Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Pekka Vilja is active.

Publication


Featured researches published by Pekka Vilja.


International Journal of Radiation Oncology Biology Physics | 1994

Sucralfate mouth washing in the prevention of radiation-induced mucositis: A placebo-controlled double-blind randomized study

Tuula A. Makkonen; Pia Boström; Pekka Vilja; Heikki Joensuu

PURPOSE To evaluate the value of sucralfate mouth washings in prevention of radiation-induced mucositis. METHODS AND MATERIALS Forty patients with head and neck cancer were randomized to use either sucralfate mouth washing 1 g six times daily during irradiation (n = 20) or to placebo washing (n = 20). Mouth washing was started at the beginning of radiation therapy and continued to the end of the therapy (7-10 weeks). Assessment of the degree of radiation mucositis and collection of stimulated saliva samples were done weekly during the therapy. Salivary lactoferrin and albumin, suggested markers for the degree of mucositis, were analyzed from stimulated whole saliva samples. RESULTS All patients developed radiation-induced mucositis of varying degree after irradiation of about 30 Gy. No difference in the visually assessed degree of mucositis or oral pain reported by the patients was found between the study and the control groups. However, the patients treated with sucralfate used less anesthetic mouth washing and their salivary lactoferrin and albumin levels were lower. CONCLUSION Although the trial produced no direct clinical evidence indicating that sucralfate mouth rinses prevent radiation-induced mucositis, the decrease in the salivary lactoferrin and albumin levels suggests that sucralfate has a slight protective effect on the oral mucosa.


Journal of Immunological Methods | 1985

A rapid and sensitive non-competitive avidin-biotin assay for lactoferrin.

Pekka Vilja; Kai Krohn; Pentti Tuohimaa

We have developed an avidin-biotin assay for the detection of lactoferrin in human seminal plasma. We compared 5 modifications of this assay, and found the non-competitive avidin-biotin assay (NABA) to be the most sensitive. The detection limit of 3-step NABA was 0.2 or 0.1 ng lactoferrin/ml, depending whether avidin-biotin-peroxidase complex (ABC) or avidin-peroxidase was used. The intra-assay and inter-assay coefficients of variation for 3-step NABA were 6.2 and 8.5%, respectively. The lactoferrin levels of human seminal plasma samples measured by 3-step NABA and radioimmunoassay (RIA) showed good correlation (r = 0.96). The total performance time of 3-step NABA is flexible and the method can be modified for rapid (less than 1 h) or overnight assay according to need.


International Journal of Radiation Oncology Biology Physics | 1999

Granulocyte macrophage-colony stimulating factor (GM-CSF) and sucralfate in prevention of radiation-induced mucositis: a prospective randomized study

Tuula A. Makkonen; Heikki Minn; Antti Jekunen; Pekka Vilja; Juhani Tuominen; Heikki Joensuu

PURPOSE To compare subcutaneously given molgramostim (GM-CSF) and sucralfate mouth washings to sucralfate mouth washings in prevention of radiation-induced mucositis. METHODS AND MATERIALS Forty head and neck cancer patients were randomly assigned to use either GM-CSF and sucralfate (n = 20) or sucralfate alone (n = 20) during radiotherapy. Sucralfate was used as 1.0 g mouth washing 6 times daily after the first 10 Gy of radiotherapy, and 150-300 microg GM-CSF was given subcutaneously. The grade of radiation mucositis and blood cell counts were monitored weekly. Salivary lactoferrin was measured as a surrogate marker for oral mucositis. RESULTS We found no significant difference between the molgramostim and the control groups in the oral mucositis grade, oral pain, use of analgesic drugs, weight loss, or survival. The median maximum neutrophil counts (median, 9.2 x 10(9)/L vs. 5.9 x 10(9)/L, p = 0.0005), eosinophil counts (median, 1.3 x 10(9)/L vs. 0.2 x 10(9)/L, p = 0.0004), and salivary lactoferrin concentrations were higher in patients who received GM-CSF. The most common toxicities in the GM-CSF plus sucralfate group were skin reactions at the GM-CSF injection site (65%), fever (30%), bone pain (25%), and nausea (15%), whereas the toxicity of sucralfate given alone was minimal. CONCLUSION We found no evidence indicating that subcutaneously given GM-CSF reduces the severity of radiation-induced mucositis.


Acta Odontologica Scandinavica | 1988

Antimicrobial systems of human whole saliva in relation to dental caries, cariogenic bacteria, and gingival inflammation in young adults

Erik Gråhn; Jorma Tenovuo; Olli-Pekka Lehtonen; Erkki Eerola; Pekka Vilja

The association of salivary antibody (total IgA, IgG, and IgM and antibodies reactive with Streptococcus mutans) and non-antibody (lysozyme, lactoferrin, salivary peroxidase, myeloperoxidase, hypothiocyanite, thiocyanate) defense factors with oral health (past and present dental caries, gingival bleeding, the number of salivary S. mutans and lactobacilli) were studied in 50 naval recruits. Dental caries was significantly associated with large amounts of S. mutans, lactobacilli, and total salivary immunoglobulins and with low salivary flow rate and buffer capacity. Salivary anti-S. mutans antibodies did not correlate with dental caries or S. mutans levels. Moreover, none of the salivary non-antibody factors alone had any strong relationship to dental caries or S. mutans levels. Gingival inflammation was associated with elevated levels of lysozyme in whole saliva. It is concluded that in adults the associations between single-point measurements of most salivary antimicrobial constituents and the factors describing oral health are weak.


Journal of Dental Research | 1986

Immunoglobulins and innate antimicrobial factors in whole saliva of patients with insulin-dependent diabetes mellitus.

Jorma Tenovuo; O.-P. Lehtonen; J. Vkari; H. Larjava; Pekka Vilja; P. Tuohimaa

We analyzed the flow rate and composition of paraffin-stimulated whole saliva samples from 35 adult diabetic patients and their age- and sex-matched, non-diabetic, clinically healthy controls. All patients had insulin-dependent diabetes (IDDM) with a mean (± S.D.) duration of 14.0 ± 9.1 years. The saliva analysis included the quantitation of total protein, amylase, immunoglobulins (isotypes A, G, and M), and the non-antibody, innate antimicrobial factors (lysozyme, lactoferrin, salivary peroxidase, myeloperoxidase, thiocyanate, and hypothiocyanite). The whole saliva samples from diabetic patients had significantly higher amounts of IgA (p < 0.001) and IgG (p < 0.05) than did the controls. No differences between the study groups were observed in flow rate, protein content, amylase activity, or IgM. The levels of innate defense factors were similar in both study groups except for salivary peroxidase, which was higher (p < 0.02) among diabetics than among controls. Our results indicate that the antimicrobial defense capacity of whole saliva is not impaired in diabetic patients.


Oral Surgery, Oral Medicine, Oral Pathology | 1986

Changes in the protein composition of whole saliva during radiotherapy in patients with oral or pharyngeal cancer

Tuula A. Makkonen; Jorma Tenovuo; Pekka Vilja; Anders Heimdahl

We analyzed the radiation-induced changes in the flow rate and protein composition of stimulated whole saliva in eleven patients treated for malignant conditions of the head and neck. In all patients the radiation field covered all major salivary glands and a large area of the oral mucosa. Paraffin-stimulated whole saliva samples were collected once 2 to 21 days before therapy and then after 20, 40, and 60 gray (Gy) cumulative dose of irradiation. Five patients also provided samples 6 months after the therapy. Hyposalivation or xerostomia occurred in all patients, although the pretreatment secretion rates were already relatively low. Salivary amylase activities decreased with increasing dose of radiation, especially when expressed as the amount of enzyme secreted per minute. Unusually high salivary concentrations of albumin, lactoferrin, lysozyme, salivary peroxidase, myeloperoxidase, and total protein were observed during the therapy, but most values slowly returned to pretreatment levels after cessation of radiation. It is concluded that the observed qualitative changes in whole saliva components are net effects caused by the cancer itself, radiation therapy given, systemic diseases, or medications, as well as mucosal inflammations.


Fertility and Sterility | 1988

Spontaneous luteinizing hormone surge and cleavage of in vitro fertilized embryos

Reijo Punnonen; Ralph Ashorn; Pekka Vilja; Pentti K. Heinonen; Erkki Kujansuu; Pentti Tuohimaa

The importance of monitoring luteinizing hormone (LH) secretion during gonadotropin stimulation remains controversial. In the present study, the authors evaluated the occurrence of spontaneous LH surges in 170 cycles stimulated by clomiphene citrate and human menopausal gonadotropin, and correlated the success rate of embryo cleavage to the time interval between the occurrence of the LH surge peak value and the time of human chorionic gonadotropin (hCG) administration. LH was quantitated from urine by an avidin-biotin enzyme immunoassay. The results indicated that a spontaneous LH surge occurred in 18% of the cycles. The number of oocytes recovered was not affected by the occurrence of a spontaneous LH surge. In 12% of all cases, the spontaneous LH surge occurred less than 12 hours before the administration of hCG, and in these cases embryo cleavage was not reduced. In 6% of all cases, the spontaneous LH surge occurred over 12 hours before hCG administration, and in these cases embryo cleavage was reduced significantly.


Journal of Dental Research | 1998

Longitudinal Analysis of the Association of Human Salivary Antimicrobial Agents with Caries Increment and Cariogenic Micro-organisms: A Two-year Cohort Study

Varpuleena Kirstilä; P. Häkkinen; H. Jentsch; Pekka Vilja; Jorma Tenovuo

Previous studies of the possible associations of salivary antimicrobial agents with dental caries have given controversial results, obviously mainly because almost all studies have been cross-sectional. Our aim was to find out, in a two-year longitudinal follow-up study, the associations among selected salivary non-immune and immune antimicrobial variables, cariogenic bacteria, and caries increment. The study population was comprised of 63 subjects, all of whom had their 13th birthday during the first study year. In addition to a comprehensive dental examination at baseline and after 2 yrs, paraffin-stimulated whole saliva samples were collected in a standardized way at six-month intervals. Saliva samples were analyzed for flow rate, buffer effect, lysozyme, lactoferrin, total peroxidase activity, hypothiocyanite, thiocyanate, agglutination rate, and total and specific anti-S. mutans IgA and IgG, as well as for numbers of total and mutans streptococci, lactobacilli, and total anaerobic bacteria. Cluster analysis and Spearman-Rank correlation coefficients were used to explore possible associations between and among the studied variables. During the two-year period, a statistically significant increase was observed in flow rate, thiocyanate, agglutination rate, anti-S. mutans IgA antibodies, lactobacilli, and total anaerobes, whereas lysozyme, lactoferrin, and total and anti-S.mutans IgG antibodies declined significantly. Based on various analyses, it can be concluded that, at baseline, total IgG and hypothiocyanite had an inverse relationship with subsequent two-year caries increment, anti-S. mutans IgG antibodies increased with caries development, and mutans streptococci and lactobacilli correlated positively with both baseline caries and caries increment. Total anaerobic microflora was consistently more abundant among caries-free individuals. In spite of the above associations, we conclude that none of the single antimicrobial agents as such has sufficiently strong power to have diagnostic significance in vivo with respect to future caries.


The American Journal of Gastroenterology | 2000

Local challenge on oral mucosa with an α-gliadin related synthetic peptide in patients with celiac disease

Hannu Lähteenoja; Markku Mäki; M. Viander; Ismo Räihä; Pekka Vilja; Immo Rantala; Auli Toivanen; Stina Syrjänen

OBJECTIVE:Gluten-derived peptides (e.g., amino-acids 31–49 of α-gliadin) have been shown to cause changes typical of celiac disease in the gut. Gluten-derived peptides have mostly been used in in vitro studies. The easiest access to the gastrointestinal system may be the mouth. In the present study we were interested to see whether a synthetic peptide corresponding to amino-acids 31–49 of α-gliadin could induce inflammatory changes in the oral mucosa after a local challenge in celiac disease patients.METHODS:The challenge was made by injecting the peptide solution at a concentration of 10 μg/ml submucosally into the oral mucosa of 10 celiac disease patients after a gluten-free diet (GFD) and 12 healthy control subjects. B and CD45RO+ T cells, mast cells, CD3+, CD4+, CD8+ lymphocytes, and αβ and γδ T-cell receptor-bearing (TcRαβ, TcRγδ) lymphocytes were counted and HLA DR expression was determined. The expression of CD25 and Ki-67 antigen was also examined.RESULTS:The peptide significantly increased the total number of T cells in the lamina propria of the celiac disease patients. The expression of T-cell activation marker CD25 (IL-2 receptor), but not that of cell proliferation marker Ki-67, was also significantly increased in the lamina propria after peptide challenge. Such a reaction was not observed in the controls. The numbers of CD3+ and CD4+ T cells in the lamina propria were also increased in celiac disease patients after the challenge. The count of TcRγδ+ cells was very small in the oral mucosa in celiac disease and showed no increase when the oral mucosa was challenged with the peptide. The expression of HLA DR staining was enhanced after the submucosal peptide challenge in celiac disease; however, the difference was not statistically significant.CONCLUSIONS:The results show that in the celiac disease patients after the peptide challenge the oral mucosal lamina propria responds with a nonproliferative increase of lymphocytes. Thus, submucosal challenge with the peptide 31–49 can be used as an aid in the diagnosis of celiac disease. However, further studies with optimized methodology, including various concentrations of the peptide, adjuvants, other peptides, etc., are warranted, especially because the oral mucosa provides the easiest access to an in vivo peptide challenge in celiac disease.


Journal of Clinical Immunology | 1994

Salivary Defense Factors and Oral Health in Patients with Common Variable Immunodeficiency

Varpuleena Kirstilä; Jorma Tenovuo; Olli Ruuskanen; Jukka Nikoskelainen; K. Irjala; Pekka Vilja

Studies of oral health in patients with common variable immunodeficiency have given controversial results. Obviously, one major factor modifying the oral health of these patients is saliva, in which the antibody-mediated defense is remarkably impaired compared to that of healthy subjects. However, the occurrence of nonimmunoglobulin (innate) antimicrobial agents in saliva of these patients is virtually unknown. Therefore, we analyzed both immune (total IgA, IgG, IgM, anti-Streptococcus mutans IgA, IgG, and IgM antibodies) and nonimmune (lysozyme, lactoferrin, salivary peroxidase, myeloperoxidase, hypothiocyanite, thiocyanate, and agglutinins) factors in whole saliva of 15 patients with common variable immunodeficiency. All patients were on Ig-replacement therapy (median duration, 10 years; range, 2–25 years), which had normalized their IgG but not their IgA or IgM levels both in serum and in saliva. Also, comprehensive clinical and microbiological analyses were made. The control group comprised 15 age- and sex-matched immunologically healthy subjects. The results showed no notable differences in dental caries, periodontal diseases, or salivary microorganisms but the patients had a history of more frequent oral mucosal lesions and respiratory infections. All innate, nonimmune salivary defense factors were equally abundant in the patients as in the controls, in many cases even at somewhat higher concentrations. These findings suggest that in spite of immunodeficiency, patients with common variable immunodeficiency display normal, perhaps even slightly elevated, levels of nonimmunoglobulin defense factors in whole saliva. This may partly prevent the expected enhanced susceptibility to infectious diseases in the mouths of these patients.

Collaboration


Dive into the Pekka Vilja's collaboration.

Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Kai Krohn

University of Tampere

View shared research outputs
Top Co-Authors

Avatar

Merja Roivainen

National Institute for Health and Welfare

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Researchain Logo
Decentralizing Knowledge