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The article discusses a study which applied a next generation sequencing methodology to characterise three alpha globin cluster duplications, permitting to-the-base resolution in several cases of beta thalassaemia intermedia co-inheritance. It cites various mechanisms of increasing alpha globin complex. The use of the Qiagen Symphony whole blood midi kit to extract genomic DNA is also discussed.

Diet-induced weight loss in women may be associated with decreases not only in plasma levels of low-density lipoprotein cholesterol (LDL-C), but also in high-density lipoprotein cholesterol (HDL-C). Whether a decrease in HDL-C is associated with altered HDL function is unknown. One hundred overweight or obese women (age 46 ± 11 years, 60 black; 12 diabetic) were enrolled in the 6-month program of reduced fat and total energy diet and low-intensity exercise. Serum cholesterol efflux capacity was measured in 3H-cholesterol-labeled BHK cells expressing ABCA1, ABCG1, or SR-B1 transporters and incubated with 1% apolipoprotein B (apoB)-depleted serum. Antioxidant properties of HDL were estimated by paraoxonase-1 (PON1) activity and oxygen radical absorbance capacity (ORAC). Endothelial nitric oxide synthase (eNOS) activation was measured by conversion of L-arginine to L-citrulline in endothelial cells incubated with HDL from 49 subjects. Participants achieved an average weight loss of 2.2 ± 3.9 kg (P < 0.001), associated with reductions in both LDL-C (−6 ± 21 mg/dl, P = 0.004) and HDL-C (−3 ± 9 mg/dl, P = 0.016). Cholesterol efflux capacity by the ABCA1 transporter decreased by 10% (P = 0.006); efflux capacities by the ABCG1 and SR-B1 transporters were not significantly altered. ORAC decreased by 15% (P = 0.018); neither PON1 activity nor eNOS activation was significantly altered by reduction in HDL-C. Findings were similar for diabetic and nondiabetic subjects. Diet-induced weight loss in overweight or obese women is associated with a decrease in HDL-C levels, but overall HDL function is relatively spared, suggesting that decrease in HDL-C in this setting is not deleterious to cardiovascular risk. [ABSTRACT FROM AUTHOR]

Summary Normally, cell free haemoglobin is bound by haptoglobin and efficiently cleared. However, the chronic haemolysis in sickle cell disease (SCD) overwhelms haptoglobin binding capacity and protein turnover, resulting in elevated cell free haemoglobin. Cell free haemoglobin acts as both a scavenger of vasoactive nitric oxide and a pro-oxidant. In addition, methaemoglobin (metHb) releases the haem moiety, which can bind to albumin to form methaemalbumin (metHSA). This study used electron paramagnetic resonance to detect metHSA in SCD plasma and demonstrated that haptoglobin prevents haem transfer from metHb to HSA. MetHSA may either provide a second line of defence against haemoglobin/haem-mediated oxidation or contribute to the pro-oxidant environment of SCD plasma. We demonstrated that HSA inhibited oxidative protein modification induced by metHb. Additionally, we showed that while metHb induced haem oxygenase 1 (HO-1), an indicator of oxidative stress, HSA attenuated metHb induction of this enzyme, thereby limiting the potential benefits of HO-1. Furthermore, HO-1 induction by metHSA was less than HO-1 induction by equimolar metHb not bound to albumin. Our findings confirm the presence of metHSA in SCD and suggest that haem transfer from metHb to HSA reduces the oxidative effects of free haemoglobin/haem on endothelium with both beneficial (reduced protein oxidation) and potentially harmful (reduced HO-1 induction) outcomes. [ABSTRACT FROM AUTHOR]

Abstract: Epithelial-to-mesenchymal transition (EMT) has been implicated in various physiological and pathological events. In this study, we found that the synthetic glucocorticoid dexamethasone (Dex) can inhibit transforming growth factor-beta1-induced EMT and cell migration. We also demonstrated that Dex inhibits EMT through a mechanism involving the suppression of ROS generation. Surprisingly, Dex alone induced mesenchymal-to-epithelial transition (MET). Dexamethasone treatment abolished Snail1 binding to the E-cadherin promoter, suggesting that suppression of Snail1 contributes to the above roles of Dex. Our findings demonstrate that Dex functions as both a suppressor of EMT and as an inducer of MET and therefore may be implicated in certain pathophysiological events. [ABSTRACT FROM AUTHOR]

Pulmonary hypertension (PH) is a common complication of haemolytic anaemia. Intravascular haemolysis leads to nitric oxide (NO) depletion, endothelial and smooth muscle dysregulation, and vasculopathy, characterized by progressive hypertension. PH has been reported in patients with paroxysmal nocturnal haemoglobinuria (PNH), a life-threatening haemolytic disease. We explored the relationship between haemolysis, systemic NO, arginine catabolism and measures of PH in 73 PNH patients enrolled in the placebo-controlled TRIUMPH (Transfusion Reduction Efficacy and Safety Clinical Investigation Using Eculizumab in Paroxysmal Nocturnal Haemoglobinuria) study. At baseline, intravascular haemolysis was associated with elevated NO consumption (P < 0.0001) and arginase-1 release (P < 0.0001). Almost half of the patients in the trial had elevated levels (> or =160 pg/ml) of N-terminal pro-brain natriuretic peptide (NT-proBNP), a marker of pulmonary vascular resistance and right ventricular dysfunction previously shown to indicate PH. Eculizumab treatment significantly reduced haemolysis (P < 0.001), NO depletion (P < 0.001), vasomotor tone (P < 0.05), dyspnoea (P = 0.006) and resulted in a 50% reduction in the proportion of patients with elevated NT-proBNP (P < 0.001) within 2 weeks of treatment. Importantly, the significant improvements in dyspnoea and NT-proBNP levels occurred without significant changes in anaemia. These data demonstrated that intravascular haemolysis in PNH produces a state of NO catabolism leading to signs of PH, including elevated NT pro-BNP and dyspnoea that are significantly improved by treatment with eculizumab.