Biomedical subjects

P Kallio

Publications and source records attributed to P Kallio.

At least 19 recordsLinked to original sources

PubMed2001

UDP-galactose transporter is required for Theiler's virus entry into mammalian cells.

Theiler's murine encephalomyelitis viruses (TMEV) are divided into two groups: high-neurovirulence strains, such as GDVII, cause fatal encephalitis, while low-neurovirulence strains, such as BeAn and DA, cause persistent infection and demyelination in mice. Cell surface sialic acid is bound by the low-neurovirulence DA and BeAn viruses, but not by the high-neurovirulence GDVII virus. We have identified a clone from a BHK-21 cell cDNA library that mediates TMEV entry and infection by viruses of both TMEV groups in a receptor-negative BHK-21 cell variant (R26). The sequence of this clone is 96.4% identical to the human UDP-galactose transporter (UGT), which belongs to a family of nucleotide-sugar transporter proteins involved in the biosynthesis of complex carbohydrate structures in the trans-Golgi network. UGT mRNA from R26 cells was found to have a 490-nucleotide deletion involving the C-terminal amino acids 255 to 392 and 81 nucleotides of the 3' noncoding region. These results suggest two possibilities by which UGT may mediate TMEV entry and infection. The most likely one relates to the transporter function of adding galactose to another receptor protein. This possibility suggests the requirement for a specific glycoprotein interaction for GDVII virus cell binding and entry, e.g., galactose for GDVII and sialic acid for BeAn. Alternatively, UGT might be a TMEV receptor itself, acting via UGT cycling to the cell surface.

Amino Acid Sequence↗

PubMed2001

MRI abnormalities of foot and ankle in asymptomatic, physically active individuals.

OBJECTIVE: To assess MRI changes in the ankle and foot after physical exercise. DESIGN AND PATIENTS: Nineteen non-professional marathon runners and 19 age- and sex-matched controls volunteered for the study. All had ankle and foot MR images (1.5 T) taken in three perpendicular planes (STIR, T2F and T1FS sequences) within 3 h of running a full-length marathon (42.125 km). Three radiologists independently analysed the groups on a masked basis using a predefined form. RESULTS: Severe bone marrow oedema was seen in one and slight bone marrow oedema in three marathon runners. Slight bone marrow oedema was found in three control subjects. Signal alteration within the soleus muscle, consistent with a grade 1 strain, was found in one marathon runner. Small punctate hyperintensities within the Achilles tendon were seen in 26% of the marathon runners and in 63% of controls (P = 0.016). An increased amount of fluid in the retrocalcaneal bursa was found in one control and in none of the marathon runners. Small amounts of fluid in the retrocalcaneal bursa were seen in 68% of marathon runners and in 53% of controls. Grade 1 or 2 peritendinous joint fluid was found around 22% of tendons, among both marathon runners and controls, most often involving the tendon sheath of the flexor hallucis longus muscle. An increased amount of joint fluid was noted in 34% of the joints of the marathon runners, and in 18% of the controls. CONCLUSION: MRI shows several abnormalities in the ankle and foot both after marathon races and in asymptomatic physically active individuals without any preceding extraordinary strain. Recreational sports may lead to a number of positive MRI findings without correlation with clinical findings.

Adult↗

PubMed2001

Acute paediatric ankle trauma: MRI versus plain radiography.

OBJECTIVE: To evaluate the diagnosis of acute physeal ankle fractures on plain radiographs using MRI as the gold standard. METHODS: Sixty consecutive children, 29 with a clinical diagnosis of lateral ligament injury and 31 with physeal ankle fractures, were examined using both radiographs and MRI in the acute period. The imaging data were reviewed by three "masked" radiologists. The fracture diagnosis and Slater-Harris classification of radiographs were compared with findings on MRI. RESULTS: Plain radiography produced five of 28 (18%) false negative and 12 of 92 (13%) false positive fracture diagnoses compared with MRI. Six of the 12 false positive fractures were due to a misclassification of lateral ligament disruption as SH1 fractures, Altogether a difference was found in 21% of cases in either the diagnosis or the classification of the fractures according to Salter-Harris. All bone bruises in the distal tibia and fibula and 64% of bone bruises in the talus were seen in association with lateral ligament injuries. Talar bone bruises in association with fractures occurred on the same side as the malleolar fracture; talar bone bruises in association with lateral ligament disruption were seen in different locations. The errors identified on radiographs by MRI did not affect the management of the injury. CONCLUSIONS: The incidence of false negative ankle fractures in plain radiographs was small and no complex ankle fractures were missed on radiographs. The total extent of complex fractures was, however, not always obvious on radiographs. In an unselected series of relatively mild ankle injuries, we were unable to show a single case where the treatment or prognosis based on plain radiography should have been significantly altered after having done a routine MRI examination. Plain radiography is still the diagnostic cornerstone of paediatric ankle injuries.

Acute Disease↗

PubMed2001

One-year compliance and effects of amine and stannous fluoride on some salivary biochemical constituents and oral microbes in institutionalized elderly.

Due to old age and poor general health, the institutionalized elderly have often not been used as research subjects for the investigation of oral health protocols. Because the number of elderly is increasing, they are an important target group for the development of oral hygiene aids. This trial was designed to investigate whether the institutionalized elderly could successfully use an amine-fluoride- and stannous-fluoride-containing mouthwash and toothpaste during a 12-month period. A dental hygienist visited the subjects weekly, instructed them, and recorded their self-reported compliance. Plaque and saliva samples were taken at three-month intervals. Some salivary biochemical constituents reflecting mucosal integrity were analyzed. The carrier status of Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Bacteroides forsythus, Prevotella intermedia, and Prevotella nigrescens was studied by the polymerase chain-reaction method, and acidogenic bacteria and yeasts by dip-slide methods (Orion Diagnostica, Espoo, Finland). Of those 98 subjects originally included, 44 elderly (30 women and 14 men; mean age, 81.7 +/- 5.9 yrs) completed the trial. Their observations were positive or very positive regarding the use of mouthwash and toothpaste. The number of residents with P. gingivalis decreased statistically significantly throughout the trial, while the carrier status of the other periodontal bacteria and mutans streptococci remained on the same level. The number of subjects with high counts (> or = 10(5) cfu/mL) of yeasts decreased during the study: 26.2% at baseline, 9.1% one year later, respectively. Biochemical analyses of salivary immunoglobulins showed no effect on IgA and IgM levels, but IgG reduced significantly. Albumin and other salivary protein concentrations were found to have a decreasing tendency. Thus, the overall effect of the protocol was beneficial with regard to subjects' oral health as measured in this study. The residents were pleased to participate, but the number of drop-outs was very high, confirming the expected difficulties with the utilization of a group of frail elderly as research subjects.

Aged↗

PubMed2001

High numbers of viral RNA copies in the central nervous system of mice during persistent infection with Theiler's virus.

The low-neurovirulence Theiler's murine encephalomyelitis viruses (TMEV), such as BeAn virus, cause a persistent infection of the central nervous system (CNS) in susceptible mouse strains that results in inflammatory demyelination. The ability of TMEV to persist in the mouse CNS has traditionally been demonstrated by recovering infectious virus from the spinal cord. Results of infectivity assays led to the notion that TMEV persists at low levels. In the present study, we analyzed the copy number of TMEV genomes, plus- to minus-strand ratios, and full-length species in the spinal cords of infected mice and infected tissue culture cells by using Northern hybridization. Considering the low levels of infectious virus in the spinal cord, a surprisingly large number of viral genomes (mean of 3.0 x 10(9)) was detected in persistently infected mice. In the transition from the acute (approximately postinfection [p.i.] day 7) to the persistent (beginning on p.i. day 28) phase of infection, viral RNA copy numbers steadily increased, indicating that TMEV persistence involves active viral RNA replication. Further, BeAn viral genomes were full-length in size; i.e., no subgenomic species were detected and the ratio of BeAn virus plus- to minus-strand RNA indicated that viral RNA replication is unperturbed in the mouse spinal cord. Analysis of cultured macrophages and oligodendrocytes suggests that either of these cell types can potentially synthesize high numbers of viral RNA copies if infected in the spinal cord and therefore account for the heavy viral load. A scheme is presented for the direct isolation of both cell types directly from infected spinal cords for further viral analyses.

Animals↗

PubMed2000

The in vivo expression of the collagenolytic matrix metalloproteinases (MMP-2, -8, -13, and -14) and matrilysin (MMP-7) in adult and localized juvenile periodontitis.

Periodontal inflammation is characterized by irreversible degradation of periodontal ligament collagen fibers leading to loss of tooth attachment. Cultured gingival keratinocytes and fibroblasts express, in vitro, various matrix metalloproteinases (MMPs) which can degrade fibrillar collagens. We hypothesized that several MMPs are also synthesized in vivo by sulcular epithelium, and analyzed the collagenolytic MMPs (MMP-2, -8, -13, and -14) and matrilysin (MMP-7) in gingival tissue specimens and gingival crevicular fluid from adult and localized juvenile periodontitis patients by in situ hybridization, immunohistochemistry, and Western immunoblotting. MMP-2, -7, -8, and -13 were expressed in gingival sulcular epithelium. MMP-7 and -13 were also located in fibroblasts and macrophages, and MMP-8 in neutrophils. MMP-8- and -13-positive cells/mm2 were higher in periodontitis gingiva when compared with healthy control tissue (p < 0.01). In periodontal diseases, gingival sulcular epithelium expresses several, rather than a single, collagenolytic MMPs, and this proteolytic cascade is evidently responsible for the tissue destruction characteristic of adult and juvenile periodontitis.

Adolescent↗

PubMed1999

Scientific basis of a matrix metalloproteinase-8 specific chair-side test for monitoring periodontal and peri-implant health and disease.

Matrix metalloproteinases (MMPs), especially collagenase-2 (MMP-8), are key mediators of irreversible tissue destruction associated with periodontitis and peri-implantitis. MMP-8 is known to exist in elevated amounts and in active form in the gingival crevicular fluid (GCF) and peri-implant sulcular fluid (PISF) from progressing periodontitis and peri-implantitis lesions and sites, respectively. (Sorsa et al. Ann. N.Y. Acad. Sci. 737: 112-131 [1994]; Teronen et al. J. Dent. Res. 76: 1529-1537 [1997]). We have developed monoclonal antibodies to MMP-8 (Hanemaaijer et al. J. Biol. Chem. 272: 31504-31509 [1997]) that can be used in a chair-side dipstick test to monitor the course and treatment of periodontitis and peri-implantitis. Monoclonal and polyclonal antibody tests for MMP-8 coincided with the classical functional collagenase activity test from GCF and PISF (Sorsa et al. J. Periodont. Res. 22: 386-393 [1988]) in periodontal and peri-implant health and disease. In future a chair-side functional and/or immunological MMP-test can be useful to diagnose and monitor periodontal and peri-implant disease and health.

Antibodies↗

PubMed1999

Conservative treatment of scaphoid fractures: a follow up study.

BACKGROUND AND AIMS: This investigation was made to elucidate the outcome of conservatively treated scaphoid fractures. MATERIAL AND METHODS: 63 patients with a scaphoid fracture were treated initially conservatively and examined retrospectively. The mean follow up time was 54 months. RESULTS: In this group bone union was achieved in 56 cases (89%). Three of the patients ended up to operation because of delayed union soon after conservative treatment and three nonunions were found in the follow up appointment. One fracture did not heal because of dislocation during cast treatment and was treated with operation. Incidence of osteoarthrosis and residual symptoms were studied in the group with totally conservative treatment. Osteoarthrosis was found in 19 (32%) wrists, but no correlation with wrist problems (pain, reduced grip strength or problems at work) was found. 20 (34%) of the patients complained residual symptoms. Most of the symptoms were mild and did not impair their ability to work or cause serious problems during free time. CONCLUSION: According to the present study conservative treatment is a safe method for the treatment of undislocated stabile scaphoid fractures.

Adolescent↗

PubMed1998

Soluble CD27 in thyroid disorders.

We measured the soluble cytokine CD27 in a variety of thyroid disorders. Soluble CD27 was increased in untreated Graves' hyperthyroidism and in euthyroid ophthalmopathy. Levels of sCD27 were normal after the establishment of euthyroidism with propylthiouracil (PTU) or radio iodine in primary hypothyroidism, chronic thyroiditis, and the hyperthyroid and euthyroid phases of subacute thyroiditis. Soluble CD27 is a marker for cellular activation as in Graves' hyperthyroidism, but it is not predictive of the outcome of PTU therapy.

Acute Disease↗

PubMed1998

Comparative genomic hybridization of low-grade central osteosarcoma.

Very little is known concerning the cytogenetic and molecular genetic changes of low-grade central osteosarcoma, a rare form of osteosarcoma. In the present study, we used comparative genomic hybridization (CGH) to screen for DNA sequence copy number aberrations in 10 samples from 6 patients: 7 typical low-grade central osteosarcomas, one low-grade (Grade II) central osteosarcoma, and two high-grade (III and IV) local recurrences of a low-grade central osteosarcoma Nine samples had aberrations. Six typical low-grade central osteosarcoma samples had a single DNA sequence copy number change per tumor. Three samples from more advanced tumors (a Grade II low-grade central osteosarcoma and local recurrences of Grade III and IV) had a mean of five changes per tumor. Recurrent changes affected these minimal common regions: +12q13-q14 (three tumors), +12p (two tumors), and +6p21.1-p21.3 (two tumors). Nine samples were analyzed for CDK4 and MDM2 expression and SAS amplification. One sample with a gain of chromosome 12 had a very strong expression of MDM2, strong expression of CDK4, and amplification of SAS. One sample with a gain of 12q13-q14 had strong expression of CDK4 and MDM2. Strong expression of CDK4 was found in two additional tumors; one had a gain of 12q13-q21, and the other had no changes in chromosome 12 by CGH. No alterations were detected in the CDK4, MDM2, and SAS panel in three other samples with no changes in chromosome 12 by CGH. In conclusion, the low number of DNA sequence copy number alterations reflects the relatively low malignancy of low-grade central osteosarcoma. This simplicity differs from the complex aberrations seen in conventional high-grade osteosarcomas.

Adolescent↗

PubMed1997

Assessment of the effect of an oscillating/rotating electric toothbrush on oral health. A 12-month longitudinal study.

The aim of this 12-month parallel design controlled clinical trial was to assess the effect of the Braun Oral-B Plak Control electric toothbrush on supragingival plaque and gingival health, and to compare it with a conventional soft manual toothbrush (Jordan). A total of 111 patients aged between 20 and 63 years, from a general population, with bleeding on probing at 30% or more of all sites examined were entered into the study. At baseline, immediately after periodontal examination, all volunteers received a thorough scaling of their teeth. Volunteers in both groups were told to brush their teeth for 2 min 2 x a day. Oral hygiene instruction was given at the start of the study and was not repeated. At 3, 6 and 12 months, assessments were carried out by a single clinician who was not aware which group the volunteers belonged to. Analysis of results demonstrated that over the 12 months of the study, the Braun Oral-B Plak Control was significantly more effective in improving gingival health than the manual toothbrush. There was, however, no difference between the 2 groups in terms of plaque removal, with the number of sites with visible plaque decreasing by a similar amount in both groups. In conclusion, results indicate that the Braun Oral-B Plak Control toothbrush is safe and more effective than a manual toothbrush in improving gingival health.

Adult↗

PubMed1997

Occlusal restorative decisions based on visual inspection--calibration and comparison of different methods.

The purpose of this in vitro study was to calibrate occlusal restorative decision-making based on visual inspection (VI), and to compare it with visual inspection with magnifying (x1.25) lenses (VIM), and fibre-optic transillumination (VIF). Sixty extracted human third molars mounted in plaster were examined using VI by ten dentists three times during the calibration process. After wash-out periods, the teeth were re-examined by the same dentists using VI, VIM and VIF. The inter-examiner reproducibility for VI, expressed as Kappa (kappa) statistics (kappa +/- SD), was 0.46 +/- 0.10 before and 0.59 +/- 0.11 after the calibration process and remained at the same level after the wash-out period. Intra-examiner reproducibility was substantially higher for VI (kappa -0.68 +/- 0.15) before and after the wash-out period. There were no significant changes in restorative treatment decisions based on VIM and VIF when compared to VI. The reproducibility between the methods was good for VI vs. VIM (kappa = 0.64) and moderate for VI vs. VIF (kappa = 0.56). In contrast, the inter-examiner reproducibilities expressed as Kappa were considerably lower for VIM (kappa = 0.46 +/- 0.17) and VIF (K = 0.42 +/- 0.19). It was concluded that the inter-examiner reproducibility can be improved with a calibration process based on a simple feedback method and that inter-examiner variation, especially without calibration, may be as important a factor for restorative treatment decisions as the diagnostic method itself.

Chi-Square Distribution↗

PubMed1997

Self-assessed bleeding and plaque as methods for improving gingival health in adolescents.

The aim of this longitudinal study was to compare the effectiveness, in terms of cognitive and clinical changes, of two oral self-care promoting interventions based on a self-assessment of bleeding from gums or of presence of plaque. Adolescent students (age 14.0 + 0.7 years) from two health districts in Helsinki, Finland, participated in this one-year study. The self-assessment of bleeding group (n = 172) recorded bleeding during tooth brushing and inter-proximal cleaning with toothpicks on a single session. The self-assessment of plaque group (n = 156) recorded the presence of plaque with disclosing dye. Both programmes resulted in comparable clinical improvement in bleeding on probing over 9 months. Increased awareness of gingivitis was associated with clinical improvement. The subjects' socio-economic background, baseline gingival health status and age were statistically significantly associated with gingival health improvement during the follow-up. The results support earlier reports on self-assessment and suggest that both self-assessment approaches are beneficial for promoting gingival health in adolescents.

Adolescent↗

PubMed1997

Determinants of self-assessed gingival health among adolescents.

The purpose of the present cross-sectional study was to assess the extent of agreement between clinical and self-assessed gingival health and to investigate possible factors associated with the amount of self-assessed gingival bleeding. A study group comprising students enrolled in grade 7 or 8 in Helsinki, Finland (n = 172), performed a self-assessment based on two tests: the amount of bleeding after toothbrushing and after interproximal tooth cleaning with toothpicks. Clinical examinations based on bleeding on probing (BOP%) were carried out by four local community dentists. The highest observed kappa value was 0.43 for the agreement between BOP% and self-assessment when tested with different cut-off points of diagnosis. Multivariate analysis showed that clinical status and toothbrushing frequency were statistically significantly associated with self-assessed gingival bleeding in both tests. Socioeconomic status and locus of control orientation were also statistically significant factors in the toothpick test. In conclusion, the validity of self-assessment of bleeding was sufficient for monitoring adolescents' gingival health in groups. Self-assessed bleeding was explained by the same factors that were associated with clinical gingival health status.

Adolescent↗

PubMed1996

Self-assessed bleeding in monitoring gingival health among adolescents.

The purpose of this descriptive, cross-sectional community-based investigation was to assess the self-assessment of bleeding and plaque as methods to monitor gingival health among adolescents. Two study groups (n = 184 each) of 14-year-old Finnish school children performed either of self-assessment plaque or bleeding. Prior to that they were clinically examined by 10 dentists from the community dental service who recorded bleeding on probing from four surfaces of all teeth (BOP%) and Community Periodontal Index of Treatment Needs (CPITN) status. The self-assessment of plaque was not significantly correlated with a clinical bleeding on probing measurement (BOP%). The self-assessment of bleeding, based on observed bleeding after toothbrushing and after interproximal cleaning with toothpicks, exhibited statistically significant correlation with BOP% (r = 0.54, P < 0.001). Percent agreement was 75%, kappa agreement 0.33, sensitivity 31% and specificity 71%, respectively. In conclusion, the preliminary results suggest that the self-assessment of bleeding does not have sufficient validity for screening individuals but it could be a useful method for monitoring gingival health of populations, in particular, if the concurrent aim is to enhance periodontal awareness.

Adolescent↗

PubMed1995

Smoking and oral health: a population survey in Finland.

OBJECTIVES: A survey was conducted to study smokers' oral health behaviors and attitudes, and to determine if smokers were advised by their dentists to quit smoking. METHODS: A random sample of 1,200 adults 15 to 64 years of age living in the province of North Karelia, Finland, was selected in each of two study years (1990 and 1991) and surveyed using a mail questionnaire. The 102-item questionnaire solicited information on smoking status, oral health behaviors, missing teeth, perceptions of tobacco's harmful effects on oral health, smoking status and quitting, and advice on smoking cessation provided by dentists. Variations in behaviors and opinions according to smoking status were analyzed. RESULTS: Nonsmokers reported more frequent healthy oral health behaviors than did daily smokers, with the exception that no difference in toothbrushing frequencies existed among women. Daily smoking was associated with increased use of sugar in tea or coffee, and with more frequent alcohol consumption. Daily smoking was correlated with the number of missing teeth in bivariate analyses, but not in multivariate analyses. Fewer daily smokers than nonsmokers considered smoking to have harmful effects on oral health. The majority of daily smokers, however, wanted to quit. Eight percent of daily smokers reported that they had been advised by their dentist to quit. CONCLUSIONS: Dentists need to provide patients with counseling on tobacco use because of the desire of many smokers to quit. Counseling of smokers by the oral health team requires special attention and skills, because smokers' health behaviors and attitudes appear to be less favorable to oral health compared to nonsmokers.

Adolescent↗

PubMed1995

Modified distal metatarsal osteotomy for hallux valgus.

Sixty-three feet in 44 patients with a hallux valgus, which had been operated on using a modified distal osteotomy were reviewed after a mean follow-up of 4.6 years. A modification of Mitchell's and Mommsen's osteotomies was used without any fixation material. The mean correction of the intermetatarsal angle was 2.6 degrees and of the hallux valgus angle 5.2 degrees. Good subjective result was achieved in 90% of the feet. In six (9.5%) cases the hallux valgus angle was worse after the operation. The method used seems to be too unreliable to be continued. Patient selection was found to be of great importance. Hallux valgus angle of more than 40 degrees was less suitable for this kind of operation.

Adult↗

PubMed1994

Self-reported gingivitis and bleeding gums among adolescents in Helsinki.

The purpose of this descriptive cross-sectional community based investigation was to analyze the relationship between professionally measured and perceived gingival health in a sample of 1217 adolescents (age 14.0 +/- 0.7 yr). The responses to two questionnaire items relating to self-reporting of "gingivitis" ("inflammation of gums" in Finnish) and "bleeding from gums" are reported along with Community Periodontal Index of Treatment Needs (CPITN), percentage of bleeding sites (BOP%) and modified Papillary Bleeding Index (PBI) scores. It was found that current or past "gingivitis" was less often reported than "bleeding from gums" by this sample and that responses to both items exhibited low levels of agreement with the clinical measures. The results suggest that the self-reporting of gingival health may be useful in monitoring the gingival health of populations but does not have sufficient validity for screening individuals for gingivitis as defined by dental professionals. Furthermore, it is suggested that the term "bleeding from gums" rather than "gingivitis" should be used during clinical or group oral health promotion.

Adolescent↗