Identification of a novel autoantibody reactive with 155 and 140 kDa nuclear proteins in patients with dermatomyositis: an association with malignancy

OBJECTIVE

Myositis-specific autoantibodies (MSAs) are a useful tool in diagnosis, defining clinical subsets and predicting prognosis of dermatomyositis (DM) and polymyositis (PM). In this study, we identified a novel MSA reactive with 155 and 140 kDa nuclear proteins [anti-155/140 antibody (Ab)] and determined the clinical feature of DM patients positive for this autoantibody (autoAb).

METHODS

Sera from 52 Japanese patients with DM, 9 with PM, 48 with systemic lupus erythematosus (SLE), 126 with systemic sclerosis and 18 with idiopathic interstitial pneumonia were examined by immunoprecipitation assays. Positive sera were further characterized by immunodepletion and immunofluorescence staining.

RESULTS

Seven of the 52 (13%) Japanese patients with DM immunoprecipitated 155 and 140 kDa proteins from 35S-labelled K562 leukaemia cell extract. No patients with SLE, systemic sclerosis or idiopathic interstitial pneumonia as well as healthy controls were positive for this autoAb. Patients with anti-155/140 Ab developed heliotrope rash, Gottron's papules or sign and flagellate erythema significantly more frequently than those negative. Notably, internal malignancy was found at significantly higher frequency in those positive than those negative (71 vs 11%; P < 0.005). In contrast, none of these patients positive for this autoAb had interstitial lung disease.

CONCLUSIONS

This novel MSA is associated with cancer-associated DM and may serve as a diagnostic serological marker for this specific subset.

Regulation of local and metastatic host-mediated anti-tumour mechanisms by L-selectin and intercellular adhesion molecule-1

Malignant melanoma is often accompanied by a host response of inflammatory cell infiltration that is highly regulated by multiple adhesion molecules. To assess the role of adhesion molecules, including L-selectin and intercellular adhesion molecule-1 (ICAM-1), in this process, subcutaneous primary growth and metastasis to the lung of B16 melanoma cells not expressing L-selectin, ICAM-1 or their ligands were examined in mice lacking L-selectin, ICAM-1 or both. Primary subcutaneous growth of B16 melanoma was augmented by loss of L-selectin, ICAM-1 or both, while pulmonary metastasis was enhanced by the loss of L-selectin or combined loss of L-selectin and ICAM-1. In both situations, the combined loss of L-selectin and ICAM-1 exhibited the greatest effect. This enhancement was associated generally with a reduced accumulation of natural killer (NK) cells, CD4+ T cells and CD8+ T cells and also with a diminished release of interferon (IFN)-gamma and tumour necrosis factor (TNF)-alpha but not interleukin (IL)-6. Cytotoxicity against melanoma was not defective by the absence of ICAM-1, L-selectin or both, suggesting that the enhancement of tumour growth and metastasis caused by the loss of adhesion molecules results from an impaired migration of effector cells into the tissue rather than from a suppression of the cytotoxic response. The results indicate that L-selectin and ICAM-1 contribute co-operatively to the anti-tumour reaction by regulating lymphocyte infiltration to the tumour.

Serum levels of monocyte chemotactic protein-3/CCL7 are raised in patients with systemic sclerosis: association with extent of skin sclerosis and severity of pulmonary fibrosis

OBJECTIVE

To determine serum levels of monocyte chemotactic protein-3 (MCP-3) and its clinical associations in patients with systemic sclerosis (SSc).

METHODS

Serum MCP-3 levels from 69 patients with SSc were examined by ELISA.

RESULTS

Serum MCP-3 levels were raised in patients with SSc (n = 69) compared with healthy controls (n = 28). Patients with diffuse cutaneous SSc (n = 36) had higher levels of serum MCP-3 than those with limited cutaneous SSc (n = 33). Patients with raised MCP-3 levels had pulmonary fibrosis and decreased vital capacity (VC) more often than those with normal MCP-3 levels. MCP-3 levels correlated positively with the extent of skin fibrosis, and inversely with %VC and carbon monoxide transfer factor (Tlco) in patients with SSc.

CONCLUSION

MCP-3 levels were increased in patients with SSc, and correlated with the extent of skin sclerosis and the severity of pulmonary fibrosis. These results suggest that MCP-3 may have a role in the development of fibrosis in SSc.

Analysing mass balance of viruses in a coagulation-ceramic microfiltration hybrid system by a combination of the polymerase chain reaction (PCR) method and the plaque forming units (PFU) method

Virus removal experiments using river water spiked with bacteriophages were conducted by an in-line coagulation-ceramic microfiltration hybrid system to investigate the effects of filtration flux (62.5 and 125 L/(m2 x h)) and type of virus (Qbeta and MS2) on virus removal. In addition, the mass balance of viruses through the hybrid system was analysed by quantifying the infectious and inactive viruses by a combination of the polymerase chain reaction (PCR) method and the plaque forming units (PFU) method. Even when the system was operated at high filtration flux (125 L/(m2 x h)), high virus removal (> 6 log) with short coagulation time (2.4 s) was successfully achieved by dosing polyaluminium chloride (PACI) at more than 1.08 mg-Al/L. Removal performances were different between Qbeta and MS2, although their diameters are almost the same: greater virus removal was achieved for MS2 at PACI dosing of 0.54 mg-Al/L, and for Qbeta at PACI dosing of more than 1.08 mg-Al/L. The combination of the PCR and PFU methods revealed that two phenomena, adsorption to/entrapment in aluminium floc and virucidal activity of PACI, partially account for the high virus removal in the coagulation-MF hybrid system.

Ligating properties of a potentially tetradentate Schiff base [(CH3)2NCH2CH2NCHC6H3(OH)(OMe)] with zinc(ii), cadmium(ii), cobalt(ii), cobalt(iii) and manganese(iii) ions: synthesis and structural studies

A series of Zn(II), Cd(II), Co(II), Co(III) and Mn(III) complexes with the Schiff base [(CH3)2NCH2CH2N=CHC6H3(OH)(OMe)], LH, derived from 2-dimethylaminoethylamine and o-vanillin, has been synthesised and structures of all the products have been established by X-ray crystallography. In the cases of zinc and cadmium, dimeric complexes [Zn(LH)2(NCS)] [Zn2(L)(mu(1,1)-CH3COO)(NCS)3] (1), [Cd2(L)2(Cl)2] (2) and [Cd2(L)2(NCS)2] (3), and for cobalt and manganese, monomeric complexes [Co(LH)2(NCS)]2 [Co(NCS)4] (4), [Co(LH)2(NCS)]ClO4 (5), [Co(L)(N3)(o-vanillinate)] x 0.5 MeOH (6) and [Mn(LH)2(MeOH)2](ClO4)3 (7), are formed with various terminal ligands. All the complexes have been characterised by elemental analysis and IR spectra. UV-Vis and NMR spectroscopy, magnetic, and electrochemical studies, were also carried out where feasible. The Schiff base functions as a bi-, tri- or tetra-dentate chelating agent and coordinates via the protonated or deprotonated phenolic oxygen, amine and imine nitrogens, and only in case of 1 with the methoxy oxygen atoms, to the metal ion leading to the formation of mono- or bi-metallic complexes.

A novel neuronal cell line derived from the ventrolateral region of the suprachiasmatic nucleus

The suprachiasmatic nucleus of the anterior hypothalamus is the center of an internal biological clock in mammals. Glutamate is the neurotransmitter of retino-hypothalamic tract responsible for mediating the circadian actions of light in rodents. N-methyl-d-aspartate receptors, particularly NR2B subunit are reported to be principally involved in photic resetting of the biological clock in vivo and in slice culture. But, the precise cellular mechanisms of the resetting are not elucidated, because no adequate neuronal cell lines derived from the suprachiasmatic nucleus have been established. We established a neuronal cell line, N14.5, derived from the suprachiasmatic nucleus of a transgenic rat harboring the temperature-sensitive simian virus 40 large T-antigen gene. When the cells were cultured at 39 degrees C, the morphological features were turned fibroblastic into neuronal round cell body with neurite extensions. These cells showed immunoreactivities for neuronal markers (betaIII-tubulin, microtubule-associated protein 2 and TAU2) and as well as for vasoactive intestinal peptide which is expressed in the ventrolateral region of the suprachiasmatic nucleus. The cells expressed N-methyl-d-aspartate receptors, particularly NR1 and NR2B subunits as revealed by quantitative PCR. N-methyl-d-aspartate activated phosphorylation of p44/42 mitogen-activated protein kinase and increased expression level of Per1 and Per2 mRNA. These results suggest that the N14.5 is a novel neuronal cell line derived from the ventrolateral region of the suprachiasmatic nucleus, and that N-methyl-d-aspartate receptors expressed in the cells are a functional receptor. The N14.5 cells may be a useful tool to elucidate numerous chronobiological processes, especially resetting mechanism induced by an external light signal.

Fatal thrombosis of antithrombin-deficient mice is rescued differently in the heart and liver by intercrossing with low tissue factor mice

BACKGROUND

We previously reported that the targeted disruption of murine antithrombin (AT) gene resulted in embryonic lethality before 16.5 gestational days (gd) because of severe cardiac and hepatic thrombosis.

OBJECTIVE AND METHODS

To investigate the influences of lowered tissue factor (TF) activity upon hypercoagulation of AT-/- embryos, we crossed AT+/- with low TF (mTF-/- hTF+) mice to yield homozygous AT-deficient mice with the extremely low TF activity, that is expressed from the inserted human TF mini gene.

RESULTS

AT-/- embryos either with 50% TF (AT-/- mTF+/- hTF+) or with low (approximately 1% TF, AT-/- mTF-/- hTF+) were not born, although the survival was prolonged until 18.5 gd. In both genotypes, histological examination showed disseminated thrombosis in hepatic sinusoidal space or in the portal veins, suggesting that the thrombogenesis caused loss of hepatic blood flow. As in original AT-/-, AT-/- mTF+/- hTF+ showed subcutaneous (s.c.) bleeding and also suffered from the myocardial degeneration apparently because of coronary thrombus formation. However, AT-/- mTF-/- hTF+ had no skin hemorrhage and the thrombosis and degeneration were completely abolished in the heart. Myocardium of adult low TF mice had exhibited fibrosis secondary to hemorrhage; however, it was significantly decreased in low TF mice with AT+/-.

CONCLUSIONS

Our current model suggests that, in the heart, TF plays an important role in the thrombogenesis and it counterbalances AT-dependent anticoagulation. AT may be a potent anticoagulant during mice development and the activation and subsequent regulation of TF-procoagulant activity take place differently between the liver and the heart. These differences appear to point to local regulatory mechanisms in murine hemostasis.

Anti-phosphatidylserine-prothrombin complex antibodies in patients with localized scleroderma

OBJECTIVE

Although some antiphospholipid antibodies (Abs) are found in patients with localized scleroderma (LSc), Ab against phosphatidylserine-prothrombin complex (PS/PT) has not been examined. We investigated anti-PS/PT Ab levels in patients with LSc.

METHODS

IgG anti-PS/PT Ab levels in serum samples taken from patients with LSc (n = 42) were measured using ELISA.

RESULTS

IgG anti-PS/PT Ab was detected in 17% of the LSc patients, while it was not detected in any normal controls (n = 32) or psoriasis vulgaris (n = 25), and this frequency was similar to that of systemic sclerosis (17%, n = 41). Among 3 LSc subgroups, generalized morphea, the severest form of LSc, had a frequency (27%) comparable with that of systemic lupus erythematosus (32%, n = 25). Among 7 LSc patients with anti-PS/PT Ab, 2 developed symptomatic thromboembolism (A 70-year-old man developed deep vein thrombosis and pulmonary infarction, although he was negative for other antiphospholipid Abs. A 6-year-old boy positive for lupus anticoagulant had cerebral infarction). By contrast, symptomatic thromboembolism was not detected in 35 LSc patients without anti-PS/PT Ab.

CONCLUSION

Patients with LSc, especially generalized morphea, exhibit anti-PS/PT Ab at a frequency comparable with collagen diseases such as systemic sclerosis and systemic lupus erythematosis. Examination of this Ab may be useful to recognize the risk of thromboembolism in patients with LSc.

Screening level analysis for monitoring pesticide in river water using a hydrological diffuse pollution model with limited input data

To predict rice-farming pesticide concentrations in river water with imprecise model inputs for screening-level analysis, a basin-scale runoff model was developed. The Monte Carlo method was applied to create estimates of input data regarding agricultural work schedules and parameters for pesticide decomposition and sorption in solids and water. The prediction accuracy of the model was evaluated when used with non-optimised pesticide parameters; the model was calibrated using hydrological data alone without reference to observed pesticide concentration data. Overall, predictions for the pesticide concentrations were successful within order-of-magnitude accuracy. The pesticide rankings according to the predicted concentration roughly agreed with those observed. The success of screening-level analysis indicates that the model prediction can help in selection of pesticides to be monitored and in determining the monitoring schedule for the river basin.

Origin of the metallic properties of heavily boron-doped superconducting diamond

The physical properties of lightly doped semiconductors are well described by electronic band-structure calculations and impurity energy levels. Such properties form the basis of present-day semiconductor technology. If the doping concentration n exceeds a critical value n(c), the system passes through an insulator-to-metal transition and exhibits metallic behaviour; this is widely accepted to occur as a consequence of the impurity levels merging to form energy bands. However, the electronic structure of semiconductors doped beyond n(c) have not been explored in detail. Therefore, the recent observation of superconductivity emerging near the insulator-to-metal transition in heavily boron-doped diamond has stimulated a discussion on the fundamental origin of the metallic states responsible for the superconductivity. Two approaches have been adopted for describing this metallic state: the introduction of charge carriers into either the impurity bands or the intrinsic diamond bands. Here we show experimentally that the doping-dependent occupied electronic structures are consistent with the diamond bands, indicating that holes in the diamond bands play an essential part in determining the metallic nature of the heavily boron-doped diamond superconductor. This supports the diamond band approach and related predictions, including the possibility of achieving dopant-induced superconductivity in silicon and germanium. It should also provide a foundation for the possible development of diamond-based devices.

Semen quality of 324 fertile Japanese men

BACKGROUND

A number of studies have indicated regional differences in semen quality. To examine the current status in Japan, we undertook a cross-sectional study on the semen quality of fertile Japanese men for comparison with recent European results.

METHODS

Semen parameters of 324 fertile men from the Kawasaki/Yokohama area were investigated. The semen parameters were compared with those published for fertile men from four European cities, Copenhagen, Paris, Edinburgh and Turku.

RESULTS

When adjusting for confounders such as ejaculation abstinence period and age, the lowest sperm concentrations were detected in men from Kawasaki/Yokohama followed by men from Copenhagen, Paris, Edinburgh and Turku, but only the differences between men from Kawasaki/Yokohama and men from Edinburgh and Turku were significant (P=0.0008 and P<0.0001, respectively). Total sperm count, percentage of motile sperm and percentage of normal sperm observed in Kawasaki/Yokohama were significantly lower than those from all European centres except for motile sperm in men from Paris.

CONCLUSIONS

Japanese fertile men had a semen quality at the level of Danish men, who have been reported to have the lowest among investigated men in Europe. The low level of semen quality of the fertile Japanese men may be due to lifestyle or other environmental factors; however, ethnic differences caused by different genetic variation or combinations cannot be ruled out by this study.

A novel oligodendrocyte cell line OLP6 shows the successive stages of oligodendrocyte development: late progenitor, immature and mature stages

The successive stages of development from oligodendrocyte progenitor to mature oligodendrocyte have been investigated in detail by using stage-specific antibodies. However, no cell lines are available that show stepwise differentiation from oligodendrocyte progenitors to mature oligodendrocytes. Here we show the establishment of an immortalized oligodendrocyte cell line, OLP6, from adult transgenic rats harboring the temperature-sensitive simian virus 40 large T-antigen gene. The OLP6 cells had a fibroblastic morphology and continuously proliferated at 33 degrees C. They displayed growth arrest and multipolar morphology when they were cultured at 39 degrees C. They express the oligodendrocytic markers O4, 2'-3'-cyclic-nucleotide 3'-phosphodiesterase, galactocerebroside and second endothelial differentiation gene receptor-2 at 39 degrees C. The OLP6 cells underwent apoptosis upon serum withdrawal at 39 degrees C. Lysophosphatidic acid inhibited this apoptosis and promoted the expression of myelin basic protein. These results demonstrate that the activation of endothelial differentiation gene receptor-2 exerts anti-apoptosis and myelinogenesis effects on the OLP6 cells. Taken together, the OLP6 cells in the late oligodendrocyte progenitor stage can progress to the immature oligodendrocyte stage by shifting culture temperature. Furthermore, lysophosphatidic acid promoted the maturation of OLP6 cells in the immature oligodendrocyte stage. Such OLP6 cells should provide a potent model system for studying the precise mechanism involved in stepwise differentiation of oligodendrocytes.

Obesity enhances the induction of plasminogen activator inhibitor-1 by restraint stress: a possible mechanism of stress-induced renal fibrin deposition in obese mice

BACKGROUND AND OBJECTIVES

Cardiovascular/thrombotic diseases are frequently induced by a variety of stressors. Obese patients are susceptible to thrombotic diseases associated with stress, but the underlying mechanism is still unknown. We have begun to investigate the expression of a primary inhibitor of fibrinolysis, plasminogen activator inhibitor-1 (PAI-1), in association with tissue thrombosis, using restraint-stressed obese mice.

METHODS AND RESULTS

We analyzed the expression of PAI-1 after restraint (immobilization) stress in genetically obese mice in comparison with their lean counterparts. Dramatic increases in PAI-1 antigen in plasma and in tissue extracts were observed in the obese mice exposed to restraint stress. The induction of PAI-1 mRNA by stress in the tissues was also pronounced in the stressed obese mice as compared with the lean mice, especially in the hearts and adipose tissues. In situ hybridization analysis revealed that strong signals for PAI-1 mRNA were localized in the adipocytes, cardiovascular endothelial cells, and renal glomerular cells of the stressed obese mice. Histological examination revealed that renal glomerular fibrin deposition was detected only in the obese mice after 2 h of restraint stress.

CONCLUSIONS

Obesity enhances the stress-mediated PAI-1 induction in the blood and tissues. This phenomenon may be associated with the increased risk of stress-induced renal fibrin deposition in obese subjects.

Cyclic tensile stretch stimulates the release of reactive oxygen species from osteoblast-like cells

It is known that the excessive generation of reactive oxygen species (ROS) is a significant factor in tissue injury observed in many disease states. To determine whether extreme levels of mechanical stress applied to osteoblasts enhances ROS synthesis, we loaded cyclic tensile stretch on osteoblast-like HT-3 cells. Cyclic tensile stretch loaded on these cells clearly enhanced ROS synthesis in a time- and magnitude-dependent fashion. Cyclic tensile stretch also enhanced superoxide dismutase (SOD) activity. The disruption of microfilaments with cytochalasin D abolished the stress-induced ROS synthesis. Rotenone, an inhibitor of the mitochondrial electron transport chain, enhanced stress-induced ROS synthesis. These data suggest that actin filament and mitochondria are involved in this action.

Increased cutaneous T-cell-attracting chemokine levels in sera from patients with systemic sclerosis

OBJECTIVE

We sought to assess serum cutaneous T-cell-attracting chemokine (CTACK) levels and CTACK expression levels in skin from patients with systemic sclerosis (SSc), and determine whether serum CTACK levels correlate with clinical features in SSc patients.

METHODS

Serum samples were obtained from 73 SSc patients, 32 patients with systemic lupus erythematosus and 26 patients with dermatomyositis. Serum CTACK levels were determined by enzyme-linked immunoabsorbent assay. CTACK mRNA expression in sclerotic skin was assessed by real-time reverse transcription-polymerase chain reaction.

RESULTS

Serum CTACK levels were significantly increased in patients with diffuse cutaneous SSc (dSSc; n=32) and those with limited cutaneous SSc (lSSc; n=41) compared with normal controls (n=31; P<0.05 and P<0.0005, respectively). The presence of calcinosis and muscle involvement was more frequently detected in SSc patients with elevated CTACK levels (P<0.05 and P<0.05, respectively). Elevated C-reactive protein levels were also observed more frequently in SSc patients with increased CTACK levels (P<0.05). CTACK mRNA expression levels in the sclerotic skin of SSc patients were augmented. In a longitudinal study, serum CTACK levels were generally decreased during the follow-up.

CONCLUSIONS

The increased serum CTACK levels and enhanced skin CTACK expression in SSc patients suggest that CTACK is related to the inflammation associated with SSc.

Adeno-associated virus vector-mediated interleukin-10 gene transfer inhibits atherosclerosis in apolipoprotein E-deficient mice

Inflammation is a major contributor to atherosclerosis by its effects on arterial wall biology and lipoprotein metabolism. Interleukin-10 (IL-10) is an anti-inflammatory cytokine that may modulate the atherosclerotic disease process. We investigated the effects of adeno-associated virus (AAV) vector-mediated gene transfer of IL-10 on atherogenesis in apolipoprotein E (ApoE)-deficient mice. A murine myoblast cell line, C2C12, transduced with AAV encoding murine IL-10 (AAV2-mIL10) secreted substantial amounts of IL-10 into conditioned medium. The production of monocyte chemoattractant protein-1 (MCP-1) by the murine macrophage cell line, J774, was significantly inhibited by conditioned medium from AAV2-mIL10-transduced C2C12 cells. ApoE-deficient mice were injected with AAV5-mIL10 into their anterior tibial muscle at 8 weeks of age. The expression of MCP-1 in the vascular wall of the ascending aorta and serum MCP-1 concentration were decreased in AAV5-mIL10-transduced mice compared with AAV5-LacZ-transduced mice. Oil red-O staining of the ascending aorta revealed that IL-10 gene transfer resulted in a 31% reduction in plaque surface area. Serum cholesterol concentrations were also significantly reduced in AAV5-mIL10-transduced mice. To understand the cholesterol-lowering mechanism of IL-10, we measured the cellular cholesterol level in HepG2 cells, resulting in its significant decrease by the addition of IL-10 in a dose-dependent manner. Furthermore, IL-10 suppressed HMG-CoA reductase expression in the HepG2 cells. These observations suggest that intramuscular injection of AAV5-mIL10 into ApoE-deficient mice inhibits atherogenesis through anti-inflammatory and cholesterol-lowering effects.

Rapid adsorption pretreatment with submicrometre powdered activated carbon particles before microfiltration

Manufacturer-supplied powdered activated carbon (PAC) was ground to produce submicrometre particles (0.8 and 0.6 m median diameter) for use as an adsorbent before microfiltration (MF) for drinking water treatment. Batch tests revealed that the microground PAC adsorbed natural organic matter (NOM) much more rapidly and had a higher adsorptive capacity than ordinary PAC. The water samples pretreated with the submicrometre PAC were subjected to MF, and the results of experiments with different PAC contact times revealed that a 1 min retention time was sufficient for adsorptive removal of NOM. The use of submicrometre PAC permitted not only shorter PAC contact times but also a 75% reduction in dose.

Effect of uncertainties in agricultural working schedules and Monte-Carlo evaluation of the model input in basin-scale runoff model analysis of herbicides

In the prediction of time-series concentrations of herbicides in river water with diffuse-pollution hydrological models, farming schedules (the dates of herbicide application and drainage of irrigation water from rice paddies) greatly affect the runoff behavior of the herbicides. For large catchments, obtaining precise data on farming schedules is impractical, and so the model input inevitably includes substantial uncertainty. This paper evaluates the effectiveness of using the Monte-Carlo method to generate sets of estimated farming schedules to use as input to a GIS-based basin-scale runoff model to predict the concentrations of paddy-farming herbicides in river water. The effects of using the Monte-Carlo method to compensate for uncertainty in the evaluated parameters for herbicide decomposition and sorption were also evaluated.

Autoantibody against matrix metalloproteinase-3 in patients with systemic sclerosis

Systemic sclerosis (SSc) is characterized by multi-organ fibrosis with an autoimmune background. Although autoantibodies are detected frequently in SSc patients, the role of autoantibody in the development of fibrosis remains unknown. Connective tissue homeostasis is a balance between the synthesis and degradation of the extracellular matrix (ECM); ECM degradation is regulated mainly by matrix metalloproteinases (MMPs). Anti-MMP-1 antibody is suggested to inhibit MMP-1 and be involved in the development of the fibrosis in SSc. However, the accumulation of various ECM components in the tissue of SSc cannot be explained by the anti-MMP-1 antibody alone. In this study, we examined the presence or levels of antibody to MMP-3, a protein which degrades various ECM components relevant to SSc fibrosis. Enzyme-linked immunosorbent assay (ELISA) using human recombinant MMP-3 revealed that IgG anti-MMP-3 autoantibody levels were elevated significantly in the sera from SSc patients, but not in patients with active systemic lupus erythematosus or dermatomyositis. IgG and IgM anti-MMP-3 antibody levels were significantly higher in diffuse cutaneous SSc, a severe form, than those in limited cutaneous SSc. Consistently, IgG anti-MMP-3 antibody levels correlated significantly with fibrosis of the skin, lung and renal blood vessels. The presence of IgG anti-MMP-3 autoantibody in sera from SSc patients was confirmed by immunoblotting analysis. Remarkably, MMP-3 activity was inhibited by IgG anti-MMP-3 antibody. These results suggest that anti-MMP-3 antibody is a serological marker that reflects the severity of SSc and also suggest that it may contribute to the development of fibrosis by inhibiting MMP-3 activity and reducing the ECM turnover.

Hypoxia-induced nitric oxide protects chondrocytes from damage by hydrogen peroxide

OBJECTIVE

Because articular cartilage has no vascular supply, chondrocytes are hypoxic under normal physiological conditions. Nitric oxide (NO) plays an important role in chondrocyte damage, such as apoptosis. Although oxygen stress with hydrogen peroxide was found to cause chondrocyte damage, these data were obtained under normoxic (21% O2) conditions. We investigated the effects of hypoxia on hydrogen peroxide-induced chondrocyte damage

METHODS

Bovine articular chondrocytes were used in this study. Proteoglycan (PG) synthesis and the induction of apoptosis were analyzed with [(35)S]-sulfate incorporation and annexin V staining, respectively. The induction of NO was examined using a fluorescent probe and RT-PCR.

RESULTS

Cells maintained at 5% O2 had the maximum PG synthesis. Under normoxic conditions, hydrogen peroxide inhibited PG synthesis and induced annexin V positive cells in a dose-dependent fashion. However, in those cells cultured under hypoxic (5%) conditions, the hydrogen peroxide-induced annexin V expression was attenuated. Chondrocytes exposed to hypoxia showed induction of NO. When the hypoxia-induced NO was inhibited, the hypoxia-enhanced PG synthesis was abolished and hydrogen peroxide clearly induced cell damage.

CONCLUSIONS

Endogenous NO induced by hypoxia protects chondrocytes from apoptosis induced by an oxidative stress.

Mini-incision posterior approach for total hip arthroplasty

We compared the short-term outcomes of 50 total hip arthroplasties performed through a mini-incision posterior approach with those of 42 arthroplasties performed through a conventional posterior approach. There were no significant differences in age, gender, and bodymass index between groups. The mean operative time was shorter (99+/-26 versus 123+/-30 min), and the peroperative mean blood loss was smaller with the mini-incision (339+/-210 versus 422+/-177 ml). There was no significant difference between groups in post-operative mean blood loss, mean inclination angle of acetabular components, percentage of hips with good inclination angle, and mean hip score at 6 months after surgery. There was one infection in the conventional group but none in the mini group. There were no dislocations or symptomatic pulmonary embolism in either group. With the mini-incision posterior approach, surgical invasion was reduced, and short-term outcome was as good as with a conventional posterior approach.

Serum soluble CTLA-4 levels are increased in diffuse cutaneous systemic sclerosis

OBJECTIVE

To determine serum levels of soluble cytotoxic T-lymphocyte associated molecule-4 (sCTLA-4) and clinical association in patients with systemic sclerosis (SSc).

METHODS

Serum sCTLA-4 levels from 32 patients with diffuse cutaneous SSc (dSSc) and 27 patients with limited cutaneous SSc (lSSc) were examined by enzyme-linked immunosorbent assay (ELISA). For a longitudinal study, 211 sera from 30 SSc patients were analysed (follow-up 2.1-7.0 yr).

RESULTS

Serum sCTLA-4 levels were elevated in dSSc patients compared with normal controls (n = 41), lSSc patients and patients with active systemic lupus erythematosus (SLE) (n = 23). By contrast, sCTLA-4 levels in patients with lSSc or SLE were normal. SSc patients with elevated sCTLA-4 levels had a shorter disease duration and more frequent presence of digital pitting scars, contracture of phalanges, diffuse pigmentation, pulmonary fibrosis and decreased percentage vital capacity (%VC) than those with normal sCTLA-4 levels. sCTLA-4 levels correlated positively with the extent of skin fibrosis, serum IgG levels and anti-topoisomerase I antibody levels. In a longitudinal study, sCTLA-4 levels decreased on a parallel with improvement of skin sclerosis in five dSSc patients. Skin sclerosis did not improve in two of six dSSc patients with high sCTLA-4 levels throughout the follow-up, while the remaining four patients showed improvement of skin sclerosis.

CONCLUSION

These results suggest that sCTLA-4 correlates with disease severity and activity of SSc and that sCTLA-4 plays a role in immunological abnormalities of SSc, since sCTLA-4 may augment humoral immune responses as well as T-cell responses by interfering with B7-CTLA-4 interactions that induce negative signals in T and B cells.