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The authors describe a vesicular transporter, VST-1, that is required in glutamatergic chemosensory neurons for chemotactic avoidance behavior in C. elegans. VST-1 antagonizes VGLUT-dependent packaging of glutamate into synaptic vesicles and determines the strength of synaptic glutamate signaling.

Bronchopulmonary dysplasia (BPD)-associated pulmonary hypertension (PH) is a well-known complication of prematurity; however, the additional impact of a left-to-right interatrial shunt on this condition remains poorly understood. The aim of the present study was to identify the significance of atrial left-to-right shunt lesions in PH infants with moderate or severe BPD. Methods: The medical records of 383 preterm infants (gestational age of < 32 weeks) who were diagnosed with BPD between 2005 and 2013 were retrospectively reviewed. Baseline characteristics such as interatrial shunts and outcomes were compared between the infants who developed PH (n = 50) and infants who did not (n = 144). Infants with hemodynamically significant residual patent ductus arteriosus were excluded. Among the infants diagnosed with PH (n = 50), the outcomes were compared between the patients with (n = 21) and without atrial shunts (n = 29) at 36 weeks corrected postmenstrual age. Results: Fifty (15%) preterm infants with BPD were diagnosed with PH. The number of infants with a history of atrial shunt lesions was significantly higher in the PH group than in the non-PH group (42% vs. 15.3%, respectively). The adjusted odds ratio for PH in the atrial shunt group was 3.8 (95% confidence interval, 1.8–8.0), compared to PH-BPD infants without an atrial shunt. Conclusion: The presence of an atrial left-to-right shunt was associated with PH in preterm infants with moderate or severe BPD. Close follow up is needed for infants with interatrial shunts, and a more tailored prognostic evaluation and treatment are recommended.

For premature infants with advanced acute abdomen, creating a temporary enterostomy is believed to be an appropriate surgical management. However, there is no consensus regarding the timing of enterostomy reversal. The aim of this study was to determine the optimal timing for enterostomy closure (EC) by analyzing EC-related complications. Methods: This was a retrospective study of preterm infants who underwent enterostomy for suspected acute abdomens and subsequent closure. Results: EC-related complications occurred in 35 of 54 infants (65%). A univariate analysis determined the following risk factors for EC-related complications: lower weight and younger age at the time of EC and a shorter stoma duration. In a multiple logistic regression analysis, the only significant risk factor was a weight under 2660 g at the time of the closure operation. Infants with EC-related complications were ventilated longer, were administered more vasopressors, and were more likely to undergo reoperation. Additionally, these infants required parenteral nutrition for a longer duration, had a longer length of hospital stay after EC, and had a significantly lower weight and height at a corrected age of 7–10 months than infants without EC-related complications. Conclusion: Body weight may be one of the most important factors to consider for minimizing EC-related complications.

Mucolipidosis II (ML II) or inclusion cell disease (I-cell disease) is a rarely occurring autosomal recessive lysosomal enzyme-targeting disease. This disease is usually found to occur in individuals aged between 6 and 12 months, with a clinical phenotype resembling that of Hurler syndrome and radiological findings resembling those of dysostosis multiplex. However, we encountered a rare case of an infant with ML II who presented with prenatal skeletal dysplasia and typical clinical features of severe secondary hyperparathyroidism at birth. A female infant was born at 37+1 weeks of gestation with a birth weight of 1,690 g (T (p.Arg1031X) and c.3456_3459dupCAAC (p.Ile1154GlnfsX3), the latter being a novel mutation. The infant was treated with vitamin D supplements but expired because of asphyxia at the age of 2 months.

McKusick-Kaufman syndrome (MKS) is an autosomal recessive multiple malformation syndrome characterized by hydrometrocolpos (HMC) and postaxial polydactyly (PAP). We report a case of a female child with MKS who was transferred to the neonatal intensive care unit of Seoul National University Children's Hospital on her 15th day of life for further evaluation and management of an abdominal cystic mass. She underwent abdominal sonography, magnetic resonance imaging, genitography and cystoscopy which confirmed HMC with a transverse vaginal septum. X-rays of the hand and foot showed bony fusion of the left third and fourth metacarpal bones, right fourth dysplastic metacarpal bone and phalanx, right PAP and hypoplastic left foot with left fourth and fifth dysplastic metatarsal bones. In addition, she had soft palate cleft, mild hydronephroses of both kidneys, hypoplastic right kidney with ectopic location and mild rotation, uterine didelphys with transverse vaginal septum and low-type imperforated anus. She was temporarily treated with ultrasound-guided transurethral aspiration of the HMC. Our patient with HMC and PAP was diagnosed with MKS because she has two typical abnormality of MKS and she has no definite complications of retinal disease, learning disability, obesity and renal failure that develop in Bardet-Biedl syndrome, but not in MKS until 33 months of age. Here, we describe a case of a Korean patient with MKS.

Spontaneous pneumomediastinum in the absence of predisposing risk factors has been rarely observed in full-term neonates. A 3-day-old neonate, delivered vaginally at term without any perinatal complications or signs of respiratory difficulty, was referred to the Seoul National University Children’s Hospital because of reduced heart sound detected during routine neonatal examination. Chest computed tomography (CT) showed air collection in the anterior mediastinum. The baby developed respiratory distress on the fourth day and required supplemental oxygen. On the seventh day, there was no sign of respiratory difficulty, and x-ray examination showed no demonstrable pneumomediastinum. Hence, careful neonatal physical examination is essential during the postnatal assessment of newborns, and spontaneous pneumomediastinum should be considered when a healthy newborn presents with reduced heart sound.

Objective: This study introduces a novel technique utilizing a drill stopper to limit drill penetration depth and to prevent iatrogenic injuries, specifically neurovascular damage, in orthopedic surgeries. Orthopedic surgeries frequently involve the use of drills, which are essential tools for various procedures. However, improper handling of drills can lead to iatrogenic soft tissue injuries, causing severe consequences such as permanent disability or life-threatening complications. To address this issue, we propose the use of a drill stopper as a safeguard to prevent excessive drill penetration and reduce the risk of soft tissue damage during surgery. Materials and Methods: The study involved 32 orthopedic surgeons, half of whom were experienced and the other half inexperienced. Synthetic femur bone models (Synbone) were used for drilling exercises, employing four configurations: a sharp drill bit without a stopper (SF, Sharp Free), a sharp drill bit with a stopper (SS, Sharp Stopper), a blunt drill bit without a stopper (BF, Blunt Free), and a blunt drill bit with a stopper (BS, Blunt Stopper). Each participant conducted three trials for each configuration, and the penetration depth was measured after each trial. Results: For experienced surgeons, the average penetration depths were 3.83 (±1.826)mm for SF, 11.02 (±3.461)mm for BF, 2.88 (±0.334)mm for SS, and 2.75 (±0.601)mm for BS. In contrast, inexperienced surgeons had average depths of 8.52 (±4.608)mm for SF, 18.75 (±4.305)mm for BF, 2.96 (±0.683)mm for SS, and 2.83 (±0.724)mm for BS. Conclusion: The use of a drill stopper was highly effective in controlling drill penetration depth and preventing iatrogenic injuries during orthopedic surgeries. We recommend its incorporation, particularly when using a blunt drill bit or when an inexperienced surgeon operates in an anatomically unfamiliar area. Using the drill stopper, the risk of severe injuries from excessive drill penetration can be minimized, leading to improved patient safety and better surgical outcomes.

Recently, deep neural network (DNN) acceleration has been critical for hardware systems from mobile/edge devices to high-performance data centers. Especially, for on-device AI, there have been many studies on hardware numerical precision reduction considering the limited hardware resources of mobile/edge devices. Although layer-wise mixed-precision leads to computational complexity reduction, it is not straightforward to find a well-balanced layer-wise precision scheme since it takes a long time to determine the optimal precision for each layer due to the repetitive experiments and the model accuracy, the fundamental measure of deep learning quality, should be considered as well. In this paper, we propose the layer-wise mixed precision scheme which can significantly reduce the time required to determine the optimal hardware numerical precision with Signal-to-Quantization Noise Ratio (SQNR)-based analysis. In addition, the proposed scheme can take the hardware complexity into consideration in terms of the number of operations (OPs) or weight memory requirement of each layer. The proposed method can be directly applied to inference, meaning that users can utilize well-trained neural network models without the need for additional training or hardware units. With the proposed SQNR-based analysis, for SSDlite and YOLOv2 networks, the analysis time required for layer-wise precision determination is reduced by more than 95% compared to conventional mean Average Precision(mAP)-based analysis. Also, with the proposed complexity-aware schemes, the number of OPs and weight memory requirement can be reduced by up to 86.14% and 78.03%, respectively, for SSDlite, and by up to 51.93% and 50.62%, respectively, for YOLOv2, with negligible model accuracy degradation.