Tau protein is required for amyloid {beta}-induced impairment of hippocampal long-term potentiation.

Amyloid ß (Aß) and tau protein are both implicated in memory impairment, mild cognitive impairment (MCI), and early Alzheimer's disease (AD), but whether and how they interact is unknown. Consequently, we asked whether tau protein is required for the robust phenomenon of Aß-induced impairment of hippocampal long-term potentiation (LTP), a widely accepted cellular model of memory. We used wild-type mice and mice with a genetic knock-out of tau protein and recorded field potentials in an acute slice preparation. We demonstrate that the absence of tau protein prevents Aß-induced impairment of LTP. Moreover, we show that Aß increases tau phosphorylation and that a specific inhibitor of the tau kinase glycogen synthase kinase 3 blocks the increased tau phosphorylation induced by Aß and prevents Aß-induced impairment of LTP in wild-type mice. Together, these findings show that tau protein is required for Aß to impair synaptic plasticity in the hippocampus and suggest that the Aß-induced impairment of LTP is mediated by tau phosphorylation. We conclude that preventing the interaction between Aß and tau could be a promising strategy for treating cognitive impairment in MCI and early AD.

A 5-year audit of 778 neonatal renal scans (Part 1): perplexing pyelectasis and suggested protocol for investigation.

In this 5-year review of 778 neonatal renal scans seen in an Obstetric Hospital, most infants were referred because of antenatal ultrasound findings, 92% with fetal pyelectasis. The results were classified according to the ultrasound findings. The majority of neonates (76%) had a normal postnatal scan. A number had vesicoureteric reflux (VUR) found on a micturating cystourethrogram. Persistant mild to moderate pyelectasis or hydronephrosis (15%) proved to be a normal variant in many infants, but had a similar appearance to those with an early obstructive cause (1%). Pyelectasis has proved to be a poor predictor of VUR. A protocol outlining paediatric management for neonates with persisting pyelectasis is included. There were 59 infants (8%) with a miscellaneous group of renal anomalies, many with a characteristic antenatal ultrasound appearance suggesting the diagnosis. These infants have been separately reported and illustrated (Part 2). Overall, 13% of infants were found to have significant findings of obstruction, VUR or miscellaneous anomalies affecting management.

A 5-year audit of 778 neonatal renal scans (Part 2). Miscellaneous anomalies in 59 infants: a pictorial presentation.

In this 5-year review of 778 neonatal renal scans seen in an obstetric hospital, Mercy Hospital for Women, Melbourne, most infants were referred because of antenatal ultrasound findings. Ninety-two percent of these had fetal pyelectasis. The results were classified on the ultrasound findings. The majority of neonates (76%) had a normal postnatal scan. A number had vesicoureteric reflux found on micturating cystourethrogram. Persisting mild/moderate pyelectasis or hydronephrosis (15%) proved to be a normal variant in many infants, but had a similar appearance to those with an early obstructive cause (1%). There were 59 infants (8%) with a miscellaneous group of renal anomalies, many with a characteristic antenatal ultrasound appearance suggesting the diagnosis. Review of these 59 infants illustrates the anomalies seen and reports the associated investigations and subsequent outcome in most cases.