Signals of selection and ancestry in independently feral Gallus gallus populations.

Recent work indicates that feralisation is not a simple reversal of domestication, and therefore raises questions about the predictability of evolution across replicated feral populations. In the present study we compare genes and traits of two independently established feral populations of chickens (Gallus gallus) that inhabit archipelagos within the Pacific and Atlantic regions to test for evolutionary parallelism and/or divergence. We find that feral populations from each region are genetically closer to one another than other domestic breeds, despite their geographical isolation and divergent colonisation histories. Next, we used genome scans to identify genomic regions selected during feralisation (selective sweeps) in two independently feral populations from Bermuda and Hawaii. Three selective sweep regions (each identified by multiple detection methods) were shared between feral populations, and this overlap is inconsistent with a null model in which selection targets are randomly distributed throughout the genome. In the case of the Bermudian population, many of the genes present within the selective sweeps were either not annotated or of unknown function. Of the nine genes that were identifiable, five were related to behaviour, with the remaining genes involved in bone metabolism, eye development and the immune system. Our findings suggest that a subset of feralisation loci (i.e. genomic targets of recent selection in feral populations) are shared across independently established populations, raising the possibility that feralisation involves some degree of parallelism or convergence and the potential for a shared feralisation 'syndrome'.

Measurements in wound healing with observations on the effects of topical agents on full thickness dermal incised wounds.

INTRODUCTION: A multitude of topical wound treatments are used today. Although it is well established that the micro-environment of healing wounds can be altered to improve healing, it is difficult to measure the subtle differences in outcome where therapies are compared. METHOD: We compared wound healing properties between four different topical agents in surgically incised wounds in a pig model. The four topical agents, 5% Povidone-Iodine cream, 1% Silver-Sulphadiazine, 2% Mupirocin, and 1% Silver-Sulphadiazine plus 1mg/100g recombinant-human epithelial growth factor (EGF) were randomly assigned to four test animals each. Test agents were compared to each other and to untreated controls. We investigated existing and new methodologies of measurement of wound healing: clinical and histological visual scoring systems, immuno-histochemistry, and computerized image analysis of the wounds on days 3, 7, and 28. RESULTS: All agents were found to have improved healing rates with better cellular architecture. Healing was faster, histological appearance resembled normal architecture sooner, clinical appearance improved, mitotic activity was stimulated and more collagen was deposited in comparison to the wounds with no agents. EGF-treated wounds showed an increased rate of epithelisation, but the rate of healing did not correlate well with evaluation of cosmetic outcome. CONCLUSION: Topical agents improve all aspects of wound healing. The addition of a human recombinant EGF to Silver-Sulphadiazine increases epithelial growth and amounts of collagen in the regenerating wounds at day 7.

Outcome of laparoscopic inguinal hernia repair in a South African private practice setting.

OBJECTIVE: The aim of this study was to determine the recurrence and complication rates of laparoscopic inguinal hernia repair performed in a private practice in Cape Town. DESIGN AND SUBJECTS: An unselected cohort of 507 patients who underwent laparoscopic totally extraperitoneal (TEP) inguinal hernia repair before September 2005 were included in this study, thus ensuring a minimum 5-year follow-up. Patient demographic data, clinical notes, operating notes and outpatient follow-up notes were studied. Patients were interviewed telephonically regarding hernia recurrence, chronic pain and technique preference if they had previously undergone an open repair. All data collected were recorded on an electronic spreadsheet. The primary outcome parameter was recurrence. The secondary outcome parameters were postoperative and long-term complications. RESULTS: Of the 507 patients, 267 were contactable telephonically. There were 384 hernia repairs with a mean follow-up of 8.8 years. There were 9 recurrences (2.3%). The overall complication rate was 7.9%. Two per cent of patients suffered from chronic groin pain with gradual improvement since surgery. Sixteen per cent of patients had had previous open repair of an inguinal hernia, either on the ipsilateral or the contralateral side, and all judged the open repair to have been more painful. CONCLUSIONS: The recurrence and complication rates for laparoscopic TEP inguinal hernia repair in this practice are low and comparable to the best reported series. There is a low incidence of persistent postoperative pain with the laparoscopic technique, and it is the technique preferred by patients who previously underwent an open repair.

Factors that influence volume and duration of wound drainage after mastectomy and level III axillary node clearance.

Factors influencing drainage after operations for breast cancer remain controversial. The total volume and duration of drainage was prospectively measured in 252 women undergoing mastectomy and level III axillary clearance, and compared to patient, operative and tumour factors, using multivariate analysis. The total drainage and duration, respectively, correlated with the weight of the patient (r=0.39, P<0.01; r=0.29, P<0.01) and breast weight (r=0.37, P<0.01; r=0.29, P<0.01), and was predicted by the volume on the first postoperative day (r=0.58, P<0.01; r=0.50, P<0.01). There was no correlation with age, blood loss, length of operation, tumour size, number of axillary nodes retrieved, or whether nodes were involved by cancer. The volume and duration of drainage appear thus to be simply a function of the area of tissue planes opened.

The relationship between sigmoidal intramucosal pH and intestinal arterial occlusion during aortic reconstructive surgery.

OBJECTIVES: To investigate the effects of perioperative occlusion of intestinal arteries on clinical outcome and changes in sigmoidal intramuscular pH (pHi). To determine the value of sigmoidal pHi measurement in predicting ischaemic colitis after aortic reconstructive surgery. DESIGN: Prospective, non-selective, open study. MATERIALS: Forty patients undergoing elective aortic infrarenal surgery were monitored with pHi. Pre- and postoperative digital venous subtraction angiography was combined with operative data to evaluate perioperative occlusion of intestinal arteries. RESULTS: All patients had a significant (p< 0.05) drop in pHi after aortic clamping which returned to baseline 2-4 h after declamping. None of the patients had clinical signs of ischaemic colitis postoperatively. All patients had angiographically proven, patent superior mesenteric arteries pre- and postoperatively. Patients were divided into three groups: patients with no changes in intestinal arteries (n=13), patients with perioperative occlusion of the inferior mesenteric artery (n=22) and patients with perioperative occlusion of the inferior mesenteric and one or both iliac arteries (n = 5); there were no significant differences in pHi values between the groups. CONCLUSIONS: Return of the sigmoidal pHi to baseline values within 6-12 h after declamping probably predicts a postoperative course without ischaemic colitis. Perioperative occlusion of the inferior mesenteric artery alone, or in combination with occlusion of one or both internal iliac arteries, does not cause ischaemic colitis in patients whose sigmoidal pHi rises after declamping.

Prone position for ventilation in patients with severe adult respiratory distress syndrome.

We report 3 cases of severe adult respiratory distress syndrome. The patients were very difficult to oxygenate, even with the most advanced conventional mechanical ventilation techniques. In all cases oxygenation improved dramatically when the patient was turned to the prone position. Reports of the use of the prone position for ventilation are scanty, and this is the first time it has been reported in this country. The proposed mechanisms for its effectiveness are reviewed.