The impact of cardiovascular co-morbidities and duration of diabetes on the association between microvascular function and glycaemic control.

BACKGROUND: Good glycaemic control in type 2 diabetes (T2DM) protects the microcirculation. Current guidelines suggest glycaemic targets be relaxed in advanced diabetes. We explored whether disease duration or pre-existing macrovascular complications attenuated the association between hyperglycaemia and microvascular function. METHODS: 743 participants with T2DM (n = 222), cardiovascular disease (CVD = 183), both (n = 177) or neither (controls = 161) from two centres in the UK, underwent standard clinical measures and endothelial dependent (ACh) and independent (SNP) microvascular function assessment using laser Doppler imaging. RESULTS: People with T2DM and CVD had attenuated ACh and SNP responses compared to controls. This was additive in those with both (ANOVA p < 0.001). In regression models, cardiovascular risk factors accounted for attenuated ACh and SNP responses in CVD, whereas HbA1c accounted for the effects of T2DM. HbA1c was associated with ACh and SNP response after adjustment for cardiovascular risk factors (adjusted standardised beta (ß) -0.096, p = <0.008 and -0.135, p < 0.001, respectively). Pre-existing CVD did not modify this association (ß -0.099; p = 0.006 and -0.138; p < 0.001, respectively). Duration of diabetes accounted for the association between HbA1c and ACh (ß -0.043; p = 0.3), but not between HbA1c and SNP (ß -0.105; p = 0.02). CONCLUSIONS: In those with T2DM and CVD, good glycaemic control is still associated with better microvascular function, whereas in those with prolonged disease this association is lost. This suggests duration of diabetes may be a better surrogate for "advanced disease" than concomitant CVD, although this requires prospective validation.

Effect of intermittent vitamin D3 on vascular function and symptoms in chronic fatigue syndrome--a randomised controlled trial.

BACKGROUND AND AIMS: Low 25-hydroxyvitamin D levels are common in patients with chronic fatigue syndrome; such patients also manifest impaired vascular health. We tested whether high-dose intermittent oral vitamin D therapy improved markers of vascular health and fatigue in patients with chronic fatigue syndrome. METHODS AND RESULTS: Parallel-group, double-blind, randomised placebo-controlled trial. Patients with chronic fatigue syndrome according to the Fukuda (1994) and Canadian (2003) criteria were randomised to receive 100,000 units oral vitamin D3 or matching placebo every 2 months for 6 months. The primary outcome was arterial stiffness measured using carotid-femoral pulse wave velocity at 6 months. Secondary outcomes included flow-mediated dilatation of the brachial artery, blood pressure, cholesterol, insulin resistance, markers of inflammation and oxidative stress, and the Piper Fatigue scale. As many as 50 participants were randomised; mean age 49 (SD 13) years, mean baseline pulse wave velocity 7.8 m/s (SD 2.3), mean baseline office blood pressure 128/78 (18/12) mmHg and mean baseline 25-hydroxyvitamin D level 46 (18) nmol/L. 25-hydroxyvitamin D levels increased by 22 nmol/L at 6 months in the treatment group relative to placebo. There was no effect of treatment on pulse wave velocity at 6 months (adjusted treatment effect 0.0 m/s; 95% CI -0.6 to 0.6; p = 0.93). No improvement was seen in other vascular and metabolic outcomes, or in the Piper Fatigue scale at 6 months (adjusted treatment effect 0.2 points; 95% CI -0.8 to 1.2; p = 0.73). CONCLUSION: High-dose oral vitamin D3 did not improve markers of vascular health or fatigue in patients with chronic fatigue syndrome. TRIAL REGISTRATION: www.controlled-trials.com, ISRCTN59927814.

Technical assessment of whole body angiography and cardiac function within a single MRI examination.

AIM: To evaluate a combined protocol for simultaneous cardiac MRI (CMR) and contrast-enhanced (CE) whole-body MR angiography (WB-MRA) techniques within a single examination. MATERIALS AND METHODS: Asymptomatic volunteers (n = 48) with low-moderate risk of cardiovascular disease (CVD) were recruited. The protocol was divided into four sections: (1) CMR of left ventricle (LV) structure and function; (2) CE-MRA of the head, neck, and thorax followed by the distal lower limbs; (3) CMR LV "late gadolinium enhancement" assessment; and (4) CE-MRA of the abdomen and pelvis followed by the proximal lower limbs. Multiple observers undertook the image analysis. RESULTS: For CMR, the mean ejection fraction (EF) was 67.3 ± 4.8% and mean left ventricular mass (LVM) was 100.3 ± 22.8 g. The intra-observer repeatability for EF ranged from 2.1-4.7% and from 9-12 g for LVM. Interobserver repeatability was 8.1% for EF and 19.1 g for LVM. No LV delayed myocardial enhancement was observed. For WB-MRA, some degree of luminal narrowing or stenosis was seen at 3.6% of the vessel segments (involving n = 29 of 48 volunteers) and interobserver radiological opinion was consistent in 96.7% of 1488 vessel segments assessed. CONCLUSION: Combined assessment of WB-MRA and CMR can be undertaken within a single examination on a clinical MRI system. The associated analysis techniques are repeatable and may be suitable for larger-scale cardiovascular MRI studies.

In vivo noninvasive measurement of skin autofluorescence biomarkers relate to cardiovascular disease in mice.

BACKGROUND AND OBJECTIVE: The formation of reactive oxygen species (ROS) is associated with cardiovascular disease (CVD). High dietary cholesterol can significantly alter the delicate balance between pro-oxidation and antioxidant defences leading to reactive oxygen species formation in the vasculature, without significant structural changes in tissue composition. We aimed to establish a methodology for the noninvasive assessment of skin fluorescent biomarkers in mice. MATERIALS AND METHODS: C57/black/6 wild-type (WT; n = 25) male mice were subdivided to receive normal rodent chow (n = 11) or a high cholesterol diet (2% cholesterol; n = 14) for 20 weeks. Skin autofluorescence measurements were made on the backs of anaesthetized (1.5-2% isoflurane in oxygen) mice. A laser probe was used to make simultaneous measurements of: collagen, elastin, nicotinamide pyridoxine, flavins, lipofuscin and ß-carotene. Results are expressed as group mean in arbitrary units (AU) ± standard error (SE). Hearts were excised and weighed (mg); cardiac hypertrophy was measured by ratio [heart weight (mg)/bodyweight (g) ± SE]. Student's t-test was used for statistical significance analysis (p ≤ 0.05). RESULTS: There were no significant differences between cholesterol- and chow-fed animals for collagen (34 ± 5AU vs. chow 34 ± 4 AU, p = 0.51) and elastin (66 ± 6 AU vs. chow 82 ± 7 AU, p = 0.11). Significant differences were evident for nicotinamide adenine dinucleotide (92 ± 7 AU vs. chow 118 ± 7 AU, p = 0.01), pyridoxine (56 ± 4 AU vs. chow 73 ± 4 AU, p = 0.01), flavins (44 ± 3 AU vs. chow 57 ± 4 AU, p = 0.01), lipofuscin (35 ± 3 AU vs. chow 46 ± 3 AU, p = 0.01) and ß-carotene (19 ± 2 AU vs. chow 25 ± 2 AU, p = 0.01). Cholesterol-fed animals had significantly heavier hearts (7 ± 0.3 ratio vs. chow 5 ± 0.1 ratio, p = 0.001). CONCLUSION: Cholesterol feeding induced cardiovascular disease as noted by cardiac hypertrophy in wild-type mice. A reduction was observed in pyridoxine, nicotinamide adenine dinucleotide, flavins, lipofuscin and ß-carotene, which are established risk factors for cardiovascular disease. We report no significant changes in structural proteins collagen and elastin, suggesting no generalized tissue restructuring, which might otherwise explain the observed pathological differences.

Medical management of critical limb ischaemia: where do we stand today?

Critical limb ischaemia (CLI) is a severe form of peripheral arterial disease (PAD). CLI often causes disabling symptoms of pain and can lead to loss of the affected limb. It is also associated with increased risk of myocardial infarction, stroke and death from cardiovascular disease. The aims of management in patients with CLI are to relieve ischaemic pain, heal ulcers, prevent limb loss, improve function and quality of life and prolong survival. Here, current evidence regarding the medical management of CLI is reviewed. Cardiovascular risk factors should be assessed in all patients with CLI; smoking cessation and treatment of hypertension, hyperlipidaemia and diabetes all reduce the mortality rate in those with PAD. Antiplatelet agents (either aspirin or clopidogrel) are recommended to reduce both the incidence of cardiovascular events and risk of arterial occlusion. By contrast, routine use of anticoagulation (either warfarin or heparin) is not recommended. Treatment of the limbs themselves is often more challenging. Prostanoids may have some efficacy for treating rest pain and for ulcer healing, and iloprost shows favourable results in reducing the risk of major amputations, but long-term follow-up data regarding disease progression are lacking. There is insufficient evidence to support the use of naftidrofuryl or cilostazol, and pentoxifylline is not beneficial. Furthermore, there is no evidence of proven benefit of hyperbaric oxygen. A number of angiogenic growth factors have been studied in Phase I studies and randomized controlled trials (RCTs). They appear to be safe, but efficacy results have been mixed. Treatment with stem cells also shows some potential from early trials, but further larger RCTs are needed to demonstrate clear benefit. Thrombolysis may be an alternative for patients who develop acute limb ischaemia and are unsuitable for surgical intervention. However, newer endovascular techniques are likely to have a greater role in the future.

Rosuvastatin might have an effect on C-reactive protein but not on rheumatoid disease activity: Tayside randomized controlled study.

The aim of this study was to study the effects of rosuvastatin in patients with rheumatoid arthritis (RA) looking at the C-reactive protein (CRP), interleukin-6 (IL-6) and joint disease activity. Fifty RA patients were randomized in a double-blind placebo-controlled trial to receive either 10 mg of rosuvastatin or placebo as an adjunct to existing disease-modifying antirheumatic therapy. Patients were followed up for a six-month period. Measurements were done at baseline and six months. CRP and IL-6 were measured in the blood. RA disease activity was measured using disease activity score based on 28 joint counts (DAS 28). When analysing from baseline to six months there was no difference between the rosuvastatin and placebo groups in rheumatoid disease activity (-0.01; standard deviation [SD], 1.08; and +0.18; SD, 0.95; respectively; P value 0.509). There was a trend towards improvement in CRP in the rosuvastatin group (-3.23; SD, 18.18) compared with the placebo group (+17.43; SD, 38.03); P value, 0.161. IL-6 showed a trend towards worsening in the rosuvastatin group (+0.15; SD, 1.09) compared with placebo (-0.73; SD, 1.4); P value, 0.054. These data show that rosuvastatin with might decrease the CRP independent to IL-6 in patients with RA but does not improve the overall rheumatoid disease activity.

A novel approach to measuring skin elasticity in systemic sclerosis: results from a pilot study.

OBJECTIVES: Systemic sclerosis (SSc) is characterized by progressive fibrosis of various organs, and causes hard, tethered, and inelastic skin. The modified Rodnan score is used to quantify skin involvement, but this method is subjective and user dependent. The aim of this study was to test the ability of a new skin torsion device to measure skin elasticity in patients with SSc. METHODS: The study included 16 female SSc patients and 58 healthy controls. Skin elasticity was assessed on the forearms and backs of the hands using a new hand-held device that gently rotates the skin for 15 s to a maximum of 40 deg, and measures the speed of rotation and the angle of rotation at 15 s. Total and localized modified Rodnan scores were also documented. RESULTS: Measurements produced by the skin torsion device had good intra-subject reproducibility, particularly in the control group. The SSc patients had significantly lower skin elasticity than an age-matched subgroup of control subjects, as determined by the median speed of rotation of the device in the hands (1.91 vs. 2.60 deg/s, p < 0.0001) and forearms (1.84 vs. 2.46 deg/s, p < 0.0001), and the rotation at 15 s in the hands (28.6 vs. 39.0 deg, p < 0.0001) and forearms (27.6 vs. 36.9 deg, p < 0.0001). The presence of SSc disease was the only independent predictor of skin elasticity. CONCLUSIONS: This pilot study has shown the potential value of a new skin torsion device to assess skin involvement in patients with SSc.

The next 10 years in the management of peripheral artery disease: perspectives from the 'PAD 2009' Conference.

OBJECTIVES: To briefly inform on the conclusions from a conference on the next 10 years in the management of peripheral artery disease (PAD). DESIGN OF THE CONFERENCE: International participation, invited presentations and open discussion were based on the following issues: Why is PAD under-recognised? Health economic impact of PAD; funding of PAD research; changes of treatment options? Aspects on clinical trials and regulatory views; and the role of guidelines. RESULTS AND CONCLUSIONS: A relative lack of knowledge about cardiovascular risk and optimal management of PAD patients exists not only among the public, but also in parts of the health-care system. Specialists are required to act for improved information. More specific PAD research is needed for risk management and to apply the best possible evaluation of evidence for treatment strategies. Better strategies for funding are required based on, for example, public/private initiatives. The proportion of endovascular treatments is steadily increasing, more frequently based on observational studies than on randomised controlled trials. The role of guidelines is therefore important to guide the profession in the assessment of most relevant treatment.

Plasma IL-6, its soluble receptors and F2-isoprostanes at rest and during exercise in chronic fatigue syndrome.

The aim of the current study was to investigate the levels of interleukin-6 (IL-6), its soluble receptors (sIL-6R and sgp130) and F(2)-isoprostanes, at rest and during exercise, in patients with chronic fatigue syndrome (CFS). Six male CFS patients and six healthy controls performed an incremental exercise test to exhaustion and a submaximal exercise bout to exhaustion. Blood samples taken in the submaximal test at rest, immediately post-exercise and 24 h post-exercise were analyzed for IL-6, sIL-6R, sgp130 and F(2)-isoprostanes. A further 33 CFS and 33 healthy control participants gave a resting blood sample for IL-6 and sIL-6R measurement. During the incremental exercise test only power output at the lactate threshold was lower (P<0.05) in the CFS group. F(2)-isoprostanes were higher (P<0.05) in CFS patients at rest and this difference persisted immediately and 24 h post-exercise. The exercise study found no differences in IL-6, sIL-6R or sgp130 at any time point between groups. In the larger resting group, there were no differences in IL-6 and sIL-6R between CFS and control groups. This investigation has demonstrated that patients with CFS do not have altered plasma levels of IL-6, sIL-6R or sgp130 either at rest or following exercise. F(2)-isoprostanes, however, were consistently higher in CFS patients.

Macrovascular disease in systemic sclerosis: the tip of an iceberg?

This mini review evaluates mortality in SSc and provides a literature review concluding that premature death does occur in this population. However, there has been a changing spectrum of cause of death over the past three decades, with interstitial lung disease now being the commonest cause of SSc-related mortality. Cardiovascular (CV) mortality and events also contribute to the premature mortality seen in these patients, and this contention is supported by epidemiological studies, and further underpinned by a plethora of increased biomarkers for CV disease and events. Thus, macrovascular disease does occur in these patients, and is likely to contribute to mortality. It remains to be seen whether addressing conventional risk factors will attenuate CV disease in this population.

C-reactive protein: the underlying cause of microvascular dysfunction in rheumatoid arthritis.

OBJECTIVE: RA is a chronic autoimmune inflammatory condition associated with increased cardiovascular morbidity and mortality. Endothelial dysfunction, a marker of early atherosclerotic disease, occurs in some inflammatory diseases but this relationship has not been previously explored within the microvasculature of patients with RA. We therefore assessed forearm microvascular endothelial function in patients with RA and determined its relationship to RA disease activity and inflammation. METHODS: A total of 128 RA patients with no previous history of cardiovascular disease were evaluated. Endothelium-dependent and -independent forearm skin microvascular function was measured using laser Doppler imaging after iontophoretic delivery of acetylcholine (ACh) and sodium nitroprusside (SNP), respectively. Parameters of RA disease activity and inflammation were also checked. RESULTS: There was a significant negative correlation between the level of inflammation measured by log(10)CRP and maximum vasodilatation measured by peak ACh response (r(2) = -0.209, P = 0.018, Pearson correlation test). In a multiple regression model, age (beta = -0.449, P < 0.0001) and log(10)CRP (beta = -0.193, P = 0.026) were independently negatively associated with ACh responses. When RA patients were sub-divided according to their systemic inflammatory status (CRP > 10 mg/l vs CRP

Cod liver oil (n-3 fatty acids) as an non-steroidal anti-inflammatory drug sparing agent in rheumatoid arthritis.

OBJECTIVES: Dose-dependant gastrointestinal and cardiovascular side-effects limit the use of NSAIDs in the management of RA. The n-3 essential fatty acids (EFAs) have previously demonstrated some anti-inflammatory and NSAID-sparing properties. The objective of this study was to determine whether cod liver oil supplementation helps reduce daily NSAID requirement of patients with RA. METHODS: Dual-centre, double-blind placebo-controlled randomized study of 9 months' duration. Ninety-seven patients with RA were randomized to take either 10 g of cod liver oil containing 2.2 g of n-3 EFAs or air-filled identical placebo capsules. Documentation of NSAID daily requirement, clinical and laboratory parameters of RA disease activity and safety checks were done at 0, 4, 12, 24 and 36 weeks. At 12 weeks, patients were instructed to gradually reduce, and if possible, stop their NSAID intake. Relative reduction of daily NSAID requirement by >30% after 9 months was the primary outcome measure. RESULTS: Fifty-eight patients (60%) completed the study. Out of 49 patients 19 (39%) in the cod liver oil group and out of 48 patients 5 (10%) in the placebo group were able to reduce their daily NSAID requirement by >30% (P = 0.002, chi-squared test). No differences between the groups were observed in the clinical parameters of RA disease activity or in the side-effects observed. CONCLUSIONS: This study suggests that cod liver oil supplements containing n-3 fatty acids can be used as NSAID-sparing agents in RA patients.

The adjuvant benefit of angioplasty in patients with mild to moderate intermittent claudication (MIMIC) managed by supervised exercise, smoking cessation advice and best medical therapy: results from two randomised trials for stenotic femoropopliteal and aortoiliac arterial disease.

BACKGROUND: Uncertainty exists on whether there is adjuvant benefit of percutaneous transluminal angioplasty (PTA) over supervised exercise and best medical therapy in the treatment of intermittent claudication. METHODS: Patients with symptoms of stable mild to moderate intermittent claudication (MIMIC) were randomised in two multi-centre trials, for femoropopliteal and aortoiliac arterial disease, to receive either PTA or no PTA against a background of supervised exercise and best medical therapy and followed up for 24 months. Initial claudication distance (ICD) and absolute walking distance (AWD) on treadmill were compared between randomised groups adjusting for the corresponding measure at baseline. Secondary outcomes included ankle-brachial pressure index (ABPI) and quality of life. FINDINGS: A total of 93 patients were randomised into the femoropopliteal trial (48 into PTA) and 34 into the aortoiliac trial (19 to PTA). The mean (standard deviation, SD) age was 66(9) years for the femoropopliteal trial (63% male) and 63(9) for the aortoiliac trial (65% male). At 24 months, there were significant improvements in both AWD and ICD in the PTA groups for both trials. The adjusted AWD was 38% greater in the PTA group for the femoropopliteal trial (95%; CI 1-90) (p=0.04) and 78% greater in the PTA group for the aortoiliac trial (95%; CI 0-216) (p=0.05). Further benefits were demonstrated for ABPI but not for quality of life. INTERPRETATION: PTA confers adjuvant benefit over supervised exercise and best medical therapy in terms of walking distances and ABPI 24 months after PTA in patients with stable mild to moderate intermittent claudication.

The inhibitory effects of local anaesthetics on the vascular flare responses to bradykinin and substance P in human skin.

Bradykinin and substance P are involved in inflammation and act through Gq-protein-coupled receptors. Local anaesthetics inhibit the signalling of these receptors and have potent anti-inflammatory actions. The aim of this study was to investigate the effects of local anaesthetics on the cutaneous flare responses to bradykinin and substance P. Skin blood flow responses to intradermal injections of bradykinin and substance P were assessed in the absence and presence of anaesthetic and analgesic concentrations of lidocaine, levobupivacaine and ropivacaine. All local anaesthetics significantly attenuated the vascular responses to bradykinin (p = 0.001) and substance P (p < 0.001). There were no differences in this effect between the different agents, but anaesthetic concentrations had a greater attenuating effect than analgesic concentrations on the substance P response (p < 0.001). Local anaesthetics may therefore be useful in the suppression of inflammation and the prevention of postoperative hyperalgesia.

Improvement in systemic endothelial condition following amputation in patients with critical limb ischemia.

AIM: Most patients with critical limb ischemia (CLI) have co-existing coronary heart disease, which is the main cause of their increased mortality. Peripheral ischemic tissue produces circulating toxic molecules, which may worsen endothelial function systemically and contribute to the general atherosclerotic process within the body. We looked at whether markers of endothelial function improve after amputation of the ischemic limb, when this potential source of toxins has been removed. METHODS: We measured blood levels of vascular endothelial growth factor (VEGF), homocysteine, endothelin-1, vascular cell adhesion molecule-1, E-selectin, thrombomodulin and von Willebrand factor (vWF) in 40 patients with CLI. We also assessed peripheral microvascular function in forearm skin by measuring responses to iontophoresis of acetylcholine and sodium nitroprusside. The measurements were repeated 6 months after amputation. RESULTS: We found abnormally high levels of endothelial products in the patients, and 6 months later VEGF and vWF had both reduced significantly from previous values (by 70% and 40%, respectively; P<0.01 in both cases). CONCLUSION: Improvements in these two markers after amputation are consistent with the hypothesis that peripheral ischemic tissue has a systemic effect on the vascular endothelium and may contribute to the progression of coronary heart disease in patients with CLI.

High-dose allopurinol improves endothelial function by profoundly reducing vascular oxidative stress and not by lowering uric acid.

BACKGROUND: Allopurinol has been shown to improve endothelial function in chronic heart failure. This study aimed to establish its mechanism of action and to construct a dose-response curve for the effect of allopurinol. METHODS AND RESULTS: Two randomized, placebo-controlled, double-blind, crossover studies were performed for 1 month on patients with New York Heart Association Class II-III chronic heart failure, comparing 300 mg allopurinol, 600 mg allopurinol, and placebo for the first study and 1000 mg probenecid versus placebo in the second study. Endothelial function was assessed by standard forearm venous occlusion plethysmography. Allopurinol 600 mg/d significantly increased forearm blood flow response to acetylcholine compared with both allopurinol 300 mg/d and placebo (% change in forearm blood flow [mean+/-SEM]: 240.31+/-38.19% versus 152.10+/-18.21% versus 73.96+/-10.29%, P<0.001). For similar levels of urate lowering, the uricosuric agent probenecid had no effect on endothelial function. Sodium nitroprusside response was unchanged by all treatments. Vitamin C and acetylcholine coinfusion data showed that 600 mg/d allopurinol completely abolished the oxidative stress that was sensitive to high-dose vitamin C. CONCLUSIONS: For the first time, we have shown that a steep dose-response relationship exists between allopurinol and its effect on endothelial function. We also showed that the mechanism of improvement in endothelial function with allopurinol lies in its ability to reduce vascular oxidative stress and not in urate reduction. The reduction in vascular oxidative stress was profound because high-dose allopurinol totally abolished the oxidative stress that was sensitive to the high-dose vitamin C that was used in this study.

Effects of poor glucose handling on arterial stiffness and left ventricular mass in normal children.

AIM: Cardiovascular risk factors can be present in children and young adults. We previously found abnormal microvascular function in children who had glucose intolerance and insulin resistance. The aim of the present study was to investigate whether they also have abnormalities in left ventricular mass (LVM) and arterial stiffness. METHODS: We measured heart dimensions and LVM using echocardiography, and arterial stiffness using pulse wave analysis in 23 children with good glucose handling (postfeeding glucose: 3.9 to 5 mmol/L) and 21 with poor glucose handling (7.7 to 11.4 mmol/L). RESULTS: The time to pulse reflection was slightly shorter in the poorer glucose handlers (mean+/-SD: 143+/-10 vs 153+/-20 ms, P=0.04), suggestive of increased arterial stiffness. Also in this group, there were significant relationships between intraventricular septal thickness, blood pressure and body mass index, but not in the normal glucose handlers. CONCLUSIONS: We have found that normal children who are in the lowest quintile of glucose tolerance in comparison with their peers are exhibiting the first signs of arterial stiffening. In addition, we have seen the beginnings of a relationship between blood pressure, body mass index and left ventricular enlargement in this group. While these changes may not yet be clinically significant, their emergence might be further evidence of early predisposition to cardiovascular disease.

Increased neutrophil apoptosis in chronic fatigue syndrome.

BACKGROUND/AIMS: Many patients with chronic fatigue syndrome (CFS) have symptoms that are consistent with an underlying viral or toxic illness. Because increased neutrophil apoptosis occurs in patients with infection, this study examined whether this phenomenon also occurs in patients with CFS. METHODS: Apoptosis was assessed in patients with CFS in conjunction with concentrations of the anti-inflammatory cytokine, transforming growth factor beta1 (TGFbeta1). RESULTS: The 47 patients with CFS had higher numbers of apoptotic neutrophils, lower numbers of viable neutrophils, increased annexin V binding, and increased expression of the death receptor, tumour necrosis factor receptor-I, on their neutrophils than did the 34 healthy controls. Patients with CFS also had raised concentrations of active TGFbeta1 (p < 0.005). CONCLUSIONS: These findings provide new evidence that patients with CFS have an underlying detectable abnormality in their immune cells.

Acetylcholine mediated vasodilatation in the microcirculation of patients with chronic fatigue syndrome.

The aetiology of chronic fatigue syndrome (CFS) remains controversial and a number of hypotheses have been put forward to explain it. Research into the condition is hindered by the considerable heterogeneity seen across patients but several reports have highlighted disturbances to cholinergic mechanisms in terms of central nervous system activity, neuromuscular function and autoantibodies to muscarinic cholinergic receptors. This paper examines an altogether separate function for acetylcholine and that is its role as an important and generalized vasodilator. Most diseases are accompanied by a blunted response to acetylcholine but the opposite is true for CFS. Such sensitivity is normally associated with physical training so the finding in CFS is anomalous and may well be relevant to vascular symptoms that characterise many patients. There are several mechanisms that might lead to ACh endothelial sensitivity in CFS patients and various experiments have been designed to unravel the enigma. These are reported here.

Vascular endothelial growth factor in patients with critical limb ischemia before and after amputation.

BACKGROUND: It is known that levels of vascular endothelial growth factor (VEGF) in biological fluids increase with inflammation and vascular proliferation. Theraputic angiogenesis by injection of VEGF or genes encoding for it may be a promising strategy for treatment of critical limb ischemia. However growth factors are also implicated in the development of vascular disease by smooth muscle cell proliferation. METHODS: We have previously shown VEGF levels to be increased in juvenile diabetic subjects with no clinical evidence of vascular disease. We have measured serum VEGF using an enzyme linked immunosorbent assay and cellular VEGF expression using flow cytometry in patients with critical limb ischemia prior to and 6 months postamputation to determine whether removal of the ischemic limb leads to changes in systemic endothelial cell function. RESULTS: Baseline VEGF levels were significantly increased in the patient group compared to controls with levels returning to control levels at 6 months postsurgery. Monocyte and neutrophil VEGF expression was significantly reduced in the patient group. Platelet expression of VEGF was also reduced but this failed to reach statistical significance. CONCLUSIONS: The results suggest that it may be useful to determine the balance between VEGF production and cellular receptor expression prior to treatment.