This study aimed to evaluate the capability of a piezoelectric sensor to detect a heart murmur in patients with congenital heart defects. Heart sounds and murmurs were recorded using a piezoelectric sensor and an electronic stethoscope in healthy neonates (n = 9) and in neonates with systolic murmurs caused by congenital heart defects (n = 9) who were born at a hospital. Signal data were digitally filtered by high-pass filtering, and the envelope of the processed signals was calculated. The amplitudes of systolic murmurs were evaluated using the signal-to-noise ratio and compared between healthy neonates and those with congenital heart defects. In addition, the correlation between the amplitudes of systolic murmurs recorded by the piezoelectric sensor and electronic stethoscope was determined. The amplitudes of systolic murmurs detected by the piezoelectric sensor were significantly higher in neonates with congenital heart defects than in healthy neonates (p < 0.01). Systolic murmurs recorded by the piezoelectric sensor had a strong correlation with those recorded by the electronic stethoscope (ρ = 0.899 and p < 0.01, respectively). The piezoelectric sensor can detect heart murmurs objectively. Mechanical improvement and automatic analysis algorithms are expected to improve recording in the future.

Gain-of-function mutations in voltage-gated sodium channels (NaV1.7, NaV1.8, and NaV1.9) are known causes of inherited pain disorders. Identification and functional assessment of new NaV1.7 mutations could help elucidate the phenotypic spectrum of NaV1.7 channelopathies. We identified a novel NaV1.7 mutation (E44Q in exon 2) that substitutes a glutamic acid residue for glutamine in the cytoplasmic N-terminus of NaV1.7 in a patient with paroxysmal pain attacks during childhood and his family who experienced similar pain episodes. To study the sodium channel's function, we performed electrophysiological recordings. Voltage-clamp recordings revealed that the mutation increased the amplitude of the non-inactivating component of the sodium current, which might facilitate channel opening. These data demonstrate that E44Q is a gain-of-function mutation in NaV1.7, which is consistent with our patient's pain phenotype.

Acid sphingomyelinase deficiency (ASMD) is currently treatable with olipudase alfa, increasing the need for early newborn screening (NBS). We conducted a two-center pilot cohort study to characterize dried blood spot (DBS) acid sphingomyelinase (ASM) activity in Japanese neonates in the neonatal intensive care unit (NICU). ASM activity was measured by flow injection-tandem mass spectrometry in 244 NICU-admitted neonates (gestational age 25–41 weeks; birth weight 773–4201 g); longitudinal paired samples were available in 34 neonates with birth weight < 2000 g and concurrent hematology in 43 neonates. The mean ASM activity was 3.7 ± 1.2 μmol/h/L (95% confidence interval, 3.54–3.84; range, 1.7–11.6), with a right-skewed distribution. ASM activity correlated positively with birth weight (r = 0.184, p = 0.0039), gestational age (r = 0.219, p = 0.0006), and lymphocyte count (ρ = 0.394, p = 0.0089) and negatively with hematocrit (ρ = −0.372, p = 0.014). In neonates with a birth weight < 2000 g, ASM increased significantly on repeat sampling (mean difference, 1.60 μmol/h/L; p < 0.0001; Cohen’s d = 0.912). These findings support NICU-specific reference ranges, hematology-informed interpretations, repeat testing after maturation, and the use of second-tier biomarkers for ASMD NBS implementation in Japan.