Does mesh implantation affect the spermatic cord structures after inguinal hernia surgery? An experimental study in rats

Background: Inguinal hernia repair is the most common operation in general surgery. Prosthetic reinforcement of the inguinal area with polypropylene mesh has increased dramatically in the last decade. The aim of this study was to evaluate how different types of mesh affect the spermatic cord structures. Methods: Thirty rats were divided into three groups. The spermatic cord was dissected free and a conventional suture repair was performed in group I, an operation mimicking the Lichtenstein operation with a heavyweight polypropylene mesh in group II and the same operation using large pore, lightweighted polypropylene/polyglactin composite mesh in group III. A vasography was performed after 90 days. The cross-sectional area of the vas deferens and s-testosterone from the spermatic vein were measured using the contralateral side as control. Light microscopy of the inguinal canal was performed and inflammation and fibrosis were graded. Results: Vasography revealed patent vas deferens in all animals. In group III, there was a lower s-testosterone in the spermatic vein and a reduced cross-sectional area of the vas deferens on the operated compared to the control side. However, there was no difference in the other groups and there was no significant difference in s-testosterone levels between the groups. There was significantly more inflammation and fibrosis after mesh repair compared to suture repair, but there was no difference between the two mesh groups. Unexpectedly, polyglactin fibres were still seen in specimens in group III after 90 days. Conclusion: In conclusion, the only effect on the spermatic cord structures in a rat model is seen as an impaired s-testosterone production and a reduced cross-sectional area of the vas deferens after use of a low-weight composite mesh compared to the control side. No difference in inflammation or fibrosis was found between heavyweight polypropylene mesh and low-weight composite mesh. Copyright (C) 2004 S. Karger AG, Basel

Randomized clinical trial comparing 5-year recurrence rate after laparoscopic versus Shouldice repair of primary inguinal hernia

Background: The Shouldice technique is the 'gold standard' of open non-mesh hernia repair. The aim of this study was to compare 5-year recurrence rates after Shouldice and laparoscopic transabdominal preperitoneal patch (TAPP) repair for primary inguinal hernia. Method: Men with a primary unilateral inguinal hernia were randomized to either Shouldice or TAPP operation. An independent observer scored the surgeons' performance. Follow-up comprised clinical examination after 1 year, a questionnaire after 2 and 3 years, and a clinical examination after 5 years. Results: Between February 1993 and March 1996, 1183 patients were included. Nine hundred and twenty patients were followed for 5 years, 454 in the TAPP group and 466 in the Shouldice group. Recurrences were evenly distributed between groups throughout the follow-up period. The cumulative recurrence rate after 5 years was 6.6 per cent in the TAPP group and 6.7 per cent in the Shouldice group. Postoperative pain was a risk factor for recurrence after Shouldice operation but not after TAPP repair. There was a correlation between a low surgeon's performance score and recurrence. Conclusion: The 5-year recurrence rate is acceptable, with no difference between TAPP and Shouldice repair. Poor operative performance resulted in a higher recurrence rate. The TAPP operation represents an excellent alternative for primary inguinal hernia repair

A tailored approach for the treatment of indirect inguinal hernia in adults--an old problem revisited.

A patent processus vaginalis peritonei (PPV) presents typically as an indirect hernia with an intact inguinal canal floor during childhood. Little is known however about PPV in adults and its best treatment. A cohort study included all consecutive patients admitted for ambulatory open hernia repair. In patients with a PPV, demographics, hernia characteristics, and outcome were prospectively assessed. Annulorrhaphy was the treatment of choice in patients with an internal inguinal ring diameter of < 30 mm. Between 1998 and 2006, 92 PPVs (two bilateral) were diagnosed in 676 open hernia repairs (incidence of 14%). Eighty nine of the 90 patients were males, the median age was 34 years (range: 17-85). A PPV was right-sided in 67% and partially obliterated in 66%. Forty-one patients had an annulorrhaphy and 51 patients had a tension-free mesh repair. The median operation time was significantly shorter in the annulorrhaphy group (38 vs. 48 min, P <.0001). In a median follow-up period of 56 months (27-128), both groups did not differ concerning recurrence (1/41 vs. 2/51), chronic pain (3/41 vs. 4/51), and hypoesthesia (5/41 vs. 9/51). There was however a clear trend to less neuropathic symptoms in favor of annulorrhaphy (0/41 vs. 5/51, P < 0.066). PPV occurs in 14% of adults undergoing hernia repair. In selected patients, annulorrhaphy takes less time and is associated with equally low recurrence but less potential for neuropathic symptoms

Structure of p300 in complex with acyl-CoA variants

Histone acetylation plays an important role in transcriptional activation. Histones are also modified by chemically diverse acylations that are frequently deposited by p300, a transcriptional coactivator that uses a number of different acyl-CoA cofactors. Here we report that while p300 is a robust acetylase, its activity gets weaker with increasing acyl-CoA chain length. Crystal structures of p300 in complex with propionyl-, crotonyl-, or butyryl-CoA show that the aliphatic portions of these cofactors are bound in the lysine substrate-binding tunnel in a conformation that is incompatible with substrate transfer. Lysine substrate binding is predicted to remodel the acyl-CoA ligands into a conformation compatible with acyl-chain transfer. This remodeling requires that the aliphatic portion of acyl-CoA be accommodated in a hydrophobic pocket in the enzymes active site. The size of the pocket and its aliphatic nature exclude long-chain and charged acyl-CoA variants, presumably explaining the cofactor preference for p300