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Biomedical subjects

L Jonsson

Publications and source records attributed to L Jonsson.

At least 19 recordsLinked to original sources
PubMed2006

An estimate of the worldwide prevalence and direct costs of dementia in 2003.

Dementia disorders are today considered to be a major driver of costs in health care and social systems and worrying estimates of future dementia prevalence have been presented. It is of great interest for policy makers to have an estimate of dementia disorders' contribution to global social and health care costs, particularly in light of the demographic prognoses. The worldwide costs of dementia were estimated from prevalence figures for different regions, and cost-of-illness studies from key countries using a model based on the relationship between direct costs of care per demented and the gross domestic product per capita in each country. The worldwide direct costs for dementia in 2003 are estimated at 156 billion USD in the main scenario based on a worldwide prevalence of 27.7 million demented persons (sensitivity analysis: 129-159 billion USD). Ninety-two percent of the costs are found in the advanced economies with 38% of the prevalence. Although there are several sources of uncertainty, it is obvious that the worldwide costs are substantial and the expected increase in elderly people in the developing countries presents a great challenge.

Cost of Illness↗
PubMed2005

Association between allergic rhinitis and hospital resource use among asthmatic children in Norway.

BACKGROUND: Preliminary evidence suggests that inadequately controlled allergic rhinitis in asthmatic patients can contribute towards increased asthma exacerbations and poorer symptom control, which may increase medical resource use. The objective of this study was therefore to assess the effect of concomitant allergic rhinitis on asthma-related hospital resource utilization among children below 15 years of age with asthma in Norway. METHODS: A population-based retrospective cohort study of children (aged 0-14 years) with asthma was conducted using data from a patient-specific public national database of hospital admissions during a 2-year period, 1998-1999. Multivariate linear regression, adjusting for risk factors including age, gender, year of admission, urban/rural residence and severity of asthma episode, estimated the association between allergic rhinitis and total hospital days. A multivariate Cox proportional-hazards model estimated relative hazard of readmission according to concomitant allergic rhinitis status. RESULTS: Among 2961 asthmatic children under 15 years of age with at least one asthma-related hospital admission over a 2-year period, 795 (26.8%) had a recorded history of allergic rhinitis. Asthmatic children with allergic rhinitis had a 1.72-times greater hazard of asthma-related readmissions than asthmatic children without allergic rhinitis. Multivariate analysis revealed that history of concomitant allergic rhinitis was a significant predictor of increased number of hospital days per year (least-squares mean difference 0.23 days, P < 0.05). CONCLUSIONS: Concomitant allergic rhinitis in asthmatic children was associated with increased likelihood of asthma-related hospital readmissions and greater total hospital days.

Adolescent↗
PubMed2004

Serotypes and clinical manifestations of invasive group B streptococcal infections in western Sweden 1998-2001.

This study monitored the serotypes of Streptococcus agalactiae (group B streptococcus; GBS) isolated from invasive infections in western Sweden and investigated possible relationships between serotype, age and clinical manifestations. Invasive GBS isolates were collected prospectively during 1998-2001 at six laboratories, covering two counties with a population of 1.8 million, and were serotyped by coagglutination. Clinical data were obtained from hospital notes. In total, 161 invasive strains (50 from neonates and infants aged < 3 months, and 111 from adults) were serotyped. The commonest serotypes from neonates and infants were serotypes III (60%), V (22%) and Ia (10%), and from adults were serotypes V (42%) and III (25%). Serotype V had doubled in frequency among both children and adults compared to a previous study from the same area in 1988-1997. Most (80%) of the adults had an underlying medical condition. No relationship was found between serotype and clinical manifestations. However, the study demonstrated the importance of active surveillance of GBS serotypes and the difficulties of formulating a multivalent polysaccharide conjugate vaccine against GBS.

Adolescent↗
PubMed2004

Denitrification rate and carbon source consumption in full-scale wastewater filtration.

In response to new demands for increased removal of nitrogen and phosphorus, the Henriksdal and Bromma treatment plants, with hydraulic loads of 283,000 and 148,000 m3/d, respectively, built filtration steps as a final process step in the plants. The denitrification rates in a full-scale and in a pilot plant filter are calculated to 13.1 and 21.3 g (NO3+NO2)-N/(m3 x h), respectively, in the total filter bed after 2.5-24.2 and 16.0-28.0 h of operational time, and 6.4 and 18.7 g (NO3+NO2)-N/(m3 x h), respectively, after 1.0 and 0.1-0.9 h of operational time. In composite samples, the denitrification rate in the total filter bed is 10-20 g (NO3+NO2)-N/(m3 x h) in the full-scale filter. The average values for k = deltaCODf/deltaC(T) are 1.6 and around 3 in the total filter bed in steady state and in the beginning of the experiments, respectively, both in the full-scale and in the pilot plant study. The carbon source costs for reducing the concentration of nitrate nitrogen in the Bromma plant from 12 to 8 mg/l in the effluent are 117,400 EUR and 147,400 EUR with methanol and ethanol, respectively, as a carbon source.

Acetates↗
PubMed2003

Evaluation of small wastewater treatment systems.

Different technologies for the treatment of wastewater from single houses have been evaluated by performing measurements at 14 treatment plants installed at different one-family houses located 35 km south-west of Stockholm. The technologies tested were selected in order to deliver high removal efficiencies with respect to organic matter, nitrogen and phosphorus. They also had to fulfil requirements concerning robustness, nutrient recycling, use of natural resources, economy, user-friendliness and hygiene. The systems can be divided into package plants, urine separating systems, blackwater separating systems and chemical precipitation as a supplement to sand filter beds. All of the systems were able to remove more than 90% of phosphorus and more than 90% of organic matter. Concerning package plants, it is necessary to have reliable dosing equipment and frequent checks to achieve long-term phosphorus removal. The source separation systems require well-informed and motivated users to achieve desirable removal efficiency. Sorting systems seem to be superior with respect to nitrogen removal, even though some of the package plants gave nitrogen removal above 50% during long periods of operation.

Biofilms↗
PubMed2002

Food conversion is transiently affected during 4-week chronic administration of melanocortin agonist and antagonist in rats.

The central melanocortin system is involved in the regulation of food intake and body weight. In this study, we investigated the effect of a 4-week intracerebroventricular infusion of the melanocortin receptor agonist MT-II and the selective melanocortin-4 receptor antagonist HS024 on food intake and body weight homeostasis. The MT-II-treated rats ate less and lost considerably more weight than the control rats during the first week of treatment. During the second and third week, they gained weight and, by the end of the treatment period, the weight gain was similar to that of the control rats. The HS024 treatment caused hyperphagia and development of obesity during the entire period. Extensive accumulations of fat and a sixfold increase in leptin levels were observed in the HS024-treated rats, as compared with controls, after the 4-week period. Food conversion ratio, defined as body weight increase relative to weight of ingested food, was clearly increased in the HS024-treated rats, while it was lowered in the MT-II-treated rats compared with controls. The effect on food conversion ratio was transient, being greatest for both experimental groups during the first week and it was then attenuated to reach the level of controls at the end of the study. The results suggest that long-term injection of exogenous melanocortin receptor active substances may have an important transient effect on food conversion.

Analysis of Variance↗
PubMed2001

Melanocortin receptor agonist transiently increases oxygen consumption in rats.

Acute injections of melanocortin (MC) agonist and antagonist are highly effective in reducing or increasing food take, respectively. Much less is known about how injection of MC receptor active substances affects metabolism, in particular during long term administration. Here we investigated the effect of 8 days continuous i.c.v. infusion of either MC receptor agonist MTII or the selective MC4 receptor antagonist HS024 on oxygen consumption, food intake and body weight in rats. We observed significant increase in oxygen consumption 2 days after the start of the MTII infusion. However, this increase had disappeared by day 4 of the study. No difference was observed in the oxygen consumption after injection of HS024. MTII substantially decreased the food intake during the first days, but then the feeding recovered and the body weight stabilised at a new level. The immediate effect of the MC receptor agonist on both food intake and metabolism was thus transient, even though the weight loss was maintained. The HS024 treated rats were hyperphagic throughout the test period, continuously gaining weight, resulting in increased fat pads and high leptin levels. This is the first study that describes long term effects of MC receptor agonist and antagonist on metabolism and energy balance.

Animals↗
PubMed2001

Sterol composition and growth of transgenic tobacco plants expressing type-1 and type-2 sterol methyltransferases.

Transgenic tobacco (Nicotiana tabacum L.) plants with altered sterol composition were generated by transformation with plant cDNAs encoding type-1 and type-2 sterol methyltransferases (SMTs; EC 2.1.1.41). For both SMT1 and SMT2 transformants, the transformation was associated with a reduction in the level of cholesterol, a non-alkylated sterol. In SMT1 transformants a corresponding increase of alkylated sterols, mainly 24-methyl cholesterol, was observed. On the other hand, in SMT2 transformants the level of 24-methyl cholesterol was reduced, whereas the level of sitosterol was raised. No appreciable alteration of total sterol content was observed for either genotype. The general phenotype of transformants was similar to that of controls, although SMT2 transformants displayed a reduced height at anthesis. The results show that plant sterol composition can be altered by transformation with an SMT1 cDNA without adverse effects on growth and development, and provide evidence, in planta, that SMT1 acts at the initial step in sterol alkylation.

Arabidopsis↗
PubMed2000

Bloch oscillations in the presence of plasmons and phonons

The coupling between Bloch oscillating electrons and longitudinal optical phonons in a superlattice leads to resonant phonon excitation but no gap in the Bloch-phonon spectrum. In addition, we predict a sharp transition from plasma to Bloch oscillations at nu(B) = 2nu(P). From a microscopic description with phenomenological dampings, we numerically map out the behavior of coupled Bloch-plasmon-phonon modes for a wide range of parameters, and mimic experimental conditions. Our results are in good agreement with recent experiments by Dekorsy et al. [Phys. Rev. Lett. 85, 1080 (2000)].

Journal Article↗
PubMed2000

Electroneurographic facial muscle pattern in Bell's palsy.

To study the electroneurographic facial muscle pattern in Bell's palsy over time, electroneurographic recordings in the frontalis, orbicularis oculi, nasalis, and mentalis muscle regions were performed early (mean, day 11) and 1 and 3 months after the onset of the condition in 30 consecutive patients. The correlation between facial muscle electroneurographic recordings over time was also calculated. An additional aim was to assess whether further prognostic information could be obtained by electroneurographic recordings in more than one facial region. The recovery pattern was similar in all 4 facial regions. Initially, the correlation between the facial recordings was weak (r = 0.20-0.27), but it was improved at follow-up examinations (r = 0.33-0.65). Favorable outcome in 23 of 24 patients (96%) could have been predicted by the initial nasalis and/or mentalis recordings. The gap between patients with favorable outcome and patients with unfavorable outcome increased when the average electroneurography values were calculated from 1, 2, and 4 muscle recordings (4%, 8%, and 15%, respectively). Our results indicate that in Bell's palsy, electroneurographic examination of more than one facial muscle region may add prognostic information and that the degree of degeneration is initially different in the nerve branches.

Action Potentials↗
PubMed2000

Diversity and abundance of resupinate thelephoroid fungi as ectomycorrhizal symbionts in Swedish boreal forests.

Resupinate thelephoroid fungi (hereafter called tomentelloid fungi) have a world-wide distribution and comprise approximately 70 basidiomycete species with inconspicuous, resupinate sporocarps. It is only recently that their ability to form ectomycorrhizas (EM) has been realized, so their distribution, abundance and significance as mycobionts in forest ecosystems is still largely unexplored. In order to provide baseline data for future ecological studies of tomentelloid fungi, we explored their presence and abundance in nine Swedish boreal forests in which the EM communities had been analysed. Phylogenetic analyses were used to compare the internal transcribed spacer of nuclear ribosomal DNA (ITS rDNA) sequence data obtained from mycobionts on single ectomycorrhizal tips with that obtained from sporocarps of identified tomentelloid fungi. Five species of Tomentella and one species of Pseudotomentella were identified as ectomycorrhizal fungi. The symbiotic nature of Tomentella bryophila, T. stuposa, T. badia and T. atramentaria is demonstrated for the first time. T. stuposa and Pseudotomentella tristis were the most commonly encountered tomentelloid fungi, with the other species, including T. sublilacina, only being recorded from single stands. Overall, tomentelloid fungi were found in five of the studies, colonizing between 1 and 8% of the mycorrhizal root tips. Two of the five sites supported several tomentelloid species. Tomentelloid fungi appear to be relatively common ectomycorrhizal symbionts with a wide distribution in Swedish coniferous forests. The results are in accordance with accumulating data that fungal species which lack conspicuous sporocarps may be of considerable importance in EM communities.

DNA, Ribosomal↗
PubMed1999

Long term orexigenic effect of a novel melanocortin 4 receptor selective antagonist.

1. We designed and synthesized several novel cyclic MSH analogues and tested their affinities for cells expressing the MC1, MC3, MC4 and MC5 receptors. 2. One of the substances HS028 (cyclic [AcCys11, dichloro-D-phenylalanine14, Cys18, Asp-NH2(22)]-beta-MSH11-22) showed high affinity (Ki of 0.95nM) and high (80 fold) MC4 receptor selectivity over the MC3 receptor. HS028 thus shows both higher affinity and higher selectivity for the MC4 receptor compared to the earlier first described MC4 receptor selective substance HS014. 3. HS028 antagonised a alpha-MSH induced increase in cyclic AMP production in transfected cells expressing the MC3 and MC4 receptors, whereas it seemed to be a partial agonist for the MC1 and MC5 receptors. 4. Chronic intracerebroventricularly (i.c.v.) administration of HS028 by osmotic minipumps significantly increased both food intake and body weight in a dose dependent manner without tachyphylaxis for a period of 7 days. 5. This is the first report demonstrating that an MC4 receptor antagonist can increase food intake and body weight during chronic administration providing further evidence that the MC4 receptor is an important mediator of long term weight homeostasis.

Animals↗
PubMed1998

beta-cell-specific inactivation of the mouse Ipf1/Pdx1 gene results in loss of the beta-cell phenotype and maturity onset diabetes.

To study the late beta-cell-specific function of the homeodomain protein IPF1/PDX1 we have generated mice in which the Ipf1/Pdx1 gene has been disrupted specifically in beta cells. These mice develop diabetes with age, and we show that IPF1/PDX1 is required for maintaining the beta cell identity by positively regulating insulin and islet amyloid polypeptide expression and by repressing glucagon expression. We also provide evidence that IPF1/PDX1 regulates the expression of Glut2 in a dosage-dependent manner suggesting that lowered IPF1/PDX1 activity may contribute to the development of type II diabetes by causing impaired expression of both Glut2 and insulin.

Amyloid↗
PubMed1998

House-Brackmann and Yanagihara grading scores in relation to electroneurographic results in the time course of Bell's palsy.

The results of House Brackmann and Yanagihara grading were compared with electroneurographic (ENoG) data in 30 consecutive patients with Bell's palsy. The examinations were made on mean days 11, 36 and 99. Twenty-four patients had a favourable outcome (Yanagihara > or = 36 at three months). Based on our observations, 23 (96%) of these could have been predicted by ENoG, 18 (75%) by Yanagihara grading and 6 (25%) by House Brackmann grading. Initially, the relative House Brackmann scores showed a slightly milder palsy than the Yanagihara scores, but in the follow-up period the gradings were almost identical. The mild palsies, defined on the initial ENoG results, initially demonstrated relatively less nerve dysfunction on ENoG than the clinical grading; by the first follow-up, the ENoG and clinical grading had both returned to normal. The intermediate palsies had almost the same initial relative clinical and ENoG values, but at the first follow-up (mean day 36), the facial function had returned to normal despite abnormally reduced, but improved, ENoG values. In the severely affected patients, the follow-up studies showed an improved clinical function but ENoG values still demonstrated a high degree of degeneration (slightly improved at second follow-up). In this study, patients with a favourable outcome were best predicted with ENoG. Clinical identification of these patients was more accurate with Yanagihara than with House Brackmann. Furthermore, in all three groups a clinical improvement, due to the release of neurapraxia, was noted at the first follow-up. The slow ENoG improvement noted at follow-up was probably due to nerve regeneration by collateral sprouting. Based on the time course of our ENoG findings, it appears that patients with a high degree of degeneration at both the initial examination and first follow-up have a poorer prognosis.

Adult↗
PubMed1997

Serial gadolinium-enhanced magnetic resonance imaging and assessment of facial nerve function in Bell's palsy.

Eleven patients with mild or moderate acute idiopathic peripheral facial palsy, so-called Bell's palsy, were serially examined by gadolinium-DTPA-enhanced MRI on mean days 11, 40, and 97 (third examination, n = 10) after the onset of palsy. Results of the clinical and neurophysiologic assessment of facial nerve function were compared with the gadolinium-enhanced MRI findings. Eight of the 11 patients demonstrated contrast enhancement of the facial nerve at the initial examination, but in 7 of them, the enhancement had disappeared by the time of the serial follow-up gadolinium-enhanced MRI scans. The disappearance of facial nerve enhancement was found to be related to clinical and neurophysiologic improvements in facial nerve function during recovery from Bell's palsy. The three patients whose scans were negative at the initial gadolinium-enhanced MRI examination had the same clinical severity of palsy, but initially they had milder neurophysiologic involvement than those who demonstrated enhancement; these three patients did not exhibit enhancement at serial follow-up scans. These findings indicate that the presence of enhancement at the initial MRI scan is not necessarily indicative of a poor prognosis for recovery.

Acute Disease↗