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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ydbio.2006.05.005 Byline: Caroline Pope, Judy R. McNeilly, Shiona Coutts, Mike Millar, Richard A. Anderson, Alan S. McNeilly Keywords: Developmental changes; Hormonal identity; Human fetal pituitary; Mouse embryonic pituitary; Gonadotrope lineage; Thyrotrope lineage; [alpha]-GSU regulation Abstract: Genes and orthologous intrinsic and extrinsic factors critical for embryonic pituitary gonadotrope and thyrotrope cell differentiation have been identified mainly in rodents, but data on the human are very limited. In human fetal pituitaries examined between 14 and 19 weeks of gestation using immunofluorescent confocal microscopy, we found that most fetal gonadotropes expressed [alpha]-GSU, LH[beta], and FSH[beta] gonadotropin subunits while almost no cells expressed [alpha]-GSU and LH[beta] alone. Gonadotropes expressing [alpha]-GSU and FSH[beta] only were detected in both male and female pituitaries, increasing in proportion to total gonadotropes in both males and females from 14 (approximately 4.5%) to 19 weeks (approximately 16.5%) with a peak in males of 45.5% compared with females of 16.5% at 17 weeks of gestation. When FSH[beta] or LH[beta] genes were expressed, gonadotropes were non-dividing. This profile of human fetal gonadotrope development differs from the current mouse model. Furthermore, while expression of [alpha]-GSU appears to be the lead protein in gonadotropes, in thyrotropes which ultimately express [alpha]-GSU with TSH[beta], we observed that most if not all thyrotropes were TSH[beta]-positive but [alpha]-GSU-negative until around 19 weeks in human, and e15 in mouse, fetal pituitaries. Furthermore, the TSH[beta]-only thyrotropes were dividing, and TSH[beta] rather than [alpha]-GSU was the lead protein in thyrotrope development. Thus, while biologically active dimeric FSH and LH can be produced by the human fetal pituitary by 14 weeks, dimeric biologically active TSH will only be produced from around 17 weeks of gestation. The mechanism(s) responsible for the different molecular regulation of [alpha]-GSU gene expression in gonadotropes and thyrotropes in the developing human fetal pituitary now requires investigation. Author Affiliation: Medical Research Council Human Reproductive Sciences Unit, Centre for Reproductive Biology, The Queen's Medical Research Institute, 47 Little France Crescent, Edinburgh, EH16 4TJ, UK Article History: Received 7 December 2005; Revised 11 April 2006; Accepted 5 May 2006

Background: Surgical site infections (SSIs) are common, occurring in up to 25% of > 4 million operations performed in England each year. Previous trials of the effect of wound dressings on the risk of developing a SSI are of poor quality and underpowered., Methods/design: This study is a feasibility and pilot trial to examine the feasibility of a full trial that will compare simple dressings, no dressing and tissue-glue as a dressing. It is examining the overall acceptability of trial participation, identifying opportunities for refinement, testing the feasibility of and validating new outcome tools to assess SSI, wound management issues and patients' wound symptom experiences. It is also exploring methods for avoiding performance bias and blinding outcome assessors by testing the feasibility of collecting wound photographs taken in theatre immediately after wound closure and, at 4-8 weeks after surgery, taken by participants themselves or their carers. Finally, it is identifying the main cost drivers for an economic evaluation of dressing types. Integrated qualitative research is exploring acceptability and reasons for non-adherence to allocation. Adults undergoing primary elective or unplanned abdominal general surgery or Caesarean section are eligible. The main exclusion criteria are abdominal or other major surgery less than three months before the index operation or contraindication to dressing allocation. The trial is scheduled to recruit for nine months. The findings will be used to inform the design of a main trial., Discussion: This pilot trial is the first pragmatic study to randomise participants to no dressing or tissue-glue as a dressing versus a simple dressing. Early evidence from the ongoing pilot shows that recruitment is proceeding well and that the interventions are acceptable to participants. Combined with the qualitative findings, the findings will inform whether a main, large trial is feasible and, if so, how it should be designed., Trial Registration: ISRCTN49328913 . Registered on 20 October 2015.

G protein-coupled receptor regulation of gene transcription primarily occurs through the phosphorylation of transcription factors by MAPKs. This requires transduction of an activating signal via scaffold proteins that can ultimately determine the outcome by binding signaling kinases and adapter proteins with effects on the target transcription factor and locus of activation. By investigating these mechanisms, we have elucidated how pituitary gonadotrope cells decode an input GnRH signal into coherent transcriptional output from the LH beta-subunit gene promoter. We show that GnRH activates c-Src and multiple members of the MAPK family, c-Jun NH2-terminal kinase 1/2, p38MAPK, and ERK1/2. Using dominant-negative point mutations and chemical inhibitors, we identified that calcium-dependent proline-rich tyrosine kinase 2 specifically acts as a scaffold for a focal adhesion/cytoskeleton-dependent complex comprised of c-Src, Grb2, and mSos that translocates an ERK-activating signal to the nucleus. The locus of action of ERK was specifically mapped to early growth response-1 (Egr-1) DNA binding sites within the LH beta-subunit gene proximal promoter, which was also activated by p38MAPK, but not c-Jun NH2-terminal kinase 1/2. Egr-1 was confirmed as the transcription factor target of ERK and p38MAPK by blockade of protein expression, transcriptional activity, and DNA binding. We have identified a novel GnRH-activated proline-rich tyrosine kinase 2-dependent ERK-mediated signal transduction pathway that specifically regulates Egr-1 activation of the LH beta-subunit proximal gene promoter, and thus provide insight into the molecular mechanisms required for differential regulation of gonadotropin gene expression.