Biomedical subjects

J Karlsson

Publications and source records attributed to J Karlsson.

At least 163 records · Page 9Linked to original sources

PubMed1995

Swedish Obese Subjects (SOS)--an intervention study of obesity. Measuring psychosocial factors and health by means of short-form questionnaires. Results from a method study.

Lengthy questionnaires should be shortened to enable better compliance in large-scale trials also ensuring adequate measurement precision. As the number of questions sufficient to create reliable scales may vary considerably depending on the complexity of concepts and purposes, consecutive participants of a large study, the Swedish Obese Subjects (SOS), received a second mailing of original long-form questionnaires after 1 week to be compared with the SOS short-form measures. Internal consistency, unidimensionality, robustness and reproducibility were tested for scales reflecting social support and life events, personality traits, health perception and psychosocial functioning. Very brief generic scales could perform satisfactorily for study-specific purposes in diseased populations. The short-form social support scales yielded satisfactory psychometric properties and the short life events module was best divided into two multi-item variables. High and consistent metric values were found for the personality, general health and psychosocial functioning scales. Our method study thus guided in striking a balance between scaling properties/reliability levels and length of questionnaires/subject burden. We recommend a method study like ours in every instance where patient-based data recordings are among the primary measures of outcome.

Attitude to Health↗

PubMed1995

Intracellular carbonic anhydrase of Chlamydomonas reinhardtii.

An intracellular carbonic anhydrase (CA; EC 4.2.1.1) was purified to homogeneity from a mutant strain of Chlamydomonas reinhardtii (CW 92) lacking a cell wall. Intact cells were washed to remove periplasmic CA and were lysed and fractionated into soluble and membrane fractions by sedimentation. All of the CA activity sedimented with the membrane fraction and was dissociated by treatment with a buffer containing 200 mM KCI. Solubilized proteins were fractionated by ammonium sulfate precipitation, anionic exchange chromatography, and hydrophobic interaction chromatography. The resulting fraction had a specific activity of 1260 Wilbur-Anderson units/mg protein and was inhibited by acetazolamide (50% inhibition concentration, 12 nM). Final purification was accomplished by the specific absorption of the enzyme to a Centricon-10 microconcentrator filter. A single, 29.5-kD polypeptide was eluted from the filter with sodium dodecyl sulfate-polyacrylamide gel electrophoresis sample buffer, and a 1.5 M ammonium sulfate eluate contained CA activity. In comparison with human CA isoenzyme II, the N-terminal and internal amino acid sequences from the 29.5-kD polypeptide were 40% identical with the N-terminal region and 67% identical with an internal conserved region. Based on this evidence, we postulate that the 29.5-kD polypeptide is an internal CA in C. reinhardtii and that the enzyme is closely related to the alpha-type CAs observed in animal species.

Acetazolamide↗

PubMed1995

Methylmethacrylate monomer produces direct relaxation of vascular smooth muscle in vitro.

Methylmethacrylate bone cement is associated with severe hypotensive reactions during surgery and anesthesia. The purpose of this in vitro study was to determine if methylmethacrylate monomer could produce hypotension by acting directly on vascular smooth muscle. Segments of human saphenous vein or rabbit thoracic aorta were cut into rings. The rings were mounted in isolated tissue chambers in order to measure isometric tension development. Methylmethacrylate monomer (methylmethacrylic acid ester) produced direct relaxation of venous or aortic rings preconstricted with either potassium ion or noradrenaline. The relaxation was concentration-dependent, occurring at concentrations from 10(-3) to 10(-1) M. The relaxation of rabbit aortic rings (preconstricted with noradrenaline) was unaffected by pre-treatment with atropine, propranolol, cimetidine, indomethacin, or methylene blue. Endothelial stripping with Triton X-100, sufficient to completely abolish acetylcholine-induced relaxation, also had little effect on methylmethacrylate-induced relaxation. Methylmethacrylate produced direct relaxation of rabbit aortic rings constricted with either potassium or noradrenaline in calcium-deficient media, and inhibited subsequent calcium-induced constriction. These results suggest that methylmethacrylate monomer may interfere with intracellular and extracellular calcium mobilization and excitation/contraction coupling in vascular smooth muscle. The direct relaxation of venous and arterial smooth muscle produced by methylmethacrylate monomer may contribute in part to the hypotension that can occur when acrylic bone cement is employed during orthopedic procedures.

Animals↗

PubMed1995

Repair of Bankart lesions with a suture anchor in recurrent dislocation of the shoulder.

This study describes the 3-year results of Bankart reconstruction in 50 consecutive patients with posttraumatic, recurrent, anterior instability of the shoulder. A modified procedure, using suture anchors was used in all patients, to simplify the soft-tissue attachment to the glenoid rim. Forty-seven of 50 (94%) patients regained normal stability. Two recurrent dislocations and one subluxation occurred. The functional results according to the Rowe scoring system were satisfactory in 43 of 50 (86%) of the patients, and unsatisfactory in 7 of 50 (14%). Of the patients with unsatisfactory results, 3 had recurrent instability and 4 had not regained normal range of shoulder motion. The suture anchors were found to simplify the procedure, and no specific complications as a result of the modified technique were seen.

Adolescent↗

PubMed1995

Patellofemoral pain syndrome in young women. I. A clinical analysis of alignment, pain parameters, common symptoms and functional activity level.

Clinical alignment, pain variables, common symptoms and functional activity level associated with patellofemoral pain syndrome (PFPS) were evaluated in 40 women with PFPS and 20 healthy controls. No significant difference could be found neither between the patients' most symptomatic knee and least symptomatic knee, nor between the patients and controls regarding clinical lower extremity alignment, such as Q-angle and leg-heel alignment measurements. There were no radiographic signs of malalignment. The patients were significantly more involved competitively in sports but had a significantly lower pain free activity level than the controls. Pain was associated with increased activity. It is suggested that chronic overloading and temporary overuse of the patellofemoral joint, rather than malalignment, contribute to patellofemoral pain.

Activities of Daily Living↗

PubMed1995

Patellofemoral pain syndrome in young women. II. Muscle function in patients and healthy controls.

Muscle function was evaluated in 40 patients with patellofemoral pain syndrome (PFPS) and 20 healthy controls. Patients with PFPS had a significantly lower knee extensor strength in the most symptomatic knee compared to the least symptomatic knee. Further, the patients had less vertical jumping ability and were weaker in the most symptomatic knee compared to the controls, with the largest differences in eccentric knee extension. There were lower strength and EMG activity, in the patients compared to the controls, in the range closer to full extension and significant differences in muscle activity between the vastus medialis and the rectus femoris muscle. The results can be explained by inhibition selective to knee angles and to the vastus medialis muscle.

Adolescent↗

PubMed1994

Predictors and effects of long-term dieting on mental well-being and weight loss in obese women.

Sixty moderately obese women (mean BMI = 33, mean age = 43), randomized to a lactovegetarian or regular 1300-kcal weight-reducing diet were followed at 3, 8 and 24 months. Weight follow-up was 92%, while 47% complied with the program throughout with no differences between the two diets with respect to compliance rate, weight loss or behavioral test results. Over 24 months compliers lost a mean 3.9 kg compared to a gain of 1.8 kg in the non-compliers. Short-term improvements in mental well-being measured by the Mood Adjective Check List deteriorated after 2 years to lower levels than at entry. Self-assessed motivation to diet was inversely related to mental well-being at two years. Positive long-term changes of functional status (Sickness Impact Profile) were found. Though subjective prediction of success measured after 3 weeks on diet predicted short-term and maximum weight loss, it did not predict ultimate outcome. More difficulties in resisting emotional and social eating cues (high disinhibition score on the Three-Factor Eating Questionnaire) before and during the diet predicted weight gain. The more initial health-related dysfunction (SIP) the greater the weight regain. Psychological characteristics at baseline did not predict compliance or overall weight loss. The magnitude of weight loss after 24 months was related to amount and duration of maximum weight loss.

Adult↗

PubMed1994

Physical fitness and insulin sensitivity in human subjects with a low insulin response to glucose.

1. We have assessed insulin secretion, insulin sensitivity, exercise capacity and muscle fibre composition in healthy men with a low insulin response to glucose (low insulin responders and endurance-trained subjects) and in healthy men with a normally high insulin response. Low insulin responders have been considered as prediabetic subjects. 2. During glucose infusion, low insulin responders and endurance-trained subjects had acute-phase (0-10 min) insulin responses that were 26% (P < 0.001) and 31% (P < 0.001), and C-peptide responses that were 35% (P < 0.001) and 42% (P < 0.01), respectively of the responses in high insulin responders. Also, the late-phase (10-60 min) insulin and C-peptide responses were lower in low insulin responders and endurance-trained subjects. Endurance-trained subjects, compared with high and low insulin responders, had higher insulin sensitivity (blood glucose concentration during a somatostatin-insulin-glucose infusion test 3.6 +/- 0.4 versus 6.3 +/- 0.6 mmol/l in high insulin responders, P < 0.01, and 5.5 +/- 0.4 mmol/l in low insulin responders, P < 0.01), exercise capacity (4.2 +/- 0.2 versus 3.0 +/- 0.2 W/kg body weight, P < 0.001, and 2.8 +/- 0.1 W/kg body weight, P < 0.001) and a higher percentage of slow-twitch fibres (58.2 +/- 5.2 versus 38.5 +/- 3.5%, P < 0.01 and 40.9 +/- 3.0%, P < 0.001). 3. In conclusion, we demonstrate that low insulin responders exhibited decreased insulin and C-peptide responses to glucose, despite normal insulin sensitivity and exercise capacity.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1994

Chronic groin injuries in athletes. Recommendations for treatment and rehabilitation.

Chronic muscle and tendon injuries to the groin are common sports injuries. The symptoms of groin injuries are often uncharacteristic which can result in a delay in the correct and specific diagnosis being reached. The most common injury is the overuse strain resulting in chronic tendinitis of the adductor muscle/tendon units, especially the adductor longus. The rectus femoris and rectus abdominous muscles and tendons are also commonly affected. Computed tomography, magnetic resonance imaging and ultrasonography have been widely adopted to diagnose muscle/tendon injuries to the groin. Ultrasonography has been shown to be accurate and sensitive in diagnosing tendon injuries in the groin region, especially small partial ruptures of the muscle/tendon unit. Ultrasonography has the advantage of being fast, inexpensive and widely available. Normal findings are readily distinguished from pathological findings providing valuable pre-operative information, such as location and extent of the injury. The differential diagnoses are many and often difficult to reach. The most commonly overlooked differential diagnoses are chronic prostatitis and hernias. A multidisciplinary approach is valuable in many cases. The recommended treatment is well planned and gradually increased rehabilitation programme during the first stages. Surgery for acute injuries is rarely indicated. Surgery, for example tenotomy of the adductor longus, has given satisfactory results in many athletes when nonsurgical treatment has failed.

Athletic Injuries↗

PubMed1993

Heart muscle ubiquinone and plasma antioxidants following cardiac transplantation.

Nine patients who underwent heart transplantation (one female; average age 48 +/- 11, range 19-58 years) were followed in respect to contents of right-sided heart septum, blood and plasma ubiquinone (UQ), plasma alpha-tocopherol (alpha T), and plasma free cholesterol (FC). In contrast to healthy persons, substantial inter- and intraindividual variations were observed; individually low values were seen with rejection. Heart muscle UQ in well-treated patients averaged 0.33 +/- 0.08, range 0.06-0.58 micrograms mg-1 (0.38 +/- 0.09 mumol g-1 dry weight) and was not different from healthy individuals. Plasma UQ, alpha T; and FC averaged 0.63 +/- 0.33 micrograms ml-1 (P < 0.05 versus sedentary controls), 8.1 +/- 4.0 micrograms ml-1 (P < 0.01), and 0.52 +/- 0.23 mg ml-1 (P < 0.05). Corresponding molar values were 0.73 +/- 0.37 (UQ), 2.0 +/- 1.1 mumol l-1 (alpha T), and 1.42 +/- 0.54 mmol l-1 (FC). Blood and plasma UQ values were identical. A saturation like relationship was found between heart and blood UQ:blood contents below 0.7 micrograms ml-1 (0.8 mumol l-1) corresponded to markedly lowered heart contents. In four patients in whom blood samples were taken close to a fatal complication it averaged 0.42 micrograms ml-1 (0.49 mumol l-1, P < 0.01). When low heart muscle and blood ubiquinone were present, other variables such as left ventricle cardiac output or cycle ergometer performance was markedly impaired. Plasma UQ and alpha T covaried with a marker of the lipoidal deposit volume, plasma FC.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1993

Ubiquinone and alpha-tocopherol in plasma; means of translocation or depot.

Ubiquinone (UQ) and alpha-tocopherol (AT) are two highly lipophilic antioxidants which can be dissolved only in lipid layers or attached to protein structures. Analyses of both UQ and AT in whole blood and plasma demonstrate identical values, which excludes any significant allocation to blood cells. The lipoidic plasma structures constitute the plasma lipoprotein fractions of high (HDL), low (LDL), and very low (VLDL) density in addition to chylomicrons. This means by definition that blood and plasma UQ and AT values are limited if not related to the lipoidic deposit volume. UQ and AT increase linearly with free cholesterol (FC). FC has therefore been suggested to be a good marker for the deposit volume. The ratios UQ and AT over FC--normalized UQ (N-UQ) and normalized AT (N-AT)--have been computed for inter- and intraindividual comparisons. With a plasma UQ content of 1 microgram/ml (approximately 1 mumol/l) and a plasma volume of 41, UQ makes up about 15% of the total heart content or under 1% of UQ in skeletal muscle. The corresponding value for the total extracellular UQ content is less than 2%. This means that extracellular UQ has no or a very minor role as a UQ depot. The same is true for AT. However, for transportation and allocation determinations of N-UQ and N-AT are relevant. Assuming only a lipoprotein-related transportation, healthy persons have saturated plasma UQ and AT values in only 25% and 10% of the population, respectively. All patient categories studied have been found nonsaturated. VLDL plus LDL constitute some 90% of the UQ deposit volume.(ABSTRACT TRUNCATED AT 250 WORDS)

Humans↗

PubMed1993

A drug absorption model based on the mucus layer producing human intestinal goblet cell line HT29-H.

A new drug absorption model based on monolayers of the human intestinal goblet cell line HT29-H grown on permeable filters has been characterized. HT29-H cells have been shown (a) to form monolayers of mature goblet cells under standard cell culture conditions, (b) to secrete mucin molecules, (c) to produce a mucus layer that covers the apical cell surface, and (d) that this mucus layer is a significant barrier to the absorption of the lipophilic drug testosterone. This is the first demonstration of an intact human mucus layer with functional barrier properties produced in cell culture. The results indicate that monolayers of HT29-H cells provide a valuable complement to mucus-free drug absorption models based on absorptive cell lines such as Caco-2 cells.

Adenocarcinoma↗

PubMed1993

The impact of intermittent claudication on quality of life evaluated by the Sickness Impact Profile technique.

Unselected patients suffering from intermittent claudication (n = 148) were invited to take part in a prospective study. Physical examination and several circulatory investigations were performed including a treadmill walking test, bicycle ergometry and a quality of life examination (Sickness Impact Profile, SIP, technique). The SIP has been reported to be sensitive enough to identify specific dysfunction profiles in several clinical conditions, but it has not been used on patients with intermittent claudication. The aim of this study was to determine to what extent quality of life was influenced by reduced walking ability in patients with intermittent claudication. If so, the SIP technique should then be a useful tool for determination of the degree of reduced exercise capacity in patients who may benefit from surgery instead of conservative treatment. A majority of the SIP categories, Sleep and rest, Emotional behaviour, Body care and movement, Home management, Mobility, Social interaction, Ambulation and Overall SIP were shown to be useful in confirming objective dysfunctions in our patients. The correlation between maximum walking ability and SIP scores indicated an approximate cut-off limit at 70 W walking capacity. Thus, significant reductions in everyday life function were demonstrated in patients with maximum walking ability below 70 W. Patients with intermittent claudication also suffered from several other dysfunctions in addition to walking disability. These factors may, as well, impact on quality of life without walking disability. Our results demonstrated that quality of life assessment by the SIP technique was a sensitive method for evaluation of overall dysfunction in patients with intermittent claudication.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

PubMed1993

Transport of celiprolol across human intestinal epithelial (Caco-2) cells: mediation of secretion by multiple transporters including P-glycoprotein.

1. The transepithelial transport of the beta-adrenoceptor blocking drug, celiprolol, was investigated in monolayers of the well differentiated human intestinal epithelial cell line, Caco-2. 2. The basal-to-apical transport (secretion) of [14C]-celiprolol (50 microM) was 5 times higher than apical-to-basal transport (absorption). In the presence of an excess (5 mM) of unlabelled celiprolol the basal-to-apical transport was reduced by more than 80%, whereas the apical-to-basal transport remained unchanged. 3. Net celiprolol secretion obtained in the concentration range 0.01 to 5 mM displayed saturable kinetics with an apparent Km of 1.00 +/- 0.23 mM and Vmax of 113 +/- 11 pmol/10(6) cells min-1. These results are consistent with saturable active secretion and provide an explanation for the dose-dependent bioavailability of celiprolol. 4. The secretion of celiprolol was sensitive to pH, and decreased in the absence of sodium and in the presence of ouabain, suggesting that transport was coupled to proton and sodium gradients. 5. The secretion of celiprolol was inhibited by substrates for P-glycoprotein (vinblastine, verapamil and nifedipine) and either inhibited or stimulated by typical substrates for the renal organic cation-H+ exchanger (cimetidine, N1-methylnicotinamide, tetraethylammonium and choline), suggesting that there are at least two distinct transport systems. 6. The secretion of celiprolol was also inhibited by other beta-adrenoceptor blocking drugs (acebutolol, atenolol, metoprolol, pafenolol and propranolol) and by the diuretics, acetazolamide, chlorthalidone and hydrochlorothiazide, suggesting that the clinically observed effect of chlorthalidone on the bioavailability of celiprolol occurs at the level of the intestinal epithelium.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

PubMed1993

The effect of taping on ankle stability. Practical implications.

Ankle ligamentous injuries are very common in sports. One of the most popular methods of supporting the weakened ankle is external support with ankle tape. The tape can be used to prevent ankle injuries, to stabilise the injured ankle to prevent further injury, and as a stabiliser during the rehabilitation phase. Of the various taping methods, basket weaves (combined with stirrup and a heel-lock) are the most effective for increasing the mechanical stability of the ankle, especially in the frontal plane (talar tilt). A combination of increased mechanical stability, decreased range of ankle motion and an improvement in the proprioceptive function of the ankle ligaments are factors associated with effectiveness of ankle taping. The major drawbacks of ankle taping are the high costs and decreased support after exercise.

Ankle Injuries↗

PubMed1993

Chronic lateral instability of the ankle in athletes.

Acute lateral ligament injuries of the ankle are best treated nonsurgically, with peroneal strengthening and neuromuscular training. At least 80 to 90% of patients will regain satisfactory ankle stability after functional treatment. Chronic ankle instability occurs in approximately 10 to 20% of patients after acute ligament injuries, irrespective of primary treatment. Surgical reconstruction may be necessary, especially in athletes with high demands on ankle joint stability. Numerous different surgical procedures have been described many with some kind of a tenodesis. The classic tenodeses, Evans, Watson-Jones and Chrisman-Snook, have all been used with good short term results. Anatomical ligament reconstruction using the remnants of the ruptured and elongated ligaments, with shortening, reinsertion and duplication, have been shown to be simple, effective and free from complications. As the results of anatomical reconstruction are satisfactory both in the short and the long term, this reconstruction is recommended for correction of lateral ankle instability.

Ankle Injuries↗

PubMed1993

"The Göteborg Quality of Life Instrument"--a psychometric evaluation of assessments of symptoms and well-being among women in a general population.

OBJECTIVE: To examine with psychometric analysis techniques the potential for constructing valid composite variables of "The Göteborg Quality of Life Instruments". DESIGN: Prospective population study of women in 1974-75 and in 1980-81. SETTING: City of Göteborg, Sweden. PARTICIPANTS: Representative samples of the general population of women in five age strata between 44 and 66 years of age in 1974-75, followed 1980-81 including new cohorts of women aged 26 and 38. 1302 women were examined in 1974-75 and 1408 in 1980-81. MAIN OUTCOME MEASURE: "The Göteborg Quality of Life instrument", constructed in the early 1970s to measure symptoms and well-being in a population study of men. RESULTS: Four multi-item scales were identified with satisfactory reliability and validity, i.e., they met defined criteria of multi-item scales and benefit from higher reliability than single questions. The psychological symptom scale comprised all ten questions intended to reflect depression and tension, while the physical symptom scale included all six pain questions, the general symptoms dizziness, breathlessness, and nausea, and general fatigue that belonged to both symptom scales. The social well-being scale comprises all well-being questions believed to reflect the broad concept of life satisfaction. The physical-mental wellbeing scale reflected satisfaction with both general and mental health. Several symptom and well-being questions were clearly outside the main clusters and should be treated as single items. CONCLUSIONS: Use of a few, distinct scales instead of a number of single questions should increase statistical power because the number of comparisons is greatly reduced and problems of chance findings are thus minimized.

Adult↗

PubMed1993

Health status assessment in rheumatoid arthritis. II. Evaluation of a modified Shorter Sickness Impact Profile.

OBJECTIVE: To develop a shortened form of the Sickness Impact Profile (SIP) for routine practice. METHODS: We used data from a study of health status in 99 women with rheumatoid arthritis (RA). A stepwise analysis model used physical discomfort (global rating), self-assessed pain (Body Symptom Scale), mental well-being (Mood Adjective Check List) and joint function (Keitel Index) to define important aspects of health. RESULTS: Short forms of the SIP for discrimination (53 items), evaluation (25 items) and prediction (28 items) compared well in validity to the original 136-item SIP. The discriminative short form showed excellent reliability (internal consistency), matching the level of the generic SIP. The evaluative and predictive short forms had acceptable but lower internal consistency than the original Profile. CONCLUSION: We suggest a 64-item core health status questionnaire (SIP-RA) to be included and further tested in the arsenal of routine measurements in outpatients with RA. The questionnaire should include physical (Body care and movement, Mobility), psychosocial (Emotional behavior, Social interaction, Alertness behavior, Communication) and free-standing (Sleep and rest, Home management, Recreation and past-times, Eating) SIP categories, and it will improve the description of patients with RA.

Adult↗