Raynaud's phenomenon: its relevance to scleroderma

Characterization of Long Non-Coding RNAs in Systemic Sclerosis Monocytes: A Potential Role for PSMB8-AS1 in Altered Cytokine Secretion

Systemic sclerosis (SSc) is a chronic autoimmune disease mainly affecting the connective tissue. In SSc patients, monocytes are increased in circulation, infiltrate affected tissues, and show a pro-inflammatory activation status, including the so-called interferon (IFN) signature. We previously demonstrated that the dysregulation of the IFN response in SSc monocytes is sustained by altered epigenetic factors as well as by upregulation of the long non-coding RNA (lncRNA) NRIR. Considering the enormously diverse molecular functions of lncRNAs in immune regulation, the present study investigated the genome-wide profile of lncRNAs in SSc monocytes, with the aim to further unravel their possible role in monocyte dysregulation and disease pathogenesis. Transcriptomic data from two independent cohorts of SSc patients identified 886 lncRNAs with an altered expression in SSc monocytes. Differentially expressed lncRNAs were correlated with neighboring protein coding genes implicated in the regulation of IFN responses and apoptotic signaling in SSc monocytes. In parallel, gene co-expression network analysis identified the lncRNA PSMB8-AS1 as a top-ranking hub gene in co-expression modules implicated in cell activation and response to viral and external stimuli. Functional characterization of PSMB8-AS1 in monocytes demonstrated that this lncRNA is involved in the secretion of IL-6 and TNFα, two pivotal pro-inflammatory cytokines altered in the circulation of SSc patients and associated with fibrosis and disease severity. Collectively, our data showed that lncRNAs are linked to monocyte dysregulation in SSc, and highlight their potential contribution to disease pathogenesis.

The patient experience of Raynaud's phenomenon in systemic sclerosis

RP is the most common manifestation of SSc and a major cause of disease-related morbidity. This review provides a detailed appraisal of the patient experience of SSc-RP and potential implications for disease classification, patient-reported outcome instrument development and SSc-RP clinical trial design. The review explores the clinical features of SSc-RP, the severity and burden of SSc-RP symptoms and the impact of SSc-RP on function, work and social participation, body image dissatisfaction and health-related quality of life in SSc. Where management of SSc-RP is concerned, the review focuses on the 'patient experience' of interventions for SSc-RP, examining geographic variation in clinical practice and potential barriers to the adoption of treatment recommendations concerning best-practice management of SSc-RP. Knowledge gaps are highlighted that could form the focus of future research. A more thorough understanding of the patient experience could support the development of novel reported outcome instruments for assessing SSc-RP.

Expression of the oxygen-sensitive transcription factor subunit HIF-1α in patients suffering from secondary Raynaud syndrome

Anti-ischemic therapy remains a challenge due to the complexity of hypoxia response pathways. Hypoxia-inducible factor (HIF)-1 is a heterodimer transcription factor consisting of 2 subunits, HIF-1α and HIF-1β. Hypoxia-dependent activation of HIF-1α regulates cellular O₂ homeostasis. Raynaud syndrome (RS), as a comorbidity of the autoimmune disease systemic sclerosis (SS), is characterized by vasospasms that limit blood flow to the limbs, resulting in hypoxia. A single-center randomized study was conducted to compare prostaglandin E1 (PgE1) therapy with a treatment combining PgE1 and an endothelin-1 blocker, bosentan. A total of 30 patients suffering from SS with RS were enrolled. We examined the regulation of HIF-1α, its target heme oxygenase-1 (HMOX-1), and the serum levels of the HIF-1α protein in a subset of patients as well as in ten healthy individuals. The expression of HIF-1α and HMOX-1 in monocytes was measured using absolute plasmid-based quantitative real-time PCR, whereas serum HIF-1α levels were measured with ELISA. Samples were taken at the time of randomization and after 24 weeks. We found that HIF-1α and HMOX-1 mRNA expression in monocytes and serum HIF-1α protein levels were significantly higher in the SS/RS patients compared to the healthy control group. Single-drug therapy significantly increased HIF-1α and HMOX-1 mRNA expression in monocytes and serum HIF-1α protein levels in the SS/RS patients compared to those at the time of randomization, whereas combining PgE1 with an endothelin-1 blocker prevented the further increases in HIF-1α and HMOX-1 expression. We propose HIF-1α and HMOX-1 as novel markers for anti-ischemic therapy in RS.

From microvasculature to fibroblasts: Contribution of anti-endothelial cell antibodies in systemic sclerosis

Systemic sclerosis (SSc) is an autoimmune disease characterized by skin and internal organ fibrosis, caused by microvascular dysfunction. In recent years, the hypothesis that anti-endothelial cell antibodies (AECA) play a key role in microvascular damage seems to be increasingly convincing. In fact, AECA can induce antibody-dependent cellular apoptosis and stimulate the microvasculature to release pro-inflammatory and pro-fibrotic cytokines. Human-microvascular-endothelial-cells (MVECs) were stimulated with SSc sera (with and without AECA) and with sera from healthy donors. The conditioned MVEC culture media were then added to fibroblast cultures obtained from control skin (CTR), non-affected skin of SSc patients (NA), and affected skin of the same sclerodermic (SSc) patients, respectively. AECA contributed to the MVEC increased release of endothelin-1 (ET-1) in the culture medium and to MVEC apoptosis. Fibroblast (CTR, NA, and SSc) proliferation was increased after treatment with AECA-positive conditioned media, compared to AECA-negative and control conditioned media. Furthermore, both AECA-positive (in major contribution) and AECA-negative conditioned media were responsible for alpha-smooth-muscle-actin (αSMA) over-expression in all fibroblast cultures, compared to control conditioned media. Fibroblast type I collagen synthesis was upregulated by both SSc conditioned media (with and without AECA). Finally, the synthesis of fibroblast transforming-growth-factor-beta (TGF-β) was statistically higher in AECA-positive conditioned media, compared to AECA-negative and control conditioned media. These findings support the concept that AECA may mediate the crosstalk between endothelial damage and dermal-fibroblast activation in SSc.

The isolation and characterization of systemic sclerosis vascular smooth muscle cells: enhanced proliferation and apoptosis resistance

Background

Vascular dysfunction is a major pathologic component of systemic sclerosis (SSc). The role of vascular smooth muscle cells (vSMCs) in the development of vascular dysfunction is still unknown. In this study, we describe a method for isolation of dermal vSMCs from skin biopsies, and we outline their functional phenotype.

Methods

We obtained 4 mm punch-skin biopsies from three SSc patients and matched controls. After trypsin digestion, cells were cultured for 14 days. vSMCs were isolated by first depleting CD31+ cells (endothelial cells), followed by positive selection of CD146+ cells. The CD31- CD146+ cells were then cultured in media optimized for SMCs proliferation. We evaluated cell proliferation, viability and apoptosis in normal and in low serum culture conditions. Cytoplasmic and nuclear expression levels of β-catenin were also investigated.

Results

The CD31- CD146+ cell population expressed smooth muscle MYH11, Desmin and Vimentin but did not express NG2. Flow cytometry confirmed the high purity of CD31- CD146+ MYHC11+ cell population that was maintained for up to the eleventh passage. SSc-vSMCs exhibited increased cell proliferation and viability compared to control cells. Under serum starvation conditions, SSc-vSMCs exhibited more proliferative capacity, and resistance to apoptosis compared to control-vSMCs. Furthermore, a cytoplasmic to nuclear translocation of β-catenin was seen in SSc-vSMCs but not in control-vSMCs.

Conclusions

This is the first report of successful isolation and initial characterization of SSc-vSMCs. It is likely that increased proliferation of SSc-vSMCs in association with resistance to apoptosis can adversely impact the vascular lesion in SSc.

International consensus criteria for the diagnosis of Raynaud's phenomenon

Vasoconstriction accompanied by changes in skin color is a normal physiologic response to cold. The distinction between this normal physiology and Raynaud's phenomenon (RP) has yet to be well characterized. In anticipation of the 9th International Congress on Autoimmunity, a panel of 12 RP experts from 9 different institutes and four different countries were assembled for a Delphi exercise to establish new diagnostic criteria for RP. Relevant investigators with highly cited manuscripts in Raynaud's-related research were identified using the Web of Science and invited to participate. Surveys at each stage were administered to participants via the on-line SurveyMonkey software tool. The participants evaluated the level of appropriateness of statements using a scale of 1 (extremely inappropriate) through 9 (extremely appropriate). In the second stage, panel participants were asked to rank rewritten items from the first round that were scored as "uncertain" for the diagnosis of RP, items with significant disagreement (Disagreement Index > 1), and new items suggested by the panel. Results were analyzed using the Interpercentile Range Adjusted for Symmetry (IPRAS) method. A 3-Step Approach to diagnose RP was then developed using items the panelists "agreed" were "appropriate" diagnostic criteria. In the final stage, the panel was presented with the newly developed diagnostic criteria and asked to rate them against previous models. Following the first two iterations of the Delphi exercise, the panel of 12 experts agreed that 36 of the items were "appropriate", 12 items had "uncertain" appropriateness, and 13 items were "inappropriate" to use in the diagnostic criteria of RP. Using an expert committee, we developed a 3-Step Approach for the diagnosis of RP and 5 additional criteria for the diagnosis of primary RP. The committee came to an agreement that the proposed criteria were "appropriate and accurate" for use by physicians to diagnose patients with RP.

Finger thermoregulatory model assessing functional impairment in Raynaud's phenomenon

Raynaud's Phenomenon (RP) is a paroxysmal vasospastic disorder of small arteries, pre-capillary arteries, and cutaneous arteriovenous shunts of the extremities, typically induced by cold exposure and emotional stress. RP is either primary (PRP) or secondary to systemic sclerosis. In this study we use Control System Theory to model finger thermoregulatory processes in response to a standardized cold challenge (a diagnostic test routinely performed for differential diagnosis of RP). The proposed model is based on a homeostatic negative feedback loop, characterized by five distinct parameters which describe how the control mechanisms are activated and maintained. Thermal infrared imaging data from 14 systemic sclerosis subjects (SSc), 14 PRP, and 16 healthy control subjects (HCS) were processed. HCS presented the fastest active recovery, with the highest gain. PRP presented the slowest and weakest recovery, mostly due to passive heat exchange with the environment. SSc presented an intermediate behavior, with the longest delay of response onset. The estimated model parameters elucidated the level of functional impairment expressed in the various forms of this disease.

[Systemic sclerosis]

Systemic sclerosis (SSc; syn. systemic scleroderma) is a rare autoimmune disorder with characteristic cutaneous manifestations. Prevalence in women is fivefold higher than in men. The course of the disease is slowly progressive with a variable degree of internal organ involvement due to fibrosis and obliteration of small vessels. The diffuse form shows more frequent and severe organ manifestations compared to the limited form. Increased mortality is particularly related to a cardiopulmonary involvement leading to a 5-year survival of around 75%. Treatment indications are dependent on the severity of the disease. In the acute state, immunosuppressive agents are needed in case of significant organ involvement. Vasodilative drugs are often used for the symptomatic treatment of Raynaud's phenomenon.

Lipid peroxidation and trace elements in systemic sclerosis

Oxidative stress appears to be important in the causation and perpetuation of tissue injury and fibrosis in systemic sclerosis or scleroderma (SSc). We conducted a case-control study to assess lipid peroxidation levels as determined by measuring fasting plasma malondialdehyde (MDA) and serum levels of the trace elements selenium, iron, zinc and copper in SSc. Plasma MDA levels were almost tenfold higher in patients than in controls (p=0.00007), and an inverse relationship between MDA levels and disease duration (r=-0.52, p=0.044) was observed. Selenium levels were lower in patients than in controls (p=0.012). Within the patient cohort, copper correlated inversely with the total skin score (r=-0.52, p=0.03). Our findings provide further evidence that lipid peroxidation is increased and antioxidant capacity is reduced in SSc. The gradual decline in MDA levels with time suggests that antioxidant therapy, if to be useful in SSc, is most likely to be effective early in the course of the disease.

Oxygen free radical scavenger enzyme polymorphisms in systemic sclerosis

We performed a case-control study of polymorphisms of glutathione S-transferase (GST) isoenzymes and manganese superoxide dismutase (MnSOD) in black South Africans with systemic sclerosis (SSc). The frequency of the GSTM1*B phenotype was significantly decreased in the overall SSc group compared with controls (OR=0.19, p(corr)<.05), implying a possible protective effect against development of the disease. There was also a trend toward increased MnSODAla allele and phenotype frequencies in the diffuse cutaneous SSc subset compared with controls (OR=2.11 and 3.15, respectively, p(corr)<.1). Our findings provide new data on the distribution of GST and MnSOD polymorphisms in healthy Africans and further evidence that genetic factors may have a contributory role to play in predisposing to oxidative stress in SSc.

Visualization and functional consequence of pulmonary vascular impairment in patients with rheumatic diseases

STUDY OBJECTIVES

Systemic rheumatic diseases impair the vasculature in lungs. The aim of this study was to visualize vascular impairment and determine its consequence on lung function.

PATIENTS AND MEASUREMENTS

Seventy-two patients with rheumatic diseases were evaluated by pulmonary function tests, ventilation-perfusion scintigraphy, and thermography of the hands. The ventilation-perfusion mismatch of the lungs was visualized and quantified by calculating the ventilation-perfusion ratio (/) at each pixel. The microvascular impairment in fingers was assessed by the temperature difference between the nail fold and the dorsal hand.

RESULTS

Patients with rheumatic diseases exhibited an increased / that distributed at the periphery of the lungs. The diffusing capacity of the lung for carbon monoxide (DLCO) decreased (mean [+/- SD], 76.4 +/- 27.4% of predicted) relative to the vital capacity (VC) [mean, 88.4 +/- 21.8% of predicted; p < 0.01] regardless of the presence or absence of interstitial lung disease (ILD). The distal-dorsal temperature difference showed colder fingers in patients with Raynaud phenomenon (mean temperature, - 0.6 +/- 2.1 degrees C) than in those without it (mean temperature, 0.3 +/- 1.5 degrees C) and significantly correlated with the ventilation-perfusion mismatch of the lungs both in patients with ILD (p = 0.04) and in those without ILD (p = 0.02). The ventilation-perfusion mismatch of the lungs significantly correlated with the relative reduction in DLCO evaluated by the percent DLCO/percent VC ratio both in patients with ILD (p < 0.01) and in those without ILD (p = 0.02).

CONCLUSIONS

These results suggest that the periphery-distributed microvascular impairment in the lungs leads to ventilation-perfusion mismatch that functionally causes a relative reduction in DLCO in patients with rheumatic diseases. The reduction in DLCO relative to VC represents the vascular impairment in the lungs both in patients with ILD and in those without.

Epidemiology and pathogenesis of scleroderma

Scleroderma is a heterogenous connective tissue disorder characterized by fibrosis of the skin, with or without internal organ involvement. The aetiology of scleroderma may involve both environmental and genetic factors. Abnormalities involving the immune system, vascular tissue and extracellular matrix have been demonstrated. Recent research has focused on microchimerism as a risk factor for the development of scleroderma. This article reviews the epidemiology and pathogenesis of this disorder.

Endothelial dysfunction in murine model of systemic sclerosis: tight-skin mice 1

We conducted this study to analyze endothelial cell function within intact thoracic aorta of the systemic sclerosis murine model, the heterozygous tight-skin mice 1: (i) assessing the distribution and activation intensity of endothelial cells, responsive to endothelium-dependent vasodilators (acetylcholine, adenosine triphosphate, bradykinin, and substance P) and Iloprost, using laser line confocal microscopy in combination with two Ca2+ fluorescent dyes; (ii) evaluating en-dothelium-dependent vasodilator- and Iloprostinduced relaxation, using isometric tension measurement; and (iii) investigating the role of nitric oxide in mediating relaxation to acetylcholine and adenosine triphosphate. The number of activated endothelial cells was significantly lower in heterozygous tight-skin mice 1, compared with controls, for adenosine triphosphate and Iloprost. Maximal increase of Ca2+ fluorescence intensity ratio in activated endothelial cells was decreased for adenosine triphosphate, bradykinin, and Iloprost, in heterozygous tight-skin mice 1. Adenosine triphosphate- and Iloprost-mediated aortic relaxation was further impaired in heterozygous tight-skin mice 1. Finally, aortic relaxation to acetylcholine and adenosine triphosphate was markedly decreased by nitric oxide synthase inhibitor in heterozygous tight-skin mice 1. This study suggests that endothelial cell receptors for endothelium-dependent vasodilators and Iloprost may not be homogeneously distributed or continuously expressed in thoracic aorta of heterozygous tight-skin mice 1, resulting in endothelium-dependent vasodilatation dysfunction. Moreover, because endothelium-dependent relaxation was highly dependent on nitric oxide release in heterozygous tight-skin mice 1, endothelium-dependent relaxation may differ from that of controls by increased production of nitric oxide. In turn, in heterozygous tight-skin mice 1, the resulting elevated nitric oxide levels may contribute to nitric oxide-mediated free radical endothelial cytotoxicity, although endothelium impairment may be related to other factors, particularly: Fbn-1 gene mutation and transforming growth factor-beta.

Raynaud&#x0027;s phenomenon: Infrared functional imaging applied to diagnosis and drug effects

A non-invasive, innovative approach to the study of Raynaud&#x0027;s Phenomenon is proposed. A group of patients, with respect of a control group, underwent a simultaneous assessment of thermal properties of all ten fingers using infrared functional imaging (IRFI). The assessment highlighted a quite different behaviour between patients with Primary- (PRP) and those with scleroderma - Raynaud&#x0027;s Phenomenon (SSc) and, compared with other existing techniques, seems to be an objective and effective tool to discriminate between PRP and RP secondary to SSc. 18 healthy volunteers (Norm), 20 Primary Raynaud&#x0027;s Phenomenon (PRP) and 20 Secondary Scleroderma (SSc) patients were studied subsequently to clinical evaluation and nail fold capillaroscopy. High-resolution infrared imaging of finger re-warming processes, immediately after a 2 min cold stress, allowed to identify objective parameters. Temperature integral Q (the temperature evaluation of the area under the time-temperature curve along the re-warming period) provided particularly effective figures in describing thermal properties of the fingers. Grand average Q values were (383.4 &#x2213; 12.5) &#x00B0;C×min, (502.9 &#x00B1; 88.1) &#x00B0;C×min and (1022.0 &#x00B1; 110.2) &#x00B0;C×min for the PRP, SSc and Normal groups, respectively. Separate evaluation of the temperature integral for each finger leads to very similar results for the fingers of all the PRP patients; a different thermoregulatory response was observed in SSc patients. The sensitivity of the method in order to distinguish healthy from ill fingers was 100&#x0025;. The specificity in distinguishing SSc from PRP was 95&#x0025;. In addition, IRFI parameters provided a better understanding of the impaired control of the finger&#x0027;s temperature in PRP and SSc with respect to the Normal group. This pilot study also applied IRFI for the measurement of drug effects in patients with Raynaud&#x0027;s Phenomenon. Sixteen out of twenty SSc patients were tested in a single 1-hour session of N-acetylcysteine infusion. IRFI clearly documented a significant increase of face and hands temperature during the drug administration. The grand average value of the finger&#x0027;s temperature after the 1 hour NAC administration was (29.6 &#x00B1; 3.7) &#x00B0;C, while its value before was (27.9 &#x00B1; 3.7) &#x00B0;C (p&#x003C;0.001). N-acetylcysteine seems to act as a vasodilator in patients with Raynaud&#x0027;s phenomenon secondary to systemic sclerosis (scleroderma).

Differential expression of nitric oxide by dermal microvascular endothelial cells from patients with scleroderma

Vascular abnormalities in scleroderma are fundamental to the pathogenesis of this disease. The objective of this study was to characterize dermal microvascular endothelial cells (DMEC) isolated from scleroderma patients with respect to growth and expression of the constitutive form of endothelial nitric oxide synthase (eNOS). DMEC from patients with both systemic sclerosis (SSc) and localized scleroderma (Loc Scl) contained small intact microvascular structures in contrast to single cell isolations obtained from control skin. Immunoaffinity selection on anti-PECAM-1 beads yielded pure populations of DMEC expressing normal markers. While the morphology and initial growth of SSc DMEC closely paralleled control cells, the growth of SSc DMEC decreased with time in culture (doubling time of 3 days vs. 5 days). Expression of ecNOS mRNA was reduced in both Loc Scl and SSc as shown by semi-quantitative RT-PCR (p < 0.001). Western blots showed variable but generally lower ecNOS protein levels and decreased levels of nitrogen oxides in media were found from both SSc and Loc Scl relative to control cells. The results indicate an intrinsic defect in the mechanism of nitric oxide production in DMEC isolated from scleroderma patients and suggest its possible involvement in the pathophysiology of scleroderma.

Measurement of soluble adhesion molecules in primary Raynaud's phenomenon and in Raynaud's phenomenon secondary to connective tissue diseases

Adhesion molecules play a role in the inflammation and pathogenesis of vascular diseases. In 13 patients with primary Raynaud's phenomenon, 19 with Raynaud's phenomenon associated with connective tissue disease, and 16 control subjects, we measured plasma levels of soluble forms of intercellular adhesion molecule-1, vascular cell adhesion molecule-1, E-selectin, and von Willebrand factor. Patients with secondary Raynaud's phenomenon had plasma levels of soluble forms of intercellular adhesion molecule- 1, vascular cell adhesion molecule-1, E-selectin, and von Willebrand factor which were significantly higher than in those with primary Raynaud's phenomenon and controls, while no difference was observed between patients with primary Raynaud's phenomenon and controls. Within the group with secondary Raynaud's phenomenon, the strongest correlations were between soluble forms of intercellular adhesion molecule-1 and both E-selectin, (r=0.67, P<0.001) and von Willebrand factor (r=0.58, P<0.01). In none of the three groups were the levels of soluble adhesion molecules and von Willebrand factor changed by exposure of hands to cold, although all patients had a definite vasospasm. In conclusion, this study indicates that primary Raynaud's phenomenon is not associated with elevation of soluble adhesion molecules and von Willebrand factor. Prospective studies are now required to investigate the role of these molecules as predictors of secondary diseases.

Monocytes of patients wiht systemic sclerosis (scleroderma spontaneously release in vitro increased amounts of superoxide anion

It has been suggested that toxic oxygen free radicals can be involved in the pathogenesis of systemic sclerosis (scleroderma) (SSc). Because the cells that contribute to the generation of free radicals are not known, our aim was (i) to evaluate the ability of unmanipulated and phorbol 12-myristate 13-acetate-stimulated monocytes and polymorphonucleate neutrophils of SSc patients to generate superoxide anion (O2*-); and (ii) to investigate whether the O2*- produced by these cells involved the activation of nicotinamide-adenine dinucleotide diphosphate oxidase biochemical pathway. Employing the superoxide dismutase-inhibitable reduction of cytochrome c to evaluate the generation of O2*-, unmanipulated monocytes of SSc patients generated more O2*- than primary Raynaud's phenomenon patients and normal control monocytes (p = 0.0001), and the release was higher in patients with diffuse cutaneous involvement and 5 y or less disease duration (p = 0.02). The involvement of nicotinamide-adenine dinucleotide diphosphate oxidase in the enhanced 02*- production was demonstrated by the finding that the cytosolic components of the enzyme, p47phox and p67phox, were both translocated to the plasma membrane of enriched but otherwise unmanipulated monocytes of SSc patients. The involvement of mitochondrial oxidases was excluded by the lack of inhibition of O2*- production when monocytes were incubated in the presence of rotenone, a mitochondrial oxidase inhibitor. Upon stimulation with phorbol 12-myristate 13-acetate, monocytes of SSc patients produced more O2*- than controls. In SSc patients untreated polymorphonucleate neutrophils generated significantly less O2*- than monocytes (p = 0.0001) and only slightly more than polymorphonucleate neutrophils of primary Raynaud's phenomenon patients and normal controls (p = 0.03). In conclusion, we demonstrate that in patients with scleroderma, unmanipulated and phorbol 12-myristate 13-acetate-stimulated monocytes release in vitro increased amounts of superoxide anion through the activation of nicotinamide-adenine dinucleotide diphosphate oxidase and, thus, contribute to the oxidative stress found in this disease.

Vascular abnormalities in scleroderma

Vascular abnormalities represent a fundamental event in the pathogenesis of systemic sclerosis. This review focuses on key observations that support this view and builds a framework with which to clarify our understanding of how endothelial cell damage may trigger a self-fueling process ending in pathological tissue fibrosis in those susceptible to scleroderma. The studies reviewed in this article pertain to systemic sclerosis patients.

The occurrence of Raynaud's phenomenon in a general population: the Framingham Study

The prevalence and predisposing conditions for primary and secondary Raynaud's phenomenon (RP) were examined in The Framingham Study based on 16 years of follow-up of a cohort of 4182 men and women. The association with atypical chest pain and migraine headache was also investigated. Over the 16 years of follow-up there were 130 men and 171 women who developed primary RP. The prevalence in women (9.6%) was somewhat higher than in men (8.1%) and 81.4% of the RP was primary. Secondary RP was equally prevalent in men (18.6%) and women (19.7%). The most common causes of secondary RP were beta-blocker use (34.2%), carpal tunnel syndrome (10.5%) and rheumatoid arthritis (7.2%). Primary RP cases differed from noncases by having lower systolic blood pressure (p < or = 0.001) and diastolic blood pressure (p < 0.0001), and more coronary disease (p = 0.009), smoking (p < or = 0.01) and higher blood sugars (p < or = 0.009). Atypical chest pain was present more often than noted previously in The Framingham Study general population survey, and was equally prevalent in primary and secondary RP and in the two sexes. Associated migraine was more prevalent in women (14.4%) than men (5.0%). Vibrating tool use with associated RP occurred in 14.6%.

Scleroderma autoantigens are uniquely fragmented by metal-catalyzed oxidation reactions: implications for pathogenesis

The observation that revelation of immunocryptic epitopes in self antigens may initiate the autoimmune response has prompted the search for processes which induce novel fragmentation of autoantigens as potential initiators of autoimmunity. The reversible ischemia reperfusion which characterizes scleroderma has focused attention on reactive oxygen species as molecules which might induce autoantigen fragmentation. We demonstrate that several of the autoantigens targeted in diffuse scleroderma are uniquely susceptible to cleavage by reactive oxygen species, in a metal-dependent manner. Multiple features of the fragmentation reaction and its inhibition indicate that these autoantigens possess metal-binding sites, which focus metal-catalyzed oxidation reactions (and consequent fragmentation) to specific regions of the antigens. These data suggest that the autoantibody response in scleroderma is the immune marker of unique protein fragmentation, induced by ischemia reperfusion in the presence of appropriate metals, and focus attention on abnormal metal status as a potential pathogenic principle in this disease.

Left ventricular myocardial perfusion and function in systemic sclerosis before and after diltiazem treatment

To examine left ventricular (LV) myocardial perfusion and function, in systemic sclerosis. Myocardial perfusion was assessed at rest, during cold exposure, and at peak exercise in 10 patients with systemic sclerosis. Seven of the 10 patients were examined with Doppler echocardiography; before and after long-term diltiazem treatment. Compared with average resting values, isotope uptake was increased by 48% after exercise, compared with cold exposure the exercise value was increased by 35%. After 11 months of diltiazem treatment there was no change in myocardial uptake, compared with respective values before treatment. Doppler echocardiography showed an increase in LV end-diastolic diameter, fractional shortening, and left ventricular outflow tract velocity, after treatment. This indicates that long-term diltiazem treatment does not increase myocardial perfusion at rest, post-exercise, or during cold exposure. On the other hand diltiazem treatment may improve left ventricular performance.

Increased prevalence of symptomatic macrovascular disease in systemic sclerosis

OBJECTIVES

To determine the prevalence of symptomatic macrovascular disease, as defined by the World Health Organisation questionnaire for intermittent claudication, in patients with systemic sclerosis (SSc), and to compare the prevalence in this population with a cross sectional population study group reported in the Edinburgh Artery Study (EAS).

METHODS

A group of 53 patients with a diagnosis of limited or diffuse systemic sclerosis were identified from our register. They were asked to complete the WHO questionnaire to establish the presence or absence of intermittent claudication. In addition, each patient's case notes were reviewed to establish the existence of definite peripheral vascular disease and to determine their risk factor profile.

RESULTS

Forty six patients responded to the questionnaire, giving a response rate of 87%. Intermittent claudication was found in 10 SSc patients (21.7%) according to the questionnaire (two with diffuse and eight with limited SSc), compared with a prevalence rate of 4.6% for claudication in the EAS. Three SSc patients experienced clinical events attributable to occlusion of a major artery proven on angiography. Four patients had hypertension, there were three current and four ex-smokers, and two had increased total cholesterol. None of these patients had diabetes.

CONCLUSIONS

This study demonstrated a greater prevalence of macrovascular disease in patients with SSc than had been found in a neighbouring population.

Immunocytochemical characterization of human NOR-90 (upstream binding factor) and associated antigens reactive with autoimmune sera. Two MR forms of NOR-90/hUBF autoantigens

The 90-kDa nucleolus organizer region autoantigen (NOR-90) was previously shown to be identical to the human upstream binding factor (hUBF) and composed of two Mr forms. In this study, thirteen human anti-NOR-90/hUBF autoimmune sera were used to further characterize NOR-90/hUBF and its associated autoantigens. Nucleolar and nucleoplasmic staining of interphase cells and NOR staining in mitosis were observed with all sera by immunofluorescence. All sera showed equal reactivity with both high and low Mr forms in Western blotting and immunoprecipitation, suggesting that the cellular content and distribution for both Mr forms were approximately equal. Using extracts of [35S]methionine- and [32P]orthophosphate-labeled cells, phosphorylated and nonphosphorylated NOR-90/hUBF were identified for both Mr forms and these two populations were recognized by human autoantibodies. In immunoprecipitation analyses, the nonphosphorylated population was readily extracted while the phosphorylated population was tightly bound. Clinical data were available for 8 patients in whom anti-NOR-90/hUBF autoantibodies were present. They had diverse diagnoses including SLE, rheumatoid arthritis and malignancies. Although only one patient was diagnosed as scleroderma, Raynaud's phenomenon was observed in 4 of the 8 patients. Interestingly, one NOR-90/hUBF serum was shown to contain additional antibodies to RNA polymerases I and II.

Systemic sclerosis

Systemic sclerosis affects the connective tissue of various organs. It is characterized by alteration of the microvasculature with a dense inflammatory cellular infiltrate, followed by massive deposition of collagen. This review discusses diagnostic criteria, clinical subsets, survival data, clinical evaluation, epidemiology, pathogenesis, immunobiology, genetics, and therapy for systemic sclerosis in adults. Because the diagnosis of systemic sclerosis is most dependent on its cutaneous involvement, knowledge of this is essential in the evaluation and management of patients with this disorder.