Atypical Centriolar Composition Correlates with Internal Fertilization in Fish.

The sperm competition theory, as proposed by Geoff Parker, predicts that sperm evolve through a cascade of changes. As an example, internal fertilization is followed by sperm morphology diversification. However, little is known about the evolution of internal sperm structures. The centriole has an ancient and evolutionarily conserved canonical structure with signature 9-fold, radially symmetric microtubules that form the cell's centrosomes, cilia, and flagella. Most animal spermatozoa have two centrioles, one of which forms the spermatozoan flagellum. Both are delivered to the egg and constitute the embryo's first two centrosomes. The spermatozoa of mammals and insects only have one recognizable centriole with a canonical structure. A second sperm centriole with an atypical structure was recently reported in both animal groups and which, prior to this, eluded discovery by standard techniques and criteria. Because the ancestors of both mammals and insects reproduced by internal fertilization, we hypothesized that the transition from two centrioles with canonical composition in ancestral sperm to an atypical centriolar composition characterized by only one canonical centriole evolved preferentially after internal fertilization. We examined fish because of the diversity of species available to test this hypothesis−as some species reproduce via internal and others via external fertilization−and because their spermatozoan ultrastructure has been extensively studied. Our literature search reports on 277 fish species. Species reported with atypical centriolar composition are specifically enriched among internal fertilizers compared to external fertilizers (7/34, 20.6% versus 2/243, 0.80%; p < 0.00001, odds ratio = 32.4) and represent phylogenetically unrelated fish. Atypical centrioles are present in the internal fertilizers of the subfamily Poeciliinae. Therefore, internally fertilizing fish preferentially and independently evolved spermatozoa with atypical centriolar composition multiple times, agreeing with Parker's cascade theory.

ERCP-related perforation: an analysis of operative outcomes in a large series over 12 years.

BACKGROUND: Perforation is a rare but serious adverse event of endoscopic retrograde cholangiopancreatography (ERCP). The aim of this study was to determine the predictors of morbidity and mortality after surgical management of ERCP-related perforation (EP). METHODS: The records of patients with EP requiring surgical intervention at a tertiary referral center in a 12-year period (2004-2016) were retrospectively analyzed for demography, indications for ERCP, risk factors, timing and type of surgical repair, post-operative course, hospital stay, and outcome. Multiple logistic regression was used to identify the parameters predicting survival. RESULTS: Of 25,300 ERCPs, 380 (1.5%) had EP. Non-operative management was successful in 330 (86.8%) patients. 50 (13.2%) patients were operated for EP. Out of 50, the perforation was detected during ERCP (intra-procedure) in 32 patients (64%). In 30 patients (60%), the surgery was performed within 24 h of ERCP. Twenty patients underwent delayed surgery (after 24 h of ERCP) following the failure of initial non-operative management. The delayed surgery after an unsuccessful medical treatment had a detrimental effect on morbidity, mortality and hospital stay. Post-operative duodenal leak was the only independent predictor of 90-day mortality (p = 0.02, OR = 9.1, 95% CI 1.52-54.64). Addition of T-tube duodenostomy (TTD) to the primary repair for either type I or type II perforations increased post-operative duodenal leak (type I, p = 0.048 and type II; p = 0.001) and mortality (type I, p = 0.009 and type II, p = 0.045). CONCLUSION: Although EP is a rare event, it has a serious impact on morbidity and mortality. Delaying of surgery following failed non-operative management worsens the prognosis. Addition of TTD to the repair is not helpful in these patients.

High patency of proximal splenorenal shunt: A myth or reality ? - A prospective cohort study.

BACKGROUND: Proximal splenorenal shunt (PSRS) is a well-accepted surgical procedure for non-cirrhotic portal hypertension (NCPH). Though a patent shunt is important for good long term outcome, there are very few studies on patency of these shunts. We analysed shunt patency using dynamic computed tomographic (CT) portography and compared it with other modalities. METHODS: From 2004 to 2014, 50 patients with PSRS were evaluated prospectively for shunt patency using dynamic CT portography, clinical parameters and ultrasound Doppler. RESULTS: The causes of NCPH were extrahepatic portal vein obstruction (EHPVO) in 38 patients and non-cirrhotic portal fibrosis (NCPF) in 12 patients. The shunt patency rate using clinical parameters, ultrasound Doppler and dynamic CT portography were 70%, 40% and 60% respectively. Clinical parameters overestimated while ultrasound Doppler underestimated the shunt patency rate. Dynamic portography had 100% correlation with conventional angiography in the five patients when this was done. The site of shunt could be demonstrated convincingly by dynamic CT portography. The shunt patency rate decreased over time. It was 64%, 60% and 43% in <1 year, 1-5 years and >5 years respectively. Our NCPF patients had a greater shunt patency rate compared to EHPVO patients (9/12 vs. 21/38) though the difference was not significant. Only size of the splenic vein had a significant impact on the shunt patency rate on statistical analysis. CONCLUSIONS: Dynamic CT portography is useful for evaluation of shunt patency. Proximal splenorenal shunts have a high blockage rate which has hitherto not been reported.

Intrarectal migration of mesh following Rectopexy: Case series and review of literature.

INTRODUCTION: Mesh rectopexy for complete rectal prolapse is associated with complications such as fecal impaction, constipation and rarely recurrence. Mesh erosion following rectopexy is rare. We report three such cases managed successfully in our unit. PRESENTATION OF CASES: All three patients presented with constipation. In addition, one patient had sense of incomplete evacuation and another had protrusion of mesh through anal canal with recurrence of rectal prolapse. There was a delayed presentation in one patient at 15 years after initial surgery, while other two presented at 2 years and 5 years following rectopexy. Diagnosis was made by either per rectal examination or sigmoidoscopy. Two patients underwent trans abdominal removal of mesh along with anterior resection of rectum. In one patient, mesh was removed by transanal approach and sutured rectopexy was added to tackle the recurrent prolapse. All patients are symptom free on follow up with no recurrence of prolapse. DISCUSSION: Mesh erosion following rectopexy has multifactorial aetiology with diverse presentation. It is important to recognise this significantly morbid complication as it amenable to surgical correction. Management depends up on the location of erosion, the severity of mesh protrusion into rectal lumen and the degree of fibrosis around the area of mesh. CONCLUSION: The management of mesh erosion following rectopexy should be individualized. Although it is complex, acceptable functional outcome and quality of life can be achieved with proper treatment.