ICM Partners

About: ICM Partners is a based out in . It is known for research contribution in the topics: Population & Breast cancer. The organization has 1311 authors who have published 1521 publications receiving 33745 citations. The organization is also known as: International Creative Management Partners.

Focal and abnormally persistent paralysis associated with congenital paramyotonia.

Abstract: Mutations of the skeletal muscle voltage-gated sodium channel (NaV1.4) are an established cause of several clinically distinct forms of periodic paralysis and myotonia. Focal paresis has sometimes already been described. We report a case with atypical clinical manifestation comprising paramyotonia and cold-induced persistent and focal paralysis. A 27-year-old woman presented with paramyotonia congenita since her childhood. She experienced during her childhood one brief episode of generalised weakness. At the age of 27, she experienced a focal paresis lasting for several months. The known mutation p.Val1293Ile was found in the muscle sodium channel gene (SCN4A). Channel inactivation is involved in most Na+ channelopathies. Fast inactivation is known to be responsible for the myotonia phenotype. We hypothesise that the V1293I mutation may also alter the slow inactivation in specific conditions, for example, prolonged cold exposure or prolonged and intensive exercise. This observation broadens the spectrum of clinical manifestations of this sodium channel mutation.

A 1H NMR study on the interaction of aminoxyl paramagnetic probes with unfolded peptides

Abstract: The use of soluble spin labels to filter out the cross peaks of outer proton nuclei in 2D NMR spectra has been proposed as a general method to obtain structural information for complex molecules. Here the paramagnetic effects observed on backbone protons of an unfolded 27 amino acid peptide are discussed. The lack of any differential intensity change of the NH–Hα cross-peaks in TOCSY spectra is suggested as an additional general criterion for the identification of unfolded structures.

What mediates postoperative risk in obstructive sleep apnea: airway obstruction, nocturnal hypoxia, or both?

Abstract: To the Editor, Obstructive sleep apnea (OSA) is known to be an independent risk factor for postoperative complications. The apnea–hypopnea index (AHI) – i.e., the number of apnea and hypopnea events per hour of sleep during overnight polysomnographic (PSG) monitoring – has typically served to classify the severity of OSA (with severe OSA defined by an AHI[30). A recently reported matched cohort study by Mutter et al. that measured the severity of OSA by AHI during PSG monitoring appears to constitute a landmark for identifying OSA patients at risk of postoperative complications. In that study, increased severity of OSA was associated with increased risk of complications, although only the data for the severe OSA group reached statistical significance. Hypoxic events in OSA patients may have significant pathophysiological consequences. Although confirmatory prospective studies are lacking, we hypothesize that these hypoxia-mediated inflammatory modifications could increase the risk of postoperative complications, acting cumulatively with the AHI or even mediating its effects entirely. An oxygen desaturation index (ODI) can also be derived from the PSG analysis and can be used as an independent measure of hypoxia. The ODI represents the number of times per hour that the capillary blood oxygen saturation drops by C4% from baseline during overnight PSG monitoring. We recently reported the results of a study (EudraCT: 2006-006558-92) that outlined the development of the DES-OSA score (the DES part of the acronym being derived from the initials of the investigators involved in its development) in 139 patients. The Figure shows the relation between the ODI and the AHI from that study. Clearly, some, but not all, patients with severe OSA (AHI [ 30) experienced nocturnal hypoxia. In the patients with severe OSA and hypoxia, the ODI varied considerably, with minimum and maximum values of 2 and 92 events per hour, respectively, although the median [interquartile range] was only 25 [10–37] events per hour. Among patients with severe OSA, 33% encountered no (ODI \\ 5 events per hour) or mild (ODI 5–15) nocturnal hypoxia; 29% had moderate nocturnal hypoxia (ODI 15–30); and 38% had severe nocturnal hypoxia (ODI[30). Wide variation in the preoperative and postoperative ODIs among surgical patients with and without OSA has also been noted, but the relation of the ODI to the AHI and postoperative complications was not assessed. Mutter et al. found that only severe OSA patients were at a significantly increased risk of postoperative complications. Whether hypoxemic and non-hypoxemic severe OSA patients share the same risk or only patients with both severe OSA and hypoxia are at risk is unknown. Our preliminary data suggest that future studies investigating postoperative complications in OSA patients E. P. Deflandre, MD (&) Department of Anaesthesia, Clinique Saint-Luc of Bouge, Belgium & Cabinet Medical ASTES & University of Liege, Liege, Belgium e-mail: eric.deflandre@gmail.com