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Abstract Background Zellweger syndrome (ZS) is a peroxisome biogenesis disorder due to mutations in any one of 13 PEX genes. Increased incidence of ZS has been suspected in French-Canadians of the Saguenay-Lac-St-Jean region (SLSJ) of Quebec, but this remains unsolved. Methods We identified 5 ZS patients from SLSJ diagnosed by peroxisome dysfunction between 1990–2010 and sequenced all coding exons of known PEX genes in one patient using Next Generation Sequencing (NGS) for diagnostic confirmation. Results A homozygous mutation (c.802_815del, p.[Val207_Gln294del, Val76_Gln294del]) in PEX6 was identified and then shown in 4 other patients. Parental heterozygosity was confirmed in all. Incidence of ZS was estimated to 1 in 12,191 live births, with a carrier frequency of 1 in 55. In addition, we present data suggesting that this mutation abolishes a SF2/ASF splice enhancer binding site, resulting in the use of two alternative cryptic donor splice sites and predicted to encode an internally deleted in-frame protein. Conclusion We report increased incidence of ZS in French-Canadians of SLSJ caused by a PEX6 founder mutation. To our knowledge, this is the highest reported incidence of ZS worldwide. These findings have implications for carrier screening and support the utility of NGS for molecular confirmation of peroxisomal disorders.

A correction to the article "Thymic stromal lymphopoietin: An immune cytokine gene associated with the metabolic syndrome and blood pressure in severe obesity" that was published in the 2012 issue is presented.

• 11B solid-state NMR studies on Sc 2 Ir 6-x Ni x B vs temperature and Ni substitution. • We present an atomic-level view of the lattice via quadrupolar interactions and paramagnetic effects upon Ir replacement. • NMR highlights short-range ordering and structural displacement that is not visible by XRD. • Nanoscale phase separation of ordered and disordered phases was studied by solid-state NMR. Intermetallic borides, such as the Sc 2 Ir 6- x Ni x B (x = 0–6) series, exhibit technologically relevant physicochemical properties, that are all associated to boron ordering. X-ray diffraction has not yet fully investigated the effect of Ir substitution by Ni on the boron arrangement of these borides, primarily due to its weak scattering factor. Herein we employ 11B-NMR to probe the boron ordering of Sc 2 Ir 6- x Ni x B series at atomic scale, overcoming limitations on low- Z materials. Across the Ni-substitution range, the spectral parameters and spin-lattice relaxation rates (T 1 − 1) were responsive to changes in crystal symmetry and valence charges. The spectral analysis and T 1 − 1 vs. x reveal that Ni substitution causes phase separation at the nanoscale between ordered and disordered borides. For x = 3, T 1 − 1 is T -independent, indicating a relaxation mechanism caused by paramagnetic centers whereas x = 5 follows a T2 -dependence that is consistent with band structure predictions of a reduction in the density of states, correlated with sharp features near the Fermi level. [Display omitted] [ABSTRACT FROM AUTHOR]

The presence of one-dimensional trigonal arrangements of chromium atoms (Cr 3 ) in the structure of TiCrIr 2 B 2 leads to a magnetic transition near ambient temperature. Herein we report an investigation of the nature of electronic and magnetic properties of TiCrIr 2 B 2 via ab initio calculations together with 11 B NMR Knight shift ( K ) and spin-lattice relaxation rate (1/ T 1 ) analysis. The presence of a characteristic rectangular powder pattern below 280 K, absence of a Korringa relation, strong enhancement of 1/ T 1 .T at low temperatures and weak temperature dependence of K indicate competition between antiferromagnetic and ferromagnetic spin fluctuations in the itinerant d -band electrons, in agreement with ab initio calculations. One-dimensional trigonal arrangements of magnetically active elements in intermetallic compounds, as is found in TiCrIr 2 B 2 , are quite rare and could lead to exotic phenomena such as spin-chirality and quantum criticality in low-dimensional frustrated lattices. [ABSTRACT FROM AUTHOR]

para-Hydrogen induced polarization is a technique of magnetic resonance hyperpolarization utilizing hydrogen's para-spin state for generating signal intensities at magnitudes far greater than state-of-the-art magnets. Platinum nanoparticle-catalysts with cysteine-capping are presented. The measured polarization is the highest reported to date in water, paving pathways for generating medical imaging contrast agents. [ABSTRACT FROM AUTHOR]