Autonomic neuropathy in Fabry disease: a prospective study using the Autonomic Symptom Profile and cardiovascular autonomic function tests

<p>Abstract</p> <p>Background</p> <p>Fabry patients have symptoms and signs compatible with autonomic dysfunction. These symptoms and signs are considered to be due to impairment of the peripheral nervous system, but findings indicative of autonomic neuropathy in other diseases, such as orthostatic intolerance and male sexual dysfunction, are infrequently reported in Fabry disease. The aim of our study was to investigate autonomic symptoms and cardiovascular autonomic function in a large cohort of male and female Fabry patients.</p> <p>Methods</p> <p>Forty-eight Fabry patients (15 male, 30 treated with enzyme replacement therapy) and 48 sex- and age-matched controls completed a questionnaire on autonomic symptoms (the Autonomic Symptom Profile). Thirty-six Fabry patients underwent cardiovascular function tests.</p> <p>Results</p> <p>The Autonomic Symptom Profile revealed a significantly higher sum score in Fabry patients than in healthy control subjects (22 versus 12), but a relatively low score compared to patients with proven autonomic neuropathy. Fabry patients scored worse than healthy controls in the orthostatic intolerance domain. Scores in the male sexual dysfunction domain were comparable between healthy controls and male Fabry patients. The cardiovascular autonomic function tests revealed only mild abnormalities in seven patients. None of these seven patients showed more than one abnormal test result. Enzyme replacement therapy was not associated with less severe disease, lower ASP scores or less frequent abnormal cardiovascular function test results.</p> <p>Conclusions</p> <p>Male sexual function and autonomic control of the cardiovascular system are nearly normal in Fabry patients, which cast doubt on the general accepted assumption that autonomic neuropathy is the main cause of symptoms and signs compatible with autonomic dysfunction in Fabry disease. Possibly, end-organ damage plays a key role in the development of symptoms and signs in Fabry patients. An exceptional kind of autonomic neuropathy is another but less likely explanation.</p

Postoperative intravenously administered iron sucrose versus postoperative orally administered iron to treat post-bariatric abdominoplasty anaemia (ISAPA): the study protocol for a randomised controlled trial

BACKGROUND: Anaemia and iron deficiency are common complications following post-bariatric abdominoplasty. Given the low oral absorbability of iron resulting from bariatric surgery, it has been hypothesised that postoperative intravenously administered iron supplementation could be used to treat anaemia and to prevent the development of iron deficiency in these patients. METHODS/DESIGN: In this multicentre open-label randomised clinical trial, 56 adult women undergoing post-bariatric anchor-line abdominoplasty will be allocated at a ratio of 1:1 for postoperative supplementation with two intravenously administered applications of 200 mg of iron saccharate or postoperative supplementation with 100 mg of iron polymaltose complex administered orally, twice a day for 8 weeks. The primary outcome is the difference in mean haemoglobin levels between the two groups at eight postoperative weeks. Secondary outcomes evaluated at one, four and eight postoperative weeks include iron profile, reticulocyte count, overall quality of life measured using the Short-Form 36 Health Survey (SF-36) questionnaire, fatigue measured using the Functional Assessment of Chronic Illness Therapy – Fatigue (FACIT-F), adverse effects and postoperative complications. DISCUSSION: This randomised clinical trial aims to evaluate the haematopoietic effectiveness of intravenously administered iron supplementation in patients undergoing post-bariatric abdominoplasty. A more effective recovery of haemoglobin levels could help improve the patients’ quality of life and could provide an improved haematological status in preparation for the subsequent and frequent plastic surgeries these patients undergo. TRIAL REGISTRATION: Clinicaltrials.gov Identifier: NCT01857011 (8 May 2013), Universal Trial Number U111-1169-6223, Brazilian Clinical Trials Registry (REBEC): RBR-2JGRKQ

Leukocyte Tyrosine Kinase Functions in Pigment Cell Development

A fundamental problem in developmental biology concerns how multipotent precursors choose specific fates. Neural crest cells (NCCs) are multipotent, yet the mechanisms driving specific fate choices remain incompletely understood. Sox10 is required for specification of neural cells and melanocytes from NCCs. Like sox10 mutants, zebrafish shady mutants lack iridophores; we have proposed that sox10 and shady are required for iridophore specification from NCCs. We show using diverse approaches that shady encodes zebrafish leukocyte tyrosine kinase (Ltk). Cell transplantation studies show that Ltk acts cell-autonomously within the iridophore lineage. Consistent with this, ltk is expressed in a subset of NCCs, before becoming restricted to the iridophore lineage. Marker analysis reveals a primary defect in iridophore specification in ltk mutants. We saw no evidence for a fate-shift of neural crest cells into other pigment cell fates and some NCCs were subsequently lost by apoptosis. These features are also characteristic of the neural crest cell phenotype in sox10 mutants, leading us to examine iridophores in sox10 mutants. As expected, sox10 mutants largely lacked iridophore markers at late stages. In addition, sox10 mutants unexpectedly showed more ltk-expressing cells than wild-type siblings. These cells remained in a premigratory position and expressed sox10 but not the earliest neural crest markers and may represent multipotent, but partially-restricted, progenitors. In summary, we have discovered a novel signalling pathway in NCC development and demonstrate fate specification of iridophores as the first identified role for Ltk

High Arctic wetting reduces permafrost carbon feedbacks to climate warming

The carbon (C) balance of permafrost regions is predicted to be extremely sensitive to climatic changes. Major uncertainties exist in the rate of permafrost thaw and associated C emissions (33–508 Pg C or 0.04–1.69 °C by 2100) and plant C uptake. In the High Arctic, semi-deserts retain unique soil–plant–permafrost interactions and heterogeneous soil C pools (>12 Pg C). Owing to its coastal proximity, marked changes are expected for High Arctic tundra. With declining summer sea-ice cover, these systems are simultaneously exposed to rising temperatures, increases in precipitation and permafrost degradation. Here we show, using measurements of tundra–atmosphere C fluxes and soil C sources (C) at a long-term climate change experiment in northwest Greenland, that warming decreased the summer CO2 sink strength of semi-deserts by up to 55%. In contrast, warming combined with wetting increased the CO2 sink strength by an order of magnitude. Further, wetting while relocating recently assimilated plant C into the deep soil decreased old C loss compared with the warming-only treatment. Consequently, the High Arctic has the potential to remain a strong C sink even as the rest of the permafrost region transitions to a net C source as a result of future global warming