Detection of Novel QTLs for Late Blight Resistance Derived from the Wild Potato Species Solanum microdontum and Solanum pampasense.

Wild potato species continue to be a rich source of genes for resistance to late blight in potato breeding. Whilst many dominant resistance genes from such sources have been characterised and used in breeding, quantitative resistance also offers potential for breeding when the loci underlying the resistance can be identified and tagged using molecular markers. In this study, F1 populations were created from crosses between blight susceptible parents and lines exhibiting strong partial resistance to late blight derived from the South American wild species Solanum microdontum and Solanum pampasense. Both populations exhibited continuous variation for resistance to late blight over multiple field-testing seasons. High density genetic maps were created using single nucleotide polymorphism (SNP) markers, enabling mapping of quantitative trait loci (QTLs) for late blight resistance that were consistently expressed over multiple years in both populations. In the population created with the S. microdontum source, QTLs for resistance consistently expressed over three years and explaining a large portion (21-47%) of the phenotypic variation were found on chromosomes 5 and 6, and a further resistance QTL on chromosome 10, apparently related to foliar development, was discovered in 2016 only. In the population created with the S. pampasense source, QTLs for resistance were found in over two years on chromosomes 11 and 12. For all loci detected consistently across years, the QTLs span known R gene clusters and so they likely represent novel late blight resistance genes. Simple genetic models following the effect of the presence or absence of SNPs associated with consistently effective loci in both populations demonstrated that marker assisted selection (MAS) strategies to introgress and pyramid these loci have potential in resistance breeding strategies.

Surgical correction of tracheo-oesophageal fistula and oesophageal atresia in infants with VACTERL association: a retrospective case-control study.

INTRODUCTION: VACTERL is a rare, non-random association comprising at least three major component features defined by the acronym, and including Vertebral anomalies, Anorectal malformations, Cardiac defects, Tracheo-oEsophageal fistula with or without oesophageal atresia (TOF/OA), Renal abnormalities and Limb anomalies. The aim of this study was to compare the post-operative outcomes following surgical correction of TOF/OA in infants with VACTERL and isolated TOF/OA. METHODS: A retrospective case-control study comparing infants with VACTERL (case group) versus infants with isolated TOF/OA (control group) that underwent surgical correction of TOF/OA at our centre between January 2006 and December 2011. Patient demographics, types of anomalies, operative techniques and post-operative outcomes were collected using inpatient and outpatient records. RESULTS: We identified 30 consecutive infants with TOF/OA. Five infants had VACTERL (17 %) and 15 infants had isolated TOF/OA (50 %). There was no significant difference in the gestational age (P = 0.79), birth weight (P = 0.69) or operative repair (P = 0.14) between groups. Overall, surgical correction of TOF/OA led to satisfactory morbidity. Infants with VACTERL were not at higher risk of post-operative complications, such as oesophageal stricture (P = 0.17) or gastro-oesophageal reflux (P = 1.0), compared to infants with isolated TOF/OA. CONCLUSIONS: VACTERL association does not increase the risk of post-operative complications following TOF/OA repair.

Oesophageal perforation in extreme prematurity.

Management of oesophageal perforation in extremely premature babies is a challenge and carries a high morbidity. The authors report their experience of three separate cases of oesophageal perforation they encountered over the last 18 months in extremely premature neonates. In the first case, the diagnosis of oesophageal perforation was known in an otherwise stable baby who was treated conservatively with a good outcome. In the second and third cases, the patients proceeded to thoracotomy before the diagnosis of a perforated oesophagus was unveiled. A subsequent diagnosis of trisomy 18 and complex cardiac anomalies in the second case proved incompatible with life and treatment was withdrawn. In the final case, an oesophagostomy was fashioned with a gastrostomy for feeding postoperatively and gastric interposition is planned later this year.

Laparoscopic management and outcomes in non-functioning moieties of duplex kidneys in children.

AIMS: Retroperitoneal laparoscopic hemi-nephrectomy (RLHN) is a well tolerated, minimally invasive, although technically demanding, procedure for children with a non-functioning moiety in a duplex kidney. There is very little published data on the long-term follow up of such patients. We collected data to assess outcomes from our experience. METHODS: Data were retrospectively gathered on all patients who underwent RLHN at our institution between February 2003 and July 2008. Follow-up ultrasounds were obtained in all patients. RESULTS: RLHN was performed in 42 patients. All had a non-functioning moiety of a duplex kidney and in addition recurrent urinary tract infections (n=36), incontinence (n=5) or vesico-ureteric reflux (n=1). Median age at surgery was 3 years, 7 months (4 months-13 years, 10 months). One patient required conversion to open procedure due to low (pelvic) kidney. The median operating time was 90min (45-150min). Urine leak developed postoperatively in one patient and loss of function of the remaining moiety occurred in another patient. They were followed up for a median period of 11 months (1-51 months). CONCLUSION: RLHN is a feasible and safe technique for the experienced paediatric laparoscopic urologist. Results compare very favourably with open heminephrectomy in terms of operating time and outcomes. Long-term follow up is mandatory.

Milk curd obstruction in premature infants receiving fortified expressed breast milk.

AIM: Milk curd obstruction is one of the less common causes of neonatal bowel obstruction. It has been described in premature infants who received high caloric formula feeds. We report presentation, management and outcome of premature neonates who developed milk curd obstruction while being fed fortified expressed breast milk. METHODS: A retrospective case note review of babies who were treated for milk curd obstruction in Royal Children's Hospital and Mater Children's Hospital in Brisbane between 2001 and 2007 was performed. RESULTS: Nine preterm neonates developed milk curd obstruction (mean gestational age 27 weeks). All babies received fortified expressed breast milk. Symptoms presented were those of bowel obstruction in the majority of cases. Laparotomy was required in eight babies, one had a pre-existing ileostomy that was washed out. Two babies died shortly after surgery, while two followed several months later. CONCLUSION: The diagnosis of milk curd obstruction should be considered in all premature babies with signs of bowel obstruction who are fed expressed breast milk with caloric fortification.

Foregut atresias and bile duct anomalies: rare, infrequent or common?!

The association of foregut atresias and bile duct anomalies is reportedly rare. We encountered five referrals within 2 years where the secondary diagnosis was missed at operation. Four patients initially presented on antenatal scans as a foregut atresia whereas the fifth presented at nine years with abdominal pain due to a choledochal cyst. The biliary anomalies (cholecysto-hepatic duct, liver cyst and choledochal cysts) in the first four presented as postoperative jaundice during infancy whereas the fifth patient developed subacute intestinal obstruction due to congenital duodenal stenosis at fifteen years. In the patients with duodenal atresia neither did the preoperative X ray reveal any distal bowel gas nor did the subsequent intraoperative cholangiograms reveal bifid common bile duct or pancreato-biliary malunion. Atresias were corrected by primary repair (duodenoduodenostomy for congenital duodenal obstruction in four patients and disconnection/ligation of tracheo-oesophageal fistula with oesophageal anastomosis in one patient). The biliary anomalies were corrected by excision of the abnormal bile ducts (choledochal cyst/liver cyst/cholecystectomy) with Roux en Y hepaticojejunostomy. All patients are asymptomatic and liver function and biliary dilatation has normalised. The association of foregut atresias and bile duct anomalies is not as rare as previously reported. Antenatal ultrasound suggesting either a foregut or a biliary anomaly should alert one to the association. Full radiological and/or imaging investigation may be indicated prior to corrective surgery of the primary anomaly.

Management of infants with Pierre Robin sequence.

OBJECTIVE: Several methods of treating babies with Pierre Robin sequence have been described since the condition itself was first documented in 1923. The main aim of treatment has been to relieve upper airway obstruction. Treatment methods used range from positioning of the baby to invasive surgery. The aim of this article was to describe the assessment, treatment, and monitoring methods used for babies referred with Pierre Robin sequence (PRS). SETTING/PATIENTS: From December 1995 to May 2000, 22 consecutive patients were admitted to Birmingham Children's Hospital with PRS. Their airway and nutritional status were assessed and continuously monitored. INTERVENTIONS: Treatment concentrated on the relief of airway obstruction with a nasopharyngeal airway (NPA) and nutritional support of the babies until they grew out of their respiratory and feeding difficulties. MAIN OUTCOME MEASURES: Outcome measures were oxygen saturation, growth of the babies, and the need for surgery. RESULTS: All babies were managed successfully with an NPA and nutritional support. No baby required surgery, and the majority showed good weight gain. CONCLUSION: Relieving airway obstruction by NPA is an effective and safe treatment for babies with PRS until they have grown out of their respiratory and feeding difficulties. It avoids the need for surgery and can be used on neonatal wards using the monitoring described.