Drosophila eggshell production: identification of new genes and coordination by Pxt.

Drosophila ovarian follicles complete development using a spatially and temporally controlled maturation process in which they resume meiosis and secrete a multi-layered, protective eggshell before undergoing arrest and/or ovulation. Microarray analysis revealed more than 150 genes that are expressed in a stage-specific manner during the last 24 hours of follicle development. These include all 30 previously known eggshell genes, as well as 19 new candidate chorion genes and 100 other genes likely to participate in maturation. Mutations in pxt, encoding a putative Drosophila cyclooxygenase, cause many transcripts to begin expression prematurely, and are associated with eggshell defects. Somatic activity of Pxt is required, as RNAi knockdown of pxt in the follicle cells recapitulates both the temporal expression and eggshell defects. One of the temporally regulated genes, cyp18a1, which encodes a cytochromome P450 protein mediating ecdysone turnover, is downregulated in pxt mutant follicles, and cyp18a1 mutation itself alters eggshell gene expression. These studies further define the molecular program of Drosophila follicle maturation and support the idea that it is coordinated by lipid and steroid hormonal signals.

The expression profile of purified Drosophila germline stem cells.

We developed a method to highly purify germline stem cells (GSCs) from the Drosophila ovary, one of the best understood types of adult stem cell. GSCs express variant isoforms of general transcriptional components, translation initiation factors, and several variant ribosomal proteins, including RpL22, a protein enriched in several mammalian stem cells. These novel isoforms may help regulate stem cell gene expression because a reversion assay indicated that at least four were specific for GSCs. By comparative analysis, we identify additional genes enriched in GSCs, including Psc, the Drosophila homolog of the Bmi-1 Polycomb group gene, as well as genes that may delay cytokinesis in pre-meiotic germ cells. By comparing GSCs arrested by BMP over-expression and bam mutation, we hypothesize that mRNA utilization is modulated in differentiating GSC daughters. Our findings suggest that Drosophila and mammalian stem cells utilize at least two regulatory mechanisms in common.

An exploration of outcome criteria in nocturnal enuresis treatment.

This paper is a review of outcome definitions and criteria for nocturnal enuresis treatment. A search of the literature published between 1991 and 2001 highlighted 97 papers. Although the International Children's Continence Society and the World Health Organization have published outcome criteria, different, often idiosyncratic, outcome criteria and/or definitions have been adopted in published research on treatment for nocturnal enuresis in recent years. There remains a debate as to what constitutes successful treatment and how to document improvement. Lack of an agreed definition of outcome reduces confidence in comparing studies, with serious clinical and research implications. This paper reviews aspects of importance in determining outcome, including a suggestion to focus on the establishment of dry nights rather than the reduction of wet nights. A new set of criteria is suggested, consisting of a banding system referred to as a "dryness scale", which focuses on the percentage of dry nights accomplished at a point in time, thus eliminating the need to compare current levels of dryness with a baseline.

Self-construing in children with primary mono-symptomatic nocturnal enuresis--an investigation of three measures.

OBJECTIVE: This study aims to measure different aspects of self-construing in children with primary mono-symptomatic nocturnal enuresis. METHOD: 25 children aged 7-14 years, with nocturnal enuresis were recruited from a paediatric outpatient's unit specialising in enuresis [mean age 10.6 [males], 9.39 [females]] and 25 children acting as controls, were recruited from one primary and one secondary school [mean age 10.08 [males], 9.39 [females]]. MEASURES: The Butler Self Image Profile [SIP], Coopersmith Self Esteem Inventory, Ouvinen-Birgerstam "I think I am" Self Perception Scale were administered. DESIGN: This study was a matched controlled group comparison. RESULTS: The only significant difference was the tendency for children with enuresis to construe themselves more negatively on the SIP. There were no significant differences between children with enuresis and the matched controls on all the other measures. CONCLUSION: Children with nocturnal enuresis generally perceive themselves similar to children without nocturnal enuresis, and are not "psychologically or emotionally disturbed." It is important to assess a child's self-construing in order to identify those children who are more vulnerable to a lower self-esteem. Future research needs to take into account self-construing in different clinical populations, i.e. those children who have non-mono symptomatic nocturnal enuresis.