Similarity between chronic reactive arthritis and ankylosing spondylitis.A 32-35-year follow-up study.

OBJECTIVE: We assessed the long-term outcome of recent reactive arthritis (ReA) during 1973-2007 and ankylosing spondylitis (AS) during 1973-1997 to identify similarities in manifestations of disease. METHODS: Radiographs of the sacroiliac, hand and foot joints were taken at onset and at 8, 20, and in ReA 32 years from entry among recent-onset (<6 months) patients; 60 with ReA and 17 with AS. Sacroiliacal joints using the modified New York 1984 criteria and the Larsen score of 0-100 of 20 joints of hands and feet were assessed. The number of swollen joints, patients with orthopaedic operations or iritis or HLA-B27 or retirement because of spondyloarthritis, and ESR were recorded. RESULTS: The onset age of 60 ReA patients (34 men) was 17-54 years, mean 32 (SD 10) and 51 (85%) were HLA-B27 positive. The number of onset swollen joints was 1-5, mean 2.6 (SD 1.6), while in 40 patients at the 30-year check-up it was 0-3, mean 0.2 (SD 0.6). ESR was at onset mean 55 mm/h (SD 33) and at the 30-year check-up 15 mm/h (SD 11). Yersinia enterocolitica type 3 antibodies were raised in 22 (37%) patients at onset. The end-point Larsen score was 2-6, mean 4 in 6 patients. One ankle joint arthroplasty and five smaller operations had been performed. Bilateral grade 2-3 sacroiliitis developed in 9/60 (15%), and unilateral grade 2-4 in 3. The incidence of iritis was 12/60 (20%). Erosive arthritis or iritis or sacroiliitis developed in 24/60 (40%) participants. Thirteen (22%) retired because of arthritis while five died. Of 17 AS patients (8 men), whose age was initially 21-50 years, mean 33 (SD 10), 11 (65%) had rheumatic symptoms years before our first examination. All were HLA-B27 positive and developed grade 2-4 bilateral sacroiliitis during the 20-year follow-up. The end-point Larsen score was 2-22, mean 9 (SD 8) in 5 patients. Hip arthroplasties were performed in one and small-joint operations in 3. ESR was at onset mean 54 mm/h (SD 29), and at the last measurement mean 26 mm/h (SD 21). Iritis was found in 5/17 (29%); seven (41%) retired due to AS; five died. CONCLUSION: Our community-based inception cohorts show that with time, among a number of similarities most often sacroiliitis, peripheral arthritis and iritis developed in both chronic ReA and AS. These HLA-B27-related diseases would appear to be identical. The differences between patients depend on the chronicity of the sickness. The hypothesis that HLA-B27 is related to chronicity of disease seems to be valid.

Cost-effectiveness of infliximab in the treatment of rheumatoid arthritis in clinical practice.

OBJECTIVE: We evaluated the cost-effectiveness of infliximab therapy in Finnish RA patients in a real-life clinical setting and identified factors influencing it, using the national register of biological treatment (ROB-FIN). METHODS: A cost-utility analysis was performed, derived from EQ-5D, and related to HAQ score and disease activity using multiple regression. QALYs were calculated based on these utilities, using patient-level data up to the last control registered. Cost-effectiveness analyses included costs per ACR50 responder, and costs per low DAS28 score (<3.2) achieved, in combination with a clinically significant improvement (>1.2). The costs considered were direct medical costs of infliximab and cost of intravenous infusion. Patient-level costs were calculated based on dose and dosage frequency, and were related to the difference in QALYs resulting from infliximab therapy. RESULTS: The 297 patients had been treated with infliximab for an average of 21 months. The HAQ score and patient's global assessment improved significantly on infliximab therapy. More than two-thirds of the patients achieved a clinically important improvement in HAQ. A QALY gain occurred in 76%. 35% of these had an incremental cost-effectiveness ratio of < or =40,000 Euro/QALY gained, the median cost being 51,884 Euro. The cost per QALY gained was significantly lower for patients achieving an ACR50 response at 3, 12 and 24 months. CONCLUSION: Treatment with infliximab and aiming at ACR50 response appears cost-effective, remembering the restrictions of an observational study set up. Current Care guidelines, which require sufficient disease control when deciding on continuing biological therapy, get support from these findings.

Seronegative oligoarthritis: a 23-year follow-up study.

The aim of the study was to investigate the long-term outcome of non-specific seronegative oligoarthritis in adults. The study included 64 adult patients with recent (<6 months) seronegative oligoarthritis (rheumatoid factor negative, number of swollen joints 1-4 during the first 6 months). Follow-up examinations were carried out at onset and at 1, 3 and 8 years from entry. A total of 47 patients attended the 23-year follow-up. The endpoint outcome was good. Seven had mild erosions in the hands or feet. Only one patient with HLA-B27 developed bilateral sacroiliitis. Three patients had retired from work because of joint disease. The functional outcome of the patients analysed by HAQ was very good after 23 years: 0 in 33 and 0.1-0.9 in 12 of the 47 patients. Reclassification revealed a certain heterogeneity: one case each of rheumatoid arthritis, SLE and ankylosing spondylitis, two cases of post-traumatic arthritis, four of osteoarthrosis, and six of possible reactive arthritis. Out of the remaining 49 patients 15 were HLA-B27 positive and 16 had at least one of the psoriasis-related HLA antigens (HLA-B13, 17, w16). In conclusion, our 23-year prospective follow-up study of patients with seronegative oligoarthritis confirms their favourable outcome. The reason is that the endpoint diagnoses seemed to be similar to those of mild spondylarthropathies.

Characterization of the sec1-1 and sec1-11 mutations.

Sec1 proteins are implicated in positive and negative regulation of SNARE complex formation. To better understand the function of Sec1 proteins we have identified the nature of the temperature-sensitive mutations in sec1-1 and sec1-11. The sec1-1 mutation changes a conserved glycine(443) to glutamic acid. The sec1-11 mutation changes a highly conserved arginine(432) to proline. Based on homology and the crystal structure of the mammalian nSec1p, the corresponding amino acids localize to the 3b domain of nSec1p. Compared to the wild-type Sec1p the mutant proteins are less abundant even at the permissive temperature. Thus, the R432P and G443E mutations may cause structural alterations that affect folding and make the mutant proteins more susceptible to degradation. The remaining part is sufficient for growth and protein secretion at 24 degrees C and thus is likely to be properly folded. At 37 degrees C the mutant proteins become non-functional. In pulse-chase-type experiments the newly synthesized Sec1-1 and Sec1-11 proteins decayed similarly with the wild-type protein. Thus, the non-functionality of the mutant proteins cannot be explained by denaturation-induced degradation only. It is possible that the newly synthesized mutant proteins fold slowly and are susceptible to degradation before they have managed to fold and associate with other proteins. The mutant proteins were unable to interact with the Sec1p-interacting proteins Mso1p and Sso2p in the two-hybrid assay, even at the permissive temperature. These results localize sec1-1 and sec1-11 mutations to a domain of Sec1p and suggest a mechanism by which sec1-1 and sec1-11 cells become temperature-sensitive.

Radiographic remission in seropositive rheumatoid arthritis. A 20-year follow-up study.

OBJECTIVE: Rheumatoid arthritis (RA) is in most instances a progressive disease. Very little information is available on halting of the radiographic damage, particularly in later phases of the disease. We studied radiographic remission of RA lasting to the end of follow-up, covering the period 1973-96. METHODS: Radiographs of hands and feet were taken at onset and at 1, 3, 8, 15 and 20 years from entry in 102 cases of recent onset (< 6 months) seropositive and erosive RA. A Larsen score of 0-100 was formed for 20 joints of hands and feet. If the score did not worsen by more than one point between one of the above time points and the end of the study, the patient was considered to be in remission. RESULTS: Remission was confirmed in 27 (26%) of the patients. In 3 cases the remission was from the 1-year check-up, in 5 from the 3-year check-up, in 6 from the 8-year check-up and in 13 cases from the 15-year check-up. Some of the remission cases had a mild disease from the outset, but there were cases in which the disease process had led to marked joint destruction before slowing down. CONCLUSION: This data may serve as a basis for comparison with subsequent cohort studies on new treatments-of-choice.

Prediction of 20-year outcome at onset of seropositive rheumatoid arthritis.

OBJECTIVE: With the advent of new and expensive antirheumatic treatments with potentially serious side effects, it would be essential to identify as early as possible those rheumatoid arthritis (RA) patients who have a poor prognosis. Here study was made of the prognostic value of different markers recorded at the onset of RA. METHODS: At the 20-year follow-up of our prospective study, 66 patients had rheumatoid factor-positive (RF+) RA. At commencement of follow-up (disease duration < 6 months), the prognostic value of 19 demographic, laboratory, clinical and radiographic variables was tested to explain the 20-year Larsen score for peripheral joints and the Health Assessment Questionnaire (HAQ) index using Somers'd for asymmetrical associations. RESULTS: An association was observed between onset blood platelets (0.17), serum IgG (0.18), the onset Larsen score (0.33) and the 20-year Larsen score. Old age (0.30), serum orosomucoid (0.17), the function score (0.28), morning stiffness (0.28), and grip strength (0.24) were associated with the 20-year HAQ. CONCLUSION: The correlation between the investigated entry variables and end-point outcome was poor. In our discussion we conclude that the most important prognostic factor in RF + RA is the treatment.

Work disability in an inception cohort of patients with seropositive rheumatoid arthritis: a 20 year study.

OBJECTIVE: Information from successive inception cohorts is needed to monitor the long-term prognosis of rheumatoid arthritis (RA) and the effect of treatment on it. We studied work disability and its association with the Health Assessment Questionnaire (HAQ) index and the Larsen score of radiographic damage. METHODS: Work disability was recorded at onset and at 1, 3, 8, 15 and 20 yr from entry among 103 patients with recent-onset (<6 months) seropositive RA. RESULTS: Work disability due to RA was already 31% [95% confidence interval (CI) 21-40] after 1 yr among patients of working age. It increased gradually and the cumulative rate reached 80% (95% CI 70-89) by the 20 yr check-up. The mean HAQ index was 0.96 at the 20 yr check-up and the mean Larsen score 45% of the maximum value. CONCLUSION: The data serve as a basis of comparison for later cohort studies.

SEM1, a homologue of the split hand/split foot malformation candidate gene Dss1, regulates exocytosis and pseudohyphal differentiation in yeast.

The exocyst is an essential multiprotein complex mediating polarized secretion in yeast. Here we describe a gene, SEM1, that can multicopy-suppress exocyst mutants sec3-2, sec8-9, sec10-2, and sec15-1. SEM1 is highly conserved among eukaryotic species. Its human homologue, DSS1, has been suggested as a candidate gene for the split hand/split foot malformation disorder. SEM1 is not an essential gene. However, its deletion rescued growth of the temperature-sensitive exocyst mutants sec3-2, sec8-9, sec10-1, and sec15-1 at the restrictive temperature. Cell fractionation showed that Sem1p is mainly cytosolic but also associates with the microsomal fraction. In linear sucrose gradients, Sem1p cosedimented with the exocyst component Sec8p. In diploid cells that normally do not form pseudohyphae (S288C background), deletion of SEM1 triggered pseudohyphal growth. This phenotype was abolished after reintroduction of either SEM1 or the mouse homologue Dss1 into the cells. In diploids that have normal capacity for pseudohyphal growth (Sigma1278b background), deletion of SEM1 enhanced filamentous growth. The functionality of both SEM1 and Dss1 in a differentiation process in yeast suggests that Dss1 indeed could be the gene affected in the split hand/split foot malformation disorder. These results characterize SEM1 as a regulator of both exocyst function and pseudohyphal differentiation and suggest a unique link between these two cellular functions in yeast.

Automatic auditory word perception as measured by 40 Hz EEG responses.

OBJECTIVES: Here we report the existence of automatic speech perception in man, revealed by 40 Hz EEG responses. METHODS: We presented to Finnish subjects the Finnish word /tu:li/(wind) as the standard stimulus and another Finnish word /tuli/(fire) as the deviant stimulus using a passive auditory oddball task. The experiment was also conducted with pseudowords as stimuli. RESULTS: We observed a global significant increase in 40 Hz EEG power at 600 ms after stimulus onset for words, but not for pseudowords. CONCLUSIONS: Our results indicate that the memory representation of the standard verbal stimuli, even if unattended, might not merely be based on the physical features of the stimuli: if a semantic representation exists, then the brain processes it pre-attentively.

Protein segregation in peripheral 15 degrees C intermediates in response to caffeine treatment.

Previous studies have shown that caffeine treatment at 20 degrees C causes the intermediate compartment protein p58 to redistribute from the Golgi region without affecting the localization of the Golgi stack protein mannosidase II (J. Jäntti, E. Kuismanen, J. Cell Biol. 120, 1321-1335 (1993). Here we have dissected further the effect of caffeine on transport of Golgi and intermediate compartment proteins from the cell periphery to the perinuclear Golgi region. To accumulate proteins in the peripheral membranes, BHK-21 cells were treated with brefeldin A to redistribute marker proteins towards the ER. Following BFA wash-out and subsequent incubation at 15 degrees C, p58, the coat protein beta-COP, and Man II were all localized in the peripheral 15 degrees C-intermediates. When the cells were shifted from 15 degrees C to 20 degrees C all the proteins were recentralized to the Golgi region. However, if the temperature shift was carried out in the presence of 10 mM caffeine, p58 and beta-COP maintained their peripheral localization, whereas Man II was transported to the Golgi region. The results indicate that caffeine at 20 degrees C does not block the centralization of Man II from peripheral sites to the central Golgi region. Therefore, its effect on ER to Golgi transport appears to be manifested specifically at ER exit. Furthermore, our results indicate that segregation of intermediate compartment and Golgi stack proteins can occur at the level of the peripheral 15 degrees C-intermediates. Immunoelectron microscopic localization of p58 and Man II showed that these peripheral intermediates consisted of tubules and small stacks of cisternae. Within the tubular intermediates both p58 and Man II appeared to segregate to membrane subdomains. Finally, examination of serial and thick sections support the idea that the stacked structures can be generated from tubular intermediates.

Mso1p: a yeast protein that functions in secretion and interacts physically and genetically with Sec1p.

The yeast Sec1p protein functions in the docking of secretory transport vesicles to the plasma membrane. We previously have cloned two yeast genes encoding syntaxins, SSO1 and SSO2, as suppressors of the temperature-sensitive sec1-1 mutation. We now describe a third suppressor of sec1-1, which we call MSO1. Unlike SSO1 and SSO2, MSO1 is specific for sec1 and does not suppress mutations in any other SEC genes. MSO1 encodes a small hydrophilic protein that is enriched in a microsomal membrane fraction. Cells that lack MSO1 are viable, but they accumulate secretory vesicles in the bud, indicating that the terminal step in secretion is partially impaired. Moreover, loss of MSO1 shows synthetic lethality with mutations in SEC1, SEC2, and SEC4, and other synthetic phenotypes with mutations in several other late-acting SEC genes. We further found that Mso1p interacts with Sec1p both in vitro and in the two-hybrid system. These findings suggest that Mso1p is a component of the secretory vesicle docking complex whose function is closely associated with that of Sec1p.

Immunocytochemical analysis of Uukuniemi virus budding compartments: role of the intermediate compartment and the Golgi stack in virus maturation.

Previous studies have suggested that Uukuniemi virus, a bunyavirus, matures at the membranes of the Golgi complex. In this study we have employed immunocytochemical techniques to analyze in detail the budding compartment(s) of the virus. Electron microscopy of infected BHK-21 cells showed that virus particles are found in the cisternae throughout the Golgi stack. Within the cisternae, the virus particles were located preferentially in the dilated rims. This would suggest that virus budding may begin at or before the cis Golgi membranes. The virus budding compartment was studied further by immunoelectron microscopy with a pre-Golgi intermediate compartment marker, p58, and a Golgi stack marker protein, mannosidase II (ManII). Virus particles and budding virus were detected in ManII-positive Golgi stack membranes and, interestingly, in both juxtanuclear and peripheral p58-positive elements of the intermediate compartment. In cells incubated at 15 degrees C the nucleocapsid and virus envelope proteins were seen to accumulate in the intermediate compartment. Immunoelectron microscopy demonstrated that at 15 degrees C the nucleocapsid is associated with membranes that show a characteristic distribution and tubulo-vesicular morphology of the pre-Golgi intermediate compartment. These membranes contained virus particles in the lumen. The results indicate that the first site of formation of Uukuniemi virus particles is the pre-Golgi intermediate compartment and that virus budding continues in the Golgi stack. The results raise questions about the intracellular transport pathway of the virus particles, which are 100 to 120 nm in diameter and are therefore too large to be transported in the 60-nm-diameter vesicles postulated to function in the intra-Golgi transport. The distribution of the virus in the Golgi stack may imply that the cisternae themselves have a role in the vectorial transport of virus particles.

A sec1-related vesicle-transport protein that is expressed predominantly in epithelial cells.

Sec1-related proteins are involved in docking and fusion of transport vesicles in eukaryotic cells. Here we report the cloning and molecular characterization of a Sec1-related protein expressed in the MDCK epithelial cell line. This protein represents a canine counterpart of the murine Munc-18-2/Munc-18b/muSec1 protein, displays 93% amino acid identity with these proteins, has a similar tissue mRNA expression pattern, and associates in vitro with syntaxins 1A, 2, and 3. In situ hybridization analysis of embryonic mouse tissues revealed prominent expression of the munc-18-2 mRNA in the epithelia of several tissues. Cell-fractionation studies demonstrated that the majority of Munc-18-2 is membrane associated. Most of the protein is washed off the membranes by sodium carbonate, pH 11.5. However, the protein is poorly solubilized by detergent treatment. The Munc-18-2 protein was localized, by immunofluorescence microscopy, to the plasma membrane of MDCK cells, and is apically distributed in the epithelial cells of mouse tissues. When overexpressed in COS-1 cells, the protein appeared to be largely cytosolic. However, upon expression with syntaxin 1A, it displayed a shift to the plasma membrane, where the two proteins colocalized. These results identified Munc-18-2 as a predominantly epithelial vesicle-transport protein with a polarized distribution and provided novel in vivo evidence for the association of Sec1-related proteins with members of the syntaxin family.

Membrane insertion and intracellular transport of yeast syntaxin Sso2p in mammalian cells.

Proteins of the syntaxin family are suggested to play a key role in determining the specificity of intracellular membrane fusion events. They belong to the class of membrane proteins which are devoid of N-terminal signal sequence and have a C-terminal membrane anchor. Sso2p is a syntaxin homologue involved in the Golgi to plasma membrane vesicular transport in yeast. The protein was transiently expressed in BHK-21 cells using the Semliki Forest virus vector, and its localization and mode of membrane insertion were studied. By immunofluorescence and immuno-EM we show that Sso2p is transported to its final location, the plasma membrane, along the biosynthetic pathway. Experiments with synchronized Sso2p synthesis or expression of the protein in the presence of brefeldin A indicate endoplasmic reticulum as the initial membrane insertion site. During a 20 degrees C temperature block Sso2p accumulated in the Golgi complex and was chased to the plasma membrane by a subsequent 37 degrees C incubation in the presence of cycloheximide. The in vitro translated protein was able to associate with dog pancreatic microsomes post-translationally. A truncated form of Sso2p lacking the putative membrane anchor was used to show that this sequence is necessary for the membrane insertion in vivo and in vitro. The results show that this syntaxin-like protein does not directly associate with its target membrane but uses the secretory pathway to reach its cellular location, raising interesting questions concerning regulation of SNARE-type protein function.

Production and release of matrix vesicles in the cell processes of TPA-treated human osteoblast-like cells.

At the onset of the mineralization of bone, small membranous matrix vesicles are often observed. The information available on the production and release of these vesicles is limited. When treated with 10-20 nM of the phorbol ester 12-O-tetradecanoyl-phorbol-13-acetate (TPA), the human osteosarcoma cell line U-2 OS developed long cytoplasmic processes connecting adjacent cells. SEM and TEM show that TPA triggers a production and release of matrix vesicle-like membrane vesicles, mainly from the cellular processes. Tetracycline HCl was used to label intracellular bound calcium. The tetracycline HCl label was primarily localized to the end-feet of the cytoplasmic processes, indicating that these contain high concentrations of Ca2+, and to endoplasmic reticulum-like structures in the cell bodies. Together with our previous demonstration of the release of alkaline phosphatase-containing vesicles into the culture medium (Ringbom-Anderson T, Akerman KEO 1992 Calcif Tissue Int 50:533-540), the results presented here indicate that TPA induces a rapid induction of the primary steps of mineralization in U-2 OS osteosarcoma.

Effect of caffeine and reduced temperature (20 degrees C) on the organization of the pre-Golgi and the Golgi stack membranes.

In the present study we have dissected the transport pathways between the ER and the Golgi complex using a recently introduced (Kuismanen, E., J. Jäntti, V. Mäkiranta, and M. Sariola. 1992. J. Cell Sci. 102:505-513) inhibition of transport by caffeine at 20 degrees C. Recovery of the Golgi complex from brefeldin A (BFA) treatment was inhibited by caffeine at reduced temperature (20 degrees C) suggesting that caffeine inhibits the membrane traffic between the ER and the Golgi complex. Caffeine at 20 degrees C did not inhibit the BFA-induced retrograde movement of the Golgi membranes. Further, incubation of the cells in 10 mM caffeine at 20 degrees C had profound effects on the distribution and the organization of the pre-Golgi and the Golgi stack membranes. Caffeine treatment at 20 degrees C resulted in a selective and reversible translocation of the pre- and cis-Golgi marker protein (p58) to the periphery of the cell. This caffeine-induced effect on the Golgi complex was different from that induced by BFA, since mannosidase II, a Golgi stack marker, remained perinuclearly located and the Golgi stack coat protein, beta-COP, was not detached from Golgi membranes in the presence of 10 mM caffeine at 20 degrees C. Electron microscopic analysis showed that, in the presence of caffeine at 20 degrees C, the morphology of the Golgi stack was altered and accumulation of numerous small vesicles in the Golgi region was observed. The results in the present study suggest that caffeine at reduced temperature (20 degrees C) reveals a functional interface between the pre-Golgi and the Golgi stack.

Effect of caffeine on intracellular transport of Semliki Forest virus membrane glycoproteins.

The effect of caffeine on the intracellular transport of Semliki Forest virus (SFV) membrane glycoproteins was studied in baby hamster kidney (BHK) cells. The movement of the proteins was affected at two steps in the exocytic pathway. The exit of the proteins from the endoplasmic reticulum (ER) was inhibited by 10 mM caffeine at 20 degrees C, a temperature that normally allows transport to the Golgi complex. At higher temperatures (28 degrees C and 37 degrees C) in the presence of 10 mM caffeine exit from the ER occurred, but the proteins accumulated at intracellular membrane elements. Immunofluorescence localization, endoglycosidase-H analysis, and analysis of the proteolytical cleavage of the p62 precursor protein suggested that transport in the presence of 10 mM caffeine was arrested at the membranes between the trans-Golgi and the plasma membrane.

Wheat germ agglutinin chromatography of GlcNac beta 1-3(GlcNAc beta 1-6)Gal and GlcNAc beta 1-3(GlcNAc beta 1-6)Gal beta 1-4GlcNAc, obtained by in vitro synthesis and by partial cleavage of teratocarcinoma poly-N-acetyllactosaminoglycans.

GlcNAc beta 1-3(GlcNAc beta 1-6) [14C(U)]Gal and GlcNAc beta 1-3(GlcNAc beta 1-6)[14C(U)]Gal beta 1-4GlcNAc were prepared by in vitro synthesis. They were characterized by enzymatic sequencing, by partial acid hydrolysis, and by periodate oxidation experiments. The two saccharides were isolated also from partial acid hydrolysates of metabolically labeled poly-N-acetyllactosaminoglycans of murine embryonal carcinoma cells (line PC 13). The tetrasaccharide was retarded in a column of agarose-linked wheat germ agglutinin; the trisaccharide was strongly bound. Chromatography in this column separated the trisaccharide into two distinct peaks, which represented interconvertible molecules. Together with our previous data on linear teratocarcinoma saccharides, these findings show that affinity chromatography with immobilized wheat germ agglutinin can be advantageously used in fractionating radiolabeled oligo-N-acetyllactosaminoglycans and saccharides related to them.

Pure red cell aplasia in mixed connective tissue disease.

We describe a patient with mixed connective tissue disease (MCTD), who developed pure red cell aplasia which responded favorably during treatment with corticosteroids. Pure red cell aplasia has been described in a few patients with rheumatoid arthritis and systemic lupus erythematosus, but, to our knowledge, this is the first report of an association between it and MCTD.