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Objectives-To carry out a pilot study to test the feasibility of health visitors (HVs) performing neonatal otoacoustic emissions (OAE) hearing screening in the community using Echoport ILO288 and to evaluate its acceptability to parents and HVs. Design-Prospective cohort study. Setting-Local health centres and babies' homes in urban and rural settings in West Gloucestershire. Participants-Twelve HVs, 683 babies, and their parents. Main outcome measures-Coverage rate, age at testing, referral rate for formal audiology testing, and parental anxiety scores. Results-Of the 683 babies registered with the study HVs, 99% (675) were tested, with a median age at first test of 18 days. Parental consent for the study was refused for six of the eight not tested. Taking a unilateral pass as a screening pass (for comparison with other studies), 4% (27/ 675) failed the first OAE test, and 1.9% (13/675) failed a second OAE test performed by the HV within a further two weeks and were referred for formal audiology testing. One baby (0.15%) was found to have a moderate sensorineural hearing loss on brain stem auditory evoked responses, giving a false positive rate of 1.7% (12/675). Some 18% (120/675) were tested at home, of which 80% (96/120) were combined with another planned reason for HV contact. In all, 82% (555/675) of tests were carried out in health centre clinics, of which 47% (260/555) were combined purpose visits. Mean parental anxiety scores (possible range 0-5) were 0.86, 2.27, and 3.45 before the first test, first retest, and audiology test respectively. The median time taken for one HV to complete testing was 12.2 minutes (range 3-65), compared with the 15 minutes currently allocated for two HVs to perform distraction testing. Based on the results of questionnaires, the test was very well received by parents and HVs alike. Conclusion-HVs are able to perform OAE testing in the neonatal period at home and in local health centre clinics. They achieve high population coverage rates and low false positive rates. Universal neonatal hearing screening by HVs using OAE testing is feasible, well received, and could be less demanding of HV time than the current distraction testing. This model of universal neonatal hearing screening should be considered by the National Screening Committee. (Arch Dis Child Fetal Neonatal Ed 2001;84:F157-F162)

Liver biopsies were collected from control subjects and patients with iron overload due to either primary or secondary haemochromatosis. They were analysed for iron proteins by cation exchange chromatography and flameless atomic absorption spectrophotometry. In control tissue the transferrin fraction contains 25%, ferritin 50% and haemprotein and haemosiderin 10--15% each, of the total iron. In iron overloaded tissue the ferritin and haemosiderin iron increases approximately 10- and 100-fold, respectively, compared with control tissue. There was a close positive correlation between enhanced lysosomal fragility as determined by measurements of latent N-acetyl-beta-glucosaminidase and haemosiderin content of the tissue; it is suggested that the haemosiderin is responsible for the lysosomal disruption and hence the tissue damage in iron overload. Studies were performed on the intracellular localization of ferritin and of total iron in biopsy extracts from control subjects and from patients with iron overload. In control tissue, ferritin contains most of the iron and is apparently free in the cytosol. In iron overload, ferritin is the major iron protein in the post-nuclear supernatant sedimenting into the gradient as the free protein. There are, however, significant amounts of immunoreactive ferritin deeper in the gradients but this cannot be assigned to any particular subcellular organelle. The extreme fragility of lysosomes in iron overloaded human tissue makes isolation of these organelles for detailed biochemical analysis extremely difficult.

Preterm delivery is associated with neurodevelopmental impairment caused by environmental and genetic factors. Dysfunction of the excitatory amino acid transporter 2 (EAAT2) and the resultant impaired glutamate uptake can lead to neurological disorders. In this study, we investigated the role of single nucleotide polymorphisms (SNPs; g.-200C>A and g.-181A>C) in the EAAT2 promoter in susceptibility to brain injury and neurodisability in very preterm infants born at or before 32-week gestation. DNA isolated from newborns’ dried blood spots were used for pyrosequencing to detect both SNPs. Association between EAAT2 genotypes and cerebral palsy, cystic periventricular leukomalacia and a low developmental score was then assessed. The two SNPs were concordant in 89.4% of infants resulting in three common genotypes all carrying two C and two A alleles in different combinations. However, in 10.6% of cases, non-concordance was found, generating six additional rare genotypes. The A alleles at both loci appeared to be detrimental and consequently, the risk of developing cerebral palsy increased four- and sixfold for each additional detrimental allele at -200 and -181 bp, respectively. The two SNPs altered the regulation of the EAAT2 promoter activity and glutamate homeostasis. This study highlights the significance of glutamate in the pathogenesis of preterm brain injury and subsequent development of cerebral palsy and neurodevelopmental disabilities. Furthermore, the described EAAT2 SNPs may be an early biomarker of vulnerability to neurodisability and may aid the development of targeted treatment strategies.Electronic supplementary materialThe online version of this article (doi:10.1007/s12035-017-0462-1) contains supplementary material, which is available to authorized users.