Application of markers of collagen metabolism in serum and synovial fluid for assessment of disease process in patients with rheumatoid arthritis.

OBJECTIVE--To assess the potential of markers of collagen metabolism to reflect disease processes in rheumatoid arthritis (RA). METHODS--Serum (S) and synovial fluid (SF) from 59 patients with RA, and a knee joint effusion and serum from 90 control subjects were studied with radioimmunoassays for the aminoterminal propeptides of type I and type III procollagens (PINP and PIIINP, respectively). The breakdown of type I collagen was quantified with a radioimmunoassay for the cross linked carboxyterminal telopeptide of type I collagen (ICTP). RESULTS--About 50% of the patients had increased S-ICTP and S-PIIINP values, whereas S-PINP was increased in only 20% of the patients. The mean SF:S ratios of these markers varied between 4 (for ICTP) and 340 (for PIIINP), indicating that markers of collagen metabolism are formed locally and then released into the circulation. SF-PINP and SF-PIIINP correlated with each other (rs = 0.86, p < 0.001) and with SF-ICTP (rs = 0.69, p < 0.001, and rs = 0.65, p < 0.001, respectively). SF-ICTP was clearly related to radiographic findings in the corresponding knee joint, patients with gross bone deformation having the greatest SF-ICTP concentrations. S-ICTP and S-PIIINP also correlated with conventional markers of disease activity, such as C reactive protein and joint swelling score. CONCLUSION--Markers of collagen metabolism both in serum and synovial fluid can be measured to provide an assessment of disease process in patients with RA. ICTP and PIIINP are the most informative.     

The human brain processes visual changes that are not cued by attended auditory stimulation

Event-related potentials (ERPs) to visual stimuli were recorded from the scalp of eight adult humans performing a task in which they counted vowels from a heard story. In the oddball condition, a repeated (standard) light bar of 50 ms in duration was rarely (P = 0.1) replaced by a (deviant) one differing in orientation from the standard. In the control condition, standards were simply omitted from the series and only (alone-) deviants retained. In both conditions, visual stimuli were asynchronous with auditory-task-relevant stimuli. ERPs to deviants significantly differed in amplitude from those to standards in the midline electrodes centrally, parietally and occipitally at 160-200 ms from stimulus onset. Occipitally, such a difference was absent between ERPs to alone-deviants and those to standards. The occipital differential ERPs to deviants, which thus could be found only when standards were present in the series, are discussed in the context of the mismatch negativity (MMN).     

Molecular and biological analysis of echovirus 9 strain isolated from a diabetic child

The full-length infectious cDNA clone was constructed and sequenced from the strain DM of echovirus 9, which was recently isolated from a 6-week-old child at the clinical onset of type 1 diabetes. Parallel with the isolate DM, the full-length infectious cDNA clone of the prototype strain echovirus 9 Barty (Barty-INF), was constructed and sequenced. Genetic relationships of the sequenced echo 9 viruses to the other members of the human enterovirus type B species were studied by phylogenetic analyses. Comparison of capsid protein sequences showed that the isolate DM was closely related to both prototype strains: Hill and Barty-INF. The only exception was the inner capsid protein VP4 where serotype specificity was not evident and the isolate DM clustered with the strain Hill and the strain Barty-INF with echovirus 30 Bastianni. Likewise, the nonstructural protein coding region, P2P3, of isolate DM was more similar to strain Hill than to strain Barty-INF. However, like echovirus 9 Barty, the isolate DM contained the RGD-motif in the carboxy terminus of capsid protein VP1. By blocking experiments using an RGD-containing peptide and a polyclonal rabbit antiserum to the alpha(v)beta(3)-integrin, it was shown that this molecule works as a cellular receptor for isolate DM. By using primary human islets, it was shown that the isolate DM is capable of infecting insulin-producing beta-cells like the corresponding prototype strains did. However, only isolate DM was clearly cytolytic for beta-cells. The infectious clones that were made allow further investigations of the molecular features responsible for the diabetogenicity of the isolate DM.     

Phylogenetic analysis of rhinovirus isolates collected during successive epidemic seasons

Human rhinoviruses (HRV) have been shown to be the major causative agent for mild respiratory infections, but also associated with more serious diseases, such as acute otitis media and pneumonia in children, and asthma. Despite the economical and medical importance of HRV, little is known about the circulation and genetic diversity of HRV during a given season. The aim of this study was to genetically characterize HRV strains causing acute respiratory infections in a cohort of small children during a 2 years follow-up time. Genetic relationships between 61 HRV field isolates were studied using partial genomic sequencing in the VP4/VP2 region (420 nt) and phylogenetic analysis of these sequences. Sequences from the clinical isolates clustered in the two previously known phylogenetic clades, the designated genetic group 2 (including HRV 14) being more predominant. The maximum genetic variation within group 1 was 32.3% and within group 2 it was 32.7%. Several distinct clusters could be observed, some of which were strictly seasonal, whereas some other variants were detected during several seasons. The results of this study show striking genetic diversity of the HRV strains circulating in a given community during a short time.     

HLA haplotype analysis in Finnish patients with rheumatoid arthritis

OBJECTIVE: To further characterize the HLA gene products that play an important role in the pathogenesis of rheumatoid arthritis (RA). METHODS: One hundred thirty-four haplotypes from 67 Finnish RA patients and 77 control haplotypes were analyzed for HLA-DRB1 loci, associated alleles of the HLA-DQB1 locus, alleles of the type 2 transporter-associated antigen processing (TAP2) genes, and HLA-B27. In addition, a panel of microsatellite markers within the HLA class I and class III regions was studied. RESULTS: The frequency of HLA-DRB1*04 in the haplotypes of RA patients was found to be 34% (45 of 134) compared with 14% (10 of 72) in control haplotypes (P = 0.004). The frequency of HLA-DRB1*13 was decreased in RA haplotypes (4%, or 5 of 134) in contrast to control haplotypes (24%, or 17 of 72) (P = 0.000031). The decrease in DRB1*13 was not secondary to the increase in DRB1*04, since it was also found among DRB1*04-negative haplotypes (P < 0.001). The DRB1*13-associated DQB1*0604 allele was similarly decreased in RA haplotypes (P = 0.025). The TAP2I allele of I/J dimorphism was increased in RA patients (85%, or 114 of 134) as compared with controls (69%, or 49 of 71) (P = 0.011). Of the tumor necrosis factor (TNF) microsatellite alleles, TNFa6 and TNFb5 were found to be increased in RA haplotypes (for a6 27% versus 5% in controls [P = 0.00043], and for b5 43% versus 26% in controls [P = 0.037]). CONCLUSION: Both protection-associated and susceptibility-associated alleles can be found among HLA class II genes, and the results suggest that loci outside DR/DQ may contribute to the pathogenesis of RA.     

Mononuclear cell response to enterobacteria and Gram-positive cell walls of normal intestinal microbiota in early rheumatoid arthritis and other inflammatory arthritides

OBJECTIVE: To study whether enterobacteria and Gram-positive bacterial cell walls (BCW) derivedfrom normal intestinal microbiota are involved in the etiopathogenesis of early rheumatoid arthritis (RA). METHODS: Peripheral blood mononuclear cells (PBMC) and synovial fluid mononuclear cells (SFMC) were isolatedfrom patients with early RA (the average duration of 5 months) and the controls (other types of inflammatory arthritis). The mononuclear cell proliferation and tumor necrosis factor-alpha (TNF-alpha) responses to heat-killed Salmonella enteritidis (SE). Yersinia enterocolitica (YE), and Escherichia coli (EC), and to Gram-positive BCW derived from four common intestinal indigenous bacteria, Eubacterium aerofaciens (EA), Eubacterium limosum (EL), Lactobacillus casei (LC), and Lactobacillus fermentum (LF), and a BCW derived from a pathogen, Streptococcus pyogenes (SP) were investigated. RESULTS: 39% or 56% of patients with early RA showed significant proliferation responses by PBMC or SFMC against enterobacteria, respectively. In other types of arthritis, corresponding figures were 59% or 66%. When BCW were used as antigens, 8.1% or 23% of patients with early RA showed proliferation responses by PBMC or SFMC, respectively. In other types of arthritis the corresponding figures were 7.5% or 35%, respectively. However, TNF-alpha production by SFMC stimulated by EA BCW, SE, YE or EC, was significantly higher in early RA than in other types of arthritis. CONCLUSION: These results suggest that SFMC reacting with enterobacteria or BCW exist in some patients with early RA, but also in other types of inflammatory arthritis. Intestinal bacterial agents may play a role in the etiopathogenesis of RA, but the effect appears to be non-specific.     

Marrow versus peripheral blood for geno-identical allogeneic stem cell transplantation in acute myelocytic leukemia: influence of dose and stem cell source shows better outcome with rich marrow

Several studies have compared bone marrow (BM) and peripheral blood (PB) as stem cell sources in patients receiving allografts, but the cell doses infused have not been considered, especially for BM. Using the ALWP/EBMT registry, we retrospectively studied 881 adult patients with acute myelocytic leukemia (AML), who received a non-T-depleted allogeneic BM (n = 515) or mobilized PB (n = 366) standard transplant, in first remission (CR1), from an HLA-identical sibling, over a 5-year period from January 1994. The BM cell dose ranged from 0.17 to 29 x 10(8)/kg with a median of 2.7 x 10(8)/kg. The PB cell dose ranged from 0.02 to 77 x 10(8)/kg with a median of 9.3 x 10(8)/kg. The median dose for patients receiving BM (2.7 x 10(8)/kg) gave the greatest discrimination. In multivariate analyses, high-dose BM compared to PB was associated with lower transplant-related mortality (RR = 0.61; 95% CI, 0.39-0.98; P =.04), better leukemia-free survival (RR = 0.65; 95% CI, 0.46-0.91; P =.013), and better overall survival (RR = 0.64; 95% CI, 0.44-0.92; P =.016). The present study in patients with AML receiving allografts in first remission indicates a better outcome with BM as compared to PB, when the dose of BM infused is rich.