European Species of Hebeloma Section Theobromina

This paper addresses section Theobromina within the genus Hebeloma (Agaricales). We recognise seven European species within this section, three of which are described as new: Hebeloma alboerumpens, H. griseopruinatum and H. parvicystidiatum. The first two of these species appear to be ectomycorrhizal with Cistaceae: Cistus and Helianthemum. Hebeloma parvicystidiatum is more likely to be in mycorrhizal association with Quercus spp. We also provide a key to the European species within sect. Theobromina and an updated key of known Hebeloma associates of Cistus. Molecular analyses based on multiple loci further illustrate the distinctness of the newly described taxa and provide molecular evidence, supporting the morphological evidence, for the relationship that exists among species of this section. The ITS is the only one from the sequenced loci that, alongside with morphology, distinguishes among all of the species of sect. Theobromina. The section gains most of its molecular support from the MCM7 locus, followed by RPB2.     

Inequality in access to CABG and PCI

Abstract

Non-inferiority trials are questionable when death and serious complications are included among outcomes. The term itself “non-inferiority” is misleading, since such a study would not demonstrate that a new treatment is non-inferior to a control treatment, but simply that the inferiority would not reach a pre-specified level, deemed as acceptable by the designers of the trial. Group cross-over, assay-sensitivity and the need of a placebo arm are major issues for the reliability of non-inferiority trials.

The SYNTAX trial for severe coronary artery disease was designed on a non-inferiority margin of 6.6%. In this paper we show that the SYNTAX designers were ready to accept up to 30% higher rate of death and major adverse events to claim the non-inferiority of percutaneous coronary intervention versus coronary artery bypass grafting. Eventually the SYNTAX study failed because percutaneous patients sustained an even higher rate of adverse events. We propose major caution in performing non-inferiority randomized trials.     

Plasma clots gelled by different amounts of calcium for stem cell delivery

Purpose

Freshly prepared autologous plasma clots may serve as a carrier matrix for expanded multipotent mesenchymal stromal cells (MSCs) or bone marrow cells. By varying the calcium concentration, plasma clots with different properties can be produced. The purpose of this in vitro study was to determine the optimal calcium concentrations for the clotting process, intra-clot cell viability, and clot lysis.

Methods

Different plasma clots were prepared by adding an equal volume of RPMI1640 (with or without MSCs) to citrate plasma (either containing platelets or platelet-free). Clotting was initiated by the addition of CaCl₂ (10 g/100 ml H₂O, 10 % solution). The final concentration of CaCl₂ ranged from 1 to 10 % by volume of plasma. Viability and distribution of the MSCs were analysed by calcein-AM/propidium iodide staining. MSC-embedded plasma clots were dissolved with trypsin (0.25 %), and recovered cells were further incubated for 1 week under cell culture conditions.

Results

The viability of MSCs embedded in clots formed by the addition of 1–8 % by volume CaCl2 was not affected by incubation of up to 1 week. In contrast, clots produced by higher volumes of CaCl₂ solutions (9–10 % by volume of plasma) showed decreased numbers of viable cells. Intra-clot cell proliferation was highest in clots produced by addition of 5 % CaCl₂ by plasma volume. Osteocalcin release was not influenced in platelet-free plasma but decreased in platelet-containing plasma. Morphological analysis of stained recovered MSCs revealed that lysis of the plasma clot did not affect cell morphology or subsequent spontaneous proliferation.

Conclusions

Clot formation and clot stability can be controlled by changing the concentration of CaCl₂ added to plasma. The addition of 5 % CaCl₂ produced a plasma clot with optimal results for stem cell delivery.     

Effect of vitamin D3 treatment on bone density in neurofibromatosis 1 patients: A retrospective clinical study

ObjectivesWe have previously demonstrated reduced bone density and an increased incidence of 25-hydroxy vitamin D₃ (25-OH D₃) deficiency in adults with neurofibromatosis 1 (NF1) compared to healthy controls. Vitamin D₃ is a cheap, safe, and effective supplement in the general population, but its value in NF1 patients has not been demonstrated. This study investigates the therapeutic potential of oral vitamin D₃ on bone mineral density (BMD) in NF1 patients with vitamin D₃ deficiency.MethodsWe measured serum 25-OH D₃, parathyroid hormone, calcium, and bone alkaline phosphatase concentrations, urinary deoxypyridinoline concentrations, and BMD in 35 adults with NF1. Nineteen patients received vitamin D₃ supplementation for 2 years, six patients received supplementation for 1 year and 10 patients received no supplementation. Supplementation was administered in a dose that maintained the serum 25-OH D₃ level above 30 μg/l. BMD was measured again at 1 and 2 years, and biochemical assessments of bone metabolism were measured at least every half year during therapy.ResultsTreated subjects had significantly reduced loss of BMD, as measured by T score at the hip (p = 0.011) and lumbar spine (p = 0.022). The effect on hip BMD was apparent at 1 year in comparison to baseline (p = 0.02) and was greater at 2 years in comparison to measurements at 1 year (p = 0.02).ConclusionsVitamin D₃ supplementation improves BMD in adult NF1 patients. Further studies are needed to elucidate the mechanisms responsible for reduced BMD in NF1 patients.     

ECG changes in patients with acute ethanol intoxication

Objectives. To assess how ethanol in potential lethal serum concentrations affects features of the ECG that may be associated with cardiac arrhythmias. Design. We included 84 patients, who were hospitalised with assumed acute ethanol intoxication. In the emergency room resting ECG was recorded and blood was collected for serum osmolality measurement used as a proxy for ethanol level. Thirty-two also had ECG recorded at discharge. Twenty-seven hospitalised patients without known alcohol ingestion served as controls. ECG segment durations were compared with controls and related to intoxication level. Results. In subjects with moderately elevated to high serum osmolality, the P wave and QTc intervals were prolonged compared with sober subjects. P wave, PR, QRS and QTc intervals were longer when the subjects had high blood ethanol levels (at admission) than at discharge (p-values: 0.0001, 0.0002, 0.010 and < 0.0001 for P wave, PR, QRS and QTc intervals. n = 32). Conclusions. Ethanol at high to very high blood concentration causes several changes in the ECG that might be associated with increased risk of arrhythmias.     

Ischemic QRS prolongation as a predictor of ventricular fibrillation in a canine model

Abstract

Objectives. An acute coronary occlusion and its possible subsequent complications is one of the most common causes of death. One such complication is ventricular fibrillation (VF) due to myocardial ischemia. The severity of ischemia is related to the amount of coronary arterial collateral flow. In dog studies collateral flow has also been shown to be associated with QRS prolongation. The aim of this study was to investigate whether ischemic QRS prolongation (IQP) is associated with impending VF in an experimental acute ischemia dog model. Methods. Degree of IQP and occurrence of VF were measured in dogs (n?=?21) during coronary occlusion for 15?min and also during subsequent reperfusion (experiments conducted in 1984). Results. There was a significant difference in absolute IQP between dogs which developed VF during reperfusion (47?±?29?ms, mean?±?SD) and those which did not (12?±?10?ms; p?=?.001). Conclusions. IQP during acute coronary occlusion is associated with reperfusion VF in an experimental dog model and might therefore be a potential predictor of malignant arrhythmias in patients with acute coronary syndrome.