An evaluation of systematic and random errors in ultrasound estimated fetal weight during serial ultrasound.

Introduction: Ultrasound estimated fetal weight is increasingly being used in the monitoring of fetal growth. Large systematic and random errors in estimated fetal weight have been reported; these may have an impact on the accuracy of fetal growth monitoring. The aim of this study was to attempt to evaluate these systematic and random errors by analysis of serial ultrasound data.

Caveats in the monitoring of fetal growth using ultrasound estimated fetal weight.

Introduction: Ultrasound estimated fetal weight is increasingly being used in the monitoring of fetal growth. Differences between estimated fetal weight formulae, curves and measurement methods could lead to significant differences in results. The aim of this study was to investigate the potential impact of these differences on estimated fetal weight and its use in monitoring fetal growth, both by modelling and by analysis of ultrasound scan data.

Activation of the ALT pathway for telomere maintenance can affect other sequences in the human genome.

Immortal human cells maintain telomere length by the expression of telomerase or through the alternative lengthening of telomeres (ALT). The ALT mechanism involves a recombination-like process that allows the rapid elongation of shortened telomeres. However, it is not known whether activation of the ALT pathway affects other sequences in the genome.

Molecular characterization of inter-telomere and intra-telomere mutations in human ALT cells.

Telomeres in most immortal cells are maintained by the enzyme telomerase, allowing cells to divide indefinitely. Some telomerase-negative tumors and immortal cell lines maintain long heterogeneous telomeres by the ALT (alternative lengthening of telomeres) mechanism; such tumors are expected to be resistant to anti-telomerase drug therapies. Occasionally telomerase-negative Saccharomyces cerevisiae mutants survive, and 10% of them (type II survivors) have unstable telomeres.