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Biomedical subjects

J Persson

Publications and source records attributed to J Persson.

At least 55 records · Page 3Linked to original sources
PubMed1997

Intraindividual and interindividual variability in the disposition of the local anesthetic ropivacaine in healthy subjects.

To predict the risk of adverse reactions to local anaesthetics used in clinical practice, it is crucial to know whether any nonlinearity exists in their pharmacokinetics. The disposition of ropivacaine, a new local anesthetic agent, was evaluated in healthy subjects on the basis of plasma levels in the concentration range obtained after regional anaesthesia. Three intravenous doses of ropivacaine hydrochloride (20, 40, and 80 mg) were given in a double-blind, randomized, complete crossover design. Analysis of variance was used to assess the importance of intra- versus interindividual variability in the basic pharmacokinetics. The mean plasma clearance (400 ml/min), volume of distribution at steady state (40 l), and terminal half-life (1.7 h) were similar, irrespective of dose. The intersubject variability for these parameters was higher than the intrasubject variability. A slight increase in free fraction (15%) with increasing dose might indicate that the lower limit for saturation of protein binding may be reached at the higher plasma levels. One subject (80 mg) reported numbness of the lower lip 2 min after the end of the infusion, which may be a sign of systemic CNS toxicity. The total and free plasma concentration was extrapolated to 1.7 and 0.08 mg/l, respectively.

Adult↗
PubMed1997

Assistive technology selection: a study of participation of users with rheumatoid arthritis.

A new program based on improved user participation for the selection of assistive devices was implemented and its effectiveness and efficiency assessed. The intervention was compared with traditional routines. The study population comprised persons with rheumatoid arthritis who lived in two communities in Sweden. The selection process yielded increased user participation, user satisfaction, an increased number of prescriptions, and consequently also higher costs. The outcome measures showed more vague improvements. No improvement in functional ability was found regarding pain and difficulty with daily activities in the two study groups, but an increased use of assistive devices was found among women below 64 years in the intervention group (p = 0.001). Women below 64 years in the intervention group rated an improved health-related quality of life regarding both the total score (p = 0.017) and the underlying dimensions of physical function (p = 0.012). Even though the intervention yielded positive results on process-variables as increased user participation and an increased number of prescribed assistive devices, only women below 64 years showed an increased use of assistive devices in daily activities and an improved health related quality of life.

Activities of Daily Living↗
PubMed1997

Mucosal bacterial growth in the upper gastrointestinal tract in alcoholics (heavy drinkers).

BACKGROUND/AIMS: Mucosal adherent bacterial flora in chronic alcoholics was studied and compared to a control group referred for upper endoscopy, mainly for dyspepsia. METHODS: 22 alcoholics, admitted to hospital for detoxification, were examined using upper gastrointestinal endoscopy. Gastric and duodenal biopsies were taken for tissue pathology, quantitative and qualitative anaerobic and aerobic bacteriological culture and for culture of Helicobacter pylori (antral biopsies). 12 nonalcoholics, admitted for upper endoscopy mainly for dyspepsia, were chosen as a control group. Seven of these had used gastric acid inhibitors. RESULTS: Gastrointestinal symptoms were common among alcoholics: 20/22 (90%) had diarrhea, nausea and/or abdominal pain. There were signs of gastritis by endoscopy in 64% of the alcoholics and in 58% of the controls. Tissue pathology, however, showed active chronic antral gastritis in 27% of the alcoholics and in 42% of the controls. H. pylori were isolated in 7/22 of the alcoholics and in 4/12 of the controls, which corresponds to the mean prevalence for these age groups in Sweden. Significantly more bacteria, dominated by gram-positive aerobic cocci, were present in the gastric biopsies of alcoholics than in those of controls (mean of 2.9 x 10(6)/g material versus 4.4 x 10(5), p < 0.05). There were 2.6 times more bacteria in the duodenal biopsies of alcoholics than in those of the controls (p > 0.05, NS). Bacterial overgrowth (defined as >2 x 10(3) organisms/g material) was found in the stomach in 20/22 (90%) alcoholics and in 6/12 (50%) controls (p < 0.01). CONCLUSION: Alcoholics have an increased frequency of bacterial overgrowth in the upper gastrointestinal tract. This may contribute to the common gastrointestinal symptoms.

Adult↗
PubMed1997

Surgical correction of dentofacial anomalies: an evaluation of two patient groups with the aid of a a questionnaire.

The study is based on a questionnaire answered by 273 patients with dentofacial anomalies who underwent surgery between 1988-1992 in Boden and Jönköping. The questions concerned how the patients experienced their circumstances before, during, and after treatment, and the care they received. The purpose of the study was to investigate the patients' experience of the treatment, and, thereby, evaluate the treatment team's care in order to improve it. The patients responded mainly positively about the treatment they received, despite it having been both long and trying. The main problems for patients with dentofacial anomalies are functional and aesthetic. Patients were not particularly bothered by the length of time the treatment took or that the results had not been predicted with certainty prior to the treatment. The treatment resulted in a radical change for the better in both appearance and the functional and occlusal aspects of the masticatory system. The questionnaire worked well as an instrument for use by the treatment teams to survey the results of their efforts from the point of view of their patients.

Adolescent↗
PubMed1996

Progression of atherosclerosis in middle-aged men: effects of multifactorial intervention.

OBJECTIVE: To determine the effect of multifactorial intervention against cardiovascular risk factors on ultrasound-determined progression of atherosclerosis in healthy middle-aged men. DESIGN: One hundred and forty-nine healthy middle-aged men were assigned to an intervention group (IG) or a control group (CG). SUBJECTS: The participants had moderately increased risk-factor scores for cardiovascular disease. They were recruited from a health screening programme at the Preventive Medicine Section, Department of Medicine, Lund University, University Hospital, Malmö. During the study period, 32 of the subjects were lost to follow-up, leaving 59 in the IG and 58 in the CG. INTERVENTION: The IG subjects underwent multifactorial intervention for 2 years, the goal being to help them stop smoking and to reduce their blood lipids and blood pressure. MAIN OUTCOME MEASURES: Intima-media thickness and plaque score in the right carotid artery were ultrasonographically determined initially and after 2 years. Blood lipids and blood pressure were measured at the same time, and in the IG also after 3, 6, 12 and 18 months after entry into the study. RESULTS: At the entry into the study, there were no significant differences in major risk factors or ultrasound variables between IG and CG. Blood lipids and smoking decreased significantly during the 2 years of intervention in the IG, whilst these factors remained unchanged in the CG. Intima-media thickness and plaque scores increased significantly in both groups. CONCLUSIONS: No effects on ultrasound variables could be detected after 2 years of multifactorial intervention. A more aggressive intervention programme, possibly more dependent on pharmacological treatment, may be required to obtain reduced progression or regression of atherosclerosis.

Adult↗
PubMed1996

Assistive technologies in stroke rehabilitation from a user perspective.

The purpose of the study was to provide knowledge, from a user perspective, about the selection process for assistive devices. Thirty-eight persons who had suffered stroke were interviewed about their assistive devices, approximately one year after stroke. It was found that the patients had little influence on the choice of assistive devices and that the maintenance and follow-up routines varied among patients. In some cases follow-up was not done at all. Despite these deficits, the patients used their assistive devices as intended.

Activities of Daily Living↗
PubMed1995

Central nervous system effects of subdissociative doses of (S)-ketamine are related to plasma and brain concentrations measured with positron emission tomography in healthy volunteers.

Plasma concentrations, maximum regional brain concentrations, and specific regional binding in the brain after administration of 0, 0.1, and 0.2 mg/kg doses of (S)-ketamine were measured in a randomized, double-blind, crossover study in five volunteers and were related to induced effects such as analgesia, amnesia, and mood changes. Specific binding in the brain was assessed by simultaneous administration of (S)-[N-methyl-11C]ketamine quantified by positron emission tomography. High radioactivities in the brain corresponded to regional distribution of N-methyl-D-aspartate receptor complexes. A significant and dose-dependent reduction of binding was measured as a result of displacement of (S)-[N-methyl-11C]ketamine. Memory impairment and psychotomimetic effects were related to dose, plasma concentration 4 minutes after administration, and decreased regional binding of (S)-ketamine in the brain and were consistently seen at plasma and maximum regional brain (S)-ketamine concentrations higher than 70 and 500 ng/ml, respectively. The magnitude of specific binding of (S)-ketamine, measured with positron emission tomography, can be related directly to drug effects.

Adult↗
PubMed1995

Organotellurium compounds as efficient retarders of lipid peroxidation in methanol.

Diaryl tellurides were found efficiently to retard azo-initiated lipid peroxidation of linoleic acid in methanol. The most efficient compounds, 31 and 39, contained one and two hydroxyl groups, respectively, in the para positions and methyl groups in all four positions ortho to tellurium. As determined by the values of n.kinh, these materials were as effective retarders of lipid peroxidation as vitamin E. Contrary to the conventional antioxidants examined, diaryl tellurides were found to inhibit peroxidation for long times, seemingly with an autocatalytic mechanism. Diaryl tellurides were found to be partially oxidized during the peroxidation. The reduction of tellurium (IV) compounds to the divalent state during the conditions of the experiment is discussed. The reactivity of some diaryl chalcogenides toward 2,2-diphenyl-1-picrylhydrazyl (DPPH) in methanol was studied. All compounds investigated were less reactive than vitamin E. One of the most active organotellurium compounds, bis(4-aminophenyl) telluride, reacted considerably faster with DPPH than the corresponding selenide or sulfide. It was concluded that mechanisms involving both hydrogen atom transfer and electron transfer were operative in the reaction of organotellurides with DPPH.

Antioxidants↗
PubMed1995

Technology and disability. Assessment needs and potential.

In assessing technologies for disabled people, the aims of habilitative or rehabilitative interventions, the concepts of disability and handicap, and the potential of existing and emerging technologies in various social arenas, as well as the structure of service delivery systems, are of importance. A discussion of these issues in the light of previous work on cost and effectiveness in the field is given.

Persons with Disabilities↗
PubMed1995

Assessment of rehabilitation technologies in stroke. Outcomes and costs.

Initial functional ability (Barthel Index, mean 57) was found to be an important predictor of functional ability 1 year after stroke (mean 80) and for costs during the period. On average the total cost for a stroke patient was about SEK 200,000; the main expense, accommodation, averaged about SEK 140,000, while assistive devices amounted to SEK 2,600. Those who use assistive devices, although having achieved a high functional ability, perceive and rate their life situation (Nottingham Health Profile) considerably more impaired than those without assistive devices.

Aged↗
PubMed1995

The cost of the Swedish handicap service system. Implications for technology assessment.

The total cost of the Swedish handicap system is estimated at US $10.7 billion for 1989. The cost is distributed across different authorities with separate legal and financial responsibility. The concept of technology must be extended to include consideration of both the resources spent and benefits gained in the public sector and the magnitude and distribution of transfer payments from social insurance to fulfill its function in handicap policy decision making.

Costs and Cost Analysis↗
PubMed1995

Cost-utility analysis of assistive technologies in the European Commission's TIDE Program. Technology Initiative for Disabled and Elderly People.

Socioeconomic evaluation is an issue dealt with in the European Commission's research program TIDE. The principles of cost-utility analysis have been examined for usability in the assessment of rehabilitative technologies. A case study, the choice of a type of wheelchair, is described to demonstrate how estimates of utility can be derived and how cost-utility ratios can be used to guide decision making.

Aged↗
PubMed1994

An electron microscope and electron diffraction study of the effect of calcofluor and congo red on the biosynthesis of chitin in vitro.

The structure of chitin made in vitro by chitin synthetase was studied by electron microscopy and electron diffraction. Two different forms of chitin synthetase from the fungus Mucor rouxii were tested: chitosomes and 16 S particles. The long chitin fibrils produced by chitosomes had a high degree of crystallinity as revealed by electron diffraction. Specimen regions made of largely parallel microfibril bundles produced distinct fiber diagrams, an indication that the chitin chains were aligned along the fibril axis. Microdiffractometry of the shorter chitin crystals synthesized by 16 S particles also showed a similar alignment of chitin chains. Calcofluor and Congo red were powerful inhibitors of chitin synthetase and had profound effects on the color, macroscopic texture, electron microscopic morphology, and crystal structure of the biosynthesized chitin. Chitin made in the presence of Congo red had a bright red color; the one made in the presence of Calcofluor was strongly fluorescent and had a distinctly blue hue when illuminated by daylight. The dyes were tightly bound to the chitin and could not be removed by washing with water or ethanol. At low dye concentration, a mixture of two kinds of crystals was produced by 16 S particles: some were of the same dimensions as those made in the absence of dyes, but others were much thinner. At high dye concentration, there were only thin crystals. With increasing concentrations of Calcofluor or Congo red, the typical electron diffraction reflections of alpha-chitin, particularly the strong equatorial band at 0.466 nm became fainter and a new additional reflection centered at 0.40 nm arose as the dominant feature of the patterns. We regard the gel-like material, synthesized at highly inhibitory dye concentrations, as an apposition complex where the dye does not form part of the crystal structure of chitin and the bulk of the complex consists of molecular stacks of dye associated with nascent chitin chains or narrow chitin microfibrils.

Benzenesulfonates↗