Genetic Analysis of UGT1A1 Polymorphisms Using Preserved Dried Umbilical Cord for Assessing the Potential of Neonatal Jaundice as a Risk Factor for Autism Spectrum Disorder in Children

Journal of Autism and Developmental Disorders - Neonatal jaundice has been suggested as a perinatal risk factor for autism spectrum disorder (ASD). We examined UGT1A1 polymorphisms to assess the...     

Unilateral nephrectomy for young infants with congenital nephrotic syndrome of the Finnish type

Clinical and Experimental Nephrology - The management of congenital nephrotic syndrome of the Finnish type (CNF) is challenging. It is difficult to withdraw intravenous albumin infusions, resulting...     

Mitochondrial respiratory chain complex IV deficiency complicated with chronic intestinal pseudo‐obstruction in a neonate

A female infant born at 36 weeks gestational age with birthweight 2135 g, and who developed respiratory disorder, hyperlactacidemia and hypertrophic cardiomyopathy after birth, was admitted to hospital at 3 days of age. After admission, bilious emesis, abdominal distention, and passage disorder of the gastrointestinal tract were resistant to various drugs. Exploratory laparotomy was performed at 93 days of age, but no organic lesions were identified and normal Meissner/Auerbach nerve plexus was confirmed, which led to a clinical diagnosis of chronic intestinal pseudo‐obstruction (CIPO). She was diagnosed with mitochondrial respiratory chain complex IV deficiency on histopathology of the abdominal rectus muscle and enzyme activity measurement. This is the first report of a neonate with mitochondrial respiratory chain complex deficiency with intractable CIPO. CIPO can occur in neonates with mitochondrial respiratory chain disorder, necessitating differential diagnosis from Hirschsprung disease.     

Impairment of the discrimination of the direction of single-whisker stimulation induced by the lemniscal pathway lesion

In the rodent somatosensory system, stimulus information received by the whiskers is relayed to the barrel cortex via two parallel pathways, the lemniscal pathway and the paralemniscal pathway. The lemniscal pathway includes the principal trigeminal nucleus (Pr5) and the ventral posteromedial thalamic nucleus (VPm). The paralemniscal pathway includes the spinal trigeminal subnucleus interpolaris (Sp5i) and the medial division of posterior thalamic nucleus (POm). The purpose of this study was to investigate the roles of those pathways in perceptions of the direction of the single-whisker stimulation in the rat. Rats were trained to perform a go/no-go task that required the discrimination of forward or backward stimulation applied to their single whisker. When a selective lesion was made in VPm or Pr5, error rate for the task performance increased significantly. In contrast, when a selective lesion was made in POm or Sp5i, we found no significant change in performance. These results suggest that the lemniscal pathway plays more important roles in a discrimination of stimulus direction applied to the single whisker.     

Quantitative evaluation of ventricular dilatation using computed tomography in infants with congenital cytomegalovirus infection

Background

Infants with congenital cytomegalovirus infection (CCMVI) may develop brain abnormalities such as ventricular dilatation, which may potentially associate with sensorineural hearing loss. There is currently no recognized method for quantitative evaluation of ventricle size in infants with CCMVI. Our objectives were to establish a method for quantitative evaluation of ventricle size using computed tomography (CT) in infants with CCMVI, and determine a cut-off value associated with abnormal auditory brainstem response (ABR) early in life.

Design/Subjects

This study enrolled 19 infants with CCMVI and 21 non-infected newborn infants as a control group. Infants with CCMVI were divided into two subgroups according to ABR at the time of initial examination: normal ABR (11 infants) or abnormal ABR (8 infants). Ventricle size was assessed by calculating Evans’ index (EI) and lateral ventricle width/hemispheric width (LVW/HW) ratio on brain CT images, and was compared among groups. A cut-off ventricle size associated with abnormal ABR was determined.

Results

EI and LVW/HW ratio were significantly higher in the CCMVI with abnormal ABR group than the control and CCMVI with normal ABR groups. Cut-off values of 0.26 for EI and 0.28 for LVW/HW ratio had a sensitivity of 100% and 100%, respectively, and a specificity of 73% and 91%, respectively, for association with abnormal ABR.

Conclusions

We established a method for quantitative evaluation of ventricle size using EI and LVW/HW ratio on brain CT images in infants with CCMVI. LVW/HW ratio had a more association with abnormal ABR in the early postnatal period than EI.     

Serotonin-1A receptor stimulation mediates effects of a metabotropic glutamate 2/3 receptor antagonist, 2S-2-amino-2-(1S,2S-2-carboxycycloprop-1-yl)-3-(xanth-9-yl)propanoic acid (LY341495), and an N-methyl-D-aspartate receptor antagonist,ketamine, in the novelty-suppressed feeding test

Rationale

α-Amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) receptor stimulation has been proposed to be a common neural mechanism of metabotropic glutamate 2/3 (mGlu2/3) receptor antagonists and an N-methyl-D-aspartate receptor antagonist, ketamine, exerting antidepressant effects in animal models. AMPA receptor stimulation has also been shown to mediate an increase in the extracellular level of serotonin (5-HT) in the medial prefrontal cortex by an mGlu2/3 receptor antagonist in rats. However, involvement of the serotonergic system in the actions of mGlu2/3 receptor antagonists and ketamine is not well understood.

Objectives

We investigated involvement of the serotonergic system in the effects of an mGlu2/3 receptor antagonist, 2S-2-amino-2-(1S,2S-2-carboxycycloprop-1-yl)-3-(xanth-9-yl)propanoic acid (LY341495), and ketamine in a novelty-suppressed feeding (NSF) test in mice.

Results

The intraperitoneal administration of LY341495 or ketamine at 30 min prior to the test significantly shortened latency to feed, which was attenuated by an AMPA receptor antagonist, 2,3-dioxo-6-nitro-1,2,3,4-tetrahydr­obenzo[f]quinoxaline-7-sulfonamide (NBQX). The effects of LY341495 and ketamine were no longer observed in mice pretreated with a tryptophan hydroxylase inhibitor, para-chlorophenylalanine (PCPA). Moreover, the effects of LY341495 and ketamine were blocked by a 5-HT1A receptor antagonist, N-{2-[4-(2-methoxyphenyl)-1-piperazinyl]ethyl}-N-(2-pyridynyl) cyclohexane-carboxamide (WAY100635), but not by a 5-HT2A/2C receptor antagonist, ritanserin. Likewise, an AMPA receptor potentiator, 2,3-dihydro-1,4-benzodioxin-7-yl-(1-piperidyl)methanone (CX546), shortened latency to feed in the NSF test, which was prevented by depletion of 5-HT and blockade of 5-HT1A receptor.

Conclusions

These results suggest that AMPA receptor-dependent 5-HT release and subsequent 5-HT1A receptor stimulation may be involved in the actions of an mGlu2/3 receptor antagonist and ketamine in the NSF test.