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Biomedical subjects

R Luukkainen

Publications and source records attributed to R Luukkainen.

At least 55 records · Page 3Linked to original sources

Persistence of parvovirus B19 in synovial fluid and bone marrow.

OBJECTIVES: To determine whether parvovirus B19 (B19) persists in rheumatoid arthritis (RA). METHODS: Polymerase chain reaction (PCR) was used to detect parvovirus B19 genome in the synovial fluid cells or peripheral blood mononuclear cells from 61 patients with early RA; bone marrow from one patient was also studied. The synovium or synovial fluid cells from 28 patients with advanced RA, and synovial fluid cell samples from 18 patients with reactive arthritis (as controls) were studied. Two separate sets of primers and probe were used. RESULTS: Parvovirus B19 specific gene sequences were detected in two patients with early arthritis fulfilling the criteria for RA. CONCLUSION: Parvovirus B19 does not play a significant role in the aetiopathogenesis of RA. However, a few cases of a disease indistinguishable from RA may be triggered by parvovirus B19 infection.

Adult↗

Relationship of rheumatoid factor to lung diffusion capacity in smoking and non-smoking patients with rheumatoid arthritis.

We studied the relationship of serum rheumatoid factor (RF) and certain other variables to lung diffusion capacity for carbon monoxide (DLCO) in patients with rheumatoid arthritis (RA). In non-smoking patients none of the examined variables correlated significantly to DLCO whereas in smokers RF showed a significant (p < 0.01) negative correlation in this respect. These results indicate that smoking in connection with RF may contribute to reduced DLCO in RA patients.

Adult↗

Isolation and identification of 12 microcystins from four strains and two bloom samples of Microcystis spp.: structure of a new hepatotoxin.

Sixteen microcystins, cyclic heptapeptide hepatotoxins, were isolated and purified by high performance liquid chromatography (HPLC) and thin layer chromatography (TLC) from four hepatotoxic strains and two Microcystis spp. bloom samples originating from five different lakes in Finland. The structures of a new [Dha7]MCYST-FR and 11 known microcystins MCYST-LR, [D-Asp3]MCYST-LR, [Dha7]MCYST-LR, [D-Asp3, Dha7] MCYST-LR, MCYST-RR, [D-Asp3]MCYST-RR, [Dha7]MCYST-RR, [D-Asp3,Dha7]MCYST-RR, [L-Ser7]MCYST-RR, MCYST-YR and [Dha7] MCYST-YR were assigned based on amino acid analysis, fast atom bombardment mass spectrometry (FABMS) and tandem FABMS. Four other new compounds allowed only determination of their molecular formulas and amino acid components because of inadequate amounts obtained. [Dha7]MCYST-RR was found most frequently in these samples as the main toxin.

Bacterial Toxins↗

Intestinal flora in early rheumatoid arthritis.

To study the role of intestinal flora in the pathogenesis of RA, we have applied computerized gas-liquid chromatography (GLC) for bacterial cellular fatty acids (CFAs) present in the stool. The CFA spectra represents the total composition of bacterial CFAs in a faecal sample. Correlation and cluster analysis of CFA spectra gathers samples with quantitatively and qualitatively similar bacterial flora into clusters, which then reveal the relationship of samples to each other. Stool samples were collected at the time of hospital admission from patients with early RA before any specific treatment. The CFA spectra in stool samples of RA patients were significantly different from those of non-RA controls. Patients with erosive RA formed a group most clearly different from the controls. Analyses based on the CFA composition of reference bacteria revealed that anaerobic bacteria are primarily responsible for the differences observed. These results suggest that intestinal bacteria play a role in the development of RA.

Arthritis, Rheumatoid↗

Does parvovirus B19 have a role in rheumatoid arthritis?

OBJECTIVES: To determine whether parvovirus B19 (B19) infection is associated with rheumatoid arthritis (RA). METHODS: The polymerase chain reaction was applied to serum, cells isolated from synovial fluid, and synovial fluid. Enzyme immunoassay technique was used to detect antibodies against B19. RESULTS: Of 142 patients with early RA (onset of disease under one year) and 67 control patients, serological evidence of recent parvoviral infection was found in 4/135 and 2/62, respectively. However, no evidence for the presence of parvoviral DNA was observed in 18 synovial fluids, 21 samples of synovial fluid granulocytes or 40 sera, all obtained from 65 patients diagnosed with early RA. CONCLUSION: Although there is published evidence of chronic rheumatoid-like arthropathy following acute parvovirus infection, our findings do not support the involvement of B19 in the aetiopathogenesis of RA.

Adult↗

No evidence of adenoviral hexon regions in rheumatoid synovial cells and tissue.

OBJECTIVE: To investigate whether adenoviral DNA is present in synovial specimens from patients with rheumatoid arthritis (RA). METHODS: Synovial fluid (SF) cells from 53 patients with early RA (duration less than 1 year) and synovial tissue samples of 20 patients with advanced RA were studied by using polymerase chain reaction for the presence of adenoviral DNA. The controls were 21 patients with other arthropathies. RESULTS: No adenoviral DNA was found in the SF leukocytes or synovial tissue of any of the patients with arthritis. CONCLUSION: These findings do not indicate that adenoviruses play a role in the etiology of RA. However, they do not exclude adenoviruses as an occasional cause of persistent or recurrent inflammatory arthritis.

Adenoviruses, Human↗

Prognostic significance of synovial fluid analysis in estimating the efficacy of intra-articular corticosteroid injection in patients with spondylarthropathy.

The predictive value of synovial fluid (SF) analysis and some other variables for the efficacy of intra-articular corticosteroid therapy of knee joints in 20 patients with spondylarthropathy and hydropsy in a knee joint was estimated in a prospective study. The knee joints were initially aspirated and 30 mg triamcinolone hexacetonide injected intra-articularly. The tenderness scores and the circumferences of the knee joints were measured at the start and after the two months follow up period. Between the patients with and without improvement in tenderness scores of the knee joints SF protein (p = 0.021), SF lactate (p = 0.033), SF IgG (p = 0.018) and SF IgM (p = 0.047) differed significantly, all being lower in patients with improved tenderness scores. There were no significant differences in the variables between patients with at least 2 centimetres decrease of knee joint difference and those with less during follow up.

Adrenal Cortex Hormones↗

Long-term antiepileptic efficacy of vigabatrin in drug-refractory epilepsy in mentally retarded patients. A 5-year follow-up study.

The long-term clinical, neurophysiologic, and psychological effects of add-on vigabatrin treatment were evaluated in a group of 36 mentally handicapped patients with drug-refractory epilepsy. After an initial 3-month follow-up period, 15 (42%) of 36 patients had at least a 50% decrease in seizure frequency compared with baseline. After a 2-year follow-up period, nine (25%) of 36 patients retained the initially observed antiepileptic effects of vigabatrin, and after 5 years, eight (22%) of 36 patients did so. Five (33%) of the 15 patients who initially exhibited a favorable antiepileptic response to vigabatrin lost that response during a 5-year follow-up. Partial-onset seizures represented the seizure type best controlled by vigabatrin. Side effects were mostly mild, and plasma levels of other antiepileptic medication remained unchanged. No impairment of psychological performance was observed during vigabatrin treatment compared with baseline. Also, no clear change was observed in the background or epileptiform activity in the electroencephalogram during the study. Our findings suggest that vigabatrin as an add-on therapeutic effectively controls seizures in a subpopulation of patients with severe epilepsy. In addition, the antiepileptic response, if achieved, is long lasting in about half of the patients.

Adult↗

Detection of herpesviruses by polymerase chain reaction in lymphocytes from patients with rheumatoid arthritis.

OBJECTIVE: To investigate the occurrence of herpesviruses, including Epstein-Barr virus (EBV), herpes simplex viruses types 1 and 2 (HSV-1; HSV-2), and human herpesvirus 6 (HHV-6), in lymphocytes from patients with rheumatoid arthritis (RA) of less than 1 year's duration. METHODS: The polymerase chain reaction was applied to cells isolated from synovial fluid and peripheral blood. Indirect immunofluorescence and enzyme immunoassay techniques were used to detect antibodies against EBV and HSV, respectively. RESULTS: EBV DNA was present in synovial fluid lymphocytes from 19% (7 of 37) of the RA patients and 33% (5 of 15) of the patients with reactive arthritis (ReA). Peripheral blood lymphocytes harbored EBV DNA in 39% of the RA patients, 39% of the ReA patients, 27% of the patients with other arthropathies, and in 31% of the healthy control subjects. HSV-1, HSV-2, and HHV-6 viral DNA was not detected in cells from the synovial fluid or peripheral blood. CONCLUSION: Our findings do not support the participation of EBV, HSV-1, HSV-2, or HHV-6 in the pathogenesis of RA. A role for the highly prevalent EBV cannot be excluded, however, since potential contributions may become manifest only when other necessary factors are involved. RA pathogenesis caused by an overproduction of the EBV virus is nevertheless highly unlikely.

Adult↗

Isolation and identification of eight microcystins from thirteen Oscillatoria agardhii strains and structure of a new microcystin.

Microcystins (cyclic heptapeptide hepatotoxins), isolated from 13 freshwater Oscillatoria agardhii strains from eight different Finnish lakes by high-performance liquid chromatography, were characterized by amino acid analysis, fast atom bombardment mass spectrometry (FABMS), and tandem FABMS (FABMS/collisionary-induced dissociation/MS). All strains produced two to five different microcystins. In total, eight different compounds, of which five were known microcystins, were isolated. The known compounds identified were [D-Asp3]MCYST (microcystin)-LR, [Dha7]MCYST-LR, [D-Asp3]MCYST-RR, [Dha7]MCYST-RR, and [D-Asp3,Dha7]MCYST-RR. This is the first time that isolation of these toxins from Oscillatoria spp., with the exception of [D-Asp3]MCYST-RR, has been reported. Three of the strains produced a new microcystin, and the structure was assigned as [D-Asp3,Mser7]MCYST-RR. The structures of two new microcystins, produced as minor components by one Oscillatoria strain, could not be determined because of the small amounts isolated from the cells. Four strains produced [Dha7]MCYST-RR as the main toxin, but [D-Asp3]MCYST-RR was clearly the most abundant and most frequently occurring toxin among these isolates of O. agardhii.

Amino Acid Sequence↗

Detection of cytomegalovirus DNA in cells from synovial fluid and peripheral blood of patients with early rheumatoid arthritis.

OBJECTIVE: To study the role of cytomegalovirus (CMV) in the etiology of rheumatoid arthritis (RA). METHODS: Polymerase chain reaction (PCR), immunoperoxidase staining for CMV specific antigens, virus isolation and antibody assays were applied to study samples from patients with RA of less than one year's duration. RESULTS: By PCR, CMV DNA was detected in granulocytes from 3 of 24 synovial fluid (SF) samples and in 10 of 43 peripheral blood samples of patients with RA. These figures are not significantly different from those observed for the control groups (reactive arthritis, other arthropathies, healthy individuals). By immunoperoxidase staining, no evidence for the CMV antigens was observed in the SF cells. All the virus isolations were negative, and the level of CMV specific circulating antibodies in RA was not different from that in the other groups. CONCLUSION: In spite of the negative results, the potential role of CMV in the etiology of RA cannot be totally excluded on the basis of these results; the mutual contribution of the triggering agent and the host response in genetically susceptible individuals is discussed.

Adult↗

Predictive value of synovial fluid analysis in rheumatoid arthritis. A 7.5-year follow-up study.

OBJECTIVES: To evaluate the prognostic value of some synovial fluid variables in patients with rheumatoid arthritis. METHODS: Twenty-nine patients with erosive rheumatoid arthritis and hydropsy in a knee joint were followed for 7.5 years in a prospective study. At the start of the study the knee joints were aspirated and 15 synovial fluid variables were analyzed. The patients were divided into two groups according to whether or not there had been progress of radiologically detected destruction in the knee joints during the follow-up. RESULTS: Of the synovial fluid variables at the start, only C3 (p = 0.030) and acid phosphatase (p = 0.047) differed significantly between the groups, the former being lower and the latter higher in patients with deterioration of knee joints. CONCLUSIONS: These preliminary results may indicate that low synovial fluid C3 and high acid phosphatase predict poor prognosis in a joint affected by rheumatoid arthritis.

Acid Phosphatase↗

How often is seropositive rheumatoid arthritis an erosive disease? A 17-year followup study.

OBJECTIVE: The frequency of erosiveness was studied in rheumatoid arthritis (RA) by longterm followup. METHODS: A community based cohort of 263 patients with recent onset (< or = 6 months) arthritis were followed in Heinola. At 8-year followup examination 113 cases were found to have rheumatoid factor positive (seropositive) nonspecific arthritis, and 15 were nonerosive in the radiographs. The 15 patients were reexamined in 1992 (17-year followup). RESULTS: Eleven of 15 were found to have erosive disease, and of these, 6 had putative psoriatic arthritis, 4 RA, and one monoarthritis of the knee. Of the remaining 4 seropositive nonerosive cases only one fulfilled the 1987 American College of Rheumatology (ARA) criteria for RA. CONCLUSION: In patients with seropositive RA with 4 1987 ARA criteria, 99% developed erosive disease.

Adolescent↗

Yersinia enterocolitica activates a T helper type 1-like T cell subset in reactive arthritis.

The profile of lymphokines secreted by 14 T cell clones and 24 T cell lines reactive with Yersinia Ag isolated from the synovial fluid cells of two HLA-B27+ patients with Yersinia-triggered reactive arthritis was characterized. In response to Ag-specific or -nonspecific stimulation, all of the Yersinia-reactive T cell clones and lines had a pattern of lymphokine secretion resembling that of murine (Th1) cells. A total of 50% of T cell lines and clones randomly isolated from a reactive arthritis patient, without prior in vitro stimulation with Yersinia Ag, also exhibited a Th1-like profile of cytokine secretion upon nonspecific activation. This indicates that the selective expansion of this subset of T cells had already occurred in vivo. The possibility that the predominance of Th1-like T cells was an artefact generated by the T cell cloning procedure was excluded; 50% of the randomly isolated T cell clones and lines produced IL-4, IL-5, or both cytokines upon nonspecific activation. These results indicate that Yersinia Ag selectively activate a Th1-like subset of T cells in patients with Yersinia-triggered reactive arthritis. Accumulation of such cells in the synovial tissue of patients with reactive arthritis may play a key role in the pathogenesis of this disease.

Antigens, Bacterial↗

Two new L-serine variants of microcystins-LR and -RR from Anabaena sp. strains 202 A1 and 202 A2.

Two new microcystins, [L-Ser7]microcystin-LR (1) and [L-Ser7]microcystin-RR (2), were isolated from a filamentous fresh water cyanobacterium (blue-green alga), Anabaena sp. strain 202 A1, along with the two major toxins, [Dha7]microcystin-LR (3) and [Dha7]microcystin-RR (4) and their minor components the D-Asp variants [D-Asp3,Dha7]microcystin-LR (5) and [D-Asp3,Dha7]microcystin-RR (6). Anabaena sp. strain 202 A1 also produced another new toxin, whose structure is tentatively proposed as [D-Asp3,L-Ser7]microcystin-XR (7), where X is a leucine homologue. Anabaena sp. strain 202 A2 produced one new microcystin, 1, and three known microcystins, 3, 4, and 5. The structures of the toxins were assigned based on their amino acid analyses, and fast atom bombardment mass spectrometry data.

Amino Acid Sequence↗

Isolation and characterization of a variety of microcystins from seven strains of the cyanobacterial genus Anabaena.

Hepatotoxins (microcystins) from seven freshwater Anabaena strains originating from three different Finnish lakes and one lake in Norway were isolated by high-performance liquid chromatography and characterized by amino acid analysis and fast atom bombardment mass spectrometry. All strains produced three to seven different microcystins. A total of 17 different compounds were isolated, of which 8 were known microcystins. The known compounds identified from six strains were MCYST (microcystin)-LR, [D-Asp3]MCYST-LR, [Dha7]MCYST-LR, [D-Asp3,Dha7]MCYST-LR, MCYST-RR, [D-Asp3]MCYST-RR, [Dha7]MCYST-RR, and [D-Asp3,Dha7]MCYST-RR. With the exception of MCYST-LR and [D-Asp3]MCYST-LR, this is the first time that isolation of these toxins from Anabaena strains has been reported. Three of the strains produced one to three toxins as minor components which could not be identified. Anabaena sp. strain 66 produced four unidentified toxins. The other Anabaena strains always contained both MCYST-LR and MCYST-RR and/or their demethyl variants. Quantitative differences between toxins within and between strains were detected; at times MCYST-LR and at other times MCYST-RR or demethyl derivatives thereof were the most abundant toxins found in a strain.

Amino Acid Sequence↗