No abstract

In many organisms, transcription of the zygotic genome begins during the maternal-to-zygotic transition (MZT), which is characterized by a dramatic increase in global transcriptional activities and coincides with embryonic stem cell differentiation. In Drosophila, it has been shown that maternal morphogen gradients and ubiquitously distributed general transcription factors may cooperate to upregulate zygotic genes that are essential for pattern formation in the early embryo. Here, we show that Drosophila STAT (STAT92E) functions as a general transcription factor that, together with the transcription factor Zelda, induces transcription of a large number of early-transcribed zygotic genes during the MZT. STAT92E is present in the early embryo as a maternal product and is active around the MZT. DNA–binding motifs for STAT and Zelda are highly enriched in promoters of early zygotic genes but not in housekeeping genes. Loss of Stat92E in the early embryo, similarly to loss of zelda, preferentially down-regulates early zygotic genes important for pattern formation. We further show that STAT92E and Zelda synergistically regulate transcription. We conclude that STAT92E, in conjunction with Zelda, plays an important role in transcription of the zygotic genome at the onset of embryonic development.

No abstract

To compare the clinical outcome of patients treated with and without platelet-rich plasma (PRP) injection while undergoing arthroscopic labral repair and femoral neck osteoplasty for femoral acetabular impingement. Patients were randomized at the time of surgery to receive either an intra-articular injection of 5 cc of PRP, or an equal volume of 0.9% normal saline. All patients underwent arthroscopic labral repair and osteoplasty of the femoral neck and, at the conclusion of the case, received the injection. One week following surgery, thigh circumference (measured 10 cm distal to the tip of the greater trochanter) and the presence of ecchymosis of the thigh were recorded. Clinical outcome scores, including Non-Arthritic Hip Score, Modified Harris Hip Score and Hip Outcome Score were collected prior to surgery at 1, 3, 6 and a minimum of 12 months post-operatively. Thirty-five patients were enrolled into this study. Twenty patients received a PRP injection and 15 received a saline injection. Thigh circumference was compared pre-operatively and 1 week post-operatively. There was no significant difference between the two groups. Ecchymosis was compared between the two groups at 1 week post-operatively. Four of the 20 patients in the PRP group and 10 of the 15 in the placebo group demonstrated bruising on the lateral thigh. This was compared with a Chi-Square test and found to be statistically significant (P = 0.005). There was no significant difference in any of the outcome scores between the two groups. An intra-articular injection of PRP after labral repair did not improve the clinical outcome up to 1 year post-operatively in patients undergoing arthroscopic labral repair and osteoplasty of the femoral neck. Level of evidence is level I study.