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Purpose: Unpredictable genetic modifications and chromosomal aberrations following CRISPR/Cas9 administration hamper the efficacy of germline editing. Repair events triggered by double-strand DNA breaks (DSBs) besides non-homologous end joining and repair template-driven homology-directed repair have been insufficiently investigated in mouse. In this work, we are the first to investigate the precise repair mechanisms triggered by parental-specific DSB induction in mouse for paternal mutational correction in the context of an infertility-related mutation. Methods: We aimed to correct a paternal 22-nucleotide deletion in Plcz1, associated with lack of fertilisation in vitro, by administrating CRISPR/Cas9 components during intracytoplasmic injection of Plcz1-null sperm in wild-type oocytes combined with assisted oocyte activation. Through targeted next-generation sequencing, 77 injected embryos and 26 blastomeres from seven injected embryos were investigated. In addition, low-pass whole genome sequencing was successfully performed on 17 injected embryo samples. Results: Repair mechanisms induced by two different CRISPR/Cas9 guide RNA (gRNA) designs were investigated. In 13.73% (7/51; gRNA 1) and 19.05% (4/21; gRNA 2) of the targeted embryos, only the wild-type allele was observed, of which the majority (85.71%; 6/7) showed integrity of the targeted chromosome. Remarkably, for both designs, only in one of these embryos (1/7; gRNA 1 and 1/4; gRNA2) could repair template use be detected. This suggests that alternative repair events have occurred. Next, various genetic events within the same embryo were detected after single-cell analysis of four embryos. Conclusion: Our results suggest the occurrence of mosaicism and complex repair events after CRISPR/Cas9 DSB induction where chromosomal integrity is predominantly contained. [ABSTRACT FROM AUTHOR]

Perineal hernias are infrequent complications following abdominoperineal surgeries. These hernias require surgical repair when they become symptomatic by several conventional or reconstructive techniques. The benefits of a full laparoscopic approach and/or the combined approach of a perineal repair of the pelvic floor associated to the laparoscopic placement of a traditional synthetic mesh have been previously demonstrated. In this article, we present the case of a perineal incisional hernia, post-abdominoperineal resection of the rectum after radio chemotherapy, in the neoadjuvant treatment of a rectal adenocarcinoma tumor. An alternative approach, not previously described for the surgical repair of this type of hernia, is presented to assess the feasibility of the suturing repair, and efficacy of a biological acellular porcine collagen implant Permacol(®). A full laparoscopic suturing for the closure of the perineal defect associated to biological mesh reinforcement was successfully undertaken, with good short-term outcomes. [ABSTRACT FROM AUTHOR]

The article describes the case of a 41-year-old male who experienced torsion and infarction of the divided greater omentum 12 months after undergoing laparoscopic Roux-en-Y gastric bypass. The patient complained of severe epigastric and right hypochondric abdominal pain. Clinical examination on the patient revealed epigastric tenderness. The ischemic omentum was removed through an ultrasonic resection.