Biomedical subjects

K Bergström

Publications and source records attributed to K Bergström.

At least 37 records · Page 2Linked to original sources

PubMed2001

Persistence of granulocytic Ehrlichia infection during wintertime in two sheep flocks in Norway.

Granulocytic Ehrlichia infection in sheep is common in Norway in areas with Ixodes ricinus. In this study, 2 sheep flocks that had been grazing on I. ricinus infested pastures the previous season, were blood sampled after being housed indoors for nearly 6 months during wintertime. Thirty animals from each flock were examined for granulocytic Ehrlichia infection in the peripheral blood by blood inoculation studies, stained blood smear evaluation, polymerase chain reaction (PCR) analysis and serology (IFA-antibodies). The animals were sampled twice within a three-week period, the first time before and the second time after lambing. Two sheep in one flock were found Ehrlichia positive by both blood smear evaluation and PCR before lambing, and 3 sheep were found positive after lambing; 2 by blood smear examination and 3 by PCR. In the other flock, no sheep was found infected before lambing, but 2 ewes were found positive after lambing by both blood smear evaluation and PCR. In the first flock, 87% of the animals were found seropositive before lambing, and the mean antibody titre (log10 +/- SD) to E. equi was 2.45 +/- 0.401. In the second flock, 40% were found seropositive before lambing, and the mean antibody titre was 1.93 +/- 0.260. Seroprevalence and mean antibody titre in these 2 flocks were significantly different (p < 0.001). The present study indicates that sheep may be a reservoir host for granulocytic Ehrlichia infection from one grazing season to the next under natural conditions in Norway.

Animals↗

PubMed2001

Persistence of Ehrlichia phagocytophila infection in two age groups of lambs.

Tick-borne fever (TBF) is caused by the rickettsiae Ehrlichia phagocytophila and is a common disease in sheep in tick (Ixodes ricinus) infested areas in Norway. Earlier investigations have shown that some sheep could remain infected for several months after the primary infection. In this study, the persistence of E. phagocytophila after experimental infection was investigated in 2 age groups of lambs. Six lambs (1-2 weeks old) and 14 lambs (6-8 months old) were inoculated intravenously with an ovine strain of E. phagocytophila and thereafter examined clinically (including daily body temperature recording) and by haematological and serological (E. equi antibodies) methods for the next 4 months. At the end of this period, the lambs were examined for a TBF infection by blood smear investigation and blood inoculation studies. The infection was demonstrated in 19 (95%) of the 20 lambs.

Age Factors↗

PubMed2000

Improvement of urge- and mixed-type incontinence after acupuncture treatment among elderly women - a pilot study.

The aim of this study was to investigate if sensory stimulation in the form of manual acupuncture could influence urge- or mixed-type incontinence among elderly women who were not satisfactorily relieved by standard pharmacological and non-pharmacological treatments given at a specialised incontinence unit. The study is an open clinical follow-up study. The study included 15 elderly women who were treated with manual acupuncture 12 times. Both subjective scorings and objective measurements in the form of leakage in grams (48 h Inco-test) were used. Evaluations were performed at discharge and 1 and 3 months thereafter. Almost all outcome measurements were significantly improved even at follow-up 3 months after the last treatment. Global scorings showed that 12 of the 15 women considered themselves improved even at the follow-up 3 month after treatments were completed. The possible mechanisms of action are discussed, as is the way to perform more studies in this field.

Acupuncture Therapy↗

PubMed2000

Pulmonary deposition of lactose carriers used in inhalation powders.

Dry powder dosage forms are generally formulated by mixing the micronized drug particles with the larger carrier particles. Lactose is a commonly used carrier. Carriers enhance the flowability of powder mixtures and therefore enable low dosing of active substances. During inhalation, the drug particles are dispersed from the surface of carrier particles. The aim of this study was to compare how different qualities of 99mTc-labelled lactose carrier systems deposit in the lungs. The sizes of the labelled and unlabelled alpha-lactose monohydrate particles were compared by using a laser diffraction method. Distribution of radiolabel between different particle size fractions was determined using the Andersen cascade impactor. The in vivo depositions of lactose carrier systems were investigated in ten healthy men using the technique of gammascintigraphy. In addition, redispersion of budesonide from the carrier materials was evaluated by using the Andersen cascade impactor. According to the validation data the particle size of the lactose carriers remained unchanged during the labelling process. Low pulmonary deposition varying between 2.5 and 3.3% was detected. Only a small amount of lactose was deposited in the lungs, thus pulmonary deposition is not a limiting factor for lactose selection. According to in vitro redispersion data the fine particle fraction of the delivered dose in the impactor varied between 10.3 and 26.0%. Thus, the redispersion of the budesonide particles can be altered by the properties of the carrier system.

Administration, Inhalation↗

PubMed2000

Cigarette smoking as an aggravating factor in inflammatory tissue-destructive diseases. Increase in tumor necrosis Factor-alpha priming of peripheral neutrophils measured as generation of oxygen radicals.

Stimulated neutrophils from subjects with various inflammatory tissue-destructive conditions, such as periodontal, pulmonary, gastrointestinal, and cardiovascular diseases, generate more oxygen radicals and proteases, implicated in tissue destruction, than neutrophils from healthy persons. Cigarette smoking aggravates these diseases. The aim of our study was to investigate the effect of cigarette smoking on the priming capacity of tumor necrosis factor-alpha, measured as generation of radicals from stimulated neutrophils, in smoking and non-smoking subjects with or without periodontitis. The priming effect was higher in neutrophils from smokers. In the group with periodontitis, smoking caused an even greater increase in the generation of radicals, indicating an additive effect of this local disease. The membrane expression of CD11b, CD15, and CD63 was significantly higher on neutrophils from smokers, indicating upregulated neutrophil functions. This increased priming effect of tumor necrosis factor-alpha in smokers subjects could be of importance in the aggravation of tissue-destructive inflammatory diseases.

Adult↗

PubMed2000

Expression of intracellular elastase activity in peripheral neutrophils from patients with adult periodontitis.

This study aimed to investigate whether circulating neutrophils from patients with periodontitis contain more catalytically active elastase than neutrophils from healthy controls. The amount of IL-1beta in these cells was also analyzed and the correlation with elastase activity was tested. The periodontitis group consisted of 15 subjects with marked periodontal destruction. The healthy control group consisted of 15 subjects with no clinical signs of periodontal destruction. The elastase activity and the IL-1beta content in the cells were measured with flow cytometry using a specific substrate and antibodies, respectively. The plasma concentration of IL-1beta and the total content of antigenic elastase in the crushed cells were measured with an ELISA. The elastase activity per neutrophil was significantly higher in the patients than in the controls, while the total antigenic elastase content did not differ. The % of cells positively stained for IL- 1beta was somewhat higher in the patient group. Significantly higher amounts of IL-1beta per sample, estimated by multiplying the % of stained cell with the amount of staining per cell, were found in the patient group. A significant correlation between IL-Ibeta and elastase activity was noted in the patient group (R=0.6, p=0.001), but not in the control group. In conclusion, peripheral neutrophils from patients with adult periodontitis express more active elastase and total amounts of IL-1. The similar amounts of antigenic elastase suggests that this higher activity is possibly due to some kind of priming/activation already in the circulation.

Case-Control Studies↗

PubMed1999

Long-term study of quality and safety of osseointegration for the retention of auricular prostheses.

The aim of this article is to describe the safety and quality of the osseointegrated implant technique for the retention of craniofacial prostheses, to present a protocol for collection of clinical data, and to discuss the impact of the procedure on the patient quality of life. A protocol was designed and used to study patients who had received auricular prostheses consecutively since 1979 at our department. The patients were asked to answer a questionnaire designed to describe symptoms and problems specific for someone wearing an auricular prosthesis. In total, 99 patients received 107 prosthetic ears (8 patients had bilateral defects) retained on 309 implants (2 to 4 implants/ear). Patients of all ages were represented, and only 9 discontinuities were reported. Most patients (95%) wear their prosthesis every day, in most cases more than 10 hours/day. The follow-up period ranged from 1 to 12 years, giving a total of 2624 postoperative observations of implants, with a 3% incidence of significant skin reaction. We conclude that the surgical technique for auricular prostheses retained on osseointegrated implants is simple and associated with a low rate of peroperative and long-term complications. It offers a high degree of stability and aesthetic satisfaction.

Adolescent↗

PubMed1999

Increased release of elastase from in vitro activated peripheral neutrophils in patients with adult periodontitis.

The main object of this study was to determine if there was a difference between patients with adult periodontitis and healthy controls in the release of elastase. We also wanted to test the release of alpha-1-antitrypsin and lactoferrin from in vitro-activated peripheral neutrophils. A leukocyte-rich preparation from venous blood was made by lysing the red blood cells. The leukocytes were stimulated for 1 h at 37 degrees C with opsonized Staphylococcus aureus and the released elastase was measured with a chromogenic substrate. The release of elastase after stimulation with bacteria was significantly higher in patients than in controls. The amounts of elastase from unstimulated cells, i.e., both released extracellularly and extracted from the pellet, were similar in the 2 groups. However, after stimulation, the amount of elastase in the patient group, but not in the control group, was significantly increased. Similar releases of alpha-1-antitrypsin (AIAT) and lactoferrin were found in both groups of subjects. In conclusion, this study shows that peripheral neutrophils from patients with adult periodontitis release more active elastase after in vitro activation compared to healthy controls. The release of A1AT and lactoferrin showed no differences, indicating that the increased elastase activity was not due to a impaired inhibition by A1AT and that the differences in degranulation were limited to the primary granula.

Adult↗

PubMed1999

Nanobacteria: an infectious cause for kidney stone formation.

BACKGROUND: Nanobacteria are cytotoxic, sterile-filterable, gram-negative, atypical bacteria detected in bovine and human blood. Nanobacteria produce carbonate apatite on their cell walls. Data on Randall's plaques suggest that apatite may initiate kidney stone formation. We assessed nanobacteria in 72 consecutively collected kidney stones from Finnish patients. METHODS: Nanobacteria and kidney stone units were compared using scanning electron microscopy (SEM). Demineralized kidney stones were screened for nanobacteria using a double-staining method and a specific culture method. Isolated nanobacteria were analyzed for mineral formation in vitro with Ca and 85Sr incorporation tests. RESULTS: SEM highlighted the resemblance in size and morphology of nanobacteria and the smallest apatite units in the kidney stones. Nanobacterial antigens could be detected after the demineralization of the stones in 1 N HCl. Nanobacteria were surprisingly resistant to this treatment, and cultures could be established from 93.1% of the stones. Only struvite stones had common bacteria, in addition to the nanobacteria. When the results of all of the assays were combined, 70 of the 72 stones (that is, 97.2%) were nanobacteria positive. Although apatite stones indicated highest nanobacteria antigen signals, the overall nanobacteria positivity did not depend on the stone type. The isolated nanobacteria produced apatite stones in vitro, measured by Ca and 85Sr incorporation. CONCLUSIONS: We propose that kidney stone formation is a nanobacterial disease analogous to Helicobacter pylori infection and peptic ulcer disease. Both diseases are initiated by bacterial infection and subsequently endogenous and dietary factors influence their progression.

Calcium↗

PubMed1999

Actinomyces bowdenii sp. nov., isolated from canine and feline clinical specimens.

Four strains of a previously undescribed Actinomyces-like bacterium were isolated from canine and feline clinical specimens. Phenotypic studies indicated the strains were members of the genus Actinomyces, and most closely resembled Actinomyces viscosus serotype I and Actinomyces slackii. Comparative 16S rRNA gene sequencing studies demonstrated the unknown bacterium constitutes a new subline within a group of Actinomyces species, which includes Actinomyces bovis, the type species of the genus. Based on phylogenetic and phenotypic evidence it is proposed that the unknown bacterium be classified as Actinomyces bowdenii sp. nov. The type strain of Actinomyces bowdenii is CCUG 37421T.

Actinomyces↗

PubMed1999

Periodontitis increases chemiluminescence of the peripheral neutrophils independently of priming by the preparation method.

OBJECTIVE: The aim was to investigate whether increased Fcgamma-receptor (FcgammaR)-induced chemiluminescence (CL) from peripheral neutrophils in periodontitis could be due to increased sensitivity to non-specific priming by the cell preparation. DESIGN: Two methods of preparation were used: (1) cells purified by density centrifugation and lysis of erythrocytes; and (2) cells in a leukocyte suspension obtained by lysis of erythrocytes alone. METHODS: Neutrophils from 17 subjects with periodontitis and pair-matched healthy controls were studied by CL and flow cytometry (CD16, CD15 and CD11b). RESULTS: Higher CL was found in the purified neutrophils, indicating higher non-specific priming by the Percoll density centrifugation. Priming with TNFalpha and lipopolysaccharide abolished this difference. The net effect of specific priming was significantly lower in the purified neutrophils, indicating a depletion of the priming sensitivity by the density centrifugation. Both preparations reduced CD15 in relation to whole blood, while there was no difference between the two methods in any of the membrane markers. Thus, in both preparations, lysis alone changed the membranes to the same extent. Both methods gave nearly the same relative CL increase in the periodontitis patients as in the controls. CONCLUSION: There was no difference between the neutrophils from patients and controls in sensitivity to non-specific priming by the preparation method. The higher FcgammaR-induced CL in patients with periodontitis is not related to such a non-specific priming by density centrifugation.

Adult↗

PubMed1998

Treatment difficulty and treatment outcome in orthodontic care.

The influence of perceived treatment difficulty on the outcome of and investment in orthodontic treatment was studied in 19-year-old individuals treated by general practitioners or specialists within the totally subventioned Swedish system for orthodontic care. A total of 313 individuals were evaluated according to treatment outcome and treatment investment. About one-quarter of the treatments evaluated were classified as easy, one-quarter as moderately difficult, and one-half as difficult. The perceived treatment difficulty was on a group basis associated with the pretreatment need. The treatment outcome became less favourable and the treatment investment more expensive the greater the perceived difficulty. More than one-quarter of the treatments provided by general practitioners were classified as difficult compared with three-quarters of those provided by specialists. The outcomes were, in general, more favourable for specialist treatments than for those provided by general practitioners, although the individuals treated by specialists, on the average, were classified as more difficult than those provided by general practitioners. Easy treatments were found to be extremely cost-effective and should be carried out when possible. General practitioners should preferably treat uncomplicated cases, and an increased use of fixed appliances would be desirable in the treatment of moderately difficult treatments. Difficult cases should be treated exclusively by specialists. Cases with little need or benefit of treatment, or a poor prognosis should be given low treatment priority, and patients and parents should in these cases be informed about the small expected benefit and risks involved.

Adolescent↗

PubMed1998

Orthodontic care from the patients' perspective: perceptions of 27-year-olds.

The aim was to analyse 27-year-olds' perceptions of their own dental arrangement and any orthodontic care they may have received as a child or adolescent. All of the individuals in a sample of young adults in Kronoberg County, Sweden, who had received orthodontic care during childhood or adolescence (n = 121) were selected to participate in the study. In addition, 76 orthodontically untreated individuals were randomly selected from the same sample. All participants, both those who had previously had orthodontic treatment and those who had not, were sent a questionnaire. Most of the respondents were satisfied with their earlier decision, whether to choose orthodontic treatment or not. Dental professionals were considered to have had the greatest influence on this decision. This means that the desire for treatment may be guided by the orthodontist. Three out of four individuals considered orthodontic treatment important, even when irregularities of the teeth were minor. A majority of the individuals thought that they would have been able to wear visible braces if needed, even in adulthood. Individuals treated by specialists were more contented than individuals treated by general practitioners. Individuals with malocclusions and treatment need, but who had refused offered treatment, were in general more discontented with their dental arrangement; more than half of them now regretted their decision. They also felt it more difficult to communicate questions, thoughts, and opinions on their own desire for treatment. An increased level of information, especially to these individuals, would have been desirable.

Adult↗

PubMed1998

Hyper-reactive peripheral neutrophils in adult periodontitis: generation of chemiluminescence and intracellular hydrogen peroxide after in vitro priming and FcgammaR-stimulation.

We have earlier reported a higher Fcgamma-receptor (FcgammaR)-mediated generation of reactive oxygen species, measured as luminol-enhanced chemiluminescence (CL) from peripheral neutrophils in adult periodontitis patients. The aims of this study were to confirm our previous results and to elucidate the mechanism of this phenomenon by measuring CL in parallel with the intracellular production of hydrogen peroxide, after stimulation with opsonized bacteria. To determine whether the higher CL was associated with altered responsiveness to priming, the cells were preincubated with tumor necrosis factor alpha (TNFalpha) and lipopolysaccharide (LPS). While CL was significantly higher in subjects with periodontitis, there was no difference in hydrogen peroxide production between the patients and the controls, indicating that the hyperreactivity is related to the generation of other oxygen species than H2O2 and/or to processes in the outer cell membrane. The responsiveness to priming with LPS on CL was slightly but not significantly higher in the periodontitis group, suggesting that priming could be of value for distinguishing subjects with periodontitis. When assaying intracellular production of H2O2, TNFalpha and LPS had both a priming and an activating effect. There were no significant differences between the two groups. In conclusion, this study shows a higher FcgammaR-mediated CL of peripheral neutrophils from adult patients with periodontitis, thus confirming our earlier results. The hyperreactivity seems to be related to the outer cell membrane or to oxygen species other than H2O2.

Adult↗

PubMed1998

Orthodontic treatment demand--differences between urban and rural areas.

OBJECTIVE: To compare the outcome of orthodontic treatment and the desire for further treatment in 19-year-old young adults treated by specialists in urban and rural areas and to study the influence of the level of education of their parents. DESIGN: The individuals were clinically and retrospectively examined with reference to malocclusions and orthodontic treatment received during childhood and adolescence. SETTING: Orthodontic department in Kronoberg County, Sweden. SUBJECTS: From a sample of 302 young adults, all individuals who had received orthodontic treatment by specialists (n = 60) were selected. OUTCOME MEASURES: The individuals were compared according to outcome of treatment and place of residence. The pre-treatment need, the residual treatment need, the treatment results, and the desire for further treatment were estimated as well as treatment duration, number of visits, percentages of discontinued treatments and parents' level of education. RESULTS: There was a higher frequency of individuals without previous treatment and a lower frequency of specialist-treated individuals in rural areas than in urban areas in the county. The treatments implied substantial improvements, with a higher reduction of treatment need and a higher degree of success in patients from urban areas than from rural areas (P < 0.01). There were no statistically significant differences according to gender, socio-economic factors, or desire for further treatment. CONCLUSIONS: The results suggest a greater degree of tolerance towards malocclusions in individuals in rural areas than in urban areas.

Adolescent↗

PubMed1997

Peripheral neutrophils after allergic asthmatic reactions.

The response of peripheral neutrophils was studied in 16 patients with allergic asthma after challenge with birch/grass pollen allergen, in order to identify inflammatory markers associated with only the early asthmatic reaction and those associated with both early and late asthmatic reactions. The allergen challenge proceeded until the patients had an early asthmatic reaction with 100% increase in specific airway resistance. Bronchoconstriction after allergen challenge was monitored hourly over 9 h and finally after 18 h, by measurement of the forced expiratory volume in 1 s. Seven patients had a late reaction, defined as a decrease in forced expiratory volume in 1 s of more than 15%. Blood samples were taken before and 18 h after challenge. After allergen challenge (18 h) the blood concentration of neutrophils in patients with a late asthmatic reaction was 1.4 times higher than before challenge and there was a tendency for increased Fc gamma receptor-mediated chemiluminescence. Lewis X-antigen (CD 15), which is associated with endothelial adhesion and extravasation, significantly decreased at the same time. Neutrophils were incubated with the tetrapeptide arginine-glycine-aspartate-serine before and 18 h after allergen challenge. Both patient groups showed an increased Fc gamma receptor-mediated chemiluminescence and a decreased Fc gamma receptor membrane expression following allergen challenge, suggesting a preactivation. In conclusion, patients with a dual asthmatic reaction show a sustained primed inflammatory response and primed neutrophils compared with patients with only an early reaction when measured after the decline of clinical symptoms provoked by allergen challenge.

Adult↗

PubMed1997

MR imaging of experimental subdural bleeding. Correlates of brain deformation and tissue water content, and changes in vital physiological parameters.

PURPOSE: To evaluate morphological and physiological changes during acute lethal subdural bleeding in 2 models of anaesthetized dogs. MATERIAL AND METHODS: In model I, blood from the aorta was led into a collapsed subdural rubber balloon while in model II, the blood was directed into the subdural compartment over the left cerebral frontoparietal lobe. Eight vital physiological parameters were continuously registered. MR imaging visualized the compression and displacement of cerebral tissue, and assessed the dynamic changes in cerebral tissue water. RESULTS: In model I, tissue herniation and compression of cerebral ventricles led to death at a haematoma volume corresponding to 8% of the intracranial volume. In model II, the extravasated blood progressed infratentorially and into the spinal sac with a volume that was 3 times larger than that of the lethal haematoma. Tissue water increased almost linearly during bleeding in both models. CONCLUSION: The high level of mortality after acute subdural haematoma is caused by a reduction in intracranial volume tolerance with a critical decrease in cerebral perfusion pressure, resulting in a fatal cerebral ischaemia.

Animals↗

PubMed1997

Gingival crevicular neutrophils: membrane molecules do not distinguish between periodontitis and gingivitis.

We have earlier reported hyperreactive peripheral neutrophils in adult periodontitis, measured as respiratory burst after Fc gamma receptor-mediated activation in vitro, but we have not been able to relate this increased activity to aberrations in the expression of relevant membrane molecules. Various types of inflammatory conditions involving the gingiva should affect membranes differently. We therefore collected crevicular neutrophils from three types of inflammatory sites: (i) with and (ii) without tissue destruction in the same periodontitis patients and (iii) inflamed sites in controls with gingivitis alone and compared the expression of membrane molecules by flow cytometry. The % of positively stained cells and their mean intensities of fluorescence (IFL) were similar in the three types of sites for CD15, CD11a, CD11b and CD16. Peripheral neutrophils studied with the same markers were not activated. This was verified by similar plasma concentrations of lactoferrin and L-selectins in the periodontal and control groups. Compared to peripheral cells, the crevicular neutrophils showed a significantly lower percentage of stained cells, while the stained cells increased their IFL. In conclusion, hyperreactive peripheral neutrophils in periodontitis show the same expression of membrane molecules after migration through different types of inflammatory lesions as do normal neutrophils in gingivitis.

Adult↗