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For more than a decade now blue native polyacrylamide gel electrophoresis (BN-PAGE) has been used for the study of the oxidative phosphorylation (OXPHOS) complexes. Catalytic activities of complexes I, II, IV and V can be assessed, after separation by gel electrophoresis, by incubation of the BN-PAGE gel in specific staining solutions. However, until now, a reliable staining method for testing ubiquinol cytochrome c oxidoreductase (complex III) activity by BN-PAGE gel techniques was not available. In addition, spectrophotometric methods currently in use for detection of complex III deficiency in patients are not very sensitive. Here, we describe a newly developed diagnostic method for visualization of complex III activity by direct in-gel evaluation of ubiquinol cytochrome oxidoreductase activity. We validated the method by reporting the results in six patients with previously characterised complex III defects.

We used near-infrared spectroscopy (NIRS) to study responses to speech and music on the auditory cortices of 13 healthy full-term newborn infants during natural sleep. The purpose of the study was to investigate the lateralization of speech and music responses at this stage of development. NIRS data was recorded from eight positions on both hemispheres simultaneously with electroencephalography, electrooculography, electrocardiography, pulse oximetry, and inclinometry. In 11 subjects, statistically significant (P < 0.02) oxygenated (HbO2) and total hemoglobin (HbT) responses were recorded. Both stimulus types elicited significant HbO2 and HbT responses on both hemispheres in five subjects. Six of the 11 subjects had positive HbO2 and HbT responses to both stimulus types, whereas one subject had negative responses. Mixed positive and negative responses were observed in four neonates. On both hemispheres, speech and music responses were significantly correlated (r = 0.64; P = 0.018 on the left hemisphere (LH) and r = 0.60; P = 0.029 on the right hemisphere (RH)). On the group level, the average response to the speech stimuli was statistically significantly greater than zero in the LH, whereas responses on the RH or to the music stimuli did not differ significantly from zero. This suggests a more coherent response to speech on the LH. However, significant differences in lateralization of the responses or mean response amplitudes of the two stimulus types were not observed on the group level., (Copyright 2009 Wiley-Liss, Inc.)

Objective: A prenatal diagnosis of the fetus for a mother of two previously deceased infants who died from the recently described autosomal recessive disease (OMIM 603358). The infants presented with intrauterine growth retardation, aminoaciduria, cholestasis, iron overload, severe lactic acidosis, and early death (GRACILE syndrome)., Study Design: DNA was extracted from the fibroblasts and tissue samples of the deceased infants, parental leukocytes, and from a chorion villus biopsy in the next pregnancy. Haplotypes were determined using the relevant markers flanking the disease-associated region of chromosome 2., Results: Both deceased infants were homozygous for the four critical markers. The fetal haploptypes were identical to those of the siblings and the pregnancy was terminated. The iron content of the fetal liver was increased (5000 microg/g) compared with the controls, with a marked iron accumulation in the Kupffer cells., Conclusions: Antenatal diagnosis can be performed based on linkage analysis in families with at least one affected child because the disease locus has been assigned to a restricted chromosomal region. Typical histological abnormalities may be present in early fetal life.

Objective: We sought to provide a rational basis for morphine administration in preterm infants in the immediate postnatal period by determining the clearance and evaluating the efficacy and adverse effects of a continuous infusion., Study Design: Morphine was infused for 2 to 4 days (140 microg/kg over 1 hour followed by 20 microg/kg/h) to 31 ventilator-treated newborn infants (gestational age, 24 to 41 weeks; birth weight, 765 to 4,015 g). Morphine, morphine-3-glucuronide, and morphine-6-glucuronide concentrations in serum were determined from arterial blood obtained at 2, 12, 24, 48, and 60 hours after the start of morphine infusion at a median postnatal age of 10 hours., Results: The mean +/- SD steady-state morphine concentration, 167 +/- 77 ng/mL, was achieved between 24 and 48 hours of infusion, and morphine-6-glucuronide and morphine-3-glucuronide concentrations did not reach steady state within 60 hours. Morphine clearance (range, 0.8 to 6.5 mL/min/kg) correlated significantly with gestational age (r = 0.60; P < .01) and birth weight (r = 0.55; P < .01). Pain relief did not correlate with the steady-state morphine concentration. However, significantly higher morphine concentrations were found in infants with decreased gastrointestinal motility (187 +/- 82 ng/mL) compared with those without (128 +/- 51 ng/mL; P < .05)., Conclusions: Morphine should be used with caution in prematurely born infants because of its low clearance, which correlates with gestational age.

Hyperprostaglandin E syndrome is a rare disease usually presenting with renal symptoms such as polyuria, polyhydramnios, hypercalciuria, hypokalaemia, and recurrent episodes of extreme fever, diarrhoea, and convulsions. We report a severe variant of this syndrome with obvious pain and prostaglandin E2 (PGE2)-stimulated hyperthyroidism, an association not previously described. Urinary excretion of PGE2 and its metabolite 7 alpha-hydroxy-5,11-diketotetranorprosta-1,16-dioic acid were markedly increased above normal levels (to 53.3 and 1895 ng/h per 1.73 m2, respectively). We studied oxidative capacity of peroxisomes and mitochondria, the sites where PGE2 oxidation takes place. A generalized mitochondrial disease could be ruled out and no deficiency was found in liver peroxisomal oxidases. The basic pathology of hyperprostaglandin E syndrome remains unsolved.