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Biomedical subjects

L Larsson

Publications and source records attributed to L Larsson.

At least 37 records · Page 2Linked to original sources
PubMed2003

Interventional treatment of children with portal hypertension secondary to portal vein occlusion.

PURPOSE: To present methods and results of interventional treatment of children with portal hypertension (PH) secondary to portal vein occlusion (PVO). MATERIAL AND METHODS: Five children, four boys and one girl, 8 - 14 years old, with symptomatic PH secondary to PVO were treated. All children had one or more episodes of bleeding from oesophageal varices, enlarged spleen and thrombocytopenia. Partial embolisation of the spleen was performed in four children. Attempts to recanalize the occluded part of the portal vein were done in all children using transjugular (n = 4), transhepatic (n = 4) and transsplenic (n = 3) approaches. RESULTS: All procedures were carried out without serious complications and were followed by normalisation of the platelet count, decrease in splenic size and disappearance of bleeding. Recanalisation of the occluded portal vein with a stent was possible in one child and partial stent recanalisation was possible in another child. Transjugular intrahepatic portosystemic shunt (TIPS) with partly extrahepatic, intraperitoneal route was created in one patient. All children were scheduled for follow-up. During the observation time of 22 months (5 - 46 months), additional balloon dilation and placement of new stents were necessary in two children. CONCLUSION: Interventional procedures are valuable in the treatment of children with symptoms secondary to PVO. Treatment should be customized and scheduled follow-ups of the patients are necessary.

Adolescent↗
PubMed2003

The prevalence of frontal variant frontotemporal dementia and the frontal lobe syndrome in a population based sample of 85 year olds.

OBJECTIVES: To investigate the prevalence of the frontal lobe syndrome (FLS) and the frontal variant of frontotemporal dementia (fvFTD) in a population based sample of 85 year olds. METHODS: A representative sample of 85 year olds (n = 451) in Gothenburg, Sweden was examined with a neuropsychiatric examination and a key informant interview performed by an experienced psychiatrist. A subsample underwent computed tomography (CT) of the head. The Lund-Manchester research criteria were used as a basis for a symptom algorithm to identify individuals with FLS and fvFTD. These were diagnosed blindly to the diagnosis of dementia according to DSM-III-R. RESULTS: A total of 86 individuals (19%) fulfilled the criteria for FLS, and 14 of them fulfilled criteria for fvFTD. There were no differences between men and women. Among those with FLS, 75 (87%) fulfilled DSM-III-R criteria for other types of dementia, mainly Alzheimer's disease and vascular dementia. Among the 14 fvFTD cases, only five were demented according to DSM-III-R. Moderate to severe frontal atrophy was found in 93% of those with FLS (and in all cases with fvFTD), but also in 49% of those without FLS. FLS was found in 35% of those with moderate to severe frontal atrophy, and in 3% of those without these changes. CONCLUSIONS: The prevalence of fvFTD was 3% in 85 year olds, which is higher than previously expected in this age group. Only a minority of those with fvFTD were detected by the DSM-III-R criteria for dementia. FLS was even more common, especially in those diagnosed with a dementia disorder.

Aged↗
PubMed2002

Relationship between in vivo muscle force at different speeds of isokinetic movements and myosin isoform expression in men and women.

In an attempt to explore the relationship between force production during voluntary contractions at different speeds of isokinetic movement and the myofibrillar protein isoform expression in humans, an improved isokinetic dynamometer that corrects for gravitation, controls for acceleration and deceleration, and identifies a maximum voluntary activation was used. Muscle torque recordings were compared at the same muscle length (knee angle) and the torque was calculated as the average torque at each angle over a large knee angle range (75 degrees -25 degrees ) to reduce the influence of small torque oscillation on the calculated torque. Muscle torque at fast (240 degrees s(-1)) versus slow (30 degrees s(-1)) speeds of movement, torque normalized to muscle cross-sectional area (specific tension), and absolute torque at fast speeds of movement were measured in 34 young healthy male and female short-, middle-, and long-distance runners. The relationship between the different measures of muscle function and the expression of myosin heavy chain (MyHC) isoforms using enzyme-histochemical and electrophoretic protein separation techniques were investigated. A significant correlation between the 240 degrees s(-1) vs 30 degrees s(-1) torque ratio and the relative area of the type II fibers and type II MyHC isoforms were observed in both the men (r=0.74; P<0.001) and the women (r=0.81; P<0.05). Thus, the present results confirm a significant relationship between in vivo human muscle function and the MyHC isoform expression in the contracting muscle.

Adolescent↗
PubMed2002

Changes in hip fracture epidemiology: redistribution between ages, genders and fracture types.

After several reports of increasing hip fracture incidence some studies have suggested a trend-break. In a previous study of hip fractures we forecast a 70% increase in the total number of fractures from 1985 up to year 2000. We therefore studied the incidence trend for the last 15 years and supply a new prognosis up to year 2010. We recorded all incident hip fractures treated in the county of Ostergötland, Sweden (approximately 400,000 inhabitants) 1982-96. A total of 11,517 hip fractures in men and women aged 50 years and above were included in the study after cross-validation between a computerized register of radiologic investigations and the hospital records. The projected number of fractures up to year 2010 was estimated by a Poisson regression model, considering both age and year of fracture in every single year 1982-96 for the respective fracture type and gender, and applied to the projected population. The annual number of hip fractures increased by 39% in men and 25% in women during the study period. Amongst men, the age-adjusted incidence of cervical fractures increased from 188 to 220/100,000 and of trochanteric fractures from 138 to 170/100,000. In women the incidence of cervical fractures decreased from 462/100,000 to 418/100,000 and of trochanteric fractures from 407/100,000 to 361/100,000. Cervical/trochanteric fracture incidence rate ratio leveled off, and also the female/male fracture rate ratio declined. A prognosis assuming that the incidence development will continue as during 1982-96, and a population in agreement with the forecast, predicts that the total age- and sex-adjusted number of hip fractures will decrease by 11% up to year 2010 compared with 1996. In women and men, however, a decrease of 19% and an increase of 7% respectively were projected. If the age- and sex-specific incidence remains at the same level as at the end of the study period, no significant change in the total numbers will occur. A trend-break was thus found in hip fracture incidence for women but not for men. Whether this is due to therapeutic and/or preventive measures in women is unknown. According to the most probable scenario a substantial increase in male trochanteric fractures (36%) is expected up to 2010, while all other hip fractures in both genders will decrease by 4-32% resulting in a total reduction of 11%.

Age Distribution↗
PubMed2002

Human single masseter muscle fibers contain unique combinations of myosin and myosin binding protein C isoforms.

Striated craniofacial and limb muscles differ in their embryological origin, regulatory program during myogenesis, and innervation. In an attempt to explore the effects of these differences on the striated muscle phenotype in humans, the expression of myosin and myosin-associated thick filament proteins were studied at the single fiber level both in the human jaw-closing masseter muscle and in two limb muscles (biceps brachii and quadriceps femoris muscles). In the masseter, unique combinations of myosin heavy chain (MyHC) and myosin binding protein C (MyBP-C) isoforms were observed at the single fiber level. Compared to the limb muscles, the MyHC isoform expression was more complex in the masseter while the opposite was observed for MyBP-C. In limb muscles, a coordinated expression of three MyHC and three MyBP-C isoforms were observed, i.e., single fibers contained one or two MyHC isoforms, and up to three MyBP-C isoforms. Also, the relative content of the different MyBP-C isoforms correlated with the MyHC isoform expression. In the masseter, on the other hand, up to five different MyHC isoforms could be observed in the same fiber, but only one MyBP-C isoform was identified irrespective MyHC isoform expression. This MyBP-C isoform had a migration rate similar to the slow MyBP-C isoform in limb muscle fibers. In conclusion, a unique myofibrillar protein isoform expression was observed in the human masseter muscle fibers, suggesting significant differences in structural and functional properties between muscle fibers from human masseter and limb muscles.

Adolescent↗
PubMed2002

The inflammatory marker serum eosinophil cationic protein (ECP) compared with PEF as a tool to decide inhaled corticosteroid dose in asthmatic patients.

The objective of this study was to compare the inflammatory marker eosinophil cationic protein (ECP) with peak expiratory flow (PEF) in determining the therapeutic needs of inhaled corticosteroids in asthma patients assessed as asthma symptoms. A randomized, single-blind study over 6 months was performed at six specialist centres in Europe. In total, 164 adult patients with moderate to severe symptomatic asthma and regular use of inhaled corticosteroids were included. After a run-in period of 2 weeks patients were randomly allocated to the ECP or the PEF monitoring group. The dose of inhaled cort costeroids was adjusted every fourth week based on the current serum ECP value or pre-bronchodilator morning PEF values as surrogate markers of therapeutic needs. At the end of the study there were no statistically significant differences in the mean daily symptom score or the percentage of symptom-free days between the two groups. The mean daily dose of inhaled corticosteroids was similar in the two groups at the start of the study but the algorithms used to adjust the dose of inhaled corticosteroids resulted in an increased use of inhaled corticosteroids in both groups. The mean daily dose of inhaled corticosteroids over the whole study period was significantly lower in the ECP group compared withthe PEF group (1246 vs. 1667 microg, P = 0.026). In the ECP group, forced expiratory volume in I sec (FEV)% predicted was lower at the end ofthe study compared with the begining (92% vs. 87%, P = 0 .0009), although there was no significant difference between the two groups. None of the used algorithms for ECP and PEF led to improvement in symptom scores, in spite of increased doses of inhaled corticosteroids. In this respect, both methods were equivalent and insufficient. Recommendations suggesting lung function tests in current guidelines may be difficult to translate into clinical practice, however, a combination of inflammatory markers, lung function and symptoms may still improve asthma control.

Administration, Inhalation↗
PubMed2002

Bone-resorptive effects of endotoxin-contaminated high-density polyethylene particles spontaneously eliminated in vivo.

Wear particles commonly used for experiments may carry adherent endotoxin on their surfaces, which may be responsible for the observed effects. In this study, we attached titanium plates to the tibiae of 20 rats. After osseointegration, endotoxin-contaminated or uncontaminated high-density-polyethylene (HDPE) particles were applied. Contaminated specimens showed a dramatic resorption of bone after seven days but new bone filled the site again at 21 days. Uncontaminated specimens showed no resorption. In 18 rats we implanted intramuscularly discs of ultra-high-molecular-weight polyethylene (UHMWPE) with baseline or excess contamination of endotoxin. Excess endotoxin disappeared within 24 hours and the amount of endotoxin remained at baseline level (contamination from production). Uncontaminated titanium discs did not adsorb endotoxin in vivo. The endotoxin was measured by analytical chemistry. Locally-applied endotoxin stimulated bone resorption similarly to that in experiments with wear particles. Endotoxin on the surface of implants and particles appeared to be inactivated in situ. A clean implant surface did not adsorb endotoxin. Our results suggest that endotoxin adhering to orthopaedic implants is not a major cause for concern.

Animals↗
PubMed2001

IFCC recommendation on reporting results for blood glucose.

In human beings, glucose is distributed like water between erythrocytes and plasma. The molality of glucose (amount of glucose per unit water mass) is the same throughout the sample. Different water concentrations in calibrator, plasma, and erythrocyte fluid can explain some differences that are dependent on sample type, methods requiring sample dilution, and direct reading biosensors detecting molality. Different devices for the measurement of glucose detect and report fundamentally different analytical quantities. The differences exceed the maximum allowable error of glucose determinations for diagnosing and monitoring diabetes mellitus, and they complicate the treatment. The goal of the International Federation of Clinical Chemistry, Scientific Division, Working Group on Selective Electrodes (IFCC-SD WGSE) is to reach a global consensus on reporting results. The document recommends harmonizing to the concentration of glucose in plasma (with the unit mmol/l), irrespective of sample type or technology. A constant factor of 1.11 will convert measured concentration in whole blood to the equivalent concentration in plasma.

Biosensing Techniques↗
PubMed2001

Blood gases and oximetry: calibration-free new dry-chemistry and optical technology for near-patient testing.

The first calibration-free Near-Patient-Testing instrument (NPT7) for blood gases, pH and oximetry has been developed. With cartridges of 30 single-use cuvettes, the NPT7 needs no preparation prior to sample aspiration, no manual calibration, and no maintenance apart from paper and cartridge changes and regulatory quality control. Each cuvette measures pCO2, pO2, pH, total hemoglobin (ctHb), oxygen saturation (sO2), fractions of carboxyhemoglobin (FCOHb) and methemoglobin (FMetHb) on 95 microl whole blood with a 110-s measuring cycle. The measurement principles are as follows: pCO2-three-wavelength infrared spectroscopy of dissolved CO2; pO2-measurement of O2-induced changes in the decay time of phosphorescence; pH-the absorbance spectra change of an azo-dye color indicator; and oximetry is performed with a 128-wavelength spectrophotometer. We determined the within and between instrument variations with tonometered whole blood on seven prototype instruments, using between one and five control levels per analyte. The 95% analytical performance limits: +/-(/Bias/ +2 xS(T)) in the NPT7 instrument matched the analytical performance criteria for the measured quantities as defined by AACC guidelines. The application of these optical measuring methods for blood gases, pH and oximetry in single-use devices introduces a new concept into point-of-care testing (POCT), where preanalytical activities otherwise associated with instrument preparation are eliminated.

Blood Gas Analysis↗
PubMed2001

The prevalence of depression in relation to cerebral atrophy and cognitive performance in 70- and 74-year-old women in Gothenburg. The Women's Health Study.

BACKGROUND: Hospital-based studies report that depression in the elderly is associated with brain atrophy. This notion could not be confirmed in a population study on 85-year-olds. We aimed to assess depression in relation to brain atrophy and cognition in 70- and 74-year-old women. METHODS; A representative sample of 70- and 74-year-old women (N = 501) was examined with a psychiatric examination including the Mini-Mental State Examination (MMSE), measuring global cognitive function, and computerized tomography (CT) of the brain (N = 268). Depression was diagnosed according to DSM-III-R. Previous depression was diagnosed by history and by information from previous examinations in this 24-year longitudinal study. RESULTS: The prevalence of depression was 11.6%, including 8.4% with major depression (MDD). Among those who were currently mentally healthy, 43.0% had a history of previous depression. Women with current MDD had lower scores on the MMSE than the mentally healthy women. This association was only found in women with a lower level of education. Current depressives, previous depressives and mentally healthy women without a history of depression did not differ on CT with regard to brain atrophy or white matter lesions. The association between MDD and lower cognitive performance was independent of the association of cognitive performance with structural brain changes on CT. CONCLUSIONS: Brain atrophy on CT is not associated with depression in the general population, despite the fact that individuals with depression have a worse cognitive performance. The finding that cognitive performance was not decreased in individuals with previous depression suggests that cognitive dysfunction is a state phenomenon in depression.

Aged↗
PubMed2001

Symptom control may improve food intake, body composition, and aspects of quality of life after gastrectomy in cancer patients.

That severe malnutrition affects body function and psychological well-being is well documented. We addressed the question of whether quality of life relates to changes in variables such as food intake, body composition, and gastrointestinal symptomatology after gastrectomy for gastric cancer. Thirty-two patients undergoing gastric resection had their dietary intake, body composition, and specific and general aspects of quality of life determined preoperatively, at 12 months and, in the 15 surviving patients, several years after the operation. The patients lost 10% of their preoperative weight (mainly body fat) during the first year. Food intake did not correlate to changes in body composition or quality of life. Gastrointestinal symptoms adversely related to changes in lean body mass, meal size, and general aspects of quality of life for a long time after the operation. Gastrointestinal symptom control seems important to minimize impairment in quality of life, body composition, and eating after gastrectomy.

Adult↗
PubMed2001

Dental anxiety in relation to mental health and personality factors. A longitudinal study of middle-aged and elderly women.

Little is known about the longitudinal course of dental anxiety in relation to age, mental health and personality factors. In 1968 69 a representative sample of 778 women aged 38 to 54 yr took part in a psychiatric examination. Three hundred and ten were followed up in 1992-93. A phobia questionnaire, including assessment of dental fear, and the Eysenck Personality Inventory were distributed to the participants at both occasions. High dental fear was reported by 16.8% of the women at baseline and was associated with a higher number of other phobias, a higher level of neuroticism, more psychiatric impairment, more social disability due to phobic disorder, and a higher anxiety level. Among women who reported high dental fear in 1968 69 (n=36), 64% remitted and 36% remained fearful. Among women with low dental fear in 1968 69 (n = 274), 5% reported high dental fear in 1992-93. Chronicity was associated with higher neuroticism, lower extraversion, and more psychiatric impairment at base-line. Remission was associated with higher extraversion at baseline. Dental anxiety increased or decreased over time in concert with the number of other fears.

Adult↗
PubMed2001

Effect of chronic renal failure on bone turnover and bone alkaline phosphatase isoforms.

BACKGROUND: Biochemical markers of bone turnover are used to monitor metabolic bone disease associated with renal failure. We have applied a comprehensive panel of markers to patients with chronic renal failure (CRF), with particular focus on the isoforms of bone alkaline phosphatase (BALP). METHODS: Twenty CRF patients undergoing hemodialysis (N = 9) and peritoneal dialysis (N = 11) were measured for serum parathyroid hormone (PTH), osteocalcin, total ALP, and four BALP isoforms (B/I, B1x, B1, and B2) by high-performance liquid chromatography. These BALP isoforms were also compared with BALP measured by three commercial immunoassays (Alkphase-B, Tandem-R Ostase, and Tandem-MP Ostase). Type I collagen turnover was assessed by serum samples using the type I procollagen intact amino- and carboxy-terminal propeptides (PINP and PICP) and two fragments (ICTP and CrossLaps) derived from the carboxy-terminal telopeptide of mature matrix collagen by different degradative pathways. RESULTS: Mean levels of bone turnover markers were elevated in CRF, with marked increases in those markers, osteocalcin, ICTP, and CrossLaps, cleared by the kidney. Total ALP activities were increased corresponding to elevated B/I and B2 isoform levels. The B1 isoform level was not significantly different from healthy controls. B1x was detected in 60% of the patients but was not resolved in healthy individuals. Kendall's tau rank correlation showed that B1x correlated significantly (P < 0.05) with B1 (0.53) and PINP (0.55), and was the only marker to correlate with PTH (0.49). B1x was not significantly correlated with any of the commercial BALP immunoassays. Interestingly, the immunoassay calibrators contained high activities of the B/I peak (39 to 80%) compared with human serum (4%). CONCLUSION: There are selective differences between the BALP isoforms in CRF compared with healthy adults. The commercial BALP immunoassays are comparable with each other but are unable to distinguish the BALP isoform-specific differences in CRF patients.

Adult↗
PubMed2001

A population-based study on brain atrophy and motor performance in elderly women.

BACKGROUND: Brain atrophy is a common neuroimaging finding in healthy elderly individuals as well as in patients with movement-related disorders. The relationship between brain atrophy and motor changes has not been frequently reported. This study investigates this relationship. METHODS: A population-based sample of women (N = 238), aged 70, 74, and 78 years, living in Göteborg, Sweden, participated in this study. Motor performance was measured by a laboratory test, the Postural-Locomotion-Manual test, which precisely measures the subject's mobility of lower and upper extremities using an optoelectronic technique. Cortical and central atrophy were rated on computerized tomographic (CT) scans of the brain. RESULTS: In bivariate analysis, temporal lobe atrophy, high sylvian fissure ratio, and high bicaudate ratio were correlated with impaired mobility. The association between temporal lobe atrophy and high sylvian fissure ratio and poor mobility remained after controlling for age, smoking, coronary heart disease, diabetes mellitus, hypertension, and white matter lesions on CT scans. CONCLUSIONS: Our results suggest that temporal lobe atrophy, which is often seen on brain imaging in elderly persons, might be an important brain abnormality related to motor impairments in elderly women. Further studies to investigate this relationship and its underlying mechanisms are needed.

Age Distribution↗
PubMed2001

Changes in myosin structure and function in response to glycation.

Nonenzymatic glycosylation (glycation) is recognized as an important post-translational modification underlying alterations of structure and function of extracellular proteins. The effect of glycation on intracellular proteins is, on the other hand, less well known despite the vital importance of intracellular proteins for cell, tissue, and organ function. The aim of this study was to explore the effects of glycation on the structure and function of skeletal muscle myosin. Myosin was incubated for up to 30 min with glucose and subsequently tested for structural and functional modifications by matrix-assisted laser desorption/ionization (MALDI) mass spectrometry and a single-fiber in vitro motility assay, respectively. MALDI spectra revealed glycation-related structural alterations as evidenced by the disappearance of specific Lys-C proteolysis products and the appearance of higher mass peaks that are attributed to cross-linking by glucose. This change was paralleled by a significant reduction in the in vitro motility speed, suggesting a structure-related decline in myosin mechanics in response to glucose exposure. Further evidence that early glycation products form in the regulatory regions of the myosin molecule is derived from the fact that there is complete reversal of motility speed after reaction with the Schiff base-cleaving agent hydroxylamine hydrochloride. Thus, glycation of skeletal muscle myosin has a significant effect on both the structural and functional properties of the protein, a finding that is important in understanding the mechanisms underlying the impairment in muscle function associated with aging and diabetes.

Actins↗
PubMed2001

Regional cerebral blood flow in normal individuals aged 40, 75 and 88 years studied by 99Tc(m)-d,l-HMPAO SPET.

Age-related changes in cerebral blood flow (CBF) were examined with [99Tc(m)]-d,l-hexamethylpropylene amine oxime (HMPAO), using a single photon emission tomography (SPET) gamma camera system equipped with a high resolution collimator, in 33 normal individuals in three age groups: 40 years old (n = 11), 75 years old (n = 9) and 88 years old (n = 13). A standard activity of 1000 MBq [99Tc(m)]-d,l-HMPAO was administered. Regional CBF (rCBF) (relative to cerebellar counts) was quantified in 28 grey and white matter regions. The mean rCBF of all the regions was 0.80 (95% confidence interval [CI] 0.77-0.83) in 40 year olds, 0.77 (0.74-0.80) in 75 year olds and 0.76 (0.73-0.78) in 88 year olds. rCBF in the hippocampus, angular and cingular gyri, and frontal association and motor cortices was 5-10% lower in the 75 and 88 year olds than in the middle-aged subjects (P < 0.05). The annual reduction in rCBF was 0.10% between the ages of 40 and 75 years and 0.13% between the ages of 75 and 88 years. The reduction in rCBF in the hippocampus rose from 0.14% between the ages of 40 and 75 years to 0.33% between the ages of 75 and 88 years. The mean rCBF in all 33 individuals showed no sex-related differences.

Adult↗
PubMed2001

Effects of aging on regulation of muscle contraction at the motor unit, muscle cell, and molecular levels.

Rodent motor units, muscle fibers, and motor proteins undergo significant aging-related changes. Such changes include spatial organization and physiological properties of fast- and slow-twitch single motor units, regulation of contractile speed and force generation capacity at the muscle fiber level, and altered functional properties of the motor protein myosin. In addition to specific changes, there also appears to be a "disorganization" of the coordinated expression of contractile, sarcoplasmic reticular, and mitochondrial protein isoforms in aging skeletal muscle. This is suggested to have a strong impact on aging-related impairments in muscle function in addition to the changes in specific muscle proteins.

Adaptation, Physiological↗