Search PubMed⌕ Search

Biomedical subjects

Leif Johansson

Publications and source records attributed to Leif Johansson.

13 recordsLinked to original sources
PubMed2006

Do topical nasal decongestants affect polyps?

CONCLUSIONS: The hypothesis that decongestants reduce the size of nasal polyps could not be verified. Decongestion is therefore recommended prior to nasal endoscopy, especially in polyp diagnosis, as it does not artificially change the size of the polyps. OBJECTIVE: The role of nasal decongestants in nasal stuffiness is well established and their action is well known. Decongestants are also used prior to nasal endoscopy to achieve a better view of the nasal cavity in order to diagnose polyps. The question is whether this decongestion invalidates the estimation of polyp size in clinical and scientific practice. The aim of this study was to evaluate possible effects of topical decongestants on polyp extension in patients with nasal polyposis. MATERIAL AND METHODS: The effect of the decongestants nafazoline and epinephrine on nasal polyp size was assessed by means of a double-blind, placebo-controlled randomized study. A sensitive endoscopic scoring system, lateral imaging, was used to assess the size and extension of the nasal polyps. RESULTS: No significant effect of decongestion on polyp size could be found for either treatment.

Administration, Intranasal↗
PubMed2006

Multiple pressure-volume loops recorded with sinusoidal low flow in a porcine acute respiratory distress syndrome model.

OBJECTIVES: To develop a method for automatic recording of multiple dynamic elastic pressure-volume (P(el)/V) loops. To analyse the relationship between multiple dynamic P(el)/V loops and static P(el)/V loops in a porcine model of acute lung injury/acute respiratory distress syndrome (ALI/ARDS). To test the hypothesis that increasing lung collapse and re-expansion with decreasing positive end expiratory pressure (PEEP) can be characterized by hysteresis of the P(el)/V loops. MATERIAL AND INTERVENTIONS: In eight anaesthetized and paralysed pigs, ALI/ARDS was induced by inhalation of dioctyl sodium sulfosuccinate and large tidal volume ventilation. MEASUREMENTS AND RESULTS: The physiological and histopathological findings indicated a status mimicking an early stage of ALI/ARDS. Automatically, a series of dynamic P(el)/V loops from different PEEP levels were recorded with the sinusoidal flow modulation method using a computer-controlled ventilator. During expiration, resistance increased more than twofold. For each step of lower starting pressure, the inspiratory limb was displaced towards lower volume indicating derecruitment. Recruitment occurred between 20 and 40 cm H(2)O. The expiratory curves, all starting from 50 cm H(2)O, overlapped. Hysteresis increased significantly in loops recorded from lower PEEP levels. Viscoelasticity explained differences between static and dynamic P(el)/V loops. CONCLUSIONS: Automated multiple P(el)/V loop determination is feasible and provides comprehensive information on lung derecruitment and recruitment. It requires determination of volume dependence of expiratory resistance. An expiratory curve serves as a reference to inspiratory curves and provides information about hysteresis.

Airway Resistance↗
PubMed2005

Panmixia in the European eel: a matter of time...

The European eel (Anguilla anguilla L.) has been a prime example of the panmixia paradigm because of its extraordinary adaptation to the North Atlantic gyral system, semelparous spawning in the Sargasso Sea and long trans-oceanic migration. Recently, this view was challenged by the suggestion of a genetic structure characterized by an isolation-by-distance (IBD) pattern. This is only likely if spawning subpopulations are spatially and/or temporally separated, followed by non-random larval dispersal. A limitation of previous genetic work on eels is the lack of replication over time to test for temporal stability of genetic structure. Here, we hypothesize that temporal genetic variation plays a significant role in explaining the spatial structure reported earlier for this species. We tested this by increasing the texture of geographical sampling and by including temporal replicates. Overall genetic differentiation among samples was low, highly significant and comparable with earlier studies (FST = 0.0014; p < 0.01). On the other hand, and in sharp contrast with current understandings, hierarchical analyses revealed no significant inter-location genetic heterogeneity and hence no IBD. Instead, genetic variation among temporal samples within sites clearly exceeded the geographical component. Our results provide support for the panmixia hypothesis and emphasize the importance of temporal replication when assessing population structure of marine fish species.

Anguilla↗
PubMed2005

Can pulsed ultrasound increase tissue damage during ischemia? A study of the effects of ultrasound on infarcted and non-infarcted myocardium in anesthetized pigs.

BACKGROUND: The same mechanisms by which ultrasound enhances thrombolysis are described in connection with non-beneficial effects of ultrasound. The present safety study was therefore designed to explore effects of beneficial ultrasound characteristics on the infarcted and non-infarcted myocardium. METHODS: In an open chest porcine model (n = 17), myocardial infarction was induced by ligating a coronary diagonal branch. Pulsed ultrasound of frequency 1 MHz and intensity 0.1 W/cm2 (ISATA) was applied during one hour to both infarcted and non-infarcted myocardial tissue. These ultrasound characteristics are similar to those used in studies of ultrasound enhanced thrombolysis. Using blinded assessment technique, myocardial damage was rated according to histopathological criteria. RESULTS: Infarcted myocardium exhibited a significant increase in damage score compared to non-infarcted myocardium: 6.2 +/- 2.0 vs. 4.3 +/- 1.5 (mean +/- standard deviation), (p = 0.004). In the infarcted myocardium, ultrasound exposure yielded a further significant increase of damage scores: 8.1 +/- 1.7 vs. 6.2 +/- 2.0 (p = 0.027). CONCLUSION: Our results suggest an instantaneous additive effect on the ischemic damage in myocardial tissue when exposed to ultrasound of stated characteristics. The ultimate damage degree remains to be clarified.

Animals↗
PubMed2005

Loss of mismatch repair protein immunostaining in colorectal adenomas from patients with hereditary nonpolyposis colorectal cancer.

Colorectal adenomas occur at younger age, at increased frequency and have a greater tendency for malignant transformation in patients with hereditary nonpolyposis colorectal cancer (HNPCC). We performed immunostaining for the mismatch repair proteins MLH1, PMS2, MSH2 and MSH6 in 35 colorectal adenomas from 26 patients with HNPCC and identified loss of immunostaining in 23/35 (0.66) adenomas. Loss of mismatch repair protein immunostaining was particularly frequent in large (>5 mm) (14/16) and proximally located (13/15) adenomas, whereas the gene mutated--MLH1 or MSH2--and the type of mutation did not seem to affect the results. We conclude that loss of mismatch repair protein immunostaining is detected at a lower rate in adenomas than in carcinomas associated with HNPCC. Adenomatous tissue can thus be used for immunostaining of mismatch repair proteins in clinical investigations of HNPCC, but whereas loss of immunostaining may pinpoint the gene affected and thereby guide mutation analysis, retained staining cannot exclude that the adenoma developed as part of the syndrome due to reduced sensitivity. However, the analysis has a greater chance of being informative if large and proximally located adenomas are selected.

Adaptor Proteins, Signal Transducing↗
PubMed2004

Histopathologic classification of lung cancer: Relevance of cytokeratin and TTF-1 immunophenotyping.

Histopathologic classification of lung carcinoma is important, as a prognostic factor and in the evaluation of treatment modalities. Although the World Health Organization classification of lung cancer is based on routine microscopy, immunohistochemistry is an important additional aspect in modern pathologic practice. This study examines whether the main histologic types of lung carcinomas are more reliably diagnosed with immunohistochemical technique using antibodies for the lung tissue-specific antigen thyroid transcription factor-1 (TTF-1) and a panel of cytokeratin (CK) antibodies. Forty-five cases of lung cancer (12 squamous cell carcinoma, 13 small cell carcinoma, 11 adenocarcinoma, 9 large cell carcinoma [LCC]/pleomorphic carcinoma) were stained with antibodies to CK CAM5.2, CK5, CK7, CK20, and TTF-1. All 45 cases were positive with CAM5.2, 16 of 45 cases with CK5, 34 of 45 cases with CK7, 4 of 45 cases with CK20, and 29 of 45 with TTF-1. Squamous cell carcinoma (epidermoid carcinoma) had the immunophenotype CK5+/TTF-1-, and at least 20% were also positive with CK7. Most nonepidermoid tumors had the "lung-specific" phenotype CK5-/TTF-1+; all small cell carcinomas had the phenotype CK5-/CK8+/TTF-1+, all adenocarcinomas CK5-/CK7+/TTF-1+ and (more than 50%) of LCC CK5-/CK7+/TTF-1+. Thus, more than 50% of LCCs were of the same phenotype as adenocarcinomas. The immunophenotypes of the main histologic types of lung carcinoma are stable and highly reproducible. However, because of considerable overlapping, immunophenotyping should not be used alone for histopathologic classification of lung cancer, but only as an adjunct to light microscopy. It is also suggested that CK5+ lung carcinomas with basaloid features should be regarded as variants of squamous cell carcinoma and not as LCC.

Biomarkers, Tumor↗
PubMed2004

Prevalence of olfactory dysfunction: the skövde population-based study.

OBJECTIVES/HYPOTHESIS: Patients with olfactory dysfunction appear repeatedly in ear, nose, and throat practices, but the prevalence of such problems in the general adult population is not known. Therefore, the objectives were to investigate the prevalence of olfactory dysfunction in an adult Swedish population and to relate dysfunction to age, gender, diabetes mellitus, nasal polyps, and smoking habits. STUDY DESIGN: Cross-sectional, population-based epidemiological study. METHODS: A random sample of 1900 adult inhabitants, who were stratified for age and gender, was drawn from the municipal population register of Skövde, Sweden. Subjects were called to clinical visits that included questions about olfaction, diabetes, and smoking habits. Examination was performed with a smell identification test and nasal endoscopy. RESULTS: In all, 1387 volunteers (73% of the sample) were investigated. The overall prevalence of olfactory dysfunction was 19.1%, composed of 13.3% with hyposmia and 5.8% with anosmia. A logistic regression analysis showed a significant relationship between impaired olfaction and aging, male gender, and nasal polyps, but not diabetes or smoking. In an analysis of a group composed entirely of individuals with anosmia, diabetes mellitus and nasal polyps were found to be risk factors, and gender and smoking were not. CONCLUSION: The sample size of the population-based study was adequate, with a good fit to the entire population, which suggests that it was representative for the Swedish population. Prevalence data for various types of olfactory dysfunction could be given with reasonable precision, and suggested risk factors analyzed. The lack of a statistically significant relationship between olfactory dysfunction and smoking may be controversial.

Aged↗
PubMed2003

Prevalence of nasal polyps in adults: the Skövde population-based study.

Patients with nasal polyps present repeatedly in otorhinolaryngology practices, but the prevalence of nasal polyps in the general population is not known. Our objective was to investigate the prevalence of nasal polyps in an adult Swedish population in relation to age, gender, asthma, and aspirin intolerance. A random sample of 1,900 inhabitants over the age of 20 years, stratified for age and gender, was drawn from the municipal population register in Skövde, Sweden, in December 2000. The subjects were called to clinical visits that included questions about rhinitis, asthma, and aspirin intolerance and examination by nasal endoscopy. In total, 1,387 volunteers (73% of the sample) were investigated. The sample size was adequate, with a good fit to the whole population. The prevalence of nasal polyps was 2.7% (95% confidence interval, 1.9-3.5), and polyps were more frequent in men (2.2 to 1), the elderly (5% at > or = 60 years of age), and asthmatics. Subjective symptoms of aspirin intolerance were not found to correlate with polyps. Nasal polyps were more common in adults than was stated by the a priori estimate. The Skövde population-based study is considered representative for the Swedish population.

Adult↗
PubMed2003

Cost effectiveness of nasal budesonide versus surgical treatment for nasal polyps.

OBJECTIVE: To conduct a cost-effectiveness study of nasal budesonide versus surgical treatment in the management of nasal polyps. DESIGN AND METHODS: A decision-tree model reflecting two different treatment strategies for nasal polyps in Sweden was developed. The first strategy was initial polypectomy, performed under three different sets of circumstances: inpatient functional endoscopic surgery, outpatient evulsion with sedation, or outpatient evulsion with local anaesthesia; all treatments were followed by intranasal treatment with budesonide (Rhinocort) 128 microg twice daily. The second strategy was initial intranasal treatment with budesonide 128 microg twice daily. PERSPECTIVE: Healthcare provider perspective. OUTCOME MEASURES AND RESULTS: After 1 month, treatment with nasal budesonide was classified as a success (82.5%) or a failure (17.5%) based on clinical study data. In cases of success, the treatment was continued, and in cases of failure, polypectomy was undertaken, followed by budesonide 128 microg twice daily. Treatments were evaluated after 4 months using prices from the Central Hospital in Skövde, Sweden. The expected reduction in cost from using initial nasal budesonide treatment compared with the different alternatives of polypectomy were 9760 Swedish kronors (SEK) for inpatient functional endoscopic surgery, SEK2747 for outpatient evulsion with sedation, and SEK672 for outpatient evulsion with anaesthesia (1998 values). Nasal budesonide 128 microg twice daily treatment for nasal polyps revealed a potential reduction in costs of 53% compared with the primary surgery approach. CONCLUSION: Initial treatment of nasal polyps with nasal budesonide provides lower costs than treatment with initial polypectomy with maintained effectiveness.

Administration, Intranasal↗
PubMed2003

Prevalence of nasal septal perforation: the Skövde population-based study.

BACKGROUND: Patients with nasal septal perforation appear from time to time in Ear, Nose, and Throat (ENT) practices, but the prevalence in a general population is not known. OBJECTIVE: The objective was to investigate the prevalence of nasal septal perforation in an adult Swedish population, and to relate septal perforation to possible risk factors, such as age, gender, diabetes mellitus, nasal polyps, and smoking. METHODS: A random sample of 1,900 inhabitants over the age of 20, stratified for age and gender, was drawn from the municipal population register in Skövde, Sweden, in December 2000. Subjects were called to clinical visits that included questions about diabetes and smoking habits. Nasal endoscopy was performed and, when a perforation was observed, the size was measured. RESULTS: In total, 1,387 volunteers (73% of the sample) were investigated. The sample size was adequate, with a good fit to the whole population. The prevalence of nasal septal perforation was 0.9% [95% CI 0.5-1.6%]. Nasal polyps was a possible risk factor, odds ratio of 11.5 [95% CI 3.0-43.5], but not age, gender, diabetes, or smoking. CONCLUSION: The prevalence of nasal septal perforation was found to be less than 1% in an adult population.

Adult↗
PubMedDate not supplied

Discovery of biomarker candidates within disease by protein profiling: principles and concepts.

Proteins and peptides present within clinical samples represent a valuable library of information regarding the ongoing processes within cells and tissues in health and disease. We have developed and validated novel technology applications that can be used to characterize the patterns of global protein expression in tissue and biofluids in either gel-based systems or by automated multidimensional nanocapillary liquid chromatography. Mass spectrophotometry platforms using MALDI MS and MS/MS or LTQ ion trap MS were capable of delivering sensitive and accurate identifications of hundreds of proteins contained in individual samples including individual forms of processing intermediates such as phospho peptides. The Systems Biology approach of integrating protein expression data with clinical data such as histopathology, clinical functional measurements, medical imaging scores, patient demographics, and clinical outcome provides a powerful tool for linking biomarker expression with biological processes that can be segmented and linked to disease presentation.

Animals↗
PubMedDate not supplied

[HER2 testing for breast cancer. Swedish laboratories can now offer a quality assured analysis of growth factor].

Between 20 and 30 per cent of all breast cancers show an overexpression of the growth factor HER2 and this implies a worse prognosis. Metastasising breast cancer that overexpress HER2 can effectively be treated with trastuzumab (Herceptin). In order to determine whether this treatment is indicated, HER2 expression must be quantified with immunohistochemical or molecular biological methods. Several factors may influence the laboratory analysis of HER2, such as choice of antibodies and probes, the reliability of the test performance itself and the performance of the pathologist(s) interpreting the test. National guidelines for HER2 testing have been published in several countries. In this article a series of quality assurance projects leading to the formulation of Swedish guidelines for HER2 testing is described. These projects have demonstrated that several Swedish pathology laboratories can reliably perform and interpret analysis of HER2 status today.

Antibodies, Monoclonal↗