT or MRI at 3 and 6 months and annually thereafter. RESULTS: Sixty-six patients were followed for a mean of 79 months (range 22-179). The actuarial survival rate was 82% at 5 years and 69% at 10 years. Eighty-five percent remained free from dissection-related death at 5 years and 82% at 10 years. Ten patients (15%) developed aneurysm (>6 cm) of the dissected aorta. Three of these 10 patients died from aortic rupture and 2 underwent elective surgical repair. Of the 56 patients without aneurysm, one died from rupture and one died suddenly for causes unknown. One patient was treated with endovascular stent-graft. Five patients sustained a new type A aortic dissection which in all but one were fatal. In 26 patients the initial dissection was categorized as intramural hematoma. Twelve of these patients had, in addition to the hematoma, areas with localized dissection/ulcer-like projection. The latter was found to be a predictor of aortic event (dissection-related death, rupture, new type A aortic dissection, aneurysm formation) during follow-up, as was an initial diameter of >4.0 cm at first CT-scan during the acute event. CONCLUSIONS: Conservatively treated acute type B dissection has a low incidence of aneurysm formation and rupture during the chronic phase. These results must be matched or improved upon before endovascular stent-grafting or early aortic surgical repair can be regarded as the primary treatment of choice.

Acute Disease↗
PubMed2006

Immunogenicity of kappa-casein and glycomacropeptide.

Glycomacropeptide (GMP), arising from the cleavage of kappa-casein by chymosin or pepsin, has been correlated with a wide variety of biological activities including immunosuppression capacity, inhibition of pathogen invasion, and induction of satiety. Due to the interest in exploiting such potential of GMP, we aimed at characterizing the immunogenic properties of GMP as an indication of its potential allergenicity. Immunogenicity of kappa-casein and GMP were investigated using 2 animal models based on different routes of immunization: 1) mice immunized intraperitoneally or subcutaneously with either kappa-casein, polymerized GMP, GMP coupled to the immunogenic carrier ovalbumin, or GMP alone; 2) mice coadministered kappa-casein or GMP and cholera toxin. The specific antibody response to GMP was evaluated as well as the antigen-specific T-cell response. The results demonstrated that immunization or feeding with kappa-casein induced GMP-specific antibodies, whereas GMP per se lacked immunogenicity independently of the mode of presentation. The size of the presented form of GMP did not influence its immunogenicity. Because the results showed that GMP did not induce a specific T-cell response, we postulate that GMP lacks the ability to stimulate antigen-specific T cells.

Animals↗
PubMed2004

Interstitial lung disease, a common manifestation of newly diagnosed polymyositis and dermatomyositis.

OBJECTIVES: To estimate the prevalence and predictors of interstitial lung disease in newly diagnosed polymyositis and dermatomyositis. METHODS: A prospective study in which consecutive patients with newly diagnosed poly- and dermatomyositis, regardless of clinical symptoms of pulmonary disease, were investigated with chest x ray, high resolution computed tomography (HRCT), pulmonary function tests, and biochemical and autoantibody analysis. Patients with inclusion body myositis, malignancy, other defined inflammatory connective tissue diseases (CTDs), or antibody profile indicating other CTDs were excluded. RESULTS: Between March 1998 and September 2000, 26 new cases of poly- or dermatomyositis were diagnosed; 17 of those patients were included in the study. Interstitial lung disease (ILD), defined as radiological signs on chest x ray examination/HRCT or restrictive ventilatory defect, were found in 11 (65%) patients and were more common in men than in women. Arthritis and occurrence of anti-Jo-1 antibodies were found more often in patients with ILD than in those without. There was no statistically significant association between respiratory symptoms, other serological or laboratory variables and ILD. CONCLUSIONS: ILD is a common early manifestation in patients with poly- and dermatomyositis and is not always related to clinical symptoms. Chest x ray examination, HRCT, pulmonary function tests, and analysis of anti-Jo-1 antibodies should be included in the initial investigation of patients with myositis regardless of respiratory symptoms.

Adult↗
PubMed2003

Lung perfusion scintigraphy prior to lung volume reduction surgery.

PURPOSE: The aim of this study was to evaluate whether lung perfusion scintigraphy (LPS) contributes to the preoperative classification of emphysema heterogeneity in patients undergoing LVRS (lung volume reduction surgery) compared to classification based only on computed tomography (CT). MATERIAL AND METHODS: Forty-five potential candidates for LVRS were examined with CT and LPS. The distribution of emphysema within the lungs was visually classified into three categories: markedly heterogeneous, intermediately heterogeneous, or homogeneous. The results of the two imaging techniques were compared to an objective, CT-based computerized classification of heterogeneity. RESULTS: Visual evaluation of all 90 lungs resulted in 50 correct classifications based on CT, in 40 based on LPS and in 68 correct classifications based on the combination of CT and LPS. The combination was superior to CT alone (p<0.01) in classification of emphysema heterogeneity. There was no significant difference between the evaluations based on either CT or LPS. CONCLUSION: The combined information from CT and LPS are superior in assessing emphysema heterogeneity prior to LVRS.

Female↗
PubMed2002

Visual classification of emphysema heterogeneity compared with objective measurements: HRCT vs spiral CT in candidates for lung volume reduction surgery.

The aim of this study was to investigate whether spiral CT is superior to high-resolution computed tomography (HRCT) in evaluating the radiological morphology of emphysema, and whether the combination of both CT techniques improves the evaluation in patients undergoing lung volume reduction surgery (LVRS). The material consisted of HRCT (with 2-mm slice thickness) and spiral CT (with 10-mm slice thickness) of 94 candidates for LVRS. Selected image pairs from these examinations were evaluated. Each image pair consisted of one image from the cranial part of the lung and one image from the caudal part. The degree of emphysema in the two images was calculated by computer. The difference between the images determined the degree of heterogeneity. Five classes of heterogeneity were defined. The study was performed by visual classification of 95 image pairs (spiral CT) and 95 image pairs (HRCT) into one of five different classes of emphysema heterogeneity. This visual classification was compared with the computer-based classification. Spiral CT was superior to HRCT with 47% correct classifications of emphysema heterogeneity compared with 40% for HRCT-based classification ( p<0.05). The combination of the techniques did not improve the evaluation (42%). Spiral CT is superior to HRCT in determining heterogeneity of emphysema visually, and should be included in the pre-operative CT evaluation of LVRS candidates.

Adult↗
PubMed2002

Determination of cardiac involvement in sarcoidosis by magnetic resonance imaging and Doppler echocardiography.

OBJECTIVES: To elucidate whether cardiac magnetic resonance imaging (MRI) could be useful in disclosing structural changes in the myocardium in sarcoidosis patients and to relate echo-Doppler derived indices of left ventricular function to electrocardiogram (ECG) findings. DESIGN: The MRI was performed in 18 consecutive patients with sarcoidosis. Left ventricular ejection fraction (LVEF), i.e. systolic function, was estimated echocardiographically by Simpson's two-dimensional method (n = 16). Diastolic function was estimated by age-corrected Doppler-derived indices: isovolumetric relaxation time (IVRT), deceleration time (DT) and early filling/atrial contraction ratio (E/A ratio). RESULTS: Eleven patients had conduction defects or dysrhythmias (ECG+) whilst seven patients had a normal ECG (ECG-). In two patients, high signalling, contrast-enhanced, isolated regions, suggestive of deposits, were seen in the left ventricular myocardium on MRI. Both these patients had abnormal ECGs and signs of systolic and/or diastolic dysfunction on echocardiography. LVEF was subnormal in seven of 10 of the ECG+ patients and in two of six of the ECG-. Signs of diastolic dysfunction were found in 59% and 56% of the measurements in the ECG+ and ECG- patients, respectively. CONCLUSION: We conclude (i) that myocardial deposits on MRI in sarcoidosis patients have a high specificity for cardiac involvement but a rather low sensitivity; (ii) that a substantial proportion of sarcoidosis patients with abnormal ECGs have echocardiographic signs of systolic and/or diastolic dysfunction.

Adult↗
PubMed2002

Visual grading of emphysema severity in candidates for lung volume reduction surgery. Comparison between HRCT, spiral CT and "density-masked" images.

PURPOSE: To investigate which of three types of CT imaging yielded the best results in estimating the degree of emphysema in patients undergoing evaluation for lung volume reduction surgery (LVRS), whether there was any difference in this regard between the cranial and caudal part of the lung, and whether the degree of emphysema had an impact on the estimation. MATERIAL AND METHODS: Four radiologists visually classified different degrees of emphysema on three different types of CT images into four groups. The degree of emphysema was calculated by a computer. The three types of images were as follows: HRCT images (2-mm slice thickness); spiral CT images (10-mm slice thickness); and density-masked images (spiral CT images printed with pixels below -960 HU, depicted in white). RESULTS: The conventionally presented images from HRCT and spiral CT yielded the same results (60% respective 62% correct classifications) in assessing the degree of emphysema irrespective of localisation. Significantly improved results were obtained when the spiral CT images were presented as density-masked images (74%). CONCLUSION: There was no difference between HRCT and spiral CT in assessing the degree of emphysema in candidates for LVRS. Improvement can be achieved by the use of density-masked images.

Absorptiometry, Photon↗
PubMed2001

Percutaneous retrieval of the Tulip vena cava filter: feasibility, short- and long-term changes--an experimental study in dogs.

PURPOSE: To evaluate experimentally the retrievability of the Tulip inferior vena cava (IVC) filter in an in vivo study. Changes which accompany venous healing after filter retrieval were investigated. METHODS: In 12 dogs, 23 filters were inserted percutaneously into the lumbar and intrahepatic segments of the IVC. Two weeks (n = 21 filters) or 3 weeks (n = 2 filters) after insertion, filter retrieval was attempted through an 11 Fr coaxial retrieval sheath system placed via the jugular vein. Follow-up studies before and after filter retrieval included cavography, computed tomography and intravascular ultrasound of the IVC. Seven dogs were killed immediately after filter retrieval to confirm short-term changes of the IVC, and 5 dogs were killed 6 months after filter retraction to evaluate long-term changes of the IVC related to filter retrieval. Post-mortem examinations and histologic specimens of the IVC were obtained to evaluate caval wall abnormalities secondary to filter removal. RESULTS: All but one filter were successfully retrieved 2 weeks post-implantation. However, 3 weeks after insertion, filter retrieval was impossible. There were no complications caused by filter extraction. Follow-up studies after filter retrieval revealed no significant changes in the integrity, morphology or composition of the IVC and pericaval tissue. Histologic examination 6 months after filter retrieval revealed only flimsy fibrotic intimal plaques at the sites of former hook insertion. CONCLUSION: The Tulip filter allows percutaneous insertion and retrieval up to 14 days after insertion, suggesting that it may be useful for either permanent or temporary prophylaxis against pulmonary embolism.

Animals↗
PubMed2001

A clustering approach for localizing disease susceptibility loci.

Latent class (LCA) and cluster analysis (CLA) were utilized to identify trait loci for the Genetic Analysis Workshop 12 simulated disease. These techniques create non-overlapping subsets of concordant and discordant affected relative pairs based upon identity-by-descent (IBD) allele sharing at sequences of markers. Subgroups with a large proportion of affected pairs are used to identify markers in proximity to disease susceptibility loci. Both methods are model-free and make use of information from affected and unaffected subjects. In analyses performed without knowledge of the true disease model, LCA and CLA identified regions containing five of the seven trait loci.

Alleles↗
PubMed2001

Thin-section CT vs spiral CT in candidates for lung volume reduction surgery: a comparison based on radiologists' subjective preferences.

The aim of this study was to investigate whether high-resolution (HRCT) or spiral CT was preferred in evaluating severe emphysema in patients undergoing lung volume reduction surgery (LVRS), whether there is any difference in this regard between the cranial and caudal part of the lung, and whether the degree of emphysema has an impact on the radiologists' preference. The study was performed by letting four radiologists compare images obtained with the two techniques (film pairs) and decide which technique they preferred or if the techniques were considered as equal in evaluating emphysema. In evaluation of 188 film pairs, the HRCT images were preferred in 56 %, spiral CT in 19 % and the techniques considered as equal in 25 %. Spiral CT images were preferred more often in the caudal part of the lung and in more advanced emphysema compared with the HRCT images. The study confirms our clinical assumption that use of both CT techniques are valuable in evaluating advanced emphysema and there may be technical as well as histopathological reasons for this.

Adult↗
PubMed2001

Definition of the phenotype.

Definition of the phenotype is a key issue in designing any genetic study whose goal is to detect disease genes. This chapter describes strategies to increase the power to detect susceptibility loci for complex diseases. A narrowly defined disease phenotype can offer advantages over broad definitions. Studies of clinical disease can also benefit from judicious selection of endophenotypes and related quantitative traits for analysis. The effect of diagnostic and measurement error is also discussed; power is maximized when strategies to reduce error are incorporated into a study design.

Alleles↗
PubMed2000

Effect of genetic cross on the detection of quantitative trait loci and a novel approach to mapping QTLs.

A genome-wide scan was conducted in two F(2) intercrosses, C57BL/6J (B6)xDBA/2J (D2) and BALB/cJ (C)xLP/J (LP), for three different phenotypes: basal locomotor activity, ethanol-induced locomotor activity, and haloperidol-induced catalepsy. For basal activity, significant quantitative trait loci (QTLs, LOD> or =4.3) were detected on chromosomes 9 and 19 for the CxLP intercross and chromosome 1 for the B6xD2 intercross. Significant QTLs for ethanol-induced activation were detected on chromosome 6 for the CxLP intercross, and on chromosomes 1 and 2 for the B6xD2 intercross. For haloperidol-induced catalepsy, significant QTLs were detected on chromosome 14 (two different QTLs) in the CxLP intercross, and chromosomes 1 and 9 in the B6xD2 intercross. These data illustrate the importance of the genetic cross for QTL detection. Finally, the data reported here, and elsewhere, are also used to demonstrate a novel approach to QTL detection and localization.

Animals↗
PubMed1999

Identification of quantitative trait loci for haloperidol-induced catalepsy on mouse chromosome 14.

Previous studies have established that neuroleptic-induced catalepsy in mice is a highly heritable trait. The current study focuses on the detection of quantitative trait loci (QTL) for haloperidol-induced catalepsy in a BALB/cJ x LP/J F(2) intercross. One thousand thirty-seven F(2) animals were phenotyped and divided into four categories: very responsive (RR), responsive, nonresponsive, and very nonresponsive (NN). The RR and NN phenotypes comprised approximately 18% each of the total and differed in their haloperidol sensitivity by >10-fold. Sex differed significantly between the NN and RR groups (chi(2) = 14.0; p <.0002); females comprised 58% of the RR individuals but only 38% of the NN individuals. The difference between the extreme phenotypes in the number of piebald animals was highly significant (chi(2) = 30, p <. 00001). Eight percent of the RR individuals were piebald compared with 30% of the NN individuals. A genome wide scan confirmed the presence of a QTL (peak LOD = 6.4) on chromosome 14 near the piebald (Ednrb) and 5-hydroxytryptamine(2A) (Htr2a) loci. Although the parental BALB/cJ and LP/J strains differed significantly in striatal 5-hydroxytryptamine(2A) receptor binding, no marked differences were detected between the phenotypic extremes. A second QTL was detected on chromosome 14 (peak LOD = 6.9), which was located more proximally and included the Chat locus. No QTLs were detected on chromosomes 1 and 9, thus differentiating this cross from previous results obtained for a C57BL/6J x DBA/2J intercross.

Animals↗
PubMed1998

Insulin-like growth factor 1 (IGF-I) effects on sex-specific cytochrome P450 enzymes in normal and hypophysectomised male rats.

The role of growth hormone (GH) in the regulation of the sex-differentiated rat cytochrome P450 (CYP) enzymes has been extensively studied. However, little is known about the involvement of insulin-like growth factor I (IGF-I) as a mediator in this regulation. We wanted to study if IGF-I had effects on sex-differentiated CYP enzymes and to compare the effects of IGF-I to the effects of GH. IGF-I, GH or saline was administered continuously via osmotic minipumps to normal and hypophysectomised rats for seven days. After treatment, the expression of several sex-differentiated liver enzymes (CYP2C11, CYP2C12), the female-dominant steroid 5alpha-reductase, and the male-dominant CYP3A2 enzyme was studied at mRNA, protein and/or functional levels. Our results demonstrate that IGF-I has marked effects on the sex-specific expression of CYP2C11 and CYP2C12. The effects of IGF-I were similar to those of GH. In contrast, in hypophysectomised rats IGF-I gave effects opposite to those observed after GH treatment to normal rats on the CYP3A-associated cortisol 6beta-hydroxylation. No effects of IGF-I on the steroid 5alpha-reductase activity were observed.

Animals↗
PubMed1998

Selective effects of somatostatin analogs on human drug-metabolizing enzymes.

Pharmacologic or surgical manipulation with growth hormone secretion or with the physiologic release of somatostatin and growth hormone-releasing hormone affects some rat liver enzymes, especially the sex-differentiated ones. We investigated the effects of two somatostatin analogs on several enzyme functions in six patients with carcinoid syndrome, using codeine as a probe drug. Codeine was given intravenously and its N- and O-demethylation, as well as 6-glucuronidation catalyzed by CYP3A, CYP2D6, and uridine diphosphate-glucuronosyltransferase, respectively, were studied before and during treatment with somatostatins. After 3 days of treatment with somatostatins the partial metabolic clearance of codeine by N-demethylation decreased by 21% to 64% in all patients (mean change, 44%; p < 0.05), and the clearance by O-demethylation was decreased by 20% to 69% in five of the patients (mean change in all patients, 35%; p < 0.05). In contrast, the partial clearance by 6-glucuronidation and the total systemic clearance of codeine were unchanged. Our results may be caused by the inhibition of growth hormone secretion induced by the somatostatins, inasmuch as direct metabolic interactions with these peptide drugs are improbable. The decline in CYP3A4 and CYP2D6 activity might have clinical implications when substrates of these enzymes with low therapeutic indices are combined with somatostatin analogs. Because the formation of morphine from codeine was altered, the analgesic effect of this drug may be reduced during concomitant treatment with somatostatins.

Adult↗
PubMed1998

[A new MR-(and CT-) compatible bone biopsy system: first clinical results].

PURPOSE: To describe the development and clinical evaluation of a new, hand-powered or alternatively motor-driven, MRI and CT compatible percutaneous bone biopsy system. MATERIALS AND METHODS: A new coaxial drill system (Cook Europe A/S) was designed for percutaneous, MR-guided bone biopsies and powered either by hand or an optional motor (10-250 rotations/minute using 6 bar [88.2 PSI] compressed air). The system has been used in 23 patients. Fourteen procedures were performed in a 1.5 T MR scanner (Philips-Gyroscan ACS-NT) which has an attached C-arm (Philips-BV 212-Angio) in case fluoroscopy is required, and 9 procedures in a CT scanner (Siemens-Somatom Plus). RESULTS: Driven by hand or by the pneumatic motor unit, the system achieved safe and accurate MR-guided access to all of the lesions and was even able to penetrate osteosclerotic lesions. MR- or CT-guided percutaneous biopsy yielded a correct diagnosis in all but 5 cases. No procedural complications occurred. CONCLUSION: MR-guided percutaneous bone biopsy performed with the new coaxial drill system was found to be safe and reliable, and suitable for obtaining histological specimens from skeletal lesions even when covered with thick cortical or sclerotic bone.

Biopsy↗
PubMed1997

Toward understanding insulin fibrillation.

Formation of insulin fibrils is a physical process by which partially unfolded insulin molecules interact with each other to form linear aggregates. Shielding of hydrophobic domains is the main driving force for this process, but formation of intermolecular beta-sheet may further stabilize the fibrillar structure. Conformational displacement of the B-chain C-terminal with exposure of nonpolar, aliphatic core residues, including A2, A3, B11, and B15, plays a crucial role in the fibrillation process. Recent crystal analyses and molecular modeling studies have suggested that when insulin fibrillates this exposed domain interacts with a hydrophobic surface domain formed by the aliphatic residues A13, B6, B14, B17, and B18, normally buried when three insulin dimers form a hexamer. In rabbit immunization experiments, insulin fibrils did not elicit an increased immune response with respect to formation of IgG insulin antibodies when compared with native insulin. In contrast, the IgE response increased with increasing content of insulin in fibrillar form. Strategies and practical approaches to prevent insulin from forming fibrils are reviewed. Stabilization of the insulin hexameric structure and blockage of hydrophobic interfaces by addition of surfactants are the most effective means of counteracting insulin fibrillation.

Animals↗