PubMed Health⌕ Search

Biomedical subjects

C Olsson

Publications and source records attributed to C Olsson.

At least 19 recordsLinked to original sources
PubMed2005

Research utilization among dental hygienists in Sweden--a national survey.

Over the last decade evidence-based practice has become increasingly important in health care as an approach to improve patient outcomes. It is vital that dental hygienists, like other health professionals, use research findings to inform clinical practice. The objective of the present study was to investigate the extent of research utilization among dental hygienists in Sweden and to investigate the relationship between level of education and factors related to research utilization. A random sample of 261 dental hygienists in Sweden, 113 with 1 year and 148 with 2-year education, responded to a postal questionnaire covering various aspects of research utilization, i.e. their attitudes towards research, availability and support for the implementation of research findings, use of research in daily practice, their activity in seeking new research findings and their participation in a range of research-related activities. Dental hygienists with 2-year education had a more positive attitude towards research, used research to a greater extent and were more active in seeking new research findings than dental hygienists with 1-year education. Overall, relatively few dental hygienists reported that they implemented research findings in practice; the most frequently reported activity concerned reading research articles in professional journals. The conclusions are that the length of dental hygiene education is a key factor influencing the application of research findings to practice. One-year education appears to be inadequate to achieve evidence-based practice. Moreover, not even two years of formal education guarantees necessary competence in research for evidence-based dental hygiene practice.

Adult↗
PubMed2004

Increased fragility in patients with fracture of the proximal humerus: a case control study.

The aim of this study was to evaluate whether a fracture of the proximal humerus is associated with an increased prevalence of preceding fractures or a risk of subsequent fractures. All patients who were treated at the Malmö General Hospital in 1987 for a fresh fracture of the proximal humerus were identified, representing practically all fractures of the proximal humerus in Malmö city (250,000) that year. Two hundred fifty-three adult patients, 54 men with an average age of 66 (24-90) and 199 women with a mean age of 74 (22-98) years, were included in the study together with 475 age- and gender-matched control persons. In 1999, fracture prevalence of patients and controls were rated by a survey at the Dept. of Radiology. There was a significantly increased prevalence of previous fractures before 1987 in the humerus fracture group with an odds ratio (OR) of 3.5 [95% confidence interval (95% CI), 2.2-5.5] for a spinal fracture, OR 1.8 (95% CI, 1.3-2.6) for a previous fracture to the upper extremity, and OR 1.8 (95% CI, 1.2-2.6) for a preceding fracture of the lower limb. The proximal humerus fracture also predicted a significantly increased risk of a subsequent fracture. The hazard ratio (HR) was 2.5 (95% CI, 1.7-3.7) for a forthcoming spinal fracture, HR 2.8 (95% CI, 2.0-3.7) for a future fracture of the upper extremity, and HR 2.0 (95% CI, 1.2-3.5) for a lower limb fracture. In a subgroup of male patients, an almost five times increased risk of sustaining subsequent extremity fractures was observed. In summary, a fracture of the proximal humerus is associated both with increased prevalence of previous fractures of the spine and extremities and also predicting an increased risk of future fractures.

Adult↗
PubMed2004

Submerged or non-submerged healing of endosseous implants to be used in the rehabilitation of partially dentate patients.

OBJECTIVE: To evaluate bone-level alterations that occurred at implants of the Astra Tech(R) System that were placed in the load carrying, posterior parts of the dentition using either a submerged (two-stage) or a non-submerged (one-stage) installation protocol. MATERIAL AND METHODS: Eighty-four patients that required 115 fixed partial dentures (FPDs or cases) entered the prospective study. All subjects were assigned one patient and > or =one case numbers. For the randomization of cases, a custom-made program based on balanced random permuted blocks was utilized. The cases were assigned to two treatment groups, namely one-stage installation procedure, non-submerged technique (group A) and two-stage installation procedure, submerged technique (group B). Several subjects contributed with cases to both groups A and B. Periodontal, endodontal and open caries lesions were treated prior to implant installation. All patients received careful oral hygiene instruction and training in self-performed plaque control measures. The surgical technique used for fixture installation followed the outline described in the manual for the Astra Tech System. The FPDs were placed 3 months (mandible) and 6 months (maxilla) following implant installation. Immediately following FPD placement, a baseline examination was performed that included assessment of plaque, soft-tissue inflammation and bone level. Clinicians who were otherwise not involved in the study performed the radiographic measurements. Clinical and radiographical examinations were repeated once a year after the baseline examination. DATA ANALYSIS: The primary outcome variable was the change in the bone level at the implants from the time of placement of the bridge (FPD) to the 1- and 2-year reexaminations. Fisher's permutation test was used to test if differences existed between groups A and B, and between patients (men/women, smokers/non-smokers, age), sites (maxilla/mandible) and implants (length, diameter). Pitman's test was used to study correlations between bone shape and quality data and different radiographic bone-level data. RESULTS: It was demonstrated that tissue healing following implant installation appeared to be independent of the surgical protocol, i.e. whether the marginal portions of the implants during surgery were fully or only partly submerged under the ridge mucosa. Thus, (i) in both treatment groups the number of implants that failed to osseointegrate (early failures) was small (<2%); (ii) at the end of the recommended periods of bone healing prior to loading, - in both groups, maxilla=6 months and mandible=3 months - the level of the marginal bone was close to the coronal rim of the fixture; group A: 1.54+/-0.92 mm, group B: 1.31+/-0.77 mm. The current study also demonstrated that irrespective of surgical protocol (two-stage, one-stage), implants supporting the FPDs exhibited only small amount of radiographic bone loss during the first year of function (group A: 0.02+/-038 mm, group B: 0.17+/-0.64 mm). Moreover, during the second year of function, the amount of additional bone loss that occurred in the two treatment groups was close to zero. CONCLUSION: Periimplant bone-level change during function seemed to be unrelated to whether initial soft- and hard-tissue healing following implant installation had occurred under submerged or non-submerged conditions.

Adult↗
PubMed2003

The Yersinia HPI is present in Serratia liquefaciens isolated from meat.

AIMS: The aim of the study was to screen the Enterobacteriaceae flora of meat for the presence of bacteria harbouring the Yersinia high-pathogenicity island (HPI). METHODS AND RESULTS: Bacteria from 29 meat and 29 liver samples were isolated on violet-red bile glucose agar. A total of 197 isolates were screened for the presence of the irp2 gene, encoded within the HPI, by PCR. One isolate that was positive for irp2 gene was also positive for the fyuA, irp1, ybtP/ybtQ, ybtX/ybtS and int/asn tRNA genes by PCR. The presence of fyuA, irp1 and irp2 genes was confirmed by Southern hybridization. CONCLUSIONS: The isolate was identified as Serratia liquefaciens by sequencing of the 16S rRNA gene and by ribotyping. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first report of a Serratia harbouring the Yersinia HPI. Serratia is a frequently occurring Enterobacteriaceae genus in chill-stored meat.

Animals↗
PubMed2003

General anaesthesia or conscious sedation for painful procedures in childhood cancer: the family's perspective.

BACKGROUND: Until recently, midazolam sedation was routinely used in our institution for bone marrow aspirates and lumbar punctures in children with cancer. It has been perceived by many doctors and nurses as being well tolerated by children and their families. AIM: To compare the efficacy of inhalational general anaesthesia and midazolam sedation for these procedures. METHODS: A total of 96 children with neoplastic disorders, who received either inhalational general anaesthesia with sevoflurane, nitrous oxide, and oxygen (GA) or sedation with oral or nasal midazolam (SED) as part of their routine preparation for procedures were studied. The experiences of these children were examined during their current procedure and during their first ever procedure. Main outcome measures were the degree of physical restraint used on the child, and the levels of distress and pain experienced by the child during the current procedure and during the first procedure. The family's preference for future procedures was also determined. RESULTS: During 102 procedures under GA, restraint was needed on four occasions (4%) when the anaesthetic mask was first applied, minimal pain was reported, and children were reported as distressed about 25% of the time. During 80 SED procedures, restraint was required in 94%, firm restraint was required in 66%, the child could not be restrained in 14%, median pain score was 6 (scale 0 (no pain) to 6 (maximum pain)), and 90% of the parents reported distress in their child. Ninety per cent of families wanted GA for future procedures. Many families reported dissatisfaction with the sedation regime and raised concerns about the restraint used on their child. CONCLUSIONS: This general anaesthetic regime minimised the need for restraint and was associated with low levels of pain and distress. The sedation regime, by contrast, was much less effective. There was a significant disparity between the perceptions of health professionals and those of families with respect to how children coped with painful procedures.

Adolescent↗
PubMed2002

Unexpectedly high allelic diversity at the KIT locus causing dominant white color in the domestic pig.

Mutations in KIT encoding the mast/stem cell growth factor receptor (MGF) are responsible for coat color variation in domestic pigs. The dominant white phenotype is caused by two mutations, a gene duplication and a splice mutation in one of the copies leading to skipping of exon 17. Here we applied minisequencing and pyrosequencing for quantitative analysis of the number of copies with the splice form. An unexpectedly high genetic diversity was revealed in white pigs. We found four different KIT alleles in a small sample of eight Large White females used as founder animals in a wild boar intercross. A similar number of KIT alleles was found in commercial populations of white Landrace and Large White pigs. We provide evidence for at least two new KIT alleles in pigs, both with a triplication of the gene. The results imply that KIT alleles with the duplication are genetically unstable and new alleles are most likely generated by unequal crossing over. This study provides an improved method for genotyping the complicated Dominant white/KIT locus in pigs. The results also suggest that some alleles may be associated with negative pleiotropic effects on other traits.

Alleles↗
PubMed2001

Autonomic dysfunction and ambulatory blood pressure in renal transplant recipients.

BACKGROUND: Abnormal circadian blood pressure (BP) rhythm (nondipping) and autonomic dysfunction are both common in end-stage renal disease (ESRD). It is not known whether these abnormalities are related or if they are associated with greater left ventricular hypertrophy. METHODS: Nineteen renal transplantation (RT) recipients, aged 22-67 years, who were transplanted at least 12 months (1-29 years) previously, were studied with 24-hr ambulatory blood pressure monitoring (ABPM). Autonomic function was tested by automated analysis of heart rate variations and echocardiography was used to estimate left ventricular mass index (LVMI). RESULTS: Thirteen patients (68%) were nondippers. Although seven (37%) patients had significant parasympathetic dysfunction, this was not related to dipper status. Neither abnormality showed a tendency to diminish with time after RT. Systolic hypertension, diagnosed by ABPM, occurred in 5% of patients during the awake period and in 52% during sleep, whereas diastolic hypertension occurred in 47% when awake and in 63% when asleep. Awake systolic BP was the strongest predictor of LVMI (r=0.7, P<0.001), and was considerably better than systolic BPs recorded at the clinic (r=0.48, P<0.05). CONCLUSIONS: Nondipping is common after RT but is not related to the degree of autonomic dysfunction. These findings suggest that autonomic dysfunction is not a major contributor to nondipping in ESRD. In RT patients, ABPM is a more sensitive measure of hypertension and a stronger predictor of LVMI than clinic BP.

Adolescent↗
PubMed2001

Increased transcription levels induce higher mutation rates in a hypermutating cell line.

Somatic hypermutation, in addition to V(D)J recombination, is the other major mechanism that generates the vast diversity of the Ab repertoire. Point mutations are introduced in the variable region of the Ig genes at a million-fold higher rate than in the rest of the genome. We have used a green fluorescent protein (GFP)-based reversion assay to determine the role of transcription in the mutation mechanism of the hypermutating cell line 18-81. A GFP transgene containing a premature stop codon is transcribed from the inducible tet-on operon. Using the inducible promoter enables us to study the mutability of the GFP transgene at different transcription levels. By analyzing stable transfectants of a hypermutating cell line with flow cytometry, the mutation rate at the premature stop codon can be measured by the appearance of GFP-positive revertant cells. Here we show that the mutation rate of the GFP transgene correlates with its transcription level. Increased transcription levels of the GFP transgene caused an increased point mutation rate at the premature stop codon. Treating a hypermutating transfection clone with trichostatin A, a specific inhibitor of histone deacetylase, caused an additional 2-fold increase in the mutation rate. Finally, using Northern blot analysis we show that the activation-induced cytidine deaminase, an essential trans-factor for the in vivo hypermutation mechanism, is transcribed in the hypermutating cell line 18-81.

Animals↗
PubMed2001

Heteroplasmy of the human mtDNA control region remains constant during life.

In a longitudinal, retrospective study, we monitored the level of heteroplasmy at nucleotide position (nt) 309 and nt 16189 of the control region of human mtDNA. As a unique source of DNA, we analyzed multiple cervical-cell samples collected, during 1 or 2 decades, from four women with heteroplasmy at either nt 309 or nt 16189. According to accurate, quantitative analysis by solid-phase minisequencing, the level of heteroplasmy remained stable in the cervical-cell samples from all four women during the time studied. We also analyzed autopsy samples from several different tissues, all containing nt 309 in heteroplasmic form, of one of the women, who was deceased. On the basis of our results, heteroplasmy in the control region of mtDNA seems to be inherited and is not the result of somatic age-related accumulation.

Autopsy↗
PubMed2001

Nitric oxide, a potent vasodilator of the aortic anastomosis in the estuarine crocodile, Crocodylus porosus.

The effects of five neuropeptides (CGRP, SOM, SP, NPY, VIP), L-NAME (nitric oxide synthase inhibitor), and adrenaline on the contractile tone of the aortic anastomosis in the estuarine crocodile, Crocodylus porosus, were investigated. None of the neuropeptides, which had previously been found to be present in the aortic anastomosis, had any direct effect on the tension developed by ring preparations. L-NAME itself significantly increased the basal tone of the vascular ring preparations, suggesting a tonic release of nitric oxide in the preparation. Adrenaline produced concentration-dependent vasoconstrictions that were counteracted by profound reflex vasodilatations that were susceptible to blockade by L-NAME. Immunohistochemistry revealed the presence of nitric oxide synthase and tyrosine hydroxylase-containing (indicating the presence of a adrenergic innervation) nerve fibres in the adventitia and adventitio-medial border of the aortic anastomosis. These data demonstrate opposing actions of adrenaline and nitric oxide on the vascular smooth muscle in the anastomosis of the C. porosus. The morphology of the anastomosis, with the extremely thick muscular vessel wall, suggests a sphincter-like function for this vessel that could be controlled mainly by adrenergic and nitrergic mechanisms.

Alligators and Crocodiles↗
PubMed2001

The control of gut motility.

Gut motility in non-mammalian vertebrates as in mammals is controlled by the presence of food, by autonomic nerves and by hormones. Feeding and the presence of food initiates contractions of the stomach wall and subsequently gastric emptying, peristalsis, migrating motor complexes and other patterns of motility follow. This overview will give examples of similarities and differences in control systems between species. Gastric receptive relaxation occurs in fish and is an enteric reflex. Cholecystokinin reduces the rate of gastric emptying in fish as in mammals. Inhibitory control of peristalsis is exerted, e.g. by VIP, PACAP, NO in fish and amphibians, while excitatory stimuli arise from nerves releasing tachykinins, acetylcholine or serotonin (5-HT). In crocodiles, we have found the presence of the same nerve types, although the effects on peristalsis have not been studied. Recent studies on signal transduction in the gut smooth muscle of fish and amphibians suggest that external Ca2+ is of great importance, but not the only source of Ca2+ recruitment in tachykinin-, acetylcholine- or serotonin-induced contractions of rainbow trout and Xenopus gastrointestinal smooth muscle. The effect of acetylcholine involves reduction of cAMP-levels in the smooth muscle cells. It is concluded that, in general, the control systems in non-mammalian vertebrates are amazingly similar between species and animal groups and in comparison with mammals.

Animals↗
PubMed2001

The level of the mitochondrial mutation A3243G decreases upon ageing in epithelial cells from individuals with diabetes and deafness.

We have in a longitudinal study determined the proportion of the mitochondrial A3243G mutation in DNA obtained from cervical cell samples collected from three individuals affected with mitochondrial diabetes and hearing loss during a period of up to 18 years. Using the minisequencing method we were able to sensitively determine the proportion between mutant and normal mitochondrial DNA. Our results demonstrate a constant decrease in the levels of the pathogenic mutation in mitotic tissues of affected individuals with time.

Adult↗
PubMed2000

Mouse genetics/genomics: an effective approach for drug target discovery and validation.

The mouse has become the premier mammalian system for the identification of the genetic basis of both mono- and oligogenic disorders, as well as the understanding of complex diseases with gene-gene and gene-environment interactions. The similarity between human and mouse genetic disease is sometimes striking, while in other cases the phenotypes are less similar. The ability to genetically map and then clone single gene disorders rapidly, and the emerging technologies that will allow the economical identification of the polygenes controlling quantitative traits further demonstrate the utility of the mouse as a model for gene discovery. Additionally, the ability to genetically manipulate the mouse through transgenesis and gene targeting allows for the testing of hypotheses regarding specific gene function and their role in disease. The utility of the mouse extends beyond being just a gene discovery tool to provide prevalidated targets. It can also be used for the development of animal models, and the testing of compounds in specifically constructed transgenic and knockout strains to further define the target and pathway of a therapeutic compound.

Amino Acid Sequence↗
PubMed2000

An in vitro study of fluoride release from a resin-modified glass ionomer cement after exposure to toothpaste slurries of different pH.

The aim of the study was to evaluate the fluoride release from an aged resin-modified glass ionomer (Vitremer) after exposure to five toothpaste slurries with different pH values. Cylindrical specimens of the material were leached in de-ionized water for 3 months and then exposed for 30 min daily for 10 days to three dentifrice slurries (20 specimens/group) containing 0.05% fluoride with pH values of 2.6, 5.7 and 8.3 and two non-fluoridated slurries with pH values of 2.5 and 5.7. A neutral NaF solution (0.05% F) was used as a control. During the 30 min exposure time, the fluoride concentration was gradually decreased in order to imitate the clinical situation. Thereafter, specimens were immersed individually in de-ionized water and the fluoride release determined. After the first day of exposure, all groups except one without fluoride (pH 5.7) showed significantly (P < 0.05) increased fluoride release. After exposure to the fluoridated toothpaste slurry with pH 5.7, significantly (P < 0.05) more fluoride was released compared to the toothpaste slurry with pH 8.3. Low pH (2.5 or 2.6) of the slurry resulted in a significantly (P < 0.05) higher fluoride release, regardless of whether it was fluoridated or not. The total amount of fluoride released after exposure to the more acidic fluoride toothpaste slurry was greater than that released from the more acidic non-fluoride toothpaste and the less acidic fluoride toothpaste. Our data indicate that the fluoride release from the resin-modified glass ionomer studied may be increased after treatment with an acidified NaF-toothpaste.

Analysis of Variance↗
PubMed2000

No benefit of reduced heparinization in thoracic aortic operation with heparin-coated bypass circuits.

BACKGROUND: Heparin coating of the cardiopulmonary bypass circuit attenuates inflammatory response and confer clinical benefits in cardiac operations. The positive effects may be amplified with reduced systemic heparin dosage. We studied markers of inflammation and coagulation in thoracic aortic operations with heparin-coated circuits and standard vs reduced systemic heparinization. METHODS: Thirty patients were randomized to standard (group S; 300 IU/kg initially; activated clotting times [ACT] > 480 seconds; 5,000 IU in prime; n = 16) or reduced (group R; 100 IU/kg initially; ACT > 250 seconds; 2,500 IU in prime; n = 14) dose systemic heparin. The following markers were analyzed perioperatively: (a) inflammatory response; acute phase cytokine interleukin-6, and granulocytic proteins myeloperoxidase and lactoferrin; (b) complement activation; factor C3a and the C5a-9 terminal complement complex [TCC]; and (c) coagulation; thrombin-antithrombin III complex. RESULTS: The clinical outcome did not differ between groups. Four (29%) patients in group R had a perioperative thromboembolic event. All studied markers were significantly elevated during and throughout cardiopulmonary bypass in both groups. Maximal values were higher in group R for all variables except for TCC. There were no statistically significant intergroup differences regarding markers of inflammation, complement activation, or coagulation activation. CONCLUSIONS: The blood trauma in thoracic aortic operation is extensive, as reflected by the elevation of the studied biochemical markers, even when heparin-coated cardiopulmonary bypass circuits are used. In this study, we did not detect any benefits, either biochemical or clinical, of reducing the dose of systemic heparin.

Aged↗