In the process of creating sustainable heat and power production systems it is important to find alternative, renewable fuels that are carbon dioxide neutral. Preferably these fuels should be domestic, thus diminishing the need for transportation. One option could be to use existing residues from local agriculture and food production. Development of combustion methods suitable for such residues is presently being pursued by a number of companies. Because many biomass fuels have compositions that makes them inclined to cause ash sintering problems and emissions of acid gases, there may be a need for the use of additives to decrease such problems. The aim of this work was to examine the ash characteristics of some agricultural crops and residues and to find mixtures of fuels and additives that can form the basis for production of fuel pellets with minimal problems. The work is focused on biomass fuel pellets for small-scale grate-fired combustors. Three additives (limestone powder, kaolin, and sodium bicarbonate) were investigated regarding their effects on the ash melting behavior. The results show that calcium carbonate and kaolin both serve as good additives to prevent the formation of slag. The best antislagging effect was achieved when both additives were used. Sodium bicarbonate can be used as a sulfur binding additive, but this cannot be recommended since it increases the slag formation considerably. The conclusion is that combustion of agricultural crops and residues may be hampered by problems such as slag formation and ash fouling. However, through the use of suitable additives, the ash sintering characteristics can be improved significantly. This means that agricultural residues can be competitive fuels on the energy market in the future.

Background Inflammation may play an important role in type 2 diabetes. It has been proposed that dietary strategies can modulate inflammatory activity.Methods We investigated the effects of diet on inflammation in type 2 diabetes by comparing a traditional low-fat diet (LFD) with a low-carbohydrate diet (LCD). Patients with type 2 diabetes were randomized to follow either LFD aiming for 55–60 energy per cent (E%) from carbohydrates (n = 30) or LCD aiming for 20 E% from carbohydrates (n = 29). Plasma was collected at baseline and after 6 months. C-reactive protein (CRP), interleukin-1 receptor antagonist (IL-1Ra), IL-6, tumour necrosis factor receptor (TNFR) 1 and TNFR2 were determined.Results Both LFD and LCD led to similar reductions in body weight, while beneficial effects on glycaemic control were observed in the LCD group only. After 6 months, the levels of IL-1Ra and IL-6 were significantly lower in the LCD group than in the LFD group, 978 (664–1385) versus 1216 (974–1822) pg/mL and 2.15 (1.65–4.27) versus 3.39 (2.25–4.79) pg/mL, both P < 0.05.Conclusions To conclude, advice to follow LCD or LFD had similar effects on weight reduction while effects on inflammation differed. Only LCD was found significantly to improve the subclinical inflammatory state in type 2 diabetes.

Clinical findings highlighted the inverse association between lutein and IL-6 in CAD patients. Anti-inflammatory effects of lutein in PBMCs from CAD patients were consolidated in ex vivo experiments. Taken together, these results show that lutein has the potential to play a role in resolution of chronic inflammation in CAD patients.

ObjectiveThere is a growing interest for matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs) in plasma as novel biomarkers in coronary artery disease (CAD). We aimed to identify the sources of MMP-8, MMP-9, TIMP-1 and TIMP-2 among peripheral blood cells and further explore whether gene expression or protein release was altered in patients with stable angina pectoris (SA).MethodsIn total, plasma MMP-9 was measured in 44 SA patients and 47 healthy controls. From 10 patients and 10 controls, peripheral blood mononuclear cells (PBMC) and neutrophils were isolated and stimulated ex vivo. MMPs, TIMPs and myeloperoxidase were measured in plasma and supernatants by ELISA. The corresponding gene expression was measured by real-time PCR.ResultsNeutrophils were the dominant source of MMP-8 and MMP-9. Upon moderate stimulation with IL-8, the neutrophil release of MMP-9 was higher in the SA patients compared with controls (p<0.05). In PBMC, the TIMP-1 and MMP-9 mRNA expression was higher in SA patients compared with controls, p<0.01 and 0.05, respectively. There were no differences in plasma levels between patients and controls except for TIMP-2, which was lower in patients, p<0.01.ConclusionMeasurements of MMPs and TIMPs in plasma may be of limited use. Despite similar plasma levels in SA patients and controls, the leukocyte-derived MMP-9 and TIMP-1 are significantly altered in patients. The findings indicate that the leukocytes are more prone to release and produce MMP-9 in symptomatic and angiographically verified CAD—a phenomenon that may have clinical implications in the course of disease.

ObjectiveThere is emerging evidence for CD8 + T cell alterations in blood from patients with coronary artery disease (CAD). We examined whether the distribution and phenotype of CD8 + CD56 + T cells differed according to the clinical manifestation of CAD. MethodsPatients with acute coronary syndrome (ACS, n=30), stable angina (SA, n=34) and controls (n=36) were included. Blood was collected before and up to 12 months after referral for coronary investigation. CD8 + CD56 + T cells were assessed by flow cytometry for expression of surface markers, apoptosis, and intracellular expression of cytokines. ResultsThe proportions of CD8 + CD56 + T cells were significantly higher in both ACS and SA patients compared with controls, and remained so after 3 and 12 months. This was independent of age, sex, systemic inflammation and cytomegalovirus seropositivity. ConclusionThe persistent accumulation of CD8 + CD56 + T cells in ACS and SA patients share several features with immunological aging. It also contributes to a larger IFN-γ + pool in blood, and may thereby hypothetically drive the atherosclerotic process in a less favorable direction.

ObjectiveRegulatory T cells (Tregs) are considered atheroprotective, and low levels have been associated with the acute coronary syndrome (ACS), particularly non‐ST elevation (NSTE)‐ACS. However, the functional properties as well as homeostasis of Tregs are mainly unknown in coronary artery disease (CAD). Here, we investigated the composition and functional properties of naïve (n) and memory (m)Tregs in patients with NSTE‐ACS and in patients 6–12 months post‐ACS.MethodsBased on the expression of CD25, FOXP3, CD127, CD45RA, CD39 and CTLA‐4, Treg subsets were defined by flow cytometry in whole blood or isolated CD4+ T cells. The functional properties of nTregs and mTregs were examined in terms of proliferative capacity and modulation of cytokine secretion. To understand the potential consequences of Treg defects, we also investigated correlations with lipopolysaccharide (LPS)‐induced cytokine secretion and ultrasound‐defined carotid atherosclerosis.ResultsBoth NSTE‐ACS and post‐ACS patients exhibited reduced levels of nTregs (P < 0.001) compared with healthy control subjects, but without compensatory increases in mTregs. Both nTregs and mTregs from patients showed significantly lower replicative rates and impaired capacity to modulate T‐cell proliferation and secretion of interferon‐gamma and IL‐10. The Treg defect was also associated with LPS‐induced cytokine secretion and increased burden of carotid atherosclerosis.ConclusionOur results demonstrate a functional and homeostatic Treg defect in patients with NSTE‐ACS and also in stabilized patients 6–12 months after ACS. Moreover, this defect was associated with a subclinical proinflammatory and atherogenic state. We believe that the failure to preserve Treg function and homeostasis reflects a need for immune‐restoring strategies in CAD.

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