Neurodevelopmental outcomes and neurophysiological parameters in children with congenital hyperinsulinism

Introduction. Congenital hyperinsulinism is a rare group of genetic disorders resulting in persistent hypoglycemia which can lead to delay of neurodevelopment.Aim. To assess psychomotor development and certain neurophysiological parameters of children treated for congenital hyperin-sulinism.Materials and methods. This prospective and retrospective cohort study included 73 infants with congenital hyperinsulinism admitted to the National Almazov Research Centre from 2017 to 2021. All subjects underwent standard clinical examination including physical and neurological assessment as well as 18F-DOPA PET/CT, genetic testing, electroencephalography. Developmental screening was performed using “Ages and Stages” questionnaire in 33 subjects. Possible risk factors for neurode-velopmental sequelae due to hypoglycemia were analyzed.Results and discussion. Normal neurodevelopment in general was observed in 23 subjects (69%), 10 patients had developmental delay. Focal form of CHI had the greatest modifying effect on positive neurodevelopmental outcome in general. Individual skills such as communication, fine and gross motor, problem solving in children with a focal form of CHI were significantly better than those with a nonfocal forms. Age of manifestation and verification of the disease, the minimum level of glycemia and the maximum level of glucose utilization did not significantly affect the formation of either individual skills (with the exception of gross motor skills) or psychomotor development in general. The indicators of gross motor skills in children with a lower level of glucose utilization turned out to be significantly better. Kaplan-Meier survival analysis showed that the alpha rhythm appearance was significantly earlier in patients with a focal form of CHI and with earlier verification of the diagnosis (<28 days of life).Conclusion. The focal form of the disease has the greatest modifying effect on the positive outcome of the psychomotor development. The age-appropriate gross motor skills were observed more often in the group of children with low glucose disposal rates. The association of the early occurrence of the alpha rhythm with the focal form of congenital hyperinsulinism, as well as with the early verification of the disease, was found

Decay of excited surface electron states in liquid helium and related relaxation phenomena induced by short-wavelength ripplons

Decay rates of excited surface electron states on liquid helium are theoretically studied for different electron confinement potentials and in the presence of quantizing magnetic field. Contributions of both one-ripplon and two-ripplon scattering processes are analyzed. Regarding the decay rate of the first excited surface level (l=2), two-ripplon emission of short wave-length capillary waves is shown to dominate the conventional one-ripplon scattering in two distinct cases: the ambient temperature is low enough, or the surface state excitation energy Δ₂–Δ₁ does not match an excitation energy of the in-plane motion quantized under a strong magnetic field or in a quantum dot. In these cases, magnetic field and confinement cannot essentially reduce the decay rate which is of order of 10⁶ s⁻¹ and does not depend on temperature. Importance of these findings for a microwave resonance experiment is discussed