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The amount of Insulin Growth Factor 2 (IGF2) controls the rate of embryonal and postnatal growth. The IGF2 and adjacent H19 are the imprinted genes of the telomeric cluster in the 11p15 chromosomal region regulated by differentially methylated regions (DMRs) or imprinting centers (ICs): H19/IGF2:IG-DMR (IC1). Dysregulation due to IC1 Loss-of-Methylation (LoM) or Gain-of-Methyaltion (GoM) causes Silver-Russell syndrome (SRS) or Beckwith-Wiedemann syndrome (BWS) disorders associated with growth retardation or overgrowth, respectively. Specific features define each of the two syndromes, but isolated asymmetry is a common cardinal feature, which is considered sufficient for a diagnosis in the BWS spectrum. Here, we report the case of a girl with right body asymmetry, which suggested BWS spectrum. Later, BWS/SRS molecular analysis identified IC1_LoM revealing the discrepant diagnosis of SRS. A clinical re-evaluation identified a relative macrocephaly and previously unidentified growth rate at lower limits of normal at birth, feeding difficulties, and asymmetry. Interestingly, and never previously described in IC1_LoMSRS patients, since the age of 16, she has developed hand-writer's cramps, depression, and bipolar disorder. Trio-WES identified a VPS16 heterozygous variant [NM_022575.4:c.2185C>G:p.Leu729Val] inherited from her healthy mother. VPS16 is involved in the endolysosomal system, and its dysregulation is linked to autosomal dominant dystonia with incomplete penetrance and variable expressivity. IGF2 involvement in the lysosomal pathway led us to speculate that the neurological phenotype of the proband might be triggered by the concurrent IGF2 deficit and VPS16 alteration. [ABSTRACT FROM AUTHOR]

Abstract: For the amalgam cell {MxHg1−x|MCl2 (m)|AgCl |Ag} (with M=Sr, Ba) the potential difference E has been measured as a function of the mole fraction xM of the metal M in amalgams and of the molality m of MCl2 in {methanol+water} and {ethanol+water} solvent mixtures Z={A+W} with mass fractions of alcohol wA⩽0.50 of alcohol, at temperature 298.15 K. The respective molal-scale standard potential differences have been determined together with the relevant activity coefficients γ± as functions of the MCl2 molality. The dependence on the alcohol mole fraction in the solvent mixture within the ranges explored turns out to be linear for both of these two metals M in the amalgams studied. Of course, also the molal-scale standard Gibbs free energy change , which constitutes the “primary medium effect” upon transferring MCl2 from pure water to the (alcohol+water) mixture, is linear in xA. In the same context, following Feakins and French’s treatment, which implies volume fraction statistics, the relevant primary medium effects upon MCl2 on the mol·dm−3 scale have been analysed in terms of the expected linear relation of against the logarithm of water volume fraction, leading to primary hydration numbers for SrCl2 and BaCl2, respectively, in acceptable agreement with Bockris’ data based on different methods. [Copyright &y& Elsevier]

The potential difference E of the amalgam cell {MxHg1 − x|MCl or MCl2 (m)| AgCl |Ag} (M=Rb, Cs, Sr, Ba) has been measured as a function of the mole fraction xM of M metal in amalgams and of the molality m of MCl (or MCl2) in (acetonitrile [A] + water [W]) solvent mixtures containing up to acetonitrile mass fraction wA=0.50, at T=298.15 K. The respective molal-scale standard potential differences E∘m have been determined together with the relevant activity coefficients γ± functions of the MCl (or MCl2) molality. The E∘m dependence on the mole fraction xA of acetonitrile in the solvent mixture within the range explored turns out to be linear for all the four metals M in the amalgams considered. Of course, also the difference ([E∘m]W−[E∘m]A), which is a measure of the primary medium effect upon transferring MCl (or MCl2) from pure water [W] to the acetonitrile [A] mixture, is linear in xA.In this context, following Feakins and French''s scheme, which implies volume fraction statistics, analysis of the relevant mol · dm−3 scale primary medium effects, i.e., ([E∘c]W−[E∘c]A), upon MCl (or MCl2), as a linear function of the logarithm of water volume fraction, would lead to primary hydration numbers of 4.2 for RbCl, 4.0 for CsCl, 10.7 for SrCl2, and 10.3 for BaCl2, respectively, in acceptable agreement with literature data by Bockris based on different methods. [Copyright &y& Elsevier]