Superiority trial for the development of an ideal method for the closure of midline abdominal wall incisions to reduce the incidence of wound complications after elective gastroenterological surgery: study protocol for a randomized controlled trial.

BACKGROUND: The recent guidelines from the European and American Hernia Societies recommend a continuous small-bite suturing technique with slowly absorbable sutures for fascial closure of midline abdominal wall incisions to reduce the incidence of wound complications, especially for incisional hernia. However, this is based on low-certainty evidence. We could not find any recommendations for skin closure. The wound closure technique is an important determinant of the risk of wound complications, and a comprehensive approach to prevent wound complications should be developed. METHODS: We propose a single-institute, prospective, randomized, blinded-endpoint trial to assess the superiority of the combination of continuous suturing of the fascia without peritoneal closure and continuous suturing of the subcuticular tissue (study group) over that of interrupted suturing of the fascia together with the peritoneum and interrupted suturing of the subcuticular tissue (control group) for reducing the incidence of midline abdominal wall incision wound complications after elective gastroenterological surgery with a clean-contaminated wound. Permuted-block randomization with an allocation ratio of 1:1 and blocking will be used. We hypothesize that the study group will show a 50% reduction in the incidence of wound complications. The target number of cases is set at 284. The primary outcome is the incidence of wound complications, including incisional surgical site infection, hemorrhage, seroma, wound dehiscence within 30 days after surgery, and incisional hernia at approximately 1 year after surgery. DISCUSSION: This trial will provide initial evidence on the ideal combination of fascial and skin closure for midline abdominal wall incision to reduce the incidence of overall postoperative wound complications after gastroenterological surgery with a clean-contaminated wound. This trial is expected to generate high-quality evidence that supports the current guidelines for the closure of abdominal wall incisions from the European and American Hernia Societies and to contribute to their next updates. TRIAL REGISTRATION: UMIN-CTR UMIN000048442. Registered on 1 August 2022. https://center6.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000055205.

Gene expression profiles in Ciona intestinalis cleavage-stage embryos.

A total of 1612 expression sequence tags derived from Ciona intestinalis cleavage-stage embryos were examined to explore detailed gene expression profiles. The 3' sequences indicate that the 1612 clones can be categorized into 1066 independent clusters. DDBJ database search suggested that 496 of them showed significant matches to reported proteins with distinct functions. Among them 69 are associated with cell-cell communications and 41 with transcription factors. In situ hybridization of all 1066 clusters showed that 84 clusters exhibited blastomere-specific pattern of expression, and many of these genes seem to encode for novel proteins. One of the interesting findings is that most of them were expressed in the precursor cells of multiple tissues. Among them 28 genes were expressed in the marginal zone of the 32-cell embryo. The blastomeres in this region are thought to receive an inductive signal from the vegetal blastomeres. Many of the blastomere-specific genes did not show similarity to known proteins. The present analysis therefore provides new information for further analyses on the cell fate specification in the Ciona embryo.