Hormones and Sex-Specific Transcription Factors Jointly Control Yolk Protein Synthesis in Musca domestica

In the housefly Musca domestica, synthesis of yolk proteins (YPs) depends on the level of circulating ecdysteroid hormones. In female houseflies, the ecdysterone concentration in the hemolymph oscillates and, at high levels, is followed by expression of YP. In male houseflies, the ecdysterone titre is constantly low and no YP is produced. In some strains, which are mutant in key components of the sex-determining pathway, males express YP even though their ecdysterone titre is not significantly elevated. However, we find that these males express a substantial amount of the female variant of the Musca doublesex homologue, Md-dsx. The dsx gene is known to sex-specifically control transcription of yp genes in the fat body of Drosophila melanogaster. Our data suggest that Md-dsx also contributes to the regulation of YP expression in the housefly by modulating the responsiveness of YP-producing cells to hormonal stimuli

The transformer2 gene in Musca domestica is required for selecting and maintaining the female pathway of development

We present the isolation and functional analysis of a transformer2 homologue Mdtra2 in the housefly Musca domestica. Compromising the activity of this gene by injecting dsRNA into embryos causes complete sex reversal of genotypically female individuals into fertile males, revealing an essential function of Mdtra2 in female development of the housefly. Mdtra2 is required for female-specific splicing of Musca doublesex (Mddsx) which structurally and functionally corresponds to Drosophila dsx, the bottom-most regulator in the sex-determining pathway. Since Mdtra2 is expressed in males and females, we propose that Mdtra2 serves as an essential co-factor of F, the key sex-determining switch upstream of Mddsx. We also provide evidence that Mdtra2 acts upstream as a positive regulator of F supporting genetic data which suggest that F relies on an autocatalytic activity to select and maintain the female path of development. We further show that repression of male courtship behavior by F requires Mdtra2. This function of F and Mdtra2 appears not to be mediated by Mddsx, suggesting that bifurcation of the pathway at this level is a conserved feature in the genetic architecture of Musca and Drosophil

Sex determination in Drosophila melanogaster and Musca domestica converges at the level of the terminal regulator doublesex

Sex-determining cascades are supposed to have evolved in a retrograde manner from bottom to top. Wilkins' 1995 hypothesis finds support from our comparative studies in Drosophila melanogaster and Musca domestica, two dipteran species that separated some 120million years ago. The sex-determining cascades in these flies differ at the level of the primary sex-determining signal and their targets, Sxl in Drosophila and F in Musca. Here we present evidence that they converge at the level of the terminal regulator, doublesex (dsx), which conveys the selected sexual fate to the differentiation genes. The dsx homologue in Musca, Md-dsx, encodes male-specific (MdDSXM) and female-specific (MdDSXF) protein variants which correspond in structure to those in Drosophila. Sex-specific regulation of Md-dsx is controlled by the switch gene F via a splicing mechanism that is similar but in some relevant aspects different from that in Drosophila. MdDSXF expression can activate the vitellogenin genes in Drosophila and Musca males, and MdDSXM expression in Drosophila females can cause male-like pigmentation of posterior tergites, suggesting that these Musca dsx variants are conserved not only in structure but also in function. Furthermore, downregulation of Md-dsx activity in Musca by injecting dsRNA into embryos leads to intersexual differentiation of the gonads. These results strongly support a role of Md-dsx as the final regulatory gene in the sex-determining hierarchy of the housefl

The length of stay in the post-anaesthesia care unit correlates with pain intensity, nausea and vomiting on arrival

BACKGROUND: The benefit of the post-anaesthesia care unit (PACU) with respect to an early detection of postoperative complications is beyond dispute. From a patient perspective, prevention and optimal management of pain, nausea and vomiting (PONV) are also of utmost importance. The aims of the study were therefore to prospectively measure pain and PONV on arrival to the PACU and before discharge and to determine the relationship of pain and PONV to the length of stay in the PACU. METHODS: Postoperative pain was assessed over 30 months using a numeric rating scale on admittance to the PACU and before discharge; in addition, PONV was recorded. Statistical analysis was done considering gender, age, American Society of Anesthesiologists (ASA) classification, surgical speciality, anaesthesia technique, duration of anaesthesia, intensity of nursing and length of stay. RESULTS: Data of 12,179 patients were available for analysis. The average length of stay in the PACU was 5.7 ± 5.9 h, whereas regular PACU patients stayed for 3.2 ± 1.9 h and more complex IMC patients stayed for 15.1 ± 6.0 h. On admittance, 27% of patients were in pain and the number decreased to 13% before discharge; 3% experienced PONV. Risk factors for increased pain determined by multivariate analysis were female gender; higher ASA classification; general, cardiac and orthopaedic surgery and prolonged case duration. In more complex IMC patients, pain scores were higher on arrival but dropped to similar levels before discharge compared to regular PACU patients. Female gender and postoperative pain were risk factors for postoperative vomiting. Pain and PONV on arrival correlated with length of stay in the PACU. Pain- or PONV-free patients stayed almost half of the time in the PACU compared to patients with severe pain or vomiting on arrival. CONCLUSIONS: The majority of PACU patients had good pain control, both on admittance and before discharge, and the overall incidence of PONV was low. Managing patients in the PACU could achieve a significant reduction of pain and PONV. The level of pain and presence of PONV on admittance to the PACU correlate with and act as predictors for increased length of PACU stay